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 178a26195a5SQu Wenruo static void backref_cache_cleanup(struct btrfs_backref_cache *cache) 1795d4f98a2SYan Zheng { 180a26195a5SQu Wenruo struct btrfs_backref_node *node; 1813fd0a558SYan, Zheng int i; 1823fd0a558SYan, Zheng 1833fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 1843fd0a558SYan, Zheng node = list_entry(cache->detached.next, 185a26195a5SQu Wenruo struct btrfs_backref_node, list); 186023acb07SQu Wenruo btrfs_backref_cleanup_node(cache, node); 1873fd0a558SYan, Zheng } 1883fd0a558SYan, Zheng 1893fd0a558SYan, Zheng while (!list_empty(&cache->leaves)) { 1903fd0a558SYan, Zheng node = list_entry(cache->leaves.next, 191a26195a5SQu Wenruo struct btrfs_backref_node, lower); 192023acb07SQu Wenruo btrfs_backref_cleanup_node(cache, node); 1933fd0a558SYan, Zheng } 1943fd0a558SYan, Zheng 1953fd0a558SYan, Zheng cache->last_trans = 0; 1963fd0a558SYan, Zheng 1973fd0a558SYan, Zheng for (i = 0; i < BTRFS_MAX_LEVEL; i++) 198f4907095SLiu Bo ASSERT(list_empty(&cache->pending[i])); 19984780289SQu Wenruo ASSERT(list_empty(&cache->pending_edge)); 20084780289SQu Wenruo ASSERT(list_empty(&cache->useless_node)); 201f4907095SLiu Bo ASSERT(list_empty(&cache->changed)); 202f4907095SLiu Bo ASSERT(list_empty(&cache->detached)); 203f4907095SLiu Bo ASSERT(RB_EMPTY_ROOT(&cache->rb_root)); 204f4907095SLiu Bo ASSERT(!cache->nr_nodes); 205f4907095SLiu Bo ASSERT(!cache->nr_edges); 2063fd0a558SYan, Zheng } 2073fd0a558SYan, Zheng 20848a3b636SEric Sandeen static void backref_tree_panic(struct rb_node *rb_node, int errno, u64 bytenr) 20943c04fb1SJeff Mahoney { 21043c04fb1SJeff Mahoney 21143c04fb1SJeff Mahoney struct btrfs_fs_info *fs_info = NULL; 212a26195a5SQu Wenruo struct btrfs_backref_node *bnode = rb_entry(rb_node, 213a26195a5SQu Wenruo struct btrfs_backref_node, rb_node); 21443c04fb1SJeff Mahoney if (bnode->root) 21543c04fb1SJeff Mahoney fs_info = bnode->root->fs_info; 2165d163e0eSJeff Mahoney btrfs_panic(fs_info, errno, 2175d163e0eSJeff Mahoney "Inconsistency in backref cache found at offset %llu", 2185d163e0eSJeff Mahoney bytenr); 21943c04fb1SJeff Mahoney } 22043c04fb1SJeff Mahoney 2215d4f98a2SYan Zheng /* 2225d4f98a2SYan Zheng * walk up backref nodes until reach node presents tree root 2235d4f98a2SYan Zheng */ 224a26195a5SQu Wenruo static struct btrfs_backref_node *walk_up_backref( 225a26195a5SQu Wenruo struct btrfs_backref_node *node, 226a26195a5SQu Wenruo struct btrfs_backref_edge *edges[], int *index) 2275d4f98a2SYan Zheng { 228a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2295d4f98a2SYan Zheng int idx = *index; 2305d4f98a2SYan Zheng 2315d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 2325d4f98a2SYan Zheng edge = list_entry(node->upper.next, 233a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 2345d4f98a2SYan Zheng edges[idx++] = edge; 2355d4f98a2SYan Zheng node = edge->node[UPPER]; 2365d4f98a2SYan Zheng } 2373fd0a558SYan, Zheng BUG_ON(node->detached); 2385d4f98a2SYan Zheng *index = idx; 2395d4f98a2SYan Zheng return node; 2405d4f98a2SYan Zheng } 2415d4f98a2SYan Zheng 2425d4f98a2SYan Zheng /* 2435d4f98a2SYan Zheng * walk down backref nodes to find start of next reference path 2445d4f98a2SYan Zheng */ 245a26195a5SQu Wenruo static struct btrfs_backref_node *walk_down_backref( 246a26195a5SQu Wenruo struct btrfs_backref_edge *edges[], int *index) 2475d4f98a2SYan Zheng { 248a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 249a26195a5SQu Wenruo struct btrfs_backref_node *lower; 2505d4f98a2SYan Zheng int idx = *index; 2515d4f98a2SYan Zheng 2525d4f98a2SYan Zheng while (idx > 0) { 2535d4f98a2SYan Zheng edge = edges[idx - 1]; 2545d4f98a2SYan Zheng lower = edge->node[LOWER]; 2555d4f98a2SYan Zheng if (list_is_last(&edge->list[LOWER], &lower->upper)) { 2565d4f98a2SYan Zheng idx--; 2575d4f98a2SYan Zheng continue; 2585d4f98a2SYan Zheng } 2595d4f98a2SYan Zheng edge = list_entry(edge->list[LOWER].next, 260a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 2615d4f98a2SYan Zheng edges[idx - 1] = edge; 2625d4f98a2SYan Zheng *index = idx; 2635d4f98a2SYan Zheng return edge->node[UPPER]; 2645d4f98a2SYan Zheng } 2655d4f98a2SYan Zheng *index = 0; 2665d4f98a2SYan Zheng return NULL; 2675d4f98a2SYan Zheng } 2685d4f98a2SYan Zheng 269a26195a5SQu Wenruo static void update_backref_node(struct btrfs_backref_cache *cache, 270a26195a5SQu Wenruo struct btrfs_backref_node *node, u64 bytenr) 2713fd0a558SYan, Zheng { 2723fd0a558SYan, Zheng struct rb_node *rb_node; 2733fd0a558SYan, Zheng rb_erase(&node->rb_node, &cache->rb_root); 2743fd0a558SYan, Zheng node->bytenr = bytenr; 275e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, node->bytenr, &node->rb_node); 27643c04fb1SJeff Mahoney if (rb_node) 27743c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, bytenr); 2783fd0a558SYan, Zheng } 2793fd0a558SYan, Zheng 2803fd0a558SYan, Zheng /* 2813fd0a558SYan, Zheng * update backref cache after a transaction commit 2823fd0a558SYan, Zheng */ 2833fd0a558SYan, Zheng static int update_backref_cache(struct btrfs_trans_handle *trans, 284a26195a5SQu Wenruo struct btrfs_backref_cache *cache) 2853fd0a558SYan, Zheng { 286a26195a5SQu Wenruo struct btrfs_backref_node *node; 2873fd0a558SYan, Zheng int level = 0; 2883fd0a558SYan, Zheng 2893fd0a558SYan, Zheng if (cache->last_trans == 0) { 2903fd0a558SYan, Zheng cache->last_trans = trans->transid; 2913fd0a558SYan, Zheng return 0; 2923fd0a558SYan, Zheng } 2933fd0a558SYan, Zheng 2943fd0a558SYan, Zheng if (cache->last_trans == trans->transid) 2953fd0a558SYan, Zheng return 0; 2963fd0a558SYan, Zheng 2973fd0a558SYan, Zheng /* 2983fd0a558SYan, Zheng * detached nodes are used to avoid unnecessary backref 2993fd0a558SYan, Zheng * lookup. transaction commit changes the extent tree. 3003fd0a558SYan, Zheng * so the detached nodes are no longer useful. 3013fd0a558SYan, Zheng */ 3023fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 3033fd0a558SYan, Zheng node = list_entry(cache->detached.next, 304a26195a5SQu Wenruo struct btrfs_backref_node, list); 305023acb07SQu Wenruo btrfs_backref_cleanup_node(cache, node); 3063fd0a558SYan, Zheng } 3073fd0a558SYan, Zheng 3083fd0a558SYan, Zheng while (!list_empty(&cache->changed)) { 3093fd0a558SYan, Zheng node = list_entry(cache->changed.next, 310a26195a5SQu Wenruo struct btrfs_backref_node, list); 3113fd0a558SYan, Zheng list_del_init(&node->list); 3123fd0a558SYan, Zheng BUG_ON(node->pending); 3133fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 3143fd0a558SYan, Zheng } 3153fd0a558SYan, Zheng 3163fd0a558SYan, Zheng /* 3173fd0a558SYan, Zheng * some nodes can be left in the pending list if there were 3183fd0a558SYan, Zheng * errors during processing the pending nodes. 3193fd0a558SYan, Zheng */ 3203fd0a558SYan, Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 3213fd0a558SYan, Zheng list_for_each_entry(node, &cache->pending[level], list) { 3223fd0a558SYan, Zheng BUG_ON(!node->pending); 3233fd0a558SYan, Zheng if (node->bytenr == node->new_bytenr) 3243fd0a558SYan, Zheng continue; 3253fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 3263fd0a558SYan, Zheng } 3273fd0a558SYan, Zheng } 3283fd0a558SYan, Zheng 3293fd0a558SYan, Zheng cache->last_trans = 0; 3303fd0a558SYan, Zheng return 1; 3313fd0a558SYan, Zheng } 3323fd0a558SYan, Zheng 3336282675eSQu Wenruo static bool reloc_root_is_dead(struct btrfs_root *root) 3346282675eSQu Wenruo { 3356282675eSQu Wenruo /* 3366282675eSQu Wenruo * Pair with set_bit/clear_bit in clean_dirty_subvols and 3376282675eSQu Wenruo * btrfs_update_reloc_root. We need to see the updated bit before 3386282675eSQu Wenruo * trying to access reloc_root 3396282675eSQu Wenruo */ 3406282675eSQu Wenruo smp_rmb(); 3416282675eSQu Wenruo if (test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state)) 3426282675eSQu Wenruo return true; 3436282675eSQu Wenruo return false; 3446282675eSQu Wenruo } 3456282675eSQu Wenruo 3466282675eSQu Wenruo /* 3476282675eSQu Wenruo * Check if this subvolume tree has valid reloc tree. 3486282675eSQu Wenruo * 3496282675eSQu Wenruo * Reloc tree after swap is considered dead, thus not considered as valid. 3506282675eSQu Wenruo * This is enough for most callers, as they don't distinguish dead reloc root 3516282675eSQu Wenruo * from no reloc root. But should_ignore_root() below is a special case. 3526282675eSQu Wenruo */ 3536282675eSQu Wenruo static bool have_reloc_root(struct btrfs_root *root) 3546282675eSQu Wenruo { 3556282675eSQu Wenruo if (reloc_root_is_dead(root)) 3566282675eSQu Wenruo return false; 3576282675eSQu Wenruo if (!root->reloc_root) 3586282675eSQu Wenruo return false; 3596282675eSQu Wenruo return true; 3606282675eSQu Wenruo } 361f2a97a9dSDavid Sterba 3623fd0a558SYan, Zheng static int should_ignore_root(struct btrfs_root *root) 3633fd0a558SYan, Zheng { 3643fd0a558SYan, Zheng struct btrfs_root *reloc_root; 3653fd0a558SYan, Zheng 36627cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 3673fd0a558SYan, Zheng return 0; 3683fd0a558SYan, Zheng 3696282675eSQu Wenruo /* This root has been merged with its reloc tree, we can ignore it */ 3706282675eSQu Wenruo if (reloc_root_is_dead(root)) 3716282675eSQu Wenruo return 1; 3726282675eSQu Wenruo 3733fd0a558SYan, Zheng reloc_root = root->reloc_root; 3743fd0a558SYan, Zheng if (!reloc_root) 3753fd0a558SYan, Zheng return 0; 3763fd0a558SYan, Zheng 3774d4225fcSJosef Bacik if (btrfs_header_generation(reloc_root->commit_root) == 3784d4225fcSJosef Bacik root->fs_info->running_transaction->transid) 3793fd0a558SYan, Zheng return 0; 3803fd0a558SYan, Zheng /* 3813fd0a558SYan, Zheng * if there is reloc tree and it was created in previous 3823fd0a558SYan, Zheng * transaction backref lookup can find the reloc tree, 3833fd0a558SYan, Zheng * so backref node for the fs tree root is useless for 3843fd0a558SYan, Zheng * relocation. 3853fd0a558SYan, Zheng */ 3863fd0a558SYan, Zheng return 1; 3873fd0a558SYan, Zheng } 3885d4f98a2SYan Zheng /* 3895d4f98a2SYan Zheng * find reloc tree by address of tree root 3905d4f98a2SYan Zheng */ 3912433bea5SQu Wenruo struct btrfs_root *find_reloc_root(struct btrfs_fs_info *fs_info, u64 bytenr) 3925d4f98a2SYan Zheng { 3932433bea5SQu Wenruo struct reloc_control *rc = fs_info->reloc_ctl; 3945d4f98a2SYan Zheng struct rb_node *rb_node; 3955d4f98a2SYan Zheng struct mapping_node *node; 3965d4f98a2SYan Zheng struct btrfs_root *root = NULL; 3975d4f98a2SYan Zheng 3982433bea5SQu Wenruo ASSERT(rc); 3995d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 400e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, bytenr); 4015d4f98a2SYan Zheng if (rb_node) { 4025d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 4035d4f98a2SYan Zheng root = (struct btrfs_root *)node->data; 4045d4f98a2SYan Zheng } 4055d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 40600246528SJosef Bacik return btrfs_grab_root(root); 4075d4f98a2SYan Zheng } 4085d4f98a2SYan Zheng 4095d4f98a2SYan Zheng static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, 4105d4f98a2SYan Zheng u64 root_objectid) 4115d4f98a2SYan Zheng { 4125d4f98a2SYan Zheng struct btrfs_key key; 4135d4f98a2SYan Zheng 4145d4f98a2SYan Zheng key.objectid = root_objectid; 4155d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 4165d4f98a2SYan Zheng key.offset = (u64)-1; 4175d4f98a2SYan Zheng 418bc44d7c4SJosef Bacik return btrfs_get_fs_root(fs_info, &key, false); 4195d4f98a2SYan Zheng } 4205d4f98a2SYan Zheng 4215d4f98a2SYan Zheng /* 4224007ea87SQu Wenruo * Handle direct tree backref 4234007ea87SQu Wenruo * 4244007ea87SQu Wenruo * Direct tree backref means, the backref item shows its parent bytenr 4254007ea87SQu Wenruo * directly. This is for SHARED_BLOCK_REF backref (keyed or inlined). 4264007ea87SQu Wenruo * 4274007ea87SQu Wenruo * @ref_key: The converted backref key. 4284007ea87SQu Wenruo * For keyed backref, it's the item key. 4294007ea87SQu Wenruo * For inlined backref, objectid is the bytenr, 4304007ea87SQu Wenruo * type is btrfs_inline_ref_type, offset is 4314007ea87SQu Wenruo * btrfs_inline_ref_offset. 4324007ea87SQu Wenruo */ 433a26195a5SQu Wenruo static int handle_direct_tree_backref(struct btrfs_backref_cache *cache, 4344007ea87SQu Wenruo struct btrfs_key *ref_key, 435a26195a5SQu Wenruo struct btrfs_backref_node *cur) 4364007ea87SQu Wenruo { 437a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 438a26195a5SQu Wenruo struct btrfs_backref_node *upper; 4394007ea87SQu Wenruo struct rb_node *rb_node; 4404007ea87SQu Wenruo 4414007ea87SQu Wenruo ASSERT(ref_key->type == BTRFS_SHARED_BLOCK_REF_KEY); 4424007ea87SQu Wenruo 4434007ea87SQu Wenruo /* Only reloc root uses backref pointing to itself */ 4444007ea87SQu Wenruo if (ref_key->objectid == ref_key->offset) { 4454007ea87SQu Wenruo struct btrfs_root *root; 4464007ea87SQu Wenruo 4474007ea87SQu Wenruo cur->is_reloc_root = 1; 4484007ea87SQu Wenruo /* Only reloc backref cache cares about a specific root */ 4494007ea87SQu Wenruo if (cache->is_reloc) { 4504007ea87SQu Wenruo root = find_reloc_root(cache->fs_info, cur->bytenr); 4514007ea87SQu Wenruo if (WARN_ON(!root)) 4524007ea87SQu Wenruo return -ENOENT; 4534007ea87SQu Wenruo cur->root = root; 4544007ea87SQu Wenruo } else { 4554007ea87SQu Wenruo /* 4564007ea87SQu Wenruo * For generic purpose backref cache, reloc root node 4574007ea87SQu Wenruo * is useless. 4584007ea87SQu Wenruo */ 4594007ea87SQu Wenruo list_add(&cur->list, &cache->useless_node); 4604007ea87SQu Wenruo } 4614007ea87SQu Wenruo return 0; 4624007ea87SQu Wenruo } 4634007ea87SQu Wenruo 46447254d07SQu Wenruo edge = btrfs_backref_alloc_edge(cache); 4654007ea87SQu Wenruo if (!edge) 4664007ea87SQu Wenruo return -ENOMEM; 4674007ea87SQu Wenruo 468e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, ref_key->offset); 4694007ea87SQu Wenruo if (!rb_node) { 4704007ea87SQu Wenruo /* Parent node not yet cached */ 471b1818dabSQu Wenruo upper = btrfs_backref_alloc_node(cache, ref_key->offset, 4720304f2d8SQu Wenruo cur->level + 1); 4734007ea87SQu Wenruo if (!upper) { 474741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 4754007ea87SQu Wenruo return -ENOMEM; 4764007ea87SQu Wenruo } 4774007ea87SQu Wenruo 4784007ea87SQu Wenruo /* 4794007ea87SQu Wenruo * Backrefs for the upper level block isn't cached, add the 4804007ea87SQu Wenruo * block to pending list 4814007ea87SQu Wenruo */ 4824007ea87SQu Wenruo list_add_tail(&edge->list[UPPER], &cache->pending_edge); 4834007ea87SQu Wenruo } else { 4844007ea87SQu Wenruo /* Parent node already cached */ 485a26195a5SQu Wenruo upper = rb_entry(rb_node, struct btrfs_backref_node, rb_node); 4864007ea87SQu Wenruo ASSERT(upper->checked); 4874007ea87SQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 4884007ea87SQu Wenruo } 489f39911e5SQu Wenruo btrfs_backref_link_edge(edge, cur, upper, LINK_LOWER); 4904007ea87SQu Wenruo return 0; 4914007ea87SQu Wenruo } 4924007ea87SQu Wenruo 4934007ea87SQu Wenruo /* 4944d81ea8bSQu Wenruo * Handle indirect tree backref 4954d81ea8bSQu Wenruo * 4964d81ea8bSQu Wenruo * Indirect tree backref means, we only know which tree the node belongs to. 4974d81ea8bSQu Wenruo * We still need to do a tree search to find out the parents. This is for 4984d81ea8bSQu Wenruo * TREE_BLOCK_REF backref (keyed or inlined). 4994d81ea8bSQu Wenruo * 5004d81ea8bSQu Wenruo * @ref_key: The same as @ref_key in handle_direct_tree_backref() 5014d81ea8bSQu Wenruo * @tree_key: The first key of this tree block. 5024d81ea8bSQu Wenruo * @path: A clean (released) path, to avoid allocating path everytime 5034d81ea8bSQu Wenruo * the function get called. 5044d81ea8bSQu Wenruo */ 505a26195a5SQu Wenruo static int handle_indirect_tree_backref(struct btrfs_backref_cache *cache, 5064d81ea8bSQu Wenruo struct btrfs_path *path, 5074d81ea8bSQu Wenruo struct btrfs_key *ref_key, 5084d81ea8bSQu Wenruo struct btrfs_key *tree_key, 509a26195a5SQu Wenruo struct btrfs_backref_node *cur) 5104d81ea8bSQu Wenruo { 5114d81ea8bSQu Wenruo struct btrfs_fs_info *fs_info = cache->fs_info; 512a26195a5SQu Wenruo struct btrfs_backref_node *upper; 513a26195a5SQu Wenruo struct btrfs_backref_node *lower; 514a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 5154d81ea8bSQu Wenruo struct extent_buffer *eb; 5164d81ea8bSQu Wenruo struct btrfs_root *root; 5174d81ea8bSQu Wenruo struct rb_node *rb_node; 5184d81ea8bSQu Wenruo int level; 5194d81ea8bSQu Wenruo bool need_check = true; 5204d81ea8bSQu Wenruo int ret; 5214d81ea8bSQu Wenruo 5224d81ea8bSQu Wenruo root = read_fs_root(fs_info, ref_key->offset); 5234d81ea8bSQu Wenruo if (IS_ERR(root)) 5244d81ea8bSQu Wenruo return PTR_ERR(root); 5254d81ea8bSQu Wenruo if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 5264d81ea8bSQu Wenruo cur->cowonly = 1; 5274d81ea8bSQu Wenruo 5284d81ea8bSQu Wenruo if (btrfs_root_level(&root->root_item) == cur->level) { 5294d81ea8bSQu Wenruo /* Tree root */ 5304d81ea8bSQu Wenruo ASSERT(btrfs_root_bytenr(&root->root_item) == cur->bytenr); 5314d81ea8bSQu Wenruo if (should_ignore_root(root)) { 5324d81ea8bSQu Wenruo btrfs_put_root(root); 5334d81ea8bSQu Wenruo list_add(&cur->list, &cache->useless_node); 5344d81ea8bSQu Wenruo } else { 5354d81ea8bSQu Wenruo cur->root = root; 5364d81ea8bSQu Wenruo } 5374d81ea8bSQu Wenruo return 0; 5384d81ea8bSQu Wenruo } 5394d81ea8bSQu Wenruo 5404d81ea8bSQu Wenruo level = cur->level + 1; 5414d81ea8bSQu Wenruo 5424d81ea8bSQu Wenruo /* Search the tree to find parent blocks referring to the block */ 5434d81ea8bSQu Wenruo path->search_commit_root = 1; 5444d81ea8bSQu Wenruo path->skip_locking = 1; 5454d81ea8bSQu Wenruo path->lowest_level = level; 5464d81ea8bSQu Wenruo ret = btrfs_search_slot(NULL, root, tree_key, path, 0, 0); 5474d81ea8bSQu Wenruo path->lowest_level = 0; 5484d81ea8bSQu Wenruo if (ret < 0) { 5494d81ea8bSQu Wenruo btrfs_put_root(root); 5504d81ea8bSQu Wenruo return ret; 5514d81ea8bSQu Wenruo } 5524d81ea8bSQu Wenruo if (ret > 0 && path->slots[level] > 0) 5534d81ea8bSQu Wenruo path->slots[level]--; 5544d81ea8bSQu Wenruo 5554d81ea8bSQu Wenruo eb = path->nodes[level]; 5564d81ea8bSQu Wenruo if (btrfs_node_blockptr(eb, path->slots[level]) != cur->bytenr) { 5574d81ea8bSQu Wenruo btrfs_err(fs_info, 5584d81ea8bSQu Wenruo "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)", 5594d81ea8bSQu Wenruo cur->bytenr, level - 1, root->root_key.objectid, 5604d81ea8bSQu Wenruo tree_key->objectid, tree_key->type, tree_key->offset); 5614d81ea8bSQu Wenruo btrfs_put_root(root); 5624d81ea8bSQu Wenruo ret = -ENOENT; 5634d81ea8bSQu Wenruo goto out; 5644d81ea8bSQu Wenruo } 5654d81ea8bSQu Wenruo lower = cur; 5664d81ea8bSQu Wenruo 5674d81ea8bSQu Wenruo /* Add all nodes and edges in the path */ 5684d81ea8bSQu Wenruo for (; level < BTRFS_MAX_LEVEL; level++) { 5694d81ea8bSQu Wenruo if (!path->nodes[level]) { 5704d81ea8bSQu Wenruo ASSERT(btrfs_root_bytenr(&root->root_item) == 5714d81ea8bSQu Wenruo lower->bytenr); 5724d81ea8bSQu Wenruo if (should_ignore_root(root)) { 5734d81ea8bSQu Wenruo btrfs_put_root(root); 5744d81ea8bSQu Wenruo list_add(&lower->list, &cache->useless_node); 5754d81ea8bSQu Wenruo } else { 5764d81ea8bSQu Wenruo lower->root = root; 5774d81ea8bSQu Wenruo } 5784d81ea8bSQu Wenruo break; 5794d81ea8bSQu Wenruo } 5804d81ea8bSQu Wenruo 58147254d07SQu Wenruo edge = btrfs_backref_alloc_edge(cache); 5824d81ea8bSQu Wenruo if (!edge) { 5834d81ea8bSQu Wenruo btrfs_put_root(root); 5844d81ea8bSQu Wenruo ret = -ENOMEM; 5854d81ea8bSQu Wenruo goto out; 5864d81ea8bSQu Wenruo } 5874d81ea8bSQu Wenruo 5884d81ea8bSQu Wenruo eb = path->nodes[level]; 589e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, eb->start); 5904d81ea8bSQu Wenruo if (!rb_node) { 591b1818dabSQu Wenruo upper = btrfs_backref_alloc_node(cache, eb->start, 5920304f2d8SQu Wenruo lower->level + 1); 5934d81ea8bSQu Wenruo if (!upper) { 5944d81ea8bSQu Wenruo btrfs_put_root(root); 595741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 5964d81ea8bSQu Wenruo ret = -ENOMEM; 5974d81ea8bSQu Wenruo goto out; 5984d81ea8bSQu Wenruo } 5994d81ea8bSQu Wenruo upper->owner = btrfs_header_owner(eb); 6004d81ea8bSQu Wenruo if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 6014d81ea8bSQu Wenruo upper->cowonly = 1; 6024d81ea8bSQu Wenruo 6034d81ea8bSQu Wenruo /* 6044d81ea8bSQu Wenruo * If we know the block isn't shared we can avoid 6054d81ea8bSQu Wenruo * checking its backrefs. 6064d81ea8bSQu Wenruo */ 6074d81ea8bSQu Wenruo if (btrfs_block_can_be_shared(root, eb)) 6084d81ea8bSQu Wenruo upper->checked = 0; 6094d81ea8bSQu Wenruo else 6104d81ea8bSQu Wenruo upper->checked = 1; 6114d81ea8bSQu Wenruo 6124d81ea8bSQu Wenruo /* 6134d81ea8bSQu Wenruo * Add the block to pending list if we need to check its 6144d81ea8bSQu Wenruo * backrefs, we only do this once while walking up a 6154d81ea8bSQu Wenruo * tree as we will catch anything else later on. 6164d81ea8bSQu Wenruo */ 6174d81ea8bSQu Wenruo if (!upper->checked && need_check) { 6184d81ea8bSQu Wenruo need_check = false; 6194d81ea8bSQu Wenruo list_add_tail(&edge->list[UPPER], 6204d81ea8bSQu Wenruo &cache->pending_edge); 6214d81ea8bSQu Wenruo } else { 6224d81ea8bSQu Wenruo if (upper->checked) 6234d81ea8bSQu Wenruo need_check = true; 6244d81ea8bSQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 6254d81ea8bSQu Wenruo } 6264d81ea8bSQu Wenruo } else { 627a26195a5SQu Wenruo upper = rb_entry(rb_node, struct btrfs_backref_node, 628a26195a5SQu Wenruo rb_node); 6294d81ea8bSQu Wenruo ASSERT(upper->checked); 6304d81ea8bSQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 6314d81ea8bSQu Wenruo if (!upper->owner) 6324d81ea8bSQu Wenruo upper->owner = btrfs_header_owner(eb); 6334d81ea8bSQu Wenruo } 634f39911e5SQu Wenruo btrfs_backref_link_edge(edge, lower, upper, LINK_LOWER); 6354d81ea8bSQu Wenruo 6364d81ea8bSQu Wenruo if (rb_node) { 6374d81ea8bSQu Wenruo btrfs_put_root(root); 6384d81ea8bSQu Wenruo break; 6394d81ea8bSQu Wenruo } 6404d81ea8bSQu Wenruo lower = upper; 6414d81ea8bSQu Wenruo upper = NULL; 6424d81ea8bSQu Wenruo } 6434d81ea8bSQu Wenruo out: 6444d81ea8bSQu Wenruo btrfs_release_path(path); 6454d81ea8bSQu Wenruo return ret; 6464d81ea8bSQu Wenruo } 6474d81ea8bSQu Wenruo 648a26195a5SQu Wenruo static int handle_one_tree_block(struct btrfs_backref_cache *cache, 649e7d571c7SQu Wenruo struct btrfs_path *path, 650e7d571c7SQu Wenruo struct btrfs_backref_iter *iter, 6515d4f98a2SYan Zheng struct btrfs_key *node_key, 652a26195a5SQu Wenruo struct btrfs_backref_node *cur) 6535d4f98a2SYan Zheng { 654e7d571c7SQu Wenruo struct btrfs_fs_info *fs_info = cache->fs_info; 655a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 656a26195a5SQu Wenruo struct btrfs_backref_node *exist; 6575d4f98a2SYan Zheng int ret; 6585d4f98a2SYan Zheng 65971f572a9SQu Wenruo ret = btrfs_backref_iter_start(iter, cur->bytenr); 660e7d571c7SQu Wenruo if (ret < 0) 661e7d571c7SQu Wenruo return ret; 66271f572a9SQu Wenruo /* 66371f572a9SQu Wenruo * We skip the first btrfs_tree_block_info, as we don't use the key 66471f572a9SQu Wenruo * stored in it, but fetch it from the tree block 66571f572a9SQu Wenruo */ 66671f572a9SQu Wenruo if (btrfs_backref_has_tree_block_info(iter)) { 66771f572a9SQu Wenruo ret = btrfs_backref_iter_next(iter); 668e7d571c7SQu Wenruo if (ret < 0) 66971f572a9SQu Wenruo goto out; 67071f572a9SQu Wenruo /* No extra backref? This means the tree block is corrupted */ 67171f572a9SQu Wenruo if (ret > 0) { 672e7d571c7SQu Wenruo ret = -EUCLEAN; 67371f572a9SQu Wenruo goto out; 67471f572a9SQu Wenruo } 67571f572a9SQu Wenruo } 6765d4f98a2SYan Zheng WARN_ON(cur->checked); 6775d4f98a2SYan Zheng if (!list_empty(&cur->upper)) { 6785d4f98a2SYan Zheng /* 67970f23fd6SJustin P. Mattock * the backref was added previously when processing 6805d4f98a2SYan Zheng * backref of type BTRFS_TREE_BLOCK_REF_KEY 6815d4f98a2SYan Zheng */ 68275bfb9afSJosef Bacik ASSERT(list_is_singular(&cur->upper)); 683a26195a5SQu Wenruo edge = list_entry(cur->upper.next, struct btrfs_backref_edge, 6845d4f98a2SYan Zheng list[LOWER]); 68575bfb9afSJosef Bacik ASSERT(list_empty(&edge->list[UPPER])); 6865d4f98a2SYan Zheng exist = edge->node[UPPER]; 6875d4f98a2SYan Zheng /* 6885d4f98a2SYan Zheng * add the upper level block to pending list if we need 6895d4f98a2SYan Zheng * check its backrefs 6905d4f98a2SYan Zheng */ 6915d4f98a2SYan Zheng if (!exist->checked) 69284780289SQu Wenruo list_add_tail(&edge->list[UPPER], &cache->pending_edge); 6935d4f98a2SYan Zheng } else { 6945d4f98a2SYan Zheng exist = NULL; 6955d4f98a2SYan Zheng } 6965d4f98a2SYan Zheng 69771f572a9SQu Wenruo for (; ret == 0; ret = btrfs_backref_iter_next(iter)) { 69871f572a9SQu Wenruo struct extent_buffer *eb; 69971f572a9SQu Wenruo struct btrfs_key key; 7003de28d57SLiu Bo int type; 70171f572a9SQu Wenruo 70271f572a9SQu Wenruo cond_resched(); 70371f572a9SQu Wenruo eb = btrfs_backref_get_eb(iter); 70471f572a9SQu Wenruo 70571f572a9SQu Wenruo key.objectid = iter->bytenr; 70671f572a9SQu Wenruo if (btrfs_backref_iter_is_inline_ref(iter)) { 70771f572a9SQu Wenruo struct btrfs_extent_inline_ref *iref; 70871f572a9SQu Wenruo 70971f572a9SQu Wenruo /* update key for inline back ref */ 71071f572a9SQu Wenruo iref = (struct btrfs_extent_inline_ref *) 71171f572a9SQu Wenruo ((unsigned long)iter->cur_ptr); 7123de28d57SLiu Bo type = btrfs_get_extent_inline_ref_type(eb, iref, 7133de28d57SLiu Bo BTRFS_REF_TYPE_BLOCK); 7143de28d57SLiu Bo if (type == BTRFS_REF_TYPE_INVALID) { 715e7d571c7SQu Wenruo ret = -EUCLEAN; 7163de28d57SLiu Bo goto out; 7173de28d57SLiu Bo } 7183de28d57SLiu Bo key.type = type; 7195d4f98a2SYan Zheng key.offset = btrfs_extent_inline_ref_offset(eb, iref); 72071f572a9SQu Wenruo } else { 72171f572a9SQu Wenruo key.type = iter->cur_key.type; 72271f572a9SQu Wenruo key.offset = iter->cur_key.offset; 7235d4f98a2SYan Zheng } 7245d4f98a2SYan Zheng 725fa6ac715SQu Wenruo /* 726fa6ac715SQu Wenruo * Parent node found and matches current inline ref, no need to 727fa6ac715SQu Wenruo * rebuild this node for this inline ref. 728fa6ac715SQu Wenruo */ 7295d4f98a2SYan Zheng if (exist && 7305d4f98a2SYan Zheng ((key.type == BTRFS_TREE_BLOCK_REF_KEY && 7315d4f98a2SYan Zheng exist->owner == key.offset) || 7325d4f98a2SYan Zheng (key.type == BTRFS_SHARED_BLOCK_REF_KEY && 7335d4f98a2SYan Zheng exist->bytenr == key.offset))) { 7345d4f98a2SYan Zheng exist = NULL; 73571f572a9SQu Wenruo continue; 7365d4f98a2SYan Zheng } 7375d4f98a2SYan Zheng 738fa6ac715SQu Wenruo /* SHARED_BLOCK_REF means key.offset is the parent bytenr */ 7395d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { 7404007ea87SQu Wenruo ret = handle_direct_tree_backref(cache, &key, cur); 741e7d571c7SQu Wenruo if (ret < 0) 7422433bea5SQu Wenruo goto out; 74371f572a9SQu Wenruo continue; 7446d8ff4e4SDavid Sterba } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) { 745e7d571c7SQu Wenruo ret = -EINVAL; 746e7d571c7SQu Wenruo btrfs_print_v0_err(fs_info); 747e7d571c7SQu Wenruo btrfs_handle_fs_error(fs_info, ret, NULL); 748ba3c2b19SNikolay Borisov goto out; 7495d4f98a2SYan Zheng } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { 75071f572a9SQu Wenruo continue; 7515d4f98a2SYan Zheng } 7525d4f98a2SYan Zheng 753fa6ac715SQu Wenruo /* 754fa6ac715SQu Wenruo * key.type == BTRFS_TREE_BLOCK_REF_KEY, inline ref offset 755fa6ac715SQu Wenruo * means the root objectid. We need to search the tree to get 756fa6ac715SQu Wenruo * its parent bytenr. 