hugetlb: convert hugetlb_vma_maps_page() to hugetlb_vma_maps_pfn()

pte_page() is more expensive than pte_pfn() (often it's defined as
pfn_to_page(pte_pfn())), so it makes sense to do the conversion to pfn
once (by calling folio_pfn()) rather than convert the pfn to a page each
time.

While this is a very small advantage, the main motivation is removing a
reference to folio->page.

Link: https://lkml.kernel.org/r/20250226163131.3795869-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 0fc179a598300c6a24edaa7633bbf9b9a2d7bee2..a427d41fbca08a29712ca8ad071a90366107eae2 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -338,8 +338,8 @@ static void hugetlb_delete_from_page_cache(struct folio *folio)
  * mutex for the page in the mapping.  So, we can not race with page being
  * faulted into the vma.
  */
-static bool hugetlb_vma_maps_page(struct vm_area_struct *vma,
-                               unsigned long addr, struct page *page)
+static bool hugetlb_vma_maps_pfn(struct vm_area_struct *vma,
+                               unsigned long addr, unsigned long pfn)
 {
        pte_t *ptep, pte;
 
@@ -351,7 +351,7 @@ static bool hugetlb_vma_maps_page(struct vm_area_struct *vma,
        if (huge_pte_none(pte) || !pte_present(pte))
                return false;
 
-       if (pte_page(pte) == page)
+       if (pte_pfn(pte) == pfn)
                return true;
 
        return false;
@@ -396,7 +396,7 @@ static void hugetlb_unmap_file_folio(struct hstate *h,
 {
        struct rb_root_cached *root = &mapping->i_mmap;
        struct hugetlb_vma_lock *vma_lock;
-       struct page *page = &folio->page;
+       unsigned long pfn = folio_pfn(folio);
        struct vm_area_struct *vma;
        unsigned long v_start;
        unsigned long v_end;
@@ -412,7 +412,7 @@ retry:
                v_start = vma_offset_start(vma, start);
                v_end = vma_offset_end(vma, end);
 
-               if (!hugetlb_vma_maps_page(vma, v_start, page))
+               if (!hugetlb_vma_maps_pfn(vma, v_start, pfn))
                        continue;
 
                if (!hugetlb_vma_trylock_write(vma)) {
@@ -462,7 +462,7 @@ retry:
                 */
                v_start = vma_offset_start(vma, start);
                v_end = vma_offset_end(vma, end);
-               if (hugetlb_vma_maps_page(vma, v_start, page))
+               if (hugetlb_vma_maps_pfn(vma, v_start, pfn))
                        unmap_hugepage_range(vma, v_start, v_end, NULL,
                                             ZAP_FLAG_DROP_MARKER);