staging/lustre/llite: get rid of unused ll_super_blocks list

ll_super_blocks became unused quite a while ago with switch
to the new CLIO code.
So this patch removes the list, ll_sb_lock spinlock that guards it
and superblock info ll_list linkage.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/llite_internal.h

@@ -456,7 +456,6 @@ struct eacl_table {
 };
 
 struct ll_sb_info {
-	struct list_head		  ll_list;
 	/* this protects pglist and ra_info.  It isn't safe to
 	 * grab from interrupt contexts */
 	spinlock_t		  ll_lock;

drivers/staging/lustre/lustre/llite/llite_lib.c

@@ -60,9 +60,6 @@ struct kmem_cache *ll_file_data_slab;
 struct dentry *llite_root;
 struct kset *llite_kset;
 
-static LIST_HEAD(ll_super_blocks);
-static DEFINE_SPINLOCK(ll_sb_lock);
-
 #ifndef log2
 #define log2(n) ffz(~(n))
 #endif
@@ -112,10 +109,6 @@ static struct ll_sb_info *ll_init_sbi(struct super_block *sb)
 	class_uuid_unparse(uuid, &sbi->ll_sb_uuid);
 	CDEBUG(D_CONFIG, "generated uuid: %s\n", sbi->ll_sb_uuid.uuid);
 
-	spin_lock(&ll_sb_lock);
-	list_add_tail(&sbi->ll_list, &ll_super_blocks);
-	spin_unlock(&ll_sb_lock);
-
 	sbi->ll_flags |= LL_SBI_VERBOSE;
 	sbi->ll_flags |= LL_SBI_CHECKSUM;
 
@@ -144,12 +137,7 @@ static void ll_free_sbi(struct super_block *sb)
 {
 	struct ll_sb_info *sbi = ll_s2sbi(sb);
 
-	if (sbi != NULL) {
-		spin_lock(&ll_sb_lock);
-		list_del(&sbi->ll_list);
-		spin_unlock(&ll_sb_lock);
-		kfree(sbi);
-	}
+	kfree(sbi);
 }
 
 static int client_common_fill_super(struct super_block *sb, char *md, char *dt,