[linux-2.6-block.git] / block / genhd.c

/*
 *  gendisk handling
 */

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/kobj_map.h>
#include <linux/buffer_head.h>
#include <linux/mutex.h>

struct subsystem block_subsys;
static DEFINE_MUTEX(block_subsys_lock);

/*
 * Can be deleted altogether. Later.
 *
 */
static struct blk_major_name {
	struct blk_major_name *next;
	int major;
	char name[16];
} *major_names[BLKDEV_MAJOR_HASH_SIZE];

/* index in the above - for now: assume no multimajor ranges */
static inline int major_to_index(int major)
{
	return major % BLKDEV_MAJOR_HASH_SIZE;
}

#ifdef CONFIG_PROC_FS

void blkdev_show(struct seq_file *f, off_t offset)
{
	struct blk_major_name *dp;

	if (offset < BLKDEV_MAJOR_HASH_SIZE) {
		mutex_lock(&block_subsys_lock);
		for (dp = major_names[offset]; dp; dp = dp->next)
			seq_printf(f, "%3d %s\n", dp->major, dp->name);
		mutex_unlock(&block_subsys_lock);
	}
}

#endif /* CONFIG_PROC_FS */

int register_blkdev(unsigned int major, const char *name)
{
	struct blk_major_name **n, *p;
	int index, ret = 0;

	mutex_lock(&block_subsys_lock);

	/* temporary */
	if (major == 0) {
		for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
			if (major_names[index] == NULL)
				break;
		}

		if (index == 0) {
			printk("register_blkdev: failed to get major for %s\n",
			       name);
			ret = -EBUSY;
			goto out;
		}
		major = index;
		ret = major;
	}

	p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
	if (p == NULL) {
		ret = -ENOMEM;
		goto out;
	}

	p->major = major;
	strlcpy(p->name, name, sizeof(p->name));
	p->next = NULL;
	index = major_to_index(major);

	for (n = &major_names[index]; *n; n = &(*n)->next) {
		if ((*n)->major == major)
			break;
	}
	if (!*n)
		*n = p;
	else
		ret = -EBUSY;

	if (ret < 0) {
		printk("register_blkdev: cannot get major %d for %s\n",
		       major, name);
		kfree(p);
	}
out:
	mutex_unlock(&block_subsys_lock);
	return ret;
}

EXPORT_SYMBOL(register_blkdev);

/* todo: make void - error printk here */
int unregister_blkdev(unsigned int major, const char *name)
{
	struct blk_major_name **n;
	struct blk_major_name *p = NULL;
	int index = major_to_index(major);
	int ret = 0;

	mutex_lock(&block_subsys_lock);
	for (n = &major_names[index]; *n; n = &(*n)->next)
		if ((*n)->major == major)
			break;
	if (!*n || strcmp((*n)->name, name))
		ret = -EINVAL;
	else {
		p = *n;
		*n = p->next;
	}
	mutex_unlock(&block_subsys_lock);
	kfree(p);

	return ret;
}

EXPORT_SYMBOL(unregister_blkdev);

static struct kobj_map *bdev_map;

/*
 * Register device numbers dev..(dev+range-1)
 * range must be nonzero
 * The hash chain is sorted on range, so that subranges can override.
 */
void blk_register_region(dev_t dev, unsigned long range, struct module *module,
			 struct kobject *(*probe)(dev_t, int *, void *),
			 int (*lock)(dev_t, void *), void *data)
{
	kobj_map(bdev_map, dev, range, module, probe, lock, data);
}

EXPORT_SYMBOL(blk_register_region);

void blk_unregister_region(dev_t dev, unsigned long range)
{
	kobj_unmap(bdev_map, dev, range);
}

EXPORT_SYMBOL(blk_unregister_region);

static struct kobject *exact_match(dev_t dev, int *part, void *data)
{
	struct gendisk *p = data;
	return &p->kobj;
}

static int exact_lock(dev_t dev, void *data)
{
	struct gendisk *p = data;

	if (!get_disk(p))
		return -1;
	return 0;
}

/**
 * add_disk - add partitioning information to kernel list
 * @disk: per-device partitioning information
 *
 * This function registers the partitioning information in @disk
 * with the kernel.
 */
void add_disk(struct gendisk *disk)
{
	disk->flags |= GENHD_FL_UP;
	blk_register_region(MKDEV(disk->major, disk->first_minor),
			    disk->minors, NULL, exact_match, exact_lock, disk);
	register_disk(disk);
	blk_register_queue(disk);
}

EXPORT_SYMBOL(add_disk);
EXPORT_SYMBOL(del_gendisk);	/* in partitions/check.c */

void unlink_gendisk(struct gendisk *disk)
{
	blk_unregister_queue(disk);
	blk_unregister_region(MKDEV(disk->major, disk->first_minor),
			      disk->minors);
}

#define to_disk(obj) container_of(obj,struct gendisk,kobj)

/**
 * get_gendisk - get partitioning information for a given device
 * @dev: device to get partitioning information for
 *
 * This function gets the structure containing partitioning
 * information for the given device @dev.
 */
struct gendisk *get_gendisk(dev_t dev, int *part)
{
	struct kobject *kobj = kobj_lookup(bdev_map, dev, part);
	return  kobj ? to_disk(kobj) : NULL;
}

#ifdef CONFIG_PROC_FS
/* iterator */
static void *part_start(struct seq_file *part, loff_t *pos)
{
	struct list_head *p;
	loff_t l = *pos;

	mutex_lock(&block_subsys_lock);
	list_for_each(p, &block_subsys.kset.list)
		if (!l--)
			return list_entry(p, struct gendisk, kobj.entry);
	return NULL;
}

static void *part_next(struct seq_file *part, void *v, loff_t *pos)
{
	struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
	++*pos;
	return p==&block_subsys.kset.list ? NULL : 
		list_entry(p, struct gendisk, kobj.entry);
}

static void part_stop(struct seq_file *part, void *v)
{
	mutex_unlock(&block_subsys_lock);
}

static int show_partition(struct seq_file *part, void *v)
{
	struct gendisk *sgp = v;
	int n;
	char buf[BDEVNAME_SIZE];

	if (&sgp->kobj.entry == block_subsys.kset.list.next)
		seq_puts(part, "major minor  #blocks  name\n\n");

