#include <linux/workqueue.h>
#include <linux/hyperv.h>
+#include "hyperv_vmbus.h"
+#include "hv_utils_transport.h"
/*
* Pre win8 version numbers used in ws2008 and ws 2008 r2 (win7)
#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
/*
- * Global state maintained for transaction that is being processed.
- * Note that only one transaction can be active at any point in time.
+ * Global state maintained for transaction that is being processed. For a class
+ * of integration services, including the "KVP 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.
*
- * This state is set when we receive a request from the host; we
- * cleanup this state when the transaction is completed - when we respond
- * to the host with the key value.
+ * 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 {
- bool active; /* transaction status - active or not */
+ int state; /* hvutil_device_state */
int recv_len; /* number of bytes received. */
struct hv_kvp_msg *kvp_msg; /* current message */
struct vmbus_channel *recv_channel; /* chn we got the request */
void *kvp_context; /* for the channel callback */
} kvp_transaction;
-/*
- * Before we can accept KVP messages from the host, we need
- * to handshake with the user level daemon. This state tracks
- * if we are in the handshake phase.
- */
-static bool in_hand_shake = true;
-
/*
* This state maintains the version number registered by the daemon.
*/
static void kvp_respond_to_host(struct hv_kvp_msg *msg, int error);
-static void kvp_work_func(struct work_struct *dummy);
+static void kvp_timeout_func(struct work_struct *dummy);
static void kvp_register(int);
-static DECLARE_DELAYED_WORK(kvp_work, kvp_work_func);
+static DECLARE_DELAYED_WORK(kvp_timeout_work, kvp_timeout_func);
static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
-static struct cb_id kvp_id = { CN_KVP_IDX, CN_KVP_VAL };
-static const char kvp_name[] = "kvp_kernel_module";
+static const char kvp_devname[] = "vmbus/hv_kvp";
static u8 *recv_buffer;
+static struct hvutil_transport *hvt;
/*
* Register the kernel component with the user-level daemon.
* As part of this registration, pass the LIC version number.
kvp_register(int reg_value)
{
- struct cn_msg *msg;
struct hv_kvp_msg *kvp_msg;
char *version;
- msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg), GFP_ATOMIC);
+ kvp_msg = kzalloc(sizeof(*kvp_msg), GFP_KERNEL);
- if (msg) {
- kvp_msg = (struct hv_kvp_msg *)msg->data;
+ if (kvp_msg) {
version = kvp_msg->body.kvp_register.version;
- msg->id.idx = CN_KVP_IDX;
- msg->id.val = CN_KVP_VAL;
-
kvp_msg->kvp_hdr.operation = reg_value;
strcpy(version, HV_DRV_VERSION);
- msg->len = sizeof(struct hv_kvp_msg);
- cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
- kfree(msg);
+
+ hvutil_transport_send(hvt, kvp_msg, sizeof(*kvp_msg));
+ kfree(kvp_msg);
}
}
-static void
-kvp_work_func(struct work_struct *dummy)
+
+static void kvp_timeout_func(struct work_struct *dummy)
{
/*
* If the timer fires, the user-mode component has not responded;
* process the pending transaction.
*/
kvp_respond_to_host(NULL, HV_E_FAIL);
-}
-static void poll_channel(struct vmbus_channel *channel)
-{
- if (channel->target_cpu != smp_processor_id())
- smp_call_function_single(channel->target_cpu,
- hv_kvp_onchannelcallback,
- channel, true);
- else
- hv_kvp_onchannelcallback(channel);
-}
+ /* Transaction is finished, reset the state. */
+ if (kvp_transaction.state > HVUTIL_READY)
+ kvp_transaction.state = HVUTIL_READY;
+ hv_poll_channel(kvp_transaction.kvp_context,
+ hv_kvp_onchannelcallback);
+}
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: incompatible daemon\n");
pr_info("KVP: KVP version: %d, Daemon version: %d\n",
KVP_OP_REGISTER1, msg->kvp_hdr.operation);
- ret = 0;
+ return -EINVAL;
}
- 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;
+ /*
+ * We have a compatible daemon; complete the handshake.
+ */
+ pr_debug("KVP: userspace daemon ver. %d registered\n",
+ KVP_OP_REGISTER);
+ kvp_register(dm_reg_value);
+ kvp_transaction.state = HVUTIL_READY;
+
+ return 0;
}
* Callback when data is received from user mode.
*/
-static void
-kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
+static int kvp_on_msg(void *msg, int len)
{
- struct hv_kvp_msg *message;
+ struct hv_kvp_msg *message = (struct hv_kvp_msg *)msg;
struct hv_kvp_msg_enumerate *data;
int error = 0;
- message = (struct hv_kvp_msg *)msg->data;
+ if (len < sizeof(*message))
+ return -EINVAL;
/*
* If we are negotiating the version information
* with the daemon; handle that first.
