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2006-09-07nit in console interruptskaashoek1-2/+3
2006-09-03don't send keyboard interrupts to the second cpu, if we have only one cpu.kaashoek1-1/+0
xv6 seems to work fine on uniprocessor now.
2006-08-30complain if no disk 1rtm1-0/+1
lots of cleanup
2006-08-29nitsrtm1-2/+2
2006-08-29clean up stale error checks and panicsrtm1-35/+9
delete unused functions a few comments
2006-08-26mkdir check error from mknodrtm1-8/+1
chdir return -1 if target not a dir
2006-08-25inode addrs[NDIRECT] -> NADDRSrtm1-0/+5
fix race in mknod / creat use last component in dirent in mknod, not path
2006-08-24big directory testrtm1-1/+10
2006-08-23i/o redirection in shkaashoek1-0/+8
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?
2006-08-15no more proc[] entry per cpu for idle looprtm1-263/+22
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
2006-08-13fix iget() bug that allocated in-use inode[] entriesrtm1-11/+3
2006-08-13namei returns locked parent dir inode for create / unlinkrtm1-0/+15
don't hold fd table lock across idecref() (latter does block i/o) idecref calls iput() in case last ref -> freeing inode dir size is 512 * # blocks, so readi/writei &c work unlink deletes dirent even if ip->nlink > 0
2006-08-13link()rtm1-2/+2
2006-08-12zero out all of dirent.name when creatingrtm1-2/+2
don't increase length of directory
2006-08-12LRU disk cache replacementrtm1-0/+8
2006-08-12buffer cache, fifo replacementrtm1-0/+3
2006-08-10interrupts could be recursive since lapic_eoi() called before rtirtm1-0/+75
so fast interrupts overflow the kernel stack fix: cli() before lapic_eoi()
2006-08-10low-level keyboard input (not hooked up to /dev yet)rtm1-0/+38
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...
2006-08-08fix race in holding() check in acquire()rtm1-0/+78
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
2006-07-28exec argumentsrtm1-0/+2
2006-07-21nameirtm1-3/+15
2006-07-15no more recursive locksrtm1-0/+23
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
2006-07-12passes both usertestsrtm1-17/+6
exit had acquire where I meant release swtch now checks that you hold no locks
2006-07-12i think my cmpxchg use was wrong in acquirertm1-0/+4
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)
2006-07-12cvs add spinlock.hrtm1-0/+7
fix race in schedule()
2006-07-12no more big kernel lockrtm1-11/+38
succeeds at usertests.c pipe test
2006-07-11pre-empt both user and kernel, in clock interruptrtm1-12/+18
usertest.c tests pre-emption kill()
2006-07-11Changes to allow use of native x86 ELF compilers, which on myrsc1-0/+2
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.
2006-06-27file descriptorsrtm1-0/+8
pipes
2006-06-22send console output to parallel portrtm1-0/+3
2006-06-15primitive fork and exit system callsrtm1-0/+1
2006-06-13fix some trap bugsrtm1-0/+6
2006-06-13more or less take traps/interruptsrtm1-0/+8
2006-06-12importrtm1-0/+67