monitor: an interface of acrn-dm

A monitor component will be added to acrn-dm, which crteats socket,
bind and listening at /run/acrn/vmname. Acrnctl & acrnd could conn
-ect to the socket for communication, using defined message, in
include/monitor_msg.h
For each defined message, a message handler callback could be
registered via monitor_add_msg_handler(). On received of a defined
message, a certain call back will be called. Each callback can only
see the message sender's socket-fd.
When acrn-dm want report something, not triggered by incoming message
it can send broadcast message, use monitor_broadcast().

Acked-by: Eddie Dong <eddie.dong@intel.com>
Reviewed-by: Geoffroy Van Cutsem <geoffroy.vancutsem@intel.com>
Reviewed-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Yin, Fengwei <fengwei.yin@intel.com>
Signed-off-by: Tao, Yuhong <yuhong.tao@intel.com>

include/monitor_msg.h

@@ -0,0 +1,107 @@
+/*
+ * Project Acrn
+ * Acrn-dm-monitor
+ *
+ * Copyright (C) 2018 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ *   * Neither the name of Intel Corporation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * Author: TaoYuhong <yuhong.tao@intel.com>
+ */
+
+/* this file will be shared, by anyone who want talk to acrn-dm */
+#ifndef MONITOR_MSG_H
+#define MONITOR_MSG_H
+
+enum msgid {
+	REQ_STARTALL = 0,	/* SOS lifecycle service -> VM Mngr */
+	REQ_PAUSEALL,		/* SOS lifecycle service -> VM Mngr */
+	REQ_START,		/* VM Mngr -> ACRN-DM(vm) */
+	REQ_STOP,		/* VM Mngr -> ACRN-DM(vm) */
+	REQ_PAUSE,
+	REQ_RESUME,		/* VM Mngr -> ACRN-DM(vm) */
+	REQ_RESET,
+	REQ_QUERY,
+	NTF_ALLSTOPPED,		/* VM Mngr -> SOS lifecycle service */
+	NTF_ALLPAUSED,		/* VM Mngr -> SOS lifecycle service */
+	NTF_STARTED,		/* ACRN-DM -> VM Mngr */
+	NTF_STOPPED,		/* ACRN-DM -> VM Mngr */
+	NTF_PAUSED,		/* ACRN-DM -> VM Mngr */
+	NTF_RESUMED,		/* ACRN-DM -> VM Mngr */
+
+	MSG_STR,
+	MSG_HANDSHAKE,		/* handshake */
+
+	MSGID_MAX
+};
+
+#define VMM_MSG_MAGIC	0x67736d206d6d76	/* that is char[8] "vmm msg", on X86 */
+#define VMM_MSG_MAX_LEN		4096
+
+struct vmm_msg {
+	unsigned long long magic;	/* Make sure you get a vmm_msg */
+	unsigned int msgid;
+	unsigned long timestamp;
+	size_t len;		/* vmm_msg + payload size */
+	char payload[0];
+};
+
+/* practical messages, and helpers
+ *  each message defined in msgid should have its own data structure,
+ *  and shared by acrn-dm and vm-mngr. So that such that message data 
+ *  structure can be recognized by both sides of the communication
+ */
+
+/* For test, generate a message who carry a string
+ * eg., VMM_MSG_STR(hello_msg, "Hello\n") will create hello_msg,
+ * then you can write(sock_fd, hello_msg, sizeof(hello_msg))
+ */
+#define VMM_MSG_STR(var, str)	\
+struct vmm_msg_##var {		\
+struct vmm_msg vmsg;		\
+        char raw[sizeof(str)];		\
+} var = {				\
+        .vmsg = {			\
+                .magic = VMM_MSG_MAGIC,	\
+                .msgid = MSG_STR,	\
+                .len = sizeof(struct vmm_msg_##var),	\
+        },						\
+        .raw = str,				\
+}
+
+#define CLIENT_NAME_LEN	16
+struct vmm_msg_handshake {
+	struct vmm_msg vmsg;
+	char name[CLIENT_NAME_LEN];	/* name should be a string, end with '\0' */
+	/* can be "acrnd", "vm-mngr" or "acrnctl" */
+	int broadcast;		/* if set, allow acrn-dm send broadcast */
+	/*   message to such client */
+};
+
+#endif