[patch 16/22] firewire: fw-ohci: fix IOMMU resource exhaustion

Greg KH
2008-12-17T00:09:50Z

[-- Attachment #1: firewire-fw-ohci-fix-iommu-resource-exhaustion.patch --]
[-- Type: text/plain, Size: 3169 bytes --]

2.6.27-stable review patch. If anyone has any objections, please let us know.

------------------

From: Stefan Richter <stefanr@s5r6.in-berlin.de>

commit 1d1dc5e83f3299c108a4e44d58cc4bfef48c876a upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/firewire/fw-ohci.c | 11 +++++++----
drivers/firewire/fw-transaction.c | 3 +++
drivers/firewire/fw-transaction.h | 2 ++
3 files changed, 12 insertions(+), 4 deletions(-)

--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -958,6 +958,7 @@ at_context_queue_packet(struct context *
packet->ack = RCODE_SEND_ERROR;
return -1;
}
+ packet->payload_bus = payload_bus;

d[2].req_count = cpu_to_le16(packet->payload_length);
d[2].data_address = cpu_to_le32(payload_bus);
@@ -1009,7 +1010,6 @@ static int handle_at_packet(struct conte
struct driver_data *driver_data;
struct fw_packet *packet;
struct fw_ohci *ohci = context->ohci;
- dma_addr_t payload_bus;
int evt;

if (last->transfer_status == 0)
@@ -1022,9 +1022,8 @@ static int handle_at_packet(struct conte
/* This packet was cancelled, just continue. */
return 1;

- payload_bus = le32_to_cpu(last->data_address);
- if (payload_bus != 0)
- dma_unmap_single(ohci->card.device, payload_bus,
+ if (packet->payload_bus)
+ dma_unmap_single(ohci->card.device, packet->payload_bus,
packet->payload_length, DMA_TO_DEVICE);

evt = le16_to_cpu(last->transfer_status) & 0x1f;
@@ -1681,6 +1680,10 @@ static int ohci_cancel_packet(struct fw_
if (packet->ack != 0)
goto out;

+ if (packet->payload_bus)
+ dma_unmap_single(ohci->card.device, packet->payload_bus,
+ packet->payload_length, DMA_TO_DEVICE);
+
log_ar_at_event('T', packet->speed, packet->header, 0x20);
driver_data->packet = NULL;
packet->ack = RCODE_CANCELLED;
--- a/drivers/firewire/fw-transaction.c
+++ b/drivers/firewire/fw-transaction.c
@@ -207,6 +207,7 @@ fw_fill_request(struct fw_packet *packet
packet->speed = speed;
packet->generation = generation;
packet->ack = 0;
+ packet->payload_bus = 0;
}

/**
@@ -541,6 +542,8 @@ fw_fill_response(struct fw_packet *respo
BUG();
return;
}
+
+ response->payload_bus = 0;
}
EXPORT_SYMBOL(fw_fill_response);

--- 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;

/*