include/linux/pagemap.h: introduce attach/detach_page_private

Patch series "Introduce attach/detach_page_private to cleanup code".

This patch (of 10):

The logic in attach_page_buffers and __clear_page_buffers are quite
paired, but

1. they are located in different files.

2. attach_page_buffers is implemented in buffer_head.h, so it could be
   used by other files. But __clear_page_buffers is static function in
   buffer.c and other potential users can't call the function, md-bitmap
   even copied the function.

So, introduce the new attach/detach_page_private to replace them.  With
the new pair of function, we will remove the usage of attach_page_buffers
and __clear_page_buffers in next patches.  Thanks for suggestions about
the function name from Alexander Viro, Andreas Grünbacher, Christoph
Hellwig and Matthew Wilcox.

Suggested-by: Matthew Wilcox <[email protected]>
Signed-off-by: Guoqing Jiang <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: "Darrick J. Wong" <[email protected]>
Cc: William Kucharski <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Andreas Gruenbacher <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Yafang Shao <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Chris Mason <[email protected]>
Cc: Josef Bacik <[email protected]>
Cc: David Sterba <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Jaegeuk Kim <[email protected]>
Cc: Chao Yu <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Anton Altaparmakov <[email protected]>
Cc: Mike Marshall <[email protected]>
Cc: Martin Brandenburg <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Andreas Dilger <[email protected]>
Cc: Chao Yu <[email protected]>
Cc: Dave Chinner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions