drivers/staging/hv/vmbus.c

   1 /*
   2  * Copyright (c) 2009, Microsoft Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  *
  21  */
  22 #include <linux/kernel.h>
  23 #include <linux/mm.h>
  24 #include <linux/slab.h>
  25 #include "osd.h"
  26 #include "logging.h"
  27 #include "version_info.h"
  28 #include "vmbus_private.h"
  29
  30 static const char *gDriverName = "vmbus";
  31
  32 /*
  33  * Windows vmbus does not defined this.
  34  * We defined this to be consistent with other devices
  35  */
  36 /* {c5295816-f63a-4d5f-8d1a-4daf999ca185} */
  37 static const struct hv_guid gVmbusDeviceType = {
  38         .data = {
  39                 0x16, 0x58, 0x29, 0xc5, 0x3a, 0xf6, 0x5f, 0x4d,
  40                 0x8d, 0x1a, 0x4d, 0xaf, 0x99, 0x9c, 0xa1, 0x85
  41         }
  42 };
  43
  44 /* {ac3760fc-9adf-40aa-9427-a70ed6de95c5} */
  45 static const struct hv_guid gVmbusDeviceId = {
  46         .data = {
  47                 0xfc, 0x60, 0x37, 0xac, 0xdf, 0x9a, 0xaa, 0x40,
  48                 0x94, 0x27, 0xa7, 0x0e, 0xd6, 0xde, 0x95, 0xc5
  49         }
  50 };
  51
  52 static struct hv_driver *gDriver; /* vmbus driver object */
  53 static struct hv_device *gDevice; /* vmbus root device */
  54
  55 /*
  56  * VmbusGetChannelOffers - Retrieve the channel offers from the parent partition
  57  */
  58 static void VmbusGetChannelOffers(void)
  59 {
  60         vmbus_request_offers();
  61 }
  62
  63 /*
  64  * VmbusCreateChildDevice - Creates the child device on the bus that represents the channel offer
  65  */
  66 struct hv_device *VmbusChildDeviceCreate(struct hv_guid *DeviceType,
  67                                          struct hv_guid *DeviceInstance,
  68                                          struct vmbus_channel *channel)
  69 {
  70         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  71
  72         return vmbusDriver->OnChildDeviceCreate(DeviceType, DeviceInstance,
  73                                                 channel);
  74 }
  75
  76 /*
  77  * VmbusChildDeviceAdd - Registers the child device with the vmbus
  78  */
  79 int VmbusChildDeviceAdd(struct hv_device *ChildDevice)
  80 {
  81         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  82
  83         return vmbusDriver->OnChildDeviceAdd(gDevice, ChildDevice);
  84 }
  85
  86 /*
  87  * VmbusChildDeviceRemove Unregisters the child device from the vmbus
  88  */
  89 void VmbusChildDeviceRemove(struct hv_device *ChildDevice)
  90 {
  91         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  92
  93         vmbusDriver->OnChildDeviceRemove(ChildDevice);
  94 }
  95
  96 /*
  97  * VmbusOnDeviceAdd - Callback when the root bus device is added
  98  */
  99 static int VmbusOnDeviceAdd(struct hv_device *dev, void *AdditionalInfo)
 100 {
 101         u32 *irqvector = AdditionalInfo;
 102         int ret;
 103
 104         gDevice = dev;
 105
 106         memcpy(&gDevice->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
 107         memcpy(&gDevice->deviceInstance, &gVmbusDeviceId,
 108                sizeof(struct hv_guid));
 109
 110         /* strcpy(dev->name, "vmbus"); */
 111         /* SynIC setup... */
 112         on_each_cpu(HvSynicInit, (void *)irqvector, 1);
 113
 114         /* Connect to VMBus in the root partition */
 115         ret = VmbusConnect();
 116
 117         /* VmbusSendEvent(device->localPortId+1); */
 118         return ret;
 119 }
 120
 121 /*
 122  * VmbusOnDeviceRemove - Callback when the root bus device is removed
 123  */
 124 static int VmbusOnDeviceRemove(struct hv_device *dev)
 125 {
 126         int ret = 0;
 127
 128         vmbus_release_unattached_channels();
 129         VmbusDisconnect();
 130         on_each_cpu(HvSynicCleanup, NULL, 1);
 131         return ret;
 132 }
 133
 134 /*
 135  * VmbusOnCleanup - Perform any cleanup when the driver is removed
 136  */
 137 static void VmbusOnCleanup(struct hv_driver *drv)
 138 {
 139         /* struct vmbus_driver *driver = (struct vmbus_driver *)drv; */
 140
 141         HvCleanup();
 142 }
 143
 144 /*
 145  * VmbusOnMsgDPC - DPC routine to handle messages from the hypervisior
 146  */
 147 static void VmbusOnMsgDPC(struct hv_driver *drv)
 148 {
 149         int cpu = smp_processor_id();
 150         void *page_addr = gHvContext.synICMessagePage[cpu];
 151         struct hv_message *msg = (struct hv_message *)page_addr +
 152                                   VMBUS_MESSAGE_SINT;
 153         struct hv_message *copied;
 154
 155         while (1) {
 156                 if (msg->Header.MessageType == HvMessageTypeNone) {
 157                         /* no msg */
 158                         break;
 159                 } else {
