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 156a26195a5SQu Wenruo static void remove_backref_node(struct btrfs_backref_cache *cache, 157a26195a5SQu Wenruo struct btrfs_backref_node *node); 1589569cc20SQu Wenruo 1599569cc20SQu Wenruo static void mark_block_processed(struct reloc_control *rc, 160a26195a5SQu Wenruo struct btrfs_backref_node *node) 1619569cc20SQu Wenruo { 1629569cc20SQu Wenruo u32 blocksize; 1639569cc20SQu Wenruo 1649569cc20SQu Wenruo if (node->level == 0 || 1659569cc20SQu Wenruo in_range(node->bytenr, rc->block_group->start, 1669569cc20SQu Wenruo rc->block_group->length)) { 1679569cc20SQu Wenruo blocksize = rc->extent_root->fs_info->nodesize; 1689569cc20SQu Wenruo set_extent_bits(&rc->processed_blocks, node->bytenr, 1699569cc20SQu Wenruo node->bytenr + blocksize - 1, EXTENT_DIRTY); 1709569cc20SQu Wenruo } 1719569cc20SQu Wenruo node->processed = 1; 1729569cc20SQu Wenruo } 1739569cc20SQu Wenruo 1745d4f98a2SYan Zheng 1755d4f98a2SYan Zheng static void mapping_tree_init(struct mapping_tree *tree) 1765d4f98a2SYan Zheng { 1776bef4d31SEric Paris tree->rb_root = RB_ROOT; 1785d4f98a2SYan Zheng spin_lock_init(&tree->lock); 1795d4f98a2SYan Zheng } 1805d4f98a2SYan Zheng 181a26195a5SQu Wenruo static void backref_cache_cleanup(struct btrfs_backref_cache *cache) 1825d4f98a2SYan Zheng { 183a26195a5SQu Wenruo struct btrfs_backref_node *node; 1843fd0a558SYan, Zheng int i; 1853fd0a558SYan, Zheng 1863fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 1873fd0a558SYan, Zheng node = list_entry(cache->detached.next, 188a26195a5SQu Wenruo struct btrfs_backref_node, list); 1893fd0a558SYan, Zheng remove_backref_node(cache, node); 1903fd0a558SYan, Zheng } 1913fd0a558SYan, Zheng 1923fd0a558SYan, Zheng while (!list_empty(&cache->leaves)) { 1933fd0a558SYan, Zheng node = list_entry(cache->leaves.next, 194a26195a5SQu Wenruo struct btrfs_backref_node, lower); 1953fd0a558SYan, Zheng remove_backref_node(cache, node); 1963fd0a558SYan, Zheng } 1973fd0a558SYan, Zheng 1983fd0a558SYan, Zheng cache->last_trans = 0; 1993fd0a558SYan, Zheng 2003fd0a558SYan, Zheng for (i = 0; i < BTRFS_MAX_LEVEL; i++) 201f4907095SLiu Bo ASSERT(list_empty(&cache->pending[i])); 20284780289SQu Wenruo ASSERT(list_empty(&cache->pending_edge)); 20384780289SQu Wenruo ASSERT(list_empty(&cache->useless_node)); 204f4907095SLiu Bo ASSERT(list_empty(&cache->changed)); 205f4907095SLiu Bo ASSERT(list_empty(&cache->detached)); 206f4907095SLiu Bo ASSERT(RB_EMPTY_ROOT(&cache->rb_root)); 207f4907095SLiu Bo ASSERT(!cache->nr_nodes); 208f4907095SLiu Bo ASSERT(!cache->nr_edges); 2093fd0a558SYan, Zheng } 2103fd0a558SYan, Zheng 21148a3b636SEric Sandeen static void backref_tree_panic(struct rb_node *rb_node, int errno, u64 bytenr) 21243c04fb1SJeff Mahoney { 21343c04fb1SJeff Mahoney 21443c04fb1SJeff Mahoney struct btrfs_fs_info *fs_info = NULL; 215a26195a5SQu Wenruo struct btrfs_backref_node *bnode = rb_entry(rb_node, 216a26195a5SQu Wenruo struct btrfs_backref_node, rb_node); 21743c04fb1SJeff Mahoney if (bnode->root) 21843c04fb1SJeff Mahoney fs_info = bnode->root->fs_info; 2195d163e0eSJeff Mahoney btrfs_panic(fs_info, errno, 2205d163e0eSJeff Mahoney "Inconsistency in backref cache found at offset %llu", 2215d163e0eSJeff Mahoney bytenr); 22243c04fb1SJeff Mahoney } 22343c04fb1SJeff Mahoney 2245d4f98a2SYan Zheng /* 2255d4f98a2SYan Zheng * walk up backref nodes until reach node presents tree root 2265d4f98a2SYan Zheng */ 227a26195a5SQu Wenruo static struct btrfs_backref_node *walk_up_backref( 228a26195a5SQu Wenruo struct btrfs_backref_node *node, 229a26195a5SQu Wenruo struct btrfs_backref_edge *edges[], int *index) 2305d4f98a2SYan Zheng { 231a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2325d4f98a2SYan Zheng int idx = *index; 2335d4f98a2SYan Zheng 2345d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 2355d4f98a2SYan Zheng edge = list_entry(node->upper.next, 236a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 2375d4f98a2SYan Zheng edges[idx++] = edge; 2385d4f98a2SYan Zheng node = edge->node[UPPER]; 2395d4f98a2SYan Zheng } 2403fd0a558SYan, Zheng BUG_ON(node->detached); 2415d4f98a2SYan Zheng *index = idx; 2425d4f98a2SYan Zheng return node; 2435d4f98a2SYan Zheng } 2445d4f98a2SYan Zheng 2455d4f98a2SYan Zheng /* 2465d4f98a2SYan Zheng * walk down backref nodes to find start of next reference path 2475d4f98a2SYan Zheng */ 248a26195a5SQu Wenruo static struct btrfs_backref_node *walk_down_backref( 249a26195a5SQu Wenruo struct btrfs_backref_edge *edges[], int *index) 2505d4f98a2SYan Zheng { 251a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 252a26195a5SQu Wenruo struct btrfs_backref_node *lower; 2535d4f98a2SYan Zheng int idx = *index; 2545d4f98a2SYan Zheng 2555d4f98a2SYan Zheng while (idx > 0) { 2565d4f98a2SYan Zheng edge = edges[idx - 1]; 2575d4f98a2SYan Zheng lower = edge->node[LOWER]; 2585d4f98a2SYan Zheng if (list_is_last(&edge->list[LOWER], &lower->upper)) { 2595d4f98a2SYan Zheng idx--; 2605d4f98a2SYan Zheng continue; 2615d4f98a2SYan Zheng } 2625d4f98a2SYan Zheng edge = list_entry(edge->list[LOWER].next, 263a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 2645d4f98a2SYan Zheng edges[idx - 1] = edge; 2655d4f98a2SYan Zheng *index = idx; 2665d4f98a2SYan Zheng return edge->node[UPPER]; 2675d4f98a2SYan Zheng } 2685d4f98a2SYan Zheng *index = 0; 2695d4f98a2SYan Zheng return NULL; 2705d4f98a2SYan Zheng } 2715d4f98a2SYan Zheng 272a26195a5SQu Wenruo static void unlock_node_buffer(struct btrfs_backref_node *node) 2735d4f98a2SYan Zheng { 2745d4f98a2SYan Zheng if (node->locked) { 2755d4f98a2SYan Zheng btrfs_tree_unlock(node->eb); 2765d4f98a2SYan Zheng node->locked = 0; 2775d4f98a2SYan Zheng } 2783fd0a558SYan, Zheng } 2793fd0a558SYan, Zheng 280a26195a5SQu Wenruo static void drop_node_buffer(struct btrfs_backref_node *node) 2813fd0a558SYan, Zheng { 2823fd0a558SYan, Zheng if (node->eb) { 2833fd0a558SYan, Zheng unlock_node_buffer(node); 2845d4f98a2SYan Zheng free_extent_buffer(node->eb); 2855d4f98a2SYan Zheng node->eb = NULL; 2865d4f98a2SYan Zheng } 2875d4f98a2SYan Zheng } 2885d4f98a2SYan Zheng 289a26195a5SQu Wenruo static void drop_backref_node(struct btrfs_backref_cache *tree, 290a26195a5SQu Wenruo struct btrfs_backref_node *node) 2915d4f98a2SYan Zheng { 2925d4f98a2SYan Zheng BUG_ON(!list_empty(&node->upper)); 2935d4f98a2SYan Zheng 2945d4f98a2SYan Zheng drop_node_buffer(node); 2953fd0a558SYan, Zheng list_del(&node->list); 2965d4f98a2SYan Zheng list_del(&node->lower); 2973fd0a558SYan, Zheng if (!RB_EMPTY_NODE(&node->rb_node)) 2985d4f98a2SYan Zheng rb_erase(&node->rb_node, &tree->rb_root); 299741188d3SQu Wenruo btrfs_backref_free_node(tree, node); 3005d4f98a2SYan Zheng } 3015d4f98a2SYan Zheng 3025d4f98a2SYan Zheng /* 3035d4f98a2SYan Zheng * remove a backref node from the backref cache 3045d4f98a2SYan Zheng */ 305a26195a5SQu Wenruo static void remove_backref_node(struct btrfs_backref_cache *cache, 306a26195a5SQu Wenruo struct btrfs_backref_node *node) 3075d4f98a2SYan Zheng { 308a26195a5SQu Wenruo struct btrfs_backref_node *upper; 309a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 3105d4f98a2SYan Zheng 3115d4f98a2SYan Zheng if (!node) 3125d4f98a2SYan Zheng return; 3135d4f98a2SYan Zheng 3143fd0a558SYan, Zheng BUG_ON(!node->lowest && !node->detached); 3155d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 316a26195a5SQu Wenruo edge = list_entry(node->upper.next, struct btrfs_backref_edge, 3175d4f98a2SYan Zheng list[LOWER]); 3185d4f98a2SYan Zheng upper = edge->node[UPPER]; 3195d4f98a2SYan Zheng list_del(&edge->list[LOWER]); 3205d4f98a2SYan Zheng list_del(&edge->list[UPPER]); 321741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 3223fd0a558SYan, Zheng 3233fd0a558SYan, Zheng if (RB_EMPTY_NODE(&upper->rb_node)) { 3243fd0a558SYan, Zheng BUG_ON(!list_empty(&node->upper)); 3253fd0a558SYan, Zheng drop_backref_node(cache, node); 3263fd0a558SYan, Zheng node = upper; 3273fd0a558SYan, Zheng node->lowest = 1; 3283fd0a558SYan, Zheng continue; 3293fd0a558SYan, Zheng } 3305d4f98a2SYan Zheng /* 3313fd0a558SYan, Zheng * add the node to leaf node list if no other 3325d4f98a2SYan Zheng * child block cached. 3335d4f98a2SYan Zheng */ 3345d4f98a2SYan Zheng if (list_empty(&upper->lower)) { 3353fd0a558SYan, Zheng list_add_tail(&upper->lower, &cache->leaves); 3365d4f98a2SYan Zheng upper->lowest = 1; 3375d4f98a2SYan Zheng } 3385d4f98a2SYan Zheng } 3393fd0a558SYan, Zheng 3405d4f98a2SYan Zheng drop_backref_node(cache, node); 3415d4f98a2SYan Zheng } 3425d4f98a2SYan Zheng 343a26195a5SQu Wenruo static void update_backref_node(struct btrfs_backref_cache *cache, 344a26195a5SQu Wenruo struct btrfs_backref_node *node, u64 bytenr) 3453fd0a558SYan, Zheng { 3463fd0a558SYan, Zheng struct rb_node *rb_node; 3473fd0a558SYan, Zheng rb_erase(&node->rb_node, &cache->rb_root); 3483fd0a558SYan, Zheng node->bytenr = bytenr; 349e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, node->bytenr, &node->rb_node); 35043c04fb1SJeff Mahoney if (rb_node) 35143c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, bytenr); 3523fd0a558SYan, Zheng } 3533fd0a558SYan, Zheng 3543fd0a558SYan, Zheng /* 3553fd0a558SYan, Zheng * update backref cache after a transaction commit 3563fd0a558SYan, Zheng */ 3573fd0a558SYan, Zheng static int update_backref_cache(struct btrfs_trans_handle *trans, 358a26195a5SQu Wenruo struct btrfs_backref_cache *cache) 3593fd0a558SYan, Zheng { 360a26195a5SQu Wenruo struct btrfs_backref_node *node; 3613fd0a558SYan, Zheng int level = 0; 3623fd0a558SYan, Zheng 3633fd0a558SYan, Zheng if (cache->last_trans == 0) { 3643fd0a558SYan, Zheng cache->last_trans = trans->transid; 3653fd0a558SYan, Zheng return 0; 3663fd0a558SYan, Zheng } 3673fd0a558SYan, Zheng 3683fd0a558SYan, Zheng if (cache->last_trans == trans->transid) 3693fd0a558SYan, Zheng return 0; 3703fd0a558SYan, Zheng 3713fd0a558SYan, Zheng /* 3723fd0a558SYan, Zheng * detached nodes are used to avoid unnecessary backref 3733fd0a558SYan, Zheng * lookup. transaction commit changes the extent tree. 3743fd0a558SYan, Zheng * so the detached nodes are no longer useful. 3753fd0a558SYan, Zheng */ 3763fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 3773fd0a558SYan, Zheng node = list_entry(cache->detached.next, 378a26195a5SQu Wenruo struct btrfs_backref_node, list); 3793fd0a558SYan, Zheng remove_backref_node(cache, node); 3803fd0a558SYan, Zheng } 3813fd0a558SYan, Zheng 3823fd0a558SYan, Zheng while (!list_empty(&cache->changed)) { 3833fd0a558SYan, Zheng node = list_entry(cache->changed.next, 384a26195a5SQu Wenruo struct btrfs_backref_node, list); 3853fd0a558SYan, Zheng list_del_init(&node->list); 3863fd0a558SYan, Zheng BUG_ON(node->pending); 3873fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 3883fd0a558SYan, Zheng } 3893fd0a558SYan, Zheng 3903fd0a558SYan, Zheng /* 3913fd0a558SYan, Zheng * some nodes can be left in the pending list if there were 3923fd0a558SYan, Zheng * errors during processing the pending nodes. 3933fd0a558SYan, Zheng */ 3943fd0a558SYan, Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 3953fd0a558SYan, Zheng list_for_each_entry(node, &cache->pending[level], list) { 3963fd0a558SYan, Zheng BUG_ON(!node->pending); 3973fd0a558SYan, Zheng if (node->bytenr == node->new_bytenr) 3983fd0a558SYan, Zheng continue; 3993fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 4003fd0a558SYan, Zheng } 4013fd0a558SYan, Zheng } 4023fd0a558SYan, Zheng 4033fd0a558SYan, Zheng cache->last_trans = 0; 4043fd0a558SYan, Zheng return 1; 4053fd0a558SYan, Zheng } 4063fd0a558SYan, Zheng 4076282675eSQu Wenruo static bool reloc_root_is_dead(struct btrfs_root *root) 4086282675eSQu Wenruo { 4096282675eSQu Wenruo /* 4106282675eSQu Wenruo * Pair with set_bit/clear_bit in clean_dirty_subvols and 4116282675eSQu Wenruo * btrfs_update_reloc_root. We need to see the updated bit before 4126282675eSQu Wenruo * trying to access reloc_root 4136282675eSQu Wenruo */ 4146282675eSQu Wenruo smp_rmb(); 4156282675eSQu Wenruo if (test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state)) 4166282675eSQu Wenruo return true; 4176282675eSQu Wenruo return false; 4186282675eSQu Wenruo } 4196282675eSQu Wenruo 4206282675eSQu Wenruo /* 4216282675eSQu Wenruo * Check if this subvolume tree has valid reloc tree. 4226282675eSQu Wenruo * 4236282675eSQu Wenruo * Reloc tree after swap is considered dead, thus not considered as valid. 4246282675eSQu Wenruo * This is enough for most callers, as they don't distinguish dead reloc root 4256282675eSQu Wenruo * from no reloc root. But should_ignore_root() below is a special case. 4266282675eSQu Wenruo */ 4276282675eSQu Wenruo static bool have_reloc_root(struct btrfs_root *root) 4286282675eSQu Wenruo { 4296282675eSQu Wenruo if (reloc_root_is_dead(root)) 4306282675eSQu Wenruo return false; 4316282675eSQu Wenruo if (!root->reloc_root) 4326282675eSQu Wenruo return false; 4336282675eSQu Wenruo return true; 4346282675eSQu Wenruo } 435f2a97a9dSDavid Sterba 4363fd0a558SYan, Zheng static int should_ignore_root(struct btrfs_root *root) 4373fd0a558SYan, Zheng { 4383fd0a558SYan, Zheng struct btrfs_root *reloc_root; 4393fd0a558SYan, Zheng 44027cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 4413fd0a558SYan, Zheng return 0; 4423fd0a558SYan, Zheng 4436282675eSQu Wenruo /* This root has been merged with its reloc tree, we can ignore it */ 4446282675eSQu Wenruo if (reloc_root_is_dead(root)) 4456282675eSQu Wenruo return 1; 4466282675eSQu Wenruo 4473fd0a558SYan, Zheng reloc_root = root->reloc_root; 4483fd0a558SYan, Zheng if (!reloc_root) 4493fd0a558SYan, Zheng return 0; 4503fd0a558SYan, Zheng 4514d4225fcSJosef Bacik if (btrfs_header_generation(reloc_root->commit_root) == 4524d4225fcSJosef Bacik root->fs_info->running_transaction->transid) 4533fd0a558SYan, Zheng return 0; 4543fd0a558SYan, Zheng /* 4553fd0a558SYan, Zheng * if there is reloc tree and it was created in previous 4563fd0a558SYan, Zheng * transaction backref lookup can find the reloc tree, 4573fd0a558SYan, Zheng * so backref node for the fs tree root is useless for 4583fd0a558SYan, Zheng * relocation. 4593fd0a558SYan, Zheng */ 4603fd0a558SYan, Zheng return 1; 4613fd0a558SYan, Zheng } 4625d4f98a2SYan Zheng /* 4635d4f98a2SYan Zheng * find reloc tree by address of tree root 4645d4f98a2SYan Zheng */ 4652433bea5SQu Wenruo struct btrfs_root *find_reloc_root(struct btrfs_fs_info *fs_info, u64 bytenr) 4665d4f98a2SYan Zheng { 4672433bea5SQu Wenruo struct reloc_control *rc = fs_info->reloc_ctl; 4685d4f98a2SYan Zheng struct rb_node *rb_node; 4695d4f98a2SYan Zheng struct mapping_node *node; 4705d4f98a2SYan Zheng struct btrfs_root *root = NULL; 4715d4f98a2SYan Zheng 4722433bea5SQu Wenruo ASSERT(rc); 4735d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 474e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, bytenr); 4755d4f98a2SYan Zheng if (rb_node) { 4765d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 4775d4f98a2SYan Zheng root = (struct btrfs_root *)node->data; 4785d4f98a2SYan Zheng } 4795d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 48000246528SJosef Bacik return btrfs_grab_root(root); 4815d4f98a2SYan Zheng } 4825d4f98a2SYan Zheng 4835d4f98a2SYan Zheng static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, 4845d4f98a2SYan Zheng u64 root_objectid) 4855d4f98a2SYan Zheng { 4865d4f98a2SYan Zheng struct btrfs_key key; 4875d4f98a2SYan Zheng 4885d4f98a2SYan Zheng key.objectid = root_objectid; 4895d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 4905d4f98a2SYan Zheng key.offset = (u64)-1; 4915d4f98a2SYan Zheng 492bc44d7c4SJosef Bacik return btrfs_get_fs_root(fs_info, &key, false); 4935d4f98a2SYan Zheng } 4945d4f98a2SYan Zheng 4955d4f98a2SYan Zheng /* 4964007ea87SQu Wenruo * Handle direct tree backref 4974007ea87SQu Wenruo * 4984007ea87SQu Wenruo * Direct tree backref means, the backref item shows its parent bytenr 4994007ea87SQu Wenruo * directly. This is for SHARED_BLOCK_REF backref (keyed or inlined). 5004007ea87SQu Wenruo * 5014007ea87SQu Wenruo * @ref_key: The converted backref key. 5024007ea87SQu Wenruo * For keyed backref, it's the item key. 5034007ea87SQu Wenruo * For inlined backref, objectid is the bytenr, 5044007ea87SQu Wenruo * type is btrfs_inline_ref_type, offset is 5054007ea87SQu Wenruo * btrfs_inline_ref_offset. 5064007ea87SQu Wenruo */ 507a26195a5SQu Wenruo static int handle_direct_tree_backref(struct btrfs_backref_cache *cache, 5084007ea87SQu Wenruo struct btrfs_key *ref_key, 509a26195a5SQu Wenruo struct btrfs_backref_node *cur) 5104007ea87SQu Wenruo { 511a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 512a26195a5SQu Wenruo struct btrfs_backref_node *upper; 5134007ea87SQu Wenruo struct rb_node *rb_node; 5144007ea87SQu Wenruo 5154007ea87SQu Wenruo ASSERT(ref_key->type == BTRFS_SHARED_BLOCK_REF_KEY); 5164007ea87SQu Wenruo 5174007ea87SQu Wenruo /* Only reloc root uses backref pointing to itself */ 5184007ea87SQu Wenruo if (ref_key->objectid == ref_key->offset) { 5194007ea87SQu Wenruo struct btrfs_root *root; 5204007ea87SQu Wenruo 5214007ea87SQu Wenruo cur->is_reloc_root = 1; 5224007ea87SQu Wenruo /* Only reloc backref cache cares about a specific root */ 5234007ea87SQu Wenruo if (cache->is_reloc) { 5244007ea87SQu Wenruo root = find_reloc_root(cache->fs_info, cur->bytenr); 5254007ea87SQu Wenruo if (WARN_ON(!root)) 5264007ea87SQu Wenruo return -ENOENT; 5274007ea87SQu Wenruo cur->root = root; 5284007ea87SQu Wenruo } else { 5294007ea87SQu Wenruo /* 5304007ea87SQu Wenruo * For generic purpose backref cache, reloc root node 5314007ea87SQu Wenruo * is useless. 5324007ea87SQu Wenruo */ 5334007ea87SQu Wenruo list_add(&cur->list, &cache->useless_node); 5344007ea87SQu Wenruo } 5354007ea87SQu Wenruo return 0; 5364007ea87SQu Wenruo } 5374007ea87SQu Wenruo 53847254d07SQu Wenruo edge = btrfs_backref_alloc_edge(cache); 5394007ea87SQu Wenruo if (!edge) 5404007ea87SQu Wenruo return -ENOMEM; 5414007ea87SQu Wenruo 542e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, ref_key->offset); 5434007ea87SQu Wenruo if (!rb_node) { 5444007ea87SQu Wenruo /* Parent node not yet cached */ 545b1818dabSQu Wenruo upper = btrfs_backref_alloc_node(cache, ref_key->offset, 5460304f2d8SQu Wenruo cur->level + 1); 5474007ea87SQu Wenruo if (!upper) { 548741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 5494007ea87SQu Wenruo return -ENOMEM; 5504007ea87SQu Wenruo } 5514007ea87SQu Wenruo 5524007ea87SQu Wenruo /* 5534007ea87SQu Wenruo * Backrefs for the upper level block isn't cached, add the 5544007ea87SQu Wenruo * block to pending list 5554007ea87SQu Wenruo */ 5564007ea87SQu Wenruo list_add_tail(&edge->list[UPPER], &cache->pending_edge); 5574007ea87SQu Wenruo } else { 5584007ea87SQu Wenruo /* Parent node already cached */ 559a26195a5SQu Wenruo upper = rb_entry(rb_node, struct btrfs_backref_node, rb_node); 5604007ea87SQu Wenruo ASSERT(upper->checked); 5614007ea87SQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 5624007ea87SQu Wenruo } 563f39911e5SQu Wenruo btrfs_backref_link_edge(edge, cur, upper, LINK_LOWER); 5644007ea87SQu Wenruo return 0; 5654007ea87SQu Wenruo } 5664007ea87SQu Wenruo 5674007ea87SQu Wenruo /* 5684d81ea8bSQu Wenruo * Handle indirect tree backref 5694d81ea8bSQu Wenruo * 5704d81ea8bSQu Wenruo * Indirect tree backref means, we only know which tree the node belongs to. 5714d81ea8bSQu Wenruo * We still need to do a tree search to find out the parents. This is for 5724d81ea8bSQu Wenruo * TREE_BLOCK_REF backref (keyed or inlined). 5734d81ea8bSQu Wenruo * 5744d81ea8bSQu Wenruo * @ref_key: The same as @ref_key in handle_direct_tree_backref() 5754d81ea8bSQu Wenruo * @tree_key: The first key of this tree block. 5764d81ea8bSQu Wenruo * @path: A clean (released) path, to avoid allocating path everytime 5774d81ea8bSQu Wenruo * the function get called. 5784d81ea8bSQu Wenruo */ 579a26195a5SQu Wenruo static int handle_indirect_tree_backref(struct btrfs_backref_cache *cache, 5804d81ea8bSQu Wenruo struct btrfs_path *path, 5814d81ea8bSQu Wenruo struct btrfs_key *ref_key, 5824d81ea8bSQu Wenruo struct btrfs_key *tree_key, 583a26195a5SQu Wenruo struct btrfs_backref_node *cur) 5844d81ea8bSQu Wenruo { 5854d81ea8bSQu Wenruo struct btrfs_fs_info *fs_info = cache->fs_info; 586a26195a5SQu Wenruo struct btrfs_backref_node *upper; 587a26195a5SQu Wenruo struct btrfs_backref_node *lower; 588a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 5894d81ea8bSQu Wenruo struct extent_buffer *eb; 5904d81ea8bSQu Wenruo struct btrfs_root *root; 5914d81ea8bSQu Wenruo struct rb_node *rb_node; 5924d81ea8bSQu Wenruo int level; 5934d81ea8bSQu Wenruo bool need_check = true; 5944d81ea8bSQu Wenruo int ret; 5954d81ea8bSQu Wenruo 5964d81ea8bSQu Wenruo root = read_fs_root(fs_info, ref_key->offset); 5974d81ea8bSQu Wenruo if (IS_ERR(root)) 5984d81ea8bSQu Wenruo return PTR_ERR(root); 5994d81ea8bSQu Wenruo if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 6004d81ea8bSQu Wenruo cur->cowonly = 1; 6014d81ea8bSQu Wenruo 6024d81ea8bSQu Wenruo if (btrfs_root_level(&root->root_item) == cur->level) { 6034d81ea8bSQu Wenruo /* Tree root */ 6044d81ea8bSQu Wenruo ASSERT(btrfs_root_bytenr(&root->root_item) == cur->bytenr); 6054d81ea8bSQu Wenruo if (should_ignore_root(root)) { 6064d81ea8bSQu Wenruo btrfs_put_root(root); 6074d81ea8bSQu Wenruo list_add(&cur->list, &cache->useless_node); 6084d81ea8bSQu Wenruo } else { 6094d81ea8bSQu Wenruo cur->root = root; 6104d81ea8bSQu Wenruo } 6114d81ea8bSQu Wenruo return 0; 6124d81ea8bSQu Wenruo } 6134d81ea8bSQu Wenruo 6144d81ea8bSQu Wenruo level = cur->level + 1; 6154d81ea8bSQu Wenruo 6164d81ea8bSQu Wenruo /* Search the tree to find parent blocks referring to the block */ 6174d81ea8bSQu Wenruo path->search_commit_root = 1; 6184d81ea8bSQu Wenruo path->skip_locking = 1; 6194d81ea8bSQu Wenruo path->lowest_level = level; 6204d81ea8bSQu Wenruo ret = btrfs_search_slot(NULL, root, tree_key, path, 0, 0); 6214d81ea8bSQu Wenruo path->lowest_level = 0; 6224d81ea8bSQu Wenruo if (ret < 0) { 6234d81ea8bSQu Wenruo btrfs_put_root(root); 6244d81ea8bSQu Wenruo return ret; 6254d81ea8bSQu Wenruo } 6264d81ea8bSQu Wenruo if (ret > 0 && path->slots[level] > 0) 6274d81ea8bSQu Wenruo path->slots[level]--; 6284d81ea8bSQu Wenruo 6294d81ea8bSQu Wenruo eb = path->nodes[level]; 6304d81ea8bSQu Wenruo if (btrfs_node_blockptr(eb, path->slots[level]) != cur->bytenr) { 6314d81ea8bSQu Wenruo btrfs_err(fs_info, 6324d81ea8bSQu Wenruo "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)", 6334d81ea8bSQu Wenruo cur->bytenr, level - 1, root->root_key.objectid, 6344d81ea8bSQu Wenruo tree_key->objectid, tree_key->type, tree_key->offset); 6354d81ea8bSQu Wenruo btrfs_put_root(root); 6364d81ea8bSQu Wenruo ret = -ENOENT; 6374d81ea8bSQu Wenruo goto out; 6384d81ea8bSQu Wenruo } 6394d81ea8bSQu Wenruo lower = cur; 6404d81ea8bSQu Wenruo 6414d81ea8bSQu Wenruo /* Add all nodes and edges in the path */ 6424d81ea8bSQu Wenruo for (; level < BTRFS_MAX_LEVEL; level++) { 6434d81ea8bSQu Wenruo if (!path->nodes[level]) { 6444d81ea8bSQu Wenruo ASSERT(btrfs_root_bytenr(&root->root_item) == 6454d81ea8bSQu Wenruo lower->bytenr); 6464d81ea8bSQu Wenruo if (should_ignore_root(root)) { 6474d81ea8bSQu Wenruo btrfs_put_root(root); 6484d81ea8bSQu Wenruo list_add(&lower->list, &cache->useless_node); 6494d81ea8bSQu Wenruo } else { 6504d81ea8bSQu Wenruo lower->root = root; 6514d81ea8bSQu Wenruo } 6524d81ea8bSQu Wenruo break; 6534d81ea8bSQu Wenruo } 6544d81ea8bSQu Wenruo 65547254d07SQu Wenruo edge = btrfs_backref_alloc_edge(cache); 6564d81ea8bSQu Wenruo if (!edge) { 6574d81ea8bSQu Wenruo btrfs_put_root(root); 6584d81ea8bSQu Wenruo ret = -ENOMEM; 6594d81ea8bSQu Wenruo goto out; 6604d81ea8bSQu Wenruo } 6614d81ea8bSQu Wenruo 6624d81ea8bSQu Wenruo eb = path->nodes[level]; 663e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, eb->start); 6644d81ea8bSQu Wenruo if (!rb_node) { 665b1818dabSQu Wenruo upper = btrfs_backref_alloc_node(cache, eb->start, 6660304f2d8SQu Wenruo lower->level + 1); 6674d81ea8bSQu Wenruo if (!upper) { 6684d81ea8bSQu Wenruo btrfs_put_root(root); 669741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 6704d81ea8bSQu Wenruo ret = -ENOMEM; 6714d81ea8bSQu Wenruo goto out; 6724d81ea8bSQu Wenruo } 6734d81ea8bSQu Wenruo upper->owner = btrfs_header_owner(eb); 6744d81ea8bSQu Wenruo if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 6754d81ea8bSQu Wenruo upper->cowonly = 1; 6764d81ea8bSQu Wenruo 6774d81ea8bSQu Wenruo /* 6784d81ea8bSQu Wenruo * If we know the block isn't shared we can avoid 6794d81ea8bSQu Wenruo * checking its backrefs. 