xfs: use xfs_ilock_data_map_shared in xfs_qm_dqtobp

We might not have read in the extent list at this point, so make sure we
take the ilock exclusively if we have to do so.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
index 6b1e695caf0ebf8bf256150d2efc9483667b837d..7aeb4c895b3294e84731b44f6f75487d6a655c3e 100644 (file)
--- a/fs/xfs/xfs_dquot.c
+++ b/fs/xfs/xfs_dquot.c
@@ -469,16 +469,17 @@ 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;
 
        dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
 
-       xfs_ilock(quotip, XFS_ILOCK_SHARED);
+       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.
                 */
-               xfs_iunlock(quotip, XFS_ILOCK_SHARED);
+               xfs_iunlock(quotip, lock_mode);
                return ESRCH;
        }
 
@@ -488,7 +489,7 @@ xfs_qm_dqtobp(
        error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
                               XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
 
-       xfs_iunlock(quotip, XFS_ILOCK_SHARED);
+       xfs_iunlock(quotip, lock_mode);
        if (error)
                return error;