 160                         copied = kmemdup(msg, sizeof(*copied), GFP_ATOMIC);
 161                         if (copied == NULL)
 162                                 continue;
 163
 164                         osd_schedule_callback(gVmbusConnection.WorkQueue,
 165                                               vmbus_onmessage,
 166                                               (void *)copied);
 167                 }
 168
 169                 msg->Header.MessageType = HvMessageTypeNone;
 170
 171                 /*
 172                  * Make sure the write to MessageType (ie set to
 173                  * HvMessageTypeNone) happens before we read the
 174                  * MessagePending and EOMing. Otherwise, the EOMing
 175                  * will not deliver any more messages since there is
 176                  * no empty slot
 177                  */
 178                 mb();
 179
 180                 if (msg->Header.MessageFlags.MessagePending) {
 181                         /*
 182                          * This will cause message queue rescan to
 183                          * possibly deliver another msg from the
 184                          * hypervisor
 185                          */
 186                         wrmsrl(HV_X64_MSR_EOM, 0);
 187                 }
 188         }
 189 }
 190
 191 /*
 192  * VmbusOnEventDPC - DPC routine to handle events from the hypervisior
 193  */
 194 static void VmbusOnEventDPC(struct hv_driver *drv)
 195 {
 196         /* TODO: Process any events */
 197         VmbusOnEvents();
 198 }
 199
 200 /*
 201  * VmbusOnISR - ISR routine
 202  */
 203 static int VmbusOnISR(struct hv_driver *drv)
 204 {
 205         int ret = 0;
 206         int cpu = smp_processor_id();
 207         void *page_addr;
 208         struct hv_message *msg;
 209         union hv_synic_event_flags *event;
 210
 211         page_addr = gHvContext.synICMessagePage[cpu];
 212         msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
 213
 214         /* Check if there are actual msgs to be process */
 215         if (msg->Header.MessageType != HvMessageTypeNone) {
 216                 DPRINT_DBG(VMBUS, "received msg type %d size %d",
 217                                 msg->Header.MessageType,
 218                                 msg->Header.PayloadSize);
 219                 ret |= 0x1;
 220         }
 221
 222         /* TODO: Check if there are events to be process */
 223         page_addr = gHvContext.synICEventPage[cpu];
 224         event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT;
 225
 226         /* Since we are a child, we only need to check bit 0 */
 227         if (test_and_clear_bit(0, (unsigned long *) &event->Flags32[0])) {
 228                 DPRINT_DBG(VMBUS, "received event %d", event->Flags32[0]);
 229                 ret |= 0x2;
 230         }
 231
 232         return ret;
 233 }
 234
 235 /*
 236  * VmbusInitialize - Main entry point
 237  */
 238 int VmbusInitialize(struct hv_driver *drv)
 239 {
 240         struct vmbus_driver *driver = (struct vmbus_driver *)drv;
 241         int ret;
 242
 243         DPRINT_INFO(VMBUS, "+++++++ HV Driver version = %s +++++++",
 244                     HV_DRV_VERSION);
 245         DPRINT_INFO(VMBUS, "+++++++ Vmbus supported version = %d +++++++",
 246                         VMBUS_REVISION_NUMBER);
 247         DPRINT_INFO(VMBUS, "+++++++ Vmbus using SINT %d +++++++",
 248                         VMBUS_MESSAGE_SINT);
 249         DPRINT_DBG(VMBUS, "sizeof(vmbus_channel_packet_page_buffer)=%zd, "
 250                         "sizeof(VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER)=%zd",
 251                         sizeof(struct vmbus_channel_packet_page_buffer),
 252                         sizeof(struct vmbus_channel_packet_multipage_buffer));
 253
 254         drv->name = gDriverName;
 255         memcpy(&drv->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
 256
 257         /* Setup dispatch table */
 258         driver->Base.OnDeviceAdd        = VmbusOnDeviceAdd;
 259         driver->Base.OnDeviceRemove     = VmbusOnDeviceRemove;
 260         driver->Base.OnCleanup          = VmbusOnCleanup;
 261         driver->OnIsr                   = VmbusOnISR;
 262         driver->OnMsgDpc                = VmbusOnMsgDPC;
 263         driver->OnEventDpc              = VmbusOnEventDPC;
 264         driver->GetChannelOffers        = VmbusGetChannelOffers;
 265
 266         /* Hypervisor initialization...setup hypercall page..etc */
 267         ret = HvInit();
 268         if (ret != 0)
 269                 DPRINT_ERR(VMBUS, "Unable to initialize the hypervisor - 0x%x",
 270                                 ret);
 271         gDriver = drv;
 272
 273         return ret;
 274 }