	/* Don't show non-partitionable removeable devices or empty devices */
	if (!get_capacity(sgp) ||
			(sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
		return 0;
	if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
		return 0;

	/* show the full disk and all non-0 size partitions of it */
	seq_printf(part, "%4d  %4d %10llu %s\n",
		sgp->major, sgp->first_minor,
		(unsigned long long)get_capacity(sgp) >> 1,
		disk_name(sgp, 0, buf));
	for (n = 0; n < sgp->minors - 1; n++) {
		if (!sgp->part[n])
			continue;
		if (sgp->part[n]->nr_sects == 0)
			continue;
		seq_printf(part, "%4d  %4d %10llu %s\n",
			sgp->major, n + 1 + sgp->first_minor,
			(unsigned long long)sgp->part[n]->nr_sects >> 1 ,
			disk_name(sgp, n + 1, buf));
	}

	return 0;
}

struct seq_operations partitions_op = {
	.start =part_start,
	.next =	part_next,
	.stop =	part_stop,
	.show =	show_partition
};
#endif


extern int blk_dev_init(void);

static struct kobject *base_probe(dev_t dev, int *part, void *data)
{
	if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0)
		/* Make old-style 2.4 aliases work */
		request_module("block-major-%d", MAJOR(dev));
	return NULL;
}

static int __init genhd_device_init(void)
{
	int err;

	bdev_map = kobj_map_init(base_probe, &block_subsys_lock);
	blk_dev_init();
	err = subsystem_register(&block_subsys);
	if (err < 0)
		printk(KERN_WARNING "%s: subsystem_register error: %d\n",
			__FUNCTION__, err);
	return err;
}

subsys_initcall(genhd_device_init);


/*
 * kobject & sysfs bindings for block devices
 */
static ssize_t disk_attr_show(struct kobject *kobj, struct attribute *attr,
			      char *page)
{
	struct gendisk *disk = to_disk(kobj);
	struct disk_attribute *disk_attr =
		container_of(attr,struct disk_attribute,attr);
	ssize_t ret = -EIO;

	if (disk_attr->show)
		ret = disk_attr->show(disk,page);
	return ret;
}

static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr,
			       const char *page, size_t count)
{
	struct gendisk *disk = to_disk(kobj);
	struct disk_attribute *disk_attr =
		container_of(attr,struct disk_attribute,attr);
	ssize_t ret = 0;

	if (disk_attr->store)
		ret = disk_attr->store(disk, page, count);
	return ret;
}

static struct sysfs_ops disk_sysfs_ops = {
	.show	= &disk_attr_show,
	.store	= &disk_attr_store,
};

static ssize_t disk_uevent_store(struct gendisk * disk,
				 const char *buf, size_t count)
{
	kobject_uevent(&disk->kobj, KOBJ_ADD);
	return count;
}
static ssize_t disk_dev_read(struct gendisk * disk, char *page)
{
	dev_t base = MKDEV(disk->major, disk->first_minor); 
	return print_dev_t(page, base);
}
static ssize_t disk_range_read(struct gendisk * disk, char *page)
{
	return sprintf(page, "%d\n", disk->minors);
}
static ssize_t disk_removable_read(struct gendisk * disk, char *page)
{
	return sprintf(page, "%d\n",
		       (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));

}
static ssize_t disk_size_read(struct gendisk * disk, char *page)
{
	return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk));
}

static ssize_t disk_stats_read(struct gendisk * disk, char *page)
{
	preempt_disable();
	disk_round_stats(disk);
	preempt_enable();
	return sprintf(page,
		"%8lu %8lu %8llu %8u "
		"%8lu %8lu %8llu %8u "
		"%8u %8u %8u"
		"\n",
		disk_stat_read(disk, ios[READ]),
		disk_stat_read(disk, merges[READ]),
		(unsigned long long)disk_stat_read(disk, sectors[READ]),
		jiffies_to_msecs(disk_stat_read(disk, ticks[READ])),
		disk_stat_read(disk, ios[WRITE]),
		disk_stat_read(disk, merges[WRITE]),
		(unsigned long long)disk_stat_read(disk, sectors[WRITE]),
		jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])),
		disk->in_flight,
		jiffies_to_msecs(disk_stat_read(disk, io_ticks)),
		jiffies_to_msecs(disk_stat_read(disk, time_in_queue)));
}
static struct disk_attribute disk_attr_uevent = {
	.attr = {.name = "uevent", .mode = S_IWUSR },
	.store	= disk_uevent_store
};
static struct disk_attribute disk_attr_dev = {
	.attr = {.name = "dev", .mode = S_IRUGO },
	.show	= disk_dev_read
};
static struct disk_attribute disk_attr_range = {
	.attr = {.name = "range", .mode = S_IRUGO },
	.show	= disk_range_read
};
static struct disk_attribute disk_attr_removable = {
	.attr = {.name = "removable", .mode = S_IRUGO },
	.show	= disk_removable_read
};
static struct disk_attribute disk_attr_size = {
	.attr = {.name = "size", .mode = S_IRUGO },
	.show	= disk_size_read
};
static struct disk_attribute disk_attr_stat = {
	.attr = {.name = "stat", .mode = S_IRUGO },
	.show	= disk_stats_read
};

#ifdef CONFIG_FAIL_MAKE_REQUEST

static ssize_t disk_fail_store(struct gendisk * disk,
			       const char *buf, size_t count)
{
	int i;

	if (count > 0 && sscanf(buf, "%d", &i) > 0) {
		if (i == 0)
			disk->flags &= ~GENHD_FL_FAIL;
		else
			disk->flags |= GENHD_FL_FAIL;
	}

	return count;
}
static ssize_t disk_fail_read(struct gendisk * disk, char *page)
{
	return sprintf(page, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
}
static struct disk_attribute disk_attr_fail = {
	.attr = {.name = "make-it-fail", .mode = S_IRUGO | S_IWUSR },
	.store	= disk_fail_store,
	.show	= disk_fail_read
};

