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  * VmbusChildDeviceAdd - Registers the child device with the vmbus
  65  */
  66 int VmbusChildDeviceAdd(struct hv_device *ChildDevice)
  67 {
  68         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  69
  70         return vmbusDriver->OnChildDeviceAdd(gDevice, ChildDevice);
  71 }
  72
  73 /*
  74  * VmbusChildDeviceRemove Unregisters the child device from the vmbus
  75  */
  76 void VmbusChildDeviceRemove(struct hv_device *ChildDevice)
  77 {
  78         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  79
  80         vmbusDriver->OnChildDeviceRemove(ChildDevice);
  81 }
  82
  83 /*
  84  * VmbusOnDeviceAdd - Callback when the root bus device is added
  85  */
  86 static int VmbusOnDeviceAdd(struct hv_device *dev, void *AdditionalInfo)
  87 {
  88         u32 *irqvector = AdditionalInfo;
  89         int ret;
  90
  91         gDevice = dev;
  92
  93         memcpy(&gDevice->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
  94         memcpy(&gDevice->deviceInstance, &gVmbusDeviceId,
  95                sizeof(struct hv_guid));
  96
  97         /* strcpy(dev->name, "vmbus"); */
  98         /* SynIC setup... */
  99         on_each_cpu(hv_synic_init, (void *)irqvector, 1);
 100
 101         /* Connect to VMBus in the root partition */
 102         ret = VmbusConnect();
 103
 104         /* VmbusSendEvent(device->localPortId+1); */
 105         return ret;
 106 }
 107
 108 /*
 109  * VmbusOnDeviceRemove - Callback when the root bus device is removed
 110  */
 111 static int VmbusOnDeviceRemove(struct hv_device *dev)
 112 {
 113         int ret = 0;
 114
 115         vmbus_release_unattached_channels();
 116         VmbusDisconnect();
 117         on_each_cpu(hv_synic_cleanup, NULL, 1);
 118         return ret;
 119 }
 120
 121 /*
 122  * VmbusOnCleanup - Perform any cleanup when the driver is removed
 123  */
 124 static void VmbusOnCleanup(struct hv_driver *drv)
 125 {
 126         /* struct vmbus_driver *driver = (struct vmbus_driver *)drv; */
 127
 128         hv_cleanup();
 129 }
 130
 131 /*
 132  * VmbusOnMsgDPC - DPC routine to handle messages from the hypervisior
 133  */
 134 static void VmbusOnMsgDPC(struct hv_driver *drv)
 135 {
 136         int cpu = smp_processor_id();
 137         void *page_addr = hv_context.synic_message_page[cpu];
 138         struct hv_message *msg = (struct hv_message *)page_addr +
 139                                   VMBUS_MESSAGE_SINT;
 140         struct hv_message *copied;
 141
 142         while (1) {
 143                 if (msg->header.message_type == HVMSG_NONE) {
 144                         /* no msg */
 145                         break;
 146                 } else {
 147                         copied = kmemdup(msg, sizeof(*copied), GFP_ATOMIC);
 148                         if (copied == NULL)
 149                                 continue;
 150
 151                         osd_schedule_callback(gVmbusConnection.WorkQueue,
 152                                               vmbus_onmessage,
 153                                               (void *)copied);
 154                 }
 155
 156                 msg->header.message_type = HVMSG_NONE;
 157
 158                 /*
 159                  * Make sure the write to MessageType (ie set to
 160                  * HVMSG_NONE) happens before we read the
 161                  * MessagePending and EOMing. Otherwise, the EOMing
 162                  * will not deliver any more messages since there is
 163                  * no empty slot
 164                  */
 165                 mb();
 166
 167                 if (msg->header.message_flags.msg_pending) {
 168                         /*
 169                          * This will cause message queue rescan to
 170                          * possibly deliver another msg from the
 171                          * hypervisor
 172                          */
 173                         wrmsrl(HV_X64_MSR_EOM, 0);
 174                 }
 175         }
 176 }
 177
 178 /*
 179  * VmbusOnEventDPC - DPC routine to handle events from the hypervisior
 180  */
 181 static void VmbusOnEventDPC(struct hv_driver *drv)
 182 {
 183         /* TODO: Process any events */
 184         VmbusOnEvents();
 185 }
 186
 187 /*
 188  * VmbusOnISR - ISR routine
 189  */
 190 static int VmbusOnISR(struct hv_driver *drv)
 191 {
 192         int ret = 0;
 193         int cpu = smp_processor_id();
 194         void *page_addr;
 195         struct hv_message *msg;
 196         union hv_synic_event_flags *event;
 197
 198         page_addr = hv_context.synic_message_page[cpu];
 199         msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
 200
 201         /* Check if there are actual msgs to be process */
 202         if (msg->header.message_type != HVMSG_NONE) {
 203                 DPRINT_DBG(VMBUS, "received msg type %d size %d",
 204                                 msg->header.message_type,
 205                                 msg->header.payload_size);
 206                 ret |= 0x1;
 207         }
 208
 209         /* TODO: Check if there are events to be process */
 210         page_addr = hv_context.synic_event_page[cpu];
 211         event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT;
 212
 213         /* Since we are a child, we only need to check bit 0 */
 214         if (test_and_clear_bit(0, (unsigned long *) &event->flags32[0])) {
 215                 DPRINT_DBG(VMBUS, "received event %d", event->flags32[0]);
 216                 ret |= 0x2;
 217         }
 218
 219         return ret;
 220 }
 221
 222 /*
 223  * VmbusInitialize - Main entry point
 224  */
 225 int VmbusInitialize(struct hv_driver *drv)
 226 {
 227         struct vmbus_driver *driver = (struct vmbus_driver *)drv;
 228         int ret;
 229
 230         DPRINT_INFO(VMBUS, "+++++++ HV Driver version = %s +++++++",
 231                     HV_DRV_VERSION);
 232         DPRINT_INFO(VMBUS, "+++++++ Vmbus supported version = %d +++++++",
 233                         VMBUS_REVISION_NUMBER);
 234         DPRINT_INFO(VMBUS, "+++++++ Vmbus using SINT %d +++++++",
 235                         VMBUS_MESSAGE_SINT);
 236         DPRINT_DBG(VMBUS, "sizeof(vmbus_channel_packet_page_buffer)=%zd, "
 237                         "sizeof(VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER)=%zd",
 238                         sizeof(struct vmbus_channel_packet_page_buffer),
 239                         sizeof(struct vmbus_channel_packet_multipage_buffer));
 240
 241         drv->name = gDriverName;
 242         memcpy(&drv->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
 243
 244         /* Setup dispatch table */
 245         driver->Base.OnDeviceAdd        = VmbusOnDeviceAdd;
 246         driver->Base.OnDeviceRemove     = VmbusOnDeviceRemove;
 247         driver->Base.OnCleanup          = VmbusOnCleanup;
 248         driver->OnIsr                   = VmbusOnISR;
 249         driver->OnMsgDpc                = VmbusOnMsgDPC;
 250         driver->OnEventDpc              = VmbusOnEventDPC;
 251         driver->GetChannelOffers        = VmbusGetChannelOffers;
 252
 253         /* Hypervisor initialization...setup hypercall page..etc */
 254         ret = hv_init();
 255         if (ret != 0)
 256                 DPRINT_ERR(VMBUS, "Unable to initialize the hypervisor - 0x%x",
 257                                 ret);
 258         gDriver = drv;
 259
 260         return ret;
 261 }