Re: [PATCH v4 35/66] optee: Remove vma linked list walk

[Vlastimil Babka]

On 12/1/21 15:30, Liam Howlett wrote:
> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
> 
> Use the VMA iterator instead.  Change the calling convention of
> __check_mem_type() to pass in the mm instead of the first vma in the
> range.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>

Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

> ---
>  drivers/tee/optee/call.c | 18 ++++++++++--------
>  1 file changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c
> index b25cc1fac945..177575c445de 100644
> --- a/drivers/tee/optee/call.c
> +++ b/drivers/tee/optee/call.c
> @@ -342,15 +342,18 @@ static bool is_normal_memory(pgprot_t p)
>  #endif
>  }
>  
> -static int __check_mem_type(struct vm_area_struct *vma, unsigned long end)
> +static int __check_mem_type(struct mm_struct *mm, unsigned long start,
> +				unsigned long end)
>  {
> -	while (vma && is_normal_memory(vma->vm_page_prot)) {
> -		if (vma->vm_end >= end)
> -			return 0;
> -		vma = vma->vm_next;
> +	struct vm_area_struct *vma;
> +	VMA_ITERATOR(vmi, mm, start);
> +
> +	for_each_vma_range(vmi, vma, end) {
> +		if (!is_normal_memory(vma->vm_page_prot))
> +			return -EINVAL;
>  	}
>  
> -	return -EINVAL;
> +	return 0;
>  }
>  
>  int optee_check_mem_type(unsigned long start, size_t num_pages)
> @@ -366,8 +369,7 @@ int optee_check_mem_type(unsigned long start, size_t num_pages)
>  		return 0;
>  
>  	mmap_read_lock(mm);
> -	rc = __check_mem_type(find_vma(mm, start),
> -			      start + num_pages * PAGE_SIZE);
> +	rc = __check_mem_type(mm, start, start + num_pages * PAGE_SIZE);
>  	mmap_read_unlock(mm);
>  
>  	return rc;