arch/mips/kvm/kvm_mips.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * KVM/MIPS: MIPS specific KVM APIs
   7  *
   8  * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
   9  * Authors: Sanjay Lal <sanjayl@kymasys.com>
  10 */
  11
  12 #include <linux/errno.h>
  13 #include <linux/err.h>
  14 #include <linux/module.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/fs.h>
  17 #include <linux/bootmem.h>
  18 #include <asm/page.h>
  19 #include <asm/cacheflush.h>
  20 #include <asm/mmu_context.h>
  21
  22 #include <linux/kvm_host.h>
  23
  24 #include "kvm_mips_int.h"
  25 #include "kvm_mips_comm.h"
  26
  27 #define CREATE_TRACE_POINTS
  28 #include "trace.h"
  29
  30 #ifndef VECTORSPACING
  31 #define VECTORSPACING 0x100     /* for EI/VI mode */
  32 #endif
  33
  34 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
  35 struct kvm_stats_debugfs_item debugfs_entries[] = {
  36         { "wait", VCPU_STAT(wait_exits) },
  37         { "cache", VCPU_STAT(cache_exits) },
  38         { "signal", VCPU_STAT(signal_exits) },
  39         { "interrupt", VCPU_STAT(int_exits) },
  40         { "cop_unsuable", VCPU_STAT(cop_unusable_exits) },
  41         { "tlbmod", VCPU_STAT(tlbmod_exits) },
  42         { "tlbmiss_ld", VCPU_STAT(tlbmiss_ld_exits) },
  43         { "tlbmiss_st", VCPU_STAT(tlbmiss_st_exits) },
  44         { "addrerr_st", VCPU_STAT(addrerr_st_exits) },
  45         { "addrerr_ld", VCPU_STAT(addrerr_ld_exits) },
  46         { "syscall", VCPU_STAT(syscall_exits) },
  47         { "resvd_inst", VCPU_STAT(resvd_inst_exits) },
  48         { "break_inst", VCPU_STAT(break_inst_exits) },
  49         { "flush_dcache", VCPU_STAT(flush_dcache_exits) },
  50         { "halt_wakeup", VCPU_STAT(halt_wakeup) },
  51         {NULL}
  52 };
  53
  54 static int kvm_mips_reset_vcpu(struct kvm_vcpu *vcpu)
  55 {
  56         int i;
  57         for_each_possible_cpu(i) {
  58                 vcpu->arch.guest_kernel_asid[i] = 0;
  59                 vcpu->arch.guest_user_asid[i] = 0;
  60         }
  61         return 0;
  62 }
  63
  64 gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
  65 {
  66         return gfn;
  67 }
  68
  69 /* XXXKYMA: We are simulatoring a processor that has the WII bit set in Config7, so we
  70  * are "runnable" if interrupts are pending
  71  */
  72 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
  73 {
  74         return !!(vcpu->arch.pending_exceptions);
  75 }
  76
  77 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  78 {
  79         return 1;
  80 }
  81
  82 int kvm_arch_hardware_enable(void *garbage)
  83 {
  84         return 0;
  85 }
  86
  87 void kvm_arch_hardware_disable(void *garbage)
  88 {
  89 }
  90
  91 int kvm_arch_hardware_setup(void)
  92 {
  93         return 0;
  94 }
  95
  96 void kvm_arch_hardware_unsetup(void)
  97 {
  98 }
  99
 100 void kvm_arch_check_processor_compat(void *rtn)
 101 {
 102         int *r = (int *)rtn;
 103         *r = 0;
 104         return;
 105 }
 106
 107 static void kvm_mips_init_tlbs(struct kvm *kvm)
 108 {
 109         unsigned long wired;
 110
 111         /* Add a wired entry to the TLB, it is used to map the commpage to the Guest kernel */
 112         wired = read_c0_wired();
 113         write_c0_wired(wired + 1);
 114         mtc0_tlbw_hazard();
 115         kvm->arch.commpage_tlb = wired;
 116
 117         kvm_debug("[%d] commpage TLB: %d\n", smp_processor_id(),
 118                   kvm->arch.commpage_tlb);
 119 }
 120
 121 static void kvm_mips_init_vm_percpu(void *arg)
 122 {
 123         struct kvm *kvm = (struct kvm *)arg;
 124
 125         kvm_mips_init_tlbs(kvm);
 126         kvm_mips_callbacks->vm_init(kvm);
 127
 128 }
 129
 130 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 131 {
 132         if (atomic_inc_return(&kvm_mips_instance) == 1) {
 133                 kvm_info("%s: 1st KVM instance, setup host TLB parameters\n",
 134                          __func__);
 135                 on_each_cpu(kvm_mips_init_vm_percpu, kvm, 1);
 136         }
 137
 138
 139         return 0;
 140 }
 141
 142 void kvm_mips_free_vcpus(struct kvm *kvm)
 143 {
 144         unsigned int i;
 145         struct kvm_vcpu *vcpu;
 146
 147         /* Put the pages we reserved for the guest pmap */
 148         for (i = 0; i < kvm->arch.guest_pmap_npages; i++) {
 149                 if (kvm->arch.guest_pmap[i] != KVM_INVALID_PAGE)
 150                         kvm_mips_release_pfn_clean(kvm->arch.guest_pmap[i]);
 151         }
 152
 153         if (kvm->arch.guest_pmap)
 154                 kfree(kvm->arch.guest_pmap);
 155
 156         kvm_for_each_vcpu(i, vcpu, kvm) {
 157                 kvm_arch_vcpu_free(vcpu);
 158         }
 159
 160         mutex_lock(&kvm->lock);
 161
 162         for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
 163                 kvm->vcpus[i] = NULL;
 164
 165         atomic_set(&kvm->online_vcpus, 0);
 166
 167         mutex_unlock(&kvm->lock);
 168 }
 169
 170 void kvm_arch_sync_events(struct kvm *kvm)
 171 {
 172 }
 173
 174 static void kvm_mips_uninit_tlbs(void *arg)
 175 {
 176         /* Restore wired count */
 177         write_c0_wired(0);
 178         mtc0_tlbw_hazard();
 179         /* Clear out all the TLBs */
