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" 2779154b1bSChris Mason 2878fae27eSChris Mason static int total_trans = 0; 292c90e5d6SChris Mason extern struct kmem_cache *btrfs_trans_handle_cachep; 302c90e5d6SChris Mason extern struct kmem_cache *btrfs_transaction_cachep; 312c90e5d6SChris Mason 320f7d52f4SChris Mason #define BTRFS_ROOT_TRANS_TAG 0 330f7d52f4SChris Mason 3480b6794dSChris Mason static noinline void put_transaction(struct btrfs_transaction *transaction) 3579154b1bSChris Mason { 362c90e5d6SChris Mason WARN_ON(transaction->use_count == 0); 3779154b1bSChris Mason transaction->use_count--; 3878fae27eSChris Mason if (transaction->use_count == 0) { 3978fae27eSChris Mason WARN_ON(total_trans == 0); 4078fae27eSChris Mason total_trans--; 418fd17795SChris Mason list_del_init(&transaction->list); 422c90e5d6SChris Mason memset(transaction, 0, sizeof(*transaction)); 432c90e5d6SChris Mason kmem_cache_free(btrfs_transaction_cachep, transaction); 4479154b1bSChris Mason } 4578fae27eSChris Mason } 4679154b1bSChris Mason 4780b6794dSChris Mason static noinline int join_transaction(struct btrfs_root *root) 4879154b1bSChris Mason { 4979154b1bSChris Mason struct btrfs_transaction *cur_trans; 5079154b1bSChris Mason cur_trans = root->fs_info->running_transaction; 5179154b1bSChris Mason if (!cur_trans) { 522c90e5d6SChris Mason cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, 532c90e5d6SChris Mason GFP_NOFS); 5478fae27eSChris Mason total_trans++; 5579154b1bSChris Mason BUG_ON(!cur_trans); 560f7d52f4SChris Mason root->fs_info->generation++; 57e18e4809SChris Mason root->fs_info->last_alloc = 0; 584529ba49SChris Mason root->fs_info->last_data_alloc = 0; 5915ee9bc7SJosef Bacik cur_trans->num_writers = 1; 6015ee9bc7SJosef Bacik cur_trans->num_joined = 0; 610f7d52f4SChris Mason cur_trans->transid = root->fs_info->generation; 6279154b1bSChris Mason init_waitqueue_head(&cur_trans->writer_wait); 6379154b1bSChris Mason init_waitqueue_head(&cur_trans->commit_wait); 6479154b1bSChris Mason cur_trans->in_commit = 0; 65f9295749SChris Mason cur_trans->blocked = 0; 66d5719762SChris Mason cur_trans->use_count = 1; 6779154b1bSChris Mason cur_trans->commit_done = 0; 6808607c1bSChris Mason cur_trans->start_time = get_seconds(); 693063d29fSChris Mason INIT_LIST_HEAD(&cur_trans->pending_snapshots); 708fd17795SChris Mason list_add_tail(&cur_trans->list, &root->fs_info->trans_list); 71d1310b2eSChris Mason extent_io_tree_init(&cur_trans->dirty_pages, 725f39d397SChris Mason root->fs_info->btree_inode->i_mapping, 735f39d397SChris Mason GFP_NOFS); 7448ec2cf8SChris Mason spin_lock(&root->fs_info->new_trans_lock); 7548ec2cf8SChris Mason root->fs_info->running_transaction = cur_trans; 7648ec2cf8SChris Mason spin_unlock(&root->fs_info->new_trans_lock); 7715ee9bc7SJosef Bacik } else { 7879154b1bSChris Mason cur_trans->num_writers++; 7915ee9bc7SJosef Bacik cur_trans->num_joined++; 8015ee9bc7SJosef Bacik } 8115ee9bc7SJosef Bacik 8279154b1bSChris Mason return 0; 8379154b1bSChris Mason } 8479154b1bSChris Mason 8580b6794dSChris Mason static noinline int record_root_in_trans(struct btrfs_root *root) 866702ed49SChris Mason { 876702ed49SChris Mason u64 running_trans_id = root->fs_info->running_transaction->transid; 886702ed49SChris Mason if (root->ref_cows && root->last_trans < running_trans_id) { 896702ed49SChris Mason WARN_ON(root == root->fs_info->extent_root); 906702ed49SChris Mason if (root->root_item.refs != 0) { 916702ed49SChris Mason radix_tree_tag_set(&root->fs_info->fs_roots_radix, 926702ed49SChris Mason (unsigned long)root->root_key.objectid, 936702ed49SChris Mason BTRFS_ROOT_TRANS_TAG); 94925baeddSChris Mason root->commit_root = btrfs_root_node(root); 956702ed49SChris Mason } else { 966702ed49SChris Mason WARN_ON(1); 976702ed49SChris Mason } 986702ed49SChris Mason root->last_trans = running_trans_id; 996702ed49SChris Mason } 1006702ed49SChris Mason return 0; 1016702ed49SChris Mason } 1026702ed49SChris Mason 103f9295749SChris Mason struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, 104f9295749SChris Mason int num_blocks, int join) 10579154b1bSChris Mason { 1062c90e5d6SChris Mason struct btrfs_trans_handle *h = 1072c90e5d6SChris Mason kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); 108f9295749SChris Mason struct btrfs_transaction *cur_trans; 10979154b1bSChris Mason int ret; 11079154b1bSChris Mason 11179154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 112f9295749SChris Mason cur_trans = root->fs_info->running_transaction; 113f9295749SChris Mason if (cur_trans && cur_trans->blocked && !join) { 114f9295749SChris Mason DEFINE_WAIT(wait); 115f9295749SChris Mason cur_trans->use_count++; 116f9295749SChris Mason while(1) { 117f9295749SChris Mason prepare_to_wait(&root->fs_info->transaction_wait, &wait, 118f9295749SChris Mason TASK_UNINTERRUPTIBLE); 119f9295749SChris Mason if (cur_trans->blocked) { 120f9295749SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 121f9295749SChris Mason schedule(); 122f9295749SChris Mason mutex_lock(&root->fs_info->trans_mutex); 123f9295749SChris Mason finish_wait(&root->fs_info->transaction_wait, 124f9295749SChris Mason &wait); 125f9295749SChris Mason } else { 126f9295749SChris Mason finish_wait(&root->fs_info->transaction_wait, 127f9295749SChris Mason &wait); 128f9295749SChris Mason break; 129f9295749SChris Mason } 130f9295749SChris Mason } 131f9295749SChris Mason put_transaction(cur_trans); 132f9295749SChris Mason } 13379154b1bSChris Mason ret = join_transaction(root); 13479154b1bSChris Mason BUG_ON(ret); 1350f7d52f4SChris Mason 1366702ed49SChris Mason record_root_in_trans(root); 1376702ed49SChris Mason h->transid = root->fs_info->running_transaction->transid; 13879154b1bSChris Mason h->transaction = root->fs_info->running_transaction; 13979154b1bSChris Mason h->blocks_reserved = num_blocks; 14079154b1bSChris Mason h->blocks_used = 0; 14131f3c99bSChris Mason h->block_group = NULL; 14226b8003fSChris Mason h->alloc_exclude_nr = 0; 14326b8003fSChris Mason h->alloc_exclude_start = 0; 14479154b1bSChris Mason root->fs_info->running_transaction->use_count++; 14579154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 14679154b1bSChris Mason return h; 14779154b1bSChris Mason } 14879154b1bSChris Mason 149f9295749SChris Mason struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 150f9295749SChris Mason int num_blocks) 151f9295749SChris Mason { 152f9295749SChris Mason return start_transaction(root, num_blocks, 0); 153f9295749SChris Mason } 154f9295749SChris Mason struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, 155f9295749SChris Mason int num_blocks) 156f9295749SChris Mason { 157f9295749SChris Mason return start_transaction(root, num_blocks, 1); 158f9295749SChris Mason } 159f9295749SChris Mason 16089ce8a63SChris Mason static noinline int wait_for_commit(struct btrfs_root *root, 16189ce8a63SChris Mason struct btrfs_transaction *commit) 16289ce8a63SChris Mason { 16389ce8a63SChris Mason DEFINE_WAIT(wait); 16489ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 16589ce8a63SChris Mason while(!commit->commit_done) { 16689ce8a63SChris Mason prepare_to_wait(&commit->commit_wait, &wait, 16789ce8a63SChris Mason TASK_UNINTERRUPTIBLE); 16889ce8a63SChris Mason if (commit->commit_done) 16989ce8a63SChris Mason break; 17089ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 17189ce8a63SChris Mason schedule(); 17289ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 17389ce8a63SChris Mason } 17489ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 17589ce8a63SChris Mason finish_wait(&commit->commit_wait, &wait); 17689ce8a63SChris Mason return 0; 17789ce8a63SChris Mason } 17889ce8a63SChris Mason 17989ce8a63SChris Mason static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, 18089ce8a63SChris Mason struct btrfs_root *root, int throttle) 18179154b1bSChris Mason { 18279154b1bSChris Mason struct btrfs_transaction *cur_trans; 183d6e4a428SChris Mason 18479154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 18579154b1bSChris Mason cur_trans = root->fs_info->running_transaction; 186ccd467d6SChris Mason WARN_ON(cur_trans != trans->transaction); 187d5719762SChris Mason WARN_ON(cur_trans->num_writers < 1); 188ccd467d6SChris Mason cur_trans->num_writers--; 18989ce8a63SChris Mason 19079154b1bSChris Mason if (waitqueue_active(&cur_trans->writer_wait)) 19179154b1bSChris Mason wake_up(&cur_trans->writer_wait); 19289ce8a63SChris Mason 193f9295749SChris Mason if (0 && cur_trans->in_commit && throttle) { 194e6dcd2dcSChris Mason DEFINE_WAIT(wait); 19589ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 196e6dcd2dcSChris Mason prepare_to_wait(&root->fs_info->transaction_throttle, &wait, 197e6dcd2dcSChris Mason TASK_UNINTERRUPTIBLE); 198e6dcd2dcSChris Mason schedule(); 199e6dcd2dcSChris Mason finish_wait(&root->fs_info->transaction_throttle, &wait); 20089ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 20189ce8a63SChris Mason } 20289ce8a63SChris Mason 20379154b1bSChris Mason put_transaction(cur_trans); 20479154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 