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" 27e9a28dc5SQu Wenruo #include "misc.h" 285d4f98a2SYan Zheng 295d4f98a2SYan Zheng /* 300c891389SQu Wenruo * Relocation overview 310c891389SQu Wenruo * 320c891389SQu Wenruo * [What does relocation do] 330c891389SQu Wenruo * 340c891389SQu Wenruo * The objective of relocation is to relocate all extents of the target block 350c891389SQu Wenruo * group to other block groups. 360c891389SQu Wenruo * This is utilized by resize (shrink only), profile converting, compacting 370c891389SQu Wenruo * space, or balance routine to spread chunks over devices. 380c891389SQu Wenruo * 390c891389SQu Wenruo * Before | After 400c891389SQu Wenruo * ------------------------------------------------------------------ 410c891389SQu Wenruo * BG A: 10 data extents | BG A: deleted 420c891389SQu Wenruo * BG B: 2 data extents | BG B: 10 data extents (2 old + 8 relocated) 430c891389SQu Wenruo * BG C: 1 extents | BG C: 3 data extents (1 old + 2 relocated) 440c891389SQu Wenruo * 450c891389SQu Wenruo * [How does relocation work] 460c891389SQu Wenruo * 470c891389SQu Wenruo * 1. Mark the target block group read-only 480c891389SQu Wenruo * New extents won't be allocated from the target block group. 490c891389SQu Wenruo * 500c891389SQu Wenruo * 2.1 Record each extent in the target block group 510c891389SQu Wenruo * To build a proper map of extents to be relocated. 520c891389SQu Wenruo * 530c891389SQu Wenruo * 2.2 Build data reloc tree and reloc trees 540c891389SQu Wenruo * Data reloc tree will contain an inode, recording all newly relocated 550c891389SQu Wenruo * data extents. 560c891389SQu Wenruo * There will be only one data reloc tree for one data block group. 570c891389SQu Wenruo * 580c891389SQu Wenruo * Reloc tree will be a special snapshot of its source tree, containing 590c891389SQu Wenruo * relocated tree blocks. 600c891389SQu Wenruo * Each tree referring to a tree block in target block group will get its 610c891389SQu Wenruo * reloc tree built. 620c891389SQu Wenruo * 630c891389SQu Wenruo * 2.3 Swap source tree with its corresponding reloc tree 640c891389SQu Wenruo * Each involved tree only refers to new extents after swap. 650c891389SQu Wenruo * 660c891389SQu Wenruo * 3. Cleanup reloc trees and data reloc tree. 670c891389SQu Wenruo * As old extents in the target block group are still referenced by reloc 680c891389SQu Wenruo * trees, we need to clean them up before really freeing the target block 690c891389SQu Wenruo * group. 700c891389SQu Wenruo * 710c891389SQu Wenruo * The main complexity is in steps 2.2 and 2.3. 720c891389SQu Wenruo * 730c891389SQu Wenruo * The entry point of relocation is relocate_block_group() function. 740c891389SQu Wenruo */ 750c891389SQu Wenruo 760647bf56SWang Shilong #define RELOCATION_RESERVED_NODES 256 772a979612SQu Wenruo /* 785d4f98a2SYan Zheng * map address of tree root to tree 795d4f98a2SYan Zheng */ 805d4f98a2SYan Zheng struct mapping_node { 81e9a28dc5SQu Wenruo struct { 825d4f98a2SYan Zheng struct rb_node rb_node; 835d4f98a2SYan Zheng u64 bytenr; 84e9a28dc5SQu Wenruo }; /* Use rb_simle_node for search/insert */ 855d4f98a2SYan Zheng void *data; 865d4f98a2SYan Zheng }; 875d4f98a2SYan Zheng 885d4f98a2SYan Zheng struct mapping_tree { 895d4f98a2SYan Zheng struct rb_root rb_root; 905d4f98a2SYan Zheng spinlock_t lock; 915d4f98a2SYan Zheng }; 925d4f98a2SYan Zheng 935d4f98a2SYan Zheng /* 945d4f98a2SYan Zheng * present a tree block to process 955d4f98a2SYan Zheng */ 965d4f98a2SYan Zheng struct tree_block { 97e9a28dc5SQu Wenruo struct { 985d4f98a2SYan Zheng struct rb_node rb_node; 995d4f98a2SYan Zheng u64 bytenr; 100e9a28dc5SQu Wenruo }; /* Use rb_simple_node for search/insert */ 1015d4f98a2SYan Zheng struct btrfs_key key; 1025d4f98a2SYan Zheng unsigned int level:8; 1035d4f98a2SYan Zheng unsigned int key_ready:1; 1045d4f98a2SYan Zheng }; 1055d4f98a2SYan Zheng 1060257bb82SYan, Zheng #define MAX_EXTENTS 128 1070257bb82SYan, Zheng 1080257bb82SYan, Zheng struct file_extent_cluster { 1090257bb82SYan, Zheng u64 start; 1100257bb82SYan, Zheng u64 end; 1110257bb82SYan, Zheng u64 boundary[MAX_EXTENTS]; 1120257bb82SYan, Zheng unsigned int nr; 1130257bb82SYan, Zheng }; 1140257bb82SYan, Zheng 1155d4f98a2SYan Zheng struct reloc_control { 1165d4f98a2SYan Zheng /* block group to relocate */ 11732da5386SDavid Sterba struct btrfs_block_group *block_group; 1185d4f98a2SYan Zheng /* extent tree */ 1195d4f98a2SYan Zheng struct btrfs_root *extent_root; 1205d4f98a2SYan Zheng /* inode for moving data */ 1215d4f98a2SYan Zheng struct inode *data_inode; 1223fd0a558SYan, Zheng 1233fd0a558SYan, Zheng struct btrfs_block_rsv *block_rsv; 1243fd0a558SYan, Zheng 125a26195a5SQu Wenruo struct btrfs_backref_cache backref_cache; 1263fd0a558SYan, Zheng 1273fd0a558SYan, Zheng struct file_extent_cluster cluster; 1285d4f98a2SYan Zheng /* tree blocks have been processed */ 1295d4f98a2SYan Zheng struct extent_io_tree processed_blocks; 1305d4f98a2SYan Zheng /* map start of tree root to corresponding reloc tree */ 1315d4f98a2SYan Zheng struct mapping_tree reloc_root_tree; 1325d4f98a2SYan Zheng /* list of reloc trees */ 1335d4f98a2SYan Zheng struct list_head reloc_roots; 134d2311e69SQu Wenruo /* list of subvolume trees that get relocated */ 135d2311e69SQu Wenruo struct list_head dirty_subvol_roots; 1363fd0a558SYan, Zheng /* size of metadata reservation for merging reloc trees */ 1373fd0a558SYan, Zheng u64 merging_rsv_size; 1383fd0a558SYan, Zheng /* size of relocated tree nodes */ 1393fd0a558SYan, Zheng u64 nodes_relocated; 1400647bf56SWang Shilong /* reserved size for block group relocation*/ 1410647bf56SWang Shilong u64 reserved_bytes; 1423fd0a558SYan, Zheng 1435d4f98a2SYan Zheng u64 search_start; 1445d4f98a2SYan Zheng u64 extents_found; 1453fd0a558SYan, Zheng 1463fd0a558SYan, Zheng unsigned int stage:8; 1473fd0a558SYan, Zheng unsigned int create_reloc_tree:1; 1483fd0a558SYan, Zheng unsigned int merge_reloc_tree:1; 1495d4f98a2SYan Zheng unsigned int found_file_extent:1; 1505d4f98a2SYan Zheng }; 1515d4f98a2SYan Zheng 1525d4f98a2SYan Zheng /* stages of data relocation */ 1535d4f98a2SYan Zheng #define MOVE_DATA_EXTENTS 0 1545d4f98a2SYan Zheng #define UPDATE_DATA_PTRS 1 1555d4f98a2SYan Zheng 1569569cc20SQu Wenruo static void mark_block_processed(struct reloc_control *rc, 157a26195a5SQu Wenruo struct btrfs_backref_node *node) 1589569cc20SQu Wenruo { 1599569cc20SQu Wenruo u32 blocksize; 1609569cc20SQu Wenruo 1619569cc20SQu Wenruo if (node->level == 0 || 1629569cc20SQu Wenruo in_range(node->bytenr, rc->block_group->start, 1639569cc20SQu Wenruo rc->block_group->length)) { 1649569cc20SQu Wenruo blocksize = rc->extent_root->fs_info->nodesize; 1659569cc20SQu Wenruo set_extent_bits(&rc->processed_blocks, node->bytenr, 1669569cc20SQu Wenruo node->bytenr + blocksize - 1, EXTENT_DIRTY); 1679569cc20SQu Wenruo } 1689569cc20SQu Wenruo node->processed = 1; 1699569cc20SQu Wenruo } 1709569cc20SQu Wenruo 1715d4f98a2SYan Zheng 1725d4f98a2SYan Zheng static void mapping_tree_init(struct mapping_tree *tree) 1735d4f98a2SYan Zheng { 1746bef4d31SEric Paris tree->rb_root = RB_ROOT; 1755d4f98a2SYan Zheng spin_lock_init(&tree->lock); 1765d4f98a2SYan Zheng } 1775d4f98a2SYan Zheng 17848a3b636SEric Sandeen static void backref_tree_panic(struct rb_node *rb_node, int errno, u64 bytenr) 17943c04fb1SJeff Mahoney { 18043c04fb1SJeff Mahoney 18143c04fb1SJeff Mahoney struct btrfs_fs_info *fs_info = NULL; 182a26195a5SQu Wenruo struct btrfs_backref_node *bnode = rb_entry(rb_node, 183a26195a5SQu Wenruo struct btrfs_backref_node, rb_node); 18443c04fb1SJeff Mahoney if (bnode->root) 18543c04fb1SJeff Mahoney fs_info = bnode->root->fs_info; 1865d163e0eSJeff Mahoney btrfs_panic(fs_info, errno, 1875d163e0eSJeff Mahoney "Inconsistency in backref cache found at offset %llu", 1885d163e0eSJeff Mahoney bytenr); 18943c04fb1SJeff Mahoney } 19043c04fb1SJeff Mahoney 1915d4f98a2SYan Zheng /* 1925d4f98a2SYan Zheng * walk up backref nodes until reach node presents tree root 1935d4f98a2SYan Zheng */ 194a26195a5SQu Wenruo static struct btrfs_backref_node *walk_up_backref( 195a26195a5SQu Wenruo struct btrfs_backref_node *node, 196a26195a5SQu Wenruo struct btrfs_backref_edge *edges[], int *index) 1975d4f98a2SYan Zheng { 198a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 1995d4f98a2SYan Zheng int idx = *index; 2005d4f98a2SYan Zheng 2015d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 2025d4f98a2SYan Zheng edge = list_entry(node->upper.next, 203a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 2045d4f98a2SYan Zheng edges[idx++] = edge; 2055d4f98a2SYan Zheng node = edge->node[UPPER]; 2065d4f98a2SYan Zheng } 2073fd0a558SYan, Zheng BUG_ON(node->detached); 2085d4f98a2SYan Zheng *index = idx; 2095d4f98a2SYan Zheng return node; 2105d4f98a2SYan Zheng } 2115d4f98a2SYan Zheng 2125d4f98a2SYan Zheng /* 2135d4f98a2SYan Zheng * walk down backref nodes to find start of next reference path 2145d4f98a2SYan Zheng */ 215a26195a5SQu Wenruo static struct btrfs_backref_node *walk_down_backref( 216a26195a5SQu Wenruo struct btrfs_backref_edge *edges[], int *index) 2175d4f98a2SYan Zheng { 218a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 219a26195a5SQu Wenruo struct btrfs_backref_node *lower; 2205d4f98a2SYan Zheng int idx = *index; 2215d4f98a2SYan Zheng 2225d4f98a2SYan Zheng while (idx > 0) { 2235d4f98a2SYan Zheng edge = edges[idx - 1]; 2245d4f98a2SYan Zheng lower = edge->node[LOWER]; 2255d4f98a2SYan Zheng if (list_is_last(&edge->list[LOWER], &lower->upper)) { 2265d4f98a2SYan Zheng idx--; 2275d4f98a2SYan Zheng continue; 2285d4f98a2SYan Zheng } 2295d4f98a2SYan Zheng edge = list_entry(edge->list[LOWER].next, 230a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 2315d4f98a2SYan Zheng edges[idx - 1] = edge; 2325d4f98a2SYan Zheng *index = idx; 2335d4f98a2SYan Zheng return edge->node[UPPER]; 2345d4f98a2SYan Zheng } 2355d4f98a2SYan Zheng *index = 0; 2365d4f98a2SYan Zheng return NULL; 2375d4f98a2SYan Zheng } 2385d4f98a2SYan Zheng 239a26195a5SQu Wenruo static void update_backref_node(struct btrfs_backref_cache *cache, 240a26195a5SQu Wenruo struct btrfs_backref_node *node, u64 bytenr) 2413fd0a558SYan, Zheng { 2423fd0a558SYan, Zheng struct rb_node *rb_node; 2433fd0a558SYan, Zheng rb_erase(&node->rb_node, &cache->rb_root); 2443fd0a558SYan, Zheng node->bytenr = bytenr; 245e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, node->bytenr, &node->rb_node); 24643c04fb1SJeff Mahoney if (rb_node) 24743c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, bytenr); 2483fd0a558SYan, Zheng } 2493fd0a558SYan, Zheng 2503fd0a558SYan, Zheng /* 2513fd0a558SYan, Zheng * update backref cache after a transaction commit 2523fd0a558SYan, Zheng */ 2533fd0a558SYan, Zheng static int update_backref_cache(struct btrfs_trans_handle *trans, 254a26195a5SQu Wenruo struct btrfs_backref_cache *cache) 2553fd0a558SYan, Zheng { 256a26195a5SQu Wenruo struct btrfs_backref_node *node; 2573fd0a558SYan, Zheng int level = 0; 2583fd0a558SYan, Zheng 2593fd0a558SYan, Zheng if (cache->last_trans == 0) { 2603fd0a558SYan, Zheng cache->last_trans = trans->transid; 2613fd0a558SYan, Zheng return 0; 2623fd0a558SYan, Zheng } 2633fd0a558SYan, Zheng 2643fd0a558SYan, Zheng if (cache->last_trans == trans->transid) 2653fd0a558SYan, Zheng return 0; 2663fd0a558SYan, Zheng 2673fd0a558SYan, Zheng /* 2683fd0a558SYan, Zheng * detached nodes are used to avoid unnecessary backref 2693fd0a558SYan, Zheng * lookup. transaction commit changes the extent tree. 2703fd0a558SYan, Zheng * so the detached nodes are no longer useful. 2713fd0a558SYan, Zheng */ 2723fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 2733fd0a558SYan, Zheng node = list_entry(cache->detached.next, 274a26195a5SQu Wenruo struct btrfs_backref_node, list); 275023acb07SQu Wenruo btrfs_backref_cleanup_node(cache, node); 2763fd0a558SYan, Zheng } 2773fd0a558SYan, Zheng 2783fd0a558SYan, Zheng while (!list_empty(&cache->changed)) { 2793fd0a558SYan, Zheng node = list_entry(cache->changed.next, 280a26195a5SQu Wenruo struct btrfs_backref_node, list); 2813fd0a558SYan, Zheng list_del_init(&node->list); 2823fd0a558SYan, Zheng BUG_ON(node->pending); 2833fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 2843fd0a558SYan, Zheng } 2853fd0a558SYan, Zheng 2863fd0a558SYan, Zheng /* 2873fd0a558SYan, Zheng * some nodes can be left in the pending list if there were 2883fd0a558SYan, Zheng * errors during processing the pending nodes. 2893fd0a558SYan, Zheng */ 2903fd0a558SYan, Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 2913fd0a558SYan, Zheng list_for_each_entry(node, &cache->pending[level], list) { 2923fd0a558SYan, Zheng BUG_ON(!node->pending); 2933fd0a558SYan, Zheng if (node->bytenr == node->new_bytenr) 2943fd0a558SYan, Zheng continue; 2953fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 2963fd0a558SYan, Zheng } 2973fd0a558SYan, Zheng } 2983fd0a558SYan, Zheng 2993fd0a558SYan, Zheng cache->last_trans = 0; 3003fd0a558SYan, Zheng return 1; 3013fd0a558SYan, Zheng } 3023fd0a558SYan, Zheng 3036282675eSQu Wenruo static bool reloc_root_is_dead(struct btrfs_root *root) 3046282675eSQu Wenruo { 3056282675eSQu Wenruo /* 3066282675eSQu Wenruo * Pair with set_bit/clear_bit in clean_dirty_subvols and 3076282675eSQu Wenruo * btrfs_update_reloc_root. We need to see the updated bit before 3086282675eSQu Wenruo * trying to access reloc_root 3096282675eSQu Wenruo */ 3106282675eSQu Wenruo smp_rmb(); 3116282675eSQu Wenruo if (test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state)) 3126282675eSQu Wenruo return true; 3136282675eSQu Wenruo return false; 3146282675eSQu Wenruo } 3156282675eSQu Wenruo 3166282675eSQu Wenruo /* 3176282675eSQu Wenruo * Check if this subvolume tree has valid reloc tree. 3186282675eSQu Wenruo * 3196282675eSQu Wenruo * Reloc tree after swap is considered dead, thus not considered as valid. 3206282675eSQu Wenruo * This is enough for most callers, as they don't distinguish dead reloc root 3216282675eSQu Wenruo * from no reloc root. But should_ignore_root() below is a special case. 3226282675eSQu Wenruo */ 3236282675eSQu Wenruo static bool have_reloc_root(struct btrfs_root *root) 3246282675eSQu Wenruo { 3256282675eSQu Wenruo if (reloc_root_is_dead(root)) 3266282675eSQu Wenruo return false; 3276282675eSQu Wenruo if (!root->reloc_root) 3286282675eSQu Wenruo return false; 3296282675eSQu Wenruo return true; 3306282675eSQu Wenruo } 331f2a97a9dSDavid Sterba 3323fd0a558SYan, Zheng static int should_ignore_root(struct btrfs_root *root) 3333fd0a558SYan, Zheng { 3343fd0a558SYan, Zheng struct btrfs_root *reloc_root; 3353fd0a558SYan, Zheng 33627cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 3373fd0a558SYan, Zheng return 0; 3383fd0a558SYan, Zheng 3396282675eSQu Wenruo /* This root has been merged with its reloc tree, we can ignore it */ 3406282675eSQu Wenruo if (reloc_root_is_dead(root)) 3416282675eSQu Wenruo return 1; 3426282675eSQu Wenruo 3433fd0a558SYan, Zheng reloc_root = root->reloc_root; 3443fd0a558SYan, Zheng if (!reloc_root) 3453fd0a558SYan, Zheng return 0; 3463fd0a558SYan, Zheng 3474d4225fcSJosef Bacik if (btrfs_header_generation(reloc_root->commit_root) == 3484d4225fcSJosef Bacik root->fs_info->running_transaction->transid) 3493fd0a558SYan, Zheng return 0; 3503fd0a558SYan, Zheng /* 3513fd0a558SYan, Zheng * if there is reloc tree and it was created in previous 3523fd0a558SYan, Zheng * transaction backref lookup can find the reloc tree, 3533fd0a558SYan, Zheng * so backref node for the fs tree root is useless for 3543fd0a558SYan, Zheng * relocation. 3553fd0a558SYan, Zheng */ 3563fd0a558SYan, Zheng return 1; 3573fd0a558SYan, Zheng } 3585d4f98a2SYan Zheng /* 3595d4f98a2SYan Zheng * find reloc tree by address of tree root 3605d4f98a2SYan Zheng */ 3612433bea5SQu Wenruo struct btrfs_root *find_reloc_root(struct btrfs_fs_info *fs_info, u64 bytenr) 3625d4f98a2SYan Zheng { 3632433bea5SQu Wenruo struct reloc_control *rc = fs_info->reloc_ctl; 3645d4f98a2SYan Zheng struct rb_node *rb_node; 3655d4f98a2SYan Zheng struct mapping_node *node; 3665d4f98a2SYan Zheng struct btrfs_root *root = NULL; 3675d4f98a2SYan Zheng 3682433bea5SQu Wenruo ASSERT(rc); 3695d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 370e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, bytenr); 3715d4f98a2SYan Zheng if (rb_node) { 3725d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 3735d4f98a2SYan Zheng root = (struct btrfs_root *)node->data; 3745d4f98a2SYan Zheng } 3755d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 37600246528SJosef Bacik return btrfs_grab_root(root); 3775d4f98a2SYan Zheng } 3785d4f98a2SYan Zheng 3795d4f98a2SYan Zheng static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, 3805d4f98a2SYan Zheng u64 root_objectid) 3815d4f98a2SYan Zheng { 3825d4f98a2SYan Zheng struct btrfs_key key; 3835d4f98a2SYan Zheng 3845d4f98a2SYan Zheng key.objectid = root_objectid; 3855d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 3865d4f98a2SYan Zheng key.offset = (u64)-1; 3875d4f98a2SYan Zheng 388bc44d7c4SJosef Bacik return btrfs_get_fs_root(fs_info, &key, false); 3895d4f98a2SYan Zheng } 3905d4f98a2SYan Zheng 3915d4f98a2SYan Zheng /* 3924007ea87SQu Wenruo * Handle direct tree backref 3934007ea87SQu Wenruo * 3944007ea87SQu Wenruo * Direct tree backref means, the backref item shows its parent bytenr 3954007ea87SQu Wenruo * directly. This is for SHARED_BLOCK_REF backref (keyed or inlined). 3964007ea87SQu Wenruo * 3974007ea87SQu Wenruo * @ref_key: The converted backref key. 3984007ea87SQu Wenruo * For keyed backref, it's the item key. 3994007ea87SQu Wenruo * For inlined backref, objectid is the bytenr, 4004007ea87SQu Wenruo * type is btrfs_inline_ref_type, offset is 4014007ea87SQu Wenruo * btrfs_inline_ref_offset. 4024007ea87SQu Wenruo */ 403a26195a5SQu Wenruo static int handle_direct_tree_backref(struct btrfs_backref_cache *cache, 4044007ea87SQu Wenruo struct btrfs_key *ref_key, 405a26195a5SQu Wenruo struct btrfs_backref_node *cur) 4064007ea87SQu Wenruo { 407a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 408a26195a5SQu Wenruo struct btrfs_backref_node *upper; 4094007ea87SQu Wenruo struct rb_node *rb_node; 4104007ea87SQu Wenruo 4114007ea87SQu Wenruo ASSERT(ref_key->type == BTRFS_SHARED_BLOCK_REF_KEY); 4124007ea87SQu Wenruo 4134007ea87SQu Wenruo /* Only reloc root uses backref pointing to itself */ 4144007ea87SQu Wenruo if (ref_key->objectid == ref_key->offset) { 4154007ea87SQu Wenruo struct btrfs_root *root; 4164007ea87SQu Wenruo 4174007ea87SQu Wenruo cur->is_reloc_root = 1; 4184007ea87SQu Wenruo /* Only reloc backref cache cares about a specific root */ 4194007ea87SQu Wenruo if (cache->is_reloc) { 4204007ea87SQu Wenruo root = find_reloc_root(cache->fs_info, cur->bytenr); 4214007ea87SQu Wenruo if (WARN_ON(!root)) 4224007ea87SQu Wenruo return -ENOENT; 4234007ea87SQu Wenruo cur->root = root; 4244007ea87SQu Wenruo } else { 4254007ea87SQu Wenruo /* 4264007ea87SQu Wenruo * For generic purpose backref cache, reloc root node 4274007ea87SQu Wenruo * is useless. 4284007ea87SQu Wenruo */ 4294007ea87SQu Wenruo list_add(&cur->list, &cache->useless_node); 4304007ea87SQu Wenruo } 4314007ea87SQu Wenruo return 0; 4324007ea87SQu Wenruo } 4334007ea87SQu Wenruo 43447254d07SQu Wenruo edge = btrfs_backref_alloc_edge(cache); 4354007ea87SQu Wenruo if (!edge) 4364007ea87SQu Wenruo return -ENOMEM; 4374007ea87SQu Wenruo 438e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, ref_key->offset); 4394007ea87SQu Wenruo if (!rb_node) { 4404007ea87SQu Wenruo /* Parent node not yet cached */ 441b1818dabSQu Wenruo upper = btrfs_backref_alloc_node(cache, ref_key->offset, 4420304f2d8SQu Wenruo cur->level + 1); 4434007ea87SQu Wenruo if (!upper) { 444741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 4454007ea87SQu Wenruo return -ENOMEM; 4464007ea87SQu Wenruo } 4474007ea87SQu Wenruo 4484007ea87SQu Wenruo /* 4494007ea87SQu Wenruo * Backrefs for the upper level block isn't cached, add the 4504007ea87SQu Wenruo * block to pending list 4514007ea87SQu Wenruo */ 4524007ea87SQu Wenruo list_add_tail(&edge->list[UPPER], &cache->pending_edge); 4534007ea87SQu Wenruo } else { 4544007ea87SQu Wenruo /* Parent node already cached */ 455a26195a5SQu Wenruo upper = rb_entry(rb_node, struct btrfs_backref_node, rb_node); 4564007ea87SQu Wenruo ASSERT(upper->checked); 4574007ea87SQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 4584007ea87SQu Wenruo } 459f39911e5SQu Wenruo btrfs_backref_link_edge(edge, cur, upper, LINK_LOWER); 4604007ea87SQu Wenruo return 0; 4614007ea87SQu Wenruo } 4624007ea87SQu Wenruo 4634007ea87SQu Wenruo /* 4644d81ea8bSQu Wenruo * Handle indirect tree backref 4654d81ea8bSQu Wenruo * 4664d81ea8bSQu Wenruo * Indirect tree backref means, we only know which tree the node belongs to. 4674d81ea8bSQu Wenruo * We still need to do a tree search to find out the parents. This is for 4684d81ea8bSQu Wenruo * TREE_BLOCK_REF backref (keyed or inlined). 4694d81ea8bSQu Wenruo * 4704d81ea8bSQu Wenruo * @ref_key: The same as @ref_key in handle_direct_tree_backref() 4714d81ea8bSQu Wenruo * @tree_key: The first key of this tree block. 4724d81ea8bSQu Wenruo * @path: A clean (released) path, to avoid allocating path everytime 4734d81ea8bSQu Wenruo * the function get called. 4744d81ea8bSQu Wenruo */ 475a26195a5SQu Wenruo static int handle_indirect_tree_backref(struct btrfs_backref_cache *cache, 4764d81ea8bSQu Wenruo struct btrfs_path *path, 4774d81ea8bSQu Wenruo struct btrfs_key *ref_key, 4784d81ea8bSQu Wenruo struct btrfs_key *tree_key, 479a26195a5SQu Wenruo struct btrfs_backref_node *cur) 4804d81ea8bSQu Wenruo { 4814d81ea8bSQu Wenruo struct btrfs_fs_info *fs_info = cache->fs_info; 482a26195a5SQu Wenruo struct btrfs_backref_node *upper; 483a26195a5SQu Wenruo struct btrfs_backref_node *lower; 484a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 4854d81ea8bSQu Wenruo struct extent_buffer *eb; 4864d81ea8bSQu Wenruo struct btrfs_root *root; 4874d81ea8bSQu Wenruo struct rb_node *rb_node; 4884d81ea8bSQu Wenruo int level; 4894d81ea8bSQu Wenruo bool need_check = true; 4904d81ea8bSQu Wenruo int ret; 4914d81ea8bSQu Wenruo 4924d81ea8bSQu Wenruo root = read_fs_root(fs_info, ref_key->offset); 4934d81ea8bSQu Wenruo if (IS_ERR(root)) 4944d81ea8bSQu Wenruo return PTR_ERR(root); 4954d81ea8bSQu Wenruo if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4964d81ea8bSQu Wenruo cur->cowonly = 1; 4974d81ea8bSQu Wenruo 4984d81ea8bSQu Wenruo if (btrfs_root_level(&root->root_item) == cur->level) { 4994d81ea8bSQu Wenruo /* Tree root */ 5004d81ea8bSQu Wenruo ASSERT(btrfs_root_bytenr(&root->root_item) == cur->bytenr); 5014d81ea8bSQu Wenruo if (should_ignore_root(root)) { 5024d81ea8bSQu Wenruo btrfs_put_root(root); 5034d81ea8bSQu Wenruo list_add(&cur->list, &cache->useless_node); 5044d81ea8bSQu Wenruo } else { 5054d81ea8bSQu Wenruo cur->root = root; 5064d81ea8bSQu Wenruo } 5074d81ea8bSQu Wenruo return 0; 5084d81ea8bSQu Wenruo } 5094d81ea8bSQu Wenruo 5104d81ea8bSQu Wenruo level = cur->level + 1; 5114d81ea8bSQu Wenruo 5124d81ea8bSQu Wenruo /* Search the tree to find parent blocks referring to the block */ 5134d81ea8bSQu Wenruo path->search_commit_root = 1; 5144d81ea8bSQu Wenruo path->skip_locking = 1; 5154d81ea8bSQu Wenruo path->lowest_level = level; 5164d81ea8bSQu Wenruo ret = btrfs_search_slot(NULL, root, tree_key, path, 0, 0); 5174d81ea8bSQu Wenruo path->lowest_level = 0; 5184d81ea8bSQu Wenruo if (ret < 0) { 5194d81ea8bSQu Wenruo btrfs_put_root(root); 5204d81ea8bSQu Wenruo return ret; 5214d81ea8bSQu Wenruo } 5224d81ea8bSQu Wenruo if (ret > 0 && path->slots[level] > 0) 5234d81ea8bSQu Wenruo path->slots[level]--; 5244d81ea8bSQu Wenruo 5254d81ea8bSQu Wenruo eb = path->nodes[level]; 5264d81ea8bSQu Wenruo if (btrfs_node_blockptr(eb, path->slots[level]) != cur->bytenr) { 5274d81ea8bSQu Wenruo btrfs_err(fs_info, 5284d81ea8bSQu Wenruo "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)", 5294d81ea8bSQu Wenruo cur->bytenr, level - 1, root->root_key.objectid, 5304d81ea8bSQu Wenruo tree_key->objectid, tree_key->type, tree_key->offset); 5314d81ea8bSQu Wenruo btrfs_put_root(root); 5324d81ea8bSQu Wenruo ret = -ENOENT; 5334d81ea8bSQu Wenruo goto out; 5344d81ea8bSQu Wenruo } 5354d81ea8bSQu Wenruo lower = cur; 5364d81ea8bSQu Wenruo 5374d81ea8bSQu Wenruo /* Add all nodes and edges in the path */ 5384d81ea8bSQu Wenruo for (; level < BTRFS_MAX_LEVEL; level++) { 5394d81ea8bSQu Wenruo if (!path->nodes[level]) { 5404d81ea8bSQu Wenruo ASSERT(btrfs_root_bytenr(&root->root_item) == 5414d81ea8bSQu Wenruo lower->bytenr); 5424d81ea8bSQu Wenruo if (should_ignore_root(root)) { 5434d81ea8bSQu Wenruo btrfs_put_root(root); 5444d81ea8bSQu Wenruo list_add(&lower->list, &cache->useless_node); 5454d81ea8bSQu Wenruo } else { 5464d81ea8bSQu Wenruo lower->root = root; 5474d81ea8bSQu Wenruo } 5484d81ea8bSQu Wenruo break; 5494d81ea8bSQu Wenruo } 5504d81ea8bSQu Wenruo 55147254d07SQu Wenruo edge = btrfs_backref_alloc_edge(cache); 5524d81ea8bSQu Wenruo if (!edge) { 5534d81ea8bSQu Wenruo btrfs_put_root(root); 5544d81ea8bSQu Wenruo ret = -ENOMEM; 5554d81ea8bSQu Wenruo goto out; 5564d81ea8bSQu Wenruo } 5574d81ea8bSQu Wenruo 5584d81ea8bSQu Wenruo eb = path->nodes[level]; 559e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, eb->start); 5604d81ea8bSQu Wenruo if (!rb_node) { 561b1818dabSQu Wenruo upper = btrfs_backref_alloc_node(cache, eb->start, 5620304f2d8SQu Wenruo lower->level + 1); 5634d81ea8bSQu Wenruo if (!upper) { 5644d81ea8bSQu Wenruo btrfs_put_root(root); 565741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 5664d81ea8bSQu Wenruo ret = -ENOMEM; 5674d81ea8bSQu Wenruo goto out; 5684d81ea8bSQu Wenruo } 5694d81ea8bSQu Wenruo upper->owner = btrfs_header_owner(eb); 5704d81ea8bSQu Wenruo if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 5714d81ea8bSQu Wenruo upper->cowonly = 1; 5724d81ea8bSQu Wenruo 5734d81ea8bSQu Wenruo /* 5744d81ea8bSQu Wenruo * If we know the block isn't shared we can avoid 5754d81ea8bSQu Wenruo * checking its backrefs. 