Commit c29947bb authored by Kevin Wolf's avatar Kevin Wolf
Browse files

ide: Ignore double DMA transfer starts/stops 



You can only start a DMA transfer if it's not running yet, and you can only
cancel it if it's running.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
parent e3982b3c

hw/ide/pci.c

+32 −28
Original line number Diff line number Diff line
@@ -39,6 +39,9 @@ void bmdma_cmd_writeb(void *opaque, uint32_t addr, uint32_t val) 
#ifdef DEBUG_IDE

    printf("%s: 0x%08x\n", __func__, val);

#endif



    /* 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)) {

            /*

             * We can't cancel Scatter Gather DMA in the middle of the
@@ -61,7 +64,6 @@ void bmdma_cmd_writeb(void *opaque, uint32_t addr, uint32_t val) 
                    printf("ide_dma_cancel: BM_STATUS_DMAING still pending");

#endif

            }

        bm->cmd = val & 0x09;

        } else {

            if (!(bm->status & BM_STATUS_DMAING)) {

                bm->status |= BM_STATUS_DMAING;
@@ -69,10 +71,12 @@ void bmdma_cmd_writeb(void *opaque, uint32_t addr, uint32_t val) 
                if (bm->dma_cb)

                    bm->dma_cb(bm, 0);

            }

        bm->cmd = val & 0x09;

        }

    }



    bm->cmd = val & 0x09;

}



static void bmdma_addr_read(IORange *ioport, uint64_t addr,

                            unsigned width, uint64_t *data)

{