Re: [PATCH RFC v2 02/14] md/md-bitmap: pass discard information to bitmap_{start, end}write

[Yu Kuai]

Hi,

在 2025/04/04 17:29, Christoph Hellwig 写道:
> >   	int (*startwrite)(struct mddev *mddev, sector_t offset,
> > -			  unsigned long sectors);
> > +			  unsigned long sectors, bool is_discard);
> >   	void (*endwrite)(struct mddev *mddev, sector_t offset,
> > -			 unsigned long sectors);
> > +			 unsigned long sectors, bool is_discard);
>
> a bool discard is not a very good interface.  I'd expect an op enum or a set
> of flag to properly describe it.

Will update in the next version.

> But is start/end write really the right interface for discard or should it
> have it's own set of ops?

Yes, this is historical issue. The old bitmap handle discard the same as
normal write, while new bitmap handle them differently. And I agree that
add a new ops for discard is better in the long term.

Thanks,
Kuai

> .