Driver core: convert block from raw kobjects to core devices

This moves the block devices to /sys/class/block. It will create a
flat list of all block devices, with the disks and partitions in one
directory. For compatibility /sys/block is created and contains symlinks
to the disks.

  /sys/class/block
  |-- sda -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda
  |-- sda1 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1
  |-- sda10 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10
  |-- sda5 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5
  |-- sda6 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6
  |-- sda7 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7
  |-- sda8 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8
  |-- sda9 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9
  `-- sr0 -> ../../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0

  /sys/block/
  |-- sda -> ../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda
  `-- sr0 -> ../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 185 insertions, 235 deletions

diff --git a/block/genhd.c b/block/genhd.c
index 69aa7389d484..5e4ab4b37d9f 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -17,9 +17,10 @@
 #include <linux/buffer_head.h>
 #include <linux/mutex.h>
 
-struct kset *block_kset;
-static struct kset_uevent_ops block_uevent_ops;
-static DEFINE_MUTEX(block_subsys_lock);
+static DEFINE_MUTEX(block_class_lock);
+#ifndef CONFIG_SYSFS_DEPRECATED
+struct kobject *block_depr;
+#endif
 
 /*
  * Can be deleted altogether. Later.
@@ -38,19 +39,17 @@ static inline int major_to_index(int major)
 }
 
 #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);
+                mutex_lock(&block_class_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);
+                mutex_unlock(&block_class_lock);
         }
 }
-
 #endif /* CONFIG_PROC_FS */
 
 int register_blkdev(unsigned int major, const char *name)
@@ -58,7 +57,7 @@ int register_blkdev(unsigned int major, const char *name)
         struct blk_major_name **n, *p;
         int index, ret = 0;
 
-        mutex_lock(&block_subsys_lock);
+        mutex_lock(&block_class_lock);
 
         /* temporary */
         if (major == 0) {
@@ -103,7 +102,7 @@ int register_blkdev(unsigned int major, const char *name)
                 kfree(p);
         }
 out:
-        mutex_unlock(&block_subsys_lock);
+        mutex_unlock(&block_class_lock);
         return ret;
 }
 
@@ -115,7 +114,7 @@ void unregister_blkdev(unsigned int major, const char *name)
         struct blk_major_name *p = NULL;
         int index = major_to_index(major);
 
-        mutex_lock(&block_subsys_lock);
+        mutex_lock(&block_class_lock);
         for (n = &major_names[index]; *n; n = &(*n)->next)
                 if ((*n)->major == major)
                         break;
@@ -125,7 +124,7 @@ void unregister_blkdev(unsigned int major, const char *name)
                 p = *n;
                 *n = p->next;
         }
-        mutex_unlock(&block_subsys_lock);
+        mutex_unlock(&block_class_lock);
         kfree(p);
 }
 
@@ -138,29 +137,30 @@ static struct kobj_map *bdev_map;
  * 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,
+void blk_register_region(dev_t devt, 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);
+        kobj_map(bdev_map, devt, range, module, probe, lock, data);
 }
 
 EXPORT_SYMBOL(blk_register_region);
 
-void blk_unregister_region(dev_t dev, unsigned long range)
+void blk_unregister_region(dev_t devt, unsigned long range)
 {
-        kobj_unmap(bdev_map, dev, range);
+        kobj_unmap(bdev_map, devt, range);
 }
 
 EXPORT_SYMBOL(blk_unregister_region);
 
-static struct kobject *exact_match(dev_t dev, int *part, void *data)
+static struct kobject *exact_match(dev_t devt, int *part, void *data)
 {
         struct gendisk *p = data;
-        return &p->kobj;
+
+        return &p->dev.kobj;
 }
 
-static int exact_lock(dev_t dev, void *data)
+static int exact_lock(dev_t devt, void *data)
 {
         struct gendisk *p = data;
 
