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/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);