The patch titled
Subject: mm: mass constification of folio/page pointers
has been added to the -mm mm-unstable branch. Its filename is
mm-mass-constification-of-folio-page-pointers.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mass-constification-of-folio-page-pointers.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: mass constification of folio/page pointers
Date: Sat, 5 Oct 2024 21:01:15 +0100
Now that page_pgoff() takes const pointers, we can constify the pointers
to a lot of functions.
Link: https://lkml.kernel.org/r/20241005200121.3231142-5-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/ksm.h | 7 ++++---
include/linux/rmap.h | 10 +++++-----
mm/internal.h | 5 +++--
mm/ksm.c | 5 +++--
mm/memory-failure.c | 24 +++++++++++++-----------
mm/page_vma_mapped.c | 5 +++--
mm/rmap.c | 11 ++++++-----
7 files changed, 37 insertions(+), 30 deletions(-)
--- a/include/linux/ksm.h~mm-mass-constification-of-folio-page-pointers
+++ a/include/linux/ksm.h
@@ -91,7 +91,7 @@ struct folio *ksm_might_need_to_copy(str
void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc);
void folio_migrate_ksm(struct folio *newfolio, struct folio *folio);
-void collect_procs_ksm(struct folio *folio, struct page *page,
+void collect_procs_ksm(const struct folio *folio, const struct page *page,
struct list_head *to_kill, int force_early);
long ksm_process_profit(struct mm_struct *);
@@ -124,8 +124,9 @@ static inline void ksm_might_unmap_zero_
{
}
-static inline void collect_procs_ksm(struct folio *folio, struct page *page,
- struct list_head *to_kill, int force_early)
+static inline void collect_procs_ksm(const struct folio *folio,
+ const struct page *page, struct list_head *to_kill,
+ int force_early)
{
}
--- a/include/linux/rmap.h~mm-mass-constification-of-folio-page-pointers
+++ a/include/linux/rmap.h
@@ -171,7 +171,7 @@ static inline void anon_vma_merge(struct
unlink_anon_vmas(next);
}
-struct anon_vma *folio_get_anon_vma(struct folio *folio);
+struct anon_vma *folio_get_anon_vma(const struct folio *folio);
/* RMAP flags, currently only relevant for some anon rmap operations. */
typedef int __bitwise rmap_t;
@@ -194,8 +194,8 @@ enum rmap_level {
RMAP_LEVEL_PMD,
};
-static inline void __folio_rmap_sanity_checks(struct folio *folio,
- struct page *page, int nr_pages, enum rmap_level level)
+static inline void __folio_rmap_sanity_checks(const struct folio *folio,
+ const struct page *page, int nr_pages, enum rmap_level level)
{
/* hugetlb folios are handled separately. */
VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio);
@@ -771,14 +771,14 @@ struct rmap_walk_control {
bool (*rmap_one)(struct folio *folio, struct vm_area_struct *vma,
unsigned long addr, void *arg);
int (*done)(struct folio *folio);
- struct anon_vma *(*anon_lock)(struct folio *folio,
+ struct anon_vma *(*anon_lock)(const struct folio *folio,
struct rmap_walk_control *rwc);
bool (*invalid_vma)(struct vm_area_struct *vma, void *arg);
};
void rmap_walk(struct folio *folio, struct rmap_walk_control *rwc);
void rmap_walk_locked(struct folio *folio, struct rmap_walk_control *rwc);
-struct anon_vma *folio_lock_anon_vma_read(struct folio *folio,
+struct anon_vma *folio_lock_anon_vma_read(const struct folio *folio,
struct rmap_walk_control *rwc);
#else /* !CONFIG_MMU */
--- a/mm/internal.h~mm-mass-constification-of-folio-page-pointers
+++ a/mm/internal.h
@@ -1072,10 +1072,11 @@ void ClearPageHWPoisonTakenOff(struct pa
bool take_page_off_buddy(struct page *page);
bool put_page_back_buddy(struct page *page);
struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);
-void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
+void add_to_kill_ksm(struct task_struct *tsk, const struct page *p,
struct vm_area_struct *vma, struct list_head *to_kill,
unsigned long ksm_addr);
-unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);
+unsigned long page_mapped_in_vma(const struct page *page,
+ struct vm_area_struct *vma);
#else
static inline void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu)
--- a/mm/ksm.c~mm-mass-constification-of-folio-page-pointers
+++ a/mm/ksm.c
@@ -1051,7 +1051,8 @@ static int unmerge_ksm_pages(struct vm_a
return err;
}
-static inline struct ksm_stable_node *folio_stable_node(struct folio *folio)
+static inline
+struct ksm_stable_node *folio_stable_node(const struct folio *folio)
{
return folio_test_ksm(folio) ? folio_raw_mapping(folio) : NULL;
}
@@ -3066,7 +3067,7 @@ again:
/*
* Collect processes when the error hit an ksm page.
