Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / drivers / md / dm-snap.c

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index d73f17f..57f1bf7 100644 (file)
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -678,6 +678,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
        ti->private = s;
        ti->split_io = s->store->chunk_size;
+       ti->num_flush_requests = 1;
 
        return 0;
 
@@ -1030,6 +1031,11 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
        chunk_t chunk;
        struct dm_snap_pending_exception *pe = NULL;
 
+       if (unlikely(bio_empty_barrier(bio))) {
+               bio->bi_bdev = s->store->cow->bdev;
+               return DM_MAPIO_REMAPPED;
+       }
+
        chunk = sector_to_chunk(s->store, bio->bi_sector);
 
        /* Full snapshots are not usable */
@@ -1170,6 +1176,15 @@ static int snapshot_status(struct dm_target *ti, status_type_t type,
        return 0;
 }
 
+static int snapshot_iterate_devices(struct dm_target *ti,
+                                   iterate_devices_callout_fn fn, void *data)
+{
+       struct dm_snapshot *snap = ti->private;
+
+       return fn(ti, snap->origin, 0, ti->len, data);
+}
+
+
 /*-----------------------------------------------------------------
  * Origin methods
  *---------------------------------------------------------------*/
@@ -1338,6 +1353,8 @@ static int origin_ctr(struct dm_target *ti, unsigned int argc, char **argv)
        }
 
        ti->private = dev;
+       ti->num_flush_requests = 1;
+
        return 0;
 }
 
@@ -1353,6 +1370,9 @@ static int origin_map(struct dm_target *ti, struct bio *bio,
        struct dm_dev *dev = ti->private;
        bio->bi_bdev = dev->bdev;
 
+       if (unlikely(bio_empty_barrier(bio)))
+               return DM_MAPIO_REMAPPED;
+
        /* Only tell snapshots if this is a write */
        return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : DM_MAPIO_REMAPPED;
 }
@@ -1399,20 +1419,29 @@ static int origin_status(struct dm_target *ti, status_type_t type, char *result,
        return 0;
 }
 
+static int origin_iterate_devices(struct dm_target *ti,
+                                 iterate_devices_callout_fn fn, void *data)
+{
+       struct dm_dev *dev = ti->private;
+
+       return fn(ti, dev, 0, ti->len, data);
+}
+
 static struct target_type origin_target = {
        .name    = "snapshot-origin",
-       .version = {1, 6, 0},
+       .version = {1, 7, 0},
        .module  = THIS_MODULE,
        .ctr     = origin_ctr,
        .dtr     = origin_dtr,
        .map     = origin_map,
        .resume  = origin_resume,
        .status  = origin_status,
+       .iterate_devices = origin_iterate_devices,
 };
 
 static struct target_type snapshot_target = {
        .name    = "snapshot",
-       .version = {1, 6, 0},
+       .version = {1, 7, 0},
        .module  = THIS_MODULE,
        .ctr     = snapshot_ctr,
        .dtr     = snapshot_dtr,
@@ -1420,6 +1449,7 @@ static struct target_type snapshot_target = {
        .end_io  = snapshot_end_io,
        .resume  = snapshot_resume,
        .status  = snapshot_status,
+       .iterate_devices = snapshot_iterate_devices,
 };
 
 static int __init dm_snapshot_init(void)