Commit graph

136 commits

Author SHA1 Message Date
rtm de1329dda2 longjmp -> swtch in comments 2007-08-30 17:39:56 +00:00
rsc 5573c8f296 delete proc_ on proc_exit, proc_wait, proc_kill 2007-08-28 19:14:43 +00:00
rsc 5516be1fed spaces around else for rtm 2007-08-28 18:37:41 +00:00
rsc e4d6a21165 more consistent spacing 2007-08-28 18:32:08 +00:00
rsc fc21046754 nit 2007-08-28 12:52:14 +00:00
rsc 818fc0125e replace setjmp/longjmp with swtch 2007-08-28 12:48:33 +00:00
rsc 558ab49f13 delete unnecessary #include lines 2007-08-27 23:26:33 +00:00
rsc 1ccff18b24 fileincref -> filedup (consistent with idup) 2007-08-27 14:35:09 +00:00
rsc 97ac612fb1 nits 2007-08-24 20:28:08 +00:00
rsc dd86897434 make wakeup1 static 2007-08-24 20:22:55 +00:00
rsc b1fb19b6df Use parent pointer instead of ppid. 2007-08-23 14:40:30 +00:00
rsc 3a057d12ae avoid hardcoding init as pid 1 proc[0] 2007-08-23 14:35:28 +00:00
rsc 1d7839a1da my mistake found by robert 2007-08-22 17:45:52 +00:00
rsc eaea18cb9c PDF at http://am.lcs.mit.edu/~rsc/xv6.pdf
Various changes made while offline.

