Re: [PATCH v1 03/16] mm/memory: inline unmap_mapping_range_vma() into unmap_mapping_range_tree()

Lorenzo Stoakes (Oracle)
2026-03-06T12:24:56Z

On Fri, Feb 27, 2026 at 09:08:34PM +0100, David Hildenbrand (Arm) wrote:
> Let's remove the number of unmap-related functions that cause confusion
> by inlining unmap_mapping_range_vma() into its single caller. The end
> result looks pretty readable.
>
> Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>

Yeah that's fine, and while I usually like having lots of smaller functions to
break up logic, I always felt when reading it that the zap logic had _too many_
so this is welcome.

LGTM, so:

Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>

> ---
> mm/memory.c | 23 +++++++----------------
> 1 file changed, 7 insertions(+), 16 deletions(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index 19f5f9a60995..5c47309331f5 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -4221,18 +4221,6 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf)
> return wp_page_copy(vmf);
> }
>
> -static void unmap_mapping_range_vma(struct vm_area_struct *vma,
> - unsigned long start_addr, unsigned long end_addr,
> - struct zap_details *details)
> -{
> - struct mmu_gather tlb;
> -
> - tlb_gather_mmu(&tlb, vma->vm_mm);
> - zap_page_range_single_batched(&tlb, vma, start_addr,
> - end_addr - start_addr, details);
> - tlb_finish_mmu(&tlb);
> -}
> -
> static inline void unmap_mapping_range_tree(struct rb_root_cached *root,
> pgoff_t first_index,
> pgoff_t last_index,
> @@ -4240,17 +4228,20 @@ static inline void unmap_mapping_range_tree(struct rb_root_cached *root,
> {
> struct vm_area_struct *vma;
> pgoff_t vba, vea, zba, zea;
> + unsigned long start, size;
> + struct mmu_gather tlb;
>
> vma_interval_tree_foreach(vma, root, first_index, last_index) {
> vba = vma->vm_pgoff;
> vea = vba + vma_pages(vma) - 1;
> zba = max(first_index, vba);
> zea = min(last_index, vea);
> + start = ((zba - vba) << PAGE_SHIFT) + vma->vm_start;
> + size = (zea - zba + 1) << PAGE_SHIFT;
>
> - unmap_mapping_range_vma(vma,
> - ((zba - vba) << PAGE_SHIFT) + vma->vm_start,
> - ((zea - vba + 1) << PAGE_SHIFT) + vma->vm_start,
> - details);
> + tlb_gather_mmu(&tlb, vma->vm_mm);
> + zap_page_range_single_batched(&tlb, vma, start, size, details);
> + tlb_finish_mmu(&tlb);
> }
> }
>
> --
> 2.43.0
>