Commit graph

12 commits

Author SHA1 Message Date
kaashoek
939f9edeac iread for T_DEV
O_RDWR, etc.
create file
2006-08-09 19:25:20 +00:00
kaashoek
2601de0032 fix test program: don't close before writing
set fd to writeable on open for write
2006-08-09 17:25:10 +00:00
kaashoek
6fa5ffb56f devsw
checkpoint: write(fd,"hello\n",6) where fd is a console dev almost works
2006-08-09 16:04:04 +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
kaashoek
e8d11c2e84 mknod,ialloc,iupdate 2006-08-08 18:07:37 +00:00
rtm
32630628a9 open() 2006-07-29 09:35:02 +00:00
rtm
8455980b27 exec arguments 2006-07-28 22:33:07 +00:00
rtm
c59361f143 primitive exec 2006-07-27 21:10:00 +00:00
rsc
c54c79267f nitpicks 2006-07-17 01:25:22 +00:00
rsc
9b37d1bfaa Add user.h for prototypes.
Add cons_puts for cleaner output.
2006-07-16 15:36:31 +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
kaashoek
084f21430c oops 2006-07-10 16:27:15 +00:00