From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: event notification
Date: Mon, 8 Mar 2010 11:47:29 -0500
Message-ID: <20100308164727.GA4568@phenom.dumpdata.com>
References: <dfc283f41003061912g7a5de86dh5d29fb601ea101f8@mail.gmail.com>
Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="d6Gm4EdcadzBjdND"
Return-path: <xen-devel-bounces@lists.xensource.com>
Content-Disposition: inline
In-Reply-To: <dfc283f41003061912g7a5de86dh5d29fb601ea101f8@mail.gmail.com>
List-Unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: ravi kerur <rkerur@gmail.com>
Cc: xen-devel@lists.xensource.com
List-Id: xen-devel@lists.xenproject.org


--d6Gm4EdcadzBjdND
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline

On Sat, Mar 06, 2010 at 07:12:02PM -0800, ravi kerur wrote:
> Hi,
> 
> Is there a mechanism available in Xen such that a kernel module in dom0 can
> register to it and when a VM(domU) is installed or deleted or suspend or
> resumed kernel module in domU can send notification to its counterpart in
> dom0. I have looked into xenbus mechanism used by PV drivers and it won't
> work for us. Inputs appreciated.

You can listen on udev events and see when a vif device has been added.
Also you can add pieces to the dom0 kernel to send uevents when a device
is suspended and do something.

Attached is a simple program to listen to all uevents..

> 
> Thanks
> -RK

> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel


--d6Gm4EdcadzBjdND
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment; filename="listen.c"

#include <sys/socket.h>
#include <linux/netlink.h>
#include <stdio.h>
#include <string.h>
#define MAX_PAYLOAD 1024        /* maximum payload size */
struct sockaddr_nl src_addr;
int sock_fd;
static char buff[MAX_PAYLOAD];
ssize_t buflen;

int
main ()
{
  sock_fd = socket (PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);

  memset (&src_addr, 0, sizeof (src_addr));
  src_addr.nl_family = AF_NETLINK;
  src_addr.nl_pid = getpid ();  /* self pid */
  src_addr.nl_groups = 0xffffffff;

  printf ("Listen..\n");
  bind (sock_fd, (struct sockaddr *) &src_addr, sizeof (src_addr));
  printf ("Receiving..\n");
  while (1)
    {
      buflen = recv (sock_fd, &buff, sizeof (buff), 0);
      printf ("Got data: %d\n", buflen);
      int i, bufpos;
      char *key;
      for (i = 0, bufpos = 0; (bufpos < buflen) && i < MAX_PAYLOAD; i++)
        {
          key = &buff[bufpos];
          printf ("[%s]\n", key);
          bufpos += strlen (key) + 1;
        }
      memset (&buff, 0, MAX_PAYLOAD);
    }
  /* Close Netlink Socket */
  close (sock_fd);
  return 0;
}

--d6Gm4EdcadzBjdND
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

--d6Gm4EdcadzBjdND--