205d6025579SChris Mason memset(trans, 0, sizeof(*trans)); 2062c90e5d6SChris Mason kmem_cache_free(btrfs_trans_handle_cachep, trans); 20779154b1bSChris Mason return 0; 20879154b1bSChris Mason } 20979154b1bSChris Mason 21089ce8a63SChris Mason int btrfs_end_transaction(struct btrfs_trans_handle *trans, 21189ce8a63SChris Mason struct btrfs_root *root) 21289ce8a63SChris Mason { 21389ce8a63SChris Mason return __btrfs_end_transaction(trans, root, 0); 21489ce8a63SChris Mason } 21589ce8a63SChris Mason 21689ce8a63SChris Mason int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, 21789ce8a63SChris Mason struct btrfs_root *root) 21889ce8a63SChris Mason { 21989ce8a63SChris Mason return __btrfs_end_transaction(trans, root, 1); 22089ce8a63SChris Mason } 22189ce8a63SChris Mason 22279154b1bSChris Mason 22379154b1bSChris Mason int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, 22479154b1bSChris Mason struct btrfs_root *root) 22579154b1bSChris Mason { 2267c4452b9SChris Mason int ret; 2277c4452b9SChris Mason int err; 2287c4452b9SChris Mason int werr = 0; 229d1310b2eSChris Mason struct extent_io_tree *dirty_pages; 2307c4452b9SChris Mason struct page *page; 2317c4452b9SChris Mason struct inode *btree_inode = root->fs_info->btree_inode; 2325f39d397SChris Mason u64 start; 2335f39d397SChris Mason u64 end; 2345f39d397SChris Mason unsigned long index; 2357c4452b9SChris Mason 2367c4452b9SChris Mason if (!trans || !trans->transaction) { 2377c4452b9SChris Mason return filemap_write_and_wait(btree_inode->i_mapping); 2387c4452b9SChris Mason } 2397c4452b9SChris Mason dirty_pages = &trans->transaction->dirty_pages; 2407c4452b9SChris Mason while(1) { 2415f39d397SChris Mason ret = find_first_extent_bit(dirty_pages, 0, &start, &end, 2425f39d397SChris Mason EXTENT_DIRTY); 2435f39d397SChris Mason if (ret) 2447c4452b9SChris Mason break; 2455f39d397SChris Mason clear_extent_dirty(dirty_pages, start, end, GFP_NOFS); 2465f39d397SChris Mason while(start <= end) { 2475f39d397SChris Mason index = start >> PAGE_CACHE_SHIFT; 24835ebb934SChris Mason start = (u64)(index + 1) << PAGE_CACHE_SHIFT; 2495f39d397SChris Mason page = find_lock_page(btree_inode->i_mapping, index); 2507c4452b9SChris Mason if (!page) 2517c4452b9SChris Mason continue; 2526702ed49SChris Mason if (PageWriteback(page)) { 2536702ed49SChris Mason if (PageDirty(page)) 2546702ed49SChris Mason wait_on_page_writeback(page); 2556702ed49SChris Mason else { 2566702ed49SChris Mason unlock_page(page); 2576702ed49SChris Mason page_cache_release(page); 2586702ed49SChris Mason continue; 2596702ed49SChris Mason } 2606702ed49SChris Mason } 2617c4452b9SChris Mason err = write_one_page(page, 0); 2627c4452b9SChris Mason if (err) 2637c4452b9SChris Mason werr = err; 2647c4452b9SChris Mason page_cache_release(page); 2657c4452b9SChris Mason } 2667c4452b9SChris Mason } 2677c4452b9SChris Mason err = filemap_fdatawait(btree_inode->i_mapping); 2687c4452b9SChris Mason if (err) 2697c4452b9SChris Mason werr = err; 2707c4452b9SChris Mason return werr; 27179154b1bSChris Mason } 27279154b1bSChris Mason 2730b86a832SChris Mason static int update_cowonly_root(struct btrfs_trans_handle *trans, 27479154b1bSChris Mason struct btrfs_root *root) 27579154b1bSChris Mason { 27679154b1bSChris Mason int ret; 2770b86a832SChris Mason u64 old_root_bytenr; 2780b86a832SChris Mason struct btrfs_root *tree_root = root->fs_info->tree_root; 27979154b1bSChris Mason 2800b86a832SChris Mason btrfs_write_dirty_block_groups(trans, root); 28179154b1bSChris Mason while(1) { 2820b86a832SChris Mason old_root_bytenr = btrfs_root_bytenr(&root->root_item); 2830b86a832SChris Mason if (old_root_bytenr == root->node->start) 28479154b1bSChris Mason break; 2850b86a832SChris Mason btrfs_set_root_bytenr(&root->root_item, 2860b86a832SChris Mason root->node->start); 2870b86a832SChris Mason btrfs_set_root_level(&root->root_item, 2880b86a832SChris Mason btrfs_header_level(root->node)); 28979154b1bSChris Mason ret = btrfs_update_root(trans, tree_root, 2900b86a832SChris Mason &root->root_key, 2910b86a832SChris Mason &root->root_item); 29279154b1bSChris Mason BUG_ON(ret); 2930b86a832SChris Mason btrfs_write_dirty_block_groups(trans, root); 2940b86a832SChris Mason } 2950b86a832SChris Mason return 0; 2960b86a832SChris Mason } 2970b86a832SChris Mason 2980b86a832SChris Mason int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans, 2990b86a832SChris Mason struct btrfs_root *root) 3000b86a832SChris Mason { 3010b86a832SChris Mason struct btrfs_fs_info *fs_info = root->fs_info; 3020b86a832SChris Mason struct