 + bwrite sector argument is redundant; use b->sector.
 + reformatting of files for nicer PDF page breaks
 + distinguish between locked, unlocked inodes in type signatures
 + change FD_FILE to FD_INODE
 + move userinit (nee proc0init) to proc.c
 + move ROOTDEV to param.h
 + always parenthesize sizeof argument
2007-08-22 06:01:32 +00:00
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
rsc e2a620da49 checkpoint - simpler namei interface 2007-08-20 19:37:15 +00:00
rsc 07ddc0fa82 nit 2007-08-14 19:41:29 +00:00
rsc 2ef3a64bb4 Because limit gives the address of the last addressable
byte in the segment, the limit argument to SEG16 and SEG
needs to have 1 subtracted from it.
2007-08-14 04:55:45 +00:00
rsc b6095304b7 Make cp a magic symbol. 2007-08-10 16:37:27 +00:00
rsc 9583b476bf try to use cp only for curproc[cpu()] 2007-08-09 17:32:40 +00:00
rsc f2f062da61 check p->killed for long-lived sleeps 2007-08-08 10:29:42 +00:00
rsc c16e0916a7 cleaner table 2007-08-08 09:43:07 +00:00
rsc 19b1f63813 cleaner table 2007-08-08 09:42:36 +00:00
rsc d80b06a1e0 iincref returns new ref 2007-08-08 09:30:42 +00:00
rsc b6dc6187f7 add DPL_USER constant 2007-08-08 09:02:42 +00:00
rsc 00d0f794cf fix various bugs 2007-08-08 08:57:37 +00:00
rsc a7d18bb6f0 comment tweaks; more informative process list 2007-08-08 08:38:38 +00:00
rsc 1656b1b232 move growproc up higher 2006-09-08 14:26:51 +00:00
rsc d911d83ca1 fix various comments 2006-09-08 13:55:43 +00:00
rsc b6cac0a53b check preconditions in sched 2006-09-07 16:54:00 +00:00
rsc ab17e3198b debugging prints 2006-09-07 15:45:38 +00:00
rsc 31085bb416 more comments 2006-09-07 14:12:30 +00:00
rsc 1133b215d8 more defensive programming 2006-09-07 01:56:22 +00:00
rsc 50e514be98 fd_* => file_* 2006-09-06 18:43:45 +00:00
rsc 9936bffa45 fd.* -> file.* 2006-09-06 18:40:28 +00:00
rsc 39593d2f1a struct fd -> struct file 2006-09-06 18:38:56 +00:00
rsc f552738889 no /* */ comments 2006-09-06 17:50:20 +00:00
rsc 9e9bcaf143 standardize various * conventions 2006-09-06 17:27:19 +00:00
rsc 0992df4b90 clear np->mem after freeing 2006-09-06 16:35:21 +00:00
kaashoek 21a88dd053 some pipe support in sh
bug in proc_wait
2006-09-06 15:32:21 +00:00
rtm 2aa4c3bc29 complain if no disk 1
lots of cleanup
2006-08-30 18:55:06 +00:00
rtm 18432ed5ed nits 2006-08-29 21:35:30 +00:00
rtm 7a37578e9e clear killed flag in exit
idecref cwd in exit
2006-08-29 19:59:52 +00:00
rtm dfcc5b997c prune unneeded panics and debug output 2006-08-29 19:06:37 +00:00
rtm 3b95801add i broke sbrk, fix it 2006-08-29 17:01:40 +00:00
rtm 2b19190c13 clean up stale error checks and panics
delete unused functions
a few comments
2006-08-29 14:45:45 +00:00
kaashoek 81d5219998 bug in sbrk
test malloc
2006-08-24 19:24:36 +00:00
kaashoek ea2909b6b5 user-level malloc (untested)
nit in sbrk
indirect block
fix dup to share fd struct
2006-08-24 02:44:41 +00:00
kaashoek 8b58e81077 i/o redirection in sh
better parsing of sh commands (copied from jos sh)
cat: read from 1 if no args
sbrk system call, but untested
getpid system call
moved locks in keyboard intr, but why do we get intr w. null characters from keyboard?
2006-08-23 01:09:24 +00:00
kaashoek 8787cd01df chdir
cd in shell
nits in mkdir, ls, etc.
2006-08-19 23:41:34 +00:00
rtm 350e63f7a9 no more proc[] entry per cpu for idle loop
each cpu[] has its own gdt and tss
no per-proc gdt or tss, re-write cpu's in scheduler (you win, cliff)
main0() switches to cpu[0].mpstack
2006-08-15 22:18:20 +00:00
kaashoek e958c538fa commented out code for cwd 2006-08-15 15:53:46 +00:00
rtm 9e5970d596 link() 2006-08-13 02:12:44 +00:00
rtm 5be0039ce9 interrupts could be recursive since lapic_eoi() called before rti
so fast interrupts overflow the kernel stack
fix: cli() before lapic_eoi()
2006-08-10 22:08:14 +00:00
rtm 0e84a0ec6e fix race in holding() check in acquire()
give cpu1 a TSS and gdt for when it enters scheduler()
and a pseudo proc[] entry for each cpu
cpu0 waits for each other cpu to start up
read() for files
2006-08-08 19:58:06 +00:00
rtm 32630628a9 open() 2006-07-29 09:35:02 +00:00
rtm c59361f143 primitive exec 2006-07-27 21:10:00 +00:00
rtm bd228a8156 prevent longjmp / forkret from writing over tf->edi 2006-07-18 19:22:37 +00:00
rsc 0dd4253747 add ide_lock for sleep 2006-07-17 05:00:25 +00:00
rsc b5f17007f4 standarize on unix-like lowercase struct names 2006-07-17 01:58:13 +00:00
rsc b5ee516575 add uint and standardize on typedefs instead of unsigned 2006-07-17 01:52:13 +00:00
rsc ee9c7f3bfc goodbye PushRegs 2006-07-17 01:36:39 +00:00
rsc c54c79267f nitpicks 2006-07-17 01:25:22 +00:00
rsc 564f787e91 Eliminate annoying Pseudodesc structure.
Eliminate unnecessary parts of mmu.h.
2006-07-16 16:55:52 +00:00
rsc ef2bd07ae4 standardize on not using foo_ prefix in struct foo 2006-07-16 15:41:47 +00:00
rsc 51716a869c Rename fd_reference to more suggestive fd_incref.
(Fd_reference sounds like it might just return the ref count.)
2006-07-16 01:49:03 +00:00
rsc 856e1fc1ad Attempt to clean up newproc somewhat.
Also remove all calls to memcpy in favor of
memmove, which has defined semantics when
the ranges overlap.  The fact that memcpy was
working in console.c to scroll the screen is not
guaranteed by all implementations.
2006-07-16 01:47:40 +00:00
rsc 65bd8e139a New scheduler.
Removed cli and sti stack in favor of tracking
number of locks held on each CPU and explicit
conditionals in spinlock.c.
2006-07-16 01:15:28 +00:00
rsc 643b122b4a move everything having to do with proc_table_lock into proc.c 2006-07-15 17:24:54 +00:00
rtm 46bbd72f3e no more recursive locks
wakeup1() assumes you hold proc_table_lock
sleep(chan, lock) provides atomic sleep-and-release to wait for condition
ugly code in swtch/scheduler to implement new sleep
fix lots of bugs in pipes, wait, and exit
fix bugs if timer interrupt goes off in schedule()
console locks per line, not per byte
2006-07-15 12:03:57 +00:00
rtm 6eb6f10c56 passes both usertests
exit had acquire where I meant release
swtch now checks that you hold no locks
2006-07-12 15:35:33 +00:00
rtm 8148b6ee53 i think my cmpxchg use was wrong in acquire
nesting cli/sti: release shouldn't always enable interrupts
separate setup of lapic from starting of other cpus, so cpu() works earlier
flag to disable locking in console output
make locks work even when curproc==0
(still crashes in clock interrupt)
2006-07-12 11:15:38 +00:00
rtm 664324745e cvs add spinlock.h
fix race in schedule()
2006-07-12 09:10:25 +00:00
rtm 4e8f237be8 no more big kernel lock
succeeds at usertests.c pipe test
2006-07-12 01:48:35 +00:00
rtm b548df152b pre-empt both user and kernel, in clock interrupt
usertest.c tests pre-emption
kill()
2006-07-11 17:39:45 +00:00
rsc 5ce9751cab Changes to allow use of native x86 ELF compilers, which on my
Linux 2.4 box using gcc 3.4.6 don't seem to follow the same
conventions as the i386-jos-elf-gcc compilers.
Can run make 'TOOLPREFIX=' or edit the Makefile.

