// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2007 Oracle. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "misc.h" #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" #include "ordered-data.h" #include "xattr.h" #include "tree-log.h" #include "bio.h" #include "compression.h" #include "locking.h" #include "props.h" #include "qgroup.h" #include "delalloc-space.h" #include "block-group.h" #include "space-info.h" #include "zoned.h" #include "subpage.h" #include "inode-item.h" #include "fs.h" #include "accessors.h" #include "extent-tree.h" #include "root-tree.h" #include "defrag.h" #include "dir-item.h" #include "file-item.h" #include "uuid-tree.h" #include "ioctl.h" #include "file.h" #include "acl.h" #include "relocation.h" #include "verity.h" #include "super.h" #include "orphan.h" #include "backref.h" #include "raid-stripe-tree.h" #include "fiemap.h" struct btrfs_iget_args { u64 ino; struct btrfs_root *root; }; struct btrfs_rename_ctx { /* Output field. Stores the index number of the old directory entry. */ u64 index; }; /* * Used by data_reloc_print_warning_inode() to pass needed info for filename * resolution and output of error message. */ struct data_reloc_warn { struct btrfs_path path; struct btrfs_fs_info *fs_info; u64 extent_item_size; u64 logical; int mirror_num; }; /* * For the file_extent_tree, we want to hold the inode lock when we lookup and * update the disk_i_size, but lockdep will complain because our io_tree we hold * the tree lock and get the inode lock when setting delalloc. These two things * are unrelated, so make a class for the file_extent_tree so we don't get the * two locking patterns mixed up. */ static struct lock_class_key file_extent_tree_class; static const struct inode_operations btrfs_dir_inode_operations; static const struct inode_operations btrfs_symlink_inode_operations; static const struct inode_operations btrfs_special_inode_operations; static const struct inode_operations btrfs_file_inode_operations; static const struct address_space_operations btrfs_aops; static const struct file_operations btrfs_dir_file_operations; static struct kmem_cache *btrfs_inode_cachep; static int btrfs_setsize(struct inode *inode, struct iattr *attr); static int btrfs_truncate(struct btrfs_inode *inode, bool skip_writeback); static noinline int run_delalloc_cow(struct btrfs_inode *inode, struct folio *locked_folio, u64 start, u64 end, struct writeback_control *wbc, bool pages_dirty); static int data_reloc_print_warning_inode(u64 inum, u64 offset, u64 num_bytes, u64 root, void *warn_ctx) { struct data_reloc_warn *warn = warn_ctx; struct btrfs_fs_info *fs_info = warn->fs_info; struct extent_buffer *eb; struct btrfs_inode_item *inode_item; struct inode_fs_paths *ipath = NULL; struct btrfs_root *local_root; struct btrfs_key key; unsigned int nofs_flag; u32 nlink; int ret; local_root = btrfs_get_fs_root(fs_info, root, true); if (IS_ERR(local_root)) { ret = PTR_ERR(local_root); goto err; } /* This makes the path point to (inum INODE_ITEM ioff). */ key.objectid = inum; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(NULL, local_root, &key, &warn->path, 0, 0); if (ret) { btrfs_put_root(local_root); btrfs_release_path(&warn->path); goto err; } eb = warn->path.nodes[0]; inode_item = btrfs_item_ptr(eb, warn->path.slots[0], struct btrfs_inode_item); nlink = btrfs_inode_nlink(eb, inode_item); btrfs_release_path(&warn->path); nofs_flag = memalloc_nofs_save(); ipath = init_ipath(4096, local_root, &warn->path); memalloc_nofs_restore(nofs_flag); if (IS_ERR(ipath)) { btrfs_put_root(local_root); ret = PTR_ERR(ipath); ipath = NULL; /* * -ENOMEM, not a critical error, just output an generic error * without filename. */ btrfs_warn(fs_info, "checksum error at logical %llu mirror %u root %llu, inode %llu offset %llu", warn->logical, warn->mirror_num, root, inum, offset); return ret; } ret = paths_from_inode(inum, ipath); if (ret < 0) goto err; /* * We deliberately ignore the bit ipath might have been too small to * hold all of the paths here */ for (int i = 0; i < ipath->fspath->elem_cnt; i++) { btrfs_warn(fs_info, "checksum error at logical %llu mirror %u root %llu inode %llu offset %llu length %u links %u (path: %s)", warn->logical, warn->mirror_num, root, inum, offset, fs_info->sectorsize, nlink, (char *)(unsigned long)ipath->fspath->val[i]); } btrfs_put_root(local_root); free_ipath(ipath); return 0; err: btrfs_warn(fs_info, "checksum error at logical %llu mirror %u root %llu inode %llu offset %llu, path resolving failed with ret=%d", warn->logical, warn->mirror_num, root, inum, offset, ret); free_ipath(ipath); return ret; } /* * Do extra user-friendly error output (e.g. lookup all the affected files). * * Return true if we succeeded doing the backref lookup. * Return false if such lookup failed, and has to fallback to the old error message. */ static void print_data_reloc_error(const struct btrfs_inode *inode, u64 file_off, const u8 *csum, const u8 *csum_expected, int mirror_num) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct btrfs_path path = { 0 }; struct btrfs_key found_key = { 0 }; struct extent_buffer *eb; struct btrfs_extent_item *ei; const u32 csum_size = fs_info->csum_size; u64 logical; u64 flags; u32 item_size; int ret; mutex_lock(&fs_info->reloc_mutex); logical = btrfs_get_reloc_bg_bytenr(fs_info); mutex_unlock(&fs_info->reloc_mutex); if (logical == U64_MAX) { btrfs_warn_rl(fs_info, "has data reloc tree but no running relocation"); btrfs_warn_rl(fs_info, "csum failed root %lld ino %llu off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d", btrfs_root_id(inode->root), btrfs_ino(inode), file_off, CSUM_FMT_VALUE(csum_size, csum), CSUM_FMT_VALUE(csum_size, csum_expected), mirror_num); return; } logical += file_off; btrfs_warn_rl(fs_info, "csum failed root %lld ino %llu off %llu logical %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d", btrfs_root_id(inode->root), btrfs_ino(inode), file_off, logical, CSUM_FMT_VALUE(csum_size, csum), CSUM_FMT_VALUE(csum_size, csum_expected), mirror_num); ret = extent_from_logical(fs_info, logical, &path, &found_key, &flags); if (ret < 0) { btrfs_err_rl(fs_info, "failed to lookup extent item for logical %llu: %d", logical, ret); return; } eb = path.nodes[0]; ei = btrfs_item_ptr(eb, path.slots[0], struct btrfs_extent_item); item_size = btrfs_item_size(eb, path.slots[0]); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { unsigned long ptr = 0; u64 ref_root; u8 ref_level; while (true) { ret = tree_backref_for_extent(&ptr, eb, &found_key, ei, item_size, &ref_root, &ref_level); if (ret < 0) { btrfs_warn_rl(fs_info, "failed to resolve tree backref for logical %llu: %d", logical, ret); break; } if (ret > 0) break; btrfs_warn_rl(fs_info, "csum error at logical %llu mirror %u: metadata %s (level %d) in tree %llu", logical, mirror_num, (ref_level ? "node" : "leaf"), ref_level, ref_root); } btrfs_release_path(&path); } else { struct btrfs_backref_walk_ctx ctx = { 0 }; struct data_reloc_warn reloc_warn = { 0 }; btrfs_release_path(&path); ctx.bytenr = found_key.objectid; ctx.extent_item_pos = logical - found_key.objectid; ctx.fs_info = fs_info; reloc_warn.logical = logical; reloc_warn.extent_item_size = found_key.offset; reloc_warn.mirror_num = mirror_num; reloc_warn.fs_info = fs_info; iterate_extent_inodes(&ctx, true, data_reloc_print_warning_inode, &reloc_warn); } } static void __cold btrfs_print_data_csum_error(struct btrfs_inode *inode, u64 logical_start, u8 *csum, u8 *csum_expected, int mirror_num) { struct btrfs_root *root = inode->root; const u32 csum_size = root->fs_info->csum_size; /* For data reloc tree, it's better to do a backref lookup instead. */ if (btrfs_root_id(root) == BTRFS_DATA_RELOC_TREE_OBJECTID) return print_data_reloc_error(inode, logical_start, csum, csum_expected, mirror_num); /* Output without objectid, which is more meaningful */ if (btrfs_root_id(root) >= BTRFS_LAST_FREE_OBJECTID) { btrfs_warn_rl(root->fs_info, "csum failed root %lld ino %lld off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d", btrfs_root_id(root), btrfs_ino(inode), logical_start, CSUM_FMT_VALUE(csum_size, csum), CSUM_FMT_VALUE(csum_size, csum_expected), mirror_num); } else { btrfs_warn_rl(root->fs_info, "csum failed root %llu ino %llu off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d", btrfs_root_id(root), btrfs_ino(inode), logical_start, CSUM_FMT_VALUE(csum_size, csum), CSUM_FMT_VALUE(csum_size, csum_expected), mirror_num); } } /* * Lock inode i_rwsem based on arguments passed. * * ilock_flags can have the following bit set: * * BTRFS_ILOCK_SHARED - acquire a shared lock on the inode * BTRFS_ILOCK_TRY - try to acquire the lock, if fails on first attempt * return -EAGAIN * BTRFS_ILOCK_MMAP - acquire a write lock on the i_mmap_lock */ int btrfs_inode_lock(struct btrfs_inode *inode, unsigned int ilock_flags) { if (ilock_flags & BTRFS_ILOCK_SHARED) { if (ilock_flags & BTRFS_ILOCK_TRY) { if (!inode_trylock_shared(&inode->vfs_inode)) return -EAGAIN; else return 0; } inode_lock_shared(&inode->vfs_inode); } else { if (ilock_flags & BTRFS_ILOCK_TRY) { if (!inode_trylock(&inode->vfs_inode)) return -EAGAIN; else return 0; } inode_lock(&inode->vfs_inode); } if (ilock_flags & BTRFS_ILOCK_MMAP) down_write(&inode->i_mmap_lock); return 0; } /* * Unock inode i_rwsem. * * ilock_flags should contain the same bits set as passed to btrfs_inode_lock() * to decide whether the lock acquired is shared or exclusive. */ void btrfs_inode_unlock(struct btrfs_inode *inode, unsigned int ilock_flags) { if (ilock_flags & BTRFS_ILOCK_MMAP) up_write(&inode->i_mmap_lock); if (ilock_flags & BTRFS_ILOCK_SHARED) inode_unlock_shared(&inode->vfs_inode); else inode_unlock(&inode->vfs_inode); } /* * Cleanup all submitted ordered extents in specified range to handle errors * from the btrfs_run_delalloc_range() callback. * * NOTE: caller must ensure that when an error happens, it can not call * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata * to be released, which we want to happen only when finishing the ordered * extent (btrfs_finish_ordered_io()). */ static inline void btrfs_cleanup_ordered_extents(struct btrfs_inode *inode, struct folio *locked_folio, u64 offset, u64 bytes) { unsigned long index = offset >> PAGE_SHIFT; unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT; u64 page_start = 0, page_end = 0; struct folio *folio; if (locked_folio) { page_start = folio_pos(locked_folio); page_end = page_start + folio_size(locked_folio) - 1; } while (index <= end_index) { /* * For locked page, we will call btrfs_mark_ordered_io_finished * through btrfs_mark_ordered_io_finished() on it * in run_delalloc_range() for the error handling, which will * clear page Ordered and run the ordered extent accounting. * * Here we can't just clear the Ordered bit, or * btrfs_mark_ordered_io_finished() would skip the accounting * for the page range, and the ordered extent will never finish. */ if (locked_folio && index == (page_start >> PAGE_SHIFT)) { index++; continue; } folio = __filemap_get_folio(inode->vfs_inode.i_mapping, index, 0, 0); index++; if (IS_ERR(folio)) continue; /* * Here we just clear all Ordered bits for every page in the * range, then btrfs_mark_ordered_io_finished() will handle * the ordered extent accounting for the range. */ btrfs_folio_clamp_clear_ordered(inode->root->fs_info, folio, offset, bytes); folio_put(folio); } if (locked_folio) { /* The locked page covers the full range, nothing needs to be done */ if (bytes + offset <= page_start + folio_size(locked_folio)) return; /* * In case this page belongs to the delalloc range being * instantiated then skip it, since the first page of a range is * going to be properly cleaned up by the caller of * run_delalloc_range */ if (page_start >= offset && page_end <= (offset + bytes - 1)) { bytes = offset + bytes - folio_pos(locked_folio) - folio_size(locked_folio); offset = folio_pos(locked_folio) + folio_size(locked_folio); } } return btrfs_mark_ordered_io_finished(inode, NULL, offset, bytes, false); } static int btrfs_dirty_inode(struct btrfs_inode *inode); static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, struct btrfs_new_inode_args *args) { int err; if (args->default_acl) { err = __btrfs_set_acl(trans, args->inode, args->default_acl, ACL_TYPE_DEFAULT); if (err) return err; } if (args->acl) { err = __btrfs_set_acl(trans, args->inode, args->acl, ACL_TYPE_ACCESS); if (err) return err; } if (!args->default_acl && !args->acl) cache_no_acl(args->inode); return btrfs_xattr_security_init(trans, args->inode, args->dir, &args->dentry->d_name); } /* * this does all the hard work for inserting an inline extent into * the btree. The caller should have done a btrfs_drop_extents so that * no overlapping inline items exist in the btree */ static int insert_inline_extent(struct btrfs_trans_handle *trans, struct btrfs_path *path, struct btrfs_inode *inode, bool extent_inserted, size_t size, size_t compressed_size, int compress_type, struct folio *compressed_folio, bool update_i_size) { struct btrfs_root *root = inode->root; struct extent_buffer *leaf; const u32 sectorsize = trans->fs_info->sectorsize; char *kaddr; unsigned long ptr; struct btrfs_file_extent_item *ei; int ret; size_t cur_size = size; u64 i_size; /* * The decompressed size must still be no larger than a sector. Under * heavy race, we can have size == 0 passed in, but that shouldn't be a * big deal and we can continue the insertion. */ ASSERT(size <= sectorsize); /* * The compressed size also needs to be no larger than a sector. * That's also why we only need one page as the parameter. */ if (compressed_folio) ASSERT(compressed_size <= sectorsize); else ASSERT(compressed_size == 0); if (compressed_size && compressed_folio) cur_size = compressed_size; if (!extent_inserted) { struct btrfs_key key; size_t datasize; key.objectid = btrfs_ino(inode); key.offset = 0; key.type = BTRFS_EXTENT_DATA_KEY; datasize = btrfs_file_extent_calc_inline_size(cur_size); ret = btrfs_insert_empty_item(trans, root, path, &key, datasize); if (ret) goto fail; } leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, ei, trans->transid); btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); btrfs_set_file_extent_encryption(leaf, ei, 0); btrfs_set_file_extent_other_encoding(leaf, ei, 0); btrfs_set_file_extent_ram_bytes(leaf, ei, size); ptr = btrfs_file_extent_inline_start(ei); if (compress_type != BTRFS_COMPRESS_NONE) { kaddr = kmap_local_folio(compressed_folio, 0); write_extent_buffer(leaf, kaddr, ptr, compressed_size); kunmap_local(kaddr); btrfs_set_file_extent_compression(leaf, ei, compress_type); } else { struct folio *folio; folio = __filemap_get_folio(inode->vfs_inode.i_mapping, 0, 0, 0); ASSERT(!IS_ERR(folio)); btrfs_set_file_extent_compression(leaf, ei, 0); kaddr = kmap_local_folio(folio, 0); write_extent_buffer(leaf, kaddr, ptr, size); kunmap_local(kaddr); folio_put(folio); } btrfs_mark_buffer_dirty(trans, leaf); btrfs_release_path(path); /* * We align size to sectorsize for inline extents just for simplicity * sake. */ ret = btrfs_inode_set_file_extent_range(inode, 0, ALIGN(size, root->fs_info->sectorsize)); if (ret) goto fail; /* * We're an inline extent, so nobody can extend the file past i_size * without locking a page we already have locked. * * We must do any i_size and inode updates before we unlock the pages. * Otherwise we could end up racing with unlink. */ i_size = i_size_read(&inode->vfs_inode); if (update_i_size && size > i_size) { i_size_write(&inode->vfs_inode, size); i_size = size; } inode->disk_i_size = i_size; fail: return ret; } static bool can_cow_file_range_inline(struct btrfs_inode *inode, u64 offset, u64 size, size_t compressed_size) { struct btrfs_fs_info *fs_info = inode->root->fs_info; u64 data_len = (compressed_size ?: size); /* Inline extents must start at offset 0. */ if (offset != 0) return false; /* * Due to the page size limit, for subpage we can only trigger the * writeback for the dirty sectors of page, that means data writeback * is doing more writeback than what we want. * * This is especially unexpected for some call sites like fallocate, * where we only increase i_size after everything is done. * This means we can trigger inline extent even if we didn't want to. * So here we skip inline extent creation completely. */ if (fs_info->sectorsize != PAGE_SIZE) return false; /* Inline extents are limited to sectorsize. */ if (size > fs_info->sectorsize) return false; /* We cannot exceed the maximum inline data size. */ if (data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info)) return false; /* We cannot exceed the user specified max_inline size. */ if (data_len > fs_info->max_inline) return false; /* Inline extents must be the entirety of the file. */ if (size < i_size_read(&inode->vfs_inode)) return false; return true; } /* * conditionally insert an inline extent into the file. This * does the checks required to make sure the data is small enough * to fit as an inline extent. * * If being used directly, you must have already checked we're allowed to cow * the range by getting true from can_cow_file_range_inline(). */ static noinline int __cow_file_range_inline(struct btrfs_inode *inode, u64 offset, u64 size, size_t compressed_size, int compress_type, struct folio *compressed_folio, bool update_i_size) { struct btrfs_drop_extents_args drop_args = { 0 }; struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans; u64 data_len = (compressed_size ?: size); int ret; struct btrfs_path *path; path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } trans->block_rsv = &inode->block_rsv; drop_args.path = path; drop_args.start = 0; drop_args.end = fs_info->sectorsize; drop_args.drop_cache = true; drop_args.replace_extent = true; drop_args.extent_item_size = btrfs_file_extent_calc_inline_size(data_len); ret = btrfs_drop_extents(trans, root, inode, &drop_args); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } ret = insert_inline_extent(trans, path, inode, drop_args.extent_inserted, size, compressed_size, compress_type, compressed_folio, update_i_size); if (ret && ret != -ENOSPC) { btrfs_abort_transaction(trans, ret); goto out; } else if (ret == -ENOSPC) { ret = 1; goto out; } btrfs_update_inode_bytes(inode, size, drop_args.bytes_found); ret = btrfs_update_inode(trans, inode); if (ret && ret != -ENOSPC) { btrfs_abort_transaction(trans, ret); goto out; } else if (ret == -ENOSPC) { ret = 1; goto out; } btrfs_set_inode_full_sync(inode); out: /* * Don't forget to free the reserved space, as for inlined extent * it won't count as data extent, free them directly here. * And at reserve time, it's always aligned to page size, so * just free one page here. */ btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE, NULL); btrfs_free_path(path); btrfs_end_transaction(trans); return ret; } static noinline int cow_file_range_inline(struct btrfs_inode *inode, struct folio *locked_folio, u64 offset, u64 end, size_t compressed_size, int compress_type, struct folio *compressed_folio, bool update_i_size) { struct extent_state *cached = NULL; unsigned long clear_flags = EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING | EXTENT_LOCKED; u64 size = min_t(u64, i_size_read(&inode->vfs_inode), end + 1); int ret; if (!can_cow_file_range_inline(inode, offset, size, compressed_size)) return 1; lock_extent(&inode->io_tree, offset, end, &cached); ret = __cow_file_range_inline(inode, offset, size, compressed_size, compress_type, compressed_folio, update_i_size); if (ret > 0) { unlock_extent(&inode->io_tree, offset, end, &cached); return ret; } /* * In the successful case (ret == 0 here), cow_file_range will return 1. * * Quite a bit further up the callstack in extent_writepage(), ret == 1 * is treated as a short circuited success and does not unlock the folio, * so we must do it here. * * In the failure case, the locked_folio does get unlocked by * btrfs_folio_end_all_writers, which asserts that it is still locked * at that point, so we must *not* unlock it here. * * The other two callsites in compress_file_range do not have a * locked_folio, so they are not relevant to this logic. */ if (ret == 0) locked_folio = NULL; extent_clear_unlock_delalloc(inode, offset, end, locked_folio, &cached, clear_flags, PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK); return ret; } struct async_extent { u64 start; u64 ram_size; u64 compressed_size; struct folio **folios; unsigned long nr_folios; int compress_type; struct list_head list; }; struct async_chunk { struct btrfs_inode *inode; struct folio *locked_folio; u64 start; u64 end; blk_opf_t write_flags; struct list_head extents; struct cgroup_subsys_state *blkcg_css; struct btrfs_work work; struct async_cow *async_cow; }; struct async_cow { atomic_t num_chunks; struct async_chunk chunks[]; }; static noinline int add_async_extent(struct async_chunk *cow, u64 start, u64 ram_size, u64 compressed_size, struct folio **folios, unsigned long nr_folios, int compress_type) { struct async_extent *async_extent; async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); if (!async_extent) return -ENOMEM; async_extent->start = start; async_extent->ram_size = ram_size; async_extent->compressed_size = compressed_size; async_extent->folios = folios; async_extent->nr_folios = nr_folios; async_extent->compress_type = compress_type; list_add_tail(&async_extent->list, &cow->extents); return 0; } /* * Check if the inode needs to be submitted to compression, based on mount * options, defragmentation, properties or heuristics. */ static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, u64 end) { struct btrfs_fs_info *fs_info = inode->root->fs_info; if (!btrfs_inode_can_compress(inode)) { WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), KERN_ERR "BTRFS: unexpected compression for ino %llu\n", btrfs_ino(inode)); return 0; } /* * Only enable sector perfect compression for experimental builds. * * This is a big feature change for subpage cases, and can hit * different corner cases, so only limit this feature for * experimental build for now. * * ETA for moving this out of experimental builds is 6.15. */ if (fs_info->sectorsize < PAGE_SIZE && !IS_ENABLED(CONFIG_BTRFS_EXPERIMENTAL)) { if (!PAGE_ALIGNED(start) || !PAGE_ALIGNED(end + 1)) return 0; } /* force compress */ if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) return 1; /* defrag ioctl */ if (inode->defrag_compress) return 1; /* bad compression ratios */ if (inode->flags & BTRFS_INODE_NOCOMPRESS) return 0; if (btrfs_test_opt(fs_info, COMPRESS) || inode->flags & BTRFS_INODE_COMPRESS || inode->prop_compress) return btrfs_compress_heuristic(inode, start, end); return 0; } static inline void inode_should_defrag(struct btrfs_inode *inode, u64 start, u64 end, u64 num_bytes, u32 small_write) { /* If this is a small write inside eof, kick off a defrag */ if (num_bytes < small_write && (start > 0 || end + 1 < inode->disk_i_size)) btrfs_add_inode_defrag(inode, small_write); } static int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end) { unsigned long end_index = end >> PAGE_SHIFT; struct folio *folio; int ret = 0; for (unsigned long index = start >> PAGE_SHIFT; index <= end_index; index++) { folio = __filemap_get_folio(inode->i_mapping, index, 0, 0); if (IS_ERR(folio)) { if (!ret) ret = PTR_ERR(folio); continue; } btrfs_folio_clamp_clear_dirty(inode_to_fs_info(inode), folio, start, end + 1 - start); folio_put(folio); } return ret; } /* * Work queue call back to started compression on a file and pages. * * This is done inside an ordered work queue, and the compression is spread * across many cpus. The actual IO submission is step two, and the ordered work * queue takes care of making sure that happens in the same order things were * put onto the queue by writepages and friends. * * If this code finds it can't get good compression, it puts an entry onto the * work queue to write the uncompressed bytes. This makes sure that both * compressed inodes and uncompressed inodes are written in the same order that * the flusher thread sent them down. */ static void compress_file_range(struct btrfs_work *work) { struct async_chunk *async_chunk = container_of(work, struct async_chunk, work); struct btrfs_inode *inode = async_chunk->inode; struct btrfs_fs_info *fs_info = inode->root->fs_info; struct address_space *mapping = inode->vfs_inode.i_mapping; u64 blocksize = fs_info->sectorsize; u64 start = async_chunk->start; u64 end = async_chunk->end; u64 actual_end; u64 i_size; int ret = 0; struct folio **folios; unsigned long nr_folios; unsigned long total_compressed = 0; unsigned long total_in = 0; unsigned int poff; int i; int compress_type = fs_info->compress_type; inode_should_defrag(inode, start, end, end - start + 1, SZ_16K); /* * We need to call clear_page_dirty_for_io on each page in the range. * Otherwise applications with the file mmap'd can wander in and change * the page contents while we are compressing them. */ ret = extent_range_clear_dirty_for_io(&inode->vfs_inode, start, end); /* * All the folios should have been locked thus no failure. * * And even if some folios are missing, btrfs_compress_folios() * would handle them correctly, so here just do an ASSERT() check for * early logic errors. */ ASSERT(ret == 0); /* * We need to save i_size before now because it could change in between * us evaluating the size and assigning it. This is because we lock and * unlock the page in truncate and fallocate, and then modify the i_size * later on. * * The barriers are to emulate READ_ONCE, remove that once i_size_read * does that for us. */ barrier(); i_size = i_size_read(&inode->vfs_inode); barrier(); actual_end = min_t(u64, i_size, end + 1); again: folios = NULL; nr_folios = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; nr_folios = min_t(unsigned long, nr_folios, BTRFS_MAX_COMPRESSED_PAGES); /* * we don't want to send crud past the end of i_size through * compression, that's just a waste of CPU time. So, if the * end of the file is before the start of our current * requested range of bytes, we bail out to the uncompressed * cleanup code that can deal with all of this. * * It isn't really the fastest way to fix things, but this is a * very uncommon corner. */ if (actual_end <= start) goto cleanup_and_bail_uncompressed; total_compressed = actual_end - start; /* * Skip compression for a small file range(<=blocksize) that * isn't an inline extent, since it doesn't save disk space at all. */ if (total_compressed <= blocksize && (start > 0 || end + 1 < inode->disk_i_size)) goto cleanup_and_bail_uncompressed; total_compressed = min_t(unsigned long, total_compressed, BTRFS_MAX_UNCOMPRESSED); total_in = 0; ret = 0; /* * We do compression for mount -o compress and when the inode has not * been flagged as NOCOMPRESS. This flag can change at any time if we * discover bad compression ratios. */ if (!inode_need_compress(inode, start, end)) goto cleanup_and_bail_uncompressed; folios = kcalloc(nr_folios, sizeof(struct folio *), GFP_NOFS); if (!folios) { /* * Memory allocation failure is not a fatal error, we can fall * back to uncompressed code. */ goto cleanup_and_bail_uncompressed; } if (inode->defrag_compress) compress_type = inode->defrag_compress; else if (inode->prop_compress) compress_type = inode->prop_compress; /* Compression level is applied here. */ ret = btrfs_compress_folios(compress_type | (fs_info->compress_level << 4), mapping, start, folios, &nr_folios, &total_in, &total_compressed); if (ret) goto mark_incompressible; /* * Zero the tail end of the last page, as we might be sending it down * to disk. */ poff = offset_in_page(total_compressed); if (poff) folio_zero_range(folios[nr_folios - 1], poff, PAGE_SIZE - poff); /* * Try to create an inline extent. * * If we didn't compress the entire range, try to create an uncompressed * inline extent, else a compressed one. * * Check cow_file_range() for why we don't even try to create inline * extent for the subpage case. */ if (total_in < actual_end) ret = cow_file_range_inline(inode, NULL, start, end, 0, BTRFS_COMPRESS_NONE, NULL, false); else ret = cow_file_range_inline(inode, NULL, start, end, total_compressed, compress_type, folios[0], false); if (ret <= 0) { if (ret < 0) mapping_set_error(mapping, -EIO); goto free_pages; } /* * We aren't doing an inline extent. Round the compressed size up to a * block size boundary so the allocator does sane things. */ total_compressed = ALIGN(total_compressed, blocksize); /* * One last check to make sure the compression is really a win, compare * the page count read with the blocks on disk, compression must free at * least one sector. */ total_in = round_up(total_in, fs_info->sectorsize); if (total_compressed + blocksize > total_in) goto mark_incompressible; /* * The async work queues will take care of doing actual allocation on * disk for these compressed pages, and will submit the bios. */ ret = add_async_extent(async_chunk, start, total_in, total_compressed, folios, nr_folios, compress_type); BUG_ON(ret); if (start + total_in < end) { start += total_in; cond_resched(); goto again; } return; mark_incompressible: if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) && !inode->prop_compress) inode->flags |= BTRFS_INODE_NOCOMPRESS; cleanup_and_bail_uncompressed: ret = add_async_extent(async_chunk, start, end - start + 1, 0, NULL, 0, BTRFS_COMPRESS_NONE); BUG_ON(ret); free_pages: if (folios) { for (i = 0; i < nr_folios; i++) { WARN_ON(folios[i]->mapping); btrfs_free_compr_folio(folios[i]); } kfree(folios); } } static void free_async_extent_pages(struct async_extent *async_extent) { int i; if (!async_extent->folios) return; for (i = 0; i < async_extent->nr_folios; i++) { WARN_ON(async_extent->folios[i]->mapping); btrfs_free_compr_folio(async_extent->folios[i]); } kfree(async_extent->folios); async_extent->nr_folios = 0; async_extent->folios = NULL; } static void submit_uncompressed_range(struct btrfs_inode *inode, struct async_extent *async_extent, struct folio *locked_folio) { u64 start = async_extent->start; u64 end = async_extent->start + async_extent->ram_size - 1; int ret; struct writeback_control wbc = { .sync_mode = WB_SYNC_ALL, .range_start = start, .range_end = end, .no_cgroup_owner = 1, }; wbc_attach_fdatawrite_inode(&wbc, &inode->vfs_inode); ret = run_delalloc_cow(inode, locked_folio, start, end, &wbc, false); wbc_detach_inode(&wbc); if (ret < 0) { btrfs_cleanup_ordered_extents(inode, locked_folio, start, end - start + 1); if (locked_folio) { const u64 page_start = folio_pos(locked_folio); folio_start_writeback(locked_folio); folio_end_writeback(locked_folio); btrfs_mark_ordered_io_finished(inode, locked_folio, page_start, PAGE_SIZE, !ret); mapping_set_error(locked_folio->mapping, ret); folio_unlock(locked_folio); } } } static void submit_one_async_extent(struct async_chunk *async_chunk, struct async_extent *async_extent, u64 *alloc_hint) { struct btrfs_inode *inode = async_chunk->inode; struct extent_io_tree *io_tree = &inode->io_tree; struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_ordered_extent *ordered; struct btrfs_file_extent file_extent; struct btrfs_key ins; struct folio *locked_folio = NULL; struct extent_state *cached = NULL; struct extent_map *em; int ret = 0; u64 start = async_extent->start; u64 end = async_extent->start + async_extent->ram_size - 1; if (async_chunk->blkcg_css) kthread_associate_blkcg(async_chunk->blkcg_css); /* * If async_chunk->locked_folio is in the async_extent range, we need to * handle it. */ if (async_chunk->locked_folio) { u64 locked_folio_start = folio_pos(async_chunk->locked_folio); u64 locked_folio_end = locked_folio_start + folio_size(async_chunk->locked_folio) - 1; if (!