list_head *next; 3030b86a832SChris Mason 3040b86a832SChris Mason while(!list_empty(&fs_info->dirty_cowonly_roots)) { 3050b86a832SChris Mason next = fs_info->dirty_cowonly_roots.next; 3060b86a832SChris Mason list_del_init(next); 3070b86a832SChris Mason root = list_entry(next, struct btrfs_root, dirty_list); 3080b86a832SChris Mason update_cowonly_root(trans, root); 30979154b1bSChris Mason } 31079154b1bSChris Mason return 0; 31179154b1bSChris Mason } 31279154b1bSChris Mason 3130f7d52f4SChris Mason struct dirty_root { 3140f7d52f4SChris Mason struct list_head list; 3150f7d52f4SChris Mason struct btrfs_root *root; 31658176a96SJosef Bacik struct btrfs_root *latest_root; 3170f7d52f4SChris Mason }; 3180f7d52f4SChris Mason 3195ce14bbcSChris Mason int btrfs_add_dead_root(struct btrfs_root *root, 3205ce14bbcSChris Mason struct btrfs_root *latest, 3215ce14bbcSChris Mason struct list_head *dead_list) 3225eda7b5eSChris Mason { 3235eda7b5eSChris Mason struct dirty_root *dirty; 3245eda7b5eSChris Mason 3255eda7b5eSChris Mason dirty = kmalloc(sizeof(*dirty), GFP_NOFS); 3265eda7b5eSChris Mason if (!dirty) 3275eda7b5eSChris Mason return -ENOMEM; 3285eda7b5eSChris Mason dirty->root = root; 3295ce14bbcSChris Mason dirty->latest_root = latest; 3305eda7b5eSChris Mason list_add(&dirty->list, dead_list); 3315eda7b5eSChris Mason return 0; 3325eda7b5eSChris Mason } 3335eda7b5eSChris Mason 33480b6794dSChris Mason static noinline int add_dirty_roots(struct btrfs_trans_handle *trans, 33535b7e476SChris Mason struct radix_tree_root *radix, 33635b7e476SChris Mason struct list_head *list) 3370f7d52f4SChris Mason { 3380f7d52f4SChris Mason struct dirty_root *dirty; 3390f7d52f4SChris Mason struct btrfs_root *gang[8]; 3400f7d52f4SChris Mason struct btrfs_root *root; 3410f7d52f4SChris Mason int i; 3420f7d52f4SChris Mason int ret; 34354aa1f4dSChris Mason int err = 0; 3445eda7b5eSChris Mason u32 refs; 34554aa1f4dSChris Mason 3460f7d52f4SChris Mason while(1) { 3470f7d52f4SChris Mason ret = radix_tree_gang_lookup_tag(radix, (void **)gang, 0, 3480f7d52f4SChris Mason ARRAY_SIZE(gang), 3490f7d52f4SChris Mason BTRFS_ROOT_TRANS_TAG); 3500f7d52f4SChris Mason if (ret == 0) 3510f7d52f4SChris Mason break; 3520f7d52f4SChris Mason for (i = 0; i < ret; i++) { 3530f7d52f4SChris Mason root = gang[i]; 3542619ba1fSChris Mason radix_tree_tag_clear(radix, 3552619ba1fSChris Mason (unsigned long)root->root_key.objectid, 3560f7d52f4SChris Mason BTRFS_ROOT_TRANS_TAG); 3570f7d52f4SChris Mason if (root->commit_root == root->node) { 358db94535dSChris Mason WARN_ON(root->node->start != 359db94535dSChris Mason btrfs_root_bytenr(&root->root_item)); 3605f39d397SChris Mason free_extent_buffer(root->commit_root); 3610f7d52f4SChris Mason root->commit_root = NULL; 36258176a96SJosef Bacik 36358176a96SJosef Bacik /* make sure to update the root on disk 36458176a96SJosef Bacik * so we get any updates to the block used 36558176a96SJosef Bacik * counts 36658176a96SJosef Bacik */ 36758176a96SJosef Bacik err = btrfs_update_root(trans, 36858176a96SJosef Bacik root->fs_info->tree_root, 36958176a96SJosef Bacik &root->root_key, 37058176a96SJosef Bacik &root->root_item); 3710f7d52f4SChris Mason continue; 3720f7d52f4SChris Mason } 3730f7d52f4SChris Mason dirty = kmalloc(sizeof(*dirty), GFP_NOFS); 3740f7d52f4SChris Mason BUG_ON(!dirty); 3759f3a7427SChris Mason dirty->root = kmalloc(sizeof(*dirty->root), GFP_NOFS); 3769f3a7427SChris Mason BUG_ON(!dirty->root); 3779f3a7427SChris Mason 3789f3a7427SChris Mason memset(&root->root_item.drop_progress, 0, 3799f3a7427SChris Mason sizeof(struct btrfs_disk_key)); 3809f3a7427SChris Mason root->root_item.drop_level = 0; 3819f3a7427SChris Mason 3829f3a7427SChris Mason memcpy(dirty->root, root, sizeof(*root)); 3839f3a7427SChris Mason dirty->root->node = root->commit_root; 38458176a96SJosef Bacik dirty->latest_root = root; 385ed98b56aSChris Mason spin_lock_init(&dirty->root->node_lock); 386ed98b56aSChris Mason mutex_init(&dirty->root->objectid_mutex); 387ed98b56aSChris Mason 3880f7d52f4SChris Mason root->commit_root = NULL; 3895eda7b5eSChris Mason 3900f7d52f4SChris Mason root->root_key.offset = root->fs_info->generation; 391db94535dSChris Mason btrfs_set_root_bytenr(&root->root_item, 392db94535dSChris Mason root->node->start); 393db94535dSChris Mason btrfs_set_root_level(&root->root_item, 394db94535dSChris Mason btrfs_header_level(root->node)); 3950f7d52f4SChris Mason err = btrfs_insert_root(trans, root->fs_info->tree_root, 3960f7d52f4SChris Mason &root->root_key, 3970f7d52f4SChris Mason &root->root_item); 