757fa6ac715SQu Wenruo */ 7584d81ea8bSQu Wenruo ret = handle_indirect_tree_backref(cache, path, &key, node_key, 7594d81ea8bSQu Wenruo cur); 760e7d571c7SQu Wenruo if (ret < 0) 76171f572a9SQu Wenruo goto out; 7625d4f98a2SYan Zheng } 76371f572a9SQu Wenruo ret = 0; 7645d4f98a2SYan Zheng cur->checked = 1; 7655d4f98a2SYan Zheng WARN_ON(exist); 766e7d571c7SQu Wenruo out: 767e7d571c7SQu Wenruo btrfs_backref_iter_release(iter); 768e7d571c7SQu Wenruo return ret; 769e7d571c7SQu Wenruo } 7705d4f98a2SYan Zheng 771e7d571c7SQu Wenruo /* 7721f872924SQu Wenruo * In handle_one_tree_backref(), we have only linked the lower node to the edge, 7731f872924SQu Wenruo * but the upper node hasn't been linked to the edge. 774a26195a5SQu Wenruo * This means we can only iterate through btrfs_backref_node::upper to reach 775a26195a5SQu Wenruo * parent edges, but not through btrfs_backref_node::lower to reach children 776a26195a5SQu Wenruo * edges. 7771f872924SQu Wenruo * 778a26195a5SQu Wenruo * This function will finish the btrfs_backref_node::lower to related edges, 779a26195a5SQu Wenruo * so that backref cache can be bi-directionally iterated. 7801f872924SQu Wenruo * 7811f872924SQu Wenruo * Also, this will add the nodes to backref cache for the next run. 7821f872924SQu Wenruo */ 783a26195a5SQu Wenruo static int finish_upper_links(struct btrfs_backref_cache *cache, 784a26195a5SQu Wenruo struct btrfs_backref_node *start) 7851f872924SQu Wenruo { 7861f872924SQu Wenruo struct list_head *useless_node = &cache->useless_node; 787a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 7881f872924SQu Wenruo struct rb_node *rb_node; 7891f872924SQu Wenruo LIST_HEAD(pending_edge); 7901f872924SQu Wenruo 7911f872924SQu Wenruo ASSERT(start->checked); 7921f872924SQu Wenruo 7931f872924SQu Wenruo /* Insert this node to cache if it's not COW-only */ 7941f872924SQu Wenruo if (!start->cowonly) { 795e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, start->bytenr, 7961f872924SQu Wenruo &start->rb_node); 7971f872924SQu Wenruo if (rb_node) 7981f872924SQu Wenruo backref_tree_panic(rb_node, -EEXIST, start->bytenr); 7991f872924SQu Wenruo list_add_tail(&start->lower, &cache->leaves); 8001f872924SQu Wenruo } 8011f872924SQu Wenruo 8021f872924SQu Wenruo /* 8031f872924SQu Wenruo * Use breadth first search to iterate all related edges. 8041f872924SQu Wenruo * 8051f872924SQu Wenruo * The starting points are all the edges of this node 8061f872924SQu Wenruo */ 8071f872924SQu Wenruo list_for_each_entry(edge, &start->upper, list[LOWER]) 8081f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &pending_edge); 8091f872924SQu Wenruo 8101f872924SQu Wenruo while (!list_empty(&pending_edge)) { 811a26195a5SQu Wenruo struct btrfs_backref_node *upper; 812a26195a5SQu Wenruo struct btrfs_backref_node *lower; 8131f872924SQu Wenruo struct rb_node *rb_node; 8141f872924SQu Wenruo 815a26195a5SQu Wenruo edge = list_first_entry(&pending_edge, 816a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 8171f872924SQu Wenruo list_del_init(&edge->list[UPPER]); 8181f872924SQu Wenruo upper = edge->node[UPPER]; 8191f872924SQu Wenruo lower = edge->node[LOWER]; 8201f872924SQu Wenruo 8211f872924SQu Wenruo /* Parent is detached, no need to keep any edges */ 8221f872924SQu Wenruo if (upper->detached) { 8231f872924SQu Wenruo list_del(&edge->list[LOWER]); 824741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 8251f872924SQu Wenruo 8261f872924SQu Wenruo /* Lower node is orphan, queue for cleanup */ 8271f872924SQu Wenruo if (list_empty(&lower->upper)) 8281f872924SQu Wenruo list_add(&lower->list, useless_node); 8291f872924SQu Wenruo continue; 8301f872924SQu Wenruo } 8311f872924SQu Wenruo 8321f872924SQu Wenruo /* 8331f872924SQu Wenruo * All new nodes added in current build_backref_tree() haven't 8341f872924SQu Wenruo * been linked to the cache rb tree. 8351f872924SQu Wenruo * So if we have upper->rb_node populated, this means a cache 8361f872924SQu Wenruo * hit. We only need to link the edge, as @upper and all its 8371f872924SQu Wenruo * parent have already been linked. 8381f872924SQu Wenruo */ 8391f872924SQu Wenruo if (!RB_EMPTY_NODE(&upper->rb_node)) { 8401f872924SQu Wenruo if (upper->lowest) { 8411f872924SQu Wenruo list_del_init(&upper->lower); 8421f872924SQu Wenruo upper->lowest = 0; 8431f872924SQu Wenruo } 8441f872924SQu Wenruo 8451f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &upper->lower); 8461f872924SQu Wenruo continue; 8471f872924SQu Wenruo } 8481f872924SQu Wenruo 8491f872924SQu Wenruo /* Sanity check, we shouldn't have any unchecked nodes */ 8501f872924SQu Wenruo if (!upper->checked) { 8511f872924SQu Wenruo ASSERT(0); 8521f872924SQu Wenruo return -EUCLEAN; 8531f872924SQu Wenruo } 8541f872924SQu Wenruo 8551f872924SQu Wenruo /* Sanity check, COW-only node has non-COW-only parent */ 8561f872924SQu Wenruo if (start->cowonly != upper->cowonly) { 8571f872924SQu Wenruo ASSERT(0); 8581f872924SQu Wenruo return -EUCLEAN; 8591f872924SQu Wenruo } 8601f872924SQu Wenruo 8611f872924SQu Wenruo /* Only cache non-COW-only (subvolume trees) tree blocks */ 8621f872924SQu Wenruo if (!upper->cowonly) { 863e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, upper->bytenr, 8641f872924SQu Wenruo &upper->rb_node); 8651f872924SQu Wenruo if (rb_node) { 8661f872924SQu Wenruo backref_tree_panic(rb_node, -EEXIST, 8671f872924SQu Wenruo upper->bytenr); 8681f872924SQu Wenruo return -EUCLEAN; 8691f872924SQu Wenruo } 8701f872924SQu Wenruo } 8711f872924SQu Wenruo 8721f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &upper->lower); 8731f872924SQu Wenruo 8741f872924SQu Wenruo /* 8751f872924SQu Wenruo * Also queue all the parent edges of this uncached node to 8761f872924SQu Wenruo * finish the upper linkage 8771f872924SQu Wenruo */ 8781f872924SQu Wenruo list_for_each_entry(edge, &upper->upper, list[LOWER]) 8791f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &pending_edge); 8801f872924SQu Wenruo } 8811f872924SQu Wenruo return 0; 8821f872924SQu Wenruo } 8831f872924SQu Wenruo 8841f872924SQu Wenruo /* 88529db137bSQu Wenruo * For useless nodes, do two major clean ups: 88629db137bSQu Wenruo * 88729db137bSQu Wenruo * - Cleanup the children edges and nodes 88829db137bSQu Wenruo * If child node is also orphan (no parent) during cleanup, then the child 88929db137bSQu Wenruo * node will also be cleaned up. 89029db137bSQu Wenruo * 89129db137bSQu Wenruo * - Freeing up leaves (level 0), keeps nodes detached 89229db137bSQu Wenruo * For nodes, the node is still cached as "detached" 89329db137bSQu Wenruo * 89429db137bSQu Wenruo * Return false if @node is not in the @useless_nodes list. 89529db137bSQu Wenruo * Return true if @node is in the @useless_nodes list. 89629db137bSQu Wenruo */ 89729db137bSQu Wenruo static bool handle_useless_nodes(struct reloc_control *rc, 898a26195a5SQu Wenruo struct btrfs_backref_node *node) 89929db137bSQu Wenruo { 900a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 90129db137bSQu Wenruo struct list_head *useless_node = &cache->useless_node; 90229db137bSQu Wenruo bool ret = false; 90329db137bSQu Wenruo 90429db137bSQu Wenruo while (!list_empty(useless_node)) { 905a26195a5SQu Wenruo struct btrfs_backref_node *cur; 90629db137bSQu Wenruo 907a26195a5SQu Wenruo cur = list_first_entry(useless_node, struct btrfs_backref_node, 90829db137bSQu Wenruo list); 90929db137bSQu Wenruo list_del_init(&cur->list); 91029db137bSQu Wenruo 91129db137bSQu Wenruo /* Only tree root nodes can be added to @useless_nodes */ 91229db137bSQu Wenruo ASSERT(list_empty(&cur->upper)); 91329db137bSQu Wenruo 91429db137bSQu Wenruo if (cur == node) 91529db137bSQu Wenruo ret = true; 91629db137bSQu Wenruo 91729db137bSQu Wenruo /* The node is the lowest node */ 91829db137bSQu Wenruo if (cur->lowest) { 91929db137bSQu Wenruo list_del_init(&cur->lower); 92029db137bSQu Wenruo cur->lowest = 0; 92129db137bSQu Wenruo } 92229db137bSQu Wenruo 92329db137bSQu Wenruo /* Cleanup the lower edges */ 92429db137bSQu Wenruo while (!list_empty(&cur->lower)) { 925a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 926a26195a5SQu Wenruo struct btrfs_backref_node *lower; 92729db137bSQu Wenruo 92829db137bSQu Wenruo edge = list_entry(cur->lower.next, 929a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 93029db137bSQu Wenruo list_del(&edge->list[UPPER]); 93129db137bSQu Wenruo list_del(&edge->list[LOWER]); 93229db137bSQu Wenruo lower = edge->node[LOWER]; 933741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 93429db137bSQu Wenruo 93529db137bSQu Wenruo /* Child node is also orphan, queue for cleanup */ 93629db137bSQu Wenruo if (list_empty(&lower->upper)) 93729db137bSQu Wenruo list_add(&lower->list, useless_node); 93829db137bSQu Wenruo } 93929db137bSQu Wenruo /* Mark this block processed for relocation */ 94029db137bSQu Wenruo mark_block_processed(rc, cur); 94129db137bSQu Wenruo 94229db137bSQu Wenruo /* 94329db137bSQu Wenruo * Backref nodes for tree leaves are deleted from the cache. 94429db137bSQu Wenruo * Backref nodes for upper level tree blocks are left in the 94529db137bSQu Wenruo * cache to avoid unnecessary backref lookup. 94629db137bSQu Wenruo */ 94729db137bSQu Wenruo if (cur->level > 0) { 94829db137bSQu Wenruo list_add(&cur->list, &cache->detached); 94929db137bSQu Wenruo cur->detached = 1; 95029db137bSQu Wenruo } else { 95129db137bSQu Wenruo rb_erase(&cur->rb_node, &cache->rb_root); 952741188d3SQu Wenruo btrfs_backref_free_node(cache, cur); 95329db137bSQu Wenruo } 95429db137bSQu Wenruo } 95529db137bSQu Wenruo return ret; 95629db137bSQu Wenruo } 95729db137bSQu Wenruo 95829db137bSQu Wenruo /* 959e7d571c7SQu Wenruo * Build backref tree for a given tree block. Root of the backref tree 960e7d571c7SQu Wenruo * corresponds the tree block, leaves of the backref tree correspond roots of 961e7d571c7SQu Wenruo * b-trees that reference the tree block. 962e7d571c7SQu Wenruo * 963e7d571c7SQu Wenruo * The basic idea of this function is check backrefs of a given block to find 964e7d571c7SQu Wenruo * upper level blocks that reference the block, and then check backrefs of 965e7d571c7SQu Wenruo * these upper level blocks recursively. The recursion stops when tree root is 966e7d571c7SQu Wenruo * reached or backrefs for the block is cached. 967e7d571c7SQu Wenruo * 968e7d571c7SQu Wenruo * NOTE: if we find that backrefs for a block are cached, we know backrefs for 969e7d571c7SQu Wenruo * all upper level blocks that directly/indirectly reference the block are also 970e7d571c7SQu Wenruo * cached. 971e7d571c7SQu Wenruo */ 972a26195a5SQu Wenruo static noinline_for_stack struct btrfs_backref_node *build_backref_tree( 973e7d571c7SQu Wenruo struct reloc_control *rc, struct btrfs_key *node_key, 974e7d571c7SQu Wenruo int level, u64 bytenr) 975e7d571c7SQu Wenruo { 976e7d571c7SQu Wenruo struct btrfs_backref_iter *iter; 977a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 978e7d571c7SQu Wenruo /* For searching parent of TREE_BLOCK_REF */ 979e7d571c7SQu Wenruo struct btrfs_path *path; 980a26195a5SQu Wenruo struct btrfs_backref_node *cur; 981a26195a5SQu Wenruo struct btrfs_backref_node *upper; 982a26195a5SQu Wenruo struct btrfs_backref_node *lower; 983a26195a5SQu Wenruo struct btrfs_backref_node *node = NULL; 984a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 985e7d571c7SQu Wenruo int ret; 986e7d571c7SQu Wenruo int err = 0; 987e7d571c7SQu Wenruo 988e7d571c7SQu Wenruo iter = btrfs_backref_iter_alloc(rc->extent_root->fs_info, GFP_NOFS); 989e7d571c7SQu Wenruo if (!iter) 990e7d571c7SQu Wenruo return ERR_PTR(-ENOMEM); 991e7d571c7SQu Wenruo path = btrfs_alloc_path(); 992e7d571c7SQu Wenruo if (!path) { 993e7d571c7SQu Wenruo err = -ENOMEM; 994e7d571c7SQu Wenruo goto out; 995e7d571c7SQu Wenruo } 996e7d571c7SQu Wenruo 997b1818dabSQu Wenruo node = btrfs_backref_alloc_node(cache, bytenr, level); 998e7d571c7SQu Wenruo if (!node) { 999e7d571c7SQu Wenruo err = -ENOMEM; 1000e7d571c7SQu Wenruo goto out; 1001e7d571c7SQu Wenruo } 1002e7d571c7SQu Wenruo 1003e7d571c7SQu Wenruo node->lowest = 1; 1004e7d571c7SQu Wenruo cur = node; 1005e7d571c7SQu Wenruo 1006e7d571c7SQu Wenruo /* Breadth-first search to build backref cache */ 1007e7d571c7SQu Wenruo do { 1008e7d571c7SQu Wenruo ret = handle_one_tree_block(cache, path, iter, node_key, cur); 1009e7d571c7SQu Wenruo if (ret < 0) { 1010e7d571c7SQu Wenruo err = ret; 1011e7d571c7SQu Wenruo goto out; 1012e7d571c7SQu Wenruo } 1013e7d571c7SQu Wenruo edge = list_first_entry_or_null(&cache->pending_edge, 1014a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 1015e7d571c7SQu Wenruo /* 1016e7d571c7SQu Wenruo * The pending list isn't empty, take the first block to 1017e7d571c7SQu Wenruo * process 1018e7d571c7SQu Wenruo */ 1019e7d571c7SQu Wenruo if (edge) { 10205d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 10215d4f98a2SYan Zheng cur = edge->node[UPPER]; 10225d4f98a2SYan Zheng } 1023e7d571c7SQu Wenruo } while (edge); 10245d4f98a2SYan Zheng 10251f872924SQu Wenruo /* Finish the upper linkage of newly added edges/nodes */ 10261f872924SQu Wenruo ret = finish_upper_links(cache, node); 10271f872924SQu Wenruo if (ret < 0) { 10281f872924SQu Wenruo err = ret; 102975bfb9afSJosef Bacik goto out; 103075bfb9afSJosef Bacik } 103175bfb9afSJosef Bacik 103229db137bSQu Wenruo if (handle_useless_nodes(rc, node)) 10333fd0a558SYan, Zheng node = NULL; 10345d4f98a2SYan Zheng out: 103571f572a9SQu Wenruo btrfs_backref_iter_free(iter); 103671f572a9SQu Wenruo btrfs_free_path(path); 10375d4f98a2SYan Zheng if (err) { 103884780289SQu Wenruo while (!list_empty(&cache->useless_node)) { 103984780289SQu Wenruo lower = list_first_entry(&cache->useless_node, 1040a26195a5SQu Wenruo struct btrfs_backref_node, list); 104175bfb9afSJosef Bacik list_del_init(&lower->list); 10423fd0a558SYan, Zheng } 104384780289SQu Wenruo while (!list_empty(&cache->pending_edge)) { 104484780289SQu Wenruo edge = list_first_entry(&cache->pending_edge, 1045a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 104675bfb9afSJosef Bacik list_del(&edge->list[UPPER]); 10473fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 104875bfb9afSJosef Bacik lower = edge->node[LOWER]; 10495d4f98a2SYan Zheng upper = edge->node[UPPER]; 1050741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 105175bfb9afSJosef Bacik 105275bfb9afSJosef Bacik /* 105375bfb9afSJosef Bacik * Lower is no longer linked to any upper backref nodes 105475bfb9afSJosef Bacik * and isn't in the cache, we can free it ourselves. 105575bfb9afSJosef Bacik */ 105675bfb9afSJosef Bacik if (list_empty(&lower->upper) && 105775bfb9afSJosef Bacik RB_EMPTY_NODE(&lower->rb_node)) 105884780289SQu Wenruo list_add(&lower->list, &cache->useless_node); 105975bfb9afSJosef Bacik 106075bfb9afSJosef Bacik if (!RB_EMPTY_NODE(&upper->rb_node)) 106175bfb9afSJosef Bacik continue; 106275bfb9afSJosef Bacik 106301327610SNicholas D Steeves /* Add this guy's upper edges to the list to process */ 106475bfb9afSJosef Bacik list_for_each_entry(edge, &upper->upper, list[LOWER]) 106584780289SQu Wenruo list_add_tail(&edge->list[UPPER], 106684780289SQu Wenruo &cache->pending_edge); 106775bfb9afSJosef Bacik if (list_empty(&upper->upper)) 106884780289SQu Wenruo list_add(&upper->list, &cache->useless_node); 106975bfb9afSJosef Bacik } 107075bfb9afSJosef Bacik 107184780289SQu Wenruo while (!list_empty(&cache->useless_node)) { 107284780289SQu Wenruo lower = list_first_entry(&cache->useless_node, 1073a26195a5SQu Wenruo struct btrfs_backref_node, list); 107475bfb9afSJosef Bacik list_del_init(&lower->list); 10750fd8c3daSLiu Bo if (lower == node) 10760fd8c3daSLiu Bo node = NULL; 1077741188d3SQu Wenruo btrfs_backref_free_node(cache, lower); 10785d4f98a2SYan Zheng } 10790fd8c3daSLiu Bo 1080023acb07SQu Wenruo btrfs_backref_cleanup_node(cache, node); 108184780289SQu Wenruo ASSERT(list_empty(&cache->useless_node) && 108284780289SQu Wenruo list_empty(&cache->pending_edge)); 10835d4f98a2SYan Zheng return ERR_PTR(err); 10845d4f98a2SYan Zheng } 108575bfb9afSJosef Bacik ASSERT(!node || !node->detached); 108684780289SQu Wenruo ASSERT(list_empty(&cache->useless_node) && 108784780289SQu Wenruo list_empty(&cache->pending_edge)); 10885d4f98a2SYan Zheng return node; 10895d4f98a2SYan Zheng } 10905d4f98a2SYan Zheng 10915d4f98a2SYan Zheng /* 10923fd0a558SYan, Zheng * helper to add backref node for the newly created snapshot. 10933fd0a558SYan, Zheng * the backref node is created by cloning backref node that 10943fd0a558SYan, Zheng * corresponds to root of source tree 10953fd0a558SYan, Zheng */ 10963fd0a558SYan, Zheng static int clone_backref_node(struct btrfs_trans_handle *trans, 10973fd0a558SYan, Zheng struct reloc_control *rc, 10983fd0a558SYan, Zheng struct btrfs_root *src, 10993fd0a558SYan, Zheng struct btrfs_root *dest) 11003fd0a558SYan, Zheng { 11013fd0a558SYan, Zheng struct btrfs_root *reloc_root = src->reloc_root; 1102a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 1103a26195a5SQu Wenruo struct btrfs_backref_node *node = NULL; 1104a26195a5SQu Wenruo struct btrfs_backref_node *new_node; 1105a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 1106a26195a5SQu Wenruo struct btrfs_backref_edge *new_edge; 11073fd0a558SYan, Zheng struct rb_node *rb_node; 11083fd0a558SYan, Zheng 11093fd0a558SYan, Zheng if (cache->last_trans > 0) 11103fd0a558SYan, Zheng update_backref_cache(trans, cache); 11113fd0a558SYan, Zheng 1112e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, src->commit_root->start); 11133fd0a558SYan, Zheng if (rb_node) { 1114a26195a5SQu Wenruo node = rb_entry(rb_node, struct btrfs_backref_node, rb_node); 11153fd0a558SYan, Zheng if (node->detached) 11163fd0a558SYan, Zheng node = NULL; 11173fd0a558SYan, Zheng else 11183fd0a558SYan, Zheng BUG_ON(node->new_bytenr != reloc_root->node->start); 11193fd0a558SYan, Zheng } 11203fd0a558SYan, Zheng 11213fd0a558SYan, Zheng if (!node) { 1122e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, 11233fd0a558SYan, Zheng reloc_root->commit_root->start); 11243fd0a558SYan, Zheng if (rb_node) { 1125a26195a5SQu Wenruo node = rb_entry(rb_node, struct btrfs_backref_node, 11263fd0a558SYan, Zheng rb_node); 11273fd0a558SYan, Zheng BUG_ON(node->detached); 11283fd0a558SYan, Zheng } 11293fd0a558SYan, Zheng } 11303fd0a558SYan, Zheng 11313fd0a558SYan, Zheng if (!node) 11323fd0a558SYan, Zheng return 0; 11333fd0a558SYan, Zheng 1134b1818dabSQu Wenruo new_node = btrfs_backref_alloc_node(cache, dest->node->start, 1135b1818dabSQu Wenruo node->level); 11363fd0a558SYan, Zheng if (!new_node) 11373fd0a558SYan, Zheng return -ENOMEM; 11383fd0a558SYan, Zheng 11393fd0a558SYan, Zheng new_node->lowest = node->lowest; 11406848ad64SYan, Zheng new_node->checked = 1; 114100246528SJosef Bacik new_node->root = btrfs_grab_root(dest); 11420b530bc5SJosef Bacik ASSERT(new_node->root); 11433fd0a558SYan, Zheng 11443fd0a558SYan, Zheng if (!node->lowest) { 11453fd0a558SYan, Zheng list_for_each_entry(edge, &node->lower, list[UPPER]) { 114647254d07SQu Wenruo new_edge = btrfs_backref_alloc_edge(cache); 11473fd0a558SYan, Zheng if (!new_edge) 11483fd0a558SYan, Zheng goto fail; 11493fd0a558SYan, Zheng 1150f39911e5SQu Wenruo btrfs_backref_link_edge(new_edge, edge->node[LOWER], 1151f39911e5SQu Wenruo new_node, LINK_UPPER); 11523fd0a558SYan, Zheng } 115376b9e23dSMiao Xie } else { 115476b9e23dSMiao Xie list_add_tail(&new_node->lower, &cache->leaves); 11553fd0a558SYan, Zheng } 11563fd0a558SYan, Zheng 1157e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, new_node->bytenr, 11583fd0a558SYan, Zheng &new_node->rb_node); 115943c04fb1SJeff Mahoney if (rb_node) 116043c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, new_node->bytenr); 11613fd0a558SYan, Zheng 11623fd0a558SYan, Zheng if (!new_node->lowest) { 11633fd0a558SYan, Zheng list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) { 11643fd0a558SYan, Zheng list_add_tail(&new_edge->list[LOWER], 11653fd0a558SYan, Zheng &new_edge->node[LOWER]->upper); 11663fd0a558SYan, Zheng } 11673fd0a558SYan, Zheng } 11683fd0a558SYan, Zheng return 0; 11693fd0a558SYan, Zheng fail: 11703fd0a558SYan, Zheng while (!list_empty(&new_node->lower)) { 11713fd0a558SYan, Zheng new_edge = list_entry(new_node->lower.next, 1172a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 11733fd0a558SYan, Zheng list_del(&new_edge->list[UPPER]); 1174741188d3SQu Wenruo btrfs_backref_free_edge(cache, new_edge); 11753fd0a558SYan, Zheng } 1176741188d3SQu Wenruo btrfs_backref_free_node(cache, new_node); 11773fd0a558SYan, Zheng return -ENOMEM; 11783fd0a558SYan, Zheng } 11793fd0a558SYan, Zheng 11803fd0a558SYan, Zheng /* 11815d4f98a2SYan Zheng * helper to add 'address of tree root -> reloc tree' mapping 11825d4f98a2SYan Zheng */ 1183ffd7b339SJeff Mahoney static int __must_check __add_reloc_root(struct btrfs_root *root) 11845d4f98a2SYan Zheng { 11850b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 11865d4f98a2SYan Zheng struct rb_node *rb_node; 11875d4f98a2SYan Zheng struct mapping_node *node; 11880b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 11895d4f98a2SYan Zheng 11905d4f98a2SYan Zheng node = kmalloc(sizeof(*node), GFP_NOFS); 1191ffd7b339SJeff Mahoney if (!node) 1192ffd7b339SJeff Mahoney return -ENOMEM; 11935d4f98a2SYan Zheng 1194ea287ab1SJosef Bacik node->bytenr = root->commit_root->start; 11955d4f98a2SYan Zheng node->data = root; 11965d4f98a2SYan Zheng 11975d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1198e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&rc->reloc_root_tree.rb_root, 11995d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12005d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 1201ffd7b339SJeff Mahoney if (rb_node) { 12020b246afaSJeff Mahoney btrfs_panic(fs_info, -EEXIST, 12035d163e0eSJeff Mahoney "Duplicate root found for start=%llu while inserting into relocation tree", 12045d163e0eSJeff Mahoney node->bytenr); 1205ffd7b339SJeff Mahoney } 12065d4f98a2SYan Zheng 12075d4f98a2SYan Zheng list_add_tail(&root->root_list, &rc->reloc_roots); 12085d4f98a2SYan Zheng return 0; 12095d4f98a2SYan Zheng } 12105d4f98a2SYan Zheng 12115d4f98a2SYan Zheng /* 1212c974c464SWang Shilong * helper to delete the 'address of tree root -> reloc tree' 12135d4f98a2SYan Zheng * mapping 12145d4f98a2SYan Zheng */ 1215c974c464SWang Shilong static void __del_reloc_root(struct btrfs_root *root) 12165d4f98a2SYan Zheng { 12170b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12185d4f98a2SYan Zheng struct rb_node *rb_node; 12195d4f98a2SYan Zheng struct mapping_node *node = NULL; 12200b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1221f44deb74SJosef Bacik bool put_ref = false; 12225d4f98a2SYan Zheng 122365c6e82bSQu Wenruo if (rc && root->node) { 12245d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1225e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, 1226ea287ab1SJosef Bacik root->commit_root->start); 1227c974c464SWang Shilong if (rb_node) { 1228c974c464SWang Shilong node = rb_entry(rb_node, struct mapping_node, rb_node); 1229c974c464SWang Shilong rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 1230ea287ab1SJosef Bacik RB_CLEAR_NODE(&node->rb_node); 1231c974c464SWang Shilong } 1232c974c464SWang Shilong spin_unlock(&rc->reloc_root_tree.lock); 1233c974c464SWang Shilong if (!node) 1234c974c464SWang Shilong return; 1235c974c464SWang Shilong BUG_ON((struct btrfs_root *)node->data != root); 1236389305b2SQu Wenruo } 1237c974c464SWang Shilong 1238f44deb74SJosef Bacik /* 1239f44deb74SJosef Bacik * We only put the reloc root here if it's on the list. There's a lot 1240f44deb74SJosef Bacik * of places where the pattern is to splice the rc->reloc_roots, process 1241f44deb74SJosef Bacik * the reloc roots, and then add the reloc root back onto 1242f44deb74SJosef Bacik * rc->reloc_roots. If we call __del_reloc_root while it's off of the 1243f44deb74SJosef Bacik * list we don't want the reference being dropped, because the guy 1244f44deb74SJosef Bacik * messing with the list is in charge of the reference. 