[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/drivers/hv/hv_snapshot.c b/src/kernel/linux/v4.14/drivers/hv/hv_snapshot.c
new file mode 100644
index 0000000..6831efd
--- /dev/null
+++ b/src/kernel/linux/v4.14/drivers/hv/hv_snapshot.c
@@ -0,0 +1,398 @@
+/*
+ * An implementation of host initiated guest snapshot.
+ *
+ *
+ * Copyright (C) 2013, Microsoft, Inc.
+ * Author : K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/net.h>
+#include <linux/nls.h>
+#include <linux/connector.h>
+#include <linux/workqueue.h>
+#include <linux/hyperv.h>
+
+#include "hyperv_vmbus.h"
+#include "hv_utils_transport.h"
+
+#define VSS_MAJOR 5
+#define VSS_MINOR 0
+#define VSS_VERSION (VSS_MAJOR << 16 | VSS_MINOR)
+
+#define VSS_VER_COUNT 1
+static const int vss_versions[] = {
+ VSS_VERSION
+};
+
+#define FW_VER_COUNT 1
+static const int fw_versions[] = {
+ UTIL_FW_VERSION
+};
+
+/*
+ * Timeout values are based on expecations from host
+ */
+#define VSS_FREEZE_TIMEOUT (15 * 60)
+
+/*
+ * Global state maintained for transaction that is being processed. For a class
+ * of integration services, including the "VSS service", the specified protocol
+ * is a "request/response" protocol which means that there can only be single
+ * outstanding transaction from the host at any given point in time. We use
+ * this to simplify memory management in this driver - we cache and process
+ * only one message at a time.
+ *
+ * While the request/response protocol is guaranteed by the host, we further
+ * ensure this by serializing packet processing in this driver - we do not
+ * read additional packets from the VMBUs until the current packet is fully
+ * handled.
+ */
+
+static struct {
+ int state; /* hvutil_device_state */
+ int recv_len; /* number of bytes received. */
+ struct vmbus_channel *recv_channel; /* chn we got the request */
+ u64 recv_req_id; /* request ID. */
+ struct hv_vss_msg *msg; /* current message */
+} vss_transaction;
+
+
+static void vss_respond_to_host(int error);
+
+/*
+ * This state maintains the version number registered by the daemon.
+ */
+static int dm_reg_value;
+
+static const char vss_devname[] = "vmbus/hv_vss";
+static __u8 *recv_buffer;
+static struct hvutil_transport *hvt;
+
+static void vss_timeout_func(struct work_struct *dummy);
+static void vss_handle_request(struct work_struct *dummy);
+
+static DECLARE_DELAYED_WORK(vss_timeout_work, vss_timeout_func);
+static DECLARE_WORK(vss_handle_request_work, vss_handle_request);
+
+static void vss_poll_wrapper(void *channel)
+{
+ /* Transaction is finished, reset the state here to avoid races. */
+ vss_transaction.state = HVUTIL_READY;
+ hv_vss_onchannelcallback(channel);
+}
+
+/*
+ * Callback when data is received from user mode.
+ */
+
+static void vss_timeout_func(struct work_struct *dummy)
+{
+ /*
+ * Timeout waiting for userspace component to reply happened.
+ */
+ pr_warn("VSS: timeout waiting for daemon to reply\n");
+ vss_respond_to_host(HV_E_FAIL);
+
+ hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper);
+}
+
+static void vss_register_done(void)
+{
+ hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper);
+ pr_debug("VSS: userspace daemon registered\n");
+}
+
+static int vss_handle_handshake(struct hv_vss_msg *vss_msg)
+{
+ u32 our_ver = VSS_OP_REGISTER1;
+
+ switch (vss_msg->vss_hdr.operation) {
+ case VSS_OP_REGISTER:
+ /* Daemon doesn't expect us to reply */
+ dm_reg_value = VSS_OP_REGISTER;
+ break;
+ case VSS_OP_REGISTER1:
+ /* Daemon expects us to reply with our own version */
+ if (hvutil_transport_send(hvt, &our_ver, sizeof(our_ver),
+ vss_register_done))
+ return -EFAULT;
+ dm_reg_value = VSS_OP_REGISTER1;
+ break;
+ default:
+ return -EINVAL;
+ }
+ pr_info("VSS: userspace daemon ver. %d connected\n", dm_reg_value);
+ return 0;
+}
+
+static int vss_on_msg(void *msg, int len)
+{
+ struct hv_vss_msg *vss_msg = (struct hv_vss_msg *)msg;
+
+ if (len != sizeof(*vss_msg)) {
+ pr_debug("VSS: Message size does not match length\n");
+ return -EINVAL;
+ }
+
+ if (vss_msg->vss_hdr.operation == VSS_OP_REGISTER ||
+ vss_msg->vss_hdr.operation == VSS_OP_REGISTER1) {
+ /*
+ * Don't process registration messages if we're in the middle
+ * of a transaction processing.
