arch/mips/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 "interrupt.h"
  25 #include "commpage.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)
  35 struct kvm_stats_debugfs_item debugfs_entries[] = {
  36         { "wait",         VCPU_STAT(wait_exits),         KVM_STAT_VCPU },
  37         { "cache",        VCPU_STAT(cache_exits),        KVM_STAT_VCPU },
  38         { "signal",       VCPU_STAT(signal_exits),       KVM_STAT_VCPU },
  39         { "interrupt",    VCPU_STAT(int_exits),          KVM_STAT_VCPU },
  40         { "cop_unsuable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU },
  41         { "tlbmod",       VCPU_STAT(tlbmod_exits),       KVM_STAT_VCPU },
  42         { "tlbmiss_ld",   VCPU_STAT(tlbmiss_ld_exits),   KVM_STAT_VCPU },
  43         { "tlbmiss_st",   VCPU_STAT(tlbmiss_st_exits),   KVM_STAT_VCPU },
  44         { "addrerr_st",   VCPU_STAT(addrerr_st_exits),   KVM_STAT_VCPU },
  45         { "addrerr_ld",   VCPU_STAT(addrerr_ld_exits),   KVM_STAT_VCPU },
  46         { "syscall",      VCPU_STAT(syscall_exits),      KVM_STAT_VCPU },
  47         { "resvd_inst",   VCPU_STAT(resvd_inst_exits),   KVM_STAT_VCPU },
  48         { "break_inst",   VCPU_STAT(break_inst_exits),   KVM_STAT_VCPU },
  49         { "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU },
  50         { "halt_wakeup",  VCPU_STAT(halt_wakeup),        KVM_STAT_VCPU },
  51         {NULL}
  52 };
  53
  54 static int kvm_mips_reset_vcpu(struct kvm_vcpu *vcpu)
  55 {
  56         int i;
  57
  58         for_each_possible_cpu(i) {
  59                 vcpu->arch.guest_kernel_asid[i] = 0;
  60                 vcpu->arch.guest_user_asid[i] = 0;
  61         }
  62
  63         return 0;
  64 }
  65
  66 /*
  67  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
  68  * Config7, so we are "runnable" if interrupts are pending
  69  */
  70 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
  71 {
  72         return !!(vcpu->arch.pending_exceptions);
  73 }
  74
  75 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  76 {
  77         return 1;
  78 }
  79
  80 int kvm_arch_hardware_enable(void *garbage)
  81 {
  82         return 0;
  83 }
  84
  85 void kvm_arch_hardware_disable(void *garbage)
  86 {
  87 }
  88
  89 int kvm_arch_hardware_setup(void)
  90 {
  91         return 0;
  92 }
  93
  94 void kvm_arch_hardware_unsetup(void)
  95 {
  96 }
  97
  98 void kvm_arch_check_processor_compat(void *rtn)
  99 {
 100         *(int *)rtn = 0;
 101 }
 102
 103 static void kvm_mips_init_tlbs(struct kvm *kvm)
 104 {
 105         unsigned long wired;
 106
 107         /*
 108          * Add a wired entry to the TLB, it is used to map the commpage to
 109          * the Guest kernel
 110          */
 111         wired = read_c0_wired();
 112         write_c0_wired(wired + 1);
 113         mtc0_tlbw_hazard();
 114         kvm->arch.commpage_tlb = wired;
 115
 116         kvm_debug("[%d] commpage TLB: %d\n", smp_processor_id(),
 117                   kvm->arch.commpage_tlb);
 118 }
 119
 120 static void kvm_mips_init_vm_percpu(void *arg)
 121 {
 122         struct kvm *kvm = (struct kvm *)arg;
 123
 124         kvm_mips_init_tlbs(kvm);
 125         kvm_mips_callbacks->vm_init(kvm);
 126
 127 }
 128
 129 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 130 {
 131         if (atomic_inc_return(&kvm_mips_instance) == 1) {
 132                 kvm_debug("%s: 1st KVM instance, setup host TLB parameters\n",
 133                           __func__);
 134                 on_each_cpu(kvm_mips_init_vm_percpu, kvm, 1);
 135         }
 136
 137         return 0;
 138 }
 139
 140 void kvm_mips_free_vcpus(struct kvm *kvm)
 141 {
 142         unsigned int i;
 143         struct kvm_vcpu *vcpu;
 144
 145         /* Put the pages we reserved for the guest pmap */
 146         for (i = 0; i < kvm->arch.guest_pmap_npages; i++) {
 147                 if (kvm->arch.guest_pmap[i] != KVM_INVALID_PAGE)
 148                         kvm_mips_release_pfn_clean(kvm->arch.guest_pmap[i]);
 149         }
 150         kfree(kvm->arch.guest_pmap);
 151
 152         kvm_for_each_vcpu(i, vcpu, kvm) {
 153                 kvm_arch_vcpu_free(vcpu);
 154         }
 155
 156         mutex_lock(&kvm->lock);
 157
 158         for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
 159                 kvm->vcpus[i] = NULL;
 160
 161         atomic_set(&kvm->online_vcpus, 0);
 162
 163         mutex_unlock(&kvm->lock);
 164 }
 165
 166 void kvm_arch_sync_events(struct kvm *kvm)
 167 {
 168 }
 169
 170 static void kvm_mips_uninit_tlbs(void *arg)
 171 {
 172         /* Restore wired count */
 173         write_c0_wired(0);
 174         mtc0_tlbw_hazard();
 175         /* Clear out all the TLBs */
 176         kvm_local_flush_tlb_all();
 177 }
 178
 179 void kvm_arch_destroy_vm(struct kvm *kvm)
 180 {
 181         kvm_mips_free_vcpus(kvm);
 182
 183         /* If this is the last instance, restore wired count */
