GUI: Fix Tomato RAF theme for all builds. Compilation typo.

[tomato.git] / release / src-rt-6.x.4708 / linux / linux-2.6.36 / drivers / staging / hv / channel_mgmt.c

/*
 * Copyright (c) 2009, Microsoft Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place - Suite 330, Boston, MA 02111-1307 USA.
 *
 * Authors:
 *   Haiyang Zhang <haiyangz@microsoft.com>
 *   Hank Janssen  <hjanssen@microsoft.com>
 */
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/completion.h>
#include "osd.h"
#include "logging.h"
#include "vmbus_private.h"
#include "utils.h"

struct vmbus_channel_message_table_entry {
        enum vmbus_channel_message_type messageType;
        void (*messageHandler)(struct vmbus_channel_message_header *msg);
};

#define MAX_MSG_TYPES                    3
#define MAX_NUM_DEVICE_CLASSES_SUPPORTED 7

static const struct hv_guid
        gSupportedDeviceClasses[MAX_NUM_DEVICE_CLASSES_SUPPORTED] = {
        /* {ba6163d9-04a1-4d29-b605-72e2ffb1dc7f} */
        /* Storage - SCSI */
        {
                .data  = {
                        0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
                        0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f
                }
        },

        /* {F8615163-DF3E-46c5-913F-F2D2F965ED0E} */
        /* Network */
        {
                .data = {
                        0x63, 0x51, 0x61, 0xF8, 0x3E, 0xDF, 0xc5, 0x46,
                        0x91, 0x3F, 0xF2, 0xD2, 0xF9, 0x65, 0xED, 0x0E
                }
        },

        /* {CFA8B69E-5B4A-4cc0-B98B-8BA1A1F3F95A} */
        /* Input */
        {
                .data = {
                        0x9E, 0xB6, 0xA8, 0xCF, 0x4A, 0x5B, 0xc0, 0x4c,
                        0xB9, 0x8B, 0x8B, 0xA1, 0xA1, 0xF3, 0xF9, 0x5A
                }
        },

        /* {32412632-86cb-44a2-9b5c-50d1417354f5} */
        /* IDE */
        {
                .data = {
                        0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
                        0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5
                }
        },
        /* 0E0B6031-5213-4934-818B-38D90CED39DB */
        /* Shutdown */
        {
                .data = {
                        0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
                        0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
                }
        },
        /* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
        /* TimeSync */
        {
                .data = {
                        0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
                        0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
                }
        },
        /* {57164f39-9115-4e78-ab55-382f3bd5422d} */
        /* Heartbeat */
        {
                .data = {
                        0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
                        0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
                }
        },
};


/**
 * prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
 * @icmsghdrp: Pointer to msg header structure
 * @icmsg_negotiate: Pointer to negotiate message structure
 * @buf: Raw buffer channel data
 *
 * @icmsghdrp is of type &struct icmsg_hdr.
 * @negop is of type &struct icmsg_negotiate.
 * Set up and fill in default negotiate response message. This response can
 * come from both the vmbus driver and the hv_utils driver. The current api
 * will respond properly to both Windows 2008 and Windows 2008-R2 operating
 * systems.
 *
 * Mainly used by Hyper-V drivers.
 */
void prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
                             struct icmsg_negotiate *negop,
                             u8 *buf)
{
        if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
                icmsghdrp->icmsgsize = 0x10;

                negop = (struct icmsg_negotiate *)&buf[
                        sizeof(struct vmbuspipe_hdr) +
                        sizeof(struct icmsg_hdr)];

                if (negop->icframe_vercnt == 2 &&
                   negop->icversion_data[1].major == 3) {
                        negop->icversion_data[0].major = 3;
                        negop->icversion_data[0].minor = 0;
                        negop->icversion_data[1].major = 3;
                        negop->icversion_data[1].minor = 0;
                } else {
                        negop->icversion_data[0].major = 1;
                        negop->icversion_data[0].minor = 0;
                        negop->icversion_data[1].major = 1;
                        negop->icversion_data[1].minor = 0;
                }

                negop->icframe_vercnt = 1;
                negop->icmsg_vercnt = 1;
        }
}
EXPORT_SYMBOL(prep_negotiate_resp);