#endif

static struct attribute * default_attrs[] = {
	&disk_attr_uevent.attr,
	&disk_attr_dev.attr,
	&disk_attr_range.attr,
	&disk_attr_removable.attr,
	&disk_attr_size.attr,
	&disk_attr_stat.attr,
#ifdef CONFIG_FAIL_MAKE_REQUEST
	&disk_attr_fail.attr,
#endif
	NULL,
};

static void disk_release(struct kobject * kobj)
{
	struct gendisk *disk = to_disk(kobj);
	kfree(disk->random);
	kfree(disk->part);
	free_disk_stats(disk);
	kfree(disk);
}

static struct kobj_type ktype_block = {
	.release	= disk_release,
	.sysfs_ops	= &disk_sysfs_ops,
	.default_attrs	= default_attrs,
};

extern struct kobj_type ktype_part;

static int block_uevent_filter(struct kset *kset, struct kobject *kobj)
{
	struct kobj_type *ktype = get_ktype(kobj);

	return ((ktype == &ktype_block) || (ktype == &ktype_part));
}

static int block_uevent(struct kset *kset, struct kobject *kobj, char **envp,
			 int num_envp, char *buffer, int buffer_size)
{
	struct kobj_type *ktype = get_ktype(kobj);
	struct device *physdev;
	struct gendisk *disk;
	struct hd_struct *part;
	int length = 0;
	int i = 0;

	if (ktype == &ktype_block) {
		disk = container_of(kobj, struct gendisk, kobj);
		add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
			       &length, "MINOR=%u", disk->first_minor);
	} else if (ktype == &ktype_part) {
		disk = container_of(kobj->parent, struct gendisk, kobj);
		part = container_of(kobj, struct hd_struct, kobj);
		add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
			       &length, "MINOR=%u",
			       disk->first_minor + part->partno);
	} else
		return 0;

	add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
		       "MAJOR=%u", disk->major);

	/* add physical device, backing this device  */
	physdev = disk->driverfs_dev;
	if (physdev) {
		char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL);

		add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
			       &length, "PHYSDEVPATH=%s", path);
		kfree(path);

		if (physdev->bus)
			add_uevent_var(envp, num_envp, &i,
				       buffer, buffer_size, &length,
				       "PHYSDEVBUS=%s",
				       physdev->bus->name);

		if (physdev->driver)
			add_uevent_var(envp, num_envp, &i,
				       buffer, buffer_size, &length,
				       "PHYSDEVDRIVER=%s",
				       physdev->driver->name);
	}

	/* terminate, set to next free slot, shrink available space */
	envp[i] = NULL;
	envp = &envp[i];
	num_envp -= i;
	buffer = &buffer[length];
	buffer_size -= length;

	return 0;
}

static struct kset_uevent_ops block_uevent_ops = {
	.filter		= block_uevent_filter,
	.uevent		= block_uevent,
};

decl_subsys(block, &ktype_block, &block_uevent_ops);

/*
 * aggregate disk stat collector.  Uses the same stats that the sysfs
 * entries do, above, but makes them available through one seq_file.
 * Watching a few disks may be efficient through sysfs, but watching
 * all of them will be more efficient through this interface.
 *
 * The output looks suspiciously like /proc/partitions with a bunch of
 * extra fields.
 */

/* iterator */
static void *diskstats_start(struct seq_file *part, loff_t *pos)
{
	loff_t k = *pos;
	struct list_head *p;

	mutex_lock(&block_subsys_lock);
	list_for_each(p, &block_subsys.kset.list)
		if (!k--)
			return list_entry(p, struct gendisk, kobj.entry);
	return NULL;
}

static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
{
	struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
	++*pos;
	return p==&block_subsys.kset.list ? NULL :
		list_entry(p, struct gendisk, kobj.entry);
}

static void diskstats_stop(struct seq_file *part, void *v)
{
	mutex_unlock(&block_subsys_lock);
}

static int diskstats_show(struct seq_file *s, void *v)
{
	struct gendisk *gp = v;
	char buf[BDEVNAME_SIZE];
	int n = 0;

	/*
	if (&sgp->kobj.entry == block_subsys.kset.list.next)
		seq_puts(s,	"major minor name"
				"     rio rmerge rsect ruse wio wmerge "
				"wsect wuse running use aveq"
				"\n\n");
	*/
 
	preempt_disable();
	disk_round_stats(gp);
	preempt_enable();
	seq_printf(s, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
		gp->major, n + gp->first_minor, disk_name(gp, n, buf),
		disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
		(unsigned long long)disk_stat_read(gp, sectors[0]),
		jiffies_to_msecs(disk_stat_read(gp, ticks[0])),
		disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]),
		(unsigned long long)disk_stat_read(gp, sectors[1]),
		jiffies_to_msecs(disk_stat_read(gp, ticks[1])),
		gp->in_flight,
		jiffies_to_msecs(disk_stat_read(gp, io_ticks)),
		jiffies_to_msecs(disk_stat_read(gp, time_in_queue)));

