16cbd5570SChris Mason /* 26cbd5570SChris Mason * Copyright (C) 2007 Oracle. All rights reserved. 36cbd5570SChris Mason * 46cbd5570SChris Mason * This program is free software; you can redistribute it and/or 56cbd5570SChris Mason * modify it under the terms of the GNU General Public 66cbd5570SChris Mason * License v2 as published by the Free Software Foundation. 76cbd5570SChris Mason * 86cbd5570SChris Mason * This program is distributed in the hope that it will be useful, 96cbd5570SChris Mason * but WITHOUT ANY WARRANTY; without even the implied warranty of 106cbd5570SChris Mason * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 116cbd5570SChris Mason * General Public License for more details. 126cbd5570SChris Mason * 136cbd5570SChris Mason * You should have received a copy of the GNU General Public 146cbd5570SChris Mason * License along with this program; if not, write to the 156cbd5570SChris Mason * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 166cbd5570SChris Mason * Boston, MA 021110-1307, USA. 176cbd5570SChris Mason */ 186cbd5570SChris Mason 1979154b1bSChris Mason #include <linux/fs.h> 2034088780SChris Mason #include <linux/sched.h> 21d3c2fdcfSChris Mason #include <linux/writeback.h> 225f39d397SChris Mason #include <linux/pagemap.h> 2379154b1bSChris Mason #include "ctree.h" 2479154b1bSChris Mason #include "disk-io.h" 2579154b1bSChris Mason #include "transaction.h" 26925baeddSChris Mason #include "locking.h" 2731153d81SYan Zheng #include "ref-cache.h" 2879154b1bSChris Mason 2978fae27eSChris Mason static int total_trans = 0; 302c90e5d6SChris Mason extern struct kmem_cache *btrfs_trans_handle_cachep; 312c90e5d6SChris Mason extern struct kmem_cache *btrfs_transaction_cachep; 322c90e5d6SChris Mason 330f7d52f4SChris Mason #define BTRFS_ROOT_TRANS_TAG 0 340f7d52f4SChris Mason 3580b6794dSChris Mason static noinline void put_transaction(struct btrfs_transaction *transaction) 3679154b1bSChris Mason { 372c90e5d6SChris Mason WARN_ON(transaction->use_count == 0); 3879154b1bSChris Mason transaction->use_count--; 3978fae27eSChris Mason if (transaction->use_count == 0) { 4078fae27eSChris Mason WARN_ON(total_trans == 0); 4178fae27eSChris Mason total_trans--; 428fd17795SChris Mason list_del_init(&transaction->list); 432c90e5d6SChris Mason memset(transaction, 0, sizeof(*transaction)); 442c90e5d6SChris Mason kmem_cache_free(btrfs_transaction_cachep, transaction); 4579154b1bSChris Mason } 4678fae27eSChris Mason } 4779154b1bSChris Mason 4880b6794dSChris Mason static noinline int join_transaction(struct btrfs_root *root) 4979154b1bSChris Mason { 5079154b1bSChris Mason struct btrfs_transaction *cur_trans; 5179154b1bSChris Mason cur_trans = root->fs_info->running_transaction; 5279154b1bSChris Mason if (!cur_trans) { 532c90e5d6SChris Mason cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, 542c90e5d6SChris Mason GFP_NOFS); 5578fae27eSChris Mason total_trans++; 5679154b1bSChris Mason BUG_ON(!cur_trans); 570f7d52f4SChris Mason root->fs_info->generation++; 58e18e4809SChris Mason root->fs_info->last_alloc = 0; 594529ba49SChris Mason root->fs_info->last_data_alloc = 0; 6015ee9bc7SJosef Bacik cur_trans->num_writers = 1; 6115ee9bc7SJosef Bacik cur_trans->num_joined = 0; 620f7d52f4SChris Mason cur_trans->transid = root->fs_info->generation; 6379154b1bSChris Mason init_waitqueue_head(&cur_trans->writer_wait); 6479154b1bSChris Mason init_waitqueue_head(&cur_trans->commit_wait); 6579154b1bSChris Mason cur_trans->in_commit = 0; 66f9295749SChris Mason cur_trans->blocked = 0; 67d5719762SChris Mason cur_trans->use_count = 1; 6879154b1bSChris Mason cur_trans->commit_done = 0; 6908607c1bSChris Mason cur_trans->start_time = get_seconds(); 703063d29fSChris Mason INIT_LIST_HEAD(&cur_trans->pending_snapshots); 718fd17795SChris Mason list_add_tail(&cur_trans->list, &root->fs_info->trans_list); 72d1310b2eSChris Mason extent_io_tree_init(&cur_trans->dirty_pages, 735f39d397SChris Mason root->fs_info->btree_inode->i_mapping, 745f39d397SChris Mason GFP_NOFS); 7548ec2cf8SChris Mason spin_lock(&root->fs_info->new_trans_lock); 7648ec2cf8SChris Mason root->fs_info->running_transaction = cur_trans; 7748ec2cf8SChris Mason spin_unlock(&root->fs_info->new_trans_lock); 7815ee9bc7SJosef Bacik } else { 7979154b1bSChris Mason cur_trans->num_writers++; 8015ee9bc7SJosef Bacik cur_trans->num_joined++; 8115ee9bc7SJosef Bacik } 8215ee9bc7SJosef Bacik 8379154b1bSChris Mason return 0; 8479154b1bSChris Mason } 8579154b1bSChris Mason 8680b6794dSChris Mason static noinline int record_root_in_trans(struct btrfs_root *root) 876702ed49SChris Mason { 88f321e491SYan Zheng struct btrfs_dirty_root *dirty; 896702ed49SChris Mason u64 running_trans_id = root->fs_info->running_transaction->transid; 906702ed49SChris Mason if (root->ref_cows && root->last_trans < running_trans_id) { 916702ed49SChris Mason WARN_ON(root == root->fs_info->extent_root); 926702ed49SChris Mason if (root->root_item.refs != 0) { 