Beispiel #1
0
struct task_struct *kthread_create(int (*threadfn)(void *data),
				   void *data,
				   const char namefmt[],
				   ...)
{
	struct kthread_create_info create;
	DECLARE_WORK(work, keventd_create_kthread, &create);

	create.threadfn = threadfn;
	create.data = data;
	init_completion(&create.started);
	init_completion(&create.done);

	/*
	 * The workqueue needs to start up first:
	 */
	if (!helper_wq)
		work.func(work.data);
	else {
		queue_work(helper_wq, &work);
		wait_for_completion(&create.done);
	}
	if (!IS_ERR(create.result)) {
		va_list args;
		va_start(args, namefmt);
		vsnprintf(create.result->comm, sizeof(create.result->comm),
			  namefmt, args);
		va_end(args);
	}

	return create.result;
}
Beispiel #2
0
/**
 * call_usermodehelper_keys - start a usermode application
 * @path: pathname for the application
 * @argv: null-terminated argument list
 * @envp: null-terminated environment list
 * @session_keyring: session keyring for process (NULL for an empty keyring)
 * @wait: wait for the application to finish and return status.
 *
 * Runs a user-space application.  The application is started
 * asynchronously if wait is not set, and runs as a child of keventd.
 * (ie. it runs with full root capabilities).
 *
 * Must be called from process context.  Returns a negative error code
 * if program was not execed successfully, or 0.
 */
int call_usermodehelper_keys(char *path, char **argv, char **envp,
			     struct key *session_keyring, int wait)
{
	DECLARE_COMPLETION(done);
	struct subprocess_info sub_info = {
		.complete	= &done,
		.path		= path,
		.argv		= argv,
		.envp		= envp,
		.ring		= session_keyring,
		.wait		= wait,
		.retval		= 0,
	};

	DECLARE_WORK(work, __call_usermodehelper, &sub_info);

	OSA_REGISTER_SPINLOCK(&done.wait.lock, "wait_queue_head_t->lock", 23);

	if (!khelper_wq)
		return -EBUSY;

	if (path[0] == '\0')
		return 0;

	queue_work(khelper_wq, &work);
	wait_for_completion(&done);
	return sub_info.retval;
}
EXPORT_SYMBOL(call_usermodehelper_keys);

void __init usermodehelper_init(void)
{
	khelper_wq = create_singlethread_workqueue("khelper");
	BUG_ON(!khelper_wq);
}
Beispiel #3
0
/**
 * kthread_create - create a kthread.
 * @threadfn: the function to run until signal_pending(current).
 * @data: data ptr for @threadfn.
 * @namefmt: printf-style name for the thread.
 *
 * Description: This helper function creates and names a kernel
 * thread.  The thread will be stopped: use wake_up_process() to start
 * it.  See also kthread_run(), kthread_create_on_cpu().
 *
 * When woken, the thread will run @threadfn() with @data as its
 * argument. @threadfn can either call do_exit() directly if it is a
 * standalone thread for which noone will call kthread_stop(), or
 * return when 'kthread_should_stop()' is true (which means
 * kthread_stop() has been called).  The return value should be zero
 * or a negative error number; it will be passed to kthread_stop().
 *
 * Returns a task_struct or ERR_PTR(-ENOMEM).
 */
struct task_struct *kthread_create(int (*threadfn)(void *data),
				   void *data,
				   const char namefmt[],
				   ...)
{
	struct kthread_create_info create;
	DECLARE_WORK(work, keventd_create_kthread, &create);

	create.threadfn = threadfn;
	create.data = data;
	init_completion(&create.started);
	init_completion(&create.done);

	/*
	 * The workqueue needs to start up first:
	 */
	if (!helper_wq)
		work.func(work.data);
	else {
		queue_work(helper_wq, &work);
		wait_for_completion(&create.done);
	}
	if (!IS_ERR(create.result)) {
		va_list args;
		va_start(args, namefmt);
		vsnprintf(create.result->comm, sizeof(create.result->comm),
			  namefmt, args);
		va_end(args);
#ifdef CONFIG_TIVO
    int  i;
    int bFound = 0;
    for (i=0; i<sizeof(s_tvKthreadInfoTable)/sizeof(TvKthreadInfo); i++)
    {
        if (!strcmp(s_tvKthreadInfoTable[i].name, create.result->comm))
        {
            if (s_tvKthreadInfoTable[i].policy != -1)
            {
                create.result->policy = s_tvKthreadInfoTable[i].policy;
                create.result->rt_priority = s_tvKthreadInfoTable[i].rt_priority;
            }
            bFound = 1;
            break;
        }
    }

