diff options
Diffstat (limited to 'hw/ide/pci.c')
| -rw-r--r-- | hw/ide/pci.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/hw/ide/pci.c b/hw/ide/pci.c index 4331d77232..ec90f266e9 100644 --- a/hw/ide/pci.c +++ b/hw/ide/pci.c @@ -40,8 +40,27 @@ void bmdma_cmd_writeb(void *opaque, uint32_t addr, uint32_t val) printf("%s: 0x%08x\n", __func__, val); #endif if (!(val & BM_CMD_START)) { - /* XXX: do it better */ - ide_dma_cancel(bm); + /* + * We can't cancel Scatter Gather DMA in the middle of the + * operation or a partial (not full) DMA transfer would reach + * the storage so we wait for completion instead (we beahve + * like if the DMA was completed by the time the guest trying + * to cancel dma with bmdma_cmd_writeb with BM_CMD_START not + * set). + * + * In the future we'll be able to safely cancel the I/O if the + * whole DMA operation will be submitted to disk with a single + * aio operation with preadv/pwritev. + */ + if (bm->aiocb) { + qemu_aio_flush(); +#ifdef DEBUG_IDE + if (bm->aiocb) + printf("ide_dma_cancel: aiocb still pending"); + if (bm->status & BM_STATUS_DMAING) + printf("ide_dma_cancel: BM_STATUS_DMAING still pending"); +#endif + } bm->cmd = val & 0x09; } else { if (!(bm->status & BM_STATUS_DMAING)) { |