6804d81ea8bSQu Wenruo */ 6814d81ea8bSQu Wenruo if (btrfs_block_can_be_shared(root, eb)) 6824d81ea8bSQu Wenruo upper->checked = 0; 6834d81ea8bSQu Wenruo else 6844d81ea8bSQu Wenruo upper->checked = 1; 6854d81ea8bSQu Wenruo 6864d81ea8bSQu Wenruo /* 6874d81ea8bSQu Wenruo * Add the block to pending list if we need to check its 6884d81ea8bSQu Wenruo * backrefs, we only do this once while walking up a 6894d81ea8bSQu Wenruo * tree as we will catch anything else later on. 6904d81ea8bSQu Wenruo */ 6914d81ea8bSQu Wenruo if (!upper->checked && need_check) { 6924d81ea8bSQu Wenruo need_check = false; 6934d81ea8bSQu Wenruo list_add_tail(&edge->list[UPPER], 6944d81ea8bSQu Wenruo &cache->pending_edge); 6954d81ea8bSQu Wenruo } else { 6964d81ea8bSQu Wenruo if (upper->checked) 6974d81ea8bSQu Wenruo need_check = true; 6984d81ea8bSQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 6994d81ea8bSQu Wenruo } 7004d81ea8bSQu Wenruo } else { 701a26195a5SQu Wenruo upper = rb_entry(rb_node, struct btrfs_backref_node, 702a26195a5SQu Wenruo rb_node); 7034d81ea8bSQu Wenruo ASSERT(upper->checked); 7044d81ea8bSQu Wenruo INIT_LIST_HEAD(&edge->list[UPPER]); 7054d81ea8bSQu Wenruo if (!upper->owner) 7064d81ea8bSQu Wenruo upper->owner = btrfs_header_owner(eb); 7074d81ea8bSQu Wenruo } 708f39911e5SQu Wenruo btrfs_backref_link_edge(edge, lower, upper, LINK_LOWER); 7094d81ea8bSQu Wenruo 7104d81ea8bSQu Wenruo if (rb_node) { 7114d81ea8bSQu Wenruo btrfs_put_root(root); 7124d81ea8bSQu Wenruo break; 7134d81ea8bSQu Wenruo } 7144d81ea8bSQu Wenruo lower = upper; 7154d81ea8bSQu Wenruo upper = NULL; 7164d81ea8bSQu Wenruo } 7174d81ea8bSQu Wenruo out: 7184d81ea8bSQu Wenruo btrfs_release_path(path); 7194d81ea8bSQu Wenruo return ret; 7204d81ea8bSQu Wenruo } 7214d81ea8bSQu Wenruo 722a26195a5SQu Wenruo static int handle_one_tree_block(struct btrfs_backref_cache *cache, 723e7d571c7SQu Wenruo struct btrfs_path *path, 724e7d571c7SQu Wenruo struct btrfs_backref_iter *iter, 7255d4f98a2SYan Zheng struct btrfs_key *node_key, 726a26195a5SQu Wenruo struct btrfs_backref_node *cur) 7275d4f98a2SYan Zheng { 728e7d571c7SQu Wenruo struct btrfs_fs_info *fs_info = cache->fs_info; 729a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 730a26195a5SQu Wenruo struct btrfs_backref_node *exist; 7315d4f98a2SYan Zheng int ret; 7325d4f98a2SYan Zheng 73371f572a9SQu Wenruo ret = btrfs_backref_iter_start(iter, cur->bytenr); 734e7d571c7SQu Wenruo if (ret < 0) 735e7d571c7SQu Wenruo return ret; 73671f572a9SQu Wenruo /* 73771f572a9SQu Wenruo * We skip the first btrfs_tree_block_info, as we don't use the key 73871f572a9SQu Wenruo * stored in it, but fetch it from the tree block 73971f572a9SQu Wenruo */ 74071f572a9SQu Wenruo if (btrfs_backref_has_tree_block_info(iter)) { 74171f572a9SQu Wenruo ret = btrfs_backref_iter_next(iter); 742e7d571c7SQu Wenruo if (ret < 0) 74371f572a9SQu Wenruo goto out; 74471f572a9SQu Wenruo /* No extra backref? This means the tree block is corrupted */ 74571f572a9SQu Wenruo if (ret > 0) { 746e7d571c7SQu Wenruo ret = -EUCLEAN; 74771f572a9SQu Wenruo goto out; 74871f572a9SQu Wenruo } 74971f572a9SQu Wenruo } 7505d4f98a2SYan Zheng WARN_ON(cur->checked); 7515d4f98a2SYan Zheng if (!list_empty(&cur->upper)) { 7525d4f98a2SYan Zheng /* 75370f23fd6SJustin P. Mattock * the backref was added previously when processing 7545d4f98a2SYan Zheng * backref of type BTRFS_TREE_BLOCK_REF_KEY 7555d4f98a2SYan Zheng */ 75675bfb9afSJosef Bacik ASSERT(list_is_singular(&cur->upper)); 757a26195a5SQu Wenruo edge = list_entry(cur->upper.next, struct btrfs_backref_edge, 7585d4f98a2SYan Zheng list[LOWER]); 75975bfb9afSJosef Bacik ASSERT(list_empty(&edge->list[UPPER])); 7605d4f98a2SYan Zheng exist = edge->node[UPPER]; 7615d4f98a2SYan Zheng /* 7625d4f98a2SYan Zheng * add the upper level block to pending list if we need 7635d4f98a2SYan Zheng * check its backrefs 7645d4f98a2SYan Zheng */ 7655d4f98a2SYan Zheng if (!exist->checked) 76684780289SQu Wenruo list_add_tail(&edge->list[UPPER], &cache->pending_edge); 7675d4f98a2SYan Zheng } else { 7685d4f98a2SYan Zheng exist = NULL; 7695d4f98a2SYan Zheng } 7705d4f98a2SYan Zheng 77171f572a9SQu Wenruo for (; ret == 0; ret = btrfs_backref_iter_next(iter)) { 77271f572a9SQu Wenruo struct extent_buffer *eb; 77371f572a9SQu Wenruo struct btrfs_key key; 7743de28d57SLiu Bo int type; 77571f572a9SQu Wenruo 77671f572a9SQu Wenruo cond_resched(); 77771f572a9SQu Wenruo eb = btrfs_backref_get_eb(iter); 77871f572a9SQu Wenruo 77971f572a9SQu Wenruo key.objectid = iter->bytenr; 78071f572a9SQu Wenruo if (btrfs_backref_iter_is_inline_ref(iter)) { 78171f572a9SQu Wenruo struct btrfs_extent_inline_ref *iref; 78271f572a9SQu Wenruo 78371f572a9SQu Wenruo /* update key for inline back ref */ 78471f572a9SQu Wenruo iref = (struct btrfs_extent_inline_ref *) 78571f572a9SQu Wenruo ((unsigned long)iter->cur_ptr); 7863de28d57SLiu Bo type = btrfs_get_extent_inline_ref_type(eb, iref, 7873de28d57SLiu Bo BTRFS_REF_TYPE_BLOCK); 7883de28d57SLiu Bo if (type == BTRFS_REF_TYPE_INVALID) { 789e7d571c7SQu Wenruo ret = -EUCLEAN; 7903de28d57SLiu Bo goto out; 7913de28d57SLiu Bo } 7923de28d57SLiu Bo key.type = type; 7935d4f98a2SYan Zheng key.offset = btrfs_extent_inline_ref_offset(eb, iref); 79471f572a9SQu Wenruo } else { 79571f572a9SQu Wenruo key.type = iter->cur_key.type; 79671f572a9SQu Wenruo key.offset = iter->cur_key.offset; 7975d4f98a2SYan Zheng } 7985d4f98a2SYan Zheng 799fa6ac715SQu Wenruo /* 800fa6ac715SQu Wenruo * Parent node found and matches current inline ref, no need to 801fa6ac715SQu Wenruo * rebuild this node for this inline ref. 802fa6ac715SQu Wenruo */ 8035d4f98a2SYan Zheng if (exist && 8045d4f98a2SYan Zheng ((key.type == BTRFS_TREE_BLOCK_REF_KEY && 8055d4f98a2SYan Zheng exist->owner == key.offset) || 8065d4f98a2SYan Zheng (key.type == BTRFS_SHARED_BLOCK_REF_KEY && 8075d4f98a2SYan Zheng exist->bytenr == key.offset))) { 8085d4f98a2SYan Zheng exist = NULL; 80971f572a9SQu Wenruo continue; 8105d4f98a2SYan Zheng } 8115d4f98a2SYan Zheng 812fa6ac715SQu Wenruo /* SHARED_BLOCK_REF means key.offset is the parent bytenr */ 8135d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { 8144007ea87SQu Wenruo ret = handle_direct_tree_backref(cache, &key, cur); 815e7d571c7SQu Wenruo if (ret < 0) 8162433bea5SQu Wenruo goto out; 81771f572a9SQu Wenruo continue; 8186d8ff4e4SDavid Sterba } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) { 819e7d571c7SQu Wenruo ret = -EINVAL; 820e7d571c7SQu Wenruo btrfs_print_v0_err(fs_info); 821e7d571c7SQu Wenruo btrfs_handle_fs_error(fs_info, ret, NULL); 822ba3c2b19SNikolay Borisov goto out; 8235d4f98a2SYan Zheng } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { 82471f572a9SQu Wenruo continue; 8255d4f98a2SYan Zheng } 8265d4f98a2SYan Zheng 827fa6ac715SQu Wenruo /* 828fa6ac715SQu Wenruo * key.type == BTRFS_TREE_BLOCK_REF_KEY, inline ref offset 829fa6ac715SQu Wenruo * means the root objectid. We need to search the tree to get 830fa6ac715SQu Wenruo * its parent bytenr. 831fa6ac715SQu Wenruo */ 8324d81ea8bSQu Wenruo ret = handle_indirect_tree_backref(cache, path, &key, node_key, 8334d81ea8bSQu Wenruo cur); 834e7d571c7SQu Wenruo if (ret < 0) 83571f572a9SQu Wenruo goto out; 8365d4f98a2SYan Zheng } 83771f572a9SQu Wenruo ret = 0; 8385d4f98a2SYan Zheng cur->checked = 1; 8395d4f98a2SYan Zheng WARN_ON(exist); 840e7d571c7SQu Wenruo out: 841e7d571c7SQu Wenruo btrfs_backref_iter_release(iter); 842e7d571c7SQu Wenruo return ret; 843e7d571c7SQu Wenruo } 8445d4f98a2SYan Zheng 845e7d571c7SQu Wenruo /* 8461f872924SQu Wenruo * In handle_one_tree_backref(), we have only linked the lower node to the edge, 8471f872924SQu Wenruo * but the upper node hasn't been linked to the edge. 848a26195a5SQu Wenruo * This means we can only iterate through btrfs_backref_node::upper to reach 849a26195a5SQu Wenruo * parent edges, but not through btrfs_backref_node::lower to reach children 850a26195a5SQu Wenruo * edges. 8511f872924SQu Wenruo * 852a26195a5SQu Wenruo * This function will finish the btrfs_backref_node::lower to related edges, 853a26195a5SQu Wenruo * so that backref cache can be bi-directionally iterated. 8541f872924SQu Wenruo * 8551f872924SQu Wenruo * Also, this will add the nodes to backref cache for the next run. 8561f872924SQu Wenruo */ 857a26195a5SQu Wenruo static int finish_upper_links(struct btrfs_backref_cache *cache, 858a26195a5SQu Wenruo struct btrfs_backref_node *start) 8591f872924SQu Wenruo { 8601f872924SQu Wenruo struct list_head *useless_node = &cache->useless_node; 861a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 8621f872924SQu Wenruo struct rb_node *rb_node; 8631f872924SQu Wenruo LIST_HEAD(pending_edge); 8641f872924SQu Wenruo 8651f872924SQu Wenruo ASSERT(start->checked); 8661f872924SQu Wenruo 8671f872924SQu Wenruo /* Insert this node to cache if it's not COW-only */ 8681f872924SQu Wenruo if (!start->cowonly) { 869e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, start->bytenr, 8701f872924SQu Wenruo &start->rb_node); 8711f872924SQu Wenruo if (rb_node) 8721f872924SQu Wenruo backref_tree_panic(rb_node, -EEXIST, start->bytenr); 8731f872924SQu Wenruo list_add_tail(&start->lower, &cache->leaves); 8741f872924SQu Wenruo } 8751f872924SQu Wenruo 8761f872924SQu Wenruo /* 8771f872924SQu Wenruo * Use breadth first search to iterate all related edges. 8781f872924SQu Wenruo * 8791f872924SQu Wenruo * The starting points are all the edges of this node 8801f872924SQu Wenruo */ 8811f872924SQu Wenruo list_for_each_entry(edge, &start->upper, list[LOWER]) 8821f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &pending_edge); 8831f872924SQu Wenruo 8841f872924SQu Wenruo while (!list_empty(&pending_edge)) { 885a26195a5SQu Wenruo struct btrfs_backref_node *upper; 886a26195a5SQu Wenruo struct btrfs_backref_node *lower; 8871f872924SQu Wenruo struct rb_node *rb_node; 8881f872924SQu Wenruo 889a26195a5SQu Wenruo edge = list_first_entry(&pending_edge, 890a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 8911f872924SQu Wenruo list_del_init(&edge->list[UPPER]); 8921f872924SQu Wenruo upper = edge->node[UPPER]; 8931f872924SQu Wenruo lower = edge->node[LOWER]; 8941f872924SQu Wenruo 8951f872924SQu Wenruo /* Parent is detached, no need to keep any edges */ 8961f872924SQu Wenruo if (upper->detached) { 8971f872924SQu Wenruo list_del(&edge->list[LOWER]); 898741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 8991f872924SQu Wenruo 9001f872924SQu Wenruo /* Lower node is orphan, queue for cleanup */ 9011f872924SQu Wenruo if (list_empty(&lower->upper)) 9021f872924SQu Wenruo list_add(&lower->list, useless_node); 9031f872924SQu Wenruo continue; 9041f872924SQu Wenruo } 9051f872924SQu Wenruo 9061f872924SQu Wenruo /* 9071f872924SQu Wenruo * All new nodes added in current build_backref_tree() haven't 9081f872924SQu Wenruo * been linked to the cache rb tree. 9091f872924SQu Wenruo * So if we have upper->rb_node populated, this means a cache 9101f872924SQu Wenruo * hit. We only need to link the edge, as @upper and all its 9111f872924SQu Wenruo * parent have already been linked. 9121f872924SQu Wenruo */ 9131f872924SQu Wenruo if (!RB_EMPTY_NODE(&upper->rb_node)) { 9141f872924SQu Wenruo if (upper->lowest) { 9151f872924SQu Wenruo list_del_init(&upper->lower); 9161f872924SQu Wenruo upper->lowest = 0; 9171f872924SQu Wenruo } 9181f872924SQu Wenruo 9191f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &upper->lower); 9201f872924SQu Wenruo continue; 9211f872924SQu Wenruo } 9221f872924SQu Wenruo 9231f872924SQu Wenruo /* Sanity check, we shouldn't have any unchecked nodes */ 9241f872924SQu Wenruo if (!upper->checked) { 9251f872924SQu Wenruo ASSERT(0); 9261f872924SQu Wenruo return -EUCLEAN; 9271f872924SQu Wenruo } 9281f872924SQu Wenruo 9291f872924SQu Wenruo /* Sanity check, COW-only node has non-COW-only parent */ 9301f872924SQu Wenruo if (start->cowonly != upper->cowonly) { 9311f872924SQu Wenruo ASSERT(0); 9321f872924SQu Wenruo return -EUCLEAN; 9331f872924SQu Wenruo } 9341f872924SQu Wenruo 9351f872924SQu Wenruo /* Only cache non-COW-only (subvolume trees) tree blocks */ 9361f872924SQu Wenruo if (!upper->cowonly) { 937e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, upper->bytenr, 9381f872924SQu Wenruo &upper->rb_node); 9391f872924SQu Wenruo if (rb_node) { 9401f872924SQu Wenruo backref_tree_panic(rb_node, -EEXIST, 9411f872924SQu Wenruo upper->bytenr); 9421f872924SQu Wenruo return -EUCLEAN; 9431f872924SQu Wenruo } 9441f872924SQu Wenruo } 9451f872924SQu Wenruo 9461f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &upper->lower); 9471f872924SQu Wenruo 9481f872924SQu Wenruo /* 9491f872924SQu Wenruo * Also queue all the parent edges of this uncached node to 9501f872924SQu Wenruo * finish the upper linkage 9511f872924SQu Wenruo */ 9521f872924SQu Wenruo list_for_each_entry(edge, &upper->upper, list[LOWER]) 9531f872924SQu Wenruo list_add_tail(&edge->list[UPPER], &pending_edge); 9541f872924SQu Wenruo } 9551f872924SQu Wenruo return 0; 9561f872924SQu Wenruo } 9571f872924SQu Wenruo 9581f872924SQu Wenruo /* 95929db137bSQu Wenruo * For useless nodes, do two major clean ups: 96029db137bSQu Wenruo * 96129db137bSQu Wenruo * - Cleanup the children edges and nodes 96229db137bSQu Wenruo * If child node is also orphan (no parent) during cleanup, then the child 96329db137bSQu Wenruo * node will also be cleaned up. 96429db137bSQu Wenruo * 96529db137bSQu Wenruo * - Freeing up leaves (level 0), keeps nodes detached 96629db137bSQu Wenruo * For nodes, the node is still cached as "detached" 96729db137bSQu Wenruo * 96829db137bSQu Wenruo * Return false if @node is not in the @useless_nodes list. 96929db137bSQu Wenruo * Return true if @node is in the @useless_nodes list. 97029db137bSQu Wenruo */ 97129db137bSQu Wenruo static bool handle_useless_nodes(struct reloc_control *rc, 972a26195a5SQu Wenruo struct btrfs_backref_node *node) 97329db137bSQu Wenruo { 974a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 97529db137bSQu Wenruo struct list_head *useless_node = &cache->useless_node; 97629db137bSQu Wenruo bool ret = false; 97729db137bSQu Wenruo 97829db137bSQu Wenruo while (!list_empty(useless_node)) { 979a26195a5SQu Wenruo struct btrfs_backref_node *cur; 98029db137bSQu Wenruo 981a26195a5SQu Wenruo cur = list_first_entry(useless_node, struct btrfs_backref_node, 98229db137bSQu Wenruo list); 98329db137bSQu Wenruo list_del_init(&cur->list); 98429db137bSQu Wenruo 98529db137bSQu Wenruo /* Only tree root nodes can be added to @useless_nodes */ 98629db137bSQu Wenruo ASSERT(list_empty(&cur->upper)); 98729db137bSQu Wenruo 98829db137bSQu Wenruo if (cur == node) 98929db137bSQu Wenruo ret = true; 99029db137bSQu Wenruo 99129db137bSQu Wenruo /* The node is the lowest node */ 99229db137bSQu Wenruo if (cur->lowest) { 99329db137bSQu Wenruo list_del_init(&cur->lower); 99429db137bSQu Wenruo cur->lowest = 0; 99529db137bSQu Wenruo } 99629db137bSQu Wenruo 99729db137bSQu Wenruo /* Cleanup the lower edges */ 99829db137bSQu Wenruo while (!list_empty(&cur->lower)) { 999a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 1000a26195a5SQu Wenruo struct btrfs_backref_node *lower; 100129db137bSQu Wenruo 100229db137bSQu Wenruo edge = list_entry(cur->lower.next, 1003a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 100429db137bSQu Wenruo list_del(&edge->list[UPPER]); 100529db137bSQu Wenruo list_del(&edge->list[LOWER]); 100629db137bSQu Wenruo lower = edge->node[LOWER]; 1007741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 100829db137bSQu Wenruo 100929db137bSQu Wenruo /* Child node is also orphan, queue for cleanup */ 101029db137bSQu Wenruo if (list_empty(&lower->upper)) 101129db137bSQu Wenruo list_add(&lower->list, useless_node); 101229db137bSQu Wenruo } 101329db137bSQu Wenruo /* Mark this block processed for relocation */ 101429db137bSQu Wenruo mark_block_processed(rc, cur); 101529db137bSQu Wenruo 101629db137bSQu Wenruo /* 101729db137bSQu Wenruo * Backref nodes for tree leaves are deleted from the cache. 101829db137bSQu Wenruo * Backref nodes for upper level tree blocks are left in the 101929db137bSQu Wenruo * cache to avoid unnecessary backref lookup. 102029db137bSQu Wenruo */ 102129db137bSQu Wenruo if (cur->level > 0) { 102229db137bSQu Wenruo list_add(&cur->list, &cache->detached); 102329db137bSQu Wenruo cur->detached = 1; 102429db137bSQu Wenruo } else { 102529db137bSQu Wenruo rb_erase(&cur->rb_node, &cache->rb_root); 1026741188d3SQu Wenruo btrfs_backref_free_node(cache, cur); 102729db137bSQu Wenruo } 102829db137bSQu Wenruo } 102929db137bSQu Wenruo return ret; 103029db137bSQu Wenruo } 103129db137bSQu Wenruo 103229db137bSQu Wenruo /* 1033e7d571c7SQu Wenruo * Build backref tree for a given tree block. Root of the backref tree 1034e7d571c7SQu Wenruo * corresponds the tree block, leaves of the backref tree correspond roots of 1035e7d571c7SQu Wenruo * b-trees that reference the tree block. 1036e7d571c7SQu Wenruo * 1037e7d571c7SQu Wenruo * The basic idea of this function is check backrefs of a given block to find 1038e7d571c7SQu Wenruo * upper level blocks that reference the block, and then check backrefs of 1039e7d571c7SQu Wenruo * these upper level blocks recursively. The recursion stops when tree root is 1040e7d571c7SQu Wenruo * reached or backrefs for the block is cached. 1041e7d571c7SQu Wenruo * 1042e7d571c7SQu Wenruo * NOTE: if we find that backrefs for a block are cached, we know backrefs for 1043e7d571c7SQu Wenruo * all upper level blocks that directly/indirectly reference the block are also 1044e7d571c7SQu Wenruo * cached. 1045e7d571c7SQu Wenruo */ 1046a26195a5SQu Wenruo static noinline_for_stack struct btrfs_backref_node *build_backref_tree( 1047e7d571c7SQu Wenruo struct reloc_control *rc, struct btrfs_key *node_key, 1048e7d571c7SQu Wenruo int level, u64 bytenr) 1049e7d571c7SQu Wenruo { 1050e7d571c7SQu Wenruo struct btrfs_backref_iter *iter; 1051a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 1052e7d571c7SQu Wenruo /* For searching parent of TREE_BLOCK_REF */ 1053e7d571c7SQu Wenruo struct btrfs_path *path; 1054a26195a5SQu Wenruo struct btrfs_backref_node *cur; 1055a26195a5SQu Wenruo struct btrfs_backref_node *upper; 1056a26195a5SQu Wenruo struct btrfs_backref_node *lower; 1057a26195a5SQu Wenruo struct btrfs_backref_node *node = NULL; 1058a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 1059e7d571c7SQu Wenruo int ret; 1060e7d571c7SQu Wenruo int err = 0; 1061e7d571c7SQu Wenruo 1062e7d571c7SQu Wenruo iter = btrfs_backref_iter_alloc(rc->extent_root->fs_info, GFP_NOFS); 1063e7d571c7SQu Wenruo if (!iter) 1064e7d571c7SQu Wenruo return ERR_PTR(-ENOMEM); 1065e7d571c7SQu Wenruo path = btrfs_alloc_path(); 1066e7d571c7SQu Wenruo if (!path) { 1067e7d571c7SQu Wenruo err = -ENOMEM; 1068e7d571c7SQu Wenruo goto out; 1069e7d571c7SQu Wenruo } 1070e7d571c7SQu Wenruo 1071b1818dabSQu Wenruo node = btrfs_backref_alloc_node(cache, bytenr, level); 1072e7d571c7SQu Wenruo if (!node) { 1073e7d571c7SQu Wenruo err = -ENOMEM; 1074e7d571c7SQu Wenruo goto out; 1075e7d571c7SQu Wenruo } 1076e7d571c7SQu Wenruo 1077e7d571c7SQu Wenruo node->lowest = 1; 1078e7d571c7SQu Wenruo cur = node; 1079e7d571c7SQu Wenruo 1080e7d571c7SQu Wenruo /* Breadth-first search to build backref cache */ 1081e7d571c7SQu Wenruo do { 1082e7d571c7SQu Wenruo ret = handle_one_tree_block(cache, path, iter, node_key, cur); 1083e7d571c7SQu Wenruo if (ret < 0) { 1084e7d571c7SQu Wenruo err = ret; 1085e7d571c7SQu Wenruo goto out; 1086e7d571c7SQu Wenruo } 1087e7d571c7SQu Wenruo edge = list_first_entry_or_null(&cache->pending_edge, 1088a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 1089e7d571c7SQu Wenruo /* 1090e7d571c7SQu Wenruo * The pending list isn't empty, take the first block to 1091e7d571c7SQu Wenruo * process 1092e7d571c7SQu Wenruo */ 1093e7d571c7SQu Wenruo if (edge) { 10945d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 10955d4f98a2SYan Zheng cur = edge->node[UPPER]; 10965d4f98a2SYan Zheng } 1097e7d571c7SQu Wenruo } while (edge); 10985d4f98a2SYan Zheng 10991f872924SQu Wenruo /* Finish the upper linkage of newly added edges/nodes */ 11001f872924SQu Wenruo ret = finish_upper_links(cache, node); 11011f872924SQu Wenruo if (ret < 0) { 11021f872924SQu Wenruo err = ret; 110375bfb9afSJosef Bacik goto out; 110475bfb9afSJosef Bacik } 110575bfb9afSJosef Bacik 110629db137bSQu Wenruo if (handle_useless_nodes(rc, node)) 11073fd0a558SYan, Zheng node = NULL; 11085d4f98a2SYan Zheng out: 110971f572a9SQu Wenruo btrfs_backref_iter_free(iter); 111071f572a9SQu Wenruo btrfs_free_path(path); 11115d4f98a2SYan Zheng if (err) { 111284780289SQu Wenruo while (!list_empty(&cache->useless_node)) { 111384780289SQu Wenruo lower = list_first_entry(&cache->useless_node, 1114a26195a5SQu Wenruo struct btrfs_backref_node, list); 111575bfb9afSJosef Bacik list_del_init(&lower->list); 11163fd0a558SYan, Zheng } 111784780289SQu Wenruo while (!list_empty(&cache->pending_edge)) { 111884780289SQu Wenruo edge = list_first_entry(&cache->pending_edge, 1119a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 112075bfb9afSJosef Bacik list_del(&edge->list[UPPER]); 11213fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 112275bfb9afSJosef Bacik lower = edge->node[LOWER]; 11235d4f98a2SYan Zheng upper = edge->node[UPPER]; 1124741188d3SQu Wenruo btrfs_backref_free_edge(cache, edge); 112575bfb9afSJosef Bacik 112675bfb9afSJosef Bacik /* 112775bfb9afSJosef Bacik * Lower is no longer linked to any upper backref nodes 112875bfb9afSJosef Bacik * and isn't in the cache, we can free it ourselves. 112975bfb9afSJosef Bacik */ 113075bfb9afSJosef Bacik if (list_empty(&lower->upper) && 113175bfb9afSJosef Bacik RB_EMPTY_NODE(&lower->rb_node)) 113284780289SQu Wenruo list_add(&lower->list, &cache->useless_node); 113375bfb9afSJosef Bacik 113475bfb9afSJosef Bacik if (!RB_EMPTY_NODE(&upper->rb_node)) 113575bfb9afSJosef Bacik continue; 113675bfb9afSJosef Bacik 113701327610SNicholas D Steeves /* Add this guy's upper edges to the list to process */ 113875bfb9afSJosef Bacik list_for_each_entry(edge, &upper->upper, list[LOWER]) 113984780289SQu Wenruo list_add_tail(&edge->list[UPPER], 114084780289SQu Wenruo &cache->pending_edge); 114175bfb9afSJosef Bacik if (list_empty(&upper->upper)) 114284780289SQu Wenruo list_add(&upper->list, &cache->useless_node); 114375bfb9afSJosef Bacik } 114475bfb9afSJosef Bacik 114584780289SQu Wenruo while (!list_empty(&cache->useless_node)) { 114684780289SQu Wenruo lower = list_first_entry(&cache->useless_node, 1147a26195a5SQu Wenruo struct btrfs_backref_node, list); 114875bfb9afSJosef Bacik list_del_init(&lower->list); 11490fd8c3daSLiu Bo if (lower == node) 11500fd8c3daSLiu Bo node = NULL; 1151741188d3SQu Wenruo btrfs_backref_free_node(cache, lower); 11525d4f98a2SYan Zheng } 11530fd8c3daSLiu Bo 11548e19c973SJosef Bacik remove_backref_node(cache, node); 115584780289SQu Wenruo ASSERT(list_empty(&cache->useless_node) && 115684780289SQu Wenruo list_empty(&cache->pending_edge)); 11575d4f98a2SYan Zheng return ERR_PTR(err); 11585d4f98a2SYan Zheng } 115975bfb9afSJosef Bacik ASSERT(!node || !node->detached); 116084780289SQu Wenruo ASSERT(list_empty(&cache->useless_node) && 116184780289SQu Wenruo list_empty(&cache->pending_edge)); 11625d4f98a2SYan Zheng return node; 11635d4f98a2SYan Zheng } 11645d4f98a2SYan Zheng 11655d4f98a2SYan Zheng /* 11663fd0a558SYan, Zheng * helper to add backref node for the newly created snapshot. 11673fd0a558SYan, Zheng * the backref node is created by cloning backref node that 11683fd0a558SYan, Zheng * corresponds to root of source tree 11693fd0a558SYan, Zheng */ 11703fd0a558SYan, Zheng static int clone_backref_node(struct btrfs_trans_handle *trans, 11713fd0a558SYan, Zheng struct reloc_control *rc, 11723fd0a558SYan, Zheng struct btrfs_root *src, 11733fd0a558SYan, Zheng struct btrfs_root *dest) 11743fd0a558SYan, Zheng { 11753fd0a558SYan, Zheng struct btrfs_root *reloc_root = src->reloc_root; 1176a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 1177a26195a5SQu Wenruo struct btrfs_backref_node *node = NULL; 1178a26195a5SQu Wenruo struct btrfs_backref_node *new_node; 1179a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 1180a26195a5SQu Wenruo struct btrfs_backref_edge *new_edge; 11813fd0a558SYan, Zheng struct rb_node *rb_node; 11823fd0a558SYan, Zheng 11833fd0a558SYan, Zheng if (cache->last_trans > 0) 11843fd0a558SYan, Zheng update_backref_cache(trans, cache); 11853fd0a558SYan, Zheng 1186e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, src->commit_root->start); 11873fd0a558SYan, Zheng if (rb_node) { 1188a26195a5SQu Wenruo node = rb_entry(rb_node, struct btrfs_backref_node, rb_node); 11893fd0a558SYan, Zheng if (node->detached) 11903fd0a558SYan, Zheng node = NULL; 11913fd0a558SYan, Zheng else 11923fd0a558SYan, Zheng BUG_ON(node->new_bytenr != reloc_root->node->start); 11933fd0a558SYan, Zheng } 11943fd0a558SYan, Zheng 11953fd0a558SYan, Zheng if (!node) { 1196e9a28dc5SQu Wenruo rb_node = rb_simple_search(&cache->rb_root, 11973fd0a558SYan, Zheng reloc_root->commit_root->start); 11983fd0a558SYan, Zheng if (rb_node) { 1199a26195a5SQu Wenruo node = rb_entry(rb_node, struct btrfs_backref_node, 12003fd0a558SYan, Zheng rb_node); 12013fd0a558SYan, Zheng BUG_ON(node->detached); 12023fd0a558SYan, Zheng } 12033fd0a558SYan, Zheng } 12043fd0a558SYan, Zheng 12053fd0a558SYan, Zheng if (!node) 12063fd0a558SYan, Zheng return 0; 12073fd0a558SYan, Zheng 1208b1818dabSQu Wenruo new_node = btrfs_backref_alloc_node(cache, dest->node->start, 1209b1818dabSQu Wenruo node->level); 12103fd0a558SYan, Zheng if (!new_node) 12113fd0a558SYan, Zheng return -ENOMEM; 12123fd0a558SYan, Zheng 12133fd0a558SYan, Zheng new_node->lowest = node->lowest; 12146848ad64SYan, Zheng new_node->checked = 1; 121500246528SJosef Bacik new_node->root = btrfs_grab_root(dest); 12160b530bc5SJosef Bacik ASSERT(new_node->root); 12173fd0a558SYan, Zheng 12183fd0a558SYan, Zheng if (!node->lowest) { 12193fd0a558SYan, Zheng list_for_each_entry(edge, &node->lower, list[UPPER]) { 122047254d07SQu Wenruo new_edge = btrfs_backref_alloc_edge(cache); 12213fd0a558SYan, Zheng if (!new_edge) 12223fd0a558SYan, Zheng goto fail; 12233fd0a558SYan, Zheng 1224f39911e5SQu Wenruo btrfs_backref_link_edge(new_edge, edge->node[LOWER], 1225f39911e5SQu Wenruo new_node, LINK_UPPER); 12263fd0a558SYan, Zheng } 122776b9e23dSMiao Xie } else { 122876b9e23dSMiao Xie list_add_tail(&new_node->lower, &cache->leaves); 12293fd0a558SYan, Zheng } 12303fd0a558SYan, Zheng 1231e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&cache->rb_root, new_node->bytenr, 12323fd0a558SYan, Zheng &new_node->rb_node); 123343c04fb1SJeff Mahoney if (rb_node) 123443c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, new_node->bytenr); 12353fd0a558SYan, Zheng 12363fd0a558SYan, Zheng if (!new_node->lowest) { 12373fd0a558SYan, Zheng list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) { 12383fd0a558SYan, Zheng list_add_tail(&new_edge->list[LOWER], 12393fd0a558SYan, Zheng &new_edge->node[LOWER]->upper); 12403fd0a558SYan, Zheng } 12413fd0a558SYan, Zheng } 12423fd0a558SYan, Zheng return 0; 12433fd0a558SYan, Zheng fail: 12443fd0a558SYan, Zheng while (!list_empty(&new_node->lower)) { 12453fd0a558SYan, Zheng new_edge = list_entry(new_node->lower.next, 1246a26195a5SQu Wenruo struct btrfs_backref_edge, list[UPPER]); 12473fd0a558SYan, Zheng list_del(&new_edge->list[UPPER]); 1248741188d3SQu Wenruo btrfs_backref_free_edge(cache, new_edge); 12493fd0a558SYan, Zheng } 1250741188d3SQu Wenruo btrfs_backref_free_node(cache, new_node); 12513fd0a558SYan, Zheng return -ENOMEM; 12523fd0a558SYan, Zheng } 12533fd0a558SYan, Zheng 12543fd0a558SYan, Zheng /* 12555d4f98a2SYan Zheng * helper to add 'address of tree root -> reloc tree' mapping 12565d4f98a2SYan Zheng */ 1257ffd7b339SJeff Mahoney static int __must_check __add_reloc_root(struct btrfs_root *root) 12585d4f98a2SYan Zheng { 12590b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12605d4f98a2SYan Zheng struct rb_node *rb_node; 12615d4f98a2SYan Zheng struct mapping_node *node; 12620b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 12635d4f98a2SYan Zheng 12645d4f98a2SYan Zheng node = kmalloc(sizeof(*node), GFP_NOFS); 1265ffd7b339SJeff Mahoney if (!node) 1266ffd7b339SJeff Mahoney return -ENOMEM; 12675d4f98a2SYan Zheng 1268ea287ab1SJosef Bacik node->bytenr = root->commit_root->start; 12695d4f98a2SYan Zheng node->data = root; 12705d4f98a2SYan Zheng 12715d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1272e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&rc->reloc_root_tree.rb_root, 12735d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12745d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 1275ffd7b339SJeff Mahoney if (rb_node) { 12760b246afaSJeff Mahoney btrfs_panic(fs_info, -EEXIST, 12775d163e0eSJeff Mahoney "Duplicate root found for start=%llu while inserting into relocation tree", 12785d163e0eSJeff Mahoney node->bytenr); 1279ffd7b339SJeff Mahoney } 12805d4f98a2SYan Zheng 12815d4f98a2SYan Zheng list_add_tail(&root->root_list, &rc->reloc_roots); 12825d4f98a2SYan Zheng return 0; 12835d4f98a2SYan Zheng } 12845d4f98a2SYan Zheng 12855d4f98a2SYan Zheng /* 1286c974c464SWang Shilong * helper to delete the 'address of tree root -> reloc tree' 12875d4f98a2SYan Zheng * mapping 12885d4f98a2SYan Zheng */ 1289c974c464SWang Shilong static void __del_reloc_root(struct btrfs_root *root) 12905d4f98a2SYan Zheng { 12910b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 12925d4f98a2SYan Zheng struct rb_node *rb_node; 12935d4f98a2SYan Zheng struct mapping_node *node = NULL; 12940b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1295f44deb74SJosef Bacik bool put_ref = false; 12965d4f98a2SYan Zheng 129765c6e82bSQu Wenruo if (rc && root->node) { 12985d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1299e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, 1300ea287ab1SJosef Bacik root->commit_root->start); 1301c974c464SWang Shilong if (rb_node) { 1302c974c464SWang Shilong node = rb_entry(rb_node, struct mapping_node, rb_node); 1303c974c464SWang Shilong rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 1304ea287ab1SJosef Bacik RB_CLEAR_NODE(&node->rb_node); 1305c974c464SWang Shilong } 1306c974c464SWang Shilong spin_unlock(&rc->reloc_root_tree.lock); 1307c974c464SWang Shilong if (!node) 1308c974c464SWang Shilong return; 1309c974c464SWang Shilong BUG_ON((struct btrfs_root *)node->data != root); 1310389305b2SQu Wenruo } 1311c974c464SWang Shilong 1312f44deb74SJosef Bacik /* 1313f44deb74SJosef Bacik * We only put the reloc root here if it's on the list. There's a lot 1314f44deb74SJosef Bacik * of places where the pattern is to splice the rc->reloc_roots, process 1315f44deb74SJosef Bacik * the reloc roots, and then add the reloc root back onto 1316f44deb74SJosef Bacik * rc->reloc_roots. If we call __del_reloc_root while it's off of the 1317f44deb74SJosef Bacik * list we don't want the reference being dropped, because the guy 1318f44deb74SJosef Bacik * messing with the list is in charge of the reference. 