39854aa1f4dSChris Mason if (err) 39954aa1f4dSChris Mason break; 4009f3a7427SChris Mason 4019f3a7427SChris Mason refs = btrfs_root_refs(&dirty->root->root_item); 4029f3a7427SChris Mason btrfs_set_root_refs(&dirty->root->root_item, refs - 1); 4035eda7b5eSChris Mason err = btrfs_update_root(trans, root->fs_info->tree_root, 4049f3a7427SChris Mason &dirty->root->root_key, 4059f3a7427SChris Mason &dirty->root->root_item); 4065eda7b5eSChris Mason 4075eda7b5eSChris Mason BUG_ON(err); 4089f3a7427SChris Mason if (refs == 1) { 4090f7d52f4SChris Mason list_add(&dirty->list, list); 4109f3a7427SChris Mason } else { 4119f3a7427SChris Mason WARN_ON(1); 4129f3a7427SChris Mason kfree(dirty->root); 4135eda7b5eSChris Mason kfree(dirty); 4140f7d52f4SChris Mason } 4150f7d52f4SChris Mason } 4169f3a7427SChris Mason } 41754aa1f4dSChris Mason return err; 4180f7d52f4SChris Mason } 4190f7d52f4SChris Mason 420e9d0b13bSChris Mason int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) 421e9d0b13bSChris Mason { 422e9d0b13bSChris Mason struct btrfs_fs_info *info = root->fs_info; 423e9d0b13bSChris Mason int ret; 424e9d0b13bSChris Mason struct btrfs_trans_handle *trans; 425d3c2fdcfSChris Mason unsigned long nr; 426e9d0b13bSChris Mason 427a2135011SChris Mason smp_mb(); 428e9d0b13bSChris Mason if (root->defrag_running) 429e9d0b13bSChris Mason return 0; 430e9d0b13bSChris Mason trans = btrfs_start_transaction(root, 1); 4316b80053dSChris Mason while (1) { 432e9d0b13bSChris Mason root->defrag_running = 1; 433e9d0b13bSChris Mason ret = btrfs_defrag_leaves(trans, root, cacheonly); 434d3c2fdcfSChris Mason nr = trans->blocks_used; 435e9d0b13bSChris Mason btrfs_end_transaction(trans, root); 436d3c2fdcfSChris Mason btrfs_btree_balance_dirty(info->tree_root, nr); 437e9d0b13bSChris Mason cond_resched(); 438e9d0b13bSChris Mason 439e9d0b13bSChris Mason trans = btrfs_start_transaction(root, 1); 4403f157a2fSChris Mason if (root->fs_info->closing || ret != -EAGAIN) 441e9d0b13bSChris Mason break; 442e9d0b13bSChris Mason } 443e9d0b13bSChris Mason root->defrag_running = 0; 444a2135011SChris Mason smp_mb(); 445e9d0b13bSChris Mason btrfs_end_transaction(trans, root); 446e9d0b13bSChris Mason return 0; 447e9d0b13bSChris Mason } 448e9d0b13bSChris Mason 44980b6794dSChris Mason static noinline int drop_dirty_roots(struct btrfs_root *tree_root, 45035b7e476SChris Mason struct list_head *list) 4510f7d52f4SChris Mason { 4520f7d52f4SChris Mason struct dirty_root *dirty; 4530f7d52f4SChris Mason struct btrfs_trans_handle *trans; 454d3c2fdcfSChris Mason unsigned long nr; 455db94535dSChris Mason u64 num_bytes; 456db94535dSChris Mason u64 bytes_used; 45754aa1f4dSChris Mason int ret = 0; 4589f3a7427SChris Mason int err; 4599f3a7427SChris Mason 4600f7d52f4SChris Mason while(!list_empty(list)) { 46158176a96SJosef Bacik struct btrfs_root *root; 46258176a96SJosef Bacik 4630f7d52f4SChris Mason dirty = list_entry(list->next, struct dirty_root, list); 4640f7d52f4SChris Mason list_del_init(&dirty->list); 4655eda7b5eSChris Mason 466db94535dSChris Mason num_bytes = btrfs_root_used(&dirty->root->root_item); 46758176a96SJosef Bacik root = dirty->latest_root; 468a2135011SChris Mason atomic_inc(&root->fs_info->throttles); 46958176a96SJosef Bacik 470a2135011SChris Mason mutex_lock(&root->fs_info->drop_mutex); 4719f3a7427SChris Mason while(1) { 4720f7d52f4SChris Mason trans = btrfs_start_transaction(tree_root, 1); 4739f3a7427SChris Mason ret = btrfs_drop_snapshot(trans, dirty->root); 4749f3a7427SChris Mason if (ret != -EAGAIN) { 4759f3a7427SChris Mason break; 4769f3a7427SChris Mason } 47758176a96SJosef Bacik 4789f3a7427SChris Mason err = btrfs_update_root(trans, 4799f3a7427SChris Mason tree_root, 4809f3a7427SChris Mason &dirty->root->root_key, 4819f3a7427SChris Mason &dirty->root->root_item); 4829f3a7427SChris Mason if (err) 4839f3a7427SChris Mason ret = err; 484d3c2fdcfSChris Mason nr = trans->blocks_used; 4851b1e2135SChris Mason ret = btrfs_end_transaction_throttle(trans, tree_root); 4860f7d52f4SChris Mason BUG_ON(ret); 487a2135011SChris Mason 488a2135011SChris Mason mutex_unlock(&root->fs_info->drop_mutex); 489d3c2fdcfSChris Mason btrfs_btree_balance_dirty(tree_root, nr); 4904dc11904SChris Mason cond_resched(); 491a2135011SChris Mason mutex_lock(&root->fs_info->drop_mutex); 4929f3a7427SChris Mason } 4939f3a7427SChris Mason BUG_ON(ret); 494a2135011SChris Mason atomic_dec(&root->fs_info->throttles); 49558176a96SJosef Bacik 496a2135011SChris Mason mutex_lock(&root->fs_info->alloc_mutex); 497db94535dSChris Mason num_bytes -= btrfs_root_used(&dirty->root->root_item); 498db94535dSChris Mason bytes_used = btrfs_root_used(&root->root_item); 499db94535dSChris Mason if (num_bytes) { 50058176a96SJosef Bacik record_root_in_trans(root); 5015f39d397SChris Mason btrfs_set_root_used(&root->root_item, 502db94535dSChris Mason bytes_used - num_bytes); 50358176a96SJosef Bacik } 504a2135011SChris Mason mutex_unlock(&root->fs_info->alloc_mutex); 505a2135011SChris Mason 5069f3a7427SChris Mason ret = btrfs_del_root(trans, tree_root, &dirty->root->root_key); 50758176a96SJosef Bacik if (ret) { 50858176a96SJosef Bacik BUG(); 50954aa1f4dSChris Mason break; 51058176a96SJosef Bacik } 511a2135011SChris Mason mutex_unlock(&root->fs_info->drop_mutex); 512a2135011SChris Mason 513d3c2fdcfSChris Mason nr = trans->blocks_used; 5140f7d52f4SChris Mason ret = btrfs_end_transaction(trans, tree_root); 5150f7d52f4SChris Mason BUG_ON(ret); 5165eda7b5eSChris Mason 517f510cfecSChris Mason free_extent_buffer(dirty->root->node); 5185eda7b5eSChris Mason kfree(dirty->root); 5190f7d52f4SChris Mason kfree(dirty); 520d3c2fdcfSChris Mason 521d3c2fdcfSChris Mason btrfs_btree_balance_dirty(tree_root, nr); 5224dc11904SChris Mason cond_resched(); 5230f7d52f4SChris Mason } 52454aa1f4dSChris Mason return ret; 5250f7d52f4SChris Mason } 5260f7d52f4SChris Mason 52780b6794dSChris Mason static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, 5283063d29fSChris Mason struct btrfs_fs_info *fs_info, 5293063d29fSChris Mason struct btrfs_pending_snapshot *pending) 5303063d29fSChris Mason { 5313063d29fSChris Mason struct btrfs_key key; 53280b6794dSChris Mason struct btrfs_root_item *new_root_item; 5333063d29fSChris Mason struct btrfs_root *tree_root = fs_info->tree_root; 5343063d29fSChris Mason struct btrfs_root *root = pending->root; 5353063d29fSChris Mason struct extent_buffer *tmp; 536925baeddSChris Mason struct extent_buffer *old; 5373063d29fSChris Mason int ret; 5383b96362cSSven Wegener int namelen; 5393063d29fSChris Mason u64 objectid; 5403063d29fSChris Mason 54180b6794dSChris Mason new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); 54280b6794dSChris Mason if (!new_root_item) { 54380b6794dSChris Mason ret = -ENOMEM; 54480b6794dSChris Mason goto fail; 54580b6794dSChris Mason } 5463063d29fSChris Mason ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); 5473063d29fSChris Mason if (ret) 5483063d29fSChris Mason goto fail; 5493063d29fSChris Mason 55080b6794dSChris Mason memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); 5513063d29fSChris Mason 5523063d29fSChris Mason key.objectid = objectid; 5533063d29fSChris Mason key.offset = 1; 5543063d29fSChris Mason btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); 5553063d29fSChris Mason 556925baeddSChris Mason old = btrfs_lock_root_node(root); 557925baeddSChris Mason btrfs_cow_block(trans, root, old, NULL, 0, &old); 5583063d29fSChris Mason 559925baeddSChris Mason btrfs_copy_root(trans, root, old, &tmp, objectid); 560925baeddSChris Mason btrfs_tree_unlock(old); 561925baeddSChris Mason free_extent_buffer(old); 5623063d29fSChris Mason 56380b6794dSChris Mason btrfs_set_root_bytenr(new_root_item, tmp->start); 56480b6794dSChris Mason btrfs_set_root_level(new_root_item, btrfs_header_level(tmp)); 5653063d29fSChris Mason ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, 56680b6794dSChris Mason new_root_item); 567925baeddSChris Mason btrfs_tree_unlock(tmp); 5683063d29fSChris Mason free_extent_buffer(tmp); 5693063d29fSChris Mason if (ret) 5703063d29fSChris Mason goto fail; 5713063d29fSChris Mason 5723063d29fSChris Mason /* 5733063d29fSChris Mason * insert the directory item 5743063d29fSChris Mason */ 5753063d29fSChris Mason key.offset = (u64)-1; 5763b96362cSSven Wegener namelen = strlen(pending->name); 5773063d29fSChris Mason ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root, 5783b96362cSSven Wegener pending->name, namelen, 5793063d29fSChris Mason root->fs_info->sb->s_root->d_inode->i_ino, 5803063d29fSChris Mason &key, BTRFS_FT_DIR); 5813063d29fSChris Mason 5823063d29fSChris Mason if (ret) 5833063d29fSChris Mason goto fail; 5843063d29fSChris Mason 5853063d29fSChris Mason ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root, 5863063d29fSChris Mason pending->name, strlen(pending->name), objectid, 5873063d29fSChris Mason root->fs_info->sb->s_root->d_inode->i_ino); 5883b96362cSSven Wegener 5893b96362cSSven Wegener /* Invalidate existing dcache entry for new snapshot. */ 5903b96362cSSven Wegener btrfs_invalidate_dcache_root(root, pending->name, namelen); 