drivers/staging/hv/hv.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 <linux/vmalloc.h>
  26 #include "osd.h"
  27 #include "logging.h"
  28 #include "vmbus_private.h"
  29
  30 /* The one and only */
  31 struct hv_context gHvContext = {
  32         .SynICInitialized       = false,
  33         .HypercallPage          = NULL,
  34         .SignalEventParam       = NULL,
  35         .SignalEventBuffer      = NULL,
  36 };
  37
  38 /*
  39  * HvQueryHypervisorPresence - Query the cpuid for presense of windows hypervisor
  40  */
  41 static int HvQueryHypervisorPresence(void)
  42 {
  43         unsigned int eax;
  44         unsigned int ebx;
  45         unsigned int ecx;
  46         unsigned int edx;
  47         unsigned int op;
  48
  49         eax = 0;
  50         ebx = 0;
  51         ecx = 0;
  52         edx = 0;
  53         op = HVCPUID_VERSION_FEATURES;
  54         cpuid(op, &eax, &ebx, &ecx, &edx);
  55
  56         return ecx & HV_PRESENT_BIT;
  57 }
  58
  59 /*
  60  * HvQueryHypervisorInfo - Get version info of the windows hypervisor
  61  */
  62 static int HvQueryHypervisorInfo(void)
  63 {
  64         unsigned int eax;
  65         unsigned int ebx;
  66         unsigned int ecx;
  67         unsigned int edx;
  68         unsigned int maxLeaf;
  69         unsigned int op;
  70
  71         /*
  72         * Its assumed that this is called after confirming that Viridian
  73         * is present. Query id and revision.
  74         */
  75         eax = 0;
  76         ebx = 0;
  77         ecx = 0;
  78         edx = 0;
  79         op = HVCPUID_VENDOR_MAXFUNCTION;
  80         cpuid(op, &eax, &ebx, &ecx, &edx);
  81
  82         DPRINT_INFO(VMBUS, "Vendor ID: %c%c%c%c%c%c%c%c%c%c%c%c",
  83                     (ebx & 0xFF),
  84                     ((ebx >> 8) & 0xFF),
  85                     ((ebx >> 16) & 0xFF),
  86                     ((ebx >> 24) & 0xFF),
  87                     (ecx & 0xFF),
  88                     ((ecx >> 8) & 0xFF),
  89                     ((ecx >> 16) & 0xFF),
  90                     ((ecx >> 24) & 0xFF),
  91                     (edx & 0xFF),
  92                     ((edx >> 8) & 0xFF),
  93                     ((edx >> 16) & 0xFF),
  94                     ((edx >> 24) & 0xFF));
  95
  96         maxLeaf = eax;
  97         eax = 0;
  98         ebx = 0;
  99         ecx = 0;
 100         edx = 0;
 101         op = HVCPUID_INTERFACE;
 102         cpuid(op, &eax, &ebx, &ecx, &edx);
 103
 104         DPRINT_INFO(VMBUS, "Interface ID: %c%c%c%c",
 105                     (eax & 0xFF),
 106                     ((eax >> 8) & 0xFF),
 107                     ((eax >> 16) & 0xFF),
 108                     ((eax >> 24) & 0xFF));
 109
 110         if (maxLeaf >= HVCPUID_VERSION) {
 111                 eax = 0;
 112                 ebx = 0;
 113                 ecx = 0;
 114                 edx = 0;
 115                 op = HVCPUID_VERSION;
 116                 cpuid(op, &eax, &ebx, &ecx, &edx);
 117                 DPRINT_INFO(VMBUS, "OS Build:%d-%d.%d-%d-%d.%d",\
 118                             eax,
 119                             ebx >> 16,
 120                             ebx & 0xFFFF,
 121                             ecx,
 122                             edx >> 24,
 123                             edx & 0xFFFFFF);
 124         }
 125         return maxLeaf;
 126 }
 127
 128 /*
 129  * HvDoHypercall - Invoke the specified hypercall
 130  */
 131 static u64 HvDoHypercall(u64 Control, void *Input, void *Output)
 132 {
 133 #ifdef CONFIG_X86_64
 134         u64 hvStatus = 0;
 135         u64 inputAddress = (Input) ? virt_to_phys(Input) : 0;
 136         u64 outputAddress = (Output) ? virt_to_phys(Output) : 0;
 137         volatile void *hypercallPage = gHvContext.HypercallPage;
 138
 139         DPRINT_DBG(VMBUS, "Hypercall <control %llx input phys %llx virt %p "
 140                    "output phys %llx virt %p hypercall %p>",
 141                    Control, inputAddress, Input,
 142                    outputAddress, Output, hypercallPage);
 143
 144         __asm__ __volatile__("mov %0, %%r8" : : "r" (outputAddress) : "r8");
 145         __asm__ __volatile__("call *%3" : "=a" (hvStatus) :
