--- /dev/null
+/*
+ * 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>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/completion.h>
+#include <linux/hyperv.h>
+
+#include "hyperv_vmbus.h"
+
+/**
+ * vmbus_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.
+ *
+ * The fw_version specifies the framework version that
+ * we can support and srv_version specifies the service
+ * version we can support.
+ *
+ * Mainly used by Hyper-V drivers.
+ */
+bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
+ struct icmsg_negotiate *negop, u8 *buf,
+ int fw_version, int srv_version)
+{
+ int icframe_major, icframe_minor;
+ int icmsg_major, icmsg_minor;
+ int fw_major, fw_minor;
+ int srv_major, srv_minor;
+ int i;
+ bool found_match = false;
+
+ icmsghdrp->icmsgsize = 0x10;
+ fw_major = (fw_version >> 16);
+ fw_minor = (fw_version & 0xFFFF);
+
+ srv_major = (srv_version >> 16);
+ srv_minor = (srv_version & 0xFFFF);
+
+ negop = (struct icmsg_negotiate *)&buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ icframe_major = negop->icframe_vercnt;
+ icframe_minor = 0;
+
+ icmsg_major = negop->icmsg_vercnt;
+ icmsg_minor = 0;
+
+ /*
+ * Select the framework version number we will
+ * support.
+ */
+
+ for (i = 0; i < negop->icframe_vercnt; i++) {
+ if ((negop->icversion_data[i].major == fw_major) &&
+ (negop->icversion_data[i].minor == fw_minor)) {
+ icframe_major = negop->icversion_data[i].major;
+ icframe_minor = negop->icversion_data[i].minor;
+ found_match = true;
+ }
+ }
+
+ if (!found_match)
+ goto fw_error;
+
+ found_match = false;
+
+ for (i = negop->icframe_vercnt;
+ (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) {
+ if ((negop->icversion_data[i].major == srv_major) &&
+ (negop->icversion_data[i].minor == srv_minor)) {
+ icmsg_major = negop->icversion_data[i].major;
+ icmsg_minor = negop->icversion_data[i].minor;
+ found_match = true;
+ }
+ }
+
+ /*
+ * Respond with the framework and service
+ * version numbers we can support.
+ */
+
+fw_error:
+ if (!found_match) {
+ negop->icframe_vercnt = 0;
+ negop->icmsg_vercnt = 0;
+ } else {
+ negop->icframe_vercnt = 1;
+ negop->icmsg_vercnt = 1;
+ }
+
+ negop->icversion_data[0].major = icframe_major;
+ negop->icversion_data[0].minor = icframe_minor;
+ negop->icversion_data[1].major = icmsg_major;
+ negop->icversion_data[1].minor = icmsg_minor;
+ return found_match;
+}
+
+EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
+
+/*
+ * alloc_channel - Allocate and initialize a vmbus channel object
+ */
+static struct vmbus_channel *alloc_channel(void)
+{
+ static atomic_t chan_num = ATOMIC_INIT(0);
+ struct vmbus_channel *channel;
+
+ channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
+ if (!channel)
+ return NULL;
+
+ channel->id = atomic_inc_return(&chan_num);
+ spin_lock_init(&channel->inbound_lock);
+ spin_lock_init(&channel->lock);
+
+ INIT_LIST_HEAD(&channel->sc_list);
+ INIT_LIST_HEAD(&channel->percpu_list);
+
+ return channel;
+}
+
+/*
+ * free_channel - Release the resources used by the vmbus channel object
+ */
+static void free_channel(struct vmbus_channel *channel)
+{
+ kfree(channel);
+}
+
+static void percpu_channel_enq(void *arg)
+{
+ struct vmbus_channel *channel = arg;
+ int cpu = smp_processor_id();
+
+ list_add_tail(&channel->percpu_list, &hv_context.percpu_list[cpu]);
+}
+
+static void percpu_channel_deq(void *arg)
+{
+ struct vmbus_channel *channel = arg;
+
+ list_del(&channel->percpu_list);
+}
+
+
+void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+{
+ struct vmbus_channel_relid_released msg;
+ unsigned long flags;
+ struct vmbus_channel *primary_channel;
+
+ memset(&msg, 0, sizeof(struct vmbus_channel_relid_released));
+ msg.child_relid = relid;
+ msg.header.msgtype = CHANNELMSG_RELID_RELEASED;
+ vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released));
+
+ if (channel == NULL)
+ return;
+
