[Qemu-devel] [PATCH v7 2/4] kvm: add kvm_readonly_mem_enabled

[Jordan Justen <jordan.l.justen@intel.com>]

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
 include/sysemu/kvm.h |   10 ++++++++++
 kvm-all.c            |    6 ++++++
 kvm-stub.c           |    1 +
 3 files changed, 17 insertions(+)

diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 08284ef..8b19322 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -45,6 +45,7 @@ extern bool kvm_async_interrupts_allowed;
 extern bool kvm_irqfds_allowed;
 extern bool kvm_msi_via_irqfd_allowed;
 extern bool kvm_gsi_routing_allowed;
+extern bool kvm_readonly_mem_allowed;
 
 #if defined CONFIG_KVM || !defined NEED_CPU_H
 #define kvm_enabled()           (kvm_allowed)
@@ -97,6 +98,14 @@ extern bool kvm_gsi_routing_allowed;
  */
 #define kvm_gsi_routing_enabled() (kvm_gsi_routing_allowed)
 
+/**
+ * kvm_readonly_mem_enabled:
+ *
+ * Returns: true if KVM readonly memory is enabled (ie the kernel
+ * supports it and we're running in a configuration that permits it).
+ */
+#define kvm_readonly_mem_enabled() (kvm_readonly_mem_allowed)
+
 #else
 #define kvm_enabled()           (0)
 #define kvm_irqchip_in_kernel() (false)
@@ -104,6 +113,7 @@ extern bool kvm_gsi_routing_allowed;
 #define kvm_irqfds_enabled() (false)
 #define kvm_msi_via_irqfd_enabled() (false)
 #define kvm_gsi_routing_allowed() (false)
+#define kvm_readonly_mem_enabled() (false)
 #endif
 
 struct kvm_run;
diff --git a/kvm-all.c b/kvm-all.c
index 8222729..327ae12 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -111,6 +111,7 @@ bool kvm_irqfds_allowed;
 bool kvm_msi_via_irqfd_allowed;
 bool kvm_gsi_routing_allowed;
 bool kvm_allowed;
+bool kvm_readonly_mem_allowed;
 
 static const KVMCapabilityInfo kvm_required_capabilites[] = {
     KVM_CAP_INFO(USER_MEMORY),
@@ -1425,6 +1426,11 @@ int kvm_init(void)
         s->irq_set_ioctl = KVM_IRQ_LINE_STATUS;
     }
 
+#ifdef KVM_CAP_READONLY_MEM
+    kvm_readonly_mem_allowed =
+        (kvm_check_extension(s, KVM_CAP_READONLY_MEM) > 0);
+#endif
+
     ret = kvm_arch_init(s);
     if (ret < 0) {
         goto err;
diff --git a/kvm-stub.c b/kvm-stub.c
index b2c8f9b..22eaff0 100644
--- a/kvm-stub.c
+++ b/kvm-stub.c
@@ -26,6 +26,7 @@ bool kvm_irqfds_allowed;
 bool kvm_msi_via_irqfd_allowed;
 bool kvm_gsi_routing_allowed;
 bool kvm_allowed;
+bool kvm_readonly_mem_allowed;
 
 int kvm_init_vcpu(CPUState *cpu)
 {
-- 
1.7.10.4