15d4f98a2SYan Zheng /* 25d4f98a2SYan Zheng * Copyright (C) 2009 Oracle. All rights reserved. 35d4f98a2SYan Zheng * 45d4f98a2SYan Zheng * This program is free software; you can redistribute it and/or 55d4f98a2SYan Zheng * modify it under the terms of the GNU General Public 65d4f98a2SYan Zheng * License v2 as published by the Free Software Foundation. 75d4f98a2SYan Zheng * 85d4f98a2SYan Zheng * This program is distributed in the hope that it will be useful, 95d4f98a2SYan Zheng * but WITHOUT ANY WARRANTY; without even the implied warranty of 105d4f98a2SYan Zheng * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 115d4f98a2SYan Zheng * General Public License for more details. 125d4f98a2SYan Zheng * 135d4f98a2SYan Zheng * You should have received a copy of the GNU General Public 145d4f98a2SYan Zheng * License along with this program; if not, write to the 155d4f98a2SYan Zheng * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 165d4f98a2SYan Zheng * Boston, MA 021110-1307, USA. 175d4f98a2SYan Zheng */ 185d4f98a2SYan Zheng 195d4f98a2SYan Zheng #include <linux/sched.h> 205d4f98a2SYan Zheng #include <linux/pagemap.h> 215d4f98a2SYan Zheng #include <linux/writeback.h> 225d4f98a2SYan Zheng #include <linux/blkdev.h> 235d4f98a2SYan Zheng #include <linux/rbtree.h> 245a0e3ad6STejun Heo #include <linux/slab.h> 255d4f98a2SYan Zheng #include "ctree.h" 265d4f98a2SYan Zheng #include "disk-io.h" 275d4f98a2SYan Zheng #include "transaction.h" 285d4f98a2SYan Zheng #include "volumes.h" 295d4f98a2SYan Zheng #include "locking.h" 305d4f98a2SYan Zheng #include "btrfs_inode.h" 315d4f98a2SYan Zheng #include "async-thread.h" 320af3d00bSJosef Bacik #include "free-space-cache.h" 335d4f98a2SYan Zheng 345d4f98a2SYan Zheng /* 355d4f98a2SYan Zheng * backref_node, mapping_node and tree_block start with this 365d4f98a2SYan Zheng */ 375d4f98a2SYan Zheng struct tree_entry { 385d4f98a2SYan Zheng struct rb_node rb_node; 395d4f98a2SYan Zheng u64 bytenr; 405d4f98a2SYan Zheng }; 415d4f98a2SYan Zheng 425d4f98a2SYan Zheng /* 435d4f98a2SYan Zheng * present a tree block in the backref cache 445d4f98a2SYan Zheng */ 455d4f98a2SYan Zheng struct backref_node { 465d4f98a2SYan Zheng struct rb_node rb_node; 475d4f98a2SYan Zheng u64 bytenr; 483fd0a558SYan, Zheng 493fd0a558SYan, Zheng u64 new_bytenr; 503fd0a558SYan, Zheng /* objectid of tree block owner, can be not uptodate */ 515d4f98a2SYan Zheng u64 owner; 523fd0a558SYan, Zheng /* link to pending, changed or detached list */ 533fd0a558SYan, Zheng struct list_head list; 545d4f98a2SYan Zheng /* list of upper level blocks reference this block */ 555d4f98a2SYan Zheng struct list_head upper; 565d4f98a2SYan Zheng /* list of child blocks in the cache */ 575d4f98a2SYan Zheng struct list_head lower; 585d4f98a2SYan Zheng /* NULL if this node is not tree root */ 595d4f98a2SYan Zheng struct btrfs_root *root; 605d4f98a2SYan Zheng /* extent buffer got by COW the block */ 615d4f98a2SYan Zheng struct extent_buffer *eb; 625d4f98a2SYan Zheng /* level of tree block */ 635d4f98a2SYan Zheng unsigned int level:8; 643fd0a558SYan, Zheng /* is the block in non-reference counted tree */ 653fd0a558SYan, Zheng unsigned int cowonly:1; 663fd0a558SYan, Zheng /* 1 if no child node in the cache */ 675d4f98a2SYan Zheng unsigned int lowest:1; 685d4f98a2SYan Zheng /* is the extent buffer locked */ 695d4f98a2SYan Zheng unsigned int locked:1; 705d4f98a2SYan Zheng /* has the block been processed */ 715d4f98a2SYan Zheng unsigned int processed:1; 725d4f98a2SYan Zheng /* have backrefs of this block been checked */ 735d4f98a2SYan Zheng unsigned int checked:1; 743fd0a558SYan, Zheng /* 753fd0a558SYan, Zheng * 1 if corresponding block has been cowed but some upper 763fd0a558SYan, Zheng * level block pointers may not point to the new location 773fd0a558SYan, Zheng */ 783fd0a558SYan, Zheng unsigned int pending:1; 793fd0a558SYan, Zheng /* 803fd0a558SYan, Zheng * 1 if the backref node isn't connected to any other 813fd0a558SYan, Zheng * backref node. 823fd0a558SYan, Zheng */ 833fd0a558SYan, Zheng unsigned int detached:1; 845d4f98a2SYan Zheng }; 855d4f98a2SYan Zheng 865d4f98a2SYan Zheng /* 875d4f98a2SYan Zheng * present a block pointer in the backref cache 885d4f98a2SYan Zheng */ 895d4f98a2SYan Zheng struct backref_edge { 905d4f98a2SYan Zheng struct list_head list[2]; 915d4f98a2SYan Zheng struct backref_node *node[2]; 925d4f98a2SYan Zheng }; 935d4f98a2SYan Zheng 945d4f98a2SYan Zheng #define LOWER 0 955d4f98a2SYan Zheng #define UPPER 1 965d4f98a2SYan Zheng 975d4f98a2SYan Zheng struct backref_cache { 985d4f98a2SYan Zheng /* red black tree of all backref nodes in the cache */ 995d4f98a2SYan Zheng struct rb_root rb_root; 1003fd0a558SYan, Zheng /* for passing backref nodes to btrfs_reloc_cow_block */ 1013fd0a558SYan, Zheng struct backref_node *path[BTRFS_MAX_LEVEL]; 1023fd0a558SYan, Zheng /* 1033fd0a558SYan, Zheng * list of blocks that have been cowed but some block 1043fd0a558SYan, Zheng * pointers in upper level blocks may not reflect the 1053fd0a558SYan, Zheng * new location 1063fd0a558SYan, Zheng */ 1075d4f98a2SYan Zheng struct list_head pending[BTRFS_MAX_LEVEL]; 1083fd0a558SYan, Zheng /* list of backref nodes with no child node */ 1093fd0a558SYan, Zheng struct list_head leaves; 1103fd0a558SYan, Zheng /* list of blocks that have been cowed in current transaction */ 1113fd0a558SYan, Zheng struct list_head changed; 1123fd0a558SYan, Zheng /* list of detached backref node. */ 1133fd0a558SYan, Zheng struct list_head detached; 1143fd0a558SYan, Zheng 1153fd0a558SYan, Zheng u64 last_trans; 1163fd0a558SYan, Zheng 1173fd0a558SYan, Zheng int nr_nodes; 1183fd0a558SYan, Zheng int nr_edges; 1195d4f98a2SYan Zheng }; 1205d4f98a2SYan Zheng 1215d4f98a2SYan Zheng /* 1225d4f98a2SYan Zheng * map address of tree root to tree 1235d4f98a2SYan Zheng */ 1245d4f98a2SYan Zheng struct mapping_node { 1255d4f98a2SYan Zheng struct rb_node rb_node; 1265d4f98a2SYan Zheng u64 bytenr; 1275d4f98a2SYan Zheng void *data; 1285d4f98a2SYan Zheng }; 1295d4f98a2SYan Zheng 1305d4f98a2SYan Zheng struct mapping_tree { 1315d4f98a2SYan Zheng struct rb_root rb_root; 1325d4f98a2SYan Zheng spinlock_t lock; 1335d4f98a2SYan Zheng }; 1345d4f98a2SYan Zheng 1355d4f98a2SYan Zheng /* 1365d4f98a2SYan Zheng * present a tree block to process 1375d4f98a2SYan Zheng */ 1385d4f98a2SYan Zheng struct tree_block { 1395d4f98a2SYan Zheng struct rb_node rb_node; 1405d4f98a2SYan Zheng u64 bytenr; 1415d4f98a2SYan Zheng struct btrfs_key key; 1425d4f98a2SYan Zheng unsigned int level:8; 1435d4f98a2SYan Zheng unsigned int key_ready:1; 1445d4f98a2SYan Zheng }; 1455d4f98a2SYan Zheng 1460257bb82SYan, Zheng #define MAX_EXTENTS 128 1470257bb82SYan, Zheng 1480257bb82SYan, Zheng struct file_extent_cluster { 1490257bb82SYan, Zheng u64 start; 1500257bb82SYan, Zheng u64 end; 1510257bb82SYan, Zheng u64 boundary[MAX_EXTENTS]; 1520257bb82SYan, Zheng unsigned int nr; 1530257bb82SYan, Zheng }; 1540257bb82SYan, Zheng 1555d4f98a2SYan Zheng struct reloc_control { 1565d4f98a2SYan Zheng /* block group to relocate */ 1575d4f98a2SYan Zheng struct btrfs_block_group_cache *block_group; 1585d4f98a2SYan Zheng /* extent tree */ 1595d4f98a2SYan Zheng struct btrfs_root *extent_root; 1605d4f98a2SYan Zheng /* inode for moving data */ 1615d4f98a2SYan Zheng struct inode *data_inode; 1623fd0a558SYan, Zheng 1633fd0a558SYan, Zheng struct btrfs_block_rsv *block_rsv; 1643fd0a558SYan, Zheng 1653fd0a558SYan, Zheng struct backref_cache backref_cache; 1663fd0a558SYan, Zheng 1673fd0a558SYan, Zheng struct file_extent_cluster cluster; 1685d4f98a2SYan Zheng /* tree blocks have been processed */ 1695d4f98a2SYan Zheng struct extent_io_tree processed_blocks; 1705d4f98a2SYan Zheng /* map start of tree root to corresponding reloc tree */ 1715d4f98a2SYan Zheng struct mapping_tree reloc_root_tree; 1725d4f98a2SYan Zheng /* list of reloc trees */ 1735d4f98a2SYan Zheng struct list_head reloc_roots; 1743fd0a558SYan, Zheng /* size of metadata reservation for merging reloc trees */ 1753fd0a558SYan, Zheng u64 merging_rsv_size; 1763fd0a558SYan, Zheng /* size of relocated tree nodes */ 1773fd0a558SYan, Zheng u64 nodes_relocated; 1783fd0a558SYan, Zheng 1795d4f98a2SYan Zheng u64 search_start; 1805d4f98a2SYan Zheng u64 extents_found; 1813fd0a558SYan, Zheng 1823fd0a558SYan, Zheng unsigned int stage:8; 1833fd0a558SYan, Zheng unsigned int create_reloc_tree:1; 1843fd0a558SYan, Zheng unsigned int merge_reloc_tree:1; 1855d4f98a2SYan Zheng unsigned int found_file_extent:1; 1863fd0a558SYan, Zheng unsigned int commit_transaction:1; 1875d4f98a2SYan Zheng }; 1885d4f98a2SYan Zheng 1895d4f98a2SYan Zheng /* stages of data relocation */ 1905d4f98a2SYan Zheng #define MOVE_DATA_EXTENTS 0 1915d4f98a2SYan Zheng #define UPDATE_DATA_PTRS 1 1925d4f98a2SYan Zheng 1933fd0a558SYan, Zheng static void remove_backref_node(struct backref_cache *cache, 1943fd0a558SYan, Zheng struct backref_node *node); 1953fd0a558SYan, Zheng static void __mark_block_processed(struct reloc_control *rc, 1963fd0a558SYan, Zheng struct backref_node *node); 1975d4f98a2SYan Zheng 1985d4f98a2SYan Zheng static void mapping_tree_init(struct mapping_tree *tree) 1995d4f98a2SYan Zheng { 2006bef4d31SEric Paris tree->rb_root = RB_ROOT; 2015d4f98a2SYan Zheng spin_lock_init(&tree->lock); 2025d4f98a2SYan Zheng } 2035d4f98a2SYan Zheng 2045d4f98a2SYan Zheng static void backref_cache_init(struct backref_cache *cache) 2055d4f98a2SYan Zheng { 2065d4f98a2SYan Zheng int i; 2076bef4d31SEric Paris cache->rb_root = RB_ROOT; 2085d4f98a2SYan Zheng for (i = 0; i < BTRFS_MAX_LEVEL; i++) 2095d4f98a2SYan Zheng INIT_LIST_HEAD(&cache->pending[i]); 2103fd0a558SYan, Zheng INIT_LIST_HEAD(&cache->changed); 2113fd0a558SYan, Zheng INIT_LIST_HEAD(&cache->detached); 2123fd0a558SYan, Zheng INIT_LIST_HEAD(&cache->leaves); 2135d4f98a2SYan Zheng } 2145d4f98a2SYan Zheng 2153fd0a558SYan, Zheng static void backref_cache_cleanup(struct backref_cache *cache) 2165d4f98a2SYan Zheng { 2173fd0a558SYan, Zheng struct backref_node *node; 2183fd0a558SYan, Zheng int i; 2193fd0a558SYan, Zheng 2203fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 2213fd0a558SYan, Zheng node = list_entry(cache->detached.next, 2223fd0a558SYan, Zheng struct backref_node, list); 2233fd0a558SYan, Zheng remove_backref_node(cache, node); 2243fd0a558SYan, Zheng } 2253fd0a558SYan, Zheng 2263fd0a558SYan, Zheng while (!list_empty(&cache->leaves)) { 2273fd0a558SYan, Zheng node = list_entry(cache->leaves.next, 2283fd0a558SYan, Zheng struct backref_node, lower); 2293fd0a558SYan, Zheng remove_backref_node(cache, node); 2303fd0a558SYan, Zheng } 2313fd0a558SYan, Zheng 2323fd0a558SYan, Zheng cache->last_trans = 0; 2333fd0a558SYan, Zheng 2343fd0a558SYan, Zheng for (i = 0; i < BTRFS_MAX_LEVEL; i++) 2353fd0a558SYan, Zheng BUG_ON(!list_empty(&cache->pending[i])); 2363fd0a558SYan, Zheng BUG_ON(!list_empty(&cache->changed)); 2373fd0a558SYan, Zheng BUG_ON(!list_empty(&cache->detached)); 2383fd0a558SYan, Zheng BUG_ON(!RB_EMPTY_ROOT(&cache->rb_root)); 2393fd0a558SYan, Zheng BUG_ON(cache->nr_nodes); 2403fd0a558SYan, Zheng BUG_ON(cache->nr_edges); 2413fd0a558SYan, Zheng } 2423fd0a558SYan, Zheng 2433fd0a558SYan, Zheng static struct backref_node *alloc_backref_node(struct backref_cache *cache) 2443fd0a558SYan, Zheng { 2453fd0a558SYan, Zheng struct backref_node *node; 2463fd0a558SYan, Zheng 2473fd0a558SYan, Zheng node = kzalloc(sizeof(*node), GFP_NOFS); 2483fd0a558SYan, Zheng if (node) { 2493fd0a558SYan, Zheng INIT_LIST_HEAD(&node->list); 2505d4f98a2SYan Zheng INIT_LIST_HEAD(&node->upper); 2515d4f98a2SYan Zheng INIT_LIST_HEAD(&node->lower); 2525d4f98a2SYan Zheng RB_CLEAR_NODE(&node->rb_node); 2533fd0a558SYan, Zheng cache->nr_nodes++; 2543fd0a558SYan, Zheng } 2553fd0a558SYan, Zheng return node; 2563fd0a558SYan, Zheng } 2573fd0a558SYan, Zheng 2583fd0a558SYan, Zheng static void free_backref_node(struct backref_cache *cache, 2593fd0a558SYan, Zheng struct backref_node *node) 2603fd0a558SYan, Zheng { 2613fd0a558SYan, Zheng if (node) { 2623fd0a558SYan, Zheng cache->nr_nodes--; 2633fd0a558SYan, Zheng kfree(node); 2643fd0a558SYan, Zheng } 2653fd0a558SYan, Zheng } 2663fd0a558SYan, Zheng 2673fd0a558SYan, Zheng static struct backref_edge *alloc_backref_edge(struct backref_cache *cache) 2683fd0a558SYan, Zheng { 2693fd0a558SYan, Zheng struct backref_edge *edge; 2703fd0a558SYan, Zheng 2713fd0a558SYan, Zheng edge = kzalloc(sizeof(*edge), GFP_NOFS); 2723fd0a558SYan, Zheng if (edge) 2733fd0a558SYan, Zheng cache->nr_edges++; 2743fd0a558SYan, Zheng return edge; 2753fd0a558SYan, Zheng } 2763fd0a558SYan, Zheng 2773fd0a558SYan, Zheng static void free_backref_edge(struct backref_cache *cache, 2783fd0a558SYan, Zheng struct backref_edge *edge) 2793fd0a558SYan, Zheng { 2803fd0a558SYan, Zheng if (edge) { 2813fd0a558SYan, Zheng cache->nr_edges--; 2823fd0a558SYan, Zheng kfree(edge); 2833fd0a558SYan, Zheng } 2845d4f98a2SYan Zheng } 2855d4f98a2SYan Zheng 2865d4f98a2SYan Zheng static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr, 2875d4f98a2SYan Zheng struct rb_node *node) 2885d4f98a2SYan Zheng { 2895d4f98a2SYan Zheng struct rb_node **p = &root->rb_node; 2905d4f98a2SYan Zheng struct rb_node *parent = NULL; 2915d4f98a2SYan Zheng struct tree_entry *entry; 2925d4f98a2SYan Zheng 2935d4f98a2SYan Zheng while (*p) { 2945d4f98a2SYan Zheng parent = *p; 2955d4f98a2SYan Zheng entry = rb_entry(parent, struct tree_entry, rb_node); 2965d4f98a2SYan Zheng 2975d4f98a2SYan Zheng if (bytenr < entry->bytenr) 2985d4f98a2SYan Zheng p = &(*p)->rb_left; 2995d4f98a2SYan Zheng else if (bytenr > entry->bytenr) 3005d4f98a2SYan Zheng p = &(*p)->rb_right; 3015d4f98a2SYan Zheng else 3025d4f98a2SYan Zheng return parent; 3035d4f98a2SYan Zheng } 3045d4f98a2SYan Zheng 3055d4f98a2SYan Zheng rb_link_node(node, parent, p); 3065d4f98a2SYan Zheng rb_insert_color(node, root); 3075d4f98a2SYan Zheng return NULL; 3085d4f98a2SYan Zheng } 3095d4f98a2SYan Zheng 3105d4f98a2SYan Zheng static struct rb_node *tree_search(struct rb_root *root, u64 bytenr) 3115d4f98a2SYan Zheng { 3125d4f98a2SYan Zheng struct rb_node *n = root->rb_node; 3135d4f98a2SYan Zheng struct tree_entry *entry; 3145d4f98a2SYan Zheng 3155d4f98a2SYan Zheng while (n) { 3165d4f98a2SYan Zheng entry = rb_entry(n, struct tree_entry, rb_node); 3175d4f98a2SYan Zheng 3185d4f98a2SYan Zheng if (bytenr < entry->bytenr) 3195d4f98a2SYan Zheng n = n->rb_left; 3205d4f98a2SYan Zheng else if (bytenr > entry->bytenr) 3215d4f98a2SYan Zheng n = n->rb_right; 3225d4f98a2SYan Zheng else 3235d4f98a2SYan Zheng return n; 3245d4f98a2SYan Zheng } 3255d4f98a2SYan Zheng return NULL; 3265d4f98a2SYan Zheng } 3275d4f98a2SYan Zheng 3285d4f98a2SYan Zheng /* 3295d4f98a2SYan Zheng * walk up backref nodes until reach node presents tree root 3305d4f98a2SYan Zheng */ 3315d4f98a2SYan Zheng static struct backref_node *walk_up_backref(struct backref_node *node, 3325d4f98a2SYan Zheng struct backref_edge *edges[], 3335d4f98a2SYan Zheng int *index) 3345d4f98a2SYan Zheng { 3355d4f98a2SYan Zheng struct backref_edge *edge; 3365d4f98a2SYan Zheng int idx = *index; 3375d4f98a2SYan Zheng 3385d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 3395d4f98a2SYan Zheng edge = list_entry(node->upper.next, 3405d4f98a2SYan Zheng struct backref_edge, list[LOWER]); 3415d4f98a2SYan Zheng edges[idx++] = edge; 3425d4f98a2SYan Zheng node = edge->node[UPPER]; 3435d4f98a2SYan Zheng } 3443fd0a558SYan, Zheng BUG_ON(node->detached); 3455d4f98a2SYan Zheng *index = idx; 3465d4f98a2SYan Zheng return node; 3475d4f98a2SYan Zheng } 3485d4f98a2SYan Zheng 3495d4f98a2SYan Zheng /* 3505d4f98a2SYan Zheng * walk down backref nodes to find start of next reference path 3515d4f98a2SYan Zheng */ 3525d4f98a2SYan Zheng static struct backref_node *walk_down_backref(struct backref_edge *edges[], 3535d4f98a2SYan Zheng int *index) 3545d4f98a2SYan Zheng { 3555d4f98a2SYan Zheng struct backref_edge *edge; 3565d4f98a2SYan Zheng struct backref_node *lower; 3575d4f98a2SYan Zheng int idx = *index; 3585d4f98a2SYan Zheng 3595d4f98a2SYan Zheng while (idx > 0) { 3605d4f98a2SYan Zheng edge = edges[idx - 1]; 3615d4f98a2SYan Zheng lower = edge->node[LOWER]; 3625d4f98a2SYan Zheng if (list_is_last(&edge->list[LOWER], &lower->upper)) { 3635d4f98a2SYan Zheng idx--; 3645d4f98a2SYan Zheng continue; 3655d4f98a2SYan Zheng } 3665d4f98a2SYan Zheng edge = list_entry(edge->list[LOWER].next, 3675d4f98a2SYan Zheng struct backref_edge, list[LOWER]); 3685d4f98a2SYan Zheng edges[idx - 1] = edge; 3695d4f98a2SYan Zheng *index = idx; 3705d4f98a2SYan Zheng return edge->node[UPPER]; 3715d4f98a2SYan Zheng } 3725d4f98a2SYan Zheng *index = 0; 3735d4f98a2SYan Zheng return NULL; 3745d4f98a2SYan Zheng } 3755d4f98a2SYan Zheng 3763fd0a558SYan, Zheng static void unlock_node_buffer(struct backref_node *node) 3775d4f98a2SYan Zheng { 3785d4f98a2SYan Zheng if (node->locked) { 3795d4f98a2SYan Zheng btrfs_tree_unlock(node->eb); 3805d4f98a2SYan Zheng node->locked = 0; 3815d4f98a2SYan Zheng } 3823fd0a558SYan, Zheng } 3833fd0a558SYan, Zheng 3843fd0a558SYan, Zheng static void drop_node_buffer(struct backref_node *node) 3853fd0a558SYan, Zheng { 3863fd0a558SYan, Zheng if (node->eb) { 3873fd0a558SYan, Zheng unlock_node_buffer(node); 3885d4f98a2SYan Zheng free_extent_buffer(node->eb); 3895d4f98a2SYan Zheng node->eb = NULL; 3905d4f98a2SYan Zheng } 3915d4f98a2SYan Zheng } 3925d4f98a2SYan Zheng 3935d4f98a2SYan Zheng static void drop_backref_node(struct backref_cache *tree, 3945d4f98a2SYan Zheng struct backref_node *node) 3955d4f98a2SYan Zheng { 3965d4f98a2SYan Zheng BUG_ON(!list_empty(&node->upper)); 3975d4f98a2SYan Zheng 3985d4f98a2SYan Zheng drop_node_buffer(node); 3993fd0a558SYan, Zheng list_del(&node->list); 4005d4f98a2SYan Zheng list_del(&node->lower); 4013fd0a558SYan, Zheng if (!RB_EMPTY_NODE(&node->rb_node)) 4025d4f98a2SYan Zheng rb_erase(&node->rb_node, &tree->rb_root); 4033fd0a558SYan, Zheng free_backref_node(tree, node); 4045d4f98a2SYan Zheng } 4055d4f98a2SYan Zheng 4065d4f98a2SYan Zheng /* 4075d4f98a2SYan Zheng * remove a backref node from the backref cache 4085d4f98a2SYan Zheng */ 4095d4f98a2SYan Zheng static void remove_backref_node(struct backref_cache *cache, 4105d4f98a2SYan Zheng struct backref_node *node) 4115d4f98a2SYan Zheng { 4125d4f98a2SYan Zheng struct backref_node *upper; 4135d4f98a2SYan Zheng struct backref_edge *edge; 4145d4f98a2SYan Zheng 4155d4f98a2SYan Zheng if (!node) 4165d4f98a2SYan Zheng return; 4175d4f98a2SYan Zheng 4183fd0a558SYan, Zheng BUG_ON(!node->lowest && !node->detached); 4195d4f98a2SYan Zheng while (!list_empty(&node->upper)) { 4205d4f98a2SYan Zheng edge = list_entry(node->upper.next, struct backref_edge, 4215d4f98a2SYan Zheng list[LOWER]); 4225d4f98a2SYan Zheng upper = edge->node[UPPER]; 4235d4f98a2SYan Zheng list_del(&edge->list[LOWER]); 4245d4f98a2SYan Zheng list_del(&edge->list[UPPER]); 4253fd0a558SYan, Zheng free_backref_edge(cache, edge); 4263fd0a558SYan, Zheng 4273fd0a558SYan, Zheng if (RB_EMPTY_NODE(&upper->rb_node)) { 4283fd0a558SYan, Zheng BUG_ON(!list_empty(&node->upper)); 4293fd0a558SYan, Zheng drop_backref_node(cache, node); 4303fd0a558SYan, Zheng node = upper; 4313fd0a558SYan, Zheng node->lowest = 1; 4323fd0a558SYan, Zheng continue; 4333fd0a558SYan, Zheng } 4345d4f98a2SYan Zheng /* 4353fd0a558SYan, Zheng * add the node to leaf node list if no other 4365d4f98a2SYan Zheng * child block cached. 4375d4f98a2SYan Zheng */ 4385d4f98a2SYan Zheng if (list_empty(&upper->lower)) { 4393fd0a558SYan, Zheng list_add_tail(&upper->lower, &cache->leaves); 4405d4f98a2SYan Zheng upper->lowest = 1; 4415d4f98a2SYan Zheng } 4425d4f98a2SYan Zheng } 4433fd0a558SYan, Zheng 4445d4f98a2SYan Zheng drop_backref_node(cache, node); 4455d4f98a2SYan Zheng } 4465d4f98a2SYan Zheng 4473fd0a558SYan, Zheng static void update_backref_node(struct backref_cache *cache, 4483fd0a558SYan, Zheng struct backref_node *node, u64 bytenr) 4493fd0a558SYan, Zheng { 4503fd0a558SYan, Zheng struct rb_node *rb_node; 4513fd0a558SYan, Zheng rb_erase(&node->rb_node, &cache->rb_root); 4523fd0a558SYan, Zheng node->bytenr = bytenr; 4533fd0a558SYan, Zheng rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node); 4543fd0a558SYan, Zheng BUG_ON(rb_node); 4553fd0a558SYan, Zheng } 4563fd0a558SYan, Zheng 4573fd0a558SYan, Zheng /* 4583fd0a558SYan, Zheng * update backref cache after a transaction commit 4593fd0a558SYan, Zheng */ 4603fd0a558SYan, Zheng static int update_backref_cache(struct btrfs_trans_handle *trans, 4613fd0a558SYan, Zheng struct backref_cache *cache) 4623fd0a558SYan, Zheng { 4633fd0a558SYan, Zheng struct backref_node *node; 4643fd0a558SYan, Zheng int level = 0; 4653fd0a558SYan, Zheng 4663fd0a558SYan, Zheng if (cache->last_trans == 0) { 4673fd0a558SYan, Zheng cache->last_trans = trans->transid; 4683fd0a558SYan, Zheng return 0; 4693fd0a558SYan, Zheng } 4703fd0a558SYan, Zheng 4713fd0a558SYan, Zheng if (cache->last_trans == trans->transid) 4723fd0a558SYan, Zheng return 0; 4733fd0a558SYan, Zheng 4743fd0a558SYan, Zheng /* 4753fd0a558SYan, Zheng * detached nodes are used to avoid unnecessary backref 4763fd0a558SYan, Zheng * lookup. transaction commit changes the extent tree. 4773fd0a558SYan, Zheng * so the detached nodes are no longer useful. 4783fd0a558SYan, Zheng */ 4793fd0a558SYan, Zheng while (!list_empty(&cache->detached)) { 4803fd0a558SYan, Zheng node = list_entry(cache->detached.next, 4813fd0a558SYan, Zheng struct backref_node, list); 4823fd0a558SYan, Zheng remove_backref_node(cache, node); 4833fd0a558SYan, Zheng } 4843fd0a558SYan, Zheng 4853fd0a558SYan, Zheng while (!list_empty(&cache->changed)) { 4863fd0a558SYan, Zheng node = list_entry(cache->changed.next, 4873fd0a558SYan, Zheng struct backref_node, list); 4883fd0a558SYan, Zheng list_del_init(&node->list); 4893fd0a558SYan, Zheng BUG_ON(node->pending); 4903fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 4913fd0a558SYan, Zheng } 4923fd0a558SYan, Zheng 4933fd0a558SYan, Zheng /* 4943fd0a558SYan, Zheng * some nodes can be left in the pending list if there were 4953fd0a558SYan, Zheng * errors during processing the pending nodes. 4963fd0a558SYan, Zheng */ 4973fd0a558SYan, Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 4983fd0a558SYan, Zheng list_for_each_entry(node, &cache->pending[level], list) { 4993fd0a558SYan, Zheng BUG_ON(!node->pending); 5003fd0a558SYan, Zheng if (node->bytenr == node->new_bytenr) 5013fd0a558SYan, Zheng continue; 5023fd0a558SYan, Zheng update_backref_node(cache, node, node->new_bytenr); 5033fd0a558SYan, Zheng } 5043fd0a558SYan, Zheng } 5053fd0a558SYan, Zheng 5063fd0a558SYan, Zheng cache->last_trans = 0; 5073fd0a558SYan, Zheng return 1; 5083fd0a558SYan, Zheng } 5093fd0a558SYan, Zheng 5103fd0a558SYan, Zheng static int should_ignore_root(struct btrfs_root *root) 5113fd0a558SYan, Zheng { 5123fd0a558SYan, Zheng struct btrfs_root *reloc_root; 5133fd0a558SYan, Zheng 5143fd0a558SYan, Zheng if (!root->ref_cows) 5153fd0a558SYan, Zheng return 0; 5163fd0a558SYan, Zheng 5173fd0a558SYan, Zheng reloc_root = root->reloc_root; 5183fd0a558SYan, Zheng if (!reloc_root) 5193fd0a558SYan, Zheng return 0; 5203fd0a558SYan, Zheng 5213fd0a558SYan, Zheng if (btrfs_root_last_snapshot(&reloc_root->root_item) == 5223fd0a558SYan, Zheng root->fs_info->running_transaction->transid - 1) 5233fd0a558SYan, Zheng return 0; 5243fd0a558SYan, Zheng /* 5253fd0a558SYan, Zheng * if there is reloc tree and it was created in previous 5263fd0a558SYan, Zheng * transaction backref lookup can find the reloc tree, 5273fd0a558SYan, Zheng * so backref node for the fs tree root is useless for 5283fd0a558SYan, Zheng * relocation. 