xen: Union the blkif_request request specific fields
Prepare for extending the block device ring to allow request
specific fields, by moving the request specific fields for
reads, writes and barrier requests to a union member.
Acked-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Owen Smith <owen.smith@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index d7aa39e..cc4514c 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -281,7 +281,7 @@
info->shadow[id].request = req;
ring_req->id = id;
- ring_req->sector_number = (blkif_sector_t)blk_rq_pos(req);
+ ring_req->u.rw.sector_number = (blkif_sector_t)blk_rq_pos(req);
ring_req->handle = info->handle;
ring_req->operation = rq_data_dir(req) ?
@@ -317,7 +317,7 @@
rq_data_dir(req) );
info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
- ring_req->seg[i] =
+ ring_req->u.rw.seg[i] =
(struct blkif_request_segment) {
.gref = ref,
.first_sect = fsect,
@@ -615,7 +615,7 @@
{
int i;
for (i = 0; i < s->req.nr_segments; i++)
- gnttab_end_foreign_access(s->req.seg[i].gref, 0, 0UL);
+ gnttab_end_foreign_access(s->req.u.rw.seg[i].gref, 0, 0UL);
}
static irqreturn_t blkif_interrupt(int irq, void *dev_id)
@@ -932,7 +932,7 @@
/* Rewrite any grant references invalidated by susp/resume. */
for (j = 0; j < req->nr_segments; j++)
gnttab_grant_foreign_access_ref(
- req->seg[j].gref,
+ req->u.rw.seg[j].gref,
info->xbdev->otherend_id,
pfn_to_mfn(info->shadow[req->id].frame[j]),
rq_data_dir(info->shadow[req->id].request));
diff --git a/include/xen/interface/io/blkif.h b/include/xen/interface/io/blkif.h
index c2d1fa4..e4f743c 100644
--- a/include/xen/interface/io/blkif.h
+++ b/include/xen/interface/io/blkif.h
@@ -51,11 +51,7 @@
*/
#define BLKIF_MAX_SEGMENTS_PER_REQUEST 11
-struct blkif_request {
- uint8_t operation; /* BLKIF_OP_??? */
- uint8_t nr_segments; /* number of segments */
- blkif_vdev_t handle; /* only for read/write requests */
- uint64_t id; /* private guest value, echoed in resp */
+struct blkif_request_rw {
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
struct blkif_request_segment {
grant_ref_t gref; /* reference to I/O buffer frame */
@@ -65,6 +61,16 @@
} seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
+struct blkif_request {
+ uint8_t operation; /* BLKIF_OP_??? */
+ uint8_t nr_segments; /* number of segments */
+ blkif_vdev_t handle; /* only for read/write requests */
+ uint64_t id; /* private guest value, echoed in resp */
+ union {
+ struct blkif_request_rw rw;
+ } u;
+};
+
struct blkif_response {
uint64_t id; /* copied from request */
uint8_t operation; /* copied from request */
