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> 205a0e3ad6STejun Heo #include <linux/slab.h> 2134088780SChris Mason #include <linux/sched.h> 22d3c2fdcfSChris Mason #include <linux/writeback.h> 235f39d397SChris Mason #include <linux/pagemap.h> 245f2cc086SChris Mason #include <linux/blkdev.h> 2579154b1bSChris Mason #include "ctree.h" 2679154b1bSChris Mason #include "disk-io.h" 2779154b1bSChris Mason #include "transaction.h" 28925baeddSChris Mason #include "locking.h" 29e02119d5SChris Mason #include "tree-log.h" 3079154b1bSChris Mason 310f7d52f4SChris Mason #define BTRFS_ROOT_TRANS_TAG 0 320f7d52f4SChris Mason 3380b6794dSChris Mason static noinline void put_transaction(struct btrfs_transaction *transaction) 3479154b1bSChris Mason { 3513c5a93eSJosef Bacik WARN_ON(atomic_read(&transaction->use_count) == 0); 3613c5a93eSJosef Bacik if (atomic_dec_and_test(&transaction->use_count)) { 372c90e5d6SChris Mason memset(transaction, 0, sizeof(*transaction)); 382c90e5d6SChris Mason kmem_cache_free(btrfs_transaction_cachep, transaction); 3979154b1bSChris Mason } 4078fae27eSChris Mason } 4179154b1bSChris Mason 42817d52f8SJosef Bacik static noinline void switch_commit_root(struct btrfs_root *root) 43817d52f8SJosef Bacik { 44817d52f8SJosef Bacik free_extent_buffer(root->commit_root); 45817d52f8SJosef Bacik root->commit_root = btrfs_root_node(root); 46817d52f8SJosef Bacik } 47817d52f8SJosef Bacik 48d352ac68SChris Mason /* 49d352ac68SChris Mason * either allocate a new transaction or hop into the existing one 50d352ac68SChris Mason */ 5180b6794dSChris Mason static noinline int join_transaction(struct btrfs_root *root) 5279154b1bSChris Mason { 5379154b1bSChris Mason struct btrfs_transaction *cur_trans; 5479154b1bSChris Mason cur_trans = root->fs_info->running_transaction; 5579154b1bSChris Mason if (!cur_trans) { 562c90e5d6SChris Mason cur_trans = kmem_cache_alloc(btrfs_transaction_cachep, 572c90e5d6SChris Mason GFP_NOFS); 58db5b493aSTsutomu Itoh if (!cur_trans) 59db5b493aSTsutomu Itoh return -ENOMEM; 600f7d52f4SChris Mason root->fs_info->generation++; 6113c5a93eSJosef Bacik atomic_set(&cur_trans->num_writers, 1); 6215ee9bc7SJosef Bacik cur_trans->num_joined = 0; 630f7d52f4SChris Mason cur_trans->transid = root->fs_info->generation; 6479154b1bSChris Mason init_waitqueue_head(&cur_trans->writer_wait); 6579154b1bSChris Mason init_waitqueue_head(&cur_trans->commit_wait); 6679154b1bSChris Mason cur_trans->in_commit = 0; 67f9295749SChris Mason cur_trans->blocked = 0; 6813c5a93eSJosef Bacik atomic_set(&cur_trans->use_count, 1); 6979154b1bSChris Mason cur_trans->commit_done = 0; 7008607c1bSChris Mason cur_trans->start_time = get_seconds(); 7156bec294SChris Mason 726bef4d31SEric Paris cur_trans->delayed_refs.root = RB_ROOT; 7356bec294SChris Mason cur_trans->delayed_refs.num_entries = 0; 74c3e69d58SChris Mason cur_trans->delayed_refs.num_heads_ready = 0; 75c3e69d58SChris Mason cur_trans->delayed_refs.num_heads = 0; 7656bec294SChris Mason cur_trans->delayed_refs.flushing = 0; 77c3e69d58SChris Mason cur_trans->delayed_refs.run_delayed_start = 0; 7856bec294SChris Mason spin_lock_init(&cur_trans->delayed_refs.lock); 7956bec294SChris Mason 803063d29fSChris Mason INIT_LIST_HEAD(&cur_trans->pending_snapshots); 818fd17795SChris Mason list_add_tail(&cur_trans->list, &root->fs_info->trans_list); 82d1310b2eSChris Mason extent_io_tree_init(&cur_trans->dirty_pages, 835f39d397SChris Mason root->fs_info->btree_inode->i_mapping, 845f39d397SChris Mason GFP_NOFS); 8548ec2cf8SChris Mason spin_lock(&root->fs_info->new_trans_lock); 8648ec2cf8SChris Mason root->fs_info->running_transaction = cur_trans; 8748ec2cf8SChris Mason spin_unlock(&root->fs_info->new_trans_lock); 8815ee9bc7SJosef Bacik } else { 8913c5a93eSJosef Bacik atomic_inc(&cur_trans->num_writers); 9015ee9bc7SJosef Bacik cur_trans->num_joined++; 9115ee9bc7SJosef Bacik } 9215ee9bc7SJosef Bacik 9379154b1bSChris Mason return 0; 9479154b1bSChris Mason } 9579154b1bSChris Mason 96d352ac68SChris Mason /* 97d397712bSChris Mason * this does all the record keeping required to make sure that a reference 98d397712bSChris Mason * counted root is properly recorded in a given transaction. This is required 99d397712bSChris Mason * to make sure the old root from before we joined the transaction is deleted 100d397712bSChris Mason * when the transaction commits 101d352ac68SChris Mason */ 1025d4f98a2SYan Zheng static noinline int record_root_in_trans(struct btrfs_trans_handle *trans, 1035d4f98a2SYan Zheng struct btrfs_root *root) 1046702ed49SChris Mason { 1055d4f98a2SYan Zheng if (root->ref_cows && root->last_trans < trans->transid) { 1066702ed49SChris Mason WARN_ON(root == root->fs_info->extent_root); 1075d4f98a2SYan Zheng WARN_ON(root->commit_root != root->node); 1085d4f98a2SYan Zheng 1096702ed49SChris Mason radix_tree_tag_set(&root->fs_info->fs_roots_radix, 1106702ed49SChris Mason (unsigned long)root->root_key.objectid, 1116702ed49SChris Mason BTRFS_ROOT_TRANS_TAG); 1125d4f98a2SYan Zheng root->last_trans = trans->transid; 1135d4f98a2SYan Zheng btrfs_init_reloc_root(trans, root); 1146702ed49SChris Mason } 1155d4f98a2SYan Zheng return 0; 1166702ed49SChris Mason } 1175d4f98a2SYan Zheng 1185d4f98a2SYan Zheng int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, 1195d4f98a2SYan Zheng struct btrfs_root *root) 1205d4f98a2SYan Zheng { 1215d4f98a2SYan Zheng if (!root->ref_cows) 1225d4f98a2SYan Zheng return 0; 1235d4f98a2SYan Zheng 1245d4f98a2SYan Zheng mutex_lock(&root->fs_info->trans_mutex); 1255d4f98a2SYan Zheng if (root->last_trans == trans->transid) { 1265d4f98a2SYan Zheng mutex_unlock(&root->fs_info->trans_mutex); 1275d4f98a2SYan Zheng return 0; 1285d4f98a2SYan Zheng } 1295d4f98a2SYan Zheng 1305d4f98a2SYan Zheng record_root_in_trans(trans, root); 1315d4f98a2SYan Zheng mutex_unlock(&root->fs_info->trans_mutex); 1326702ed49SChris Mason return 0; 1336702ed49SChris Mason } 1346702ed49SChris Mason 135d352ac68SChris Mason /* wait for commit against the current transaction to become unblocked 136d352ac68SChris Mason * when this is done, it is safe to start a new transaction, but the current 137d352ac68SChris Mason * transaction might not be fully on disk. 138d352ac68SChris Mason */ 13937d1aeeeSChris Mason static void wait_current_trans(struct btrfs_root *root) 14079154b1bSChris Mason { 141f9295749SChris Mason struct btrfs_transaction *cur_trans; 14279154b1bSChris Mason 143f9295749SChris Mason cur_trans = root->fs_info->running_transaction; 14437d1aeeeSChris Mason if (cur_trans && cur_trans->blocked) { 145f9295749SChris Mason DEFINE_WAIT(wait); 14613c5a93eSJosef Bacik atomic_inc(&cur_trans->use_count); 147f9295749SChris Mason while (1) { 148f9295749SChris Mason prepare_to_wait(&root->fs_info->transaction_wait, &wait, 149f9295749SChris Mason TASK_UNINTERRUPTIBLE); 150471fa17dSZhao Lei if (!cur_trans->blocked) 151471fa17dSZhao Lei break; 152f9295749SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 153f9295749SChris Mason schedule(); 154f9295749SChris Mason mutex_lock(&root->fs_info->trans_mutex); 155f9295749SChris Mason } 156471fa17dSZhao Lei finish_wait(&root->fs_info->transaction_wait, &wait); 157f9295749SChris Mason put_transaction(cur_trans); 158f9295749SChris Mason } 15937d1aeeeSChris Mason } 16037d1aeeeSChris Mason 161249ac1e5SJosef Bacik enum btrfs_trans_type { 162249ac1e5SJosef Bacik TRANS_START, 163249ac1e5SJosef Bacik TRANS_JOIN, 164249ac1e5SJosef Bacik TRANS_USERSPACE, 1650af3d00bSJosef Bacik TRANS_JOIN_NOLOCK, 166249ac1e5SJosef Bacik }; 167249ac1e5SJosef Bacik 168a22285a6SYan, Zheng static int may_wait_transaction(struct btrfs_root *root, int type) 16937d1aeeeSChris Mason { 1704bef0848SChris Mason if (!root->fs_info->log_root_recovering && 171249ac1e5SJosef Bacik ((type == TRANS_START && !root->fs_info->open_ioctl_trans) || 172249ac1e5SJosef Bacik type == TRANS_USERSPACE)) 173a22285a6SYan, Zheng return 1; 174a22285a6SYan, Zheng return 0; 175a22285a6SYan, Zheng } 176a22285a6SYan, Zheng 177a22285a6SYan, Zheng static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root, 178a22285a6SYan, Zheng u64 num_items, int type) 179a22285a6SYan, Zheng { 180a22285a6SYan, Zheng struct btrfs_trans_handle *h; 181a22285a6SYan, Zheng struct btrfs_transaction *cur_trans; 18206d5a589SJosef Bacik int retries = 0; 183a22285a6SYan, Zheng int ret; 184acce952bSliubo 185acce952bSliubo if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) 186acce952bSliubo return ERR_PTR(-EROFS); 1872a1eb461SJosef Bacik 1882a1eb461SJosef Bacik if (current->journal_info) { 1892a1eb461SJosef Bacik WARN_ON(type != TRANS_JOIN && type != TRANS_JOIN_NOLOCK); 1902a1eb461SJosef Bacik h = current->journal_info; 