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