936702ed49SChris Mason radix_tree_tag_set(&root->fs_info->fs_roots_radix, 946702ed49SChris Mason (unsigned long)root->root_key.objectid, 956702ed49SChris Mason BTRFS_ROOT_TRANS_TAG); 9631153d81SYan Zheng 9731153d81SYan Zheng dirty = kmalloc(sizeof(*dirty), GFP_NOFS); 9831153d81SYan Zheng BUG_ON(!dirty); 9931153d81SYan Zheng dirty->root = kmalloc(sizeof(*dirty->root), GFP_NOFS); 10031153d81SYan Zheng BUG_ON(!dirty->root); 10131153d81SYan Zheng 10231153d81SYan Zheng dirty->latest_root = root; 10331153d81SYan Zheng INIT_LIST_HEAD(&dirty->list); 10431153d81SYan Zheng 105925baeddSChris Mason root->commit_root = btrfs_root_node(root); 106017e5369SChris Mason root->dirty_root = dirty; 10731153d81SYan Zheng 10831153d81SYan Zheng memcpy(dirty->root, root, sizeof(*root)); 109017e5369SChris Mason dirty->root->ref_tree = &root->ref_tree_struct; 110017e5369SChris Mason 11131153d81SYan Zheng spin_lock_init(&dirty->root->node_lock); 11231153d81SYan Zheng mutex_init(&dirty->root->objectid_mutex); 11331153d81SYan Zheng dirty->root->node = root->commit_root; 11431153d81SYan Zheng dirty->root->commit_root = NULL; 1156702ed49SChris Mason } else { 1166702ed49SChris Mason WARN_ON(1); 1176702ed49SChris Mason } 1186702ed49SChris Mason root->last_trans = running_trans_id; 1196702ed49SChris Mason } 1206702ed49SChris Mason return 0; 1216702ed49SChris Mason } 1226702ed49SChris Mason 123f9295749SChris Mason struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, 124f9295749SChris Mason int num_blocks, int join) 12579154b1bSChris Mason { 1262c90e5d6SChris Mason struct btrfs_trans_handle *h = 1272c90e5d6SChris Mason kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); 128f9295749SChris Mason struct btrfs_transaction *cur_trans; 12979154b1bSChris Mason int ret; 13079154b1bSChris Mason 13179154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 132f9295749SChris Mason cur_trans = root->fs_info->running_transaction; 133f9295749SChris Mason if (cur_trans && cur_trans->blocked && !join) { 134f9295749SChris Mason DEFINE_WAIT(wait); 135f9295749SChris Mason cur_trans->use_count++; 136f9295749SChris Mason while(1) { 137f9295749SChris Mason prepare_to_wait(&root->fs_info->transaction_wait, &wait, 138f9295749SChris Mason TASK_UNINTERRUPTIBLE); 139f9295749SChris Mason if (cur_trans->blocked) { 140f9295749SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 141f9295749SChris Mason schedule(); 142f9295749SChris Mason mutex_lock(&root->fs_info->trans_mutex); 143f9295749SChris Mason finish_wait(&root->fs_info->transaction_wait, 144f9295749SChris Mason &wait); 145f9295749SChris Mason } else { 146f9295749SChris Mason finish_wait(&root->fs_info->transaction_wait, 147f9295749SChris Mason &wait); 148f9295749SChris Mason break; 149f9295749SChris Mason } 150f9295749SChris Mason } 151f9295749SChris Mason put_transaction(cur_trans); 152f9295749SChris Mason } 15379154b1bSChris Mason ret = join_transaction(root); 15479154b1bSChris Mason BUG_ON(ret); 1550f7d52f4SChris Mason 1566702ed49SChris Mason record_root_in_trans(root); 1576702ed49SChris Mason h->transid = root->fs_info->running_transaction->transid; 15879154b1bSChris Mason h->transaction = root->fs_info->running_transaction; 15979154b1bSChris Mason h->blocks_reserved = num_blocks; 16079154b1bSChris Mason h->blocks_used = 0; 16131f3c99bSChris Mason h->block_group = NULL; 16226b8003fSChris Mason h->alloc_exclude_nr = 0; 16326b8003fSChris Mason h->alloc_exclude_start = 0; 16479154b1bSChris Mason root->fs_info->running_transaction->use_count++; 16579154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 16679154b1bSChris Mason return h; 16779154b1bSChris Mason } 16879154b1bSChris Mason 169f9295749SChris Mason struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 170f9295749SChris Mason int num_blocks) 171f9295749SChris Mason { 172f9295749SChris Mason return start_transaction(root, num_blocks, 0); 173f9295749SChris Mason } 174f9295749SChris Mason struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, 175f9295749SChris Mason int num_blocks) 176f9295749SChris Mason { 177f9295749SChris Mason return start_transaction(root, num_blocks, 1); 178f9295749SChris Mason } 179f9295749SChris Mason 18089ce8a63SChris Mason static noinline int wait_for_commit(struct btrfs_root *root, 18189ce8a63SChris Mason struct btrfs_transaction *commit) 18289ce8a63SChris Mason { 18389ce8a63SChris Mason DEFINE_WAIT(wait); 18489ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 18589ce8a63SChris Mason while(!commit->commit_done) { 18689ce8a63SChris Mason prepare_to_wait(&commit->commit_wait, &wait, 18789ce8a63SChris Mason TASK_UNINTERRUPTIBLE); 18889ce8a63SChris Mason if (commit->commit_done) 18989ce8a63SChris Mason break; 19089ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 19189ce8a63SChris Mason schedule(); 19289ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 19389ce8a63SChris Mason } 19489ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 