1912a1eb461SJosef Bacik h->use_count++; 1922a1eb461SJosef Bacik h->orig_rsv = h->block_rsv; 1932a1eb461SJosef Bacik h->block_rsv = NULL; 1942a1eb461SJosef Bacik goto got_it; 1952a1eb461SJosef Bacik } 196a22285a6SYan, Zheng again: 197a22285a6SYan, Zheng h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS); 198a22285a6SYan, Zheng if (!h) 199a22285a6SYan, Zheng return ERR_PTR(-ENOMEM); 200a22285a6SYan, Zheng 2010af3d00bSJosef Bacik if (type != TRANS_JOIN_NOLOCK) 202a22285a6SYan, Zheng mutex_lock(&root->fs_info->trans_mutex); 203a22285a6SYan, Zheng if (may_wait_transaction(root, type)) 20437d1aeeeSChris Mason wait_current_trans(root); 205a22285a6SYan, Zheng 20679154b1bSChris Mason ret = join_transaction(root); 207db5b493aSTsutomu Itoh if (ret < 0) { 2086e8df2aeSYoshinori Sano kmem_cache_free(btrfs_trans_handle_cachep, h); 209db5b493aSTsutomu Itoh if (type != TRANS_JOIN_NOLOCK) 210db5b493aSTsutomu Itoh mutex_unlock(&root->fs_info->trans_mutex); 211db5b493aSTsutomu Itoh return ERR_PTR(ret); 212db5b493aSTsutomu Itoh } 2130f7d52f4SChris Mason 214a22285a6SYan, Zheng cur_trans = root->fs_info->running_transaction; 21513c5a93eSJosef Bacik atomic_inc(&cur_trans->use_count); 2160af3d00bSJosef Bacik if (type != TRANS_JOIN_NOLOCK) 217a22285a6SYan, Zheng mutex_unlock(&root->fs_info->trans_mutex); 218a22285a6SYan, Zheng 219a22285a6SYan, Zheng h->transid = cur_trans->transid; 220a22285a6SYan, Zheng h->transaction = cur_trans; 22179154b1bSChris Mason h->blocks_used = 0; 222d2fb3437SYan Zheng h->block_group = 0; 223a22285a6SYan, Zheng h->bytes_reserved = 0; 22456bec294SChris Mason h->delayed_ref_updates = 0; 2252a1eb461SJosef Bacik h->use_count = 1; 226f0486c68SYan, Zheng h->block_rsv = NULL; 2272a1eb461SJosef Bacik h->orig_rsv = NULL; 228b7ec40d7SChris Mason 229a22285a6SYan, Zheng smp_mb(); 230a22285a6SYan, Zheng if (cur_trans->blocked && may_wait_transaction(root, type)) { 231a22285a6SYan, Zheng btrfs_commit_transaction(h, root); 232a22285a6SYan, Zheng goto again; 233a22285a6SYan, Zheng } 2349ed74f2dSJosef Bacik 235a22285a6SYan, Zheng if (num_items > 0) { 2368bb8ab2eSJosef Bacik ret = btrfs_trans_reserve_metadata(h, root, num_items); 23706d5a589SJosef Bacik if (ret == -EAGAIN && !retries) { 23806d5a589SJosef Bacik retries++; 239a22285a6SYan, Zheng btrfs_commit_transaction(h, root); 240a22285a6SYan, Zheng goto again; 24106d5a589SJosef Bacik } else if (ret == -EAGAIN) { 24206d5a589SJosef Bacik /* 24306d5a589SJosef Bacik * We have already retried and got EAGAIN, so really we 24406d5a589SJosef Bacik * don't have space, so set ret to -ENOSPC. 24506d5a589SJosef Bacik */ 24606d5a589SJosef Bacik ret = -ENOSPC; 247a22285a6SYan, Zheng } 24806d5a589SJosef Bacik 249a22285a6SYan, Zheng if (ret < 0) { 250a22285a6SYan, Zheng btrfs_end_transaction(h, root); 251a22285a6SYan, Zheng return ERR_PTR(ret); 252a22285a6SYan, Zheng } 253a22285a6SYan, Zheng } 254a22285a6SYan, Zheng 2552a1eb461SJosef Bacik got_it: 2560af3d00bSJosef Bacik if (type != TRANS_JOIN_NOLOCK) 257a22285a6SYan, Zheng mutex_lock(&root->fs_info->trans_mutex); 2585d4f98a2SYan Zheng record_root_in_trans(h, root); 2590af3d00bSJosef Bacik if (type != TRANS_JOIN_NOLOCK) 26079154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 261a22285a6SYan, Zheng 262a22285a6SYan, Zheng if (!current->journal_info && type != TRANS_USERSPACE) 263a22285a6SYan, Zheng current->journal_info = h; 26479154b1bSChris Mason return h; 26579154b1bSChris Mason } 26679154b1bSChris Mason 267f9295749SChris Mason struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, 268a22285a6SYan, Zheng int num_items) 269f9295749SChris Mason { 270a22285a6SYan, Zheng return start_transaction(root, num_items, TRANS_START); 271f9295749SChris Mason } 2727a7eaa40SJosef Bacik struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root) 273f9295749SChris Mason { 274a22285a6SYan, Zheng return start_transaction(root, 0, TRANS_JOIN); 275f9295749SChris Mason } 276f9295749SChris Mason 2777a7eaa40SJosef Bacik struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root) 2780af3d00bSJosef Bacik { 2790af3d00bSJosef Bacik return start_transaction(root, 0, TRANS_JOIN_NOLOCK); 2800af3d00bSJosef Bacik } 2810af3d00bSJosef Bacik 2827a7eaa40SJosef Bacik struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root) 2839ca9ee09SSage Weil { 2847a7eaa40SJosef Bacik return start_transaction(root, 0, TRANS_USERSPACE); 2859ca9ee09SSage Weil } 2869ca9ee09SSage Weil 287d352ac68SChris Mason /* wait for a transaction commit to be fully complete */ 28889ce8a63SChris Mason static noinline int wait_for_commit(struct btrfs_root *root, 28989ce8a63SChris Mason struct btrfs_transaction *commit) 29089ce8a63SChris Mason { 29189ce8a63SChris Mason DEFINE_WAIT(wait); 29289ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 29389ce8a63SChris Mason while (!commit->commit_done) { 29489ce8a63SChris Mason prepare_to_wait(&commit->commit_wait, &wait, 29589ce8a63SChris Mason TASK_UNINTERRUPTIBLE); 29689ce8a63SChris Mason if (commit->commit_done) 29789ce8a63SChris Mason break; 29889ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 29989ce8a63SChris Mason schedule(); 30089ce8a63SChris Mason mutex_lock(&root->fs_info->trans_mutex); 30189ce8a63SChris Mason } 30289ce8a63SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 30389ce8a63SChris Mason finish_wait(&commit->commit_wait, &wait); 30489ce8a63SChris Mason return 0; 30589ce8a63SChris Mason } 30689ce8a63SChris Mason 30746204592SSage Weil int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid) 30846204592SSage Weil { 30946204592SSage Weil struct btrfs_transaction *cur_trans = NULL, *t; 31046204592SSage Weil int ret; 31146204592SSage Weil 31246204592SSage Weil mutex_lock(&root->fs_info->trans_mutex); 31346204592SSage Weil 31446204592SSage Weil ret = 0; 31546204592SSage Weil if (transid) { 31646204592SSage Weil if (transid <= root->fs_info->last_trans_committed) 31746204592SSage Weil goto out_unlock; 31846204592SSage Weil 31946204592SSage Weil /* find specified transaction */ 32046204592SSage Weil list_for_each_entry(t, &root->fs_info->trans_list, list) { 32146204592SSage Weil if (t->transid == transid) { 32246204592SSage Weil cur_trans = t; 32346204592SSage Weil break; 32446204592SSage Weil } 32546204592SSage Weil if (t->transid > transid) 32646204592SSage Weil break; 32746204592SSage Weil } 32846204592SSage Weil ret = -EINVAL; 32946204592SSage Weil if (!cur_trans) 33046204592SSage Weil goto out_unlock; /* bad transid */ 33146204592SSage Weil } else { 33246204592SSage Weil /* find newest transaction that is committing | committed */ 33346204592SSage Weil list_for_each_entry_reverse(t, &root->fs_info->trans_list, 33446204592SSage Weil list) { 33546204592SSage Weil if (t->in_commit) { 33646204592SSage Weil if (t->commit_done) 33746204592SSage Weil goto out_unlock; 33846204592SSage Weil cur_trans = t; 33946204592SSage Weil break; 34046204592SSage Weil } 34146204592SSage Weil } 34246204592SSage Weil if (!cur_trans) 34346204592SSage Weil goto out_unlock; /* nothing committing|committed */ 34446204592SSage Weil } 34546204592SSage Weil 34613c5a93eSJosef Bacik atomic_inc(&cur_trans->use_count); 34746204592SSage Weil mutex_unlock(&root->fs_info->trans_mutex); 34846204592SSage Weil 34946204592SSage Weil wait_for_commit(root, cur_trans); 35046204592SSage Weil 35146204592SSage Weil mutex_lock(&root->fs_info->trans_mutex); 35246204592SSage Weil put_transaction(cur_trans); 35346204592SSage Weil ret = 0; 35446204592SSage Weil out_unlock: 35546204592SSage Weil mutex_unlock(&root->fs_info->trans_mutex); 35646204592SSage Weil return ret; 35746204592SSage Weil } 35846204592SSage Weil 3595d4f98a2SYan Zheng #if 0 360d352ac68SChris Mason /* 361d397712bSChris Mason * rate limit against the drop_snapshot code. This helps to slow down new 362d397712bSChris Mason * operations if the drop_snapshot code isn't able to keep up. 363d352ac68SChris Mason */ 36437d1aeeeSChris Mason static void throttle_on_drops(struct btrfs_root *root) 365ab78c84dSChris Mason { 366ab78c84dSChris Mason struct btrfs_fs_info *info = root->fs_info; 3672dd3e67bSChris Mason int harder_count = 0; 368ab78c84dSChris Mason 3692dd3e67bSChris Mason harder: 370ab78c84dSChris Mason if (atomic_read(&info->throttles)) { 371ab78c84dSChris Mason DEFINE_WAIT(wait); 372ab78c84dSChris Mason int thr; 373ab78c84dSChris Mason thr = atomic_read(&info->throttle_gen); 374ab78c84dSChris Mason 375ab78c84dSChris Mason do { 376ab78c84dSChris Mason prepare_to_wait(&info->transaction_throttle, 377ab78c84dSChris Mason &wait, TASK_UNINTERRUPTIBLE); 378ab78c84dSChris Mason if (!atomic_read(&info->throttles)) { 379ab78c84dSChris Mason