1c1d7c514SDavid Sterba // SPDX-License-Identifier: GPL-2.0 25d4f98a2SYan Zheng /* 35d4f98a2SYan Zheng * Copyright (C) 2009 Oracle. All rights reserved. 45d4f98a2SYan Zheng */ 55d4f98a2SYan Zheng 65d4f98a2SYan Zheng #include <linux/sched.h> 75d4f98a2SYan Zheng #include <linux/pagemap.h> 85d4f98a2SYan Zheng #include <linux/writeback.h> 95d4f98a2SYan Zheng #include <linux/blkdev.h> 105d4f98a2SYan Zheng #include <linux/rbtree.h> 115a0e3ad6STejun Heo #include <linux/slab.h> 12726a3421SQu Wenruo #include <linux/error-injection.h> 135d4f98a2SYan Zheng #include "ctree.h" 145d4f98a2SYan Zheng #include "disk-io.h" 155d4f98a2SYan Zheng #include "transaction.h" 165d4f98a2SYan Zheng #include "volumes.h" 175d4f98a2SYan Zheng #include "locking.h" 185d4f98a2SYan Zheng #include "btrfs_inode.h" 195d4f98a2SYan Zheng #include "async-thread.h" 200af3d00bSJosef Bacik #include "free-space-cache.h" 21581bb050SLi Zefan #include "inode-map.h" 2262b99540SQu Wenruo #include "qgroup.h" 23cdccee99SLiu Bo #include "print-tree.h" 2486736342SJosef Bacik #include "delalloc-space.h" 25aac0023cSJosef Bacik #include "block-group.h" 2619b546d7SQu Wenruo #include "backref.h" 275d4f98a2SYan Zheng 285d4f98a2SYan Zheng /* 290c891389SQu Wenruo * Relocation overview 300c891389SQu Wenruo * 310c891389SQu Wenruo * [What does relocation do] 320c891389SQu Wenruo * 330c891389SQu Wenruo * The objective of relocation is to relocate all extents of the target block 340c891389SQu Wenruo * group to other block groups. 350c891389SQu Wenruo * This is utilized by resize (shrink only), profile converting, compacting 360c891389SQu Wenruo * space, or balance routine to spread chunks over devices. 370c891389SQu Wenruo * 380c891389SQu Wenruo * Before | After 390c891389SQu Wenruo * ------------------------------------------------------------------ 400c891389SQu Wenruo * BG A: 10 data extents | BG A: deleted 410c891389SQu Wenruo * BG B: 2 data extents | BG B: 10 data extents (2 old + 8 relocated) 420c891389SQu Wenruo * BG C: 1 extents | BG C: 3 data extents (1 old + 2 relocated) 430c891389SQu Wenruo * 440c891389SQu Wenruo * [How does relocation work] 450c891389SQu Wenruo * 460c891389SQu Wenruo * 1. Mark the target block group read-only 470c891389SQu Wenruo * New extents won't be allocated from the target block group. 480c891389SQu Wenruo * 490c891389SQu Wenruo * 2.1 Record each extent in the target block group 500c891389SQu Wenruo * To build a proper map of extents to be relocated. 510c891389SQu Wenruo * 520c891389SQu Wenruo * 2.2 Build data reloc tree and reloc trees 530c891389SQu Wenruo * Data reloc tree will contain an inode, recording all newly relocated 540c891389SQu Wenruo * data extents. 550c891389SQu Wenruo * There will be only one data reloc tree for one data block group. 560c891389SQu Wenruo * 570c891389SQu Wenruo * Reloc tree will be a special snapshot of its source tree, containing 580c891389SQu Wenruo * relocated tree blocks. 590c891389SQu Wenruo * Each tree referring to a tree block in target block group will get its 600c891389SQu Wenruo * reloc tree built. 610c891389SQu Wenruo * 620c891389SQu Wenruo * 2.3 Swap source tree with its corresponding reloc tree 630c891389SQu Wenruo * Each involved tree only refers to new extents after swap. 640c891389SQu Wenruo * 650c891389SQu Wenruo * 3. Cleanup reloc trees and data reloc tree. 660c891389SQu Wenruo * As old extents in the target block group are still referenced by reloc 670c891389SQu Wenruo * trees, we need to clean them up before really freeing the target block 680c891389SQu Wenruo * group. 690c891389SQu Wenruo * 700c891389SQu Wenruo * The main complexity is in steps 2.2 and 2.3. 710c891389SQu Wenruo * 720c891389SQu Wenruo * The entry point of relocation is relocate_block_group() function. 730c891389SQu Wenruo */ 740c891389SQu Wenruo 750c891389SQu Wenruo /* 765d4f98a2SYan Zheng * backref_node, mapping_node and tree_block start with this 775d4f98a2SYan Zheng */ 785d4f98a2SYan Zheng struct tree_entry { 795d4f98a2SYan Zheng struct rb_node rb_node; 805d4f98a2SYan Zheng u64 bytenr; 815d4f98a2SYan Zheng }; 825d4f98a2SYan Zheng 835d4f98a2SYan Zheng /* 845d4f98a2SYan Zheng * present a tree block in the backref cache 855d4f98a2SYan Zheng */ 865d4f98a2SYan Zheng struct backref_node { 875d4f98a2SYan Zheng struct rb_node rb_node; 885d4f98a2SYan Zheng u64 bytenr; 893fd0a558SYan, Zheng 903fd0a558SYan, Zheng u64 new_bytenr; 913fd0a558SYan, Zheng /* objectid of tree block owner, can be not uptodate */ 925d4f98a2SYan Zheng u64 owner; 933fd0a558SYan, Zheng /* link to pending, changed or detached list */ 943fd0a558SYan, Zheng struct list_head list; 955d4f98a2SYan Zheng /* list of upper level blocks reference this block */ 965d4f98a2SYan Zheng struct list_head upper; 975d4f98a2SYan Zheng /* list of child blocks in the cache */ 985d4f98a2SYan Zheng struct list_head lower; 995d4f98a2SYan Zheng /* NULL if this node is not tree root */ 1005d4f98a2SYan Zheng struct btrfs_root *root; 1015d4f98a2SYan Zheng /* extent buffer got by COW the block */ 1025d4f98a2SYan Zheng struct extent_buffer *eb; 1035d4f98a2SYan Zheng /* level of tree block */ 1045d4f98a2SYan Zheng unsigned int level:8; 1053fd0a558SYan, Zheng /* is the block in non-reference counted tree */ 1063fd0a558SYan, Zheng unsigned int cowonly:1; 1073fd0a558SYan, Zheng /* 1 if no child node in the cache */ 1085d4f98a2SYan Zheng unsigned int lowest:1; 1095d4f98a2SYan Zheng /* is the extent buffer locked */ 1105d4f98a2SYan Zheng unsigned int locked:1; 1115d4f98a2SYan Zheng /* has the block been processed */ 1125d4f98a2SYan Zheng unsigned int processed:1; 1135d4f98a2SYan Zheng /* have backrefs of this block been checked */ 1145d4f98a2SYan Zheng unsigned int checked:1; 1153fd0a558SYan, Zheng /* 1163fd0a558SYan, Zheng * 1 if corresponding block has been cowed but some upper 1173fd0a558SYan, Zheng * level block pointers may not point to the new location 1183fd0a558SYan, Zheng */ 1193fd0a558SYan, Zheng unsigned int pending:1; 1203fd0a558SYan, Zheng /* 1213fd0a558SYan, Zheng * 1 if the backref node isn't connected to any other 1223fd0a558SYan, Zheng * backref node. 1233fd0a558SYan, Zheng */ 1243fd0a558SYan, Zheng unsigned int detached:1; 1255d4f98a2SYan Zheng }; 1265d4f98a2SYan Zheng 1275d4f98a2SYan Zheng /* 1285d4f98a2SYan Zheng * present a block pointer in the backref cache 1295d4f98a2SYan Zheng */ 1305d4f98a2SYan Zheng struct backref_edge { 1315d4f98a2SYan Zheng struct list_head list[2]; 1325d4f98a2SYan Zheng struct backref_node *node[2]; 1335d4f98a2SYan Zheng }; 1345d4f98a2SYan Zheng 1355d4f98a2SYan Zheng #define LOWER 0 1365d4f98a2SYan Zheng #define UPPER 1 1370647bf56SWang Shilong #define RELOCATION_RESERVED_NODES 256 1385d4f98a2SYan Zheng 1395d4f98a2SYan Zheng struct backref_cache { 1405d4f98a2SYan Zheng /* red black tree of all backref nodes in the cache */ 1415d4f98a2SYan Zheng struct rb_root rb_root; 1423fd0a558SYan, Zheng /* for passing backref nodes to btrfs_reloc_cow_block */ 1433fd0a558SYan, Zheng struct backref_node *path[BTRFS_MAX_LEVEL]; 1443fd0a558SYan, Zheng /* 1453fd0a558SYan, Zheng * list of blocks that have been cowed but some block 1463fd0a558SYan, Zheng * pointers in upper level blocks may not reflect the 1473fd0a558SYan, Zheng * new location 1483fd0a558SYan, Zheng */ 1495d4f98a2SYan Zheng struct list_head pending[BTRFS_MAX_LEVEL]; 1503fd0a558SYan, Zheng /* list of backref nodes with no child node */ 1513fd0a558SYan, Zheng struct list_head leaves; 1523fd0a558SYan, Zheng /* list of blocks that have been cowed in current transaction */ 1533fd0a558SYan, Zheng struct list_head changed; 1543fd0a558SYan, Zheng /* list of detached backref node. */ 1553fd0a558SYan, Zheng struct list_head detached; 1563fd0a558SYan, Zheng 1573fd0a558SYan, Zheng u64 last_trans; 1583fd0a558SYan, Zheng 1593fd0a558SYan, Zheng int nr_nodes; 1603fd0a558SYan, Zheng int nr_edges; 1615d4f98a2SYan Zheng }; 1625d4f98a2SYan Zheng 1635d4f98a2SYan Zheng /* 1645d4f98a2SYan Zheng * map address of tree root to tree 1655d4f98a2SYan Zheng */ 1665d4f98a2SYan Zheng struct mapping_node { 1675d4f98a2SYan Zheng struct rb_node rb_node; 1685d4f98a2SYan Zheng u64 bytenr; 1695d4f98a2SYan Zheng void *data; 1705d4f98a2SYan Zheng }; 1715d4f98a2SYan Zheng 1725d4f98a2SYan Zheng struct mapping_tree { 1735d4f98a2SYan Zheng struct rb_root rb_root; 1745d4f98a2SYan Zheng spinlock_t lock; 1755d4f98a2SYan Zheng }; 1765d4f98a2SYan Zheng 1775d4f98a2SYan Zheng /* 1785d4f98a2SYan Zheng * present a tree block to process 1795d4f98a2SYan Zheng */ 1805d4f98a2SYan Zheng struct tree_block { 1815d4f98a2SYan Zheng struct rb_node rb_node; 1825d4f98a2SYan Zheng u64 bytenr; 1835d4f98a2SYan Zheng struct btrfs_key key; 1845d4f98a2SYan Zheng unsigned int level:8; 1855d4f98a2SYan Zheng unsigned int key_ready:1; 1865d4f98a2SYan Zheng }; 1875d4f98a2SYan Zheng 1880257bb82SYan, Zheng #define MAX_EXTENTS 128 1890257bb82SYan, Zheng 1900257bb82SYan, Zheng struct file_extent_cluster { 1910257bb82SYan, Zheng u64 start; 1920257bb82SYan, Zheng u64 end; 1930257bb82SYan, Zheng u64 boundary[MAX_EXTENTS]; 1940257bb82SYan, Zheng unsigned int nr; 1950257bb82SYan, Zheng }; 1960257bb82SYan, Zheng 1975d4f98a2SYan Zheng struct reloc_control { 1985d4f98a2SYan Zheng /* block group to relocate */ 19932da5386SDavid Sterba struct btrfs_block_group *block_group; 2005d4f98a2SYan Zheng /* extent tree */ 2015d4f98a2SYan Zheng struct btrfs_root *extent_root; 2025d4f98a2SYan Zheng /* inode for moving data */ 2035d4f98a2SYan Zheng struct inode *data_inode; 2043fd0a558SYan, Zheng 2053fd0a558SYan, Zheng struct btrfs_block_rsv *block_rsv; 2063fd0a558SYan, Zheng 2073fd0a558SYan, Zheng struct backref_cache backref_cache; 2083fd0a558SYan, Zheng 2093fd0a558SYan, Zheng struct file_extent_cluster cluster; 2105d4f98a2SYan Zheng /* tree blocks have been processed */ 2115d4f98a2SYan Zheng struct extent_io_tree processed_blocks; 2125d4f98a2SYan Zheng /* map start of tree root to corresponding reloc tree */ 2135d4f98a2SYan Zheng struct mapping_tree reloc_root_tree; 2145d4f98a2SYan Zheng /* list of reloc trees */ 2155d4f98a2SYan Zheng struct list_head reloc_roots; 216d2311e69SQu Wenruo /* list of subvolume trees that get relocated */ 217d2311e69SQu Wenruo struct list_head dirty_subvol_roots; 2183fd0a558SYan, Zheng /* size of metadata reservation for merging reloc trees */ 2193fd0a558SYan, Zheng u64 merging_rsv_size; 2203fd0a558SYan, Zheng /* size of relocated tree nodes */ 2213fd0a558SYan, Zheng u64 nodes_relocated; 2220647bf56SWang Shilong /* reserved size for block group relocation*/ 2230647bf56SWang Shilong u64 reserved_bytes; 2243fd0a558SYan, Zheng 2255d4f98a2SYan Zheng u64 search_start; 2265d4f98a2SYan Zheng u64 extents_found; 2273fd0a558SYan, Zheng 2283fd0a558SYan, Zheng unsigned int stage:8; 2293fd0a558SYan, Zheng unsigned int create_reloc_tree:1; 2303fd0a558SYan, Zheng unsigned int merge_reloc_tree:1; 2315d4f98a2SYan Zheng unsigned int found_file_extent:1; 2325d4f98a2SYan Zheng }; 2335d4f98a2SYan Zheng 2345d4f98a2SYan Zheng /* stages of data relocation */ 2355d4f98a2SYan Zheng #define MOVE_DATA_EXTENTS 0 2365d4f98a2SYan Zheng #define UPDATE_DATA_PTRS 1 2375d4f98a2SYan Zheng 2383fd0a558SYan, Zheng static void remove_backref_node(struct backref_cache *cache, 2393fd0a558SYan, Zheng struct backref_node *node); 2403fd0a558SYan, Zheng static void __mark_block_processed(struct reloc_control *rc, 2413fd0a558SYan, Zheng struct backref_node *node); 2425d4f98a2SYan Zheng 2435d4f98a2SYan Zheng static void mapping_tree_init(struct mapping_tree *tree) 2445d4f98a2SYan Zheng { 2456bef4d31SEric Paris tree->rb_root = RB_ROOT; 2465d4f98a2SYan Zheng spin_lock_init(&tree->lock); 2475d4f98a2SYan Zheng } 2485d4f98a2SYan Zheng 2495d4f98a2SYan Zheng static void backref_cache_init(struct backref_cache *cache) 2505d4f98a2SYan Zheng { 2515d4f98a2SYan Zheng int i; 2526bef4d31SEric Paris cache->rb_root = RB_ROOT; 2535d4f98a2SYan Zheng for (i = 0; i < BTRFS_MAX_LEVEL; i++) 2545d4f98a2SYan Zheng INIT_LIST_HEAD(&cache->pending[i]); 2553fd0a558SYan, Zheng INIT_LIST_HEAD(&cache->changed); 2563fd0a558SYan, Zheng INIT_LIST_HEAD(&cache->detached); 2573fd0a558SYan, Zheng INIT_LIST_HEAD(&cache->leaves); 2585d4f98a2SYan Zheng } 2595d4f98a2SYan Zheng 2603fd0a558SYan, Zheng static void backref_cache_cleanup(struct backref_cache *cache) 2615d4f98a2SYan Zheng { 2623fd0a558SYan, Zheng struct backref_node *node; 2633fd0a558SYan, Zheng int i; 2643fd0a558SYan, Zheng 2653fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 2663fd0a558SYan, Zheng node = list_entry(cache->detached.next, 2673fd0a558SYan, Zheng struct backref_node, list); 2683fd0a558SYan, Zheng remove_backref_node(cache, node); 2693fd0a558SYan, Zheng } 2703fd0a558SYan, Zheng 2713fd0a558SYan, Zheng while (!list_empty(&cache->leaves)) { 2723fd0a558SYan, Zheng node = list_entry(cache->leaves.next, 2733fd0a558SYan, Zheng struct backref_node, lower); 2743fd0a558SYan, Zheng remove_backref_node(cache, node); 2753fd0a558SYan, Zheng } 2763fd0a558SYan, Zheng 2773fd0a558SYan, Zheng cache->last_trans = 0; 2783fd0a558SYan, Zheng 2793fd0a558SYan, Zheng for (i = 0; i < BTRFS_MAX_LEVEL; i++) 280f4907095SLiu Bo ASSERT(list_empty(&cache->pending[i])); 281f4907095SLiu Bo ASSERT(list_empty(&cache->changed)); 282f4907095SLiu Bo ASSERT(list_empty(&cache->detached)); 283f4907095SLiu Bo ASSERT(RB_EMPTY_ROOT(&cache->rb_root)); 284f4907095SLiu Bo ASSERT(!cache->nr_nodes); 285f4907095SLiu Bo ASSERT(!cache->nr_edges); 2863fd0a558SYan, Zheng } 2873fd0a558SYan, Zheng 2883fd0a558SYan, Zheng static struct backref_node *alloc_backref_node(struct backref_cache *cache) 2893fd0a558SYan, Zheng { 2903fd0a558SYan, Zheng struct backref_node *node; 2913fd0a558SYan, Zheng 2923fd0a558SYan, Zheng node = kzalloc(sizeof(*node), GFP_NOFS); 2933fd0a558SYan, Zheng if (node) { 2943fd0a558SYan, Zheng INIT_LIST_HEAD(&node->list); 2955d4f98a2SYan Zheng INIT_LIST_HEAD(&node->upper); 2965d4f98a2SYan Zheng INIT_LIST_HEAD(&node->lower); 2975d4f98a2SYan Zheng RB_CLEAR_NODE(&node->rb_node); 2983fd0a558SYan, Zheng cache->nr_nodes++; 2993fd0a558SYan, Zheng } 3003fd0a558SYan, Zheng return node; 3013fd0a558SYan, Zheng } 3023fd0a558SYan, Zheng 3033fd0a558SYan, Zheng static void free_backref_node(struct backref_cache *cache, 3043fd0a558SYan, Zheng struct backref_node *node) 3053fd0a558SYan, Zheng { 3063fd0a558SYan, Zheng if (node) { 3073fd0a558SYan, Zheng cache->nr_nodes--; 30800246528SJosef Bacik btrfs_put_root(node->root); 3093fd0a558SYan, Zheng kfree(node); 3103fd0a558SYan, Zheng } 3113fd0a558SYan, Zheng } 3123fd0a558SYan, Zheng 3133fd0a558SYan, Zheng static struct backref_edge *alloc_backref_edge(struct backref_cache *cache) 3143fd0a558SYan, Zheng { 3153fd0a558SYan, Zheng struct backref_edge *edge; 3163fd0a558SYan, Zheng 3173fd0a558SYan, Zheng edge = kzalloc(sizeof(*edge), GFP_NOFS); 3183fd0a558SYan, Zheng if (edge) 3193fd0a558SYan, Zheng cache->nr_edges++; 3203fd0a558SYan, Zheng return edge; 3213fd0a558SYan, Zheng } 3223fd0a558SYan, Zheng 3233fd0a558SYan, Zheng static void free_backref_edge(struct backref_cache *cache, 3243fd0a558SYan, Zheng struct backref_edge *edge) 3253fd0a558SYan, Zheng { 3263fd0a558SYan, Zheng if (edge) { 3273fd0a558SYan, Zheng cache->nr_edges--; 3283fd0a558SYan, Zheng kfree(edge); 3293fd0a558SYan, Zheng } 3305d4f98a2SYan Zheng } 3315d4f98a2SYan Zheng 3325d4f98a2SYan Zheng static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr, 3335d4f98a2SYan Zheng struct rb_node *node) 3345d4f98a2SYan Zheng { 3355d4f98a2SYan Zheng struct rb_node **p = &root->rb_node; 3365d4f98a2SYan Zheng struct rb_node *parent = NULL; 3375d4f98a2SYan Zheng struct tree_entry *entry; 3385d4f98a2SYan Zheng 3395d4f98a2SYan Zheng while (*p) { 3405d4f98a2SYan Zheng parent = *p; 3415d4f98a2SYan Zheng entry = rb_entry(parent, struct tree_entry, rb_node); 3425d4f98a2SYan Zheng 3435d4f98a2SYan Zheng if (bytenr < entry->bytenr) 3445d4f98a2SYan Zheng p = &(*p)->rb_left; 3455d4f98a2SYan Zheng else if (bytenr > entry->bytenr) 3465d4f98a2SYan Zheng p = &(*p)->rb_right; 3475d4f98a2SYan Zheng else 3485d4f98a2SYan Zheng return parent; 3495d4f98a2SYan Zheng } 3505d4f98a2SYan Zheng 3515d4f98a2SYan Zheng rb_link_node(node, parent, p); 3525d4f98a2SYan Zheng rb_insert_color(node, root); 3535d4f98a2SYan Zheng return NULL; 3545d4f98a2SYan Zheng } 3555d4f98a2SYan Zheng 3565d4f98a2SYan Zheng static struct rb_node *tree_search(struct rb_root *root, u64 bytenr) 3575d4f98a2SYan Zheng { 3585d4f98a2SYan Zheng struct rb_node *n = root->rb_node; 3595d4f98a2SYan Zheng struct tree_entry *entry; 3605d4f98a2SYan Zheng 3615d4f98a2SYan Zheng while (n) { 3625d4f98a2SYan Zheng entry = rb_entry(n, struct tree_entry, rb_node); 3635d4f98a2SYan Zheng 3645d4f98a2SYan Zheng if (bytenr < entry->bytenr) 3655d4f98a2SYan Zheng n = n->rb_left; 3665d4f98a2SYan Zheng else if (bytenr > entry->bytenr) 3675d4f98a2SYan Zheng n = n->rb_right; 3685d4f98a2SYan Zheng else 3695d4f98a2SYan Zheng return n; 3705d4f98a2SYan Zheng } 3715d4f98a2SYan Zheng return NULL; 3725d4f98a2SYan Zheng } 3735d4f98a2SYan Zheng 37448a3b636SEric Sandeen static void backref_tree_panic(struct rb_node *rb_node, int errno, u64 bytenr) 37543c04fb1SJeff Mahoney { 37643c04fb1SJeff Mahoney 37743c04fb1SJeff Mahoney struct btrfs_fs_info *fs_info = NULL; 37843c04fb1SJeff Mahoney struct backref_node *bnode = rb_entry(rb_node, struct backref_node, 37943c04fb1SJeff Mahoney rb_node); 38043c04fb1SJeff Mahoney if (bnode->root) 38143c04fb1SJeff Mahoney fs_info = bnode->root->fs_info; 3825d163e0eSJeff Mahoney btrfs_panic(fs_info, errno, 3835d163e0eSJeff Mahoney "Inconsistency in backref cache found at offset %llu", 3845d163e0eSJeff Mahoney bytenr); 38543c04fb1SJeff Mahoney } 38643c04fb1SJeff Mahoney 3875d4f98a2SYan Zheng /* 3885d4f98a2SYan Zheng * walk up backref nodes until reach node presents tree root 3895d4f98a2SYan Zheng */ 3905d4f98a2SYan Zheng static struct backref_node *walk_up_backref(struct backref_node *node, 3915d4f98a2SYan Zheng struct backref_edge *edges[], 3925d4f98a2SYan Zheng int *index) 3935d4f98a2SYan Zheng { 3945d4f98a2SYan Zheng struct backref_edge *edge; 3955d4f98a2SYan Zheng int idx = *index; 3965d4f98a2SYan Zheng 3975d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 3985d4f98a2SYan Zheng edge = list_entry(node->upper.next, 3995d4f98a2SYan Zheng struct backref_edge, list[LOWER]); 4005d4f98a2SYan Zheng edges[idx++] = edge; 4015d4f98a2SYan Zheng node = edge->node[UPPER]; 4025d4f98a2SYan Zheng } 4033fd0a558SYan, Zheng BUG_ON(node->detached); 4045d4f98a2SYan Zheng *index = idx; 4055d4f98a2SYan Zheng return node; 4065d4f98a2SYan Zheng } 4075d4f98a2SYan Zheng 4085d4f98a2SYan Zheng /* 4095d4f98a2SYan Zheng * walk down backref nodes to find start of next reference path 4105d4f98a2SYan Zheng */ 4115d4f98a2SYan Zheng static struct backref_node *walk_down_backref(struct backref_edge *edges[], 4125d4f98a2SYan Zheng int *index) 4135d4f98a2SYan Zheng { 4145d4f98a2SYan Zheng struct backref_edge *edge; 4155d4f98a2SYan Zheng struct backref_node *lower; 4165d4f98a2SYan Zheng int idx = *index; 4175d4f98a2SYan Zheng 4185d4f98a2SYan Zheng while (idx > 0) { 4195d4f98a2SYan Zheng edge = edges[idx - 1]; 4205d4f98a2SYan Zheng lower = edge->node[LOWER]; 4215d4f98a2SYan Zheng if (list_is_last(&edge->list[LOWER], &lower->upper)) { 4225d4f98a2SYan Zheng idx--; 4235d4f98a2SYan Zheng continue; 4245d4f98a2SYan Zheng } 4255d4f98a2SYan Zheng edge = list_entry(edge->list[LOWER].next, 4265d4f98a2SYan Zheng struct backref_edge, list[LOWER]); 4275d4f98a2SYan Zheng edges[idx - 1] = edge; 4285d4f98a2SYan Zheng *index = idx; 4295d4f98a2SYan Zheng return edge->node[UPPER]; 4305d4f98a2SYan Zheng } 4315d4f98a2SYan Zheng *index = 0; 4325d4f98a2SYan Zheng return NULL; 4335d4f98a2SYan Zheng } 4345d4f98a2SYan Zheng 4353fd0a558SYan, Zheng static void unlock_node_buffer(struct backref_node *node) 4365d4f98a2SYan Zheng { 4375d4f98a2SYan Zheng if (node->locked) { 4385d4f98a2SYan Zheng btrfs_tree_unlock(node->eb); 4395d4f98a2SYan Zheng node->locked = 0; 4405d4f98a2SYan Zheng } 4413fd0a558SYan, Zheng } 4423fd0a558SYan, Zheng 4433fd0a558SYan, Zheng static void drop_node_buffer(struct backref_node *node) 4443fd0a558SYan, Zheng { 4453fd0a558SYan, Zheng if (node->eb) { 4463fd0a558SYan, Zheng unlock_node_buffer(node); 4475d4f98a2SYan Zheng free_extent_buffer(node->eb); 4485d4f98a2SYan Zheng node->eb = NULL; 4495d4f98a2SYan Zheng } 4505d4f98a2SYan Zheng } 4515d4f98a2SYan Zheng 4525d4f98a2SYan Zheng static void drop_backref_node(struct backref_cache *tree, 4535d4f98a2SYan Zheng struct backref_node *node) 4545d4f98a2SYan Zheng { 4555d4f98a2SYan Zheng BUG_ON(!list_empty(&node->upper)); 4565d4f98a2SYan Zheng 4575d4f98a2SYan Zheng drop_node_buffer(node); 4583fd0a558SYan, Zheng list_del(&node->list); 4595d4f98a2SYan Zheng list_del(&node->lower); 4603fd0a558SYan, Zheng if (!RB_EMPTY_NODE(&node->rb_node)) 4615d4f98a2SYan Zheng rb_erase(&node->rb_node, &tree->rb_root); 4623fd0a558SYan, Zheng free_backref_node(tree, node); 4635d4f98a2SYan Zheng } 4645d4f98a2SYan Zheng 4655d4f98a2SYan Zheng /* 4665d4f98a2SYan Zheng * remove a backref node from the backref cache 4675d4f98a2SYan Zheng */ 4685d4f98a2SYan Zheng static void remove_backref_node(struct backref_cache *cache, 4695d4f98a2SYan Zheng struct backref_node *node) 4705d4f98a2SYan Zheng { 4715d4f98a2SYan Zheng struct backref_node *upper; 4725d4f98a2SYan Zheng struct backref_edge *edge; 4735d4f98a2SYan Zheng 4745d4f98a2SYan Zheng if (!node) 4755d4f98a2SYan Zheng return; 4765d4f98a2SYan Zheng 4773fd0a558SYan, Zheng BUG_ON(!node->lowest && !node->detached); 4785d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 4795d4f98a2SYan Zheng edge = list_entry(node->upper.next, struct backref_edge, 4805d4f98a2SYan Zheng list[LOWER]); 4815d4f98a2SYan Zheng upper = edge->node[UPPER]; 4825d4f98a2SYan Zheng list_del(&edge->list[LOWER]); 4835d4f98a2SYan Zheng list_del(&edge->list[UPPER]); 4843fd0a558SYan, Zheng free_backref_edge(cache, edge); 4853fd0a558SYan, Zheng 4863fd0a558SYan, Zheng if (RB_EMPTY_NODE(&upper->rb_node)) { 4873fd0a558SYan, Zheng BUG_ON(!list_empty(&node->upper)); 4883fd0a558SYan, Zheng drop_backref_node(cache, node); 4893fd0a558SYan, Zheng node = upper; 4903fd0a558SYan, Zheng node->lowest = 1; 4913fd0a558SYan, Zheng continue; 4923fd0a558SYan, Zheng } 4935d4f98a2SYan Zheng /* 4943fd0a558SYan, Zheng * add the node to leaf node list if no other 4955d4f98a2SYan Zheng * child block cached. 4965d4f98a2SYan Zheng */ 4975d4f98a2SYan Zheng if (list_empty(&upper->lower)) { 4983fd0a558SYan, Zheng list_add_tail(&upper->lower, &cache->leaves); 4995d4f98a2SYan Zheng upper->lowest = 1; 5005d4f98a2SYan Zheng } 5015d4f98a2SYan Zheng } 5023fd0a558SYan, Zheng 5035d4f98a2SYan Zheng drop_backref_node(cache, node); 5045d4f98a2SYan Zheng } 5055d4f98a2SYan Zheng 5063fd0a558SYan, Zheng static void update_backref_node(struct backref_cache *cache, 5073fd0a558SYan, Zheng struct backref_node *node, u64 bytenr) 5083fd0a558SYan, Zheng { 5093fd0a558SYan, Zheng struct rb_node *rb_node; 5103fd0a558SYan, Zheng rb_erase(&node->rb_node, &cache->rb_root); 5113fd0a558SYan, Zheng node->bytenr = bytenr; 5123fd0a558SYan, Zheng rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node); 51343c04fb1SJeff Mahoney if (rb_node) 51443c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, bytenr); 5153fd0a558SYan, Zheng } 5163fd0a558SYan, Zheng 5173fd0a558SYan, Zheng /* 5183fd0a558SYan, Zheng * update backref cache after a transaction commit 5193fd0a558SYan, Zheng */ 5203fd0a558SYan, Zheng static int update_backref_cache(struct btrfs_trans_handle *trans, 5213fd0a558SYan, Zheng struct backref_cache *cache) 5223fd0a558SYan, Zheng { 5233fd0a558SYan, Zheng struct backref_node *node; 5243fd0a558SYan, Zheng int level = 0; 5253fd0a558SYan, Zheng 5263fd0a558SYan, Zheng if (cache->last_trans == 0) { 5273fd0a558SYan, Zheng cache->last_trans = trans->transid; 5283fd0a558SYan, Zheng return 0; 5293fd0a558SYan, Zheng } 5303fd0a558SYan, Zheng 5313fd0a558SYan, Zheng if (cache->last_trans == trans->transid) 5323fd0a558SYan, Zheng return 0; 5333fd0a558SYan, Zheng 5343fd0a558SYan, Zheng /* 5353fd0a558SYan, Zheng * detached nodes are used to avoid unnecessary backref 5363fd0a558SYan, Zheng * lookup. transaction commit changes the extent tree. 5373fd0a558SYan, Zheng * so the detached nodes are no longer useful. 5383fd0a558SYan, Zheng */ 5393fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 5403fd0a558SYan, Zheng node = list_entry(cache->detached.next, 5413fd0a558SYan, Zheng struct backref_node, list); 5423fd0a558SYan, Zheng remove_backref_node(cache, node); 5433fd0a558SYan, Zheng } 5443fd0a558SYan, Zheng 5453fd0a558SYan, Zheng while (!list_empty(&cache->changed)) { 5463fd0a558SYan, Zheng node = list_entry(cache->changed.next, 5473fd0a558SYan, Zheng struct backref_node, list); 5483fd0a558SYan, Zheng list_del_init(&node->list); 5493fd0a558SYan, Zheng BUG_ON(node->pending); 5503fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 5513fd0a558SYan, Zheng } 5523fd0a558SYan, Zheng 5533fd0a558SYan, Zheng /* 5543fd0a558SYan, Zheng * some nodes can be left in the pending list if there were 5553fd0a558SYan, Zheng * errors during processing the pending nodes. 5563fd0a558SYan, Zheng */ 5573fd0a558SYan, Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 5583fd0a558SYan, Zheng list_for_each_entry(node, &cache->pending[level], list) { 5593fd0a558SYan, Zheng BUG_ON(!node->pending); 5603fd0a558SYan, Zheng if (node->bytenr == node->new_bytenr) 5613fd0a558SYan, Zheng continue; 5623fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 5633fd0a558SYan, Zheng } 5643fd0a558SYan, Zheng } 5653fd0a558SYan, Zheng 5663fd0a558SYan, Zheng cache->last_trans = 0; 5673fd0a558SYan, Zheng return 1; 5683fd0a558SYan, Zheng } 5693fd0a558SYan, Zheng 5706282675eSQu Wenruo static bool reloc_root_is_dead(struct btrfs_root *root) 5716282675eSQu Wenruo { 5726282675eSQu Wenruo /* 5736282675eSQu Wenruo * Pair with set_bit/clear_bit in clean_dirty_subvols and 5746282675eSQu Wenruo * btrfs_update_reloc_root. We need to see the updated bit before 5756282675eSQu Wenruo * trying to access reloc_root 5766282675eSQu Wenruo */ 5776282675eSQu Wenruo smp_rmb(); 5786282675eSQu Wenruo if (test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state)) 5796282675eSQu Wenruo return true; 5806282675eSQu Wenruo return false; 5816282675eSQu Wenruo } 5826282675eSQu Wenruo 5836282675eSQu Wenruo /* 5846282675eSQu Wenruo * Check if this subvolume tree has valid reloc tree. 5856282675eSQu Wenruo * 5866282675eSQu Wenruo * Reloc tree after swap is considered dead, thus not considered as valid. 