5913b96362cSSven Wegener 5923063d29fSChris Mason fail: 59380b6794dSChris Mason kfree(new_root_item); 5943063d29fSChris Mason return ret; 5953063d29fSChris Mason } 5963063d29fSChris Mason 59780b6794dSChris Mason static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans, 5983063d29fSChris Mason struct btrfs_fs_info *fs_info) 5993063d29fSChris Mason { 6003063d29fSChris Mason struct btrfs_pending_snapshot *pending; 6013063d29fSChris Mason struct list_head *head = &trans->transaction->pending_snapshots; 6023063d29fSChris Mason int ret; 6033063d29fSChris Mason 6043063d29fSChris Mason while(!list_empty(head)) { 6053063d29fSChris Mason pending = list_entry(head->next, 6063063d29fSChris Mason struct btrfs_pending_snapshot, list); 6073063d29fSChris Mason ret = create_pending_snapshot(trans, fs_info, pending); 6083063d29fSChris Mason BUG_ON(ret); 6093063d29fSChris Mason list_del(&pending->list); 6103063d29fSChris Mason kfree(pending->name); 6113063d29fSChris Mason kfree(pending); 6123063d29fSChris Mason } 613dc17ff8fSChris Mason return 0; 614dc17ff8fSChris Mason } 615dc17ff8fSChris Mason 61679154b1bSChris Mason int btrfs_commit_transaction(struct btrfs_trans_handle *trans, 61779154b1bSChris Mason struct btrfs_root *root) 61879154b1bSChris Mason { 61915ee9bc7SJosef Bacik unsigned long joined = 0; 62015ee9bc7SJosef Bacik unsigned long timeout = 1; 62179154b1bSChris Mason struct btrfs_transaction *cur_trans; 6228fd17795SChris Mason struct btrfs_transaction *prev_trans = NULL; 6230b86a832SChris Mason struct btrfs_root *chunk_root = root->fs_info->chunk_root; 6240f7d52f4SChris Mason struct list_head dirty_fs_roots; 625d1310b2eSChris Mason struct extent_io_tree *pinned_copy; 62679154b1bSChris Mason DEFINE_WAIT(wait); 62715ee9bc7SJosef Bacik int ret; 62879154b1bSChris Mason 6290f7d52f4SChris Mason INIT_LIST_HEAD(&dirty_fs_roots); 630d6e4a428SChris Mason 63179154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 63279154b1bSChris Mason if (trans->transaction->in_commit) { 63379154b1bSChris Mason cur_trans = trans->transaction; 63479154b1bSChris Mason trans->transaction->use_count++; 635ccd467d6SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 63679154b1bSChris Mason btrfs_end_transaction(trans, root); 637ccd467d6SChris Mason 63879154b1bSChris Mason ret = wait_for_commit(root, cur_trans); 63979154b1bSChris Mason BUG_ON(ret); 64015ee9bc7SJosef Bacik 64115ee9bc7SJosef Bacik mutex_lock(&root->fs_info->trans_mutex); 64279154b1bSChris Mason put_transaction(cur_trans); 64315ee9bc7SJosef Bacik mutex_unlock(&root->fs_info->trans_mutex); 64415ee9bc7SJosef Bacik 64579154b1bSChris Mason return 0; 64679154b1bSChris Mason } 6474313b399SChris Mason 6484313b399SChris Mason pinned_copy = kmalloc(sizeof(*pinned_copy), GFP_NOFS); 6494313b399SChris Mason if (!pinned_copy) 6504313b399SChris Mason return -ENOMEM; 6514313b399SChris Mason 652d1310b2eSChris Mason extent_io_tree_init(pinned_copy, 6534313b399SChris Mason root->fs_info->btree_inode->i_mapping, GFP_NOFS); 6544313b399SChris Mason 6552c90e5d6SChris Mason trans->transaction->in_commit = 1; 656f9295749SChris Mason trans->transaction->blocked = 1; 657ccd467d6SChris Mason cur_trans = trans->transaction; 658ccd467d6SChris Mason if (cur_trans->list.prev != &root->fs_info->trans_list) { 659ccd467d6SChris Mason prev_trans = list_entry(cur_trans->list.prev, 660ccd467d6SChris Mason struct btrfs_transaction, list); 661ccd467d6SChris Mason if (!prev_trans->commit_done) { 662ccd467d6SChris Mason prev_trans->use_count++; 663ccd467d6SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 664ccd467d6SChris Mason 665ccd467d6SChris Mason wait_for_commit(root, prev_trans); 666ccd467d6SChris Mason 667ccd467d6SChris Mason mutex_lock(&root->fs_info->trans_mutex); 66815ee9bc7SJosef Bacik put_transaction(prev_trans); 669ccd467d6SChris Mason } 670ccd467d6SChris Mason } 67115ee9bc7SJosef Bacik 67215ee9bc7SJosef Bacik do { 67315ee9bc7SJosef Bacik joined = cur_trans->num_joined; 6742c90e5d6SChris Mason WARN_ON(cur_trans != trans->transaction); 67515ee9bc7SJosef Bacik prepare_to_wait(&cur_trans->writer_wait, &wait, 67679154b1bSChris Mason TASK_UNINTERRUPTIBLE); 67715ee9bc7SJosef Bacik 67815ee9bc7SJosef Bacik if (cur_trans->num_writers > 1) 67915ee9bc7SJosef Bacik timeout = MAX_SCHEDULE_TIMEOUT; 68015ee9bc7SJosef Bacik else 68115ee9bc7SJosef Bacik timeout = 1; 68215ee9bc7SJosef Bacik 68379154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 68415ee9bc7SJosef Bacik 68515ee9bc7SJosef Bacik schedule_timeout(timeout); 68615ee9bc7SJosef Bacik 