Re: [PATCH v13 59/70] mm/mremap: use vma_find_intersection() instead of vma linked list

[Davidlohr Bueso]

On Mon, 22 Aug 2022, Liam Howlett wrote:

> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>

-ENOCHANGELOG

> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>

Reviewed-by: Davidlohr Bueso <dave@xxxxxxxxxxxx>

> ---
> mm/mremap.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/mm/mremap.c b/mm/mremap.c
> index e0fba9004246..8644ff278f02 100644
> --- a/mm/mremap.c
> +++ b/mm/mremap.c
> @@ -716,7 +716,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
> 	if (excess) {
> 		vma->vm_flags |= VM_ACCOUNT;
> 		if (split)
> -			vma->vm_next->vm_flags |= VM_ACCOUNT;
> +			find_vma(mm, vma->vm_end)->vm_flags |= VM_ACCOUNT;
> 	}
>
> 	return new_addr;
> @@ -866,9 +866,10 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
> static int vma_expandable(struct vm_area_struct *vma, unsigned long delta)
> {
> 	unsigned long end = vma->vm_end + delta;
> +
> 	if (end < vma->vm_end) /* overflow */
> 		return 0;
> -	if (vma->vm_next && vma->vm_next->vm_start < end) /* intersection */
> +	if (find_vma_intersection(vma->vm_mm, vma->vm_end, end))
> 		return 0;
> 	if (get_unmapped_area(NULL, vma->vm_start, end - vma->vm_start,
> 			      0, MAP_FIXED) & ~PAGE_MASK)
>
> --
> 2.35.1