dm-crypt: use bi_sector in bio when initialize integrity seed

bio->bi_iter.bi_sector has already been initialized when initialize the
integrity seed in dm_crypt_integrity_io_alloc(). There is no need to
calculate it again. Therefore, use the helper bip_set_seed() to
initialize the seed and pass bi_iter.bi_sector to it instead.

Mikulas: We can't use bip_set_seed because it doesn't compile without
CONFIG_BLK_DEV_INTEGRITY.

Signed-off-by: Hou Tao <[email protected]>
Signed-off-by: Mikulas Patocka <[email protected]>

Author: Hou Tao

drivers/md/dm-crypt.c

@@ -1187,7 +1187,7 @@ static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
 
 	tag_len = io->cc->tuple_size * (bio_sectors(bio) >> io->cc->sector_shift);
 
-	bip->bip_iter.bi_sector = io->cc->start + io->sector;
+	bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
 
 	ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
 				     tag_len, offset_in_page(io->integrity_metadata));