    //    if (!bFound)
    //    {
    //        printk("--- New thread %s is launched with default priority\n", create.result->comm);
    //    }

    
#endif
	}

	return create.result;
}
Beispiel #4
0
static int __devinit
do_boot_cpu (int sapicid, int cpu)
{
	int timeout;
	struct create_idle c_idle = {
		.cpu	= cpu,
		.done	= COMPLETION_INITIALIZER(c_idle.done),
	};
	DECLARE_WORK(work, do_fork_idle, &c_idle);
	/*
	 * We can't use kernel_thread since we must avoid to reschedule the child.
	 */
	if (!keventd_up() || current_is_keventd())
		work.func(work.data);
	else {
		schedule_work(&work);
		wait_for_completion(&c_idle.done);
	}

	if (IS_ERR(c_idle.idle))
		panic("failed fork for CPU %d", cpu);
	task_for_booting_cpu = c_idle.idle;

	Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);

	platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);

	/*
	 * Wait 10s total for the AP to start
	 */
	Dprintk("Waiting on callin_map ...");
	for (timeout = 0; timeout < 100000; timeout++) {
		if (cpu_isset(cpu, cpu_callin_map))
			break;  /* It has booted */
		udelay(100);
	}
	Dprintk("\n");

	if (!cpu_isset(cpu, cpu_callin_map)) {
		printk(KERN_ERR "Processor 0x%x/0x%x is stuck.\n", cpu, sapicid);
		ia64_cpu_to_sapicid[cpu] = -1;
		cpu_clear(cpu, cpu_online_map);  /* was set in smp_callin() */
		return -EINVAL;
	}
	return 0;
}

static int __init
decay (char *str)
{
	int ticks;
	get_option (&str, &ticks);
	return 1;
}
static void __exit producer_mod_cleanup(void)
{
	DECLARE_WORK(kill, stop_exec);
	continue_exec = 0;

	printk(KERN_INFO "--- %s: unloading...\n", mod_name);
	printk(KERN_INFO "--- %s: cancel remaining work\n", mod_name);
	cancel_delayed_work(&work);

	printk(KERN_INFO "--- %s: queue kill request\n", mod_name);
	queue_work(wqs, &kill);
	
	printk(KERN_INFO "--- %s: waiting for work to finish...\n", mod_name);
	cancel_delayed_work_sync(&work);
	cancel_work_sync(&kill);

	destroy_workqueue(wqs);
	printk(KERN_INFO "--- %s: unloading complete!\n", mod_name);
}
Beispiel #6
0
/*
 * This is the task which runs the usermode application
 */
static int ____call_usermodehelper(void *data)
{
	struct subprocess_info *sub_info = data;
	int retval;

	/* Install input pipe when needed */
	if (sub_info->stdin) {
		struct files_struct *f = current->files;
		struct fdtable *fdt;
		/* no races because files should be private here */
		sys_close(0);
		fd_install(0, sub_info->stdin);
		spin_lock(&f->file_lock);
		fdt = files_fdtable(f);
		FD_SET(0, fdt->open_fds);
		FD_CLR(0, fdt->close_on_exec);
		spin_unlock(&f->file_lock);

		/* and disallow core files too */
		current->signal->rlim[RLIMIT_CORE] = (struct rlimit){0, 0};
	}
 

	/* We can run anywhere, unlike our parent keventd(). */
	set_cpus_allowed(current, CPU_MASK_ALL);

	retval = __exec_usermodehelper(sub_info->path,
			sub_info->argv, sub_info->envp, sub_info->ring);

	/* Exec failed? */
	sub_info->retval = retval;
	do_exit(0);
}

/* Keventd can't block, but this (a child) can. */
static int wait_for_helper(void *data)
{
	struct subprocess_info *sub_info = data;
	pid_t pid;
	struct k_sigaction sa;