1245f44deb74SJosef Bacik */ 12460b246afaSJeff Mahoney spin_lock(&fs_info->trans_lock); 1247f44deb74SJosef Bacik if (!list_empty(&root->root_list)) { 1248f44deb74SJosef Bacik put_ref = true; 1249c974c464SWang Shilong list_del_init(&root->root_list); 1250f44deb74SJosef Bacik } 12510b246afaSJeff Mahoney spin_unlock(&fs_info->trans_lock); 1252f44deb74SJosef Bacik if (put_ref) 1253f44deb74SJosef Bacik btrfs_put_root(root); 1254c974c464SWang Shilong kfree(node); 1255c974c464SWang Shilong } 1256c974c464SWang Shilong 1257c974c464SWang Shilong /* 1258c974c464SWang Shilong * helper to update the 'address of tree root -> reloc tree' 1259c974c464SWang Shilong * mapping 1260c974c464SWang Shilong */ 1261ea287ab1SJosef Bacik static int __update_reloc_root(struct btrfs_root *root) 1262c974c464SWang Shilong { 12630b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 1264c974c464SWang Shilong struct rb_node *rb_node; 1265c974c464SWang Shilong struct mapping_node *node = NULL; 12660b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1267c974c464SWang Shilong 1268c974c464SWang Shilong spin_lock(&rc->reloc_root_tree.lock); 1269e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, 1270ea287ab1SJosef Bacik root->commit_root->start); 12715d4f98a2SYan Zheng if (rb_node) { 12725d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 12735d4f98a2SYan Zheng rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 12745d4f98a2SYan Zheng } 12755d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 12765d4f98a2SYan Zheng 12778f71f3e0SLiu Bo if (!node) 12788f71f3e0SLiu Bo return 0; 12795d4f98a2SYan Zheng BUG_ON((struct btrfs_root *)node->data != root); 12805d4f98a2SYan Zheng 12815d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1282ea287ab1SJosef Bacik node->bytenr = root->node->start; 1283e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&rc->reloc_root_tree.rb_root, 12845d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12855d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 128643c04fb1SJeff Mahoney if (rb_node) 128743c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, node->bytenr); 12885d4f98a2SYan Zheng return 0; 12895d4f98a2SYan Zheng } 12905d4f98a2SYan Zheng 12913fd0a558SYan, Zheng static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, 12923fd0a558SYan, Zheng struct btrfs_root *root, u64 objectid) 12935d4f98a2SYan Zheng { 12940b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12955d4f98a2SYan Zheng struct btrfs_root *reloc_root; 12965d4f98a2SYan Zheng struct extent_buffer *eb; 12975d4f98a2SYan Zheng struct btrfs_root_item *root_item; 12985d4f98a2SYan Zheng struct btrfs_key root_key; 12995d4f98a2SYan Zheng int ret; 13005d4f98a2SYan Zheng 13015d4f98a2SYan Zheng root_item = kmalloc(sizeof(*root_item), GFP_NOFS); 13025d4f98a2SYan Zheng BUG_ON(!root_item); 13035d4f98a2SYan Zheng 13045d4f98a2SYan Zheng root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; 13055d4f98a2SYan Zheng root_key.type = BTRFS_ROOT_ITEM_KEY; 13063fd0a558SYan, Zheng root_key.offset = objectid; 13075d4f98a2SYan Zheng 13083fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 1309054570a1SFilipe Manana u64 commit_root_gen; 1310054570a1SFilipe Manana 13113fd0a558SYan, Zheng /* called by btrfs_init_reloc_root */ 13125d4f98a2SYan Zheng ret = btrfs_copy_root(trans, root, root->commit_root, &eb, 13135d4f98a2SYan Zheng BTRFS_TREE_RELOC_OBJECTID); 13145d4f98a2SYan Zheng BUG_ON(ret); 1315054570a1SFilipe Manana /* 1316054570a1SFilipe Manana * Set the last_snapshot field to the generation of the commit 1317054570a1SFilipe Manana * root - like this ctree.c:btrfs_block_can_be_shared() behaves 1318054570a1SFilipe Manana * correctly (returns true) when the relocation root is created 1319054570a1SFilipe Manana * either inside the critical section of a transaction commit 1320054570a1SFilipe Manana * (through transaction.c:qgroup_account_snapshot()) and when 1321054570a1SFilipe Manana * it's created before the transaction commit is started. 1322054570a1SFilipe Manana */ 1323054570a1SFilipe Manana commit_root_gen = btrfs_header_generation(root->commit_root); 1324054570a1SFilipe Manana btrfs_set_root_last_snapshot(&root->root_item, commit_root_gen); 13253fd0a558SYan, Zheng } else { 13263fd0a558SYan, Zheng /* 13273fd0a558SYan, Zheng * called by btrfs_reloc_post_snapshot_hook. 13283fd0a558SYan, Zheng * the source tree is a reloc tree, all tree blocks 13293fd0a558SYan, Zheng * modified after it was created have RELOC flag 13303fd0a558SYan, Zheng * set in their headers. so it's OK to not update 13313fd0a558SYan, Zheng * the 'last_snapshot'. 13323fd0a558SYan, Zheng */ 13333fd0a558SYan, Zheng ret = btrfs_copy_root(trans, root, root->node, &eb, 13343fd0a558SYan, Zheng BTRFS_TREE_RELOC_OBJECTID); 13353fd0a558SYan, Zheng BUG_ON(ret); 13363fd0a558SYan, Zheng } 13373fd0a558SYan, Zheng 13385d4f98a2SYan Zheng memcpy(root_item, &root->root_item, sizeof(*root_item)); 13395d4f98a2SYan Zheng btrfs_set_root_bytenr(root_item, eb->start); 13405d4f98a2SYan Zheng btrfs_set_root_level(root_item, btrfs_header_level(eb)); 13415d4f98a2SYan Zheng btrfs_set_root_generation(root_item, trans->transid); 13423fd0a558SYan, Zheng 13433fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 13443fd0a558SYan, Zheng btrfs_set_root_refs(root_item, 0); 13453fd0a558SYan, Zheng memset(&root_item->drop_progress, 0, 13463fd0a558SYan, Zheng sizeof(struct btrfs_disk_key)); 13475d4f98a2SYan Zheng root_item->drop_level = 0; 13483fd0a558SYan, Zheng } 13495d4f98a2SYan Zheng 13505d4f98a2SYan Zheng btrfs_tree_unlock(eb); 13515d4f98a2SYan Zheng free_extent_buffer(eb); 13525d4f98a2SYan Zheng 13530b246afaSJeff Mahoney ret = btrfs_insert_root(trans, fs_info->tree_root, 13545d4f98a2SYan Zheng &root_key, root_item); 13555d4f98a2SYan Zheng BUG_ON(ret); 13565d4f98a2SYan Zheng kfree(root_item); 13575d4f98a2SYan Zheng 13583dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(fs_info->tree_root, &root_key); 13595d4f98a2SYan Zheng BUG_ON(IS_ERR(reloc_root)); 13603dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 13615d4f98a2SYan Zheng reloc_root->last_trans = trans->transid; 13623fd0a558SYan, Zheng return reloc_root; 13633fd0a558SYan, Zheng } 13643fd0a558SYan, Zheng 13653fd0a558SYan, Zheng /* 13663fd0a558SYan, Zheng * create reloc tree for a given fs tree. reloc tree is just a 13673fd0a558SYan, Zheng * snapshot of the fs tree with special root objectid. 1368f44deb74SJosef Bacik * 1369f44deb74SJosef Bacik * The reloc_root comes out of here with two references, one for 1370f44deb74SJosef Bacik * root->reloc_root, and another for being on the rc->reloc_roots list. 13713fd0a558SYan, Zheng */ 13723fd0a558SYan, Zheng int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, 13733fd0a558SYan, Zheng struct btrfs_root *root) 13743fd0a558SYan, Zheng { 13750b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 13763fd0a558SYan, Zheng struct btrfs_root *reloc_root; 13770b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 137820dd2cbfSMiao Xie struct btrfs_block_rsv *rsv; 13793fd0a558SYan, Zheng int clear_rsv = 0; 1380ffd7b339SJeff Mahoney int ret; 13813fd0a558SYan, Zheng 1382aec7db3bSJosef Bacik if (!rc) 13832abc726aSJosef Bacik return 0; 13842abc726aSJosef Bacik 13851fac4a54SQu Wenruo /* 13861fac4a54SQu Wenruo * The subvolume has reloc tree but the swap is finished, no need to 13871fac4a54SQu Wenruo * create/update the dead reloc tree 13881fac4a54SQu Wenruo */ 13896282675eSQu Wenruo if (reloc_root_is_dead(root)) 13901fac4a54SQu Wenruo return 0; 13911fac4a54SQu Wenruo 1392aec7db3bSJosef Bacik /* 1393aec7db3bSJosef Bacik * This is subtle but important. We do not do 1394aec7db3bSJosef Bacik * record_root_in_transaction for reloc roots, instead we record their 1395aec7db3bSJosef Bacik * corresponding fs root, and then here we update the last trans for the 1396aec7db3bSJosef Bacik * reloc root. This means that we have to do this for the entire life 1397aec7db3bSJosef Bacik * of the reloc root, regardless of which stage of the relocation we are 1398aec7db3bSJosef Bacik * in. 1399aec7db3bSJosef Bacik */ 14003fd0a558SYan, Zheng if (root->reloc_root) { 14013fd0a558SYan, Zheng reloc_root = root->reloc_root; 14023fd0a558SYan, Zheng reloc_root->last_trans = trans->transid; 14033fd0a558SYan, Zheng return 0; 14043fd0a558SYan, Zheng } 14053fd0a558SYan, Zheng 1406aec7db3bSJosef Bacik /* 1407aec7db3bSJosef Bacik * We are merging reloc roots, we do not need new reloc trees. Also 1408aec7db3bSJosef Bacik * reloc trees never need their own reloc tree. 1409aec7db3bSJosef Bacik */ 1410aec7db3bSJosef Bacik if (!rc->create_reloc_tree || 1411aec7db3bSJosef Bacik root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 1412aec7db3bSJosef Bacik return 0; 1413aec7db3bSJosef Bacik 141420dd2cbfSMiao Xie if (!trans->reloc_reserved) { 141520dd2cbfSMiao Xie rsv = trans->block_rsv; 14163fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 14173fd0a558SYan, Zheng clear_rsv = 1; 14183fd0a558SYan, Zheng } 14193fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root, root->root_key.objectid); 14203fd0a558SYan, Zheng if (clear_rsv) 142120dd2cbfSMiao Xie trans->block_rsv = rsv; 14225d4f98a2SYan Zheng 1423ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 1424ffd7b339SJeff Mahoney BUG_ON(ret < 0); 1425f44deb74SJosef Bacik root->reloc_root = btrfs_grab_root(reloc_root); 14265d4f98a2SYan Zheng return 0; 14275d4f98a2SYan Zheng } 14285d4f98a2SYan Zheng 14295d4f98a2SYan Zheng /* 14305d4f98a2SYan Zheng * update root item of reloc tree 14315d4f98a2SYan Zheng */ 14325d4f98a2SYan Zheng int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, 14335d4f98a2SYan Zheng struct btrfs_root *root) 14345d4f98a2SYan Zheng { 14350b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 14365d4f98a2SYan Zheng struct btrfs_root *reloc_root; 14375d4f98a2SYan Zheng struct btrfs_root_item *root_item; 14385d4f98a2SYan Zheng int ret; 14395d4f98a2SYan Zheng 14406282675eSQu Wenruo if (!have_reloc_root(root)) 14417585717fSChris Mason goto out; 14425d4f98a2SYan Zheng 14435d4f98a2SYan Zheng reloc_root = root->reloc_root; 14445d4f98a2SYan Zheng root_item = &reloc_root->root_item; 14455d4f98a2SYan Zheng 1446f44deb74SJosef Bacik /* 1447f44deb74SJosef Bacik * We are probably ok here, but __del_reloc_root() will drop its ref of 1448f44deb74SJosef Bacik * the root. We have the ref for root->reloc_root, but just in case 1449f44deb74SJosef Bacik * hold it while we update the reloc root. 1450f44deb74SJosef Bacik */ 1451f44deb74SJosef Bacik btrfs_grab_root(reloc_root); 1452f44deb74SJosef Bacik 1453d2311e69SQu Wenruo /* root->reloc_root will stay until current relocation finished */ 14540b246afaSJeff Mahoney if (fs_info->reloc_ctl->merge_reloc_tree && 14553fd0a558SYan, Zheng btrfs_root_refs(root_item) == 0) { 1456d2311e69SQu Wenruo set_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 14576282675eSQu Wenruo /* 14586282675eSQu Wenruo * Mark the tree as dead before we change reloc_root so 14596282675eSQu Wenruo * have_reloc_root will not touch it from now on. 14606282675eSQu Wenruo */ 14616282675eSQu Wenruo smp_wmb(); 1462c974c464SWang Shilong __del_reloc_root(reloc_root); 14635d4f98a2SYan Zheng } 14645d4f98a2SYan Zheng 14655d4f98a2SYan Zheng if (reloc_root->commit_root != reloc_root->node) { 1466ea287ab1SJosef Bacik __update_reloc_root(reloc_root); 14675d4f98a2SYan Zheng btrfs_set_root_node(root_item, reloc_root->node); 14685d4f98a2SYan Zheng free_extent_buffer(reloc_root->commit_root); 14695d4f98a2SYan Zheng reloc_root->commit_root = btrfs_root_node(reloc_root); 14705d4f98a2SYan Zheng } 14715d4f98a2SYan Zheng 14720b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 14735d4f98a2SYan Zheng &reloc_root->root_key, root_item); 14745d4f98a2SYan Zheng BUG_ON(ret); 1475f44deb74SJosef Bacik btrfs_put_root(reloc_root); 14767585717fSChris Mason out: 14775d4f98a2SYan Zheng return 0; 14785d4f98a2SYan Zheng } 14795d4f98a2SYan Zheng 14805d4f98a2SYan Zheng /* 14815d4f98a2SYan Zheng * helper to find first cached inode with inode number >= objectid 14825d4f98a2SYan Zheng * in a subvolume 14835d4f98a2SYan Zheng */ 14845d4f98a2SYan Zheng static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) 14855d4f98a2SYan Zheng { 14865d4f98a2SYan Zheng struct rb_node *node; 14875d4f98a2SYan Zheng struct rb_node *prev; 14885d4f98a2SYan Zheng struct btrfs_inode *entry; 14895d4f98a2SYan Zheng struct inode *inode; 14905d4f98a2SYan Zheng 14915d4f98a2SYan Zheng spin_lock(&root->inode_lock); 14925d4f98a2SYan Zheng again: 14935d4f98a2SYan Zheng node = root->inode_tree.rb_node; 14945d4f98a2SYan Zheng prev = NULL; 14955d4f98a2SYan Zheng while (node) { 14965d4f98a2SYan Zheng prev = node; 14975d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 14985d4f98a2SYan Zheng 14994a0cc7caSNikolay Borisov if (objectid < btrfs_ino(entry)) 15005d4f98a2SYan Zheng node = node->rb_left; 15014a0cc7caSNikolay Borisov else if (objectid > btrfs_ino(entry)) 15025d4f98a2SYan Zheng node = node->rb_right; 15035d4f98a2SYan Zheng else 15045d4f98a2SYan Zheng break; 15055d4f98a2SYan Zheng } 15065d4f98a2SYan Zheng if (!node) { 15075d4f98a2SYan Zheng while (prev) { 15085d4f98a2SYan Zheng entry = rb_entry(prev, struct btrfs_inode, rb_node); 15094a0cc7caSNikolay Borisov if (objectid <= btrfs_ino(entry)) { 15105d4f98a2SYan Zheng node = prev; 15115d4f98a2SYan Zheng break; 15125d4f98a2SYan Zheng } 15135d4f98a2SYan Zheng prev = rb_next(prev); 15145d4f98a2SYan Zheng } 15155d4f98a2SYan Zheng } 15165d4f98a2SYan Zheng while (node) { 15175d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 15185d4f98a2SYan Zheng inode = igrab(&entry->vfs_inode); 15195d4f98a2SYan Zheng if (inode) { 15205d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 15215d4f98a2SYan Zheng return inode; 15225d4f98a2SYan Zheng } 15235d4f98a2SYan Zheng 15244a0cc7caSNikolay Borisov objectid = btrfs_ino(entry) + 1; 15255d4f98a2SYan Zheng if (cond_resched_lock(&root->inode_lock)) 15265d4f98a2SYan Zheng goto again; 15275d4f98a2SYan Zheng 15285d4f98a2SYan Zheng node = rb_next(node); 15295d4f98a2SYan Zheng } 15305d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 15315d4f98a2SYan Zheng return NULL; 15325d4f98a2SYan Zheng } 15335d4f98a2SYan Zheng 15345d4f98a2SYan Zheng /* 15355d4f98a2SYan Zheng * get new location of data 15365d4f98a2SYan Zheng */ 15375d4f98a2SYan Zheng static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, 15385d4f98a2SYan Zheng u64 bytenr, u64 num_bytes) 15395d4f98a2SYan Zheng { 15405d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(reloc_inode)->root; 15415d4f98a2SYan Zheng struct btrfs_path *path; 15425d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 15435d4f98a2SYan Zheng struct extent_buffer *leaf; 15445d4f98a2SYan Zheng int ret; 15455d4f98a2SYan Zheng 15465d4f98a2SYan Zheng path = btrfs_alloc_path(); 15475d4f98a2SYan Zheng if (!path) 15485d4f98a2SYan Zheng return -ENOMEM; 15495d4f98a2SYan Zheng 15505d4f98a2SYan Zheng bytenr -= BTRFS_I(reloc_inode)->index_cnt; 1551f85b7379SDavid Sterba ret = btrfs_lookup_file_extent(NULL, root, path, 1552f85b7379SDavid Sterba btrfs_ino(BTRFS_I(reloc_inode)), bytenr, 0); 15535d4f98a2SYan Zheng if (ret < 0) 15545d4f98a2SYan Zheng goto out; 15555d4f98a2SYan Zheng if (ret > 0) { 15565d4f98a2SYan Zheng ret = -ENOENT; 15575d4f98a2SYan Zheng goto out; 15585d4f98a2SYan Zheng } 15595d4f98a2SYan Zheng 15605d4f98a2SYan Zheng leaf = path->nodes[0]; 15615d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, path->slots[0], 15625d4f98a2SYan Zheng struct btrfs_file_extent_item); 15635d4f98a2SYan Zheng 15645d4f98a2SYan Zheng BUG_ON(btrfs_file_extent_offset(leaf, fi) || 15655d4f98a2SYan Zheng btrfs_file_extent_compression(leaf, fi) || 15665d4f98a2SYan Zheng btrfs_file_extent_encryption(leaf, fi) || 15675d4f98a2SYan Zheng btrfs_file_extent_other_encoding(leaf, fi)); 15685d4f98a2SYan Zheng 15695d4f98a2SYan Zheng if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { 157083d4cfd4SJosef Bacik ret = -EINVAL; 15715d4f98a2SYan Zheng goto out; 15725d4f98a2SYan Zheng } 15735d4f98a2SYan Zheng 15745d4f98a2SYan Zheng *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 15755d4f98a2SYan Zheng ret = 0; 15765d4f98a2SYan Zheng out: 15775d4f98a2SYan Zheng btrfs_free_path(path); 15785d4f98a2SYan Zheng return ret; 15795d4f98a2SYan Zheng } 15805d4f98a2SYan Zheng 15815d4f98a2SYan Zheng /* 15825d4f98a2SYan Zheng * update file extent items in the tree leaf to point to 15835d4f98a2SYan Zheng * the new locations. 15845d4f98a2SYan Zheng */ 15853fd0a558SYan, Zheng static noinline_for_stack 15863fd0a558SYan, Zheng int replace_file_extents(struct btrfs_trans_handle *trans, 15875d4f98a2SYan Zheng struct reloc_control *rc, 15885d4f98a2SYan Zheng struct btrfs_root *root, 15893fd0a558SYan, Zheng struct extent_buffer *leaf) 15905d4f98a2SYan Zheng { 15910b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 15925d4f98a2SYan Zheng struct btrfs_key key; 15935d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 15945d4f98a2SYan Zheng struct inode *inode = NULL; 15955d4f98a2SYan Zheng u64 parent; 15965d4f98a2SYan Zheng u64 bytenr; 15973fd0a558SYan, Zheng u64 new_bytenr = 0; 15985d4f98a2SYan Zheng u64 num_bytes; 15995d4f98a2SYan Zheng u64 end; 16005d4f98a2SYan Zheng u32 nritems; 16015d4f98a2SYan Zheng u32 i; 160283d4cfd4SJosef Bacik int ret = 0; 16035d4f98a2SYan Zheng int first = 1; 16045d4f98a2SYan Zheng int dirty = 0; 16055d4f98a2SYan Zheng 16065d4f98a2SYan Zheng if (rc->stage != UPDATE_DATA_PTRS) 16075d4f98a2SYan Zheng return 0; 16085d4f98a2SYan Zheng 16095d4f98a2SYan Zheng /* reloc trees always use full backref */ 16105d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 16115d4f98a2SYan Zheng parent = leaf->start; 16125d4f98a2SYan Zheng else 16135d4f98a2SYan Zheng parent = 0; 16145d4f98a2SYan Zheng 16155d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 16165d4f98a2SYan Zheng for (i = 0; i < nritems; i++) { 161782fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 161882fa113fSQu Wenruo 16195d4f98a2SYan Zheng cond_resched(); 16205d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, i); 16215d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_DATA_KEY) 16225d4f98a2SYan Zheng continue; 16235d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 16245d4f98a2SYan Zheng if (btrfs_file_extent_type(leaf, fi) == 16255d4f98a2SYan Zheng BTRFS_FILE_EXTENT_INLINE) 16265d4f98a2SYan Zheng continue; 16275d4f98a2SYan Zheng bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 16285d4f98a2SYan Zheng num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); 16295d4f98a2SYan Zheng if (bytenr == 0) 16305d4f98a2SYan Zheng continue; 16319569cc20SQu Wenruo if (!in_range(bytenr, rc->block_group->start, 16329569cc20SQu Wenruo rc->block_group->length)) 16335d4f98a2SYan Zheng continue; 16345d4f98a2SYan Zheng 16355d4f98a2SYan Zheng /* 16365d4f98a2SYan Zheng * if we are modifying block in fs tree, wait for readpage 16375d4f98a2SYan Zheng * to complete and drop the extent cache 16385d4f98a2SYan Zheng */ 16395d4f98a2SYan Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 16405d4f98a2SYan Zheng if (first) { 16415d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 16425d4f98a2SYan Zheng first = 0; 16434a0cc7caSNikolay Borisov } else if (inode && btrfs_ino(BTRFS_I(inode)) < key.objectid) { 16443fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 16455d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 16465d4f98a2SYan Zheng } 16474a0cc7caSNikolay Borisov if (inode && btrfs_ino(BTRFS_I(inode)) == key.objectid) { 16485d4f98a2SYan Zheng end = key.offset + 16495d4f98a2SYan Zheng btrfs_file_extent_num_bytes(leaf, fi); 16505d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(key.offset, 16510b246afaSJeff Mahoney fs_info->sectorsize)); 16520b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 16535d4f98a2SYan Zheng end--; 16545d4f98a2SYan Zheng ret = try_lock_extent(&BTRFS_I(inode)->io_tree, 1655d0082371SJeff Mahoney key.offset, end); 16565d4f98a2SYan Zheng if (!ret) 16575d4f98a2SYan Zheng continue; 16585d4f98a2SYan Zheng 1659dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), 1660dcdbc059SNikolay Borisov key.offset, end, 1); 16615d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 1662d0082371SJeff Mahoney key.offset, end); 16635d4f98a2SYan Zheng } 16645d4f98a2SYan Zheng } 16655d4f98a2SYan Zheng 16665d4f98a2SYan Zheng ret = get_new_location(rc->data_inode, &new_bytenr, 16675d4f98a2SYan Zheng bytenr, num_bytes); 166883d4cfd4SJosef Bacik if (ret) { 166983d4cfd4SJosef Bacik /* 167083d4cfd4SJosef Bacik * Don't have to abort since we've not changed anything 167183d4cfd4SJosef Bacik * in the file extent yet. 167283d4cfd4SJosef Bacik */ 167383d4cfd4SJosef Bacik break; 16743fd0a558SYan, Zheng } 16755d4f98a2SYan Zheng 16765d4f98a2SYan Zheng btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); 16775d4f98a2SYan Zheng dirty = 1; 16785d4f98a2SYan Zheng 16795d4f98a2SYan Zheng key.offset -= btrfs_file_extent_offset(leaf, fi); 168082fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 168182fa113fSQu Wenruo num_bytes, parent); 168282fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 168382fa113fSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1684b06c4bf5SFilipe Manana key.objectid, key.offset); 168582fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 168683d4cfd4SJosef Bacik if (ret) { 168766642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 168883d4cfd4SJosef Bacik break; 168983d4cfd4SJosef Bacik } 16905d4f98a2SYan Zheng 1691ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr, 1692ffd4bb2aSQu Wenruo num_bytes, parent); 1693ffd4bb2aSQu Wenruo ref.real_root = root->root_key.objectid; 1694ffd4bb2aSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1695b06c4bf5SFilipe Manana key.objectid, key.offset); 1696ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 169783d4cfd4SJosef Bacik if (ret) { 169866642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 169983d4cfd4SJosef Bacik break; 170083d4cfd4SJosef Bacik } 17015d4f98a2SYan Zheng } 17025d4f98a2SYan Zheng if (dirty) 17035d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 17043fd0a558SYan, Zheng if (inode) 17053fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 170683d4cfd4SJosef Bacik return ret; 17075d4f98a2SYan Zheng } 17085d4f98a2SYan Zheng 17095d4f98a2SYan Zheng static noinline_for_stack 17105d4f98a2SYan Zheng int memcmp_node_keys(struct extent_buffer *eb, int slot, 17115d4f98a2SYan Zheng struct btrfs_path *path, int level) 17125d4f98a2SYan Zheng { 17135d4f98a2SYan Zheng struct btrfs_disk_key key1; 17145d4f98a2SYan Zheng struct btrfs_disk_key key2; 17155d4f98a2SYan Zheng btrfs_node_key(eb, &key1, slot); 17165d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &key2, path->slots[level]); 17175d4f98a2SYan Zheng return memcmp(&key1, &key2, sizeof(key1)); 17185d4f98a2SYan Zheng } 17195d4f98a2SYan Zheng 17205d4f98a2SYan Zheng /* 17215d4f98a2SYan Zheng * try to replace tree blocks in fs tree with the new blocks 17225d4f98a2SYan Zheng * in reloc tree. tree blocks haven't been modified since the 17235d4f98a2SYan Zheng * reloc tree was create can be replaced. 17245d4f98a2SYan Zheng * 17255d4f98a2SYan Zheng * if a block was replaced, level of the block + 1 is returned. 17265d4f98a2SYan Zheng * if no block got replaced, 0 is returned. if there are other 17275d4f98a2SYan Zheng * errors, a negative error number is returned. 17285d4f98a2SYan Zheng */ 17293fd0a558SYan, Zheng static noinline_for_stack 17303d0174f7SQu Wenruo int replace_path(struct btrfs_trans_handle *trans, struct reloc_control *rc, 17315d4f98a2SYan Zheng struct btrfs_root *dest, struct btrfs_root *src, 17325d4f98a2SYan Zheng struct btrfs_path *path, struct btrfs_key *next_key, 17335d4f98a2SYan Zheng int lowest_level, int max_level) 17345d4f98a2SYan Zheng { 17350b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = dest->fs_info; 17365d4f98a2SYan Zheng struct extent_buffer *eb; 17375d4f98a2SYan Zheng struct extent_buffer *parent; 173882fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 17395d4f98a2SYan Zheng struct btrfs_key key; 17405d4f98a2SYan Zheng u64 old_bytenr; 17415d4f98a2SYan Zheng u64 new_bytenr; 17425d4f98a2SYan Zheng u64 old_ptr_gen; 17435d4f98a2SYan Zheng u64 new_ptr_gen; 17445d4f98a2SYan Zheng u64 last_snapshot; 17455d4f98a2SYan Zheng u32 blocksize; 17463fd0a558SYan, Zheng int cow = 0; 17475d4f98a2SYan Zheng int level; 17485d4f98a2SYan Zheng int ret; 17495d4f98a2SYan Zheng int slot; 17505d4f98a2SYan Zheng 17515d4f98a2SYan Zheng BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 17525d4f98a2SYan Zheng BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); 17535d4f98a2SYan Zheng 17545d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&src->root_item); 17553fd0a558SYan, Zheng again: 17565d4f98a2SYan Zheng slot = path->slots[lowest_level]; 17575d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); 17585d4f98a2SYan Zheng 17595d4f98a2SYan Zheng eb = btrfs_lock_root_node(dest); 17608bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 17615d4f98a2SYan Zheng level = btrfs_header_level(eb); 17625d4f98a2SYan Zheng 17635d4f98a2SYan Zheng if (level < lowest_level) { 17645d4f98a2SYan Zheng btrfs_tree_unlock(eb); 17655d4f98a2SYan Zheng free_extent_buffer(eb); 17665d4f98a2SYan Zheng return 0; 17675d4f98a2SYan Zheng } 17685d4f98a2SYan Zheng 17693fd0a558SYan, Zheng if (cow) { 17705d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); 17715d4f98a2SYan Zheng BUG_ON(ret); 17723fd0a558SYan, Zheng } 17738bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 17745d4f98a2SYan Zheng 17755d4f98a2SYan Zheng if (next_key) { 17765d4f98a2SYan Zheng next_key->objectid = (u64)-1; 17775d4f98a2SYan Zheng next_key->type = (u8)-1; 17785d4f98a2SYan Zheng next_key->offset = (u64)-1; 17795d4f98a2SYan Zheng } 17805d4f98a2SYan Zheng 17815d4f98a2SYan Zheng parent = eb; 17825d4f98a2SYan Zheng while (1) { 1783581c1760SQu Wenruo struct btrfs_key first_key; 1784581c1760SQu Wenruo 17855d4f98a2SYan Zheng level = btrfs_header_level(parent); 17865d4f98a2SYan Zheng BUG_ON(level < lowest_level); 17875d4f98a2SYan Zheng 17885d4f98a2SYan Zheng ret = btrfs_bin_search(parent, &key, level, &slot); 1789cbca7d59SFilipe Manana if (ret < 0) 1790cbca7d59SFilipe Manana break; 17915d4f98a2SYan Zheng if (ret && slot > 0) 17925d4f98a2SYan Zheng slot--; 17935d4f98a2SYan Zheng 17945d4f98a2SYan Zheng if (next_key && slot + 1 < btrfs_header_nritems(parent)) 17955d4f98a2SYan Zheng btrfs_node_key_to_cpu(parent, next_key, slot + 1); 17965d4f98a2SYan Zheng 17975d4f98a2SYan Zheng old_bytenr = btrfs_node_blockptr(parent, slot); 17980b246afaSJeff Mahoney blocksize = fs_info->nodesize; 17995d4f98a2SYan Zheng old_ptr_gen = btrfs_node_ptr_generation(parent, slot); 180017515f1bSQu Wenruo btrfs_node_key_to_cpu(parent, &first_key, slot); 18015d4f98a2SYan Zheng 18025d4f98a2SYan Zheng if (level <= max_level) { 18035d4f98a2SYan Zheng eb = path->nodes[level]; 18045d4f98a2SYan Zheng new_bytenr = btrfs_node_blockptr(eb, 18055d4f98a2SYan Zheng path->slots[level]); 18065d4f98a2SYan Zheng new_ptr_gen = btrfs_node_ptr_generation(eb, 18075d4f98a2SYan Zheng path->slots[level]); 18085d4f98a2SYan Zheng } else { 18095d4f98a2SYan Zheng new_bytenr = 0; 18105d4f98a2SYan Zheng new_ptr_gen = 0; 18115d4f98a2SYan Zheng } 18125d4f98a2SYan Zheng 1813fae7f21cSDulshani Gunawardhana if (WARN_ON(new_bytenr > 0 && new_bytenr == old_bytenr)) { 18145d4f98a2SYan Zheng ret = level; 18155d4f98a2SYan Zheng break; 18165d4f98a2SYan Zheng } 18175d4f98a2SYan Zheng 18185d4f98a2SYan Zheng if (new_bytenr == 0 || old_ptr_gen > last_snapshot || 18195d4f98a2SYan Zheng memcmp_node_keys(parent, slot, path, level)) { 18203fd0a558SYan, Zheng if (level <= lowest_level) { 18215d4f98a2SYan Zheng ret = 0; 18225d4f98a2SYan Zheng break; 18235d4f98a2SYan Zheng } 18245d4f98a2SYan Zheng 1825581c1760SQu Wenruo eb = read_tree_block(fs_info, old_bytenr, old_ptr_gen, 1826581c1760SQu Wenruo level - 1, &first_key); 182764c043deSLiu Bo if (IS_ERR(eb)) { 182864c043deSLiu Bo ret = PTR_ERR(eb); 1829264813acSLiu Bo break; 183064c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 183164c043deSLiu Bo ret = -EIO; 1832416bc658SJosef Bacik free_extent_buffer(eb); 1833379cde74SStefan Behrens break; 1834416bc658SJosef Bacik } 18355d4f98a2SYan Zheng btrfs_tree_lock(eb); 18363fd0a558SYan, Zheng if (cow) { 18375d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, parent, 18385d4f98a2SYan Zheng slot, &eb); 18395d4f98a2SYan Zheng BUG_ON(ret); 18405d4f98a2SYan Zheng } 18418bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 18425d4f98a2SYan Zheng 18435d4f98a2SYan Zheng btrfs_tree_unlock(parent); 18445d4f98a2SYan Zheng free_extent_buffer(parent); 18455d4f98a2SYan Zheng 18465d4f98a2SYan Zheng parent = eb; 18475d4f98a2SYan Zheng continue; 18485d4f98a2SYan Zheng } 18495d4f98a2SYan Zheng 18503fd0a558SYan, Zheng if (!cow) { 18513fd0a558SYan, Zheng btrfs_tree_unlock(parent); 18523fd0a558SYan, Zheng free_extent_buffer(parent); 18533fd0a558SYan, Zheng cow = 1; 18543fd0a558SYan, Zheng goto again; 18553fd0a558SYan, Zheng } 18563fd0a558SYan, Zheng 18575d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 18585d4f98a2SYan Zheng path->slots[level]); 1859b3b4aa74SDavid Sterba btrfs_release_path(path); 18605d4f98a2SYan Zheng 18615d4f98a2SYan Zheng path->lowest_level = level; 18625d4f98a2SYan Zheng ret = btrfs_search_slot(trans, src, &key, path, 0, 1); 18635d4f98a2SYan Zheng path->lowest_level = 0; 18645d4f98a2SYan Zheng BUG_ON(ret); 18655d4f98a2SYan Zheng 18665d4f98a2SYan Zheng /* 1867824d8dffSQu Wenruo * Info qgroup to trace both subtrees. 