 184         if (atomic_dec_return(&kvm_mips_instance) == 0) {
 185                 kvm_debug("%s: last KVM instance, restoring TLB parameters\n",
 186                           __func__);
 187                 on_each_cpu(kvm_mips_uninit_tlbs, NULL, 1);
 188         }
 189 }
 190
 191 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
 192                         unsigned long arg)
 193 {
 194         return -ENOIOCTLCMD;
 195 }
 196
 197 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
 198                            struct kvm_memory_slot *dont)
 199 {
 200 }
 201
 202 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
 203                             unsigned long npages)
 204 {
 205         return 0;
 206 }
 207
 208 void kvm_arch_memslots_updated(struct kvm *kvm)
 209 {
 210 }
 211
 212 int kvm_arch_prepare_memory_region(struct kvm *kvm,
 213                                    struct kvm_memory_slot *memslot,
 214                                    struct kvm_userspace_memory_region *mem,
 215                                    enum kvm_mr_change change)
 216 {
 217         return 0;
 218 }
 219
 220 void kvm_arch_commit_memory_region(struct kvm *kvm,
 221                                    struct kvm_userspace_memory_region *mem,
 222                                    const struct kvm_memory_slot *old,
 223                                    enum kvm_mr_change change)
 224 {
 225         unsigned long npages = 0;
 226         int i;
 227
 228         kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
 229                   __func__, kvm, mem->slot, mem->guest_phys_addr,
 230                   mem->memory_size, mem->userspace_addr);
 231
 232         /* Setup Guest PMAP table */
 233         if (!kvm->arch.guest_pmap) {
 234                 if (mem->slot == 0)
 235                         npages = mem->memory_size >> PAGE_SHIFT;
 236
 237                 if (npages) {
 238                         kvm->arch.guest_pmap_npages = npages;
 239                         kvm->arch.guest_pmap =
 240                             kzalloc(npages * sizeof(unsigned long), GFP_KERNEL);
 241
 242                         if (!kvm->arch.guest_pmap) {
 243                                 kvm_err("Failed to allocate guest PMAP");
 244                                 return;
 245                         }
 246
 247                         kvm_debug("Allocated space for Guest PMAP Table (%ld pages) @ %p\n",
 248                                   npages, kvm->arch.guest_pmap);
 249
 250                         /* Now setup the page table */
 251                         for (i = 0; i < npages; i++)
 252                                 kvm->arch.guest_pmap[i] = KVM_INVALID_PAGE;
 253                 }
 254         }
 255 }
 256
 257 void kvm_arch_flush_shadow_all(struct kvm *kvm)
 258 {
 259 }
 260
 261 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
 262                                    struct kvm_memory_slot *slot)
 263 {
 264 }
 265
 266 void kvm_arch_flush_shadow(struct kvm *kvm)
 267 {
 268 }
 269
 270 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 271 {
 272         int err, size, offset;
 273         void *gebase;
 274         int i;
 275
 276         struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
 277
 278         if (!vcpu) {
 279                 err = -ENOMEM;
 280                 goto out;
 281         }
 282
 283         err = kvm_vcpu_init(vcpu, kvm, id);
 284
 285         if (err)
 286                 goto out_free_cpu;
 287
 288         kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
 289
 290         /*
 291          * Allocate space for host mode exception handlers that handle
 292          * guest mode exits
 293          */
 294         if (cpu_has_veic || cpu_has_vint)
 295                 size = 0x200 + VECTORSPACING * 64;
 296         else
 297                 size = 0x4000;
 298
 299         /* Save Linux EBASE */
 300         vcpu->arch.host_ebase = (void *)read_c0_ebase();
 301
 302         gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
 303
 304         if (!gebase) {
 305                 err = -ENOMEM;
 306                 goto out_free_cpu;
 307         }
 308         kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
 309                   ALIGN(size, PAGE_SIZE), gebase);
 310
 311         /* Save new ebase */
 312         vcpu->arch.guest_ebase = gebase;
 313
 314         /* Copy L1 Guest Exception handler to correct offset */
 315
 316         /* TLB Refill, EXL = 0 */
 317         memcpy(gebase, mips32_exception,
 318                mips32_exceptionEnd - mips32_exception);
 319
 320         /* General Exception Entry point */
 321         memcpy(gebase + 0x180, mips32_exception,
 322                mips32_exceptionEnd - mips32_exception);
 323
 324         /* For vectored interrupts poke the exception code @ all offsets 0-7 */
 325         for (i = 0; i < 8; i++) {
 326                 kvm_debug("L1 Vectored handler @ %p\n",