(start >= locked_folio_end || end <= locked_folio_start)) locked_folio = async_chunk->locked_folio; } if (async_extent->compress_type == BTRFS_COMPRESS_NONE) { submit_uncompressed_range(inode, async_extent, locked_folio); goto done; } ret = btrfs_reserve_extent(root, async_extent->ram_size, async_extent->compressed_size, async_extent->compressed_size, 0, *alloc_hint, &ins, 1, 1); if (ret) { /* * We can't reserve contiguous space for the compressed size. * Unlikely, but it's possible that we could have enough * non-contiguous space for the uncompressed size instead. So * fall back to uncompressed. */ submit_uncompressed_range(inode, async_extent, locked_folio); goto done; } lock_extent(io_tree, start, end, &cached); /* Here we're doing allocation and writeback of the compressed pages */ file_extent.disk_bytenr = ins.objectid; file_extent.disk_num_bytes = ins.offset; file_extent.ram_bytes = async_extent->ram_size; file_extent.num_bytes = async_extent->ram_size; file_extent.offset = 0; file_extent.compression = async_extent->compress_type; em = btrfs_create_io_em(inode, start, &file_extent, BTRFS_ORDERED_COMPRESSED); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out_free_reserve; } free_extent_map(em); ordered = btrfs_alloc_ordered_extent(inode, start, &file_extent, 1 << BTRFS_ORDERED_COMPRESSED); if (IS_ERR(ordered)) { btrfs_drop_extent_map_range(inode, start, end, false); ret = PTR_ERR(ordered); goto out_free_reserve; } btrfs_dec_block_group_reservations(fs_info, ins.objectid); /* Clear dirty, set writeback and unlock the pages. */ extent_clear_unlock_delalloc(inode, start, end, NULL, &cached, EXTENT_LOCKED | EXTENT_DELALLOC, PAGE_UNLOCK | PAGE_START_WRITEBACK); btrfs_submit_compressed_write(ordered, async_extent->folios, /* compressed_folios */ async_extent->nr_folios, async_chunk->write_flags, true); *alloc_hint = ins.objectid + ins.offset; done: if (async_chunk->blkcg_css) kthread_associate_blkcg(NULL); kfree(async_extent); return; out_free_reserve: btrfs_dec_block_group_reservations(fs_info, ins.objectid); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); mapping_set_error(inode->vfs_inode.i_mapping, -EIO); extent_clear_unlock_delalloc(inode, start, end, NULL, &cached, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK); free_async_extent_pages(async_extent); if (async_chunk->blkcg_css) kthread_associate_blkcg(NULL); btrfs_debug(fs_info, "async extent submission failed root=%lld inode=%llu start=%llu len=%llu ret=%d", btrfs_root_id(root), btrfs_ino(inode), start, async_extent->ram_size, ret); kfree(async_extent); } u64 btrfs_get_extent_allocation_hint(struct btrfs_inode *inode, u64 start, u64 num_bytes) { struct extent_map_tree *em_tree = &inode->extent_tree; struct extent_map *em; u64 alloc_hint = 0; read_lock(&em_tree->lock); em = search_extent_mapping(em_tree, start, num_bytes); if (em) { /* * if block start isn't an actual block number then find the * first block in this inode and use that as a hint. If that * block is also bogus then just don't worry about it. */ if (em->disk_bytenr >= EXTENT_MAP_LAST_BYTE) { free_extent_map(em); em = search_extent_mapping(em_tree, 0, 0); if (em && em->disk_bytenr < EXTENT_MAP_LAST_BYTE) alloc_hint = extent_map_block_start(em); if (em) free_extent_map(em); } else { alloc_hint = extent_map_block_start(em); free_extent_map(em); } } read_unlock(&em_tree->lock); return alloc_hint; } /* * when extent_io.c finds a delayed allocation range in the file, * the call backs end up in this code. The basic idea is to * allocate extents on disk for the range, and create ordered data structs * in ram to track those extents. * * locked_folio is the folio that writepage had locked already. We use * it to make sure we don't do extra locks or unlocks. * * When this function fails, it unlocks all pages except @locked_folio. * * When this function successfully creates an inline extent, it returns 1 and * unlocks all pages including locked_folio and starts I/O on them. * (In reality inline extents are limited to a single page, so locked_folio is * the only page handled anyway). * * When this function succeed and creates a normal extent, the page locking * status depends on the passed in flags: * * - If @keep_locked is set, all pages are kept locked. * - Else all pages except for @locked_folio are unlocked. * * When a failure happens in the second or later iteration of the * while-loop, the ordered extents created in previous iterations are kept * intact. So, the caller must clean them up by calling * btrfs_cleanup_ordered_extents(). See btrfs_run_delalloc_range() for * example. */ static noinline int cow_file_range(struct btrfs_inode *inode, struct folio *locked_folio, u64 start, u64 end, u64 *done_offset, bool keep_locked, bool no_inline) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct extent_state *cached = NULL; u64 alloc_hint = 0; u64 orig_start = start; u64 num_bytes; unsigned long ram_size; u64 cur_alloc_size = 0; u64 min_alloc_size; u64 blocksize = fs_info->sectorsize; struct btrfs_key ins; struct extent_map *em; unsigned clear_bits; unsigned long page_ops; bool extent_reserved = false; int ret = 0; if (btrfs_is_free_space_inode(inode)) { ret = -EINVAL; goto out_unlock; } num_bytes = ALIGN(end - start + 1, blocksize); num_bytes = max(blocksize, num_bytes); ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy)); inode_should_defrag(inode, start, end, num_bytes, SZ_64K); if (!no_inline) { /* lets try to make an inline extent */ ret = cow_file_range_inline(inode, locked_folio, start, end, 0, BTRFS_COMPRESS_NONE, NULL, false); if (ret <= 0) { /* * We succeeded, return 1 so the caller knows we're done * with this page and already handled the IO. * * If there was an error then cow_file_range_inline() has * already done the cleanup. */ if (ret == 0) ret = 1; goto done; } } alloc_hint = btrfs_get_extent_allocation_hint(inode, start, num_bytes); /* * Relocation relies on the relocated extents to have exactly the same * size as the original extents. Normally writeback for relocation data * extents follows a NOCOW path because relocation preallocates the * extents. However, due to an operation such as scrub turning a block * group to RO mode, it may fallback to COW mode, so we must make sure * an extent allocated during COW has exactly the requested size and can * not be split into smaller extents, otherwise relocation breaks and * fails during the stage where it updates the bytenr of file extent * items. */ if (btrfs_is_data_reloc_root(root)) min_alloc_size = num_bytes; else min_alloc_size = fs_info->sectorsize; while (num_bytes > 0) { struct btrfs_ordered_extent *ordered; struct btrfs_file_extent file_extent; cur_alloc_size = num_bytes; ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size, min_alloc_size, 0, alloc_hint, &ins, 1, 1); if (ret == -EAGAIN) { /* * btrfs_reserve_extent only returns -EAGAIN for zoned * file systems, which is an indication that there are * no active zones to allocate from at the moment. * * If this is the first loop iteration, wait for at * least one zone to finish before retrying the * allocation. Otherwise ask the caller to write out * the already allocated blocks before coming back to * us, or return -ENOSPC if it can't handle retries. */ ASSERT(btrfs_is_zoned(fs_info)); if (start == orig_start) { wait_on_bit_io(&inode->root->fs_info->flags, BTRFS_FS_NEED_ZONE_FINISH, TASK_UNINTERRUPTIBLE); continue; } if (done_offset) { *done_offset = start - 1; return 0; } ret = -ENOSPC; } if (ret < 0) goto out_unlock; cur_alloc_size = ins.offset; extent_reserved = true; ram_size = ins.offset; file_extent.disk_bytenr = ins.objectid; file_extent.disk_num_bytes = ins.offset; file_extent.num_bytes = ins.offset; file_extent.ram_bytes = ins.offset; file_extent.offset = 0; file_extent.compression = BTRFS_COMPRESS_NONE; lock_extent(&inode->io_tree, start, start + ram_size - 1, &cached); em = btrfs_create_io_em(inode, start, &file_extent, BTRFS_ORDERED_REGULAR); if (IS_ERR(em)) { unlock_extent(&inode->io_tree, start, start + ram_size - 1, &cached); ret = PTR_ERR(em); goto out_reserve; } free_extent_map(em); ordered = btrfs_alloc_ordered_extent(inode, start, &file_extent, 1 << BTRFS_ORDERED_REGULAR); if (IS_ERR(ordered)) { unlock_extent(&inode->io_tree, start, start + ram_size - 1, &cached); ret = PTR_ERR(ordered); goto out_drop_extent_cache; } if (btrfs_is_data_reloc_root(root)) { ret = btrfs_reloc_clone_csums(ordered); /* * Only drop cache here, and process as normal. * * We must not allow extent_clear_unlock_delalloc() * at out_unlock label to free meta of this ordered * extent, as its meta should be freed by * btrfs_finish_ordered_io(). * * So we must continue until @start is increased to * skip current ordered extent. */ if (ret) btrfs_drop_extent_map_range(inode, start, start + ram_size - 1, false); } btrfs_put_ordered_extent(ordered); btrfs_dec_block_group_reservations(fs_info, ins.objectid); /* * We're not doing compressed IO, don't unlock the first page * (which the caller expects to stay locked), don't clear any * dirty bits and don't set any writeback bits * * Do set the Ordered (Private2) bit so we know this page was * properly setup for writepage. */ page_ops = (keep_locked ? 0 : PAGE_UNLOCK); page_ops |= PAGE_SET_ORDERED; extent_clear_unlock_delalloc(inode, start, start + ram_size - 1, locked_folio, &cached, EXTENT_LOCKED | EXTENT_DELALLOC, page_ops); if (num_bytes < cur_alloc_size) num_bytes = 0; else num_bytes -= cur_alloc_size; alloc_hint = ins.objectid + ins.offset; start += cur_alloc_size; extent_reserved = false; /* * btrfs_reloc_clone_csums() error, since start is increased * extent_clear_unlock_delalloc() at out_unlock label won't * free metadata of current ordered extent, we're OK to exit. */ if (ret) goto out_unlock; } done: if (done_offset) *done_offset = end; return ret; out_drop_extent_cache: btrfs_drop_extent_map_range(inode, start, start + ram_size - 1, false); out_reserve: btrfs_dec_block_group_reservations(fs_info, ins.objectid); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); out_unlock: /* * Now, we have three regions to clean up: * * |-------(1)----|---(2)---|-------------(3)----------| * `- orig_start `- start `- start + cur_alloc_size `- end * * We process each region below. */ clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK; /* * For the range (1). We have already instantiated the ordered extents * for this region. They are cleaned up by * btrfs_cleanup_ordered_extents() in e.g, * btrfs_run_delalloc_range(). EXTENT_LOCKED | EXTENT_DELALLOC are * already cleared in the above loop. And, EXTENT_DELALLOC_NEW | * EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV are handled by the cleanup * function. * * However, in case of @keep_locked, we still need to unlock the pages * (except @locked_folio) to ensure all the pages are unlocked. */ if (keep_locked && orig_start < start) { if (!locked_folio) mapping_set_error(inode->vfs_inode.i_mapping, ret); extent_clear_unlock_delalloc(inode, orig_start, start - 1, locked_folio, NULL, 0, page_ops); } /* * At this point we're unlocked, we want to make sure we're only * clearing these flags under the extent lock, so lock the rest of the * range and clear everything up. */ lock_extent(&inode->io_tree, start, end, NULL); /* * For the range (2). If we reserved an extent for our delalloc range * (or a subrange) and failed to create the respective ordered extent, * then it means that when we reserved the extent we decremented the * extent's size from the data space_info's bytes_may_use counter and * incremented the space_info's bytes_reserved counter by the same * amount. We must make sure extent_clear_unlock_delalloc() does not try * to decrement again the data space_info's bytes_may_use counter, * therefore we do not pass it the flag EXTENT_CLEAR_DATA_RESV. */ if (extent_reserved) { extent_clear_unlock_delalloc(inode, start, start + cur_alloc_size - 1, locked_folio, &cached, clear_bits, page_ops); btrfs_qgroup_free_data(inode, NULL, start, cur_alloc_size, NULL); start += cur_alloc_size; } /* * For the range (3). We never touched the region. In addition to the * clear_bits above, we add EXTENT_CLEAR_DATA_RESV to release the data * space_info's bytes_may_use counter, reserved in * btrfs_check_data_free_space(). */ if (start < end) { clear_bits |= EXTENT_CLEAR_DATA_RESV; extent_clear_unlock_delalloc(inode, start, end, locked_folio, &cached, clear_bits, page_ops); btrfs_qgroup_free_data(inode, NULL, start, end - start + 1, NULL); } return ret; } /* * Phase two of compressed writeback. This is the ordered portion of the code, * which only gets called in the order the work was queued. We walk all the * async extents created by compress_file_range and send them down to the disk. * * If called with @do_free == true then it'll try to finish the work and free * the work struct eventually. */ static noinline void submit_compressed_extents(struct btrfs_work *work, bool do_free) { struct async_chunk *async_chunk = container_of(work, struct async_chunk, work); struct btrfs_fs_info *fs_info = btrfs_work_owner(work); struct async_extent *async_extent; unsigned long nr_pages; u64 alloc_hint = 0; if (do_free) { struct async_cow *async_cow; btrfs_add_delayed_iput(async_chunk->inode); if (async_chunk->blkcg_css) css_put(async_chunk->blkcg_css); async_cow = async_chunk->async_cow; if (atomic_dec_and_test(&async_cow->num_chunks)) kvfree(async_cow); return; } nr_pages = (async_chunk->end - async_chunk->start + PAGE_SIZE) >> PAGE_SHIFT; while (!list_empty(&async_chunk->extents)) { async_extent = list_entry(async_chunk->extents.next, struct async_extent, list); list_del(&async_extent->list); submit_one_async_extent(async_chunk, async_extent, &alloc_hint); } /* atomic_sub_return implies a barrier */ if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) < 5 * SZ_1M) cond_wake_up_nomb(&fs_info->async_submit_wait); } static bool run_delalloc_compressed(struct btrfs_inode *inode, struct folio *locked_folio, u64 start, u64 end, struct writeback_control *wbc) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct cgroup_subsys_state *blkcg_css = wbc_blkcg_css(wbc); struct async_cow *ctx; struct async_chunk *async_chunk; unsigned long nr_pages; u64 num_chunks = DIV_ROUND_UP(end - start, SZ_512K); int i; unsigned nofs_flag; const blk_opf_t write_flags = wbc_to_write_flags(wbc); nofs_flag = memalloc_nofs_save(); ctx = kvmalloc(struct_size(ctx, chunks, num_chunks), GFP_KERNEL); memalloc_nofs_restore(nofs_flag); if (!ctx) return false; set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &inode->runtime_flags); async_chunk = ctx->chunks; atomic_set(&ctx->num_chunks, num_chunks); for (i = 0; i < num_chunks; i++) { u64 cur_end = min(end, start + SZ_512K - 1); /* * igrab is called higher up in the call chain, take only the * lightweight reference for the callback lifetime */ ihold(&inode->vfs_inode); async_chunk[i].async_cow = ctx; async_chunk[i].inode = inode; async_chunk[i].start = start; async_chunk[i].end = cur_end; async_chunk[i].write_flags = write_flags; INIT_LIST_HEAD(&async_chunk[i].extents); /* * The locked_folio comes all the way from writepage and its * the original folio we were actually given. As we spread * this large delalloc region across multiple async_chunk * structs, only the first struct needs a pointer to * locked_folio. * * This way we don't need racey decisions about who is supposed * to unlock it. */ if (locked_folio) { /* * Depending on the compressibility, the pages might or * might not go through async. We want all of them to * be accounted against wbc once. Let's do it here * before the paths diverge. wbc accounting is used * only for foreign writeback detection and doesn't * need full accuracy. Just account the whole thing * against the first page. */ wbc_account_cgroup_owner(wbc, &locked_folio->page, cur_end - start); async_chunk[i].locked_folio = locked_folio; locked_folio = NULL; } else { async_chunk[i].locked_folio = NULL; } if (blkcg_css != blkcg_root_css) { css_get(blkcg_css); async_chunk[i].blkcg_css = blkcg_css; async_chunk[i].write_flags |= REQ_BTRFS_CGROUP_PUNT; } else { async_chunk[i].blkcg_css = NULL; } btrfs_init_work(&async_chunk[i].work, compress_file_range, submit_compressed_extents); nr_pages = DIV_ROUND_UP(cur_end - start, PAGE_SIZE); atomic_add(nr_pages, &fs_info->async_delalloc_pages); btrfs_queue_work(fs_info->delalloc_workers, &async_chunk[i].work); start = cur_end + 1; } return true; } /* * Run the delalloc range from start to end, and write back any dirty pages * covered by the range. */ static noinline int run_delalloc_cow(struct btrfs_inode *inode, struct folio *locked_folio, u64 start, u64 end, struct writeback_control *wbc, bool pages_dirty) { u64 done_offset = end; int ret; while (start <= end) { ret = cow_file_range(inode, locked_folio, start, end, &done_offset, true, false); if (ret) return ret; extent_write_locked_range(&inode->vfs_inode, locked_folio, start, done_offset, wbc, pages_dirty); start = done_offset + 1; } return 1; } static int fallback_to_cow(struct btrfs_inode *inode, struct folio *locked_folio, const u64 start, const u64 end) { const bool is_space_ino = btrfs_is_free_space_inode(inode); const bool is_reloc_ino = btrfs_is_data_reloc_root(inode->root); const u64 range_bytes = end + 1 - start; struct extent_io_tree *io_tree = &inode->io_tree; struct extent_state *cached_state = NULL; u64 range_start = start; u64 count; int ret; /* * If EXTENT_NORESERVE is set it means that when the buffered write was * made we had not enough available data space and therefore we did not * reserve data space for it, since we though we could do NOCOW for the * respective file range (either there is prealloc extent or the inode * has the NOCOW bit set). * * However when we need to fallback to COW mode (because for example the * block group for the corresponding extent was turned to RO mode by a * scrub or relocation) we need to do the following: * * 1) We increment the bytes_may_use counter of the data space info. * If COW succeeds, it allocates a new data extent and after doing * that it decrements the space info's bytes_may_use counter and * increments its bytes_reserved counter by the same amount (we do * this at btrfs_add_reserved_bytes()). So we need to increment the * bytes_may_use counter to compensate (when space is reserved at * buffered write time, the bytes_may_use counter is incremented); * * 2) We clear the EXTENT_NORESERVE bit from the range. We do this so * that if the COW path fails for any reason, it decrements (through * extent_clear_unlock_delalloc()) the bytes_may_use counter of the * data space info, which we incremented in the step above. * * If we need to fallback to cow and the inode corresponds to a free * space cache inode or an inode of the data relocation tree, we must * also increment bytes_may_use of the data space_info for the same * reason. Space caches and relocated data extents always get a prealloc * extent for them, however scrub or balance may have set the block * group that contains that extent to RO mode and therefore force COW * when starting writeback. */ lock_extent(io_tree, start, end, &cached_state); count = count_range_bits(io_tree, &range_start, end, range_bytes, EXTENT_NORESERVE, 0, NULL); if (count > 0 || is_space_ino || is_reloc_ino) { u64 bytes = count; struct btrfs_fs_info *fs_info = inode->root->fs_info; struct btrfs_space_info *sinfo = fs_info->data_sinfo; if (is_space_ino || is_reloc_ino) bytes = range_bytes; spin_lock(&sinfo->lock); btrfs_space_info_update_bytes_may_use(fs_info, sinfo, bytes); spin_unlock(&sinfo->lock); if (count > 0) clear_extent_bit(io_tree, start, end, EXTENT_NORESERVE, NULL); } unlock_extent(io_tree, start, end, &cached_state); /* * Don't try to create inline extents, as a mix of inline extent that * is written out and unlocked directly and a normal NOCOW extent * doesn't work. */ ret = cow_file_range(inode, locked_folio, start, end, NULL, false, true); ASSERT(ret != 1); return ret; } struct can_nocow_file_extent_args { /* Input fields. */ /* Start file offset of the range we want to NOCOW. */ u64 start; /* End file offset (inclusive) of the range we want to NOCOW. */ u64 end; bool writeback_path; bool strict; /* * Free the path passed to can_nocow_file_extent() once it's not needed * anymore. */ bool free_path; /* * Output fields. Only set when can_nocow_file_extent() returns 1. * The expected file extent for the NOCOW write. */ struct btrfs_file_extent file_extent; }; /* * Check if we can NOCOW the file extent that the path points to. * This function may return with the path released, so the caller should check * if path->nodes[0] is NULL or not if it needs to use the path afterwards. * * Returns: < 0 on error * 0 if we can not NOCOW * 1 if we can NOCOW */ static int can_nocow_file_extent(struct btrfs_path *path, struct btrfs_key *key, struct btrfs_inode *inode, struct can_nocow_file_extent_args *args) { const bool is_freespace_inode = btrfs_is_free_space_inode(inode); struct extent_buffer *leaf = path->nodes[0]; struct btrfs_root *root = inode->root; struct btrfs_file_extent_item *fi; struct btrfs_root *csum_root; u64 io_start; u64 extent_end; u8 extent_type; int can_nocow = 0; int ret = 0; bool nowait = path->nowait; fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); extent_type = btrfs_file_extent_type(leaf, fi); if (extent_type == BTRFS_FILE_EXTENT_INLINE) goto out; if (!(inode->flags & BTRFS_INODE_NODATACOW) && extent_type == BTRFS_FILE_EXTENT_REG) goto out; /* * If the extent was created before the generation where the last snapshot * for its subvolume was created, then this implies the extent is shared, * hence we must COW. */ if (!args->strict && btrfs_file_extent_generation(leaf, fi) <= btrfs_root_last_snapshot(&root->root_item)) goto out; /* An explicit hole, must COW. */ if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0) goto out; /* Compressed/encrypted/encoded extents must be COWed. */ if (btrfs_file_extent_compression(leaf, fi) || btrfs_file_extent_encryption(leaf, fi) || btrfs_file_extent_other_encoding(leaf, fi)) goto out; extent_end = btrfs_file_extent_end(path); args->file_extent.disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); args->file_extent.disk_num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); args->file_extent.ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); args->file_extent.offset = btrfs_file_extent_offset(leaf, fi); args->file_extent.compression = btrfs_file_extent_compression(leaf, fi); /* * The following checks can be expensive, as they need to take other * locks and do btree or rbtree searches, so release the path to avoid * blocking other tasks for too long. */ btrfs_release_path(path); ret = btrfs_cross_ref_exist(root, btrfs_ino(inode), key->offset - args->file_extent.offset, args->file_extent.disk_bytenr, args->strict, path); WARN_ON_ONCE(ret > 0 && is_freespace_inode); if (ret != 0) goto out; if (args->free_path) { /* * We don't need the path anymore, plus through the * btrfs_lookup_csums_list() call below we will end up allocating * another path. So free the path to avoid unnecessary extra * memory usage. */ btrfs_free_path(path); path = NULL; } /* If there are pending snapshots for this root, we must COW. */ if (args->writeback_path && !is_freespace_inode && atomic_read(&root->snapshot_force_cow)) goto out; args->file_extent.num_bytes = min(args->end + 1, extent_end) - args->start; args->file_extent.offset += args->start - key->offset; io_start = args->file_extent.disk_bytenr + args->file_extent.offset; /* * Force COW if csums exist in the range. This ensures that csums for a * given extent are either valid or do not exist. */ csum_root = btrfs_csum_root(root->fs_info, io_start); ret = btrfs_lookup_csums_list(csum_root, io_start, io_start + args->file_extent.num_bytes - 1, NULL, nowait); WARN_ON_ONCE(ret > 0 && is_freespace_inode); if (ret != 0) goto out; can_nocow = 1; out: if (args->free_path && path) btrfs_free_path(path); return ret < 0 ? ret : can_nocow; } /* * when nowcow writeback call back. This checks for snapshots or COW copies * of the extents that exist in the file, and COWs the file as required. * * If no cow copies or snapshots exist, we write directly to the existing * blocks on disk */ static noinline int run_delalloc_nocow(struct btrfs_inode *inode, struct folio *locked_folio, const u64 start, const u64 end) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct btrfs_root *root = inode->root; struct btrfs_path *path; u64 cow_start = (u64)-1; u64 cur_offset = start; int ret; bool check_prev = true; u64 ino = btrfs_ino(inode); struct can_nocow_file_extent_args nocow_args = { 0 }; /* * Normally on a zoned device we're only doing COW writes, but in case * of relocation on a zoned filesystem serializes I/O so that we're only * writing sequentially and can end up here as well. */ ASSERT(!btrfs_is_zoned(fs_info) || btrfs_is_data_reloc_root(root)); path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto error; } nocow_args.end = end; nocow_args.writeback_path = true; while (cur_offset <= end) { struct btrfs_block_group *nocow_bg = NULL; struct btrfs_ordered_extent *ordered; struct btrfs_key found_key; struct btrfs_file_extent_item *fi; struct extent_buffer *leaf; struct extent_state *cached_state = NULL; u64 extent_end; u64 nocow_end; int extent_type; bool is_prealloc; ret = btrfs_lookup_file_extent(NULL, root, path, ino, cur_offset, 0); if (ret < 0) goto error; /* * If there is no extent for our range when doing the initial * search, then go back to the previous slot as it will be the * one containing the search offset */ if (ret > 0 && path->slots[0] > 0 && check_prev) { leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); if (found_key.objectid == ino && found_key.type == BTRFS_EXTENT_DATA_KEY) path->slots[0]--; } check_prev = false; next_slot: /* Go to next leaf if we have exhausted the current one */ leaf = path->nodes[0]; if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto error; if (ret > 0) break; leaf = path->nodes[0]; } btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); /* Didn't find anything for our INO */ if (found_key.objectid > ino) break; /* * Keep searching until we find an EXTENT_ITEM or there are no * more extents for this inode */ if (WARN_ON_ONCE(found_key.objectid < ino) || found_key.type < BTRFS_EXTENT_DATA_KEY) { path->slots[0]++; goto next_slot; } /* Found key is not EXTENT_DATA_KEY or starts after req range */ if (found_key.type > BTRFS_EXTENT_DATA_KEY || found_key.offset > end) break; /* * If the found extent starts after requested offset, then * adjust extent_end to be right before this extent begins */ if (found_key.offset > cur_offset) { extent_end = found_key.offset; extent_type = 0; goto must_cow; } /* * Found extent which begins before our range and potentially * intersect it */ fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); extent_type = btrfs_file_extent_type(leaf, fi); /* If this is triggered then we have a memory corruption. */ ASSERT(extent_type < BTRFS_NR_FILE_EXTENT_TYPES); if (WARN_ON(extent_type >= BTRFS_NR_FILE_EXTENT_TYPES)) { ret = -EUCLEAN; goto error; } extent_end = btrfs_file_extent_end(path); /* * If the extent we got ends before our current offset, skip to * the next extent. */ if (extent_end <= cur_offset) { path->slots[0]++; goto next_slot; } nocow_args.start = cur_offset; ret = can_nocow_file_extent(path, &found_key, inode, &nocow_args); if (ret < 0) goto error; if (ret == 0) goto must_cow; ret = 0; nocow_bg = btrfs_inc_nocow_writers(fs_info, nocow_args.file_extent.disk_bytenr + nocow_args.file_extent.offset); if (!nocow_bg) { must_cow: /* * If we can't perform NOCOW writeback for the range, * then record the beginning of the range that needs to * be COWed. It will be written out before the next * NOCOW range if we find one, or when exiting this * loop. */ if (cow_start == (u64)-1) cow_start = cur_offset; cur_offset = extent_end; if (cur_offset > end) break; if (!path->nodes[0]) continue; path->slots[0]++; goto next_slot; } /* * COW range from cow_start to found_key.offset - 1. As the key * will contain the beginning of the first extent that can be * NOCOW, following one which needs to be COW'ed */ if (cow_start != (u64)-1) { ret = fallback_to_cow(inode, locked_folio, cow_start, found_key.offset - 1); cow_start = (u64)-1; if (ret) { btrfs_dec_nocow_writers(nocow_bg); goto error; } } nocow_end = cur_offset + nocow_args.file_extent.num_bytes - 1; lock_extent(&inode->io_tree, cur_offset, nocow_end, &cached_state); is_prealloc = extent_type == BTRFS_FILE_EXTENT_PREALLOC; if (is_prealloc) { struct extent_map *em; em = btrfs_create_io_em(inode, cur_offset, &nocow_args.file_extent, BTRFS_ORDERED_PREALLOC); if (IS_ERR(em)) { unlock_extent(&inode->io_tree, cur_offset, nocow_end, &cached_state); btrfs_dec_nocow_writers(nocow_bg); ret = PTR_ERR(em); goto error; } free_extent_map(em); } ordered = btrfs_alloc_ordered_extent(inode, cur_offset, &nocow_args.file_extent, is_prealloc ? (1 << BTRFS_ORDERED_PREALLOC) : (1 << BTRFS_ORDERED_NOCOW)); btrfs_dec_nocow_writers(nocow_bg); if (IS_ERR(ordered)) { if (is_prealloc) { btrfs_drop_extent_map_range(inode, cur_offset, nocow_end, false); } unlock_extent(&inode->io_tree, cur_offset, nocow_end, &cached_state); ret = PTR_ERR(ordered); goto error; } if (btrfs_is_data_reloc_root(root)) /* * Error handled later, as we must prevent * extent_clear_unlock_delalloc() in error handler * from freeing metadata of created ordered extent. */ ret = btrfs_reloc_clone_csums(ordered); btrfs_put_ordered_extent(ordered); extent_clear_unlock_delalloc(inode, cur_offset, nocow_end, locked_folio, &cached_state, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_CLEAR_DATA_RESV, PAGE_UNLOCK | PAGE_SET_ORDERED); cur_offset = extent_end; /* * btrfs_reloc_clone_csums() error, now we're OK to call error * handler, as metadata for created ordered extent will only * be freed by btrfs_finish_ordered_io(). */ if (ret) goto error; } btrfs_release_path(path); if (cur_offset <= end && cow_start == (u64)-1) cow_start = cur_offset; if (cow_start != (u64)-1) { cur_offset = end; ret = fallback_to_cow(inode, locked_folio, cow_start, end); cow_start = (u64)-1; if (ret) goto error; } btrfs_free_path(path); return 0; error: /* * If an error happened while a COW region is outstanding, cur_offset * needs to be reset to cow_start to ensure the COW region is unlocked * as well. */ if (cow_start != (u64)-1) cur_offset = cow_start; /* * We need to lock the extent here because we're clearing DELALLOC and * we're not locked at this point. */ if (cur_offset < end) { struct extent_state *cached = NULL; lock_extent(&inode->io_tree, cur_offset, end, &cached); extent_clear_unlock_delalloc(inode, cur_offset, end, locked_folio, &cached, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK); btrfs_qgroup_free_data(inode, NULL, cur_offset, end - cur_offset + 1, NULL); } btrfs_free_path(path); return ret; } static bool should_nocow(struct btrfs_inode *inode, u64 start, u64 end) { if (inode->flags & (BTRFS_INODE_NODATACOW | BTRFS_INODE_PREALLOC)) { if (inode->defrag_bytes && test_range_bit_exists(&inode->io_tree, start, end, EXTENT_DEFRAG)) return false; return true; } return false; } /* * Function to process delayed allocation (create CoW) for ranges which are * being touched for the first time. */ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct folio *locked_folio, u64 start, u64 end, struct writeback_control *wbc) { const bool zoned = btrfs_is_zoned(inode->root->fs_info); int ret; /* * The range must cover part of the @locked_folio, or a return of 1 * can confuse the caller. */ ASSERT(!(end <= folio_pos(locked_folio) || start >= folio_pos(locked_folio) + folio_size(locked_folio))); if (should_nocow(inode, start, end)) { ret = run_delalloc_nocow(inode, locked_folio, start, end); goto out; } if (btrfs_inode_can_compress(inode) && inode_need_compress(inode, start, end) && run_delalloc_compressed(inode, locked_folio, start, end, wbc)) return 1; if (zoned) ret = run_delalloc_cow(inode, locked_folio, start, end, wbc, true); else ret = cow_file_range(inode, locked_folio, start, end, NULL, false, false); out: if (ret < 0) btrfs_cleanup_ordered_extents(inode, locked_folio, start, end - start + 1); return ret; } void btrfs_split_delalloc_extent(struct btrfs_inode *inode, struct extent_state *orig, u64 split) { struct btrfs_fs_info *fs_info = inode->root->fs_info; u64 size; lockdep_assert_held(&inode->io_tree.lock); /* not delalloc, ignore it */ if (!(orig->state & EXTENT_DELALLOC)) return; size = orig->end - orig->start + 1; if (size > fs_info->max_extent_size) { u32 num_extents; u64 new_size; /* * See the explanation in btrfs_merge_delalloc_extent, the same * applies here, just in reverse. */ new_size = orig->end - split + 1; num_extents = count_max_extents(fs_info, new_size); new_size = split - orig->start; num_extents += count_max_extents(fs_info, new_size); if (count_max_extents(fs_info, size) >= num_extents) return; } spin_lock(&inode->lock); btrfs_mod_outstanding_extents(inode, 1); spin_unlock(&inode->lock); } /* * Handle merged delayed allocation extents so we can keep track of new extents * that are just merged onto old extents, such as when we are doing sequential * writes, so we can properly account for the metadata space we'll need. */ void btrfs_merge_delalloc_extent(struct btrfs_inode *inode, struct extent_state *new, struct extent_state *other) { struct btrfs_fs_info *fs_info = inode->root->fs_info; u64 new_size, old_size; u32 num_extents; lockdep_assert_held(&inode->io_tree.lock); /* not delalloc, ignore it */ if (!(other->state & EXTENT_DELALLOC)) return; if (new->start > other->start) new_size = new->end - other->start + 1; else new_size = other->end - new->start + 1; /* we're not bigger than the max, unreserve the space and go */ if (new_size <= fs_info->max_extent_size) { spin_lock(&inode->lock); btrfs_mod_outstanding_extents(inode, -1); spin_unlock(&inode->lock); return; } /* * We have to add up either side to figure out how many extents were * accounted for before we merged into one big extent. If the number of * extents we accounted for is <= the amount we need for the new range * then we can return, otherwise drop. Think of it like this * * [ 4k][MAX_SIZE] * * So we've grown the extent by a MAX_SIZE extent, this would mean we * need 2 outstanding extents, on one side we have 1 and the other side * we have 1 so they are == and we can return. But in this case * * [MAX_SIZE+4k][MAX_SIZE+4k] * * Each range on their own accounts for 2 extents, but merged together * they are only 3 extents worth of accounting, so we need to drop in * this case. */ old_size = other->end - other->start + 1; num_extents = count_max_extents(fs_info, old_size); old_size = new->end - new->start + 1; num_extents += count_max_extents(fs_info, old_size); if (count_max_extents(fs_info, new_size) >= num_extents) return; spin_lock(&inode->lock); btrfs_mod_outstanding_extents(inode, -1); spin_unlock(&inode->lock); } static void btrfs_add_delalloc_inode(struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; spin_lock(&root->delalloc_lock); ASSERT(list_empty(&inode->delalloc_inodes)); list_add_tail(&inode->delalloc_inodes, &root->delalloc_inodes); root->nr_delalloc_inodes++; if (root->nr_delalloc_inodes == 1) { spin_lock(&fs_info->delalloc_root_lock); ASSERT(list_empty(&root->delalloc_root)); list_add_tail(&root->delalloc_root, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); } spin_unlock(&root->delalloc_lock); } void btrfs_del_delalloc_inode(struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; lockdep_assert_held(&root->delalloc_lock); /* * We may be called after the inode was already deleted from the list, * namely in the transaction abort path btrfs_destroy_delalloc_inodes(), * and then later through btrfs_clear_delalloc_extent() while the inode * still has ->delalloc_bytes > 0. */ if (!list_empty(&inode->delalloc_inodes)) { list_del_init(&inode->delalloc_inodes); root->nr_delalloc_inodes--; if (!root->nr_delalloc_inodes) { ASSERT(list_empty(&root->delalloc_inodes)); spin_lock(&fs_info->delalloc_root_lock); ASSERT(!list_empty(&root->delalloc_root)); list_del_init(&root->delalloc_root); spin_unlock(&fs_info->delalloc_root_lock); } } } /* * Properly track delayed allocation bytes in the inode and to maintain the * list of inodes that have pending delalloc work to be done. */ void btrfs_set_delalloc_extent(struct btrfs_inode *inode, struct extent_state *state, u32 bits) { struct btrfs_fs_info *fs_info = inode->root->fs_info; lockdep_assert_held(&inode->io_tree.lock); if ((bits & EXTENT_DEFRAG) && !