3.2-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jan Kara <j...@suse.cz>
commit 3bb3e1fc47aca554e7e2cc4deeddc24750987ac2 upstream.
When remounting reiserfs dquot_suspend() or dquot_resume() can be called.
These functions take dqonoff_mutex which ranks above write lock so we have
to drop it before calling into quota code.
Signed-off-by: Jan Kara <j...@suse.cz>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
fs/reiserfs/super.c | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 deletions(-)
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -1207,7 +1207,7 @@ static int reiserfs_remount(struct super
kfree(qf_names[i]);
#endif
err = -EINVAL;
- goto out_err;
+ goto out_unlock;
}
#ifdef CONFIG_QUOTA
handle_quota_files(s, qf_names, &qfmt);
@@ -1250,7 +1250,7 @@ static int reiserfs_remount(struct super
if (blocks) {
err = reiserfs_resize(s, blocks);
if (err != 0)
- goto out_err;
+ goto out_unlock;
}
if (*mount_flags & MS_RDONLY) {
@@ -1260,9 +1260,15 @@ static int reiserfs_remount(struct super
/* it is read-only already */
goto out_ok;
+ /*
+ * Drop write lock. Quota will retake it when needed and lock
+ * ordering requires calling dquot_suspend() without it.
+ */
+ reiserfs_write_unlock(s);
err = dquot_suspend(s, -1);
if (err < 0)
goto out_err;
+ reiserfs_write_lock(s);
/* try to remount file system with read-only permissions */
if (sb_umount_state(rs) == REISERFS_VALID_FS
@@ -1272,7 +1278,7 @@ static int reiserfs_remount(struct super
err = journal_begin(&th, s, 10);
if (err)
- goto out_err;
+ goto out_unlock;
/* Mounting a rw partition read-only. */
reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
@@ -1287,7 +1293,7 @@ static int reiserfs_remount(struct super
if (reiserfs_is_journal_aborted(journal)) {
err = journal->j_errno;
- goto out_err;
+ goto out_unlock;
}
handle_data_mode(s, mount_options);
@@ -1296,7 +1302,7 @@ static int reiserfs_remount(struct super
s->s_flags &= ~MS_RDONLY; /* now it is safe to call
journal_begin */
err = journal_begin(&th, s, 10);
if (err)
- goto out_err;
+ goto out_unlock;
/* Mount a partition which is read-only, read-write */
reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
@@ -1313,11 +1319,17 @@ static int reiserfs_remount(struct super
SB_JOURNAL(s)->j_must_wait = 1;
err = journal_end(&th, s, 10);
if (err)
- goto out_err;
+ goto out_unlock;
s->s_dirt = 0;
if (!(*mount_flags & MS_RDONLY)) {
+ /*
+ * Drop write lock. Quota will retake it when needed and lock
+ * ordering requires calling dquot_resume() without it.
+ */
+ reiserfs_write_unlock(s);
dquot_resume(s, -1);
+ reiserfs_write_lock(s);
finish_unfinished(s);
reiserfs_xattr_init(s, *mount_flags);
}
@@ -1327,9 +1339,10 @@ out_ok:
reiserfs_write_unlock(s);
return 0;
+out_unlock:
+ reiserfs_write_unlock(s);
out_err:
kfree(new_opts);
- reiserfs_write_unlock(s);
return err;
}
--
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