xfs: Extend project quotas to support 32bit project ids

This patch adds support for 32bit project quota identifiers.

On disk format is backward compatible with 16bit projid numbers. projid
on disk is now kept in two 16bit values - di_projid_lo (which holds the
same position as old 16bit projid value) and new di_projid_hi (takes
existing padding) and converts from/to 32bit value on the fly.

xfs_admin (for existing fs), mkfs.xfs (for new fs) needs to be used
to enable PROJID32BIT support.

Signed-off-by: Arkadiusz Miƛkiewicz <arekm@maven.pl>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
index 10206be..2ea238f6 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl.c
@@ -790,7 +790,7 @@
 	xfs_ilock(ip, XFS_ILOCK_SHARED);
 	fa.fsx_xflags = xfs_ip2xflags(ip);
 	fa.fsx_extsize = ip->i_d.di_extsize << ip->i_mount->m_sb.sb_blocklog;
-	fa.fsx_projid = ip->i_d.di_projid;
+	fa.fsx_projid = xfs_get_projid(ip);
 
 	if (attr) {
 		if (ip->i_afp) {
@@ -909,10 +909,10 @@
 		return XFS_ERROR(EIO);
 
 	/*
-	 * Disallow 32bit project ids because on-disk structure
-	 * is 16bit only.
+	 * Disallow 32bit project ids when projid32bit feature is not enabled.
 	 */
-	if ((mask & FSX_PROJID) && (fa->fsx_projid > (__uint16_t)-1))
+	if ((mask & FSX_PROJID) && (fa->fsx_projid > (__uint16_t)-1) &&
+			!xfs_sb_version_hasprojid32bit(&ip->i_mount->m_sb))
 		return XFS_ERROR(EINVAL);
 
 	/*
@@ -961,7 +961,7 @@
 	if (mask & FSX_PROJID) {
 		if (XFS_IS_QUOTA_RUNNING(mp) &&
 		    XFS_IS_PQUOTA_ON(mp) &&
-		    ip->i_d.di_projid != fa->fsx_projid) {
+		    xfs_get_projid(ip) != fa->fsx_projid) {
 			ASSERT(tp);
 			code = xfs_qm_vop_chown_reserve(tp, ip, udqp, gdqp,
 						capable(CAP_FOWNER) ?
@@ -1063,12 +1063,12 @@
 		 * Change the ownerships and register quota modifications
 		 * in the transaction.
 		 */
-		if (ip->i_d.di_projid != fa->fsx_projid) {
+		if (xfs_get_projid(ip) != fa->fsx_projid) {
 			if (XFS_IS_QUOTA_RUNNING(mp) && XFS_IS_PQUOTA_ON(mp)) {
 				olddquot = xfs_qm_vop_chown(tp, ip,
 							&ip->i_gdquot, gdqp);
 			}
-			ip->i_d.di_projid = fa->fsx_projid;
+			xfs_set_projid(ip, fa->fsx_projid);
 
 			/*
 			 * We may have to rev the inode as well as
diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.c b/fs/xfs/linux-2.6/xfs_ioctl32.c
index 464bcc7..b3486df 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl32.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl32.c
@@ -164,7 +164,8 @@
 	    get_user(bstat->bs_extsize,	&bstat32->bs_extsize)	||
 	    get_user(bstat->bs_extents,	&bstat32->bs_extents)	||
 	    get_user(bstat->bs_gen,	&bstat32->bs_gen)	||
-	    get_user(bstat->bs_projid,	&bstat32->bs_projid)	||
+	    get_user(bstat->bs_projid_lo, &bstat32->bs_projid_lo) ||
+	    get_user(bstat->bs_projid_hi, &bstat32->bs_projid_hi) ||
 	    get_user(bstat->bs_dmevmask, &bstat32->bs_dmevmask)	||
 	    get_user(bstat->bs_dmstate,	&bstat32->bs_dmstate)	||
 	    get_user(bstat->bs_aextents, &bstat32->bs_aextents))
@@ -218,6 +219,7 @@
 	    put_user(buffer->bs_extents,  &p32->bs_extents)	||
 	    put_user(buffer->bs_gen,	  &p32->bs_gen)		||
 	    put_user(buffer->bs_projid,	  &p32->bs_projid)	||
+	    put_user(buffer->bs_projid_hi,	&p32->bs_projid_hi)	||
 	    put_user(buffer->bs_dmevmask, &p32->bs_dmevmask)	||
 	    put_user(buffer->bs_dmstate,  &p32->bs_dmstate)	||
 	    put_user(buffer->bs_aextents, &p32->bs_aextents))
diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.h b/fs/xfs/linux-2.6/xfs_ioctl32.h
index 1024c4f..08b6057 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl32.h
+++ b/fs/xfs/linux-2.6/xfs_ioctl32.h
@@ -65,8 +65,10 @@
 	__s32		bs_extsize;	/* extent size			*/
 	__s32		bs_extents;	/* number of extents		*/
 	__u32		bs_gen;		/* generation count		*/
-	__u16		bs_projid;	/* project id			*/
-	unsigned char	bs_pad[14];	/* pad space, unused		*/
+	__u16		bs_projid_lo;	/* lower part of project id	*/
+#define	bs_projid	bs_projid_lo	/* (previously just bs_projid)	*/
+	__u16		bs_projid_hi;	/* high part of project id	*/
+	unsigned char	bs_pad[12];	/* pad space, unused		*/
 	__u32		bs_dmevmask;	/* DMIG event mask		*/
 	__u16		bs_dmstate;	/* DMIG state info		*/
 	__u16		bs_aextents;	/* attribute number of extents	*/
diff --git a/fs/xfs/linux-2.6/xfs_linux.h b/fs/xfs/linux-2.6/xfs_linux.h
index 76ebc58..214ddd7 100644
--- a/fs/xfs/linux-2.6/xfs_linux.h
+++ b/fs/xfs/linux-2.6/xfs_linux.h
@@ -143,7 +143,7 @@
 #define SYNCHRONIZE()	barrier()
 #define __return_address __builtin_return_address(0)
 
