Re: [PATCH] Fuse: Add backing file support for uring_cmd

[Moinak Bhattacharyya <moinakb001@gmail.com>]

I don't have the modifications to libfuse. What tree are you using for 
the uring modifications? I dont see any uring patches on the latest 
master liburing.
>> It is possible, for example set FOPEN_PASSTHROUGH_FD to
>> interpret backing_id as backing_fd, but note that in the current
>> implementation of passthrough_hp, not every open does
>> fuse_passthrough_open().
>> The non-first open of an inode uses a backing_id stashed in inode,
>> from the first open so we'd need different server logic depending on
>> the commands channel, which is not nice.
I wonder if we can just require URING registered FDs (using 
IORING_REGISTER_FILES). I think io_uring does checks on the file 
permissions when the FD is registered.