C++ (Cpp) XENBUS_IS_ERR_READ示例

示例#1

文件： manage.c 项目： AkyZero/wrapfs-latest

static void shutdown_handler(struct xenbus_watch *watch,
			     const char **vec, unsigned int len)
{
	char *str;
	struct xenbus_transaction xbt;
	int err;
	static struct shutdown_handler handlers[] = {
		{ "poweroff",	do_poweroff },
		{ "halt",	do_poweroff },
		{ "reboot",	do_reboot   },
#ifdef CONFIG_HIBERNATE_CALLBACKS
		{ "suspend",	do_suspend  },
#endif
		{NULL, NULL},
	};
	static struct shutdown_handler *handler;

	if (shutting_down != SHUTDOWN_INVALID)
		return;

 again:
	err = xenbus_transaction_start(&xbt);
	if (err)
		return;

	str = (char *)xenbus_read(xbt, "control", "shutdown", NULL);
	/* Ignore read errors and empty reads. */
	if (XENBUS_IS_ERR_READ(str)) {
		xenbus_transaction_end(xbt, 1);
		return;
	}

	for (handler = &handlers[0]; handler->command; handler++) {
		if (strcmp(str, handler->command) == 0)
			break;
	}

	/* Only acknowledge commands which we are prepared to handle. */
	if (handler->cb)
		xenbus_write(xbt, "control", "shutdown", "");

	err = xenbus_transaction_end(xbt, 0);
	if (err == -EAGAIN) {
		kfree(str);
		goto again;
	}

	if (handler->cb) {
		handler->cb();
	} else {
		pr_info("Ignoring shutdown request: %s\n", str);
		shutting_down = SHUTDOWN_INVALID;
	}

	kfree(str);
}

示例#2

文件： reboot.c 项目： Jinjian0609/UVP-Tools

static void shutdown_handler(struct xenbus_watch *watch,
			     const char **vec, unsigned int len)
{
	extern void ctrl_alt_del(void);
	char *str;
	struct xenbus_transaction xbt;
	int err, new_state = SHUTDOWN_INVALID;

	if ((shutting_down != SHUTDOWN_INVALID) &&
	    (shutting_down != SHUTDOWN_RESUMING))
		return;

 again:
	err = xenbus_transaction_start(&xbt);
	if (err)
		return;

	str = (char *)xenbus_read(xbt, "control", "shutdown", NULL);
	/* Ignore read errors and empty reads. */
	if (XENBUS_IS_ERR_READ(str)) {
		xenbus_transaction_end(xbt, 1);
		return;
	}

  /*将其清空后，如果热迁移时suspend失败则会导致迁移挂死，去掉后suspend失败后则会迁移超时*/
	//xenbus_write(xbt, "control", "shutdown", "");

	err = xenbus_transaction_end(xbt, 0);
	if (err == -EAGAIN) {
		kfree(str);
		goto again;
	}
    
    printk(KERN_WARNING "%s(%d): receive shutdown request %s\n", __FUNCTION__, __LINE__, str);
    
	if (strcmp(str, "poweroff") == 0)
		new_state = SHUTDOWN_POWEROFF;
	else if (strcmp(str, "reboot") == 0)
		ctrl_alt_del();
	else if (strcmp(str, "suspend") == 0)
		new_state = SHUTDOWN_SUSPEND;
	else if (strcmp(str, "halt") == 0)
		new_state = SHUTDOWN_HALT;
	else
		printk("Ignoring shutdown request: %s\n", str);

	switch_shutdown_state(new_state);

	kfree(str);
}

示例#3

static void shutdown_handler(struct xenbus_watch *watch,
			     const char **vec, unsigned int len)
{
	extern void ctrl_alt_del(void);
	char *str;
	struct xenbus_transaction xbt;
	int err;

	if (shutting_down != SHUTDOWN_INVALID)
		return;

