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  * VmbusChildDeviceAdd - Registers the child device with the vmbus
  57  */
  58 int VmbusChildDeviceAdd(struct hv_device *ChildDevice)
  59 {
  60         struct vmbus_driver *vmbusDriver = (struct vmbus_driver *)gDriver;
  61
  62         return vmbusDriver->OnChildDeviceAdd(gDevice, ChildDevice);
  63 }
  64
  65 /*
  66  * VmbusOnDeviceAdd - Callback when the root bus device is added
  67  */
  68 static int VmbusOnDeviceAdd(struct hv_device *dev, void *AdditionalInfo)
  69 {
  70         u32 *irqvector = AdditionalInfo;
  71         int ret;
  72
  73         gDevice = dev;
  74
  75         memcpy(&gDevice->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
  76         memcpy(&gDevice->deviceInstance, &gVmbusDeviceId,
  77                sizeof(struct hv_guid));
  78
  79         /* strcpy(dev->name, "vmbus"); */
  80         /* SynIC setup... */
  81         on_each_cpu(hv_synic_init, (void *)irqvector, 1);
  82
  83         /* Connect to VMBus in the root partition */
  84         ret = VmbusConnect();
  85
  86         /* VmbusSendEvent(device->localPortId+1); */
  87         return ret;
  88 }
  89
  90 /*
  91  * VmbusOnDeviceRemove - Callback when the root bus device is removed
  92  */
  93 static int VmbusOnDeviceRemove(struct hv_device *dev)
  94 {
  95         int ret = 0;
  96
  97         vmbus_release_unattached_channels();
  98         VmbusDisconnect();
  99         on_each_cpu(hv_synic_cleanup, NULL, 1);
 100         return ret;
 101 }
 102
 103 /*
 104  * VmbusOnCleanup - Perform any cleanup when the driver is removed
 105  */
 106 static void VmbusOnCleanup(struct hv_driver *drv)
 107 {
 108         /* struct vmbus_driver *driver = (struct vmbus_driver *)drv; */
 109
 110         hv_cleanup();
 111 }
 112
 113 /*
 114  * vmbus_on_msg_dpc - DPC routine to handle messages from the hypervisior
 115  */
 116 void vmbus_on_msg_dpc(struct hv_driver *drv)
 117 {
 118         int cpu = smp_processor_id();
 119         void *page_addr = hv_context.synic_message_page[cpu];
 120         struct hv_message *msg = (struct hv_message *)page_addr +
 121                                   VMBUS_MESSAGE_SINT;
 122         struct hv_message *copied;
 123
 124         while (1) {
 125                 if (msg->header.message_type == HVMSG_NONE) {
 126                         /* no msg */
 127                         break;
 128                 } else {
 129                         copied = kmemdup(msg, sizeof(*copied), GFP_ATOMIC);
 130                         if (copied == NULL)
 131                                 continue;
 132
 133                         osd_schedule_callback(gVmbusConnection.WorkQueue,
 134                                               vmbus_onmessage,
 135                                               (void *)copied);
 136                 }
 137
 138                 msg->header.message_type = HVMSG_NONE;
 139
 140                 /*
 141                  * Make sure the write to MessageType (ie set to
 142                  * HVMSG_NONE) happens before we read the
 143                  * MessagePending and EOMing. Otherwise, the EOMing
 144                  * will not deliver any more messages since there is
 145                  * no empty slot
 146                  */
 147                 mb();
 148
 149                 if (msg->header.message_flags.msg_pending) {
 150                         /*
 151                          * This will cause message queue rescan to
 152                          * possibly deliver another msg from the
 153                          * hypervisor
 154                          */
 155                         wrmsrl(HV_X64_MSR_EOM, 0);
 156                 }
 157         }
 158 }
 159
 160 /*
 161  * vmbus_on_event_dpc - DPC routine to handle events from the hypervisior
 162  */
 163 void vmbus_on_event_dpc(struct hv_driver *drv)
 164 {
 165         /* TODO: Process any events */
 166         VmbusOnEvents();
 167 }
 168
 169 /*
 170  * vmbus_on_isr - ISR routine
 171  */
 172 int vmbus_on_isr(struct hv_driver *drv)
 173 {
 174         int ret = 0;
 175         int cpu = smp_processor_id();
 176         void *page_addr;
 177         struct hv_message *msg;
 178         union hv_synic_event_flags *event;
 179
 180         page_addr = hv_context.synic_message_page[cpu];
 181         msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
 182
 183         /* Check if there are actual msgs to be process */
 184         if (msg->header.message_type != HVMSG_NONE) {
 185                 DPRINT_DBG(VMBUS, "received msg type %d size %d",
 186                                 msg->header.message_type,
 187                                 msg->header.payload_size);
 188                 ret |= 0x1;
 189         }
 190
 191         /* TODO: Check if there are events to be process */
 192         page_addr = hv_context.synic_event_page[cpu];
 193         event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT;
 194
 195         /* Since we are a child, we only need to check bit 0 */
 196         if (test_and_clear_bit(0, (unsigned long *) &event->flags32[0])) {
 197                 DPRINT_DBG(VMBUS, "received event %d", event->flags32[0]);
 198                 ret |= 0x2;
 199         }
 200
 201         return ret;
 202 }
 203
 204 /*
 205  * VmbusInitialize - Main entry point
 206  */
 207 int VmbusInitialize(struct hv_driver *drv)
 208 {
 209         struct vmbus_driver *driver = (struct vmbus_driver *)drv;
 210         int ret;
 211
 212         DPRINT_INFO(VMBUS, "+++++++ HV Driver version = %s +++++++",
 213                     HV_DRV_VERSION);
 214         DPRINT_INFO(VMBUS, "+++++++ Vmbus supported version = %d +++++++",
 215                         VMBUS_REVISION_NUMBER);
 216         DPRINT_INFO(VMBUS, "+++++++ Vmbus using SINT %d +++++++",
 217                         VMBUS_MESSAGE_SINT);
 218         DPRINT_DBG(VMBUS, "sizeof(vmbus_channel_packet_page_buffer)=%zd, "
 219                         "sizeof(VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER)=%zd",
 220                         sizeof(struct vmbus_channel_packet_page_buffer),
 221                         sizeof(struct vmbus_channel_packet_multipage_buffer));
 222
 223         drv->name = gDriverName;
 224         memcpy(&drv->deviceType, &gVmbusDeviceType, sizeof(struct hv_guid));
 225
 226         /* Setup dispatch table */
 227         driver->Base.OnDeviceAdd        = VmbusOnDeviceAdd;
 228         driver->Base.OnDeviceRemove     = VmbusOnDeviceRemove;
 229         driver->Base.OnCleanup          = VmbusOnCleanup;
 230
 231         /* Hypervisor initialization...setup hypercall page..etc */
 232         ret = hv_init();
 233         if (ret != 0)
 234                 DPRINT_ERR(VMBUS, "Unable to initialize the hypervisor - 0x%x",
 235                                 ret);
 236         gDriver = drv;
 237
 238         return ret;
 239 }