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147d256e09
These arguments are not used in functions, remove them for cleanup and make kernel stack happy. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
4667 lines
110 KiB
C
4667 lines
110 KiB
C
/*
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* Copyright (C) 2009 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/sched.h>
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#include <linux/pagemap.h>
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#include <linux/writeback.h>
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#include <linux/blkdev.h>
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#include <linux/rbtree.h>
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#include <linux/slab.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 "volumes.h"
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#include "locking.h"
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#include "btrfs_inode.h"
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#include "async-thread.h"
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#include "free-space-cache.h"
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#include "inode-map.h"
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/*
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* backref_node, mapping_node and tree_block start with this
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*/
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struct tree_entry {
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struct rb_node rb_node;
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u64 bytenr;
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};
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/*
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* present a tree block in the backref cache
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*/
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struct backref_node {
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struct rb_node rb_node;
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u64 bytenr;
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u64 new_bytenr;
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/* objectid of tree block owner, can be not uptodate */
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u64 owner;
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/* link to pending, changed or detached list */
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struct list_head list;
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/* list of upper level blocks reference this block */
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struct list_head upper;
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/* list of child blocks in the cache */
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struct list_head lower;
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/* NULL if this node is not tree root */
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struct btrfs_root *root;
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/* extent buffer got by COW the block */
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struct extent_buffer *eb;
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/* level of tree block */
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unsigned int level:8;
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/* is the block in non-reference counted tree */
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unsigned int cowonly:1;
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/* 1 if no child node in the cache */
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unsigned int lowest:1;
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/* is the extent buffer locked */
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unsigned int locked:1;
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/* has the block been processed */
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unsigned int processed:1;
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/* have backrefs of this block been checked */
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unsigned int checked:1;
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/*
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* 1 if corresponding block has been cowed but some upper
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* level block pointers may not point to the new location
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*/
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unsigned int pending:1;
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/*
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* 1 if the backref node isn't connected to any other
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* backref node.
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*/
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unsigned int detached:1;
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};
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/*
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* present a block pointer in the backref cache
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*/
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struct backref_edge {
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struct list_head list[2];
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struct backref_node *node[2];
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};
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#define LOWER 0
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#define UPPER 1
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#define RELOCATION_RESERVED_NODES 256
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struct backref_cache {
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/* red black tree of all backref nodes in the cache */
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struct rb_root rb_root;
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/* for passing backref nodes to btrfs_reloc_cow_block */
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struct backref_node *path[BTRFS_MAX_LEVEL];
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/*
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* list of blocks that have been cowed but some block
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* pointers in upper level blocks may not reflect the
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* new location
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*/
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struct list_head pending[BTRFS_MAX_LEVEL];
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/* list of backref nodes with no child node */
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struct list_head leaves;
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/* list of blocks that have been cowed in current transaction */
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struct list_head changed;
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/* list of detached backref node. */
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struct list_head detached;
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u64 last_trans;
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int nr_nodes;
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int nr_edges;
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};
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/*
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* map address of tree root to tree
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*/
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struct mapping_node {
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struct rb_node rb_node;
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u64 bytenr;
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void *data;
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};
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struct mapping_tree {
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struct rb_root rb_root;
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spinlock_t lock;
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};
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/*
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* present a tree block to process
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*/
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struct tree_block {
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struct rb_node rb_node;
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u64 bytenr;
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struct btrfs_key key;
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unsigned int level:8;
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unsigned int key_ready:1;
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};
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#define MAX_EXTENTS 128
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struct file_extent_cluster {
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u64 start;
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u64 end;
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u64 boundary[MAX_EXTENTS];
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unsigned int nr;
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};
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struct reloc_control {
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/* block group to relocate */
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struct btrfs_block_group_cache *block_group;
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/* extent tree */
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struct btrfs_root *extent_root;
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/* inode for moving data */
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struct inode *data_inode;
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struct btrfs_block_rsv *block_rsv;
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struct backref_cache backref_cache;
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struct file_extent_cluster cluster;
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/* tree blocks have been processed */
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struct extent_io_tree processed_blocks;
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/* map start of tree root to corresponding reloc tree */
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struct mapping_tree reloc_root_tree;
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/* list of reloc trees */
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struct list_head reloc_roots;
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/* size of metadata reservation for merging reloc trees */
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u64 merging_rsv_size;
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/* size of relocated tree nodes */
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u64 nodes_relocated;
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/* reserved size for block group relocation*/
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u64 reserved_bytes;
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u64 search_start;
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u64 extents_found;
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unsigned int stage:8;
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unsigned int create_reloc_tree:1;
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unsigned int merge_reloc_tree:1;
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unsigned int found_file_extent:1;
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};
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/* stages of data relocation */
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#define MOVE_DATA_EXTENTS 0
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#define UPDATE_DATA_PTRS 1
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static void remove_backref_node(struct backref_cache *cache,
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struct backref_node *node);
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static void __mark_block_processed(struct reloc_control *rc,
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struct backref_node *node);
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static void mapping_tree_init(struct mapping_tree *tree)
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{
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tree->rb_root = RB_ROOT;
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spin_lock_init(&tree->lock);
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}
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static void backref_cache_init(struct backref_cache *cache)
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{
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int i;
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cache->rb_root = RB_ROOT;
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for (i = 0; i < BTRFS_MAX_LEVEL; i++)
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INIT_LIST_HEAD(&cache->pending[i]);
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INIT_LIST_HEAD(&cache->changed);
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INIT_LIST_HEAD(&cache->detached);
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INIT_LIST_HEAD(&cache->leaves);
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}
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static void backref_cache_cleanup(struct backref_cache *cache)
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{
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struct backref_node *node;
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int i;
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while (!list_empty(&cache->detached)) {
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node = list_entry(cache->detached.next,
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struct backref_node, list);
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remove_backref_node(cache, node);
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}
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while (!list_empty(&cache->leaves)) {
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node = list_entry(cache->leaves.next,
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struct backref_node, lower);
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remove_backref_node(cache, node);
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}
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cache->last_trans = 0;
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for (i = 0; i < BTRFS_MAX_LEVEL; i++)
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BUG_ON(!list_empty(&cache->pending[i]));
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BUG_ON(!list_empty(&cache->changed));
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BUG_ON(!list_empty(&cache->detached));
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BUG_ON(!RB_EMPTY_ROOT(&cache->rb_root));
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BUG_ON(cache->nr_nodes);
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BUG_ON(cache->nr_edges);
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}
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static struct backref_node *alloc_backref_node(struct backref_cache *cache)
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{
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struct backref_node *node;
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node = kzalloc(sizeof(*node), GFP_NOFS);
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if (node) {
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INIT_LIST_HEAD(&node->list);
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INIT_LIST_HEAD(&node->upper);
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INIT_LIST_HEAD(&node->lower);
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RB_CLEAR_NODE(&node->rb_node);
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cache->nr_nodes++;
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}
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return node;
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}
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static void free_backref_node(struct backref_cache *cache,
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struct backref_node *node)
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{
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if (node) {
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cache->nr_nodes--;
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kfree(node);
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}
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}
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static struct backref_edge *alloc_backref_edge(struct backref_cache *cache)
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{
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struct backref_edge *edge;
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edge = kzalloc(sizeof(*edge), GFP_NOFS);
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if (edge)
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cache->nr_edges++;
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return edge;
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}
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static void free_backref_edge(struct backref_cache *cache,
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struct backref_edge *edge)
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{
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if (edge) {
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cache->nr_edges--;
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kfree(edge);
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}
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}
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static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr,
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struct rb_node *node)
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{
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struct rb_node **p = &root->rb_node;
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struct rb_node *parent = NULL;
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struct tree_entry *entry;
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while (*p) {
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parent = *p;
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entry = rb_entry(parent, struct tree_entry, rb_node);
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if (bytenr < entry->bytenr)
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p = &(*p)->rb_left;
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else if (bytenr > entry->bytenr)
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p = &(*p)->rb_right;
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else
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return parent;
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}
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rb_link_node(node, parent, p);
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rb_insert_color(node, root);
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return NULL;
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}
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static struct rb_node *tree_search(struct rb_root *root, u64 bytenr)
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{
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struct rb_node *n = root->rb_node;
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struct tree_entry *entry;
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while (n) {
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entry = rb_entry(n, struct tree_entry, rb_node);
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if (bytenr < entry->bytenr)
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n = n->rb_left;
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else if (bytenr > entry->bytenr)
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n = n->rb_right;
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else
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return n;
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}
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return NULL;
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}
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static void backref_tree_panic(struct rb_node *rb_node, int errno, u64 bytenr)
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{
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struct btrfs_fs_info *fs_info = NULL;
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struct backref_node *bnode = rb_entry(rb_node, struct backref_node,
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rb_node);
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if (bnode->root)
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fs_info = bnode->root->fs_info;
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btrfs_panic(fs_info, errno, "Inconsistency in backref cache "
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"found at offset %llu", bytenr);
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}
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/*
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* walk up backref nodes until reach node presents tree root
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*/
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static struct backref_node *walk_up_backref(struct backref_node *node,
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struct backref_edge *edges[],
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int *index)
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{
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struct backref_edge *edge;
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int idx = *index;
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while (!list_empty(&node->upper)) {
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edge = list_entry(node->upper.next,
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struct backref_edge, list[LOWER]);
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edges[idx++] = edge;
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node = edge->node[UPPER];
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}
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BUG_ON(node->detached);
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*index = idx;
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return node;
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}
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/*
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* walk down backref nodes to find start of next reference path
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*/
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static struct backref_node *walk_down_backref(struct backref_edge *edges[],
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int *index)
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{
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struct backref_edge *edge;
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struct backref_node *lower;
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int idx = *index;
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while (idx > 0) {
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edge = edges[idx - 1];
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lower = edge->node[LOWER];
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if (list_is_last(&edge->list[LOWER], &lower->upper)) {
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idx--;
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continue;
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}
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edge = list_entry(edge->list[LOWER].next,
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struct backref_edge, list[LOWER]);
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edges[idx - 1] = edge;
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*index = idx;
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return edge->node[UPPER];
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}
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*index = 0;
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return NULL;
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}
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static void unlock_node_buffer(struct backref_node *node)
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{
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if (node->locked) {
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btrfs_tree_unlock(node->eb);
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node->locked = 0;
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}
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}
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static void drop_node_buffer(struct backref_node *node)
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{
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if (node->eb) {
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unlock_node_buffer(node);
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free_extent_buffer(node->eb);
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node->eb = NULL;
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}
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}
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static void drop_backref_node(struct backref_cache *tree,
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struct backref_node *node)
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{
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BUG_ON(!list_empty(&node->upper));
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drop_node_buffer(node);
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list_del(&node->list);
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list_del(&node->lower);
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if (!RB_EMPTY_NODE(&node->rb_node))
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rb_erase(&node->rb_node, &tree->rb_root);
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free_backref_node(tree, node);
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}
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/*
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* remove a backref node from the backref cache
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*/
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static void remove_backref_node(struct backref_cache *cache,
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struct backref_node *node)
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{
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struct backref_node *upper;
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struct backref_edge *edge;
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if (!node)
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return;
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BUG_ON(!node->lowest && !node->detached);
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while (!list_empty(&node->upper)) {
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edge = list_entry(node->upper.next, struct backref_edge,
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list[LOWER]);
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upper = edge->node[UPPER];
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list_del(&edge->list[LOWER]);
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list_del(&edge->list[UPPER]);
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free_backref_edge(cache, edge);
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if (RB_EMPTY_NODE(&upper->rb_node)) {
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BUG_ON(!list_empty(&node->upper));
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drop_backref_node(cache, node);
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node = upper;
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node->lowest = 1;
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continue;
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}
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/*
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* add the node to leaf node list if no other
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* child block cached.
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*/
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if (list_empty(&upper->lower)) {
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list_add_tail(&upper->lower, &cache->leaves);
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upper->lowest = 1;
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}
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}
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drop_backref_node(cache, node);
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}
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static void update_backref_node(struct backref_cache *cache,
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struct backref_node *node, u64 bytenr)
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{
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struct rb_node *rb_node;
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rb_erase(&node->rb_node, &cache->rb_root);
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node->bytenr = bytenr;
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rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node);
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if (rb_node)
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backref_tree_panic(rb_node, -EEXIST, bytenr);
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}
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/*
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* update backref cache after a transaction commit
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*/
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static int update_backref_cache(struct btrfs_trans_handle *trans,
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struct backref_cache *cache)
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{
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struct backref_node *node;
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int level = 0;
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if (cache->last_trans == 0) {
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cache->last_trans = trans->transid;
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return 0;
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}
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if (cache->last_trans == trans->transid)
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return 0;
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|
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/*
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* detached nodes are used to avoid unnecessary backref
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* lookup. transaction commit changes the extent tree.
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* so the detached nodes are no longer useful.
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*/
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while (!list_empty(&cache->detached)) {
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node = list_entry(cache->detached.next,
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struct backref_node, list);
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remove_backref_node(cache, node);
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}
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while (!list_empty(&cache->changed)) {
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node = list_entry(cache->changed.next,
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struct backref_node, list);
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list_del_init(&node->list);
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BUG_ON(node->pending);
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update_backref_node(cache, node, node->new_bytenr);
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}
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|
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/*
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* some nodes can be left in the pending list if there were
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* errors during processing the pending nodes.
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|
*/
|
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for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
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list_for_each_entry(node, &cache->pending[level], list) {
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BUG_ON(!node->pending);
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if (node->bytenr == node->new_bytenr)
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continue;
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update_backref_node(cache, node, node->new_bytenr);
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}
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}
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cache->last_trans = 0;
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return 1;
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}
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|
|
|
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static int should_ignore_root(struct btrfs_root *root)
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{
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struct btrfs_root *reloc_root;
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|
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if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
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return 0;
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reloc_root = root->reloc_root;
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if (!reloc_root)
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return 0;
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if (btrfs_root_last_snapshot(&reloc_root->root_item) ==
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root->fs_info->running_transaction->transid - 1)
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return 0;
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/*
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* if there is reloc tree and it was created in previous
|
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* transaction backref lookup can find the reloc tree,
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* so backref node for the fs tree root is useless for
|
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* relocation.
|
|
*/
|
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return 1;
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}
|
|
/*
|
|
* find reloc tree by address of tree root
|
|
*/
|
|
static struct btrfs_root *find_reloc_root(struct reloc_control *rc,
|
|
u64 bytenr)
|
|
{
|
|
struct rb_node *rb_node;
|
|
struct mapping_node *node;
|
|
struct btrfs_root *root = NULL;
|
|
|
|
spin_lock(&rc->reloc_root_tree.lock);
|
|
rb_node = tree_search(&rc->reloc_root_tree.rb_root, bytenr);
|
|
if (rb_node) {
|
|
node = rb_entry(rb_node, struct mapping_node, rb_node);
|
|
root = (struct btrfs_root *)node->data;
|
|
}
|
|
spin_unlock(&rc->reloc_root_tree.lock);
|
|
return root;
|
|
}
|
|
|
|
static int is_cowonly_root(u64 root_objectid)
|
|
{
|
|
if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
|
|
root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
|
|
root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
|
|
root_objectid == BTRFS_DEV_TREE_OBJECTID ||
|
|
root_objectid == BTRFS_TREE_LOG_OBJECTID ||
|
|
root_objectid == BTRFS_CSUM_TREE_OBJECTID ||
|
|
root_objectid == BTRFS_UUID_TREE_OBJECTID ||
|
|
root_objectid == BTRFS_QUOTA_TREE_OBJECTID)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info,
|
|
u64 root_objectid)
|
|
{
|
|
struct btrfs_key key;
|
|
|
|
key.objectid = root_objectid;
|
|
key.type = BTRFS_ROOT_ITEM_KEY;
|
|
if (is_cowonly_root(root_objectid))
|
|
key.offset = 0;
|
|
else
|
|
key.offset = (u64)-1;
|
|
|
|
return btrfs_get_fs_root(fs_info, &key, false);
|
|
}
|
|
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
static noinline_for_stack
|
|
struct btrfs_root *find_tree_root(struct reloc_control *rc,
|
|
struct extent_buffer *leaf,
|
|
struct btrfs_extent_ref_v0 *ref0)
|
|
{
|
|
struct btrfs_root *root;
|
|
u64 root_objectid = btrfs_ref_root_v0(leaf, ref0);
|
|
u64 generation = btrfs_ref_generation_v0(leaf, ref0);
|
|
|
|
BUG_ON(root_objectid == BTRFS_TREE_RELOC_OBJECTID);
|
|
|
|
root = read_fs_root(rc->extent_root->fs_info, root_objectid);
|
|
BUG_ON(IS_ERR(root));
|
|
|
|
if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) &&
|
|
generation != btrfs_root_generation(&root->root_item))
|
|
return NULL;
|
|
|
|
return root;
|
|
}
|
|
#endif
|
|
|
|
static noinline_for_stack
|
|
int find_inline_backref(struct extent_buffer *leaf, int slot,
|
|
unsigned long *ptr, unsigned long *end)
|
|
{
|
|
struct btrfs_key key;
|
|
struct btrfs_extent_item *ei;
|
|
struct btrfs_tree_block_info *bi;
|
|
u32 item_size;
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, slot);
|
|
|
|
item_size = btrfs_item_size_nr(leaf, slot);
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
if (item_size < sizeof(*ei)) {
|
|
WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0));
|
|
return 1;
|
|
}
|
|
#endif
|
|
ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
|
|
WARN_ON(!(btrfs_extent_flags(leaf, ei) &
|
|
BTRFS_EXTENT_FLAG_TREE_BLOCK));
|
|
|
|
if (key.type == BTRFS_EXTENT_ITEM_KEY &&
|
|
item_size <= sizeof(*ei) + sizeof(*bi)) {
|
|
WARN_ON(item_size < sizeof(*ei) + sizeof(*bi));
|
|
return 1;
|
|
}
|
|
if (key.type == BTRFS_METADATA_ITEM_KEY &&
|
|
item_size <= sizeof(*ei)) {
|
|
WARN_ON(item_size < sizeof(*ei));
|
|
return 1;
|
|
}
|
|
|
|
if (key.type == BTRFS_EXTENT_ITEM_KEY) {
|
|
bi = (struct btrfs_tree_block_info *)(ei + 1);
|
|
*ptr = (unsigned long)(bi + 1);
|
|
} else {
|
|
*ptr = (unsigned long)(ei + 1);
|
|
}
|
|
*end = (unsigned long)ei + item_size;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* build backref tree for a given tree block. root of the backref tree
|
|
* corresponds the tree block, leaves of the backref tree correspond
|
|
* roots of b-trees that reference the tree block.