finish_wait(&info->transaction_throttle, &wait); 380ab78c84dSChris Mason break; 381ab78c84dSChris Mason } 382ab78c84dSChris Mason schedule(); 383ab78c84dSChris Mason finish_wait(&info->transaction_throttle, &wait); 384ab78c84dSChris Mason } while (thr == atomic_read(&info->throttle_gen)); 3852dd3e67bSChris Mason harder_count++; 3862dd3e67bSChris Mason 3872dd3e67bSChris Mason if (root->fs_info->total_ref_cache_size > 1 * 1024 * 1024 && 3882dd3e67bSChris Mason harder_count < 2) 3892dd3e67bSChris Mason goto harder; 3902dd3e67bSChris Mason 3912dd3e67bSChris Mason if (root->fs_info->total_ref_cache_size > 5 * 1024 * 1024 && 3922dd3e67bSChris Mason harder_count < 10) 3932dd3e67bSChris Mason goto harder; 3942dd3e67bSChris Mason 3952dd3e67bSChris Mason if (root->fs_info->total_ref_cache_size > 10 * 1024 * 1024 && 3962dd3e67bSChris Mason harder_count < 20) 3972dd3e67bSChris Mason goto harder; 398ab78c84dSChris Mason } 399ab78c84dSChris Mason } 4005d4f98a2SYan Zheng #endif 401ab78c84dSChris Mason 40237d1aeeeSChris Mason void btrfs_throttle(struct btrfs_root *root) 40337d1aeeeSChris Mason { 40437d1aeeeSChris Mason mutex_lock(&root->fs_info->trans_mutex); 4059ca9ee09SSage Weil if (!root->fs_info->open_ioctl_trans) 40637d1aeeeSChris Mason wait_current_trans(root); 40737d1aeeeSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 40837d1aeeeSChris Mason } 40937d1aeeeSChris Mason 4108929ecfaSYan, Zheng static int should_end_transaction(struct btrfs_trans_handle *trans, 4118929ecfaSYan, Zheng struct btrfs_root *root) 4128929ecfaSYan, Zheng { 4138929ecfaSYan, Zheng int ret; 4148929ecfaSYan, Zheng ret = btrfs_block_rsv_check(trans, root, 4158929ecfaSYan, Zheng &root->fs_info->global_block_rsv, 0, 5); 4168929ecfaSYan, Zheng return ret ? 1 : 0; 4178929ecfaSYan, Zheng } 4188929ecfaSYan, Zheng 4198929ecfaSYan, Zheng int btrfs_should_end_transaction(struct btrfs_trans_handle *trans, 4208929ecfaSYan, Zheng struct btrfs_root *root) 4218929ecfaSYan, Zheng { 4228929ecfaSYan, Zheng struct btrfs_transaction *cur_trans = trans->transaction; 4238929ecfaSYan, Zheng int updates; 4248929ecfaSYan, Zheng 4258929ecfaSYan, Zheng if (cur_trans->blocked || cur_trans->delayed_refs.flushing) 4268929ecfaSYan, Zheng return 1; 4278929ecfaSYan, Zheng 4288929ecfaSYan, Zheng updates = trans->delayed_ref_updates; 4298929ecfaSYan, Zheng trans->delayed_ref_updates = 0; 4308929ecfaSYan, Zheng if (updates) 4318929ecfaSYan, Zheng btrfs_run_delayed_refs(trans, root, updates); 4328929ecfaSYan, Zheng 4338929ecfaSYan, Zheng return should_end_transaction(trans, root); 4348929ecfaSYan, Zheng } 4358929ecfaSYan, Zheng 43689ce8a63SChris Mason static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, 4370af3d00bSJosef Bacik struct btrfs_root *root, int throttle, int lock) 43879154b1bSChris Mason { 4398929ecfaSYan, Zheng struct btrfs_transaction *cur_trans = trans->transaction; 440ab78c84dSChris Mason struct btrfs_fs_info *info = root->fs_info; 441c3e69d58SChris Mason int count = 0; 442d6e4a428SChris Mason 4432a1eb461SJosef Bacik if (--trans->use_count) { 4442a1eb461SJosef Bacik trans->block_rsv = trans->orig_rsv; 4452a1eb461SJosef Bacik return 0; 4462a1eb461SJosef Bacik } 4472a1eb461SJosef Bacik 448c3e69d58SChris Mason while (count < 4) { 449c3e69d58SChris Mason unsigned long cur = trans->delayed_ref_updates; 450c3e69d58SChris Mason trans->delayed_ref_updates = 0; 451c3e69d58SChris Mason if (cur && 452c3e69d58SChris Mason trans->transaction->delayed_refs.num_heads_ready > 64) { 453c3e69d58SChris Mason trans->delayed_ref_updates = 0; 454b7ec40d7SChris Mason 455b7ec40d7SChris Mason /* 456b7ec40d7SChris Mason * do a full flush if the transaction is trying 457b7ec40d7SChris Mason * to close 458b7ec40d7SChris Mason */ 459b7ec40d7SChris Mason if (trans->transaction->delayed_refs.flushing) 460b7ec40d7SChris Mason cur = 0; 461c3e69d58SChris Mason btrfs_run_delayed_refs(trans, root, cur); 462c3e69d58SChris Mason } else { 463c3e69d58SChris Mason break; 464c3e69d58SChris Mason } 465c3e69d58SChris Mason count++; 46656bec294SChris Mason } 46756bec294SChris Mason 468a22285a6SYan, Zheng btrfs_trans_release_metadata(trans, root); 469a22285a6SYan, Zheng 4700af3d00bSJosef Bacik if (lock && !root->fs_info->open_ioctl_trans && 4718929ecfaSYan, Zheng should_end_transaction(trans, root)) 4728929ecfaSYan, Zheng trans->transaction->blocked = 1; 4738929ecfaSYan, Zheng 4740af3d00bSJosef Bacik if (lock && cur_trans->blocked && !cur_trans->in_commit) { 4758929ecfaSYan, Zheng if (throttle) 4768929ecfaSYan, Zheng return btrfs_commit_transaction(trans, root); 4778929ecfaSYan, Zheng else 4788929ecfaSYan, Zheng wake_up_process(info->transaction_kthread); 4798929ecfaSYan, Zheng } 4808929ecfaSYan, Zheng 4818929ecfaSYan, Zheng WARN_ON(cur_trans != info->running_transaction); 48213c5a93eSJosef Bacik WARN_ON(atomic_read(&cur_trans->num_writers) < 1); 48313c5a93eSJosef Bacik atomic_dec(&cur_trans->num_writers); 48489ce8a63SChris Mason 48599d16cbcSSage Weil smp_mb(); 48679154b1bSChris Mason if (waitqueue_active(&cur_trans->writer_wait)) 48779154b1bSChris Mason wake_up(&cur_trans->writer_wait); 48879154b1bSChris Mason put_transaction(cur_trans); 4899ed74f2dSJosef Bacik 4909ed74f2dSJosef Bacik if (current->journal_info == trans) 4919ed74f2dSJosef Bacik current->journal_info = NULL; 492d6025579SChris Mason memset(trans, 0, sizeof(*trans)); 4932c90e5d6SChris Mason kmem_cache_free(btrfs_trans_handle_cachep, trans); 494ab78c84dSChris Mason 49524bbcf04SYan, Zheng if (throttle) 49624bbcf04SYan, Zheng btrfs_run_delayed_iputs(root); 49724bbcf04SYan, Zheng 49879154b1bSChris Mason return 0; 49979154b1bSChris Mason } 50079154b1bSChris Mason 50189ce8a63SChris Mason int btrfs_end_transaction(struct btrfs_trans_handle *trans, 50289ce8a63SChris Mason struct btrfs_root *root) 50389ce8a63SChris Mason { 5040af3d00bSJosef Bacik return __btrfs_end_transaction(trans, root, 0, 1); 50589ce8a63SChris Mason } 50689ce8a63SChris Mason 50789ce8a63SChris Mason int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, 50889ce8a63SChris Mason struct btrfs_root *root) 50989ce8a63SChris Mason { 5100af3d00bSJosef Bacik return __btrfs_end_transaction(trans, root, 1, 1); 5110af3d00bSJosef Bacik } 5120af3d00bSJosef Bacik 5130af3d00bSJosef Bacik int btrfs_end_transaction_nolock(struct btrfs_trans_handle *trans, 5140af3d00bSJosef Bacik struct btrfs_root *root) 5150af3d00bSJosef Bacik { 5160af3d00bSJosef Bacik return __btrfs_end_transaction(trans, root, 0, 0); 51789ce8a63SChris Mason } 51889ce8a63SChris Mason 519d352ac68SChris Mason /* 520d352ac68SChris Mason * when btree blocks are allocated, they have some corresponding bits set for 521d352ac68SChris Mason * them in one of two extent_io trees. This is used to make sure all of 522690587d1SChris Mason * those extents are sent to disk but does not wait on them 523d352ac68SChris Mason */ 524690587d1SChris Mason int btrfs_write_marked_extents(struct btrfs_root *root, 5258cef4e16SYan, Zheng struct extent_io_tree *dirty_pages, int mark) 52679154b1bSChris Mason { 5277c4452b9SChris Mason int ret; 528777e6bd7SChris Mason int err = 0; 5297c4452b9SChris Mason int werr = 0; 5307c4452b9SChris Mason struct page *page; 5317c4452b9SChris Mason struct inode *btree_inode = root->fs_info->btree_inode; 532777e6bd7SChris Mason u64 start = 0; 5335f39d397SChris Mason u64 end; 5345f39d397SChris Mason unsigned long index; 5357c4452b9SChris Mason 5367c4452b9SChris Mason while (1) { 537777e6bd7SChris Mason ret = find_first_extent_bit(dirty_pages, start, &start, &end, 5388cef4e16SYan, Zheng mark); 5395f39d397SChris Mason if (ret) 5407c4452b9SChris Mason break; 5415f39d397SChris Mason while (start <= end) { 542777e6bd7SChris Mason cond_resched(); 543777e6bd7SChris Mason 5445f39d397SChris Mason index = start >> PAGE_CACHE_SHIFT; 54535ebb934SChris Mason start = (u64)(index + 1) << PAGE_CACHE_SHIFT; 5464bef0848SChris Mason page = find_get_page(btree_inode->i_mapping, index); 5477c4452b9SChris Mason if (!page) 5487c4452b9SChris Mason continue; 5494bef0848SChris Mason 5504bef0848SChris Mason btree_lock_page_hook(page); 5514bef0848SChris Mason if (!page->mapping) { 5524bef0848SChris Mason unlock_page(page); 5534bef0848SChris Mason page_cache_release(page); 5544bef0848SChris Mason continue; 5554bef0848SChris Mason } 5564bef0848SChris Mason 5576702ed49SChris Mason if (PageWriteback(page)) { 5586702ed49SChris Mason if (PageDirty(page)) 5596702ed49SChris Mason wait_on_page_writeback(page); 5606702ed49SChris Mason else { 5616702ed49SChris Mason unlock_page(page); 5626702ed49SChris Mason page_cache_release(page); 5636702ed49SChris Mason continue; 5646702ed49SChris Mason } 5656702ed49SChris