smb_thread.c revision b819cea2f73f98c5662230cc9affc8cc84f77fcf
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright 2013 Nexenta Systems, Inc. All rights reserved.
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/tzfile.h>
#include <sys/atomic.h>
#include <sys/kidmap.h>
#include <sys/time.h>
#include <sys/spl.h>
#include <sys/random.h>
#include <smbsrv/smb_kproto.h>
#include <smbsrv/smb_fsops.h>
#include <smbsrv/smbinfo.h>
#include <smbsrv/smb_xdr.h>
#include <smbsrv/smb_vops.h>
#include <smbsrv/smb_idmap.h>
#include <sys/sid.h>
#include <sys/priv_names.h>
#ifdef _FAKE_KERNEL
#define THR_TO_DID(t) ((kt_did_t)(uintptr_t)t)
#else
#define THR_TO_DID(t) (t->t_did)
#endif
static boolean_t smb_thread_continue_timedwait_locked(smb_thread_t *, int);
/*
* smb_thread_entry_point
*
* Common entry point for all the threads created through smb_thread_start.
* The state of the thread is set to "running" at the beginning and moved to
* "exiting" just before calling thread_exit(). The condition variable is
* also signaled.
*/
static void
smb_thread_entry_point(
smb_thread_t *thread)
{
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
ASSERT(thread->sth_state == SMB_THREAD_STATE_STARTING);
if (!thread->sth_kill) {
thread->sth_state = SMB_THREAD_STATE_RUNNING;
cv_signal(&thread->sth_cv);
mutex_exit(&thread->sth_mtx);
/* Run the real thread entry point. */
thread->sth_ep(thread, thread->sth_ep_arg);
mutex_enter(&thread->sth_mtx);
}
/*
* It's tempting to clear sth_did here too, but don't.
* That's needed in thread_join().
*/
thread->sth_th = NULL;
thread->sth_state = SMB_THREAD_STATE_EXITING;
cv_broadcast(&thread->sth_cv);
mutex_exit(&thread->sth_mtx);
zthread_exit();
}
/*
* smb_thread_init
*/
void
smb_thread_init(
smb_thread_t *thread,
char *name,
smb_thread_ep_t ep,
void *ep_arg,
pri_t pri)
{
ASSERT(thread->sth_magic != SMB_THREAD_MAGIC);
bzero(thread, sizeof (*thread));
(void) strlcpy(thread->sth_name, name, sizeof (thread->sth_name));
thread->sth_ep = ep;
thread->sth_ep_arg = ep_arg;
thread->sth_state = SMB_THREAD_STATE_EXITED;
thread->sth_pri = pri;
mutex_init(&thread->sth_mtx, NULL, MUTEX_DEFAULT, NULL);
cv_init(&thread->sth_cv, NULL, CV_DEFAULT, NULL);
thread->sth_magic = SMB_THREAD_MAGIC;
}
/*
* smb_thread_destroy
*/
void
smb_thread_destroy(
smb_thread_t *thread)
{
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
ASSERT(thread->sth_state == SMB_THREAD_STATE_EXITED);
thread->sth_magic = 0;
mutex_destroy(&thread->sth_mtx);
cv_destroy(&thread->sth_cv);
}
/*
* smb_thread_start
*
* This function starts a thread with the parameters provided. It waits until
* the state of the thread has been moved to running.
*/
/*ARGSUSED*/
int
smb_thread_start(
smb_thread_t *thread)
{
int rc = 0;
kthread_t *tmpthread;
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
switch (thread->sth_state) {
case SMB_THREAD_STATE_EXITED:
thread->sth_state = SMB_THREAD_STATE_STARTING;
mutex_exit(&thread->sth_mtx);
tmpthread = zthread_create(NULL, 0, smb_thread_entry_point,
thread, 0, thread->sth_pri);
ASSERT(tmpthread != NULL);
mutex_enter(&thread->sth_mtx);
thread->sth_th = tmpthread;
thread->sth_did = THR_TO_DID(tmpthread);
while (thread->sth_state == SMB_THREAD_STATE_STARTING)
cv_wait(&thread->sth_cv, &thread->sth_mtx);
if (thread->sth_state != SMB_THREAD_STATE_RUNNING)
rc = -1;
break;
default:
ASSERT(0);
rc = -1;
break;
}
mutex_exit(&thread->sth_mtx);
return (rc);
}
/*
* smb_thread_stop
*
* This function signals a thread to kill itself and waits until the "exiting"
* state has been reached.
