Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 101 insertions, 0 deletions

diff --git a/target/i386/kvm/hyperv.c b/target/i386/kvm/hyperv.c
new file mode 100644
index 000000000..26efc1e0e
--- /dev/null
+++ b/target/i386/kvm/hyperv.c
@@ -0,0 +1,101 @@
+/*
+ * QEMU KVM Hyper-V support
+ *
+ * Copyright (C) 2015 Andrey Smetanin <asmetanin@virtuozzo.com>
+ *
+ * Authors:
+ *  Andrey Smetanin <asmetanin@virtuozzo.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "hyperv.h"
+#include "hw/hyperv/hyperv.h"
+#include "hyperv-proto.h"
+
+int hyperv_x86_synic_add(X86CPU *cpu)
+{
+    hyperv_synic_add(CPU(cpu));
+    return 0;
+}
+
+void hyperv_x86_synic_reset(X86CPU *cpu)
+{
+    hyperv_synic_reset(CPU(cpu));
+}
+
+void hyperv_x86_synic_update(X86CPU *cpu)
+{
+    CPUX86State *env = &cpu->env;
+    bool enable = env->msr_hv_synic_control & HV_SYNIC_ENABLE;
+    hwaddr msg_page_addr = (env->msr_hv_synic_msg_page & HV_SIMP_ENABLE) ?
+        (env->msr_hv_synic_msg_page & TARGET_PAGE_MASK) : 0;
+    hwaddr event_page_addr = (env->msr_hv_synic_evt_page & HV_SIEFP_ENABLE) ?
+        (env->msr_hv_synic_evt_page & TARGET_PAGE_MASK) : 0;
+    hyperv_synic_update(CPU(cpu), enable, msg_page_addr, event_page_addr);
+}
+
+static void async_synic_update(CPUState *cs, run_on_cpu_data data)
+{
+    qemu_mutex_lock_iothread();
+    hyperv_x86_synic_update(X86_CPU(cs));
+    qemu_mutex_unlock_iothread();
+}
+
+int kvm_hv_handle_exit(X86CPU *cpu, struct kvm_hyperv_exit *exit)
+{
+    CPUX86State *env = &cpu->env;
+
+    switch (exit->type) {
+    case KVM_EXIT_HYPERV_SYNIC:
+        if (!hyperv_feat_enabled(cpu, HYPERV_FEAT_SYNIC)) {
+            return -1;
+        }
+
+        switch (exit->u.synic.msr) {
+        case HV_X64_MSR_SCONTROL:
+            env->msr_hv_synic_control = exit->u.synic.control;
+            break;
+        case HV_X64_MSR_SIMP:
+            env->msr_hv_synic_msg_page = exit->u.synic.msg_page;
+            break;
+        case HV_X64_MSR_SIEFP:
+            env->msr_hv_synic_evt_page = exit->u.synic.evt_page;
+            break;
+        default:
+            return -1;
+        }
+
+        /*
+         * this will run in this cpu thread before it returns to KVM, but in a
+         * safe environment (i.e. when all cpus are quiescent) -- this is
+         * necessary because memory hierarchy is being changed
+         */
+        async_safe_run_on_cpu(CPU(cpu), async_synic_update, RUN_ON_CPU_NULL);
+
+        return 0;
+    case KVM_EXIT_HYPERV_HCALL: {
+        uint16_t code = exit->u.hcall.input & 0xffff;
+        bool fast = exit->u.hcall.input & HV_HYPERCALL_FAST;
+        uint64_t param = exit->u.hcall.params[0];
+
+        switch (code) {
+        case HV_POST_MESSAGE:
+            exit->u.hcall.result = hyperv_hcall_post_message(param, fast);
+            break;
+        case HV_SIGNAL_EVENT:
+            exit->u.hcall.result = hyperv_hcall_signal_event(param, fast);
+            break;
+        default:
+            exit->u.hcall.result = HV_STATUS_INVALID_HYPERCALL_CODE;
+        }
+        return 0;
+    }
+    default:
+        return -1;
+    }
+}