@@ -195,8 +195,6 @@ void unlink_gendisk(struct gendisk *disk)
                               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
@@ -204,10 +202,12 @@ void unlink_gendisk(struct gendisk *disk)
  * This function gets the structure containing partitioning
  * information for the given device @dev.
  */
-struct gendisk *get_gendisk(dev_t dev, int *part)
+struct gendisk *get_gendisk(dev_t devt, int *part)
 {
-        struct kobject *kobj = kobj_lookup(bdev_map, dev, part);
-        return  kobj ? to_disk(kobj) : NULL;
+        struct kobject *kobj = kobj_lookup(bdev_map, devt, part);
+        struct device *dev = kobj_to_dev(kobj);
+
+        return  kobj ? dev_to_disk(dev) : NULL;
 }
 
 /*
@@ -217,13 +217,17 @@ struct gendisk *get_gendisk(dev_t dev, int *part)
  */
 void __init printk_all_partitions(void)
 {
-        int n;
+        struct device *dev;
         struct gendisk *sgp;
+        char buf[BDEVNAME_SIZE];
+        int n;
 
-        mutex_lock(&block_subsys_lock);
+        mutex_lock(&block_class_lock);
         /* For each block device... */
-        list_for_each_entry(sgp, &block_kset->list, kobj.entry) {
-                char buf[BDEVNAME_SIZE];
+        list_for_each_entry(dev, &block_class.devices, node) {
+                if (dev->type != &disk_type)
+                        continue;
+                sgp = dev_to_disk(dev);
                 /*
                  * Don't show empty devices or things that have been surpressed
                  */
@@ -256,38 +260,46 @@ void __init printk_all_partitions(void)
                                 sgp->major, n + 1 + sgp->first_minor,
                                 (unsigned long long)sgp->part[n]->nr_sects >> 1,
                                 disk_name(sgp, n + 1, buf));
-                } /* partition subloop */
-        } /* Block device loop */
+                }
+        }
 
-        mutex_unlock(&block_subsys_lock);
-        return;
+        mutex_unlock(&block_class_lock);
 }
 
 #ifdef CONFIG_PROC_FS
 /* iterator */
 static void *part_start(struct seq_file *part, loff_t *pos)
 {
-        struct list_head *p;
-        loff_t l = *pos;
+        loff_t k = *pos;
+        struct device *dev;
 
-        mutex_lock(&block_subsys_lock);
-        list_for_each(p, &block_kset->list)
-                if (!l--)
-                        return list_entry(p, struct gendisk, kobj.entry);
+        mutex_lock(&block_class_lock);
+        list_for_each_entry(dev, &block_class.devices, node) {
+                if (dev->type != &disk_type)
+                        continue;
+                if (!k--)
+                        return dev_to_disk(dev);
+        }
         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;
+        struct gendisk *gp = v;
+        struct device *dev;
         ++*pos;
-        return p==&block_kset->list ? NULL :
-                list_entry(p, struct gendisk, kobj.entry);
+        list_for_each_entry(dev, &gp->dev.node, node) {
+                if (&dev->node == &block_class.devices)
+                        return NULL;
+                if (dev->type == &disk_type)
+                        return dev_to_disk(dev);
+        }
+        return NULL;
 }
 
 static void part_stop(struct seq_file *part, void *v)
 {
-        mutex_unlock(&block_subsys_lock);
+        mutex_unlock(&block_class_lock);
 }
 
 static int show_partition(struct seq_file *part, void *v)
@@ -296,7 +308,7 @@ static int show_partition(struct seq_file *part, void *v)
         int n;
         char buf[BDEVNAME_SIZE];
 
-        if (&sgp->kobj.entry == block_kset->list.next)
+        if (&sgp->dev.node == block_class.devices.next)
                 seq_puts(part, "major minor  #blocks  name\n\n");
 