Mason } 5667c4452b9SChris Mason err = write_one_page(page, 0); 5677c4452b9SChris Mason if (err) 5687c4452b9SChris Mason werr = err; 5697c4452b9SChris Mason page_cache_release(page); 5707c4452b9SChris Mason } 5717c4452b9SChris Mason } 572690587d1SChris Mason if (err) 573690587d1SChris Mason werr = err; 574690587d1SChris Mason return werr; 575690587d1SChris Mason } 576690587d1SChris Mason 577690587d1SChris Mason /* 578690587d1SChris Mason * when btree blocks are allocated, they have some corresponding bits set for 579690587d1SChris Mason * them in one of two extent_io trees. This is used to make sure all of 580690587d1SChris Mason * those extents are on disk for transaction or log commit. We wait 581690587d1SChris Mason * on all the pages and clear them from the dirty pages state tree 582690587d1SChris Mason */ 583690587d1SChris Mason int btrfs_wait_marked_extents(struct btrfs_root *root, 5848cef4e16SYan, Zheng struct extent_io_tree *dirty_pages, int mark) 585690587d1SChris Mason { 586690587d1SChris Mason int ret; 587690587d1SChris Mason int err = 0; 588690587d1SChris Mason int werr = 0; 589690587d1SChris Mason struct page *page; 590690587d1SChris Mason struct inode *btree_inode = root->fs_info->btree_inode; 591690587d1SChris Mason u64 start = 0; 592690587d1SChris Mason u64 end; 593690587d1SChris Mason unsigned long index; 594690587d1SChris Mason 595777e6bd7SChris Mason while (1) { 5968cef4e16SYan, Zheng ret = find_first_extent_bit(dirty_pages, start, &start, &end, 5978cef4e16SYan, Zheng mark); 598777e6bd7SChris Mason if (ret) 599777e6bd7SChris Mason break; 600777e6bd7SChris Mason 6018cef4e16SYan, Zheng clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS); 602777e6bd7SChris Mason while (start <= end) { 603777e6bd7SChris Mason index = start >> PAGE_CACHE_SHIFT; 604777e6bd7SChris Mason start = (u64)(index + 1) << PAGE_CACHE_SHIFT; 605777e6bd7SChris Mason page = find_get_page(btree_inode->i_mapping, index); 606777e6bd7SChris Mason if (!page) 607777e6bd7SChris Mason continue; 608777e6bd7SChris Mason if (PageDirty(page)) { 6094bef0848SChris Mason btree_lock_page_hook(page); 6104bef0848SChris Mason wait_on_page_writeback(page); 611777e6bd7SChris Mason err = write_one_page(page, 0); 612777e6bd7SChris Mason if (err) 613777e6bd7SChris Mason werr = err; 614777e6bd7SChris Mason } 615777e6bd7SChris Mason wait_on_page_writeback(page); 616777e6bd7SChris Mason page_cache_release(page); 617777e6bd7SChris Mason cond_resched(); 618777e6bd7SChris Mason } 619777e6bd7SChris Mason } 6207c4452b9SChris Mason if (err) 6217c4452b9SChris Mason werr = err; 6227c4452b9SChris Mason return werr; 62379154b1bSChris Mason } 62479154b1bSChris Mason 625690587d1SChris Mason /* 626690587d1SChris Mason * when btree blocks are allocated, they have some corresponding bits set for 627690587d1SChris Mason * them in one of two extent_io trees. This is used to make sure all of 628690587d1SChris Mason * those extents are on disk for transaction or log commit 629690587d1SChris Mason */ 630690587d1SChris Mason int btrfs_write_and_wait_marked_extents(struct btrfs_root *root, 6318cef4e16SYan, Zheng struct extent_io_tree *dirty_pages, int mark) 632690587d1SChris Mason { 633690587d1SChris Mason int ret; 634690587d1SChris Mason int ret2; 635690587d1SChris Mason 6368cef4e16SYan, Zheng ret = btrfs_write_marked_extents(root, dirty_pages, mark); 6378cef4e16SYan, Zheng ret2 = btrfs_wait_marked_extents(root, dirty_pages, mark); 638690587d1SChris Mason return ret || ret2; 639690587d1SChris Mason } 640690587d1SChris Mason 641d0c803c4SChris Mason int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, 642d0c803c4SChris Mason struct btrfs_root *root) 643d0c803c4SChris Mason { 644d0c803c4SChris Mason if (!trans || !trans->transaction) { 645d0c803c4SChris Mason struct inode *btree_inode; 646d0c803c4SChris Mason btree_inode = root->fs_info->btree_inode; 647d0c803c4SChris Mason return filemap_write_and_wait(btree_inode->i_mapping); 648d0c803c4SChris Mason } 649d0c803c4SChris Mason return btrfs_write_and_wait_marked_extents(root, 6508cef4e16SYan, Zheng &trans->transaction->dirty_pages, 6518cef4e16SYan, Zheng EXTENT_DIRTY); 652d0c803c4SChris Mason } 653d0c803c4SChris Mason 654d352ac68SChris Mason /* 655d352ac68SChris Mason * this is used to update the root pointer in the tree of tree roots. 656d352ac68SChris Mason * 657d352ac68SChris Mason * But, in the case of the extent allocation tree, updating the root 658d352ac68SChris Mason * pointer may allocate blocks which may change the root of the extent 659d352ac68SChris Mason * allocation tree. 660d352ac68SChris Mason * 661d352ac68SChris Mason * So, this loops and repeats and makes sure the cowonly root didn't 662d352ac68SChris Mason * change while the root pointer was being updated in the metadata. 663d352ac68SChris Mason */ 6640b86a832SChris Mason static int update_cowonly_root(struct btrfs_trans_handle *trans, 66579154b1bSChris Mason struct btrfs_root *root) 66679154b1bSChris Mason { 66779154b1bSChris Mason int ret; 6680b86a832SChris Mason u64 old_root_bytenr; 66986b9f2ecSYan, Zheng u64 old_root_used; 6700b86a832SChris Mason struct btrfs_root *tree_root = root->fs_info->tree_root; 67179154b1bSChris Mason 67286b9f2ecSYan, Zheng old_root_used = btrfs_root_used(&root->root_item); 6730b86a832SChris Mason btrfs_write_dirty_block_groups(trans, root); 67456bec294SChris Mason 67579154b1bSChris Mason while (1) { 6760b86a832SChris Mason old_root_bytenr = btrfs_root_bytenr(&root->root_item); 67786b9f2ecSYan, Zheng if (old_root_bytenr == root->node->start && 67886b9f2ecSYan, Zheng old_root_used == btrfs_root_used(&root->root_item)) 67979154b1bSChris Mason break; 68087ef2bb4SChris Mason 6815d4f98a2SYan Zheng btrfs_set_root_node(&root->root_item, root->node); 68279154b1bSChris Mason ret = btrfs_update_root(trans, tree_root, 6830b86a832SChris Mason &root->root_key, 6840b86a832SChris Mason &root->root_item); 68579154b1bSChris Mason BUG_ON(ret); 68656bec294SChris Mason 68786b9f2ecSYan, Zheng old_root_used = btrfs_root_used(&root->root_item); 6884a8c9a62SYan Zheng ret = btrfs_write_dirty_block_groups(trans, root); 68956bec294SChris Mason BUG_ON(ret); 6900b86a832SChris Mason } 691276e680dSYan Zheng 692276e680dSYan Zheng if (root != root->fs_info->extent_root) 693817d52f8SJosef Bacik switch_commit_root(root); 694276e680dSYan Zheng 6950b86a832SChris Mason return 0; 6960b86a832SChris Mason } 6970b86a832SChris Mason 698d352ac68SChris Mason /* 699d352ac68SChris Mason * update all the cowonly tree roots on disk 700d352ac68SChris Mason */ 7015d4f98a2SYan Zheng static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans, 7020b86a832SChris Mason struct btrfs_root *root) 7030b86a832SChris Mason { 7040b86a832SChris Mason struct btrfs_fs_info *fs_info = root->fs_info; 7050b86a832SChris Mason struct list_head *next; 70684234f3aSYan Zheng struct extent_buffer *eb; 70756bec294SChris Mason int ret; 70884234f3aSYan Zheng 70956bec294SChris Mason ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); 71056bec294SChris Mason BUG_ON(ret); 71187ef2bb4SChris Mason 71284234f3aSYan Zheng eb = btrfs_lock_root_node(fs_info->tree_root); 7139fa8cfe7SChris Mason btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb); 71484234f3aSYan Zheng btrfs_tree_unlock(eb); 71584234f3aSYan Zheng free_extent_buffer(eb); 7160b86a832SChris Mason 71756bec294SChris Mason ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); 71856bec294SChris Mason BUG_ON(ret); 71987ef2bb4SChris Mason 7200b86a832SChris Mason while (!list_empty(&fs_info->dirty_cowonly_roots)) { 7210b86a832SChris Mason next = fs_info->dirty_cowonly_roots.next; 7220b86a832SChris Mason list_del_init(next); 7230b86a832SChris Mason root = list_entry(next, struct btrfs_root, dirty_list); 72487ef2bb4SChris Mason 7250b86a832SChris Mason update_cowonly_root(trans, root); 72679154b1bSChris Mason } 727276e680dSYan Zheng 728276e680dSYan Zheng down_write(&fs_info->extent_commit_sem); 729276e680dSYan Zheng switch_commit_root(fs_info->extent_root); 730276e680dSYan Zheng up_write(&fs_info->extent_commit_sem); 731276e680dSYan Zheng 73279154b1bSChris Mason return 0; 73379154b1bSChris Mason } 73479154b1bSChris Mason 735d352ac68SChris Mason /* 736d352ac68SChris Mason * dead roots are old snapshots that need to be deleted. This allocates 737d352ac68SChris Mason * a dirty root struct and adds it into the list of dead roots that need to 738d352ac68SChris Mason * be deleted 739d352ac68SChris Mason */ 7405d4f98a2SYan Zheng int btrfs_add_dead_root(struct btrfs_root *root) 7415eda7b5eSChris Mason { 742b48652c1SYan Zheng mutex_lock(&root->fs_info->trans_mutex); 7435d4f98a2SYan Zheng