5876282675eSQu Wenruo * This is enough for most callers, as they don't distinguish dead reloc root 5886282675eSQu Wenruo * from no reloc root. But should_ignore_root() below is a special case. 5896282675eSQu Wenruo */ 5906282675eSQu Wenruo static bool have_reloc_root(struct btrfs_root *root) 5916282675eSQu Wenruo { 5926282675eSQu Wenruo if (reloc_root_is_dead(root)) 5936282675eSQu Wenruo return false; 5946282675eSQu Wenruo if (!root->reloc_root) 5956282675eSQu Wenruo return false; 5966282675eSQu Wenruo return true; 5976282675eSQu Wenruo } 598f2a97a9dSDavid Sterba 5993fd0a558SYan, Zheng static int should_ignore_root(struct btrfs_root *root) 6003fd0a558SYan, Zheng { 6013fd0a558SYan, Zheng struct btrfs_root *reloc_root; 6023fd0a558SYan, Zheng 60327cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 6043fd0a558SYan, Zheng return 0; 6053fd0a558SYan, Zheng 6066282675eSQu Wenruo /* This root has been merged with its reloc tree, we can ignore it */ 6076282675eSQu Wenruo if (reloc_root_is_dead(root)) 6086282675eSQu Wenruo return 1; 6096282675eSQu Wenruo 6103fd0a558SYan, Zheng reloc_root = root->reloc_root; 6113fd0a558SYan, Zheng if (!reloc_root) 6123fd0a558SYan, Zheng return 0; 6133fd0a558SYan, Zheng 6144d4225fcSJosef Bacik if (btrfs_header_generation(reloc_root->commit_root) == 6154d4225fcSJosef Bacik root->fs_info->running_transaction->transid) 6163fd0a558SYan, Zheng return 0; 6173fd0a558SYan, Zheng /* 6183fd0a558SYan, Zheng * if there is reloc tree and it was created in previous 6193fd0a558SYan, Zheng * transaction backref lookup can find the reloc tree, 6203fd0a558SYan, Zheng * so backref node for the fs tree root is useless for 6213fd0a558SYan, Zheng * relocation. 6223fd0a558SYan, Zheng */ 6233fd0a558SYan, Zheng return 1; 6243fd0a558SYan, Zheng } 6255d4f98a2SYan Zheng /* 6265d4f98a2SYan Zheng * find reloc tree by address of tree root 6275d4f98a2SYan Zheng */ 6285d4f98a2SYan Zheng static struct btrfs_root *find_reloc_root(struct reloc_control *rc, 6295d4f98a2SYan Zheng u64 bytenr) 6305d4f98a2SYan Zheng { 6315d4f98a2SYan Zheng struct rb_node *rb_node; 6325d4f98a2SYan Zheng struct mapping_node *node; 6335d4f98a2SYan Zheng struct btrfs_root *root = NULL; 6345d4f98a2SYan Zheng 6355d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 6365d4f98a2SYan Zheng rb_node = tree_search(&rc->reloc_root_tree.rb_root, bytenr); 6375d4f98a2SYan Zheng if (rb_node) { 6385d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 6395d4f98a2SYan Zheng root = (struct btrfs_root *)node->data; 6405d4f98a2SYan Zheng } 6415d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 64200246528SJosef Bacik return btrfs_grab_root(root); 6435d4f98a2SYan Zheng } 6445d4f98a2SYan Zheng 6455d4f98a2SYan Zheng static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, 6465d4f98a2SYan Zheng u64 root_objectid) 6475d4f98a2SYan Zheng { 6485d4f98a2SYan Zheng struct btrfs_key key; 6495d4f98a2SYan Zheng 6505d4f98a2SYan Zheng key.objectid = root_objectid; 6515d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 6525d4f98a2SYan Zheng key.offset = (u64)-1; 6535d4f98a2SYan Zheng 654bc44d7c4SJosef Bacik return btrfs_get_fs_root(fs_info, &key, false); 6555d4f98a2SYan Zheng } 6565d4f98a2SYan Zheng 6575d4f98a2SYan Zheng /* 6585d4f98a2SYan Zheng * build backref tree for a given tree block. root of the backref tree 6595d4f98a2SYan Zheng * corresponds the tree block, leaves of the backref tree correspond 6605d4f98a2SYan Zheng * roots of b-trees that reference the tree block. 6615d4f98a2SYan Zheng * 6625d4f98a2SYan Zheng * the basic idea of this function is check backrefs of a given block 66301327610SNicholas D Steeves * to find upper level blocks that reference the block, and then check 66401327610SNicholas D Steeves * backrefs of these upper level blocks recursively. the recursion stop 6655d4f98a2SYan Zheng * when tree root is reached or backrefs for the block is cached. 6665d4f98a2SYan Zheng * 6675d4f98a2SYan Zheng * NOTE: if we find backrefs for a block are cached, we know backrefs 6685d4f98a2SYan Zheng * for all upper level blocks that directly/indirectly reference the 6695d4f98a2SYan Zheng * block are also cached. 6705d4f98a2SYan Zheng */ 6713fd0a558SYan, Zheng static noinline_for_stack 6723fd0a558SYan, Zheng struct backref_node *build_backref_tree(struct reloc_control *rc, 6735d4f98a2SYan Zheng struct btrfs_key *node_key, 6745d4f98a2SYan Zheng int level, u64 bytenr) 6755d4f98a2SYan Zheng { 67671f572a9SQu Wenruo struct btrfs_backref_iter *iter; 6773fd0a558SYan, Zheng struct backref_cache *cache = &rc->backref_cache; 67871f572a9SQu Wenruo /* For searching parent of TREE_BLOCK_REF */ 67971f572a9SQu Wenruo struct btrfs_path *path; 6805d4f98a2SYan Zheng struct btrfs_root *root; 6815d4f98a2SYan Zheng struct backref_node *cur; 6825d4f98a2SYan Zheng struct backref_node *upper; 6835d4f98a2SYan Zheng struct backref_node *lower; 6845d4f98a2SYan Zheng struct backref_node *node = NULL; 6855d4f98a2SYan Zheng struct backref_node *exist = NULL; 6865d4f98a2SYan Zheng struct backref_edge *edge; 6875d4f98a2SYan Zheng struct rb_node *rb_node; 688fa6ac715SQu Wenruo LIST_HEAD(list); /* Pending edge list, upper node needs to be checked */ 6893fd0a558SYan, Zheng LIST_HEAD(useless); 6903fd0a558SYan, Zheng int cowonly; 6915d4f98a2SYan Zheng int ret; 6925d4f98a2SYan Zheng int err = 0; 693b6c60c80SJosef Bacik bool need_check = true; 6945d4f98a2SYan Zheng 69571f572a9SQu Wenruo iter = btrfs_backref_iter_alloc(rc->extent_root->fs_info, GFP_NOFS); 69671f572a9SQu Wenruo if (!iter) 69771f572a9SQu Wenruo return ERR_PTR(-ENOMEM); 69871f572a9SQu Wenruo path = btrfs_alloc_path(); 69971f572a9SQu Wenruo if (!path) { 7005d4f98a2SYan Zheng err = -ENOMEM; 7015d4f98a2SYan Zheng goto out; 7025d4f98a2SYan Zheng } 7035d4f98a2SYan Zheng 7043fd0a558SYan, Zheng node = alloc_backref_node(cache); 7055d4f98a2SYan Zheng if (!node) { 7065d4f98a2SYan Zheng err = -ENOMEM; 7075d4f98a2SYan Zheng goto out; 7085d4f98a2SYan Zheng } 7095d4f98a2SYan Zheng 7105d4f98a2SYan Zheng node->bytenr = bytenr; 7115d4f98a2SYan Zheng node->level = level; 7125d4f98a2SYan Zheng node->lowest = 1; 7135d4f98a2SYan Zheng cur = node; 7145d4f98a2SYan Zheng again: 71571f572a9SQu Wenruo ret = btrfs_backref_iter_start(iter, cur->bytenr); 7165d4f98a2SYan Zheng if (ret < 0) { 7175d4f98a2SYan Zheng err = ret; 7185d4f98a2SYan Zheng goto out; 7195d4f98a2SYan Zheng } 7205d4f98a2SYan Zheng 72171f572a9SQu Wenruo /* 72271f572a9SQu Wenruo * We skip the first btrfs_tree_block_info, as we don't use the key 72371f572a9SQu Wenruo * stored in it, but fetch it from the tree block 72471f572a9SQu Wenruo */ 72571f572a9SQu Wenruo if (btrfs_backref_has_tree_block_info(iter)) { 72671f572a9SQu Wenruo ret = btrfs_backref_iter_next(iter); 72771f572a9SQu Wenruo if (ret < 0) { 72871f572a9SQu Wenruo err = ret; 72971f572a9SQu Wenruo goto out; 73071f572a9SQu Wenruo } 73171f572a9SQu Wenruo /* No extra backref? This means the tree block is corrupted */ 73271f572a9SQu Wenruo if (ret > 0) { 73371f572a9SQu Wenruo err = -EUCLEAN; 73471f572a9SQu Wenruo goto out; 73571f572a9SQu Wenruo } 73671f572a9SQu Wenruo } 7375d4f98a2SYan Zheng WARN_ON(cur->checked); 7385d4f98a2SYan Zheng if (!list_empty(&cur->upper)) { 7395d4f98a2SYan Zheng /* 74070f23fd6SJustin P. Mattock * the backref was added previously when processing 7415d4f98a2SYan Zheng * backref of type BTRFS_TREE_BLOCK_REF_KEY 7425d4f98a2SYan Zheng */ 74375bfb9afSJosef Bacik ASSERT(list_is_singular(&cur->upper)); 7445d4f98a2SYan Zheng edge = list_entry(cur->upper.next, struct backref_edge, 7455d4f98a2SYan Zheng list[LOWER]); 74675bfb9afSJosef Bacik ASSERT(list_empty(&edge->list[UPPER])); 7475d4f98a2SYan Zheng exist = edge->node[UPPER]; 7485d4f98a2SYan Zheng /* 7495d4f98a2SYan Zheng * add the upper level block to pending list if we need 7505d4f98a2SYan Zheng * check its backrefs 7515d4f98a2SYan Zheng */ 7525d4f98a2SYan Zheng if (!exist->checked) 7535d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 7545d4f98a2SYan Zheng } else { 7555d4f98a2SYan Zheng exist = NULL; 7565d4f98a2SYan Zheng } 7575d4f98a2SYan Zheng 75871f572a9SQu Wenruo for (; ret == 0; ret = btrfs_backref_iter_next(iter)) { 75971f572a9SQu Wenruo struct extent_buffer *eb; 76071f572a9SQu Wenruo struct btrfs_key key; 7613de28d57SLiu Bo int type; 76271f572a9SQu Wenruo 76371f572a9SQu Wenruo cond_resched(); 76471f572a9SQu Wenruo eb = btrfs_backref_get_eb(iter); 76571f572a9SQu Wenruo 76671f572a9SQu Wenruo key.objectid = iter->bytenr; 76771f572a9SQu Wenruo if (btrfs_backref_iter_is_inline_ref(iter)) { 76871f572a9SQu Wenruo struct btrfs_extent_inline_ref *iref; 76971f572a9SQu Wenruo 77071f572a9SQu Wenruo /* update key for inline back ref */ 77171f572a9SQu Wenruo iref = (struct btrfs_extent_inline_ref *) 77271f572a9SQu Wenruo ((unsigned long)iter->cur_ptr); 7733de28d57SLiu Bo type = btrfs_get_extent_inline_ref_type(eb, iref, 7743de28d57SLiu Bo BTRFS_REF_TYPE_BLOCK); 7753de28d57SLiu Bo if (type == BTRFS_REF_TYPE_INVALID) { 776af431dcbSSu Yue err = -EUCLEAN; 7773de28d57SLiu Bo goto out; 7783de28d57SLiu Bo } 7793de28d57SLiu Bo key.type = type; 7805d4f98a2SYan Zheng key.offset = btrfs_extent_inline_ref_offset(eb, iref); 78171f572a9SQu Wenruo } else { 78271f572a9SQu Wenruo key.type = iter->cur_key.type; 78371f572a9SQu Wenruo key.offset = iter->cur_key.offset; 7845d4f98a2SYan Zheng } 7855d4f98a2SYan Zheng 786fa6ac715SQu Wenruo /* 787fa6ac715SQu Wenruo * Parent node found and matches current inline ref, no need to 788fa6ac715SQu Wenruo * rebuild this node for this inline ref. 789fa6ac715SQu Wenruo */ 7905d4f98a2SYan Zheng if (exist && 7915d4f98a2SYan Zheng ((key.type == BTRFS_TREE_BLOCK_REF_KEY && 7925d4f98a2SYan Zheng exist->owner == key.offset) || 7935d4f98a2SYan Zheng (key.type == BTRFS_SHARED_BLOCK_REF_KEY && 7945d4f98a2SYan Zheng exist->bytenr == key.offset))) { 7955d4f98a2SYan Zheng exist = NULL; 79671f572a9SQu Wenruo continue; 7975d4f98a2SYan Zheng } 7985d4f98a2SYan Zheng 799fa6ac715SQu Wenruo /* SHARED_BLOCK_REF means key.offset is the parent bytenr */ 8005d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { 8015d4f98a2SYan Zheng if (key.objectid == key.offset) { 8025d4f98a2SYan Zheng /* 803fa6ac715SQu Wenruo * Only root blocks of reloc trees use backref 804fa6ac715SQu Wenruo * pointing to itself. 8055d4f98a2SYan Zheng */ 8065d4f98a2SYan Zheng root = find_reloc_root(rc, cur->bytenr); 80775bfb9afSJosef Bacik ASSERT(root); 8085d4f98a2SYan Zheng cur->root = root; 8095d4f98a2SYan Zheng break; 8105d4f98a2SYan Zheng } 8115d4f98a2SYan Zheng 8123fd0a558SYan, Zheng edge = alloc_backref_edge(cache); 8135d4f98a2SYan Zheng if (!edge) { 8145d4f98a2SYan Zheng err = -ENOMEM; 8155d4f98a2SYan Zheng goto out; 8165d4f98a2SYan Zheng } 8175d4f98a2SYan Zheng rb_node = tree_search(&cache->rb_root, key.offset); 8185d4f98a2SYan Zheng if (!rb_node) { 8193fd0a558SYan, Zheng upper = alloc_backref_node(cache); 8205d4f98a2SYan Zheng if (!upper) { 8213fd0a558SYan, Zheng free_backref_edge(cache, edge); 8225d4f98a2SYan Zheng err = -ENOMEM; 8235d4f98a2SYan Zheng goto out; 8245d4f98a2SYan Zheng } 8255d4f98a2SYan Zheng upper->bytenr = key.offset; 8265d4f98a2SYan Zheng upper->level = cur->level + 1; 8275d4f98a2SYan Zheng /* 8285d4f98a2SYan Zheng * backrefs for the upper level block isn't 8295d4f98a2SYan Zheng * cached, add the block to pending list 8305d4f98a2SYan Zheng */ 8315d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 8325d4f98a2SYan Zheng } else { 8335d4f98a2SYan Zheng upper = rb_entry(rb_node, struct backref_node, 8345d4f98a2SYan Zheng rb_node); 83575bfb9afSJosef Bacik ASSERT(upper->checked); 8365d4f98a2SYan Zheng INIT_LIST_HEAD(&edge->list[UPPER]); 8375d4f98a2SYan Zheng } 8383fd0a558SYan, Zheng list_add_tail(&edge->list[LOWER], &cur->upper); 8395d4f98a2SYan Zheng edge->node[LOWER] = cur; 8403fd0a558SYan, Zheng edge->node[UPPER] = upper; 8415d4f98a2SYan Zheng 84271f572a9SQu Wenruo continue; 8436d8ff4e4SDavid Sterba } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) { 844ba3c2b19SNikolay Borisov err = -EINVAL; 845ba3c2b19SNikolay Borisov btrfs_print_v0_err(rc->extent_root->fs_info); 846ba3c2b19SNikolay Borisov btrfs_handle_fs_error(rc->extent_root->fs_info, err, 847ba3c2b19SNikolay Borisov NULL); 848ba3c2b19SNikolay Borisov goto out; 8495d4f98a2SYan Zheng } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { 85071f572a9SQu Wenruo continue; 8515d4f98a2SYan Zheng } 8525d4f98a2SYan Zheng 853fa6ac715SQu Wenruo /* 854fa6ac715SQu Wenruo * key.type == BTRFS_TREE_BLOCK_REF_KEY, inline ref offset 855fa6ac715SQu Wenruo * means the root objectid. We need to search the tree to get 856fa6ac715SQu Wenruo * its parent bytenr. 857fa6ac715SQu Wenruo */ 8585d4f98a2SYan Zheng root = read_fs_root(rc->extent_root->fs_info, key.offset); 8595d4f98a2SYan Zheng if (IS_ERR(root)) { 8605d4f98a2SYan Zheng err = PTR_ERR(root); 8615d4f98a2SYan Zheng goto out; 8625d4f98a2SYan Zheng } 8635d4f98a2SYan Zheng 86427cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 8653fd0a558SYan, Zheng cur->cowonly = 1; 8663fd0a558SYan, Zheng 8675d4f98a2SYan Zheng if (btrfs_root_level(&root->root_item) == cur->level) { 8685d4f98a2SYan Zheng /* tree root */ 86975bfb9afSJosef Bacik ASSERT(btrfs_root_bytenr(&root->root_item) == 8705d4f98a2SYan Zheng cur->bytenr); 8710b530bc5SJosef Bacik if (should_ignore_root(root)) { 87200246528SJosef Bacik btrfs_put_root(root); 8733fd0a558SYan, Zheng list_add(&cur->list, &useless); 8740b530bc5SJosef Bacik } else { 8755d4f98a2SYan Zheng cur->root = root; 8760b530bc5SJosef Bacik } 8775d4f98a2SYan Zheng break; 8785d4f98a2SYan Zheng } 8795d4f98a2SYan Zheng 8805d4f98a2SYan Zheng level = cur->level + 1; 8815d4f98a2SYan Zheng 882fa6ac715SQu Wenruo /* Search the tree to find parent blocks referring the block. */ 88371f572a9SQu Wenruo path->search_commit_root = 1; 88471f572a9SQu Wenruo path->skip_locking = 1; 88571f572a9SQu Wenruo path->lowest_level = level; 88671f572a9SQu Wenruo ret = btrfs_search_slot(NULL, root, node_key, path, 0, 0); 88771f572a9SQu Wenruo path->lowest_level = 0; 8885d4f98a2SYan Zheng if (ret < 0) { 88900246528SJosef Bacik btrfs_put_root(root); 8905d4f98a2SYan Zheng err = ret; 8915d4f98a2SYan Zheng goto out; 8925d4f98a2SYan Zheng } 89371f572a9SQu Wenruo if (ret > 0 && path->slots[level] > 0) 89471f572a9SQu Wenruo path->slots[level]--; 8955d4f98a2SYan Zheng 89671f572a9SQu Wenruo eb = path->nodes[level]; 89771f572a9SQu Wenruo if (btrfs_node_blockptr(eb, path->slots[level]) != 8983561b9dbSLiu Bo cur->bytenr) { 8993561b9dbSLiu Bo btrfs_err(root->fs_info, 9003561b9dbSLiu Bo "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)", 9014fd786e6SMisono Tomohiro cur->bytenr, level - 1, 9024fd786e6SMisono Tomohiro root->root_key.objectid, 9033561b9dbSLiu Bo node_key->objectid, node_key->type, 9043561b9dbSLiu Bo node_key->offset); 90500246528SJosef Bacik btrfs_put_root(root); 9063561b9dbSLiu Bo err = -ENOENT; 9073561b9dbSLiu Bo goto out; 9083561b9dbSLiu Bo } 9095d4f98a2SYan Zheng lower = cur; 910b6c60c80SJosef Bacik need_check = true; 911fa6ac715SQu Wenruo 912fa6ac715SQu Wenruo /* Add all nodes and edges in the path */ 9135d4f98a2SYan Zheng for (; level < BTRFS_MAX_LEVEL; level++) { 91471f572a9SQu Wenruo if (!path->nodes[level]) { 91575bfb9afSJosef Bacik ASSERT(btrfs_root_bytenr(&root->root_item) == 9165d4f98a2SYan Zheng lower->bytenr); 9170b530bc5SJosef Bacik if (should_ignore_root(root)) { 91800246528SJosef Bacik btrfs_put_root(root); 9193fd0a558SYan, Zheng list_add(&lower->list, &useless); 9200b530bc5SJosef Bacik } else { 9215d4f98a2SYan Zheng lower->root = root; 9220b530bc5SJosef Bacik } 9235d4f98a2SYan Zheng break; 9245d4f98a2SYan Zheng } 9255d4f98a2SYan Zheng 9263fd0a558SYan, Zheng edge = alloc_backref_edge(cache); 9275d4f98a2SYan Zheng if (!edge) { 92800246528SJosef Bacik btrfs_put_root(root); 9295d4f98a2SYan Zheng err = -ENOMEM; 9305d4f98a2SYan Zheng goto out; 9315d4f98a2SYan Zheng } 9325d4f98a2SYan Zheng 93371f572a9SQu Wenruo eb = path->nodes[level]; 9345d4f98a2SYan Zheng rb_node = tree_search(&cache->rb_root, eb->start); 9355d4f98a2SYan Zheng if (!rb_node) { 9363fd0a558SYan, Zheng upper = alloc_backref_node(cache); 9375d4f98a2SYan Zheng if (!upper) { 93800246528SJosef Bacik btrfs_put_root(root); 9393fd0a558SYan, Zheng free_backref_edge(cache, edge); 9405d4f98a2SYan Zheng err = -ENOMEM; 9415d4f98a2SYan Zheng goto out; 9425d4f98a2SYan Zheng } 9435d4f98a2SYan Zheng upper->bytenr = eb->start; 9445d4f98a2SYan Zheng upper->owner = btrfs_header_owner(eb); 9455d4f98a2SYan Zheng upper->level = lower->level + 1; 94627cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, 94727cdeb70SMiao Xie &root->state)) 9483fd0a558SYan, Zheng upper->cowonly = 1; 9495d4f98a2SYan Zheng 9505d4f98a2SYan Zheng /* 9515d4f98a2SYan Zheng * if we know the block isn't shared 9525d4f98a2SYan Zheng * we can void checking its backrefs. 9535d4f98a2SYan Zheng */ 9545d4f98a2SYan Zheng if (btrfs_block_can_be_shared(root, eb)) 9555d4f98a2SYan Zheng upper->checked = 0; 9565d4f98a2SYan Zheng else 9575d4f98a2SYan Zheng upper->checked = 1; 9585d4f98a2SYan Zheng 9595d4f98a2SYan Zheng /* 9605d4f98a2SYan Zheng * add the block to pending list if we 961b6c60c80SJosef Bacik * need check its backrefs, we only do this once 962b6c60c80SJosef Bacik * while walking up a tree as we will catch 963b6c60c80SJosef Bacik * anything else later on. 9645d4f98a2SYan Zheng */ 965b6c60c80SJosef Bacik if (!upper->checked && need_check) { 966b6c60c80SJosef Bacik need_check = false; 9675d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], 9685d4f98a2SYan Zheng &list); 969bbe90514SJosef Bacik } else { 970bbe90514SJosef Bacik if (upper->checked) 971bbe90514SJosef Bacik need_check = true; 9725d4f98a2SYan Zheng INIT_LIST_HEAD(&edge->list[UPPER]); 973bbe90514SJosef Bacik } 9745d4f98a2SYan Zheng } else { 9755d4f98a2SYan Zheng upper = rb_entry(rb_node, struct backref_node, 9765d4f98a2SYan Zheng rb_node); 97775bfb9afSJosef Bacik ASSERT(upper->checked); 9785d4f98a2SYan Zheng INIT_LIST_HEAD(&edge->list[UPPER]); 9793fd0a558SYan, Zheng if (!upper->owner) 9803fd0a558SYan, Zheng upper->owner = btrfs_header_owner(eb); 9815d4f98a2SYan Zheng } 9825d4f98a2SYan Zheng list_add_tail(&edge->list[LOWER], &lower->upper); 9835d4f98a2SYan Zheng edge->node[LOWER] = lower; 9843fd0a558SYan, Zheng edge->node[UPPER] = upper; 9855d4f98a2SYan Zheng 9860b530bc5SJosef Bacik if (rb_node) { 98700246528SJosef Bacik btrfs_put_root(root); 9885d4f98a2SYan Zheng break; 9890b530bc5SJosef Bacik } 9905d4f98a2SYan Zheng lower = upper; 9915d4f98a2SYan Zheng upper = NULL; 9925d4f98a2SYan Zheng } 99371f572a9SQu Wenruo btrfs_release_path(path); 9945d4f98a2SYan Zheng } 99571f572a9SQu Wenruo if (ret < 0) { 99671f572a9SQu Wenruo err = ret; 99771f572a9SQu Wenruo goto out; 9985d4f98a2SYan Zheng } 99971f572a9SQu Wenruo ret = 0; 100071f572a9SQu Wenruo btrfs_backref_iter_release(iter); 10015d4f98a2SYan Zheng 10025d4f98a2SYan Zheng cur->checked = 1; 10035d4f98a2SYan Zheng WARN_ON(exist); 10045d4f98a2SYan Zheng 10055d4f98a2SYan Zheng /* the pending list isn't empty, take the first block to process */ 10065d4f98a2SYan Zheng if (!list_empty(&list)) { 10075d4f98a2SYan Zheng edge = list_entry(list.next, struct backref_edge, list[UPPER]); 10085d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 10095d4f98a2SYan Zheng cur = edge->node[UPPER]; 10105d4f98a2SYan Zheng goto again; 10115d4f98a2SYan Zheng } 10125d4f98a2SYan Zheng 10135d4f98a2SYan Zheng /* 10145d4f98a2SYan Zheng * everything goes well, connect backref nodes and insert backref nodes 10155d4f98a2SYan Zheng * into the cache. 10165d4f98a2SYan Zheng */ 101775bfb9afSJosef Bacik ASSERT(node->checked); 10183fd0a558SYan, Zheng cowonly = node->cowonly; 10193fd0a558SYan, Zheng if (!cowonly) { 10203fd0a558SYan, Zheng rb_node = tree_insert(&cache->rb_root, node->bytenr, 10213fd0a558SYan, Zheng &node->rb_node); 102243c04fb1SJeff Mahoney if (rb_node) 102343c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, node->bytenr); 10243fd0a558SYan, Zheng list_add_tail(&node->lower, &cache->leaves); 10253fd0a558SYan, Zheng } 10265d4f98a2SYan Zheng 10275d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) 10285d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 10295d4f98a2SYan Zheng 10305d4f98a2SYan Zheng while (!list_empty(&list)) { 10315d4f98a2SYan Zheng edge = list_entry(list.next, struct backref_edge, list[UPPER]); 10325d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 10335d4f98a2SYan Zheng upper = edge->node[UPPER]; 10343fd0a558SYan, Zheng if (upper->detached) { 10353fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 10363fd0a558SYan, Zheng lower = edge->node[LOWER]; 10373fd0a558SYan, Zheng free_backref_edge(cache, edge); 10383fd0a558SYan, Zheng if (list_empty(&lower->upper)) 10393fd0a558SYan, Zheng list_add(&lower->list, &useless); 10403fd0a558SYan, Zheng continue; 10413fd0a558SYan, Zheng } 10425d4f98a2SYan Zheng 10435d4f98a2SYan Zheng if (!RB_EMPTY_NODE(&upper->rb_node)) { 10445d4f98a2SYan Zheng if (upper->lowest) { 10455d4f98a2SYan Zheng list_del_init(&upper->lower); 10465d4f98a2SYan Zheng upper->lowest = 0; 10475d4f98a2SYan Zheng } 10485d4f98a2SYan Zheng 10495d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &upper->lower); 10505d4f98a2SYan Zheng continue; 10515d4f98a2SYan Zheng } 10525d4f98a2SYan Zheng 105375bfb9afSJosef Bacik if (!upper->checked) { 105475bfb9afSJosef Bacik /* 105575bfb9afSJosef Bacik * Still want to blow up for developers since this is a 105675bfb9afSJosef Bacik * logic bug. 105775bfb9afSJosef Bacik */ 105875bfb9afSJosef Bacik ASSERT(0); 105975bfb9afSJosef Bacik err = -EINVAL; 106075bfb9afSJosef Bacik goto out; 106175bfb9afSJosef Bacik } 106275bfb9afSJosef Bacik if (cowonly != upper->cowonly) { 106375bfb9afSJosef Bacik ASSERT(0); 106475bfb9afSJosef Bacik err = -EINVAL; 106575bfb9afSJosef Bacik goto out; 106675bfb9afSJosef Bacik } 106775bfb9afSJosef Bacik 10683fd0a558SYan, Zheng if (!cowonly) { 10695d4f98a2SYan Zheng rb_node = tree_insert(&cache->rb_root, upper->bytenr, 10705d4f98a2SYan Zheng &upper->rb_node); 107143c04fb1SJeff Mahoney if (rb_node) 107243c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, 107343c04fb1SJeff Mahoney upper->bytenr); 10743fd0a558SYan, Zheng } 10755d4f98a2SYan Zheng 10765d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &upper->lower); 10775d4f98a2SYan Zheng 10785d4f98a2SYan Zheng list_for_each_entry(edge, &upper->upper, list[LOWER]) 10795d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 10805d4f98a2SYan Zheng } 10813fd0a558SYan, Zheng /* 10823fd0a558SYan, Zheng * process useless backref nodes. backref nodes for tree leaves 10833fd0a558SYan, Zheng * are deleted from the cache. backref nodes for upper level 10843fd0a558SYan, Zheng * tree blocks are left in the cache to avoid unnecessary backref 10853fd0a558SYan, Zheng * lookup. 10863fd0a558SYan, Zheng */ 10873fd0a558SYan, Zheng while (!list_empty(&useless)) { 10883fd0a558SYan, Zheng upper = list_entry(useless.next, struct backref_node, list); 10893fd0a558SYan, Zheng list_del_init(&upper->list); 109075bfb9afSJosef Bacik ASSERT(list_empty(&upper->upper)); 10913fd0a558SYan, Zheng if (upper == node) 10923fd0a558SYan, Zheng node = NULL; 10933fd0a558SYan, Zheng if (upper->lowest) { 10943fd0a558SYan, Zheng list_del_init(&upper->lower); 10953fd0a558SYan, Zheng upper->lowest = 0; 10963fd0a558SYan, Zheng } 10973fd0a558SYan, Zheng while (!list_empty(&upper->lower)) { 10983fd0a558SYan, Zheng edge = list_entry(upper->lower.next, 10993fd0a558SYan, Zheng struct backref_edge, list[UPPER]); 11003fd0a558SYan, Zheng list_del(&edge->list[UPPER]); 11013fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 11023fd0a558SYan, Zheng lower = edge->node[LOWER]; 11033fd0a558SYan, Zheng free_backref_edge(cache, edge); 11043fd0a558SYan, Zheng 11053fd0a558SYan, Zheng if (list_empty(&lower->upper)) 11063fd0a558SYan, Zheng list_add(&lower->list, &useless); 11073fd0a558SYan, Zheng } 11083fd0a558SYan, Zheng __mark_block_processed(rc, upper); 11093fd0a558SYan, Zheng if (upper->level > 0) { 11103fd0a558SYan, Zheng list_add(&upper->list, &cache->detached); 11113fd0a558SYan, Zheng upper->detached = 1; 11123fd0a558SYan, Zheng } else { 11133fd0a558SYan, Zheng rb_erase(&upper->rb_node, &cache->rb_root); 11143fd0a558SYan, Zheng free_backref_node(cache, upper); 11153fd0a558SYan, Zheng } 11163fd0a558SYan, Zheng } 11175d4f98a2SYan Zheng out: 111871f572a9SQu Wenruo btrfs_backref_iter_free(iter); 111971f572a9SQu Wenruo btrfs_free_path(path); 11205d4f98a2SYan Zheng if (err) { 11213fd0a558SYan, Zheng while (!list_empty(&useless)) { 11223fd0a558SYan, Zheng lower = list_entry(useless.next, 112375bfb9afSJosef Bacik struct backref_node, list); 112475bfb9afSJosef Bacik list_del_init(&lower->list); 11253fd0a558SYan, Zheng } 112675bfb9afSJosef Bacik while (!list_empty(&list)) { 112775bfb9afSJosef Bacik edge = list_first_entry(&list, struct backref_edge, 112875bfb9afSJosef Bacik list[UPPER]); 112975bfb9afSJosef Bacik list_del(&edge->list[UPPER]); 11303fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 113175bfb9afSJosef Bacik lower = edge->node[LOWER]; 11325d4f98a2SYan Zheng upper = edge->node[UPPER]; 11333fd0a558SYan, Zheng free_backref_edge(cache, edge); 113475bfb9afSJosef Bacik 113575bfb9afSJosef Bacik /* 113675bfb9afSJosef Bacik * Lower is no longer linked to any upper backref nodes 113775bfb9afSJosef Bacik * and isn't in the cache, we can free it ourselves. 113875bfb9afSJosef Bacik */ 113975bfb9afSJosef Bacik if (list_empty(&lower->upper) && 114075bfb9afSJosef Bacik RB_EMPTY_NODE(&lower->rb_node)) 114175bfb9afSJosef Bacik list_add(&lower->list, &useless); 114275bfb9afSJosef Bacik 114375bfb9afSJosef Bacik if (!RB_EMPTY_NODE(&upper->rb_node)) 114475bfb9afSJosef Bacik continue; 114575bfb9afSJosef Bacik 114601327610SNicholas D Steeves /* Add this guy's upper edges to the list to process */ 114775bfb9afSJosef Bacik list_for_each_entry(edge, &upper->upper, list[LOWER]) 114875bfb9afSJosef Bacik list_add_tail(&edge->list[UPPER], &list); 114975bfb9afSJosef Bacik if (list_empty(&upper->upper)) 115075bfb9afSJosef Bacik list_add(&upper->list, &useless); 115175bfb9afSJosef Bacik } 115275bfb9afSJosef Bacik 115375bfb9afSJosef Bacik while (!list_empty(&useless)) { 115475bfb9afSJosef Bacik lower = list_entry(useless.next, 115575bfb9afSJosef Bacik struct backref_node, list); 115675bfb9afSJosef Bacik list_del_init(&lower->list); 11570fd8c3daSLiu Bo if (lower == node) 11580fd8c3daSLiu Bo node = NULL; 115975bfb9afSJosef Bacik free_backref_node(cache, lower); 11605d4f98a2SYan Zheng } 11610fd8c3daSLiu Bo 11628e19c973SJosef Bacik remove_backref_node(cache, node); 11635d4f98a2SYan Zheng return ERR_PTR(err); 11645d4f98a2SYan Zheng } 116575bfb9afSJosef Bacik ASSERT(!node || !node->detached); 11665d4f98a2SYan Zheng return node; 11675d4f98a2SYan Zheng } 11685d4f98a2SYan Zheng 11695d4f98a2SYan Zheng /* 11703fd0a558SYan, Zheng * helper to add backref node for the newly created snapshot. 