|
|
*
|
|
* the basic idea of this function is check backrefs of a given block
|
|
* to find upper level blocks that refernece the block, and then check
|
|
* bakcrefs of these upper level blocks recursively. the recursion stop
|
|
* when tree root is reached or backrefs for the block is cached.
|
|
*
|
|
* NOTE: if we find backrefs for a block are cached, we know backrefs
|
|
* for all upper level blocks that directly/indirectly reference the
|
|
* block are also cached.
|
|
*/
|
|
static noinline_for_stack
|
|
struct backref_node *build_backref_tree(struct reloc_control *rc,
|
|
struct btrfs_key *node_key,
|
|
int level, u64 bytenr)
|
|
{
|
|
struct backref_cache *cache = &rc->backref_cache;
|
|
struct btrfs_path *path1;
|
|
struct btrfs_path *path2;
|
|
struct extent_buffer *eb;
|
|
struct btrfs_root *root;
|
|
struct backref_node *cur;
|
|
struct backref_node *upper;
|
|
struct backref_node *lower;
|
|
struct backref_node *node = NULL;
|
|
struct backref_node *exist = NULL;
|
|
struct backref_edge *edge;
|
|
struct rb_node *rb_node;
|
|
struct btrfs_key key;
|
|
unsigned long end;
|
|
unsigned long ptr;
|
|
LIST_HEAD(list);
|
|
LIST_HEAD(useless);
|
|
int cowonly;
|
|
int ret;
|
|
int err = 0;
|
|
bool need_check = true;
|
|
|
|
path1 = btrfs_alloc_path();
|
|
path2 = btrfs_alloc_path();
|
|
if (!path1 || !path2) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
path1->reada = 1;
|
|
path2->reada = 2;
|
|
|
|
node = alloc_backref_node(cache);
|
|
if (!node) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
node->bytenr = bytenr;
|
|
node->level = level;
|
|
node->lowest = 1;
|
|
cur = node;
|
|
again:
|
|
end = 0;
|
|
ptr = 0;
|
|
key.objectid = cur->bytenr;
|
|
key.type = BTRFS_METADATA_ITEM_KEY;
|
|
key.offset = (u64)-1;
|
|
|
|
path1->search_commit_root = 1;
|
|
path1->skip_locking = 1;
|
|
ret = btrfs_search_slot(NULL, rc->extent_root, &key, path1,
|
|
0, 0);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
ASSERT(ret);
|
|
ASSERT(path1->slots[0]);
|
|
|
|
path1->slots[0]--;
|
|
|
|
WARN_ON(cur->checked);
|
|
if (!list_empty(&cur->upper)) {
|
|
/*
|
|
* the backref was added previously when processing
|
|
* backref of type BTRFS_TREE_BLOCK_REF_KEY
|
|
*/
|
|
ASSERT(list_is_singular(&cur->upper));
|
|
edge = list_entry(cur->upper.next, struct backref_edge,
|
|
list[LOWER]);
|
|
ASSERT(list_empty(&edge->list[UPPER]));
|
|
exist = edge->node[UPPER];
|
|
/*
|
|
* add the upper level block to pending list if we need
|
|
* check its backrefs
|
|
*/
|
|
if (!exist->checked)
|
|
list_add_tail(&edge->list[UPPER], &list);
|
|
} else {
|
|
exist = NULL;
|
|
}
|
|
|
|
while (1) {
|
|
cond_resched();
|
|
eb = path1->nodes[0];
|
|
|
|
if (ptr >= end) {
|
|
if (path1->slots[0] >= btrfs_header_nritems(eb)) {
|
|
ret = btrfs_next_leaf(rc->extent_root, path1);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
if (ret > 0)
|
|
break;
|
|
eb = path1->nodes[0];
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(eb, &key, path1->slots[0]);
|
|
if (key.objectid != cur->bytenr) {
|
|
WARN_ON(exist);
|
|
break;
|
|
}
|
|
|
|
if (key.type == BTRFS_EXTENT_ITEM_KEY ||
|
|
key.type == BTRFS_METADATA_ITEM_KEY) {
|
|
ret = find_inline_backref(eb, path1->slots[0],
|
|
&ptr, &end);
|
|
if (ret)
|
|
goto next;
|
|
}
|
|
}
|
|
|
|
if (ptr < end) {
|
|
/* update key for inline back ref */
|
|
struct btrfs_extent_inline_ref *iref;
|
|
iref = (struct btrfs_extent_inline_ref *)ptr;
|
|
key.type = btrfs_extent_inline_ref_type(eb, iref);
|
|
key.offset = btrfs_extent_inline_ref_offset(eb, iref);
|
|
WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY &&
|
|
key.type != BTRFS_SHARED_BLOCK_REF_KEY);
|
|
}
|
|
|
|
if (exist &&
|
|
((key.type == BTRFS_TREE_BLOCK_REF_KEY &&
|
|
exist->owner == key.offset) ||
|
|
(key.type == BTRFS_SHARED_BLOCK_REF_KEY &&
|
|
exist->bytenr == key.offset))) {
|
|
exist = NULL;
|
|
goto next;
|
|
}
|
|
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
if (key.type == BTRFS_SHARED_BLOCK_REF_KEY ||
|
|
key.type == BTRFS_EXTENT_REF_V0_KEY) {
|
|
if (key.type == BTRFS_EXTENT_REF_V0_KEY) {
|
|
struct btrfs_extent_ref_v0 *ref0;
|
|
ref0 = btrfs_item_ptr(eb, path1->slots[0],
|
|
struct btrfs_extent_ref_v0);
|
|
if (key.objectid == key.offset) {
|
|
root = find_tree_root(rc, eb, ref0);
|
|
if (root && !should_ignore_root(root))
|
|
cur->root = root;
|
|
else
|
|
list_add(&cur->list, &useless);
|
|
break;
|
|
}
|
|
if (is_cowonly_root(btrfs_ref_root_v0(eb,
|
|
ref0)))
|
|
cur->cowonly = 1;
|
|
}
|
|
#else
|
|
ASSERT(key.type != BTRFS_EXTENT_REF_V0_KEY);
|
|
if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
|
|
#endif
|
|
if (key.objectid == key.offset) {
|
|
/*
|
|
* only root blocks of reloc trees use
|
|
* backref of this type.
|
|
*/
|
|
root = find_reloc_root(rc, cur->bytenr);
|
|
ASSERT(root);
|
|
cur->root = root;
|
|
break;
|
|
}
|
|
|
|
edge = alloc_backref_edge(cache);
|
|
if (!edge) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
rb_node = tree_search(&cache->rb_root, key.offset);
|
|
if (!rb_node) {
|
|
upper = alloc_backref_node(cache);
|
|
if (!upper) {
|
|
free_backref_edge(cache, edge);
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
upper->bytenr = key.offset;
|
|
upper->level = cur->level + 1;
|
|
/*
|
|
* backrefs for the upper level block isn't
|
|
* cached, add the block to pending list
|
|
*/
|
|
list_add_tail(&edge->list[UPPER], &list);
|
|
} else {
|
|
upper = rb_entry(rb_node, struct backref_node,
|
|
rb_node);
|
|
ASSERT(upper->checked);
|
|
INIT_LIST_HEAD(&edge->list[UPPER]);
|
|
}
|
|
list_add_tail(&edge->list[LOWER], &cur->upper);
|
|
edge->node[LOWER] = cur;
|
|
edge->node[UPPER] = upper;
|
|
|
|
goto next;
|
|
} else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) {
|
|
goto next;
|
|
}
|
|
|
|
/* key.type == BTRFS_TREE_BLOCK_REF_KEY */
|
|
root = read_fs_root(rc->extent_root->fs_info, key.offset);
|
|
if (IS_ERR(root)) {
|
|
err = PTR_ERR(root);
|
|
goto out;
|
|
}
|
|
|
|
if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
|
|
cur->cowonly = 1;
|
|
|
|
if (btrfs_root_level(&root->root_item) == cur->level) {
|
|
/* tree root */
|
|
ASSERT(btrfs_root_bytenr(&root->root_item) ==
|
|
cur->bytenr);
|
|
if (should_ignore_root(root))
|
|
list_add(&cur->list, &useless);
|
|
else
|
|
cur->root = root;
|
|
break;
|
|
}
|
|
|
|
level = cur->level + 1;
|
|
|
|
/*
|
|
* searching the tree to find upper level blocks
|
|
* reference the block.
|
|
*/
|
|
path2->search_commit_root = 1;
|
|
path2->skip_locking = 1;
|
|
path2->lowest_level = level;
|
|
ret = btrfs_search_slot(NULL, root, node_key, path2, 0, 0);
|
|
path2->lowest_level = 0;
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
if (ret > 0 && path2->slots[level] > 0)
|
|
path2->slots[level]--;
|
|
|
|
eb = path2->nodes[level];
|
|
WARN_ON(btrfs_node_blockptr(eb, path2->slots[level]) !=
|
|
cur->bytenr);
|
|
|
|
lower = cur;
|
|
need_check = true;
|
|
for (; level < BTRFS_MAX_LEVEL; level++) {
|
|
if (!path2->nodes[level]) {
|
|
ASSERT(btrfs_root_bytenr(&root->root_item) ==
|
|
lower->bytenr);
|
|
if (should_ignore_root(root))
|
|
list_add(&lower->list, &useless);
|
|
else
|
|
lower->root = root;
|
|
break;
|
|
}
|
|
|
|
edge = alloc_backref_edge(cache);
|
|
if (!edge) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
eb = path2->nodes[level];
|
|
rb_node = tree_search(&cache->rb_root, eb->start);
|
|
if (!rb_node) {
|
|
upper = alloc_backref_node(cache);
|
|
if (!upper) {
|
|
free_backref_edge(cache, edge);
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
upper->bytenr = eb->start;
|
|
upper->owner = btrfs_header_owner(eb);
|
|
upper->level = lower->level + 1;
|
|
if (!test_bit(BTRFS_ROOT_REF_COWS,
|
|
&root->state))
|
|
upper->cowonly = 1;
|
|
|
|
/*
|
|
* if we know the block isn't shared
|
|
* we can void checking its backrefs.
|
|
*/
|
|
if (btrfs_block_can_be_shared(root, eb))
|
|
upper->checked = 0;
|
|
else
|
|
upper->checked = 1;
|
|
|
|
/*
|
|
* add the block to pending list if we
|
|
* need check its backrefs, we only do this once
|
|
* while walking up a tree as we will catch
|
|
* anything else later on.
|
|
*/
|
|
if (!upper->checked && need_check) {
|
|
need_check = false;
|
|
list_add_tail(&edge->list[UPPER],
|
|
&list);
|
|
} else {
|
|
if (upper->checked)
|
|
need_check = true;
|
|
INIT_LIST_HEAD(&edge->list[UPPER]);
|
|
}
|
|
} else {
|
|
upper = rb_entry(rb_node, struct backref_node,
|
|
rb_node);
|
|
ASSERT(upper->checked);
|
|
INIT_LIST_HEAD(&edge->list[UPPER]);
|
|
if (!upper->owner)
|
|
upper->owner = btrfs_header_owner(eb);
|
|
}
|
|
list_add_tail(&edge->list[LOWER], &lower->upper);
|
|
edge->node[LOWER] = lower;
|
|
edge->node[UPPER] = upper;
|
|
|
|
if (rb_node)
|
|
break;
|
|
lower = upper;
|
|
upper = NULL;
|
|
}
|
|
btrfs_release_path(path2);
|
|
next:
|
|
if (ptr < end) {
|
|
ptr += btrfs_extent_inline_ref_size(key.type);
|
|
if (ptr >= end) {
|
|
WARN_ON(ptr > end);
|
|
ptr = 0;
|
|
end = 0;
|
|
}
|
|
}
|
|
if (ptr >= end)
|
|
path1->slots[0]++;
|
|
}
|
|
btrfs_release_path(path1);
|
|
|
|
cur->checked = 1;
|
|
WARN_ON(exist);
|
|
|
|
/* the pending list isn't empty, take the first block to process */
|
|
if (!list_empty(&list)) {
|
|
edge = list_entry(list.next, struct backref_edge, list[UPPER]);
|
|
list_del_init(&edge->list[UPPER]);
|
|
cur = edge->node[UPPER];
|
|
goto again;
|
|
}
|
|
|
|
/*
|
|
* everything goes well, connect backref nodes and insert backref nodes
|
|
* into the cache.
|
|
*/
|
|
ASSERT(node->checked);
|
|
cowonly = node->cowonly;
|
|
if (!cowonly) {
|
|
rb_node = tree_insert(&cache->rb_root, node->bytenr,
|
|
&node->rb_node);
|
|
if (rb_node)
|
|
backref_tree_panic(rb_node, -EEXIST, node->bytenr);
|
|
list_add_tail(&node->lower, &cache->leaves);
|
|
}
|
|
|
|
list_for_each_entry(edge, &node->upper, list[LOWER])
|
|
list_add_tail(&edge->list[UPPER], &list);
|
|
|
|
while (!list_empty(&list)) {
|
|
edge = list_entry(list.next, struct backref_edge, list[UPPER]);
|
|
list_del_init(&edge->list[UPPER]);
|
|
upper = edge->node[UPPER];
|
|
if (upper->detached) {
|
|
list_del(&edge->list[LOWER]);
|
|
lower = edge->node[LOWER];
|
|
free_backref_edge(cache, edge);
|
|
if (list_empty(&lower->upper))
|
|
list_add(&lower->list, &useless);
|
|
continue;
|
|
}
|
|
|
|
if (!RB_EMPTY_NODE(&upper->rb_node)) {
|
|
if (upper->lowest) {
|
|
list_del_init(&upper->lower);
|
|
upper->lowest = 0;
|
|
}
|
|
|
|
list_add_tail(&edge->list[UPPER], &upper->lower);
|
|
continue;
|
|
}
|
|
|
|
if (!upper->checked) {
|
|
/*
|
|
* Still want to blow up for developers since this is a
|
|
* logic bug.
|
|
*/
|
|
ASSERT(0);
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
if (cowonly != upper->cowonly) {
|
|
ASSERT(0);
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
if (!cowonly) {
|
|
rb_node = tree_insert(&cache->rb_root, upper->bytenr,
|
|
&upper->rb_node);
|
|
if (rb_node)
|
|
backref_tree_panic(rb_node, -EEXIST,
|
|
upper->bytenr);
|
|
}
|
|
|
|
list_add_tail(&edge->list[UPPER], &upper->lower);
|
|
|
|
list_for_each_entry(edge, &upper->upper, list[LOWER])
|
|
list_add_tail(&edge->list[UPPER], &list);
|
|
}
|
|
/*
|
|
* process useless backref nodes. backref nodes for tree leaves
|
|
* are deleted from the cache. backref nodes for upper level
|
|
* tree blocks are left in the cache to avoid unnecessary backref
|
|
* lookup.
|
|
*/
|
|
while (!list_empty(&useless)) {
|
|
upper = list_entry(useless.next, struct backref_node, list);
|
|
list_del_init(&upper->list);
|
|
ASSERT(list_empty(&upper->upper));
|
|
if (upper == node)
|
|
node = NULL;
|
|
if (upper->lowest) {
|
|
list_del_init(&upper->lower);
|
|
upper->lowest = 0;
|
|
}
|
|
while (!list_empty(&upper->lower)) {
|
|
edge = list_entry(upper->lower.next,
|
|
struct backref_edge, list[UPPER]);
|
|
list_del(&edge->list[UPPER]);
|
|
list_del(&edge->list[LOWER]);
|
|
lower = edge->node[LOWER];
|
|
free_backref_edge(cache, edge);
|
|
|
|
if (list_empty(&lower->upper))
|
|
list_add(&lower->list, &useless);
|
|
}
|
|
__mark_block_processed(rc, upper);
|
|
if (upper->level > 0) {
|
|
list_add(&upper->list, &cache->detached);
|
|
upper->detached = 1;
|
|
} else {
|
|
rb_erase(&upper->rb_node, &cache->rb_root);
|
|
free_backref_node(cache, upper);
|
|
}
|
|
}
|
|
out:
|
|
btrfs_free_path(path1);
|
|
btrfs_free_path(path2);
|
|
if (err) {
|
|
while (!list_empty(&useless)) {
|
|
lower = list_entry(useless.next,
|
|
struct backref_node, list);
|
|
list_del_init(&lower->list);
|
|
}
|
|
while (!list_empty(&list)) {
|
|
edge = list_first_entry(&list, struct backref_edge,
|
|
list[UPPER]);
|
|
list_del(&edge->list[UPPER]);
|
|
list_del(&edge->list[LOWER]);
|
|
lower = edge->node[LOWER];
|
|
upper = edge->node[UPPER];
|
|
free_backref_edge(cache, edge);
|
|
|
|
/*
|
|
* Lower is no longer linked to any upper backref nodes
|
|
* and isn't in the cache, we can free it ourselves.
|
|
*/
|
|
if (list_empty(&lower->upper) &&
|
|
RB_EMPTY_NODE(&lower->rb_node))
|
|
list_add(&lower->list, &useless);
|
|
|
|
if (!RB_EMPTY_NODE(&upper->rb_node))
|
|
continue;
|
|
|
|
/* Add this guy's upper edges to the list to proces */
|
|
list_for_each_entry(edge, &upper->upper, list[LOWER])
|
|
list_add_tail(&edge->list[UPPER], &list);
|
|
if (list_empty(&upper->upper))
|
|
list_add(&upper->list, &useless);
|
|
}
|
|
|
|
while (!list_empty(&useless)) {
|
|
lower = list_entry(useless.next,
|
|
struct backref_node, list);
|
|
list_del_init(&lower->list);
|
|
free_backref_node(cache, lower);
|
|
}
|
|
return ERR_PTR(err);
|
|
}
|
|
ASSERT(!node || !node->detached);
|
|
return node;
|
|
}
|
|
|
|
/*
|
|
* helper to add backref node for the newly created snapshot.