5764d81ea8bSQu Wenruo */ 5774d81ea8bSQu Wenruo if (btrfs_block_can_be_shared(root, eb)) 5784d81ea8bSQu Wenruo upper->checked = 0; 5794d81ea8bSQu Wenruo else 5804d81ea8bSQu Wenruo upper->checked = 1; 5814d81ea8bSQu Wenruo 5824d81ea8bSQu Wenruo /* 5834d81ea8bSQu Wenruo * Add the block to pending list if we need to check its 5844d81ea8bSQu Wenruo * backrefs, we only do this once while walking up a 5854d81ea8bSQu Wenruo * tree as we will catch anything else later on. 5864d81ea8bSQu Wenruo */ 5874d81ea8bSQu Wenruo if (!upper->checked && need_check) { 5884d81ea8bSQu Wenruo need_check = false; 5894d81ea8bSQu Wenruo list_add_tail(&edge->list[UPPER], 5904d81ea8bSQu Wenruo &cache->pending_edge); 5914d81ea8bSQu Wenruo } else { 5924d81ea8bSQu Wenruo if (upper->checked) 5934d81ea8bSQu Wenruo need_check = true; 5944d81ea8bSQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 5954d81ea8bSQu Wenruo } 5964d81ea8bSQu Wenruo } else { 597a26195a5SQu Wenruo upper = rb_entry(rb_node, struct btrfs_backref_node, 598a26195a5SQu Wenruo rb_node); 5994d81ea8bSQu Wenruo ASSERT(upper->checked); 6004d81ea8bSQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 6014d81ea8bSQu Wenruo if (!upper->owner) 6024d81ea8bSQu Wenruo upper->owner = btrfs_header_owner(eb); 6034d81ea8bSQu Wenruo } 604f39911e5SQu Wenruo btrfs_backref_link_edge(edge, lower, upper, LINK_LOWER); 6054d81ea8bSQu Wenruo 6064d81ea8bSQu Wenruo if (rb_node) { 6074d81ea8bSQu Wenruo btrfs_put_root(root); 6084d81ea8bSQu Wenruo break; 6094d81ea8bSQu Wenruo } 6104d81ea8bSQu Wenruo lower = upper; 6114d81ea8bSQu Wenruo upper = NULL; 6124d81ea8bSQu Wenruo } 6134d81ea8bSQu Wenruo out: 6144d81ea8bSQu Wenruo btrfs_release_path(path); 6154d81ea8bSQu Wenruo return ret; 6164d81ea8bSQu Wenruo } 6174d81ea8bSQu Wenruo 618a26195a5SQu Wenruo static int handle_one_tree_block(struct btrfs_backref_cache *cache, 619e7d571c7SQu Wenruo struct btrfs_path *path, 620e7d571c7SQu Wenruo struct btrfs_backref_iter *iter, 6215d4f98a2SYan Zheng struct btrfs_key *node_key, 622a26195a5SQu Wenruo struct btrfs_backref_node *cur) 6235d4f98a2SYan Zheng { 624e7d571c7SQu Wenruo struct btrfs_fs_info *fs_info = cache->fs_info; 625a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 626a26195a5SQu Wenruo struct btrfs_backref_node *exist; 6275d4f98a2SYan Zheng int ret; 6285d4f98a2SYan Zheng 62971f572a9SQu Wenruo ret = btrfs_backref_iter_start(iter, cur->bytenr); 630e7d571c7SQu Wenruo if (ret < 0) 631e7d571c7SQu Wenruo return ret; 63271f572a9SQu Wenruo /* 63371f572a9SQu Wenruo * We skip the first btrfs_tree_block_info, as we don't use the key 63471f572a9SQu Wenruo * stored in it, but fetch it from the tree block 63571f572a9SQu Wenruo */ 63671f572a9SQu Wenruo if (btrfs_backref_has_tree_block_info(iter)) { 63771f572a9SQu Wenruo ret = btrfs_backref_iter_next(iter); 638e7d571c7SQu Wenruo if (ret < 0) 63971f572a9SQu Wenruo goto out; 64071f572a9SQu Wenruo /* No extra backref? This means the tree block is corrupted */ 64171f572a9SQu Wenruo if (ret > 0) { 642e7d571c7SQu Wenruo ret = -EUCLEAN; 64371f572a9SQu Wenruo goto out; 64471f572a9SQu Wenruo } 64571f572a9SQu Wenruo } 6465d4f98a2SYan Zheng WARN_ON(cur->checked); 6475d4f98a2SYan Zheng if (!list_empty(&cur->upper)) { 6485d4f98a2SYan Zheng /* 64970f23fd6SJustin P. Mattock * the backref was added previously when processing 6505d4f98a2SYan Zheng * backref of type BTRFS_TREE_BLOCK_REF_KEY 6515d4f98a2SYan Zheng */ 65275bfb9afSJosef Bacik ASSERT(list_is_singular(&cur->upper)); 653a26195a5SQu Wenruo edge = list_entry(cur->upper.next, struct btrfs_backref_edge, 6545d4f98a2SYan Zheng list[LOWER]); 65575bfb9afSJosef Bacik ASSERT(list_empty(&edge->list[UPPER])); 6565d4f98a2SYan Zheng exist = edge->node[UPPER]; 6575d4f98a2SYan Zheng /* 6585d4f98a2SYan Zheng * add the upper level block to pending list if we need 6595d4f98a2SYan Zheng * check its backrefs 6605d4f98a2SYan Zheng */ 6615d4f98a2SYan Zheng if (!exist->checked) 66284780289SQu Wenruo list_add_tail(&edge->list[UPPER], &cache->pending_edge); 6635d4f98a2SYan Zheng } else { 6645d4f98a2SYan Zheng exist = NULL; 6655d4f98a2SYan Zheng } 6665d4f98a2SYan Zheng 66771f572a9SQu Wenruo for (; ret == 0; ret = btrfs_backref_iter_next(iter)) { 66871f572a9SQu Wenruo struct extent_buffer *eb; 66971f572a9SQu Wenruo struct btrfs_key key; 6703de28d57SLiu Bo int type; 67171f572a9SQu Wenruo 67271f572a9SQu Wenruo cond_resched(); 67371f572a9SQu Wenruo eb = btrfs_backref_get_eb(iter); 67471f572a9SQu Wenruo 67571f572a9SQu Wenruo key.objectid = iter->bytenr; 67671f572a9SQu Wenruo if (btrfs_backref_iter_is_inline_ref(iter)) { 67771f572a9SQu Wenruo struct btrfs_extent_inline_ref *iref; 67871f572a9SQu Wenruo 67971f572a9SQu Wenruo /* update key for inline back ref */ 68071f572a9SQu Wenruo iref = (struct btrfs_extent_inline_ref *) 68171f572a9SQu Wenruo ((unsigned long)iter->cur_ptr); 6823de28d57SLiu Bo type = btrfs_get_extent_inline_ref_type(eb, iref, 6833de28d57SLiu Bo BTRFS_REF_TYPE_BLOCK); 6843de28d57SLiu Bo if (type == BTRFS_REF_TYPE_INVALID) { 685e7d571c7SQu Wenruo ret = -EUCLEAN; 6863de28d57SLiu Bo goto out; 6873de28d57SLiu Bo } 6883de28d57SLiu Bo key.type = type; 6895d4f98a2SYan Zheng key.offset = btrfs_extent_inline_ref_offset(eb, iref); 69071f572a9SQu Wenruo } else { 69171f572a9SQu Wenruo key.type = iter->cur_key.type; 69271f572a9SQu Wenruo key.offset = iter->cur_key.offset; 6935d4f98a2SYan Zheng } 6945d4f98a2SYan Zheng 695fa6ac715SQu Wenruo /* 696fa6ac715SQu Wenruo * Parent node found and matches current inline ref, no need to 697fa6ac715SQu Wenruo * rebuild this node for this inline ref. 698fa6ac715SQu Wenruo */ 6995d4f98a2SYan Zheng if (exist && 7005d4f98a2SYan Zheng ((key.type == BTRFS_TREE_BLOCK_REF_KEY && 7015d4f98a2SYan Zheng exist->owner == key.offset) || 7025d4f98a2SYan Zheng (key.type == BTRFS_SHARED_BLOCK_REF_KEY && 7035d4f98a2SYan Zheng exist->bytenr == key.offset))) { 7045d4f98a2SYan Zheng exist = NULL; 70571f572a9SQu Wenruo continue; 7065d4f98a2SYan Zheng } 7075d4f98a2SYan Zheng 708fa6ac715SQu Wenruo /* SHARED_BLOCK_REF means key.offset is the parent bytenr */ 7095d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { 7104007ea87SQu Wenruo ret = handle_direct_tree_backref(cache, &key, cur); 711e7d571c7SQu Wenruo if (ret < 0) 7122433bea5SQu Wenruo goto out; 71371f572a9SQu Wenruo continue; 7146d8ff4e4SDavid Sterba } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) { 715e7d571c7SQu Wenruo ret = -EINVAL; 716e7d571c7SQu Wenruo btrfs_print_v0_err(fs_info); 717e7d571c7SQu Wenruo btrfs_handle_fs_error(fs_info, ret, NULL); 718ba3c2b19SNikolay Borisov goto out; 7195d4f98a2SYan Zheng } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { 72071f572a9SQu Wenruo continue; 7215d4f98a2SYan Zheng } 7225d4f98a2SYan Zheng 723fa6ac715SQu Wenruo /* 724fa6ac715SQu Wenruo * key.type == BTRFS_TREE_BLOCK_REF_KEY, inline ref offset 725fa6ac715SQu Wenruo * means the root objectid. We need to search the tree to get 726fa6ac715SQu Wenruo * its parent bytenr. 727fa6ac715SQu Wenruo */ 7284d81ea8bSQu Wenruo ret = handle_indirect_tree_backref(cache, path, &key, node_key, 7294d81ea8bSQu Wenruo cur); 730e7d571c7SQu Wenruo if (ret < 0) 73171f572a9SQu Wenruo goto out; 7325d4f98a2SYan Zheng } 73371f572a9SQu Wenruo ret = 0; 7345d4f98a2SYan Zheng cur->checked = 1; 7355d4f98a2SYan Zheng WARN_ON(exist); 736e7d571c7SQu Wenruo out: 737e7d571c7SQu Wenruo btrfs_backref_iter_release(iter); 738e7d571c7SQu Wenruo return ret; 739e7d571c7SQu Wenruo } 7405d4f98a2SYan Zheng 741e7d571c7SQu Wenruo /* 7421f872924SQu Wenruo * In handle_one_tree_backref(), we have only linked the lower node to the edge, 7431f872924SQu Wenruo * but the upper node hasn't been linked to the edge. 744a26195a5SQu Wenruo * This means we can only iterate through btrfs_backref_node::upper to reach 745a26195a5SQu Wenruo * parent edges, but not through btrfs_backref_node::lower to reach children 746a26195a5SQu Wenruo * edges. 7471f872924SQu Wenruo * 748a26195a5SQu Wenruo * This function will finish the btrfs_backref_node::lower to related edges, 749a26195a5SQu Wenruo * so that backref cache can be bi-directionally iterated. 7501f872924SQu Wenruo * 7511f872924SQu Wenruo * Also, this will add the nodes to backref cache for the next run. 7521f872924SQu Wenruo */ 753a26195a5SQu Wenruo static int finish_upper_links(struct btrfs_backref_cache *cache, 754a26195a5SQu Wenruo struct btrfs_backref_node *start) 7551f872924SQu Wenruo { 7561f872924SQu Wenruo struct list_head *useless_node = &cache->useless_node; 757a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 7581f872924SQu Wenruo struct rb_node *rb_node; 7591f872924SQu Wenruo LIST_HEAD(pending_edge); 7601f872924SQu Wenruo 7611f872924SQu Wenruo ASSERT(start->checked); 7621f872924SQu Wenruo 7631f872924SQu Wenruo /* Insert this node to cache if it's not COW-only */ 7641f872924SQu Wenruo if (!start->cowonly) { 765e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, start->bytenr, 7661f872924SQu Wenruo &start->rb_node); 7671f872924SQu Wenruo if (rb_node) 7681f872924SQu Wenruo backref_tree_panic(rb_node, -EEXIST, start->bytenr); 7691f872924SQu Wenruo list_add_tail(&start->lower, &cache->leaves); 7701f872924SQu Wenruo } 7711f872924SQu Wenruo 7721f872924SQu Wenruo /* 7731f872924SQu Wenruo * Use breadth first search to iterate all related edges. 7741f872924SQu Wenruo * 7751f872924SQu Wenruo * The starting points are all the edges of this node 7761f872924SQu Wenruo */ 7771f872924SQu Wenruo list_for_each_entry(edge, &start->upper, list[LOWER]) 7781f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &pending_edge); 7791f872924SQu Wenruo 7801f872924SQu Wenruo while (!list_empty(&pending_edge)) { 781a26195a5SQu Wenruo struct btrfs_backref_node *upper; 782a26195a5SQu Wenruo struct btrfs_backref_node *lower; 7831f872924SQu Wenruo struct rb_node *rb_node; 7841f872924SQu Wenruo 785a26195a5SQu Wenruo edge = list_first_entry(&pending_edge, 786a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 7871f872924SQu Wenruo list_del_init(&edge->list[UPPER]); 7881f872924SQu Wenruo upper = edge->node[UPPER]; 7891f872924SQu Wenruo lower = edge->node[LOWER]; 7901f872924SQu Wenruo 7911f872924SQu Wenruo /* Parent is detached, no need to keep any edges */ 7921f872924SQu Wenruo if (upper->detached) { 7931f872924SQu Wenruo list_del(&edge->list[LOWER]); 794741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 7951f872924SQu Wenruo 7961f872924SQu Wenruo /* Lower node is orphan, queue for cleanup */ 7971f872924SQu Wenruo if (list_empty(&lower->upper)) 7981f872924SQu Wenruo list_add(&lower->list, useless_node); 7991f872924SQu Wenruo continue; 8001f872924SQu Wenruo } 8011f872924SQu Wenruo 8021f872924SQu Wenruo /* 8031f872924SQu Wenruo * All new nodes added in current build_backref_tree() haven't 8041f872924SQu Wenruo * been linked to the cache rb tree. 8051f872924SQu Wenruo * So if we have upper->rb_node populated, this means a cache 8061f872924SQu Wenruo * hit. We only need to link the edge, as @upper and all its 8071f872924SQu Wenruo * parent have already been linked. 8081f872924SQu Wenruo */ 8091f872924SQu Wenruo if (!RB_EMPTY_NODE(&upper->rb_node)) { 8101f872924SQu Wenruo if (upper->lowest) { 8111f872924SQu Wenruo list_del_init(&upper->lower); 8121f872924SQu Wenruo upper->lowest = 0; 8131f872924SQu Wenruo } 8141f872924SQu Wenruo 8151f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &upper->lower); 8161f872924SQu Wenruo continue; 8171f872924SQu Wenruo } 8181f872924SQu Wenruo 8191f872924SQu Wenruo /* Sanity check, we shouldn't have any unchecked nodes */ 8201f872924SQu Wenruo if (!upper->checked) { 8211f872924SQu Wenruo ASSERT(0); 8221f872924SQu Wenruo return -EUCLEAN; 8231f872924SQu Wenruo } 8241f872924SQu Wenruo 8251f872924SQu Wenruo /* Sanity check, COW-only node has non-COW-only parent */ 8261f872924SQu Wenruo if (start->cowonly != upper->cowonly) { 8271f872924SQu Wenruo ASSERT(0); 8281f872924SQu Wenruo return -EUCLEAN; 8291f872924SQu Wenruo } 8301f872924SQu Wenruo 8311f872924SQu Wenruo /* Only cache non-COW-only (subvolume trees) tree blocks */ 8321f872924SQu Wenruo if (!upper->cowonly) { 833e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, upper->bytenr, 8341f872924SQu Wenruo &upper->rb_node); 8351f872924SQu Wenruo if (rb_node) { 8361f872924SQu Wenruo backref_tree_panic(rb_node, -EEXIST, 8371f872924SQu Wenruo upper->bytenr); 8381f872924SQu Wenruo return -EUCLEAN; 8391f872924SQu Wenruo } 8401f872924SQu Wenruo } 8411f872924SQu Wenruo 8421f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &upper->lower); 8431f872924SQu Wenruo 8441f872924SQu Wenruo /* 8451f872924SQu Wenruo * Also queue all the parent edges of this uncached node to 8461f872924SQu Wenruo * finish the upper linkage 8471f872924SQu Wenruo */ 8481f872924SQu Wenruo list_for_each_entry(edge, &upper->upper, list[LOWER]) 8491f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &pending_edge); 8501f872924SQu Wenruo } 8511f872924SQu Wenruo return 0; 8521f872924SQu Wenruo } 8531f872924SQu Wenruo 8541f872924SQu Wenruo /* 85529db137bSQu Wenruo * For useless nodes, do two major clean ups: 85629db137bSQu Wenruo * 85729db137bSQu Wenruo * - Cleanup the children edges and nodes 85829db137bSQu Wenruo * If child node is also orphan (no parent) during cleanup, then the child 85929db137bSQu Wenruo * node will also be cleaned up. 86029db137bSQu Wenruo * 86129db137bSQu Wenruo * - Freeing up leaves (level 0), keeps nodes detached 86229db137bSQu Wenruo * For nodes, the node is still cached as "detached" 86329db137bSQu Wenruo * 86429db137bSQu Wenruo * Return false if @node is not in the @useless_nodes list. 86529db137bSQu Wenruo * Return true if @node is in the @useless_nodes list. 86629db137bSQu Wenruo */ 86729db137bSQu Wenruo static bool handle_useless_nodes(struct reloc_control *rc, 868a26195a5SQu Wenruo struct btrfs_backref_node *node) 86929db137bSQu Wenruo { 870a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 87129db137bSQu Wenruo struct list_head *useless_node = &cache->useless_node; 87229db137bSQu Wenruo bool ret = false; 87329db137bSQu Wenruo 87429db137bSQu Wenruo while (!list_empty(useless_node)) { 875a26195a5SQu Wenruo struct btrfs_backref_node *cur; 87629db137bSQu Wenruo 877a26195a5SQu Wenruo cur = list_first_entry(useless_node, struct btrfs_backref_node, 87829db137bSQu Wenruo list); 87929db137bSQu Wenruo list_del_init(&cur->list); 88029db137bSQu Wenruo 88129db137bSQu Wenruo /* Only tree root nodes can be added to @useless_nodes */ 88229db137bSQu Wenruo ASSERT(list_empty(&cur->upper)); 88329db137bSQu Wenruo 88429db137bSQu Wenruo if (cur == node) 88529db137bSQu Wenruo ret = true; 88629db137bSQu Wenruo 88729db137bSQu Wenruo /* The node is the lowest node */ 88829db137bSQu Wenruo if (cur->lowest) { 88929db137bSQu Wenruo list_del_init(&cur->lower); 89029db137bSQu Wenruo cur->lowest = 0; 89129db137bSQu Wenruo } 89229db137bSQu Wenruo 89329db137bSQu Wenruo /* Cleanup the lower edges */ 89429db137bSQu Wenruo while (!list_empty(&cur->lower)) { 895a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 896a26195a5SQu Wenruo struct btrfs_backref_node *lower; 89729db137bSQu Wenruo 89829db137bSQu Wenruo edge = list_entry(cur->lower.next, 899a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 90029db137bSQu Wenruo list_del(&edge->list[UPPER]); 90129db137bSQu Wenruo list_del(&edge->list[LOWER]); 90229db137bSQu Wenruo lower = edge->node[LOWER]; 903741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 90429db137bSQu Wenruo 90529db137bSQu Wenruo /* Child node is also orphan, queue for cleanup */ 90629db137bSQu Wenruo if (list_empty(&lower->upper)) 90729db137bSQu Wenruo list_add(&lower->list, useless_node); 90829db137bSQu Wenruo } 90929db137bSQu Wenruo /* Mark this block processed for relocation */ 91029db137bSQu Wenruo mark_block_processed(rc, cur); 91129db137bSQu Wenruo 91229db137bSQu Wenruo /* 91329db137bSQu Wenruo * Backref nodes for tree leaves are deleted from the cache. 91429db137bSQu Wenruo * Backref nodes for upper level tree blocks are left in the 91529db137bSQu Wenruo * cache to avoid unnecessary backref lookup. 91629db137bSQu Wenruo */ 91729db137bSQu Wenruo if (cur->level > 0) { 91829db137bSQu Wenruo list_add(&cur->list, &cache->detached); 91929db137bSQu Wenruo cur->detached = 1; 92029db137bSQu Wenruo } else { 92129db137bSQu Wenruo rb_erase(&cur->rb_node, &cache->rb_root); 922741188d3SQu Wenruo btrfs_backref_free_node(cache, cur); 92329db137bSQu Wenruo } 92429db137bSQu Wenruo } 92529db137bSQu Wenruo return ret; 92629db137bSQu Wenruo } 92729db137bSQu Wenruo 92829db137bSQu Wenruo /* 929e7d571c7SQu Wenruo * Build backref tree for a given tree block. Root of the backref tree 930e7d571c7SQu Wenruo * corresponds the tree block, leaves of the backref tree correspond roots of 931e7d571c7SQu Wenruo * b-trees that reference the tree block. 932e7d571c7SQu Wenruo * 933e7d571c7SQu Wenruo * The basic idea of this function is check backrefs of a given block to find 934e7d571c7SQu Wenruo * upper level blocks that reference the block, and then check backrefs of 935e7d571c7SQu Wenruo * these upper level blocks recursively. The recursion stops when tree root is 936e7d571c7SQu Wenruo * reached or backrefs for the block is cached. 937e7d571c7SQu Wenruo * 938e7d571c7SQu Wenruo * NOTE: if we find that backrefs for a block are cached, we know backrefs for 939e7d571c7SQu Wenruo * all upper level blocks that directly/indirectly reference the block are also 940e7d571c7SQu Wenruo * cached. 941e7d571c7SQu Wenruo */ 942a26195a5SQu Wenruo static noinline_for_stack struct btrfs_backref_node *build_backref_tree( 943e7d571c7SQu Wenruo struct reloc_control *rc, struct btrfs_key *node_key, 944e7d571c7SQu Wenruo int level, u64 bytenr) 945e7d571c7SQu Wenruo { 946e7d571c7SQu Wenruo struct btrfs_backref_iter *iter; 947a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 948e7d571c7SQu Wenruo /* For searching parent of TREE_BLOCK_REF */ 949e7d571c7SQu Wenruo struct btrfs_path *path; 950a26195a5SQu Wenruo struct btrfs_backref_node *cur; 951a26195a5SQu Wenruo struct btrfs_backref_node *upper; 952a26195a5SQu Wenruo struct btrfs_backref_node *lower; 953a26195a5SQu Wenruo struct btrfs_backref_node *node = NULL; 954a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 955e7d571c7SQu Wenruo int ret; 956e7d571c7SQu Wenruo int err = 0; 957e7d571c7SQu Wenruo 958e7d571c7SQu Wenruo iter = btrfs_backref_iter_alloc(rc->extent_root->fs_info, GFP_NOFS); 959e7d571c7SQu Wenruo if (!iter) 960e7d571c7SQu Wenruo return ERR_PTR(-ENOMEM); 961e7d571c7SQu Wenruo path = btrfs_alloc_path(); 962e7d571c7SQu Wenruo if (!path) { 963e7d571c7SQu Wenruo err = -ENOMEM; 964e7d571c7SQu Wenruo goto out; 965e7d571c7SQu Wenruo } 966e7d571c7SQu Wenruo 967b1818dabSQu Wenruo node = btrfs_backref_alloc_node(cache, bytenr, level); 968e7d571c7SQu Wenruo if (!node) { 969e7d571c7SQu Wenruo err = -ENOMEM; 970e7d571c7SQu Wenruo goto out; 971e7d571c7SQu Wenruo } 972e7d571c7SQu Wenruo 973e7d571c7SQu Wenruo node->lowest = 1; 974e7d571c7SQu Wenruo cur = node; 975e7d571c7SQu Wenruo 976e7d571c7SQu Wenruo /* Breadth-first search to build backref cache */ 977e7d571c7SQu Wenruo do { 978e7d571c7SQu Wenruo ret = handle_one_tree_block(cache, path, iter, node_key, cur); 979e7d571c7SQu Wenruo if (ret < 0) { 980e7d571c7SQu Wenruo err = ret; 981e7d571c7SQu Wenruo goto out; 982e7d571c7SQu Wenruo } 983e7d571c7SQu Wenruo edge = list_first_entry_or_null(&cache->pending_edge, 984a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 985e7d571c7SQu Wenruo /* 986e7d571c7SQu Wenruo * The pending list isn't empty, take the first block to 987e7d571c7SQu Wenruo * process 988e7d571c7SQu Wenruo */ 989e7d571c7SQu Wenruo if (edge) { 9905d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 9915d4f98a2SYan Zheng cur = edge->node[UPPER]; 9925d4f98a2SYan Zheng } 993e7d571c7SQu Wenruo } while (edge); 9945d4f98a2SYan Zheng 9951f872924SQu Wenruo /* Finish the upper linkage of newly added edges/nodes */ 9961f872924SQu Wenruo ret = finish_upper_links(cache, node); 9971f872924SQu Wenruo if (ret < 0) { 9981f872924SQu Wenruo err = ret; 99975bfb9afSJosef Bacik goto out; 100075bfb9afSJosef Bacik } 100175bfb9afSJosef Bacik 100229db137bSQu Wenruo if (handle_useless_nodes(rc, node)) 10033fd0a558SYan, Zheng node = NULL; 10045d4f98a2SYan Zheng out: 100571f572a9SQu Wenruo btrfs_backref_iter_free(iter); 100671f572a9SQu Wenruo btrfs_free_path(path); 10075d4f98a2SYan Zheng if (err) { 100884780289SQu Wenruo while (!list_empty(&cache->useless_node)) { 100984780289SQu Wenruo lower = list_first_entry(&cache->useless_node, 1010a26195a5SQu Wenruo struct btrfs_backref_node, list); 101175bfb9afSJosef Bacik list_del_init(&lower->list); 10123fd0a558SYan, Zheng } 101384780289SQu Wenruo while (!list_empty(&cache->pending_edge)) { 101484780289SQu Wenruo edge = list_first_entry(&cache->pending_edge, 1015a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 101675bfb9afSJosef Bacik list_del(&edge->list[UPPER]); 10173fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 101875bfb9afSJosef Bacik lower = edge->node[LOWER]; 10195d4f98a2SYan Zheng upper = edge->node[UPPER]; 1020741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 102175bfb9afSJosef Bacik 102275bfb9afSJosef Bacik /* 102375bfb9afSJosef Bacik * Lower is no longer linked to any upper backref nodes 102475bfb9afSJosef Bacik * and isn't in the cache, we can free it ourselves. 102575bfb9afSJosef Bacik */ 102675bfb9afSJosef Bacik if (list_empty(&lower->upper) && 102775bfb9afSJosef Bacik RB_EMPTY_NODE(&lower->rb_node)) 102884780289SQu Wenruo list_add(&lower->list, &cache->useless_node); 102975bfb9afSJosef Bacik 103075bfb9afSJosef Bacik if (!RB_EMPTY_NODE(&upper->rb_node)) 103175bfb9afSJosef Bacik continue; 103275bfb9afSJosef Bacik 103301327610SNicholas D Steeves /* Add this guy's upper edges to the list to process */ 103475bfb9afSJosef Bacik list_for_each_entry(edge, &upper->upper, list[LOWER]) 103584780289SQu Wenruo list_add_tail(&edge->list[UPPER], 103684780289SQu Wenruo &cache->pending_edge); 103775bfb9afSJosef Bacik if (list_empty(&upper->upper)) 103884780289SQu Wenruo list_add(&upper->list, &cache->useless_node); 103975bfb9afSJosef Bacik } 104075bfb9afSJosef Bacik 104184780289SQu Wenruo while (!list_empty(&cache->useless_node)) { 104284780289SQu Wenruo lower = list_first_entry(&cache->useless_node, 1043a26195a5SQu Wenruo struct btrfs_backref_node, list); 104475bfb9afSJosef Bacik list_del_init(&lower->list); 10450fd8c3daSLiu Bo if (lower == node) 10460fd8c3daSLiu Bo node = NULL; 1047741188d3SQu Wenruo btrfs_backref_free_node(cache, lower); 10485d4f98a2SYan Zheng } 10490fd8c3daSLiu Bo 1050023acb07SQu Wenruo btrfs_backref_cleanup_node(cache, node); 105184780289SQu Wenruo ASSERT(list_empty(&cache->useless_node) && 105284780289SQu Wenruo list_empty(&cache->pending_edge)); 10535d4f98a2SYan Zheng return ERR_PTR(err); 10545d4f98a2SYan Zheng } 105575bfb9afSJosef Bacik ASSERT(!node || !node->detached); 105684780289SQu Wenruo ASSERT(list_empty(&cache->useless_node) && 105784780289SQu Wenruo list_empty(&cache->pending_edge)); 10585d4f98a2SYan Zheng return node; 10595d4f98a2SYan Zheng } 10605d4f98a2SYan Zheng 10615d4f98a2SYan Zheng /* 10623fd0a558SYan, Zheng * helper to add backref node for the newly created snapshot. 10633fd0a558SYan, Zheng * the backref node is created by cloning backref node that 10643fd0a558SYan, Zheng * corresponds to root of source tree 10653fd0a558SYan, Zheng */ 10663fd0a558SYan, Zheng static int clone_backref_node(struct btrfs_trans_handle *trans, 10673fd0a558SYan, Zheng struct reloc_control *rc, 10683fd0a558SYan, Zheng struct btrfs_root *src, 10693fd0a558SYan, Zheng struct btrfs_root *dest) 10703fd0a558SYan, Zheng { 10713fd0a558SYan, Zheng struct btrfs_root *reloc_root = src->reloc_root; 1072a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 1073a26195a5SQu Wenruo struct btrfs_backref_node *node = NULL; 1074a26195a5SQu Wenruo struct btrfs_backref_node *new_node; 1075a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 1076a26195a5SQu Wenruo struct btrfs_backref_edge *new_edge; 10773fd0a558SYan, Zheng struct rb_node *rb_node; 10783fd0a558SYan, Zheng 10793fd0a558SYan, Zheng if (cache->last_trans > 0) 10803fd0a558SYan, Zheng update_backref_cache(trans, cache); 10813fd0a558SYan, Zheng 1082e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, src->commit_root->start); 10833fd0a558SYan, Zheng if (rb_node) { 1084a26195a5SQu Wenruo node = rb_entry(rb_node, struct btrfs_backref_node, rb_node); 10853fd0a558SYan, Zheng if (node->detached) 10863fd0a558SYan, Zheng node = NULL; 10873fd0a558SYan, Zheng else 10883fd0a558SYan, Zheng BUG_ON(node->new_bytenr != reloc_root->node->start); 10893fd0a558SYan, Zheng } 10903fd0a558SYan, Zheng 10913fd0a558SYan, Zheng if (!node) { 1092e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, 10933fd0a558SYan, Zheng reloc_root->commit_root->start); 10943fd0a558SYan, Zheng if (rb_node) { 1095a26195a5SQu Wenruo node = rb_entry(rb_node, struct btrfs_backref_node, 10963fd0a558SYan, Zheng rb_node); 10973fd0a558SYan, Zheng BUG_ON(node->detached); 10983fd0a558SYan, Zheng } 10993fd0a558SYan, Zheng } 11003fd0a558SYan, Zheng 11013fd0a558SYan, Zheng if (!node) 11023fd0a558SYan, Zheng return 0; 11033fd0a558SYan, Zheng 1104b1818dabSQu Wenruo new_node = btrfs_backref_alloc_node(cache, dest->node->start, 1105b1818dabSQu Wenruo node->level); 11063fd0a558SYan, Zheng if (!new_node) 11073fd0a558SYan, Zheng return -ENOMEM; 11083fd0a558SYan, Zheng 11093fd0a558SYan, Zheng new_node->lowest = node->lowest; 11106848ad64SYan, Zheng new_node->checked = 1; 111100246528SJosef Bacik new_node->root = btrfs_grab_root(dest); 11120b530bc5SJosef Bacik ASSERT(new_node->root); 11133fd0a558SYan, Zheng 11143fd0a558SYan, Zheng if (!node->lowest) { 11153fd0a558SYan, Zheng list_for_each_entry(edge, &node->lower, list[UPPER]) { 111647254d07SQu Wenruo new_edge = btrfs_backref_alloc_edge(cache); 11173fd0a558SYan, Zheng if (!new_edge) 11183fd0a558SYan, Zheng goto fail; 11193fd0a558SYan, Zheng 1120f39911e5SQu Wenruo btrfs_backref_link_edge(new_edge, edge->node[LOWER], 1121f39911e5SQu Wenruo new_node, LINK_UPPER); 11223fd0a558SYan, Zheng } 112376b9e23dSMiao Xie } else { 112476b9e23dSMiao Xie list_add_tail(&new_node->lower, &cache->leaves); 11253fd0a558SYan, Zheng } 11263fd0a558SYan, Zheng 1127e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, new_node->bytenr, 11283fd0a558SYan, Zheng &new_node->rb_node); 112943c04fb1SJeff Mahoney if (rb_node) 113043c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, new_node->bytenr); 11313fd0a558SYan, Zheng 11323fd0a558SYan, Zheng if (!new_node->lowest) { 11333fd0a558SYan, Zheng list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) { 11343fd0a558SYan, Zheng list_add_tail(&new_edge->list[LOWER], 11353fd0a558SYan, Zheng &new_edge->node[LOWER]->upper); 11363fd0a558SYan, Zheng } 11373fd0a558SYan, Zheng } 11383fd0a558SYan, Zheng return 0; 11393fd0a558SYan, Zheng fail: 11403fd0a558SYan, Zheng while (!list_empty(&new_node->lower)) { 11413fd0a558SYan, Zheng new_edge = list_entry(new_node->lower.next, 1142a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 11433fd0a558SYan, Zheng list_del(&new_edge->list[UPPER]); 1144741188d3SQu Wenruo btrfs_backref_free_edge(cache, new_edge); 11453fd0a558SYan, Zheng } 1146741188d3SQu Wenruo btrfs_backref_free_node(cache, new_node); 11473fd0a558SYan, Zheng return -ENOMEM; 11483fd0a558SYan, Zheng } 11493fd0a558SYan, Zheng 11503fd0a558SYan, Zheng /* 11515d4f98a2SYan Zheng * helper to add 'address of tree root -> reloc tree' mapping 11525d4f98a2SYan Zheng */ 1153ffd7b339SJeff Mahoney static int __must_check __add_reloc_root(struct btrfs_root *root) 11545d4f98a2SYan Zheng { 11550b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 11565d4f98a2SYan Zheng struct rb_node *rb_node; 11575d4f98a2SYan Zheng struct mapping_node *node; 11580b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 11595d4f98a2SYan Zheng 11605d4f98a2SYan Zheng node = kmalloc(sizeof(*node), GFP_NOFS); 1161ffd7b339SJeff Mahoney if (!node) 1162ffd7b339SJeff Mahoney return -ENOMEM; 11635d4f98a2SYan Zheng 1164ea287ab1SJosef Bacik node->bytenr = root->commit_root->start; 11655d4f98a2SYan Zheng node->data = root; 11665d4f98a2SYan Zheng 11675d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1168e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&rc->reloc_root_tree.rb_root, 11695d4f98a2SYan Zheng node->bytenr, &node->rb_node); 11705d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 1171ffd7b339SJeff Mahoney if (rb_node) { 11720b246afaSJeff Mahoney btrfs_panic(fs_info, -EEXIST, 11735d163e0eSJeff Mahoney "Duplicate root found for start=%llu while inserting into relocation tree", 11745d163e0eSJeff Mahoney node->bytenr); 1175ffd7b339SJeff Mahoney } 11765d4f98a2SYan Zheng 11775d4f98a2SYan Zheng list_add_tail(&root->root_list, &rc->reloc_roots); 11785d4f98a2SYan Zheng return 0; 11795d4f98a2SYan Zheng } 11805d4f98a2SYan Zheng 11815d4f98a2SYan Zheng /* 1182c974c464SWang Shilong * helper to delete the 'address of tree root -> reloc tree' 11835d4f98a2SYan Zheng * mapping 11845d4f98a2SYan Zheng */ 1185c974c464SWang Shilong static void __del_reloc_root(struct btrfs_root *root) 11865d4f98a2SYan Zheng { 11870b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 11885d4f98a2SYan Zheng struct rb_node *rb_node; 11895d4f98a2SYan Zheng struct mapping_node *node = NULL; 11900b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1191f44deb74SJosef Bacik bool put_ref = false; 11925d4f98a2SYan Zheng 119365c6e82bSQu Wenruo if (rc && root->node) { 11945d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1195e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, 1196ea287ab1SJosef Bacik root->commit_root->start); 1197c974c464SWang Shilong if (rb_node) { 1198c974c464SWang Shilong node = rb_entry(rb_node, struct mapping_node, rb_node); 1199c974c464SWang Shilong rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 1200ea287ab1SJosef Bacik RB_CLEAR_NODE(&node->rb_node); 1201c974c464SWang Shilong } 1202c974c464SWang Shilong spin_unlock(&rc->reloc_root_tree.lock); 1203c974c464SWang Shilong if (!node) 1204c974c464SWang Shilong return; 1205c974c464SWang Shilong BUG_ON((struct btrfs_root *)node->data != root); 1206389305b2SQu Wenruo } 1207c974c464SWang Shilong 1208f44deb74SJosef Bacik /* 1209f44deb74SJosef Bacik * We only put the reloc root here if it's on the list. There's a lot 1210f44deb74SJosef Bacik * of places where the pattern is to splice the rc->reloc_roots, process 1211f44deb74SJosef Bacik * the reloc roots, and then add the reloc root back onto 1212f44deb74SJosef Bacik * rc->reloc_roots. If we call __del_reloc_root while it's off of the 1213f44deb74SJosef Bacik * list we don't want the reference being dropped, because the guy 1214f44deb74SJosef Bacik * messing with the list is in charge of the reference. 