-#define dfltprid	0
+#define XFS_PROJID_DEFAULT	0
 #define MAXPATHLEN	1024
 
 #define MIN(a,b)	(min(a,b))
diff --git a/fs/xfs/quota/xfs_qm.c b/fs/xfs/quota/xfs_qm.c
index d109cc5..f8e854b 100644
--- a/fs/xfs/quota/xfs_qm.c
+++ b/fs/xfs/quota/xfs_qm.c
@@ -835,7 +835,7 @@
 			xfs_qm_dqattach_one(ip, ip->i_d.di_gid, XFS_DQ_GROUP,
 						flags & XFS_QMOPT_DQALLOC,
 						ip->i_udquot, &ip->i_gdquot) :
-			xfs_qm_dqattach_one(ip, ip->i_d.di_projid, XFS_DQ_PROJ,
+			xfs_qm_dqattach_one(ip, xfs_get_projid(ip), XFS_DQ_PROJ,
 						flags & XFS_QMOPT_DQALLOC,
 						ip->i_udquot, &ip->i_gdquot);
 		/*
@@ -1630,7 +1630,7 @@
 	}
 
 	if (XFS_IS_PQUOTA_ON(mp)) {
-		error = xfs_qm_quotacheck_dqadjust(ip, ip->i_d.di_projid,
+		error = xfs_qm_quotacheck_dqadjust(ip, xfs_get_projid(ip),
 						   XFS_DQ_PROJ, nblks, rtblks);
 		if (error)
 			goto error0;
@@ -2249,7 +2249,7 @@
 			xfs_dqunlock(gq);
 		}
 	} else if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp)) {
-		if (ip->i_d.di_projid != prid) {
+		if (xfs_get_projid(ip) != prid) {
 			xfs_iunlock(ip, lockflags);
 			if ((error = xfs_qm_dqget(mp, NULL, (xfs_dqid_t)prid,
 						 XFS_DQ_PROJ,
@@ -2371,7 +2371,7 @@
 	}
 	if (XFS_IS_OQUOTA_ON(ip->i_mount) && gdqp) {
 		if (XFS_IS_PQUOTA_ON(ip->i_mount) &&
-		     ip->i_d.di_projid != be32_to_cpu(gdqp->q_core.d_id))
+		     xfs_get_projid(ip) != be32_to_cpu(gdqp->q_core.d_id))
 			prjflags = XFS_QMOPT_ENOSPC;
 
 		if (prjflags ||
@@ -2475,7 +2475,7 @@
 		ip->i_gdquot = gdqp;
 		ASSERT(XFS_IS_OQUOTA_ON(mp));
 		ASSERT((XFS_IS_GQUOTA_ON(mp) ?
-			ip->i_d.di_gid : ip->i_d.di_projid) ==
+			ip->i_d.di_gid : xfs_get_projid(ip)) ==
 				be32_to_cpu(gdqp->q_core.d_id));
 		xfs_trans_mod_dquot(tp, gdqp, XFS_TRANS_DQ_ICOUNT, 1);
 	}
diff --git a/fs/xfs/quota/xfs_qm_bhv.c b/fs/xfs/quota/xfs_qm_bhv.c
index bea02d7..45b5cb1 100644
--- a/fs/xfs/quota/xfs_qm_bhv.c
+++ b/fs/xfs/quota/xfs_qm_bhv.c
@@ -81,7 +81,7 @@
 	xfs_mount_t		*mp = ip->i_mount;
 	xfs_dquot_t		*dqp;
 