/**
 * chn_cb_negotiate() - Default handler for non IDE/SCSI/NETWORK
 * Hyper-V requests
 * @context: Pointer to argument structure.
 *
 * Set up the default handler for non device driver specific requests
 * from Hyper-V. This stub responds to the default negotiate messages
 * that come in for every non IDE/SCSI/Network request.
 * This behavior is normally overwritten in the hv_utils driver. That
 * driver handles requests like gracefull shutdown, heartbeats etc.
 *
 * Mainly used by Hyper-V drivers.
 */
void chn_cb_negotiate(void *context)
{
        struct vmbus_channel *channel = context;
        u8 *buf;
        u32 buflen, recvlen;
        u64 requestid;

        struct icmsg_hdr *icmsghdrp;
        struct icmsg_negotiate *negop = NULL;

        buflen = PAGE_SIZE;
        buf = kmalloc(buflen, GFP_ATOMIC);

        VmbusChannelRecvPacket(channel, buf, buflen, &recvlen, &requestid);

        if (recvlen > 0) {
                icmsghdrp = (struct icmsg_hdr *)&buf[
                        sizeof(struct vmbuspipe_hdr)];

                prep_negotiate_resp(icmsghdrp, negop, buf);

                icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
                        | ICMSGHDRFLAG_RESPONSE;

                VmbusChannelSendPacket(channel, buf,
                                       recvlen, requestid,
                                       VmbusPacketTypeDataInBand, 0);
        }

        kfree(buf);
}
EXPORT_SYMBOL(chn_cb_negotiate);

/*
 * Function table used for message responses for non IDE/SCSI/Network type
 * messages. (Such as KVP/Shutdown etc)
 */
struct hyperv_service_callback hv_cb_utils[MAX_MSG_TYPES] = {
        /* 0E0B6031-5213-4934-818B-38D90CED39DB */
        /* Shutdown */
        {
                .msg_type = HV_SHUTDOWN_MSG,
                .data = {
                        0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
                        0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB
                },
                .callback = chn_cb_negotiate,
                .log_msg = "Shutdown channel functionality initialized"
        },

        /* {9527E630-D0AE-497b-ADCE-E80AB0175CAF} */
        /* TimeSync */
        {
                .msg_type = HV_TIMESYNC_MSG,
                .data = {
                        0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
                        0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf
                },
                .callback = chn_cb_negotiate,
                .log_msg = "Timesync channel functionality initialized"
        },
        /* {57164f39-9115-4e78-ab55-382f3bd5422d} */
        /* Heartbeat */
        {
                .msg_type = HV_HEARTBEAT_MSG,
                .data = {
                        0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
                        0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d
                },
                .callback = chn_cb_negotiate,
                .log_msg = "Heartbeat channel functionality initialized"
        },
};
EXPORT_SYMBOL(hv_cb_utils);

/*
 * AllocVmbusChannel - Allocate and initialize a vmbus channel object
 */
struct vmbus_channel *AllocVmbusChannel(void)
{
        struct vmbus_channel *channel;

        channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
        if (!channel)
                return NULL;

        spin_lock_init(&channel->inbound_lock);

        init_timer(&channel->poll_timer);
        channel->poll_timer.data = (unsigned long)channel;
        channel->poll_timer.function = VmbusChannelOnTimer;

        channel->ControlWQ = create_workqueue("hv_vmbus_ctl");
        if (!channel->ControlWQ) {
                kfree(channel);
                return NULL;
        }

        return channel;
}

/*
 * ReleaseVmbusChannel - Release the vmbus channel object itself
 */
static inline void ReleaseVmbusChannel(void *context)
{
        struct vmbus_channel *channel = context;

        DPRINT_DBG(VMBUS, "releasing channel (%p)", channel);
        destroy_workqueue(channel->ControlWQ);
        DPRINT_DBG(VMBUS, "channel released (%p)", channel);

        kfree(channel);
}

/*
 * FreeVmbusChannel - Release the resources used by the vmbus channel object
 */
void FreeVmbusChannel(struct vmbus_channel *Channel)
{
        del_timer_sync(&Channel->poll_timer);

