mm: make page_mapped() take a const argument

None of the functions called by page_mapped() modify the page or folio, so
mark them all as const.

Link: https://lkml.kernel.org/r/20240326171045.410737-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2024-03-26 17:10:28 +00:00 committed by Andrew Morton
parent 2ace5a670e
commit b84fd2835c
3 changed files with 11 additions and 10 deletions

View File

@ -1200,7 +1200,7 @@ static inline int is_vmalloc_or_module_addr(const void *x)
* debugging purposes - it does not include PTE-mapped sub-pages; look
* at folio_mapcount() or page_mapcount() instead.
*/
static inline int folio_entire_mapcount(struct folio *folio)
static inline int folio_entire_mapcount(const struct folio *folio)
{
VM_BUG_ON_FOLIO(!folio_test_large(folio), folio);
return atomic_read(&folio->_entire_mapcount) + 1;
@ -1240,7 +1240,7 @@ static inline int page_mapcount(struct page *page)
return mapcount;
}
int folio_total_mapcount(struct folio *folio);
int folio_total_mapcount(const struct folio *folio);
/**
* folio_mapcount() - Calculate the number of mappings of this folio.
@ -1253,14 +1253,14 @@ int folio_total_mapcount(struct folio *folio);
*
* Return: The number of times this folio is mapped.
*/
static inline int folio_mapcount(struct folio *folio)
static inline int folio_mapcount(const struct folio *folio)
{
if (likely(!folio_test_large(folio)))
return atomic_read(&folio->_mapcount) + 1;
return folio_total_mapcount(folio);
}
static inline bool folio_large_is_mapped(struct folio *folio)
static inline bool folio_large_is_mapped(const struct folio *folio)
{
/*
* Reading _entire_mapcount below could be omitted if hugetlb
@ -1288,7 +1288,7 @@ static inline bool folio_mapped(struct folio *folio)
* For compound page it returns true if any sub-page of compound page is mapped,
* even if this particular sub-page is not itself mapped by any PTE or PMD.
*/
static inline bool page_mapped(struct page *page)
static inline bool page_mapped(const struct page *page)
{
if (likely(!PageCompound(page)))
return atomic_read(&page->_mapcount) >= 0;
@ -2070,7 +2070,7 @@ static inline void set_page_links(struct page *page, enum zone_type zone,
*
* Return: A positive power of two.
*/
static inline long folio_nr_pages(struct folio *folio)
static inline long folio_nr_pages(const struct folio *folio)
{
if (!folio_test_large(folio))
return 1;

View File

@ -71,7 +71,7 @@ void page_writeback_init(void);
* How many individual pages have an elevated _mapcount. Excludes
* the folio's entire_mapcount.
*/
static inline int folio_nr_pages_mapped(struct folio *folio)
static inline int folio_nr_pages_mapped(const struct folio *folio)
{
return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED;
}
@ -81,7 +81,8 @@ static inline int folio_nr_pages_mapped(struct folio *folio)
* folio. We cannot rely on folio->swap as there is no guarantee that it has
* been initialized. Used for calling arch_swap_restore()
*/
static inline swp_entry_t folio_swap(swp_entry_t entry, struct folio *folio)
static inline swp_entry_t folio_swap(swp_entry_t entry,
const struct folio *folio)
{
swp_entry_t swap = {
.val = ALIGN_DOWN(entry.val, folio_nr_pages(folio)),
@ -90,7 +91,7 @@ static inline swp_entry_t folio_swap(swp_entry_t entry, struct folio *folio)
return swap;
}
static inline void *folio_raw_mapping(struct folio *folio)
static inline void *folio_raw_mapping(const struct folio *folio)
{
unsigned long mapping = (unsigned long)folio->mapping;

View File

@ -1134,7 +1134,7 @@ int pfn_mkclean_range(unsigned long pfn, unsigned long nr_pages, pgoff_t pgoff,
return page_vma_mkclean_one(&pvmw);
}
int folio_total_mapcount(struct folio *folio)
int folio_total_mapcount(const struct folio *folio)
{
int mapcount = folio_entire_mapcount(folio);
int nr_pages;