relix: xv6 work continued from the MIT PDOS team

xv6 was a re-implementation of Dennis Ritchie's and Ken Thompson's Unix Version 6 (v6) for the i386 processor.

Enchancements from the original XV6:

• pixel graphics support with custom fonts
• fixed broken SMP due to a QEMU regression
• added users, groups, and permissions
• organized files into /etc, /bin, and /dev
• ACPI support
• POSIX alignment and support
• improved and added coreutils
• organized file structure support; kernel and userland has a clear separation.
• syscall fuzzing (in the works)
• Rust language support (look in kernel/rust/ and userspace/rust)
• doubly indirect block pointer inodes (max filesize 1MiB -> 512MiB)
• 64-bit port, code pulled from swetland/xv6
• multiboot2 support
• SATA R/W support
• pwd.h and /etc/passwd

# dependencies - gcc/clang - ld/lld - objdump, objcopy, ar, ranlib - rustc, cargo (nightly) - qemu - gmake - grub-mkrescue - xorriso

BUILDING AND RUNNING XV6

run make qemu with a compiler capable of producing ELF files.

On linux-based systems and FreeBSD systems, this means the native compiler.

Note that make qemu -j16 will parallelize the build.

The password for the root and user accounts are both x. This is temporary until hashes are added in /etc/shadow.

Oh, and it runs DOOM.

(there is a video in docs/pictures, but github will not embed it)

TODO

• XHCI USB keyboard support