5293fd0a558SYan, Zheng */ 5303fd0a558SYan, Zheng return 1; 5313fd0a558SYan, Zheng } 5323fd0a558SYan, Zheng 5335d4f98a2SYan Zheng /* 5345d4f98a2SYan Zheng * find reloc tree by address of tree root 5355d4f98a2SYan Zheng */ 5365d4f98a2SYan Zheng static struct btrfs_root *find_reloc_root(struct reloc_control *rc, 5375d4f98a2SYan Zheng u64 bytenr) 5385d4f98a2SYan Zheng { 5395d4f98a2SYan Zheng struct rb_node *rb_node; 5405d4f98a2SYan Zheng struct mapping_node *node; 5415d4f98a2SYan Zheng struct btrfs_root *root = NULL; 5425d4f98a2SYan Zheng 5435d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 5445d4f98a2SYan Zheng rb_node = tree_search(&rc->reloc_root_tree.rb_root, bytenr); 5455d4f98a2SYan Zheng if (rb_node) { 5465d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 5475d4f98a2SYan Zheng root = (struct btrfs_root *)node->data; 5485d4f98a2SYan Zheng } 5495d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 5505d4f98a2SYan Zheng return root; 5515d4f98a2SYan Zheng } 5525d4f98a2SYan Zheng 5535d4f98a2SYan Zheng static int is_cowonly_root(u64 root_objectid) 5545d4f98a2SYan Zheng { 5555d4f98a2SYan Zheng if (root_objectid == BTRFS_ROOT_TREE_OBJECTID || 5565d4f98a2SYan Zheng root_objectid == BTRFS_EXTENT_TREE_OBJECTID || 5575d4f98a2SYan Zheng root_objectid == BTRFS_CHUNK_TREE_OBJECTID || 5585d4f98a2SYan Zheng root_objectid == BTRFS_DEV_TREE_OBJECTID || 5595d4f98a2SYan Zheng root_objectid == BTRFS_TREE_LOG_OBJECTID || 5605d4f98a2SYan Zheng root_objectid == BTRFS_CSUM_TREE_OBJECTID) 5615d4f98a2SYan Zheng return 1; 5625d4f98a2SYan Zheng return 0; 5635d4f98a2SYan Zheng } 5645d4f98a2SYan Zheng 5655d4f98a2SYan Zheng static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, 5665d4f98a2SYan Zheng u64 root_objectid) 5675d4f98a2SYan Zheng { 5685d4f98a2SYan Zheng struct btrfs_key key; 5695d4f98a2SYan Zheng 5705d4f98a2SYan Zheng key.objectid = root_objectid; 5715d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 5725d4f98a2SYan Zheng if (is_cowonly_root(root_objectid)) 5735d4f98a2SYan Zheng key.offset = 0; 5745d4f98a2SYan Zheng else 5755d4f98a2SYan Zheng key.offset = (u64)-1; 5765d4f98a2SYan Zheng 5775d4f98a2SYan Zheng return btrfs_read_fs_root_no_name(fs_info, &key); 5785d4f98a2SYan Zheng } 5795d4f98a2SYan Zheng 5805d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 5815d4f98a2SYan Zheng static noinline_for_stack 5825d4f98a2SYan Zheng struct btrfs_root *find_tree_root(struct reloc_control *rc, 5835d4f98a2SYan Zheng struct extent_buffer *leaf, 5845d4f98a2SYan Zheng struct btrfs_extent_ref_v0 *ref0) 5855d4f98a2SYan Zheng { 5865d4f98a2SYan Zheng struct btrfs_root *root; 5875d4f98a2SYan Zheng u64 root_objectid = btrfs_ref_root_v0(leaf, ref0); 5885d4f98a2SYan Zheng u64 generation = btrfs_ref_generation_v0(leaf, ref0); 5895d4f98a2SYan Zheng 5905d4f98a2SYan Zheng BUG_ON(root_objectid == BTRFS_TREE_RELOC_OBJECTID); 5915d4f98a2SYan Zheng 5925d4f98a2SYan Zheng root = read_fs_root(rc->extent_root->fs_info, root_objectid); 5935d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 5945d4f98a2SYan Zheng 5955d4f98a2SYan Zheng if (root->ref_cows && 5965d4f98a2SYan Zheng generation != btrfs_root_generation(&root->root_item)) 5975d4f98a2SYan Zheng return NULL; 5985d4f98a2SYan Zheng 5995d4f98a2SYan Zheng return root; 6005d4f98a2SYan Zheng } 6015d4f98a2SYan Zheng #endif 6025d4f98a2SYan Zheng 6035d4f98a2SYan Zheng static noinline_for_stack 6045d4f98a2SYan Zheng int find_inline_backref(struct extent_buffer *leaf, int slot, 6055d4f98a2SYan Zheng unsigned long *ptr, unsigned long *end) 6065d4f98a2SYan Zheng { 6075d4f98a2SYan Zheng struct btrfs_extent_item *ei; 6085d4f98a2SYan Zheng struct btrfs_tree_block_info *bi; 6095d4f98a2SYan Zheng u32 item_size; 6105d4f98a2SYan Zheng 6115d4f98a2SYan Zheng item_size = btrfs_item_size_nr(leaf, slot); 6125d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 6135d4f98a2SYan Zheng if (item_size < sizeof(*ei)) { 6145d4f98a2SYan Zheng WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0)); 6155d4f98a2SYan Zheng return 1; 6165d4f98a2SYan Zheng } 6175d4f98a2SYan Zheng #endif 6185d4f98a2SYan Zheng ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); 6195d4f98a2SYan Zheng WARN_ON(!(btrfs_extent_flags(leaf, ei) & 6205d4f98a2SYan Zheng BTRFS_EXTENT_FLAG_TREE_BLOCK)); 6215d4f98a2SYan Zheng 6225d4f98a2SYan Zheng if (item_size <= sizeof(*ei) + sizeof(*bi)) { 6235d4f98a2SYan Zheng WARN_ON(item_size < sizeof(*ei) + sizeof(*bi)); 6245d4f98a2SYan Zheng return 1; 6255d4f98a2SYan Zheng } 6265d4f98a2SYan Zheng 6275d4f98a2SYan Zheng bi = (struct btrfs_tree_block_info *)(ei + 1); 6285d4f98a2SYan Zheng *ptr = (unsigned long)(bi + 1); 6295d4f98a2SYan Zheng *end = (unsigned long)ei + item_size; 6305d4f98a2SYan Zheng return 0; 6315d4f98a2SYan Zheng } 6325d4f98a2SYan Zheng 6335d4f98a2SYan Zheng /* 6345d4f98a2SYan Zheng * build backref tree for a given tree block. root of the backref tree 6355d4f98a2SYan Zheng * corresponds the tree block, leaves of the backref tree correspond 6365d4f98a2SYan Zheng * roots of b-trees that reference the tree block. 6375d4f98a2SYan Zheng * 6385d4f98a2SYan Zheng * the basic idea of this function is check backrefs of a given block 6395d4f98a2SYan Zheng * to find upper level blocks that refernece the block, and then check 6405d4f98a2SYan Zheng * bakcrefs of these upper level blocks recursively. the recursion stop 6415d4f98a2SYan Zheng * when tree root is reached or backrefs for the block is cached. 6425d4f98a2SYan Zheng * 6435d4f98a2SYan Zheng * NOTE: if we find backrefs for a block are cached, we know backrefs 6445d4f98a2SYan Zheng * for all upper level blocks that directly/indirectly reference the 6455d4f98a2SYan Zheng * block are also cached. 6465d4f98a2SYan Zheng */ 6473fd0a558SYan, Zheng static noinline_for_stack 6483fd0a558SYan, Zheng struct backref_node *build_backref_tree(struct reloc_control *rc, 6495d4f98a2SYan Zheng struct btrfs_key *node_key, 6505d4f98a2SYan Zheng int level, u64 bytenr) 6515d4f98a2SYan Zheng { 6523fd0a558SYan, Zheng struct backref_cache *cache = &rc->backref_cache; 6535d4f98a2SYan Zheng struct btrfs_path *path1; 6545d4f98a2SYan Zheng struct btrfs_path *path2; 6555d4f98a2SYan Zheng struct extent_buffer *eb; 6565d4f98a2SYan Zheng struct btrfs_root *root; 6575d4f98a2SYan Zheng struct backref_node *cur; 6585d4f98a2SYan Zheng struct backref_node *upper; 6595d4f98a2SYan Zheng struct backref_node *lower; 6605d4f98a2SYan Zheng struct backref_node *node = NULL; 6615d4f98a2SYan Zheng struct backref_node *exist = NULL; 6625d4f98a2SYan Zheng struct backref_edge *edge; 6635d4f98a2SYan Zheng struct rb_node *rb_node; 6645d4f98a2SYan Zheng struct btrfs_key key; 6655d4f98a2SYan Zheng unsigned long end; 6665d4f98a2SYan Zheng unsigned long ptr; 6675d4f98a2SYan Zheng LIST_HEAD(list); 6683fd0a558SYan, Zheng LIST_HEAD(useless); 6693fd0a558SYan, Zheng int cowonly; 6705d4f98a2SYan Zheng int ret; 6715d4f98a2SYan Zheng int err = 0; 6725d4f98a2SYan Zheng 6735d4f98a2SYan Zheng path1 = btrfs_alloc_path(); 6745d4f98a2SYan Zheng path2 = btrfs_alloc_path(); 6755d4f98a2SYan Zheng if (!path1 || !path2) { 6765d4f98a2SYan Zheng err = -ENOMEM; 6775d4f98a2SYan Zheng goto out; 6785d4f98a2SYan Zheng } 6795d4f98a2SYan Zheng 6803fd0a558SYan, Zheng node = alloc_backref_node(cache); 6815d4f98a2SYan Zheng if (!node) { 6825d4f98a2SYan Zheng err = -ENOMEM; 6835d4f98a2SYan Zheng goto out; 6845d4f98a2SYan Zheng } 6855d4f98a2SYan Zheng 6865d4f98a2SYan Zheng node->bytenr = bytenr; 6875d4f98a2SYan Zheng node->level = level; 6885d4f98a2SYan Zheng node->lowest = 1; 6895d4f98a2SYan Zheng cur = node; 6905d4f98a2SYan Zheng again: 6915d4f98a2SYan Zheng end = 0; 6925d4f98a2SYan Zheng ptr = 0; 6935d4f98a2SYan Zheng key.objectid = cur->bytenr; 6945d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 6955d4f98a2SYan Zheng key.offset = (u64)-1; 6965d4f98a2SYan Zheng 6975d4f98a2SYan Zheng path1->search_commit_root = 1; 6985d4f98a2SYan Zheng path1->skip_locking = 1; 6995d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path1, 7005d4f98a2SYan Zheng 0, 0); 7015d4f98a2SYan Zheng if (ret < 0) { 7025d4f98a2SYan Zheng err = ret; 7035d4f98a2SYan Zheng goto out; 7045d4f98a2SYan Zheng } 7055d4f98a2SYan Zheng BUG_ON(!ret || !path1->slots[0]); 7065d4f98a2SYan Zheng 7075d4f98a2SYan Zheng path1->slots[0]--; 7085d4f98a2SYan Zheng 7095d4f98a2SYan Zheng WARN_ON(cur->checked); 7105d4f98a2SYan Zheng if (!list_empty(&cur->upper)) { 7115d4f98a2SYan Zheng /* 7125d4f98a2SYan Zheng * the backref was added previously when processsing 7135d4f98a2SYan Zheng * backref of type BTRFS_TREE_BLOCK_REF_KEY 7145d4f98a2SYan Zheng */ 7155d4f98a2SYan Zheng BUG_ON(!list_is_singular(&cur->upper)); 7165d4f98a2SYan Zheng edge = list_entry(cur->upper.next, struct backref_edge, 7175d4f98a2SYan Zheng list[LOWER]); 7185d4f98a2SYan Zheng BUG_ON(!list_empty(&edge->list[UPPER])); 7195d4f98a2SYan Zheng exist = edge->node[UPPER]; 7205d4f98a2SYan Zheng /* 7215d4f98a2SYan Zheng * add the upper level block to pending list if we need 7225d4f98a2SYan Zheng * check its backrefs 7235d4f98a2SYan Zheng */ 7245d4f98a2SYan Zheng if (!exist->checked) 7255d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 7265d4f98a2SYan Zheng } else { 7275d4f98a2SYan Zheng exist = NULL; 7285d4f98a2SYan Zheng } 7295d4f98a2SYan Zheng 7305d4f98a2SYan Zheng while (1) { 7315d4f98a2SYan Zheng cond_resched(); 7325d4f98a2SYan Zheng eb = path1->nodes[0]; 7335d4f98a2SYan Zheng 7345d4f98a2SYan Zheng if (ptr >= end) { 7355d4f98a2SYan Zheng if (path1->slots[0] >= btrfs_header_nritems(eb)) { 7365d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path1); 7375d4f98a2SYan Zheng if (ret < 0) { 7385d4f98a2SYan Zheng err = ret; 7395d4f98a2SYan Zheng goto out; 7405d4f98a2SYan Zheng } 7415d4f98a2SYan Zheng if (ret > 0) 7425d4f98a2SYan Zheng break; 7435d4f98a2SYan Zheng eb = path1->nodes[0]; 7445d4f98a2SYan Zheng } 7455d4f98a2SYan Zheng 7465d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &key, path1->slots[0]); 7475d4f98a2SYan Zheng if (key.objectid != cur->bytenr) { 7485d4f98a2SYan Zheng WARN_ON(exist); 7495d4f98a2SYan Zheng break; 7505d4f98a2SYan Zheng } 7515d4f98a2SYan Zheng 7525d4f98a2SYan Zheng if (key.type == BTRFS_EXTENT_ITEM_KEY) { 7535d4f98a2SYan Zheng ret = find_inline_backref(eb, path1->slots[0], 7545d4f98a2SYan Zheng &ptr, &end); 7555d4f98a2SYan Zheng if (ret) 7565d4f98a2SYan Zheng goto next; 7575d4f98a2SYan Zheng } 7585d4f98a2SYan Zheng } 7595d4f98a2SYan Zheng 7605d4f98a2SYan Zheng if (ptr < end) { 7615d4f98a2SYan Zheng /* update key for inline back ref */ 7625d4f98a2SYan Zheng struct btrfs_extent_inline_ref *iref; 7635d4f98a2SYan Zheng iref = (struct btrfs_extent_inline_ref *)ptr; 7645d4f98a2SYan Zheng key.type = btrfs_extent_inline_ref_type(eb, iref); 7655d4f98a2SYan Zheng key.offset = btrfs_extent_inline_ref_offset(eb, iref); 7665d4f98a2SYan Zheng WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY && 7675d4f98a2SYan Zheng key.type != BTRFS_SHARED_BLOCK_REF_KEY); 7685d4f98a2SYan Zheng } 7695d4f98a2SYan Zheng 7705d4f98a2SYan Zheng if (exist && 7715d4f98a2SYan Zheng ((key.type == BTRFS_TREE_BLOCK_REF_KEY && 7725d4f98a2SYan Zheng exist->owner == key.offset) || 7735d4f98a2SYan Zheng (key.type == BTRFS_SHARED_BLOCK_REF_KEY && 7745d4f98a2SYan Zheng exist->bytenr == key.offset))) { 7755d4f98a2SYan Zheng exist = NULL; 7765d4f98a2SYan Zheng goto next; 7775d4f98a2SYan Zheng } 7785d4f98a2SYan Zheng 7795d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 7805d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_BLOCK_REF_KEY || 7815d4f98a2SYan Zheng key.type == BTRFS_EXTENT_REF_V0_KEY) { 7823fd0a558SYan, Zheng if (key.type == BTRFS_EXTENT_REF_V0_KEY) { 7835d4f98a2SYan Zheng struct btrfs_extent_ref_v0 *ref0; 7845d4f98a2SYan Zheng ref0 = btrfs_item_ptr(eb, path1->slots[0], 7855d4f98a2SYan Zheng struct btrfs_extent_ref_v0); 7863fd0a558SYan, Zheng if (key.objectid == key.offset) { 787046f264fSYan, Zheng root = find_tree_root(rc, eb, ref0); 7883fd0a558SYan, Zheng if (root && !should_ignore_root(root)) 7895d4f98a2SYan Zheng cur->root = root; 7905d4f98a2SYan Zheng else 7913fd0a558SYan, Zheng list_add(&cur->list, &useless); 7925d4f98a2SYan Zheng break; 7935d4f98a2SYan Zheng } 794046f264fSYan, Zheng if (is_cowonly_root(btrfs_ref_root_v0(eb, 795046f264fSYan, Zheng ref0))) 796046f264fSYan, Zheng cur->cowonly = 1; 7973fd0a558SYan, Zheng } 7985d4f98a2SYan Zheng #else 7995d4f98a2SYan Zheng BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); 8005d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { 8015d4f98a2SYan Zheng #endif 8025d4f98a2SYan Zheng if (key.objectid == key.offset) { 8035d4f98a2SYan Zheng /* 8045d4f98a2SYan Zheng * only root blocks of reloc trees use 8055d4f98a2SYan Zheng * backref of this type. 8065d4f98a2SYan Zheng */ 8075d4f98a2SYan Zheng root = find_reloc_root(rc, cur->bytenr); 8085d4f98a2SYan Zheng BUG_ON(!root); 8095d4f98a2SYan Zheng cur->root = root; 8105d4f98a2SYan Zheng break; 8115d4f98a2SYan Zheng } 8125d4f98a2SYan Zheng 8133fd0a558SYan, Zheng edge = alloc_backref_edge(cache); 8145d4f98a2SYan Zheng if (!edge) { 8155d4f98a2SYan Zheng err = -ENOMEM; 8165d4f98a2SYan Zheng goto out; 8175d4f98a2SYan Zheng } 8185d4f98a2SYan Zheng rb_node = tree_search(&cache->rb_root, key.offset); 8195d4f98a2SYan Zheng if (!rb_node) { 8203fd0a558SYan, Zheng upper = alloc_backref_node(cache); 8215d4f98a2SYan Zheng if (!upper) { 8223fd0a558SYan, Zheng free_backref_edge(cache, edge); 8235d4f98a2SYan Zheng err = -ENOMEM; 8245d4f98a2SYan Zheng goto out; 8255d4f98a2SYan Zheng } 8265d4f98a2SYan Zheng upper->bytenr = key.offset; 8275d4f98a2SYan Zheng upper->level = cur->level + 1; 8285d4f98a2SYan Zheng /* 8295d4f98a2SYan Zheng * backrefs for the upper level block isn't 8305d4f98a2SYan Zheng * cached, add the block to pending list 8315d4f98a2SYan Zheng */ 8325d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 8335d4f98a2SYan Zheng } else { 8345d4f98a2SYan Zheng upper = rb_entry(rb_node, struct backref_node, 8355d4f98a2SYan Zheng rb_node); 8363fd0a558SYan, Zheng BUG_ON(!upper->checked); 8375d4f98a2SYan Zheng INIT_LIST_HEAD(&edge->list[UPPER]); 8385d4f98a2SYan Zheng } 8393fd0a558SYan, Zheng list_add_tail(&edge->list[LOWER], &cur->upper); 8405d4f98a2SYan Zheng edge->node[LOWER] = cur; 8413fd0a558SYan, Zheng edge->node[UPPER] = upper; 8425d4f98a2SYan Zheng 8435d4f98a2SYan Zheng goto next; 8445d4f98a2SYan Zheng } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { 8455d4f98a2SYan Zheng goto next; 8465d4f98a2SYan Zheng } 8475d4f98a2SYan Zheng 8485d4f98a2SYan Zheng /* key.type == BTRFS_TREE_BLOCK_REF_KEY */ 8495d4f98a2SYan Zheng root = read_fs_root(rc->extent_root->fs_info, key.offset); 8505d4f98a2SYan Zheng if (IS_ERR(root)) { 8515d4f98a2SYan Zheng err = PTR_ERR(root); 8525d4f98a2SYan Zheng goto out; 8535d4f98a2SYan Zheng } 8545d4f98a2SYan Zheng 8553fd0a558SYan, Zheng if (!root->ref_cows) 8563fd0a558SYan, Zheng cur->cowonly = 1; 8573fd0a558SYan, Zheng 8585d4f98a2SYan Zheng if (btrfs_root_level(&root->root_item) == cur->level) { 8595d4f98a2SYan Zheng /* tree root */ 8605d4f98a2SYan Zheng BUG_ON(btrfs_root_bytenr(&root->root_item) != 8615d4f98a2SYan Zheng cur->bytenr); 8623fd0a558SYan, Zheng if (should_ignore_root(root)) 8633fd0a558SYan, Zheng list_add(&cur->list, &useless); 8643fd0a558SYan, Zheng else 8655d4f98a2SYan Zheng cur->root = root; 8665d4f98a2SYan Zheng break; 8675d4f98a2SYan Zheng } 8685d4f98a2SYan Zheng 8695d4f98a2SYan Zheng level = cur->level + 1; 8705d4f98a2SYan Zheng 8715d4f98a2SYan Zheng /* 8725d4f98a2SYan Zheng * searching the tree to find upper level blocks 8735d4f98a2SYan Zheng * reference the block. 8745d4f98a2SYan Zheng */ 8755d4f98a2SYan Zheng path2->search_commit_root = 1; 8765d4f98a2SYan Zheng path2->skip_locking = 1; 8775d4f98a2SYan Zheng path2->lowest_level = level; 8785d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, root, node_key, path2, 0, 0); 8795d4f98a2SYan Zheng path2->lowest_level = 0; 8805d4f98a2SYan Zheng if (ret < 0) { 8815d4f98a2SYan Zheng err = ret; 8825d4f98a2SYan Zheng goto out; 8835d4f98a2SYan Zheng } 88433c66f43SYan Zheng if (ret > 0 && path2->slots[level] > 0) 88533c66f43SYan Zheng path2->slots[level]--; 8865d4f98a2SYan Zheng 8875d4f98a2SYan Zheng eb = path2->nodes[level]; 8885d4f98a2SYan Zheng WARN_ON(btrfs_node_blockptr(eb, path2->slots[level]) != 8895d4f98a2SYan Zheng cur->bytenr); 8905d4f98a2SYan Zheng 8915d4f98a2SYan Zheng lower = cur; 8925d4f98a2SYan Zheng for (; level < BTRFS_MAX_LEVEL; level++) { 8935d4f98a2SYan Zheng if (!path2->nodes[level]) { 8945d4f98a2SYan Zheng BUG_ON(btrfs_root_bytenr(&root->root_item) != 8955d4f98a2SYan Zheng lower->bytenr); 8963fd0a558SYan, Zheng if (should_ignore_root(root)) 8973fd0a558SYan, Zheng list_add(&lower->list, &useless); 8983fd0a558SYan, Zheng else 8995d4f98a2SYan Zheng lower->root = root; 9005d4f98a2SYan Zheng break; 9015d4f98a2SYan Zheng } 9025d4f98a2SYan Zheng 9033fd0a558SYan, Zheng edge = alloc_backref_edge(cache); 9045d4f98a2SYan Zheng if (!edge) { 9055d4f98a2SYan Zheng err = -ENOMEM; 9065d4f98a2SYan Zheng goto out; 9075d4f98a2SYan Zheng } 9085d4f98a2SYan Zheng 9095d4f98a2SYan Zheng eb = path2->nodes[level]; 9105d4f98a2SYan Zheng rb_node = tree_search(&cache->rb_root, eb->start); 9115d4f98a2SYan Zheng if (!rb_node) { 9123fd0a558SYan, Zheng upper = alloc_backref_node(cache); 9135d4f98a2SYan Zheng if (!upper) { 9143fd0a558SYan, Zheng free_backref_edge(cache, edge); 9155d4f98a2SYan Zheng err = -ENOMEM; 9165d4f98a2SYan Zheng goto out; 9175d4f98a2SYan Zheng } 9185d4f98a2SYan Zheng upper->bytenr = eb->start; 9195d4f98a2SYan Zheng upper->owner = btrfs_header_owner(eb); 9205d4f98a2SYan Zheng upper->level = lower->level + 1; 9213fd0a558SYan, Zheng if (!root->ref_cows) 9223fd0a558SYan, Zheng upper->cowonly = 1; 9235d4f98a2SYan Zheng 9245d4f98a2SYan Zheng /* 9255d4f98a2SYan Zheng * if we know the block isn't shared 9265d4f98a2SYan Zheng * we can void checking its backrefs. 9275d4f98a2SYan Zheng */ 9285d4f98a2SYan Zheng if (btrfs_block_can_be_shared(root, eb)) 9295d4f98a2SYan Zheng upper->checked = 0; 9305d4f98a2SYan Zheng else 9315d4f98a2SYan Zheng upper->checked = 1; 9325d4f98a2SYan Zheng 9335d4f98a2SYan Zheng /* 9345d4f98a2SYan Zheng * add the block to pending list if we 9355d4f98a2SYan Zheng * need check its backrefs. only block 9365d4f98a2SYan Zheng * at 'cur->level + 1' is added to the 9375d4f98a2SYan Zheng * tail of pending list. this guarantees 9385d4f98a2SYan Zheng * we check backrefs from lower level 9395d4f98a2SYan Zheng * blocks to upper level blocks. 9405d4f98a2SYan Zheng */ 9415d4f98a2SYan Zheng if (!upper->checked && 9425d4f98a2SYan Zheng level == cur->level + 1) { 9435d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], 9445d4f98a2SYan Zheng &list); 9455d4f98a2SYan Zheng } else 9465d4f98a2SYan Zheng INIT_LIST_HEAD(&edge->list[UPPER]); 9475d4f98a2SYan Zheng } else { 9485d4f98a2SYan Zheng upper = rb_entry(rb_node, struct backref_node, 9495d4f98a2SYan Zheng rb_node); 9505d4f98a2SYan Zheng BUG_ON(!upper->checked); 9515d4f98a2SYan Zheng INIT_LIST_HEAD(&edge->list[UPPER]); 9523fd0a558SYan, Zheng if (!upper->owner) 9533fd0a558SYan, Zheng upper->owner = btrfs_header_owner(eb); 9545d4f98a2SYan Zheng } 9555d4f98a2SYan Zheng list_add_tail(&edge->list[LOWER], &lower->upper); 9565d4f98a2SYan Zheng edge->node[LOWER] = lower; 9573fd0a558SYan, Zheng edge->node[UPPER] = upper; 9585d4f98a2SYan Zheng 9595d4f98a2SYan Zheng if (rb_node) 9605d4f98a2SYan Zheng break; 9615d4f98a2SYan Zheng lower = upper; 9625d4f98a2SYan Zheng upper = NULL; 9635d4f98a2SYan Zheng } 9645d4f98a2SYan Zheng btrfs_release_path(root, path2); 9655d4f98a2SYan Zheng next: 9665d4f98a2SYan Zheng if (ptr < end) { 9675d4f98a2SYan Zheng ptr += btrfs_extent_inline_ref_size(key.type); 9685d4f98a2SYan Zheng if (ptr >= end) { 9695d4f98a2SYan Zheng WARN_ON(ptr > end); 9705d4f98a2SYan Zheng ptr = 0; 9715d4f98a2SYan Zheng end = 0; 9725d4f98a2SYan Zheng } 9735d4f98a2SYan Zheng } 9745d4f98a2SYan Zheng if (ptr >= end) 9755d4f98a2SYan Zheng path1->slots[0]++; 9765d4f98a2SYan Zheng } 9775d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path1); 9785d4f98a2SYan Zheng 9795d4f98a2SYan Zheng cur->checked = 1; 9805d4f98a2SYan Zheng WARN_ON(exist); 9815d4f98a2SYan Zheng 9825d4f98a2SYan Zheng /* the pending list isn't empty, take the first block to process */ 9835d4f98a2SYan Zheng if (!list_empty(&list)) { 9845d4f98a2SYan Zheng edge = list_entry(list.next, struct backref_edge, list[UPPER]); 9855d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 9865d4f98a2SYan Zheng cur = edge->node[UPPER]; 9875d4f98a2SYan Zheng goto again; 9885d4f98a2SYan Zheng } 9895d4f98a2SYan Zheng 9905d4f98a2SYan Zheng /* 9915d4f98a2SYan Zheng * everything goes well, connect backref nodes and insert backref nodes 9925d4f98a2SYan Zheng * into the cache. 9935d4f98a2SYan Zheng */ 9945d4f98a2SYan Zheng BUG_ON(!node->checked); 9953fd0a558SYan, Zheng cowonly = node->cowonly; 9963fd0a558SYan, Zheng if (!cowonly) { 9973fd0a558SYan, Zheng rb_node = tree_insert(&cache->rb_root, node->bytenr, 9983fd0a558SYan, Zheng &node->rb_node); 9995d4f98a2SYan Zheng BUG_ON(rb_node); 10003fd0a558SYan, Zheng list_add_tail(&node->lower, &cache->leaves); 10013fd0a558SYan, Zheng } 10025d4f98a2SYan Zheng 10035d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) 10045d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 10055d4f98a2SYan Zheng 10065d4f98a2SYan Zheng while (!list_empty(&list)) { 10075d4f98a2SYan Zheng edge = list_entry(list.next, struct backref_edge, list[UPPER]); 10085d4f98a2SYan Zheng list_del_init(&edge->list[UPPER]); 10095d4f98a2SYan Zheng upper = edge->node[UPPER]; 10103fd0a558SYan, Zheng if (upper->detached) { 10113fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 10123fd0a558SYan, Zheng lower = edge->node[LOWER]; 10133fd0a558SYan, Zheng free_backref_edge(cache, edge); 10143fd0a558SYan, Zheng if (list_empty(&lower->upper)) 10153fd0a558SYan, Zheng list_add(&lower->list, &useless); 10163fd0a558SYan, Zheng continue; 10173fd0a558SYan, Zheng } 10185d4f98a2SYan Zheng 10195d4f98a2SYan Zheng if (!RB_EMPTY_NODE(&upper->rb_node)) { 10205d4f98a2SYan Zheng if (upper->lowest) { 10215d4f98a2SYan Zheng list_del_init(&upper->lower); 10225d4f98a2SYan Zheng upper->lowest = 0; 10235d4f98a2SYan Zheng } 10245d4f98a2SYan Zheng 10255d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &upper->lower); 10265d4f98a2SYan Zheng continue; 10275d4f98a2SYan Zheng } 10285d4f98a2SYan Zheng 10295d4f98a2SYan Zheng BUG_ON(!upper->checked); 10303fd0a558SYan, Zheng BUG_ON(cowonly != upper->cowonly); 10313fd0a558SYan, Zheng if (!cowonly) { 10325d4f98a2SYan Zheng rb_node = tree_insert(&cache->rb_root, upper->bytenr, 10335d4f98a2SYan Zheng &upper->rb_node); 10345d4f98a2SYan Zheng BUG_ON(rb_node); 10353fd0a558SYan, Zheng } 10365d4f98a2SYan Zheng 10375d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &upper->lower); 10385d4f98a2SYan Zheng 10395d4f98a2SYan Zheng list_for_each_entry(edge, &upper->upper, list[LOWER]) 10405d4f98a2SYan Zheng list_add_tail(&edge->list[UPPER], &list); 10415d4f98a2SYan Zheng } 10423fd0a558SYan, Zheng /* 10433fd0a558SYan, Zheng * process useless backref nodes. backref nodes for tree leaves 10443fd0a558SYan, Zheng * are deleted from the cache. backref nodes for upper level 10453fd0a558SYan, Zheng * tree blocks are left in the cache to avoid unnecessary backref 10463fd0a558SYan, Zheng * lookup. 10473fd0a558SYan, Zheng */ 10483fd0a558SYan, Zheng while (!list_empty(&useless)) { 10493fd0a558SYan, Zheng upper = list_entry(useless.next, struct backref_node, list); 10503fd0a558SYan, Zheng list_del_init(&upper->list); 10513fd0a558SYan, Zheng BUG_ON(!list_empty(&upper->upper)); 10523fd0a558SYan, Zheng if (upper == node) 10533fd0a558SYan, Zheng node = NULL; 10543fd0a558SYan, Zheng if (upper->lowest) { 10553fd0a558SYan, Zheng list_del_init(&upper->lower); 10563fd0a558SYan, Zheng upper->lowest = 0; 10573fd0a558SYan, Zheng } 10583fd0a558SYan, Zheng while (!list_empty(&upper->lower)) { 10593fd0a558SYan, Zheng edge = list_entry(upper->lower.next, 10603fd0a558SYan, Zheng struct backref_edge, list[UPPER]); 10613fd0a558SYan, Zheng list_del(&edge->list[UPPER]); 10623fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 10633fd0a558SYan, Zheng lower = edge->node[LOWER]; 10643fd0a558SYan, Zheng free_backref_edge(cache, edge); 10653fd0a558SYan, Zheng 10663fd0a558SYan, Zheng if (list_empty(&lower->upper)) 10673fd0a558SYan, Zheng list_add(&lower->list, &useless); 10683fd0a558SYan, Zheng } 10693fd0a558SYan, Zheng __mark_block_processed(rc, upper); 10703fd0a558SYan, Zheng if (upper->level > 0) { 10713fd0a558SYan, Zheng list_add(&upper->list, &cache->detached); 10723fd0a558SYan, Zheng upper->detached = 1; 10733fd0a558SYan, Zheng } else { 10743fd0a558SYan, Zheng rb_erase(&upper->rb_node, &cache->rb_root); 10753fd0a558SYan, Zheng free_backref_node(cache, upper); 10763fd0a558SYan, Zheng } 10773fd0a558SYan, Zheng } 10785d4f98a2SYan Zheng out: 10795d4f98a2SYan Zheng btrfs_free_path(path1); 10805d4f98a2SYan Zheng btrfs_free_path(path2); 10815d4f98a2SYan Zheng if (err) { 10823fd0a558SYan, Zheng while (!list_empty(&useless)) { 10833fd0a558SYan, Zheng lower = list_entry(useless.next, 10843fd0a558SYan, Zheng struct backref_node, upper); 10853fd0a558SYan, Zheng list_del_init(&lower->upper); 10863fd0a558SYan, Zheng } 10875d4f98a2SYan Zheng upper = node; 10883fd0a558SYan, Zheng INIT_LIST_HEAD(&list); 10895d4f98a2SYan Zheng while (upper) { 10905d4f98a2SYan Zheng if (RB_EMPTY_NODE(&upper->rb_node)) { 10915d4f98a2SYan Zheng list_splice_tail(&upper->upper, &list); 10923fd0a558SYan, Zheng free_backref_node(cache, upper); 10935d4f98a2SYan Zheng } 10945d4f98a2SYan Zheng 10955d4f98a2SYan Zheng if (list_empty(&list)) 10965d4f98a2SYan Zheng break; 10975d4f98a2SYan Zheng 10985d4f98a2SYan Zheng edge = list_entry(list.next, struct backref_edge, 10995d4f98a2SYan Zheng list[LOWER]); 11003fd0a558SYan, Zheng list_del(&edge->list[LOWER]); 11015d4f98a2SYan Zheng upper = edge->node[UPPER]; 11023fd0a558SYan, Zheng free_backref_edge(cache, edge); 11035d4f98a2SYan Zheng } 11045d4f98a2SYan Zheng return ERR_PTR(err); 11055d4f98a2SYan Zheng } 11063fd0a558SYan, Zheng BUG_ON(node && node->detached); 11075d4f98a2SYan Zheng return node; 11085d4f98a2SYan Zheng } 11095d4f98a2SYan Zheng 11105d4f98a2SYan Zheng /* 11113fd0a558SYan, Zheng * helper to add backref node for the newly created snapshot. 