+ */
+ if (vss_transaction.state > HVUTIL_READY) {
+ pr_debug("VSS: Got unexpected registration request\n");
+ return -EINVAL;
+ }
+
+ return vss_handle_handshake(vss_msg);
+ } else if (vss_transaction.state == HVUTIL_USERSPACE_REQ) {
+ vss_transaction.state = HVUTIL_USERSPACE_RECV;
+
+ if (vss_msg->vss_hdr.operation == VSS_OP_HOT_BACKUP)
+ vss_transaction.msg->vss_cf.flags =
+ VSS_HBU_NO_AUTO_RECOVERY;
+
+ if (cancel_delayed_work_sync(&vss_timeout_work)) {
+ vss_respond_to_host(vss_msg->error);
+ /* Transaction is finished, reset the state. */
+ hv_poll_channel(vss_transaction.recv_channel,
+ vss_poll_wrapper);
+ }
+ } else {
+ /* This is a spurious call! */
+ pr_debug("VSS: Transaction not active\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void vss_send_op(void)
+{
+ int op = vss_transaction.msg->vss_hdr.operation;
+ int rc;
+ struct hv_vss_msg *vss_msg;
+
+ /* The transaction state is wrong. */
+ if (vss_transaction.state != HVUTIL_HOSTMSG_RECEIVED) {
+ pr_debug("VSS: Unexpected attempt to send to daemon\n");
+ return;
+ }
+
+ vss_msg = kzalloc(sizeof(*vss_msg), GFP_KERNEL);
+ if (!vss_msg)
+ return;
+
+ vss_msg->vss_hdr.operation = op;
+
+ vss_transaction.state = HVUTIL_USERSPACE_REQ;
+
+ schedule_delayed_work(&vss_timeout_work, op == VSS_OP_FREEZE ?
+ VSS_FREEZE_TIMEOUT * HZ : HV_UTIL_TIMEOUT * HZ);
+
+ rc = hvutil_transport_send(hvt, vss_msg, sizeof(*vss_msg), NULL);
+ if (rc) {
+ pr_warn("VSS: failed to communicate to the daemon: %d\n", rc);
+ if (cancel_delayed_work_sync(&vss_timeout_work)) {
+ vss_respond_to_host(HV_E_FAIL);
+ vss_transaction.state = HVUTIL_READY;
+ }
+ }
+
+ kfree(vss_msg);
+}
+
+static void vss_handle_request(struct work_struct *dummy)
+{
+ switch (vss_transaction.msg->vss_hdr.operation) {
+ /*
+ * Initiate a "freeze/thaw" operation in the guest.
+ * We respond to the host once the operation is complete.
+ *
+ * We send the message to the user space daemon and the operation is
+ * performed in the daemon.
+ */
+ case VSS_OP_THAW:
+ case VSS_OP_FREEZE:
+ case VSS_OP_HOT_BACKUP:
+ if (vss_transaction.state < HVUTIL_READY) {
+ /* Userspace is not registered yet */
+ pr_debug("VSS: Not ready for request.\n");
+ vss_respond_to_host(HV_E_FAIL);
+ return;
+ }
+
+ pr_debug("VSS: Received request for op code: %d\n",
+ vss_transaction.msg->vss_hdr.operation);
+ vss_transaction.state = HVUTIL_HOSTMSG_RECEIVED;
+ vss_send_op();
+ return;
+ case VSS_OP_GET_DM_INFO:
+ vss_transaction.msg->dm_info.flags = 0;
+ break;
+ default:
+ break;
+ }
+
+ vss_respond_to_host(0);
+ hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper);
+}
+
+/*
+ * Send a response back to the host.