1215f44deb74SJosef Bacik */ 12160b246afaSJeff Mahoney spin_lock(&fs_info->trans_lock); 1217f44deb74SJosef Bacik if (!list_empty(&root->root_list)) { 1218f44deb74SJosef Bacik put_ref = true; 1219c974c464SWang Shilong list_del_init(&root->root_list); 1220f44deb74SJosef Bacik } 12210b246afaSJeff Mahoney spin_unlock(&fs_info->trans_lock); 1222f44deb74SJosef Bacik if (put_ref) 1223f44deb74SJosef Bacik btrfs_put_root(root); 1224c974c464SWang Shilong kfree(node); 1225c974c464SWang Shilong } 1226c974c464SWang Shilong 1227c974c464SWang Shilong /* 1228c974c464SWang Shilong * helper to update the 'address of tree root -> reloc tree' 1229c974c464SWang Shilong * mapping 1230c974c464SWang Shilong */ 1231ea287ab1SJosef Bacik static int __update_reloc_root(struct btrfs_root *root) 1232c974c464SWang Shilong { 12330b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 1234c974c464SWang Shilong struct rb_node *rb_node; 1235c974c464SWang Shilong struct mapping_node *node = NULL; 12360b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1237c974c464SWang Shilong 1238c974c464SWang Shilong spin_lock(&rc->reloc_root_tree.lock); 1239e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, 1240ea287ab1SJosef Bacik root->commit_root->start); 12415d4f98a2SYan Zheng if (rb_node) { 12425d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 12435d4f98a2SYan Zheng rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 12445d4f98a2SYan Zheng } 12455d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 12465d4f98a2SYan Zheng 12478f71f3e0SLiu Bo if (!node) 12488f71f3e0SLiu Bo return 0; 12495d4f98a2SYan Zheng BUG_ON((struct btrfs_root *)node->data != root); 12505d4f98a2SYan Zheng 12515d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1252ea287ab1SJosef Bacik node->bytenr = root->node->start; 1253e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&rc->reloc_root_tree.rb_root, 12545d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12555d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 125643c04fb1SJeff Mahoney if (rb_node) 125743c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, node->bytenr); 12585d4f98a2SYan Zheng return 0; 12595d4f98a2SYan Zheng } 12605d4f98a2SYan Zheng 12613fd0a558SYan, Zheng static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, 12623fd0a558SYan, Zheng struct btrfs_root *root, u64 objectid) 12635d4f98a2SYan Zheng { 12640b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12655d4f98a2SYan Zheng struct btrfs_root *reloc_root; 12665d4f98a2SYan Zheng struct extent_buffer *eb; 12675d4f98a2SYan Zheng struct btrfs_root_item *root_item; 12685d4f98a2SYan Zheng struct btrfs_key root_key; 12695d4f98a2SYan Zheng int ret; 12705d4f98a2SYan Zheng 12715d4f98a2SYan Zheng root_item = kmalloc(sizeof(*root_item), GFP_NOFS); 12725d4f98a2SYan Zheng BUG_ON(!root_item); 12735d4f98a2SYan Zheng 12745d4f98a2SYan Zheng root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; 12755d4f98a2SYan Zheng root_key.type = BTRFS_ROOT_ITEM_KEY; 12763fd0a558SYan, Zheng root_key.offset = objectid; 12775d4f98a2SYan Zheng 12783fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 1279054570a1SFilipe Manana u64 commit_root_gen; 1280054570a1SFilipe Manana 12813fd0a558SYan, Zheng /* called by btrfs_init_reloc_root */ 12825d4f98a2SYan Zheng ret = btrfs_copy_root(trans, root, root->commit_root, &eb, 12835d4f98a2SYan Zheng BTRFS_TREE_RELOC_OBJECTID); 12845d4f98a2SYan Zheng BUG_ON(ret); 1285054570a1SFilipe Manana /* 1286054570a1SFilipe Manana * Set the last_snapshot field to the generation of the commit 1287054570a1SFilipe Manana * root - like this ctree.c:btrfs_block_can_be_shared() behaves 1288054570a1SFilipe Manana * correctly (returns true) when the relocation root is created 1289054570a1SFilipe Manana * either inside the critical section of a transaction commit 1290054570a1SFilipe Manana * (through transaction.c:qgroup_account_snapshot()) and when 1291054570a1SFilipe Manana * it's created before the transaction commit is started. 1292054570a1SFilipe Manana */ 1293054570a1SFilipe Manana commit_root_gen = btrfs_header_generation(root->commit_root); 1294054570a1SFilipe Manana btrfs_set_root_last_snapshot(&root->root_item, commit_root_gen); 12953fd0a558SYan, Zheng } else { 12963fd0a558SYan, Zheng /* 12973fd0a558SYan, Zheng * called by btrfs_reloc_post_snapshot_hook. 12983fd0a558SYan, Zheng * the source tree is a reloc tree, all tree blocks 12993fd0a558SYan, Zheng * modified after it was created have RELOC flag 13003fd0a558SYan, Zheng * set in their headers. so it's OK to not update 13013fd0a558SYan, Zheng * the 'last_snapshot'. 13023fd0a558SYan, Zheng */ 13033fd0a558SYan, Zheng ret = btrfs_copy_root(trans, root, root->node, &eb, 13043fd0a558SYan, Zheng BTRFS_TREE_RELOC_OBJECTID); 13053fd0a558SYan, Zheng BUG_ON(ret); 13063fd0a558SYan, Zheng } 13073fd0a558SYan, Zheng 13085d4f98a2SYan Zheng memcpy(root_item, &root->root_item, sizeof(*root_item)); 13095d4f98a2SYan Zheng btrfs_set_root_bytenr(root_item, eb->start); 13105d4f98a2SYan Zheng btrfs_set_root_level(root_item, btrfs_header_level(eb)); 13115d4f98a2SYan Zheng btrfs_set_root_generation(root_item, trans->transid); 13123fd0a558SYan, Zheng 13133fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 13143fd0a558SYan, Zheng btrfs_set_root_refs(root_item, 0); 13153fd0a558SYan, Zheng memset(&root_item->drop_progress, 0, 13163fd0a558SYan, Zheng sizeof(struct btrfs_disk_key)); 13175d4f98a2SYan Zheng root_item->drop_level = 0; 13183fd0a558SYan, Zheng } 13195d4f98a2SYan Zheng 13205d4f98a2SYan Zheng btrfs_tree_unlock(eb); 13215d4f98a2SYan Zheng free_extent_buffer(eb); 13225d4f98a2SYan Zheng 13230b246afaSJeff Mahoney ret = btrfs_insert_root(trans, fs_info->tree_root, 13245d4f98a2SYan Zheng &root_key, root_item); 13255d4f98a2SYan Zheng BUG_ON(ret); 13265d4f98a2SYan Zheng kfree(root_item); 13275d4f98a2SYan Zheng 13283dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(fs_info->tree_root, &root_key); 13295d4f98a2SYan Zheng BUG_ON(IS_ERR(reloc_root)); 13303dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 13315d4f98a2SYan Zheng reloc_root->last_trans = trans->transid; 13323fd0a558SYan, Zheng return reloc_root; 13333fd0a558SYan, Zheng } 13343fd0a558SYan, Zheng 13353fd0a558SYan, Zheng /* 13363fd0a558SYan, Zheng * create reloc tree for a given fs tree. reloc tree is just a 13373fd0a558SYan, Zheng * snapshot of the fs tree with special root objectid. 1338f44deb74SJosef Bacik * 1339f44deb74SJosef Bacik * The reloc_root comes out of here with two references, one for 1340f44deb74SJosef Bacik * root->reloc_root, and another for being on the rc->reloc_roots list. 13413fd0a558SYan, Zheng */ 13423fd0a558SYan, Zheng int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, 13433fd0a558SYan, Zheng struct btrfs_root *root) 13443fd0a558SYan, Zheng { 13450b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 13463fd0a558SYan, Zheng struct btrfs_root *reloc_root; 13470b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 134820dd2cbfSMiao Xie struct btrfs_block_rsv *rsv; 13493fd0a558SYan, Zheng int clear_rsv = 0; 1350ffd7b339SJeff Mahoney int ret; 13513fd0a558SYan, Zheng 1352aec7db3bSJosef Bacik if (!rc) 13532abc726aSJosef Bacik return 0; 13542abc726aSJosef Bacik 13551fac4a54SQu Wenruo /* 13561fac4a54SQu Wenruo * The subvolume has reloc tree but the swap is finished, no need to 13571fac4a54SQu Wenruo * create/update the dead reloc tree 13581fac4a54SQu Wenruo */ 13596282675eSQu Wenruo if (reloc_root_is_dead(root)) 13601fac4a54SQu Wenruo return 0; 13611fac4a54SQu Wenruo 1362aec7db3bSJosef Bacik /* 1363aec7db3bSJosef Bacik * This is subtle but important. We do not do 1364aec7db3bSJosef Bacik * record_root_in_transaction for reloc roots, instead we record their 1365aec7db3bSJosef Bacik * corresponding fs root, and then here we update the last trans for the 1366aec7db3bSJosef Bacik * reloc root. This means that we have to do this for the entire life 1367aec7db3bSJosef Bacik * of the reloc root, regardless of which stage of the relocation we are 1368aec7db3bSJosef Bacik * in. 1369aec7db3bSJosef Bacik */ 13703fd0a558SYan, Zheng if (root->reloc_root) { 13713fd0a558SYan, Zheng reloc_root = root->reloc_root; 13723fd0a558SYan, Zheng reloc_root->last_trans = trans->transid; 13733fd0a558SYan, Zheng return 0; 13743fd0a558SYan, Zheng } 13753fd0a558SYan, Zheng 1376aec7db3bSJosef Bacik /* 1377aec7db3bSJosef Bacik * We are merging reloc roots, we do not need new reloc trees. Also 1378aec7db3bSJosef Bacik * reloc trees never need their own reloc tree. 1379aec7db3bSJosef Bacik */ 1380aec7db3bSJosef Bacik if (!rc->create_reloc_tree || 1381aec7db3bSJosef Bacik root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 1382aec7db3bSJosef Bacik return 0; 1383aec7db3bSJosef Bacik 138420dd2cbfSMiao Xie if (!trans->reloc_reserved) { 138520dd2cbfSMiao Xie rsv = trans->block_rsv; 13863fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 13873fd0a558SYan, Zheng clear_rsv = 1; 13883fd0a558SYan, Zheng } 13893fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root, root->root_key.objectid); 13903fd0a558SYan, Zheng if (clear_rsv) 139120dd2cbfSMiao Xie trans->block_rsv = rsv; 13925d4f98a2SYan Zheng 1393ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 1394ffd7b339SJeff Mahoney BUG_ON(ret < 0); 1395f44deb74SJosef Bacik root->reloc_root = btrfs_grab_root(reloc_root); 13965d4f98a2SYan Zheng return 0; 13975d4f98a2SYan Zheng } 13985d4f98a2SYan Zheng 13995d4f98a2SYan Zheng /* 14005d4f98a2SYan Zheng * update root item of reloc tree 14015d4f98a2SYan Zheng */ 14025d4f98a2SYan Zheng int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, 14035d4f98a2SYan Zheng struct btrfs_root *root) 14045d4f98a2SYan Zheng { 14050b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 14065d4f98a2SYan Zheng struct btrfs_root *reloc_root; 14075d4f98a2SYan Zheng struct btrfs_root_item *root_item; 14085d4f98a2SYan Zheng int ret; 14095d4f98a2SYan Zheng 14106282675eSQu Wenruo if (!have_reloc_root(root)) 14117585717fSChris Mason goto out; 14125d4f98a2SYan Zheng 14135d4f98a2SYan Zheng reloc_root = root->reloc_root; 14145d4f98a2SYan Zheng root_item = &reloc_root->root_item; 14155d4f98a2SYan Zheng 1416f44deb74SJosef Bacik /* 1417f44deb74SJosef Bacik * We are probably ok here, but __del_reloc_root() will drop its ref of 1418f44deb74SJosef Bacik * the root. We have the ref for root->reloc_root, but just in case 1419f44deb74SJosef Bacik * hold it while we update the reloc root. 1420f44deb74SJosef Bacik */ 1421f44deb74SJosef Bacik btrfs_grab_root(reloc_root); 1422f44deb74SJosef Bacik 1423d2311e69SQu Wenruo /* root->reloc_root will stay until current relocation finished */ 14240b246afaSJeff Mahoney if (fs_info->reloc_ctl->merge_reloc_tree && 14253fd0a558SYan, Zheng btrfs_root_refs(root_item) == 0) { 1426d2311e69SQu Wenruo set_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 14276282675eSQu Wenruo /* 14286282675eSQu Wenruo * Mark the tree as dead before we change reloc_root so 14296282675eSQu Wenruo * have_reloc_root will not touch it from now on. 14306282675eSQu Wenruo */ 14316282675eSQu Wenruo smp_wmb(); 1432c974c464SWang Shilong __del_reloc_root(reloc_root); 14335d4f98a2SYan Zheng } 14345d4f98a2SYan Zheng 14355d4f98a2SYan Zheng if (reloc_root->commit_root != reloc_root->node) { 1436ea287ab1SJosef Bacik __update_reloc_root(reloc_root); 14375d4f98a2SYan Zheng btrfs_set_root_node(root_item, reloc_root->node); 14385d4f98a2SYan Zheng free_extent_buffer(reloc_root->commit_root); 14395d4f98a2SYan Zheng reloc_root->commit_root = btrfs_root_node(reloc_root); 14405d4f98a2SYan Zheng } 14415d4f98a2SYan Zheng 14420b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 14435d4f98a2SYan Zheng &reloc_root->root_key, root_item); 14445d4f98a2SYan Zheng BUG_ON(ret); 1445f44deb74SJosef Bacik btrfs_put_root(reloc_root); 14467585717fSChris Mason out: 14475d4f98a2SYan Zheng return 0; 14485d4f98a2SYan Zheng } 14495d4f98a2SYan Zheng 14505d4f98a2SYan Zheng /* 14515d4f98a2SYan Zheng * helper to find first cached inode with inode number >= objectid 14525d4f98a2SYan Zheng * in a subvolume 14535d4f98a2SYan Zheng */ 14545d4f98a2SYan Zheng static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) 14555d4f98a2SYan Zheng { 14565d4f98a2SYan Zheng struct rb_node *node; 14575d4f98a2SYan Zheng struct rb_node *prev; 14585d4f98a2SYan Zheng struct btrfs_inode *entry; 14595d4f98a2SYan Zheng struct inode *inode; 14605d4f98a2SYan Zheng 14615d4f98a2SYan Zheng spin_lock(&root->inode_lock); 14625d4f98a2SYan Zheng again: 14635d4f98a2SYan Zheng node = root->inode_tree.rb_node; 14645d4f98a2SYan Zheng prev = NULL; 14655d4f98a2SYan Zheng while (node) { 14665d4f98a2SYan Zheng prev = node; 14675d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 14685d4f98a2SYan Zheng 14694a0cc7caSNikolay Borisov if (objectid < btrfs_ino(entry)) 14705d4f98a2SYan Zheng node = node->rb_left; 14714a0cc7caSNikolay Borisov else if (objectid > btrfs_ino(entry)) 14725d4f98a2SYan Zheng node = node->rb_right; 14735d4f98a2SYan Zheng else 14745d4f98a2SYan Zheng break; 14755d4f98a2SYan Zheng } 14765d4f98a2SYan Zheng if (!node) { 14775d4f98a2SYan Zheng while (prev) { 14785d4f98a2SYan Zheng entry = rb_entry(prev, struct btrfs_inode, rb_node); 14794a0cc7caSNikolay Borisov if (objectid <= btrfs_ino(entry)) { 14805d4f98a2SYan Zheng node = prev; 14815d4f98a2SYan Zheng break; 14825d4f98a2SYan Zheng } 14835d4f98a2SYan Zheng prev = rb_next(prev); 14845d4f98a2SYan Zheng } 14855d4f98a2SYan Zheng } 14865d4f98a2SYan Zheng while (node) { 14875d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 14885d4f98a2SYan Zheng inode = igrab(&entry->vfs_inode); 14895d4f98a2SYan Zheng if (inode) { 14905d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 14915d4f98a2SYan Zheng return inode; 14925d4f98a2SYan Zheng } 14935d4f98a2SYan Zheng 14944a0cc7caSNikolay Borisov objectid = btrfs_ino(entry) + 1; 14955d4f98a2SYan Zheng if (cond_resched_lock(&root->inode_lock)) 14965d4f98a2SYan Zheng goto again; 14975d4f98a2SYan Zheng 14985d4f98a2SYan Zheng node = rb_next(node); 14995d4f98a2SYan Zheng } 15005d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 15015d4f98a2SYan Zheng return NULL; 15025d4f98a2SYan Zheng } 15035d4f98a2SYan Zheng 15045d4f98a2SYan Zheng /* 15055d4f98a2SYan Zheng * get new location of data 15065d4f98a2SYan Zheng */ 15075d4f98a2SYan Zheng static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, 15085d4f98a2SYan Zheng u64 bytenr, u64 num_bytes) 15095d4f98a2SYan Zheng { 15105d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(reloc_inode)->root; 15115d4f98a2SYan Zheng struct btrfs_path *path; 15125d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 15135d4f98a2SYan Zheng struct extent_buffer *leaf; 15145d4f98a2SYan Zheng int ret; 15155d4f98a2SYan Zheng 15165d4f98a2SYan Zheng path = btrfs_alloc_path(); 15175d4f98a2SYan Zheng if (!path) 15185d4f98a2SYan Zheng return -ENOMEM; 15195d4f98a2SYan Zheng 15205d4f98a2SYan Zheng bytenr -= BTRFS_I(reloc_inode)->index_cnt; 1521f85b7379SDavid Sterba ret = btrfs_lookup_file_extent(NULL, root, path, 1522f85b7379SDavid Sterba btrfs_ino(BTRFS_I(reloc_inode)), bytenr, 0); 15235d4f98a2SYan Zheng if (ret < 0) 15245d4f98a2SYan Zheng goto out; 15255d4f98a2SYan Zheng if (ret > 0) { 15265d4f98a2SYan Zheng ret = -ENOENT; 15275d4f98a2SYan Zheng goto out; 15285d4f98a2SYan Zheng } 15295d4f98a2SYan Zheng 15305d4f98a2SYan Zheng leaf = path->nodes[0]; 15315d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, path->slots[0], 15325d4f98a2SYan Zheng struct btrfs_file_extent_item); 15335d4f98a2SYan Zheng 15345d4f98a2SYan Zheng BUG_ON(btrfs_file_extent_offset(leaf, fi) || 15355d4f98a2SYan Zheng btrfs_file_extent_compression(leaf, fi) || 15365d4f98a2SYan Zheng btrfs_file_extent_encryption(leaf, fi) || 15375d4f98a2SYan Zheng btrfs_file_extent_other_encoding(leaf, fi)); 15385d4f98a2SYan Zheng 15395d4f98a2SYan Zheng if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { 154083d4cfd4SJosef Bacik ret = -EINVAL; 15415d4f98a2SYan Zheng goto out; 15425d4f98a2SYan Zheng } 15435d4f98a2SYan Zheng 15445d4f98a2SYan Zheng *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 15455d4f98a2SYan Zheng ret = 0; 15465d4f98a2SYan Zheng out: 15475d4f98a2SYan Zheng btrfs_free_path(path); 15485d4f98a2SYan Zheng return ret; 15495d4f98a2SYan Zheng } 15505d4f98a2SYan Zheng 15515d4f98a2SYan Zheng /* 15525d4f98a2SYan Zheng * update file extent items in the tree leaf to point to 15535d4f98a2SYan Zheng * the new locations. 15545d4f98a2SYan Zheng */ 15553fd0a558SYan, Zheng static noinline_for_stack 15563fd0a558SYan, Zheng int replace_file_extents(struct btrfs_trans_handle *trans, 15575d4f98a2SYan Zheng struct reloc_control *rc, 15585d4f98a2SYan Zheng struct btrfs_root *root, 15593fd0a558SYan, Zheng struct extent_buffer *leaf) 15605d4f98a2SYan Zheng { 15610b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 15625d4f98a2SYan Zheng struct btrfs_key key; 15635d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 15645d4f98a2SYan Zheng struct inode *inode = NULL; 15655d4f98a2SYan Zheng u64 parent; 15665d4f98a2SYan Zheng u64 bytenr; 15673fd0a558SYan, Zheng u64 new_bytenr = 0; 15685d4f98a2SYan Zheng u64 num_bytes; 15695d4f98a2SYan Zheng u64 end; 15705d4f98a2SYan Zheng u32 nritems; 15715d4f98a2SYan Zheng u32 i; 157283d4cfd4SJosef Bacik int ret = 0; 15735d4f98a2SYan Zheng int first = 1; 15745d4f98a2SYan Zheng int dirty = 0; 15755d4f98a2SYan Zheng 15765d4f98a2SYan Zheng if (rc->stage != UPDATE_DATA_PTRS) 15775d4f98a2SYan Zheng return 0; 15785d4f98a2SYan Zheng 15795d4f98a2SYan Zheng /* reloc trees always use full backref */ 15805d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 15815d4f98a2SYan Zheng parent = leaf->start; 15825d4f98a2SYan Zheng else 15835d4f98a2SYan Zheng parent = 0; 15845d4f98a2SYan Zheng 15855d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 15865d4f98a2SYan Zheng for (i = 0; i < nritems; i++) { 158782fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 158882fa113fSQu Wenruo 15895d4f98a2SYan Zheng cond_resched(); 15905d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, i); 15915d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_DATA_KEY) 15925d4f98a2SYan Zheng continue; 15935d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 15945d4f98a2SYan Zheng if (btrfs_file_extent_type(leaf, fi) == 15955d4f98a2SYan Zheng BTRFS_FILE_EXTENT_INLINE) 15965d4f98a2SYan Zheng continue; 15975d4f98a2SYan Zheng bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 15985d4f98a2SYan Zheng num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); 15995d4f98a2SYan Zheng if (bytenr == 0) 16005d4f98a2SYan Zheng continue; 16019569cc20SQu Wenruo if (!in_range(bytenr, rc->block_group->start, 16029569cc20SQu Wenruo rc->block_group->length)) 16035d4f98a2SYan Zheng continue; 16045d4f98a2SYan Zheng 16055d4f98a2SYan Zheng /* 16065d4f98a2SYan Zheng * if we are modifying block in fs tree, wait for readpage 16075d4f98a2SYan Zheng * to complete and drop the extent cache 16085d4f98a2SYan Zheng */ 16095d4f98a2SYan Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 16105d4f98a2SYan Zheng if (first) { 16115d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 16125d4f98a2SYan Zheng first = 0; 16134a0cc7caSNikolay Borisov } else if (inode && btrfs_ino(BTRFS_I(inode)) < key.objectid) { 16143fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 16155d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 16165d4f98a2SYan Zheng } 16174a0cc7caSNikolay Borisov if (inode && btrfs_ino(BTRFS_I(inode)) == key.objectid) { 16185d4f98a2SYan Zheng end = key.offset + 16195d4f98a2SYan Zheng btrfs_file_extent_num_bytes(leaf, fi); 16205d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(key.offset, 16210b246afaSJeff Mahoney fs_info->sectorsize)); 16220b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 16235d4f98a2SYan Zheng end--; 16245d4f98a2SYan Zheng ret = try_lock_extent(&BTRFS_I(inode)->io_tree, 1625d0082371SJeff Mahoney key.offset, end); 16265d4f98a2SYan Zheng if (!ret) 16275d4f98a2SYan Zheng continue; 16285d4f98a2SYan Zheng 1629dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), 1630dcdbc059SNikolay Borisov key.offset, end, 1); 16315d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 1632d0082371SJeff Mahoney key.offset, end); 16335d4f98a2SYan Zheng } 16345d4f98a2SYan Zheng } 16355d4f98a2SYan Zheng 16365d4f98a2SYan Zheng ret = get_new_location(rc->data_inode, &new_bytenr, 16375d4f98a2SYan Zheng bytenr, num_bytes); 163883d4cfd4SJosef Bacik if (ret) { 163983d4cfd4SJosef Bacik /* 164083d4cfd4SJosef Bacik * Don't have to abort since we've not changed anything 164183d4cfd4SJosef Bacik * in the file extent yet. 164283d4cfd4SJosef Bacik */ 164383d4cfd4SJosef Bacik break; 16443fd0a558SYan, Zheng } 16455d4f98a2SYan Zheng 16465d4f98a2SYan Zheng btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); 16475d4f98a2SYan Zheng dirty = 1; 16485d4f98a2SYan Zheng 16495d4f98a2SYan Zheng key.offset -= btrfs_file_extent_offset(leaf, fi); 165082fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 165182fa113fSQu Wenruo num_bytes, parent); 165282fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 165382fa113fSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1654b06c4bf5SFilipe Manana key.objectid, key.offset); 165582fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 165683d4cfd4SJosef Bacik if (ret) { 165766642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 165883d4cfd4SJosef Bacik break; 165983d4cfd4SJosef Bacik } 16605d4f98a2SYan Zheng 1661ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr, 1662ffd4bb2aSQu Wenruo num_bytes, parent); 1663ffd4bb2aSQu Wenruo ref.real_root = root->root_key.objectid; 1664ffd4bb2aSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1665b06c4bf5SFilipe Manana key.objectid, key.offset); 1666ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 166783d4cfd4SJosef Bacik if (ret) { 166866642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 166983d4cfd4SJosef Bacik break; 167083d4cfd4SJosef Bacik } 16715d4f98a2SYan Zheng } 16725d4f98a2SYan Zheng if (dirty) 16735d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 16743fd0a558SYan, Zheng if (inode) 16753fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 167683d4cfd4SJosef Bacik return ret; 16775d4f98a2SYan Zheng } 16785d4f98a2SYan Zheng 16795d4f98a2SYan Zheng static noinline_for_stack 16805d4f98a2SYan Zheng int memcmp_node_keys(struct extent_buffer *eb, int slot, 16815d4f98a2SYan Zheng struct btrfs_path *path, int level) 16825d4f98a2SYan Zheng { 16835d4f98a2SYan Zheng struct btrfs_disk_key key1; 16845d4f98a2SYan Zheng struct btrfs_disk_key key2; 16855d4f98a2SYan Zheng btrfs_node_key(eb, &key1, slot); 16865d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &key2, path->slots[level]); 16875d4f98a2SYan Zheng return memcmp(&key1, &key2, sizeof(key1)); 16885d4f98a2SYan Zheng } 16895d4f98a2SYan Zheng 16905d4f98a2SYan Zheng /* 16915d4f98a2SYan Zheng * try to replace tree blocks in fs tree with the new blocks 16925d4f98a2SYan Zheng * in reloc tree. tree blocks haven't been modified since the 16935d4f98a2SYan Zheng * reloc tree was create can be replaced. 