19589ce8a63SChris Mason finish_wait(&commit->commit_wait, &wait); 19689ce8a63SChris Mason return 0; 19789ce8a63SChris Mason } 19889ce8a63SChris Mason 199ab78c84dSChris Mason void btrfs_throttle(struct btrfs_root *root) 200ab78c84dSChris Mason { 201ab78c84dSChris Mason struct btrfs_fs_info *info = root->fs_info; 202ab78c84dSChris Mason 203ab78c84dSChris Mason harder: 204ab78c84dSChris Mason if (atomic_read(&info->throttles)) { 205ab78c84dSChris Mason DEFINE_WAIT(wait); 206ab78c84dSChris Mason int thr; 207ab78c84dSChris Mason int harder_count = 0; 208ab78c84dSChris Mason thr = atomic_read(&info->throttle_gen); 209ab78c84dSChris Mason 210ab78c84dSChris Mason do { 211ab78c84dSChris Mason prepare_to_wait(&info->transaction_throttle, 212ab78c84dSChris Mason &wait, TASK_UNINTERRUPTIBLE); 213ab78c84dSChris Mason if (!atomic_read(&info->throttles)) { 214ab78c84dSChris Mason finish_wait(&info->transaction_throttle, &wait); 215ab78c84dSChris Mason break; 216ab78c84dSChris Mason } 217ab78c84dSChris Mason schedule(); 218ab78c84dSChris Mason finish_wait(&info->transaction_throttle, &wait); 219ab78c84dSChris Mason } while (thr == atomic_read(&info->throttle_gen)); 220ab78c84dSChris Mason 221ab78c84dSChris Mason if (harder_count < 5 && 222ab78c84dSChris Mason info->total_ref_cache_size > 5 * 1024 * 1024) { 223ab78c84dSChris Mason harder_count++; 224ab78c84dSChris Mason goto harder; 225ab78c84dSChris Mason } 226ab78c84dSChris Mason 227ab78c84dSChris Mason if (harder_count < 10 && 228ab78c84dSChris Mason info->total_ref_cache_size > 10 * 1024 * 1024) { 229ab78c84dSChris Mason harder_count++; 230ab78c84dSChris Mason goto harder; 231ab78c84dSChris Mason } 232ab78c84dSChris Mason } 233ab78c84dSChris Mason } 234ab78c84dSChris Mason 23589ce8a63SChris Mason static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, 23689ce8a63SChris Mason struct btrfs_root *root, int throttle) 23779154b1bSChris Mason { 23879154b1bSChris Mason struct btrfs_transaction *cur_trans; 239ab78c84dSChris Mason struct btrfs_fs_info *info = root->fs_info; 240d6e4a428SChris Mason 241ab78c84dSChris Mason mutex_lock(&info->trans_mutex); 242ab78c84dSChris Mason cur_trans = info->running_transaction; 243ccd467d6SChris Mason WARN_ON(cur_trans != trans->transaction); 244d5719762SChris Mason WARN_ON(cur_trans->num_writers < 1); 245ccd467d6SChris Mason cur_trans->num_writers--; 24689ce8a63SChris Mason 24779154b1bSChris Mason if (waitqueue_active(&cur_trans->writer_wait)) 24879154b1bSChris Mason wake_up(&cur_trans->writer_wait); 24979154b1bSChris Mason put_transaction(cur_trans); 250ab78c84dSChris Mason mutex_unlock(&info->trans_mutex); 251d6025579SChris Mason memset(trans, 0, sizeof(*trans)); 2522c90e5d6SChris Mason kmem_cache_free(btrfs_trans_handle_cachep, trans); 253ab78c84dSChris Mason 254ab78c84dSChris Mason if (throttle) 255ab78c84dSChris Mason btrfs_throttle(root); 256ab78c84dSChris Mason 25779154b1bSChris Mason return 0; 25879154b1bSChris Mason } 25979154b1bSChris Mason 26089ce8a63SChris Mason int btrfs_end_transaction(struct btrfs_trans_handle *trans, 26189ce8a63SChris Mason struct btrfs_root *root) 26289ce8a63SChris Mason { 26389ce8a63SChris Mason return __btrfs_end_transaction(trans, root, 0); 26489ce8a63SChris Mason } 26589ce8a63SChris Mason 26689ce8a63SChris Mason int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, 26789ce8a63SChris Mason struct btrfs_root *root) 26889ce8a63SChris Mason { 26989ce8a63SChris Mason return __btrfs_end_transaction(trans, root, 1); 27089ce8a63SChris Mason } 27189ce8a63SChris Mason 27279154b1bSChris Mason 27379154b1bSChris Mason int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, 27479154b1bSChris Mason struct btrfs_root *root) 27579154b1bSChris Mason { 2767c4452b9SChris Mason int ret; 2777c4452b9SChris Mason int err; 2787c4452b9SChris Mason int werr = 0; 279d1310b2eSChris Mason struct extent_io_tree *dirty_pages; 2807c4452b9SChris Mason struct page *page; 2817c4452b9SChris Mason struct inode *btree_inode = root->fs_info->btree_inode; 2825f39d397SChris Mason u64 start; 2835f39d397SChris Mason u64 end; 2845f39d397SChris Mason unsigned long index; 2857c4452b9SChris Mason 2867c4452b9SChris Mason if (!trans || !trans->transaction) { 2877c4452b9SChris Mason return filemap_write_and_wait(btree_inode->i_mapping); 2887c4452b9SChris Mason } 2897c4452b9SChris Mason dirty_pages = &trans->transaction->dirty_pages; 2907c4452b9SChris Mason while(1) { 2915f39d397SChris Mason ret = find_first_extent_bit(dirty_pages, 0, &start, &end, 2925f39d397SChris Mason EXTENT_DIRTY); 2935f39d397SChris Mason if (ret) 2947c4452b9SChris Mason break; 2955f39d397SChris Mason clear_extent_dirty(dirty_pages, start, end, GFP_NOFS); 2965f39d397SChris Mason while(start <= end) { 2975f39d397SChris Mason index = start >> PAGE_CACHE_SHIFT; 29835ebb934SChris Mason start = (u64)(index + 1) << PAGE_CACHE_SHIFT; 2995f39d397SChris Mason page = find_lock_page(btree_inode->i_mapping, index); 