xv6 is a modern re-implementation of Sixth Edition Unix in ANSI C for multiprocessor x86/x86_64 systems.
Find a file
rsc f32f3638f4 Various cleanup:
- Got rid of dummy proc[0].  Now proc[0] is init.
 - Added initcode.S to exec /init, so that /init is
   just a regular binary.
 - Moved exec out of sysfile to exec.c
 - Moved code dealing with fs guts (like struct inode)
   from sysfile.c to fs.c.  Code dealing with system call
   arguments stays in sysfile.c
 - Refactored directory routines in fs.c; should be simpler.
 - Changed iget to return *unlocked* inode structure.
   This solves the lookup-then-use race in namei
   without introducing deadlocks.
   It also enabled getting rid of the dummy proc[0].
2007-08-21 19:22:08 +00:00
.cvsignore New formatting scripts. 2006-09-05 15:50:55 +00:00
8253pit.c xv6 style 2006-09-08 14:41:18 +00:00
asm.h wrap long lines 2006-09-06 19:08:14 +00:00
bio.c cleanup loop 2007-08-14 19:42:14 +00:00
bootasm.S shorten 2006-09-08 15:31:23 +00:00
bootmain.c wrap long lines 2006-09-06 19:08:14 +00:00
bootother.S wrap long lines 2006-09-06 19:08:14 +00:00
buf.h some comment changes 2006-09-08 14:36:44 +00:00
BUGS Various cleanup: 2007-08-21 19:22:08 +00:00
cat.c standardize various * conventions 2006-09-06 17:27:19 +00:00
console.c fixes 2007-08-14 19:41:01 +00:00
defs.h Various cleanup: 2007-08-21 19:22:08 +00:00
dev.h remove _ prefixes 2006-09-07 13:08:23 +00:00
dot-bochsrc update 2006-07-26 10:17:39 +00:00
echo.c i/o redirection in sh 2006-08-23 01:09:24 +00:00
elf.h more comments 2006-09-07 14:12:30 +00:00
exec.c Various cleanup: 2007-08-21 19:22:08 +00:00
fcntl.h low-level keyboard input (not hooked up to /dev yet) 2006-08-10 02:07:10 +00:00
file.c formatting, cleanup 2007-08-14 19:41:56 +00:00
file.h fd.* -> file.* 2006-09-06 18:40:28 +00:00
fs.c Various cleanup: 2007-08-21 19:22:08 +00:00
fs.h shuffle fs.c in bottom-up order 2007-08-20 18:23:52 +00:00
fsvar.h Various cleanup: 2007-08-21 19:22:08 +00:00
ide.c formatting, sleep bug fix 2007-08-14 18:46:29 +00:00
init.c watch for zombies 2007-08-08 08:57:03 +00:00
initcode.S Various cleanup: 2007-08-21 19:22:08 +00:00
ioapic.c formatting nits 2006-09-08 15:14:43 +00:00
ioapic.h wrap long lines 2006-09-06 19:08:14 +00:00
kalloc.c formatting, simplify 2007-08-14 19:05:48 +00:00
kbd.h formatting; split kbd constants into kbd.h 2007-08-14 19:31:16 +00:00
kill.c add kill 2007-08-08 08:50:23 +00:00
lapic.c replace bogus loops with slightly less bogus loops. 2007-08-10 17:05:46 +00:00
ls.c make ls work on directories 2007-08-08 09:17:09 +00:00
main.c Various cleanup: 2007-08-21 19:22:08 +00:00
Makefile Various cleanup: 2007-08-21 19:22:08 +00:00
mkdir.c more comments 2006-09-07 14:12:30 +00:00
mkfs.c quiet 2006-09-08 13:44:56 +00:00
mmu.h formatting 2007-08-14 19:41:38 +00:00
mp.c nit 2006-09-08 15:15:44 +00:00
mp.h wrap long lines 2006-09-06 19:08:14 +00:00
Notes nit in console interrupts 2006-09-07 00:00:33 +00:00
param.h struct fd -> struct file 2006-09-06 18:38:56 +00:00
picirq.c fix ide, pit interfaces 2006-09-07 15:29:54 +00:00
pipe.c i cannot prove that release before wakeup is wrong, but i cannot convince myself it is right either 2007-08-14 19:10:57 +00:00
pr.pl runoff changes 2006-09-08 13:53:18 +00:00
printf.c avoid assignments in declarations 2007-08-10 17:17:42 +00:00
proc.c Various cleanup: 2007-08-21 19:22:08 +00:00
proc.h Make cp a magic symbol. 2007-08-10 16:37:27 +00:00
README 2007 2007-08-08 10:27:15 +00:00
rm.c fix error message 2007-08-08 09:30:58 +00:00
runoff formatting 2007-08-14 18:42:34 +00:00
runoff.list formatting; split kbd constants into kbd.h 2007-08-14 19:31:16 +00:00
runoff.spec formatting 2007-08-14 18:42:34 +00:00
runoff1 correct line numbers 2007-08-10 17:45:14 +00:00
setjmp.S make setjmp fit on one page 2006-09-08 14:20:43 +00:00
sh.c cleanup main 2007-08-10 17:00:00 +00:00
show1 formatting 2007-08-14 18:42:34 +00:00
sign.pl spacing fixes: no tabs, 2-space indents (for rtm) 2006-09-06 17:04:06 +00:00
spinlock.c nit 2007-08-10 17:45:49 +00:00
spinlock.h more comments 2006-09-07 14:12:30 +00:00
stat.h more comments 2006-09-07 14:12:30 +00:00
string.c Various cleanup: 2007-08-21 19:22:08 +00:00
syscall.c Various cleanup: 2007-08-21 19:22:08 +00:00
syscall.h refactor syscall code 2006-09-07 14:13:26 +00:00
sysfile.c Various cleanup: 2007-08-21 19:22:08 +00:00
sysproc.c Make cp a magic symbol. 2007-08-10 16:37:27 +00:00
toc.ftr fix toc example 2006-09-08 15:39:24 +00:00
toc.hdr runoff changes 2006-09-08 13:53:18 +00:00
trap.c formatting 2007-08-14 18:42:34 +00:00
trapasm.S standardize various * conventions 2006-09-06 17:27:19 +00:00
traps.h typo 2007-08-08 08:27:32 +00:00
types.h uint32_t -> uint &c 2006-07-20 09:07:53 +00:00
ulib.c avoid assignments in declarations 2007-08-10 17:17:42 +00:00
umalloc.c avoid assignments in declarations 2007-08-10 17:17:42 +00:00
user.h standardize on not using unsigned keyword 2007-08-08 09:30:48 +00:00
usertests.c bug in usertests! 2007-08-20 21:00:20 +00:00
usys.S standardize various * conventions 2006-09-06 17:27:19 +00:00
vectors.pl no /* */ comments 2006-09-06 17:50:20 +00:00
x86.h no more w 2007-08-20 18:55:51 +00:00
xv6-rev0.tar.gz dist tarball 2006-09-08 15:44:42 +00:00
xv6.pdf sent to printer - CTC job 6955 40 copies 2006-09-08 15:55:26 +00:00
xv6.ps a copy of xv6.pdf that can be sent to turkey and duplexes correctly 2006-09-08 16:19:26 +00:00
zombie.c spacing 2007-08-08 08:44:11 +00:00