list_add(&root->root_list, &root->fs_info->dead_roots); 744b48652c1SYan Zheng mutex_unlock(&root->fs_info->trans_mutex); 7455eda7b5eSChris Mason return 0; 7465eda7b5eSChris Mason } 7475eda7b5eSChris Mason 748d352ac68SChris Mason /* 7495d4f98a2SYan Zheng * update all the cowonly tree roots on disk 750d352ac68SChris Mason */ 7515d4f98a2SYan Zheng static noinline int commit_fs_roots(struct btrfs_trans_handle *trans, 7525d4f98a2SYan Zheng struct btrfs_root *root) 7530f7d52f4SChris Mason { 7540f7d52f4SChris Mason struct btrfs_root *gang[8]; 7555d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = root->fs_info; 7560f7d52f4SChris Mason int i; 7570f7d52f4SChris Mason int ret; 75854aa1f4dSChris Mason int err = 0; 75954aa1f4dSChris Mason 7600f7d52f4SChris Mason while (1) { 7615d4f98a2SYan Zheng ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix, 7625d4f98a2SYan Zheng (void **)gang, 0, 7630f7d52f4SChris Mason ARRAY_SIZE(gang), 7640f7d52f4SChris Mason BTRFS_ROOT_TRANS_TAG); 7650f7d52f4SChris Mason if (ret == 0) 7660f7d52f4SChris Mason break; 7670f7d52f4SChris Mason for (i = 0; i < ret; i++) { 7680f7d52f4SChris Mason root = gang[i]; 7695d4f98a2SYan Zheng radix_tree_tag_clear(&fs_info->fs_roots_radix, 7702619ba1fSChris Mason (unsigned long)root->root_key.objectid, 7710f7d52f4SChris Mason BTRFS_ROOT_TRANS_TAG); 77231153d81SYan Zheng 773e02119d5SChris Mason btrfs_free_log(trans, root); 7745d4f98a2SYan Zheng btrfs_update_reloc_root(trans, root); 775d68fc57bSYan, Zheng btrfs_orphan_commit_root(trans, root); 776e02119d5SChris Mason 777978d910dSYan Zheng if (root->commit_root != root->node) { 778817d52f8SJosef Bacik switch_commit_root(root); 779978d910dSYan Zheng btrfs_set_root_node(&root->root_item, 780978d910dSYan Zheng root->node); 781978d910dSYan Zheng } 78231153d81SYan Zheng 7835d4f98a2SYan Zheng err = btrfs_update_root(trans, fs_info->tree_root, 7840f7d52f4SChris Mason &root->root_key, 7850f7d52f4SChris Mason &root->root_item); 78654aa1f4dSChris Mason if (err) 78754aa1f4dSChris Mason break; 7880f7d52f4SChris Mason } 7899f3a7427SChris Mason } 79054aa1f4dSChris Mason return err; 7910f7d52f4SChris Mason } 7920f7d52f4SChris Mason 793d352ac68SChris Mason /* 794d352ac68SChris Mason * defrag a given btree. If cacheonly == 1, this won't read from the disk, 795d352ac68SChris Mason * otherwise every leaf in the btree is read and defragged. 796d352ac68SChris Mason */ 797e9d0b13bSChris Mason int btrfs_defrag_root(struct btrfs_root *root, int cacheonly) 798e9d0b13bSChris Mason { 799e9d0b13bSChris Mason struct btrfs_fs_info *info = root->fs_info; 800e9d0b13bSChris Mason struct btrfs_trans_handle *trans; 8018929ecfaSYan, Zheng int ret; 802d3c2fdcfSChris Mason unsigned long nr; 803e9d0b13bSChris Mason 8048929ecfaSYan, Zheng if (xchg(&root->defrag_running, 1)) 805e9d0b13bSChris Mason return 0; 8068929ecfaSYan, Zheng 8076b80053dSChris Mason while (1) { 8088929ecfaSYan, Zheng trans = btrfs_start_transaction(root, 0); 8098929ecfaSYan, Zheng if (IS_ERR(trans)) 8108929ecfaSYan, Zheng return PTR_ERR(trans); 8118929ecfaSYan, Zheng 812e9d0b13bSChris Mason ret = btrfs_defrag_leaves(trans, root, cacheonly); 8138929ecfaSYan, Zheng 814d3c2fdcfSChris Mason nr = trans->blocks_used; 815e9d0b13bSChris Mason btrfs_end_transaction(trans, root); 816d3c2fdcfSChris Mason btrfs_btree_balance_dirty(info->tree_root, nr); 817e9d0b13bSChris Mason cond_resched(); 818e9d0b13bSChris Mason 8193f157a2fSChris Mason if (root->fs_info->closing || ret != -EAGAIN) 820e9d0b13bSChris Mason break; 821e9d0b13bSChris Mason } 822e9d0b13bSChris Mason root->defrag_running = 0; 8238929ecfaSYan, Zheng return ret; 824e9d0b13bSChris Mason } 825e9d0b13bSChris Mason 8262c47e605SYan Zheng #if 0 827d352ac68SChris Mason /* 828b7ec40d7SChris Mason * when dropping snapshots, we generate a ton of delayed refs, and it makes 829b7ec40d7SChris Mason * sense not to join the transaction while it is trying to flush the current 830b7ec40d7SChris Mason * queue of delayed refs out. 831b7ec40d7SChris Mason * 832b7ec40d7SChris Mason * This is used by the drop snapshot code only 833b7ec40d7SChris Mason */ 834b7ec40d7SChris Mason static noinline int wait_transaction_pre_flush(struct btrfs_fs_info *info) 835b7ec40d7SChris Mason { 836b7ec40d7SChris Mason DEFINE_WAIT(wait); 837b7ec40d7SChris Mason 838b7ec40d7SChris Mason mutex_lock(&info->trans_mutex); 839b7ec40d7SChris Mason while (info->running_transaction && 840b7ec40d7SChris Mason info->running_transaction->delayed_refs.flushing) { 841b7ec40d7SChris Mason prepare_to_wait(&info->transaction_wait, &wait, 842b7ec40d7SChris Mason TASK_UNINTERRUPTIBLE); 843b7ec40d7SChris Mason mutex_unlock(&info->trans_mutex); 84459bc5c75SChris Mason 845b7ec40d7SChris Mason schedule(); 84659bc5c75SChris Mason 847b7ec40d7SChris Mason mutex_lock(&info->trans_mutex); 848b7ec40d7SChris Mason finish_wait(&info->transaction_wait, &wait); 849b7ec40d7SChris Mason } 850b7ec40d7SChris Mason mutex_unlock(&info->trans_mutex); 851b7ec40d7SChris Mason return 0; 852b7ec40d7SChris Mason } 853b7ec40d7SChris Mason 854b7ec40d7SChris Mason /* 855d352ac68SChris Mason * Given a list of roots that need to be deleted, call btrfs_drop_snapshot on 856d352ac68SChris Mason * all of them 857d352ac68SChris Mason */ 8585d4f98a2SYan Zheng int btrfs_drop_dead_root(struct btrfs_root *root) 8590f7d52f4SChris Mason { 8600f7d52f4SChris Mason struct btrfs_trans_handle *trans; 8615d4f98a2SYan Zheng struct btrfs_root *tree_root = root->fs_info->tree_root; 862d3c2fdcfSChris Mason unsigned long nr; 8635d4f98a2SYan Zheng int ret; 86458176a96SJosef Bacik 8659f3a7427SChris Mason while (1) { 866b7ec40d7SChris Mason /* 867b7ec40d7SChris Mason * we don't want to jump in and create a bunch of 868b7ec40d7SChris Mason * delayed refs if the transaction is starting to close 869b7ec40d7SChris Mason */ 870b7ec40d7SChris Mason wait_transaction_pre_flush(tree_root->fs_info); 8710f7d52f4SChris Mason trans = btrfs_start_transaction(tree_root, 1); 872b7ec40d7SChris Mason 873b7ec40d7SChris Mason /* 874b7ec40d7SChris Mason * we've joined a transaction, make sure it isn't 875b7ec40d7SChris Mason * closing right now 876b7ec40d7SChris Mason */ 877b7ec40d7SChris Mason if (trans->transaction->delayed_refs.flushing) { 878b7ec40d7SChris Mason btrfs_end_transaction(trans, tree_root); 879b7ec40d7SChris Mason continue; 880b7ec40d7SChris Mason } 881b7ec40d7SChris Mason 8825d4f98a2SYan Zheng ret = btrfs_drop_snapshot(trans, root); 883d397712bSChris Mason if (ret != -EAGAIN) 8849f3a7427SChris Mason break; 88558176a96SJosef Bacik 8865d4f98a2SYan Zheng ret = btrfs_update_root(trans, tree_root, 8875d4f98a2SYan Zheng &root->root_key, 8885d4f98a2SYan Zheng &root->root_item); 8895d4f98a2SYan Zheng if (ret) 89054aa1f4dSChris Mason break; 891bcc63abbSYan 892d3c2fdcfSChris Mason nr = trans->blocks_used; 8930f7d52f4SChris Mason ret = btrfs_end_transaction(trans, tree_root); 8940f7d52f4SChris Mason BUG_ON(ret); 8955eda7b5eSChris Mason 896d3c2fdcfSChris Mason btrfs_btree_balance_dirty(tree_root, nr); 8974dc11904SChris Mason cond_resched(); 8980f7d52f4SChris Mason } 8995d4f98a2SYan Zheng BUG_ON(ret); 9005d4f98a2SYan Zheng 9015d4f98a2SYan Zheng ret = btrfs_del_root(trans, tree_root, &root->root_key); 9025d4f98a2SYan Zheng BUG_ON(ret); 9035d4f98a2SYan Zheng 9045d4f98a2SYan Zheng nr = trans->blocks_used; 9055d4f98a2SYan Zheng ret = btrfs_end_transaction(trans, tree_root); 9065d4f98a2SYan Zheng BUG_ON(ret); 9075d4f98a2SYan Zheng 9085d4f98a2SYan Zheng free_extent_buffer(root->node); 9095d4f98a2SYan Zheng free_extent_buffer(root->commit_root); 9105d4f98a2SYan Zheng kfree(root); 9115d4f98a2SYan Zheng 9125d4f98a2SYan Zheng btrfs_btree_balance_dirty(tree_root, nr); 91354aa1f4dSChris Mason return ret; 9140f7d52f4SChris Mason } 9152c47e605SYan Zheng #endif 9160f7d52f4SChris Mason 917d352ac68SChris Mason /* 918d352ac68SChris Mason * new snapshots need to be created at a very specific time in the 919d352ac68SChris Mason * transaction commit. This does the actual creation 920d352ac68SChris Mason */ 92180b6794dSChris Mason static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans, 9223063d29fSChris Mason struct btrfs_fs_info *fs_info, 9233063d29fSChris Mason struct btrfs_pending_snapshot *pending) 9243063d29fSChris Mason { 9253063d29fSChris Mason struct btrfs_key key; 92680b6794dSChris Mason struct btrfs_root_item *new_root_item; 9273063d29fSChris Mason struct btrfs_root *tree_root = fs_info->tree_root; 9283063d29fSChris Mason struct btrfs_root *root = pending->root; 9296bdb72deSSage Weil struct btrfs_root *parent_root; 9306bdb72deSSage Weil struct inode *parent_inode; 9316a912213SJosef Bacik struct dentry *parent; 