1319f44deb74SJosef Bacik */ 13200b246afaSJeff Mahoney spin_lock(&fs_info->trans_lock); 1321f44deb74SJosef Bacik if (!list_empty(&root->root_list)) { 1322f44deb74SJosef Bacik put_ref = true; 1323c974c464SWang Shilong list_del_init(&root->root_list); 1324f44deb74SJosef Bacik } 13250b246afaSJeff Mahoney spin_unlock(&fs_info->trans_lock); 1326f44deb74SJosef Bacik if (put_ref) 1327f44deb74SJosef Bacik btrfs_put_root(root); 1328c974c464SWang Shilong kfree(node); 1329c974c464SWang Shilong } 1330c974c464SWang Shilong 1331c974c464SWang Shilong /* 1332c974c464SWang Shilong * helper to update the 'address of tree root -> reloc tree' 1333c974c464SWang Shilong * mapping 1334c974c464SWang Shilong */ 1335ea287ab1SJosef Bacik static int __update_reloc_root(struct btrfs_root *root) 1336c974c464SWang Shilong { 13370b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 1338c974c464SWang Shilong struct rb_node *rb_node; 1339c974c464SWang Shilong struct mapping_node *node = NULL; 13400b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 1341c974c464SWang Shilong 1342c974c464SWang Shilong spin_lock(&rc->reloc_root_tree.lock); 1343e9a28dc5SQu Wenruo rb_node = rb_simple_search(&rc->reloc_root_tree.rb_root, 1344ea287ab1SJosef Bacik root->commit_root->start); 13455d4f98a2SYan Zheng if (rb_node) { 13465d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 13475d4f98a2SYan Zheng rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 13485d4f98a2SYan Zheng } 13495d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 13505d4f98a2SYan Zheng 13518f71f3e0SLiu Bo if (!node) 13528f71f3e0SLiu Bo return 0; 13535d4f98a2SYan Zheng BUG_ON((struct btrfs_root *)node->data != root); 13545d4f98a2SYan Zheng 13555d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 1356ea287ab1SJosef Bacik node->bytenr = root->node->start; 1357e9a28dc5SQu Wenruo rb_node = rb_simple_insert(&rc->reloc_root_tree.rb_root, 13585d4f98a2SYan Zheng node->bytenr, &node->rb_node); 13595d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 136043c04fb1SJeff Mahoney if (rb_node) 136143c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, node->bytenr); 13625d4f98a2SYan Zheng return 0; 13635d4f98a2SYan Zheng } 13645d4f98a2SYan Zheng 13653fd0a558SYan, Zheng static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, 13663fd0a558SYan, Zheng struct btrfs_root *root, u64 objectid) 13675d4f98a2SYan Zheng { 13680b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 13695d4f98a2SYan Zheng struct btrfs_root *reloc_root; 13705d4f98a2SYan Zheng struct extent_buffer *eb; 13715d4f98a2SYan Zheng struct btrfs_root_item *root_item; 13725d4f98a2SYan Zheng struct btrfs_key root_key; 13735d4f98a2SYan Zheng int ret; 13745d4f98a2SYan Zheng 13755d4f98a2SYan Zheng root_item = kmalloc(sizeof(*root_item), GFP_NOFS); 13765d4f98a2SYan Zheng BUG_ON(!root_item); 13775d4f98a2SYan Zheng 13785d4f98a2SYan Zheng root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; 13795d4f98a2SYan Zheng root_key.type = BTRFS_ROOT_ITEM_KEY; 13803fd0a558SYan, Zheng root_key.offset = objectid; 13815d4f98a2SYan Zheng 13823fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 1383054570a1SFilipe Manana u64 commit_root_gen; 1384054570a1SFilipe Manana 13853fd0a558SYan, Zheng /* called by btrfs_init_reloc_root */ 13865d4f98a2SYan Zheng ret = btrfs_copy_root(trans, root, root->commit_root, &eb, 13875d4f98a2SYan Zheng BTRFS_TREE_RELOC_OBJECTID); 13885d4f98a2SYan Zheng BUG_ON(ret); 1389054570a1SFilipe Manana /* 1390054570a1SFilipe Manana * Set the last_snapshot field to the generation of the commit 1391054570a1SFilipe Manana * root - like this ctree.c:btrfs_block_can_be_shared() behaves 1392054570a1SFilipe Manana * correctly (returns true) when the relocation root is created 1393054570a1SFilipe Manana * either inside the critical section of a transaction commit 1394054570a1SFilipe Manana * (through transaction.c:qgroup_account_snapshot()) and when 1395054570a1SFilipe Manana * it's created before the transaction commit is started. 1396054570a1SFilipe Manana */ 1397054570a1SFilipe Manana commit_root_gen = btrfs_header_generation(root->commit_root); 1398054570a1SFilipe Manana btrfs_set_root_last_snapshot(&root->root_item, commit_root_gen); 13993fd0a558SYan, Zheng } else { 14003fd0a558SYan, Zheng /* 14013fd0a558SYan, Zheng * called by btrfs_reloc_post_snapshot_hook. 14023fd0a558SYan, Zheng * the source tree is a reloc tree, all tree blocks 14033fd0a558SYan, Zheng * modified after it was created have RELOC flag 14043fd0a558SYan, Zheng * set in their headers. so it's OK to not update 14053fd0a558SYan, Zheng * the 'last_snapshot'. 14063fd0a558SYan, Zheng */ 14073fd0a558SYan, Zheng ret = btrfs_copy_root(trans, root, root->node, &eb, 14083fd0a558SYan, Zheng BTRFS_TREE_RELOC_OBJECTID); 14093fd0a558SYan, Zheng BUG_ON(ret); 14103fd0a558SYan, Zheng } 14113fd0a558SYan, Zheng 14125d4f98a2SYan Zheng memcpy(root_item, &root->root_item, sizeof(*root_item)); 14135d4f98a2SYan Zheng btrfs_set_root_bytenr(root_item, eb->start); 14145d4f98a2SYan Zheng btrfs_set_root_level(root_item, btrfs_header_level(eb)); 14155d4f98a2SYan Zheng btrfs_set_root_generation(root_item, trans->transid); 14163fd0a558SYan, Zheng 14173fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 14183fd0a558SYan, Zheng btrfs_set_root_refs(root_item, 0); 14193fd0a558SYan, Zheng memset(&root_item->drop_progress, 0, 14203fd0a558SYan, Zheng sizeof(struct btrfs_disk_key)); 14215d4f98a2SYan Zheng root_item->drop_level = 0; 14223fd0a558SYan, Zheng } 14235d4f98a2SYan Zheng 14245d4f98a2SYan Zheng btrfs_tree_unlock(eb); 14255d4f98a2SYan Zheng free_extent_buffer(eb); 14265d4f98a2SYan Zheng 14270b246afaSJeff Mahoney ret = btrfs_insert_root(trans, fs_info->tree_root, 14285d4f98a2SYan Zheng &root_key, root_item); 14295d4f98a2SYan Zheng BUG_ON(ret); 14305d4f98a2SYan Zheng kfree(root_item); 14315d4f98a2SYan Zheng 14323dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(fs_info->tree_root, &root_key); 14335d4f98a2SYan Zheng BUG_ON(IS_ERR(reloc_root)); 14343dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 14355d4f98a2SYan Zheng reloc_root->last_trans = trans->transid; 14363fd0a558SYan, Zheng return reloc_root; 14373fd0a558SYan, Zheng } 14383fd0a558SYan, Zheng 14393fd0a558SYan, Zheng /* 14403fd0a558SYan, Zheng * create reloc tree for a given fs tree. reloc tree is just a 14413fd0a558SYan, Zheng * snapshot of the fs tree with special root objectid. 1442f44deb74SJosef Bacik * 1443f44deb74SJosef Bacik * The reloc_root comes out of here with two references, one for 1444f44deb74SJosef Bacik * root->reloc_root, and another for being on the rc->reloc_roots list. 14453fd0a558SYan, Zheng */ 14463fd0a558SYan, Zheng int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, 14473fd0a558SYan, Zheng struct btrfs_root *root) 14483fd0a558SYan, Zheng { 14490b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 14503fd0a558SYan, Zheng struct btrfs_root *reloc_root; 14510b246afaSJeff Mahoney struct reloc_control *rc = fs_info->reloc_ctl; 145220dd2cbfSMiao Xie struct btrfs_block_rsv *rsv; 14533fd0a558SYan, Zheng int clear_rsv = 0; 1454ffd7b339SJeff Mahoney int ret; 14553fd0a558SYan, Zheng 1456aec7db3bSJosef Bacik if (!rc) 14572abc726aSJosef Bacik return 0; 14582abc726aSJosef Bacik 14591fac4a54SQu Wenruo /* 14601fac4a54SQu Wenruo * The subvolume has reloc tree but the swap is finished, no need to 14611fac4a54SQu Wenruo * create/update the dead reloc tree 14621fac4a54SQu Wenruo */ 14636282675eSQu Wenruo if (reloc_root_is_dead(root)) 14641fac4a54SQu Wenruo return 0; 14651fac4a54SQu Wenruo 1466aec7db3bSJosef Bacik /* 1467aec7db3bSJosef Bacik * This is subtle but important. We do not do 1468aec7db3bSJosef Bacik * record_root_in_transaction for reloc roots, instead we record their 1469aec7db3bSJosef Bacik * corresponding fs root, and then here we update the last trans for the 1470aec7db3bSJosef Bacik * reloc root. This means that we have to do this for the entire life 1471aec7db3bSJosef Bacik * of the reloc root, regardless of which stage of the relocation we are 1472aec7db3bSJosef Bacik * in. 1473aec7db3bSJosef Bacik */ 14743fd0a558SYan, Zheng if (root->reloc_root) { 14753fd0a558SYan, Zheng reloc_root = root->reloc_root; 14763fd0a558SYan, Zheng reloc_root->last_trans = trans->transid; 14773fd0a558SYan, Zheng return 0; 14783fd0a558SYan, Zheng } 14793fd0a558SYan, Zheng 1480aec7db3bSJosef Bacik /* 1481aec7db3bSJosef Bacik * We are merging reloc roots, we do not need new reloc trees. Also 1482aec7db3bSJosef Bacik * reloc trees never need their own reloc tree. 1483aec7db3bSJosef Bacik */ 1484aec7db3bSJosef Bacik if (!rc->create_reloc_tree || 1485aec7db3bSJosef Bacik root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 1486aec7db3bSJosef Bacik return 0; 1487aec7db3bSJosef Bacik 148820dd2cbfSMiao Xie if (!trans->reloc_reserved) { 148920dd2cbfSMiao Xie rsv = trans->block_rsv; 14903fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 14913fd0a558SYan, Zheng clear_rsv = 1; 14923fd0a558SYan, Zheng } 14933fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root, root->root_key.objectid); 14943fd0a558SYan, Zheng if (clear_rsv) 149520dd2cbfSMiao Xie trans->block_rsv = rsv; 14965d4f98a2SYan Zheng 1497ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 1498ffd7b339SJeff Mahoney BUG_ON(ret < 0); 1499f44deb74SJosef Bacik root->reloc_root = btrfs_grab_root(reloc_root); 15005d4f98a2SYan Zheng return 0; 15015d4f98a2SYan Zheng } 15025d4f98a2SYan Zheng 15035d4f98a2SYan Zheng /* 15045d4f98a2SYan Zheng * update root item of reloc tree 15055d4f98a2SYan Zheng */ 15065d4f98a2SYan Zheng int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, 15075d4f98a2SYan Zheng struct btrfs_root *root) 15085d4f98a2SYan Zheng { 15090b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 15105d4f98a2SYan Zheng struct btrfs_root *reloc_root; 15115d4f98a2SYan Zheng struct btrfs_root_item *root_item; 15125d4f98a2SYan Zheng int ret; 15135d4f98a2SYan Zheng 15146282675eSQu Wenruo if (!have_reloc_root(root)) 15157585717fSChris Mason goto out; 15165d4f98a2SYan Zheng 15175d4f98a2SYan Zheng reloc_root = root->reloc_root; 15185d4f98a2SYan Zheng root_item = &reloc_root->root_item; 15195d4f98a2SYan Zheng 1520f44deb74SJosef Bacik /* 1521f44deb74SJosef Bacik * We are probably ok here, but __del_reloc_root() will drop its ref of 1522f44deb74SJosef Bacik * the root. We have the ref for root->reloc_root, but just in case 1523f44deb74SJosef Bacik * hold it while we update the reloc root. 1524f44deb74SJosef Bacik */ 1525f44deb74SJosef Bacik btrfs_grab_root(reloc_root); 1526f44deb74SJosef Bacik 1527d2311e69SQu Wenruo /* root->reloc_root will stay until current relocation finished */ 15280b246afaSJeff Mahoney if (fs_info->reloc_ctl->merge_reloc_tree && 15293fd0a558SYan, Zheng btrfs_root_refs(root_item) == 0) { 1530d2311e69SQu Wenruo set_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 15316282675eSQu Wenruo /* 15326282675eSQu Wenruo * Mark the tree as dead before we change reloc_root so 15336282675eSQu Wenruo * have_reloc_root will not touch it from now on. 15346282675eSQu Wenruo */ 15356282675eSQu Wenruo smp_wmb(); 1536c974c464SWang Shilong __del_reloc_root(reloc_root); 15375d4f98a2SYan Zheng } 15385d4f98a2SYan Zheng 15395d4f98a2SYan Zheng if (reloc_root->commit_root != reloc_root->node) { 1540ea287ab1SJosef Bacik __update_reloc_root(reloc_root); 15415d4f98a2SYan Zheng btrfs_set_root_node(root_item, reloc_root->node); 15425d4f98a2SYan Zheng free_extent_buffer(reloc_root->commit_root); 15435d4f98a2SYan Zheng reloc_root->commit_root = btrfs_root_node(reloc_root); 15445d4f98a2SYan Zheng } 15455d4f98a2SYan Zheng 15460b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 15475d4f98a2SYan Zheng &reloc_root->root_key, root_item); 15485d4f98a2SYan Zheng BUG_ON(ret); 1549f44deb74SJosef Bacik btrfs_put_root(reloc_root); 15507585717fSChris Mason out: 15515d4f98a2SYan Zheng return 0; 15525d4f98a2SYan Zheng } 15535d4f98a2SYan Zheng 15545d4f98a2SYan Zheng /* 15555d4f98a2SYan Zheng * helper to find first cached inode with inode number >= objectid 15565d4f98a2SYan Zheng * in a subvolume 15575d4f98a2SYan Zheng */ 15585d4f98a2SYan Zheng static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) 15595d4f98a2SYan Zheng { 15605d4f98a2SYan Zheng struct rb_node *node; 15615d4f98a2SYan Zheng struct rb_node *prev; 15625d4f98a2SYan Zheng struct btrfs_inode *entry; 15635d4f98a2SYan Zheng struct inode *inode; 15645d4f98a2SYan Zheng 15655d4f98a2SYan Zheng spin_lock(&root->inode_lock); 15665d4f98a2SYan Zheng again: 15675d4f98a2SYan Zheng node = root->inode_tree.rb_node; 15685d4f98a2SYan Zheng prev = NULL; 15695d4f98a2SYan Zheng while (node) { 15705d4f98a2SYan Zheng prev = node; 15715d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 15725d4f98a2SYan Zheng 15734a0cc7caSNikolay Borisov if (objectid < btrfs_ino(entry)) 15745d4f98a2SYan Zheng node = node->rb_left; 15754a0cc7caSNikolay Borisov else if (objectid > btrfs_ino(entry)) 15765d4f98a2SYan Zheng node = node->rb_right; 15775d4f98a2SYan Zheng else 15785d4f98a2SYan Zheng break; 15795d4f98a2SYan Zheng } 15805d4f98a2SYan Zheng if (!node) { 15815d4f98a2SYan Zheng while (prev) { 15825d4f98a2SYan Zheng entry = rb_entry(prev, struct btrfs_inode, rb_node); 15834a0cc7caSNikolay Borisov if (objectid <= btrfs_ino(entry)) { 15845d4f98a2SYan Zheng node = prev; 15855d4f98a2SYan Zheng break; 15865d4f98a2SYan Zheng } 15875d4f98a2SYan Zheng prev = rb_next(prev); 15885d4f98a2SYan Zheng } 15895d4f98a2SYan Zheng } 15905d4f98a2SYan Zheng while (node) { 15915d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 15925d4f98a2SYan Zheng inode = igrab(&entry->vfs_inode); 15935d4f98a2SYan Zheng if (inode) { 15945d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 15955d4f98a2SYan Zheng return inode; 15965d4f98a2SYan Zheng } 15975d4f98a2SYan Zheng 15984a0cc7caSNikolay Borisov objectid = btrfs_ino(entry) + 1; 15995d4f98a2SYan Zheng if (cond_resched_lock(&root->inode_lock)) 16005d4f98a2SYan Zheng goto again; 16015d4f98a2SYan Zheng 16025d4f98a2SYan Zheng node = rb_next(node); 16035d4f98a2SYan Zheng } 16045d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 16055d4f98a2SYan Zheng return NULL; 16065d4f98a2SYan Zheng } 16075d4f98a2SYan Zheng 16085d4f98a2SYan Zheng /* 16095d4f98a2SYan Zheng * get new location of data 16105d4f98a2SYan Zheng */ 16115d4f98a2SYan Zheng static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, 16125d4f98a2SYan Zheng u64 bytenr, u64 num_bytes) 16135d4f98a2SYan Zheng { 16145d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(reloc_inode)->root; 16155d4f98a2SYan Zheng struct btrfs_path *path; 16165d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 16175d4f98a2SYan Zheng struct extent_buffer *leaf; 16185d4f98a2SYan Zheng int ret; 16195d4f98a2SYan Zheng 16205d4f98a2SYan Zheng path = btrfs_alloc_path(); 16215d4f98a2SYan Zheng if (!path) 16225d4f98a2SYan Zheng return -ENOMEM; 16235d4f98a2SYan Zheng 16245d4f98a2SYan Zheng bytenr -= BTRFS_I(reloc_inode)->index_cnt; 1625f85b7379SDavid Sterba ret = btrfs_lookup_file_extent(NULL, root, path, 1626f85b7379SDavid Sterba btrfs_ino(BTRFS_I(reloc_inode)), bytenr, 0); 16275d4f98a2SYan Zheng if (ret < 0) 16285d4f98a2SYan Zheng goto out; 16295d4f98a2SYan Zheng if (ret > 0) { 16305d4f98a2SYan Zheng ret = -ENOENT; 16315d4f98a2SYan Zheng goto out; 16325d4f98a2SYan Zheng } 16335d4f98a2SYan Zheng 16345d4f98a2SYan Zheng leaf = path->nodes[0]; 16355d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, path->slots[0], 16365d4f98a2SYan Zheng struct btrfs_file_extent_item); 16375d4f98a2SYan Zheng 16385d4f98a2SYan Zheng BUG_ON(btrfs_file_extent_offset(leaf, fi) || 16395d4f98a2SYan Zheng btrfs_file_extent_compression(leaf, fi) || 16405d4f98a2SYan Zheng btrfs_file_extent_encryption(leaf, fi) || 16415d4f98a2SYan Zheng btrfs_file_extent_other_encoding(leaf, fi)); 16425d4f98a2SYan Zheng 16435d4f98a2SYan Zheng if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { 164483d4cfd4SJosef Bacik ret = -EINVAL; 16455d4f98a2SYan Zheng goto out; 16465d4f98a2SYan Zheng } 16475d4f98a2SYan Zheng 16485d4f98a2SYan Zheng *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 16495d4f98a2SYan Zheng ret = 0; 16505d4f98a2SYan Zheng out: 16515d4f98a2SYan Zheng btrfs_free_path(path); 16525d4f98a2SYan Zheng return ret; 16535d4f98a2SYan Zheng } 16545d4f98a2SYan Zheng 16555d4f98a2SYan Zheng /* 16565d4f98a2SYan Zheng * update file extent items in the tree leaf to point to 16575d4f98a2SYan Zheng * the new locations. 16585d4f98a2SYan Zheng */ 16593fd0a558SYan, Zheng static noinline_for_stack 16603fd0a558SYan, Zheng int replace_file_extents(struct btrfs_trans_handle *trans, 16615d4f98a2SYan Zheng struct reloc_control *rc, 16625d4f98a2SYan Zheng struct btrfs_root *root, 16633fd0a558SYan, Zheng struct extent_buffer *leaf) 16645d4f98a2SYan Zheng { 16650b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 16665d4f98a2SYan Zheng struct btrfs_key key; 16675d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 16685d4f98a2SYan Zheng struct inode *inode = NULL; 16695d4f98a2SYan Zheng u64 parent; 16705d4f98a2SYan Zheng u64 bytenr; 16713fd0a558SYan, Zheng u64 new_bytenr = 0; 16725d4f98a2SYan Zheng u64 num_bytes; 16735d4f98a2SYan Zheng u64 end; 16745d4f98a2SYan Zheng u32 nritems; 16755d4f98a2SYan Zheng u32 i; 167683d4cfd4SJosef Bacik int ret = 0; 16775d4f98a2SYan Zheng int first = 1; 16785d4f98a2SYan Zheng int dirty = 0; 16795d4f98a2SYan Zheng 16805d4f98a2SYan Zheng if (rc->stage != UPDATE_DATA_PTRS) 16815d4f98a2SYan Zheng return 0; 16825d4f98a2SYan Zheng 16835d4f98a2SYan Zheng /* reloc trees always use full backref */ 16845d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 16855d4f98a2SYan Zheng parent = leaf->start; 16865d4f98a2SYan Zheng else 16875d4f98a2SYan Zheng parent = 0; 16885d4f98a2SYan Zheng 16895d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 16905d4f98a2SYan Zheng for (i = 0; i < nritems; i++) { 169182fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 169282fa113fSQu Wenruo 16935d4f98a2SYan Zheng cond_resched(); 16945d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, i); 16955d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_DATA_KEY) 16965d4f98a2SYan Zheng continue; 16975d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 16985d4f98a2SYan Zheng if (btrfs_file_extent_type(leaf, fi) == 16995d4f98a2SYan Zheng BTRFS_FILE_EXTENT_INLINE) 17005d4f98a2SYan Zheng continue; 17015d4f98a2SYan Zheng bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 17025d4f98a2SYan Zheng num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); 17035d4f98a2SYan Zheng if (bytenr == 0) 17045d4f98a2SYan Zheng continue; 17059569cc20SQu Wenruo if (!in_range(bytenr, rc->block_group->start, 17069569cc20SQu Wenruo rc->block_group->length)) 17075d4f98a2SYan Zheng continue; 17085d4f98a2SYan Zheng 17095d4f98a2SYan Zheng /* 17105d4f98a2SYan Zheng * if we are modifying block in fs tree, wait for readpage 17115d4f98a2SYan Zheng * to complete and drop the extent cache 17125d4f98a2SYan Zheng */ 17135d4f98a2SYan Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 17145d4f98a2SYan Zheng if (first) { 17155d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 17165d4f98a2SYan Zheng first = 0; 17174a0cc7caSNikolay Borisov } else if (inode && btrfs_ino(BTRFS_I(inode)) < key.objectid) { 17183fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 17195d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 17205d4f98a2SYan Zheng } 17214a0cc7caSNikolay Borisov if (inode && btrfs_ino(BTRFS_I(inode)) == key.objectid) { 17225d4f98a2SYan Zheng end = key.offset + 17235d4f98a2SYan Zheng btrfs_file_extent_num_bytes(leaf, fi); 17245d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(key.offset, 17250b246afaSJeff Mahoney fs_info->sectorsize)); 17260b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 17275d4f98a2SYan Zheng end--; 17285d4f98a2SYan Zheng ret = try_lock_extent(&BTRFS_I(inode)->io_tree, 1729d0082371SJeff Mahoney key.offset, end); 17305d4f98a2SYan Zheng if (!ret) 17315d4f98a2SYan Zheng continue; 17325d4f98a2SYan Zheng 1733dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), 1734dcdbc059SNikolay Borisov key.offset, end, 1); 17355d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 1736d0082371SJeff Mahoney key.offset, end); 17375d4f98a2SYan Zheng } 17385d4f98a2SYan Zheng } 17395d4f98a2SYan Zheng 17405d4f98a2SYan Zheng ret = get_new_location(rc->data_inode, &new_bytenr, 17415d4f98a2SYan Zheng bytenr, num_bytes); 174283d4cfd4SJosef Bacik if (ret) { 174383d4cfd4SJosef Bacik /* 174483d4cfd4SJosef Bacik * Don't have to abort since we've not changed anything 174583d4cfd4SJosef Bacik * in the file extent yet. 174683d4cfd4SJosef Bacik */ 174783d4cfd4SJosef Bacik break; 17483fd0a558SYan, Zheng } 17495d4f98a2SYan Zheng 17505d4f98a2SYan Zheng btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); 17515d4f98a2SYan Zheng dirty = 1; 17525d4f98a2SYan Zheng 17535d4f98a2SYan Zheng key.offset -= btrfs_file_extent_offset(leaf, fi); 175482fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 175582fa113fSQu Wenruo num_bytes, parent); 175682fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 175782fa113fSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1758b06c4bf5SFilipe Manana key.objectid, key.offset); 175982fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 176083d4cfd4SJosef Bacik if (ret) { 176166642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 176283d4cfd4SJosef Bacik break; 176383d4cfd4SJosef Bacik } 17645d4f98a2SYan Zheng 1765ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr, 1766ffd4bb2aSQu Wenruo num_bytes, parent); 1767ffd4bb2aSQu Wenruo ref.real_root = root->root_key.objectid; 1768ffd4bb2aSQu Wenruo btrfs_init_data_ref(&ref, btrfs_header_owner(leaf), 1769b06c4bf5SFilipe Manana key.objectid, key.offset); 1770ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 177183d4cfd4SJosef Bacik if (ret) { 177266642832SJeff Mahoney btrfs_abort_transaction(trans, ret); 177383d4cfd4SJosef Bacik break; 177483d4cfd4SJosef Bacik } 17755d4f98a2SYan Zheng } 17765d4f98a2SYan Zheng if (dirty) 17775d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 17783fd0a558SYan, Zheng if (inode) 17793fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 178083d4cfd4SJosef Bacik return ret; 17815d4f98a2SYan Zheng } 17825d4f98a2SYan Zheng 17835d4f98a2SYan Zheng static noinline_for_stack 17845d4f98a2SYan Zheng int memcmp_node_keys(struct extent_buffer *eb, int slot, 17855d4f98a2SYan Zheng struct btrfs_path *path, int level) 17865d4f98a2SYan Zheng { 17875d4f98a2SYan Zheng struct btrfs_disk_key key1; 17885d4f98a2SYan Zheng struct btrfs_disk_key key2; 17895d4f98a2SYan Zheng btrfs_node_key(eb, &key1, slot); 17905d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &key2, path->slots[level]); 17915d4f98a2SYan Zheng return memcmp(&key1, &key2, sizeof(key1)); 17925d4f98a2SYan Zheng } 17935d4f98a2SYan Zheng 17945d4f98a2SYan Zheng /* 17955d4f98a2SYan Zheng * try to replace tree blocks in fs tree with the new blocks 17965d4f98a2SYan Zheng * in reloc tree. tree blocks haven't been modified since the 17975d4f98a2SYan Zheng * reloc tree was create can be replaced. 17985d4f98a2SYan Zheng * 17995d4f98a2SYan Zheng * if a block was replaced, level of the block + 1 is returned. 18005d4f98a2SYan Zheng * if no block got replaced, 0 is returned. if there are other 18015d4f98a2SYan Zheng * errors, a negative error number is returned. 