irixsig.c

LINUX 2.6.17.4的源码

	while (1) {
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		if (do_irix_signal(&saveset, regs))
			return -EINTR;
	}
}

/* hate hate hate... */
struct irix5_siginfo {
	int sig, code, error;
	union {
		char unused[128 - (3 * 4)]; /* Safety net. */
		struct {
			int pid;
			union {
				int uid;
				struct {
					int utime, status, stime;
				} child;
			} procdata;
		} procinfo;

		unsigned long fault_addr;

		struct {
			int fd;
			long band;
		} fileinfo;

		unsigned long sigval;
	} stuff;
};

asmlinkage int irix_sigpoll_sys(unsigned long __user *set,
	struct irix5_siginfo __user *info, struct timespec __user *tp)
{
	long expire = MAX_SCHEDULE_TIMEOUT;
	sigset_t kset;
	int i, sig, error, timeo = 0;
	struct timespec ktp;

#ifdef DEBUG_SIG
	printk("[%s:%d] irix_sigpoll_sys(%p,%p,%p)\n",
	       current->comm, current->pid, set, info, tp);
#endif

	/* Must always specify the signal set. */
	if (!set)
		return -EINVAL;

	if (copy_from_user(&kset, set, sizeof(set)))
		return -EFAULT;

	if (info && clear_user(info, sizeof(*info))) {
		error = -EFAULT;
		goto out;
	}

	if (tp) {
		if (copy_from_user(&ktp, tp, sizeof(*tp)))
			return -EFAULT;

		if (!ktp.tv_sec && !ktp.tv_nsec)
			return -EINVAL;

		expire = timespec_to_jiffies(&ktp) +
		         (ktp.tv_sec || ktp.tv_nsec);
	}

	while(1) {
		long tmp = 0;

		expire = schedule_timeout_interruptible(expire);

		for (i=0; i<=4; i++)
			tmp |= (current->pending.signal.sig[i] & kset.sig[i]);

		if (tmp)
			break;
		if (!expire) {
			timeo = 1;
			break;
		}
		if (signal_pending(current))
			return -EINTR;
	}
	if (timeo)
		return -EAGAIN;

	for (sig = 1; i <= 65 /* IRIX_NSIG */; sig++) {
		if (sigismember (&kset, sig))
			continue;
		if (sigismember (&current->pending.signal, sig)) {
			/* XXX need more than this... */
			if (info)
				return copy_to_user(&info->sig, &sig, sizeof(sig));
			return 0;
		}
	}

	/* Should not get here, but do something sane if we do. */
	error = -EINTR;

out:
	return error;
}

/* This is here because of irix5_siginfo definition. */
#define IRIX_P_PID    0
#define IRIX_P_PGID   2
#define IRIX_P_ALL    7

extern int getrusage(struct task_struct *, int, struct rusage __user *);

#define W_EXITED     1
#define W_TRAPPED    2
#define W_STOPPED    4
#define W_CONT       8
#define W_NOHANG    64

#define W_MASK      (W_EXITED | W_TRAPPED | W_STOPPED | W_CONT | W_NOHANG)

asmlinkage int irix_waitsys(int type, int pid,
	struct irix5_siginfo __user *info, int options,
	struct rusage __user *ru)
{
	int flag, retval;
	DECLARE_WAITQUEUE(wait, current);
	struct task_struct *tsk;
	struct task_struct *p;
	struct list_head *_p;

	if (!info)
		return -EINVAL;

	if (!access_ok(VERIFY_WRITE, info, sizeof(*info)))
		return -EFAULT;

	if (ru)
		if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)))
			return -EFAULT;

	if (options & ~W_MASK)
		return -EINVAL;

	if (type != IRIX_P_PID && type != IRIX_P_PGID && type != IRIX_P_ALL)
		return -EINVAL;

	add_wait_queue(&current->signal->wait_chldexit, &wait);
repeat:
	flag = 0;
	current->state = TASK_INTERRUPTIBLE;
	read_lock(&tasklist_lock);
	tsk = current;
	list_for_each(_p,&tsk->children) {
		p = list_entry(_p,struct task_struct,sibling);
		if ((type == IRIX_P_PID) && p->pid != pid)
			continue;
		if ((type == IRIX_P_PGID) && process_group(p) != pid)
			continue;
		if ((p->exit_signal != SIGCHLD))
			continue;
		flag = 1;
		switch (p->state) {
		case TASK_STOPPED:
			if (!p->exit_code)
				continue;
			if (!(options & (W_TRAPPED|W_STOPPED)) &&
			    !(p->ptrace & PT_PTRACED))
				continue;
			read_unlock(&tasklist_lock);

