mm/rmap: Convert try_to_migrate() to folios
Convert the callers to pass a folio and the try_to_migrate_one()
worker to use a folio throughout. Fixes an assumption that a
folio must be <= PMD size.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
diff --git a/mm/rmap.c b/mm/rmap.c
index cf6e3de..8497da2 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1706,7 +1706,7 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
{
struct folio *folio = page_folio(page);
struct mm_struct *mm = vma->vm_mm;
- DEFINE_PAGE_VMA_WALK(pvmw, page, vma, address, 0);
+ DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, address, 0);
pte_t pteval;
struct page *subpage;
bool ret = true;
@@ -1740,7 +1740,7 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
range.end = vma_address_end(&pvmw);
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm,
address, range.end);
- if (PageHuge(page)) {
+ if (folio_test_hugetlb(folio)) {
/*
* If sharing is possible, start and end will be adjusted
* accordingly.
@@ -1754,21 +1754,24 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
/* PMD-mapped THP migration entry */
if (!pvmw.pte) {
- VM_BUG_ON_PAGE(PageHuge(page) ||
- !PageTransCompound(page), page);
+ subpage = folio_page(folio,
+ pmd_pfn(*pvmw.pmd) - folio_pfn(folio));
+ VM_BUG_ON_FOLIO(folio_test_hugetlb(folio) ||
+ !folio_test_pmd_mappable(folio), folio);
- set_pmd_migration_entry(&pvmw, page);
+ set_pmd_migration_entry(&pvmw, subpage);
continue;
}
#endif
/* Unexpected PMD-mapped THP? */
- VM_BUG_ON_PAGE(!pvmw.pte, page);
+ VM_BUG_ON_FOLIO(!pvmw.pte, folio);
- subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte);
+ subpage = folio_page(folio,
+ pte_pfn(*pvmw.pte) - folio_pfn(folio));
address = pvmw.address;
- if (PageHuge(page) && !PageAnon(page)) {
+ if (folio_test_hugetlb(folio) && !folio_test_anon(folio)) {
/*
* To call huge_pmd_unshare, i_mmap_rwsem must be
* held in write mode. Caller needs to explicitly
@@ -1806,15 +1809,15 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
flush_cache_page(vma, address, pte_pfn(*pvmw.pte));
pteval = ptep_clear_flush(vma, address, pvmw.pte);
- /* Move the dirty bit to the page. Now the pte is gone. */
+ /* Set the dirty flag on the folio now the pte is gone. */
if (pte_dirty(pteval))
- set_page_dirty(page);
+ folio_mark_dirty(folio);
/* Update high watermark before we lower rss */
update_hiwater_rss(mm);
- if (is_zone_device_page(page)) {
- unsigned long pfn = page_to_pfn(page);
+ if (folio_is_zone_device(folio)) {
+ unsigned long pfn = folio_pfn(folio);
swp_entry_t entry;
pte_t swp_pte;
@@ -1850,16 +1853,16 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
* changed when hugepage migrations to device private
* memory are supported.
*/
- subpage = page;
- } else if (PageHWPoison(page)) {
+ subpage = &folio->page;
+ } else if (PageHWPoison(subpage)) {
pteval = swp_entry_to_pte(make_hwpoison_entry(subpage));
- if (PageHuge(page)) {
- hugetlb_count_sub(compound_nr(page), mm);
+ if (folio_test_hugetlb(folio)) {
+ hugetlb_count_sub(folio_nr_pages(folio), mm);
set_huge_swap_pte_at(mm, address,
pvmw.pte, pteval,
vma_mmu_pagesize(vma));
} else {
- dec_mm_counter(mm, mm_counter(page));
+ dec_mm_counter(mm, mm_counter(&folio->page));
set_pte_at(mm, address, pvmw.pte, pteval);
}
@@ -1874,7 +1877,7 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
* migration) will not expect userfaults on already
* copied pages.
*/
- dec_mm_counter(mm, mm_counter(page));
+ dec_mm_counter(mm, mm_counter(&folio->page));
/* We have to invalidate as we cleared the pte */
mmu_notifier_invalidate_range(mm, address,
address + PAGE_SIZE);
@@ -1920,10 +1923,10 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
*
* See Documentation/vm/mmu_notifier.rst
*/
- page_remove_rmap(subpage, vma, PageHuge(page));
+ page_remove_rmap(subpage, vma, folio_test_hugetlb(folio));
if (vma->vm_flags & VM_LOCKED)
mlock_page_drain(smp_processor_id());
- put_page(page);
+ folio_put(folio);
}
mmu_notifier_invalidate_range_end(&range);
@@ -1933,13 +1936,13 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma,
/**
* try_to_migrate - try to replace all page table mappings with swap entries
- * @page: the page to replace page table entries for
+ * @folio: the folio to replace page table entries for
* @flags: action and flags
*
- * Tries to remove all the page table entries which are mapping this page and
- * replace them with special swap entries. Caller must hold the page lock.
+ * Tries to remove all the page table entries which are mapping this folio and
+ * replace them with special swap entries. Caller must hold the folio lock.
*/
-void try_to_migrate(struct page *page, enum ttu_flags flags)
+void try_to_migrate(struct folio *folio, enum ttu_flags flags)
{
struct rmap_walk_control rwc = {
.rmap_one = try_to_migrate_one,
@@ -1956,7 +1959,7 @@ void try_to_migrate(struct page *page, enum ttu_flags flags)
TTU_SYNC)))
return;
- if (is_zone_device_page(page) && !is_device_private_page(page))
+ if (folio_is_zone_device(folio) && !folio_is_device_private(folio))
return;
/*
@@ -1967,13 +1970,13 @@ void try_to_migrate(struct page *page, enum ttu_flags flags)
* locking requirements of exec(), migration skips
* temporary VMAs until after exec() completes.
*/
- if (!PageKsm(page) && PageAnon(page))
+ if (!folio_test_ksm(folio) && folio_test_anon(folio))
rwc.invalid_vma = invalid_migration_vma;
if (flags & TTU_RMAP_LOCKED)
- rmap_walk_locked(page, &rwc);
+ rmap_walk_locked(&folio->page, &rwc);
else
- rmap_walk(page, &rwc);
+ rmap_walk(&folio->page, &rwc);
}
#ifdef CONFIG_DEVICE_PRIVATE
