Re: [PATCH] fuse: skip lookup during atomic_open() when O_CREAT is set

[Jim Harris]

> On Feb 24, 2026, at 8:33 AM, Miklos Szeredi <miklos@xxxxxxxxxx> wrote:
> 
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> 
> 
> On Mon, 23 Feb 2026 at 19:55, Horst Birthelmer <horst@xxxxxxxxxxxxx> wrote:
> 
>> What is wrong with a compound doing LOOKUP + MKNOD + OPEN?
>> If the fuse server knows how to process that 'group' atomically
>> in one big step it will do the right thing,
>> if not, we will call those in series and sort out the data
>> in kernel afterwards.
>> 
>> If we preserve all flags and the real results we can do pretty
>> much exactly the same thing that is done at the moment with just
>> one call to user space.
>> 
>> That was actually what I was experimenting with.
>> 
>> The MKNOD in the middle is optional depending on the O_CREAT flag.
> 
> Okay, I won't stop you experimenting.
> 
> My thinking is that it's simpler as a separate op (dir handle and name
> are the same for LOOKUP and MKNOD).   But adding this special "stop if
> error or non-regular, else skip create if positive" dependency would
> also work.
> 
> Thanks,
> Miklos

Thanks for the feedback everyone. Sounds like compounds will be the way forward to optimize this path, once they are ready.

Do we think compounds will be land for 7.1? Or later?

Best regards,

Jim