[PATCH 2/2] defaultenv: boot/net: allow customising NFS port and path

[Roland Hieber]

There are use cases where the port and mount path of the NFS root need
to be changed from the default values, e.g. with the userspace NFS
daemon used by 'ptxdist nfsroot', which tells you:

    Mount rootfs with nfsroot=/root,v3,tcp,port=13049,mountport=13049

(The port number can vary of course, depending on how many users on your
devel server have already started unfsd at the same time.)

Support such use cases by introducing two new variables for the port
number and the mount path, which get inserted into the kernel command
line. Use the old default mount path as fallback when the new variable
is not set.

Signed-off-by: Roland Hieber <rhi at pengutronix.de>
---
 Documentation/user/networking.rst     | 10 ++++++++++
 defaultenv/defaultenv-2-base/boot/net | 11 ++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/Documentation/user/networking.rst b/Documentation/user/networking.rst
index 6bd16ea8d1bd..e95957c0a26a 100644
--- a/Documentation/user/networking.rst
+++ b/Documentation/user/networking.rst
@@ -53,6 +53,16 @@ device:
 | global.net.nameserver        | ipv4 address | The DNS server used for resolving host names.         |
 |                              |              | May be set by DHCP.                                   |
 +------------------------------+--------------+-------------------------------------------------------+
+| global.net.nfspath           | string       | If set, determines the mount path of the root         |
+|                              |              | file system on the NFS server.                        |
+|                              |              | If not set, the default value                         |
+|                              |              | ``/home/${global.user}/nfsroot/${global.hostname}``   |
+|                              |              | is used.                                              |
++------------------------------+--------------+-------------------------------------------------------+
+| global.net.nfsport           | short        | If set, determines the port of the NFS server         |
+|                              |              | (the ``mountport`` and ``port`` arguments of the      |
+|                              |              | ``nfsroot`` parameter in the kernel command line).    |
++------------------------------+--------------+-------------------------------------------------------+
 | global.net.ifup_force_detect | boolean      | Set to true if your network device is not             |
 |                              |              | detected automatically during start (i.e. for         |
 |                              |              | USB network adapters).                                |
diff --git a/defaultenv/defaultenv-2-base/boot/net b/defaultenv/defaultenv-2-base/boot/net
index e79432eb277c..236955ef6fed 100644
--- a/defaultenv/defaultenv-2-base/boot/net
+++ b/defaultenv/defaultenv-2-base/boot/net
@@ -22,7 +22,16 @@ initramfs="${path}/${global.user}-initramfs-${global.hostname}"
 if [ -f "${initramfs}" ]; then
 	global.bootm.initrd="$initramfs"
 else
-	nfsroot="${nfsserver}:/home/${global.user}/nfsroot/${global.hostname}"
+	if [ -z "${global.net.nfspath}" ]; then
+		nfsroot="${nfsserver}:/home/${global.user}/nfsroot/${global.hostname}"
+	else
+		nfsroot="${nfsserver}:${global.net.nfspath}"
+	fi
+
+	if [ -n "${global.net.nfsport}" ]; then
+		nfsroot="${nfsroot},port=${global.net.nfsport},mountport=${global.net.nfsport}"
+	fi
+
 	ip_route_get -b ${global.net.server} global.linux.bootargs.dyn.ip
 	global.linux.bootargs.dyn.root="root=/dev/nfs nfsroot=$nfsroot,v3,tcp"
 fi
-- 
2.30.2