xfs: fix Q_XQUOTARM ioctl

The Q_XQUOTARM quotactl was not working properly, because
we weren't passing around proper flags.  The xfs_fs_set_xstate()
ioctl handler used the same flags for Q_XQUOTAON/OFF as
well as for Q_XQUOTARM, but Q_XQUOTAON/OFF look for
XFS_UQUOTA_ACCT, XFS_UQUOTA_ENFD, XFS_GQUOTA_ACCT etc,
i.e. quota type + state, while Q_XQUOTARM looks only for
the type of quota, i.e. XFS_DQ_USER, XFS_DQ_GROUP etc.

Unfortunately these flag spaces overlap a bit, so we
got semi-random results for Q_XQUOTARM; i.e. the value
for XFS_DQ_USER == XFS_UQUOTA_ACCT, etc.  yeargh.

Add a new quotactl op vector specifically for the QUOTARM
operation, since it operates with a different flag space.

This has been broken more or less forever, AFAICT.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>


diff --git a/fs/xfs/xfs_quotaops.c b/fs/xfs/xfs_quotaops.c
index af33caf..2ad1b98 100644
--- a/fs/xfs/xfs_quotaops.c
+++ b/fs/xfs/xfs_quotaops.c
@@ -100,16 +100,36 @@
 		if (!XFS_IS_QUOTA_ON(mp))
 			return -EINVAL;
 		return -xfs_qm_scall_quotaoff(mp, flags);
-	case Q_XQUOTARM:
-		if (XFS_IS_QUOTA_ON(mp))
-			return -EINVAL;
-		return -xfs_qm_scall_trunc_qfiles(mp, flags);
 	}
 
 	return -EINVAL;
 }
 
 STATIC int
+xfs_fs_rm_xquota(
+	struct super_block	*sb,
+	unsigned int		uflags)
+{
+	struct xfs_mount	*mp = XFS_M(sb);
+	unsigned int		flags = 0;
+	
+	if (sb->s_flags & MS_RDONLY)
+		return -EROFS;
+
+	if (XFS_IS_QUOTA_ON(mp))
+		return -EINVAL;
+
+	if (uflags & FS_USER_QUOTA)
+		flags |= XFS_DQ_USER;
+	if (uflags & FS_GROUP_QUOTA)
+		flags |= XFS_DQ_GROUP;
+	if (uflags & FS_USER_QUOTA)
+		flags |= XFS_DQ_PROJ;
+
+	return -xfs_qm_scall_trunc_qfiles(mp, flags);
+}	
+
+STATIC int
 xfs_fs_get_dqblk(
 	struct super_block	*sb,
 	struct kqid		qid,
@@ -149,6 +169,7 @@
 	.get_xstatev		= xfs_fs_get_xstatev,
 	.get_xstate		= xfs_fs_get_xstate,
 	.set_xstate		= xfs_fs_set_xstate,
+	.rm_xquota		= xfs_fs_rm_xquota,
 	.get_dqblk		= xfs_fs_get_dqblk,
 	.set_dqblk		= xfs_fs_set_dqblk,
 };