3007c4452b9SChris Mason if (!page) 3017c4452b9SChris Mason continue; 3026702ed49SChris Mason if (PageWriteback(page)) { 3036702ed49SChris Mason if (PageDirty(page)) 3046702ed49SChris Mason wait_on_page_writeback(page); 3056702ed49SChris Mason else { 3066702ed49SChris Mason unlock_page(page); 3076702ed49SChris Mason page_cache_release(page); 3086702ed49SChris Mason continue; 3096702ed49SChris Mason } 3106702ed49SChris Mason } 3117c4452b9SChris Mason err = write_one_page(page, 0); 3127c4452b9SChris Mason if (err) 3137c4452b9SChris Mason werr = err; 3147c4452b9SChris Mason page_cache_release(page); 3157c4452b9SChris Mason } 3167c4452b9SChris Mason } 3177c4452b9SChris Mason err = filemap_fdatawait(btree_inode->i_mapping); 3187c4452b9SChris Mason if (err) 3197c4452b9SChris Mason werr = err; 3207c4452b9SChris Mason return werr; 32179154b1bSChris Mason } 32279154b1bSChris Mason 3230b86a832SChris Mason static int update_cowonly_root(struct btrfs_trans_handle *trans, 32479154b1bSChris Mason struct btrfs_root *root) 32579154b1bSChris Mason { 32679154b1bSChris Mason int ret; 3270b86a832SChris Mason u64 old_root_bytenr; 3280b86a832SChris Mason struct btrfs_root *tree_root = root->fs_info->tree_root; 32979154b1bSChris Mason 3300b86a832SChris Mason btrfs_write_dirty_block_groups(trans, root); 33179154b1bSChris Mason while(1) { 3320b86a832SChris Mason old_root_bytenr = btrfs_root_bytenr(&root->root_item); 3330b86a832SChris Mason if (old_root_bytenr == root->node->start) 33479154b1bSChris Mason break; 3350b86a832SChris Mason btrfs_set_root_bytenr(&root->root_item, 3360b86a832SChris Mason root->node->start); 3370b86a832SChris Mason btrfs_set_root_level(&root->root_item, 3380b86a832SChris Mason btrfs_header_level(root->node)); 33979154b1bSChris Mason ret = btrfs_update_root(trans, tree_root, 3400b86a832SChris Mason &root->root_key, 3410b86a832SChris Mason &root->root_item); 34279154b1bSChris Mason BUG_ON(ret); 3430b86a832SChris Mason btrfs_write_dirty_block_groups(trans, root); 3440b86a832SChris Mason } 3450b86a832SChris Mason return 0; 3460b86a832SChris Mason } 3470b86a832SChris Mason 3480b86a832SChris Mason int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans, 3490b86a832SChris Mason struct btrfs_root *root) 3500b86a832SChris Mason { 3510b86a832SChris Mason struct btrfs_fs_info *fs_info = root->fs_info; 3520b86a832SChris Mason struct list_head *next; 3530b86a832SChris Mason 3540b86a832SChris Mason while(!list_empty(&fs_info->dirty_cowonly_roots)) { 3550b86a832SChris Mason next = fs_info->dirty_cowonly_roots.next; 3560b86a832SChris Mason list_del_init(next); 3570b86a832SChris Mason root = list_entry(next, struct btrfs_root, dirty_list); 3580b86a832SChris Mason update_cowonly_root(trans, root); 359017e5369SChris Mason if (root->fs_info->closing) 360017e5369SChris Mason btrfs_remove_leaf_refs(root); 36179154b1bSChris Mason } 36279154b1bSChris Mason return 0; 36379154b1bSChris Mason } 36479154b1bSChris Mason 3655ce14bbcSChris Mason int btrfs_add_dead_root(struct btrfs_root *root, 3665ce14bbcSChris Mason struct btrfs_root *latest, 3675ce14bbcSChris Mason struct list_head *dead_list) 3685eda7b5eSChris Mason { 369f321e491SYan Zheng struct btrfs_dirty_root *dirty; 3705eda7b5eSChris Mason 3715eda7b5eSChris Mason dirty = kmalloc(sizeof(*dirty), GFP_NOFS); 3725eda7b5eSChris Mason if (!dirty) 3735eda7b5eSChris Mason return -ENOMEM; 3745eda7b5eSChris Mason dirty->root = root; 3755ce14bbcSChris Mason dirty->latest_root = latest; 3765eda7b5eSChris Mason list_add(&dirty->list, dead_list); 3775eda7b5eSChris Mason return 0; 3785eda7b5eSChris Mason } 3795eda7b5eSChris Mason 38080b6794dSChris Mason static noinline int add_dirty_roots(struct btrfs_trans_handle *trans, 38135b7e476SChris Mason struct radix_tree_root *radix, 38235b7e476SChris Mason struct list_head *list) 3830f7d52f4SChris Mason { 384f321e491SYan Zheng struct btrfs_dirty_root *dirty; 3850f7d52f4SChris Mason struct btrfs_root *gang[8]; 3860f7d52f4SChris Mason struct btrfs_root *root; 3870f7d52f4SChris Mason int i; 3880f7d52f4SChris Mason int ret; 38954aa1f4dSChris Mason int err = 0; 3905eda7b5eSChris Mason u32 refs; 39154aa1f4dSChris Mason 3920f7d52f4SChris Mason while(1) { 3930f7d52f4SChris Mason ret = radix_tree_gang_lookup_tag(radix, (void **)gang, 0, 3940f7d52f4SChris Mason ARRAY_SIZE(gang), 3950f7d52f4SChris Mason BTRFS_ROOT_TRANS_TAG); 3960f7d52f4SChris Mason if (ret == 0) 3970f7d52f4SChris Mason break; 3980f7d52f4SChris Mason for (i = 0; i < ret; i++) { 3990f7d52f4SChris Mason root = gang[i]; 4002619ba1fSChris Mason radix_tree_tag_clear(radix, 4012619ba1fSChris Mason (unsigned long)root->root_key.objectid, 4020f7d52f4SChris Mason BTRFS_ROOT_TRANS_TAG); 40331153d81SYan Zheng 40431153d81SYan Zheng BUG_ON(!root->ref_tree); 405017e5369SChris Mason dirty = root->dirty_root; 40631153d81SYan Zheng 4070f7d52f4SChris Mason if (root->commit_root == root->node) { 408db94535dSChris Mason WARN_ON(root->node->start != 409db94535dSChris Mason btrfs_root_bytenr(&root->root_item)); 41031153d81SYan Zheng 4115f39d397SChris Mason free_extent_buffer(root->commit_root); 4120f7d52f4SChris Mason root->commit_root = NULL; 41331153d81SYan Zheng 41431153d81SYan Zheng kfree(dirty->root); 41531153d81SYan Zheng kfree(dirty); 41658176a96SJosef Bacik 41758176a96SJosef Bacik /* make sure to update the root on disk 41858176a96SJosef Bacik * so we get any updates to the block used 41958176a96SJosef Bacik * counts 42058176a96SJosef Bacik */ 42158176a96SJosef Bacik err = btrfs_update_root(trans, 42258176a96SJosef Bacik root->fs_info->tree_root, 42358176a96SJosef Bacik &root->root_key, 42458176a96SJosef Bacik &root->root_item); 4250f7d52f4SChris Mason continue; 4260f7d52f4SChris Mason } 4279f3a7427SChris Mason 4289f3a7427SChris Mason memset(&root->root_item.drop_progress, 0, 4299f3a7427SChris Mason sizeof(struct btrfs_disk_key)); 4309f3a7427SChris Mason root->root_item.drop_level = 0; 4310f7d52f4SChris Mason root->commit_root = NULL; 4320f7d52f4SChris Mason root->root_key.offset = root->fs_info->generation; 433db94535dSChris Mason btrfs_set_root_bytenr(&root->root_item, 434db94535dSChris Mason root->node->start); 435db94535dSChris Mason btrfs_set_root_level(&root->root_item, 436db94535dSChris Mason btrfs_header_level(root->node)); 4370f7d52f4SChris Mason err = btrfs_insert_root(trans, root->fs_info->tree_root, 4380f7d52f4SChris Mason &root->root_key, 4390f7d52f4SChris Mason &root->root_item); 44054aa1f4dSChris Mason if (err) 44154aa1f4dSChris Mason break; 4429f3a7427SChris Mason 4439f3a7427SChris Mason refs = btrfs_root_refs(&dirty->root->root_item); 4449f3a7427SChris Mason btrfs_set_root_refs(&dirty->root->root_item, refs - 1); 4455eda7b5eSChris Mason err = btrfs_update_root(trans, root->fs_info->tree_root, 4469f3a7427SChris Mason &dirty->root->root_key, 4479f3a7427SChris Mason &dirty->root->root_item); 4485eda7b5eSChris Mason 4495eda7b5eSChris Mason BUG_ON(err); 4509f3a7427SChris Mason if (refs == 1) { 4510f7d52f4SChris Mason list_add(&dirty->list, list); 4529f3a7427SChris Mason } else { 4539f3a7427SChris Mason WARN_ON(1); 45431153d81SYan Zheng free_extent_buffer(dirty->root->node); 4559f3a7427SChris Mason kfree(dirty->root); 4565eda7b5eSChris Mason kfree(dirty); 4570f7d52f4SChris Mason } 4580f7d52f4SChris Mason } 4599f3a7427SChris Mason } 46054aa1f4dSChris Mason return err; 4610f7d52f4SChris Mason } 4620f7d52f4SChris Mason 463e9d0b13bSChris Mason int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) 464e9d0b13bSChris Mason { 465e9d0b13bSChris Mason struct btrfs_fs_info *info = root->fs_info; 466e9d0b13bSChris Mason int ret; 467e9d0b13bSChris Mason struct btrfs_trans_handle *trans; 468d3c2fdcfSChris Mason unsigned long nr; 469e9d0b13bSChris Mason 470a2135011SChris Mason smp_mb(); 471e9d0b13bSChris Mason if (root->defrag_running) 472e9d0b13bSChris Mason return 0; 473e9d0b13bSChris Mason trans = btrfs_start_transaction(root, 1); 4746b80053dSChris Mason while (1) { 475e9d0b13bSChris Mason root->defrag_running = 1; 476e9d0b13bSChris Mason ret = btrfs_defrag_leaves(trans, root, cacheonly); 477d3c2fdcfSChris Mason nr = trans->blocks_used; 478e9d0b13bSChris Mason btrfs_end_transaction(trans, root); 479d3c2fdcfSChris Mason btrfs_btree_balance_dirty(info->tree_root, nr); 480e9d0b13bSChris Mason cond_resched(); 481e9d0b13bSChris Mason 482e9d0b13bSChris Mason trans = btrfs_start_transaction(root, 1); 4833f157a2fSChris Mason if (root->fs_info->closing || ret != -EAGAIN) 484e9d0b13bSChris Mason break; 485e9d0b13bSChris Mason } 486e9d0b13bSChris Mason root->defrag_running = 0; 487a2135011SChris Mason smp_mb(); 488e9d0b13bSChris Mason btrfs_end_transaction(trans, root); 489e9d0b13bSChris Mason return 0; 490e9d0b13bSChris Mason } 491e9d0b13bSChris Mason 49280b6794dSChris Mason static noinline int drop_dirty_roots(struct btrfs_root *tree_root, 49335b7e476SChris Mason struct list_head *list) 4940f7d52f4SChris Mason { 495f321e491SYan Zheng struct btrfs_dirty_root *dirty; 4960f7d52f4SChris Mason struct btrfs_trans_handle *trans; 497d3c2fdcfSChris Mason unsigned long nr; 498db94535dSChris Mason u64 num_bytes; 499db94535dSChris Mason u64 bytes_used; 50054aa1f4dSChris Mason int ret = 0; 5019f3a7427SChris Mason int err; 5029f3a7427SChris Mason 5030f7d52f4SChris Mason while(!list_empty(list)) { 50458176a96SJosef Bacik struct btrfs_root *root; 50558176a96SJosef Bacik 506f321e491SYan Zheng dirty = list_entry(list->prev, struct btrfs_dirty_root, list); 5070f7d52f4SChris Mason list_del_init(&dirty->list); 5085eda7b5eSChris Mason 509db94535dSChris Mason num_bytes = btrfs_root_used(&dirty->root->root_item); 51058176a96SJosef Bacik root = dirty->latest_root; 511a2135011SChris Mason atomic_inc(&root->fs_info->throttles); 51258176a96SJosef Bacik 513a2135011SChris Mason mutex_lock(&root->fs_info->drop_mutex); 5149f3a7427SChris Mason while(1) { 5150f7d52f4SChris Mason trans = btrfs_start_transaction(tree_root, 