         /* Don't show non-partitionable removeable devices or empty devices */
@@ -326,109 +338,81 @@ static int show_partition(struct seq_file *part, void *v)
 }
 
 struct seq_operations partitions_op = {
-        .start =part_start,
-        .next = part_next,
-        .stop = part_stop,
-        .show = show_partition
+        .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)
+static struct kobject *base_probe(dev_t devt, int *part, void *data)
 {
-        if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0)
+        if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
                 /* Make old-style 2.4 aliases work */
-                request_module("block-major-%d", MAJOR(dev));
+                request_module("block-major-%d", MAJOR(devt));
         return NULL;
 }
 
 static int __init genhd_device_init(void)
 {
-        bdev_map = kobj_map_init(base_probe, &block_subsys_lock);
+        class_register(&block_class);
+        bdev_map = kobj_map_init(base_probe, &block_class_lock);
         blk_dev_init();
-        block_kset = kset_create_and_add("block", &block_uevent_ops, NULL);
-        if (!block_kset) {
-                printk(KERN_WARNING "%s: kset_create error\n", __FUNCTION__);
-                return -ENOMEM;
-        }
+
+#ifndef CONFIG_SYSFS_DEPRECATED
+        /* create top-level block dir */
+        block_depr = kobject_create_and_add("block", NULL);
+#endif
         return 0;
 }
 
 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)
+static ssize_t disk_range_show(struct device *dev,
+                               struct device_attribute *attr, char *buf)
 {
-        struct gendisk *disk = to_disk(kobj);
-        struct disk_attribute *disk_attr =
-                container_of(attr,struct disk_attribute,attr);
-        ssize_t ret = -EIO;
+        struct gendisk *disk = dev_to_disk(dev);
 
-        if (disk_attr->show)
-                ret = disk_attr->show(disk,page);
-        return ret;
+        return sprintf(buf, "%d\n", disk->minors);
 }
 
-static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr,
-                               const char *page, size_t count)
+static ssize_t disk_removable_show(struct device *dev,
+                                   struct device_attribute *attr, char *buf)
 {
-        struct gendisk *disk = to_disk(kobj);
-        struct disk_attribute *disk_attr =
-                container_of(attr,struct disk_attribute,attr);
-        ssize_t ret = 0;
+        struct gendisk *disk = dev_to_disk(dev);
 
-        if (disk_attr->store)
-                ret = disk_attr->store(disk, page, count);
-        return ret;
+        return sprintf(buf, "%d\n",
+                       (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
 }
 
-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)
+static ssize_t disk_size_show(struct device *dev,
+                              struct device_attribute *attr, char *buf)
 {
-        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));
+        struct gendisk *disk = dev_to_disk(dev);
 
+        return sprintf(buf, "%llu\n", (unsigned long long)get_capacity(disk));
 }
-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_capability_read(struct gendisk *disk, char *page)
+
+static ssize_t disk_capability_show(struct device *dev,
+                                    struct device_attribute *attr, char *buf)
 {
-        return sprintf(page, "%x\n", disk->flags);
+        struct gendisk *disk = dev_to_disk(dev);
+
+        return sprintf(buf, "%x\n", disk->flags);
 }
-static ssize_t disk_stats_read(struct gendisk * disk, char *page)
+
+static ssize_t disk_stat_show(struct device *dev,
+                              struct device_attribute *attr, char *buf)
 {
+        struct gendisk *disk = dev_to_disk(dev);
+
         preempt_disable();
         disk_round_stats(disk);
         preempt_enable();
-        return sprintf(page,
+        return sprintf(buf,
                 "%8lu %8lu %8llu %8u "
                 "%8lu %8lu %8llu %8u "
                 "%8u %8u %8u"
@@ -445,40 +429,21 @@ static ssize_t disk_stats_read(struct gendisk * disk, char *page)
                 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_capability = {
-        .attr = {.name = "capability", .mode = S_IRUGO },
-        .show   = disk_capability_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_show(struct device *dev,
+                              struct device_attribute *attr, char *buf)
+{
+        struct gendisk *disk = dev_to_disk(dev);
+
+        return sprintf(buf, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
+}
 
