We can cancel I/O requests safely if they are not sent to the servers.
Signed-off-by: MORITA Kazutaka <morita.kazut...@lab.ntt.co.jp>
---
block/sheepdog.c | 37 +++++++++++++++++++++++++++++++++++++
1 files changed, 37 insertions(+), 0 deletions(-)
diff --git a/block/sheepdog.c b/block/sheepdog.c
index cedf806..ed98701 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -421,6 +421,43 @@ static void sd_finish_aiocb(SheepdogAIOCB *acb)
static void sd_aio_cancel(BlockDriverAIOCB *blockacb)
{
SheepdogAIOCB *acb = (SheepdogAIOCB *)blockacb;
+ BDRVSheepdogState *s = blockacb->bs->opaque;
+ AIOReq *areq, *next, *oldest_send_req = NULL;
+
+ if (acb->bh) {
+ /*
+ * sd_readv_writev_bh_cb() is not called yet, so we can
+ * release this safely
+ */
+ qemu_bh_delete(acb->bh);
+ acb->bh = NULL;
+ qemu_aio_release(acb);
+ return;
+ }
+
+ QLIST_FOREACH(areq, &s->outstanding_aio_head, outstanding_aio_siblings) {
+ if (areq->state == AIO_SEND_OBJREQ) {
+ oldest_send_req = areq;
+ }
+ }
+
+ QLIST_FOREACH_SAFE(areq, &s->outstanding_aio_head,
+ outstanding_aio_siblings, next) {
+ if (areq->state == AIO_RECV_OBJREQ) {
+ continue;
+ }
+ if (areq->state == AIO_SEND_OBJREQ && areq == oldest_send_req) {
+ /* the oldest AIO_SEND_OBJREQ request could be being sent */
+ continue;
+ }
+ free_aio_req(s, areq);
+ }
+
+ if (QLIST_EMPTY(&acb->aioreq_head)) {
+ /* there is no outstanding request */
+ qemu_aio_release(acb);
+ return;
+ }
/*
* Sheepdog cannot cancel the requests which are already sent to
--
1.5.6.5
