mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 02:23:16 +00:00
1dc51b8288
Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...
2864 lines
76 KiB
C
2864 lines
76 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/time.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/backing-dev.h>
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#include <linux/mpage.h>
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#include <linux/falloc.h>
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#include <linux/swap.h>
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#include <linux/writeback.h>
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#include <linux/statfs.h>
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#include <linux/compat.h>
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#include <linux/slab.h>
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#include <linux/btrfs.h>
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#include <linux/uio.h>
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#include "ctree.h"
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#include "disk-io.h"
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#include "transaction.h"
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#include "btrfs_inode.h"
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#include "print-tree.h"
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#include "tree-log.h"
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#include "locking.h"
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#include "volumes.h"
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#include "qgroup.h"
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static struct kmem_cache *btrfs_inode_defrag_cachep;
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/*
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* when auto defrag is enabled we
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* queue up these defrag structs to remember which
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* inodes need defragging passes
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*/
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struct inode_defrag {
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struct rb_node rb_node;
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/* objectid */
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u64 ino;
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/*
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* transid where the defrag was added, we search for
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* extents newer than this
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*/
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u64 transid;
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/* root objectid */
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u64 root;
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/* last offset we were able to defrag */
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u64 last_offset;
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/* if we've wrapped around back to zero once already */
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int cycled;
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};
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static int __compare_inode_defrag(struct inode_defrag *defrag1,
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struct inode_defrag *defrag2)
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{
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if (defrag1->root > defrag2->root)
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return 1;
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else if (defrag1->root < defrag2->root)
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return -1;
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else if (defrag1->ino > defrag2->ino)
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return 1;
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else if (defrag1->ino < defrag2->ino)
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return -1;
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else
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return 0;
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}
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/* pop a record for an inode into the defrag tree. The lock
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* must be held already
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*
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* If you're inserting a record for an older transid than an
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* existing record, the transid already in the tree is lowered
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*
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* If an existing record is found the defrag item you
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* pass in is freed
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*/
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static int __btrfs_add_inode_defrag(struct inode *inode,
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struct inode_defrag *defrag)
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{
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struct btrfs_root *root = BTRFS_I(inode)->root;
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struct inode_defrag *entry;
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struct rb_node **p;
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struct rb_node *parent = NULL;
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int ret;
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p = &root->fs_info->defrag_inodes.rb_node;
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while (*p) {
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parent = *p;
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entry = rb_entry(parent, struct inode_defrag, rb_node);
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ret = __compare_inode_defrag(defrag, entry);
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if (ret < 0)
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p = &parent->rb_left;
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else if (ret > 0)
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p = &parent->rb_right;
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else {
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/* if we're reinserting an entry for
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* an old defrag run, make sure to
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* lower the transid of our existing record
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*/
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if (defrag->transid < entry->transid)
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entry->transid = defrag->transid;
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if (defrag->last_offset > entry->last_offset)
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entry->last_offset = defrag->last_offset;
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return -EEXIST;
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}
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}
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set_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
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rb_link_node(&defrag->rb_node, parent, p);
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rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes);
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return 0;
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}
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static inline int __need_auto_defrag(struct btrfs_root *root)
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{
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if (!btrfs_test_opt(root, AUTO_DEFRAG))
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return 0;
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if (btrfs_fs_closing(root->fs_info))
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return 0;
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return 1;
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}
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/*
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* insert a defrag record for this inode if auto defrag is
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* enabled
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*/
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int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
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struct inode *inode)
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{
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struct btrfs_root *root = BTRFS_I(inode)->root;
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struct inode_defrag *defrag;
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u64 transid;
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int ret;
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if (!__need_auto_defrag(root))
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return 0;
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if (test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags))
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return 0;
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if (trans)
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transid = trans->transid;
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else
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transid = BTRFS_I(inode)->root->last_trans;
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defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS);
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if (!defrag)
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return -ENOMEM;
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defrag->ino = btrfs_ino(inode);
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defrag->transid = transid;
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defrag->root = root->root_key.objectid;
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spin_lock(&root->fs_info->defrag_inodes_lock);
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if (!test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags)) {
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/*
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* If we set IN_DEFRAG flag and evict the inode from memory,
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* and then re-read this inode, this new inode doesn't have
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* IN_DEFRAG flag. At the case, we may find the existed defrag.
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*/
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ret = __btrfs_add_inode_defrag(inode, defrag);
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if (ret)
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kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
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} else {
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kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
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}
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spin_unlock(&root->fs_info->defrag_inodes_lock);
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return 0;
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}
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/*
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* Requeue the defrag object. If there is a defrag object that points to
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* the same inode in the tree, we will merge them together (by
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* __btrfs_add_inode_defrag()) and free the one that we want to requeue.
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*/
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static void btrfs_requeue_inode_defrag(struct inode *inode,
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struct inode_defrag *defrag)
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{
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struct btrfs_root *root = BTRFS_I(inode)->root;
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int ret;
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if (!__need_auto_defrag(root))
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goto out;
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/*
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* Here we don't check the IN_DEFRAG flag, because we need merge
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* them together.
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*/
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spin_lock(&root->fs_info->defrag_inodes_lock);
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ret = __btrfs_add_inode_defrag(inode, defrag);
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spin_unlock(&root->fs_info->defrag_inodes_lock);
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if (ret)
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goto out;
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return;
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out:
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kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
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}
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/*
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* pick the defragable inode that we want, if it doesn't exist, we will get
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* the next one.
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*/
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static struct inode_defrag *
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btrfs_pick_defrag_inode(struct btrfs_fs_info *fs_info, u64 root, u64 ino)
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{
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struct inode_defrag *entry = NULL;
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struct inode_defrag tmp;
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struct rb_node *p;
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struct rb_node *parent = NULL;
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int ret;
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tmp.ino = ino;
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tmp.root = root;
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spin_lock(&fs_info->defrag_inodes_lock);
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p = fs_info->defrag_inodes.rb_node;
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while (p) {
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parent = p;
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entry = rb_entry(parent, struct inode_defrag, rb_node);
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ret = __compare_inode_defrag(&tmp, entry);
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if (ret < 0)
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p = parent->rb_left;
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else if (ret > 0)
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p = parent->rb_right;
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else
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goto out;
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}
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if (parent && __compare_inode_defrag(&tmp, entry) > 0) {
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parent = rb_next(parent);
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if (parent)
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entry = rb_entry(parent, struct inode_defrag, rb_node);
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else
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entry = NULL;
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}
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out:
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if (entry)
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rb_erase(parent, &fs_info->defrag_inodes);
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spin_unlock(&fs_info->defrag_inodes_lock);
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return entry;
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}
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void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info)
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{
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struct inode_defrag *defrag;
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struct rb_node *node;
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spin_lock(&fs_info->defrag_inodes_lock);
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node = rb_first(&fs_info->defrag_inodes);
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while (node) {
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rb_erase(node, &fs_info->defrag_inodes);
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defrag = rb_entry(node, struct inode_defrag, rb_node);
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kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
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cond_resched_lock(&fs_info->defrag_inodes_lock);
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node = rb_first(&fs_info->defrag_inodes);
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}
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spin_unlock(&fs_info->defrag_inodes_lock);
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}
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#define BTRFS_DEFRAG_BATCH 1024
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static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
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struct inode_defrag *defrag)
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{
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struct btrfs_root *inode_root;
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struct inode *inode;
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struct btrfs_key key;
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struct btrfs_ioctl_defrag_range_args range;
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int num_defrag;
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int index;
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int ret;
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/* get the inode */
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key.objectid = defrag->root;
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key.type = BTRFS_ROOT_ITEM_KEY;
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key.offset = (u64)-1;
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index = srcu_read_lock(&fs_info->subvol_srcu);
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inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
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if (IS_ERR(inode_root)) {
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ret = PTR_ERR(inode_root);
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goto cleanup;
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}
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key.objectid = defrag->ino;
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key.type = BTRFS_INODE_ITEM_KEY;
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key.offset = 0;
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inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
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if (IS_ERR(inode)) {
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ret = PTR_ERR(inode);
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goto cleanup;
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}
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srcu_read_unlock(&fs_info->subvol_srcu, index);
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/* do a chunk of defrag */
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clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
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memset(&range, 0, sizeof(range));
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range.len = (u64)-1;
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range.start = defrag->last_offset;
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sb_start_write(fs_info->sb);
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num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
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BTRFS_DEFRAG_BATCH);
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sb_end_write(fs_info->sb);
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/*
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* if we filled the whole defrag batch, there
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* must be more work to do. Queue this defrag
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* again
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*/
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if (num_defrag == BTRFS_DEFRAG_BATCH) {
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defrag->last_offset = range.start;
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btrfs_requeue_inode_defrag(inode, defrag);
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} else if (defrag->last_offset && !defrag->cycled) {
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/*
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* we didn't fill our defrag batch, but
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* we didn't start at zero. Make sure we loop
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* around to the start of the file.
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*/
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defrag->last_offset = 0;
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defrag->cycled = 1;
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btrfs_requeue_inode_defrag(inode, defrag);
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} else {
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kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
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}
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iput(inode);
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return 0;
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cleanup:
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srcu_read_unlock(&fs_info->subvol_srcu, index);
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kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
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return ret;
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}
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|
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/*
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* run through the list of inodes in the FS that need
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* defragging
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*/
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int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
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{
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struct inode_defrag *defrag;
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u64 first_ino = 0;
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u64 root_objectid = 0;
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atomic_inc(&fs_info->defrag_running);
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while (1) {
|
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/* Pause the auto defragger. */
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if (test_bit(BTRFS_FS_STATE_REMOUNTING,
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&fs_info->fs_state))
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break;
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if (!__need_auto_defrag(fs_info->tree_root))
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break;
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/* find an inode to defrag */
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defrag = btrfs_pick_defrag_inode(fs_info, root_objectid,
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first_ino);
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if (!defrag) {
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if (root_objectid || first_ino) {
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root_objectid = 0;
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first_ino = 0;
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continue;
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} else {
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break;
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}
|
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}
|
|
|
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first_ino = defrag->ino + 1;
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root_objectid = defrag->root;
|
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|
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__btrfs_run_defrag_inode(fs_info, defrag);
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}
|
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atomic_dec(&fs_info->defrag_running);
|
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|
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/*
|
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* during unmount, we use the transaction_wait queue to
|
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* wait for the defragger to stop
|
|
*/
|
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wake_up(&fs_info->transaction_wait);
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return 0;
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}
|
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|
|
/* simple helper to fault in pages and copy. This should go away
|
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* and be replaced with calls into generic code.