        /*
         * We have to release the channel's workqueue/thread in the vmbus's
         * workqueue/thread context
         * ie we can't destroy ourselves.
         */
        osd_schedule_callback(gVmbusConnection.WorkQueue, ReleaseVmbusChannel,
                              Channel);
}


DECLARE_COMPLETION(hv_channel_ready);

/*
 * Count initialized channels, and ensure all channels are ready when hv_vmbus
 * module loading completes.
 */
static void count_hv_channel(void)
{
        static int counter;
        unsigned long flags;

        spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
        if (++counter == MAX_MSG_TYPES)
                complete(&hv_channel_ready);
        spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
}


/*
 * VmbusChannelProcessOffer - Process the offer by creating a channel/device
 * associated with this offer
 */
static void VmbusChannelProcessOffer(void *context)
{
        struct vmbus_channel *newChannel = context;
        struct vmbus_channel *channel;
        bool fNew = true;
        int ret;
        int cnt;
        unsigned long flags;

        /* Make sure this is a new offer */
        spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);

        list_for_each_entry(channel, &gVmbusConnection.ChannelList, ListEntry) {
                if (!memcmp(&channel->OfferMsg.Offer.InterfaceType,
                            &newChannel->OfferMsg.Offer.InterfaceType,
                            sizeof(struct hv_guid)) &&
                    !memcmp(&channel->OfferMsg.Offer.InterfaceInstance,
                            &newChannel->OfferMsg.Offer.InterfaceInstance,
                            sizeof(struct hv_guid))) {
                        fNew = false;
                        break;
                }
        }

        if (fNew)
                list_add_tail(&newChannel->ListEntry,
                              &gVmbusConnection.ChannelList);

        spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);

        if (!fNew) {
                DPRINT_DBG(VMBUS, "Ignoring duplicate offer for relid (%d)",
                           newChannel->OfferMsg.ChildRelId);
                FreeVmbusChannel(newChannel);
                return;
        }

        /*
         * Start the process of binding this offer to the driver
         * We need to set the DeviceObject field before calling
         * VmbusChildDeviceAdd()
         */
        newChannel->DeviceObject = VmbusChildDeviceCreate(
                &newChannel->OfferMsg.Offer.InterfaceType,
                &newChannel->OfferMsg.Offer.InterfaceInstance,
                newChannel);

        DPRINT_DBG(VMBUS, "child device object allocated - %p",
                   newChannel->DeviceObject);

        /*
         * Add the new device to the bus. This will kick off device-driver
         * binding which eventually invokes the device driver's AddDevice()
         * method.
         */
        ret = VmbusChildDeviceAdd(newChannel->DeviceObject);
        if (ret != 0) {
                DPRINT_ERR(VMBUS,
                           "unable to add child device object (relid %d)",
                           newChannel->OfferMsg.ChildRelId);

                spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
                list_del(&newChannel->ListEntry);
                spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);

                FreeVmbusChannel(newChannel);
        } else {
                /*
                 * This state is used to indicate a successful open
                 * so that when we do close the channel normally, we
                 * can cleanup properly
                 */
                newChannel->State = CHANNEL_OPEN_STATE;

                /* Open IC channels */
                for (cnt = 0; cnt < MAX_MSG_TYPES; cnt++) {
                        if (memcmp(&newChannel->OfferMsg.Offer.InterfaceType,
                                   &hv_cb_utils[cnt].data,
                                   sizeof(struct hv_guid)) == 0 &&
                                VmbusChannelOpen(newChannel, 2 * PAGE_SIZE,
                                                 2 * PAGE_SIZE, NULL, 0,
                                                 hv_cb_utils[cnt].callback,
                                                 newChannel) == 0) {
                                hv_cb_utils[cnt].channel = newChannel;
                                DPRINT_INFO(VMBUS, "%s",
                                                hv_cb_utils[cnt].log_msg);
                                count_hv_channel();
                        }
                }
        }
}

/*
 * VmbusChannelProcessRescindOffer - Rescind the offer by initiating a device removal
 */
static void VmbusChannelProcessRescindOffer(void *context)
{
        struct vmbus_channel *channel = context;

