Re: [Xen-devel] [PATCH 1/3] xen/pv-on-hvm kexec: add xs_introduce to shutdown watches from old kernel

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

> Index: linux-3.0/drivers/xen/xenbus/xenbus_xs.c
> ===================================================================
> --- linux-3.0.orig/drivers/xen/xenbus/xenbus_xs.c
> +++ linux-3.0/drivers/xen/xenbus/xenbus_xs.c
> @@ -620,6 +620,20 @@ static struct xenbus_watch *find_watch(c
>       return NULL;
>  }
>  
> +static int xs_introduce(const char *domid, const char *mfn, const char *port)
> +{
> +     struct kvec iov[3];
> +
> +     iov[0].iov_base = (char *)domid;
> +     iov[0].iov_len = strlen(domid) + 1;
> +     iov[1].iov_base = (char *)mfn;
> +     iov[1].iov_len = strlen(mfn) + 1;
> +     iov[2].iov_base = (char *)port;
> +     iov[2].iov_len = strlen(port) + 1;
> +
> +     return xs_error(xs_talkv(XBT_NIL, XS_INTRODUCE, iov,
> +                              ARRAY_SIZE(iov), NULL));

What should we do if this fails?

> +}
>  /* Register callback to watch this node. */
>  int register_xenbus_watch(struct xenbus_watch *watch)
>  {
> @@ -867,10 +881,11 @@ static int xenbus_thread(void *unused)
>       return 0;
>  }
>  
> -int xs_init(void)
> +int xs_init(unsigned long xen_store_mfn)
>  {
>       int err;
>       struct task_struct *task;
> +     char domid[12], mfn[24], port[24];
>  
>       INIT_LIST_HEAD(&xs_state.reply_list);
>       spin_lock_init(&xs_state.reply_lock);
> @@ -897,5 +912,15 @@ int xs_init(void)
>       if (IS_ERR(task))
>               return PTR_ERR(task);
>  
> +     snprintf(domid, sizeof(domid), "%u", DOMID_SELF);
> +     snprintf(mfn, sizeof(mfn), "%lu", xen_store_mfn);
> +     snprintf(port, sizeof(port), "%d", xen_store_evtchn);

These can be within the if, or better within the xs_introduce function
itself.

> +     if (xen_hvm_domain()) {
> +             /* shutdown watches for kexec boot */
> +             err = xs_introduce(domid, mfn, port);
> +             if (err)
> +                     printk(KERN_WARNING "xs_introduce failed: %d\n", err);
> +     }
> +
>       return 0;
>  }
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel



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