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>

3 files changed, 6 insertions, 11 deletions

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 7b85b69..6a510c9 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -787,8 +787,7 @@ static int hid_alloc_buffers(struct usb_device *dev, struct hid_device *hid)
 			&usbhid->inbuf_dma);
 	usbhid->outbuf = usb_buffer_alloc(dev, usbhid->bufsize, GFP_KERNEL,
 			&usbhid->outbuf_dma);
-	usbhid->cr = usb_buffer_alloc(dev, sizeof(*usbhid->cr), GFP_KERNEL,
-			&usbhid->cr_dma);
+	usbhid->cr = kmalloc(sizeof(*usbhid->cr), GFP_KERNEL);
 	usbhid->ctrlbuf = usb_buffer_alloc(dev, usbhid->bufsize, GFP_KERNEL,
 			&usbhid->ctrlbuf_dma);
 	if (!usbhid->inbuf || !usbhid->outbuf || !usbhid->cr ||
@@ -846,7 +845,7 @@ static void hid_free_buffers(struct usb_device *dev, struct hid_device *hid)
 
 	usb_buffer_free(dev, usbhid->bufsize, usbhid->inbuf, usbhid->inbuf_dma);
 	usb_buffer_free(dev, usbhid->bufsize, usbhid->outbuf, usbhid->outbuf_dma);
-	usb_buffer_free(dev, sizeof(*(usbhid->cr)), usbhid->cr, usbhid->cr_dma);
+	kfree(usbhid->cr);
 	usb_buffer_free(dev, usbhid->bufsize, usbhid->ctrlbuf, usbhid->ctrlbuf_dma);
 }
 
@@ -1007,9 +1006,8 @@ static int usbhid_start(struct hid_device *hid)
 
 	usb_fill_control_urb(usbhid->urbctrl, dev, 0, (void *) usbhid->cr,
 			     usbhid->ctrlbuf, 1, hid_ctrl, hid);
-	usbhid->urbctrl->setup_dma = usbhid->cr_dma;
 	usbhid->urbctrl->transfer_dma = usbhid->ctrlbuf_dma;
-	usbhid->urbctrl->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP);
+	usbhid->urbctrl->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 
 	if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
 		usbhid_init_reports(hid);
diff --git a/drivers/hid/usbhid/usbhid.h b/drivers/hid/usbhid/usbhid.h
index ec20400..693fd3e 100644
--- a/drivers/hid/usbhid/usbhid.h
+++ b/drivers/hid/usbhid/usbhid.h
@@ -75,7 +75,6 @@ struct usbhid_device {
 
 	struct urb *urbctrl;                                            /* Control URB */
 	struct usb_ctrlrequest *cr;                                     /* Control request struct */
-	dma_addr_t cr_dma;                                              /* Control request struct dma */
 	struct hid_control_fifo ctrl[HID_CONTROL_FIFO_SIZE];  		/* Control fifo */
 	unsigned char ctrlhead, ctrltail;                               /* Control fifo head & tail */
 	char *ctrlbuf;                                                  /* Control buffer */
diff --git a/drivers/hid/usbhid/usbkbd.c b/drivers/hid/usbhid/usbkbd.c
index f843443..bdc7b09 100644
--- a/drivers/hid/usbhid/usbkbd.c
+++ b/drivers/hid/usbhid/usbkbd.c
@@ -74,7 +74,6 @@ struct usb_kbd {
 	unsigned char *new;
 	struct usb_ctrlrequest *cr;
 	unsigned char *leds;
-	dma_addr_t cr_dma;
 	dma_addr_t new_dma;
 	dma_addr_t leds_dma;
 };
@@ -199,7 +198,7 @@ static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
 		return -1;
 	if (!(kbd->new = usb_buffer_alloc(dev, 8, GFP_ATOMIC, &kbd->new_dma)))
 		return -1;
-	if (!(kbd->cr = usb_buffer_alloc(dev, sizeof(struct usb_ctrlrequest), GFP_ATOMIC, &kbd->cr_dma)))
+	if (!(kbd->cr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL)))
 		return -1;
 	if (!(kbd->leds = usb_buffer_alloc(dev, 1, GFP_ATOMIC, &kbd->leds_dma)))
 		return -1;
@@ -212,7 +211,7 @@ static void usb_kbd_free_mem(struct usb_device *dev, struct usb_kbd *kbd)
 	usb_free_urb(kbd->irq);
 	usb_free_urb(kbd->led);
 	usb_buffer_free(dev, 8, kbd->new, kbd->new_dma);
-	usb_buffer_free(dev, sizeof(struct usb_ctrlrequest), kbd->cr, kbd->cr_dma);
+	kfree(kbd->cr);
 	usb_buffer_free(dev, 1, kbd->leds, kbd->leds_dma);
 }
 
@@ -304,9 +303,8 @@ static int usb_kbd_probe(struct usb_interface *iface,
 	usb_fill_control_urb(kbd->led, dev, usb_sndctrlpipe(dev, 0),
 			     (void *) kbd->cr, kbd->leds, 1,
 			     usb_kbd_led, kbd);
-	kbd->led->setup_dma = kbd->cr_dma;
 	kbd->led->transfer_dma = kbd->leds_dma;
-	kbd->led->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP);
+	kbd->led->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 
 	error = input_register_device(kbd->dev);
 	if (error)