[patch] ipv4: Update ip command line processing (take II)

From: Simon Horman
Date: Tue Dec 25 2007 - 21:59:33 EST


Recently the documentation in Documentation/nfsroot.txt was
update to note that in fact ip=off and ip=::::::off as the
latter is ignored and the default (on) is used.

This was certainly a step in the direction of reducing confusion.
But it seems to me that the code ought to be fixed up so that
ip=::::::off actually turns off ip autoconfiguration.

This patch also notes more specifically that ip=on (aka ip=::::::on)
is the default.

Cc: Amos Waterland <apw@xxxxxxxxxx>
Signed-off-by: Simon Horman <horms@xxxxxxxxxxxx>

---
Fri, 21 Dec 2007 16:48:16 +0900
* Removed check on if (name) in ic_proto_name().
It should have been if (*name == '\0'), but even then its
a bit bogus, providing an early exit for a code-path that
is called approximately once.

Index: net-2.6.25/net/ipv4/ipconfig.c
===================================================================
--- net-2.6.25.orig/net/ipv4/ipconfig.c 2007-12-26 11:56:20.000000000 +0900
+++ net-2.6.25/net/ipv4/ipconfig.c 2007-12-26 11:57:04.000000000 +0900
@@ -1417,6 +1417,10 @@ static int __init ic_proto_name(char *na
if (!strcmp(name, "on") || !strcmp(name, "any")) {
return 1;
}
+ if (!strcmp(name, "off") || !strcmp(name, "none")) {
+ ic_enable = 0;
+ return 1;
+ }
#ifdef CONFIG_IP_PNP_DHCP
else if (!strcmp(name, "dhcp")) {
ic_proto_enabled &= ~IC_RARP;
@@ -1451,12 +1455,6 @@ static int __init ip_auto_config_setup(c

ic_set_manually = 1;

- ic_enable = (*addrs &&
- (strcmp(addrs, "off") != 0) &&
- (strcmp(addrs, "none") != 0));
- if (!ic_enable)
- return 1;
-
if (ic_proto_name(addrs))
return 1;

Index: net-2.6.25/Documentation/nfsroot.txt
===================================================================
--- net-2.6.25.orig/Documentation/nfsroot.txt 2007-12-26 11:56:20.000000000 +0900
+++ net-2.6.25/Documentation/nfsroot.txt 2007-12-26 11:57:04.000000000 +0900
@@ -97,10 +97,6 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netm
autoconfiguration will take place. The most common way to use this
is "ip=dhcp".

- Note that "ip=off" is not the same thing as "ip=::::::off", because in
- the latter autoconfiguration will take place if any of DHCP, BOOTP or RARP
- are compiled in the kernel.
-
<client-ip> IP address of the client.

Default: Determined using autoconfiguration.
@@ -150,6 +146,7 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netm

off or none: don't use autoconfiguration
on or any: use any protocol available in the kernel
+ (default)
dhcp: use DHCP
bootp: use BOOTP
rarp: use RARP
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/