[$] Buffer sizes for FUSE io_uring

The Filesystem inUserspace (FUSE) subsystem provides a way to service filesystemrequests from a user-space server, which moves the format-handling code outof the kernel. The FUSE server can use the io_uringfacility for better performance, but Bernd Schubert is concerned thatmemory is being wasted because the current implementation has a single,large buffer size that is excessive for small I/O operations. He led a discussion on that topicin the filesystem track of the 2026 Linux Storage,Filesystem, Memory Management, and BPF Summit in Zagreb, Croatia.