 again:
	err = xenbus_transaction_start(&xbt);
	if (err)
		return;
	str = (char *)xenbus_read(xbt, "control", "shutdown", NULL);
	/* Ignore read errors and empty reads. */
	if (XENBUS_IS_ERR_READ(str)) {
		xenbus_transaction_end(xbt, 1);
		return;
	}

	xenbus_write(xbt, "control", "shutdown", "");

	err = xenbus_transaction_end(xbt, 0);
	if (err == -EAGAIN) {
		kfree(str);
		goto again;
	}

	if (strcmp(str, "poweroff") == 0)
		shutting_down = SHUTDOWN_POWEROFF;
	else if (strcmp(str, "reboot") == 0)
		ctrl_alt_del();
	else if (strcmp(str, "suspend") == 0)
		shutting_down = SHUTDOWN_SUSPEND;
	else if (strcmp(str, "halt") == 0)
		shutting_down = SHUTDOWN_HALT;
	else {
		printk("Ignoring shutdown request: %s\n", str);
		shutting_down = SHUTDOWN_INVALID;
	}

	if (shutting_down != SHUTDOWN_INVALID)
		schedule_work(&shutdown_work);

	kfree(str);
}

示例#4

static void shutdown_handler(struct xenbus_watch *watch,
                             const char **vec, unsigned int len)
{
    char *str;
    struct xenbus_transaction xbt;
    int err;

    if (shutting_down != SHUTDOWN_INVALID)
        return;

again:
    err = xenbus_transaction_start(&xbt);
    if (err)
        return;

    str = (char *)xenbus_read(xbt, "control", "shutdown", NULL);
    /* Ignore read errors and empty reads. */
    if (XENBUS_IS_ERR_READ(str)) {
        xenbus_transaction_end(xbt, 1);
        return;
    }

    xenbus_write(xbt, "control", "shutdown", "");

    err = xenbus_transaction_end(xbt, 0);
    if (err == -EAGAIN) {
        kfree(str);
        goto again;
    }

    if (strcmp(str, "poweroff") == 0 ||
            strcmp(str, "halt") == 0) {
        shutting_down = SHUTDOWN_POWEROFF;
        orderly_poweroff(false);
    } else if (strcmp(str, "reboot") == 0) {
        shutting_down = SHUTDOWN_POWEROFF; /* ? */
        ctrl_alt_del();
#ifdef CONFIG_PM_SLEEP
    } else if (strcmp(str, "suspend") == 0) {
        do_suspend();
#endif
    } else {
        printk(KERN_INFO "Ignoring shutdown request: %s\n", str);
        shutting_down = SHUTDOWN_INVALID;
    }

    kfree(str);
}

示例#5

文件： manage.c 项目： mdamt/linux

static void shutdown_handler(struct xenbus_watch *watch,
			     const char *path, const char *token)
{
	char *str;
	struct xenbus_transaction xbt;
	int err;
	int idx;

	if (shutting_down != SHUTDOWN_INVALID)
		return;

 again:
	err = xenbus_transaction_start(&xbt);
	if (err)
		return;

	str = (char *)xenbus_read(xbt, "control", "shutdown", NULL);
	/* Ignore read errors and empty reads. */
	if (XENBUS_IS_ERR_READ(str)) {
		xenbus_transaction_end(xbt, 1);
		return;
	}

	for (idx = 0; idx < ARRAY_SIZE(shutdown_handlers); idx++) {
		if (strcmp(str, shutdown_handlers[idx].command) == 0)
			break;
	}

	/* Only acknowledge commands which we are prepared to handle. */
	if (idx < ARRAY_SIZE(shutdown_handlers))
		xenbus_write(xbt, "control", "shutdown", "");

	err = xenbus_transaction_end(xbt, 0);
	if (err == -EAGAIN) {
		kfree(str);
		goto again;
	}

	if (idx < ARRAY_SIZE(shutdown_handlers)) {
		shutdown_handlers[idx].cb();
	} else {
		pr_info("Ignoring shutdown request: %s\n", str);
		shutting_down = SHUTDOWN_INVALID;
	}

	kfree(str);
}