From 7cda62087c0baf064486f3d803184c2c3b35c04a Mon Sep 17 00:00:00 2001 From: Peter Lieven Date: Tue, 17 Nov 2015 15:06:29 -0500 Subject: ide: orphan all buffered requests on DMA cancel 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 Reviewed-by: Fam Zheng Message-id: 1447345846-15624-5-git-send-email-pl@kamp.de Signed-off-by: John Snow --- hw/ide/pci.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'hw') diff --git a/hw/ide/pci.c b/hw/ide/pci.c index 9c54b37..37dbc29 100644 --- a/hw/ide/pci.c +++ b/hw/ide/pci.c @@ -233,6 +233,22 @@ 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 @@ -246,6 +262,9 @@ 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); } -- cgit v1.1