quota: Silence lockdep on quota_on

Commit d01730d74d2b0155da50d44555001706294014f7 didn't completely fix
the problem since we still take dqio_mutex and i_mutex in the wrong
order. Move taking of i_mutex further down (luckily it's needed only
for updating inode flags) below where dqio_mutex is taken.

Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 4 insertions, 3 deletions

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 70f36c043d62..38f7bd559f35 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -2043,7 +2043,6 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
                 invalidate_bdev(sb->s_bdev);
         }
         mutex_lock(&dqopt->dqonoff_mutex);
-        mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
         if (sb_has_quota_loaded(sb, type)) {
                 error = -EBUSY;
                 goto out_lock;
@@ -2054,9 +2053,11 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
                  * possible) Also nobody should write to the file - we use
                  * special IO operations which ignore the immutable bit. */
                 down_write(&dqopt->dqptr_sem);
+                mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
                 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE |
                                              S_NOQUOTA);
                 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
+                mutex_unlock(&inode->i_mutex);
                 up_write(&dqopt->dqptr_sem);
                 sb->dq_op->drop(inode);
         }
@@ -2080,7 +2081,6 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
                 goto out_file_init;
         }
         mutex_unlock(&dqopt->dqio_mutex);
-        mutex_unlock(&inode->i_mutex);
         spin_lock(&dq_state_lock);
         dqopt->flags |= dquot_state_flag(flags, type);
         spin_unlock(&dq_state_lock);
@@ -2096,13 +2096,14 @@ out_file_init:
 out_lock:
         if (oldflags != -1) {
                 down_write(&dqopt->dqptr_sem);
+                mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
                 /* Set the flags back (in the case of accidental quotaon()
                  * on a wrong file we don't want to mess up the flags) */
                 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
                 inode->i_flags |= oldflags;
+                mutex_unlock(&inode->i_mutex);
                 up_write(&dqopt->dqptr_sem);
         }
-        mutex_unlock(&inode->i_mutex);
         mutex_unlock(&dqopt->dqonoff_mutex);
 out_fmt:
         put_quota_format(fmt);