68779154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 68815ee9bc7SJosef Bacik finish_wait(&cur_trans->writer_wait, &wait); 68915ee9bc7SJosef Bacik } while (cur_trans->num_writers > 1 || 69015ee9bc7SJosef Bacik (cur_trans->num_joined != joined)); 69115ee9bc7SJosef Bacik 6923063d29fSChris Mason ret = create_pending_snapshots(trans, root->fs_info); 6933063d29fSChris Mason BUG_ON(ret); 6943063d29fSChris Mason 6952c90e5d6SChris Mason WARN_ON(cur_trans != trans->transaction); 696dc17ff8fSChris Mason 69754aa1f4dSChris Mason ret = add_dirty_roots(trans, &root->fs_info->fs_roots_radix, 69854aa1f4dSChris Mason &dirty_fs_roots); 69954aa1f4dSChris Mason BUG_ON(ret); 70054aa1f4dSChris Mason 70179154b1bSChris Mason ret = btrfs_commit_tree_roots(trans, root); 70279154b1bSChris Mason BUG_ON(ret); 70354aa1f4dSChris Mason 70478fae27eSChris Mason cur_trans = root->fs_info->running_transaction; 705cee36a03SChris Mason spin_lock(&root->fs_info->new_trans_lock); 70678fae27eSChris Mason root->fs_info->running_transaction = NULL; 707cee36a03SChris Mason spin_unlock(&root->fs_info->new_trans_lock); 7084b52dff6SChris Mason btrfs_set_super_generation(&root->fs_info->super_copy, 7094b52dff6SChris Mason cur_trans->transid); 7104b52dff6SChris Mason btrfs_set_super_root(&root->fs_info->super_copy, 711db94535dSChris Mason root->fs_info->tree_root->node->start); 712db94535dSChris Mason btrfs_set_super_root_level(&root->fs_info->super_copy, 713db94535dSChris Mason btrfs_header_level(root->fs_info->tree_root->node)); 7145f39d397SChris Mason 7150b86a832SChris Mason btrfs_set_super_chunk_root(&root->fs_info->super_copy, 7160b86a832SChris Mason chunk_root->node->start); 7170b86a832SChris Mason btrfs_set_super_chunk_root_level(&root->fs_info->super_copy, 7180b86a832SChris Mason btrfs_header_level(chunk_root->node)); 719a061fc8dSChris Mason memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy, 7204b52dff6SChris Mason sizeof(root->fs_info->super_copy)); 721ccd467d6SChris Mason 7224313b399SChris Mason btrfs_copy_pinned(root, pinned_copy); 723ccd467d6SChris Mason 724f9295749SChris Mason trans->transaction->blocked = 0; 725e6dcd2dcSChris Mason wake_up(&root->fs_info->transaction_throttle); 726f9295749SChris Mason wake_up(&root->fs_info->transaction_wait); 727e6dcd2dcSChris Mason 72878fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 72979154b1bSChris Mason ret = btrfs_write_and_wait_transaction(trans, root); 73079154b1bSChris Mason BUG_ON(ret); 73179154b1bSChris Mason write_ctree_super(trans, root); 7324313b399SChris Mason 7334313b399SChris Mason btrfs_finish_extent_commit(trans, root, pinned_copy); 73478fae27eSChris Mason mutex_lock(&root->fs_info->trans_mutex); 7354313b399SChris Mason 7364313b399SChris Mason kfree(pinned_copy); 7374313b399SChris Mason 7382c90e5d6SChris Mason cur_trans->commit_done = 1; 73915ee9bc7SJosef Bacik root->fs_info->last_trans_committed = cur_trans->transid; 7402c90e5d6SChris Mason wake_up(&cur_trans->commit_wait); 74179154b1bSChris Mason put_transaction(cur_trans); 74278fae27eSChris Mason put_transaction(cur_trans); 74358176a96SJosef Bacik 744facda1e7SChris Mason if (root->fs_info->closing) 745facda1e7SChris Mason list_splice_init(&root->fs_info->dead_roots, &dirty_fs_roots); 746facda1e7SChris Mason else 747facda1e7SChris Mason list_splice_init(&dirty_fs_roots, &root->fs_info->dead_roots); 74858176a96SJosef Bacik 74978fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 7502c90e5d6SChris Mason kmem_cache_free(btrfs_trans_handle_cachep, trans); 75179154b1bSChris Mason 752facda1e7SChris Mason if (root->fs_info->closing) { 7530f7d52f4SChris Mason drop_dirty_roots(root->fs_info->tree_root, &dirty_fs_roots); 754facda1e7SChris Mason } 75579154b1bSChris Mason return ret; 75679154b1bSChris Mason } 75779154b1bSChris Mason 758e9d0b13bSChris Mason int btrfs_clean_old_snapshots(struct btrfs_root *root) 759e9d0b13bSChris Mason { 760e9d0b13bSChris Mason struct list_head dirty_roots; 761e9d0b13bSChris Mason INIT_LIST_HEAD(&dirty_roots); 762a74a4b97SChris Mason again: 763e9d0b13bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 764e9d0b13bSChris Mason list_splice_init(&root->fs_info->dead_roots, &dirty_roots); 765e9d0b13bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 766e9d0b13bSChris Mason 767e9d0b13bSChris Mason if (!list_empty(&dirty_roots)) { 768e9d0b13bSChris Mason drop_dirty_roots(root, &dirty_roots); 769a74a4b97SChris Mason goto again; 770e9d0b13bSChris Mason } 771e9d0b13bSChris Mason return 0; 772e9d0b13bSChris Mason } 77308607c1bSChris Mason 774