[03/71] parisc: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

Commit Message

Kirill A . Shutemov March 20, 2016, 6:40 p.m. UTC

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 <[e-mail]>
Cc: "James E.J. Bottomley" <[e-mail]>
Cc: Helge Deller <[e-mail]>
---
 arch/parisc/kernel/cache.c | 2 +-
 arch/parisc/mm/init.c      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

Patch

diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 91c2a39cd5aa..67001277256c 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -319,7 +319,7 @@  void flush_dcache_page(struct page *page)
 	if (!mapping)
 		return;
 
-	pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff = page->index;
 
 	/* We have carefully arranged in arch_get_unmapped_area() that
 	 * *any* mappings of a file are always congruently mapped (whether
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 3c07d6b96877..6b3e7c6ee096 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -22,7 +22,7 @@ 
 #include <linux/swap.h>
 #include <linux/unistd.h>
 #include <linux/nodemask.h>	/* for node_online_map */
-#include <linux/pagemap.h>	/* for release_pages and page_cache_release */
+#include <linux/pagemap.h>	/* for release_pages */
 #include <linux/compat.h>
 
 #include <asm/pgalloc.h>