dm: move target request nr to dm_target_io
This patch moves target_request_nr from map_info to dm_target_io and
makes it accessible with dm_bio_get_target_request_nr.
This patch is a preparation for the next patch that removes map_info.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 5e88bc4..b7e179c 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1682,7 +1682,7 @@
chunk_t chunk;
if (bio->bi_rw & REQ_FLUSH) {
- if (!map_context->target_request_nr)
+ if (!dm_bio_get_target_request_nr(bio))
bio->bi_bdev = s->origin->bdev;
else
bio->bi_bdev = s->cow->bdev;
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index e2f87653..4e7ba82 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -279,13 +279,13 @@
unsigned target_request_nr;
if (bio->bi_rw & REQ_FLUSH) {
- target_request_nr = map_context->target_request_nr;
+ target_request_nr = dm_bio_get_target_request_nr(bio);
BUG_ON(target_request_nr >= sc->stripes);
bio->bi_bdev = sc->stripe[target_request_nr].dev->bdev;
return DM_MAPIO_REMAPPED;
}
if (unlikely(bio->bi_rw & REQ_DISCARD)) {
- target_request_nr = map_context->target_request_nr;
+ 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);
}
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 2765cf2..5ee580b 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1099,6 +1099,7 @@
tio->io = ci->io;
tio->ti = ti;
memset(&tio->info, 0, sizeof(tio->info));
+ tio->target_request_nr = 0;
return tio;
}
@@ -1109,7 +1110,7 @@
struct dm_target_io *tio = alloc_tio(ci, ti, ci->bio->bi_max_vecs);
struct bio *clone = &tio->clone;
- tio->info.target_request_nr = request_nr;
+ tio->target_request_nr = request_nr;
/*
* Discard requests require the bio's inline iovecs be initialized.
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 6f0e73b..eb96ef6 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -23,7 +23,6 @@
union map_info {
void *ptr;
unsigned long long ll;
- unsigned target_request_nr;
};
/*
@@ -193,20 +192,21 @@
* A number of zero-length barrier requests that will be submitted
* to the target for the purpose of flushing cache.
*
- * The request number will be placed in union map_info->target_request_nr.
+ * The request number can be accessed with dm_bio_get_target_request_nr.
* It is a responsibility of the target driver to remap these requests
* to the real underlying devices.
*/
unsigned num_flush_requests;
/*
- * The number of discard requests that will be submitted to the
- * target. map_info->request_nr is used just like num_flush_requests.
+ * The number of discard requests that will be submitted to the target.
+ * The request number can be accessed with dm_bio_get_target_request_nr.
*/
unsigned num_discard_requests;
/*
* The number of WRITE SAME requests that will be submitted to the target.
+ * The request number can be accessed with dm_bio_get_target_request_nr.
*/
unsigned num_write_same_requests;
@@ -263,6 +263,7 @@
struct dm_io *io;
struct dm_target *ti;
union map_info info;
+ unsigned target_request_nr;
struct bio clone;
};
@@ -276,6 +277,11 @@
return (struct bio *)((char *)data + data_size + offsetof(struct dm_target_io, clone));
}
+static inline unsigned dm_bio_get_target_request_nr(const struct bio *bio)
+{
+ return container_of(bio, struct dm_target_io, clone)->target_request_nr;
+}
+
int dm_register_target(struct target_type *t);
void dm_unregister_target(struct target_type *t);