Re: [PATCH v3 09/13] device core: Introduce multiple dma pfn offsets

From: Dan Carpenter <dan.carpenter@oracle.com>
To: Jim Quinlan <james.quinlan@broadcom.com>
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Subject: Re: [PATCH v3 09/13] device core: Introduce multiple dma pfn offsets
Date: Thu, 4 Jun 2020 17:18:57 +0300	[thread overview]
Message-ID: <20200604141857.GH22511@kadam> (raw)
In-Reply-To: <CA+-6iNyaL8izv5eHJyYkhwu9diPsqT0AD08UU_ECexNcdrT+jA@mail.gmail.com>

On Thu, Jun 04, 2020 at 09:48:49AM -0400, Jim Quinlan wrote:
> > > +     r = devm_kcalloc(dev, 1, sizeof(struct dma_pfn_offset_region),
> > > +                      GFP_KERNEL);
> >
> > Use:    r = devm_kzalloc(dev, sizeof(*r), GFP_KERNEL);
> Will fix.
> 
> >
> >
> > > +     if (!r)
> > > +             return -ENOMEM;
> > > +
> > > +     r->uniform_offset = true;
> > > +     r->pfn_offset = pfn_offset;
> > > +
> > > +     return 0;
> > > +}
> >
> > This function doesn't seem to do anything useful.  Is part of it
> > missing?
> No, the uniform pfn offset is a special case.

Sorry, I wasn't clear.  We're talking about different things.  The code
does:

	r = devm_kzalloc(dev, sizeof(*r), GFP_KERNEL);
	if (!r)
		return -ENOMEM;

	r->uniform_offset = true;
	r->pfn_offset = pfn_offset;

	return 0;

The code allocates "r" and then doesn't save it anywhere so there is
no point.

regards,
dan carpenter

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