11713fd0a558SYan, Zheng * the backref node is created by cloning backref node that 11723fd0a558SYan, Zheng * corresponds to root of source tree 11733fd0a558SYan, Zheng */ 11743fd0a558SYan, Zheng static int clone_backref_node(struct btrfs_trans_handle *trans, 11753fd0a558SYan, Zheng struct reloc_control *rc, 11763fd0a558SYan, Zheng struct btrfs_root *src, 11773fd0a558SYan, Zheng struct btrfs_root *dest) 11783fd0a558SYan, Zheng { 11793fd0a558SYan, Zheng struct btrfs_root *reloc_root = src->reloc_root; 11803fd0a558SYan, Zheng struct backref_cache *cache = &rc->backref_cache; 11813fd0a558SYan, Zheng struct backref_node *node = NULL; 11823fd0a558SYan, Zheng struct backref_node *new_node; 11833fd0a558SYan, Zheng struct backref_edge *edge; 11843fd0a558SYan, Zheng struct backref_edge *new_edge; 11853fd0a558SYan, Zheng struct rb_node *rb_node; 11863fd0a558SYan, Zheng 11873fd0a558SYan, Zheng if (cache->last_trans > 0) 11883fd0a558SYan, Zheng update_backref_cache(trans, cache); 11893fd0a558SYan, Zheng 11903fd0a558SYan, Zheng rb_node = tree_search(&cache->rb_root, src->commit_root->start); 11913fd0a558SYan, Zheng if (rb_node) { 11923fd0a558SYan, Zheng node = rb_entry(rb_node, struct backref_node, rb_node); 11933fd0a558SYan, Zheng if (node->detached) 11943fd0a558SYan, Zheng node = NULL; 11953fd0a558SYan, Zheng else 11963fd0a558SYan, Zheng BUG_ON(node->new_bytenr != reloc_root->node->start); 11973fd0a558SYan, Zheng } 11983fd0a558SYan, Zheng 11993fd0a558SYan, Zheng if (!node) { 12003fd0a558SYan, Zheng rb_node = tree_search(&cache->rb_root, 12013fd0a558SYan, Zheng reloc_root->commit_root->start); 12023fd0a558SYan, Zheng if (rb_node) { 12033fd0a558SYan, Zheng node = rb_entry(rb_node, struct backref_node, 12043fd0a558SYan, Zheng rb_node); 12053fd0a558SYan, Zheng BUG_ON(node->detached); 12063fd0a558SYan, Zheng } 12073fd0a558SYan, Zheng } 12083fd0a558SYan, Zheng 12093fd0a558SYan, Zheng if (!node) 12103fd0a558SYan, Zheng return 0; 12113fd0a558SYan, Zheng 12123fd0a558SYan, Zheng new_node = alloc_backref_node(cache); 12133fd0a558SYan, Zheng if (!new_node) 12143fd0a558SYan, Zheng return -ENOMEM; 12153fd0a558SYan, Zheng 12163fd0a558SYan, Zheng new_node->bytenr = dest->node->start; 12173fd0a558SYan, Zheng new_node->level = node->level; 12183fd0a558SYan, Zheng new_node->lowest = node->lowest; 12196848ad64SYan, Zheng new_node->checked = 1; 122000246528SJosef Bacik new_node->root = btrfs_grab_root(dest); 12210b530bc5SJosef Bacik ASSERT(new_node->root); 12223fd0a558SYan, Zheng 12233fd0a558SYan, Zheng if (!node->lowest) { 12243fd0a558SYan, Zheng list_for_each_entry(edge, &node->lower, list[UPPER]) { 12253fd0a558SYan, Zheng new_edge = alloc_backref_edge(cache); 12263fd0a558SYan, Zheng if (!new_edge) 12273fd0a558SYan, Zheng goto fail; 12283fd0a558SYan, Zheng 12293fd0a558SYan, Zheng new_edge->node[UPPER] = new_node; 12303fd0a558SYan, Zheng new_edge->node[LOWER] = edge->node[LOWER]; 12313fd0a558SYan, Zheng list_add_tail(&new_edge->list[UPPER], 12323fd0a558SYan, Zheng &new_node->lower); 12333fd0a558SYan, Zheng } 123476b9e23dSMiao Xie } else { 123576b9e23dSMiao Xie list_add_tail(&new_node->lower, &cache->leaves); 12363fd0a558SYan, Zheng } 12373fd0a558SYan, Zheng 12383fd0a558SYan, Zheng rb_node = tree_insert(&cache->rb_root, new_node->bytenr, 12393fd0a558SYan, Zheng &new_node->rb_node); 124043c04fb1SJeff Mahoney if (rb_node) 124143c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, new_node->bytenr); 12423fd0a558SYan, Zheng 12433fd0a558SYan, Zheng if (!new_node->lowest) { 12443fd0a558SYan, Zheng list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) { 12453fd0a558SYan, Zheng list_add_tail(&new_edge->list[LOWER], 12463fd0a558SYan, Zheng &new_edge->node[LOWER]->upper); 12473fd0a558SYan, Zheng } 12483fd0a558SYan, Zheng } 12493fd0a558SYan, Zheng return 0; 12503fd0a558SYan, Zheng fail: 12513fd0a558SYan, Zheng while (!list_empty(&new_node->lower)) { 12523fd0a558SYan, Zheng new_edge = list_entry(new_node->lower.next, 12533fd0a558SYan, Zheng struct backref_edge, list[UPPER]); 12543fd0a558SYan, Zheng list_del(&new_edge->list[UPPER]); 12553fd0a558SYan, Zheng free_backref_edge(cache, new_edge); 12563fd0a558SYan, Zheng } 12573fd0a558SYan, Zheng free_backref_node(cache, new_node); 12583fd0a558SYan, Zheng return -ENOMEM; 12593fd0a558SYan, Zheng } 12603fd0a558SYan, Zheng 12613fd0a558SYan, Zheng /* 12625d4f98a2SYan Zheng * helper to add 'address of tree root -> reloc tree' mapping 12635d4f98a2SYan Zheng */ 1264ffd7b339SJeff Mahoney static int __must_check __add_reloc_root(struct btrfs_root *root) 12655d4f98a2SYan Zheng { 12660b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12675d4f98a2SYan Zheng struct rb_node *rb_node; 12685d4f98a2SYan Zheng struct mapping_node *node; 12690b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 12705d4f98a2SYan Zheng 12715d4f98a2SYan Zheng node = kmalloc(sizeof(*node), GFP_NOFS); 1272ffd7b339SJeff Mahoney if (!node) 1273ffd7b339SJeff Mahoney return -ENOMEM; 12745d4f98a2SYan Zheng 1275ea287ab1SJosef Bacik node->bytenr = root->commit_root->start; 12765d4f98a2SYan Zheng node->data = root; 12775d4f98a2SYan Zheng 12785d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 12795d4f98a2SYan Zheng rb_node = tree_insert(&rc->reloc_root_tree.rb_root, 12805d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12815d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 1282ffd7b339SJeff Mahoney if (rb_node) { 12830b246afaSJeff Mahoney btrfs_panic(fs_info, -EEXIST, 12845d163e0eSJeff Mahoney "Duplicate root found for start=%llu while inserting into relocation tree", 12855d163e0eSJeff Mahoney node->bytenr); 1286ffd7b339SJeff Mahoney } 12875d4f98a2SYan Zheng 12885d4f98a2SYan Zheng list_add_tail(&root->root_list, &rc->reloc_roots); 12895d4f98a2SYan Zheng return 0; 12905d4f98a2SYan Zheng } 12915d4f98a2SYan Zheng 12925d4f98a2SYan Zheng /* 1293c974c464SWang Shilong * helper to delete the 'address of tree root -> reloc tree' 12945d4f98a2SYan Zheng * mapping 12955d4f98a2SYan Zheng */ 1296c974c464SWang Shilong static void __del_reloc_root(struct btrfs_root *root) 12975d4f98a2SYan Zheng { 12980b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12995d4f98a2SYan Zheng struct rb_node *rb_node; 13005d4f98a2SYan Zheng struct mapping_node *node = NULL; 13010b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1302f44deb74SJosef Bacik bool put_ref = false; 13035d4f98a2SYan Zheng 130465c6e82bSQu Wenruo if (rc && root->node) { 13055d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 13065d4f98a2SYan Zheng rb_node = tree_search(&rc->reloc_root_tree.rb_root, 1307ea287ab1SJosef Bacik root->commit_root->start); 1308c974c464SWang Shilong if (rb_node) { 1309c974c464SWang Shilong node = rb_entry(rb_node, struct mapping_node, rb_node); 1310c974c464SWang Shilong rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 1311ea287ab1SJosef Bacik RB_CLEAR_NODE(&node->rb_node); 1312c974c464SWang Shilong } 1313c974c464SWang Shilong spin_unlock(&rc->reloc_root_tree.lock); 1314c974c464SWang Shilong if (!node) 1315c974c464SWang Shilong return; 1316c974c464SWang Shilong BUG_ON((struct btrfs_root *)node->data != root); 1317389305b2SQu Wenruo } 1318c974c464SWang Shilong 1319f44deb74SJosef Bacik /* 1320f44deb74SJosef Bacik * We only put the reloc root here if it's on the list. There's a lot 1321f44deb74SJosef Bacik * of places where the pattern is to splice the rc->reloc_roots, process 1322f44deb74SJosef Bacik * the reloc roots, and then add the reloc root back onto 1323f44deb74SJosef Bacik * rc->reloc_roots. If we call __del_reloc_root while it's off of the 1324f44deb74SJosef Bacik * list we don't want the reference being dropped, because the guy 1325f44deb74SJosef Bacik * messing with the list is in charge of the reference. 1326f44deb74SJosef Bacik */ 13270b246afaSJeff Mahoney spin_lock(&fs_info->trans_lock); 1328f44deb74SJosef Bacik if (!list_empty(&root->root_list)) { 1329f44deb74SJosef Bacik put_ref = true; 1330c974c464SWang Shilong list_del_init(&root->root_list); 1331f44deb74SJosef Bacik } 13320b246afaSJeff Mahoney spin_unlock(&fs_info->trans_lock); 1333f44deb74SJosef Bacik if (put_ref) 1334f44deb74SJosef Bacik btrfs_put_root(root); 1335c974c464SWang Shilong kfree(node); 1336c974c464SWang Shilong } 1337c974c464SWang Shilong 1338c974c464SWang Shilong /* 1339c974c464SWang Shilong * helper to update the 'address of tree root -> reloc tree' 1340c974c464SWang Shilong * mapping 1341c974c464SWang Shilong */ 1342ea287ab1SJosef Bacik static int __update_reloc_root(struct btrfs_root *root) 1343c974c464SWang Shilong { 13440b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 1345c974c464SWang Shilong struct rb_node *rb_node; 1346c974c464SWang Shilong struct mapping_node *node = NULL; 13470b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1348c974c464SWang Shilong 1349c974c464SWang Shilong spin_lock(&rc->reloc_root_tree.lock); 1350c974c464SWang Shilong rb_node = tree_search(&rc->reloc_root_tree.rb_root, 1351ea287ab1SJosef Bacik root->commit_root->start); 13525d4f98a2SYan Zheng if (rb_node) { 13535d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 13545d4f98a2SYan Zheng rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 13555d4f98a2SYan Zheng } 13565d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 13575d4f98a2SYan Zheng 13588f71f3e0SLiu Bo if (!node) 13598f71f3e0SLiu Bo return 0; 13605d4f98a2SYan Zheng BUG_ON((struct btrfs_root *)node->data != root); 13615d4f98a2SYan Zheng 13625d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1363ea287ab1SJosef Bacik node->bytenr = root->node->start; 13645d4f98a2SYan Zheng rb_node = tree_insert(&rc->reloc_root_tree.rb_root, 13655d4f98a2SYan Zheng node->bytenr, &node->rb_node); 13665d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 136743c04fb1SJeff Mahoney if (rb_node) 136843c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, node->bytenr); 13695d4f98a2SYan Zheng return 0; 13705d4f98a2SYan Zheng } 13715d4f98a2SYan Zheng 13723fd0a558SYan, Zheng static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, 13733fd0a558SYan, Zheng struct btrfs_root *root, u64 objectid) 13745d4f98a2SYan Zheng { 13750b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 13765d4f98a2SYan Zheng struct btrfs_root *reloc_root; 13775d4f98a2SYan Zheng struct extent_buffer *eb; 13785d4f98a2SYan Zheng struct btrfs_root_item *root_item; 13795d4f98a2SYan Zheng struct btrfs_key root_key; 13805d4f98a2SYan Zheng int ret; 13815d4f98a2SYan Zheng 13825d4f98a2SYan Zheng root_item = kmalloc(sizeof(*root_item), GFP_NOFS); 13835d4f98a2SYan Zheng BUG_ON(!root_item); 13845d4f98a2SYan Zheng 13855d4f98a2SYan Zheng root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; 13865d4f98a2SYan Zheng root_key.type = BTRFS_ROOT_ITEM_KEY; 13873fd0a558SYan, Zheng root_key.offset = objectid; 13885d4f98a2SYan Zheng 13893fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 1390054570a1SFilipe Manana u64 commit_root_gen; 1391054570a1SFilipe Manana 13923fd0a558SYan, Zheng /* called by btrfs_init_reloc_root */ 13935d4f98a2SYan Zheng ret = btrfs_copy_root(trans, root, root->commit_root, &eb, 13945d4f98a2SYan Zheng BTRFS_TREE_RELOC_OBJECTID); 13955d4f98a2SYan Zheng BUG_ON(ret); 1396054570a1SFilipe Manana /* 1397054570a1SFilipe Manana * Set the last_snapshot field to the generation of the commit 1398054570a1SFilipe Manana * root - like this ctree.c:btrfs_block_can_be_shared() behaves 1399054570a1SFilipe Manana * correctly (returns true) when the relocation root is created 1400054570a1SFilipe Manana * either inside the critical section of a transaction commit 1401054570a1SFilipe Manana * (through transaction.c:qgroup_account_snapshot()) and when 1402054570a1SFilipe Manana * it's created before the transaction commit is started. 1403054570a1SFilipe Manana */ 1404054570a1SFilipe Manana commit_root_gen = btrfs_header_generation(root->commit_root); 1405054570a1SFilipe Manana btrfs_set_root_last_snapshot(&root->root_item, commit_root_gen); 14063fd0a558SYan, Zheng } else { 14073fd0a558SYan, Zheng /* 14083fd0a558SYan, Zheng * called by btrfs_reloc_post_snapshot_hook. 14093fd0a558SYan, Zheng * the source tree is a reloc tree, all tree blocks 14103fd0a558SYan, Zheng * modified after it was created have RELOC flag 14113fd0a558SYan, Zheng * set in their headers. so it's OK to not update 14123fd0a558SYan, Zheng * the 'last_snapshot'. 14133fd0a558SYan, Zheng */ 14143fd0a558SYan, Zheng ret = btrfs_copy_root(trans, root, root->node, &eb, 14153fd0a558SYan, Zheng BTRFS_TREE_RELOC_OBJECTID); 14163fd0a558SYan, Zheng BUG_ON(ret); 14173fd0a558SYan, Zheng } 14183fd0a558SYan, Zheng 14195d4f98a2SYan Zheng memcpy(root_item, &root->root_item, sizeof(*root_item)); 14205d4f98a2SYan Zheng btrfs_set_root_bytenr(root_item, eb->start); 14215d4f98a2SYan Zheng btrfs_set_root_level(root_item, btrfs_header_level(eb)); 14225d4f98a2SYan Zheng btrfs_set_root_generation(root_item, trans->transid); 14233fd0a558SYan, Zheng 14243fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 14253fd0a558SYan, Zheng btrfs_set_root_refs(root_item, 0); 14263fd0a558SYan, Zheng memset(&root_item->drop_progress, 0, 14273fd0a558SYan, Zheng sizeof(struct btrfs_disk_key)); 14285d4f98a2SYan Zheng root_item->drop_level = 0; 14293fd0a558SYan, Zheng } 14305d4f98a2SYan Zheng 14315d4f98a2SYan Zheng btrfs_tree_unlock(eb); 14325d4f98a2SYan Zheng free_extent_buffer(eb); 14335d4f98a2SYan Zheng 14340b246afaSJeff Mahoney ret = btrfs_insert_root(trans, fs_info->tree_root, 14355d4f98a2SYan Zheng &root_key, root_item); 14365d4f98a2SYan Zheng BUG_ON(ret); 14375d4f98a2SYan Zheng kfree(root_item); 14385d4f98a2SYan Zheng 14393dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(fs_info->tree_root, &root_key); 14405d4f98a2SYan Zheng BUG_ON(IS_ERR(reloc_root)); 14413dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 14425d4f98a2SYan Zheng reloc_root->last_trans = trans->transid; 14433fd0a558SYan, Zheng return reloc_root; 14443fd0a558SYan, Zheng } 14453fd0a558SYan, Zheng 14463fd0a558SYan, Zheng /* 14473fd0a558SYan, Zheng * create reloc tree for a given fs tree. reloc tree is just a 14483fd0a558SYan, Zheng * snapshot of the fs tree with special root objectid. 1449f44deb74SJosef Bacik * 1450f44deb74SJosef Bacik * The reloc_root comes out of here with two references, one for 1451f44deb74SJosef Bacik * root->reloc_root, and another for being on the rc->reloc_roots list. 14523fd0a558SYan, Zheng */ 14533fd0a558SYan, Zheng int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, 14543fd0a558SYan, Zheng struct btrfs_root *root) 14553fd0a558SYan, Zheng { 14560b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 14573fd0a558SYan, Zheng struct btrfs_root *reloc_root; 14580b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 145920dd2cbfSMiao Xie struct btrfs_block_rsv *rsv; 14603fd0a558SYan, Zheng int clear_rsv = 0; 1461ffd7b339SJeff Mahoney int ret; 14623fd0a558SYan, Zheng 1463aec7db3bSJosef Bacik if (!rc) 14642abc726aSJosef Bacik return 0; 14652abc726aSJosef Bacik 14661fac4a54SQu Wenruo /* 14671fac4a54SQu Wenruo * The subvolume has reloc tree but the swap is finished, no need to 14681fac4a54SQu Wenruo * create/update the dead reloc tree 14691fac4a54SQu Wenruo */ 14706282675eSQu Wenruo if (reloc_root_is_dead(root)) 14711fac4a54SQu Wenruo return 0; 14721fac4a54SQu Wenruo 1473aec7db3bSJosef Bacik /* 1474aec7db3bSJosef Bacik * This is subtle but important. We do not do 1475aec7db3bSJosef Bacik * record_root_in_transaction for reloc roots, instead we record their 1476aec7db3bSJosef Bacik * corresponding fs root, and then here we update the last trans for the 1477aec7db3bSJosef Bacik * reloc root. This means that we have to do this for the entire life 1478aec7db3bSJosef Bacik * of the reloc root, regardless of which stage of the relocation we are 1479aec7db3bSJosef Bacik * in. 1480aec7db3bSJosef Bacik */ 14813fd0a558SYan, Zheng if (root->reloc_root) { 14823fd0a558SYan, Zheng reloc_root = root->reloc_root; 14833fd0a558SYan, Zheng reloc_root->last_trans = trans->transid; 14843fd0a558SYan, Zheng return 0; 14853fd0a558SYan, Zheng } 14863fd0a558SYan, Zheng 1487aec7db3bSJosef Bacik /* 1488aec7db3bSJosef Bacik * We are merging reloc roots, we do not need new reloc trees. Also 1489aec7db3bSJosef Bacik * reloc trees never need their own reloc tree. 1490aec7db3bSJosef Bacik */ 1491aec7db3bSJosef Bacik if (!rc->create_reloc_tree || 1492aec7db3bSJosef Bacik root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 1493aec7db3bSJosef Bacik return 0; 1494aec7db3bSJosef Bacik 149520dd2cbfSMiao Xie if (!trans->reloc_reserved) { 149620dd2cbfSMiao Xie rsv = trans->block_rsv; 14973fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 14983fd0a558SYan, Zheng clear_rsv = 1; 14993fd0a558SYan, Zheng } 15003fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root, root->root_key.objectid); 15013fd0a558SYan, Zheng if (clear_rsv) 150220dd2cbfSMiao Xie trans->block_rsv = rsv; 15035d4f98a2SYan Zheng 1504ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 1505ffd7b339SJeff Mahoney BUG_ON(ret < 0); 1506f44deb74SJosef Bacik root->reloc_root = btrfs_grab_root(reloc_root); 15075d4f98a2SYan Zheng return 0; 15085d4f98a2SYan Zheng } 15095d4f98a2SYan Zheng 15105d4f98a2SYan Zheng /* 15115d4f98a2SYan Zheng * update root item of reloc tree 15125d4f98a2SYan Zheng */ 15135d4f98a2SYan Zheng int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, 15145d4f98a2SYan Zheng struct btrfs_root *root) 15155d4f98a2SYan Zheng { 15160b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 15175d4f98a2SYan Zheng struct btrfs_root *reloc_root; 15185d4f98a2SYan Zheng struct btrfs_root_item *root_item; 15195d4f98a2SYan Zheng int ret; 15205d4f98a2SYan Zheng 15216282675eSQu Wenruo if (!have_reloc_root(root)) 15227585717fSChris Mason goto out; 15235d4f98a2SYan Zheng 15245d4f98a2SYan Zheng reloc_root = root->reloc_root; 15255d4f98a2SYan Zheng root_item = &reloc_root->root_item; 15265d4f98a2SYan Zheng 1527f44deb74SJosef Bacik /* 1528f44deb74SJosef Bacik * We are probably ok here, but __del_reloc_root() will drop its ref of 1529f44deb74SJosef Bacik * the root. We have the ref for root->reloc_root, but just in case 1530f44deb74SJosef Bacik * hold it while we update the reloc root. 1531f44deb74SJosef Bacik */ 1532f44deb74SJosef Bacik btrfs_grab_root(reloc_root); 1533f44deb74SJosef Bacik 1534d2311e69SQu Wenruo /* root->reloc_root will stay until current relocation finished */ 15350b246afaSJeff Mahoney if (fs_info->reloc_ctl->merge_reloc_tree && 15363fd0a558SYan, Zheng btrfs_root_refs(root_item) == 0) { 1537d2311e69SQu Wenruo set_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 15386282675eSQu Wenruo /* 15396282675eSQu Wenruo * Mark the tree as dead before we change reloc_root so 15406282675eSQu Wenruo * have_reloc_root will not touch it from now on. 15416282675eSQu Wenruo */ 15426282675eSQu Wenruo smp_wmb(); 1543c974c464SWang Shilong __del_reloc_root(reloc_root); 15445d4f98a2SYan Zheng } 15455d4f98a2SYan Zheng 15465d4f98a2SYan Zheng if (reloc_root->commit_root != reloc_root->node) { 1547ea287ab1SJosef Bacik __update_reloc_root(reloc_root); 15485d4f98a2SYan Zheng btrfs_set_root_node(root_item, reloc_root->node); 15495d4f98a2SYan Zheng free_extent_buffer(reloc_root->commit_root); 15505d4f98a2SYan Zheng reloc_root->commit_root = btrfs_root_node(reloc_root); 15515d4f98a2SYan Zheng } 15525d4f98a2SYan Zheng 15530b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 15545d4f98a2SYan Zheng &reloc_root->root_key, root_item); 15555d4f98a2SYan Zheng BUG_ON(ret); 1556f44deb74SJosef Bacik btrfs_put_root(reloc_root); 15577585717fSChris Mason out: 15585d4f98a2SYan Zheng return 0; 15595d4f98a2SYan Zheng } 15605d4f98a2SYan Zheng 15615d4f98a2SYan Zheng /* 15625d4f98a2SYan Zheng * helper to find first cached inode with inode number >= objectid 15635d4f98a2SYan Zheng * in a subvolume 15645d4f98a2SYan Zheng */ 15655d4f98a2SYan Zheng static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) 15665d4f98a2SYan Zheng { 15675d4f98a2SYan Zheng struct rb_node *node; 15685d4f98a2SYan Zheng struct rb_node *prev; 15695d4f98a2SYan Zheng struct btrfs_inode *entry; 15705d4f98a2SYan Zheng struct inode *inode; 15715d4f98a2SYan Zheng 15725d4f98a2SYan Zheng spin_lock(&root->inode_lock); 15735d4f98a2SYan Zheng again: 15745d4f98a2SYan Zheng node = root->inode_tree.rb_node; 15755d4f98a2SYan Zheng prev = NULL; 15765d4f98a2SYan Zheng while (node) { 15775d4f98a2SYan Zheng prev = node; 15785d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 15795d4f98a2SYan Zheng 15804a0cc7caSNikolay Borisov if (objectid < btrfs_ino(entry)) 15815d4f98a2SYan Zheng node = node->rb_left; 15824a0cc7caSNikolay Borisov else if (objectid > btrfs_ino(entry)) 15835d4f98a2SYan Zheng node = node->rb_right; 15845d4f98a2SYan Zheng else 15855d4f98a2SYan Zheng break; 15865d4f98a2SYan Zheng } 15875d4f98a2SYan Zheng if (!node) { 15885d4f98a2SYan Zheng while (prev) { 15895d4f98a2SYan Zheng entry = rb_entry(prev, struct btrfs_inode, rb_node); 15904a0cc7caSNikolay Borisov if (objectid <= btrfs_ino(entry)) { 15915d4f98a2SYan Zheng node = prev; 15925d4f98a2SYan Zheng break; 15935d4f98a2SYan Zheng } 15945d4f98a2SYan Zheng prev = rb_next(prev); 15955d4f98a2SYan Zheng } 15965d4f98a2SYan Zheng } 15975d4f98a2SYan Zheng while (node) { 15985d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 15995d4f98a2SYan Zheng inode = igrab(&entry->vfs_inode); 16005d4f98a2SYan Zheng if (inode) { 16015d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 16025d4f98a2SYan Zheng return inode; 16035d4f98a2SYan Zheng } 16045d4f98a2SYan Zheng 16054a0cc7caSNikolay Borisov objectid = btrfs_ino(entry) + 1; 16065d4f98a2SYan Zheng if (cond_resched_lock(&root->inode_lock)) 16075d4f98a2SYan Zheng goto again; 16085d4f98a2SYan Zheng 16095d4f98a2SYan Zheng node = rb_next(node); 16105d4f98a2SYan Zheng } 16115d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 16125d4f98a2SYan Zheng return NULL; 16135d4f98a2SYan Zheng } 16145d4f98a2SYan Zheng 161532da5386SDavid Sterba static int in_block_group(u64 bytenr, struct btrfs_block_group *block_group) 16165d4f98a2SYan Zheng { 1617b3470b5dSDavid Sterba if (bytenr >= block_group->start && 1618b3470b5dSDavid Sterba bytenr < block_group->start + block_group->length) 16195d4f98a2SYan Zheng return 1; 16205d4f98a2SYan Zheng return 0; 16215d4f98a2SYan Zheng } 16225d4f98a2SYan Zheng 16235d4f98a2SYan Zheng /* 16245d4f98a2SYan Zheng * get new location of data 16255d4f98a2SYan Zheng */ 16265d4f98a2SYan Zheng static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, 16275d4f98a2SYan Zheng u64 bytenr, u64 num_bytes) 16285d4f98a2SYan Zheng { 16295d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(reloc_inode)->root; 16305d4f98a2SYan Zheng struct btrfs_path *path; 16315d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 16325d4f98a2SYan Zheng struct extent_buffer *leaf; 16335d4f98a2SYan Zheng int ret; 16345d4f98a2SYan Zheng 16355d4f98a2SYan Zheng path = btrfs_alloc_path(); 16365d4f98a2SYan Zheng if (!path) 16375d4f98a2SYan Zheng return -ENOMEM; 16385d4f98a2SYan Zheng 16395d4f98a2SYan Zheng bytenr -= BTRFS_I(reloc_inode)->index_cnt; 1640f85b7379SDavid Sterba ret = btrfs_lookup_file_extent(NULL, root, path, 1641f85b7379SDavid Sterba btrfs_ino(BTRFS_I(reloc_inode)), bytenr, 0); 16425d4f98a2SYan Zheng if (ret < 0) 16435d4f98a2SYan Zheng goto out; 16445d4f98a2SYan Zheng if (ret > 0) { 16455d4f98a2SYan Zheng ret = -ENOENT; 16465d4f98a2SYan Zheng goto out; 16475d4f98a2SYan Zheng } 16485d4f98a2SYan Zheng 16495d4f98a2SYan Zheng leaf = path->nodes[0]; 16505d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, path->slots[0], 16515d4f98a2SYan Zheng struct btrfs_file_extent_item); 16525d4f98a2SYan Zheng 16535d4f98a2SYan Zheng BUG_ON(btrfs_file_extent_offset(leaf, fi) || 16545d4f98a2SYan Zheng btrfs_file_extent_compression(leaf, fi) || 16555d4f98a2SYan Zheng btrfs_file_extent_encryption(leaf, fi) || 16565d4f98a2SYan Zheng btrfs_file_extent_other_encoding(leaf, fi)); 16575d4f98a2SYan Zheng 16585d4f98a2SYan Zheng if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { 165983d4cfd4SJosef Bacik ret = -EINVAL; 16605d4f98a2SYan Zheng goto out; 16615d4f98a2SYan Zheng } 16625d4f98a2SYan Zheng 16635d4f98a2SYan Zheng *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 16645d4f98a2SYan Zheng ret = 0; 16655d4f98a2SYan Zheng out: 16665d4f98a2SYan Zheng btrfs_free_path(path); 16675d4f98a2SYan Zheng return ret; 16685d4f98a2SYan Zheng } 16695d4f98a2SYan Zheng 16705d4f98a2SYan Zheng /* 16715d4f98a2SYan Zheng * update file extent items in the tree leaf to point to 16725d4f98a2SYan Zheng * the new locations. 16735d4f98a2SYan Zheng */ 16743fd0a558SYan, Zheng static noinline_for_stack 16753fd0a558SYan, Zheng int replace_file_extents(struct btrfs_trans_handle *trans, 16765d4f98a2SYan Zheng struct reloc_control *rc, 16775d4f98a2SYan Zheng struct btrfs_root *root, 16783fd0a558SYan, Zheng struct extent_buffer *leaf) 16795d4f98a2SYan Zheng { 16800b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 16815d4f98a2SYan Zheng struct btrfs_key key; 16825d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 16835d4f98a2SYan Zheng struct inode *inode = NULL; 16845d4f98a2SYan Zheng u64 parent; 16855d4f98a2SYan Zheng u64 bytenr; 16863fd0a558SYan, Zheng u64 new_bytenr = 0; 16875d4f98a2SYan Zheng u64 num_bytes; 16885d4f98a2SYan Zheng u64 end; 16895d4f98a2SYan Zheng u32 nritems; 16905d4f98a2SYan Zheng u32 i; 169183d4cfd4SJosef Bacik int ret = 0; 16925d4f98a2SYan Zheng int first = 1; 16935d4f98a2SYan Zheng int dirty = 0; 16945d4f98a2SYan Zheng 16955d4f98a2SYan Zheng if (rc->stage != UPDATE_DATA_PTRS) 16965d4f98a2SYan Zheng return 0; 16975d4f98a2SYan Zheng 16985d4f98a2SYan Zheng /* reloc trees always use full backref */ 16995d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 17005d4f98a2SYan Zheng parent = leaf->start; 17015d4f98a2SYan Zheng else 17025d4f98a2SYan Zheng parent = 0; 17035d4f98a2SYan Zheng 17045d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 17055d4f98a2SYan Zheng for (i = 0; i < nritems; i++) { 170682fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 170782fa113fSQu Wenruo 17085d4f98a2SYan Zheng cond_resched(); 17095d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, i); 17105d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_DATA_KEY) 17115d4f98a2SYan Zheng continue; 17125d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 17135d4f98a2SYan Zheng if (btrfs_file_extent_type(leaf, fi) == 17145d4f98a2SYan Zheng BTRFS_FILE_EXTENT_INLINE) 17155d4f98a2SYan Zheng continue; 17165d4f98a2SYan Zheng bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 17175d4f98a2SYan Zheng num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); 17185d4f98a2SYan Zheng if (bytenr == 0) 17195d4f98a2SYan Zheng continue; 17205d4f98a2SYan Zheng if (!in_block_group(bytenr, rc->block_group)) 17215d4f98a2SYan Zheng continue; 17225d4f98a2SYan Zheng 17235d4f98a2SYan Zheng /* 17245d4f98a2SYan Zheng * if we are modifying block in fs tree, wait for readpage 17255d4f98a2SYan Zheng * to complete and drop the extent cache 17265d4f98a2SYan Zheng */ 17275d4f98a2SYan Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 17285d4f98a2SYan Zheng if (first) { 17295d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 17305d4f98a2SYan Zheng first = 0; 17314a0cc7caSNikolay Borisov } else if (inode && btrfs_ino(BTRFS_I(inode)) < key.objectid) { 17323fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 17335d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 17345d4f98a2SYan Zheng } 17354a0cc7caSNikolay Borisov if (inode && btrfs_ino(BTRFS_I(inode)) == key.objectid) { 17365d4f98a2SYan Zheng end = key.offset + 17375d4f98a2SYan Zheng btrfs_file_extent_num_bytes(leaf, fi); 17385d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(key.offset, 17390b246afaSJeff Mahoney fs_info->sectorsize)); 17400b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 17415d4f98a2SYan Zheng end--; 17425d4f98a2SYan Zheng ret = try_lock_extent(&BTRFS_I(inode)->io_tree, 1743d0082371SJeff Mahoney key.offset, end); 17445d4f98a2SYan Zheng if (!ret) 17455d4f98a2SYan Zheng continue; 17465d4f98a2SYan Zheng 1747dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), 1748dcdbc059SNikolay Borisov key.offset, end, 1); 17495d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 1750d0082371SJeff Mahoney key.offset, end); 17515d4f98a2SYan Zheng } 17525d4f98a2SYan Zheng } 17535d4f98a2SYan Zheng 17545d4f98a2SYan Zheng ret = get_new_location(rc->data_inode, &new_bytenr, 17555d4f98a2SYan Zheng bytenr, num_bytes); 175683d4cfd4SJosef Bacik if (ret) { 175783d4cfd4SJosef Bacik /* 175883d4cfd4SJosef Bacik * Don't have to abort since we've not changed anything 175983d4cfd4SJosef Bacik * in the file extent yet. 176083d4cfd4SJosef Bacik */ 176183d4cfd4SJosef Bacik break; 17623fd0a558SYan, Zheng } 17635d4f98a2SYan Zheng 17645d4f98a2SYan Zheng btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); 17655d4f98a2SYan Zheng dirty = 1; 17665d4f98a2SYan Zheng 17675d4f98a2SYan Zheng key.offset -= btrfs_file_extent_offset(leaf, fi); 176882fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 176982fa113fSQu Wenruo num_bytes, parent); 177082fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 177182fa113fSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1772b06c4bf5SFilipe Manana key.objectid, key.offset); 177382fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 177483d4cfd4SJosef Bacik if (ret) { 177566642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 177683d4cfd4SJosef Bacik break; 177783d4cfd4SJosef Bacik } 17785d4f98a2SYan Zheng 1779ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr, 1780ffd4bb2aSQu Wenruo num_bytes, parent); 1781ffd4bb2aSQu Wenruo ref.real_root = root->root_key.objectid; 1782ffd4bb2aSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1783b06c4bf5SFilipe Manana key.objectid, key.offset); 1784ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 178583d4cfd4SJosef Bacik if (ret) { 178666642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 178783d4cfd4SJosef Bacik break; 178883d4cfd4SJosef Bacik } 17895d4f98a2SYan Zheng } 17905d4f98a2SYan Zheng if (dirty) 17915d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 17923fd0a558SYan, Zheng if (inode) 17933fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 179483d4cfd4SJosef Bacik return ret; 17955d4f98a2SYan Zheng } 17965d4f98a2SYan Zheng 17975d4f98a2SYan Zheng static noinline_for_stack 17985d4f98a2SYan Zheng int memcmp_node_keys(struct extent_buffer *eb, int slot, 17995d4f98a2SYan Zheng struct btrfs_path *path, int level) 18005d4f98a2SYan Zheng { 18015d4f98a2SYan Zheng struct btrfs_disk_key key1; 18025d4f98a2SYan Zheng struct btrfs_disk_key key2; 18035d4f98a2SYan Zheng btrfs_node_key(eb, &key1, slot); 18045d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &key2, path->slots[level]); 18055d4f98a2SYan Zheng return memcmp(&key1, &key2, sizeof(key1)); 18065d4f98a2SYan Zheng } 18075d4f98a2SYan Zheng 18085d4f98a2SYan Zheng /* 18095d4f98a2SYan Zheng * try to replace tree blocks in fs tree with the new blocks 18105d4f98a2SYan Zheng * in reloc tree. tree blocks haven't been modified since the 18115d4f98a2SYan Zheng * reloc tree was create can be replaced. 