|
|
* the backref node is created by cloning backref node that
|
|
* corresponds to root of source tree
|
|
*/
|
|
static int clone_backref_node(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct btrfs_root *src,
|
|
struct btrfs_root *dest)
|
|
{
|
|
struct btrfs_root *reloc_root = src->reloc_root;
|
|
struct backref_cache *cache = &rc->backref_cache;
|
|
struct backref_node *node = NULL;
|
|
struct backref_node *new_node;
|
|
struct backref_edge *edge;
|
|
struct backref_edge *new_edge;
|
|
struct rb_node *rb_node;
|
|
|
|
if (cache->last_trans > 0)
|
|
update_backref_cache(trans, cache);
|
|
|
|
rb_node = tree_search(&cache->rb_root, src->commit_root->start);
|
|
if (rb_node) {
|
|
node = rb_entry(rb_node, struct backref_node, rb_node);
|
|
if (node->detached)
|
|
node = NULL;
|
|
else
|
|
BUG_ON(node->new_bytenr != reloc_root->node->start);
|
|
}
|
|
|
|
if (!node) {
|
|
rb_node = tree_search(&cache->rb_root,
|
|
reloc_root->commit_root->start);
|
|
if (rb_node) {
|
|
node = rb_entry(rb_node, struct backref_node,
|
|
rb_node);
|
|
BUG_ON(node->detached);
|
|
}
|
|
}
|
|
|
|
if (!node)
|
|
return 0;
|
|
|
|
new_node = alloc_backref_node(cache);
|
|
if (!new_node)
|
|
return -ENOMEM;
|
|
|
|
new_node->bytenr = dest->node->start;
|
|
new_node->level = node->level;
|
|
new_node->lowest = node->lowest;
|
|
new_node->checked = 1;
|
|
new_node->root = dest;
|
|
|
|
if (!node->lowest) {
|
|
list_for_each_entry(edge, &node->lower, list[UPPER]) {
|
|
new_edge = alloc_backref_edge(cache);
|
|
if (!new_edge)
|
|
goto fail;
|
|
|
|
new_edge->node[UPPER] = new_node;
|
|
new_edge->node[LOWER] = edge->node[LOWER];
|
|
list_add_tail(&new_edge->list[UPPER],
|
|
&new_node->lower);
|
|
}
|
|
} else {
|
|
list_add_tail(&new_node->lower, &cache->leaves);
|
|
}
|
|
|
|
rb_node = tree_insert(&cache->rb_root, new_node->bytenr,
|
|
&new_node->rb_node);
|
|
if (rb_node)
|
|
backref_tree_panic(rb_node, -EEXIST, new_node->bytenr);
|
|
|
|
if (!new_node->lowest) {
|
|
list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) {
|
|
list_add_tail(&new_edge->list[LOWER],
|
|
&new_edge->node[LOWER]->upper);
|
|
}
|
|
}
|
|
return 0;
|
|
fail:
|
|
while (!list_empty(&new_node->lower)) {
|
|
new_edge = list_entry(new_node->lower.next,
|
|
struct backref_edge, list[UPPER]);
|
|
list_del(&new_edge->list[UPPER]);
|
|
free_backref_edge(cache, new_edge);
|
|
}
|
|
free_backref_node(cache, new_node);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* helper to add 'address of tree root -> reloc tree' mapping
|
|
*/
|
|
static int __must_check __add_reloc_root(struct btrfs_root *root)
|
|
{
|
|
struct rb_node *rb_node;
|
|
struct mapping_node *node;
|
|
struct reloc_control *rc = root->fs_info->reloc_ctl;
|
|
|
|
node = kmalloc(sizeof(*node), GFP_NOFS);
|
|
if (!node)
|
|
return -ENOMEM;
|
|
|
|
node->bytenr = root->node->start;
|
|
node->data = root;
|
|
|
|
spin_lock(&rc->reloc_root_tree.lock);
|
|
rb_node = tree_insert(&rc->reloc_root_tree.rb_root,
|
|
node->bytenr, &node->rb_node);
|
|
spin_unlock(&rc->reloc_root_tree.lock);
|
|
if (rb_node) {
|
|
btrfs_panic(root->fs_info, -EEXIST, "Duplicate root found "
|
|
"for start=%llu while inserting into relocation "
|
|
"tree", node->bytenr);
|
|
kfree(node);
|
|
return -EEXIST;
|
|
}
|
|
|
|
list_add_tail(&root->root_list, &rc->reloc_roots);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* helper to delete the 'address of tree root -> reloc tree'
|
|
* mapping
|
|
*/
|
|
static void __del_reloc_root(struct btrfs_root *root)
|
|
{
|
|
struct rb_node *rb_node;
|
|
struct mapping_node *node = NULL;
|
|
struct reloc_control *rc = root->fs_info->reloc_ctl;
|
|
|
|
spin_lock(&rc->reloc_root_tree.lock);
|
|
rb_node = tree_search(&rc->reloc_root_tree.rb_root,
|
|
root->node->start);
|
|
if (rb_node) {
|
|
node = rb_entry(rb_node, struct mapping_node, rb_node);
|
|
rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root);
|
|
}
|
|
spin_unlock(&rc->reloc_root_tree.lock);
|
|
|
|
if (!node)
|
|
return;
|
|
BUG_ON((struct btrfs_root *)node->data != root);
|
|
|
|
spin_lock(&root->fs_info->trans_lock);
|
|
list_del_init(&root->root_list);
|
|
spin_unlock(&root->fs_info->trans_lock);
|
|
kfree(node);
|
|
}
|
|
|
|
/*
|
|
* helper to update the 'address of tree root -> reloc tree'
|
|
* mapping
|
|
*/
|
|
static int __update_reloc_root(struct btrfs_root *root, u64 new_bytenr)
|
|
{
|
|
struct rb_node *rb_node;
|
|
struct mapping_node *node = NULL;
|
|
struct reloc_control *rc = root->fs_info->reloc_ctl;
|
|
|
|
spin_lock(&rc->reloc_root_tree.lock);
|
|
rb_node = tree_search(&rc->reloc_root_tree.rb_root,
|
|
root->node->start);
|
|
if (rb_node) {
|
|
node = rb_entry(rb_node, struct mapping_node, rb_node);
|
|
rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root);
|
|
}
|
|
spin_unlock(&rc->reloc_root_tree.lock);
|
|
|
|
if (!node)
|
|
return 0;
|
|
BUG_ON((struct btrfs_root *)node->data != root);
|
|
|
|
spin_lock(&rc->reloc_root_tree.lock);
|
|
node->bytenr = new_bytenr;
|
|
rb_node = tree_insert(&rc->reloc_root_tree.rb_root,
|
|
node->bytenr, &node->rb_node);
|
|
spin_unlock(&rc->reloc_root_tree.lock);
|
|
if (rb_node)
|
|
backref_tree_panic(rb_node, -EEXIST, node->bytenr);
|
|
return 0;
|
|
}
|
|
|
|
static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root, u64 objectid)
|
|
{
|
|
struct btrfs_root *reloc_root;
|
|
struct extent_buffer *eb;
|
|
struct btrfs_root_item *root_item;
|
|
struct btrfs_key root_key;
|
|
u64 last_snap = 0;
|
|
int ret;
|
|
|
|
root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
|
|
BUG_ON(!root_item);
|
|
|
|
root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
|
|
root_key.type = BTRFS_ROOT_ITEM_KEY;
|
|
root_key.offset = objectid;
|
|
|
|
if (root->root_key.objectid == objectid) {
|
|
/* called by btrfs_init_reloc_root */
|
|
ret = btrfs_copy_root(trans, root, root->commit_root, &eb,
|
|
BTRFS_TREE_RELOC_OBJECTID);
|
|
BUG_ON(ret);
|
|
|
|
last_snap = btrfs_root_last_snapshot(&root->root_item);
|
|
btrfs_set_root_last_snapshot(&root->root_item,
|
|
trans->transid - 1);
|
|
} else {
|
|
/*
|
|
* called by btrfs_reloc_post_snapshot_hook.
|
|
* the source tree is a reloc tree, all tree blocks
|
|
* modified after it was created have RELOC flag
|
|
* set in their headers. so it's OK to not update
|
|
* the 'last_snapshot'.
|
|
*/
|
|
ret = btrfs_copy_root(trans, root, root->node, &eb,
|
|
BTRFS_TREE_RELOC_OBJECTID);
|
|
BUG_ON(ret);
|
|
}
|
|
|
|
memcpy(root_item, &root->root_item, sizeof(*root_item));
|
|
btrfs_set_root_bytenr(root_item, eb->start);
|
|
btrfs_set_root_level(root_item, btrfs_header_level(eb));
|
|
btrfs_set_root_generation(root_item, trans->transid);
|
|
|
|
if (root->root_key.objectid == objectid) {
|
|
btrfs_set_root_refs(root_item, 0);
|
|
memset(&root_item->drop_progress, 0,
|
|
sizeof(struct btrfs_disk_key));
|
|
root_item->drop_level = 0;
|
|
/*
|
|
* abuse rtransid, it is safe because it is impossible to
|
|
* receive data into a relocation tree.
|
|
*/
|
|
btrfs_set_root_rtransid(root_item, last_snap);
|
|
btrfs_set_root_otransid(root_item, trans->transid);
|
|
}
|
|
|
|
btrfs_tree_unlock(eb);
|
|
free_extent_buffer(eb);
|
|
|
|
ret = btrfs_insert_root(trans, root->fs_info->tree_root,
|
|
&root_key, root_item);
|
|
BUG_ON(ret);
|
|
kfree(root_item);
|
|
|
|
reloc_root = btrfs_read_fs_root(root->fs_info->tree_root, &root_key);
|
|
BUG_ON(IS_ERR(reloc_root));
|
|
reloc_root->last_trans = trans->transid;
|
|
return reloc_root;
|
|
}
|
|
|
|
/*
|
|
* create reloc tree for a given fs tree. reloc tree is just a
|
|
* snapshot of the fs tree with special root objectid.
|
|
*/
|
|
int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root)
|
|
{
|
|
struct btrfs_root *reloc_root;
|
|
struct reloc_control *rc = root->fs_info->reloc_ctl;
|
|
struct btrfs_block_rsv *rsv;
|
|
int clear_rsv = 0;
|
|
int ret;
|
|
|
|
if (root->reloc_root) {
|
|
reloc_root = root->reloc_root;
|
|
reloc_root->last_trans = trans->transid;
|
|
return 0;
|
|
}
|
|
|
|
if (!rc || !rc->create_reloc_tree ||
|
|
root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
|
|
return 0;
|
|
|
|
if (!trans->reloc_reserved) {
|
|
rsv = trans->block_rsv;
|
|
trans->block_rsv = rc->block_rsv;
|
|
clear_rsv = 1;
|
|
}
|
|
reloc_root = create_reloc_root(trans, root, root->root_key.objectid);
|
|
if (clear_rsv)
|
|
trans->block_rsv = rsv;
|
|
|
|
ret = __add_reloc_root(reloc_root);
|
|
BUG_ON(ret < 0);
|
|
root->reloc_root = reloc_root;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* update root item of reloc tree
|
|
*/
|
|
int btrfs_update_reloc_root(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root)
|
|
{
|
|
struct btrfs_root *reloc_root;
|
|
struct btrfs_root_item *root_item;
|
|
int ret;
|
|
|
|
if (!root->reloc_root)
|
|
goto out;
|
|
|
|
reloc_root = root->reloc_root;
|
|
root_item = &reloc_root->root_item;
|
|
|
|
if (root->fs_info->reloc_ctl->merge_reloc_tree &&
|
|
btrfs_root_refs(root_item) == 0) {
|
|
root->reloc_root = NULL;
|
|
__del_reloc_root(reloc_root);
|
|
}
|
|
|
|
if (reloc_root->commit_root != reloc_root->node) {
|
|
btrfs_set_root_node(root_item, reloc_root->node);
|
|
free_extent_buffer(reloc_root->commit_root);
|
|
reloc_root->commit_root = btrfs_root_node(reloc_root);
|
|
}
|
|
|
|
ret = btrfs_update_root(trans, root->fs_info->tree_root,
|
|
&reloc_root->root_key, root_item);
|
|
BUG_ON(ret);
|
|
|
|
out:
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* helper to find first cached inode with inode number >= objectid
|
|
* in a subvolume
|
|
*/
|
|
static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid)
|
|
{
|
|
struct rb_node *node;
|
|
struct rb_node *prev;
|
|
struct btrfs_inode *entry;
|
|
struct inode *inode;
|
|
|
|
spin_lock(&root->inode_lock);
|
|
again:
|
|
node = root->inode_tree.rb_node;
|
|
prev = NULL;
|
|
while (node) {
|
|
prev = node;
|
|
entry = rb_entry(node, struct btrfs_inode, rb_node);
|
|
|
|
if (objectid < btrfs_ino(&entry->vfs_inode))
|
|
node = node->rb_left;
|
|
else if (objectid > btrfs_ino(&entry->vfs_inode))
|
|
node = node->rb_right;
|
|
else
|
|
break;
|
|
}
|
|
if (!node) {
|
|
while (prev) {
|
|
entry = rb_entry(prev, struct btrfs_inode, rb_node);
|
|
if (objectid <= btrfs_ino(&entry->vfs_inode)) {
|
|
node = prev;
|
|
break;
|
|
}
|
|
prev = rb_next(prev);
|
|
}
|
|
}
|
|
while (node) {
|
|
entry = rb_entry(node, struct btrfs_inode, rb_node);
|
|
inode = igrab(&entry->vfs_inode);
|
|
if (inode) {
|
|
spin_unlock(&root->inode_lock);
|
|
return inode;
|
|
}
|
|
|
|
objectid = btrfs_ino(&entry->vfs_inode) + 1;
|
|
if (cond_resched_lock(&root->inode_lock))
|
|
goto again;
|
|
|
|
node = rb_next(node);
|
|
}
|
|
spin_unlock(&root->inode_lock);
|
|
return NULL;
|
|
}
|
|
|
|
static int in_block_group(u64 bytenr,
|
|
struct btrfs_block_group_cache *block_group)
|
|
{
|
|
if (bytenr >= block_group->key.objectid &&
|
|
bytenr < block_group->key.objectid + block_group->key.offset)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* get new location of data
|
|
*/
|
|
static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr,
|
|
u64 bytenr, u64 num_bytes)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
|
|
struct btrfs_path *path;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct extent_buffer *leaf;
|
|
int ret;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
|
|
bytenr -= BTRFS_I(reloc_inode)->index_cnt;
|
|
ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(reloc_inode),
|
|
bytenr, 0);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret > 0) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
leaf = path->nodes[0];
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
|
|
BUG_ON(btrfs_file_extent_offset(leaf, fi) ||
|
|
btrfs_file_extent_compression(leaf, fi) ||
|
|
btrfs_file_extent_encryption(leaf, fi) ||
|
|
btrfs_file_extent_other_encoding(leaf, fi));
|
|
|
|
if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
*new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
|
|
ret = 0;
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* update file extent items in the tree leaf to point to
|
|
* the new locations.
|
|
*/
|
|
static noinline_for_stack
|
|
int replace_file_extents(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct btrfs_root *root,
|
|
struct extent_buffer *leaf)
|
|
{
|
|
struct btrfs_key key;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct inode *inode = NULL;
|
|
u64 parent;
|
|
u64 bytenr;
|
|
u64 new_bytenr = 0;
|
|
u64 num_bytes;
|
|
u64 end;
|
|
u32 nritems;
|
|
u32 i;
|
|
int ret = 0;
|
|
int first = 1;
|
|
int dirty = 0;
|
|
|
|
if (rc->stage != UPDATE_DATA_PTRS)
|
|
return 0;
|
|
|
|
/* reloc trees always use full backref */
|
|
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
|
|
parent = leaf->start;
|
|
else
|
|
parent = 0;
|
|
|
|
nritems = btrfs_header_nritems(leaf);
|
|
for (i = 0; i < nritems; i++) {
|
|
cond_resched();
|
|
btrfs_item_key_to_cpu(leaf, &key, i);
|
|
if (key.type != BTRFS_EXTENT_DATA_KEY)
|
|
continue;
|
|
fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
|
|
if (btrfs_file_extent_type(leaf, fi) ==
|
|
BTRFS_FILE_EXTENT_INLINE)
|
|
continue;
|
|
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
|
|
num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
|
|
if (bytenr == 0)
|
|
continue;
|
|
if (!in_block_group(bytenr, rc->block_group))
|
|
continue;
|
|
|
|
/*
|
|
* if we are modifying block in fs tree, wait for readpage
|
|
* to complete and drop the extent cache
|
|
*/
|
|
if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
|
|
if (first) {
|
|
inode = find_next_inode(root, key.objectid);
|
|
first = 0;
|
|
} else if (inode && btrfs_ino(inode) < key.objectid) {
|
|
btrfs_add_delayed_iput(inode);
|
|
inode = find_next_inode(root, key.objectid);
|
|
}
|
|
if (inode && btrfs_ino(inode) == key.objectid) {
|
|
end = key.offset +
|
|
btrfs_file_extent_num_bytes(leaf, fi);
|
|
WARN_ON(!IS_ALIGNED(key.offset,
|
|
root->sectorsize));
|
|
WARN_ON(!IS_ALIGNED(end, root->sectorsize));
|
|
end--;
|
|
ret = try_lock_extent(&BTRFS_I(inode)->io_tree,
|
|
key.offset, end);
|
|
if (!ret)
|
|
continue;
|
|
|
|
btrfs_drop_extent_cache(inode, key.offset, end,
|
|
1);
|
|
unlock_extent(&BTRFS_I(inode)->io_tree,
|
|
key.offset, end);
|
|
}
|
|
}
|
|
|
|
ret = get_new_location(rc->data_inode, &new_bytenr,
|
|
bytenr, num_bytes);
|
|
if (ret) {
|
|
/*
|
|
* Don't have to abort since we've not changed anything
|
|
* in the file extent yet.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr);
|
|
dirty = 1;
|
|
|
|
key.offset -= btrfs_file_extent_offset(leaf, fi);
|
|
ret = btrfs_inc_extent_ref(trans, root, new_bytenr,
|
|
num_bytes, parent,
|
|
btrfs_header_owner(leaf),
|
|
key.objectid, key.offset, 1);
|
|
if (ret) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
break;
|
|
}
|
|
|
|
ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
|
|
parent, btrfs_header_owner(leaf),
|
|
key.objectid, key.offset, 1);
|
|
if (ret) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
break;
|
|
}
|
|
}
|
|
if (dirty)
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
if (inode)
|
|
btrfs_add_delayed_iput(inode);
|
|
return ret;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
int memcmp_node_keys(struct extent_buffer *eb, int slot,
|
|
struct btrfs_path *path, int level)
|
|
{
|
|
struct btrfs_disk_key key1;
|
|
struct btrfs_disk_key key2;
|
|
btrfs_node_key(eb, &key1, slot);
|
|
btrfs_node_key(path->nodes[level], &key2, path->slots[level]);
|
|
return memcmp(&key1, &key2, sizeof(key1));
|
|
}
|
|
|
|
/*
|
|
* try to replace tree blocks in fs tree with the new blocks
|
|
* in reloc tree. tree blocks haven't been modified since the
|
|
* reloc tree was create can be replaced.
