staging/lustre/llite: remove llite proc root on init failure

In init_lustre_lite() ensure that /proc/fs/lustre/llite is removed in
case of failure. Generally rework the cleanup code in this function.
Signed-off-by: John L. Hammond <john.hammond@intel.com>
Reviewed-on: http://review.whamcloud.com/6420
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3331Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/super25.c

@@ -72,21 +72,6 @@ static void ll_destroy_inode(struct inode *inode)
 	call_rcu(&inode->i_rcu, ll_inode_destroy_callback);
 }
 
-static int ll_init_inodecache(void)
-{
-	ll_inode_cachep = kmem_cache_create("lustre_inode_cache",
-					       sizeof(struct ll_inode_info),
-					       0, SLAB_HWCACHE_ALIGN, NULL);
-	if (ll_inode_cachep == NULL)
-		return -ENOMEM;
-	return 0;
-}
-
-static void ll_destroy_inodecache(void)
-{
-	kmem_cache_destroy(ll_inode_cachep);
-}
-
 /* exported operations */
 struct super_operations lustre_super_operations = {
 	.alloc_inode   = ll_alloc_inode,
@@ -104,9 +89,10 @@ void lustre_register_client_process_config(int (*cpc)(struct lustre_cfg *lcfg));
 
 static int __init init_lustre_lite(void)
 {
-	int i, rc, seed[2];
-	struct timeval tv;
+	struct proc_dir_entry *entry;
 	lnet_process_id_t lnet_id;
+	struct timeval tv;
+	int i, rc, seed[2];
 
 	CLASSERT(sizeof(LUSTRE_VOLATILE_HDR) == LUSTRE_VOLATILE_HDR_LEN + 1);
 
@@ -116,60 +102,53 @@ static int __init init_lustre_lite(void)
 	CDEBUG(D_INFO, "Lustre client module (%p).\n",
 	       &lustre_super_operations);
 
-	rc = ll_init_inodecache();
-	if (rc)
-		return -ENOMEM;
+	rc = -ENOMEM;
+	ll_inode_cachep = kmem_cache_create("lustre_inode_cache",
+					    sizeof(struct ll_inode_info),
+					    0, SLAB_HWCACHE_ALIGN, NULL);
+	if (ll_inode_cachep == NULL)
+		goto out_cache;
+
 	ll_file_data_slab = kmem_cache_create("ll_file_data",
 						 sizeof(struct ll_file_data), 0,
 						 SLAB_HWCACHE_ALIGN, NULL);
-	if (ll_file_data_slab == NULL) {
-		ll_destroy_inodecache();
-		return -ENOMEM;
-	}
+	if (ll_file_data_slab == NULL)
+		goto out_cache;
 
 	ll_remote_perm_cachep = kmem_cache_create("ll_remote_perm_cache",
 						  sizeof(struct ll_remote_perm),
 						      0, 0, NULL);
-	if (ll_remote_perm_cachep == NULL) {
-		kmem_cache_destroy(ll_file_data_slab);
-		ll_file_data_slab = NULL;
-		ll_destroy_inodecache();
-		return -ENOMEM;
-	}
+	if (ll_remote_perm_cachep == NULL)
+		goto out_cache;
 
 	ll_rmtperm_hash_cachep = kmem_cache_create("ll_rmtperm_hash_cache",
 						   REMOTE_PERM_HASHSIZE *
 						   sizeof(struct list_head),
 						   0, 0, NULL);
-	if (ll_rmtperm_hash_cachep == NULL) {
-		kmem_cache_destroy(ll_remote_perm_cachep);
-		ll_remote_perm_cachep = NULL;
-		kmem_cache_destroy(ll_file_data_slab);
-		ll_file_data_slab = NULL;
-		ll_destroy_inodecache();
-		return -ENOMEM;
+	if (ll_rmtperm_hash_cachep == NULL)
+		goto out_cache;
+
+	entry = lprocfs_register("llite", proc_lustre_root, NULL, NULL);
+	if (IS_ERR(entry)) {
+		rc = PTR_ERR(entry);
+		CERROR("cannot register '/proc/fs/lustre/llite': rc = %d\n",
+		       rc);
+		goto out_cache;
 	}
 