18025d4f98a2SYan Zheng */ 18033fd0a558SYan, Zheng static noinline_for_stack 18043d0174f7SQu Wenruo int replace_path(struct btrfs_trans_handle *trans, struct reloc_control *rc, 18055d4f98a2SYan Zheng struct btrfs_root *dest, struct btrfs_root *src, 18065d4f98a2SYan Zheng struct btrfs_path *path, struct btrfs_key *next_key, 18075d4f98a2SYan Zheng int lowest_level, int max_level) 18085d4f98a2SYan Zheng { 18090b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = dest->fs_info; 18105d4f98a2SYan Zheng struct extent_buffer *eb; 18115d4f98a2SYan Zheng struct extent_buffer *parent; 181282fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 18135d4f98a2SYan Zheng struct btrfs_key key; 18145d4f98a2SYan Zheng u64 old_bytenr; 18155d4f98a2SYan Zheng u64 new_bytenr; 18165d4f98a2SYan Zheng u64 old_ptr_gen; 18175d4f98a2SYan Zheng u64 new_ptr_gen; 18185d4f98a2SYan Zheng u64 last_snapshot; 18195d4f98a2SYan Zheng u32 blocksize; 18203fd0a558SYan, Zheng int cow = 0; 18215d4f98a2SYan Zheng int level; 18225d4f98a2SYan Zheng int ret; 18235d4f98a2SYan Zheng int slot; 18245d4f98a2SYan Zheng 18255d4f98a2SYan Zheng BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 18265d4f98a2SYan Zheng BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); 18275d4f98a2SYan Zheng 18285d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&src->root_item); 18293fd0a558SYan, Zheng again: 18305d4f98a2SYan Zheng slot = path->slots[lowest_level]; 18315d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); 18325d4f98a2SYan Zheng 18335d4f98a2SYan Zheng eb = btrfs_lock_root_node(dest); 18348bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 18355d4f98a2SYan Zheng level = btrfs_header_level(eb); 18365d4f98a2SYan Zheng 18375d4f98a2SYan Zheng if (level < lowest_level) { 18385d4f98a2SYan Zheng btrfs_tree_unlock(eb); 18395d4f98a2SYan Zheng free_extent_buffer(eb); 18405d4f98a2SYan Zheng return 0; 18415d4f98a2SYan Zheng } 18425d4f98a2SYan Zheng 18433fd0a558SYan, Zheng if (cow) { 18445d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); 18455d4f98a2SYan Zheng BUG_ON(ret); 18463fd0a558SYan, Zheng } 18478bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 18485d4f98a2SYan Zheng 18495d4f98a2SYan Zheng if (next_key) { 18505d4f98a2SYan Zheng next_key->objectid = (u64)-1; 18515d4f98a2SYan Zheng next_key->type = (u8)-1; 18525d4f98a2SYan Zheng next_key->offset = (u64)-1; 18535d4f98a2SYan Zheng } 18545d4f98a2SYan Zheng 18555d4f98a2SYan Zheng parent = eb; 18565d4f98a2SYan Zheng while (1) { 1857581c1760SQu Wenruo struct btrfs_key first_key; 1858581c1760SQu Wenruo 18595d4f98a2SYan Zheng level = btrfs_header_level(parent); 18605d4f98a2SYan Zheng BUG_ON(level < lowest_level); 18615d4f98a2SYan Zheng 18625d4f98a2SYan Zheng ret = btrfs_bin_search(parent, &key, level, &slot); 1863cbca7d59SFilipe Manana if (ret < 0) 1864cbca7d59SFilipe Manana break; 18655d4f98a2SYan Zheng if (ret && slot > 0) 18665d4f98a2SYan Zheng slot--; 18675d4f98a2SYan Zheng 18685d4f98a2SYan Zheng if (next_key && slot + 1 < btrfs_header_nritems(parent)) 18695d4f98a2SYan Zheng btrfs_node_key_to_cpu(parent, next_key, slot + 1); 18705d4f98a2SYan Zheng 18715d4f98a2SYan Zheng old_bytenr = btrfs_node_blockptr(parent, slot); 18720b246afaSJeff Mahoney blocksize = fs_info->nodesize; 18735d4f98a2SYan Zheng old_ptr_gen = btrfs_node_ptr_generation(parent, slot); 187417515f1bSQu Wenruo btrfs_node_key_to_cpu(parent, &first_key, slot); 18755d4f98a2SYan Zheng 18765d4f98a2SYan Zheng if (level <= max_level) { 18775d4f98a2SYan Zheng eb = path->nodes[level]; 18785d4f98a2SYan Zheng new_bytenr = btrfs_node_blockptr(eb, 18795d4f98a2SYan Zheng path->slots[level]); 18805d4f98a2SYan Zheng new_ptr_gen = btrfs_node_ptr_generation(eb, 18815d4f98a2SYan Zheng path->slots[level]); 18825d4f98a2SYan Zheng } else { 18835d4f98a2SYan Zheng new_bytenr = 0; 18845d4f98a2SYan Zheng new_ptr_gen = 0; 18855d4f98a2SYan Zheng } 18865d4f98a2SYan Zheng 1887fae7f21cSDulshani Gunawardhana if (WARN_ON(new_bytenr > 0 && new_bytenr == old_bytenr)) { 18885d4f98a2SYan Zheng ret = level; 18895d4f98a2SYan Zheng break; 18905d4f98a2SYan Zheng } 18915d4f98a2SYan Zheng 18925d4f98a2SYan Zheng if (new_bytenr == 0 || old_ptr_gen > last_snapshot || 18935d4f98a2SYan Zheng memcmp_node_keys(parent, slot, path, level)) { 18943fd0a558SYan, Zheng if (level <= lowest_level) { 18955d4f98a2SYan Zheng ret = 0; 18965d4f98a2SYan Zheng break; 18975d4f98a2SYan Zheng } 18985d4f98a2SYan Zheng 1899581c1760SQu Wenruo eb = read_tree_block(fs_info, old_bytenr, old_ptr_gen, 1900581c1760SQu Wenruo level - 1, &first_key); 190164c043deSLiu Bo if (IS_ERR(eb)) { 190264c043deSLiu Bo ret = PTR_ERR(eb); 1903264813acSLiu Bo break; 190464c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 190564c043deSLiu Bo ret = -EIO; 1906416bc658SJosef Bacik free_extent_buffer(eb); 1907379cde74SStefan Behrens break; 1908416bc658SJosef Bacik } 19095d4f98a2SYan Zheng btrfs_tree_lock(eb); 19103fd0a558SYan, Zheng if (cow) { 19115d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, parent, 19125d4f98a2SYan Zheng slot, &eb); 19135d4f98a2SYan Zheng BUG_ON(ret); 19145d4f98a2SYan Zheng } 19158bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 19165d4f98a2SYan Zheng 19175d4f98a2SYan Zheng btrfs_tree_unlock(parent); 19185d4f98a2SYan Zheng free_extent_buffer(parent); 19195d4f98a2SYan Zheng 19205d4f98a2SYan Zheng parent = eb; 19215d4f98a2SYan Zheng continue; 19225d4f98a2SYan Zheng } 19235d4f98a2SYan Zheng 19243fd0a558SYan, Zheng if (!cow) { 19253fd0a558SYan, Zheng btrfs_tree_unlock(parent); 19263fd0a558SYan, Zheng free_extent_buffer(parent); 19273fd0a558SYan, Zheng cow = 1; 19283fd0a558SYan, Zheng goto again; 19293fd0a558SYan, Zheng } 19303fd0a558SYan, Zheng 19315d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 19325d4f98a2SYan Zheng path->slots[level]); 1933b3b4aa74SDavid Sterba btrfs_release_path(path); 19345d4f98a2SYan Zheng 19355d4f98a2SYan Zheng path->lowest_level = level; 19365d4f98a2SYan Zheng ret = btrfs_search_slot(trans, src, &key, path, 0, 1); 19375d4f98a2SYan Zheng path->lowest_level = 0; 19385d4f98a2SYan Zheng BUG_ON(ret); 19395d4f98a2SYan Zheng 19405d4f98a2SYan Zheng /* 1941824d8dffSQu Wenruo * Info qgroup to trace both subtrees. 1942824d8dffSQu Wenruo * 1943824d8dffSQu Wenruo * We must trace both trees. 1944824d8dffSQu Wenruo * 1) Tree reloc subtree 1945824d8dffSQu Wenruo * If not traced, we will leak data numbers 1946824d8dffSQu Wenruo * 2) Fs subtree 1947824d8dffSQu Wenruo * If not traced, we will double count old data 1948f616f5cdSQu Wenruo * 1949f616f5cdSQu Wenruo * We don't scan the subtree right now, but only record 1950f616f5cdSQu Wenruo * the swapped tree blocks. 1951f616f5cdSQu Wenruo * The real subtree rescan is delayed until we have new 1952f616f5cdSQu Wenruo * CoW on the subtree root node before transaction commit. 1953824d8dffSQu Wenruo */ 1954370a11b8SQu Wenruo ret = btrfs_qgroup_add_swapped_blocks(trans, dest, 1955370a11b8SQu Wenruo rc->block_group, parent, slot, 1956370a11b8SQu Wenruo path->nodes[level], path->slots[level], 1957370a11b8SQu Wenruo last_snapshot); 1958370a11b8SQu Wenruo if (ret < 0) 1959370a11b8SQu Wenruo break; 1960824d8dffSQu Wenruo /* 19615d4f98a2SYan Zheng * swap blocks in fs tree and reloc tree. 19625d4f98a2SYan Zheng */ 19635d4f98a2SYan Zheng btrfs_set_node_blockptr(parent, slot, new_bytenr); 19645d4f98a2SYan Zheng btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); 19655d4f98a2SYan Zheng btrfs_mark_buffer_dirty(parent); 19665d4f98a2SYan Zheng 19675d4f98a2SYan Zheng btrfs_set_node_blockptr(path->nodes[level], 19685d4f98a2SYan Zheng path->slots[level], old_bytenr); 19695d4f98a2SYan Zheng btrfs_set_node_ptr_generation(path->nodes[level], 19705d4f98a2SYan Zheng path->slots[level], old_ptr_gen); 19715d4f98a2SYan Zheng btrfs_mark_buffer_dirty(path->nodes[level]); 19725d4f98a2SYan Zheng 197382fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, old_bytenr, 197482fa113fSQu Wenruo blocksize, path->nodes[level]->start); 197582fa113fSQu Wenruo ref.skip_qgroup = true; 197682fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 197782fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 19785d4f98a2SYan Zheng BUG_ON(ret); 197982fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr, 198082fa113fSQu Wenruo blocksize, 0); 198182fa113fSQu Wenruo ref.skip_qgroup = true; 198282fa113fSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 198382fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 19845d4f98a2SYan Zheng BUG_ON(ret); 19855d4f98a2SYan Zheng 1986ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, new_bytenr, 1987ffd4bb2aSQu Wenruo blocksize, path->nodes[level]->start); 1988ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid); 1989ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 1990ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 19915d4f98a2SYan Zheng BUG_ON(ret); 19925d4f98a2SYan Zheng 1993ffd4bb2aSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, old_bytenr, 1994ffd4bb2aSQu Wenruo blocksize, 0); 1995ffd4bb2aSQu Wenruo btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid); 1996ffd4bb2aSQu Wenruo ref.skip_qgroup = true; 1997ffd4bb2aSQu Wenruo ret = btrfs_free_extent(trans, &ref); 19985d4f98a2SYan Zheng BUG_ON(ret); 19995d4f98a2SYan Zheng 20005d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 20015d4f98a2SYan Zheng 20025d4f98a2SYan Zheng ret = level; 20035d4f98a2SYan Zheng break; 20045d4f98a2SYan Zheng } 20055d4f98a2SYan Zheng btrfs_tree_unlock(parent); 20065d4f98a2SYan Zheng free_extent_buffer(parent); 20075d4f98a2SYan Zheng return ret; 20085d4f98a2SYan Zheng } 20095d4f98a2SYan Zheng 20105d4f98a2SYan Zheng /* 20115d4f98a2SYan Zheng * helper to find next relocated block in reloc tree 20125d4f98a2SYan Zheng */ 20135d4f98a2SYan Zheng static noinline_for_stack 20145d4f98a2SYan Zheng int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 20155d4f98a2SYan Zheng int *level) 20165d4f98a2SYan Zheng { 20175d4f98a2SYan Zheng struct extent_buffer *eb; 20185d4f98a2SYan Zheng int i; 20195d4f98a2SYan Zheng u64 last_snapshot; 20205d4f98a2SYan Zheng u32 nritems; 20215d4f98a2SYan Zheng 20225d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 20235d4f98a2SYan Zheng 20245d4f98a2SYan Zheng for (i = 0; i < *level; i++) { 20255d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 20265d4f98a2SYan Zheng path->nodes[i] = NULL; 20275d4f98a2SYan Zheng } 20285d4f98a2SYan Zheng 20295d4f98a2SYan Zheng for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { 20305d4f98a2SYan Zheng eb = path->nodes[i]; 20315d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 20325d4f98a2SYan Zheng while (path->slots[i] + 1 < nritems) { 20335d4f98a2SYan Zheng path->slots[i]++; 20345d4f98a2SYan Zheng if (btrfs_node_ptr_generation(eb, path->slots[i]) <= 20355d4f98a2SYan Zheng last_snapshot) 20365d4f98a2SYan Zheng continue; 20375d4f98a2SYan Zheng 20385d4f98a2SYan Zheng *level = i; 20395d4f98a2SYan Zheng return 0; 20405d4f98a2SYan Zheng } 20415d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 20425d4f98a2SYan Zheng path->nodes[i] = NULL; 20435d4f98a2SYan Zheng } 20445d4f98a2SYan Zheng return 1; 20455d4f98a2SYan Zheng } 20465d4f98a2SYan Zheng 20475d4f98a2SYan Zheng /* 20485d4f98a2SYan Zheng * walk down reloc tree to find relocated block of lowest level 20495d4f98a2SYan Zheng */ 20505d4f98a2SYan Zheng static noinline_for_stack 20515d4f98a2SYan Zheng int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 20525d4f98a2SYan Zheng int *level) 20535d4f98a2SYan Zheng { 20542ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 20555d4f98a2SYan Zheng struct extent_buffer *eb = NULL; 20565d4f98a2SYan Zheng int i; 20575d4f98a2SYan Zheng u64 bytenr; 20585d4f98a2SYan Zheng u64 ptr_gen = 0; 20595d4f98a2SYan Zheng u64 last_snapshot; 20605d4f98a2SYan Zheng u32 nritems; 20615d4f98a2SYan Zheng 20625d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 20635d4f98a2SYan Zheng 20645d4f98a2SYan Zheng for (i = *level; i > 0; i--) { 2065581c1760SQu Wenruo struct btrfs_key first_key; 2066581c1760SQu Wenruo 20675d4f98a2SYan Zheng eb = path->nodes[i]; 20685d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 20695d4f98a2SYan Zheng while (path->slots[i] < nritems) { 20705d4f98a2SYan Zheng ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); 20715d4f98a2SYan Zheng if (ptr_gen > last_snapshot) 20725d4f98a2SYan Zheng break; 20735d4f98a2SYan Zheng path->slots[i]++; 20745d4f98a2SYan Zheng } 20755d4f98a2SYan Zheng if (path->slots[i] >= nritems) { 20765d4f98a2SYan Zheng if (i == *level) 20775d4f98a2SYan Zheng break; 20785d4f98a2SYan Zheng *level = i + 1; 20795d4f98a2SYan Zheng return 0; 20805d4f98a2SYan Zheng } 20815d4f98a2SYan Zheng if (i == 1) { 20825d4f98a2SYan Zheng *level = i; 20835d4f98a2SYan Zheng return 0; 20845d4f98a2SYan Zheng } 20855d4f98a2SYan Zheng 20865d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(eb, path->slots[i]); 2087581c1760SQu Wenruo btrfs_node_key_to_cpu(eb, &first_key, path->slots[i]); 2088581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, ptr_gen, i - 1, 2089581c1760SQu Wenruo &first_key); 209064c043deSLiu Bo if (IS_ERR(eb)) { 209164c043deSLiu Bo return PTR_ERR(eb); 209264c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2093416bc658SJosef Bacik free_extent_buffer(eb); 2094416bc658SJosef Bacik return -EIO; 2095416bc658SJosef Bacik } 20965d4f98a2SYan Zheng BUG_ON(btrfs_header_level(eb) != i - 1); 20975d4f98a2SYan Zheng path->nodes[i - 1] = eb; 20985d4f98a2SYan Zheng path->slots[i - 1] = 0; 20995d4f98a2SYan Zheng } 21005d4f98a2SYan Zheng return 1; 21015d4f98a2SYan Zheng } 21025d4f98a2SYan Zheng 21035d4f98a2SYan Zheng /* 21045d4f98a2SYan Zheng * invalidate extent cache for file extents whose key in range of 21055d4f98a2SYan Zheng * [min_key, max_key) 21065d4f98a2SYan Zheng */ 21075d4f98a2SYan Zheng static int invalidate_extent_cache(struct btrfs_root *root, 21085d4f98a2SYan Zheng struct btrfs_key *min_key, 21095d4f98a2SYan Zheng struct btrfs_key *max_key) 21105d4f98a2SYan Zheng { 21110b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 21125d4f98a2SYan Zheng struct inode *inode = NULL; 21135d4f98a2SYan Zheng u64 objectid; 21145d4f98a2SYan Zheng u64 start, end; 211533345d01SLi Zefan u64 ino; 21165d4f98a2SYan Zheng 21175d4f98a2SYan Zheng objectid = min_key->objectid; 21185d4f98a2SYan Zheng while (1) { 21195d4f98a2SYan Zheng cond_resched(); 21205d4f98a2SYan Zheng iput(inode); 21215d4f98a2SYan Zheng 21225d4f98a2SYan Zheng if (objectid > max_key->objectid) 21235d4f98a2SYan Zheng break; 21245d4f98a2SYan Zheng 21255d4f98a2SYan Zheng inode = find_next_inode(root, objectid); 21265d4f98a2SYan Zheng if (!inode) 21275d4f98a2SYan Zheng break; 21284a0cc7caSNikolay Borisov ino = btrfs_ino(BTRFS_I(inode)); 21295d4f98a2SYan Zheng 213033345d01SLi Zefan if (ino > max_key->objectid) { 21315d4f98a2SYan Zheng iput(inode); 21325d4f98a2SYan Zheng break; 21335d4f98a2SYan Zheng } 21345d4f98a2SYan Zheng 213533345d01SLi Zefan objectid = ino + 1; 21365d4f98a2SYan Zheng if (!S_ISREG(inode->i_mode)) 21375d4f98a2SYan Zheng continue; 21385d4f98a2SYan Zheng 213933345d01SLi Zefan if (unlikely(min_key->objectid == ino)) { 21405d4f98a2SYan Zheng if (min_key->type > BTRFS_EXTENT_DATA_KEY) 21415d4f98a2SYan Zheng continue; 21425d4f98a2SYan Zheng if (min_key->type < BTRFS_EXTENT_DATA_KEY) 21435d4f98a2SYan Zheng start = 0; 21445d4f98a2SYan Zheng else { 21455d4f98a2SYan Zheng start = min_key->offset; 21460b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(start, fs_info->sectorsize)); 21475d4f98a2SYan Zheng } 21485d4f98a2SYan Zheng } else { 21495d4f98a2SYan Zheng start = 0; 21505d4f98a2SYan Zheng } 21515d4f98a2SYan Zheng 215233345d01SLi Zefan if (unlikely(max_key->objectid == ino)) { 21535d4f98a2SYan Zheng if (max_key->type < BTRFS_EXTENT_DATA_KEY) 21545d4f98a2SYan Zheng continue; 21555d4f98a2SYan Zheng if (max_key->type > BTRFS_EXTENT_DATA_KEY) { 21565d4f98a2SYan Zheng end = (u64)-1; 21575d4f98a2SYan Zheng } else { 21585d4f98a2SYan Zheng if (max_key->offset == 0) 21595d4f98a2SYan Zheng continue; 21605d4f98a2SYan Zheng end = max_key->offset; 21610b246afaSJeff Mahoney WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize)); 21625d4f98a2SYan Zheng end--; 21635d4f98a2SYan Zheng } 21645d4f98a2SYan Zheng } else { 21655d4f98a2SYan Zheng end = (u64)-1; 21665d4f98a2SYan Zheng } 21675d4f98a2SYan Zheng 21685d4f98a2SYan Zheng /* the lock_extent waits for readpage to complete */ 2169d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 2170dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 1); 2171d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 21725d4f98a2SYan Zheng } 21735d4f98a2SYan Zheng return 0; 21745d4f98a2SYan Zheng } 21755d4f98a2SYan Zheng 21765d4f98a2SYan Zheng static int find_next_key(struct btrfs_path *path, int level, 21775d4f98a2SYan Zheng struct btrfs_key *key) 21785d4f98a2SYan Zheng 21795d4f98a2SYan Zheng { 21805d4f98a2SYan Zheng while (level < BTRFS_MAX_LEVEL) { 21815d4f98a2SYan Zheng if (!path->nodes[level]) 21825d4f98a2SYan Zheng break; 21835d4f98a2SYan Zheng if (path->slots[level] + 1 < 21845d4f98a2SYan Zheng btrfs_header_nritems(path->nodes[level])) { 21855d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], key, 21865d4f98a2SYan Zheng path->slots[level] + 1); 21875d4f98a2SYan Zheng return 0; 21885d4f98a2SYan Zheng } 21895d4f98a2SYan Zheng level++; 21905d4f98a2SYan Zheng } 21915d4f98a2SYan Zheng return 1; 21925d4f98a2SYan Zheng } 21935d4f98a2SYan Zheng 21945d4f98a2SYan Zheng /* 2195d2311e69SQu Wenruo * Insert current subvolume into reloc_control::dirty_subvol_roots 2196d2311e69SQu Wenruo */ 2197d2311e69SQu Wenruo static void insert_dirty_subvol(struct btrfs_trans_handle *trans, 2198d2311e69SQu Wenruo struct reloc_control *rc, 2199d2311e69SQu Wenruo struct btrfs_root *root) 2200d2311e69SQu Wenruo { 2201d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2202d2311e69SQu Wenruo struct btrfs_root_item *reloc_root_item; 2203d2311e69SQu Wenruo 2204d2311e69SQu Wenruo /* @root must be a subvolume tree root with a valid reloc tree */ 2205d2311e69SQu Wenruo ASSERT(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 2206d2311e69SQu Wenruo ASSERT(reloc_root); 2207d2311e69SQu Wenruo 2208d2311e69SQu Wenruo reloc_root_item = &reloc_root->root_item; 2209d2311e69SQu Wenruo memset(&reloc_root_item->drop_progress, 0, 2210d2311e69SQu Wenruo sizeof(reloc_root_item->drop_progress)); 2211d2311e69SQu Wenruo reloc_root_item->drop_level = 0; 2212d2311e69SQu Wenruo btrfs_set_root_refs(reloc_root_item, 0); 2213d2311e69SQu Wenruo btrfs_update_reloc_root(trans, root); 2214d2311e69SQu Wenruo 2215d2311e69SQu Wenruo if (list_empty(&root->reloc_dirty_list)) { 221600246528SJosef Bacik btrfs_grab_root(root); 2217d2311e69SQu Wenruo list_add_tail(&root->reloc_dirty_list, &rc->dirty_subvol_roots); 2218d2311e69SQu Wenruo } 2219d2311e69SQu Wenruo } 2220d2311e69SQu Wenruo 2221d2311e69SQu Wenruo static int clean_dirty_subvols(struct reloc_control *rc) 2222d2311e69SQu Wenruo { 2223d2311e69SQu Wenruo struct btrfs_root *root; 2224d2311e69SQu Wenruo struct btrfs_root *next; 2225d2311e69SQu Wenruo int ret = 0; 222630d40577SQu Wenruo int ret2; 2227d2311e69SQu Wenruo 2228d2311e69SQu Wenruo list_for_each_entry_safe(root, next, &rc->dirty_subvol_roots, 2229d2311e69SQu Wenruo reloc_dirty_list) { 223030d40577SQu Wenruo if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 223130d40577SQu Wenruo /* Merged subvolume, cleanup its reloc root */ 2232d2311e69SQu Wenruo struct btrfs_root *reloc_root = root->reloc_root; 2233d2311e69SQu Wenruo 2234d2311e69SQu Wenruo list_del_init(&root->reloc_dirty_list); 2235d2311e69SQu Wenruo root->reloc_root = NULL; 22366282675eSQu Wenruo /* 22376282675eSQu Wenruo * Need barrier to ensure clear_bit() only happens after 22386282675eSQu Wenruo * root->reloc_root = NULL. Pairs with have_reloc_root. 22396282675eSQu Wenruo */ 22406282675eSQu Wenruo smp_wmb(); 22411fac4a54SQu Wenruo clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state); 2242f28de8d8SJosef Bacik if (reloc_root) { 2243f44deb74SJosef Bacik /* 2244f44deb74SJosef Bacik * btrfs_drop_snapshot drops our ref we hold for 2245f44deb74SJosef Bacik * ->reloc_root. If it fails however we must 2246f44deb74SJosef Bacik * drop the ref ourselves. 2247f44deb74SJosef Bacik */ 2248f28de8d8SJosef Bacik ret2 = btrfs_drop_snapshot(reloc_root, 0, 1); 2249f44deb74SJosef Bacik if (ret2 < 0) { 2250f44deb74SJosef Bacik btrfs_put_root(reloc_root); 2251f44deb74SJosef Bacik if (!ret) 2252f28de8d8SJosef Bacik ret = ret2; 2253f28de8d8SJosef Bacik } 2254f44deb74SJosef Bacik } 225500246528SJosef Bacik btrfs_put_root(root); 225630d40577SQu Wenruo } else { 225730d40577SQu Wenruo /* Orphan reloc tree, just clean it up */ 22580078a9f9SNikolay Borisov ret2 = btrfs_drop_snapshot(root, 0, 1); 2259f44deb74SJosef Bacik if (ret2 < 0) { 2260f44deb74SJosef Bacik btrfs_put_root(root); 2261f44deb74SJosef Bacik if (!ret) 226230d40577SQu Wenruo ret = ret2; 226330d40577SQu Wenruo } 2264d2311e69SQu Wenruo } 2265f44deb74SJosef Bacik } 2266d2311e69SQu Wenruo return ret; 2267d2311e69SQu Wenruo } 2268d2311e69SQu Wenruo 2269d2311e69SQu Wenruo /* 22705d4f98a2SYan Zheng * merge the relocated tree blocks in reloc tree with corresponding 22715d4f98a2SYan Zheng * fs tree. 22725d4f98a2SYan Zheng */ 22735d4f98a2SYan Zheng static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, 22745d4f98a2SYan Zheng struct btrfs_root *root) 22755d4f98a2SYan Zheng { 22760b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 22775d4f98a2SYan Zheng struct btrfs_key key; 22785d4f98a2SYan Zheng struct btrfs_key next_key; 22799e6a0c52SJosef Bacik struct btrfs_trans_handle *trans = NULL; 22805d4f98a2SYan Zheng struct btrfs_root *reloc_root; 22815d4f98a2SYan Zheng struct btrfs_root_item *root_item; 22825d4f98a2SYan Zheng struct btrfs_path *path; 22833fd0a558SYan, Zheng struct extent_buffer *leaf; 22845d4f98a2SYan Zheng int level; 22855d4f98a2SYan Zheng int max_level; 22865d4f98a2SYan Zheng int replaced = 0; 22875d4f98a2SYan Zheng int ret; 22885d4f98a2SYan Zheng int err = 0; 22893fd0a558SYan, Zheng u32 min_reserved; 22905d4f98a2SYan Zheng 22915d4f98a2SYan Zheng path = btrfs_alloc_path(); 22925d4f98a2SYan Zheng if (!path) 22935d4f98a2SYan Zheng return -ENOMEM; 2294e4058b54SDavid Sterba path->reada = READA_FORWARD; 22955d4f98a2SYan Zheng 22965d4f98a2SYan Zheng reloc_root = root->reloc_root; 22975d4f98a2SYan Zheng root_item = &reloc_root->root_item; 22985d4f98a2SYan Zheng 22995d4f98a2SYan Zheng if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { 23005d4f98a2SYan Zheng level = btrfs_root_level(root_item); 230167439dadSDavid Sterba atomic_inc(&reloc_root->node->refs); 23025d4f98a2SYan Zheng path->nodes[level] = reloc_root->node; 23035d4f98a2SYan Zheng path->slots[level] = 0; 23045d4f98a2SYan Zheng } else { 23055d4f98a2SYan Zheng btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); 23065d4f98a2SYan Zheng 23075d4f98a2SYan Zheng level = root_item->drop_level; 23085d4f98a2SYan Zheng BUG_ON(level == 0); 23095d4f98a2SYan Zheng path->lowest_level = level; 23105d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); 231133c66f43SYan Zheng path->lowest_level = 0; 23125d4f98a2SYan Zheng if (ret < 0) { 23135d4f98a2SYan Zheng btrfs_free_path(path); 23145d4f98a2SYan Zheng return ret; 23155d4f98a2SYan Zheng } 23165d4f98a2SYan Zheng 23175d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &next_key, 23185d4f98a2SYan Zheng path->slots[level]); 23195d4f98a2SYan Zheng WARN_ON(memcmp(&key, &next_key, sizeof(key))); 23205d4f98a2SYan Zheng 23215d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 23225d4f98a2SYan Zheng } 23235d4f98a2SYan Zheng 23240b246afaSJeff Mahoney min_reserved = fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 23255d4f98a2SYan Zheng memset(&next_key, 0, sizeof(next_key)); 23265d4f98a2SYan Zheng 23275d4f98a2SYan Zheng while (1) { 232808e007d2SMiao Xie ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved, 232908e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 23303fd0a558SYan, Zheng if (ret) { 23319e6a0c52SJosef Bacik err = ret; 23329e6a0c52SJosef Bacik goto out; 23333fd0a558SYan, Zheng } 23349e6a0c52SJosef Bacik trans = btrfs_start_transaction(root, 0); 23359e6a0c52SJosef Bacik if (IS_ERR(trans)) { 23369e6a0c52SJosef Bacik err = PTR_ERR(trans); 23379e6a0c52SJosef Bacik trans = NULL; 23389e6a0c52SJosef Bacik goto out; 23399e6a0c52SJosef Bacik } 23402abc726aSJosef Bacik 23412abc726aSJosef Bacik /* 23422abc726aSJosef Bacik * At this point we no longer have a reloc_control, so we can't 23432abc726aSJosef Bacik * depend on btrfs_init_reloc_root to update our last_trans. 23442abc726aSJosef Bacik * 23452abc726aSJosef Bacik * But that's ok, we started the trans handle on our 23462abc726aSJosef Bacik * corresponding fs_root, which means it's been added to the 23472abc726aSJosef Bacik * dirty list. At commit time we'll still call 23482abc726aSJosef Bacik * btrfs_update_reloc_root() and update our root item 23492abc726aSJosef Bacik * appropriately. 23502abc726aSJosef Bacik */ 23512abc726aSJosef Bacik reloc_root->last_trans = trans->transid; 23529e6a0c52SJosef Bacik trans->block_rsv = rc->block_rsv; 23533fd0a558SYan, Zheng 23543fd0a558SYan, Zheng replaced = 0; 23555d4f98a2SYan Zheng max_level = level; 23565d4f98a2SYan Zheng 23575d4f98a2SYan Zheng ret = walk_down_reloc_tree(reloc_root, path, &level); 23585d4f98a2SYan Zheng if (ret < 0) { 23595d4f98a2SYan Zheng err = ret; 23605d4f98a2SYan Zheng goto out; 23615d4f98a2SYan Zheng } 23625d4f98a2SYan Zheng if (ret > 0) 23635d4f98a2SYan Zheng break; 23645d4f98a2SYan Zheng 23655d4f98a2SYan Zheng if (!find_next_key(path, level, &key) && 23665d4f98a2SYan Zheng btrfs_comp_cpu_keys(&next_key, &key) >= 0) { 23675d4f98a2SYan Zheng ret = 0; 23685d4f98a2SYan Zheng } else { 23693d0174f7SQu Wenruo ret = replace_path(trans, rc, root, reloc_root, path, 23703fd0a558SYan, Zheng &next_key, level, max_level); 23715d4f98a2SYan Zheng } 23725d4f98a2SYan Zheng if (ret < 0) { 23735d4f98a2SYan Zheng err = ret; 23745d4f98a2SYan Zheng goto out; 23755d4f98a2SYan Zheng } 23765d4f98a2SYan Zheng 23775d4f98a2SYan Zheng if (ret > 0) { 23785d4f98a2SYan Zheng level = ret; 23795d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 23805d4f98a2SYan Zheng path->slots[level]); 23815d4f98a2SYan Zheng replaced = 1; 23825d4f98a2SYan Zheng } 23835d4f98a2SYan Zheng 23845d4f98a2SYan Zheng ret = walk_up_reloc_tree(reloc_root, path, &level); 23855d4f98a2SYan Zheng if (ret > 0) 23865d4f98a2SYan Zheng break; 23875d4f98a2SYan Zheng 23885d4f98a2SYan Zheng BUG_ON(level == 0); 23895d4f98a2SYan Zheng /* 23905d4f98a2SYan Zheng * save the merging progress in the drop_progress. 