|
|
*
|
|
* if a block was replaced, level of the block + 1 is returned.
|
|
* if no block got replaced, 0 is returned. if there are other
|
|
* errors, a negative error number is returned.
|
|
*/
|
|
static noinline_for_stack
|
|
int replace_path(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *dest, struct btrfs_root *src,
|
|
struct btrfs_path *path, struct btrfs_key *next_key,
|
|
int lowest_level, int max_level)
|
|
{
|
|
struct extent_buffer *eb;
|
|
struct extent_buffer *parent;
|
|
struct btrfs_key key;
|
|
u64 old_bytenr;
|
|
u64 new_bytenr;
|
|
u64 old_ptr_gen;
|
|
u64 new_ptr_gen;
|
|
u64 last_snapshot;
|
|
u32 blocksize;
|
|
int cow = 0;
|
|
int level;
|
|
int ret;
|
|
int slot;
|
|
|
|
BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
|
|
BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID);
|
|
|
|
last_snapshot = btrfs_root_last_snapshot(&src->root_item);
|
|
again:
|
|
slot = path->slots[lowest_level];
|
|
btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot);
|
|
|
|
eb = btrfs_lock_root_node(dest);
|
|
btrfs_set_lock_blocking(eb);
|
|
level = btrfs_header_level(eb);
|
|
|
|
if (level < lowest_level) {
|
|
btrfs_tree_unlock(eb);
|
|
free_extent_buffer(eb);
|
|
return 0;
|
|
}
|
|
|
|
if (cow) {
|
|
ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb);
|
|
BUG_ON(ret);
|
|
}
|
|
btrfs_set_lock_blocking(eb);
|
|
|
|
if (next_key) {
|
|
next_key->objectid = (u64)-1;
|
|
next_key->type = (u8)-1;
|
|
next_key->offset = (u64)-1;
|
|
}
|
|
|
|
parent = eb;
|
|
while (1) {
|
|
level = btrfs_header_level(parent);
|
|
BUG_ON(level < lowest_level);
|
|
|
|
ret = btrfs_bin_search(parent, &key, level, &slot);
|
|
if (ret && slot > 0)
|
|
slot--;
|
|
|
|
if (next_key && slot + 1 < btrfs_header_nritems(parent))
|
|
btrfs_node_key_to_cpu(parent, next_key, slot + 1);
|
|
|
|
old_bytenr = btrfs_node_blockptr(parent, slot);
|
|
blocksize = dest->nodesize;
|
|
old_ptr_gen = btrfs_node_ptr_generation(parent, slot);
|
|
|
|
if (level <= max_level) {
|
|
eb = path->nodes[level];
|
|
new_bytenr = btrfs_node_blockptr(eb,
|
|
path->slots[level]);
|
|
new_ptr_gen = btrfs_node_ptr_generation(eb,
|
|
path->slots[level]);
|
|
} else {
|
|
new_bytenr = 0;
|
|
new_ptr_gen = 0;
|
|
}
|
|
|
|
if (WARN_ON(new_bytenr > 0 && new_bytenr == old_bytenr)) {
|
|
ret = level;
|
|
break;
|
|
}
|
|
|
|
if (new_bytenr == 0 || old_ptr_gen > last_snapshot ||
|
|
memcmp_node_keys(parent, slot, path, level)) {
|
|
if (level <= lowest_level) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
|
|
eb = read_tree_block(dest, old_bytenr, old_ptr_gen);
|
|
if (IS_ERR(eb)) {
|
|
ret = PTR_ERR(eb);
|
|
} else if (!extent_buffer_uptodate(eb)) {
|
|
ret = -EIO;
|
|
free_extent_buffer(eb);
|
|
break;
|
|
}
|
|
btrfs_tree_lock(eb);
|
|
if (cow) {
|
|
ret = btrfs_cow_block(trans, dest, eb, parent,
|
|
slot, &eb);
|
|
BUG_ON(ret);
|
|
}
|
|
btrfs_set_lock_blocking(eb);
|
|
|
|
btrfs_tree_unlock(parent);
|
|
free_extent_buffer(parent);
|
|
|
|
parent = eb;
|
|
continue;
|
|
}
|
|
|
|
if (!cow) {
|
|
btrfs_tree_unlock(parent);
|
|
free_extent_buffer(parent);
|
|
cow = 1;
|
|
goto again;
|
|
}
|
|
|
|
btrfs_node_key_to_cpu(path->nodes[level], &key,
|
|
path->slots[level]);
|
|
btrfs_release_path(path);
|
|
|
|
path->lowest_level = level;
|
|
ret = btrfs_search_slot(trans, src, &key, path, 0, 1);
|
|
path->lowest_level = 0;
|
|
BUG_ON(ret);
|
|
|
|
/*
|
|
* swap blocks in fs tree and reloc tree.
|
|
*/
|
|
btrfs_set_node_blockptr(parent, slot, new_bytenr);
|
|
btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen);
|
|
btrfs_mark_buffer_dirty(parent);
|
|
|
|
btrfs_set_node_blockptr(path->nodes[level],
|
|
path->slots[level], old_bytenr);
|
|
btrfs_set_node_ptr_generation(path->nodes[level],
|
|
path->slots[level], old_ptr_gen);
|
|
btrfs_mark_buffer_dirty(path->nodes[level]);
|
|
|
|
ret = btrfs_inc_extent_ref(trans, src, old_bytenr, blocksize,
|
|
path->nodes[level]->start,
|
|
src->root_key.objectid, level - 1, 0,
|
|
1);
|
|
BUG_ON(ret);
|
|
ret = btrfs_inc_extent_ref(trans, dest, new_bytenr, blocksize,
|
|
0, dest->root_key.objectid, level - 1,
|
|
0, 1);
|
|
BUG_ON(ret);
|
|
|
|
ret = btrfs_free_extent(trans, src, new_bytenr, blocksize,
|
|
path->nodes[level]->start,
|
|
src->root_key.objectid, level - 1, 0,
|
|
1);
|
|
BUG_ON(ret);
|
|
|
|
ret = btrfs_free_extent(trans, dest, old_bytenr, blocksize,
|
|
0, dest->root_key.objectid, level - 1,
|
|
0, 1);
|
|
BUG_ON(ret);
|
|
|
|
btrfs_unlock_up_safe(path, 0);
|
|
|
|
ret = level;
|
|
break;
|
|
}
|
|
btrfs_tree_unlock(parent);
|
|
free_extent_buffer(parent);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* helper to find next relocated block in reloc tree
|
|
*/
|
|
static noinline_for_stack
|
|
int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path,
|
|
int *level)
|
|
{
|
|
struct extent_buffer *eb;
|
|
int i;
|
|
u64 last_snapshot;
|
|
u32 nritems;
|
|
|
|
last_snapshot = btrfs_root_last_snapshot(&root->root_item);
|
|
|
|
for (i = 0; i < *level; i++) {
|
|
free_extent_buffer(path->nodes[i]);
|
|
path->nodes[i] = NULL;
|
|
}
|
|
|
|
for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
|
|
eb = path->nodes[i];
|
|
nritems = btrfs_header_nritems(eb);
|
|
while (path->slots[i] + 1 < nritems) {
|
|
path->slots[i]++;
|
|
if (btrfs_node_ptr_generation(eb, path->slots[i]) <=
|
|
last_snapshot)
|
|
continue;
|
|
|
|
*level = i;
|
|
return 0;
|
|
}
|
|
free_extent_buffer(path->nodes[i]);
|
|
path->nodes[i] = NULL;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* walk down reloc tree to find relocated block of lowest level
|
|
*/
|
|
static noinline_for_stack
|
|
int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path,
|
|
int *level)
|
|
{
|
|
struct extent_buffer *eb = NULL;
|
|
int i;
|
|
u64 bytenr;
|
|
u64 ptr_gen = 0;
|
|
u64 last_snapshot;
|
|
u32 nritems;
|
|
|
|
last_snapshot = btrfs_root_last_snapshot(&root->root_item);
|
|
|
|
for (i = *level; i > 0; i--) {
|
|
eb = path->nodes[i];
|
|
nritems = btrfs_header_nritems(eb);
|
|
while (path->slots[i] < nritems) {
|
|
ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]);
|
|
if (ptr_gen > last_snapshot)
|
|
break;
|
|
path->slots[i]++;
|
|
}
|
|
if (path->slots[i] >= nritems) {
|
|
if (i == *level)
|
|
break;
|
|
*level = i + 1;
|
|
return 0;
|
|
}
|
|
if (i == 1) {
|
|
*level = i;
|
|
return 0;
|
|
}
|
|
|
|
bytenr = btrfs_node_blockptr(eb, path->slots[i]);
|
|
eb = read_tree_block(root, bytenr, ptr_gen);
|
|
if (IS_ERR(eb)) {
|
|
return PTR_ERR(eb);
|
|
} else if (!extent_buffer_uptodate(eb)) {
|
|
free_extent_buffer(eb);
|
|
return -EIO;
|
|
}
|
|
BUG_ON(btrfs_header_level(eb) != i - 1);
|
|
path->nodes[i - 1] = eb;
|
|
path->slots[i - 1] = 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* invalidate extent cache for file extents whose key in range of
|
|
* [min_key, max_key)
|
|
*/
|
|
static int invalidate_extent_cache(struct btrfs_root *root,
|
|
struct btrfs_key *min_key,
|
|
struct btrfs_key *max_key)
|
|
{
|
|
struct inode *inode = NULL;
|
|
u64 objectid;
|
|
u64 start, end;
|
|
u64 ino;
|
|
|
|
objectid = min_key->objectid;
|
|
while (1) {
|
|
cond_resched();
|
|
iput(inode);
|
|
|
|
if (objectid > max_key->objectid)
|
|
break;
|
|
|
|
inode = find_next_inode(root, objectid);
|
|
if (!inode)
|
|
break;
|
|
ino = btrfs_ino(inode);
|
|
|
|
if (ino > max_key->objectid) {
|
|
iput(inode);
|
|
break;
|
|
}
|
|
|
|
objectid = ino + 1;
|
|
if (!S_ISREG(inode->i_mode))
|
|
continue;
|
|
|
|
if (unlikely(min_key->objectid == ino)) {
|
|
if (min_key->type > BTRFS_EXTENT_DATA_KEY)
|
|
continue;
|
|
if (min_key->type < BTRFS_EXTENT_DATA_KEY)
|
|
start = 0;
|
|
else {
|
|
start = min_key->offset;
|
|
WARN_ON(!IS_ALIGNED(start, root->sectorsize));
|
|
}
|
|
} else {
|
|
start = 0;
|
|
}
|
|
|
|
if (unlikely(max_key->objectid == ino)) {
|
|
if (max_key->type < BTRFS_EXTENT_DATA_KEY)
|
|
continue;
|
|
if (max_key->type > BTRFS_EXTENT_DATA_KEY) {
|
|
end = (u64)-1;
|
|
} else {
|
|
if (max_key->offset == 0)
|
|
continue;
|
|
end = max_key->offset;
|
|
WARN_ON(!IS_ALIGNED(end, root->sectorsize));
|
|
end--;
|
|
}
|
|
} else {
|
|
end = (u64)-1;
|
|
}
|
|
|
|
/* the lock_extent waits for readpage to complete */
|
|
lock_extent(&BTRFS_I(inode)->io_tree, start, end);
|
|
btrfs_drop_extent_cache(inode, start, end, 1);
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int find_next_key(struct btrfs_path *path, int level,
|
|
struct btrfs_key *key)
|
|
|
|
{
|
|
while (level < BTRFS_MAX_LEVEL) {
|
|
if (!path->nodes[level])
|
|
break;
|
|
if (path->slots[level] + 1 <
|
|
btrfs_header_nritems(path->nodes[level])) {
|
|
btrfs_node_key_to_cpu(path->nodes[level], key,
|
|
path->slots[level] + 1);
|
|
return 0;
|
|
}
|
|
level++;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* merge the relocated tree blocks in reloc tree with corresponding
|
|
* fs tree.
|
|
*/
|
|
static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
|
|
struct btrfs_root *root)
|
|
{
|
|
LIST_HEAD(inode_list);
|
|
struct btrfs_key key;
|
|
struct btrfs_key next_key;
|
|
struct btrfs_trans_handle *trans = NULL;
|
|
struct btrfs_root *reloc_root;
|
|
struct btrfs_root_item *root_item;
|
|
struct btrfs_path *path;
|
|
struct extent_buffer *leaf;
|
|
int level;
|
|
int max_level;
|
|
int replaced = 0;
|
|
int ret;
|
|
int err = 0;
|
|
u32 min_reserved;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
path->reada = 1;
|
|
|
|
reloc_root = root->reloc_root;
|
|
root_item = &reloc_root->root_item;
|
|
|
|
if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
|
|
level = btrfs_root_level(root_item);
|
|
extent_buffer_get(reloc_root->node);
|
|
path->nodes[level] = reloc_root->node;
|
|
path->slots[level] = 0;
|
|
} else {
|
|
btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
|
|
|
|
level = root_item->drop_level;
|
|
BUG_ON(level == 0);
|
|
path->lowest_level = level;
|
|
ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0);
|
|
path->lowest_level = 0;
|
|
if (ret < 0) {
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
btrfs_node_key_to_cpu(path->nodes[level], &next_key,
|
|
path->slots[level]);
|
|
WARN_ON(memcmp(&key, &next_key, sizeof(key)));
|
|
|
|
btrfs_unlock_up_safe(path, 0);
|
|
}
|
|
|
|
min_reserved = root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2;
|
|
memset(&next_key, 0, sizeof(next_key));
|
|
|
|
while (1) {
|
|
ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved,
|
|
BTRFS_RESERVE_FLUSH_ALL);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
trans = btrfs_start_transaction(root, 0);
|
|
if (IS_ERR(trans)) {
|
|
err = PTR_ERR(trans);
|
|
trans = NULL;
|
|
goto out;
|
|
}
|
|
trans->block_rsv = rc->block_rsv;
|
|
|
|
replaced = 0;
|
|
max_level = level;
|
|
|
|
ret = walk_down_reloc_tree(reloc_root, path, &level);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
if (ret > 0)
|
|
break;
|
|
|
|
if (!find_next_key(path, level, &key) &&
|
|
btrfs_comp_cpu_keys(&next_key, &key) >= 0) {
|
|
ret = 0;
|
|
} else {
|
|
ret = replace_path(trans, root, reloc_root, path,
|
|
&next_key, level, max_level);
|
|
}
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
|
|
if (ret > 0) {
|
|
level = ret;
|
|
btrfs_node_key_to_cpu(path->nodes[level], &key,
|
|
path->slots[level]);
|
|
replaced = 1;
|
|
}
|
|
|
|
ret = walk_up_reloc_tree(reloc_root, path, &level);
|
|
if (ret > 0)
|
|
break;
|
|
|
|
BUG_ON(level == 0);
|
|
/*
|
|
* save the merging progress in the drop_progress.
|
|
* this is OK since root refs == 1 in this case.
|
|
*/
|
|
btrfs_node_key(path->nodes[level], &root_item->drop_progress,
|
|
path->slots[level]);
|
|
root_item->drop_level = level;
|
|
|
|
btrfs_end_transaction_throttle(trans, root);
|
|
trans = NULL;
|
|
|
|
btrfs_btree_balance_dirty(root);
|
|
|
|
if (replaced && rc->stage == UPDATE_DATA_PTRS)
|
|
invalidate_extent_cache(root, &key, &next_key);
|
|
}
|
|
|
|
/*
|
|
* handle the case only one block in the fs tree need to be
|
|
* relocated and the block is tree root.