-	if (!xfs_qm_dqget(mp, NULL, ip->i_d.di_projid, XFS_DQ_PROJ, 0, &dqp)) {
+	if (!xfs_qm_dqget(mp, NULL, xfs_get_projid(ip), XFS_DQ_PROJ, 0, &dqp)) {
 		xfs_fill_statvfs_from_dquot(statp, &dqp->q_core);
 		xfs_qm_dqput(dqp);
 	}
diff --git a/fs/xfs/quota/xfs_qm_syscalls.c b/fs/xfs/quota/xfs_qm_syscalls.c
index 5784743..bdebc18 100644
--- a/fs/xfs/quota/xfs_qm_syscalls.c
+++ b/fs/xfs/quota/xfs_qm_syscalls.c
@@ -1165,7 +1165,7 @@
 	}
 	xfs_qm_internalqcheck_get_dquots(mp,
 					(xfs_dqid_t) ip->i_d.di_uid,
-					(xfs_dqid_t) ip->i_d.di_projid,
+					(xfs_dqid_t) xfs_get_projid(ip),
 					(xfs_dqid_t) ip->i_d.di_gid,
 					&ud, &gd);
 	if (XFS_IS_UQUOTA_ON(mp)) {
diff --git a/fs/xfs/xfs_dinode.h b/fs/xfs/xfs_dinode.h
index e5b153b..dffba9b 100644
--- a/fs/xfs/xfs_dinode.h
+++ b/fs/xfs/xfs_dinode.h
@@ -49,8 +49,9 @@
 	__be32		di_uid;		/* owner's user id */
 	__be32		di_gid;		/* owner's group id */
 	__be32		di_nlink;	/* number of links to file */
-	__be16		di_projid;	/* owner's project id */
-	__u8		di_pad[8];	/* unused, zeroed space */
+	__be16		di_projid_lo;	/* lower part of owner's project id */
+	__be16		di_projid_hi;	/* higher part owner's project id */
+	__u8		di_pad[6];	/* unused, zeroed space */
 	__be16		di_flushiter;	/* incremented on flush */
 	xfs_timestamp_t	di_atime;	/* time last accessed */
 	xfs_timestamp_t	di_mtime;	/* time last modified */
diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
index 10f6093..8f6fc1a 100644
--- a/fs/xfs/xfs_fs.h
+++ b/fs/xfs/xfs_fs.h
@@ -293,9 +293,11 @@
 	__s32		bs_extsize;	/* extent size			*/
 	__s32		bs_extents;	/* number of extents		*/
 	__u32		bs_gen;		/* generation count		*/
-	__u16		bs_projid;	/* project id			*/
+	__u16		bs_projid_lo;	/* lower part of project id	*/
+#define	bs_projid	bs_projid_lo	/* (previously just bs_projid)	*/
 	__u16		bs_forkoff;	/* inode fork offset in bytes	*/
-	unsigned char	bs_pad[12];	/* pad space, unused		*/
+	__u16		bs_projid_hi;	/* higher part of project id	*/
+	unsigned char	bs_pad[10];	/* pad space, unused		*/
 	__u32		bs_dmevmask;	/* DMIG event mask		*/
 	__u16		bs_dmstate;	/* DMIG state info		*/
 	__u16		bs_aextents;	/* attribute number of extents	*/
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 493d6b0..108c7a0 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -660,7 +660,8 @@
 	to->di_uid = be32_to_cpu(from->di_uid);
 	to->di_gid = be32_to_cpu(from->di_gid);
 	to->di_nlink = be32_to_cpu(from->di_nlink);
-	to->di_projid = be16_to_cpu(from->di_projid);
+	to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
+	to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
 	memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
 	to->di_flushiter = be16_to_cpu(from->di_flushiter);
 	to->di_atime.t_sec = be32_to_cpu(from->di_atime.t_sec);
@@ -695,7 +696,8 @@
 	to->di_uid = cpu_to_be32(from->di_uid);
 	to->di_gid = cpu_to_be32(from->di_gid);
 	to->di_nlink = cpu_to_be32(from->di_nlink);
-	to->di_projid = cpu_to_be16(from->di_projid);
+	to->di_projid_lo = cpu_to_be16(from->di_projid_lo);
+	to->di_projid_hi = cpu_to_be16(from->di_projid_hi);
 	memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
 	to->di_flushiter = cpu_to_be16(from->di_flushiter);
 	to->di_atime.t_sec = cpu_to_be32(from->di_atime.t_sec);
@@ -874,7 +876,7 @@
 	if (ip->i_d.di_version == 1) {
 		ip->i_d.di_nlink = ip->i_d.di_onlink;
 		ip->i_d.di_onlink = 0;
-		ip->i_d.di_projid = 0;
+		xfs_set_projid(ip, 0);
 	}
 