 146                              "c" (Control), "d" (inputAddress),
 147                              "m" (hypercallPage));
 148
 149         DPRINT_DBG(VMBUS, "Hypercall <return %llx>",  hvStatus);
 150
 151         return hvStatus;
 152
 153 #else
 154
 155         u32 controlHi = Control >> 32;
 156         u32 controlLo = Control & 0xFFFFFFFF;
 157         u32 hvStatusHi = 1;
 158         u32 hvStatusLo = 1;
 159         u64 inputAddress = (Input) ? virt_to_phys(Input) : 0;
 160         u32 inputAddressHi = inputAddress >> 32;
 161         u32 inputAddressLo = inputAddress & 0xFFFFFFFF;
 162         u64 outputAddress = (Output) ? virt_to_phys(Output) : 0;
 163         u32 outputAddressHi = outputAddress >> 32;
 164         u32 outputAddressLo = outputAddress & 0xFFFFFFFF;
 165         volatile void *hypercallPage = gHvContext.HypercallPage;
 166
 167         DPRINT_DBG(VMBUS, "Hypercall <control %llx input %p output %p>",
 168                    Control, Input, Output);
 169
 170         __asm__ __volatile__ ("call *%8" : "=d"(hvStatusHi),
 171                               "=a"(hvStatusLo) : "d" (controlHi),
 172                               "a" (controlLo), "b" (inputAddressHi),
 173                               "c" (inputAddressLo), "D"(outputAddressHi),
 174                               "S"(outputAddressLo), "m" (hypercallPage));
 175
 176         DPRINT_DBG(VMBUS, "Hypercall <return %llx>",
 177                    hvStatusLo | ((u64)hvStatusHi << 32));
 178
 179         return hvStatusLo | ((u64)hvStatusHi << 32);
 180 #endif /* !x86_64 */
 181 }
 182
 183 /*
 184  * HvInit - Main initialization routine.
 185  *
 186  * This routine must be called before any other routines in here are called
 187  */
 188 int HvInit(void)
 189 {
 190         int ret = 0;
 191         int maxLeaf;
 192         union hv_x64_msr_hypercall_contents hypercallMsr;
 193         void *virtAddr = NULL;
 194
 195         memset(gHvContext.synICEventPage, 0, sizeof(void *) * MAX_NUM_CPUS);
 196         memset(gHvContext.synICMessagePage, 0, sizeof(void *) * MAX_NUM_CPUS);
 197
 198         if (!HvQueryHypervisorPresence()) {
 199                 DPRINT_ERR(VMBUS, "No Windows hypervisor detected!!");
 200                 goto Cleanup;
 201         }
 202
 203         DPRINT_INFO(VMBUS,
 204                     "Windows hypervisor detected! Retrieving more info...");
 205
 206         maxLeaf = HvQueryHypervisorInfo();
 207         /* HvQueryHypervisorFeatures(maxLeaf); */
 208
 209         /*
 210          * We only support running on top of Hyper-V
 211          */
 212         rdmsrl(HV_X64_MSR_GUEST_OS_ID, gHvContext.GuestId);
 213
 214         if (gHvContext.GuestId != 0) {
 215                 DPRINT_ERR(VMBUS, "Unknown guest id (0x%llx)!!",
 216                                 gHvContext.GuestId);
 217                 goto Cleanup;
 218         }
 219
 220         /* Write our OS info */
 221         wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID);
 222         gHvContext.GuestId = HV_LINUX_GUEST_ID;
 223
 224         /* See if the hypercall page is already set */
 225         rdmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 226
 227         /*
 228         * Allocate the hypercall page memory
 229         * virtAddr = osd_PageAlloc(1);
 230         */
 231         virtAddr = osd_VirtualAllocExec(PAGE_SIZE);
 232
 233         if (!virtAddr) {
 234                 DPRINT_ERR(VMBUS,
 235                            "unable to allocate hypercall page!!");
 236                 goto Cleanup;
 237         }
 238
 239         hypercallMsr.enable = 1;
 240
 241         hypercallMsr.guest_physical_address = vmalloc_to_pfn(virtAddr);
 242         wrmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 243
 244         /* Confirm that hypercall page did get setup. */
 245         hypercallMsr.as_uint64 = 0;
 246         rdmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 247
 248         if (!hypercallMsr.enable) {
 249                 DPRINT_ERR(VMBUS, "unable to set hypercall page!!");
 250                 goto Cleanup;
 251         }
 252
 253         gHvContext.HypercallPage = virtAddr;
 254
 255         DPRINT_INFO(VMBUS, "Hypercall page VA=%p, PA=0x%0llx",