16945d4f98a2SYan Zheng * 16955d4f98a2SYan Zheng * if a block was replaced, level of the block + 1 is returned. 16965d4f98a2SYan Zheng * if no block got replaced, 0 is returned. if there are other 16975d4f98a2SYan Zheng * errors, a negative error number is returned. 16985d4f98a2SYan Zheng */ 16993fd0a558SYan, Zheng static noinline_for_stack 17003d0174f7SQu Wenruo int replace_path(struct btrfs_trans_handle *trans, struct reloc_control *rc, 17015d4f98a2SYan Zheng struct btrfs_root *dest, struct btrfs_root *src, 17025d4f98a2SYan Zheng struct btrfs_path *path, struct btrfs_key *next_key, 17035d4f98a2SYan Zheng int lowest_level, int max_level) 17045d4f98a2SYan Zheng { 17050b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = dest->fs_info; 17065d4f98a2SYan Zheng struct extent_buffer *eb; 17075d4f98a2SYan Zheng struct extent_buffer *parent; 170882fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 17095d4f98a2SYan Zheng struct btrfs_key key; 17105d4f98a2SYan Zheng u64 old_bytenr; 17115d4f98a2SYan Zheng u64 new_bytenr; 17125d4f98a2SYan Zheng u64 old_ptr_gen; 17135d4f98a2SYan Zheng u64 new_ptr_gen; 17145d4f98a2SYan Zheng u64 last_snapshot; 17155d4f98a2SYan Zheng u32 blocksize; 17163fd0a558SYan, Zheng int cow = 0; 17175d4f98a2SYan Zheng int level; 17185d4f98a2SYan Zheng int ret; 17195d4f98a2SYan Zheng int slot; 17205d4f98a2SYan Zheng 17215d4f98a2SYan Zheng BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 17225d4f98a2SYan Zheng BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); 17235d4f98a2SYan Zheng 17245d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&src->root_item); 17253fd0a558SYan, Zheng again: 17265d4f98a2SYan Zheng slot = path->slots[lowest_level]; 17275d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); 17285d4f98a2SYan Zheng 17295d4f98a2SYan Zheng eb = btrfs_lock_root_node(dest); 17308bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 17315d4f98a2SYan Zheng level = btrfs_header_level(eb); 17325d4f98a2SYan Zheng 17335d4f98a2SYan Zheng if (level < lowest_level) { 17345d4f98a2SYan Zheng btrfs_tree_unlock(eb); 17355d4f98a2SYan Zheng free_extent_buffer(eb); 17365d4f98a2SYan Zheng return 0; 17375d4f98a2SYan Zheng } 17385d4f98a2SYan Zheng 17393fd0a558SYan, Zheng if (cow) { 17405d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); 17415d4f98a2SYan Zheng BUG_ON(ret); 17423fd0a558SYan, Zheng } 17438bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 17445d4f98a2SYan Zheng 17455d4f98a2SYan Zheng if (next_key) { 17465d4f98a2SYan Zheng next_key->objectid = (u64)-1; 17475d4f98a2SYan Zheng next_key->type = (u8)-1; 17485d4f98a2SYan Zheng next_key->offset = (u64)-1; 17495d4f98a2SYan Zheng } 17505d4f98a2SYan Zheng 17515d4f98a2SYan Zheng parent = eb; 17525d4f98a2SYan Zheng while (1) { 1753581c1760SQu Wenruo struct btrfs_key first_key; 1754581c1760SQu Wenruo 17555d4f98a2SYan Zheng level = btrfs_header_level(parent); 17565d4f98a2SYan Zheng BUG_ON(level < lowest_level); 17575d4f98a2SYan Zheng 17585d4f98a2SYan Zheng ret = btrfs_bin_search(parent, &key, level, &slot); 1759cbca7d59SFilipe Manana if (ret < 0) 1760cbca7d59SFilipe Manana break; 17615d4f98a2SYan Zheng if (ret && slot > 0) 17625d4f98a2SYan Zheng slot--; 17635d4f98a2SYan Zheng 17645d4f98a2SYan Zheng if (next_key && slot + 1 < btrfs_header_nritems(parent)) 17655d4f98a2SYan Zheng btrfs_node_key_to_cpu(parent, next_key, slot + 1); 17665d4f98a2SYan Zheng 17675d4f98a2SYan Zheng old_bytenr = btrfs_node_blockptr(parent, slot); 17680b246afaSJeff Mahoney blocksize = fs_info->nodesize; 17695d4f98a2SYan Zheng old_ptr_gen = btrfs_node_ptr_generation(parent, slot); 177017515f1bSQu Wenruo btrfs_node_key_to_cpu(parent, &first_key, slot); 17715d4f98a2SYan Zheng 17725d4f98a2SYan Zheng if (level <= max_level) { 17735d4f98a2SYan Zheng eb = path->nodes[level]; 17745d4f98a2SYan Zheng new_bytenr = btrfs_node_blockptr(eb, 17755d4f98a2SYan Zheng path->slots[level]); 17765d4f98a2SYan Zheng new_ptr_gen = btrfs_node_ptr_generation(eb, 17775d4f98a2SYan Zheng path->slots[level]); 17785d4f98a2SYan Zheng } else { 17795d4f98a2SYan Zheng new_bytenr = 0; 17805d4f98a2SYan Zheng new_ptr_gen = 0; 17815d4f98a2SYan Zheng } 17825d4f98a2SYan Zheng 1783fae7f21cSDulshani Gunawardhana if (WARN_ON(new_bytenr > 0 && new_bytenr == old_bytenr)) { 17845d4f98a2SYan Zheng ret = level; 17855d4f98a2SYan Zheng break; 17865d4f98a2SYan Zheng } 17875d4f98a2SYan Zheng 17885d4f98a2SYan Zheng if (new_bytenr == 0 || old_ptr_gen > last_snapshot || 17895d4f98a2SYan Zheng memcmp_node_keys(parent, slot, path, level)) { 17903fd0a558SYan, Zheng if (level <= lowest_level) { 17915d4f98a2SYan Zheng ret = 0; 17925d4f98a2SYan Zheng break; 17935d4f98a2SYan Zheng } 17945d4f98a2SYan Zheng 1795581c1760SQu Wenruo eb = read_tree_block(fs_info, old_bytenr, old_ptr_gen, 1796581c1760SQu Wenruo level - 1, &first_key); 179764c043deSLiu Bo if (IS_ERR(eb)) { 179864c043deSLiu Bo ret = PTR_ERR(eb); 1799264813acSLiu Bo break; 180064c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 180164c043deSLiu Bo ret = -EIO; 1802416bc658SJosef Bacik free_extent_buffer(eb); 1803379cde74SStefan Behrens break; 1804416bc658SJosef Bacik } 18055d4f98a2SYan Zheng btrfs_tree_lock(eb); 18063fd0a558SYan, Zheng if (cow) { 18075d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, parent, 18085d4f98a2SYan Zheng slot, &eb); 18095d4f98a2SYan Zheng BUG_ON(ret); 18105d4f98a2SYan Zheng } 18118bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 18125d4f98a2SYan Zheng 18135d4f98a2SYan Zheng btrfs_tree_unlock(parent); 18145d4f98a2SYan Zheng free_extent_buffer(parent); 18155d4f98a2SYan Zheng 18165d4f98a2SYan Zheng parent = eb; 18175d4f98a2SYan Zheng continue; 18185d4f98a2SYan Zheng } 18195d4f98a2SYan Zheng 18203fd0a558SYan, Zheng if (!cow) { 18213fd0a558SYan, Zheng btrfs_tree_unlock(parent); 18223fd0a558SYan, Zheng free_extent_buffer(parent); 18233fd0a558SYan, Zheng cow = 1; 18243fd0a558SYan, Zheng goto again; 18253fd0a558SYan, Zheng } 18263fd0a558SYan, Zheng 18275d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 18285d4f98a2SYan Zheng path->slots[level]); 1829b3b4aa74SDavid Sterba btrfs_release_path(path); 18305d4f98a2SYan Zheng 18315d4f98a2SYan Zheng path->lowest_level = level; 18325d4f98a2SYan Zheng ret = btrfs_search_slot(trans, src, &key, path, 0, 1); 18335d4f98a2SYan Zheng path->lowest_level = 0; 18345d4f98a2SYan Zheng BUG_ON(ret); 18355d4f98a2SYan Zheng 18365d4f98a2SYan Zheng /* 1837824d8dffSQu Wenruo * Info qgroup to trace both subtrees. 1838824d8dffSQu Wenruo * 1839824d8dffSQu Wenruo * We must trace both trees. 1840824d8dffSQu Wenruo * 1) Tree reloc subtree 1841824d8dffSQu Wenruo * If not traced, we will leak data numbers 1842824d8dffSQu Wenruo * 2) Fs subtree 1843824d8dffSQu Wenruo * If not traced, we will double count old data 1844f616f5cdSQu Wenruo * 1845f616f5cdSQu Wenruo * We don't scan the subtree right now, but only record 1846f616f5cdSQu Wenruo * the swapped tree blocks. 1847f616f5cdSQu Wenruo * The real subtree rescan is delayed until we have new 1848f616f5cdSQu Wenruo * CoW on the subtree root node before transaction commit. 1849824d8dffSQu Wenruo */ 1850370a11b8SQu Wenruo ret = btrfs_qgroup_add_swapped_blocks(trans, dest, 1851370a11b8SQu Wenruo rc->block_group, parent, slot, 1852370a11b8SQu Wenruo path->nodes[level], path->slots[level], 1853370a11b8SQu Wenruo last_snapshot); 1854370a11b8SQu Wenruo if (ret < 0) 1855370a11b8SQu Wenruo break; 1856824d8dffSQu Wenruo /* 18575d4f98a2SYan Zheng * swap blocks in fs tree and reloc tree. 18585d4f98a2SYan Zheng */ 18595d4f98a2SYan Zheng btrfs_set_node_blockptr(parent, slot, new_bytenr); 18605d4f98a2SYan Zheng btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); 18615d4f98a2SYan Zheng btrfs_mark_buffer_dirty(parent); 18625d4f98a2SYan Zheng 18635d4f98a2SYan Zheng btrfs_set_node_blockptr(path->nodes[level], 18645d4f98a2SYan Zheng path->slots[level], old_bytenr); 18655d4f98a2SYan Zheng btrfs_set_node_ptr_generation(path->nodes[level], 18665d4f98a2SYan Zheng path->slots[level], old_ptr_gen); 18675d4f98a2SYan Zheng btrfs_mark_buffer_dirty(path->nodes[level]); 18685d4f98a2SYan Zheng 186982fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, old_bytenr, 187082fa113fSQu Wenruo blocksize, path->nodes[level]->start); 187182fa113fSQu Wenruo ref.skip_qgroup = true; 187282fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 187382fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 18745d4f98a2SYan Zheng BUG_ON(ret); 187582fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 187682fa113fSQu Wenruo blocksize, 0); 187782fa113fSQu Wenruo ref.skip_qgroup = true; 187882fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 187982fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 18805d4f98a2SYan Zheng BUG_ON(ret); 18815d4f98a2SYan Zheng 1882ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, new_bytenr, 1883ffd4bb2aSQu Wenruo blocksize, path->nodes[level]->start); 1884ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 1885ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 1886ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 18875d4f98a2SYan Zheng BUG_ON(ret); 18885d4f98a2SYan Zheng 1889ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, old_bytenr, 1890ffd4bb2aSQu Wenruo blocksize, 0); 1891ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 1892ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 1893ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 18945d4f98a2SYan Zheng BUG_ON(ret); 18955d4f98a2SYan Zheng 18965d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 18975d4f98a2SYan Zheng 18985d4f98a2SYan Zheng ret = level; 18995d4f98a2SYan Zheng break; 19005d4f98a2SYan Zheng } 19015d4f98a2SYan Zheng btrfs_tree_unlock(parent); 19025d4f98a2SYan Zheng free_extent_buffer(parent); 19035d4f98a2SYan Zheng return ret; 19045d4f98a2SYan Zheng } 19055d4f98a2SYan Zheng 19065d4f98a2SYan Zheng /* 19075d4f98a2SYan Zheng * helper to find next relocated block in reloc tree 19085d4f98a2SYan Zheng */ 19095d4f98a2SYan Zheng static noinline_for_stack 19105d4f98a2SYan Zheng int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 19115d4f98a2SYan Zheng int *level) 19125d4f98a2SYan Zheng { 19135d4f98a2SYan Zheng struct extent_buffer *eb; 19145d4f98a2SYan Zheng int i; 19155d4f98a2SYan Zheng u64 last_snapshot; 19165d4f98a2SYan Zheng u32 nritems; 19175d4f98a2SYan Zheng 19185d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 19195d4f98a2SYan Zheng 19205d4f98a2SYan Zheng for (i = 0; i < *level; i++) { 19215d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 19225d4f98a2SYan Zheng path->nodes[i] = NULL; 19235d4f98a2SYan Zheng } 19245d4f98a2SYan Zheng 19255d4f98a2SYan Zheng for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { 19265d4f98a2SYan Zheng eb = path->nodes[i]; 19275d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 19285d4f98a2SYan Zheng while (path->slots[i] + 1 < nritems) { 19295d4f98a2SYan Zheng path->slots[i]++; 19305d4f98a2SYan Zheng if (btrfs_node_ptr_generation(eb, path->slots[i]) <= 19315d4f98a2SYan Zheng last_snapshot) 19325d4f98a2SYan Zheng continue; 19335d4f98a2SYan Zheng 19345d4f98a2SYan Zheng *level = i; 19355d4f98a2SYan Zheng return 0; 19365d4f98a2SYan Zheng } 19375d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 19385d4f98a2SYan Zheng path->nodes[i] = NULL; 19395d4f98a2SYan Zheng } 19405d4f98a2SYan Zheng return 1; 19415d4f98a2SYan Zheng } 19425d4f98a2SYan Zheng 19435d4f98a2SYan Zheng /* 19445d4f98a2SYan Zheng * walk down reloc tree to find relocated block of lowest level 19455d4f98a2SYan Zheng */ 19465d4f98a2SYan Zheng static noinline_for_stack 19475d4f98a2SYan Zheng int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 19485d4f98a2SYan Zheng int *level) 19495d4f98a2SYan Zheng { 19502ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 19515d4f98a2SYan Zheng struct extent_buffer *eb = NULL; 19525d4f98a2SYan Zheng int i; 19535d4f98a2SYan Zheng u64 bytenr; 19545d4f98a2SYan Zheng u64 ptr_gen = 0; 19555d4f98a2SYan Zheng u64 last_snapshot; 19565d4f98a2SYan Zheng u32 nritems; 19575d4f98a2SYan Zheng 19585d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 19595d4f98a2SYan Zheng 19605d4f98a2SYan Zheng for (i = *level; i > 0; i--) { 1961581c1760SQu Wenruo struct btrfs_key first_key; 1962581c1760SQu Wenruo 19635d4f98a2SYan Zheng eb = path->nodes[i]; 19645d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 19655d4f98a2SYan Zheng while (path->slots[i] < nritems) { 19665d4f98a2SYan Zheng ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); 19675d4f98a2SYan Zheng if (ptr_gen > last_snapshot) 19685d4f98a2SYan Zheng break; 19695d4f98a2SYan Zheng path->slots[i]++; 19705d4f98a2SYan Zheng } 19715d4f98a2SYan Zheng if (path->slots[i] >= nritems) { 19725d4f98a2SYan Zheng if (i == *level) 19735d4f98a2SYan Zheng break; 19745d4f98a2SYan Zheng *level = i + 1; 19755d4f98a2SYan Zheng return 0; 19765d4f98a2SYan Zheng } 19775d4f98a2SYan Zheng if (i == 1) { 19785d4f98a2SYan Zheng *level = i; 19795d4f98a2SYan Zheng return 0; 19805d4f98a2SYan Zheng } 19815d4f98a2SYan Zheng 19825d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(eb, path->slots[i]); 1983581c1760SQu Wenruo btrfs_node_key_to_cpu(eb, &first_key, path->slots[i]); 1984581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, ptr_gen, i - 1, 1985581c1760SQu Wenruo &first_key); 198664c043deSLiu Bo if (IS_ERR(eb)) { 198764c043deSLiu Bo return PTR_ERR(eb); 198864c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 1989416bc658SJosef Bacik free_extent_buffer(eb); 1990416bc658SJosef Bacik return -EIO; 1991416bc658SJosef Bacik } 19925d4f98a2SYan Zheng BUG_ON(btrfs_header_level(eb) != i - 1); 19935d4f98a2SYan Zheng path->nodes[i - 1] = eb; 19945d4f98a2SYan Zheng path->slots[i - 1] = 0; 19955d4f98a2SYan Zheng } 19965d4f98a2SYan Zheng return 1; 19975d4f98a2SYan Zheng } 19985d4f98a2SYan Zheng 19995d4f98a2SYan Zheng /* 20005d4f98a2SYan Zheng * invalidate extent cache for file extents whose key in range of 20015d4f98a2SYan Zheng * [min_key, max_key) 20025d4f98a2SYan Zheng */ 20035d4f98a2SYan Zheng static int invalidate_extent_cache(struct btrfs_root *root, 20045d4f98a2SYan Zheng struct btrfs_key *min_key, 20055d4f98a2SYan Zheng struct btrfs_key *max_key) 20065d4f98a2SYan Zheng { 20070b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 20085d4f98a2SYan Zheng struct inode *inode = NULL; 20095d4f98a2SYan Zheng u64 objectid; 20105d4f98a2SYan Zheng u64 start, end; 201133345d01SLi Zefan u64 ino; 20125d4f98a2SYan Zheng 20135d4f98a2SYan Zheng objectid = min_key->objectid; 20145d4f98a2SYan Zheng while (1) { 20155d4f98a2SYan Zheng cond_resched(); 20165d4f98a2SYan Zheng iput(inode); 20175d4f98a2SYan Zheng 20185d4f98a2SYan Zheng if (objectid > max_key->objectid) 20195d4f98a2SYan Zheng break; 20205d4f98a2SYan Zheng 20215d4f98a2SYan Zheng inode = find_next_inode(root, objectid); 20225d4f98a2SYan Zheng if (!inode) 20235d4f98a2SYan Zheng break; 20244a0cc7caSNikolay Borisov ino = btrfs_ino(BTRFS_I(inode)); 20255d4f98a2SYan Zheng 202633345d01SLi Zefan if (ino > max_key->objectid) { 20275d4f98a2SYan Zheng iput(inode); 20285d4f98a2SYan Zheng break; 20295d4f98a2SYan Zheng } 20305d4f98a2SYan Zheng 203133345d01SLi Zefan objectid = ino + 1; 20325d4f98a2SYan Zheng if (!S_ISREG(inode->i_mode)) 20335d4f98a2SYan Zheng continue; 20345d4f98a2SYan Zheng 203533345d01SLi Zefan if (unlikely(min_key->objectid == ino)) { 20365d4f98a2SYan Zheng if (min_key->type > BTRFS_EXTENT_DATA_KEY) 20375d4f98a2SYan Zheng continue; 20385d4f98a2SYan Zheng if (min_key->type < BTRFS_EXTENT_DATA_KEY) 20395d4f98a2SYan Zheng start = 0; 20405d4f98a2SYan Zheng else { 20415d4f98a2SYan Zheng start = min_key->offset; 20420b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(start, fs_info->sectorsize)); 20435d4f98a2SYan Zheng } 20445d4f98a2SYan Zheng } else { 20455d4f98a2SYan Zheng start = 0; 20465d4f98a2SYan Zheng } 20475d4f98a2SYan Zheng 204833345d01SLi Zefan if (unlikely(max_key->objectid == ino)) { 20495d4f98a2SYan Zheng if (max_key->type < BTRFS_EXTENT_DATA_KEY) 20505d4f98a2SYan Zheng continue; 20515d4f98a2SYan Zheng if (max_key->type > BTRFS_EXTENT_DATA_KEY) { 20525d4f98a2SYan Zheng end = (u64)-1; 20535d4f98a2SYan Zheng } else { 20545d4f98a2SYan Zheng if (max_key->offset == 0) 20555d4f98a2SYan Zheng continue; 20565d4f98a2SYan Zheng end = max_key->offset; 20570b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 20585d4f98a2SYan Zheng end--; 20595d4f98a2SYan Zheng } 20605d4f98a2SYan Zheng } else { 20615d4f98a2SYan Zheng end = (u64)-1; 20625d4f98a2SYan Zheng } 20635d4f98a2SYan Zheng 20645d4f98a2SYan Zheng /* the lock_extent waits for readpage to complete */ 2065d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 2066dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 1); 2067d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 20685d4f98a2SYan Zheng } 20695d4f98a2SYan Zheng return 0; 20705d4f98a2SYan Zheng } 20715d4f98a2SYan Zheng 20725d4f98a2SYan Zheng static int find_next_key(struct btrfs_path *path, int level, 20735d4f98a2SYan Zheng struct btrfs_key *key) 20745d4f98a2SYan Zheng 20755d4f98a2SYan Zheng { 20765d4f98a2SYan Zheng while (level < BTRFS_MAX_LEVEL) { 20775d4f98a2SYan Zheng if (!path->nodes[level]) 20785d4f98a2SYan Zheng break; 20795d4f98a2SYan Zheng if (path->slots[level] + 1 < 20805d4f98a2SYan Zheng btrfs_header_nritems(path->nodes[level])) { 20815d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], key, 20825d4f98a2SYan Zheng path->slots[level] + 1); 20835d4f98a2SYan Zheng return 0; 20845d4f98a2SYan Zheng } 20855d4f98a2SYan Zheng level++; 20865d4f98a2SYan Zheng } 20875d4f98a2SYan Zheng return 1; 20885d4f98a2SYan Zheng } 20895d4f98a2SYan Zheng 20905d4f98a2SYan Zheng /* 2091d2311e69SQu Wenruo * Insert current subvolume into reloc_control::dirty_subvol_roots 2092d2311e69SQu Wenruo */ 2093d2311e69SQu Wenruo static void insert_dirty_subvol(struct btrfs_trans_handle *trans, 2094d2311e69SQu Wenruo struct reloc_control *rc, 2095d2311e69SQu Wenruo struct btrfs_root *root) 2096d2311e69SQu Wenruo { 2097d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2098d2311e69SQu Wenruo struct btrfs_root_item *reloc_root_item; 2099d2311e69SQu Wenruo 2100d2311e69SQu Wenruo /* @root must be a subvolume tree root with a valid reloc tree */ 2101d2311e69SQu Wenruo ASSERT(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 2102d2311e69SQu Wenruo ASSERT(reloc_root); 2103d2311e69SQu Wenruo 2104d2311e69SQu Wenruo reloc_root_item = &reloc_root->root_item; 2105d2311e69SQu Wenruo memset(&reloc_root_item->drop_progress, 0, 2106d2311e69SQu Wenruo sizeof(reloc_root_item->drop_progress)); 2107d2311e69SQu Wenruo reloc_root_item->drop_level = 0; 2108d2311e69SQu Wenruo btrfs_set_root_refs(reloc_root_item, 0); 2109d2311e69SQu Wenruo btrfs_update_reloc_root(trans, root); 2110d2311e69SQu Wenruo 2111d2311e69SQu Wenruo if (list_empty(&root->reloc_dirty_list)) { 211200246528SJosef Bacik btrfs_grab_root(root); 2113d2311e69SQu Wenruo list_add_tail(&root->reloc_dirty_list, &rc->dirty_subvol_roots); 2114d2311e69SQu Wenruo } 2115d2311e69SQu Wenruo } 2116d2311e69SQu Wenruo 2117d2311e69SQu Wenruo static int clean_dirty_subvols(struct reloc_control *rc) 2118d2311e69SQu Wenruo { 2119d2311e69SQu Wenruo struct btrfs_root *root; 2120d2311e69SQu Wenruo struct btrfs_root *next; 2121d2311e69SQu Wenruo int ret = 0; 212230d40577SQu Wenruo int ret2; 2123d2311e69SQu Wenruo 2124d2311e69SQu Wenruo list_for_each_entry_safe(root, next, &rc->dirty_subvol_roots, 2125d2311e69SQu Wenruo reloc_dirty_list) { 212630d40577SQu Wenruo if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 212730d40577SQu Wenruo /* Merged subvolume, cleanup its reloc root */ 2128d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2129d2311e69SQu Wenruo 2130d2311e69SQu Wenruo list_del_init(&root->reloc_dirty_list); 2131d2311e69SQu Wenruo root->reloc_root = NULL; 21326282675eSQu Wenruo /* 21336282675eSQu Wenruo * Need barrier to ensure clear_bit() only happens after 21346282675eSQu Wenruo * root->reloc_root = NULL. Pairs with have_reloc_root. 21356282675eSQu Wenruo */ 21366282675eSQu Wenruo smp_wmb(); 21371fac4a54SQu Wenruo clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 2138f28de8d8SJosef Bacik if (reloc_root) { 2139f44deb74SJosef Bacik /* 2140f44deb74SJosef Bacik * btrfs_drop_snapshot drops our ref we hold for 2141f44deb74SJosef Bacik * ->reloc_root. If it fails however we must 2142f44deb74SJosef Bacik * drop the ref ourselves. 2143f44deb74SJosef Bacik */ 2144f28de8d8SJosef Bacik ret2 = btrfs_drop_snapshot(reloc_root, 0, 1); 2145f44deb74SJosef Bacik if (ret2 < 0) { 2146f44deb74SJosef Bacik btrfs_put_root(reloc_root); 2147f44deb74SJosef Bacik if (!ret) 2148f28de8d8SJosef Bacik ret = ret2; 2149f28de8d8SJosef Bacik } 2150f44deb74SJosef Bacik } 215100246528SJosef Bacik btrfs_put_root(root); 215230d40577SQu Wenruo } else { 215330d40577SQu Wenruo /* Orphan reloc tree, just clean it up */ 21540078a9f9SNikolay Borisov ret2 = btrfs_drop_snapshot(root, 0, 1); 2155f44deb74SJosef Bacik if (ret2 < 0) { 2156f44deb74SJosef Bacik btrfs_put_root(root); 2157f44deb74SJosef Bacik if (!ret) 215830d40577SQu Wenruo ret = ret2; 215930d40577SQu Wenruo } 2160d2311e69SQu Wenruo } 2161f44deb74SJosef Bacik } 2162d2311e69SQu Wenruo return ret; 2163d2311e69SQu Wenruo } 2164d2311e69SQu Wenruo 2165d2311e69SQu Wenruo /* 21665d4f98a2SYan Zheng * merge the relocated tree blocks in reloc tree with corresponding 21675d4f98a2SYan Zheng * fs tree. 21685d4f98a2SYan Zheng */ 21695d4f98a2SYan Zheng static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, 21705d4f98a2SYan Zheng struct btrfs_root *root) 21715d4f98a2SYan Zheng { 21720b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 21735d4f98a2SYan Zheng struct btrfs_key key; 21745d4f98a2SYan Zheng struct btrfs_key next_key; 21759e6a0c52SJosef Bacik struct btrfs_trans_handle *trans = NULL; 21765d4f98a2SYan Zheng struct btrfs_root *reloc_root; 21775d4f98a2SYan Zheng struct btrfs_root_item *root_item; 21785d4f98a2SYan Zheng struct btrfs_path *path; 21793fd0a558SYan, Zheng struct extent_buffer *leaf; 21805d4f98a2SYan Zheng int level; 21815d4f98a2SYan Zheng int max_level; 21825d4f98a2SYan Zheng int replaced = 0; 21835d4f98a2SYan Zheng int ret; 21845d4f98a2SYan Zheng int err = 0; 21853fd0a558SYan, Zheng u32 min_reserved; 21865d4f98a2SYan Zheng 21875d4f98a2SYan Zheng path = btrfs_alloc_path(); 21885d4f98a2SYan Zheng if (!path) 21895d4f98a2SYan Zheng return -ENOMEM; 2190e4058b54SDavid Sterba path->reada = READA_FORWARD; 21915d4f98a2SYan Zheng 21925d4f98a2SYan Zheng reloc_root = root->reloc_root; 21935d4f98a2SYan Zheng root_item = &reloc_root->root_item; 21945d4f98a2SYan Zheng 21955d4f98a2SYan Zheng if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { 21965d4f98a2SYan Zheng level = btrfs_root_level(root_item); 219767439dadSDavid Sterba atomic_inc(&reloc_root->node->refs); 21985d4f98a2SYan Zheng path->nodes[level] = reloc_root->node; 21995d4f98a2SYan Zheng path->slots[level] = 0; 22005d4f98a2SYan Zheng } else { 22015d4f98a2SYan Zheng btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); 22025d4f98a2SYan Zheng 22035d4f98a2SYan Zheng level = root_item->drop_level; 22045d4f98a2SYan Zheng BUG_ON(level == 0); 22055d4f98a2SYan Zheng path->lowest_level = level; 22065d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); 220733c66f43SYan Zheng path->lowest_level = 0; 22085d4f98a2SYan Zheng if (ret < 0) { 22095d4f98a2SYan Zheng btrfs_free_path(path); 22105d4f98a2SYan Zheng return ret; 22115d4f98a2SYan Zheng } 22125d4f98a2SYan Zheng 22135d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &next_key, 22145d4f98a2SYan Zheng path->slots[level]); 22155d4f98a2SYan Zheng WARN_ON(memcmp(&key, &next_key, sizeof(key))); 22165d4f98a2SYan Zheng 22175d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 22185d4f98a2SYan Zheng } 22195d4f98a2SYan Zheng 22200b246afaSJeff Mahoney min_reserved = fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 22215d4f98a2SYan Zheng memset(&next_key, 0, sizeof(next_key)); 22225d4f98a2SYan Zheng 22235d4f98a2SYan Zheng while (1) { 222408e007d2SMiao Xie ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved, 222508e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 22263fd0a558SYan, Zheng if (ret) { 22279e6a0c52SJosef Bacik err = ret; 22289e6a0c52SJosef Bacik goto out; 22293fd0a558SYan, Zheng } 22309e6a0c52SJosef Bacik trans = btrfs_start_transaction(root, 0); 22319e6a0c52SJosef Bacik if (IS_ERR(trans)) { 22329e6a0c52SJosef Bacik err = PTR_ERR(trans); 22339e6a0c52SJosef Bacik trans = NULL; 22349e6a0c52SJosef Bacik goto out; 22359e6a0c52SJosef Bacik } 22362abc726aSJosef Bacik 22372abc726aSJosef Bacik /* 22382abc726aSJosef Bacik * At this point we no longer have a reloc_control, so we can't 22392abc726aSJosef Bacik * depend on btrfs_init_reloc_root to update our last_trans. 22402abc726aSJosef Bacik * 22412abc726aSJosef Bacik * But that's ok, we started the trans handle on our 22422abc726aSJosef Bacik * corresponding fs_root, which means it's been added to the 22432abc726aSJosef Bacik * dirty list. At commit time we'll still call 22442abc726aSJosef Bacik * btrfs_update_reloc_root() and update our root item 22452abc726aSJosef Bacik * appropriately. 22462abc726aSJosef Bacik */ 22472abc726aSJosef Bacik reloc_root->last_trans = trans->transid; 22489e6a0c52SJosef Bacik trans->block_rsv = rc->block_rsv; 22493fd0a558SYan, Zheng 22503fd0a558SYan, Zheng replaced = 0; 22515d4f98a2SYan Zheng max_level = level; 22525d4f98a2SYan Zheng 22535d4f98a2SYan Zheng ret = walk_down_reloc_tree(reloc_root, path, &level); 22545d4f98a2SYan Zheng if (ret < 0) { 22555d4f98a2SYan Zheng err = ret; 22565d4f98a2SYan Zheng goto out; 22575d4f98a2SYan Zheng } 22585d4f98a2SYan Zheng if (ret > 0) 22595d4f98a2SYan Zheng break; 22605d4f98a2SYan Zheng 22615d4f98a2SYan Zheng if (!find_next_key(path, level, &key) && 22625d4f98a2SYan Zheng btrfs_comp_cpu_keys(&next_key, &key) >= 0) { 22635d4f98a2SYan Zheng ret = 0; 22645d4f98a2SYan Zheng } else { 22653d0174f7SQu Wenruo ret = replace_path(trans, rc, root, reloc_root, path, 22663fd0a558SYan, Zheng &next_key, level, max_level); 22675d4f98a2SYan Zheng } 22685d4f98a2SYan Zheng if (ret < 0) { 22695d4f98a2SYan Zheng err = ret; 22705d4f98a2SYan Zheng goto out; 22715d4f98a2SYan Zheng } 22725d4f98a2SYan Zheng 22735d4f98a2SYan Zheng if (ret > 0) { 22745d4f98a2SYan Zheng level = ret; 22755d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 22765d4f98a2SYan Zheng path->slots[level]); 22775d4f98a2SYan Zheng replaced = 1; 22785d4f98a2SYan Zheng } 22795d4f98a2SYan Zheng 22805d4f98a2SYan Zheng ret = walk_up_reloc_tree(reloc_root, path, &level); 22815d4f98a2SYan Zheng if (ret > 0) 22825d4f98a2SYan Zheng break; 22835d4f98a2SYan Zheng 22845d4f98a2SYan Zheng BUG_ON(level == 0); 22855d4f98a2SYan Zheng /* 22865d4f98a2SYan Zheng * save the merging progress in the drop_progress. 