dm crypt: add merge

This patch implements biovec merge function for crypt target.

If the underlying device has merge function defined, call it.
If not, keep precomputed value.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Milan Broz 2008-07-21 12:00:40 +01:00 committed by Alasdair G Kergon
parent 9980c638a6
commit d41e26b901

View file

@ -1216,9 +1216,24 @@ static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
return -EINVAL;
}
static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
struct bio_vec *biovec, int max_size)
{
struct crypt_config *cc = ti->private;
struct request_queue *q = bdev_get_queue(cc->dev->bdev);
if (!q->merge_bvec_fn)
return max_size;
bvm->bi_bdev = cc->dev->bdev;
bvm->bi_sector = cc->start + bvm->bi_sector - ti->begin;
return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
}
static struct target_type crypt_target = {
.name = "crypt",
.version= {1, 5, 0},
.version= {1, 6, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,
@ -1228,6 +1243,7 @@ static struct target_type crypt_target = {
.preresume = crypt_preresume,
.resume = crypt_resume,
.message = crypt_message,
.merge = crypt_merge,
};
static int __init dm_crypt_init(void)