PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago
with promise that one day it will be possible to implement page cache with
bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_*
or PAGE_* constant should be used in a particular case, especially on the
border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
---
arch/arm/mm/flush.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index d0ba3551d49a..3cced8455727 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -235,7 +235,7 @@ void __flush_dcache_page(struct address_space *mapping, struct page *page)
*/
if (mapping && cache_is_vipt_aliasing())
flush_pfn_alias(page_to_pfn(page),
- page->index << PAGE_CACHE_SHIFT);
+ page->index << PAGE_SHIFT);
}
static void __flush_dcache_aliases(struct address_space *mapping, struct page *page)
@@ -250,7 +250,7 @@ static void __flush_dcache_aliases(struct address_space *mapping, struct page *p
* data in the current VM view associated with this page.
* - aliasing VIPT: we only need to find one mapping of this page.
*/
- pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+ pgoff = page->index;
flush_dcache_mmap_lock(mapping);
vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
--
2.7.0
--
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