2 files changed, 12 insertions, 3 deletions

diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index dab5d3802374..003e5f29d684 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -659,9 +659,17 @@ xfs_fs_sync_super(
         int                     error;
         int                     flags;
 
-        if (unlikely(sb->s_frozen == SB_FREEZE_WRITE))
-                flags = SYNC_QUIESCE;
-        else
+        if (unlikely(sb->s_frozen == SB_FREEZE_WRITE)) {
+                /*
+                 * First stage of freeze - no more writers will make progress
+                 * now we are here, so we flush delwri and delalloc buffers
+                 * here, then wait for all I/O to complete.  Data is frozen at
+                 * that point. Metadata is not frozen, transactions can still
+                 * occur here so don't bother flushing the buftarg (i.e
+                 * SYNC_QUIESCE) because it'll just get dirty again.
+                 */
+                flags = SYNC_FSDATA | SYNC_DELWRI | SYNC_WAIT | SYNC_DIO_WAIT;
+        } else
                 flags = SYNC_FSDATA | (wait ? SYNC_WAIT : 0);
 
         error = bhv_vfs_sync(vfsp, flags, NULL);
diff --git a/fs/xfs/linux-2.6/xfs_vfs.h b/fs/xfs/linux-2.6/xfs_vfs.h
index da255bdf5260..558823a83065 100644
--- a/fs/xfs/linux-2.6/xfs_vfs.h
+++ b/fs/xfs/linux-2.6/xfs_vfs.h
@@ -92,6 +92,7 @@ typedef enum {
 #define SYNC_REFCACHE           0x0040  /* prune some of the nfs ref cache */
 #define SYNC_REMOUNT            0x0080  /* remount readonly, no dummy LRs */
 #define SYNC_QUIESCE            0x0100  /* quiesce fileystem for a snapshot */
+#define SYNC_DIO_WAIT           0x0200  /* wait for direct I/O to complete */
 
 #define SHUTDOWN_META_IO_ERROR  0x0001  /* write attempt to metadata failed */
 #define SHUTDOWN_LOG_IO_ERROR   0x0002  /* write attempt to the log failed */