linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>,
	Kefeng Wang <wangkefeng.wang@huawei.com>,
	 Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	 Linux ARM <linux-arm-kernel@lists.infradead.org>,
	 Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux-MM <linux-mm@kvack.org>
Subject: Re: [PATCH 2/4] mm: ioremap: Add arch_ioremap/iounmap_check()
Date: Wed, 27 Apr 2022 22:46:05 +0200	[thread overview]
Message-ID: <CAK8P3a2BJA6KCJuyJOcy640=rTXfL7VEP8uFdLQH+2FRftFMfg@mail.gmail.com> (raw)
In-Reply-To: <20220427112545.3b8b9c46e5e5731b02394ace@linux-foundation.org>

On Wed, Apr 27, 2022 at 8:25 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> On Wed, 27 Apr 2022 20:20:30 +0200 Arnd Bergmann <arnd@arndb.de> wrote:
> > On Wed, Apr 27, 2022 at 2:14 PM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> > >
> > > +bool __weak arch_ioremap_check(phys_addr_t addr, size_t size, unsigned long prot)
> > > +{
> > > +       return true;
> > > +}
> > > +
> > > +bool __weak arch_iounmap_check(void __iomem *addr)
> > > +{
> > > +       return true;
> > > +}
> > > +
> >
> > I don't really like the weak functions.
>
> How come?  They work quite nicely here?

I find them rather confusing, mostly because it is less clear whether the
fallback function is used in a given configuration, or a replacement one is
present.

This is a bigger problem in some subsystems than others, and the main
place I don't like is the drivers/pci/ subsystem. A number of the uses
there should be driver specific but happen to be implemented by
architectures instead. Maybe I'm just projecting that onto other uses,
but I definitely have a bad feeling about them here.

       Arnd

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2022-04-27 20:47 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-27 12:14 [PATCH 0/4] arm64: Cleanup ioremap() and support ioremap_prot() Kefeng Wang
2022-04-27 12:14 ` [PATCH 1/4] mm: ioremap: Setup phys_addr of struct vm_struct Kefeng Wang
2022-04-27 17:10   ` Andrew Morton
2022-04-28  1:40     ` Kefeng Wang
2022-04-28 15:41   ` Christoph Hellwig
2022-04-27 12:14 ` [PATCH 2/4] mm: ioremap: Add arch_ioremap/iounmap_check() Kefeng Wang
2022-04-27 17:04   ` Andrew Morton
2022-04-28  6:16     ` Kefeng Wang
2022-04-28 15:46       ` Christoph Hellwig
2022-04-27 18:20   ` Arnd Bergmann
2022-04-27 18:25     ` Andrew Morton
2022-04-27 20:46       ` Arnd Bergmann [this message]
2022-04-28  6:20     ` Kefeng Wang
2022-04-28  6:47       ` Arnd Bergmann
2022-04-27 12:14 ` [PATCH 3/4] arm64: mm: Convert to GENERIC_IOREMAP Kefeng Wang
2022-04-27 17:11   ` Andrew Morton
2022-04-27 12:14 ` [PATCH 4/4] arm64: Add HAVE_IOREMAP_PROT support Kefeng Wang
2022-04-28 10:46 ` [PATCH 0/4] arm64: Cleanup ioremap() and support ioremap_prot() Will Deacon
2022-04-28 11:48   ` Kefeng Wang
2022-04-28 15:48   ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CAK8P3a2BJA6KCJuyJOcy640=rTXfL7VEP8uFdLQH+2FRftFMfg@mail.gmail.com' \
    --to=arnd@arndb.de \
    --cc=akpm@linux-foundation.org \
    --cc=catalin.marinas@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=wangkefeng.wang@huawei.com \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).