23915d4f98a2SYan Zheng * this is OK since root refs == 1 in this case. 23925d4f98a2SYan Zheng */ 23935d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &root_item->drop_progress, 23945d4f98a2SYan Zheng path->slots[level]); 23955d4f98a2SYan Zheng root_item->drop_level = level; 23965d4f98a2SYan Zheng 23973a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 23989e6a0c52SJosef Bacik trans = NULL; 23995d4f98a2SYan Zheng 24002ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 24015d4f98a2SYan Zheng 24025d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 24035d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 24045d4f98a2SYan Zheng } 24055d4f98a2SYan Zheng 24065d4f98a2SYan Zheng /* 24075d4f98a2SYan Zheng * handle the case only one block in the fs tree need to be 24085d4f98a2SYan Zheng * relocated and the block is tree root. 24095d4f98a2SYan Zheng */ 24105d4f98a2SYan Zheng leaf = btrfs_lock_root_node(root); 24115d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); 24125d4f98a2SYan Zheng btrfs_tree_unlock(leaf); 24135d4f98a2SYan Zheng free_extent_buffer(leaf); 24145d4f98a2SYan Zheng if (ret < 0) 24155d4f98a2SYan Zheng err = ret; 24165d4f98a2SYan Zheng out: 24175d4f98a2SYan Zheng btrfs_free_path(path); 24185d4f98a2SYan Zheng 2419d2311e69SQu Wenruo if (err == 0) 2420d2311e69SQu Wenruo insert_dirty_subvol(trans, rc, root); 24215d4f98a2SYan Zheng 24229e6a0c52SJosef Bacik if (trans) 24233a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 24245d4f98a2SYan Zheng 24252ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 24265d4f98a2SYan Zheng 24275d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 24285d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 24295d4f98a2SYan Zheng 24305d4f98a2SYan Zheng return err; 24315d4f98a2SYan Zheng } 24325d4f98a2SYan Zheng 24333fd0a558SYan, Zheng static noinline_for_stack 24343fd0a558SYan, Zheng int prepare_to_merge(struct reloc_control *rc, int err) 24355d4f98a2SYan Zheng { 24363fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 24370b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 24383fd0a558SYan, Zheng struct btrfs_root *reloc_root; 24395d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 24403fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 24413fd0a558SYan, Zheng u64 num_bytes = 0; 24423fd0a558SYan, Zheng int ret; 24433fd0a558SYan, Zheng 24440b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 24450b246afaSJeff Mahoney rc->merging_rsv_size += fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 24463fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated * 2; 24470b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 24487585717fSChris Mason 24493fd0a558SYan, Zheng again: 24503fd0a558SYan, Zheng if (!err) { 24513fd0a558SYan, Zheng num_bytes = rc->merging_rsv_size; 245208e007d2SMiao Xie ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes, 245308e007d2SMiao Xie BTRFS_RESERVE_FLUSH_ALL); 24543fd0a558SYan, Zheng if (ret) 24553fd0a558SYan, Zheng err = ret; 24563fd0a558SYan, Zheng } 24573fd0a558SYan, Zheng 24587a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 24593612b495STsutomu Itoh if (IS_ERR(trans)) { 24603612b495STsutomu Itoh if (!err) 24612ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 246263f018beSNikolay Borisov num_bytes, NULL); 24633612b495STsutomu Itoh return PTR_ERR(trans); 24643612b495STsutomu Itoh } 24653fd0a558SYan, Zheng 24663fd0a558SYan, Zheng if (!err) { 24673fd0a558SYan, Zheng if (num_bytes != rc->merging_rsv_size) { 24683a45bb20SJeff Mahoney btrfs_end_transaction(trans); 24692ff7e61eSJeff Mahoney btrfs_block_rsv_release(fs_info, rc->block_rsv, 247063f018beSNikolay Borisov num_bytes, NULL); 24713fd0a558SYan, Zheng goto again; 24723fd0a558SYan, Zheng } 24733fd0a558SYan, Zheng } 24743fd0a558SYan, Zheng 24753fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 24763fd0a558SYan, Zheng 24773fd0a558SYan, Zheng while (!list_empty(&rc->reloc_roots)) { 24783fd0a558SYan, Zheng reloc_root = list_entry(rc->reloc_roots.next, 24793fd0a558SYan, Zheng struct btrfs_root, root_list); 24803fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 24813fd0a558SYan, Zheng 24820b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 24833fd0a558SYan, Zheng BUG_ON(IS_ERR(root)); 24843fd0a558SYan, Zheng BUG_ON(root->reloc_root != reloc_root); 24853fd0a558SYan, Zheng 24863fd0a558SYan, Zheng /* 24873fd0a558SYan, Zheng * set reference count to 1, so btrfs_recover_relocation 24883fd0a558SYan, Zheng * knows it should resumes merging 24893fd0a558SYan, Zheng */ 24903fd0a558SYan, Zheng if (!err) 24913fd0a558SYan, Zheng btrfs_set_root_refs(&reloc_root->root_item, 1); 24923fd0a558SYan, Zheng btrfs_update_reloc_root(trans, root); 24933fd0a558SYan, Zheng 24943fd0a558SYan, Zheng list_add(&reloc_root->root_list, &reloc_roots); 249500246528SJosef Bacik btrfs_put_root(root); 24963fd0a558SYan, Zheng } 24973fd0a558SYan, Zheng 24983fd0a558SYan, Zheng list_splice(&reloc_roots, &rc->reloc_roots); 24993fd0a558SYan, Zheng 25003fd0a558SYan, Zheng if (!err) 25013a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 25023fd0a558SYan, Zheng else 25033a45bb20SJeff Mahoney btrfs_end_transaction(trans); 25043fd0a558SYan, Zheng return err; 25053fd0a558SYan, Zheng } 25063fd0a558SYan, Zheng 25073fd0a558SYan, Zheng static noinline_for_stack 2508aca1bba6SLiu Bo void free_reloc_roots(struct list_head *list) 2509aca1bba6SLiu Bo { 2510aca1bba6SLiu Bo struct btrfs_root *reloc_root; 2511aca1bba6SLiu Bo 2512aca1bba6SLiu Bo while (!list_empty(list)) { 2513aca1bba6SLiu Bo reloc_root = list_entry(list->next, struct btrfs_root, 2514aca1bba6SLiu Bo root_list); 2515bb166d72SNaohiro Aota __del_reloc_root(reloc_root); 2516aca1bba6SLiu Bo } 2517aca1bba6SLiu Bo } 2518aca1bba6SLiu Bo 2519aca1bba6SLiu Bo static noinline_for_stack 252094404e82SDavid Sterba void merge_reloc_roots(struct reloc_control *rc) 25213fd0a558SYan, Zheng { 25220b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 25235d4f98a2SYan Zheng struct btrfs_root *root; 25245d4f98a2SYan Zheng struct btrfs_root *reloc_root; 25253fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 25263fd0a558SYan, Zheng int found = 0; 2527aca1bba6SLiu Bo int ret = 0; 25283fd0a558SYan, Zheng again: 25293fd0a558SYan, Zheng root = rc->extent_root; 25307585717fSChris Mason 25317585717fSChris Mason /* 25327585717fSChris Mason * this serializes us with btrfs_record_root_in_transaction, 25337585717fSChris Mason * we have to make sure nobody is in the middle of 25347585717fSChris Mason * adding their roots to the list while we are 25357585717fSChris Mason * doing this splice 25367585717fSChris Mason */ 25370b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 25383fd0a558SYan, Zheng list_splice_init(&rc->reloc_roots, &reloc_roots); 25390b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 25405d4f98a2SYan Zheng 25413fd0a558SYan, Zheng while (!list_empty(&reloc_roots)) { 25423fd0a558SYan, Zheng found = 1; 25433fd0a558SYan, Zheng reloc_root = list_entry(reloc_roots.next, 25443fd0a558SYan, Zheng struct btrfs_root, root_list); 25455d4f98a2SYan Zheng 25465d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 25470b246afaSJeff Mahoney root = read_fs_root(fs_info, 25485d4f98a2SYan Zheng reloc_root->root_key.offset); 25495d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 25505d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 25515d4f98a2SYan Zheng 25523fd0a558SYan, Zheng ret = merge_reloc_root(rc, root); 255300246528SJosef Bacik btrfs_put_root(root); 2554b37b39cdSJosef Bacik if (ret) { 255525e293c2SWang Shilong if (list_empty(&reloc_root->root_list)) 255625e293c2SWang Shilong list_add_tail(&reloc_root->root_list, 255725e293c2SWang Shilong &reloc_roots); 2558aca1bba6SLiu Bo goto out; 2559b37b39cdSJosef Bacik } 25603fd0a558SYan, Zheng } else { 25613fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 256230d40577SQu Wenruo /* Don't forget to queue this reloc root for cleanup */ 256330d40577SQu Wenruo list_add_tail(&reloc_root->reloc_dirty_list, 256430d40577SQu Wenruo &rc->dirty_subvol_roots); 25653fd0a558SYan, Zheng } 25665d4f98a2SYan Zheng } 25675d4f98a2SYan Zheng 25683fd0a558SYan, Zheng if (found) { 25693fd0a558SYan, Zheng found = 0; 25703fd0a558SYan, Zheng goto again; 25715d4f98a2SYan Zheng } 2572aca1bba6SLiu Bo out: 2573aca1bba6SLiu Bo if (ret) { 25740b246afaSJeff Mahoney btrfs_handle_fs_error(fs_info, ret, NULL); 2575aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 2576aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 2577467bb1d2SWang Shilong 2578467bb1d2SWang Shilong /* new reloc root may be added */ 25790b246afaSJeff Mahoney mutex_lock(&fs_info->reloc_mutex); 2580467bb1d2SWang Shilong list_splice_init(&rc->reloc_roots, &reloc_roots); 25810b246afaSJeff Mahoney mutex_unlock(&fs_info->reloc_mutex); 2582467bb1d2SWang Shilong if (!list_empty(&reloc_roots)) 2583467bb1d2SWang Shilong free_reloc_roots(&reloc_roots); 2584aca1bba6SLiu Bo } 2585aca1bba6SLiu Bo 25867b7b7431SJosef Bacik /* 25877b7b7431SJosef Bacik * We used to have 25887b7b7431SJosef Bacik * 25897b7b7431SJosef Bacik * BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); 25907b7b7431SJosef Bacik * 25917b7b7431SJosef Bacik * here, but it's wrong. If we fail to start the transaction in 25927b7b7431SJosef Bacik * prepare_to_merge() we will have only 0 ref reloc roots, none of which 25937b7b7431SJosef Bacik * have actually been removed from the reloc_root_tree rb tree. This is 25947b7b7431SJosef Bacik * fine because we're bailing here, and we hold a reference on the root 25957b7b7431SJosef Bacik * for the list that holds it, so these roots will be cleaned up when we 25967b7b7431SJosef Bacik * do the reloc_dirty_list afterwards. Meanwhile the root->reloc_root 25977b7b7431SJosef Bacik * will be cleaned up on unmount. 25987b7b7431SJosef Bacik * 25997b7b7431SJosef Bacik * The remaining nodes will be cleaned up by free_reloc_control. 26007b7b7431SJosef Bacik */ 26015d4f98a2SYan Zheng } 26025d4f98a2SYan Zheng 26035d4f98a2SYan Zheng static void free_block_list(struct rb_root *blocks) 26045d4f98a2SYan Zheng { 26055d4f98a2SYan Zheng struct tree_block *block; 26065d4f98a2SYan Zheng struct rb_node *rb_node; 26075d4f98a2SYan Zheng while ((rb_node = rb_first(blocks))) { 26085d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 26095d4f98a2SYan Zheng rb_erase(rb_node, blocks); 26105d4f98a2SYan Zheng kfree(block); 26115d4f98a2SYan Zheng } 26125d4f98a2SYan Zheng } 26135d4f98a2SYan Zheng 26145d4f98a2SYan Zheng static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, 26155d4f98a2SYan Zheng struct btrfs_root *reloc_root) 26165d4f98a2SYan Zheng { 26170b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = reloc_root->fs_info; 26185d4f98a2SYan Zheng struct btrfs_root *root; 2619442b1ac5SJosef Bacik int ret; 26205d4f98a2SYan Zheng 26215d4f98a2SYan Zheng if (reloc_root->last_trans == trans->transid) 26225d4f98a2SYan Zheng return 0; 26235d4f98a2SYan Zheng 26240b246afaSJeff Mahoney root = read_fs_root(fs_info, reloc_root->root_key.offset); 26255d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 26265d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 2627442b1ac5SJosef Bacik ret = btrfs_record_root_in_trans(trans, root); 262800246528SJosef Bacik btrfs_put_root(root); 26295d4f98a2SYan Zheng 2630442b1ac5SJosef Bacik return ret; 26315d4f98a2SYan Zheng } 26325d4f98a2SYan Zheng 26333fd0a558SYan, Zheng static noinline_for_stack 26343fd0a558SYan, Zheng struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, 26353fd0a558SYan, Zheng struct reloc_control *rc, 2636a26195a5SQu Wenruo struct btrfs_backref_node *node, 2637a26195a5SQu Wenruo struct btrfs_backref_edge *edges[]) 26385d4f98a2SYan Zheng { 2639a26195a5SQu Wenruo struct btrfs_backref_node *next; 26405d4f98a2SYan Zheng struct btrfs_root *root; 26413fd0a558SYan, Zheng int index = 0; 26423fd0a558SYan, Zheng 26435d4f98a2SYan Zheng next = node; 26445d4f98a2SYan Zheng while (1) { 26455d4f98a2SYan Zheng cond_resched(); 26465d4f98a2SYan Zheng next = walk_up_backref(next, edges, &index); 26475d4f98a2SYan Zheng root = next->root; 26483fd0a558SYan, Zheng BUG_ON(!root); 264927cdeb70SMiao Xie BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS, &root->state)); 26505d4f98a2SYan Zheng 26515d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { 26525d4f98a2SYan Zheng record_reloc_root_in_trans(trans, root); 26535d4f98a2SYan Zheng break; 26545d4f98a2SYan Zheng } 26555d4f98a2SYan Zheng 26565d4f98a2SYan Zheng btrfs_record_root_in_trans(trans, root); 26573fd0a558SYan, Zheng root = root->reloc_root; 26583fd0a558SYan, Zheng 26593fd0a558SYan, Zheng if (next->new_bytenr != root->node->start) { 26603fd0a558SYan, Zheng BUG_ON(next->new_bytenr); 26613fd0a558SYan, Zheng BUG_ON(!list_empty(&next->list)); 26623fd0a558SYan, Zheng next->new_bytenr = root->node->start; 266300246528SJosef Bacik btrfs_put_root(next->root); 266400246528SJosef Bacik next->root = btrfs_grab_root(root); 26650b530bc5SJosef Bacik ASSERT(next->root); 26663fd0a558SYan, Zheng list_add_tail(&next->list, 26673fd0a558SYan, Zheng &rc->backref_cache.changed); 26689569cc20SQu Wenruo mark_block_processed(rc, next); 26695d4f98a2SYan Zheng break; 26705d4f98a2SYan Zheng } 26715d4f98a2SYan Zheng 26723fd0a558SYan, Zheng WARN_ON(1); 26735d4f98a2SYan Zheng root = NULL; 26745d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 26755d4f98a2SYan Zheng if (!next || next->level <= node->level) 26765d4f98a2SYan Zheng break; 26775d4f98a2SYan Zheng } 26783fd0a558SYan, Zheng if (!root) 26793fd0a558SYan, Zheng return NULL; 26805d4f98a2SYan Zheng 26813fd0a558SYan, Zheng next = node; 26823fd0a558SYan, Zheng /* setup backref node path for btrfs_reloc_cow_block */ 26833fd0a558SYan, Zheng while (1) { 26843fd0a558SYan, Zheng rc->backref_cache.path[next->level] = next; 26853fd0a558SYan, Zheng if (--index < 0) 26863fd0a558SYan, Zheng break; 26873fd0a558SYan, Zheng next = edges[index]->node[UPPER]; 26883fd0a558SYan, Zheng } 26895d4f98a2SYan Zheng return root; 26905d4f98a2SYan Zheng } 26915d4f98a2SYan Zheng 26923fd0a558SYan, Zheng /* 26933fd0a558SYan, Zheng * select a tree root for relocation. return NULL if the block 26943fd0a558SYan, Zheng * is reference counted. we should use do_relocation() in this 26953fd0a558SYan, Zheng * case. return a tree root pointer if the block isn't reference 26963fd0a558SYan, Zheng * counted. return -ENOENT if the block is root of reloc tree. 26973fd0a558SYan, Zheng */ 26985d4f98a2SYan Zheng static noinline_for_stack 2699a26195a5SQu Wenruo struct btrfs_root *select_one_root(struct btrfs_backref_node *node) 27005d4f98a2SYan Zheng { 2701a26195a5SQu Wenruo struct btrfs_backref_node *next; 27023fd0a558SYan, Zheng struct btrfs_root *root; 27033fd0a558SYan, Zheng struct btrfs_root *fs_root = NULL; 2704a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 27053fd0a558SYan, Zheng int index = 0; 27063fd0a558SYan, Zheng 27073fd0a558SYan, Zheng next = node; 27083fd0a558SYan, Zheng while (1) { 27093fd0a558SYan, Zheng cond_resched(); 27103fd0a558SYan, Zheng next = walk_up_backref(next, edges, &index); 27113fd0a558SYan, Zheng root = next->root; 27123fd0a558SYan, Zheng BUG_ON(!root); 27133fd0a558SYan, Zheng 271425985edcSLucas De Marchi /* no other choice for non-references counted tree */ 271527cdeb70SMiao Xie if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) 27163fd0a558SYan, Zheng return root; 27173fd0a558SYan, Zheng 27183fd0a558SYan, Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) 27193fd0a558SYan, Zheng fs_root = root; 27203fd0a558SYan, Zheng 27213fd0a558SYan, Zheng if (next != node) 27223fd0a558SYan, Zheng return NULL; 27233fd0a558SYan, Zheng 27243fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 27253fd0a558SYan, Zheng if (!next || next->level <= node->level) 27263fd0a558SYan, Zheng break; 27273fd0a558SYan, Zheng } 27283fd0a558SYan, Zheng 27293fd0a558SYan, Zheng if (!fs_root) 27303fd0a558SYan, Zheng return ERR_PTR(-ENOENT); 27313fd0a558SYan, Zheng return fs_root; 27325d4f98a2SYan Zheng } 27335d4f98a2SYan Zheng 27345d4f98a2SYan Zheng static noinline_for_stack 27353fd0a558SYan, Zheng u64 calcu_metadata_size(struct reloc_control *rc, 2736a26195a5SQu Wenruo struct btrfs_backref_node *node, int reserve) 27375d4f98a2SYan Zheng { 27380b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 2739a26195a5SQu Wenruo struct btrfs_backref_node *next = node; 2740a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2741a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 27423fd0a558SYan, Zheng u64 num_bytes = 0; 27433fd0a558SYan, Zheng int index = 0; 27445d4f98a2SYan Zheng 27453fd0a558SYan, Zheng BUG_ON(reserve && node->processed); 27463fd0a558SYan, Zheng 27473fd0a558SYan, Zheng while (next) { 27483fd0a558SYan, Zheng cond_resched(); 27495d4f98a2SYan Zheng while (1) { 27503fd0a558SYan, Zheng if (next->processed && (reserve || next != node)) 27515d4f98a2SYan Zheng break; 27525d4f98a2SYan Zheng 27530b246afaSJeff Mahoney num_bytes += fs_info->nodesize; 27543fd0a558SYan, Zheng 27553fd0a558SYan, Zheng if (list_empty(&next->upper)) 27563fd0a558SYan, Zheng break; 27573fd0a558SYan, Zheng 27583fd0a558SYan, Zheng edge = list_entry(next->upper.next, 2759a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 27603fd0a558SYan, Zheng edges[index++] = edge; 27613fd0a558SYan, Zheng next = edge->node[UPPER]; 27625d4f98a2SYan Zheng } 27633fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 27643fd0a558SYan, Zheng } 27653fd0a558SYan, Zheng return num_bytes; 27663fd0a558SYan, Zheng } 27673fd0a558SYan, Zheng 27683fd0a558SYan, Zheng static int reserve_metadata_space(struct btrfs_trans_handle *trans, 27693fd0a558SYan, Zheng struct reloc_control *rc, 2770a26195a5SQu Wenruo struct btrfs_backref_node *node) 27713fd0a558SYan, Zheng { 27723fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 2773da17066cSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 27743fd0a558SYan, Zheng u64 num_bytes; 27753fd0a558SYan, Zheng int ret; 27760647bf56SWang Shilong u64 tmp; 27773fd0a558SYan, Zheng 27783fd0a558SYan, Zheng num_bytes = calcu_metadata_size(rc, node, 1) * 2; 27793fd0a558SYan, Zheng 27803fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 27810647bf56SWang Shilong rc->reserved_bytes += num_bytes; 27828ca17f0fSJosef Bacik 27838ca17f0fSJosef Bacik /* 27848ca17f0fSJosef Bacik * We are under a transaction here so we can only do limited flushing. 27858ca17f0fSJosef Bacik * If we get an enospc just kick back -EAGAIN so we know to drop the 27868ca17f0fSJosef Bacik * transaction and try to refill when we can flush all the things. 27878ca17f0fSJosef Bacik */ 27880647bf56SWang Shilong ret = btrfs_block_rsv_refill(root, rc->block_rsv, num_bytes, 27898ca17f0fSJosef Bacik BTRFS_RESERVE_FLUSH_LIMIT); 27903fd0a558SYan, Zheng if (ret) { 2791da17066cSJeff Mahoney tmp = fs_info->nodesize * RELOCATION_RESERVED_NODES; 27920647bf56SWang Shilong while (tmp <= rc->reserved_bytes) 27930647bf56SWang Shilong tmp <<= 1; 27940647bf56SWang Shilong /* 27950647bf56SWang Shilong * only one thread can access block_rsv at this point, 27960647bf56SWang Shilong * so we don't need hold lock to protect block_rsv. 27970647bf56SWang Shilong * we expand more reservation size here to allow enough 279852042d8eSAndrea Gelmini * space for relocation and we will return earlier in 27990647bf56SWang Shilong * enospc case. 28000647bf56SWang Shilong */ 2801da17066cSJeff Mahoney rc->block_rsv->size = tmp + fs_info->nodesize * 28020647bf56SWang Shilong RELOCATION_RESERVED_NODES; 28038ca17f0fSJosef Bacik return -EAGAIN; 28043fd0a558SYan, Zheng } 28053fd0a558SYan, Zheng 28063fd0a558SYan, Zheng return 0; 28073fd0a558SYan, Zheng } 28083fd0a558SYan, Zheng 28095d4f98a2SYan Zheng /* 28105d4f98a2SYan Zheng * relocate a block tree, and then update pointers in upper level 28115d4f98a2SYan Zheng * blocks that reference the block to point to the new location. 28125d4f98a2SYan Zheng * 28135d4f98a2SYan Zheng * if called by link_to_upper, the block has already been relocated. 28145d4f98a2SYan Zheng * in that case this function just updates pointers. 28155d4f98a2SYan Zheng */ 28165d4f98a2SYan Zheng static int do_relocation(struct btrfs_trans_handle *trans, 28173fd0a558SYan, Zheng struct reloc_control *rc, 2818a26195a5SQu Wenruo struct btrfs_backref_node *node, 28195d4f98a2SYan Zheng struct btrfs_key *key, 28205d4f98a2SYan Zheng struct btrfs_path *path, int lowest) 28215d4f98a2SYan Zheng { 28222ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 2823a26195a5SQu Wenruo struct btrfs_backref_node *upper; 2824a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 2825a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 28265d4f98a2SYan Zheng struct btrfs_root *root; 28275d4f98a2SYan Zheng struct extent_buffer *eb; 28285d4f98a2SYan Zheng u32 blocksize; 28295d4f98a2SYan Zheng u64 bytenr; 28305d4f98a2SYan Zheng u64 generation; 28315d4f98a2SYan Zheng int slot; 28325d4f98a2SYan Zheng int ret; 28335d4f98a2SYan Zheng int err = 0; 28345d4f98a2SYan Zheng 28355d4f98a2SYan Zheng BUG_ON(lowest && node->eb); 28365d4f98a2SYan Zheng 28375d4f98a2SYan Zheng path->lowest_level = node->level + 1; 28383fd0a558SYan, Zheng rc->backref_cache.path[node->level] = node; 28395d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) { 2840581c1760SQu Wenruo struct btrfs_key first_key; 284182fa113fSQu Wenruo struct btrfs_ref ref = { 0 }; 2842581c1760SQu Wenruo 28435d4f98a2SYan Zheng cond_resched(); 28445d4f98a2SYan Zheng 28455d4f98a2SYan Zheng upper = edge->node[UPPER]; 2846dc4103f9SWang Shilong root = select_reloc_root(trans, rc, upper, edges); 28473fd0a558SYan, Zheng BUG_ON(!root); 28485d4f98a2SYan Zheng 28493fd0a558SYan, Zheng if (upper->eb && !upper->locked) { 28503fd0a558SYan, Zheng if (!lowest) { 28513fd0a558SYan, Zheng ret = btrfs_bin_search(upper->eb, key, 28523fd0a558SYan, Zheng upper->level, &slot); 2853cbca7d59SFilipe Manana if (ret < 0) { 2854cbca7d59SFilipe Manana err = ret; 2855cbca7d59SFilipe Manana goto next; 2856cbca7d59SFilipe Manana } 28573fd0a558SYan, Zheng BUG_ON(ret); 28583fd0a558SYan, Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 28593fd0a558SYan, Zheng if (node->eb->start == bytenr) 28603fd0a558SYan, Zheng goto next; 28613fd0a558SYan, Zheng } 28625d4f98a2SYan Zheng drop_node_buffer(upper); 28633fd0a558SYan, Zheng } 28645d4f98a2SYan Zheng 28655d4f98a2SYan Zheng if (!upper->eb) { 28665d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 28673561b9dbSLiu Bo if (ret) { 28683561b9dbSLiu Bo if (ret < 0) 28695d4f98a2SYan Zheng err = ret; 28703561b9dbSLiu Bo else 28713561b9dbSLiu Bo err = -ENOENT; 28723561b9dbSLiu Bo 28733561b9dbSLiu Bo btrfs_release_path(path); 28745d4f98a2SYan Zheng break; 28755d4f98a2SYan Zheng } 28765d4f98a2SYan Zheng 28773fd0a558SYan, Zheng if (!upper->eb) { 28783fd0a558SYan, Zheng upper->eb = path->nodes[upper->level]; 28793fd0a558SYan, Zheng path->nodes[upper->level] = NULL; 28803fd0a558SYan, Zheng } else { 28813fd0a558SYan, Zheng BUG_ON(upper->eb != path->nodes[upper->level]); 28823fd0a558SYan, Zheng } 28833fd0a558SYan, Zheng 28843fd0a558SYan, Zheng upper->locked = 1; 28853fd0a558SYan, Zheng path->locks[upper->level] = 0; 28863fd0a558SYan, Zheng 28875d4f98a2SYan Zheng slot = path->slots[upper->level]; 2888b3b4aa74SDavid Sterba btrfs_release_path(path); 28895d4f98a2SYan Zheng } else { 28905d4f98a2SYan Zheng ret = btrfs_bin_search(upper->eb, key, upper->level, 28915d4f98a2SYan Zheng &slot); 2892cbca7d59SFilipe Manana if (ret < 0) { 2893cbca7d59SFilipe Manana err = ret; 2894cbca7d59SFilipe Manana goto next; 2895cbca7d59SFilipe Manana } 28965d4f98a2SYan Zheng BUG_ON(ret); 28975d4f98a2SYan Zheng } 28985d4f98a2SYan Zheng 28995d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 29003fd0a558SYan, Zheng if (lowest) { 29014547f4d8SLiu Bo if (bytenr != node->bytenr) { 29024547f4d8SLiu Bo btrfs_err(root->fs_info, 29034547f4d8SLiu Bo "lowest leaf/node mismatch: bytenr %llu node->bytenr %llu slot %d upper %llu", 29044547f4d8SLiu Bo bytenr, node->bytenr, slot, 29054547f4d8SLiu Bo upper->eb->start); 29064547f4d8SLiu Bo err = -EIO; 29074547f4d8SLiu Bo goto next; 29084547f4d8SLiu Bo } 29095d4f98a2SYan Zheng } else { 29103fd0a558SYan, Zheng if (node->eb->start == bytenr) 29113fd0a558SYan, Zheng goto next; 29125d4f98a2SYan Zheng } 29135d4f98a2SYan Zheng 2914da17066cSJeff Mahoney blocksize = root->fs_info->nodesize; 29155d4f98a2SYan Zheng generation = btrfs_node_ptr_generation(upper->eb, slot); 2916581c1760SQu Wenruo btrfs_node_key_to_cpu(upper->eb, &first_key, slot); 2917581c1760SQu Wenruo eb = read_tree_block(fs_info, bytenr, generation, 2918581c1760SQu Wenruo upper->level - 1, &first_key); 291964c043deSLiu Bo if (IS_ERR(eb)) { 292064c043deSLiu Bo err = PTR_ERR(eb); 292164c043deSLiu Bo goto next; 292264c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 2923416bc658SJosef Bacik free_extent_buffer(eb); 292497d9a8a4STsutomu Itoh err = -EIO; 292597d9a8a4STsutomu Itoh goto next; 292697d9a8a4STsutomu Itoh } 29275d4f98a2SYan Zheng btrfs_tree_lock(eb); 29288bead258SDavid Sterba btrfs_set_lock_blocking_write(eb); 29295d4f98a2SYan Zheng 29305d4f98a2SYan Zheng if (!node->eb) { 29315d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, eb, upper->eb, 29325d4f98a2SYan Zheng slot, &eb); 29333fd0a558SYan, Zheng btrfs_tree_unlock(eb); 29343fd0a558SYan, Zheng free_extent_buffer(eb); 29355d4f98a2SYan Zheng if (ret < 0) { 29365d4f98a2SYan Zheng err = ret; 29373fd0a558SYan, Zheng goto next; 29385d4f98a2SYan Zheng } 29393fd0a558SYan, Zheng BUG_ON(node->eb != eb); 29405d4f98a2SYan Zheng } else { 29415d4f98a2SYan Zheng btrfs_set_node_blockptr(upper->eb, slot, 29425d4f98a2SYan Zheng node->eb->start); 29435d4f98a2SYan Zheng btrfs_set_node_ptr_generation(upper->eb, slot, 29445d4f98a2SYan Zheng trans->transid); 29455d4f98a2SYan Zheng btrfs_mark_buffer_dirty(upper->eb); 29465d4f98a2SYan Zheng 294782fa113fSQu Wenruo btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, 29485d4f98a2SYan Zheng node->eb->start, blocksize, 294982fa113fSQu Wenruo upper->eb->start); 295082fa113fSQu Wenruo ref.real_root = root->root_key.objectid; 295182fa113fSQu Wenruo btrfs_init_tree_ref(&ref, node->level, 295282fa113fSQu Wenruo btrfs_header_owner(upper->eb)); 295382fa113fSQu Wenruo ret = btrfs_inc_extent_ref(trans, &ref); 29545d4f98a2SYan Zheng BUG_ON(ret); 29555d4f98a2SYan Zheng 29565d4f98a2SYan Zheng ret = btrfs_drop_subtree(trans, root, eb, upper->eb); 29575d4f98a2SYan Zheng BUG_ON(ret); 29585d4f98a2SYan Zheng } 29593fd0a558SYan, Zheng next: 29603fd0a558SYan, Zheng if (!upper->pending) 29613fd0a558SYan, Zheng drop_node_buffer(upper); 29623fd0a558SYan, Zheng else 29633fd0a558SYan, Zheng unlock_node_buffer(upper); 29643fd0a558SYan, Zheng if (err) 29653fd0a558SYan, Zheng break; 29665d4f98a2SYan Zheng } 29673fd0a558SYan, Zheng 29683fd0a558SYan, Zheng if (!err && node->pending) { 29693fd0a558SYan, Zheng drop_node_buffer(node); 29703fd0a558SYan, Zheng list_move_tail(&node->list, &rc->backref_cache.changed); 29713fd0a558SYan, Zheng node->pending = 0; 29725d4f98a2SYan Zheng } 29733fd0a558SYan, Zheng 29745d4f98a2SYan Zheng path->lowest_level = 0; 29753fd0a558SYan, Zheng BUG_ON(err == -ENOSPC); 29765d4f98a2SYan Zheng return err; 29775d4f98a2SYan Zheng } 29785d4f98a2SYan Zheng 29795d4f98a2SYan Zheng static int link_to_upper(struct btrfs_trans_handle *trans, 29803fd0a558SYan, Zheng struct reloc_control *rc, 2981a26195a5SQu Wenruo struct btrfs_backref_node *node, 29825d4f98a2SYan Zheng struct btrfs_path *path) 29835d4f98a2SYan Zheng { 29845d4f98a2SYan Zheng struct btrfs_key key; 29855d4f98a2SYan Zheng 29865d4f98a2SYan Zheng btrfs_node_key_to_cpu(node->eb, &key, 0); 29873fd0a558SYan, Zheng return do_relocation(trans, rc, node, &key, path, 0); 29885d4f98a2SYan Zheng } 29895d4f98a2SYan Zheng 29905d4f98a2SYan Zheng static int finish_pending_nodes(struct btrfs_trans_handle *trans, 29913fd0a558SYan, Zheng struct reloc_control *rc, 29923fd0a558SYan, Zheng struct btrfs_path *path, int err) 29935d4f98a2SYan Zheng { 29943fd0a558SYan, Zheng LIST_HEAD(list); 2995a26195a5SQu Wenruo struct btrfs_backref_cache *cache = &rc->backref_cache; 2996a26195a5SQu Wenruo struct btrfs_backref_node *node; 29975d4f98a2SYan Zheng int level; 29985d4f98a2SYan Zheng int ret; 29995d4f98a2SYan Zheng 30005d4f98a2SYan Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 30015d4f98a2SYan Zheng while (!list_empty(&cache->pending[level])) { 30025d4f98a2SYan Zheng node = list_entry(cache->pending[level].next, 3003a26195a5SQu Wenruo struct btrfs_backref_node, list); 30043fd0a558SYan, Zheng list_move_tail(&node->list, &list); 30053fd0a558SYan, Zheng BUG_ON(!node->pending); 30065d4f98a2SYan Zheng 30073fd0a558SYan, Zheng if (!err) { 30083fd0a558SYan, Zheng ret = link_to_upper(trans, rc, node, path); 30095d4f98a2SYan Zheng if (ret < 0) 30105d4f98a2SYan Zheng err = ret; 30115d4f98a2SYan Zheng } 30125d4f98a2SYan Zheng } 30133fd0a558SYan, Zheng list_splice_init(&list, &cache->pending[level]); 30143fd0a558SYan, Zheng } 30155d4f98a2SYan Zheng return err; 30165d4f98a2SYan Zheng } 30175d4f98a2SYan Zheng 30185d4f98a2SYan Zheng /* 30195d4f98a2SYan Zheng * mark a block and all blocks directly/indirectly reference the block 30205d4f98a2SYan Zheng * as processed. 