diff mbox

[26/71] configfs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

Message ID 1458499278-1516-27-git-send-email-kirill.shutemov@linux.intel.com (mailing list archive)
State New, archived
Headers show

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 <kirill.shutemov@linux.intel.com>
Cc: Joel Becker <jlbec@evilplan.org
Cc: Christoph Hellwig <hch@lst.de>
---
 fs/configfs/mount.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Christoph Hellwig March 21, 2016, 2:32 p.m. UTC | #1
Can I don't think sending out per-subsystem patchlets for this global
change is very useful.  That beeing said I support getting rid of 
PAGE_CACHE_SIZE!
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diff mbox

Patch

diff --git a/fs/configfs/mount.c b/fs/configfs/mount.c
index a8f3b589a2df..cfd91320e869 100644
--- a/fs/configfs/mount.c
+++ b/fs/configfs/mount.c
@@ -71,8 +71,8 @@  static int configfs_fill_super(struct super_block *sb, void *data, int silent)
 	struct inode *inode;
 	struct dentry *root;
 
-	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 = CONFIGFS_MAGIC;
 	sb->s_op = &configfs_ops;
 	sb->s_time_gran = 1;