|
|
*/
|
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static noinline int btrfs_copy_from_user(loff_t pos, int num_pages,
|
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size_t write_bytes,
|
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struct page **prepared_pages,
|
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struct iov_iter *i)
|
|
{
|
|
size_t copied = 0;
|
|
size_t total_copied = 0;
|
|
int pg = 0;
|
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int offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
|
|
while (write_bytes > 0) {
|
|
size_t count = min_t(size_t,
|
|
PAGE_CACHE_SIZE - offset, write_bytes);
|
|
struct page *page = prepared_pages[pg];
|
|
/*
|
|
* Copy data from userspace to the current page
|
|
*/
|
|
copied = iov_iter_copy_from_user_atomic(page, i, offset, count);
|
|
|
|
/* Flush processor's dcache for this page */
|
|
flush_dcache_page(page);
|
|
|
|
/*
|
|
* if we get a partial write, we can end up with
|
|
* partially up to date pages. These add
|
|
* a lot of complexity, so make sure they don't
|
|
* happen by forcing this copy to be retried.
|
|
*
|
|
* The rest of the btrfs_file_write code will fall
|
|
* back to page at a time copies after we return 0.
|
|
*/
|
|
if (!PageUptodate(page) && copied < count)
|
|
copied = 0;
|
|
|
|
iov_iter_advance(i, copied);
|
|
write_bytes -= copied;
|
|
total_copied += copied;
|
|
|
|
/* Return to btrfs_file_write_iter to fault page */
|
|
if (unlikely(copied == 0))
|
|
break;
|
|
|
|
if (copied < PAGE_CACHE_SIZE - offset) {
|
|
offset += copied;
|
|
} else {
|
|
pg++;
|
|
offset = 0;
|
|
}
|
|
}
|
|
return total_copied;
|
|
}
|
|
|
|
/*
|
|
* unlocks pages after btrfs_file_write is done with them
|
|
*/
|
|
static void btrfs_drop_pages(struct page **pages, size_t num_pages)
|
|
{
|
|
size_t i;
|
|
for (i = 0; i < num_pages; i++) {
|
|
/* page checked is some magic around finding pages that
|
|
* have been modified without going through btrfs_set_page_dirty
|
|
* clear it here. There should be no need to mark the pages
|
|
* accessed as prepare_pages should have marked them accessed
|
|
* in prepare_pages via find_or_create_page()
|
|
*/
|
|
ClearPageChecked(pages[i]);
|
|
unlock_page(pages[i]);
|
|
page_cache_release(pages[i]);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* after copy_from_user, pages need to be dirtied and we need to make
|
|
* sure holes are created between the current EOF and the start of
|
|
* any next extents (if required).
|
|
*
|
|
* this also makes the decision about creating an inline extent vs
|
|
* doing real data extents, marking pages dirty and delalloc as required.
|
|
*/
|
|
int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode,
|
|
struct page **pages, size_t num_pages,
|
|
loff_t pos, size_t write_bytes,
|
|
struct extent_state **cached)
|
|
{
|
|
int err = 0;
|
|
int i;
|
|
u64 num_bytes;
|
|
u64 start_pos;
|
|
u64 end_of_last_block;
|
|
u64 end_pos = pos + write_bytes;
|
|
loff_t isize = i_size_read(inode);
|
|
|
|
start_pos = pos & ~((u64)root->sectorsize - 1);
|
|
num_bytes = ALIGN(write_bytes + pos - start_pos, root->sectorsize);
|
|
|
|
end_of_last_block = start_pos + num_bytes - 1;
|
|
err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
|
|
cached);
|
|
if (err)
|
|
return err;
|
|
|
|
for (i = 0; i < num_pages; i++) {
|
|
struct page *p = pages[i];
|
|
SetPageUptodate(p);
|
|
ClearPageChecked(p);
|
|
set_page_dirty(p);
|
|
}
|
|
|
|
/*
|
|
* we've only changed i_size in ram, and we haven't updated
|
|
* the disk i_size. There is no need to log the inode
|
|
* at this time.
|
|
*/
|
|
if (end_pos > isize)
|
|
i_size_write(inode, end_pos);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* this drops all the extents in the cache that intersect the range
|
|
* [start, end]. Existing extents are split as required.
|
|
*/
|
|
void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
|
|
int skip_pinned)
|
|
{
|
|
struct extent_map *em;
|
|
struct extent_map *split = NULL;
|
|
struct extent_map *split2 = NULL;
|
|
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
|
|
u64 len = end - start + 1;
|
|
u64 gen;
|
|
int ret;
|
|
int testend = 1;
|
|
unsigned long flags;
|
|
int compressed = 0;
|
|
bool modified;
|
|
|
|
WARN_ON(end < start);
|
|
if (end == (u64)-1) {
|
|
len = (u64)-1;
|
|
testend = 0;
|
|
}
|
|
while (1) {
|
|
int no_splits = 0;
|
|
|
|
modified = false;
|
|
if (!split)
|
|
split = alloc_extent_map();
|
|
if (!split2)
|
|
split2 = alloc_extent_map();
|
|
if (!split || !split2)
|
|
no_splits = 1;
|
|
|
|
write_lock(&em_tree->lock);
|
|
em = lookup_extent_mapping(em_tree, start, len);
|
|
if (!em) {
|
|
write_unlock(&em_tree->lock);
|
|
break;
|
|
}
|
|
flags = em->flags;
|
|
gen = em->generation;
|
|
if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
|
|
if (testend && em->start + em->len >= start + len) {
|
|
free_extent_map(em);
|
|
write_unlock(&em_tree->lock);
|
|
break;
|
|
}
|
|
start = em->start + em->len;
|
|
if (testend)
|
|
len = start + len - (em->start + em->len);
|
|
free_extent_map(em);
|
|
write_unlock(&em_tree->lock);
|
|
continue;
|
|
}
|
|
compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
|
|
clear_bit(EXTENT_FLAG_PINNED, &em->flags);
|
|
clear_bit(EXTENT_FLAG_LOGGING, &flags);
|
|
modified = !list_empty(&em->list);
|
|
if (no_splits)
|
|
goto next;
|
|
|
|
if (em->start < start) {
|
|
split->start = em->start;
|
|
split->len = start - em->start;
|
|
|
|
if (em->block_start < EXTENT_MAP_LAST_BYTE) {
|
|
split->orig_start = em->orig_start;
|
|
split->block_start = em->block_start;
|
|
|
|
if (compressed)
|
|
split->block_len = em->block_len;
|
|
else
|
|
split->block_len = split->len;
|
|
split->orig_block_len = max(split->block_len,
|
|
em->orig_block_len);
|
|
split->ram_bytes = em->ram_bytes;
|
|
} else {
|
|
split->orig_start = split->start;
|
|
split->block_len = 0;
|
|
split->block_start = em->block_start;
|
|
split->orig_block_len = 0;
|
|
split->ram_bytes = split->len;
|
|
}
|
|
|
|
split->generation = gen;
|
|
split->bdev = em->bdev;
|
|
split->flags = flags;
|
|
split->compress_type = em->compress_type;
|
|
replace_extent_mapping(em_tree, em, split, modified);
|
|
free_extent_map(split);
|
|
split = split2;
|
|
split2 = NULL;
|
|
}
|
|
if (testend && em->start + em->len > start + len) {
|
|
u64 diff = start + len - em->start;
|
|
|
|
split->start = start + len;
|
|
split->len = em->start + em->len - (start + len);
|
|
split->bdev = em->bdev;
|
|
split->flags = flags;
|
|
split->compress_type = em->compress_type;
|
|
split->generation = gen;
|
|
|
|
if (em->block_start < EXTENT_MAP_LAST_BYTE) {
|
|
split->orig_block_len = max(em->block_len,
|
|
em->orig_block_len);
|
|
|
|
split->ram_bytes = em->ram_bytes;
|
|
if (compressed) {
|
|
split->block_len = em->block_len;
|
|
split->block_start = em->block_start;
|
|
split->orig_start = em->orig_start;
|
|
} else {
|
|
split->block_len = split->len;
|
|
split->block_start = em->block_start
|
|
+ diff;
|
|
split->orig_start = em->orig_start;
|
|
}
|
|
} else {
|
|
split->ram_bytes = split->len;
|
|
split->orig_start = split->start;
|
|
split->block_len = 0;
|
|
split->block_start = em->block_start;
|
|
split->orig_block_len = 0;
|
|
}
|
|
|
|
if (extent_map_in_tree(em)) {
|
|
replace_extent_mapping(em_tree, em, split,
|
|
modified);
|
|
} else {
|
|
ret = add_extent_mapping(em_tree, split,
|
|
modified);
|
|
ASSERT(ret == 0); /* Logic error */
|
|
}
|
|
free_extent_map(split);
|
|
split = NULL;
|
|
}
|
|
next:
|
|
if (extent_map_in_tree(em))
|
|
remove_extent_mapping(em_tree, em);
|
|
write_unlock(&em_tree->lock);
|
|
|
|
/* once for us */
|
|
free_extent_map(em);
|
|
/* once for the tree*/
|
|
free_extent_map(em);
|
|
}
|
|
if (split)
|
|
free_extent_map(split);
|
|
if (split2)
|
|
free_extent_map(split2);
|
|
}
|
|
|
|
/*
|
|
* this is very complex, but the basic idea is to drop all extents
|
|
* in the range start - end. hint_block is filled in with a block number
|
|
* that would be a good hint to the block allocator for this file.
|
|
*
|
|
* If an extent intersects the range but is not entirely inside the range
|
|
* it is either truncated or split. Anything entirely inside the range
|
|
* is deleted from the tree.
|
|
*/
|
|
int __btrfs_drop_extents(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root, struct inode *inode,
|
|
struct btrfs_path *path, u64 start, u64 end,
|
|
u64 *drop_end, int drop_cache,
|
|
int replace_extent,
|
|
u32 extent_item_size,
|
|
int *key_inserted)
|
|
{
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
struct btrfs_key new_key;
|
|
u64 ino = btrfs_ino(inode);
|
|
u64 search_start = start;
|
|
u64 disk_bytenr = 0;
|
|
u64 num_bytes = 0;
|
|
u64 extent_offset = 0;
|
|
u64 extent_end = 0;
|
|
int del_nr = 0;
|
|
int del_slot = 0;
|
|
int extent_type;
|
|
int recow;
|
|
int ret;
|
|
int modify_tree = -1;
|
|
int update_refs;
|
|
int found = 0;
|
|
int leafs_visited = 0;
|
|
|
|
if (drop_cache)
|
|
btrfs_drop_extent_cache(inode, start, end - 1, 0);
|
|
|
|
if (start >= BTRFS_I(inode)->disk_i_size && !replace_extent)
|
|
modify_tree = 0;
|
|
|
|
update_refs = (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
|
|
root == root->fs_info->tree_root);
|
|
while (1) {
|
|
recow = 0;
|
|
ret = btrfs_lookup_file_extent(trans, root, path, ino,
|
|
search_start, modify_tree);
|
|
if (ret < 0)
|
|
break;
|
|
if (ret > 0 && path->slots[0] > 0 && search_start == start) {
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
|
|
if (key.objectid == ino &&
|
|
key.type == BTRFS_EXTENT_DATA_KEY)
|
|
path->slots[0]--;
|
|
}
|
|
ret = 0;
|
|
leafs_visited++;
|
|
next_slot:
|
|
leaf = path->nodes[0];
|
|
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
|
|
BUG_ON(del_nr > 0);
|
|
ret = btrfs_next_leaf(root, path);
|
|
if (ret < 0)
|
|
break;
|
|
if (ret > 0) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
leafs_visited++;
|
|
leaf = path->nodes[0];
|
|
recow = 1;
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
if (key.objectid > ino ||
|
|
key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
|
|
break;
|
|
|
|
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_REG ||
|
|
extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
|
|
disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
|
|
num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
|
|
extent_offset = btrfs_file_extent_offset(leaf, fi);
|
|
extent_end = key.offset +
|
|
btrfs_file_extent_num_bytes(leaf, fi);
|
|
} else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
extent_end = key.offset +
|
|
btrfs_file_extent_inline_len(leaf,
|
|
path->slots[0], fi);
|
|
} else {
|
|
WARN_ON(1);
|
|
extent_end = search_start;
|
|
}
|
|
|
|
/*
|
|
* Don't skip extent items representing 0 byte lengths. They
|
|
* used to be created (bug) if while punching holes we hit
|
|
* -ENOSPC condition. So if we find one here, just ensure we
|
|
* delete it, otherwise we would insert a new file extent item
|
|
* with the same key (offset) as that 0 bytes length file
|
|
* extent item in the call to setup_items_for_insert() later
|
|
* in this function.
