--- drivers/firewire/ohci.c
+++ drivers/firewire/ohci.c
@@ -628,7 +628,7 @@ static void ar_context_tasklet(unsigned
d = &ab->descriptor;
if (d->res_count == 0) {
- size_t size, rest, offset;
+ size_t size, size2, rest, pktsize, size3, offset;
dma_addr_t start_bus;
void *start;
@@ -639,25 +639,61 @@ static void ar_context_tasklet(unsigned
*/
offset = offsetof(struct ar_buffer, data);
- start = buffer = ab;
+ start = ab;
start_bus = le32_to_cpu(ab->descriptor.data_address) - offset;
+ buffer = ab->data;
ab = ab->next;
d = &ab->descriptor;
- size = buffer + PAGE_SIZE - ctx->pointer;
+ size = start + PAGE_SIZE - ctx->pointer;
+ /* valid buffer data in the next page */
rest = le16_to_cpu(d->req_count) - le16_to_cpu(d->res_count);
+ /* what actually fits in this page */
+ size2 = min(rest, (size_t)PAGE_SIZE - offset - size);
memmove(buffer, ctx->pointer, size);
- memcpy(buffer + size, ab->data, rest);
- ctx->current_buffer = ab;
- ctx->pointer = (void *) ab->data + rest;
- end = buffer + size + rest;
-
- while (buffer < end)
- buffer = handle_ar_packet(ctx, buffer);
-
- dma_free_coherent(ohci->card.device, PAGE_SIZE,
- start, start_bus);
- ar_context_add_page(ctx);
+ memcpy(buffer + size, ab->data, size2);
+
+ while (size > 0) {
+ void *next = handle_ar_packet(ctx, buffer);
+ pktsize = next - buffer;
+ if (pktsize >= size) {
+ /*
+ * We have handled all the data that was
+ * originally in this page, so we can now
+ * continue in the next page.
+ */
+ buffer = next;
+ break;
+ }
+ /* move the next packet to the start of the buffer */
+ memmove(buffer, next, size + size2 - pktsize);
+ size -= pktsize;
+ /* fill up this page again */
+ size3 = min(rest - size2,
+ (size_t)PAGE_SIZE - offset - size - size2);
+ memcpy(buffer + size + size2,
+ (void *) ab->data + size2, size3);
+ size2 += size3;
+ }
+
+ if (rest > 0) {
+ /* handle the packets that are fully in the next page */
+ buffer = (void *) ab->data +
+ (buffer - (start + offset + size));
+ end = (void *) ab->data + rest;
+
+ while (buffer < end)
+ buffer = handle_ar_packet(ctx, buffer);
+
+ ctx->current_buffer = ab;
+ ctx->pointer = end;
+
+ dma_free_coherent(ohci->card.device, PAGE_SIZE,
+ start, start_bus);
+ ar_context_add_page(ctx);
+ } else {
+ ctx->pointer = start + PAGE_SIZE;
+ }
} else {
buffer = ctx->pointer;
ctx->pointer = end =
projects / ziggy471-frankenstein-kernel.git / blobdiff