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 hv_context = {
  32         .synic_initialized      = false,
  33         .hypercall_page         = NULL,
  34         .signal_event_param     = NULL,
  35         .signal_event_buffer    = 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 = hv_context.hypercall_page;
 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 = hv_context.hypercall_page;
 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(hv_context.synic_event_page, 0, sizeof(void *) * MAX_NUM_CPUS);
 196         memset(hv_context.synic_message_page, 0,
 197                sizeof(void *) * MAX_NUM_CPUS);
 198
 199         if (!HvQueryHypervisorPresence()) {
 200                 DPRINT_ERR(VMBUS, "No Windows hypervisor detected!!");
 201                 goto Cleanup;
 202         }
 203
 204         DPRINT_INFO(VMBUS,
 205                     "Windows hypervisor detected! Retrieving more info...");
 206
 207         maxLeaf = HvQueryHypervisorInfo();
 208         /* HvQueryHypervisorFeatures(maxLeaf); */
 209
 210         /*
 211          * We only support running on top of Hyper-V
 212          */
 213         rdmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid);
 214
 215         if (hv_context.guestid != 0) {
 216                 DPRINT_ERR(VMBUS, "Unknown guest id (0x%llx)!!",
 217                                 hv_context.guestid);
 218                 goto Cleanup;
 219         }
 220
 221         /* Write our OS info */
 222         wrmsrl(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID);
 223         hv_context.guestid = HV_LINUX_GUEST_ID;
 224
 225         /* See if the hypercall page is already set */
 226         rdmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 227
 228         /*
 229         * Allocate the hypercall page memory
 230         * virtAddr = osd_PageAlloc(1);
 231         */
 232         virtAddr = osd_VirtualAllocExec(PAGE_SIZE);
 233
 234         if (!virtAddr) {
 235                 DPRINT_ERR(VMBUS,
 236                            "unable to allocate hypercall page!!");
 237                 goto Cleanup;
 238         }
 239
 240         hypercallMsr.enable = 1;
 241
 242         hypercallMsr.guest_physical_address = vmalloc_to_pfn(virtAddr);
 243         wrmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 244
 245         /* Confirm that hypercall page did get setup. */
 246         hypercallMsr.as_uint64 = 0;
 247         rdmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 248
 249         if (!hypercallMsr.enable) {
 250                 DPRINT_ERR(VMBUS, "unable to set hypercall page!!");
 251                 goto Cleanup;
 252         }
 253
 254         hv_context.hypercall_page = virtAddr;
 255
 256         DPRINT_INFO(VMBUS, "Hypercall page VA=%p, PA=0x%0llx",
 257                     hv_context.hypercall_page,
 258                     (u64)hypercallMsr.guest_physical_address << PAGE_SHIFT);
 259
 260         /* Setup the global signal event param for the signal event hypercall */
 261         hv_context.signal_event_buffer =
 262                         kmalloc(sizeof(struct hv_input_signal_event_buffer),
 263                                 GFP_KERNEL);
 264         if (!hv_context.signal_event_buffer)
 265                 goto Cleanup;
 266
 267         hv_context.signal_event_param =
 268                 (struct hv_input_signal_event *)
 269                         (ALIGN_UP((unsigned long)
 270                                   hv_context.signal_event_buffer,
 271                                   HV_HYPERCALL_PARAM_ALIGN));
 272         hv_context.signal_event_param->connectionid.asu32 = 0;
 273         hv_context.signal_event_param->connectionid.u.id =
 274                                                 VMBUS_EVENT_CONNECTION_ID;
 275         hv_context.signal_event_param->flag_number = 0;
 276         hv_context.signal_event_param->rsvdz = 0;
 277
 278         return ret;
 279
 280 Cleanup:
 281         if (virtAddr) {
 282                 if (hypercallMsr.enable) {
 283                         hypercallMsr.as_uint64 = 0;
 284                         wrmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 285                 }
 286
 287                 vfree(virtAddr);
 288         }
 289         ret = -1;
 290         return ret;
 291 }
 292
 293 /*
 294  * HvCleanup - Cleanup routine.
 295  *
 296  * This routine is called normally during driver unloading or exiting.
 297  */
 298 void HvCleanup(void)
 299 {
 300         union hv_x64_msr_hypercall_contents hypercallMsr;
 301
 302         kfree(hv_context.signal_event_buffer);
 303         hv_context.signal_event_buffer = NULL;
 304         hv_context.signal_event_param = NULL;
 305
 306         if (hv_context.hypercall_page) {
 307                 hypercallMsr.as_uint64 = 0;
 308                 wrmsrl(HV_X64_MSR_HYPERCALL, hypercallMsr.as_uint64);
 309                 vfree(hv_context.hypercall_page);
 310                 hv_context.hypercall_page = NULL;
 311         }
 312 }
 313
 314 /*
 315  * HvPostMessage - Post a message using the hypervisor message IPC.
 316  *
 317  * This involves a hypercall.
 318  */
 319 u16 HvPostMessage(union hv_connection_id connectionId,
 320                   enum hv_message_type messageType,
 321                   void *payload, size_t payloadSize)
 322 {
 323         struct alignedInput {
 324                 u64 alignment8;
 325                 struct hv_input_post_message msg;
 326         };
 327
 328         struct hv_input_post_message *alignedMsg;
 329         u16 status;
 330         unsigned long addr;
 331
 332         if (payloadSize > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
 333                 return -1;
 334
 335         addr = (unsigned long)kmalloc(sizeof(struct alignedInput), GFP_ATOMIC);
 336         if (!addr)
 337                 return -1;
 338
 339         alignedMsg = (struct hv_input_post_message *)
 340                         (ALIGN_UP(addr, HV_HYPERCALL_PARAM_ALIGN));
 341
 342         alignedMsg->connectionid = connectionId;
 343         alignedMsg->message_type = messageType;
 344         alignedMsg->payload_size = payloadSize;
 345         memcpy((void *)alignedMsg->payload, payload, payloadSize);
 346
 347         status = HvDoHypercall(HVCALL_POST_MESSAGE, alignedMsg, NULL) & 0xFFFF;
 348
 349         kfree((void *)addr);
 350
 351         return status;
 352 }
 353
 354
 355 /*
 356  * HvSignalEvent - Signal an event on the specified connection using the hypervisor event IPC.
