From afe823da08720ab728a75ac4d12a830d1cc73549 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 16 Sep 2008 06:32:20 +0000 Subject: V4L/DVB:usbvideo:don't use part of buffer for USB transfer #4 From: Ming Lei The status[] is part of uvc_device structure. We can't make sure the address of status is at a cache-line boundary in all archs,so status[] might share a cache-line with some fields in uvc_structure. This can lead to some cache coherence issues(http://lwn.net/Articles/2265/). Use dynamically allocated buffer instead. Signed-off-by: Ming Lei Acked-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- linux/drivers/media/video/uvc/uvc_status.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'linux/drivers/media/video/uvc/uvc_status.c') diff --git a/linux/drivers/media/video/uvc/uvc_status.c b/linux/drivers/media/video/uvc/uvc_status.c index 75e678ac5..5d60b264d 100644 --- a/linux/drivers/media/video/uvc/uvc_status.c +++ b/linux/drivers/media/video/uvc/uvc_status.c @@ -177,9 +177,15 @@ int uvc_status_init(struct uvc_device *dev) uvc_input_init(dev); + dev->status = kzalloc(UVC_MAX_STATUS_SIZE, GFP_KERNEL); + if (dev->status == NULL) + return -ENOMEM; + dev->int_urb = usb_alloc_urb(0, GFP_KERNEL); - if (dev->int_urb == NULL) + if (dev->int_urb == NULL) { + kfree(dev->status); return -ENOMEM; + } pipe = usb_rcvintpipe(dev->udev, ep->desc.bEndpointAddress); @@ -192,7 +198,7 @@ int uvc_status_init(struct uvc_device *dev) interval = fls(interval) - 1; usb_fill_int_urb(dev->int_urb, dev->udev, pipe, - dev->status, sizeof dev->status, uvc_status_complete, + dev->status, UVC_MAX_STATUS_SIZE, uvc_status_complete, dev, interval); return usb_submit_urb(dev->int_urb, GFP_KERNEL); @@ -202,6 +208,7 @@ void uvc_status_cleanup(struct uvc_device *dev) { usb_kill_urb(dev->int_urb); usb_free_urb(dev->int_urb); + kfree(dev->status); uvc_input_cleanup(dev); } -- cgit v1.2.3