        VmbusChildDeviceRemove(channel->DeviceObject);
}

/*
 * VmbusChannelOnOffer - Handler for channel offers from vmbus in parent partition.
 *
 * We ignore all offers except network and storage offers. For each network and
 * storage offers, we create a channel object and queue a work item to the
 * channel object to process the offer synchronously
 */
static void VmbusChannelOnOffer(struct vmbus_channel_message_header *hdr)
{
        struct vmbus_channel_offer_channel *offer;
        struct vmbus_channel *newChannel;
        struct hv_guid *guidType;
        struct hv_guid *guidInstance;
        int i;
        int fSupported = 0;

        offer = (struct vmbus_channel_offer_channel *)hdr;
        for (i = 0; i < MAX_NUM_DEVICE_CLASSES_SUPPORTED; i++) {
                if (memcmp(&offer->Offer.InterfaceType,
                    &gSupportedDeviceClasses[i], sizeof(struct hv_guid)) == 0) {
                        fSupported = 1;
                        break;
                }
        }

        if (!fSupported) {
                DPRINT_DBG(VMBUS, "Ignoring channel offer notification for "
                           "child relid %d", offer->ChildRelId);
                return;
        }

        guidType = &offer->Offer.InterfaceType;
        guidInstance = &offer->Offer.InterfaceInstance;

        DPRINT_INFO(VMBUS, "Channel offer notification - "
                    "child relid %d monitor id %d allocated %d, "
                    "type {%02x%02x%02x%02x-%02x%02x-%02x%02x-"
                    "%02x%02x%02x%02x%02x%02x%02x%02x} "
                    "instance {%02x%02x%02x%02x-%02x%02x-%02x%02x-"
                    "%02x%02x%02x%02x%02x%02x%02x%02x}",
                    offer->ChildRelId, offer->MonitorId,
                    offer->MonitorAllocated,
                    guidType->data[3], guidType->data[2],
                    guidType->data[1], guidType->data[0],
                    guidType->data[5], guidType->data[4],
                    guidType->data[7], guidType->data[6],
                    guidType->data[8], guidType->data[9],
                    guidType->data[10], guidType->data[11],
                    guidType->data[12], guidType->data[13],
                    guidType->data[14], guidType->data[15],
                    guidInstance->data[3], guidInstance->data[2],
                    guidInstance->data[1], guidInstance->data[0],
                    guidInstance->data[5], guidInstance->data[4],
                    guidInstance->data[7], guidInstance->data[6],
                    guidInstance->data[8], guidInstance->data[9],
                    guidInstance->data[10], guidInstance->data[11],
                    guidInstance->data[12], guidInstance->data[13],
                    guidInstance->data[14], guidInstance->data[15]);

        /* Allocate the channel object and save this offer. */
        newChannel = AllocVmbusChannel();
        if (!newChannel) {
                DPRINT_ERR(VMBUS, "unable to allocate channel object");
                return;
        }

        DPRINT_DBG(VMBUS, "channel object allocated - %p", newChannel);

        memcpy(&newChannel->OfferMsg, offer,
               sizeof(struct vmbus_channel_offer_channel));
        newChannel->MonitorGroup = (u8)offer->MonitorId / 32;
        newChannel->MonitorBit = (u8)offer->MonitorId % 32;

        /* TODO: Make sure the offer comes from our parent partition */
        osd_schedule_callback(newChannel->ControlWQ, VmbusChannelProcessOffer,
                              newChannel);
}

/*
 * VmbusChannelOnOfferRescind - Rescind offer handler.
 *
 * We queue a work item to process this offer synchronously
 */
static void VmbusChannelOnOfferRescind(struct vmbus_channel_message_header *hdr)
{
        struct vmbus_channel_rescind_offer *rescind;
        struct vmbus_channel *channel;

        rescind = (struct vmbus_channel_rescind_offer *)hdr;
        channel = GetChannelFromRelId(rescind->ChildRelId);
        if (channel == NULL) {
                DPRINT_DBG(VMBUS, "channel not found for relId %d",
                           rescind->ChildRelId);
                return;
        }

        osd_schedule_callback(channel->ControlWQ,
                              VmbusChannelProcessRescindOffer,
                              channel);
}