932a22285a6SYan, Zheng struct dentry *dentry; 9333063d29fSChris Mason struct extent_buffer *tmp; 934925baeddSChris Mason struct extent_buffer *old; 9353063d29fSChris Mason int ret; 936d68fc57bSYan, Zheng u64 to_reserve = 0; 9376bdb72deSSage Weil u64 index = 0; 938a22285a6SYan, Zheng u64 objectid; 939b83cc969SLi Zefan u64 root_flags; 9403063d29fSChris Mason 94180b6794dSChris Mason new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS); 94280b6794dSChris Mason if (!new_root_item) { 943a22285a6SYan, Zheng pending->error = -ENOMEM; 94480b6794dSChris Mason goto fail; 94580b6794dSChris Mason } 946a22285a6SYan, Zheng 9473063d29fSChris Mason ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid); 948a22285a6SYan, Zheng if (ret) { 949a22285a6SYan, Zheng pending->error = ret; 9503063d29fSChris Mason goto fail; 951a22285a6SYan, Zheng } 9523063d29fSChris Mason 9533fd0a558SYan, Zheng btrfs_reloc_pre_snapshot(trans, pending, &to_reserve); 954d68fc57bSYan, Zheng btrfs_orphan_pre_snapshot(trans, pending, &to_reserve); 955d68fc57bSYan, Zheng 956d68fc57bSYan, Zheng if (to_reserve > 0) { 957d68fc57bSYan, Zheng ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv, 9588bb8ab2eSJosef Bacik to_reserve); 959d68fc57bSYan, Zheng if (ret) { 960d68fc57bSYan, Zheng pending->error = ret; 961d68fc57bSYan, Zheng goto fail; 962d68fc57bSYan, Zheng } 963d68fc57bSYan, Zheng } 964d68fc57bSYan, Zheng 9653063d29fSChris Mason key.objectid = objectid; 966a22285a6SYan, Zheng key.offset = (u64)-1; 967a22285a6SYan, Zheng key.type = BTRFS_ROOT_ITEM_KEY; 9683063d29fSChris Mason 969a22285a6SYan, Zheng trans->block_rsv = &pending->block_rsv; 9706bdb72deSSage Weil 971a22285a6SYan, Zheng dentry = pending->dentry; 9726a912213SJosef Bacik parent = dget_parent(dentry); 9736a912213SJosef Bacik parent_inode = parent->d_inode; 974a22285a6SYan, Zheng parent_root = BTRFS_I(parent_inode)->root; 9756bdb72deSSage Weil record_root_in_trans(trans, parent_root); 976a22285a6SYan, Zheng 9776bdb72deSSage Weil /* 9786bdb72deSSage Weil * insert the directory item 9796bdb72deSSage Weil */ 9806bdb72deSSage Weil ret = btrfs_set_inode_index(parent_inode, &index); 9816bdb72deSSage Weil BUG_ON(ret); 9826bdb72deSSage Weil ret = btrfs_insert_dir_item(trans, parent_root, 983a22285a6SYan, Zheng dentry->d_name.name, dentry->d_name.len, 984a22285a6SYan, Zheng parent_inode->i_ino, &key, 985a22285a6SYan, Zheng BTRFS_FT_DIR, index); 9866bdb72deSSage Weil BUG_ON(ret); 9876bdb72deSSage Weil 988a22285a6SYan, Zheng btrfs_i_size_write(parent_inode, parent_inode->i_size + 989a22285a6SYan, Zheng dentry->d_name.len * 2); 9906bdb72deSSage Weil ret = btrfs_update_inode(trans, parent_root, parent_inode); 9916bdb72deSSage Weil BUG_ON(ret); 9926bdb72deSSage Weil 9936bdb72deSSage Weil record_root_in_trans(trans, root); 9946bdb72deSSage Weil btrfs_set_root_last_snapshot(&root->root_item, trans->transid); 9956bdb72deSSage Weil memcpy(new_root_item, &root->root_item, sizeof(*new_root_item)); 99608fe4db1SLi Zefan btrfs_check_and_init_root_item(new_root_item); 9976bdb72deSSage Weil 998b83cc969SLi Zefan root_flags = btrfs_root_flags(new_root_item); 999b83cc969SLi Zefan if (pending->readonly) 1000b83cc969SLi Zefan root_flags |= BTRFS_ROOT_SUBVOL_RDONLY; 1001b83cc969SLi Zefan else 1002b83cc969SLi Zefan root_flags &= ~BTRFS_ROOT_SUBVOL_RDONLY; 1003b83cc969SLi Zefan btrfs_set_root_flags(new_root_item, root_flags); 1004b83cc969SLi Zefan 1005925baeddSChris Mason old = btrfs_lock_root_node(root); 10069fa8cfe7SChris Mason btrfs_cow_block(trans, root, old, NULL, 0, &old); 10075d4f98a2SYan Zheng btrfs_set_lock_blocking(old); 10083063d29fSChris Mason 1009925baeddSChris Mason btrfs_copy_root(trans, root, old, &tmp, objectid); 1010925baeddSChris Mason btrfs_tree_unlock(old); 1011925baeddSChris Mason free_extent_buffer(old); 10123063d29fSChris Mason 10135d4f98a2SYan Zheng btrfs_set_root_node(new_root_item, tmp); 1014a22285a6SYan, Zheng /* record when the snapshot was created in key.offset */ 1015a22285a6SYan, Zheng key.offset = trans->transid; 1016a22285a6SYan, Zheng ret = btrfs_insert_root(trans, tree_root, &key, new_root_item); 1017925baeddSChris Mason btrfs_tree_unlock(tmp); 10183063d29fSChris Mason free_extent_buffer(tmp); 10190660b5afSChris Mason BUG_ON(ret); 10200660b5afSChris Mason 1021a22285a6SYan, Zheng /* 1022a22285a6SYan, Zheng * insert root back/forward references 1023a22285a6SYan, Zheng */ 1024a22285a6SYan, Zheng ret = btrfs_add_root_ref(trans, tree_root, objectid, 1025a22285a6SYan, Zheng parent_root->root_key.objectid, 1026a22285a6SYan, Zheng parent_inode->i_ino, index, 1027a22285a6SYan, Zheng dentry->d_name.name, dentry->d_name.len); 1028a22285a6SYan, Zheng BUG_ON(ret); 10296a912213SJosef Bacik dput(parent); 1030a22285a6SYan, Zheng 1031a22285a6SYan, Zheng key.offset = (u64)-1; 1032a22285a6SYan, Zheng pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key); 1033a22285a6SYan, Zheng BUG_ON(IS_ERR(pending->snap)); 1034d68fc57bSYan, Zheng 10353fd0a558SYan, Zheng btrfs_reloc_post_snapshot(trans, pending); 1036d68fc57bSYan, Zheng btrfs_orphan_post_snapshot(trans, pending); 10373063d29fSChris Mason fail: 10386bdb72deSSage Weil kfree(new_root_item); 1039a22285a6SYan, Zheng btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1); 1040a22285a6SYan, Zheng return 0; 10413063d29fSChris Mason } 10423063d29fSChris Mason 1043d352ac68SChris Mason /* 1044d352ac68SChris Mason * create all the snapshots we've scheduled for creation 1045d352ac68SChris Mason */ 104680b6794dSChris Mason static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans, 10473063d29fSChris Mason struct btrfs_fs_info *fs_info) 10483063d29fSChris Mason { 10493063d29fSChris Mason struct btrfs_pending_snapshot *pending; 10503063d29fSChris Mason struct list_head *head = &trans->transaction->pending_snapshots; 10513de4586cSChris Mason int ret; 10523de4586cSChris Mason 1053c6e30871SQinghuang Feng list_for_each_entry(pending, head, list) { 10543de4586cSChris Mason ret = create_pending_snapshot(trans, fs_info, pending); 10553de4586cSChris Mason BUG_ON(ret); 10563de4586cSChris Mason } 10573de4586cSChris Mason return 0; 10583de4586cSChris Mason } 10593de4586cSChris Mason 10605d4f98a2SYan Zheng static void update_super_roots(struct btrfs_root *root) 10615d4f98a2SYan Zheng { 10625d4f98a2SYan Zheng struct btrfs_root_item *root_item; 10635d4f98a2SYan Zheng struct btrfs_super_block *super; 10645d4f98a2SYan Zheng 10655d4f98a2SYan Zheng super = &root->fs_info->super_copy; 10665d4f98a2SYan Zheng 10675d4f98a2SYan Zheng root_item = &root->fs_info->chunk_root->root_item; 10685d4f98a2SYan Zheng super->chunk_root = root_item->bytenr; 10695d4f98a2SYan Zheng super->chunk_root_generation = root_item->generation; 10705d4f98a2SYan Zheng super->chunk_root_level = root_item->level; 10715d4f98a2SYan Zheng 10725d4f98a2SYan Zheng root_item = &root->fs_info->tree_root->root_item; 10735d4f98a2SYan Zheng super->root = root_item->bytenr; 10745d4f98a2SYan Zheng super->generation = root_item->generation; 10755d4f98a2SYan Zheng super->root_level = root_item->level; 10760af3d00bSJosef Bacik if (super->cache_generation != 0 || btrfs_test_opt(root, SPACE_CACHE)) 10770af3d00bSJosef Bacik super->cache_generation = root_item->generation; 10785d4f98a2SYan Zheng } 10795d4f98a2SYan Zheng 1080f36f3042SChris Mason int btrfs_transaction_in_commit(struct btrfs_fs_info *info) 1081f36f3042SChris Mason { 1082f36f3042SChris Mason int ret = 0; 1083f36f3042SChris Mason spin_lock(&info->new_trans_lock); 1084f36f3042SChris Mason if (info->running_transaction) 1085f36f3042SChris Mason ret = info->running_transaction->in_commit; 1086f36f3042SChris Mason spin_unlock(&info->new_trans_lock); 1087f36f3042SChris Mason return ret; 1088f36f3042SChris Mason } 1089f36f3042SChris Mason 10908929ecfaSYan, Zheng int btrfs_transaction_blocked(struct btrfs_fs_info *info) 10918929ecfaSYan, Zheng { 10928929ecfaSYan, Zheng int ret = 0; 10938929ecfaSYan, Zheng spin_lock(&info->new_trans_lock); 10948929ecfaSYan, Zheng if (info->running_transaction) 10958929ecfaSYan, Zheng ret = info->running_transaction->blocked; 10968929ecfaSYan, Zheng spin_unlock(&info->new_trans_lock); 10978929ecfaSYan, Zheng return ret; 10988929ecfaSYan, Zheng } 10998929ecfaSYan, Zheng 1100bb9c12c9SSage Weil /* 1101bb9c12c9SSage Weil * wait for the current transaction commit to start and block subsequent 1102bb9c12c9SSage Weil * transaction joins 1103bb9c12c9SSage Weil */ 1104bb9c12c9SSage Weil static void wait_current_trans_commit_start(struct btrfs_root *root, 1105bb9c12c9SSage Weil struct btrfs_transaction *trans) 1106bb9c12c9SSage Weil { 1107bb9c12c9SSage Weil DEFINE_WAIT(wait); 1108bb9c12c9SSage Weil 1109bb9c12c9SSage Weil if (trans->in_commit) 1110bb9c12c9SSage Weil return; 1111bb9c12c9SSage Weil 1112bb9c12c9SSage Weil while (1) { 1113bb9c12c9SSage Weil prepare_to_wait(&root->fs_info->transaction_blocked_wait, &wait, 1114bb9c12c9SSage Weil TASK_UNINTERRUPTIBLE); 1115bb9c12c9SSage Weil if (trans->in_commit) { 1116bb9c12c9SSage Weil finish_wait(&root->fs_info->transaction_blocked_wait, 1117bb9c12c9SSage Weil &wait); 1118bb9c12c9SSage Weil break; 1119bb9c12c9SSage Weil } 1120bb9c12c9SSage Weil mutex_unlock(&root->fs_info->trans_mutex); 1121bb9c12c9SSage Weil schedule(); 1122bb9c12c9SSage Weil mutex_lock(&root->fs_info->trans_mutex); 1123bb9c12c9SSage Weil finish_wait(&root->fs_info->transaction_blocked_wait, &wait); 1124bb9c12c9SSage Weil } 1125bb9c12c9SSage Weil } 1126bb9c12c9SSage Weil 1127bb9c12c9SSage Weil /* 1128bb9c12c9SSage Weil * wait for the current transaction to start and then become unblocked. 