18125d4f98a2SYan Zheng * 18135d4f98a2SYan Zheng * if a block was replaced, level of the block + 1 is returned. 18145d4f98a2SYan Zheng * if no block got replaced, 0 is returned. if there are other 18155d4f98a2SYan Zheng * errors, a negative error number is returned. 18165d4f98a2SYan Zheng */ 18173fd0a558SYan, Zheng static noinline_for_stack 18183d0174f7SQu Wenruo int replace_path(struct btrfs_trans_handle *trans, struct reloc_control *rc, 18195d4f98a2SYan Zheng struct btrfs_root *dest, struct btrfs_root *src, 18205d4f98a2SYan Zheng struct btrfs_path *path, struct btrfs_key *next_key, 18215d4f98a2SYan Zheng int lowest_level, int max_level) 18225d4f98a2SYan Zheng { 18230b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = dest->fs_info; 18245d4f98a2SYan Zheng struct extent_buffer *eb; 18255d4f98a2SYan Zheng struct extent_buffer *parent; 182682fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 18275d4f98a2SYan Zheng struct btrfs_key key; 18285d4f98a2SYan Zheng u64 old_bytenr; 18295d4f98a2SYan Zheng u64 new_bytenr; 18305d4f98a2SYan Zheng u64 old_ptr_gen; 18315d4f98a2SYan Zheng u64 new_ptr_gen; 18325d4f98a2SYan Zheng u64 last_snapshot; 18335d4f98a2SYan Zheng u32 blocksize; 18343fd0a558SYan, Zheng int cow = 0; 18355d4f98a2SYan Zheng int level; 18365d4f98a2SYan Zheng int ret; 18375d4f98a2SYan Zheng int slot; 18385d4f98a2SYan Zheng 18395d4f98a2SYan Zheng BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 18405d4f98a2SYan Zheng BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); 18415d4f98a2SYan Zheng 18425d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&src->root_item); 18433fd0a558SYan, Zheng again: 18445d4f98a2SYan Zheng slot = path->slots[lowest_level]; 18455d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); 18465d4f98a2SYan Zheng 18475d4f98a2SYan Zheng eb = btrfs_lock_root_node(dest); 18488bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 18495d4f98a2SYan Zheng level = btrfs_header_level(eb); 18505d4f98a2SYan Zheng 18515d4f98a2SYan Zheng if (level < lowest_level) { 18525d4f98a2SYan Zheng btrfs_tree_unlock(eb); 18535d4f98a2SYan Zheng free_extent_buffer(eb); 18545d4f98a2SYan Zheng return 0; 18555d4f98a2SYan Zheng } 18565d4f98a2SYan Zheng 18573fd0a558SYan, Zheng if (cow) { 18585d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); 18595d4f98a2SYan Zheng BUG_ON(ret); 18603fd0a558SYan, Zheng } 18618bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 18625d4f98a2SYan Zheng 18635d4f98a2SYan Zheng if (next_key) { 18645d4f98a2SYan Zheng next_key->objectid = (u64)-1; 18655d4f98a2SYan Zheng next_key->type = (u8)-1; 18665d4f98a2SYan Zheng next_key->offset = (u64)-1; 18675d4f98a2SYan Zheng } 18685d4f98a2SYan Zheng 18695d4f98a2SYan Zheng parent = eb; 18705d4f98a2SYan Zheng while (1) { 1871581c1760SQu Wenruo struct btrfs_key first_key; 1872581c1760SQu Wenruo 18735d4f98a2SYan Zheng level = btrfs_header_level(parent); 18745d4f98a2SYan Zheng BUG_ON(level < lowest_level); 18755d4f98a2SYan Zheng 18765d4f98a2SYan Zheng ret = btrfs_bin_search(parent, &key, level, &slot); 1877cbca7d59SFilipe Manana if (ret < 0) 1878cbca7d59SFilipe Manana break; 18795d4f98a2SYan Zheng if (ret && slot > 0) 18805d4f98a2SYan Zheng slot--; 18815d4f98a2SYan Zheng 18825d4f98a2SYan Zheng if (next_key && slot + 1 < btrfs_header_nritems(parent)) 18835d4f98a2SYan Zheng btrfs_node_key_to_cpu(parent, next_key, slot + 1); 18845d4f98a2SYan Zheng 18855d4f98a2SYan Zheng old_bytenr = btrfs_node_blockptr(parent, slot); 18860b246afaSJeff Mahoney blocksize = fs_info->nodesize; 18875d4f98a2SYan Zheng old_ptr_gen = btrfs_node_ptr_generation(parent, slot); 188817515f1bSQu Wenruo btrfs_node_key_to_cpu(parent, &first_key, slot); 18895d4f98a2SYan Zheng 18905d4f98a2SYan Zheng if (level <= max_level) { 18915d4f98a2SYan Zheng eb = path->nodes[level]; 18925d4f98a2SYan Zheng new_bytenr = btrfs_node_blockptr(eb, 18935d4f98a2SYan Zheng path->slots[level]); 18945d4f98a2SYan Zheng new_ptr_gen = btrfs_node_ptr_generation(eb, 18955d4f98a2SYan Zheng path->slots[level]); 18965d4f98a2SYan Zheng } else { 18975d4f98a2SYan Zheng new_bytenr = 0; 18985d4f98a2SYan Zheng new_ptr_gen = 0; 18995d4f98a2SYan Zheng } 19005d4f98a2SYan Zheng 1901fae7f21cSDulshani Gunawardhana if (WARN_ON(new_bytenr > 0 && new_bytenr == old_bytenr)) { 19025d4f98a2SYan Zheng ret = level; 19035d4f98a2SYan Zheng break; 19045d4f98a2SYan Zheng } 19055d4f98a2SYan Zheng 19065d4f98a2SYan Zheng if (new_bytenr == 0 || old_ptr_gen > last_snapshot || 19075d4f98a2SYan Zheng memcmp_node_keys(parent, slot, path, level)) { 19083fd0a558SYan, Zheng if (level <= lowest_level) { 19095d4f98a2SYan Zheng ret = 0; 19105d4f98a2SYan Zheng break; 19115d4f98a2SYan Zheng } 19125d4f98a2SYan Zheng 1913581c1760SQu Wenruo eb = read_tree_block(fs_info, old_bytenr, old_ptr_gen, 1914581c1760SQu Wenruo level - 1, &first_key); 191564c043deSLiu Bo if (IS_ERR(eb)) { 191664c043deSLiu Bo ret = PTR_ERR(eb); 1917264813acSLiu Bo break; 191864c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 191964c043deSLiu Bo ret = -EIO; 1920416bc658SJosef Bacik free_extent_buffer(eb); 1921379cde74SStefan Behrens break; 1922416bc658SJosef Bacik } 19235d4f98a2SYan Zheng btrfs_tree_lock(eb); 19243fd0a558SYan, Zheng if (cow) { 19255d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, parent, 19265d4f98a2SYan Zheng slot, &eb); 19275d4f98a2SYan Zheng BUG_ON(ret); 19285d4f98a2SYan Zheng } 19298bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 19305d4f98a2SYan Zheng 19315d4f98a2SYan Zheng btrfs_tree_unlock(parent); 19325d4f98a2SYan Zheng free_extent_buffer(parent); 19335d4f98a2SYan Zheng 19345d4f98a2SYan Zheng parent = eb; 19355d4f98a2SYan Zheng continue; 19365d4f98a2SYan Zheng } 19375d4f98a2SYan Zheng 19383fd0a558SYan, Zheng if (!cow) { 19393fd0a558SYan, Zheng btrfs_tree_unlock(parent); 19403fd0a558SYan, Zheng free_extent_buffer(parent); 19413fd0a558SYan, Zheng cow = 1; 19423fd0a558SYan, Zheng goto again; 19433fd0a558SYan, Zheng } 19443fd0a558SYan, Zheng 19455d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 19465d4f98a2SYan Zheng path->slots[level]); 1947b3b4aa74SDavid Sterba btrfs_release_path(path); 19485d4f98a2SYan Zheng 19495d4f98a2SYan Zheng path->lowest_level = level; 19505d4f98a2SYan Zheng ret = btrfs_search_slot(trans, src, &key, path, 0, 1); 19515d4f98a2SYan Zheng path->lowest_level = 0; 19525d4f98a2SYan Zheng BUG_ON(ret); 19535d4f98a2SYan Zheng 19545d4f98a2SYan Zheng /* 1955824d8dffSQu Wenruo * Info qgroup to trace both subtrees. 1956824d8dffSQu Wenruo * 1957824d8dffSQu Wenruo * We must trace both trees. 1958824d8dffSQu Wenruo * 1) Tree reloc subtree 1959824d8dffSQu Wenruo * If not traced, we will leak data numbers 1960824d8dffSQu Wenruo * 2) Fs subtree 1961824d8dffSQu Wenruo * If not traced, we will double count old data 1962f616f5cdSQu Wenruo * 1963f616f5cdSQu Wenruo * We don't scan the subtree right now, but only record 1964f616f5cdSQu Wenruo * the swapped tree blocks. 1965f616f5cdSQu Wenruo * The real subtree rescan is delayed until we have new 1966f616f5cdSQu Wenruo * CoW on the subtree root node before transaction commit. 1967824d8dffSQu Wenruo */ 1968370a11b8SQu Wenruo ret = btrfs_qgroup_add_swapped_blocks(trans, dest, 1969370a11b8SQu Wenruo rc->block_group, parent, slot, 1970370a11b8SQu Wenruo path->nodes[level], path->slots[level], 1971370a11b8SQu Wenruo last_snapshot); 1972370a11b8SQu Wenruo if (ret < 0) 1973370a11b8SQu Wenruo break; 1974824d8dffSQu Wenruo /* 19755d4f98a2SYan Zheng * swap blocks in fs tree and reloc tree. 19765d4f98a2SYan Zheng */ 19775d4f98a2SYan Zheng btrfs_set_node_blockptr(parent, slot, new_bytenr); 19785d4f98a2SYan Zheng btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); 19795d4f98a2SYan Zheng btrfs_mark_buffer_dirty(parent); 19805d4f98a2SYan Zheng 19815d4f98a2SYan Zheng btrfs_set_node_blockptr(path->nodes[level], 19825d4f98a2SYan Zheng path->slots[level], old_bytenr); 19835d4f98a2SYan Zheng btrfs_set_node_ptr_generation(path->nodes[level], 19845d4f98a2SYan Zheng path->slots[level], old_ptr_gen); 19855d4f98a2SYan Zheng btrfs_mark_buffer_dirty(path->nodes[level]); 19865d4f98a2SYan Zheng 198782fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, old_bytenr, 198882fa113fSQu Wenruo blocksize, path->nodes[level]->start); 198982fa113fSQu Wenruo ref.skip_qgroup = true; 199082fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 199182fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 19925d4f98a2SYan Zheng BUG_ON(ret); 199382fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 199482fa113fSQu Wenruo blocksize, 0); 199582fa113fSQu Wenruo ref.skip_qgroup = true; 199682fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 199782fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 19985d4f98a2SYan Zheng BUG_ON(ret); 19995d4f98a2SYan Zheng 2000ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, new_bytenr, 2001ffd4bb2aSQu Wenruo blocksize, path->nodes[level]->start); 2002ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 2003ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 2004ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 20055d4f98a2SYan Zheng BUG_ON(ret); 20065d4f98a2SYan Zheng 2007ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, old_bytenr, 2008ffd4bb2aSQu Wenruo blocksize, 0); 2009ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 2010ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 2011ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 20125d4f98a2SYan Zheng BUG_ON(ret); 20135d4f98a2SYan Zheng 20145d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 20155d4f98a2SYan Zheng 20165d4f98a2SYan Zheng ret = level; 20175d4f98a2SYan Zheng break; 20185d4f98a2SYan Zheng } 20195d4f98a2SYan Zheng btrfs_tree_unlock(parent); 20205d4f98a2SYan Zheng free_extent_buffer(parent); 20215d4f98a2SYan Zheng return ret; 20225d4f98a2SYan Zheng } 20235d4f98a2SYan Zheng 20245d4f98a2SYan Zheng /* 20255d4f98a2SYan Zheng * helper to find next relocated block in reloc tree 20265d4f98a2SYan Zheng */ 20275d4f98a2SYan Zheng static noinline_for_stack 20285d4f98a2SYan Zheng int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 20295d4f98a2SYan Zheng int *level) 20305d4f98a2SYan Zheng { 20315d4f98a2SYan Zheng struct extent_buffer *eb; 20325d4f98a2SYan Zheng int i; 20335d4f98a2SYan Zheng u64 last_snapshot; 20345d4f98a2SYan Zheng u32 nritems; 20355d4f98a2SYan Zheng 20365d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 20375d4f98a2SYan Zheng 20385d4f98a2SYan Zheng for (i = 0; i < *level; i++) { 20395d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 20405d4f98a2SYan Zheng path->nodes[i] = NULL; 20415d4f98a2SYan Zheng } 20425d4f98a2SYan Zheng 20435d4f98a2SYan Zheng for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { 20445d4f98a2SYan Zheng eb = path->nodes[i]; 20455d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 20465d4f98a2SYan Zheng while (path->slots[i] + 1 < nritems) { 20475d4f98a2SYan Zheng path->slots[i]++; 20485d4f98a2SYan Zheng if (btrfs_node_ptr_generation(eb, path->slots[i]) <= 20495d4f98a2SYan Zheng last_snapshot) 20505d4f98a2SYan Zheng continue; 20515d4f98a2SYan Zheng 20525d4f98a2SYan Zheng *level = i; 20535d4f98a2SYan Zheng return 0; 20545d4f98a2SYan Zheng } 20555d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 20565d4f98a2SYan Zheng path->nodes[i] = NULL; 20575d4f98a2SYan Zheng } 20585d4f98a2SYan Zheng return 1; 20595d4f98a2SYan Zheng } 20605d4f98a2SYan Zheng 20615d4f98a2SYan Zheng /* 20625d4f98a2SYan Zheng * walk down reloc tree to find relocated block of lowest level 20635d4f98a2SYan Zheng */ 20645d4f98a2SYan Zheng static noinline_for_stack 20655d4f98a2SYan Zheng int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 20665d4f98a2SYan Zheng int *level) 20675d4f98a2SYan Zheng { 20682ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 20695d4f98a2SYan Zheng struct extent_buffer *eb = NULL; 20705d4f98a2SYan Zheng int i; 20715d4f98a2SYan Zheng u64 bytenr; 20725d4f98a2SYan Zheng u64 ptr_gen = 0; 20735d4f98a2SYan Zheng u64 last_snapshot; 20745d4f98a2SYan Zheng u32 nritems; 20755d4f98a2SYan Zheng 20765d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 20775d4f98a2SYan Zheng 20785d4f98a2SYan Zheng for (i = *level; i > 0; i--) { 2079581c1760SQu Wenruo struct btrfs_key first_key; 2080581c1760SQu Wenruo 20815d4f98a2SYan Zheng eb = path->nodes[i]; 20825d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 20835d4f98a2SYan Zheng while (path->slots[i] < nritems) { 20845d4f98a2SYan Zheng ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); 20855d4f98a2SYan Zheng if (ptr_gen > last_snapshot) 20865d4f98a2SYan Zheng break; 20875d4f98a2SYan Zheng path->slots[i]++; 20885d4f98a2SYan Zheng } 20895d4f98a2SYan Zheng if (path->slots[i] >= nritems) { 20905d4f98a2SYan Zheng if (i == *level) 20915d4f98a2SYan Zheng break; 20925d4f98a2SYan Zheng *level = i + 1; 20935d4f98a2SYan Zheng return 0; 20945d4f98a2SYan Zheng } 20955d4f98a2SYan Zheng if (i == 1) { 20965d4f98a2SYan Zheng *level = i; 20975d4f98a2SYan Zheng return 0; 20985d4f98a2SYan Zheng } 20995d4f98a2SYan Zheng 21005d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(eb, path->slots[i]); 2101581c1760SQu Wenruo btrfs_node_key_to_cpu(eb, &first_key, path->slots[i]); 2102581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, ptr_gen, i - 1, 2103581c1760SQu Wenruo &first_key); 210464c043deSLiu Bo if (IS_ERR(eb)) { 210564c043deSLiu Bo return PTR_ERR(eb); 210664c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2107416bc658SJosef Bacik free_extent_buffer(eb); 2108416bc658SJosef Bacik return -EIO; 2109416bc658SJosef Bacik } 21105d4f98a2SYan Zheng BUG_ON(btrfs_header_level(eb) != i - 1); 21115d4f98a2SYan Zheng path->nodes[i - 1] = eb; 21125d4f98a2SYan Zheng path->slots[i - 1] = 0; 21135d4f98a2SYan Zheng } 21145d4f98a2SYan Zheng return 1; 21155d4f98a2SYan Zheng } 21165d4f98a2SYan Zheng 21175d4f98a2SYan Zheng /* 21185d4f98a2SYan Zheng * invalidate extent cache for file extents whose key in range of 21195d4f98a2SYan Zheng * [min_key, max_key) 21205d4f98a2SYan Zheng */ 21215d4f98a2SYan Zheng static int invalidate_extent_cache(struct btrfs_root *root, 21225d4f98a2SYan Zheng struct btrfs_key *min_key, 21235d4f98a2SYan Zheng struct btrfs_key *max_key) 21245d4f98a2SYan Zheng { 21250b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 21265d4f98a2SYan Zheng struct inode *inode = NULL; 21275d4f98a2SYan Zheng u64 objectid; 21285d4f98a2SYan Zheng u64 start, end; 212933345d01SLi Zefan u64 ino; 21305d4f98a2SYan Zheng 21315d4f98a2SYan Zheng objectid = min_key->objectid; 21325d4f98a2SYan Zheng while (1) { 21335d4f98a2SYan Zheng cond_resched(); 21345d4f98a2SYan Zheng iput(inode); 21355d4f98a2SYan Zheng 21365d4f98a2SYan Zheng if (objectid > max_key->objectid) 21375d4f98a2SYan Zheng break; 21385d4f98a2SYan Zheng 21395d4f98a2SYan Zheng inode = find_next_inode(root, objectid); 21405d4f98a2SYan Zheng if (!inode) 21415d4f98a2SYan Zheng break; 21424a0cc7caSNikolay Borisov ino = btrfs_ino(BTRFS_I(inode)); 21435d4f98a2SYan Zheng 214433345d01SLi Zefan if (ino > max_key->objectid) { 21455d4f98a2SYan Zheng iput(inode); 21465d4f98a2SYan Zheng break; 21475d4f98a2SYan Zheng } 21485d4f98a2SYan Zheng 214933345d01SLi Zefan objectid = ino + 1; 21505d4f98a2SYan Zheng if (!S_ISREG(inode->i_mode)) 21515d4f98a2SYan Zheng continue; 21525d4f98a2SYan Zheng 215333345d01SLi Zefan if (unlikely(min_key->objectid == ino)) { 21545d4f98a2SYan Zheng if (min_key->type > BTRFS_EXTENT_DATA_KEY) 21555d4f98a2SYan Zheng continue; 21565d4f98a2SYan Zheng if (min_key->type < BTRFS_EXTENT_DATA_KEY) 21575d4f98a2SYan Zheng start = 0; 21585d4f98a2SYan Zheng else { 21595d4f98a2SYan Zheng start = min_key->offset; 21600b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(start, fs_info->sectorsize)); 21615d4f98a2SYan Zheng } 21625d4f98a2SYan Zheng } else { 21635d4f98a2SYan Zheng start = 0; 21645d4f98a2SYan Zheng } 21655d4f98a2SYan Zheng 216633345d01SLi Zefan if (unlikely(max_key->objectid == ino)) { 21675d4f98a2SYan Zheng if (max_key->type < BTRFS_EXTENT_DATA_KEY) 21685d4f98a2SYan Zheng continue; 21695d4f98a2SYan Zheng if (max_key->type > BTRFS_EXTENT_DATA_KEY) { 21705d4f98a2SYan Zheng end = (u64)-1; 21715d4f98a2SYan Zheng } else { 21725d4f98a2SYan Zheng if (max_key->offset == 0) 21735d4f98a2SYan Zheng continue; 21745d4f98a2SYan Zheng end = max_key->offset; 21750b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 21765d4f98a2SYan Zheng end--; 21775d4f98a2SYan Zheng } 21785d4f98a2SYan Zheng } else { 21795d4f98a2SYan Zheng end = (u64)-1; 21805d4f98a2SYan Zheng } 21815d4f98a2SYan Zheng 21825d4f98a2SYan Zheng /* the lock_extent waits for readpage to complete */ 2183d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 2184dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 1); 2185d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 21865d4f98a2SYan Zheng } 21875d4f98a2SYan Zheng return 0; 21885d4f98a2SYan Zheng } 21895d4f98a2SYan Zheng 21905d4f98a2SYan Zheng static int find_next_key(struct btrfs_path *path, int level, 21915d4f98a2SYan Zheng struct btrfs_key *key) 21925d4f98a2SYan Zheng 21935d4f98a2SYan Zheng { 21945d4f98a2SYan Zheng while (level < BTRFS_MAX_LEVEL) { 21955d4f98a2SYan Zheng if (!path->nodes[level]) 21965d4f98a2SYan Zheng break; 21975d4f98a2SYan Zheng if (path->slots[level] + 1 < 21985d4f98a2SYan Zheng btrfs_header_nritems(path->nodes[level])) { 21995d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], key, 22005d4f98a2SYan Zheng path->slots[level] + 1); 22015d4f98a2SYan Zheng return 0; 22025d4f98a2SYan Zheng } 22035d4f98a2SYan Zheng level++; 22045d4f98a2SYan Zheng } 22055d4f98a2SYan Zheng return 1; 22065d4f98a2SYan Zheng } 22075d4f98a2SYan Zheng 22085d4f98a2SYan Zheng /* 2209d2311e69SQu Wenruo * Insert current subvolume into reloc_control::dirty_subvol_roots 2210d2311e69SQu Wenruo */ 2211d2311e69SQu Wenruo static void insert_dirty_subvol(struct btrfs_trans_handle *trans, 2212d2311e69SQu Wenruo struct reloc_control *rc, 2213d2311e69SQu Wenruo struct btrfs_root *root) 2214d2311e69SQu Wenruo { 2215d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2216d2311e69SQu Wenruo struct btrfs_root_item *reloc_root_item; 2217d2311e69SQu Wenruo 2218d2311e69SQu Wenruo /* @root must be a subvolume tree root with a valid reloc tree */ 2219d2311e69SQu Wenruo ASSERT(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 2220d2311e69SQu Wenruo ASSERT(reloc_root); 2221d2311e69SQu Wenruo 2222d2311e69SQu Wenruo reloc_root_item = &reloc_root->root_item; 2223d2311e69SQu Wenruo memset(&reloc_root_item->drop_progress, 0, 2224d2311e69SQu Wenruo sizeof(reloc_root_item->drop_progress)); 2225d2311e69SQu Wenruo reloc_root_item->drop_level = 0; 2226d2311e69SQu Wenruo btrfs_set_root_refs(reloc_root_item, 0); 2227d2311e69SQu Wenruo btrfs_update_reloc_root(trans, root); 2228d2311e69SQu Wenruo 2229d2311e69SQu Wenruo if (list_empty(&root->reloc_dirty_list)) { 223000246528SJosef Bacik btrfs_grab_root(root); 2231d2311e69SQu Wenruo list_add_tail(&root->reloc_dirty_list, &rc->dirty_subvol_roots); 2232d2311e69SQu Wenruo } 2233d2311e69SQu Wenruo } 2234d2311e69SQu Wenruo 2235d2311e69SQu Wenruo static int clean_dirty_subvols(struct reloc_control *rc) 2236d2311e69SQu Wenruo { 2237d2311e69SQu Wenruo struct btrfs_root *root; 2238d2311e69SQu Wenruo struct btrfs_root *next; 2239d2311e69SQu Wenruo int ret = 0; 224030d40577SQu Wenruo int ret2; 2241d2311e69SQu Wenruo 2242d2311e69SQu Wenruo list_for_each_entry_safe(root, next, &rc->dirty_subvol_roots, 2243d2311e69SQu Wenruo reloc_dirty_list) { 224430d40577SQu Wenruo if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 224530d40577SQu Wenruo /* Merged subvolume, cleanup its reloc root */ 2246d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2247d2311e69SQu Wenruo 2248d2311e69SQu Wenruo list_del_init(&root->reloc_dirty_list); 2249d2311e69SQu Wenruo root->reloc_root = NULL; 22506282675eSQu Wenruo /* 22516282675eSQu Wenruo * Need barrier to ensure clear_bit() only happens after 22526282675eSQu Wenruo * root->reloc_root = NULL. Pairs with have_reloc_root. 22536282675eSQu Wenruo */ 22546282675eSQu Wenruo smp_wmb(); 22551fac4a54SQu Wenruo clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 2256f28de8d8SJosef Bacik if (reloc_root) { 2257f44deb74SJosef Bacik /* 2258f44deb74SJosef Bacik * btrfs_drop_snapshot drops our ref we hold for 2259f44deb74SJosef Bacik * ->reloc_root. If it fails however we must 2260f44deb74SJosef Bacik * drop the ref ourselves. 2261f44deb74SJosef Bacik */ 2262f28de8d8SJosef Bacik ret2 = btrfs_drop_snapshot(reloc_root, 0, 1); 2263f44deb74SJosef Bacik if (ret2 < 0) { 2264f44deb74SJosef Bacik btrfs_put_root(reloc_root); 2265f44deb74SJosef Bacik if (!ret) 2266f28de8d8SJosef Bacik ret = ret2; 2267f28de8d8SJosef Bacik } 2268f44deb74SJosef Bacik } 226900246528SJosef Bacik btrfs_put_root(root); 227030d40577SQu Wenruo } else { 227130d40577SQu Wenruo /* Orphan reloc tree, just clean it up */ 22720078a9f9SNikolay Borisov ret2 = btrfs_drop_snapshot(root, 0, 1); 2273f44deb74SJosef Bacik if (ret2 < 0) { 2274f44deb74SJosef Bacik btrfs_put_root(root); 2275f44deb74SJosef Bacik if (!ret) 227630d40577SQu Wenruo ret = ret2; 227730d40577SQu Wenruo } 2278d2311e69SQu Wenruo } 2279f44deb74SJosef Bacik } 2280d2311e69SQu Wenruo return ret; 2281d2311e69SQu Wenruo } 2282d2311e69SQu Wenruo 2283d2311e69SQu Wenruo /* 22845d4f98a2SYan Zheng * merge the relocated tree blocks in reloc tree with corresponding 22855d4f98a2SYan Zheng * fs tree. 22865d4f98a2SYan Zheng */ 22875d4f98a2SYan Zheng static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, 22885d4f98a2SYan Zheng struct btrfs_root *root) 22895d4f98a2SYan Zheng { 22900b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 22915d4f98a2SYan Zheng struct btrfs_key key; 22925d4f98a2SYan Zheng struct btrfs_key next_key; 22939e6a0c52SJosef Bacik struct btrfs_trans_handle *trans = NULL; 22945d4f98a2SYan Zheng struct btrfs_root *reloc_root; 22955d4f98a2SYan Zheng struct btrfs_root_item *root_item; 22965d4f98a2SYan Zheng struct btrfs_path *path; 22973fd0a558SYan, Zheng struct extent_buffer *leaf; 22985d4f98a2SYan Zheng int level; 22995d4f98a2SYan Zheng int max_level; 23005d4f98a2SYan Zheng int replaced = 0; 23015d4f98a2SYan Zheng int ret; 23025d4f98a2SYan Zheng int err = 0; 23033fd0a558SYan, Zheng u32 min_reserved; 23045d4f98a2SYan Zheng 23055d4f98a2SYan Zheng path = btrfs_alloc_path(); 23065d4f98a2SYan Zheng if (!path) 23075d4f98a2SYan Zheng return -ENOMEM; 2308e4058b54SDavid Sterba path->reada = READA_FORWARD; 23095d4f98a2SYan Zheng 23105d4f98a2SYan Zheng reloc_root = root->reloc_root; 23115d4f98a2SYan Zheng root_item = &reloc_root->root_item; 23125d4f98a2SYan Zheng 23135d4f98a2SYan Zheng if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { 23145d4f98a2SYan Zheng level = btrfs_root_level(root_item); 231567439dadSDavid Sterba atomic_inc(&reloc_root->node->refs); 23165d4f98a2SYan Zheng path->nodes[level] = reloc_root->node; 23175d4f98a2SYan Zheng path->slots[level] = 0; 23185d4f98a2SYan Zheng } else { 23195d4f98a2SYan Zheng btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); 23205d4f98a2SYan Zheng 23215d4f98a2SYan Zheng level = root_item->drop_level; 23225d4f98a2SYan Zheng BUG_ON(level == 0); 23235d4f98a2SYan Zheng path->lowest_level = level; 23245d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); 232533c66f43SYan Zheng path->lowest_level = 0; 23265d4f98a2SYan Zheng if (ret < 0) { 23275d4f98a2SYan Zheng btrfs_free_path(path); 23285d4f98a2SYan Zheng return ret; 23295d4f98a2SYan Zheng } 23305d4f98a2SYan Zheng 23315d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &next_key, 23325d4f98a2SYan Zheng path->slots[level]); 23335d4f98a2SYan Zheng WARN_ON(memcmp(&key, &next_key, sizeof(key))); 23345d4f98a2SYan Zheng 23355d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 23365d4f98a2SYan Zheng } 23375d4f98a2SYan Zheng 23380b246afaSJeff Mahoney min_reserved = fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 23395d4f98a2SYan Zheng memset(&next_key, 0, sizeof(next_key)); 23405d4f98a2SYan Zheng 23415d4f98a2SYan Zheng while (1) { 234208e007d2SMiao Xie ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved, 234308e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 23443fd0a558SYan, Zheng if (ret) { 23459e6a0c52SJosef Bacik err = ret; 23469e6a0c52SJosef Bacik goto out; 23473fd0a558SYan, Zheng } 23489e6a0c52SJosef Bacik trans = btrfs_start_transaction(root, 0); 23499e6a0c52SJosef Bacik if (IS_ERR(trans)) { 23509e6a0c52SJosef Bacik err = PTR_ERR(trans); 23519e6a0c52SJosef Bacik trans = NULL; 23529e6a0c52SJosef Bacik goto out; 23539e6a0c52SJosef Bacik } 23542abc726aSJosef Bacik 23552abc726aSJosef Bacik /* 23562abc726aSJosef Bacik * At this point we no longer have a reloc_control, so we can't 23572abc726aSJosef Bacik * depend on btrfs_init_reloc_root to update our last_trans. 