30215d4f98a2SYan Zheng */ 30225d4f98a2SYan Zheng static void update_processed_blocks(struct reloc_control *rc, 3023a26195a5SQu Wenruo struct btrfs_backref_node *node) 30245d4f98a2SYan Zheng { 3025a26195a5SQu Wenruo struct btrfs_backref_node *next = node; 3026a26195a5SQu Wenruo struct btrfs_backref_edge *edge; 3027a26195a5SQu Wenruo struct btrfs_backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 30285d4f98a2SYan Zheng int index = 0; 30295d4f98a2SYan Zheng 30305d4f98a2SYan Zheng while (next) { 30315d4f98a2SYan Zheng cond_resched(); 30325d4f98a2SYan Zheng while (1) { 30335d4f98a2SYan Zheng if (next->processed) 30345d4f98a2SYan Zheng break; 30355d4f98a2SYan Zheng 30369569cc20SQu Wenruo mark_block_processed(rc, next); 30375d4f98a2SYan Zheng 30385d4f98a2SYan Zheng if (list_empty(&next->upper)) 30395d4f98a2SYan Zheng break; 30405d4f98a2SYan Zheng 30415d4f98a2SYan Zheng edge = list_entry(next->upper.next, 3042a26195a5SQu Wenruo struct btrfs_backref_edge, list[LOWER]); 30435d4f98a2SYan Zheng edges[index++] = edge; 30445d4f98a2SYan Zheng next = edge->node[UPPER]; 30455d4f98a2SYan Zheng } 30465d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 30475d4f98a2SYan Zheng } 30485d4f98a2SYan Zheng } 30495d4f98a2SYan Zheng 30507476dfdaSDavid Sterba static int tree_block_processed(u64 bytenr, struct reloc_control *rc) 30515d4f98a2SYan Zheng { 3052da17066cSJeff Mahoney u32 blocksize = rc->extent_root->fs_info->nodesize; 30537476dfdaSDavid Sterba 30545d4f98a2SYan Zheng if (test_range_bit(&rc->processed_blocks, bytenr, 30559655d298SChris Mason bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) 30565d4f98a2SYan Zheng return 1; 30575d4f98a2SYan Zheng return 0; 30585d4f98a2SYan Zheng } 30595d4f98a2SYan Zheng 30602ff7e61eSJeff Mahoney static int get_tree_block_key(struct btrfs_fs_info *fs_info, 30615d4f98a2SYan Zheng struct tree_block *block) 30625d4f98a2SYan Zheng { 30635d4f98a2SYan Zheng struct extent_buffer *eb; 30645d4f98a2SYan Zheng 3065581c1760SQu Wenruo eb = read_tree_block(fs_info, block->bytenr, block->key.offset, 3066581c1760SQu Wenruo block->level, NULL); 306764c043deSLiu Bo if (IS_ERR(eb)) { 306864c043deSLiu Bo return PTR_ERR(eb); 306964c043deSLiu Bo } else if (!extent_buffer_uptodate(eb)) { 3070416bc658SJosef Bacik free_extent_buffer(eb); 3071416bc658SJosef Bacik return -EIO; 3072416bc658SJosef Bacik } 30735d4f98a2SYan Zheng if (block->level == 0) 30745d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &block->key, 0); 30755d4f98a2SYan Zheng else 30765d4f98a2SYan Zheng btrfs_node_key_to_cpu(eb, &block->key, 0); 30775d4f98a2SYan Zheng free_extent_buffer(eb); 30785d4f98a2SYan Zheng block->key_ready = 1; 30795d4f98a2SYan Zheng return 0; 30805d4f98a2SYan Zheng } 30815d4f98a2SYan Zheng 30825d4f98a2SYan Zheng /* 30835d4f98a2SYan Zheng * helper function to relocate a tree block 30845d4f98a2SYan Zheng */ 30855d4f98a2SYan Zheng static int relocate_tree_block(struct btrfs_trans_handle *trans, 30865d4f98a2SYan Zheng struct reloc_control *rc, 3087a26195a5SQu Wenruo struct btrfs_backref_node *node, 30885d4f98a2SYan Zheng struct btrfs_key *key, 30895d4f98a2SYan Zheng struct btrfs_path *path) 30905d4f98a2SYan Zheng { 30915d4f98a2SYan Zheng struct btrfs_root *root; 30923fd0a558SYan, Zheng int ret = 0; 30935d4f98a2SYan Zheng 30943fd0a558SYan, Zheng if (!node) 30955d4f98a2SYan Zheng return 0; 30963fd0a558SYan, Zheng 30975f6b2e5cSJosef Bacik /* 30985f6b2e5cSJosef Bacik * If we fail here we want to drop our backref_node because we are going 30995f6b2e5cSJosef Bacik * to start over and regenerate the tree for it. 31005f6b2e5cSJosef Bacik */ 31015f6b2e5cSJosef Bacik ret = reserve_metadata_space(trans, rc, node); 31025f6b2e5cSJosef Bacik if (ret) 31035f6b2e5cSJosef Bacik goto out; 31045f6b2e5cSJosef Bacik 31053fd0a558SYan, Zheng BUG_ON(node->processed); 3106147d256eSZhaolei root = select_one_root(node); 31073fd0a558SYan, Zheng if (root == ERR_PTR(-ENOENT)) { 31083fd0a558SYan, Zheng update_processed_blocks(rc, node); 31093fd0a558SYan, Zheng goto out; 31105d4f98a2SYan Zheng } 31115d4f98a2SYan Zheng 31123fd0a558SYan, Zheng if (root) { 311327cdeb70SMiao Xie if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) { 31143fd0a558SYan, Zheng BUG_ON(node->new_bytenr); 31153fd0a558SYan, Zheng BUG_ON(!list_empty(&node->list)); 31163fd0a558SYan, Zheng btrfs_record_root_in_trans(trans, root); 31173fd0a558SYan, Zheng root = root->reloc_root; 31183fd0a558SYan, Zheng node->new_bytenr = root->node->start; 311900246528SJosef Bacik btrfs_put_root(node->root); 312000246528SJosef Bacik node->root = btrfs_grab_root(root); 31210b530bc5SJosef Bacik ASSERT(node->root); 31223fd0a558SYan, Zheng list_add_tail(&node->list, &rc->backref_cache.changed); 31233fd0a558SYan, Zheng } else { 31245d4f98a2SYan Zheng path->lowest_level = node->level; 31255d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 3126b3b4aa74SDavid Sterba btrfs_release_path(path); 31273fd0a558SYan, Zheng if (ret > 0) 31285d4f98a2SYan Zheng ret = 0; 31293fd0a558SYan, Zheng } 31303fd0a558SYan, Zheng if (!ret) 31313fd0a558SYan, Zheng update_processed_blocks(rc, node); 31323fd0a558SYan, Zheng } else { 31333fd0a558SYan, Zheng ret = do_relocation(trans, rc, node, key, path, 1); 31343fd0a558SYan, Zheng } 31355d4f98a2SYan Zheng out: 31360647bf56SWang Shilong if (ret || node->level == 0 || node->cowonly) 31373fd0a558SYan, Zheng remove_backref_node(&rc->backref_cache, node); 31385d4f98a2SYan Zheng return ret; 31395d4f98a2SYan Zheng } 31405d4f98a2SYan Zheng 31415d4f98a2SYan Zheng /* 31425d4f98a2SYan Zheng * relocate a list of blocks 31435d4f98a2SYan Zheng */ 31445d4f98a2SYan Zheng static noinline_for_stack 31455d4f98a2SYan Zheng int relocate_tree_blocks(struct btrfs_trans_handle *trans, 31465d4f98a2SYan Zheng struct reloc_control *rc, struct rb_root *blocks) 31475d4f98a2SYan Zheng { 31482ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 3149a26195a5SQu Wenruo struct btrfs_backref_node *node; 31505d4f98a2SYan Zheng struct btrfs_path *path; 31515d4f98a2SYan Zheng struct tree_block *block; 315298ff7b94SQu Wenruo struct tree_block *next; 31535d4f98a2SYan Zheng int ret; 31545d4f98a2SYan Zheng int err = 0; 31555d4f98a2SYan Zheng 31565d4f98a2SYan Zheng path = btrfs_alloc_path(); 3157e1a12670SLiu Bo if (!path) { 3158e1a12670SLiu Bo err = -ENOMEM; 315934c2b290SDavid Sterba goto out_free_blocks; 3160e1a12670SLiu Bo } 31615d4f98a2SYan Zheng 316298ff7b94SQu Wenruo /* Kick in readahead for tree blocks with missing keys */ 316398ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 31645d4f98a2SYan Zheng if (!block->key_ready) 31652ff7e61eSJeff Mahoney readahead_tree_block(fs_info, block->bytenr); 31665d4f98a2SYan Zheng } 31675d4f98a2SYan Zheng 316898ff7b94SQu Wenruo /* Get first keys */ 316998ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 317034c2b290SDavid Sterba if (!block->key_ready) { 31712ff7e61eSJeff Mahoney err = get_tree_block_key(fs_info, block); 317234c2b290SDavid Sterba if (err) 317334c2b290SDavid Sterba goto out_free_path; 317434c2b290SDavid Sterba } 31755d4f98a2SYan Zheng } 31765d4f98a2SYan Zheng 317798ff7b94SQu Wenruo /* Do tree relocation */ 317898ff7b94SQu Wenruo rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) { 31793fd0a558SYan, Zheng node = build_backref_tree(rc, &block->key, 31805d4f98a2SYan Zheng block->level, block->bytenr); 31815d4f98a2SYan Zheng if (IS_ERR(node)) { 31825d4f98a2SYan Zheng err = PTR_ERR(node); 31835d4f98a2SYan Zheng goto out; 31845d4f98a2SYan Zheng } 31855d4f98a2SYan Zheng 31865d4f98a2SYan Zheng ret = relocate_tree_block(trans, rc, node, &block->key, 31875d4f98a2SYan Zheng path); 31885d4f98a2SYan Zheng if (ret < 0) { 31895d4f98a2SYan Zheng err = ret; 319050dbbb71SJosef Bacik break; 31915d4f98a2SYan Zheng } 31925d4f98a2SYan Zheng } 31935d4f98a2SYan Zheng out: 31943fd0a558SYan, Zheng err = finish_pending_nodes(trans, rc, path, err); 31955d4f98a2SYan Zheng 319634c2b290SDavid Sterba out_free_path: 31975d4f98a2SYan Zheng btrfs_free_path(path); 319834c2b290SDavid Sterba out_free_blocks: 3199e1a12670SLiu Bo free_block_list(blocks); 32005d4f98a2SYan Zheng return err; 32015d4f98a2SYan Zheng } 32025d4f98a2SYan Zheng 32035d4f98a2SYan Zheng static noinline_for_stack 3204efa56464SYan, Zheng int prealloc_file_extent_cluster(struct inode *inode, 3205efa56464SYan, Zheng struct file_extent_cluster *cluster) 3206efa56464SYan, Zheng { 3207efa56464SYan, Zheng u64 alloc_hint = 0; 3208efa56464SYan, Zheng u64 start; 3209efa56464SYan, Zheng u64 end; 3210efa56464SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 3211efa56464SYan, Zheng u64 num_bytes; 3212efa56464SYan, Zheng int nr = 0; 3213efa56464SYan, Zheng int ret = 0; 3214dcb40c19SWang Xiaoguang u64 prealloc_start = cluster->start - offset; 3215dcb40c19SWang Xiaoguang u64 prealloc_end = cluster->end - offset; 321618513091SWang Xiaoguang u64 cur_offset; 3217364ecf36SQu Wenruo struct extent_changeset *data_reserved = NULL; 3218efa56464SYan, Zheng 3219efa56464SYan, Zheng BUG_ON(cluster->start != cluster->boundary[0]); 32205955102cSAl Viro inode_lock(inode); 3221efa56464SYan, Zheng 3222364ecf36SQu Wenruo ret = btrfs_check_data_free_space(inode, &data_reserved, prealloc_start, 3223dcb40c19SWang Xiaoguang prealloc_end + 1 - prealloc_start); 3224efa56464SYan, Zheng if (ret) 3225efa56464SYan, Zheng goto out; 3226efa56464SYan, Zheng 322718513091SWang Xiaoguang cur_offset = prealloc_start; 3228efa56464SYan, Zheng while (nr < cluster->nr) { 3229efa56464SYan, Zheng start = cluster->boundary[nr] - offset; 3230efa56464SYan, Zheng if (nr + 1 < cluster->nr) 3231efa56464SYan, Zheng end = cluster->boundary[nr + 1] - 1 - offset; 3232efa56464SYan, Zheng else 3233efa56464SYan, Zheng end = cluster->end - offset; 3234efa56464SYan, Zheng 3235d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 3236efa56464SYan, Zheng num_bytes = end + 1 - start; 323718513091SWang Xiaoguang if (cur_offset < start) 3238bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3239bc42bda2SQu Wenruo cur_offset, start - cur_offset); 3240efa56464SYan, Zheng ret = btrfs_prealloc_file_range(inode, 0, start, 3241efa56464SYan, Zheng num_bytes, num_bytes, 3242efa56464SYan, Zheng end + 1, &alloc_hint); 324318513091SWang Xiaoguang cur_offset = end + 1; 3244d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 3245efa56464SYan, Zheng if (ret) 3246efa56464SYan, Zheng break; 3247efa56464SYan, Zheng nr++; 3248efa56464SYan, Zheng } 324918513091SWang Xiaoguang if (cur_offset < prealloc_end) 3250bc42bda2SQu Wenruo btrfs_free_reserved_data_space(inode, data_reserved, 3251bc42bda2SQu Wenruo cur_offset, prealloc_end + 1 - cur_offset); 3252efa56464SYan, Zheng out: 32535955102cSAl Viro inode_unlock(inode); 3254364ecf36SQu Wenruo extent_changeset_free(data_reserved); 3255efa56464SYan, Zheng return ret; 3256efa56464SYan, Zheng } 3257efa56464SYan, Zheng 3258efa56464SYan, Zheng static noinline_for_stack 32590257bb82SYan, Zheng int setup_extent_mapping(struct inode *inode, u64 start, u64 end, 32600257bb82SYan, Zheng u64 block_start) 32615d4f98a2SYan Zheng { 32625d4f98a2SYan Zheng struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 32635d4f98a2SYan Zheng struct extent_map *em; 32640257bb82SYan, Zheng int ret = 0; 32655d4f98a2SYan Zheng 3266172ddd60SDavid Sterba em = alloc_extent_map(); 32670257bb82SYan, Zheng if (!em) 32680257bb82SYan, Zheng return -ENOMEM; 32690257bb82SYan, Zheng 32705d4f98a2SYan Zheng em->start = start; 32710257bb82SYan, Zheng em->len = end + 1 - start; 32720257bb82SYan, Zheng em->block_len = em->len; 32730257bb82SYan, Zheng em->block_start = block_start; 32745d4f98a2SYan Zheng set_bit(EXTENT_FLAG_PINNED, &em->flags); 32755d4f98a2SYan Zheng 3276d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, start, end); 32775d4f98a2SYan Zheng while (1) { 3278890871beSChris Mason write_lock(&em_tree->lock); 327909a2a8f9SJosef Bacik ret = add_extent_mapping(em_tree, em, 0); 3280890871beSChris Mason write_unlock(&em_tree->lock); 32815d4f98a2SYan Zheng if (ret != -EEXIST) { 32825d4f98a2SYan Zheng free_extent_map(em); 32835d4f98a2SYan Zheng break; 32845d4f98a2SYan Zheng } 3285dcdbc059SNikolay Borisov btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); 32865d4f98a2SYan Zheng } 3287d0082371SJeff Mahoney unlock_extent(&BTRFS_I(inode)->io_tree, start, end); 32880257bb82SYan, Zheng return ret; 32890257bb82SYan, Zheng } 32905d4f98a2SYan Zheng 3291726a3421SQu Wenruo /* 3292726a3421SQu Wenruo * Allow error injection to test balance cancellation 3293726a3421SQu Wenruo */ 3294726a3421SQu Wenruo int btrfs_should_cancel_balance(struct btrfs_fs_info *fs_info) 3295726a3421SQu Wenruo { 3296726a3421SQu Wenruo return atomic_read(&fs_info->balance_cancel_req); 3297726a3421SQu Wenruo } 3298726a3421SQu Wenruo ALLOW_ERROR_INJECTION(btrfs_should_cancel_balance, TRUE); 3299726a3421SQu Wenruo 33000257bb82SYan, Zheng static int relocate_file_extent_cluster(struct inode *inode, 33010257bb82SYan, Zheng struct file_extent_cluster *cluster) 33020257bb82SYan, Zheng { 33032ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 33040257bb82SYan, Zheng u64 page_start; 33050257bb82SYan, Zheng u64 page_end; 33060257bb82SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 33070257bb82SYan, Zheng unsigned long index; 33080257bb82SYan, Zheng unsigned long last_index; 33090257bb82SYan, Zheng struct page *page; 33100257bb82SYan, Zheng struct file_ra_state *ra; 33113b16a4e3SJosef Bacik gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); 33120257bb82SYan, Zheng int nr = 0; 33130257bb82SYan, Zheng int ret = 0; 33140257bb82SYan, Zheng 33150257bb82SYan, Zheng if (!cluster->nr) 33160257bb82SYan, Zheng return 0; 33170257bb82SYan, Zheng 33180257bb82SYan, Zheng ra = kzalloc(sizeof(*ra), GFP_NOFS); 33190257bb82SYan, Zheng if (!ra) 33200257bb82SYan, Zheng return -ENOMEM; 33210257bb82SYan, Zheng 3322efa56464SYan, Zheng ret = prealloc_file_extent_cluster(inode, cluster); 33230257bb82SYan, Zheng if (ret) 3324efa56464SYan, Zheng goto out; 33250257bb82SYan, Zheng 33260257bb82SYan, Zheng file_ra_state_init(ra, inode->i_mapping); 33270257bb82SYan, Zheng 3328efa56464SYan, Zheng ret = setup_extent_mapping(inode, cluster->start - offset, 3329efa56464SYan, Zheng cluster->end - offset, cluster->start); 3330efa56464SYan, Zheng if (ret) 3331efa56464SYan, Zheng goto out; 3332efa56464SYan, Zheng 333309cbfeafSKirill A. Shutemov index = (cluster->start - offset) >> PAGE_SHIFT; 333409cbfeafSKirill A. Shutemov last_index = (cluster->end - offset) >> PAGE_SHIFT; 33350257bb82SYan, Zheng while (index <= last_index) { 33369f3db423SNikolay Borisov ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), 33379f3db423SNikolay Borisov PAGE_SIZE); 3338efa56464SYan, Zheng if (ret) 3339efa56464SYan, Zheng goto out; 3340efa56464SYan, Zheng 33410257bb82SYan, Zheng page = find_lock_page(inode->i_mapping, index); 33420257bb82SYan, Zheng if (!page) { 33430257bb82SYan, Zheng page_cache_sync_readahead(inode->i_mapping, 33440257bb82SYan, Zheng ra, NULL, index, 33450257bb82SYan, Zheng last_index + 1 - index); 3346a94733d0SJosef Bacik page = find_or_create_page(inode->i_mapping, index, 33473b16a4e3SJosef Bacik mask); 33480257bb82SYan, Zheng if (!page) { 3349691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 335043b18595SQu Wenruo PAGE_SIZE, true); 335144db1216SFilipe Manana btrfs_delalloc_release_extents(BTRFS_I(inode), 33528702ba93SQu Wenruo PAGE_SIZE); 33530257bb82SYan, Zheng ret = -ENOMEM; 3354efa56464SYan, Zheng goto out; 33550257bb82SYan, Zheng } 33560257bb82SYan, Zheng } 33570257bb82SYan, Zheng 33580257bb82SYan, Zheng if (PageReadahead(page)) { 33590257bb82SYan, Zheng page_cache_async_readahead(inode->i_mapping, 33600257bb82SYan, Zheng ra, NULL, page, index, 33610257bb82SYan, Zheng last_index + 1 - index); 33620257bb82SYan, Zheng } 33630257bb82SYan, Zheng 33640257bb82SYan, Zheng if (!PageUptodate(page)) { 33650257bb82SYan, Zheng btrfs_readpage(NULL, page); 33660257bb82SYan, Zheng lock_page(page); 33670257bb82SYan, Zheng if (!PageUptodate(page)) { 33680257bb82SYan, Zheng unlock_page(page); 336909cbfeafSKirill A. Shutemov put_page(page); 3370691fa059SNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 337143b18595SQu Wenruo PAGE_SIZE, true); 33728b62f87bSJosef Bacik btrfs_delalloc_release_extents(BTRFS_I(inode), 33738702ba93SQu Wenruo PAGE_SIZE); 33740257bb82SYan, Zheng ret = -EIO; 3375efa56464SYan, Zheng goto out; 33760257bb82SYan, Zheng } 33770257bb82SYan, Zheng } 33780257bb82SYan, Zheng 33794eee4fa4SMiao Xie page_start = page_offset(page); 338009cbfeafSKirill A. Shutemov page_end = page_start + PAGE_SIZE - 1; 33810257bb82SYan, Zheng 3382d0082371SJeff Mahoney lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end); 33830257bb82SYan, Zheng 33840257bb82SYan, Zheng set_page_extent_mapped(page); 33850257bb82SYan, Zheng 33860257bb82SYan, Zheng if (nr < cluster->nr && 33870257bb82SYan, Zheng page_start + offset == cluster->boundary[nr]) { 33880257bb82SYan, Zheng set_extent_bits(&BTRFS_I(inode)->io_tree, 33890257bb82SYan, Zheng page_start, page_end, 3390ceeb0ae7SDavid Sterba EXTENT_BOUNDARY); 33910257bb82SYan, Zheng nr++; 33920257bb82SYan, Zheng } 33930257bb82SYan, Zheng 3394765f3cebSNikolay Borisov ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, 3395330a5827SNikolay Borisov NULL); 3396765f3cebSNikolay Borisov if (ret) { 3397765f3cebSNikolay Borisov unlock_page(page); 3398765f3cebSNikolay Borisov put_page(page); 3399765f3cebSNikolay Borisov btrfs_delalloc_release_metadata(BTRFS_I(inode), 340043b18595SQu Wenruo PAGE_SIZE, true); 3401765f3cebSNikolay Borisov btrfs_delalloc_release_extents(BTRFS_I(inode), 34028702ba93SQu Wenruo PAGE_SIZE); 3403765f3cebSNikolay Borisov 3404765f3cebSNikolay Borisov clear_extent_bits(&BTRFS_I(inode)->io_tree, 3405765f3cebSNikolay Borisov page_start, page_end, 3406765f3cebSNikolay Borisov EXTENT_LOCKED | EXTENT_BOUNDARY); 3407765f3cebSNikolay Borisov goto out; 3408765f3cebSNikolay Borisov 3409765f3cebSNikolay Borisov } 34100257bb82SYan, Zheng set_page_dirty(page); 34110257bb82SYan, Zheng 34120257bb82SYan, Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 3413d0082371SJeff Mahoney page_start, page_end); 34140257bb82SYan, Zheng unlock_page(page); 341509cbfeafSKirill A. Shutemov put_page(page); 34160257bb82SYan, Zheng 34170257bb82SYan, Zheng index++; 34188702ba93SQu Wenruo btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE); 3419efa56464SYan, Zheng balance_dirty_pages_ratelimited(inode->i_mapping); 34202ff7e61eSJeff Mahoney btrfs_throttle(fs_info); 34217f913c7cSQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 34227f913c7cSQu Wenruo ret = -ECANCELED; 34237f913c7cSQu Wenruo goto out; 34247f913c7cSQu Wenruo } 34250257bb82SYan, Zheng } 34260257bb82SYan, Zheng WARN_ON(nr != cluster->nr); 3427efa56464SYan, Zheng out: 34280257bb82SYan, Zheng kfree(ra); 34290257bb82SYan, Zheng return ret; 34300257bb82SYan, Zheng } 34310257bb82SYan, Zheng 34320257bb82SYan, Zheng static noinline_for_stack 34330257bb82SYan, Zheng int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, 34340257bb82SYan, Zheng struct file_extent_cluster *cluster) 34350257bb82SYan, Zheng { 34360257bb82SYan, Zheng int ret; 34370257bb82SYan, Zheng 34380257bb82SYan, Zheng if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) { 34390257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 34400257bb82SYan, Zheng if (ret) 34410257bb82SYan, Zheng return ret; 34420257bb82SYan, Zheng cluster->nr = 0; 34430257bb82SYan, Zheng } 34440257bb82SYan, Zheng 34450257bb82SYan, Zheng if (!cluster->nr) 34460257bb82SYan, Zheng cluster->start = extent_key->objectid; 34470257bb82SYan, Zheng else 34480257bb82SYan, Zheng BUG_ON(cluster->nr >= MAX_EXTENTS); 34490257bb82SYan, Zheng cluster->end = extent_key->objectid + extent_key->offset - 1; 34500257bb82SYan, Zheng cluster->boundary[cluster->nr] = extent_key->objectid; 34510257bb82SYan, Zheng cluster->nr++; 34520257bb82SYan, Zheng 34530257bb82SYan, Zheng if (cluster->nr >= MAX_EXTENTS) { 34540257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 34550257bb82SYan, Zheng if (ret) 34560257bb82SYan, Zheng return ret; 34570257bb82SYan, Zheng cluster->nr = 0; 34580257bb82SYan, Zheng } 34590257bb82SYan, Zheng return 0; 34605d4f98a2SYan Zheng } 34615d4f98a2SYan Zheng 34625d4f98a2SYan Zheng /* 34635d4f98a2SYan Zheng * helper to add a tree block to the list. 34645d4f98a2SYan Zheng * the major work is getting the generation and level of the block 34655d4f98a2SYan Zheng */ 34665d4f98a2SYan Zheng static int add_tree_block(struct reloc_control *rc, 34675d4f98a2SYan Zheng struct btrfs_key *extent_key, 34685d4f98a2SYan Zheng struct btrfs_path *path, 34695d4f98a2SYan Zheng struct rb_root *blocks) 34705d4f98a2SYan Zheng { 34715d4f98a2SYan Zheng struct extent_buffer *eb; 34725d4f98a2SYan Zheng struct btrfs_extent_item *ei; 34735d4f98a2SYan Zheng struct btrfs_tree_block_info *bi; 34745d4f98a2SYan Zheng struct tree_block *block; 34755d4f98a2SYan Zheng struct rb_node *rb_node; 34765d4f98a2SYan Zheng u32 item_size; 34775d4f98a2SYan Zheng int level = -1; 34787fdf4b60SWang Shilong u64 generation; 34795d4f98a2SYan Zheng 34805d4f98a2SYan Zheng eb = path->nodes[0]; 34815d4f98a2SYan Zheng item_size = btrfs_item_size_nr(eb, path->slots[0]); 34825d4f98a2SYan Zheng 34833173a18fSJosef Bacik if (extent_key->type == BTRFS_METADATA_ITEM_KEY || 34843173a18fSJosef Bacik item_size >= sizeof(*ei) + sizeof(*bi)) { 34855d4f98a2SYan Zheng ei = btrfs_item_ptr(eb, path->slots[0], 34865d4f98a2SYan Zheng struct btrfs_extent_item); 34873173a18fSJosef Bacik if (extent_key->type == BTRFS_EXTENT_ITEM_KEY) { 34885d4f98a2SYan Zheng bi = (struct btrfs_tree_block_info *)(ei + 1); 34895d4f98a2SYan Zheng level = btrfs_tree_block_level(eb, bi); 34905d4f98a2SYan Zheng } else { 34913173a18fSJosef Bacik level = (int)extent_key->offset; 34923173a18fSJosef Bacik } 34933173a18fSJosef Bacik generation = btrfs_extent_generation(eb, ei); 34946d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3495ba3c2b19SNikolay Borisov btrfs_print_v0_err(eb->fs_info); 3496ba3c2b19SNikolay Borisov btrfs_handle_fs_error(eb->fs_info, -EINVAL, NULL); 3497ba3c2b19SNikolay Borisov return -EINVAL; 34983173a18fSJosef Bacik } else { 34995d4f98a2SYan Zheng BUG(); 35005d4f98a2SYan Zheng } 35015d4f98a2SYan Zheng 3502b3b4aa74SDavid Sterba btrfs_release_path(path); 35035d4f98a2SYan Zheng 35045d4f98a2SYan Zheng BUG_ON(level == -1); 35055d4f98a2SYan Zheng 35065d4f98a2SYan Zheng block = kmalloc(sizeof(*block), GFP_NOFS); 35075d4f98a2SYan Zheng if (!block) 35085d4f98a2SYan Zheng return -ENOMEM; 35095d4f98a2SYan Zheng 35105d4f98a2SYan Zheng block->bytenr = extent_key->objectid; 3511da17066cSJeff Mahoney block->key.objectid = rc->extent_root->fs_info->nodesize; 35125d4f98a2SYan Zheng block->key.offset = generation; 35135d4f98a2SYan Zheng block->level = level; 35145d4f98a2SYan Zheng block->key_ready = 0; 35155d4f98a2SYan Zheng 3516e9a28dc5SQu Wenruo rb_node = rb_simple_insert(blocks, block->bytenr, &block->rb_node); 351743c04fb1SJeff Mahoney if (rb_node) 351843c04fb1SJeff Mahoney backref_tree_panic(rb_node, -EEXIST, block->bytenr); 35195d4f98a2SYan Zheng 35205d4f98a2SYan Zheng return 0; 35215d4f98a2SYan Zheng } 35225d4f98a2SYan Zheng 35235d4f98a2SYan Zheng /* 35245d4f98a2SYan Zheng * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY 35255d4f98a2SYan Zheng */ 35265d4f98a2SYan Zheng static int __add_tree_block(struct reloc_control *rc, 35275d4f98a2SYan Zheng u64 bytenr, u32 blocksize, 35285d4f98a2SYan Zheng struct rb_root *blocks) 35295d4f98a2SYan Zheng { 35300b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 35315d4f98a2SYan Zheng struct btrfs_path *path; 35325d4f98a2SYan Zheng struct btrfs_key key; 35335d4f98a2SYan Zheng int ret; 35340b246afaSJeff Mahoney bool skinny = btrfs_fs_incompat(fs_info, SKINNY_METADATA); 35355d4f98a2SYan Zheng 35367476dfdaSDavid Sterba if (tree_block_processed(bytenr, rc)) 35375d4f98a2SYan Zheng return 0; 35385d4f98a2SYan Zheng 3539e9a28dc5SQu Wenruo if (rb_simple_search(blocks, bytenr)) 35405d4f98a2SYan Zheng return 0; 35415d4f98a2SYan Zheng 35425d4f98a2SYan Zheng path = btrfs_alloc_path(); 35435d4f98a2SYan Zheng if (!path) 35445d4f98a2SYan