static int kvp_handle_handshake(struct hv_kvp_msg *msg)
{
int ret = 1;
switch (msg->kvp_hdr.operation) {
case KVP_OP_REGISTER:
dm_reg_value = KVP_OP_REGISTER;
pr_info("KVP: IP injection functionality not available\n");
pr_info("KVP: Upgrade the KVP daemon\n");
break;
case KVP_OP_REGISTER1:
dm_reg_value = KVP_OP_REGISTER1;
break;
default:
pr_info("KVP: incompatible daemon\n");
pr_info("KVP: KVP version: %d, Daemon version: %d\n",
KVP_OP_REGISTER1, msg->kvp_hdr.operation);
ret = 0;
}
if (ret) {
/*
* We have a compatible daemon; complete the handshake.
*/
pr_info("KVP: user-mode registering done.\n");
kvp_register(dm_reg_value);
kvp_transaction.active = false;
if (kvp_transaction.kvp_context)
poll_channel(kvp_transaction.kvp_context);
}
return ret;
}
/**
* \brief Return next event on given waitset, if one is already pending
*
* This is essentially a non-blocking variant of get_next_event(). It should be
* used with great care, to avoid the creation of busy-waiting loops.
*
* \param ws Waitset
* \param retclosure Pointer to storage space for returned event closure
*
* \returns LIB_ERR_NO_EVENT if nothing is pending
*/
errval_t check_for_event(struct waitset *ws, struct event_closure *retclosure)
{
struct waitset_chanstate *chan;
int pollcount = 0;
assert(ws != NULL);
assert(retclosure != NULL);
recheck: ;
// are there any pending events on the waitset?
dispatcher_handle_t handle = disp_disable();
chan = get_pending_event_disabled(ws);
disp_enable(handle);
if (chan != NULL) {
*retclosure = chan->closure;
return SYS_ERR_OK;
}
// if there are no pending events, poll all channels once
if (ws->polled != NULL && pollcount++ == 0) {
for (chan = ws->polled;
chan != NULL && chan->waitset == ws && chan->state == CHAN_POLLED;
chan = chan->next) {
poll_channel(chan);
if (ws->pending != NULL) {
goto recheck;
}
if (chan->next == ws->polled) { // reached the start of the queue
break;
}
}
}
return LIB_ERR_NO_EVENT;
}
static void
kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
{
struct hv_kvp_msg *kvp_msg;
struct hv_kvp_exchg_msg_value *kvp_data;
char *key_name;
char *value;
struct icmsg_hdr *icmsghdrp;
int keylen = 0;
int valuelen = 0;
u32 buf_len;
struct vmbus_channel *channel;
u64 req_id;
int ret;
/*
* If a transaction is not active; log and return.
*/
if (!kvp_transaction.active) {
/*
* This is a spurious call!
*/
pr_warn("KVP: Transaction not active\n");
return;
}
/*
* Copy the global state for completing the transaction. Note that
* only one transaction can be active at a time.
*/
buf_len = kvp_transaction.recv_len;
channel = kvp_transaction.recv_channel;
req_id = kvp_transaction.recv_req_id;
kvp_transaction.active = false;
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;
/*
* If the error parameter is set, terminate the host's enumeration
* on this pool.
*/
if (error) {
/*
* Something failed or we have timedout;
* terminate the current host-side iteration.
*/
goto response_done;
}
kvp_msg = (struct hv_kvp_msg *)
&recv_buffer[sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
switch (kvp_transaction.kvp_msg->kvp_hdr.operation) {
case KVP_OP_GET_IP_INFO:
ret = process_ob_ipinfo(msg_to_host,
(struct hv_kvp_ip_msg *)kvp_msg,
KVP_OP_GET_IP_INFO);
if (ret < 0)
icmsghdrp->status = HV_E_FAIL;
goto response_done;
case KVP_OP_SET_IP_INFO:
goto response_done;
case KVP_OP_GET:
kvp_data = &kvp_msg->body.kvp_get.data;
goto copy_value;
case KVP_OP_SET:
case KVP_OP_DELETE:
goto response_done;
default:
break;
}
kvp_data = &kvp_msg->body.kvp_enum_data.data;
key_name = msg_to_host->body.kvp_enum_data.data.key;
/*
* The windows host expects the key/value pair to be encoded
* in utf16. Ensure that the key/value size reported to the host
* will be less than or equal to the MAX size (including the
* terminating character).
