On Sun 20-03-16 21:40:39, Kirill A. Shutemov wrote:
> 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: Jan Kara <jack@xxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>