dm: move target request nr to dm_target_io

This patch moves target_request_nr from map_info to dm_target_io and
makes it accessible with dm_bio_get_target_request_nr.

This patch is a preparation for the next patch that removes map_info.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

3 files changed, 5 insertions, 4 deletions

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 5e88bc437be0..b7e179cdc5af 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1682,7 +1682,7 @@ static int snapshot_merge_map(struct dm_target *ti, struct bio *bio,
         chunk_t chunk;
 
         if (bio->bi_rw & REQ_FLUSH) {
-                if (!map_context->target_request_nr)
+                if (!dm_bio_get_target_request_nr(bio))
                         bio->bi_bdev = s->origin->bdev;
                 else
                         bio->bi_bdev = s->cow->bdev;
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index e2f876539743..4e7ba82146c0 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -279,13 +279,13 @@ static int stripe_map(struct dm_target *ti, struct bio *bio,
         unsigned target_request_nr;
 
         if (bio->bi_rw & REQ_FLUSH) {
-                target_request_nr = map_context->target_request_nr;
+                target_request_nr = dm_bio_get_target_request_nr(bio);
                 BUG_ON(target_request_nr >= sc->stripes);
                 bio->bi_bdev = sc->stripe[target_request_nr].dev->bdev;
                 return DM_MAPIO_REMAPPED;
         }
         if (unlikely(bio->bi_rw & REQ_DISCARD)) {
-                target_request_nr = map_context->target_request_nr;
+                target_request_nr = dm_bio_get_target_request_nr(bio);
                 BUG_ON(target_request_nr >= sc->stripes);
                 return stripe_map_discard(sc, bio, target_request_nr);
         }
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 2765cf2ba0ff..5ee580b4f330 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1099,6 +1099,7 @@ static struct dm_target_io *alloc_tio(struct clone_info *ci,
         tio->io = ci->io;
         tio->ti = ti;
         memset(&tio->info, 0, sizeof(tio->info));
+        tio->target_request_nr = 0;
 
         return tio;
 }
@@ -1109,7 +1110,7 @@ static void __issue_target_request(struct clone_info *ci, struct dm_target *ti,
         struct dm_target_io *tio = alloc_tio(ci, ti, ci->bio->bi_max_vecs);
         struct bio *clone = &tio->clone;
 
-        tio->info.target_request_nr = request_nr;
+        tio->target_request_nr = request_nr;
 
         /*
          * Discard requests require the bio's inline iovecs be initialized.