[NET]: Convert RTNL to mutex.

This patch turns the RTNL from a semaphore to a new 2.6.16 mutex and
gets rid of some of the leftover legacy.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 26 insertions, 20 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 8763c99fcb84..be1d896cc5b9 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2466,9 +2466,9 @@ int dev_ioctl(unsigned int cmd, void __user *arg)
          */
 
         if (cmd == SIOCGIFCONF) {
-                rtnl_shlock();
+                rtnl_lock();
                 ret = dev_ifconf((char __user *) arg);
-                rtnl_shunlock();
+                rtnl_unlock();
                 return ret;
         }
         if (cmd == SIOCGIFNAME)
@@ -2877,7 +2877,7 @@ static void netdev_wait_allrefs(struct net_device *dev)
         rebroadcast_time = warning_time = jiffies;
         while (atomic_read(&dev->refcnt) != 0) {
                 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
-                        rtnl_shlock();
+                        rtnl_lock();
 
                         /* Rebroadcast unregister notification */
                         notifier_call_chain(&netdev_chain,
@@ -2894,7 +2894,7 @@ static void netdev_wait_allrefs(struct net_device *dev)
                                 linkwatch_run_queue();
                         }
 
-                        rtnl_shunlock();
+                        __rtnl_unlock();
 
                         rebroadcast_time = jiffies;
                 }
diff --git a/net/core/link_watch.c b/net/core/link_watch.c
index e82a451d330b..341de44c7ed1 100644
--- a/net/core/link_watch.c
+++ b/net/core/link_watch.c
@@ -139,9 +139,9 @@ static void linkwatch_event(void *dummy)
         linkwatch_nextevent = jiffies + HZ;
         clear_bit(LW_RUNNING, &linkwatch_flags);
 
-        rtnl_shlock();
+        rtnl_lock();
         linkwatch_run_queue();
-        rtnl_shunlock();
+        rtnl_unlock();
 }
 
 
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index ea51f8d02eb8..e8e05cebd95a 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -669,14 +669,14 @@ int netpoll_setup(struct netpoll *np)
                 printk(KERN_INFO "%s: device %s not up yet, forcing it\n",
                        np->name, np->dev_name);
 
-                rtnl_shlock();
+                rtnl_lock();
                 if (dev_change_flags(ndev, ndev->flags | IFF_UP) < 0) {
                         printk(KERN_ERR "%s: failed to open %s\n",
                                np->name, np->dev_name);
-                        rtnl_shunlock();
+                        rtnl_unlock();
                         goto release;
                 }
-                rtnl_shunlock();
+                rtnl_unlock();
 
                 atleast = jiffies + HZ/10;
                 atmost = jiffies + 4*HZ;
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 1c15a907066f..ae10d3740faa 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -35,6 +35,7 @@
 #include <linux/skbuff.h>
 #include <linux/init.h>
 #include <linux/security.h>
+#include <linux/mutex.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -51,25 +52,31 @@
 #include <net/pkt_sched.h>
 #include <net/netlink.h>
 
-DECLARE_MUTEX(rtnl_sem);
+static DEFINE_MUTEX(rtnl_mutex);
 
 void rtnl_lock(void)
 {
-        rtnl_shlock();
+        mutex_lock(&rtnl_mutex);
 }
 
-int rtnl_lock_interruptible(void)
+void __rtnl_unlock(void)
 {
-        return down_interruptible(&rtnl_sem);
+        mutex_unlock(&rtnl_mutex);
 }
- 
+
 void rtnl_unlock(void)
 {
-        rtnl_shunlock();
-
+        mutex_unlock(&rtnl_mutex);
+        if (rtnl && rtnl->sk_receive_queue.qlen)
+                rtnl->sk_data_ready(rtnl, 0);
         netdev_run_todo();
 }
 
+int rtnl_trylock(void)
+{
+        return mutex_trylock(&rtnl_mutex);
+}
+
 int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
 {
         memset(tb, 0, sizeof(struct rtattr*)*maxattr);
@@ -625,9 +632,9 @@ static void rtnetlink_rcv(struct sock *sk, int len)
         unsigned int qlen = 0;
 
         do {
-                rtnl_lock();
+                mutex_lock(&rtnl_mutex);
                 netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
-                up(&rtnl_sem);
+                mutex_unlock(&rtnl_mutex);
 
                 netdev_run_todo();
         } while (qlen);
@@ -704,6 +711,5 @@ EXPORT_SYMBOL(rtnetlink_links);
 EXPORT_SYMBOL(rtnetlink_put_metrics);
 EXPORT_SYMBOL(rtnl);
 EXPORT_SYMBOL(rtnl_lock);
-EXPORT_SYMBOL(rtnl_lock_interruptible);
-EXPORT_SYMBOL(rtnl_sem);
+EXPORT_SYMBOL(rtnl_trylock);
 EXPORT_SYMBOL(rtnl_unlock);