 180         kvm_local_flush_tlb_all();
 181 }
 182
 183 void kvm_arch_destroy_vm(struct kvm *kvm)
 184 {
 185         kvm_mips_free_vcpus(kvm);
 186
 187         /* If this is the last instance, restore wired count */
 188         if (atomic_dec_return(&kvm_mips_instance) == 0) {
 189                 kvm_info("%s: last KVM instance, restoring TLB parameters\n",
 190                          __func__);
 191                 on_each_cpu(kvm_mips_uninit_tlbs, NULL, 1);
 192         }
 193 }
 194
 195 long
 196 kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 197 {
 198         return -ENOIOCTLCMD;
 199 }
 200
 201 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
 202                            struct kvm_memory_slot *dont)
 203 {
 204 }
 205
 206 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
 207                             unsigned long npages)
 208 {
 209         return 0;
 210 }
 211
 212 void kvm_arch_memslots_updated(struct kvm *kvm)
 213 {
 214 }
 215
 216 int kvm_arch_prepare_memory_region(struct kvm *kvm,
 217                                 struct kvm_memory_slot *memslot,
 218                                 struct kvm_userspace_memory_region *mem,
 219                                 enum kvm_mr_change change)
 220 {
 221         return 0;
 222 }
 223
 224 void kvm_arch_commit_memory_region(struct kvm *kvm,
 225                                 struct kvm_userspace_memory_region *mem,
 226                                 const struct kvm_memory_slot *old,
 227                                 enum kvm_mr_change change)
 228 {
 229         unsigned long npages = 0;
 230         int i, err = 0;
 231
 232         kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
 233                   __func__, kvm, mem->slot, mem->guest_phys_addr,
 234                   mem->memory_size, mem->userspace_addr);
 235
 236         /* Setup Guest PMAP table */
 237         if (!kvm->arch.guest_pmap) {
 238                 if (mem->slot == 0)
 239                         npages = mem->memory_size >> PAGE_SHIFT;
 240
 241                 if (npages) {
 242                         kvm->arch.guest_pmap_npages = npages;
 243                         kvm->arch.guest_pmap =
 244                             kzalloc(npages * sizeof(unsigned long), GFP_KERNEL);
 245
 246                         if (!kvm->arch.guest_pmap) {
 247                                 kvm_err("Failed to allocate guest PMAP");
 248                                 err = -ENOMEM;
 249                                 goto out;
 250                         }
 251
 252                         kvm_info
 253                             ("Allocated space for Guest PMAP Table (%ld pages) @ %p\n",
 254                              npages, kvm->arch.guest_pmap);
 255
 256                         /* Now setup the page table */
 257                         for (i = 0; i < npages; i++) {
 258                                 kvm->arch.guest_pmap[i] = KVM_INVALID_PAGE;
 259                         }
 260                 }
 261         }
 262 out:
 263         return;
 264 }
 265
 266 void kvm_arch_flush_shadow_all(struct kvm *kvm)
 267 {
 268 }
 269
 270 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
 271                                    struct kvm_memory_slot *slot)
 272 {
 273 }
 274
 275 void kvm_arch_flush_shadow(struct kvm *kvm)
 276 {
 277 }
 278
 279 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 280 {
 281         extern char mips32_exception[], mips32_exceptionEnd[];
 282         extern char mips32_GuestException[], mips32_GuestExceptionEnd[];
 283         int err, size, offset;
 284         void *gebase;
 285         int i;
 286
 287         struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
 288
 289         if (!vcpu) {
 290                 err = -ENOMEM;
 291                 goto out;
 292         }
 293
 294         err = kvm_vcpu_init(vcpu, kvm, id);
 295
 296         if (err)
 297                 goto out_free_cpu;
 298
 299         kvm_info("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
 300
 301         /* Allocate space for host mode exception handlers that handle
 302          * guest mode exits
 303          */
 304         if (cpu_has_veic || cpu_has_vint) {
 305                 size = 0x200 + VECTORSPACING * 64;
 306         } else {
 307                 size = 0x200;
 308         }
 309
 310         /* Save Linux EBASE */
 311         vcpu->arch.host_ebase = (void *)read_c0_ebase();
 312
 313         gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
 314
 315         if (!gebase) {
 316                 err = -ENOMEM;
 317                 goto out_free_cpu;
 318         }
 319         kvm_info("Allocated %d bytes for KVM Exception Handlers @ %p\n",
 320                  ALIGN(size, PAGE_SIZE), gebase);
 321
 322         /* Save new ebase */
 323         vcpu->arch.guest_ebase = gebase;
 324
 325         /* Copy L1 Guest Exception handler to correct offset */
 326
 327         /* TLB Refill, EXL = 0 */
 328         memcpy(gebase, mips32_exception,
 329                mips32_exceptionEnd - mips32_exception);
 330
 331         /* General Exception Entry point */
 332         memcpy(gebase + 0x180, mips32_exception,
