From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Baoquan He <bhe@redhat.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"hch@infradead.org" <hch@infradead.org>,
"agordeev@linux.ibm.com" <agordeev@linux.ibm.com>,
"wangkefeng.wang@huawei.com" <wangkefeng.wang@huawei.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v2 01/11] mm/ioremap: change the return value of io[re|un]map_allowed and rename
Date: Tue, 23 Aug 2022 15:26:07 +0000 [thread overview]
Message-ID: <429cb367-923f-bb3d-ccf0-57dce0c7f35b@csgroup.eu> (raw)
In-Reply-To: <YwTu1kzcIUxsTL4j@MiWiFi-R3L-srv>
Le 23/08/2022 à 17:14, Baoquan He a écrit :
> On 08/23/22 at 05:24am, Christophe Leroy wrote:
>>
>>
>> Le 23/08/2022 à 02:20, Baoquan He a écrit :
>>> On 08/22/22 at 06:25am, Christophe Leroy wrote:
>>>>
>>>>
>>>> Le 20/08/2022 à 02:31, Baoquan He a écrit :
>>>>> In some architectures, there are ARCH specifici io address mapping
>>>>> handling when calling ioremap() or ioremap_prot(), e.g, arc, ia64,
>>>>> openrisc, s390, sh.
>>>>>
>>>>> In oder to convert them to take GENERIC_IOREMAP method, we need change
>>>>> the return value of hook ioremap_allowed() and iounmap_allowed().
>>>>> Meanwhile, rename them to arch_ioremap() and arch_iounmap() to reflect
>>>>> their current behaviour.
>>>
>>> Thanks for reviewing.
>>>
>>>>
>>>> Please don't just say you need to change the return value. Explain why.
>>>
>>> The 1st paragraph and the sentence 'In oder to convert them to take
>>> GENERIC_IOREMAP method' tell the reason, no?
>>
>> What I would like to read is _why_ you need to change the return value
>> in order to convert to GENERIC_IOREMAP
>
> I rephrase the log as below, it's OK to you? Or please help check and
> tell what I need to improve to better explain the reason.
>
> ====
> The current io[re|un]map_allowed() hooks are used to check if the
> io[re|un]map() actions are qualified to proceed when taking
> GENERIC_IOREMAP way to do ioremap()/iounmap(). Otherwise io[re|un]map()
> will return NULL.
>
> On some architectures like arc, ia64, openris, s390, sh, there are
> ARCH specific io address mapping to translate the passed in physical
> address to io address when calling ioremap(). In order to convert
> these architectures to take GENERIC_IOREMAP way to ioremap(), we need
> change the return value of hook ioremap_allowed() and iounmap_allowed().
> With the change, we can move the architecture specific io address
> mapping into ioremap_allowed() hook, and give the mapped io address
> out to let ioremap_prot() return it. While at it, rename the hooks to
> arch_ioremap() and arch_iounmap() to reflect their new behaviour.
> ====
>
That looks more in line with the type of explanation I foresee in the
commit message, thanks.
Christophe
next prev parent reply other threads:[~2022-08-23 17:39 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-20 0:31 [PATCH v2 00/11] mm: ioremap: Convert architectures to take GENERIC_IOREMAP way Baoquan He
2022-08-20 0:31 ` [PATCH v2 01/11] mm/ioremap: change the return value of io[re|un]map_allowed and rename Baoquan He
2022-08-21 6:53 ` Christoph Hellwig
2022-08-22 23:55 ` Baoquan He
2022-08-22 6:25 ` Christophe Leroy
2022-08-23 0:20 ` Baoquan He
2022-08-23 5:24 ` Christophe Leroy
2022-08-23 15:14 ` Baoquan He
2022-08-23 15:26 ` Christophe Leroy [this message]
2022-08-24 8:16 ` David Laight
2022-08-28 14:44 ` Baoquan He
2022-08-28 8:36 ` Alexander Gordeev
2022-08-28 9:55 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 02/11] mm: ioremap: fixup the physical address and page prot Baoquan He
2022-08-21 6:54 ` Christoph Hellwig
2022-08-23 1:13 ` Baoquan He
2022-08-22 6:30 ` Christophe Leroy
2022-08-23 1:19 ` Baoquan He
2022-08-23 5:33 ` Christophe Leroy
2022-08-23 12:32 ` Baoquan He
2022-08-23 19:03 ` Christophe Leroy
2022-08-28 11:10 ` Baoquan He
2022-09-12 2:55 ` Baoquan He
2022-09-12 7:10 ` Christophe Leroy
2022-09-13 15:11 ` Baoquan He
2022-09-21 16:40 ` Christophe Leroy
2022-09-22 13:23 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 03/11] mm: ioremap: allow ARCH to have its own ioremap definition Baoquan He
2022-08-21 6:57 ` Christoph Hellwig
2022-08-23 2:42 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 04/11] arc: mm: Convert to GENERIC_IOREMAP Baoquan He
2022-08-20 0:31 ` [PATCH v2 05/11] hexagon: " Baoquan He
2022-08-20 1:23 ` Brian Cain
2022-08-21 7:00 ` Christoph Hellwig
2022-08-28 15:08 ` Baoquan He
2022-08-22 6:38 ` Christophe Leroy
2022-08-28 15:12 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 06/11] ia64: " Baoquan He
2022-08-21 7:02 ` Christoph Hellwig
2022-08-28 15:12 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 07/11] openrisc: " Baoquan He
2022-08-21 7:03 ` Christoph Hellwig
2022-08-29 1:40 ` Baoquan He
2022-08-29 6:42 ` Stafford Horne
2022-08-29 8:18 ` Baoquan He
2022-08-30 6:05 ` Christophe Leroy
2022-08-29 6:32 ` Stafford Horne
2022-08-29 8:19 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 08/11] parisc: " Baoquan He
2022-08-20 4:03 ` kernel test robot
2022-08-21 10:26 ` Baoquan He
2022-08-21 14:18 ` Helge Deller
2022-08-30 13:00 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 09/11] s390: " Baoquan He
2022-08-21 7:05 ` Christoph Hellwig
2022-08-22 15:08 ` Niklas Schnelle
2022-08-31 8:59 ` Baoquan He
2022-08-22 15:19 ` Niklas Schnelle
2022-08-31 8:58 ` Baoquan He
2022-08-23 12:30 ` Niklas Schnelle
2022-08-31 8:50 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 10/11] sh: " Baoquan He
2022-08-20 3:41 ` kernel test robot
2022-09-01 10:39 ` Baoquan He
2022-09-01 12:11 ` [kbuild-all] " Chen, Rong A
2022-09-01 12:31 ` Baoquan He
2022-09-02 9:48 ` Baoquan He
2022-08-21 7:06 ` Christoph Hellwig
2022-09-01 7:36 ` Baoquan He
2022-08-20 0:31 ` [PATCH v2 11/11] xtensa: " Baoquan He
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=429cb367-923f-bb3d-ccf0-57dce0c7f35b@csgroup.eu \
--to=christophe.leroy@csgroup.eu \
--cc=agordeev@linux.ibm.com \
--cc=akpm@linux-foundation.org \
--cc=bhe@redhat.com \
--cc=hch@infradead.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=wangkefeng.wang@huawei.com \
/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).