11123fd0a558SYan, Zheng * the backref node is created by cloning backref node that 11133fd0a558SYan, Zheng * corresponds to root of source tree 11143fd0a558SYan, Zheng */ 11153fd0a558SYan, Zheng static int clone_backref_node(struct btrfs_trans_handle *trans, 11163fd0a558SYan, Zheng struct reloc_control *rc, 11173fd0a558SYan, Zheng struct btrfs_root *src, 11183fd0a558SYan, Zheng struct btrfs_root *dest) 11193fd0a558SYan, Zheng { 11203fd0a558SYan, Zheng struct btrfs_root *reloc_root = src->reloc_root; 11213fd0a558SYan, Zheng struct backref_cache *cache = &rc->backref_cache; 11223fd0a558SYan, Zheng struct backref_node *node = NULL; 11233fd0a558SYan, Zheng struct backref_node *new_node; 11243fd0a558SYan, Zheng struct backref_edge *edge; 11253fd0a558SYan, Zheng struct backref_edge *new_edge; 11263fd0a558SYan, Zheng struct rb_node *rb_node; 11273fd0a558SYan, Zheng 11283fd0a558SYan, Zheng if (cache->last_trans > 0) 11293fd0a558SYan, Zheng update_backref_cache(trans, cache); 11303fd0a558SYan, Zheng 11313fd0a558SYan, Zheng rb_node = tree_search(&cache->rb_root, src->commit_root->start); 11323fd0a558SYan, Zheng if (rb_node) { 11333fd0a558SYan, Zheng node = rb_entry(rb_node, struct backref_node, rb_node); 11343fd0a558SYan, Zheng if (node->detached) 11353fd0a558SYan, Zheng node = NULL; 11363fd0a558SYan, Zheng else 11373fd0a558SYan, Zheng BUG_ON(node->new_bytenr != reloc_root->node->start); 11383fd0a558SYan, Zheng } 11393fd0a558SYan, Zheng 11403fd0a558SYan, Zheng if (!node) { 11413fd0a558SYan, Zheng rb_node = tree_search(&cache->rb_root, 11423fd0a558SYan, Zheng reloc_root->commit_root->start); 11433fd0a558SYan, Zheng if (rb_node) { 11443fd0a558SYan, Zheng node = rb_entry(rb_node, struct backref_node, 11453fd0a558SYan, Zheng rb_node); 11463fd0a558SYan, Zheng BUG_ON(node->detached); 11473fd0a558SYan, Zheng } 11483fd0a558SYan, Zheng } 11493fd0a558SYan, Zheng 11503fd0a558SYan, Zheng if (!node) 11513fd0a558SYan, Zheng return 0; 11523fd0a558SYan, Zheng 11533fd0a558SYan, Zheng new_node = alloc_backref_node(cache); 11543fd0a558SYan, Zheng if (!new_node) 11553fd0a558SYan, Zheng return -ENOMEM; 11563fd0a558SYan, Zheng 11573fd0a558SYan, Zheng new_node->bytenr = dest->node->start; 11583fd0a558SYan, Zheng new_node->level = node->level; 11593fd0a558SYan, Zheng new_node->lowest = node->lowest; 11603fd0a558SYan, Zheng new_node->root = dest; 11613fd0a558SYan, Zheng 11623fd0a558SYan, Zheng if (!node->lowest) { 11633fd0a558SYan, Zheng list_for_each_entry(edge, &node->lower, list[UPPER]) { 11643fd0a558SYan, Zheng new_edge = alloc_backref_edge(cache); 11653fd0a558SYan, Zheng if (!new_edge) 11663fd0a558SYan, Zheng goto fail; 11673fd0a558SYan, Zheng 11683fd0a558SYan, Zheng new_edge->node[UPPER] = new_node; 11693fd0a558SYan, Zheng new_edge->node[LOWER] = edge->node[LOWER]; 11703fd0a558SYan, Zheng list_add_tail(&new_edge->list[UPPER], 11713fd0a558SYan, Zheng &new_node->lower); 11723fd0a558SYan, Zheng } 11733fd0a558SYan, Zheng } 11743fd0a558SYan, Zheng 11753fd0a558SYan, Zheng rb_node = tree_insert(&cache->rb_root, new_node->bytenr, 11763fd0a558SYan, Zheng &new_node->rb_node); 11773fd0a558SYan, Zheng BUG_ON(rb_node); 11783fd0a558SYan, Zheng 11793fd0a558SYan, Zheng if (!new_node->lowest) { 11803fd0a558SYan, Zheng list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) { 11813fd0a558SYan, Zheng list_add_tail(&new_edge->list[LOWER], 11823fd0a558SYan, Zheng &new_edge->node[LOWER]->upper); 11833fd0a558SYan, Zheng } 11843fd0a558SYan, Zheng } 11853fd0a558SYan, Zheng return 0; 11863fd0a558SYan, Zheng fail: 11873fd0a558SYan, Zheng while (!list_empty(&new_node->lower)) { 11883fd0a558SYan, Zheng new_edge = list_entry(new_node->lower.next, 11893fd0a558SYan, Zheng struct backref_edge, list[UPPER]); 11903fd0a558SYan, Zheng list_del(&new_edge->list[UPPER]); 11913fd0a558SYan, Zheng free_backref_edge(cache, new_edge); 11923fd0a558SYan, Zheng } 11933fd0a558SYan, Zheng free_backref_node(cache, new_node); 11943fd0a558SYan, Zheng return -ENOMEM; 11953fd0a558SYan, Zheng } 11963fd0a558SYan, Zheng 11973fd0a558SYan, Zheng /* 11985d4f98a2SYan Zheng * helper to add 'address of tree root -> reloc tree' mapping 11995d4f98a2SYan Zheng */ 12005d4f98a2SYan Zheng static int __add_reloc_root(struct btrfs_root *root) 12015d4f98a2SYan Zheng { 12025d4f98a2SYan Zheng struct rb_node *rb_node; 12035d4f98a2SYan Zheng struct mapping_node *node; 12045d4f98a2SYan Zheng struct reloc_control *rc = root->fs_info->reloc_ctl; 12055d4f98a2SYan Zheng 12065d4f98a2SYan Zheng node = kmalloc(sizeof(*node), GFP_NOFS); 12075d4f98a2SYan Zheng BUG_ON(!node); 12085d4f98a2SYan Zheng 12095d4f98a2SYan Zheng node->bytenr = root->node->start; 12105d4f98a2SYan Zheng node->data = root; 12115d4f98a2SYan Zheng 12125d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 12135d4f98a2SYan Zheng rb_node = tree_insert(&rc->reloc_root_tree.rb_root, 12145d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12155d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 12165d4f98a2SYan Zheng BUG_ON(rb_node); 12175d4f98a2SYan Zheng 12185d4f98a2SYan Zheng list_add_tail(&root->root_list, &rc->reloc_roots); 12195d4f98a2SYan Zheng return 0; 12205d4f98a2SYan Zheng } 12215d4f98a2SYan Zheng 12225d4f98a2SYan Zheng /* 12235d4f98a2SYan Zheng * helper to update/delete the 'address of tree root -> reloc tree' 12245d4f98a2SYan Zheng * mapping 12255d4f98a2SYan Zheng */ 12265d4f98a2SYan Zheng static int __update_reloc_root(struct btrfs_root *root, int del) 12275d4f98a2SYan Zheng { 12285d4f98a2SYan Zheng struct rb_node *rb_node; 12295d4f98a2SYan Zheng struct mapping_node *node = NULL; 12305d4f98a2SYan Zheng struct reloc_control *rc = root->fs_info->reloc_ctl; 12315d4f98a2SYan Zheng 12325d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 12335d4f98a2SYan Zheng rb_node = tree_search(&rc->reloc_root_tree.rb_root, 12345d4f98a2SYan Zheng root->commit_root->start); 12355d4f98a2SYan Zheng if (rb_node) { 12365d4f98a2SYan Zheng node = rb_entry(rb_node, struct mapping_node, rb_node); 12375d4f98a2SYan Zheng rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); 12385d4f98a2SYan Zheng } 12395d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 12405d4f98a2SYan Zheng 12415d4f98a2SYan Zheng BUG_ON((struct btrfs_root *)node->data != root); 12425d4f98a2SYan Zheng 12435d4f98a2SYan Zheng if (!del) { 12445d4f98a2SYan Zheng spin_lock(&rc->reloc_root_tree.lock); 12455d4f98a2SYan Zheng node->bytenr = root->node->start; 12465d4f98a2SYan Zheng rb_node = tree_insert(&rc->reloc_root_tree.rb_root, 12475d4f98a2SYan Zheng node->bytenr, &node->rb_node); 12485d4f98a2SYan Zheng spin_unlock(&rc->reloc_root_tree.lock); 12495d4f98a2SYan Zheng BUG_ON(rb_node); 12505d4f98a2SYan Zheng } else { 12515d4f98a2SYan Zheng list_del_init(&root->root_list); 12525d4f98a2SYan Zheng kfree(node); 12535d4f98a2SYan Zheng } 12545d4f98a2SYan Zheng return 0; 12555d4f98a2SYan Zheng } 12565d4f98a2SYan Zheng 12573fd0a558SYan, Zheng static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, 12583fd0a558SYan, Zheng struct btrfs_root *root, u64 objectid) 12595d4f98a2SYan Zheng { 12605d4f98a2SYan Zheng struct btrfs_root *reloc_root; 12615d4f98a2SYan Zheng struct extent_buffer *eb; 12625d4f98a2SYan Zheng struct btrfs_root_item *root_item; 12635d4f98a2SYan Zheng struct btrfs_key root_key; 12645d4f98a2SYan Zheng int ret; 12655d4f98a2SYan Zheng 12665d4f98a2SYan Zheng root_item = kmalloc(sizeof(*root_item), GFP_NOFS); 12675d4f98a2SYan Zheng BUG_ON(!root_item); 12685d4f98a2SYan Zheng 12695d4f98a2SYan Zheng root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; 12705d4f98a2SYan Zheng root_key.type = BTRFS_ROOT_ITEM_KEY; 12713fd0a558SYan, Zheng root_key.offset = objectid; 12725d4f98a2SYan Zheng 12733fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 12743fd0a558SYan, Zheng /* called by btrfs_init_reloc_root */ 12755d4f98a2SYan Zheng ret = btrfs_copy_root(trans, root, root->commit_root, &eb, 12765d4f98a2SYan Zheng BTRFS_TREE_RELOC_OBJECTID); 12775d4f98a2SYan Zheng BUG_ON(ret); 12785d4f98a2SYan Zheng 12793fd0a558SYan, Zheng btrfs_set_root_last_snapshot(&root->root_item, 12803fd0a558SYan, Zheng trans->transid - 1); 12813fd0a558SYan, Zheng } else { 12823fd0a558SYan, Zheng /* 12833fd0a558SYan, Zheng * called by btrfs_reloc_post_snapshot_hook. 12843fd0a558SYan, Zheng * the source tree is a reloc tree, all tree blocks 12853fd0a558SYan, Zheng * modified after it was created have RELOC flag 12863fd0a558SYan, Zheng * set in their headers. so it's OK to not update 12873fd0a558SYan, Zheng * the 'last_snapshot'. 12883fd0a558SYan, Zheng */ 12893fd0a558SYan, Zheng ret = btrfs_copy_root(trans, root, root->node, &eb, 12903fd0a558SYan, Zheng BTRFS_TREE_RELOC_OBJECTID); 12913fd0a558SYan, Zheng BUG_ON(ret); 12923fd0a558SYan, Zheng } 12933fd0a558SYan, Zheng 12945d4f98a2SYan Zheng memcpy(root_item, &root->root_item, sizeof(*root_item)); 12955d4f98a2SYan Zheng btrfs_set_root_bytenr(root_item, eb->start); 12965d4f98a2SYan Zheng btrfs_set_root_level(root_item, btrfs_header_level(eb)); 12975d4f98a2SYan Zheng btrfs_set_root_generation(root_item, trans->transid); 12983fd0a558SYan, Zheng 12993fd0a558SYan, Zheng if (root->root_key.objectid == objectid) { 13003fd0a558SYan, Zheng btrfs_set_root_refs(root_item, 0); 13013fd0a558SYan, Zheng memset(&root_item->drop_progress, 0, 13023fd0a558SYan, Zheng sizeof(struct btrfs_disk_key)); 13035d4f98a2SYan Zheng root_item->drop_level = 0; 13043fd0a558SYan, Zheng } 13055d4f98a2SYan Zheng 13065d4f98a2SYan Zheng btrfs_tree_unlock(eb); 13075d4f98a2SYan Zheng free_extent_buffer(eb); 13085d4f98a2SYan Zheng 13095d4f98a2SYan Zheng ret = btrfs_insert_root(trans, root->fs_info->tree_root, 13105d4f98a2SYan Zheng &root_key, root_item); 13115d4f98a2SYan Zheng BUG_ON(ret); 13125d4f98a2SYan Zheng kfree(root_item); 13135d4f98a2SYan Zheng 13145d4f98a2SYan Zheng reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root, 13155d4f98a2SYan Zheng &root_key); 13165d4f98a2SYan Zheng BUG_ON(IS_ERR(reloc_root)); 13175d4f98a2SYan Zheng reloc_root->last_trans = trans->transid; 13183fd0a558SYan, Zheng return reloc_root; 13193fd0a558SYan, Zheng } 13203fd0a558SYan, Zheng 13213fd0a558SYan, Zheng /* 13223fd0a558SYan, Zheng * create reloc tree for a given fs tree. reloc tree is just a 13233fd0a558SYan, Zheng * snapshot of the fs tree with special root objectid. 13243fd0a558SYan, Zheng */ 13253fd0a558SYan, Zheng int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, 13263fd0a558SYan, Zheng struct btrfs_root *root) 13273fd0a558SYan, Zheng { 13283fd0a558SYan, Zheng struct btrfs_root *reloc_root; 13293fd0a558SYan, Zheng struct reloc_control *rc = root->fs_info->reloc_ctl; 13303fd0a558SYan, Zheng int clear_rsv = 0; 13313fd0a558SYan, Zheng 13323fd0a558SYan, Zheng if (root->reloc_root) { 13333fd0a558SYan, Zheng reloc_root = root->reloc_root; 13343fd0a558SYan, Zheng reloc_root->last_trans = trans->transid; 13353fd0a558SYan, Zheng return 0; 13363fd0a558SYan, Zheng } 13373fd0a558SYan, Zheng 13383fd0a558SYan, Zheng if (!rc || !rc->create_reloc_tree || 13393fd0a558SYan, Zheng root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 13403fd0a558SYan, Zheng return 0; 13413fd0a558SYan, Zheng 13423fd0a558SYan, Zheng if (!trans->block_rsv) { 13433fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 13443fd0a558SYan, Zheng clear_rsv = 1; 13453fd0a558SYan, Zheng } 13463fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root, root->root_key.objectid); 13473fd0a558SYan, Zheng if (clear_rsv) 13483fd0a558SYan, Zheng trans->block_rsv = NULL; 13495d4f98a2SYan Zheng 13505d4f98a2SYan Zheng __add_reloc_root(reloc_root); 13515d4f98a2SYan Zheng root->reloc_root = reloc_root; 13525d4f98a2SYan Zheng return 0; 13535d4f98a2SYan Zheng } 13545d4f98a2SYan Zheng 13555d4f98a2SYan Zheng /* 13565d4f98a2SYan Zheng * update root item of reloc tree 13575d4f98a2SYan Zheng */ 13585d4f98a2SYan Zheng int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, 13595d4f98a2SYan Zheng struct btrfs_root *root) 13605d4f98a2SYan Zheng { 13615d4f98a2SYan Zheng struct btrfs_root *reloc_root; 13625d4f98a2SYan Zheng struct btrfs_root_item *root_item; 13635d4f98a2SYan Zheng int del = 0; 13645d4f98a2SYan Zheng int ret; 13655d4f98a2SYan Zheng 13665d4f98a2SYan Zheng if (!root->reloc_root) 13675d4f98a2SYan Zheng return 0; 13685d4f98a2SYan Zheng 13695d4f98a2SYan Zheng reloc_root = root->reloc_root; 13705d4f98a2SYan Zheng root_item = &reloc_root->root_item; 13715d4f98a2SYan Zheng 13723fd0a558SYan, Zheng if (root->fs_info->reloc_ctl->merge_reloc_tree && 13733fd0a558SYan, Zheng btrfs_root_refs(root_item) == 0) { 13745d4f98a2SYan Zheng root->reloc_root = NULL; 13755d4f98a2SYan Zheng del = 1; 13765d4f98a2SYan Zheng } 13775d4f98a2SYan Zheng 13785d4f98a2SYan Zheng __update_reloc_root(reloc_root, del); 13795d4f98a2SYan Zheng 13805d4f98a2SYan Zheng if (reloc_root->commit_root != reloc_root->node) { 13815d4f98a2SYan Zheng btrfs_set_root_node(root_item, reloc_root->node); 13825d4f98a2SYan Zheng free_extent_buffer(reloc_root->commit_root); 13835d4f98a2SYan Zheng reloc_root->commit_root = btrfs_root_node(reloc_root); 13845d4f98a2SYan Zheng } 13855d4f98a2SYan Zheng 13865d4f98a2SYan Zheng ret = btrfs_update_root(trans, root->fs_info->tree_root, 13875d4f98a2SYan Zheng &reloc_root->root_key, root_item); 13885d4f98a2SYan Zheng BUG_ON(ret); 13895d4f98a2SYan Zheng return 0; 13905d4f98a2SYan Zheng } 13915d4f98a2SYan Zheng 13925d4f98a2SYan Zheng /* 13935d4f98a2SYan Zheng * helper to find first cached inode with inode number >= objectid 13945d4f98a2SYan Zheng * in a subvolume 13955d4f98a2SYan Zheng */ 13965d4f98a2SYan Zheng static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) 13975d4f98a2SYan Zheng { 13985d4f98a2SYan Zheng struct rb_node *node; 13995d4f98a2SYan Zheng struct rb_node *prev; 14005d4f98a2SYan Zheng struct btrfs_inode *entry; 14015d4f98a2SYan Zheng struct inode *inode; 14025d4f98a2SYan Zheng 14035d4f98a2SYan Zheng spin_lock(&root->inode_lock); 14045d4f98a2SYan Zheng again: 14055d4f98a2SYan Zheng node = root->inode_tree.rb_node; 14065d4f98a2SYan Zheng prev = NULL; 14075d4f98a2SYan Zheng while (node) { 14085d4f98a2SYan Zheng prev = node; 14095d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 14105d4f98a2SYan Zheng 14115d4f98a2SYan Zheng if (objectid < entry->vfs_inode.i_ino) 14125d4f98a2SYan Zheng node = node->rb_left; 14135d4f98a2SYan Zheng else if (objectid > entry->vfs_inode.i_ino) 14145d4f98a2SYan Zheng node = node->rb_right; 14155d4f98a2SYan Zheng else 14165d4f98a2SYan Zheng break; 14175d4f98a2SYan Zheng } 14185d4f98a2SYan Zheng if (!node) { 14195d4f98a2SYan Zheng while (prev) { 14205d4f98a2SYan Zheng entry = rb_entry(prev, struct btrfs_inode, rb_node); 14215d4f98a2SYan Zheng if (objectid <= entry->vfs_inode.i_ino) { 14225d4f98a2SYan Zheng node = prev; 14235d4f98a2SYan Zheng break; 14245d4f98a2SYan Zheng } 14255d4f98a2SYan Zheng prev = rb_next(prev); 14265d4f98a2SYan Zheng } 14275d4f98a2SYan Zheng } 14285d4f98a2SYan Zheng while (node) { 14295d4f98a2SYan Zheng entry = rb_entry(node, struct btrfs_inode, rb_node); 14305d4f98a2SYan Zheng inode = igrab(&entry->vfs_inode); 14315d4f98a2SYan Zheng if (inode) { 14325d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 14335d4f98a2SYan Zheng return inode; 14345d4f98a2SYan Zheng } 14355d4f98a2SYan Zheng 14365d4f98a2SYan Zheng objectid = entry->vfs_inode.i_ino + 1; 14375d4f98a2SYan Zheng if (cond_resched_lock(&root->inode_lock)) 14385d4f98a2SYan Zheng goto again; 14395d4f98a2SYan Zheng 14405d4f98a2SYan Zheng node = rb_next(node); 14415d4f98a2SYan Zheng } 14425d4f98a2SYan Zheng spin_unlock(&root->inode_lock); 14435d4f98a2SYan Zheng return NULL; 14445d4f98a2SYan Zheng } 14455d4f98a2SYan Zheng 14465d4f98a2SYan Zheng static int in_block_group(u64 bytenr, 14475d4f98a2SYan Zheng struct btrfs_block_group_cache *block_group) 14485d4f98a2SYan Zheng { 14495d4f98a2SYan Zheng if (bytenr >= block_group->key.objectid && 14505d4f98a2SYan Zheng bytenr < block_group->key.objectid + block_group->key.offset) 14515d4f98a2SYan Zheng return 1; 14525d4f98a2SYan Zheng return 0; 14535d4f98a2SYan Zheng } 14545d4f98a2SYan Zheng 14555d4f98a2SYan Zheng /* 14565d4f98a2SYan Zheng * get new location of data 14575d4f98a2SYan Zheng */ 14585d4f98a2SYan Zheng static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, 14595d4f98a2SYan Zheng u64 bytenr, u64 num_bytes) 14605d4f98a2SYan Zheng { 14615d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(reloc_inode)->root; 14625d4f98a2SYan Zheng struct btrfs_path *path; 14635d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 14645d4f98a2SYan Zheng struct extent_buffer *leaf; 14655d4f98a2SYan Zheng int ret; 14665d4f98a2SYan Zheng 14675d4f98a2SYan Zheng path = btrfs_alloc_path(); 14685d4f98a2SYan Zheng if (!path) 14695d4f98a2SYan Zheng return -ENOMEM; 14705d4f98a2SYan Zheng 14715d4f98a2SYan Zheng bytenr -= BTRFS_I(reloc_inode)->index_cnt; 14725d4f98a2SYan Zheng ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino, 14735d4f98a2SYan Zheng bytenr, 0); 14745d4f98a2SYan Zheng if (ret < 0) 14755d4f98a2SYan Zheng goto out; 14765d4f98a2SYan Zheng if (ret > 0) { 14775d4f98a2SYan Zheng ret = -ENOENT; 14785d4f98a2SYan Zheng goto out; 14795d4f98a2SYan Zheng } 14805d4f98a2SYan Zheng 14815d4f98a2SYan Zheng leaf = path->nodes[0]; 14825d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, path->slots[0], 14835d4f98a2SYan Zheng struct btrfs_file_extent_item); 14845d4f98a2SYan Zheng 14855d4f98a2SYan Zheng BUG_ON(btrfs_file_extent_offset(leaf, fi) || 14865d4f98a2SYan Zheng btrfs_file_extent_compression(leaf, fi) || 14875d4f98a2SYan Zheng btrfs_file_extent_encryption(leaf, fi) || 14885d4f98a2SYan Zheng btrfs_file_extent_other_encoding(leaf, fi)); 14895d4f98a2SYan Zheng 14905d4f98a2SYan Zheng if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { 14915d4f98a2SYan Zheng ret = 1; 14925d4f98a2SYan Zheng goto out; 14935d4f98a2SYan Zheng } 14945d4f98a2SYan Zheng 14955d4f98a2SYan Zheng *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 14965d4f98a2SYan Zheng ret = 0; 14975d4f98a2SYan Zheng out: 14985d4f98a2SYan Zheng btrfs_free_path(path); 14995d4f98a2SYan Zheng return ret; 15005d4f98a2SYan Zheng } 15015d4f98a2SYan Zheng 15025d4f98a2SYan Zheng /* 15035d4f98a2SYan Zheng * update file extent items in the tree leaf to point to 15045d4f98a2SYan Zheng * the new locations. 15055d4f98a2SYan Zheng */ 15063fd0a558SYan, Zheng static noinline_for_stack 15073fd0a558SYan, Zheng int replace_file_extents(struct btrfs_trans_handle *trans, 15085d4f98a2SYan Zheng struct reloc_control *rc, 15095d4f98a2SYan Zheng struct btrfs_root *root, 15103fd0a558SYan, Zheng struct extent_buffer *leaf) 15115d4f98a2SYan Zheng { 15125d4f98a2SYan Zheng struct btrfs_key key; 15135d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 15145d4f98a2SYan Zheng struct inode *inode = NULL; 15155d4f98a2SYan Zheng u64 parent; 15165d4f98a2SYan Zheng u64 bytenr; 15173fd0a558SYan, Zheng u64 new_bytenr = 0; 15185d4f98a2SYan Zheng u64 num_bytes; 15195d4f98a2SYan Zheng u64 end; 15205d4f98a2SYan Zheng u32 nritems; 15215d4f98a2SYan Zheng u32 i; 15225d4f98a2SYan Zheng int ret; 15235d4f98a2SYan Zheng int first = 1; 15245d4f98a2SYan Zheng int dirty = 0; 15255d4f98a2SYan Zheng 15265d4f98a2SYan Zheng if (rc->stage != UPDATE_DATA_PTRS) 15275d4f98a2SYan Zheng return 0; 15285d4f98a2SYan Zheng 15295d4f98a2SYan Zheng /* reloc trees always use full backref */ 15305d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) 15315d4f98a2SYan Zheng parent = leaf->start; 15325d4f98a2SYan Zheng else 15335d4f98a2SYan Zheng parent = 0; 15345d4f98a2SYan Zheng 15355d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 15365d4f98a2SYan Zheng for (i = 0; i < nritems; i++) { 15375d4f98a2SYan Zheng cond_resched(); 15385d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, i); 15395d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_DATA_KEY) 15405d4f98a2SYan Zheng continue; 15415d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); 15425d4f98a2SYan Zheng if (btrfs_file_extent_type(leaf, fi) == 15435d4f98a2SYan Zheng BTRFS_FILE_EXTENT_INLINE) 15445d4f98a2SYan Zheng continue; 15455d4f98a2SYan Zheng bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); 15465d4f98a2SYan Zheng num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); 15475d4f98a2SYan Zheng if (bytenr == 0) 15485d4f98a2SYan Zheng continue; 15495d4f98a2SYan Zheng if (!in_block_group(bytenr, rc->block_group)) 15505d4f98a2SYan Zheng continue; 15515d4f98a2SYan Zheng 15525d4f98a2SYan Zheng /* 15535d4f98a2SYan Zheng * if we are modifying block in fs tree, wait for readpage 15545d4f98a2SYan Zheng * to complete and drop the extent cache 15555d4f98a2SYan Zheng */ 15565d4f98a2SYan Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { 15575d4f98a2SYan Zheng if (first) { 15585d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 15595d4f98a2SYan Zheng first = 0; 15605d4f98a2SYan Zheng } else if (inode && inode->i_ino < key.objectid) { 15613fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 15625d4f98a2SYan Zheng inode = find_next_inode(root, key.objectid); 15635d4f98a2SYan Zheng } 15645d4f98a2SYan Zheng if (inode && inode->i_ino == key.objectid) { 15655d4f98a2SYan Zheng end = key.offset + 15665d4f98a2SYan Zheng btrfs_file_extent_num_bytes(leaf, fi); 15675d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(key.offset, 15685d4f98a2SYan Zheng root->sectorsize)); 15695d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(end, root->sectorsize)); 15705d4f98a2SYan Zheng end--; 15715d4f98a2SYan Zheng ret = try_lock_extent(&BTRFS_I(inode)->io_tree, 15725d4f98a2SYan Zheng key.offset, end, 15735d4f98a2SYan Zheng GFP_NOFS); 15745d4f98a2SYan Zheng if (!ret) 15755d4f98a2SYan Zheng continue; 15765d4f98a2SYan Zheng 15775d4f98a2SYan Zheng btrfs_drop_extent_cache(inode, key.offset, end, 15785d4f98a2SYan Zheng 1); 15795d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 15805d4f98a2SYan Zheng key.offset, end, GFP_NOFS); 15815d4f98a2SYan Zheng } 15825d4f98a2SYan Zheng } 15835d4f98a2SYan Zheng 15845d4f98a2SYan Zheng ret = get_new_location(rc->data_inode, &new_bytenr, 15855d4f98a2SYan Zheng bytenr, num_bytes); 15863fd0a558SYan, Zheng if (ret > 0) { 15873fd0a558SYan, Zheng WARN_ON(1); 15885d4f98a2SYan Zheng continue; 15893fd0a558SYan, Zheng } 15905d4f98a2SYan Zheng BUG_ON(ret < 0); 15915d4f98a2SYan Zheng 15925d4f98a2SYan Zheng btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); 15935d4f98a2SYan Zheng dirty = 1; 15945d4f98a2SYan Zheng 15955d4f98a2SYan Zheng key.offset -= btrfs_file_extent_offset(leaf, fi); 15965d4f98a2SYan Zheng ret = btrfs_inc_extent_ref(trans, root, new_bytenr, 15975d4f98a2SYan Zheng num_bytes, parent, 15985d4f98a2SYan Zheng btrfs_header_owner(leaf), 15995d4f98a2SYan Zheng key.objectid, key.offset); 16005d4f98a2SYan Zheng BUG_ON(ret); 16015d4f98a2SYan Zheng 16025d4f98a2SYan Zheng ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 16035d4f98a2SYan Zheng parent, btrfs_header_owner(leaf), 16045d4f98a2SYan Zheng key.objectid, key.offset); 16055d4f98a2SYan Zheng BUG_ON(ret); 16065d4f98a2SYan Zheng } 16075d4f98a2SYan Zheng if (dirty) 16085d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 16093fd0a558SYan, Zheng if (inode) 16103fd0a558SYan, Zheng btrfs_add_delayed_iput(inode); 16115d4f98a2SYan Zheng return 0; 16125d4f98a2SYan Zheng } 16135d4f98a2SYan Zheng 16145d4f98a2SYan Zheng static noinline_for_stack 16155d4f98a2SYan Zheng int memcmp_node_keys(struct extent_buffer *eb, int slot, 16165d4f98a2SYan Zheng struct btrfs_path *path, int level) 16175d4f98a2SYan Zheng { 16185d4f98a2SYan Zheng struct btrfs_disk_key key1; 16195d4f98a2SYan Zheng struct btrfs_disk_key key2; 16205d4f98a2SYan Zheng btrfs_node_key(eb, &key1, slot); 16215d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &key2, path->slots[level]); 16225d4f98a2SYan Zheng return memcmp(&key1, &key2, sizeof(key1)); 16235d4f98a2SYan Zheng } 16245d4f98a2SYan Zheng 16255d4f98a2SYan Zheng /* 16265d4f98a2SYan Zheng * try to replace tree blocks in fs tree with the new blocks 16275d4f98a2SYan Zheng * in reloc tree. tree blocks haven't been modified since the 16285d4f98a2SYan Zheng * reloc tree was create can be replaced. 16295d4f98a2SYan Zheng * 16305d4f98a2SYan Zheng * if a block was replaced, level of the block + 1 is returned. 16315d4f98a2SYan Zheng * if no block got replaced, 0 is returned. if there are other 16325d4f98a2SYan Zheng * errors, a negative error number is returned. 