tipc: initiate media type array at compile time

Communication media types are abstracted through the struct 'tipc_media',
one per media type. These structs are allocated statically inside their
respective media file.

Furthermore, in order to be able to reach all instances from a central
location, we keep a static array with pointers to these structs. This
array is currently initialized at runtime, under protection of
tipc_net_lock. However, since the contents of the array itself never
changes after initialization, we can just as well initialize it at
compile time and make it 'const', at the same time making it obvious
that no lock protection is needed here.

This commit makes the array constant and removes the redundant lock
protection.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 47 deletions

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index c2101c0bfd6d..826aa9fdf45f 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -1,7 +1,7 @@
 /*
  * net/tipc/bearer.c: TIPC bearer code
  *
- * Copyright (c) 1996-2006, Ericsson AB
+ * Copyright (c) 1996-2006, 2013, Ericsson AB
  * Copyright (c) 2004-2006, 2010-2011, Wind River Systems
  * All rights reserved.
  *
@@ -41,8 +41,13 @@
 
 #define MAX_ADDR_STR 60
 
-static struct tipc_media *media_list[MAX_MEDIA];
-static u32 media_count;
+static struct tipc_media * const media_list[] = {
+	&eth_media_info,
+#ifdef CONFIG_TIPC_MEDIA_IB
+	&ib_media_info,
+#endif
+	NULL
+};
 
 struct tipc_bearer tipc_bearers[MAX_BEARERS];
 
@@ -55,11 +60,11 @@ struct tipc_media *tipc_media_find(const char *name)
 {
 	u32 i;
 
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		if (!strcmp(media_list[i]->name, name))
-			return media_list[i];
+			break;
 	}
-	return NULL;
+	return media_list[i];
 }
 
 /**
@@ -69,44 +74,11 @@ static struct tipc_media *media_find_id(u8 type)
 {
 	u32 i;
 
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		if (media_list[i]->type_id == type)
-			return media_list[i];
+			break;
 	}
-	return NULL;
-}
-
-/**
- * tipc_register_media - register a media type
- *
- * Bearers for this media type must be activated separately at a later stage.
- */
-int tipc_register_media(struct tipc_media *m_ptr)
-{
-	int res = -EINVAL;
-
-	write_lock_bh(&tipc_net_lock);
-
-	if ((strlen(m_ptr->name) + 1) > TIPC_MAX_MEDIA_NAME)
-		goto exit;
-	if (m_ptr->priority > TIPC_MAX_LINK_PRI)
-		goto exit;
-	if ((m_ptr->tolerance < TIPC_MIN_LINK_TOL) ||
-	    (m_ptr->tolerance > TIPC_MAX_LINK_TOL))
-		goto exit;
-	if (media_count >= MAX_MEDIA)
-		goto exit;
-	if (tipc_media_find(m_ptr->name) || media_find_id(m_ptr->type_id))
-		goto exit;
-
-	media_list[media_count] = m_ptr;
-	media_count++;
-	res = 0;
-exit:
-	write_unlock_bh(&tipc_net_lock);
-	if (res)
-		pr_warn("Media <%s> registration error\n", m_ptr->name);
-	return res;
+	return media_list[i];
 }
 
 /**
@@ -144,13 +116,11 @@ struct sk_buff *tipc_media_get_names(void)
 	if (!buf)
 		return NULL;
 
-	read_lock_bh(&tipc_net_lock);
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME,
 				    media_list[i]->name,
 				    strlen(media_list[i]->name) + 1);
 	}
-	read_unlock_bh(&tipc_net_lock);
 	return buf;
 }
 
@@ -247,7 +217,7 @@ struct sk_buff *tipc_bearer_get_names(void)
 		return NULL;
 
 	read_lock_bh(&tipc_net_lock);
-	for (i = 0; i < media_count; i++) {
+	for (i = 0; media_list[i] != NULL; i++) {
 		for (j = 0; j < MAX_BEARERS; j++) {
 			b_ptr = &tipc_bearers[j];
 			if (b_ptr->active && (b_ptr->media == media_list[i])) {
@@ -472,5 +442,4 @@ void tipc_bearer_stop(void)
 		if (tipc_bearers[i].active)
 			bearer_disable(&tipc_bearers[i]);
 	}
-	media_count = 0;
 }