	/* now show all non-0 size partitions of it */
	for (n = 0; n < gp->minors - 1; n++) {
		struct hd_struct *hd = gp->part[n];

		if (hd && hd->nr_sects)
			seq_printf(s, "%4d %4d %s %u %u %u %u\n",
				gp->major, n + gp->first_minor + 1,
				disk_name(gp, n + 1, buf),
				hd->ios[0], hd->sectors[0],
				hd->ios[1], hd->sectors[1]);
	}
 
	return 0;
}

struct seq_operations diskstats_op = {
	.start	= diskstats_start,
	.next	= diskstats_next,
	.stop	= diskstats_stop,
	.show	= diskstats_show
};

struct gendisk *alloc_disk(int minors)
{
	return alloc_disk_node(minors, -1);
}

struct gendisk *alloc_disk_node(int minors, int node_id)
{
	struct gendisk *disk;

	disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
	if (disk) {
		memset(disk, 0, sizeof(struct gendisk));
		if (!init_disk_stats(disk)) {
			kfree(disk);
			return NULL;
		}
		if (minors > 1) {
			int size = (minors - 1) * sizeof(struct hd_struct *);
			disk->part = kmalloc_node(size, GFP_KERNEL, node_id);
			if (!disk->part) {
				kfree(disk);
				return NULL;
			}
			memset(disk->part, 0, size);
		}
		disk->minors = minors;
		kobj_set_kset_s(disk,block_subsys);
		kobject_init(&disk->kobj);
		rand_initialize_disk(disk);
	}
	return disk;
}

EXPORT_SYMBOL(alloc_disk);
EXPORT_SYMBOL(alloc_disk_node);

struct kobject *get_disk(struct gendisk *disk)
{
	struct module *owner;
	struct kobject *kobj;

	if (!disk->fops)
		return NULL;
	owner = disk->fops->owner;
	if (owner && !try_module_get(owner))
		return NULL;
	kobj = kobject_get(&disk->kobj);
	if (kobj == NULL) {
		module_put(owner);
		return NULL;
	}
	return kobj;

}

EXPORT_SYMBOL(get_disk);

void put_disk(struct gendisk *disk)
{
	if (disk)
		kobject_put(&disk->kobj);
}

EXPORT_SYMBOL(put_disk);

void set_device_ro(struct block_device *bdev, int flag)
{
	if (bdev->bd_contains != bdev)
		bdev->bd_part->policy = flag;
	else
		bdev->bd_disk->policy = flag;
}

EXPORT_SYMBOL(set_device_ro);

void set_disk_ro(struct gendisk *disk, int flag)
{
	int i;
	disk->policy = flag;
	for (i = 0; i < disk->minors - 1; i++)
		if (disk->part[i]) disk->part[i]->policy = flag;
}

EXPORT_SYMBOL(set_disk_ro);

int bdev_read_only(struct block_device *bdev)
{
	if (!bdev)
		return 0;
	else if (bdev->bd_contains != bdev)
		return bdev->bd_part->policy;
	else
		return bdev->bd_disk->policy;
}

EXPORT_SYMBOL(bdev_read_only);

int invalidate_partition(struct gendisk *disk, int index)
{
	int res = 0;
	struct block_device *bdev = bdget_disk(disk, index);
	if (bdev) {
		fsync_bdev(bdev);
		res = __invalidate_device(bdev);
		bdput(bdev);
	}
	return res;
}

