Ejemplos de check_device_area en C++ (Cpp)

Ejemplo n.º 1

Archivo: dm-table.c Proyecto: laitianli/kernel-analyze_linux-2.6.18

/**ltl
 * 功能: 将目标设备加入到列表中
 * 参数: t	->映射表
 *		ti	->映射目标
 *		path	->映射目标<major:minor>
 * 		start-> 映射目标相对低层设备的起始偏移量(类似磁盘分区的起始地址)
 *		len	-> 此目标设备在dm设备的长度
 *		mode	-> rw
 *		result-> 底层设备对象
 * 返回值:
 * 说明:
 */
static int __table_get_device(struct dm_table *t, struct dm_target *ti,
			      const char *path, sector_t start, sector_t len,
			      int mode, struct dm_dev **result)
{
	int r;
	dev_t dev;
	struct dm_dev *dd;
	unsigned int major, minor;

	BUG_ON(!t);
	/* 获取主设备号和次设备号 */
	if (sscanf(path, "%u:%u", &major, &minor) == 2) {
		/* Extract the major/minor numbers */
		dev = MKDEV(major, minor);
		if (MAJOR(dev) != major || MINOR(dev) != minor)
			return -EOVERFLOW;
	} else {
		/* convert the path to a device */
		if ((r = lookup_device(path, &dev))) /* 根据设备路径/dev/sdb获取<major:minor> */
			return r;
	}
	/* 在列表中查找映射目标 */
	dd = find_device(&t->devices, dev);
	if (!dd) {
		dd = kmalloc(sizeof(*dd), GFP_KERNEL);
		if (!dd)
			return -ENOMEM;

		dd->mode = mode;
		dd->bdev = NULL;
		/* 打开设备 */
		if ((r = open_dev(dd, dev, t->md))) {
			kfree(dd);
			return r;
		}

		format_dev_t(dd->name, dev); /* 主设备号次设备号 */

		atomic_set(&dd->count, 0);
		/* 将目标设备插入到映射表中 */
		list_add(&dd->list, &t->devices);

	} else if (dd->mode != (mode | dd->mode)) {
		r = upgrade_mode(dd, mode, t->md);
		if (r)
			return r;
	}
	atomic_inc(&dd->count);
	/* 检查区域是否超过设备 */
	if (!check_device_area(dd, start, len)) {
		DMWARN("device %s too small for target", path);
		dm_put_device(ti, dd);
		return -EINVAL;
	}

	*result = dd;

	return 0;
}

Ejemplo n.º 2

Archivo: dm-table.c Proyecto: iPodLinux/linux-2.6.7-ipod

/*
 * Add a device to the list, or just increment the usage count if
 * it's already present.
 */
static int __table_get_device(struct dm_table *t, struct dm_target *ti,
			      const char *path, sector_t start, sector_t len,
			      int mode, struct dm_dev **result)
{
	int r;
	dev_t dev;
	struct dm_dev *dd;
	unsigned int major, minor;

	if (!t)
		BUG();

	if (sscanf(path, "%u:%u", &major, &minor) == 2) {
		/* Extract the major/minor numbers */
		dev = MKDEV(major, minor);
		if (MAJOR(dev) != major || MINOR(dev) != minor)
			return -EOVERFLOW;
	} else {
		/* convert the path to a device */
		if ((r = lookup_device(path, &dev)))
			return r;
	}

	dd = find_device(&t->devices, dev);
	if (!dd) {
		dd = kmalloc(sizeof(*dd), GFP_KERNEL);
		if (!dd)
			return -ENOMEM;

		dd->mode = mode;
		dd->bdev = NULL;

		if ((r = open_dev(dd, dev))) {
			kfree(dd);
			return r;
		}

		atomic_set(&dd->count, 0);
		list_add(&dd->list, &t->devices);

	} else if (dd->mode != (mode | dd->mode)) {
		r = upgrade_mode(dd, mode);
		if (r)
			return r;
	}
	atomic_inc(&dd->count);

	if (!check_device_area(dd, start, len)) {
		DMWARN("device %s too small for target", path);
		dm_put_device(ti, dd);
		return -EINVAL;
	}

	*result = dd;

	return 0;
}