|
|
*/
|
|
if (extent_end == key.offset && extent_end >= search_start)
|
|
goto delete_extent_item;
|
|
|
|
if (extent_end <= search_start) {
|
|
path->slots[0]++;
|
|
goto next_slot;
|
|
}
|
|
|
|
found = 1;
|
|
search_start = max(key.offset, start);
|
|
if (recow || !modify_tree) {
|
|
modify_tree = -1;
|
|
btrfs_release_path(path);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* | - range to drop - |
|
|
* | -------- extent -------- |
|
|
*/
|
|
if (start > key.offset && end < extent_end) {
|
|
BUG_ON(del_nr > 0);
|
|
if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
ret = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
|
|
memcpy(&new_key, &key, sizeof(new_key));
|
|
new_key.offset = start;
|
|
ret = btrfs_duplicate_item(trans, root, path,
|
|
&new_key);
|
|
if (ret == -EAGAIN) {
|
|
btrfs_release_path(path);
|
|
continue;
|
|
}
|
|
if (ret < 0)
|
|
break;
|
|
|
|
leaf = path->nodes[0];
|
|
fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
start - key.offset);
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
|
|
extent_offset += start - key.offset;
|
|
btrfs_set_file_extent_offset(leaf, fi, extent_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - start);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
if (update_refs && disk_bytenr > 0) {
|
|
ret = btrfs_inc_extent_ref(trans, root,
|
|
disk_bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
new_key.objectid,
|
|
start - extent_offset, 1);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
}
|
|
key.offset = start;
|
|
}
|
|
/*
|
|
* | ---- range to drop ----- |
|
|
* | -------- extent -------- |
|
|
*/
|
|
if (start <= key.offset && end < extent_end) {
|
|
if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
ret = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
|
|
memcpy(&new_key, &key, sizeof(new_key));
|
|
new_key.offset = end;
|
|
btrfs_set_item_key_safe(root->fs_info, path, &new_key);
|
|
|
|
extent_offset += end - key.offset;
|
|
btrfs_set_file_extent_offset(leaf, fi, extent_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - end);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
if (update_refs && disk_bytenr > 0)
|
|
inode_sub_bytes(inode, end - key.offset);
|
|
break;
|
|
}
|
|
|
|
search_start = extent_end;
|
|
/*
|
|
* | ---- range to drop ----- |
|
|
* | -------- extent -------- |
|
|
*/
|
|
if (start > key.offset && end >= extent_end) {
|
|
BUG_ON(del_nr > 0);
|
|
if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
ret = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
start - key.offset);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
if (update_refs && disk_bytenr > 0)
|
|
inode_sub_bytes(inode, extent_end - start);
|
|
if (end == extent_end)
|
|
break;
|
|
|
|
path->slots[0]++;
|
|
goto next_slot;
|
|
}
|
|
|
|
/*
|
|
* | ---- range to drop ----- |
|
|
* | ------ extent ------ |
|
|
*/
|
|
if (start <= key.offset && end >= extent_end) {
|
|
delete_extent_item:
|
|
if (del_nr == 0) {
|
|
del_slot = path->slots[0];
|
|
del_nr = 1;
|
|
} else {
|
|
BUG_ON(del_slot + del_nr != path->slots[0]);
|
|
del_nr++;
|
|
}
|
|
|
|
if (update_refs &&
|
|
extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
inode_sub_bytes(inode,
|
|
extent_end - key.offset);
|
|
extent_end = ALIGN(extent_end,
|
|
root->sectorsize);
|
|
} else if (update_refs && disk_bytenr > 0) {
|
|
ret = btrfs_free_extent(trans, root,
|
|
disk_bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
key.objectid, key.offset -
|
|
extent_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
inode_sub_bytes(inode,
|
|
extent_end - key.offset);
|
|
}
|
|
|
|
if (end == extent_end)
|
|
break;
|
|
|
|
if (path->slots[0] + 1 < btrfs_header_nritems(leaf)) {
|
|
path->slots[0]++;
|
|
goto next_slot;
|
|
}
|
|
|
|
ret = btrfs_del_items(trans, root, path, del_slot,
|
|
del_nr);
|
|
if (ret) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
break;
|
|
}
|
|
|
|
del_nr = 0;
|
|
del_slot = 0;
|
|
|
|
btrfs_release_path(path);
|
|
continue;
|
|
}
|
|
|
|
BUG_ON(1);
|
|
}
|
|
|
|
if (!ret && del_nr > 0) {
|
|
/*
|
|
* Set path->slots[0] to first slot, so that after the delete
|
|
* if items are move off from our leaf to its immediate left or
|
|
* right neighbor leafs, we end up with a correct and adjusted
|
|
* path->slots[0] for our insertion (if replace_extent != 0).
|
|
*/
|
|
path->slots[0] = del_slot;
|
|
ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
|
|
if (ret)
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
}
|
|
|
|
leaf = path->nodes[0];
|
|
/*
|
|
* If btrfs_del_items() was called, it might have deleted a leaf, in
|
|
* which case it unlocked our path, so check path->locks[0] matches a
|
|
* write lock.
|
|
*/
|
|
if (!ret && replace_extent && leafs_visited == 1 &&
|
|
(path->locks[0] == BTRFS_WRITE_LOCK_BLOCKING ||
|
|
path->locks[0] == BTRFS_WRITE_LOCK) &&
|
|
btrfs_leaf_free_space(root, leaf) >=
|
|
sizeof(struct btrfs_item) + extent_item_size) {
|
|
|
|
key.objectid = ino;
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
key.offset = start;
|
|
if (!del_nr && path->slots[0] < btrfs_header_nritems(leaf)) {
|
|
struct btrfs_key slot_key;
|
|
|
|
btrfs_item_key_to_cpu(leaf, &slot_key, path->slots[0]);
|
|
if (btrfs_comp_cpu_keys(&key, &slot_key) > 0)
|
|
path->slots[0]++;
|
|
}
|
|
setup_items_for_insert(root, path, &key,
|
|
&extent_item_size,
|
|
extent_item_size,
|
|
sizeof(struct btrfs_item) +
|
|
extent_item_size, 1);
|
|
*key_inserted = 1;
|
|
}
|
|
|
|
if (!replace_extent || !(*key_inserted))
|
|
btrfs_release_path(path);
|
|
if (drop_end)
|
|
*drop_end = found ? min(end, extent_end) : end;
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_drop_extents(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root, struct inode *inode, u64 start,
|
|
u64 end, int drop_cache)
|
|
{
|
|
struct btrfs_path *path;
|
|
int ret;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
ret = __btrfs_drop_extents(trans, root, inode, path, start, end, NULL,
|
|
drop_cache, 0, 0, NULL);
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
static int extent_mergeable(struct extent_buffer *leaf, int slot,
|
|
u64 objectid, u64 bytenr, u64 orig_offset,
|
|
u64 *start, u64 *end)
|
|
{
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
u64 extent_end;
|
|
|
|
if (slot < 0 || slot >= btrfs_header_nritems(leaf))
|
|
return 0;
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, slot);
|
|
if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
|
|
return 0;
|
|
|
|
fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
|
|
if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG ||
|
|
btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr ||
|
|
btrfs_file_extent_offset(leaf, fi) != key.offset - orig_offset ||
|
|
btrfs_file_extent_compression(leaf, fi) ||
|
|
btrfs_file_extent_encryption(leaf, fi) ||
|
|
btrfs_file_extent_other_encoding(leaf, fi))
|
|
return 0;
|
|
|
|
extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
|
|
if ((*start && *start != key.offset) || (*end && *end != extent_end))
|
|
return 0;
|
|
|
|
*start = key.offset;
|
|
*end = extent_end;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Mark extent in the range start - end as written.
|
|
*
|
|
* This changes extent type from 'pre-allocated' to 'regular'. If only
|
|
* part of extent is marked as written, the extent will be split into
|
|
* two or three.
|
|
*/
|
|
int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
|
|
struct inode *inode, u64 start, u64 end)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_path *path;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
struct btrfs_key new_key;
|
|
u64 bytenr;
|
|
u64 num_bytes;
|
|
u64 extent_end;
|
|
u64 orig_offset;
|
|
u64 other_start;
|
|
u64 other_end;
|
|
u64 split;
|
|
int del_nr = 0;
|
|
int del_slot = 0;
|
|
int recow;
|
|
int ret;
|
|
u64 ino = btrfs_ino(inode);
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
again:
|
|
recow = 0;
|
|
split = start;
|
|
key.objectid = ino;
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
key.offset = split;
|
|
|
|
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret > 0 && path->slots[0] > 0)
|
|
path->slots[0]--;
|
|
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
BUG_ON(btrfs_file_extent_type(leaf, fi) !=
|
|
BTRFS_FILE_EXTENT_PREALLOC);
|
|
extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
|
|
BUG_ON(key.offset > start || extent_end < end);
|
|
|
|
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
|
|
num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
|
|
orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi);
|
|
memcpy(&new_key, &key, sizeof(new_key));
|
|
|
|
if (start == key.offset && end < extent_end) {
|
|
other_start = 0;
|
|
other_end = start;
|
|
if (extent_mergeable(leaf, path->slots[0] - 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
new_key.offset = end;
|
|
btrfs_set_item_key_safe(root->fs_info, path, &new_key);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_generation(leaf, fi,
|
|
trans->transid);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - end);
|
|
btrfs_set_file_extent_offset(leaf, fi,
|
|
end - orig_offset);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_generation(leaf, fi,
|
|
trans->transid);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
end - other_start);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (start > key.offset && end == extent_end) {
|
|
other_start = end;
|
|
other_end = 0;
|
|
if (extent_mergeable(leaf, path->slots[0] + 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
start - key.offset);
|
|
btrfs_set_file_extent_generation(leaf, fi,
|
|
trans->transid);
|
|
path->slots[0]++;
|
|
new_key.offset = start;
|
|
btrfs_set_item_key_safe(root->fs_info, path, &new_key);
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_generation(leaf, fi,
|
|
trans->transid);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
other_end - start);
|
|
btrfs_set_file_extent_offset(leaf, fi,
|
|
start - orig_offset);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
while (start > key.offset || end < extent_end) {
|
|
if (key.offset == start)
|
|
split = end;
|
|
|
|
new_key.offset = split;
|
|
ret = btrfs_duplicate_item(trans, root, path, &new_key);
|
|
if (ret == -EAGAIN) {
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
if (ret < 0) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
goto out;
|
|
}
|
|
|
|
leaf = path->nodes[0];
|
|
fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
split - key.offset);
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
|
|
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
|
|
btrfs_set_file_extent_offset(leaf, fi, split - orig_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - split);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
ino, orig_offset, 1);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
|
|
if (split == start) {
|
|
key.offset = start;
|
|
} else {
|
|
BUG_ON(start != key.offset);
|
|
path->slots[0]--;
|
|
extent_end = end;
|
|
}
|
|
recow = 1;
|
|
}
|
|
|
|
other_start = end;
|
|
other_end = 0;
|
|
if (extent_mergeable(leaf, path->slots[0] + 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
if (recow) {
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
extent_end = other_end;
|
|
del_slot = path->slots[0] + 1;
|
|
del_nr++;
|
|
ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
|
|
0, root->root_key.objectid,
|
|
ino, orig_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
}
|
|
other_start = 0;
|
|
other_end = start;
|
|
if (extent_mergeable(leaf, path->slots[0] - 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
if (recow) {
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
key.offset = other_start;
|
|
del_slot = path->slots[0];
|
|
del_nr++;
|
|
ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
|
|
0, root->root_key.objectid,
|
|
ino, orig_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
}
|
|
if (del_nr == 0) {
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_type(leaf, fi,
|
|
BTRFS_FILE_EXTENT_REG);
|
|
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
} else {
|
|
fi = btrfs_item_ptr(leaf, del_slot - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_type(leaf, fi,
|
|
BTRFS_FILE_EXTENT_REG);
|
|
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - key.offset);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
|
|
if (ret < 0) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
btrfs_free_path(path);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* on error we return an unlocked page and the error value
|
|
* on success we return a locked page and 0
|
|
*/
|
|
static int prepare_uptodate_page(struct page *page, u64 pos,
|
|
bool force_uptodate)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (((pos & (PAGE_CACHE_SIZE - 1)) || force_uptodate) &&
|
|
!PageUptodate(page)) {
|
|
ret = btrfs_readpage(NULL, page);
|
|
if (ret)
|
|
return ret;
|
|
lock_page(page);
|
|
if (!PageUptodate(page)) {
|
|
unlock_page(page);
|
|
return -EIO;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* this just gets pages into the page cache and locks them down.
|
|
*/
|
|
static noinline int prepare_pages(struct inode *inode, struct page **pages,
|
|
size_t num_pages, loff_t pos,
|
|
size_t write_bytes, bool force_uptodate)
|
|
{
|
|
int i;
|
|
unsigned long index = pos >> PAGE_CACHE_SHIFT;
|
|
gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
|
|
int err = 0;
|
|
int faili;
|
|
|
|
for (i = 0; i < num_pages; i++) {
|
|
pages[i] = find_or_create_page(inode->i_mapping, index + i,
|
|
mask | __GFP_WRITE);
|
|
if (!pages[i]) {
|
|
faili = i - 1;
|
|
err = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
if (i == 0)
|
|
err = prepare_uptodate_page(pages[i], pos,
|
|
force_uptodate);
|
|
if (i == num_pages - 1)
|
|
err = prepare_uptodate_page(pages[i],
|
|
pos + write_bytes, false);
|
|
if (err) {
|
|
page_cache_release(pages[i]);
|
|
faili = i - 1;
|
|
goto fail;
|
|
}
|
|
wait_on_page_writeback(pages[i]);
|
|
}
|
|
|
|
return 0;
|
|
fail:
|
|
while (faili >= 0) {
|
|
unlock_page(pages[faili]);
|
|
page_cache_release(pages[faili]);
|
|
faili--;
|
|
}
|
|
return err;
|
|
|
|
}
|
|
|
|
/*
|
|
* This function locks the extent and properly waits for data=ordered extents
|
|
* to finish before allowing the pages to be modified if need.
|
|
*
|
|
* The return value:
|
|
* 1 - the extent is locked
|
|
* 0 - the extent is not locked, and everything is OK
|
|
* -EAGAIN - need re-prepare the pages
|
|
* the other < 0 number - Something wrong happens
|
|
*/
|
|
static noinline int
|
|
lock_and_cleanup_extent_if_need(struct inode *inode, struct page **pages,
|
|
size_t num_pages, loff_t pos,
|
|
u64 *lockstart, u64 *lockend,
|
|
struct extent_state **cached_state)
|
|
{
|
|
u64 start_pos;
|
|
u64 last_pos;
|
|
int i;
|
|
int ret = 0;
|
|
|
|
start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1);
|
|
last_pos = start_pos + ((u64)num_pages << PAGE_CACHE_SHIFT) - 1;
|
|
|
|
if (start_pos < inode->i_size) {
|
|
struct btrfs_ordered_extent *ordered;
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos, 0, cached_state);
|
|
ordered = btrfs_lookup_ordered_range(inode, start_pos,
|
|
last_pos - start_pos + 1);
|
|
if (ordered &&
|
|
ordered->file_offset + ordered->len > start_pos &&
|
|
ordered->file_offset <= last_pos) {
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos,
|
|
cached_state, GFP_NOFS);
|
|
for (i = 0; i < num_pages; i++) {
|
|
unlock_page(pages[i]);
|
|
page_cache_release(pages[i]);
|
|
}
|
|
btrfs_start_ordered_extent(inode, ordered, 1);
|
|
btrfs_put_ordered_extent(ordered);
|
|
return -EAGAIN;
|
|
}
|
|
if (ordered)
|
|
btrfs_put_ordered_extent(ordered);
|
|
|
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, start_pos,
|
|
last_pos, EXTENT_DIRTY | EXTENT_DELALLOC |
|
|
EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
|
|
0, 0, cached_state, GFP_NOFS);
|
|
*lockstart = start_pos;
|
|
*lockend = last_pos;
|
|
ret = 1;
|
|
}
|
|
|
|
for (i = 0; i < num_pages; i++) {
|
|
if (clear_page_dirty_for_io(pages[i]))
|
|
account_page_redirty(pages[i]);
|
|
set_page_extent_mapped(pages[i]);
|
|
WARN_ON(!PageLocked(pages[i]));
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static noinline int check_can_nocow(struct inode *inode, loff_t pos,
|
|
size_t *write_bytes)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct btrfs_ordered_extent *ordered;
|
|
u64 lockstart, lockend;
|
|
u64 num_bytes;
|
|
int ret;
|
|
|
|
ret = btrfs_start_write_no_snapshoting(root);
|
|
if (!ret)
|
|
return -ENOSPC;
|
|
|
|
lockstart = round_down(pos, root->sectorsize);
|
|
lockend = round_up(pos + *write_bytes, root->sectorsize) - 1;
|
|
|
|
while (1) {
|
|
lock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
|
|
ordered = btrfs_lookup_ordered_range(inode, lockstart,
|
|
lockend - lockstart + 1);
|
|
if (!ordered) {
|
|
break;
|
|
}
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
|
|
btrfs_start_ordered_extent(inode, ordered, 1);
|
|
btrfs_put_ordered_extent(ordered);
|
|
}
|
|
|
|
num_bytes = lockend - lockstart + 1;
|
|
ret = can_nocow_extent(inode, lockstart, &num_bytes, NULL, NULL, NULL);
|
|
if (ret <= 0) {
|
|
ret = 0;
|
|
btrfs_end_write_no_snapshoting(root);
|
|
} else {
|
|
*write_bytes = min_t(size_t, *write_bytes ,
|
|
num_bytes - pos + lockstart);
|
|
}
|
|
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static noinline ssize_t __btrfs_buffered_write(struct file *file,
|
|
struct iov_iter *i,
|
|
loff_t pos)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct page **pages = NULL;
|
|
struct extent_state *cached_state = NULL;
|
|
u64 release_bytes = 0;
|
|
u64 lockstart;
|
|
u64 lockend;
|
|
unsigned long first_index;
|
|
size_t num_written = 0;
|
|
int nrptrs;
|
|
int ret = 0;
|
|
bool only_release_metadata = false;
|
|
bool force_page_uptodate = false;
|
|
bool need_unlock;
|
|
|
|
nrptrs = min(DIV_ROUND_UP(iov_iter_count(i), PAGE_CACHE_SIZE),
|
|
PAGE_CACHE_SIZE / (sizeof(struct page *)));
|
|
nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied);
|
|
nrptrs = max(nrptrs, 8);
|
|
pages = kmalloc_array(nrptrs, sizeof(struct page *), GFP_KERNEL);
|
|
if (!pages)
|
|
return -ENOMEM;
|
|
|
|
first_index = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
while (iov_iter_count(i) > 0) {
|
|
size_t offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
size_t write_bytes = min(iov_iter_count(i),
|
|
nrptrs * (size_t)PAGE_CACHE_SIZE -
|
|
offset);
|
|
size_t num_pages = DIV_ROUND_UP(write_bytes + offset,
|
|
PAGE_CACHE_SIZE);
|
|
size_t reserve_bytes;
|
|
size_t dirty_pages;
|
|
size_t copied;
|
|
|
|
WARN_ON(num_pages > nrptrs);
|
|
|
|
/*
|
|
* Fault pages before locking them in prepare_pages
|
|
* to avoid recursive lock
|
|
*/
|
|
if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
reserve_bytes = num_pages << PAGE_CACHE_SHIFT;
|
|
ret = btrfs_check_data_free_space(inode, reserve_bytes, write_bytes);
|
|
if (ret == -ENOSPC &&
|
|
(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
|
|
BTRFS_INODE_PREALLOC))) {
|
|
ret = check_can_nocow(inode, pos, &write_bytes);
|
|
if (ret > 0) {
|
|
only_release_metadata = true;
|
|
/*
|
|
* our prealloc extent may be smaller than
|
|
* write_bytes, so scale down.
