firewire: fw-sbp2: fix DMA mapping of management 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, 9 insertions, 12 deletions

diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index f488ff8903fc..7c53be0387fb 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -416,21 +416,11 @@ sbp2_send_management_orb(struct fw_unit *unit, int node_id, int generation,
         if (orb == NULL)
                 return -ENOMEM;
 
-        /*
-         * The sbp2 device is going to send a block read request to
-         * read out the request from host memory, so map it for dma.
-         */
-        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 out;
-
         orb->response_bus =
                 dma_map_single(device->card->device, &orb->response,
                                sizeof(orb->response), DMA_FROM_DEVICE);
         if (dma_mapping_error(orb->response_bus))
-                goto out;
+                goto fail_mapping_response;
 
         orb->request.response.high    = 0;
         orb->request.response.low     = orb->response_bus;
@@ -456,6 +446,12 @@ sbp2_send_management_orb(struct fw_unit *unit, int node_id, int generation,
         init_completion(&orb->done);
         orb->base.callback = complete_management_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_request;
+
         sbp2_send_orb(&orb->base, unit,
                       node_id, generation, sd->management_agent_address);
 
@@ -487,9 +483,10 @@ sbp2_send_management_orb(struct fw_unit *unit, int node_id, int generation,
  out:
         dma_unmap_single(device->card->device, orb->base.request_bus,
                          sizeof(orb->request), DMA_TO_DEVICE);
+ fail_mapping_request:
         dma_unmap_single(device->card->device, orb->response_bus,
                          sizeof(orb->response), DMA_FROM_DEVICE);
-
+ fail_mapping_response:
         if (response)
                 fw_memcpy_from_be32(response,
                                     orb->response, sizeof(orb->response));