16335d4f98a2SYan Zheng */ 16343fd0a558SYan, Zheng static noinline_for_stack 16353fd0a558SYan, Zheng int replace_path(struct btrfs_trans_handle *trans, 16365d4f98a2SYan Zheng struct btrfs_root *dest, struct btrfs_root *src, 16375d4f98a2SYan Zheng struct btrfs_path *path, struct btrfs_key *next_key, 16385d4f98a2SYan Zheng int lowest_level, int max_level) 16395d4f98a2SYan Zheng { 16405d4f98a2SYan Zheng struct extent_buffer *eb; 16415d4f98a2SYan Zheng struct extent_buffer *parent; 16425d4f98a2SYan Zheng struct btrfs_key key; 16435d4f98a2SYan Zheng u64 old_bytenr; 16445d4f98a2SYan Zheng u64 new_bytenr; 16455d4f98a2SYan Zheng u64 old_ptr_gen; 16465d4f98a2SYan Zheng u64 new_ptr_gen; 16475d4f98a2SYan Zheng u64 last_snapshot; 16485d4f98a2SYan Zheng u32 blocksize; 16493fd0a558SYan, Zheng int cow = 0; 16505d4f98a2SYan Zheng int level; 16515d4f98a2SYan Zheng int ret; 16525d4f98a2SYan Zheng int slot; 16535d4f98a2SYan Zheng 16545d4f98a2SYan Zheng BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); 16555d4f98a2SYan Zheng BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); 16565d4f98a2SYan Zheng 16575d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&src->root_item); 16583fd0a558SYan, Zheng again: 16595d4f98a2SYan Zheng slot = path->slots[lowest_level]; 16605d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); 16615d4f98a2SYan Zheng 16625d4f98a2SYan Zheng eb = btrfs_lock_root_node(dest); 16635d4f98a2SYan Zheng btrfs_set_lock_blocking(eb); 16645d4f98a2SYan Zheng level = btrfs_header_level(eb); 16655d4f98a2SYan Zheng 16665d4f98a2SYan Zheng if (level < lowest_level) { 16675d4f98a2SYan Zheng btrfs_tree_unlock(eb); 16685d4f98a2SYan Zheng free_extent_buffer(eb); 16695d4f98a2SYan Zheng return 0; 16705d4f98a2SYan Zheng } 16715d4f98a2SYan Zheng 16723fd0a558SYan, Zheng if (cow) { 16735d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); 16745d4f98a2SYan Zheng BUG_ON(ret); 16753fd0a558SYan, Zheng } 16765d4f98a2SYan Zheng btrfs_set_lock_blocking(eb); 16775d4f98a2SYan Zheng 16785d4f98a2SYan Zheng if (next_key) { 16795d4f98a2SYan Zheng next_key->objectid = (u64)-1; 16805d4f98a2SYan Zheng next_key->type = (u8)-1; 16815d4f98a2SYan Zheng next_key->offset = (u64)-1; 16825d4f98a2SYan Zheng } 16835d4f98a2SYan Zheng 16845d4f98a2SYan Zheng parent = eb; 16855d4f98a2SYan Zheng while (1) { 16865d4f98a2SYan Zheng level = btrfs_header_level(parent); 16875d4f98a2SYan Zheng BUG_ON(level < lowest_level); 16885d4f98a2SYan Zheng 16895d4f98a2SYan Zheng ret = btrfs_bin_search(parent, &key, level, &slot); 16905d4f98a2SYan Zheng if (ret && slot > 0) 16915d4f98a2SYan Zheng slot--; 16925d4f98a2SYan Zheng 16935d4f98a2SYan Zheng if (next_key && slot + 1 < btrfs_header_nritems(parent)) 16945d4f98a2SYan Zheng btrfs_node_key_to_cpu(parent, next_key, slot + 1); 16955d4f98a2SYan Zheng 16965d4f98a2SYan Zheng old_bytenr = btrfs_node_blockptr(parent, slot); 16975d4f98a2SYan Zheng blocksize = btrfs_level_size(dest, level - 1); 16985d4f98a2SYan Zheng old_ptr_gen = btrfs_node_ptr_generation(parent, slot); 16995d4f98a2SYan Zheng 17005d4f98a2SYan Zheng if (level <= max_level) { 17015d4f98a2SYan Zheng eb = path->nodes[level]; 17025d4f98a2SYan Zheng new_bytenr = btrfs_node_blockptr(eb, 17035d4f98a2SYan Zheng path->slots[level]); 17045d4f98a2SYan Zheng new_ptr_gen = btrfs_node_ptr_generation(eb, 17055d4f98a2SYan Zheng path->slots[level]); 17065d4f98a2SYan Zheng } else { 17075d4f98a2SYan Zheng new_bytenr = 0; 17085d4f98a2SYan Zheng new_ptr_gen = 0; 17095d4f98a2SYan Zheng } 17105d4f98a2SYan Zheng 17115d4f98a2SYan Zheng if (new_bytenr > 0 && new_bytenr == old_bytenr) { 17125d4f98a2SYan Zheng WARN_ON(1); 17135d4f98a2SYan Zheng ret = level; 17145d4f98a2SYan Zheng break; 17155d4f98a2SYan Zheng } 17165d4f98a2SYan Zheng 17175d4f98a2SYan Zheng if (new_bytenr == 0 || old_ptr_gen > last_snapshot || 17185d4f98a2SYan Zheng memcmp_node_keys(parent, slot, path, level)) { 17193fd0a558SYan, Zheng if (level <= lowest_level) { 17205d4f98a2SYan Zheng ret = 0; 17215d4f98a2SYan Zheng break; 17225d4f98a2SYan Zheng } 17235d4f98a2SYan Zheng 17245d4f98a2SYan Zheng eb = read_tree_block(dest, old_bytenr, blocksize, 17255d4f98a2SYan Zheng old_ptr_gen); 17265d4f98a2SYan Zheng btrfs_tree_lock(eb); 17273fd0a558SYan, Zheng if (cow) { 17285d4f98a2SYan Zheng ret = btrfs_cow_block(trans, dest, eb, parent, 17295d4f98a2SYan Zheng slot, &eb); 17305d4f98a2SYan Zheng BUG_ON(ret); 17315d4f98a2SYan Zheng } 17323fd0a558SYan, Zheng btrfs_set_lock_blocking(eb); 17335d4f98a2SYan Zheng 17345d4f98a2SYan Zheng btrfs_tree_unlock(parent); 17355d4f98a2SYan Zheng free_extent_buffer(parent); 17365d4f98a2SYan Zheng 17375d4f98a2SYan Zheng parent = eb; 17385d4f98a2SYan Zheng continue; 17395d4f98a2SYan Zheng } 17405d4f98a2SYan Zheng 17413fd0a558SYan, Zheng if (!cow) { 17423fd0a558SYan, Zheng btrfs_tree_unlock(parent); 17433fd0a558SYan, Zheng free_extent_buffer(parent); 17443fd0a558SYan, Zheng cow = 1; 17453fd0a558SYan, Zheng goto again; 17463fd0a558SYan, Zheng } 17473fd0a558SYan, Zheng 17485d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 17495d4f98a2SYan Zheng path->slots[level]); 17505d4f98a2SYan Zheng btrfs_release_path(src, path); 17515d4f98a2SYan Zheng 17525d4f98a2SYan Zheng path->lowest_level = level; 17535d4f98a2SYan Zheng ret = btrfs_search_slot(trans, src, &key, path, 0, 1); 17545d4f98a2SYan Zheng path->lowest_level = 0; 17555d4f98a2SYan Zheng BUG_ON(ret); 17565d4f98a2SYan Zheng 17575d4f98a2SYan Zheng /* 17585d4f98a2SYan Zheng * swap blocks in fs tree and reloc tree. 17595d4f98a2SYan Zheng */ 17605d4f98a2SYan Zheng btrfs_set_node_blockptr(parent, slot, new_bytenr); 17615d4f98a2SYan Zheng btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); 17625d4f98a2SYan Zheng btrfs_mark_buffer_dirty(parent); 17635d4f98a2SYan Zheng 17645d4f98a2SYan Zheng btrfs_set_node_blockptr(path->nodes[level], 17655d4f98a2SYan Zheng path->slots[level], old_bytenr); 17665d4f98a2SYan Zheng btrfs_set_node_ptr_generation(path->nodes[level], 17675d4f98a2SYan Zheng path->slots[level], old_ptr_gen); 17685d4f98a2SYan Zheng btrfs_mark_buffer_dirty(path->nodes[level]); 17695d4f98a2SYan Zheng 17705d4f98a2SYan Zheng ret = btrfs_inc_extent_ref(trans, src, old_bytenr, blocksize, 17715d4f98a2SYan Zheng path->nodes[level]->start, 17725d4f98a2SYan Zheng src->root_key.objectid, level - 1, 0); 17735d4f98a2SYan Zheng BUG_ON(ret); 17745d4f98a2SYan Zheng ret = btrfs_inc_extent_ref(trans, dest, new_bytenr, blocksize, 17755d4f98a2SYan Zheng 0, dest->root_key.objectid, level - 1, 17765d4f98a2SYan Zheng 0); 17775d4f98a2SYan Zheng BUG_ON(ret); 17785d4f98a2SYan Zheng 17795d4f98a2SYan Zheng ret = btrfs_free_extent(trans, src, new_bytenr, blocksize, 17805d4f98a2SYan Zheng path->nodes[level]->start, 17815d4f98a2SYan Zheng src->root_key.objectid, level - 1, 0); 17825d4f98a2SYan Zheng BUG_ON(ret); 17835d4f98a2SYan Zheng 17845d4f98a2SYan Zheng ret = btrfs_free_extent(trans, dest, old_bytenr, blocksize, 17855d4f98a2SYan Zheng 0, dest->root_key.objectid, level - 1, 17865d4f98a2SYan Zheng 0); 17875d4f98a2SYan Zheng BUG_ON(ret); 17885d4f98a2SYan Zheng 17895d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 17905d4f98a2SYan Zheng 17915d4f98a2SYan Zheng ret = level; 17925d4f98a2SYan Zheng break; 17935d4f98a2SYan Zheng } 17945d4f98a2SYan Zheng btrfs_tree_unlock(parent); 17955d4f98a2SYan Zheng free_extent_buffer(parent); 17965d4f98a2SYan Zheng return ret; 17975d4f98a2SYan Zheng } 17985d4f98a2SYan Zheng 17995d4f98a2SYan Zheng /* 18005d4f98a2SYan Zheng * helper to find next relocated block in reloc tree 18015d4f98a2SYan Zheng */ 18025d4f98a2SYan Zheng static noinline_for_stack 18035d4f98a2SYan Zheng int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 18045d4f98a2SYan Zheng int *level) 18055d4f98a2SYan Zheng { 18065d4f98a2SYan Zheng struct extent_buffer *eb; 18075d4f98a2SYan Zheng int i; 18085d4f98a2SYan Zheng u64 last_snapshot; 18095d4f98a2SYan Zheng u32 nritems; 18105d4f98a2SYan Zheng 18115d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 18125d4f98a2SYan Zheng 18135d4f98a2SYan Zheng for (i = 0; i < *level; i++) { 18145d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 18155d4f98a2SYan Zheng path->nodes[i] = NULL; 18165d4f98a2SYan Zheng } 18175d4f98a2SYan Zheng 18185d4f98a2SYan Zheng for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { 18195d4f98a2SYan Zheng eb = path->nodes[i]; 18205d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 18215d4f98a2SYan Zheng while (path->slots[i] + 1 < nritems) { 18225d4f98a2SYan Zheng path->slots[i]++; 18235d4f98a2SYan Zheng if (btrfs_node_ptr_generation(eb, path->slots[i]) <= 18245d4f98a2SYan Zheng last_snapshot) 18255d4f98a2SYan Zheng continue; 18265d4f98a2SYan Zheng 18275d4f98a2SYan Zheng *level = i; 18285d4f98a2SYan Zheng return 0; 18295d4f98a2SYan Zheng } 18305d4f98a2SYan Zheng free_extent_buffer(path->nodes[i]); 18315d4f98a2SYan Zheng path->nodes[i] = NULL; 18325d4f98a2SYan Zheng } 18335d4f98a2SYan Zheng return 1; 18345d4f98a2SYan Zheng } 18355d4f98a2SYan Zheng 18365d4f98a2SYan Zheng /* 18375d4f98a2SYan Zheng * walk down reloc tree to find relocated block of lowest level 18385d4f98a2SYan Zheng */ 18395d4f98a2SYan Zheng static noinline_for_stack 18405d4f98a2SYan Zheng int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, 18415d4f98a2SYan Zheng int *level) 18425d4f98a2SYan Zheng { 18435d4f98a2SYan Zheng struct extent_buffer *eb = NULL; 18445d4f98a2SYan Zheng int i; 18455d4f98a2SYan Zheng u64 bytenr; 18465d4f98a2SYan Zheng u64 ptr_gen = 0; 18475d4f98a2SYan Zheng u64 last_snapshot; 18485d4f98a2SYan Zheng u32 blocksize; 18495d4f98a2SYan Zheng u32 nritems; 18505d4f98a2SYan Zheng 18515d4f98a2SYan Zheng last_snapshot = btrfs_root_last_snapshot(&root->root_item); 18525d4f98a2SYan Zheng 18535d4f98a2SYan Zheng for (i = *level; i > 0; i--) { 18545d4f98a2SYan Zheng eb = path->nodes[i]; 18555d4f98a2SYan Zheng nritems = btrfs_header_nritems(eb); 18565d4f98a2SYan Zheng while (path->slots[i] < nritems) { 18575d4f98a2SYan Zheng ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); 18585d4f98a2SYan Zheng if (ptr_gen > last_snapshot) 18595d4f98a2SYan Zheng break; 18605d4f98a2SYan Zheng path->slots[i]++; 18615d4f98a2SYan Zheng } 18625d4f98a2SYan Zheng if (path->slots[i] >= nritems) { 18635d4f98a2SYan Zheng if (i == *level) 18645d4f98a2SYan Zheng break; 18655d4f98a2SYan Zheng *level = i + 1; 18665d4f98a2SYan Zheng return 0; 18675d4f98a2SYan Zheng } 18685d4f98a2SYan Zheng if (i == 1) { 18695d4f98a2SYan Zheng *level = i; 18705d4f98a2SYan Zheng return 0; 18715d4f98a2SYan Zheng } 18725d4f98a2SYan Zheng 18735d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(eb, path->slots[i]); 18745d4f98a2SYan Zheng blocksize = btrfs_level_size(root, i - 1); 18755d4f98a2SYan Zheng eb = read_tree_block(root, bytenr, blocksize, ptr_gen); 18765d4f98a2SYan Zheng BUG_ON(btrfs_header_level(eb) != i - 1); 18775d4f98a2SYan Zheng path->nodes[i - 1] = eb; 18785d4f98a2SYan Zheng path->slots[i - 1] = 0; 18795d4f98a2SYan Zheng } 18805d4f98a2SYan Zheng return 1; 18815d4f98a2SYan Zheng } 18825d4f98a2SYan Zheng 18835d4f98a2SYan Zheng /* 18845d4f98a2SYan Zheng * invalidate extent cache for file extents whose key in range of 18855d4f98a2SYan Zheng * [min_key, max_key) 18865d4f98a2SYan Zheng */ 18875d4f98a2SYan Zheng static int invalidate_extent_cache(struct btrfs_root *root, 18885d4f98a2SYan Zheng struct btrfs_key *min_key, 18895d4f98a2SYan Zheng struct btrfs_key *max_key) 18905d4f98a2SYan Zheng { 18915d4f98a2SYan Zheng struct inode *inode = NULL; 18925d4f98a2SYan Zheng u64 objectid; 18935d4f98a2SYan Zheng u64 start, end; 18945d4f98a2SYan Zheng 18955d4f98a2SYan Zheng objectid = min_key->objectid; 18965d4f98a2SYan Zheng while (1) { 18975d4f98a2SYan Zheng cond_resched(); 18985d4f98a2SYan Zheng iput(inode); 18995d4f98a2SYan Zheng 19005d4f98a2SYan Zheng if (objectid > max_key->objectid) 19015d4f98a2SYan Zheng break; 19025d4f98a2SYan Zheng 19035d4f98a2SYan Zheng inode = find_next_inode(root, objectid); 19045d4f98a2SYan Zheng if (!inode) 19055d4f98a2SYan Zheng break; 19065d4f98a2SYan Zheng 19075d4f98a2SYan Zheng if (inode->i_ino > max_key->objectid) { 19085d4f98a2SYan Zheng iput(inode); 19095d4f98a2SYan Zheng break; 19105d4f98a2SYan Zheng } 19115d4f98a2SYan Zheng 19125d4f98a2SYan Zheng objectid = inode->i_ino + 1; 19135d4f98a2SYan Zheng if (!S_ISREG(inode->i_mode)) 19145d4f98a2SYan Zheng continue; 19155d4f98a2SYan Zheng 19165d4f98a2SYan Zheng if (unlikely(min_key->objectid == inode->i_ino)) { 19175d4f98a2SYan Zheng if (min_key->type > BTRFS_EXTENT_DATA_KEY) 19185d4f98a2SYan Zheng continue; 19195d4f98a2SYan Zheng if (min_key->type < BTRFS_EXTENT_DATA_KEY) 19205d4f98a2SYan Zheng start = 0; 19215d4f98a2SYan Zheng else { 19225d4f98a2SYan Zheng start = min_key->offset; 19235d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(start, root->sectorsize)); 19245d4f98a2SYan Zheng } 19255d4f98a2SYan Zheng } else { 19265d4f98a2SYan Zheng start = 0; 19275d4f98a2SYan Zheng } 19285d4f98a2SYan Zheng 19295d4f98a2SYan Zheng if (unlikely(max_key->objectid == inode->i_ino)) { 19305d4f98a2SYan Zheng if (max_key->type < BTRFS_EXTENT_DATA_KEY) 19315d4f98a2SYan Zheng continue; 19325d4f98a2SYan Zheng if (max_key->type > BTRFS_EXTENT_DATA_KEY) { 19335d4f98a2SYan Zheng end = (u64)-1; 19345d4f98a2SYan Zheng } else { 19355d4f98a2SYan Zheng if (max_key->offset == 0) 19365d4f98a2SYan Zheng continue; 19375d4f98a2SYan Zheng end = max_key->offset; 19385d4f98a2SYan Zheng WARN_ON(!IS_ALIGNED(end, root->sectorsize)); 19395d4f98a2SYan Zheng end--; 19405d4f98a2SYan Zheng } 19415d4f98a2SYan Zheng } else { 19425d4f98a2SYan Zheng end = (u64)-1; 19435d4f98a2SYan Zheng } 19445d4f98a2SYan Zheng 19455d4f98a2SYan Zheng /* the lock_extent waits for readpage to complete */ 19465d4f98a2SYan Zheng lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); 19475d4f98a2SYan Zheng btrfs_drop_extent_cache(inode, start, end, 1); 19485d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); 19495d4f98a2SYan Zheng } 19505d4f98a2SYan Zheng return 0; 19515d4f98a2SYan Zheng } 19525d4f98a2SYan Zheng 19535d4f98a2SYan Zheng static int find_next_key(struct btrfs_path *path, int level, 19545d4f98a2SYan Zheng struct btrfs_key *key) 19555d4f98a2SYan Zheng 19565d4f98a2SYan Zheng { 19575d4f98a2SYan Zheng while (level < BTRFS_MAX_LEVEL) { 19585d4f98a2SYan Zheng if (!path->nodes[level]) 19595d4f98a2SYan Zheng break; 19605d4f98a2SYan Zheng if (path->slots[level] + 1 < 19615d4f98a2SYan Zheng btrfs_header_nritems(path->nodes[level])) { 19625d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], key, 19635d4f98a2SYan Zheng path->slots[level] + 1); 19645d4f98a2SYan Zheng return 0; 19655d4f98a2SYan Zheng } 19665d4f98a2SYan Zheng level++; 19675d4f98a2SYan Zheng } 19685d4f98a2SYan Zheng return 1; 19695d4f98a2SYan Zheng } 19705d4f98a2SYan Zheng 19715d4f98a2SYan Zheng /* 19725d4f98a2SYan Zheng * merge the relocated tree blocks in reloc tree with corresponding 19735d4f98a2SYan Zheng * fs tree. 19745d4f98a2SYan Zheng */ 19755d4f98a2SYan Zheng static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, 19765d4f98a2SYan Zheng struct btrfs_root *root) 19775d4f98a2SYan Zheng { 19785d4f98a2SYan Zheng LIST_HEAD(inode_list); 19795d4f98a2SYan Zheng struct btrfs_key key; 19805d4f98a2SYan Zheng struct btrfs_key next_key; 19815d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 19825d4f98a2SYan Zheng struct btrfs_root *reloc_root; 19835d4f98a2SYan Zheng struct btrfs_root_item *root_item; 19845d4f98a2SYan Zheng struct btrfs_path *path; 19853fd0a558SYan, Zheng struct extent_buffer *leaf; 19865d4f98a2SYan Zheng unsigned long nr; 19875d4f98a2SYan Zheng int level; 19885d4f98a2SYan Zheng int max_level; 19895d4f98a2SYan Zheng int replaced = 0; 19905d4f98a2SYan Zheng int ret; 19915d4f98a2SYan Zheng int err = 0; 19923fd0a558SYan, Zheng u32 min_reserved; 19935d4f98a2SYan Zheng 19945d4f98a2SYan Zheng path = btrfs_alloc_path(); 19955d4f98a2SYan Zheng if (!path) 19965d4f98a2SYan Zheng return -ENOMEM; 19975d4f98a2SYan Zheng 19985d4f98a2SYan Zheng reloc_root = root->reloc_root; 19995d4f98a2SYan Zheng root_item = &reloc_root->root_item; 20005d4f98a2SYan Zheng 20015d4f98a2SYan Zheng if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { 20025d4f98a2SYan Zheng level = btrfs_root_level(root_item); 20035d4f98a2SYan Zheng extent_buffer_get(reloc_root->node); 20045d4f98a2SYan Zheng path->nodes[level] = reloc_root->node; 20055d4f98a2SYan Zheng path->slots[level] = 0; 20065d4f98a2SYan Zheng } else { 20075d4f98a2SYan Zheng btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); 20085d4f98a2SYan Zheng 20095d4f98a2SYan Zheng level = root_item->drop_level; 20105d4f98a2SYan Zheng BUG_ON(level == 0); 20115d4f98a2SYan Zheng path->lowest_level = level; 20125d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); 201333c66f43SYan Zheng path->lowest_level = 0; 20145d4f98a2SYan Zheng if (ret < 0) { 20155d4f98a2SYan Zheng btrfs_free_path(path); 20165d4f98a2SYan Zheng return ret; 20175d4f98a2SYan Zheng } 20185d4f98a2SYan Zheng 20195d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &next_key, 20205d4f98a2SYan Zheng path->slots[level]); 20215d4f98a2SYan Zheng WARN_ON(memcmp(&key, &next_key, sizeof(key))); 20225d4f98a2SYan Zheng 20235d4f98a2SYan Zheng btrfs_unlock_up_safe(path, 0); 20245d4f98a2SYan Zheng } 20255d4f98a2SYan Zheng 20263fd0a558SYan, Zheng min_reserved = root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 20275d4f98a2SYan Zheng memset(&next_key, 0, sizeof(next_key)); 20285d4f98a2SYan Zheng 20295d4f98a2SYan Zheng while (1) { 2030a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 0); 203198d5dc13STsutomu Itoh BUG_ON(IS_ERR(trans)); 20323fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 20333fd0a558SYan, Zheng 20343fd0a558SYan, Zheng ret = btrfs_block_rsv_check(trans, root, rc->block_rsv, 20353fd0a558SYan, Zheng min_reserved, 0); 20363fd0a558SYan, Zheng if (ret) { 20373fd0a558SYan, Zheng BUG_ON(ret != -EAGAIN); 20383fd0a558SYan, Zheng ret = btrfs_commit_transaction(trans, root); 20393fd0a558SYan, Zheng BUG_ON(ret); 20403fd0a558SYan, Zheng continue; 20413fd0a558SYan, Zheng } 20423fd0a558SYan, Zheng 20433fd0a558SYan, Zheng replaced = 0; 20445d4f98a2SYan Zheng max_level = level; 20455d4f98a2SYan Zheng 20465d4f98a2SYan Zheng ret = walk_down_reloc_tree(reloc_root, path, &level); 20475d4f98a2SYan Zheng if (ret < 0) { 20485d4f98a2SYan Zheng err = ret; 20495d4f98a2SYan Zheng goto out; 20505d4f98a2SYan Zheng } 20515d4f98a2SYan Zheng if (ret > 0) 20525d4f98a2SYan Zheng break; 20535d4f98a2SYan Zheng 20545d4f98a2SYan Zheng if (!find_next_key(path, level, &key) && 20555d4f98a2SYan Zheng btrfs_comp_cpu_keys(&next_key, &key) >= 0) { 20565d4f98a2SYan Zheng ret = 0; 20575d4f98a2SYan Zheng } else { 20583fd0a558SYan, Zheng ret = replace_path(trans, root, reloc_root, path, 20593fd0a558SYan, Zheng &next_key, level, max_level); 20605d4f98a2SYan Zheng } 20615d4f98a2SYan Zheng if (ret < 0) { 20625d4f98a2SYan Zheng err = ret; 20635d4f98a2SYan Zheng goto out; 20645d4f98a2SYan Zheng } 20655d4f98a2SYan Zheng 20665d4f98a2SYan Zheng if (ret > 0) { 20675d4f98a2SYan Zheng level = ret; 20685d4f98a2SYan Zheng btrfs_node_key_to_cpu(path->nodes[level], &key, 20695d4f98a2SYan Zheng path->slots[level]); 20705d4f98a2SYan Zheng replaced = 1; 20715d4f98a2SYan Zheng } 20725d4f98a2SYan Zheng 20735d4f98a2SYan Zheng ret = walk_up_reloc_tree(reloc_root, path, &level); 20745d4f98a2SYan Zheng if (ret > 0) 20755d4f98a2SYan Zheng break; 20765d4f98a2SYan Zheng 20775d4f98a2SYan Zheng BUG_ON(level == 0); 20785d4f98a2SYan Zheng /* 20795d4f98a2SYan Zheng * save the merging progress in the drop_progress. 20805d4f98a2SYan Zheng * this is OK since root refs == 1 in this case. 20815d4f98a2SYan Zheng */ 20825d4f98a2SYan Zheng btrfs_node_key(path->nodes[level], &root_item->drop_progress, 20835d4f98a2SYan Zheng path->slots[level]); 20845d4f98a2SYan Zheng root_item->drop_level = level; 20855d4f98a2SYan Zheng 20865d4f98a2SYan Zheng nr = trans->blocks_used; 20873fd0a558SYan, Zheng btrfs_end_transaction_throttle(trans, root); 20885d4f98a2SYan Zheng 20895d4f98a2SYan Zheng btrfs_btree_balance_dirty(root, nr); 20905d4f98a2SYan Zheng 20915d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 20925d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 20935d4f98a2SYan Zheng } 20945d4f98a2SYan Zheng 20955d4f98a2SYan Zheng /* 20965d4f98a2SYan Zheng * handle the case only one block in the fs tree need to be 20975d4f98a2SYan Zheng * relocated and the block is tree root. 20985d4f98a2SYan Zheng */ 20995d4f98a2SYan Zheng leaf = btrfs_lock_root_node(root); 21005d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); 21015d4f98a2SYan Zheng btrfs_tree_unlock(leaf); 21025d4f98a2SYan Zheng free_extent_buffer(leaf); 21035d4f98a2SYan Zheng if (ret < 0) 21045d4f98a2SYan Zheng err = ret; 21055d4f98a2SYan Zheng out: 21065d4f98a2SYan Zheng btrfs_free_path(path); 21075d4f98a2SYan Zheng 21085d4f98a2SYan Zheng if (err == 0) { 21095d4f98a2SYan Zheng memset(&root_item->drop_progress, 0, 21105d4f98a2SYan Zheng sizeof(root_item->drop_progress)); 21115d4f98a2SYan Zheng root_item->drop_level = 0; 21125d4f98a2SYan Zheng btrfs_set_root_refs(root_item, 0); 21133fd0a558SYan, Zheng btrfs_update_reloc_root(trans, root); 21145d4f98a2SYan Zheng } 21155d4f98a2SYan Zheng 21165d4f98a2SYan Zheng nr = trans->blocks_used; 21173fd0a558SYan, Zheng btrfs_end_transaction_throttle(trans, root); 21185d4f98a2SYan Zheng 21195d4f98a2SYan Zheng btrfs_btree_balance_dirty(root, nr); 21205d4f98a2SYan Zheng 21215d4f98a2SYan Zheng if (replaced && rc->stage == UPDATE_DATA_PTRS) 21225d4f98a2SYan Zheng invalidate_extent_cache(root, &key, &next_key); 21235d4f98a2SYan Zheng 21245d4f98a2SYan Zheng return err; 21255d4f98a2SYan Zheng } 21265d4f98a2SYan Zheng 21273fd0a558SYan, Zheng static noinline_for_stack 21283fd0a558SYan, Zheng int prepare_to_merge(struct reloc_control *rc, int err) 21295d4f98a2SYan Zheng { 21303fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 21313fd0a558SYan, Zheng struct btrfs_root *reloc_root; 21325d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 21333fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 21343fd0a558SYan, Zheng u64 num_bytes = 0; 21353fd0a558SYan, Zheng int ret; 21363fd0a558SYan, Zheng 21373fd0a558SYan, Zheng mutex_lock(&root->fs_info->trans_mutex); 21383fd0a558SYan, Zheng rc->merging_rsv_size += root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; 21393fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated * 2; 21403fd0a558SYan, Zheng mutex_unlock(&root->fs_info->trans_mutex); 21413fd0a558SYan, Zheng again: 21423fd0a558SYan, Zheng if (!err) { 21433fd0a558SYan, Zheng num_bytes = rc->merging_rsv_size; 21443fd0a558SYan, Zheng ret = btrfs_block_rsv_add(NULL, root, rc->block_rsv, 21458bb8ab2eSJosef Bacik num_bytes); 21463fd0a558SYan, Zheng if (ret) 21473fd0a558SYan, Zheng err = ret; 21483fd0a558SYan, Zheng } 21493fd0a558SYan, Zheng 21503fd0a558SYan, Zheng trans = btrfs_join_transaction(rc->extent_root, 1); 21513612b495STsutomu Itoh if (IS_ERR(trans)) { 21523612b495STsutomu Itoh if (!err) 21533612b495STsutomu Itoh btrfs_block_rsv_release(rc->extent_root, 21543612b495STsutomu Itoh rc->block_rsv, num_bytes); 21553612b495STsutomu Itoh return PTR_ERR(trans); 21563612b495STsutomu Itoh } 21573fd0a558SYan, Zheng 21583fd0a558SYan, Zheng if (!err) { 21593fd0a558SYan, Zheng if (num_bytes != rc->merging_rsv_size) { 21603fd0a558SYan, Zheng btrfs_end_transaction(trans, rc->extent_root); 21613fd0a558SYan, Zheng btrfs_block_rsv_release(rc->extent_root, 21623fd0a558SYan, Zheng rc->block_rsv, num_bytes); 21633fd0a558SYan, Zheng goto again; 21643fd0a558SYan, Zheng } 21653fd0a558SYan, Zheng } 21663fd0a558SYan, Zheng 21673fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 21683fd0a558SYan, Zheng 21693fd0a558SYan, Zheng while (!list_empty(&rc->reloc_roots)) { 21703fd0a558SYan, Zheng reloc_root = list_entry(rc->reloc_roots.next, 21713fd0a558SYan, Zheng struct btrfs_root, root_list); 21723fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 21733fd0a558SYan, Zheng 21743fd0a558SYan, Zheng root = read_fs_root(reloc_root->fs_info, 21753fd0a558SYan, Zheng reloc_root->root_key.offset); 21763fd0a558SYan, Zheng BUG_ON(IS_ERR(root)); 21773fd0a558SYan, Zheng BUG_ON(root->reloc_root != reloc_root); 21783fd0a558SYan, Zheng 21793fd0a558SYan, Zheng /* 21803fd0a558SYan, Zheng * set reference count to 1, so btrfs_recover_relocation 21813fd0a558SYan, Zheng * knows it should resumes merging 21823fd0a558SYan, Zheng */ 21833fd0a558SYan, Zheng if (!err) 21843fd0a558SYan, Zheng btrfs_set_root_refs(&reloc_root->root_item, 1); 21853fd0a558SYan, Zheng btrfs_update_reloc_root(trans, root); 21863fd0a558SYan, Zheng 21873fd0a558SYan, Zheng list_add(&reloc_root->root_list, &reloc_roots); 21883fd0a558SYan, Zheng } 21893fd0a558SYan, Zheng 21903fd0a558SYan, Zheng list_splice(&reloc_roots, &rc->reloc_roots); 21913fd0a558SYan, Zheng 21923fd0a558SYan, Zheng if (!err) 21933fd0a558SYan, Zheng btrfs_commit_transaction(trans, rc->extent_root); 21943fd0a558SYan, Zheng else 21953fd0a558SYan, Zheng btrfs_end_transaction(trans, rc->extent_root); 21963fd0a558SYan, Zheng return err; 21973fd0a558SYan, Zheng } 21983fd0a558SYan, Zheng 21993fd0a558SYan, Zheng static noinline_for_stack 22003fd0a558SYan, Zheng int merge_reloc_roots(struct reloc_control *rc) 22013fd0a558SYan, Zheng { 22025d4f98a2SYan Zheng struct btrfs_root *root; 22035d4f98a2SYan Zheng struct btrfs_root *reloc_root; 22043fd0a558SYan, Zheng LIST_HEAD(reloc_roots); 22053fd0a558SYan, Zheng int found = 0; 22063fd0a558SYan, Zheng int ret; 22073fd0a558SYan, Zheng again: 22083fd0a558SYan, Zheng root = rc->extent_root; 22093fd0a558SYan, Zheng mutex_lock(&root->fs_info->trans_mutex); 22103fd0a558SYan, Zheng list_splice_init(&rc->reloc_roots, &reloc_roots); 22113fd0a558SYan, Zheng mutex_unlock(&root->fs_info->trans_mutex); 22125d4f98a2SYan Zheng 22133fd0a558SYan, Zheng while (!list_empty(&reloc_roots)) { 22143fd0a558SYan, Zheng found = 1; 22153fd0a558SYan, Zheng reloc_root = list_entry(reloc_roots.next, 22163fd0a558SYan, Zheng struct btrfs_root, root_list); 22175d4f98a2SYan Zheng 22185d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 22195d4f98a2SYan Zheng root = read_fs_root(reloc_root->fs_info, 22205d4f98a2SYan Zheng reloc_root->root_key.offset); 22215d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 22225d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 22235d4f98a2SYan Zheng 22243fd0a558SYan, Zheng ret = merge_reloc_root(rc, root); 22253fd0a558SYan, Zheng BUG_ON(ret); 22263fd0a558SYan, Zheng } else { 22273fd0a558SYan, Zheng list_del_init(&reloc_root->root_list); 22283fd0a558SYan, Zheng } 22293fd0a558SYan, Zheng btrfs_drop_snapshot(reloc_root, rc->block_rsv, 0); 22305d4f98a2SYan Zheng } 22315d4f98a2SYan Zheng 22323fd0a558SYan, Zheng if (found) { 22333fd0a558SYan, Zheng found = 0; 22343fd0a558SYan, Zheng goto again; 22355d4f98a2SYan Zheng } 22365d4f98a2SYan Zheng BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); 22375d4f98a2SYan Zheng return 0; 22385d4f98a2SYan Zheng } 22395d4f98a2SYan Zheng 22405d4f98a2SYan Zheng static void free_block_list(struct rb_root *blocks) 22415d4f98a2SYan Zheng { 22425d4f98a2SYan Zheng struct tree_block *block; 22435d4f98a2SYan Zheng struct rb_node *rb_node; 22445d4f98a2SYan Zheng while ((rb_node = rb_first(blocks))) { 22455d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 22465d4f98a2SYan Zheng rb_erase(rb_node, blocks); 22475d4f98a2SYan Zheng kfree(block); 22485d4f98a2SYan Zheng } 22495d4f98a2SYan Zheng } 22505d4f98a2SYan Zheng 22515d4f98a2SYan Zheng static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, 22525d4f98a2SYan Zheng struct btrfs_root *reloc_root) 22535d4f98a2SYan Zheng { 22545d4f98a2SYan Zheng struct btrfs_root *root; 22555d4f98a2SYan Zheng 22565d4f98a2SYan Zheng if (reloc_root->last_trans == trans->transid) 22575d4f98a2SYan Zheng return 0; 22585d4f98a2SYan Zheng 22595d4f98a2SYan Zheng root = read_fs_root(reloc_root->fs_info, reloc_root->root_key.offset); 22605d4f98a2SYan Zheng BUG_ON(IS_ERR(root)); 22615d4f98a2SYan Zheng BUG_ON(root->reloc_root != reloc_root); 22625d4f98a2SYan Zheng 22635d4f98a2SYan Zheng return btrfs_record_root_in_trans(trans, root); 22645d4f98a2SYan Zheng } 22655d4f98a2SYan Zheng 22663fd0a558SYan, Zheng static noinline_for_stack 22673fd0a558SYan, Zheng struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, 22683fd0a558SYan, Zheng struct reloc_control *rc, 22695d4f98a2SYan Zheng struct backref_node *node, 22703fd0a558SYan, Zheng struct backref_edge *edges[], int *nr) 22715d4f98a2SYan Zheng { 22725d4f98a2SYan Zheng struct backref_node *next; 22735d4f98a2SYan Zheng struct btrfs_root *root; 22743fd0a558SYan, Zheng int index = 0; 22753fd0a558SYan, Zheng 22765d4f98a2SYan Zheng next = node; 22775d4f98a2SYan Zheng while (1) { 22785d4f98a2SYan Zheng cond_resched(); 22795d4f98a2SYan Zheng next = walk_up_backref(next, edges, &index); 22805d4f98a2SYan Zheng root = next->root; 22813fd0a558SYan, Zheng BUG_ON(!root); 22823fd0a558SYan, Zheng BUG_ON(!root->ref_cows); 22835d4f98a2SYan Zheng 22845d4f98a2SYan Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { 22855d4f98a2SYan Zheng record_reloc_root_in_trans(trans, root); 22865d4f98a2SYan Zheng break; 22875d4f98a2SYan Zheng } 22885d4f98a2SYan Zheng 22895d4f98a2SYan Zheng btrfs_record_root_in_trans(trans, root); 22903fd0a558SYan, Zheng root = root->reloc_root; 22913fd0a558SYan, Zheng 22923fd0a558SYan, Zheng if (next->new_bytenr != root->node->start) { 22933fd0a558SYan, Zheng BUG_ON(next->new_bytenr); 22943fd0a558SYan, Zheng BUG_ON(!list_empty(&next->list)); 22953fd0a558SYan, Zheng next->new_bytenr = root->node->start; 22963fd0a558SYan, Zheng next->root = root; 22973fd0a558SYan, Zheng list_add_tail(&next->list, 22983fd0a558SYan, Zheng &rc->backref_cache.changed); 22993fd0a558SYan, Zheng __mark_block_processed(rc, next); 23005d4f98a2SYan Zheng break; 23015d4f98a2SYan Zheng } 23025d4f98a2SYan Zheng 23033fd0a558SYan, Zheng WARN_ON(1); 23045d4f98a2SYan Zheng root = NULL; 23055d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 23065d4f98a2SYan Zheng if (!next || next->level <= node->level) 23075d4f98a2SYan Zheng break; 23085d4f98a2SYan Zheng } 23093fd0a558SYan, Zheng if (!root) 23103fd0a558SYan, Zheng return NULL; 23115d4f98a2SYan Zheng 23125d4f98a2SYan Zheng *nr = index; 23133fd0a558SYan, Zheng next = node; 23143fd0a558SYan, Zheng /* setup backref node path for btrfs_reloc_cow_block */ 23153fd0a558SYan, Zheng while (1) { 23163fd0a558SYan, Zheng rc->backref_cache.path[next->level] = next; 23173fd0a558SYan, Zheng if (--index < 0) 23183fd0a558SYan, Zheng break; 23193fd0a558SYan, Zheng next = edges[index]->node[UPPER]; 23203fd0a558SYan, Zheng } 23215d4f98a2SYan Zheng return root; 23225d4f98a2SYan Zheng } 23235d4f98a2SYan Zheng 23243fd0a558SYan, Zheng /* 23253fd0a558SYan, Zheng * select a tree root for relocation. return NULL if the block 23263fd0a558SYan, Zheng * is reference counted. we should use do_relocation() in this 23273fd0a558SYan, Zheng * case. return a tree root pointer if the block isn't reference 23283fd0a558SYan, Zheng * counted. return -ENOENT if the block is root of reloc tree. 23293fd0a558SYan, Zheng */ 23305d4f98a2SYan Zheng static noinline_for_stack 23315d4f98a2SYan Zheng struct btrfs_root *select_one_root(struct btrfs_trans_handle *trans, 23325d4f98a2SYan Zheng struct backref_node *node) 23335d4f98a2SYan Zheng { 23343fd0a558SYan, Zheng struct backref_node *next; 23353fd0a558SYan, Zheng struct btrfs_root *root; 23363fd0a558SYan, Zheng struct btrfs_root *fs_root = NULL; 23375d4f98a2SYan Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 23383fd0a558SYan, Zheng int index = 0; 23393fd0a558SYan, Zheng 23403fd0a558SYan, Zheng next = node; 23413fd0a558SYan, Zheng while (1) { 23423fd0a558SYan, Zheng cond_resched(); 23433fd0a558SYan, Zheng next = walk_up_backref(next, edges, &index); 23443fd0a558SYan, Zheng root = next->root; 23453fd0a558SYan, Zheng BUG_ON(!root); 23463fd0a558SYan, Zheng 23473fd0a558SYan, Zheng /* no other choice for non-refernce counted tree */ 23483fd0a558SYan, Zheng if (!root->ref_cows) 23493fd0a558SYan, Zheng return root; 23503fd0a558SYan, Zheng 23513fd0a558SYan, Zheng if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) 23523fd0a558SYan, Zheng fs_root = root; 23533fd0a558SYan, Zheng 23543fd0a558SYan, Zheng if (next != node) 23553fd0a558SYan, Zheng return NULL; 23563fd0a558SYan, Zheng 23573fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 23583fd0a558SYan, Zheng if (!next || next->level <= node->level) 23593fd0a558SYan, Zheng break; 23603fd0a558SYan, Zheng } 23613fd0a558SYan, Zheng 23623fd0a558SYan, Zheng if (!fs_root) 23633fd0a558SYan, Zheng return ERR_PTR(-ENOENT); 23643fd0a558SYan, Zheng return fs_root; 23655d4f98a2SYan Zheng } 23665d4f98a2SYan Zheng 23675d4f98a2SYan Zheng static noinline_for_stack 23683fd0a558SYan, Zheng u64 calcu_metadata_size(struct reloc_control *rc, 23693fd0a558SYan, Zheng struct backref_node *node, int reserve) 23705d4f98a2SYan Zheng { 23713fd0a558SYan, Zheng struct backref_node *next = node; 23723fd0a558SYan, Zheng struct backref_edge *edge; 23733fd0a558SYan, Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 23743fd0a558SYan, Zheng u64 num_bytes = 0; 23753fd0a558SYan, Zheng int index = 0; 23765d4f98a2SYan Zheng 23773fd0a558SYan, Zheng BUG_ON(reserve && node->processed); 23783fd0a558SYan, Zheng 23793fd0a558SYan, Zheng while (next) { 23803fd0a558SYan, Zheng cond_resched(); 23815d4f98a2SYan Zheng while (1) { 23823fd0a558SYan, Zheng if (next->processed && (reserve || next != node)) 23835d4f98a2SYan Zheng break; 23845d4f98a2SYan Zheng 23853fd0a558SYan, Zheng num_bytes += btrfs_level_size(rc->extent_root, 23863fd0a558SYan, Zheng next->level); 23873fd0a558SYan, Zheng 23883fd0a558SYan, Zheng if (list_empty(&next->upper)) 23893fd0a558SYan, Zheng break; 23903fd0a558SYan, Zheng 23913fd0a558SYan, Zheng edge = list_entry(next->upper.next, 23923fd0a558SYan, Zheng struct backref_edge, list[LOWER]); 23933fd0a558SYan, Zheng edges[index++] = edge; 23943fd0a558SYan, Zheng next = edge->node[UPPER]; 23955d4f98a2SYan Zheng } 23963fd0a558SYan, Zheng next = walk_down_backref(edges, &index); 23973fd0a558SYan, Zheng } 23983fd0a558SYan, Zheng return num_bytes; 23993fd0a558SYan, Zheng } 24003fd0a558SYan, Zheng 24013fd0a558SYan, Zheng static int reserve_metadata_space(struct btrfs_trans_handle *trans, 24023fd0a558SYan, Zheng struct reloc_control *rc, 24033fd0a558SYan, Zheng struct backref_node *node) 24043fd0a558SYan, Zheng { 24053fd0a558SYan, Zheng struct btrfs_root *root = rc->extent_root; 24063fd0a558SYan, Zheng u64 num_bytes; 24073fd0a558SYan, Zheng int ret; 24083fd0a558SYan, Zheng 24093fd0a558SYan, Zheng num_bytes = calcu_metadata_size(rc, node, 1) * 2; 24103fd0a558SYan, Zheng 24113fd0a558SYan, Zheng trans->block_rsv = rc->block_rsv; 24128bb8ab2eSJosef Bacik ret = btrfs_block_rsv_add(trans, root, rc->block_rsv, num_bytes); 24133fd0a558SYan, Zheng if (ret) { 24143fd0a558SYan, Zheng if (ret == -EAGAIN) 24153fd0a558SYan, Zheng rc->commit_transaction = 1; 24163fd0a558SYan, Zheng return ret; 24173fd0a558SYan, Zheng } 24183fd0a558SYan, Zheng 24193fd0a558SYan, Zheng return 0; 24203fd0a558SYan, Zheng } 24213fd0a558SYan, Zheng 24223fd0a558SYan, Zheng static void release_metadata_space(struct reloc_control *rc, 24233fd0a558SYan, Zheng struct backref_node *node) 24243fd0a558SYan, Zheng { 24253fd0a558SYan, Zheng u64 num_bytes = calcu_metadata_size(rc, node, 0) * 2; 24263fd0a558SYan, Zheng btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, num_bytes); 24275d4f98a2SYan Zheng } 24285d4f98a2SYan Zheng 24295d4f98a2SYan Zheng /* 24305d4f98a2SYan Zheng * relocate a block tree, and then update pointers in upper level 24315d4f98a2SYan Zheng * blocks that reference the block to point to the new location. 24325d4f98a2SYan Zheng * 24335d4f98a2SYan Zheng * if called by link_to_upper, the block has already been relocated. 24345d4f98a2SYan Zheng * in that case this function just updates pointers. 24355d4f98a2SYan Zheng */ 24365d4f98a2SYan Zheng static int do_relocation(struct btrfs_trans_handle *trans, 24373fd0a558SYan, Zheng struct reloc_control *rc, 24385d4f98a2SYan Zheng struct backref_node *node, 24395d4f98a2SYan Zheng struct btrfs_key *key, 24405d4f98a2SYan Zheng struct btrfs_path *path, int lowest) 24415d4f98a2SYan Zheng { 24425d4f98a2SYan Zheng struct backref_node *upper; 24435d4f98a2SYan Zheng struct backref_edge *edge; 24445d4f98a2SYan Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 24455d4f98a2SYan Zheng struct btrfs_root *root; 24465d4f98a2SYan Zheng struct extent_buffer *eb; 24475d4f98a2SYan Zheng u32 blocksize; 24485d4f98a2SYan Zheng u64 bytenr; 24495d4f98a2SYan Zheng u64 generation; 24505d4f98a2SYan Zheng int nr; 24515d4f98a2SYan Zheng int slot; 24525d4f98a2SYan Zheng int ret; 24535d4f98a2SYan Zheng int err = 0; 24545d4f98a2SYan Zheng 24555d4f98a2SYan Zheng BUG_ON(lowest && node->eb); 24565d4f98a2SYan Zheng 24575d4f98a2SYan Zheng path->lowest_level = node->level + 1; 24583fd0a558SYan, Zheng rc->backref_cache.path[node->level] = node; 24595d4f98a2SYan Zheng list_for_each_entry(edge, &node->upper, list[LOWER]) { 24605d4f98a2SYan Zheng cond_resched(); 24615d4f98a2SYan Zheng 24625d4f98a2SYan Zheng upper = edge->node[UPPER]; 24633fd0a558SYan, Zheng root = select_reloc_root(trans, rc, upper, edges, &nr); 24643fd0a558SYan, Zheng BUG_ON(!root); 24655d4f98a2SYan Zheng 24663fd0a558SYan, Zheng if (upper->eb && !upper->locked) { 24673fd0a558SYan, Zheng if (!lowest) { 24683fd0a558SYan, Zheng ret = btrfs_bin_search(upper->eb, key, 24693fd0a558SYan, Zheng upper->level, &slot); 24703fd0a558SYan, Zheng BUG_ON(ret); 24713fd0a558SYan, Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 24723fd0a558SYan, Zheng if (node->eb->start == bytenr) 24733fd0a558SYan, Zheng goto next; 24743fd0a558SYan, Zheng } 24755d4f98a2SYan Zheng drop_node_buffer(upper); 24763fd0a558SYan, Zheng } 24775d4f98a2SYan Zheng 24785d4f98a2SYan Zheng if (!upper->eb) { 24795d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 24805d4f98a2SYan Zheng if (ret < 0) { 24815d4f98a2SYan Zheng err = ret; 24825d4f98a2SYan Zheng break; 24835d4f98a2SYan Zheng } 24845d4f98a2SYan Zheng BUG_ON(ret > 0); 24855d4f98a2SYan Zheng 24863fd0a558SYan, Zheng if (!upper->eb) { 24873fd0a558SYan, Zheng upper->eb = path->nodes[upper->level]; 24883fd0a558SYan, Zheng path->nodes[upper->level] = NULL; 24893fd0a558SYan, Zheng } else { 24903fd0a558SYan, Zheng BUG_ON(upper->eb != path->nodes[upper->level]); 24913fd0a558SYan, Zheng } 24923fd0a558SYan, Zheng 24933fd0a558SYan, Zheng upper->locked = 1; 24943fd0a558SYan, Zheng path->locks[upper->level] = 0; 24953fd0a558SYan, Zheng 24965d4f98a2SYan Zheng slot = path->slots[upper->level]; 24975d4f98a2SYan Zheng btrfs_release_path(NULL, path); 24985d4f98a2SYan Zheng } else { 24995d4f98a2SYan Zheng ret = btrfs_bin_search(upper->eb, key, upper->level, 25005d4f98a2SYan Zheng &slot); 25015d4f98a2SYan Zheng BUG_ON(ret); 25025d4f98a2SYan Zheng } 25035d4f98a2SYan Zheng 25045d4f98a2SYan Zheng bytenr = btrfs_node_blockptr(upper->eb, slot); 25053fd0a558SYan, Zheng if (lowest) { 25063fd0a558SYan, Zheng BUG_ON(bytenr != node->bytenr); 25075d4f98a2SYan Zheng } else { 25083fd0a558SYan, Zheng if (node->eb->start == bytenr) 25093fd0a558SYan, Zheng goto next; 25105d4f98a2SYan Zheng } 25115d4f98a2SYan Zheng 25125d4f98a2SYan Zheng blocksize = btrfs_level_size(root, node->level); 25135d4f98a2SYan Zheng generation = btrfs_node_ptr_generation(upper->eb, slot); 25145d4f98a2SYan Zheng eb = read_tree_block(root, bytenr, blocksize, generation); 25155d4f98a2SYan Zheng btrfs_tree_lock(eb); 25165d4f98a2SYan Zheng btrfs_set_lock_blocking(eb); 25175d4f98a2SYan Zheng 25185d4f98a2SYan Zheng if (!node->eb) { 25195d4f98a2SYan Zheng ret = btrfs_cow_block(trans, root, eb, upper->eb, 25205d4f98a2SYan Zheng slot, &eb); 25213fd0a558SYan, Zheng btrfs_tree_unlock(eb); 25223fd0a558SYan, Zheng free_extent_buffer(eb); 25235d4f98a2SYan Zheng if (ret < 0) { 25245d4f98a2SYan Zheng err = ret; 25253fd0a558SYan, Zheng goto next; 25265d4f98a2SYan Zheng } 25273fd0a558SYan, Zheng BUG_ON(node->eb != eb); 25285d4f98a2SYan Zheng } else { 25295d4f98a2SYan Zheng btrfs_set_node_blockptr(upper->eb, slot, 25305d4f98a2SYan Zheng node->eb->start); 25315d4f98a2SYan Zheng btrfs_set_node_ptr_generation(upper->eb, slot, 25325d4f98a2SYan Zheng trans->transid); 25335d4f98a2SYan Zheng btrfs_mark_buffer_dirty(upper->eb); 25345d4f98a2SYan Zheng 25355d4f98a2SYan Zheng ret = btrfs_inc_extent_ref(trans, root, 25365d4f98a2SYan Zheng node->eb->start, blocksize, 25375d4f98a2SYan Zheng upper->eb->start, 25385d4f98a2SYan Zheng btrfs_header_owner(upper->eb), 25395d4f98a2SYan Zheng node->level, 0); 25405d4f98a2SYan Zheng BUG_ON(ret); 25415d4f98a2SYan Zheng 25425d4f98a2SYan Zheng ret = btrfs_drop_subtree(trans, root, eb, upper->eb); 25435d4f98a2SYan Zheng BUG_ON(ret); 25445d4f98a2SYan Zheng } 25453fd0a558SYan, Zheng next: 25463fd0a558SYan, Zheng if (!upper->pending) 25473fd0a558SYan, Zheng drop_node_buffer(upper); 25483fd0a558SYan, Zheng else 25493fd0a558SYan, Zheng unlock_node_buffer(upper); 25503fd0a558SYan, Zheng if (err) 25513fd0a558SYan, Zheng break; 25525d4f98a2SYan Zheng } 25533fd0a558SYan, Zheng 25543fd0a558SYan, Zheng if (!err && node->pending) { 25553fd0a558SYan, Zheng drop_node_buffer(node); 25563fd0a558SYan, Zheng list_move_tail(&node->list, &rc->backref_cache.changed); 25573fd0a558SYan, Zheng node->pending = 0; 25585d4f98a2SYan Zheng } 25593fd0a558SYan, Zheng 25605d4f98a2SYan Zheng path->lowest_level = 0; 25613fd0a558SYan, Zheng BUG_ON(err == -ENOSPC); 25625d4f98a2SYan Zheng return err; 25635d4f98a2SYan Zheng } 25645d4f98a2SYan Zheng 25655d4f98a2SYan Zheng static int link_to_upper(struct btrfs_trans_handle *trans, 25663fd0a558SYan, Zheng struct reloc_control *rc, 25675d4f98a2SYan Zheng struct backref_node *node, 25685d4f98a2SYan Zheng struct btrfs_path *path) 25695d4f98a2SYan Zheng { 25705d4f98a2SYan Zheng struct btrfs_key key; 25715d4f98a2SYan Zheng 25725d4f98a2SYan Zheng btrfs_node_key_to_cpu(node->eb, &key, 0); 25733fd0a558SYan, Zheng return do_relocation(trans, rc, node, &key, path, 0); 25745d4f98a2SYan Zheng } 25755d4f98a2SYan Zheng 25765d4f98a2SYan Zheng static int finish_pending_nodes(struct btrfs_trans_handle *trans, 25773fd0a558SYan, Zheng struct reloc_control *rc, 25783fd0a558SYan, Zheng struct btrfs_path *path, int err) 25795d4f98a2SYan Zheng { 25803fd0a558SYan, Zheng LIST_HEAD(list); 25813fd0a558SYan, Zheng struct backref_cache *cache = &rc->backref_cache; 25825d4f98a2SYan Zheng struct backref_node *node; 25835d4f98a2SYan Zheng int level; 25845d4f98a2SYan Zheng int ret; 25855d4f98a2SYan Zheng 25865d4f98a2SYan Zheng for (level = 0; level < BTRFS_MAX_LEVEL; level++) { 25875d4f98a2SYan Zheng while (!list_empty(&cache->pending[level])) { 25885d4f98a2SYan Zheng node = list_entry(cache->pending[level].next, 25893fd0a558SYan, Zheng struct backref_node, list); 25903fd0a558SYan, Zheng list_move_tail(&node->list, &list); 25913fd0a558SYan, Zheng BUG_ON(!node->pending); 25925d4f98a2SYan Zheng 25933fd0a558SYan, Zheng if (!err) { 25943fd0a558SYan, Zheng ret = link_to_upper(trans, rc, node, path); 25955d4f98a2SYan Zheng if (ret < 0) 25965d4f98a2SYan Zheng err = ret; 25975d4f98a2SYan Zheng } 25985d4f98a2SYan Zheng } 25993fd0a558SYan, Zheng list_splice_init(&list, &cache->pending[level]); 26003fd0a558SYan, Zheng } 26015d4f98a2SYan Zheng return err; 26025d4f98a2SYan Zheng } 26035d4f98a2SYan Zheng 26045d4f98a2SYan Zheng static void mark_block_processed(struct reloc_control *rc, 26053fd0a558SYan, Zheng u64 bytenr, u32 blocksize) 26063fd0a558SYan, Zheng { 26073fd0a558SYan, Zheng set_extent_bits(&rc->processed_blocks, bytenr, bytenr + blocksize - 1, 26083fd0a558SYan, Zheng EXTENT_DIRTY, GFP_NOFS); 26093fd0a558SYan, Zheng } 26103fd0a558SYan, Zheng 26113fd0a558SYan, Zheng static void __mark_block_processed(struct reloc_control *rc, 26125d4f98a2SYan Zheng struct backref_node *node) 26135d4f98a2SYan Zheng { 26145d4f98a2SYan Zheng u32 blocksize; 26155d4f98a2SYan Zheng if (node->level == 0 || 26165d4f98a2SYan Zheng in_block_group(node->bytenr, rc->block_group)) { 26175d4f98a2SYan Zheng blocksize = btrfs_level_size(rc->extent_root, node->level); 26183fd0a558SYan, Zheng mark_block_processed(rc, node->bytenr, blocksize); 26195d4f98a2SYan Zheng } 26205d4f98a2SYan Zheng node->processed = 1; 26215d4f98a2SYan Zheng } 26225d4f98a2SYan Zheng 26235d4f98a2SYan Zheng /* 26245d4f98a2SYan Zheng * mark a block and all blocks directly/indirectly reference the block 26255d4f98a2SYan Zheng * as processed. 26265d4f98a2SYan Zheng */ 26275d4f98a2SYan Zheng static void update_processed_blocks(struct reloc_control *rc, 26285d4f98a2SYan Zheng struct backref_node *node) 26295d4f98a2SYan Zheng { 26305d4f98a2SYan Zheng struct backref_node *next = node; 26315d4f98a2SYan Zheng struct backref_edge *edge; 26325d4f98a2SYan Zheng struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; 26335d4f98a2SYan Zheng int index = 0; 26345d4f98a2SYan Zheng 26355d4f98a2SYan Zheng while (next) { 26365d4f98a2SYan Zheng cond_resched(); 26375d4f98a2SYan Zheng while (1) { 26385d4f98a2SYan Zheng if (next->processed) 26395d4f98a2SYan Zheng break; 26405d4f98a2SYan Zheng 26413fd0a558SYan, Zheng __mark_block_processed(rc, next); 26425d4f98a2SYan Zheng 26435d4f98a2SYan Zheng if (list_empty(&next->upper)) 26445d4f98a2SYan Zheng break; 26455d4f98a2SYan Zheng 26465d4f98a2SYan Zheng edge = list_entry(next->upper.next, 26475d4f98a2SYan Zheng struct backref_edge, list[LOWER]); 26485d4f98a2SYan Zheng edges[index++] = edge; 26495d4f98a2SYan Zheng next = edge->node[UPPER]; 26505d4f98a2SYan Zheng } 26515d4f98a2SYan Zheng next = walk_down_backref(edges, &index); 26525d4f98a2SYan Zheng } 26535d4f98a2SYan Zheng } 26545d4f98a2SYan Zheng 26555d4f98a2SYan Zheng static int tree_block_processed(u64 bytenr, u32 blocksize, 26565d4f98a2SYan Zheng struct reloc_control *rc) 26575d4f98a2SYan Zheng { 26585d4f98a2SYan Zheng if (test_range_bit(&rc->processed_blocks, bytenr, 26599655d298SChris Mason bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) 26605d4f98a2SYan Zheng return 1; 26615d4f98a2SYan Zheng return 0; 26625d4f98a2SYan Zheng } 26635d4f98a2SYan Zheng 26645d4f98a2SYan Zheng static int get_tree_block_key(struct reloc_control *rc, 26655d4f98a2SYan Zheng struct tree_block *block) 26665d4f98a2SYan Zheng { 26675d4f98a2SYan Zheng struct extent_buffer *eb; 26685d4f98a2SYan Zheng 26695d4f98a2SYan Zheng BUG_ON(block->key_ready); 26705d4f98a2SYan Zheng eb = read_tree_block(rc->extent_root, block->bytenr, 26715d4f98a2SYan Zheng block->key.objectid, block->key.offset); 26725d4f98a2SYan Zheng WARN_ON(btrfs_header_level(eb) != block->level); 26735d4f98a2SYan Zheng if (block->level == 0) 26745d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &block->key, 0); 26755d4f98a2SYan Zheng else 26765d4f98a2SYan Zheng btrfs_node_key_to_cpu(eb, &block->key, 0); 26775d4f98a2SYan Zheng free_extent_buffer(eb); 26785d4f98a2SYan Zheng block->key_ready = 1; 26795d4f98a2SYan Zheng return 0; 26805d4f98a2SYan Zheng } 26815d4f98a2SYan Zheng 26825d4f98a2SYan Zheng static int reada_tree_block(struct reloc_control *rc, 26835d4f98a2SYan Zheng struct tree_block *block) 26845d4f98a2SYan Zheng { 26855d4f98a2SYan Zheng BUG_ON(block->key_ready); 26865d4f98a2SYan Zheng readahead_tree_block(rc->extent_root, block->bytenr, 26875d4f98a2SYan Zheng block->key.objectid, block->key.offset); 26885d4f98a2SYan Zheng return 0; 26895d4f98a2SYan Zheng } 26905d4f98a2SYan Zheng 26915d4f98a2SYan Zheng /* 26925d4f98a2SYan Zheng * helper function to relocate a tree block 26935d4f98a2SYan Zheng */ 26945d4f98a2SYan Zheng static int relocate_tree_block(struct btrfs_trans_handle *trans, 26955d4f98a2SYan Zheng struct reloc_control *rc, 26965d4f98a2SYan Zheng struct backref_node *node, 26975d4f98a2SYan Zheng struct btrfs_key *key, 26985d4f98a2SYan Zheng struct btrfs_path *path) 26995d4f98a2SYan Zheng { 27005d4f98a2SYan Zheng struct btrfs_root *root; 27013fd0a558SYan, Zheng int release = 0; 27023fd0a558SYan, Zheng int ret = 0; 27035d4f98a2SYan Zheng 27043fd0a558SYan, Zheng if (!node) 27055d4f98a2SYan Zheng return 0; 27063fd0a558SYan, Zheng 27073fd0a558SYan, Zheng BUG_ON(node->processed); 27083fd0a558SYan, Zheng root = select_one_root(trans, node); 27093fd0a558SYan, Zheng if (root == ERR_PTR(-ENOENT)) { 27103fd0a558SYan, Zheng update_processed_blocks(rc, node); 27113fd0a558SYan, Zheng goto out; 27125d4f98a2SYan Zheng } 27135d4f98a2SYan Zheng 27143fd0a558SYan, Zheng if (!root || root->ref_cows) { 27153fd0a558SYan, Zheng ret = reserve_metadata_space(trans, rc, node); 27163fd0a558SYan, Zheng if (ret) 27175d4f98a2SYan Zheng goto out; 27183fd0a558SYan, Zheng release = 1; 27195d4f98a2SYan Zheng } 27203fd0a558SYan, Zheng 27213fd0a558SYan, Zheng if (root) { 27223fd0a558SYan, Zheng if (root->ref_cows) { 27233fd0a558SYan, Zheng BUG_ON(node->new_bytenr); 27243fd0a558SYan, Zheng BUG_ON(!list_empty(&node->list)); 27253fd0a558SYan, Zheng btrfs_record_root_in_trans(trans, root); 27263fd0a558SYan, Zheng root = root->reloc_root; 27273fd0a558SYan, Zheng node->new_bytenr = root->node->start; 27283fd0a558SYan, Zheng node->root = root; 27293fd0a558SYan, Zheng list_add_tail(&node->list, &rc->backref_cache.changed); 27303fd0a558SYan, Zheng } else { 27315d4f98a2SYan Zheng path->lowest_level = node->level; 27325d4f98a2SYan Zheng ret = btrfs_search_slot(trans, root, key, path, 0, 1); 27335d4f98a2SYan Zheng btrfs_release_path(root, path); 