(bits & EXTENT_DELALLOC)) WARN_ON(1); /* * set_bit and clear bit hooks normally require _irqsave/restore * but in this case, we are only testing for the DELALLOC * bit, which is only set or cleared with irqs on */ if (!(state->state & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) { u64 len = state->end + 1 - state->start; u64 prev_delalloc_bytes; u32 num_extents = count_max_extents(fs_info, len); spin_lock(&inode->lock); btrfs_mod_outstanding_extents(inode, num_extents); spin_unlock(&inode->lock); /* For sanity tests */ if (btrfs_is_testing(fs_info)) return; percpu_counter_add_batch(&fs_info->delalloc_bytes, len, fs_info->delalloc_batch); spin_lock(&inode->lock); prev_delalloc_bytes = inode->delalloc_bytes; inode->delalloc_bytes += len; if (bits & EXTENT_DEFRAG) inode->defrag_bytes += len; spin_unlock(&inode->lock); /* * We don't need to be under the protection of the inode's lock, * because we are called while holding the inode's io_tree lock * and are therefore protected against concurrent calls of this * function and btrfs_clear_delalloc_extent(). */ if (!btrfs_is_free_space_inode(inode) && prev_delalloc_bytes == 0) btrfs_add_delalloc_inode(inode); } if (!(state->state & EXTENT_DELALLOC_NEW) && (bits & EXTENT_DELALLOC_NEW)) { spin_lock(&inode->lock); inode->new_delalloc_bytes += state->end + 1 - state->start; spin_unlock(&inode->lock); } } /* * Once a range is no longer delalloc this function ensures that proper * accounting happens. */ void btrfs_clear_delalloc_extent(struct btrfs_inode *inode, struct extent_state *state, u32 bits) { struct btrfs_fs_info *fs_info = inode->root->fs_info; u64 len = state->end + 1 - state->start; u32 num_extents = count_max_extents(fs_info, len); lockdep_assert_held(&inode->io_tree.lock); if ((state->state & EXTENT_DEFRAG) && (bits & EXTENT_DEFRAG)) { spin_lock(&inode->lock); inode->defrag_bytes -= len; spin_unlock(&inode->lock); } /* * set_bit and clear bit hooks normally require _irqsave/restore * but in this case, we are only testing for the DELALLOC * bit, which is only set or cleared with irqs on */ if ((state->state & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) { struct btrfs_root *root = inode->root; u64 new_delalloc_bytes; spin_lock(&inode->lock); btrfs_mod_outstanding_extents(inode, -num_extents); spin_unlock(&inode->lock); /* * We don't reserve metadata space for space cache inodes so we * don't need to call delalloc_release_metadata if there is an * error. */ if (bits & EXTENT_CLEAR_META_RESV && root != fs_info->tree_root) btrfs_delalloc_release_metadata(inode, len, true); /* For sanity tests. */ if (btrfs_is_testing(fs_info)) return; if (!btrfs_is_data_reloc_root(root) && !btrfs_is_free_space_inode(inode) && !(state->state & EXTENT_NORESERVE) && (bits & EXTENT_CLEAR_DATA_RESV)) btrfs_free_reserved_data_space_noquota(fs_info, len); percpu_counter_add_batch(&fs_info->delalloc_bytes, -len, fs_info->delalloc_batch); spin_lock(&inode->lock); inode->delalloc_bytes -= len; new_delalloc_bytes = inode->delalloc_bytes; spin_unlock(&inode->lock); /* * We don't need to be under the protection of the inode's lock, * because we are called while holding the inode's io_tree lock * and are therefore protected against concurrent calls of this * function and btrfs_set_delalloc_extent(). */ if (!btrfs_is_free_space_inode(inode) && new_delalloc_bytes == 0) { spin_lock(&root->delalloc_lock); btrfs_del_delalloc_inode(inode); spin_unlock(&root->delalloc_lock); } } if ((state->state & EXTENT_DELALLOC_NEW) && (bits & EXTENT_DELALLOC_NEW)) { spin_lock(&inode->lock); ASSERT(inode->new_delalloc_bytes >= len); inode->new_delalloc_bytes -= len; if (bits & EXTENT_ADD_INODE_BYTES) inode_add_bytes(&inode->vfs_inode, len); spin_unlock(&inode->lock); } } /* * given a list of ordered sums record them in the inode. This happens * at IO completion time based on sums calculated at bio submission time. */ static int add_pending_csums(struct btrfs_trans_handle *trans, struct list_head *list) { struct btrfs_ordered_sum *sum; struct btrfs_root *csum_root = NULL; int ret; list_for_each_entry(sum, list, list) { trans->adding_csums = true; if (!csum_root) csum_root = btrfs_csum_root(trans->fs_info, sum->logical); ret = btrfs_csum_file_blocks(trans, csum_root, sum); trans->adding_csums = false; if (ret) return ret; } return 0; } static int btrfs_find_new_delalloc_bytes(struct btrfs_inode *inode, const u64 start, const u64 len, struct extent_state **cached_state) { u64 search_start = start; const u64 end = start + len - 1; while (search_start < end) { const u64 search_len = end - search_start + 1; struct extent_map *em; u64 em_len; int ret = 0; em = btrfs_get_extent(inode, NULL, search_start, search_len); if (IS_ERR(em)) return PTR_ERR(em); if (em->disk_bytenr != EXTENT_MAP_HOLE) goto next; em_len = em->len; if (em->start < search_start) em_len -= search_start - em->start; if (em_len > search_len) em_len = search_len; ret = set_extent_bit(&inode->io_tree, search_start, search_start + em_len - 1, EXTENT_DELALLOC_NEW, cached_state); next: search_start = extent_map_end(em); free_extent_map(em); if (ret) return ret; } return 0; } int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end, unsigned int extra_bits, struct extent_state **cached_state) { WARN_ON(PAGE_ALIGNED(end)); if (start >= i_size_read(&inode->vfs_inode) && !(inode->flags & BTRFS_INODE_PREALLOC)) { /* * There can't be any extents following eof in this case so just * set the delalloc new bit for the range directly. */ extra_bits |= EXTENT_DELALLOC_NEW; } else { int ret; ret = btrfs_find_new_delalloc_bytes(inode, start, end + 1 - start, cached_state); if (ret) return ret; } return set_extent_bit(&inode->io_tree, start, end, EXTENT_DELALLOC | extra_bits, cached_state); } /* see btrfs_writepage_start_hook for details on why this is required */ struct btrfs_writepage_fixup { struct folio *folio; struct btrfs_inode *inode; struct btrfs_work work; }; static void btrfs_writepage_fixup_worker(struct btrfs_work *work) { struct btrfs_writepage_fixup *fixup = container_of(work, struct btrfs_writepage_fixup, work); struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; struct folio *folio = fixup->folio; struct btrfs_inode *inode = fixup->inode; struct btrfs_fs_info *fs_info = inode->root->fs_info; u64 page_start = folio_pos(folio); u64 page_end = folio_pos(folio) + folio_size(folio) - 1; int ret = 0; bool free_delalloc_space = true; /* * This is similar to page_mkwrite, we need to reserve the space before * we take the folio lock. */ ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, folio_size(folio)); again: folio_lock(folio); /* * Before we queued this fixup, we took a reference on the folio. * folio->mapping may go NULL, but it shouldn't be moved to a different * address space. */ if (!folio->mapping || !folio_test_dirty(folio) || !folio_test_checked(folio)) { /* * Unfortunately this is a little tricky, either * * 1) We got here and our folio had already been dealt with and * we reserved our space, thus ret == 0, so we need to just * drop our space reservation and bail. This can happen the * first time we come into the fixup worker, or could happen * while waiting for the ordered extent. * 2) Our folio was already dealt with, but we happened to get an * ENOSPC above from the btrfs_delalloc_reserve_space. In * this case we obviously don't have anything to release, but * because the folio was already dealt with we don't want to * mark the folio with an error, so make sure we're resetting * ret to 0. This is why we have this check _before_ the ret * check, because we do not want to have a surprise ENOSPC * when the folio was already properly dealt with. */ if (!ret) { btrfs_delalloc_release_extents(inode, folio_size(folio)); btrfs_delalloc_release_space(inode, data_reserved, page_start, folio_size(folio), true); } ret = 0; goto out_page; } /* * We can't mess with the folio state unless it is locked, so now that * it is locked bail if we failed to make our space reservation. */ if (ret) goto out_page; lock_extent(&inode->io_tree, page_start, page_end, &cached_state); /* already ordered? We're done */ if (folio_test_ordered(folio)) goto out_reserved; ordered = btrfs_lookup_ordered_range(inode, page_start, PAGE_SIZE); if (ordered) { unlock_extent(&inode->io_tree, page_start, page_end, &cached_state); folio_unlock(folio); btrfs_start_ordered_extent(ordered); btrfs_put_ordered_extent(ordered); goto again; } ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, &cached_state); if (ret) goto out_reserved; /* * Everything went as planned, we're now the owner of a dirty page with * delayed allocation bits set and space reserved for our COW * destination. * * The page was dirty when we started, nothing should have cleaned it. */ BUG_ON(!folio_test_dirty(folio)); free_delalloc_space = false; out_reserved: btrfs_delalloc_release_extents(inode, PAGE_SIZE); if (free_delalloc_space) btrfs_delalloc_release_space(inode, data_reserved, page_start, PAGE_SIZE, true); unlock_extent(&inode->io_tree, page_start, page_end, &cached_state); out_page: if (ret) { /* * We hit ENOSPC or other errors. Update the mapping and page * to reflect the errors and clean the page. */ mapping_set_error(folio->mapping, ret); btrfs_mark_ordered_io_finished(inode, folio, page_start, folio_size(folio), !ret); folio_clear_dirty_for_io(folio); } btrfs_folio_clear_checked(fs_info, folio, page_start, PAGE_SIZE); folio_unlock(folio); folio_put(folio); kfree(fixup); extent_changeset_free(data_reserved); /* * As a precaution, do a delayed iput in case it would be the last iput * that could need flushing space. Recursing back to fixup worker would * deadlock. */ btrfs_add_delayed_iput(inode); } /* * There are a few paths in the higher layers of the kernel that directly * set the folio dirty bit without asking the filesystem if it is a * good idea. This causes problems because we want to make sure COW * properly happens and the data=ordered rules are followed. * * In our case any range that doesn't have the ORDERED bit set * hasn't been properly setup for IO. We kick off an async process * to fix it up. The async helper will wait for ordered extents, set * the delalloc bit and make it safe to write the folio. */ int btrfs_writepage_cow_fixup(struct folio *folio) { struct inode *inode = folio->mapping->host; struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); struct btrfs_writepage_fixup *fixup; /* This folio has ordered extent covering it already */ if (folio_test_ordered(folio)) return 0; /* * folio_checked is set below when we create a fixup worker for this * folio, don't try to create another one if we're already * folio_test_checked. * * The extent_io writepage code will redirty the foio if we send back * EAGAIN. */ if (folio_test_checked(folio)) return -EAGAIN; fixup = kzalloc(sizeof(*fixup), GFP_NOFS); if (!fixup) return -EAGAIN; /* * We are already holding a reference to this inode from * write_cache_pages. We need to hold it because the space reservation * takes place outside of the folio lock, and we can't trust * page->mapping outside of the folio lock. */ ihold(inode); btrfs_folio_set_checked(fs_info, folio, folio_pos(folio), folio_size(folio)); folio_get(folio); btrfs_init_work(&fixup->work, btrfs_writepage_fixup_worker, NULL); fixup->folio = folio; fixup->inode = BTRFS_I(inode); btrfs_queue_work(fs_info->fixup_workers, &fixup->work); return -EAGAIN; } static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, struct btrfs_inode *inode, u64 file_pos, struct btrfs_file_extent_item *stack_fi, const bool update_inode_bytes, u64 qgroup_reserved) { struct btrfs_root *root = inode->root; const u64 sectorsize = root->fs_info->sectorsize; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key ins; u64 disk_num_bytes = btrfs_stack_file_extent_disk_num_bytes(stack_fi); u64 disk_bytenr = btrfs_stack_file_extent_disk_bytenr(stack_fi); u64 offset = btrfs_stack_file_extent_offset(stack_fi); u64 num_bytes = btrfs_stack_file_extent_num_bytes(stack_fi); u64 ram_bytes = btrfs_stack_file_extent_ram_bytes(stack_fi); struct btrfs_drop_extents_args drop_args = { 0 }; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* * we may be replacing one extent in the tree with another. * The new extent is pinned in the extent map, and we don't want * to drop it from the cache until it is completely in the btree. * * So, tell btrfs_drop_extents to leave this extent in the cache. * the caller is expected to unpin it and allow it to be merged * with the others. */ drop_args.path = path; drop_args.start = file_pos; drop_args.end = file_pos + num_bytes; drop_args.replace_extent = true; drop_args.extent_item_size = sizeof(*stack_fi); ret = btrfs_drop_extents(trans, root, inode, &drop_args); if (ret) goto out; if (!drop_args.extent_inserted) { ins.objectid = btrfs_ino(inode); ins.offset = file_pos; ins.type = BTRFS_EXTENT_DATA_KEY; ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*stack_fi)); if (ret) goto out; } leaf = path->nodes[0]; btrfs_set_stack_file_extent_generation(stack_fi, trans->transid); write_extent_buffer(leaf, stack_fi, btrfs_item_ptr_offset(leaf, path->slots[0]), sizeof(struct btrfs_file_extent_item)); btrfs_mark_buffer_dirty(trans, leaf); btrfs_release_path(path); /* * If we dropped an inline extent here, we know the range where it is * was not marked with the EXTENT_DELALLOC_NEW bit, so we update the * number of bytes only for that range containing the inline extent. * The remaining of the range will be processed when clearning the * EXTENT_DELALLOC_BIT bit through the ordered extent completion. */ if (file_pos == 0 && !IS_ALIGNED(drop_args.bytes_found, sectorsize)) { u64 inline_size = round_down(drop_args.bytes_found, sectorsize); inline_size = drop_args.bytes_found - inline_size; btrfs_update_inode_bytes(inode, sectorsize, inline_size); drop_args.bytes_found -= inline_size; num_bytes -= sectorsize; } if (update_inode_bytes) btrfs_update_inode_bytes(inode, num_bytes, drop_args.bytes_found); ins.objectid = disk_bytenr; ins.offset = disk_num_bytes; ins.type = BTRFS_EXTENT_ITEM_KEY; ret = btrfs_inode_set_file_extent_range(inode, file_pos, ram_bytes); if (ret) goto out; ret = btrfs_alloc_reserved_file_extent(trans, root, btrfs_ino(inode), file_pos - offset, qgroup_reserved, &ins); out: btrfs_free_path(path); return ret; } static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info, u64 start, u64 len) { struct btrfs_block_group *cache; cache = btrfs_lookup_block_group(fs_info, start); ASSERT(cache); spin_lock(&cache->lock); cache->delalloc_bytes -= len; spin_unlock(&cache->lock); btrfs_put_block_group(cache); } static int insert_ordered_extent_file_extent(struct btrfs_trans_handle *trans, struct btrfs_ordered_extent *oe) { struct btrfs_file_extent_item stack_fi; bool update_inode_bytes; u64 num_bytes = oe->num_bytes; u64 ram_bytes = oe->ram_bytes; memset(&stack_fi, 0, sizeof(stack_fi)); btrfs_set_stack_file_extent_type(&stack_fi, BTRFS_FILE_EXTENT_REG); btrfs_set_stack_file_extent_disk_bytenr(&stack_fi, oe->disk_bytenr); btrfs_set_stack_file_extent_disk_num_bytes(&stack_fi, oe->disk_num_bytes); btrfs_set_stack_file_extent_offset(&stack_fi, oe->offset); if (test_bit(BTRFS_ORDERED_TRUNCATED, &oe->flags)) num_bytes = oe->truncated_len; btrfs_set_stack_file_extent_num_bytes(&stack_fi, num_bytes); btrfs_set_stack_file_extent_ram_bytes(&stack_fi, ram_bytes); btrfs_set_stack_file_extent_compression(&stack_fi, oe->compress_type); /* Encryption and other encoding is reserved and all 0 */ /* * For delalloc, when completing an ordered extent we update the inode's * bytes when clearing the range in the inode's io tree, so pass false * as the argument 'update_inode_bytes' to insert_reserved_file_extent(), * except if the ordered extent was truncated. */ update_inode_bytes = test_bit(BTRFS_ORDERED_DIRECT, &oe->flags) || test_bit(BTRFS_ORDERED_ENCODED, &oe->flags) || test_bit(BTRFS_ORDERED_TRUNCATED, &oe->flags); return insert_reserved_file_extent(trans, oe->inode, oe->file_offset, &stack_fi, update_inode_bytes, oe->qgroup_rsv); } /* * As ordered data IO finishes, this gets called so we can finish * an ordered extent if the range of bytes in the file it covers are * fully written. */ int btrfs_finish_one_ordered(struct btrfs_ordered_extent *ordered_extent) { struct btrfs_inode *inode = ordered_extent->inode; struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans = NULL; struct extent_io_tree *io_tree = &inode->io_tree; struct extent_state *cached_state = NULL; u64 start, end; int compress_type = 0; int ret = 0; u64 logical_len = ordered_extent->num_bytes; bool freespace_inode; bool truncated = false; bool clear_reserved_extent = true; unsigned int clear_bits = EXTENT_DEFRAG; start = ordered_extent->file_offset; end = start + ordered_extent->num_bytes - 1; if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_ENCODED, &ordered_extent->flags)) clear_bits |= EXTENT_DELALLOC_NEW; freespace_inode = btrfs_is_free_space_inode(inode); if (!freespace_inode) btrfs_lockdep_acquire(fs_info, btrfs_ordered_extent); if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) { ret = -EIO; goto out; } if (btrfs_is_zoned(fs_info)) btrfs_zone_finish_endio(fs_info, ordered_extent->disk_bytenr, ordered_extent->disk_num_bytes); if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) { truncated = true; logical_len = ordered_extent->truncated_len; /* Truncated the entire extent, don't bother adding */ if (!logical_len) goto out; } if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ btrfs_inode_safe_disk_i_size_write(inode, 0); if (freespace_inode) trans = btrfs_join_transaction_spacecache(root); else trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } trans->block_rsv = &inode->block_rsv; ret = btrfs_update_inode_fallback(trans, inode); if (ret) /* -ENOMEM or corruption */ btrfs_abort_transaction(trans, ret); ret = btrfs_insert_raid_extent(trans, ordered_extent); if (ret) btrfs_abort_transaction(trans, ret); goto out; } clear_bits |= EXTENT_LOCKED; lock_extent(io_tree, start, end, &cached_state); if (freespace_inode) trans = btrfs_join_transaction_spacecache(root); else trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } trans->block_rsv = &inode->block_rsv; ret = btrfs_insert_raid_extent(trans, ordered_extent); if (ret) goto out; if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) compress_type = ordered_extent->compress_type; if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { BUG_ON(compress_type); ret = btrfs_mark_extent_written(trans, inode, ordered_extent->file_offset, ordered_extent->file_offset + logical_len); btrfs_zoned_release_data_reloc_bg(fs_info, ordered_extent->disk_bytenr, ordered_extent->disk_num_bytes); } else { BUG_ON(root == fs_info->tree_root); ret = insert_ordered_extent_file_extent(trans, ordered_extent); if (!ret) { clear_reserved_extent = false; btrfs_release_delalloc_bytes(fs_info, ordered_extent->disk_bytenr, ordered_extent->disk_num_bytes); } } if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out; } ret = unpin_extent_cache(inode, ordered_extent->file_offset, ordered_extent->num_bytes, trans->transid); if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out; } ret = add_pending_csums(trans, &ordered_extent->list); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } /* * If this is a new delalloc range, clear its new delalloc flag to * update the inode's number of bytes. This needs to be done first * before updating the inode item. */ if ((clear_bits & EXTENT_DELALLOC_NEW) && !test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) clear_extent_bit(&inode->io_tree, start, end, EXTENT_DELALLOC_NEW | EXTENT_ADD_INODE_BYTES, &cached_state); btrfs_inode_safe_disk_i_size_write(inode, 0); ret = btrfs_update_inode_fallback(trans, inode); if (ret) { /* -ENOMEM or corruption */ btrfs_abort_transaction(trans, ret); goto out; } out: clear_extent_bit(&inode->io_tree, start, end, clear_bits, &cached_state); if (trans) btrfs_end_transaction(trans); if (ret || truncated) { u64 unwritten_start = start; /* * If we failed to finish this ordered extent for any reason we * need to make sure BTRFS_ORDERED_IOERR is set on the ordered * extent, and mark the inode with the error if it wasn't * already set. Any error during writeback would have already * set the mapping error, so we need to set it if we're the ones * marking this ordered extent as failed. */ if (ret) btrfs_mark_ordered_extent_error(ordered_extent); if (truncated) unwritten_start += logical_len; clear_extent_uptodate(io_tree, unwritten_start, end, NULL); /* * Drop extent maps for the part of the extent we didn't write. * * We have an exception here for the free_space_inode, this is * because when we do btrfs_get_extent() on the free space inode * we will search the commit root. If this is a new block group * we won't find anything, and we will trip over the assert in * writepage where we do ASSERT(em->block_start != * EXTENT_MAP_HOLE). * * Theoretically we could also skip this for any NOCOW extent as * we don't mess with the extent map tree in the NOCOW case, but * for now simply skip this if we are the free space inode. */ if (!btrfs_is_free_space_inode(inode)) btrfs_drop_extent_map_range(inode, unwritten_start, end, false); /* * If the ordered extent had an IOERR or something else went * wrong we need to return the space for this ordered extent * back to the allocator. We only free the extent in the * truncated case if we didn't write out the extent at all. * * If we made it past insert_reserved_file_extent before we * errored out then we don't need to do this as the accounting * has already been done. */ if ((ret || !logical_len) && clear_reserved_extent && !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { /* * Discard the range before returning it back to the * free space pool */ if (ret && btrfs_test_opt(fs_info, DISCARD_SYNC)) btrfs_discard_extent(fs_info, ordered_extent->disk_bytenr, ordered_extent->disk_num_bytes, NULL); btrfs_free_reserved_extent(fs_info, ordered_extent->disk_bytenr, ordered_extent->disk_num_bytes, 1); /* * Actually free the qgroup rsv which was released when * the ordered extent was created. */ btrfs_qgroup_free_refroot(fs_info, btrfs_root_id(inode->root), ordered_extent->qgroup_rsv, BTRFS_QGROUP_RSV_DATA); } } /* * This needs to be done to make sure anybody waiting knows we are done * updating everything for this ordered extent. */ btrfs_remove_ordered_extent(inode, ordered_extent); /* once for us */ btrfs_put_ordered_extent(ordered_extent); /* once for the tree */ btrfs_put_ordered_extent(ordered_extent); return ret; } int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered) { if (btrfs_is_zoned(ordered->inode->root->fs_info) && !test_bit(BTRFS_ORDERED_IOERR, &ordered->flags) && list_empty(&ordered->bioc_list)) btrfs_finish_ordered_zoned(ordered); return btrfs_finish_one_ordered(ordered); } /* * Verify the checksum for a single sector without any extra action that depend * on the type of I/O. */ int btrfs_check_sector_csum(struct btrfs_fs_info *fs_info, struct page *page, u32 pgoff, u8 *csum, const u8 * const csum_expected) { SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); char *kaddr; ASSERT(pgoff + fs_info->sectorsize <= PAGE_SIZE); shash->tfm = fs_info->csum_shash; kaddr = kmap_local_page(page) + pgoff; crypto_shash_digest(shash, kaddr, fs_info->sectorsize, csum); kunmap_local(kaddr); if (memcmp(csum, csum_expected, fs_info->csum_size)) return -EIO; return 0; } /* * Verify the checksum of a single data sector. * * @bbio: btrfs_io_bio which contains the csum * @dev: device the sector is on * @bio_offset: offset to the beginning of the bio (in bytes) * @bv: bio_vec to check * * Check if the checksum on a data block is valid. When a checksum mismatch is * detected, report the error and fill the corrupted range with zero. * * Return %true if the sector is ok or had no checksum to start with, else %false. */ bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev, u32 bio_offset, struct bio_vec *bv) { struct btrfs_inode *inode = bbio->inode; struct btrfs_fs_info *fs_info = inode->root->fs_info; u64 file_offset = bbio->file_offset + bio_offset; u64 end = file_offset + bv->bv_len - 1; u8 *csum_expected; u8 csum[BTRFS_CSUM_SIZE]; ASSERT(bv->bv_len == fs_info->sectorsize); if (!bbio->csum) return true; if (btrfs_is_data_reloc_root(inode->root) && test_range_bit(&inode->io_tree, file_offset, end, EXTENT_NODATASUM, NULL)) { /* Skip the range without csum for data reloc inode */ clear_extent_bits(&inode->io_tree, file_offset, end, EXTENT_NODATASUM); return true; } csum_expected = bbio->csum + (bio_offset >> fs_info->sectorsize_bits) * fs_info->csum_size; if (btrfs_check_sector_csum(fs_info, bv->bv_page, bv->bv_offset, csum, csum_expected)) goto zeroit; return true; zeroit: btrfs_print_data_csum_error(inode, file_offset, csum, csum_expected, bbio->mirror_num); if (dev) btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS); memzero_bvec(bv); return false; } /* * Perform a delayed iput on @inode. * * @inode: The inode we want to perform iput on * * This function uses the generic vfs_inode::i_count to track whether we should * just decrement it (in case it's > 1) or if this is the last iput then link * the inode to the delayed iput machinery. Delayed iputs are processed at * transaction commit time/superblock commit/cleaner kthread. */ void btrfs_add_delayed_iput(struct btrfs_inode *inode) { struct btrfs_fs_info *fs_info = inode->root->fs_info; unsigned long flags; if (atomic_add_unless(&inode->vfs_inode.i_count, -1, 1)) return; atomic_inc(&fs_info->nr_delayed_iputs); /* * Need to be irq safe here because we can be called from either an irq * context (see bio.c and btrfs_put_ordered_extent()) or a non-irq * context. */ spin_lock_irqsave(&fs_info->delayed_iput_lock, flags); ASSERT(list_empty(&inode->delayed_iput)); list_add_tail(&inode->delayed_iput, &fs_info->delayed_iputs); spin_unlock_irqrestore(&fs_info->delayed_iput_lock, flags); if (!test_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags)) wake_up_process(fs_info->cleaner_kthread); } static void run_delayed_iput_locked(struct btrfs_fs_info *fs_info, struct btrfs_inode *inode) { list_del_init(&inode->delayed_iput); spin_unlock_irq(&fs_info->delayed_iput_lock); iput(&inode->vfs_inode); if (atomic_dec_and_test(&fs_info->nr_delayed_iputs)) wake_up(&fs_info->delayed_iputs_wait); spin_lock_irq(&fs_info->delayed_iput_lock); } static void btrfs_run_delayed_iput(struct btrfs_fs_info *fs_info, struct btrfs_inode *inode) { if (!list_empty(&inode->delayed_iput)) { spin_lock_irq(&fs_info->delayed_iput_lock); if (!list_empty(&inode->delayed_iput)) run_delayed_iput_locked(fs_info, inode); spin_unlock_irq(&fs_info->delayed_iput_lock); } } void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info) { /* * btrfs_put_ordered_extent() can run in irq context (see bio.c), which * calls btrfs_add_delayed_iput() and that needs to lock * fs_info->delayed_iput_lock. So we need to disable irqs here to * prevent a deadlock. */ spin_lock_irq(&fs_info->delayed_iput_lock); while (!list_empty(&fs_info->delayed_iputs)) { struct btrfs_inode *inode; inode = list_first_entry(&fs_info->delayed_iputs, struct btrfs_inode, delayed_iput); run_delayed_iput_locked(fs_info, inode); if (need_resched()) { spin_unlock_irq(&fs_info->delayed_iput_lock); cond_resched(); spin_lock_irq(&fs_info->delayed_iput_lock); } } spin_unlock_irq(&fs_info->delayed_iput_lock); } /* * Wait for flushing all delayed iputs * * @fs_info: the filesystem * * This will wait on any delayed iputs that are currently running with KILLABLE * set. Once they are all done running we will return, unless we are killed in * which case we return EINTR. This helps in user operations like fallocate etc * that might get blocked on the iputs. * * Return EINTR if we were killed, 0 if nothing's pending */ int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info) { int ret = wait_event_killable(fs_info->delayed_iputs_wait, atomic_read(&fs_info->nr_delayed_iputs) == 0); if (ret) return -EINTR; return 0; } /* * This creates an orphan entry for the given inode in case something goes wrong * in the middle of an unlink. */ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { int ret; ret = btrfs_insert_orphan_item(trans, inode->root, btrfs_ino(inode)); if (ret && ret != -EEXIST) { btrfs_abort_transaction(trans, ret); return ret; } return 0; } /* * We have done the delete so we can go ahead and remove the orphan item for * this particular inode. */ static int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { return btrfs_del_orphan_item(trans, inode->root, btrfs_ino(inode)); } /* * this cleans up any orphans that may be left on the list from the last use * of this root. */ int btrfs_orphan_cleanup(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key, found_key; struct btrfs_trans_handle *trans; struct inode *inode; u64 last_objectid = 0; int ret = 0, nr_unlink = 0; if (test_and_set_bit(BTRFS_ROOT_ORPHAN_CLEANUP, &root->state)) return 0; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } path->reada = READA_BACK; key.objectid = BTRFS_ORPHAN_OBJECTID; key.type = BTRFS_ORPHAN_ITEM_KEY; key.offset = (u64)-1; while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; /* * if ret == 0 means we found what we were searching for, which * is weird, but possible, so only screw with path if we didn't * find the key and see if we have stuff that matches */ if (ret > 0) { ret = 0; if (path->slots[0] == 0) break; path->slots[0]--; } /* pull out the item */ leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); /* make sure the item matches what we want */ if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) break; if (found_key.type != BTRFS_ORPHAN_ITEM_KEY) break; /* release the path since we're done with it */ btrfs_release_path(path); /* * this is where we are basically btrfs_lookup, without the * crossing root thing. we store the inode number in the * offset of the orphan item. */ if (found_key.offset == last_objectid) { /* * We found the same inode as before. This means we were * not able to remove its items via eviction triggered * by an iput(). A transaction abort may have happened, * due to -ENOSPC for example, so try to grab the error * that lead to a transaction abort, if any. */ btrfs_err(fs_info, "Error removing orphan entry, stopping orphan cleanup"); ret = BTRFS_FS_ERROR(fs_info) ?: -EINVAL; goto out; } last_objectid = found_key.offset; found_key.objectid = found_key.offset; found_key.type = BTRFS_INODE_ITEM_KEY; found_key.offset = 0; inode = btrfs_iget(last_objectid, root); if (IS_ERR(inode)) { ret = PTR_ERR(inode); inode = NULL; if (ret != -ENOENT) goto out; } if (!inode && root == fs_info->tree_root) { struct btrfs_root *dead_root; int is_dead_root = 0; /* * This is an orphan in the tree root. Currently these * could come from 2 sources: * a) a root (snapshot/subvolume) deletion in progress * b) a free space cache inode * We need to distinguish those two, as the orphan item * for a root must not get deleted before the deletion * of the snapshot/subvolume's tree completes. * * btrfs_find_orphan_roots() ran before us, which has * found all deleted roots and loaded them into * fs_info->fs_roots_radix. So here we can find if an * orphan item corresponds to a deleted root by looking * up the root from that radix tree. */ spin_lock(&fs_info->fs_roots_radix_lock); dead_root = radix_tree_lookup(&fs_info->fs_roots_radix, (unsigned long)found_key.objectid); if (dead_root && btrfs_root_refs(&dead_root->root_item) == 0) is_dead_root = 1; spin_unlock(&fs_info->fs_roots_radix_lock); if (is_dead_root) { /* prevent this orphan from being found again */ key.offset = found_key.objectid - 1; continue; } } /* * If we have an inode with links, there are a couple of * possibilities: * * 1. We were halfway through creating fsverity metadata for the * file. In that case, the orphan item represents incomplete * fsverity metadata which must be cleaned up with * btrfs_drop_verity_items and deleting the orphan item. * 2. Old kernels (before v3.12) used to create an * orphan item for truncate indicating that there were possibly * extent items past i_size that needed to be deleted. In v3.12, * truncate was changed to update i_size in sync with the extent * items, but the (useless) orphan item was still created. Since * v4.18, we don't create the orphan item for truncate at all. * * So, this item could mean that we need to do a truncate, but * only if this filesystem was last used on a pre-v3.12 kernel * and was not cleanly unmounted. The odds of that are quite * slim, and it's a pain to do the truncate now, so just delete * the orphan item. * * It's also possible that this orphan item was supposed to be * deleted but wasn't. The inode number may have been reused, * but either way, we can delete the orphan item. */ if (!inode || inode->i_nlink) { if (inode) { ret = btrfs_drop_verity_items(BTRFS_I(inode)); iput(inode); inode = NULL; if (ret) goto out; } trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } btrfs_debug(fs_info, "auto