EXPORT_SYMBOL(invalidate_partition);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* gendisk handling
	3	*/
	4
1da177e4 LT	5	#include <linux/module.h>
	6	#include <linux/fs.h>
	7	#include <linux/genhd.h>
	8	#include <linux/kernel.h>
	9	#include <linux/blkdev.h>
	10	#include <linux/init.h>
	11	#include <linux/spinlock.h>
	12	#include <linux/seq_file.h>
	13	#include <linux/slab.h>
	14	#include <linux/kmod.h>
	15	#include <linux/kobj_map.h>
2ef41634	16	#include <linux/buffer_head.h>
58383af6	17	#include <linux/mutex.h>
1da177e4	18
b9d9c82b	19	struct subsystem block_subsys;
58383af6	20	static DEFINE_MUTEX(block_subsys_lock);
1da177e4 LT	21
	22	/*
	23	* Can be deleted altogether. Later.
	24	*
	25	*/
	26	static struct blk_major_name {
	27	struct blk_major_name *next;
	28	int major;
	29	char name[16];
68eef3b4	30	} *major_names[BLKDEV_MAJOR_HASH_SIZE];
1da177e4 LT	31
	32	/* index in the above - for now: assume no multimajor ranges */
	33	static inline int major_to_index(int major)
	34	{
68eef3b4	35	return major % BLKDEV_MAJOR_HASH_SIZE;
7170be5f NH	36	}
7170be5f NH	37
68eef3b4	38	#ifdef CONFIG_PROC_FS
7170be5f	39
68eef3b4	40	void blkdev_show(struct seq_file *f, off_t offset)
7170be5f	41	{
68eef3b4	42	struct blk_major_name *dp;
7170be5f	43
68eef3b4 JK	44	if (offset < BLKDEV_MAJOR_HASH_SIZE) {
	45	mutex_lock(&block_subsys_lock);
	46	for (dp = major_names[offset]; dp; dp = dp->next)
	47	seq_printf(f, "%3d %s\n", dp->major, dp->name);
	48	mutex_unlock(&block_subsys_lock);
1da177e4	49	}
1da177e4	50	}
7170be5f	51
68eef3b4	52	#endif /* CONFIG_PROC_FS */
1da177e4 LT	53
	54	int register_blkdev(unsigned int major, const char *name)
	55	{
	56	struct blk_major_name *n, p;
	57	int index, ret = 0;
	58
58383af6	59	mutex_lock(&block_subsys_lock);
1da177e4 LT	60
	61	/* temporary */
	62	if (major == 0) {
	63	for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
	64	if (major_names[index] == NULL)
	65	break;
	66	}
	67
	68	if (index == 0) {
	69	printk("register_blkdev: failed to get major for %s\n",
	70	name);
	71	ret = -EBUSY;
	72	goto out;
	73	}
	74	major = index;
	75	ret = major;
	76	}
	77
	78	p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
	79	if (p == NULL) {
	80	ret = -ENOMEM;
	81	goto out;
	82	}
	83
	84	p->major = major;
	85	strlcpy(p->name, name, sizeof(p->name));
	86	p->next = NULL;
	87	index = major_to_index(major);
	88
	89	for (n = &major_names[index]; n; n = &(n)->next) {
	90	if ((*n)->major == major)
	91	break;
	92	}
	93	if (!*n)
	94	*n = p;
	95	else
	96	ret = -EBUSY;
	97
	98	if (ret < 0) {
	99	printk("register_blkdev: cannot get major %d for %s\n",
	100	major, name);
	101	kfree(p);
	102	}
	103	out:
58383af6	104	mutex_unlock(&block_subsys_lock);
1da177e4 LT	105	return ret;
	106	}
	107
	108	EXPORT_SYMBOL(register_blkdev);
	109
	110	/* todo: make void - error printk here */
	111	int unregister_blkdev(unsigned int major, const char *name)
	112	{
	113	struct blk_major_name **n;
	114	struct blk_major_name *p = NULL;
	115	int index = major_to_index(major);
	116	int ret = 0;
	117
58383af6	118	mutex_lock(&block_subsys_lock);
1da177e4 LT	119	for (n = &major_names[index]; n; n = &(n)->next)
	120	if ((*n)->major == major)
	121	break;
	122	if (!n \|\| strcmp((n)->name, name))
	123	ret = -EINVAL;
	124	else {
	125	p = *n;
	126	*n = p->next;
	127	}
58383af6	128	mutex_unlock(&block_subsys_lock);
1da177e4 LT	129	kfree(p);
	130
	131	return ret;
	132	}
	133
	134	EXPORT_SYMBOL(unregister_blkdev);
	135
	136	static struct kobj_map *bdev_map;
	137
	138	/*
	139	* Register device numbers dev..(dev+range-1)
	140	* range must be nonzero
	141	* The hash chain is sorted on range, so that subranges can override.
	142	*/
	143	void blk_register_region(dev_t dev, unsigned long range, struct module *module,
	144	struct kobject (probe)(dev_t, int , void ),
	145	int (lock)(dev_t, void ), void *data)
	146	{
	147	kobj_map(bdev_map, dev, range, module, probe, lock, data);
	148	}
	149
	150	EXPORT_SYMBOL(blk_register_region);
	151
	152	void blk_unregister_region(dev_t dev, unsigned long range)
	153	{
	154	kobj_unmap(bdev_map, dev, range);
	155	}
	156
	157	EXPORT_SYMBOL(blk_unregister_region);
	158
	159	static struct kobject exact_match(dev_t dev, int part, void *data)
	160	{
	161	struct gendisk *p = data;
	162	return &p->kobj;
	163	}
	164
	165	static int exact_lock(dev_t dev, void *data)
	166	{
	167	struct gendisk *p = data;
	168
	169	if (!get_disk(p))
	170	return -1;
	171	return 0;
	172	}
	173
	174	/**
	175	* add_disk - add partitioning information to kernel list
	176	* @disk: per-device partitioning information
	177	*
	178	* This function registers the partitioning information in @disk
	179	* with the kernel.
	180	*/
	181	void add_disk(struct gendisk *disk)
	182	{
	183	disk->flags \|= GENHD_FL_UP;
	184	blk_register_region(MKDEV(disk->major, disk->first_minor),
	185	disk->minors, NULL, exact_match, exact_lock, disk);
	186	register_disk(disk);
	187	blk_register_queue(disk);
	188	}
	189
	190	EXPORT_SYMBOL(add_disk);
	191	EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */
	192
193	void unlink_gendisk(struct gendisk *disk)
194	{
195	blk_unregister_queue(disk);
196	blk_unregister_region(MKDEV(disk->major, disk->first_minor),
197	disk->minors);
198	}
199
200	#define to_disk(obj) container_of(obj,struct gendisk,kobj)
201
202	/**
203	* get_gendisk - get partitioning information for a given device
204	* @dev: device to get partitioning information for