 333                mips32_exceptionEnd - mips32_exception);
 334
 335         /* For vectored interrupts poke the exception code @ all offsets 0-7 */
 336         for (i = 0; i < 8; i++) {
 337                 kvm_debug("L1 Vectored handler @ %p\n",
 338                           gebase + 0x200 + (i * VECTORSPACING));
 339                 memcpy(gebase + 0x200 + (i * VECTORSPACING), mips32_exception,
 340                        mips32_exceptionEnd - mips32_exception);
 341         }
 342
 343         /* General handler, relocate to unmapped space for sanity's sake */
 344         offset = 0x2000;
 345         kvm_info("Installing KVM Exception handlers @ %p, %#x bytes\n",
 346                  gebase + offset,
 347                  mips32_GuestExceptionEnd - mips32_GuestException);
 348
 349         memcpy(gebase + offset, mips32_GuestException,
 350                mips32_GuestExceptionEnd - mips32_GuestException);
 351
 352         /* Invalidate the icache for these ranges */
 353         mips32_SyncICache((unsigned long) gebase, ALIGN(size, PAGE_SIZE));
 354
 355         /* Allocate comm page for guest kernel, a TLB will be reserved for mapping GVA @ 0xFFFF8000 to this page */
 356         vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
 357
 358         if (!vcpu->arch.kseg0_commpage) {
 359                 err = -ENOMEM;
 360                 goto out_free_gebase;
 361         }
 362
 363         kvm_info("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
 364         kvm_mips_commpage_init(vcpu);
 365
 366         /* Init */
 367         vcpu->arch.last_sched_cpu = -1;
 368
 369         /* Start off the timer */
 370         kvm_mips_emulate_count(vcpu);
 371
 372         return vcpu;
 373
 374 out_free_gebase:
 375         kfree(gebase);
 376
 377 out_free_cpu:
 378         kfree(vcpu);
 379
 380 out:
 381         return ERR_PTR(err);
 382 }
 383
 384 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 385 {
 386         hrtimer_cancel(&vcpu->arch.comparecount_timer);
 387
 388         kvm_vcpu_uninit(vcpu);
 389
 390         kvm_mips_dump_stats(vcpu);
 391
 392         if (vcpu->arch.guest_ebase)
 393                 kfree(vcpu->arch.guest_ebase);
 394
 395         if (vcpu->arch.kseg0_commpage)
 396                 kfree(vcpu->arch.kseg0_commpage);
 397
 398 }
 399
 400 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 401 {
 402         kvm_arch_vcpu_free(vcpu);
 403 }
 404
 405 int
 406 kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 407                                     struct kvm_guest_debug *dbg)
 408 {
 409         return -ENOIOCTLCMD;
 410 }
 411
 412 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 413 {
 414         int r = 0;
 415         sigset_t sigsaved;
 416
 417         if (vcpu->sigset_active)
 418                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 419
 420         if (vcpu->mmio_needed) {
 421                 if (!vcpu->mmio_is_write)
 422                         kvm_mips_complete_mmio_load(vcpu, run);
 423                 vcpu->mmio_needed = 0;
 424         }
 425
 426         /* Check if we have any exceptions/interrupts pending */
 427         kvm_mips_deliver_interrupts(vcpu,
 428                                     kvm_read_c0_guest_cause(vcpu->arch.cop0));
 429
 430         local_irq_disable();
 431         kvm_guest_enter();
 432
 433         r = __kvm_mips_vcpu_run(run, vcpu);
 434
 435         kvm_guest_exit();
 436         local_irq_enable();
 437
 438         if (vcpu->sigset_active)
 439                 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
 440
 441         return r;
 442 }
 443
 444 int
 445 kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_mips_interrupt *irq)
 446 {
 447         int intr = (int)irq->irq;
 448         struct kvm_vcpu *dvcpu = NULL;
 449
 450         if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
 451                 kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
 452                           (int)intr);
 453
 454         if (irq->cpu == -1)
 455                 dvcpu = vcpu;
 456         else
 457                 dvcpu = vcpu->kvm->vcpus[irq->cpu];
 458
 459         if (intr == 2 || intr == 3 || intr == 4) {
 460                 kvm_mips_callbacks->queue_io_int(dvcpu, irq);
 461
 462         } else if (intr == -2 || intr == -3 || intr == -4) {
 463                 kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
 464         } else {
 465                 kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
 466                         irq->cpu, irq->irq);
 467                 return -EINVAL;
 468         }
 469
 470         dvcpu->arch.wait = 0;
 471
 472         if (waitqueue_active(&dvcpu->wq)) {
 473                 wake_up_interruptible(&dvcpu->wq);
 474         }
 475
 476         return 0;
 477 }
 478
 479 int
 480 kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 481                                 struct kvm_mp_state *mp_state)
 482 {
 483         return -ENOIOCTLCMD;
 484 }
 485
 486 int
 487 kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 488                                 struct kvm_mp_state *mp_state)
 489 {
 490         return -ENOIOCTLCMD;
 491 }
 492
 493 #define MIPS_CP0_32(_R, _S)                                     \
