[PATCH] gendisks list switched to list_head

The list used to generate /proc/partitions turned into list_head one;
we also restore the old order of elements (originally we added to the end
of list; recent changes had reverted that, now we are back to original
order).

drivers/block/genhd.c

@@ -31,7 +31,7 @@ static rwlock_t gendisk_lock;
 /*
  * Global kernel list of partitioning information.
  */
-static struct gendisk *gendisk_head;
+static LIST_HEAD(gendisk_list);
 
 /*
  *  TEMPORARY KLUDGE.
@@ -75,8 +75,10 @@ static void add_gendisk(struct gendisk *gp)
 
 	write_lock(&gendisk_lock);
 	list_add(&gp->list, &gendisks[gp->major].list);
-	gp->next = gendisk_head;
-	gendisk_head = gp;
+	if (gp->minor_shift)
+		list_add_tail(&gp->full_list, &gendisk_list);
+	else
+		INIT_LIST_HEAD(&gp->full_list);
 	write_unlock(&gendisk_lock);
 }
 
@@ -92,13 +94,8 @@ EXPORT_SYMBOL(del_gendisk);
 
 void unlink_gendisk(struct gendisk *disk)
 {
-	struct gendisk **p;
 	write_lock(&gendisk_lock);
-	for (p = &gendisk_head; *p; p = &((*p)->next))
-		if (*p == disk)
-			break;
-	if (*p)
-		*p = (*p)->next;
+	list_del_init(&disk->full_list);
 	list_del_init(&disk->list);
 	write_unlock(&gendisk_lock);
 }
@@ -143,21 +140,21 @@ EXPORT_SYMBOL(get_gendisk);
 /* iterator */
 static void *part_start(struct seq_file *part, loff_t *pos)
 {
-	loff_t k = *pos;
-	struct gendisk *sgp;
+	struct list_head *p;
+	loff_t l = *pos;
 
 	read_lock(&gendisk_lock);
-	for (sgp = gendisk_head; sgp; sgp = sgp->next) {
-		if (!k--)
-			return sgp;
-	}
+	list_for_each(p, &gendisk_list)
+		if (!l--)
+			return list_entry(p, struct gendisk, full_list);
 	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;
 	++*pos;
-	return ((struct gendisk *)v)->next;
+	return p==&gendisk_list ? NULL : list_entry(p, struct gendisk, full_list);
 }
 
 static void part_stop(struct seq_file *part, void *v)
@@ -171,11 +168,11 @@ static int show_partition(struct seq_file *part, void *v)
 	int n;
 	char buf[64];
 
-	if (sgp == gendisk_head)
+	if (&sgp->full_list == gendisk_list.next)
 		seq_puts(part, "major minor  #blocks  name\n\n");
 
 	/* Don't show non-partitionable devices or empty devices */
-	if (!sgp->minor_shift || !get_capacity(sgp))
+	if (!get_capacity(sgp))
 		return 0;
 
 	/* show the full disk and all non-0 size partitions of it */

include/linux/genhd.h

@@ -78,10 +78,10 @@ struct gendisk {
 					   get real minor */
 
 	struct hd_struct *part;		/* [indexed by minor] */
-	struct gendisk *next;
 	struct block_device_operations *fops;
 	sector_t capacity;
 	struct list_head list;
+	struct list_head full_list;
 
 	int flags;
 	int number;			/* devfs crap */