diff --git a/Makefile b/Makefile index 0b716b4..f82d260 100644 --- a/Makefile +++ b/Makefile @@ -5,7 +5,7 @@ CC = i386-jos-elf-gcc LD = i386-jos-elf-ld OBJCOPY = i386-jos-elf-objcopy OBJDUMP = i386-jos-elf-objdump -CFLAGS = -nostdinc -I. -O -Wall -MD +CFLAGS = -nostdinc -I. -O2 -Wall -MD xv6.img : bootblock kernel dd if=/dev/zero of=xv6.img count=10000 diff --git a/fd.c b/fd.c index 0546cef..8b59605 100644 --- a/fd.c +++ b/fd.c @@ -37,19 +37,6 @@ fd_alloc() return 0; } -void -fd_close(struct fd *fd) -{ - if(fd->type == FD_CLOSED || fd->count <= 0) - panic("fd_close"); - fd->count -= 1; - if(fd->count == 0){ - if(fd->type == FD_PIPE) - pipe_close(fd->pipe, fd->writeable); - fd->type = FD_CLOSED; - } -} - /* * addr is a kernel address, pointing into some process's p->mem. */ @@ -78,3 +65,20 @@ fd_read(struct fd *fd, char *addr, int n) return -1; } } + +void +fd_close(struct fd *fd) +{ + if(fd->count < 1 || fd->type == FD_CLOSED) + panic("fd_close"); + fd->count -= 1; + + if(fd->count == 0){ + if(fd->type == FD_PIPE){ + pipe_close(fd->pipe, fd->writeable); + } else { + panic("fd_close"); + } + fd->type = FD_CLOSED; + } +} diff --git a/kalloc.c b/kalloc.c index 5ea38fd..1944508 100644 --- a/kalloc.c +++ b/kalloc.c @@ -45,10 +45,15 @@ kfree(char *cp, int len) struct run **rr; struct run *p = (struct run *) cp; struct run *pend = (struct run *) (cp + len); + int i; if(len % PAGE) panic("kfree"); + // XXX fill with junk to help debug + for(i = 0; i < len; i++) + cp[i] = 1; + rr = &freelist; while(*rr){ struct run *rend = (struct run *) ((char *)(*rr) + (*rr)->len); diff --git a/main.c b/main.c index 979048c..4c2a2f9 100644 --- a/main.c +++ b/main.c @@ -46,7 +46,7 @@ main() p = &proc[0]; curproc[cpu()] = p; p->state = WAITING; - p->sz = PAGE; + p->sz = 4 * PAGE; p->mem = kalloc(p->sz); memset(p->mem, 0, p->sz); p->kstack = kalloc(KSTACKSIZE); diff --git a/mp.c b/mp.c index eb5afc9..57b887d 100644 --- a/mp.c +++ b/mp.c @@ -6,6 +6,7 @@ #include "x86.h" #include "traps.h" #include "mmu.h" +#include "proc.h" /* * Credit: Plan 9 sources, Intel MP spec, and Cliff Frey @@ -92,16 +93,11 @@ enum { /* LAPIC_TDCR */ }; #define APBOOTCODE 0x7000 // XXX hack -#define MPSTACK 512 static struct MP* mp; // The MP floating point structure static uint32_t *lapicaddr; -static struct cpu { - uint8_t apicid; // Local APIC ID - int lintr[2]; // Local APIC - char mpstack[MPSTACK]; // per-cpu start-up stack, only used to get into main() -} cpus[NCPU]; -static int ncpu; +struct cpu cpus[NCPU]; +int ncpu; static struct cpu *bcpu; static int @@ -130,7 +126,7 @@ lapic_timerinit() void lapic_timerintr() { - cprintf("%d: timer interrupt!\n", cpu()); + // cprintf("%d: timer interrupt!\n", cpu()); lapic_write (LAPIC_EOI, 0); } diff --git a/pipe.c b/pipe.c index 9a81e0b..3aed4e9 100644 --- a/pipe.c +++ b/pipe.c @@ -28,6 +28,10 @@ pipe_alloc(struct fd **fd1, struct fd **fd2) goto oops; if((p = (struct pipe *) kalloc(PAGE)) == 0) goto oops; + p->readopen = 1; + p->writeopen = 1; + p->writep = 0; + p->readp = 0; (*fd1)->type = FD_PIPE; (*fd1)->readable = 1; (*fd1)->writeable = 0; @@ -54,10 +58,13 @@ pipe_alloc(struct fd **fd1, struct fd **fd2) void pipe_close(struct pipe *p, int writeable) { - if(writeable) + if(writeable){ p->writeopen = 0; - else + wakeup(&p->readp); + } else { p->readopen = 0; + wakeup(&p->writep); + } if(p->readopen == 0 && p->writeopen == 0) kfree((char *) p, PAGE); } @@ -71,11 +78,13 @@ pipe_write(struct pipe *p, char *addr, int n) while(((p->writep + 1) % PIPESIZE) == p->readp){ if(p->readopen == 0) return -1; + wakeup(&p->readp); sleep(&p->writep); } p->data[p->writep] = addr[i]; p->writep = (p->writep + 1) % PIPESIZE; } + wakeup(&p->readp); return i; } @@ -96,5 +105,6 @@ pipe_read(struct pipe *p, char *addr, int n) addr[i] = p->data[p->readp]; p->readp = (p->readp + 1) % PIPESIZE; } + wakeup(&p->writep); return i; } diff --git a/proc.c b/proc.c index 97e84e3..8ad6a23 100644 --- a/proc.c +++ b/proc.c @@ -104,37 +104,47 @@ swtch() { struct proc *np; struct proc *op = curproc[cpu()]; - - while(1){ - np = op + 1; - while(np != op){ - if(np->state == RUNNABLE) - break; - np++; - if(np == &proc[NPROC]) - np = &proc[0]; - } - if(np->state == RUNNABLE) - break; - // cprintf("swtch: nothing to run\n"); - release_spinlock(&kernel_lock); - acquire_spinlock(&kernel_lock); - } - - // XXX this may be too late, should probably save on the way - // in, in case some other CPU decided to run curproc - // before we got here. in fact setting state=WAITING and - // setting these variables had better be atomic w.r.t. other CPUs. + unsigned sp; + int i; + + // force push of callee-saved registers + asm volatile("nop" : : : "%edi", "%esi", "%ebx"); + + // save calling process's stack pointers op->ebp = read_ebp(); op->esp = read_esp(); - cprintf("cpu %d swtch %x -> %x\n", cpu(), op, np); + // don't execute on calling process's stack + sp = (unsigned) cpus[cpu()].mpstack + MPSTACK - 32; + asm volatile("movl %0, %%esp" : : "g" (sp)); + asm volatile("movl %0, %%ebp" : : "g" (sp)); + + // gcc might store op on the stack + np = curproc[cpu()]; + np = np + 1; + + while(1){ + for(i = 0; i < NPROC; i++){ + if(np >= &proc[NPROC]) + np = &proc[0]; + if(np->state == RUNNABLE) + break; + np++; + } + if(i < NPROC) + break; + // cprintf("swtch %d: nothing to run %d %d\n", + // cpu(), proc[1].state, proc[2].state); + release_spinlock(&kernel_lock); + acquire_spinlock(&kernel_lock); + np = &proc[0]; + } + + cprintf("cpu %d swtch %x -> %x\n", cpu(), curproc[cpu()], np); curproc[cpu()] = np; np->state = RUNNING; - // XXX callee-saved registers? - // h/w sets busy bit in TSS descriptor sometimes, and faults // if it's set in LTR. so clear tss descriptor busy bit. np->gdt[SEG_TSS].sd_type = STS_T32A; diff --git a/proc.h b/proc.h index 14164db..e371f7d 100644 --- a/proc.h +++ b/proc.h @@ -37,3 +37,14 @@ struct proc{ extern struct proc proc[]; extern struct proc *curproc[NCPU]; + +#define MPSTACK 512 + +struct cpu { + uint8_t apicid; // Local APIC ID + int lintr[2]; // Local APIC + char mpstack[MPSTACK]; // per-cpu start-up stack, only used to get into main() +}; + +extern struct cpu cpus[NCPU]; +extern int ncpu; diff --git a/syscall.c b/syscall.c index c27c226..6343531 100644 --- a/syscall.c +++ b/syscall.c @@ -91,7 +91,7 @@ sys_pipe() int sys_write() { - int fd, n; + int fd, n, ret; unsigned addr; struct proc *p = curproc[cpu()]; @@ -103,13 +103,14 @@ sys_write() return -1; if(addr + n > p->sz) return -1; - return fd_write(p->fds[fd], p->mem + addr, n); + ret = fd_write(p->fds[fd], p->mem + addr, n); + return ret; } int sys_read() { - int fd, n; + int fd, n, ret; unsigned addr; struct proc *p = curproc[cpu()]; @@ -121,7 +122,25 @@ sys_read() return -1; if(addr + n > p->sz) return -1; - return fd_read(p->fds[fd], p->mem + addr, n); + ret = fd_read(p->fds[fd], p->mem + addr, n); + return ret; +} + +int +sys_close() +{ + int fd; + struct proc *p = curproc[cpu()]; + + if(fetcharg(0, &fd) < 0) + return -1; + if(fd < 0 || fd >= NOFILE) + return -1; + if(p->fds[fd] == 0) + return -1; + fd_close(p->fds[fd]); + p->fds[fd] = 0; + return 0; } int @@ -138,6 +157,14 @@ sys_exit() { struct proc *p; struct proc *cp = curproc[cpu()]; + int fd; + + for(fd = 0; fd < NOFILE; fd++){ + if(cp->fds[fd]){ + fd_close(cp->fds[fd]); + cp->fds[fd] = 0; + } + } cp->state = ZOMBIE; @@ -227,6 +254,9 @@ syscall() case SYS_read: ret = sys_read(); break; + case SYS_close: + ret = sys_close(); + break; default: cprintf("unknown sys call %d\n", num); // XXX fault diff --git a/syscall.h b/syscall.h index 65d5ced..764b46f 100644 --- a/syscall.h +++ b/syscall.h @@ -5,3 +5,4 @@ #define SYS_pipe 5 #define SYS_write 6 #define SYS_read 7 +#define SYS_close 8 diff --git a/trap.c b/trap.c index 01c2f14..e36540d 100644 --- a/trap.c +++ b/trap.c @@ -35,16 +35,28 @@ trap(struct Trapframe *tf) { int v = tf->tf_trapno; + if(tf->tf_cs == 0x8 && kernel_lock == cpu()) + cprintf("cpu %d: trap from %x:%x with lock=%d\n", + cpu(), tf->tf_cs, tf->tf_eip, kernel_lock); + acquire_spinlock(&kernel_lock); // released in trapret in trapasm.S if(v == T_SYSCALL){ - curproc[cpu()]->tf = tf; + struct proc *cp = curproc[cpu()]; + cp->tf = tf; syscall(); + if(cp != curproc[cpu()]) + panic("trap ret wrong curproc"); + if(cp->state != RUNNING) + panic("trap ret but not RUNNING"); + if(tf != cp->tf) + panic("trap ret wrong tf"); + if(read_esp() < cp->kstack || read_esp() >= cp->kstack + KSTACKSIZE) + panic("trap ret esp wrong"); return; } if(v == (IRQ_OFFSET + IRQ_TIMER)){ - curproc[cpu()]->tf = tf; lapic_timerintr(); return; } diff --git a/ulib.c b/ulib.c index 694501e..d99acdd 100644 --- a/ulib.c +++ b/ulib.c @@ -5,6 +5,13 @@ fork() asm("int $48"); } +int +exit() +{ + asm("mov $2, %eax"); + asm("int $48"); +} + void cons_putc(int c) { @@ -42,3 +49,10 @@ write(int fd, char *buf, int n) asm("mov $6, %eax"); asm("int $48"); } + +int +close(int fd) +{ + asm("mov $8, %eax"); + asm("int $48"); +} diff --git a/usertests.c b/usertests.c index 62eefda..37540db 100644 --- a/usertests.c +++ b/usertests.c @@ -1,22 +1,48 @@ // simple fork and pipe read/write -char buf[32]; +char buf[2048]; void pipe1() { int fds[2], pid; + int seq = 0, i, n, cc, total; pipe(fds); - pid = pipe(); + pid = fork(); if(pid == 0){ - write(fds[1], "xyz", 4); - } else { - read(fds[0], buf, sizeof(buf)); - if(buf[0] != 'x' || buf[1] != 'y'){ - puts("pipe1 oops\n"); - return; + close(fds[0]); + for(n = 0; n < 5; n++){ + for(i = 0; i < 1033; i++) + buf[i] = seq++; + if(write(fds[1], buf, 1033) != 1033){ + puts("pipe1 oops 1\n"); + exit(1); + } } + exit(0); + } else { + close(fds[1]); + total = 0; + cc = 1; + while(1){ + n = read(fds[0], buf, cc); + if(n < 1) + break; + for(i = 0; i < n; i++){ + if((buf[i] & 0xff) != (seq++ & 0xff)){ + puts("pipe1 oops 2\n"); + return; + } + } + total += n; + cc = cc * 2; + if(cc > sizeof(buf)) + cc = sizeof(buf); + } + if(total != 5 * 1033) + puts("pipe1 oops 3\n"); + close(fds[0]); } puts("pipe1 ok\n"); } diff --git a/x86.h b/x86.h index b905f83..7bc677f 100644 --- a/x86.h +++ b/x86.h @@ -244,6 +244,30 @@ read_esp(void) return esp; } +static __inline uint32_t +read_esi(void) +{ + uint32_t esi; + __asm __volatile("movl %%esi,%0" : "=r" (esi)); + return esi; +} + +static __inline uint32_t +read_edi(void) +{ + uint32_t edi; + __asm __volatile("movl %%edi,%0" : "=r" (edi)); + return edi; +} + +static __inline uint32_t +read_ebx(void) +{ + uint32_t ebx; + __asm __volatile("movl %%ebx,%0" : "=r" (ebx)); + return ebx; +} + static __inline void cpuid(uint32_t info, uint32_t *eaxp, uint32_t *ebxp, uint32_t *ecxp, uint32_t *edxp) { @@ -280,6 +304,20 @@ read_tsc(void) return tsc; } +// disable interrupts +static __inline void +cli(void) +{ + __asm __volatile("cli"); +} + +// enable interrupts +static __inline void +sti(void) +{ + __asm __volatile("sti"); +} + struct PushRegs { /* registers as pushed by pusha */ uint32_t reg_edi;