*/
-void collect_procs_ksm(struct folio *folio, struct page *page,
+void collect_procs_ksm(const struct folio *folio, const struct page *page,
struct list_head *to_kill, int force_early)
{
struct ksm_stable_node *stable_node;
--- a/mm/memory-failure.c~mm-mass-constification-of-folio-page-pointers
+++ a/mm/memory-failure.c
@@ -445,7 +445,7 @@ static unsigned long dev_pagemap_mapping
* Schedule a process for later kill.
* Uses GFP_ATOMIC allocations to avoid potential recursions in the VM.
*/
-static void __add_to_kill(struct task_struct *tsk, struct page *p,
+static void __add_to_kill(struct task_struct *tsk, const struct page *p,
struct vm_area_struct *vma, struct list_head *to_kill,
unsigned long addr)
{
@@ -461,7 +461,7 @@ static void __add_to_kill(struct task_st
if (is_zone_device_page(p))
tk->size_shift = dev_pagemap_mapping_shift(vma, tk->addr);
else
- tk->size_shift = page_shift(compound_head(p));
+ tk->size_shift = folio_shift(page_folio(p));
/*
* Send SIGKILL if "tk->addr == -EFAULT". Also, as
@@ -486,7 +486,7 @@ static void __add_to_kill(struct task_st
list_add_tail(&tk->nd, to_kill);
}
-static void add_to_kill_anon_file(struct task_struct *tsk, struct page *p,
+static void add_to_kill_anon_file(struct task_struct *tsk, const struct page *p,
struct vm_area_struct *vma, struct list_head *to_kill,
unsigned long addr)
{
@@ -509,7 +509,7 @@ static bool task_in_to_kill_list(struct
return false;
}
-void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
+void add_to_kill_ksm(struct task_struct *tsk, const struct page *p,
struct vm_area_struct *vma, struct list_head *to_kill,
unsigned long addr)
{
@@ -606,8 +606,9 @@ struct task_struct *task_early_kill(stru
/*
* Collect processes when the error hit an anonymous page.
*/
-static void collect_procs_anon(struct folio *folio, struct page *page,
- struct list_head *to_kill, int force_early)
+static void collect_procs_anon(const struct folio *folio,
+ const struct page *page, struct list_head *to_kill,
+ int force_early)
{
struct task_struct *tsk;
struct anon_vma *av;
@@ -643,8 +644,9 @@ static void collect_procs_anon(struct fo
/*
* Collect processes when the error hit a file mapped page.
*/
-static void collect_procs_file(struct folio *folio, struct page *page,
- struct list_head *to_kill, int force_early)
+static void collect_procs_file(const struct folio *folio,
+ const struct page *page, struct list_head *to_kill,
+ int force_early)
{
struct vm_area_struct *vma;
struct task_struct *tsk;
@@ -680,7 +682,7 @@ static void collect_procs_file(struct fo
}
#ifdef CONFIG_FS_DAX
-static void add_to_kill_fsdax(struct task_struct *tsk, struct page *p,
+static void add_to_kill_fsdax(struct task_struct *tsk, const struct page *p,
struct vm_area_struct *vma,
struct list_head *to_kill, pgoff_t pgoff)
{
@@ -691,7 +693,7 @@ static void add_to_kill_fsdax(struct tas
/*
* Collect processes when the error hit a fsdax page.