|
|
*/
|
|
num_pages = DIV_ROUND_UP(write_bytes + offset,
|
|
PAGE_CACHE_SIZE);
|
|
reserve_bytes = num_pages << PAGE_CACHE_SHIFT;
|
|
ret = 0;
|
|
} else {
|
|
ret = -ENOSPC;
|
|
}
|
|
}
|
|
|
|
if (ret)
|
|
break;
|
|
|
|
ret = btrfs_delalloc_reserve_metadata(inode, reserve_bytes);
|
|
if (ret) {
|
|
if (!only_release_metadata)
|
|
btrfs_free_reserved_data_space(inode,
|
|
reserve_bytes);
|
|
else
|
|
btrfs_end_write_no_snapshoting(root);
|
|
break;
|
|
}
|
|
|
|
release_bytes = reserve_bytes;
|
|
need_unlock = false;
|
|
again:
|
|
/*
|
|
* This is going to setup the pages array with the number of
|
|
* pages we want, so we don't really need to worry about the
|
|
* contents of pages from loop to loop
|
|
*/
|
|
ret = prepare_pages(inode, pages, num_pages,
|
|
pos, write_bytes,
|
|
force_page_uptodate);
|
|
if (ret)
|
|
break;
|
|
|
|
ret = lock_and_cleanup_extent_if_need(inode, pages, num_pages,
|
|
pos, &lockstart, &lockend,
|
|
&cached_state);
|
|
if (ret < 0) {
|
|
if (ret == -EAGAIN)
|
|
goto again;
|
|
break;
|
|
} else if (ret > 0) {
|
|
need_unlock = true;
|
|
ret = 0;
|
|
}
|
|
|
|
copied = btrfs_copy_from_user(pos, num_pages,
|
|
write_bytes, pages, i);
|
|
|
|
/*
|
|
* if we have trouble faulting in the pages, fall
|
|
* back to one page at a time
|
|
*/
|
|
if (copied < write_bytes)
|
|
nrptrs = 1;
|
|
|
|
if (copied == 0) {
|
|
force_page_uptodate = true;
|
|
dirty_pages = 0;
|
|
} else {
|
|
force_page_uptodate = false;
|
|
dirty_pages = DIV_ROUND_UP(copied + offset,
|
|
PAGE_CACHE_SIZE);
|
|
}
|
|
|
|
/*
|
|
* If we had a short copy we need to release the excess delaloc
|
|
* bytes we reserved. We need to increment outstanding_extents
|
|
* because btrfs_delalloc_release_space will decrement it, but
|
|
* we still have an outstanding extent for the chunk we actually
|
|
* managed to copy.
|
|
*/
|
|
if (num_pages > dirty_pages) {
|
|
release_bytes = (num_pages - dirty_pages) <<
|
|
PAGE_CACHE_SHIFT;
|
|
if (copied > 0) {
|
|
spin_lock(&BTRFS_I(inode)->lock);
|
|
BTRFS_I(inode)->outstanding_extents++;
|
|
spin_unlock(&BTRFS_I(inode)->lock);
|
|
}
|
|
if (only_release_metadata)
|
|
btrfs_delalloc_release_metadata(inode,
|
|
release_bytes);
|
|
else
|
|
btrfs_delalloc_release_space(inode,
|
|
release_bytes);
|
|
}
|
|
|
|
release_bytes = dirty_pages << PAGE_CACHE_SHIFT;
|
|
|
|
if (copied > 0)
|
|
ret = btrfs_dirty_pages(root, inode, pages,
|
|
dirty_pages, pos, copied,
|
|
NULL);
|
|
if (need_unlock)
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
|
|
lockstart, lockend, &cached_state,
|
|
GFP_NOFS);
|
|
if (ret) {
|
|
btrfs_drop_pages(pages, num_pages);
|
|
break;
|
|
}
|
|
|
|
release_bytes = 0;
|
|
if (only_release_metadata)
|
|
btrfs_end_write_no_snapshoting(root);
|
|
|
|
if (only_release_metadata && copied > 0) {
|
|
lockstart = round_down(pos, root->sectorsize);
|
|
lockend = lockstart +
|
|
(dirty_pages << PAGE_CACHE_SHIFT) - 1;
|
|
|
|
set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
|
|
lockend, EXTENT_NORESERVE, NULL,
|
|
NULL, GFP_NOFS);
|
|
only_release_metadata = false;
|
|
}
|
|
|
|
btrfs_drop_pages(pages, num_pages);
|
|
|
|
cond_resched();
|
|
|
|
balance_dirty_pages_ratelimited(inode->i_mapping);
|
|
if (dirty_pages < (root->nodesize >> PAGE_CACHE_SHIFT) + 1)
|
|
btrfs_btree_balance_dirty(root);
|
|
|
|
pos += copied;
|
|
num_written += copied;
|
|
}
|
|
|
|
kfree(pages);
|
|
|
|
if (release_bytes) {
|
|
if (only_release_metadata) {
|
|
btrfs_end_write_no_snapshoting(root);
|
|
btrfs_delalloc_release_metadata(inode, release_bytes);
|
|
} else {
|
|
btrfs_delalloc_release_space(inode, release_bytes);
|
|
}
|
|
}
|
|
|
|
return num_written ? num_written : ret;
|
|
}
|
|
|
|
static ssize_t __btrfs_direct_write(struct kiocb *iocb,
|
|
struct iov_iter *from,
|
|
loff_t pos)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file_inode(file);
|
|
ssize_t written;
|
|
ssize_t written_buffered;
|
|
loff_t endbyte;
|
|
int err;
|
|
|
|
written = generic_file_direct_write(iocb, from, pos);
|
|
|
|
if (written < 0 || !iov_iter_count(from))
|
|
return written;
|
|
|
|
pos += written;
|
|
written_buffered = __btrfs_buffered_write(file, from, pos);
|
|
if (written_buffered < 0) {
|
|
err = written_buffered;
|
|
goto out;
|
|
}
|
|
/*
|
|
* Ensure all data is persisted. We want the next direct IO read to be
|
|
* able to read what was just written.
|
|
*/
|
|
endbyte = pos + written_buffered - 1;
|
|
err = btrfs_fdatawrite_range(inode, pos, endbyte);
|
|
if (err)
|
|
goto out;
|
|
err = filemap_fdatawait_range(inode->i_mapping, pos, endbyte);
|
|
if (err)
|
|
goto out;
|
|
written += written_buffered;
|
|
iocb->ki_pos = pos + written_buffered;
|
|
invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT,
|
|
endbyte >> PAGE_CACHE_SHIFT);
|
|
out:
|
|
return written ? written : err;
|
|
}
|
|
|
|
static void update_time_for_write(struct inode *inode)
|
|
{
|
|
struct timespec now;
|
|
|
|
if (IS_NOCMTIME(inode))
|
|
return;
|
|
|
|
now = current_fs_time(inode->i_sb);
|
|
if (!timespec_equal(&inode->i_mtime, &now))
|
|
inode->i_mtime = now;
|
|
|
|
if (!timespec_equal(&inode->i_ctime, &now))
|
|
inode->i_ctime = now;
|
|
|
|
if (IS_I_VERSION(inode))
|
|
inode_inc_iversion(inode);
|
|
}
|
|
|
|
static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
|
|
struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file_inode(file);
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
u64 start_pos;
|
|
u64 end_pos;
|
|
ssize_t num_written = 0;
|
|
bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);
|
|
ssize_t err;
|
|
loff_t pos;
|
|
size_t count;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
err = generic_write_checks(iocb, from);
|
|
if (err <= 0) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return err;
|
|
}
|
|
|
|
current->backing_dev_info = inode_to_bdi(inode);
|
|
err = file_remove_privs(file);
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* If BTRFS flips readonly due to some impossible error
|
|
* (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
|
|
* although we have opened a file as writable, we have
|
|
* to stop this write operation to ensure FS consistency.
|
|
*/
|
|
if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
err = -EROFS;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* We reserve space for updating the inode when we reserve space for the
|
|
* extent we are going to write, so we will enospc out there. We don't
|
|
* need to start yet another transaction to update the inode as we will
|
|
* update the inode when we finish writing whatever data we write.
|
|
*/
|
|
update_time_for_write(inode);
|
|
|
|
pos = iocb->ki_pos;
|
|
count = iov_iter_count(from);
|
|
start_pos = round_down(pos, root->sectorsize);
|
|
if (start_pos > i_size_read(inode)) {
|
|
/* Expand hole size to cover write data, preventing empty gap */
|
|
end_pos = round_up(pos + count, root->sectorsize);
|
|
err = btrfs_cont_expand(inode, i_size_read(inode), end_pos);
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (sync)
|
|
atomic_inc(&BTRFS_I(inode)->sync_writers);
|
|
|
|
if (iocb->ki_flags & IOCB_DIRECT) {
|
|
num_written = __btrfs_direct_write(iocb, from, pos);
|
|
} else {
|
|
num_written = __btrfs_buffered_write(file, from, pos);
|
|
if (num_written > 0)
|
|
iocb->ki_pos = pos + num_written;
|
|
}
|
|
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
/*
|
|
* We also have to set last_sub_trans to the current log transid,
|
|
* otherwise subsequent syncs to a file that's been synced in this
|
|
* transaction will appear to have already occured.
|
|
*/
|
|
spin_lock(&BTRFS_I(inode)->lock);
|
|
BTRFS_I(inode)->last_sub_trans = root->log_transid;
|
|
spin_unlock(&BTRFS_I(inode)->lock);
|
|
if (num_written > 0) {
|
|
err = generic_write_sync(file, pos, num_written);
|
|
if (err < 0)
|
|
num_written = err;
|
|
}
|
|
|
|
if (sync)
|
|
atomic_dec(&BTRFS_I(inode)->sync_writers);
|
|
out:
|
|
current->backing_dev_info = NULL;
|
|
return num_written ? num_written : err;
|
|
}
|
|
|
|
int btrfs_release_file(struct inode *inode, struct file *filp)
|
|
{
|
|
if (filp->private_data)
|
|
btrfs_ioctl_trans_end(filp);
|
|
/*
|
|
* ordered_data_close is set by settattr when we are about to truncate
|
|
* a file from a non-zero size to a zero size. This tries to
|
|
* flush down new bytes that may have been written if the
|
|
* application were using truncate to replace a file in place.
|
|
*/
|
|
if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
|
|
&BTRFS_I(inode)->runtime_flags))
|
|
filemap_flush(inode->i_mapping);
|
|
return 0;
|
|
}
|
|
|
|
static int start_ordered_ops(struct inode *inode, loff_t start, loff_t end)
|
|
{
|
|
int ret;
|
|
|
|
atomic_inc(&BTRFS_I(inode)->sync_writers);
|
|
ret = btrfs_fdatawrite_range(inode, start, end);
|
|
atomic_dec(&BTRFS_I(inode)->sync_writers);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* fsync call for both files and directories. This logs the inode into
|
|
* the tree log instead of forcing full commits whenever possible.
|
|
*
|
|
* It needs to call filemap_fdatawait so that all ordered extent updates are
|
|
* in the metadata btree are up to date for copying to the log.
|
|
*
|
|
* It drops the inode mutex before doing the tree log commit. This is an
|
|
* important optimization for directories because holding the mutex prevents
|
|
* new operations on the dir while we write to disk.
