On Wed, Apr 20, 2011 at 02:02:41PM +0800, Bob Liu wrote:
> ---------- Forwarded message ----------
Forwarding broke tabs.
> @@ -445,6 +446,20 @@ int uvc_queue_mmap(struct uvc_video_queue *queue,
> struct vm_area_struct *vma)
> ? ? ? ? ? ? ? ?addr += PAGE_SIZE;
> ? ? ? ? ? ? ? ?size -= PAGE_SIZE;
> ? ? ? ?}
> +#else
> + ? ? ? if (i == queue->count ||
> + ? ? ? ? ? ? ? ? ? ? ? PAGE_ALIGN(size) != queue->buf_size) {
Why do you need to round up size on nommu?
> + ? ? ? ? ? ? ? ret = -EINVAL;
> + ? ? ? ? ? ? ? goto done;
> + ? ? ? }
> +
> + ? ? ? /* documentation/nommu-mmap.txt */
I don't see where Documentation/nommu-mmap.txt provides any information
on the following line(s).
> + ? ? ? vma->vm_flags |= VM_IO | VM_MAYSHARE;
> +
> + ? ? ? addr = (unsigned long)queue->mem + buffer->buf.m.offset;
> + ? ? ? vma->vm_start = addr;
> + ? ? ? vma->vm_end = addr + ?queue->buf_size;
You don't need to do this here. vm_start and vm_end have already been
modified like this by do_mmap_pgoff after get_unmapped_area had been
called.
> +#endif
>
> ? ? ? ?vma->vm_ops = &uvc_vm_ops;
> ? ? ? ?vma->vm_private_data = buffer;
> @@ -489,6 +504,38 @@ done:
> ?}
>
> ?/*
> + * Get unmapped area.
> + *
> + * NO-MMU arch need this function to make mmap() work correctly.
> + */
> +unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
> + ? ? ? ? ? ? ? unsigned long addr, unsigned long len, unsigned long pgoff)
> +{
> + ? ? ? struct uvc_buffer *buffer;
> + ? ? ? unsigned int i;
> + ? ? ? int ret = 0;
ret should be an unsigned long. You later try to store a pointer in
there.
> +
> + ? ? ? mutex_lock(&queue->mutex);
> + ? ? ? for (i = 0; i < queue->count; ++i) {
> + ? ? ? ? ? ? ? buffer = &queue->buffer[i];
> + ? ? ? ? ? ? ? if ((buffer->buf.m.offset >> PAGE_SHIFT) == pgoff)
> + ? ? ? ? ? ? ? ? ? ? ? break;
> + ? ? ? }
> +
> + ? ? ? if (i == queue->count ||
> + ? ? ? ? ? ? ? ? ? ? ? PAGE_ALIGN(len) != queue->buf_size) {
> + ? ? ? ? ? ? ? ret = -EINVAL;
> + ? ? ? ? ? ? ? goto done;
> + ? ? ? }
> +
> + ? ? ? addr = (unsigned long)queue->mem + buffer->buf.m.offset;
> + ? ? ? ret = addr;
> +done:
> + ? ? ? mutex_unlock(&queue->mutex);
> + ? ? ? return ret;
> +}
> +
> +/*
> ?* Enable or disable the video buffers queue.
> ?*
> ?* The queue must be enabled before starting video acquisition and must be
> diff --git a/drivers/media/video/uvc/uvc_v4l2.c
> b/drivers/media/video/uvc/uvc_v4l2.c
> index 9005a8d..9efab61 100644
> --- a/drivers/media/video/uvc/uvc_v4l2.c
> +++ b/drivers/media/video/uvc/uvc_v4l2.c
> @@ -1081,6 +1081,18 @@ static unsigned int uvc_v4l2_poll(struct file
> *file, poll_table *wait)
> ? ? ? ?return uvc_queue_poll(&stream->queue, file, wait);
> ?}
>
> +static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
> + ? ? ? ? ? ? ? unsigned long addr, unsigned long len, unsigned long pgoff,
> + ? ? ? ? ? ? ? unsigned long flags)
> +{
> + ? ? ? struct uvc_fh *handle = file->private_data;
> + ? ? ? struct uvc_streaming *stream = handle->stream;
> +
> + ? ? ? uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_get_unmapped_area\n");
> +
> + ? ? ? return uvc_queue_get_unmapped_area(&stream->queue, addr, len, pgoff);
> +}
> +
> ?const struct v4l2_file_operations uvc_fops = {
> ? ? ? ?.owner ? ? ? ? ?= THIS_MODULE,
> ? ? ? ?.open ? ? ? ? ? = uvc_v4l2_open,
> @@ -1089,5 +1101,6 @@ const struct v4l2_file_operations uvc_fops = {
> ? ? ? ?.read ? ? ? ? ? = uvc_v4l2_read,
> ? ? ? ?.mmap ? ? ? ? ? = uvc_v4l2_mmap,
> ? ? ? ?.poll ? ? ? ? ? = uvc_v4l2_poll,
> + ? ? ? .get_unmapped_area = uvc_v4l2_get_unmapped_area,
> ?};
>
> diff --git a/drivers/media/video/uvc/uvcvideo.h
> b/drivers/media/video/uvc/uvcvideo.h
> index 45f01e7..48a2378 100644
> --- a/drivers/media/video/uvc/uvcvideo.h
> +++ b/drivers/media/video/uvc/uvcvideo.h
> @@ -580,6 +580,12 @@ extern int uvc_queue_mmap(struct uvc_video_queue *queue,
> ? ? ? ? ? ? ? ?struct vm_area_struct *vma);
> ?extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
> ? ? ? ? ? ? ? ?struct file *file, poll_table *wait);
> +#ifdef CONFIG_MMU
> +#define uvc_queue_get_unmapped_area NULL
> +#else
> +extern unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
> + ? ? ? ? ? ? ? unsigned long addr, unsigned long len, unsigned long pgoff);
> +#endif
> ?extern int uvc_queue_allocated(struct uvc_video_queue *queue);
> ?static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
> ?{
> diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
Rest looks good.
Did you change anything in the generic code or is this a plain
git revert c29fcff3daafbf46d64a543c1950bbd206ad8c1c
?
Maybe one can unify the mmu and nommu versions of uvc_queue_mmap by using
remap_vmalloc_range but IMHO the nommu versions of the remap_*_range
functions are broken and should only validate if the source and destination
addresses match.
Daniel