27343fd0a558SYan, Zheng if (ret > 0) 27355d4f98a2SYan Zheng ret = 0; 27363fd0a558SYan, Zheng } 27373fd0a558SYan, Zheng if (!ret) 27383fd0a558SYan, Zheng update_processed_blocks(rc, node); 27393fd0a558SYan, Zheng } else { 27403fd0a558SYan, Zheng ret = do_relocation(trans, rc, node, key, path, 1); 27413fd0a558SYan, Zheng } 27425d4f98a2SYan Zheng out: 27433fd0a558SYan, Zheng if (ret || node->level == 0 || node->cowonly) { 27443fd0a558SYan, Zheng if (release) 27453fd0a558SYan, Zheng release_metadata_space(rc, node); 27463fd0a558SYan, Zheng remove_backref_node(&rc->backref_cache, node); 27473fd0a558SYan, Zheng } 27485d4f98a2SYan Zheng return ret; 27495d4f98a2SYan Zheng } 27505d4f98a2SYan Zheng 27515d4f98a2SYan Zheng /* 27525d4f98a2SYan Zheng * relocate a list of blocks 27535d4f98a2SYan Zheng */ 27545d4f98a2SYan Zheng static noinline_for_stack 27555d4f98a2SYan Zheng int relocate_tree_blocks(struct btrfs_trans_handle *trans, 27565d4f98a2SYan Zheng struct reloc_control *rc, struct rb_root *blocks) 27575d4f98a2SYan Zheng { 27585d4f98a2SYan Zheng struct backref_node *node; 27595d4f98a2SYan Zheng struct btrfs_path *path; 27605d4f98a2SYan Zheng struct tree_block *block; 27615d4f98a2SYan Zheng struct rb_node *rb_node; 27625d4f98a2SYan Zheng int ret; 27635d4f98a2SYan Zheng int err = 0; 27645d4f98a2SYan Zheng 27655d4f98a2SYan Zheng path = btrfs_alloc_path(); 27665d4f98a2SYan Zheng if (!path) 27675d4f98a2SYan Zheng return -ENOMEM; 27685d4f98a2SYan Zheng 27695d4f98a2SYan Zheng rb_node = rb_first(blocks); 27705d4f98a2SYan Zheng while (rb_node) { 27715d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 27725d4f98a2SYan Zheng if (!block->key_ready) 27735d4f98a2SYan Zheng reada_tree_block(rc, block); 27745d4f98a2SYan Zheng rb_node = rb_next(rb_node); 27755d4f98a2SYan Zheng } 27765d4f98a2SYan Zheng 27775d4f98a2SYan Zheng rb_node = rb_first(blocks); 27785d4f98a2SYan Zheng while (rb_node) { 27795d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 27805d4f98a2SYan Zheng if (!block->key_ready) 27815d4f98a2SYan Zheng get_tree_block_key(rc, block); 27825d4f98a2SYan Zheng rb_node = rb_next(rb_node); 27835d4f98a2SYan Zheng } 27845d4f98a2SYan Zheng 27855d4f98a2SYan Zheng rb_node = rb_first(blocks); 27865d4f98a2SYan Zheng while (rb_node) { 27875d4f98a2SYan Zheng block = rb_entry(rb_node, struct tree_block, rb_node); 27885d4f98a2SYan Zheng 27893fd0a558SYan, Zheng node = build_backref_tree(rc, &block->key, 27905d4f98a2SYan Zheng block->level, block->bytenr); 27915d4f98a2SYan Zheng if (IS_ERR(node)) { 27925d4f98a2SYan Zheng err = PTR_ERR(node); 27935d4f98a2SYan Zheng goto out; 27945d4f98a2SYan Zheng } 27955d4f98a2SYan Zheng 27965d4f98a2SYan Zheng ret = relocate_tree_block(trans, rc, node, &block->key, 27975d4f98a2SYan Zheng path); 27985d4f98a2SYan Zheng if (ret < 0) { 27993fd0a558SYan, Zheng if (ret != -EAGAIN || rb_node == rb_first(blocks)) 28005d4f98a2SYan Zheng err = ret; 28015d4f98a2SYan Zheng goto out; 28025d4f98a2SYan Zheng } 28035d4f98a2SYan Zheng rb_node = rb_next(rb_node); 28045d4f98a2SYan Zheng } 28055d4f98a2SYan Zheng out: 28065d4f98a2SYan Zheng free_block_list(blocks); 28073fd0a558SYan, Zheng err = finish_pending_nodes(trans, rc, path, err); 28085d4f98a2SYan Zheng 28095d4f98a2SYan Zheng btrfs_free_path(path); 28105d4f98a2SYan Zheng return err; 28115d4f98a2SYan Zheng } 28125d4f98a2SYan Zheng 28135d4f98a2SYan Zheng static noinline_for_stack 2814efa56464SYan, Zheng int prealloc_file_extent_cluster(struct inode *inode, 2815efa56464SYan, Zheng struct file_extent_cluster *cluster) 2816efa56464SYan, Zheng { 2817efa56464SYan, Zheng u64 alloc_hint = 0; 2818efa56464SYan, Zheng u64 start; 2819efa56464SYan, Zheng u64 end; 2820efa56464SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 2821efa56464SYan, Zheng u64 num_bytes; 2822efa56464SYan, Zheng int nr = 0; 2823efa56464SYan, Zheng int ret = 0; 2824efa56464SYan, Zheng 2825efa56464SYan, Zheng BUG_ON(cluster->start != cluster->boundary[0]); 2826efa56464SYan, Zheng mutex_lock(&inode->i_mutex); 2827efa56464SYan, Zheng 2828efa56464SYan, Zheng ret = btrfs_check_data_free_space(inode, cluster->end + 2829efa56464SYan, Zheng 1 - cluster->start); 2830efa56464SYan, Zheng if (ret) 2831efa56464SYan, Zheng goto out; 2832efa56464SYan, Zheng 2833efa56464SYan, Zheng while (nr < cluster->nr) { 2834efa56464SYan, Zheng start = cluster->boundary[nr] - offset; 2835efa56464SYan, Zheng if (nr + 1 < cluster->nr) 2836efa56464SYan, Zheng end = cluster->boundary[nr + 1] - 1 - offset; 2837efa56464SYan, Zheng else 2838efa56464SYan, Zheng end = cluster->end - offset; 2839efa56464SYan, Zheng 2840efa56464SYan, Zheng lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); 2841efa56464SYan, Zheng num_bytes = end + 1 - start; 2842efa56464SYan, Zheng ret = btrfs_prealloc_file_range(inode, 0, start, 2843efa56464SYan, Zheng num_bytes, num_bytes, 2844efa56464SYan, Zheng end + 1, &alloc_hint); 2845efa56464SYan, Zheng unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); 2846efa56464SYan, Zheng if (ret) 2847efa56464SYan, Zheng break; 2848efa56464SYan, Zheng nr++; 2849efa56464SYan, Zheng } 2850efa56464SYan, Zheng btrfs_free_reserved_data_space(inode, cluster->end + 2851efa56464SYan, Zheng 1 - cluster->start); 2852efa56464SYan, Zheng out: 2853efa56464SYan, Zheng mutex_unlock(&inode->i_mutex); 2854efa56464SYan, Zheng return ret; 2855efa56464SYan, Zheng } 2856efa56464SYan, Zheng 2857efa56464SYan, Zheng static noinline_for_stack 28580257bb82SYan, Zheng int setup_extent_mapping(struct inode *inode, u64 start, u64 end, 28590257bb82SYan, Zheng u64 block_start) 28605d4f98a2SYan Zheng { 28615d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(inode)->root; 28625d4f98a2SYan Zheng struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; 28635d4f98a2SYan Zheng struct extent_map *em; 28640257bb82SYan, Zheng int ret = 0; 28655d4f98a2SYan Zheng 28665d4f98a2SYan Zheng em = alloc_extent_map(GFP_NOFS); 28670257bb82SYan, Zheng if (!em) 28680257bb82SYan, Zheng return -ENOMEM; 28690257bb82SYan, Zheng 28705d4f98a2SYan Zheng em->start = start; 28710257bb82SYan, Zheng em->len = end + 1 - start; 28720257bb82SYan, Zheng em->block_len = em->len; 28730257bb82SYan, Zheng em->block_start = block_start; 28745d4f98a2SYan Zheng em->bdev = root->fs_info->fs_devices->latest_bdev; 28755d4f98a2SYan Zheng set_bit(EXTENT_FLAG_PINNED, &em->flags); 28765d4f98a2SYan Zheng 28775d4f98a2SYan Zheng lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); 28785d4f98a2SYan Zheng while (1) { 2879890871beSChris Mason write_lock(&em_tree->lock); 28805d4f98a2SYan Zheng ret = add_extent_mapping(em_tree, em); 2881890871beSChris Mason write_unlock(&em_tree->lock); 28825d4f98a2SYan Zheng if (ret != -EEXIST) { 28835d4f98a2SYan Zheng free_extent_map(em); 28845d4f98a2SYan Zheng break; 28855d4f98a2SYan Zheng } 28865d4f98a2SYan Zheng btrfs_drop_extent_cache(inode, start, end, 0); 28875d4f98a2SYan Zheng } 28885d4f98a2SYan Zheng unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); 28890257bb82SYan, Zheng return ret; 28900257bb82SYan, Zheng } 28915d4f98a2SYan Zheng 28920257bb82SYan, Zheng static int relocate_file_extent_cluster(struct inode *inode, 28930257bb82SYan, Zheng struct file_extent_cluster *cluster) 28940257bb82SYan, Zheng { 28950257bb82SYan, Zheng u64 page_start; 28960257bb82SYan, Zheng u64 page_end; 28970257bb82SYan, Zheng u64 offset = BTRFS_I(inode)->index_cnt; 28980257bb82SYan, Zheng unsigned long index; 28990257bb82SYan, Zheng unsigned long last_index; 29000257bb82SYan, Zheng struct page *page; 29010257bb82SYan, Zheng struct file_ra_state *ra; 29020257bb82SYan, Zheng int nr = 0; 29030257bb82SYan, Zheng int ret = 0; 29040257bb82SYan, Zheng 29050257bb82SYan, Zheng if (!cluster->nr) 29060257bb82SYan, Zheng return 0; 29070257bb82SYan, Zheng 29080257bb82SYan, Zheng ra = kzalloc(sizeof(*ra), GFP_NOFS); 29090257bb82SYan, Zheng if (!ra) 29100257bb82SYan, Zheng return -ENOMEM; 29110257bb82SYan, Zheng 2912efa56464SYan, Zheng ret = prealloc_file_extent_cluster(inode, cluster); 29130257bb82SYan, Zheng if (ret) 2914efa56464SYan, Zheng goto out; 29150257bb82SYan, Zheng 29160257bb82SYan, Zheng file_ra_state_init(ra, inode->i_mapping); 29170257bb82SYan, Zheng 2918efa56464SYan, Zheng ret = setup_extent_mapping(inode, cluster->start - offset, 2919efa56464SYan, Zheng cluster->end - offset, cluster->start); 2920efa56464SYan, Zheng if (ret) 2921efa56464SYan, Zheng goto out; 2922efa56464SYan, Zheng 2923efa56464SYan, Zheng index = (cluster->start - offset) >> PAGE_CACHE_SHIFT; 2924efa56464SYan, Zheng last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT; 29250257bb82SYan, Zheng while (index <= last_index) { 2926efa56464SYan, Zheng ret = btrfs_delalloc_reserve_metadata(inode, PAGE_CACHE_SIZE); 2927efa56464SYan, Zheng if (ret) 2928efa56464SYan, Zheng goto out; 2929efa56464SYan, Zheng 29300257bb82SYan, Zheng page = find_lock_page(inode->i_mapping, index); 29310257bb82SYan, Zheng if (!page) { 29320257bb82SYan, Zheng page_cache_sync_readahead(inode->i_mapping, 29330257bb82SYan, Zheng ra, NULL, index, 29340257bb82SYan, Zheng last_index + 1 - index); 29350257bb82SYan, Zheng page = grab_cache_page(inode->i_mapping, index); 29360257bb82SYan, Zheng if (!page) { 2937efa56464SYan, Zheng btrfs_delalloc_release_metadata(inode, 2938efa56464SYan, Zheng PAGE_CACHE_SIZE); 29390257bb82SYan, Zheng ret = -ENOMEM; 2940efa56464SYan, Zheng goto out; 29410257bb82SYan, Zheng } 29420257bb82SYan, Zheng } 29430257bb82SYan, Zheng 29440257bb82SYan, Zheng if (PageReadahead(page)) { 29450257bb82SYan, Zheng page_cache_async_readahead(inode->i_mapping, 29460257bb82SYan, Zheng ra, NULL, page, index, 29470257bb82SYan, Zheng last_index + 1 - index); 29480257bb82SYan, Zheng } 29490257bb82SYan, Zheng 29500257bb82SYan, Zheng if (!PageUptodate(page)) { 29510257bb82SYan, Zheng btrfs_readpage(NULL, page); 29520257bb82SYan, Zheng lock_page(page); 29530257bb82SYan, Zheng if (!PageUptodate(page)) { 29540257bb82SYan, Zheng unlock_page(page); 29550257bb82SYan, Zheng page_cache_release(page); 2956efa56464SYan, Zheng btrfs_delalloc_release_metadata(inode, 2957efa56464SYan, Zheng PAGE_CACHE_SIZE); 29580257bb82SYan, Zheng ret = -EIO; 2959efa56464SYan, Zheng goto out; 29600257bb82SYan, Zheng } 29610257bb82SYan, Zheng } 29620257bb82SYan, Zheng 29630257bb82SYan, Zheng page_start = (u64)page->index << PAGE_CACHE_SHIFT; 29640257bb82SYan, Zheng page_end = page_start + PAGE_CACHE_SIZE - 1; 29650257bb82SYan, Zheng 29660257bb82SYan, Zheng lock_extent(&BTRFS_I(inode)->io_tree, 29670257bb82SYan, Zheng page_start, page_end, GFP_NOFS); 29680257bb82SYan, Zheng 29690257bb82SYan, Zheng set_page_extent_mapped(page); 29700257bb82SYan, Zheng 29710257bb82SYan, Zheng if (nr < cluster->nr && 29720257bb82SYan, Zheng page_start + offset == cluster->boundary[nr]) { 29730257bb82SYan, Zheng set_extent_bits(&BTRFS_I(inode)->io_tree, 29740257bb82SYan, Zheng page_start, page_end, 29750257bb82SYan, Zheng EXTENT_BOUNDARY, GFP_NOFS); 29760257bb82SYan, Zheng nr++; 29770257bb82SYan, Zheng } 29780257bb82SYan, Zheng 2979efa56464SYan, Zheng btrfs_set_extent_delalloc(inode, page_start, page_end, NULL); 29800257bb82SYan, Zheng set_page_dirty(page); 29810257bb82SYan, Zheng 29820257bb82SYan, Zheng unlock_extent(&BTRFS_I(inode)->io_tree, 29830257bb82SYan, Zheng page_start, page_end, GFP_NOFS); 29840257bb82SYan, Zheng unlock_page(page); 29850257bb82SYan, Zheng page_cache_release(page); 29860257bb82SYan, Zheng 29870257bb82SYan, Zheng index++; 2988efa56464SYan, Zheng balance_dirty_pages_ratelimited(inode->i_mapping); 2989efa56464SYan, Zheng btrfs_throttle(BTRFS_I(inode)->root); 29900257bb82SYan, Zheng } 29910257bb82SYan, Zheng WARN_ON(nr != cluster->nr); 2992efa56464SYan, Zheng out: 29930257bb82SYan, Zheng kfree(ra); 29940257bb82SYan, Zheng return ret; 29950257bb82SYan, Zheng } 29960257bb82SYan, Zheng 29970257bb82SYan, Zheng static noinline_for_stack 29980257bb82SYan, Zheng int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, 29990257bb82SYan, Zheng struct file_extent_cluster *cluster) 30000257bb82SYan, Zheng { 30010257bb82SYan, Zheng int ret; 30020257bb82SYan, Zheng 30030257bb82SYan, Zheng if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) { 30040257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 30050257bb82SYan, Zheng if (ret) 30060257bb82SYan, Zheng return ret; 30070257bb82SYan, Zheng cluster->nr = 0; 30080257bb82SYan, Zheng } 30090257bb82SYan, Zheng 30100257bb82SYan, Zheng if (!cluster->nr) 30110257bb82SYan, Zheng cluster->start = extent_key->objectid; 30120257bb82SYan, Zheng else 30130257bb82SYan, Zheng BUG_ON(cluster->nr >= MAX_EXTENTS); 30140257bb82SYan, Zheng cluster->end = extent_key->objectid + extent_key->offset - 1; 30150257bb82SYan, Zheng cluster->boundary[cluster->nr] = extent_key->objectid; 30160257bb82SYan, Zheng cluster->nr++; 30170257bb82SYan, Zheng 30180257bb82SYan, Zheng if (cluster->nr >= MAX_EXTENTS) { 30190257bb82SYan, Zheng ret = relocate_file_extent_cluster(inode, cluster); 30200257bb82SYan, Zheng if (ret) 30210257bb82SYan, Zheng return ret; 30220257bb82SYan, Zheng cluster->nr = 0; 30230257bb82SYan, Zheng } 30240257bb82SYan, Zheng return 0; 30255d4f98a2SYan Zheng } 30265d4f98a2SYan Zheng 30275d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 30285d4f98a2SYan Zheng static int get_ref_objectid_v0(struct reloc_control *rc, 30295d4f98a2SYan Zheng struct btrfs_path *path, 30305d4f98a2SYan Zheng struct btrfs_key *extent_key, 30315d4f98a2SYan Zheng u64 *ref_objectid, int *path_change) 30325d4f98a2SYan Zheng { 30335d4f98a2SYan Zheng struct btrfs_key key; 30345d4f98a2SYan Zheng struct extent_buffer *leaf; 30355d4f98a2SYan Zheng struct btrfs_extent_ref_v0 *ref0; 30365d4f98a2SYan Zheng int ret; 30375d4f98a2SYan Zheng int slot; 30385d4f98a2SYan Zheng 30395d4f98a2SYan Zheng leaf = path->nodes[0]; 30405d4f98a2SYan Zheng slot = path->slots[0]; 30415d4f98a2SYan Zheng while (1) { 30425d4f98a2SYan Zheng if (slot >= btrfs_header_nritems(leaf)) { 30435d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 30445d4f98a2SYan Zheng if (ret < 0) 30455d4f98a2SYan Zheng return ret; 30465d4f98a2SYan Zheng BUG_ON(ret > 0); 30475d4f98a2SYan Zheng leaf = path->nodes[0]; 30485d4f98a2SYan Zheng slot = path->slots[0]; 30495d4f98a2SYan Zheng if (path_change) 30505d4f98a2SYan Zheng *path_change = 1; 30515d4f98a2SYan Zheng } 30525d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, slot); 30535d4f98a2SYan Zheng if (key.objectid != extent_key->objectid) 30545d4f98a2SYan Zheng return -ENOENT; 30555d4f98a2SYan Zheng 30565d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_REF_V0_KEY) { 30575d4f98a2SYan Zheng slot++; 30585d4f98a2SYan Zheng continue; 30595d4f98a2SYan Zheng } 30605d4f98a2SYan Zheng ref0 = btrfs_item_ptr(leaf, slot, 30615d4f98a2SYan Zheng struct btrfs_extent_ref_v0); 30625d4f98a2SYan Zheng *ref_objectid = btrfs_ref_objectid_v0(leaf, ref0); 30635d4f98a2SYan Zheng break; 30645d4f98a2SYan Zheng } 30655d4f98a2SYan Zheng return 0; 30665d4f98a2SYan Zheng } 30675d4f98a2SYan Zheng #endif 30685d4f98a2SYan Zheng 30695d4f98a2SYan Zheng /* 30705d4f98a2SYan Zheng * helper to add a tree block to the list. 30715d4f98a2SYan Zheng * the major work is getting the generation and level of the block 30725d4f98a2SYan Zheng */ 30735d4f98a2SYan Zheng static int add_tree_block(struct reloc_control *rc, 30745d4f98a2SYan Zheng struct btrfs_key *extent_key, 30755d4f98a2SYan Zheng struct btrfs_path *path, 30765d4f98a2SYan Zheng struct rb_root *blocks) 30775d4f98a2SYan Zheng { 30785d4f98a2SYan Zheng struct extent_buffer *eb; 30795d4f98a2SYan Zheng struct btrfs_extent_item *ei; 30805d4f98a2SYan Zheng struct btrfs_tree_block_info *bi; 30815d4f98a2SYan Zheng struct tree_block *block; 30825d4f98a2SYan Zheng struct rb_node *rb_node; 30835d4f98a2SYan Zheng u32 item_size; 30845d4f98a2SYan Zheng int level = -1; 30855d4f98a2SYan Zheng int generation; 30865d4f98a2SYan Zheng 30875d4f98a2SYan Zheng eb = path->nodes[0]; 30885d4f98a2SYan Zheng item_size = btrfs_item_size_nr(eb, path->slots[0]); 30895d4f98a2SYan Zheng 30905d4f98a2SYan Zheng if (item_size >= sizeof(*ei) + sizeof(*bi)) { 30915d4f98a2SYan Zheng ei = btrfs_item_ptr(eb, path->slots[0], 30925d4f98a2SYan Zheng struct btrfs_extent_item); 30935d4f98a2SYan Zheng bi = (struct btrfs_tree_block_info *)(ei + 1); 30945d4f98a2SYan Zheng generation = btrfs_extent_generation(eb, ei); 30955d4f98a2SYan Zheng level = btrfs_tree_block_level(eb, bi); 30965d4f98a2SYan Zheng } else { 30975d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 30985d4f98a2SYan Zheng u64 ref_owner; 30995d4f98a2SYan Zheng int ret; 31005d4f98a2SYan Zheng 31015d4f98a2SYan Zheng BUG_ON(item_size != sizeof(struct btrfs_extent_item_v0)); 31025d4f98a2SYan Zheng ret = get_ref_objectid_v0(rc, path, extent_key, 31035d4f98a2SYan Zheng &ref_owner, NULL); 3104411fc6bcSAndi Kleen if (ret < 0) 3105411fc6bcSAndi Kleen return ret; 31065d4f98a2SYan Zheng BUG_ON(ref_owner >= BTRFS_MAX_LEVEL); 31075d4f98a2SYan Zheng level = (int)ref_owner; 31085d4f98a2SYan Zheng /* FIXME: get real generation */ 31095d4f98a2SYan Zheng generation = 0; 31105d4f98a2SYan Zheng #else 31115d4f98a2SYan Zheng BUG(); 31125d4f98a2SYan Zheng #endif 31135d4f98a2SYan Zheng } 31145d4f98a2SYan Zheng 31155d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path); 31165d4f98a2SYan Zheng 31175d4f98a2SYan Zheng BUG_ON(level == -1); 31185d4f98a2SYan Zheng 31195d4f98a2SYan Zheng block = kmalloc(sizeof(*block), GFP_NOFS); 31205d4f98a2SYan Zheng if (!block) 31215d4f98a2SYan Zheng return -ENOMEM; 31225d4f98a2SYan Zheng 31235d4f98a2SYan Zheng block->bytenr = extent_key->objectid; 31245d4f98a2SYan Zheng block->key.objectid = extent_key->offset; 31255d4f98a2SYan Zheng block->key.offset = generation; 31265d4f98a2SYan Zheng block->level = level; 31275d4f98a2SYan Zheng block->key_ready = 0; 31285d4f98a2SYan Zheng 31295d4f98a2SYan Zheng rb_node = tree_insert(blocks, block->bytenr, &block->rb_node); 31305d4f98a2SYan Zheng BUG_ON(rb_node); 31315d4f98a2SYan Zheng 31325d4f98a2SYan Zheng return 0; 31335d4f98a2SYan Zheng } 31345d4f98a2SYan Zheng 31355d4f98a2SYan Zheng /* 31365d4f98a2SYan Zheng * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY 31375d4f98a2SYan Zheng */ 31385d4f98a2SYan Zheng static int __add_tree_block(struct reloc_control *rc, 31395d4f98a2SYan Zheng u64 bytenr, u32 blocksize, 31405d4f98a2SYan Zheng struct rb_root *blocks) 31415d4f98a2SYan Zheng { 31425d4f98a2SYan Zheng struct btrfs_path *path; 31435d4f98a2SYan Zheng struct btrfs_key key; 31445d4f98a2SYan Zheng int ret; 31455d4f98a2SYan Zheng 31465d4f98a2SYan Zheng if (tree_block_processed(bytenr, blocksize, rc)) 31475d4f98a2SYan Zheng return 0; 31485d4f98a2SYan Zheng 31495d4f98a2SYan Zheng if (tree_search(blocks, bytenr)) 31505d4f98a2SYan Zheng return 0; 31515d4f98a2SYan Zheng 31525d4f98a2SYan Zheng path = btrfs_alloc_path(); 31535d4f98a2SYan Zheng if (!path) 31545d4f98a2SYan Zheng return -ENOMEM; 31555d4f98a2SYan Zheng 31565d4f98a2SYan Zheng key.objectid = bytenr; 31575d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 31585d4f98a2SYan Zheng key.offset = blocksize; 31595d4f98a2SYan Zheng 31605d4f98a2SYan Zheng path->search_commit_root = 1; 31615d4f98a2SYan Zheng path->skip_locking = 1; 31625d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); 31635d4f98a2SYan Zheng if (ret < 0) 31645d4f98a2SYan Zheng goto out; 31655d4f98a2SYan Zheng BUG_ON(ret); 31665d4f98a2SYan Zheng 31675d4f98a2SYan Zheng btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); 31685d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, blocks); 31695d4f98a2SYan Zheng out: 31705d4f98a2SYan Zheng btrfs_free_path(path); 31715d4f98a2SYan Zheng return ret; 31725d4f98a2SYan Zheng } 31735d4f98a2SYan Zheng 31745d4f98a2SYan Zheng /* 31755d4f98a2SYan Zheng * helper to check if the block use full backrefs for pointers in it 31765d4f98a2SYan Zheng */ 31775d4f98a2SYan Zheng static int block_use_full_backref(struct reloc_control *rc, 31785d4f98a2SYan Zheng struct extent_buffer *eb) 31795d4f98a2SYan Zheng { 31805d4f98a2SYan Zheng u64 flags; 31815d4f98a2SYan Zheng int ret; 31825d4f98a2SYan Zheng 31835d4f98a2SYan Zheng if (btrfs_header_flag(eb, BTRFS_HEADER_FLAG_RELOC) || 31845d4f98a2SYan Zheng btrfs_header_backref_rev(eb) < BTRFS_MIXED_BACKREF_REV) 31855d4f98a2SYan Zheng return 1; 31865d4f98a2SYan Zheng 31873fd0a558SYan, Zheng ret = btrfs_lookup_extent_info(NULL, rc->extent_root, 31883fd0a558SYan, Zheng eb->start, eb->len, NULL, &flags); 31895d4f98a2SYan Zheng BUG_ON(ret); 31905d4f98a2SYan Zheng 31915d4f98a2SYan Zheng if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) 31925d4f98a2SYan Zheng ret = 1; 31935d4f98a2SYan Zheng else 31945d4f98a2SYan Zheng ret = 0; 31955d4f98a2SYan Zheng return ret; 31965d4f98a2SYan Zheng } 31975d4f98a2SYan Zheng 31980af3d00bSJosef Bacik static int delete_block_group_cache(struct btrfs_fs_info *fs_info, 31990af3d00bSJosef Bacik struct inode *inode, u64 ino) 32000af3d00bSJosef Bacik { 32010af3d00bSJosef Bacik struct btrfs_key key; 32020af3d00bSJosef Bacik struct btrfs_path *path; 32030af3d00bSJosef Bacik struct btrfs_root *root = fs_info->tree_root; 32040af3d00bSJosef Bacik struct btrfs_trans_handle *trans; 32050af3d00bSJosef Bacik unsigned long nr; 32060af3d00bSJosef Bacik int ret = 0; 32070af3d00bSJosef Bacik 32080af3d00bSJosef Bacik if (inode) 32090af3d00bSJosef Bacik goto truncate; 32100af3d00bSJosef Bacik 32110af3d00bSJosef Bacik key.objectid = ino; 32120af3d00bSJosef Bacik key.type = BTRFS_INODE_ITEM_KEY; 32130af3d00bSJosef Bacik key.offset = 0; 32140af3d00bSJosef Bacik 32150af3d00bSJosef Bacik inode = btrfs_iget(fs_info->sb, &key, root, NULL); 32160af3d00bSJosef Bacik if (!inode || IS_ERR(inode) || is_bad_inode(inode)) { 32170af3d00bSJosef Bacik if (inode && !IS_ERR(inode)) 32180af3d00bSJosef Bacik iput(inode); 32190af3d00bSJosef Bacik return -ENOENT; 32200af3d00bSJosef Bacik } 32210af3d00bSJosef Bacik 32220af3d00bSJosef Bacik truncate: 32230af3d00bSJosef Bacik path = btrfs_alloc_path(); 32240af3d00bSJosef Bacik if (!path) { 32250af3d00bSJosef Bacik ret = -ENOMEM; 32260af3d00bSJosef Bacik goto out; 32270af3d00bSJosef Bacik } 32280af3d00bSJosef Bacik 32290af3d00bSJosef Bacik trans = btrfs_join_transaction(root, 0); 32300af3d00bSJosef Bacik if (IS_ERR(trans)) { 32310af3d00bSJosef Bacik btrfs_free_path(path); 32323612b495STsutomu Itoh ret = PTR_ERR(trans); 32330af3d00bSJosef Bacik goto out; 32340af3d00bSJosef Bacik } 32350af3d00bSJosef Bacik 32360af3d00bSJosef Bacik ret = btrfs_truncate_free_space_cache(root, trans, path, inode); 32370af3d00bSJosef Bacik 32380af3d00bSJosef Bacik btrfs_free_path(path); 32390af3d00bSJosef Bacik nr = trans->blocks_used; 32400af3d00bSJosef Bacik btrfs_end_transaction(trans, root); 32410af3d00bSJosef Bacik btrfs_btree_balance_dirty(root, nr); 32420af3d00bSJosef Bacik out: 32430af3d00bSJosef Bacik iput(inode); 32440af3d00bSJosef Bacik return ret; 32450af3d00bSJosef Bacik } 32460af3d00bSJosef Bacik 32475d4f98a2SYan Zheng /* 32485d4f98a2SYan Zheng * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY 32495d4f98a2SYan Zheng * this function scans fs tree to find blocks reference the data extent 32505d4f98a2SYan Zheng */ 32515d4f98a2SYan Zheng static int find_data_references(struct reloc_control *rc, 32525d4f98a2SYan Zheng struct btrfs_key *extent_key, 32535d4f98a2SYan Zheng struct extent_buffer *leaf, 32545d4f98a2SYan Zheng struct btrfs_extent_data_ref *ref, 32555d4f98a2SYan Zheng struct rb_root *blocks) 32565d4f98a2SYan Zheng { 32575d4f98a2SYan Zheng struct btrfs_path *path; 32585d4f98a2SYan Zheng struct tree_block *block; 32595d4f98a2SYan Zheng struct btrfs_root *root; 32605d4f98a2SYan Zheng struct btrfs_file_extent_item *fi; 32615d4f98a2SYan Zheng struct rb_node *rb_node; 32625d4f98a2SYan Zheng struct btrfs_key key; 32635d4f98a2SYan Zheng u64 ref_root; 32645d4f98a2SYan Zheng u64 ref_objectid; 32655d4f98a2SYan Zheng u64 ref_offset; 32665d4f98a2SYan Zheng u32 ref_count; 32675d4f98a2SYan Zheng u32 nritems; 32685d4f98a2SYan Zheng int err = 0; 32695d4f98a2SYan Zheng int added = 0; 32705d4f98a2SYan Zheng int counted; 32715d4f98a2SYan Zheng int ret; 32725d4f98a2SYan Zheng 32735d4f98a2SYan Zheng ref_root = btrfs_extent_data_ref_root(leaf, ref); 32745d4f98a2SYan Zheng ref_objectid = btrfs_extent_data_ref_objectid(leaf, ref); 32755d4f98a2SYan Zheng ref_offset = btrfs_extent_data_ref_offset(leaf, ref); 32765d4f98a2SYan Zheng ref_count = btrfs_extent_data_ref_count(leaf, ref); 32775d4f98a2SYan Zheng 32780af3d00bSJosef Bacik /* 32790af3d00bSJosef Bacik * This is an extent belonging to the free space cache, lets just delete 32800af3d00bSJosef Bacik * it and redo the search. 