 494         (KVM_REG_MIPS | KVM_REG_SIZE_U32 | 0x10000 | (8 * (_R) + (_S)))
 495
 496 #define MIPS_CP0_64(_R, _S)                                     \
 497         (KVM_REG_MIPS | KVM_REG_SIZE_U64 | 0x10000 | (8 * (_R) + (_S)))
 498
 499 #define KVM_REG_MIPS_CP0_INDEX          MIPS_CP0_32(0, 0)
 500 #define KVM_REG_MIPS_CP0_ENTRYLO0       MIPS_CP0_64(2, 0)
 501 #define KVM_REG_MIPS_CP0_ENTRYLO1       MIPS_CP0_64(3, 0)
 502 #define KVM_REG_MIPS_CP0_CONTEXT        MIPS_CP0_64(4, 0)
 503 #define KVM_REG_MIPS_CP0_USERLOCAL      MIPS_CP0_64(4, 2)
 504 #define KVM_REG_MIPS_CP0_PAGEMASK       MIPS_CP0_32(5, 0)
 505 #define KVM_REG_MIPS_CP0_PAGEGRAIN      MIPS_CP0_32(5, 1)
 506 #define KVM_REG_MIPS_CP0_WIRED          MIPS_CP0_32(6, 0)
 507 #define KVM_REG_MIPS_CP0_HWRENA         MIPS_CP0_32(7, 0)
 508 #define KVM_REG_MIPS_CP0_BADVADDR       MIPS_CP0_64(8, 0)
 509 #define KVM_REG_MIPS_CP0_COUNT          MIPS_CP0_32(9, 0)
 510 #define KVM_REG_MIPS_CP0_ENTRYHI        MIPS_CP0_64(10, 0)
 511 #define KVM_REG_MIPS_CP0_COMPARE        MIPS_CP0_32(11, 0)
 512 #define KVM_REG_MIPS_CP0_STATUS         MIPS_CP0_32(12, 0)
 513 #define KVM_REG_MIPS_CP0_CAUSE          MIPS_CP0_32(13, 0)
 514 #define KVM_REG_MIPS_CP0_EBASE          MIPS_CP0_64(15, 1)
 515 #define KVM_REG_MIPS_CP0_CONFIG         MIPS_CP0_32(16, 0)
 516 #define KVM_REG_MIPS_CP0_CONFIG1        MIPS_CP0_32(16, 1)
 517 #define KVM_REG_MIPS_CP0_CONFIG2        MIPS_CP0_32(16, 2)
 518 #define KVM_REG_MIPS_CP0_CONFIG3        MIPS_CP0_32(16, 3)
 519 #define KVM_REG_MIPS_CP0_CONFIG7        MIPS_CP0_32(16, 7)
 520 #define KVM_REG_MIPS_CP0_XCONTEXT       MIPS_CP0_64(20, 0)
 521 #define KVM_REG_MIPS_CP0_ERROREPC       MIPS_CP0_64(30, 0)
 522
 523 static u64 kvm_mips_get_one_regs[] = {
 524         KVM_REG_MIPS_R0,
 525         KVM_REG_MIPS_R1,
 526         KVM_REG_MIPS_R2,
 527         KVM_REG_MIPS_R3,
 528         KVM_REG_MIPS_R4,
 529         KVM_REG_MIPS_R5,
 530         KVM_REG_MIPS_R6,
 531         KVM_REG_MIPS_R7,
 532         KVM_REG_MIPS_R8,
 533         KVM_REG_MIPS_R9,
 534         KVM_REG_MIPS_R10,
 535         KVM_REG_MIPS_R11,
 536         KVM_REG_MIPS_R12,
 537         KVM_REG_MIPS_R13,
 538         KVM_REG_MIPS_R14,
 539         KVM_REG_MIPS_R15,
 540         KVM_REG_MIPS_R16,
 541         KVM_REG_MIPS_R17,
 542         KVM_REG_MIPS_R18,
 543         KVM_REG_MIPS_R19,
 544         KVM_REG_MIPS_R20,
 545         KVM_REG_MIPS_R21,
 546         KVM_REG_MIPS_R22,
 547         KVM_REG_MIPS_R23,
 548         KVM_REG_MIPS_R24,
 549         KVM_REG_MIPS_R25,
 550         KVM_REG_MIPS_R26,
 551         KVM_REG_MIPS_R27,
 552         KVM_REG_MIPS_R28,
 553         KVM_REG_MIPS_R29,
 554         KVM_REG_MIPS_R30,
 555         KVM_REG_MIPS_R31,
 556
 557         KVM_REG_MIPS_HI,
 558         KVM_REG_MIPS_LO,
 559         KVM_REG_MIPS_PC,
 560
 561         KVM_REG_MIPS_CP0_INDEX,
 562         KVM_REG_MIPS_CP0_CONTEXT,
 563         KVM_REG_MIPS_CP0_PAGEMASK,
 564         KVM_REG_MIPS_CP0_WIRED,
 565         KVM_REG_MIPS_CP0_BADVADDR,
 566         KVM_REG_MIPS_CP0_ENTRYHI,
 567         KVM_REG_MIPS_CP0_STATUS,
 568         KVM_REG_MIPS_CP0_CAUSE,
 569         /* EPC set via kvm_regs, et al. */
 570         KVM_REG_MIPS_CP0_CONFIG,
 571         KVM_REG_MIPS_CP0_CONFIG1,
 572         KVM_REG_MIPS_CP0_CONFIG2,
 573         KVM_REG_MIPS_CP0_CONFIG3,
 574         KVM_REG_MIPS_CP0_CONFIG7,
 575         KVM_REG_MIPS_CP0_ERROREPC
 576 };
 577
 578 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
 579                             const struct kvm_one_reg *reg)
 580 {
 581         struct mips_coproc *cop0 = vcpu->arch.cop0;
 582         s64 v;
 583
 584         switch (reg->id) {
 585         case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
 586                 v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
 587                 break;
 588         case KVM_REG_MIPS_HI:
 589                 v = (long)vcpu->arch.hi;
 590                 break;
 591         case KVM_REG_MIPS_LO:
 592                 v = (long)vcpu->arch.lo;
 593                 break;
 594         case KVM_REG_MIPS_PC:
 595                 v = (long)vcpu->arch.pc;
 596                 break;
 597
 598         case KVM_REG_MIPS_CP0_INDEX:
 599                 v = (long)kvm_read_c0_guest_index(cop0);
 600                 break;
 601         case KVM_REG_MIPS_CP0_CONTEXT:
 602                 v = (long)kvm_read_c0_guest_context(cop0);
 603                 break;
 604         case KVM_REG_MIPS_CP0_PAGEMASK:
 605                 v = (long)kvm_read_c0_guest_pagemask(cop0);
 606                 break;
 607         case KVM_REG_MIPS_CP0_WIRED:
 608                 v = (long)kvm_read_c0_guest_wired(cop0);
 609                 break;
 610         case KVM_REG_MIPS_CP0_BADVADDR:
 611                 v = (long)kvm_read_c0_guest_badvaddr(cop0);
 612                 break;
 613         case KVM_REG_MIPS_CP0_ENTRYHI:
 614                 v = (long)kvm_read_c0_guest_entryhi(cop0);
 615                 break;
 616         case KVM_REG_MIPS_CP0_STATUS:
 617                 v = (long)kvm_read_c0_guest_status(cop0);
 618                 break;
 619         case KVM_REG_MIPS_CP0_CAUSE:
 620                 v = (long)kvm_read_c0_guest_cause(cop0);
