diff mbox

[for-2.5,3/4] block: replace IOV_MAX with BlockLimits.max_iov

Message ID 1436369462-24252-4-git-send-email-stefanha@redhat.com
State New
Headers show

Commit Message

Stefan Hajnoczi July 8, 2015, 3:31 p.m. UTC 
Request merging must not result in a huge request that exceeds the
maximum number of iovec elements.  Use BlockLimits.max_iov instead of
hardcoding IOV_MAX.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/io.c            | 3 ++-
 hw/block/virtio-blk.c | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/block/io.c b/block/io.c
index 6750de6..baffd02 100644
--- a/block/io.c
+++ b/block/io.c
@@ -1818,7 +1818,8 @@  static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
             merge = 1;
         }
 
-        if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) {
+        if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 >
+            bs->bl.max_iov) {
             merge = 0;
         }
 
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index 6aefda4..a186956 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -407,7 +407,7 @@  void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb)
             bool merge = true;
 
             /* merge would exceed maximum number of IOVs */
-            if (niov + req->qiov.niov > IOV_MAX) {
+            if (niov + req->qiov.niov > blk_get_max_iov(blk)) {
                 merge = false;
             }