Zheng return -ENOMEM; 3545aee68ee5SJosef Bacik again: 35465d4f98a2SYan Zheng key.objectid = bytenr; 3547aee68ee5SJosef Bacik if (skinny) { 3548aee68ee5SJosef Bacik key.type = BTRFS_METADATA_ITEM_KEY; 3549aee68ee5SJosef Bacik key.offset = (u64)-1; 3550aee68ee5SJosef Bacik } else { 35515d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 35525d4f98a2SYan Zheng key.offset = blocksize; 3553aee68ee5SJosef Bacik } 35545d4f98a2SYan Zheng 35555d4f98a2SYan Zheng path->search_commit_root = 1; 35565d4f98a2SYan Zheng path->skip_locking = 1; 35575d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); 35585d4f98a2SYan Zheng if (ret < 0) 35595d4f98a2SYan Zheng goto out; 35605d4f98a2SYan Zheng 3561aee68ee5SJosef Bacik if (ret > 0 && skinny) { 3562aee68ee5SJosef Bacik if (path->slots[0]) { 3563aee68ee5SJosef Bacik path->slots[0]--; 3564aee68ee5SJosef Bacik btrfs_item_key_to_cpu(path->nodes[0], &key, 3565aee68ee5SJosef Bacik path->slots[0]); 35663173a18fSJosef Bacik if (key.objectid == bytenr && 3567aee68ee5SJosef Bacik (key.type == BTRFS_METADATA_ITEM_KEY || 3568aee68ee5SJosef Bacik (key.type == BTRFS_EXTENT_ITEM_KEY && 3569aee68ee5SJosef Bacik key.offset == blocksize))) 35703173a18fSJosef Bacik ret = 0; 35713173a18fSJosef Bacik } 3572aee68ee5SJosef Bacik 3573aee68ee5SJosef Bacik if (ret) { 3574aee68ee5SJosef Bacik skinny = false; 3575aee68ee5SJosef Bacik btrfs_release_path(path); 3576aee68ee5SJosef Bacik goto again; 3577aee68ee5SJosef Bacik } 3578aee68ee5SJosef Bacik } 3579cdccee99SLiu Bo if (ret) { 3580cdccee99SLiu Bo ASSERT(ret == 1); 3581cdccee99SLiu Bo btrfs_print_leaf(path->nodes[0]); 3582cdccee99SLiu Bo btrfs_err(fs_info, 3583cdccee99SLiu Bo "tree block extent item (%llu) is not found in extent tree", 3584cdccee99SLiu Bo bytenr); 3585cdccee99SLiu Bo WARN_ON(1); 3586cdccee99SLiu Bo ret = -EINVAL; 3587cdccee99SLiu Bo goto out; 3588cdccee99SLiu Bo } 35893173a18fSJosef Bacik 35905d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, blocks); 35915d4f98a2SYan Zheng out: 35925d4f98a2SYan Zheng btrfs_free_path(path); 35935d4f98a2SYan Zheng return ret; 35945d4f98a2SYan Zheng } 35955d4f98a2SYan Zheng 35960af3d00bSJosef Bacik static int delete_block_group_cache(struct btrfs_fs_info *fs_info, 359732da5386SDavid Sterba struct btrfs_block_group *block_group, 35981bbc621eSChris Mason struct inode *inode, 35991bbc621eSChris Mason u64 ino) 36000af3d00bSJosef Bacik { 36010af3d00bSJosef Bacik struct btrfs_key key; 36020af3d00bSJosef Bacik struct btrfs_root *root = fs_info->tree_root; 36030af3d00bSJosef Bacik struct btrfs_trans_handle *trans; 36040af3d00bSJosef Bacik int ret = 0; 36050af3d00bSJosef Bacik 36060af3d00bSJosef Bacik if (inode) 36070af3d00bSJosef Bacik goto truncate; 36080af3d00bSJosef Bacik 36090af3d00bSJosef Bacik key.objectid = ino; 36100af3d00bSJosef Bacik key.type = BTRFS_INODE_ITEM_KEY; 36110af3d00bSJosef Bacik key.offset = 0; 36120af3d00bSJosef Bacik 36134c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 36142e19f1f9SAl Viro if (IS_ERR(inode)) 36150af3d00bSJosef Bacik return -ENOENT; 36160af3d00bSJosef Bacik 36170af3d00bSJosef Bacik truncate: 36182ff7e61eSJeff Mahoney ret = btrfs_check_trunc_cache_free_space(fs_info, 36197b61cd92SMiao Xie &fs_info->global_block_rsv); 36207b61cd92SMiao Xie if (ret) 36217b61cd92SMiao Xie goto out; 36227b61cd92SMiao Xie 36237a7eaa40SJosef Bacik trans = btrfs_join_transaction(root); 36240af3d00bSJosef Bacik if (IS_ERR(trans)) { 36253612b495STsutomu Itoh ret = PTR_ERR(trans); 36260af3d00bSJosef Bacik goto out; 36270af3d00bSJosef Bacik } 36280af3d00bSJosef Bacik 362977ab86bfSJeff Mahoney ret = btrfs_truncate_free_space_cache(trans, block_group, inode); 36300af3d00bSJosef Bacik 36313a45bb20SJeff Mahoney btrfs_end_transaction(trans); 36322ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 36330af3d00bSJosef Bacik out: 36340af3d00bSJosef Bacik iput(inode); 36350af3d00bSJosef Bacik return ret; 36360af3d00bSJosef Bacik } 36370af3d00bSJosef Bacik 36385d4f98a2SYan Zheng /* 363919b546d7SQu Wenruo * Locate the free space cache EXTENT_DATA in root tree leaf and delete the 364019b546d7SQu Wenruo * cache inode, to avoid free space cache data extent blocking data relocation. 36415d4f98a2SYan Zheng */ 364219b546d7SQu Wenruo static int delete_v1_space_cache(struct extent_buffer *leaf, 364319b546d7SQu Wenruo struct btrfs_block_group *block_group, 364419b546d7SQu Wenruo u64 data_bytenr) 36455d4f98a2SYan Zheng { 364619b546d7SQu Wenruo u64 space_cache_ino; 364719b546d7SQu Wenruo struct btrfs_file_extent_item *ei; 36485d4f98a2SYan Zheng struct btrfs_key key; 364919b546d7SQu Wenruo bool found = false; 365019b546d7SQu Wenruo int i; 36515d4f98a2SYan Zheng int ret; 36525d4f98a2SYan Zheng 365319b546d7SQu Wenruo if (btrfs_header_owner(leaf) != BTRFS_ROOT_TREE_OBJECTID) 365419b546d7SQu Wenruo return 0; 36555d4f98a2SYan Zheng 365619b546d7SQu Wenruo for (i = 0; i < btrfs_header_nritems(leaf); i++) { 365719b546d7SQu Wenruo btrfs_item_key_to_cpu(leaf, &key, i); 365819b546d7SQu Wenruo if (key.type != BTRFS_EXTENT_DATA_KEY) 365919b546d7SQu Wenruo continue; 366019b546d7SQu Wenruo ei = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 366119b546d7SQu Wenruo if (btrfs_file_extent_type(leaf, ei) == BTRFS_FILE_EXTENT_REG && 366219b546d7SQu Wenruo btrfs_file_extent_disk_bytenr(leaf, ei) == data_bytenr) { 366319b546d7SQu Wenruo found = true; 366419b546d7SQu Wenruo space_cache_ino = key.objectid; 366519b546d7SQu Wenruo break; 366619b546d7SQu Wenruo } 366719b546d7SQu Wenruo } 366819b546d7SQu Wenruo if (!found) 366919b546d7SQu Wenruo return -ENOENT; 367019b546d7SQu Wenruo ret = delete_block_group_cache(leaf->fs_info, block_group, NULL, 367119b546d7SQu Wenruo space_cache_ino); 36720af3d00bSJosef Bacik return ret; 36735d4f98a2SYan Zheng } 36745d4f98a2SYan Zheng 36755d4f98a2SYan Zheng /* 36762c016dc2SLiu Bo * helper to find all tree blocks that reference a given data extent 36775d4f98a2SYan Zheng */ 36785d4f98a2SYan Zheng static noinline_for_stack 36795d4f98a2SYan Zheng int add_data_references(struct reloc_control *rc, 36805d4f98a2SYan Zheng struct btrfs_key *extent_key, 36815d4f98a2SYan Zheng struct btrfs_path *path, 36825d4f98a2SYan Zheng struct rb_root *blocks) 36835d4f98a2SYan Zheng { 368419b546d7SQu Wenruo struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 368519b546d7SQu Wenruo struct ulist *leaves = NULL; 368619b546d7SQu Wenruo struct ulist_iterator leaf_uiter; 368719b546d7SQu Wenruo struct ulist_node *ref_node = NULL; 368819b546d7SQu Wenruo const u32 blocksize = fs_info->nodesize; 3689647f63bdSFilipe David Borba Manana int ret = 0; 36905d4f98a2SYan Zheng 3691b3b4aa74SDavid Sterba btrfs_release_path(path); 369219b546d7SQu Wenruo ret = btrfs_find_all_leafs(NULL, fs_info, extent_key->objectid, 369319b546d7SQu Wenruo 0, &leaves, NULL, true); 369419b546d7SQu Wenruo if (ret < 0) 369519b546d7SQu Wenruo return ret; 369619b546d7SQu Wenruo 369719b546d7SQu Wenruo ULIST_ITER_INIT(&leaf_uiter); 369819b546d7SQu Wenruo while ((ref_node = ulist_next(leaves, &leaf_uiter))) { 369919b546d7SQu Wenruo struct extent_buffer *eb; 370019b546d7SQu Wenruo 370119b546d7SQu Wenruo eb = read_tree_block(fs_info, ref_node->val, 0, 0, NULL); 370219b546d7SQu Wenruo if (IS_ERR(eb)) { 370319b546d7SQu Wenruo ret = PTR_ERR(eb); 370419b546d7SQu Wenruo break; 370519b546d7SQu Wenruo } 370619b546d7SQu Wenruo ret = delete_v1_space_cache(eb, rc->block_group, 370719b546d7SQu Wenruo extent_key->objectid); 370819b546d7SQu Wenruo free_extent_buffer(eb); 370919b546d7SQu Wenruo if (ret < 0) 371019b546d7SQu Wenruo break; 371119b546d7SQu Wenruo ret = __add_tree_block(rc, ref_node->val, blocksize, blocks); 371219b546d7SQu Wenruo if (ret < 0) 371319b546d7SQu Wenruo break; 371419b546d7SQu Wenruo } 371519b546d7SQu Wenruo if (ret < 0) 37165d4f98a2SYan Zheng free_block_list(blocks); 371719b546d7SQu Wenruo ulist_free(leaves); 371819b546d7SQu Wenruo return ret; 37195d4f98a2SYan Zheng } 37205d4f98a2SYan Zheng 37215d4f98a2SYan Zheng /* 37222c016dc2SLiu Bo * helper to find next unprocessed extent 37235d4f98a2SYan Zheng */ 37245d4f98a2SYan Zheng static noinline_for_stack 3725147d256eSZhaolei int find_next_extent(struct reloc_control *rc, struct btrfs_path *path, 37263fd0a558SYan, Zheng struct btrfs_key *extent_key) 37275d4f98a2SYan Zheng { 37280b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 37295d4f98a2SYan Zheng struct btrfs_key key; 37305d4f98a2SYan Zheng struct extent_buffer *leaf; 37315d4f98a2SYan Zheng u64 start, end, last; 37325d4f98a2SYan Zheng int ret; 37335d4f98a2SYan Zheng 3734b3470b5dSDavid Sterba last = rc->block_group->start + rc->block_group->length; 37355d4f98a2SYan Zheng while (1) { 37365d4f98a2SYan Zheng cond_resched(); 37375d4f98a2SYan Zheng if (rc->search_start >= last) { 37385d4f98a2SYan Zheng ret = 1; 37395d4f98a2SYan Zheng break; 37405d4f98a2SYan Zheng } 37415d4f98a2SYan Zheng 37425d4f98a2SYan Zheng key.objectid = rc->search_start; 37435d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 37445d4f98a2SYan Zheng key.offset = 0; 37455d4f98a2SYan Zheng 37465d4f98a2SYan Zheng path->search_commit_root = 1; 37475d4f98a2SYan Zheng path->skip_locking = 1; 37485d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 37495d4f98a2SYan Zheng 0, 0); 37505d4f98a2SYan Zheng if (ret < 0) 37515d4f98a2SYan Zheng break; 37525d4f98a2SYan Zheng next: 37535d4f98a2SYan Zheng leaf = path->nodes[0]; 37545d4f98a2SYan Zheng if (path->slots[0] >= btrfs_header_nritems(leaf)) { 37555d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 37565d4f98a2SYan Zheng if (ret != 0) 37575d4f98a2SYan Zheng break; 37585d4f98a2SYan Zheng leaf = path->nodes[0]; 37595d4f98a2SYan Zheng } 37605d4f98a2SYan Zheng 37615d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 37625d4f98a2SYan Zheng if (key.objectid >= last) { 37635d4f98a2SYan Zheng ret = 1; 37645d4f98a2SYan Zheng break; 37655d4f98a2SYan Zheng } 37665d4f98a2SYan Zheng 37673173a18fSJosef Bacik if (key.type != BTRFS_EXTENT_ITEM_KEY && 37683173a18fSJosef Bacik key.type != BTRFS_METADATA_ITEM_KEY) { 37693173a18fSJosef Bacik path->slots[0]++; 37703173a18fSJosef Bacik goto next; 37713173a18fSJosef Bacik } 37723173a18fSJosef Bacik 37733173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY && 37745d4f98a2SYan Zheng key.objectid + key.offset <= rc->search_start) { 37755d4f98a2SYan Zheng path->slots[0]++; 37765d4f98a2SYan Zheng goto next; 37775d4f98a2SYan Zheng } 37785d4f98a2SYan Zheng 37793173a18fSJosef Bacik if (key.type == BTRFS_METADATA_ITEM_KEY && 37800b246afaSJeff Mahoney key.objectid + fs_info->nodesize <= 37813173a18fSJosef Bacik rc->search_start) { 37823173a18fSJosef Bacik path->slots[0]++; 37833173a18fSJosef Bacik goto next; 37843173a18fSJosef Bacik } 37853173a18fSJosef Bacik 37865d4f98a2SYan Zheng ret = find_first_extent_bit(&rc->processed_blocks, 37875d4f98a2SYan Zheng key.objectid, &start, &end, 3788e6138876SJosef Bacik EXTENT_DIRTY, NULL); 37895d4f98a2SYan Zheng 37905d4f98a2SYan Zheng if (ret == 0 && start <= key.objectid) { 3791b3b4aa74SDavid Sterba btrfs_release_path(path); 37925d4f98a2SYan Zheng rc->search_start = end + 1; 37935d4f98a2SYan Zheng } else { 37943173a18fSJosef Bacik if (key.type == BTRFS_EXTENT_ITEM_KEY) 37955d4f98a2SYan Zheng rc->search_start = key.objectid + key.offset; 37963173a18fSJosef Bacik else 37973173a18fSJosef Bacik rc->search_start = key.objectid + 37980b246afaSJeff Mahoney fs_info->nodesize; 37993fd0a558SYan, Zheng memcpy(extent_key, &key, sizeof(key)); 38005d4f98a2SYan Zheng return 0; 38015d4f98a2SYan Zheng } 38025d4f98a2SYan Zheng } 3803b3b4aa74SDavid Sterba btrfs_release_path(path); 38045d4f98a2SYan Zheng return ret; 38055d4f98a2SYan Zheng } 38065d4f98a2SYan Zheng 38075d4f98a2SYan Zheng static void set_reloc_control(struct reloc_control *rc) 38085d4f98a2SYan Zheng { 38095d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 38107585717fSChris Mason 38117585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 38125d4f98a2SYan Zheng fs_info->reloc_ctl = rc; 38137585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 38145d4f98a2SYan Zheng } 38155d4f98a2SYan Zheng 38165d4f98a2SYan Zheng static void unset_reloc_control(struct reloc_control *rc) 38175d4f98a2SYan Zheng { 38185d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 38197585717fSChris Mason 38207585717fSChris Mason mutex_lock(&fs_info->reloc_mutex); 38215d4f98a2SYan Zheng fs_info->reloc_ctl = NULL; 38227585717fSChris Mason mutex_unlock(&fs_info->reloc_mutex); 38235d4f98a2SYan Zheng } 38245d4f98a2SYan Zheng 38255d4f98a2SYan Zheng static int check_extent_flags(u64 flags) 38265d4f98a2SYan Zheng { 38275d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 38285d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 38295d4f98a2SYan Zheng return 1; 38305d4f98a2SYan Zheng if (!(flags & BTRFS_EXTENT_FLAG_DATA) && 38315d4f98a2SYan Zheng !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 38325d4f98a2SYan Zheng return 1; 38335d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 38345d4f98a2SYan Zheng (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) 38355d4f98a2SYan Zheng return 1; 38365d4f98a2SYan Zheng return 0; 38375d4f98a2SYan Zheng } 38385d4f98a2SYan Zheng 38393fd0a558SYan, Zheng static noinline_for_stack 38403fd0a558SYan, Zheng int prepare_to_relocate(struct reloc_control *rc) 38413fd0a558SYan, Zheng { 38423fd0a558SYan, Zheng struct btrfs_trans_handle *trans; 3843ac2fabacSJosef Bacik int ret; 38443fd0a558SYan, Zheng 38452ff7e61eSJeff Mahoney rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root->fs_info, 384666d8f3ddSMiao Xie BTRFS_BLOCK_RSV_TEMP); 38473fd0a558SYan, Zheng if (!rc->block_rsv) 38483fd0a558SYan, Zheng return -ENOMEM; 38493fd0a558SYan, Zheng 38503fd0a558SYan, Zheng memset(&rc->cluster, 0, sizeof(rc->cluster)); 3851b3470b5dSDavid Sterba rc->search_start = rc->block_group->start; 38523fd0a558SYan, Zheng rc->extents_found = 0; 38533fd0a558SYan, Zheng rc->nodes_relocated = 0; 38543fd0a558SYan, Zheng rc->merging_rsv_size = 0; 38550647bf56SWang Shilong rc->reserved_bytes = 0; 3856da17066cSJeff Mahoney rc->block_rsv->size = rc->extent_root->fs_info->nodesize * 38570647bf56SWang Shilong RELOCATION_RESERVED_NODES; 3858ac2fabacSJosef Bacik ret = btrfs_block_rsv_refill(rc->extent_root, 3859ac2fabacSJosef Bacik rc->block_rsv, rc->block_rsv->size, 3860ac2fabacSJosef Bacik BTRFS_RESERVE_FLUSH_ALL); 3861ac2fabacSJosef Bacik if (ret) 3862ac2fabacSJosef Bacik return ret; 38633fd0a558SYan, Zheng 38643fd0a558SYan, Zheng rc->create_reloc_tree = 1; 38653fd0a558SYan, Zheng set_reloc_control(rc); 38663fd0a558SYan, Zheng 38677a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 386828818947SLiu Bo if (IS_ERR(trans)) { 386928818947SLiu Bo unset_reloc_control(rc); 387028818947SLiu Bo /* 387128818947SLiu Bo * extent tree is not a ref_cow tree and has no reloc_root to 387228818947SLiu Bo * cleanup. And callers are responsible to free the above 387328818947SLiu Bo * block rsv. 387428818947SLiu Bo */ 387528818947SLiu Bo return PTR_ERR(trans); 387628818947SLiu Bo } 38773a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 38783fd0a558SYan, Zheng return 0; 38793fd0a558SYan, Zheng } 388076dda93cSYan, Zheng 38815d4f98a2SYan Zheng static noinline_for_stack int relocate_block_group(struct reloc_control *rc) 38825d4f98a2SYan Zheng { 38832ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 38845d4f98a2SYan Zheng struct rb_root blocks = RB_ROOT; 38855d4f98a2SYan Zheng struct btrfs_key key; 38865d4f98a2SYan Zheng struct btrfs_trans_handle *trans = NULL; 38875d4f98a2SYan Zheng struct btrfs_path *path; 38885d4f98a2SYan Zheng struct btrfs_extent_item *ei; 38895d4f98a2SYan Zheng u64 flags; 38905d4f98a2SYan Zheng u32 item_size; 38915d4f98a2SYan Zheng int ret; 38925d4f98a2SYan Zheng int err = 0; 3893c87f08caSChris Mason int progress = 0; 38945d4f98a2SYan Zheng 38955d4f98a2SYan Zheng path = btrfs_alloc_path(); 38963fd0a558SYan, Zheng if (!path) 38975d4f98a2SYan Zheng return -ENOMEM; 3898e4058b54SDavid Sterba path->reada = READA_FORWARD; 38993fd0a558SYan, Zheng 39003fd0a558SYan, Zheng ret = prepare_to_relocate(rc); 39013fd0a558SYan, Zheng if (ret) { 39023fd0a558SYan, Zheng err = ret; 39033fd0a558SYan, Zheng goto out_free; 39042423fdfbSJiri Slaby } 39055d4f98a2SYan Zheng 39065d4f98a2SYan Zheng while (1) { 39070647bf56SWang Shilong rc->reserved_bytes = 0; 39080647bf56SWang Shilong ret = btrfs_block_rsv_refill(rc->extent_root, 39090647bf56SWang Shilong rc->block_rsv, rc->block_rsv->size, 39100647bf56SWang Shilong BTRFS_RESERVE_FLUSH_ALL); 39110647bf56SWang Shilong if (ret) { 39120647bf56SWang Shilong err = ret; 39130647bf56SWang Shilong break; 39140647bf56SWang Shilong } 3915c87f08caSChris Mason progress++; 3916a22285a6SYan, Zheng trans = btrfs_start_transaction(rc->extent_root, 0); 39170f788c58SLiu Bo if (IS_ERR(trans)) { 39180f788c58SLiu Bo err = PTR_ERR(trans); 39190f788c58SLiu Bo trans = NULL; 39200f788c58SLiu Bo break; 39210f788c58SLiu Bo } 3922c87f08caSChris Mason restart: 39233fd0a558SYan, Zheng if (update_backref_cache(trans, &rc->backref_cache)) { 39243a45bb20SJeff Mahoney btrfs_end_transaction(trans); 392542a657f5SPan Bian trans = NULL; 39263fd0a558SYan, Zheng continue; 39273fd0a558SYan, Zheng } 39283fd0a558SYan, Zheng 3929147d256eSZhaolei ret = find_next_extent(rc, path, &key); 39305d4f98a2SYan Zheng if (ret < 0) 39315d4f98a2SYan Zheng err = ret; 39325d4f98a2SYan Zheng if (ret != 0) 39335d4f98a2SYan Zheng break; 39345d4f98a2SYan Zheng 39355d4f98a2SYan Zheng rc->extents_found++; 39365d4f98a2SYan Zheng 39375d4f98a2SYan Zheng ei = btrfs_item_ptr(path->nodes[0], path->slots[0], 39385d4f98a2SYan Zheng struct btrfs_extent_item); 39393fd0a558SYan, Zheng item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); 39405d4f98a2SYan Zheng if (item_size >= sizeof(*ei)) { 39415d4f98a2SYan Zheng flags = btrfs_extent_flags(path->nodes[0], ei); 39425d4f98a2SYan Zheng ret = check_extent_flags(flags); 39435d4f98a2SYan Zheng BUG_ON(ret); 39446d8ff4e4SDavid Sterba } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) { 3945ba3c2b19SNikolay Borisov err = -EINVAL; 3946ba3c2b19SNikolay Borisov btrfs_print_v0_err(trans->fs_info); 3947ba3c2b19SNikolay Borisov btrfs_abort_transaction(trans, err); 3948ba3c2b19SNikolay Borisov break; 39495d4f98a2SYan Zheng } else { 39505d4f98a2SYan Zheng BUG(); 39515d4f98a2SYan Zheng } 39525d4f98a2SYan Zheng 39535d4f98a2SYan Zheng if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 39545d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, &blocks); 39555d4f98a2SYan Zheng } else if (rc->stage == UPDATE_DATA_PTRS && 39565d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 39575d4f98a2SYan Zheng ret = add_data_references(rc, &key, path, &blocks); 39585d4f98a2SYan Zheng } else { 3959b3b4aa74SDavid Sterba btrfs_release_path(path); 39605d4f98a2SYan Zheng ret = 0; 39615d4f98a2SYan Zheng } 39625d4f98a2SYan Zheng if (ret < 0) { 39633fd0a558SYan, Zheng err = ret; 39645d4f98a2SYan Zheng break; 39655d4f98a2SYan Zheng } 39665d4f98a2SYan Zheng 39675d4f98a2SYan Zheng if (!RB_EMPTY_ROOT(&blocks)) { 39685d4f98a2SYan Zheng ret = relocate_tree_blocks(trans, rc, &blocks); 39695d4f98a2SYan Zheng if (ret < 0) { 39703fd0a558SYan, Zheng if (ret != -EAGAIN) { 39715d4f98a2SYan Zheng err = ret; 39725d4f98a2SYan Zheng break; 39735d4f98a2SYan Zheng } 39743fd0a558SYan, Zheng rc->extents_found--; 39753fd0a558SYan, Zheng rc->search_start = key.objectid; 39763fd0a558SYan, Zheng } 39775d4f98a2SYan Zheng } 39785d4f98a2SYan Zheng 39793a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 39802ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 39813fd0a558SYan, Zheng trans = NULL; 39825d4f98a2SYan Zheng 39835d4f98a2SYan Zheng if (rc->stage == MOVE_DATA_EXTENTS && 39845d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 39855d4f98a2SYan Zheng rc->found_file_extent = 1; 39860257bb82SYan, Zheng ret = relocate_data_extent(rc->data_inode, 39873fd0a558SYan, Zheng &key, &rc->cluster); 39885d4f98a2SYan Zheng if (ret < 0) { 39895d4f98a2SYan Zheng err = ret; 39905d4f98a2SYan Zheng break; 39915d4f98a2SYan Zheng } 39925d4f98a2SYan Zheng } 3993f31ea088SQu Wenruo if (btrfs_should_cancel_balance(fs_info)) { 3994f31ea088SQu Wenruo err = -ECANCELED; 3995f31ea088SQu Wenruo break; 3996f31ea088SQu Wenruo } 39975d4f98a2SYan Zheng } 3998c87f08caSChris Mason if (trans && progress && err == -ENOSPC) { 399943a7e99dSNikolay Borisov ret = btrfs_force_chunk_alloc(trans, rc->block_group->flags); 40009689457bSShilong Wang if (ret == 1) { 4001c87f08caSChris Mason err = 0; 4002c87f08caSChris Mason progress = 0; 4003c87f08caSChris Mason goto restart; 4004c87f08caSChris Mason } 4005c87f08caSChris Mason } 40063fd0a558SYan, Zheng 4007b3b4aa74SDavid Sterba btrfs_release_path(path); 400891166212SDavid Sterba clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY); 40095d4f98a2SYan Zheng 40105d4f98a2SYan Zheng if (trans) { 40113a45bb20SJeff Mahoney btrfs_end_transaction_throttle(trans); 40122ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 40135d4f98a2SYan Zheng } 40145d4f98a2SYan Zheng 40150257bb82SYan, Zheng if (!err) { 40163fd0a558SYan, Zheng ret = relocate_file_extent_cluster(rc->data_inode, 40173fd0a558SYan, Zheng &rc->cluster); 40180257bb82SYan, Zheng if (ret < 0) 40190257bb82SYan, Zheng err = ret; 40200257bb82SYan, Zheng } 40210257bb82SYan, Zheng 40223fd0a558SYan, Zheng rc->create_reloc_tree = 0; 40233fd0a558SYan, Zheng set_reloc_control(rc); 40240257bb82SYan, Zheng 40253fd0a558SYan, Zheng backref_cache_cleanup(&rc->backref_cache); 402663f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 40275d4f98a2SYan Zheng 40287f913c7cSQu Wenruo /* 40297f913c7cSQu Wenruo * Even in the case when the relocation is cancelled, we should all go 40307f913c7cSQu Wenruo * through prepare_to_merge() and merge_reloc_roots(). 40317f913c7cSQu Wenruo * 40327f913c7cSQu Wenruo * For error (including cancelled balance), prepare_to_merge() will 40337f913c7cSQu Wenruo * mark all reloc trees orphan, then queue them for cleanup in 40347f913c7cSQu Wenruo * merge_reloc_roots() 40357f913c7cSQu Wenruo */ 40363fd0a558SYan, Zheng err = prepare_to_merge(rc, err); 40375d4f98a2SYan Zheng 40385d4f98a2SYan Zheng merge_reloc_roots(rc); 40395d4f98a2SYan Zheng 40403fd0a558SYan, Zheng rc->merge_reloc_tree = 0; 40415d4f98a2SYan Zheng unset_reloc_control(rc); 404263f018beSNikolay Borisov btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1, NULL); 40435d4f98a2SYan Zheng 40445d4f98a2SYan Zheng /* get rid of pinned extents */ 40457a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 404662b99540SQu Wenruo if (IS_ERR(trans)) { 40473612b495STsutomu Itoh err = PTR_ERR(trans); 404862b99540SQu Wenruo goto out_free; 404962b99540SQu Wenruo } 40503a45bb20SJeff Mahoney btrfs_commit_transaction(trans); 40516217b0faSJosef Bacik out_free: 4052d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 4053d2311e69SQu Wenruo if (ret < 0 && !err) 4054d2311e69SQu Wenruo err = ret; 40552ff7e61eSJeff Mahoney btrfs_free_block_rsv(fs_info, rc->block_rsv); 40563fd0a558SYan, Zheng btrfs_free_path(path); 40575d4f98a2SYan Zheng return err; 40585d4f98a2SYan Zheng } 40595d4f98a2SYan Zheng 40605d4f98a2SYan Zheng static int __insert_orphan_inode(struct btrfs_trans_handle *trans, 40610257bb82SYan, Zheng struct btrfs_root *root, u64 objectid) 40625d4f98a2SYan Zheng { 40635d4f98a2SYan Zheng struct btrfs_path *path; 40645d4f98a2SYan Zheng struct btrfs_inode_item *item; 40655d4f98a2SYan Zheng struct extent_buffer *leaf; 40665d4f98a2SYan Zheng int ret; 40675d4f98a2SYan Zheng 40685d4f98a2SYan Zheng path = btrfs_alloc_path(); 40695d4f98a2SYan Zheng if (!path) 40705d4f98a2SYan Zheng return -ENOMEM; 40715d4f98a2SYan Zheng 40725d4f98a2SYan Zheng ret = btrfs_insert_empty_inode(trans, root, path, objectid); 40735d4f98a2SYan Zheng if (ret) 40745d4f98a2SYan Zheng goto out; 40755d4f98a2SYan Zheng 40765d4f98a2SYan Zheng leaf = path->nodes[0]; 40775d4f98a2SYan Zheng item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); 4078b159fa28SDavid Sterba memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item)); 40795d4f98a2SYan Zheng btrfs_set_inode_generation(leaf, item, 1); 40800257bb82SYan, Zheng btrfs_set_inode_size(leaf, item, 0); 40815d4f98a2SYan Zheng btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); 40823fd0a558SYan, Zheng btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS | 40833fd0a558SYan, Zheng BTRFS_INODE_PREALLOC); 40845d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 40855d4f98a2SYan Zheng out: 40865d4f98a2SYan Zheng btrfs_free_path(path); 40875d4f98a2SYan Zheng return ret; 40885d4f98a2SYan Zheng } 40895d4f98a2SYan Zheng 40905d4f98a2SYan Zheng /* 40915d4f98a2SYan Zheng * helper to create inode for data relocation. 