[XEN PATCH v1] xen: mem_access: conditionally compile vm_event.c & monitor.c

[Sergiy Kibrik <Sergiy_Kibrik@xxxxxxxx>]

From: Stefano Stabellini <stefano.stabellini@xxxxxxx>

Extend coverage of CONFIG_MEM_ACCESS option and make the build of VM events
and monitoring support optional.
This is to reduce code size on Arm when this option isn't enabled.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>
Signed-off-by: Sergiy Kibrik <Sergiy_Kibrik@xxxxxxxx>
---
 xen/arch/arm/Makefile      |  4 ++--
 xen/arch/arm/vsmc.c        |  3 ++-
 xen/common/Makefile        |  4 ++--
 xen/include/xen/monitor.h  |  9 +++++++++
 xen/include/xen/vm_event.h | 14 +++++++++++---
 5 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index 43ab5e8f25..8903eb0bf2 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -39,7 +39,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o
 obj-$(CONFIG_LLC_COLORING) += llc-coloring.o
 obj-$(CONFIG_MEM_ACCESS) += mem_access.o
 obj-y += mm.o
-obj-y += monitor.o
+obj-$(CONFIG_MEM_ACCESS) += monitor.o
 obj-y += p2m.o
 obj-y += platform.o
 obj-y += platform_hypercall.o
@@ -65,7 +65,7 @@ obj-$(CONFIG_VGICV2) += vgic-v2.o
 obj-$(CONFIG_GICV3) += vgic-v3.o
 obj-$(CONFIG_HAS_ITS) += vgic-v3-its.o
 endif
-obj-y += vm_event.o
+obj-$(CONFIG_MEM_ACCESS) += vm_event.o
 obj-y += vtimer.o
 obj-$(CONFIG_SBSA_VUART_CONSOLE) += vpl011.o
 obj-y += vsmc.o
diff --git a/xen/arch/arm/vsmc.c b/xen/arch/arm/vsmc.c
index 62d8117a12..1c13326bdf 100644
--- a/xen/arch/arm/vsmc.c
+++ b/xen/arch/arm/vsmc.c
@@ -330,7 +330,8 @@ void do_trap_smc(struct cpu_user_regs *regs, const union 
hsr hsr)
     }
 
     /* If monitor is enabled, let it handle the call. */
-    if ( current->domain->arch.monitor.privileged_call_enabled )
+    if ( IS_ENABLED(CONFIG_MEM_ACCESS) &&
+         current->domain->arch.monitor.privileged_call_enabled )
         rc = monitor_smc();
 
     if ( rc == 1 )
diff --git a/xen/common/Makefile b/xen/common/Makefile
index cba3b32733..e3c6a857ab 100644
--- a/xen/common/Makefile
+++ b/xen/common/Makefile
@@ -54,7 +54,7 @@ obj-y += timer.o
 obj-$(CONFIG_TRACEBUFFER) += trace.o
 obj-y += version.o
 obj-y += virtual_region.o
-obj-y += vm_event.o
+obj-$(CONFIG_MEM_ACCESS) += vm_event.o
 obj-$(CONFIG_HAS_VMAP) += vmap.o
 obj-y += vsprintf.o
 obj-y += wait.o
@@ -68,7 +68,7 @@ obj-$(CONFIG_COMPAT) += $(addprefix compat/,domain.o memory.o 
multicall.o xlat.o
 
 ifneq ($(CONFIG_PV_SHIM_EXCLUSIVE),y)
 obj-y += domctl.o
-obj-y += monitor.o
+obj-$(CONFIG_MEM_ACCESS) += monitor.o
 obj-y += sysctl.o
 endif
 
diff --git a/xen/include/xen/monitor.h b/xen/include/xen/monitor.h
index 713d54f7c1..f1359abb94 100644
--- a/xen/include/xen/monitor.h
+++ b/xen/include/xen/monitor.h
@@ -27,8 +27,17 @@
 struct domain;
 struct xen_domctl_monitor_op;
 
+#ifdef CONFIG_MEM_ACCESS
 int monitor_domctl(struct domain *d, struct xen_domctl_monitor_op *mop);
 void monitor_guest_request(void);
+#else
+static inline int monitor_domctl(struct domain *d,
+                                 struct xen_domctl_monitor_op *mop)
+{
+    return -EINVAL;
+}
+static inline void monitor_guest_request(void) {}
+#endif
 
 int monitor_traps(struct vcpu *v, bool sync, vm_event_request_t *req);
 
diff --git a/xen/include/xen/vm_event.h b/xen/include/xen/vm_event.h
index 9a86358b42..72e720e378 100644
--- a/xen/include/xen/vm_event.h
+++ b/xen/include/xen/vm_event.h
@@ -50,9 +50,6 @@ struct vm_event_domain
     unsigned int last_vcpu_wake_up;
 };
 
-/* Clean up on domain destruction */
-void vm_event_cleanup(struct domain *d);
-
 /* Returns whether a ring has been set up */
 bool vm_event_check_ring(struct vm_event_domain *ved);
 
@@ -88,7 +85,18 @@ void vm_event_cancel_slot(struct domain *d, struct 
vm_event_domain *ved);
 void vm_event_put_request(struct domain *d, struct vm_event_domain *ved,
                           vm_event_request_t *req);
 
+#ifdef CONFIG_MEM_ACCESS
+/* Clean up on domain destruction */
+void vm_event_cleanup(struct domain *d);
 int vm_event_domctl(struct domain *d, struct xen_domctl_vm_event_op *vec);
+#else
+static inline void vm_event_cleanup(struct domain *d) {}
+static inline int vm_event_domctl(struct domain *d,
+                                  struct xen_domctl_vm_event_op *vec)
+{
+    return -EINVAL;
+}
+#endif
 
 void vm_event_vcpu_pause(struct vcpu *v);
 void vm_event_vcpu_unpause(struct vcpu *v);
-- 
2.25.1