clk: rockchip: support setting ddr clock via SCPI APIs
[firefly-linux-kernel-4.4.55.git] / drivers / hv / hv_kvp.c
index ed50e9e83c61a8ec8690c757876a0300096f59d4..ce4d3a9354916225079f5b12dbf179c6835ffa56 100644 (file)
 #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 WS2008_SRV_MAJOR       1
+#define WS2008_SRV_MINOR       0
+#define WS2008_SRV_VERSION     (WS2008_SRV_MAJOR << 16 | WS2008_SRV_MINOR)
+
+#define WIN7_SRV_MAJOR   3
+#define WIN7_SRV_MINOR   0
+#define WIN7_SRV_VERSION     (WIN7_SRV_MAJOR << 16 | WIN7_SRV_MINOR)
+
+#define WIN8_SRV_MAJOR   4
+#define WIN8_SRV_MINOR   0
+#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 */
        u64 recv_req_id; /* request ID. */
-       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.
  */
@@ -64,57 +77,62 @@ static void kvp_send_key(struct work_struct *dummy);
 
 
 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;
+static struct completion release_event;
 /*
  * Register the kernel component with the user-level daemon.
  * As part of this registration, pass the LIC version number.
+ * This number has no meaning, it satisfies the registration protocol.
  */
+#define HV_DRV_VERSION           "3.1"
+
+static void kvp_poll_wrapper(void *channel)
+{
+       /* Transaction is finished, reset the state here to avoid races. */
+       kvp_transaction.state = HVUTIL_READY;
+       hv_kvp_onchannelcallback(channel);
+}
 
 static void
 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, 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);
+
+       hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
 }
 
 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;
@@ -128,20 +146,18 @@ static int kvp_handle_handshake(struct hv_kvp_msg *msg)
                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)
-                       hv_kvp_onchannelcallback(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;
 }
 
 
@@ -149,26 +165,30 @@ static int kvp_handle_handshake(struct hv_kvp_msg *msg)
  * 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.
@@ -198,8 +218,12 @@ kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
         * 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);
+               hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
+       }
+
+       return 0;
 }
 
 
@@ -316,22 +340,22 @@ static void process_ib_ipinfo(void *in_msg, void *out_msg, int op)
 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;
        __u8 pool = kvp_transaction.kvp_msg->kvp_hdr.pool;
        __u32 val32;
        __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;
@@ -418,9 +442,17 @@ kvp_send_key(struct work_struct *dummy)
                        break;
        }
 
-       msg->len = sizeof(struct hv_kvp_msg);
-       cn_netlink_send(msg, 0, GFP_ATOMIC);
-       kfree(msg);
+       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_timeout_work)) {
+                       kvp_respond_to_host(message, HV_E_FAIL);
+                       kvp_transaction.state = HVUTIL_READY;
+               }
+       }
+
+       kfree(message);
 
        return;
 }
@@ -444,17 +476,6 @@ kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
        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.
@@ -464,8 +485,6 @@ kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
        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)];
 
@@ -552,7 +571,6 @@ response_done:
 
        vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
                                VM_PKT_DATA_INBAND, 0);
-
 }
 
 /*
@@ -575,17 +593,13 @@ void hv_kvp_onchannelcallback(void *context)
 
        struct icmsg_hdr *icmsghdrp;
        struct icmsg_negotiate *negop = NULL;
+       int util_fw_version;
+       int kvp_srv_version;
 
-       if (kvp_transaction.active) {
-               /*
-                * We will defer processing this callback once
-                * the current transaction is complete.
-                */
-               kvp_transaction.kvp_context = context;
+       if (kvp_transaction.state > HVUTIL_READY)
                return;
-       }
 
-       vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+       vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen,
                         &requestid);
 
        if (recvlen > 0) {
@@ -593,8 +607,28 @@ void hv_kvp_onchannelcallback(void *context)
                        sizeof(struct vmbuspipe_hdr)];
 
                if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+                       /*
+                        * Based on the host, select appropriate
+                        * framework and service versions we will
+                        * negotiate.
+                        */
+                       switch (vmbus_proto_version) {
+                       case (VERSION_WS2008):
+                               util_fw_version = UTIL_WS2K8_FW_VERSION;
+                               kvp_srv_version = WS2008_SRV_VERSION;
+                               break;
+                       case (VERSION_WIN7):
+                               util_fw_version = UTIL_FW_VERSION;
+                               kvp_srv_version = WIN7_SRV_VERSION;
+                               break;
+                       default:
+                               util_fw_version = UTIL_FW_VERSION;
+                               kvp_srv_version = WIN8_SRV_VERSION;
+                       }
                        vmbus_prep_negotiate_resp(icmsghdrp, negop,
-                                recv_buffer, MAX_SRV_VER, MAX_SRV_VER);
+                                recv_buffer, util_fw_version,
+                                kvp_srv_version);
+
                } else {
                        kvp_msg = (struct hv_kvp_msg *)&recv_buffer[
                                sizeof(struct vmbuspipe_hdr) +
@@ -608,9 +642,15 @@ void hv_kvp_onchannelcallback(void *context)
                        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.
@@ -621,7 +661,8 @@ void hv_kvp_onchannelcallback(void *context)
                         * user-mode not responding.
                         */
                        schedule_work(&kvp_sendkey_work);
-                       schedule_delayed_work(&kvp_work, 5*HZ);
+                       schedule_delayed_work(&kvp_timeout_work,
+                                             HV_UTIL_TIMEOUT * HZ);
 
                        return;
 
@@ -637,30 +678,41 @@ void hv_kvp_onchannelcallback(void *context)
 
 }
 
+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;
+       complete(&release_event);
+}
+
 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;
 
+       init_completion(&release_event);
        /*
         * 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.
         */
-       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);
+       wait_for_completion(&release_event);
 }