#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/kmod.h>
-#include <linux/kobj_map.h>
#include <linux/mutex.h>
#include <linux/idr.h>
#include <linux/log2.h>
#include "blk.h"
-static DEFINE_MUTEX(block_class_lock);
static struct kobject *block_depr;
+struct bdev_map {
+ struct bdev_map *next;
+ dev_t dev;
+ unsigned long range;
+ struct module *owner;
+ struct kobject *(*probe)(dev_t, int *, void *);
+ int (*lock)(dev_t, void *);
+ void *data;
+} *bdev_map[255];
+static DEFINE_MUTEX(bdev_map_lock);
+
/* for extended dynamic devt allocation, currently only one major is used */
#define NR_EXT_DEVT (1 << MINORBITS)
int major;
char name[16];
} *major_names[BLKDEV_MAJOR_HASH_SIZE];
+static DEFINE_MUTEX(major_names_lock);
/* index in the above - for now: assume no multimajor ranges */
static inline int major_to_index(unsigned major)
{
struct blk_major_name *dp;
- mutex_lock(&block_class_lock);
+ mutex_lock(&major_names_lock);
for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next)
if (dp->major == offset)
seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
- mutex_unlock(&block_class_lock);
+ mutex_unlock(&major_names_lock);
}
#endif /* CONFIG_PROC_FS */
struct blk_major_name **n, *p;
int index, ret = 0;
- mutex_lock(&block_class_lock);
+ mutex_lock(&major_names_lock);
/* temporary */
if (major == 0) {
kfree(p);
}
out:
- mutex_unlock(&block_class_lock);
+ mutex_unlock(&major_names_lock);
return ret;
}
struct blk_major_name *p = NULL;
int index = major_to_index(major);
- mutex_lock(&block_class_lock);
+ mutex_lock(&major_names_lock);
for (n = &major_names[index]; *n; n = &(*n)->next)
if ((*n)->major == major)
break;
p = *n;
*n = p->next;
}
- mutex_unlock(&block_class_lock);
+ mutex_unlock(&major_names_lock);
kfree(p);
}
EXPORT_SYMBOL(unregister_blkdev);
-static struct kobj_map *bdev_map;
-
/**
* blk_mangle_minor - scatter minor numbers apart
* @minor: minor number to mangle
struct kobject *(*probe)(dev_t, int *, void *),
int (*lock)(dev_t, void *), void *data)
{
- kobj_map(bdev_map, devt, range, module, probe, lock, data);
-}
+ unsigned n = MAJOR(devt + range - 1) - MAJOR(devt) + 1;
+ unsigned index = MAJOR(devt);
+ unsigned i;
+ struct bdev_map *p;
+
+ n = min(n, 255u);
+ p = kmalloc_array(n, sizeof(struct bdev_map), GFP_KERNEL);
+ if (p == NULL)
+ return;
+ for (i = 0; i < n; i++, p++) {
+ p->owner = module;
+ p->probe = probe;
+ p->lock = lock;
+ p->dev = devt;
+ p->range = range;
+ p->data = data;
+ }
+
+ mutex_lock(&bdev_map_lock);
+ for (i = 0, p -= n; i < n; i++, p++, index++) {
+ struct bdev_map **s = &bdev_map[index % 255];
+ while (*s && (*s)->range < range)
+ s = &(*s)->next;
+ p->next = *s;
+ *s = p;
+ }
+ mutex_unlock(&bdev_map_lock);
+}
EXPORT_SYMBOL(blk_register_region);
void blk_unregister_region(dev_t devt, unsigned long range)
{
- kobj_unmap(bdev_map, devt, range);
+ unsigned n = MAJOR(devt + range - 1) - MAJOR(devt) + 1;
+ unsigned index = MAJOR(devt);
+ unsigned i;
+ struct bdev_map *found = NULL;
+
+ mutex_lock(&bdev_map_lock);
+ for (i = 0; i < min(n, 255u); i++, index++) {
+ struct bdev_map **s;
+ for (s = &bdev_map[index % 255]; *s; s = &(*s)->next) {
+ struct bdev_map *p = *s;
+ if (p->dev == devt && p->range == range) {
+ *s = p->next;
+ if (!found)
+ found = p;
+ break;
+ }
+ }
+ }
+ mutex_unlock(&bdev_map_lock);
+ kfree(found);
}
-
EXPORT_SYMBOL(blk_unregister_region);
static struct kobject *exact_match(dev_t devt, int *partno, void *data)
might_sleep();
+ if (WARN_ON_ONCE(!disk->queue))
+ return;
+
blk_integrity_del(disk);
disk_del_events(disk);
disk->flags &= ~GENHD_FL_UP;
up_write(&disk->lookup_sem);
- if (!(disk->flags & GENHD_FL_HIDDEN))
+ if (!(disk->flags & GENHD_FL_HIDDEN)) {
sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
- if (disk->queue) {
+
/*
* Unregister bdi before releasing device numbers (as they can
* get reused and we'd get clashes in sysfs).
