firewire: fw-sbp2: fix DMA mapping of command ORBs

The CPU must not touch the buffer after it was DMA-mapped.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>

1 files changed, 6 insertions, 9 deletions

diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index a2ddf318a250..f488ff8903fc 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -1009,11 +1009,6 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
 
         /* Initialize rcode to something not RCODE_COMPLETE. */
         orb->base.rcode = -1;
-        orb->base.request_bus =
-                dma_map_single(device->card->device, &orb->request,
-                               sizeof(orb->request), DMA_TO_DEVICE);
-        if (dma_mapping_error(orb->base.request_bus))
-                goto fail_mapping;
 
         orb->unit = unit;
         orb->done = done;
@@ -1040,7 +1035,7 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_TO_MEDIA);
 
         if (cmd->use_sg && sbp2_command_orb_map_scatterlist(orb) < 0)
-                goto fail_map_payload;
+                goto fail_mapping;
 
         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
 
@@ -1049,15 +1044,17 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
         memcpy(orb->request.command_block, cmd->cmnd, COMMAND_SIZE(*cmd->cmnd));
 
         orb->base.callback = complete_command_orb;
+        orb->base.request_bus =
+                dma_map_single(device->card->device, &orb->request,
+                               sizeof(orb->request), DMA_TO_DEVICE);
+        if (dma_mapping_error(orb->base.request_bus))
+                goto fail_mapping;
 
         sbp2_send_orb(&orb->base, unit, sd->node_id, sd->generation,
                       sd->command_block_agent_address + SBP2_ORB_POINTER);
 
         return 0;
 
- fail_map_payload:
-        dma_unmap_single(device->card->device, orb->base.request_bus,
-                         sizeof(orb->request), DMA_TO_DEVICE);
  fail_mapping:
         kfree(orb);
  fail_alloc: