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, 123 insertions, 0 deletions

diff --git a/tests/plugin/mem.c b/tests/plugin/mem.c
new file mode 100644
index 000000000..4570f7d81
--- /dev/null
+++ b/tests/plugin/mem.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2018, Emilio G. Cota <cota@braap.org>
+ *
+ * License: GNU GPL, version 2 or later.
+ *   See the COPYING file in the top-level directory.
+ */
+#include <inttypes.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <glib.h>
+
+#include <qemu-plugin.h>
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+
+static uint64_t inline_mem_count;
+static uint64_t cb_mem_count;
+static uint64_t io_count;
+static bool do_inline, do_callback;
+static bool do_haddr;
+static enum qemu_plugin_mem_rw rw = QEMU_PLUGIN_MEM_RW;
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+    g_autoptr(GString) out = g_string_new("");
+
+    if (do_inline) {
+        g_string_printf(out, "inline mem accesses: %" PRIu64 "\n", inline_mem_count);
+    }
+    if (do_callback) {
+        g_string_append_printf(out, "callback mem accesses: %" PRIu64 "\n", cb_mem_count);
+    }
+    if (do_haddr) {
+        g_string_append_printf(out, "io accesses: %" PRIu64 "\n", io_count);
+    }
+    qemu_plugin_outs(out->str);
+}
+
+static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
+                     uint64_t vaddr, void *udata)
+{
+    if (do_haddr) {
+        struct qemu_plugin_hwaddr *hwaddr;
+        hwaddr = qemu_plugin_get_hwaddr(meminfo, vaddr);
+        if (qemu_plugin_hwaddr_is_io(hwaddr)) {
+            io_count++;
+        } else {
+            cb_mem_count++;
+        }
+    } else {
+        cb_mem_count++;
+    }
+}
+
+static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
+{
+    size_t n = qemu_plugin_tb_n_insns(tb);
+    size_t i;
+
+    for (i = 0; i < n; i++) {
+        struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i);
+
+        if (do_inline) {
+            qemu_plugin_register_vcpu_mem_inline(insn, rw,
+                                                 QEMU_PLUGIN_INLINE_ADD_U64,
+                                                 &inline_mem_count, 1);
+        }
+        if (do_callback) {
+            qemu_plugin_register_vcpu_mem_cb(insn, vcpu_mem,
+                                             QEMU_PLUGIN_CB_NO_REGS,
+                                             rw, NULL);
+        }
+    }
+}
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
+                                           const qemu_info_t *info,
+                                           int argc, char **argv)
+{
+
+    for (int i = 0; i < argc; i++) {
+        char *opt = argv[i];
+        g_autofree char **tokens = g_strsplit(opt, "=", 2);
+
+        if (g_strcmp0(tokens[0], "haddr") == 0) {
+            if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_haddr)) {
+                fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+                return -1;
+            }
+        } else if (g_strcmp0(tokens[0], "track") == 0) {
+            if (g_strcmp0(tokens[1], "r") == 0) {
+                rw = QEMU_PLUGIN_MEM_R;
+            } else if (g_strcmp0(tokens[1], "w") == 0) {
+                rw = QEMU_PLUGIN_MEM_W;
+            } else if (g_strcmp0(tokens[1], "rw") == 0) {
+                rw = QEMU_PLUGIN_MEM_RW;
+            } else {
+                fprintf(stderr, "invaild value for argument track: %s\n", opt);
+                return -1;
+            }
+        } else if (g_strcmp0(tokens[0], "inline") == 0) {
+            if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_inline)) {
+                fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+                return -1;
+            }
+        } else if (g_strcmp0(tokens[0], "callback") == 0) {
+            if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_callback)) {
+                fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+                return -1;
+            }
+        } else {
+            fprintf(stderr, "option parsing failed: %s\n", opt);
+            return -1;
+        }
+    }
+
+    qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+    qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
+    return 0;
+}