linux-kernel - Re: [PATCH RFC v2 0/2] fuse: compound commands

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Message-ID: <cc37fe4a-8e03-41c7-bec5-00e946928feb@linux.alibaba.com>
Date: Tue, 30 Dec 2025 19:58:06 +0800
From: Jingbo Xu <jefflexu@...ux.alibaba.com>
To: Horst Birthelmer <horst@...thelmer.de>
Cc: Horst Birthelmer <hbirthelmer@...glemail.com>,
 Miklos Szeredi <miklos@...redi.hu>, Bernd Schubert <bschubert@....com>,
 linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
 Horst Birthelmer <hbirthelmer@....com>, syzbot@...kaller.appspotmail.com
Subject: Re: [PATCH RFC v2 0/2] fuse: compound commands



On 12/30/25 4:36 PM, Horst Birthelmer wrote:
> On Mon, Dec 29, 2025 at 02:03:02PM +0800, Jingbo Xu wrote:
>> Hi Horst & Bernd,
>>
>> On 12/24/25 6:13 AM, Horst Birthelmer wrote:
>>> In the discussion about open+getattr here [1] Bernd and Miklos talked
>>> about the need for a compound command in fuse that could send multiple
>>> commands to a fuse server.
>>>     
>>> Here's a propsal for exactly that compound command with an example
>>> (the mentioned open+getattr).
>>>     
>>> [1] https://lore.kernel.org/linux-fsdevel/CAJfpegshcrjXJ0USZ8RRdBy=e0MxmBTJSCE0xnxG8LXgXy-xuQ@mail.gmail.com/
>>>
>>
>> To achieve close-to-open, why not just invalidate the cached attr on
>> open so that the following access to the attr would trigger a new
>> FUSE_GETATTR request to fetch the latest attr from server?
>>
> 
> Hi Jingbo,
> 
> you are probably right, that it can be achieved that way. I thas some consequences that can be avoided, like having to wait at a later moment for the attributes to be fetched.
> 
> The main goal of this patch however was not close-to-open, even though it was discussed in that context.
> 
> We can do a lot more with the compounds than just fix close-to-open consistency. As Bernd mentioned, I am very close to havin implemented the fuse_atomic_open() call with compounds, namely the atomic combination of lookup+create.
> And there are some more ideas out there.
> 
> open+getattr was just the low hanging fruit in this case.


Got it. Thanks.

-- 
Thanks,
Jingbo