-	proc_lustre_fs_root = proc_lustre_root ?
-			      lprocfs_register("llite", proc_lustre_root, NULL, NULL) : NULL;
-
-	lustre_register_client_fill_super(ll_fill_super);
-	lustre_register_kill_super_cb(ll_kill_super);
-
-	lustre_register_client_process_config(ll_process_config);
+	proc_lustre_fs_root = entry;
 
 	cfs_get_random_bytes(seed, sizeof(seed));
 
-	/* Nodes with small feet have little entropy
-	 * the NID for this node gives the most entropy in the low bits */
-	for (i = 0; ; i++) {
-		if (LNetGetId(i, &lnet_id) == -ENOENT) {
+	/* Nodes with small feet have little entropy. The NID for this
+	 * node gives the most entropy in the low bits */
+	for (i = 0;; i++) {
+		if (LNetGetId(i, &lnet_id) == -ENOENT)
 			break;
-		}
-		if (LNET_NETTYP(LNET_NIDNET(lnet_id.nid)) != LOLND) {
+
+		if (LNET_NETTYP(LNET_NIDNET(lnet_id.nid)) != LOLND)
 			seed[0] ^= LNET_NIDADDR(lnet_id.nid);
 	}
-	}
 
 	do_gettimeofday(&tv);
 	cfs_srand(tv.tv_sec ^ seed[0], tv.tv_usec ^ seed[1]);
@@ -177,20 +156,54 @@ static int __init init_lustre_lite(void)
 	init_timer(&ll_capa_timer);
 	ll_capa_timer.function = ll_capa_timer_callback;
 	rc = ll_capa_thread_start();
-	/*
-	 * XXX normal cleanup is needed here.
-	 */
-	if (rc == 0)
+	if (rc != 0)
+		goto out_proc;
+
 	rc = vvp_global_init();
+	if (rc != 0)
+		goto out_capa;
 
-	if (rc == 0)
 	rc = ll_xattr_init();
+	if (rc != 0)
+		goto out_vvp;
+
+	lustre_register_client_fill_super(ll_fill_super);
+	lustre_register_kill_super_cb(ll_kill_super);
+	lustre_register_client_process_config(ll_process_config);
+
+	return 0;
+
+out_vvp:
+	vvp_global_fini();
+out_capa:
+	del_timer(&ll_capa_timer);
+	ll_capa_thread_stop();
+out_proc:
+	lprocfs_remove(&proc_lustre_fs_root);
+out_cache:
+	if (ll_inode_cachep != NULL)
+		kmem_cache_destroy(ll_inode_cachep);
+
+	if (ll_file_data_slab != NULL)
+		kmem_cache_destroy(ll_file_data_slab);
+
+	if (ll_remote_perm_cachep != NULL)
+		kmem_cache_destroy(ll_remote_perm_cachep);
+
+	if (ll_rmtperm_hash_cachep != NULL)
+		kmem_cache_destroy(ll_rmtperm_hash_cachep);
 
 	return rc;
 }
 
 static void __exit exit_lustre_lite(void)
 {
+	lustre_register_client_fill_super(NULL);
+	lustre_register_kill_super_cb(NULL);
+	lustre_register_client_process_config(NULL);
+
+	lprocfs_remove(&proc_lustre_fs_root);
+
 	ll_xattr_fini();
 	vvp_global_fini();
 	del_timer(&ll_capa_timer);
@@ -199,22 +212,12 @@ static void __exit exit_lustre_lite(void)
 		 "client remaining capa count %d\n",
 		 capa_count[CAPA_SITE_CLIENT]);
 
-	lustre_register_client_fill_super(NULL);
-	lustre_register_kill_super_cb(NULL);
-
-	lustre_register_client_process_config(NULL);
-
-	ll_destroy_inodecache();
-
+	kmem_cache_destroy(ll_inode_cachep);
 	kmem_cache_destroy(ll_rmtperm_hash_cachep);
-	ll_rmtperm_hash_cachep = NULL;
 
 	kmem_cache_destroy(ll_remote_perm_cachep);
-	ll_remote_perm_cachep = NULL;
 
 	kmem_cache_destroy(ll_file_data_slab);
-	if (proc_lustre_fs_root && !IS_ERR(proc_lustre_fs_root))
-		lprocfs_remove(&proc_lustre_fs_root);
 }
 
 MODULE_AUTHOR("Sun Microsystems, Inc. <http://www.lustre.org/>");