Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 241 insertions, 0 deletions

diff --git a/kernel/itimer.c b/kernel/itimer.c
new file mode 100644
index 000000000000..e9a40e947e07
--- /dev/null
+++ b/kernel/itimer.c
@@ -0,0 +1,241 @@
+/*
+ * linux/kernel/itimer.c
+ *
+ * Copyright (C) 1992 Darren Senn
+ */
+
+/* These are all the functions necessary to implement itimers */
+
+#include <linux/mm.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/syscalls.h>
+#include <linux/time.h>
+#include <linux/posix-timers.h>
+
+#include <asm/uaccess.h>
+
+static unsigned long it_real_value(struct signal_struct *sig)
+{
+	unsigned long val = 0;
+	if (timer_pending(&sig->real_timer)) {
+		val = sig->real_timer.expires - jiffies;
+
+		/* look out for negative/zero itimer.. */
+		if ((long) val <= 0)
+			val = 1;
+	}
+	return val;
+}
+
+int do_getitimer(int which, struct itimerval *value)
+{
+	struct task_struct *tsk = current;
+	unsigned long interval, val;
+	cputime_t cinterval, cval;
+
+	switch (which) {
+	case ITIMER_REAL:
+		spin_lock_irq(&tsk->sighand->siglock);
+		interval = tsk->signal->it_real_incr;
+		val = it_real_value(tsk->signal);
+		spin_unlock_irq(&tsk->sighand->siglock);
+		jiffies_to_timeval(val, &value->it_value);
+		jiffies_to_timeval(interval, &value->it_interval);
+		break;
+	case ITIMER_VIRTUAL:
+		read_lock(&tasklist_lock);
+		spin_lock_irq(&tsk->sighand->siglock);
+		cval = tsk->signal->it_virt_expires;
+		cinterval = tsk->signal->it_virt_incr;
+		if (!cputime_eq(cval, cputime_zero)) {
+			struct task_struct *t = tsk;
+			cputime_t utime = tsk->signal->utime;
+			do {
+				utime = cputime_add(utime, t->utime);
+				t = next_thread(t);
+			} while (t != tsk);
+			if (cputime_le(cval, utime)) { /* about to fire */
+				cval = jiffies_to_cputime(1);
+			} else {
+				cval = cputime_sub(cval, utime);
+			}
+		}
+		spin_unlock_irq(&tsk->sighand->siglock);
+		read_unlock(&tasklist_lock);
+		cputime_to_timeval(cval, &value->it_value);
+		cputime_to_timeval(cinterval, &value->it_interval);
+		break;
+	case ITIMER_PROF:
+		read_lock(&tasklist_lock);
+		spin_lock_irq(&tsk->sighand->siglock);
+		cval = tsk->signal->it_prof_expires;
+		cinterval = tsk->signal->it_prof_incr;
+		if (!cputime_eq(cval, cputime_zero)) {
+			struct task_struct *t = tsk;
+			cputime_t ptime = cputime_add(tsk->signal->utime,
+						      tsk->signal->stime);
+			do {
+				ptime = cputime_add(ptime,
+						    cputime_add(t->utime,
+								t->stime));
+				t = next_thread(t);
+			} while (t != tsk);
+			if (cputime_le(cval, ptime)) { /* about to fire */
+				cval = jiffies_to_cputime(1);
+			} else {
+				cval = cputime_sub(cval, ptime);
+			}
+		}
+		spin_unlock_irq(&tsk->sighand->siglock);
+		read_unlock(&tasklist_lock);
+		cputime_to_timeval(cval, &value->it_value);
+		cputime_to_timeval(cinterval, &value->it_interval);
+		break;
+	default:
+		return(-EINVAL);
+	}
+	return 0;
+}
+
+asmlinkage long sys_getitimer(int which, struct itimerval __user *value)
+{
+	int error = -EFAULT;
+	struct itimerval get_buffer;
+
+	if (value) {
+		error = do_getitimer(which, &get_buffer);
+		if (!error &&
+		    copy_to_user(value, &get_buffer, sizeof(get_buffer)))
+			error = -EFAULT;
+	}
+	return error;
+}
+
+/*
+ * Called with P->sighand->siglock held and P->signal->real_timer inactive.
+ * If interval is nonzero, arm the timer for interval ticks from now.