*/
-static void collect_procs_fsdax(struct page *page,
+static void collect_procs_fsdax(const struct page *page,
struct address_space *mapping, pgoff_t pgoff,
struct list_head *to_kill, bool pre_remove)
{
@@ -725,7 +727,7 @@ static void collect_procs_fsdax(struct p
/*
* Collect the processes who have the corrupted page mapped to kill.
*/
-static void collect_procs(struct folio *folio, struct page *page,
+static void collect_procs(const struct folio *folio, const struct page *page,
struct list_head *tokill, int force_early)
{
if (!folio->mapping)
--- a/mm/page_vma_mapped.c~mm-mass-constification-of-folio-page-pointers
+++ a/mm/page_vma_mapped.c
@@ -337,9 +337,10 @@ next_pte:
* outside the VMA or not present, returns -EFAULT.
* Only valid for normal file or anonymous VMAs.
*/
-unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
+unsigned long page_mapped_in_vma(const struct page *page,
+ struct vm_area_struct *vma)
{
- struct folio *folio = page_folio(page);
+ const struct folio *folio = page_folio(page);
struct page_vma_mapped_walk pvmw = {
.pfn = page_to_pfn(page),
.nr_pages = 1,
--- a/mm/rmap.c~mm-mass-constification-of-folio-page-pointers
+++ a/mm/rmap.c
@@ -497,7 +497,7 @@ void __init anon_vma_init(void)
* concurrently without folio lock protection). See folio_lock_anon_vma_read()
* which has already covered that, and comment above remap_pages().
*/
-struct anon_vma *folio_get_anon_vma(struct folio *folio)
+struct anon_vma *folio_get_anon_vma(const struct folio *folio)
{
struct anon_vma *anon_vma = NULL;
unsigned long anon_mapping;
@@ -541,7 +541,7 @@ out:
* reference like with folio_get_anon_vma() and then block on the mutex
* on !rwc->try_lock case.
*/
-struct anon_vma *folio_lock_anon_vma_read(struct folio *folio,
+struct anon_vma *folio_lock_anon_vma_read(const struct folio *folio,
struct rmap_walk_control *rwc)
{
struct anon_vma *anon_vma = NULL;
@@ -1275,8 +1275,9 @@ static void __folio_set_anon(struct foli
* @vma: the vm area in which the mapping is added
* @address: the user virtual address mapped
*/
-static void __page_check_anon_rmap(struct folio *folio, struct page *page,
- struct vm_area_struct *vma, unsigned long address)
+static void __page_check_anon_rmap(const struct folio *folio,
+ const struct page *page, struct vm_area_struct *vma,
+ unsigned long address)
{
/*
* The page's anon-rmap details (mapping and index) are guaranteed to
@@ -2573,7 +2574,7 @@ void __put_anon_vma(struct anon_vma *ano
anon_vma_free(root);
}
-static struct anon_vma *rmap_walk_anon_lock(struct folio *folio,
+static struct anon_vma *rmap_walk_anon_lock(const struct folio *folio,
struct rmap_walk_control *rwc)
{
struct anon_vma *anon_vma;
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
ksm-use-a-folio-in-try_to_merge_one_page.patch
ksm-convert-cmp_and_merge_page-to-use-a-folio.patch
ksm-convert-should_skip_rmap_item-to-take-a-folio.patch
mm-add-pageanonnotksm.patch
mm-add-pageanonnotksm-fix.patch
mm-remove-pageksm.patch
gup-convert-foll_touch-case-in-follow_page_pte-to-folio.patch
mm-convert-page_to_pgoff-to-page_pgoff.patch
mm-use-page_pgoff-in-more-places.patch
mm-renovate-page_address_in_vma.patch
mm-mass-constification-of-folio-page-pointers.patch
bootmem-stop-using-page-index.patch
mm-remove-references-to-page-index-in-huge_memoryc.patch
mm-use-page-private-instead-of-page-index-in-percpu.patch