|
|
*/
|
|
leaf = btrfs_lock_root_node(root);
|
|
ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf);
|
|
btrfs_tree_unlock(leaf);
|
|
free_extent_buffer(leaf);
|
|
if (ret < 0)
|
|
err = ret;
|
|
out:
|
|
btrfs_free_path(path);
|
|
|
|
if (err == 0) {
|
|
memset(&root_item->drop_progress, 0,
|
|
sizeof(root_item->drop_progress));
|
|
root_item->drop_level = 0;
|
|
btrfs_set_root_refs(root_item, 0);
|
|
btrfs_update_reloc_root(trans, root);
|
|
}
|
|
|
|
if (trans)
|
|
btrfs_end_transaction_throttle(trans, root);
|
|
|
|
btrfs_btree_balance_dirty(root);
|
|
|
|
if (replaced && rc->stage == UPDATE_DATA_PTRS)
|
|
invalidate_extent_cache(root, &key, &next_key);
|
|
|
|
return err;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
int prepare_to_merge(struct reloc_control *rc, int err)
|
|
{
|
|
struct btrfs_root *root = rc->extent_root;
|
|
struct btrfs_root *reloc_root;
|
|
struct btrfs_trans_handle *trans;
|
|
LIST_HEAD(reloc_roots);
|
|
u64 num_bytes = 0;
|
|
int ret;
|
|
|
|
mutex_lock(&root->fs_info->reloc_mutex);
|
|
rc->merging_rsv_size += root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2;
|
|
rc->merging_rsv_size += rc->nodes_relocated * 2;
|
|
mutex_unlock(&root->fs_info->reloc_mutex);
|
|
|
|
again:
|
|
if (!err) {
|
|
num_bytes = rc->merging_rsv_size;
|
|
ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes,
|
|
BTRFS_RESERVE_FLUSH_ALL);
|
|
if (ret)
|
|
err = ret;
|
|
}
|
|
|
|
trans = btrfs_join_transaction(rc->extent_root);
|
|
if (IS_ERR(trans)) {
|
|
if (!err)
|
|
btrfs_block_rsv_release(rc->extent_root,
|
|
rc->block_rsv, num_bytes);
|
|
return PTR_ERR(trans);
|
|
}
|
|
|
|
if (!err) {
|
|
if (num_bytes != rc->merging_rsv_size) {
|
|
btrfs_end_transaction(trans, rc->extent_root);
|
|
btrfs_block_rsv_release(rc->extent_root,
|
|
rc->block_rsv, num_bytes);
|
|
goto again;
|
|
}
|
|
}
|
|
|
|
rc->merge_reloc_tree = 1;
|
|
|
|
while (!list_empty(&rc->reloc_roots)) {
|
|
reloc_root = list_entry(rc->reloc_roots.next,
|
|
struct btrfs_root, root_list);
|
|
list_del_init(&reloc_root->root_list);
|
|
|
|
root = read_fs_root(reloc_root->fs_info,
|
|
reloc_root->root_key.offset);
|
|
BUG_ON(IS_ERR(root));
|
|
BUG_ON(root->reloc_root != reloc_root);
|
|
|
|
/*
|
|
* set reference count to 1, so btrfs_recover_relocation
|
|
* knows it should resumes merging
|
|
*/
|
|
if (!err)
|
|
btrfs_set_root_refs(&reloc_root->root_item, 1);
|
|
btrfs_update_reloc_root(trans, root);
|
|
|
|
list_add(&reloc_root->root_list, &reloc_roots);
|
|
}
|
|
|
|
list_splice(&reloc_roots, &rc->reloc_roots);
|
|
|
|
if (!err)
|
|
btrfs_commit_transaction(trans, rc->extent_root);
|
|
else
|
|
btrfs_end_transaction(trans, rc->extent_root);
|
|
return err;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
void free_reloc_roots(struct list_head *list)
|
|
{
|
|
struct btrfs_root *reloc_root;
|
|
|
|
while (!list_empty(list)) {
|
|
reloc_root = list_entry(list->next, struct btrfs_root,
|
|
root_list);
|
|
__del_reloc_root(reloc_root);
|
|
}
|
|
}
|
|
|
|
static noinline_for_stack
|
|
void merge_reloc_roots(struct reloc_control *rc)
|
|
{
|
|
struct btrfs_root *root;
|
|
struct btrfs_root *reloc_root;
|
|
u64 last_snap;
|
|
u64 otransid;
|
|
u64 objectid;
|
|
LIST_HEAD(reloc_roots);
|
|
int found = 0;
|
|
int ret = 0;
|
|
again:
|
|
root = rc->extent_root;
|
|
|
|
/*
|
|
* this serializes us with btrfs_record_root_in_transaction,
|
|
* we have to make sure nobody is in the middle of
|
|
* adding their roots to the list while we are
|
|
* doing this splice
|
|
*/
|
|
mutex_lock(&root->fs_info->reloc_mutex);
|
|
list_splice_init(&rc->reloc_roots, &reloc_roots);
|
|
mutex_unlock(&root->fs_info->reloc_mutex);
|
|
|
|
while (!list_empty(&reloc_roots)) {
|
|
found = 1;
|
|
reloc_root = list_entry(reloc_roots.next,
|
|
struct btrfs_root, root_list);
|
|
|
|
if (btrfs_root_refs(&reloc_root->root_item) > 0) {
|
|
root = read_fs_root(reloc_root->fs_info,
|
|
reloc_root->root_key.offset);
|
|
BUG_ON(IS_ERR(root));
|
|
BUG_ON(root->reloc_root != reloc_root);
|
|
|
|
ret = merge_reloc_root(rc, root);
|
|
if (ret) {
|
|
if (list_empty(&reloc_root->root_list))
|
|
list_add_tail(&reloc_root->root_list,
|
|
&reloc_roots);
|
|
goto out;
|
|
}
|
|
} else {
|
|
list_del_init(&reloc_root->root_list);
|
|
}
|
|
|
|
/*
|
|
* we keep the old last snapshod transid in rtranid when we
|
|
* created the relocation tree.
|
|
*/
|
|
last_snap = btrfs_root_rtransid(&reloc_root->root_item);
|
|
otransid = btrfs_root_otransid(&reloc_root->root_item);
|
|
objectid = reloc_root->root_key.offset;
|
|
|
|
ret = btrfs_drop_snapshot(reloc_root, rc->block_rsv, 0, 1);
|
|
if (ret < 0) {
|
|
if (list_empty(&reloc_root->root_list))
|
|
list_add_tail(&reloc_root->root_list,
|
|
&reloc_roots);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (found) {
|
|
found = 0;
|
|
goto again;
|
|
}
|
|
out:
|
|
if (ret) {
|
|
btrfs_std_error(root->fs_info, ret);
|
|
if (!list_empty(&reloc_roots))
|
|
free_reloc_roots(&reloc_roots);
|
|
|
|
/* new reloc root may be added */
|
|
mutex_lock(&root->fs_info->reloc_mutex);
|
|
list_splice_init(&rc->reloc_roots, &reloc_roots);
|
|
mutex_unlock(&root->fs_info->reloc_mutex);
|
|
if (!list_empty(&reloc_roots))
|
|
free_reloc_roots(&reloc_roots);
|
|
}
|
|
|
|
BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root));
|
|
}
|
|
|
|
static void free_block_list(struct rb_root *blocks)
|
|
{
|
|
struct tree_block *block;
|
|
struct rb_node *rb_node;
|
|
while ((rb_node = rb_first(blocks))) {
|
|
block = rb_entry(rb_node, struct tree_block, rb_node);
|
|
rb_erase(rb_node, blocks);
|
|
kfree(block);
|
|
}
|
|
}
|
|
|
|
static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *reloc_root)
|
|
{
|
|
struct btrfs_root *root;
|
|
|
|
if (reloc_root->last_trans == trans->transid)
|
|
return 0;
|
|
|
|
root = read_fs_root(reloc_root->fs_info, reloc_root->root_key.offset);
|
|
BUG_ON(IS_ERR(root));
|
|
BUG_ON(root->reloc_root != reloc_root);
|
|
|
|
return btrfs_record_root_in_trans(trans, root);
|
|
}
|
|
|
|
static noinline_for_stack
|
|
struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct backref_node *node,
|
|
struct backref_edge *edges[])
|
|
{
|
|
struct backref_node *next;
|
|
struct btrfs_root *root;
|
|
int index = 0;
|
|
|
|
next = node;
|
|
while (1) {
|
|
cond_resched();
|
|
next = walk_up_backref(next, edges, &index);
|
|
root = next->root;
|
|
BUG_ON(!root);
|
|
BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS, &root->state));
|
|
|
|
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
|
|
record_reloc_root_in_trans(trans, root);
|
|
break;
|
|
}
|
|
|
|
btrfs_record_root_in_trans(trans, root);
|
|
root = root->reloc_root;
|
|
|
|
if (next->new_bytenr != root->node->start) {
|
|
BUG_ON(next->new_bytenr);
|
|
BUG_ON(!list_empty(&next->list));
|
|
next->new_bytenr = root->node->start;
|
|
next->root = root;
|
|
list_add_tail(&next->list,
|
|
&rc->backref_cache.changed);
|
|
__mark_block_processed(rc, next);
|
|
break;
|
|
}
|
|
|
|
WARN_ON(1);
|
|
root = NULL;
|
|
next = walk_down_backref(edges, &index);
|
|
if (!next || next->level <= node->level)
|
|
break;
|
|
}
|
|
if (!root)
|
|
return NULL;
|
|
|
|
next = node;
|
|
/* setup backref node path for btrfs_reloc_cow_block */
|
|
while (1) {
|
|
rc->backref_cache.path[next->level] = next;
|
|
if (--index < 0)
|
|
break;
|
|
next = edges[index]->node[UPPER];
|
|
}
|
|
return root;
|
|
}
|
|
|
|
/*
|
|
* select a tree root for relocation. return NULL if the block
|
|
* is reference counted. we should use do_relocation() in this
|
|
* case. return a tree root pointer if the block isn't reference
|
|
* counted. return -ENOENT if the block is root of reloc tree.
|
|
*/
|
|
static noinline_for_stack
|
|
struct btrfs_root *select_one_root(struct backref_node *node)
|
|
{
|
|
struct backref_node *next;
|
|
struct btrfs_root *root;
|
|
struct btrfs_root *fs_root = NULL;
|
|
struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
|
|
int index = 0;
|
|
|
|
next = node;
|
|
while (1) {
|
|
cond_resched();
|
|
next = walk_up_backref(next, edges, &index);
|
|
root = next->root;
|
|
BUG_ON(!root);
|
|
|
|
/* no other choice for non-references counted tree */
|
|
if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
|
|
return root;
|
|
|
|
if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID)
|
|
fs_root = root;
|
|
|
|
if (next != node)
|
|
return NULL;
|
|
|
|
next = walk_down_backref(edges, &index);
|
|
if (!next || next->level <= node->level)
|
|
break;
|
|
}
|
|
|
|
if (!fs_root)
|
|
return ERR_PTR(-ENOENT);
|
|
return fs_root;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
u64 calcu_metadata_size(struct reloc_control *rc,
|
|
struct backref_node *node, int reserve)
|
|
{
|
|
struct backref_node *next = node;
|
|
struct backref_edge *edge;
|
|
struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
|
|
u64 num_bytes = 0;
|
|
int index = 0;
|
|
|
|
BUG_ON(reserve && node->processed);
|
|
|
|
while (next) {
|
|
cond_resched();
|
|
while (1) {
|
|
if (next->processed && (reserve || next != node))
|
|
break;
|
|
|
|
num_bytes += rc->extent_root->nodesize;
|
|
|
|
if (list_empty(&next->upper))
|
|
break;
|
|
|
|
edge = list_entry(next->upper.next,
|
|
struct backref_edge, list[LOWER]);
|
|
edges[index++] = edge;
|
|
next = edge->node[UPPER];
|
|
}
|
|
next = walk_down_backref(edges, &index);
|
|
}
|
|
return num_bytes;
|
|
}
|
|
|
|
static int reserve_metadata_space(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct backref_node *node)
|
|
{
|
|
struct btrfs_root *root = rc->extent_root;
|
|
u64 num_bytes;
|
|
int ret;
|
|
u64 tmp;
|
|
|
|
num_bytes = calcu_metadata_size(rc, node, 1) * 2;
|
|
|
|
trans->block_rsv = rc->block_rsv;
|
|
rc->reserved_bytes += num_bytes;
|
|
ret = btrfs_block_rsv_refill(root, rc->block_rsv, num_bytes,
|
|
BTRFS_RESERVE_FLUSH_ALL);
|
|
if (ret) {
|
|
if (ret == -EAGAIN) {
|
|
tmp = rc->extent_root->nodesize *
|
|
RELOCATION_RESERVED_NODES;
|
|
while (tmp <= rc->reserved_bytes)
|
|
tmp <<= 1;
|
|
/*
|
|
* only one thread can access block_rsv at this point,
|
|
* so we don't need hold lock to protect block_rsv.
|
|
* we expand more reservation size here to allow enough
|
|
* space for relocation and we will return eailer in
|
|
* enospc case.
|
|
*/
|
|
rc->block_rsv->size = tmp + rc->extent_root->nodesize *
|
|
RELOCATION_RESERVED_NODES;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* relocate a block tree, and then update pointers in upper level
|
|
* blocks that reference the block to point to the new location.
|
|
*
|
|
* if called by link_to_upper, the block has already been relocated.
|
|
* in that case this function just updates pointers.
|
|
*/
|
|
static int do_relocation(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct backref_node *node,
|
|
struct btrfs_key *key,
|
|
struct btrfs_path *path, int lowest)
|
|
{
|
|
struct backref_node *upper;
|
|
struct backref_edge *edge;
|
|
struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
|
|
struct btrfs_root *root;
|
|
struct extent_buffer *eb;
|
|
u32 blocksize;
|
|
u64 bytenr;
|
|
u64 generation;
|
|
int slot;
|
|
int ret;
|
|
int err = 0;
|
|
|
|
BUG_ON(lowest && node->eb);
|
|
|
|
path->lowest_level = node->level + 1;
|
|
rc->backref_cache.path[node->level] = node;
|
|
list_for_each_entry(edge, &node->upper, list[LOWER]) {
|
|
cond_resched();
|
|
|
|
upper = edge->node[UPPER];
|
|
root = select_reloc_root(trans, rc, upper, edges);
|
|
BUG_ON(!root);
|
|
|
|
if (upper->eb && !upper->locked) {
|
|
if (!lowest) {
|
|
ret = btrfs_bin_search(upper->eb, key,
|
|
upper->level, &slot);
|
|
BUG_ON(ret);
|
|
bytenr = btrfs_node_blockptr(upper->eb, slot);
|
|
if (node->eb->start == bytenr)
|
|
goto next;
|
|
}
|
|
drop_node_buffer(upper);
|
|
}
|
|
|
|
if (!upper->eb) {
|
|
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
BUG_ON(ret > 0);
|
|
|
|
if (!upper->eb) {
|
|
upper->eb = path->nodes[upper->level];
|
|
path->nodes[upper->level] = NULL;
|
|
} else {
|
|
BUG_ON(upper->eb != path->nodes[upper->level]);
|
|
}
|
|
|
|
upper->locked = 1;
|
|
path->locks[upper->level] = 0;
|
|
|
|
slot = path->slots[upper->level];
|
|
btrfs_release_path(path);
|
|
} else {
|
|
ret = btrfs_bin_search(upper->eb, key, upper->level,
|
|
&slot);
|
|
BUG_ON(ret);
|
|
}
|
|
|
|
bytenr = btrfs_node_blockptr(upper->eb, slot);
|
|
if (lowest) {
|
|
BUG_ON(bytenr != node->bytenr);
|
|
} else {
|
|
if (node->eb->start == bytenr)
|
|
goto next;
|
|
}
|
|
|
|
blocksize = root->nodesize;
|
|
generation = btrfs_node_ptr_generation(upper->eb, slot);
|
|
eb = read_tree_block(root, bytenr, generation);
|
|
if (IS_ERR(eb)) {
|
|
err = PTR_ERR(eb);
|
|
goto next;
|
|
} else if (!extent_buffer_uptodate(eb)) {
|
|
free_extent_buffer(eb);
|
|
err = -EIO;
|
|
goto next;
|
|
}
|
|
btrfs_tree_lock(eb);
|
|
btrfs_set_lock_blocking(eb);
|
|
|
|
if (!node->eb) {
|
|
ret = btrfs_cow_block(trans, root, eb, upper->eb,
|
|
slot, &eb);
|
|
btrfs_tree_unlock(eb);
|
|
free_extent_buffer(eb);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto next;
|
|
}
|
|
BUG_ON(node->eb != eb);
|
|
} else {
|
|
btrfs_set_node_blockptr(upper->eb, slot,
|
|
node->eb->start);
|
|
btrfs_set_node_ptr_generation(upper->eb, slot,
|
|
trans->transid);
|
|
btrfs_mark_buffer_dirty(upper->eb);
|
|
|
|
ret = btrfs_inc_extent_ref(trans, root,
|
|
node->eb->start, blocksize,
|
|
upper->eb->start,
|
|
btrfs_header_owner(upper->eb),
|
|
node->level, 0, 1);
|
|
BUG_ON(ret);
|
|
|
|
ret = btrfs_drop_subtree(trans, root, eb, upper->eb);
|
|
BUG_ON(ret);
|
|
}
|
|
next:
|
|
if (!upper->pending)
|
|
drop_node_buffer(upper);
|
|
else
|
|
unlock_node_buffer(upper);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
if (!err && node->pending) {
|
|
drop_node_buffer(node);
|
|
list_move_tail(&node->list, &rc->backref_cache.changed);
|
|
node->pending = 0;
|
|
}
|
|
|
|
path->lowest_level = 0;
|
|
BUG_ON(err == -ENOSPC);
|
|
return err;
|
|
}
|
|
|
|
static int link_to_upper(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct backref_node *node,
|
|
struct btrfs_path *path)
|
|
{
|
|
struct btrfs_key key;
|
|
|
|
btrfs_node_key_to_cpu(node->eb, &key, 0);
|
|
return do_relocation(trans, rc, node, &key, path, 0);
|
|
}
|
|
|
|
static int finish_pending_nodes(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct btrfs_path *path, int err)
|
|
{
|
|
LIST_HEAD(list);
|
|
struct backref_cache *cache = &rc->backref_cache;
|
|
struct backref_node *node;
|
|
int level;
|
|
int ret;
|
|
|
|
for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
|
|
while (!list_empty(&cache->pending[level])) {
|
|
node = list_entry(cache->pending[level].next,
|
|
struct backref_node, list);
|
|
list_move_tail(&node->list, &list);
|
|
BUG_ON(!node->pending);
|
|
|
|
if (!err) {
|
|
ret = link_to_upper(trans, rc, node, path);
|
|
if (ret < 0)
|
|
err = ret;
|
|
}
|
|
}
|
|
list_splice_init(&list, &cache->pending[level]);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static void mark_block_processed(struct reloc_control *rc,
|
|
u64 bytenr, u32 blocksize)
|
|
{
|
|
set_extent_bits(&rc->processed_blocks, bytenr, bytenr + blocksize - 1,
|
|
EXTENT_DIRTY, GFP_NOFS);
|
|
}
|
|
|
|
static void __mark_block_processed(struct reloc_control *rc,
|
|
struct backref_node *node)
|
|
{
|
|
u32 blocksize;
|
|
if (node->level == 0 ||
|
|
in_block_group(node->bytenr, rc->block_group)) {
|
|
blocksize = rc->extent_root->nodesize;
|
|
mark_block_processed(rc, node->bytenr, blocksize);
|
|
}
|
|
node->processed = 1;
|
|
}
|
|
|
|
/*
|
|
* mark a block and all blocks directly/indirectly reference the block
|
|
* as processed.