23582abc726aSJosef Bacik * 23592abc726aSJosef Bacik * But that's ok, we started the trans handle on our 23602abc726aSJosef Bacik * corresponding fs_root, which means it's been added to the 23612abc726aSJosef Bacik * dirty list. At commit time we'll still call 23622abc726aSJosef Bacik * btrfs_update_reloc_root() and update our root item 23632abc726aSJosef Bacik * appropriately. 23642abc726aSJosef Bacik */ 23652abc726aSJosef Bacik reloc_root->last_trans = trans->transid; 23669e6a0c52SJosef Bacik trans->block_rsv = rc->block_rsv; 23673fd0a558SYan, Zheng 23683fd0a558SYan, Zheng replaced = 0; 23695d4f98a2SYan Zheng max_level = level; 23705d4f98a2SYan Zheng 23715d4f98a2SYan Zheng ret = walk_down_reloc_tree(reloc_root, path, &level); 23725d4f98a2SYan Zheng if (ret < 0) { 23735d4f98a2SYan Zheng err = ret; 23745d4f98a2SYan Zheng goto out; 23755d4f98a2SYan Zheng } 23765d4f98a2SYan Zheng if (ret > 0) 23775d4f98a2SYan Zheng break; 23785d4f98a2SYan Zheng 23795d4f98a2SYan Zheng if (!find_next_key(path, level, &key) && 23805d4f98a2SYan Zheng btrfs_comp_cpu_keys(&next_key, &key) >= 0) { 23815d4f98a2SYan Zheng ret = 0; 23825d4f98a2SYan Zheng } else { 23833d0174f7SQu Wenruo ret = replace_path(trans, rc, root, reloc_root, path, 23843fd0a558SYan, Zheng &next_key, level, max_level); 23855d4f98a2SYan Zheng } 23865d4f98a2SYan Zheng if (ret < 0) { 23875d4f98a2SYan Zheng err = ret; 23885d4f98a2SYan Zheng goto out; 23895d4f98a2SYan Zheng } 23905d4f98a2SYan Zheng 23915d4f98a2SYan Zheng if (ret > 0) { 23925d4f98a2SYan Zheng level = ret; 23935d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 23945d4f98a2SYan Zheng path->slots[level]); 23955d4f98a2SYan Zheng replaced = 1; 23965d4f98a2SYan Zheng } 23975d4f98a2SYan Zheng 23985d4f98a2SYan Zheng ret = walk_up_reloc_tree(reloc_root, path, &level); 23995d4f98a2SYan Zheng if (ret > 0) 24005d4f98a2SYan Zheng break; 24015d4f98a2SYan Zheng 24025d4f98a2SYan Zheng BUG_ON(level == 0); 24035d4f98a2SYan Zheng /* 24045d4f98a2SYan Zheng * save the merging progress in the drop_progress. 24055d4f98a2SYan Zheng * this is OK since root refs == 1 in this case. 24065d4f98a2SYan Zheng */ 24075d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &root_item->drop_progress, 24085d4f98a2SYan Zheng path->slots[level]); 24095d4f98a2SYan Zheng root_item->drop_level = level; 24105d4f98a2SYan Zheng 24113a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 24129e6a0c52SJosef Bacik trans = NULL; 24135d4f98a2SYan Zheng 24142ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 24155d4f98a2SYan Zheng 24165d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 24175d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 24185d4f98a2SYan Zheng } 24195d4f98a2SYan Zheng 24205d4f98a2SYan Zheng /* 24215d4f98a2SYan Zheng * handle the case only one block in the fs tree need to be 24225d4f98a2SYan Zheng * relocated and the block is tree root. 24235d4f98a2SYan Zheng */ 24245d4f98a2SYan Zheng leaf = btrfs_lock_root_node(root); 24255d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); 24265d4f98a2SYan Zheng btrfs_tree_unlock(leaf); 24275d4f98a2SYan Zheng free_extent_buffer(leaf); 24285d4f98a2SYan Zheng if (ret < 0) 24295d4f98a2SYan Zheng err = ret; 24305d4f98a2SYan Zheng out: 24315d4f98a2SYan Zheng btrfs_free_path(path); 24325d4f98a2SYan Zheng 2433d2311e69SQu Wenruo if (err == 0) 2434d2311e69SQu Wenruo insert_dirty_subvol(trans, rc, root); 24355d4f98a2SYan Zheng 24369e6a0c52SJosef Bacik if (trans) 24373a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 24385d4f98a2SYan Zheng 24392ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 24405d4f98a2SYan Zheng 24415d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 24425d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 24435d4f98a2SYan Zheng 24445d4f98a2SYan Zheng return err; 24455d4f98a2SYan Zheng } 24465d4f98a2SYan Zheng 24473fd0a558SYan, Zheng static noinline_for_stack 24483fd0a558SYan, Zheng int prepare_to_merge(struct reloc_control *rc, int err) 24495d4f98a2SYan Zheng { 24503fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 24510b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 24523fd0a558SYan, Zheng struct btrfs_root *reloc_root; 24535d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 24543fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 24553fd0a558SYan, Zheng u64 num_bytes = 0; 24563fd0a558SYan, Zheng int ret; 24573fd0a558SYan, Zheng 24580b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 24590b246afaSJeff Mahoney rc->merging_rsv_size += fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 24603fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated * 2; 24610b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 24627585717fSChris Mason 24633fd0a558SYan, Zheng again: 24643fd0a558SYan, Zheng if (!err) { 24653fd0a558SYan, Zheng num_bytes = rc->merging_rsv_size; 246608e007d2SMiao Xie ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes, 246708e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 24683fd0a558SYan, Zheng if (ret) 24693fd0a558SYan, Zheng err = ret; 24703fd0a558SYan, Zheng } 24713fd0a558SYan, Zheng 24727a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 24733612b495STsutomu Itoh if (IS_ERR(trans)) { 24743612b495STsutomu Itoh if (!err) 24752ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 247663f018beSNikolay Borisov num_bytes, NULL); 24773612b495STsutomu Itoh return PTR_ERR(trans); 24783612b495STsutomu Itoh } 24793fd0a558SYan, Zheng 24803fd0a558SYan, Zheng if (!err) { 24813fd0a558SYan, Zheng if (num_bytes != rc->merging_rsv_size) { 24823a45bb20SJeff Mahoney btrfs_end_transaction(trans); 24832ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 248463f018beSNikolay Borisov num_bytes, NULL); 24853fd0a558SYan, Zheng goto again; 24863fd0a558SYan, Zheng } 24873fd0a558SYan, Zheng } 24883fd0a558SYan, Zheng 24893fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 24903fd0a558SYan, Zheng 24913fd0a558SYan, Zheng while (!list_empty(&rc->reloc_roots)) { 24923fd0a558SYan, Zheng reloc_root = list_entry(rc->reloc_roots.next, 24933fd0a558SYan, Zheng struct btrfs_root, root_list); 24943fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 24953fd0a558SYan, Zheng 24960b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 24973fd0a558SYan, Zheng BUG_ON(IS_ERR(root)); 24983fd0a558SYan, Zheng BUG_ON(root->reloc_root != reloc_root); 24993fd0a558SYan, Zheng 25003fd0a558SYan, Zheng /* 25013fd0a558SYan, Zheng * set reference count to 1, so btrfs_recover_relocation 25023fd0a558SYan, Zheng * knows it should resumes merging 25033fd0a558SYan, Zheng */ 25043fd0a558SYan, Zheng if (!err) 25053fd0a558SYan, Zheng btrfs_set_root_refs(&reloc_root->root_item, 1); 25063fd0a558SYan, Zheng btrfs_update_reloc_root(trans, root); 25073fd0a558SYan, Zheng 25083fd0a558SYan, Zheng list_add(&reloc_root->root_list, &reloc_roots); 250900246528SJosef Bacik btrfs_put_root(root); 25103fd0a558SYan, Zheng } 25113fd0a558SYan, Zheng 25123fd0a558SYan, Zheng list_splice(&reloc_roots, &rc->reloc_roots); 25133fd0a558SYan, Zheng 25143fd0a558SYan, Zheng if (!err) 25153a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 25163fd0a558SYan, Zheng else 25173a45bb20SJeff Mahoney btrfs_end_transaction(trans); 25183fd0a558SYan, Zheng return err; 25193fd0a558SYan, Zheng } 25203fd0a558SYan, Zheng 25213fd0a558SYan, Zheng static noinline_for_stack 2522aca1bba6SLiu Bo void free_reloc_roots(struct list_head *list) 2523aca1bba6SLiu Bo { 2524aca1bba6SLiu Bo struct btrfs_root *reloc_root; 2525aca1bba6SLiu Bo 2526aca1bba6SLiu Bo while (!list_empty(list)) { 2527aca1bba6SLiu Bo reloc_root = list_entry(list->next, struct btrfs_root, 2528aca1bba6SLiu Bo root_list); 2529bb166d72SNaohiro Aota __del_reloc_root(reloc_root); 2530aca1bba6SLiu Bo } 2531aca1bba6SLiu Bo } 2532aca1bba6SLiu Bo 2533aca1bba6SLiu Bo static noinline_for_stack 253494404e82SDavid Sterba void merge_reloc_roots(struct reloc_control *rc) 25353fd0a558SYan, Zheng { 25360b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 25375d4f98a2SYan Zheng struct btrfs_root *root; 25385d4f98a2SYan Zheng struct btrfs_root *reloc_root; 25393fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 25403fd0a558SYan, Zheng int found = 0; 2541aca1bba6SLiu Bo int ret = 0; 25423fd0a558SYan, Zheng again: 25433fd0a558SYan, Zheng root = rc->extent_root; 25447585717fSChris Mason 25457585717fSChris Mason /* 25467585717fSChris Mason * this serializes us with btrfs_record_root_in_transaction, 25477585717fSChris Mason * we have to make sure nobody is in the middle of 25487585717fSChris Mason * adding their roots to the list while we are 25497585717fSChris Mason * doing this splice 25507585717fSChris Mason */ 25510b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 25523fd0a558SYan, Zheng list_splice_init(&rc->reloc_roots, &reloc_roots); 25530b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 25545d4f98a2SYan Zheng 25553fd0a558SYan, Zheng while (!list_empty(&reloc_roots)) { 25563fd0a558SYan, Zheng found = 1; 25573fd0a558SYan, Zheng reloc_root = list_entry(reloc_roots.next, 25583fd0a558SYan, Zheng struct btrfs_root, root_list); 25595d4f98a2SYan Zheng 25605d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 25610b246afaSJeff Mahoney root = read_fs_root(fs_info, 25625d4f98a2SYan Zheng reloc_root->root_key.offset); 25635d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 25645d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 25655d4f98a2SYan Zheng 25663fd0a558SYan, Zheng ret = merge_reloc_root(rc, root); 256700246528SJosef Bacik btrfs_put_root(root); 2568b37b39cdSJosef Bacik if (ret) { 256925e293c2SWang Shilong if (list_empty(&reloc_root->root_list)) 257025e293c2SWang Shilong list_add_tail(&reloc_root->root_list, 257125e293c2SWang Shilong &reloc_roots); 2572aca1bba6SLiu Bo goto out; 2573b37b39cdSJosef Bacik } 25743fd0a558SYan, Zheng } else { 25753fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 257630d40577SQu Wenruo /* Don't forget to queue this reloc root for cleanup */ 257730d40577SQu Wenruo list_add_tail(&reloc_root->reloc_dirty_list, 257830d40577SQu Wenruo &rc->dirty_subvol_roots); 25793fd0a558SYan, Zheng } 25805d4f98a2SYan Zheng } 25815d4f98a2SYan Zheng 25823fd0a558SYan, Zheng if (found) { 25833fd0a558SYan, Zheng found = 0; 25843fd0a558SYan, Zheng goto again; 25855d4f98a2SYan Zheng } 2586aca1bba6SLiu Bo out: 2587aca1bba6SLiu Bo if (ret) { 25880b246afaSJeff Mahoney btrfs_handle_fs_error(fs_info, ret, NULL); 2589aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 2590aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 2591467bb1d2SWang Shilong 2592467bb1d2SWang Shilong /* new reloc root may be added */ 25930b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 2594467bb1d2SWang Shilong list_splice_init(&rc->reloc_roots, &reloc_roots); 25950b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 2596467bb1d2SWang Shilong if (!list_empty(&reloc_roots)) 2597467bb1d2SWang Shilong free_reloc_roots(&reloc_roots); 2598aca1bba6SLiu Bo } 2599aca1bba6SLiu Bo 26007b7b7431SJosef Bacik /* 26017b7b7431SJosef Bacik * We used to have 26027b7b7431SJosef Bacik * 26037b7b7431SJosef Bacik * BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); 26047b7b7431SJosef Bacik * 26057b7b7431SJosef Bacik * here, but it's wrong. If we fail to start the transaction in 26067b7b7431SJosef Bacik * prepare_to_merge() we will have only 0 ref reloc roots, none of which 26077b7b7431SJosef Bacik * have actually been removed from the reloc_root_tree rb tree. This is 26087b7b7431SJosef Bacik * fine because we're bailing here, and we hold a reference on the root 26097b7b7431SJosef Bacik * for the list that holds it, so these roots will be cleaned up when we 26107b7b7431SJosef Bacik * do the reloc_dirty_list afterwards. Meanwhile the root->reloc_root 26117b7b7431SJosef Bacik * will be cleaned up on unmount. 26127b7b7431SJosef Bacik * 26137b7b7431SJosef Bacik * The remaining nodes will be cleaned up by free_reloc_control. 26147b7b7431SJosef Bacik */ 26155d4f98a2SYan Zheng } 26165d4f98a2SYan Zheng 26175d4f98a2SYan Zheng static void free_block_list(struct rb_root *blocks) 26185d4f98a2SYan Zheng { 26195d4f98a2SYan Zheng struct tree_block *block; 26205d4f98a2SYan Zheng struct rb_node *rb_node; 26215d4f98a2SYan Zheng while ((rb_node = rb_first(blocks))) { 26225d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 26235d4f98a2SYan Zheng rb_erase(rb_node, blocks); 26245d4f98a2SYan Zheng kfree(block); 26255d4f98a2SYan Zheng } 26265d4f98a2SYan Zheng } 26275d4f98a2SYan Zheng 26285d4f98a2SYan Zheng static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, 26295d4f98a2SYan Zheng struct btrfs_root *reloc_root) 26305d4f98a2SYan Zheng { 26310b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = reloc_root->fs_info; 26325d4f98a2SYan Zheng struct btrfs_root *root; 2633442b1ac5SJosef Bacik int ret; 26345d4f98a2SYan Zheng 26355d4f98a2SYan Zheng if (reloc_root->last_trans == trans->transid) 26365d4f98a2SYan Zheng return 0; 26375d4f98a2SYan Zheng 26380b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 26395d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 26405d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 2641442b1ac5SJosef Bacik ret = btrfs_record_root_in_trans(trans, root); 264200246528SJosef Bacik btrfs_put_root(root); 26435d4f98a2SYan Zheng 2644442b1ac5SJosef Bacik return ret; 26455d4f98a2SYan Zheng } 26465d4f98a2SYan Zheng 26473fd0a558SYan, Zheng static noinline_for_stack 26483fd0a558SYan, Zheng struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, 26493fd0a558SYan, Zheng struct reloc_control *rc, 26505d4f98a2SYan Zheng struct backref_node *node, 2651dc4103f9SWang Shilong struct backref_edge *edges[]) 26525d4f98a2SYan Zheng { 26535d4f98a2SYan Zheng struct backref_node *next; 26545d4f98a2SYan Zheng struct btrfs_root *root; 26553fd0a558SYan, Zheng int index = 0; 26563fd0a558SYan, Zheng 26575d4f98a2SYan Zheng next = node; 26585d4f98a2SYan Zheng while (1) { 26595d4f98a2SYan Zheng cond_resched(); 26605d4f98a2SYan Zheng next = walk_up_backref(next, edges, &index); 26615d4f98a2SYan Zheng root = next->root; 26623fd0a558SYan, Zheng BUG_ON(!root); 266327cdeb70SMiao Xie BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS, &root->state)); 26645d4f98a2SYan Zheng 26655d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { 26665d4f98a2SYan Zheng record_reloc_root_in_trans(trans, root); 26675d4f98a2SYan Zheng break; 26685d4f98a2SYan Zheng } 26695d4f98a2SYan Zheng 26705d4f98a2SYan Zheng btrfs_record_root_in_trans(trans, root); 26713fd0a558SYan, Zheng root = root->reloc_root; 26723fd0a558SYan, Zheng 26733fd0a558SYan, Zheng if (next->new_bytenr != root->node->start) { 26743fd0a558SYan, Zheng BUG_ON(next->new_bytenr); 26753fd0a558SYan, Zheng BUG_ON(!list_empty(&next->list)); 26763fd0a558SYan, Zheng next->new_bytenr = root->node->start; 267700246528SJosef Bacik btrfs_put_root(next->root); 267800246528SJosef Bacik next->root = btrfs_grab_root(root); 26790b530bc5SJosef Bacik ASSERT(next->root); 26803fd0a558SYan, Zheng list_add_tail(&next->list, 26813fd0a558SYan, Zheng &rc->backref_cache.changed); 26823fd0a558SYan, Zheng __mark_block_processed(rc, next); 26835d4f98a2SYan Zheng break; 26845d4f98a2SYan Zheng } 26855d4f98a2SYan Zheng 26863fd0a558SYan, Zheng WARN_ON(1); 26875d4f98a2SYan Zheng root = NULL; 26885d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 26895d4f98a2SYan Zheng if (!next || next->level <= node->level) 26905d4f98a2SYan Zheng break; 26915d4f98a2SYan Zheng } 26923fd0a558SYan, Zheng if (!root) 26933fd0a558SYan, Zheng return NULL; 26945d4f98a2SYan Zheng 26953fd0a558SYan, Zheng next = node; 26963fd0a558SYan, Zheng /* setup backref node path for btrfs_reloc_cow_block */ 26973fd0a558SYan, Zheng while (1) { 26983fd0a558SYan, Zheng rc->backref_cache.path[next->level] = next; 26993fd0a558SYan, Zheng if (--index < 0) 27003fd0a558SYan, Zheng break; 27013fd0a558SYan, Zheng next = edges[index]->node[UPPER]; 27023fd0a558SYan, Zheng } 27035d4f98a2SYan Zheng return root; 27045d4f98a2SYan Zheng } 27055d4f98a2SYan Zheng 27063fd0a558SYan, Zheng /* 27073fd0a558SYan, Zheng * select a tree root for relocation. return NULL if the block 27083fd0a558SYan, Zheng * is reference counted. we should use do_relocation() in this 27093fd0a558SYan, Zheng * case. return a tree root pointer if the block isn't reference 27103fd0a558SYan, Zheng * counted. return -ENOENT if the block is root of reloc tree. 27113fd0a558SYan, Zheng */ 27125d4f98a2SYan Zheng static noinline_for_stack 2713147d256eSZhaolei struct btrfs_root *select_one_root(struct backref_node *node) 27145d4f98a2SYan Zheng { 27153fd0a558SYan, Zheng struct backref_node *next; 27163fd0a558SYan, Zheng struct btrfs_root *root; 27173fd0a558SYan, Zheng struct btrfs_root *fs_root = NULL; 27185d4f98a2SYan Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 27193fd0a558SYan, Zheng int index = 0; 27203fd0a558SYan, Zheng 27213fd0a558SYan, Zheng next = node; 27223fd0a558SYan, Zheng while (1) { 27233fd0a558SYan, Zheng cond_resched(); 27243fd0a558SYan, Zheng next = walk_up_backref(next, edges, &index); 27253fd0a558SYan, Zheng root = next->root; 27263fd0a558SYan, Zheng BUG_ON(!root); 27273fd0a558SYan, Zheng 272825985edcSLucas De Marchi /* no other choice for non-references counted tree */ 272927cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 27303fd0a558SYan, Zheng return root; 27313fd0a558SYan, Zheng 27323fd0a558SYan, Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) 27333fd0a558SYan, Zheng fs_root = root; 27343fd0a558SYan, Zheng 27353fd0a558SYan, Zheng if (next != node) 27363fd0a558SYan, Zheng return NULL; 27373fd0a558SYan, Zheng 27383fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 27393fd0a558SYan, Zheng if (!next || next->level <= node->level) 27403fd0a558SYan, Zheng break; 27413fd0a558SYan, Zheng } 27423fd0a558SYan, Zheng 27433fd0a558SYan, Zheng if (!fs_root) 27443fd0a558SYan, Zheng return ERR_PTR(-ENOENT); 27453fd0a558SYan, Zheng return fs_root; 27465d4f98a2SYan Zheng } 27475d4f98a2SYan Zheng 27485d4f98a2SYan Zheng static noinline_for_stack 27493fd0a558SYan, Zheng u64 calcu_metadata_size(struct reloc_control *rc, 27503fd0a558SYan, Zheng struct backref_node *node, int reserve) 27515d4f98a2SYan Zheng { 27520b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 27533fd0a558SYan, Zheng struct backref_node *next = node; 27543fd0a558SYan, Zheng struct backref_edge *edge; 27553fd0a558SYan, Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 27563fd0a558SYan, Zheng u64 num_bytes = 0; 27573fd0a558SYan, Zheng int index = 0; 27585d4f98a2SYan Zheng 27593fd0a558SYan, Zheng BUG_ON(reserve && node->processed); 27603fd0a558SYan, Zheng 27613fd0a558SYan, Zheng while (next) { 27623fd0a558SYan, Zheng cond_resched(); 27635d4f98a2SYan Zheng while (1) { 27643fd0a558SYan, Zheng if (next->processed && (reserve || next != node)) 27655d4f98a2SYan Zheng break; 27665d4f98a2SYan Zheng 27670b246afaSJeff Mahoney num_bytes += fs_info->nodesize; 27683fd0a558SYan, Zheng 27693fd0a558SYan, Zheng if (list_empty(&next->upper)) 27703fd0a558SYan, Zheng break; 27713fd0a558SYan, Zheng 27723fd0a558SYan, Zheng edge = list_entry(next->upper.next, 27733fd0a558SYan, Zheng struct backref_edge, list[LOWER]); 27743fd0a558SYan, Zheng edges[index++] = edge; 27753fd0a558SYan, Zheng next = edge->node[UPPER]; 27765d4f98a2SYan Zheng } 27773fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 27783fd0a558SYan, Zheng } 27793fd0a558SYan, Zheng return num_bytes; 27803fd0a558SYan, Zheng } 27813fd0a558SYan, Zheng 27823fd0a558SYan, Zheng static int reserve_metadata_space(struct btrfs_trans_handle *trans, 27833fd0a558SYan, Zheng struct reloc_control *rc, 27843fd0a558SYan, Zheng struct backref_node *node) 27853fd0a558SYan, Zheng { 27863fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 2787da17066cSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 27883fd0a558SYan, Zheng u64 num_bytes; 27893fd0a558SYan, Zheng int ret; 27900647bf56SWang Shilong u64 tmp; 27913fd0a558SYan, Zheng 27923fd0a558SYan, Zheng num_bytes = calcu_metadata_size(rc, node, 1) * 2; 27933fd0a558SYan, Zheng 27943fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 27950647bf56SWang Shilong rc->reserved_bytes += num_bytes; 27968ca17f0fSJosef Bacik 27978ca17f0fSJosef Bacik /* 27988ca17f0fSJosef Bacik * We are under a transaction here so we can only do limited flushing. 27998ca17f0fSJosef Bacik * If we get an enospc just kick back -EAGAIN so we know to drop the 28008ca17f0fSJosef Bacik * transaction and try to refill when we can flush all the things. 28018ca17f0fSJosef Bacik */ 28020647bf56SWang Shilong ret = btrfs_block_rsv_refill(root, rc->block_rsv, num_bytes, 28038ca17f0fSJosef Bacik BTRFS_RESERVE_FLUSH_LIMIT); 28043fd0a558SYan, Zheng if (ret) { 2805da17066cSJeff Mahoney tmp = fs_info->nodesize * RELOCATION_RESERVED_NODES; 28060647bf56SWang Shilong while (tmp <= rc->reserved_bytes) 28070647bf56SWang Shilong tmp <<= 1; 28080647bf56SWang Shilong /* 28090647bf56SWang Shilong * only one thread can access block_rsv at this point, 28100647bf56SWang Shilong * so we don't need hold lock to protect block_rsv. 28110647bf56SWang Shilong * we expand more reservation size here to allow enough 281252042d8eSAndrea Gelmini * space for relocation and we will return earlier in 28130647bf56SWang Shilong * enospc case. 28140647bf56SWang Shilong */ 2815da17066cSJeff Mahoney rc->block_rsv->size = tmp + fs_info->nodesize * 28160647bf56SWang Shilong RELOCATION_RESERVED_NODES; 28178ca17f0fSJosef Bacik return -EAGAIN; 28183fd0a558SYan, Zheng } 28193fd0a558SYan, Zheng 28203fd0a558SYan, Zheng return 0; 28213fd0a558SYan, Zheng } 28223fd0a558SYan, Zheng 28235d4f98a2SYan Zheng /* 28245d4f98a2SYan Zheng * relocate a block tree, and then update pointers in upper level 28255d4f98a2SYan Zheng * blocks that reference the block to point to the new location. 28265d4f98a2SYan Zheng * 28275d4f98a2SYan Zheng * if called by link_to_upper, the block has already been relocated. 28285d4f98a2SYan Zheng * in that case this function just updates pointers. 28295d4f98a2SYan Zheng */ 28305d4f98a2SYan Zheng static int do_relocation(struct btrfs_trans_handle *trans, 28313fd0a558SYan, Zheng struct reloc_control *rc, 28325d4f98a2SYan Zheng struct backref_node *node, 28335d4f98a2SYan Zheng struct btrfs_key *key, 28345d4f98a2SYan Zheng struct btrfs_path *path, int lowest) 28355d4f98a2SYan Zheng { 28362ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 28375d4f98a2SYan Zheng struct backref_node *upper; 28385d4f98a2SYan Zheng struct backref_edge *edge; 28395d4f98a2SYan Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 28405d4f98a2SYan Zheng struct btrfs_root *root; 28415d4f98a2SYan Zheng struct extent_buffer *eb; 28425d4f98a2SYan Zheng u32 blocksize; 28435d4f98a2SYan Zheng u64 bytenr; 28445d4f98a2SYan Zheng u64 generation; 28455d4f98a2SYan Zheng int slot; 28465d4f98a2SYan Zheng int ret; 28475d4f98a2SYan Zheng int err = 0; 28485d4f98a2SYan Zheng 28495d4f98a2SYan Zheng BUG_ON(lowest && node->eb); 28505d4f98a2SYan Zheng 28515d4f98a2SYan Zheng path->lowest_level = node->level + 1; 28523fd0a558SYan, Zheng rc->backref_cache.path[node->level] = node; 28535d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) { 2854581c1760SQu Wenruo struct btrfs_key first_key; 285582fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 2856581c1760SQu Wenruo 28575d4f98a2SYan Zheng cond_resched(); 28585d4f98a2SYan Zheng 28595d4f98a2SYan Zheng upper = edge->node[UPPER]; 2860dc4103f9SWang Shilong root = select_reloc_root(trans, rc, upper, edges); 28613fd0a558SYan, Zheng BUG_ON(!root); 28625d4f98a2SYan Zheng 28633fd0a558SYan, Zheng if (upper->eb && !upper->locked) { 28643fd0a558SYan, Zheng if (!lowest) { 28653fd0a558SYan, Zheng ret = btrfs_bin_search(upper->eb, key, 28663fd0a558SYan, Zheng upper->level, &slot); 2867cbca7d59SFilipe Manana if (ret < 0) { 2868cbca7d59SFilipe Manana err = ret; 2869cbca7d59SFilipe Manana goto next; 2870cbca7d59SFilipe Manana } 28713fd0a558SYan, Zheng BUG_ON(ret); 28723fd0a558SYan, Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 28733fd0a558SYan, Zheng if (node->eb->start == bytenr) 28743fd0a558SYan, Zheng goto next; 28753fd0a558SYan, Zheng } 28765d4f98a2SYan Zheng drop_node_buffer(upper); 28773fd0a558SYan, Zheng } 28785d4f98a2SYan Zheng 28795d4f98a2SYan Zheng if (!upper->eb) { 28805d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 28813561b9dbSLiu Bo if (ret) { 28823561b9dbSLiu Bo if (ret < 0) 28835d4f98a2SYan Zheng err = ret; 28843561b9dbSLiu Bo else 28853561b9dbSLiu Bo err = -ENOENT; 28863561b9dbSLiu Bo 28873561b9dbSLiu Bo btrfs_release_path(path); 28885d4f98a2SYan Zheng break; 28895d4f98a2SYan Zheng } 28905d4f98a2SYan Zheng 28913fd0a558SYan, Zheng if (!upper->eb) { 28923fd0a558SYan, Zheng upper->eb = path->nodes[upper->level]; 28933fd0a558SYan, Zheng path->nodes[upper->level] = NULL; 28943fd0a558SYan, Zheng } else { 28953fd0a558SYan, Zheng BUG_ON(upper->eb != path->nodes[upper->level]); 28963fd0a558SYan, Zheng } 28973fd0a558SYan, Zheng 28983fd0a558SYan, Zheng upper->locked = 1; 28993fd0a558SYan, Zheng path->locks[upper->level] = 0; 29003fd0a558SYan, Zheng 29015d4f98a2SYan Zheng slot = path->slots[upper->level]; 2902b3b4aa74SDavid Sterba btrfs_release_path(path); 29035d4f98a2SYan Zheng } else { 29045d4f98a2SYan Zheng ret = btrfs_bin_search(upper->eb, key, upper->level, 29055d4f98a2SYan Zheng &slot); 2906cbca7d59SFilipe Manana if (ret < 0) { 2907cbca7d59SFilipe Manana err = ret; 2908cbca7d59SFilipe Manana goto next; 2909cbca7d59SFilipe Manana } 29105d4f98a2SYan Zheng BUG_ON(ret); 29115d4f98a2SYan Zheng } 29125d4f98a2SYan Zheng 29135d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 29143fd0a558SYan, Zheng if (lowest) { 29154547f4d8SLiu Bo if (bytenr != node->bytenr) { 29164547f4d8SLiu Bo btrfs_err(root->fs_info, 29174547f4d8SLiu Bo "lowest leaf/node mismatch: bytenr %llu node->bytenr %llu slot %d upper %llu", 29184547f4d8SLiu Bo bytenr, node->bytenr, slot, 29194547f4d8SLiu Bo upper->eb->start); 29204547f4d8SLiu Bo err = -EIO; 29214547f4d8SLiu Bo goto next; 29224547f4d8SLiu Bo } 29235d4f98a2SYan Zheng } else { 29243fd0a558SYan, Zheng if (node->eb->start == bytenr) 29253fd0a558SYan, Zheng goto next; 29265d4f98a2SYan Zheng } 29275d4f98a2SYan Zheng 2928da17066cSJeff Mahoney blocksize = root->fs_info->nodesize; 29295d4f98a2SYan Zheng generation = btrfs_node_ptr_generation(upper->eb, slot); 2930581c1760SQu Wenruo btrfs_node_key_to_cpu(upper->eb, &first_key, slot); 2931581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, generation, 2932581c1760SQu Wenruo upper->level - 1, &first_key); 293364c043deSLiu Bo if (IS_ERR(eb)) { 293464c043deSLiu Bo err = PTR_ERR(eb); 293564c043deSLiu Bo goto next; 293664c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2937416bc658SJosef Bacik free_extent_buffer(eb); 293897d9a8a4STsutomu Itoh err = -EIO; 293997d9a8a4STsutomu Itoh goto next; 294097d9a8a4STsutomu Itoh } 