1 files changed, 28 insertions, 17 deletions

diff --git a/fs/xfs/xfs_vfsops.c b/fs/xfs/xfs_vfsops.c
index 62336a4cc5a4..29f72f613782 100644
--- a/fs/xfs/xfs_vfsops.c
+++ b/fs/xfs/xfs_vfsops.c
@@ -640,7 +640,7 @@ xfs_quiesce_fs(
          * we can write the unmount record.
          */
         do {
-                xfs_syncsub(mp, SYNC_REMOUNT|SYNC_ATTR|SYNC_WAIT, 0, NULL);
+                xfs_syncsub(mp, SYNC_REMOUNT|SYNC_ATTR|SYNC_WAIT, NULL);
                 pincount = xfs_flush_buftarg(mp->m_ddev_targp, 1);
                 if (!pincount) {
                         delay(50);
@@ -806,7 +806,7 @@ xfs_statvfs(
 
         statp->f_type = XFS_SB_MAGIC;
 
-        xfs_icsb_sync_counters_lazy(mp);
+        xfs_icsb_sync_counters_flags(mp, XFS_ICSB_LAZY_COUNT);
         s = XFS_SB_LOCK(mp);
         statp->f_bsize = sbp->sb_blocksize;
         lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
@@ -872,6 +872,10 @@ xfs_statvfs(
  *                     this by simply making sure the log gets flushed
  *                     if SYNC_BDFLUSH is set, and by actually writing it
  *                     out otherwise.
+ *      SYNC_IOWAIT  - The caller wants us to wait for all data I/O to complete
+ *                     before we return (including direct I/O). Forms the drain
+ *                     side of the write barrier needed to safely quiesce the
+ *                     filesystem.
  *
  */
 /*ARGSUSED*/
@@ -883,27 +887,20 @@ xfs_sync(
 {
         xfs_mount_t     *mp = XFS_BHVTOM(bdp);
 
-        if (unlikely(flags == SYNC_QUIESCE))
-                return xfs_quiesce_fs(mp);
-        else
-                return xfs_syncsub(mp, flags, 0, NULL);
+        return xfs_syncsub(mp, flags, NULL);
 }
 
 /*
  * xfs sync routine for internal use
  *
  * This routine supports all of the flags defined for the generic vfs_sync
- * interface as explained above under xfs_sync.  In the interests of not
- * changing interfaces within the 6.5 family, additional internally-
- * required functions are specified within a separate xflags parameter,
- * only available by calling this routine.
+ * interface as explained above under xfs_sync.
  *
  */
 int
 xfs_sync_inodes(
         xfs_mount_t     *mp,
         int             flags,
-        int             xflags,
         int             *bypassed)
 {
         xfs_inode_t     *ip = NULL;
@@ -1176,6 +1173,13 @@ xfs_sync_inodes(
                         }
 
                 }
+                /*
+                 * When freezing, we need to wait ensure all I/O (including direct
+                 * I/O) is complete to ensure no further data modification can take
+                 * place after this point
+                 */
+                if (flags & SYNC_IOWAIT)
+                        vn_iowait(vp);
 
                 if (flags & SYNC_BDFLUSH) {
                         if ((flags & SYNC_ATTR) &&
@@ -1412,17 +1416,13 @@ xfs_sync_inodes(
  * xfs sync routine for internal use
  *
  * This routine supports all of the flags defined for the generic vfs_sync
- * interface as explained above under xfs_sync.  In the interests of not
- * changing interfaces within the 6.5 family, additional internally-
- * required functions are specified within a separate xflags parameter,
- * only available by calling this routine.
+ * interface as explained above under xfs_sync.
  *
  */
 int
 xfs_syncsub(
         xfs_mount_t     *mp,
         int             flags,
-        int             xflags,
         int             *bypassed)
 {
         int             error = 0;
@@ -1444,7 +1444,7 @@ xfs_syncsub(
                 if (flags & SYNC_BDFLUSH)
                         xfs_finish_reclaim_all(mp, 1);
                 else
-                        error = xfs_sync_inodes(mp, flags, xflags, bypassed);
+                        error = xfs_sync_inodes(mp, flags, bypassed);
         }
 
         /*
@@ -1958,15 +1958,26 @@ xfs_showargs(
         return 0;
 }
 
+/*
+ * Second stage of a freeze. The data is already frozen, now we have to take
+ * care of the metadata. New transactions are already blocked, so we need to
+ * wait for any remaining transactions to drain out before proceding.
+ */
 STATIC void
 xfs_freeze(
         bhv_desc_t      *bdp)
 {
         xfs_mount_t     *mp = XFS_BHVTOM(bdp);
 
+        /* wait for all modifications to complete */
         while (atomic_read(&mp->m_active_trans) > 0)
                 delay(100);
 
+        /* flush inodes and push all remaining buffers out to disk */
+        xfs_quiesce_fs(mp);
+
+        ASSERT_ALWAYS(atomic_read(&mp->m_active_trans) == 0);
+
         /* Push the superblock and write an unmount record */
         xfs_log_unmount_write(mp);
         xfs_unmountfs_writesb(mp);