22875d4f98a2SYan Zheng * this is OK since root refs == 1 in this case. 22885d4f98a2SYan Zheng */ 22895d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &root_item->drop_progress, 22905d4f98a2SYan Zheng path->slots[level]); 22915d4f98a2SYan Zheng root_item->drop_level = level; 22925d4f98a2SYan Zheng 22933a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 22949e6a0c52SJosef Bacik trans = NULL; 22955d4f98a2SYan Zheng 22962ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 22975d4f98a2SYan Zheng 22985d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 22995d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 23005d4f98a2SYan Zheng } 23015d4f98a2SYan Zheng 23025d4f98a2SYan Zheng /* 23035d4f98a2SYan Zheng * handle the case only one block in the fs tree need to be 23045d4f98a2SYan Zheng * relocated and the block is tree root. 23055d4f98a2SYan Zheng */ 23065d4f98a2SYan Zheng leaf = btrfs_lock_root_node(root); 23075d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); 23085d4f98a2SYan Zheng btrfs_tree_unlock(leaf); 23095d4f98a2SYan Zheng free_extent_buffer(leaf); 23105d4f98a2SYan Zheng if (ret < 0) 23115d4f98a2SYan Zheng err = ret; 23125d4f98a2SYan Zheng out: 23135d4f98a2SYan Zheng btrfs_free_path(path); 23145d4f98a2SYan Zheng 2315d2311e69SQu Wenruo if (err == 0) 2316d2311e69SQu Wenruo insert_dirty_subvol(trans, rc, root); 23175d4f98a2SYan Zheng 23189e6a0c52SJosef Bacik if (trans) 23193a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 23205d4f98a2SYan Zheng 23212ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 23225d4f98a2SYan Zheng 23235d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 23245d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 23255d4f98a2SYan Zheng 23265d4f98a2SYan Zheng return err; 23275d4f98a2SYan Zheng } 23285d4f98a2SYan Zheng 23293fd0a558SYan, Zheng static noinline_for_stack 23303fd0a558SYan, Zheng int prepare_to_merge(struct reloc_control *rc, int err) 23315d4f98a2SYan Zheng { 23323fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 23330b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 23343fd0a558SYan, Zheng struct btrfs_root *reloc_root; 23355d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 23363fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 23373fd0a558SYan, Zheng u64 num_bytes = 0; 23383fd0a558SYan, Zheng int ret; 23393fd0a558SYan, Zheng 23400b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 23410b246afaSJeff Mahoney rc->merging_rsv_size += fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 23423fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated * 2; 23430b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 23447585717fSChris Mason 23453fd0a558SYan, Zheng again: 23463fd0a558SYan, Zheng if (!err) { 23473fd0a558SYan, Zheng num_bytes = rc->merging_rsv_size; 234808e007d2SMiao Xie ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes, 234908e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 23503fd0a558SYan, Zheng if (ret) 23513fd0a558SYan, Zheng err = ret; 23523fd0a558SYan, Zheng } 23533fd0a558SYan, Zheng 23547a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 23553612b495STsutomu Itoh if (IS_ERR(trans)) { 23563612b495STsutomu Itoh if (!err) 23572ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 235863f018beSNikolay Borisov num_bytes, NULL); 23593612b495STsutomu Itoh return PTR_ERR(trans); 23603612b495STsutomu Itoh } 23613fd0a558SYan, Zheng 23623fd0a558SYan, Zheng if (!err) { 23633fd0a558SYan, Zheng if (num_bytes != rc->merging_rsv_size) { 23643a45bb20SJeff Mahoney btrfs_end_transaction(trans); 23652ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 236663f018beSNikolay Borisov num_bytes, NULL); 23673fd0a558SYan, Zheng goto again; 23683fd0a558SYan, Zheng } 23693fd0a558SYan, Zheng } 23703fd0a558SYan, Zheng 23713fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 23723fd0a558SYan, Zheng 23733fd0a558SYan, Zheng while (!list_empty(&rc->reloc_roots)) { 23743fd0a558SYan, Zheng reloc_root = list_entry(rc->reloc_roots.next, 23753fd0a558SYan, Zheng struct btrfs_root, root_list); 23763fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 23773fd0a558SYan, Zheng 23780b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 23793fd0a558SYan, Zheng BUG_ON(IS_ERR(root)); 23803fd0a558SYan, Zheng BUG_ON(root->reloc_root != reloc_root); 23813fd0a558SYan, Zheng 23823fd0a558SYan, Zheng /* 23833fd0a558SYan, Zheng * set reference count to 1, so btrfs_recover_relocation 23843fd0a558SYan, Zheng * knows it should resumes merging 23853fd0a558SYan, Zheng */ 23863fd0a558SYan, Zheng if (!err) 23873fd0a558SYan, Zheng btrfs_set_root_refs(&reloc_root->root_item, 1); 23883fd0a558SYan, Zheng btrfs_update_reloc_root(trans, root); 23893fd0a558SYan, Zheng 23903fd0a558SYan, Zheng list_add(&reloc_root->root_list, &reloc_roots); 239100246528SJosef Bacik btrfs_put_root(root); 23923fd0a558SYan, Zheng } 23933fd0a558SYan, Zheng 23943fd0a558SYan, Zheng list_splice(&reloc_roots, &rc->reloc_roots); 23953fd0a558SYan, Zheng 23963fd0a558SYan, Zheng if (!err) 23973a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 23983fd0a558SYan, Zheng else 23993a45bb20SJeff Mahoney btrfs_end_transaction(trans); 24003fd0a558SYan, Zheng return err; 24013fd0a558SYan, Zheng } 24023fd0a558SYan, Zheng 24033fd0a558SYan, Zheng static noinline_for_stack 2404aca1bba6SLiu Bo void free_reloc_roots(struct list_head *list) 2405aca1bba6SLiu Bo { 2406aca1bba6SLiu Bo struct btrfs_root *reloc_root; 2407aca1bba6SLiu Bo 2408aca1bba6SLiu Bo while (!list_empty(list)) { 2409aca1bba6SLiu Bo reloc_root = list_entry(list->next, struct btrfs_root, 2410aca1bba6SLiu Bo root_list); 2411bb166d72SNaohiro Aota __del_reloc_root(reloc_root); 2412aca1bba6SLiu Bo } 2413aca1bba6SLiu Bo } 2414aca1bba6SLiu Bo 2415aca1bba6SLiu Bo static noinline_for_stack 241694404e82SDavid Sterba void merge_reloc_roots(struct reloc_control *rc) 24173fd0a558SYan, Zheng { 24180b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 24195d4f98a2SYan Zheng struct btrfs_root *root; 24205d4f98a2SYan Zheng struct btrfs_root *reloc_root; 24213fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 24223fd0a558SYan, Zheng int found = 0; 2423aca1bba6SLiu Bo int ret = 0; 24243fd0a558SYan, Zheng again: 24253fd0a558SYan, Zheng root = rc->extent_root; 24267585717fSChris Mason 24277585717fSChris Mason /* 24287585717fSChris Mason * this serializes us with btrfs_record_root_in_transaction, 24297585717fSChris Mason * we have to make sure nobody is in the middle of 24307585717fSChris Mason * adding their roots to the list while we are 24317585717fSChris Mason * doing this splice 24327585717fSChris Mason */ 24330b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 24343fd0a558SYan, Zheng list_splice_init(&rc->reloc_roots, &reloc_roots); 24350b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 24365d4f98a2SYan Zheng 24373fd0a558SYan, Zheng while (!list_empty(&reloc_roots)) { 24383fd0a558SYan, Zheng found = 1; 24393fd0a558SYan, Zheng reloc_root = list_entry(reloc_roots.next, 24403fd0a558SYan, Zheng struct btrfs_root, root_list); 24415d4f98a2SYan Zheng 24425d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 24430b246afaSJeff Mahoney root = read_fs_root(fs_info, 24445d4f98a2SYan Zheng reloc_root->root_key.offset); 24455d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 24465d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 24475d4f98a2SYan Zheng 24483fd0a558SYan, Zheng ret = merge_reloc_root(rc, root); 244900246528SJosef Bacik btrfs_put_root(root); 2450b37b39cdSJosef Bacik if (ret) { 245125e293c2SWang Shilong if (list_empty(&reloc_root->root_list)) 245225e293c2SWang Shilong list_add_tail(&reloc_root->root_list, 245325e293c2SWang Shilong &reloc_roots); 2454aca1bba6SLiu Bo goto out; 2455b37b39cdSJosef Bacik } 24563fd0a558SYan, Zheng } else { 24573fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 245830d40577SQu Wenruo /* Don't forget to queue this reloc root for cleanup */ 245930d40577SQu Wenruo list_add_tail(&reloc_root->reloc_dirty_list, 246030d40577SQu Wenruo &rc->dirty_subvol_roots); 24613fd0a558SYan, Zheng } 24625d4f98a2SYan Zheng } 24635d4f98a2SYan Zheng 24643fd0a558SYan, Zheng if (found) { 24653fd0a558SYan, Zheng found = 0; 24663fd0a558SYan, Zheng goto again; 24675d4f98a2SYan Zheng } 2468aca1bba6SLiu Bo out: 2469aca1bba6SLiu Bo if (ret) { 24700b246afaSJeff Mahoney btrfs_handle_fs_error(fs_info, ret, NULL); 2471aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 2472aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 2473467bb1d2SWang Shilong 2474467bb1d2SWang Shilong /* new reloc root may be added */ 24750b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 2476467bb1d2SWang Shilong list_splice_init(&rc->reloc_roots, &reloc_roots); 24770b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 2478467bb1d2SWang Shilong if (!list_empty(&reloc_roots)) 2479467bb1d2SWang Shilong free_reloc_roots(&reloc_roots); 2480aca1bba6SLiu Bo } 2481aca1bba6SLiu Bo 24827b7b7431SJosef Bacik /* 24837b7b7431SJosef Bacik * We used to have 24847b7b7431SJosef Bacik * 24857b7b7431SJosef Bacik * BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); 24867b7b7431SJosef Bacik * 24877b7b7431SJosef Bacik * here, but it's wrong. If we fail to start the transaction in 24887b7b7431SJosef Bacik * prepare_to_merge() we will have only 0 ref reloc roots, none of which 24897b7b7431SJosef Bacik * have actually been removed from the reloc_root_tree rb tree. This is 24907b7b7431SJosef Bacik * fine because we're bailing here, and we hold a reference on the root 24917b7b7431SJosef Bacik * for the list that holds it, so these roots will be cleaned up when we 24927b7b7431SJosef Bacik * do the reloc_dirty_list afterwards. Meanwhile the root->reloc_root 24937b7b7431SJosef Bacik * will be cleaned up on unmount. 24947b7b7431SJosef Bacik * 24957b7b7431SJosef Bacik * The remaining nodes will be cleaned up by free_reloc_control. 24967b7b7431SJosef Bacik */ 24975d4f98a2SYan Zheng } 24985d4f98a2SYan Zheng 24995d4f98a2SYan Zheng static void free_block_list(struct rb_root *blocks) 25005d4f98a2SYan Zheng { 25015d4f98a2SYan Zheng struct tree_block *block; 25025d4f98a2SYan Zheng struct rb_node *rb_node; 25035d4f98a2SYan Zheng while ((rb_node = rb_first(blocks))) { 25045d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 25055d4f98a2SYan Zheng rb_erase(rb_node, blocks); 25065d4f98a2SYan Zheng kfree(block); 25075d4f98a2SYan Zheng } 25085d4f98a2SYan Zheng } 25095d4f98a2SYan Zheng 25105d4f98a2SYan Zheng static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, 25115d4f98a2SYan Zheng struct btrfs_root *reloc_root) 25125d4f98a2SYan Zheng { 25130b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = reloc_root->fs_info; 25145d4f98a2SYan Zheng struct btrfs_root *root; 2515442b1ac5SJosef Bacik int ret; 25165d4f98a2SYan Zheng 25175d4f98a2SYan Zheng if (reloc_root->last_trans == trans->transid) 25185d4f98a2SYan Zheng return 0; 25195d4f98a2SYan Zheng 25200b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 25215d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 25225d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 2523442b1ac5SJosef Bacik ret = btrfs_record_root_in_trans(trans, root); 252400246528SJosef Bacik btrfs_put_root(root); 25255d4f98a2SYan Zheng 2526442b1ac5SJosef Bacik return ret; 25275d4f98a2SYan Zheng } 25285d4f98a2SYan Zheng 25293fd0a558SYan, Zheng static noinline_for_stack 25303fd0a558SYan, Zheng struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, 25313fd0a558SYan, Zheng struct reloc_control *rc, 2532a26195a5SQu Wenruo struct btrfs_backref_node *node, 2533a26195a5SQu Wenruo struct btrfs_backref_edge *edges[]) 25345d4f98a2SYan Zheng { 2535a26195a5SQu Wenruo struct btrfs_backref_node *next; 25365d4f98a2SYan Zheng struct btrfs_root *root; 25373fd0a558SYan, Zheng int index = 0; 25383fd0a558SYan, Zheng 25395d4f98a2SYan Zheng next = node; 25405d4f98a2SYan Zheng while (1) { 25415d4f98a2SYan Zheng cond_resched(); 25425d4f98a2SYan Zheng next = walk_up_backref(next, edges, &index); 25435d4f98a2SYan Zheng root = next->root; 25443fd0a558SYan, Zheng BUG_ON(!root); 254527cdeb70SMiao Xie BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS, &root->state)); 25465d4f98a2SYan Zheng 25475d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { 25485d4f98a2SYan Zheng record_reloc_root_in_trans(trans, root); 25495d4f98a2SYan Zheng break; 25505d4f98a2SYan Zheng } 25515d4f98a2SYan Zheng 25525d4f98a2SYan Zheng btrfs_record_root_in_trans(trans, root); 25533fd0a558SYan, Zheng root = root->reloc_root; 25543fd0a558SYan, Zheng 25553fd0a558SYan, Zheng if (next->new_bytenr != root->node->start) { 25563fd0a558SYan, Zheng BUG_ON(next->new_bytenr); 25573fd0a558SYan, Zheng BUG_ON(!list_empty(&next->list)); 25583fd0a558SYan, Zheng next->new_bytenr = root->node->start; 255900246528SJosef Bacik btrfs_put_root(next->root); 256000246528SJosef Bacik next->root = btrfs_grab_root(root); 25610b530bc5SJosef Bacik ASSERT(next->root); 25623fd0a558SYan, Zheng list_add_tail(&next->list, 25633fd0a558SYan, Zheng &rc->backref_cache.changed); 25649569cc20SQu Wenruo mark_block_processed(rc, next); 25655d4f98a2SYan Zheng break; 25665d4f98a2SYan Zheng } 25675d4f98a2SYan Zheng 25683fd0a558SYan, Zheng WARN_ON(1); 25695d4f98a2SYan Zheng root = NULL; 25705d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 25715d4f98a2SYan Zheng if (!next || next->level <= node->level) 25725d4f98a2SYan Zheng break; 25735d4f98a2SYan Zheng } 25743fd0a558SYan, Zheng if (!root) 25753fd0a558SYan, Zheng return NULL; 25765d4f98a2SYan Zheng 25773fd0a558SYan, Zheng next = node; 25783fd0a558SYan, Zheng /* setup backref node path for btrfs_reloc_cow_block */ 25793fd0a558SYan, Zheng while (1) { 25803fd0a558SYan, Zheng rc->backref_cache.path[next->level] = next; 25813fd0a558SYan, Zheng if (--index < 0) 25823fd0a558SYan, Zheng break; 25833fd0a558SYan, Zheng next = edges[index]->node[UPPER]; 25843fd0a558SYan, Zheng } 25855d4f98a2SYan Zheng return root; 25865d4f98a2SYan Zheng } 25875d4f98a2SYan Zheng 25883fd0a558SYan, Zheng /* 25893fd0a558SYan, Zheng * select a tree root for relocation. return NULL if the block 25903fd0a558SYan, Zheng * is reference counted. we should use do_relocation() in this 25913fd0a558SYan, Zheng * case. return a tree root pointer if the block isn't reference 25923fd0a558SYan, Zheng * counted. return -ENOENT if the block is root of reloc tree. 25933fd0a558SYan, Zheng */ 25945d4f98a2SYan Zheng static noinline_for_stack 2595a26195a5SQu Wenruo struct btrfs_root *select_one_root(struct btrfs_backref_node *node) 25965d4f98a2SYan Zheng { 2597a26195a5SQu Wenruo struct btrfs_backref_node *next; 25983fd0a558SYan, Zheng struct btrfs_root *root; 25993fd0a558SYan, Zheng struct btrfs_root *fs_root = NULL; 2600a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 26013fd0a558SYan, Zheng int index = 0; 26023fd0a558SYan, Zheng 26033fd0a558SYan, Zheng next = node; 26043fd0a558SYan, Zheng while (1) { 26053fd0a558SYan, Zheng cond_resched(); 26063fd0a558SYan, Zheng next = walk_up_backref(next, edges, &index); 26073fd0a558SYan, Zheng root = next->root; 26083fd0a558SYan, Zheng BUG_ON(!root); 26093fd0a558SYan, Zheng 261025985edcSLucas De Marchi /* no other choice for non-references counted tree */ 261127cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 26123fd0a558SYan, Zheng return root; 26133fd0a558SYan, Zheng 26143fd0a558SYan, Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) 26153fd0a558SYan, Zheng fs_root = root; 26163fd0a558SYan, Zheng 26173fd0a558SYan, Zheng if (next != node) 26183fd0a558SYan, Zheng return NULL; 26193fd0a558SYan, Zheng 26203fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 26213fd0a558SYan, Zheng if (!next || next->level <= node->level) 26223fd0a558SYan, Zheng break; 26233fd0a558SYan, Zheng } 26243fd0a558SYan, Zheng 26253fd0a558SYan, Zheng if (!fs_root) 26263fd0a558SYan, Zheng return ERR_PTR(-ENOENT); 26273fd0a558SYan, Zheng return fs_root; 26285d4f98a2SYan Zheng } 26295d4f98a2SYan Zheng 26305d4f98a2SYan Zheng static noinline_for_stack 26313fd0a558SYan, Zheng u64 calcu_metadata_size(struct reloc_control *rc, 2632a26195a5SQu Wenruo struct btrfs_backref_node *node, int reserve) 26335d4f98a2SYan Zheng { 26340b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 2635a26195a5SQu Wenruo struct btrfs_backref_node *next = node; 2636a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2637a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 26383fd0a558SYan, Zheng u64 num_bytes = 0; 26393fd0a558SYan, Zheng int index = 0; 26405d4f98a2SYan Zheng 26413fd0a558SYan, Zheng BUG_ON(reserve && node->processed); 26423fd0a558SYan, Zheng 26433fd0a558SYan, Zheng while (next) { 26443fd0a558SYan, Zheng cond_resched(); 26455d4f98a2SYan Zheng while (1) { 26463fd0a558SYan, Zheng if (next->processed && (reserve || next != node)) 26475d4f98a2SYan Zheng break; 26485d4f98a2SYan Zheng 26490b246afaSJeff Mahoney num_bytes += fs_info->nodesize; 26503fd0a558SYan, Zheng 26513fd0a558SYan, Zheng if (list_empty(&next->upper)) 26523fd0a558SYan, Zheng break; 26533fd0a558SYan, Zheng 26543fd0a558SYan, Zheng edge = list_entry(next->upper.next, 2655a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 26563fd0a558SYan, Zheng edges[index++] = edge; 26573fd0a558SYan, Zheng next = edge->node[UPPER]; 26585d4f98a2SYan Zheng } 26593fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 26603fd0a558SYan, Zheng } 26613fd0a558SYan, Zheng return num_bytes; 26623fd0a558SYan, Zheng } 26633fd0a558SYan, Zheng 26643fd0a558SYan, Zheng static int reserve_metadata_space(struct btrfs_trans_handle *trans, 26653fd0a558SYan, Zheng struct reloc_control *rc, 2666a26195a5SQu Wenruo struct btrfs_backref_node *node) 26673fd0a558SYan, Zheng { 26683fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 2669da17066cSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 26703fd0a558SYan, Zheng u64 num_bytes; 26713fd0a558SYan, Zheng int ret; 26720647bf56SWang Shilong u64 tmp; 26733fd0a558SYan, Zheng 26743fd0a558SYan, Zheng num_bytes = calcu_metadata_size(rc, node, 1) * 2; 26753fd0a558SYan, Zheng 26763fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 26770647bf56SWang Shilong rc->reserved_bytes += num_bytes; 26788ca17f0fSJosef Bacik 26798ca17f0fSJosef Bacik /* 26808ca17f0fSJosef Bacik * We are under a transaction here so we can only do limited flushing. 26818ca17f0fSJosef Bacik * If we get an enospc just kick back -EAGAIN so we know to drop the 26828ca17f0fSJosef Bacik * transaction and try to refill when we can flush all the things. 26838ca17f0fSJosef Bacik */ 26840647bf56SWang Shilong ret = btrfs_block_rsv_refill(root, rc->block_rsv, num_bytes, 26858ca17f0fSJosef Bacik BTRFS_RESERVE_FLUSH_LIMIT); 26863fd0a558SYan, Zheng if (ret) { 2687da17066cSJeff Mahoney tmp = fs_info->nodesize * RELOCATION_RESERVED_NODES; 26880647bf56SWang Shilong while (tmp <= rc->reserved_bytes) 26890647bf56SWang Shilong tmp <<= 1; 26900647bf56SWang Shilong /* 26910647bf56SWang Shilong * only one thread can access block_rsv at this point, 26920647bf56SWang Shilong * so we don't need hold lock to protect block_rsv. 26930647bf56SWang Shilong * we expand more reservation size here to allow enough 269452042d8eSAndrea Gelmini * space for relocation and we will return earlier in 26950647bf56SWang Shilong * enospc case. 26960647bf56SWang Shilong */ 2697da17066cSJeff Mahoney rc->block_rsv->size = tmp + fs_info->nodesize * 26980647bf56SWang Shilong RELOCATION_RESERVED_NODES; 26998ca17f0fSJosef Bacik return -EAGAIN; 27003fd0a558SYan, Zheng } 27013fd0a558SYan, Zheng 27023fd0a558SYan, Zheng return 0; 27033fd0a558SYan, Zheng } 27043fd0a558SYan, Zheng 27055d4f98a2SYan Zheng /* 27065d4f98a2SYan Zheng * relocate a block tree, and then update pointers in upper level 27075d4f98a2SYan Zheng * blocks that reference the block to point to the new location. 27085d4f98a2SYan Zheng * 27095d4f98a2SYan Zheng * if called by link_to_upper, the block has already been relocated. 27105d4f98a2SYan Zheng * in that case this function just updates pointers. 27115d4f98a2SYan Zheng */ 27125d4f98a2SYan Zheng static int do_relocation(struct btrfs_trans_handle *trans, 27133fd0a558SYan, Zheng struct reloc_control *rc, 2714a26195a5SQu Wenruo struct btrfs_backref_node *node, 27155d4f98a2SYan Zheng struct btrfs_key *key, 27165d4f98a2SYan Zheng struct btrfs_path *path, int lowest) 27175d4f98a2SYan Zheng { 27182ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 2719a26195a5SQu Wenruo struct btrfs_backref_node *upper; 2720a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2721a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 27225d4f98a2SYan Zheng struct btrfs_root *root; 27235d4f98a2SYan Zheng struct extent_buffer *eb; 27245d4f98a2SYan Zheng u32 blocksize; 27255d4f98a2SYan Zheng u64 bytenr; 27265d4f98a2SYan Zheng u64 generation; 27275d4f98a2SYan Zheng int slot; 27285d4f98a2SYan Zheng int ret; 27295d4f98a2SYan Zheng int err = 0; 27305d4f98a2SYan Zheng 27315d4f98a2SYan Zheng BUG_ON(lowest && node->eb); 27325d4f98a2SYan Zheng 27335d4f98a2SYan Zheng path->lowest_level = node->level + 1; 27343fd0a558SYan, Zheng rc->backref_cache.path[node->level] = node; 27355d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) { 2736581c1760SQu Wenruo struct btrfs_key first_key; 273782fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 2738581c1760SQu Wenruo 27395d4f98a2SYan Zheng cond_resched(); 27405d4f98a2SYan Zheng 27415d4f98a2SYan Zheng upper = edge->node[UPPER]; 2742dc4103f9SWang Shilong root = select_reloc_root(trans, rc, upper, edges); 27433fd0a558SYan, Zheng BUG_ON(!root); 27445d4f98a2SYan Zheng 27453fd0a558SYan, Zheng if (upper->eb && !upper->locked) { 27463fd0a558SYan, Zheng if (!lowest) { 27473fd0a558SYan, Zheng ret = btrfs_bin_search(upper->eb, key, 27483fd0a558SYan, Zheng upper->level, &slot); 2749cbca7d59SFilipe Manana if (ret < 0) { 2750cbca7d59SFilipe Manana err = ret; 2751cbca7d59SFilipe Manana goto next; 2752cbca7d59SFilipe Manana } 27533fd0a558SYan, Zheng BUG_ON(ret); 27543fd0a558SYan, Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 27553fd0a558SYan, Zheng if (node->eb->start == bytenr) 27563fd0a558SYan, Zheng goto next; 27573fd0a558SYan, Zheng } 2758b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(upper); 27593fd0a558SYan, Zheng } 27605d4f98a2SYan Zheng 27615d4f98a2SYan Zheng if (!upper->eb) { 27625d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 27633561b9dbSLiu Bo if (ret) { 27643561b9dbSLiu Bo if (ret < 0) 27655d4f98a2SYan Zheng err = ret; 27663561b9dbSLiu Bo else 27673561b9dbSLiu Bo err = -ENOENT; 27683561b9dbSLiu Bo 27693561b9dbSLiu Bo btrfs_release_path(path); 27705d4f98a2SYan Zheng break; 27715d4f98a2SYan Zheng } 27725d4f98a2SYan Zheng 27733fd0a558SYan, Zheng if (!upper->eb) { 27743fd0a558SYan, Zheng upper->eb = path->nodes[upper->level]; 27753fd0a558SYan, Zheng path->nodes[upper->level] = NULL; 27763fd0a558SYan, Zheng } else { 27773fd0a558SYan, Zheng BUG_ON(upper->eb != path->nodes[upper->level]); 27783fd0a558SYan, Zheng } 27793fd0a558SYan, Zheng 27803fd0a558SYan, Zheng upper->locked = 1; 27813fd0a558SYan, Zheng path->locks[upper->level] = 0; 27823fd0a558SYan, Zheng 27835d4f98a2SYan Zheng slot = path->slots[upper->level]; 2784b3b4aa74SDavid Sterba btrfs_release_path(path); 27855d4f98a2SYan Zheng } else { 27865d4f98a2SYan Zheng ret = btrfs_bin_search(upper->eb, key, upper->level, 27875d4f98a2SYan Zheng &slot); 2788cbca7d59SFilipe Manana if (ret < 0) { 2789cbca7d59SFilipe Manana err = ret; 2790cbca7d59SFilipe Manana goto next; 2791cbca7d59SFilipe Manana } 27925d4f98a2SYan Zheng BUG_ON(ret); 27935d4f98a2SYan Zheng } 27945d4f98a2SYan Zheng 27955d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 27963fd0a558SYan, Zheng if (lowest) { 27974547f4d8SLiu Bo if (bytenr != node->bytenr) { 27984547f4d8SLiu Bo btrfs_err(root->fs_info, 27994547f4d8SLiu Bo "lowest leaf/node mismatch: bytenr %llu node->bytenr %llu slot %d upper %llu", 28004547f4d8SLiu Bo bytenr, node->bytenr, slot, 28014547f4d8SLiu Bo upper->eb->start); 28024547f4d8SLiu Bo err = -EIO; 28034547f4d8SLiu Bo goto next; 28044547f4d8SLiu Bo } 28055d4f98a2SYan Zheng } else { 28063fd0a558SYan, Zheng if (node->eb->start == bytenr) 28073fd0a558SYan, Zheng goto next; 28085d4f98a2SYan Zheng } 28095d4f98a2SYan Zheng 2810da17066cSJeff Mahoney blocksize = root->fs_info->nodesize; 28115d4f98a2SYan Zheng generation = btrfs_node_ptr_generation(upper->eb, slot); 2812581c1760SQu Wenruo btrfs_node_key_to_cpu(upper->eb, &first_key, slot); 2813581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, generation, 2814581c1760SQu Wenruo upper->level - 1, &first_key); 281564c043deSLiu Bo if (IS_ERR(eb)) { 281664c043deSLiu Bo err = PTR_ERR(eb); 281764c043deSLiu Bo goto next; 281864c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2819416bc658SJosef Bacik free_extent_buffer(eb); 282097d9a8a4STsutomu Itoh err = -EIO; 282197d9a8a4STsutomu Itoh goto next; 282297d9a8a4STsutomu Itoh } 28235d4f98a2SYan Zheng btrfs_tree_lock(eb); 28248bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 28255d4f98a2SYan Zheng 28265d4f98a2SYan Zheng if (!node->eb) { 28275d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, eb, upper->eb, 28285d4f98a2SYan Zheng slot, &eb); 28293fd0a558SYan, Zheng btrfs_tree_unlock(eb); 28303fd0a558SYan, Zheng free_extent_buffer(eb); 28315d4f98a2SYan Zheng if (ret < 0) { 28325d4f98a2SYan Zheng err = ret; 28333fd0a558SYan, Zheng goto next; 28345d4f98a2SYan Zheng } 28353fd0a558SYan, Zheng BUG_ON(node->eb != eb); 28365d4f98a2SYan Zheng } else { 28375d4f98a2SYan Zheng btrfs_set_node_blockptr(upper->eb, slot, 28385d4f98a2SYan Zheng node->eb->start); 28395d4f98a2SYan Zheng btrfs_set_node_ptr_generation(upper->eb, slot, 28405d4f98a2SYan Zheng trans->transid); 28415d4f98a2SYan Zheng btrfs_mark_buffer_dirty(upper->eb); 28425d4f98a2SYan Zheng 284382fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, 28445d4f98a2SYan Zheng node->eb->start, blocksize, 284582fa113fSQu Wenruo upper->eb->start); 284682fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 284782fa113fSQu Wenruo btrfs_init_tree_ref(&ref, node->level, 284882fa113fSQu Wenruo btrfs_header_owner(upper->eb)); 284982fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 28505d4f98a2SYan Zheng BUG_ON(ret); 28515d4f98a2SYan Zheng 28525d4f98a2SYan Zheng ret = btrfs_drop_subtree(trans, root, eb, upper->eb); 28535d4f98a2SYan Zheng BUG_ON(ret); 28545d4f98a2SYan Zheng } 28553fd0a558SYan, Zheng next: 28563fd0a558SYan, Zheng if (!upper->pending) 2857b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(upper); 28583fd0a558SYan, Zheng else 2859b0fe7078SQu Wenruo btrfs_backref_unlock_node_buffer(upper); 28603fd0a558SYan, Zheng if (err) 28613fd0a558SYan, Zheng break; 28625d4f98a2SYan Zheng } 28633fd0a558SYan, Zheng 28643fd0a558SYan, Zheng if (!err && node->pending) { 2865b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(node); 28663fd0a558SYan, Zheng list_move_tail(&node->list, &rc->backref_cache.changed); 28673fd0a558SYan, Zheng node->pending = 0; 28685d4f98a2SYan Zheng } 28693fd0a558SYan, Zheng 28705d4f98a2SYan Zheng path->lowest_level = 0; 28713fd0a558SYan, Zheng BUG_ON(err == -ENOSPC); 28725d4f98a2SYan Zheng return err; 28735d4f98a2SYan Zheng } 28745d4f98a2SYan Zheng 28755d4f98a2SYan Zheng static int link_to_upper(struct btrfs_trans_handle *trans, 28763fd0a558SYan, Zheng struct reloc_control *rc, 2877a26195a5SQu Wenruo struct btrfs_backref_node *node, 28785d4f98a2SYan Zheng struct btrfs_path *path) 28795d4f98a2SYan Zheng { 28805d4f98a2SYan Zheng struct btrfs_key key; 28815d4f98a2SYan Zheng 28825d4f98a2SYan Zheng btrfs_node_key_to_cpu(node->eb, &key, 0); 28833fd0a558SYan, Zheng return do_relocation(trans, rc, node, &key, path, 0); 28845d4f98a2SYan Zheng } 28855d4f98a2SYan Zheng 28865d4f98a2SYan Zheng static int finish_pending_nodes(struct btrfs_trans_handle *trans, 28873fd0a558SYan, Zheng struct reloc_control *rc, 28883fd0a558SYan, Zheng struct btrfs_path *path, int err) 28895d4f98a2SYan Zheng { 28903fd0a558SYan, Zheng LIST_HEAD(list); 2891a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 2892a26195a5SQu Wenruo struct btrfs_backref_node *node; 28935d4f98a2SYan Zheng int level; 28945d4f98a2SYan Zheng int ret; 28955d4f98a2SYan Zheng 28965d4f98a2SYan Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 28975d4f98a2SYan Zheng while (!list_empty(&cache->pending[level])) { 28985d4f98a2SYan Zheng node = list_entry(cache->pending[level].next, 2899a26195a5SQu Wenruo struct btrfs_backref_node, list); 29003fd0a558SYan, Zheng list_move_tail(&node->list, &list); 29013fd0a558SYan, Zheng BUG_ON(!node->pending); 29025d4f98a2SYan Zheng 29033fd0a558SYan, Zheng if (!err) { 29043fd0a558SYan, Zheng ret = link_to_upper(trans, rc, node, path); 29055d4f98a2SYan Zheng if (ret < 0) 29065d4f98a2SYan Zheng err = ret; 29075d4f98a2SYan Zheng } 29085d4f98a2SYan Zheng } 29093fd0a558SYan, Zheng list_splice_init(&list, &cache->pending[level]); 29103fd0a558SYan, Zheng } 29115d4f98a2SYan Zheng return err; 29125d4f98a2SYan Zheng } 29135d4f98a2SYan Zheng 29145d4f98a2SYan Zheng /* 29155d4f98a2SYan Zheng * mark a block and all blocks directly/indirectly reference the block 29165d4f98a2SYan Zheng * as processed. 