 256                     gHvContext.HypercallPage,
 257                     (u64)hypercallMsr.guest_physical_address << PAGE_SHIFT);
 258
 259         /* Setup the global signal event param for the signal event hypercall */
 260         gHvContext.SignalEventBuffer =
 261                         kmalloc(sizeof(struct hv_input_signal_event_buffer),
 262                                 GFP_KERNEL);
 263         if (!gHvContext.SignalEventBuffer)
 264                 goto Cleanup;
 265
 266         gHvContext.SignalEventParam =
 267                 (struct hv_input_signal_event *)
 268                         (ALIGN_UP((unsigned long)gHvContext.SignalEventBuffer,
 269                                   HV_HYPERCALL_PARAM_ALIGN));
 270         gHvContext.SignalEventParam->connectionid.asu32 = 0;
 271         gHvContext.SignalEventParam->connectionid.u.id =
 272                                                 VMBUS_EVENT_CONNECTION_ID;
 273         gHvContext.SignalEventParam->flag_number = 0;
 274         gHvContext.SignalEventParam->rsvdz = 0;
 275
 276         return ret;
 277
 278 Cleanup:
 279         if (virtAddr) {
 280                 if (hypercallMsr.enable) {
 281                         hypercallMsr.as_uint64 = 0;
 282                         wrmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 283                 }
 284
 285                 vfree(virtAddr);
 286         }
 287         ret = -1;
 288         return ret;
 289 }
 290
 291 /*
 292  * HvCleanup - Cleanup routine.
 293  *
 294  * This routine is called normally during driver unloading or exiting.
 295  */
 296 void HvCleanup(void)
 297 {
 298         union hv_x64_msr_hypercall_contents hypercallMsr;
 299
 300         kfree(gHvContext.SignalEventBuffer);
 301         gHvContext.SignalEventBuffer = NULL;
 302         gHvContext.SignalEventParam = NULL;
 303
 304         if (gHvContext.HypercallPage) {
 305                 hypercallMsr.as_uint64 = 0;
 306                 wrmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 307                 vfree(gHvContext.HypercallPage);
 308                 gHvContext.HypercallPage = NULL;
 309         }
 310 }
 311
 312 /*
 313  * HvPostMessage - Post a message using the hypervisor message IPC.
 314  *
 315  * This involves a hypercall.
 316  */
 317 u16 HvPostMessage(union hv_connection_id connectionId,
 318                   enum hv_message_type messageType,
 319                   void *payload, size_t payloadSize)
 320 {
 321         struct alignedInput {
 322                 u64 alignment8;
 323                 struct hv_input_post_message msg;
 324         };
 325
 326         struct hv_input_post_message *alignedMsg;
 327         u16 status;
 328         unsigned long addr;
 329
 330         if (payloadSize > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
 331                 return -1;
 332
 333         addr = (unsigned long)kmalloc(sizeof(struct alignedInput), GFP_ATOMIC);
 334         if (!addr)
 335                 return -1;
 336
 337         alignedMsg = (struct hv_input_post_message *)
 338                         (ALIGN_UP(addr, HV_HYPERCALL_PARAM_ALIGN));
 339
 340         alignedMsg->connectionid = connectionId;
 341         alignedMsg->message_type = messageType;
 342         alignedMsg->payload_size = payloadSize;
 343         memcpy((void *)alignedMsg->payload, payload, payloadSize);
 344
 345         status = HvDoHypercall(HVCALL_POST_MESSAGE, alignedMsg, NULL) & 0xFFFF;
 346
 347         kfree((void *)addr);
 348
 349         return status;
 350 }
 351
 352
 353 /*
 354  * HvSignalEvent - Signal an event on the specified connection using the hypervisor event IPC.
 355  *
 356  * This involves a hypercall.
 357  */
 358 u16 HvSignalEvent(void)
 359 {
 360         u16 status;
 361
 362         status = HvDoHypercall(HVCALL_SIGNAL_EVENT, gHvContext.SignalEventParam,
 363                                NULL) & 0xFFFF;
 364         return status;
 365 }
 366
 367 /*
 368  * HvSynicInit - Initialize the Synthethic Interrupt Controller.
 369  *
 370  * If it is already initialized by another entity (ie x2v shim), we need to
 371  * retrieve the initialized message and event pages.  Otherwise, we create and
 372  * initialize the message and event pages.