*/
keylen = utf8s_to_utf16s(key_name, strlen(key_name), UTF16_HOST_ENDIAN,
(wchar_t *) kvp_data->key,
(HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2);
kvp_data->key_size = 2*(keylen + 1); /* utf16 encoding */
copy_value:
value = msg_to_host->body.kvp_enum_data.data.value;
valuelen = utf8s_to_utf16s(value, strlen(value), UTF16_HOST_ENDIAN,
(wchar_t *) kvp_data->value,
(HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2);
kvp_data->value_size = 2*(valuelen + 1); /* utf16 encoding */
/*
* If the utf8s to utf16s conversion failed; notify host
* of the error.
*/
if ((keylen < 0) || (valuelen < 0))
icmsghdrp->status = HV_E_FAIL;
kvp_data->value_type = REG_SZ; /* all our values are strings */
response_done:
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
VM_PKT_DATA_INBAND, 0);
poll_channel(channel);
}
static errval_t get_next_event_debug(struct waitset *ws,
struct event_closure *retclosure, bool debug)
{
struct waitset_chanstate *chan;
bool was_polling = false;
cycles_t pollcycles;
assert(ws != NULL);
assert(retclosure != NULL);
// unconditionally disable ourselves and check for events
// if we decide we have to start polling, we'll jump back up here
goto check_for_events;
/* ------------ POLLING LOOP; RUNS WHILE ENABLED ------------ */
polling_loop:
was_polling = true;
assert(ws->polling); // this thread is polling
// get the amount of cycles we want to poll for
pollcycles = pollcycles_reset();
// while there are no pending events, poll channels
while (ws->polled != NULL && ws->pending == NULL) {
struct waitset_chanstate *nextchan = NULL;
// NB: Polling policy is to return as soon as a pending event
// appears, not bother looking at the rest of the polling queue
for (chan = ws->polled;
chan != NULL && chan->waitset == ws && chan->state == CHAN_POLLED
&& ws->pending == NULL;
chan = nextchan) {
nextchan = chan->next;
poll_channel(chan);
// update pollcycles
pollcycles = pollcycles_update(pollcycles);
// yield the thread if we exceed the cycle count limit
if (ws->pending == NULL && pollcycles_expired(pollcycles)) {
if (debug) {
if (strcmp(disp_name(), "netd") != 0) {
// Print the callback trace so that we know which call is leading
// the schedule removal and
printf("%s: callstack: %p %p %p %p\n", disp_name(),
__builtin_return_address(0),
__builtin_return_address(1),
__builtin_return_address(2),
__builtin_return_address(3));
}
}
thread_yield();
pollcycles = pollcycles_reset();
}
}
// ensure that we restart polling from the place we left off here,
// if the next channel is a valid one
if (nextchan != NULL && nextchan->waitset == ws
&& nextchan->state == CHAN_POLLED) {
ws->polled = nextchan;
}
}
/* ------------ STATE MACHINERY; RUNS WHILE DISABLED ------------ */
check_for_events: ;
dispatcher_handle_t handle = disp_disable();
// are there any pending events on the waitset?
chan = get_pending_event_disabled(ws);
if (chan != NULL) {
// if we need to poll, and we have a blocked thread, wake it up to do so
if (was_polling && ws->polled != NULL && ws->waiting_threads != NULL) {
// start a blocked thread polling
struct thread *t;
t = thread_unblock_one_disabled(handle, &ws->waiting_threads, NULL);
assert_disabled(t == NULL); // shouldn't see a remote thread
} else if (was_polling) {
// I'm stopping polling, and there is nobody else
assert_disabled(ws->polling);
ws->polling = false;
}
disp_enable(handle);
*retclosure = chan->closure;
return SYS_ERR_OK;
}
// If we got here and there are channels to poll but no-one is polling,
// then either we never polled, or we lost a race on the channel we picked.
// Either way, we'd better start polling again.
if (ws->polled != NULL && (was_polling || !ws->polling)) {
if (!was_polling) {
ws->polling = true;
}
disp_enable(handle);
goto polling_loop;
}
// otherwise block awaiting an event
chan = thread_block_disabled(handle, &ws->waiting_threads);
if (chan == NULL) {
// not a real event, just a wakeup to get us to start polling!
assert(ws->polling);
goto polling_loop;
} else {
*retclosure = chan->closure;
return SYS_ERR_OK;
}
}