[PATCH] kobj_map semaphore to mutex conversion

Convert the kobj_map code to use a mutex instead of a semaphore.  It
converts the single two users as well, genhd.c and char_dev.c.

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 16 insertions, 15 deletions

diff --git a/block/genhd.c b/block/genhd.c
index db57546a709d..64510fd88621 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -15,12 +15,13 @@
 #include <linux/kmod.h>
 #include <linux/kobj_map.h>
 #include <linux/buffer_head.h>
+#include <linux/mutex.h>
 
 #define MAX_PROBE_HASH 255      /* random */
 
 static struct subsystem block_subsys;
 
-static DECLARE_MUTEX(block_subsys_sem);
+static DEFINE_MUTEX(block_subsys_lock);
 
 /*
  * Can be deleted altogether. Later.
@@ -46,7 +47,7 @@ struct blkdev_info {
 /*
  * iterate over a list of blkdev_info structures.  allows
  * the major_names array to be iterated over from outside this file
- * must be called with the block_subsys_sem held
+ * must be called with the block_subsys_lock held
  */
 void *get_next_blkdev(void *dev)
 {
@@ -85,20 +86,20 @@ out:
 
 void *acquire_blkdev_list(void)
 {
-        down(&block_subsys_sem);
+        mutex_lock(&block_subsys_lock);
         return get_next_blkdev(NULL);
 }
 
 void release_blkdev_list(void *dev)
 {
-        up(&block_subsys_sem);
+        mutex_unlock(&block_subsys_lock);
         kfree(dev);
 }
 
 
 /*
  * Count the number of records in the blkdev_list.
- * must be called with the block_subsys_sem held
+ * must be called with the block_subsys_lock held
  */
 int count_blkdev_list(void)
 {
@@ -118,7 +119,7 @@ int count_blkdev_list(void)
 /*
  * extract the major and name values from a blkdev_info struct
  * passed in as a void to *dev.  Must be called with
- * block_subsys_sem held
+ * block_subsys_lock held
  */
 int get_blkdev_info(void *dev, int *major, char **name)
 {
@@ -138,7 +139,7 @@ int register_blkdev(unsigned int major, const char *name)
         struct blk_major_name **n, *p;
         int index, ret = 0;
 
-        down(&block_subsys_sem);
+        mutex_lock(&block_subsys_lock);
 
         /* temporary */
         if (major == 0) {
@@ -183,7 +184,7 @@ int register_blkdev(unsigned int major, const char *name)
                 kfree(p);
         }
 out:
-        up(&block_subsys_sem);
+        mutex_unlock(&block_subsys_lock);
         return ret;
 }
 
@@ -197,7 +198,7 @@ int unregister_blkdev(unsigned int major, const char *name)
         int index = major_to_index(major);
         int ret = 0;
 
-        down(&block_subsys_sem);
+        mutex_lock(&block_subsys_lock);
         for (n = &major_names[index]; *n; n = &(*n)->next)
                 if ((*n)->major == major)
                         break;
@@ -207,7 +208,7 @@ int unregister_blkdev(unsigned int major, const char *name)
                 p = *n;
                 *n = p->next;
         }
-        up(&block_subsys_sem);
+        mutex_unlock(&block_subsys_lock);
         kfree(p);
 
         return ret;
@@ -301,7 +302,7 @@ static void *part_start(struct seq_file *part, loff_t *pos)
         struct list_head *p;
         loff_t l = *pos;
 
-        down(&block_subsys_sem);
+        mutex_lock(&block_subsys_lock);
         list_for_each(p, &block_subsys.kset.list)
                 if (!l--)
                         return list_entry(p, struct gendisk, kobj.entry);
@@ -318,7 +319,7 @@ static void *part_next(struct seq_file *part, void *v, loff_t *pos)
 
 static void part_stop(struct seq_file *part, void *v)
 {
-        up(&block_subsys_sem);
+        mutex_unlock(&block_subsys_lock);
 }
 
 static int show_partition(struct seq_file *part, void *v)
@@ -377,7 +378,7 @@ static struct kobject *base_probe(dev_t dev, int *part, void *data)
 
 static int __init genhd_device_init(void)
 {
-        bdev_map = kobj_map_init(base_probe, &block_subsys_sem);
+        bdev_map = kobj_map_init(base_probe, &block_subsys_lock);
         blk_dev_init();
         subsystem_register(&block_subsys);
         return 0;
@@ -611,7 +612,7 @@ static void *diskstats_start(struct seq_file *part, loff_t *pos)
         loff_t k = *pos;
         struct list_head *p;
 
-        down(&block_subsys_sem);
+        mutex_lock(&block_subsys_lock);
         list_for_each(p, &block_subsys.kset.list)
                 if (!k--)
                         return list_entry(p, struct gendisk, kobj.entry);
@@ -628,7 +629,7 @@ static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
 
 static void diskstats_stop(struct seq_file *part, void *v)
 {
-        up(&block_subsys_sem);
+        mutex_unlock(&block_subsys_lock);
 }
 
 static int diskstats_show(struct seq_file *s, void *v)