1129bb9c12c9SSage Weil * caller holds ref. 1130bb9c12c9SSage Weil */ 1131bb9c12c9SSage Weil static void wait_current_trans_commit_start_and_unblock(struct btrfs_root *root, 1132bb9c12c9SSage Weil struct btrfs_transaction *trans) 1133bb9c12c9SSage Weil { 1134bb9c12c9SSage Weil DEFINE_WAIT(wait); 1135bb9c12c9SSage Weil 1136bb9c12c9SSage Weil if (trans->commit_done || (trans->in_commit && !trans->blocked)) 1137bb9c12c9SSage Weil return; 1138bb9c12c9SSage Weil 1139bb9c12c9SSage Weil while (1) { 1140bb9c12c9SSage Weil prepare_to_wait(&root->fs_info->transaction_wait, &wait, 1141bb9c12c9SSage Weil TASK_UNINTERRUPTIBLE); 1142bb9c12c9SSage Weil if (trans->commit_done || 1143bb9c12c9SSage Weil (trans->in_commit && !trans->blocked)) { 1144bb9c12c9SSage Weil finish_wait(&root->fs_info->transaction_wait, 1145bb9c12c9SSage Weil &wait); 1146bb9c12c9SSage Weil break; 1147bb9c12c9SSage Weil } 1148bb9c12c9SSage Weil mutex_unlock(&root->fs_info->trans_mutex); 1149bb9c12c9SSage Weil schedule(); 1150bb9c12c9SSage Weil mutex_lock(&root->fs_info->trans_mutex); 1151bb9c12c9SSage Weil finish_wait(&root->fs_info->transaction_wait, 1152bb9c12c9SSage Weil &wait); 1153bb9c12c9SSage Weil } 1154bb9c12c9SSage Weil } 1155bb9c12c9SSage Weil 1156bb9c12c9SSage Weil /* 1157bb9c12c9SSage Weil * commit transactions asynchronously. once btrfs_commit_transaction_async 1158bb9c12c9SSage Weil * returns, any subsequent transaction will not be allowed to join. 1159bb9c12c9SSage Weil */ 1160bb9c12c9SSage Weil struct btrfs_async_commit { 1161bb9c12c9SSage Weil struct btrfs_trans_handle *newtrans; 1162bb9c12c9SSage Weil struct btrfs_root *root; 1163bb9c12c9SSage Weil struct delayed_work work; 1164bb9c12c9SSage Weil }; 1165bb9c12c9SSage Weil 1166bb9c12c9SSage Weil static void do_async_commit(struct work_struct *work) 1167bb9c12c9SSage Weil { 1168bb9c12c9SSage Weil struct btrfs_async_commit *ac = 1169bb9c12c9SSage Weil container_of(work, struct btrfs_async_commit, work.work); 1170bb9c12c9SSage Weil 1171bb9c12c9SSage Weil btrfs_commit_transaction(ac->newtrans, ac->root); 1172bb9c12c9SSage Weil kfree(ac); 1173bb9c12c9SSage Weil } 1174bb9c12c9SSage Weil 1175bb9c12c9SSage Weil int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans, 1176bb9c12c9SSage Weil struct btrfs_root *root, 1177bb9c12c9SSage Weil int wait_for_unblock) 1178bb9c12c9SSage Weil { 1179bb9c12c9SSage Weil struct btrfs_async_commit *ac; 1180bb9c12c9SSage Weil struct btrfs_transaction *cur_trans; 1181bb9c12c9SSage Weil 1182bb9c12c9SSage Weil ac = kmalloc(sizeof(*ac), GFP_NOFS); 1183db5b493aSTsutomu Itoh if (!ac) 1184db5b493aSTsutomu Itoh return -ENOMEM; 1185bb9c12c9SSage Weil 1186bb9c12c9SSage Weil INIT_DELAYED_WORK(&ac->work, do_async_commit); 1187bb9c12c9SSage Weil ac->root = root; 11887a7eaa40SJosef Bacik ac->newtrans = btrfs_join_transaction(root); 11893612b495STsutomu Itoh if (IS_ERR(ac->newtrans)) { 11903612b495STsutomu Itoh int err = PTR_ERR(ac->newtrans); 11913612b495STsutomu Itoh kfree(ac); 11923612b495STsutomu Itoh return err; 11933612b495STsutomu Itoh } 1194bb9c12c9SSage Weil 1195bb9c12c9SSage Weil /* take transaction reference */ 1196bb9c12c9SSage Weil mutex_lock(&root->fs_info->trans_mutex); 1197bb9c12c9SSage Weil cur_trans = trans->transaction; 119813c5a93eSJosef Bacik atomic_inc(&cur_trans->use_count); 1199bb9c12c9SSage Weil mutex_unlock(&root->fs_info->trans_mutex); 1200bb9c12c9SSage Weil 1201bb9c12c9SSage Weil btrfs_end_transaction(trans, root); 1202bb9c12c9SSage Weil schedule_delayed_work(&ac->work, 0); 1203bb9c12c9SSage Weil 1204bb9c12c9SSage Weil /* wait for transaction to start and unblock */ 1205bb9c12c9SSage Weil mutex_lock(&root->fs_info->trans_mutex); 1206bb9c12c9SSage Weil if (wait_for_unblock) 1207bb9c12c9SSage Weil wait_current_trans_commit_start_and_unblock(root, cur_trans); 1208bb9c12c9SSage Weil else 1209bb9c12c9SSage Weil wait_current_trans_commit_start(root, cur_trans); 1210bb9c12c9SSage Weil put_transaction(cur_trans); 1211bb9c12c9SSage Weil mutex_unlock(&root->fs_info->trans_mutex); 1212bb9c12c9SSage Weil 1213bb9c12c9SSage Weil return 0; 1214bb9c12c9SSage Weil } 1215bb9c12c9SSage Weil 1216bb9c12c9SSage Weil /* 1217bb9c12c9SSage Weil * btrfs_transaction state sequence: 1218bb9c12c9SSage Weil * in_commit = 0, blocked = 0 (initial) 1219bb9c12c9SSage Weil * in_commit = 1, blocked = 1 1220bb9c12c9SSage Weil * blocked = 0 1221bb9c12c9SSage Weil * commit_done = 1 1222bb9c12c9SSage Weil */ 122379154b1bSChris Mason int btrfs_commit_transaction(struct btrfs_trans_handle *trans, 122479154b1bSChris Mason struct btrfs_root *root) 122579154b1bSChris Mason { 122615ee9bc7SJosef Bacik unsigned long joined = 0; 122779154b1bSChris Mason struct btrfs_transaction *cur_trans; 12288fd17795SChris Mason struct btrfs_transaction *prev_trans = NULL; 122979154b1bSChris Mason DEFINE_WAIT(wait); 123015ee9bc7SJosef Bacik int ret; 123189573b9cSChris Mason int should_grow = 0; 123289573b9cSChris Mason unsigned long now = get_seconds(); 1233dccae999SSage Weil int flush_on_commit = btrfs_test_opt(root, FLUSHONCOMMIT); 123479154b1bSChris Mason 12355a3f23d5SChris Mason btrfs_run_ordered_operations(root, 0); 12365a3f23d5SChris Mason 123756bec294SChris Mason /* make a pass through all the delayed refs we have so far 123856bec294SChris Mason * any runnings procs may add more while we are here 123956bec294SChris Mason */ 124056bec294SChris Mason ret = btrfs_run_delayed_refs(trans, root, 0); 124156bec294SChris Mason BUG_ON(ret); 124256bec294SChris Mason 1243a22285a6SYan, Zheng btrfs_trans_release_metadata(trans, root); 1244a22285a6SYan, Zheng 1245b7ec40d7SChris Mason cur_trans = trans->transaction; 124656bec294SChris Mason /* 124756bec294SChris Mason * set the flushing flag so procs in this transaction have to 124856bec294SChris Mason * start sending their work down. 124956bec294SChris Mason */ 1250b7ec40d7SChris Mason cur_trans->delayed_refs.flushing = 1; 125156bec294SChris Mason 1252c3e69d58SChris Mason ret = btrfs_run_delayed_refs(trans, root, 0); 125356bec294SChris Mason BUG_ON(ret); 125456bec294SChris Mason 125579154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 1256b7ec40d7SChris Mason if (cur_trans->in_commit) { 125713c5a93eSJosef Bacik atomic_inc(&cur_trans->use_count); 1258ccd467d6SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 125979154b1bSChris Mason btrfs_end_transaction(trans, root); 1260ccd467d6SChris Mason 126179154b1bSChris Mason ret = wait_for_commit(root, cur_trans); 126279154b1bSChris Mason BUG_ON(ret); 126315ee9bc7SJosef Bacik 126415ee9bc7SJosef Bacik mutex_lock(&root->fs_info->trans_mutex); 126579154b1bSChris Mason put_transaction(cur_trans); 126615ee9bc7SJosef Bacik mutex_unlock(&root->fs_info->trans_mutex); 126715ee9bc7SJosef Bacik 126879154b1bSChris Mason return 0; 126979154b1bSChris Mason } 12704313b399SChris Mason 12712c90e5d6SChris Mason trans->transaction->in_commit = 1; 1272f9295749SChris Mason trans->transaction->blocked = 1; 1273bb9c12c9SSage Weil wake_up(&root->fs_info->transaction_blocked_wait); 1274bb9c12c9SSage Weil 1275ccd467d6SChris Mason if (cur_trans->list.prev != &root->fs_info->trans_list) { 1276ccd467d6SChris Mason prev_trans = list_entry(cur_trans->list.prev, 1277ccd467d6SChris Mason struct btrfs_transaction, list); 1278ccd467d6SChris Mason if (!prev_trans->commit_done) { 127913c5a93eSJosef Bacik atomic_inc(&prev_trans->use_count); 1280ccd467d6SChris Mason mutex_unlock(&root->fs_info->trans_mutex); 1281ccd467d6SChris Mason 1282ccd467d6SChris Mason wait_for_commit(root, prev_trans); 1283ccd467d6SChris Mason 1284ccd467d6SChris Mason mutex_lock(&root->fs_info->trans_mutex); 128515ee9bc7SJosef Bacik put_transaction(prev_trans); 1286ccd467d6SChris Mason } 1287ccd467d6SChris Mason } 128815ee9bc7SJosef