 373  */
 374 void HvSynicInit(void *irqarg)
 375 {
 376         u64 version;
 377         union hv_synic_simp simp;
 378         union hv_synic_siefp siefp;
 379         union hv_synic_sint sharedSint;
 380         union hv_synic_scontrol sctrl;
 381
 382         u32 irqVector = *((u32 *)(irqarg));
 383         int cpu = smp_processor_id();
 384
 385         if (!gHvContext.HypercallPage)
 386                 return;
 387
 388         /* Check the version */
 389         rdmsrl(HV_X64_MSR_SVERSION, version);
 390
 391         DPRINT_INFO(VMBUS, "SynIC version: %llx", version);
 392
 393         gHvContext.synICMessagePage[cpu] = (void *)get_zeroed_page(GFP_ATOMIC);
 394
 395         if (gHvContext.synICMessagePage[cpu] == NULL) {
 396                 DPRINT_ERR(VMBUS,
 397                            "unable to allocate SYNIC message page!!");
 398                 goto Cleanup;
 399         }
 400
 401         gHvContext.synICEventPage[cpu] = (void *)get_zeroed_page(GFP_ATOMIC);
 402
 403         if (gHvContext.synICEventPage[cpu] == NULL) {
 404                 DPRINT_ERR(VMBUS,
 405                            "unable to allocate SYNIC event page!!");
 406                 goto Cleanup;
 407         }
 408
 409         /* Setup the Synic's message page */
 410         rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 411         simp.simp_enabled = 1;
 412         simp.base_simp_gpa = virt_to_phys(gHvContext.synICMessagePage[cpu])
 413                 >> PAGE_SHIFT;
 414
 415         DPRINT_DBG(VMBUS, "HV_X64_MSR_SIMP msr set to: %llx", simp.as_uint64);
 416
 417         wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 418
 419         /* Setup the Synic's event page */
 420         rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 421         siefp.siefp_enabled = 1;
 422         siefp.base_siefp_gpa = virt_to_phys(gHvContext.synICEventPage[cpu])
 423                 >> PAGE_SHIFT;
 424
 425         DPRINT_DBG(VMBUS, "HV_X64_MSR_SIEFP msr set to: %llx", siefp.as_uint64);
 426
 427         wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 428
 429         /* Setup the interception SINT. */
 430         /* wrmsrl((HV_X64_MSR_SINT0 + HV_SYNIC_INTERCEPTION_SINT_INDEX), */
 431         /*        interceptionSint.as_uint64); */
 432
 433         /* Setup the shared SINT. */
 434         rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 435
 436         sharedSint.as_uint64 = 0;
 437         sharedSint.vector = irqVector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */
 438         sharedSint.masked = false;
 439         sharedSint.auto_eoi = true;
 440
 441         DPRINT_DBG(VMBUS, "HV_X64_MSR_SINT1 msr set to: %llx",
 442                    sharedSint.as_uint64);
 443
 444         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 445
 446         /* Enable the global synic bit */
 447         rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
 448         sctrl.enable = 1;
 449
 450         wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
 451
 452         gHvContext.SynICInitialized = true;
 453         return;
 454
 455 Cleanup:
 456         if (gHvContext.synICEventPage[cpu])
 457                 osd_PageFree(gHvContext.synICEventPage[cpu], 1);
 458
 459         if (gHvContext.synICMessagePage[cpu])
 460                 osd_PageFree(gHvContext.synICMessagePage[cpu], 1);
 461         return;
 462 }
 463
 464 /*
 465  * HvSynicCleanup - Cleanup routine for HvSynicInit().
 466  */
 467 void HvSynicCleanup(void *arg)
 468 {
 469         union hv_synic_sint sharedSint;
 470         union hv_synic_simp simp;
 471         union hv_synic_siefp siefp;
 472         int cpu = smp_processor_id();
 473
 474         if (!gHvContext.SynICInitialized)
 475                 return;
 476
 477         rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 478
 479         sharedSint.masked = 1;
 480
 481         /* Need to correctly cleanup in the case of SMP!!! */
 482         /* Disable the interrupt */
 483         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 484
 485         rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 486         simp.simp_enabled = 0;
 487         simp.base_simp_gpa = 0;
 488
 489         wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 490
 491         rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 492         siefp.siefp_enabled = 0;
 493         siefp.base_siefp_gpa = 0;
 494
 495         wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 496
 497         osd_PageFree(gHvContext.synICMessagePage[cpu], 1);
 498         osd_PageFree(gHvContext.synICEventPage[cpu], 1);
 499 }