deleting %Lu", found_key.objectid); ret = btrfs_del_orphan_item(trans, root, found_key.objectid); btrfs_end_transaction(trans); if (ret) goto out; continue; } nr_unlink++; /* this will do delete_inode and everything for us */ iput(inode); } /* release the path since we're done with it */ btrfs_release_path(path); if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) { trans = btrfs_join_transaction(root); if (!IS_ERR(trans)) btrfs_end_transaction(trans); } if (nr_unlink) btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink); out: if (ret) btrfs_err(fs_info, "could not do orphan cleanup %d", ret); btrfs_free_path(path); return ret; } /* * very simple check to peek ahead in the leaf looking for xattrs. If we * don't find any xattrs, we know there can't be any acls. * * slot is the slot the inode is in, objectid is the objectid of the inode */ static noinline int acls_after_inode_item(struct extent_buffer *leaf, int slot, u64 objectid, int *first_xattr_slot) { u32 nritems = btrfs_header_nritems(leaf); struct btrfs_key found_key; static u64 xattr_access = 0; static u64 xattr_default = 0; int scanned = 0; if (!xattr_access) { xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS, strlen(XATTR_NAME_POSIX_ACL_ACCESS)); xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT, strlen(XATTR_NAME_POSIX_ACL_DEFAULT)); } slot++; *first_xattr_slot = -1; while (slot < nritems) { btrfs_item_key_to_cpu(leaf, &found_key, slot); /* we found a different objectid, there must not be acls */ if (found_key.objectid != objectid) return 0; /* we found an xattr, assume we've got an acl */ if (found_key.type == BTRFS_XATTR_ITEM_KEY) { if (*first_xattr_slot == -1) *first_xattr_slot = slot; if (found_key.offset == xattr_access || found_key.offset == xattr_default) return 1; } /* * we found a key greater than an xattr key, there can't * be any acls later on */ if (found_key.type > BTRFS_XATTR_ITEM_KEY) return 0; slot++; scanned++; /* * it goes inode, inode backrefs, xattrs, extents, * so if there are a ton of hard links to an inode there can * be a lot of backrefs. Don't waste time searching too hard, * this is just an optimization */ if (scanned >= 8) break; } /* we hit the end of the leaf before we found an xattr or * something larger than an xattr. We have to assume the inode * has acls */ if (*first_xattr_slot == -1) *first_xattr_slot = slot; return 1; } static int btrfs_init_file_extent_tree(struct btrfs_inode *inode) { struct btrfs_fs_info *fs_info = inode->root->fs_info; if (WARN_ON_ONCE(inode->file_extent_tree)) return 0; if (btrfs_fs_incompat(fs_info, NO_HOLES)) return 0; if (!S_ISREG(inode->vfs_inode.i_mode)) return 0; if (btrfs_is_free_space_inode(inode)) return 0; inode->file_extent_tree = kmalloc(sizeof(struct extent_io_tree), GFP_KERNEL); if (!inode->file_extent_tree) return -ENOMEM; extent_io_tree_init(fs_info, inode->file_extent_tree, IO_TREE_INODE_FILE_EXTENT); /* Lockdep class is set only for the file extent tree. */ lockdep_set_class(&inode->file_extent_tree->lock, &file_extent_tree_class); return 0; } /* * read an inode from the btree into the in-memory inode */ static int btrfs_read_locked_inode(struct inode *inode, struct btrfs_path *in_path) { struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); struct btrfs_path *path = in_path; struct extent_buffer *leaf; struct btrfs_inode_item *inode_item; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key location; unsigned long ptr; int maybe_acls; u32 rdev; int ret; bool filled = false; int first_xattr_slot; ret = btrfs_init_file_extent_tree(BTRFS_I(inode)); if (ret) return ret; ret = btrfs_fill_inode(inode, &rdev); if (!ret) filled = true; if (!path) { path = btrfs_alloc_path(); if (!path) return -ENOMEM; } btrfs_get_inode_key(BTRFS_I(inode), &location); ret = btrfs_lookup_inode(NULL, root, path, &location, 0); if (ret) { if (path != in_path) btrfs_free_path(path); return ret; } leaf = path->nodes[0]; if (filled) goto cache_index; inode_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); inode->i_mode = btrfs_inode_mode(leaf, inode_item); set_nlink(inode, btrfs_inode_nlink(leaf, inode_item)); i_uid_write(inode, btrfs_inode_uid(leaf, inode_item)); i_gid_write(inode, btrfs_inode_gid(leaf, inode_item)); btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item)); btrfs_inode_set_file_extent_range(BTRFS_I(inode), 0, round_up(i_size_read(inode), fs_info->sectorsize)); inode_set_atime(inode, btrfs_timespec_sec(leaf, &inode_item->atime), btrfs_timespec_nsec(leaf, &inode_item->atime)); inode_set_mtime(inode, btrfs_timespec_sec(leaf, &inode_item->mtime), btrfs_timespec_nsec(leaf, &inode_item->mtime)); inode_set_ctime(inode, btrfs_timespec_sec(leaf, &inode_item->ctime), btrfs_timespec_nsec(leaf, &inode_item->ctime)); BTRFS_I(inode)->i_otime_sec = btrfs_timespec_sec(leaf, &inode_item->otime); BTRFS_I(inode)->i_otime_nsec = btrfs_timespec_nsec(leaf, &inode_item->otime); inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item); inode_set_iversion_queried(inode, btrfs_inode_sequence(leaf, inode_item)); inode->i_generation = BTRFS_I(inode)->generation; inode->i_rdev = 0; rdev = btrfs_inode_rdev(leaf, inode_item); if (S_ISDIR(inode->i_mode)) BTRFS_I(inode)->index_cnt = (u64)-1; btrfs_inode_split_flags(btrfs_inode_flags(leaf, inode_item), &BTRFS_I(inode)->flags, &BTRFS_I(inode)->ro_flags); cache_index: /* * If we were modified in the current generation and evicted from memory * and then re-read we need to do a full sync since we don't have any * idea about which extents were modified before we were evicted from * cache. * * This is required for both inode re-read from disk and delayed inode * in the delayed_nodes xarray. */ if (BTRFS_I(inode)->last_trans == btrfs_get_fs_generation(fs_info)) set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); /* * We don't persist the id of the transaction where an unlink operation * against the inode was last made. So here we assume the inode might * have been evicted, and therefore the exact value of last_unlink_trans * lost, and set it to last_trans to avoid metadata inconsistencies * between the inode and its parent if the inode is fsync'ed and the log * replayed. For example, in the scenario: * * touch mydir/foo * ln mydir/foo mydir/bar * sync * unlink mydir/bar * echo 2 > /proc/sys/vm/drop_caches # evicts inode * xfs_io -c fsync mydir/foo * * mount fs, triggers fsync log replay * * We must make sure that when we fsync our inode foo we also log its * parent inode, otherwise after log replay the parent still has the * dentry with the "bar" name but our inode foo has a link count of 1 * and doesn't have an inode ref with the name "bar" anymore. * * Setting last_unlink_trans to last_trans is a pessimistic approach, * but it guarantees correctness at the expense of occasional full * transaction commits on fsync if our inode is a directory, or if our * inode is not a directory, logging its parent unnecessarily. */ BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans; /* * Same logic as for last_unlink_trans. We don't persist the generation * of the last transaction where this inode was used for a reflink * operation, so after eviction and reloading the inode we must be * pessimistic and assume the last transaction that modified the inode. */ BTRFS_I(inode)->last_reflink_trans = BTRFS_I(inode)->last_trans; path->slots[0]++; if (inode->i_nlink != 1 || path->slots[0] >= btrfs_header_nritems(leaf)) goto cache_acl; btrfs_item_key_to_cpu(leaf, &location, path->slots[0]); if (location.objectid != btrfs_ino(BTRFS_I(inode))) goto cache_acl; ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); if (location.type == BTRFS_INODE_REF_KEY) { struct btrfs_inode_ref *ref; ref = (struct btrfs_inode_ref *)ptr; BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref); } else if (location.type == BTRFS_INODE_EXTREF_KEY) { struct btrfs_inode_extref *extref; extref = (struct btrfs_inode_extref *)ptr; BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf, extref); } cache_acl: /* * try to precache a NULL acl entry for files that don't have * any xattrs or acls */ maybe_acls = acls_after_inode_item(leaf, path->slots[0], btrfs_ino(BTRFS_I(inode)), &first_xattr_slot); if (first_xattr_slot != -1) { path->slots[0] = first_xattr_slot; ret = btrfs_load_inode_props(inode, path); if (ret) btrfs_err(fs_info, "error loading props for ino %llu (root %llu): %d", btrfs_ino(BTRFS_I(inode)), btrfs_root_id(root), ret); } if (path != in_path) btrfs_free_path(path); if (!maybe_acls) cache_no_acl(inode); switch (inode->i_mode & S_IFMT) { case S_IFREG: inode->i_mapping->a_ops = &btrfs_aops; inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; break; case S_IFDIR: inode->i_fop = &btrfs_dir_file_operations; inode->i_op = &btrfs_dir_inode_operations; break; case S_IFLNK: inode->i_op = &btrfs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_aops; break; default: inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, rdev); break; } btrfs_sync_inode_flags_to_i_flags(inode); return 0; } /* * given a leaf and an inode, copy the inode fields into the leaf */ static void fill_inode_item(struct btrfs_trans_handle *trans, struct extent_buffer *leaf, struct btrfs_inode_item *item, struct inode *inode) { struct btrfs_map_token token; u64 flags; btrfs_init_map_token(&token, leaf); btrfs_set_token_inode_uid(&token, item, i_uid_read(inode)); btrfs_set_token_inode_gid(&token, item, i_gid_read(inode)); btrfs_set_token_inode_size(&token, item, BTRFS_I(inode)->disk_i_size); btrfs_set_token_inode_mode(&token, item, inode->i_mode); btrfs_set_token_inode_nlink(&token, item, inode->i_nlink); btrfs_set_token_timespec_sec(&token, &item->atime, inode_get_atime_sec(inode)); btrfs_set_token_timespec_nsec(&token, &item->atime, inode_get_atime_nsec(inode)); btrfs_set_token_timespec_sec(&token, &item->mtime, inode_get_mtime_sec(inode)); btrfs_set_token_timespec_nsec(&token, &item->mtime, inode_get_mtime_nsec(inode)); btrfs_set_token_timespec_sec(&token, &item->ctime, inode_get_ctime_sec(inode)); btrfs_set_token_timespec_nsec(&token, &item->ctime, inode_get_ctime_nsec(inode)); btrfs_set_token_timespec_sec(&token, &item->otime, BTRFS_I(inode)->i_otime_sec); btrfs_set_token_timespec_nsec(&token, &item->otime, BTRFS_I(inode)->i_otime_nsec); btrfs_set_token_inode_nbytes(&token, item, inode_get_bytes(inode)); btrfs_set_token_inode_generation(&token, item, BTRFS_I(inode)->generation); btrfs_set_token_inode_sequence(&token, item, inode_peek_iversion(inode)); btrfs_set_token_inode_transid(&token, item, trans->transid); btrfs_set_token_inode_rdev(&token, item, inode->i_rdev); flags = btrfs_inode_combine_flags(BTRFS_I(inode)->flags, BTRFS_I(inode)->ro_flags); btrfs_set_token_inode_flags(&token, item, flags); btrfs_set_token_inode_block_group(&token, item, 0); } /* * copy everything in the in-memory inode into the btree. */ static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { struct btrfs_inode_item *inode_item; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; btrfs_get_inode_key(inode, &key); ret = btrfs_lookup_inode(trans, inode->root, path, &key, 1); if (ret) { if (ret > 0) ret = -ENOENT; goto failed; } leaf = path->nodes[0]; inode_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); fill_inode_item(trans, leaf, inode_item, &inode->vfs_inode); btrfs_mark_buffer_dirty(trans, leaf); btrfs_set_inode_last_trans(trans, inode); ret = 0; failed: btrfs_free_path(path); return ret; } /* * copy everything in the in-memory inode into the btree. */ int btrfs_update_inode(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; int ret; /* * If the inode is a free space inode, we can deadlock during commit * if we put it into the delayed code. * * The data relocation inode should also be directly updated * without delay */ if (!btrfs_is_free_space_inode(inode) && !btrfs_is_data_reloc_root(root) && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) { btrfs_update_root_times(trans, root); ret = btrfs_delayed_update_inode(trans, inode); if (!ret) btrfs_set_inode_last_trans(trans, inode); return ret; } return btrfs_update_inode_item(trans, inode); } int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, struct btrfs_inode *inode) { int ret; ret = btrfs_update_inode(trans, inode); if (ret == -ENOSPC) return btrfs_update_inode_item(trans, inode); return ret; } /* * unlink helper that gets used here in inode.c and in the tree logging * recovery code. It remove a link in a directory with a given name, and * also drops the back refs in the inode to the directory */ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans, struct btrfs_inode *dir, struct btrfs_inode *inode, const struct fscrypt_str *name, struct btrfs_rename_ctx *rename_ctx) { struct btrfs_root *root = dir->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; int ret = 0; struct btrfs_dir_item *di; u64 index; u64 ino = btrfs_ino(inode); u64 dir_ino = btrfs_ino(dir); path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } di = btrfs_lookup_dir_item(trans, root, path, dir_ino, name, -1); if (IS_ERR_OR_NULL(di)) { ret = di ? PTR_ERR(di) : -ENOENT; goto err; } ret = btrfs_delete_one_dir_name(trans, root, path, di); if (ret) goto err; btrfs_release_path(path); /* * If we don't have dir index, we have to get it by looking up * the inode ref, since we get the inode ref, remove it directly, * it is unnecessary to do delayed deletion. * * But if we have dir index, needn't search inode ref to get it. * Since the inode ref is close to the inode item, it is better * that we delay to delete it, and just do this deletion when * we update the inode item. */ if (inode->dir_index) { ret = btrfs_delayed_delete_inode_ref(inode); if (!ret) { index = inode->dir_index; goto skip_backref; } } ret = btrfs_del_inode_ref(trans, root, name, ino, dir_ino, &index); if (ret) { btrfs_info(fs_info, "failed to delete reference to %.*s, inode %llu parent %llu", name->len, name->name, ino, dir_ino); btrfs_abort_transaction(trans, ret); goto err; } skip_backref: if (rename_ctx) rename_ctx->index = index; ret = btrfs_delete_delayed_dir_index(trans, dir, index); if (ret) { btrfs_abort_transaction(trans, ret); goto err; } /* * If we are in a rename context, we don't need to update anything in the * log. That will be done later during the rename by btrfs_log_new_name(). * Besides that, doing it here would only cause extra unnecessary btree * operations on the log tree, increasing latency for applications. */ if (!rename_ctx) { btrfs_del_inode_ref_in_log(trans, root, name, inode, dir_ino); btrfs_del_dir_entries_in_log(trans, root, name, dir, index); } /* * If we have a pending delayed iput we could end up with the final iput * being run in btrfs-cleaner context. If we have enough of these built * up we can end up burning a lot of time in btrfs-cleaner without any * way to throttle the unlinks. Since we're currently holding a ref on * the inode we can run the delayed iput here without any issues as the * final iput won't be done until after we drop the ref we're currently * holding. */ btrfs_run_delayed_iput(fs_info, inode); err: btrfs_free_path(path); if (ret) goto out; btrfs_i_size_write(dir, dir->vfs_inode.i_size - name->len * 2); inode_inc_iversion(&inode->vfs_inode); inode_set_ctime_current(&inode->vfs_inode); inode_inc_iversion(&dir->vfs_inode); inode_set_mtime_to_ts(&dir->vfs_inode, inode_set_ctime_current(&dir->vfs_inode)); ret = btrfs_update_inode(trans, dir); out: return ret; } int btrfs_unlink_inode(struct btrfs_trans_handle *trans, struct btrfs_inode *dir, struct btrfs_inode *inode, const struct fscrypt_str *name) { int ret; ret = __btrfs_unlink_inode(trans, dir, inode, name, NULL); if (!ret) { drop_nlink(&inode->vfs_inode); ret = btrfs_update_inode(trans, inode); } return ret; } /* * helper to start transaction for unlink and rmdir. * * unlink and rmdir are special in btrfs, they do not always free space, so * if we cannot make our reservations the normal way try and see if there is * plenty of slack room in the global reserve to migrate, otherwise we cannot * allow the unlink to occur. */ static struct btrfs_trans_handle *__unlink_start_trans(struct btrfs_inode *dir) { struct btrfs_root *root = dir->root; return btrfs_start_transaction_fallback_global_rsv(root, BTRFS_UNLINK_METADATA_UNITS); } static int btrfs_unlink(struct inode *dir, struct dentry *dentry) { struct btrfs_trans_handle *trans; struct inode *inode = d_inode(dentry); int ret; struct fscrypt_name fname; ret = fscrypt_setup_filename(dir, &dentry->d_name, 1, &fname); if (ret) return ret; /* This needs to handle no-key deletions later on */ trans = __unlink_start_trans(BTRFS_I(dir)); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto fscrypt_free; } btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), false); ret = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), &fname.disk_name); if (ret) goto end_trans; if (inode->i_nlink == 0) { ret = btrfs_orphan_add(trans, BTRFS_I(inode)); if (ret) goto end_trans; } end_trans: btrfs_end_transaction(trans); btrfs_btree_balance_dirty(BTRFS_I(dir)->root->fs_info); fscrypt_free: fscrypt_free_filename(&fname); return ret; } static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, struct btrfs_inode *dir, struct dentry *dentry) { struct btrfs_root *root = dir->root; struct btrfs_inode *inode = BTRFS_I(d_inode(dentry)); struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_dir_item *di; struct btrfs_key key; u64 index; int ret; u64 objectid; u64 dir_ino = btrfs_ino(dir); struct fscrypt_name fname; ret = fscrypt_setup_filename(&dir->vfs_inode, &dentry->d_name, 1, &fname); if (ret) return ret; /* This needs to handle no-key deletions later on */ if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID) { objectid = btrfs_root_id(inode->root); } else if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) { objectid = inode->ref_root_id; } else { WARN_ON(1); fscrypt_free_filename(&fname); return -EINVAL; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } di = btrfs_lookup_dir_item(trans, root, path, dir_ino, &fname.disk_name, -1); if (IS_ERR_OR_NULL(di)) { ret = di ? PTR_ERR(di) : -ENOENT; goto out; } leaf = path->nodes[0]; btrfs_dir_item_key_to_cpu(leaf, di, &key); WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); ret = btrfs_delete_one_dir_name(trans, root, path, di); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } btrfs_release_path(path); /* * This is a placeholder inode for a subvolume we didn't have a * reference to at the time of the snapshot creation. In the meantime * we could have renamed the real subvol link into our snapshot, so * depending on btrfs_del_root_ref to return -ENOENT here is incorrect. * Instead simply lookup the dir_index_item for this entry so we can * remove it. Otherwise we know we have a ref to the root and we can * call btrfs_del_root_ref, and it _shouldn't_ fail. */ if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) { di = btrfs_search_dir_index_item(root, path, dir_ino, &fname.disk_name); if (IS_ERR(di)) { ret = PTR_ERR(di); btrfs_abort_transaction(trans, ret); goto out; } leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); index = key.offset; btrfs_release_path(path); } else { ret = btrfs_del_root_ref(trans, objectid, btrfs_root_id(root), dir_ino, &index, &fname.disk_name); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } } ret = btrfs_delete_delayed_dir_index(trans, dir, index); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } btrfs_i_size_write(dir, dir->vfs_inode.i_size - fname.disk_name.len * 2); inode_inc_iversion(&dir->vfs_inode); inode_set_mtime_to_ts(&dir->vfs_inode, inode_set_ctime_current(&dir->vfs_inode)); ret = btrfs_update_inode_fallback(trans, dir); if (ret) btrfs_abort_transaction(trans, ret); out: btrfs_free_path(path); fscrypt_free_filename(&fname); return ret; } /* * Helper to check if the subvolume references other subvolumes or if it's * default. */ static noinline int may_destroy_subvol(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_path *path; struct btrfs_dir_item *di; struct btrfs_key key; struct fscrypt_str name = FSTR_INIT("default", 7); u64 dir_id; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* Make sure this root isn't set as the default subvol */ dir_id = btrfs_super_root_dir(fs_info->super_copy); di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path, dir_id, &name, 0); if (di && !IS_ERR(di)) { btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key); if (key.objectid == btrfs_root_id(root)) { ret = -EPERM; btrfs_err(fs_info, "deleting default subvolume %llu is not allowed", key.objectid); goto out; } btrfs_release_path(path); } key.objectid = btrfs_root_id(root); key.type = BTRFS_ROOT_REF_KEY; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); if (ret < 0) goto out; if (ret == 0) { /* * Key with offset -1 found, there would have to exist a root * with such id, but this is out of valid range. */ ret = -EUCLEAN; goto out; } ret = 0; if (path->slots[0] > 0) { path->slots[0]--; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid == btrfs_root_id(root) && key.type == BTRFS_ROOT_REF_KEY) ret = -ENOTEMPTY; } out: btrfs_free_path(path); return ret; } /* Delete all dentries for inodes belonging to the root */ static void btrfs_prune_dentries(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_inode *inode; u64 min_ino = 0; if (!BTRFS_FS_ERROR(fs_info)) WARN_ON(btrfs_root_refs(&root->root_item) != 0); inode = btrfs_find_first_inode(root, min_ino); while (inode) { if (atomic_read(&inode->vfs_inode.i_count) > 1) d_prune_aliases(&inode->vfs_inode); min_ino = btrfs_ino(inode) + 1; /* * btrfs_drop_inode() will have it removed from the inode * cache when its usage count hits zero. */ iput(&inode->vfs_inode); cond_resched(); inode = btrfs_find_first_inode(root, min_ino); } } int btrfs_delete_subvolume(struct btrfs_inode *dir, struct dentry *dentry) { struct btrfs_root *root = dir->root; struct btrfs_fs_info *fs_info = root->fs_info; struct inode *inode = d_inode(dentry); struct btrfs_root *dest = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; struct btrfs_block_rsv block_rsv; u64 root_flags; u64 qgroup_reserved = 0; int ret; down_write(&fs_info->subvol_sem); /* * Don't allow to delete a subvolume with send in progress. This is * inside the inode lock so the error handling that has to drop the bit * again is not run concurrently. */ spin_lock(&dest->root_item_lock); if (dest->send_in_progress) { spin_unlock(&dest->root_item_lock); btrfs_warn(fs_info, "attempt to delete subvolume %llu during send", btrfs_root_id(dest)); ret = -EPERM; goto out_up_write; } if (atomic_read(&dest->nr_swapfiles)) { spin_unlock(&dest->root_item_lock); btrfs_warn(fs_info, "attempt to delete subvolume %llu with active swapfile", btrfs_root_id(root)); ret = -EPERM; goto out_up_write; } root_flags = btrfs_root_flags(&dest->root_item); btrfs_set_root_flags(&dest->root_item, root_flags | BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); ret = may_destroy_subvol(dest); if (ret) goto out_undead; btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); /* * One for dir inode, * two for dir entries, * two for root ref/backref. */ ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true); if (ret) goto out_undead; qgroup_reserved = block_rsv.qgroup_rsv_reserved; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_release; } btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); qgroup_reserved = 0; trans->block_rsv = &block_rsv; trans->bytes_reserved = block_rsv.size; btrfs_record_snapshot_destroy(trans, dir); ret = btrfs_unlink_subvol(trans, dir, dentry); if (ret) { btrfs_abort_transaction(trans, ret); goto out_end_trans; } ret = btrfs_record_root_in_trans(trans, dest); if (ret) { btrfs_abort_transaction(trans, ret); goto out_end_trans; } memset(&dest->root_item.drop_progress, 0, sizeof(dest->root_item.drop_progress)); btrfs_set_root_drop_level(&dest->root_item, 0); btrfs_set_root_refs(&dest->root_item, 0); if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) { ret = btrfs_insert_orphan_item(trans, fs_info->tree_root, btrfs_root_id(dest)); if (ret) { btrfs_abort_transaction(trans, ret); goto out_end_trans; } } ret = btrfs_uuid_tree_remove(trans, dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL, btrfs_root_id(dest)); if (ret && ret != -ENOENT) { btrfs_abort_transaction(trans, ret); goto out_end_trans; } if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) { ret = btrfs_uuid_tree_remove(trans, dest->root_item.received_uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, btrfs_root_id(dest)); if (ret && ret != -ENOENT) { btrfs_abort_transaction(trans, ret); goto out_end_trans; } } free_anon_bdev(dest->anon_dev); dest->anon_dev = 0; out_end_trans: trans->block_rsv = NULL; trans->bytes_reserved = 0; ret = btrfs_end_transaction(trans); inode->i_flags |= S_DEAD; out_release: btrfs_block_rsv_release(fs_info, &block_rsv, (u64)-1, NULL); if (qgroup_reserved) btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved); out_undead: if (ret) { spin_lock(&dest->root_item_lock); root_flags = btrfs_root_flags(&dest->root_item); btrfs_set_root_flags(&dest->root_item, root_flags & ~BTRFS_ROOT_SUBVOL_DEAD); spin_unlock(&dest->root_item_lock); } out_up_write: up_write(&fs_info->subvol_sem); if (!ret) { d_invalidate(dentry); btrfs_prune_dentries(dest); ASSERT(dest->send_in_progress == 0); } return ret; } static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) { struct inode *inode = d_inode(dentry); struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; int ret = 0; struct btrfs_trans_handle *trans; u64 last_unlink_trans; struct fscrypt_name fname; if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) return -ENOTEMPTY; if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID) { if (unlikely(btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))) { btrfs_err(fs_info, "extent tree v2 doesn't support snapshot deletion yet"); return -EOPNOTSUPP; } return btrfs_delete_subvolume(BTRFS_I(dir), dentry); } ret = fscrypt_setup_filename(dir, &dentry->d_name, 1, &fname); if (ret) return ret; /* This needs to handle no-key deletions later on */ trans = __unlink_start_trans(BTRFS_I(dir)); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_notrans; } if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { ret = btrfs_unlink_subvol(trans, BTRFS_I(dir), dentry); goto out; } ret = btrfs_orphan_add(trans, BTRFS_I(inode)); if (ret) goto out; last_unlink_trans = BTRFS_I(inode)->last_unlink_trans; /* now the directory is empty */ ret = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)), &fname.disk_name); if (!ret) { btrfs_i_size_write(BTRFS_I(inode), 0); /* * Propagate the last_unlink_trans value of the deleted dir to * its parent directory. This is to prevent an unrecoverable * log tree in the case we do something like this: * 1) create dir foo * 2) create snapshot under dir foo * 3) delete the snapshot * 4) rmdir foo * 5) mkdir foo * 6) fsync foo or some file inside foo */ if (last_unlink_trans >= trans->transid) BTRFS_I(dir)->last_unlink_trans = last_unlink_trans; } out: btrfs_end_transaction(trans); out_notrans: btrfs_btree_balance_dirty(fs_info); fscrypt_free_filename(&fname); return ret; } /* * Read, zero a chunk and write a block. * * @inode - inode that we're zeroing * @from - the offset to start zeroing * @len - the length to zero, 0 to zero the entire range respective to the * offset * @front - zero up to the offset instead of from the offset on * * This will find the block for the "from" offset and cow the block and zero the * part we want to zero. This is used with truncate and hole punching. */ int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len, int front) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct address_space *mapping = inode->vfs_inode.i_mapping; struct extent_io_tree *io_tree = &inode->io_tree; struct btrfs_ordered_extent *ordered; struct extent_state *cached_state = NULL; struct extent_changeset *data_reserved = NULL; bool only_release_metadata = false; u32 blocksize = fs_info->sectorsize; pgoff_t index = from >> PAGE_SHIFT; unsigned offset = from & (blocksize - 1); struct folio *folio; gfp_t mask = btrfs_alloc_write_mask(mapping); size_t write_bytes = blocksize; int ret = 0; u64 block_start; u64 block_end; if (IS_ALIGNED(offset, blocksize) && (!len || IS_ALIGNED(len, blocksize))) goto out; block_start = round_down(from, blocksize); block_end = block_start + blocksize - 1; ret = btrfs_check_data_free_space(inode, &data_reserved, block_start, blocksize, false); if (ret < 0) { if (btrfs_check_nocow_lock(inode, block_start, &write_bytes, false) > 0) { /* For nocow case, no need to reserve data space */ only_release_metadata = true; } else { goto out; } } ret = btrfs_delalloc_reserve_metadata(inode, blocksize, blocksize, false); if (ret < 0) { if (!only_release_metadata) btrfs_free_reserved_data_space(inode, data_reserved, block_start, blocksize); goto out; } again: folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_ACCESSED | FGP_CREAT, mask); if (IS_ERR(folio)) { btrfs_delalloc_release_space(inode, data_reserved, block_start, blocksize, true); btrfs_delalloc_release_extents(inode, blocksize); ret = -ENOMEM; goto out; } if (!folio_test_uptodate(folio)) { ret = btrfs_read_folio(NULL, folio); folio_lock(folio); if (folio->mapping != mapping) { folio_unlock(folio); folio_put(folio); goto again; } if (!folio_test_uptodate(folio)) { ret = -EIO; goto out_unlock; } } /* * We unlock the page after the io is completed and then re-lock it * above. release_folio() could have come in between that and cleared * folio private, but left the page in the mapping. Set the page mapped * here to make sure it's properly set for the subpage stuff. */ ret = set_folio_extent_mapped(folio); if (ret < 0) goto out_unlock; folio_wait_writeback(folio); lock_extent(io_tree, block_start, block_end, &cached_state); ordered = btrfs_lookup_ordered_extent(inode, block_start); if (ordered) { unlock_extent(io_tree, block_start, block_end, &cached_state); folio_unlock(folio); folio_put(folio); btrfs_start_ordered_extent(ordered); btrfs_put_ordered_extent(ordered); goto again; } clear_extent_bit(&inode->io_tree, block_start, block_end, EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, &cached_state); ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 0, &cached_state); if (ret) { unlock_extent(io_tree, block_start, block_end, &cached_state); goto out_unlock; } if (offset != blocksize) { if (!len) len = blocksize - offset; if (front) folio_zero_range(folio, block_start - folio_pos(folio), offset); else folio_zero_range(folio, (block_start - folio_pos(folio)) + offset, len); } btrfs_folio_clear_checked(fs_info, folio, block_start, block_end + 1 - block_start); btrfs_folio_set_dirty(fs_info, folio, block_start, block_end + 1 - block_start); unlock_extent(io_tree, block_start, block_end, &cached_state); if (only_release_metadata) set_extent_bit(&inode->io_tree, block_start, block_end, EXTENT_NORESERVE, NULL); out_unlock: if (ret) { if (only_release_metadata) btrfs_delalloc_release_metadata(inode, blocksize, true); else btrfs_delalloc_release_space(inode, data_reserved, block_start, blocksize, true); } btrfs_delalloc_release_extents(inode, blocksize); folio_unlock(folio); folio_put(folio); out: if (only_release_metadata) btrfs_check_nocow_unlock(inode); extent_changeset_free(data_reserved); return ret; } static int maybe_insert_hole(struct btrfs_inode *inode, u64 offset, u64 len) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans; struct btrfs_drop_extents_args drop_args = { 0 }; int ret; /* * If NO_HOLES is enabled, we don't need to do anything. * Later, up in the call chain, either btrfs_set_inode_last_sub_trans() * or btrfs_update_inode() will be called, which guarantee that the next * fsync will know this inode was changed and needs to be logged. */ if (btrfs_fs_incompat(fs_info, NO_HOLES)) return 0; /* * 1 - for the one we're dropping * 1 - for the one we're adding * 1 - for updating the inode. */ trans = btrfs_start_transaction(root, 3); if (IS_ERR(trans)) return PTR_ERR(trans); drop_args.start = offset; drop_args.end = offset + len; drop_args.drop_cache = true; ret = btrfs_drop_extents(trans, root, inode, &drop_args); if (ret) { btrfs_abort_transaction(trans, ret); btrfs_end_transaction(trans); return ret; } ret = btrfs_insert_hole_extent(trans, root, btrfs_ino(inode), offset, len); if (ret) { btrfs_abort_transaction(trans, ret); } else { btrfs_update_inode_bytes(inode, 0, drop_args.bytes_found); btrfs_update_inode(trans, inode); } btrfs_end_transaction(trans); return ret; } /* * This function puts in dummy file extents for the area we're creating a hole * for. So if we are truncating this file to a larger size we need to insert * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for * the range between oldsize and size */ int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct extent_io_tree *io_tree = &inode->io_tree; struct extent_map *em = NULL; struct extent_state *cached_state = NULL; u64 hole_start = ALIGN(oldsize, fs_info->sectorsize); u64 block_end = ALIGN(size, fs_info->sectorsize); u64 last_byte; u64 cur_offset; u64 hole_size; int ret = 0; /* * If our size started in the middle of a block we need to zero out the * rest of the block before we expand the i_size, otherwise we could * expose stale data. */ ret = btrfs_truncate_block(inode, oldsize, 0, 0); if (ret) return ret; if (size <= hole_start) return 0; btrfs_lock_and_flush_ordered_range(inode, hole_start, block_end - 1, &cached_state); cur_offset = hole_start; while (1) { em = btrfs_get_extent(inode, NULL, cur_offset, block_end - cur_offset); if (IS_ERR(em)) { ret = PTR_ERR(em); em = NULL; break; } last_byte = min(extent_map_end(em), block_end); last_byte = ALIGN(last_byte, fs_info->sectorsize); hole_size = last_byte - cur_offset; if (!