Re: [PATCH] vhost-net: add module alias (v2.1)

[Stephen Hemminger <shemminger@vyatta.com>]

On Mon, 16 Jan 2012 12:26:45 +0000
Alan Cox <alan@linux.intel.com> wrote:

> > > ACKs, NACKs?  What is happening here?
> > 
> > I would like an Ack from Alan Cox who switched vhost-net
> > to a dynamic minor in the first place, in commit
> > 79907d89c397b8bc2e05b347ec94e928ea919d33.
> 
> Sorry device@lanana.org isn't yet back from the kernel hack incident.
> 
> I don't read netdev so someone needs to summarise the issue and send me
> a copy of the patch to look at.
> 
> Alan

Subject: vhost-net: add module alias (v2.1)

By adding some module aliases, programs (or users) won't have to explicitly
call modprobe. Vhost-net will always be available if built into the kernel.
It does require assigning a permanent minor number for depmod to work.

Also:
  - use C99 style initialization.
  - add missing entry in documentation for loop-control

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

---
2.1 - add missing documentation for loop control as well

 Documentation/devices.txt  |    3 +++
 drivers/vhost/net.c        |    8 +++++---
 include/linux/miscdevice.h |    1 +
 3 files changed, 9 insertions(+), 3 deletions(-)

--- a/drivers/vhost/net.c	2012-01-12 14:14:25.681815487 -0800
+++ b/drivers/vhost/net.c	2012-01-12 18:09:56.810680816 -0800
@@ -856,9 +856,9 @@ static const struct file_operations vhos
 };
 
 static struct miscdevice vhost_net_misc = {
-	MISC_DYNAMIC_MINOR,
-	"vhost-net",
-	&vhost_net_fops,
+	.minor = VHOST_NET_MINOR,
+	.name = "vhost-net",
+	.fops = &vhost_net_fops,
 };
 
 static int vhost_net_init(void)
@@ -879,3 +879,5 @@ MODULE_VERSION("0.0.1");
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Michael S. Tsirkin");
 MODULE_DESCRIPTION("Host kernel accelerator for virtio net");
+MODULE_ALIAS_MISCDEV(VHOST_NET_MINOR);
+MODULE_ALIAS("devname:vhost-net");
--- a/include/linux/miscdevice.h	2012-01-12 14:14:25.725815981 -0800
+++ b/include/linux/miscdevice.h	2012-01-12 18:09:56.810680816 -0800
@@ -42,6 +42,7 @@
 #define AUTOFS_MINOR		235
 #define MAPPER_CTRL_MINOR	236
 #define LOOP_CTRL_MINOR		237
+#define VHOST_NET_MINOR		238
 #define MISC_DYNAMIC_MINOR	255
 
 struct device;
--- a/Documentation/devices.txt	2012-01-12 14:14:25.701815712 -0800
+++ b/Documentation/devices.txt	2012-01-12 18:09:56.814680860 -0800
@@ -447,6 +447,9 @@ Your cooperation is appreciated.
 		234 = /dev/btrfs-control	Btrfs control device
 		235 = /dev/autofs	Autofs control device
 		236 = /dev/mapper/control	Device-Mapper control device
+		237 = /dev/loop-control Loopback control device
+		238 = /dev/vhost-net	Host kernel accelerator for virtio net
+
 		240-254			Reserved for local use
 		255			Reserved for MISC_DYNAMIC_MINOR