*/
- if (in_hand_shake) {
- if (kvp_handle_handshake(message))
- in_hand_shake = false;
- return;
+ if (kvp_transaction.state < HVUTIL_READY) {
+ return kvp_handle_handshake(message);
}
+ /* We didn't send anything to userspace so the reply is spurious */
+ if (kvp_transaction.state < HVUTIL_USERSPACE_REQ)
+ return -EINVAL;
+
+ kvp_transaction.state = HVUTIL_USERSPACE_RECV;
+
/*
* Based on the version of the daemon, we propagate errors from the
* daemon differently.
* Complete the transaction by forwarding the key value
* to the host. But first, cancel the timeout.
*/
- if (cancel_delayed_work_sync(&kvp_work))
+ if (cancel_delayed_work_sync(&kvp_timeout_work)) {
kvp_respond_to_host(message, error);
+ kvp_transaction.state = HVUTIL_READY;
+ hv_poll_channel(kvp_transaction.kvp_context,
+ hv_kvp_onchannelcallback);
+ }
+
+ return 0;
}
static void
kvp_send_key(struct work_struct *dummy)
{
- struct cn_msg *msg;
struct hv_kvp_msg *message;
struct hv_kvp_msg *in_msg;
__u8 operation = kvp_transaction.kvp_msg->kvp_hdr.operation;
__u64 val64;
int rc;
- msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg) , GFP_ATOMIC);
- if (!msg)
+ /* The transaction state is wrong. */
+ if (kvp_transaction.state != HVUTIL_HOSTMSG_RECEIVED)
return;
- msg->id.idx = CN_KVP_IDX;
- msg->id.val = CN_KVP_VAL;
+ message = kzalloc(sizeof(*message), GFP_KERNEL);
+ if (!message)
+ return;
- message = (struct hv_kvp_msg *)msg->data;
message->kvp_hdr.operation = operation;
message->kvp_hdr.pool = pool;
in_msg = kvp_transaction.kvp_msg;
break;
}
- msg->len = sizeof(struct hv_kvp_msg);
- rc = cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
+ kvp_transaction.state = HVUTIL_USERSPACE_REQ;
+ rc = hvutil_transport_send(hvt, message, sizeof(*message));
if (rc) {
pr_debug("KVP: failed to communicate to the daemon: %d\n", rc);
- if (cancel_delayed_work_sync(&kvp_work))
+ if (cancel_delayed_work_sync(&kvp_timeout_work)) {
kvp_respond_to_host(message, HV_E_FAIL);
+ kvp_transaction.state = HVUTIL_READY;
+ }
}
- kfree(msg);
+ kfree(message);
return;
}
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.
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)];
vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
VM_PKT_DATA_INBAND, 0);
- poll_channel(channel);
}
/*
int util_fw_version;
int kvp_srv_version;
- if (kvp_transaction.active) {
+ if (kvp_transaction.state > HVUTIL_READY) {
/*
* We will defer processing this callback once
* the current transaction is complete.
kvp_transaction.kvp_context = context;
return;
}
+ kvp_transaction.kvp_context = NULL;
vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen,
&requestid);
kvp_transaction.recv_len = recvlen;
kvp_transaction.recv_channel = channel;
kvp_transaction.recv_req_id = requestid;
- kvp_transaction.active = true;
kvp_transaction.kvp_msg = kvp_msg;
+ if (kvp_transaction.state < HVUTIL_READY) {
+ /* Userspace is not registered yet */
+ kvp_respond_to_host(NULL, HV_E_FAIL);
+ return;
+ }
+ kvp_transaction.state = HVUTIL_HOSTMSG_RECEIVED;
+
/*
* Get the information from the
* user-mode component.
* user-mode not responding.
*/
schedule_work(&kvp_sendkey_work);
- schedule_delayed_work(&kvp_work, 5*HZ);
+ schedule_delayed_work(&kvp_timeout_work, 5*HZ);
return;
}
+static void kvp_on_reset(void)
+{
+ if (cancel_delayed_work_sync(&kvp_timeout_work))
+ kvp_respond_to_host(NULL, HV_E_FAIL);
+ kvp_transaction.state = HVUTIL_DEVICE_INIT;
+}
+
int
hv_kvp_init(struct hv_util_service *srv)
{
- int err;
-
- err = cn_add_callback(&kvp_id, kvp_name, kvp_cn_callback);
- if (err)
- return err;
recv_buffer = srv->recv_buffer;
/*
* Defer processing channel callbacks until the daemon
* has registered.
*/
- kvp_transaction.active = true;
+ kvp_transaction.state = HVUTIL_DEVICE_INIT;
+
+ hvt = hvutil_transport_init(kvp_devname, CN_KVP_IDX, CN_KVP_VAL,
+ kvp_on_msg, kvp_on_reset);
+ if (!hvt)
+ return -EFAULT;
return 0;
}
void hv_kvp_deinit(void)
{
- cn_del_callback(&kvp_id);
- cancel_delayed_work_sync(&kvp_work);
+ kvp_transaction.state = HVUTIL_DEVICE_DYING;
+ cancel_delayed_work_sync(&kvp_timeout_work);
cancel_work_sync(&kvp_sendkey_work);
+ hvutil_transport_destroy(hvt);
}
Code Review / kvmfornfv.git / blobdiff