2008-09-22 10:58:00

by Takashi Sato

[permalink] [raw]
Subject: [PATCH 3/10] ext4: Fix error handling in write_super_lockfs/unlockfs

I've changed write_super_lockfs/unlockfs so that they return an error
in case of an I/O failure.

Signed-off-by: Takashi Sato <[email protected]>
Signed-off-by: Masayuki Hamaguchi <[email protected]>
---
super.c | 39 +++++++++++++++++++++++++++------------
1 file changed, 27 insertions(+), 12 deletions(-)

diff -uprN -X linux-2.6.27-rc7-lockfs-ext3/Documentation/dontdiff linux-2.6.27-rc7-lockfs-ext3/fs/ext4/super.c linux-2.6
.27-rc7-lockfs-ext4/fs/ext4/super.c
--- linux-2.6.27-rc7-lockfs-ext3/fs/ext4/super.c 2008-09-22 07:29:55.000000000 +0900
+++ linux-2.6.27-rc7-lockfs-ext4/fs/ext4/super.c 2008-09-22 10:46:36.000000000 +0900
@@ -49,7 +49,7 @@ static int ext4_load_journal(struct supe
unsigned long journal_devnum);
static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
unsigned int);
-static void ext4_commit_super(struct super_block *sb,
+static int ext4_commit_super(struct super_block *sb,
struct ext4_super_block *es, int sync);
static void ext4_mark_recovery_complete(struct super_block *sb,
struct ext4_super_block *es);
@@ -60,9 +60,9 @@ static const char *ext4_decode_error(str
char nbuf[16]);
static int ext4_remount(struct super_block *sb, int *flags, char *data);
static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
-static void ext4_unlockfs(struct super_block *sb);
+static int ext4_unlockfs(struct super_block *sb);
static void ext4_write_super(struct super_block *sb);
-static void ext4_write_super_lockfs(struct super_block *sb);
+static int ext4_write_super_lockfs(struct super_block *sb);


ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
@@ -2792,20 +2792,22 @@ static int ext4_create_journal(struct su
return 0;
}

-static void ext4_commit_super(struct super_block *sb,
+static int ext4_commit_super(struct super_block *sb,
struct ext4_super_block *es, int sync)
{
struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
+ int error = 0;

if (!sbh)
- return;
+ return error;
es->s_wtime = cpu_to_le32(get_seconds());
ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
BUFFER_TRACE(sbh, "marking dirty");
mark_buffer_dirty(sbh);
if (sync)
- sync_dirty_buffer(sbh);
+ error = sync_dirty_buffer(sbh);
+ return error;
}


@@ -2919,37 +2921,50 @@ static int ext4_sync_fs(struct super_blo
* LVM calls this function before a (read-only) snapshot is created. This
* gives us a chance to flush the journal completely and mark the fs clean.
*/
-static void ext4_write_super_lockfs(struct super_block *sb)
+static int ext4_write_super_lockfs(struct super_block *sb)
{
+ int error = 0;
+ journal_t *journal;
sb->s_dirt = 0;

if (!(sb->s_flags & MS_RDONLY)) {
- journal_t *journal = EXT4_SB(sb)->s_journal;
+ journal = EXT4_SB(sb)->s_journal;

/* Now we set up the journal barrier. */
jbd2_journal_lock_updates(journal);
- jbd2_journal_flush(journal);
+ error = jbd2_journal_flush(journal);
+ if (error)
+ goto out;

/* Journal blocked and flushed, clear needs_recovery flag. */
EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
- ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+ error = ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+ if (error)
+ goto out;
}
+ return 0;
+
+out:
+ jbd2_journal_unlock_updates(journal);
+ return error;
}

/*
* Called by LVM after the snapshot is done. We need to reset the RECOVER
* flag here, even though the filesystem is not technically dirty yet.
*/
-static void ext4_unlockfs(struct super_block *sb)
+static int ext4_unlockfs(struct super_block *sb)
{
+ int error = 0;
if (!(sb->s_flags & MS_RDONLY)) {
lock_super(sb);
/* Reser the needs_recovery flag before the fs is unlocked. */
EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
- ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+ error = ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
unlock_super(sb);
jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
}
+ return error;
}

static int ext4_remount(struct super_block *sb, int *flags, char *data)