1 files changed, 36 insertions, 15 deletions

diff --git a/block/genhd.c b/block/genhd.c
index c13cc77291af..e0ce23ac2ece 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -190,7 +190,6 @@ void add_disk(struct gendisk *disk)
                             disk->minors, NULL, exact_match, exact_lock, disk);
         register_disk(disk);
         blk_register_queue(disk);
-        blk_register_filter(disk);
 
         bdi = &disk->queue->backing_dev_info;
         bdi_register_dev(bdi, MKDEV(disk->major, disk->first_minor));
@@ -203,7 +202,6 @@ EXPORT_SYMBOL(del_gendisk);	/* in partitions/check.c */
 
 void unlink_gendisk(struct gendisk *disk)
 {
-        blk_unregister_filter(disk);
         sysfs_remove_link(&disk->dev.kobj, "bdi");
         bdi_unregister(&disk->queue->backing_dev_info);
         blk_unregister_queue(disk);
@@ -293,27 +291,30 @@ void __init printk_all_partitions(void)
 /* iterator */
 static int find_start(struct device *dev, void *data)
 {
-        loff_t k = *(loff_t *)data;
+        loff_t *k = data;
 
         if (dev->type != &disk_type)
                 return 0;
-        if (!k--)
+        if (!*k)
                 return 1;
+        (*k)--;
         return 0;
 }
 
 static void *part_start(struct seq_file *part, loff_t *pos)
 {
         struct device *dev;
-        loff_t n = *pos;
+        loff_t k = *pos;
 
-        if (!n)
-                seq_puts(part, "major minor  #blocks  name\n\n");
+        if (!k)
+                part->private = (void *)1LU;    /* tell show to print header */
 
         mutex_lock(&block_class_lock);
-        dev = class_find_device(&block_class, NULL, (void *)pos, find_start);
-        if (dev)
+        dev = class_find_device(&block_class, NULL, &k, find_start);
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -330,8 +331,10 @@ static void *part_next(struct seq_file *part, void *v, loff_t *pos)
         struct device *dev;
         ++*pos;
         dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
-        if (dev)
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -346,6 +349,17 @@ static int show_partition(struct seq_file *part, void *v)
         int n;
         char buf[BDEVNAME_SIZE];
 
+        /*
+         * Print header if start told us to do.  This is to preserve
+         * the original behavior of not printing header if no
+         * partition exists.  This hackery will be removed later with
+         * class iteration clean up.
+         */
+        if (part->private) {
+                seq_puts(part, "major minor  #blocks  name\n\n");
+                part->private = NULL;
+        }
+
         /* Don't show non-partitionable removeable devices or empty devices */
         if (!get_capacity(sgp) ||
                         (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
@@ -568,11 +582,14 @@ static struct device_type disk_type = {
 static void *diskstats_start(struct seq_file *part, loff_t *pos)
 {
         struct device *dev;
+        loff_t k = *pos;
 
         mutex_lock(&block_class_lock);
-        dev = class_find_device(&block_class, NULL, (void *)pos, find_start);
-        if (dev)
+        dev = class_find_device(&block_class, NULL, &k, find_start);
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -583,8 +600,10 @@ static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
 
         ++*pos;
         dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
-        if (dev)
+        if (dev) {
+                put_device(dev);
                 return dev_to_disk(dev);
+        }
         return NULL;
 }
 
@@ -712,10 +731,12 @@ dev_t blk_lookup_devt(const char *name, int part)
         mutex_lock(&block_class_lock);
         find.name = name;
         find.part = part;
-        dev = class_find_device(&block_class, NULL, (void *)&find, match_id);
-        if (dev)
+        dev = class_find_device(&block_class, NULL, &find, match_id);
+        if (dev) {
+                put_device(dev);
                 devt = MKDEV(MAJOR(dev->devt),
                              MINOR(dev->devt) + part);
+        }
         mutex_unlock(&block_class_lock);
 
         return devt;