|
|
*/
|
|
static void update_processed_blocks(struct reloc_control *rc,
|
|
struct backref_node *node)
|
|
{
|
|
struct backref_node *next = node;
|
|
struct backref_edge *edge;
|
|
struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
|
|
int index = 0;
|
|
|
|
while (next) {
|
|
cond_resched();
|
|
while (1) {
|
|
if (next->processed)
|
|
break;
|
|
|
|
__mark_block_processed(rc, next);
|
|
|
|
if (list_empty(&next->upper))
|
|
break;
|
|
|
|
edge = list_entry(next->upper.next,
|
|
struct backref_edge, list[LOWER]);
|
|
edges[index++] = edge;
|
|
next = edge->node[UPPER];
|
|
}
|
|
next = walk_down_backref(edges, &index);
|
|
}
|
|
}
|
|
|
|
static int tree_block_processed(u64 bytenr, struct reloc_control *rc)
|
|
{
|
|
u32 blocksize = rc->extent_root->nodesize;
|
|
|
|
if (test_range_bit(&rc->processed_blocks, bytenr,
|
|
bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int get_tree_block_key(struct reloc_control *rc,
|
|
struct tree_block *block)
|
|
{
|
|
struct extent_buffer *eb;
|
|
|
|
BUG_ON(block->key_ready);
|
|
eb = read_tree_block(rc->extent_root, block->bytenr,
|
|
block->key.offset);
|
|
if (IS_ERR(eb)) {
|
|
return PTR_ERR(eb);
|
|
} else if (!extent_buffer_uptodate(eb)) {
|
|
free_extent_buffer(eb);
|
|
return -EIO;
|
|
}
|
|
WARN_ON(btrfs_header_level(eb) != block->level);
|
|
if (block->level == 0)
|
|
btrfs_item_key_to_cpu(eb, &block->key, 0);
|
|
else
|
|
btrfs_node_key_to_cpu(eb, &block->key, 0);
|
|
free_extent_buffer(eb);
|
|
block->key_ready = 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* helper function to relocate a tree block
|
|
*/
|
|
static int relocate_tree_block(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc,
|
|
struct backref_node *node,
|
|
struct btrfs_key *key,
|
|
struct btrfs_path *path)
|
|
{
|
|
struct btrfs_root *root;
|
|
int ret = 0;
|
|
|
|
if (!node)
|
|
return 0;
|
|
|
|
BUG_ON(node->processed);
|
|
root = select_one_root(node);
|
|
if (root == ERR_PTR(-ENOENT)) {
|
|
update_processed_blocks(rc, node);
|
|
goto out;
|
|
}
|
|
|
|
if (!root || test_bit(BTRFS_ROOT_REF_COWS, &root->state)) {
|
|
ret = reserve_metadata_space(trans, rc, node);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
if (root) {
|
|
if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) {
|
|
BUG_ON(node->new_bytenr);
|
|
BUG_ON(!list_empty(&node->list));
|
|
btrfs_record_root_in_trans(trans, root);
|
|
root = root->reloc_root;
|
|
node->new_bytenr = root->node->start;
|
|
node->root = root;
|
|
list_add_tail(&node->list, &rc->backref_cache.changed);
|
|
} else {
|
|
path->lowest_level = node->level;
|
|
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
|
|
btrfs_release_path(path);
|
|
if (ret > 0)
|
|
ret = 0;
|
|
}
|
|
if (!ret)
|
|
update_processed_blocks(rc, node);
|
|
} else {
|
|
ret = do_relocation(trans, rc, node, key, path, 1);
|
|
}
|
|
out:
|
|
if (ret || node->level == 0 || node->cowonly)
|
|
remove_backref_node(&rc->backref_cache, node);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* relocate a list of blocks
|
|
*/
|
|
static noinline_for_stack
|
|
int relocate_tree_blocks(struct btrfs_trans_handle *trans,
|
|
struct reloc_control *rc, struct rb_root *blocks)
|
|
{
|
|
struct backref_node *node;
|
|
struct btrfs_path *path;
|
|
struct tree_block *block;
|
|
struct rb_node *rb_node;
|
|
int ret;
|
|
int err = 0;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
err = -ENOMEM;
|
|
goto out_free_blocks;
|
|
}
|
|
|
|
rb_node = rb_first(blocks);
|
|
while (rb_node) {
|
|
block = rb_entry(rb_node, struct tree_block, rb_node);
|
|
if (!block->key_ready)
|
|
readahead_tree_block(rc->extent_root, block->bytenr);
|
|
rb_node = rb_next(rb_node);
|
|
}
|
|
|
|
rb_node = rb_first(blocks);
|
|
while (rb_node) {
|
|
block = rb_entry(rb_node, struct tree_block, rb_node);
|
|
if (!block->key_ready) {
|
|
err = get_tree_block_key(rc, block);
|
|
if (err)
|
|
goto out_free_path;
|
|
}
|
|
rb_node = rb_next(rb_node);
|
|
}
|
|
|
|
rb_node = rb_first(blocks);
|
|
while (rb_node) {
|
|
block = rb_entry(rb_node, struct tree_block, rb_node);
|
|
|
|
node = build_backref_tree(rc, &block->key,
|
|
block->level, block->bytenr);
|
|
if (IS_ERR(node)) {
|
|
err = PTR_ERR(node);
|
|
goto out;
|
|
}
|
|
|
|
ret = relocate_tree_block(trans, rc, node, &block->key,
|
|
path);
|
|
if (ret < 0) {
|
|
if (ret != -EAGAIN || rb_node == rb_first(blocks))
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
rb_node = rb_next(rb_node);
|
|
}
|
|
out:
|
|
err = finish_pending_nodes(trans, rc, path, err);
|
|
|
|
out_free_path:
|
|
btrfs_free_path(path);
|
|
out_free_blocks:
|
|
free_block_list(blocks);
|
|
return err;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
int prealloc_file_extent_cluster(struct inode *inode,
|
|
struct file_extent_cluster *cluster)
|
|
{
|
|
u64 alloc_hint = 0;
|
|
u64 start;
|
|
u64 end;
|
|
u64 offset = BTRFS_I(inode)->index_cnt;
|
|
u64 num_bytes;
|
|
int nr = 0;
|
|
int ret = 0;
|
|
|
|
BUG_ON(cluster->start != cluster->boundary[0]);
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
ret = btrfs_check_data_free_space(inode, cluster->end +
|
|
1 - cluster->start, 0);
|
|
if (ret)
|
|
goto out;
|
|
|
|
while (nr < cluster->nr) {
|
|
start = cluster->boundary[nr] - offset;
|
|
if (nr + 1 < cluster->nr)
|
|
end = cluster->boundary[nr + 1] - 1 - offset;
|
|
else
|
|
end = cluster->end - offset;
|
|
|
|
lock_extent(&BTRFS_I(inode)->io_tree, start, end);
|
|
num_bytes = end + 1 - start;
|
|
ret = btrfs_prealloc_file_range(inode, 0, start,
|
|
num_bytes, num_bytes,
|
|
end + 1, &alloc_hint);
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
|
|
if (ret)
|
|
break;
|
|
nr++;
|
|
}
|
|
btrfs_free_reserved_data_space(inode, cluster->end +
|
|
1 - cluster->start);
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
int setup_extent_mapping(struct inode *inode, u64 start, u64 end,
|
|
u64 block_start)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
|
|
struct extent_map *em;
|
|
int ret = 0;
|
|
|
|
em = alloc_extent_map();
|
|
if (!em)
|
|
return -ENOMEM;
|
|
|
|
em->start = start;
|
|
em->len = end + 1 - start;
|
|
em->block_len = em->len;
|
|
em->block_start = block_start;
|
|
em->bdev = root->fs_info->fs_devices->latest_bdev;
|
|
set_bit(EXTENT_FLAG_PINNED, &em->flags);
|
|
|
|
lock_extent(&BTRFS_I(inode)->io_tree, start, end);
|
|
while (1) {
|
|
write_lock(&em_tree->lock);
|
|
ret = add_extent_mapping(em_tree, em, 0);
|
|
write_unlock(&em_tree->lock);
|
|
if (ret != -EEXIST) {
|
|
free_extent_map(em);
|
|
break;
|
|
}
|
|
btrfs_drop_extent_cache(inode, start, end, 0);
|
|
}
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
|
|
return ret;
|
|
}
|
|
|
|
static int relocate_file_extent_cluster(struct inode *inode,
|
|
struct file_extent_cluster *cluster)
|
|
{
|
|
u64 page_start;
|
|
u64 page_end;
|
|
u64 offset = BTRFS_I(inode)->index_cnt;
|
|
unsigned long index;
|
|
unsigned long last_index;
|
|
struct page *page;
|
|
struct file_ra_state *ra;
|
|
gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
|
|
int nr = 0;
|
|
int ret = 0;
|
|
|
|
if (!cluster->nr)
|
|
return 0;
|
|
|
|
ra = kzalloc(sizeof(*ra), GFP_NOFS);
|
|
if (!ra)
|
|
return -ENOMEM;
|
|
|
|
ret = prealloc_file_extent_cluster(inode, cluster);
|
|
if (ret)
|
|
goto out;
|
|
|
|
file_ra_state_init(ra, inode->i_mapping);
|
|
|
|
ret = setup_extent_mapping(inode, cluster->start - offset,
|
|
cluster->end - offset, cluster->start);
|
|
if (ret)
|
|
goto out;
|
|
|
|
index = (cluster->start - offset) >> PAGE_CACHE_SHIFT;
|
|
last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT;
|
|
while (index <= last_index) {
|
|
ret = btrfs_delalloc_reserve_metadata(inode, PAGE_CACHE_SIZE);
|
|
if (ret)
|
|
goto out;
|
|
|
|
page = find_lock_page(inode->i_mapping, index);
|
|
if (!page) {
|
|
page_cache_sync_readahead(inode->i_mapping,
|
|
ra, NULL, index,
|
|
last_index + 1 - index);
|
|
page = find_or_create_page(inode->i_mapping, index,
|
|
mask);
|
|
if (!page) {
|
|
btrfs_delalloc_release_metadata(inode,
|
|
PAGE_CACHE_SIZE);
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (PageReadahead(page)) {
|
|
page_cache_async_readahead(inode->i_mapping,
|
|
ra, NULL, page, index,
|
|
last_index + 1 - index);
|
|
}
|
|
|
|
if (!PageUptodate(page)) {
|
|
btrfs_readpage(NULL, page);
|
|
lock_page(page);
|
|
if (!PageUptodate(page)) {
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
btrfs_delalloc_release_metadata(inode,
|
|
PAGE_CACHE_SIZE);
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
page_start = page_offset(page);
|
|
page_end = page_start + PAGE_CACHE_SIZE - 1;
|
|
|
|
lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end);
|
|
|
|
set_page_extent_mapped(page);
|
|
|
|
if (nr < cluster->nr &&
|
|
page_start + offset == cluster->boundary[nr]) {
|
|
set_extent_bits(&BTRFS_I(inode)->io_tree,
|
|
page_start, page_end,
|
|
EXTENT_BOUNDARY, GFP_NOFS);
|
|
nr++;
|
|
}
|
|
|
|
btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
|
|
set_page_dirty(page);
|
|
|
|
unlock_extent(&BTRFS_I(inode)->io_tree,
|
|
page_start, page_end);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
|
|
index++;
|
|
balance_dirty_pages_ratelimited(inode->i_mapping);
|
|
btrfs_throttle(BTRFS_I(inode)->root);
|
|
}
|
|
WARN_ON(nr != cluster->nr);
|
|
out:
|
|
kfree(ra);
|
|
return ret;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key,
|
|
struct file_extent_cluster *cluster)
|
|
{
|
|
int ret;
|
|
|
|
if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) {
|
|
ret = relocate_file_extent_cluster(inode, cluster);
|
|
if (ret)
|
|
return ret;
|
|
cluster->nr = 0;
|
|
}
|
|
|
|
if (!cluster->nr)
|
|
cluster->start = extent_key->objectid;
|
|
else
|
|
BUG_ON(cluster->nr >= MAX_EXTENTS);
|
|
cluster->end = extent_key->objectid + extent_key->offset - 1;
|
|
cluster->boundary[cluster->nr] = extent_key->objectid;
|
|
cluster->nr++;
|
|
|
|
if (cluster->nr >= MAX_EXTENTS) {
|
|
ret = relocate_file_extent_cluster(inode, cluster);
|
|
if (ret)
|
|
return ret;
|
|
cluster->nr = 0;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
static int get_ref_objectid_v0(struct reloc_control *rc,
|
|
struct btrfs_path *path,
|
|
struct btrfs_key *extent_key,
|
|
u64 *ref_objectid, int *path_change)
|
|
{
|
|
struct btrfs_key key;
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_extent_ref_v0 *ref0;
|
|
int ret;
|
|
int slot;
|
|
|
|
leaf = path->nodes[0];
|
|
slot = path->slots[0];
|
|
while (1) {
|
|
if (slot >= btrfs_header_nritems(leaf)) {
|
|
ret = btrfs_next_leaf(rc->extent_root, path);
|
|
if (ret < 0)
|
|
return ret;
|
|
BUG_ON(ret > 0);
|
|
leaf = path->nodes[0];
|
|
slot = path->slots[0];
|
|
if (path_change)
|
|
*path_change = 1;
|
|
}
|
|
btrfs_item_key_to_cpu(leaf, &key, slot);
|
|
if (key.objectid != extent_key->objectid)
|
|
return -ENOENT;
|
|
|
|
if (key.type != BTRFS_EXTENT_REF_V0_KEY) {
|
|
slot++;
|
|
continue;
|
|
}
|
|
ref0 = btrfs_item_ptr(leaf, slot,
|
|
struct btrfs_extent_ref_v0);
|
|
*ref_objectid = btrfs_ref_objectid_v0(leaf, ref0);
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* helper to add a tree block to the list.
|
|
* the major work is getting the generation and level of the block
|
|
*/
|
|
static int add_tree_block(struct reloc_control *rc,
|
|
struct btrfs_key *extent_key,
|
|
struct btrfs_path *path,
|
|
struct rb_root *blocks)
|
|
{
|
|
struct extent_buffer *eb;
|
|
struct btrfs_extent_item *ei;
|
|
struct btrfs_tree_block_info *bi;
|
|
struct tree_block *block;
|
|
struct rb_node *rb_node;
|
|
u32 item_size;
|
|
int level = -1;
|
|
u64 generation;
|
|
|
|
eb = path->nodes[0];
|
|
item_size = btrfs_item_size_nr(eb, path->slots[0]);
|
|
|
|
if (extent_key->type == BTRFS_METADATA_ITEM_KEY ||
|
|
item_size >= sizeof(*ei) + sizeof(*bi)) {
|
|
ei = btrfs_item_ptr(eb, path->slots[0],
|
|
struct btrfs_extent_item);
|
|
if (extent_key->type == BTRFS_EXTENT_ITEM_KEY) {
|
|
bi = (struct btrfs_tree_block_info *)(ei + 1);
|
|
level = btrfs_tree_block_level(eb, bi);
|
|
} else {
|
|
level = (int)extent_key->offset;
|
|
}
|
|
generation = btrfs_extent_generation(eb, ei);
|
|
} else {
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
u64 ref_owner;
|
|
int ret;
|
|
|
|
BUG_ON(item_size != sizeof(struct btrfs_extent_item_v0));
|
|
ret = get_ref_objectid_v0(rc, path, extent_key,
|
|
&ref_owner, NULL);
|
|
if (ret < 0)
|
|
return ret;
|
|
BUG_ON(ref_owner >= BTRFS_MAX_LEVEL);
|
|
level = (int)ref_owner;
|
|
/* FIXME: get real generation */
|
|
generation = 0;
|
|
#else
|
|
BUG();
|
|
#endif
|
|
}
|
|
|
|
btrfs_release_path(path);
|
|
|
|
BUG_ON(level == -1);
|
|
|
|
block = kmalloc(sizeof(*block), GFP_NOFS);
|
|
if (!block)
|
|
return -ENOMEM;
|
|
|
|
block->bytenr = extent_key->objectid;
|
|
block->key.objectid = rc->extent_root->nodesize;
|
|
block->key.offset = generation;
|
|
block->level = level;
|
|
block->key_ready = 0;
|
|
|
|
rb_node = tree_insert(blocks, block->bytenr, &block->rb_node);
|
|
if (rb_node)
|
|
backref_tree_panic(rb_node, -EEXIST, block->bytenr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY
|
|
*/
|
|
static int __add_tree_block(struct reloc_control *rc,
|
|
u64 bytenr, u32 blocksize,
|
|
struct rb_root *blocks)
|
|
{
|
|
struct btrfs_path *path;
|
|
struct btrfs_key key;
|
|
int ret;
|
|
bool skinny = btrfs_fs_incompat(rc->extent_root->fs_info,
|
|
SKINNY_METADATA);
|
|
|
|
if (tree_block_processed(bytenr, rc))
|
|
return 0;
|
|
|
|
if (tree_search(blocks, bytenr))
|
|
return 0;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
again:
|
|
key.objectid = bytenr;
|
|
if (skinny) {
|
|
key.type = BTRFS_METADATA_ITEM_KEY;
|
|
key.offset = (u64)-1;
|
|
} else {
|
|
key.type = BTRFS_EXTENT_ITEM_KEY;
|
|
key.offset = blocksize;
|
|
}
|
|
|
|
path->search_commit_root = 1;
|
|
path->skip_locking = 1;
|
|
ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0);
|
|
if (ret < 0)
|
|
goto out;
|
|
|
|
if (ret > 0 && skinny) {
|
|
if (path->slots[0]) {
|
|
path->slots[0]--;
|
|
btrfs_item_key_to_cpu(path->nodes[0], &key,
|
|
path->slots[0]);
|
|
if (key.objectid == bytenr &&
|
|
(key.type == BTRFS_METADATA_ITEM_KEY ||
|
|
(key.type == BTRFS_EXTENT_ITEM_KEY &&
|
|
key.offset == blocksize)))
|
|
ret = 0;
|
|
}
|
|
|
|
if (ret) {
|
|
skinny = false;
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
}
|
|
BUG_ON(ret);
|
|
|
|
ret = add_tree_block(rc, &key, path, blocks);
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* helper to check if the block use full backrefs for pointers in it
|
|
*/
|
|
static int block_use_full_backref(struct reloc_control *rc,
|
|
struct extent_buffer *eb)
|
|
{
|
|
u64 flags;
|
|
int ret;
|
|
|
|
if (btrfs_header_flag(eb, BTRFS_HEADER_FLAG_RELOC) ||
|
|
btrfs_header_backref_rev(eb) < BTRFS_MIXED_BACKREF_REV)
|
|
return 1;
|
|
|
|
ret = btrfs_lookup_extent_info(NULL, rc->extent_root,
|
|
eb->start, btrfs_header_level(eb), 1,
|
|
NULL, &flags);
|
|
BUG_ON(ret);
|
|
|
|
if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)
|
|
ret = 1;
|
|
else
|
|
ret = 0;
|
|
return ret;
|
|
}
|
|
|
|
static int delete_block_group_cache(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_block_group_cache *block_group,
|
|
struct inode *inode,
|
|
u64 ino)
|
|
{
|
|
struct btrfs_key key;
|
|
struct btrfs_root *root = fs_info->tree_root;
|
|
struct btrfs_trans_handle *trans;
|
|
int ret = 0;
|
|
|
|
if (inode)
|
|
goto truncate;
|
|
|
|
key.objectid = ino;
|
|
key.type = BTRFS_INODE_ITEM_KEY;
|
|
key.offset = 0;
|
|
|
|
inode = btrfs_iget(fs_info->sb, &key, root, NULL);
|
|
if (IS_ERR(inode) || is_bad_inode(inode)) {
|
|
if (!IS_ERR(inode))
|
|
iput(inode);
|
|
return -ENOENT;
|
|
}
|
|
|
|
truncate:
|
|
ret = btrfs_check_trunc_cache_free_space(root,
|
|
&fs_info->global_block_rsv);
|
|
if (ret)
|
|
goto out;
|
|
|
|
trans = btrfs_join_transaction(root);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
goto out;
|
|
}
|
|
|
|
ret = btrfs_truncate_free_space_cache(root, trans, block_group, inode);
|
|
|
|
btrfs_end_transaction(trans, root);
|
|
btrfs_btree_balance_dirty(root);
|
|
out:
|
|
iput(inode);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY
|
|
* this function scans fs tree to find blocks reference the data extent
|
|
*/
|
|
static int find_data_references(struct reloc_control *rc,
|
|
struct btrfs_key *extent_key,
|
|
struct extent_buffer *leaf,
|
|
struct btrfs_extent_data_ref *ref,
|
|
struct rb_root *blocks)
|
|
{
|
|
struct btrfs_path *path;
|
|
struct tree_block *block;
|
|
struct btrfs_root *root;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct rb_node *rb_node;
|
|
struct btrfs_key key;
|
|
u64 ref_root;
|
|
u64 ref_objectid;
|
|
u64 ref_offset;
|
|
u32 ref_count;
|
|
u32 nritems;
|
|
int err = 0;
|
|
int added = 0;
|
|
int counted;
|
|
int ret;
|
|
|
|
ref_root = btrfs_extent_data_ref_root(leaf, ref);
|
|
ref_objectid = btrfs_extent_data_ref_objectid(leaf, ref);
|
|
ref_offset = btrfs_extent_data_ref_offset(leaf, ref);
|
|
ref_count = btrfs_extent_data_ref_count(leaf, ref);
|
|
|
|
/*
|
|
* This is an extent belonging to the free space cache, lets just delete
|
|
* it and redo the search.