xv6 is a re-implementation of Dennis Ritchie's and Ken Thompson's Unix
Version 6 (v6).  xv6 loosely follows the structure and style of v6,
but is implemented for a modern x86-based multiprocessor using ANSI C.

ACKNOWLEDGEMENTS

xv6 is inspired by John Lions' Commentary on UNIX 6th Edition (Peer
to Peer Communications; ISBN: 1-57398-013-7; 1st edition (June 14,
2000)). See also http://pdos.csail.mit.edu/6.828/2007/v6.html, which
provides pointers to on-line resources for v6.

xv6 borrows code from the following sources:
    JOS (asm.h, elf.h, mmu.h, bootasm.S, ide.c, console.c, and others)
    Plan 9 (bootother.S, mp.h, mp.c, ioapic.h, lapic.c)
    FreeBSD (ioapic.c)
    NetBSD (console.c)

The following people made contributions:
    Russ Cox (context switching, locking)
    Cliff Frey (MP)
    Xiao Yu (MP)

The code in the files that constitute xv6 are 
Copyright 2006-2007 Frans Kaashoek, Robert Morris, and Russ Cox.

ERROR REPORTS

If you spot errors or have suggestions for improvement, please send
email to Frans Kaashoek and Robert Morris
({kaashoek,rtm}@csail.mit.edu).  This version is the very first one,
so don't be surprised if there are errors or the code is unclear.

BUIDLING AND RUNNING XV6

To build xv6 on an x86 ELF machine (like Linux or FreeBSD), run "make".
On non-x86 or non-ELF machines (like OS X, even on x86), you will
need to install a cross-compiler gcc suite capable of producing x86 ELF
binaries.  See http://pdos.csail.mit.edu/6.828/2007/tools.html.
Then run "make TOOLPREFIX=i386-jos-elf-".

To run xv6, you can use Bochs or QEMU, both PC simulators.  Bochs makes
debugging easier, but QEMU is much faster. 
To run in Bochs, run "make bochs" and then type "c" at the bochs prompt.
To run in QEMU, run "make qemu".  Both log the xv6 screen output to 
standard output.

To create a typeset version of the code, run "make xv6.pdf".
This requires the "mpage" text formatting utility.
See http://www.mesa.nl/pub/mpage/.