Add DOMCTL to limit the number of event channels a domain may use

Add XEN_DOMCTL_set_max_evtchn which may be used during domain creation to
set the maximum event channel port a domain may use.  This may be used to
limit the amount of Xen resources (global mapping space and xenheap) that
a domain may use for event channels.

A domain that does not have a limit set may use all the event channels
supported by the event channel ABI in use.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Keir Fraser <keir@xen.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index ca7e41712d..c2588a5f86 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -291,6 +291,7 @@ struct domain
     struct evtchn   *evtchn;                         /* first bucket only */
     struct evtchn  **evtchn_group[NR_EVTCHN_GROUPS]; /* all other buckets */
     unsigned int     max_evtchns;
+    unsigned int     max_evtchn_port;
     spinlock_t       event_lock;
     const struct evtchn_port_ops *evtchn_port_ops;
     struct evtchn_fifo_domain *evtchn_fifo;