usb: dwc2: Fix inefficient copy of unaligned buffers

Make sure only to copy any actual data rather than the whole buffer,
when releasing the temporary buffer used for unaligned non-isochronous
transfers.

Taken directly from commit 0efd937e27 ("USB: ehci-tegra: fix inefficient
copy of unaligned buffers")

Tested with Lantiq xRX200 (MIPS) and RPi Model B Rev 2 (ARM)

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Antti Seppälä <a.seppala@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
This commit is contained in:
Antti Seppälä 2018-07-05 17:31:54 +03:00 committed by Felipe Balbi
parent 56406e017a
commit 1e111e8852

View file

@ -2668,6 +2668,7 @@ static int dwc2_alloc_split_dma_aligned_buf(struct dwc2_hsotg *hsotg,
static void dwc2_free_dma_aligned_buffer(struct urb *urb)
{
void *stored_xfer_buffer;
size_t length;
if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
return;
@ -2676,9 +2677,14 @@ static void dwc2_free_dma_aligned_buffer(struct urb *urb)
memcpy(&stored_xfer_buffer, urb->transfer_buffer +
urb->transfer_buffer_length, sizeof(urb->transfer_buffer));
if (usb_urb_dir_in(urb))
memcpy(stored_xfer_buffer, urb->transfer_buffer,
urb->transfer_buffer_length);
if (usb_urb_dir_in(urb)) {
if (usb_pipeisoc(urb->pipe))
length = urb->transfer_buffer_length;
else
length = urb->actual_length;
memcpy(stored_xfer_buffer, urb->transfer_buffer, length);
}
kfree(urb->transfer_buffer);
urb->transfer_buffer = stored_xfer_buffer;