firewire: fw-ohci: don't leak dma memory on module removal

The transmit and receive context dma memory was not being freed on
module removal.  Neither was the config rom memory.  Fix that.

The ab->next assignment is pure paranoia.

Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
index 251416f..5a5685f 100644
--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -476,6 +476,7 @@
 	if (ab == NULL)
 		return -ENOMEM;
 
+	ab->next = NULL;
 	memset(&ab->descriptor, 0, sizeof(ab->descriptor));
 	ab->descriptor.control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
 						    DESCRIPTOR_STATUS |
@@ -496,6 +497,21 @@
 	return 0;
 }
 
+static void ar_context_release(struct ar_context *ctx)
+{
+	struct ar_buffer *ab, *ab_next;
+	size_t offset;
+	dma_addr_t ab_bus;
+
+	for (ab = ctx->current_buffer; ab; ab = ab_next) {
+		ab_next = ab->next;
+		offset = offsetof(struct ar_buffer, data);
+		ab_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
+		dma_free_coherent(ctx->ohci->card.device, PAGE_SIZE,
+				  ab, ab_bus);
+	}
+}
+
 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
 #define cond_le32_to_cpu(v) \
 	(ohci->old_uninorth ? (__force __u32)(v) : le32_to_cpu(v))
@@ -2491,8 +2507,19 @@
 
 	software_reset(ohci);
 	free_irq(dev->irq, ohci);
+
+	if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
+		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
+				  ohci->next_config_rom, ohci->next_config_rom_bus);
+	if (ohci->config_rom)
+		dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
+				  ohci->config_rom, ohci->config_rom_bus);
 	dma_free_coherent(ohci->card.device, SELF_ID_BUF_SIZE,
 			  ohci->self_id_cpu, ohci->self_id_bus);
+	ar_context_release(&ohci->ar_request_ctx);
+	ar_context_release(&ohci->ar_response_ctx);
+	context_release(&ohci->at_request_ctx);
+	context_release(&ohci->at_response_ctx);
 	kfree(ohci->it_context_list);
 	kfree(ohci->ir_context_list);
 	pci_iounmap(dev, ohci->registers);