[Qemu-devel] [PATCH 2/4] hw/virtio-blk: add a constant for max number of merged requests

[Peter Lieven]

As it was not obvious (at least for me) where the 32 comes from;
add a constant for it.

Signed-off-by: Peter Lieven <p...@kamp.de>
Reviewed-by: Eric Blake <ebl...@redhat.com>
---
 hw/block/virtio-blk.c          |    2 +-
 include/hw/virtio/virtio-blk.h |    4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index b19b102..490f961 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -326,7 +326,7 @@ static void virtio_blk_handle_write(VirtIOBlockReq *req, 
MultiReqBuffer *mrb)
     block_acct_start(blk_get_stats(req->dev->blk), &req->acct, req->qiov.size,
                      BLOCK_ACCT_WRITE);
 
-    if (mrb->num_writes == 32) {
+    if (mrb->num_writes == VIRTIO_BLK_MAX_MERGE_REQS) {
         virtio_submit_multiwrite(req->dev->blk, mrb);
     }
 
diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h
index 3979dc4..3f2652f 100644
--- a/include/hw/virtio/virtio-blk.h
+++ b/include/hw/virtio/virtio-blk.h
@@ -134,8 +134,10 @@ typedef struct VirtIOBlock {
     struct VirtIOBlockDataPlane *dataplane;
 } VirtIOBlock;
 
+#define VIRTIO_BLK_MAX_MERGE_REQS 32
+
 typedef struct MultiReqBuffer {
-    BlockRequest        blkreq[32];
+    BlockRequest        blkreq[VIRTIO_BLK_MAX_MERGE_REQS];
     unsigned int        num_writes;
 } MultiReqBuffer;
 
-- 
1.7.9.5