diff options
| -rw-r--r-- | hw/scsi/esp.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c index ec9fcbe..1c7bad8 100644 --- a/hw/scsi/esp.c +++ b/hw/scsi/esp.c @@ -631,7 +631,9 @@ static void esp_do_dma(ESPState *s) switch (s->rregs[ESP_CMD]) { case CMD_TI | CMD_DMA: if (s->dma_memory_write) { - s->dma_memory_write(s->dma_opaque, s->async_buf, len); + if (len) { + s->dma_memory_write(s->dma_opaque, s->async_buf, len); + } } else { /* Copy device data to FIFO */ len = MIN(len, fifo8_num_free(&s->fifo)); @@ -681,6 +683,7 @@ static void esp_do_dma(ESPState *s) buf[0] = s->status; if (s->dma_memory_write) { + /* Length already non-zero */ s->dma_memory_write(s->dma_opaque, buf, len); } else { esp_fifo_push_buf(s, buf, len); @@ -715,6 +718,7 @@ static void esp_do_dma(ESPState *s) buf[0] = 0; if (s->dma_memory_write) { + /* Length already non-zero */ s->dma_memory_write(s->dma_opaque, buf, len); } else { esp_fifo_push_buf(s, buf, len); |