1868824d8dffSQu Wenruo * 1869824d8dffSQu Wenruo * We must trace both trees. 1870824d8dffSQu Wenruo * 1) Tree reloc subtree 1871824d8dffSQu Wenruo * If not traced, we will leak data numbers 1872824d8dffSQu Wenruo * 2) Fs subtree 1873824d8dffSQu Wenruo * If not traced, we will double count old data 1874f616f5cdSQu Wenruo * 1875f616f5cdSQu Wenruo * We don't scan the subtree right now, but only record 1876f616f5cdSQu Wenruo * the swapped tree blocks. 1877f616f5cdSQu Wenruo * The real subtree rescan is delayed until we have new 1878f616f5cdSQu Wenruo * CoW on the subtree root node before transaction commit. 1879824d8dffSQu Wenruo */ 1880370a11b8SQu Wenruo ret = btrfs_qgroup_add_swapped_blocks(trans, dest, 1881370a11b8SQu Wenruo rc->block_group, parent, slot, 1882370a11b8SQu Wenruo path->nodes[level], path->slots[level], 1883370a11b8SQu Wenruo last_snapshot); 1884370a11b8SQu Wenruo if (ret < 0) 1885370a11b8SQu Wenruo break; 1886824d8dffSQu Wenruo /* 18875d4f98a2SYan Zheng * swap blocks in fs tree and reloc tree. 18885d4f98a2SYan Zheng */ 18895d4f98a2SYan Zheng btrfs_set_node_blockptr(parent, slot, new_bytenr); 18905d4f98a2SYan Zheng btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); 18915d4f98a2SYan Zheng btrfs_mark_buffer_dirty(parent); 18925d4f98a2SYan Zheng 18935d4f98a2SYan Zheng btrfs_set_node_blockptr(path->nodes[level], 18945d4f98a2SYan Zheng path->slots[level], old_bytenr); 18955d4f98a2SYan Zheng btrfs_set_node_ptr_generation(path->nodes[level], 18965d4f98a2SYan Zheng path->slots[level], old_ptr_gen); 18975d4f98a2SYan Zheng btrfs_mark_buffer_dirty(path->nodes[level]); 18985d4f98a2SYan Zheng 189982fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, old_bytenr, 190082fa113fSQu Wenruo blocksize, path->nodes[level]->start); 190182fa113fSQu Wenruo ref.skip_qgroup = true; 190282fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 190382fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 19045d4f98a2SYan Zheng BUG_ON(ret); 190582fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 190682fa113fSQu Wenruo blocksize, 0); 190782fa113fSQu Wenruo ref.skip_qgroup = true; 190882fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 190982fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 19105d4f98a2SYan Zheng BUG_ON(ret); 19115d4f98a2SYan Zheng 1912ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, new_bytenr, 1913ffd4bb2aSQu Wenruo blocksize, path->nodes[level]->start); 1914ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 1915ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 1916ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 19175d4f98a2SYan Zheng BUG_ON(ret); 19185d4f98a2SYan Zheng 1919ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, old_bytenr, 1920ffd4bb2aSQu Wenruo blocksize, 0); 1921ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 1922ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 1923ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 19245d4f98a2SYan Zheng BUG_ON(ret); 19255d4f98a2SYan Zheng 19265d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 19275d4f98a2SYan Zheng 19285d4f98a2SYan Zheng ret = level; 19295d4f98a2SYan Zheng break; 19305d4f98a2SYan Zheng } 19315d4f98a2SYan Zheng btrfs_tree_unlock(parent); 19325d4f98a2SYan Zheng free_extent_buffer(parent); 19335d4f98a2SYan Zheng return ret; 19345d4f98a2SYan Zheng } 19355d4f98a2SYan Zheng 19365d4f98a2SYan Zheng /* 19375d4f98a2SYan Zheng * helper to find next relocated block in reloc tree 19385d4f98a2SYan Zheng */ 19395d4f98a2SYan Zheng static noinline_for_stack 19405d4f98a2SYan Zheng int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 19415d4f98a2SYan Zheng int *level) 19425d4f98a2SYan Zheng { 19435d4f98a2SYan Zheng struct extent_buffer *eb; 19445d4f98a2SYan Zheng int i; 19455d4f98a2SYan Zheng u64 last_snapshot; 19465d4f98a2SYan Zheng u32 nritems; 19475d4f98a2SYan Zheng 19485d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 19495d4f98a2SYan Zheng 19505d4f98a2SYan Zheng for (i = 0; i < *level; i++) { 19515d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 19525d4f98a2SYan Zheng path->nodes[i] = NULL; 19535d4f98a2SYan Zheng } 19545d4f98a2SYan Zheng 19555d4f98a2SYan Zheng for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { 19565d4f98a2SYan Zheng eb = path->nodes[i]; 19575d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 19585d4f98a2SYan Zheng while (path->slots[i] + 1 < nritems) { 19595d4f98a2SYan Zheng path->slots[i]++; 19605d4f98a2SYan Zheng if (btrfs_node_ptr_generation(eb, path->slots[i]) <= 19615d4f98a2SYan Zheng last_snapshot) 19625d4f98a2SYan Zheng continue; 19635d4f98a2SYan Zheng 19645d4f98a2SYan Zheng *level = i; 19655d4f98a2SYan Zheng return 0; 19665d4f98a2SYan Zheng } 19675d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 19685d4f98a2SYan Zheng path->nodes[i] = NULL; 19695d4f98a2SYan Zheng } 19705d4f98a2SYan Zheng return 1; 19715d4f98a2SYan Zheng } 19725d4f98a2SYan Zheng 19735d4f98a2SYan Zheng /* 19745d4f98a2SYan Zheng * walk down reloc tree to find relocated block of lowest level 19755d4f98a2SYan Zheng */ 19765d4f98a2SYan Zheng static noinline_for_stack 19775d4f98a2SYan Zheng int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 19785d4f98a2SYan Zheng int *level) 19795d4f98a2SYan Zheng { 19802ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 19815d4f98a2SYan Zheng struct extent_buffer *eb = NULL; 19825d4f98a2SYan Zheng int i; 19835d4f98a2SYan Zheng u64 bytenr; 19845d4f98a2SYan Zheng u64 ptr_gen = 0; 19855d4f98a2SYan Zheng u64 last_snapshot; 19865d4f98a2SYan Zheng u32 nritems; 19875d4f98a2SYan Zheng 19885d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 19895d4f98a2SYan Zheng 19905d4f98a2SYan Zheng for (i = *level; i > 0; i--) { 1991581c1760SQu Wenruo struct btrfs_key first_key; 1992581c1760SQu Wenruo 19935d4f98a2SYan Zheng eb = path->nodes[i]; 19945d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 19955d4f98a2SYan Zheng while (path->slots[i] < nritems) { 19965d4f98a2SYan Zheng ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); 19975d4f98a2SYan Zheng if (ptr_gen > last_snapshot) 19985d4f98a2SYan Zheng break; 19995d4f98a2SYan Zheng path->slots[i]++; 20005d4f98a2SYan Zheng } 20015d4f98a2SYan Zheng if (path->slots[i] >= nritems) { 20025d4f98a2SYan Zheng if (i == *level) 20035d4f98a2SYan Zheng break; 20045d4f98a2SYan Zheng *level = i + 1; 20055d4f98a2SYan Zheng return 0; 20065d4f98a2SYan Zheng } 20075d4f98a2SYan Zheng if (i == 1) { 20085d4f98a2SYan Zheng *level = i; 20095d4f98a2SYan Zheng return 0; 20105d4f98a2SYan Zheng } 20115d4f98a2SYan Zheng 20125d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(eb, path->slots[i]); 2013581c1760SQu Wenruo btrfs_node_key_to_cpu(eb, &first_key, path->slots[i]); 2014581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, ptr_gen, i - 1, 2015581c1760SQu Wenruo &first_key); 201664c043deSLiu Bo if (IS_ERR(eb)) { 201764c043deSLiu Bo return PTR_ERR(eb); 201864c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2019416bc658SJosef Bacik free_extent_buffer(eb); 2020416bc658SJosef Bacik return -EIO; 2021416bc658SJosef Bacik } 20225d4f98a2SYan Zheng BUG_ON(btrfs_header_level(eb) != i - 1); 20235d4f98a2SYan Zheng path->nodes[i - 1] = eb; 20245d4f98a2SYan Zheng path->slots[i - 1] = 0; 20255d4f98a2SYan Zheng } 20265d4f98a2SYan Zheng return 1; 20275d4f98a2SYan Zheng } 20285d4f98a2SYan Zheng 20295d4f98a2SYan Zheng /* 20305d4f98a2SYan Zheng * invalidate extent cache for file extents whose key in range of 20315d4f98a2SYan Zheng * [min_key, max_key) 20325d4f98a2SYan Zheng */ 20335d4f98a2SYan Zheng static int invalidate_extent_cache(struct btrfs_root *root, 20345d4f98a2SYan Zheng struct btrfs_key *min_key, 20355d4f98a2SYan Zheng struct btrfs_key *max_key) 20365d4f98a2SYan Zheng { 20370b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 20385d4f98a2SYan Zheng struct inode *inode = NULL; 20395d4f98a2SYan Zheng u64 objectid; 20405d4f98a2SYan Zheng u64 start, end; 204133345d01SLi Zefan u64 ino; 20425d4f98a2SYan Zheng 20435d4f98a2SYan Zheng objectid = min_key->objectid; 20445d4f98a2SYan Zheng while (1) { 20455d4f98a2SYan Zheng cond_resched(); 20465d4f98a2SYan Zheng iput(inode); 20475d4f98a2SYan Zheng 20485d4f98a2SYan Zheng if (objectid > max_key->objectid) 20495d4f98a2SYan Zheng break; 20505d4f98a2SYan Zheng 20515d4f98a2SYan Zheng inode = find_next_inode(root, objectid); 20525d4f98a2SYan Zheng if (!inode) 20535d4f98a2SYan Zheng break; 20544a0cc7caSNikolay Borisov ino = btrfs_ino(BTRFS_I(inode)); 20555d4f98a2SYan Zheng 205633345d01SLi Zefan if (ino > max_key->objectid) { 20575d4f98a2SYan Zheng iput(inode); 20585d4f98a2SYan Zheng break; 20595d4f98a2SYan Zheng } 20605d4f98a2SYan Zheng 206133345d01SLi Zefan objectid = ino + 1; 20625d4f98a2SYan Zheng if (!S_ISREG(inode->i_mode)) 20635d4f98a2SYan Zheng continue; 20645d4f98a2SYan Zheng 206533345d01SLi Zefan if (unlikely(min_key->objectid == ino)) { 20665d4f98a2SYan Zheng if (min_key->type > BTRFS_EXTENT_DATA_KEY) 20675d4f98a2SYan Zheng continue; 20685d4f98a2SYan Zheng if (min_key->type < BTRFS_EXTENT_DATA_KEY) 20695d4f98a2SYan Zheng start = 0; 20705d4f98a2SYan Zheng else { 20715d4f98a2SYan Zheng start = min_key->offset; 20720b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(start, fs_info->sectorsize)); 20735d4f98a2SYan Zheng } 20745d4f98a2SYan Zheng } else { 20755d4f98a2SYan Zheng start = 0; 20765d4f98a2SYan Zheng } 20775d4f98a2SYan Zheng 207833345d01SLi Zefan if (unlikely(max_key->objectid == ino)) { 20795d4f98a2SYan Zheng if (max_key->type < BTRFS_EXTENT_DATA_KEY) 20805d4f98a2SYan Zheng continue; 20815d4f98a2SYan Zheng if (max_key->type > BTRFS_EXTENT_DATA_KEY) { 20825d4f98a2SYan Zheng end = (u64)-1; 20835d4f98a2SYan Zheng } else { 20845d4f98a2SYan Zheng if (max_key->offset == 0) 20855d4f98a2SYan Zheng continue; 20865d4f98a2SYan Zheng end = max_key->offset; 20870b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 20885d4f98a2SYan Zheng end--; 20895d4f98a2SYan Zheng } 20905d4f98a2SYan Zheng } else { 20915d4f98a2SYan Zheng end = (u64)-1; 20925d4f98a2SYan Zheng } 20935d4f98a2SYan Zheng 20945d4f98a2SYan Zheng /* the lock_extent waits for readpage to complete */ 2095d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 2096dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 1); 2097d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 20985d4f98a2SYan Zheng } 20995d4f98a2SYan Zheng return 0; 21005d4f98a2SYan Zheng } 21015d4f98a2SYan Zheng 21025d4f98a2SYan Zheng static int find_next_key(struct btrfs_path *path, int level, 21035d4f98a2SYan Zheng struct btrfs_key *key) 21045d4f98a2SYan Zheng 21055d4f98a2SYan Zheng { 21065d4f98a2SYan Zheng while (level < BTRFS_MAX_LEVEL) { 21075d4f98a2SYan Zheng if (!path->nodes[level]) 21085d4f98a2SYan Zheng break; 21095d4f98a2SYan Zheng if (path->slots[level] + 1 < 21105d4f98a2SYan Zheng btrfs_header_nritems(path->nodes[level])) { 21115d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], key, 21125d4f98a2SYan Zheng path->slots[level] + 1); 21135d4f98a2SYan Zheng return 0; 21145d4f98a2SYan Zheng } 21155d4f98a2SYan Zheng level++; 21165d4f98a2SYan Zheng } 21175d4f98a2SYan Zheng return 1; 21185d4f98a2SYan Zheng } 21195d4f98a2SYan Zheng 21205d4f98a2SYan Zheng /* 2121d2311e69SQu Wenruo * Insert current subvolume into reloc_control::dirty_subvol_roots 2122d2311e69SQu Wenruo */ 2123d2311e69SQu Wenruo static void insert_dirty_subvol(struct btrfs_trans_handle *trans, 2124d2311e69SQu Wenruo struct reloc_control *rc, 2125d2311e69SQu Wenruo struct btrfs_root *root) 2126d2311e69SQu Wenruo { 2127d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2128d2311e69SQu Wenruo struct btrfs_root_item *reloc_root_item; 2129d2311e69SQu Wenruo 2130d2311e69SQu Wenruo /* @root must be a subvolume tree root with a valid reloc tree */ 2131d2311e69SQu Wenruo ASSERT(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 2132d2311e69SQu Wenruo ASSERT(reloc_root); 2133d2311e69SQu Wenruo 2134d2311e69SQu Wenruo reloc_root_item = &reloc_root->root_item; 2135d2311e69SQu Wenruo memset(&reloc_root_item->drop_progress, 0, 2136d2311e69SQu Wenruo sizeof(reloc_root_item->drop_progress)); 2137d2311e69SQu Wenruo reloc_root_item->drop_level = 0; 2138d2311e69SQu Wenruo btrfs_set_root_refs(reloc_root_item, 0); 2139d2311e69SQu Wenruo btrfs_update_reloc_root(trans, root); 2140d2311e69SQu Wenruo 2141d2311e69SQu Wenruo if (list_empty(&root->reloc_dirty_list)) { 214200246528SJosef Bacik btrfs_grab_root(root); 2143d2311e69SQu Wenruo list_add_tail(&root->reloc_dirty_list, &rc->dirty_subvol_roots); 2144d2311e69SQu Wenruo } 2145d2311e69SQu Wenruo } 2146d2311e69SQu Wenruo 2147d2311e69SQu Wenruo static int clean_dirty_subvols(struct reloc_control *rc) 2148d2311e69SQu Wenruo { 2149d2311e69SQu Wenruo struct btrfs_root *root; 2150d2311e69SQu Wenruo struct btrfs_root *next; 2151d2311e69SQu Wenruo int ret = 0; 215230d40577SQu Wenruo int ret2; 2153d2311e69SQu Wenruo 2154d2311e69SQu Wenruo list_for_each_entry_safe(root, next, &rc->dirty_subvol_roots, 2155d2311e69SQu Wenruo reloc_dirty_list) { 215630d40577SQu Wenruo if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 215730d40577SQu Wenruo /* Merged subvolume, cleanup its reloc root */ 2158d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2159d2311e69SQu Wenruo 2160d2311e69SQu Wenruo list_del_init(&root->reloc_dirty_list); 2161d2311e69SQu Wenruo root->reloc_root = NULL; 21626282675eSQu Wenruo /* 21636282675eSQu Wenruo * Need barrier to ensure clear_bit() only happens after 21646282675eSQu Wenruo * root->reloc_root = NULL. Pairs with have_reloc_root. 21656282675eSQu Wenruo */ 21666282675eSQu Wenruo smp_wmb(); 21671fac4a54SQu Wenruo clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 2168f28de8d8SJosef Bacik if (reloc_root) { 2169f44deb74SJosef Bacik /* 2170f44deb74SJosef Bacik * btrfs_drop_snapshot drops our ref we hold for 2171f44deb74SJosef Bacik * ->reloc_root. If it fails however we must 2172f44deb74SJosef Bacik * drop the ref ourselves. 2173f44deb74SJosef Bacik */ 2174f28de8d8SJosef Bacik ret2 = btrfs_drop_snapshot(reloc_root, 0, 1); 2175f44deb74SJosef Bacik if (ret2 < 0) { 2176f44deb74SJosef Bacik btrfs_put_root(reloc_root); 2177f44deb74SJosef Bacik if (!ret) 2178f28de8d8SJosef Bacik ret = ret2; 2179f28de8d8SJosef Bacik } 2180f44deb74SJosef Bacik } 218100246528SJosef Bacik btrfs_put_root(root); 218230d40577SQu Wenruo } else { 218330d40577SQu Wenruo /* Orphan reloc tree, just clean it up */ 21840078a9f9SNikolay Borisov ret2 = btrfs_drop_snapshot(root, 0, 1); 2185f44deb74SJosef Bacik if (ret2 < 0) { 2186f44deb74SJosef Bacik btrfs_put_root(root); 2187f44deb74SJosef Bacik if (!ret) 218830d40577SQu Wenruo ret = ret2; 218930d40577SQu Wenruo } 2190d2311e69SQu Wenruo } 2191f44deb74SJosef Bacik } 2192d2311e69SQu Wenruo return ret; 2193d2311e69SQu Wenruo } 2194d2311e69SQu Wenruo 2195d2311e69SQu Wenruo /* 21965d4f98a2SYan Zheng * merge the relocated tree blocks in reloc tree with corresponding 21975d4f98a2SYan Zheng * fs tree. 21985d4f98a2SYan Zheng */ 21995d4f98a2SYan Zheng static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, 22005d4f98a2SYan Zheng struct btrfs_root *root) 22015d4f98a2SYan Zheng { 22020b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 22035d4f98a2SYan Zheng struct btrfs_key key; 22045d4f98a2SYan Zheng struct btrfs_key next_key; 22059e6a0c52SJosef Bacik struct btrfs_trans_handle *trans = NULL; 22065d4f98a2SYan Zheng struct btrfs_root *reloc_root; 22075d4f98a2SYan Zheng struct btrfs_root_item *root_item; 22085d4f98a2SYan Zheng struct btrfs_path *path; 22093fd0a558SYan, Zheng struct extent_buffer *leaf; 22105d4f98a2SYan Zheng int level; 22115d4f98a2SYan Zheng int max_level; 22125d4f98a2SYan Zheng int replaced = 0; 22135d4f98a2SYan Zheng int ret; 22145d4f98a2SYan Zheng int err = 0; 22153fd0a558SYan, Zheng u32 min_reserved; 22165d4f98a2SYan Zheng 22175d4f98a2SYan Zheng path = btrfs_alloc_path(); 22185d4f98a2SYan Zheng if (!path) 22195d4f98a2SYan Zheng return -ENOMEM; 2220e4058b54SDavid Sterba path->reada = READA_FORWARD; 22215d4f98a2SYan Zheng 22225d4f98a2SYan Zheng reloc_root = root->reloc_root; 22235d4f98a2SYan Zheng root_item = &reloc_root->root_item; 22245d4f98a2SYan Zheng 22255d4f98a2SYan Zheng if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { 22265d4f98a2SYan Zheng level = btrfs_root_level(root_item); 222767439dadSDavid Sterba atomic_inc(&reloc_root->node->refs); 22285d4f98a2SYan Zheng path->nodes[level] = reloc_root->node; 22295d4f98a2SYan Zheng path->slots[level] = 0; 22305d4f98a2SYan Zheng } else { 22315d4f98a2SYan Zheng btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); 22325d4f98a2SYan Zheng 22335d4f98a2SYan Zheng level = root_item->drop_level; 22345d4f98a2SYan Zheng BUG_ON(level == 0); 22355d4f98a2SYan Zheng path->lowest_level = level; 22365d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); 223733c66f43SYan Zheng path->lowest_level = 0; 22385d4f98a2SYan Zheng if (ret < 0) { 22395d4f98a2SYan Zheng btrfs_free_path(path); 22405d4f98a2SYan Zheng return ret; 22415d4f98a2SYan Zheng } 22425d4f98a2SYan Zheng 22435d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &next_key, 22445d4f98a2SYan Zheng path->slots[level]); 22455d4f98a2SYan Zheng WARN_ON(memcmp(&key, &next_key, sizeof(key))); 22465d4f98a2SYan Zheng 22475d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 22485d4f98a2SYan Zheng } 22495d4f98a2SYan Zheng 22500b246afaSJeff Mahoney min_reserved = fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 22515d4f98a2SYan Zheng memset(&next_key, 0, sizeof(next_key)); 22525d4f98a2SYan Zheng 22535d4f98a2SYan Zheng while (1) { 225408e007d2SMiao Xie ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved, 225508e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 22563fd0a558SYan, Zheng if (ret) { 22579e6a0c52SJosef Bacik err = ret; 22589e6a0c52SJosef Bacik goto out; 22593fd0a558SYan, Zheng } 22609e6a0c52SJosef Bacik trans = btrfs_start_transaction(root, 0); 22619e6a0c52SJosef Bacik if (IS_ERR(trans)) { 22629e6a0c52SJosef Bacik err = PTR_ERR(trans); 22639e6a0c52SJosef Bacik trans = NULL; 22649e6a0c52SJosef Bacik goto out; 22659e6a0c52SJosef Bacik } 22662abc726aSJosef Bacik 22672abc726aSJosef Bacik /* 22682abc726aSJosef Bacik * At this point we no longer have a reloc_control, so we can't 22692abc726aSJosef Bacik * depend on btrfs_init_reloc_root to update our last_trans. 22702abc726aSJosef Bacik * 22712abc726aSJosef Bacik * But that's ok, we started the trans handle on our 22722abc726aSJosef Bacik * corresponding fs_root, which means it's been added to the 22732abc726aSJosef Bacik * dirty list. At commit time we'll still call 22742abc726aSJosef Bacik * btrfs_update_reloc_root() and update our root item 22752abc726aSJosef Bacik * appropriately. 22762abc726aSJosef Bacik */ 22772abc726aSJosef Bacik reloc_root->last_trans = trans->transid; 22789e6a0c52SJosef Bacik trans->block_rsv = rc->block_rsv; 22793fd0a558SYan, Zheng 22803fd0a558SYan, Zheng replaced = 0; 22815d4f98a2SYan Zheng max_level = level; 22825d4f98a2SYan Zheng 22835d4f98a2SYan Zheng ret = walk_down_reloc_tree(reloc_root, path, &level); 22845d4f98a2SYan Zheng if (ret < 0) { 22855d4f98a2SYan Zheng err = ret; 22865d4f98a2SYan Zheng goto out; 22875d4f98a2SYan Zheng } 22885d4f98a2SYan Zheng if (ret > 0) 22895d4f98a2SYan Zheng break; 22905d4f98a2SYan Zheng 22915d4f98a2SYan Zheng if (!find_next_key(path, level, &key) && 22925d4f98a2SYan Zheng btrfs_comp_cpu_keys(&next_key, &key) >= 0) { 22935d4f98a2SYan Zheng ret = 0; 22945d4f98a2SYan Zheng } else { 22953d0174f7SQu Wenruo ret = replace_path(trans, rc, root, reloc_root, path, 22963fd0a558SYan, Zheng &next_key, level, max_level); 22975d4f98a2SYan Zheng } 22985d4f98a2SYan Zheng if (ret < 0) { 22995d4f98a2SYan Zheng err = ret; 23005d4f98a2SYan Zheng goto out; 23015d4f98a2SYan Zheng } 23025d4f98a2SYan Zheng 23035d4f98a2SYan Zheng if (ret > 0) { 23045d4f98a2SYan Zheng level = ret; 23055d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 23065d4f98a2SYan Zheng path->slots[level]); 23075d4f98a2SYan Zheng replaced = 1; 23085d4f98a2SYan Zheng } 23095d4f98a2SYan Zheng 23105d4f98a2SYan Zheng ret = walk_up_reloc_tree(reloc_root, path, &level); 23115d4f98a2SYan Zheng if (ret > 0) 23125d4f98a2SYan Zheng break; 23135d4f98a2SYan Zheng 23145d4f98a2SYan Zheng BUG_ON(level == 0); 23155d4f98a2SYan Zheng /* 23165d4f98a2SYan Zheng * save the merging progress in the drop_progress. 