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         DPRINT_ENTER(VMBUS);
  61         VmbusChannelRequestOffers();
  62         DPRINT_EXIT(VMBUS);
  63 }
  64
  65 /*
  66  * VmbusGetChannelInterface - Get the channel interface
  67  */
  68 static void VmbusGetChannelInterface(struct vmbus_channel_interface *Interface)
  69 {
  70         GetChannelInterface(Interface);
  71 }
  72
  73 /*
  74  * VmbusGetChannelInfo - Get the device info for the specified device object
  75  */
  76 static void VmbusGetChannelInfo(struct hv_device *DeviceObject,
  77                                 struct hv_device_info *DeviceInfo)
  78 {
  79         GetChannelInfo(DeviceObject, DeviceInfo);
  80 }
  81
  82 /*
  83  * VmbusCreateChildDevice - Creates the child device on the bus that represents the channel offer
  84  */
  85 struct hv_device *VmbusChildDeviceCreate(struct hv_guid *DeviceType,
  86                                          struct hv_guid *DeviceInstance,
  87                                          void *Context)
  88 {
  89         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  90
  91         return vmbusDriver->OnChildDeviceCreate(DeviceType, DeviceInstance,
  92                                                 Context);
  93 }
  94
  95 /*
  96  * VmbusChildDeviceAdd - Registers the child device with the vmbus
  97  */
  98 int VmbusChildDeviceAdd(struct hv_device *ChildDevice)
  99 {
 100         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
 101
 102         return vmbusDriver->OnChildDeviceAdd(gDevice, ChildDevice);
 103 }
 104
 105 /*
 106  * VmbusChildDeviceRemove Unregisters the child device from the vmbus
 107  */
 108 void VmbusChildDeviceRemove(struct hv_device *ChildDevice)
 109 {
 110         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
 111
 112         vmbusDriver->OnChildDeviceRemove(ChildDevice);
 113 }
 114
 115 /*
 116  * VmbusOnDeviceAdd - Callback when the root bus device is added
 117  */
 118 static int VmbusOnDeviceAdd(struct hv_device *dev, void *AdditionalInfo)
 119 {
 120         u32 *irqvector = AdditionalInfo;
 121         int ret;
 122
 123         DPRINT_ENTER(VMBUS);
 124
 125         gDevice = dev;
 126
 127         memcpy(&gDevice->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
 128         memcpy(&gDevice->deviceInstance, &gVmbusDeviceId,
 129                sizeof(struct hv_guid));
 130
 131         /* strcpy(dev->name, "vmbus"); */
 132         /* SynIC setup... */
 133         on_each_cpu(HvSynicInit, (void *)irqvector, 1);
 134
 135         /* Connect to VMBus in the root partition */
 136         ret = VmbusConnect();
 137
 138         /* VmbusSendEvent(device->localPortId+1); */
 139         DPRINT_EXIT(VMBUS);
 140
 141         return ret;
 142 }
 143
 144 /*
 145  * VmbusOnDeviceRemove - Callback when the root bus device is removed
 146  */
 147 static int VmbusOnDeviceRemove(struct hv_device *dev)
 148 {
 149         int ret = 0;
 150
 151         DPRINT_ENTER(VMBUS);
 152         VmbusChannelReleaseUnattachedChannels();
 153         VmbusDisconnect();
 154         on_each_cpu(HvSynicCleanup, NULL, 1);
 155         DPRINT_EXIT(VMBUS);
 156
 157         return ret;
 158 }
 159
 160 /*
 161  * VmbusOnCleanup - Perform any cleanup when the driver is removed
 162  */
 163 static void VmbusOnCleanup(struct hv_driver *drv)
 164 {
 165         /* struct vmbus_driver *driver = (struct vmbus_driver *)drv; */
 166
 167         DPRINT_ENTER(VMBUS);
 168         HvCleanup();
 169         DPRINT_EXIT(VMBUS);
 170 }
 171
 172 /*
 173  * VmbusOnMsgDPC - DPC routine to handle messages from the hypervisior
 174  */
 175 static void VmbusOnMsgDPC(struct hv_driver *drv)
 176 {
 177         int cpu = smp_processor_id();
 178         void *page_addr = gHvContext.synICMessagePage[cpu];
 179         struct hv_message *msg = (struct hv_message *)page_addr +
 180                                   VMBUS_MESSAGE_SINT;
 181         struct hv_message *copied;
 182
 183         while (1) {
 184                 if (msg->Header.MessageType == HvMessageTypeNone) {
 185                         /* no msg */
 186                         break;
 187                 } else {
 188                         copied = kmalloc(sizeof(*copied), GFP_ATOMIC);
 189                         if (copied == NULL)
 190                                 continue;
 191
 192                         memcpy(copied, msg, sizeof(*copied));
 193                         osd_schedule_callback(gVmbusConnection.WorkQueue,
 194                                               VmbusOnChannelMessage,
 195                                               (void *)copied);
