diff options
Diffstat (limited to 'fs/btrfs/tree-log.c')
| -rw-r--r-- | fs/btrfs/tree-log.c | 444 |
1 files changed, 365 insertions, 79 deletions
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 9c462fbd60f..fc9b87a7975 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -35,6 +35,49 @@ #define LOG_INODE_EXISTS 1 /* + * directory trouble cases + * + * 1) on rename or unlink, if the inode being unlinked isn't in the fsync + * log, we must force a full commit before doing an fsync of the directory + * where the unlink was done. + * ---> record transid of last unlink/rename per directory + * + * mkdir foo/some_dir + * normal commit + * rename foo/some_dir foo2/some_dir + * mkdir foo/some_dir + * fsync foo/some_dir/some_file + * + * The fsync above will unlink the original some_dir without recording + * it in its new location (foo2). After a crash, some_dir will be gone + * unless the fsync of some_file forces a full commit + * + * 2) we must log any new names for any file or dir that is in the fsync + * log. ---> check inode while renaming/linking. + * + * 2a) we must log any new names for any file or dir during rename + * when the directory they are being removed from was logged. + * ---> check inode and old parent dir during rename + * + * 2a is actually the more important variant. With the extra logging + * a crash might unlink the old name without recreating the new one + * + * 3) after a crash, we must go through any directories with a link count + * of zero and redo the rm -rf + * + * mkdir f1/foo + * normal commit + * rm -rf f1/foo + * fsync(f1) + * + * The directory f1 was fully removed from the FS, but fsync was never + * called on f1, only its parent dir. After a crash the rm -rf must + * be replayed. This must be able to recurse down the entire + * directory tree. The inode link count fixup code takes care of the + * ugly details. + */ + +/* * stages for the tree walking. The first * stage (0) is to only pin down the blocks we find * the second stage (1) is to make sure that all the inodes @@ -47,12 +90,17 @@ #define LOG_WALK_REPLAY_INODES 1 #define LOG_WALK_REPLAY_ALL 2 -static int __btrfs_log_inode(struct btrfs_trans_handle *trans, +static int btrfs_log_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, int inode_only); static int link_to_fixup_dir(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 objectid); +static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_root *log, + struct btrfs_path *path, + u64 dirid, int del_all); /* * tree logging is a special write ahead log used to make sure that @@ -133,10 +181,25 @@ static int join_running_log_trans(struct btrfs_root *root) } /* + * This either makes the current running log transaction wait + * until you call btrfs_end_log_trans() or it makes any future + * log transactions wait until you call btrfs_end_log_trans() + */ +int btrfs_pin_log_trans(struct btrfs_root *root) +{ + int ret = -ENOENT; + + mutex_lock(&root->log_mutex); + atomic_inc(&root->log_writers); + mutex_unlock(&root->log_mutex); + return ret; +} + +/* * indicate we're done making changes to the log tree * and wake up anyone waiting to do a sync */ -static int end_log_trans(struct btrfs_root *root) +int btrfs_end_log_trans(struct btrfs_root *root) { if (atomic_dec_and_test(&root->log_writers)) { smp_mb(); @@ -203,7 +266,6 @@ static int process_one_buffer(struct btrfs_root *log, mutex_lock(&log->fs_info->pinned_mutex); btrfs_update_pinned_extents(log->fs_info->extent_root, eb->start, eb->len, 1); - mutex_unlock(&log->fs_info->pinned_mutex); } if (btrfs_buffer_uptodate(eb, gen)) { @@ -603,6 +665,7 @@ static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans, ret = link_to_fixup_dir(trans, root, path, location.objectid); BUG_ON(ret); + ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len); BUG_ON(ret); kfree(name); @@ -804,6 +867,7 @@ conflict_again: victim_name_len)) { btrfs_inc_nlink(inode); btrfs_release_path(root, path); + ret = btrfs_unlink_inode(trans, root, dir, inode, victim_name, victim_name_len); @@ -922,13 +986,20 @@ static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans, key.offset--; btrfs_release_path(root, path); } - btrfs_free_path(path); + btrfs_release_path(root, path); if (nlink != inode->i_nlink) { inode->i_nlink = nlink; btrfs_update_inode(trans, root, inode); } BTRFS_I(inode)->index_cnt = (u64)-1; + if (inode->i_nlink == 0 && S_ISDIR(inode->i_mode)) { + ret = replay_dir_deletes(trans, root, NULL, path, + inode->i_ino, 1); + BUG_ON(ret); + } + btrfs_free_path(path); + return 0; } @@ -971,9 +1042,12 @@ static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans, iput(inode); - if (key.offset == 0) - break; - key.offset--; + /* + * fixup on a directory may create new entries, + * make sure we always look for the highset possible + * offset + */ + key.offset = (u64)-1; } btrfs_release_path(root, path); return 0; @@ -1313,11 +1387,11 @@ again: read_extent_buffer(eb, name, (unsigned long)(di + 1), name_len); log_di = NULL; - if (dir_key->type == BTRFS_DIR_ITEM_KEY) { + if (log && dir_key->type == BTRFS_DIR_ITEM_KEY) { log_di = btrfs_lookup_dir_item(trans, log, log_path, dir_key->objectid, name, name_len, 0); - } else if (dir_key->type == BTRFS_DIR_INDEX_KEY) { + } else if (log && dir_key->type == BTRFS_DIR_INDEX_KEY) { log_di = btrfs_lookup_dir_index_item(trans, log, log_path, dir_key->objectid, @@ -1378,7 +1452,7 @@ static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_root *log, struct btrfs_path *path, - u64 dirid) + u64 dirid, int del_all) { u64 range_start; u64 range_end; @@ -1408,10 +1482,14 @@ again: range_start = 0; range_end = 0; while (1) { - ret = find_dir_range(log, path, dirid, key_type, - &range_start, &range_end); - if (ret != 0) - break; + if (del_all) + range_end = (u64)-1; + else { + ret = find_dir_range(log, path, dirid, key_type, + &range_start, &range_end); + if (ret != 0) + break; + } dir_key.offset = range_start; while (1) { @@ -1437,7 +1515,8 @@ again: break; ret = check_item_in_log(trans, root, log, path, - log_path, dir, &found_key); + log_path, dir, + &found_key); BUG_ON(ret); if (found_key.offset == (u64)-1) break; @@ -1514,7 +1593,7 @@ static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb, mode = btrfs_inode_mode(eb, inode_item); if (S_ISDIR(mode)) { ret = replay_dir_deletes(wc->trans, - root, log, path, key.objectid); + root, log, path, key.objectid, 0); BUG_ON(ret); } ret = overwrite_item(wc->trans, root, path, @@ -1533,6 +1612,17 @@ static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb, root, inode, inode->i_size, BTRFS_EXTENT_DATA_KEY); BUG_ON(ret); + + /* if the nlink count is zero here, the iput + * will free the inode. We bump it to make + * sure it doesn't get freed until the link + * count fixup is done + */ + if (inode->i_nlink == 0) { + btrfs_inc_nlink(inode); + btrfs_update_inode(wc->trans, + root, inode); + } iput(inode); } ret = link_to_fixup_dir(wc->trans, root, @@ -1840,7 +1930,8 @@ static int update_log_root(struct btrfs_trans_handle *trans, return ret; } -static int wait_log_commit(struct btrfs_root *root, unsigned long transid) +static int wait_log_commit(struct btrfs_trans_handle *trans, + struct btrfs_root *root, unsigned long transid) { DEFINE_WAIT(wait); int index = transid % 2; @@ -1854,9 +1945,12 @@ static int wait_log_commit(struct btrfs_root *root, unsigned long transid) prepare_to_wait(&root->log_commit_wait[index], &wait, TASK_UNINTERRUPTIBLE); mutex_unlock(&root->log_mutex); - if (root->log_transid < transid + 2 && + + if (root->fs_info->last_trans_log_full_commit != + trans->transid && root->log_transid < transid + 2 && atomic_read(&root->log_commit[index])) schedule(); + finish_wait(&root->log_commit_wait[index], &wait); mutex_lock(&root->log_mutex); } while (root->log_transid < transid + 2 && @@ -1864,14 +1958,16 @@ static int wait_log_commit(struct btrfs_root *root, unsigned long transid) return 0; } -static int wait_for_writer(struct btrfs_root *root) +static int wait_for_writer(struct btrfs_trans_handle *trans, + struct btrfs_root *root) { DEFINE_WAIT(wait); while (atomic_read(&root->log_writers)) { prepare_to_wait(&root->log_writer_wait, &wait, TASK_UNINTERRUPTIBLE); mutex_unlock(&root->log_mutex); - if (atomic_read(&root->log_writers)) + if (root->fs_info->last_trans_log_full_commit != + trans->transid && atomic_read(&root->log_writers)) schedule(); mutex_lock(&root->log_mutex); finish_wait(&root->log_writer_wait, &wait); @@ -1882,7 +1978,14 @@ static int wait_for_writer(struct btrfs_root *root) /* * btrfs_sync_log does sends a