Re: [PATCH] block: refactor duplicated macros

[Matteo Croce]

On Wed, Mar 4, 2020 at 9:57 PM Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
>
> On Sun, Feb 23, 2020 at 9:04 AM Matteo Croce <mcroce@xxxxxxxxxx> wrote:
> >
> > The macros PAGE_SECTORS, PAGE_SECTORS_SHIFT and SECTOR_MASK are defined
> > several times in different flavours across the whole tree.
> > Define them just once in a common header.
> >
> > Signed-off-by: Matteo Croce <mcroce@xxxxxxxxxx>
> > ---
> >  block/blk-lib.c                  |  2 +-
> >  drivers/block/brd.c              |  3 ---
> >  drivers/block/null_blk_main.c    |  4 ----
> >  drivers/block/zram/zram_drv.c    |  8 ++++----
> >  drivers/block/zram/zram_drv.h    |  2 --
> >  drivers/dax/super.c              |  2 +-
>
> For the dax change:
>
> Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
>
> However...
>
> [..]
> >  include/linux/blkdev.h           |  4 ++++
> [..]
> > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> > index 053ea4b51988..b3c9be6906a0 100644
> > --- a/include/linux/blkdev.h
> > +++ b/include/linux/blkdev.h
> > @@ -910,6 +910,10 @@ static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
> >  #define SECTOR_SIZE (1 << SECTOR_SHIFT)
> >  #endif
> >
> > +#define PAGE_SECTORS_SHIFT     (PAGE_SHIFT - SECTOR_SHIFT)
> > +#define PAGE_SECTORS           (1 << PAGE_SECTORS_SHIFT)
> > +#define SECTOR_MASK            (PAGE_SECTORS - 1)
> > +
>
> ...I think SECTOR_MASK is misnamed given it considers pages, and
> should probably match the polarity of PAGE_MASK, i.e.
>
> #define PAGE_SECTORS_MASK            (~(PAGE_SECTORS - 1))
>

Makes sense. I just kept the same value as in drivers/block/null_blk_main.c

-- 
Matteo Croce
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