Received-SPF: pass (google.com: domain of linux-kernel+bounces-79903-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Message-ID: <121d0ce8-e542-4a1c-85e9-0d1863f36741@infradead.org>
Date: Sat, 24 Feb 2024 15:40:11 -0800
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [RFC PATCH 07/20] famfs: Add include/linux/famfs_ioctl.h
Content-Language: en-US
To: John Groves <John@groves.net>
Cc: John Groves <jgroves@micron.com>, Jonathan Corbet <corbet@lwn.net>,
 Dan Williams <dan.j.williams@intel.com>,
 Vishal Verma <vishal.l.verma@intel.com>, Dave Jiang <dave.jiang@intel.com>,
 Alexander Viro <viro@zeniv.linux.org.uk>,
 Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
 Matthew Wilcox <willy@infradead.org>, linux-cxl@vger.kernel.org,
 linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org,
 linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev, john@jagalactic.com,
 Dave Chinner <david@fromorbit.com>, Christoph Hellwig <hch@infradead.org>,
 dave.hansen@linux.intel.com, gregory.price@memverge.com
References: <cover.1708709155.git.john@groves.net>
 <b40ca30e4bf689249a8c237909d9a7aaca9861e4.1708709155.git.john@groves.net>
 <8f62b688-6c14-4eab-b039-7d9a112893f8@infradead.org>
 <7onhdq4spd7mnkr5c443sbvnr7l4n34amtterg4soiey2qubyl@r2ppa6fsohnk>
 <97cde8f6-21ed-45b9-9618-568933102f05@infradead.org>
 <7rkmolss5vkdljnh6uksfkepklwofe3bkdsf36qhokyltjoxlx@xqgef734pidg>
From: Randy Dunlap <rdunlap@infradead.org>
In-Reply-To: <7rkmolss5vkdljnh6uksfkepklwofe3bkdsf36qhokyltjoxlx@xqgef734pidg>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit


On 2/24/24 15:32, John Groves wrote:
> On 24/02/23 07:27PM, Randy Dunlap wrote:
>> Hi John,
>>
>> On 2/23/24 18:23, John Groves wrote:
>>>>> +
>>>>> +#define FAMFSIOC_MAGIC 'u'
>>>> This 'u' value should be documented in
>>>> Documentation/userspace-api/ioctl/ioctl-number.rst.
>>>>
>>>> and if possible, you might want to use values like 0x5x or 0x8x
>>>> that don't conflict with the ioctl numbers that are already used
>>>> in the 'u' space.
>>> Will do. I was trying to be too clever there, invoking "mu" for
>>> micron. 
>>
>> I might have been unclear about this one.
>> It's OK to use 'u' but the values 1-4 below conflict in the 'u' space:
>>
>> 'u'   00-1F  linux/smb_fs.h                                          gone
>> 'u'   20-3F  linux/uvcvideo.h                                        USB video class host driver
>> 'u'   40-4f  linux/udmabuf.h
>>
>> so if you could use
>> 'u'   50-5f
>> or
>> 'u'   80-8f
>>
>> then those conflicts wouldn't be there.
>> HTH.
>>
>>>>> +
>>>>> +/* famfs file ioctl opcodes */
>>>>> +#define FAMFSIOC_MAP_CREATE    _IOW(FAMFSIOC_MAGIC, 1, struct famfs_ioc_map)
>>>>> +#define FAMFSIOC_MAP_GET       _IOR(FAMFSIOC_MAGIC, 2, struct famfs_ioc_map)
>>>>> +#define FAMFSIOC_MAP_GETEXT    _IOR(FAMFSIOC_MAGIC, 3, struct famfs_extent)
>>>>> +#define FAMFSIOC_NOP           _IO(FAMFSIOC_MAGIC,  4)
>>
>> -- 
>> #Randy
> 
> Thanks Randy; I think I'm the one that didn't read carefully enough.
> 
> Does this look right?
> 
> diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
> index 457e16f06e04..44a44809657b 100644
> --- a/Documentation/userspace-api/ioctl/ioctl-number.rst
> +++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
> @@ -288,6 +288,7 @@ Code  Seq#    Include File                                           Comments
>  'u'   00-1F  linux/smb_fs.h                                          gone
>  'u'   20-3F  linux/uvcvideo.h                                        USB video class host driver
>  'u'   40-4f  linux/udmabuf.h                                         userspace dma-buf misc device
> +'u'   50-5F  linux/famfs_ioctl.h                                     famfs shared memory file system
>  'v'   00-1F  linux/ext2_fs.h                                         conflict!
>  'v'   00-1F  linux/fs.h                                              conflict!
>  'v'   00-0F  linux/sonypi.h                                          conflict!
> diff --git a/include/uapi/linux/famfs_ioctl.h b/include/uapi/linux/famfs_ioctl.h
> index 6b3e6452d02f..57521898ed57 100644
> --- a/include/uapi/linux/famfs_ioctl.h
> +++ b/include/uapi/linux/famfs_ioctl.h
> @@ -48,9 +48,9 @@ struct famfs_ioc_map {
>  #define FAMFSIOC_MAGIC 'u'
> 
>  /* famfs file ioctl opcodes */
> -#define FAMFSIOC_MAP_CREATE    _IOW(FAMFSIOC_MAGIC, 1, struct famfs_ioc_map)
> -#define FAMFSIOC_MAP_GET       _IOR(FAMFSIOC_MAGIC, 2, struct famfs_ioc_map)
> -#define FAMFSIOC_MAP_GETEXT    _IOR(FAMFSIOC_MAGIC, 3, struct famfs_extent)
> -#define FAMFSIOC_NOP           _IO(FAMFSIOC_MAGIC,  4)
> +#define FAMFSIOC_MAP_CREATE    _IOW(FAMFSIOC_MAGIC, 0x50, struct famfs_ioc_map)
> +#define FAMFSIOC_MAP_GET       _IOR(FAMFSIOC_MAGIC, 0x51, struct famfs_ioc_map)
> +#define FAMFSIOC_MAP_GETEXT    _IOR(FAMFSIOC_MAGIC, 0x52, struct famfs_extent)
> +#define FAMFSIOC_NOP           _IO(FAMFSIOC_MAGIC,  0x53)
> 
> Thank you!
> John
> 

Yes, that looks good.
Thanks.

-- 
#Randy