diff --git a/fs/xfs/xfs_clnt.h b/fs/xfs/xfs_clnt.h
index 1fbe2bf..328a528 100644
--- a/fs/xfs/xfs_clnt.h
+++ b/fs/xfs/xfs_clnt.h
@@ -41,6 +41,7 @@
  */
 struct xfs_mount_args {
 	int	flags;		/* flags -> see XFSMNT_... macros below */
+	int	flags2;		/* flags -> see XFSMNT2_... macros below */
 	int	logbufs;	/* Number of log buffers, -1 to default */
 	int	logbufsize;	/* Size of log buffers, -1 to default */
 	char	fsname[MAXNAMELEN+1];	/* data device name */
@@ -54,7 +55,7 @@
 };
 
 /*
- * XFS mount option flags
+ * XFS mount option flags -- args->flags1
  */
 #define	XFSMNT_COMPAT_ATTR	0x00000001	/* do not use ATTR2 format */
 #define	XFSMNT_WSYNC		0x00000002	/* safe mode nfs mount
@@ -77,7 +78,7 @@
 #define XFSMNT_SHARED		0x00001000	/* shared XFS mount */
 #define XFSMNT_IOSIZE		0x00002000	/* optimize for I/O size */
 #define XFSMNT_OSYNCISOSYNC	0x00004000	/* o_sync is REALLY o_sync */
-						/* (osyncisdsync is now default) */
+						/* (osyncisdsync is default) */
 #define XFSMNT_32BITINODES	0x00200000	/* restrict inodes to 32
 						 * bits of address space */
 #define XFSMNT_GQUOTA		0x00400000	/* group quota accounting */
@@ -92,7 +93,12 @@
 #define XFSMNT_IHASHSIZE	0x20000000	/* inode hash table size */
 #define XFSMNT_DIRSYNC		0x40000000	/* sync creat,link,unlink,rename
 						 * symlink,mkdir,rmdir,mknod */
-#define XFSMNT_COMPAT_IOSIZE	0x80000000	/* don't report large preferred
-						 * I/O size in stat() */
+#define XFSMNT_FLAGS2		0x80000000	/* more flags set in flags2 */
+
+/*
+ * XFS mount option flags -- args->flags2
+ */
+#define XFSMNT2_COMPAT_IOSIZE	0x00000001	/* don't report large preferred
+						 * I/O size in stat(2) */
 
 #endif	/* __XFS_CLNT_H__ */
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 04f8e37..f724a2b 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -333,7 +333,7 @@
 	sema_t			m_growlock;	/* growfs mutex */
 	int			m_fixedfsid[2];	/* unchanged for life of FS */
 	uint			m_dmevmask;	/* DMI events for this FS */
-	uint			m_flags;	/* global mount flags */
+	__uint64_t		m_flags;	/* global mount flags */
 	uint			m_attroffset;	/* inode attribute offset */
 	uint			m_dir_node_ents; /* #entries in a dir danode */
 	uint			m_attr_node_ents; /* #entries in attr danode */
@@ -378,39 +378,39 @@
 /*
  * Flags for m_flags.
  */
-#define	XFS_MOUNT_WSYNC		0x00000001	/* for nfs - all metadata ops
+#define	XFS_MOUNT_WSYNC		(1ULL << 0)	/* for nfs - all metadata ops
 						   must be synchronous except
 						   for space allocations */
-#define	XFS_MOUNT_INO64		0x00000002
-			     /* 0x00000004	-- currently unused */
-			     /* 0x00000008	-- currently unused */
-#define XFS_MOUNT_FS_SHUTDOWN	0x00000010	/* atomic stop of all filesystem
+#define	XFS_MOUNT_INO64		(1ULL << 1)
+			     /* (1ULL << 2)	-- currently unused */
+			     /* (1ULL << 3)	-- currently unused */
+#define XFS_MOUNT_FS_SHUTDOWN	(1ULL << 4)	/* atomic stop of all filesystem
 						   operations, typically for
 						   disk errors in metadata */
-#define XFS_MOUNT_NOATIME	0x00000020	/* don't modify inode access
+#define XFS_MOUNT_NOATIME	(1ULL << 5)	/* don't modify inode access
 						   times on reads */
-#define XFS_MOUNT_RETERR	0x00000040      /* return alignment errors to
+#define XFS_MOUNT_RETERR	(1ULL << 6)     /* return alignment errors to
 						   user */
-#define XFS_MOUNT_NOALIGN	0x00000080	/* turn off stripe alignment
+#define XFS_MOUNT_NOALIGN	(1ULL << 7)	/* turn off stripe alignment
 						   allocations */
-#define XFS_MOUNT_COMPAT_ATTR	0x00000100	/* do not use attr2 format */
-			     /*	0x00000200	-- currently unused */
-#define XFS_MOUNT_NORECOVERY	0x00000400	/* no recovery - dirty fs */
-#define XFS_MOUNT_SHARED	0x00000800	/* shared mount */
-#define XFS_MOUNT_DFLT_IOSIZE	0x00001000	/* set default i/o size */
-#define XFS_MOUNT_OSYNCISOSYNC	0x00002000	/* o_sync is REALLY o_sync */
+#define XFS_MOUNT_COMPAT_ATTR	(1ULL << 8)	/* do not use attr2 format */
+			     /*	(1ULL << 9)	-- currently unused */
+#define XFS_MOUNT_NORECOVERY	(1ULL << 10)	/* no recovery - dirty fs */
+#define XFS_MOUNT_SHARED	(1ULL << 11)	/* shared mount */
+#define XFS_MOUNT_DFLT_IOSIZE	(1ULL << 12)	/* set default i/o size */
+#define XFS_MOUNT_OSYNCISOSYNC	(1ULL << 13)	/* o_sync is REALLY o_sync */
 						/* osyncisdsync is now default*/
-#define XFS_MOUNT_32BITINODES	0x00004000	/* do not create inodes above
+#define XFS_MOUNT_32BITINODES	(1ULL << 14)	/* do not create inodes above
 						 * 32 bits in size */
-#define XFS_MOUNT_32BITINOOPT	0x00008000	/* saved mount option state */
-#define XFS_MOUNT_NOUUID	0x00010000	/* ignore uuid during mount */
-#define XFS_MOUNT_BARRIER	0x00020000
-#define XFS_MOUNT_IDELETE	0x00040000	/* delete empty inode clusters*/
-#define XFS_MOUNT_SWALLOC	0x00080000	/* turn on stripe width
+#define XFS_MOUNT_32BITINOOPT	(1ULL << 15)	/* saved mount option state */
+#define XFS_MOUNT_NOUUID	(1ULL << 16)	/* ignore uuid during mount */
+#define XFS_MOUNT_BARRIER	(1ULL << 17)
+#define XFS_MOUNT_IDELETE	(1ULL << 18)	/* delete empty inode clusters*/
+#define XFS_MOUNT_SWALLOC	(1ULL << 19)	/* turn on stripe width
 						 * allocation */
-#define XFS_MOUNT_IHASHSIZE	0x00100000	/* inode hash table size */
-#define XFS_MOUNT_DIRSYNC	0x00200000	/* synchronous directory ops */
-#define XFS_MOUNT_COMPAT_IOSIZE	0x00400000	/* don't report large preferred
+#define XFS_MOUNT_IHASHSIZE	(1ULL << 20)	/* inode hash table size */
+#define XFS_MOUNT_DIRSYNC	(1ULL << 21)	/* synchronous directory ops */
+#define XFS_MOUNT_COMPAT_IOSIZE	(1ULL << 22)	/* don't report large preferred
 						 * I/O size in stat() */
 