			/* move to end of parent's list to avoid starvation */
			write_lock_irq(&tasklist_lock);
			remove_parent(p);
			add_parent(p);
			write_unlock_irq(&tasklist_lock);
			retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
			if (retval)
				goto end_waitsys;

			retval = __put_user(SIGCHLD, &info->sig);
			retval |= __put_user(0, &info->code);
			retval |= __put_user(p->pid, &info->stuff.procinfo.pid);
			retval |= __put_user((p->exit_code >> 8) & 0xff,
			           &info->stuff.procinfo.procdata.child.status);
			retval |= __put_user(p->utime, &info->stuff.procinfo.procdata.child.utime);
			retval |= __put_user(p->stime, &info->stuff.procinfo.procdata.child.stime);
			if (retval)
				goto end_waitsys;

			p->exit_code = 0;
			goto end_waitsys;

		case EXIT_ZOMBIE:
			current->signal->cutime += p->utime + p->signal->cutime;
			current->signal->cstime += p->stime + p->signal->cstime;
			if (ru != NULL)
				getrusage(p, RUSAGE_BOTH, ru);
			retval = __put_user(SIGCHLD, &info->sig);
			retval |= __put_user(1, &info->code);      /* CLD_EXITED */
			retval |= __put_user(p->pid, &info->stuff.procinfo.pid);
			retval |= __put_user((p->exit_code >> 8) & 0xff,
			           &info->stuff.procinfo.procdata.child.status);
			retval |= __put_user(p->utime,
			           &info->stuff.procinfo.procdata.child.utime);
			retval |= __put_user(p->stime,
			           &info->stuff.procinfo.procdata.child.stime);
			if (retval)
				return retval;

			if (p->real_parent != p->parent) {
				write_lock_irq(&tasklist_lock);
				remove_parent(p);
				p->parent = p->real_parent;
				add_parent(p);
				do_notify_parent(p, SIGCHLD);
				write_unlock_irq(&tasklist_lock);
			} else
				release_task(p);
			goto end_waitsys;
		default:
			continue;
		}
		tsk = next_thread(tsk);
	}
	read_unlock(&tasklist_lock);
	if (flag) {
		retval = 0;
		if (options & W_NOHANG)
			goto end_waitsys;
		retval = -ERESTARTSYS;
		if (signal_pending(current))
			goto end_waitsys;
		current->state = TASK_INTERRUPTIBLE;
		schedule();
		goto repeat;
	}
	retval = -ECHILD;
end_waitsys:
	current->state = TASK_RUNNING;
	remove_wait_queue(&current->signal->wait_chldexit, &wait);

	return retval;
}

struct irix5_context {
	u32 flags;
	u32 link;
	u32 sigmask[4];
	struct { u32 sp, size, flags; } stack;
	int regs[36];
	u32 fpregs[32];
	u32 fpcsr;
	u32 _unused0;
	u32 _unused1[47];
	u32 weird_graphics_thing;
};

asmlinkage int irix_getcontext(struct pt_regs *regs)
{
	int error, i, base = 0;
	struct irix5_context __user *ctx;
	unsigned long flags;

	if (regs->regs[2] == 1000)
		base = 1;
	ctx = (struct irix5_context __user *) regs->regs[base + 4];

#ifdef DEBUG_SIG
	printk("[%s:%d] irix_getcontext(%p)\n",
	       current->comm, current->pid, ctx);
#endif

	if (!access_ok(VERIFY_WRITE, ctx, sizeof(*ctx)));
		return -EFAULT;

	error = __put_user(current->thread.irix_oldctx, &ctx->link);

	error |= __copy_to_user(&ctx->sigmask, &current->blocked, sizeof(irix_sigset_t)) ? -EFAULT : 0;

