block devices: use list and lock in block_subsys, instead of those defined in genhd.c.

Since block_subsys already contains a list and a lock, use those, instead
of defining our own static ones.

This allows struct gendisk::full_list to be removed.

struct gendisk::list is also apparently unused, so it is removed also.

diff --git a/drivers/block/genhd.c b/drivers/block/genhd.c
index 1faa7afc5c857aad5a925584c8e49d5b9d7d10c7..f0eabbf2df1151215df403014d910271347c069f 100644 (file)
--- a/drivers/block/genhd.c
+++ b/drivers/block/genhd.c
@@ -27,12 +27,8 @@
 #include <linux/kmod.h>
 
 
-static rwlock_t gendisk_lock;
+static struct subsystem block_subsys;
 
-/*
- * Global kernel list of partitioning information.
- */
-static LIST_HEAD(gendisk_list);
 
 struct blk_probe {
        struct blk_probe *next;
@@ -63,19 +59,19 @@ void blk_register_region(dev_t dev, unsigned long range, struct module *module,
        p->dev = dev;
        p->range = range;
        p->data = data;
-       write_lock(&gendisk_lock);
+       down_write(&block_subsys.rwsem);
        for (s = &probes[index]; *s && (*s)->range < range; s = &(*s)->next)
                ;
        p->next = *s;
        *s = p;
-       write_unlock(&gendisk_lock);
+       up_write(&block_subsys.rwsem);
 }
 
 void blk_unregister_region(dev_t dev, unsigned long range)
 {
        int index = dev_to_index(dev);
        struct blk_probe **s;
-       write_lock(&gendisk_lock);
+       down_write(&block_subsys.rwsem);
        for (s = &probes[index]; *s; s = &(*s)->next) {
                struct blk_probe *p = *s;
                if (p->dev == dev || p->range == range) {
@@ -84,7 +80,7 @@ void blk_unregister_region(dev_t dev, unsigned long range)
                        break;
                }
        }
-       write_unlock(&gendisk_lock);
+       up_write(&block_subsys.rwsem);
 }
 
 EXPORT_SYMBOL(blk_register_region);
@@ -112,9 +108,6 @@ static int exact_lock(dev_t dev, void *data)
  */
 void add_disk(struct gendisk *disk)
 {
-       write_lock(&gendisk_lock);
-       list_add_tail(&disk->full_list, &gendisk_list);
-       write_unlock(&gendisk_lock);
        disk->flags |= GENHD_FL_UP;
        blk_register_region(MKDEV(disk->major, disk->first_minor), disk->minors,
                        NULL, exact_match, exact_lock, disk);
@@ -126,9 +119,6 @@ EXPORT_SYMBOL(del_gendisk);
 
 void unlink_gendisk(struct gendisk *disk)
 {
-       write_lock(&gendisk_lock);
-       list_del_init(&disk->full_list);
-       write_unlock(&gendisk_lock);
        blk_unregister_region(MKDEV(disk->major, disk->first_minor),
                              disk->minors);
 }
@@ -149,7 +139,7 @@ get_gendisk(dev_t dev, int *part)
        unsigned best = ~0U;
 
 retry:
-       read_lock(&gendisk_lock);
+       down_read(&block_subsys.rwsem);
        for (p = probes[index]; p; p = p->next) {
                struct gendisk *(*probe)(dev_t, int *, void *);
                struct module *owner;
@@ -157,7 +147,7 @@ retry:
                if (p->dev > dev || p->dev + p->range <= dev)
                        continue;
                if (p->range >= best) {
-                       read_unlock(&gendisk_lock);
+                       up_read(&block_subsys.rwsem);
                        return NULL;
                }
                if (!try_module_get(p->owner))
@@ -171,7 +161,7 @@ retry:
                        module_put(owner);
                        continue;
                }
-               read_unlock(&gendisk_lock);
+               up_read(&block_subsys.rwsem);
                disk = probe(dev, part, data);
                /* Currently ->owner protects _only_ ->probe() itself. */
                module_put(owner);
@@ -179,7 +169,7 @@ retry:
                        return disk;
                goto retry;
        }
-       read_unlock(&gendisk_lock);
+       up_read(&block_subsys.rwsem);
        return NULL;
 }
 
@@ -190,23 +180,24 @@ static void *part_start(struct seq_file *part, loff_t *pos)
        struct list_head *p;
        loff_t l = *pos;
 
-       read_lock(&gendisk_lock);
-       list_for_each(p, &gendisk_list)
+       down_read(&block_subsys.rwsem);
+       list_for_each(p, &block_subsys.kset.list)
                if (!l--)
-                       return list_entry(p, struct gendisk, full_list);
+                       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)->full_list.next;
+       struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
        ++*pos;
-       return p==&gendisk_list ? NULL : list_entry(p, struct gendisk, full_list);
+       return p==&block_subsys.kset.list ? NULL : 
+               list_entry(p, struct gendisk, kobj.entry);
 }
 
 static void part_stop(struct seq_file *part, void *v)
 {
-       read_unlock(&gendisk_lock);
+       up_read(&block_subsys.rwsem);
 }
 
 static int show_partition(struct seq_file *part, void *v)
@@ -215,7 +206,7 @@ static int show_partition(struct seq_file *part, void *v)
        int n;
        char buf[64];
 
-       if (&sgp->full_list == gendisk_list.next)
+       if (&sgp->kobj.entry == block_subsys.kset.list.next)
                seq_puts(part, "major minor  #blocks  name\n\n");
 
        /* Don't show non-partitionable devices or empty devices */
@@ -258,13 +249,10 @@ static struct gendisk *base_probe(dev_t dev, int *part, void *data)
        return NULL;
 }
 
-struct subsystem block_subsys;
-
 int __init device_init(void)
 {
        struct blk_probe *base = kmalloc(sizeof(struct blk_probe), GFP_KERNEL);
        int i;
-       rwlock_init(&gendisk_lock);
        memset(base, 0, sizeof(struct blk_probe));
        base->dev = MKDEV(1,0);
        base->range = MKDEV(MAX_BLKDEV-1, 255) - base->dev + 1;
@@ -390,7 +378,10 @@ static struct kobj_type ktype_block = {
        .default_attrs  = default_attrs,
 };
 
-decl_subsys(block,&ktype_block);
+
+/* declare block_subsys. */
+static decl_subsys(block,&ktype_block);
+
 
 struct gendisk *alloc_disk(int minors)
 {
@@ -411,7 +402,6 @@ struct gendisk *alloc_disk(int minors)
                        disk->minor_shift++;
                kobj_set_kset_s(disk,block_subsys);
                kobject_init(&disk->kobj);
-               INIT_LIST_HEAD(&disk->full_list);
                rand_initialize_disk(disk);
        }
        return disk;

diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 548e477daa4b54672b80248d0fa7fef7d84f9e3c..6cdf3f364b2ea0bd350624f115d0e76941c254df 100644 (file)
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -85,8 +85,6 @@ struct gendisk {
        struct request_queue *queue;
        void *private_data;
        sector_t capacity;
-       struct list_head list;
-       struct list_head full_list;
 
        int flags;
        int number;                     /* devfs crap */