23175d4f98a2SYan Zheng * this is OK since root refs == 1 in this case. 23185d4f98a2SYan Zheng */ 23195d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &root_item->drop_progress, 23205d4f98a2SYan Zheng path->slots[level]); 23215d4f98a2SYan Zheng root_item->drop_level = level; 23225d4f98a2SYan Zheng 23233a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 23249e6a0c52SJosef Bacik trans = NULL; 23255d4f98a2SYan Zheng 23262ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 23275d4f98a2SYan Zheng 23285d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 23295d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 23305d4f98a2SYan Zheng } 23315d4f98a2SYan Zheng 23325d4f98a2SYan Zheng /* 23335d4f98a2SYan Zheng * handle the case only one block in the fs tree need to be 23345d4f98a2SYan Zheng * relocated and the block is tree root. 23355d4f98a2SYan Zheng */ 23365d4f98a2SYan Zheng leaf = btrfs_lock_root_node(root); 23375d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); 23385d4f98a2SYan Zheng btrfs_tree_unlock(leaf); 23395d4f98a2SYan Zheng free_extent_buffer(leaf); 23405d4f98a2SYan Zheng if (ret < 0) 23415d4f98a2SYan Zheng err = ret; 23425d4f98a2SYan Zheng out: 23435d4f98a2SYan Zheng btrfs_free_path(path); 23445d4f98a2SYan Zheng 2345d2311e69SQu Wenruo if (err == 0) 2346d2311e69SQu Wenruo insert_dirty_subvol(trans, rc, root); 23475d4f98a2SYan Zheng 23489e6a0c52SJosef Bacik if (trans) 23493a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 23505d4f98a2SYan Zheng 23512ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 23525d4f98a2SYan Zheng 23535d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 23545d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 23555d4f98a2SYan Zheng 23565d4f98a2SYan Zheng return err; 23575d4f98a2SYan Zheng } 23585d4f98a2SYan Zheng 23593fd0a558SYan, Zheng static noinline_for_stack 23603fd0a558SYan, Zheng int prepare_to_merge(struct reloc_control *rc, int err) 23615d4f98a2SYan Zheng { 23623fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 23630b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 23643fd0a558SYan, Zheng struct btrfs_root *reloc_root; 23655d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 23663fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 23673fd0a558SYan, Zheng u64 num_bytes = 0; 23683fd0a558SYan, Zheng int ret; 23693fd0a558SYan, Zheng 23700b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 23710b246afaSJeff Mahoney rc->merging_rsv_size += fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 23723fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated * 2; 23730b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 23747585717fSChris Mason 23753fd0a558SYan, Zheng again: 23763fd0a558SYan, Zheng if (!err) { 23773fd0a558SYan, Zheng num_bytes = rc->merging_rsv_size; 237808e007d2SMiao Xie ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes, 237908e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 23803fd0a558SYan, Zheng if (ret) 23813fd0a558SYan, Zheng err = ret; 23823fd0a558SYan, Zheng } 23833fd0a558SYan, Zheng 23847a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 23853612b495STsutomu Itoh if (IS_ERR(trans)) { 23863612b495STsutomu Itoh if (!err) 23872ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 238863f018beSNikolay Borisov num_bytes, NULL); 23893612b495STsutomu Itoh return PTR_ERR(trans); 23903612b495STsutomu Itoh } 23913fd0a558SYan, Zheng 23923fd0a558SYan, Zheng if (!err) { 23933fd0a558SYan, Zheng if (num_bytes != rc->merging_rsv_size) { 23943a45bb20SJeff Mahoney btrfs_end_transaction(trans); 23952ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 239663f018beSNikolay Borisov num_bytes, NULL); 23973fd0a558SYan, Zheng goto again; 23983fd0a558SYan, Zheng } 23993fd0a558SYan, Zheng } 24003fd0a558SYan, Zheng 24013fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 24023fd0a558SYan, Zheng 24033fd0a558SYan, Zheng while (!list_empty(&rc->reloc_roots)) { 24043fd0a558SYan, Zheng reloc_root = list_entry(rc->reloc_roots.next, 24053fd0a558SYan, Zheng struct btrfs_root, root_list); 24063fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 24073fd0a558SYan, Zheng 24080b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 24093fd0a558SYan, Zheng BUG_ON(IS_ERR(root)); 24103fd0a558SYan, Zheng BUG_ON(root->reloc_root != reloc_root); 24113fd0a558SYan, Zheng 24123fd0a558SYan, Zheng /* 24133fd0a558SYan, Zheng * set reference count to 1, so btrfs_recover_relocation 24143fd0a558SYan, Zheng * knows it should resumes merging 24153fd0a558SYan, Zheng */ 24163fd0a558SYan, Zheng if (!err) 24173fd0a558SYan, Zheng btrfs_set_root_refs(&reloc_root->root_item, 1); 24183fd0a558SYan, Zheng btrfs_update_reloc_root(trans, root); 24193fd0a558SYan, Zheng 24203fd0a558SYan, Zheng list_add(&reloc_root->root_list, &reloc_roots); 242100246528SJosef Bacik btrfs_put_root(root); 24223fd0a558SYan, Zheng } 24233fd0a558SYan, Zheng 24243fd0a558SYan, Zheng list_splice(&reloc_roots, &rc->reloc_roots); 24253fd0a558SYan, Zheng 24263fd0a558SYan, Zheng if (!err) 24273a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 24283fd0a558SYan, Zheng else 24293a45bb20SJeff Mahoney btrfs_end_transaction(trans); 24303fd0a558SYan, Zheng return err; 24313fd0a558SYan, Zheng } 24323fd0a558SYan, Zheng 24333fd0a558SYan, Zheng static noinline_for_stack 2434aca1bba6SLiu Bo void free_reloc_roots(struct list_head *list) 2435aca1bba6SLiu Bo { 2436aca1bba6SLiu Bo struct btrfs_root *reloc_root; 2437aca1bba6SLiu Bo 2438aca1bba6SLiu Bo while (!list_empty(list)) { 2439aca1bba6SLiu Bo reloc_root = list_entry(list->next, struct btrfs_root, 2440aca1bba6SLiu Bo root_list); 2441bb166d72SNaohiro Aota __del_reloc_root(reloc_root); 2442aca1bba6SLiu Bo } 2443aca1bba6SLiu Bo } 2444aca1bba6SLiu Bo 2445aca1bba6SLiu Bo static noinline_for_stack 244694404e82SDavid Sterba void merge_reloc_roots(struct reloc_control *rc) 24473fd0a558SYan, Zheng { 24480b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 24495d4f98a2SYan Zheng struct btrfs_root *root; 24505d4f98a2SYan Zheng struct btrfs_root *reloc_root; 24513fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 24523fd0a558SYan, Zheng int found = 0; 2453aca1bba6SLiu Bo int ret = 0; 24543fd0a558SYan, Zheng again: 24553fd0a558SYan, Zheng root = rc->extent_root; 24567585717fSChris Mason 24577585717fSChris Mason /* 24587585717fSChris Mason * this serializes us with btrfs_record_root_in_transaction, 24597585717fSChris Mason * we have to make sure nobody is in the middle of 24607585717fSChris Mason * adding their roots to the list while we are 24617585717fSChris Mason * doing this splice 24627585717fSChris Mason */ 24630b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 24643fd0a558SYan, Zheng list_splice_init(&rc->reloc_roots, &reloc_roots); 24650b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 24665d4f98a2SYan Zheng 24673fd0a558SYan, Zheng while (!list_empty(&reloc_roots)) { 24683fd0a558SYan, Zheng found = 1; 24693fd0a558SYan, Zheng reloc_root = list_entry(reloc_roots.next, 24703fd0a558SYan, Zheng struct btrfs_root, root_list); 24715d4f98a2SYan Zheng 24725d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 24730b246afaSJeff Mahoney root = read_fs_root(fs_info, 24745d4f98a2SYan Zheng reloc_root->root_key.offset); 24755d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 24765d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 24775d4f98a2SYan Zheng 24783fd0a558SYan, Zheng ret = merge_reloc_root(rc, root); 247900246528SJosef Bacik btrfs_put_root(root); 2480b37b39cdSJosef Bacik if (ret) { 248125e293c2SWang Shilong if (list_empty(&reloc_root->root_list)) 248225e293c2SWang Shilong list_add_tail(&reloc_root->root_list, 248325e293c2SWang Shilong &reloc_roots); 2484aca1bba6SLiu Bo goto out; 2485b37b39cdSJosef Bacik } 24863fd0a558SYan, Zheng } else { 24873fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 248830d40577SQu Wenruo /* Don't forget to queue this reloc root for cleanup */ 248930d40577SQu Wenruo list_add_tail(&reloc_root->reloc_dirty_list, 249030d40577SQu Wenruo &rc->dirty_subvol_roots); 24913fd0a558SYan, Zheng } 24925d4f98a2SYan Zheng } 24935d4f98a2SYan Zheng 24943fd0a558SYan, Zheng if (found) { 24953fd0a558SYan, Zheng found = 0; 24963fd0a558SYan, Zheng goto again; 24975d4f98a2SYan Zheng } 2498aca1bba6SLiu Bo out: 2499aca1bba6SLiu Bo if (ret) { 25000b246afaSJeff Mahoney btrfs_handle_fs_error(fs_info, ret, NULL); 2501aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 2502aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 2503467bb1d2SWang Shilong 2504467bb1d2SWang Shilong /* new reloc root may be added */ 25050b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 2506467bb1d2SWang Shilong list_splice_init(&rc->reloc_roots, &reloc_roots); 25070b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 2508467bb1d2SWang Shilong if (!list_empty(&reloc_roots)) 2509467bb1d2SWang Shilong free_reloc_roots(&reloc_roots); 2510aca1bba6SLiu Bo } 2511aca1bba6SLiu Bo 25127b7b7431SJosef Bacik /* 25137b7b7431SJosef Bacik * We used to have 25147b7b7431SJosef Bacik * 25157b7b7431SJosef Bacik * BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); 25167b7b7431SJosef Bacik * 25177b7b7431SJosef Bacik * here, but it's wrong. If we fail to start the transaction in 25187b7b7431SJosef Bacik * prepare_to_merge() we will have only 0 ref reloc roots, none of which 25197b7b7431SJosef Bacik * have actually been removed from the reloc_root_tree rb tree. This is 25207b7b7431SJosef Bacik * fine because we're bailing here, and we hold a reference on the root 25217b7b7431SJosef Bacik * for the list that holds it, so these roots will be cleaned up when we 25227b7b7431SJosef Bacik * do the reloc_dirty_list afterwards. Meanwhile the root->reloc_root 25237b7b7431SJosef Bacik * will be cleaned up on unmount. 25247b7b7431SJosef Bacik * 25257b7b7431SJosef Bacik * The remaining nodes will be cleaned up by free_reloc_control. 25267b7b7431SJosef Bacik */ 25275d4f98a2SYan Zheng } 25285d4f98a2SYan Zheng 25295d4f98a2SYan Zheng static void free_block_list(struct rb_root *blocks) 25305d4f98a2SYan Zheng { 25315d4f98a2SYan Zheng struct tree_block *block; 25325d4f98a2SYan Zheng struct rb_node *rb_node; 25335d4f98a2SYan Zheng while ((rb_node = rb_first(blocks))) { 25345d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 25355d4f98a2SYan Zheng rb_erase(rb_node, blocks); 25365d4f98a2SYan Zheng kfree(block); 25375d4f98a2SYan Zheng } 25385d4f98a2SYan Zheng } 25395d4f98a2SYan Zheng 25405d4f98a2SYan Zheng static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, 25415d4f98a2SYan Zheng struct btrfs_root *reloc_root) 25425d4f98a2SYan Zheng { 25430b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = reloc_root->fs_info; 25445d4f98a2SYan Zheng struct btrfs_root *root; 2545442b1ac5SJosef Bacik int ret; 25465d4f98a2SYan Zheng 25475d4f98a2SYan Zheng if (reloc_root->last_trans == trans->transid) 25485d4f98a2SYan Zheng return 0; 25495d4f98a2SYan Zheng 25500b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 25515d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 25525d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 2553442b1ac5SJosef Bacik ret = btrfs_record_root_in_trans(trans, root); 255400246528SJosef Bacik btrfs_put_root(root); 25555d4f98a2SYan Zheng 2556442b1ac5SJosef Bacik return ret; 25575d4f98a2SYan Zheng } 25585d4f98a2SYan Zheng 25593fd0a558SYan, Zheng static noinline_for_stack 25603fd0a558SYan, Zheng struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, 25613fd0a558SYan, Zheng struct reloc_control *rc, 2562a26195a5SQu Wenruo struct btrfs_backref_node *node, 2563a26195a5SQu Wenruo struct btrfs_backref_edge *edges[]) 25645d4f98a2SYan Zheng { 2565a26195a5SQu Wenruo struct btrfs_backref_node *next; 25665d4f98a2SYan Zheng struct btrfs_root *root; 25673fd0a558SYan, Zheng int index = 0; 25683fd0a558SYan, Zheng 25695d4f98a2SYan Zheng next = node; 25705d4f98a2SYan Zheng while (1) { 25715d4f98a2SYan Zheng cond_resched(); 25725d4f98a2SYan Zheng next = walk_up_backref(next, edges, &index); 25735d4f98a2SYan Zheng root = next->root; 25743fd0a558SYan, Zheng BUG_ON(!root); 257527cdeb70SMiao Xie BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS, &root->state)); 25765d4f98a2SYan Zheng 25775d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { 25785d4f98a2SYan Zheng record_reloc_root_in_trans(trans, root); 25795d4f98a2SYan Zheng break; 25805d4f98a2SYan Zheng } 25815d4f98a2SYan Zheng 25825d4f98a2SYan Zheng btrfs_record_root_in_trans(trans, root); 25833fd0a558SYan, Zheng root = root->reloc_root; 25843fd0a558SYan, Zheng 25853fd0a558SYan, Zheng if (next->new_bytenr != root->node->start) { 25863fd0a558SYan, Zheng BUG_ON(next->new_bytenr); 25873fd0a558SYan, Zheng BUG_ON(!list_empty(&next->list)); 25883fd0a558SYan, Zheng next->new_bytenr = root->node->start; 258900246528SJosef Bacik btrfs_put_root(next->root); 259000246528SJosef Bacik next->root = btrfs_grab_root(root); 25910b530bc5SJosef Bacik ASSERT(next->root); 25923fd0a558SYan, Zheng list_add_tail(&next->list, 25933fd0a558SYan, Zheng &rc->backref_cache.changed); 25949569cc20SQu Wenruo mark_block_processed(rc, next); 25955d4f98a2SYan Zheng break; 25965d4f98a2SYan Zheng } 25975d4f98a2SYan Zheng 25983fd0a558SYan, Zheng WARN_ON(1); 25995d4f98a2SYan Zheng root = NULL; 26005d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 26015d4f98a2SYan Zheng if (!next || next->level <= node->level) 26025d4f98a2SYan Zheng break; 26035d4f98a2SYan Zheng } 26043fd0a558SYan, Zheng if (!root) 26053fd0a558SYan, Zheng return NULL; 26065d4f98a2SYan Zheng 26073fd0a558SYan, Zheng next = node; 26083fd0a558SYan, Zheng /* setup backref node path for btrfs_reloc_cow_block */ 26093fd0a558SYan, Zheng while (1) { 26103fd0a558SYan, Zheng rc->backref_cache.path[next->level] = next; 26113fd0a558SYan, Zheng if (--index < 0) 26123fd0a558SYan, Zheng break; 26133fd0a558SYan, Zheng next = edges[index]->node[UPPER]; 26143fd0a558SYan, Zheng } 26155d4f98a2SYan Zheng return root; 26165d4f98a2SYan Zheng } 26175d4f98a2SYan Zheng 26183fd0a558SYan, Zheng /* 26193fd0a558SYan, Zheng * select a tree root for relocation. return NULL if the block 26203fd0a558SYan, Zheng * is reference counted. we should use do_relocation() in this 26213fd0a558SYan, Zheng * case. return a tree root pointer if the block isn't reference 26223fd0a558SYan, Zheng * counted. return -ENOENT if the block is root of reloc tree. 26233fd0a558SYan, Zheng */ 26245d4f98a2SYan Zheng static noinline_for_stack 2625a26195a5SQu Wenruo struct btrfs_root *select_one_root(struct btrfs_backref_node *node) 26265d4f98a2SYan Zheng { 2627a26195a5SQu Wenruo struct btrfs_backref_node *next; 26283fd0a558SYan, Zheng struct btrfs_root *root; 26293fd0a558SYan, Zheng struct btrfs_root *fs_root = NULL; 2630a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 26313fd0a558SYan, Zheng int index = 0; 26323fd0a558SYan, Zheng 26333fd0a558SYan, Zheng next = node; 26343fd0a558SYan, Zheng while (1) { 26353fd0a558SYan, Zheng cond_resched(); 26363fd0a558SYan, Zheng next = walk_up_backref(next, edges, &index); 26373fd0a558SYan, Zheng root = next->root; 26383fd0a558SYan, Zheng BUG_ON(!root); 26393fd0a558SYan, Zheng 264025985edcSLucas De Marchi /* no other choice for non-references counted tree */ 264127cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 26423fd0a558SYan, Zheng return root; 26433fd0a558SYan, Zheng 26443fd0a558SYan, Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) 26453fd0a558SYan, Zheng fs_root = root; 26463fd0a558SYan, Zheng 26473fd0a558SYan, Zheng if (next != node) 26483fd0a558SYan, Zheng return NULL; 26493fd0a558SYan, Zheng 26503fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 26513fd0a558SYan, Zheng if (!next || next->level <= node->level) 26523fd0a558SYan, Zheng break; 26533fd0a558SYan, Zheng } 26543fd0a558SYan, Zheng 26553fd0a558SYan, Zheng if (!fs_root) 26563fd0a558SYan, Zheng return ERR_PTR(-ENOENT); 26573fd0a558SYan, Zheng return fs_root; 26585d4f98a2SYan Zheng } 26595d4f98a2SYan Zheng 26605d4f98a2SYan Zheng static noinline_for_stack 26613fd0a558SYan, Zheng u64 calcu_metadata_size(struct reloc_control *rc, 2662a26195a5SQu Wenruo struct btrfs_backref_node *node, int reserve) 26635d4f98a2SYan Zheng { 26640b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 2665a26195a5SQu Wenruo struct btrfs_backref_node *next = node; 2666a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2667a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 26683fd0a558SYan, Zheng u64 num_bytes = 0; 26693fd0a558SYan, Zheng int index = 0; 26705d4f98a2SYan Zheng 26713fd0a558SYan, Zheng BUG_ON(reserve && node->processed); 26723fd0a558SYan, Zheng 26733fd0a558SYan, Zheng while (next) { 26743fd0a558SYan, Zheng cond_resched(); 26755d4f98a2SYan Zheng while (1) { 26763fd0a558SYan, Zheng if (next->processed && (reserve || next != node)) 26775d4f98a2SYan Zheng break; 26785d4f98a2SYan Zheng 26790b246afaSJeff Mahoney num_bytes += fs_info->nodesize; 26803fd0a558SYan, Zheng 26813fd0a558SYan, Zheng if (list_empty(&next->upper)) 26823fd0a558SYan, Zheng break; 26833fd0a558SYan, Zheng 26843fd0a558SYan, Zheng edge = list_entry(next->upper.next, 2685a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 26863fd0a558SYan, Zheng edges[index++] = edge; 26873fd0a558SYan, Zheng next = edge->node[UPPER]; 26885d4f98a2SYan Zheng } 26893fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 26903fd0a558SYan, Zheng } 26913fd0a558SYan, Zheng return num_bytes; 26923fd0a558SYan, Zheng } 26933fd0a558SYan, Zheng 26943fd0a558SYan, Zheng static int reserve_metadata_space(struct btrfs_trans_handle *trans, 26953fd0a558SYan, Zheng struct reloc_control *rc, 2696a26195a5SQu Wenruo struct btrfs_backref_node *node) 26973fd0a558SYan, Zheng { 26983fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 2699da17066cSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 27003fd0a558SYan, Zheng u64 num_bytes; 27013fd0a558SYan, Zheng int ret; 27020647bf56SWang Shilong u64 tmp; 27033fd0a558SYan, Zheng 27043fd0a558SYan, Zheng num_bytes = calcu_metadata_size(rc, node, 1) * 2; 27053fd0a558SYan, Zheng 27063fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 27070647bf56SWang Shilong rc->reserved_bytes += num_bytes; 27088ca17f0fSJosef Bacik 27098ca17f0fSJosef Bacik /* 27108ca17f0fSJosef Bacik * We are under a transaction here so we can only do limited flushing. 27118ca17f0fSJosef Bacik * If we get an enospc just kick back -EAGAIN so we know to drop the 27128ca17f0fSJosef Bacik * transaction and try to refill when we can flush all the things. 27138ca17f0fSJosef Bacik */ 27140647bf56SWang Shilong ret = btrfs_block_rsv_refill(root, rc->block_rsv, num_bytes, 27158ca17f0fSJosef Bacik BTRFS_RESERVE_FLUSH_LIMIT); 27163fd0a558SYan, Zheng if (ret) { 2717da17066cSJeff Mahoney tmp = fs_info->nodesize * RELOCATION_RESERVED_NODES; 27180647bf56SWang Shilong while (tmp <= rc->reserved_bytes) 27190647bf56SWang Shilong tmp <<= 1; 27200647bf56SWang Shilong /* 27210647bf56SWang Shilong * only one thread can access block_rsv at this point, 27220647bf56SWang Shilong * so we don't need hold lock to protect block_rsv. 27230647bf56SWang Shilong * we expand more reservation size here to allow enough 272452042d8eSAndrea Gelmini * space for relocation and we will return earlier in 27250647bf56SWang Shilong * enospc case. 27260647bf56SWang Shilong */ 2727da17066cSJeff Mahoney rc->block_rsv->size = tmp + fs_info->nodesize * 27280647bf56SWang Shilong RELOCATION_RESERVED_NODES; 27298ca17f0fSJosef Bacik return -EAGAIN; 27303fd0a558SYan, Zheng } 27313fd0a558SYan, Zheng 27323fd0a558SYan, Zheng return 0; 27333fd0a558SYan, Zheng } 27343fd0a558SYan, Zheng 27355d4f98a2SYan Zheng /* 27365d4f98a2SYan Zheng * relocate a block tree, and then update pointers in upper level 27375d4f98a2SYan Zheng * blocks that reference the block to point to the new location. 27385d4f98a2SYan Zheng * 27395d4f98a2SYan Zheng * if called by link_to_upper, the block has already been relocated. 27405d4f98a2SYan Zheng * in that case this function just updates pointers. 27415d4f98a2SYan Zheng */ 27425d4f98a2SYan Zheng static int do_relocation(struct btrfs_trans_handle *trans, 27433fd0a558SYan, Zheng struct reloc_control *rc, 2744a26195a5SQu Wenruo struct btrfs_backref_node *node, 27455d4f98a2SYan Zheng struct btrfs_key *key, 27465d4f98a2SYan Zheng struct btrfs_path *path, int lowest) 27475d4f98a2SYan Zheng { 27482ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 2749a26195a5SQu Wenruo struct btrfs_backref_node *upper; 2750a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2751a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 27525d4f98a2SYan Zheng struct btrfs_root *root; 27535d4f98a2SYan Zheng struct extent_buffer *eb; 27545d4f98a2SYan Zheng u32 blocksize; 27555d4f98a2SYan Zheng u64 bytenr; 27565d4f98a2SYan Zheng u64 generation; 27575d4f98a2SYan Zheng int slot; 27585d4f98a2SYan Zheng int ret; 27595d4f98a2SYan Zheng int err = 0; 27605d4f98a2SYan Zheng 27615d4f98a2SYan Zheng BUG_ON(lowest && node->eb); 27625d4f98a2SYan Zheng 27635d4f98a2SYan Zheng path->lowest_level = node->level + 1; 27643fd0a558SYan, Zheng rc->backref_cache.path[node->level] = node; 27655d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) { 2766581c1760SQu Wenruo struct btrfs_key first_key; 276782fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 2768581c1760SQu Wenruo 27695d4f98a2SYan Zheng cond_resched(); 27705d4f98a2SYan Zheng 27715d4f98a2SYan Zheng upper = edge->node[UPPER]; 2772dc4103f9SWang Shilong root = select_reloc_root(trans, rc, upper, edges); 27733fd0a558SYan, Zheng BUG_ON(!root); 27745d4f98a2SYan Zheng 27753fd0a558SYan, Zheng if (upper->eb && !upper->locked) { 27763fd0a558SYan, Zheng if (!lowest) { 27773fd0a558SYan, Zheng ret = btrfs_bin_search(upper->eb, key, 27783fd0a558SYan, Zheng upper->level, &slot); 2779cbca7d59SFilipe Manana if (ret < 0) { 2780cbca7d59SFilipe Manana err = ret; 2781cbca7d59SFilipe Manana goto next; 2782cbca7d59SFilipe Manana } 27833fd0a558SYan, Zheng BUG_ON(ret); 27843fd0a558SYan, Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 27853fd0a558SYan, Zheng if (node->eb->start == bytenr) 27863fd0a558SYan, Zheng goto next; 27873fd0a558SYan, Zheng } 2788b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(upper); 27893fd0a558SYan, Zheng } 27905d4f98a2SYan Zheng 27915d4f98a2SYan Zheng if (!upper->eb) { 27925d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 27933561b9dbSLiu Bo if (ret) { 27943561b9dbSLiu Bo if (ret < 0) 27955d4f98a2SYan Zheng err = ret; 27963561b9dbSLiu Bo else 27973561b9dbSLiu Bo err = -ENOENT; 27983561b9dbSLiu Bo 27993561b9dbSLiu Bo btrfs_release_path(path); 28005d4f98a2SYan Zheng break; 28015d4f98a2SYan Zheng } 28025d4f98a2SYan Zheng 28033fd0a558SYan, Zheng if (!upper->eb) { 28043fd0a558SYan, Zheng upper->eb = path->nodes[upper->level]; 28053fd0a558SYan, Zheng path->nodes[upper->level] = NULL; 28063fd0a558SYan, Zheng } else { 28073fd0a558SYan, Zheng BUG_ON(upper->eb != path->nodes[upper->level]); 28083fd0a558SYan, Zheng } 28093fd0a558SYan, Zheng 28103fd0a558SYan, Zheng upper->locked = 1; 28113fd0a558SYan, Zheng path->locks[upper->level] = 0; 28123fd0a558SYan, Zheng 28135d4f98a2SYan Zheng slot = path->slots[upper->level]; 2814b3b4aa74SDavid Sterba btrfs_release_path(path); 28155d4f98a2SYan Zheng } else { 28165d4f98a2SYan Zheng ret = btrfs_bin_search(upper->eb, key, upper->level, 28175d4f98a2SYan Zheng &slot); 2818cbca7d59SFilipe Manana if (ret < 0) { 2819cbca7d59SFilipe Manana err = ret; 2820cbca7d59SFilipe Manana goto next; 2821cbca7d59SFilipe Manana } 28225d4f98a2SYan Zheng BUG_ON(ret); 28235d4f98a2SYan Zheng } 28245d4f98a2SYan Zheng 28255d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 28263fd0a558SYan, Zheng if (lowest) { 28274547f4d8SLiu Bo if (bytenr != node->bytenr) { 28284547f4d8SLiu Bo btrfs_err(root->fs_info, 28294547f4d8SLiu Bo "lowest leaf/node mismatch: bytenr %llu node->bytenr %llu slot %d upper %llu", 28304547f4d8SLiu Bo bytenr, node->bytenr, slot, 28314547f4d8SLiu Bo upper->eb->start); 28324547f4d8SLiu Bo err = -EIO; 28334547f4d8SLiu Bo goto next; 28344547f4d8SLiu Bo } 28355d4f98a2SYan Zheng } else { 28363fd0a558SYan, Zheng if (node->eb->start == bytenr) 28373fd0a558SYan, Zheng goto next; 28385d4f98a2SYan Zheng } 28395d4f98a2SYan Zheng 2840da17066cSJeff Mahoney blocksize = root->fs_info->nodesize; 28415d4f98a2SYan Zheng generation = btrfs_node_ptr_generation(upper->eb, slot); 2842581c1760SQu Wenruo btrfs_node_key_to_cpu(upper->eb, &first_key, slot); 2843581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, generation, 2844581c1760SQu Wenruo upper->level - 1, &first_key); 284564c043deSLiu Bo if (IS_ERR(eb)) { 284664c043deSLiu Bo err = PTR_ERR(eb); 284764c043deSLiu Bo goto next; 284864c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2849416bc658SJosef Bacik free_extent_buffer(eb); 285097d9a8a4STsutomu Itoh err = -EIO; 285197d9a8a4STsutomu Itoh goto next; 285297d9a8a4STsutomu Itoh } 28535d4f98a2SYan Zheng btrfs_tree_lock(eb); 28548bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 28555d4f98a2SYan Zheng 28565d4f98a2SYan Zheng if (!node->eb) { 28575d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, eb, upper->eb, 28585d4f98a2SYan Zheng slot, &eb); 28593fd0a558SYan, Zheng btrfs_tree_unlock(eb); 28603fd0a558SYan, Zheng free_extent_buffer(eb); 28615d4f98a2SYan Zheng if (ret < 0) { 28625d4f98a2SYan Zheng err = ret; 28633fd0a558SYan, Zheng goto next; 28645d4f98a2SYan Zheng } 28653fd0a558SYan, Zheng BUG_ON(node->eb != eb); 28665d4f98a2SYan Zheng } else { 28675d4f98a2SYan Zheng btrfs_set_node_blockptr(upper->eb, slot, 28685d4f98a2SYan Zheng node->eb->start); 28695d4f98a2SYan Zheng btrfs_set_node_ptr_generation(upper->eb, slot, 28705d4f98a2SYan Zheng trans->transid); 28715d4f98a2SYan Zheng btrfs_mark_buffer_dirty(upper->eb); 28725d4f98a2SYan Zheng 287382fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, 28745d4f98a2SYan Zheng node->eb->start, blocksize, 287582fa113fSQu Wenruo upper->eb->start); 287682fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 287782fa113fSQu Wenruo btrfs_init_tree_ref(&ref, node->level, 287882fa113fSQu Wenruo btrfs_header_owner(upper->eb)); 287982fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 28805d4f98a2SYan Zheng BUG_ON(ret); 28815d4f98a2SYan Zheng 28825d4f98a2SYan Zheng ret = btrfs_drop_subtree(trans, root, eb, upper->eb); 28835d4f98a2SYan Zheng BUG_ON(ret); 28845d4f98a2SYan Zheng } 28853fd0a558SYan, Zheng next: 28863fd0a558SYan, Zheng if (!upper->pending) 2887b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(upper); 28883fd0a558SYan, Zheng else 2889b0fe7078SQu Wenruo btrfs_backref_unlock_node_buffer(upper); 28903fd0a558SYan, Zheng if (err) 28913fd0a558SYan, Zheng break; 28925d4f98a2SYan Zheng } 28933fd0a558SYan, Zheng 28943fd0a558SYan, Zheng if (!err && node->pending) { 2895b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(node); 28963fd0a558SYan, Zheng list_move_tail(&node->list, &rc->backref_cache.changed); 28973fd0a558SYan, Zheng node->pending = 0; 28985d4f98a2SYan Zheng } 28993fd0a558SYan, Zheng 29005d4f98a2SYan Zheng path->lowest_level = 0; 29013fd0a558SYan, Zheng BUG_ON(err == -ENOSPC); 29025d4f98a2SYan Zheng return err; 29035d4f98a2SYan Zheng } 29045d4f98a2SYan Zheng 29055d4f98a2SYan Zheng static int link_to_upper(struct btrfs_trans_handle *trans, 29063fd0a558SYan, Zheng struct reloc_control *rc, 2907a26195a5SQu Wenruo struct btrfs_backref_node *node, 29085d4f98a2SYan Zheng struct btrfs_path *path) 29095d4f98a2SYan Zheng { 29105d4f98a2SYan Zheng struct btrfs_key key; 29115d4f98a2SYan Zheng 29125d4f98a2SYan Zheng btrfs_node_key_to_cpu(node->eb, &key, 0); 29133fd0a558SYan, Zheng return do_relocation(trans, rc, node, &key, path, 0); 29145d4f98a2SYan Zheng } 29155d4f98a2SYan Zheng 29165d4f98a2SYan Zheng static int finish_pending_nodes(struct btrfs_trans_handle *trans, 29173fd0a558SYan, Zheng struct reloc_control *rc, 29183fd0a558SYan, Zheng struct btrfs_path *path, int err) 29195d4f98a2SYan Zheng { 29203fd0a558SYan, Zheng LIST_HEAD(list); 2921a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 2922a26195a5SQu Wenruo struct btrfs_backref_node *node; 29235d4f98a2SYan Zheng int level; 29245d4f98a2SYan Zheng int ret; 29255d4f98a2SYan Zheng 29265d4f98a2SYan Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 29275d4f98a2SYan Zheng while (!list_empty(&cache->pending[level])) { 29285d4f98a2SYan Zheng node = list_entry(cache->pending[level].next, 2929a26195a5SQu Wenruo struct btrfs_backref_node, list); 29303fd0a558SYan, Zheng list_move_tail(&node->list, &list); 29313fd0a558SYan, Zheng BUG_ON(!node->pending); 29325d4f98a2SYan Zheng 29333fd0a558SYan, Zheng if (!err) { 29343fd0a558SYan, Zheng ret = link_to_upper(trans, rc, node, path); 29355d4f98a2SYan Zheng if (ret < 0) 29365d4f98a2SYan Zheng err = ret; 29375d4f98a2SYan Zheng } 29385d4f98a2SYan Zheng } 29393fd0a558SYan, Zheng list_splice_init(&list, &cache->pending[level]); 29403fd0a558SYan, Zheng } 29415d4f98a2SYan Zheng return err; 29425d4f98a2SYan Zheng } 29435d4f98a2SYan Zheng 29445d4f98a2SYan Zheng /* 29455d4f98a2SYan Zheng * mark a block and all blocks directly/indirectly reference the block 29465d4f98a2SYan Zheng * as processed. 