I played a ton with the Linux file system while I was in college, and it's filled with code that is obviously a result tech debt. For that reason, it's one of the more complex parts of the kernel.

This is awesome, but I don't see the `buffer_head` getting replaced anytime soon. It's so baked into existing filesystems, I can't see it going away for at least half a decade.

Also, love lwn.net—great find!