diff options
author | Liu Bo <bo.li.liu@oracle.com> | 2013-10-29 10:45:05 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-20 07:49:09 -0800 |
commit | 9e5787dec9c785cc58e27c03d9c3e5536d18698a (patch) | |
tree | 675ce6d9daa747b3efebdb25446d7b6219c593f9 | |
parent | 486d1e163be2d32150a053c7ac3fc853ba6fd998 (diff) | |
download | lwn-9e5787dec9c785cc58e27c03d9c3e5536d18698a.tar.gz lwn-9e5787dec9c785cc58e27c03d9c3e5536d18698a.zip |
Btrfs: do not run snapshot-aware defragment on error
commit 6f519564d7d978c00351d9ab6abac3deeac31621 upstream.
If something wrong happens in write endio, running snapshot-aware defragment
can end up with undefined results, maybe a crash, so we should avoid it.
In order to share similar code, this also adds a helper to free the struct for
snapshot-aware defrag.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | fs/btrfs/inode.c | 47 |
1 files changed, 28 insertions, 19 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 51e3afa78354..8b8eff051493 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2367,10 +2367,23 @@ out_unlock: return ret; } +static void free_sa_defrag_extent(struct new_sa_defrag_extent *new) +{ + struct old_sa_defrag_extent *old, *tmp; + + if (!new) + return; + + list_for_each_entry_safe(old, tmp, &new->head, list) { + list_del(&old->list); + kfree(old); + } + kfree(new); +} + static void relink_file_extents(struct new_sa_defrag_extent *new) { struct btrfs_path *path; - struct old_sa_defrag_extent *old, *tmp; struct sa_defrag_extent_backref *backref; struct sa_defrag_extent_backref *prev = NULL; struct inode *inode; @@ -2413,16 +2426,11 @@ static void relink_file_extents(struct new_sa_defrag_extent *new) kfree(prev); btrfs_free_path(path); - - list_for_each_entry_safe(old, tmp, &new->head, list) { - list_del(&old->list); - kfree(old); - } out: + free_sa_defrag_extent(new); + atomic_dec(&root->fs_info->defrag_running); wake_up(&root->fs_info->transaction_wait); - - kfree(new); } static struct new_sa_defrag_extent * @@ -2432,7 +2440,7 @@ record_old_file_extents(struct inode *inode, struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_path *path; struct btrfs_key key; - struct old_sa_defrag_extent *old, *tmp; + struct old_sa_defrag_extent *old; struct new_sa_defrag_extent *new; int ret; @@ -2480,7 +2488,7 @@ record_old_file_extents(struct inode *inode, if (slot >= btrfs_header_nritems(l)) { ret = btrfs_next_leaf(root, path); if (ret < 0) - goto out_free_list; + goto out_free_path; else if (ret > 0) break; continue; @@ -2509,7 +2517,7 @@ record_old_file_extents(struct inode *inode, old = kmalloc(sizeof(*old), GFP_NOFS); if (!old) - goto out_free_list; + goto out_free_path; offset = max(new->file_pos, key.offset); end = min(new->file_pos + new->len, key.offset + num_bytes); @@ -2531,15 +2539,10 @@ next: return new; -out_free_list: - list_for_each_entry_safe(old, tmp, &new->head, list) { - list_del(&old->list); - kfree(old); - } out_free_path: btrfs_free_path(path); out_kfree: - kfree(new); + free_sa_defrag_extent(new); return NULL; } @@ -2710,8 +2713,14 @@ out: btrfs_remove_ordered_extent(inode, ordered_extent); /* for snapshot-aware defrag */ - if (new) - relink_file_extents(new); + if (new) { + if (ret) { + free_sa_defrag_extent(new); + atomic_dec(&root->fs_info->defrag_running); + } else { + relink_file_extents(new); + } + } /* once for us */ btrfs_put_ordered_extent(ordered_extent); |