diff options
Diffstat (limited to 'fs/btrfs/tree-log.c')
| -rw-r--r-- | fs/btrfs/tree-log.c | 60 |
1 files changed, 43 insertions, 17 deletions
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 6c47f6ed3e94..6c8297bcfeb7 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -3110,6 +3110,12 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, log->log_transid = root->log_transid; root->log_start_pid = 0; /* + * Update or create log root item under the root's log_mutex to prevent + * races with concurrent log syncs that can lead to failure to update + * log root item because it was not created yet. + */ + ret = update_log_root(trans, log); + /* * IO has been started, blocks of the log tree have WRITTEN flag set * in their headers. new modifications of the log will be written to * new positions. so it's safe to allow log writers to go in. @@ -3128,8 +3134,6 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, mutex_unlock(&log_root_tree->log_mutex); - ret = update_log_root(trans, log); - mutex_lock(&log_root_tree->log_mutex); if (atomic_dec_and_test(&log_root_tree->log_writers)) { /* atomic_dec_and_test implies a barrier */ @@ -3319,6 +3323,30 @@ int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans, } /* + * Check if an inode was logged in the current transaction. We can't always rely + * on an inode's logged_trans value, because it's an in-memory only field and + * therefore not persisted. This means that its value is lost if the inode gets + * evicted and loaded again from disk (in which case it has a value of 0, and + * certainly it is smaller then any possible transaction ID), when that happens + * the full_sync flag is set in the inode's runtime flags, so on that case we + * assume eviction happened and ignore the logged_trans value, assuming the + * worst case, that the inode was logged before in the current transaction. + */ +static bool inode_logged(struct btrfs_trans_handle *trans, + struct btrfs_inode *inode) +{ + if (inode->logged_trans == trans->transid) + return true; + + if (inode->last_trans == trans->transid && + test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags) && + !test_bit(BTRFS_FS_LOG_RECOVERING, &trans->fs_info->flags)) + return true; + + return false; +} + +/* * If both a file and directory are logged, and unlinks or renames are * mixed in, we have a few interesting corners: * @@ -3352,7 +3380,7 @@ int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans, int bytes_del = 0; u64 dir_ino = btrfs_ino(dir); - if (dir->logged_trans < trans->transid) + if (!inode_logged(trans, dir)) return 0; ret = join_running_log_trans(root); @@ -3456,7 +3484,7 @@ int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans, u64 index; int ret; - if (inode->logged_trans < trans->transid) + if (!inode_logged(trans, inode)) return 0; ret = join_running_log_trans(root); @@ -5416,9 +5444,19 @@ log_extents: } } + /* + * Don't update last_log_commit if we logged that an inode exists after + * it was loaded to memory (full_sync bit set). + * This is to prevent data loss when we do a write to the inode, then + * the inode gets evicted after all delalloc was flushed, then we log + * it exists (due to a rename for example) and then fsync it. This last + * fsync would do nothing (not logging the extents previously written). + */ spin_lock(&inode->lock); inode->logged_trans = trans->transid; - inode->last_log_commit = inode->last_sub_trans; + if (inode_only != LOG_INODE_EXISTS || + !test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags)) + inode->last_log_commit = inode->last_sub_trans; spin_unlock(&inode->lock); out_unlock: mutex_unlock(&inode->log_mutex); @@ -5478,7 +5516,6 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans, { int ret = 0; struct dentry *old_parent = NULL; - struct btrfs_inode *orig_inode = inode; /* * for regular files, if its inode is already on disk, we don't @@ -5498,16 +5535,6 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans, } while (1) { - /* - * If we are logging a directory then we start with our inode, - * not our parent's inode, so we need to skip setting the - * logged_trans so that further down in the log code we don't - * think this inode has already been logged. - */ - if (inode != orig_inode) - inode->logged_trans = trans->transid; - smp_mb(); - if (btrfs_must_commit_transaction(trans, inode)) { ret = 1; break; @@ -6384,7 +6411,6 @@ void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans, * if this directory was already logged any new * names for this file/dir will get recorded */ - smp_mb(); if (dir->logged_trans == trans->transid) return; |