|
|
*/
|
|
int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
|
|
{
|
|
struct dentry *dentry = file->f_path.dentry;
|
|
struct inode *inode = d_inode(dentry);
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_log_ctx ctx;
|
|
int ret = 0;
|
|
bool full_sync = 0;
|
|
const u64 len = end - start + 1;
|
|
|
|
trace_btrfs_sync_file(file, datasync);
|
|
|
|
/*
|
|
* We write the dirty pages in the range and wait until they complete
|
|
* out of the ->i_mutex. If so, we can flush the dirty pages by
|
|
* multi-task, and make the performance up. See
|
|
* btrfs_wait_ordered_range for an explanation of the ASYNC check.
|
|
*/
|
|
ret = start_ordered_ops(inode, start, end);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
atomic_inc(&root->log_batch);
|
|
full_sync = test_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
|
|
&BTRFS_I(inode)->runtime_flags);
|
|
/*
|
|
* We might have have had more pages made dirty after calling
|
|
* start_ordered_ops and before acquiring the inode's i_mutex.
|
|
*/
|
|
if (full_sync) {
|
|
/*
|
|
* For a full sync, we need to make sure any ordered operations
|
|
* start and finish before we start logging the inode, so that
|
|
* all extents are persisted and the respective file extent
|
|
* items are in the fs/subvol btree.
|
|
*/
|
|
ret = btrfs_wait_ordered_range(inode, start, len);
|
|
} else {
|
|
/*
|
|
* Start any new ordered operations before starting to log the
|
|
* inode. We will wait for them to finish in btrfs_sync_log().
|
|
*
|
|
* Right before acquiring the inode's mutex, we might have new
|
|
* writes dirtying pages, which won't immediately start the
|
|
* respective ordered operations - that is done through the
|
|
* fill_delalloc callbacks invoked from the writepage and
|
|
* writepages address space operations. So make sure we start
|
|
* all ordered operations before starting to log our inode. Not
|
|
* doing this means that while logging the inode, writeback
|
|
* could start and invoke writepage/writepages, which would call
|
|
* the fill_delalloc callbacks (cow_file_range,
|
|
* submit_compressed_extents). These callbacks add first an
|
|
* extent map to the modified list of extents and then create
|
|
* the respective ordered operation, which means in
|
|
* tree-log.c:btrfs_log_inode() we might capture all existing
|
|
* ordered operations (with btrfs_get_logged_extents()) before
|
|
* the fill_delalloc callback adds its ordered operation, and by
|
|
* the time we visit the modified list of extent maps (with
|
|
* btrfs_log_changed_extents()), we see and process the extent
|
|
* map they created. We then use the extent map to construct a
|
|
* file extent item for logging without waiting for the
|
|
* respective ordered operation to finish - this file extent
|
|
* item points to a disk location that might not have yet been
|
|
* written to, containing random data - so after a crash a log
|
|
* replay will make our inode have file extent items that point
|
|
* to disk locations containing invalid data, as we returned
|
|
* success to userspace without waiting for the respective
|
|
* ordered operation to finish, because it wasn't captured by
|
|
* btrfs_get_logged_extents().
|
|
*/
|
|
ret = start_ordered_ops(inode, start, end);
|
|
}
|
|
if (ret) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
atomic_inc(&root->log_batch);
|
|
|
|
/*
|
|
* If the last transaction that changed this file was before the current
|
|
* transaction and we have the full sync flag set in our inode, we can
|
|
* bail out now without any syncing.
|
|
*
|
|
* Note that we can't bail out if the full sync flag isn't set. This is
|
|
* because when the full sync flag is set we start all ordered extents
|
|
* and wait for them to fully complete - when they complete they update
|
|
* the inode's last_trans field through:
|
|
*
|
|
* btrfs_finish_ordered_io() ->
|
|
* btrfs_update_inode_fallback() ->
|
|
* btrfs_update_inode() ->
|
|
* btrfs_set_inode_last_trans()
|
|
*
|
|
* So we are sure that last_trans is up to date and can do this check to
|
|
* bail out safely. For the fast path, when the full sync flag is not
|
|
* set in our inode, we can not do it because we start only our ordered
|
|
* extents and don't wait for them to complete (that is when
|
|
* btrfs_finish_ordered_io runs), so here at this point their last_trans
|
|
* value might be less than or equals to fs_info->last_trans_committed,
|
|
* and setting a speculative last_trans for an inode when a buffered
|
|
* write is made (such as fs_info->generation + 1 for example) would not
|
|
* be reliable since after setting the value and before fsync is called
|
|
* any number of transactions can start and commit (transaction kthread
|
|
* commits the current transaction periodically), and a transaction
|
|
* commit does not start nor waits for ordered extents to complete.
|
|
*/
|
|
smp_mb();
|
|
if (btrfs_inode_in_log(inode, root->fs_info->generation) ||
|
|
(BTRFS_I(inode)->last_trans <=
|
|
root->fs_info->last_trans_committed &&
|
|
(full_sync ||
|
|
!btrfs_have_ordered_extents_in_range(inode, start, len)))) {
|
|
/*
|
|
* We'v had everything committed since the last time we were
|
|
* modified so clear this flag in case it was set for whatever
|
|
* reason, it's no longer relevant.
|
|
*/
|
|
clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
|
|
&BTRFS_I(inode)->runtime_flags);
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* ok we haven't committed the transaction yet, lets do a commit
|
|
*/
|
|
if (file->private_data)
|
|
btrfs_ioctl_trans_end(file);
|
|
|
|
/*
|
|
* We use start here because we will need to wait on the IO to complete
|
|
* in btrfs_sync_log, which could require joining a transaction (for
|
|
* example checking cross references in the nocow path). If we use join
|
|
* here we could get into a situation where we're waiting on IO to
|
|
* happen that is blocked on a transaction trying to commit. With start
|
|
* we inc the extwriter counter, so we wait for all extwriters to exit
|
|
* before we start blocking join'ers. This comment is to keep somebody
|
|
* from thinking they are super smart and changing this to
|
|
* btrfs_join_transaction *cough*Josef*cough*.
|
|
*/
|
|
trans = btrfs_start_transaction(root, 0);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
trans->sync = true;
|
|
|
|
btrfs_init_log_ctx(&ctx);
|
|
|
|
ret = btrfs_log_dentry_safe(trans, root, dentry, start, end, &ctx);
|
|
if (ret < 0) {
|
|
/* Fallthrough and commit/free transaction. */
|
|
ret = 1;
|
|
}
|
|
|
|
/* we've logged all the items and now have a consistent
|
|
* version of the file in the log. It is possible that
|
|
* someone will come in and modify the file, but that's
|
|
* fine because the log is consistent on disk, and we
|
|
* have references to all of the file's extents
|
|
*
|
|
* It is possible that someone will come in and log the
|
|
* file again, but that will end up using the synchronization
|
|
* inside btrfs_sync_log to keep things safe.
|
|
*/
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
/*
|
|
* If any of the ordered extents had an error, just return it to user
|
|
* space, so that the application knows some writes didn't succeed and
|
|
* can take proper action (retry for e.g.). Blindly committing the
|
|
* transaction in this case, would fool userspace that everything was
|
|
* successful. And we also want to make sure our log doesn't contain
|
|
* file extent items pointing to extents that weren't fully written to -
|
|
* just like in the non fast fsync path, where we check for the ordered
|
|
* operation's error flag before writing to the log tree and return -EIO
|
|
* if any of them had this flag set (btrfs_wait_ordered_range) -
|
|
* therefore we need to check for errors in the ordered operations,
|
|
* which are indicated by ctx.io_err.
|
|
*/
|
|
if (ctx.io_err) {
|
|
btrfs_end_transaction(trans, root);
|
|
ret = ctx.io_err;
|
|
goto out;
|
|
}
|
|
|
|
if (ret != BTRFS_NO_LOG_SYNC) {
|
|
if (!ret) {
|
|
ret = btrfs_sync_log(trans, root, &ctx);
|
|
if (!ret) {
|
|
ret = btrfs_end_transaction(trans, root);
|
|
goto out;
|
|
}
|
|
}
|
|
if (!full_sync) {
|
|
ret = btrfs_wait_ordered_range(inode, start,
|
|
end - start + 1);
|
|
if (ret) {
|
|
btrfs_end_transaction(trans, root);
|
|
goto out;
|
|
}
|
|
}
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
} else {
|
|
ret = btrfs_end_transaction(trans, root);
|
|
}
|
|
out:
|
|
return ret > 0 ? -EIO : ret;
|
|
}
|
|
|
|
static const struct vm_operations_struct btrfs_file_vm_ops = {
|
|
.fault = filemap_fault,
|
|
.map_pages = filemap_map_pages,
|
|
.page_mkwrite = btrfs_page_mkwrite,
|
|
};
|
|
|
|
static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
struct address_space *mapping = filp->f_mapping;
|
|
|
|
if (!mapping->a_ops->readpage)
|
|
return -ENOEXEC;
|
|
|
|
file_accessed(filp);
|
|
vma->vm_ops = &btrfs_file_vm_ops;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int hole_mergeable(struct inode *inode, struct extent_buffer *leaf,
|
|
int slot, u64 start, u64 end)
|
|
{
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
|
|
if (slot < 0 || slot >= btrfs_header_nritems(leaf))
|
|
return 0;
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, slot);
|
|
if (key.objectid != btrfs_ino(inode) ||
|
|
key.type != BTRFS_EXTENT_DATA_KEY)
|
|
return 0;
|
|
|
|
fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
|
|
|
|
if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
|
|
return 0;
|
|
|
|
if (btrfs_file_extent_disk_bytenr(leaf, fi))
|
|
return 0;
|
|
|
|
if (key.offset == end)
|
|
return 1;
|
|
if (key.offset + btrfs_file_extent_num_bytes(leaf, fi) == start)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int fill_holes(struct btrfs_trans_handle *trans, struct inode *inode,
|
|
struct btrfs_path *path, u64 offset, u64 end)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct extent_map *hole_em;
|
|
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
|
|
struct btrfs_key key;
|
|
int ret;
|
|
|
|
if (btrfs_fs_incompat(root->fs_info, NO_HOLES))
|
|
goto out;
|
|
|
|
key.objectid = btrfs_ino(inode);
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
key.offset = offset;
|
|
|
|
ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
BUG_ON(!ret);
|
|
|
|
leaf = path->nodes[0];
|
|
if (hole_mergeable(inode, leaf, path->slots[0]-1, offset, end)) {
|
|
u64 num_bytes;
|
|
|
|
path->slots[0]--;
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
num_bytes = btrfs_file_extent_num_bytes(leaf, fi) +
|
|
end - offset;
|
|
btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
|
|
btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
|
|
btrfs_set_file_extent_offset(leaf, fi, 0);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
goto out;
|
|
}
|
|
|
|
if (hole_mergeable(inode, leaf, path->slots[0], offset, end)) {
|
|
u64 num_bytes;
|
|
|
|
key.offset = offset;
|
|
btrfs_set_item_key_safe(root->fs_info, path, &key);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end -
|
|
offset;
|
|
btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
|
|
btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
|
|
btrfs_set_file_extent_offset(leaf, fi, 0);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
goto out;
|
|
}
|
|
btrfs_release_path(path);
|
|
|
|
ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset,
|
|
0, 0, end - offset, 0, end - offset,
|
|
0, 0, 0);
|
|
if (ret)
|
|
return ret;
|
|
|
|
out:
|
|
btrfs_release_path(path);
|
|
|
|
hole_em = alloc_extent_map();
|
|
if (!hole_em) {
|
|
btrfs_drop_extent_cache(inode, offset, end - 1, 0);
|
|
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
|
|
&BTRFS_I(inode)->runtime_flags);
|
|
} else {
|
|
hole_em->start = offset;
|
|
hole_em->len = end - offset;
|
|
hole_em->ram_bytes = hole_em->len;
|
|
hole_em->orig_start = offset;
|
|
|
|
hole_em->block_start = EXTENT_MAP_HOLE;
|
|
hole_em->block_len = 0;
|
|
hole_em->orig_block_len = 0;
|
|
hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
|
|
hole_em->compress_type = BTRFS_COMPRESS_NONE;
|
|
hole_em->generation = trans->transid;
|
|
|
|
do {
|
|
btrfs_drop_extent_cache(inode, offset, end - 1, 0);
|
|
write_lock(&em_tree->lock);
|
|
ret = add_extent_mapping(em_tree, hole_em, 1);
|
|
write_unlock(&em_tree->lock);
|
|
} while (ret == -EEXIST);
|
|
free_extent_map(hole_em);
|
|
if (ret)
|
|
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
|
|
&BTRFS_I(inode)->runtime_flags);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Find a hole extent on given inode and change start/len to the end of hole
|
|
* extent.(hole/vacuum extent whose em->start <= start &&
|
|
* em->start + em->len > start)
|
|
* When a hole extent is found, return 1 and modify start/len.
