ipconfig wait for carrier

v3 -> v4: fix return boolean false instead of 0 for ic_is_init_dev

Currently the ip auto configuration has a hardcoded delay of 1 second.
When (ethernet) link takes longer to come up (e.g. more than 3 seconds),
nfs root may not be found.

Remove the hardcoded delay, and wait for carrier on at least one network
device.

Signed-off-by: Micha Nelissen <micha@neli.hopto.org>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 22 insertions, 13 deletions

diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index cbff2ecccf3d..ab7e5542c1cf 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -87,8 +87,8 @@
 #endif
 
 /* Define the friendly delay before and after opening net devices */
-#define CONF_PRE_OPEN           500     /* Before opening: 1/2 second */
-#define CONF_POST_OPEN          1       /* After opening: 1 second */
+#define CONF_POST_OPEN          10      /* After opening: 10 msecs */
+#define CONF_CARRIER_TIMEOUT    120000  /* Wait for carrier timeout */
 
 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
@@ -188,14 +188,14 @@ struct ic_device {
 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
 static struct net_device *ic_dev __initdata = NULL;     /* Selected device */
 
-static bool __init ic_device_match(struct net_device *dev)
+static bool __init ic_is_init_dev(struct net_device *dev)
 {
-        if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
+        if (dev->flags & IFF_LOOPBACK)
+                return false;
+        return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
             (!(dev->flags & IFF_LOOPBACK) &&
              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
-             strncmp(dev->name, "dummy", 5)))
-                return true;
-        return false;
+             strncmp(dev->name, "dummy", 5));
 }
 
 static int __init ic_open_devs(void)
@@ -203,6 +203,7 @@ static int __init ic_open_devs(void)
         struct ic_device *d, **last;
         struct net_device *dev;
         unsigned short oflags;
+        unsigned long start;
 
         last = &ic_first_dev;
         rtnl_lock();
@@ -216,9 +217,7 @@ static int __init ic_open_devs(void)
         }
 
         for_each_netdev(&init_net, dev) {
-                if (dev->flags & IFF_LOOPBACK)
-                        continue;
-                if (ic_device_match(dev)) {
+                if (ic_is_init_dev(dev)) {
                         int able = 0;
                         if (dev->mtu >= 364)
                                 able |= IC_BOOTP;
@@ -252,6 +251,17 @@ static int __init ic_open_devs(void)
                                 dev->name, able, d->xid));
                 }
         }
+
+        /* wait for a carrier on at least one device */
+        start = jiffies;
+        while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
+                for_each_netdev(&init_net, dev)
+                        if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
+                                goto have_carrier;
+
+                msleep(1);
+        }
+have_carrier:
         rtnl_unlock();
 
         *last = NULL;
@@ -1324,14 +1334,13 @@ static int __init wait_for_devices(void)
 {
         int i;
 
-        msleep(CONF_PRE_OPEN);
         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
                 struct net_device *dev;
                 int found = 0;
 
                 rtnl_lock();
                 for_each_netdev(&init_net, dev) {
-                        if (ic_device_match(dev)) {
+                        if (ic_is_init_dev(dev)) {
                                 found = 1;
                                 break;
                         }
@@ -1378,7 +1387,7 @@ static int __init ip_auto_config(void)
                 return err;
 
         /* Give drivers a chance to settle */
-        ssleep(CONF_POST_OPEN);
+        msleep(CONF_POST_OPEN);
 
         /*
          * If the config information is insufficient (e.g., our IP address or