 621                 break;
 622         case KVM_REG_MIPS_CP0_ERROREPC:
 623                 v = (long)kvm_read_c0_guest_errorepc(cop0);
 624                 break;
 625         case KVM_REG_MIPS_CP0_CONFIG:
 626                 v = (long)kvm_read_c0_guest_config(cop0);
 627                 break;
 628         case KVM_REG_MIPS_CP0_CONFIG1:
 629                 v = (long)kvm_read_c0_guest_config1(cop0);
 630                 break;
 631         case KVM_REG_MIPS_CP0_CONFIG2:
 632                 v = (long)kvm_read_c0_guest_config2(cop0);
 633                 break;
 634         case KVM_REG_MIPS_CP0_CONFIG3:
 635                 v = (long)kvm_read_c0_guest_config3(cop0);
 636                 break;
 637         case KVM_REG_MIPS_CP0_CONFIG7:
 638                 v = (long)kvm_read_c0_guest_config7(cop0);
 639                 break;
 640         default:
 641                 return -EINVAL;
 642         }
 643         if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
 644                 u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
 645                 return put_user(v, uaddr64);
 646         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
 647                 u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
 648                 u32 v32 = (u32)v;
 649                 return put_user(v32, uaddr32);
 650         } else {
 651                 return -EINVAL;
 652         }
 653 }
 654
 655 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
 656                             const struct kvm_one_reg *reg)
 657 {
 658         struct mips_coproc *cop0 = vcpu->arch.cop0;
 659         u64 v;
 660
 661         if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
 662                 u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
 663
 664                 if (get_user(v, uaddr64) != 0)
 665                         return -EFAULT;
 666         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
 667                 u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
 668                 s32 v32;
 669
 670                 if (get_user(v32, uaddr32) != 0)
 671                         return -EFAULT;
 672                 v = (s64)v32;
 673         } else {
 674                 return -EINVAL;
 675         }
 676
 677         switch (reg->id) {
 678         case KVM_REG_MIPS_R0:
 679                 /* Silently ignore requests to set $0 */
 680                 break;
 681         case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
 682                 vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
 683                 break;
 684         case KVM_REG_MIPS_HI:
 685                 vcpu->arch.hi = v;
 686                 break;
 687         case KVM_REG_MIPS_LO:
 688                 vcpu->arch.lo = v;
 689                 break;
 690         case KVM_REG_MIPS_PC:
 691                 vcpu->arch.pc = v;
 692                 break;
 693
 694         case KVM_REG_MIPS_CP0_INDEX:
 695                 kvm_write_c0_guest_index(cop0, v);
 696                 break;
 697         case KVM_REG_MIPS_CP0_CONTEXT:
 698                 kvm_write_c0_guest_context(cop0, v);
 699                 break;
 700         case KVM_REG_MIPS_CP0_PAGEMASK:
 701                 kvm_write_c0_guest_pagemask(cop0, v);
 702                 break;
 703         case KVM_REG_MIPS_CP0_WIRED:
 704                 kvm_write_c0_guest_wired(cop0, v);
 705                 break;
 706         case KVM_REG_MIPS_CP0_BADVADDR:
 707                 kvm_write_c0_guest_badvaddr(cop0, v);
 708                 break;
 709         case KVM_REG_MIPS_CP0_ENTRYHI:
 710                 kvm_write_c0_guest_entryhi(cop0, v);
 711                 break;
 712         case KVM_REG_MIPS_CP0_STATUS:
 713                 kvm_write_c0_guest_status(cop0, v);
 714                 break;
 715         case KVM_REG_MIPS_CP0_CAUSE:
 716                 kvm_write_c0_guest_cause(cop0, v);
 717                 break;
 718         case KVM_REG_MIPS_CP0_ERROREPC:
 719                 kvm_write_c0_guest_errorepc(cop0, v);
 720                 break;
 721         default:
 722                 return -EINVAL;
 723         }
 724         return 0;
 725 }
 726
 727 long
 728 kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 729 {
 730         struct kvm_vcpu *vcpu = filp->private_data;
 731         void __user *argp = (void __user *)arg;
 732         long r;
 733
 734         switch (ioctl) {
 735         case KVM_SET_ONE_REG:
 736         case KVM_GET_ONE_REG: {
 737                 struct kvm_one_reg reg;
 738                 if (copy_from_user(&reg, argp, sizeof(reg)))
 739                         return -EFAULT;
 740                 if (ioctl == KVM_SET_ONE_REG)
 741                         return kvm_mips_set_reg(vcpu, &reg);
 742                 else
 743                         return kvm_mips_get_reg(vcpu, &reg);
 744         }
 745         case KVM_GET_REG_LIST: {
 746                 struct kvm_reg_list __user *user_list = argp;
 747                 u64 __user *reg_dest;
 748                 struct kvm_reg_list reg_list;
 749                 unsigned n;
 750
 751                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
 752                         return -EFAULT;
