2018-11-15 15:48:50

by Souptick Joarder

Subject: [PATCH 7/9] videobuf2/videobuf2-dma-sg.c: Convert to use vm_insert_range

Convert to use vm_insert_range to map range of kernel memory
to user vma.

Signed-off-by: Souptick Joarder <[email protected]>
Reviewed-by: Matthew Wilcox <[email protected]>
---
drivers/media/common/videobuf2/videobuf2-dma-sg.c | 23 +++++++----------------
1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
index 015e737..898adef 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
@@ -328,28 +328,19 @@ 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;
+ unsigned long page_count = vma_pages(vma);
+ 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, vma->vm_start, buf->pages, page_count);
+ if (err) {
+ printk(KERN_ERR "Remapping memory, error: %d\n", err);
+ return err;
+ }

/*
* Use common vm_area operations to track buffer refcount.
--
1.9.1

2018-11-21 08:44:15

by Marek Szyprowski

Subject: Re: [PATCH 7/9] videobuf2/videobuf2-dma-sg.c: Convert to use vm_insert_range

Hi Souptick,

On 2018-11-15 16:50, Souptick Joarder wrote:
> Convert to use vm_insert_range to map range of kernel memory
> to user vma.
>
> Signed-off-by: Souptick Joarder <[email protected]>
> Reviewed-by: Matthew Wilcox <[email protected]>

Acked-by: Marek Szyprowski <[email protected]>

> ---
> drivers/media/common/videobuf2/videobuf2-dma-sg.c | 23 +++++++----------------
> 1 file changed, 7 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> index 015e737..898adef 100644
> --- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> +++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
> @@ -328,28 +328,19 @@ 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;
> + unsigned long page_count = vma_pages(vma);
> + 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, vma->vm_start, buf->pages, page_count);
> + 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