1); 5169f3a7427SChris Mason ret = btrfs_drop_snapshot(trans, dirty->root); 5179f3a7427SChris Mason if (ret != -EAGAIN) { 5189f3a7427SChris Mason break; 5199f3a7427SChris Mason } 52058176a96SJosef Bacik 5219f3a7427SChris Mason err = btrfs_update_root(trans, 5229f3a7427SChris Mason tree_root, 5239f3a7427SChris Mason &dirty->root->root_key, 5249f3a7427SChris Mason &dirty->root->root_item); 5259f3a7427SChris Mason if (err) 5269f3a7427SChris Mason ret = err; 527d3c2fdcfSChris Mason nr = trans->blocks_used; 528017e5369SChris Mason ret = btrfs_end_transaction(trans, tree_root); 5290f7d52f4SChris Mason BUG_ON(ret); 530a2135011SChris Mason 531a2135011SChris Mason mutex_unlock(&root->fs_info->drop_mutex); 532d3c2fdcfSChris Mason btrfs_btree_balance_dirty(tree_root, nr); 5334dc11904SChris Mason cond_resched(); 534a2135011SChris Mason mutex_lock(&root->fs_info->drop_mutex); 5359f3a7427SChris Mason } 5369f3a7427SChris Mason BUG_ON(ret); 537a2135011SChris Mason atomic_dec(&root->fs_info->throttles); 538017e5369SChris Mason wake_up(&root->fs_info->transaction_throttle); 53958176a96SJosef Bacik 540a2135011SChris Mason mutex_lock(&root->fs_info->alloc_mutex); 541db94535dSChris Mason num_bytes -= btrfs_root_used(&dirty->root->root_item); 542db94535dSChris Mason bytes_used = btrfs_root_used(&root->root_item); 543db94535dSChris Mason if (num_bytes) { 54458176a96SJosef Bacik record_root_in_trans(root); 5455f39d397SChris Mason btrfs_set_root_used(&root->root_item, 546db94535dSChris Mason bytes_used - num_bytes); 54758176a96SJosef Bacik } 548a2135011SChris Mason mutex_unlock(&root->fs_info->alloc_mutex); 549a2135011SChris Mason 5509f3a7427SChris Mason ret = btrfs_del_root(trans, tree_root, &dirty->root->root_key); 55158176a96SJosef Bacik if (ret) { 55258176a96SJosef Bacik BUG(); 55354aa1f4dSChris Mason break; 55458176a96SJosef Bacik } 555a2135011SChris Mason mutex_unlock(&root->fs_info->drop_mutex); 556a2135011SChris Mason 557d3c2fdcfSChris Mason nr = trans->blocks_used; 5580f7d52f4SChris Mason ret = btrfs_end_transaction(trans, tree_root); 5590f7d52f4SChris Mason BUG_ON(ret); 5605eda7b5eSChris Mason 561f510cfecSChris Mason free_extent_buffer(dirty->root->node); 5625eda7b5eSChris Mason kfree(dirty->root); 5630f7d52f4SChris Mason kfree(dirty); 564d3c2fdcfSChris Mason 565d3c2fdcfSChris Mason btrfs_btree_balance_dirty(tree_root, nr); 5664dc11904SChris Mason cond_resched(); 5670f7d52f4SChris Mason } 56854aa1f4dSChris Mason return ret; 5690f7d52f4SChris Mason } 5700f7d52f4SChris Mason 57180b6794dSChris Mason static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, 5723063d29fSChris Mason struct btrfs_fs_info *fs_info, 5733063d29fSChris Mason struct btrfs_pending_snapshot *pending) 5743063d29fSChris Mason { 5753063d29fSChris Mason struct btrfs_key key; 57680b6794dSChris Mason struct btrfs_root_item *new_root_item; 5773063d29fSChris Mason struct btrfs_root *tree_root = fs_info->tree_root; 5783063d29fSChris Mason struct btrfs_root *root = pending->root; 5793063d29fSChris Mason struct extent_buffer *tmp; 580925baeddSChris Mason struct extent_buffer *old; 5813063d29fSChris Mason int ret; 5823b96362cSSven Wegener int namelen; 5833063d29fSChris Mason u64 objectid; 5843063d29fSChris Mason 58580b6794dSChris Mason new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); 58680b6794dSChris Mason if (!new_root_item) { 58780b6794dSChris Mason ret = -ENOMEM; 58880b6794dSChris Mason goto fail; 58980b6794dSChris Mason } 5903063d29fSChris Mason ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); 5913063d29fSChris Mason if (ret) 5923063d29fSChris Mason goto fail; 5933063d29fSChris Mason 59480b6794dSChris Mason memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); 5953063d29fSChris Mason 5963063d29fSChris Mason key.objectid = objectid; 5973063d29fSChris Mason key.offset = 1; 5983063d29fSChris Mason btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); 5993063d29fSChris Mason 600925baeddSChris Mason old = btrfs_lock_root_node(root); 601925baeddSChris Mason btrfs_cow_block(trans, root, old, NULL, 0, &old); 6023063d29fSChris Mason 603925baeddSChris Mason btrfs_copy_root(trans, root, old, &tmp, objectid); 604925baeddSChris Mason btrfs_tree_unlock(old); 605925baeddSChris Mason free_extent_buffer(old); 6063063d29fSChris Mason 60780b6794dSChris Mason btrfs_set_root_bytenr(new_root_item, tmp->start); 60880b6794dSChris Mason btrfs_set_root_level(new_root_item, btrfs_header_level(tmp)); 6093063d29fSChris Mason ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 61080b6794dSChris Mason new_root_item); 611925baeddSChris Mason btrfs_tree_unlock(tmp); 6123063d29fSChris Mason free_extent_buffer(tmp); 6133063d29fSChris Mason if (ret) 6143063d29fSChris Mason goto fail; 6153063d29fSChris Mason 6163063d29fSChris Mason /* 6173063d29fSChris Mason * insert the directory item 6183063d29fSChris Mason */ 6193063d29fSChris Mason key.offset = (u64)-1; 6203b96362cSSven Wegener namelen = strlen(pending->name); 6213063d29fSChris Mason ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root, 6223b96362cSSven Wegener pending->name, namelen, 6233063d29fSChris Mason root->fs_info->sb->s_root->d_inode->i_ino, 624aec7477bSJosef Bacik &key, BTRFS_FT_DIR, 0); 6253063d29fSChris Mason 6263063d29fSChris Mason if (ret) 6273063d29fSChris Mason goto fail; 6283063d29fSChris Mason 6293063d29fSChris Mason ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root, 6303063d29fSChris Mason pending->name, strlen(pending->name), objectid, 631aec7477bSJosef Bacik root->fs_info->sb->s_root->d_inode->i_ino, 0); 6323b96362cSSven Wegener 6333b96362cSSven Wegener /* Invalidate existing dcache entry for new snapshot. */ 6343b96362cSSven Wegener btrfs_invalidate_dcache_root(root, pending->name, namelen); 6353b96362cSSven Wegener 6363063d29fSChris Mason fail: 63780b6794dSChris Mason kfree(new_root_item); 6383063d29fSChris Mason return ret; 6393063d29fSChris Mason } 6403063d29fSChris Mason 64180b6794dSChris Mason static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans, 6423063d29fSChris Mason struct btrfs_fs_info *fs_info) 6433063d29fSChris Mason { 6443063d29fSChris Mason struct btrfs_pending_snapshot *pending; 6453063d29fSChris Mason struct list_head *head = &trans->transaction->pending_snapshots; 6463063d29fSChris Mason int ret; 6473063d29fSChris Mason 6483063d29fSChris Mason while(!list_empty(head)) { 6493063d29fSChris Mason pending = list_entry(head->next, 6503063d29fSChris Mason struct btrfs_pending_snapshot, list); 6513063d29fSChris Mason ret = create_pending_snapshot(trans, fs_info, pending); 6523063d29fSChris Mason BUG_ON(ret); 6533063d29fSChris Mason list_del(&pending->list); 6543063d29fSChris Mason kfree(pending->name); 6553063d29fSChris Mason kfree(pending); 6563063d29fSChris Mason } 657dc17ff8fSChris Mason return 0; 658dc17ff8fSChris Mason } 659dc17ff8fSChris Mason 66079154b1bSChris Mason int btrfs_commit_transaction(struct btrfs_trans_handle *trans, 66179154b1bSChris Mason struct btrfs_root *root) 66279154b1bSChris Mason { 66315ee9bc7SJosef Bacik unsigned long joined = 0; 66415ee9bc7SJosef Bacik unsigned long timeout = 1; 66579154b1bSChris Mason struct btrfs_transaction *cur_trans; 6668fd17795SChris Mason struct btrfs_transaction *prev_trans = NULL; 6670b86a832SChris Mason struct btrfs_root *chunk_root = root->fs_info->chunk_root; 6680f7d52f4SChris Mason struct list_head dirty_fs_roots; 669d1310b2eSChris Mason struct extent_io_tree *pinned_copy; 67079154b1bSChris Mason DEFINE_WAIT(wait); 67115ee9bc7SJosef Bacik int ret; 67279154b1bSChris Mason 6730f7d52f4SChris Mason INIT_LIST_HEAD(&dirty_fs_roots); 674d6e4a428SChris Mason 67579154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 67679154b1bSChris Mason if (trans->transaction->in_commit) { 67779154b1bSChris Mason cur_trans = trans->transaction; 67879154b1bSChris Mason trans->transaction->use_count++; 679ccd467d6SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 68079154b1bSChris Mason btrfs_end_transaction(trans, root); 681ccd467d6SChris Mason 68279154b1bSChris Mason ret = wait_for_commit(root, cur_trans); 68379154b1bSChris Mason BUG_ON(ret); 68415ee9bc7SJosef Bacik 68515ee9bc7SJosef Bacik mutex_lock(&root->fs_info->trans_mutex); 68679154b1bSChris Mason put_transaction(cur_trans); 68715ee9bc7SJosef Bacik mutex_unlock(&root->fs_info->trans_mutex); 68815ee9bc7SJosef Bacik 68979154b1bSChris Mason return 0; 69079154b1bSChris Mason } 6914313b399SChris Mason 6924313b399SChris Mason pinned_copy = kmalloc(sizeof(*pinned_copy), GFP_NOFS); 6934313b399SChris Mason if (!pinned_copy) 6944313b399SChris Mason return -ENOMEM; 6954313b399SChris Mason 696d1310b2eSChris Mason extent_io_tree_init(pinned_copy, 6974313b399SChris Mason root->fs_info->btree_inode->i_mapping, GFP_NOFS); 6984313b399SChris Mason 6992c90e5d6SChris Mason trans->transaction->in_commit = 1; 700f9295749SChris Mason trans->transaction->blocked = 1; 701ccd467d6SChris Mason cur_trans = trans->transaction; 702ccd467d6SChris Mason if (cur_trans->list.prev != &root->fs_info->trans_list) { 703ccd467d6SChris Mason prev_trans = list_entry(cur_trans->list.prev, 704ccd467d6SChris Mason struct btrfs_transaction, list); 705ccd467d6SChris Mason if (!prev_trans->commit_done) { 706ccd467d6SChris Mason prev_trans->use_count++; 707ccd467d6SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 708ccd467d6SChris Mason 709ccd467d6SChris Mason wait_for_commit(root, prev_trans); 710ccd467d6SChris Mason 711ccd467d6SChris Mason mutex_lock(&root->fs_info->trans_mutex); 71215ee9bc7SJosef Bacik put_transaction(prev_trans); 713ccd467d6SChris Mason } 714ccd467d6SChris Mason } 71515ee9bc7SJosef Bacik 71615ee9bc7SJosef Bacik do { 71715ee9bc7SJosef Bacik joined = cur_trans->num_joined; 7182c90e5d6SChris Mason WARN_ON(cur_trans != trans->transaction); 71915ee9bc7SJosef Bacik prepare_to_wait(&cur_trans->writer_wait, &wait, 72079154b1bSChris Mason TASK_UNINTERRUPTIBLE); 