 	ip->i_delayed_blks = 0;
@@ -982,7 +984,7 @@
 	mode_t		mode,
 	xfs_nlink_t	nlink,
 	xfs_dev_t	rdev,
-	xfs_prid_t	prid,
+	prid_t		prid,
 	int		okalloc,
 	xfs_buf_t	**ialloc_context,
 	boolean_t	*call_again,
@@ -1026,7 +1028,7 @@
 	ASSERT(ip->i_d.di_nlink == nlink);
 	ip->i_d.di_uid = current_fsuid();
 	ip->i_d.di_gid = current_fsgid();
-	ip->i_d.di_projid = prid;
+	xfs_set_projid(ip, prid);
 	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
 
 	/*
@@ -3007,7 +3009,7 @@
 			memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
 			memset(&(dip->di_pad[0]), 0,
 			      sizeof(dip->di_pad));
-			ASSERT(ip->i_d.di_projid == 0);
+			ASSERT(xfs_get_projid(ip) == 0);
 		}
 	}
 
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index ac82327..fac5229 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -134,8 +134,9 @@
 	__uint32_t	di_uid;		/* owner's user id */
 	__uint32_t	di_gid;		/* owner's group id */
 	__uint32_t	di_nlink;	/* number of links to file */
-	__uint16_t	di_projid;	/* owner's project id */
-	__uint8_t	di_pad[8];	/* unused, zeroed space */
+	__uint16_t	di_projid_lo;	/* lower part of owner's project id */
+	__uint16_t	di_projid_hi;	/* higher part of owner's project id */
+	__uint8_t	di_pad[6];	/* unused, zeroed space */
 	__uint16_t	di_flushiter;	/* incremented on flush */
 	xfs_ictimestamp_t di_atime;	/* time last accessed */
 	xfs_ictimestamp_t di_mtime;	/* time last modified */
@@ -334,6 +335,25 @@
 }
 
 /*
+ * Project quota id helpers (previously projid was 16bit only
+ * and using two 16bit values to hold new 32bit projid was choosen
+ * to retain compatibility with "old" filesystems).
+ */
+static inline prid_t
+xfs_get_projid(struct xfs_inode *ip)
+{
+	return (prid_t)ip->i_d.di_projid_hi << 16 | ip->i_d.di_projid_lo;
+}
+
+static inline void
+xfs_set_projid(struct xfs_inode *ip,
+		prid_t projid)
+{
+	ip->i_d.di_projid_hi = (__uint16_t) (projid >> 16);
+	ip->i_d.di_projid_lo = (__uint16_t) (projid & 0xffff);
+}
+
+/*
  * Manage the i_flush queue embedded in the inode.  This completion
  * queue synchronizes processes attempting to flush the in-core
  * inode back to disk.
@@ -455,7 +475,7 @@
  * xfs_inode.c prototypes.
  */
 int		xfs_ialloc(struct xfs_trans *, xfs_inode_t *, mode_t,
-			   xfs_nlink_t, xfs_dev_t, xfs_prid_t, int,
+			   xfs_nlink_t, xfs_dev_t, prid_t, int,
 			   struct xfs_buf **, boolean_t *, xfs_inode_t **);
 