	/* Install a handler: if SIGCLD isn't handled sys_wait4 won't
	 * populate the status, but will return -ECHILD. */
	sa.sa.sa_handler = SIG_IGN;
	sa.sa.sa_flags = 0;
	siginitset(&sa.sa.sa_mask, sigmask(SIGCHLD));
	do_sigaction(SIGCHLD, &sa, NULL);
	allow_signal(SIGCHLD);

	pid = kernel_thread(____call_usermodehelper, sub_info, SIGCHLD);
	if (pid < 0) {
		sub_info->retval = pid;
	} else {
		/*
		 * Normally it is bogus to call wait4() from in-kernel because
		 * wait4() wants to write the exit code to a userspace address.
		 * But wait_for_helper() always runs as keventd, and put_user()
		 * to a kernel address works OK for kernel threads, due to their
		 * having an mm_segment_t which spans the entire address space.
		 *
		 * Thus the __user pointer cast is valid here.
		 */
		sys_wait4(pid, (int __user *) &sub_info->retval, 0, NULL);
	}

	complete(sub_info->complete);
	return 0;
}

/* This is run by khelper thread  */
static void __call_usermodehelper(void *data)
{
	struct subprocess_info *sub_info = data;
	pid_t pid;
	int wait = sub_info->wait;

	/* CLONE_VFORK: wait until the usermode helper has execve'd
	 * successfully We need the data structures to stay around
	 * until that is done.  */
	if (wait)
		pid = kernel_thread(wait_for_helper, sub_info,
				    CLONE_FS | CLONE_FILES | SIGCHLD);
	else
		pid = kernel_thread(____call_usermodehelper, sub_info,
				    CLONE_VFORK | SIGCHLD);

	if (pid < 0) {
		sub_info->retval = pid;
		complete(sub_info->complete);
	} else if (!wait)
		complete(sub_info->complete);
}

/**
 * call_usermodehelper_keys - start a usermode application
 * @path: pathname for the application
 * @argv: null-terminated argument list
 * @envp: null-terminated environment list
 * @session_keyring: session keyring for process (NULL for an empty keyring)
 * @wait: wait for the application to finish and return status.
 *
 * Runs a user-space application.  The application is started
 * asynchronously if wait is not set, and runs as a child of keventd.
 * (ie. it runs with full root capabilities).
 *
 * Must be called from process context.  Returns a negative error code
 * if program was not execed successfully, or 0.
 */
int call_usermodehelper_keys(char *path, char **argv, char **envp,
			     struct key *session_keyring, int wait)
{
	DECLARE_COMPLETION_ONSTACK(done);
	struct subprocess_info sub_info = {
		.complete	= &done,
		.path		= path,
		.argv		= argv,
		.envp		= envp,
		.ring		= session_keyring,
		.wait		= wait,
		.retval		= 0,
	};
	DECLARE_WORK(work, __call_usermodehelper, &sub_info);

	if (!khelper_wq)
		return -EBUSY;

	if (path[0] == '\0')
		return 0;

	queue_work(khelper_wq, &work);
	wait_for_completion(&done);
	return sub_info.retval;
}
EXPORT_SYMBOL(call_usermodehelper_keys);

int call_usermodehelper_pipe(char *path, char **argv, char **envp,
			     struct file **filp)
{
	DECLARE_COMPLETION(done);
	struct subprocess_info sub_info = {
		.complete	= &done,
		.path		= path,
		.argv		= argv,
		.envp		= envp,
		.retval		= 0,
	};
	struct file *f;
	DECLARE_WORK(work, __call_usermodehelper, &sub_info);

	if (!khelper_wq)
		return -EBUSY;

	if (path[0] == '\0')
		return 0;

	f = create_write_pipe();
	if (!f)
		return -ENOMEM;
	*filp = f;

	f = create_read_pipe(f);
	if (!f) {
		free_write_pipe(*filp);
		return -ENOMEM;
	}
	sub_info.stdin = f;

	queue_work(khelper_wq, &work);
	wait_for_completion(&done);
	return sub_info.retval;
}
EXPORT_SYMBOL(call_usermodehelper_pipe);

void __init usermodehelper_init(void)
{
	khelper_wq = create_singlethread_workqueue("khelper");
	BUG_ON(!khelper_wq);
}