[PATCH RFC 20/35] mips: mm: convert __flush_dcache_pages() to __flush_dcache_folio_pages()

David Hildenbrand
2025-08-21T21:33:44Z

Let's make it clearer that we are operating within a single folio by
providing both the folio and the page.

This implies that for flush_dcache_folio() we'll now avoid one more
page->folio lookup, and that we can safely drop the "nth_page" usage.

Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
arch/mips/include/asm/cacheflush.h | 11 +++++++----
arch/mips/mm/cache.c | 8 ++++----
2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/arch/mips/include/asm/cacheflush.h b/arch/mips/include/asm/cacheflush.h
index 1f14132b3fc98..8a2de28936e07 100644
--- a/arch/mips/include/asm/cacheflush.h
+++ b/arch/mips/include/asm/cacheflush.h
@@ -50,13 +50,14 @@ extern void (*flush_cache_mm)(struct mm_struct *mm);
extern void (*flush_cache_range)(struct vm_area_struct *vma,
unsigned long start, unsigned long end);
extern void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page, unsigned long pfn);
-extern void __flush_dcache_pages(struct page *page, unsigned int nr);
+extern void __flush_dcache_folio_pages(struct folio *folio, struct page *page, unsigned int nr);

#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
static inline void flush_dcache_folio(struct folio *folio)
{
if (cpu_has_dc_aliases)
- __flush_dcache_pages(&folio->page, folio_nr_pages(folio));
+ __flush_dcache_folio_pages(folio, folio_page(folio, 0),
+ folio_nr_pages(folio));
else if (!cpu_has_ic_fills_f_dc)
folio_set_dcache_dirty(folio);
}
@@ -64,10 +65,12 @@ static inline void flush_dcache_folio(struct folio *folio)

static inline void flush_dcache_page(struct page *page)
{
+ struct folio *folio = page_folio(page);
+
if (cpu_has_dc_aliases)
- __flush_dcache_pages(page, 1);
+ __flush_dcache_folio_pages(folio, page, folio_nr_pages(folio));
else if (!cpu_has_ic_fills_f_dc)
- folio_set_dcache_dirty(page_folio(page));
+ folio_set_dcache_dirty(folio);
}

#define flush_dcache_mmap_lock(mapping) do { } while (0)
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index bf9a37c60e9f0..e3b4224c9a406 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -99,9 +99,9 @@ SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
return 0;
}

-void __flush_dcache_pages(struct page *page, unsigned int nr)
+void __flush_dcache_folio_pages(struct folio *folio, struct page *page,
+ unsigned int nr)
{
- struct folio *folio = page_folio(page);
struct address_space *mapping = folio_flush_mapping(folio);
unsigned long addr;
unsigned int i;
@@ -117,12 +117,12 @@ void __flush_dcache_pages(struct page *page, unsigned int nr)
* get faulted into the tlb (and thus flushed) anyways.
*/
for (i = 0; i < nr; i++) {
- addr = (unsigned long)kmap_local_page(nth_page(page, i));
+ addr = (unsigned long)kmap_local_page(page + i);
flush_data_cache_page(addr);
kunmap_local((void *)addr);
}
}
-EXPORT_SYMBOL(__flush_dcache_pages);
+EXPORT_SYMBOL(__flush_dcache_folio_pages);

void __flush_anon_page(struct page *page, unsigned long vmaddr)
{
--
2.50.1