32810af3d00bSJosef Bacik */ 32820af3d00bSJosef Bacik if (ref_root == BTRFS_ROOT_TREE_OBJECTID) { 32830af3d00bSJosef Bacik ret = delete_block_group_cache(rc->extent_root->fs_info, 32840af3d00bSJosef Bacik NULL, ref_objectid); 32850af3d00bSJosef Bacik if (ret != -ENOENT) 32860af3d00bSJosef Bacik return ret; 32870af3d00bSJosef Bacik ret = 0; 32880af3d00bSJosef Bacik } 32890af3d00bSJosef Bacik 32900af3d00bSJosef Bacik path = btrfs_alloc_path(); 32910af3d00bSJosef Bacik if (!path) 32920af3d00bSJosef Bacik return -ENOMEM; 32930af3d00bSJosef Bacik 32945d4f98a2SYan Zheng root = read_fs_root(rc->extent_root->fs_info, ref_root); 32955d4f98a2SYan Zheng if (IS_ERR(root)) { 32965d4f98a2SYan Zheng err = PTR_ERR(root); 32975d4f98a2SYan Zheng goto out; 32985d4f98a2SYan Zheng } 32995d4f98a2SYan Zheng 33005d4f98a2SYan Zheng key.objectid = ref_objectid; 33015d4f98a2SYan Zheng key.offset = ref_offset; 33025d4f98a2SYan Zheng key.type = BTRFS_EXTENT_DATA_KEY; 33035d4f98a2SYan Zheng 33045d4f98a2SYan Zheng path->search_commit_root = 1; 33055d4f98a2SYan Zheng path->skip_locking = 1; 33065d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 33075d4f98a2SYan Zheng if (ret < 0) { 33085d4f98a2SYan Zheng err = ret; 33095d4f98a2SYan Zheng goto out; 33105d4f98a2SYan Zheng } 33115d4f98a2SYan Zheng 33125d4f98a2SYan Zheng leaf = path->nodes[0]; 33135d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 33145d4f98a2SYan Zheng /* 33155d4f98a2SYan Zheng * the references in tree blocks that use full backrefs 33165d4f98a2SYan Zheng * are not counted in 33175d4f98a2SYan Zheng */ 33185d4f98a2SYan Zheng if (block_use_full_backref(rc, leaf)) 33195d4f98a2SYan Zheng counted = 0; 33205d4f98a2SYan Zheng else 33215d4f98a2SYan Zheng counted = 1; 33225d4f98a2SYan Zheng rb_node = tree_search(blocks, leaf->start); 33235d4f98a2SYan Zheng if (rb_node) { 33245d4f98a2SYan Zheng if (counted) 33255d4f98a2SYan Zheng added = 1; 33265d4f98a2SYan Zheng else 33275d4f98a2SYan Zheng path->slots[0] = nritems; 33285d4f98a2SYan Zheng } 33295d4f98a2SYan Zheng 33305d4f98a2SYan Zheng while (ref_count > 0) { 33315d4f98a2SYan Zheng while (path->slots[0] >= nritems) { 33325d4f98a2SYan Zheng ret = btrfs_next_leaf(root, path); 33335d4f98a2SYan Zheng if (ret < 0) { 33345d4f98a2SYan Zheng err = ret; 33355d4f98a2SYan Zheng goto out; 33365d4f98a2SYan Zheng } 33375d4f98a2SYan Zheng if (ret > 0) { 33385d4f98a2SYan Zheng WARN_ON(1); 33395d4f98a2SYan Zheng goto out; 33405d4f98a2SYan Zheng } 33415d4f98a2SYan Zheng 33425d4f98a2SYan Zheng leaf = path->nodes[0]; 33435d4f98a2SYan Zheng nritems = btrfs_header_nritems(leaf); 33445d4f98a2SYan Zheng added = 0; 33455d4f98a2SYan Zheng 33465d4f98a2SYan Zheng if (block_use_full_backref(rc, leaf)) 33475d4f98a2SYan Zheng counted = 0; 33485d4f98a2SYan Zheng else 33495d4f98a2SYan Zheng counted = 1; 33505d4f98a2SYan Zheng rb_node = tree_search(blocks, leaf->start); 33515d4f98a2SYan Zheng if (rb_node) { 33525d4f98a2SYan Zheng if (counted) 33535d4f98a2SYan Zheng added = 1; 33545d4f98a2SYan Zheng else 33555d4f98a2SYan Zheng path->slots[0] = nritems; 33565d4f98a2SYan Zheng } 33575d4f98a2SYan Zheng } 33585d4f98a2SYan Zheng 33595d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 33605d4f98a2SYan Zheng if (key.objectid != ref_objectid || 33615d4f98a2SYan Zheng key.type != BTRFS_EXTENT_DATA_KEY) { 33625d4f98a2SYan Zheng WARN_ON(1); 33635d4f98a2SYan Zheng break; 33645d4f98a2SYan Zheng } 33655d4f98a2SYan Zheng 33665d4f98a2SYan Zheng fi = btrfs_item_ptr(leaf, path->slots[0], 33675d4f98a2SYan Zheng struct btrfs_file_extent_item); 33685d4f98a2SYan Zheng 33695d4f98a2SYan Zheng if (btrfs_file_extent_type(leaf, fi) == 33705d4f98a2SYan Zheng BTRFS_FILE_EXTENT_INLINE) 33715d4f98a2SYan Zheng goto next; 33725d4f98a2SYan Zheng 33735d4f98a2SYan Zheng if (btrfs_file_extent_disk_bytenr(leaf, fi) != 33745d4f98a2SYan Zheng extent_key->objectid) 33755d4f98a2SYan Zheng goto next; 33765d4f98a2SYan Zheng 33775d4f98a2SYan Zheng key.offset -= btrfs_file_extent_offset(leaf, fi); 33785d4f98a2SYan Zheng if (key.offset != ref_offset) 33795d4f98a2SYan Zheng goto next; 33805d4f98a2SYan Zheng 33815d4f98a2SYan Zheng if (counted) 33825d4f98a2SYan Zheng ref_count--; 33835d4f98a2SYan Zheng if (added) 33845d4f98a2SYan Zheng goto next; 33855d4f98a2SYan Zheng 33865d4f98a2SYan Zheng if (!tree_block_processed(leaf->start, leaf->len, rc)) { 33875d4f98a2SYan Zheng block = kmalloc(sizeof(*block), GFP_NOFS); 33885d4f98a2SYan Zheng if (!block) { 33895d4f98a2SYan Zheng err = -ENOMEM; 33905d4f98a2SYan Zheng break; 33915d4f98a2SYan Zheng } 33925d4f98a2SYan Zheng block->bytenr = leaf->start; 33935d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &block->key, 0); 33945d4f98a2SYan Zheng block->level = 0; 33955d4f98a2SYan Zheng block->key_ready = 1; 33965d4f98a2SYan Zheng rb_node = tree_insert(blocks, block->bytenr, 33975d4f98a2SYan Zheng &block->rb_node); 33985d4f98a2SYan Zheng BUG_ON(rb_node); 33995d4f98a2SYan Zheng } 34005d4f98a2SYan Zheng if (counted) 34015d4f98a2SYan Zheng added = 1; 34025d4f98a2SYan Zheng else 34035d4f98a2SYan Zheng path->slots[0] = nritems; 34045d4f98a2SYan Zheng next: 34055d4f98a2SYan Zheng path->slots[0]++; 34065d4f98a2SYan Zheng 34075d4f98a2SYan Zheng } 34085d4f98a2SYan Zheng out: 34095d4f98a2SYan Zheng btrfs_free_path(path); 34105d4f98a2SYan Zheng return err; 34115d4f98a2SYan Zheng } 34125d4f98a2SYan Zheng 34135d4f98a2SYan Zheng /* 34145d4f98a2SYan Zheng * hepler to find all tree blocks that reference a given data extent 34155d4f98a2SYan Zheng */ 34165d4f98a2SYan Zheng static noinline_for_stack 34175d4f98a2SYan Zheng int add_data_references(struct reloc_control *rc, 34185d4f98a2SYan Zheng struct btrfs_key *extent_key, 34195d4f98a2SYan Zheng struct btrfs_path *path, 34205d4f98a2SYan Zheng struct rb_root *blocks) 34215d4f98a2SYan Zheng { 34225d4f98a2SYan Zheng struct btrfs_key key; 34235d4f98a2SYan Zheng struct extent_buffer *eb; 34245d4f98a2SYan Zheng struct btrfs_extent_data_ref *dref; 34255d4f98a2SYan Zheng struct btrfs_extent_inline_ref *iref; 34265d4f98a2SYan Zheng unsigned long ptr; 34275d4f98a2SYan Zheng unsigned long end; 34283fd0a558SYan, Zheng u32 blocksize = btrfs_level_size(rc->extent_root, 0); 34295d4f98a2SYan Zheng int ret; 34305d4f98a2SYan Zheng int err = 0; 34315d4f98a2SYan Zheng 34325d4f98a2SYan Zheng eb = path->nodes[0]; 34335d4f98a2SYan Zheng ptr = btrfs_item_ptr_offset(eb, path->slots[0]); 34345d4f98a2SYan Zheng end = ptr + btrfs_item_size_nr(eb, path->slots[0]); 34355d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 34365d4f98a2SYan Zheng if (ptr + sizeof(struct btrfs_extent_item_v0) == end) 34375d4f98a2SYan Zheng ptr = end; 34385d4f98a2SYan Zheng else 34395d4f98a2SYan Zheng #endif 34405d4f98a2SYan Zheng ptr += sizeof(struct btrfs_extent_item); 34415d4f98a2SYan Zheng 34425d4f98a2SYan Zheng while (ptr < end) { 34435d4f98a2SYan Zheng iref = (struct btrfs_extent_inline_ref *)ptr; 34445d4f98a2SYan Zheng key.type = btrfs_extent_inline_ref_type(eb, iref); 34455d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_DATA_REF_KEY) { 34465d4f98a2SYan Zheng key.offset = btrfs_extent_inline_ref_offset(eb, iref); 34475d4f98a2SYan Zheng ret = __add_tree_block(rc, key.offset, blocksize, 34485d4f98a2SYan Zheng blocks); 34495d4f98a2SYan Zheng } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { 34505d4f98a2SYan Zheng dref = (struct btrfs_extent_data_ref *)(&iref->offset); 34515d4f98a2SYan Zheng ret = find_data_references(rc, extent_key, 34525d4f98a2SYan Zheng eb, dref, blocks); 34535d4f98a2SYan Zheng } else { 34545d4f98a2SYan Zheng BUG(); 34555d4f98a2SYan Zheng } 34565d4f98a2SYan Zheng ptr += btrfs_extent_inline_ref_size(key.type); 34575d4f98a2SYan Zheng } 34585d4f98a2SYan Zheng WARN_ON(ptr > end); 34595d4f98a2SYan Zheng 34605d4f98a2SYan Zheng while (1) { 34615d4f98a2SYan Zheng cond_resched(); 34625d4f98a2SYan Zheng eb = path->nodes[0]; 34635d4f98a2SYan Zheng if (path->slots[0] >= btrfs_header_nritems(eb)) { 34645d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 34655d4f98a2SYan Zheng if (ret < 0) { 34665d4f98a2SYan Zheng err = ret; 34675d4f98a2SYan Zheng break; 34685d4f98a2SYan Zheng } 34695d4f98a2SYan Zheng if (ret > 0) 34705d4f98a2SYan Zheng break; 34715d4f98a2SYan Zheng eb = path->nodes[0]; 34725d4f98a2SYan Zheng } 34735d4f98a2SYan Zheng 34745d4f98a2SYan Zheng btrfs_item_key_to_cpu(eb, &key, path->slots[0]); 34755d4f98a2SYan Zheng if (key.objectid != extent_key->objectid) 34765d4f98a2SYan Zheng break; 34775d4f98a2SYan Zheng 34785d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 34795d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_DATA_REF_KEY || 34805d4f98a2SYan Zheng key.type == BTRFS_EXTENT_REF_V0_KEY) { 34815d4f98a2SYan Zheng #else 34825d4f98a2SYan Zheng BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); 34835d4f98a2SYan Zheng if (key.type == BTRFS_SHARED_DATA_REF_KEY) { 34845d4f98a2SYan Zheng #endif 34855d4f98a2SYan Zheng ret = __add_tree_block(rc, key.offset, blocksize, 34865d4f98a2SYan Zheng blocks); 34875d4f98a2SYan Zheng } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { 34885d4f98a2SYan Zheng dref = btrfs_item_ptr(eb, path->slots[0], 34895d4f98a2SYan Zheng struct btrfs_extent_data_ref); 34905d4f98a2SYan Zheng ret = find_data_references(rc, extent_key, 34915d4f98a2SYan Zheng eb, dref, blocks); 34925d4f98a2SYan Zheng } else { 34935d4f98a2SYan Zheng ret = 0; 34945d4f98a2SYan Zheng } 34955d4f98a2SYan Zheng if (ret) { 34965d4f98a2SYan Zheng err = ret; 34975d4f98a2SYan Zheng break; 34985d4f98a2SYan Zheng } 34995d4f98a2SYan Zheng path->slots[0]++; 35005d4f98a2SYan Zheng } 35015d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path); 35025d4f98a2SYan Zheng if (err) 35035d4f98a2SYan Zheng free_block_list(blocks); 35045d4f98a2SYan Zheng return err; 35055d4f98a2SYan Zheng } 35065d4f98a2SYan Zheng 35075d4f98a2SYan Zheng /* 35085d4f98a2SYan Zheng * hepler to find next unprocessed extent 35095d4f98a2SYan Zheng */ 35105d4f98a2SYan Zheng static noinline_for_stack 35115d4f98a2SYan Zheng int find_next_extent(struct btrfs_trans_handle *trans, 35123fd0a558SYan, Zheng struct reloc_control *rc, struct btrfs_path *path, 35133fd0a558SYan, Zheng struct btrfs_key *extent_key) 35145d4f98a2SYan Zheng { 35155d4f98a2SYan Zheng struct btrfs_key key; 35165d4f98a2SYan Zheng struct extent_buffer *leaf; 35175d4f98a2SYan Zheng u64 start, end, last; 35185d4f98a2SYan Zheng int ret; 35195d4f98a2SYan Zheng 35205d4f98a2SYan Zheng last = rc->block_group->key.objectid + rc->block_group->key.offset; 35215d4f98a2SYan Zheng while (1) { 35225d4f98a2SYan Zheng cond_resched(); 35235d4f98a2SYan Zheng if (rc->search_start >= last) { 35245d4f98a2SYan Zheng ret = 1; 35255d4f98a2SYan Zheng break; 35265d4f98a2SYan Zheng } 35275d4f98a2SYan Zheng 35285d4f98a2SYan Zheng key.objectid = rc->search_start; 35295d4f98a2SYan Zheng key.type = BTRFS_EXTENT_ITEM_KEY; 35305d4f98a2SYan Zheng key.offset = 0; 35315d4f98a2SYan Zheng 35325d4f98a2SYan Zheng path->search_commit_root = 1; 35335d4f98a2SYan Zheng path->skip_locking = 1; 35345d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 35355d4f98a2SYan Zheng 0, 0); 35365d4f98a2SYan Zheng if (ret < 0) 35375d4f98a2SYan Zheng break; 35385d4f98a2SYan Zheng next: 35395d4f98a2SYan Zheng leaf = path->nodes[0]; 35405d4f98a2SYan Zheng if (path->slots[0] >= btrfs_header_nritems(leaf)) { 35415d4f98a2SYan Zheng ret = btrfs_next_leaf(rc->extent_root, path); 35425d4f98a2SYan Zheng if (ret != 0) 35435d4f98a2SYan Zheng break; 35445d4f98a2SYan Zheng leaf = path->nodes[0]; 35455d4f98a2SYan Zheng } 35465d4f98a2SYan Zheng 35475d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 35485d4f98a2SYan Zheng if (key.objectid >= last) { 35495d4f98a2SYan Zheng ret = 1; 35505d4f98a2SYan Zheng break; 35515d4f98a2SYan Zheng } 35525d4f98a2SYan Zheng 35535d4f98a2SYan Zheng if (key.type != BTRFS_EXTENT_ITEM_KEY || 35545d4f98a2SYan Zheng key.objectid + key.offset <= rc->search_start) { 35555d4f98a2SYan Zheng path->slots[0]++; 35565d4f98a2SYan Zheng goto next; 35575d4f98a2SYan Zheng } 35585d4f98a2SYan Zheng 35595d4f98a2SYan Zheng ret = find_first_extent_bit(&rc->processed_blocks, 35605d4f98a2SYan Zheng key.objectid, &start, &end, 35615d4f98a2SYan Zheng EXTENT_DIRTY); 35625d4f98a2SYan Zheng 35635d4f98a2SYan Zheng if (ret == 0 && start <= key.objectid) { 35645d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path); 35655d4f98a2SYan Zheng rc->search_start = end + 1; 35665d4f98a2SYan Zheng } else { 35675d4f98a2SYan Zheng rc->search_start = key.objectid + key.offset; 35683fd0a558SYan, Zheng memcpy(extent_key, &key, sizeof(key)); 35695d4f98a2SYan Zheng return 0; 35705d4f98a2SYan Zheng } 35715d4f98a2SYan Zheng } 35725d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path); 35735d4f98a2SYan Zheng return ret; 35745d4f98a2SYan Zheng } 35755d4f98a2SYan Zheng 35765d4f98a2SYan Zheng static void set_reloc_control(struct reloc_control *rc) 35775d4f98a2SYan Zheng { 35785d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 35795d4f98a2SYan Zheng mutex_lock(&fs_info->trans_mutex); 35805d4f98a2SYan Zheng fs_info->reloc_ctl = rc; 35815d4f98a2SYan Zheng mutex_unlock(&fs_info->trans_mutex); 35825d4f98a2SYan Zheng } 35835d4f98a2SYan Zheng 35845d4f98a2SYan Zheng static void unset_reloc_control(struct reloc_control *rc) 35855d4f98a2SYan Zheng { 35865d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; 35875d4f98a2SYan Zheng mutex_lock(&fs_info->trans_mutex); 35885d4f98a2SYan Zheng fs_info->reloc_ctl = NULL; 35895d4f98a2SYan Zheng mutex_unlock(&fs_info->trans_mutex); 35905d4f98a2SYan Zheng } 35915d4f98a2SYan Zheng 35925d4f98a2SYan Zheng static int check_extent_flags(u64 flags) 35935d4f98a2SYan Zheng { 35945d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 35955d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 35965d4f98a2SYan Zheng return 1; 35975d4f98a2SYan Zheng if (!(flags & BTRFS_EXTENT_FLAG_DATA) && 35985d4f98a2SYan Zheng !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) 35995d4f98a2SYan Zheng return 1; 36005d4f98a2SYan Zheng if ((flags & BTRFS_EXTENT_FLAG_DATA) && 36015d4f98a2SYan Zheng (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) 36025d4f98a2SYan Zheng return 1; 36035d4f98a2SYan Zheng return 0; 36045d4f98a2SYan Zheng } 36055d4f98a2SYan Zheng 36063fd0a558SYan, Zheng static noinline_for_stack 36073fd0a558SYan, Zheng int prepare_to_relocate(struct reloc_control *rc) 36083fd0a558SYan, Zheng { 36093fd0a558SYan, Zheng struct btrfs_trans_handle *trans; 36103fd0a558SYan, Zheng int ret; 36113fd0a558SYan, Zheng 36123fd0a558SYan, Zheng rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root); 36133fd0a558SYan, Zheng if (!rc->block_rsv) 36143fd0a558SYan, Zheng return -ENOMEM; 36153fd0a558SYan, Zheng 36163fd0a558SYan, Zheng /* 36173fd0a558SYan, Zheng * reserve some space for creating reloc trees. 36183fd0a558SYan, Zheng * btrfs_init_reloc_root will use them when there 36193fd0a558SYan, Zheng * is no reservation in transaction handle. 36203fd0a558SYan, Zheng */ 36213fd0a558SYan, Zheng ret = btrfs_block_rsv_add(NULL, rc->extent_root, rc->block_rsv, 36228bb8ab2eSJosef Bacik rc->extent_root->nodesize * 256); 36233fd0a558SYan, Zheng if (ret) 36243fd0a558SYan, Zheng return ret; 36253fd0a558SYan, Zheng 36263fd0a558SYan, Zheng rc->block_rsv->refill_used = 1; 36273fd0a558SYan, Zheng btrfs_add_durable_block_rsv(rc->extent_root->fs_info, rc->block_rsv); 36283fd0a558SYan, Zheng 36293fd0a558SYan, Zheng memset(&rc->cluster, 0, sizeof(rc->cluster)); 36303fd0a558SYan, Zheng rc->search_start = rc->block_group->key.objectid; 36313fd0a558SYan, Zheng rc->extents_found = 0; 36323fd0a558SYan, Zheng rc->nodes_relocated = 0; 36333fd0a558SYan, Zheng rc->merging_rsv_size = 0; 36343fd0a558SYan, Zheng 36353fd0a558SYan, Zheng rc->create_reloc_tree = 1; 36363fd0a558SYan, Zheng set_reloc_control(rc); 36373fd0a558SYan, Zheng 36383fd0a558SYan, Zheng trans = btrfs_join_transaction(rc->extent_root, 1); 36393612b495STsutomu Itoh BUG_ON(IS_ERR(trans)); 36403fd0a558SYan, Zheng btrfs_commit_transaction(trans, rc->extent_root); 36413fd0a558SYan, Zheng return 0; 36423fd0a558SYan, Zheng } 364376dda93cSYan, Zheng 36445d4f98a2SYan Zheng static noinline_for_stack int relocate_block_group(struct reloc_control *rc) 36455d4f98a2SYan Zheng { 36465d4f98a2SYan Zheng struct rb_root blocks = RB_ROOT; 36475d4f98a2SYan Zheng struct btrfs_key key; 36485d4f98a2SYan Zheng struct btrfs_trans_handle *trans = NULL; 36495d4f98a2SYan Zheng struct btrfs_path *path; 36505d4f98a2SYan Zheng struct btrfs_extent_item *ei; 36515d4f98a2SYan Zheng unsigned long nr; 36525d4f98a2SYan Zheng u64 flags; 36535d4f98a2SYan Zheng u32 item_size; 36545d4f98a2SYan Zheng int ret; 36555d4f98a2SYan Zheng int err = 0; 36565d4f98a2SYan Zheng 36575d4f98a2SYan Zheng path = btrfs_alloc_path(); 36583fd0a558SYan, Zheng if (!path) 36595d4f98a2SYan Zheng return -ENOMEM; 36603fd0a558SYan, Zheng 36613fd0a558SYan, Zheng ret = prepare_to_relocate(rc); 36623fd0a558SYan, Zheng if (ret) { 36633fd0a558SYan, Zheng err = ret; 36643fd0a558SYan, Zheng goto out_free; 36652423fdfbSJiri Slaby } 36665d4f98a2SYan Zheng 36675d4f98a2SYan Zheng while (1) { 3668a22285a6SYan, Zheng trans = btrfs_start_transaction(rc->extent_root, 0); 366998d5dc13STsutomu Itoh BUG_ON(IS_ERR(trans)); 36705d4f98a2SYan Zheng 36713fd0a558SYan, Zheng if (update_backref_cache(trans, &rc->backref_cache)) { 36723fd0a558SYan, Zheng btrfs_end_transaction(trans, rc->extent_root); 36733fd0a558SYan, Zheng continue; 36743fd0a558SYan, Zheng } 36753fd0a558SYan, Zheng 36763fd0a558SYan, Zheng ret = find_next_extent(trans, rc, path, &key); 36775d4f98a2SYan Zheng if (ret < 0) 36785d4f98a2SYan Zheng err = ret; 36795d4f98a2SYan Zheng if (ret != 0) 36805d4f98a2SYan Zheng break; 36815d4f98a2SYan Zheng 36825d4f98a2SYan Zheng rc->extents_found++; 36835d4f98a2SYan Zheng 36845d4f98a2SYan Zheng ei = btrfs_item_ptr(path->nodes[0], path->slots[0], 36855d4f98a2SYan Zheng struct btrfs_extent_item); 36863fd0a558SYan, Zheng item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); 36875d4f98a2SYan Zheng if (item_size >= sizeof(*ei)) { 36885d4f98a2SYan Zheng flags = btrfs_extent_flags(path->nodes[0], ei); 36895d4f98a2SYan Zheng ret = check_extent_flags(flags); 36905d4f98a2SYan Zheng BUG_ON(ret); 36915d4f98a2SYan Zheng 36925d4f98a2SYan Zheng } else { 36935d4f98a2SYan Zheng #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 36945d4f98a2SYan Zheng u64 ref_owner; 36955d4f98a2SYan Zheng int path_change = 0; 36965d4f98a2SYan Zheng 36975d4f98a2SYan Zheng BUG_ON(item_size != 36985d4f98a2SYan Zheng sizeof(struct btrfs_extent_item_v0)); 36995d4f98a2SYan Zheng ret = get_ref_objectid_v0(rc, path, &key, &ref_owner, 37005d4f98a2SYan Zheng &path_change); 37015d4f98a2SYan Zheng if (ref_owner < BTRFS_FIRST_FREE_OBJECTID) 37025d4f98a2SYan Zheng flags = BTRFS_EXTENT_FLAG_TREE_BLOCK; 37035d4f98a2SYan Zheng else 37045d4f98a2SYan Zheng flags = BTRFS_EXTENT_FLAG_DATA; 37055d4f98a2SYan Zheng 37065d4f98a2SYan Zheng if (path_change) { 37075d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path); 37085d4f98a2SYan Zheng 37095d4f98a2SYan Zheng path->search_commit_root = 1; 37105d4f98a2SYan Zheng path->skip_locking = 1; 37115d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, rc->extent_root, 37125d4f98a2SYan Zheng &key, path, 0, 0); 37135d4f98a2SYan Zheng if (ret < 0) { 37145d4f98a2SYan Zheng err = ret; 37155d4f98a2SYan Zheng break; 37165d4f98a2SYan Zheng } 37175d4f98a2SYan Zheng BUG_ON(ret > 0); 37185d4f98a2SYan Zheng } 37195d4f98a2SYan Zheng #else 37205d4f98a2SYan Zheng BUG(); 37215d4f98a2SYan Zheng #endif 37225d4f98a2SYan Zheng } 37235d4f98a2SYan Zheng 37245d4f98a2SYan Zheng if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 37255d4f98a2SYan Zheng ret = add_tree_block(rc, &key, path, &blocks); 37265d4f98a2SYan Zheng } else if (rc->stage == UPDATE_DATA_PTRS && 37275d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 37285d4f98a2SYan Zheng ret = add_data_references(rc, &key, path, &blocks); 37295d4f98a2SYan Zheng } else { 37305d4f98a2SYan Zheng btrfs_release_path(rc->extent_root, path); 37315d4f98a2SYan Zheng ret = 0; 37325d4f98a2SYan Zheng } 37335d4f98a2SYan Zheng if (ret < 0) { 37343fd0a558SYan, Zheng err = ret; 37355d4f98a2SYan Zheng break; 37365d4f98a2SYan Zheng } 37375d4f98a2SYan Zheng 37385d4f98a2SYan Zheng if (!RB_EMPTY_ROOT(&blocks)) { 37395d4f98a2SYan Zheng ret = relocate_tree_blocks(trans, rc, &blocks); 37405d4f98a2SYan Zheng if (ret < 0) { 37413fd0a558SYan, Zheng if (ret != -EAGAIN) { 37425d4f98a2SYan Zheng err = ret; 37435d4f98a2SYan Zheng break; 37445d4f98a2SYan Zheng } 37453fd0a558SYan, Zheng rc->extents_found--; 37463fd0a558SYan, Zheng rc->search_start = key.objectid; 37473fd0a558SYan, Zheng } 37485d4f98a2SYan Zheng } 37495d4f98a2SYan Zheng 37503fd0a558SYan, Zheng ret = btrfs_block_rsv_check(trans, rc->extent_root, 37513fd0a558SYan, Zheng rc->block_rsv, 0, 5); 37523fd0a558SYan, Zheng if (ret < 0) { 37533fd0a558SYan, Zheng if (ret != -EAGAIN) { 37543fd0a558SYan, Zheng err = ret; 37553fd0a558SYan, Zheng WARN_ON(1); 37563fd0a558SYan, Zheng break; 37573fd0a558SYan, Zheng } 37583fd0a558SYan, Zheng rc->commit_transaction = 1; 37593fd0a558SYan, Zheng } 37603fd0a558SYan, Zheng 37613fd0a558SYan, Zheng if (rc->commit_transaction) { 37623fd0a558SYan, Zheng rc->commit_transaction = 0; 37633fd0a558SYan, Zheng ret = btrfs_commit_transaction(trans, rc->extent_root); 37643fd0a558SYan, Zheng BUG_ON(ret); 37653fd0a558SYan, Zheng } else { 37665d4f98a2SYan Zheng nr = trans->blocks_used; 37673fd0a558SYan, Zheng btrfs_end_transaction_throttle(trans, rc->extent_root); 37685d4f98a2SYan Zheng btrfs_btree_balance_dirty(rc->extent_root, nr); 37693fd0a558SYan, Zheng } 37703fd0a558SYan, Zheng trans = NULL; 37715d4f98a2SYan Zheng 37725d4f98a2SYan Zheng if (rc->stage == MOVE_DATA_EXTENTS && 37735d4f98a2SYan Zheng (flags & BTRFS_EXTENT_FLAG_DATA)) { 37745d4f98a2SYan Zheng rc->found_file_extent = 1; 37750257bb82SYan, Zheng ret = relocate_data_extent(rc->data_inode, 37763fd0a558SYan, Zheng &key, &rc->cluster); 37775d4f98a2SYan Zheng if (ret < 0) { 37785d4f98a2SYan Zheng err = ret; 37795d4f98a2SYan Zheng break; 37805d4f98a2SYan Zheng } 37815d4f98a2SYan Zheng } 37825d4f98a2SYan Zheng } 37833fd0a558SYan, Zheng 37843fd0a558SYan, Zheng btrfs_release_path(rc->extent_root, path); 37853fd0a558SYan, Zheng clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY, 37863fd0a558SYan, Zheng GFP_NOFS); 37875d4f98a2SYan Zheng 37885d4f98a2SYan Zheng if (trans) { 37895d4f98a2SYan Zheng nr = trans->blocks_used; 37903fd0a558SYan, Zheng btrfs_end_transaction_throttle(trans, rc->extent_root); 37915d4f98a2SYan Zheng btrfs_btree_balance_dirty(rc->extent_root, nr); 37925d4f98a2SYan Zheng } 37935d4f98a2SYan Zheng 37940257bb82SYan, Zheng if (!err) { 37953fd0a558SYan, Zheng ret = relocate_file_extent_cluster(rc->data_inode, 37963fd0a558SYan, Zheng &rc->cluster); 37970257bb82SYan, Zheng if (ret < 0) 37980257bb82SYan, Zheng err = ret; 37990257bb82SYan, Zheng } 38000257bb82SYan, Zheng 38013fd0a558SYan, Zheng rc->create_reloc_tree = 0; 38023fd0a558SYan, Zheng set_reloc_control(rc); 38030257bb82SYan, Zheng 38043fd0a558SYan, Zheng backref_cache_cleanup(&rc->backref_cache); 38053fd0a558SYan, Zheng btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1); 38065d4f98a2SYan Zheng 38073fd0a558SYan, Zheng err = prepare_to_merge(rc, err); 38085d4f98a2SYan Zheng 38095d4f98a2SYan Zheng merge_reloc_roots(rc); 38105d4f98a2SYan Zheng 38113fd0a558SYan, Zheng rc->merge_reloc_tree = 0; 38125d4f98a2SYan Zheng unset_reloc_control(rc); 38133fd0a558SYan, Zheng btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1); 38145d4f98a2SYan Zheng 38155d4f98a2SYan Zheng /* get rid of pinned extents */ 3816a22285a6SYan, Zheng trans = btrfs_join_transaction(rc->extent_root, 1); 38173612b495STsutomu Itoh if (IS_ERR(trans)) 38183612b495STsutomu Itoh err = PTR_ERR(trans); 38193612b495STsutomu Itoh else 38205d4f98a2SYan Zheng btrfs_commit_transaction(trans, rc->extent_root); 38213fd0a558SYan, Zheng out_free: 38223fd0a558SYan, Zheng btrfs_free_block_rsv(rc->extent_root, rc->block_rsv); 38233fd0a558SYan, Zheng btrfs_free_path(path); 38245d4f98a2SYan Zheng return err; 38255d4f98a2SYan Zheng } 38265d4f98a2SYan Zheng 38275d4f98a2SYan Zheng static int __insert_orphan_inode(struct btrfs_trans_handle *trans, 38280257bb82SYan, Zheng struct btrfs_root *root, u64 objectid) 38295d4f98a2SYan Zheng { 38305d4f98a2SYan Zheng struct btrfs_path *path; 38315d4f98a2SYan Zheng struct btrfs_inode_item *item; 38325d4f98a2SYan Zheng struct extent_buffer *leaf; 38335d4f98a2SYan Zheng int ret; 38345d4f98a2SYan Zheng 38355d4f98a2SYan Zheng path = btrfs_alloc_path(); 38365d4f98a2SYan Zheng if (!path) 38375d4f98a2SYan Zheng return -ENOMEM; 38385d4f98a2SYan Zheng 38395d4f98a2SYan Zheng ret = btrfs_insert_empty_inode(trans, root, path, objectid); 38405d4f98a2SYan Zheng if (ret) 38415d4f98a2SYan Zheng goto out; 38425d4f98a2SYan Zheng 38435d4f98a2SYan Zheng leaf = path->nodes[0]; 38445d4f98a2SYan Zheng item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); 38455d4f98a2SYan Zheng memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 38465d4f98a2SYan Zheng btrfs_set_inode_generation(leaf, item, 1); 38470257bb82SYan, Zheng btrfs_set_inode_size(leaf, item, 0); 38485d4f98a2SYan Zheng btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); 38493fd0a558SYan, Zheng btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS | 38503fd0a558SYan, Zheng BTRFS_INODE_PREALLOC); 38515d4f98a2SYan Zheng btrfs_mark_buffer_dirty(leaf); 38525d4f98a2SYan Zheng btrfs_release_path(root, path); 38535d4f98a2SYan Zheng out: 38545d4f98a2SYan Zheng btrfs_free_path(path); 38555d4f98a2SYan Zheng return ret; 38565d4f98a2SYan Zheng } 38575d4f98a2SYan Zheng 38585d4f98a2SYan Zheng /* 38595d4f98a2SYan Zheng * helper to create inode for data relocation. 