Commit 77a22f6f authored by Kefeng Wang's avatar Kefeng Wang
Browse files

mm: convert to should_zap_page() to should_zap_folio() 

mainline inclusion
from mainline-v6.9-rc1
commit eabafaaa957553142cdafc8ae804fb679e5a5f5e
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I9CHB4
CVE: NA

-------------------------------------------------

Make should_zap_page() take a folio and rename it to should_zap_folio() as
preparation for converting mm counter functions to take a folio.  Saves a
call to compound_head() hidden inside PageAnon().

[wangkefeng.wang@huawei.com: fix used-uninitialized warning]
  Link: https://lkml.kernel.org/r/962a7993-fce9-4de8-85cd-25e290f25736@huawei.com
Link: https://lkml.kernel.org/r/20240111152429.3374566-9-willy@infradead.org


Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
(cherry picked from commit eabafaaa957553142cdafc8ae804fb679e5a5f5e)
Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
parent 5631505d

mm/memory.c

+17 −14
Original line number Diff line number Diff line
@@ -1370,19 +1370,20 @@ static inline bool should_zap_cows(struct zap_details *details) 
	return details->even_cows;

}



/* Decides whether we should zap this page with the page pointer specified */

static inline bool should_zap_page(struct zap_details *details, struct page *page)

/* Decides whether we should zap this folio with the folio pointer specified */

static inline bool should_zap_folio(struct zap_details *details,

				    struct folio *folio)

{

	/* If we can make a decision without *page.. */

	/* If we can make a decision without *folio.. */

	if (should_zap_cows(details))

		return true;



	/* E.g. the caller passes NULL for the case of a zero page */

	if (!page)

	/* E.g. the caller passes NULL for the case of a zero folio */

	if (!folio)

		return true;



	/* Otherwise we should only zap non-anon pages */

	return !PageAnon(page);

	/* Otherwise we should only zap non-anon folios */

	return !folio_test_anon(folio);

}



static inline bool zap_drop_file_uffd_wp(struct zap_details *details)
@@ -1435,7 +1436,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, 
	arch_enter_lazy_mmu_mode();

	do {

		pte_t ptent = ptep_get(pte);

		struct folio *folio;

		struct folio *folio = NULL;

		struct page *page;



		if (pte_none(ptent))
@@ -1448,7 +1449,10 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, 
			unsigned int delay_rmap;



			page = vm_normal_page(vma, addr, ptent);

			if (unlikely(!should_zap_page(details, page)))

			if (page)

				folio = page_folio(page);



			if (unlikely(!should_zap_folio(details, folio)))

				continue;

			ptent = ptep_get_and_clear_full(mm, addr, pte,

							tlb->fullmm);
@@ -1461,7 +1465,6 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, 
				continue;

			}



			folio = page_folio(page);

			delay_rmap = 0;

			if (!folio_test_anon(folio)) {

				if (pte_dirty(ptent)) {
@@ -1494,7 +1497,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, 
		    is_device_exclusive_entry(entry)) {

			page = pfn_swap_entry_to_page(entry);

			folio = page_folio(page);

			if (unlikely(!should_zap_page(details, page)))

			if (unlikely(!should_zap_folio(details, folio)))

				continue;

			/*

			 * Both device private/exclusive mappings should only
@@ -1516,10 +1519,10 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, 
			if (unlikely(!free_swap_and_cache(entry)))

				print_bad_pte(vma, addr, ptent, NULL);

		} else if (is_migration_entry(entry)) {

			page = pfn_swap_entry_to_page(entry);

			if (!should_zap_page(details, page))

			folio = pfn_swap_entry_folio(entry);

			if (!should_zap_folio(details, folio))

				continue;

			rss[mm_counter(page)]--;

			rss[mm_counter(&folio->page)]--;

		} else if (pte_marker_entry_uffd_wp(entry)) {

			/*

			 * For anon: always drop the marker; for file: only