+ if (channel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(channel->target_cpu,
+ percpu_channel_deq, channel, true);
+ } else {
+ percpu_channel_deq(channel);
+ put_cpu();
+ }
+
+ if (channel->primary_channel == NULL) {
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+ list_del(&channel->listentry);
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+ } else {
+ primary_channel = channel->primary_channel;
+ spin_lock_irqsave(&primary_channel->lock, flags);
+ list_del(&channel->sc_list);
+ spin_unlock_irqrestore(&primary_channel->lock, flags);
+ }
+ free_channel(channel);
+}
+
+void vmbus_free_channels(void)
+{
+ struct vmbus_channel *channel;
+
+ list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
+ vmbus_device_unregister(channel->device_obj);
+ free_channel(channel);
+ }
+}
+
+/*
+ * vmbus_process_offer - Process the offer by creating a channel/device
+ * associated with this offer
+ */
+static void vmbus_process_offer(struct vmbus_channel *newchannel)
+{
+ struct vmbus_channel *channel;
+ bool fnew = true;
+ bool enq = false;
+ unsigned long flags;
+
+ /* Make sure this is a new offer */
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+
+ list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
+ if (!uuid_le_cmp(channel->offermsg.offer.if_type,
+ newchannel->offermsg.offer.if_type) &&
+ !uuid_le_cmp(channel->offermsg.offer.if_instance,
+ newchannel->offermsg.offer.if_instance)) {
+ fnew = false;
+ break;
+ }
+ }
+
+ if (fnew) {
+ list_add_tail(&newchannel->listentry,
+ &vmbus_connection.chn_list);
+ enq = true;
+ }
+
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+
+ if (enq) {
+ if (newchannel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(newchannel->target_cpu,
+ percpu_channel_enq,
+ newchannel, true);
+ } else {
+ percpu_channel_enq(newchannel);
+ put_cpu();
+ }
+ }
+ if (!fnew) {
+ /*
+ * Check to see if this is a sub-channel.
+ */
+ if (newchannel->offermsg.offer.sub_channel_index != 0) {
+ /*
+ * Process the sub-channel.
+ */
+ newchannel->primary_channel = channel;
+ spin_lock_irqsave(&channel->lock, flags);
+ list_add_tail(&newchannel->sc_list, &channel->sc_list);
+ spin_unlock_irqrestore(&channel->lock, flags);
+
+ if (newchannel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(newchannel->target_cpu,
+ percpu_channel_enq,
+ newchannel, true);
+ } else {
+ percpu_channel_enq(newchannel);
+ put_cpu();
+ }
+
+ newchannel->state = CHANNEL_OPEN_STATE;
+ channel->num_sc++;
+ if (channel->sc_creation_callback != NULL)
+ channel->sc_creation_callback(newchannel);
+
+ return;
+ }
+
+ goto err_free_chan;
+ }
+
+ /*
+ * 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;
+
+ /*
+ * Start the process of binding this offer to the driver
+ * We need to set the DeviceObject field before calling
+ * vmbus_child_dev_add()
+ */
+ newchannel->device_obj = vmbus_device_create(
+ &newchannel->offermsg.offer.if_type,
+ &newchannel->offermsg.offer.if_instance,
+ newchannel);
+ if (!newchannel->device_obj)
+ goto err_deq_chan;
+
+ /*
+ * Add the new device to the bus. This will kick off device-driver
+ * binding which eventually invokes the device driver's AddDevice()
+ * method.
+ */
+ if (vmbus_device_register(newchannel->device_obj) != 0) {
+ pr_err("unable to add child device object (relid %d)\n",
+ newchannel->offermsg.child_relid);
+ kfree(newchannel->device_obj);
+ goto err_deq_chan;
+ }
+ return;
+
+err_deq_chan:
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+ list_del(&newchannel->listentry);
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+
+ if (newchannel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(newchannel->target_cpu,
+ percpu_channel_deq, newchannel, true);
+ } else {
+ percpu_channel_deq(newchannel);
+ put_cpu();
+ }
+
+err_free_chan:
+ free_channel(newchannel);
+}
+
+enum {
+ IDE = 0,
+ SCSI,
+ NIC,
+ MAX_PERF_CHN,
+};
+
+/*
+ * This is an array of device_ids (device types) that are performance critical.
