Staging: hv: Added new hv_utils driver with shutdown as first functionality

Addition of new driver for Hyper-V called hv_utils.
This driver is intended to support things like KVP, Timesync, Heartbeat etc.

This first release has support for Gracefull shutdown.
e.g. Select shutdown from the Hyper-V main admin screen and the Linux VM
will do a gracefull shutdown.

Signed-off-by: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 134 insertions, 0 deletions

diff --git a/drivers/staging/hv/hyperv_utils.c b/drivers/staging/hv/hyperv_utils.c
new file mode 100644
index 000000000000..2a4864784edc
--- /dev/null
+++ b/drivers/staging/hv/hyperv_utils.c
@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2010, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/version.h>
+
+#include "logging.h"
+#include "osd.h"
+#include "vmbus.h"
+#include "VmbusPacketFormat.h"
+#include "VmbusChannelInterface.h"
+#include "VersionInfo.h"
+#include "Channel.h"
+#include "VmbusPrivate.h"
+#include "VmbusApi.h"
+#include "utils.h"
+
+
+void shutdown_onchannelcallback(void *context)
+{
+	struct vmbus_channel *channel = context;
+	u8 *buf;
+	u32 buflen, recvlen;
+	u64 requestid;
+	u8  execute_shutdown = false;
+
+	struct shutdown_msg_data *shutdown_msg;
+
+	struct icmsg_hdr *icmsghdrp;
+	struct icmsg_negotiate *negop = NULL;
+
+	DPRINT_ENTER(VMBUS);
+
+	buflen = PAGE_SIZE;
+	buf = kmalloc(buflen, GFP_ATOMIC);
+
+	VmbusChannelRecvPacket(channel, buf, buflen, &recvlen, &requestid);
+
+	if (recvlen > 0) {
+		DPRINT_DBG(VMBUS, "shutdown packet: len=%d, requestid=%lld",
+			   recvlen, requestid);
+
+		icmsghdrp = (struct icmsg_hdr *)&buf[
+			sizeof(struct vmbuspipe_hdr)];
+
+		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+			prep_negotiate_resp(icmsghdrp, negop, buf);
+		} else {
+			shutdown_msg = (struct shutdown_msg_data *)&buf[
+				sizeof(struct vmbuspipe_hdr) +
+				sizeof(struct icmsg_hdr)];
+
+			switch (shutdown_msg->flags) {
+			case 0:
+			case 1:
+				icmsghdrp->status = HV_S_OK;
+				execute_shutdown = true;
+
+				DPRINT_INFO(VMBUS, "Shutdown request received -"
+					    " gracefull shutdown initiated");
+				break;
+			default:
+				icmsghdrp->status = HV_E_FAIL;
+				execute_shutdown = false;
+
+				DPRINT_INFO(VMBUS, "Shutdown request received -"
+					    " Invalid request");
+				break;
+			};
+		}
+
+		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+			| ICMSGHDRFLAG_RESPONSE;
+
+		VmbusChannelSendPacket(channel, buf,
+				       recvlen, requestid,
+				       VmbusPacketTypeDataInBand, 0);
+	}
+
+	kfree(buf);
+
+	DPRINT_EXIT(VMBUS);
+
+	if (execute_shutdown == true)
+		shutdown_linux_system();
+}
+
+static int __init init_hyperv_utils(void)
+{
+	printk(KERN_INFO "Registering HyperV Utility Driver\n");
+
+	hv_cb_utils[HV_SHUTDOWN_MSG].channel->OnChannelCallback =
+		&shutdown_onchannelcallback;
+	hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback;
+
+	return 0;
+}
+
+static void exit_hyperv_utils(void)
+{
+	printk(KERN_INFO "De-Registered HyperV Utility Driver\n");
+
+	hv_cb_utils[HV_SHUTDOWN_MSG].channel->OnChannelCallback =
+		&chn_cb_negotiate;
+	hv_cb_utils[HV_SHUTDOWN_MSG].callback = &chn_cb_negotiate;
+}
+
+module_init(init_hyperv_utils);
+module_exit(exit_hyperv_utils);
+
+MODULE_DESCRIPTION("Hyper-V Utilities");
+MODULE_VERSION(HV_DRV_VERSION);
+MODULE_LICENSE("GPL");