Revert "xfs: grab dquots without taking the ilock"

This reverts commit 50e0bdbe.

The new XFS_QMOPT_NOLOCK isn't used at all, and conditional locking based
on a flag is always the wrong thing to do - we should be having helpers
that can be called without the lock instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/libxfs/xfs_quota_defs.h

@@ -136,8 +136,6 @@ typedef uint16_t	xfs_qwarncnt_t;
  */
 #define XFS_QMOPT_INHERIT	0x1000000
 
-#define XFS_QMOPT_NOLOCK	0x2000000 /* don't ilock during dqget */
-
 /*
  * flags to xfs_trans_mod_dquot.
  */

fs/xfs/xfs_dquot.c

@@ -472,22 +472,17 @@ xfs_qm_dqtobp(
 	struct xfs_mount	*mp = dqp->q_mount;
 	xfs_dqid_t		id = be32_to_cpu(dqp->q_core.d_id);
 	struct xfs_trans	*tp = (tpp ? *tpp : NULL);
-	uint			lock_mode = 0;
+	uint			lock_mode;
 
 	quotip = xfs_quota_inode(dqp->q_mount, dqp->dq_flags);
 	dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
 
-	ASSERT(!(flags & XFS_QMOPT_NOLOCK) ||
-		xfs_isilocked(quotip, XFS_ILOCK_SHARED) ||
-		xfs_isilocked(quotip, XFS_ILOCK_EXCL));
-	if (!(flags & XFS_QMOPT_NOLOCK))
 	lock_mode = xfs_ilock_data_map_shared(quotip);
 	if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
 		/*
 		 * Return if this type of quotas is turned off while we
 		 * didn't have the quota inode lock.
 		 */
-		if (lock_mode)
 		xfs_iunlock(quotip, lock_mode);
 		return -ESRCH;
 	}
@@ -498,7 +493,6 @@ xfs_qm_dqtobp(
 	error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
 			       XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
 
-	if (lock_mode)
 	xfs_iunlock(quotip, lock_mode);
 	if (error)
 		return error;