/*
 * VmbusChannelOnOffersDelivered - This is invoked when all offers have been delivered.
 *
 * Nothing to do here.
 */
static void VmbusChannelOnOffersDelivered(
                        struct vmbus_channel_message_header *hdr)
{
}

/*
 * VmbusChannelOnOpenResult - Open result handler.
 *
 * This is invoked when we received a response to our channel open request.
 * Find the matching request, copy the response and signal the requesting
 * thread.
 */
static void VmbusChannelOnOpenResult(struct vmbus_channel_message_header *hdr)
{
        struct vmbus_channel_open_result *result;
        struct list_head *curr;
        struct vmbus_channel_msginfo *msgInfo;
        struct vmbus_channel_message_header *requestHeader;
        struct vmbus_channel_open_channel *openMsg;
        unsigned long flags;

        result = (struct vmbus_channel_open_result *)hdr;
        DPRINT_DBG(VMBUS, "vmbus open result - %d", result->Status);

        /*
         * Find the open msg, copy the result and signal/unblock the wait event
         */
        spin_lock_irqsave(&gVmbusConnection.channelmsg_lock, flags);

        list_for_each(curr, &gVmbusConnection.ChannelMsgList) {
                msgInfo = (struct vmbus_channel_msginfo *)curr;
                requestHeader = (struct vmbus_channel_message_header *)msgInfo->Msg;

                if (requestHeader->MessageType == ChannelMessageOpenChannel) {
                        openMsg = (struct vmbus_channel_open_channel *)msgInfo->Msg;
                        if (openMsg->ChildRelId == result->ChildRelId &&
                            openMsg->OpenId == result->OpenId) {
                                memcpy(&msgInfo->Response.OpenResult,
                                       result,
                                       sizeof(struct vmbus_channel_open_result));
                                osd_WaitEventSet(msgInfo->WaitEvent);
                                break;
                        }
                }
        }
        spin_unlock_irqrestore(&gVmbusConnection.channelmsg_lock, flags);
}

/*
 * VmbusChannelOnGpadlCreated - GPADL created handler.
 *
 * This is invoked when we received a response to our gpadl create request.
 * Find the matching request, copy the response and signal the requesting
 * thread.
 */
static void VmbusChannelOnGpadlCreated(struct vmbus_channel_message_header *hdr)
{
        struct vmbus_channel_gpadl_created *gpadlCreated;
        struct list_head *curr;
        struct vmbus_channel_msginfo *msgInfo;
        struct vmbus_channel_message_header *requestHeader;
        struct vmbus_channel_gpadl_header *gpadlHeader;
        unsigned long flags;

        gpadlCreated = (struct vmbus_channel_gpadl_created *)hdr;
        DPRINT_DBG(VMBUS, "vmbus gpadl created result - %d",
                   gpadlCreated->CreationStatus);

        /*
         * Find the establish msg, copy the result and signal/unblock the wait
         * event
         */
        spin_lock_irqsave(&gVmbusConnection.channelmsg_lock, flags);

        list_for_each(curr, &gVmbusConnection.ChannelMsgList) {
                msgInfo = (struct vmbus_channel_msginfo *)curr;
                requestHeader = (struct vmbus_channel_message_header *)msgInfo->Msg;

                if (requestHeader->MessageType == ChannelMessageGpadlHeader) {
                        gpadlHeader = (struct vmbus_channel_gpadl_header *)requestHeader;

                        if ((gpadlCreated->ChildRelId ==
                             gpadlHeader->ChildRelId) &&
                            (gpadlCreated->Gpadl == gpadlHeader->Gpadl)) {
                                memcpy(&msgInfo->Response.GpadlCreated,
                                       gpadlCreated,
                                       sizeof(struct vmbus_channel_gpadl_created));
                                osd_WaitEventSet(msgInfo->WaitEvent);
                                break;
                        }
                }
        }
        spin_unlock_irqrestore(&gVmbusConnection.channelmsg_lock, flags);
}

