[dm-devel] [PATCH 1/2 v2] dm stripe: move sector translation to a function
Mike Snitzer
snitzer at redhat.com
Wed Jul 28 17:09:10 UTC 2010
From: Mikulas Patocka <mpatocka at redhat.com>
Abstract sector -> stripe translation to a function.
Signed-off-by: Mikulas Patocka <mpatocka at redhat.com>
Signed-off-by: Mike Snitzer <snitzer at redhat.com>
---
drivers/md/dm-stripe.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
v2: fix conflict with newly staged dm_target_offset changes
Index: linux-2.6/drivers/md/dm-stripe.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-stripe.c
+++ linux-2.6/drivers/md/dm-stripe.c
@@ -207,11 +207,19 @@ static void stripe_dtr(struct dm_target
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;
uint32_t stripe;
unsigned target_request_nr;
@@ -222,13 +230,11 @@ static int stripe_map(struct dm_target *
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;
}
More information about the dm-devel
mailing list