curproc[cpu()] can now be NULL, indicating that no proc is running.
This seemed safer to me than having curproc[0] and curproc[1]
both pointing at proc[0] potentially.

The old implementation of swtch depended on the stack frame layout
used inside swtch being okay to return from on the other stack
(exactly the V6 you are not expected to understand this).
It also could be called in two contexts: at boot time, to schedule
the very first process, and later, on behalf of a process, to sleep
or schedule some other process.

I split this into two functions: scheduler and swtch.

The scheduler is now a separate never-returning function, invoked
by each cpu once set up.  The scheduler looks like:

	scheduler() {
		setjmp(cpu.context);

		pick proc to schedule
		blah blah blah

		longjmp(proc.context)
	}

The new swtch is intended to be called only when curproc[cpu()] is not NULL,
that is, only on behalf of a user proc.  It does:

	swtch() {
		if(setjmp(proc.context) == 0)
			longjmp(cpu.context)
	}

to save the current proc context and then jump over to the scheduler,
running on the cpu stack.

Similarly the system call stubs are now in assembly in usys.S to avoid
needing to know the details of stack frame layout used by the compiler.

Also various changes in the debugging prints.
2006-07-11 01:07:40 +00:00
rtm 8b4e2a08fe swtch saves callee-saved registers
swtch idles on per-CPU stack, not on calling process's stack
fix pipe bugs
usertest.c tests pipes, fork, exit, close
2006-07-01 21:26:01 +00:00
rtm c41f1de5d4 file descriptors
pipes
2006-06-27 14:35:53 +00:00
rtm b61c2547b8 system call return values
initialize 2nd cpu's idt
2006-06-26 20:31:52 +00:00
rtm bf3903612d system call arguments 2006-06-26 15:11:19 +00:00
rtm 89eb5fbe6d boot more than two CPUs, each on own initial stack 2006-06-24 22:47:06 +00:00
rtm df5cc91659 compile "user programs"
curproc array
2006-06-22 20:47:23 +00:00
rtm be0a7eacda sleep, wakeup, wait, exit 2006-06-15 19:58:01 +00:00
rtm a4c03dea09 primitive fork and exit system calls 2006-06-15 16:02:20 +00:00
rtm 0a70d042d0 more or less take traps/interrupts 2006-06-13 15:50:06 +00:00
rtm 55e95b16db import 2006-06-12 15:22:12 +00:00