nit in sbrk
indirect block
fix dup to share fd struct

mkdir
ls shows stat info for each dir entry

fix acquire() to cli() *before* incrementing nlock
make T_SYSCALL a trap gate, not an interrupt gate
sadly, various crashes if you hold down a keyboard key...

balloc

iget
mkfs makes a file system image
put this in your .bochsrc:
ata0-slave: type=disk, mode=flat, path="fs.img", cylinders=1024, heads=1, spt=1