2.6.26 -stable review patch. If anyone has any objections, please let us know. ------------------ From: Laurent Pinchart (cherry picked from commit e01117c81676dc9897f567e32cdc13a26e85280b) V4L: uvcvideo: Don't free URB buffers on suspend. All submitted URBs must be killed at suspend time, but URB buffers don't have to be freed. Avoiding a free on suspend/reallocate on resume lowers the pressure on system memory. Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Michael Krufky Signed-off-by: Greg Kroah-Hartman --- drivers/media/video/uvc/uvc_video.c | 96 ++++++++++++++++++++++++------------ drivers/media/video/uvc/uvcvideo.h | 2 2 files changed, 66 insertions(+), 32 deletions(-) --- a/drivers/media/video/uvc/uvc_video.c +++ b/drivers/media/video/uvc/uvc_video.c @@ -554,9 +554,56 @@ static void uvc_video_complete(struct ur } /* + * Free transfer buffers. + */ +static void uvc_free_urb_buffers(struct uvc_video_device *video) +{ + unsigned int i; + + for (i = 0; i < UVC_URBS; ++i) { + if (video->urb_buffer[i]) { + usb_buffer_free(video->dev->udev, video->urb_size, + video->urb_buffer[i], video->urb_dma[i]); + video->urb_buffer[i] = NULL; + } + } + + video->urb_size = 0; +} + +/* + * Allocate transfer buffers. This function can be called with buffers + * already allocated when resuming from suspend, in which case it will + * return without touching the buffers. + * + * Return 0 on success or -ENOMEM when out of memory. + */ +static int uvc_alloc_urb_buffers(struct uvc_video_device *video, + unsigned int size) +{ + unsigned int i; + + /* Buffers are already allocated, bail out. */ + if (video->urb_size) + return 0; + + for (i = 0; i < UVC_URBS; ++i) { + video->urb_buffer[i] = usb_buffer_alloc(video->dev->udev, + size, GFP_KERNEL, &video->urb_dma[i]); + if (video->urb_buffer[i] == NULL) { + uvc_free_urb_buffers(video); + return -ENOMEM; + } + } + + video->urb_size = size; + return 0; +} + +/* * Uninitialize isochronous/bulk URBs and free transfer buffers. */ -static void uvc_uninit_video(struct uvc_video_device *video) +static void uvc_uninit_video(struct uvc_video_device *video, int free_buffers) { struct urb *urb; unsigned int i; @@ -566,19 +613,12 @@ static void uvc_uninit_video(struct uvc_ continue; usb_kill_urb(urb); - /* urb->transfer_buffer_length is not touched by USB core, so - * we can use it here as the buffer length. - */ - if (video->urb_buffer[i]) { - usb_buffer_free(video->dev->udev, - urb->transfer_buffer_length, - video->urb_buffer[i], urb->transfer_dma); - video->urb_buffer[i] = NULL; - } - usb_free_urb(urb); video->urb[i] = NULL; } + + if (free_buffers) + uvc_free_urb_buffers(video); } /* @@ -610,18 +650,13 @@ static int uvc_init_video_isoc(struct uv size = npackets * psize; + if (uvc_alloc_urb_buffers(video, size) < 0) + return -ENOMEM; + for (i = 0; i < UVC_URBS; ++i) { urb = usb_alloc_urb(npackets, gfp_flags); if (urb == NULL) { - uvc_uninit_video(video); - return -ENOMEM; - } - - video->urb_buffer[i] = usb_buffer_alloc(video->dev->udev, - size, gfp_flags, &urb->transfer_dma); - if (video->urb_buffer[i] == NULL) { - usb_free_urb(urb); - uvc_uninit_video(video); + uvc_uninit_video(video, 1); return -ENOMEM; } @@ -632,6 +667,7 @@ static int uvc_init_video_isoc(struct uv urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; urb->interval = ep->desc.bInterval; urb->transfer_buffer = video->urb_buffer[i]; + urb->transfer_dma = video->urb_dma[i]; urb->complete = uvc_video_complete; urb->number_of_packets = npackets; urb->transfer_buffer_length = size; @@ -671,20 +707,15 @@ static int uvc_init_video_bulk(struct uv if (size > psize * UVC_MAX_ISO_PACKETS) size = psize * UVC_MAX_ISO_PACKETS; + if (uvc_alloc_urb_buffers(video, size) < 0) + return -ENOMEM; + pipe = usb_rcvbulkpipe(video->dev->udev, ep->desc.bEndpointAddress); for (i = 0; i < UVC_URBS; ++i) { urb = usb_alloc_urb(0, gfp_flags); if (urb == NULL) { - uvc_uninit_video(video); - return -ENOMEM; - } - - video->urb_buffer[i] = usb_buffer_alloc(video->dev->udev, - size, gfp_flags, &urb->transfer_dma); - if (video->urb_buffer[i] == NULL) { - usb_free_urb(urb); - uvc_uninit_video(video); + uvc_uninit_video(video, 1); return -ENOMEM; } @@ -692,6 +723,7 @@ static int uvc_init_video_bulk(struct uv video->urb_buffer[i], size, uvc_video_complete, video); urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; + urb->transfer_dma = video->urb_dma[i]; video->urb[i] = urb; } @@ -766,7 +798,7 @@ static int uvc_init_video(struct uvc_vid if ((ret = usb_submit_urb(video->urb[i], gfp_flags)) < 0) { uvc_printk(KERN_ERR, "Failed to submit URB %u " "(%d).\n", i, ret); - uvc_uninit_video(video); + uvc_uninit_video(video, 1); return ret; } } @@ -791,7 +823,7 @@ int uvc_video_suspend(struct uvc_video_d return 0; video->frozen = 1; - uvc_uninit_video(video); + uvc_uninit_video(video, 0); usb_set_interface(video->dev->udev, video->streaming->intfnum, 0); return 0; } @@ -920,7 +952,7 @@ int uvc_video_enable(struct uvc_video_de int ret; if (!enable) { - uvc_uninit_video(video); + uvc_uninit_video(video, 1); usb_set_interface(video->dev->udev, video->streaming->intfnum, 0); uvc_queue_enable(&video->queue, 0); --- a/drivers/media/video/uvc/uvcvideo.h +++ b/drivers/media/video/uvc/uvcvideo.h @@ -602,6 +602,8 @@ struct uvc_video_device { struct urb *urb[UVC_URBS]; char *urb_buffer[UVC_URBS]; + dma_addr_t urb_dma[UVC_URBS]; + unsigned int urb_size; __u8 last_fid; }; -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/