(em->flags & EXTENT_FLAG_PREALLOC)) { struct extent_map *hole_em; ret = maybe_insert_hole(inode, cur_offset, hole_size); if (ret) break; ret = btrfs_inode_set_file_extent_range(inode, cur_offset, hole_size); if (ret) break; hole_em = alloc_extent_map(); if (!hole_em) { btrfs_drop_extent_map_range(inode, cur_offset, cur_offset + hole_size - 1, false); btrfs_set_inode_full_sync(inode); goto next; } hole_em->start = cur_offset; hole_em->len = hole_size; hole_em->disk_bytenr = EXTENT_MAP_HOLE; hole_em->disk_num_bytes = 0; hole_em->ram_bytes = hole_size; hole_em->generation = btrfs_get_fs_generation(fs_info); ret = btrfs_replace_extent_map_range(inode, hole_em, true); free_extent_map(hole_em); } else { ret = btrfs_inode_set_file_extent_range(inode, cur_offset, hole_size); if (ret) break; } next: free_extent_map(em); em = NULL; cur_offset = last_byte; if (cur_offset >= block_end) break; } free_extent_map(em); unlock_extent(io_tree, hole_start, block_end - 1, &cached_state); return ret; } static int btrfs_setsize(struct inode *inode, struct iattr *attr) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; loff_t oldsize = i_size_read(inode); loff_t newsize = attr->ia_size; int mask = attr->ia_valid; int ret; /* * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a * special case where we need to update the times despite not having * these flags set. For all other operations the VFS set these flags * explicitly if it wants a timestamp update. */ if (newsize != oldsize) { inode_inc_iversion(inode); if (!(mask & (ATTR_CTIME | ATTR_MTIME))) { inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); } } if (newsize > oldsize) { /* * Don't do an expanding truncate while snapshotting is ongoing. * This is to ensure the snapshot captures a fully consistent * state of this file - if the snapshot captures this expanding * truncation, it must capture all writes that happened before * this truncation. */ btrfs_drew_write_lock(&root->snapshot_lock); ret = btrfs_cont_expand(BTRFS_I(inode), oldsize, newsize); if (ret) { btrfs_drew_write_unlock(&root->snapshot_lock); return ret; } trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { btrfs_drew_write_unlock(&root->snapshot_lock); return PTR_ERR(trans); } i_size_write(inode, newsize); btrfs_inode_safe_disk_i_size_write(BTRFS_I(inode), 0); pagecache_isize_extended(inode, oldsize, newsize); ret = btrfs_update_inode(trans, BTRFS_I(inode)); btrfs_drew_write_unlock(&root->snapshot_lock); btrfs_end_transaction(trans); } else { struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); if (btrfs_is_zoned(fs_info)) { ret = btrfs_wait_ordered_range(BTRFS_I(inode), ALIGN(newsize, fs_info->sectorsize), (u64)-1); if (ret) return ret; } /* * We're truncating a file that used to have good data down to * zero. Make sure any new writes to the file get on disk * on close. */ if (newsize == 0) set_bit(BTRFS_INODE_FLUSH_ON_CLOSE, &BTRFS_I(inode)->runtime_flags); truncate_setsize(inode, newsize); inode_dio_wait(inode); ret = btrfs_truncate(BTRFS_I(inode), newsize == oldsize); if (ret && inode->i_nlink) { int err; /* * Truncate failed, so fix up the in-memory size. We * adjusted disk_i_size down as we removed extents, so * wait for disk_i_size to be stable and then update the * in-memory size to match. */ err = btrfs_wait_ordered_range(BTRFS_I(inode), 0, (u64)-1); if (err) return err; i_size_write(inode, BTRFS_I(inode)->disk_i_size); } } return ret; } static int btrfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr) { struct inode *inode = d_inode(dentry); struct btrfs_root *root = BTRFS_I(inode)->root; int err; if (btrfs_root_readonly(root)) return -EROFS; err = setattr_prepare(idmap, dentry, attr); if (err) return err; if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { err = btrfs_setsize(inode, attr); if (err) return err; } if (attr->ia_valid) { setattr_copy(idmap, inode, attr); inode_inc_iversion(inode); err = btrfs_dirty_inode(BTRFS_I(inode)); if (!err && attr->ia_valid & ATTR_MODE) err = posix_acl_chmod(idmap, dentry, inode->i_mode); } return err; } /* * While truncating the inode pages during eviction, we get the VFS * calling btrfs_invalidate_folio() against each folio of the inode. This * is slow because the calls to btrfs_invalidate_folio() result in a * huge amount of calls to lock_extent() and clear_extent_bit(), * which keep merging and splitting extent_state structures over and over, * wasting lots of time. * * Therefore if the inode is being evicted, let btrfs_invalidate_folio() * skip all those expensive operations on a per folio basis and do only * the ordered io finishing, while we release here the extent_map and * extent_state structures, without the excessive merging and splitting. */ static void evict_inode_truncate_pages(struct inode *inode) { struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct rb_node *node; ASSERT(inode->i_state & I_FREEING); truncate_inode_pages_final(&inode->i_data); btrfs_drop_extent_map_range(BTRFS_I(inode), 0, (u64)-1, false); /* * Keep looping until we have no more ranges in the io tree. * We can have ongoing bios started by readahead that have * their endio callback (extent_io.c:end_bio_extent_readpage) * still in progress (unlocked the pages in the bio but did not yet * unlocked the ranges in the io tree). Therefore this means some * ranges can still be locked and eviction started because before * submitting those bios, which are executed by a separate task (work * queue kthread), inode references (inode->i_count) were not taken * (which would be dropped in the end io callback of each bio). * Therefore here we effectively end up waiting for those bios and * anyone else holding locked ranges without having bumped the inode's * reference count - if we don't do it, when they access the inode's * io_tree to unlock a range it may be too late, leading to an * use-after-free issue. */ spin_lock(&io_tree->lock); while (!RB_EMPTY_ROOT(&io_tree->state)) { struct extent_state *state; struct extent_state *cached_state = NULL; u64 start; u64 end; unsigned state_flags; node = rb_first(&io_tree->state); state = rb_entry(node, struct extent_state, rb_node); start = state->start; end = state->end; state_flags = state->state; spin_unlock(&io_tree->lock); lock_extent(io_tree, start, end, &cached_state); /* * If still has DELALLOC flag, the extent didn't reach disk, * and its reserved space won't be freed by delayed_ref. * So we need to free its reserved space here. * (Refer to comment in btrfs_invalidate_folio, case 2) * * Note, end is the bytenr of last byte, so we need + 1 here. */ if (state_flags & EXTENT_DELALLOC) btrfs_qgroup_free_data(BTRFS_I(inode), NULL, start, end - start + 1, NULL); clear_extent_bit(io_tree, start, end, EXTENT_CLEAR_ALL_BITS | EXTENT_DO_ACCOUNTING, &cached_state); cond_resched(); spin_lock(&io_tree->lock); } spin_unlock(&io_tree->lock); } static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root, struct btrfs_block_rsv *rsv) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans; u64 delayed_refs_extra = btrfs_calc_delayed_ref_bytes(fs_info, 1); int ret; /* * Eviction should be taking place at some place safe because of our * delayed iputs. However the normal flushing code will run delayed * iputs, so we cannot use FLUSH_ALL otherwise we'll deadlock. * * We reserve the delayed_refs_extra here again because we can't use * btrfs_start_transaction(root, 0) for the same deadlocky reason as * above. We reserve our extra bit here because we generate a ton of * delayed refs activity by truncating. * * BTRFS_RESERVE_FLUSH_EVICT will steal from the global_rsv if it can, * if we fail to make this reservation we can re-try without the * delayed_refs_extra so we can make some forward progress. */ ret = btrfs_block_rsv_refill(fs_info, rsv, rsv->size + delayed_refs_extra, BTRFS_RESERVE_FLUSH_EVICT); if (ret) { ret = btrfs_block_rsv_refill(fs_info, rsv, rsv->size, BTRFS_RESERVE_FLUSH_EVICT); if (ret) { btrfs_warn(fs_info, "could not allocate space for delete; will truncate on mount"); return ERR_PTR(-ENOSPC); } delayed_refs_extra = 0; } trans = btrfs_join_transaction(root); if (IS_ERR(trans)) return trans; if (delayed_refs_extra) { trans->block_rsv = &fs_info->trans_block_rsv; trans->bytes_reserved = delayed_refs_extra; btrfs_block_rsv_migrate(rsv, trans->block_rsv, delayed_refs_extra, true); } return trans; } void btrfs_evict_inode(struct inode *inode) { struct btrfs_fs_info *fs_info; struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_block_rsv *rsv = NULL; int ret; trace_btrfs_inode_evict(inode); if (!root) { fsverity_cleanup_inode(inode); clear_inode(inode); return; } fs_info = inode_to_fs_info(inode); evict_inode_truncate_pages(inode); if (inode->i_nlink && ((btrfs_root_refs(&root->root_item) != 0 && btrfs_root_id(root) != BTRFS_ROOT_TREE_OBJECTID) || btrfs_is_free_space_inode(BTRFS_I(inode)))) goto out; if (is_bad_inode(inode)) goto out; if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) goto out; if (inode->i_nlink > 0) { BUG_ON(btrfs_root_refs(&root->root_item) != 0 && btrfs_root_id(root) != BTRFS_ROOT_TREE_OBJECTID); goto out; } /* * This makes sure the inode item in tree is uptodate and the space for * the inode update is released. */ ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode)); if (ret) goto out; /* * This drops any pending insert or delete operations we have for this * inode. We could have a delayed dir index deletion queued up, but * we're removing the inode completely so that'll be taken care of in * the truncate. */ btrfs_kill_delayed_inode_items(BTRFS_I(inode)); rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); if (!rsv) goto out; rsv->size = btrfs_calc_metadata_size(fs_info, 1); rsv->failfast = true; btrfs_i_size_write(BTRFS_I(inode), 0); while (1) { struct btrfs_truncate_control control = { .inode = BTRFS_I(inode), .ino = btrfs_ino(BTRFS_I(inode)), .new_size = 0, .min_type = 0, }; trans = evict_refill_and_join(root, rsv); if (IS_ERR(trans)) goto out; trans->block_rsv = rsv; ret = btrfs_truncate_inode_items(trans, root, &control); trans->block_rsv = &fs_info->trans_block_rsv; btrfs_end_transaction(trans); /* * We have not added new delayed items for our inode after we * have flushed its delayed items, so no need to throttle on * delayed items. However we have modified extent buffers. */ btrfs_btree_balance_dirty_nodelay(fs_info); if (ret && ret != -ENOSPC && ret != -EAGAIN) goto out; else if (!ret) break; } /* * Errors here aren't a big deal, it just means we leave orphan items in * the tree. They will be cleaned up on the next mount. If the inode * number gets reused, cleanup deletes the orphan item without doing * anything, and unlink reuses the existing orphan item. * * If it turns out that we are dropping too many of these, we might want * to add a mechanism for retrying these after a commit. */ trans = evict_refill_and_join(root, rsv); if (!IS_ERR(trans)) { trans->block_rsv = rsv; btrfs_orphan_del(trans, BTRFS_I(inode)); trans->block_rsv = &fs_info->trans_block_rsv; btrfs_end_transaction(trans); } out: btrfs_free_block_rsv(fs_info, rsv); /* * If we didn't successfully delete, the orphan item will still be in * the tree and we'll retry on the next mount. Again, we might also want * to retry these periodically in the future. */ btrfs_remove_delayed_node(BTRFS_I(inode)); fsverity_cleanup_inode(inode); clear_inode(inode); } /* * Return the key found in the dir entry in the location pointer, fill @type * with BTRFS_FT_*, and return 0. * * If no dir entries were found, returns -ENOENT. * If found a corrupted location in dir entry, returns -EUCLEAN. */ static int btrfs_inode_by_name(struct btrfs_inode *dir, struct dentry *dentry, struct btrfs_key *location, u8 *type) { struct btrfs_dir_item *di; struct btrfs_path *path; struct btrfs_root *root = dir->root; int ret = 0; struct fscrypt_name fname; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = fscrypt_setup_filename(&dir->vfs_inode, &dentry->d_name, 1, &fname); if (ret < 0) goto out; /* * fscrypt_setup_filename() should never return a positive value, but * gcc on sparc/parisc thinks it can, so assert that doesn't happen. */ ASSERT(ret == 0); /* This needs to handle no-key deletions later on */ di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), &fname.disk_name, 0); if (IS_ERR_OR_NULL(di)) { ret = di ? PTR_ERR(di) : -ENOENT; goto out; } btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); if (location->type != BTRFS_INODE_ITEM_KEY && location->type != BTRFS_ROOT_ITEM_KEY) { ret = -EUCLEAN; btrfs_warn(root->fs_info, "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))", __func__, fname.disk_name.name, btrfs_ino(dir), location->objectid, location->type, location->offset); } if (!ret) *type = btrfs_dir_ftype(path->nodes[0], di); out: fscrypt_free_filename(&fname); btrfs_free_path(path); return ret; } /* * when we hit a tree root in a directory, the btrfs part of the inode * needs to be changed to reflect the root directory of the tree root. This * is kind of like crossing a mount point. */ static int fixup_tree_root_location(struct btrfs_fs_info *fs_info, struct btrfs_inode *dir, struct dentry *dentry, struct btrfs_key *location, struct btrfs_root **sub_root) { struct btrfs_path *path; struct btrfs_root *new_root; struct btrfs_root_ref *ref; struct extent_buffer *leaf; struct btrfs_key key; int ret; int err = 0; struct fscrypt_name fname; ret = fscrypt_setup_filename(&dir->vfs_inode, &dentry->d_name, 0, &fname); if (ret) return ret; path = btrfs_alloc_path(); if (!path) { err = -ENOMEM; goto out; } err = -ENOENT; key.objectid = btrfs_root_id(dir->root); key.type = BTRFS_ROOT_REF_KEY; key.offset = location->objectid; ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); if (ret) { if (ret < 0) err = ret; goto out; } leaf = path->nodes[0]; ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) || btrfs_root_ref_name_len(leaf, ref) != fname.disk_name.len) goto out; ret = memcmp_extent_buffer(leaf, fname.disk_name.name, (unsigned long)(ref + 1), fname.disk_name.len); if (ret) goto out; btrfs_release_path(path); new_root = btrfs_get_fs_root(fs_info, location->objectid, true); if (IS_ERR(new_root)) { err = PTR_ERR(new_root); goto out; } *sub_root = new_root; location->objectid = btrfs_root_dirid(&new_root->root_item); location->type = BTRFS_INODE_ITEM_KEY; location->offset = 0; err = 0; out: btrfs_free_path(path); fscrypt_free_filename(&fname); return err; } static int btrfs_add_inode_to_root(struct btrfs_inode *inode, bool prealloc) { struct btrfs_root *root = inode->root; struct btrfs_inode *existing; const u64 ino = btrfs_ino(inode); int ret; if (inode_unhashed(&inode->vfs_inode)) return 0; if (prealloc) { ret = xa_reserve(&root->inodes, ino, GFP_NOFS); if (ret) return ret; } existing = xa_store(&root->inodes, ino, inode, GFP_ATOMIC); if (xa_is_err(existing)) { ret = xa_err(existing); ASSERT(ret != -EINVAL); ASSERT(ret != -ENOMEM); return ret; } else if (existing) { WARN_ON(!(existing->vfs_inode.i_state & (I_WILL_FREE | I_FREEING))); } return 0; } static void btrfs_del_inode_from_root(struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_inode *entry; bool empty = false; xa_lock(&root->inodes); entry = __xa_erase(&root->inodes, btrfs_ino(inode)); if (entry == inode) empty = xa_empty(&root->inodes); xa_unlock(&root->inodes); if (empty && btrfs_root_refs(&root->root_item) == 0) { xa_lock(&root->inodes); empty = xa_empty(&root->inodes); xa_unlock(&root->inodes); if (empty) btrfs_add_dead_root(root); } } static int btrfs_init_locked_inode(struct inode *inode, void *p) { struct btrfs_iget_args *args = p; btrfs_set_inode_number(BTRFS_I(inode), args->ino); BTRFS_I(inode)->root = btrfs_grab_root(args->root); if (args->root && args->root == args->root->fs_info->tree_root && args->ino != BTRFS_BTREE_INODE_OBJECTID) set_bit(BTRFS_INODE_FREE_SPACE_INODE, &BTRFS_I(inode)->runtime_flags); return 0; } static int btrfs_find_actor(struct inode *inode, void *opaque) { struct btrfs_iget_args *args = opaque; return args->ino == btrfs_ino(BTRFS_I(inode)) && args->root == BTRFS_I(inode)->root; } static struct inode *btrfs_iget_locked(u64 ino, struct btrfs_root *root) { struct inode *inode; struct btrfs_iget_args args; unsigned long hashval = btrfs_inode_hash(ino, root); args.ino = ino; args.root = root; inode = iget5_locked_rcu(root->fs_info->sb, hashval, btrfs_find_actor, btrfs_init_locked_inode, (void *)&args); return inode; } /* * Get an inode object given its inode number and corresponding root. * Path can be preallocated to prevent recursing back to iget through * allocator. NULL is also valid but may require an additional allocation * later. */ struct inode *btrfs_iget_path(u64 ino, struct btrfs_root *root, struct btrfs_path *path) { struct inode *inode; int ret; inode = btrfs_iget_locked(ino, root); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) return inode; ret = btrfs_read_locked_inode(inode, path); /* * ret > 0 can come from btrfs_search_slot called by * btrfs_read_locked_inode(), this means the inode item was not found. */ if (ret > 0) ret = -ENOENT; if (ret < 0) goto error; ret = btrfs_add_inode_to_root(BTRFS_I(inode), true); if (ret < 0) goto error; unlock_new_inode(inode); return inode; error: iget_failed(inode); return ERR_PTR(ret); } struct inode *btrfs_iget(u64 ino, struct btrfs_root *root) { return btrfs_iget_path(ino, root, NULL); } static struct inode *new_simple_dir(struct inode *dir, struct btrfs_key *key, struct btrfs_root *root) { struct timespec64 ts; struct inode *inode = new_inode(dir->i_sb); if (!inode) return ERR_PTR(-ENOMEM); BTRFS_I(inode)->root = btrfs_grab_root(root); BTRFS_I(inode)->ref_root_id = key->objectid; set_bit(BTRFS_INODE_ROOT_STUB, &BTRFS_I(inode)->runtime_flags); set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags); btrfs_set_inode_number(BTRFS_I(inode), BTRFS_EMPTY_SUBVOL_DIR_OBJECTID); /* * We only need lookup, the rest is read-only and there's no inode * associated with the dentry */ inode->i_op = &simple_dir_inode_operations; inode->i_opflags &= ~IOP_XATTR; inode->i_fop = &simple_dir_operations; inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; ts = inode_set_ctime_current(inode); inode_set_mtime_to_ts(inode, ts); inode_set_atime_to_ts(inode, inode_get_atime(dir)); BTRFS_I(inode)->i_otime_sec = ts.tv_sec; BTRFS_I(inode)->i_otime_nsec = ts.tv_nsec; inode->i_uid = dir->i_uid; inode->i_gid = dir->i_gid; return inode; } static_assert(BTRFS_FT_UNKNOWN == FT_UNKNOWN); static_assert(BTRFS_FT_REG_FILE == FT_REG_FILE); static_assert(BTRFS_FT_DIR == FT_DIR); static_assert(BTRFS_FT_CHRDEV == FT_CHRDEV); static_assert(BTRFS_FT_BLKDEV == FT_BLKDEV); static_assert(BTRFS_FT_FIFO == FT_FIFO); static_assert(BTRFS_FT_SOCK == FT_SOCK); static_assert(BTRFS_FT_SYMLINK == FT_SYMLINK); static inline u8 btrfs_inode_type(struct inode *inode) { return fs_umode_to_ftype(inode->i_mode); } struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) { struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); struct inode *inode; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_root *sub_root = root; struct btrfs_key location = { 0 }; u8 di_type = 0; int ret = 0; if (dentry->d_name.len > BTRFS_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); ret = btrfs_inode_by_name(BTRFS_I(dir), dentry, &location, &di_type); if (ret < 0) return ERR_PTR(ret); if (location.type == BTRFS_INODE_ITEM_KEY) { inode = btrfs_iget(location.objectid, root); if (IS_ERR(inode)) return inode; /* Do extra check against inode mode with di_type */ if (btrfs_inode_type(inode) != di_type) { btrfs_crit(fs_info, "inode mode mismatch with dir: inode mode=0%o btrfs type=%u dir type=%u", inode->i_mode, btrfs_inode_type(inode), di_type); iput(inode); return ERR_PTR(-EUCLEAN); } return inode; } ret = fixup_tree_root_location(fs_info, BTRFS_I(dir), dentry, &location, &sub_root); if (ret < 0) { if (ret != -ENOENT) inode = ERR_PTR(ret); else inode = new_simple_dir(dir, &location, root); } else { inode = btrfs_iget(location.objectid, sub_root); btrfs_put_root(sub_root); if (IS_ERR(inode)) return inode; down_read(&fs_info->cleanup_work_sem); if (!sb_rdonly(inode->i_sb)) ret = btrfs_orphan_cleanup(sub_root); up_read(&fs_info->cleanup_work_sem); if (ret) { iput(inode); inode = ERR_PTR(ret); } } return inode; } static int btrfs_dentry_delete(const struct dentry *dentry) { struct btrfs_root *root; struct inode *inode = d_inode(dentry); if (!inode && !IS_ROOT(dentry)) inode = d_inode(dentry->d_parent); if (inode) { root = BTRFS_I(inode)->root; if (btrfs_root_refs(&root->root_item) == 0) return 1; if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) return 1; } return 0; } static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { struct inode *inode = btrfs_lookup_dentry(dir, dentry); if (inode == ERR_PTR(-ENOENT)) inode = NULL; return d_splice_alias(inode, dentry); } /* * Find the highest existing sequence number in a directory and then set the * in-memory index_cnt variable to the first free sequence number. */ static int btrfs_set_inode_index_count(struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_key key, found_key; struct btrfs_path *path; struct extent_buffer *leaf; int ret; key.objectid = btrfs_ino(inode); key.type = BTRFS_DIR_INDEX_KEY; key.offset = (u64)-1; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; /* FIXME: we should be able to handle this */ if (ret == 0) goto out; ret = 0; if (path->slots[0] == 0) { inode->index_cnt = BTRFS_DIR_START_INDEX; goto out; } path->slots[0]--; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid != btrfs_ino(inode) || found_key.type != BTRFS_DIR_INDEX_KEY) { inode->index_cnt = BTRFS_DIR_START_INDEX; goto out; } inode->index_cnt = found_key.offset + 1; out: btrfs_free_path(path); return ret; } static int btrfs_get_dir_last_index(struct btrfs_inode *dir, u64 *index) { int ret = 0; btrfs_inode_lock(dir, 0); if (dir->index_cnt == (u64)-1) { ret = btrfs_inode_delayed_dir_index_count(dir); if (ret) { ret = btrfs_set_inode_index_count(dir); if (ret) goto out; } } /* index_cnt is the index number of next new entry, so decrement it. */ *index = dir->index_cnt - 1; out: btrfs_inode_unlock(dir, 0); return ret; } /* * All this infrastructure exists because dir_emit can fault, and we are holding * the tree lock when doing readdir. For now just allocate a buffer and copy * our information into that, and then dir_emit from the buffer. This is * similar to what NFS does, only we don't keep the buffer around in pagecache * because I'm afraid I'll mess that up. Long term we need to make filldir do * copy_to_user_inatomic so we don't have to worry about page faulting under the * tree lock. */ static int btrfs_opendir(struct inode *inode, struct file *file) { struct btrfs_file_private *private; u64 last_index; int ret; ret = btrfs_get_dir_last_index(BTRFS_I(inode), &last_index); if (ret) return ret; private = kzalloc(sizeof(struct btrfs_file_private), GFP_KERNEL); if (!private) return -ENOMEM; private->last_index = last_index; private->filldir_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); if (!private->filldir_buf) { kfree(private); return -ENOMEM; } file->private_data = private; return 0; } static loff_t btrfs_dir_llseek(struct file *file, loff_t offset, int whence) { struct btrfs_file_private *private = file->private_data; int ret; ret = btrfs_get_dir_last_index(BTRFS_I(file_inode(file)), &private->last_index); if (ret) return ret; return generic_file_llseek(file, offset, whence); } struct dir_entry { u64 ino; u64 offset; unsigned type; int name_len; }; static int btrfs_filldir(void *addr, int entries, struct dir_context *ctx) { while (entries--) { struct dir_entry *entry = addr; char *name = (char *)(entry + 1); ctx->pos = get_unaligned(&entry->offset); if (!dir_emit(ctx, name, get_unaligned(&entry->name_len), get_unaligned(&entry->ino), get_unaligned(&entry->type))) return 1; addr += sizeof(struct dir_entry) + get_unaligned(&entry->name_len); ctx->pos++; } return 0; } static int btrfs_real_readdir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_file_private *private = file->private_data; struct btrfs_dir_item *di; struct btrfs_key key; struct btrfs_key found_key; struct btrfs_path *path; void *addr; LIST_HEAD(ins_list); LIST_HEAD(del_list); int ret; char *name_ptr; int name_len; int entries = 0; int total_len = 0; bool put = false; struct btrfs_key location; if (!dir_emit_dots(file, ctx)) return 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; addr = private->filldir_buf; path->reada = READA_FORWARD; put = btrfs_readdir_get_delayed_items(BTRFS_I(inode), private->last_index, &ins_list, &del_list); again: key.type = BTRFS_DIR_INDEX_KEY; key.offset = ctx->pos; key.objectid = btrfs_ino(BTRFS_I(inode)); btrfs_for_each_slot(root, &key, &found_key, path, ret) { struct dir_entry *entry; struct extent_buffer *leaf = path->nodes[0]; u8 ftype; if (found_key.objectid != key.objectid) break; if (found_key.type != BTRFS_DIR_INDEX_KEY) break; if (found_key.offset < ctx->pos) continue; if (found_key.offset > private->last_index) break; if (btrfs_should_delete_dir_index(&del_list, found_key.offset)) continue; di = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item); name_len = btrfs_dir_name_len(leaf, di); if ((total_len + sizeof(struct dir_entry) + name_len) >= PAGE_SIZE) { btrfs_release_path(path); ret = btrfs_filldir(private->filldir_buf, entries, ctx); if (ret) goto nopos; addr = private->filldir_buf; entries = 0; total_len = 0; goto again; } ftype = btrfs_dir_flags_to_ftype(btrfs_dir_flags(leaf, di)); entry = addr; name_ptr = (char *)(entry + 1); read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1), name_len); put_unaligned(name_len, &entry->name_len); put_unaligned(fs_ftype_to_dtype(ftype), &entry->type); btrfs_dir_item_key_to_cpu(leaf, di, &location); put_unaligned(location.objectid, &entry->ino); put_unaligned(found_key.offset, &entry->offset); entries++; addr += sizeof(struct dir_entry) + name_len; total_len += sizeof(struct dir_entry) + name_len; } /* Catch error encountered during iteration */ if (ret < 0) goto err; btrfs_release_path(path); ret = btrfs_filldir(private->filldir_buf, entries, ctx); if (ret) goto nopos; ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list); if (ret) goto nopos; /* * Stop new entries from being returned after we return the last * entry. * * New directory entries are assigned a strictly increasing * offset. This means that new entries created during readdir * are *guaranteed* to be seen in the future by that readdir. * This has broken buggy programs which operate on names as * they're returned by readdir. Until we re-use freed offsets * we have this hack to stop new entries from being returned * under the assumption that they'll never reach this huge * offset. * * This is being careful not to overflow 32bit loff_t unless the * last entry requires it because doing so has broken 32bit apps * in the past. */ if (ctx->pos >= INT_MAX) ctx->pos = LLONG_MAX; else ctx->pos = INT_MAX; nopos: ret = 0; err: if (put) btrfs_readdir_put_delayed_items(BTRFS_I(inode), &ins_list, &del_list); btrfs_free_path(path); return ret; } /* * This is somewhat expensive, updating the tree every time the * inode changes. But, it is most likely to find the inode in cache. * FIXME, needs more benchmarking...there are no reasons other than performance * to keep or drop this code. */ static int btrfs_dirty_inode(struct btrfs_inode *inode) { struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans; int ret; if (test_bit(BTRFS_INODE_DUMMY, &inode->runtime_flags)) return 0; trans = btrfs_join_transaction(root); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_update_inode(trans, inode); if (ret == -ENOSPC || ret == -EDQUOT) { /* whoops, lets try again with the full transaction */ btrfs_end_transaction(trans); trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_update_inode(trans, inode); } btrfs_end_transaction(trans); if (inode->delayed_node) btrfs_balance_delayed_items(fs_info); return ret; } /* * This is a copy of file_update_time. We need this so we can return error on * ENOSPC for updating the inode in the case of file write and mmap writes. */ static int btrfs_update_time(struct inode *inode, int flags) { struct btrfs_root *root = BTRFS_I(inode)->root; bool dirty; if (btrfs_root_readonly(root)) return -EROFS; dirty = inode_update_timestamps(inode, flags); return dirty ? btrfs_dirty_inode(BTRFS_I(inode)) : 0; } /* * helper to find a free sequence number in a given directory. This current * code is very simple, later versions will do smarter things in the btree */ int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index) { int ret = 0; if (dir->index_cnt == (u64)-1) { ret = btrfs_inode_delayed_dir_index_count(dir); if (ret) { ret = btrfs_set_inode_index_count(dir); if (ret) return ret; } } *index = dir->index_cnt; dir->index_cnt++; return ret; } static int btrfs_insert_inode_locked(struct inode *inode) { struct btrfs_iget_args args; args.ino = btrfs_ino(BTRFS_I(inode)); args.root = BTRFS_I(inode)->root; return insert_inode_locked4(inode, btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root), btrfs_find_actor, &args); } int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args, unsigned int *trans_num_items) { struct inode *dir = args->dir; struct inode *inode = args->inode; int ret; if (!args->orphan) { ret = fscrypt_setup_filename(dir, &args->dentry->d_name, 0, &args->fname); if (ret) return ret; } ret = posix_acl_create(dir, &inode->i_mode, &args->default_acl, &args->acl); if (ret) { fscrypt_free_filename(&args->fname); return ret; } /* 1 to add inode item */ *trans_num_items = 1; /* 1 to add compression property */ if (BTRFS_I(dir)->prop_compress) (*trans_num_items)++; /* 1 to add default ACL xattr */ if (args->default_acl) (*trans_num_items)++; /* 1 to add access ACL xattr */ if (args->acl) (*trans_num_items)++; #ifdef CONFIG_SECURITY /* 1 to add LSM xattr */ if (dir->i_security) (*trans_num_items)++; #endif if (args->orphan) { /* 1 to add orphan item */ (*trans_num_items)++; } else { /* * 1 to add dir item * 1 to add dir index * 1 to update parent inode item * * No need for 1 unit for the inode ref item because it is * inserted in a batch together with the inode item at * btrfs_create_new_inode(). */ *trans_num_items += 3; } return 0; } void btrfs_new_inode_args_destroy(struct btrfs_new_inode_args *args) { posix_acl_release(args->acl); posix_acl_release(args->default_acl); fscrypt_free_filename(&args->fname); } /* * Inherit flags from the parent inode. * * Currently only the compression flags and the cow flags are inherited. */ static void btrfs_inherit_iflags(struct btrfs_inode *inode, struct btrfs_inode *dir) { unsigned int flags; flags = dir->flags; if (flags & BTRFS_INODE_NOCOMPRESS) { inode->flags &= ~BTRFS_INODE_COMPRESS; inode->flags |= BTRFS_INODE_NOCOMPRESS; } else if (flags & BTRFS_INODE_COMPRESS) { inode->flags &= ~BTRFS_INODE_NOCOMPRESS; inode->flags |= BTRFS_INODE_COMPRESS; } if (flags & BTRFS_INODE_NODATACOW) { inode->flags |= BTRFS_INODE_NODATACOW; if (S_ISREG(inode->vfs_inode.i_mode)) inode->flags |= BTRFS_INODE_NODATASUM; } btrfs_sync_inode_flags_to_i_flags(&inode->vfs_inode); } int btrfs_create_new_inode(struct btrfs_trans_handle *trans, struct btrfs_new_inode_args *args) { struct timespec64 ts; struct inode *dir = args->dir; struct inode *inode = args->inode; const struct fscrypt_str *name = args->orphan ? NULL : &args->fname.disk_name; struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); struct btrfs_root *root; struct btrfs_inode_item *inode_item; struct btrfs_path *path; u64 objectid; struct btrfs_inode_ref *ref; struct btrfs_key key[2]; u32 sizes[2]; struct btrfs_item_batch batch; unsigned long ptr; int ret; bool xa_reserved = false; path = btrfs_alloc_path(); if (!path) return -ENOMEM; if (!args->subvol) BTRFS_I(inode)->root = btrfs_grab_root(BTRFS_I(dir)->root); root = BTRFS_I(inode)->root; ret = btrfs_init_file_extent_tree(BTRFS_I(inode)); if (ret) goto out; ret = btrfs_get_free_objectid(root, &objectid); if (ret) goto out; btrfs_set_inode_number(BTRFS_I(inode), objectid); ret = xa_reserve(&root->inodes, objectid, GFP_NOFS); if (ret) goto out; xa_reserved = true; if (args->orphan) { /* * O_TMPFILE, set link count to 0, so that after this point, we * fill in an inode item with the correct link count. */ set_nlink(inode, 0); } else { trace_btrfs_inode_request(dir); ret = btrfs_set_inode_index(BTRFS_I(dir), &BTRFS_I(inode)->dir_index); if (ret) goto out; } if (S_ISDIR(inode->i_mode)) BTRFS_I(inode)->index_cnt = BTRFS_DIR_START_INDEX; BTRFS_I(inode)->generation = trans->transid; inode->i_generation = BTRFS_I(inode)->generation; /* * We don't have any capability xattrs set here yet, shortcut any * queries for the xattrs here. If we add them later via the inode * security init path or any other path this flag will be cleared. */ set_bit(BTRFS_INODE_NO_CAP_XATTR, &BTRFS_I(inode)->runtime_flags); /* * Subvolumes don't inherit flags from their parent directory. * Originally this was probably by accident, but we probably can't * change it now without compatibility issues. */ if (!args->subvol) btrfs_inherit_iflags(BTRFS_I(inode), BTRFS_I(dir)); if (S_ISREG(inode->i_mode)) { if (btrfs_test_opt(fs_info, NODATASUM)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; if (btrfs_test_opt(fs_info, NODATACOW)) BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW | BTRFS_INODE_NODATASUM; } ret = btrfs_insert_inode_locked(inode); if (ret < 0) { if (!args->orphan) BTRFS_I(dir)->index_cnt--; goto out; } /* * We could have gotten an inode number from somebody who was fsynced * and then removed in this same transaction, so let's just set full * sync since it will be a full sync anyway and this will blow away the * old info in the log. */ btrfs_set_inode_full_sync(BTRFS_I(inode)); key[0].objectid = objectid; key[0].type = BTRFS_INODE_ITEM_KEY; key[0].offset = 0; sizes[0] = sizeof(struct btrfs_inode_item); if (!args->orphan) { /* * Start new inodes with an inode_ref. This is slightly more * efficient for small numbers of hard links since they will * be packed into one item. Extended refs will kick in if we * add more hard links than can fit in the ref item. */ key[1].objectid = objectid; key[1].type = BTRFS_INODE_REF_KEY; if (args->subvol) { key[1].offset = objectid; sizes[1] = 2 + sizeof(*ref); } else { key[1].offset = btrfs_ino(BTRFS_I(dir)); sizes[1] = name->len + sizeof(*ref); } } batch.keys = &key[0]; batch.data_sizes = &sizes[0]; batch.total_data_size = sizes[0] + (args->orphan ? 