[$] Bringing bcachefs to the mainline

Bcachefs is a longstanding out-of-tree
filesystem that grew out of the bcache caching
layer that has been in the kernel for nearly ten years. Based on a
session led by Kent Overstreet at the
2022 Linux Storage,
Filesystem, Memory-management and BPF Summit (LSFMM), though, it would
seem that bcachefs is likely to be heading upstream soon. He intends to
start the process toward mainline inclusion over the next six months or so.