+ */
+
+static void
+vss_respond_to_host(int error)
+{
+ struct icmsg_hdr *icmsghdrp;
+ u32 buf_len;
+ struct vmbus_channel *channel;
+ u64 req_id;
+
+ /*
+ * Copy the global state for completing the transaction. Note that
+ * only one transaction can be active at a time.
+ */
+
+ buf_len = vss_transaction.recv_len;
+ channel = vss_transaction.recv_channel;
+ req_id = vss_transaction.recv_req_id;
+
+ icmsghdrp = (struct icmsg_hdr *)
+ &recv_buffer[sizeof(struct vmbuspipe_hdr)];
+
+ if (channel->onchannel_callback == NULL)
+ /*
+ * We have raced with util driver being unloaded;
+ * silently return.
+ */
+ return;
+
+ icmsghdrp->status = error;
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
+ VM_PKT_DATA_INBAND, 0);
+
+}
+
+/*
+ * This callback is invoked when we get a VSS message from the host.
+ * The host ensures that only one VSS transaction can be active at a time.
+ */
+
+void hv_vss_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+ struct hv_vss_msg *vss_msg;
+ int vss_srv_version;
+
+ struct icmsg_hdr *icmsghdrp;
+
+ if (vss_transaction.state > HVUTIL_READY)
+ return;
+
+ vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+ &requestid);
+
+ if (recvlen > 0) {
+ icmsghdrp = (struct icmsg_hdr *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr)];
+
+ if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ if (vmbus_prep_negotiate_resp(icmsghdrp,
+ recv_buffer, fw_versions, FW_VER_COUNT,
+ vss_versions, VSS_VER_COUNT,
+ NULL, &vss_srv_version)) {
+
+ pr_info("VSS IC version %d.%d\n",
+ vss_srv_version >> 16,
+ vss_srv_version & 0xFFFF);
+ }
+ } else {
+ vss_msg = (struct hv_vss_msg *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ /*
+ * Stash away this global state for completing the
+ * transaction; note transactions are serialized.
+ */
+
+ vss_transaction.recv_len = recvlen;
+ vss_transaction.recv_req_id = requestid;
+ vss_transaction.msg = (struct hv_vss_msg *)vss_msg;
+
+ schedule_work(&vss_handle_request_work);
+ return;
+ }
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+ | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, recv_buffer,
+ recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+ }
+
+}
+
+static void vss_on_reset(void)
+{
+ if (cancel_delayed_work_sync(&vss_timeout_work))
+ vss_respond_to_host(HV_E_FAIL);
+ vss_transaction.state = HVUTIL_DEVICE_INIT;
+}
+
+int
+hv_vss_init(struct hv_util_service *srv)
+{
+ if (vmbus_proto_version < VERSION_WIN8_1) {
+ pr_warn("Integration service 'Backup (volume snapshot)'"
+ " not supported on this host version.\n");
+ return -ENOTSUPP;
+ }
+ recv_buffer = srv->recv_buffer;
+ vss_transaction.recv_channel = srv->channel;
+
+ /*
+ * When this driver loads, the user level daemon that
+ * processes the host requests may not yet be running.
+ * Defer processing channel callbacks until the daemon
+ * has registered.
+ */
+ vss_transaction.state = HVUTIL_DEVICE_INIT;
+
+ hvt = hvutil_transport_init(vss_devname, CN_VSS_IDX, CN_VSS_VAL,
+ vss_on_msg, vss_on_reset);
+ if (!hvt) {
+ pr_warn("VSS: Failed to initialize transport\n");
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+void hv_vss_deinit(void)
+{
+ vss_transaction.state = HVUTIL_DEVICE_DYING;
+ cancel_delayed_work_sync(&vss_timeout_work);
+ cancel_work_sync(&vss_handle_request_work);
+ hvutil_transport_destroy(hvt);
+}