+ * We attempt to distribute the interrupt load for these devices across
+ * all available CPUs.
+ */
+static const struct hv_vmbus_device_id hp_devs[] = {
+ /* IDE */
+ { HV_IDE_GUID, },
+ /* Storage - SCSI */
+ { HV_SCSI_GUID, },
+ /* Network */
+ { HV_NIC_GUID, },
+ /* NetworkDirect Guest RDMA */
+ { HV_ND_GUID, },
+};
+
+
+/*
+ * We use this state to statically distribute the channel interrupt load.
+ */
+static u32 next_vp;
+
+/*
+ * Starting with Win8, we can statically distribute the incoming
+ * channel interrupt load by binding a channel to VCPU. We
+ * implement here a simple round robin scheme for distributing
+ * the interrupt load.
+ * We will bind channels that are not performance critical to cpu 0 and
+ * performance critical channels (IDE, SCSI and Network) will be uniformly
+ * distributed across all available CPUs.
+ */
+static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid)
+{
+ u32 cur_cpu;
+ int i;
+ bool perf_chn = false;
+ u32 max_cpus = num_online_cpus();
+
+ for (i = IDE; i < MAX_PERF_CHN; i++) {
+ if (!memcmp(type_guid->b, hp_devs[i].guid,
+ sizeof(uuid_le))) {
+ perf_chn = true;
+ break;
+ }
+ }
+ if ((vmbus_proto_version == VERSION_WS2008) ||
+ (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) {
+ /*
+ * Prior to win8, all channel interrupts are
+ * delivered on cpu 0.
+ * Also if the channel is not a performance critical
+ * channel, bind it to cpu 0.
+ */
+ channel->target_cpu = 0;
+ channel->target_vp = 0;
+ return;
+ }
+ cur_cpu = (++next_vp % max_cpus);
+ channel->target_cpu = cur_cpu;
+ channel->target_vp = hv_context.vp_index[cur_cpu];
+}
+
+/*
+ * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
+ *
+ */
+static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_offer_channel *offer;
+ struct vmbus_channel *newchannel;
+
+ offer = (struct vmbus_channel_offer_channel *)hdr;
+
+ /* Allocate the channel object and save this offer. */
+ newchannel = alloc_channel();
+ if (!newchannel) {
+ pr_err("Unable to allocate channel object\n");
+ return;
+ }
+
+ /*
+ * By default we setup state to enable batched
+ * reading. A specific service can choose to
+ * disable this prior to opening the channel.
+ */
+ newchannel->batched_reading = true;
+
+ /*
+ * Setup state for signalling the host.
+ */
+ newchannel->sig_event = (struct hv_input_signal_event *)
+ (ALIGN((unsigned long)
+ &newchannel->sig_buf,
+ HV_HYPERCALL_PARAM_ALIGN));
+
+ newchannel->sig_event->connectionid.asu32 = 0;
+ newchannel->sig_event->connectionid.u.id = VMBUS_EVENT_CONNECTION_ID;
+ newchannel->sig_event->flag_number = 0;
+ newchannel->sig_event->rsvdz = 0;
+
+ if (vmbus_proto_version != VERSION_WS2008) {
+ newchannel->is_dedicated_interrupt =
+ (offer->is_dedicated_interrupt != 0);
+ newchannel->sig_event->connectionid.u.id =
+ offer->connection_id;
+ }
+
+ init_vp_index(newchannel, &offer->offer.if_type);
+
+ memcpy(&newchannel->offermsg, offer,
+ sizeof(struct vmbus_channel_offer_channel));
+ newchannel->monitor_grp = (u8)offer->monitorid / 32;
+ newchannel->monitor_bit = (u8)offer->monitorid % 32;
+
+ vmbus_process_offer(newchannel);
+}
+
+/*
+ * vmbus_onoffer_rescind - Rescind offer handler.