given tree log down to the disk and * updates the super blocks to record it. When this call is done, - * you know that any inodes previously logged are safely on disk + * you know that any inodes previously logged are safely on disk only + * if it returns 0. + * + * Any other return value means you need to call btrfs_commit_transaction. + * Some of the edge cases for fsyncing directories that have had unlinks + * or renames done in the past mean that sometimes the only safe + * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN, + * that has happened. */ int btrfs_sync_log(struct btrfs_trans_handle *trans, struct btrfs_root *root) @@ -1896,7 +1999,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, mutex_lock(&root->log_mutex); index1 = root->log_transid % 2; if (atomic_read(&root->log_commit[index1])) { - wait_log_commit(root, root->log_transid); + wait_log_commit(trans, root, root->log_transid); mutex_unlock(&root->log_mutex); return 0; } @@ -1904,18 +2007,26 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, /* wait for previous tree log sync to complete */ if (atomic_read(&root->log_commit[(index1 + 1) % 2])) - wait_log_commit(root, root->log_transid - 1); + wait_log_commit(trans, root, root->log_transid - 1); while (1) { unsigned long batch = root->log_batch; mutex_unlock(&root->log_mutex); schedule_timeout_uninterruptible(1); mutex_lock(&root->log_mutex); - wait_for_writer(root); + + wait_for_writer(trans, root); if (batch == root->log_batch) break; } + /* bail out if we need to do a full commit */ + if (root->fs_info->last_trans_log_full_commit == trans->transid) { + ret = -EAGAIN; + mutex_unlock(&root->log_mutex); + goto out; + } + ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages); BUG_ON(ret); @@ -1951,16 +2062,29 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, index2 = log_root_tree->log_transid % 2; if (atomic_read(&log_root_tree->log_commit[index2])) { - wait_log_commit(log_root_tree, log_root_tree->log_transid); + wait_log_commit(trans, log_root_tree, + log_root_tree->log_transid); mutex_unlock(&log_root_tree->log_mutex); goto out; } atomic_set(&log_root_tree->log_commit[index2], 1); - if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) - wait_log_commit(log_root_tree, log_root_tree->log_transid - 1); + if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) { + wait_log_commit(trans, log_root_tree, + log_root_tree->log_transid - 1); + } + + wait_for_writer(trans, log_root_tree); - wait_for_writer(log_root_tree); + /* + * now that we've moved on to the tree of log tree roots, + * check the full commit flag again + */ + if (root->fs_info->last_trans_log_full_commit == trans->transid) { + mutex_unlock(&log_root_tree->log_mutex); + ret = -EAGAIN; + goto out_wake_log_root; + } ret = btrfs_write_and_wait_marked_extents(log_root_tree, &log_root_tree->dirty_log_pages); @@ -1985,7 +2109,9 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, * in and cause problems either. */ write_ctree_super(trans, root->fs_info->tree_root, 2); + ret = 0; +out_wake_log_root: atomic_set(&log_root_tree->log_commit[index2], 0); smp_mb(); if (waitqueue_active(&log_root_tree->log_commit_wait[index2])) @@ -1998,7 +2124,8 @@ out: return 0; } -/* * free all the extents used by the tree log. This should be called +/* + * free all the extents used by the tree log. This should be called * at commit time of the full transaction */ int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root) @@ -2132,7 +2259,7 @@ int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans, btrfs_free_path(path); mutex_unlock(&BTRFS_I(dir)->log_mutex); - end_log_trans(root); + btrfs_end_log_trans(root); return 0; } @@ -2159,7 +2286,7 @@ int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans, ret = btrfs_del_inode_ref(trans, log, name, name_len, inode->i_ino, dirid, &index); mutex_unlock(&BTRFS_I(inode)->log_mutex); - end_log_trans(root); + btrfs_end_log_trans(root); return ret; } @@ -2559,7 +2686,7 @@ static noinline int copy_items(struct btrfs_trans_handle *trans, * * This handles both files and directories. */ -static int __btrfs_log_inode(struct btrfs_trans_handle *trans, +static int btrfs_log_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, int inode_only) { @@ -2585,28 +2712,17 @@ static