USB: remove uses of URB_NO_SETUP_DMA_MAP
This patch (as1350) removes all usages of coherent buffers for USB
control-request setup-packet buffers. There's no good reason to
reserve coherent memory for these things; control requests are hardly
ever used in large quantity (the major exception is firmware
transfers, and they aren't time-critical). Furthermore, only seven
drivers used it. We might as well always use streaming DMA mappings
for setup-packet buffers, and remove some extra complexity from
usbcore.
The DMA-mapping portion of hcd.c is currently in flux. A separate
patch will be submitted to remove support for URB_NO_SETUP_DMA_MAP
after everything else settles down. The removal should go smoothly,
as by then nobody will be using it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index bbeeb92..c54a370 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -407,9 +407,8 @@
/* Store our private data in the interface */
usb_set_intfdata(intf, us);
- /* Allocate the device-related DMA-mapped buffers */
- us->cr = usb_buffer_alloc(us->pusb_dev, sizeof(*us->cr),
- GFP_KERNEL, &us->cr_dma);
+ /* Allocate the control/setup and DMA-mapped buffers */
+ us->cr = kmalloc(sizeof(*us->cr), GFP_KERNEL);
if (!us->cr) {
US_DEBUGP("usb_ctrlrequest allocation failed\n");
return -ENOMEM;
@@ -757,13 +756,9 @@
{
US_DEBUGP("-- %s\n", __func__);
- /* Free the device-related DMA-mapped buffers */
- if (us->cr)
- usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
- us->cr_dma);
- if (us->iobuf)
- usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf,
- us->iobuf_dma);
+ /* Free the buffers */
+ kfree(us->cr);
+ usb_buffer_free(us->pusb_dev, US_IOBUF_SIZE, us->iobuf, us->iobuf_dma);
/* Remove our private data from the interface */
usb_set_intfdata(us->pusb_intf, NULL);