+ *
+ * We queue a work item to process this offer synchronously
+ */
+static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_rescind_offer *rescind;
+ struct vmbus_channel *channel;
+ unsigned long flags;
+ struct device *dev;
+
+ rescind = (struct vmbus_channel_rescind_offer *)hdr;
+ channel = relid2channel(rescind->child_relid);
+
+ if (channel == NULL) {
+ hv_process_channel_removal(NULL, rescind->child_relid);
+ return;
+ }
+
+ spin_lock_irqsave(&channel->lock, flags);
+ channel->rescind = true;
+ spin_unlock_irqrestore(&channel->lock, flags);
+
+ if (channel->device_obj) {
+ /*
+ * We will have to unregister this device from the
+ * driver core.
+ */
+ dev = get_device(&channel->device_obj->device);
+ if (dev) {
+ vmbus_device_unregister(channel->device_obj);
+ put_device(dev);
+ }
+ } else {
+ hv_process_channel_removal(channel,
+ channel->offermsg.child_relid);
+ }
+}
+
+/*
+ * vmbus_onoffers_delivered -
+ * This is invoked when all offers have been delivered.
+ *
+ * Nothing to do here.
+ */
+static void vmbus_onoffers_delivered(
+ struct vmbus_channel_message_header *hdr)
+{
+}
+
+/*
+ * vmbus_onopen_result - 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 vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_open_result *result;
+ 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;
+
+ /*
+ * Find the open msg, copy the result and signal/unblock the wait event
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
+ openmsg =
+ (struct vmbus_channel_open_channel *)msginfo->msg;
+ if (openmsg->child_relid == result->child_relid &&
+ openmsg->openid == result->openid) {
+ memcpy(&msginfo->response.open_result,
+ result,
+ sizeof(
+ struct vmbus_channel_open_result));
+ complete(&msginfo->waitevent);
+ break;
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/*
+ * vmbus_ongpadl_created - 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 vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_gpadl_created *gpadlcreated;
+ 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;
+
+ /*
+ * Find the establish msg, copy the result and signal/unblock the wait
+ * event
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
+ gpadlheader =
+ (struct vmbus_channel_gpadl_header *)requestheader;
+
+ if ((gpadlcreated->child_relid ==
+ gpadlheader->child_relid) &&
+ (gpadlcreated->gpadl == gpadlheader->gpadl)) {
+ memcpy(&msginfo->response.gpadl_created,
+ gpadlcreated,
+ sizeof(
+ struct vmbus_channel_gpadl_created));
+ complete(&msginfo->waitevent);
+ break;
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/*
+ * vmbus_ongpadl_torndown - 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 vmbus_ongpadl_torndown(
+ struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_gpadl_torndown *gpadl_torndown;
+ struct vmbus_channel_msginfo *msginfo;
+ struct vmbus_channel_message_header *requestheader;
+ struct vmbus_channel_gpadl_teardown *gpadl_teardown;
+ unsigned long flags;
+
+ gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
+
+ /*
+ * Find the open msg, copy the result and signal/unblock the wait event
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
+ gpadl_teardown =
+ (struct vmbus_channel_gpadl_teardown *)requestheader;
+
+ if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
+ memcpy(&msginfo->response.gpadl_torndown,
+ gpadl_torndown,
+ sizeof(
+ struct vmbus_channel_gpadl_torndown));
+ complete(&msginfo->waitevent);
+ break;
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/*
+ * vmbus_onversion_response - 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 vmbus_onversion_response(
+ struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_msginfo *msginfo;
+ struct vmbus_channel_message_header *requestheader;
+ struct vmbus_channel_version_response *version_response;
+ unsigned long flags;
+
+ version_response = (struct vmbus_channel_version_response *)hdr;
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype ==
+ CHANNELMSG_INITIATE_CONTACT) {
+ memcpy(&msginfo->response.version_response,
+ version_response,
+ sizeof(struct vmbus_channel_version_response));
+ complete(&msginfo->waitevent);
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/* Channel message dispatch table */
+struct vmbus_channel_message_table_entry
+ channel_message_table[CHANNELMSG_COUNT] = {
+ {CHANNELMSG_INVALID, 0, NULL},
+ {CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer},
+ {CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind},
+ {CHANNELMSG_REQUESTOFFERS, 0, NULL},
+ {CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered},
+ {CHANNELMSG_OPENCHANNEL, 0, NULL},
+ {CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result},
+ {CHANNELMSG_CLOSECHANNEL, 0, NULL},
+ {CHANNELMSG_GPADL_HEADER, 0, NULL},
+ {CHANNELMSG_GPADL_BODY, 0, NULL},
+ {CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created},
+ {CHANNELMSG_GPADL_TEARDOWN, 0, NULL},
+ {CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown},
+ {CHANNELMSG_RELID_RELEASED, 0, NULL},
+ {CHANNELMSG_INITIATE_CONTACT, 0, NULL},
+ {CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response},
+ {CHANNELMSG_UNLOAD, 0, NULL},
+};
+
+/*
+ * vmbus_onmessage - Handler for channel protocol messages.
