[PATCH RFC 06/13] mm/rmap: pass rmap flags to hugepage_add_anon_rmap()

David Hildenbrand
2022-02-24T12:30:10Z

Let's prepare for passing RMAP_EXCLUSIVE, similarly as we do for
page_add_anon_rmap() now. RMAP_COMPOUND is implicit for hugetlb
pages and ignored.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
include/linux/rmap.h | 2 +-
mm/migrate.c | 2 +-
mm/rmap.c | 8 +++++---
3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index f230e86b4587..593a4566420f 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -174,7 +174,7 @@ void page_add_file_rmap(struct page *, bool);
void page_remove_rmap(struct page *, bool);

void hugepage_add_anon_rmap(struct page *, struct vm_area_struct *,
- unsigned long);
+ unsigned long, int);
void hugepage_add_new_anon_rmap(struct page *, struct vm_area_struct *,
unsigned long);

diff --git a/mm/migrate.c b/mm/migrate.c
index d4d72a15224c..709cb11d5b81 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -238,7 +238,7 @@ static bool remove_migration_pte(struct page *page, struct vm_area_struct *vma,
pte = pte_mkhuge(pte);
pte = arch_make_huge_pte(pte, shift, vma->vm_flags);
if (PageAnon(new))
- hugepage_add_anon_rmap(new, vma, pvmw.address);
+ hugepage_add_anon_rmap(new, vma, pvmw.address, 0);
else
page_dup_file_rmap(new, true);
set_huge_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte);
diff --git a/mm/rmap.c b/mm/rmap.c
index 902ebf99d147..bafdb7f70cec 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -2409,9 +2409,11 @@ void rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc)
* The following two functions are for anonymous (private mapped) hugepages.
* Unlike common anonymous pages, anonymous hugepages have no accounting code
* and no lru code, because we handle hugepages differently from common pages.
+ *
+ * RMAP_COMPOUND is ignored.
*/
-void hugepage_add_anon_rmap(struct page *page,
- struct vm_area_struct *vma, unsigned long address)
+void hugepage_add_anon_rmap(struct page *page, struct vm_area_struct *vma,
+ unsigned long address, int flags)
{
struct anon_vma *anon_vma = vma->anon_vma;
int first;
@@ -2421,7 +2423,7 @@ void hugepage_add_anon_rmap(struct page *page,
/* address might be in next vma when migration races vma_adjust */
first = atomic_inc_and_test(compound_mapcount_ptr(page));
if (first)
- __page_set_anon_rmap(page, vma, address, 0);
+ __page_set_anon_rmap(page, vma, address, flags & RMAP_EXCLUSIVE);
}

void hugepage_add_new_anon_rmap(struct page *page,
--
2.35.1