xfs: Define a new function xfs_is_quota_inode()

In preparation for combined pquota/gquota support, define
a new function to check if the given inode is a quota inode.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

fs/xfs/xfs_itable.c

@@ -43,7 +43,7 @@ xfs_internal_inum(
 {
 	return (ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
 		(xfs_sb_version_hasquota(&mp->m_sb) &&
-		 (ino == mp->m_sb.sb_uquotino || ino == mp->m_sb.sb_gquotino)));
+		 xfs_is_quota_inode(&mp->m_sb, ino)));
 }
 
 /*

fs/xfs/xfs_qm.c

@@ -489,8 +489,7 @@ xfs_qm_need_dqattach(
 		return false;
 	if (!XFS_NOT_DQATTACHED(mp, ip))
 		return false;
-	if (ip->i_ino == mp->m_sb.sb_uquotino ||
-	    ip->i_ino == mp->m_sb.sb_gquotino)
+	if (xfs_is_quota_inode(&mp->m_sb, ip->i_ino))
 		return false;
 	return true;
 }
@@ -606,8 +605,7 @@ xfs_qm_dqdetach(
 
 	trace_xfs_dquot_dqdetach(ip);
 
-	ASSERT(ip->i_ino != ip->i_mount->m_sb.sb_uquotino);
-	ASSERT(ip->i_ino != ip->i_mount->m_sb.sb_gquotino);
+	ASSERT(!xfs_is_quota_inode(&ip->i_mount->m_sb, ip->i_ino));
 	if (ip->i_udquot) {
 		xfs_qm_dqrele(ip->i_udquot);
 		ip->i_udquot = NULL;
@@ -1152,7 +1150,7 @@ xfs_qm_dqusage_adjust(
 	 * rootino must have its resources accounted for, not so with the quota
 	 * inodes.
 	 */
-	if (ino == mp->m_sb.sb_uquotino || ino == mp->m_sb.sb_gquotino) {
+	if (xfs_is_quota_inode(&mp->m_sb, ino)) {
 		*res = BULKSTAT_RV_NOTHING;
 		return XFS_ERROR(EINVAL);
 	}

fs/xfs/xfs_sb.h

@@ -618,6 +618,12 @@ xfs_sb_has_incompat_log_feature(
 	return (sbp->sb_features_log_incompat & feature) != 0;
 }
 
+static inline bool
+xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
+{
+	return (ino == sbp->sb_uquotino || ino == sbp->sb_gquotino);
+}
+
 /*
  * end of superblock version macros
  */

fs/xfs/xfs_trans_dquot.c

@@ -157,8 +157,7 @@ xfs_trans_mod_dquot_byino(
 
 	if (!XFS_IS_QUOTA_RUNNING(mp) ||
 	    !XFS_IS_QUOTA_ON(mp) ||
-	    ip->i_ino == mp->m_sb.sb_uquotino ||
-	    ip->i_ino == mp->m_sb.sb_gquotino)
+	    xfs_is_quota_inode(&mp->m_sb, ip->i_ino))
 		return;
 
 	if (tp->t_dqinfo == NULL)
@@ -816,8 +815,7 @@ xfs_trans_reserve_quota_nblks(
 	if (XFS_IS_PQUOTA_ON(mp))
 		flags |= XFS_QMOPT_ENOSPC;
 
-	ASSERT(ip->i_ino != mp->m_sb.sb_uquotino);
-	ASSERT(ip->i_ino != mp->m_sb.sb_gquotino);
+	ASSERT(!xfs_is_quota_inode(&mp->m_sb, ip->i_ino));
 
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 	ASSERT((flags & ~(XFS_QMOPT_FORCE_RES | XFS_QMOPT_ENOSPC)) ==