 
diff --git a/fs/xfs/xfs_vfsops.c b/fs/xfs/xfs_vfsops.c
index 96f7cde..f4f8805 100644
--- a/fs/xfs/xfs_vfsops.c
+++ b/fs/xfs/xfs_vfsops.c
@@ -291,11 +291,12 @@
 		mp->m_flags |= XFS_MOUNT_IDELETE;
 	if (ap->flags & XFSMNT_DIRSYNC)
 		mp->m_flags |= XFS_MOUNT_DIRSYNC;
-	if (ap->flags & XFSMNT_COMPAT_IOSIZE)
-		mp->m_flags |= XFS_MOUNT_COMPAT_IOSIZE;
 	if (ap->flags & XFSMNT_COMPAT_ATTR)
 		mp->m_flags |= XFS_MOUNT_COMPAT_ATTR;
 
+	if (ap->flags2 & XFSMNT2_COMPAT_IOSIZE)
+		mp->m_flags |= XFS_MOUNT_COMPAT_IOSIZE;
+
 	/*
 	 * no recovery flag requires a read-only mount
 	 */
@@ -1679,7 +1680,7 @@
 	int			dsunit, dswidth, vol_dsunit, vol_dswidth;
 	int			iosize;
 
-	args->flags |= XFSMNT_COMPAT_IOSIZE;
+	args->flags2 |= XFSMNT2_COMPAT_IOSIZE;
 	args->flags |= XFSMNT_COMPAT_ATTR;
 
 #if 0	/* XXX: off by default, until some remaining issues ironed out */
@@ -1811,9 +1812,9 @@
 		} else if (!strcmp(this_char, MNTOPT_NOIKEEP)) {
 			args->flags |= XFSMNT_IDELETE;
 		} else if (!strcmp(this_char, MNTOPT_LARGEIO)) {
-			args->flags &= ~XFSMNT_COMPAT_IOSIZE;
+			args->flags2 &= ~XFSMNT2_COMPAT_IOSIZE;
 		} else if (!strcmp(this_char, MNTOPT_NOLARGEIO)) {
-			args->flags |= XFSMNT_COMPAT_IOSIZE;
+			args->flags2 |= XFSMNT2_COMPAT_IOSIZE;
 		} else if (!strcmp(this_char, MNTOPT_ATTR2)) {
 			args->flags &= ~XFSMNT_COMPAT_ATTR;
 		} else if (!strcmp(this_char, MNTOPT_NOATTR2)) {
@@ -1867,6 +1868,8 @@
 		args->sunit = args->swidth = 0;
 	}
 
+	if (args->flags2)
+		args->flags |= XFSMNT_FLAGS2;
 	return 0;
 }