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