2023-04-17 01:11:05

by zhangpeng (AS)

Subject: [PATCH] userfaultfd: use helper function range_in_vma()

From: ZhangPeng <[email protected]>

We could use range_in_vma() to check if dst_start, dst_start + len are
within the dst_vma range. Minor readability improvement.

Signed-off-by: ZhangPeng <[email protected]>
---
mm/userfaultfd.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 11cfd82c6726..e97a0b4889fc 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -31,11 +31,7 @@ struct vm_area_struct *find_dst_vma(struct mm_struct *dst_mm,
struct vm_area_struct *dst_vma;

dst_vma = find_vma(dst_mm, dst_start);
- if (!dst_vma)
- return NULL;
-
- if (dst_start < dst_vma->vm_start ||
- dst_start + len > dst_vma->vm_end)
+ if (!range_in_vma(dst_vma, dst_start, dst_start + len))
return NULL;

/*
--
2.25.1

2023-04-17 10:41:35

by David Hildenbrand

Subject: Re: [PATCH] userfaultfd: use helper function range_in_vma()

On 17.04.23 02:39, Peng Zhang wrote:
> From: ZhangPeng <[email protected]>
>
> We could use range_in_vma() to check if dst_start, dst_start + len are
> within the dst_vma range. Minor readability improvement.
>
> Signed-off-by: ZhangPeng <[email protected]>
> ---
> mm/userfaultfd.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
> index 11cfd82c6726..e97a0b4889fc 100644
> --- a/mm/userfaultfd.c
> +++ b/mm/userfaultfd.c
> @@ -31,11 +31,7 @@ struct vm_area_struct *find_dst_vma(struct mm_struct *dst_mm,
> struct vm_area_struct *dst_vma;
>
> dst_vma = find_vma(dst_mm, dst_start);
> - if (!dst_vma)
> - return NULL;
> -
> - if (dst_start < dst_vma->vm_start ||
> - dst_start + len > dst_vma->vm_end)
> + if (!range_in_vma(dst_vma, dst_start, dst_start + len))
> return NULL;
>
> /*

Reviewed-by: David Hildenbrand <[email protected]>

--
Thanks,

David / dhildenb