Re: [PATCH v1 5/7] mm/pagewalk: add walk_page_range_vma()

From: David Hildenbrand
Date: Thu Oct 06 2022 - 05:35:50 EST

On 05.10.22 22:42, Peter Xu wrote:
On Fri, Sep 30, 2022 at 04:19:29PM +0200, David Hildenbrand wrote:
+int walk_page_range_vma(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end, const struct mm_walk_ops *ops,
+ void *private)
+ struct mm_walk walk = {
+ .ops = ops,
+ .mm = vma->vm_mm,
+ .vma = vma,
+ .private = private,
+ };
+ int err;
+ if (start >= end || !
+ return -EINVAL;
+ if (start < vma->vm_start || end > vma->vm_end)
+ return -EINVAL;
+ mmap_assert_locked(;
+ err = walk_page_test(start, end, &walk);

According to test_walk():

* @test_walk: caller specific callback function to determine whether
* we walk over the current vma or not. Returning 0 means
* "do page table walk over the current vma", returning
* a negative value means "abort current page table walk
* right now" and returning 1 means "skip the current vma"

Since this helper has vma passed in, not sure whether this is needed at

I kept it because walk_page_vma() similarly has it -- walk_page_vma() walks the whole VMA range.

I do agree that it's kind of weird to have it like that. All users of walk_page_vma() don't use it, so we can just get rid of it there as well. Might make the walk slightly faster.

walk_page_vma_range() sounds slightly better to me as it does look more
like an extension of walk_page_vma(), rather than sister version of
walk_page_range_novma() (which works for "no backing VMA" case). But no
strong opinion.

I matched that to walk_page_range_novma(). Now we have



David / dhildenb