29175d4f98a2SYan Zheng */ 29185d4f98a2SYan Zheng static void update_processed_blocks(struct reloc_control *rc, 2919a26195a5SQu Wenruo struct btrfs_backref_node *node) 29205d4f98a2SYan Zheng { 2921a26195a5SQu Wenruo struct btrfs_backref_node *next = node; 2922a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2923a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 29245d4f98a2SYan Zheng int index = 0; 29255d4f98a2SYan Zheng 29265d4f98a2SYan Zheng while (next) { 29275d4f98a2SYan Zheng cond_resched(); 29285d4f98a2SYan Zheng while (1) { 29295d4f98a2SYan Zheng if (next->processed) 29305d4f98a2SYan Zheng break; 29315d4f98a2SYan Zheng 29329569cc20SQu Wenruo mark_block_processed(rc, next); 29335d4f98a2SYan Zheng 29345d4f98a2SYan Zheng if (list_empty(&next->upper)) 29355d4f98a2SYan Zheng break; 29365d4f98a2SYan Zheng 29375d4f98a2SYan Zheng edge = list_entry(next->upper.next, 2938a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 29395d4f98a2SYan Zheng edges[index++] = edge; 29405d4f98a2SYan Zheng next = edge->node[UPPER]; 29415d4f98a2SYan Zheng } 29425d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 29435d4f98a2SYan Zheng } 29445d4f98a2SYan Zheng } 29455d4f98a2SYan Zheng 29467476dfdaSDavid Sterba static int tree_block_processed(u64 bytenr, struct reloc_control *rc) 29475d4f98a2SYan Zheng { 2948da17066cSJeff Mahoney u32 blocksize = rc->extent_root->fs_info->nodesize; 29497476dfdaSDavid Sterba 29505d4f98a2SYan Zheng if (test_range_bit(&rc->processed_blocks, bytenr, 29519655d298SChris Mason bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) 29525d4f98a2SYan Zheng return 1; 29535d4f98a2SYan Zheng return 0; 29545d4f98a2SYan Zheng } 29555d4f98a2SYan Zheng 29562ff7e61eSJeff Mahoney static int get_tree_block_key(struct btrfs_fs_info *fs_info, 29575d4f98a2SYan Zheng struct tree_block *block) 29585d4f98a2SYan Zheng { 29595d4f98a2SYan Zheng struct extent_buffer *eb; 29605d4f98a2SYan Zheng 2961581c1760SQu Wenruo eb = read_tree_block(fs_info, block->bytenr, block->key.offset, 2962581c1760SQu Wenruo block->level, NULL); 296364c043deSLiu Bo if (IS_ERR(eb)) { 296464c043deSLiu Bo return PTR_ERR(eb); 296564c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2966416bc658SJosef Bacik free_extent_buffer(eb); 2967416bc658SJosef Bacik return -EIO; 2968416bc658SJosef Bacik } 29695d4f98a2SYan Zheng if (block->level == 0) 29705d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &block->key, 0); 29715d4f98a2SYan Zheng else 29725d4f98a2SYan Zheng btrfs_node_key_to_cpu(eb, &block->key, 0); 29735d4f98a2SYan Zheng free_extent_buffer(eb); 29745d4f98a2SYan Zheng block->key_ready = 1; 29755d4f98a2SYan Zheng return 0; 29765d4f98a2SYan Zheng } 29775d4f98a2SYan Zheng 29785d4f98a2SYan Zheng /* 29795d4f98a2SYan Zheng * helper function to relocate a tree block 29805d4f98a2SYan Zheng */ 29815d4f98a2SYan Zheng static int relocate_tree_block(struct btrfs_trans_handle *trans, 29825d4f98a2SYan Zheng struct reloc_control *rc, 2983a26195a5SQu Wenruo struct btrfs_backref_node *node, 29845d4f98a2SYan Zheng struct btrfs_key *key, 29855d4f98a2SYan Zheng struct btrfs_path *path) 29865d4f98a2SYan Zheng { 29875d4f98a2SYan Zheng struct btrfs_root *root; 29883fd0a558SYan, Zheng int ret = 0; 29895d4f98a2SYan Zheng 29903fd0a558SYan, Zheng if (!node) 29915d4f98a2SYan Zheng return 0; 29923fd0a558SYan, Zheng 29935f6b2e5cSJosef Bacik /* 29945f6b2e5cSJosef Bacik * If we fail here we want to drop our backref_node because we are going 29955f6b2e5cSJosef Bacik * to start over and regenerate the tree for it. 29965f6b2e5cSJosef Bacik */ 29975f6b2e5cSJosef Bacik ret = reserve_metadata_space(trans, rc, node); 29985f6b2e5cSJosef Bacik if (ret) 29995f6b2e5cSJosef Bacik goto out; 30005f6b2e5cSJosef Bacik 30013fd0a558SYan, Zheng BUG_ON(node->processed); 3002147d256eSZhaolei root = select_one_root(node); 30033fd0a558SYan, Zheng if (root == ERR_PTR(-ENOENT)) { 30043fd0a558SYan, Zheng update_processed_blocks(rc, node); 30053fd0a558SYan, Zheng goto out; 30065d4f98a2SYan Zheng } 30075d4f98a2SYan Zheng 30083fd0a558SYan, Zheng if (root) { 300927cdeb70SMiao Xie if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) { 30103fd0a558SYan, Zheng BUG_ON(node->new_bytenr); 30113fd0a558SYan, Zheng BUG_ON(!list_empty(&node->list)); 30123fd0a558SYan, Zheng btrfs_record_root_in_trans(trans, root); 30133fd0a558SYan, Zheng root = root->reloc_root; 30143fd0a558SYan, Zheng node->new_bytenr = root->node->start; 301500246528SJosef Bacik btrfs_put_root(node->root); 301600246528SJosef Bacik node->root = btrfs_grab_root(root); 30170b530bc5SJosef Bacik ASSERT(node->root); 30183fd0a558SYan, Zheng list_add_tail(&node->list, &rc->backref_cache.changed); 30193fd0a558SYan, Zheng } else { 30205d4f98a2SYan Zheng path->lowest_level = node->level; 30215d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 3022b3b4aa74SDavid Sterba btrfs_release_path(path); 30233fd0a558SYan, Zheng if (ret > 0) 30245d4f98a2SYan Zheng ret = 0; 30253fd0a558SYan, Zheng } 30263fd0a558SYan, Zheng if (!ret) 30273fd0a558SYan, Zheng update_processed_blocks(rc, node); 30283fd0a558SYan, Zheng } else { 30293fd0a558SYan, Zheng ret = do_relocation(trans, rc, node, key, path, 1); 30303fd0a558SYan, Zheng } 30315d4f98a2SYan Zheng out: 30320647bf56SWang Shilong if (ret || node->level == 0 || node->cowonly) 3033023acb07SQu Wenruo btrfs_backref_cleanup_node(&rc->backref_cache, node); 30345d4f98a2SYan Zheng return ret; 30355d4f98a2SYan Zheng } 30365d4f98a2SYan Zheng 30375d4f98a2SYan Zheng /* 30385d4f98a2SYan Zheng * relocate a list of blocks 30395d4f98a2SYan Zheng */ 30405d4f98a2SYan Zheng static noinline_for_stack 30415d4f98a2SYan Zheng int relocate_tree_blocks(struct btrfs_trans_handle *trans, 30425d4f98a2SYan Zheng struct reloc_control *rc, struct rb_root *blocks) 30435d4f98a2SYan Zheng { 30442ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 3045a26195a5SQu Wenruo struct btrfs_backref_node *node; 30465d4f98a2SYan Zheng struct btrfs_path *path; 30475d4f98a2SYan Zheng struct tree_block *block; 304898ff7b94SQu Wenruo struct tree_block *next; 30495d4f98a2SYan Zheng int ret; 30505d4f98a2SYan Zheng int err = 0; 30515d4f98a2SYan Zheng 30525d4f98a2SYan Zheng path = btrfs_alloc_path(); 3053e1a12670SLiu Bo if (!path) { 3054e1a12670SLiu Bo err = -ENOMEM; 305534c2b290SDavid Sterba goto out_free_blocks; 3056e1a12670SLiu Bo } 30575d4f98a2SYan Zheng 305898ff7b94SQu Wenruo /* Kick in readahead for tree blocks with missing keys */ 305998ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 30605d4f98a2SYan Zheng if (!block->key_ready) 30612ff7e61eSJeff Mahoney readahead_tree_block(fs_info, block->bytenr); 30625d4f98a2SYan Zheng } 30635d4f98a2SYan Zheng 306498ff7b94SQu Wenruo /* Get first keys */ 306598ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 306634c2b290SDavid Sterba if (!block->key_ready) { 30672ff7e61eSJeff Mahoney err = get_tree_block_key(fs_info, block); 306834c2b290SDavid Sterba if (err) 306934c2b290SDavid Sterba goto out_free_path; 307034c2b290SDavid Sterba } 30715d4f98a2SYan Zheng } 30725d4f98a2SYan Zheng 307398ff7b94SQu Wenruo /* Do tree relocation */ 307498ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 30753fd0a558SYan, Zheng node = build_backref_tree(rc, &block->key, 30765d4f98a2SYan Zheng block->level, block->bytenr); 30775d4f98a2SYan Zheng if (IS_ERR(node)) { 30785d4f98a2SYan Zheng err = PTR_ERR(node); 30795d4f98a2SYan Zheng goto out; 30805d4f98a2SYan Zheng } 30815d4f98a2SYan Zheng 30825d4f98a2SYan Zheng ret = relocate_tree_block(trans, rc, node, &block->key, 30835d4f98a2SYan Zheng path); 30845d4f98a2SYan Zheng if (ret < 0) { 30855d4f98a2SYan Zheng err = ret; 308650dbbb71SJosef Bacik break; 30875d4f98a2SYan Zheng } 30885d4f98a2SYan Zheng } 30895d4f98a2SYan Zheng out: 30903fd0a558SYan, Zheng err = finish_pending_nodes(trans, rc, path, err); 30915d4f98a2SYan Zheng 309234c2b290SDavid Sterba out_free_path: 30935d4f98a2SYan Zheng btrfs_free_path(path); 309434c2b290SDavid Sterba out_free_blocks: 3095e1a12670SLiu Bo free_block_list(blocks); 30965d4f98a2SYan Zheng return err; 30975d4f98a2SYan Zheng } 30985d4f98a2SYan Zheng 30995d4f98a2SYan Zheng static noinline_for_stack 3100efa56464SYan, Zheng int prealloc_file_extent_cluster(struct inode *inode, 3101efa56464SYan, Zheng struct file_extent_cluster *cluster) 3102efa56464SYan, Zheng { 3103efa56464SYan, Zheng u64 alloc_hint = 0; 3104efa56464SYan, Zheng u64 start; 3105efa56464SYan, Zheng u64 end; 3106efa56464SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 3107efa56464SYan, Zheng u64 num_bytes; 3108efa56464SYan, Zheng int nr = 0; 3109efa56464SYan, Zheng int ret = 0; 3110dcb40c19SWang Xiaoguang u64 prealloc_start = cluster->start - offset; 3111dcb40c19SWang Xiaoguang u64 prealloc_end = cluster->end - offset; 311218513091SWang Xiaoguang u64 cur_offset; 3113364ecf36SQu Wenruo struct extent_changeset *data_reserved = NULL; 3114efa56464SYan, Zheng 3115efa56464SYan, Zheng BUG_ON(cluster->start != cluster->boundary[0]); 31165955102cSAl Viro inode_lock(inode); 3117efa56464SYan, Zheng 3118364ecf36SQu Wenruo ret = btrfs_check_data_free_space(inode, &data_reserved, prealloc_start, 3119dcb40c19SWang Xiaoguang prealloc_end + 1 - prealloc_start); 3120efa56464SYan, Zheng if (ret) 3121efa56464SYan, Zheng goto out; 3122efa56464SYan, Zheng 312318513091SWang Xiaoguang cur_offset = prealloc_start; 3124efa56464SYan, Zheng while (nr < cluster->nr) { 3125efa56464SYan, Zheng start = cluster->boundary[nr] - offset; 3126efa56464SYan, Zheng if (nr + 1 < cluster->nr) 3127efa56464SYan, Zheng end = cluster->boundary[nr + 1] - 1 - offset; 3128efa56464SYan, Zheng else 3129efa56464SYan, Zheng end = cluster->end - offset; 3130efa56464SYan, Zheng 3131d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 3132efa56464SYan, Zheng num_bytes = end + 1 - start; 313318513091SWang Xiaoguang if (cur_offset < start) 3134bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3135bc42bda2SQu Wenruo cur_offset, start - cur_offset); 3136efa56464SYan, Zheng ret = btrfs_prealloc_file_range(inode, 0, start, 3137efa56464SYan, Zheng num_bytes, num_bytes, 3138efa56464SYan, Zheng end + 1, &alloc_hint); 313918513091SWang Xiaoguang cur_offset = end + 1; 3140d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 3141efa56464SYan, Zheng if (ret) 3142efa56464SYan, Zheng break; 3143efa56464SYan, Zheng nr++; 3144efa56464SYan, Zheng } 314518513091SWang Xiaoguang if (cur_offset < prealloc_end) 3146bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3147bc42bda2SQu Wenruo cur_offset, prealloc_end + 1 - cur_offset); 3148efa56464SYan, Zheng out: 31495955102cSAl Viro inode_unlock(inode); 3150364ecf36SQu Wenruo extent_changeset_free(data_reserved); 3151efa56464SYan, Zheng return ret; 3152efa56464SYan, Zheng } 3153efa56464SYan, Zheng 3154efa56464SYan, Zheng static noinline_for_stack 31550257bb82SYan, Zheng int setup_extent_mapping(struct inode *inode, u64 start, u64 end, 31560257bb82SYan, Zheng u64 block_start) 31575d4f98a2SYan Zheng { 31585d4f98a2SYan Zheng struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 31595d4f98a2SYan Zheng struct extent_map *em; 31600257bb82SYan, Zheng int ret = 0; 31615d4f98a2SYan Zheng 3162172ddd60SDavid Sterba em = alloc_extent_map(); 31630257bb82SYan, Zheng if (!em) 31640257bb82SYan, Zheng return -ENOMEM; 31650257bb82SYan, Zheng 31665d4f98a2SYan Zheng em->start = start; 31670257bb82SYan, Zheng em->len = end + 1 - start; 31680257bb82SYan, Zheng em->block_len = em->len; 31690257bb82SYan, Zheng em->block_start = block_start; 31705d4f98a2SYan Zheng set_bit(EXTENT_FLAG_PINNED, &em->flags); 31715d4f98a2SYan Zheng 3172d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 31735d4f98a2SYan Zheng while (1) { 3174890871beSChris Mason write_lock(&em_tree->lock); 317509a2a8f9SJosef Bacik ret = add_extent_mapping(em_tree, em, 0); 3176890871beSChris Mason write_unlock(&em_tree->lock); 31775d4f98a2SYan Zheng if (ret != -EEXIST) { 31785d4f98a2SYan Zheng free_extent_map(em); 31795d4f98a2SYan Zheng break; 31805d4f98a2SYan Zheng } 3181dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); 31825d4f98a2SYan Zheng } 3183d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 31840257bb82SYan, Zheng return ret; 31850257bb82SYan, Zheng } 31865d4f98a2SYan Zheng 3187726a3421SQu Wenruo /* 3188726a3421SQu Wenruo * Allow error injection to test balance cancellation 3189726a3421SQu Wenruo */ 3190726a3421SQu Wenruo int btrfs_should_cancel_balance(struct btrfs_fs_info *fs_info) 3191726a3421SQu Wenruo { 3192726a3421SQu Wenruo return atomic_read(&fs_info->balance_cancel_req); 3193726a3421SQu Wenruo } 3194726a3421SQu Wenruo ALLOW_ERROR_INJECTION(btrfs_should_cancel_balance, TRUE); 3195726a3421SQu Wenruo 31960257bb82SYan, Zheng static int relocate_file_extent_cluster(struct inode *inode, 31970257bb82SYan, Zheng struct file_extent_cluster *cluster) 31980257bb82SYan, Zheng { 31992ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 32000257bb82SYan, Zheng u64 page_start; 32010257bb82SYan, Zheng u64 page_end; 32020257bb82SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 32030257bb82SYan, Zheng unsigned long index; 32040257bb82SYan, Zheng unsigned long last_index; 32050257bb82SYan, Zheng struct page *page; 32060257bb82SYan, Zheng struct file_ra_state *ra; 32073b16a4e3SJosef Bacik gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 32080257bb82SYan, Zheng int nr = 0; 32090257bb82SYan, Zheng int ret = 0; 32100257bb82SYan, Zheng 32110257bb82SYan, Zheng if (!cluster->nr) 32120257bb82SYan, Zheng return 0; 32130257bb82SYan, Zheng 32140257bb82SYan, Zheng ra = kzalloc(sizeof(*ra), GFP_NOFS); 32150257bb82SYan, Zheng if (!ra) 32160257bb82SYan, Zheng return -ENOMEM; 32170257bb82SYan, Zheng 3218efa56464SYan, Zheng ret = prealloc_file_extent_cluster(inode, cluster); 32190257bb82SYan, Zheng if (ret) 3220efa56464SYan, Zheng goto out; 32210257bb82SYan, Zheng 32220257bb82SYan, Zheng file_ra_state_init(ra, inode->i_mapping); 32230257bb82SYan, Zheng 3224efa56464SYan, Zheng ret = setup_extent_mapping(inode, cluster->start - offset, 3225efa56464SYan, Zheng cluster->end - offset, cluster->start); 3226efa56464SYan, Zheng if (ret) 3227efa56464SYan, Zheng goto out; 3228efa56464SYan, Zheng 322909cbfeafSKirill A. Shutemov index = (cluster->start - offset) >> PAGE_SHIFT; 323009cbfeafSKirill A. Shutemov last_index = (cluster->end - offset) >> PAGE_SHIFT; 32310257bb82SYan, Zheng while (index <= last_index) { 32329f3db423SNikolay Borisov ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), 32339f3db423SNikolay Borisov PAGE_SIZE); 3234efa56464SYan, Zheng if (ret) 3235efa56464SYan, Zheng goto out; 3236efa56464SYan, Zheng 32370257bb82SYan, Zheng page = find_lock_page(inode->i_mapping, index); 32380257bb82SYan, Zheng if (!page) { 32390257bb82SYan, Zheng page_cache_sync_readahead(inode->i_mapping, 32400257bb82SYan, Zheng ra, NULL, index, 32410257bb82SYan, Zheng last_index + 1 - index); 3242a94733d0SJosef Bacik page = find_or_create_page(inode->i_mapping, index, 32433b16a4e3SJosef Bacik mask); 32440257bb82SYan, Zheng if (!page) { 3245691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 324643b18595SQu Wenruo PAGE_SIZE, true); 324744db1216SFilipe Manana btrfs_delalloc_release_extents(BTRFS_I(inode), 32488702ba93SQu Wenruo PAGE_SIZE); 32490257bb82SYan, Zheng ret = -ENOMEM; 3250efa56464SYan, Zheng goto out; 32510257bb82SYan, Zheng } 32520257bb82SYan, Zheng } 32530257bb82SYan, Zheng 32540257bb82SYan, Zheng if (PageReadahead(page)) { 32550257bb82SYan, Zheng page_cache_async_readahead(inode->i_mapping, 32560257bb82SYan, Zheng ra, NULL, page, index, 32570257bb82SYan, Zheng last_index + 1 - index); 32580257bb82SYan, Zheng } 32590257bb82SYan, Zheng 32600257bb82SYan, Zheng if (!PageUptodate(page)) { 32610257bb82SYan, Zheng btrfs_readpage(NULL, page); 32620257bb82SYan, Zheng lock_page(page); 32630257bb82SYan, Zheng if (!PageUptodate(page)) { 32640257bb82SYan, Zheng unlock_page(page); 326509cbfeafSKirill A. Shutemov put_page(page); 3266691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 326743b18595SQu Wenruo PAGE_SIZE, true); 32688b62f87bSJosef Bacik btrfs_delalloc_release_extents(BTRFS_I(inode), 32698702ba93SQu Wenruo PAGE_SIZE); 32700257bb82SYan, Zheng ret = -EIO; 3271efa56464SYan, Zheng goto out; 32720257bb82SYan, Zheng } 32730257bb82SYan, Zheng } 32740257bb82SYan, Zheng 32754eee4fa4SMiao Xie page_start = page_offset(page); 327609cbfeafSKirill A. Shutemov page_end = page_start + PAGE_SIZE - 1; 32770257bb82SYan, Zheng 3278d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end); 32790257bb82SYan, Zheng 32800257bb82SYan, Zheng set_page_extent_mapped(page); 32810257bb82SYan, Zheng 32820257bb82SYan, Zheng if (nr < cluster->nr && 32830257bb82SYan, Zheng page_start + offset == cluster->boundary[nr]) { 32840257bb82SYan, Zheng set_extent_bits(&BTRFS_I(inode)->io_tree, 32850257bb82SYan, Zheng page_start, page_end, 3286ceeb0ae7SDavid Sterba EXTENT_BOUNDARY); 32870257bb82SYan, Zheng nr++; 32880257bb82SYan, Zheng } 32890257bb82SYan, Zheng 3290765f3cebSNikolay Borisov ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, 3291330a5827SNikolay Borisov NULL); 3292765f3cebSNikolay Borisov if (ret) { 3293765f3cebSNikolay Borisov unlock_page(page); 3294765f3cebSNikolay Borisov put_page(page); 3295765f3cebSNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 329643b18595SQu Wenruo PAGE_SIZE, true); 3297765f3cebSNikolay Borisov btrfs_delalloc_release_extents(BTRFS_I(inode), 32988702ba93SQu Wenruo PAGE_SIZE); 3299765f3cebSNikolay Borisov 3300765f3cebSNikolay Borisov clear_extent_bits(&BTRFS_I(inode)->io_tree, 3301765f3cebSNikolay Borisov page_start, page_end, 3302765f3cebSNikolay Borisov EXTENT_LOCKED | EXTENT_BOUNDARY); 3303765f3cebSNikolay Borisov goto out; 3304765f3cebSNikolay Borisov 3305765f3cebSNikolay Borisov } 33060257bb82SYan, Zheng set_page_dirty(page); 33070257bb82SYan, Zheng 33080257bb82SYan, Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 3309d0082371SJeff Mahoney page_start, page_end); 33100257bb82SYan, Zheng unlock_page(page); 331109cbfeafSKirill A. Shutemov put_page(page); 33120257bb82SYan, Zheng 33130257bb82SYan, Zheng index++; 33148702ba93SQu Wenruo btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); 3315efa56464SYan, Zheng balance_dirty_pages_ratelimited(inode->i_mapping); 33162ff7e61eSJeff Mahoney btrfs_throttle(fs_info); 33177f913c7cSQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 33187f913c7cSQu Wenruo ret = -ECANCELED; 33197f913c7cSQu Wenruo goto out; 33207f913c7cSQu Wenruo } 33210257bb82SYan, Zheng } 33220257bb82SYan, Zheng WARN_ON(nr != cluster->nr); 3323efa56464SYan, Zheng out: 33240257bb82SYan, Zheng kfree(ra); 33250257bb82SYan, Zheng return ret; 33260257bb82SYan, Zheng } 33270257bb82SYan, Zheng 33280257bb82SYan, Zheng static noinline_for_stack 33290257bb82SYan, Zheng int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, 33300257bb82SYan, Zheng struct file_extent_cluster *cluster) 33310257bb82SYan, Zheng { 33320257bb82SYan, Zheng int ret; 33330257bb82SYan, Zheng 33340257bb82SYan, Zheng if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) { 33350257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 33360257bb82SYan, Zheng if (ret) 33370257bb82SYan, Zheng return ret; 33380257bb82SYan, Zheng cluster->nr = 0; 33390257bb82SYan, Zheng } 33400257bb82SYan, Zheng 33410257bb82SYan, Zheng if (!cluster->nr) 33420257bb82SYan, Zheng cluster->start = extent_key->objectid; 33430257bb82SYan, Zheng else 33440257bb82SYan, Zheng BUG_ON(cluster->nr >= MAX_EXTENTS); 33450257bb82SYan, Zheng cluster->end = extent_key->objectid + extent_key->offset - 1; 33460257bb82SYan, Zheng cluster->boundary[cluster->nr] = extent_key->objectid; 33470257bb82SYan, Zheng cluster->nr++; 33480257bb82SYan, Zheng 33490257bb82SYan, Zheng if (cluster->nr >= MAX_EXTENTS) { 33500257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 33510257bb82SYan, Zheng if (ret) 33520257bb82SYan, Zheng return ret; 33530257bb82SYan, Zheng cluster->nr = 0; 33540257bb82SYan, Zheng } 33550257bb82SYan, Zheng return 0; 33565d4f98a2SYan Zheng } 33575d4f98a2SYan Zheng 33585d4f98a2SYan Zheng /* 33595d4f98a2SYan Zheng * helper to add a tree block to the list. 33605d4f98a2SYan Zheng * the major work is getting the generation and level of the block 33615d4f98a2SYan Zheng */ 33625d4f98a2SYan Zheng static int add_tree_block(struct reloc_control *rc, 33635d4f98a2SYan Zheng struct btrfs_key *extent_key, 33645d4f98a2SYan Zheng struct btrfs_path *path, 33655d4f98a2SYan Zheng struct rb_root *blocks) 33665d4f98a2SYan Zheng { 33675d4f98a2SYan Zheng struct extent_buffer *eb; 33685d4f98a2SYan Zheng struct btrfs_extent_item *ei; 33695d4f98a2SYan Zheng struct btrfs_tree_block_info *bi; 33705d4f98a2SYan Zheng struct tree_block *block; 33715d4f98a2SYan Zheng struct rb_node *rb_node; 33725d4f98a2SYan Zheng u32 item_size; 33735d4f98a2SYan Zheng int level = -1; 33747fdf4b60SWang Shilong u64 generation; 33755d4f98a2SYan Zheng 33765d4f98a2SYan Zheng eb = path->nodes[0]; 33775d4f98a2SYan Zheng item_size = btrfs_item_size_nr(eb, path->slots[0]); 33785d4f98a2SYan Zheng 33793173a18fSJosef Bacik if (extent_key->type == BTRFS_METADATA_ITEM_KEY || 33803173a18fSJosef Bacik item_size >= sizeof(*ei) + sizeof(*bi)) { 33815d4f98a2SYan Zheng ei = btrfs_item_ptr(eb, path->slots[0], 33825d4f98a2SYan Zheng struct btrfs_extent_item); 33833173a18fSJosef Bacik if (extent_key->type == BTRFS_EXTENT_ITEM_KEY) { 33845d4f98a2SYan Zheng bi = (struct btrfs_tree_block_info *)(ei + 1); 33855d4f98a2SYan Zheng level = btrfs_tree_block_level(eb, bi); 33865d4f98a2SYan Zheng } else { 33873173a18fSJosef Bacik level = (int)extent_key->offset; 33883173a18fSJosef Bacik } 33893173a18fSJosef Bacik generation = btrfs_extent_generation(eb, ei); 33906d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3391ba3c2b19SNikolay Borisov btrfs_print_v0_err(eb->fs_info); 3392ba3c2b19SNikolay Borisov btrfs_handle_fs_error(eb->fs_info, -EINVAL, NULL); 3393ba3c2b19SNikolay Borisov return -EINVAL; 33943173a18fSJosef Bacik } else { 33955d4f98a2SYan Zheng BUG(); 33965d4f98a2SYan Zheng } 33975d4f98a2SYan Zheng 3398b3b4aa74SDavid Sterba btrfs_release_path(path); 33995d4f98a2SYan Zheng 34005d4f98a2SYan Zheng BUG_ON(level == -1); 34015d4f98a2SYan Zheng 34025d4f98a2SYan Zheng block = kmalloc(sizeof(*block), GFP_NOFS); 34035d4f98a2SYan Zheng if (!block) 34045d4f98a2SYan Zheng return -ENOMEM; 34055d4f98a2SYan Zheng 34065d4f98a2SYan Zheng block->bytenr = extent_key->objectid; 3407da17066cSJeff Mahoney block->key.objectid = rc->extent_root->fs_info->nodesize; 34085d4f98a2SYan Zheng block->key.offset = generation; 34095d4f98a2SYan Zheng block->level = level; 34105d4f98a2SYan Zheng block->key_ready = 0; 34115d4f98a2SYan Zheng 3412e9a28dc5SQu Wenruo rb_node = rb_simple_insert(blocks, block->bytenr, &block->rb_node); 341343c04fb1SJeff Mahoney if (rb_node) 341443c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, block->bytenr); 34155d4f98a2SYan Zheng 34165d4f98a2SYan Zheng return 0; 34175d4f98a2SYan Zheng } 34185d4f98a2SYan Zheng 34195d4f98a2SYan Zheng /* 34205d4f98a2SYan Zheng * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY 34215d4f98a2SYan Zheng */ 34225d4f98a2SYan Zheng static int __add_tree_block(struct reloc_control *rc, 34235d4f98a2SYan Zheng u64 bytenr, u32 blocksize, 34245d4f98a2SYan Zheng struct rb_root *blocks) 34255d4f98a2SYan Zheng { 34260b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 34275d4f98a2SYan Zheng struct btrfs_path *path; 34285d4f98a2SYan Zheng struct btrfs_key key; 34295d4f98a2SYan Zheng int ret; 34300b246afaSJeff Mahoney bool skinny = btrfs_fs_incompat(fs_info, SKINNY_METADATA); 