205	*
206	* This function gets the structure containing partitioning
207	* information for the given device @dev.
208	*/
209	struct gendisk get_gendisk(dev_t dev, int part)
210	{
211	struct kobject *kobj = kobj_lookup(bdev_map, dev, part);
212	return kobj ? to_disk(kobj) : NULL;
213	}
214
215	#ifdef CONFIG_PROC_FS
216	/* iterator */
217	static void part_start(struct seq_file part, loff_t *pos)
218	{
219	struct list_head *p;
220	loff_t l = *pos;
221
58383af6	222	mutex_lock(&block_subsys_lock);
1da177e4 LT	223	list_for_each(p, &block_subsys.kset.list)
	224	if (!l--)
	225	return list_entry(p, struct gendisk, kobj.entry);
	226	return NULL;
	227	}
	228
	229	static void part_next(struct seq_file part, void v, loff_t pos)
	230	{
	231	struct list_head p = ((struct gendisk )v)->kobj.entry.next;
	232	++*pos;
	233	return p==&block_subsys.kset.list ? NULL :
	234	list_entry(p, struct gendisk, kobj.entry);
	235	}
	236
	237	static void part_stop(struct seq_file part, void v)
	238	{
58383af6	239	mutex_unlock(&block_subsys_lock);
1da177e4 LT	240	}
	241
	242	static int show_partition(struct seq_file part, void v)
	243	{
	244	struct gendisk *sgp = v;
	245	int n;
	246	char buf[BDEVNAME_SIZE];
	247
	248	if (&sgp->kobj.entry == block_subsys.kset.list.next)
	249	seq_puts(part, "major minor #blocks name\n\n");
	250
	251	/* Don't show non-partitionable removeable devices or empty devices */
	252	if (!get_capacity(sgp) \|\|
	253	(sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
	254	return 0;
	255	if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
	256	return 0;
	257
	258	/* show the full disk and all non-0 size partitions of it */
	259	seq_printf(part, "%4d %4d %10llu %s\n",
	260	sgp->major, sgp->first_minor,
	261	(unsigned long long)get_capacity(sgp) >> 1,
	262	disk_name(sgp, 0, buf));
	263	for (n = 0; n < sgp->minors - 1; n++) {
	264	if (!sgp->part[n])
	265	continue;
	266	if (sgp->part[n]->nr_sects == 0)
	267	continue;
	268	seq_printf(part, "%4d %4d %10llu %s\n",
	269	sgp->major, n + 1 + sgp->first_minor,
	270	(unsigned long long)sgp->part[n]->nr_sects >> 1 ,
	271	disk_name(sgp, n + 1, buf));
	272	}
	273
	274	return 0;
	275	}
	276
	277	struct seq_operations partitions_op = {
	278	.start =part_start,
	279	.next = part_next,
	280	.stop = part_stop,
	281	.show = show_partition
	282	};
	283	#endif
	284
	285
	286	extern int blk_dev_init(void);
	287
	288	static struct kobject base_probe(dev_t dev, int part, void *data)
	289	{
	290	if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0)
	291	/* Make old-style 2.4 aliases work */
	292	request_module("block-major-%d", MAJOR(dev));
	293	return NULL;
	294	}
	295
	296	static int __init genhd_device_init(void)
	297	{
87a57261 RD	298	int err;
87a57261 RD	299
58383af6	300	bdev_map = kobj_map_init(base_probe, &block_subsys_lock);
1da177e4	301	blk_dev_init();
87a57261 RD	302	err = subsystem_register(&block_subsys);
	303	if (err < 0)
	304	printk(KERN_WARNING "%s: subsystem_register error: %d\n",
	305	__FUNCTION__, err);
	306	return err;
1da177e4 LT	307	}
	308
	309	subsys_initcall(genhd_device_init);
	310
	311
	312
	313	/*
	314	* kobject & sysfs bindings for block devices
	315	*/
	316	static ssize_t disk_attr_show(struct kobject kobj, struct attribute attr,
	317	char *page)
	318	{
	319	struct gendisk *disk = to_disk(kobj);
	320	struct disk_attribute *disk_attr =
	321	container_of(attr,struct disk_attribute,attr);
6c1852a0	322	ssize_t ret = -EIO;
1da177e4 LT	323
	324	if (disk_attr->show)
	325	ret = disk_attr->show(disk,page);
	326	return ret;
	327	}
	328
a7fd6706 KS	329	static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr,
	330	const char *page, size_t count)
	331	{
	332	struct gendisk *disk = to_disk(kobj);
	333	struct disk_attribute *disk_attr =
	334	container_of(attr,struct disk_attribute,attr);
	335	ssize_t ret = 0;
	336
	337	if (disk_attr->store)
	338	ret = disk_attr->store(disk, page, count);
	339	return ret;
	340	}
	341
1da177e4 LT	342	static struct sysfs_ops disk_sysfs_ops = {
1da177e4 LT	343	.show = &disk_attr_show,
a7fd6706	344	.store = &disk_attr_store,
1da177e4 LT	345	};
1da177e4 LT	346
a7fd6706 KS	347	static ssize_t disk_uevent_store(struct gendisk * disk,
	348	const char *buf, size_t count)
	349	{
312c004d	350	kobject_uevent(&disk->kobj, KOBJ_ADD);
a7fd6706 KS	351	return count;
a7fd6706 KS	352	}
1da177e4 LT	353	static ssize_t disk_dev_read(struct gendisk * disk, char *page)
	354	{
	355	dev_t base = MKDEV(disk->major, disk->first_minor);
	356	return print_dev_t(page, base);
	357	}
	358	static ssize_t disk_range_read(struct gendisk * disk, char *page)
	359	{
	360	return sprintf(page, "%d\n", disk->minors);
	361	}
	362	static ssize_t disk_removable_read(struct gendisk * disk, char *page)
	363	{
	364	return sprintf(page, "%d\n",
	365	(disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
	366
	367	}
	368	static ssize_t disk_size_read(struct gendisk * disk, char *page)
	369	{
	370	return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk));
	371	}
	372
	373	static ssize_t disk_stats_read(struct gendisk * disk, char *page)
	374	{
	375	preempt_disable();
	376	disk_round_stats(disk);
	377	preempt_enable();
	378	return sprintf(page,
837c7878 BW	379	"%8lu %8lu %8llu %8u "
837c7878 BW	380	"%8lu %8lu %8llu %8u "
1da177e4 LT	381	"%8u %8u %8u"
1da177e4 LT	382	"\n",
47a00410 JA	383	disk_stat_read(disk, ios[READ]),
	384	disk_stat_read(disk, merges[READ]),
