xen/blk[front|back]: Squash blkif_request_rw and blkif_request_discard together
In a union type structure to deal with the overlapping
attributes in a easier manner.
Suggested-by: Ian Campbell <Ian.Campbell@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 7b2ec59..2c2c4be 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -135,15 +135,15 @@
{
unsigned long free = info->shadow_free;
BUG_ON(free >= BLK_RING_SIZE);
- info->shadow_free = info->shadow[free].req.id;
- info->shadow[free].req.id = 0x0fffffee; /* debug */
+ info->shadow_free = info->shadow[free].req.u.rw.id;
+ info->shadow[free].req.u.rw.id = 0x0fffffee; /* debug */
return free;
}
static void add_id_to_freelist(struct blkfront_info *info,
unsigned long id)
{
- info->shadow[id].req.id = info->shadow_free;
+ info->shadow[id].req.u.rw.id = info->shadow_free;
info->shadow[id].request = NULL;
info->shadow_free = id;
}
@@ -287,9 +287,9 @@
id = get_id_from_freelist(info);
info->shadow[id].request = req;
- ring_req->id = id;
+ ring_req->u.rw.id = id;
ring_req->u.rw.sector_number = (blkif_sector_t)blk_rq_pos(req);
- ring_req->handle = info->handle;
+ ring_req->u.rw.handle = info->handle;
ring_req->operation = rq_data_dir(req) ?
BLKIF_OP_WRITE : BLKIF_OP_READ;
@@ -308,13 +308,15 @@
if (unlikely(req->cmd_flags & REQ_DISCARD)) {
/* id, sector_number and handle are set above. */
ring_req->operation = BLKIF_OP_DISCARD;
- ring_req->nr_segments = 0;
+ ring_req->u.discard.nr_segments = 0;
ring_req->u.discard.nr_sectors = blk_rq_sectors(req);
} else {
- ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
- BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
+ ring_req->u.rw.nr_segments = blk_rq_map_sg(req->q, req,
+ info->sg);
+ BUG_ON(ring_req->u.rw.nr_segments >
+ BLKIF_MAX_SEGMENTS_PER_REQUEST);
- for_each_sg(info->sg, sg, ring_req->nr_segments, i) {
+ for_each_sg(info->sg, sg, ring_req->u.rw.nr_segments, i) {
buffer_mfn = pfn_to_mfn(page_to_pfn(sg_page(sg)));
fsect = sg->offset >> 9;
lsect = fsect + (sg->length >> 9) - 1;
@@ -705,7 +707,7 @@
static void blkif_completion(struct blk_shadow *s)
{
int i;
- for (i = 0; i < s->req.nr_segments; i++)
+ for (i = 0; i < s->req.u.rw.nr_segments; i++)
gnttab_end_foreign_access(s->req.u.rw.seg[i].gref, 0, 0UL);
}
@@ -763,7 +765,7 @@
error = -EOPNOTSUPP;
}
if (unlikely(bret->status == BLKIF_RSP_ERROR &&
- info->shadow[id].req.nr_segments == 0)) {
+ info->shadow[id].req.u.rw.nr_segments == 0)) {
printk(KERN_WARNING "blkfront: %s: empty write %s op failed\n",
info->flush_op == BLKIF_OP_WRITE_BARRIER ?
"barrier" : "flush disk cache",
@@ -984,8 +986,8 @@
INIT_WORK(&info->work, blkif_restart_queue);
for (i = 0; i < BLK_RING_SIZE; i++)
- info->shadow[i].req.id = i+1;
- info->shadow[BLK_RING_SIZE-1].req.id = 0x0fffffff;
+ info->shadow[i].req.u.rw.id = i+1;
+ info->shadow[BLK_RING_SIZE-1].req.u.rw.id = 0x0fffffff;
/* Front end dir is a number, which is used as the id. */
info->handle = simple_strtoul(strrchr(dev->nodename, '/')+1, NULL, 0);
@@ -1019,9 +1021,9 @@
/* Stage 2: Set up free list. */
memset(&info->shadow, 0, sizeof(info->shadow));
for (i = 0; i < BLK_RING_SIZE; i++)
- info->shadow[i].req.id = i+1;
+ info->shadow[i].req.u.rw.id = i+1;
info->shadow_free = info->ring.req_prod_pvt;
- info->shadow[BLK_RING_SIZE-1].req.id = 0x0fffffff;
+ info->shadow[BLK_RING_SIZE-1].req.u.rw.id = 0x0fffffff;
/* Stage 3: Find pending requests and requeue them. */
for (i = 0; i < BLK_RING_SIZE; i++) {
@@ -1034,17 +1036,17 @@
*req = copy[i].req;
/* We get a new request id, and must reset the shadow state. */
- req->id = get_id_from_freelist(info);
- memcpy(&info->shadow[req->id], ©[i], sizeof(copy[i]));
+ req->u.rw.id = get_id_from_freelist(info);
+ memcpy(&info->shadow[req->u.rw.id], ©[i], sizeof(copy[i]));
/* Rewrite any grant references invalidated by susp/resume. */
- for (j = 0; j < req->nr_segments; j++)
+ for (j = 0; j < req->u.rw.nr_segments; j++)
gnttab_grant_foreign_access_ref(
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));
- info->shadow[req->id].req = *req;
+ pfn_to_mfn(info->shadow[req->u.rw.id].frame[j]),
+ rq_data_dir(info->shadow[req->u.rw.id].request));
+ info->shadow[req->u.rw.id].req = *req;
info->ring.req_prod_pvt++;
}