40925d4f98a2SYan Zheng * the inode is in data relocation tree and its link count is 0 40935d4f98a2SYan Zheng */ 40943fd0a558SYan, Zheng static noinline_for_stack 40953fd0a558SYan, Zheng struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, 409632da5386SDavid Sterba struct btrfs_block_group *group) 40975d4f98a2SYan Zheng { 40985d4f98a2SYan Zheng struct inode *inode = NULL; 40995d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 41005d4f98a2SYan Zheng struct btrfs_root *root; 41015d4f98a2SYan Zheng struct btrfs_key key; 41024624900dSZhaolei u64 objectid; 41035d4f98a2SYan Zheng int err = 0; 41045d4f98a2SYan Zheng 41055d4f98a2SYan Zheng root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 41065d4f98a2SYan Zheng if (IS_ERR(root)) 41075d4f98a2SYan Zheng return ERR_CAST(root); 41085d4f98a2SYan Zheng 4109a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 6); 411076deacf0SJosef Bacik if (IS_ERR(trans)) { 411100246528SJosef Bacik btrfs_put_root(root); 41123fd0a558SYan, Zheng return ERR_CAST(trans); 411376deacf0SJosef Bacik } 41145d4f98a2SYan Zheng 4115581bb050SLi Zefan err = btrfs_find_free_objectid(root, &objectid); 41165d4f98a2SYan Zheng if (err) 41175d4f98a2SYan Zheng goto out; 41185d4f98a2SYan Zheng 41190257bb82SYan, Zheng err = __insert_orphan_inode(trans, root, objectid); 41205d4f98a2SYan Zheng BUG_ON(err); 41215d4f98a2SYan Zheng 41225d4f98a2SYan Zheng key.objectid = objectid; 41235d4f98a2SYan Zheng key.type = BTRFS_INODE_ITEM_KEY; 41245d4f98a2SYan Zheng key.offset = 0; 41254c66e0d4SDavid Sterba inode = btrfs_iget(fs_info->sb, &key, root); 41262e19f1f9SAl Viro BUG_ON(IS_ERR(inode)); 4127b3470b5dSDavid Sterba BTRFS_I(inode)->index_cnt = group->start; 41285d4f98a2SYan Zheng 412973f2e545SNikolay Borisov err = btrfs_orphan_add(trans, BTRFS_I(inode)); 41305d4f98a2SYan Zheng out: 413100246528SJosef Bacik btrfs_put_root(root); 41323a45bb20SJeff Mahoney btrfs_end_transaction(trans); 41332ff7e61eSJeff Mahoney btrfs_btree_balance_dirty(fs_info); 41345d4f98a2SYan Zheng if (err) { 41355d4f98a2SYan Zheng if (inode) 41365d4f98a2SYan Zheng iput(inode); 41375d4f98a2SYan Zheng inode = ERR_PTR(err); 41385d4f98a2SYan Zheng } 41395d4f98a2SYan Zheng return inode; 41405d4f98a2SYan Zheng } 41415d4f98a2SYan Zheng 4142c258d6e3SQu Wenruo static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info) 41433fd0a558SYan, Zheng { 41443fd0a558SYan, Zheng struct reloc_control *rc; 41453fd0a558SYan, Zheng 41463fd0a558SYan, Zheng rc = kzalloc(sizeof(*rc), GFP_NOFS); 41473fd0a558SYan, Zheng if (!rc) 41483fd0a558SYan, Zheng return NULL; 41493fd0a558SYan, Zheng 41503fd0a558SYan, Zheng INIT_LIST_HEAD(&rc->reloc_roots); 4151d2311e69SQu Wenruo INIT_LIST_HEAD(&rc->dirty_subvol_roots); 4152584fb121SQu Wenruo btrfs_backref_init_cache(fs_info, &rc->backref_cache, 1); 41533fd0a558SYan, Zheng mapping_tree_init(&rc->reloc_root_tree); 415443eb5f29SQu Wenruo extent_io_tree_init(fs_info, &rc->processed_blocks, 415543eb5f29SQu Wenruo IO_TREE_RELOC_BLOCKS, NULL); 41563fd0a558SYan, Zheng return rc; 41573fd0a558SYan, Zheng } 41583fd0a558SYan, Zheng 41591a0afa0eSJosef Bacik static void free_reloc_control(struct reloc_control *rc) 41601a0afa0eSJosef Bacik { 41611a0afa0eSJosef Bacik struct mapping_node *node, *tmp; 41621a0afa0eSJosef Bacik 41631a0afa0eSJosef Bacik free_reloc_roots(&rc->reloc_roots); 41641a0afa0eSJosef Bacik rbtree_postorder_for_each_entry_safe(node, tmp, 41651a0afa0eSJosef Bacik &rc->reloc_root_tree.rb_root, rb_node) 41661a0afa0eSJosef Bacik kfree(node); 41671a0afa0eSJosef Bacik 41681a0afa0eSJosef Bacik kfree(rc); 41691a0afa0eSJosef Bacik } 41701a0afa0eSJosef Bacik 41715d4f98a2SYan Zheng /* 4172ebce0e01SAdam Borowski * Print the block group being relocated 4173ebce0e01SAdam Borowski */ 4174ebce0e01SAdam Borowski static void describe_relocation(struct btrfs_fs_info *fs_info, 417532da5386SDavid Sterba struct btrfs_block_group *block_group) 4176ebce0e01SAdam Borowski { 4177f89e09cfSAnand Jain char buf[128] = {'\0'}; 4178ebce0e01SAdam Borowski 4179f89e09cfSAnand Jain btrfs_describe_block_groups(block_group->flags, buf, sizeof(buf)); 4180ebce0e01SAdam Borowski 4181ebce0e01SAdam Borowski btrfs_info(fs_info, 4182ebce0e01SAdam Borowski "relocating block group %llu flags %s", 4183b3470b5dSDavid Sterba block_group->start, buf); 4184ebce0e01SAdam Borowski } 4185ebce0e01SAdam Borowski 4186430640e3SQu Wenruo static const char *stage_to_string(int stage) 4187430640e3SQu Wenruo { 4188430640e3SQu Wenruo if (stage == MOVE_DATA_EXTENTS) 4189430640e3SQu Wenruo return "move data extents"; 4190430640e3SQu Wenruo if (stage == UPDATE_DATA_PTRS) 4191430640e3SQu Wenruo return "update data pointers"; 4192430640e3SQu Wenruo return "unknown"; 4193430640e3SQu Wenruo } 4194430640e3SQu Wenruo 4195ebce0e01SAdam Borowski /* 41965d4f98a2SYan Zheng * function to relocate all extents in a block group. 41975d4f98a2SYan Zheng */ 41986bccf3abSJeff Mahoney int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start) 41995d4f98a2SYan Zheng { 420032da5386SDavid Sterba struct btrfs_block_group *bg; 42016bccf3abSJeff Mahoney struct btrfs_root *extent_root = fs_info->extent_root; 42025d4f98a2SYan Zheng struct reloc_control *rc; 42030af3d00bSJosef Bacik struct inode *inode; 42040af3d00bSJosef Bacik struct btrfs_path *path; 42055d4f98a2SYan Zheng int ret; 4206f0486c68SYan, Zheng int rw = 0; 42075d4f98a2SYan Zheng int err = 0; 42085d4f98a2SYan Zheng 4209eede2bf3SOmar Sandoval bg = btrfs_lookup_block_group(fs_info, group_start); 4210eede2bf3SOmar Sandoval if (!bg) 4211eede2bf3SOmar Sandoval return -ENOENT; 4212eede2bf3SOmar Sandoval 4213eede2bf3SOmar Sandoval if (btrfs_pinned_by_swapfile(fs_info, bg)) { 4214eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 4215eede2bf3SOmar Sandoval return -ETXTBSY; 4216eede2bf3SOmar Sandoval } 4217eede2bf3SOmar Sandoval 4218c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 4219eede2bf3SOmar Sandoval if (!rc) { 4220eede2bf3SOmar Sandoval btrfs_put_block_group(bg); 42215d4f98a2SYan Zheng return -ENOMEM; 4222eede2bf3SOmar Sandoval } 42235d4f98a2SYan Zheng 4224f0486c68SYan, Zheng rc->extent_root = extent_root; 4225eede2bf3SOmar Sandoval rc->block_group = bg; 42265d4f98a2SYan Zheng 4227b12de528SQu Wenruo ret = btrfs_inc_block_group_ro(rc->block_group, true); 4228f0486c68SYan, Zheng if (ret) { 4229f0486c68SYan, Zheng err = ret; 4230f0486c68SYan, Zheng goto out; 4231f0486c68SYan, Zheng } 4232f0486c68SYan, Zheng rw = 1; 4233f0486c68SYan, Zheng 42340af3d00bSJosef Bacik path = btrfs_alloc_path(); 42350af3d00bSJosef Bacik if (!path) { 42360af3d00bSJosef Bacik err = -ENOMEM; 42370af3d00bSJosef Bacik goto out; 42380af3d00bSJosef Bacik } 42390af3d00bSJosef Bacik 42407949f339SDavid Sterba inode = lookup_free_space_inode(rc->block_group, path); 42410af3d00bSJosef Bacik btrfs_free_path(path); 42420af3d00bSJosef Bacik 42430af3d00bSJosef Bacik if (!IS_ERR(inode)) 42441bbc621eSChris Mason ret = delete_block_group_cache(fs_info, rc->block_group, inode, 0); 42450af3d00bSJosef Bacik else 42460af3d00bSJosef Bacik ret = PTR_ERR(inode); 42470af3d00bSJosef Bacik 42480af3d00bSJosef Bacik if (ret && ret != -ENOENT) { 42490af3d00bSJosef Bacik err = ret; 42500af3d00bSJosef Bacik goto out; 42510af3d00bSJosef Bacik } 42520af3d00bSJosef Bacik 42535d4f98a2SYan Zheng rc->data_inode = create_reloc_inode(fs_info, rc->block_group); 42545d4f98a2SYan Zheng if (IS_ERR(rc->data_inode)) { 42555d4f98a2SYan Zheng err = PTR_ERR(rc->data_inode); 42565d4f98a2SYan Zheng rc->data_inode = NULL; 42575d4f98a2SYan Zheng goto out; 42585d4f98a2SYan Zheng } 42595d4f98a2SYan Zheng 42600b246afaSJeff Mahoney describe_relocation(fs_info, rc->block_group); 42615d4f98a2SYan Zheng 42629cfa3e34SFilipe Manana btrfs_wait_block_group_reservations(rc->block_group); 4263f78c436cSFilipe Manana btrfs_wait_nocow_writers(rc->block_group); 42646374e57aSChris Mason btrfs_wait_ordered_roots(fs_info, U64_MAX, 4265b3470b5dSDavid Sterba rc->block_group->start, 4266b3470b5dSDavid Sterba rc->block_group->length); 42675d4f98a2SYan Zheng 42685d4f98a2SYan Zheng while (1) { 4269430640e3SQu Wenruo int finishes_stage; 4270430640e3SQu Wenruo 427176dda93cSYan, Zheng mutex_lock(&fs_info->cleaner_mutex); 42725d4f98a2SYan Zheng ret = relocate_block_group(rc); 427376dda93cSYan, Zheng mutex_unlock(&fs_info->cleaner_mutex); 4274ff612ba7SJosef Bacik if (ret < 0) 42755d4f98a2SYan Zheng err = ret; 4276ff612ba7SJosef Bacik 4277430640e3SQu Wenruo finishes_stage = rc->stage; 4278ff612ba7SJosef Bacik /* 4279ff612ba7SJosef Bacik * We may have gotten ENOSPC after we already dirtied some 4280ff612ba7SJosef Bacik * extents. If writeout happens while we're relocating a 4281ff612ba7SJosef Bacik * different block group we could end up hitting the 4282ff612ba7SJosef Bacik * BUG_ON(rc->stage == UPDATE_DATA_PTRS) in 4283ff612ba7SJosef Bacik * btrfs_reloc_cow_block. Make sure we write everything out 4284ff612ba7SJosef Bacik * properly so we don't trip over this problem, and then break 4285ff612ba7SJosef Bacik * out of the loop if we hit an error. 4286ff612ba7SJosef Bacik */ 4287ff612ba7SJosef Bacik if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { 4288ff612ba7SJosef Bacik ret = btrfs_wait_ordered_range(rc->data_inode, 0, 4289ff612ba7SJosef Bacik (u64)-1); 4290ff612ba7SJosef Bacik if (ret) 4291ff612ba7SJosef Bacik err = ret; 4292ff612ba7SJosef Bacik invalidate_mapping_pages(rc->data_inode->i_mapping, 4293ff612ba7SJosef Bacik 0, -1); 4294ff612ba7SJosef Bacik rc->stage = UPDATE_DATA_PTRS; 42955d4f98a2SYan Zheng } 42965d4f98a2SYan Zheng 4297ff612ba7SJosef Bacik if (err < 0) 4298ff612ba7SJosef Bacik goto out; 4299ff612ba7SJosef Bacik 43005d4f98a2SYan Zheng if (rc->extents_found == 0) 43015d4f98a2SYan Zheng break; 43025d4f98a2SYan Zheng 4303430640e3SQu Wenruo btrfs_info(fs_info, "found %llu extents, stage: %s", 4304430640e3SQu Wenruo rc->extents_found, stage_to_string(finishes_stage)); 43055d4f98a2SYan Zheng } 43065d4f98a2SYan Zheng 43075d4f98a2SYan Zheng WARN_ON(rc->block_group->pinned > 0); 43085d4f98a2SYan Zheng WARN_ON(rc->block_group->reserved > 0); 4309bf38be65SDavid Sterba WARN_ON(rc->block_group->used > 0); 43105d4f98a2SYan Zheng out: 4311f0486c68SYan, Zheng if (err && rw) 43122ff7e61eSJeff Mahoney btrfs_dec_block_group_ro(rc->block_group); 43135d4f98a2SYan Zheng iput(rc->data_inode); 43145d4f98a2SYan Zheng btrfs_put_block_group(rc->block_group); 43151a0afa0eSJosef Bacik free_reloc_control(rc); 43165d4f98a2SYan Zheng return err; 43175d4f98a2SYan Zheng } 43185d4f98a2SYan Zheng 431976dda93cSYan, Zheng static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) 432076dda93cSYan, Zheng { 43210b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 432276dda93cSYan, Zheng struct btrfs_trans_handle *trans; 432379787eaaSJeff Mahoney int ret, err; 432476dda93cSYan, Zheng 43250b246afaSJeff Mahoney trans = btrfs_start_transaction(fs_info->tree_root, 0); 432679787eaaSJeff Mahoney if (IS_ERR(trans)) 432779787eaaSJeff Mahoney return PTR_ERR(trans); 432876dda93cSYan, Zheng 432976dda93cSYan, Zheng memset(&root->root_item.drop_progress, 0, 433076dda93cSYan, Zheng sizeof(root->root_item.drop_progress)); 433176dda93cSYan, Zheng root->root_item.drop_level = 0; 433276dda93cSYan, Zheng btrfs_set_root_refs(&root->root_item, 0); 43330b246afaSJeff Mahoney ret = btrfs_update_root(trans, fs_info->tree_root, 433476dda93cSYan, Zheng &root->root_key, &root->root_item); 433576dda93cSYan, Zheng 43363a45bb20SJeff Mahoney err = btrfs_end_transaction(trans); 433779787eaaSJeff Mahoney if (err) 433879787eaaSJeff Mahoney return err; 433979787eaaSJeff Mahoney return ret; 434076dda93cSYan, Zheng } 434176dda93cSYan, Zheng 43425d4f98a2SYan Zheng /* 43435d4f98a2SYan Zheng * recover relocation interrupted by system crash. 43445d4f98a2SYan Zheng * 43455d4f98a2SYan Zheng * this function resumes merging reloc trees with corresponding fs trees. 43465d4f98a2SYan Zheng * this is important for keeping the sharing of tree blocks 43475d4f98a2SYan Zheng */ 43485d4f98a2SYan Zheng int btrfs_recover_relocation(struct btrfs_root *root) 43495d4f98a2SYan Zheng { 43500b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 43515d4f98a2SYan Zheng LIST_HEAD(reloc_roots); 43525d4f98a2SYan Zheng struct btrfs_key key; 43535d4f98a2SYan Zheng struct btrfs_root *fs_root; 43545d4f98a2SYan Zheng struct btrfs_root *reloc_root; 43555d4f98a2SYan Zheng struct btrfs_path *path; 43565d4f98a2SYan Zheng struct extent_buffer *leaf; 43575d4f98a2SYan Zheng struct reloc_control *rc = NULL; 43585d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 43595d4f98a2SYan Zheng int ret; 43605d4f98a2SYan Zheng int err = 0; 43615d4f98a2SYan Zheng 43625d4f98a2SYan Zheng path = btrfs_alloc_path(); 43635d4f98a2SYan Zheng if (!path) 43645d4f98a2SYan Zheng return -ENOMEM; 4365e4058b54SDavid Sterba path->reada = READA_BACK; 43665d4f98a2SYan Zheng 43675d4f98a2SYan Zheng key.objectid = BTRFS_TREE_RELOC_OBJECTID; 43685d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 43695d4f98a2SYan Zheng key.offset = (u64)-1; 43705d4f98a2SYan Zheng 43715d4f98a2SYan Zheng while (1) { 43720b246afaSJeff Mahoney ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, 43735d4f98a2SYan Zheng path, 0, 0); 43745d4f98a2SYan Zheng if (ret < 0) { 43755d4f98a2SYan Zheng err = ret; 43765d4f98a2SYan Zheng goto out; 43775d4f98a2SYan Zheng } 43785d4f98a2SYan Zheng if (ret > 0) { 43795d4f98a2SYan Zheng if (path->slots[0] == 0) 43805d4f98a2SYan Zheng break; 43815d4f98a2SYan Zheng path->slots[0]--; 43825d4f98a2SYan Zheng } 43835d4f98a2SYan Zheng leaf = path->nodes[0]; 43845d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 4385b3b4aa74SDavid Sterba btrfs_release_path(path); 43865d4f98a2SYan Zheng 43875d4f98a2SYan Zheng if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || 43885d4f98a2SYan Zheng key.type != BTRFS_ROOT_ITEM_KEY) 43895d4f98a2SYan Zheng break; 43905d4f98a2SYan Zheng 43913dbf1738SJosef Bacik reloc_root = btrfs_read_tree_root(root, &key); 43925d4f98a2SYan Zheng if (IS_ERR(reloc_root)) { 43935d4f98a2SYan Zheng err = PTR_ERR(reloc_root); 43945d4f98a2SYan Zheng goto out; 43955d4f98a2SYan Zheng } 43965d4f98a2SYan Zheng 43973dbf1738SJosef Bacik set_bit(BTRFS_ROOT_REF_COWS, &reloc_root->state); 43985d4f98a2SYan Zheng list_add(&reloc_root->root_list, &reloc_roots); 43995d4f98a2SYan Zheng 44005d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 44010b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, 44025d4f98a2SYan Zheng reloc_root->root_key.offset); 44035d4f98a2SYan Zheng if (IS_ERR(fs_root)) { 440476dda93cSYan, Zheng ret = PTR_ERR(fs_root); 440576dda93cSYan, Zheng if (ret != -ENOENT) { 440676dda93cSYan, Zheng err = ret; 44075d4f98a2SYan Zheng goto out; 44085d4f98a2SYan Zheng } 440979787eaaSJeff Mahoney ret = mark_garbage_root(reloc_root); 441079787eaaSJeff Mahoney if (ret < 0) { 441179787eaaSJeff Mahoney err = ret; 441279787eaaSJeff Mahoney goto out; 441379787eaaSJeff Mahoney } 4414932fd26dSJosef Bacik } else { 441500246528SJosef Bacik btrfs_put_root(fs_root); 441676dda93cSYan, Zheng } 44175d4f98a2SYan Zheng } 44185d4f98a2SYan Zheng 44195d4f98a2SYan Zheng if (key.offset == 0) 44205d4f98a2SYan Zheng break; 44215d4f98a2SYan Zheng 44225d4f98a2SYan Zheng key.offset--; 44235d4f98a2SYan Zheng } 4424b3b4aa74SDavid Sterba btrfs_release_path(path); 44255d4f98a2SYan Zheng 44265d4f98a2SYan Zheng if (list_empty(&reloc_roots)) 44275d4f98a2SYan Zheng goto out; 44285d4f98a2SYan Zheng 4429c258d6e3SQu Wenruo rc = alloc_reloc_control(fs_info); 44305d4f98a2SYan Zheng if (!rc) { 44315d4f98a2SYan Zheng err = -ENOMEM; 44325d4f98a2SYan Zheng goto out; 44335d4f98a2SYan Zheng } 44345d4f98a2SYan Zheng 44350b246afaSJeff Mahoney rc->extent_root = fs_info->extent_root; 44365d4f98a2SYan Zheng 44375d4f98a2SYan Zheng set_reloc_control(rc); 44385d4f98a2SYan Zheng 44397a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 44403612b495STsutomu Itoh if (IS_ERR(trans)) { 44413612b495STsutomu Itoh err = PTR_ERR(trans); 4442fb2d83eeSJosef Bacik goto out_unset; 44433612b495STsutomu Itoh } 44443fd0a558SYan, Zheng 44453fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 44463fd0a558SYan, Zheng 44475d4f98a2SYan Zheng while (!list_empty(&reloc_roots)) { 44485d4f98a2SYan Zheng reloc_root = list_entry(reloc_roots.next, 44495d4f98a2SYan Zheng struct btrfs_root, root_list); 44505d4f98a2SYan Zheng list_del(&reloc_root->root_list); 44515d4f98a2SYan Zheng 44525d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) == 0) { 44535d4f98a2SYan Zheng list_add_tail(&reloc_root->root_list, 44545d4f98a2SYan Zheng &rc->reloc_roots); 44555d4f98a2SYan Zheng continue; 44565d4f98a2SYan Zheng } 44575d4f98a2SYan Zheng 44580b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, reloc_root->root_key.offset); 445979787eaaSJeff Mahoney if (IS_ERR(fs_root)) { 446079787eaaSJeff Mahoney err = PTR_ERR(fs_root); 4461ca1aa281SJosef Bacik list_add_tail(&reloc_root->root_list, &reloc_roots); 44621402d17dSXiyu Yang btrfs_end_transaction(trans); 4463fb2d83eeSJosef Bacik goto out_unset; 446479787eaaSJeff Mahoney } 44655d4f98a2SYan Zheng 4466ffd7b339SJeff Mahoney err = __add_reloc_root(reloc_root); 446779787eaaSJeff Mahoney BUG_ON(err < 0); /* -ENOMEM or logic error */ 4468f44deb74SJosef Bacik fs_root->reloc_root = btrfs_grab_root(reloc_root); 446900246528SJosef Bacik btrfs_put_root(fs_root); 44705d4f98a2SYan Zheng } 44715d4f98a2SYan Zheng 44723a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 447379787eaaSJeff Mahoney if (err) 4474fb2d83eeSJosef Bacik goto out_unset; 44755d4f98a2SYan Zheng 44765d4f98a2SYan Zheng merge_reloc_roots(rc); 44775d4f98a2SYan Zheng 44785d4f98a2SYan Zheng unset_reloc_control(rc); 44795d4f98a2SYan Zheng 44807a7eaa40SJosef Bacik trans = btrfs_join_transaction(rc->extent_root); 448162b99540SQu Wenruo if (IS_ERR(trans)) { 44823612b495STsutomu Itoh err = PTR_ERR(trans); 44836217b0faSJosef Bacik goto out_clean; 448462b99540SQu Wenruo } 44853a45bb20SJeff Mahoney err = btrfs_commit_transaction(trans); 44866217b0faSJosef Bacik out_clean: 4487d2311e69SQu Wenruo ret = clean_dirty_subvols(rc); 4488d2311e69SQu Wenruo if (ret < 0 && !err) 4489d2311e69SQu Wenruo err = ret; 4490fb2d83eeSJosef Bacik out_unset: 4491fb2d83eeSJosef Bacik unset_reloc_control(rc); 44921a0afa0eSJosef Bacik free_reloc_control(rc); 44933612b495STsutomu Itoh out: 4494aca1bba6SLiu Bo if (!list_empty(&reloc_roots)) 4495aca1bba6SLiu Bo free_reloc_roots(&reloc_roots); 4496aca1bba6SLiu Bo 44975d4f98a2SYan Zheng btrfs_free_path(path); 44985d4f98a2SYan Zheng 44995d4f98a2SYan Zheng if (err == 0) { 45005d4f98a2SYan Zheng /* cleanup orphan inode in data relocation tree */ 45010b246afaSJeff Mahoney fs_root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 4502932fd26dSJosef Bacik if (IS_ERR(fs_root)) { 45035d4f98a2SYan Zheng err = PTR_ERR(fs_root); 4504932fd26dSJosef Bacik } else { 450566b4ffd1SJosef Bacik err = btrfs_orphan_cleanup(fs_root); 450600246528SJosef Bacik btrfs_put_root(fs_root); 4507932fd26dSJosef Bacik } 4508932fd26dSJosef Bacik } 45095d4f98a2SYan Zheng return err; 45105d4f98a2SYan Zheng } 45115d4f98a2SYan Zheng 45125d4f98a2SYan Zheng /* 45135d4f98a2SYan Zheng * helper to add ordered checksum for data relocation. 45145d4f98a2SYan Zheng * 45155d4f98a2SYan Zheng * cloning checksum properly handles the nodatasum extents. 45165d4f98a2SYan Zheng * it also saves CPU time to re-calculate the checksum. 45175d4f98a2SYan Zheng */ 45185d4f98a2SYan Zheng int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) 45195d4f98a2SYan Zheng { 45200b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); 45215d4f98a2SYan Zheng struct btrfs_ordered_sum *sums; 45225d4f98a2SYan Zheng struct btrfs_ordered_extent *ordered; 45235d4f98a2SYan Zheng int ret; 45245d4f98a2SYan Zheng u64 disk_bytenr; 45254577b014SJosef Bacik u64 new_bytenr; 45265d4f98a2SYan Zheng LIST_HEAD(list); 45275d4f98a2SYan Zheng 45285d4f98a2SYan Zheng ordered = btrfs_lookup_ordered_extent(inode, file_pos); 4529bffe633eSOmar Sandoval BUG_ON(ordered->file_offset != file_pos || ordered->num_bytes != len); 45305d4f98a2SYan Zheng 45315d4f98a2SYan Zheng disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; 45320b246afaSJeff Mahoney ret = btrfs_lookup_csums_range(fs_info->csum_root, disk_bytenr, 4533a2de733cSArne Jansen disk_bytenr + len - 1, &list, 0); 453479787eaaSJeff Mahoney if (ret) 453579787eaaSJeff Mahoney goto out; 45365d4f98a2SYan Zheng 45375d4f98a2SYan Zheng while (!list_empty(&list)) { 45385d4f98a2SYan Zheng sums = list_entry(list.next, struct btrfs_ordered_sum, list); 45395d4f98a2SYan Zheng list_del_init(&sums->list); 45405d4f98a2SYan Zheng 45414577b014SJosef Bacik /* 45424577b014SJosef Bacik * We need to offset the new_bytenr based on where the csum is. 45434577b014SJosef Bacik * We need to do this because we will read in entire prealloc 45444577b014SJosef Bacik * extents but we may have written to say the middle of the 45454577b014SJosef Bacik * prealloc extent, so we need to make sure the csum goes with 45464577b014SJosef Bacik * the right disk offset. 45474577b014SJosef Bacik * 45484577b014SJosef Bacik * We can do this because the data reloc inode refers strictly 45494577b014SJosef Bacik * to the on disk bytes, so we don't have to worry about 45504577b014SJosef Bacik * disk_len vs real len like with real inodes since it's all 45514577b014SJosef Bacik * disk length. 45524577b014SJosef Bacik */ 4553bffe633eSOmar Sandoval new_bytenr = ordered->disk_bytenr + sums->bytenr - disk_bytenr; 45544577b014SJosef Bacik sums->bytenr = new_bytenr; 45555d4f98a2SYan Zheng 4556f9756261SNikolay Borisov btrfs_add_ordered_sum(ordered, sums); 45575d4f98a2SYan Zheng } 455879787eaaSJeff Mahoney out: 45595d4f98a2SYan Zheng btrfs_put_ordered_extent(ordered); 4560411fc6bcSAndi Kleen return ret; 45615d4f98a2SYan Zheng } 45623fd0a558SYan, Zheng 456383d4cfd4SJosef Bacik int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, 45643fd0a558SYan, Zheng struct btrfs_root *root, struct extent_buffer *buf, 45653fd0a558SYan, Zheng struct extent_buffer *cow) 45663fd0a558SYan, Zheng { 45670b246afaSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 45683fd0a558SYan, Zheng struct reloc_control *rc; 4569a26195a5SQu Wenruo struct btrfs_backref_node *node; 45703fd0a558SYan, Zheng int first_cow = 0; 45713fd0a558SYan, Zheng int level; 457283d4cfd4SJosef Bacik int ret = 0; 45733fd0a558SYan, Zheng 45740b246afaSJeff Mahoney rc = fs_info->reloc_ctl; 45753fd0a558SYan, Zheng if (!rc) 457683d4cfd4SJosef Bacik return 0; 45773fd0a558SYan, Zheng 45783fd0a558SYan, Zheng BUG_ON(rc->stage == UPDATE_DATA_PTRS && 45793fd0a558SYan, Zheng root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID); 45803fd0a558SYan, Zheng 45813fd0a558SYan, Zheng level = btrfs_header_level(buf); 45823fd0a558SYan, Zheng if (btrfs_header_generation(buf) <= 45833fd0a558SYan, Zheng btrfs_root_last_snapshot(&root->root_item)) 45843fd0a558SYan, Zheng first_cow = 1; 45853fd0a558SYan, Zheng 45863fd0a558SYan, Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID && 45873fd0a558SYan, Zheng rc->create_reloc_tree) { 45883fd0a558SYan, Zheng WARN_ON(!first_cow && level == 0); 45893fd0a558SYan, Zheng 45903fd0a558SYan, Zheng node = rc->backref_cache.path[level]; 45913fd0a558SYan, Zheng BUG_ON(node->bytenr != buf->start && 45923fd0a558SYan, Zheng node->new_bytenr != buf->start); 45933fd0a558SYan, Zheng 45943fd0a558SYan, Zheng drop_node_buffer(node); 459567439dadSDavid Sterba atomic_inc(&cow->refs); 45963fd0a558SYan, Zheng node->eb = cow; 45973fd0a558SYan, Zheng node->new_bytenr = cow->start; 45983fd0a558SYan, Zheng 45993fd0a558SYan, Zheng if (!node->pending) { 46003fd0a558SYan, Zheng list_move_tail(&node->list, 46013fd0a558SYan, Zheng &rc->backref_cache.pending[level]); 46023fd0a558SYan, Zheng node->pending = 1; 46033fd0a558SYan, Zheng } 46043fd0a558SYan, Zheng 46053fd0a558SYan, Zheng if (first_cow) 46069569cc20SQu Wenruo mark_block_processed(rc, node); 46073fd0a558SYan, Zheng 46083fd0a558SYan, Zheng if (first_cow && level > 0) 46093fd0a558SYan, Zheng rc->nodes_relocated += buf->len; 46103fd0a558SYan, Zheng } 46113fd0a558SYan, Zheng 461283d4cfd4SJosef Bacik if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) 46133fd0a558SYan, Zheng ret = replace_file_extents(trans, rc, root, cow); 461483d4cfd4SJosef Bacik return ret; 46153fd0a558SYan, Zheng } 46163fd0a558SYan, Zheng 46173fd0a558SYan, Zheng /* 46183fd0a558SYan, Zheng * called before creating snapshot. it calculates metadata reservation 461901327610SNicholas D Steeves * required for relocating tree blocks in the snapshot 46203fd0a558SYan, Zheng */ 4621147d256eSZhaolei void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending, 46223fd0a558SYan, Zheng u64 *bytes_to_reserve) 46233fd0a558SYan, Zheng { 462410995c04SQu Wenruo struct btrfs_root *root = pending->root; 462510995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 46263fd0a558SYan, Zheng 46276282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 46283fd0a558SYan, Zheng return; 46293fd0a558SYan, Zheng 46303fd0a558SYan, Zheng if (!rc->merge_reloc_tree) 46313fd0a558SYan, Zheng return; 46323fd0a558SYan, Zheng 46333fd0a558SYan, Zheng root = root->reloc_root; 46343fd0a558SYan, Zheng BUG_ON(btrfs_root_refs(&root->root_item) == 0); 46353fd0a558SYan, Zheng /* 46363fd0a558SYan, Zheng * relocation is in the stage of merging trees. the space 46373fd0a558SYan, Zheng * used by merging a reloc tree is twice the size of 46383fd0a558SYan, Zheng * relocated tree nodes in the worst case. half for cowing 46393fd0a558SYan, Zheng * the reloc tree, half for cowing the fs tree. the space 46403fd0a558SYan, Zheng * used by cowing the reloc tree will be freed after the 46413fd0a558SYan, Zheng * tree is dropped. if we create snapshot, cowing the fs 46423fd0a558SYan, Zheng * tree may use more space than it frees. so we need 46433fd0a558SYan, Zheng * reserve extra space. 46443fd0a558SYan, Zheng */ 46453fd0a558SYan, Zheng *bytes_to_reserve += rc->nodes_relocated; 46463fd0a558SYan, Zheng } 46473fd0a558SYan, Zheng 46483fd0a558SYan, Zheng /* 46493fd0a558SYan, Zheng * called after snapshot is created. migrate block reservation 46503fd0a558SYan, Zheng * and create reloc root for the newly created snapshot 4651f44deb74SJosef Bacik * 4652f44deb74SJosef Bacik * This is similar to btrfs_init_reloc_root(), we come out of here with two 4653f44deb74SJosef Bacik * references held on the reloc_root, one for root->reloc_root and one for 4654f44deb74SJosef Bacik * rc->reloc_roots. 46553fd0a558SYan, Zheng */ 465649b25e05SJeff Mahoney int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, 46573fd0a558SYan, Zheng struct btrfs_pending_snapshot *pending) 46583fd0a558SYan, Zheng { 46593fd0a558SYan, Zheng struct btrfs_root *root = pending->root; 46603fd0a558SYan, Zheng struct btrfs_root *reloc_root; 46613fd0a558SYan, Zheng struct btrfs_root *new_root; 466210995c04SQu Wenruo struct reloc_control *rc = root->fs_info->reloc_ctl; 46633fd0a558SYan, Zheng int ret; 46643fd0a558SYan, Zheng 46656282675eSQu Wenruo if (!rc || !have_reloc_root(root)) 466649b25e05SJeff Mahoney return 0; 46673fd0a558SYan, Zheng 46683fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 46693fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated; 46703fd0a558SYan, Zheng 46713fd0a558SYan, Zheng if (rc->merge_reloc_tree) { 46723fd0a558SYan, Zheng ret = btrfs_block_rsv_migrate(&pending->block_rsv, 46733fd0a558SYan, Zheng rc->block_rsv, 46743a584174SLu Fengqi rc->nodes_relocated, true); 467549b25e05SJeff Mahoney if (ret) 467649b25e05SJeff Mahoney return ret; 46773fd0a558SYan, Zheng } 46783fd0a558SYan, Zheng 46793fd0a558SYan, Zheng new_root = pending->snap; 46803fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root->reloc_root, 46813fd0a558SYan, Zheng new_root->root_key.objectid); 468249b25e05SJeff Mahoney if (IS_ERR(reloc_root)) 468349b25e05SJeff Mahoney return PTR_ERR(reloc_root); 46843fd0a558SYan, Zheng 4685ffd7b339SJeff Mahoney ret = __add_reloc_root(reloc_root); 4686ffd7b339SJeff Mahoney BUG_ON(ret < 0); 4687f44deb74SJosef Bacik new_root->reloc_root = btrfs_grab_root(reloc_root); 46883fd0a558SYan, Zheng 468949b25e05SJeff Mahoney if (rc->create_reloc_tree) 46903fd0a558SYan, Zheng ret = clone_backref_node(trans, rc, root, reloc_root); 469149b25e05SJeff Mahoney return ret; 46923fd0a558SYan, Zheng } 4693