Re: [PATCH RFC v4 00/15] fuse: fuse-over-io-uring

[Bernd Schubert <bschubert@ddn.com>]

Hi David,

On 10/23/24 00:10, David Wei wrote:
> [You don't often get email from dw@davidwei.uk. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> On 2024-10-15 17:05, Bernd Schubert wrote:
>> RFCv1 and RFCv2 have been tested with multiple xfstest runs in a VM
>> (32 cores) with a kernel that has several debug options
>> enabled (like KASAN and MSAN). RFCv3 is not that well tested yet.
>> O_DIRECT is currently not working well with /dev/fuse and
>> also these patches, a patch has been submitted to fix that (although
>> the approach is refused)
>> https://www.spinics.net/lists/linux-fsdevel/msg280028.html
> 
> Hi Bernd, I applied this patch and the associated libfuse patch at:
> 
> https://github.com/bsbernd/libfuse/tree/aligned-writes
> 
> I have a simple Python FUSE client that is still returning EINVAL for
> write():
> 
> with open(sys.argv[1], 'r+b') as f:
>     mmapped_file = mmap.mmap(f.fileno(), 0)
>     shm = shared_memory.SharedMemory(create=True, size=mmapped_file.size())
>     shm.buf[:mmapped_file.size()] = mmapped_file[:]
>     fd = os.open("/home/vmuser/scratch/dest/out", O_RDWR|O_CREAT|O_DIRECT)
>     with open(fd, 'w+b') as f2:
>         f2.write(bytes(shm.buf))
>     mmapped_file.close()
>     shm.unlink()
>     shm.close()
> 
> I'll keep looking at this but letting you know in case it's something
> obvious again.

the 'aligned-writes' libfuse branch would need another kernel patch. Please
hold on a little bit, I hope to send out a new version later today or
tomorrow that separates headers from payload - alignment is guaranteed. 


Thanks,
Bernd