/*
 * VmbusChannelOnGpadlTorndown - GPADL torndown handler.
 *
 * This is invoked when we received a response to our gpadl teardown request.
 * Find the matching request, copy the response and signal the requesting
 * thread.
 */
static void VmbusChannelOnGpadlTorndown(
                        struct vmbus_channel_message_header *hdr)
{
        struct vmbus_channel_gpadl_torndown *gpadlTorndown;
        struct list_head *curr;
        struct vmbus_channel_msginfo *msgInfo;
        struct vmbus_channel_message_header *requestHeader;
        struct vmbus_channel_gpadl_teardown *gpadlTeardown;
        unsigned long flags;

        gpadlTorndown = (struct vmbus_channel_gpadl_torndown *)hdr;

        /*
         * Find the open msg, copy the result and signal/unblock the wait event
         */
        spin_lock_irqsave(&gVmbusConnection.channelmsg_lock, flags);

        list_for_each(curr, &gVmbusConnection.ChannelMsgList) {
                msgInfo = (struct vmbus_channel_msginfo *)curr;
                requestHeader = (struct vmbus_channel_message_header *)msgInfo->Msg;

                if (requestHeader->MessageType == ChannelMessageGpadlTeardown) {
                        gpadlTeardown = (struct vmbus_channel_gpadl_teardown *)requestHeader;

                        if (gpadlTorndown->Gpadl == gpadlTeardown->Gpadl) {
                                memcpy(&msgInfo->Response.GpadlTorndown,
                                       gpadlTorndown,
                                       sizeof(struct vmbus_channel_gpadl_torndown));
                                osd_WaitEventSet(msgInfo->WaitEvent);
                                break;
                        }
                }
        }
        spin_unlock_irqrestore(&gVmbusConnection.channelmsg_lock, flags);
}

/*
 * VmbusChannelOnVersionResponse - Version response handler
 *
 * This is invoked when we received a response to our initiate contact request.
 * Find the matching request, copy the response and signal the requesting
 * thread.
 */
static void VmbusChannelOnVersionResponse(
                struct vmbus_channel_message_header *hdr)
{
        struct list_head *curr;
        struct vmbus_channel_msginfo *msgInfo;
        struct vmbus_channel_message_header *requestHeader;
        struct vmbus_channel_initiate_contact *initiate;
        struct vmbus_channel_version_response *versionResponse;
        unsigned long flags;

        versionResponse = (struct vmbus_channel_version_response *)hdr;
        spin_lock_irqsave(&gVmbusConnection.channelmsg_lock, flags);

        list_for_each(curr, &gVmbusConnection.ChannelMsgList) {
                msgInfo = (struct vmbus_channel_msginfo *)curr;
                requestHeader = (struct vmbus_channel_message_header *)msgInfo->Msg;

                if (requestHeader->MessageType ==
                    ChannelMessageInitiateContact) {
                        initiate = (struct vmbus_channel_initiate_contact *)requestHeader;
                        memcpy(&msgInfo->Response.VersionResponse,
                              versionResponse,
                              sizeof(struct vmbus_channel_version_response));
                        osd_WaitEventSet(msgInfo->WaitEvent);
                }
        }
        spin_unlock_irqrestore(&gVmbusConnection.channelmsg_lock, flags);
}

/* Channel message dispatch table */
static struct vmbus_channel_message_table_entry
        gChannelMessageTable[ChannelMessageCount] = {
        {ChannelMessageInvalid,                 NULL},
        {ChannelMessageOfferChannel,            VmbusChannelOnOffer},
        {ChannelMessageRescindChannelOffer,     VmbusChannelOnOfferRescind},
        {ChannelMessageRequestOffers,           NULL},
        {ChannelMessageAllOffersDelivered,      VmbusChannelOnOffersDelivered},
        {ChannelMessageOpenChannel,             NULL},
        {ChannelMessageOpenChannelResult,       VmbusChannelOnOpenResult},
        {ChannelMessageCloseChannel,            NULL},
        {ChannelMessageGpadlHeader,             NULL},
        {ChannelMessageGpadlBody,               NULL},
        {ChannelMessageGpadlCreated,            VmbusChannelOnGpadlCreated},
        {ChannelMessageGpadlTeardown,           NULL},
        {ChannelMessageGpadlTorndown,           VmbusChannelOnGpadlTorndown},
        {ChannelMessageRelIdReleased,           NULL},
        {ChannelMessageInitiateContact,         NULL},
        {ChannelMessageVersionResponse,         VmbusChannelOnVersionResponse},
        {ChannelMessageUnload,                  NULL},
};

