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