*/
- if (!(disk->flags & GENHD_FL_HIDDEN))
- bdi_unregister(disk->queue->backing_dev_info);
- blk_unregister_queue(disk);
- } else {
- WARN_ON(1);
+ bdi_unregister(disk->queue->backing_dev_info);
}
+ blk_unregister_queue(disk);
+
if (!(disk->flags & GENHD_FL_HIDDEN))
blk_unregister_region(disk_devt(disk), disk->minors);
/*
return badblocks_store(disk->bb, page, len, 0);
}
+static struct gendisk *lookup_gendisk(dev_t dev, int *partno)
+{
+ struct kobject *kobj;
+ struct bdev_map *p;
+ unsigned long best = ~0UL;
+
+retry:
+ mutex_lock(&bdev_map_lock);
+ for (p = bdev_map[MAJOR(dev) % 255]; p; p = p->next) {
+ struct kobject *(*probe)(dev_t, int *, void *);
+ struct module *owner;
+ void *data;
+
+ if (p->dev > dev || p->dev + p->range - 1 < dev)
+ continue;
+ if (p->range - 1 >= best)
+ break;
+ if (!try_module_get(p->owner))
+ continue;
+ owner = p->owner;
+ data = p->data;
+ probe = p->probe;
+ best = p->range - 1;
+ *partno = dev - p->dev;
+ if (p->lock && p->lock(dev, data) < 0) {
+ module_put(owner);
+ continue;
+ }
+ mutex_unlock(&bdev_map_lock);
+ kobj = probe(dev, partno, data);
+ /* Currently ->owner protects _only_ ->probe() itself. */
+ module_put(owner);
+ if (kobj)
+ return dev_to_disk(kobj_to_dev(kobj));
+ goto retry;
+ }
+ mutex_unlock(&bdev_map_lock);
+ return NULL;
+}
+
+
/**
* get_gendisk - get partitioning information for a given device
* @devt: device to get partitioning information for
might_sleep();
if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
- struct kobject *kobj;
-
- kobj = kobj_lookup(bdev_map, devt, partno);
- if (kobj)
- disk = dev_to_disk(kobj_to_dev(kobj));
+ disk = lookup_gendisk(devt, partno);
} else {
struct hd_struct *part;
return NULL;
}
+static void bdev_map_init(void)
+{
+ struct bdev_map *base;
+ int i;
+
+ base = kzalloc(sizeof(*base), GFP_KERNEL);
+ if (!base)
+ panic("cannot allocate bdev_map");
+
+ base->dev = 1;
+ base->range = ~0 ;
+ base->probe = base_probe;
+ for (i = 0; i < 255; i++)
+ bdev_map[i] = base;
+}
+
static int __init genhd_device_init(void)
{
int error;
error = class_register(&block_class);
if (unlikely(error))
return error;
- bdev_map = kobj_map_init(base_probe, &block_class_lock);
+ bdev_map_init();
blk_dev_init();
register_blkdev(BLOCK_EXT_MAJOR, "blkext");
kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
}
-void set_device_ro(struct block_device *bdev, int flag)
-{
- bdev->bd_part->policy = flag;
-}
-
-EXPORT_SYMBOL(set_device_ro);
-
void set_disk_ro(struct gendisk *disk, int flag)
{
struct disk_part_iter piter;