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);
}
static void vss_send_op(struct work_struct *dummy)
{
int op = vss_transaction.msg->vss_hdr.operation;
int rc;
struct cn_msg *msg;
struct hv_vss_msg *vss_msg;
msg = kzalloc(sizeof(*msg) + sizeof(*vss_msg), GFP_ATOMIC);
if (!msg)
return;
vss_msg = (struct hv_vss_msg *)msg->data;
msg->id.idx = CN_VSS_IDX;
msg->id.val = CN_VSS_VAL;
vss_msg->vss_hdr.operation = op;
msg->len = sizeof(struct hv_vss_msg);
rc = cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
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);
}
kfree(msg);
return;
}
static void vss_send_op(struct work_struct *dummy)
{
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)
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;
rc = hvutil_transport_send(hvt, vss_msg, sizeof(*vss_msg));
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);
return;
}
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))
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)
return -EINVAL;
return vss_handle_handshake(vss_msg);
} else if (vss_transaction.state == HVUTIL_USERSPACE_REQ) {
vss_transaction.state = HVUTIL_USERSPACE_RECV;
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_warn("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_on_reset(void)
{
if (cancel_delayed_work_sync(&vss_timeout_work))
vss_respond_to_host(HV_E_FAIL);
vss_transaction.state = HVUTIL_DEVICE_INIT;
complete(&release_event);
}
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);
}
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_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);
/* Transaction is finished, reset the state. */
if (vss_transaction.state > HVUTIL_READY)
vss_transaction.state = HVUTIL_READY;
hv_poll_channel(vss_transaction.vss_context,
hv_vss_onchannelcallback);
}
static void
vss_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
struct hv_vss_msg *vss_msg;
vss_msg = (struct hv_vss_msg *)msg->data;
if (vss_msg->vss_hdr.operation == VSS_OP_REGISTER) {
pr_info("VSS daemon registered\n");
vss_transaction.active = false;
if (vss_transaction.recv_channel != NULL)
hv_vss_onchannelcallback(vss_transaction.recv_channel);
return;
}
vss_respond_to_host(vss_msg->error);
}
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;
}
void hv_vss_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
u32 recvlen;
u64 requestid;
struct hv_vss_msg *vss_msg;
struct icmsg_hdr *icmsghdrp;
struct icmsg_negotiate *negop = NULL;
if (vss_transaction.active) {
/*
* We will defer processing this callback once
* the current transaction is complete.
*/
vss_transaction.recv_channel = channel;
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) {
vmbus_prep_negotiate_resp(icmsghdrp, negop,
recv_buffer, UTIL_FW_VERSION,
VSS_VERSION);
} 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_channel = channel;
vss_transaction.recv_req_id = requestid;
vss_transaction.active = true;
vss_transaction.msg = (struct hv_vss_msg *)vss_msg;
switch (vss_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_FREEZE:
case VSS_OP_THAW:
schedule_work(&vss_send_op_work);
schedule_delayed_work(&vss_timeout_work,
VSS_USERSPACE_TIMEOUT);
return;
case VSS_OP_HOT_BACKUP:
vss_msg->vss_cf.flags =
VSS_HBU_NO_AUTO_RECOVERY;
vss_respond_to_host(0);
return;
case VSS_OP_GET_DM_INFO:
vss_msg->dm_info.flags = 0;
vss_respond_to_host(0);
return;
default:
vss_respond_to_host(0);
return;
}
}
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, recv_buffer,
recvlen, requestid,
VM_PKT_DATA_INBAND, 0);
}
}