Bacik 128989573b9cSChris Mason if (now < cur_trans->start_time || now - cur_trans->start_time < 1) 129089573b9cSChris Mason should_grow = 1; 129189573b9cSChris Mason 129215ee9bc7SJosef Bacik do { 12937ea394f1SYan Zheng int snap_pending = 0; 129415ee9bc7SJosef Bacik joined = cur_trans->num_joined; 12957ea394f1SYan Zheng if (!list_empty(&trans->transaction->pending_snapshots)) 12967ea394f1SYan Zheng snap_pending = 1; 12977ea394f1SYan Zheng 12982c90e5d6SChris Mason WARN_ON(cur_trans != trans->transaction); 129979154b1bSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 130015ee9bc7SJosef Bacik 13010bdb1db2SSage Weil if (flush_on_commit || snap_pending) { 130224bbcf04SYan, Zheng btrfs_start_delalloc_inodes(root, 1); 130324bbcf04SYan, Zheng ret = btrfs_wait_ordered_extents(root, 0, 1); 1304ebecd3d9SSage Weil BUG_ON(ret); 13057ea394f1SYan Zheng } 13067ea394f1SYan Zheng 13075a3f23d5SChris Mason /* 13085a3f23d5SChris Mason * rename don't use btrfs_join_transaction, so, once we 13095a3f23d5SChris Mason * set the transaction to blocked above, we aren't going 13105a3f23d5SChris Mason * to get any new ordered operations. We can safely run 13115a3f23d5SChris Mason * it here and no for sure that nothing new will be added 13125a3f23d5SChris Mason * to the list 13135a3f23d5SChris Mason */ 13145a3f23d5SChris Mason btrfs_run_ordered_operations(root, 1); 13155a3f23d5SChris Mason 1316ed3b3d31SChris Mason prepare_to_wait(&cur_trans->writer_wait, &wait, 1317ed3b3d31SChris Mason TASK_UNINTERRUPTIBLE); 1318ed3b3d31SChris Mason 131989573b9cSChris Mason smp_mb(); 132013c5a93eSJosef Bacik if (atomic_read(&cur_trans->num_writers) > 1) 132199d16cbcSSage Weil schedule_timeout(MAX_SCHEDULE_TIMEOUT); 132299d16cbcSSage Weil else if (should_grow) 132399d16cbcSSage Weil schedule_timeout(1); 132415ee9bc7SJosef Bacik 132579154b1bSChris Mason mutex_lock(&root->fs_info->trans_mutex); 132615ee9bc7SJosef Bacik finish_wait(&cur_trans->writer_wait, &wait); 132713c5a93eSJosef Bacik } while (atomic_read(&cur_trans->num_writers) > 1 || 132889573b9cSChris Mason (should_grow && cur_trans->num_joined != joined)); 132915ee9bc7SJosef Bacik 13303063d29fSChris Mason ret = create_pending_snapshots(trans, root->fs_info); 13313063d29fSChris Mason BUG_ON(ret); 13323063d29fSChris Mason 133356bec294SChris Mason ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1); 133456bec294SChris Mason BUG_ON(ret); 133556bec294SChris Mason 13362c90e5d6SChris Mason WARN_ON(cur_trans != trans->transaction); 1337dc17ff8fSChris Mason 1338e02119d5SChris Mason /* btrfs_commit_tree_roots is responsible for getting the 1339e02119d5SChris Mason * various roots consistent with each other. Every pointer 1340e02119d5SChris Mason * in the tree of tree roots has to point to the most up to date 1341e02119d5SChris Mason * root for every subvolume and other tree. So, we have to keep 1342e02119d5SChris Mason * the tree logging code from jumping in and changing any 1343e02119d5SChris Mason * of the trees. 1344e02119d5SChris Mason * 1345e02119d5SChris Mason * At this point in the commit, there can't be any tree-log 1346e02119d5SChris Mason * writers, but a little lower down we drop the trans mutex 1347e02119d5SChris Mason * and let new people in. By holding the tree_log_mutex 1348e02119d5SChris Mason * from now until after the super is written, we avoid races 1349e02119d5SChris Mason * with the tree-log code. 1350e02119d5SChris Mason */ 1351e02119d5SChris Mason mutex_lock(&root->fs_info->tree_log_mutex); 13521a40e23bSZheng Yan 13535d4f98a2SYan Zheng ret = commit_fs_roots(trans, root); 135454aa1f4dSChris Mason BUG_ON(ret); 135554aa1f4dSChris Mason 13565d4f98a2SYan Zheng /* commit_fs_roots gets rid of all the tree log roots, it is now 1357e02119d5SChris Mason * safe to free the root of tree log roots 1358e02119d5SChris Mason */ 1359e02119d5SChris Mason btrfs_free_log_root_tree(trans, root->fs_info); 1360e02119d5SChris Mason 13615d4f98a2SYan Zheng ret = commit_cowonly_roots(trans, root); 136279154b1bSChris Mason BUG_ON(ret); 136354aa1f4dSChris Mason 136411833d66SYan Zheng btrfs_prepare_extent_commit(trans, root); 136511833d66SYan Zheng 136678fae27eSChris Mason cur_trans = root->fs_info->running_transaction; 1367cee36a03SChris Mason spin_lock(&root->fs_info->new_trans_lock); 136878fae27eSChris Mason root->fs_info->running_transaction = NULL; 1369cee36a03SChris Mason spin_unlock(&root->fs_info->new_trans_lock); 13705f39d397SChris Mason 13715d4f98a2SYan Zheng btrfs_set_root_node(&root->fs_info->tree_root->root_item, 13725d4f98a2SYan Zheng root->fs_info->tree_root->node); 1373817d52f8SJosef Bacik switch_commit_root(root->fs_info->tree_root); 13745d4f98a2SYan Zheng 13755d4f98a2SYan Zheng btrfs_set_root_node(&root->fs_info->chunk_root->root_item, 13765d4f98a2SYan Zheng root->fs_info->chunk_root->node); 1377817d52f8SJosef Bacik switch_commit_root(root->fs_info->chunk_root); 13785d4f98a2SYan Zheng 13795d4f98a2SYan Zheng update_super_roots(root); 1380e02119d5SChris Mason 1381e02119d5SChris Mason if (!root->fs_info->log_root_recovering) { 1382e02119d5SChris Mason btrfs_set_super_log_root(&root->fs_info->super_copy, 0); 1383e02119d5SChris Mason btrfs_set_super_log_root_level(&root->fs_info->super_copy, 0); 1384e02119d5SChris Mason } 1385e02119d5SChris Mason 1386a061fc8dSChris Mason memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy, 13874b52dff6SChris Mason sizeof(root->fs_info->super_copy)); 1388ccd467d6SChris Mason 1389f9295749SChris Mason trans->transaction->blocked = 0; 1390b7ec40d7SChris Mason 1391f9295749SChris Mason wake_up(&root->fs_info->transaction_wait); 1392e6dcd2dcSChris Mason 139378fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 139479154b1bSChris Mason ret = btrfs_write_and_wait_transaction(trans, root); 139579154b1bSChris Mason BUG_ON(ret); 1396a512bbf8SYan Zheng write_ctree_super(trans, root, 0); 13974313b399SChris Mason 1398e02119d5SChris Mason /* 1399e02119d5SChris Mason * the super is written, we can safely allow the tree-loggers 1400e02119d5SChris Mason * to go about their business 1401e02119d5SChris Mason */ 1402e02119d5SChris Mason mutex_unlock(&root->fs_info->tree_log_mutex); 1403e02119d5SChris Mason 140411833d66SYan Zheng btrfs_finish_extent_commit(trans, root); 14054313b399SChris Mason 14061a40e23bSZheng Yan mutex_lock(&root->fs_info->trans_mutex); 14071a40e23bSZheng Yan 14082c90e5d6SChris Mason cur_trans->commit_done = 1; 1409b7ec40d7SChris Mason 141015ee9bc7SJosef Bacik root->fs_info->last_trans_committed = cur_trans->transid; 1411817d52f8SJosef Bacik 14122c90e5d6SChris Mason wake_up(&cur_trans->commit_wait); 14133de4586cSChris Mason 141413c5a93eSJosef Bacik list_del_init(&cur_trans->list); 141579154b1bSChris Mason put_transaction(cur_trans); 141678fae27eSChris Mason put_transaction(cur_trans); 141758176a96SJosef Bacik 14181abe9b8aSliubo trace_btrfs_transaction_commit(root); 14191abe9b8aSliubo 142078fae27eSChris Mason mutex_unlock(&root->fs_info->trans_mutex); 14213de4586cSChris Mason 14229ed74f2dSJosef Bacik if (current->journal_info == trans) 14239ed74f2dSJosef Bacik current->journal_info = NULL; 14249ed74f2dSJosef Bacik 14252c90e5d6SChris Mason kmem_cache_free(btrfs_trans_handle_cachep, trans); 142624bbcf04SYan, Zheng 142724bbcf04SYan, Zheng if (current != root->fs_info->transaction_kthread) 142824bbcf04SYan, Zheng btrfs_run_delayed_iputs(root); 142924bbcf04SYan, Zheng 143079154b1bSChris Mason return ret; 143179154b1bSChris Mason } 143279154b1bSChris Mason 1433d352ac68SChris Mason /* 1434d352ac68SChris Mason * interface function to delete all the snapshots we have scheduled for deletion 1435d352ac68SChris Mason */ 1436e9d0b13bSChris Mason int btrfs_clean_old_snapshots(struct btrfs_root *root) 1437e9d0b13bSChris Mason { 14385d4f98a2SYan Zheng LIST_HEAD(list); 14395d4f98a2SYan Zheng struct btrfs_fs_info *fs_info = root->fs_info; 1440e9d0b13bSChris Mason 14415d4f98a2SYan Zheng mutex_lock(&fs_info->trans_mutex); 14425d4f98a2SYan Zheng list_splice_init(&fs_info->dead_roots, &list); 14435d4f98a2SYan Zheng mutex_unlock(&fs_info->trans_mutex); 14445d4f98a2SYan Zheng 14455d4f98a2SYan Zheng while (!list_empty(&list)) { 14465d4f98a2SYan Zheng root = list_entry(list.next, struct btrfs_root, root_list); 144776dda93cSYan, Zheng list_del(&root->root_list); 144876dda93cSYan, Zheng 144976dda93cSYan, Zheng if (btrfs_header_backref_rev(root->node) < 145076dda93cSYan, Zheng BTRFS_MIXED_BACKREF_REV) 14513fd0a558SYan, Zheng btrfs_drop_snapshot(root, NULL, 0); 145276dda93cSYan, Zheng else 14533fd0a558SYan, Zheng btrfs_drop_snapshot(root, NULL, 1); 1454e9d0b13bSChris Mason } 1455e9d0b13bSChris Mason return 0; 1456e9d0b13bSChris Mason } 1457