29475d4f98a2SYan Zheng */ 29485d4f98a2SYan Zheng static void update_processed_blocks(struct reloc_control *rc, 2949a26195a5SQu Wenruo struct btrfs_backref_node *node) 29505d4f98a2SYan Zheng { 2951a26195a5SQu Wenruo struct btrfs_backref_node *next = node; 2952a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2953a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 29545d4f98a2SYan Zheng int index = 0; 29555d4f98a2SYan Zheng 29565d4f98a2SYan Zheng while (next) { 29575d4f98a2SYan Zheng cond_resched(); 29585d4f98a2SYan Zheng while (1) { 29595d4f98a2SYan Zheng if (next->processed) 29605d4f98a2SYan Zheng break; 29615d4f98a2SYan Zheng 29629569cc20SQu Wenruo mark_block_processed(rc, next); 29635d4f98a2SYan Zheng 29645d4f98a2SYan Zheng if (list_empty(&next->upper)) 29655d4f98a2SYan Zheng break; 29665d4f98a2SYan Zheng 29675d4f98a2SYan Zheng edge = list_entry(next->upper.next, 2968a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 29695d4f98a2SYan Zheng edges[index++] = edge; 29705d4f98a2SYan Zheng next = edge->node[UPPER]; 29715d4f98a2SYan Zheng } 29725d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 29735d4f98a2SYan Zheng } 29745d4f98a2SYan Zheng } 29755d4f98a2SYan Zheng 29767476dfdaSDavid Sterba static int tree_block_processed(u64 bytenr, struct reloc_control *rc) 29775d4f98a2SYan Zheng { 2978da17066cSJeff Mahoney u32 blocksize = rc->extent_root->fs_info->nodesize; 29797476dfdaSDavid Sterba 29805d4f98a2SYan Zheng if (test_range_bit(&rc->processed_blocks, bytenr, 29819655d298SChris Mason bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) 29825d4f98a2SYan Zheng return 1; 29835d4f98a2SYan Zheng return 0; 29845d4f98a2SYan Zheng } 29855d4f98a2SYan Zheng 29862ff7e61eSJeff Mahoney static int get_tree_block_key(struct btrfs_fs_info *fs_info, 29875d4f98a2SYan Zheng struct tree_block *block) 29885d4f98a2SYan Zheng { 29895d4f98a2SYan Zheng struct extent_buffer *eb; 29905d4f98a2SYan Zheng 2991581c1760SQu Wenruo eb = read_tree_block(fs_info, block->bytenr, block->key.offset, 2992581c1760SQu Wenruo block->level, NULL); 299364c043deSLiu Bo if (IS_ERR(eb)) { 299464c043deSLiu Bo return PTR_ERR(eb); 299564c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2996416bc658SJosef Bacik free_extent_buffer(eb); 2997416bc658SJosef Bacik return -EIO; 2998416bc658SJosef Bacik } 29995d4f98a2SYan Zheng if (block->level == 0) 30005d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &block->key, 0); 30015d4f98a2SYan Zheng else 30025d4f98a2SYan Zheng btrfs_node_key_to_cpu(eb, &block->key, 0); 30035d4f98a2SYan Zheng free_extent_buffer(eb); 30045d4f98a2SYan Zheng block->key_ready = 1; 30055d4f98a2SYan Zheng return 0; 30065d4f98a2SYan Zheng } 30075d4f98a2SYan Zheng 30085d4f98a2SYan Zheng /* 30095d4f98a2SYan Zheng * helper function to relocate a tree block 30105d4f98a2SYan Zheng */ 30115d4f98a2SYan Zheng static int relocate_tree_block(struct btrfs_trans_handle *trans, 30125d4f98a2SYan Zheng struct reloc_control *rc, 3013a26195a5SQu Wenruo struct btrfs_backref_node *node, 30145d4f98a2SYan Zheng struct btrfs_key *key, 30155d4f98a2SYan Zheng struct btrfs_path *path) 30165d4f98a2SYan Zheng { 30175d4f98a2SYan Zheng struct btrfs_root *root; 30183fd0a558SYan, Zheng int ret = 0; 30195d4f98a2SYan Zheng 30203fd0a558SYan, Zheng if (!node) 30215d4f98a2SYan Zheng return 0; 30223fd0a558SYan, Zheng 30235f6b2e5cSJosef Bacik /* 30245f6b2e5cSJosef Bacik * If we fail here we want to drop our backref_node because we are going 30255f6b2e5cSJosef Bacik * to start over and regenerate the tree for it. 30265f6b2e5cSJosef Bacik */ 30275f6b2e5cSJosef Bacik ret = reserve_metadata_space(trans, rc, node); 30285f6b2e5cSJosef Bacik if (ret) 30295f6b2e5cSJosef Bacik goto out; 30305f6b2e5cSJosef Bacik 30313fd0a558SYan, Zheng BUG_ON(node->processed); 3032147d256eSZhaolei root = select_one_root(node); 30333fd0a558SYan, Zheng if (root == ERR_PTR(-ENOENT)) { 30343fd0a558SYan, Zheng update_processed_blocks(rc, node); 30353fd0a558SYan, Zheng goto out; 30365d4f98a2SYan Zheng } 30375d4f98a2SYan Zheng 30383fd0a558SYan, Zheng if (root) { 303927cdeb70SMiao Xie if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) { 30403fd0a558SYan, Zheng BUG_ON(node->new_bytenr); 30413fd0a558SYan, Zheng BUG_ON(!list_empty(&node->list)); 30423fd0a558SYan, Zheng btrfs_record_root_in_trans(trans, root); 30433fd0a558SYan, Zheng root = root->reloc_root; 30443fd0a558SYan, Zheng node->new_bytenr = root->node->start; 304500246528SJosef Bacik btrfs_put_root(node->root); 304600246528SJosef Bacik node->root = btrfs_grab_root(root); 30470b530bc5SJosef Bacik ASSERT(node->root); 30483fd0a558SYan, Zheng list_add_tail(&node->list, &rc->backref_cache.changed); 30493fd0a558SYan, Zheng } else { 30505d4f98a2SYan Zheng path->lowest_level = node->level; 30515d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 3052b3b4aa74SDavid Sterba btrfs_release_path(path); 30533fd0a558SYan, Zheng if (ret > 0) 30545d4f98a2SYan Zheng ret = 0; 30553fd0a558SYan, Zheng } 30563fd0a558SYan, Zheng if (!ret) 30573fd0a558SYan, Zheng update_processed_blocks(rc, node); 30583fd0a558SYan, Zheng } else { 30593fd0a558SYan, Zheng ret = do_relocation(trans, rc, node, key, path, 1); 30603fd0a558SYan, Zheng } 30615d4f98a2SYan Zheng out: 30620647bf56SWang Shilong if (ret || node->level == 0 || node->cowonly) 3063023acb07SQu Wenruo btrfs_backref_cleanup_node(&rc->backref_cache, node); 30645d4f98a2SYan Zheng return ret; 30655d4f98a2SYan Zheng } 30665d4f98a2SYan Zheng 30675d4f98a2SYan Zheng /* 30685d4f98a2SYan Zheng * relocate a list of blocks 30695d4f98a2SYan Zheng */ 30705d4f98a2SYan Zheng static noinline_for_stack 30715d4f98a2SYan Zheng int relocate_tree_blocks(struct btrfs_trans_handle *trans, 30725d4f98a2SYan Zheng struct reloc_control *rc, struct rb_root *blocks) 30735d4f98a2SYan Zheng { 30742ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 3075a26195a5SQu Wenruo struct btrfs_backref_node *node; 30765d4f98a2SYan Zheng struct btrfs_path *path; 30775d4f98a2SYan Zheng struct tree_block *block; 307898ff7b94SQu Wenruo struct tree_block *next; 30795d4f98a2SYan Zheng int ret; 30805d4f98a2SYan Zheng int err = 0; 30815d4f98a2SYan Zheng 30825d4f98a2SYan Zheng path = btrfs_alloc_path(); 3083e1a12670SLiu Bo if (!path) { 3084e1a12670SLiu Bo err = -ENOMEM; 308534c2b290SDavid Sterba goto out_free_blocks; 3086e1a12670SLiu Bo } 30875d4f98a2SYan Zheng 308898ff7b94SQu Wenruo /* Kick in readahead for tree blocks with missing keys */ 308998ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 30905d4f98a2SYan Zheng if (!block->key_ready) 30912ff7e61eSJeff Mahoney readahead_tree_block(fs_info, block->bytenr); 30925d4f98a2SYan Zheng } 30935d4f98a2SYan Zheng 309498ff7b94SQu Wenruo /* Get first keys */ 309598ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 309634c2b290SDavid Sterba if (!block->key_ready) { 30972ff7e61eSJeff Mahoney err = get_tree_block_key(fs_info, block); 309834c2b290SDavid Sterba if (err) 309934c2b290SDavid Sterba goto out_free_path; 310034c2b290SDavid Sterba } 31015d4f98a2SYan Zheng } 31025d4f98a2SYan Zheng 310398ff7b94SQu Wenruo /* Do tree relocation */ 310498ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 31053fd0a558SYan, Zheng node = build_backref_tree(rc, &block->key, 31065d4f98a2SYan Zheng block->level, block->bytenr); 31075d4f98a2SYan Zheng if (IS_ERR(node)) { 31085d4f98a2SYan Zheng err = PTR_ERR(node); 31095d4f98a2SYan Zheng goto out; 31105d4f98a2SYan Zheng } 31115d4f98a2SYan Zheng 31125d4f98a2SYan Zheng ret = relocate_tree_block(trans, rc, node, &block->key, 31135d4f98a2SYan Zheng path); 31145d4f98a2SYan Zheng if (ret < 0) { 31155d4f98a2SYan Zheng err = ret; 311650dbbb71SJosef Bacik break; 31175d4f98a2SYan Zheng } 31185d4f98a2SYan Zheng } 31195d4f98a2SYan Zheng out: 31203fd0a558SYan, Zheng err = finish_pending_nodes(trans, rc, path, err); 31215d4f98a2SYan Zheng 312234c2b290SDavid Sterba out_free_path: 31235d4f98a2SYan Zheng btrfs_free_path(path); 312434c2b290SDavid Sterba out_free_blocks: 3125e1a12670SLiu Bo free_block_list(blocks); 31265d4f98a2SYan Zheng return err; 31275d4f98a2SYan Zheng } 31285d4f98a2SYan Zheng 31295d4f98a2SYan Zheng static noinline_for_stack 3130efa56464SYan, Zheng int prealloc_file_extent_cluster(struct inode *inode, 3131efa56464SYan, Zheng struct file_extent_cluster *cluster) 3132efa56464SYan, Zheng { 3133efa56464SYan, Zheng u64 alloc_hint = 0; 3134efa56464SYan, Zheng u64 start; 3135efa56464SYan, Zheng u64 end; 3136efa56464SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 3137efa56464SYan, Zheng u64 num_bytes; 3138efa56464SYan, Zheng int nr = 0; 3139efa56464SYan, Zheng int ret = 0; 3140dcb40c19SWang Xiaoguang u64 prealloc_start = cluster->start - offset; 3141dcb40c19SWang Xiaoguang u64 prealloc_end = cluster->end - offset; 314218513091SWang Xiaoguang u64 cur_offset; 3143364ecf36SQu Wenruo struct extent_changeset *data_reserved = NULL; 3144efa56464SYan, Zheng 3145efa56464SYan, Zheng BUG_ON(cluster->start != cluster->boundary[0]); 31465955102cSAl Viro inode_lock(inode); 3147efa56464SYan, Zheng 3148364ecf36SQu Wenruo ret = btrfs_check_data_free_space(inode, &data_reserved, prealloc_start, 3149dcb40c19SWang Xiaoguang prealloc_end + 1 - prealloc_start); 3150efa56464SYan, Zheng if (ret) 3151efa56464SYan, Zheng goto out; 3152efa56464SYan, Zheng 315318513091SWang Xiaoguang cur_offset = prealloc_start; 3154efa56464SYan, Zheng while (nr < cluster->nr) { 3155efa56464SYan, Zheng start = cluster->boundary[nr] - offset; 3156efa56464SYan, Zheng if (nr + 1 < cluster->nr) 3157efa56464SYan, Zheng end = cluster->boundary[nr + 1] - 1 - offset; 3158efa56464SYan, Zheng else 3159efa56464SYan, Zheng end = cluster->end - offset; 3160efa56464SYan, Zheng 3161d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 3162efa56464SYan, Zheng num_bytes = end + 1 - start; 316318513091SWang Xiaoguang if (cur_offset < start) 3164bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3165bc42bda2SQu Wenruo cur_offset, start - cur_offset); 3166efa56464SYan, Zheng ret = btrfs_prealloc_file_range(inode, 0, start, 3167efa56464SYan, Zheng num_bytes, num_bytes, 3168efa56464SYan, Zheng end + 1, &alloc_hint); 316918513091SWang Xiaoguang cur_offset = end + 1; 3170d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 3171efa56464SYan, Zheng if (ret) 3172efa56464SYan, Zheng break; 3173efa56464SYan, Zheng nr++; 3174efa56464SYan, Zheng } 317518513091SWang Xiaoguang if (cur_offset < prealloc_end) 3176bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3177bc42bda2SQu Wenruo cur_offset, prealloc_end + 1 - cur_offset); 3178efa56464SYan, Zheng out: 31795955102cSAl Viro inode_unlock(inode); 3180364ecf36SQu Wenruo extent_changeset_free(data_reserved); 3181efa56464SYan, Zheng return ret; 3182efa56464SYan, Zheng } 3183efa56464SYan, Zheng 3184efa56464SYan, Zheng static noinline_for_stack 31850257bb82SYan, Zheng int setup_extent_mapping(struct inode *inode, u64 start, u64 end, 31860257bb82SYan, Zheng u64 block_start) 31875d4f98a2SYan Zheng { 31885d4f98a2SYan Zheng struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 31895d4f98a2SYan Zheng struct extent_map *em; 31900257bb82SYan, Zheng int ret = 0; 31915d4f98a2SYan Zheng 3192172ddd60SDavid Sterba em = alloc_extent_map(); 31930257bb82SYan, Zheng if (!em) 31940257bb82SYan, Zheng return -ENOMEM; 31950257bb82SYan, Zheng 31965d4f98a2SYan Zheng em->start = start; 31970257bb82SYan, Zheng em->len = end + 1 - start; 31980257bb82SYan, Zheng em->block_len = em->len; 31990257bb82SYan, Zheng em->block_start = block_start; 32005d4f98a2SYan Zheng set_bit(EXTENT_FLAG_PINNED, &em->flags); 32015d4f98a2SYan Zheng 3202d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 32035d4f98a2SYan Zheng while (1) { 3204890871beSChris Mason write_lock(&em_tree->lock); 320509a2a8f9SJosef Bacik ret = add_extent_mapping(em_tree, em, 0); 3206890871beSChris Mason write_unlock(&em_tree->lock); 32075d4f98a2SYan Zheng if (ret != -EEXIST) { 32085d4f98a2SYan Zheng free_extent_map(em); 32095d4f98a2SYan Zheng break; 32105d4f98a2SYan Zheng } 3211dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); 32125d4f98a2SYan Zheng } 3213d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 32140257bb82SYan, Zheng return ret; 32150257bb82SYan, Zheng } 32165d4f98a2SYan Zheng 3217726a3421SQu Wenruo /* 3218726a3421SQu Wenruo * Allow error injection to test balance cancellation 3219726a3421SQu Wenruo */ 3220726a3421SQu Wenruo int btrfs_should_cancel_balance(struct btrfs_fs_info *fs_info) 3221726a3421SQu Wenruo { 3222726a3421SQu Wenruo return atomic_read(&fs_info->balance_cancel_req); 3223726a3421SQu Wenruo } 3224726a3421SQu Wenruo ALLOW_ERROR_INJECTION(btrfs_should_cancel_balance, TRUE); 3225726a3421SQu Wenruo 32260257bb82SYan, Zheng static int relocate_file_extent_cluster(struct inode *inode, 32270257bb82SYan, Zheng struct file_extent_cluster *cluster) 32280257bb82SYan, Zheng { 32292ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 32300257bb82SYan, Zheng u64 page_start; 32310257bb82SYan, Zheng u64 page_end; 32320257bb82SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 32330257bb82SYan, Zheng unsigned long index; 32340257bb82SYan, Zheng unsigned long last_index; 32350257bb82SYan, Zheng struct page *page; 32360257bb82SYan, Zheng struct file_ra_state *ra; 32373b16a4e3SJosef Bacik gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 32380257bb82SYan, Zheng int nr = 0; 32390257bb82SYan, Zheng int ret = 0; 32400257bb82SYan, Zheng 32410257bb82SYan, Zheng if (!cluster->nr) 32420257bb82SYan, Zheng return 0; 32430257bb82SYan, Zheng 32440257bb82SYan, Zheng ra = kzalloc(sizeof(*ra), GFP_NOFS); 32450257bb82SYan, Zheng if (!ra) 32460257bb82SYan, Zheng return -ENOMEM; 32470257bb82SYan, Zheng 3248efa56464SYan, Zheng ret = prealloc_file_extent_cluster(inode, cluster); 32490257bb82SYan, Zheng if (ret) 3250efa56464SYan, Zheng goto out; 32510257bb82SYan, Zheng 32520257bb82SYan, Zheng file_ra_state_init(ra, inode->i_mapping); 32530257bb82SYan, Zheng 3254efa56464SYan, Zheng ret = setup_extent_mapping(inode, cluster->start - offset, 3255efa56464SYan, Zheng cluster->end - offset, cluster->start); 3256efa56464SYan, Zheng if (ret) 3257efa56464SYan, Zheng goto out; 3258efa56464SYan, Zheng 325909cbfeafSKirill A. Shutemov index = (cluster->start - offset) >> PAGE_SHIFT; 326009cbfeafSKirill A. Shutemov last_index = (cluster->end - offset) >> PAGE_SHIFT; 32610257bb82SYan, Zheng while (index <= last_index) { 32629f3db423SNikolay Borisov ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), 32639f3db423SNikolay Borisov PAGE_SIZE); 3264efa56464SYan, Zheng if (ret) 3265efa56464SYan, Zheng goto out; 3266efa56464SYan, Zheng 32670257bb82SYan, Zheng page = find_lock_page(inode->i_mapping, index); 32680257bb82SYan, Zheng if (!page) { 32690257bb82SYan, Zheng page_cache_sync_readahead(inode->i_mapping, 32700257bb82SYan, Zheng ra, NULL, index, 32710257bb82SYan, Zheng last_index + 1 - index); 3272a94733d0SJosef Bacik page = find_or_create_page(inode->i_mapping, index, 32733b16a4e3SJosef Bacik mask); 32740257bb82SYan, Zheng if (!page) { 3275691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 327643b18595SQu Wenruo PAGE_SIZE, true); 327744db1216SFilipe Manana btrfs_delalloc_release_extents(BTRFS_I(inode), 32788702ba93SQu Wenruo PAGE_SIZE); 32790257bb82SYan, Zheng ret = -ENOMEM; 3280efa56464SYan, Zheng goto out; 32810257bb82SYan, Zheng } 32820257bb82SYan, Zheng } 32830257bb82SYan, Zheng 32840257bb82SYan, Zheng if (PageReadahead(page)) { 32850257bb82SYan, Zheng page_cache_async_readahead(inode->i_mapping, 32860257bb82SYan, Zheng ra, NULL, page, index, 32870257bb82SYan, Zheng last_index + 1 - index); 32880257bb82SYan, Zheng } 32890257bb82SYan, Zheng 32900257bb82SYan, Zheng if (!PageUptodate(page)) { 32910257bb82SYan, Zheng btrfs_readpage(NULL, page); 32920257bb82SYan, Zheng lock_page(page); 32930257bb82SYan, Zheng if (!PageUptodate(page)) { 32940257bb82SYan, Zheng unlock_page(page); 329509cbfeafSKirill A. Shutemov put_page(page); 3296691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 329743b18595SQu Wenruo PAGE_SIZE, true); 32988b62f87bSJosef Bacik btrfs_delalloc_release_extents(BTRFS_I(inode), 32998702ba93SQu Wenruo PAGE_SIZE); 33000257bb82SYan, Zheng ret = -EIO; 3301efa56464SYan, Zheng goto out; 33020257bb82SYan, Zheng } 33030257bb82SYan, Zheng } 33040257bb82SYan, Zheng 33054eee4fa4SMiao Xie page_start = page_offset(page); 330609cbfeafSKirill A. Shutemov page_end = page_start + PAGE_SIZE - 1; 33070257bb82SYan, Zheng 3308d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end); 33090257bb82SYan, Zheng 33100257bb82SYan, Zheng set_page_extent_mapped(page); 33110257bb82SYan, Zheng 33120257bb82SYan, Zheng if (nr < cluster->nr && 33130257bb82SYan, Zheng page_start + offset == cluster->boundary[nr]) { 33140257bb82SYan, Zheng set_extent_bits(&BTRFS_I(inode)->io_tree, 33150257bb82SYan, Zheng page_start, page_end, 3316ceeb0ae7SDavid Sterba EXTENT_BOUNDARY); 33170257bb82SYan, Zheng nr++; 33180257bb82SYan, Zheng } 33190257bb82SYan, Zheng 3320765f3cebSNikolay Borisov ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, 3321330a5827SNikolay Borisov NULL); 3322765f3cebSNikolay Borisov if (ret) { 3323765f3cebSNikolay Borisov unlock_page(page); 3324765f3cebSNikolay Borisov put_page(page); 3325765f3cebSNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 332643b18595SQu Wenruo PAGE_SIZE, true); 3327765f3cebSNikolay Borisov btrfs_delalloc_release_extents(BTRFS_I(inode), 33288702ba93SQu Wenruo PAGE_SIZE); 3329765f3cebSNikolay Borisov 3330765f3cebSNikolay Borisov clear_extent_bits(&BTRFS_I(inode)->io_tree, 3331765f3cebSNikolay Borisov page_start, page_end, 3332765f3cebSNikolay Borisov EXTENT_LOCKED | EXTENT_BOUNDARY); 3333765f3cebSNikolay Borisov goto out; 3334765f3cebSNikolay Borisov 3335765f3cebSNikolay Borisov } 33360257bb82SYan, Zheng set_page_dirty(page); 33370257bb82SYan, Zheng 33380257bb82SYan, Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 3339d0082371SJeff Mahoney page_start, page_end); 33400257bb82SYan, Zheng unlock_page(page); 334109cbfeafSKirill A. Shutemov put_page(page); 33420257bb82SYan, Zheng 33430257bb82SYan, Zheng index++; 33448702ba93SQu Wenruo btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); 3345efa56464SYan, Zheng balance_dirty_pages_ratelimited(inode->i_mapping); 33462ff7e61eSJeff Mahoney btrfs_throttle(fs_info); 33477f913c7cSQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 33487f913c7cSQu Wenruo ret = -ECANCELED; 33497f913c7cSQu Wenruo goto out; 33507f913c7cSQu Wenruo } 33510257bb82SYan, Zheng } 33520257bb82SYan, Zheng WARN_ON(nr != cluster->nr); 3353efa56464SYan, Zheng out: 33540257bb82SYan, Zheng kfree(ra); 33550257bb82SYan, Zheng return ret; 33560257bb82SYan, Zheng } 33570257bb82SYan, Zheng 33580257bb82SYan, Zheng static noinline_for_stack 33590257bb82SYan, Zheng int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, 33600257bb82SYan, Zheng struct file_extent_cluster *cluster) 33610257bb82SYan, Zheng { 33620257bb82SYan, Zheng int ret; 33630257bb82SYan, Zheng 33640257bb82SYan, Zheng if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) { 33650257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 33660257bb82SYan, Zheng if (ret) 33670257bb82SYan, Zheng return ret; 33680257bb82SYan, Zheng cluster->nr = 0; 33690257bb82SYan, Zheng } 33700257bb82SYan, Zheng 33710257bb82SYan, Zheng if (!cluster->nr) 33720257bb82SYan, Zheng cluster->start = extent_key->objectid; 33730257bb82SYan, Zheng else 33740257bb82SYan, Zheng BUG_ON(cluster->nr >= MAX_EXTENTS); 33750257bb82SYan, Zheng cluster->end = extent_key->objectid + extent_key->offset - 1; 33760257bb82SYan, Zheng cluster->boundary[cluster->nr] = extent_key->objectid; 33770257bb82SYan, Zheng cluster->nr++; 33780257bb82SYan, Zheng 33790257bb82SYan, Zheng if (cluster->nr >= MAX_EXTENTS) { 33800257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 33810257bb82SYan, Zheng if (ret) 33820257bb82SYan, Zheng return ret; 33830257bb82SYan, Zheng cluster->nr = 0; 33840257bb82SYan, Zheng } 33850257bb82SYan, Zheng return 0; 33865d4f98a2SYan Zheng } 33875d4f98a2SYan Zheng 33885d4f98a2SYan Zheng /* 33895d4f98a2SYan Zheng * helper to add a tree block to the list. 33905d4f98a2SYan Zheng * the major work is getting the generation and level of the block 33915d4f98a2SYan Zheng */ 33925d4f98a2SYan Zheng static int add_tree_block(struct reloc_control *rc, 33935d4f98a2SYan Zheng struct btrfs_key *extent_key, 33945d4f98a2SYan Zheng struct btrfs_path *path, 33955d4f98a2SYan Zheng struct rb_root *blocks) 33965d4f98a2SYan Zheng { 33975d4f98a2SYan Zheng struct extent_buffer *eb; 33985d4f98a2SYan Zheng struct btrfs_extent_item *ei; 33995d4f98a2SYan Zheng struct btrfs_tree_block_info *bi; 34005d4f98a2SYan Zheng struct tree_block *block; 34015d4f98a2SYan Zheng struct rb_node *rb_node; 34025d4f98a2SYan Zheng u32 item_size; 34035d4f98a2SYan Zheng int level = -1; 34047fdf4b60SWang Shilong u64 generation; 34055d4f98a2SYan Zheng 34065d4f98a2SYan Zheng eb = path->nodes[0]; 34075d4f98a2SYan Zheng item_size = btrfs_item_size_nr(eb, path->slots[0]); 34085d4f98a2SYan Zheng 34093173a18fSJosef Bacik if (extent_key->type == BTRFS_METADATA_ITEM_KEY || 34103173a18fSJosef Bacik item_size >= sizeof(*ei) + sizeof(*bi)) { 34115d4f98a2SYan Zheng ei = btrfs_item_ptr(eb, path->slots[0], 34125d4f98a2SYan Zheng struct btrfs_extent_item); 34133173a18fSJosef Bacik if (extent_key->type == BTRFS_EXTENT_ITEM_KEY) { 34145d4f98a2SYan Zheng bi = (struct btrfs_tree_block_info *)(ei + 1); 34155d4f98a2SYan Zheng level = btrfs_tree_block_level(eb, bi); 34165d4f98a2SYan Zheng } else { 34173173a18fSJosef Bacik level = (int)extent_key->offset; 34183173a18fSJosef Bacik } 34193173a18fSJosef Bacik generation = btrfs_extent_generation(eb, ei); 34206d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3421ba3c2b19SNikolay Borisov btrfs_print_v0_err(eb->fs_info); 3422ba3c2b19SNikolay Borisov btrfs_handle_fs_error(eb->fs_info, -EINVAL, NULL); 3423ba3c2b19SNikolay Borisov return -EINVAL; 34243173a18fSJosef Bacik } else { 34255d4f98a2SYan Zheng BUG(); 34265d4f98a2SYan Zheng } 34275d4f98a2SYan Zheng 3428b3b4aa74SDavid Sterba btrfs_release_path(path); 34295d4f98a2SYan Zheng 34305d4f98a2SYan Zheng BUG_ON(level == -1); 34315d4f98a2SYan Zheng 34325d4f98a2SYan Zheng block = kmalloc(sizeof(*block), GFP_NOFS); 34335d4f98a2SYan Zheng if (!block) 34345d4f98a2SYan Zheng return -ENOMEM; 34355d4f98a2SYan Zheng 34365d4f98a2SYan Zheng block->bytenr = extent_key->objectid; 3437da17066cSJeff Mahoney block->key.objectid = rc->extent_root->fs_info->nodesize; 34385d4f98a2SYan Zheng block->key.offset = generation; 34395d4f98a2SYan Zheng block->level = level; 34405d4f98a2SYan Zheng block->key_ready = 0; 34415d4f98a2SYan Zheng 3442e9a28dc5SQu Wenruo rb_node = rb_simple_insert(blocks, block->bytenr, &block->rb_node); 344343c04fb1SJeff Mahoney if (rb_node) 344443c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, block->bytenr); 34455d4f98a2SYan Zheng 34465d4f98a2SYan Zheng return 0; 34475d4f98a2SYan Zheng } 34485d4f98a2SYan Zheng 34495d4f98a2SYan Zheng /* 34505d4f98a2SYan Zheng * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY 34515d4f98a2SYan Zheng */ 34525d4f98a2SYan Zheng static int __add_tree_block(struct reloc_control *rc, 34535d4f98a2SYan Zheng u64 bytenr, u32 blocksize, 34545d4f98a2SYan Zheng struct rb_root *blocks) 34555d4f98a2SYan Zheng { 34560b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 34575d4f98a2SYan Zheng struct btrfs_path *path; 34585d4f98a2SYan Zheng struct btrfs_key key; 34595d4f98a2SYan Zheng int ret; 34600b246afaSJeff Mahoney bool skinny = btrfs_fs_incompat(fs_info, SKINNY_METADATA); 34615d4f98a2SYan Zheng 34627476dfdaSDavid Sterba if (tree_block_processed(bytenr, rc)) 34635d4f98a2SYan Zheng return 0; 34645d4f98a2SYan Zheng 3465e9a28dc5SQu Wenruo if (rb_simple_search(blocks, bytenr)) 34665d4f98a2SYan Zheng return 0; 34675d4f98a2SYan Zheng 34685d4f98a2SYan Zheng path = btrfs_alloc_path(); 34695d4f98a2SYan Zheng if (!path) 34705d4f98a2SYan Zheng return -ENOMEM; 3471aee68ee5SJosef Bacik again: 34725d4f98a2SYan Zheng key.objectid = bytenr; 3473aee68ee5SJosef Bacik if (skinny) { 3474aee68ee5SJosef Bacik key.type = BTRFS_METADATA_ITEM_KEY; 3475aee68ee5SJosef Bacik key.offset = (u64)-1; 3476aee68ee5SJosef Bacik } else { 34775d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 34785d4f98a2SYan Zheng key.offset = blocksize; 3479aee68ee5SJosef Bacik } 34805d4f98a2SYan Zheng 34815d4f98a2SYan Zheng path->search_commit_root = 1; 34825d4f98a2SYan Zheng path->skip_locking = 1; 34835d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); 34845d4f98a2SYan Zheng if (ret < 0) 34855d4f98a2SYan Zheng goto out; 34865d4f98a2SYan Zheng 3487aee68ee5SJosef Bacik if (ret > 0 && skinny) { 3488aee68ee5SJosef Bacik if (path->slots[0]) { 3489aee68ee5SJosef Bacik path->slots[0]--; 3490aee68ee5SJosef Bacik btrfs_item_key_to_cpu(path->nodes[0], &key, 3491aee68ee5SJosef Bacik path->slots[0]); 34923173a18fSJosef Bacik if (key.objectid == bytenr && 3493aee68ee5SJosef Bacik (key.type == BTRFS_METADATA_ITEM_KEY || 3494aee68ee5SJosef Bacik (key.type == BTRFS_EXTENT_ITEM_KEY && 3495aee68ee5SJosef Bacik key.offset == blocksize))) 34963173a18fSJosef Bacik ret = 0; 34973173a18fSJosef Bacik } 3498aee68ee5SJosef Bacik 3499aee68ee5SJosef Bacik if (ret) { 3500aee68ee5SJosef Bacik skinny = false; 3501aee68ee5SJosef Bacik btrfs_release_path(path); 3502aee68ee5SJosef Bacik goto again; 3503aee68ee5SJosef Bacik } 3504aee68ee5SJosef Bacik } 3505cdccee99SLiu Bo if (ret) { 3506cdccee99SLiu Bo ASSERT(ret == 1); 3507cdccee99SLiu Bo btrfs_print_leaf(path->nodes[0]); 3508cdccee99SLiu Bo btrfs_err(fs_info, 3509cdccee99SLiu Bo "tree block extent item (%llu) is not found in extent tree", 3510cdccee99SLiu Bo bytenr); 3511cdccee99SLiu Bo WARN_ON(1); 3512cdccee99SLiu Bo ret = -EINVAL; 3513cdccee99SLiu Bo goto out; 3514cdccee99SLiu Bo } 35153173a18fSJosef Bacik 35165d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, blocks); 35175d4f98a2SYan Zheng out: 35185d4f98a2SYan Zheng btrfs_free_path(path); 35195d4f98a2SYan Zheng return ret; 35205d4f98a2SYan Zheng } 35215d4f98a2SYan Zheng 35220af3d00bSJosef Bacik static int delete_block_group_cache(struct btrfs_fs_info *fs_info, 352332da5386SDavid Sterba struct btrfs_block_group *block_group, 35241bbc621eSChris Mason struct inode *inode, 35251bbc621eSChris Mason u64 ino) 35260af3d00bSJosef Bacik { 35270af3d00bSJosef Bacik struct btrfs_key key; 35280af3d00bSJosef Bacik struct btrfs_root *root = fs_info->tree_root; 35290af3d00bSJosef Bacik struct btrfs_trans_handle *trans; 35300af3d00bSJosef Bacik int ret = 0; 35310af3d00bSJosef Bacik 35320af3d00bSJosef Bacik if (inode) 35330af3d00bSJosef Bacik goto truncate; 35340af3d00bSJosef Bacik 35350af3d00bSJosef Bacik key.objectid = ino; 35360af3d00bSJosef Bacik key.type = BTRFS_INODE_ITEM_KEY; 35370af3d00bSJosef Bacik key.offset = 0; 35380af3d00bSJosef Bacik 35394c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 35402e19f1f9SAl Viro if (IS_ERR(inode)) 35410af3d00bSJosef Bacik return -ENOENT; 35420af3d00bSJosef Bacik 35430af3d00bSJosef Bacik truncate: 35442ff7e61eSJeff Mahoney ret = btrfs_check_trunc_cache_free_space(fs_info, 35457b61cd92SMiao Xie &fs_info->global_block_rsv); 35467b61cd92SMiao Xie if (ret) 35477b61cd92SMiao Xie goto out; 35487b61cd92SMiao Xie 35497a7eaa40SJosef Bacik trans = btrfs_join_transaction(root); 35500af3d00bSJosef Bacik if (IS_ERR(trans)) { 35513612b495STsutomu Itoh ret = PTR_ERR(trans); 35520af3d00bSJosef Bacik goto out; 35530af3d00bSJosef Bacik } 35540af3d00bSJosef Bacik 355577ab86bfSJeff Mahoney ret = btrfs_truncate_free_space_cache(trans, block_group, inode); 35560af3d00bSJosef Bacik 35573a45bb20SJeff Mahoney btrfs_end_transaction(trans); 35582ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 35590af3d00bSJosef Bacik out: 35600af3d00bSJosef Bacik iput(inode); 35610af3d00bSJosef Bacik return ret; 35620af3d00bSJosef Bacik } 35630af3d00bSJosef Bacik 35645d4f98a2SYan Zheng /* 356519b546d7SQu Wenruo * Locate the free space cache EXTENT_DATA in root tree leaf and delete the 356619b546d7SQu Wenruo * cache inode, to avoid free space cache data extent blocking data relocation. 