	385	(unsigned long long)disk_stat_read(disk, sectors[READ]),
	386	jiffies_to_msecs(disk_stat_read(disk, ticks[READ])),
	387	disk_stat_read(disk, ios[WRITE]),
	388	disk_stat_read(disk, merges[WRITE]),
	389	(unsigned long long)disk_stat_read(disk, sectors[WRITE]),
	390	jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])),
1da177e4 LT	391	disk->in_flight,
	392	jiffies_to_msecs(disk_stat_read(disk, io_ticks)),
	393	jiffies_to_msecs(disk_stat_read(disk, time_in_queue)));
	394	}
a7fd6706 KS	395	static struct disk_attribute disk_attr_uevent = {
	396	.attr = {.name = "uevent", .mode = S_IWUSR },
	397	.store = disk_uevent_store
	398	};
1da177e4 LT	399	static struct disk_attribute disk_attr_dev = {
	400	.attr = {.name = "dev", .mode = S_IRUGO },
	401	.show = disk_dev_read
	402	};
	403	static struct disk_attribute disk_attr_range = {
	404	.attr = {.name = "range", .mode = S_IRUGO },
	405	.show = disk_range_read
	406	};
	407	static struct disk_attribute disk_attr_removable = {
	408	.attr = {.name = "removable", .mode = S_IRUGO },
	409	.show = disk_removable_read
	410	};
	411	static struct disk_attribute disk_attr_size = {
	412	.attr = {.name = "size", .mode = S_IRUGO },
	413	.show = disk_size_read
	414	};
	415	static struct disk_attribute disk_attr_stat = {
	416	.attr = {.name = "stat", .mode = S_IRUGO },
	417	.show = disk_stats_read
	418	};
	419
c17bb495 AM	420	#ifdef CONFIG_FAIL_MAKE_REQUEST
	421
	422	static ssize_t disk_fail_store(struct gendisk * disk,
	423	const char *buf, size_t count)
	424	{
	425	int i;
	426
	427	if (count > 0 && sscanf(buf, "%d", &i) > 0) {
	428	if (i == 0)
	429	disk->flags &= ~GENHD_FL_FAIL;
	430	else
	431	disk->flags \|= GENHD_FL_FAIL;
	432	}
	433
	434	return count;
	435	}
	436	static ssize_t disk_fail_read(struct gendisk * disk, char *page)
	437	{
	438	return sprintf(page, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
	439	}
	440	static struct disk_attribute disk_attr_fail = {
	441	.attr = {.name = "make-it-fail", .mode = S_IRUGO \| S_IWUSR },
	442	.store = disk_fail_store,
	443	.show = disk_fail_read
	444	};
	445
	446	#endif
	447
1da177e4	448	static struct attribute * default_attrs[] = {
a7fd6706	449	&disk_attr_uevent.attr,
1da177e4 LT	450	&disk_attr_dev.attr,
	451	&disk_attr_range.attr,
	452	&disk_attr_removable.attr,
	453	&disk_attr_size.attr,
	454	&disk_attr_stat.attr,
c17bb495 AM	455	#ifdef CONFIG_FAIL_MAKE_REQUEST
	456	&disk_attr_fail.attr,
	457	#endif
1da177e4 LT	458	NULL,
	459	};
	460
	461	static void disk_release(struct kobject * kobj)
	462	{
	463	struct gendisk *disk = to_disk(kobj);
	464	kfree(disk->random);
	465	kfree(disk->part);
	466	free_disk_stats(disk);
	467	kfree(disk);
	468	}
	469
	470	static struct kobj_type ktype_block = {
	471	.release = disk_release,
	472	.sysfs_ops = &disk_sysfs_ops,
	473	.default_attrs = default_attrs,
	474	};
	475
	476	extern struct kobj_type ktype_part;
	477
312c004d	478	static int block_uevent_filter(struct kset kset, struct kobject kobj)
1da177e4 LT	479	{
	480	struct kobj_type *ktype = get_ktype(kobj);
	481
	482	return ((ktype == &ktype_block) \|\| (ktype == &ktype_part));
	483	}
	484
312c004d	485	static int block_uevent(struct kset kset, struct kobject kobj, char **envp,
1da177e4 LT	486	int num_envp, char *buffer, int buffer_size)
	487	{
	488	struct kobj_type *ktype = get_ktype(kobj);
	489	struct device *physdev;
	490	struct gendisk *disk;
	491	struct hd_struct *part;
	492	int length = 0;
	493	int i = 0;
	494
	495	if (ktype == &ktype_block) {
	496	disk = container_of(kobj, struct gendisk, kobj);
312c004d KS	497	add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
312c004d KS	498	&length, "MINOR=%u", disk->first_minor);
1da177e4 LT	499	} else if (ktype == &ktype_part) {
	500	disk = container_of(kobj->parent, struct gendisk, kobj);
	501	part = container_of(kobj, struct hd_struct, kobj);
312c004d KS	502	add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
	503	&length, "MINOR=%u",
	504	disk->first_minor + part->partno);
1da177e4 LT	505	} else
	506	return 0;
	507
312c004d KS	508	add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
312c004d KS	509	"MAJOR=%u", disk->major);
1da177e4 LT	510
	511	/* add physical device, backing this device */
	512	physdev = disk->driverfs_dev;
	513	if (physdev) {
	514	char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL);
	515
312c004d KS	516	add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
312c004d KS	517	&length, "PHYSDEVPATH=%s", path);
1da177e4 LT	518	kfree(path);
	519
	520	if (physdev->bus)
312c004d KS	521	add_uevent_var(envp, num_envp, &i,
	522	buffer, buffer_size, &length,
	523	"PHYSDEVBUS=%s",
	524	physdev->bus->name);
1da177e4 LT	525
1da177e4 LT	526	if (physdev->driver)
312c004d KS	527	add_uevent_var(envp, num_envp, &i,
	528	buffer, buffer_size, &length,
	529	"PHYSDEVDRIVER=%s",
	530	physdev->driver->name);
1da177e4 LT	531	}
	532
	533	/* terminate, set to next free slot, shrink available space */
	534	envp[i] = NULL;
	535	envp = &envp[i];
	536	num_envp -= i;
	537	buffer = &buffer[length];
	538	buffer_size -= length;
	539
	540	return 0;
	541	}
	542
312c004d KS	543	static struct kset_uevent_ops block_uevent_ops = {
	544	.filter = block_uevent_filter,
	545	.uevent = block_uevent,
1da177e4 LT	546	};
1da177e4 LT	547
b9d9c82b	548	decl_subsys(block, &ktype_block, &block_uevent_ops);
1da177e4 LT	549
	550	/*
	551	* aggregate disk stat collector. Uses the same stats that the sysfs