72115ee9bc7SJosef Bacik 72215ee9bc7SJosef Bacik if (cur_trans->num_writers > 1) 72315ee9bc7SJosef Bacik timeout = MAX_SCHEDULE_TIMEOUT; 72415ee9bc7SJosef Bacik else 72515ee9bc7SJosef Bacik timeout = 1; 72615ee9bc7SJosef Bacik 72779154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 72815ee9bc7SJosef Bacik 72915ee9bc7SJosef Bacik schedule_timeout(timeout); 73015ee9bc7SJosef Bacik 73179154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 73215ee9bc7SJosef Bacik finish_wait(&cur_trans->writer_wait, &wait); 73315ee9bc7SJosef Bacik } while (cur_trans->num_writers > 1 || 73415ee9bc7SJosef Bacik (cur_trans->num_joined != joined)); 73515ee9bc7SJosef Bacik 7363063d29fSChris Mason ret = create_pending_snapshots(trans, root->fs_info); 7373063d29fSChris Mason BUG_ON(ret); 7383063d29fSChris Mason 7392c90e5d6SChris Mason WARN_ON(cur_trans != trans->transaction); 740dc17ff8fSChris Mason 74154aa1f4dSChris Mason ret = add_dirty_roots(trans, &root->fs_info->fs_roots_radix, 74254aa1f4dSChris Mason &dirty_fs_roots); 74354aa1f4dSChris Mason BUG_ON(ret); 74454aa1f4dSChris Mason 74579154b1bSChris Mason ret = btrfs_commit_tree_roots(trans, root); 74679154b1bSChris Mason BUG_ON(ret); 74754aa1f4dSChris Mason 74878fae27eSChris Mason cur_trans = root->fs_info->running_transaction; 749cee36a03SChris Mason spin_lock(&root->fs_info->new_trans_lock); 75078fae27eSChris Mason root->fs_info->running_transaction = NULL; 751cee36a03SChris Mason spin_unlock(&root->fs_info->new_trans_lock); 7524b52dff6SChris Mason btrfs_set_super_generation(&root->fs_info->super_copy, 7534b52dff6SChris Mason cur_trans->transid); 7544b52dff6SChris Mason btrfs_set_super_root(&root->fs_info->super_copy, 755db94535dSChris Mason root->fs_info->tree_root->node->start); 756db94535dSChris Mason btrfs_set_super_root_level(&root->fs_info->super_copy, 757db94535dSChris Mason btrfs_header_level(root->fs_info->tree_root->node)); 7585f39d397SChris Mason 7590b86a832SChris Mason btrfs_set_super_chunk_root(&root->fs_info->super_copy, 7600b86a832SChris Mason chunk_root->node->start); 7610b86a832SChris Mason btrfs_set_super_chunk_root_level(&root->fs_info->super_copy, 7620b86a832SChris Mason btrfs_header_level(chunk_root->node)); 763a061fc8dSChris Mason memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy, 7644b52dff6SChris Mason sizeof(root->fs_info->super_copy)); 765ccd467d6SChris Mason 7664313b399SChris Mason btrfs_copy_pinned(root, pinned_copy); 767ccd467d6SChris Mason 768f9295749SChris Mason trans->transaction->blocked = 0; 769e6dcd2dcSChris Mason wake_up(&root->fs_info->transaction_throttle); 770f9295749SChris Mason wake_up(&root->fs_info->transaction_wait); 771e6dcd2dcSChris Mason 77278fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 77379154b1bSChris Mason ret = btrfs_write_and_wait_transaction(trans, root); 77479154b1bSChris Mason BUG_ON(ret); 77579154b1bSChris Mason write_ctree_super(trans, root); 7764313b399SChris Mason 7774313b399SChris Mason btrfs_finish_extent_commit(trans, root, pinned_copy); 77878fae27eSChris Mason mutex_lock(&root->fs_info->trans_mutex); 7794313b399SChris Mason 7804313b399SChris Mason kfree(pinned_copy); 7814313b399SChris Mason 7822c90e5d6SChris Mason cur_trans->commit_done = 1; 78315ee9bc7SJosef Bacik root->fs_info->last_trans_committed = cur_trans->transid; 7842c90e5d6SChris Mason wake_up(&cur_trans->commit_wait); 78579154b1bSChris Mason put_transaction(cur_trans); 78678fae27eSChris Mason put_transaction(cur_trans); 78758176a96SJosef Bacik 788facda1e7SChris Mason if (root->fs_info->closing) 789facda1e7SChris Mason list_splice_init(&root->fs_info->dead_roots, &dirty_fs_roots); 790facda1e7SChris Mason else 791facda1e7SChris Mason list_splice_init(&dirty_fs_roots, &root->fs_info->dead_roots); 79258176a96SJosef Bacik 79378fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 7942c90e5d6SChris Mason kmem_cache_free(btrfs_trans_handle_cachep, trans); 79579154b1bSChris Mason 796facda1e7SChris Mason if (root->fs_info->closing) { 7970f7d52f4SChris Mason drop_dirty_roots(root->fs_info->tree_root, &dirty_fs_roots); 798facda1e7SChris Mason } 79979154b1bSChris Mason return ret; 80079154b1bSChris Mason } 80179154b1bSChris Mason 802e9d0b13bSChris Mason int btrfs_clean_old_snapshots(struct btrfs_root *root) 803e9d0b13bSChris Mason { 804e9d0b13bSChris Mason struct list_head dirty_roots; 805e9d0b13bSChris Mason INIT_LIST_HEAD(&dirty_roots); 806a74a4b97SChris Mason again: 807e9d0b13bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 808e9d0b13bSChris Mason list_splice_init(&root->fs_info->dead_roots, &dirty_roots); 809e9d0b13bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 810e9d0b13bSChris Mason 811e9d0b13bSChris Mason if (!list_empty(&dirty_roots)) { 812e9d0b13bSChris Mason drop_dirty_roots(root, &dirty_roots); 813a74a4b97SChris Mason goto again; 814e9d0b13bSChris Mason } 815e9d0b13bSChris Mason return 0; 816e9d0b13bSChris Mason } 81708607c1bSChris Mason 818