35675d4f98a2SYan Zheng */ 356819b546d7SQu Wenruo static int delete_v1_space_cache(struct extent_buffer *leaf, 356919b546d7SQu Wenruo struct btrfs_block_group *block_group, 357019b546d7SQu Wenruo u64 data_bytenr) 35715d4f98a2SYan Zheng { 357219b546d7SQu Wenruo u64 space_cache_ino; 357319b546d7SQu Wenruo struct btrfs_file_extent_item *ei; 35745d4f98a2SYan Zheng struct btrfs_key key; 357519b546d7SQu Wenruo bool found = false; 357619b546d7SQu Wenruo int i; 35775d4f98a2SYan Zheng int ret; 35785d4f98a2SYan Zheng 357919b546d7SQu Wenruo if (btrfs_header_owner(leaf) != BTRFS_ROOT_TREE_OBJECTID) 358019b546d7SQu Wenruo return 0; 35815d4f98a2SYan Zheng 358219b546d7SQu Wenruo for (i = 0; i < btrfs_header_nritems(leaf); i++) { 358319b546d7SQu Wenruo btrfs_item_key_to_cpu(leaf, &key, i); 358419b546d7SQu Wenruo if (key.type != BTRFS_EXTENT_DATA_KEY) 358519b546d7SQu Wenruo continue; 358619b546d7SQu Wenruo ei = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 358719b546d7SQu Wenruo if (btrfs_file_extent_type(leaf, ei) == BTRFS_FILE_EXTENT_REG && 358819b546d7SQu Wenruo btrfs_file_extent_disk_bytenr(leaf, ei) == data_bytenr) { 358919b546d7SQu Wenruo found = true; 359019b546d7SQu Wenruo space_cache_ino = key.objectid; 359119b546d7SQu Wenruo break; 359219b546d7SQu Wenruo } 359319b546d7SQu Wenruo } 359419b546d7SQu Wenruo if (!found) 359519b546d7SQu Wenruo return -ENOENT; 359619b546d7SQu Wenruo ret = delete_block_group_cache(leaf->fs_info, block_group, NULL, 359719b546d7SQu Wenruo space_cache_ino); 35980af3d00bSJosef Bacik return ret; 35995d4f98a2SYan Zheng } 36005d4f98a2SYan Zheng 36015d4f98a2SYan Zheng /* 36022c016dc2SLiu Bo * helper to find all tree blocks that reference a given data extent 36035d4f98a2SYan Zheng */ 36045d4f98a2SYan Zheng static noinline_for_stack 36055d4f98a2SYan Zheng int add_data_references(struct reloc_control *rc, 36065d4f98a2SYan Zheng struct btrfs_key *extent_key, 36075d4f98a2SYan Zheng struct btrfs_path *path, 36085d4f98a2SYan Zheng struct rb_root *blocks) 36095d4f98a2SYan Zheng { 361019b546d7SQu Wenruo struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 361119b546d7SQu Wenruo struct ulist *leaves = NULL; 361219b546d7SQu Wenruo struct ulist_iterator leaf_uiter; 361319b546d7SQu Wenruo struct ulist_node *ref_node = NULL; 361419b546d7SQu Wenruo const u32 blocksize = fs_info->nodesize; 3615647f63bdSFilipe David Borba Manana int ret = 0; 36165d4f98a2SYan Zheng 3617b3b4aa74SDavid Sterba btrfs_release_path(path); 361819b546d7SQu Wenruo ret = btrfs_find_all_leafs(NULL, fs_info, extent_key->objectid, 361919b546d7SQu Wenruo 0, &leaves, NULL, true); 362019b546d7SQu Wenruo if (ret < 0) 362119b546d7SQu Wenruo return ret; 362219b546d7SQu Wenruo 362319b546d7SQu Wenruo ULIST_ITER_INIT(&leaf_uiter); 362419b546d7SQu Wenruo while ((ref_node = ulist_next(leaves, &leaf_uiter))) { 362519b546d7SQu Wenruo struct extent_buffer *eb; 362619b546d7SQu Wenruo 362719b546d7SQu Wenruo eb = read_tree_block(fs_info, ref_node->val, 0, 0, NULL); 362819b546d7SQu Wenruo if (IS_ERR(eb)) { 362919b546d7SQu Wenruo ret = PTR_ERR(eb); 363019b546d7SQu Wenruo break; 363119b546d7SQu Wenruo } 363219b546d7SQu Wenruo ret = delete_v1_space_cache(eb, rc->block_group, 363319b546d7SQu Wenruo extent_key->objectid); 363419b546d7SQu Wenruo free_extent_buffer(eb); 363519b546d7SQu Wenruo if (ret < 0) 363619b546d7SQu Wenruo break; 363719b546d7SQu Wenruo ret = __add_tree_block(rc, ref_node->val, blocksize, blocks); 363819b546d7SQu Wenruo if (ret < 0) 363919b546d7SQu Wenruo break; 364019b546d7SQu Wenruo } 364119b546d7SQu Wenruo if (ret < 0) 36425d4f98a2SYan Zheng free_block_list(blocks); 364319b546d7SQu Wenruo ulist_free(leaves); 364419b546d7SQu Wenruo return ret; 36455d4f98a2SYan Zheng } 36465d4f98a2SYan Zheng 36475d4f98a2SYan Zheng /* 36482c016dc2SLiu Bo * helper to find next unprocessed extent 36495d4f98a2SYan Zheng */ 36505d4f98a2SYan Zheng static noinline_for_stack 3651147d256eSZhaolei int find_next_extent(struct reloc_control *rc, struct btrfs_path *path, 36523fd0a558SYan, Zheng struct btrfs_key *extent_key) 36535d4f98a2SYan Zheng { 36540b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 36555d4f98a2SYan Zheng struct btrfs_key key; 36565d4f98a2SYan Zheng struct extent_buffer *leaf; 36575d4f98a2SYan Zheng u64 start, end, last; 36585d4f98a2SYan Zheng int ret; 36595d4f98a2SYan Zheng 3660b3470b5dSDavid Sterba last = rc->block_group->start + rc->block_group->length; 36615d4f98a2SYan Zheng while (1) { 36625d4f98a2SYan Zheng cond_resched(); 36635d4f98a2SYan Zheng if (rc->search_start >= last) { 36645d4f98a2SYan Zheng ret = 1; 36655d4f98a2SYan Zheng break; 36665d4f98a2SYan Zheng } 36675d4f98a2SYan Zheng 36685d4f98a2SYan Zheng key.objectid = rc->search_start; 36695d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 36705d4f98a2SYan Zheng key.offset = 0; 36715d4f98a2SYan Zheng 36725d4f98a2SYan Zheng path->search_commit_root = 1; 36735d4f98a2SYan Zheng path->skip_locking = 1; 36745d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 36755d4f98a2SYan Zheng 0, 0); 36765d4f98a2SYan Zheng if (ret < 0) 36775d4f98a2SYan Zheng break; 36785d4f98a2SYan Zheng next: 36795d4f98a2SYan Zheng leaf = path->nodes[0]; 36805d4f98a2SYan Zheng if (path->slots[0] >= btrfs_header_nritems(leaf)) { 36815d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 36825d4f98a2SYan Zheng if (ret != 0) 36835d4f98a2SYan Zheng break; 36845d4f98a2SYan Zheng leaf = path->nodes[0]; 36855d4f98a2SYan Zheng } 36865d4f98a2SYan Zheng 36875d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 36885d4f98a2SYan Zheng if (key.objectid >= last) { 36895d4f98a2SYan Zheng ret = 1; 36905d4f98a2SYan Zheng break; 36915d4f98a2SYan Zheng } 36925d4f98a2SYan Zheng 36933173a18fSJosef Bacik if (key.type != BTRFS_EXTENT_ITEM_KEY && 36943173a18fSJosef Bacik key.type != BTRFS_METADATA_ITEM_KEY) { 36953173a18fSJosef Bacik path->slots[0]++; 36963173a18fSJosef Bacik goto next; 36973173a18fSJosef Bacik } 36983173a18fSJosef Bacik 36993173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY && 37005d4f98a2SYan Zheng key.objectid + key.offset <= rc->search_start) { 37015d4f98a2SYan Zheng path->slots[0]++; 37025d4f98a2SYan Zheng goto next; 37035d4f98a2SYan Zheng } 37045d4f98a2SYan Zheng 37053173a18fSJosef Bacik if (key.type == BTRFS_METADATA_ITEM_KEY && 37060b246afaSJeff Mahoney key.objectid + fs_info->nodesize <= 37073173a18fSJosef Bacik rc->search_start) { 37083173a18fSJosef Bacik path->slots[0]++; 37093173a18fSJosef Bacik goto next; 37103173a18fSJosef Bacik } 37113173a18fSJosef Bacik 37125d4f98a2SYan Zheng ret = find_first_extent_bit(&rc->processed_blocks, 37135d4f98a2SYan Zheng key.objectid, &start, &end, 3714e6138876SJosef Bacik EXTENT_DIRTY, NULL); 37155d4f98a2SYan Zheng 37165d4f98a2SYan Zheng if (ret == 0 && start <= key.objectid) { 3717b3b4aa74SDavid Sterba btrfs_release_path(path); 37185d4f98a2SYan Zheng rc->search_start = end + 1; 37195d4f98a2SYan Zheng } else { 37203173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY) 37215d4f98a2SYan Zheng rc->search_start = key.objectid + key.offset; 37223173a18fSJosef Bacik else 37233173a18fSJosef Bacik rc->search_start = key.objectid + 37240b246afaSJeff Mahoney fs_info->nodesize; 37253fd0a558SYan, Zheng memcpy(extent_key, &key, sizeof(key)); 37265d4f98a2SYan Zheng return 0; 37275d4f98a2SYan Zheng } 37285d4f98a2SYan Zheng } 3729b3b4aa74SDavid Sterba btrfs_release_path(path); 37305d4f98a2SYan Zheng return ret; 37315d4f98a2SYan Zheng } 37325d4f98a2SYan Zheng 37335d4f98a2SYan Zheng static void set_reloc_control(struct reloc_control *rc) 37345d4f98a2SYan Zheng { 37355d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37367585717fSChris Mason 37377585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 37385d4f98a2SYan Zheng fs_info->reloc_ctl = rc; 37397585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 37405d4f98a2SYan Zheng } 37415d4f98a2SYan Zheng 37425d4f98a2SYan Zheng static void unset_reloc_control(struct reloc_control *rc) 37435d4f98a2SYan Zheng { 37445d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37457585717fSChris Mason 37467585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 37475d4f98a2SYan Zheng fs_info->reloc_ctl = NULL; 37487585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 37495d4f98a2SYan Zheng } 37505d4f98a2SYan Zheng 37515d4f98a2SYan Zheng static int check_extent_flags(u64 flags) 37525d4f98a2SYan Zheng { 37535d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 37545d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 37555d4f98a2SYan Zheng return 1; 37565d4f98a2SYan Zheng if (!(flags & BTRFS_EXTENT_FLAG_DATA) && 37575d4f98a2SYan Zheng !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 37585d4f98a2SYan Zheng return 1; 37595d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 37605d4f98a2SYan Zheng (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) 37615d4f98a2SYan Zheng return 1; 37625d4f98a2SYan Zheng return 0; 37635d4f98a2SYan Zheng } 37645d4f98a2SYan Zheng 37653fd0a558SYan, Zheng static noinline_for_stack 37663fd0a558SYan, Zheng int prepare_to_relocate(struct reloc_control *rc) 37673fd0a558SYan, Zheng { 37683fd0a558SYan, Zheng struct btrfs_trans_handle *trans; 3769ac2fabacSJosef Bacik int ret; 37703fd0a558SYan, Zheng 37712ff7e61eSJeff Mahoney rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root->fs_info, 377266d8f3ddSMiao Xie BTRFS_BLOCK_RSV_TEMP); 37733fd0a558SYan, Zheng if (!rc->block_rsv) 37743fd0a558SYan, Zheng return -ENOMEM; 37753fd0a558SYan, Zheng 37763fd0a558SYan, Zheng memset(&rc->cluster, 0, sizeof(rc->cluster)); 3777b3470b5dSDavid Sterba rc->search_start = rc->block_group->start; 37783fd0a558SYan, Zheng rc->extents_found = 0; 37793fd0a558SYan, Zheng rc->nodes_relocated = 0; 37803fd0a558SYan, Zheng rc->merging_rsv_size = 0; 37810647bf56SWang Shilong rc->reserved_bytes = 0; 3782da17066cSJeff Mahoney rc->block_rsv->size = rc->extent_root->fs_info->nodesize * 37830647bf56SWang Shilong RELOCATION_RESERVED_NODES; 3784ac2fabacSJosef Bacik ret = btrfs_block_rsv_refill(rc->extent_root, 3785ac2fabacSJosef Bacik rc->block_rsv, rc->block_rsv->size, 3786ac2fabacSJosef Bacik BTRFS_RESERVE_FLUSH_ALL); 3787ac2fabacSJosef Bacik if (ret) 3788ac2fabacSJosef Bacik return ret; 37893fd0a558SYan, Zheng 37903fd0a558SYan, Zheng rc->create_reloc_tree = 1; 37913fd0a558SYan, Zheng set_reloc_control(rc); 37923fd0a558SYan, Zheng 37937a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 379428818947SLiu Bo if (IS_ERR(trans)) { 379528818947SLiu Bo unset_reloc_control(rc); 379628818947SLiu Bo /* 379728818947SLiu Bo * extent tree is not a ref_cow tree and has no reloc_root to 379828818947SLiu Bo * cleanup. And callers are responsible to free the above 379928818947SLiu Bo * block rsv. 380028818947SLiu Bo */ 380128818947SLiu Bo return PTR_ERR(trans); 380228818947SLiu Bo } 38033a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 38043fd0a558SYan, Zheng return 0; 38053fd0a558SYan, Zheng } 380676dda93cSYan, Zheng 38075d4f98a2SYan Zheng static noinline_for_stack int relocate_block_group(struct reloc_control *rc) 38085d4f98a2SYan Zheng { 38092ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 38105d4f98a2SYan Zheng struct rb_root blocks = RB_ROOT; 38115d4f98a2SYan Zheng struct btrfs_key key; 38125d4f98a2SYan Zheng struct btrfs_trans_handle *trans = NULL; 38135d4f98a2SYan Zheng struct btrfs_path *path; 38145d4f98a2SYan Zheng struct btrfs_extent_item *ei; 38155d4f98a2SYan Zheng u64 flags; 38165d4f98a2SYan Zheng u32 item_size; 38175d4f98a2SYan Zheng int ret; 38185d4f98a2SYan Zheng int err = 0; 3819c87f08caSChris Mason int progress = 0; 38205d4f98a2SYan Zheng 38215d4f98a2SYan Zheng path = btrfs_alloc_path(); 38223fd0a558SYan, Zheng if (!path) 38235d4f98a2SYan Zheng return -ENOMEM; 3824e4058b54SDavid Sterba path->reada = READA_FORWARD; 38253fd0a558SYan, Zheng 38263fd0a558SYan, Zheng ret = prepare_to_relocate(rc); 38273fd0a558SYan, Zheng if (ret) { 38283fd0a558SYan, Zheng err = ret; 38293fd0a558SYan, Zheng goto out_free; 38302423fdfbSJiri Slaby } 38315d4f98a2SYan Zheng 38325d4f98a2SYan Zheng while (1) { 38330647bf56SWang Shilong rc->reserved_bytes = 0; 38340647bf56SWang Shilong ret = btrfs_block_rsv_refill(rc->extent_root, 38350647bf56SWang Shilong rc->block_rsv, rc->block_rsv->size, 38360647bf56SWang Shilong BTRFS_RESERVE_FLUSH_ALL); 38370647bf56SWang Shilong if (ret) { 38380647bf56SWang Shilong err = ret; 38390647bf56SWang Shilong break; 38400647bf56SWang Shilong } 3841c87f08caSChris Mason progress++; 3842a22285a6SYan, Zheng trans = btrfs_start_transaction(rc->extent_root, 0); 38430f788c58SLiu Bo if (IS_ERR(trans)) { 38440f788c58SLiu Bo err = PTR_ERR(trans); 38450f788c58SLiu Bo trans = NULL; 38460f788c58SLiu Bo break; 38470f788c58SLiu Bo } 3848c87f08caSChris Mason restart: 38493fd0a558SYan, Zheng if (update_backref_cache(trans, &rc->backref_cache)) { 38503a45bb20SJeff Mahoney btrfs_end_transaction(trans); 385142a657f5SPan Bian trans = NULL; 38523fd0a558SYan, Zheng continue; 38533fd0a558SYan, Zheng } 38543fd0a558SYan, Zheng 3855147d256eSZhaolei ret = find_next_extent(rc, path, &key); 38565d4f98a2SYan Zheng if (ret < 0) 38575d4f98a2SYan Zheng err = ret; 38585d4f98a2SYan Zheng if (ret != 0) 38595d4f98a2SYan Zheng break; 38605d4f98a2SYan Zheng 38615d4f98a2SYan Zheng rc->extents_found++; 38625d4f98a2SYan Zheng 38635d4f98a2SYan Zheng ei = btrfs_item_ptr(path->nodes[0], path->slots[0], 38645d4f98a2SYan Zheng struct btrfs_extent_item); 38653fd0a558SYan, Zheng item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); 38665d4f98a2SYan Zheng if (item_size >= sizeof(*ei)) { 38675d4f98a2SYan Zheng flags = btrfs_extent_flags(path->nodes[0], ei); 38685d4f98a2SYan Zheng ret = check_extent_flags(flags); 38695d4f98a2SYan Zheng BUG_ON(ret); 38706d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3871ba3c2b19SNikolay Borisov err = -EINVAL; 3872ba3c2b19SNikolay Borisov btrfs_print_v0_err(trans->fs_info); 3873ba3c2b19SNikolay Borisov btrfs_abort_transaction(trans, err); 3874ba3c2b19SNikolay Borisov break; 38755d4f98a2SYan Zheng } else { 38765d4f98a2SYan Zheng BUG(); 38775d4f98a2SYan Zheng } 38785d4f98a2SYan Zheng 38795d4f98a2SYan Zheng if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 38805d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, &blocks); 38815d4f98a2SYan Zheng } else if (rc->stage == UPDATE_DATA_PTRS && 38825d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 38835d4f98a2SYan Zheng ret = add_data_references(rc, &key, path, &blocks); 38845d4f98a2SYan Zheng } else { 3885b3b4aa74SDavid Sterba btrfs_release_path(path); 38865d4f98a2SYan Zheng ret = 0; 38875d4f98a2SYan Zheng } 38885d4f98a2SYan Zheng if (ret < 0) { 38893fd0a558SYan, Zheng err = ret; 38905d4f98a2SYan Zheng break; 38915d4f98a2SYan Zheng } 38925d4f98a2SYan Zheng 38935d4f98a2SYan Zheng if (!RB_EMPTY_ROOT(&blocks)) { 38945d4f98a2SYan Zheng ret = relocate_tree_blocks(trans, rc, &blocks); 38955d4f98a2SYan Zheng if (ret < 0) { 38963fd0a558SYan, Zheng if (ret != -EAGAIN) { 38975d4f98a2SYan Zheng err = ret; 38985d4f98a2SYan Zheng break; 38995d4f98a2SYan Zheng } 39003fd0a558SYan, Zheng rc->extents_found--; 39013fd0a558SYan, Zheng rc->search_start = key.objectid; 39023fd0a558SYan, Zheng } 39035d4f98a2SYan Zheng } 39045d4f98a2SYan Zheng 39053a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 39062ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 39073fd0a558SYan, Zheng trans = NULL; 39085d4f98a2SYan Zheng 39095d4f98a2SYan Zheng if (rc->stage == MOVE_DATA_EXTENTS && 39105d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 39115d4f98a2SYan Zheng rc->found_file_extent = 1; 39120257bb82SYan, Zheng ret = relocate_data_extent(rc->data_inode, 39133fd0a558SYan, Zheng &key, &rc->cluster); 39145d4f98a2SYan Zheng if (ret < 0) { 39155d4f98a2SYan Zheng err = ret; 39165d4f98a2SYan Zheng break; 39175d4f98a2SYan Zheng } 39185d4f98a2SYan Zheng } 3919f31ea088SQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 3920f31ea088SQu Wenruo err = -ECANCELED; 3921f31ea088SQu Wenruo break; 3922f31ea088SQu Wenruo } 39235d4f98a2SYan Zheng } 3924c87f08caSChris Mason if (trans && progress && err == -ENOSPC) { 392543a7e99dSNikolay Borisov ret = btrfs_force_chunk_alloc(trans, rc->block_group->flags); 39269689457bSShilong Wang if (ret == 1) { 3927c87f08caSChris Mason err = 0; 3928c87f08caSChris Mason progress = 0; 3929c87f08caSChris Mason goto restart; 3930c87f08caSChris Mason } 3931c87f08caSChris Mason } 39323fd0a558SYan, Zheng 3933b3b4aa74SDavid Sterba btrfs_release_path(path); 393491166212SDavid Sterba clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY); 39355d4f98a2SYan Zheng 39365d4f98a2SYan Zheng if (trans) { 39373a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 39382ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 39395d4f98a2SYan Zheng } 39405d4f98a2SYan Zheng 39410257bb82SYan, Zheng if (!err) { 39423fd0a558SYan, Zheng ret = relocate_file_extent_cluster(rc->data_inode, 39433fd0a558SYan, Zheng &rc->cluster); 39440257bb82SYan, Zheng if (ret < 0) 39450257bb82SYan, Zheng err = ret; 39460257bb82SYan, Zheng } 39470257bb82SYan, Zheng 39483fd0a558SYan, Zheng rc->create_reloc_tree = 0; 39493fd0a558SYan, Zheng set_reloc_control(rc); 39500257bb82SYan, Zheng 39513fd0a558SYan, Zheng backref_cache_cleanup(&rc->backref_cache); 395263f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 39535d4f98a2SYan Zheng 39547f913c7cSQu Wenruo /* 39557f913c7cSQu Wenruo * Even in the case when the relocation is cancelled, we should all go 39567f913c7cSQu Wenruo * through prepare_to_merge() and merge_reloc_roots(). 39577f913c7cSQu Wenruo * 39587f913c7cSQu Wenruo * For error (including cancelled balance), prepare_to_merge() will 39597f913c7cSQu Wenruo * mark all reloc trees orphan, then queue them for cleanup in 39607f913c7cSQu Wenruo * merge_reloc_roots() 39617f913c7cSQu Wenruo */ 39623fd0a558SYan, Zheng err = prepare_to_merge(rc, err); 39635d4f98a2SYan Zheng 39645d4f98a2SYan Zheng merge_reloc_roots(rc); 39655d4f98a2SYan Zheng 39663fd0a558SYan, Zheng rc->merge_reloc_tree = 0; 39675d4f98a2SYan Zheng unset_reloc_control(rc); 396863f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 39695d4f98a2SYan Zheng 39705d4f98a2SYan Zheng /* get rid of pinned extents */ 39717a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 397262b99540SQu Wenruo if (IS_ERR(trans)) { 39733612b495STsutomu Itoh err = PTR_ERR(trans); 397462b99540SQu Wenruo goto out_free; 397562b99540SQu Wenruo } 39763a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 39776217b0faSJosef Bacik out_free: 3978d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 3979d2311e69SQu Wenruo if (ret < 0 && !err) 3980d2311e69SQu Wenruo err = ret; 39812ff7e61eSJeff Mahoney btrfs_free_block_rsv(fs_info, rc->block_rsv); 39823fd0a558SYan, Zheng btrfs_free_path(path); 39835d4f98a2SYan Zheng return err; 39845d4f98a2SYan Zheng } 39855d4f98a2SYan Zheng 39865d4f98a2SYan Zheng static int __insert_orphan_inode(struct btrfs_trans_handle *trans, 39870257bb82SYan, Zheng struct btrfs_root *root, u64 objectid) 39885d4f98a2SYan Zheng { 39895d4f98a2SYan Zheng struct btrfs_path *path; 39905d4f98a2SYan Zheng struct btrfs_inode_item *item; 39915d4f98a2SYan Zheng struct extent_buffer *leaf; 39925d4f98a2SYan Zheng int ret; 39935d4f98a2SYan Zheng 39945d4f98a2SYan Zheng path = btrfs_alloc_path(); 39955d4f98a2SYan Zheng if (!path) 39965d4f98a2SYan Zheng return -ENOMEM; 39975d4f98a2SYan Zheng 39985d4f98a2SYan Zheng ret = btrfs_insert_empty_inode(trans, root, path, objectid); 39995d4f98a2SYan Zheng if (ret) 40005d4f98a2SYan Zheng goto out; 40015d4f98a2SYan Zheng 40025d4f98a2SYan Zheng leaf = path->nodes[0]; 40035d4f98a2SYan Zheng item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); 4004b159fa28SDavid Sterba memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item)); 40055d4f98a2SYan Zheng btrfs_set_inode_generation(leaf, item, 1); 40060257bb82SYan, Zheng btrfs_set_inode_size(leaf, item, 0); 40075d4f98a2SYan Zheng btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); 40083fd0a558SYan, Zheng btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS | 40093fd0a558SYan, Zheng BTRFS_INODE_PREALLOC); 40105d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 40115d4f98a2SYan Zheng out: 40125d4f98a2SYan Zheng btrfs_free_path(path); 40135d4f98a2SYan Zheng return ret; 40145d4f98a2SYan Zheng } 40155d4f98a2SYan Zheng 40165d4f98a2SYan Zheng /* 40175d4f98a2SYan Zheng * helper to create inode for data relocation. 