 753                 n = reg_list.n;
 754                 reg_list.n = ARRAY_SIZE(kvm_mips_get_one_regs);
 755                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
 756                         return -EFAULT;
 757                 if (n < reg_list.n)
 758                         return -E2BIG;
 759                 reg_dest = user_list->reg;
 760                 if (copy_to_user(reg_dest, kvm_mips_get_one_regs,
 761                                  sizeof(kvm_mips_get_one_regs)))
 762                         return -EFAULT;
 763                 return 0;
 764         }
 765         case KVM_NMI:
 766                 /* Treat the NMI as a CPU reset */
 767                 r = kvm_mips_reset_vcpu(vcpu);
 768                 break;
 769         case KVM_INTERRUPT:
 770                 {
 771                         struct kvm_mips_interrupt irq;
 772                         r = -EFAULT;
 773                         if (copy_from_user(&irq, argp, sizeof(irq)))
 774                                 goto out;
 775
 776                         kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
 777                                   irq.irq);
 778
 779                         r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
 780                         break;
 781                 }
 782         default:
 783                 r = -ENOIOCTLCMD;
 784         }
 785
 786 out:
 787         return r;
 788 }
 789
 790 /*
 791  * Get (and clear) the dirty memory log for a memory slot.
 792  */
 793 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 794 {
 795         struct kvm_memory_slot *memslot;
 796         unsigned long ga, ga_end;
 797         int is_dirty = 0;
 798         int r;
 799         unsigned long n;
 800
 801         mutex_lock(&kvm->slots_lock);
 802
 803         r = kvm_get_dirty_log(kvm, log, &is_dirty);
 804         if (r)
 805                 goto out;
 806
 807         /* If nothing is dirty, don't bother messing with page tables. */
 808         if (is_dirty) {
 809                 memslot = &kvm->memslots->memslots[log->slot];
 810
 811                 ga = memslot->base_gfn << PAGE_SHIFT;
 812                 ga_end = ga + (memslot->npages << PAGE_SHIFT);
 813
 814                 printk("%s: dirty, ga: %#lx, ga_end %#lx\n", __func__, ga,
 815                        ga_end);
 816
 817                 n = kvm_dirty_bitmap_bytes(memslot);
 818                 memset(memslot->dirty_bitmap, 0, n);
 819         }
 820
 821         r = 0;
 822 out:
 823         mutex_unlock(&kvm->slots_lock);
 824         return r;
 825
 826 }
 827
 828 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 829 {
 830         long r;
 831
 832         switch (ioctl) {
 833         default:
 834                 r = -ENOIOCTLCMD;
 835         }
 836
 837         return r;
 838 }
 839
 840 int kvm_arch_init(void *opaque)
 841 {
 842         int ret;
 843
 844         if (kvm_mips_callbacks) {
 845                 kvm_err("kvm: module already exists\n");
 846                 return -EEXIST;
 847         }
 848
 849         ret = kvm_mips_emulation_init(&kvm_mips_callbacks);
 850
 851         return ret;
 852 }
 853
 854 void kvm_arch_exit(void)
 855 {
 856         kvm_mips_callbacks = NULL;
 857 }
 858
 859 int
 860 kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
 861 {
 862         return -ENOIOCTLCMD;
 863 }
 864
 865 int
 866 kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)
 867 {
 868         return -ENOIOCTLCMD;
 869 }
 870
 871 int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 872 {
 873         return 0;
 874 }
 875
 876 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 877 {
 878         return -ENOIOCTLCMD;
 879 }
 880
 881 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 882 {
 883         return -ENOIOCTLCMD;
 884 }
 885
 886 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 887 {
 888         return VM_FAULT_SIGBUS;
 889 }
 890
 891 int kvm_dev_ioctl_check_extension(long ext)
 892 {
 893         int r;
 894
 895         switch (ext) {
 896         case KVM_CAP_ONE_REG:
 897                 r = 1;
 898                 break;
 899         case KVM_CAP_COALESCED_MMIO:
 900                 r = KVM_COALESCED_MMIO_PAGE_OFFSET;
 901                 break;
 902         default:
 903                 r = 0;
 904                 break;
 905         }
 906         return r;
 907 }
 908
 909 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 910 {
 911         return kvm_mips_pending_timer(vcpu);
 912 }
 913
 914 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
 915 {
 916         int i;
 917         struct mips_coproc *cop0;
 918
 919         if (!vcpu)
 920                 return -1;
 921
 922         printk("VCPU Register Dump:\n");
 923         printk("\tpc = 0x%08lx\n", vcpu->arch.pc);;
 924         printk("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
 925
 926         for (i = 0; i < 32; i += 4) {
 927                 printk("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
 928                        vcpu->arch.gprs[i],
 929                        vcpu->arch.gprs[i + 1],
 930                        vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
 931         }
