Hi Souptick,
On 2019-01-31 04:13, Souptick Joarder wrote:
> Convert to use vm_insert_range to map range of kernel memory
> to user vma.
>
> vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer,
> not as a in-buffer offset by design and it always want to mmap a
> whole buffer from its beginning.
>
> Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx>
Suggested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Reviewed-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> ---
> drivers/media/common/videobuf2/videobuf2-core.c | 7 +++++++
> .../media/common/videobuf2/videobuf2-dma-contig.c | 6 ------
> drivers/media/common/videobuf2/videobuf2-dma-sg.c | 22 ++++++----------------
> 3 files changed, 13 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index 70e8c33..ca4577a 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -2175,6 +2175,13 @@ int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
> goto unlock;
> }
>
> + /*
> + * vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer,
> + * not as a in-buffer offset. We always want to mmap a whole buffer
> + * from its beginning.
> + */
> + vma->vm_pgoff = 0;
> +
> ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma);
>
> unlock:
> diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> index aff0ab7..46245c5 100644
> --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> @@ -186,12 +186,6 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma)
> return -EINVAL;
> }
>
> - /*
> - * dma_mmap_* uses vm_pgoff as in-buffer offset, but we want to
> - * map whole buffer
> - */
> - vma->vm_pgoff = 0;
> -
> ret = dma_mmap_attrs(buf->dev, vma, buf->cookie,
> buf->dma_addr, buf->size, buf->attrs);
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> index 015e737..a800200 100644
> --- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> +++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> @@ -328,28 +328,18 @@ static unsigned int vb2_dma_sg_num_users(void *buf_priv)
> static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma)
> {
> struct vb2_dma_sg_buf *buf = buf_priv;
> - unsigned long uaddr = vma->vm_start;
> - unsigned long usize = vma->vm_end - vma->vm_start;
> - int i = 0;
> + int err;
>
> if (!buf) {
> printk(KERN_ERR "No memory to map\n");
> return -EINVAL;
> }
>
> - do {
> - int ret;
> -
> - ret = vm_insert_page(vma, uaddr, buf->pages[i++]);
> - if (ret) {
> - printk(KERN_ERR "Remapping memory, error: %d\n", ret);
> - return ret;
> - }
> -
> - uaddr += PAGE_SIZE;
> - usize -= PAGE_SIZE;
> - } while (usize > 0);
> -
> + err = vm_insert_range(vma, buf->pages, buf->num_pages);
> + if (err) {
> + printk(KERN_ERR "Remapping memory, error: %d\n", err);
> + return err;
> + }
>
> /*
> * Use common vm_area operations to track buffer refcount.
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
