[RFC PATCH v2 13/47] hugetlb: add make_huge_pte_with_shift

From: James Houghton
Date: Fri Oct 21 2022 - 12:38:28 EST


This allows us to make huge PTEs at shifts other than the hstate shift,
which will be necessary for high-granularity mappings.

Signed-off-by: James Houghton <jthoughton@xxxxxxxxxx>
---
mm/hugetlb.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 90db59632559..74a4afda1a7e 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4867,11 +4867,11 @@ const struct vm_operations_struct hugetlb_vm_ops = {
.pagesize = hugetlb_vm_op_pagesize,
};

-static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
- int writable)
+static pte_t make_huge_pte_with_shift(struct vm_area_struct *vma,
+ struct page *page, int writable,
+ int shift)
{
pte_t entry;
- unsigned int shift = huge_page_shift(hstate_vma(vma));

if (writable) {
entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_pte(page,
@@ -4885,6 +4885,14 @@ static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
return entry;
}

+static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page,
+ int writable)
+{
+ unsigned int shift = huge_page_shift(hstate_vma(vma));
+
+ return make_huge_pte_with_shift(vma, page, writable, shift);
+}
+
static void set_huge_ptep_writable(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
{
--
2.38.0.135.g90850a2211-goog