dm stripe: add WRITE SAME support
Mike Snitzer [Fri, 21 Dec 2012 20:23:41 +0000 (20:23 +0000)]
Rename stripe_map_discard to stripe_map_range and reuse it for WRITE
SAME bio processing.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

drivers/md/dm-stripe.c

index 6b0e5ea..c89cde8 100644 (file)
@@ -162,6 +162,7 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
        ti->num_flush_requests = stripes;
        ti->num_discard_requests = stripes;
+       ti->num_write_same_requests = stripes;
 
        sc->chunk_size = chunk_size;
        if (chunk_size & (chunk_size - 1))
@@ -251,8 +252,8 @@ static void stripe_map_range_sector(struct stripe_c *sc, sector_t sector,
                *result += sc->chunk_size;              /* next chunk */
 }
 
-static int stripe_map_discard(struct stripe_c *sc, struct bio *bio,
-                             uint32_t target_stripe)
+static int stripe_map_range(struct stripe_c *sc, struct bio *bio,
+                           uint32_t target_stripe)
 {
        sector_t begin, end;
 
@@ -283,10 +284,11 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)
                bio->bi_bdev = sc->stripe[target_request_nr].dev->bdev;
                return DM_MAPIO_REMAPPED;
        }
-       if (unlikely(bio->bi_rw & REQ_DISCARD)) {
+       if (unlikely(bio->bi_rw & REQ_DISCARD) ||
+           unlikely(bio->bi_rw & REQ_WRITE_SAME)) {
                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);
+               return stripe_map_range(sc, bio, target_request_nr);
        }
 
        stripe_map_sector(sc, bio->bi_sector, &stripe, &bio->bi_sector);