[PATCH v4 07/17] mm/rmap: pass rmap flags to hugepage_add_anon_rmap()

David Hildenbrand
2022-04-28T08:38:43Z

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.

Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
include/linux/rmap.h | 2 +-
mm/migrate.c | 3 ++-
mm/rmap.c | 9 ++++++---
3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index aa734d2e2b01..f47bc937c383 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -191,7 +191,7 @@ void page_add_file_rmap(struct page *, struct vm_area_struct *,
void page_remove_rmap(struct page *, struct vm_area_struct *,
bool compound);
void hugepage_add_anon_rmap(struct page *, struct vm_area_struct *,
- unsigned long address);
+ unsigned long address, rmap_t flags);
void hugepage_add_new_anon_rmap(struct page *, struct vm_area_struct *,
unsigned long address);

diff --git a/mm/migrate.c b/mm/migrate.c
index 1e1d9519e05c..0167463ea9c5 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -232,7 +232,8 @@ static bool remove_migration_pte(struct folio *folio,
pte = pte_mkhuge(pte);
pte = arch_make_huge_pte(pte, shift, vma->vm_flags);
if (folio_test_anon(folio))
- hugepage_add_anon_rmap(new, vma, pvmw.address);
+ hugepage_add_anon_rmap(new, vma, pvmw.address,
+ RMAP_NONE);
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 ee349f905da0..065501642401 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -2347,9 +2347,11 @@ void rmap_walk_locked(struct folio *folio, const 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, rmap_t flags)
{
struct anon_vma *anon_vma = vma->anon_vma;
int first;
@@ -2359,7 +2361,8 @@ 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