 196                 }
 197
 198                 msg->Header.MessageType = HvMessageTypeNone;
 199
 200                 /*
 201                  * Make sure the write to MessageType (ie set to
 202                  * HvMessageTypeNone) happens before we read the
 203                  * MessagePending and EOMing. Otherwise, the EOMing
 204                  * will not deliver any more messages since there is
 205                  * no empty slot
 206                  */
 207                 mb();
 208
 209                 if (msg->Header.MessageFlags.MessagePending) {
 210                         /*
 211                          * This will cause message queue rescan to
 212                          * possibly deliver another msg from the
 213                          * hypervisor
 214                          */
 215                         wrmsrl(HV_X64_MSR_EOM, 0);
 216                 }
 217         }
 218 }
 219
 220 /*
 221  * VmbusOnEventDPC - DPC routine to handle events from the hypervisior
 222  */
 223 static void VmbusOnEventDPC(struct hv_driver *drv)
 224 {
 225         /* TODO: Process any events */
 226         VmbusOnEvents();
 227 }
 228
 229 /*
 230  * VmbusOnISR - ISR routine
 231  */
 232 static int VmbusOnISR(struct hv_driver *drv)
 233 {
 234         int ret = 0;
 235         int cpu = smp_processor_id();
 236         void *page_addr;
 237         struct hv_message *msg;
 238         union hv_synic_event_flags *event;
 239
 240         page_addr = gHvContext.synICMessagePage[cpu];
 241         msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
 242
 243         DPRINT_ENTER(VMBUS);
 244
 245         /* Check if there are actual msgs to be process */
 246         if (msg->Header.MessageType != HvMessageTypeNone) {
 247                 DPRINT_DBG(VMBUS, "received msg type %d size %d",
 248                                 msg->Header.MessageType,
 249                                 msg->Header.PayloadSize);
 250                 ret |= 0x1;
 251         }
 252
 253         /* TODO: Check if there are events to be process */
 254         page_addr = gHvContext.synICEventPage[cpu];
 255         event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT;
 256
 257         /* Since we are a child, we only need to check bit 0 */
 258         if (test_and_clear_bit(0, (unsigned long *) &event->Flags32[0])) {
 259                 DPRINT_DBG(VMBUS, "received event %d", event->Flags32[0]);
 260                 ret |= 0x2;
 261         }
 262
 263         DPRINT_EXIT(VMBUS);
 264         return ret;
 265 }
 266
 267 /*
 268  * VmbusInitialize - Main entry point
 269  */
 270 int VmbusInitialize(struct hv_driver *drv)
 271 {
 272         struct vmbus_driver *driver = (struct vmbus_driver *)drv;
 273         int ret;
 274
 275         DPRINT_ENTER(VMBUS);
 276
 277         DPRINT_INFO(VMBUS, "+++++++ HV Driver version = %s +++++++",
 278                     HV_DRV_VERSION);
 279         DPRINT_INFO(VMBUS, "+++++++ Vmbus supported version = %d +++++++",
 280                         VMBUS_REVISION_NUMBER);
 281         DPRINT_INFO(VMBUS, "+++++++ Vmbus using SINT %d +++++++",
 282                         VMBUS_MESSAGE_SINT);
 283         DPRINT_DBG(VMBUS, "sizeof(VMBUS_CHANNEL_PACKET_PAGE_BUFFER)=%zd, "
 284                         "sizeof(VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER)=%zd",
 285                         sizeof(struct VMBUS_CHANNEL_PACKET_PAGE_BUFFER),
 286                         sizeof(struct VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER));
 287
 288         drv->name = gDriverName;
 289         memcpy(&drv->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
 290
 291         /* Setup dispatch table */
 292         driver->Base.OnDeviceAdd        = VmbusOnDeviceAdd;
 293         driver->Base.OnDeviceRemove     = VmbusOnDeviceRemove;
 294         driver->Base.OnCleanup          = VmbusOnCleanup;
 295         driver->OnIsr                   = VmbusOnISR;
 296         driver->OnMsgDpc                = VmbusOnMsgDPC;
 297         driver->OnEventDpc              = VmbusOnEventDPC;
 298         driver->GetChannelOffers        = VmbusGetChannelOffers;
 299         driver->GetChannelInterface     = VmbusGetChannelInterface;
 300         driver->GetChannelInfo          = VmbusGetChannelInfo;
 301
 302         /* Hypervisor initialization...setup hypercall page..etc */
 303         ret = HvInit();
 304         if (ret != 0)
 305                 DPRINT_ERR(VMBUS, "Unable to initialize the hypervisor - 0x%x",
 306                                 ret);
 307         gDriver = drv;
 308
 309         DPRINT_EXIT(VMBUS);
 310
 311         return ret;
 312 }