dm stripe: move sector translation to a function

Move sector to stripe translation into a function.

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

1 files changed, 14 insertions, 7 deletions

diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 779f47a0fe71..e2ad1ae5268d 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -207,11 +207,20 @@ static void stripe_dtr(struct dm_target *ti)
         kfree(sc);
 }
 
+static void stripe_map_sector(struct stripe_c *sc, sector_t sector,
+                              uint32_t *stripe, sector_t *result)
+{
+        sector_t offset = dm_target_offset(sc->ti, sector);
+        sector_t chunk = offset >> sc->chunk_shift;
+
+        *stripe = sector_div(chunk, sc->stripes);
+        *result = (chunk << sc->chunk_shift) | (offset & sc->chunk_mask);
+}
+
 static int stripe_map(struct dm_target *ti, struct bio *bio,
                       union map_info *map_context)
 {
-        struct stripe_c *sc = (struct stripe_c *) ti->private;
-        sector_t offset, chunk;
+        struct stripe_c *sc = ti->private;
         uint32_t stripe;
         unsigned target_request_nr;
 
@@ -222,13 +231,11 @@ static int stripe_map(struct dm_target *ti, struct bio *bio,
                 return DM_MAPIO_REMAPPED;
         }
 
-        offset = dm_target_offset(ti, bio->bi_sector);
-        chunk = offset >> sc->chunk_shift;
-        stripe = sector_div(chunk, sc->stripes);
+        stripe_map_sector(sc, bio->bi_sector, &stripe, &bio->bi_sector);
 
+        bio->bi_sector += sc->stripe[stripe].physical_start;
         bio->bi_bdev = sc->stripe[stripe].dev->bdev;
-        bio->bi_sector = sc->stripe[stripe].physical_start +
-            (chunk << sc->chunk_shift) + (offset & sc->chunk_mask);
+
         return DM_MAPIO_REMAPPED;
 }