*/
void
smb_thread_stop(smb_thread_t *thread)
{
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
switch (thread->sth_state) {
case SMB_THREAD_STATE_RUNNING:
case SMB_THREAD_STATE_STARTING:
if (!thread->sth_kill) {
thread->sth_kill = B_TRUE;
cv_broadcast(&thread->sth_cv);
while (thread->sth_state != SMB_THREAD_STATE_EXITING)
cv_wait(&thread->sth_cv, &thread->sth_mtx);
mutex_exit(&thread->sth_mtx);
thread_join(thread->sth_did);
mutex_enter(&thread->sth_mtx);
thread->sth_state = SMB_THREAD_STATE_EXITED;
thread->sth_did = 0;
thread->sth_kill = B_FALSE;
cv_broadcast(&thread->sth_cv);
break;
}
/* FALLTHROUGH */
case SMB_THREAD_STATE_EXITING:
if (thread->sth_kill) {
while (thread->sth_state != SMB_THREAD_STATE_EXITED)
cv_wait(&thread->sth_cv, &thread->sth_mtx);
} else {
thread->sth_state = SMB_THREAD_STATE_EXITED;
thread->sth_did = 0;
}
break;
case SMB_THREAD_STATE_EXITED:
break;
default:
ASSERT(0);
break;
}
mutex_exit(&thread->sth_mtx);
}
/*
* smb_thread_signal
*
* This function signals a thread.
*/
void
smb_thread_signal(smb_thread_t *thread)
{
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
switch (thread->sth_state) {
case SMB_THREAD_STATE_RUNNING:
cv_signal(&thread->sth_cv);
break;
default:
break;
}
mutex_exit(&thread->sth_mtx);
}
boolean_t
smb_thread_continue(smb_thread_t *thread)
{
boolean_t result;
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
result = smb_thread_continue_timedwait_locked(thread, 0);
mutex_exit(&thread->sth_mtx);
return (result);
}
boolean_t
smb_thread_continue_nowait(smb_thread_t *thread)
{
boolean_t result;
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
/*
* Setting ticks=-1 requests a non-blocking check. We will
* still block if the thread is in "suspend" state.
*/
result = smb_thread_continue_timedwait_locked(thread, -1);
mutex_exit(&thread->sth_mtx);
return (result);
}
boolean_t
smb_thread_continue_timedwait(smb_thread_t *thread, int seconds)
{
boolean_t result;
ASSERT(thread->sth_magic == SMB_THREAD_MAGIC);
mutex_enter(&thread->sth_mtx);
result = smb_thread_continue_timedwait_locked(thread,
SEC_TO_TICK(seconds));
mutex_exit(&thread->sth_mtx);
return (result);
}
/*
* smb_thread_continue_timedwait_locked
*
* Internal only. Ticks==-1 means don't block, Ticks == 0 means wait
* indefinitely
*/
static boolean_t
smb_thread_continue_timedwait_locked(smb_thread_t *thread, int ticks)
{
boolean_t result;
/* -1 means don't block */
if (ticks != -1 && !thread->sth_kill) {
if (ticks == 0) {
cv_wait(&thread->sth_cv, &thread->sth_mtx);
} else {
(void) cv_reltimedwait(&thread->sth_cv,
&thread->sth_mtx, (clock_t)ticks, TR_CLOCK_TICK);
}
}
result = (thread->sth_kill == 0);
return (result);
}