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USB: don't use a fixed DMA mapping for hub status URBs 

This patch (as1296) gets rid of the fixed DMA-buffer mapping used by
the hub driver for its status URB.  This URB doesn't get used much --
mainly when a device is plugged in or unplugged -- so the dynamic
mapping overhead is minimal.  And most systems have many fewer
external hubs than root hubs, which don't need a mapped buffer anyway.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern 2009-10-27 15:18:46 -04:00 committed by Greg Kroah-Hartman
parent dccd574ccc
commit d697cdda43
1 changed files with 2 additions and 7 deletions
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9
drivers/usb/core/hub.c
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@ -45,7 +45,6 @@ struct usb_hub {
/* buffer for urb ... with extra space in case of babble */
char (*buffer)[8];
dma_addr_t buffer_dma; /* DMA address for buffer */
union {
struct usb_hub_status hub;
struct usb_port_status port;
@ -869,8 +868,7 @@ static int hub_configure(struct usb_hub *hub,
int maxp, ret;
char *message = "out of memory";
hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
&hub->buffer_dma);
hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
if (!hub->buffer) {
ret = -ENOMEM;
goto fail;
@ -1111,8 +1109,6 @@ static int hub_configure(struct usb_hub *hub,
usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
hub, endpoint->bInterval);
hub->urb->transfer_dma = hub->buffer_dma;
hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
/* maybe cycle the hub leds */
if (hub->has_indicators && blinkenlights)
@ -1162,8 +1158,7 @@ static void hub_disconnect(struct usb_interface *intf)
kfree(hub->port_owners);
kfree(hub->descriptor);
kfree(hub->status);
usb_buffer_free(hub->hdev, sizeof(*hub->buffer), hub->buffer,
hub->buffer_dma);
kfree(hub->buffer);
kref_put(&hub->kref, hub_release);
}