quota: Split ->set_xstate callback into two

Split ->set_xstate callback into two callbacks - one for turning quotas
on (->quota_enable) and one for turning quotas off (->quota_disable). That
way we don't have to pass quotactl command into the callback which seems
cleaner.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/xfs/xfs_quotaops.c b/fs/xfs/xfs_quotaops.c
index a226203..6923905 100644
--- a/fs/xfs/xfs_quotaops.c
+++ b/fs/xfs/xfs_quotaops.c
@@ -64,19 +64,10 @@
 	return xfs_qm_scall_getqstatv(mp, fqs);
 }
 
-STATIC int
-xfs_fs_set_xstate(
-	struct super_block	*sb,
-	unsigned int		uflags,
-	int			op)
+static unsigned int
+xfs_quota_flags(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_RUNNING(mp))
-		return -ENOSYS;
+	unsigned int flags = 0;
 
 	if (uflags & FS_QUOTA_UDQ_ACCT)
 		flags |= XFS_UQUOTA_ACCT;
@@ -91,16 +82,39 @@
 	if (uflags & FS_QUOTA_PDQ_ENFD)
 		flags |= XFS_PQUOTA_ENFD;
 
-	switch (op) {
-	case Q_XQUOTAON:
-		return xfs_qm_scall_quotaon(mp, flags);
-	case Q_XQUOTAOFF:
-		if (!XFS_IS_QUOTA_ON(mp))
-			return -EINVAL;
-		return xfs_qm_scall_quotaoff(mp, flags);
-	}
+	return flags;
+}
 
-	return -EINVAL;
+STATIC int
+xfs_quota_enable(
+	struct super_block	*sb,
+	unsigned int		uflags)
+{
+	struct xfs_mount	*mp = XFS_M(sb);
+
+	if (sb->s_flags & MS_RDONLY)
+		return -EROFS;
+	if (!XFS_IS_QUOTA_RUNNING(mp))
+		return -ENOSYS;
+
+	return xfs_qm_scall_quotaon(mp, xfs_quota_flags(uflags));
+}
+
+STATIC int
+xfs_quota_disable(
+	struct super_block	*sb,
+	unsigned int		uflags)
+{
+	struct xfs_mount	*mp = XFS_M(sb);
+
+	if (sb->s_flags & MS_RDONLY)
+		return -EROFS;
+	if (!XFS_IS_QUOTA_RUNNING(mp))
+		return -ENOSYS;
+	if (!XFS_IS_QUOTA_ON(mp))
+		return -EINVAL;
+
+	return xfs_qm_scall_quotaoff(mp, xfs_quota_flags(uflags));
 }
 
 STATIC int
@@ -166,7 +180,8 @@
 const struct quotactl_ops xfs_quotactl_operations = {
 	.get_xstatev		= xfs_fs_get_xstatev,
 	.get_xstate		= xfs_fs_get_xstate,
-	.set_xstate		= xfs_fs_set_xstate,
+	.quota_enable		= xfs_quota_enable,
+	.quota_disable		= xfs_quota_disable,
 	.rm_xquota		= xfs_fs_rm_xquota,
 	.get_dqblk		= xfs_fs_get_dqblk,
 	.set_dqblk		= xfs_fs_set_dqblk,