 357  *
 358  * This involves a hypercall.
 359  */
 360 u16 HvSignalEvent(void)
 361 {
 362         u16 status;
 363
 364         status = HvDoHypercall(HVCALL_SIGNAL_EVENT,
 365                                hv_context.signal_event_param,
 366                                NULL) & 0xFFFF;
 367         return status;
 368 }
 369
 370 /*
 371  * HvSynicInit - Initialize the Synthethic Interrupt Controller.
 372  *
 373  * If it is already initialized by another entity (ie x2v shim), we need to
 374  * retrieve the initialized message and event pages.  Otherwise, we create and
 375  * initialize the message and event pages.
 376  */
 377 void HvSynicInit(void *irqarg)
 378 {
 379         u64 version;
 380         union hv_synic_simp simp;
 381         union hv_synic_siefp siefp;
 382         union hv_synic_sint sharedSint;
 383         union hv_synic_scontrol sctrl;
 384
 385         u32 irqVector = *((u32 *)(irqarg));
 386         int cpu = smp_processor_id();
 387
 388         if (!hv_context.hypercall_page)
 389                 return;
 390
 391         /* Check the version */
 392         rdmsrl(HV_X64_MSR_SVERSION, version);
 393
 394         DPRINT_INFO(VMBUS, "SynIC version: %llx", version);
 395
 396         hv_context.synic_message_page[cpu] =
 397                 (void *)get_zeroed_page(GFP_ATOMIC);
 398
 399         if (hv_context.synic_message_page[cpu] == NULL) {
 400                 DPRINT_ERR(VMBUS,
 401                            "unable to allocate SYNIC message page!!");
 402                 goto Cleanup;
 403         }
 404
 405         hv_context.synic_event_page[cpu] =
 406                 (void *)get_zeroed_page(GFP_ATOMIC);
 407
 408         if (hv_context.synic_event_page[cpu] == NULL) {
 409                 DPRINT_ERR(VMBUS,
 410                            "unable to allocate SYNIC event page!!");
 411                 goto Cleanup;
 412         }
 413
 414         /* Setup the Synic's message page */
 415         rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 416         simp.simp_enabled = 1;
 417         simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu])
 418                 >> PAGE_SHIFT;
 419
 420         DPRINT_DBG(VMBUS, "HV_X64_MSR_SIMP msr set to: %llx", simp.as_uint64);
 421
 422         wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 423
 424         /* Setup the Synic's event page */
 425         rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 426         siefp.siefp_enabled = 1;
 427         siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu])
 428                 >> PAGE_SHIFT;
 429
 430         DPRINT_DBG(VMBUS, "HV_X64_MSR_SIEFP msr set to: %llx", siefp.as_uint64);
 431
 432         wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 433
 434         /* Setup the interception SINT. */
 435         /* wrmsrl((HV_X64_MSR_SINT0 + HV_SYNIC_INTERCEPTION_SINT_INDEX), */
 436         /*        interceptionSint.as_uint64); */
 437
 438         /* Setup the shared SINT. */
 439         rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 440
 441         sharedSint.as_uint64 = 0;
 442         sharedSint.vector = irqVector; /* HV_SHARED_SINT_IDT_VECTOR + 0x20; */
 443         sharedSint.masked = false;
 444         sharedSint.auto_eoi = true;
 445
 446         DPRINT_DBG(VMBUS, "HV_X64_MSR_SINT1 msr set to: %llx",
 447                    sharedSint.as_uint64);
 448
 449         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 450
 451         /* Enable the global synic bit */
 452         rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
 453         sctrl.enable = 1;
 454
 455         wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
 456
 457         hv_context.synic_initialized = true;
 458         return;
 459
 460 Cleanup:
 461         if (hv_context.synic_event_page[cpu])
 462                 osd_PageFree(hv_context.synic_event_page[cpu], 1);
 463
 464         if (hv_context.synic_message_page[cpu])
 465                 osd_PageFree(hv_context.synic_message_page[cpu], 1);
 466         return;
 467 }
 468
 469 /*
 470  * HvSynicCleanup - Cleanup routine for HvSynicInit().
 471  */
 472 void HvSynicCleanup(void *arg)
 473 {
 474         union hv_synic_sint sharedSint;
 475         union hv_synic_simp simp;
 476         union hv_synic_siefp siefp;
 477         int cpu = smp_processor_id();
 478
 479         if (!hv_context.synic_initialized)
 480                 return;
 481
 482         rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 483
 484         sharedSint.masked = 1;
 485
 486         /* Need to correctly cleanup in the case of SMP!!! */
 487         /* Disable the interrupt */
 488         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.as_uint64);
 489
 490         rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 491         simp.simp_enabled = 0;
 492         simp.base_simp_gpa = 0;
 493
 494         wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
 495
 496         rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 497         siefp.siefp_enabled = 0;
 498         siefp.base_siefp_gpa = 0;
 499
 500         wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
 501
 502         osd_PageFree(hv_context.synic_message_page[cpu], 1);
 503         osd_PageFree(hv_context.synic_event_page[cpu], 1);
 504 }