Add initial AIO/LIO kernel thread support files. This is preliminary, and

further features will be added.

1 files changed, 168 insertions, 0 deletions

diff --git a/sys/kern/kern_threads.c b/sys/kern/kern_threads.c
new file mode 100644
index 0000000..30e15c9
--- /dev/null
+++ b/sys/kern/kern_threads.c
@@ -0,0 +1,168 @@
+/*
+ *
+ * Portions of this code was derived from the file kern_fork.c and as such
+ * is subject to the copyrights below.
+ *
+ * Copyright (c) 1982, 1986, 1989, 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * Copyright (c) 1996 Douglas Santry
+ *
+ * This code is subject to the beer copyright.  If I chance to meet you in a
+ * bar and this code helped you in some way, you owe me a beer.  Only
+ * in Germany will I accept domestic beer.  This code may or may not work
+ * and I certainly make no claims as to its fitness for *any* purpose.
+ * 
+ * $Id$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/filedesc.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/proc.h>
+#include <sys/resourcevar.h>
+#include <sys/vnode.h>
+#include <sys/file.h>
+#include <sys/acct.h>
+#include <sys/ktrace.h>
+#include <sys/sysproto.h>
+#include <sys/unistd.h>
+
+#include <vm/vm.h>
+
+#include <machine/cpu.h>
+
+/*
+ * Low level support for sleep/wakeup paradigm
+ * If a timeout is specified:
+ *	returns 0 if wakeup
+ *	returns EAGAIN if timed out
+ *	returns EINVAL if error
+ *
+ * If a timeout is not specified:
+ *
+ *	returns time waiting in ticks.
+ */
+int
+thr_sleep(struct proc *p, struct thr_sleep_args *uap, int *retval) {
+	int sleepStart;
+	long long sleeptime;
+	int sleepclocks;
+	struct timespec ts;
+	int error;
+
+	sleepclocks = 0;
+	if (uap->timeout != 0) {
+		/*
+		 * Get timespec struct
+		 */
+		if (error = copyin((caddr_t) uap->timeout, (caddr_t) &ts, sizeof ts)) {
+			p->p_wakeup = 0;
+			return error;
+		}
+		sleeptime = (long long) (hz * ts.tv_nsec);
+		sleeptime /= 1000000000LL;
+		sleeptime += ts.tv_sec * hz;
+		sleepclocks = sleeptime;
+		if (sleepclocks != sleeptime) {
+			p->p_wakeup = 0;
+			retval[0] = EINVAL;
+			return 0;
+		}
+		if (sleepclocks == 0)
+			sleepclocks = 1;
+	}
+
+	retval[0] = 0;
+	if (p->p_wakeup == 0) {
+		sleepStart = ticks;
+		p->p_flag |= P_SINTR;
+		error = tsleep(p, PUSER, "thrslp", sleepclocks);
+		p->p_flag &= ~P_SINTR;
+		if (error == EWOULDBLOCK) {
+			p->p_wakeup = 0;
+			retval[0] = EAGAIN;
+			return 0;
+		}
+		if (uap->timeout == 0)
+			retval[0] = ticks - sleepStart;
+	}
+	p->p_wakeup = 0;
+	return (0);
+}
+
+int
+thr_wakeup(struct proc *p, struct thr_wakeup_args *uap, int *retval) {
+	struct proc *pSlave = p->p_leader;
+
+	while(pSlave && (pSlave->p_pid != uap->pid))
+		pSlave = pSlave->p_peers;
+
+	if(pSlave == 0) {
+		retval[0] = ESRCH;
+		return(0);
+	}
+
+	pSlave->p_wakeup++;
+	if((pSlave->p_stat == SSLEEP) && (pSlave->p_wchan == pSlave)) {
+		wakeup(pSlave);
+		return(0);
+	}
+
+	retval[0] = EAGAIN;
+	return 0;
+}
+
+/*
+ * General purpose yield system call
+ */
+int
+yield(struct proc *p, struct yield_args *uap, int *retval) {
+	int s;
+
+	retval[0] = 0;
+
+	s = splhigh();
+	p->p_priority = MAXPRI;
+	setrunqueue(p);
+	mi_switch();
+	splx(s);
+
+	return(0);
+}
+