+ */
+static inline void it_real_arm(struct task_struct *p, unsigned long interval)
+{
+	p->signal->it_real_value = interval; /* XXX unnecessary field?? */
+	if (interval == 0)
+		return;
+	if (interval > (unsigned long) LONG_MAX)
+		interval = LONG_MAX;
+	p->signal->real_timer.expires = jiffies + interval;
+	add_timer(&p->signal->real_timer);
+}
+
+void it_real_fn(unsigned long __data)
+{
+	struct task_struct * p = (struct task_struct *) __data;
+
+	send_group_sig_info(SIGALRM, SEND_SIG_PRIV, p);
+
+	/*
+	 * Now restart the timer if necessary.  We don't need any locking
+	 * here because do_setitimer makes sure we have finished running
+	 * before it touches anything.
+	 */
+	it_real_arm(p, p->signal->it_real_incr);
+}
+
+int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
+{
+	struct task_struct *tsk = current;
+ 	unsigned long val, interval;
+	cputime_t cval, cinterval, nval, ninterval;
+
+	switch (which) {
+	case ITIMER_REAL:
+		spin_lock_irq(&tsk->sighand->siglock);
+		interval = tsk->signal->it_real_incr;
+		val = it_real_value(tsk->signal);
+		if (val)
+			del_timer_sync(&tsk->signal->real_timer);
+		tsk->signal->it_real_incr =
+			timeval_to_jiffies(&value->it_interval);
+		it_real_arm(tsk, timeval_to_jiffies(&value->it_value));
+		spin_unlock_irq(&tsk->sighand->siglock);
+		if (ovalue) {
+			jiffies_to_timeval(val, &ovalue->it_value);
+			jiffies_to_timeval(interval,
+					   &ovalue->it_interval);
+		}
+		break;
+	case ITIMER_VIRTUAL:
+		nval = timeval_to_cputime(&value->it_value);
+		ninterval = timeval_to_cputime(&value->it_interval);
+		read_lock(&tasklist_lock);
+		spin_lock_irq(&tsk->sighand->siglock);
+		cval = tsk->signal->it_virt_expires;
+		cinterval = tsk->signal->it_virt_incr;
+		if (!cputime_eq(cval, cputime_zero) ||
+		    !cputime_eq(nval, cputime_zero)) {
+			if (cputime_gt(nval, cputime_zero))
+				nval = cputime_add(nval,
+						   jiffies_to_cputime(1));
+			set_process_cpu_timer(tsk, CPUCLOCK_VIRT,
+					      &nval, &cval);
+		}
+		tsk->signal->it_virt_expires = nval;
+		tsk->signal->it_virt_incr = ninterval;
+		spin_unlock_irq(&tsk->sighand->siglock);
+		read_unlock(&tasklist_lock);
+		if (ovalue) {
+			cputime_to_timeval(cval, &ovalue->it_value);
+			cputime_to_timeval(cinterval, &ovalue->it_interval);
+		}
+		break;
+	case ITIMER_PROF:
+		nval = timeval_to_cputime(&value->it_value);
+		ninterval = timeval_to_cputime(&value->it_interval);
+		read_lock(&tasklist_lock);
+		spin_lock_irq(&tsk->sighand->siglock);
+		cval = tsk->signal->it_prof_expires;
+		cinterval = tsk->signal->it_prof_incr;
+		if (!cputime_eq(cval, cputime_zero) ||
+		    !cputime_eq(nval, cputime_zero)) {
+			if (cputime_gt(nval, cputime_zero))
+				nval = cputime_add(nval,
+						   jiffies_to_cputime(1));
+			set_process_cpu_timer(tsk, CPUCLOCK_PROF,
+					      &nval, &cval);
+		}
+		tsk->signal->it_prof_expires = nval;
+		tsk->signal->it_prof_incr = ninterval;
+		spin_unlock_irq(&tsk->sighand->siglock);
+		read_unlock(&tasklist_lock);
+		if (ovalue) {
+			cputime_to_timeval(cval, &ovalue->it_value);
+			cputime_to_timeval(cinterval, &ovalue->it_interval);
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+asmlinkage long sys_setitimer(int which,
+			      struct itimerval __user *value,
+			      struct itimerval __user *ovalue)
+{
+	struct itimerval set_buffer, get_buffer;
+	int error;
+
+	if (value) {
+		if(copy_from_user(&set_buffer, value, sizeof(set_buffer)))
+			return -EFAULT;
+	} else
+		memset((char *) &set_buffer, 0, sizeof(set_buffer));
+
+	error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
+	if (error || !ovalue)
+		return error;
+
+	if (copy_to_user(ovalue, &get_buffer, sizeof(get_buffer)))
+		return -EFAULT; 
+	return 0;
+}