/*
 * VmbusOnChannelMessage - Handler for channel protocol messages.
 *
 * This is invoked in the vmbus worker thread context.
 */
void VmbusOnChannelMessage(void *Context)
{
        struct hv_message *msg = Context;
        struct vmbus_channel_message_header *hdr;
        int size;

        hdr = (struct vmbus_channel_message_header *)msg->u.Payload;
        size = msg->Header.PayloadSize;

        DPRINT_DBG(VMBUS, "message type %d size %d", hdr->MessageType, size);

        if (hdr->MessageType >= ChannelMessageCount) {
                DPRINT_ERR(VMBUS,
                           "Received invalid channel message type %d size %d",
                           hdr->MessageType, size);
                print_hex_dump_bytes("", DUMP_PREFIX_NONE,
                                     (unsigned char *)msg->u.Payload, size);
                kfree(msg);
                return;
        }

        if (gChannelMessageTable[hdr->MessageType].messageHandler)
                gChannelMessageTable[hdr->MessageType].messageHandler(hdr);
        else
                DPRINT_ERR(VMBUS, "Unhandled channel message type %d",
                           hdr->MessageType);

        /* Free the msg that was allocated in VmbusOnMsgDPC() */
        kfree(msg);
}

/*
 * VmbusChannelRequestOffers - Send a request to get all our pending offers.
 */
int VmbusChannelRequestOffers(void)
{
        struct vmbus_channel_message_header *msg;
        struct vmbus_channel_msginfo *msgInfo;
        int ret;

        msgInfo = kmalloc(sizeof(*msgInfo) +
                          sizeof(struct vmbus_channel_message_header),
                          GFP_KERNEL);
        if (!msgInfo)
                return -ENOMEM;

        msgInfo->WaitEvent = osd_WaitEventCreate();
        if (!msgInfo->WaitEvent) {
                kfree(msgInfo);
                return -ENOMEM;
        }

        msg = (struct vmbus_channel_message_header *)msgInfo->Msg;

        msg->MessageType = ChannelMessageRequestOffers;

        /*SpinlockAcquire(gVmbusConnection.channelMsgLock);
        INSERT_TAIL_LIST(&gVmbusConnection.channelMsgList,
                         &msgInfo->msgListEntry);
        SpinlockRelease(gVmbusConnection.channelMsgLock);*/

        ret = VmbusPostMessage(msg,
                               sizeof(struct vmbus_channel_message_header));
        if (ret != 0) {
                DPRINT_ERR(VMBUS, "Unable to request offers - %d", ret);

                /*SpinlockAcquire(gVmbusConnection.channelMsgLock);
                REMOVE_ENTRY_LIST(&msgInfo->msgListEntry);
                SpinlockRelease(gVmbusConnection.channelMsgLock);*/

                goto Cleanup;
        }
        /* osd_WaitEventWait(msgInfo->waitEvent); */

        /*SpinlockAcquire(gVmbusConnection.channelMsgLock);
        REMOVE_ENTRY_LIST(&msgInfo->msgListEntry);
        SpinlockRelease(gVmbusConnection.channelMsgLock);*/


Cleanup:
        if (msgInfo) {
                kfree(msgInfo->WaitEvent);
                kfree(msgInfo);
        }

        return ret;
}

/*
 * VmbusChannelReleaseUnattachedChannels - Release channels that are
 * unattached/unconnected ie (no drivers associated)
 */
void VmbusChannelReleaseUnattachedChannels(void)
{
        struct vmbus_channel *channel, *pos;
        struct vmbus_channel *start = NULL;
        unsigned long flags;

        spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);

        list_for_each_entry_safe(channel, pos, &gVmbusConnection.ChannelList,
                                 ListEntry) {
                if (channel == start)
                        break;

                if (!channel->DeviceObject->Driver) {
                        list_del(&channel->ListEntry);
                        DPRINT_INFO(VMBUS,
                                    "Releasing unattached device object %p",
                                    channel->DeviceObject);

                        VmbusChildDeviceRemove(channel->DeviceObject);
                        FreeVmbusChannel(channel);
                } else {
                        if (!start)
                                start = channel;
                }
        }

        spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
}

/* eof */