29415d4f98a2SYan Zheng btrfs_tree_lock(eb); 29428bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 29435d4f98a2SYan Zheng 29445d4f98a2SYan Zheng if (!node->eb) { 29455d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, eb, upper->eb, 29465d4f98a2SYan Zheng slot, &eb); 29473fd0a558SYan, Zheng btrfs_tree_unlock(eb); 29483fd0a558SYan, Zheng free_extent_buffer(eb); 29495d4f98a2SYan Zheng if (ret < 0) { 29505d4f98a2SYan Zheng err = ret; 29513fd0a558SYan, Zheng goto next; 29525d4f98a2SYan Zheng } 29533fd0a558SYan, Zheng BUG_ON(node->eb != eb); 29545d4f98a2SYan Zheng } else { 29555d4f98a2SYan Zheng btrfs_set_node_blockptr(upper->eb, slot, 29565d4f98a2SYan Zheng node->eb->start); 29575d4f98a2SYan Zheng btrfs_set_node_ptr_generation(upper->eb, slot, 29585d4f98a2SYan Zheng trans->transid); 29595d4f98a2SYan Zheng btrfs_mark_buffer_dirty(upper->eb); 29605d4f98a2SYan Zheng 296182fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, 29625d4f98a2SYan Zheng node->eb->start, blocksize, 296382fa113fSQu Wenruo upper->eb->start); 296482fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 296582fa113fSQu Wenruo btrfs_init_tree_ref(&ref, node->level, 296682fa113fSQu Wenruo btrfs_header_owner(upper->eb)); 296782fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 29685d4f98a2SYan Zheng BUG_ON(ret); 29695d4f98a2SYan Zheng 29705d4f98a2SYan Zheng ret = btrfs_drop_subtree(trans, root, eb, upper->eb); 29715d4f98a2SYan Zheng BUG_ON(ret); 29725d4f98a2SYan Zheng } 29733fd0a558SYan, Zheng next: 29743fd0a558SYan, Zheng if (!upper->pending) 29753fd0a558SYan, Zheng drop_node_buffer(upper); 29763fd0a558SYan, Zheng else 29773fd0a558SYan, Zheng unlock_node_buffer(upper); 29783fd0a558SYan, Zheng if (err) 29793fd0a558SYan, Zheng break; 29805d4f98a2SYan Zheng } 29813fd0a558SYan, Zheng 29823fd0a558SYan, Zheng if (!err && node->pending) { 29833fd0a558SYan, Zheng drop_node_buffer(node); 29843fd0a558SYan, Zheng list_move_tail(&node->list, &rc->backref_cache.changed); 29853fd0a558SYan, Zheng node->pending = 0; 29865d4f98a2SYan Zheng } 29873fd0a558SYan, Zheng 29885d4f98a2SYan Zheng path->lowest_level = 0; 29893fd0a558SYan, Zheng BUG_ON(err == -ENOSPC); 29905d4f98a2SYan Zheng return err; 29915d4f98a2SYan Zheng } 29925d4f98a2SYan Zheng 29935d4f98a2SYan Zheng static int link_to_upper(struct btrfs_trans_handle *trans, 29943fd0a558SYan, Zheng struct reloc_control *rc, 29955d4f98a2SYan Zheng struct backref_node *node, 29965d4f98a2SYan Zheng struct btrfs_path *path) 29975d4f98a2SYan Zheng { 29985d4f98a2SYan Zheng struct btrfs_key key; 29995d4f98a2SYan Zheng 30005d4f98a2SYan Zheng btrfs_node_key_to_cpu(node->eb, &key, 0); 30013fd0a558SYan, Zheng return do_relocation(trans, rc, node, &key, path, 0); 30025d4f98a2SYan Zheng } 30035d4f98a2SYan Zheng 30045d4f98a2SYan Zheng static int finish_pending_nodes(struct btrfs_trans_handle *trans, 30053fd0a558SYan, Zheng struct reloc_control *rc, 30063fd0a558SYan, Zheng struct btrfs_path *path, int err) 30075d4f98a2SYan Zheng { 30083fd0a558SYan, Zheng LIST_HEAD(list); 30093fd0a558SYan, Zheng struct backref_cache *cache = &rc->backref_cache; 30105d4f98a2SYan Zheng struct backref_node *node; 30115d4f98a2SYan Zheng int level; 30125d4f98a2SYan Zheng int ret; 30135d4f98a2SYan Zheng 30145d4f98a2SYan Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 30155d4f98a2SYan Zheng while (!list_empty(&cache->pending[level])) { 30165d4f98a2SYan Zheng node = list_entry(cache->pending[level].next, 30173fd0a558SYan, Zheng struct backref_node, list); 30183fd0a558SYan, Zheng list_move_tail(&node->list, &list); 30193fd0a558SYan, Zheng BUG_ON(!node->pending); 30205d4f98a2SYan Zheng 30213fd0a558SYan, Zheng if (!err) { 30223fd0a558SYan, Zheng ret = link_to_upper(trans, rc, node, path); 30235d4f98a2SYan Zheng if (ret < 0) 30245d4f98a2SYan Zheng err = ret; 30255d4f98a2SYan Zheng } 30265d4f98a2SYan Zheng } 30273fd0a558SYan, Zheng list_splice_init(&list, &cache->pending[level]); 30283fd0a558SYan, Zheng } 30295d4f98a2SYan Zheng return err; 30305d4f98a2SYan Zheng } 30315d4f98a2SYan Zheng 30325d4f98a2SYan Zheng static void mark_block_processed(struct reloc_control *rc, 30333fd0a558SYan, Zheng u64 bytenr, u32 blocksize) 30343fd0a558SYan, Zheng { 30353fd0a558SYan, Zheng set_extent_bits(&rc->processed_blocks, bytenr, bytenr + blocksize - 1, 3036ceeb0ae7SDavid Sterba EXTENT_DIRTY); 30373fd0a558SYan, Zheng } 30383fd0a558SYan, Zheng 30393fd0a558SYan, Zheng static void __mark_block_processed(struct reloc_control *rc, 30405d4f98a2SYan Zheng struct backref_node *node) 30415d4f98a2SYan Zheng { 30425d4f98a2SYan Zheng u32 blocksize; 30435d4f98a2SYan Zheng if (node->level == 0 || 30445d4f98a2SYan Zheng in_block_group(node->bytenr, rc->block_group)) { 3045da17066cSJeff Mahoney blocksize = rc->extent_root->fs_info->nodesize; 30463fd0a558SYan, Zheng mark_block_processed(rc, node->bytenr, blocksize); 30475d4f98a2SYan Zheng } 30485d4f98a2SYan Zheng node->processed = 1; 30495d4f98a2SYan Zheng } 30505d4f98a2SYan Zheng 30515d4f98a2SYan Zheng /* 30525d4f98a2SYan Zheng * mark a block and all blocks directly/indirectly reference the block 30535d4f98a2SYan Zheng * as processed. 30545d4f98a2SYan Zheng */ 30555d4f98a2SYan Zheng static void update_processed_blocks(struct reloc_control *rc, 30565d4f98a2SYan Zheng struct backref_node *node) 30575d4f98a2SYan Zheng { 30585d4f98a2SYan Zheng struct backref_node *next = node; 30595d4f98a2SYan Zheng struct backref_edge *edge; 30605d4f98a2SYan Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 30615d4f98a2SYan Zheng int index = 0; 30625d4f98a2SYan Zheng 30635d4f98a2SYan Zheng while (next) { 30645d4f98a2SYan Zheng cond_resched(); 30655d4f98a2SYan Zheng while (1) { 30665d4f98a2SYan Zheng if (next->processed) 30675d4f98a2SYan Zheng break; 30685d4f98a2SYan Zheng 30693fd0a558SYan, Zheng __mark_block_processed(rc, next); 30705d4f98a2SYan Zheng 30715d4f98a2SYan Zheng if (list_empty(&next->upper)) 30725d4f98a2SYan Zheng break; 30735d4f98a2SYan Zheng 30745d4f98a2SYan Zheng edge = list_entry(next->upper.next, 30755d4f98a2SYan Zheng struct backref_edge, list[LOWER]); 30765d4f98a2SYan Zheng edges[index++] = edge; 30775d4f98a2SYan Zheng next = edge->node[UPPER]; 30785d4f98a2SYan Zheng } 30795d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 30805d4f98a2SYan Zheng } 30815d4f98a2SYan Zheng } 30825d4f98a2SYan Zheng 30837476dfdaSDavid Sterba static int tree_block_processed(u64 bytenr, struct reloc_control *rc) 30845d4f98a2SYan Zheng { 3085da17066cSJeff Mahoney u32 blocksize = rc->extent_root->fs_info->nodesize; 30867476dfdaSDavid Sterba 30875d4f98a2SYan Zheng if (test_range_bit(&rc->processed_blocks, bytenr, 30889655d298SChris Mason bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) 30895d4f98a2SYan Zheng return 1; 30905d4f98a2SYan Zheng return 0; 30915d4f98a2SYan Zheng } 30925d4f98a2SYan Zheng 30932ff7e61eSJeff Mahoney static int get_tree_block_key(struct btrfs_fs_info *fs_info, 30945d4f98a2SYan Zheng struct tree_block *block) 30955d4f98a2SYan Zheng { 30965d4f98a2SYan Zheng struct extent_buffer *eb; 30975d4f98a2SYan Zheng 3098581c1760SQu Wenruo eb = read_tree_block(fs_info, block->bytenr, block->key.offset, 3099581c1760SQu Wenruo block->level, NULL); 310064c043deSLiu Bo if (IS_ERR(eb)) { 310164c043deSLiu Bo return PTR_ERR(eb); 310264c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 3103416bc658SJosef Bacik free_extent_buffer(eb); 3104416bc658SJosef Bacik return -EIO; 3105416bc658SJosef Bacik } 31065d4f98a2SYan Zheng if (block->level == 0) 31075d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &block->key, 0); 31085d4f98a2SYan Zheng else 31095d4f98a2SYan Zheng btrfs_node_key_to_cpu(eb, &block->key, 0); 31105d4f98a2SYan Zheng free_extent_buffer(eb); 31115d4f98a2SYan Zheng block->key_ready = 1; 31125d4f98a2SYan Zheng return 0; 31135d4f98a2SYan Zheng } 31145d4f98a2SYan Zheng 31155d4f98a2SYan Zheng /* 31165d4f98a2SYan Zheng * helper function to relocate a tree block 31175d4f98a2SYan Zheng */ 31185d4f98a2SYan Zheng static int relocate_tree_block(struct btrfs_trans_handle *trans, 31195d4f98a2SYan Zheng struct reloc_control *rc, 31205d4f98a2SYan Zheng struct backref_node *node, 31215d4f98a2SYan Zheng struct btrfs_key *key, 31225d4f98a2SYan Zheng struct btrfs_path *path) 31235d4f98a2SYan Zheng { 31245d4f98a2SYan Zheng struct btrfs_root *root; 31253fd0a558SYan, Zheng int ret = 0; 31265d4f98a2SYan Zheng 31273fd0a558SYan, Zheng if (!node) 31285d4f98a2SYan Zheng return 0; 31293fd0a558SYan, Zheng 31305f6b2e5cSJosef Bacik /* 31315f6b2e5cSJosef Bacik * If we fail here we want to drop our backref_node because we are going 31325f6b2e5cSJosef Bacik * to start over and regenerate the tree for it. 31335f6b2e5cSJosef Bacik */ 31345f6b2e5cSJosef Bacik ret = reserve_metadata_space(trans, rc, node); 31355f6b2e5cSJosef Bacik if (ret) 31365f6b2e5cSJosef Bacik goto out; 31375f6b2e5cSJosef Bacik 31383fd0a558SYan, Zheng BUG_ON(node->processed); 3139147d256eSZhaolei root = select_one_root(node); 31403fd0a558SYan, Zheng if (root == ERR_PTR(-ENOENT)) { 31413fd0a558SYan, Zheng update_processed_blocks(rc, node); 31423fd0a558SYan, Zheng goto out; 31435d4f98a2SYan Zheng } 31445d4f98a2SYan Zheng 31453fd0a558SYan, Zheng if (root) { 314627cdeb70SMiao Xie if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) { 31473fd0a558SYan, Zheng BUG_ON(node->new_bytenr); 31483fd0a558SYan, Zheng BUG_ON(!list_empty(&node->list)); 31493fd0a558SYan, Zheng btrfs_record_root_in_trans(trans, root); 31503fd0a558SYan, Zheng root = root->reloc_root; 31513fd0a558SYan, Zheng node->new_bytenr = root->node->start; 315200246528SJosef Bacik btrfs_put_root(node->root); 315300246528SJosef Bacik node->root = btrfs_grab_root(root); 31540b530bc5SJosef Bacik ASSERT(node->root); 31553fd0a558SYan, Zheng list_add_tail(&node->list, &rc->backref_cache.changed); 31563fd0a558SYan, Zheng } else { 31575d4f98a2SYan Zheng path->lowest_level = node->level; 31585d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 3159b3b4aa74SDavid Sterba btrfs_release_path(path); 31603fd0a558SYan, Zheng if (ret > 0) 31615d4f98a2SYan Zheng ret = 0; 31623fd0a558SYan, Zheng } 31633fd0a558SYan, Zheng if (!ret) 31643fd0a558SYan, Zheng update_processed_blocks(rc, node); 31653fd0a558SYan, Zheng } else { 31663fd0a558SYan, Zheng ret = do_relocation(trans, rc, node, key, path, 1); 31673fd0a558SYan, Zheng } 31685d4f98a2SYan Zheng out: 31690647bf56SWang Shilong if (ret || node->level == 0 || node->cowonly) 31703fd0a558SYan, Zheng remove_backref_node(&rc->backref_cache, node); 31715d4f98a2SYan Zheng return ret; 31725d4f98a2SYan Zheng } 31735d4f98a2SYan Zheng 31745d4f98a2SYan Zheng /* 31755d4f98a2SYan Zheng * relocate a list of blocks 31765d4f98a2SYan Zheng */ 31775d4f98a2SYan Zheng static noinline_for_stack 31785d4f98a2SYan Zheng int relocate_tree_blocks(struct btrfs_trans_handle *trans, 31795d4f98a2SYan Zheng struct reloc_control *rc, struct rb_root *blocks) 31805d4f98a2SYan Zheng { 31812ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 31825d4f98a2SYan Zheng struct backref_node *node; 31835d4f98a2SYan Zheng struct btrfs_path *path; 31845d4f98a2SYan Zheng struct tree_block *block; 318598ff7b94SQu Wenruo struct tree_block *next; 31865d4f98a2SYan Zheng int ret; 31875d4f98a2SYan Zheng int err = 0; 31885d4f98a2SYan Zheng 31895d4f98a2SYan Zheng path = btrfs_alloc_path(); 3190e1a12670SLiu Bo if (!path) { 3191e1a12670SLiu Bo err = -ENOMEM; 319234c2b290SDavid Sterba goto out_free_blocks; 3193e1a12670SLiu Bo } 31945d4f98a2SYan Zheng 319598ff7b94SQu Wenruo /* Kick in readahead for tree blocks with missing keys */ 319698ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 31975d4f98a2SYan Zheng if (!block->key_ready) 31982ff7e61eSJeff Mahoney readahead_tree_block(fs_info, block->bytenr); 31995d4f98a2SYan Zheng } 32005d4f98a2SYan Zheng 320198ff7b94SQu Wenruo /* Get first keys */ 320298ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 320334c2b290SDavid Sterba if (!block->key_ready) { 32042ff7e61eSJeff Mahoney err = get_tree_block_key(fs_info, block); 320534c2b290SDavid Sterba if (err) 320634c2b290SDavid Sterba goto out_free_path; 320734c2b290SDavid Sterba } 32085d4f98a2SYan Zheng } 32095d4f98a2SYan Zheng 321098ff7b94SQu Wenruo /* Do tree relocation */ 321198ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 32123fd0a558SYan, Zheng node = build_backref_tree(rc, &block->key, 32135d4f98a2SYan Zheng block->level, block->bytenr); 32145d4f98a2SYan Zheng if (IS_ERR(node)) { 32155d4f98a2SYan Zheng err = PTR_ERR(node); 32165d4f98a2SYan Zheng goto out; 32175d4f98a2SYan Zheng } 32185d4f98a2SYan Zheng 32195d4f98a2SYan Zheng ret = relocate_tree_block(trans, rc, node, &block->key, 32205d4f98a2SYan Zheng path); 32215d4f98a2SYan Zheng if (ret < 0) { 32225d4f98a2SYan Zheng err = ret; 322350dbbb71SJosef Bacik break; 32245d4f98a2SYan Zheng } 32255d4f98a2SYan Zheng } 32265d4f98a2SYan Zheng out: 32273fd0a558SYan, Zheng err = finish_pending_nodes(trans, rc, path, err); 32285d4f98a2SYan Zheng 322934c2b290SDavid Sterba out_free_path: 32305d4f98a2SYan Zheng btrfs_free_path(path); 323134c2b290SDavid Sterba out_free_blocks: 3232e1a12670SLiu Bo free_block_list(blocks); 32335d4f98a2SYan Zheng return err; 32345d4f98a2SYan Zheng } 32355d4f98a2SYan Zheng 32365d4f98a2SYan Zheng static noinline_for_stack 3237efa56464SYan, Zheng int prealloc_file_extent_cluster(struct inode *inode, 3238efa56464SYan, Zheng struct file_extent_cluster *cluster) 3239efa56464SYan, Zheng { 3240efa56464SYan, Zheng u64 alloc_hint = 0; 3241efa56464SYan, Zheng u64 start; 3242efa56464SYan, Zheng u64 end; 3243efa56464SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 3244efa56464SYan, Zheng u64 num_bytes; 3245efa56464SYan, Zheng int nr = 0; 3246efa56464SYan, Zheng int ret = 0; 3247dcb40c19SWang Xiaoguang u64 prealloc_start = cluster->start - offset; 3248dcb40c19SWang Xiaoguang u64 prealloc_end = cluster->end - offset; 324918513091SWang Xiaoguang u64 cur_offset; 3250364ecf36SQu Wenruo struct extent_changeset *data_reserved = NULL; 3251efa56464SYan, Zheng 3252efa56464SYan, Zheng BUG_ON(cluster->start != cluster->boundary[0]); 32535955102cSAl Viro inode_lock(inode); 3254efa56464SYan, Zheng 3255364ecf36SQu Wenruo ret = btrfs_check_data_free_space(inode, &data_reserved, prealloc_start, 3256dcb40c19SWang Xiaoguang prealloc_end + 1 - prealloc_start); 3257efa56464SYan, Zheng if (ret) 3258efa56464SYan, Zheng goto out; 3259efa56464SYan, Zheng 326018513091SWang Xiaoguang cur_offset = prealloc_start; 3261efa56464SYan, Zheng while (nr < cluster->nr) { 3262efa56464SYan, Zheng start = cluster->boundary[nr] - offset; 3263efa56464SYan, Zheng if (nr + 1 < cluster->nr) 3264efa56464SYan, Zheng end = cluster->boundary[nr + 1] - 1 - offset; 3265efa56464SYan, Zheng else 3266efa56464SYan, Zheng end = cluster->end - offset; 3267efa56464SYan, Zheng 3268d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 3269efa56464SYan, Zheng num_bytes = end + 1 - start; 327018513091SWang Xiaoguang if (cur_offset < start) 3271bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3272bc42bda2SQu Wenruo cur_offset, start - cur_offset); 3273efa56464SYan, Zheng ret = btrfs_prealloc_file_range(inode, 0, start, 3274efa56464SYan, Zheng num_bytes, num_bytes, 3275efa56464SYan, Zheng end + 1, &alloc_hint); 327618513091SWang Xiaoguang cur_offset = end + 1; 3277d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 3278efa56464SYan, Zheng if (ret) 3279efa56464SYan, Zheng break; 3280efa56464SYan, Zheng nr++; 3281efa56464SYan, Zheng } 328218513091SWang Xiaoguang if (cur_offset < prealloc_end) 3283bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3284bc42bda2SQu Wenruo cur_offset, prealloc_end + 1 - cur_offset); 3285efa56464SYan, Zheng out: 32865955102cSAl Viro inode_unlock(inode); 3287364ecf36SQu Wenruo extent_changeset_free(data_reserved); 3288efa56464SYan, Zheng return ret; 3289efa56464SYan, Zheng } 3290efa56464SYan, Zheng 3291efa56464SYan, Zheng static noinline_for_stack 32920257bb82SYan, Zheng int setup_extent_mapping(struct inode *inode, u64 start, u64 end, 32930257bb82SYan, Zheng u64 block_start) 32945d4f98a2SYan Zheng { 32955d4f98a2SYan Zheng struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 32965d4f98a2SYan Zheng struct extent_map *em; 32970257bb82SYan, Zheng int ret = 0; 32985d4f98a2SYan Zheng 3299172ddd60SDavid Sterba em = alloc_extent_map(); 33000257bb82SYan, Zheng if (!em) 33010257bb82SYan, Zheng return -ENOMEM; 33020257bb82SYan, Zheng 33035d4f98a2SYan Zheng em->start = start; 33040257bb82SYan, Zheng em->len = end + 1 - start; 33050257bb82SYan, Zheng em->block_len = em->len; 33060257bb82SYan, Zheng em->block_start = block_start; 33075d4f98a2SYan Zheng set_bit(EXTENT_FLAG_PINNED, &em->flags); 33085d4f98a2SYan Zheng 3309d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 33105d4f98a2SYan Zheng while (1) { 3311890871beSChris Mason write_lock(&em_tree->lock); 331209a2a8f9SJosef Bacik ret = add_extent_mapping(em_tree, em, 0); 3313890871beSChris Mason write_unlock(&em_tree->lock); 33145d4f98a2SYan Zheng if (ret != -EEXIST) { 33155d4f98a2SYan Zheng free_extent_map(em); 33165d4f98a2SYan Zheng break; 33175d4f98a2SYan Zheng } 3318dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); 33195d4f98a2SYan Zheng } 3320d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 33210257bb82SYan, Zheng return ret; 33220257bb82SYan, Zheng } 33235d4f98a2SYan Zheng 3324726a3421SQu Wenruo /* 3325726a3421SQu Wenruo * Allow error injection to test balance cancellation 3326726a3421SQu Wenruo */ 3327726a3421SQu Wenruo int btrfs_should_cancel_balance(struct btrfs_fs_info *fs_info) 3328726a3421SQu Wenruo { 3329726a3421SQu Wenruo return atomic_read(&fs_info->balance_cancel_req); 3330726a3421SQu Wenruo } 3331726a3421SQu Wenruo ALLOW_ERROR_INJECTION(btrfs_should_cancel_balance, TRUE); 3332726a3421SQu Wenruo 33330257bb82SYan, Zheng static int relocate_file_extent_cluster(struct inode *inode, 33340257bb82SYan, Zheng struct file_extent_cluster *cluster) 33350257bb82SYan, Zheng { 33362ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 33370257bb82SYan, Zheng u64 page_start; 33380257bb82SYan, Zheng u64 page_end; 33390257bb82SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 33400257bb82SYan, Zheng unsigned long index; 33410257bb82SYan, Zheng unsigned long last_index; 33420257bb82SYan, Zheng struct page *page; 33430257bb82SYan, Zheng struct file_ra_state *ra; 33443b16a4e3SJosef Bacik gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 33450257bb82SYan, Zheng int nr = 0; 33460257bb82SYan, Zheng int ret = 0; 33470257bb82SYan, Zheng 33480257bb82SYan, Zheng if (!cluster->nr) 33490257bb82SYan, Zheng return 0; 33500257bb82SYan, Zheng 33510257bb82SYan, Zheng ra = kzalloc(sizeof(*ra), GFP_NOFS); 33520257bb82SYan, Zheng if (!ra) 33530257bb82SYan, Zheng return -ENOMEM; 33540257bb82SYan, Zheng 3355efa56464SYan, Zheng ret = prealloc_file_extent_cluster(inode, cluster); 33560257bb82SYan, Zheng if (ret) 3357efa56464SYan, Zheng goto out; 33580257bb82SYan, Zheng 33590257bb82SYan, Zheng file_ra_state_init(ra, inode->i_mapping); 33600257bb82SYan, Zheng 3361efa56464SYan, Zheng ret = setup_extent_mapping(inode, cluster->start - offset, 3362efa56464SYan, Zheng cluster->end - offset, cluster->start); 3363efa56464SYan, Zheng if (ret) 3364efa56464SYan, Zheng goto out; 3365efa56464SYan, Zheng 336609cbfeafSKirill A. Shutemov index = (cluster->start - offset) >> PAGE_SHIFT; 336709cbfeafSKirill A. Shutemov last_index = (cluster->end - offset) >> PAGE_SHIFT; 33680257bb82SYan, Zheng while (index <= last_index) { 33699f3db423SNikolay Borisov ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), 33709f3db423SNikolay Borisov PAGE_SIZE); 3371efa56464SYan, Zheng if (ret) 3372efa56464SYan, Zheng goto out; 3373efa56464SYan, Zheng 33740257bb82SYan, Zheng page = find_lock_page(inode->i_mapping, index); 33750257bb82SYan, Zheng if (!page) { 33760257bb82SYan, Zheng page_cache_sync_readahead(inode->i_mapping, 33770257bb82SYan, Zheng ra, NULL, index, 33780257bb82SYan, Zheng last_index + 1 - index); 3379a94733d0SJosef Bacik page = find_or_create_page(inode->i_mapping, index, 33803b16a4e3SJosef Bacik mask); 33810257bb82SYan, Zheng if (!page) { 3382691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 338343b18595SQu Wenruo PAGE_SIZE, true); 338444db1216SFilipe Manana btrfs_delalloc_release_extents(BTRFS_I(inode), 33858702ba93SQu Wenruo PAGE_SIZE); 33860257bb82SYan, Zheng ret = -ENOMEM; 3387efa56464SYan, Zheng goto out; 33880257bb82SYan, Zheng } 33890257bb82SYan, Zheng } 33900257bb82SYan, Zheng 33910257bb82SYan, Zheng if (PageReadahead(page)) { 33920257bb82SYan, Zheng page_cache_async_readahead(inode->i_mapping, 33930257bb82SYan, Zheng ra, NULL, page, index, 33940257bb82SYan, Zheng last_index + 1 - index); 33950257bb82SYan, Zheng } 33960257bb82SYan, Zheng 33970257bb82SYan, Zheng if (!PageUptodate(page)) { 33980257bb82SYan, Zheng btrfs_readpage(NULL, page); 33990257bb82SYan, Zheng lock_page(page); 34000257bb82SYan, Zheng if (!PageUptodate(page)) { 34010257bb82SYan, Zheng unlock_page(page); 340209cbfeafSKirill A. Shutemov put_page(page); 3403691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 340443b18595SQu Wenruo PAGE_SIZE, true); 34058b62f87bSJosef Bacik btrfs_delalloc_release_extents(BTRFS_I(inode), 34068702ba93SQu Wenruo PAGE_SIZE); 34070257bb82SYan, Zheng ret = -EIO; 3408efa56464SYan, Zheng goto out; 34090257bb82SYan, Zheng } 34100257bb82SYan, Zheng } 34110257bb82SYan, Zheng 34124eee4fa4SMiao Xie page_start = page_offset(page); 341309cbfeafSKirill A. Shutemov page_end = page_start + PAGE_SIZE - 1; 34140257bb82SYan, Zheng 3415d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end); 34160257bb82SYan, Zheng 34170257bb82SYan, Zheng set_page_extent_mapped(page); 34180257bb82SYan, Zheng 34190257bb82SYan, Zheng if (nr < cluster->nr && 34200257bb82SYan, Zheng page_start + offset == cluster->boundary[nr]) { 34210257bb82SYan, Zheng set_extent_bits(&BTRFS_I(inode)->io_tree, 34220257bb82SYan, Zheng page_start, page_end, 3423ceeb0ae7SDavid Sterba EXTENT_BOUNDARY); 34240257bb82SYan, Zheng nr++; 34250257bb82SYan, Zheng } 34260257bb82SYan, Zheng 3427765f3cebSNikolay Borisov ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, 3428330a5827SNikolay Borisov NULL); 3429765f3cebSNikolay Borisov if (ret) { 3430765f3cebSNikolay Borisov unlock_page(page); 3431765f3cebSNikolay Borisov put_page(page); 3432765f3cebSNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 343343b18595SQu Wenruo PAGE_SIZE, true); 3434765f3cebSNikolay Borisov btrfs_delalloc_release_extents(BTRFS_I(inode), 34358702ba93SQu Wenruo PAGE_SIZE); 3436765f3cebSNikolay Borisov 3437765f3cebSNikolay Borisov clear_extent_bits(&BTRFS_I(inode)->io_tree, 3438765f3cebSNikolay Borisov page_start, page_end, 3439765f3cebSNikolay Borisov EXTENT_LOCKED | EXTENT_BOUNDARY); 3440765f3cebSNikolay Borisov goto out; 3441765f3cebSNikolay Borisov 3442765f3cebSNikolay Borisov } 34430257bb82SYan, Zheng set_page_dirty(page); 34440257bb82SYan, Zheng 34450257bb82SYan, Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 3446d0082371SJeff Mahoney page_start, page_end); 34470257bb82SYan, Zheng unlock_page(page); 344809cbfeafSKirill A. Shutemov put_page(page); 34490257bb82SYan, Zheng 34500257bb82SYan, Zheng index++; 34518702ba93SQu Wenruo btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); 3452efa56464SYan, Zheng balance_dirty_pages_ratelimited(inode->i_mapping); 34532ff7e61eSJeff Mahoney btrfs_throttle(fs_info); 34547f913c7cSQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 34557f913c7cSQu Wenruo ret = -ECANCELED; 34567f913c7cSQu Wenruo goto out; 34577f913c7cSQu Wenruo } 34580257bb82SYan, Zheng } 34590257bb82SYan, Zheng WARN_ON(nr != cluster->nr); 3460efa56464SYan, Zheng out: 34610257bb82SYan, Zheng kfree(ra); 34620257bb82SYan, Zheng return ret; 34630257bb82SYan, Zheng } 34640257bb82SYan, Zheng 34650257bb82SYan, Zheng static noinline_for_stack 34660257bb82SYan, Zheng int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, 34670257bb82SYan, Zheng struct file_extent_cluster *cluster) 34680257bb82SYan, Zheng { 34690257bb82SYan, Zheng int ret; 34700257bb82SYan, Zheng 34710257bb82SYan, Zheng if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) { 34720257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 34730257bb82SYan, Zheng if (ret) 34740257bb82SYan, Zheng return ret; 34750257bb82SYan, Zheng cluster->nr = 0; 34760257bb82SYan, Zheng } 34770257bb82SYan, Zheng 34780257bb82SYan, Zheng if (!cluster->nr) 34790257bb82SYan, Zheng cluster->start = extent_key->objectid; 34800257bb82SYan, Zheng else 34810257bb82SYan, Zheng BUG_ON(cluster->nr >= MAX_EXTENTS); 34820257bb82SYan, Zheng cluster->end = extent_key->objectid + extent_key->offset - 1; 34830257bb82SYan, Zheng cluster->boundary[cluster->nr] = extent_key->objectid; 34840257bb82SYan, Zheng cluster->nr++; 34850257bb82SYan, Zheng 34860257bb82SYan, Zheng if (cluster->nr >= MAX_EXTENTS) { 34870257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 34880257bb82SYan, Zheng if (ret) 34890257bb82SYan, Zheng return ret; 34900257bb82SYan, Zheng cluster->nr = 0; 34910257bb82SYan, Zheng } 34920257bb82SYan, Zheng return 0; 34935d4f98a2SYan Zheng } 34945d4f98a2SYan Zheng 34955d4f98a2SYan Zheng /* 34965d4f98a2SYan Zheng * helper to add a tree block to the list. 34975d4f98a2SYan Zheng * the major work is getting the generation and level of the block 34985d4f98a2SYan Zheng */ 34995d4f98a2SYan Zheng static int add_tree_block(struct reloc_control *rc, 35005d4f98a2SYan Zheng struct btrfs_key *extent_key, 35015d4f98a2SYan Zheng struct btrfs_path *path, 35025d4f98a2SYan Zheng struct rb_root *blocks) 35035d4f98a2SYan Zheng { 35045d4f98a2SYan Zheng struct extent_buffer *eb; 35055d4f98a2SYan Zheng struct btrfs_extent_item *ei; 35065d4f98a2SYan Zheng struct btrfs_tree_block_info *bi; 35075d4f98a2SYan Zheng struct tree_block *block; 35085d4f98a2SYan Zheng struct rb_node *rb_node; 35095d4f98a2SYan Zheng u32 item_size; 35105d4f98a2SYan Zheng int level = -1; 35117fdf4b60SWang Shilong u64 generation; 35125d4f98a2SYan Zheng 35135d4f98a2SYan Zheng eb = path->nodes[0]; 35145d4f98a2SYan Zheng item_size = btrfs_item_size_nr(eb, path->slots[0]); 35155d4f98a2SYan Zheng 35163173a18fSJosef Bacik if (extent_key->type == BTRFS_METADATA_ITEM_KEY || 35173173a18fSJosef Bacik item_size >= sizeof(*ei) + sizeof(*bi)) { 35185d4f98a2SYan Zheng ei = btrfs_item_ptr(eb, path->slots[0], 35195d4f98a2SYan Zheng struct btrfs_extent_item); 35203173a18fSJosef Bacik if (extent_key->type == BTRFS_EXTENT_ITEM_KEY) { 35215d4f98a2SYan Zheng bi = (struct btrfs_tree_block_info *)(ei + 1); 35225d4f98a2SYan Zheng level = btrfs_tree_block_level(eb, bi); 35235d4f98a2SYan Zheng } else { 35243173a18fSJosef Bacik level = (int)extent_key->offset; 35253173a18fSJosef Bacik } 35263173a18fSJosef Bacik generation = btrfs_extent_generation(eb, ei); 35276d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3528ba3c2b19SNikolay Borisov btrfs_print_v0_err(eb->fs_info); 3529ba3c2b19SNikolay Borisov btrfs_handle_fs_error(eb->fs_info, -EINVAL, NULL); 3530ba3c2b19SNikolay Borisov return -EINVAL; 35313173a18fSJosef Bacik } else { 35325d4f98a2SYan Zheng BUG(); 35335d4f98a2SYan Zheng } 35345d4f98a2SYan Zheng 3535b3b4aa74SDavid Sterba btrfs_release_path(path); 35365d4f98a2SYan Zheng 35375d4f98a2SYan Zheng BUG_ON(level == -1); 35385d4f98a2SYan Zheng 35395d4f98a2SYan Zheng block = kmalloc(sizeof(*block), GFP_NOFS); 35405d4f98a2SYan Zheng if (!block) 35415d4f98a2SYan Zheng return -ENOMEM; 35425d4f98a2SYan Zheng 35435d4f98a2SYan Zheng block->bytenr = extent_key->objectid; 3544da17066cSJeff Mahoney block->key.objectid = rc->extent_root->fs_info->nodesize; 35455d4f98a2SYan Zheng block->key.offset = generation; 35465d4f98a2SYan Zheng block->level = level; 35475d4f98a2SYan Zheng block->key_ready = 0; 35485d4f98a2SYan Zheng 35495d4f98a2SYan Zheng rb_node = tree_insert(blocks, block->bytenr, &block->rb_node); 355043c04fb1SJeff Mahoney if (rb_node) 355143c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, block->bytenr); 35525d4f98a2SYan Zheng 35535d4f98a2SYan Zheng return 0; 35545d4f98a2SYan Zheng } 35555d4f98a2SYan Zheng 35565d4f98a2SYan Zheng /* 35575d4f98a2SYan Zheng * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY 35585d4f98a2SYan Zheng */ 35595d4f98a2SYan Zheng static int __add_tree_block(struct reloc_control *rc, 35605d4f98a2SYan Zheng u64 bytenr, u32 blocksize, 35615d4f98a2SYan Zheng struct rb_root *blocks) 35625d4f98a2SYan Zheng { 35630b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 35645d4f98a2SYan Zheng struct btrfs_path *path; 35655d4f98a2SYan Zheng struct btrfs_key key; 35665d4f98a2SYan Zheng int ret; 35670b246afaSJeff Mahoney bool skinny = btrfs_fs_incompat(fs_info, SKINNY_METADATA); 35685d4f98a2SYan Zheng 35697476dfdaSDavid Sterba if (tree_block_processed(bytenr, rc)) 35705d4f98a2SYan Zheng return 0; 35715d4f98a2SYan Zheng 35725d4f98a2SYan Zheng if (tree_search(blocks, bytenr)) 35735d4f98a2SYan Zheng return 0; 35745d4f98a2SYan Zheng 35755d4f98a2SYan Zheng path = btrfs_alloc_path(); 35765d4f98a2SYan Zheng if (!path) 35775d4f98a2SYan Zheng return -ENOMEM; 3578aee68ee5SJosef Bacik again: 35795d4f98a2SYan Zheng key.objectid = bytenr; 3580aee68ee5SJosef Bacik if (skinny) { 3581aee68ee5SJosef Bacik key.type = BTRFS_METADATA_ITEM_KEY; 3582aee68ee5SJosef Bacik key.offset = (u64)-1; 3583aee68ee5SJosef Bacik } else { 35845d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 35855d4f98a2SYan Zheng key.offset = blocksize; 3586aee68ee5SJosef Bacik } 35875d4f98a2SYan Zheng 35885d4f98a2SYan Zheng path->search_commit_root = 1; 35895d4f98a2SYan Zheng path->skip_locking = 1; 35905d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); 35915d4f98a2SYan Zheng if (ret < 0) 35925d4f98a2SYan Zheng goto out; 35935d4f98a2SYan Zheng 3594aee68ee5SJosef Bacik if (ret > 0 && skinny) { 3595aee68ee5SJosef Bacik if (path->slots[0]) { 3596aee68ee5SJosef Bacik path->slots[0]--; 3597aee68ee5SJosef Bacik btrfs_item_key_to_cpu(path->nodes[0], &key, 3598aee68ee5SJosef Bacik path->slots[0]); 35993173a18fSJosef Bacik if (key.objectid == bytenr && 3600aee68ee5SJosef Bacik (key.type == BTRFS_METADATA_ITEM_KEY || 3601aee68ee5SJosef Bacik (key.type == BTRFS_EXTENT_ITEM_KEY && 3602aee68ee5SJosef Bacik key.offset == blocksize))) 36033173a18fSJosef Bacik ret = 0; 36043173a18fSJosef Bacik } 3605aee68ee5SJosef Bacik 3606aee68ee5SJosef Bacik if (ret) { 3607aee68ee5SJosef Bacik skinny = false; 3608aee68ee5SJosef Bacik btrfs_release_path(path); 3609aee68ee5SJosef Bacik goto again; 3610aee68ee5SJosef Bacik } 3611aee68ee5SJosef Bacik } 3612cdccee99SLiu Bo if (ret) { 3613cdccee99SLiu Bo ASSERT(ret == 1); 3614cdccee99SLiu Bo btrfs_print_leaf(path->nodes[0]); 3615cdccee99SLiu Bo btrfs_err(fs_info, 3616cdccee99SLiu Bo "tree block extent item (%llu) is not found in extent tree", 3617cdccee99SLiu Bo bytenr); 3618cdccee99SLiu Bo WARN_ON(1); 3619cdccee99SLiu Bo ret = -EINVAL; 3620cdccee99SLiu Bo goto out; 3621cdccee99SLiu Bo } 36223173a18fSJosef Bacik 36235d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, blocks); 36245d4f98a2SYan Zheng out: 36255d4f98a2SYan Zheng btrfs_free_path(path); 36265d4f98a2SYan Zheng return ret; 36275d4f98a2SYan Zheng } 36285d4f98a2SYan Zheng 36290af3d00bSJosef Bacik static int delete_block_group_cache(struct btrfs_fs_info *fs_info, 363032da5386SDavid Sterba struct btrfs_block_group *block_group, 36311bbc621eSChris Mason struct inode *inode, 36321bbc621eSChris Mason u64 ino) 36330af3d00bSJosef Bacik { 36340af3d00bSJosef Bacik struct btrfs_key key; 36350af3d00bSJosef Bacik struct btrfs_root *root = fs_info->tree_root; 36360af3d00bSJosef Bacik struct btrfs_trans_handle *trans; 36370af3d00bSJosef Bacik int ret = 0; 36380af3d00bSJosef Bacik 36390af3d00bSJosef Bacik if (inode) 36400af3d00bSJosef Bacik goto truncate; 36410af3d00bSJosef Bacik 36420af3d00bSJosef Bacik key.objectid = ino; 36430af3d00bSJosef Bacik key.type = BTRFS_INODE_ITEM_KEY; 36440af3d00bSJosef Bacik key.offset = 0; 36450af3d00bSJosef Bacik 36464c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 36472e19f1f9SAl Viro if (IS_ERR(inode)) 36480af3d00bSJosef Bacik return -ENOENT; 36490af3d00bSJosef Bacik 36500af3d00bSJosef Bacik truncate: 36512ff7e61eSJeff Mahoney ret = btrfs_check_trunc_cache_free_space(fs_info, 36527b61cd92SMiao Xie &fs_info->global_block_rsv); 36537b61cd92SMiao Xie if (ret) 36547b61cd92SMiao Xie goto out; 36557b61cd92SMiao Xie 36567a7eaa40SJosef Bacik trans = btrfs_join_transaction(root); 36570af3d00bSJosef Bacik if (IS_ERR(trans)) { 36583612b495STsutomu Itoh ret = PTR_ERR(trans); 36590af3d00bSJosef Bacik goto out; 36600af3d00bSJosef Bacik } 36610af3d00bSJosef Bacik 366277ab86bfSJeff Mahoney ret = btrfs_truncate_free_space_cache(trans, block_group, inode); 36630af3d00bSJosef Bacik 36643a45bb20SJeff Mahoney btrfs_end_transaction(trans); 36652ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 36660af3d00bSJosef Bacik out: 36670af3d00bSJosef Bacik iput(inode); 36680af3d00bSJosef Bacik return ret; 36690af3d00bSJosef Bacik } 36700af3d00bSJosef Bacik 36715d4f98a2SYan Zheng /* 367219b546d7SQu Wenruo * Locate the free space cache EXTENT_DATA in root tree leaf and delete the 367319b546d7SQu Wenruo * cache inode, to avoid free space cache data extent blocking data relocation. 36745d4f98a2SYan Zheng */ 367519b546d7SQu Wenruo static int delete_v1_space_cache(struct extent_buffer *leaf, 367619b546d7SQu Wenruo struct btrfs_block_group *block_group, 367719b546d7SQu Wenruo u64 data_bytenr) 36785d4f98a2SYan Zheng { 367919b546d7SQu Wenruo u64 space_cache_ino; 368019b546d7SQu Wenruo struct btrfs_file_extent_item *ei; 36815d4f98a2SYan Zheng struct btrfs_key key; 368219b546d7SQu Wenruo bool found = false; 368319b546d7SQu Wenruo int i; 36845d4f98a2SYan Zheng int ret; 36855d4f98a2SYan Zheng 368619b546d7SQu Wenruo if (btrfs_header_owner(leaf) != BTRFS_ROOT_TREE_OBJECTID) 368719b546d7SQu Wenruo return 0; 36885d4f98a2SYan Zheng 368919b546d7SQu Wenruo for (i = 0; i < btrfs_header_nritems(leaf); i++) { 369019b546d7SQu Wenruo btrfs_item_key_to_cpu(leaf, &key, i); 369119b546d7SQu Wenruo if (key.type != BTRFS_EXTENT_DATA_KEY) 369219b546d7SQu Wenruo continue; 369319b546d7SQu Wenruo ei = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 369419b546d7SQu Wenruo if (btrfs_file_extent_type(leaf, ei) == BTRFS_FILE_EXTENT_REG && 369519b546d7SQu Wenruo btrfs_file_extent_disk_bytenr(leaf, ei) == data_bytenr) { 369619b546d7SQu Wenruo found = true; 369719b546d7SQu Wenruo space_cache_ino = key.objectid; 369819b546d7SQu Wenruo break; 369919b546d7SQu Wenruo } 370019b546d7SQu Wenruo } 370119b546d7SQu Wenruo if (!found) 370219b546d7SQu Wenruo return -ENOENT; 370319b546d7SQu Wenruo ret = delete_block_group_cache(leaf->fs_info, block_group, NULL, 370419b546d7SQu Wenruo space_cache_ino); 37050af3d00bSJosef Bacik return ret; 37065d4f98a2SYan Zheng } 37075d4f98a2SYan Zheng 37085d4f98a2SYan Zheng /* 37092c016dc2SLiu Bo * helper to find all tree blocks that reference a given data extent 37105d4f98a2SYan Zheng */ 37115d4f98a2SYan Zheng static noinline_for_stack 37125d4f98a2SYan Zheng int add_data_references(struct reloc_control *rc, 37135d4f98a2SYan Zheng struct btrfs_key *extent_key, 37145d4f98a2SYan Zheng struct btrfs_path *path, 37155d4f98a2SYan Zheng struct rb_root *blocks) 37165d4f98a2SYan Zheng { 371719b546d7SQu Wenruo struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 371819b546d7SQu Wenruo struct ulist *leaves = NULL; 371919b546d7SQu Wenruo struct ulist_iterator leaf_uiter; 372019b546d7SQu Wenruo struct ulist_node *ref_node = NULL; 372119b546d7SQu Wenruo const u32 blocksize = fs_info->nodesize; 3722647f63bdSFilipe David Borba Manana int ret = 0; 37235d4f98a2SYan Zheng 3724b3b4aa74SDavid Sterba btrfs_release_path(path); 372519b546d7SQu Wenruo ret = btrfs_find_all_leafs(NULL, fs_info, extent_key->objectid, 372619b546d7SQu Wenruo 0, &leaves, NULL, true); 372719b546d7SQu Wenruo if (ret < 0) 372819b546d7SQu Wenruo return ret; 372919b546d7SQu Wenruo 373019b546d7SQu Wenruo ULIST_ITER_INIT(&leaf_uiter); 373119b546d7SQu Wenruo while ((ref_node = ulist_next(leaves, &leaf_uiter))) { 373219b546d7SQu Wenruo struct extent_buffer *eb; 373319b546d7SQu Wenruo 373419b546d7SQu Wenruo eb = read_tree_block(fs_info, ref_node->val, 0, 0, NULL); 373519b546d7SQu Wenruo if (IS_ERR(eb)) { 373619b546d7SQu Wenruo ret = PTR_ERR(eb); 373719b546d7SQu Wenruo break; 373819b546d7SQu Wenruo } 373919b546d7SQu Wenruo ret = delete_v1_space_cache(eb, rc->block_group, 374019b546d7SQu Wenruo extent_key->objectid); 374119b546d7SQu Wenruo free_extent_buffer(eb); 374219b546d7SQu Wenruo if (ret < 0) 374319b546d7SQu Wenruo break; 374419b546d7SQu Wenruo ret = __add_tree_block(rc, ref_node->val, blocksize, blocks); 374519b546d7SQu Wenruo if (ret < 0) 374619b546d7SQu Wenruo break; 374719b546d7SQu Wenruo } 374819b546d7SQu Wenruo if (ret < 0) 37495d4f98a2SYan Zheng free_block_list(blocks); 375019b546d7SQu Wenruo ulist_free(leaves); 375119b546d7SQu Wenruo return ret; 37525d4f98a2SYan Zheng } 37535d4f98a2SYan Zheng 37545d4f98a2SYan Zheng /* 37552c016dc2SLiu Bo * helper to find next unprocessed extent 37565d4f98a2SYan Zheng */ 37575d4f98a2SYan Zheng static noinline_for_stack 3758147d256eSZhaolei int find_next_extent(struct reloc_control *rc, struct btrfs_path *path, 37593fd0a558SYan, Zheng struct btrfs_key *extent_key) 37605d4f98a2SYan Zheng { 37610b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37625d4f98a2SYan Zheng struct btrfs_key key; 37635d4f98a2SYan Zheng struct extent_buffer *leaf; 37645d4f98a2SYan Zheng u64 start, end, last; 37655d4f98a2SYan Zheng int ret; 37665d4f98a2SYan Zheng 3767b3470b5dSDavid Sterba last = rc->block_group->start + rc->block_group->length; 37685d4f98a2SYan Zheng while (1) { 37695d4f98a2SYan Zheng cond_resched(); 37705d4f98a2SYan Zheng if (rc->search_start >= last) { 37715d4f98a2SYan Zheng ret = 1; 37725d4f98a2SYan Zheng break; 37735d4f98a2SYan Zheng } 37745d4f98a2SYan Zheng 37755d4f98a2SYan Zheng key.objectid = rc->search_start; 37765d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 37775d4f98a2SYan Zheng key.offset = 0; 37785d4f98a2SYan Zheng 37795d4f98a2SYan Zheng path->search_commit_root = 1; 37805d4f98a2SYan Zheng path->skip_locking = 1; 37815d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 37825d4f98a2SYan Zheng 0, 0); 37835d4f98a2SYan Zheng if (ret < 0) 37845d4f98a2SYan Zheng break; 37855d4f98a2SYan Zheng next: 37865d4f98a2SYan Zheng leaf = path->nodes[0]; 37875d4f98a2SYan Zheng if (path->slots[0] >= btrfs_header_nritems(leaf)) { 37885d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 37895d4f98a2SYan Zheng if (ret != 0) 37905d4f98a2SYan Zheng break; 37915d4f98a2SYan Zheng leaf = path->nodes[0]; 37925d4f98a2SYan Zheng } 37935d4f98a2SYan Zheng 37945d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 37955d4f98a2SYan Zheng if (key.objectid >= last) { 37965d4f98a2SYan Zheng ret = 1; 37975d4f98a2SYan Zheng break; 37985d4f98a2SYan Zheng } 37995d4f98a2SYan Zheng 38003173a18fSJosef Bacik if (key.type != BTRFS_EXTENT_ITEM_KEY && 38013173a18fSJosef Bacik key.type != BTRFS_METADATA_ITEM_KEY) { 38023173a18fSJosef Bacik path->slots[0]++; 38033173a18fSJosef Bacik goto next; 38043173a18fSJosef Bacik } 38053173a18fSJosef Bacik 38063173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY && 38075d4f98a2SYan Zheng key.objectid + key.offset <= rc->search_start) { 38085d4f98a2SYan Zheng path->slots[0]++; 38095d4f98a2SYan Zheng goto next; 38105d4f98a2SYan Zheng } 38115d4f98a2SYan Zheng 38123173a18fSJosef Bacik if (key.type == BTRFS_METADATA_ITEM_KEY && 38130b246afaSJeff Mahoney key.objectid + fs_info->nodesize <= 38143173a18fSJosef Bacik rc->search_start) { 38153173a18fSJosef Bacik path->slots[0]++; 38163173a18fSJosef Bacik goto next; 38173173a18fSJosef Bacik } 38183173a18fSJosef Bacik 38195d4f98a2SYan Zheng ret = find_first_extent_bit(&rc->processed_blocks, 38205d4f98a2SYan Zheng key.objectid, &start, &end, 3821e6138876SJosef Bacik EXTENT_DIRTY, NULL); 38225d4f98a2SYan Zheng 38235d4f98a2SYan Zheng if (ret == 0 && start <= key.objectid) { 3824b3b4aa74SDavid Sterba btrfs_release_path(path); 38255d4f98a2SYan Zheng rc->search_start = end + 1; 38265d4f98a2SYan Zheng } else { 38273173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY) 38285d4f98a2SYan Zheng rc->search_start = key.objectid + key.offset; 38293173a18fSJosef Bacik else 38303173a18fSJosef Bacik rc->search_start = key.objectid + 38310b246afaSJeff Mahoney fs_info->nodesize; 38323fd0a558SYan, Zheng memcpy(extent_key, &key, sizeof(key)); 38335d4f98a2SYan Zheng return 0; 38345d4f98a2SYan Zheng } 38355d4f98a2SYan Zheng } 3836b3b4aa74SDavid Sterba btrfs_release_path(path); 38375d4f98a2SYan Zheng return ret; 38385d4f98a2SYan Zheng } 38395d4f98a2SYan Zheng 38405d4f98a2SYan Zheng static void set_reloc_control(struct reloc_control *rc) 38415d4f98a2SYan Zheng { 38425d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 38437585717fSChris Mason 38447585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 38455d4f98a2SYan Zheng fs_info->reloc_ctl = rc; 38467585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 38475d4f98a2SYan Zheng } 38485d4f98a2SYan Zheng 38495d4f98a2SYan Zheng static void unset_reloc_control(struct reloc_control *rc) 38505d4f98a2SYan Zheng { 38515d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 38527585717fSChris Mason 38537585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 38545d4f98a2SYan Zheng fs_info->reloc_ctl = NULL; 38557585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 38565d4f98a2SYan Zheng } 38575d4f98a2SYan Zheng 38585d4f98a2SYan Zheng static int check_extent_flags(u64 flags) 38595d4f98a2SYan Zheng { 38605d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 38615d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 38625d4f98a2SYan Zheng return 1; 38635d4f98a2SYan Zheng if (!(flags & BTRFS_EXTENT_FLAG_DATA) && 38645d4f98a2SYan Zheng !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 38655d4f98a2SYan Zheng return 1; 38665d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 38675d4f98a2SYan Zheng (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) 38685d4f98a2SYan Zheng return 1; 38695d4f98a2SYan Zheng return 0; 38705d4f98a2SYan Zheng } 38715d4f98a2SYan Zheng 38723fd0a558SYan, Zheng static noinline_for_stack 38733fd0a558SYan, Zheng int prepare_to_relocate(struct reloc_control *rc) 38743fd0a558SYan, Zheng { 38753fd0a558SYan, Zheng struct btrfs_trans_handle *trans; 3876ac2fabacSJosef Bacik int ret; 38773fd0a558SYan, Zheng 38782ff7e61eSJeff Mahoney rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root->fs_info, 387966d8f3ddSMiao Xie BTRFS_BLOCK_RSV_TEMP); 38803fd0a558SYan, Zheng if (!rc->block_rsv) 38813fd0a558SYan, Zheng return -ENOMEM; 38823fd0a558SYan, Zheng 38833fd0a558SYan, Zheng memset(&rc->cluster, 0, sizeof(rc->cluster)); 3884b3470b5dSDavid Sterba rc->search_start = rc->block_group->start; 38853fd0a558SYan, Zheng rc->extents_found = 0; 38863fd0a558SYan, Zheng rc->nodes_relocated = 0; 38873fd0a558SYan, Zheng rc->merging_rsv_size = 0; 38880647bf56SWang Shilong rc->reserved_bytes = 0; 3889da17066cSJeff Mahoney rc->block_rsv->size = rc->extent_root->fs_info->nodesize * 38900647bf56SWang Shilong RELOCATION_RESERVED_NODES; 3891ac2fabacSJosef Bacik ret = btrfs_block_rsv_refill(rc->extent_root, 3892ac2fabacSJosef Bacik rc->block_rsv, rc->block_rsv->size, 3893ac2fabacSJosef Bacik BTRFS_RESERVE_FLUSH_ALL); 3894ac2fabacSJosef Bacik if (ret) 3895ac2fabacSJosef Bacik return ret; 38963fd0a558SYan, Zheng 38973fd0a558SYan, Zheng rc->create_reloc_tree = 1; 38983fd0a558SYan, Zheng set_reloc_control(rc); 38993fd0a558SYan, Zheng 39007a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 390128818947SLiu Bo if (IS_ERR(trans)) { 390228818947SLiu Bo unset_reloc_control(rc); 390328818947SLiu Bo /* 390428818947SLiu Bo * extent tree is not a ref_cow tree and has no reloc_root to 390528818947SLiu Bo * cleanup. And callers are responsible to free the above 390628818947SLiu Bo * block rsv. 390728818947SLiu Bo */ 390828818947SLiu Bo return PTR_ERR(trans); 390928818947SLiu Bo } 39103a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 39113fd0a558SYan, Zheng return 0; 39123fd0a558SYan, Zheng } 391376dda93cSYan, Zheng 39145d4f98a2SYan Zheng static noinline_for_stack int relocate_block_group(struct reloc_control *rc) 39155d4f98a2SYan Zheng { 39162ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 39175d4f98a2SYan Zheng struct rb_root blocks = RB_ROOT; 39185d4f98a2SYan Zheng struct btrfs_key key; 39195d4f98a2SYan Zheng struct btrfs_trans_handle *trans = NULL; 39205d4f98a2SYan Zheng struct btrfs_path *path; 39215d4f98a2SYan Zheng struct btrfs_extent_item *ei; 39225d4f98a2SYan Zheng u64 flags; 39235d4f98a2SYan Zheng u32 item_size; 39245d4f98a2SYan Zheng int ret; 39255d4f98a2SYan Zheng int err = 0; 3926c87f08caSChris Mason int progress = 0; 39275d4f98a2SYan Zheng 39285d4f98a2SYan Zheng path = btrfs_alloc_path(); 39293fd0a558SYan, Zheng if (!path) 39305d4f98a2SYan Zheng return -ENOMEM; 3931e4058b54SDavid Sterba path->reada = READA_FORWARD; 39323fd0a558SYan, Zheng 39333fd0a558SYan, Zheng ret = prepare_to_relocate(rc); 39343fd0a558SYan, Zheng if (ret) { 39353fd0a558SYan, Zheng err = ret; 39363fd0a558SYan, Zheng goto out_free; 39372423fdfbSJiri Slaby } 39385d4f98a2SYan Zheng 39395d4f98a2SYan Zheng while (1) { 39400647bf56SWang Shilong rc->reserved_bytes = 0; 39410647bf56SWang Shilong ret = btrfs_block_rsv_refill(rc->extent_root, 39420647bf56SWang Shilong rc->block_rsv, rc->block_rsv->size, 39430647bf56SWang Shilong BTRFS_RESERVE_FLUSH_ALL); 39440647bf56SWang Shilong if (ret) { 39450647bf56SWang Shilong err = ret; 39460647bf56SWang Shilong break; 39470647bf56SWang Shilong } 3948c87f08caSChris Mason progress++; 3949a22285a6SYan, Zheng trans = btrfs_start_transaction(rc->extent_root, 0); 39500f788c58SLiu Bo if (IS_ERR(trans)) { 39510f788c58SLiu Bo err = PTR_ERR(trans); 39520f788c58SLiu Bo trans = NULL; 39530f788c58SLiu Bo break; 39540f788c58SLiu Bo } 3955c87f08caSChris Mason restart: 39563fd0a558SYan, Zheng if (update_backref_cache(trans, &rc->backref_cache)) { 39573a45bb20SJeff Mahoney btrfs_end_transaction(trans); 395842a657f5SPan Bian trans = NULL; 39593fd0a558SYan, Zheng continue; 39603fd0a558SYan, Zheng } 39613fd0a558SYan, Zheng 3962147d256eSZhaolei ret = find_next_extent(rc, path, &key); 39635d4f98a2SYan Zheng if (ret < 0) 39645d4f98a2SYan Zheng err = ret; 39655d4f98a2SYan Zheng if (ret != 0) 39665d4f98a2SYan Zheng break; 39675d4f98a2SYan Zheng 39685d4f98a2SYan Zheng rc->extents_found++; 39695d4f98a2SYan Zheng 39705d4f98a2SYan Zheng ei = btrfs_item_ptr(path->nodes[0], path->slots[0], 39715d4f98a2SYan Zheng struct btrfs_extent_item); 39723fd0a558SYan, Zheng item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); 39735d4f98a2SYan Zheng if (item_size >= sizeof(*ei)) { 39745d4f98a2SYan Zheng flags = btrfs_extent_flags(path->nodes[0], ei); 39755d4f98a2SYan Zheng ret = check_extent_flags(flags); 39765d4f98a2SYan Zheng BUG_ON(ret); 39776d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3978ba3c2b19SNikolay Borisov err = -EINVAL; 3979ba3c2b19SNikolay Borisov btrfs_print_v0_err(trans->fs_info); 3980ba3c2b19SNikolay Borisov btrfs_abort_transaction(trans, err); 3981ba3c2b19SNikolay Borisov break; 39825d4f98a2SYan Zheng } else { 39835d4f98a2SYan Zheng BUG(); 39845d4f98a2SYan Zheng } 39855d4f98a2SYan Zheng 39865d4f98a2SYan Zheng if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 39875d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, &blocks); 39885d4f98a2SYan Zheng } else if (rc->stage == UPDATE_DATA_PTRS && 39895d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 39905d4f98a2SYan Zheng ret = add_data_references(rc, &key, path, &blocks); 39915d4f98a2SYan Zheng } else { 3992b3b4aa74SDavid Sterba btrfs_release_path(path); 39935d4f98a2SYan Zheng ret = 0; 39945d4f98a2SYan Zheng } 39955d4f98a2SYan Zheng if (ret < 0) { 39963fd0a558SYan, Zheng err = ret; 39975d4f98a2SYan Zheng break; 39985d4f98a2SYan Zheng } 39995d4f98a2SYan Zheng 40005d4f98a2SYan Zheng if (!RB_EMPTY_ROOT(&blocks)) { 40015d4f98a2SYan Zheng ret = relocate_tree_blocks(trans, rc, &blocks); 40025d4f98a2SYan Zheng if (ret < 0) { 40033fd0a558SYan, Zheng if (ret != -EAGAIN) { 40045d4f98a2SYan Zheng err = ret; 40055d4f98a2SYan Zheng break; 40065d4f98a2SYan Zheng } 40073fd0a558SYan, Zheng rc->extents_found--; 40083fd0a558SYan, Zheng rc->search_start = key.objectid; 40093fd0a558SYan, Zheng } 40105d4f98a2SYan Zheng } 40115d4f98a2SYan Zheng 40123a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 40132ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 40143fd0a558SYan, Zheng trans = NULL; 40155d4f98a2SYan Zheng 40165d4f98a2SYan Zheng if (rc->stage == MOVE_DATA_EXTENTS && 40175d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 40185d4f98a2SYan Zheng rc->found_file_extent = 1; 40190257bb82SYan, Zheng ret = relocate_data_extent(rc->data_inode, 40203fd0a558SYan, Zheng &key, &rc->cluster); 40215d4f98a2SYan Zheng if (ret < 0) { 40225d4f98a2SYan Zheng err = ret; 40235d4f98a2SYan Zheng break; 40245d4f98a2SYan Zheng } 40255d4f98a2SYan Zheng } 4026f31ea088SQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 4027f31ea088SQu Wenruo err = -ECANCELED; 4028f31ea088SQu Wenruo break; 4029f31ea088SQu Wenruo } 40305d4f98a2SYan Zheng } 4031c87f08caSChris Mason if (trans && progress && err == -ENOSPC) { 403243a7e99dSNikolay Borisov ret = btrfs_force_chunk_alloc(trans, rc->block_group->flags); 40339689457bSShilong Wang if (ret == 1) { 4034c87f08caSChris Mason err = 0; 4035c87f08caSChris Mason progress = 0; 4036c87f08caSChris Mason goto restart; 4037c87f08caSChris Mason } 4038c87f08caSChris Mason } 40393fd0a558SYan, Zheng 4040b3b4aa74SDavid Sterba btrfs_release_path(path); 404191166212SDavid Sterba clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY); 40425d4f98a2SYan Zheng 40435d4f98a2SYan Zheng if (trans) { 40443a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 40452ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 40465d4f98a2SYan Zheng } 40475d4f98a2SYan Zheng 40480257bb82SYan, Zheng if (!err) { 40493fd0a558SYan, Zheng ret = relocate_file_extent_cluster(rc->data_inode, 40503fd0a558SYan, Zheng &rc->cluster); 40510257bb82SYan, Zheng if (ret < 0) 40520257bb82SYan, Zheng err = ret; 40530257bb82SYan, Zheng } 40540257bb82SYan, Zheng 40553fd0a558SYan, Zheng rc->create_reloc_tree = 0; 40563fd0a558SYan, Zheng set_reloc_control(rc); 40570257bb82SYan, Zheng 40583fd0a558SYan, Zheng backref_cache_cleanup(&rc->backref_cache); 405963f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 40605d4f98a2SYan Zheng 40617f913c7cSQu Wenruo /* 40627f913c7cSQu Wenruo * Even in the case when the relocation is cancelled, we should all go 40637f913c7cSQu Wenruo * through prepare_to_merge() and merge_reloc_roots(). 40647f913c7cSQu Wenruo * 40657f913c7cSQu Wenruo * For error (including cancelled balance), prepare_to_merge() will 40667f913c7cSQu Wenruo * mark all reloc trees orphan, then queue them for cleanup in 40677f913c7cSQu Wenruo * merge_reloc_roots() 40687f913c7cSQu Wenruo */ 40693fd0a558SYan, Zheng err = prepare_to_merge(rc, err); 40705d4f98a2SYan Zheng 40715d4f98a2SYan Zheng merge_reloc_roots(rc); 40725d4f98a2SYan Zheng 40733fd0a558SYan, Zheng rc->merge_reloc_tree = 0; 40745d4f98a2SYan Zheng unset_reloc_control(rc); 407563f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 40765d4f98a2SYan Zheng 40775d4f98a2SYan Zheng /* get rid of pinned extents */ 40787a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 407962b99540SQu Wenruo if (IS_ERR(trans)) { 40803612b495STsutomu Itoh err = PTR_ERR(trans); 408162b99540SQu Wenruo goto out_free; 408262b99540SQu Wenruo } 40833a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 40846217b0faSJosef Bacik out_free: 4085d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 4086d2311e69SQu Wenruo if (ret < 0 && !err) 4087d2311e69SQu Wenruo err = ret; 40882ff7e61eSJeff Mahoney btrfs_free_block_rsv(fs_info, rc->block_rsv); 40893fd0a558SYan, Zheng btrfs_free_path(path); 40905d4f98a2SYan Zheng return err; 40915d4f98a2SYan Zheng } 40925d4f98a2SYan Zheng 40935d4f98a2SYan Zheng static int __insert_orphan_inode(struct btrfs_trans_handle *trans, 40940257bb82SYan, Zheng struct btrfs_root *root, u64 objectid) 40955d4f98a2SYan Zheng { 40965d4f98a2SYan Zheng struct btrfs_path *path; 40975d4f98a2SYan Zheng struct btrfs_inode_item *item; 40985d4f98a2SYan Zheng struct extent_buffer *leaf; 40995d4f98a2SYan Zheng int ret; 41005d4f98a2SYan Zheng 41015d4f98a2SYan Zheng path = btrfs_alloc_path(); 41025d4f98a2SYan Zheng if (!path) 41035d4f98a2SYan Zheng return -ENOMEM; 41045d4f98a2SYan Zheng 41055d4f98a2SYan Zheng ret = btrfs_insert_empty_inode(trans, root, path, objectid); 41065d4f98a2SYan Zheng if (ret) 41075d4f98a2SYan Zheng goto out; 41085d4f98a2SYan Zheng 41095d4f98a2SYan Zheng leaf = path->nodes[0]; 41105d4f98a2SYan Zheng item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); 4111b159fa28SDavid Sterba memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item)); 41125d4f98a2SYan Zheng btrfs_set_inode_generation(leaf, item, 1); 41130257bb82SYan, Zheng btrfs_set_inode_size(leaf, item, 0); 41145d4f98a2SYan Zheng btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); 41153fd0a558SYan, Zheng btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS | 41163fd0a558SYan, Zheng BTRFS_INODE_PREALLOC); 41175d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 41185d4f98a2SYan Zheng out: 41195d4f98a2SYan Zheng btrfs_free_path(path); 41205d4f98a2SYan Zheng return ret; 41215d4f98a2SYan Zheng } 41225d4f98a2SYan Zheng 41235d4f98a2SYan Zheng /* 41245d4f98a2SYan Zheng * helper to create inode for data relocation. 