+ *
+ * This is invoked in the vmbus worker thread context.
+ */
+void vmbus_onmessage(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.payload_size;
+
+ if (hdr->msgtype >= CHANNELMSG_COUNT) {
+ pr_err("Received invalid channel message type %d size %d\n",
+ hdr->msgtype, size);
+ print_hex_dump_bytes("", DUMP_PREFIX_NONE,
+ (unsigned char *)msg->u.payload, size);
+ return;
+ }
+
+ if (channel_message_table[hdr->msgtype].message_handler)
+ channel_message_table[hdr->msgtype].message_handler(hdr);
+ else
+ pr_err("Unhandled channel message type %d\n", hdr->msgtype);
+}
+
+/*
+ * vmbus_request_offers - Send a request to get all our pending offers.
+ */
+int vmbus_request_offers(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;
+
+ msg = (struct vmbus_channel_message_header *)msginfo->msg;
+
+ msg->msgtype = CHANNELMSG_REQUESTOFFERS;
+
+
+ ret = vmbus_post_msg(msg,
+ sizeof(struct vmbus_channel_message_header));
+ if (ret != 0) {
+ pr_err("Unable to request offers - %d\n", ret);
+
+ goto cleanup;
+ }
+
+cleanup:
+ kfree(msginfo);
+
+ return ret;
+}
+
+/*
+ * Retrieve the (sub) channel on which to send an outgoing request.
+ * When a primary channel has multiple sub-channels, we try to
+ * distribute the load equally amongst all available channels.
+ */
+struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary)
+{
+ struct list_head *cur, *tmp;
+ int cur_cpu;
+ struct vmbus_channel *cur_channel;
+ struct vmbus_channel *outgoing_channel = primary;
+ int next_channel;
+ int i = 1;
+
+ if (list_empty(&primary->sc_list))
+ return outgoing_channel;
+
+ next_channel = primary->next_oc++;
+
+ if (next_channel > (primary->num_sc)) {
+ primary->next_oc = 0;
+ return outgoing_channel;
+ }
+
+ cur_cpu = hv_context.vp_index[get_cpu()];
+ put_cpu();
+ list_for_each_safe(cur, tmp, &primary->sc_list) {
+ cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
+ if (cur_channel->state != CHANNEL_OPENED_STATE)
+ continue;
+
+ if (cur_channel->target_vp == cur_cpu)
+ return cur_channel;
+
+ if (i == next_channel)
+ return cur_channel;
+
+ i++;
+ }
+
+ return outgoing_channel;
+}
+EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel);
+
+static void invoke_sc_cb(struct vmbus_channel *primary_channel)
+{
+ struct list_head *cur, *tmp;
+ struct vmbus_channel *cur_channel;
+
+ if (primary_channel->sc_creation_callback == NULL)
+ return;
+
+ list_for_each_safe(cur, tmp, &primary_channel->sc_list) {
+ cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
+
+ primary_channel->sc_creation_callback(cur_channel);
+ }
+}
+
+void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
+ void (*sc_cr_cb)(struct vmbus_channel *new_sc))
+{
+ primary_channel->sc_creation_callback = sc_cr_cb;
+}
+EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback);
+
+bool vmbus_are_subchannels_present(struct vmbus_channel *primary)
+{
+ bool ret;
+
+ ret = !list_empty(&primary->sc_list);
+
+ if (ret) {
+ /*
+ * Invoke the callback on sub-channel creation.
+ * This will present a uniform interface to the
+ * clients.
+ */
+ invoke_sc_cb(primary);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present);
Code Review / kvmfornfv.git / blobdiff