mm/khugepaged: use ALIGN helpers for PMD alignment

PMD alignment in khugepaged is currently implemented using a mix of
rounding helpers and open-coded bitmask operations.

Use ALIGN() and ALIGN_DOWN() consistently for PMD-sized address range
alignment, matching the preferred style for address and size handling.

No functional change intended.

Link: https://lore.kernel.org/20260409014323.2385982-1-ye.liu@linux.dev
Signed-off-by: Ye Liu <liuye@kylinos.cn>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam@infradead.org>
Cc: Liu Ye <liuye@kylinos.cn>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index b8452dbdb043f823ffcca8838a833e808f158a26..5f4e009593e011628c2ffad2d458528c57e97c38 100644 (file)
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2528,8 +2528,8 @@ static void collapse_scan_mm_slot(unsigned int progress_max,
                        cc->progress++;
                        continue;
                }
-               hstart = round_up(vma->vm_start, HPAGE_PMD_SIZE);
-               hend = round_down(vma->vm_end, HPAGE_PMD_SIZE);
+               hstart = ALIGN(vma->vm_start, HPAGE_PMD_SIZE);
+               hend = ALIGN_DOWN(vma->vm_end, HPAGE_PMD_SIZE);
                if (khugepaged_scan.address > hend) {
                        cc->progress++;
                        continue;
@@ -2845,8 +2845,8 @@ int madvise_collapse(struct vm_area_struct *vma, unsigned long start,
        mmgrab(mm);
        lru_add_drain_all();
 
-       hstart = (start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
-       hend = end & HPAGE_PMD_MASK;
+       hstart = ALIGN(start, HPAGE_PMD_SIZE);
+       hend = ALIGN_DOWN(end, HPAGE_PMD_SIZE);
 
        for (addr = hstart; addr < hend; addr += HPAGE_PMD_SIZE) {
                enum scan_result result = SCAN_FAIL;