firewire: fw-ohci: fix IOMMU resource exhaustion

There is a DMA map/ unmap imbalance whenever a block write request
packet is sent and then dequeued with ohci_cancel_packet.  The latter
may happen frequently if the AR resp tasklet is executed before the AT
req tasklet for the same transaction.

Add the missing dma_unmap_single.  This fixes
https://bugzilla.redhat.com/show_bug.cgi?id=475156

Reported-by: Emmanuel Kowalski
Tested-by: Emmanuel Kowalski
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h
index aed7dbb17cda..839466f0a795 100644
--- a/drivers/firewire/fw-transaction.h
+++ b/drivers/firewire/fw-transaction.h
@@ -27,6 +27,7 @@
 #include <linux/list.h>
 #include <linux/spinlock_types.h>
 #include <linux/timer.h>
+#include <linux/types.h>
 #include <linux/workqueue.h>
 
 #define TCODE_IS_READ_REQUEST(tcode)    (((tcode) & ~1) == 4)
@@ -153,6 +154,7 @@ struct fw_packet {
         size_t header_length;
         void *payload;
         size_t payload_length;
+        dma_addr_t payload_bus;
         u32 timestamp;
 
         /*