From 6e40b3bfc7e82823cf4df5f0bf668f56db41e53a Mon Sep 17 00:00:00 2001
From: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Date: Wed, 17 Jun 2015 13:37:20 +0300
Subject: [PATCH] virtio-blk: Use blk_drain() to drain IO requests
Each call of the virtio_blk_reset() function calls blk_drain_all(),
which works for all existing BlockDriverStates, while draining only
one is needed.
This patch replaces blk_drain_all() by blk_drain() in
virtio_blk_reset(). virtio_blk_data_plane_stop() should be called
after draining because it restores vblk->complete_request.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Message-id: 1434537440-28236-3-git-send-email-yarygin@linux.vnet.ibm.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
hw/block/virtio-blk.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index cd539aa11c..bbb1fc1877 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -651,16 +651,21 @@ static void virtio_blk_dma_restart_cb(void *opaque, int running,
static void virtio_blk_reset(VirtIODevice *vdev)
{
VirtIOBlock *s = VIRTIO_BLK(vdev);
-
- if (s->dataplane) {
- virtio_blk_data_plane_stop(s->dataplane);
- }
+ AioContext *ctx;
/*
* This should cancel pending requests, but can't do nicely until there
* are per-device request lists.
*/
- blk_drain_all();
+ ctx = blk_get_aio_context(s->blk);
+ aio_context_acquire(ctx);
+ blk_drain(s->blk);
+
+ if (s->dataplane) {
+ virtio_blk_data_plane_stop(s->dataplane);
+ }
+ aio_context_release(ctx);
+
blk_set_enable_write_cache(s->blk, s->original_wce);
}
--
2.30.2