xen-blkfront: Introduce blkif_ring_get_request

The code to get a request is always the same. Therefore we can factorize
it in a single function.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@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 ef5ce43e307adac52629cddd099c874430a1e439..0b32c90ffc3ffcde734fecc6fe8cc6d9593b318b 100644 (file)
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -481,6 +481,23 @@ static int blkif_ioctl(struct block_device *bdev, fmode_t mode,
        return 0;
 }
 
+static unsigned long blkif_ring_get_request(struct blkfront_ring_info *rinfo,
+                                           struct request *req,
+                                           struct blkif_request **ring_req)
+{
+       unsigned long id;
+
+       *ring_req = RING_GET_REQUEST(&rinfo->ring, rinfo->ring.req_prod_pvt);
+       rinfo->ring.req_prod_pvt++;
+
+       id = get_id_from_freelist(rinfo);
+       rinfo->shadow[id].request = req;
+
+       (*ring_req)->u.rw.id = id;
+
+       return id;
+}
+
 static int blkif_queue_discard_req(struct request *req, struct blkfront_ring_info *rinfo)
 {
        struct blkfront_info *info = rinfo->dev_info;
@@ -488,9 +505,7 @@ static int blkif_queue_discard_req(struct request *req, struct blkfront_ring_inf
        unsigned long id;
 
        /* Fill out a communications ring structure. */
-       ring_req = RING_GET_REQUEST(&rinfo->ring, rinfo->ring.req_prod_pvt);
-       id = get_id_from_freelist(rinfo);
-       rinfo->shadow[id].request = req;
+       id = blkif_ring_get_request(rinfo, req, &ring_req);
 
        ring_req->operation = BLKIF_OP_DISCARD;
        ring_req->u.discard.nr_sectors = blk_rq_sectors(req);
@@ -501,8 +516,6 @@ static int blkif_queue_discard_req(struct request *req, struct blkfront_ring_inf
        else
                ring_req->u.discard.flag = 0;
 
-       rinfo->ring.req_prod_pvt++;
-
        /* Keep a private copy so we can reissue requests when recovering. */
        rinfo->shadow[id].req = *ring_req;
 
@@ -635,9 +648,7 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
                }
 
        /* Fill out a communications ring structure. */
-       ring_req = RING_GET_REQUEST(&rinfo->ring, rinfo->ring.req_prod_pvt);
-       id = get_id_from_freelist(rinfo);
-       rinfo->shadow[id].request = req;
+       id = blkif_ring_get_request(rinfo, req, &ring_req);
 
        BUG_ON(info->max_indirect_segments == 0 &&
               GREFS(req->nr_phys_segments) > BLKIF_MAX_SEGMENTS_PER_REQUEST);
@@ -650,7 +661,6 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
        for_each_sg(rinfo->shadow[id].sg, sg, num_sg, i)
               num_grant += gnttab_count_grant(sg->offset, sg->length);
 
-       ring_req->u.rw.id = id;
        rinfo->shadow[id].num_sg = num_sg;
        if (num_grant > BLKIF_MAX_SEGMENTS_PER_REQUEST) {
                /*
@@ -716,8 +726,6 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
        if (setup.segments)
                kunmap_atomic(setup.segments);
 
-       rinfo->ring.req_prod_pvt++;
-
        /* Keep a private copy so we can reissue requests when recovering. */
        rinfo->shadow[id].req = *ring_req;