[PATCH 46/71] kernfs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
From: Kirill A. Shutemov
Date: Sun Mar 20 2016 - 14:57:45 EST
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: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/kernfs/mount.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c
index 8eaf417187f1..43393e1008d1 100644
--- a/fs/kernfs/mount.c
+++ b/fs/kernfs/mount.c
@@ -69,8 +69,8 @@ static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
struct dentry *root;
info->sb = sb;
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+ sb->s_blocksize = PAGE_SIZE;
+ sb->s_blocksize_bits = PAGE_SHIFT;
sb->s_magic = magic;
sb->s_op = &kernfs_sops;
sb->s_time_gran = 1;
--
2.7.0