34315d4f98a2SYan Zheng 34327476dfdaSDavid Sterba if (tree_block_processed(bytenr, rc)) 34335d4f98a2SYan Zheng return 0; 34345d4f98a2SYan Zheng 3435e9a28dc5SQu Wenruo if (rb_simple_search(blocks, bytenr)) 34365d4f98a2SYan Zheng return 0; 34375d4f98a2SYan Zheng 34385d4f98a2SYan Zheng path = btrfs_alloc_path(); 34395d4f98a2SYan Zheng if (!path) 34405d4f98a2SYan Zheng return -ENOMEM; 3441aee68ee5SJosef Bacik again: 34425d4f98a2SYan Zheng key.objectid = bytenr; 3443aee68ee5SJosef Bacik if (skinny) { 3444aee68ee5SJosef Bacik key.type = BTRFS_METADATA_ITEM_KEY; 3445aee68ee5SJosef Bacik key.offset = (u64)-1; 3446aee68ee5SJosef Bacik } else { 34475d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 34485d4f98a2SYan Zheng key.offset = blocksize; 3449aee68ee5SJosef Bacik } 34505d4f98a2SYan Zheng 34515d4f98a2SYan Zheng path->search_commit_root = 1; 34525d4f98a2SYan Zheng path->skip_locking = 1; 34535d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); 34545d4f98a2SYan Zheng if (ret < 0) 34555d4f98a2SYan Zheng goto out; 34565d4f98a2SYan Zheng 3457aee68ee5SJosef Bacik if (ret > 0 && skinny) { 3458aee68ee5SJosef Bacik if (path->slots[0]) { 3459aee68ee5SJosef Bacik path->slots[0]--; 3460aee68ee5SJosef Bacik btrfs_item_key_to_cpu(path->nodes[0], &key, 3461aee68ee5SJosef Bacik path->slots[0]); 34623173a18fSJosef Bacik if (key.objectid == bytenr && 3463aee68ee5SJosef Bacik (key.type == BTRFS_METADATA_ITEM_KEY || 3464aee68ee5SJosef Bacik (key.type == BTRFS_EXTENT_ITEM_KEY && 3465aee68ee5SJosef Bacik key.offset == blocksize))) 34663173a18fSJosef Bacik ret = 0; 34673173a18fSJosef Bacik } 3468aee68ee5SJosef Bacik 3469aee68ee5SJosef Bacik if (ret) { 3470aee68ee5SJosef Bacik skinny = false; 3471aee68ee5SJosef Bacik btrfs_release_path(path); 3472aee68ee5SJosef Bacik goto again; 3473aee68ee5SJosef Bacik } 3474aee68ee5SJosef Bacik } 3475cdccee99SLiu Bo if (ret) { 3476cdccee99SLiu Bo ASSERT(ret == 1); 3477cdccee99SLiu Bo btrfs_print_leaf(path->nodes[0]); 3478cdccee99SLiu Bo btrfs_err(fs_info, 3479cdccee99SLiu Bo "tree block extent item (%llu) is not found in extent tree", 3480cdccee99SLiu Bo bytenr); 3481cdccee99SLiu Bo WARN_ON(1); 3482cdccee99SLiu Bo ret = -EINVAL; 3483cdccee99SLiu Bo goto out; 3484cdccee99SLiu Bo } 34853173a18fSJosef Bacik 34865d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, blocks); 34875d4f98a2SYan Zheng out: 34885d4f98a2SYan Zheng btrfs_free_path(path); 34895d4f98a2SYan Zheng return ret; 34905d4f98a2SYan Zheng } 34915d4f98a2SYan Zheng 34920af3d00bSJosef Bacik static int delete_block_group_cache(struct btrfs_fs_info *fs_info, 349332da5386SDavid Sterba struct btrfs_block_group *block_group, 34941bbc621eSChris Mason struct inode *inode, 34951bbc621eSChris Mason u64 ino) 34960af3d00bSJosef Bacik { 34970af3d00bSJosef Bacik struct btrfs_key key; 34980af3d00bSJosef Bacik struct btrfs_root *root = fs_info->tree_root; 34990af3d00bSJosef Bacik struct btrfs_trans_handle *trans; 35000af3d00bSJosef Bacik int ret = 0; 35010af3d00bSJosef Bacik 35020af3d00bSJosef Bacik if (inode) 35030af3d00bSJosef Bacik goto truncate; 35040af3d00bSJosef Bacik 35050af3d00bSJosef Bacik key.objectid = ino; 35060af3d00bSJosef Bacik key.type = BTRFS_INODE_ITEM_KEY; 35070af3d00bSJosef Bacik key.offset = 0; 35080af3d00bSJosef Bacik 35094c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 35102e19f1f9SAl Viro if (IS_ERR(inode)) 35110af3d00bSJosef Bacik return -ENOENT; 35120af3d00bSJosef Bacik 35130af3d00bSJosef Bacik truncate: 35142ff7e61eSJeff Mahoney ret = btrfs_check_trunc_cache_free_space(fs_info, 35157b61cd92SMiao Xie &fs_info->global_block_rsv); 35167b61cd92SMiao Xie if (ret) 35177b61cd92SMiao Xie goto out; 35187b61cd92SMiao Xie 35197a7eaa40SJosef Bacik trans = btrfs_join_transaction(root); 35200af3d00bSJosef Bacik if (IS_ERR(trans)) { 35213612b495STsutomu Itoh ret = PTR_ERR(trans); 35220af3d00bSJosef Bacik goto out; 35230af3d00bSJosef Bacik } 35240af3d00bSJosef Bacik 352577ab86bfSJeff Mahoney ret = btrfs_truncate_free_space_cache(trans, block_group, inode); 35260af3d00bSJosef Bacik 35273a45bb20SJeff Mahoney btrfs_end_transaction(trans); 35282ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 35290af3d00bSJosef Bacik out: 35300af3d00bSJosef Bacik iput(inode); 35310af3d00bSJosef Bacik return ret; 35320af3d00bSJosef Bacik } 35330af3d00bSJosef Bacik 35345d4f98a2SYan Zheng /* 353519b546d7SQu Wenruo * Locate the free space cache EXTENT_DATA in root tree leaf and delete the 353619b546d7SQu Wenruo * cache inode, to avoid free space cache data extent blocking data relocation. 35375d4f98a2SYan Zheng */ 353819b546d7SQu Wenruo static int delete_v1_space_cache(struct extent_buffer *leaf, 353919b546d7SQu Wenruo struct btrfs_block_group *block_group, 354019b546d7SQu Wenruo u64 data_bytenr) 35415d4f98a2SYan Zheng { 354219b546d7SQu Wenruo u64 space_cache_ino; 354319b546d7SQu Wenruo struct btrfs_file_extent_item *ei; 35445d4f98a2SYan Zheng struct btrfs_key key; 354519b546d7SQu Wenruo bool found = false; 354619b546d7SQu Wenruo int i; 35475d4f98a2SYan Zheng int ret; 35485d4f98a2SYan Zheng 354919b546d7SQu Wenruo if (btrfs_header_owner(leaf) != BTRFS_ROOT_TREE_OBJECTID) 355019b546d7SQu Wenruo return 0; 35515d4f98a2SYan Zheng 355219b546d7SQu Wenruo for (i = 0; i < btrfs_header_nritems(leaf); i++) { 355319b546d7SQu Wenruo btrfs_item_key_to_cpu(leaf, &key, i); 355419b546d7SQu Wenruo if (key.type != BTRFS_EXTENT_DATA_KEY) 355519b546d7SQu Wenruo continue; 355619b546d7SQu Wenruo ei = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 355719b546d7SQu Wenruo if (btrfs_file_extent_type(leaf, ei) == BTRFS_FILE_EXTENT_REG && 355819b546d7SQu Wenruo btrfs_file_extent_disk_bytenr(leaf, ei) == data_bytenr) { 355919b546d7SQu Wenruo found = true; 356019b546d7SQu Wenruo space_cache_ino = key.objectid; 356119b546d7SQu Wenruo break; 356219b546d7SQu Wenruo } 356319b546d7SQu Wenruo } 356419b546d7SQu Wenruo if (!found) 356519b546d7SQu Wenruo return -ENOENT; 356619b546d7SQu Wenruo ret = delete_block_group_cache(leaf->fs_info, block_group, NULL, 356719b546d7SQu Wenruo space_cache_ino); 35680af3d00bSJosef Bacik return ret; 35695d4f98a2SYan Zheng } 35705d4f98a2SYan Zheng 35715d4f98a2SYan Zheng /* 35722c016dc2SLiu Bo * helper to find all tree blocks that reference a given data extent 35735d4f98a2SYan Zheng */ 35745d4f98a2SYan Zheng static noinline_for_stack 35755d4f98a2SYan Zheng int add_data_references(struct reloc_control *rc, 35765d4f98a2SYan Zheng struct btrfs_key *extent_key, 35775d4f98a2SYan Zheng struct btrfs_path *path, 35785d4f98a2SYan Zheng struct rb_root *blocks) 35795d4f98a2SYan Zheng { 358019b546d7SQu Wenruo struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 358119b546d7SQu Wenruo struct ulist *leaves = NULL; 358219b546d7SQu Wenruo struct ulist_iterator leaf_uiter; 358319b546d7SQu Wenruo struct ulist_node *ref_node = NULL; 358419b546d7SQu Wenruo const u32 blocksize = fs_info->nodesize; 3585647f63bdSFilipe David Borba Manana int ret = 0; 35865d4f98a2SYan Zheng 3587b3b4aa74SDavid Sterba btrfs_release_path(path); 358819b546d7SQu Wenruo ret = btrfs_find_all_leafs(NULL, fs_info, extent_key->objectid, 358919b546d7SQu Wenruo 0, &leaves, NULL, true); 359019b546d7SQu Wenruo if (ret < 0) 359119b546d7SQu Wenruo return ret; 359219b546d7SQu Wenruo 359319b546d7SQu Wenruo ULIST_ITER_INIT(&leaf_uiter); 359419b546d7SQu Wenruo while ((ref_node = ulist_next(leaves, &leaf_uiter))) { 359519b546d7SQu Wenruo struct extent_buffer *eb; 359619b546d7SQu Wenruo 359719b546d7SQu Wenruo eb = read_tree_block(fs_info, ref_node->val, 0, 0, NULL); 359819b546d7SQu Wenruo if (IS_ERR(eb)) { 359919b546d7SQu Wenruo ret = PTR_ERR(eb); 360019b546d7SQu Wenruo break; 360119b546d7SQu Wenruo } 360219b546d7SQu Wenruo ret = delete_v1_space_cache(eb, rc->block_group, 360319b546d7SQu Wenruo extent_key->objectid); 360419b546d7SQu Wenruo free_extent_buffer(eb); 360519b546d7SQu Wenruo if (ret < 0) 360619b546d7SQu Wenruo break; 360719b546d7SQu Wenruo ret = __add_tree_block(rc, ref_node->val, blocksize, blocks); 360819b546d7SQu Wenruo if (ret < 0) 360919b546d7SQu Wenruo break; 361019b546d7SQu Wenruo } 361119b546d7SQu Wenruo if (ret < 0) 36125d4f98a2SYan Zheng free_block_list(blocks); 361319b546d7SQu Wenruo ulist_free(leaves); 361419b546d7SQu Wenruo return ret; 36155d4f98a2SYan Zheng } 36165d4f98a2SYan Zheng 36175d4f98a2SYan Zheng /* 36182c016dc2SLiu Bo * helper to find next unprocessed extent 36195d4f98a2SYan Zheng */ 36205d4f98a2SYan Zheng static noinline_for_stack 3621147d256eSZhaolei int find_next_extent(struct reloc_control *rc, struct btrfs_path *path, 36223fd0a558SYan, Zheng struct btrfs_key *extent_key) 36235d4f98a2SYan Zheng { 36240b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 36255d4f98a2SYan Zheng struct btrfs_key key; 36265d4f98a2SYan Zheng struct extent_buffer *leaf; 36275d4f98a2SYan Zheng u64 start, end, last; 36285d4f98a2SYan Zheng int ret; 36295d4f98a2SYan Zheng 3630b3470b5dSDavid Sterba last = rc->block_group->start + rc->block_group->length; 36315d4f98a2SYan Zheng while (1) { 36325d4f98a2SYan Zheng cond_resched(); 36335d4f98a2SYan Zheng if (rc->search_start >= last) { 36345d4f98a2SYan Zheng ret = 1; 36355d4f98a2SYan Zheng break; 36365d4f98a2SYan Zheng } 36375d4f98a2SYan Zheng 36385d4f98a2SYan Zheng key.objectid = rc->search_start; 36395d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 36405d4f98a2SYan Zheng key.offset = 0; 36415d4f98a2SYan Zheng 36425d4f98a2SYan Zheng path->search_commit_root = 1; 36435d4f98a2SYan Zheng path->skip_locking = 1; 36445d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 36455d4f98a2SYan Zheng 0, 0); 36465d4f98a2SYan Zheng if (ret < 0) 36475d4f98a2SYan Zheng break; 36485d4f98a2SYan Zheng next: 36495d4f98a2SYan Zheng leaf = path->nodes[0]; 36505d4f98a2SYan Zheng if (path->slots[0] >= btrfs_header_nritems(leaf)) { 36515d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 36525d4f98a2SYan Zheng if (ret != 0) 36535d4f98a2SYan Zheng break; 36545d4f98a2SYan Zheng leaf = path->nodes[0]; 36555d4f98a2SYan Zheng } 36565d4f98a2SYan Zheng 36575d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 36585d4f98a2SYan Zheng if (key.objectid >= last) { 36595d4f98a2SYan Zheng ret = 1; 36605d4f98a2SYan Zheng break; 36615d4f98a2SYan Zheng } 36625d4f98a2SYan Zheng 36633173a18fSJosef Bacik if (key.type != BTRFS_EXTENT_ITEM_KEY && 36643173a18fSJosef Bacik key.type != BTRFS_METADATA_ITEM_KEY) { 36653173a18fSJosef Bacik path->slots[0]++; 36663173a18fSJosef Bacik goto next; 36673173a18fSJosef Bacik } 36683173a18fSJosef Bacik 36693173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY && 36705d4f98a2SYan Zheng key.objectid + key.offset <= rc->search_start) { 36715d4f98a2SYan Zheng path->slots[0]++; 36725d4f98a2SYan Zheng goto next; 36735d4f98a2SYan Zheng } 36745d4f98a2SYan Zheng 36753173a18fSJosef Bacik if (key.type == BTRFS_METADATA_ITEM_KEY && 36760b246afaSJeff Mahoney key.objectid + fs_info->nodesize <= 36773173a18fSJosef Bacik rc->search_start) { 36783173a18fSJosef Bacik path->slots[0]++; 36793173a18fSJosef Bacik goto next; 36803173a18fSJosef Bacik } 36813173a18fSJosef Bacik 36825d4f98a2SYan Zheng ret = find_first_extent_bit(&rc->processed_blocks, 36835d4f98a2SYan Zheng key.objectid, &start, &end, 3684e6138876SJosef Bacik EXTENT_DIRTY, NULL); 36855d4f98a2SYan Zheng 36865d4f98a2SYan Zheng if (ret == 0 && start <= key.objectid) { 3687b3b4aa74SDavid Sterba btrfs_release_path(path); 36885d4f98a2SYan Zheng rc->search_start = end + 1; 36895d4f98a2SYan Zheng } else { 36903173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY) 36915d4f98a2SYan Zheng rc->search_start = key.objectid + key.offset; 36923173a18fSJosef Bacik else 36933173a18fSJosef Bacik rc->search_start = key.objectid + 36940b246afaSJeff Mahoney fs_info->nodesize; 36953fd0a558SYan, Zheng memcpy(extent_key, &key, sizeof(key)); 36965d4f98a2SYan Zheng return 0; 36975d4f98a2SYan Zheng } 36985d4f98a2SYan Zheng } 3699b3b4aa74SDavid Sterba btrfs_release_path(path); 37005d4f98a2SYan Zheng return ret; 37015d4f98a2SYan Zheng } 37025d4f98a2SYan Zheng 37035d4f98a2SYan Zheng static void set_reloc_control(struct reloc_control *rc) 37045d4f98a2SYan Zheng { 37055d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37067585717fSChris Mason 37077585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 37085d4f98a2SYan Zheng fs_info->reloc_ctl = rc; 37097585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 37105d4f98a2SYan Zheng } 37115d4f98a2SYan Zheng 37125d4f98a2SYan Zheng static void unset_reloc_control(struct reloc_control *rc) 37135d4f98a2SYan Zheng { 37145d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37157585717fSChris Mason 37167585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 37175d4f98a2SYan Zheng fs_info->reloc_ctl = NULL; 37187585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 37195d4f98a2SYan Zheng } 37205d4f98a2SYan Zheng 37215d4f98a2SYan Zheng static int check_extent_flags(u64 flags) 37225d4f98a2SYan Zheng { 37235d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 37245d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 37255d4f98a2SYan Zheng return 1; 37265d4f98a2SYan Zheng if (!(flags & BTRFS_EXTENT_FLAG_DATA) && 37275d4f98a2SYan Zheng !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 37285d4f98a2SYan Zheng return 1; 37295d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 37305d4f98a2SYan Zheng (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) 37315d4f98a2SYan Zheng return 1; 37325d4f98a2SYan Zheng return 0; 37335d4f98a2SYan Zheng } 37345d4f98a2SYan Zheng 37353fd0a558SYan, Zheng static noinline_for_stack 37363fd0a558SYan, Zheng int prepare_to_relocate(struct reloc_control *rc) 37373fd0a558SYan, Zheng { 37383fd0a558SYan, Zheng struct btrfs_trans_handle *trans; 3739ac2fabacSJosef Bacik int ret; 37403fd0a558SYan, Zheng 37412ff7e61eSJeff Mahoney rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root->fs_info, 374266d8f3ddSMiao Xie BTRFS_BLOCK_RSV_TEMP); 37433fd0a558SYan, Zheng if (!rc->block_rsv) 37443fd0a558SYan, Zheng return -ENOMEM; 37453fd0a558SYan, Zheng 37463fd0a558SYan, Zheng memset(&rc->cluster, 0, sizeof(rc->cluster)); 3747b3470b5dSDavid Sterba rc->search_start = rc->block_group->start; 37483fd0a558SYan, Zheng rc->extents_found = 0; 37493fd0a558SYan, Zheng rc->nodes_relocated = 0; 37503fd0a558SYan, Zheng rc->merging_rsv_size = 0; 37510647bf56SWang Shilong rc->reserved_bytes = 0; 3752da17066cSJeff Mahoney rc->block_rsv->size = rc->extent_root->fs_info->nodesize * 37530647bf56SWang Shilong RELOCATION_RESERVED_NODES; 3754ac2fabacSJosef Bacik ret = btrfs_block_rsv_refill(rc->extent_root, 3755ac2fabacSJosef Bacik rc->block_rsv, rc->block_rsv->size, 3756ac2fabacSJosef Bacik BTRFS_RESERVE_FLUSH_ALL); 3757ac2fabacSJosef Bacik if (ret) 3758ac2fabacSJosef Bacik return ret; 37593fd0a558SYan, Zheng 37603fd0a558SYan, Zheng rc->create_reloc_tree = 1; 37613fd0a558SYan, Zheng set_reloc_control(rc); 37623fd0a558SYan, Zheng 37637a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 376428818947SLiu Bo if (IS_ERR(trans)) { 376528818947SLiu Bo unset_reloc_control(rc); 376628818947SLiu Bo /* 376728818947SLiu Bo * extent tree is not a ref_cow tree and has no reloc_root to 376828818947SLiu Bo * cleanup. And callers are responsible to free the above 376928818947SLiu Bo * block rsv. 377028818947SLiu Bo */ 377128818947SLiu Bo return PTR_ERR(trans); 377228818947SLiu Bo } 37733a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 37743fd0a558SYan, Zheng return 0; 37753fd0a558SYan, Zheng } 377676dda93cSYan, Zheng 37775d4f98a2SYan Zheng static noinline_for_stack int relocate_block_group(struct reloc_control *rc) 37785d4f98a2SYan Zheng { 37792ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37805d4f98a2SYan Zheng struct rb_root blocks = RB_ROOT; 37815d4f98a2SYan Zheng struct btrfs_key key; 37825d4f98a2SYan Zheng struct btrfs_trans_handle *trans = NULL; 37835d4f98a2SYan Zheng struct btrfs_path *path; 37845d4f98a2SYan Zheng struct btrfs_extent_item *ei; 37855d4f98a2SYan Zheng u64 flags; 37865d4f98a2SYan Zheng u32 item_size; 37875d4f98a2SYan Zheng int ret; 37885d4f98a2SYan Zheng int err = 0; 3789c87f08caSChris Mason int progress = 0; 37905d4f98a2SYan Zheng 37915d4f98a2SYan Zheng path = btrfs_alloc_path(); 37923fd0a558SYan, Zheng if (!path) 37935d4f98a2SYan Zheng return -ENOMEM; 3794e4058b54SDavid Sterba path->reada = READA_FORWARD; 37953fd0a558SYan, Zheng 37963fd0a558SYan, Zheng ret = prepare_to_relocate(rc); 37973fd0a558SYan, Zheng if (ret) { 37983fd0a558SYan, Zheng err = ret; 37993fd0a558SYan, Zheng goto out_free; 38002423fdfbSJiri Slaby } 38015d4f98a2SYan Zheng 38025d4f98a2SYan Zheng while (1) { 38030647bf56SWang Shilong rc->reserved_bytes = 0; 38040647bf56SWang Shilong ret = btrfs_block_rsv_refill(rc->extent_root, 38050647bf56SWang Shilong rc->block_rsv, rc->block_rsv->size, 38060647bf56SWang Shilong BTRFS_RESERVE_FLUSH_ALL); 38070647bf56SWang Shilong if (ret) { 38080647bf56SWang Shilong err = ret; 38090647bf56SWang Shilong break; 38100647bf56SWang Shilong } 3811c87f08caSChris Mason progress++; 3812a22285a6SYan, Zheng trans = btrfs_start_transaction(rc->extent_root, 0); 38130f788c58SLiu Bo if (IS_ERR(trans)) { 38140f788c58SLiu Bo err = PTR_ERR(trans); 38150f788c58SLiu Bo trans = NULL; 38160f788c58SLiu Bo break; 38170f788c58SLiu Bo } 3818c87f08caSChris Mason restart: 38193fd0a558SYan, Zheng if (update_backref_cache(trans, &rc->backref_cache)) { 38203a45bb20SJeff Mahoney btrfs_end_transaction(trans); 382142a657f5SPan Bian trans = NULL; 38223fd0a558SYan, Zheng continue; 38233fd0a558SYan, Zheng } 38243fd0a558SYan, Zheng 3825147d256eSZhaolei ret = find_next_extent(rc, path, &key); 38265d4f98a2SYan Zheng if (ret < 0) 38275d4f98a2SYan Zheng err = ret; 38285d4f98a2SYan Zheng if (ret != 0) 38295d4f98a2SYan Zheng break; 38305d4f98a2SYan Zheng 38315d4f98a2SYan Zheng rc->extents_found++; 38325d4f98a2SYan Zheng 38335d4f98a2SYan Zheng ei = btrfs_item_ptr(path->nodes[0], path->slots[0], 38345d4f98a2SYan Zheng struct btrfs_extent_item); 38353fd0a558SYan, Zheng item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); 38365d4f98a2SYan Zheng if (item_size >= sizeof(*ei)) { 38375d4f98a2SYan Zheng flags = btrfs_extent_flags(path->nodes[0], ei); 38385d4f98a2SYan Zheng ret = check_extent_flags(flags); 38395d4f98a2SYan Zheng BUG_ON(ret); 38406d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3841ba3c2b19SNikolay Borisov err = -EINVAL; 3842ba3c2b19SNikolay Borisov btrfs_print_v0_err(trans->fs_info); 3843ba3c2b19SNikolay Borisov btrfs_abort_transaction(trans, err); 3844ba3c2b19SNikolay Borisov break; 38455d4f98a2SYan Zheng } else { 38465d4f98a2SYan Zheng BUG(); 38475d4f98a2SYan Zheng } 38485d4f98a2SYan Zheng 38495d4f98a2SYan Zheng if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 38505d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, &blocks); 38515d4f98a2SYan Zheng } else if (rc->stage == UPDATE_DATA_PTRS && 38525d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 38535d4f98a2SYan Zheng ret = add_data_references(rc, &key, path, &blocks); 38545d4f98a2SYan Zheng } else { 3855b3b4aa74SDavid Sterba btrfs_release_path(path); 38565d4f98a2SYan Zheng ret = 0; 38575d4f98a2SYan Zheng } 38585d4f98a2SYan Zheng if (ret < 0) { 38593fd0a558SYan, Zheng err = ret; 38605d4f98a2SYan Zheng break; 38615d4f98a2SYan Zheng } 38625d4f98a2SYan Zheng 38635d4f98a2SYan Zheng if (!RB_EMPTY_ROOT(&blocks)) { 38645d4f98a2SYan Zheng ret = relocate_tree_blocks(trans, rc, &blocks); 38655d4f98a2SYan Zheng if (ret < 0) { 38663fd0a558SYan, Zheng if (ret != -EAGAIN) { 38675d4f98a2SYan Zheng err = ret; 38685d4f98a2SYan Zheng break; 38695d4f98a2SYan Zheng } 38703fd0a558SYan, Zheng rc->extents_found--; 38713fd0a558SYan, Zheng rc->search_start = key.objectid; 38723fd0a558SYan, Zheng } 38735d4f98a2SYan Zheng } 38745d4f98a2SYan Zheng 38753a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 38762ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 38773fd0a558SYan, Zheng trans = NULL; 38785d4f98a2SYan Zheng 38795d4f98a2SYan Zheng if (rc->stage == MOVE_DATA_EXTENTS && 38805d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 38815d4f98a2SYan Zheng rc->found_file_extent = 1; 38820257bb82SYan, Zheng ret = relocate_data_extent(rc->data_inode, 38833fd0a558SYan, Zheng &key, &rc->cluster); 38845d4f98a2SYan Zheng if (ret < 0) { 38855d4f98a2SYan Zheng err = ret; 38865d4f98a2SYan Zheng break; 38875d4f98a2SYan Zheng } 38885d4f98a2SYan Zheng } 3889f31ea088SQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 3890f31ea088SQu Wenruo err = -ECANCELED; 3891f31ea088SQu Wenruo break; 3892f31ea088SQu Wenruo } 38935d4f98a2SYan Zheng } 3894c87f08caSChris Mason if (trans && progress && err == -ENOSPC) { 389543a7e99dSNikolay Borisov ret = btrfs_force_chunk_alloc(trans, rc->block_group->flags); 38969689457bSShilong Wang if (ret == 1) { 3897c87f08caSChris Mason err = 0; 3898c87f08caSChris Mason progress = 0; 3899c87f08caSChris Mason goto restart; 3900c87f08caSChris Mason } 3901c87f08caSChris Mason } 39023fd0a558SYan, Zheng 3903b3b4aa74SDavid Sterba btrfs_release_path(path); 390491166212SDavid Sterba clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY); 39055d4f98a2SYan Zheng 39065d4f98a2SYan Zheng if (trans) { 39073a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 39082ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 39095d4f98a2SYan Zheng } 39105d4f98a2SYan Zheng 39110257bb82SYan, Zheng if (!err) { 39123fd0a558SYan, Zheng ret = relocate_file_extent_cluster(rc->data_inode, 39133fd0a558SYan, Zheng &rc->cluster); 39140257bb82SYan, Zheng if (ret < 0) 39150257bb82SYan, Zheng err = ret; 39160257bb82SYan, Zheng } 39170257bb82SYan, Zheng 39183fd0a558SYan, Zheng rc->create_reloc_tree = 0; 39193fd0a558SYan, Zheng set_reloc_control(rc); 39200257bb82SYan, Zheng 392113fe1bdbSQu Wenruo btrfs_backref_release_cache(&rc->backref_cache); 392263f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 39235d4f98a2SYan Zheng 39247f913c7cSQu Wenruo /* 39257f913c7cSQu Wenruo * Even in the case when the relocation is cancelled, we should all go 39267f913c7cSQu Wenruo * through prepare_to_merge() and merge_reloc_roots(). 39277f913c7cSQu Wenruo * 39287f913c7cSQu Wenruo * For error (including cancelled balance), prepare_to_merge() will 39297f913c7cSQu Wenruo * mark all reloc trees orphan, then queue them for cleanup in 39307f913c7cSQu Wenruo * merge_reloc_roots() 39317f913c7cSQu Wenruo */ 39323fd0a558SYan, Zheng err = prepare_to_merge(rc, err); 39335d4f98a2SYan Zheng 39345d4f98a2SYan Zheng merge_reloc_roots(rc); 39355d4f98a2SYan Zheng 39363fd0a558SYan, Zheng rc->merge_reloc_tree = 0; 39375d4f98a2SYan Zheng unset_reloc_control(rc); 393863f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 39395d4f98a2SYan Zheng 39405d4f98a2SYan Zheng /* get rid of pinned extents */ 39417a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 394262b99540SQu Wenruo if (IS_ERR(trans)) { 39433612b495STsutomu Itoh err = PTR_ERR(trans); 394462b99540SQu Wenruo goto out_free; 394562b99540SQu Wenruo } 39463a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 39476217b0faSJosef Bacik out_free: 3948d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 3949d2311e69SQu Wenruo if (ret < 0 && !err) 3950d2311e69SQu Wenruo err = ret; 39512ff7e61eSJeff Mahoney btrfs_free_block_rsv(fs_info, rc->block_rsv); 39523fd0a558SYan, Zheng btrfs_free_path(path); 39535d4f98a2SYan Zheng return err; 39545d4f98a2SYan Zheng } 39555d4f98a2SYan Zheng 39565d4f98a2SYan Zheng static int __insert_orphan_inode(struct btrfs_trans_handle *trans, 39570257bb82SYan, Zheng struct btrfs_root *root, u64 objectid) 39585d4f98a2SYan Zheng { 39595d4f98a2SYan Zheng struct btrfs_path *path; 39605d4f98a2SYan Zheng struct btrfs_inode_item *item; 39615d4f98a2SYan Zheng struct extent_buffer *leaf; 39625d4f98a2SYan Zheng int ret; 39635d4f98a2SYan Zheng 39645d4f98a2SYan Zheng path = btrfs_alloc_path(); 39655d4f98a2SYan Zheng if (!path) 39665d4f98a2SYan Zheng return -ENOMEM; 39675d4f98a2SYan Zheng 39685d4f98a2SYan Zheng ret = btrfs_insert_empty_inode(trans, root, path, objectid); 39695d4f98a2SYan Zheng if (ret) 39705d4f98a2SYan Zheng goto out; 39715d4f98a2SYan Zheng 39725d4f98a2SYan Zheng leaf = path->nodes[0]; 39735d4f98a2SYan Zheng item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); 3974b159fa28SDavid Sterba memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item)); 39755d4f98a2SYan Zheng btrfs_set_inode_generation(leaf, item, 1); 39760257bb82SYan, Zheng btrfs_set_inode_size(leaf, item, 0); 39775d4f98a2SYan Zheng btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); 39783fd0a558SYan, Zheng btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS | 39793fd0a558SYan, Zheng BTRFS_INODE_PREALLOC); 39805d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 39815d4f98a2SYan Zheng out: 39825d4f98a2SYan Zheng btrfs_free_path(path); 39835d4f98a2SYan Zheng return ret; 39845d4f98a2SYan Zheng } 39855d4f98a2SYan Zheng 39865d4f98a2SYan Zheng /* 39875d4f98a2SYan Zheng * helper to create inode for data relocation. 