There's an ugly little memory leak in firewire-ohci's ar_context_tasklet(), where
we're not freeing up some of the memory we use for each ar_buffer, due to a
moving pointer. The problem has been there for a while, but didn't get noticed
until after converting the AR routines over to use coherent DMA and I started
running into I/O stall-outs with the following message output repeatedly to the
console:
PCI-DMA: Out of IOMMU space for 53248 bytes at device 0000:04:09.0
Plugging this leak is definitely necessary, but unfortunately, isn't the entire
answer to my problem, it only increases the amount of I/O that I can do before
hitting the problem. Still working on tracking down the root cause..
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
---
drivers/firewire/fw-ohci.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
index 8ff9059..e1d50f7 100644
--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -579,7 +579,8 @@ static void ar_context_tasklet(unsigned long data)
if (d->res_count == 0) {
size_t size, rest, offset;
- dma_addr_t buffer_bus;
+ dma_addr_t start_bus;
+ void *start;
/*
* This descriptor is finished and we may have a
@@ -588,9 +589,9 @@ static void ar_context_tasklet(unsigned long data)
*/
offset = offsetof(struct ar_buffer, data);
- buffer_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
+ start = buffer = ab;
+ start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
- buffer = ab;
ab = ab->next;
d = &ab->descriptor;
size = buffer + PAGE_SIZE - ctx->pointer;
@@ -605,7 +606,7 @@ static void ar_context_tasklet(unsigned long data)
buffer = handle_ar_packet(ctx, buffer);
dma_free_coherent(ohci->card.device, PAGE_SIZE,
- buffer, buffer_bus);
+ start, start_bus);
ar_context_add_page(ctx);
} else {
buffer = ctx->pointer;
--
Jarod Wilson
jwilson@redhat.com
--