|
|
*/
|
|
if (ref_root == BTRFS_ROOT_TREE_OBJECTID) {
|
|
ret = delete_block_group_cache(rc->extent_root->fs_info,
|
|
rc->block_group,
|
|
NULL, ref_objectid);
|
|
if (ret != -ENOENT)
|
|
return ret;
|
|
ret = 0;
|
|
}
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
path->reada = 1;
|
|
|
|
root = read_fs_root(rc->extent_root->fs_info, ref_root);
|
|
if (IS_ERR(root)) {
|
|
err = PTR_ERR(root);
|
|
goto out;
|
|
}
|
|
|
|
key.objectid = ref_objectid;
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
if (ref_offset > ((u64)-1 << 32))
|
|
key.offset = 0;
|
|
else
|
|
key.offset = ref_offset;
|
|
|
|
path->search_commit_root = 1;
|
|
path->skip_locking = 1;
|
|
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
|
|
leaf = path->nodes[0];
|
|
nritems = btrfs_header_nritems(leaf);
|
|
/*
|
|
* the references in tree blocks that use full backrefs
|
|
* are not counted in
|
|
*/
|
|
if (block_use_full_backref(rc, leaf))
|
|
counted = 0;
|
|
else
|
|
counted = 1;
|
|
rb_node = tree_search(blocks, leaf->start);
|
|
if (rb_node) {
|
|
if (counted)
|
|
added = 1;
|
|
else
|
|
path->slots[0] = nritems;
|
|
}
|
|
|
|
while (ref_count > 0) {
|
|
while (path->slots[0] >= nritems) {
|
|
ret = btrfs_next_leaf(root, path);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
if (WARN_ON(ret > 0))
|
|
goto out;
|
|
|
|
leaf = path->nodes[0];
|
|
nritems = btrfs_header_nritems(leaf);
|
|
added = 0;
|
|
|
|
if (block_use_full_backref(rc, leaf))
|
|
counted = 0;
|
|
else
|
|
counted = 1;
|
|
rb_node = tree_search(blocks, leaf->start);
|
|
if (rb_node) {
|
|
if (counted)
|
|
added = 1;
|
|
else
|
|
path->slots[0] = nritems;
|
|
}
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
if (WARN_ON(key.objectid != ref_objectid ||
|
|
key.type != BTRFS_EXTENT_DATA_KEY))
|
|
break;
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
|
|
if (btrfs_file_extent_type(leaf, fi) ==
|
|
BTRFS_FILE_EXTENT_INLINE)
|
|
goto next;
|
|
|
|
if (btrfs_file_extent_disk_bytenr(leaf, fi) !=
|
|
extent_key->objectid)
|
|
goto next;
|
|
|
|
key.offset -= btrfs_file_extent_offset(leaf, fi);
|
|
if (key.offset != ref_offset)
|
|
goto next;
|
|
|
|
if (counted)
|
|
ref_count--;
|
|
if (added)
|
|
goto next;
|
|
|
|
if (!tree_block_processed(leaf->start, rc)) {
|
|
block = kmalloc(sizeof(*block), GFP_NOFS);
|
|
if (!block) {
|
|
err = -ENOMEM;
|
|
break;
|
|
}
|
|
block->bytenr = leaf->start;
|
|
btrfs_item_key_to_cpu(leaf, &block->key, 0);
|
|
block->level = 0;
|
|
block->key_ready = 1;
|
|
rb_node = tree_insert(blocks, block->bytenr,
|
|
&block->rb_node);
|
|
if (rb_node)
|
|
backref_tree_panic(rb_node, -EEXIST,
|
|
block->bytenr);
|
|
}
|
|
if (counted)
|
|
added = 1;
|
|
else
|
|
path->slots[0] = nritems;
|
|
next:
|
|
path->slots[0]++;
|
|
|
|
}
|
|
out:
|
|
btrfs_free_path(path);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* helper to find all tree blocks that reference a given data extent
|
|
*/
|
|
static noinline_for_stack
|
|
int add_data_references(struct reloc_control *rc,
|
|
struct btrfs_key *extent_key,
|
|
struct btrfs_path *path,
|
|
struct rb_root *blocks)
|
|
{
|
|
struct btrfs_key key;
|
|
struct extent_buffer *eb;
|
|
struct btrfs_extent_data_ref *dref;
|
|
struct btrfs_extent_inline_ref *iref;
|
|
unsigned long ptr;
|
|
unsigned long end;
|
|
u32 blocksize = rc->extent_root->nodesize;
|
|
int ret = 0;
|
|
int err = 0;
|
|
|
|
eb = path->nodes[0];
|
|
ptr = btrfs_item_ptr_offset(eb, path->slots[0]);
|
|
end = ptr + btrfs_item_size_nr(eb, path->slots[0]);
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
if (ptr + sizeof(struct btrfs_extent_item_v0) == end)
|
|
ptr = end;
|
|
else
|
|
#endif
|
|
ptr += sizeof(struct btrfs_extent_item);
|
|
|
|
while (ptr < end) {
|
|
iref = (struct btrfs_extent_inline_ref *)ptr;
|
|
key.type = btrfs_extent_inline_ref_type(eb, iref);
|
|
if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
|
|
key.offset = btrfs_extent_inline_ref_offset(eb, iref);
|
|
ret = __add_tree_block(rc, key.offset, blocksize,
|
|
blocks);
|
|
} else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
|
|
dref = (struct btrfs_extent_data_ref *)(&iref->offset);
|
|
ret = find_data_references(rc, extent_key,
|
|
eb, dref, blocks);
|
|
} else {
|
|
BUG();
|
|
}
|
|
if (ret) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
ptr += btrfs_extent_inline_ref_size(key.type);
|
|
}
|
|
WARN_ON(ptr > end);
|
|
|
|
while (1) {
|
|
cond_resched();
|
|
eb = path->nodes[0];
|
|
if (path->slots[0] >= btrfs_header_nritems(eb)) {
|
|
ret = btrfs_next_leaf(rc->extent_root, path);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
if (ret > 0)
|
|
break;
|
|
eb = path->nodes[0];
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(eb, &key, path->slots[0]);
|
|
if (key.objectid != extent_key->objectid)
|
|
break;
|
|
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
if (key.type == BTRFS_SHARED_DATA_REF_KEY ||
|
|
key.type == BTRFS_EXTENT_REF_V0_KEY) {
|
|
#else
|
|
BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY);
|
|
if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
|
|
#endif
|
|
ret = __add_tree_block(rc, key.offset, blocksize,
|
|
blocks);
|
|
} else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
|
|
dref = btrfs_item_ptr(eb, path->slots[0],
|
|
struct btrfs_extent_data_ref);
|
|
ret = find_data_references(rc, extent_key,
|
|
eb, dref, blocks);
|
|
} else {
|
|
ret = 0;
|
|
}
|
|
if (ret) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
path->slots[0]++;
|
|
}
|
|
out:
|
|
btrfs_release_path(path);
|
|
if (err)
|
|
free_block_list(blocks);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* helper to find next unprocessed extent
|
|
*/
|
|
static noinline_for_stack
|
|
int find_next_extent(struct reloc_control *rc, struct btrfs_path *path,
|
|
struct btrfs_key *extent_key)
|
|
{
|
|
struct btrfs_key key;
|
|
struct extent_buffer *leaf;
|
|
u64 start, end, last;
|
|
int ret;
|
|
|
|
last = rc->block_group->key.objectid + rc->block_group->key.offset;
|
|
while (1) {
|
|
cond_resched();
|
|
if (rc->search_start >= last) {
|
|
ret = 1;
|
|
break;
|
|
}
|
|
|
|
key.objectid = rc->search_start;
|
|
key.type = BTRFS_EXTENT_ITEM_KEY;
|
|
key.offset = 0;
|
|
|
|
path->search_commit_root = 1;
|
|
path->skip_locking = 1;
|
|
ret = btrfs_search_slot(NULL, rc->extent_root, &key, path,
|
|
0, 0);
|
|
if (ret < 0)
|
|
break;
|
|
next:
|
|
leaf = path->nodes[0];
|
|
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
|
|
ret = btrfs_next_leaf(rc->extent_root, path);
|
|
if (ret != 0)
|
|
break;
|
|
leaf = path->nodes[0];
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
if (key.objectid >= last) {
|
|
ret = 1;
|
|
break;
|
|
}
|
|
|
|
if (key.type != BTRFS_EXTENT_ITEM_KEY &&
|
|
key.type != BTRFS_METADATA_ITEM_KEY) {
|
|
path->slots[0]++;
|
|
goto next;
|
|
}
|
|
|
|
if (key.type == BTRFS_EXTENT_ITEM_KEY &&
|
|
key.objectid + key.offset <= rc->search_start) {
|
|
path->slots[0]++;
|
|
goto next;
|
|
}
|
|
|
|
if (key.type == BTRFS_METADATA_ITEM_KEY &&
|
|
key.objectid + rc->extent_root->nodesize <=
|
|
rc->search_start) {
|
|
path->slots[0]++;
|
|
goto next;
|
|
}
|
|
|
|
ret = find_first_extent_bit(&rc->processed_blocks,
|
|
key.objectid, &start, &end,
|
|
EXTENT_DIRTY, NULL);
|
|
|
|
if (ret == 0 && start <= key.objectid) {
|
|
btrfs_release_path(path);
|
|
rc->search_start = end + 1;
|
|
} else {
|
|
if (key.type == BTRFS_EXTENT_ITEM_KEY)
|
|
rc->search_start = key.objectid + key.offset;
|
|
else
|
|
rc->search_start = key.objectid +
|
|
rc->extent_root->nodesize;
|
|
memcpy(extent_key, &key, sizeof(key));
|
|
return 0;
|
|
}
|
|
}
|
|
btrfs_release_path(path);
|
|
return ret;
|
|
}
|
|
|
|
static void set_reloc_control(struct reloc_control *rc)
|
|
{
|
|
struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
|
|
|
|
mutex_lock(&fs_info->reloc_mutex);
|
|
fs_info->reloc_ctl = rc;
|
|
mutex_unlock(&fs_info->reloc_mutex);
|
|
}
|
|
|
|
static void unset_reloc_control(struct reloc_control *rc)
|
|
{
|
|
struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
|
|
|
|
mutex_lock(&fs_info->reloc_mutex);
|
|
fs_info->reloc_ctl = NULL;
|
|
mutex_unlock(&fs_info->reloc_mutex);
|
|
}
|
|
|
|
static int check_extent_flags(u64 flags)
|
|
{
|
|
if ((flags & BTRFS_EXTENT_FLAG_DATA) &&
|
|
(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
|
|
return 1;
|
|
if (!(flags & BTRFS_EXTENT_FLAG_DATA) &&
|
|
!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
|
|
return 1;
|
|
if ((flags & BTRFS_EXTENT_FLAG_DATA) &&
|
|
(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static noinline_for_stack
|
|
int prepare_to_relocate(struct reloc_control *rc)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
|
|
rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root,
|
|
BTRFS_BLOCK_RSV_TEMP);
|
|
if (!rc->block_rsv)
|
|
return -ENOMEM;
|
|
|
|
memset(&rc->cluster, 0, sizeof(rc->cluster));
|
|
rc->search_start = rc->block_group->key.objectid;
|
|
rc->extents_found = 0;
|
|
rc->nodes_relocated = 0;
|
|
rc->merging_rsv_size = 0;
|
|
rc->reserved_bytes = 0;
|
|
rc->block_rsv->size = rc->extent_root->nodesize *
|
|
RELOCATION_RESERVED_NODES;
|
|
|
|
rc->create_reloc_tree = 1;
|
|
set_reloc_control(rc);
|
|
|
|
trans = btrfs_join_transaction(rc->extent_root);
|
|
if (IS_ERR(trans)) {
|
|
unset_reloc_control(rc);
|
|
/*
|
|
* extent tree is not a ref_cow tree and has no reloc_root to
|
|
* cleanup. And callers are responsible to free the above
|
|
* block rsv.
|
|
*/
|
|
return PTR_ERR(trans);
|
|
}
|
|
btrfs_commit_transaction(trans, rc->extent_root);
|
|
return 0;
|
|
}
|
|
|
|
static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
|
|
{
|
|
struct rb_root blocks = RB_ROOT;
|
|
struct btrfs_key key;
|
|
struct btrfs_trans_handle *trans = NULL;
|
|
struct btrfs_path *path;
|
|
struct btrfs_extent_item *ei;
|
|
u64 flags;
|
|
u32 item_size;
|
|
int ret;
|
|
int err = 0;
|
|
int progress = 0;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
path->reada = 1;
|
|
|
|
ret = prepare_to_relocate(rc);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out_free;
|
|
}
|
|
|
|
while (1) {
|
|
rc->reserved_bytes = 0;
|
|
ret = btrfs_block_rsv_refill(rc->extent_root,
|
|
rc->block_rsv, rc->block_rsv->size,
|
|
BTRFS_RESERVE_FLUSH_ALL);
|
|
if (ret) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
progress++;
|
|
trans = btrfs_start_transaction(rc->extent_root, 0);
|
|
if (IS_ERR(trans)) {
|
|
err = PTR_ERR(trans);
|
|
trans = NULL;
|
|
break;
|
|
}
|
|
restart:
|
|
if (update_backref_cache(trans, &rc->backref_cache)) {
|
|
btrfs_end_transaction(trans, rc->extent_root);
|
|
continue;
|
|
}
|
|
|
|
ret = find_next_extent(rc, path, &key);
|
|
if (ret < 0)
|
|
err = ret;
|
|
if (ret != 0)
|
|
break;
|
|
|
|
rc->extents_found++;
|
|
|
|
ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
|
|
struct btrfs_extent_item);
|
|
item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
|
|
if (item_size >= sizeof(*ei)) {
|
|
flags = btrfs_extent_flags(path->nodes[0], ei);
|
|
ret = check_extent_flags(flags);
|
|
BUG_ON(ret);
|
|
|
|
} else {
|
|
#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
|
|
u64 ref_owner;
|
|
int path_change = 0;
|
|
|
|
BUG_ON(item_size !=
|
|
sizeof(struct btrfs_extent_item_v0));
|
|
ret = get_ref_objectid_v0(rc, path, &key, &ref_owner,
|
|
&path_change);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
if (ref_owner < BTRFS_FIRST_FREE_OBJECTID)
|
|
flags = BTRFS_EXTENT_FLAG_TREE_BLOCK;
|
|
else
|
|
flags = BTRFS_EXTENT_FLAG_DATA;
|
|
|
|
if (path_change) {
|
|
btrfs_release_path(path);
|
|
|
|
path->search_commit_root = 1;
|
|
path->skip_locking = 1;
|
|
ret = btrfs_search_slot(NULL, rc->extent_root,
|
|
&key, path, 0, 0);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
BUG_ON(ret > 0);
|
|
}
|
|
#else
|
|
BUG();
|
|
#endif
|
|
}
|
|
|
|
if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
|
|
ret = add_tree_block(rc, &key, path, &blocks);
|
|
} else if (rc->stage == UPDATE_DATA_PTRS &&
|
|
(flags & BTRFS_EXTENT_FLAG_DATA)) {
|
|
ret = add_data_references(rc, &key, path, &blocks);
|
|
} else {
|
|
btrfs_release_path(path);
|
|
ret = 0;
|
|
}
|
|
if (ret < 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
|
|
if (!RB_EMPTY_ROOT(&blocks)) {
|
|
ret = relocate_tree_blocks(trans, rc, &blocks);
|
|
if (ret < 0) {
|
|
/*
|
|
* if we fail to relocate tree blocks, force to update
|
|
* backref cache when committing transaction.