39885d4f98a2SYan Zheng * the inode is in data relocation tree and its link count is 0 39895d4f98a2SYan Zheng */ 39903fd0a558SYan, Zheng static noinline_for_stack 39913fd0a558SYan, Zheng struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, 399232da5386SDavid Sterba struct btrfs_block_group *group) 39935d4f98a2SYan Zheng { 39945d4f98a2SYan Zheng struct inode *inode = NULL; 39955d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 39965d4f98a2SYan Zheng struct btrfs_root *root; 39975d4f98a2SYan Zheng struct btrfs_key key; 39984624900dSZhaolei u64 objectid; 39995d4f98a2SYan Zheng int err = 0; 40005d4f98a2SYan Zheng 40015d4f98a2SYan Zheng root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 40025d4f98a2SYan Zheng if (IS_ERR(root)) 40035d4f98a2SYan Zheng return ERR_CAST(root); 40045d4f98a2SYan Zheng 4005a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 6); 400676deacf0SJosef Bacik if (IS_ERR(trans)) { 400700246528SJosef Bacik btrfs_put_root(root); 40083fd0a558SYan, Zheng return ERR_CAST(trans); 400976deacf0SJosef Bacik } 40105d4f98a2SYan Zheng 4011581bb050SLi Zefan err = btrfs_find_free_objectid(root, &objectid); 40125d4f98a2SYan Zheng if (err) 40135d4f98a2SYan Zheng goto out; 40145d4f98a2SYan Zheng 40150257bb82SYan, Zheng err = __insert_orphan_inode(trans, root, objectid); 40165d4f98a2SYan Zheng BUG_ON(err); 40175d4f98a2SYan Zheng 40185d4f98a2SYan Zheng key.objectid = objectid; 40195d4f98a2SYan Zheng key.type = BTRFS_INODE_ITEM_KEY; 40205d4f98a2SYan Zheng key.offset = 0; 40214c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 40222e19f1f9SAl Viro BUG_ON(IS_ERR(inode)); 4023b3470b5dSDavid Sterba BTRFS_I(inode)->index_cnt = group->start; 40245d4f98a2SYan Zheng 402573f2e545SNikolay Borisov err = btrfs_orphan_add(trans, BTRFS_I(inode)); 40265d4f98a2SYan Zheng out: 402700246528SJosef Bacik btrfs_put_root(root); 40283a45bb20SJeff Mahoney btrfs_end_transaction(trans); 40292ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 40305d4f98a2SYan Zheng if (err) { 40315d4f98a2SYan Zheng if (inode) 40325d4f98a2SYan Zheng iput(inode); 40335d4f98a2SYan Zheng inode = ERR_PTR(err); 40345d4f98a2SYan Zheng } 40355d4f98a2SYan Zheng return inode; 40365d4f98a2SYan Zheng } 40375d4f98a2SYan Zheng 4038c258d6e3SQu Wenruo static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info) 40393fd0a558SYan, Zheng { 40403fd0a558SYan, Zheng struct reloc_control *rc; 40413fd0a558SYan, Zheng 40423fd0a558SYan, Zheng rc = kzalloc(sizeof(*rc), GFP_NOFS); 40433fd0a558SYan, Zheng if (!rc) 40443fd0a558SYan, Zheng return NULL; 40453fd0a558SYan, Zheng 40463fd0a558SYan, Zheng INIT_LIST_HEAD(&rc->reloc_roots); 4047d2311e69SQu Wenruo INIT_LIST_HEAD(&rc->dirty_subvol_roots); 4048584fb121SQu Wenruo btrfs_backref_init_cache(fs_info, &rc->backref_cache, 1); 40493fd0a558SYan, Zheng mapping_tree_init(&rc->reloc_root_tree); 405043eb5f29SQu Wenruo extent_io_tree_init(fs_info, &rc->processed_blocks, 405143eb5f29SQu Wenruo IO_TREE_RELOC_BLOCKS, NULL); 40523fd0a558SYan, Zheng return rc; 40533fd0a558SYan, Zheng } 40543fd0a558SYan, Zheng 40551a0afa0eSJosef Bacik static void free_reloc_control(struct reloc_control *rc) 40561a0afa0eSJosef Bacik { 40571a0afa0eSJosef Bacik struct mapping_node *node, *tmp; 40581a0afa0eSJosef Bacik 40591a0afa0eSJosef Bacik free_reloc_roots(&rc->reloc_roots); 40601a0afa0eSJosef Bacik rbtree_postorder_for_each_entry_safe(node, tmp, 40611a0afa0eSJosef Bacik &rc->reloc_root_tree.rb_root, rb_node) 40621a0afa0eSJosef Bacik kfree(node); 40631a0afa0eSJosef Bacik 40641a0afa0eSJosef Bacik kfree(rc); 40651a0afa0eSJosef Bacik } 40661a0afa0eSJosef Bacik 40675d4f98a2SYan Zheng /* 4068ebce0e01SAdam Borowski * Print the block group being relocated 4069ebce0e01SAdam Borowski */ 4070ebce0e01SAdam Borowski static void describe_relocation(struct btrfs_fs_info *fs_info, 407132da5386SDavid Sterba struct btrfs_block_group *block_group) 4072ebce0e01SAdam Borowski { 4073f89e09cfSAnand Jain char buf[128] = {'\0'}; 4074ebce0e01SAdam Borowski 4075f89e09cfSAnand Jain btrfs_describe_block_groups(block_group->flags, buf, sizeof(buf)); 4076ebce0e01SAdam Borowski 4077ebce0e01SAdam Borowski btrfs_info(fs_info, 4078ebce0e01SAdam Borowski "relocating block group %llu flags %s", 4079b3470b5dSDavid Sterba block_group->start, buf); 4080ebce0e01SAdam Borowski } 4081ebce0e01SAdam Borowski 4082430640e3SQu Wenruo static const char *stage_to_string(int stage) 4083430640e3SQu Wenruo { 4084430640e3SQu Wenruo if (stage == MOVE_DATA_EXTENTS) 4085430640e3SQu Wenruo return "move data extents"; 4086430640e3SQu Wenruo if (stage == UPDATE_DATA_PTRS) 4087430640e3SQu Wenruo return "update data pointers"; 4088430640e3SQu Wenruo return "unknown"; 4089430640e3SQu Wenruo } 4090430640e3SQu Wenruo 4091ebce0e01SAdam Borowski /* 40925d4f98a2SYan Zheng * function to relocate all extents in a block group. 40935d4f98a2SYan Zheng */ 40946bccf3abSJeff Mahoney int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start) 40955d4f98a2SYan Zheng { 409632da5386SDavid Sterba struct btrfs_block_group *bg; 40976bccf3abSJeff Mahoney struct btrfs_root *extent_root = fs_info->extent_root; 40985d4f98a2SYan Zheng struct reloc_control *rc; 40990af3d00bSJosef Bacik struct inode *inode; 41000af3d00bSJosef Bacik struct btrfs_path *path; 41015d4f98a2SYan Zheng int ret; 4102f0486c68SYan, Zheng int rw = 0; 41035d4f98a2SYan Zheng int err = 0; 41045d4f98a2SYan Zheng 4105eede2bf3SOmar Sandoval bg = btrfs_lookup_block_group(fs_info, group_start); 4106eede2bf3SOmar Sandoval if (!bg) 4107eede2bf3SOmar Sandoval return -ENOENT; 4108eede2bf3SOmar Sandoval 4109eede2bf3SOmar Sandoval if (btrfs_pinned_by_swapfile(fs_info, bg)) { 4110eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 4111eede2bf3SOmar Sandoval return -ETXTBSY; 4112eede2bf3SOmar Sandoval } 4113eede2bf3SOmar Sandoval 4114c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 4115eede2bf3SOmar Sandoval if (!rc) { 4116eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 41175d4f98a2SYan Zheng return -ENOMEM; 4118eede2bf3SOmar Sandoval } 41195d4f98a2SYan Zheng 4120f0486c68SYan, Zheng rc->extent_root = extent_root; 4121eede2bf3SOmar Sandoval rc->block_group = bg; 41225d4f98a2SYan Zheng 4123b12de528SQu Wenruo ret = btrfs_inc_block_group_ro(rc->block_group, true); 4124f0486c68SYan, Zheng if (ret) { 4125f0486c68SYan, Zheng err = ret; 4126f0486c68SYan, Zheng goto out; 4127f0486c68SYan, Zheng } 4128f0486c68SYan, Zheng rw = 1; 4129f0486c68SYan, Zheng 41300af3d00bSJosef Bacik path = btrfs_alloc_path(); 41310af3d00bSJosef Bacik if (!path) { 41320af3d00bSJosef Bacik err = -ENOMEM; 41330af3d00bSJosef Bacik goto out; 41340af3d00bSJosef Bacik } 41350af3d00bSJosef Bacik 41367949f339SDavid Sterba inode = lookup_free_space_inode(rc->block_group, path); 41370af3d00bSJosef Bacik btrfs_free_path(path); 41380af3d00bSJosef Bacik 41390af3d00bSJosef Bacik if (!IS_ERR(inode)) 41401bbc621eSChris Mason ret = delete_block_group_cache(fs_info, rc->block_group, inode, 0); 41410af3d00bSJosef Bacik else 41420af3d00bSJosef Bacik ret = PTR_ERR(inode); 41430af3d00bSJosef Bacik 41440af3d00bSJosef Bacik if (ret && ret != -ENOENT) { 41450af3d00bSJosef Bacik err = ret; 41460af3d00bSJosef Bacik goto out; 41470af3d00bSJosef Bacik } 41480af3d00bSJosef Bacik 41495d4f98a2SYan Zheng rc->data_inode = create_reloc_inode(fs_info, rc->block_group); 41505d4f98a2SYan Zheng if (IS_ERR(rc->data_inode)) { 41515d4f98a2SYan Zheng err = PTR_ERR(rc->data_inode); 41525d4f98a2SYan Zheng rc->data_inode = NULL; 41535d4f98a2SYan Zheng goto out; 41545d4f98a2SYan Zheng } 41555d4f98a2SYan Zheng 41560b246afaSJeff Mahoney describe_relocation(fs_info, rc->block_group); 41575d4f98a2SYan Zheng 41589cfa3e34SFilipe Manana btrfs_wait_block_group_reservations(rc->block_group); 4159f78c436cSFilipe Manana btrfs_wait_nocow_writers(rc->block_group); 41606374e57aSChris Mason btrfs_wait_ordered_roots(fs_info, U64_MAX, 4161b3470b5dSDavid Sterba rc->block_group->start, 4162b3470b5dSDavid Sterba rc->block_group->length); 41635d4f98a2SYan Zheng 41645d4f98a2SYan Zheng while (1) { 4165430640e3SQu Wenruo int finishes_stage; 4166430640e3SQu Wenruo 416776dda93cSYan, Zheng mutex_lock(&fs_info->cleaner_mutex); 41685d4f98a2SYan Zheng ret = relocate_block_group(rc); 416976dda93cSYan, Zheng mutex_unlock(&fs_info->cleaner_mutex); 4170ff612ba7SJosef Bacik if (ret < 0) 41715d4f98a2SYan Zheng err = ret; 4172ff612ba7SJosef Bacik 4173430640e3SQu Wenruo finishes_stage = rc->stage; 4174ff612ba7SJosef Bacik /* 4175ff612ba7SJosef Bacik * We may have gotten ENOSPC after we already dirtied some 4176ff612ba7SJosef Bacik * extents. If writeout happens while we're relocating a 4177ff612ba7SJosef Bacik * different block group we could end up hitting the 4178ff612ba7SJosef Bacik * BUG_ON(rc->stage == UPDATE_DATA_PTRS) in 4179ff612ba7SJosef Bacik * btrfs_reloc_cow_block. Make sure we write everything out 4180ff612ba7SJosef Bacik * properly so we don't trip over this problem, and then break 4181ff612ba7SJosef Bacik * out of the loop if we hit an error. 4182ff612ba7SJosef Bacik */ 4183ff612ba7SJosef Bacik if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { 4184ff612ba7SJosef Bacik ret = btrfs_wait_ordered_range(rc->data_inode, 0, 4185ff612ba7SJosef Bacik (u64)-1); 4186ff612ba7SJosef Bacik if (ret) 4187ff612ba7SJosef Bacik err = ret; 4188ff612ba7SJosef Bacik invalidate_mapping_pages(rc->data_inode->i_mapping, 4189ff612ba7SJosef Bacik 0, -1); 4190ff612ba7SJosef Bacik rc->stage = UPDATE_DATA_PTRS; 41915d4f98a2SYan Zheng } 41925d4f98a2SYan Zheng 4193ff612ba7SJosef Bacik if (err < 0) 4194ff612ba7SJosef Bacik goto out; 4195ff612ba7SJosef Bacik 41965d4f98a2SYan Zheng if (rc->extents_found == 0) 41975d4f98a2SYan Zheng break; 41985d4f98a2SYan Zheng 4199430640e3SQu Wenruo btrfs_info(fs_info, "found %llu extents, stage: %s", 4200430640e3SQu Wenruo rc->extents_found, stage_to_string(finishes_stage)); 42015d4f98a2SYan Zheng } 42025d4f98a2SYan Zheng 42035d4f98a2SYan Zheng WARN_ON(rc->block_group->pinned > 0); 42045d4f98a2SYan Zheng WARN_ON(rc->block_group->reserved > 0); 4205bf38be65SDavid Sterba WARN_ON(rc->block_group->used > 0); 42065d4f98a2SYan Zheng out: 4207f0486c68SYan, Zheng if (err && rw) 42082ff7e61eSJeff Mahoney btrfs_dec_block_group_ro(rc->block_group); 42095d4f98a2SYan Zheng iput(rc->data_inode); 42105d4f98a2SYan Zheng btrfs_put_block_group(rc->block_group); 42111a0afa0eSJosef Bacik free_reloc_control(rc); 42125d4f98a2SYan Zheng return err; 42135d4f98a2SYan Zheng } 42145d4f98a2SYan Zheng 421576dda93cSYan, Zheng static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) 421676dda93cSYan, Zheng { 42170b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 421876dda93cSYan, Zheng struct btrfs_trans_handle *trans; 421979787eaaSJeff Mahoney int ret, err; 422076dda93cSYan, Zheng 42210b246afaSJeff Mahoney trans = btrfs_start_transaction(fs_info->tree_root, 0); 422279787eaaSJeff Mahoney if (IS_ERR(trans)) 422379787eaaSJeff Mahoney return PTR_ERR(trans); 422476dda93cSYan, Zheng 422576dda93cSYan, Zheng memset(&root->root_item.drop_progress, 0, 422676dda93cSYan, Zheng sizeof(root->root_item.drop_progress)); 422776dda93cSYan, Zheng root->root_item.drop_level = 0; 422876dda93cSYan, Zheng btrfs_set_root_refs(&root->root_item, 0); 42290b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 423076dda93cSYan, Zheng &root->root_key, &root->root_item); 423176dda93cSYan, Zheng 42323a45bb20SJeff Mahoney err = btrfs_end_transaction(trans); 423379787eaaSJeff Mahoney if (err) 423479787eaaSJeff Mahoney return err; 423579787eaaSJeff Mahoney return ret; 423676dda93cSYan, Zheng } 423776dda93cSYan, Zheng 42385d4f98a2SYan Zheng /* 42395d4f98a2SYan Zheng * recover relocation interrupted by system crash. 42405d4f98a2SYan Zheng * 42415d4f98a2SYan Zheng * this function resumes merging reloc trees with corresponding fs trees. 42425d4f98a2SYan Zheng * this is important for keeping the sharing of tree blocks 42435d4f98a2SYan Zheng */ 42445d4f98a2SYan Zheng int btrfs_recover_relocation(struct btrfs_root *root) 42455d4f98a2SYan Zheng { 42460b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 42475d4f98a2SYan Zheng LIST_HEAD(reloc_roots); 42485d4f98a2SYan Zheng struct btrfs_key key; 42495d4f98a2SYan Zheng struct btrfs_root *fs_root; 42505d4f98a2SYan Zheng struct btrfs_root *reloc_root; 42515d4f98a2SYan Zheng struct btrfs_path *path; 42525d4f98a2SYan Zheng struct extent_buffer *leaf; 42535d4f98a2SYan Zheng struct reloc_control *rc = NULL; 42545d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 42555d4f98a2SYan Zheng int ret; 42565d4f98a2SYan Zheng int err = 0; 42575d4f98a2SYan Zheng 42585d4f98a2SYan Zheng path = btrfs_alloc_path(); 42595d4f98a2SYan Zheng if (!path) 42605d4f98a2SYan Zheng return -ENOMEM; 4261e4058b54SDavid Sterba path->reada = READA_BACK; 42625d4f98a2SYan Zheng 42635d4f98a2SYan Zheng key.objectid = BTRFS_TREE_RELOC_OBJECTID; 42645d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 42655d4f98a2SYan Zheng key.offset = (u64)-1; 42665d4f98a2SYan Zheng 42675d4f98a2SYan Zheng while (1) { 42680b246afaSJeff Mahoney ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, 42695d4f98a2SYan Zheng path, 0, 0); 42705d4f98a2SYan Zheng if (ret < 0) { 42715d4f98a2SYan Zheng err = ret; 42725d4f98a2SYan Zheng goto out; 42735d4f98a2SYan Zheng } 42745d4f98a2SYan Zheng if (ret > 0) { 42755d4f98a2SYan Zheng if (path->slots[0] == 0) 42765d4f98a2SYan Zheng break; 42775d4f98a2SYan Zheng path->slots[0]--; 42785d4f98a2SYan Zheng } 42795d4f98a2SYan Zheng leaf = path->nodes[0]; 42805d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4281b3b4aa74SDavid Sterba btrfs_release_path(path); 42825d4f98a2SYan Zheng 42835d4f98a2SYan Zheng if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || 42845d4f98a2SYan Zheng key.type != BTRFS_ROOT_ITEM_KEY) 42855d4f98a2SYan Zheng break; 42865d4f98a2SYan Zheng 42873dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(root, &key); 42885d4f98a2SYan Zheng if (IS_ERR(reloc_root)) { 42895d4f98a2SYan Zheng err = PTR_ERR(reloc_root); 42905d4f98a2SYan Zheng goto out; 42915d4f98a2SYan Zheng } 42925d4f98a2SYan Zheng 42933dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 42945d4f98a2SYan Zheng list_add(&reloc_root->root_list, &reloc_roots); 42955d4f98a2SYan Zheng 42965d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 42970b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, 42985d4f98a2SYan Zheng reloc_root->root_key.offset); 42995d4f98a2SYan Zheng if (IS_ERR(fs_root)) { 430076dda93cSYan, Zheng ret = PTR_ERR(fs_root); 430176dda93cSYan, Zheng if (ret != -ENOENT) { 430276dda93cSYan, Zheng err = ret; 43035d4f98a2SYan Zheng goto out; 43045d4f98a2SYan Zheng } 430579787eaaSJeff Mahoney ret = mark_garbage_root(reloc_root); 430679787eaaSJeff Mahoney if (ret < 0) { 430779787eaaSJeff Mahoney err = ret; 430879787eaaSJeff Mahoney goto out; 430979787eaaSJeff Mahoney } 4310932fd26dSJosef Bacik } else { 431100246528SJosef Bacik btrfs_put_root(fs_root); 431276dda93cSYan, Zheng } 43135d4f98a2SYan Zheng } 43145d4f98a2SYan Zheng 43155d4f98a2SYan Zheng if (key.offset == 0) 43165d4f98a2SYan Zheng break; 43175d4f98a2SYan Zheng 43185d4f98a2SYan Zheng key.offset--; 43195d4f98a2SYan Zheng } 4320b3b4aa74SDavid Sterba btrfs_release_path(path); 43215d4f98a2SYan Zheng 43225d4f98a2SYan Zheng if (list_empty(&reloc_roots)) 43235d4f98a2SYan Zheng goto out; 43245d4f98a2SYan Zheng 4325c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 43265d4f98a2SYan Zheng if (!rc) { 43275d4f98a2SYan Zheng err = -ENOMEM; 43285d4f98a2SYan Zheng goto out; 43295d4f98a2SYan Zheng } 43305d4f98a2SYan Zheng 43310b246afaSJeff Mahoney rc->extent_root = fs_info->extent_root; 43325d4f98a2SYan Zheng 43335d4f98a2SYan Zheng set_reloc_control(rc); 43345d4f98a2SYan Zheng 43357a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 43363612b495STsutomu Itoh if (IS_ERR(trans)) { 43373612b495STsutomu Itoh err = PTR_ERR(trans); 4338fb2d83eeSJosef Bacik goto out_unset; 43393612b495STsutomu Itoh } 43403fd0a558SYan, Zheng 43413fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 43423fd0a558SYan, Zheng 43435d4f98a2SYan Zheng while (!list_empty(&reloc_roots)) { 43445d4f98a2SYan Zheng reloc_root = list_entry(reloc_roots.next, 43455d4f98a2SYan Zheng struct btrfs_root, root_list); 43465d4f98a2SYan Zheng list_del(&reloc_root->root_list); 43475d4f98a2SYan Zheng 43485d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) == 0) { 43495d4f98a2SYan Zheng list_add_tail(&reloc_root->root_list, 43505d4f98a2SYan Zheng &rc->reloc_roots); 43515d4f98a2SYan Zheng continue; 43525d4f98a2SYan Zheng } 43535d4f98a2SYan Zheng 43540b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, reloc_root->root_key.offset); 435579787eaaSJeff Mahoney if (IS_ERR(fs_root)) { 435679787eaaSJeff Mahoney err = PTR_ERR(fs_root); 4357ca1aa281SJosef Bacik list_add_tail(&reloc_root->root_list, &reloc_roots); 43581402d17dSXiyu Yang btrfs_end_transaction(trans); 4359fb2d83eeSJosef Bacik goto out_unset; 436079787eaaSJeff Mahoney } 43615d4f98a2SYan Zheng 4362ffd7b339SJeff Mahoney err = __add_reloc_root(reloc_root); 436379787eaaSJeff Mahoney BUG_ON(err < 0); /* -ENOMEM or logic error */ 4364f44deb74SJosef Bacik fs_root->reloc_root = btrfs_grab_root(reloc_root); 436500246528SJosef Bacik btrfs_put_root(fs_root); 43665d4f98a2SYan Zheng } 43675d4f98a2SYan Zheng 43683a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 436979787eaaSJeff Mahoney if (err) 4370fb2d83eeSJosef Bacik goto out_unset; 43715d4f98a2SYan Zheng 43725d4f98a2SYan Zheng merge_reloc_roots(rc); 43735d4f98a2SYan Zheng 43745d4f98a2SYan Zheng unset_reloc_control(rc); 43755d4f98a2SYan Zheng 43767a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 437762b99540SQu Wenruo if (IS_ERR(trans)) { 43783612b495STsutomu Itoh err = PTR_ERR(trans); 43796217b0faSJosef Bacik goto out_clean; 438062b99540SQu Wenruo } 43813a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 43826217b0faSJosef Bacik out_clean: 4383d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 4384d2311e69SQu Wenruo if (ret < 0 && !err) 4385d2311e69SQu Wenruo err = ret; 4386fb2d83eeSJosef Bacik out_unset: 4387fb2d83eeSJosef Bacik unset_reloc_control(rc); 43881a0afa0eSJosef Bacik free_reloc_control(rc); 43893612b495STsutomu Itoh out: 4390aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 4391aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 4392aca1bba6SLiu Bo 43935d4f98a2SYan Zheng btrfs_free_path(path); 43945d4f98a2SYan Zheng 43955d4f98a2SYan Zheng if (err == 0) { 43965d4f98a2SYan Zheng /* cleanup orphan inode in data relocation tree */ 43970b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 4398932fd26dSJosef Bacik if (IS_ERR(fs_root)) { 43995d4f98a2SYan Zheng err = PTR_ERR(fs_root); 4400932fd26dSJosef Bacik } else { 440166b4ffd1SJosef Bacik err = btrfs_orphan_cleanup(fs_root); 440200246528SJosef Bacik btrfs_put_root(fs_root); 4403932fd26dSJosef Bacik } 4404932fd26dSJosef Bacik } 44055d4f98a2SYan Zheng return err; 44065d4f98a2SYan Zheng } 44075d4f98a2SYan Zheng 44085d4f98a2SYan Zheng /* 44095d4f98a2SYan Zheng * helper to add ordered checksum for data relocation. 44105d4f98a2SYan Zheng * 44115d4f98a2SYan Zheng * cloning checksum properly handles the nodatasum extents. 44125d4f98a2SYan Zheng * it also saves CPU time to re-calculate the checksum. 44135d4f98a2SYan Zheng */ 44145d4f98a2SYan Zheng int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) 44155d4f98a2SYan Zheng { 44160b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 44175d4f98a2SYan Zheng struct btrfs_ordered_sum *sums; 44185d4f98a2SYan Zheng struct btrfs_ordered_extent *ordered; 44195d4f98a2SYan Zheng int ret; 44205d4f98a2SYan Zheng u64 disk_bytenr; 44214577b014SJosef Bacik u64 new_bytenr; 44225d4f98a2SYan Zheng LIST_HEAD(list); 44235d4f98a2SYan Zheng 44245d4f98a2SYan Zheng ordered = btrfs_lookup_ordered_extent(inode, file_pos); 4425bffe633eSOmar Sandoval BUG_ON(ordered->file_offset != file_pos || ordered->num_bytes != len); 44265d4f98a2SYan Zheng 44275d4f98a2SYan Zheng disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; 44280b246afaSJeff Mahoney ret = btrfs_lookup_csums_range(fs_info->csum_root, disk_bytenr, 4429a2de733cSArne Jansen disk_bytenr + len - 1, &list, 0); 443079787eaaSJeff Mahoney if (ret) 443179787eaaSJeff Mahoney goto out; 44325d4f98a2SYan Zheng 44335d4f98a2SYan Zheng while (!list_empty(&list)) { 44345d4f98a2SYan Zheng sums = list_entry(list.next, struct btrfs_ordered_sum, list); 44355d4f98a2SYan Zheng list_del_init(&sums->list); 44365d4f98a2SYan Zheng 44374577b014SJosef Bacik /* 44384577b014SJosef Bacik * We need to offset the new_bytenr based on where the csum is. 44394577b014SJosef Bacik * We need to do this because we will read in entire prealloc 44404577b014SJosef Bacik * extents but we may have written to say the middle of the 44414577b014SJosef Bacik * prealloc extent, so we need to make sure the csum goes with 44424577b014SJosef Bacik * the right disk offset. 44434577b014SJosef Bacik * 44444577b014SJosef Bacik * We can do this because the data reloc inode refers strictly 44454577b014SJosef Bacik * to the on disk bytes, so we don't have to worry about 44464577b014SJosef Bacik * disk_len vs real len like with real inodes since it's all 44474577b014SJosef Bacik * disk length. 44484577b014SJosef Bacik */ 4449bffe633eSOmar Sandoval new_bytenr = ordered->disk_bytenr + sums->bytenr - disk_bytenr; 44504577b014SJosef Bacik sums->bytenr = new_bytenr; 44515d4f98a2SYan Zheng 4452f9756261SNikolay Borisov btrfs_add_ordered_sum(ordered, sums); 44535d4f98a2SYan Zheng } 445479787eaaSJeff Mahoney out: 44555d4f98a2SYan Zheng btrfs_put_ordered_extent(ordered); 4456411fc6bcSAndi Kleen return ret; 44575d4f98a2SYan Zheng } 44583fd0a558SYan, Zheng 445983d4cfd4SJosef Bacik int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, 44603fd0a558SYan, Zheng struct btrfs_root *root, struct extent_buffer *buf, 44613fd0a558SYan, Zheng struct extent_buffer *cow) 44623fd0a558SYan, Zheng { 44630b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 44643fd0a558SYan, Zheng struct reloc_control *rc; 4465a26195a5SQu Wenruo struct btrfs_backref_node *node; 44663fd0a558SYan, Zheng int first_cow = 0; 44673fd0a558SYan, Zheng int level; 446883d4cfd4SJosef Bacik int ret = 0; 44693fd0a558SYan, Zheng 44700b246afaSJeff Mahoney rc = fs_info->reloc_ctl; 44713fd0a558SYan, Zheng if (!rc) 447283d4cfd4SJosef Bacik return 0; 44733fd0a558SYan, Zheng 44743fd0a558SYan, Zheng BUG_ON(rc->stage == UPDATE_DATA_PTRS && 44753fd0a558SYan, Zheng root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID); 44763fd0a558SYan, Zheng 44773fd0a558SYan, Zheng level = btrfs_header_level(buf); 44783fd0a558SYan, Zheng if (btrfs_header_generation(buf) <= 44793fd0a558SYan, Zheng btrfs_root_last_snapshot(&root->root_item)) 44803fd0a558SYan, Zheng first_cow = 1; 44813fd0a558SYan, Zheng 44823fd0a558SYan, Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID && 44833fd0a558SYan, Zheng rc->create_reloc_tree) { 44843fd0a558SYan, Zheng WARN_ON(!first_cow && level == 0); 44853fd0a558SYan, Zheng 44863fd0a558SYan, Zheng node = rc->backref_cache.path[level]; 44873fd0a558SYan, Zheng BUG_ON(node->bytenr != buf->start && 44883fd0a558SYan, Zheng node->new_bytenr != buf->start); 44893fd0a558SYan, Zheng 4490b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(node); 449167439dadSDavid Sterba atomic_inc(&cow->refs); 44923fd0a558SYan, Zheng node->eb = cow; 44933fd0a558SYan, Zheng node->new_bytenr = cow->start; 44943fd0a558SYan, Zheng 44953fd0a558SYan, Zheng if (!node->pending) { 44963fd0a558SYan, Zheng list_move_tail(&node->list, 44973fd0a558SYan, Zheng &rc->backref_cache.pending[level]); 44983fd0a558SYan, Zheng node->pending = 1; 44993fd0a558SYan, Zheng } 45003fd0a558SYan, Zheng 45013fd0a558SYan, Zheng if (first_cow) 45029569cc20SQu Wenruo mark_block_processed(rc, node); 45033fd0a558SYan, Zheng 45043fd0a558SYan, Zheng if (first_cow && level > 0) 45053fd0a558SYan, Zheng rc->nodes_relocated += buf->len; 45063fd0a558SYan, Zheng } 45073fd0a558SYan, Zheng 450883d4cfd4SJosef Bacik if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) 45093fd0a558SYan, Zheng ret = replace_file_extents(trans, rc, root, cow); 451083d4cfd4SJosef Bacik return ret; 45113fd0a558SYan, Zheng } 45123fd0a558SYan, Zheng 45133fd0a558SYan, Zheng /* 45143fd0a558SYan, Zheng * called before creating snapshot. it calculates metadata reservation 451501327610SNicholas D Steeves * required for relocating tree blocks in the snapshot 45163fd0a558SYan, Zheng */ 4517147d256eSZhaolei void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending, 45183fd0a558SYan, Zheng u64 *bytes_to_reserve) 45193fd0a558SYan, Zheng { 452010995c04SQu Wenruo struct btrfs_root *root = pending->root; 452110995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 45223fd0a558SYan, Zheng 45236282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 45243fd0a558SYan, Zheng return; 45253fd0a558SYan, Zheng 45263fd0a558SYan, Zheng if (!rc->merge_reloc_tree) 45273fd0a558SYan, Zheng return; 45283fd0a558SYan, Zheng 45293fd0a558SYan, Zheng root = root->reloc_root; 45303fd0a558SYan, Zheng BUG_ON(btrfs_root_refs(&root->root_item) == 0); 45313fd0a558SYan, Zheng /* 45323fd0a558SYan, Zheng * relocation is in the stage of merging trees. the space 45333fd0a558SYan, Zheng * used by merging a reloc tree is twice the size of 45343fd0a558SYan, Zheng * relocated tree nodes in the worst case. half for cowing 45353fd0a558SYan, Zheng * the reloc tree, half for cowing the fs tree. the space 45363fd0a558SYan, Zheng * used by cowing the reloc tree will be freed after the 45373fd0a558SYan, Zheng * tree is dropped. if we create snapshot, cowing the fs 45383fd0a558SYan, Zheng * tree may use more space than it frees. so we need 45393fd0a558SYan, Zheng * reserve extra space. 45403fd0a558SYan, Zheng */ 45413fd0a558SYan, Zheng *bytes_to_reserve += rc->nodes_relocated; 45423fd0a558SYan, Zheng } 45433fd0a558SYan, Zheng 45443fd0a558SYan, Zheng /* 45453fd0a558SYan, Zheng * called after snapshot is created. migrate block reservation 45463fd0a558SYan, Zheng * and create reloc root for the newly created snapshot 4547f44deb74SJosef Bacik * 4548f44deb74SJosef Bacik * This is similar to btrfs_init_reloc_root(), we come out of here with two 4549f44deb74SJosef Bacik * references held on the reloc_root, one for root->reloc_root and one for 4550f44deb74SJosef Bacik * rc->reloc_roots. 45513fd0a558SYan, Zheng */ 455249b25e05SJeff Mahoney int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, 45533fd0a558SYan, Zheng struct btrfs_pending_snapshot *pending) 45543fd0a558SYan, Zheng { 45553fd0a558SYan, Zheng struct btrfs_root *root = pending->root; 45563fd0a558SYan, Zheng struct btrfs_root *reloc_root; 45573fd0a558SYan, Zheng struct btrfs_root *new_root; 455810995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 45593fd0a558SYan, Zheng int ret; 45603fd0a558SYan, Zheng 45616282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 456249b25e05SJeff Mahoney return 0; 45633fd0a558SYan, Zheng 45643fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 45653fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated; 45663fd0a558SYan, Zheng 45673fd0a558SYan, Zheng if (rc->merge_reloc_tree) { 45683fd0a558SYan, Zheng ret = btrfs_block_rsv_migrate(&pending->block_rsv, 45693fd0a558SYan, Zheng rc->block_rsv, 45703a584174SLu Fengqi rc->nodes_relocated, true); 457149b25e05SJeff Mahoney if (ret) 457249b25e05SJeff Mahoney return ret; 45733fd0a558SYan, Zheng } 45743fd0a558SYan, Zheng 45753fd0a558SYan, Zheng new_root = pending->snap; 45763fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root->reloc_root, 45773fd0a558SYan, Zheng new_root->root_key.objectid); 457849b25e05SJeff Mahoney if (IS_ERR(reloc_root)) 457949b25e05SJeff Mahoney return PTR_ERR(reloc_root); 45803fd0a558SYan, Zheng 4581ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 4582ffd7b339SJeff Mahoney BUG_ON(ret < 0); 4583f44deb74SJosef Bacik new_root->reloc_root = btrfs_grab_root(reloc_root); 45843fd0a558SYan, Zheng 458549b25e05SJeff Mahoney if (rc->create_reloc_tree) 45863fd0a558SYan, Zheng ret = clone_backref_node(trans, rc, root, reloc_root); 458749b25e05SJeff Mahoney return ret; 45883fd0a558SYan, Zheng } 4589