[PATCH v2 3/7] xen/evtchn: restrict the maximum number of evtchn supported for domUs

[Rahul Singh <rahul.singh@xxxxxxx>]

Static event channel support will be added for dom0less domains.
Restrict the maximum number of evtchn supported for domUs to avoid
allocating a large amount of memory in Xen.

Signed-off-by: Rahul Singh <rahul.singh@xxxxxxx>
---
Changes in v2:
 - new patch in the version
---
---
 xen/arch/arm/domain_build.c | 2 +-
 xen/include/xen/sched.h     | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 3fd1186b53..6d447367be 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -3277,7 +3277,7 @@ void __init create_domUs(void)
         struct xen_domctl_createdomain d_cfg = {
             .arch.gic_version = XEN_DOMCTL_CONFIG_GIC_NATIVE,
             .flags = XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap,
-            .max_evtchn_port = -1,
+            .max_evtchn_port = MAX_EVTCHNS_PORT,
             .max_grant_frames = -1,
             .max_maptrack_frames = -1,
             .grant_opts = XEN_DOMCTL_GRANT_version(opt_gnttab_max_version),
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index e2b3b6daa3..e5cc4f3e3e 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -76,6 +76,9 @@ extern domid_t hardware_domid;
 /* Maximum number of event channels for any ABI. */
 #define MAX_NR_EVTCHNS MAX(EVTCHN_2L_NR_CHANNELS, EVTCHN_FIFO_NR_CHANNELS)
 
+/* Maximum number of event channels supported for domUs. */
+#define MAX_EVTCHNS_PORT 4096
+
 #define EVTCHNS_PER_BUCKET (PAGE_SIZE / next_power_of_2(sizeof(struct evtchn)))
 #define EVTCHNS_PER_GROUP  (BUCKETS_PER_GROUP * EVTCHNS_PER_BUCKET)
 #define NR_EVTCHN_GROUPS   DIV_ROUND_UP(MAX_NR_EVTCHNS, EVTCHNS_PER_GROUP)
-- 
2.25.1