	552	* entries do, above, but makes them available through one seq_file.
	553	* Watching a few disks may be efficient through sysfs, but watching
	554	* all of them will be more efficient through this interface.
	555	*
	556	* The output looks suspiciously like /proc/partitions with a bunch of
	557	* extra fields.
	558	*/
	559
	560	/* iterator */
	561	static void diskstats_start(struct seq_file part, loff_t *pos)
	562	{
	563	loff_t k = *pos;
	564	struct list_head *p;
	565
58383af6	566	mutex_lock(&block_subsys_lock);
1da177e4 LT	567	list_for_each(p, &block_subsys.kset.list)
	568	if (!k--)
	569	return list_entry(p, struct gendisk, kobj.entry);
	570	return NULL;
	571	}
	572
	573	static void diskstats_next(struct seq_file part, void v, loff_t pos)
	574	{
	575	struct list_head p = ((struct gendisk )v)->kobj.entry.next;
	576	++*pos;
	577	return p==&block_subsys.kset.list ? NULL :
	578	list_entry(p, struct gendisk, kobj.entry);
	579	}
	580
	581	static void diskstats_stop(struct seq_file part, void v)
	582	{
58383af6	583	mutex_unlock(&block_subsys_lock);
1da177e4 LT	584	}
	585
	586	static int diskstats_show(struct seq_file s, void v)
	587	{
	588	struct gendisk *gp = v;
	589	char buf[BDEVNAME_SIZE];
	590	int n = 0;
	591
	592	/*
	593	if (&sgp->kobj.entry == block_subsys.kset.list.next)
	594	seq_puts(s, "major minor name"
	595	" rio rmerge rsect ruse wio wmerge "
	596	"wsect wuse running use aveq"
	597	"\n\n");
	598	*/
	599
	600	preempt_disable();
	601	disk_round_stats(gp);
	602	preempt_enable();
837c7878	603	seq_printf(s, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
1da177e4	604	gp->major, n + gp->first_minor, disk_name(gp, n, buf),
a362357b JA	605	disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
	606	(unsigned long long)disk_stat_read(gp, sectors[0]),
	607	jiffies_to_msecs(disk_stat_read(gp, ticks[0])),
	608	disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]),
	609	(unsigned long long)disk_stat_read(gp, sectors[1]),
	610	jiffies_to_msecs(disk_stat_read(gp, ticks[1])),
1da177e4 LT	611	gp->in_flight,
	612	jiffies_to_msecs(disk_stat_read(gp, io_ticks)),
	613	jiffies_to_msecs(disk_stat_read(gp, time_in_queue)));
	614
	615	/* now show all non-0 size partitions of it */
	616	for (n = 0; n < gp->minors - 1; n++) {
	617	struct hd_struct *hd = gp->part[n];
	618
	619	if (hd && hd->nr_sects)
	620	seq_printf(s, "%4d %4d %s %u %u %u %u\n",
	621	gp->major, n + gp->first_minor + 1,
	622	disk_name(gp, n + 1, buf),
a362357b JA	623	hd->ios[0], hd->sectors[0],
a362357b JA	624	hd->ios[1], hd->sectors[1]);
1da177e4 LT	625	}
	626
	627	return 0;
	628	}
	629
	630	struct seq_operations diskstats_op = {
	631	.start = diskstats_start,
	632	.next = diskstats_next,
	633	.stop = diskstats_stop,
	634	.show = diskstats_show
	635	};
	636
1da177e4 LT	637	struct gendisk *alloc_disk(int minors)
1da177e4 LT	638	{
1946089a CL	639	return alloc_disk_node(minors, -1);
	640	}
	641
	642	struct gendisk *alloc_disk_node(int minors, int node_id)
	643	{
	644	struct gendisk *disk;
	645
	646	disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
1da177e4 LT	647	if (disk) {
	648	memset(disk, 0, sizeof(struct gendisk));
	649	if (!init_disk_stats(disk)) {
	650	kfree(disk);
	651	return NULL;
	652	}
	653	if (minors > 1) {
	654	int size = (minors - 1) * sizeof(struct hd_struct *);
1946089a	655	disk->part = kmalloc_node(size, GFP_KERNEL, node_id);
1da177e4 LT	656	if (!disk->part) {
	657	kfree(disk);
	658	return NULL;
	659	}
	660	memset(disk->part, 0, size);
	661	}
	662	disk->minors = minors;
	663	kobj_set_kset_s(disk,block_subsys);
	664	kobject_init(&disk->kobj);
	665	rand_initialize_disk(disk);
	666	}
	667	return disk;
	668	}
	669
	670	EXPORT_SYMBOL(alloc_disk);
1946089a	671	EXPORT_SYMBOL(alloc_disk_node);
1da177e4 LT	672
	673	struct kobject get_disk(struct gendisk disk)
	674	{
	675	struct module *owner;
	676	struct kobject *kobj;
	677
	678	if (!disk->fops)
	679	return NULL;
	680	owner = disk->fops->owner;
	681	if (owner && !try_module_get(owner))
	682	return NULL;
	683	kobj = kobject_get(&disk->kobj);
	684	if (kobj == NULL) {
	685	module_put(owner);
	686	return NULL;
	687	}
	688	return kobj;
	689
	690	}
	691
	692	EXPORT_SYMBOL(get_disk);
	693
	694	void put_disk(struct gendisk *disk)
	695	{
	696	if (disk)
	697	kobject_put(&disk->kobj);
	698	}
	699
	700	EXPORT_SYMBOL(put_disk);
	701
	702	void set_device_ro(struct block_device *bdev, int flag)
	703	{
	704	if (bdev->bd_contains != bdev)
	705	bdev->bd_part->policy = flag;
	706	else
	707	bdev->bd_disk->policy = flag;
	708	}
	709
	710	EXPORT_SYMBOL(set_device_ro);
	711
	712	void set_disk_ro(struct gendisk *disk, int flag)
	713	{
	714	int i;
	715	disk->policy = flag;
	716	for (i = 0; i < disk->minors - 1; i++)
	717	if (disk->part[i]) disk->part[i]->policy = flag;
	718	}
	719
	720	EXPORT_SYMBOL(set_disk_ro);
	721
	722	int bdev_read_only(struct block_device *bdev)
	723	{
	724	if (!bdev)
	725	return 0;
	726	else if (bdev->bd_contains != bdev)
	727	return bdev->bd_part->policy;
	728	else
	729	return bdev->bd_disk->policy;
	730	}
	731
	732	EXPORT_SYMBOL(bdev_read_only);
	733
	734	int invalidate_partition(struct gendisk *disk, int index)
	735	{
736	int res = 0;
737	struct block_device *bdev = bdget_disk(disk, index);
738	if (bdev) {
2ef41634 CH	739	fsync_bdev(bdev);
2ef41634 CH	740	res = __invalidate_device(bdev);
1da177e4 LT	741	bdput(bdev);
	742	}
	743	return res;
	744	}
	745
	746	EXPORT_SYMBOL(invalidate_partition);