RE: [EXT] Re: [PATCH v2 1/2] block: decouple secure erase size limit from discard size limit

[Luke Wang]

> -----Original Message-----
> From: Christoph Hellwig <hch@xxxxxxxxxxxxx>
> Sent: Monday, December 15, 2025 11:43 PM
> To: Luke Wang <ziniu.wang_1@xxxxxxx>
> Cc: axboe@xxxxxxxxx; ulf.hansson@xxxxxxxxxx; linux-block@xxxxxxxxxxxxxxx;
> linux-mmc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; imx@xxxxxxxxxxxxxxx
> Subject: [EXT] Re: [PATCH v2 1/2] block: decouple secure erase size limit from
> discard size limit
> 
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> 
> > --- a/block/blk-merge.c
> > +++ b/block/blk-merge.c
> > @@ -169,8 +169,13 @@ struct bio *bio_split_discard(struct bio *bio, const
> struct queue_limits *lim,
> >
> >       granularity = max(lim->discard_granularity >> 9, 1U);
> >
> > -     max_discard_sectors =
> > -             min(lim->max_discard_sectors, bio_allowed_max_sectors(lim));
> > +     if (bio_op(bio) == REQ_OP_SECURE_ERASE)
> > +             max_discard_sectors = min(lim->max_secure_erase_sectors,
> > +                                       bio_allowed_max_sectors(lim));
> > +     else
> > +             max_discard_sectors = min(lim->max_discard_sectors,
> > +                                       bio_allowed_max_sectors(lim));
> 
> Please factor our a low-level helper and pass the max_sectors
> as argument.

I'm not sure I get your point. Do you mean helper function like get_max_io_size()? 
Or do you mean something different?  Please explain in more detail.

Thanks,
Luke