|
|
*/
|
|
rc->backref_cache.last_trans = trans->transid - 1;
|
|
|
|
if (ret != -EAGAIN) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
rc->extents_found--;
|
|
rc->search_start = key.objectid;
|
|
}
|
|
}
|
|
|
|
btrfs_end_transaction_throttle(trans, rc->extent_root);
|
|
btrfs_btree_balance_dirty(rc->extent_root);
|
|
trans = NULL;
|
|
|
|
if (rc->stage == MOVE_DATA_EXTENTS &&
|
|
(flags & BTRFS_EXTENT_FLAG_DATA)) {
|
|
rc->found_file_extent = 1;
|
|
ret = relocate_data_extent(rc->data_inode,
|
|
&key, &rc->cluster);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (trans && progress && err == -ENOSPC) {
|
|
ret = btrfs_force_chunk_alloc(trans, rc->extent_root,
|
|
rc->block_group->flags);
|
|
if (ret == 1) {
|
|
err = 0;
|
|
progress = 0;
|
|
goto restart;
|
|
}
|
|
}
|
|
|
|
btrfs_release_path(path);
|
|
clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY,
|
|
GFP_NOFS);
|
|
|
|
if (trans) {
|
|
btrfs_end_transaction_throttle(trans, rc->extent_root);
|
|
btrfs_btree_balance_dirty(rc->extent_root);
|
|
}
|
|
|
|
if (!err) {
|
|
ret = relocate_file_extent_cluster(rc->data_inode,
|
|
&rc->cluster);
|
|
if (ret < 0)
|
|
err = ret;
|
|
}
|
|
|
|
rc->create_reloc_tree = 0;
|
|
set_reloc_control(rc);
|
|
|
|
backref_cache_cleanup(&rc->backref_cache);
|
|
btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1);
|
|
|
|
err = prepare_to_merge(rc, err);
|
|
|
|
merge_reloc_roots(rc);
|
|
|
|
rc->merge_reloc_tree = 0;
|
|
unset_reloc_control(rc);
|
|
btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1);
|
|
|
|
/* get rid of pinned extents */
|
|
trans = btrfs_join_transaction(rc->extent_root);
|
|
if (IS_ERR(trans))
|
|
err = PTR_ERR(trans);
|
|
else
|
|
btrfs_commit_transaction(trans, rc->extent_root);
|
|
out_free:
|
|
btrfs_free_block_rsv(rc->extent_root, rc->block_rsv);
|
|
btrfs_free_path(path);
|
|
return err;
|
|
}
|
|
|
|
static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root, u64 objectid)
|
|
{
|
|
struct btrfs_path *path;
|
|
struct btrfs_inode_item *item;
|
|
struct extent_buffer *leaf;
|
|
int ret;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
|
|
ret = btrfs_insert_empty_inode(trans, root, path, objectid);
|
|
if (ret)
|
|
goto out;
|
|
|
|
leaf = path->nodes[0];
|
|
item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
|
|
memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
|
|
btrfs_set_inode_generation(leaf, item, 1);
|
|
btrfs_set_inode_size(leaf, item, 0);
|
|
btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
|
|
btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS |
|
|
BTRFS_INODE_PREALLOC);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* helper to create inode for data relocation.
|
|
* the inode is in data relocation tree and its link count is 0
|
|
*/
|
|
static noinline_for_stack
|
|
struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_block_group_cache *group)
|
|
{
|
|
struct inode *inode = NULL;
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_root *root;
|
|
struct btrfs_key key;
|
|
u64 objectid;
|
|
int err = 0;
|
|
|
|
root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID);
|
|
if (IS_ERR(root))
|
|
return ERR_CAST(root);
|
|
|
|
trans = btrfs_start_transaction(root, 6);
|
|
if (IS_ERR(trans))
|
|
return ERR_CAST(trans);
|
|
|
|
err = btrfs_find_free_objectid(root, &objectid);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = __insert_orphan_inode(trans, root, objectid);
|
|
BUG_ON(err);
|
|
|
|
key.objectid = objectid;
|
|
key.type = BTRFS_INODE_ITEM_KEY;
|
|
key.offset = 0;
|
|
inode = btrfs_iget(root->fs_info->sb, &key, root, NULL);
|
|
BUG_ON(IS_ERR(inode) || is_bad_inode(inode));
|
|
BTRFS_I(inode)->index_cnt = group->key.objectid;
|
|
|
|
err = btrfs_orphan_add(trans, inode);
|
|
out:
|
|
btrfs_end_transaction(trans, root);
|
|
btrfs_btree_balance_dirty(root);
|
|
if (err) {
|
|
if (inode)
|
|
iput(inode);
|
|
inode = ERR_PTR(err);
|
|
}
|
|
return inode;
|
|
}
|
|
|
|
static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info)
|
|
{
|
|
struct reloc_control *rc;
|
|
|
|
rc = kzalloc(sizeof(*rc), GFP_NOFS);
|
|
if (!rc)
|
|
return NULL;
|
|
|
|
INIT_LIST_HEAD(&rc->reloc_roots);
|
|
backref_cache_init(&rc->backref_cache);
|
|
mapping_tree_init(&rc->reloc_root_tree);
|
|
extent_io_tree_init(&rc->processed_blocks,
|
|
fs_info->btree_inode->i_mapping);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* function to relocate all extents in a block group.
|
|
*/
|
|
int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
|
|
{
|
|
struct btrfs_fs_info *fs_info = extent_root->fs_info;
|
|
struct reloc_control *rc;
|
|
struct inode *inode;
|
|
struct btrfs_path *path;
|
|
int ret;
|
|
int rw = 0;
|
|
int err = 0;
|
|
|
|
rc = alloc_reloc_control(fs_info);
|
|
if (!rc)
|
|
return -ENOMEM;
|
|
|
|
rc->extent_root = extent_root;
|
|
|
|
rc->block_group = btrfs_lookup_block_group(fs_info, group_start);
|
|
BUG_ON(!rc->block_group);
|
|
|
|
ret = btrfs_inc_block_group_ro(extent_root, rc->block_group);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
rw = 1;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
inode = lookup_free_space_inode(fs_info->tree_root, rc->block_group,
|
|
path);
|
|
btrfs_free_path(path);
|
|
|
|
if (!IS_ERR(inode))
|
|
ret = delete_block_group_cache(fs_info, rc->block_group, inode, 0);
|
|
else
|
|
ret = PTR_ERR(inode);
|
|
|
|
if (ret && ret != -ENOENT) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
|
|
rc->data_inode = create_reloc_inode(fs_info, rc->block_group);
|
|
if (IS_ERR(rc->data_inode)) {
|
|
err = PTR_ERR(rc->data_inode);
|
|
rc->data_inode = NULL;
|
|
goto out;
|
|
}
|
|
|
|
btrfs_info(extent_root->fs_info, "relocating block group %llu flags %llu",
|
|
rc->block_group->key.objectid, rc->block_group->flags);
|
|
|
|
ret = btrfs_start_delalloc_roots(fs_info, 0, -1);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
btrfs_wait_ordered_roots(fs_info, -1);
|
|
|
|
while (1) {
|
|
mutex_lock(&fs_info->cleaner_mutex);
|
|
ret = relocate_block_group(rc);
|
|
mutex_unlock(&fs_info->cleaner_mutex);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
|
|
if (rc->extents_found == 0)
|
|
break;
|
|
|
|
btrfs_info(extent_root->fs_info, "found %llu extents",
|
|
rc->extents_found);
|
|
|
|
if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) {
|
|
ret = btrfs_wait_ordered_range(rc->data_inode, 0,
|
|
(u64)-1);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
invalidate_mapping_pages(rc->data_inode->i_mapping,
|
|
0, -1);
|
|
rc->stage = UPDATE_DATA_PTRS;
|
|
}
|
|
}
|
|
|
|
WARN_ON(rc->block_group->pinned > 0);
|
|
WARN_ON(rc->block_group->reserved > 0);
|
|
WARN_ON(btrfs_block_group_used(&rc->block_group->item) > 0);
|
|
out:
|
|
if (err && rw)
|
|
btrfs_dec_block_group_ro(extent_root, rc->block_group);
|
|
iput(rc->data_inode);
|
|
btrfs_put_block_group(rc->block_group);
|
|
kfree(rc);
|
|
return err;
|
|
}
|
|
|
|
static noinline_for_stack int mark_garbage_root(struct btrfs_root *root)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
int ret, err;
|
|
|
|
trans = btrfs_start_transaction(root->fs_info->tree_root, 0);
|
|
if (IS_ERR(trans))
|
|
return PTR_ERR(trans);
|
|
|
|
memset(&root->root_item.drop_progress, 0,
|
|
sizeof(root->root_item.drop_progress));
|
|
root->root_item.drop_level = 0;
|
|
btrfs_set_root_refs(&root->root_item, 0);
|
|
ret = btrfs_update_root(trans, root->fs_info->tree_root,
|
|
&root->root_key, &root->root_item);
|
|
|
|
err = btrfs_end_transaction(trans, root->fs_info->tree_root);
|
|
if (err)
|
|
return err;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* recover relocation interrupted by system crash.
|
|
*
|
|
* this function resumes merging reloc trees with corresponding fs trees.
|
|
* this is important for keeping the sharing of tree blocks
|
|
*/
|
|
int btrfs_recover_relocation(struct btrfs_root *root)
|
|
{
|
|
LIST_HEAD(reloc_roots);
|
|
struct btrfs_key key;
|
|
struct btrfs_root *fs_root;
|
|
struct btrfs_root *reloc_root;
|
|
struct btrfs_path *path;
|
|
struct extent_buffer *leaf;
|
|
struct reloc_control *rc = NULL;
|
|
struct btrfs_trans_handle *trans;
|
|
int ret;
|
|
int err = 0;
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
path->reada = -1;
|
|
|
|
key.objectid = BTRFS_TREE_RELOC_OBJECTID;
|
|
key.type = BTRFS_ROOT_ITEM_KEY;
|
|
key.offset = (u64)-1;
|
|
|
|
while (1) {
|
|
ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key,
|
|
path, 0, 0);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
if (ret > 0) {
|
|
if (path->slots[0] == 0)
|
|
break;
|
|
path->slots[0]--;
|
|
}
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
btrfs_release_path(path);
|
|
|
|
if (key.objectid != BTRFS_TREE_RELOC_OBJECTID ||
|
|
key.type != BTRFS_ROOT_ITEM_KEY)
|
|
break;
|
|
|
|
reloc_root = btrfs_read_fs_root(root, &key);
|
|
if (IS_ERR(reloc_root)) {
|
|
err = PTR_ERR(reloc_root);
|
|
goto out;
|
|
}
|
|
|
|
list_add(&reloc_root->root_list, &reloc_roots);
|
|
|
|
if (btrfs_root_refs(&reloc_root->root_item) > 0) {
|
|
fs_root = read_fs_root(root->fs_info,
|
|
reloc_root->root_key.offset);
|
|
if (IS_ERR(fs_root)) {
|
|
ret = PTR_ERR(fs_root);
|
|
if (ret != -ENOENT) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
ret = mark_garbage_root(reloc_root);
|
|
if (ret < 0) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (key.offset == 0)
|
|
break;
|
|
|
|
key.offset--;
|
|
}
|
|
btrfs_release_path(path);
|
|
|
|
if (list_empty(&reloc_roots))
|
|
goto out;
|
|
|
|
rc = alloc_reloc_control(root->fs_info);
|
|
if (!rc) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
rc->extent_root = root->fs_info->extent_root;
|
|
|
|
set_reloc_control(rc);
|
|
|
|
trans = btrfs_join_transaction(rc->extent_root);
|
|
if (IS_ERR(trans)) {
|
|
unset_reloc_control(rc);
|
|
err = PTR_ERR(trans);
|
|
goto out_free;
|
|
}
|
|
|
|
rc->merge_reloc_tree = 1;
|
|
|
|
while (!list_empty(&reloc_roots)) {
|
|
reloc_root = list_entry(reloc_roots.next,
|
|
struct btrfs_root, root_list);
|
|
list_del(&reloc_root->root_list);
|
|
|
|
if (btrfs_root_refs(&reloc_root->root_item) == 0) {
|
|
list_add_tail(&reloc_root->root_list,
|
|
&rc->reloc_roots);
|
|
continue;
|
|
}
|
|
|
|
fs_root = read_fs_root(root->fs_info,
|
|
reloc_root->root_key.offset);
|
|
if (IS_ERR(fs_root)) {
|
|
err = PTR_ERR(fs_root);
|
|
goto out_free;
|
|
}
|
|
|
|
err = __add_reloc_root(reloc_root);
|
|
BUG_ON(err < 0); /* -ENOMEM or logic error */
|
|
fs_root->reloc_root = reloc_root;
|
|
}
|
|
|
|
err = btrfs_commit_transaction(trans, rc->extent_root);
|
|
if (err)
|
|
goto out_free;
|
|
|
|
merge_reloc_roots(rc);
|
|
|
|
unset_reloc_control(rc);
|
|
|
|
trans = btrfs_join_transaction(rc->extent_root);
|
|
if (IS_ERR(trans))
|
|
err = PTR_ERR(trans);
|
|
else
|
|
err = btrfs_commit_transaction(trans, rc->extent_root);
|
|
out_free:
|
|
kfree(rc);
|
|
out:
|
|
if (!list_empty(&reloc_roots))
|
|
free_reloc_roots(&reloc_roots);
|
|
|
|
btrfs_free_path(path);
|
|
|
|
if (err == 0) {
|
|
/* cleanup orphan inode in data relocation tree */
|
|
fs_root = read_fs_root(root->fs_info,
|
|
BTRFS_DATA_RELOC_TREE_OBJECTID);
|
|
if (IS_ERR(fs_root))
|
|
err = PTR_ERR(fs_root);
|
|
else
|
|
err = btrfs_orphan_cleanup(fs_root);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* helper to add ordered checksum for data relocation.
|
|
*
|
|
* cloning checksum properly handles the nodatasum extents.
|
|
* it also saves CPU time to re-calculate the checksum.
|
|
*/
|
|
int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
|
|
{
|
|
struct btrfs_ordered_sum *sums;
|
|
struct btrfs_ordered_extent *ordered;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
int ret;
|
|
u64 disk_bytenr;
|
|
u64 new_bytenr;
|
|
LIST_HEAD(list);
|
|
|
|
ordered = btrfs_lookup_ordered_extent(inode, file_pos);
|
|
BUG_ON(ordered->file_offset != file_pos || ordered->len != len);
|
|
|
|
disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt;
|
|
ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr,
|
|
disk_bytenr + len - 1, &list, 0);
|
|
if (ret)
|
|
goto out;
|
|
|
|
while (!list_empty(&list)) {
|
|
sums = list_entry(list.next, struct btrfs_ordered_sum, list);
|
|
list_del_init(&sums->list);
|
|
|
|
/*
|
|
* We need to offset the new_bytenr based on where the csum is.
|
|
* We need to do this because we will read in entire prealloc
|
|
* extents but we may have written to say the middle of the
|
|
* prealloc extent, so we need to make sure the csum goes with
|
|
* the right disk offset.
|
|
*
|
|
* We can do this because the data reloc inode refers strictly
|
|
* to the on disk bytes, so we don't have to worry about
|
|
* disk_len vs real len like with real inodes since it's all
|
|
* disk length.
|
|
*/
|
|
new_bytenr = ordered->start + (sums->bytenr - disk_bytenr);
|
|
sums->bytenr = new_bytenr;
|
|
|
|
btrfs_add_ordered_sum(inode, ordered, sums);
|
|
}
|
|
out:
|
|
btrfs_put_ordered_extent(ordered);
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root, struct extent_buffer *buf,
|
|
struct extent_buffer *cow)
|
|
{
|
|
struct reloc_control *rc;
|
|
struct backref_node *node;
|
|
int first_cow = 0;
|
|
int level;
|
|
int ret = 0;
|
|
|
|
rc = root->fs_info->reloc_ctl;
|
|
if (!rc)
|
|
return 0;
|
|
|
|
BUG_ON(rc->stage == UPDATE_DATA_PTRS &&
|
|
root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID);
|
|
|
|
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
|
|
if (buf == root->node)
|
|
__update_reloc_root(root, cow->start);
|
|
}
|
|
|
|
level = btrfs_header_level(buf);
|
|
if (btrfs_header_generation(buf) <=
|
|
btrfs_root_last_snapshot(&root->root_item))
|
|
first_cow = 1;
|
|
|
|
if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID &&
|
|
rc->create_reloc_tree) {
|
|
WARN_ON(!first_cow && level == 0);
|
|
|
|
node = rc->backref_cache.path[level];
|
|
BUG_ON(node->bytenr != buf->start &&
|
|
node->new_bytenr != buf->start);
|
|
|
|
drop_node_buffer(node);
|
|
extent_buffer_get(cow);
|
|
node->eb = cow;
|
|
node->new_bytenr = cow->start;
|
|
|
|
if (!node->pending) {
|
|
list_move_tail(&node->list,
|
|
&rc->backref_cache.pending[level]);
|
|
node->pending = 1;
|
|
}
|
|
|
|
if (first_cow)
|
|
__mark_block_processed(rc, node);
|
|
|
|
if (first_cow && level > 0)
|
|
rc->nodes_relocated += buf->len;
|
|
}
|
|
|
|
if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS)
|
|
ret = replace_file_extents(trans, rc, root, cow);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* called before creating snapshot. it calculates metadata reservation
|
|
* requried for relocating tree blocks in the snapshot
|
|
*/
|
|
void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending,
|
|
u64 *bytes_to_reserve)
|
|
{
|
|
struct btrfs_root *root;
|
|
struct reloc_control *rc;
|
|
|
|
root = pending->root;
|
|
if (!root->reloc_root)
|
|
return;
|
|
|
|
rc = root->fs_info->reloc_ctl;
|
|
if (!rc->merge_reloc_tree)
|
|
return;
|
|
|
|
root = root->reloc_root;
|
|
BUG_ON(btrfs_root_refs(&root->root_item) == 0);
|
|
/*
|
|
* relocation is in the stage of merging trees. the space
|
|
* used by merging a reloc tree is twice the size of
|
|
* relocated tree nodes in the worst case. half for cowing
|
|
* the reloc tree, half for cowing the fs tree. the space
|
|
* used by cowing the reloc tree will be freed after the
|
|
* tree is dropped. if we create snapshot, cowing the fs
|
|
* tree may use more space than it frees. so we need
|
|
* reserve extra space.
|
|
*/
|
|
*bytes_to_reserve += rc->nodes_relocated;
|
|
}
|
|
|
|
/*
|
|
* called after snapshot is created. migrate block reservation
|
|
* and create reloc root for the newly created snapshot
|
|
*/
|
|
int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans,
|
|
struct btrfs_pending_snapshot *pending)
|
|
{
|
|
struct btrfs_root *root = pending->root;
|
|
struct btrfs_root *reloc_root;
|
|
struct btrfs_root *new_root;
|
|
struct reloc_control *rc;
|
|
int ret;
|
|
|
|
if (!root->reloc_root)
|
|
return 0;
|
|
|
|
rc = root->fs_info->reloc_ctl;
|
|
rc->merging_rsv_size += rc->nodes_relocated;
|
|
|
|
if (rc->merge_reloc_tree) {
|
|
ret = btrfs_block_rsv_migrate(&pending->block_rsv,
|
|
rc->block_rsv,
|
|
rc->nodes_relocated);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
new_root = pending->snap;
|
|
reloc_root = create_reloc_root(trans, root->reloc_root,
|
|
new_root->root_key.objectid);
|
|
if (IS_ERR(reloc_root))
|
|
return PTR_ERR(reloc_root);
|
|
|
|
ret = __add_reloc_root(reloc_root);
|
|
BUG_ON(ret < 0);
|
|
new_root->reloc_root = reloc_root;
|
|
|
|
if (rc->create_reloc_tree)
|
|
ret = clone_backref_node(trans, rc, root, reloc_root);
|
|
return ret;
|
|
}
|