0 : sizes[1]); batch.nr = args->orphan ? 1 : 2; ret = btrfs_insert_empty_items(trans, root, path, &batch); if (ret != 0) { btrfs_abort_transaction(trans, ret); goto discard; } ts = simple_inode_init_ts(inode); BTRFS_I(inode)->i_otime_sec = ts.tv_sec; BTRFS_I(inode)->i_otime_nsec = ts.tv_nsec; /* * We're going to fill the inode item now, so at this point the inode * must be fully initialized. */ inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_inode_item); memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item, sizeof(*inode_item)); fill_inode_item(trans, path->nodes[0], inode_item, inode); if (!args->orphan) { ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, struct btrfs_inode_ref); ptr = (unsigned long)(ref + 1); if (args->subvol) { btrfs_set_inode_ref_name_len(path->nodes[0], ref, 2); btrfs_set_inode_ref_index(path->nodes[0], ref, 0); write_extent_buffer(path->nodes[0], "..", ptr, 2); } else { btrfs_set_inode_ref_name_len(path->nodes[0], ref, name->len); btrfs_set_inode_ref_index(path->nodes[0], ref, BTRFS_I(inode)->dir_index); write_extent_buffer(path->nodes[0], name->name, ptr, name->len); } } btrfs_mark_buffer_dirty(trans, path->nodes[0]); /* * We don't need the path anymore, plus inheriting properties, adding * ACLs, security xattrs, orphan item or adding the link, will result in * allocating yet another path. So just free our path. */ btrfs_free_path(path); path = NULL; if (args->subvol) { struct inode *parent; /* * Subvolumes inherit properties from their parent subvolume, * not the directory they were created in. */ parent = btrfs_iget(BTRFS_FIRST_FREE_OBJECTID, BTRFS_I(dir)->root); if (IS_ERR(parent)) { ret = PTR_ERR(parent); } else { ret = btrfs_inode_inherit_props(trans, inode, parent); iput(parent); } } else { ret = btrfs_inode_inherit_props(trans, inode, dir); } if (ret) { btrfs_err(fs_info, "error inheriting props for ino %llu (root %llu): %d", btrfs_ino(BTRFS_I(inode)), btrfs_root_id(root), ret); } /* * Subvolumes don't inherit ACLs or get passed to the LSM. This is * probably a bug. */ if (!args->subvol) { ret = btrfs_init_inode_security(trans, args); if (ret) { btrfs_abort_transaction(trans, ret); goto discard; } } ret = btrfs_add_inode_to_root(BTRFS_I(inode), false); if (WARN_ON(ret)) { /* Shouldn't happen, we used xa_reserve() before. */ btrfs_abort_transaction(trans, ret); goto discard; } trace_btrfs_inode_new(inode); btrfs_set_inode_last_trans(trans, BTRFS_I(inode)); btrfs_update_root_times(trans, root); if (args->orphan) { ret = btrfs_orphan_add(trans, BTRFS_I(inode)); } else { ret = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), name, 0, BTRFS_I(inode)->dir_index); } if (ret) { btrfs_abort_transaction(trans, ret); goto discard; } return 0; discard: /* * discard_new_inode() calls iput(), but the caller owns the reference * to the inode. */ ihold(inode); discard_new_inode(inode); out: if (xa_reserved) xa_release(&root->inodes, objectid); btrfs_free_path(path); return ret; } /* * utility function to add 'inode' into 'parent_inode' with * a give name and a given sequence number. * if 'add_backref' is true, also insert a backref from the * inode to the parent directory. */ int btrfs_add_link(struct btrfs_trans_handle *trans, struct btrfs_inode *parent_inode, struct btrfs_inode *inode, const struct fscrypt_str *name, int add_backref, u64 index) { int ret = 0; struct btrfs_key key; struct btrfs_root *root = parent_inode->root; u64 ino = btrfs_ino(inode); u64 parent_ino = btrfs_ino(parent_inode); if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { memcpy(&key, &inode->root->root_key, sizeof(key)); } else { key.objectid = ino; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; } if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { ret = btrfs_add_root_ref(trans, key.objectid, btrfs_root_id(root), parent_ino, index, name); } else if (add_backref) { ret = btrfs_insert_inode_ref(trans, root, name, ino, parent_ino, index); } /* Nothing to clean up yet */ if (ret) return ret; ret = btrfs_insert_dir_item(trans, name, parent_inode, &key, btrfs_inode_type(&inode->vfs_inode), index); if (ret == -EEXIST || ret == -EOVERFLOW) goto fail_dir_item; else if (ret) { btrfs_abort_transaction(trans, ret); return ret; } btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size + name->len * 2); inode_inc_iversion(&parent_inode->vfs_inode); /* * If we are replaying a log tree, we do not want to update the mtime * and ctime of the parent directory with the current time, since the * log replay procedure is responsible for setting them to their correct * values (the ones it had when the fsync was done). */ if (!test_bit(BTRFS_FS_LOG_RECOVERING, &root->fs_info->flags)) inode_set_mtime_to_ts(&parent_inode->vfs_inode, inode_set_ctime_current(&parent_inode->vfs_inode)); ret = btrfs_update_inode(trans, parent_inode); if (ret) btrfs_abort_transaction(trans, ret); return ret; fail_dir_item: if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { u64 local_index; int err; err = btrfs_del_root_ref(trans, key.objectid, btrfs_root_id(root), parent_ino, &local_index, name); if (err) btrfs_abort_transaction(trans, err); } else if (add_backref) { u64 local_index; int err; err = btrfs_del_inode_ref(trans, root, name, ino, parent_ino, &local_index); if (err) btrfs_abort_transaction(trans, err); } /* Return the original error code */ return ret; } static int btrfs_create_common(struct inode *dir, struct dentry *dentry, struct inode *inode) { struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_new_inode_args new_inode_args = { .dir = dir, .dentry = dentry, .inode = inode, }; unsigned int trans_num_items; struct btrfs_trans_handle *trans; int err; err = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items); if (err) goto out_inode; trans = btrfs_start_transaction(root, trans_num_items); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_new_inode_args; } err = btrfs_create_new_inode(trans, &new_inode_args); if (!err) d_instantiate_new(dentry, inode); btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); out_new_inode_args: btrfs_new_inode_args_destroy(&new_inode_args); out_inode: if (err) iput(inode); return err; } static int btrfs_mknod(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev) { struct inode *inode; inode = new_inode(dir->i_sb); if (!inode) return -ENOMEM; inode_init_owner(idmap, inode, dir, mode); inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, rdev); return btrfs_create_common(dir, dentry, inode); } static int btrfs_create(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { struct inode *inode; inode = new_inode(dir->i_sb); if (!inode) return -ENOMEM; inode_init_owner(idmap, inode, dir, mode); inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; inode->i_mapping->a_ops = &btrfs_aops; return btrfs_create_common(dir, dentry, inode); } static int btrfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) { struct btrfs_trans_handle *trans = NULL; struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode = d_inode(old_dentry); struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); struct fscrypt_name fname; u64 index; int err; int drop_inode = 0; /* do not allow sys_link's with other subvols of the same device */ if (btrfs_root_id(root) != btrfs_root_id(BTRFS_I(inode)->root)) return -EXDEV; if (inode->i_nlink >= BTRFS_LINK_MAX) return -EMLINK; err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &fname); if (err) goto fail; err = btrfs_set_inode_index(BTRFS_I(dir), &index); if (err) goto fail; /* * 2 items for inode and inode ref * 2 items for dir items * 1 item for parent inode * 1 item for orphan item deletion if O_TMPFILE */ trans = btrfs_start_transaction(root, inode->i_nlink ? 5 : 6); if (IS_ERR(trans)) { err = PTR_ERR(trans); trans = NULL; goto fail; } /* There are several dir indexes for this inode, clear the cache. */ BTRFS_I(inode)->dir_index = 0ULL; inc_nlink(inode); inode_inc_iversion(inode); inode_set_ctime_current(inode); ihold(inode); set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags); err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode), &fname.disk_name, 1, index); if (err) { drop_inode = 1; } else { struct dentry *parent = dentry->d_parent; err = btrfs_update_inode(trans, BTRFS_I(inode)); if (err) goto fail; if (inode->i_nlink == 1) { /* * If new hard link count is 1, it's a file created * with open(2) O_TMPFILE flag. */ err = btrfs_orphan_del(trans, BTRFS_I(inode)); if (err) goto fail; } d_instantiate(dentry, inode); btrfs_log_new_name(trans, old_dentry, NULL, 0, parent); } fail: fscrypt_free_filename(&fname); if (trans) btrfs_end_transaction(trans); if (drop_inode) { inode_dec_link_count(inode); iput(inode); } btrfs_btree_balance_dirty(fs_info); return err; } static int btrfs_mkdir(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, umode_t mode) { struct inode *inode; inode = new_inode(dir->i_sb); if (!inode) return -ENOMEM; inode_init_owner(idmap, inode, dir, S_IFDIR | mode); inode->i_op = &btrfs_dir_inode_operations; inode->i_fop = &btrfs_dir_file_operations; return btrfs_create_common(dir, dentry, inode); } static noinline int uncompress_inline(struct btrfs_path *path, struct folio *folio, struct btrfs_file_extent_item *item) { int ret; struct extent_buffer *leaf = path->nodes[0]; char *tmp; size_t max_size; unsigned long inline_size; unsigned long ptr; int compress_type; compress_type = btrfs_file_extent_compression(leaf, item); max_size = btrfs_file_extent_ram_bytes(leaf, item); inline_size = btrfs_file_extent_inline_item_len(leaf, path->slots[0]); tmp = kmalloc(inline_size, GFP_NOFS); if (!tmp) return -ENOMEM; ptr = btrfs_file_extent_inline_start(item); read_extent_buffer(leaf, tmp, ptr, inline_size); max_size = min_t(unsigned long, PAGE_SIZE, max_size); ret = btrfs_decompress(compress_type, tmp, folio, 0, inline_size, max_size); /* * decompression code contains a memset to fill in any space between the end * of the uncompressed data and the end of max_size in case the decompressed * data ends up shorter than ram_bytes. That doesn't cover the hole between * the end of an inline extent and the beginning of the next block, so we * cover that region here. */ if (max_size < PAGE_SIZE) folio_zero_range(folio, max_size, PAGE_SIZE - max_size); kfree(tmp); return ret; } static int read_inline_extent(struct btrfs_inode *inode, struct btrfs_path *path, struct folio *folio) { struct btrfs_file_extent_item *fi; void *kaddr; size_t copy_size; if (!folio || folio_test_uptodate(folio)) return 0; ASSERT(folio_pos(folio) == 0); fi = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_file_extent_item); if (btrfs_file_extent_compression(path->nodes[0], fi) != BTRFS_COMPRESS_NONE) return uncompress_inline(path, folio, fi); copy_size = min_t(u64, PAGE_SIZE, btrfs_file_extent_ram_bytes(path->nodes[0], fi)); kaddr = kmap_local_folio(folio, 0); read_extent_buffer(path->nodes[0], kaddr, btrfs_file_extent_inline_start(fi), copy_size); kunmap_local(kaddr); if (copy_size < PAGE_SIZE) folio_zero_range(folio, copy_size, PAGE_SIZE - copy_size); return 0; } /* * Lookup the first extent overlapping a range in a file. * * @inode: file to search in * @page: page to read extent data into if the extent is inline * @start: file offset * @len: length of range starting at @start * * Return the first &struct extent_map which overlaps the given range, reading * it from the B-tree and caching it if necessary. Note that there may be more * extents which overlap the given range after the returned extent_map. * * If @page is not NULL and the extent is inline, this also reads the extent * data directly into the page and marks the extent up to date in the io_tree. * * Return: ERR_PTR on error, non-NULL extent_map on success. */ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode, struct folio *folio, u64 start, u64 len) { struct btrfs_fs_info *fs_info = inode->root->fs_info; int ret = 0; u64 extent_start = 0; u64 extent_end = 0; u64 objectid = btrfs_ino(inode); int extent_type = -1; struct btrfs_path *path = NULL; struct btrfs_root *root = inode->root; struct btrfs_file_extent_item *item; struct extent_buffer *leaf; struct btrfs_key found_key; struct extent_map *em = NULL; struct extent_map_tree *em_tree = &inode->extent_tree; read_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); read_unlock(&em_tree->lock); if (em) { if (em->start > start || em->start + em->len <= start) free_extent_map(em); else if (em->disk_bytenr == EXTENT_MAP_INLINE && folio) free_extent_map(em); else goto out; } em = alloc_extent_map(); if (!em) { ret = -ENOMEM; goto out; } em->start = EXTENT_MAP_HOLE; em->disk_bytenr = EXTENT_MAP_HOLE; em->len = (u64)-1; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } /* Chances are we'll be called again, so go ahead and do readahead */ path->reada = READA_FORWARD; /* * The same explanation in load_free_space_cache applies here as well, * we only read when we're loading the free space cache, and at that * point the commit_root has everything we need. */ if (btrfs_is_free_space_inode(inode)) { path->search_commit_root = 1; path->skip_locking = 1; } ret = btrfs_lookup_file_extent(NULL, root, path, objectid, start, 0); if (ret < 0) { goto out; } else if (ret > 0) { if (path->slots[0] == 0) goto not_found; path->slots[0]--; ret = 0; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid != objectid || found_key.type != BTRFS_EXTENT_DATA_KEY) { /* * If we backup past the first extent we want to move forward * and see if there is an extent in front of us, otherwise we'll * say there is a hole for our whole search range which can * cause problems. */ extent_end = start; goto next; } extent_type = btrfs_file_extent_type(leaf, item); extent_start = found_key.offset; extent_end = btrfs_file_extent_end(path); if (extent_type == BTRFS_FILE_EXTENT_REG || extent_type == BTRFS_FILE_EXTENT_PREALLOC) { /* Only regular file could have regular/prealloc extent */ if (!S_ISREG(inode->vfs_inode.i_mode)) { ret = -EUCLEAN; btrfs_crit(fs_info, "regular/prealloc extent found for non-regular inode %llu", btrfs_ino(inode)); goto out; } trace_btrfs_get_extent_show_fi_regular(inode, leaf, item, extent_start); } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { trace_btrfs_get_extent_show_fi_inline(inode, leaf, item, path->slots[0], extent_start); } next: if (start >= extent_end) { path->slots[0]++; if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto out; else if (ret > 0) goto not_found; leaf = path->nodes[0]; } btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid != objectid || found_key.type != BTRFS_EXTENT_DATA_KEY) goto not_found; if (start + len <= found_key.offset) goto not_found; if (start > found_key.offset) goto next; /* New extent overlaps with existing one */ em->start = start; em->len = found_key.offset - start; em->disk_bytenr = EXTENT_MAP_HOLE; goto insert; } btrfs_extent_item_to_extent_map(inode, path, item, em); if (extent_type == BTRFS_FILE_EXTENT_REG || extent_type == BTRFS_FILE_EXTENT_PREALLOC) { goto insert; } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { /* * Inline extent can only exist at file offset 0. This is * ensured by tree-checker and inline extent creation path. * Thus all members representing file offsets should be zero. */ ASSERT(extent_start == 0); ASSERT(em->start == 0); /* * btrfs_extent_item_to_extent_map() should have properly * initialized em members already. * * Other members are not utilized for inline extents. */ ASSERT(em->disk_bytenr == EXTENT_MAP_INLINE); ASSERT(em->len == fs_info->sectorsize); ret = read_inline_extent(inode, path, folio); if (ret < 0) goto out; goto insert; } not_found: em->start = start; em->len = len; em->disk_bytenr = EXTENT_MAP_HOLE; insert: ret = 0; btrfs_release_path(path); if (em->start > start || extent_map_end(em) <= start) { btrfs_err(fs_info, "bad extent! em: [%llu %llu] passed [%llu %llu]", em->start, em->len, start, len); ret = -EIO; goto out; } write_lock(&em_tree->lock); ret = btrfs_add_extent_mapping(inode, &em, start, len); write_unlock(&em_tree->lock); out: btrfs_free_path(path); trace_btrfs_get_extent(root, inode, em); if (ret) { free_extent_map(em); return ERR_PTR(ret); } return em; } static bool btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr) { struct btrfs_block_group *block_group; bool readonly = false; block_group = btrfs_lookup_block_group(fs_info, bytenr); if (!block_group || block_group->ro) readonly = true; if (block_group) btrfs_put_block_group(block_group); return readonly; } /* * Check if we can do nocow write into the range [@offset, @offset + @len) * * @offset: File offset * @len: The length to write, will be updated to the nocow writeable * range * @orig_start: (optional) Return the original file offset of the file extent * @orig_len: (optional) Return the original on-disk length of the file extent * @ram_bytes: (optional) Return the ram_bytes of the file extent * @strict: if true, omit optimizations that might force us into unnecessary * cow. e.g., don't trust generation number. * * Return: * >0 and update @len if we can do nocow write * 0 if we can't do nocow write * <0 if error happened * * NOTE: This only checks the file extents, caller is responsible to wait for * any ordered extents. */ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len, struct btrfs_file_extent *file_extent, bool nowait, bool strict) { struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); struct can_nocow_file_extent_args nocow_args = { 0 }; struct btrfs_path *path; int ret; struct extent_buffer *leaf; struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_file_extent_item *fi; struct btrfs_key key; int found_type; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->nowait = nowait; ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(BTRFS_I(inode)), offset, 0); if (ret < 0) goto out; if (ret == 1) { if (path->slots[0] == 0) { /* can't find the item, must cow */ ret = 0; goto out; } path->slots[0]--; } ret = 0; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); if (key.objectid != btrfs_ino(BTRFS_I(inode)) || key.type != BTRFS_EXTENT_DATA_KEY) { /* not our file or wrong item type, must cow */ goto out; } if (key.offset > offset) { /* Wrong offset, must cow */ goto out; } if (btrfs_file_extent_end(path) <= offset) goto out; fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); found_type = btrfs_file_extent_type(leaf, fi); nocow_args.start = offset; nocow_args.end = offset + *len - 1; nocow_args.strict = strict; nocow_args.free_path = true; ret = can_nocow_file_extent(path, &key, BTRFS_I(inode), &nocow_args); /* can_nocow_file_extent() has freed the path. */ path = NULL; if (ret != 1) { /* Treat errors as not being able to NOCOW. */ ret = 0; goto out; } ret = 0; if (btrfs_extent_readonly(fs_info, nocow_args.file_extent.disk_bytenr + nocow_args.file_extent.offset)) goto out; if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && found_type == BTRFS_FILE_EXTENT_PREALLOC) { u64 range_end; range_end = round_up(offset + nocow_args.file_extent.num_bytes, root->fs_info->sectorsize) - 1; ret = test_range_bit_exists(io_tree, offset, range_end, EXTENT_DELALLOC); if (ret) { ret = -EAGAIN; goto out; } } if (file_extent) memcpy(file_extent, &nocow_args.file_extent, sizeof(*file_extent)); *len = nocow_args.file_extent.num_bytes; ret = 1; out: btrfs_free_path(path); return ret; } /* The callers of this must take lock_extent() */ struct extent_map *btrfs_create_io_em(struct btrfs_inode *inode, u64 start, const struct btrfs_file_extent *file_extent, int type) { struct extent_map *em; int ret; /* * Note the missing NOCOW type. * * For pure NOCOW writes, we should not create an io extent map, but * just reusing the existing one. * Only PREALLOC writes (NOCOW write into preallocated range) can * create an io extent map. */ ASSERT(type == BTRFS_ORDERED_PREALLOC || type == BTRFS_ORDERED_COMPRESSED || type == BTRFS_ORDERED_REGULAR); switch (type) { case BTRFS_ORDERED_PREALLOC: /* We're only referring part of a larger preallocated extent. */ ASSERT(file_extent->num_bytes <= file_extent->ram_bytes); break; case BTRFS_ORDERED_REGULAR: /* COW results a new extent matching our file extent size. */ ASSERT(file_extent->disk_num_bytes == file_extent->num_bytes); ASSERT(file_extent->ram_bytes == file_extent->num_bytes); /* Since it's a new extent, we should not have any offset. */ ASSERT(file_extent->offset == 0); break; case BTRFS_ORDERED_COMPRESSED: /* Must be compressed. */ ASSERT(file_extent->compression != BTRFS_COMPRESS_NONE); /* * Encoded write can make us to refer to part of the * uncompressed extent. */ ASSERT(file_extent->num_bytes <= file_extent->ram_bytes); break; } em = alloc_extent_map(); if (!em) return ERR_PTR(-ENOMEM); em->start = start; em->len = file_extent->num_bytes; em->disk_bytenr = file_extent->disk_bytenr; em->disk_num_bytes = file_extent->disk_num_bytes; em->ram_bytes = file_extent->ram_bytes; em->generation = -1; em->offset = file_extent->offset; em->flags |= EXTENT_FLAG_PINNED; if (type == BTRFS_ORDERED_COMPRESSED) extent_map_set_compression(em, file_extent->compression); ret = btrfs_replace_extent_map_range(inode, em, true); if (ret) { free_extent_map(em); return ERR_PTR(ret); } /* em got 2 refs now, callers needs to do free_extent_map once. */ return em; } /* * For release_folio() and invalidate_folio() we have a race window where * folio_end_writeback() is called but the subpage spinlock is not yet released. * If we continue to release/invalidate the page, we could cause use-after-free * for subpage spinlock. So this function is to spin and wait for subpage * spinlock. */ static void wait_subpage_spinlock(struct folio *folio) { struct btrfs_fs_info *fs_info = folio_to_fs_info(folio); struct btrfs_subpage *subpage; if (!btrfs_is_subpage(fs_info, folio->mapping)) return; ASSERT(folio_test_private(folio) && folio_get_private(folio)); subpage = folio_get_private(folio); /* * This may look insane as we just acquire the spinlock and release it, * without doing anything. But we just want to make sure no one is * still holding the subpage spinlock. * And since the page is not dirty nor writeback, and we have page * locked, the only possible way to hold a spinlock is from the endio * function to clear page writeback. * * Here we just acquire the spinlock so that all existing callers * should exit and we're safe to release/invalidate the page. */ spin_lock_irq(&subpage->lock); spin_unlock_irq(&subpage->lock); } static int btrfs_launder_folio(struct folio *folio) { return btrfs_qgroup_free_data(folio_to_inode(folio), NULL, folio_pos(folio), PAGE_SIZE, NULL); } static bool __btrfs_release_folio(struct folio *folio, gfp_t gfp_flags) { if (try_release_extent_mapping(folio, gfp_flags)) { wait_subpage_spinlock(folio); clear_folio_extent_mapped(folio); return true; } return false; } static bool btrfs_release_folio(struct folio *folio, gfp_t gfp_flags) { if (folio_test_writeback(folio) || folio_test_dirty(folio)) return false; return __btrfs_release_folio(folio, gfp_flags); } #ifdef CONFIG_MIGRATION static int btrfs_migrate_folio(struct address_space *mapping, struct folio *dst, struct folio *src, enum migrate_mode mode) { int ret = filemap_migrate_folio(mapping, dst, src, mode); if (ret != MIGRATEPAGE_SUCCESS) return ret; if (folio_test_ordered(src)) { folio_clear_ordered(src); folio_set_ordered(dst); } return MIGRATEPAGE_SUCCESS; } #else #define btrfs_migrate_folio NULL #endif static void btrfs_invalidate_folio(struct folio *folio, size_t offset, size_t length) { struct btrfs_inode *inode = folio_to_inode(folio); struct btrfs_fs_info *fs_info = inode->root->fs_info; struct extent_io_tree *tree = &inode->io_tree; struct extent_state *cached_state = NULL; u64 page_start = folio_pos(folio); u64 page_end = page_start + folio_size(folio) - 1; u64 cur; int inode_evicting = inode->vfs_inode.i_state & I_FREEING; /* * We have folio locked so no new ordered extent can be created on this * page, nor bio can be submitted for this folio. * * But already submitted bio can still be finished on this folio. * Furthermore, endio function won't skip folio which has Ordered * (Private2) already cleared, so it's possible for endio and * invalidate_folio to do the same ordered extent accounting twice * on one folio. * * So here we wait for any submitted bios to finish, so that we won't * do double ordered extent accounting on the same folio. */ folio_wait_writeback(folio); wait_subpage_spinlock(folio); /* * For subpage case, we have call sites like * btrfs_punch_hole_lock_range() which passes range not aligned to * sectorsize. * If the range doesn't cover the full folio, we don't need to and * shouldn't clear page extent mapped, as folio->private can still * record subpage dirty bits for other part of the range. * * For cases that invalidate the full folio even the range doesn't * cover the full folio, like invalidating the last folio, we're * still safe to wait for ordered extent to finish. */ if (!(offset == 0 && length == folio_size(folio))) { btrfs_release_folio(folio, GFP_NOFS); return; } if (!inode_evicting) lock_extent(tree, page_start, page_end, &cached_state); cur = page_start; while (cur < page_end) { struct btrfs_ordered_extent *ordered; u64 range_end; u32 range_len; u32 extra_flags = 0; ordered = btrfs_lookup_first_ordered_range(inode, cur, page_end + 1 - cur); if (!ordered) { range_end = page_end; /* * No ordered extent covering this range, we are safe * to delete all extent states in the range. */ extra_flags = EXTENT_CLEAR_ALL_BITS; goto next; } if (ordered->file_offset > cur) { /* * There is a range between [cur, oe->file_offset) not * covered by any ordered extent. * We are safe to delete all extent states, and handle * the ordered extent in the next iteration. */ range_end = ordered->file_offset - 1; extra_flags = EXTENT_CLEAR_ALL_BITS; goto next; } range_end = min(ordered->file_offset + ordered->num_bytes - 1, page_end); ASSERT(range_end + 1 - cur < U32_MAX); range_len = range_end + 1 - cur; if (!btrfs_folio_test_ordered(fs_info, folio, cur, range_len)) { /* * If Ordered (Private2) is cleared, it means endio has * already been executed for the range. * We can't delete the extent states as * btrfs_finish_ordered_io() may still use some of them. */ goto next; } btrfs_folio_clear_ordered(fs_info, folio, cur, range_len); /* * IO on this page will never be started, so we need to account * for any ordered extents now. Don't clear EXTENT_DELALLOC_NEW * here, must leave that up for the ordered extent completion. * * This will also unlock the range for incoming * btrfs_finish_ordered_io(). */ if (!inode_evicting) clear_extent_bit(tree, cur, range_end, EXTENT_DELALLOC | EXTENT_LOCKED | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, &cached_state); spin_lock_irq(&inode->ordered_tree_lock); set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags); ordered->truncated_len = min(ordered->truncated_len, cur - ordered->file_offset); spin_unlock_irq(&inode->ordered_tree_lock); /* * If the ordered extent has finished, we're safe to delete all * the extent states of the range, otherwise * btrfs_finish_ordered_io() will get executed by endio for * other pages, so we can't delete extent states. */ if (btrfs_dec_test_ordered_pending(inode, &ordered, cur, range_end + 1 - cur)) { btrfs_finish_ordered_io(ordered); /* * The ordered extent has finished, now we're again * safe to delete all extent states of the range. */ extra_flags = EXTENT_CLEAR_ALL_BITS; } next: if (ordered) btrfs_put_ordered_extent(ordered); /* * Qgroup reserved space handler * Sector(s) here will be either: * * 1) Already written to disk or bio already finished * Then its QGROUP_RESERVED bit in io_tree is already cleared. * Qgroup will be handled by its qgroup_record then. * btrfs_qgroup_free_data() call will do nothing here. * * 2) Not written to disk yet * Then btrfs_qgroup_free_data() call will clear the * QGROUP_RESERVED bit of its io_tree, and free the qgroup * reserved data space. * Since the IO will never happen for this page. */ btrfs_qgroup_free_data(inode, NULL, cur, range_end + 1 - cur, NULL); if (!inode_evicting) { clear_extent_bit(tree, cur, range_end, EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG | extra_flags, &cached_state); } cur = range_end + 1; } /* * We have iterated through all ordered extents of the page, the page * should not have Ordered (Private2) anymore, or the above iteration * did something wrong. */ ASSERT(!folio_test_ordered(folio)); btrfs_folio_clear_checked(fs_info, folio, folio_pos(folio), folio_size(folio)); if (!inode_evicting) __btrfs_release_folio(folio, GFP_NOFS); clear_folio_extent_mapped(folio); } static int btrfs_truncate(struct btrfs_inode *inode, bool skip_writeback) { struct btrfs_truncate_control control = { .inode = inode, .ino = btrfs_ino(inode), .min_type = BTRFS_EXTENT_DATA_KEY, .clear_extent_range = true, }; struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_block_rsv *rsv; int ret; struct btrfs_trans_handle *trans; u64 mask = fs_info->sectorsize - 1; const u64 min_size = btrfs_calc_metadata_size(fs_info, 1); if (!skip_writeback) { ret = btrfs_wait_ordered_range(inode, inode->vfs_inode.i_size & (~mask), (u64)-1); if (ret) return ret; } /* * Yes ladies and gentlemen, this is indeed ugly. We have a couple of * things going on here: * * 1) We need to reserve space to update our inode. * * 2) We need to have something to cache all the space that is going to * be free'd up by the truncate operation, but also have some slack * space reserved in case it uses space during the truncate (thank you * very much snapshotting). * * And we need these to be separate. The fact is we can use a lot of * space doing the truncate, and we have no earthly idea how much space * we will use, so we need the truncate reservation to be separate so it * doesn't end up using space reserved for updating the inode. We also * need to be able to stop the transaction and start a new one, which * means we need to be able to update the inode several times, and we * have no idea of knowing how many times that will be, so we can't just * reserve 1 item for the entirety of the operation, so that has to be * done separately as well. * * So that leaves us with * * 1) rsv - for the truncate reservation, which we will steal from the * transaction reservation. * 2) fs_info->trans_block_rsv - this will have 1 items worth left for * updating the inode. */ rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP); if (!rsv) return -ENOMEM; rsv->size = min_size; rsv->failfast = true; /* * 1 for the truncate slack space * 1 for updating the inode. */ trans = btrfs_start_transaction(root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } /* Migrate the slack space for the truncate to our reserve */ ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv, min_size, false); /* * We have reserved 2 metadata units when we started the transaction and * min_size matches 1 unit, so this should never fail, but if it does, * it's not critical we just fail truncation. */ if (WARN_ON(ret)) { btrfs_end_transaction(trans); goto out; } trans->block_rsv = rsv; while (1) { struct extent_state *cached_state = NULL; const u64 new_size = inode->vfs_inode.i_size; const u64 lock_start = ALIGN_DOWN(new_size, fs_info->sectorsize); control.new_size = new_size; lock_extent(&inode->io_tree, lock_start, (u64)-1, &cached_state); /* * We want to drop from the next block forward in case this new * size is not block aligned since we will be keeping the last * block of the extent just the way it is. */ btrfs_drop_extent_map_range(inode, ALIGN(new_size, fs_info->sectorsize), (u64)-1, false); ret = btrfs_truncate_inode_items(trans, root, &control); inode_sub_bytes(&inode->vfs_inode, control.sub_bytes); btrfs_inode_safe_disk_i_size_write(inode, control.last_size); unlock_extent(&inode->io_tree, lock_start, (u64)-1, &cached_state); trans->block_rsv = &fs_info->trans_block_rsv; if (ret != -ENOSPC && ret != -EAGAIN) break; ret = btrfs_update_inode(trans, inode); if (ret) break; btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); trans = btrfs_start_transaction(root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; break; } btrfs_block_rsv_release(fs_info, rsv, -1, NULL); ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv, min_size, false); /* * We have reserved 2 metadata units when we started the * transaction and min_size matches 1 unit, so this should never * fail, but if it does, it's not critical we just fail truncation. */ if (WARN_ON(ret)) break; trans->block_rsv = rsv; } /* * We can't call btrfs_truncate_block inside a trans handle as we could * deadlock with freeze, if we got BTRFS_NEED_TRUNCATE_BLOCK then we * know we've truncated everything except the last little bit, and can * do btrfs_truncate_block and then update the disk_i_size. */ if (ret == BTRFS_NEED_TRUNCATE_BLOCK) { btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); ret = btrfs_truncate_block(inode, inode->vfs_inode.i_size, 0, 0); if (ret) goto out; trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } btrfs_inode_safe_disk_i_size_write(inode, 0); } if (trans) { int ret2; trans->block_rsv = &fs_info->trans_block_rsv; ret2 = btrfs_update_inode(trans, inode); if (ret2 && !ret) ret = ret2; ret2 = btrfs_end_transaction(trans); if (ret2 && !ret) ret = ret2; btrfs_btree_balance_dirty(fs_info); } out: btrfs_free_block_rsv(fs_info, rsv); /* * So if we truncate and then write and fsync we normally would just * write the extents that changed, which is a problem if we need to * first truncate that entire inode. So set this flag so we write out * all of the extents in the inode to the sync log so we're completely * safe. * * If no extents were dropped or trimmed we don't need to force the next * fsync to truncate all the inode's items from the log and re-log them * all. This means the truncate operation did not change the file size, * or changed it to a smaller size but there was only an implicit hole * between the old i_size and the new i_size, and there were no prealloc * extents beyond i_size to drop. */ if (control.extents_found > 0) btrfs_set_inode_full_sync(inode); return ret; } struct inode *btrfs_new_subvol_inode(struct mnt_idmap *idmap, struct inode *dir) { struct inode *inode; inode = new_inode(dir->i_sb); if (inode) { /* * Subvolumes don't inherit the sgid bit or the parent's gid if * the parent's sgid bit is set. This is probably a bug. */ inode_init_owner(idmap, inode, NULL, S_IFDIR | (~current_umask() & S_IRWXUGO)); inode->i_op = &btrfs_dir_inode_operations; inode->i_fop = &btrfs_dir_file_operations; } return inode; } struct inode *btrfs_alloc_inode(struct super_block *sb) { struct btrfs_fs_info *fs_info = btrfs_sb(sb); struct btrfs_inode *ei; struct inode *inode; ei = alloc_inode_sb(sb, btrfs_inode_cachep, GFP_KERNEL); if (!ei) return NULL; ei->root = NULL; ei->generation = 0; ei->last_trans = 0; ei->last_sub_trans = 0; ei->logged_trans = 0; ei->delalloc_bytes = 0; ei->new_delalloc_bytes = 0; ei->defrag_bytes = 0; ei->disk_i_size = 0; ei->flags = 0; ei->ro_flags = 0; /* * ->index_cnt will be properly initialized later when creating a new * inode (btrfs_create_new_inode()) or when reading an existing inode * from disk (btrfs_read_locked_inode()). */ ei->csum_bytes = 0; ei->dir_index = 0; ei->last_unlink_trans = 0; ei->last_reflink_trans = 0; ei->last_log_commit = 0; spin_lock_init(&ei->lock); ei->outstanding_extents = 0; if (sb->s_magic != BTRFS_TEST_MAGIC) btrfs_init_metadata_block_rsv(fs_info, &ei->block_rsv, BTRFS_BLOCK_RSV_DELALLOC); ei->runtime_flags = 0; ei->prop_compress = BTRFS_COMPRESS_NONE; ei->defrag_compress = BTRFS_COMPRESS_NONE; ei->delayed_node = NULL; ei->i_otime_sec = 0; ei->i_otime_nsec = 0; inode = &ei->vfs_inode; extent_map_tree_init(&ei->extent_tree); /* This io tree sets the valid inode. */ extent_io_tree_init(fs_info, &ei->io_tree, IO_TREE_INODE_IO); ei->io_tree.inode = ei; ei->file_extent_tree = NULL; mutex_init(&ei->log_mutex); spin_lock_init(&ei->ordered_tree_lock); ei->ordered_tree = RB_ROOT; ei->ordered_tree_last = NULL; INIT_LIST_HEAD(&ei->delalloc_inodes); INIT_LIST_HEAD(&ei->delayed_iput); init_rwsem(&ei->i_mmap_lock); return inode; } #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS void btrfs_test_destroy_inode(struct inode *inode) { btrfs_drop_extent_map_range(BTRFS_I(inode), 0, (u64)-1, false); kfree(BTRFS_I(inode)->file_extent_tree); kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } #endif void btrfs_free_inode(struct inode *inode) { kfree(BTRFS_I(inode)->file_extent_tree); kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); } void btrfs_destroy_inode(struct inode *vfs_inode) { struct btrfs_ordered_extent *ordered; struct btrfs_inode *inode = BTRFS_I(vfs_inode); struct btrfs_root *root = inode->root; bool freespace_inode; WARN_ON(!hlist_empty(&vfs_inode->i_dentry)); WARN_ON(vfs_inode->i_data.nrpages); WARN_ON(inode->block_rsv.reserved); WARN_ON(inode->block_rsv.size); WARN_ON(inode->outstanding_extents); if (!S_ISDIR(vfs_inode->i_mode)) { WARN_ON(inode->delalloc_bytes); WARN_ON(inode->new_delalloc_bytes); WARN_ON(inode->csum_bytes); } if (!root || !btrfs_is_data_reloc_root(root)) WARN_ON(inode->defrag_bytes); /* * This can happen where we create an inode, but somebody else also * created the same inode and we need to destroy the one we already * created. */ if (!root) return; /* * If this is a free space inode do not take the ordered extents lockdep * map. */ freespace_inode = btrfs_is_free_space_inode(inode); while (1) { ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); if (!ordered) break; else { btrfs_err(root->fs_info, "found ordered extent %llu %llu on inode cleanup", ordered->file_offset, ordered->num_bytes); if (!freespace_inode) btrfs_lockdep_acquire(root->fs_info, btrfs_ordered_extent); btrfs_remove_ordered_extent(inode, ordered); btrfs_put_ordered_extent(ordered); btrfs_put_ordered_extent(ordered); } } btrfs_qgroup_check_reserved_leak(inode); btrfs_del_inode_from_root(inode); btrfs_drop_extent_map_range(inode, 0, (u64)-1, false); btrfs_inode_clear_file_extent_range(inode, 0, (u64)-1); btrfs_put_root(inode->root); } int btrfs_drop_inode(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; if (root == NULL) return 1; /* the snap/subvol tree is on deleting */ if (btrfs_root_refs(&root->root_item) == 0) return 1; else return generic_drop_inode(inode); } static void init_once(void *foo) { struct btrfs_inode *ei = foo; inode_init_once(&ei->vfs_inode); } void __cold btrfs_destroy_cachep(void) { /* * Make sure all delayed rcu free inodes are flushed before we * destroy cache. */ rcu_barrier(); kmem_cache_destroy(btrfs_inode_cachep); } int __init btrfs_init_cachep(void) { btrfs_inode_cachep = kmem_cache_create("btrfs_inode", sizeof(struct btrfs_inode), 0, SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT, init_once); if (!btrfs_inode_cachep) return -ENOMEM; return 0; } static int btrfs_getattr(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags) { u64 delalloc_bytes; u64 inode_bytes; struct inode *inode = d_inode(path->dentry); u32 blocksize = btrfs_sb(inode->i_sb)->sectorsize; u32 bi_flags = BTRFS_I(inode)->flags; u32 bi_ro_flags = BTRFS_I(inode)->ro_flags; stat->result_mask |= STATX_BTIME; stat->btime.tv_sec = BTRFS_I(inode)->i_otime_sec; stat->btime.tv_nsec = BTRFS_I(inode)->i_otime_nsec; if (bi_flags & BTRFS_INODE_APPEND) stat->attributes |= STATX_ATTR_APPEND; if (bi_flags & BTRFS_INODE_COMPRESS) stat->attributes |= STATX_ATTR_COMPRESSED; if (bi_flags & BTRFS_INODE_IMMUTABLE) stat->attributes |= STATX_ATTR_IMMUTABLE; if (bi_flags & BTRFS_INODE_NODUMP) stat->attributes |= STATX_ATTR_NODUMP; if (bi_ro_flags & BTRFS_INODE_RO_VERITY) stat->attributes |= STATX_ATTR_VERITY; stat->attributes_mask |= (STATX_ATTR_APPEND | STATX_ATTR_COMPRESSED | STATX_ATTR_IMMUTABLE | STATX_ATTR_NODUMP); generic_fillattr(idmap, request_mask, inode, stat); stat->dev = BTRFS_I(inode)->root->anon_dev; stat->subvol = BTRFS_I(inode)->root->root_key.objectid; stat->result_mask |= STATX_SUBVOL; spin_lock(&BTRFS_I(inode)->lock); delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes; inode_bytes = inode_get_bytes(inode); spin_unlock(&BTRFS_I(inode)->lock); stat->blocks = (ALIGN(inode_bytes, blocksize) + ALIGN(delalloc_bytes, blocksize)) >> SECTOR_SHIFT; return 0; } static int btrfs_rename_exchange(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { struct btrfs_fs_info *fs_info = inode_to_fs_info(old_dir); struct btrfs_trans_handle *trans; unsigned int trans_num_items; struct btrfs_root *root = BTRFS_I(old_dir)->root; struct btrfs_root *dest = BTRFS_I(new_dir)->root; struct inode *new_inode = new_dentry->d_inode; struct inode *old_inode = old_dentry->d_inode; struct btrfs_rename_ctx old_rename_ctx; struct btrfs_rename_ctx new_rename_ctx; u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); u64 new_ino = btrfs_ino(BTRFS_I(new_inode)); u64 old_idx = 0; u64 new_idx = 0; int ret; int ret2; bool need_abort = false; struct fscrypt_name old_fname, new_fname; struct fscrypt_str *old_name, *new_name; /* * For non-subvolumes allow exchange only within one subvolume, in the * same inode namespace. Two subvolumes (represented as directory) can * be exchanged as they're a logical link and have a fixed inode number. */ if (root != dest && (old_ino != BTRFS_FIRST_FREE_OBJECTID || new_ino != BTRFS_FIRST_FREE_OBJECTID)) return -EXDEV; ret = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_fname); if (ret) return ret; ret = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_fname); if (ret) { fscrypt_free_filename(&old_fname); return ret; } old_name = &old_fname.disk_name; new_name = &new_fname.disk_name; /* close the race window with snapshot create/destroy ioctl */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID || new_ino == BTRFS_FIRST_FREE_OBJECTID) down_read(&fs_info->subvol_sem); /* * For each inode: * 1 to remove old dir item * 1 to remove old dir index * 1 to add new dir item * 1 to add new dir index * 1 to update parent inode * * If the parents are the same, we only need to account for one */ trans_num_items = (old_dir == new_dir ? 9 : 10); if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { /* * 1 to remove old root ref * 1 to remove old root backref * 1 to add new root ref * 1 to add new root backref */ trans_num_items += 4; } else { /* * 1 to update inode item * 1 to remove old inode ref * 1 to add new inode ref */ trans_num_items += 3; } if (new_ino == BTRFS_FIRST_FREE_OBJECTID) trans_num_items += 4; else trans_num_items += 3; trans = btrfs_start_transaction(root, trans_num_items); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_notrans; } if (dest != root) { ret = btrfs_record_root_in_trans(trans, dest); if (ret) goto out_fail; } /* * We need to find a free sequence number both in the source and * in the destination directory for the exchange. */ ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx); if (ret) goto out_fail; ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx); if (ret) goto out_fail; BTRFS_I(old_inode)->dir_index = 0ULL; BTRFS_I(new_inode)->dir_index = 0ULL; /* Reference for the source. */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { /* force full log commit if subvolume involved. */ btrfs_set_log_full_commit(trans); } else { ret = btrfs_insert_inode_ref(trans, dest, new_name, old_ino, btrfs_ino(BTRFS_I(new_dir)), old_idx); if (ret) goto out_fail; need_abort = true; } /* And now for the dest. */ if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { /* force full log commit if subvolume involved. */ btrfs_set_log_full_commit(trans); } else { ret = btrfs_insert_inode_ref(trans, root, old_name, new_ino, btrfs_ino(BTRFS_I(old_dir)), new_idx); if (ret) { if (need_abort) btrfs_abort_transaction(trans, ret); goto out_fail; } } /* Update inode version and ctime/mtime. */ inode_inc_iversion(old_dir); inode_inc_iversion(new_dir); inode_inc_iversion(old_inode); inode_inc_iversion(new_inode); simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry); if (old_dentry->d_parent != new_dentry->d_parent) { btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), BTRFS_I(old_inode), true); btrfs_record_unlink_dir(trans, BTRFS_I(new_dir), BTRFS_I(new_inode), true); } /* src is a subvolume */ if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { ret = btrfs_unlink_subvol(trans, BTRFS_I(old_dir), old_dentry); } else { /* src is an inode */ ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir), BTRFS_I(old_dentry->d_inode), old_name, &old_rename_ctx); if (!ret) ret = btrfs_update_inode(trans, BTRFS_I(old_inode)); } if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } /* dest is a subvolume */ if (new_ino == BTRFS_FIRST_FREE_OBJECTID) { ret = btrfs_unlink_subvol(trans, BTRFS_I(new_dir), new_dentry); } else { /* dest is an inode */ ret = __btrfs_unlink_inode(trans, BTRFS_I(new_dir), BTRFS_I(new_dentry->d_inode), new_name, &new_rename_ctx); if (!ret) ret = btrfs_update_inode(trans, BTRFS_I(new_inode)); } if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), new_name, 0, old_idx); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode), old_name, 0, new_idx); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } if (old_inode->i_nlink == 1) BTRFS_I(old_inode)->dir_index = old_idx; if (new_inode->i_nlink == 1) BTRFS_I(new_inode)->dir_index = new_idx; /* * Now pin the logs of the roots. We do it to ensure that no other task * can sync the logs while we are in progress with the rename, because * that could result in an inconsistency in case any of the inodes that * are part of this rename operation were logged before. */ if (old_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_pin_log_trans(root); if (new_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_pin_log_trans(dest); /* Do the log updates for all inodes. */ if (old_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_log_new_name(trans, old_dentry, BTRFS_I(old_dir), old_rename_ctx.index, new_dentry->d_parent); if (new_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_log_new_name(trans, new_dentry, BTRFS_I(new_dir), new_rename_ctx.index, old_dentry->d_parent); /* Now unpin the logs. */ if (old_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_end_log_trans(root); if (new_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_end_log_trans(dest); out_fail: ret2 = btrfs_end_transaction(trans); ret = ret ? ret : ret2; out_notrans: if (new_ino == BTRFS_FIRST_FREE_OBJECTID || old_ino == BTRFS_FIRST_FREE_OBJECTID) up_read(&fs_info->subvol_sem); fscrypt_free_filename(&new_fname); fscrypt_free_filename(&old_fname); return ret; } static struct inode *new_whiteout_inode(struct mnt_idmap *idmap, struct inode *dir) { struct inode *inode; inode = new_inode(dir->i_sb); if (inode) { inode_init_owner(idmap, inode, dir, S_IFCHR | WHITEOUT_MODE); inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, WHITEOUT_DEV); } return inode; } static int btrfs_rename(struct mnt_idmap *idmap, struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { struct btrfs_fs_info *fs_info = inode_to_fs_info(old_dir); struct btrfs_new_inode_args whiteout_args = { .dir = old_dir, .dentry = old_dentry, }; struct btrfs_trans_handle *trans; unsigned int trans_num_items; struct btrfs_root *root = BTRFS_I(old_dir)->root; struct btrfs_root *dest = BTRFS_I(new_dir)->root; struct inode *new_inode = d_inode(new_dentry); struct inode *old_inode = d_inode(old_dentry); struct btrfs_rename_ctx rename_ctx; u64 index = 0; int ret; int ret2; u64 old_ino = btrfs_ino(BTRFS_I(old_inode)); struct fscrypt_name old_fname, new_fname; if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) return -EPERM; /* we only allow rename subvolume link between subvolumes */ if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) return -EXDEV; if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID)) return -ENOTEMPTY; if (S_ISDIR(old_inode->i_mode) && new_inode && new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) return -ENOTEMPTY; ret = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_fname); if (ret) return ret; ret = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_fname); if (ret) { fscrypt_free_filename(&old_fname); return ret; } /* check for collisions, even if the name isn't there */ ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino, &new_fname.disk_name); if (ret) { if (ret == -EEXIST) { /* we shouldn't get * eexist without a new_inode */ if (WARN_ON(!new_inode)) { goto out_fscrypt_names; } } else { /* maybe -EOVERFLOW */ goto out_fscrypt_names; } } ret = 0; /* * we're using rename to replace one file with another. Start IO on it * now so we don't add too much work to the end of the transaction */ if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size) filemap_flush(old_inode->i_mapping); if (flags & RENAME_WHITEOUT) { whiteout_args.inode = new_whiteout_inode(idmap, old_dir); if (!whiteout_args.inode) { ret = -ENOMEM; goto out_fscrypt_names; } ret = btrfs_new_inode_prepare(&whiteout_args, &trans_num_items); if (ret) goto out_whiteout_inode; } else { /* 1 to update the old parent inode. */ trans_num_items = 1; } if (old_ino == BTRFS_FIRST_FREE_OBJECTID) { /* Close the race window with snapshot create/destroy ioctl */ down_read(&fs_info->subvol_sem); /* * 1 to remove old root ref * 1 to remove old root backref * 1 to add new root ref * 1 to add new root backref */ trans_num_items += 4; } else { /* * 1 to update inode * 1 to remove old inode ref * 1 to add new inode ref */ trans_num_items += 3; } /* * 1 to remove old dir item * 1 to remove old dir index * 1 to add new dir item * 1 to add new dir index */ trans_num_items += 4; /* 1 to update new parent inode if it's not the same as the old parent */ if (new_dir != old_dir) trans_num_items++; if (new_inode) { /* * 1 to update inode * 1 to remove inode ref * 1 to remove dir item * 1 to remove dir index * 1 to possibly add orphan item */ trans_num_items += 5; } trans = btrfs_start_transaction(root, trans_num_items); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_notrans; } if (dest != root) { ret = btrfs_record_root_in_trans(trans, dest); if (ret) goto out_fail; } ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index); if (ret) goto out_fail; BTRFS_I(old_inode)->dir_index = 0ULL; if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { /* force full log commit if subvolume involved. */ btrfs_set_log_full_commit(trans); } else { ret = btrfs_insert_inode_ref(trans, dest, &new_fname.disk_name, old_ino, btrfs_ino(BTRFS_I(new_dir)), index); if (ret) goto out_fail; } inode_inc_iversion(old_dir); inode_inc_iversion(new_dir); inode_inc_iversion(old_inode); simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry); if (old_dentry->d_parent != new_dentry->d_parent) btrfs_record_unlink_dir(trans, BTRFS_I(old_dir), BTRFS_I(old_inode), true); if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { ret = btrfs_unlink_subvol(trans, BTRFS_I(old_dir), old_dentry); } else { ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir), BTRFS_I(d_inode(old_dentry)), &old_fname.disk_name, &rename_ctx); if (!ret) ret = btrfs_update_inode(trans, BTRFS_I(old_inode)); } if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } if (new_inode) { inode_inc_iversion(new_inode); if (unlikely(btrfs_ino(BTRFS_I(new_inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { ret = btrfs_unlink_subvol(trans, BTRFS_I(new_dir), new_dentry); BUG_ON(new_inode->i_nlink == 0); } else { ret = btrfs_unlink_inode(trans, BTRFS_I(new_dir), BTRFS_I(d_inode(new_dentry)), &new_fname.disk_name); } if (!ret && new_inode->i_nlink == 0) ret = btrfs_orphan_add(trans, BTRFS_I(d_inode(new_dentry))); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } } ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode), &new_fname.disk_name, 0, index); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } if (old_inode->i_nlink == 1) BTRFS_I(old_inode)->dir_index = index; if (old_ino != BTRFS_FIRST_FREE_OBJECTID) btrfs_log_new_name(trans, old_dentry, BTRFS_I(old_dir), rename_ctx.index, new_dentry->d_parent); if (flags & RENAME_WHITEOUT) { ret = btrfs_create_new_inode(trans, &whiteout_args); if (ret) { btrfs_abort_transaction(trans, ret); goto out_fail; } else { unlock_new_inode(whiteout_args.inode); iput(whiteout_args.inode); whiteout_args.inode = NULL; } } out_fail: ret2 = btrfs_end_transaction(trans); ret = ret ? ret : ret2; out_notrans: if (old_ino == BTRFS_FIRST_FREE_OBJECTID) up_read(&fs_info->subvol_sem); if (flags & RENAME_WHITEOUT) btrfs_new_inode_args_destroy(&whiteout_args); out_whiteout_inode: if (flags & RENAME_WHITEOUT) iput(whiteout_args.inode); out_fscrypt_names: fscrypt_free_filename(&old_fname); fscrypt_free_filename(&new_fname); return ret; } static int btrfs_rename2(struct mnt_idmap *idmap, struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { int ret; if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) return -EINVAL; if (flags & RENAME_EXCHANGE) ret = btrfs_rename_exchange(old_dir, old_dentry, new_dir, new_dentry); else ret = btrfs_rename(idmap, old_dir, old_dentry, new_dir, new_dentry, flags); btrfs_btree_balance_dirty(BTRFS_I(new_dir)->root->fs_info); return ret; } struct btrfs_delalloc_work { struct inode *inode; struct completion completion; struct list_head list; struct btrfs_work work; }; static void btrfs_run_delalloc_work(struct btrfs_work *work) { struct btrfs_delalloc_work *delalloc_work; struct inode *inode; delalloc_work = container_of(work, struct btrfs_delalloc_work, work); inode = delalloc_work->inode; filemap_flush(inode->i_mapping); if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &BTRFS_I(inode)->runtime_flags)) filemap_flush(inode->i_mapping); iput(inode); complete(&delalloc_work->completion); } static struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode) { struct btrfs_delalloc_work *work; work = kmalloc(sizeof(*work), GFP_NOFS); if (!work) return NULL; init_completion(&work->completion); INIT_LIST_HEAD(&work->list); work->inode = inode; btrfs_init_work(&work->work, btrfs_run_delalloc_work, NULL); return work; } /* * some fairly slow code that needs optimization. This walks the list * of all the inodes with pending delalloc and forces them to disk. */ static int start_delalloc_inodes(struct btrfs_root *root, struct writeback_control *wbc, bool snapshot, bool in_reclaim_context) { struct btrfs_inode *binode; struct inode *inode; struct btrfs_delalloc_work *work, *next; LIST_HEAD(works); LIST_HEAD(splice); int ret = 0; bool full_flush = wbc->nr_to_write == LONG_MAX; mutex_lock(&root->delalloc_mutex); spin_lock(&root->delalloc_lock); list_splice_init(&root->delalloc_inodes, &splice); while (!list_empty(&splice)) { binode = list_entry(splice.next, struct btrfs_inode, delalloc_inodes); list_move_tail(&binode->delalloc_inodes, &root->delalloc_inodes); if (in_reclaim_context && test_bit(BTRFS_INODE_NO_DELALLOC_FLUSH, &binode->runtime_flags)) continue; inode = igrab(&binode->vfs_inode); if (!inode) { cond_resched_lock(&root->delalloc_lock); continue; } spin_unlock(&root->delalloc_lock); if (snapshot) set_bit(BTRFS_INODE_SNAPSHOT_FLUSH, &binode->runtime_flags); if (full_flush) { work = btrfs_alloc_delalloc_work(inode); if (!work) { iput(inode); ret = -ENOMEM; goto out; } list_add_tail(&work->list, &works); btrfs_queue_work(root->fs_info->flush_workers, &work->work); } else { ret = filemap_fdatawrite_wbc(inode->i_mapping, wbc); btrfs_add_delayed_iput(BTRFS_I(inode)); if (ret || wbc->nr_to_write <= 0) goto out; } cond_resched(); spin_lock(&root->delalloc_lock); } spin_unlock(&root->delalloc_lock); out: list_for_each_entry_safe(work, next, &works, list) { list_del_init(&work->list); wait_for_completion(&work->completion); kfree(work); } if (!list_empty(&splice)) { spin_lock(&root->delalloc_lock); list_splice_tail(&splice, &root->delalloc_inodes); spin_unlock(&root->delalloc_lock); } mutex_unlock(&root->delalloc_mutex); return ret; } int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_context) { struct writeback_control wbc = { .nr_to_write = LONG_MAX, .sync_mode = WB_SYNC_NONE, .range_start = 0, .range_end = LLONG_MAX, }; struct btrfs_fs_info *fs_info = root->fs_info; if (BTRFS_FS_ERROR(fs_info)) return -EROFS; return start_delalloc_inodes(root, &wbc, true, in_reclaim_context); } int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr, bool in_reclaim_context) { struct writeback_control wbc = { .nr_to_write = nr, .sync_mode = WB_SYNC_NONE, .range_start = 0, .range_end = LLONG_MAX, }; struct btrfs_root *root; LIST_HEAD(splice); int ret; if (BTRFS_FS_ERROR(fs_info)) return -EROFS; mutex_lock(&fs_info->delalloc_root_mutex); spin_lock(&fs_info->delalloc_root_lock); list_splice_init(&fs_info->delalloc_roots, &splice); while (!list_empty(&splice)) { /* * Reset nr_to_write here so we know that we're doing a full * flush. */ if (nr == LONG_MAX) wbc.nr_to_write = LONG_MAX; root = list_first_entry(&splice, struct btrfs_root, delalloc_root); root = btrfs_grab_root(root); BUG_ON(!root); list_move_tail(&root->delalloc_root, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); ret = start_delalloc_inodes(root, &wbc, false, in_reclaim_context); btrfs_put_root(root); if (ret < 0 || wbc.nr_to_write <= 0) goto out; spin_lock(&fs_info->delalloc_root_lock); } spin_unlock(&fs_info->delalloc_root_lock); ret = 0; out: if (!list_empty(&splice)) { spin_lock(&fs_info->delalloc_root_lock); list_splice_tail(&splice, &fs_info->delalloc_roots); spin_unlock(&fs_info->delalloc_root_lock); } mutex_unlock(&fs_info->delalloc_root_mutex); return ret; } static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir, struct dentry *dentry, const char *symname) { struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; struct btrfs_path *path; struct btrfs_key key; struct inode *inode; struct btrfs_new_inode_args new_inode_args = { .dir = dir, .dentry = dentry, }; unsigned int trans_num_items; int err; int name_len; int datasize; unsigned long ptr; struct btrfs_file_extent_item *ei; struct extent_buffer *leaf; name_len = strlen(symname); if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info)) return -ENAMETOOLONG; inode = new_inode(dir->i_sb); if (!inode) return -ENOMEM; inode_init_owner(idmap, inode, dir, S_IFLNK | S_IRWXUGO); inode->i_op = &btrfs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_aops; btrfs_i_size_write(BTRFS_I(inode), name_len); inode_set_bytes(inode, name_len); new_inode_args.inode = inode; err = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items); if (err) goto out_inode; /* 1 additional item for the inline extent */ trans_num_items++; trans = btrfs_start_transaction(root, trans_num_items); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_new_inode_args; } err = btrfs_create_new_inode(trans, &new_inode_args); if (err) goto out; path = btrfs_alloc_path(); if (!path) { err = -ENOMEM; btrfs_abort_transaction(trans, err); discard_new_inode(inode); inode = NULL; goto out; } key.objectid = btrfs_ino(BTRFS_I(inode)); key.offset = 0; key.type = BTRFS_EXTENT_DATA_KEY; datasize = btrfs_file_extent_calc_inline_size(name_len); err = btrfs_insert_empty_item(trans, root, path, &key, datasize); if (err) { btrfs_abort_transaction(trans, err); btrfs_free_path(path); discard_new_inode(inode); inode = NULL; goto out; } leaf = path->nodes[0]; ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, ei, trans->transid); btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); btrfs_set_file_extent_encryption(leaf, ei, 0); btrfs_set_file_extent_compression(leaf, ei, 0); btrfs_set_file_extent_other_encoding(leaf, ei, 0); btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); ptr = btrfs_file_extent_inline_start(ei); write_extent_buffer(leaf, symname, ptr, name_len); btrfs_mark_buffer_dirty(trans, leaf); btrfs_free_path(path); d_instantiate_new(dentry, inode); err = 0; out: btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); out_new_inode_args: btrfs_new_inode_args_destroy(&new_inode_args); out_inode: if (err) iput(inode); return err; } static struct btrfs_trans_handle *insert_prealloc_file_extent( struct btrfs_trans_handle *trans_in, struct btrfs_inode *inode, struct btrfs_key *ins, u64 file_offset) { struct btrfs_file_extent_item stack_fi; struct btrfs_replace_extent_info extent_info; struct btrfs_trans_handle *trans = trans_in; struct btrfs_path *path; u64 start = ins->objectid; u64 len = ins->offset; u64 qgroup_released = 0; int ret; memset(&stack_fi, 0, sizeof(stack_fi)); btrfs_set_stack_file_extent_type(&stack_fi, BTRFS_FILE_EXTENT_PREALLOC); btrfs_set_stack_file_extent_disk_bytenr(&stack_fi, start); btrfs_set_stack_file_extent_disk_num_bytes(&stack_fi, len); btrfs_set_stack_file_extent_num_bytes(&stack_fi, len); btrfs_set_stack_file_extent_ram_bytes(&stack_fi, len); btrfs_set_stack_file_extent_compression(&stack_fi, BTRFS_COMPRESS_NONE); /* Encryption and other encoding is reserved and all 0 */ ret = btrfs_qgroup_release_data(inode, file_offset, len, &qgroup_released); if (ret < 0) return ERR_PTR(ret); if (trans) { ret = insert_reserved_file_extent(trans, inode, file_offset, &stack_fi, true, qgroup_released); if (ret) goto free_qgroup; return trans; } extent_info.disk_offset = start; extent_info.disk_len = len; extent_info.data_offset = 0; extent_info.data_len = len; extent_info.file_offset = file_offset; extent_info.extent_buf = (char *)&stack_fi; extent_info.is_new_extent = true; extent_info.update_times = true; extent_info.qgroup_reserved = qgroup_released; extent_info.insertions = 0; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto free_qgroup; } ret = btrfs_replace_file_extents(inode, path, file_offset, file_offset + len - 1, &extent_info, &trans); btrfs_free_path(path); if (ret) goto free_qgroup; return trans; free_qgroup: /* * We have released qgroup data range at the beginning of the function, * and normally qgroup_released bytes will be freed when committing * transaction. * But if we error out early, we have to free what we have released * or we leak qgroup data reservation. */ btrfs_qgroup_free_refroot(inode->root->fs_info, btrfs_root_id(inode->root), qgroup_released, BTRFS_QGROUP_RSV_DATA); return ERR_PTR(ret); } static int __btrfs_prealloc_file_range(struct inode *inode, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint, struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); struct extent_map *em; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key ins; u64 cur_offset = start; u64 clear_offset = start; u64 i_size; u64 cur_bytes; u64 last_alloc = (u64)-1; int ret = 0; bool own_trans = true; u64 end = start + num_bytes - 1; if (trans) own_trans = false; while (num_bytes > 0) { cur_bytes = min_t(u64, num_bytes, SZ_256M); cur_bytes = max(cur_bytes, min_size); /* * If we are severely fragmented we could end up with really * small allocations, so if the allocator is returning small * chunks lets make its job easier by only searching for those * sized chunks. */ cur_bytes = min(cur_bytes, last_alloc); ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes, min_size, 0, *alloc_hint, &ins, 1, 0); if (ret) break; /* * We've reserved this space, and thus converted it from * ->bytes_may_use to ->bytes_reserved. Any error that happens * from here on out we will only need to clear our reservation * for the remaining unreserved area, so advance our * clear_offset by our extent size. */ clear_offset += ins.offset; last_alloc = ins.offset; trans = insert_prealloc_file_extent(trans, BTRFS_I(inode), &ins, cur_offset); /* * Now that we inserted the prealloc extent we can finally * decrement the number of reservations in the block group. * If we did it before, we could race with relocation and have * relocation miss the reserved extent, making it fail later. */ btrfs_dec_block_group_reservations(fs_info, ins.objectid); if (IS_ERR(trans)) { ret = PTR_ERR(trans); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 0); break; } em = alloc_extent_map(); if (!em) { btrfs_drop_extent_map_range(BTRFS_I(inode), cur_offset, cur_offset + ins.offset - 1, false); btrfs_set_inode_full_sync(BTRFS_I(inode)); goto next; } em->start = cur_offset; em->len = ins.offset; em->disk_bytenr = ins.objectid; em->offset = 0; em->disk_num_bytes = ins.offset; em->ram_bytes = ins.offset; em->flags |= EXTENT_FLAG_PREALLOC; em->generation = trans->transid; ret = btrfs_replace_extent_map_range(BTRFS_I(inode), em, true); free_extent_map(em); next: num_bytes -= ins.offset; cur_offset += ins.offset; *alloc_hint = ins.objectid + ins.offset; inode_inc_iversion(inode); inode_set_ctime_current(inode); BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; if (!