	/* XXX Do sigstack stuff someday... */
	error |= __put_user(0, &ctx->stack.sp);
	error |= __put_user(0, &ctx->stack.size);
	error |= __put_user(0, &ctx->stack.flags);

	error |= __put_user(0, &ctx->weird_graphics_thing);
	error |= __put_user(0, &ctx->regs[0]);
	for (i = 1; i < 32; i++)
		error |= __put_user(regs->regs[i], &ctx->regs[i]);
	error |= __put_user(regs->lo, &ctx->regs[32]);
	error |= __put_user(regs->hi, &ctx->regs[33]);
	error |= __put_user(regs->cp0_cause, &ctx->regs[34]);
	error |= __put_user(regs->cp0_epc, &ctx->regs[35]);

	flags = 0x0f;
	if (!used_math()) {
		flags &= ~(0x08);
	} else {
		/* XXX wheee... */
		printk("Wheee, no code for saving IRIX FPU context yet.\n");
	}
	error |= __put_user(flags, &ctx->flags);

	return error;
}

asmlinkage void irix_setcontext(struct pt_regs *regs)
{
	struct irix5_context __user *ctx;
	int err, base = 0;
	u32 flags;

	if (regs->regs[2] == 1000)
		base = 1;
	ctx = (struct irix5_context __user *) regs->regs[base + 4];

#ifdef DEBUG_SIG
	printk("[%s:%d] irix_setcontext(%p)\n",
	       current->comm, current->pid, ctx);
#endif

	if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx)))
		goto segv_and_exit;

	err = __get_user(flags, &ctx->flags);
	if (flags & 0x02) {
		/* XXX sigstack garbage, todo... */
		printk("Wheee, cannot do sigstack stuff in setcontext\n");
	}

	if (flags & 0x04) {
		int i;

		/* XXX extra control block stuff... todo... */
		for (i = 1; i < 32; i++)
			err |= __get_user(regs->regs[i], &ctx->regs[i]);
		err |= __get_user(regs->lo, &ctx->regs[32]);
		err |= __get_user(regs->hi, &ctx->regs[33]);
		err |= __get_user(regs->cp0_epc, &ctx->regs[35]);
	}

	if (flags & 0x08)
		/* XXX fpu context, blah... */
		printk(KERN_ERR "Wheee, cannot restore FPU context yet...\n");

	err |= __get_user(current->thread.irix_oldctx, &ctx->link);
	if (err)
		goto segv_and_exit;

	/*
	 * Don't let your children do this ...
	 */
	__asm__ __volatile__(
		"move\t$29,%0\n\t"
		"j\tsyscall_exit"
		:/* no outputs */
		:"r" (&regs));
		/* Unreached */

segv_and_exit:
	force_sigsegv(SIGSEGV, current);
}

struct irix_sigstack {
	unsigned long sp;
	int status;
};

asmlinkage int irix_sigstack(struct irix_sigstack __user *new,
	struct irix_sigstack __user *old)
{
#ifdef DEBUG_SIG
	printk("[%s:%d] irix_sigstack(%p,%p)\n",
	       current->comm, current->pid, new, old);
#endif
	if (new) {
		if (!access_ok(VERIFY_READ, new, sizeof(*new)))
			return -EFAULT;
	}

	if (old) {
		if (!access_ok(VERIFY_WRITE, old, sizeof(*old)))
			return -EFAULT;
	}

	return 0;
}

struct irix_sigaltstack { unsigned long sp; int size; int status; };

asmlinkage int irix_sigaltstack(struct irix_sigaltstack __user *new,
				struct irix_sigaltstack __user *old)
{
#ifdef DEBUG_SIG
	printk("[%s:%d] irix_sigaltstack(%p,%p)\n",
	       current->comm, current->pid, new, old);
#endif
	if (new)
		if (!access_ok(VERIFY_READ, new, sizeof(*new)))
			return -EFAULT;

	if (old) {
		if (!access_ok(VERIFY_WRITE, old, sizeof(*old)))
			return -EFAULT;
	}

	return 0;
}

struct irix_procset {
	int cmd, ltype, lid, rtype, rid;
};

asmlinkage int irix_sigsendset(struct irix_procset __user *pset, int sig)
{
	if (!access_ok(VERIFY_READ, pset, sizeof(*pset)))
		return -EFAULT;
#ifdef DEBUG_SIG
	printk("[%s:%d] irix_sigsendset([%d,%d,%d,%d,%d],%d)\n",
	       current->comm, current->pid,
	       pset->cmd, pset->ltype, pset->lid, pset->rtype, pset->rid,
	       sig);
#endif
	return -EINVAL;
}