dma-helpers: dma_blk_io() cancel support

Attempting to cancel a dma_blk_io() request causes an abort(3):

  void bdrv_aio_cancel(BlockAIOCB *acb)
  {
      ...
      while (acb->refcnt > 1) {
          if (acb->aiocb_info->get_aio_context) {
              aio_poll(acb->aiocb_info->get_aio_context(acb), true);
          } else if (acb->bs) {
              aio_poll(bdrv_get_aio_context(acb->bs), true);
          } else {
              abort();
          }
      }
      ...
  }

This happens because DMAAIOCB->bs is NULL and
dma_aiocb_info.get_aio_context() is also NULL.

This patch trivially implements dma_aiocb_info.get_aio_context() by
fetching the DMAAIOCB->ctx field.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466451417-27988-1-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2016-06-20 20:36:57 +01:00
parent 17c42b1f6b
commit 5fa78b2a1c

View file

@ -185,10 +185,17 @@ static void dma_aio_cancel(BlockAIOCB *acb)
}
}
static AioContext *dma_get_aio_context(BlockAIOCB *acb)
{
DMAAIOCB *dbs = container_of(acb, DMAAIOCB, common);
return dbs->ctx;
}
static const AIOCBInfo dma_aiocb_info = {
.aiocb_size = sizeof(DMAAIOCB),
.cancel_async = dma_aio_cancel,
.get_aio_context = dma_get_aio_context,
};
BlockAIOCB *dma_blk_io(AioContext *ctx,