38605d4f98a2SYan Zheng * the inode is in data relocation tree and its link count is 0 38615d4f98a2SYan Zheng */ 38623fd0a558SYan, Zheng static noinline_for_stack 38633fd0a558SYan, Zheng struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, 38645d4f98a2SYan Zheng struct btrfs_block_group_cache *group) 38655d4f98a2SYan Zheng { 38665d4f98a2SYan Zheng struct inode *inode = NULL; 38675d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 38685d4f98a2SYan Zheng struct btrfs_root *root; 38695d4f98a2SYan Zheng struct btrfs_key key; 38705d4f98a2SYan Zheng unsigned long nr; 38715d4f98a2SYan Zheng u64 objectid = BTRFS_FIRST_FREE_OBJECTID; 38725d4f98a2SYan Zheng int err = 0; 38735d4f98a2SYan Zheng 38745d4f98a2SYan Zheng root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); 38755d4f98a2SYan Zheng if (IS_ERR(root)) 38765d4f98a2SYan Zheng return ERR_CAST(root); 38775d4f98a2SYan Zheng 3878a22285a6SYan, Zheng trans = btrfs_start_transaction(root, 6); 38793fd0a558SYan, Zheng if (IS_ERR(trans)) 38803fd0a558SYan, Zheng return ERR_CAST(trans); 38815d4f98a2SYan Zheng 38825d4f98a2SYan Zheng err = btrfs_find_free_objectid(trans, root, objectid, &objectid); 38835d4f98a2SYan Zheng if (err) 38845d4f98a2SYan Zheng goto out; 38855d4f98a2SYan Zheng 38860257bb82SYan, Zheng err = __insert_orphan_inode(trans, root, objectid); 38875d4f98a2SYan Zheng BUG_ON(err); 38885d4f98a2SYan Zheng 38895d4f98a2SYan Zheng key.objectid = objectid; 38905d4f98a2SYan Zheng key.type = BTRFS_INODE_ITEM_KEY; 38915d4f98a2SYan Zheng key.offset = 0; 389273f73415SJosef Bacik inode = btrfs_iget(root->fs_info->sb, &key, root, NULL); 38935d4f98a2SYan Zheng BUG_ON(IS_ERR(inode) || is_bad_inode(inode)); 38945d4f98a2SYan Zheng BTRFS_I(inode)->index_cnt = group->key.objectid; 38955d4f98a2SYan Zheng 38965d4f98a2SYan Zheng err = btrfs_orphan_add(trans, inode); 38975d4f98a2SYan Zheng out: 38985d4f98a2SYan Zheng nr = trans->blocks_used; 38995d4f98a2SYan Zheng btrfs_end_transaction(trans, root); 39005d4f98a2SYan Zheng btrfs_btree_balance_dirty(root, nr); 39015d4f98a2SYan Zheng if (err) { 39025d4f98a2SYan Zheng if (inode) 39035d4f98a2SYan Zheng iput(inode); 39045d4f98a2SYan Zheng inode = ERR_PTR(err); 39055d4f98a2SYan Zheng } 39065d4f98a2SYan Zheng return inode; 39075d4f98a2SYan Zheng } 39085d4f98a2SYan Zheng 39093fd0a558SYan, Zheng static struct reloc_control *alloc_reloc_control(void) 39103fd0a558SYan, Zheng { 39113fd0a558SYan, Zheng struct reloc_control *rc; 39123fd0a558SYan, Zheng 39133fd0a558SYan, Zheng rc = kzalloc(sizeof(*rc), GFP_NOFS); 39143fd0a558SYan, Zheng if (!rc) 39153fd0a558SYan, Zheng return NULL; 39163fd0a558SYan, Zheng 39173fd0a558SYan, Zheng INIT_LIST_HEAD(&rc->reloc_roots); 39183fd0a558SYan, Zheng backref_cache_init(&rc->backref_cache); 39193fd0a558SYan, Zheng mapping_tree_init(&rc->reloc_root_tree); 39203fd0a558SYan, Zheng extent_io_tree_init(&rc->processed_blocks, NULL, GFP_NOFS); 39213fd0a558SYan, Zheng return rc; 39223fd0a558SYan, Zheng } 39233fd0a558SYan, Zheng 39245d4f98a2SYan Zheng /* 39255d4f98a2SYan Zheng * function to relocate all extents in a block group. 39265d4f98a2SYan Zheng */ 39275d4f98a2SYan Zheng int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) 39285d4f98a2SYan Zheng { 39295d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = extent_root->fs_info; 39305d4f98a2SYan Zheng struct reloc_control *rc; 39310af3d00bSJosef Bacik struct inode *inode; 39320af3d00bSJosef Bacik struct btrfs_path *path; 39335d4f98a2SYan Zheng int ret; 3934f0486c68SYan, Zheng int rw = 0; 39355d4f98a2SYan Zheng int err = 0; 39365d4f98a2SYan Zheng 39373fd0a558SYan, Zheng rc = alloc_reloc_control(); 39385d4f98a2SYan Zheng if (!rc) 39395d4f98a2SYan Zheng return -ENOMEM; 39405d4f98a2SYan Zheng 3941f0486c68SYan, Zheng rc->extent_root = extent_root; 39423fd0a558SYan, Zheng 39435d4f98a2SYan Zheng rc->block_group = btrfs_lookup_block_group(fs_info, group_start); 39445d4f98a2SYan Zheng BUG_ON(!rc->block_group); 39455d4f98a2SYan Zheng 3946f0486c68SYan, Zheng if (!rc->block_group->ro) { 3947f0486c68SYan, Zheng ret = btrfs_set_block_group_ro(extent_root, rc->block_group); 3948f0486c68SYan, Zheng if (ret) { 3949f0486c68SYan, Zheng err = ret; 3950f0486c68SYan, Zheng goto out; 3951f0486c68SYan, Zheng } 3952f0486c68SYan, Zheng rw = 1; 3953f0486c68SYan, Zheng } 3954f0486c68SYan, Zheng 39550af3d00bSJosef Bacik path = btrfs_alloc_path(); 39560af3d00bSJosef Bacik if (!path) { 39570af3d00bSJosef Bacik err = -ENOMEM; 39580af3d00bSJosef Bacik goto out; 39590af3d00bSJosef Bacik } 39600af3d00bSJosef Bacik 39610af3d00bSJosef Bacik inode = lookup_free_space_inode(fs_info->tree_root, rc->block_group, 39620af3d00bSJosef Bacik path); 39630af3d00bSJosef Bacik btrfs_free_path(path); 39640af3d00bSJosef Bacik 39650af3d00bSJosef Bacik if (!IS_ERR(inode)) 39660af3d00bSJosef Bacik ret = delete_block_group_cache(fs_info, inode, 0); 39670af3d00bSJosef Bacik else 39680af3d00bSJosef Bacik ret = PTR_ERR(inode); 39690af3d00bSJosef Bacik 39700af3d00bSJosef Bacik if (ret && ret != -ENOENT) { 39710af3d00bSJosef Bacik err = ret; 39720af3d00bSJosef Bacik goto out; 39730af3d00bSJosef Bacik } 39740af3d00bSJosef Bacik 39755d4f98a2SYan Zheng rc->data_inode = create_reloc_inode(fs_info, rc->block_group); 39765d4f98a2SYan Zheng if (IS_ERR(rc->data_inode)) { 39775d4f98a2SYan Zheng err = PTR_ERR(rc->data_inode); 39785d4f98a2SYan Zheng rc->data_inode = NULL; 39795d4f98a2SYan Zheng goto out; 39805d4f98a2SYan Zheng } 39815d4f98a2SYan Zheng 39825d4f98a2SYan Zheng printk(KERN_INFO "btrfs: relocating block group %llu flags %llu\n", 39835d4f98a2SYan Zheng (unsigned long long)rc->block_group->key.objectid, 39845d4f98a2SYan Zheng (unsigned long long)rc->block_group->flags); 39855d4f98a2SYan Zheng 398624bbcf04SYan, Zheng btrfs_start_delalloc_inodes(fs_info->tree_root, 0); 398724bbcf04SYan, Zheng btrfs_wait_ordered_extents(fs_info->tree_root, 0, 0); 39885d4f98a2SYan Zheng 39895d4f98a2SYan Zheng while (1) { 399076dda93cSYan, Zheng mutex_lock(&fs_info->cleaner_mutex); 399176dda93cSYan, Zheng 399276dda93cSYan, Zheng btrfs_clean_old_snapshots(fs_info->tree_root); 39935d4f98a2SYan Zheng ret = relocate_block_group(rc); 399476dda93cSYan, Zheng 399576dda93cSYan, Zheng mutex_unlock(&fs_info->cleaner_mutex); 39965d4f98a2SYan Zheng if (ret < 0) { 39975d4f98a2SYan Zheng err = ret; 39983fd0a558SYan, Zheng goto out; 39995d4f98a2SYan Zheng } 40005d4f98a2SYan Zheng 40015d4f98a2SYan Zheng if (rc->extents_found == 0) 40025d4f98a2SYan Zheng break; 40035d4f98a2SYan Zheng 40045d4f98a2SYan Zheng printk(KERN_INFO "btrfs: found %llu extents\n", 40055d4f98a2SYan Zheng (unsigned long long)rc->extents_found); 40065d4f98a2SYan Zheng 40075d4f98a2SYan Zheng if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { 40085d4f98a2SYan Zheng btrfs_wait_ordered_range(rc->data_inode, 0, (u64)-1); 40095d4f98a2SYan Zheng invalidate_mapping_pages(rc->data_inode->i_mapping, 40105d4f98a2SYan Zheng 0, -1); 40115d4f98a2SYan Zheng rc->stage = UPDATE_DATA_PTRS; 40125d4f98a2SYan Zheng } 40135d4f98a2SYan Zheng } 40145d4f98a2SYan Zheng 40150257bb82SYan, Zheng filemap_write_and_wait_range(fs_info->btree_inode->i_mapping, 40165d4f98a2SYan Zheng rc->block_group->key.objectid, 40175d4f98a2SYan Zheng rc->block_group->key.objectid + 40185d4f98a2SYan Zheng rc->block_group->key.offset - 1); 40195d4f98a2SYan Zheng 40205d4f98a2SYan Zheng WARN_ON(rc->block_group->pinned > 0); 40215d4f98a2SYan Zheng WARN_ON(rc->block_group->reserved > 0); 40225d4f98a2SYan Zheng WARN_ON(btrfs_block_group_used(&rc->block_group->item) > 0); 40235d4f98a2SYan Zheng out: 4024f0486c68SYan, Zheng if (err && rw) 4025f0486c68SYan, Zheng btrfs_set_block_group_rw(extent_root, rc->block_group); 40265d4f98a2SYan Zheng iput(rc->data_inode); 40275d4f98a2SYan Zheng btrfs_put_block_group(rc->block_group); 40285d4f98a2SYan Zheng kfree(rc); 40295d4f98a2SYan Zheng return err; 40305d4f98a2SYan Zheng } 40315d4f98a2SYan Zheng 403276dda93cSYan, Zheng static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) 403376dda93cSYan, Zheng { 403476dda93cSYan, Zheng struct btrfs_trans_handle *trans; 403576dda93cSYan, Zheng int ret; 403676dda93cSYan, Zheng 4037a22285a6SYan, Zheng trans = btrfs_start_transaction(root->fs_info->tree_root, 0); 403898d5dc13STsutomu Itoh BUG_ON(IS_ERR(trans)); 403976dda93cSYan, Zheng 404076dda93cSYan, Zheng memset(&root->root_item.drop_progress, 0, 404176dda93cSYan, Zheng sizeof(root->root_item.drop_progress)); 404276dda93cSYan, Zheng root->root_item.drop_level = 0; 404376dda93cSYan, Zheng btrfs_set_root_refs(&root->root_item, 0); 404476dda93cSYan, Zheng ret = btrfs_update_root(trans, root->fs_info->tree_root, 404576dda93cSYan, Zheng &root->root_key, &root->root_item); 404676dda93cSYan, Zheng BUG_ON(ret); 404776dda93cSYan, Zheng 404876dda93cSYan, Zheng ret = btrfs_end_transaction(trans, root->fs_info->tree_root); 404976dda93cSYan, Zheng BUG_ON(ret); 405076dda93cSYan, Zheng return 0; 405176dda93cSYan, Zheng } 405276dda93cSYan, Zheng 40535d4f98a2SYan Zheng /* 40545d4f98a2SYan Zheng * recover relocation interrupted by system crash. 40555d4f98a2SYan Zheng * 40565d4f98a2SYan Zheng * this function resumes merging reloc trees with corresponding fs trees. 40575d4f98a2SYan Zheng * this is important for keeping the sharing of tree blocks 40585d4f98a2SYan Zheng */ 40595d4f98a2SYan Zheng int btrfs_recover_relocation(struct btrfs_root *root) 40605d4f98a2SYan Zheng { 40615d4f98a2SYan Zheng LIST_HEAD(reloc_roots); 40625d4f98a2SYan Zheng struct btrfs_key key; 40635d4f98a2SYan Zheng struct btrfs_root *fs_root; 40645d4f98a2SYan Zheng struct btrfs_root *reloc_root; 40655d4f98a2SYan Zheng struct btrfs_path *path; 40665d4f98a2SYan Zheng struct extent_buffer *leaf; 40675d4f98a2SYan Zheng struct reloc_control *rc = NULL; 40685d4f98a2SYan Zheng struct btrfs_trans_handle *trans; 40695d4f98a2SYan Zheng int ret; 40705d4f98a2SYan Zheng int err = 0; 40715d4f98a2SYan Zheng 40725d4f98a2SYan Zheng path = btrfs_alloc_path(); 40735d4f98a2SYan Zheng if (!path) 40745d4f98a2SYan Zheng return -ENOMEM; 40755d4f98a2SYan Zheng 40765d4f98a2SYan Zheng key.objectid = BTRFS_TREE_RELOC_OBJECTID; 40775d4f98a2SYan Zheng key.type = BTRFS_ROOT_ITEM_KEY; 40785d4f98a2SYan Zheng key.offset = (u64)-1; 40795d4f98a2SYan Zheng 40805d4f98a2SYan Zheng while (1) { 40815d4f98a2SYan Zheng ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, 40825d4f98a2SYan Zheng path, 0, 0); 40835d4f98a2SYan Zheng if (ret < 0) { 40845d4f98a2SYan Zheng err = ret; 40855d4f98a2SYan Zheng goto out; 40865d4f98a2SYan Zheng } 40875d4f98a2SYan Zheng if (ret > 0) { 40885d4f98a2SYan Zheng if (path->slots[0] == 0) 40895d4f98a2SYan Zheng break; 40905d4f98a2SYan Zheng path->slots[0]--; 40915d4f98a2SYan Zheng } 40925d4f98a2SYan Zheng leaf = path->nodes[0]; 40935d4f98a2SYan Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 40945d4f98a2SYan Zheng btrfs_release_path(root->fs_info->tree_root, path); 40955d4f98a2SYan Zheng 40965d4f98a2SYan Zheng if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || 40975d4f98a2SYan Zheng key.type != BTRFS_ROOT_ITEM_KEY) 40985d4f98a2SYan Zheng break; 40995d4f98a2SYan Zheng 41005d4f98a2SYan Zheng reloc_root = btrfs_read_fs_root_no_radix(root, &key); 41015d4f98a2SYan Zheng if (IS_ERR(reloc_root)) { 41025d4f98a2SYan Zheng err = PTR_ERR(reloc_root); 41035d4f98a2SYan Zheng goto out; 41045d4f98a2SYan Zheng } 41055d4f98a2SYan Zheng 41065d4f98a2SYan Zheng list_add(&reloc_root->root_list, &reloc_roots); 41075d4f98a2SYan Zheng 41085d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) > 0) { 41095d4f98a2SYan Zheng fs_root = read_fs_root(root->fs_info, 41105d4f98a2SYan Zheng reloc_root->root_key.offset); 41115d4f98a2SYan Zheng if (IS_ERR(fs_root)) { 411276dda93cSYan, Zheng ret = PTR_ERR(fs_root); 411376dda93cSYan, Zheng if (ret != -ENOENT) { 411476dda93cSYan, Zheng err = ret; 41155d4f98a2SYan Zheng goto out; 41165d4f98a2SYan Zheng } 411776dda93cSYan, Zheng mark_garbage_root(reloc_root); 411876dda93cSYan, Zheng } 41195d4f98a2SYan Zheng } 41205d4f98a2SYan Zheng 41215d4f98a2SYan Zheng if (key.offset == 0) 41225d4f98a2SYan Zheng break; 41235d4f98a2SYan Zheng 41245d4f98a2SYan Zheng key.offset--; 41255d4f98a2SYan Zheng } 41265d4f98a2SYan Zheng btrfs_release_path(root->fs_info->tree_root, path); 41275d4f98a2SYan Zheng 41285d4f98a2SYan Zheng if (list_empty(&reloc_roots)) 41295d4f98a2SYan Zheng goto out; 41305d4f98a2SYan Zheng 41313fd0a558SYan, Zheng rc = alloc_reloc_control(); 41325d4f98a2SYan Zheng if (!rc) { 41335d4f98a2SYan Zheng err = -ENOMEM; 41345d4f98a2SYan Zheng goto out; 41355d4f98a2SYan Zheng } 41365d4f98a2SYan Zheng 41375d4f98a2SYan Zheng rc->extent_root = root->fs_info->extent_root; 41385d4f98a2SYan Zheng 41395d4f98a2SYan Zheng set_reloc_control(rc); 41405d4f98a2SYan Zheng 41413fd0a558SYan, Zheng trans = btrfs_join_transaction(rc->extent_root, 1); 41423612b495STsutomu Itoh if (IS_ERR(trans)) { 41433612b495STsutomu Itoh unset_reloc_control(rc); 41443612b495STsutomu Itoh err = PTR_ERR(trans); 41453612b495STsutomu Itoh goto out_free; 41463612b495STsutomu Itoh } 41473fd0a558SYan, Zheng 41483fd0a558SYan, Zheng rc->merge_reloc_tree = 1; 41493fd0a558SYan, Zheng 41505d4f98a2SYan Zheng while (!list_empty(&reloc_roots)) { 41515d4f98a2SYan Zheng reloc_root = list_entry(reloc_roots.next, 41525d4f98a2SYan Zheng struct btrfs_root, root_list); 41535d4f98a2SYan Zheng list_del(&reloc_root->root_list); 41545d4f98a2SYan Zheng 41555d4f98a2SYan Zheng if (btrfs_root_refs(&reloc_root->root_item) == 0) { 41565d4f98a2SYan Zheng list_add_tail(&reloc_root->root_list, 41575d4f98a2SYan Zheng &rc->reloc_roots); 41585d4f98a2SYan Zheng continue; 41595d4f98a2SYan Zheng } 41605d4f98a2SYan Zheng 41615d4f98a2SYan Zheng fs_root = read_fs_root(root->fs_info, 41625d4f98a2SYan Zheng reloc_root->root_key.offset); 41635d4f98a2SYan Zheng BUG_ON(IS_ERR(fs_root)); 41645d4f98a2SYan Zheng 41655d4f98a2SYan Zheng __add_reloc_root(reloc_root); 41665d4f98a2SYan Zheng fs_root->reloc_root = reloc_root; 41675d4f98a2SYan Zheng } 41685d4f98a2SYan Zheng 41695d4f98a2SYan Zheng btrfs_commit_transaction(trans, rc->extent_root); 41705d4f98a2SYan Zheng 41715d4f98a2SYan Zheng merge_reloc_roots(rc); 41725d4f98a2SYan Zheng 41735d4f98a2SYan Zheng unset_reloc_control(rc); 41745d4f98a2SYan Zheng 41753fd0a558SYan, Zheng trans = btrfs_join_transaction(rc->extent_root, 1); 41763612b495STsutomu Itoh if (IS_ERR(trans)) 41773612b495STsutomu Itoh err = PTR_ERR(trans); 41783612b495STsutomu Itoh else 41795d4f98a2SYan Zheng btrfs_commit_transaction(trans, rc->extent_root); 41803612b495STsutomu Itoh out_free: 41815d4f98a2SYan Zheng kfree(rc); 41823612b495STsutomu Itoh out: 41835d4f98a2SYan Zheng while (!list_empty(&reloc_roots)) { 41845d4f98a2SYan Zheng reloc_root = list_entry(reloc_roots.next, 41855d4f98a2SYan Zheng struct btrfs_root, root_list); 41865d4f98a2SYan Zheng list_del(&reloc_root->root_list); 41875d4f98a2SYan Zheng free_extent_buffer(reloc_root->node); 41885d4f98a2SYan Zheng free_extent_buffer(reloc_root->commit_root); 41895d4f98a2SYan Zheng kfree(reloc_root); 41905d4f98a2SYan Zheng } 41915d4f98a2SYan Zheng btrfs_free_path(path); 41925d4f98a2SYan Zheng 41935d4f98a2SYan Zheng if (err == 0) { 41945d4f98a2SYan Zheng /* cleanup orphan inode in data relocation tree */ 41955d4f98a2SYan Zheng fs_root = read_fs_root(root->fs_info, 41965d4f98a2SYan Zheng BTRFS_DATA_RELOC_TREE_OBJECTID); 41975d4f98a2SYan Zheng if (IS_ERR(fs_root)) 41985d4f98a2SYan Zheng err = PTR_ERR(fs_root); 4199d7ce5843SMiao Xie else 4200c71bf099SYan, Zheng btrfs_orphan_cleanup(fs_root); 42015d4f98a2SYan Zheng } 42025d4f98a2SYan Zheng return err; 42035d4f98a2SYan Zheng } 42045d4f98a2SYan Zheng 42055d4f98a2SYan Zheng /* 42065d4f98a2SYan Zheng * helper to add ordered checksum for data relocation. 42075d4f98a2SYan Zheng * 42085d4f98a2SYan Zheng * cloning checksum properly handles the nodatasum extents. 42095d4f98a2SYan Zheng * it also saves CPU time to re-calculate the checksum. 42105d4f98a2SYan Zheng */ 42115d4f98a2SYan Zheng int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) 42125d4f98a2SYan Zheng { 42135d4f98a2SYan Zheng struct btrfs_ordered_sum *sums; 42145d4f98a2SYan Zheng struct btrfs_sector_sum *sector_sum; 42155d4f98a2SYan Zheng struct btrfs_ordered_extent *ordered; 42165d4f98a2SYan Zheng struct btrfs_root *root = BTRFS_I(inode)->root; 42175d4f98a2SYan Zheng size_t offset; 42185d4f98a2SYan Zheng int ret; 42195d4f98a2SYan Zheng u64 disk_bytenr; 42205d4f98a2SYan Zheng LIST_HEAD(list); 42215d4f98a2SYan Zheng 42225d4f98a2SYan Zheng ordered = btrfs_lookup_ordered_extent(inode, file_pos); 42235d4f98a2SYan Zheng BUG_ON(ordered->file_offset != file_pos || ordered->len != len); 42245d4f98a2SYan Zheng 42255d4f98a2SYan Zheng disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; 42265d4f98a2SYan Zheng ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr, 42275d4f98a2SYan Zheng disk_bytenr + len - 1, &list); 42285d4f98a2SYan Zheng 42295d4f98a2SYan Zheng while (!list_empty(&list)) { 42305d4f98a2SYan Zheng sums = list_entry(list.next, struct btrfs_ordered_sum, list); 42315d4f98a2SYan Zheng list_del_init(&sums->list); 42325d4f98a2SYan Zheng 42335d4f98a2SYan Zheng sector_sum = sums->sums; 42345d4f98a2SYan Zheng sums->bytenr = ordered->start; 42355d4f98a2SYan Zheng 42365d4f98a2SYan Zheng offset = 0; 42375d4f98a2SYan Zheng while (offset < sums->len) { 42385d4f98a2SYan Zheng sector_sum->bytenr += ordered->start - disk_bytenr; 42395d4f98a2SYan Zheng sector_sum++; 42405d4f98a2SYan Zheng offset += root->sectorsize; 42415d4f98a2SYan Zheng } 42425d4f98a2SYan Zheng 42435d4f98a2SYan Zheng btrfs_add_ordered_sum(inode, ordered, sums); 42445d4f98a2SYan Zheng } 42455d4f98a2SYan Zheng btrfs_put_ordered_extent(ordered); 4246411fc6bcSAndi Kleen return ret; 42475d4f98a2SYan Zheng } 42483fd0a558SYan, Zheng 42493fd0a558SYan, Zheng void btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, 42503fd0a558SYan, Zheng struct btrfs_root *root, struct extent_buffer *buf, 42513fd0a558SYan, Zheng struct extent_buffer *cow) 42523fd0a558SYan, Zheng { 42533fd0a558SYan, Zheng struct reloc_control *rc; 42543fd0a558SYan, Zheng struct backref_node *node; 42553fd0a558SYan, Zheng int first_cow = 0; 42563fd0a558SYan, Zheng int level; 42573fd0a558SYan, Zheng int ret; 42583fd0a558SYan, Zheng 42593fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 42603fd0a558SYan, Zheng if (!rc) 42613fd0a558SYan, Zheng return; 42623fd0a558SYan, Zheng 42633fd0a558SYan, Zheng BUG_ON(rc->stage == UPDATE_DATA_PTRS && 42643fd0a558SYan, Zheng root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID); 42653fd0a558SYan, Zheng 42663fd0a558SYan, Zheng level = btrfs_header_level(buf); 42673fd0a558SYan, Zheng if (btrfs_header_generation(buf) <= 42683fd0a558SYan, Zheng btrfs_root_last_snapshot(&root->root_item)) 42693fd0a558SYan, Zheng first_cow = 1; 42703fd0a558SYan, Zheng 42713fd0a558SYan, Zheng if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID && 42723fd0a558SYan, Zheng rc->create_reloc_tree) { 42733fd0a558SYan, Zheng WARN_ON(!first_cow && level == 0); 42743fd0a558SYan, Zheng 42753fd0a558SYan, Zheng node = rc->backref_cache.path[level]; 42763fd0a558SYan, Zheng BUG_ON(node->bytenr != buf->start && 42773fd0a558SYan, Zheng node->new_bytenr != buf->start); 42783fd0a558SYan, Zheng 42793fd0a558SYan, Zheng drop_node_buffer(node); 42803fd0a558SYan, Zheng extent_buffer_get(cow); 42813fd0a558SYan, Zheng node->eb = cow; 42823fd0a558SYan, Zheng node->new_bytenr = cow->start; 42833fd0a558SYan, Zheng 42843fd0a558SYan, Zheng if (!node->pending) { 42853fd0a558SYan, Zheng list_move_tail(&node->list, 42863fd0a558SYan, Zheng &rc->backref_cache.pending[level]); 42873fd0a558SYan, Zheng node->pending = 1; 42883fd0a558SYan, Zheng } 42893fd0a558SYan, Zheng 42903fd0a558SYan, Zheng if (first_cow) 42913fd0a558SYan, Zheng __mark_block_processed(rc, node); 42923fd0a558SYan, Zheng 42933fd0a558SYan, Zheng if (first_cow && level > 0) 42943fd0a558SYan, Zheng rc->nodes_relocated += buf->len; 42953fd0a558SYan, Zheng } 42963fd0a558SYan, Zheng 42973fd0a558SYan, Zheng if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) { 42983fd0a558SYan, Zheng ret = replace_file_extents(trans, rc, root, cow); 42993fd0a558SYan, Zheng BUG_ON(ret); 43003fd0a558SYan, Zheng } 43013fd0a558SYan, Zheng } 43023fd0a558SYan, Zheng 43033fd0a558SYan, Zheng /* 43043fd0a558SYan, Zheng * called before creating snapshot. it calculates metadata reservation 43053fd0a558SYan, Zheng * requried for relocating tree blocks in the snapshot 43063fd0a558SYan, Zheng */ 43073fd0a558SYan, Zheng void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans, 43083fd0a558SYan, Zheng struct btrfs_pending_snapshot *pending, 43093fd0a558SYan, Zheng u64 *bytes_to_reserve) 43103fd0a558SYan, Zheng { 43113fd0a558SYan, Zheng struct btrfs_root *root; 43123fd0a558SYan, Zheng struct reloc_control *rc; 43133fd0a558SYan, Zheng 43143fd0a558SYan, Zheng root = pending->root; 43153fd0a558SYan, Zheng if (!root->reloc_root) 43163fd0a558SYan, Zheng return; 43173fd0a558SYan, Zheng 43183fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 43193fd0a558SYan, Zheng if (!rc->merge_reloc_tree) 43203fd0a558SYan, Zheng return; 43213fd0a558SYan, Zheng 43223fd0a558SYan, Zheng root = root->reloc_root; 43233fd0a558SYan, Zheng BUG_ON(btrfs_root_refs(&root->root_item) == 0); 43243fd0a558SYan, Zheng /* 43253fd0a558SYan, Zheng * relocation is in the stage of merging trees. the space 43263fd0a558SYan, Zheng * used by merging a reloc tree is twice the size of 43273fd0a558SYan, Zheng * relocated tree nodes in the worst case. half for cowing 43283fd0a558SYan, Zheng * the reloc tree, half for cowing the fs tree. the space 43293fd0a558SYan, Zheng * used by cowing the reloc tree will be freed after the 43303fd0a558SYan, Zheng * tree is dropped. if we create snapshot, cowing the fs 43313fd0a558SYan, Zheng * tree may use more space than it frees. so we need 43323fd0a558SYan, Zheng * reserve extra space. 43333fd0a558SYan, Zheng */ 43343fd0a558SYan, Zheng *bytes_to_reserve += rc->nodes_relocated; 43353fd0a558SYan, Zheng } 43363fd0a558SYan, Zheng 43373fd0a558SYan, Zheng /* 43383fd0a558SYan, Zheng * called after snapshot is created. migrate block reservation 43393fd0a558SYan, Zheng * and create reloc root for the newly created snapshot 43403fd0a558SYan, Zheng */ 43413fd0a558SYan, Zheng void btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, 43423fd0a558SYan, Zheng struct btrfs_pending_snapshot *pending) 43433fd0a558SYan, Zheng { 43443fd0a558SYan, Zheng struct btrfs_root *root = pending->root; 43453fd0a558SYan, Zheng struct btrfs_root *reloc_root; 43463fd0a558SYan, Zheng struct btrfs_root *new_root; 43473fd0a558SYan, Zheng struct reloc_control *rc; 43483fd0a558SYan, Zheng int ret; 43493fd0a558SYan, Zheng 43503fd0a558SYan, Zheng if (!root->reloc_root) 43513fd0a558SYan, Zheng return; 43523fd0a558SYan, Zheng 43533fd0a558SYan, Zheng rc = root->fs_info->reloc_ctl; 43543fd0a558SYan, Zheng rc->merging_rsv_size += rc->nodes_relocated; 43553fd0a558SYan, Zheng 43563fd0a558SYan, Zheng if (rc->merge_reloc_tree) { 43573fd0a558SYan, Zheng ret = btrfs_block_rsv_migrate(&pending->block_rsv, 43583fd0a558SYan, Zheng rc->block_rsv, 43593fd0a558SYan, Zheng rc->nodes_relocated); 43603fd0a558SYan, Zheng BUG_ON(ret); 43613fd0a558SYan, Zheng } 43623fd0a558SYan, Zheng 43633fd0a558SYan, Zheng new_root = pending->snap; 43643fd0a558SYan, Zheng reloc_root = create_reloc_root(trans, root->reloc_root, 43653fd0a558SYan, Zheng new_root->root_key.objectid); 43663fd0a558SYan, Zheng 43673fd0a558SYan, Zheng __add_reloc_root(reloc_root); 43683fd0a558SYan, Zheng new_root->reloc_root = reloc_root; 43693fd0a558SYan, Zheng 43703fd0a558SYan, Zheng if (rc->create_reloc_tree) { 43713fd0a558SYan, Zheng ret = clone_backref_node(trans, rc, root, reloc_root); 43723fd0a558SYan, Zheng BUG_ON(ret); 43733fd0a558SYan, Zheng } 43743fd0a558SYan, Zheng } 4375