41255d4f98a2SYan Zheng * the inode is in data relocation tree and its link count is 0 41265d4f98a2SYan Zheng */ 41273fd0a558SYan, Zheng static noinline_for_stack 41283fd0a558SYan, Zheng struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, 412932da5386SDavid Sterba struct btrfs_block_group *group) 41305d4f98a2SYan Zheng { 41315d4f98a2SYan Zheng struct inode *inode = NULL; 41325d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 41335d4f98a2SYan Zheng struct btrfs_root *root; 41345d4f98a2SYan Zheng struct btrfs_key key; 41354624900dSZhaolei u64 objectid; 41365d4f98a2SYan Zheng int err = 0; 41375d4f98a2SYan Zheng 41385d4f98a2SYan Zheng root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 41395d4f98a2SYan Zheng if (IS_ERR(root)) 41405d4f98a2SYan Zheng return ERR_CAST(root); 41415d4f98a2SYan Zheng 4142a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 6); 414376deacf0SJosef Bacik if (IS_ERR(trans)) { 414400246528SJosef Bacik btrfs_put_root(root); 41453fd0a558SYan, Zheng return ERR_CAST(trans); 414676deacf0SJosef Bacik } 41475d4f98a2SYan Zheng 4148581bb050SLi Zefan err = btrfs_find_free_objectid(root, &objectid); 41495d4f98a2SYan Zheng if (err) 41505d4f98a2SYan Zheng goto out; 41515d4f98a2SYan Zheng 41520257bb82SYan, Zheng err = __insert_orphan_inode(trans, root, objectid); 41535d4f98a2SYan Zheng BUG_ON(err); 41545d4f98a2SYan Zheng 41555d4f98a2SYan Zheng key.objectid = objectid; 41565d4f98a2SYan Zheng key.type = BTRFS_INODE_ITEM_KEY; 41575d4f98a2SYan Zheng key.offset = 0; 41584c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 41592e19f1f9SAl Viro BUG_ON(IS_ERR(inode)); 4160b3470b5dSDavid Sterba BTRFS_I(inode)->index_cnt = group->start; 41615d4f98a2SYan Zheng 416273f2e545SNikolay Borisov err = btrfs_orphan_add(trans, BTRFS_I(inode)); 41635d4f98a2SYan Zheng out: 416400246528SJosef Bacik btrfs_put_root(root); 41653a45bb20SJeff Mahoney btrfs_end_transaction(trans); 41662ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 41675d4f98a2SYan Zheng if (err) { 41685d4f98a2SYan Zheng if (inode) 41695d4f98a2SYan Zheng iput(inode); 41705d4f98a2SYan Zheng inode = ERR_PTR(err); 41715d4f98a2SYan Zheng } 41725d4f98a2SYan Zheng return inode; 41735d4f98a2SYan Zheng } 41745d4f98a2SYan Zheng 4175c258d6e3SQu Wenruo static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info) 41763fd0a558SYan, Zheng { 41773fd0a558SYan, Zheng struct reloc_control *rc; 41783fd0a558SYan, Zheng 41793fd0a558SYan, Zheng rc = kzalloc(sizeof(*rc), GFP_NOFS); 41803fd0a558SYan, Zheng if (!rc) 41813fd0a558SYan, Zheng return NULL; 41823fd0a558SYan, Zheng 41833fd0a558SYan, Zheng INIT_LIST_HEAD(&rc->reloc_roots); 4184d2311e69SQu Wenruo INIT_LIST_HEAD(&rc->dirty_subvol_roots); 41853fd0a558SYan, Zheng backref_cache_init(&rc->backref_cache); 41863fd0a558SYan, Zheng mapping_tree_init(&rc->reloc_root_tree); 418743eb5f29SQu Wenruo extent_io_tree_init(fs_info, &rc->processed_blocks, 418843eb5f29SQu Wenruo IO_TREE_RELOC_BLOCKS, NULL); 41893fd0a558SYan, Zheng return rc; 41903fd0a558SYan, Zheng } 41913fd0a558SYan, Zheng 41921a0afa0eSJosef Bacik static void free_reloc_control(struct reloc_control *rc) 41931a0afa0eSJosef Bacik { 41941a0afa0eSJosef Bacik struct mapping_node *node, *tmp; 41951a0afa0eSJosef Bacik 41961a0afa0eSJosef Bacik free_reloc_roots(&rc->reloc_roots); 41971a0afa0eSJosef Bacik rbtree_postorder_for_each_entry_safe(node, tmp, 41981a0afa0eSJosef Bacik &rc->reloc_root_tree.rb_root, rb_node) 41991a0afa0eSJosef Bacik kfree(node); 42001a0afa0eSJosef Bacik 42011a0afa0eSJosef Bacik kfree(rc); 42021a0afa0eSJosef Bacik } 42031a0afa0eSJosef Bacik 42045d4f98a2SYan Zheng /* 4205ebce0e01SAdam Borowski * Print the block group being relocated 4206ebce0e01SAdam Borowski */ 4207ebce0e01SAdam Borowski static void describe_relocation(struct btrfs_fs_info *fs_info, 420832da5386SDavid Sterba struct btrfs_block_group *block_group) 4209ebce0e01SAdam Borowski { 4210f89e09cfSAnand Jain char buf[128] = {'\0'}; 4211ebce0e01SAdam Borowski 4212f89e09cfSAnand Jain btrfs_describe_block_groups(block_group->flags, buf, sizeof(buf)); 4213ebce0e01SAdam Borowski 4214ebce0e01SAdam Borowski btrfs_info(fs_info, 4215ebce0e01SAdam Borowski "relocating block group %llu flags %s", 4216b3470b5dSDavid Sterba block_group->start, buf); 4217ebce0e01SAdam Borowski } 4218ebce0e01SAdam Borowski 4219430640e3SQu Wenruo static const char *stage_to_string(int stage) 4220430640e3SQu Wenruo { 4221430640e3SQu Wenruo if (stage == MOVE_DATA_EXTENTS) 4222430640e3SQu Wenruo return "move data extents"; 4223430640e3SQu Wenruo if (stage == UPDATE_DATA_PTRS) 4224430640e3SQu Wenruo return "update data pointers"; 4225430640e3SQu Wenruo return "unknown"; 4226430640e3SQu Wenruo } 4227430640e3SQu Wenruo 4228ebce0e01SAdam Borowski /* 42295d4f98a2SYan Zheng * function to relocate all extents in a block group. 42305d4f98a2SYan Zheng */ 42316bccf3abSJeff Mahoney int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start) 42325d4f98a2SYan Zheng { 423332da5386SDavid Sterba struct btrfs_block_group *bg; 42346bccf3abSJeff Mahoney struct btrfs_root *extent_root = fs_info->extent_root; 42355d4f98a2SYan Zheng struct reloc_control *rc; 42360af3d00bSJosef Bacik struct inode *inode; 42370af3d00bSJosef Bacik struct btrfs_path *path; 42385d4f98a2SYan Zheng int ret; 4239f0486c68SYan, Zheng int rw = 0; 42405d4f98a2SYan Zheng int err = 0; 42415d4f98a2SYan Zheng 4242eede2bf3SOmar Sandoval bg = btrfs_lookup_block_group(fs_info, group_start); 4243eede2bf3SOmar Sandoval if (!bg) 4244eede2bf3SOmar Sandoval return -ENOENT; 4245eede2bf3SOmar Sandoval 4246eede2bf3SOmar Sandoval if (btrfs_pinned_by_swapfile(fs_info, bg)) { 4247eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 4248eede2bf3SOmar Sandoval return -ETXTBSY; 4249eede2bf3SOmar Sandoval } 4250eede2bf3SOmar Sandoval 4251c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 4252eede2bf3SOmar Sandoval if (!rc) { 4253eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 42545d4f98a2SYan Zheng return -ENOMEM; 4255eede2bf3SOmar Sandoval } 42565d4f98a2SYan Zheng 4257f0486c68SYan, Zheng rc->extent_root = extent_root; 4258eede2bf3SOmar Sandoval rc->block_group = bg; 42595d4f98a2SYan Zheng 4260b12de528SQu Wenruo ret = btrfs_inc_block_group_ro(rc->block_group, true); 4261f0486c68SYan, Zheng if (ret) { 4262f0486c68SYan, Zheng err = ret; 4263f0486c68SYan, Zheng goto out; 4264f0486c68SYan, Zheng } 4265f0486c68SYan, Zheng rw = 1; 4266f0486c68SYan, Zheng 42670af3d00bSJosef Bacik path = btrfs_alloc_path(); 42680af3d00bSJosef Bacik if (!path) { 42690af3d00bSJosef Bacik err = -ENOMEM; 42700af3d00bSJosef Bacik goto out; 42710af3d00bSJosef Bacik } 42720af3d00bSJosef Bacik 42737949f339SDavid Sterba inode = lookup_free_space_inode(rc->block_group, path); 42740af3d00bSJosef Bacik btrfs_free_path(path); 42750af3d00bSJosef Bacik 42760af3d00bSJosef Bacik if (!IS_ERR(inode)) 42771bbc621eSChris Mason ret = delete_block_group_cache(fs_info, rc->block_group, inode, 0); 42780af3d00bSJosef Bacik else 42790af3d00bSJosef Bacik ret = PTR_ERR(inode); 42800af3d00bSJosef Bacik 42810af3d00bSJosef Bacik if (ret && ret != -ENOENT) { 42820af3d00bSJosef Bacik err = ret; 42830af3d00bSJosef Bacik goto out; 42840af3d00bSJosef Bacik } 42850af3d00bSJosef Bacik 42865d4f98a2SYan Zheng rc->data_inode = create_reloc_inode(fs_info, rc->block_group); 42875d4f98a2SYan Zheng if (IS_ERR(rc->data_inode)) { 42885d4f98a2SYan Zheng err = PTR_ERR(rc->data_inode); 42895d4f98a2SYan Zheng rc->data_inode = NULL; 42905d4f98a2SYan Zheng goto out; 42915d4f98a2SYan Zheng } 42925d4f98a2SYan Zheng 42930b246afaSJeff Mahoney describe_relocation(fs_info, rc->block_group); 42945d4f98a2SYan Zheng 42959cfa3e34SFilipe Manana btrfs_wait_block_group_reservations(rc->block_group); 4296f78c436cSFilipe Manana btrfs_wait_nocow_writers(rc->block_group); 42976374e57aSChris Mason btrfs_wait_ordered_roots(fs_info, U64_MAX, 4298b3470b5dSDavid Sterba rc->block_group->start, 4299b3470b5dSDavid Sterba rc->block_group->length); 43005d4f98a2SYan Zheng 43015d4f98a2SYan Zheng while (1) { 4302430640e3SQu Wenruo int finishes_stage; 4303430640e3SQu Wenruo 430476dda93cSYan, Zheng mutex_lock(&fs_info->cleaner_mutex); 43055d4f98a2SYan Zheng ret = relocate_block_group(rc); 430676dda93cSYan, Zheng mutex_unlock(&fs_info->cleaner_mutex); 4307ff612ba7SJosef Bacik if (ret < 0) 43085d4f98a2SYan Zheng err = ret; 4309ff612ba7SJosef Bacik 4310430640e3SQu Wenruo finishes_stage = rc->stage; 4311ff612ba7SJosef Bacik /* 4312ff612ba7SJosef Bacik * We may have gotten ENOSPC after we already dirtied some 4313ff612ba7SJosef Bacik * extents. If writeout happens while we're relocating a 4314ff612ba7SJosef Bacik * different block group we could end up hitting the 4315ff612ba7SJosef Bacik * BUG_ON(rc->stage == UPDATE_DATA_PTRS) in 4316ff612ba7SJosef Bacik * btrfs_reloc_cow_block. Make sure we write everything out 4317ff612ba7SJosef Bacik * properly so we don't trip over this problem, and then break 4318ff612ba7SJosef Bacik * out of the loop if we hit an error. 4319ff612ba7SJosef Bacik */ 4320ff612ba7SJosef Bacik if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { 4321ff612ba7SJosef Bacik ret = btrfs_wait_ordered_range(rc->data_inode, 0, 4322ff612ba7SJosef Bacik (u64)-1); 4323ff612ba7SJosef Bacik if (ret) 4324ff612ba7SJosef Bacik err = ret; 4325ff612ba7SJosef Bacik invalidate_mapping_pages(rc->data_inode->i_mapping, 4326ff612ba7SJosef Bacik 0, -1); 4327ff612ba7SJosef Bacik rc->stage = UPDATE_DATA_PTRS; 43285d4f98a2SYan Zheng } 43295d4f98a2SYan Zheng 4330ff612ba7SJosef Bacik if (err < 0) 4331ff612ba7SJosef Bacik goto out; 4332ff612ba7SJosef Bacik 43335d4f98a2SYan Zheng if (rc->extents_found == 0) 43345d4f98a2SYan Zheng break; 43355d4f98a2SYan Zheng 4336430640e3SQu Wenruo btrfs_info(fs_info, "found %llu extents, stage: %s", 4337430640e3SQu Wenruo rc->extents_found, stage_to_string(finishes_stage)); 43385d4f98a2SYan Zheng } 43395d4f98a2SYan Zheng 43405d4f98a2SYan Zheng WARN_ON(rc->block_group->pinned > 0); 43415d4f98a2SYan Zheng WARN_ON(rc->block_group->reserved > 0); 4342bf38be65SDavid Sterba WARN_ON(rc->block_group->used > 0); 43435d4f98a2SYan Zheng out: 4344f0486c68SYan, Zheng if (err && rw) 43452ff7e61eSJeff Mahoney btrfs_dec_block_group_ro(rc->block_group); 43465d4f98a2SYan Zheng iput(rc->data_inode); 43475d4f98a2SYan Zheng btrfs_put_block_group(rc->block_group); 43481a0afa0eSJosef Bacik free_reloc_control(rc); 43495d4f98a2SYan Zheng return err; 43505d4f98a2SYan Zheng } 43515d4f98a2SYan Zheng 435276dda93cSYan, Zheng static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) 435376dda93cSYan, Zheng { 43540b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 435576dda93cSYan, Zheng struct btrfs_trans_handle *trans; 435679787eaaSJeff Mahoney int ret, err; 435776dda93cSYan, Zheng 43580b246afaSJeff Mahoney trans = btrfs_start_transaction(fs_info->tree_root, 0); 435979787eaaSJeff Mahoney if (IS_ERR(trans)) 436079787eaaSJeff Mahoney return PTR_ERR(trans); 436176dda93cSYan, Zheng 436276dda93cSYan, Zheng memset(&root->root_item.drop_progress, 0, 436376dda93cSYan, Zheng sizeof(root->root_item.drop_progress)); 436476dda93cSYan, Zheng root->root_item.drop_level = 0; 436576dda93cSYan, Zheng btrfs_set_root_refs(&root->root_item, 0); 43660b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 436776dda93cSYan, Zheng &root->root_key, &root->root_item); 436876dda93cSYan, Zheng 43693a45bb20SJeff Mahoney err = btrfs_end_transaction(trans); 437079787eaaSJeff Mahoney if (err) 437179787eaaSJeff Mahoney return err; 437279787eaaSJeff Mahoney return ret; 437376dda93cSYan, Zheng } 437476dda93cSYan, Zheng 43755d4f98a2SYan Zheng /* 43765d4f98a2SYan Zheng * recover relocation interrupted by system crash. 43775d4f98a2SYan Zheng * 43785d4f98a2SYan Zheng * this function resumes merging reloc trees with corresponding fs trees. 43795d4f98a2SYan Zheng * this is important for keeping the sharing of tree blocks 43805d4f98a2SYan Zheng */ 43815d4f98a2SYan Zheng int btrfs_recover_relocation(struct btrfs_root *root) 43825d4f98a2SYan Zheng { 43830b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 43845d4f98a2SYan Zheng LIST_HEAD(reloc_roots); 43855d4f98a2SYan Zheng struct btrfs_key key; 43865d4f98a2SYan Zheng struct btrfs_root *fs_root; 43875d4f98a2SYan Zheng struct btrfs_root *reloc_root; 43885d4f98a2SYan Zheng struct btrfs_path *path; 43895d4f98a2SYan Zheng struct extent_buffer *leaf; 43905d4f98a2SYan Zheng struct reloc_control *rc = NULL; 43915d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 43925d4f98a2SYan Zheng int ret; 43935d4f98a2SYan Zheng int err = 0; 43945d4f98a2SYan Zheng 43955d4f98a2SYan Zheng path = btrfs_alloc_path(); 43965d4f98a2SYan Zheng if (!path) 43975d4f98a2SYan Zheng return -ENOMEM; 4398e4058b54SDavid Sterba path->reada = READA_BACK; 43995d4f98a2SYan Zheng 44005d4f98a2SYan Zheng key.objectid = BTRFS_TREE_RELOC_OBJECTID; 44015d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 44025d4f98a2SYan Zheng key.offset = (u64)-1; 44035d4f98a2SYan Zheng 44045d4f98a2SYan Zheng while (1) { 44050b246afaSJeff Mahoney ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, 44065d4f98a2SYan Zheng path, 0, 0); 44075d4f98a2SYan Zheng if (ret < 0) { 44085d4f98a2SYan Zheng err = ret; 44095d4f98a2SYan Zheng goto out; 44105d4f98a2SYan Zheng } 44115d4f98a2SYan Zheng if (ret > 0) { 44125d4f98a2SYan Zheng if (path->slots[0] == 0) 44135d4f98a2SYan Zheng break; 44145d4f98a2SYan Zheng path->slots[0]--; 44155d4f98a2SYan Zheng } 44165d4f98a2SYan Zheng leaf = path->nodes[0]; 44175d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4418b3b4aa74SDavid Sterba btrfs_release_path(path); 44195d4f98a2SYan Zheng 44205d4f98a2SYan Zheng if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || 44215d4f98a2SYan Zheng key.type != BTRFS_ROOT_ITEM_KEY) 44225d4f98a2SYan Zheng break; 44235d4f98a2SYan Zheng 44243dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(root, &key); 44255d4f98a2SYan Zheng if (IS_ERR(reloc_root)) { 44265d4f98a2SYan Zheng err = PTR_ERR(reloc_root); 44275d4f98a2SYan Zheng goto out; 44285d4f98a2SYan Zheng } 44295d4f98a2SYan Zheng 44303dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 44315d4f98a2SYan Zheng list_add(&reloc_root->root_list, &reloc_roots); 44325d4f98a2SYan Zheng 44335d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 44340b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, 44355d4f98a2SYan Zheng reloc_root->root_key.offset); 44365d4f98a2SYan Zheng if (IS_ERR(fs_root)) { 443776dda93cSYan, Zheng ret = PTR_ERR(fs_root); 443876dda93cSYan, Zheng if (ret != -ENOENT) { 443976dda93cSYan, Zheng err = ret; 44405d4f98a2SYan Zheng goto out; 44415d4f98a2SYan Zheng } 444279787eaaSJeff Mahoney ret = mark_garbage_root(reloc_root); 444379787eaaSJeff Mahoney if (ret < 0) { 444479787eaaSJeff Mahoney err = ret; 444579787eaaSJeff Mahoney goto out; 444679787eaaSJeff Mahoney } 4447932fd26dSJosef Bacik } else { 444800246528SJosef Bacik btrfs_put_root(fs_root); 444976dda93cSYan, Zheng } 44505d4f98a2SYan Zheng } 44515d4f98a2SYan Zheng 44525d4f98a2SYan Zheng if (key.offset == 0) 44535d4f98a2SYan Zheng break; 44545d4f98a2SYan Zheng 44555d4f98a2SYan Zheng key.offset--; 44565d4f98a2SYan Zheng } 4457b3b4aa74SDavid Sterba btrfs_release_path(path); 44585d4f98a2SYan Zheng 44595d4f98a2SYan Zheng if (list_empty(&reloc_roots)) 44605d4f98a2SYan Zheng goto out; 44615d4f98a2SYan Zheng 4462c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 44635d4f98a2SYan Zheng if (!rc) { 44645d4f98a2SYan Zheng err = -ENOMEM; 44655d4f98a2SYan Zheng goto out; 44665d4f98a2SYan Zheng } 44675d4f98a2SYan Zheng 44680b246afaSJeff Mahoney rc->extent_root = fs_info->extent_root; 44695d4f98a2SYan Zheng 44705d4f98a2SYan Zheng set_reloc_control(rc); 44715d4f98a2SYan Zheng 44727a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 44733612b495STsutomu Itoh if (IS_ERR(trans)) { 44743612b495STsutomu Itoh err = PTR_ERR(trans); 4475fb2d83eeSJosef Bacik goto out_unset; 44763612b495STsutomu Itoh } 44773fd0a558SYan, Zheng 44783fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 44793fd0a558SYan, Zheng 44805d4f98a2SYan Zheng while (!list_empty(&reloc_roots)) { 44815d4f98a2SYan Zheng reloc_root = list_entry(reloc_roots.next, 44825d4f98a2SYan Zheng struct btrfs_root, root_list); 44835d4f98a2SYan Zheng list_del(&reloc_root->root_list); 44845d4f98a2SYan Zheng 44855d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) == 0) { 44865d4f98a2SYan Zheng list_add_tail(&reloc_root->root_list, 44875d4f98a2SYan Zheng &rc->reloc_roots); 44885d4f98a2SYan Zheng continue; 44895d4f98a2SYan Zheng } 44905d4f98a2SYan Zheng 44910b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, reloc_root->root_key.offset); 449279787eaaSJeff Mahoney if (IS_ERR(fs_root)) { 449379787eaaSJeff Mahoney err = PTR_ERR(fs_root); 4494ca1aa281SJosef Bacik list_add_tail(&reloc_root->root_list, &reloc_roots); 44951402d17dSXiyu Yang btrfs_end_transaction(trans); 4496fb2d83eeSJosef Bacik goto out_unset; 449779787eaaSJeff Mahoney } 44985d4f98a2SYan Zheng 4499ffd7b339SJeff Mahoney err = __add_reloc_root(reloc_root); 450079787eaaSJeff Mahoney BUG_ON(err < 0); /* -ENOMEM or logic error */ 4501f44deb74SJosef Bacik fs_root->reloc_root = btrfs_grab_root(reloc_root); 450200246528SJosef Bacik btrfs_put_root(fs_root); 45035d4f98a2SYan Zheng } 45045d4f98a2SYan Zheng 45053a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 450679787eaaSJeff Mahoney if (err) 4507fb2d83eeSJosef Bacik goto out_unset; 45085d4f98a2SYan Zheng 45095d4f98a2SYan Zheng merge_reloc_roots(rc); 45105d4f98a2SYan Zheng 45115d4f98a2SYan Zheng unset_reloc_control(rc); 45125d4f98a2SYan Zheng 45137a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 451462b99540SQu Wenruo if (IS_ERR(trans)) { 45153612b495STsutomu Itoh err = PTR_ERR(trans); 45166217b0faSJosef Bacik goto out_clean; 451762b99540SQu Wenruo } 45183a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 45196217b0faSJosef Bacik out_clean: 4520d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 4521d2311e69SQu Wenruo if (ret < 0 && !err) 4522d2311e69SQu Wenruo err = ret; 4523fb2d83eeSJosef Bacik out_unset: 4524fb2d83eeSJosef Bacik unset_reloc_control(rc); 45251a0afa0eSJosef Bacik free_reloc_control(rc); 45263612b495STsutomu Itoh out: 4527aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 4528aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 4529aca1bba6SLiu Bo 45305d4f98a2SYan Zheng btrfs_free_path(path); 45315d4f98a2SYan Zheng 45325d4f98a2SYan Zheng if (err == 0) { 45335d4f98a2SYan Zheng /* cleanup orphan inode in data relocation tree */ 45340b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 4535932fd26dSJosef Bacik if (IS_ERR(fs_root)) { 45365d4f98a2SYan Zheng err = PTR_ERR(fs_root); 4537932fd26dSJosef Bacik } else { 453866b4ffd1SJosef Bacik err = btrfs_orphan_cleanup(fs_root); 453900246528SJosef Bacik btrfs_put_root(fs_root); 4540932fd26dSJosef Bacik } 4541932fd26dSJosef Bacik } 45425d4f98a2SYan Zheng return err; 45435d4f98a2SYan Zheng } 45445d4f98a2SYan Zheng 45455d4f98a2SYan Zheng /* 45465d4f98a2SYan Zheng * helper to add ordered checksum for data relocation. 45475d4f98a2SYan Zheng * 45485d4f98a2SYan Zheng * cloning checksum properly handles the nodatasum extents. 45495d4f98a2SYan Zheng * it also saves CPU time to re-calculate the checksum. 45505d4f98a2SYan Zheng */ 45515d4f98a2SYan Zheng int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) 45525d4f98a2SYan Zheng { 45530b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 45545d4f98a2SYan Zheng struct btrfs_ordered_sum *sums; 45555d4f98a2SYan Zheng struct btrfs_ordered_extent *ordered; 45565d4f98a2SYan Zheng int ret; 45575d4f98a2SYan Zheng u64 disk_bytenr; 45584577b014SJosef Bacik u64 new_bytenr; 45595d4f98a2SYan Zheng LIST_HEAD(list); 45605d4f98a2SYan Zheng 45615d4f98a2SYan Zheng ordered = btrfs_lookup_ordered_extent(inode, file_pos); 4562bffe633eSOmar Sandoval BUG_ON(ordered->file_offset != file_pos || ordered->num_bytes != len); 45635d4f98a2SYan Zheng 45645d4f98a2SYan Zheng disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; 45650b246afaSJeff Mahoney ret = btrfs_lookup_csums_range(fs_info->csum_root, disk_bytenr, 4566a2de733cSArne Jansen disk_bytenr + len - 1, &list, 0); 456779787eaaSJeff Mahoney if (ret) 456879787eaaSJeff Mahoney goto out; 45695d4f98a2SYan Zheng 45705d4f98a2SYan Zheng while (!list_empty(&list)) { 45715d4f98a2SYan Zheng sums = list_entry(list.next, struct btrfs_ordered_sum, list); 45725d4f98a2SYan Zheng list_del_init(&sums->list); 45735d4f98a2SYan Zheng 45744577b014SJosef Bacik /* 45754577b014SJosef Bacik * We need to offset the new_bytenr based on where the csum is. 45764577b014SJosef Bacik * We need to do this because we will read in entire prealloc 45774577b014SJosef Bacik * extents but we may have written to say the middle of the 45784577b014SJosef Bacik * prealloc extent, so we need to make sure the csum goes with 45794577b014SJosef Bacik * the right disk offset. 45804577b014SJosef Bacik * 45814577b014SJosef Bacik * We can do this because the data reloc inode refers strictly 45824577b014SJosef Bacik * to the on disk bytes, so we don't have to worry about 45834577b014SJosef Bacik * disk_len vs real len like with real inodes since it's all 45844577b014SJosef Bacik * disk length. 45854577b014SJosef Bacik */ 4586bffe633eSOmar Sandoval new_bytenr = ordered->disk_bytenr + sums->bytenr - disk_bytenr; 45874577b014SJosef Bacik sums->bytenr = new_bytenr; 45885d4f98a2SYan Zheng 4589f9756261SNikolay Borisov btrfs_add_ordered_sum(ordered, sums); 45905d4f98a2SYan Zheng } 459179787eaaSJeff Mahoney out: 45925d4f98a2SYan Zheng btrfs_put_ordered_extent(ordered); 4593411fc6bcSAndi Kleen return ret; 45945d4f98a2SYan Zheng } 45953fd0a558SYan, Zheng 459683d4cfd4SJosef Bacik int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, 45973fd0a558SYan, Zheng struct btrfs_root *root, struct extent_buffer *buf, 45983fd0a558SYan, Zheng struct extent_buffer *cow) 45993fd0a558SYan, Zheng { 46000b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 46013fd0a558SYan, Zheng struct reloc_control *rc; 46023fd0a558SYan, Zheng struct backref_node *node; 46033fd0a558SYan, Zheng int first_cow = 0; 46043fd0a558SYan, Zheng int level; 460583d4cfd4SJosef Bacik int ret = 0; 46063fd0a558SYan, Zheng 46070b246afaSJeff Mahoney rc = fs_info->reloc_ctl; 46083fd0a558SYan, Zheng if (!rc) 460983d4cfd4SJosef Bacik return 0; 46103fd0a558SYan, Zheng 46113fd0a558SYan, Zheng BUG_ON(rc->stage == UPDATE_DATA_PTRS && 46123fd0a558SYan, Zheng root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID); 46133fd0a558SYan, Zheng 46143fd0a558SYan, Zheng level = btrfs_header_level(buf); 46153fd0a558SYan, Zheng if (btrfs_header_generation(buf) <= 46163fd0a558SYan, Zheng btrfs_root_last_snapshot(&root->root_item)) 46173fd0a558SYan, Zheng first_cow = 1; 46183fd0a558SYan, Zheng 46193fd0a558SYan, Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID && 46203fd0a558SYan, Zheng rc->create_reloc_tree) { 46213fd0a558SYan, Zheng WARN_ON(!first_cow && level == 0); 46223fd0a558SYan, Zheng 46233fd0a558SYan, Zheng node = rc->backref_cache.path[level]; 46243fd0a558SYan, Zheng BUG_ON(node->bytenr != buf->start && 46253fd0a558SYan, Zheng node->new_bytenr != buf->start); 46263fd0a558SYan, Zheng 46273fd0a558SYan, Zheng drop_node_buffer(node); 462867439dadSDavid Sterba atomic_inc(&cow->refs); 46293fd0a558SYan, Zheng node->eb = cow; 46303fd0a558SYan, Zheng node->new_bytenr = cow->start; 46313fd0a558SYan, Zheng 46323fd0a558SYan, Zheng if (!node->pending) { 46333fd0a558SYan, Zheng list_move_tail(&node->list, 46343fd0a558SYan, Zheng &rc->backref_cache.pending[level]); 46353fd0a558SYan, Zheng node->pending = 1; 46363fd0a558SYan, Zheng } 46373fd0a558SYan, Zheng 46383fd0a558SYan, Zheng if (first_cow) 46393fd0a558SYan, Zheng __mark_block_processed(rc, node); 46403fd0a558SYan, Zheng 46413fd0a558SYan, Zheng if (first_cow && level > 0) 46423fd0a558SYan, Zheng rc->nodes_relocated += buf->len; 46433fd0a558SYan, Zheng } 46443fd0a558SYan, Zheng 464583d4cfd4SJosef Bacik if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) 46463fd0a558SYan, Zheng ret = replace_file_extents(trans, rc, root, cow); 464783d4cfd4SJosef Bacik return ret; 46483fd0a558SYan, Zheng } 46493fd0a558SYan, Zheng 46503fd0a558SYan, Zheng /* 46513fd0a558SYan, Zheng * called before creating snapshot. it calculates metadata reservation 465201327610SNicholas D Steeves * required for relocating tree blocks in the snapshot 46533fd0a558SYan, Zheng */ 4654147d256eSZhaolei void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending, 46553fd0a558SYan, Zheng u64 *bytes_to_reserve) 46563fd0a558SYan, Zheng { 465710995c04SQu Wenruo struct btrfs_root *root = pending->root; 465810995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 46593fd0a558SYan, Zheng 46606282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 46613fd0a558SYan, Zheng return; 46623fd0a558SYan, Zheng 46633fd0a558SYan, Zheng if (!rc->merge_reloc_tree) 46643fd0a558SYan, Zheng return; 46653fd0a558SYan, Zheng 46663fd0a558SYan, Zheng root = root->reloc_root; 46673fd0a558SYan, Zheng BUG_ON(btrfs_root_refs(&root->root_item) == 0); 46683fd0a558SYan, Zheng /* 46693fd0a558SYan, Zheng * relocation is in the stage of merging trees. the space 46703fd0a558SYan, Zheng * used by merging a reloc tree is twice the size of 46713fd0a558SYan, Zheng * relocated tree nodes in the worst case. half for cowing 46723fd0a558SYan, Zheng * the reloc tree, half for cowing the fs tree. the space 46733fd0a558SYan, Zheng * used by cowing the reloc tree will be freed after the 46743fd0a558SYan, Zheng * tree is dropped. if we create snapshot, cowing the fs 46753fd0a558SYan, Zheng * tree may use more space than it frees. so we need 46763fd0a558SYan, Zheng * reserve extra space. 46773fd0a558SYan, Zheng */ 46783fd0a558SYan, Zheng *bytes_to_reserve += rc->nodes_relocated; 46793fd0a558SYan, Zheng } 46803fd0a558SYan, Zheng 46813fd0a558SYan, Zheng /* 46823fd0a558SYan, Zheng * called after snapshot is created. migrate block reservation 46833fd0a558SYan, Zheng * and create reloc root for the newly created snapshot 4684f44deb74SJosef Bacik * 4685f44deb74SJosef Bacik * This is similar to btrfs_init_reloc_root(), we come out of here with two 4686f44deb74SJosef Bacik * references held on the reloc_root, one for root->reloc_root and one for 4687f44deb74SJosef Bacik * rc->reloc_roots. 46883fd0a558SYan, Zheng */ 468949b25e05SJeff Mahoney int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, 46903fd0a558SYan, Zheng struct btrfs_pending_snapshot *pending) 46913fd0a558SYan, Zheng { 46923fd0a558SYan, Zheng struct btrfs_root *root = pending->root; 46933fd0a558SYan, Zheng struct btrfs_root *reloc_root; 46943fd0a558SYan, Zheng struct btrfs_root *new_root; 469510995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 46963fd0a558SYan, Zheng int ret; 46973fd0a558SYan, Zheng 46986282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 469949b25e05SJeff Mahoney return 0; 47003fd0a558SYan, Zheng 47013fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 47023fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated; 47033fd0a558SYan, Zheng 47043fd0a558SYan, Zheng if (rc->merge_reloc_tree) { 47053fd0a558SYan, Zheng ret = btrfs_block_rsv_migrate(&pending->block_rsv, 47063fd0a558SYan, Zheng rc->block_rsv, 47073a584174SLu Fengqi rc->nodes_relocated, true); 470849b25e05SJeff Mahoney if (ret) 470949b25e05SJeff Mahoney return ret; 47103fd0a558SYan, Zheng } 47113fd0a558SYan, Zheng 47123fd0a558SYan, Zheng new_root = pending->snap; 47133fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root->reloc_root, 47143fd0a558SYan, Zheng new_root->root_key.objectid); 471549b25e05SJeff Mahoney if (IS_ERR(reloc_root)) 471649b25e05SJeff Mahoney return PTR_ERR(reloc_root); 47173fd0a558SYan, Zheng 4718ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 4719ffd7b339SJeff Mahoney BUG_ON(ret < 0); 4720f44deb74SJosef Bacik new_root->reloc_root = btrfs_grab_root(reloc_root); 47213fd0a558SYan, Zheng 472249b25e05SJeff Mahoney if (rc->create_reloc_tree) 47233fd0a558SYan, Zheng ret = clone_backref_node(trans, rc, root, reloc_root); 472449b25e05SJeff Mahoney return ret; 47253fd0a558SYan, Zheng } 4726