1 files changed, 61 insertions, 0 deletions
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 23aeb09949..b66b936a95 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -30,6 +30,7 @@
 #include "exec/address-spaces.h"
 #include "hw/boards.h"
 #include "hw/irq.h"
+#include "qapi/visitor.h"
 #include "qemu/log.h"
 
 const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
@@ -287,6 +288,26 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         }
     }
 
+    if (s->kvm_eager_split_size) {
+        uint32_t sizes;
+
+        sizes = kvm_vm_check_extension(s, KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES);
+        if (!sizes) {
+            s->kvm_eager_split_size = 0;
+            warn_report("Eager Page Split support not available");
+        } else if (!(s->kvm_eager_split_size & sizes)) {
+            error_report("Eager Page Split requested chunk size not valid");
+            ret = -EINVAL;
+        } else {
+            ret = kvm_vm_enable_cap(s, KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE, 0,
+                                    s->kvm_eager_split_size);
+            if (ret < 0) {
+                error_report("Enabling of Eager Page Split failed: %s",
+                             strerror(-ret));
+            }
+        }
+    }
+
     kvm_arm_init_debug(s);
 
     return ret;
@@ -1069,6 +1090,46 @@ bool kvm_arch_cpu_check_are_resettable(void)
     return true;
 }
 
+static void kvm_arch_get_eager_split_size(Object *obj, Visitor *v,
+                                          const char *name, void *opaque,
+                                          Error **errp)
+{
+    KVMState *s = KVM_STATE(obj);
+    uint64_t value = s->kvm_eager_split_size;
+
+    visit_type_size(v, name, &value, errp);
+}
+
+static void kvm_arch_set_eager_split_size(Object *obj, Visitor *v,
+                                          const char *name, void *opaque,
+                                          Error **errp)
+{
+    KVMState *s = KVM_STATE(obj);
+    uint64_t value;
+
+    if (s->fd != -1) {
+        error_setg(errp, "Unable to set early-split-size after KVM has been initialized");
+        return;
+    }
+
+    if (!visit_type_size(v, name, &value, errp)) {
+        return;
+    }
+
+    if (value && !is_power_of_2(value)) {
+        error_setg(errp, "early-split-size must be a power of two");
+        return;
+    }
+
+    s->kvm_eager_split_size = value;
+}
+
 void kvm_arch_accel_class_init(ObjectClass *oc)
 {
+    object_class_property_add(oc, "eager-split-size", "size",
+                              kvm_arch_get_eager_split_size,
+                              kvm_arch_set_eager_split_size, NULL, NULL);
+
+    object_class_property_set_description(oc, "eager-split-size",
+        "Eager Page Split chunk size for hugepages. (default: 0, disabled)");
 }