|
|
*/
|
|
static int find_first_non_hole(struct inode *inode, u64 *start, u64 *len)
|
|
{
|
|
struct extent_map *em;
|
|
int ret = 0;
|
|
|
|
em = btrfs_get_extent(inode, NULL, 0, *start, *len, 0);
|
|
if (IS_ERR_OR_NULL(em)) {
|
|
if (!em)
|
|
ret = -ENOMEM;
|
|
else
|
|
ret = PTR_ERR(em);
|
|
return ret;
|
|
}
|
|
|
|
/* Hole or vacuum extent(only exists in no-hole mode) */
|
|
if (em->block_start == EXTENT_MAP_HOLE) {
|
|
ret = 1;
|
|
*len = em->start + em->len > *start + *len ?
|
|
0 : *start + *len - em->start - em->len;
|
|
*start = em->start + em->len;
|
|
}
|
|
free_extent_map(em);
|
|
return ret;
|
|
}
|
|
|
|
static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_state *cached_state = NULL;
|
|
struct btrfs_path *path;
|
|
struct btrfs_block_rsv *rsv;
|
|
struct btrfs_trans_handle *trans;
|
|
u64 lockstart;
|
|
u64 lockend;
|
|
u64 tail_start;
|
|
u64 tail_len;
|
|
u64 orig_start = offset;
|
|
u64 cur_offset;
|
|
u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
|
|
u64 drop_end;
|
|
int ret = 0;
|
|
int err = 0;
|
|
int rsv_count;
|
|
bool same_page;
|
|
bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES);
|
|
u64 ino_size;
|
|
bool truncated_page = false;
|
|
bool updated_inode = false;
|
|
|
|
ret = btrfs_wait_ordered_range(inode, offset, len);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
ino_size = round_up(inode->i_size, PAGE_CACHE_SIZE);
|
|
ret = find_first_non_hole(inode, &offset, &len);
|
|
if (ret < 0)
|
|
goto out_only_mutex;
|
|
if (ret && !len) {
|
|
/* Already in a large hole */
|
|
ret = 0;
|
|
goto out_only_mutex;
|
|
}
|
|
|
|
lockstart = round_up(offset, BTRFS_I(inode)->root->sectorsize);
|
|
lockend = round_down(offset + len,
|
|
BTRFS_I(inode)->root->sectorsize) - 1;
|
|
same_page = ((offset >> PAGE_CACHE_SHIFT) ==
|
|
((offset + len - 1) >> PAGE_CACHE_SHIFT));
|
|
|
|
/*
|
|
* We needn't truncate any page which is beyond the end of the file
|
|
* because we are sure there is no data there.
|
|
*/
|
|
/*
|
|
* Only do this if we are in the same page and we aren't doing the
|
|
* entire page.
|
|
*/
|
|
if (same_page && len < PAGE_CACHE_SIZE) {
|
|
if (offset < ino_size) {
|
|
truncated_page = true;
|
|
ret = btrfs_truncate_page(inode, offset, len, 0);
|
|
} else {
|
|
ret = 0;
|
|
}
|
|
goto out_only_mutex;
|
|
}
|
|
|
|
/* zero back part of the first page */
|
|
if (offset < ino_size) {
|
|
truncated_page = true;
|
|
ret = btrfs_truncate_page(inode, offset, 0, 0);
|
|
if (ret) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Check the aligned pages after the first unaligned page,
|
|
* if offset != orig_start, which means the first unaligned page
|
|
* including serveral following pages are already in holes,
|
|
* the extra check can be skipped */
|
|
if (offset == orig_start) {
|
|
/* after truncate page, check hole again */
|
|
len = offset + len - lockstart;
|
|
offset = lockstart;
|
|
ret = find_first_non_hole(inode, &offset, &len);
|
|
if (ret < 0)
|
|
goto out_only_mutex;
|
|
if (ret && !len) {
|
|
ret = 0;
|
|
goto out_only_mutex;
|
|
}
|
|
lockstart = offset;
|
|
}
|
|
|
|
/* Check the tail unaligned part is in a hole */
|
|
tail_start = lockend + 1;
|
|
tail_len = offset + len - tail_start;
|
|
if (tail_len) {
|
|
ret = find_first_non_hole(inode, &tail_start, &tail_len);
|
|
if (unlikely(ret < 0))
|
|
goto out_only_mutex;
|
|
if (!ret) {
|
|
/* zero the front end of the last page */
|
|
if (tail_start + tail_len < ino_size) {
|
|
truncated_page = true;
|
|
ret = btrfs_truncate_page(inode,
|
|
tail_start + tail_len, 0, 1);
|
|
if (ret)
|
|
goto out_only_mutex;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (lockend < lockstart) {
|
|
ret = 0;
|
|
goto out_only_mutex;
|
|
}
|
|
|
|
while (1) {
|
|
struct btrfs_ordered_extent *ordered;
|
|
|
|
truncate_pagecache_range(inode, lockstart, lockend);
|
|
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
|
|
0, &cached_state);
|
|
ordered = btrfs_lookup_first_ordered_extent(inode, lockend);
|
|
|
|
/*
|
|
* We need to make sure we have no ordered extents in this range
|
|
* and nobody raced in and read a page in this range, if we did
|
|
* we need to try again.
|
|
*/
|
|
if ((!ordered ||
|
|
(ordered->file_offset + ordered->len <= lockstart ||
|
|
ordered->file_offset > lockend)) &&
|
|
!btrfs_page_exists_in_range(inode, lockstart, lockend)) {
|
|
if (ordered)
|
|
btrfs_put_ordered_extent(ordered);
|
|
break;
|
|
}
|
|
if (ordered)
|
|
btrfs_put_ordered_extent(ordered);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
|
|
lockend, &cached_state, GFP_NOFS);
|
|
ret = btrfs_wait_ordered_range(inode, lockstart,
|
|
lockend - lockstart + 1);
|
|
if (ret) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP);
|
|
if (!rsv) {
|
|
ret = -ENOMEM;
|
|
goto out_free;
|
|
}
|
|
rsv->size = btrfs_calc_trunc_metadata_size(root, 1);
|
|
rsv->failfast = 1;
|
|
|
|
/*
|
|
* 1 - update the inode
|
|
* 1 - removing the extents in the range
|
|
* 1 - adding the hole extent if no_holes isn't set
|
|
*/
|
|
rsv_count = no_holes ? 2 : 3;
|
|
trans = btrfs_start_transaction(root, rsv_count);
|
|
if (IS_ERR(trans)) {
|
|
err = PTR_ERR(trans);
|
|
goto out_free;
|
|
}
|
|
|
|
ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
|
|
min_size);
|
|
BUG_ON(ret);
|
|
trans->block_rsv = rsv;
|
|
|
|
cur_offset = lockstart;
|
|
len = lockend - cur_offset;
|
|
while (cur_offset < lockend) {
|
|
ret = __btrfs_drop_extents(trans, root, inode, path,
|
|
cur_offset, lockend + 1,
|
|
&drop_end, 1, 0, 0, NULL);
|
|
if (ret != -ENOSPC)
|
|
break;
|
|
|
|
trans->block_rsv = &root->fs_info->trans_block_rsv;
|
|
|
|
if (cur_offset < ino_size) {
|
|
ret = fill_holes(trans, inode, path, cur_offset,
|
|
drop_end);
|
|
if (ret) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
}
|
|
|
|
cur_offset = drop_end;
|
|
|
|
ret = btrfs_update_inode(trans, root, inode);
|
|
if (ret) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
|
|
btrfs_end_transaction(trans, root);
|
|
btrfs_btree_balance_dirty(root);
|
|
|
|
trans = btrfs_start_transaction(root, rsv_count);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
trans = NULL;
|
|
break;
|
|
}
|
|
|
|
ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv,
|
|
rsv, min_size);
|
|
BUG_ON(ret); /* shouldn't happen */
|
|
trans->block_rsv = rsv;
|
|
|
|
ret = find_first_non_hole(inode, &cur_offset, &len);
|
|
if (unlikely(ret < 0))
|
|
break;
|
|
if (ret && !len) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (ret) {
|
|
err = ret;
|
|
goto out_trans;
|
|
}
|
|
|
|
trans->block_rsv = &root->fs_info->trans_block_rsv;
|
|
/*
|
|
* Don't insert file hole extent item if it's for a range beyond eof
|
|
* (because it's useless) or if it represents a 0 bytes range (when
|
|
* cur_offset == drop_end).
|
|
*/
|
|
if (cur_offset < ino_size && cur_offset < drop_end) {
|
|
ret = fill_holes(trans, inode, path, cur_offset, drop_end);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out_trans;
|
|
}
|
|
}
|
|
|
|
out_trans:
|
|
if (!trans)
|
|
goto out_free;
|
|
|
|
inode_inc_iversion(inode);
|
|
inode->i_mtime = inode->i_ctime = CURRENT_TIME;
|
|
|
|
trans->block_rsv = &root->fs_info->trans_block_rsv;
|
|
ret = btrfs_update_inode(trans, root, inode);
|
|
updated_inode = true;
|
|
btrfs_end_transaction(trans, root);
|
|
btrfs_btree_balance_dirty(root);
|
|
out_free:
|
|
btrfs_free_path(path);
|
|
btrfs_free_block_rsv(root, rsv);
|
|
out:
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
|
|
&cached_state, GFP_NOFS);
|
|
out_only_mutex:
|
|
if (!updated_inode && truncated_page && !ret && !err) {
|
|
/*
|
|
* If we only end up zeroing part of a page, we still need to
|
|
* update the inode item, so that all the time fields are
|
|
* updated as well as the necessary btrfs inode in memory fields
|
|
* for detecting, at fsync time, if the inode isn't yet in the
|
|
* log tree or it's there but not up to date.