 932         printk("\thi: 0x%08lx\n", vcpu->arch.hi);
 933         printk("\tlo: 0x%08lx\n", vcpu->arch.lo);
 934
 935         cop0 = vcpu->arch.cop0;
 936         printk("\tStatus: 0x%08lx, Cause: 0x%08lx\n",
 937                kvm_read_c0_guest_status(cop0), kvm_read_c0_guest_cause(cop0));
 938
 939         printk("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
 940
 941         return 0;
 942 }
 943
 944 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 945 {
 946         int i;
 947
 948         for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
 949                 vcpu->arch.gprs[i] = regs->gpr[i];
 950         vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
 951         vcpu->arch.hi = regs->hi;
 952         vcpu->arch.lo = regs->lo;
 953         vcpu->arch.pc = regs->pc;
 954
 955         return 0;
 956 }
 957
 958 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 959 {
 960         int i;
 961
 962         for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
 963                 regs->gpr[i] = vcpu->arch.gprs[i];
 964
 965         regs->hi = vcpu->arch.hi;
 966         regs->lo = vcpu->arch.lo;
 967         regs->pc = vcpu->arch.pc;
 968
 969         return 0;
 970 }
 971
 972 void kvm_mips_comparecount_func(unsigned long data)
 973 {
 974         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
 975
 976         kvm_mips_callbacks->queue_timer_int(vcpu);
 977
 978         vcpu->arch.wait = 0;
 979         if (waitqueue_active(&vcpu->wq)) {
 980                 wake_up_interruptible(&vcpu->wq);
 981         }
 982 }
 983
 984 /*
 985  * low level hrtimer wake routine.
 986  */
 987 enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
 988 {
 989         struct kvm_vcpu *vcpu;
 990
 991         vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
 992         kvm_mips_comparecount_func((unsigned long) vcpu);
 993         hrtimer_forward_now(&vcpu->arch.comparecount_timer,
 994                             ktime_set(0, MS_TO_NS(10)));
 995         return HRTIMER_RESTART;
 996 }
 997
 998 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 999 {
1000         kvm_mips_callbacks->vcpu_init(vcpu);
1001         hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
1002                      HRTIMER_MODE_REL);
1003         vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
1004         kvm_mips_init_shadow_tlb(vcpu);
1005         return 0;
1006 }
1007
1008 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
1009 {
1010         return;
1011 }
1012
1013 int
1014 kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, struct kvm_translation *tr)
1015 {
1016         return 0;
1017 }
1018
1019 /* Initial guest state */
1020 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
1021 {
1022         return kvm_mips_callbacks->vcpu_setup(vcpu);
1023 }
1024
1025 static
1026 void kvm_mips_set_c0_status(void)
1027 {
1028         uint32_t status = read_c0_status();
1029
1030         if (cpu_has_fpu)
1031                 status |= (ST0_CU1);
1032
1033         if (cpu_has_dsp)
1034                 status |= (ST0_MX);
1035
1036         write_c0_status(status);
1037         ehb();
1038 }
1039
1040 /*
1041  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1042  */
1043 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1044 {
1045         uint32_t cause = vcpu->arch.host_cp0_cause;
1046         uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1047         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
1048         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1049         enum emulation_result er = EMULATE_DONE;
1050         int ret = RESUME_GUEST;
1051
1052         /* Set a default exit reason */
1053         run->exit_reason = KVM_EXIT_UNKNOWN;
1054         run->ready_for_interrupt_injection = 1;
1055
1056         /* Set the appropriate status bits based on host CPU features, before we hit the scheduler */
1057         kvm_mips_set_c0_status();
1058
1059         local_irq_enable();
1060
1061         kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1062                         cause, opc, run, vcpu);
1063
1064         /* Do a privilege check, if in UM most of these exit conditions end up
1065          * causing an exception to be delivered to the Guest Kernel
1066          */
1067         er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1068         if (er == EMULATE_PRIV_FAIL) {
1069                 goto skip_emul;
1070         } else if (er == EMULATE_FAIL) {
1071                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1072                 ret = RESUME_HOST;
1073                 goto skip_emul;
1074         }
1075
1076         switch (exccode) {
1077         case T_INT:
1078                 kvm_debug("[%d]T_INT @ %p\n", vcpu->vcpu_id, opc);
1079
1080                 ++vcpu->stat.int_exits;
1081                 trace_kvm_exit(vcpu, INT_EXITS);
1082
1083                 if (need_resched()) {
1084                         cond_resched();
1085                 }
1086
1087                 ret = RESUME_GUEST;
1088                 break;
1089
1090         case T_COP_UNUSABLE:
1091                 kvm_debug("T_COP_UNUSABLE: @ PC: %p\n", opc);
1092
1093                 ++vcpu->stat.cop_unusable_exits;
