From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37204) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZuccZ-0000pk-PX for qemu-devel@nongnu.org; Fri, 06 Nov 2015 03:43:44 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZuccW-0002Zo-E5 for qemu-devel@nongnu.org; Fri, 06 Nov 2015 03:43:43 -0500 Received: from mx-v6.kamp.de ([2a02:248:0:51::16]:43883 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZuccW-0002Yj-50 for qemu-devel@nongnu.org; Fri, 06 Nov 2015 03:43:40 -0500 From: Peter Lieven Date: Fri, 6 Nov 2015 09:42:51 +0100 Message-Id: <1446799373-6144-5-git-send-email-pl@kamp.de> In-Reply-To: <1446799373-6144-1-git-send-email-pl@kamp.de> References: <1446799373-6144-1-git-send-email-pl@kamp.de> Subject: [Qemu-devel] [PATCH V3 4/6] ide: orphan all buffered requests on DMA cancel List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, qemu-block@nongnu.org Cc: kwolf@redhat.com, stefanha@gmail.com, jcody@redhat.com, jsnow@redhat.com, Peter Lieven If the guests canceles a DMA request we can prematurely invoke all callbacks of buffered requests and flag all them as orphaned. Ideally this avoids the need for draining all requests. For CDROM devices this works in 100% of all cases. Signed-off-by: Peter Lieven --- hw/ide/pci.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/hw/ide/pci.c b/hw/ide/pci.c index d31ff88..a9e164e 100644 --- a/hw/ide/pci.c +++ b/hw/ide/pci.c @@ -240,6 +240,22 @@ void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val) /* Ignore writes to SSBM if it keeps the old value */ if ((val & BM_CMD_START) != (bm->cmd & BM_CMD_START)) { if (!(val & BM_CMD_START)) { + /* First invoke the callbacks of all buffered requests + * and flag those requests as orphaned. Ideally there + * are no unbuffered (Scatter Gather DMA Requests or + * write requests) pending and we can avoid to drain. */ + IDEBufferedRequest *req; + IDEState *s = idebus_active_if(bm->bus); + QLIST_FOREACH(req, &s->buffered_requests, list) { + if (!req->orphaned) { +#ifdef DEBUG_IDE + printf("%s: invoking cb %p of buffered request %p with" + " -ECANCELED\n", __func__, req->original_cb, req); +#endif + req->original_cb(req->original_opaque, -ECANCELED); + } + req->orphaned = true; + } /* * We can't cancel Scatter Gather DMA in the middle of the * operation or a partial (not full) DMA transfer would reach @@ -253,6 +269,9 @@ void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val) * aio operation with preadv/pwritev. */ if (bm->bus->dma->aiocb) { +#ifdef DEBUG_IDE + printf("%s: draining all remaining requests", __func__); +#endif blk_drain_all(); assert(bm->bus->dma->aiocb == NULL); } -- 1.9.1