1 files changed, 25 insertions, 13 deletions

diff --git a/fs/xfs/xfs_vfsops.c b/fs/xfs/xfs_vfsops.c
index f1a904e23ade..8238c7517822 100644
--- a/fs/xfs/xfs_vfsops.c
+++ b/fs/xfs/xfs_vfsops.c
@@ -321,8 +321,8 @@ xfs_start_flags(
 
         if (ap->flags & XFSMNT_NOUUID)
                 mp->m_flags |= XFS_MOUNT_NOUUID;
-        if (ap->flags & XFSMNT_NOLOGFLUSH)
-                mp->m_flags |= XFS_MOUNT_NOLOGFLUSH;
+        if (ap->flags & XFSMNT_BARRIER)
+                mp->m_flags |= XFS_MOUNT_BARRIER;
 
         return 0;
 }
@@ -512,8 +512,14 @@ xfs_mount(
                 goto error2;
 
         error = XFS_IOINIT(vfsp, args, flags);
-        if (!error)
-                return 0;
+        if (error)
+                goto error2;
+
+        if ((args->flags & XFSMNT_BARRIER) &&
+            !(XFS_MTOVFS(mp)->vfs_flag & VFS_RDONLY))
+                xfs_mountfs_check_barriers(mp);
+        return 0;
+
 error2:
         if (mp->m_sb_bp)
                 xfs_freesb(mp);
@@ -656,19 +662,24 @@ xfs_mntupdate(
         else
                 mp->m_flags &= ~XFS_MOUNT_NOATIME;
 
-        if (!(vfsp->vfs_flag & VFS_RDONLY)) {
-                VFS_SYNC(vfsp, SYNC_FSDATA|SYNC_BDFLUSH|SYNC_ATTR, NULL, error);
+        if ((vfsp->vfs_flag & VFS_RDONLY) &&
+            !(*flags & MS_RDONLY)) {
+                vfsp->vfs_flag &= ~VFS_RDONLY;
+
+                if (args->flags & XFSMNT_BARRIER)
+                        xfs_mountfs_check_barriers(mp);
         }
 
-        if (*flags & MS_RDONLY) {
+        if (!(vfsp->vfs_flag & VFS_RDONLY) &&
+            (*flags & MS_RDONLY)) {
+                VFS_SYNC(vfsp, SYNC_FSDATA|SYNC_BDFLUSH|SYNC_ATTR, NULL, error);
+
                 xfs_quiesce_fs(mp);
 
                 /* Ok now write out an unmount record */
                 xfs_log_unmount_write(mp);
                 xfs_unmountfs_writesb(mp);
                 vfsp->vfs_flag |= VFS_RDONLY;
-        } else {
-                vfsp->vfs_flag &= ~VFS_RDONLY;
         }
 
         return 0;
@@ -1628,7 +1639,8 @@ xfs_vget(
 #define MNTOPT_ALLOCSIZE    "allocsize"    /* preferred allocation size */
 #define MNTOPT_IHASHSIZE    "ihashsize"    /* size of inode hash table */
 #define MNTOPT_NORECOVERY   "norecovery"   /* don't run XFS recovery */
-#define MNTOPT_NOLOGFLUSH   "nologflush"   /* don't hard flush on log writes */
+#define MNTOPT_BARRIER  "barrier"       /* use writer barriers for log write and
+                                           unwritten extent conversion */
 #define MNTOPT_OSYNCISOSYNC "osyncisosync" /* o_sync is REALLY o_sync */
 #define MNTOPT_64BITINODE   "inode64"   /* inodes can be allocated anywhere */
 #define MNTOPT_IKEEP    "ikeep"         /* do not free empty inode clusters */
@@ -1791,8 +1803,8 @@ xfs_parseargs(
 #endif
                 } else if (!strcmp(this_char, MNTOPT_NOUUID)) {
                         args->flags |= XFSMNT_NOUUID;
-                } else if (!strcmp(this_char, MNTOPT_NOLOGFLUSH)) {
-                        args->flags |= XFSMNT_NOLOGFLUSH;
+                } else if (!strcmp(this_char, MNTOPT_BARRIER)) {
+                        args->flags |= XFSMNT_BARRIER;
                 } else if (!strcmp(this_char, MNTOPT_IKEEP)) {
                         args->flags &= ~XFSMNT_IDELETE;
                 } else if (!strcmp(this_char, MNTOPT_NOIKEEP)) {
@@ -1866,7 +1878,7 @@ xfs_showargs(
                 { XFS_MOUNT_NOUUID,             "," MNTOPT_NOUUID },
                 { XFS_MOUNT_NORECOVERY,         "," MNTOPT_NORECOVERY },
                 { XFS_MOUNT_OSYNCISOSYNC,       "," MNTOPT_OSYNCISOSYNC },
-                { XFS_MOUNT_NOLOGFLUSH,         "," MNTOPT_NOLOGFLUSH },
+                { XFS_MOUNT_BARRIER,            "," MNTOPT_BARRIER },
                 { XFS_MOUNT_IDELETE,            "," MNTOPT_NOIKEEP },
                 { 0, NULL }
         };