(mode & FALLOC_FL_KEEP_SIZE) && (actual_len > inode->i_size) && (cur_offset > inode->i_size)) { if (cur_offset > actual_len) i_size = actual_len; else i_size = cur_offset; i_size_write(inode, i_size); btrfs_inode_safe_disk_i_size_write(BTRFS_I(inode), 0); } ret = btrfs_update_inode(trans, BTRFS_I(inode)); if (ret) { btrfs_abort_transaction(trans, ret); if (own_trans) btrfs_end_transaction(trans); break; } if (own_trans) { btrfs_end_transaction(trans); trans = NULL; } } if (clear_offset < end) btrfs_free_reserved_data_space(BTRFS_I(inode), NULL, clear_offset, end - clear_offset + 1); return ret; } int btrfs_prealloc_file_range(struct inode *inode, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint) { return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, min_size, actual_len, alloc_hint, NULL); } int btrfs_prealloc_file_range_trans(struct inode *inode, struct btrfs_trans_handle *trans, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint) { return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, min_size, actual_len, alloc_hint, trans); } static int btrfs_permission(struct mnt_idmap *idmap, struct inode *inode, int mask) { struct btrfs_root *root = BTRFS_I(inode)->root; umode_t mode = inode->i_mode; if (mask & MAY_WRITE && (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { if (btrfs_root_readonly(root)) return -EROFS; if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) return -EACCES; } return generic_permission(idmap, inode, mask); } static int btrfs_tmpfile(struct mnt_idmap *idmap, struct inode *dir, struct file *file, umode_t mode) { struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(dir)->root; struct inode *inode; struct btrfs_new_inode_args new_inode_args = { .dir = dir, .dentry = file->f_path.dentry, .orphan = true, }; unsigned int trans_num_items; int ret; inode = new_inode(dir->i_sb); if (!inode) return -ENOMEM; inode_init_owner(idmap, inode, dir, mode); inode->i_fop = &btrfs_file_operations; inode->i_op = &btrfs_file_inode_operations; inode->i_mapping->a_ops = &btrfs_aops; new_inode_args.inode = inode; ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items); if (ret) goto out_inode; trans = btrfs_start_transaction(root, trans_num_items); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out_new_inode_args; } ret = btrfs_create_new_inode(trans, &new_inode_args); /* * We set number of links to 0 in btrfs_create_new_inode(), and here we * set it to 1 because d_tmpfile() will issue a warning if the count is * 0, through: * * d_tmpfile() -> inode_dec_link_count() -> drop_nlink() */ set_nlink(inode, 1); if (!ret) { d_tmpfile(file, inode); unlock_new_inode(inode); mark_inode_dirty(inode); } btrfs_end_transaction(trans); btrfs_btree_balance_dirty(fs_info); out_new_inode_args: btrfs_new_inode_args_destroy(&new_inode_args); out_inode: if (ret) iput(inode); return finish_open_simple(file, ret); } void btrfs_set_range_writeback(struct btrfs_inode *inode, u64 start, u64 end) { struct btrfs_fs_info *fs_info = inode->root->fs_info; unsigned long index = start >> PAGE_SHIFT; unsigned long end_index = end >> PAGE_SHIFT; struct folio *folio; u32 len; ASSERT(end + 1 - start <= U32_MAX); len = end + 1 - start; while (index <= end_index) { folio = __filemap_get_folio(inode->vfs_inode.i_mapping, index, 0, 0); ASSERT(!IS_ERR(folio)); /* folios should be in the extent_io_tree */ /* This is for data, which doesn't yet support larger folio. */ ASSERT(folio_order(folio) == 0); btrfs_folio_set_writeback(fs_info, folio, start, len); folio_put(folio); index++; } } int btrfs_encoded_io_compression_from_extent(struct btrfs_fs_info *fs_info, int compress_type) { switch (compress_type) { case BTRFS_COMPRESS_NONE: return BTRFS_ENCODED_IO_COMPRESSION_NONE; case BTRFS_COMPRESS_ZLIB: return BTRFS_ENCODED_IO_COMPRESSION_ZLIB; case BTRFS_COMPRESS_LZO: /* * The LZO format depends on the sector size. 64K is the maximum * sector size that we support. */ if (fs_info->sectorsize < SZ_4K || fs_info->sectorsize > SZ_64K) return -EINVAL; return BTRFS_ENCODED_IO_COMPRESSION_LZO_4K + (fs_info->sectorsize_bits - 12); case BTRFS_COMPRESS_ZSTD: return BTRFS_ENCODED_IO_COMPRESSION_ZSTD; default: return -EUCLEAN; } } static ssize_t btrfs_encoded_read_inline( struct kiocb *iocb, struct iov_iter *iter, u64 start, u64 lockend, struct extent_state **cached_state, u64 extent_start, size_t count, struct btrfs_ioctl_encoded_io_args *encoded, bool *unlocked) { struct btrfs_inode *inode = BTRFS_I(file_inode(iocb->ki_filp)); struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct extent_io_tree *io_tree = &inode->io_tree; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_file_extent_item *item; u64 ram_bytes; unsigned long ptr; void *tmp; ssize_t ret; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(inode), extent_start, 0); if (ret) { if (ret > 0) { /* The extent item disappeared? */ ret = -EIO; } goto out; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); ram_bytes = btrfs_file_extent_ram_bytes(leaf, item); ptr = btrfs_file_extent_inline_start(item); encoded->len = min_t(u64, extent_start + ram_bytes, inode->vfs_inode.i_size) - iocb->ki_pos; ret = btrfs_encoded_io_compression_from_extent(fs_info, btrfs_file_extent_compression(leaf, item)); if (ret < 0) goto out; encoded->compression = ret; if (encoded->compression) { size_t inline_size; inline_size = btrfs_file_extent_inline_item_len(leaf, path->slots[0]); if (inline_size > count) { ret = -ENOBUFS; goto out; } count = inline_size; encoded->unencoded_len = ram_bytes; encoded->unencoded_offset = iocb->ki_pos - extent_start; } else { count = min_t(u64, count, encoded->len); encoded->len = count; encoded->unencoded_len = count; ptr += iocb->ki_pos - extent_start; } tmp = kmalloc(count, GFP_NOFS); if (!tmp) { ret = -ENOMEM; goto out; } read_extent_buffer(leaf, tmp, ptr, count); btrfs_release_path(path); unlock_extent(io_tree, start, lockend, cached_state); btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); *unlocked = true; ret = copy_to_iter(tmp, count, iter); if (ret != count) ret = -EFAULT; kfree(tmp); out: btrfs_free_path(path); return ret; } struct btrfs_encoded_read_private { wait_queue_head_t wait; atomic_t pending; blk_status_t status; }; static void btrfs_encoded_read_endio(struct btrfs_bio *bbio) { struct btrfs_encoded_read_private *priv = bbio->private; if (bbio->bio.bi_status) { /* * The memory barrier implied by the atomic_dec_return() here * pairs with the memory barrier implied by the * atomic_dec_return() or io_wait_event() in * btrfs_encoded_read_regular_fill_pages() to ensure that this * write is observed before the load of status in * btrfs_encoded_read_regular_fill_pages(). */ WRITE_ONCE(priv->status, bbio->bio.bi_status); } if (!atomic_dec_return(&priv->pending)) wake_up(&priv->wait); bio_put(&bbio->bio); } int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode, u64 file_offset, u64 disk_bytenr, u64 disk_io_size, struct page **pages) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct btrfs_encoded_read_private priv = { .pending = ATOMIC_INIT(1), }; unsigned long i = 0; struct btrfs_bio *bbio; init_waitqueue_head(&priv.wait); bbio = btrfs_bio_alloc(BIO_MAX_VECS, REQ_OP_READ, fs_info, btrfs_encoded_read_endio, &priv); bbio->bio.bi_iter.bi_sector = disk_bytenr >> SECTOR_SHIFT; bbio->inode = inode; do { size_t bytes = min_t(u64, disk_io_size, PAGE_SIZE); if (bio_add_page(&bbio->bio, pages[i], bytes, 0) < bytes) { atomic_inc(&priv.pending); btrfs_submit_bbio(bbio, 0); bbio = btrfs_bio_alloc(BIO_MAX_VECS, REQ_OP_READ, fs_info, btrfs_encoded_read_endio, &priv); bbio->bio.bi_iter.bi_sector = disk_bytenr >> SECTOR_SHIFT; bbio->inode = inode; continue; } i++; disk_bytenr += bytes; disk_io_size -= bytes; } while (disk_io_size); atomic_inc(&priv.pending); btrfs_submit_bbio(bbio, 0); if (atomic_dec_return(&priv.pending)) io_wait_event(priv.wait, !atomic_read(&priv.pending)); /* See btrfs_encoded_read_endio() for ordering. */ return blk_status_to_errno(READ_ONCE(priv.status)); } static ssize_t btrfs_encoded_read_regular(struct kiocb *iocb, struct iov_iter *iter, u64 start, u64 lockend, struct extent_state **cached_state, u64 disk_bytenr, u64 disk_io_size, size_t count, bool compressed, bool *unlocked) { struct btrfs_inode *inode = BTRFS_I(file_inode(iocb->ki_filp)); struct extent_io_tree *io_tree = &inode->io_tree; struct page **pages; unsigned long nr_pages, i; u64 cur; size_t page_offset; ssize_t ret; nr_pages = DIV_ROUND_UP(disk_io_size, PAGE_SIZE); pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); if (!pages) return -ENOMEM; ret = btrfs_alloc_page_array(nr_pages, pages, false); if (ret) { ret = -ENOMEM; goto out; } ret = btrfs_encoded_read_regular_fill_pages(inode, start, disk_bytenr, disk_io_size, pages); if (ret) goto out; unlock_extent(io_tree, start, lockend, cached_state); btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); *unlocked = true; if (compressed) { i = 0; page_offset = 0; } else { i = (iocb->ki_pos - start) >> PAGE_SHIFT; page_offset = (iocb->ki_pos - start) & (PAGE_SIZE - 1); } cur = 0; while (cur < count) { size_t bytes = min_t(size_t, count - cur, PAGE_SIZE - page_offset); if (copy_page_to_iter(pages[i], page_offset, bytes, iter) != bytes) { ret = -EFAULT; goto out; } i++; cur += bytes; page_offset = 0; } ret = count; out: for (i = 0; i < nr_pages; i++) { if (pages[i]) __free_page(pages[i]); } kfree(pages); return ret; } ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter, struct btrfs_ioctl_encoded_io_args *encoded) { struct btrfs_inode *inode = BTRFS_I(file_inode(iocb->ki_filp)); struct btrfs_fs_info *fs_info = inode->root->fs_info; struct extent_io_tree *io_tree = &inode->io_tree; ssize_t ret; size_t count = iov_iter_count(iter); u64 start, lockend, disk_bytenr, disk_io_size; struct extent_state *cached_state = NULL; struct extent_map *em; bool unlocked = false; file_accessed(iocb->ki_filp); btrfs_inode_lock(inode, BTRFS_ILOCK_SHARED); if (iocb->ki_pos >= inode->vfs_inode.i_size) { btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); return 0; } start = ALIGN_DOWN(iocb->ki_pos, fs_info->sectorsize); /* * We don't know how long the extent containing iocb->ki_pos is, but if * it's compressed we know that it won't be longer than this. */ lockend = start + BTRFS_MAX_UNCOMPRESSED - 1; for (;;) { struct btrfs_ordered_extent *ordered; ret = btrfs_wait_ordered_range(inode, start, lockend - start + 1); if (ret) goto out_unlock_inode; lock_extent(io_tree, start, lockend, &cached_state); ordered = btrfs_lookup_ordered_range(inode, start, lockend - start + 1); if (!ordered) break; btrfs_put_ordered_extent(ordered); unlock_extent(io_tree, start, lockend, &cached_state); cond_resched(); } em = btrfs_get_extent(inode, NULL, start, lockend - start + 1); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out_unlock_extent; } if (em->disk_bytenr == EXTENT_MAP_INLINE) { u64 extent_start = em->start; /* * For inline extents we get everything we need out of the * extent item. */ free_extent_map(em); em = NULL; ret = btrfs_encoded_read_inline(iocb, iter, start, lockend, &cached_state, extent_start, count, encoded, &unlocked); goto out; } /* * We only want to return up to EOF even if the extent extends beyond * that. */ encoded->len = min_t(u64, extent_map_end(em), inode->vfs_inode.i_size) - iocb->ki_pos; if (em->disk_bytenr == EXTENT_MAP_HOLE || (em->flags & EXTENT_FLAG_PREALLOC)) { disk_bytenr = EXTENT_MAP_HOLE; count = min_t(u64, count, encoded->len); encoded->len = count; encoded->unencoded_len = count; } else if (extent_map_is_compressed(em)) { disk_bytenr = em->disk_bytenr; /* * Bail if the buffer isn't large enough to return the whole * compressed extent. */ if (em->disk_num_bytes > count) { ret = -ENOBUFS; goto out_em; } disk_io_size = em->disk_num_bytes; count = em->disk_num_bytes; encoded->unencoded_len = em->ram_bytes; encoded->unencoded_offset = iocb->ki_pos - (em->start - em->offset); ret = btrfs_encoded_io_compression_from_extent(fs_info, extent_map_compression(em)); if (ret < 0) goto out_em; encoded->compression = ret; } else { disk_bytenr = extent_map_block_start(em) + (start - em->start); if (encoded->len > count) encoded->len = count; /* * Don't read beyond what we locked. This also limits the page * allocations that we'll do. */ disk_io_size = min(lockend + 1, iocb->ki_pos + encoded->len) - start; count = start + disk_io_size - iocb->ki_pos; encoded->len = count; encoded->unencoded_len = count; disk_io_size = ALIGN(disk_io_size, fs_info->sectorsize); } free_extent_map(em); em = NULL; if (disk_bytenr == EXTENT_MAP_HOLE) { unlock_extent(io_tree, start, lockend, &cached_state); btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); unlocked = true; ret = iov_iter_zero(count, iter); if (ret != count) ret = -EFAULT; } else { ret = btrfs_encoded_read_regular(iocb, iter, start, lockend, &cached_state, disk_bytenr, disk_io_size, count, encoded->compression, &unlocked); } out: if (ret >= 0) iocb->ki_pos += encoded->len; out_em: free_extent_map(em); out_unlock_extent: if (!unlocked) unlock_extent(io_tree, start, lockend, &cached_state); out_unlock_inode: if (!unlocked) btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); return ret; } ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from, const struct btrfs_ioctl_encoded_io_args *encoded) { struct btrfs_inode *inode = BTRFS_I(file_inode(iocb->ki_filp)); struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct extent_io_tree *io_tree = &inode->io_tree; struct extent_changeset *data_reserved = NULL; struct extent_state *cached_state = NULL; struct btrfs_ordered_extent *ordered; struct btrfs_file_extent file_extent; int compression; size_t orig_count; u64 start, end; u64 num_bytes, ram_bytes, disk_num_bytes; unsigned long nr_folios, i; struct folio **folios; struct btrfs_key ins; bool extent_reserved = false; struct extent_map *em; ssize_t ret; switch (encoded->compression) { case BTRFS_ENCODED_IO_COMPRESSION_ZLIB: compression = BTRFS_COMPRESS_ZLIB; break; case BTRFS_ENCODED_IO_COMPRESSION_ZSTD: compression = BTRFS_COMPRESS_ZSTD; break; case BTRFS_ENCODED_IO_COMPRESSION_LZO_4K: case BTRFS_ENCODED_IO_COMPRESSION_LZO_8K: case BTRFS_ENCODED_IO_COMPRESSION_LZO_16K: case BTRFS_ENCODED_IO_COMPRESSION_LZO_32K: case BTRFS_ENCODED_IO_COMPRESSION_LZO_64K: /* The sector size must match for LZO. */ if (encoded->compression - BTRFS_ENCODED_IO_COMPRESSION_LZO_4K + 12 != fs_info->sectorsize_bits) return -EINVAL; compression = BTRFS_COMPRESS_LZO; break; default: return -EINVAL; } if (encoded->encryption != BTRFS_ENCODED_IO_ENCRYPTION_NONE) return -EINVAL; /* * Compressed extents should always have checksums, so error out if we * have a NOCOW file or inode was created while mounted with NODATASUM. */ if (inode->flags & BTRFS_INODE_NODATASUM) return -EINVAL; orig_count = iov_iter_count(from); /* The extent size must be sane. */ if (encoded->unencoded_len > BTRFS_MAX_UNCOMPRESSED || orig_count > BTRFS_MAX_COMPRESSED || orig_count == 0) return -EINVAL; /* * The compressed data must be smaller than the decompressed data. * * It's of course possible for data to compress to larger or the same * size, but the buffered I/O path falls back to no compression for such * data, and we don't want to break any assumptions by creating these * extents. * * Note that this is less strict than the current check we have that the * compressed data must be at least one sector smaller than the * decompressed data. We only want to enforce the weaker requirement * from old kernels that it is at least one byte smaller. */ if (orig_count >= encoded->unencoded_len) return -EINVAL; /* The extent must start on a sector boundary. */ start = iocb->ki_pos; if (!IS_ALIGNED(start, fs_info->sectorsize)) return -EINVAL; /* * The extent must end on a sector boundary. However, we allow a write * which ends at or extends i_size to have an unaligned length; we round * up the extent size and set i_size to the unaligned end. */ if (start + encoded->len < inode->vfs_inode.i_size && !IS_ALIGNED(start + encoded->len, fs_info->sectorsize)) return -EINVAL; /* Finally, the offset in the unencoded data must be sector-aligned. */ if (!IS_ALIGNED(encoded->unencoded_offset, fs_info->sectorsize)) return -EINVAL; num_bytes = ALIGN(encoded->len, fs_info->sectorsize); ram_bytes = ALIGN(encoded->unencoded_len, fs_info->sectorsize); end = start + num_bytes - 1; /* * If the extent cannot be inline, the compressed data on disk must be * sector-aligned. For convenience, we extend it with zeroes if it * isn't. */ disk_num_bytes = ALIGN(orig_count, fs_info->sectorsize); nr_folios = DIV_ROUND_UP(disk_num_bytes, PAGE_SIZE); folios = kvcalloc(nr_folios, sizeof(struct page *), GFP_KERNEL_ACCOUNT); if (!folios) return -ENOMEM; for (i = 0; i < nr_folios; i++) { size_t bytes = min_t(size_t, PAGE_SIZE, iov_iter_count(from)); char *kaddr; folios[i] = folio_alloc(GFP_KERNEL_ACCOUNT, 0); if (!folios[i]) { ret = -ENOMEM; goto out_folios; } kaddr = kmap_local_folio(folios[i], 0); if (copy_from_iter(kaddr, bytes, from) != bytes) { kunmap_local(kaddr); ret = -EFAULT; goto out_folios; } if (bytes < PAGE_SIZE) memset(kaddr + bytes, 0, PAGE_SIZE - bytes); kunmap_local(kaddr); } for (;;) { struct btrfs_ordered_extent *ordered; ret = btrfs_wait_ordered_range(inode, start, num_bytes); if (ret) goto out_folios; ret = invalidate_inode_pages2_range(inode->vfs_inode.i_mapping, start >> PAGE_SHIFT, end >> PAGE_SHIFT); if (ret) goto out_folios; lock_extent(io_tree, start, end, &cached_state); ordered = btrfs_lookup_ordered_range(inode, start, num_bytes); if (!ordered && !filemap_range_has_page(inode->vfs_inode.i_mapping, start, end)) break; if (ordered) btrfs_put_ordered_extent(ordered); unlock_extent(io_tree, start, end, &cached_state); cond_resched(); } /* * We don't use the higher-level delalloc space functions because our * num_bytes and disk_num_bytes are different. */ ret = btrfs_alloc_data_chunk_ondemand(inode, disk_num_bytes); if (ret) goto out_unlock; ret = btrfs_qgroup_reserve_data(inode, &data_reserved, start, num_bytes); if (ret) goto out_free_data_space; ret = btrfs_delalloc_reserve_metadata(inode, num_bytes, disk_num_bytes, false); if (ret) goto out_qgroup_free_data; /* Try an inline extent first. */ if (encoded->unencoded_len == encoded->len && encoded->unencoded_offset == 0 && can_cow_file_range_inline(inode, start, encoded->len, orig_count)) { ret = __cow_file_range_inline(inode, start, encoded->len, orig_count, compression, folios[0], true); if (ret <= 0) { if (ret == 0) ret = orig_count; goto out_delalloc_release; } } ret = btrfs_reserve_extent(root, disk_num_bytes, disk_num_bytes, disk_num_bytes, 0, 0, &ins, 1, 1); if (ret) goto out_delalloc_release; extent_reserved = true; file_extent.disk_bytenr = ins.objectid; file_extent.disk_num_bytes = ins.offset; file_extent.num_bytes = num_bytes; file_extent.ram_bytes = ram_bytes; file_extent.offset = encoded->unencoded_offset; file_extent.compression = compression; em = btrfs_create_io_em(inode, start, &file_extent, BTRFS_ORDERED_COMPRESSED); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out_free_reserved; } free_extent_map(em); ordered = btrfs_alloc_ordered_extent(inode, start, &file_extent, (1 << BTRFS_ORDERED_ENCODED) | (1 << BTRFS_ORDERED_COMPRESSED)); if (IS_ERR(ordered)) { btrfs_drop_extent_map_range(inode, start, end, false); ret = PTR_ERR(ordered); goto out_free_reserved; } btrfs_dec_block_group_reservations(fs_info, ins.objectid); if (start + encoded->len > inode->vfs_inode.i_size) i_size_write(&inode->vfs_inode, start + encoded->len); unlock_extent(io_tree, start, end, &cached_state); btrfs_delalloc_release_extents(inode, num_bytes); btrfs_submit_compressed_write(ordered, folios, nr_folios, 0, false); ret = orig_count; goto out; out_free_reserved: btrfs_dec_block_group_reservations(fs_info, ins.objectid); btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); out_delalloc_release: btrfs_delalloc_release_extents(inode, num_bytes); btrfs_delalloc_release_metadata(inode, disk_num_bytes, ret < 0); out_qgroup_free_data: if (ret < 0) btrfs_qgroup_free_data(inode, data_reserved, start, num_bytes, NULL); out_free_data_space: /* * If btrfs_reserve_extent() succeeded, then we already decremented * bytes_may_use. */ if (!extent_reserved) btrfs_free_reserved_data_space_noquota(fs_info, disk_num_bytes); out_unlock: unlock_extent(io_tree, start, end, &cached_state); out_folios: for (i = 0; i < nr_folios; i++) { if (folios[i]) folio_put(folios[i]); } kvfree(folios); out: if (ret >= 0) iocb->ki_pos += encoded->len; return ret; } #ifdef CONFIG_SWAP /* * Add an entry indicating a block group or device which is pinned by a * swapfile. Returns 0 on success, 1 if there is already an entry for it, or a * negative errno on failure. */ static int btrfs_add_swapfile_pin(struct inode *inode, void *ptr, bool is_block_group) { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct btrfs_swapfile_pin *sp, *entry; struct rb_node **p; struct rb_node *parent = NULL; sp = kmalloc(sizeof(*sp), GFP_NOFS); if (!sp) return -ENOMEM; sp->ptr = ptr; sp->inode = inode; sp->is_block_group = is_block_group; sp->bg_extent_count = 1; spin_lock(&fs_info->swapfile_pins_lock); p = &fs_info->swapfile_pins.rb_node; while (*p) { parent = *p; entry = rb_entry(parent, struct btrfs_swapfile_pin, node); if (sp->ptr < entry->ptr || (sp->ptr == entry->ptr && sp->inode < entry->inode)) { p = &(*p)->rb_left; } else if (sp->ptr > entry->ptr || (sp->ptr == entry->ptr && sp->inode > entry->inode)) { p = &(*p)->rb_right; } else { if (is_block_group) entry->bg_extent_count++; spin_unlock(&fs_info->swapfile_pins_lock); kfree(sp); return 1; } } rb_link_node(&sp->node, parent, p); rb_insert_color(&sp->node, &fs_info->swapfile_pins); spin_unlock(&fs_info->swapfile_pins_lock); return 0; } /* Free all of the entries pinned by this swapfile. */ static void btrfs_free_swapfile_pins(struct inode *inode) { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct btrfs_swapfile_pin *sp; struct rb_node *node, *next; spin_lock(&fs_info->swapfile_pins_lock); node = rb_first(&fs_info->swapfile_pins); while (node) { next = rb_next(node); sp = rb_entry(node, struct btrfs_swapfile_pin, node); if (sp->inode == inode) { rb_erase(&sp->node, &fs_info->swapfile_pins); if (sp->is_block_group) { btrfs_dec_block_group_swap_extents(sp->ptr, sp->bg_extent_count); btrfs_put_block_group(sp->ptr); } kfree(sp); } node = next; } spin_unlock(&fs_info->swapfile_pins_lock); } struct btrfs_swap_info { u64 start; u64 block_start; u64 block_len; u64 lowest_ppage; u64 highest_ppage; unsigned long nr_pages; int nr_extents; }; static int btrfs_add_swap_extent(struct swap_info_struct *sis, struct btrfs_swap_info *bsi) { unsigned long nr_pages; unsigned long max_pages; u64 first_ppage, first_ppage_reported, next_ppage; int ret; /* * Our swapfile may have had its size extended after the swap header was * written. In that case activating the swapfile should not go beyond * the max size set in the swap header. */ if (bsi->nr_pages >= sis->max) return 0; max_pages = sis->max - bsi->nr_pages; first_ppage = PAGE_ALIGN(bsi->block_start) >> PAGE_SHIFT; next_ppage = PAGE_ALIGN_DOWN(bsi->block_start + bsi->block_len) >> PAGE_SHIFT; if (first_ppage >= next_ppage) return 0; nr_pages = next_ppage - first_ppage; nr_pages = min(nr_pages, max_pages); first_ppage_reported = first_ppage; if (bsi->start == 0) first_ppage_reported++; if (bsi->lowest_ppage > first_ppage_reported) bsi->lowest_ppage = first_ppage_reported; if (bsi->highest_ppage < (next_ppage - 1)) bsi->highest_ppage = next_ppage - 1; ret = add_swap_extent(sis, bsi->nr_pages, nr_pages, first_ppage); if (ret < 0) return ret; bsi->nr_extents += ret; bsi->nr_pages += nr_pages; return 0; } static void btrfs_swap_deactivate(struct file *file) { struct inode *inode = file_inode(file); btrfs_free_swapfile_pins(inode); atomic_dec(&BTRFS_I(inode)->root->nr_swapfiles); } static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file, sector_t *span) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_fs_info *fs_info = root->fs_info; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_state *cached_state = NULL; struct extent_map *em = NULL; struct btrfs_chunk_map *map = NULL; struct btrfs_device *device = NULL; struct btrfs_swap_info bsi = { .lowest_ppage = (sector_t)-1ULL, }; int ret = 0; u64 isize; u64 start; /* * If the swap file was just created, make sure delalloc is done. If the * file changes again after this, the user is doing something stupid and * we don't really care. */ ret = btrfs_wait_ordered_range(BTRFS_I(inode), 0, (u64)-1); if (ret) return ret; /* * The inode is locked, so these flags won't change after we check them. */ if (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS) { btrfs_warn(fs_info, "swapfile must not be compressed"); return -EINVAL; } if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)) { btrfs_warn(fs_info, "swapfile must not be copy-on-write"); return -EINVAL; } if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { btrfs_warn(fs_info, "swapfile must not be checksummed"); return -EINVAL; } /* * Balance or device remove/replace/resize can move stuff around from * under us. The exclop protection makes sure they aren't running/won't * run concurrently while we are mapping the swap extents, and * fs_info->swapfile_pins prevents them from running while the swap * file is active and moving the extents. Note that this also prevents * a concurrent device add which isn't actually necessary, but it's not * really worth the trouble to allow it. */ if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_SWAP_ACTIVATE)) { btrfs_warn(fs_info, "cannot activate swapfile while exclusive operation is running"); return -EBUSY; } /* * Prevent snapshot creation while we are activating the swap file. * We do not want to race with snapshot creation. If snapshot creation * already started before we bumped nr_swapfiles from 0 to 1 and * completes before the first write into the swap file after it is * activated, than that write would fallback to COW. */ if (!btrfs_drew_try_write_lock(&root->snapshot_lock)) { btrfs_exclop_finish(fs_info); btrfs_warn(fs_info, "cannot activate swapfile because snapshot creation is in progress"); return -EINVAL; } /* * Snapshots can create extents which require COW even if NODATACOW is * set. We use this counter to prevent snapshots. We must increment it * before walking the extents because we don't want a concurrent * snapshot to run after we've already checked the extents. * * It is possible that subvolume is marked for deletion but still not * removed yet. To prevent this race, we check the root status before * activating the swapfile. */ spin_lock(&root->root_item_lock); if (btrfs_root_dead(root)) { spin_unlock(&root->root_item_lock); btrfs_exclop_finish(fs_info); btrfs_warn(fs_info, "cannot activate swapfile because subvolume %llu is being deleted", btrfs_root_id(root)); return -EPERM; } atomic_inc(&root->nr_swapfiles); spin_unlock(&root->root_item_lock); isize = ALIGN_DOWN(inode->i_size, fs_info->sectorsize); lock_extent(io_tree, 0, isize - 1, &cached_state); start = 0; while (start < isize) { u64 logical_block_start, physical_block_start; struct btrfs_block_group *bg; u64 len = isize - start; em = btrfs_get_extent(BTRFS_I(inode), NULL, start, len); if (IS_ERR(em)) { ret = PTR_ERR(em); goto out; } if (em->disk_bytenr == EXTENT_MAP_HOLE) { btrfs_warn(fs_info, "swapfile must not have holes"); ret = -EINVAL; goto out; } if (em->disk_bytenr == EXTENT_MAP_INLINE) { /* * It's unlikely we'll ever actually find ourselves * here, as a file small enough to fit inline won't be * big enough to store more than the swap header, but in * case something changes in the future, let's catch it * here rather than later. */ btrfs_warn(fs_info, "swapfile must not be inline"); ret = -EINVAL; goto out; } if (extent_map_is_compressed(em)) { btrfs_warn(fs_info, "swapfile must not be compressed"); ret = -EINVAL; goto out; } logical_block_start = extent_map_block_start(em) + (start - em->start); len = min(len, em->len - (start - em->start)); free_extent_map(em); em = NULL; ret = can_nocow_extent(inode, start, &len, NULL, false, true); if (ret < 0) { goto out; } else if (ret) { ret = 0; } else { btrfs_warn(fs_info, "swapfile must not be copy-on-write"); ret = -EINVAL; goto out; } map = btrfs_get_chunk_map(fs_info, logical_block_start, len); if (IS_ERR(map)) { ret = PTR_ERR(map); goto out; } if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { btrfs_warn(fs_info, "swapfile must have single data profile"); ret = -EINVAL; goto out; } if (device == NULL) { device = map->stripes[0].dev; ret = btrfs_add_swapfile_pin(inode, device, false); if (ret == 1) ret = 0; else if (ret) goto out; } else if (device != map->stripes[0].dev) { btrfs_warn(fs_info, "swapfile must be on one device"); ret = -EINVAL; goto out; } physical_block_start = (map->stripes[0].physical + (logical_block_start - map->start)); len = min(len, map->chunk_len - (logical_block_start - map->start)); btrfs_free_chunk_map(map); map = NULL; bg = btrfs_lookup_block_group(fs_info, logical_block_start); if (!bg) { btrfs_warn(fs_info, "could not find block group containing swapfile"); ret = -EINVAL; goto out; } if (!btrfs_inc_block_group_swap_extents(bg)) { btrfs_warn(fs_info, "block group for swapfile at %llu is read-only%s", bg->start, atomic_read(&fs_info->scrubs_running) ? " (scrub running)" : ""); btrfs_put_block_group(bg); ret = -EINVAL; goto out; } ret = btrfs_add_swapfile_pin(inode, bg, true); if (ret) { btrfs_put_block_group(bg); if (ret == 1) ret = 0; else goto out; } if (bsi.block_len && bsi.block_start + bsi.block_len == physical_block_start) { bsi.block_len += len; } else { if (bsi.block_len) { ret = btrfs_add_swap_extent(sis, &bsi); if (ret) goto out; } bsi.start = start; bsi.block_start = physical_block_start; bsi.block_len = len; } start += len; } if (bsi.block_len) ret = btrfs_add_swap_extent(sis, &bsi); out: if (!IS_ERR_OR_NULL(em)) free_extent_map(em); if (!IS_ERR_OR_NULL(map)) btrfs_free_chunk_map(map); unlock_extent(io_tree, 0, isize - 1, &cached_state); if (ret) btrfs_swap_deactivate(file); btrfs_drew_write_unlock(&root->snapshot_lock); btrfs_exclop_finish(fs_info); if (ret) return ret; if (device) sis->bdev = device->bdev; *span = bsi.highest_ppage - bsi.lowest_ppage + 1; sis->max = bsi.nr_pages; sis->pages = bsi.nr_pages - 1; sis->highest_bit = bsi.nr_pages - 1; return bsi.nr_extents; } #else static void btrfs_swap_deactivate(struct file *file) { } static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file, sector_t *span) { return -EOPNOTSUPP; } #endif /* * Update the number of bytes used in the VFS' inode. When we replace extents in * a range (clone, dedupe, fallocate's zero range), we must update the number of * bytes used by the inode in an atomic manner, so that concurrent stat(2) calls * always get a correct value. */ void btrfs_update_inode_bytes(struct btrfs_inode *inode, const u64 add_bytes, const u64 del_bytes) { if (add_bytes == del_bytes) return; spin_lock(&inode->lock); if (del_bytes > 0) inode_sub_bytes(&inode->vfs_inode, del_bytes); if (add_bytes > 0) inode_add_bytes(&inode->vfs_inode, add_bytes); spin_unlock(&inode->lock); } /* * Verify that there are no ordered extents for a given file range. * * @inode: The target inode. * @start: Start offset of the file range, should be sector size aligned. * @end: End offset (inclusive) of the file range, its value +1 should be * sector size aligned. * * This should typically be used for cases where we locked an inode's VFS lock in * exclusive mode, we have also locked the inode's i_mmap_lock in exclusive mode, * we have flushed all delalloc in the range, we have waited for all ordered * extents in the range to complete and finally we have locked the file range in * the inode's io_tree. */ void btrfs_assert_inode_range_clean(struct btrfs_inode *inode, u64 start, u64 end) { struct btrfs_root *root = inode->root; struct btrfs_ordered_extent *ordered; if (!IS_ENABLED(CONFIG_BTRFS_ASSERT)) return; ordered = btrfs_lookup_first_ordered_range(inode, start, end + 1 - start); if (ordered) { btrfs_err(root->fs_info, "found unexpected ordered extent in file range [%llu, %llu] for inode %llu root %llu (ordered range [%llu, %llu])", start, end, btrfs_ino(inode), btrfs_root_id(root), ordered->file_offset, ordered->file_offset + ordered->num_bytes - 1); btrfs_put_ordered_extent(ordered); } ASSERT(ordered == NULL); } /* * Find the first inode with a minimum number. * * @root: The root to search for. * @min_ino: The minimum inode number. * * Find the first inode in the @root with a number >= @min_ino and return it. * Returns NULL if no such inode found. */ struct btrfs_inode *btrfs_find_first_inode(struct btrfs_root *root, u64 min_ino) { struct btrfs_inode *inode; unsigned long from = min_ino; xa_lock(&root->inodes); while (true) { inode = xa_find(&root->inodes, &from, ULONG_MAX, XA_PRESENT); if (!inode) break; if (igrab(&inode->vfs_inode)) break; from = btrfs_ino(inode) + 1; cond_resched_lock(&root->inodes.xa_lock); } xa_unlock(&root->inodes); return inode; } static const struct inode_operations btrfs_dir_inode_operations = { .getattr = btrfs_getattr, .lookup = btrfs_lookup, .create = btrfs_create, .unlink = btrfs_unlink, .link = btrfs_link, .mkdir = btrfs_mkdir, .rmdir = btrfs_rmdir, .rename = btrfs_rename2, .symlink = btrfs_symlink, .setattr = btrfs_setattr, .mknod = btrfs_mknod, .listxattr = btrfs_listxattr, .permission = btrfs_permission, .get_inode_acl = btrfs_get_acl, .set_acl = btrfs_set_acl, .update_time = btrfs_update_time, .tmpfile = btrfs_tmpfile, .fileattr_get = btrfs_fileattr_get, .fileattr_set = btrfs_fileattr_set, }; static const struct file_operations btrfs_dir_file_operations = { .llseek = btrfs_dir_llseek, .read = generic_read_dir, .iterate_shared = btrfs_real_readdir, .open = btrfs_opendir, .unlocked_ioctl = btrfs_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = btrfs_compat_ioctl, #endif .release = btrfs_release_file, .fsync = btrfs_sync_file, }; /* * btrfs doesn't support the bmap operation because swapfiles * use bmap to make a mapping of extents in the file. They assume * these extents won't change over the life of the file and they * use the bmap result to do IO directly to the drive. * * the btrfs bmap call would return logical addresses that aren't * suitable for IO and they also will change frequently as COW * operations happen. So, swapfile + btrfs == corruption. * * For now we're avoiding this by dropping bmap. */ static const struct address_space_operations btrfs_aops = { .read_folio = btrfs_read_folio, .writepages = btrfs_writepages, .readahead = btrfs_readahead, .invalidate_folio = btrfs_invalidate_folio, .launder_folio = btrfs_launder_folio, .release_folio = btrfs_release_folio, .migrate_folio = btrfs_migrate_folio, .dirty_folio = filemap_dirty_folio, .error_remove_folio = generic_error_remove_folio, .swap_activate = btrfs_swap_activate, .swap_deactivate = btrfs_swap_deactivate, }; static const struct inode_operations btrfs_file_inode_operations = { .getattr = btrfs_getattr, .setattr = btrfs_setattr, .listxattr = btrfs_listxattr, .permission = btrfs_permission, .fiemap = btrfs_fiemap, .get_inode_acl = btrfs_get_acl, .set_acl = btrfs_set_acl, .update_time = btrfs_update_time, .fileattr_get = btrfs_fileattr_get, .fileattr_set = btrfs_fileattr_set, }; static const struct inode_operations btrfs_special_inode_operations = { .getattr = btrfs_getattr, .setattr = btrfs_setattr, .permission = btrfs_permission, .listxattr = btrfs_listxattr, .get_inode_acl = btrfs_get_acl, .set_acl = btrfs_set_acl, .update_time = btrfs_update_time, }; static const struct inode_operations btrfs_symlink_inode_operations = { .get_link = page_get_link, .getattr = btrfs_getattr, .setattr = btrfs_setattr, .permission = btrfs_permission, .listxattr = btrfs_listxattr, .update_time = btrfs_update_time, }; const struct dentry_operations btrfs_dentry_operations = { .d_delete = btrfs_dentry_delete, };