1094                 trace_kvm_exit(vcpu, COP_UNUSABLE_EXITS);
1095                 ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1096                 /* XXXKYMA: Might need to return to user space */
1097                 if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN) {
1098                         ret = RESUME_HOST;
1099                 }
1100                 break;
1101
1102         case T_TLB_MOD:
1103                 ++vcpu->stat.tlbmod_exits;
1104                 trace_kvm_exit(vcpu, TLBMOD_EXITS);
1105                 ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1106                 break;
1107
1108         case T_TLB_ST_MISS:
1109                 kvm_debug
1110                     ("TLB ST fault:  cause %#x, status %#lx, PC: %p, BadVaddr: %#lx\n",
1111                      cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1112                      badvaddr);
1113
1114                 ++vcpu->stat.tlbmiss_st_exits;
1115                 trace_kvm_exit(vcpu, TLBMISS_ST_EXITS);
1116                 ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1117                 break;
1118
1119         case T_TLB_LD_MISS:
1120                 kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1121                           cause, opc, badvaddr);
1122
1123                 ++vcpu->stat.tlbmiss_ld_exits;
1124                 trace_kvm_exit(vcpu, TLBMISS_LD_EXITS);
1125                 ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1126                 break;
1127
1128         case T_ADDR_ERR_ST:
1129                 ++vcpu->stat.addrerr_st_exits;
1130                 trace_kvm_exit(vcpu, ADDRERR_ST_EXITS);
1131                 ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1132                 break;
1133
1134         case T_ADDR_ERR_LD:
1135                 ++vcpu->stat.addrerr_ld_exits;
1136                 trace_kvm_exit(vcpu, ADDRERR_LD_EXITS);
1137                 ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1138                 break;
1139
1140         case T_SYSCALL:
1141                 ++vcpu->stat.syscall_exits;
1142                 trace_kvm_exit(vcpu, SYSCALL_EXITS);
1143                 ret = kvm_mips_callbacks->handle_syscall(vcpu);
1144                 break;
1145
1146         case T_RES_INST:
1147                 ++vcpu->stat.resvd_inst_exits;
1148                 trace_kvm_exit(vcpu, RESVD_INST_EXITS);
1149                 ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1150                 break;
1151
1152         case T_BREAK:
1153                 ++vcpu->stat.break_inst_exits;
1154                 trace_kvm_exit(vcpu, BREAK_INST_EXITS);
1155                 ret = kvm_mips_callbacks->handle_break(vcpu);
1156                 break;
1157
1158         default:
1159                 kvm_err
1160                     ("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#lx\n",
1161                      exccode, opc, kvm_get_inst(opc, vcpu), badvaddr,
1162                      kvm_read_c0_guest_status(vcpu->arch.cop0));
1163                 kvm_arch_vcpu_dump_regs(vcpu);
1164                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1165                 ret = RESUME_HOST;
1166                 break;
1167
1168         }
1169
1170 skip_emul:
1171         local_irq_disable();
1172
1173         if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1174                 kvm_mips_deliver_interrupts(vcpu, cause);
1175
1176         if (!(ret & RESUME_HOST)) {
1177                 /* Only check for signals if not already exiting to userspace  */
1178                 if (signal_pending(current)) {
1179                         run->exit_reason = KVM_EXIT_INTR;
1180                         ret = (-EINTR << 2) | RESUME_HOST;
1181                         ++vcpu->stat.signal_exits;
1182                         trace_kvm_exit(vcpu, SIGNAL_EXITS);
1183                 }
1184         }
1185
1186         return ret;
1187 }
1188
1189 int __init kvm_mips_init(void)
1190 {
1191         int ret;
1192
1193         ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1194
1195         if (ret)
1196                 return ret;
1197
1198         /* On MIPS, kernel modules are executed from "mapped space", which requires TLBs.
1199          * The TLB handling code is statically linked with the rest of the kernel (kvm_tlb.c)
1200          * to avoid the possibility of double faulting. The issue is that the TLB code
1201          * references routines that are part of the the KVM module,
1202          * which are only available once the module is loaded.
1203          */
1204         kvm_mips_gfn_to_pfn = gfn_to_pfn;
1205         kvm_mips_release_pfn_clean = kvm_release_pfn_clean;
1206         kvm_mips_is_error_pfn = is_error_pfn;
1207
1208         pr_info("KVM/MIPS Initialized\n");
1209         return 0;
1210 }
1211
1212 void __exit kvm_mips_exit(void)
1213 {
1214         kvm_exit();
1215
1216         kvm_mips_gfn_to_pfn = NULL;
1217         kvm_mips_release_pfn_clean = NULL;
1218         kvm_mips_is_error_pfn = NULL;
1219
1220         pr_info("KVM/MIPS unloaded\n");
1221 }
1222
1223 module_init(kvm_mips_init);
1224 module_exit(kvm_mips_exit);
1225
1226 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);