-static ssize_t disk_fail_store(struct gendisk * disk,
+static ssize_t disk_fail_store(struct device *dev,
+                               struct device_attribute *attr,
                                const char *buf, size_t count)
 {
+        struct gendisk *disk = dev_to_disk(dev);
         int i;
 
         if (count > 0 && sscanf(buf, "%d", &i) > 0) {
@@ -490,134 +455,100 @@ static ssize_t disk_fail_store(struct gendisk * disk,
 
         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,
-        &disk_attr_capability.attr,
+static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
+static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
+static DEVICE_ATTR(size, S_IRUGO, disk_size_show, NULL);
+static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
+static DEVICE_ATTR(stat, S_IRUGO, disk_stat_show, NULL);
 #ifdef CONFIG_FAIL_MAKE_REQUEST
-        &disk_attr_fail.attr,
+static struct device_attribute dev_attr_fail =
+        __ATTR(make-it-fail, S_IRUGO|S_IWUSR, disk_fail_show, disk_fail_store);
 #endif
-        NULL,
+
+static struct attribute *disk_attrs[] = {
+        &dev_attr_range.attr,
+        &dev_attr_removable.attr,
+        &dev_attr_size.attr,
+        &dev_attr_capability.attr,
+        &dev_attr_stat.attr,
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+        &dev_attr_fail.attr,
+#endif
+        NULL
+};
+
+static struct attribute_group disk_attr_group = {
+        .attrs = disk_attrs,
+};
+
+static struct attribute_group *disk_attr_groups[] = {
+        &disk_attr_group,
+        NULL
 };
 
-static void disk_release(struct kobject * kobj)
+static void disk_release(struct device *dev)
 {
-        struct gendisk *disk = to_disk(kobj);
+        struct gendisk *disk = dev_to_disk(dev);
+
         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,
+struct class block_class = {
+        .name           = "block",
 };
 
-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,
-                        struct kobj_uevent_env *env)
-{
-        struct kobj_type *ktype = get_ktype(kobj);
-        struct device *physdev;
-        struct gendisk *disk;
-        struct hd_struct *part;
-
-        if (ktype == &ktype_block) {
-                disk = container_of(kobj, struct gendisk, kobj);
-                add_uevent_var(env, "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(env, "MINOR=%u",
-                               disk->first_minor + part->partno);
-        } else
-                return 0;
-
-        add_uevent_var(env, "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(env, "PHYSDEVPATH=%s", path);
-                kfree(path);
-
-                if (physdev->bus)
-                        add_uevent_var(env, "PHYSDEVBUS=%s", physdev->bus->name);
-
-                if (physdev->driver)
-                        add_uevent_var(env, physdev->driver->name);
-        }
-
-        return 0;
-}
-
-static struct kset_uevent_ops block_uevent_ops = {
-        .filter         = block_uevent_filter,
-        .uevent         = block_uevent,
+struct device_type disk_type = {
+        .name           = "disk",
+        .groups         = disk_attr_groups,
+        .release        = disk_release,
 };
 
 /*
  * 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;
+        struct device *dev;
 
-        mutex_lock(&block_subsys_lock);
-        list_for_each(p, &block_kset->list)
+        mutex_lock(&block_class_lock);
+        list_for_each_entry(dev, &block_class.devices, node) {
+                if (dev->type != &disk_type)
+                        continue;
                 if (!k--)
-                        return list_entry(p, struct gendisk, kobj.entry);
+                        return dev_to_disk(dev);
+        }
         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;
+        struct gendisk *gp = v;
+        struct device *dev;
+
         ++*pos;
-        return p==&block_kset->list ? NULL :
-                list_entry(p, struct gendisk, kobj.entry);
+        list_for_each_entry(dev, &gp->dev.node, node) {
+                if (&dev->node == &block_class.devices)
+                        return NULL;
+                if (dev->type == &disk_type)
+                        return dev_to_disk(dev);
+        }
+        return NULL;
 }
 
 static void diskstats_stop(struct seq_file *part, void *v)
 {
-        mutex_unlock(&block_subsys_lock);
+        mutex_unlock(&block_class_lock);
 }
 
 static int diskstats_show(struct seq_file *s, void *v)
@@ -627,7 +558,7 @@ static int diskstats_show(struct seq_file *s, void *v)
         int n = 0;
 