 uint		xfs_ip2xflags(struct xfs_inode *);
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index 7e3626e..dc1882a 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -92,7 +92,8 @@
 	 * further change.
 	 */
 	buf->bs_nlink = dic->di_nlink;
-	buf->bs_projid = dic->di_projid;
+	buf->bs_projid_lo = dic->di_projid_lo;
+	buf->bs_projid_hi = dic->di_projid_hi;
 	buf->bs_ino = ino;
 	buf->bs_mode = dic->di_mode;
 	buf->bs_uid = dic->di_uid;
diff --git a/fs/xfs/xfs_rename.c b/fs/xfs/xfs_rename.c
index 9028733..d2af0a8 100644
--- a/fs/xfs/xfs_rename.c
+++ b/fs/xfs/xfs_rename.c
@@ -183,7 +183,7 @@
 	 * tree quota mechanism would be circumvented.
 	 */
 	if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
-		     (target_dp->i_d.di_projid != src_ip->i_d.di_projid))) {
+		     (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
 		error = XFS_ERROR(EXDEV);
 		goto error_return;
 	}
diff --git a/fs/xfs/xfs_sb.h b/fs/xfs/xfs_sb.h
index 1b017c6..1eb2ba5 100644
--- a/fs/xfs/xfs_sb.h
+++ b/fs/xfs/xfs_sb.h
@@ -80,10 +80,12 @@
 #define XFS_SB_VERSION2_RESERVED4BIT	0x00000004
 #define XFS_SB_VERSION2_ATTR2BIT	0x00000008	/* Inline attr rework */
 #define XFS_SB_VERSION2_PARENTBIT	0x00000010	/* parent pointers */
+#define XFS_SB_VERSION2_PROJID32BIT	0x00000080	/* 32 bit project id */
 
 #define	XFS_SB_VERSION2_OKREALFBITS	\
 	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
-	 XFS_SB_VERSION2_ATTR2BIT)
+	 XFS_SB_VERSION2_ATTR2BIT	| \
+	 XFS_SB_VERSION2_PROJID32BIT)
 #define	XFS_SB_VERSION2_OKSASHFBITS	\
 	(0)
 #define XFS_SB_VERSION2_OKREALBITS	\
@@ -495,6 +497,12 @@
 		sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT;
 }
 
+static inline int xfs_sb_version_hasprojid32bit(xfs_sb_t *sbp)
+{
+	return xfs_sb_version_hasmorebits(sbp) &&
+		(sbp->sb_features2 & XFS_SB_VERSION2_PROJID32BIT);
+}
+
 /*
  * end of superblock version macros
  */
diff --git a/fs/xfs/xfs_types.h b/fs/xfs/xfs_types.h
index 3207752..26d1867 100644
--- a/fs/xfs/xfs_types.h
+++ b/fs/xfs/xfs_types.h
@@ -73,8 +73,6 @@
 typedef	__uint32_t	xfs_dablk_t;	/* dir/attr block number (in file) */
 typedef	__uint32_t	xfs_dahash_t;	/* dir/attr hash value */
 
-typedef __uint16_t	xfs_prid_t;	/* prid_t truncated to 16bits in XFS */
-
 typedef __uint32_t	xlog_tid_t;	/* transaction ID type */
 
 /*
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index f4195f6..8e4a63c 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -114,7 +114,7 @@
 		 */
 		ASSERT(udqp == NULL);
 		ASSERT(gdqp == NULL);
-		code = xfs_qm_vop_dqalloc(ip, uid, gid, ip->i_d.di_projid,
+		code = xfs_qm_vop_dqalloc(ip, uid, gid, xfs_get_projid(ip),
 					 qflags, &udqp, &gdqp);
 		if (code)
 			return code;
@@ -1268,7 +1268,7 @@
 	boolean_t		unlock_dp_on_error = B_FALSE;
 	uint			cancel_flags;
 	int			committed;
-	xfs_prid_t		prid;
+	prid_t			prid;
 	struct xfs_dquot	*udqp = NULL;
 	struct xfs_dquot	*gdqp = NULL;
 	uint			resblks;
@@ -1281,9 +1281,9 @@
 		return XFS_ERROR(EIO);
 
 	if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
-		prid = dp->i_d.di_projid;
+		prid = xfs_get_projid(dp);
 	else
-		prid = dfltprid;
+		prid = XFS_PROJID_DEFAULT;
 
 	/*
 	 * Make sure that we have allocated dquot(s) on disk.
@@ -1882,7 +1882,7 @@
 	 * the tree quota mechanism could be circumvented.
 	 */
 	if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
-		     (tdp->i_d.di_projid != sip->i_d.di_projid))) {
+		     (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
 		error = XFS_ERROR(EXDEV);
 		goto error_return;
 	}
@@ -1956,7 +1956,7 @@
 	int			byte_cnt;
 	int			n;
 	xfs_buf_t		*bp;
-	xfs_prid_t		prid;
+	prid_t			prid;
 	struct xfs_dquot	*udqp, *gdqp;
 	uint			resblks;
 
@@ -1979,9 +1979,9 @@
 
 	udqp = gdqp = NULL;
 	if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
-		prid = dp->i_d.di_projid;
+		prid = xfs_get_projid(dp);
 	else
-		prid = (xfs_prid_t)dfltprid;
+		prid = XFS_PROJID_DEFAULT;
 
 	/*
 	 * Make sure that we have allocated dquot(s) on disk.