|
|
*/
|
|
trans = btrfs_start_transaction(root, 1);
|
|
if (IS_ERR(trans)) {
|
|
err = PTR_ERR(trans);
|
|
} else {
|
|
err = btrfs_update_inode(trans, root, inode);
|
|
ret = btrfs_end_transaction(trans, root);
|
|
}
|
|
}
|
|
mutex_unlock(&inode->i_mutex);
|
|
if (ret && !err)
|
|
err = ret;
|
|
return err;
|
|
}
|
|
|
|
static long btrfs_fallocate(struct file *file, int mode,
|
|
loff_t offset, loff_t len)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct extent_state *cached_state = NULL;
|
|
u64 cur_offset;
|
|
u64 last_byte;
|
|
u64 alloc_start;
|
|
u64 alloc_end;
|
|
u64 alloc_hint = 0;
|
|
u64 locked_end;
|
|
struct extent_map *em;
|
|
int blocksize = BTRFS_I(inode)->root->sectorsize;
|
|
int ret;
|
|
|
|
alloc_start = round_down(offset, blocksize);
|
|
alloc_end = round_up(offset + len, blocksize);
|
|
|
|
/* Make sure we aren't being give some crap mode */
|
|
if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (mode & FALLOC_FL_PUNCH_HOLE)
|
|
return btrfs_punch_hole(inode, offset, len);
|
|
|
|
/*
|
|
* Make sure we have enough space before we do the
|
|
* allocation.
|
|
*/
|
|
ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start, alloc_end - alloc_start);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
ret = inode_newsize_ok(inode, alloc_end);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if (alloc_start > inode->i_size) {
|
|
ret = btrfs_cont_expand(inode, i_size_read(inode),
|
|
alloc_start);
|
|
if (ret)
|
|
goto out;
|
|
} else {
|
|
/*
|
|
* If we are fallocating from the end of the file onward we
|
|
* need to zero out the end of the page if i_size lands in the
|
|
* middle of a page.
|
|
*/
|
|
ret = btrfs_truncate_page(inode, inode->i_size, 0, 0);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* wait for ordered IO before we have any locks. We'll loop again
|
|
* below with the locks held.
|
|
*/
|
|
ret = btrfs_wait_ordered_range(inode, alloc_start,
|
|
alloc_end - alloc_start);
|
|
if (ret)
|
|
goto out;
|
|
|
|
locked_end = alloc_end - 1;
|
|
while (1) {
|
|
struct btrfs_ordered_extent *ordered;
|
|
|
|
/* the extent lock is ordered inside the running
|
|
* transaction
|
|
*/
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
|
|
locked_end, 0, &cached_state);
|
|
ordered = btrfs_lookup_first_ordered_extent(inode,
|
|
alloc_end - 1);
|
|
if (ordered &&
|
|
ordered->file_offset + ordered->len > alloc_start &&
|
|
ordered->file_offset < alloc_end) {
|
|
btrfs_put_ordered_extent(ordered);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
|
|
alloc_start, locked_end,
|
|
&cached_state, GFP_NOFS);
|
|
/*
|
|
* we can't wait on the range with the transaction
|
|
* running or with the extent lock held
|
|
*/
|
|
ret = btrfs_wait_ordered_range(inode, alloc_start,
|
|
alloc_end - alloc_start);
|
|
if (ret)
|
|
goto out;
|
|
} else {
|
|
if (ordered)
|
|
btrfs_put_ordered_extent(ordered);
|
|
break;
|
|
}
|
|
}
|
|
|
|
cur_offset = alloc_start;
|
|
while (1) {
|
|
u64 actual_end;
|
|
|
|
em = btrfs_get_extent(inode, NULL, 0, cur_offset,
|
|
alloc_end - cur_offset, 0);
|
|
if (IS_ERR_OR_NULL(em)) {
|
|
if (!em)
|
|
ret = -ENOMEM;
|
|
else
|
|
ret = PTR_ERR(em);
|
|
break;
|
|
}
|
|
last_byte = min(extent_map_end(em), alloc_end);
|
|
actual_end = min_t(u64, extent_map_end(em), offset + len);
|
|
last_byte = ALIGN(last_byte, blocksize);
|
|
|
|
if (em->block_start == EXTENT_MAP_HOLE ||
|
|
(cur_offset >= inode->i_size &&
|
|
!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
|
|
ret = btrfs_prealloc_file_range(inode, mode, cur_offset,
|
|
last_byte - cur_offset,
|
|
1 << inode->i_blkbits,
|
|
offset + len,
|
|
&alloc_hint);
|
|
} else if (actual_end > inode->i_size &&
|
|
!(mode & FALLOC_FL_KEEP_SIZE)) {
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
|
|
/*
|
|
* We didn't need to allocate any more space, but we
|
|
* still extended the size of the file so we need to
|
|
* update i_size and the inode item.
|
|
*/
|
|
trans = btrfs_start_transaction(root, 1);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
} else {
|
|
inode->i_ctime = CURRENT_TIME;
|
|
i_size_write(inode, actual_end);
|
|
btrfs_ordered_update_i_size(inode, actual_end,
|
|
NULL);
|
|
ret = btrfs_update_inode(trans, root, inode);
|
|
if (ret)
|
|
btrfs_end_transaction(trans, root);
|
|
else
|
|
ret = btrfs_end_transaction(trans,
|
|
root);
|
|
}
|
|
}
|
|
free_extent_map(em);
|
|
if (ret < 0)
|
|
break;
|
|
|
|
cur_offset = last_byte;
|
|
if (cur_offset >= alloc_end) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
}
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
|
|
&cached_state, GFP_NOFS);
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
/* Let go of our reservation. */
|
|
btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
|
|
return ret;
|
|
}
|
|
|
|
static int find_desired_extent(struct inode *inode, loff_t *offset, int whence)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_map *em = NULL;
|
|
struct extent_state *cached_state = NULL;
|
|
u64 lockstart;
|
|
u64 lockend;
|
|
u64 start;
|
|
u64 len;
|
|
int ret = 0;
|
|
|
|
if (inode->i_size == 0)
|
|
return -ENXIO;
|
|
|
|
/*
|
|
* *offset can be negative, in this case we start finding DATA/HOLE from
|
|
* the very start of the file.
|
|
*/
|
|
start = max_t(loff_t, 0, *offset);
|
|
|
|
lockstart = round_down(start, root->sectorsize);
|
|
lockend = round_up(i_size_read(inode), root->sectorsize);
|
|
if (lockend <= lockstart)
|
|
lockend = lockstart + root->sectorsize;
|
|
lockend--;
|
|
len = lockend - lockstart + 1;
|
|
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0,
|
|
&cached_state);
|
|
|
|
while (start < inode->i_size) {
|
|
em = btrfs_get_extent_fiemap(inode, NULL, 0, start, len, 0);
|
|
if (IS_ERR(em)) {
|
|
ret = PTR_ERR(em);
|
|
em = NULL;
|
|
break;
|
|
}
|
|
|
|
if (whence == SEEK_HOLE &&
|
|
(em->block_start == EXTENT_MAP_HOLE ||
|
|
test_bit(EXTENT_FLAG_PREALLOC, &em->flags)))
|
|
break;
|
|
else if (whence == SEEK_DATA &&
|
|
(em->block_start != EXTENT_MAP_HOLE &&
|
|
!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)))
|
|
break;
|
|
|
|
start = em->start + em->len;
|
|
free_extent_map(em);
|
|
em = NULL;
|
|
cond_resched();
|
|
}
|
|
free_extent_map(em);
|
|
if (!ret) {
|
|
if (whence == SEEK_DATA && start >= inode->i_size)
|
|
ret = -ENXIO;
|
|
else
|
|
*offset = min_t(loff_t, start, inode->i_size);
|
|
}
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
|
|
&cached_state, GFP_NOFS);
|
|
return ret;
|
|
}
|
|
|
|
static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence)
|
|
{
|
|
struct inode *inode = file->f_mapping->host;
|
|
int ret;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
switch (whence) {
|
|
case SEEK_END:
|
|
case SEEK_CUR:
|
|
offset = generic_file_llseek(file, offset, whence);
|
|
goto out;
|
|
case SEEK_DATA:
|
|
case SEEK_HOLE:
|
|
if (offset >= i_size_read(inode)) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return -ENXIO;
|
|
}
|
|
|
|
ret = find_desired_extent(inode, &offset, whence);
|
|
if (ret) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
return offset;
|
|
}
|
|
|
|
const struct file_operations btrfs_file_operations = {
|
|
.llseek = btrfs_file_llseek,
|
|
.read_iter = generic_file_read_iter,
|
|
.splice_read = generic_file_splice_read,
|
|
.write_iter = btrfs_file_write_iter,
|
|
.mmap = btrfs_file_mmap,
|
|
.open = generic_file_open,
|
|
.release = btrfs_release_file,
|
|
.fsync = btrfs_sync_file,
|
|
.fallocate = btrfs_fallocate,
|
|
.unlocked_ioctl = btrfs_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = btrfs_ioctl,
|
|
#endif
|
|
};
|
|
|
|
void btrfs_auto_defrag_exit(void)
|
|
{
|
|
if (btrfs_inode_defrag_cachep)
|
|
kmem_cache_destroy(btrfs_inode_defrag_cachep);
|
|
}
|
|
|
|
int btrfs_auto_defrag_init(void)
|
|
{
|
|
btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag",
|
|
sizeof(struct inode_defrag), 0,
|
|
SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
|
|
NULL);
|
|
if (!btrfs_inode_defrag_cachep)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int btrfs_fdatawrite_range(struct inode *inode, loff_t start, loff_t end)
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* So with compression we will find and lock a dirty page and clear the
|
|
* first one as dirty, setup an async extent, and immediately return
|
|
* with the entire range locked but with nobody actually marked with
|
|
* writeback. So we can't just filemap_write_and_wait_range() and
|
|
* expect it to work since it will just kick off a thread to do the
|
|
* actual work. So we need to call filemap_fdatawrite_range _again_
|
|
* since it will wait on the page lock, which won't be unlocked until
|
|
* after the pages have been marked as writeback and so we're good to go
|
|
* from there. We have to do this otherwise we'll miss the ordered
|
|
* extents and that results in badness. Please Josef, do not think you
|
|
* know better and pull this out at some point in the future, it is
|
|
* right and you are wrong.
|
|
*/
|
|
ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
|
|
if (!ret && test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
|
|
&BTRFS_I(inode)->runtime_flags))
|
|
ret = filemap_fdatawrite_range(inode->i_mapping, start, end);
|
|
|
|
return ret;
|
|
}
|