         /*
-        if (&sgp->kobj.entry == block_kset->list.next)
+        if (&gp->dev.kobj.entry == block_class.devices.next)
                 seq_puts(s,     "major minor name"
                                 "     rio rmerge rsect ruse wio wmerge "
                                 "wsect wuse running use aveq"
@@ -681,7 +612,7 @@ static void media_change_notify_thread(struct work_struct *work)
          * set enviroment vars to indicate which event this is for
          * so that user space will know to go check the media status.
          */
-        kobject_uevent_env(&gd->kobj, KOBJ_CHANGE, envp);
+        kobject_uevent_env(&gd->dev.kobj, KOBJ_CHANGE, envp);
         put_device(gd->driverfs_dev);
 }
 
@@ -692,6 +623,25 @@ void genhd_media_change_notify(struct gendisk *disk)
 }
 EXPORT_SYMBOL_GPL(genhd_media_change_notify);
 
+dev_t blk_lookup_devt(const char *name)
+{
+        struct device *dev;
+        dev_t devt = MKDEV(0, 0);
+
+        mutex_lock(&block_class_lock);
+        list_for_each_entry(dev, &block_class.devices, node) {
+                if (strcmp(dev->bus_id, name) == 0) {
+                        devt = dev->devt;
+                        break;
+                }
+        }
+        mutex_unlock(&block_class_lock);
+
+        return devt;
+}
+
+EXPORT_SYMBOL(blk_lookup_devt);
+
 struct gendisk *alloc_disk(int minors)
 {
         return alloc_disk_node(minors, -1);
@@ -719,10 +669,10 @@ struct gendisk *alloc_disk_node(int minors, int node_id)
                         }
                 }
                 disk->minors = minors;
-                disk->kobj.kset = block_kset;
-                disk->kobj.ktype = &ktype_block;
-                kobject_init(&disk->kobj);
                 rand_initialize_disk(disk);
+                disk->dev.class = &block_class;
+                disk->dev.type = &disk_type;
+                device_initialize(&disk->dev);
                 INIT_WORK(&disk->async_notify,
                         media_change_notify_thread);
         }
@@ -742,7 +692,7 @@ struct kobject *get_disk(struct gendisk *disk)
         owner = disk->fops->owner;
         if (owner && !try_module_get(owner))
                 return NULL;
-        kobj = kobject_get(&disk->kobj);
+        kobj = kobject_get(&disk->dev.kobj);
         if (kobj == NULL) {
                 module_put(owner);
                 return NULL;
@@ -756,7 +706,7 @@ EXPORT_SYMBOL(get_disk);
 void put_disk(struct gendisk *disk)
 {
         if (disk)
-                kobject_put(&disk->kobj);
+                kobject_put(&disk->dev.kobj);
 }
 
 EXPORT_SYMBOL(put_disk);
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 8b919940b2ab..3887b2a33ed0 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -4182,7 +4182,7 @@ int blk_register_queue(struct gendisk *disk)
         if (!q || !q->request_fn)
                 return -ENXIO;
 
-        q->kobj.parent = kobject_get(&disk->kobj);
+        q->kobj.parent = kobject_get(&disk->dev.kobj);
 
         ret = kobject_add(&q->kobj);
         if (ret < 0)
@@ -4209,6 +4209,6 @@ void blk_unregister_queue(struct gendisk *disk)
 
                 kobject_uevent(&q->kobj, KOBJ_REMOVE);
                 kobject_del(&q->kobj);
-                kobject_put(&disk->kobj);
+                kobject_put(&disk->dev.kobj);
         }
 }