[$] Using dma-bufs for read and write operations

The kernel's dma-bufsubsystem provides a way for drivers to share memory buffers, usuallyin order to support efficient device-to-device I/O. At the 2026 Linux Storage,Filesystem, Memory Management, and BPF Summit, Pavel Begunkov, assistedby Kanchan Joshi, led a joint session of the storage and memory-managementtracks to explore ways to make the use of dma-bufs more efficient yet, andto make them available for read and write operations initiated by userspace.