40185d4f98a2SYan Zheng * the inode is in data relocation tree and its link count is 0 40195d4f98a2SYan Zheng */ 40203fd0a558SYan, Zheng static noinline_for_stack 40213fd0a558SYan, Zheng struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, 402232da5386SDavid Sterba struct btrfs_block_group *group) 40235d4f98a2SYan Zheng { 40245d4f98a2SYan Zheng struct inode *inode = NULL; 40255d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 40265d4f98a2SYan Zheng struct btrfs_root *root; 40275d4f98a2SYan Zheng struct btrfs_key key; 40284624900dSZhaolei u64 objectid; 40295d4f98a2SYan Zheng int err = 0; 40305d4f98a2SYan Zheng 40315d4f98a2SYan Zheng root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 40325d4f98a2SYan Zheng if (IS_ERR(root)) 40335d4f98a2SYan Zheng return ERR_CAST(root); 40345d4f98a2SYan Zheng 4035a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 6); 403676deacf0SJosef Bacik if (IS_ERR(trans)) { 403700246528SJosef Bacik btrfs_put_root(root); 40383fd0a558SYan, Zheng return ERR_CAST(trans); 403976deacf0SJosef Bacik } 40405d4f98a2SYan Zheng 4041581bb050SLi Zefan err = btrfs_find_free_objectid(root, &objectid); 40425d4f98a2SYan Zheng if (err) 40435d4f98a2SYan Zheng goto out; 40445d4f98a2SYan Zheng 40450257bb82SYan, Zheng err = __insert_orphan_inode(trans, root, objectid); 40465d4f98a2SYan Zheng BUG_ON(err); 40475d4f98a2SYan Zheng 40485d4f98a2SYan Zheng key.objectid = objectid; 40495d4f98a2SYan Zheng key.type = BTRFS_INODE_ITEM_KEY; 40505d4f98a2SYan Zheng key.offset = 0; 40514c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 40522e19f1f9SAl Viro BUG_ON(IS_ERR(inode)); 4053b3470b5dSDavid Sterba BTRFS_I(inode)->index_cnt = group->start; 40545d4f98a2SYan Zheng 405573f2e545SNikolay Borisov err = btrfs_orphan_add(trans, BTRFS_I(inode)); 40565d4f98a2SYan Zheng out: 405700246528SJosef Bacik btrfs_put_root(root); 40583a45bb20SJeff Mahoney btrfs_end_transaction(trans); 40592ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 40605d4f98a2SYan Zheng if (err) { 40615d4f98a2SYan Zheng if (inode) 40625d4f98a2SYan Zheng iput(inode); 40635d4f98a2SYan Zheng inode = ERR_PTR(err); 40645d4f98a2SYan Zheng } 40655d4f98a2SYan Zheng return inode; 40665d4f98a2SYan Zheng } 40675d4f98a2SYan Zheng 4068c258d6e3SQu Wenruo static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info) 40693fd0a558SYan, Zheng { 40703fd0a558SYan, Zheng struct reloc_control *rc; 40713fd0a558SYan, Zheng 40723fd0a558SYan, Zheng rc = kzalloc(sizeof(*rc), GFP_NOFS); 40733fd0a558SYan, Zheng if (!rc) 40743fd0a558SYan, Zheng return NULL; 40753fd0a558SYan, Zheng 40763fd0a558SYan, Zheng INIT_LIST_HEAD(&rc->reloc_roots); 4077d2311e69SQu Wenruo INIT_LIST_HEAD(&rc->dirty_subvol_roots); 4078584fb121SQu Wenruo btrfs_backref_init_cache(fs_info, &rc->backref_cache, 1); 40793fd0a558SYan, Zheng mapping_tree_init(&rc->reloc_root_tree); 408043eb5f29SQu Wenruo extent_io_tree_init(fs_info, &rc->processed_blocks, 408143eb5f29SQu Wenruo IO_TREE_RELOC_BLOCKS, NULL); 40823fd0a558SYan, Zheng return rc; 40833fd0a558SYan, Zheng } 40843fd0a558SYan, Zheng 40851a0afa0eSJosef Bacik static void free_reloc_control(struct reloc_control *rc) 40861a0afa0eSJosef Bacik { 40871a0afa0eSJosef Bacik struct mapping_node *node, *tmp; 40881a0afa0eSJosef Bacik 40891a0afa0eSJosef Bacik free_reloc_roots(&rc->reloc_roots); 40901a0afa0eSJosef Bacik rbtree_postorder_for_each_entry_safe(node, tmp, 40911a0afa0eSJosef Bacik &rc->reloc_root_tree.rb_root, rb_node) 40921a0afa0eSJosef Bacik kfree(node); 40931a0afa0eSJosef Bacik 40941a0afa0eSJosef Bacik kfree(rc); 40951a0afa0eSJosef Bacik } 40961a0afa0eSJosef Bacik 40975d4f98a2SYan Zheng /* 4098ebce0e01SAdam Borowski * Print the block group being relocated 4099ebce0e01SAdam Borowski */ 4100ebce0e01SAdam Borowski static void describe_relocation(struct btrfs_fs_info *fs_info, 410132da5386SDavid Sterba struct btrfs_block_group *block_group) 4102ebce0e01SAdam Borowski { 4103f89e09cfSAnand Jain char buf[128] = {'\0'}; 4104ebce0e01SAdam Borowski 4105f89e09cfSAnand Jain btrfs_describe_block_groups(block_group->flags, buf, sizeof(buf)); 4106ebce0e01SAdam Borowski 4107ebce0e01SAdam Borowski btrfs_info(fs_info, 4108ebce0e01SAdam Borowski "relocating block group %llu flags %s", 4109b3470b5dSDavid Sterba block_group->start, buf); 4110ebce0e01SAdam Borowski } 4111ebce0e01SAdam Borowski 4112430640e3SQu Wenruo static const char *stage_to_string(int stage) 4113430640e3SQu Wenruo { 4114430640e3SQu Wenruo if (stage == MOVE_DATA_EXTENTS) 4115430640e3SQu Wenruo return "move data extents"; 4116430640e3SQu Wenruo if (stage == UPDATE_DATA_PTRS) 4117430640e3SQu Wenruo return "update data pointers"; 4118430640e3SQu Wenruo return "unknown"; 4119430640e3SQu Wenruo } 4120430640e3SQu Wenruo 4121ebce0e01SAdam Borowski /* 41225d4f98a2SYan Zheng * function to relocate all extents in a block group. 41235d4f98a2SYan Zheng */ 41246bccf3abSJeff Mahoney int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start) 41255d4f98a2SYan Zheng { 412632da5386SDavid Sterba struct btrfs_block_group *bg; 41276bccf3abSJeff Mahoney struct btrfs_root *extent_root = fs_info->extent_root; 41285d4f98a2SYan Zheng struct reloc_control *rc; 41290af3d00bSJosef Bacik struct inode *inode; 41300af3d00bSJosef Bacik struct btrfs_path *path; 41315d4f98a2SYan Zheng int ret; 4132f0486c68SYan, Zheng int rw = 0; 41335d4f98a2SYan Zheng int err = 0; 41345d4f98a2SYan Zheng 4135eede2bf3SOmar Sandoval bg = btrfs_lookup_block_group(fs_info, group_start); 4136eede2bf3SOmar Sandoval if (!bg) 4137eede2bf3SOmar Sandoval return -ENOENT; 4138eede2bf3SOmar Sandoval 4139eede2bf3SOmar Sandoval if (btrfs_pinned_by_swapfile(fs_info, bg)) { 4140eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 4141eede2bf3SOmar Sandoval return -ETXTBSY; 4142eede2bf3SOmar Sandoval } 4143eede2bf3SOmar Sandoval 4144c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 4145eede2bf3SOmar Sandoval if (!rc) { 4146eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 41475d4f98a2SYan Zheng return -ENOMEM; 4148eede2bf3SOmar Sandoval } 41495d4f98a2SYan Zheng 4150f0486c68SYan, Zheng rc->extent_root = extent_root; 4151eede2bf3SOmar Sandoval rc->block_group = bg; 41525d4f98a2SYan Zheng 4153b12de528SQu Wenruo ret = btrfs_inc_block_group_ro(rc->block_group, true); 4154f0486c68SYan, Zheng if (ret) { 4155f0486c68SYan, Zheng err = ret; 4156f0486c68SYan, Zheng goto out; 4157f0486c68SYan, Zheng } 4158f0486c68SYan, Zheng rw = 1; 4159f0486c68SYan, Zheng 41600af3d00bSJosef Bacik path = btrfs_alloc_path(); 41610af3d00bSJosef Bacik if (!path) { 41620af3d00bSJosef Bacik err = -ENOMEM; 41630af3d00bSJosef Bacik goto out; 41640af3d00bSJosef Bacik } 41650af3d00bSJosef Bacik 41667949f339SDavid Sterba inode = lookup_free_space_inode(rc->block_group, path); 41670af3d00bSJosef Bacik btrfs_free_path(path); 41680af3d00bSJosef Bacik 41690af3d00bSJosef Bacik if (!IS_ERR(inode)) 41701bbc621eSChris Mason ret = delete_block_group_cache(fs_info, rc->block_group, inode, 0); 41710af3d00bSJosef Bacik else 41720af3d00bSJosef Bacik ret = PTR_ERR(inode); 41730af3d00bSJosef Bacik 41740af3d00bSJosef Bacik if (ret && ret != -ENOENT) { 41750af3d00bSJosef Bacik err = ret; 41760af3d00bSJosef Bacik goto out; 41770af3d00bSJosef Bacik } 41780af3d00bSJosef Bacik 41795d4f98a2SYan Zheng rc->data_inode = create_reloc_inode(fs_info, rc->block_group); 41805d4f98a2SYan Zheng if (IS_ERR(rc->data_inode)) { 41815d4f98a2SYan Zheng err = PTR_ERR(rc->data_inode); 41825d4f98a2SYan Zheng rc->data_inode = NULL; 41835d4f98a2SYan Zheng goto out; 41845d4f98a2SYan Zheng } 41855d4f98a2SYan Zheng 41860b246afaSJeff Mahoney describe_relocation(fs_info, rc->block_group); 41875d4f98a2SYan Zheng 41889cfa3e34SFilipe Manana btrfs_wait_block_group_reservations(rc->block_group); 4189f78c436cSFilipe Manana btrfs_wait_nocow_writers(rc->block_group); 41906374e57aSChris Mason btrfs_wait_ordered_roots(fs_info, U64_MAX, 4191b3470b5dSDavid Sterba rc->block_group->start, 4192b3470b5dSDavid Sterba rc->block_group->length); 41935d4f98a2SYan Zheng 41945d4f98a2SYan Zheng while (1) { 4195430640e3SQu Wenruo int finishes_stage; 4196430640e3SQu Wenruo 419776dda93cSYan, Zheng mutex_lock(&fs_info->cleaner_mutex); 41985d4f98a2SYan Zheng ret = relocate_block_group(rc); 419976dda93cSYan, Zheng mutex_unlock(&fs_info->cleaner_mutex); 4200ff612ba7SJosef Bacik if (ret < 0) 42015d4f98a2SYan Zheng err = ret; 4202ff612ba7SJosef Bacik 4203430640e3SQu Wenruo finishes_stage = rc->stage; 4204ff612ba7SJosef Bacik /* 4205ff612ba7SJosef Bacik * We may have gotten ENOSPC after we already dirtied some 4206ff612ba7SJosef Bacik * extents. If writeout happens while we're relocating a 4207ff612ba7SJosef Bacik * different block group we could end up hitting the 4208ff612ba7SJosef Bacik * BUG_ON(rc->stage == UPDATE_DATA_PTRS) in 4209ff612ba7SJosef Bacik * btrfs_reloc_cow_block. Make sure we write everything out 4210ff612ba7SJosef Bacik * properly so we don't trip over this problem, and then break 4211ff612ba7SJosef Bacik * out of the loop if we hit an error. 4212ff612ba7SJosef Bacik */ 4213ff612ba7SJosef Bacik if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { 4214ff612ba7SJosef Bacik ret = btrfs_wait_ordered_range(rc->data_inode, 0, 4215ff612ba7SJosef Bacik (u64)-1); 4216ff612ba7SJosef Bacik if (ret) 4217ff612ba7SJosef Bacik err = ret; 4218ff612ba7SJosef Bacik invalidate_mapping_pages(rc->data_inode->i_mapping, 4219ff612ba7SJosef Bacik 0, -1); 4220ff612ba7SJosef Bacik rc->stage = UPDATE_DATA_PTRS; 42215d4f98a2SYan Zheng } 42225d4f98a2SYan Zheng 4223ff612ba7SJosef Bacik if (err < 0) 4224ff612ba7SJosef Bacik goto out; 4225ff612ba7SJosef Bacik 42265d4f98a2SYan Zheng if (rc->extents_found == 0) 42275d4f98a2SYan Zheng break; 42285d4f98a2SYan Zheng 4229430640e3SQu Wenruo btrfs_info(fs_info, "found %llu extents, stage: %s", 4230430640e3SQu Wenruo rc->extents_found, stage_to_string(finishes_stage)); 42315d4f98a2SYan Zheng } 42325d4f98a2SYan Zheng 42335d4f98a2SYan Zheng WARN_ON(rc->block_group->pinned > 0); 42345d4f98a2SYan Zheng WARN_ON(rc->block_group->reserved > 0); 4235bf38be65SDavid Sterba WARN_ON(rc->block_group->used > 0); 42365d4f98a2SYan Zheng out: 4237f0486c68SYan, Zheng if (err && rw) 42382ff7e61eSJeff Mahoney btrfs_dec_block_group_ro(rc->block_group); 42395d4f98a2SYan Zheng iput(rc->data_inode); 42405d4f98a2SYan Zheng btrfs_put_block_group(rc->block_group); 42411a0afa0eSJosef Bacik free_reloc_control(rc); 42425d4f98a2SYan Zheng return err; 42435d4f98a2SYan Zheng } 42445d4f98a2SYan Zheng 424576dda93cSYan, Zheng static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) 424676dda93cSYan, Zheng { 42470b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 424876dda93cSYan, Zheng struct btrfs_trans_handle *trans; 424979787eaaSJeff Mahoney int ret, err; 425076dda93cSYan, Zheng 42510b246afaSJeff Mahoney trans = btrfs_start_transaction(fs_info->tree_root, 0); 425279787eaaSJeff Mahoney if (IS_ERR(trans)) 425379787eaaSJeff Mahoney return PTR_ERR(trans); 425476dda93cSYan, Zheng 425576dda93cSYan, Zheng memset(&root->root_item.drop_progress, 0, 425676dda93cSYan, Zheng sizeof(root->root_item.drop_progress)); 425776dda93cSYan, Zheng root->root_item.drop_level = 0; 425876dda93cSYan, Zheng btrfs_set_root_refs(&root->root_item, 0); 42590b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 426076dda93cSYan, Zheng &root->root_key, &root->root_item); 426176dda93cSYan, Zheng 42623a45bb20SJeff Mahoney err = btrfs_end_transaction(trans); 426379787eaaSJeff Mahoney if (err) 426479787eaaSJeff Mahoney return err; 426579787eaaSJeff Mahoney return ret; 426676dda93cSYan, Zheng } 426776dda93cSYan, Zheng 42685d4f98a2SYan Zheng /* 42695d4f98a2SYan Zheng * recover relocation interrupted by system crash. 42705d4f98a2SYan Zheng * 42715d4f98a2SYan Zheng * this function resumes merging reloc trees with corresponding fs trees. 42725d4f98a2SYan Zheng * this is important for keeping the sharing of tree blocks 42735d4f98a2SYan Zheng */ 42745d4f98a2SYan Zheng int btrfs_recover_relocation(struct btrfs_root *root) 42755d4f98a2SYan Zheng { 42760b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 42775d4f98a2SYan Zheng LIST_HEAD(reloc_roots); 42785d4f98a2SYan Zheng struct btrfs_key key; 42795d4f98a2SYan Zheng struct btrfs_root *fs_root; 42805d4f98a2SYan Zheng struct btrfs_root *reloc_root; 42815d4f98a2SYan Zheng struct btrfs_path *path; 42825d4f98a2SYan Zheng struct extent_buffer *leaf; 42835d4f98a2SYan Zheng struct reloc_control *rc = NULL; 42845d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 42855d4f98a2SYan Zheng int ret; 42865d4f98a2SYan Zheng int err = 0; 42875d4f98a2SYan Zheng 42885d4f98a2SYan Zheng path = btrfs_alloc_path(); 42895d4f98a2SYan Zheng if (!path) 42905d4f98a2SYan Zheng return -ENOMEM; 4291e4058b54SDavid Sterba path->reada = READA_BACK; 42925d4f98a2SYan Zheng 42935d4f98a2SYan Zheng key.objectid = BTRFS_TREE_RELOC_OBJECTID; 42945d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 42955d4f98a2SYan Zheng key.offset = (u64)-1; 42965d4f98a2SYan Zheng 42975d4f98a2SYan Zheng while (1) { 42980b246afaSJeff Mahoney ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, 42995d4f98a2SYan Zheng path, 0, 0); 43005d4f98a2SYan Zheng if (ret < 0) { 43015d4f98a2SYan Zheng err = ret; 43025d4f98a2SYan Zheng goto out; 43035d4f98a2SYan Zheng } 43045d4f98a2SYan Zheng if (ret > 0) { 43055d4f98a2SYan Zheng if (path->slots[0] == 0) 43065d4f98a2SYan Zheng break; 43075d4f98a2SYan Zheng path->slots[0]--; 43085d4f98a2SYan Zheng } 43095d4f98a2SYan Zheng leaf = path->nodes[0]; 43105d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4311b3b4aa74SDavid Sterba btrfs_release_path(path); 43125d4f98a2SYan Zheng 43135d4f98a2SYan Zheng if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || 43145d4f98a2SYan Zheng key.type != BTRFS_ROOT_ITEM_KEY) 43155d4f98a2SYan Zheng break; 43165d4f98a2SYan Zheng 43173dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(root, &key); 43185d4f98a2SYan Zheng if (IS_ERR(reloc_root)) { 43195d4f98a2SYan Zheng err = PTR_ERR(reloc_root); 43205d4f98a2SYan Zheng goto out; 43215d4f98a2SYan Zheng } 43225d4f98a2SYan Zheng 43233dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 43245d4f98a2SYan Zheng list_add(&reloc_root->root_list, &reloc_roots); 43255d4f98a2SYan Zheng 43265d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 43270b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, 43285d4f98a2SYan Zheng reloc_root->root_key.offset); 43295d4f98a2SYan Zheng if (IS_ERR(fs_root)) { 433076dda93cSYan, Zheng ret = PTR_ERR(fs_root); 433176dda93cSYan, Zheng if (ret != -ENOENT) { 433276dda93cSYan, Zheng err = ret; 43335d4f98a2SYan Zheng goto out; 43345d4f98a2SYan Zheng } 433579787eaaSJeff Mahoney ret = mark_garbage_root(reloc_root); 433679787eaaSJeff Mahoney if (ret < 0) { 433779787eaaSJeff Mahoney err = ret; 433879787eaaSJeff Mahoney goto out; 433979787eaaSJeff Mahoney } 4340932fd26dSJosef Bacik } else { 434100246528SJosef Bacik btrfs_put_root(fs_root); 434276dda93cSYan, Zheng } 43435d4f98a2SYan Zheng } 43445d4f98a2SYan Zheng 43455d4f98a2SYan Zheng if (key.offset == 0) 43465d4f98a2SYan Zheng break; 43475d4f98a2SYan Zheng 43485d4f98a2SYan Zheng key.offset--; 43495d4f98a2SYan Zheng } 4350b3b4aa74SDavid Sterba btrfs_release_path(path); 43515d4f98a2SYan Zheng 43525d4f98a2SYan Zheng if (list_empty(&reloc_roots)) 43535d4f98a2SYan Zheng goto out; 43545d4f98a2SYan Zheng 4355c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 43565d4f98a2SYan Zheng if (!rc) { 43575d4f98a2SYan Zheng err = -ENOMEM; 43585d4f98a2SYan Zheng goto out; 43595d4f98a2SYan Zheng } 43605d4f98a2SYan Zheng 43610b246afaSJeff Mahoney rc->extent_root = fs_info->extent_root; 43625d4f98a2SYan Zheng 43635d4f98a2SYan Zheng set_reloc_control(rc); 43645d4f98a2SYan Zheng 43657a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 43663612b495STsutomu Itoh if (IS_ERR(trans)) { 43673612b495STsutomu Itoh err = PTR_ERR(trans); 4368fb2d83eeSJosef Bacik goto out_unset; 43693612b495STsutomu Itoh } 43703fd0a558SYan, Zheng 43713fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 43723fd0a558SYan, Zheng 43735d4f98a2SYan Zheng while (!list_empty(&reloc_roots)) { 43745d4f98a2SYan Zheng reloc_root = list_entry(reloc_roots.next, 43755d4f98a2SYan Zheng struct btrfs_root, root_list); 43765d4f98a2SYan Zheng list_del(&reloc_root->root_list); 43775d4f98a2SYan Zheng 43785d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) == 0) { 43795d4f98a2SYan Zheng list_add_tail(&reloc_root->root_list, 43805d4f98a2SYan Zheng &rc->reloc_roots); 43815d4f98a2SYan Zheng continue; 43825d4f98a2SYan Zheng } 43835d4f98a2SYan Zheng 43840b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, reloc_root->root_key.offset); 438579787eaaSJeff Mahoney if (IS_ERR(fs_root)) { 438679787eaaSJeff Mahoney err = PTR_ERR(fs_root); 4387ca1aa281SJosef Bacik list_add_tail(&reloc_root->root_list, &reloc_roots); 43881402d17dSXiyu Yang btrfs_end_transaction(trans); 4389fb2d83eeSJosef Bacik goto out_unset; 439079787eaaSJeff Mahoney } 43915d4f98a2SYan Zheng 4392ffd7b339SJeff Mahoney err = __add_reloc_root(reloc_root); 439379787eaaSJeff Mahoney BUG_ON(err < 0); /* -ENOMEM or logic error */ 4394f44deb74SJosef Bacik fs_root->reloc_root = btrfs_grab_root(reloc_root); 439500246528SJosef Bacik btrfs_put_root(fs_root); 43965d4f98a2SYan Zheng } 43975d4f98a2SYan Zheng 43983a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 439979787eaaSJeff Mahoney if (err) 4400fb2d83eeSJosef Bacik goto out_unset; 44015d4f98a2SYan Zheng 44025d4f98a2SYan Zheng merge_reloc_roots(rc); 44035d4f98a2SYan Zheng 44045d4f98a2SYan Zheng unset_reloc_control(rc); 44055d4f98a2SYan Zheng 44067a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 440762b99540SQu Wenruo if (IS_ERR(trans)) { 44083612b495STsutomu Itoh err = PTR_ERR(trans); 44096217b0faSJosef Bacik goto out_clean; 441062b99540SQu Wenruo } 44113a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 44126217b0faSJosef Bacik out_clean: 4413d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 4414d2311e69SQu Wenruo if (ret < 0 && !err) 4415d2311e69SQu Wenruo err = ret; 4416fb2d83eeSJosef Bacik out_unset: 4417fb2d83eeSJosef Bacik unset_reloc_control(rc); 44181a0afa0eSJosef Bacik free_reloc_control(rc); 44193612b495STsutomu Itoh out: 4420aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 4421aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 4422aca1bba6SLiu Bo 44235d4f98a2SYan Zheng btrfs_free_path(path); 44245d4f98a2SYan Zheng 44255d4f98a2SYan Zheng if (err == 0) { 44265d4f98a2SYan Zheng /* cleanup orphan inode in data relocation tree */ 44270b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 4428932fd26dSJosef Bacik if (IS_ERR(fs_root)) { 44295d4f98a2SYan Zheng err = PTR_ERR(fs_root); 4430932fd26dSJosef Bacik } else { 443166b4ffd1SJosef Bacik err = btrfs_orphan_cleanup(fs_root); 443200246528SJosef Bacik btrfs_put_root(fs_root); 4433932fd26dSJosef Bacik } 4434932fd26dSJosef Bacik } 44355d4f98a2SYan Zheng return err; 44365d4f98a2SYan Zheng } 44375d4f98a2SYan Zheng 44385d4f98a2SYan Zheng /* 44395d4f98a2SYan Zheng * helper to add ordered checksum for data relocation. 44405d4f98a2SYan Zheng * 44415d4f98a2SYan Zheng * cloning checksum properly handles the nodatasum extents. 44425d4f98a2SYan Zheng * it also saves CPU time to re-calculate the checksum. 44435d4f98a2SYan Zheng */ 44445d4f98a2SYan Zheng int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) 44455d4f98a2SYan Zheng { 44460b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 44475d4f98a2SYan Zheng struct btrfs_ordered_sum *sums; 44485d4f98a2SYan Zheng struct btrfs_ordered_extent *ordered; 44495d4f98a2SYan Zheng int ret; 44505d4f98a2SYan Zheng u64 disk_bytenr; 44514577b014SJosef Bacik u64 new_bytenr; 44525d4f98a2SYan Zheng LIST_HEAD(list); 44535d4f98a2SYan Zheng 44545d4f98a2SYan Zheng ordered = btrfs_lookup_ordered_extent(inode, file_pos); 4455bffe633eSOmar Sandoval BUG_ON(ordered->file_offset != file_pos || ordered->num_bytes != len); 44565d4f98a2SYan Zheng 44575d4f98a2SYan Zheng disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; 44580b246afaSJeff Mahoney ret = btrfs_lookup_csums_range(fs_info->csum_root, disk_bytenr, 4459a2de733cSArne Jansen disk_bytenr + len - 1, &list, 0); 446079787eaaSJeff Mahoney if (ret) 446179787eaaSJeff Mahoney goto out; 44625d4f98a2SYan Zheng 44635d4f98a2SYan Zheng while (!list_empty(&list)) { 44645d4f98a2SYan Zheng sums = list_entry(list.next, struct btrfs_ordered_sum, list); 44655d4f98a2SYan Zheng list_del_init(&sums->list); 44665d4f98a2SYan Zheng 44674577b014SJosef Bacik /* 44684577b014SJosef Bacik * We need to offset the new_bytenr based on where the csum is. 44694577b014SJosef Bacik * We need to do this because we will read in entire prealloc 44704577b014SJosef Bacik * extents but we may have written to say the middle of the 44714577b014SJosef Bacik * prealloc extent, so we need to make sure the csum goes with 44724577b014SJosef Bacik * the right disk offset. 44734577b014SJosef Bacik * 44744577b014SJosef Bacik * We can do this because the data reloc inode refers strictly 44754577b014SJosef Bacik * to the on disk bytes, so we don't have to worry about 44764577b014SJosef Bacik * disk_len vs real len like with real inodes since it's all 44774577b014SJosef Bacik * disk length. 44784577b014SJosef Bacik */ 4479bffe633eSOmar Sandoval new_bytenr = ordered->disk_bytenr + sums->bytenr - disk_bytenr; 44804577b014SJosef Bacik sums->bytenr = new_bytenr; 44815d4f98a2SYan Zheng 4482f9756261SNikolay Borisov btrfs_add_ordered_sum(ordered, sums); 44835d4f98a2SYan Zheng } 448479787eaaSJeff Mahoney out: 44855d4f98a2SYan Zheng btrfs_put_ordered_extent(ordered); 4486411fc6bcSAndi Kleen return ret; 44875d4f98a2SYan Zheng } 44883fd0a558SYan, Zheng 448983d4cfd4SJosef Bacik int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, 44903fd0a558SYan, Zheng struct btrfs_root *root, struct extent_buffer *buf, 44913fd0a558SYan, Zheng struct extent_buffer *cow) 44923fd0a558SYan, Zheng { 44930b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 44943fd0a558SYan, Zheng struct reloc_control *rc; 4495a26195a5SQu Wenruo struct btrfs_backref_node *node; 44963fd0a558SYan, Zheng int first_cow = 0; 44973fd0a558SYan, Zheng int level; 449883d4cfd4SJosef Bacik int ret = 0; 44993fd0a558SYan, Zheng 45000b246afaSJeff Mahoney rc = fs_info->reloc_ctl; 45013fd0a558SYan, Zheng if (!rc) 450283d4cfd4SJosef Bacik return 0; 45033fd0a558SYan, Zheng 45043fd0a558SYan, Zheng BUG_ON(rc->stage == UPDATE_DATA_PTRS && 45053fd0a558SYan, Zheng root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID); 45063fd0a558SYan, Zheng 45073fd0a558SYan, Zheng level = btrfs_header_level(buf); 45083fd0a558SYan, Zheng if (btrfs_header_generation(buf) <= 45093fd0a558SYan, Zheng btrfs_root_last_snapshot(&root->root_item)) 45103fd0a558SYan, Zheng first_cow = 1; 45113fd0a558SYan, Zheng 45123fd0a558SYan, Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID && 45133fd0a558SYan, Zheng rc->create_reloc_tree) { 45143fd0a558SYan, Zheng WARN_ON(!first_cow && level == 0); 45153fd0a558SYan, Zheng 45163fd0a558SYan, Zheng node = rc->backref_cache.path[level]; 45173fd0a558SYan, Zheng BUG_ON(node->bytenr != buf->start && 45183fd0a558SYan, Zheng node->new_bytenr != buf->start); 45193fd0a558SYan, Zheng 4520b0fe7078SQu Wenruo btrfs_backref_drop_node_buffer(node); 452167439dadSDavid Sterba atomic_inc(&cow->refs); 45223fd0a558SYan, Zheng node->eb = cow; 45233fd0a558SYan, Zheng node->new_bytenr = cow->start; 45243fd0a558SYan, Zheng 45253fd0a558SYan, Zheng if (!node->pending) { 45263fd0a558SYan, Zheng list_move_tail(&node->list, 45273fd0a558SYan, Zheng &rc->backref_cache.pending[level]); 45283fd0a558SYan, Zheng node->pending = 1; 45293fd0a558SYan, Zheng } 45303fd0a558SYan, Zheng 45313fd0a558SYan, Zheng if (first_cow) 45329569cc20SQu Wenruo mark_block_processed(rc, node); 45333fd0a558SYan, Zheng 45343fd0a558SYan, Zheng if (first_cow && level > 0) 45353fd0a558SYan, Zheng rc->nodes_relocated += buf->len; 45363fd0a558SYan, Zheng } 45373fd0a558SYan, Zheng 453883d4cfd4SJosef Bacik if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) 45393fd0a558SYan, Zheng ret = replace_file_extents(trans, rc, root, cow); 454083d4cfd4SJosef Bacik return ret; 45413fd0a558SYan, Zheng } 45423fd0a558SYan, Zheng 45433fd0a558SYan, Zheng /* 45443fd0a558SYan, Zheng * called before creating snapshot. it calculates metadata reservation 454501327610SNicholas D Steeves * required for relocating tree blocks in the snapshot 45463fd0a558SYan, Zheng */ 4547147d256eSZhaolei void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending, 45483fd0a558SYan, Zheng u64 *bytes_to_reserve) 45493fd0a558SYan, Zheng { 455010995c04SQu Wenruo struct btrfs_root *root = pending->root; 455110995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 45523fd0a558SYan, Zheng 45536282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 45543fd0a558SYan, Zheng return; 45553fd0a558SYan, Zheng 45563fd0a558SYan, Zheng if (!rc->merge_reloc_tree) 45573fd0a558SYan, Zheng return; 45583fd0a558SYan, Zheng 45593fd0a558SYan, Zheng root = root->reloc_root; 45603fd0a558SYan, Zheng BUG_ON(btrfs_root_refs(&root->root_item) == 0); 45613fd0a558SYan, Zheng /* 45623fd0a558SYan, Zheng * relocation is in the stage of merging trees. the space 45633fd0a558SYan, Zheng * used by merging a reloc tree is twice the size of 45643fd0a558SYan, Zheng * relocated tree nodes in the worst case. half for cowing 45653fd0a558SYan, Zheng * the reloc tree, half for cowing the fs tree. the space 45663fd0a558SYan, Zheng * used by cowing the reloc tree will be freed after the 45673fd0a558SYan, Zheng * tree is dropped. if we create snapshot, cowing the fs 45683fd0a558SYan, Zheng * tree may use more space than it frees. so we need 45693fd0a558SYan, Zheng * reserve extra space. 45703fd0a558SYan, Zheng */ 45713fd0a558SYan, Zheng *bytes_to_reserve += rc->nodes_relocated; 45723fd0a558SYan, Zheng } 45733fd0a558SYan, Zheng 45743fd0a558SYan, Zheng /* 45753fd0a558SYan, Zheng * called after snapshot is created. migrate block reservation 45763fd0a558SYan, Zheng * and create reloc root for the newly created snapshot 4577f44deb74SJosef Bacik * 4578f44deb74SJosef Bacik * This is similar to btrfs_init_reloc_root(), we come out of here with two 4579f44deb74SJosef Bacik * references held on the reloc_root, one for root->reloc_root and one for 4580f44deb74SJosef Bacik * rc->reloc_roots. 45813fd0a558SYan, Zheng */ 458249b25e05SJeff Mahoney int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, 45833fd0a558SYan, Zheng struct btrfs_pending_snapshot *pending) 45843fd0a558SYan, Zheng { 45853fd0a558SYan, Zheng struct btrfs_root *root = pending->root; 45863fd0a558SYan, Zheng struct btrfs_root *reloc_root; 45873fd0a558SYan, Zheng struct btrfs_root *new_root; 458810995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 45893fd0a558SYan, Zheng int ret; 45903fd0a558SYan, Zheng 45916282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 459249b25e05SJeff Mahoney return 0; 45933fd0a558SYan, Zheng 45943fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 45953fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated; 45963fd0a558SYan, Zheng 45973fd0a558SYan, Zheng if (rc->merge_reloc_tree) { 45983fd0a558SYan, Zheng ret = btrfs_block_rsv_migrate(&pending->block_rsv, 45993fd0a558SYan, Zheng rc->block_rsv, 46003a584174SLu Fengqi rc->nodes_relocated, true); 460149b25e05SJeff Mahoney if (ret) 460249b25e05SJeff Mahoney return ret; 46033fd0a558SYan, Zheng } 46043fd0a558SYan, Zheng 46053fd0a558SYan, Zheng new_root = pending->snap; 46063fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root->reloc_root, 46073fd0a558SYan, Zheng new_root->root_key.objectid); 460849b25e05SJeff Mahoney if (IS_ERR(reloc_root)) 460949b25e05SJeff Mahoney return PTR_ERR(reloc_root); 46103fd0a558SYan, Zheng 4611ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 4612ffd7b339SJeff Mahoney BUG_ON(ret < 0); 4613f44deb74SJosef Bacik new_root->reloc_root = btrfs_grab_root(reloc_root); 46143fd0a558SYan, Zheng 461549b25e05SJeff Mahoney if (rc->create_reloc_tree) 46163fd0a558SYan, Zheng ret = clone_backref_node(trans, rc, root, reloc_root); 461749b25e05SJeff Mahoney return ret; 46183fd0a558SYan, Zheng } 4619