int __btrfs_log_inode(struct btrfs_trans_handle *trans, min_key.offset = 0; max_key.objectid = inode->i_ino; + + /* today the code can only do partial logging of directories */ + if (!S_ISDIR(inode->i_mode)) + inode_only = LOG_INODE_ALL; + if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode)) max_key.type = BTRFS_XATTR_ITEM_KEY; else max_key.type = (u8)-1; max_key.offset = (u64)-1; - /* - * if this inode has already been logged and we're in inode_only - * mode, we don't want to delete the things that have already - * been written to the log. - * - * But, if the inode has been through an inode_only log, - * the logged_trans field is not set. This allows us to catch - * any new names for this inode in the backrefs by logging it - * again - */ - if (inode_only == LOG_INODE_EXISTS && - BTRFS_I(inode)->logged_trans == trans->transid) { - btrfs_free_path(path); - btrfs_free_path(dst_path); - goto out; - } mutex_lock(&BTRFS_I(inode)->log_mutex); /* @@ -2693,7 +2809,6 @@ next_slot: if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) { btrfs_release_path(root, path); btrfs_release_path(log, dst_path); - BTRFS_I(inode)->log_dirty_trans = 0; ret = log_directory_changes(trans, root, inode, path, dst_path); BUG_ON(ret); } @@ -2702,19 +2817,69 @@ next_slot: btrfs_free_path(path); btrfs_free_path(dst_path); -out: return 0; } -int btrfs_log_inode(struct btrfs_trans_handle *trans, - struct btrfs_root *root, struct inode *inode, - int inode_only) +/* + * follow the dentry parent pointers up the chain and see if any + * of the directories in it require a full commit before they can + * be logged. Returns zero if nothing special needs to be done or 1 if + * a full commit is required. + */ +static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans, + struct inode *inode, + struct dentry *parent, + struct super_block *sb, + u64 last_committed) { - int ret; + int ret = 0; + struct btrfs_root *root; - start_log_trans(trans, root); - ret = __btrfs_log_inode(trans, root, inode, inode_only); - end_log_trans(root); + /* + * for regular files, if its inode is already on disk, we don't + * have to worry about the parents at all. This is because + * we can use the last_unlink_trans field to record renames + * and other fun in this file. + */ + if (S_ISREG(inode->i_mode) && + BTRFS_I(inode)->generation <= last_committed && + BTRFS_I(inode)->last_unlink_trans <= last_committed) + goto out; + + if (!S_ISDIR(inode->i_mode)) { + if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) + goto out; + inode = parent->d_inode; + } + + while (1) { + BTRFS_I(inode)->logged_trans = trans->transid; + smp_mb(); + + if (BTRFS_I(inode)->last_unlink_trans > last_committed) { + root = BTRFS_I(inode)->root; + + /* + * make sure any commits to the log are forced + * to be full commits + */ + root->fs_info->last_trans_log_full_commit = + trans->transid; + ret = 1; + break; + } + + if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) + break; + + if (parent == sb->s_root) + break; + + parent = parent->d_parent; + inode = parent->d_inode; + + } +out: return ret; } @@ -2724,31 +2889,65 @@ int btrfs_log_inode(struct btrfs_trans_handle *trans, * only logging is done of any parent directories that are older than * the last committed transaction */ -int btrfs_log_dentry(struct btrfs_trans_handle *trans, - struct btrfs_root *root, struct dentry *dentry) +int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct inode *inode, + struct dentry *parent, int exists_only) { - int inode_only = LOG_INODE_ALL; + int inode_only = exists_only ? LOG_INODE_EXISTS : LOG_INODE_ALL; struct super_block *sb; - int ret; + int ret = 0; + u64 last_committed = root->fs_info->last_trans_committed; + + sb = inode->i_sb; + + if (root->fs_info->last_trans_log_full_commit > + root->fs_info->last_trans_committed) { + ret = 1; + goto end_no_trans; + } + + ret = check_parent_dirs_for_sync(trans, inode, parent, + sb, last_committed); + if (ret) + goto end_no_trans; start_log_trans(trans, root); - sb = dentry->d_inode->i_sb; - while (1) { - ret = __btrfs_log_inode(trans, root, dentry->d_inode, - inode_only); - BUG_ON(ret); - inode_only = LOG_INODE_EXISTS; - dentry = dentry->d_parent; - if (!dentry || !dentry->d_inode || sb != dentry->d_inode->i_sb) + ret = btrfs_log_inode(trans, root, inode, inode_only); + BUG_ON(ret); + + /* + * for regular files, if its inode is already on disk, we don't + * have to worry about the parents at all. This is because + * we can use the last_unlink_trans field to record renames + * and other fun in this file. + */ + if (S_ISREG(inode->i_mode) && + BTRFS_I(inode)->generation <= last_committed && + BTRFS_I(inode)->last_unlink_trans <= last_committed) + goto no_parent; + + inode_only = LOG_INODE_EXISTS; + while (1) { + if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) break; - if (BTRFS_I(dentry->d_inode)->generation <= - root->fs_info->last_trans_committed) + inode = parent->d_inode; + if (BTRFS_I(inode)->generation > + root->fs_info->last_trans_committed) { + ret = btrfs_log_inode(trans, root, inode, inode_only); + BUG_ON(ret); + } + if (parent == sb->s_root) break; + + parent = parent->d_parent; } - end_log_trans(root); - return 0; +no_parent: + ret = 0; + btrfs_end_log_trans(root); +end_no_trans: + return ret; } /* @@ -2760,12 +2959,8 @@ int btrfs_log_dentry(struct btrfs_trans_handle *trans, int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct dentry *dentry) { - u64 gen; - gen = root->fs_info->last_trans_new_blockgroup; - if (gen > root->fs_info->last_trans_committed) - return 1; - else - return btrfs_log_dentry(trans, root, dentry); + return btrfs_log_inode_parent(trans, root, dentry->d_inode, + dentry->d_parent, 0); } /* @@ -2884,3 +3079,94 @@ again: kfree(log_root_tree); return 0; } + +/* + * there are some corner cases where we want to force a full + * commit instead of allowing a directory to be logged. + * + * They revolve around files there were unlinked from the directory, and + * this function updates the parent directory so that a full commit is + * properly done if it is fsync'd later after the unlinks are done. + */ +void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans, + struct inode *dir, struct inode *inode, + int for_rename) +{ + /* + * when we're logging a file, if it hasn't been renamed + * or unlinked, and its inode is fully committed on disk, + * we don't have to worry about walking up the directory chain + * to log its parents. + * + * So, we use the last_unlink_trans field to put this transid + * into the file. When the file is logged we check it and + * don't log the parents if the file is fully on disk. + */ + if (S_ISREG(inode->i_mode)) + BTRFS_I(inode)->last_unlink_trans = trans->transid; + + /* + * if this directory was already logged any new + * names for this file/dir will get recorded + */ + smp_mb(); + if (BTRFS_I(dir)->logged_trans == trans->transid) + return; + + /* + * if the inode we're about to unlink was logged, + * the log will be properly updated for any new names + */ + if (BTRFS_I(inode)->logged_trans == trans->transid) + return; + + /* + * when renaming files across directories, if the directory + * there we're unlinking from gets fsync'd later on, there's + * no way to find the destination directory later and fsync it + * properly. So, we have to be conservative and force commits + * so the new name gets discovered. + */ + if (for_rename) + goto record; + + /* we can safely do the unlink without any special recording */ + return; + +record: + BTRFS_I(dir)->last_unlink_trans = trans->transid; +} + +/* + * Call this after adding a new name for a file and it will properly + * update the log to reflect the new name. + * + * It will return zero if all goes well, and it will return 1 if a + * full transaction commit is required. + */ +int btrfs_log_new_name(struct btrfs_trans_handle *trans, + struct inode *inode, struct inode *old_dir, + struct dentry *parent) +{ + struct btrfs_root * root = BTRFS_I(inode)->root; + + /* + * this will force the logging code to walk the dentry chain + * up for the file + */ + if (S_ISREG(inode->i_mode)) + BTRFS_I(inode)->last_unlink_trans = trans->transid; + + /* + * if this inode hasn't been logged and directory we're renaming it + * from hasn't been logged, we don't need to log it + */ + if (BTRFS_I(inode)->logged_trans <= + root->fs_info->last_trans_committed && + (!old_dir || BTRFS_I(old_dir)->logged_trans <= + root->fs_info->last_trans_committed)) + return 0; + + return btrfs_log_inode_parent(trans, root, inode, parent, 1); +} + |