[PATCH 3.16 075/346] ext4: short-cut orphan cleanup on error

[Ben Hutchings]

3.16.39-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Vegard Nossum <vegard.nossum@xxxxxxxxxx>

commit c65d5c6c81a1f27dec5f627f67840726fcd146de upstream.

If we encounter a filesystem error during orphan cleanup, we should stop.
Otherwise, we may end up in an infinite loop where the same inode is
processed again and again.

    EXT4-fs (loop0): warning: checktime reached, running e2fsck is recommended
    EXT4-fs error (device loop0): ext4_mb_generate_buddy:758: group 2, block bitmap and bg descriptor inconsistent: 6117 vs 0 free clusters
    Aborting journal on device loop0-8.
    EXT4-fs (loop0): Remounting filesystem read-only
    EXT4-fs error (device loop0) in ext4_free_blocks:4895: Journal has aborted
    EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
    EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
    EXT4-fs error (device loop0) in ext4_ext_remove_space:3068: IO failure
    EXT4-fs error (device loop0) in ext4_ext_truncate:4667: Journal has aborted
    EXT4-fs error (device loop0) in ext4_orphan_del:2927: Journal has aborted
    EXT4-fs error (device loop0) in ext4_do_update_inode:4893: Journal has aborted
    EXT4-fs (loop0): Inode 16 (00000000618192a0): orphan list check failed!
    [...]
    EXT4-fs (loop0): Inode 16 (0000000061819748): orphan list check failed!
    [...]
    EXT4-fs (loop0): Inode 16 (0000000061819bf0): orphan list check failed!
    [...]

See-also: c9eb13a9105 ("ext4: fix hang when processing corrupted orphaned inode list")
Cc: Jan Kara <jack@xxxxxxx>
Signed-off-by: Vegard Nossum <vegard.nossum@xxxxxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 fs/ext4/super.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2228,6 +2228,16 @@ static void ext4_orphan_cleanup(struct s
 	while (es->s_last_orphan) {
 		struct inode *inode;
 
+		/*
+		 * We may have encountered an error during cleanup; if
+		 * so, skip the rest.
+		 */
+		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
+			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
+			es->s_last_orphan = 0;
+			break;
+		}
+
 		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
 		if (IS_ERR(inode)) {
 			es->s_last_orphan = 0;