 327                           gebase + 0x200 + (i * VECTORSPACING));
 328                 memcpy(gebase + 0x200 + (i * VECTORSPACING), mips32_exception,
 329                        mips32_exceptionEnd - mips32_exception);
 330         }
 331
 332         /* General handler, relocate to unmapped space for sanity's sake */
 333         offset = 0x2000;
 334         kvm_debug("Installing KVM Exception handlers @ %p, %#x bytes\n",
 335                   gebase + offset,
 336                   mips32_GuestExceptionEnd - mips32_GuestException);
 337
 338         memcpy(gebase + offset, mips32_GuestException,
 339                mips32_GuestExceptionEnd - mips32_GuestException);
 340
 341         /* Invalidate the icache for these ranges */
 342         local_flush_icache_range((unsigned long)gebase,
 343                                 (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
 344
 345         /*
 346          * Allocate comm page for guest kernel, a TLB will be reserved for
 347          * mapping GVA @ 0xFFFF8000 to this page
 348          */
 349         vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
 350
 351         if (!vcpu->arch.kseg0_commpage) {
 352                 err = -ENOMEM;
 353                 goto out_free_gebase;
 354         }
 355
 356         kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
 357         kvm_mips_commpage_init(vcpu);
 358
 359         /* Init */
 360         vcpu->arch.last_sched_cpu = -1;
 361
 362         /* Start off the timer */
 363         kvm_mips_init_count(vcpu);
 364
 365         return vcpu;
 366
 367 out_free_gebase:
 368         kfree(gebase);
 369
 370 out_free_cpu:
 371         kfree(vcpu);
 372
 373 out:
 374         return ERR_PTR(err);
 375 }
 376
 377 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 378 {
 379         hrtimer_cancel(&vcpu->arch.comparecount_timer);
 380
 381         kvm_vcpu_uninit(vcpu);
 382
 383         kvm_mips_dump_stats(vcpu);
 384
 385         kfree(vcpu->arch.guest_ebase);
 386         kfree(vcpu->arch.kseg0_commpage);
 387 }
 388
 389 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 390 {
 391         kvm_arch_vcpu_free(vcpu);
 392 }
 393
 394 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 395                                         struct kvm_guest_debug *dbg)
 396 {
 397         return -ENOIOCTLCMD;
 398 }
 399
 400 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 401 {
 402         int r = 0;
 403         sigset_t sigsaved;
 404
 405         if (vcpu->sigset_active)
 406                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 407
 408         if (vcpu->mmio_needed) {
 409                 if (!vcpu->mmio_is_write)
 410                         kvm_mips_complete_mmio_load(vcpu, run);
 411                 vcpu->mmio_needed = 0;
 412         }
 413
 414         local_irq_disable();
 415         /* Check if we have any exceptions/interrupts pending */
 416         kvm_mips_deliver_interrupts(vcpu,
 417                                     kvm_read_c0_guest_cause(vcpu->arch.cop0));
 418
 419         kvm_guest_enter();
 420
 421         r = __kvm_mips_vcpu_run(run, vcpu);
 422
 423         kvm_guest_exit();
 424         local_irq_enable();
 425
 426         if (vcpu->sigset_active)
 427                 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
 428
 429         return r;
 430 }
 431
 432 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
 433                              struct kvm_mips_interrupt *irq)
 434 {
 435         int intr = (int)irq->irq;
 436         struct kvm_vcpu *dvcpu = NULL;
 437
 438         if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
 439                 kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
 440                           (int)intr);
 441
 442         if (irq->cpu == -1)
 443                 dvcpu = vcpu;
 444         else
 445                 dvcpu = vcpu->kvm->vcpus[irq->cpu];
 446
 447         if (intr == 2 || intr == 3 || intr == 4) {
 448                 kvm_mips_callbacks->queue_io_int(dvcpu, irq);
 449
 450         } else if (intr == -2 || intr == -3 || intr == -4) {
 451                 kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
 452         } else {
 453                 kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
 454                         irq->cpu, irq->irq);
 455                 return -EINVAL;
 456         }
 457
 458         dvcpu->arch.wait = 0;
 459
 460         if (waitqueue_active(&dvcpu->wq))
 461                 wake_up_interruptible(&dvcpu->wq);
 462
 463         return 0;
 464 }
 465
 466 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 467                                     struct kvm_mp_state *mp_state)
 468 {
 469         return -ENOIOCTLCMD;
 470 }
 471
 472 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 473                                     struct kvm_mp_state *mp_state)
 474 {
 475         return -ENOIOCTLCMD;
 476 }
 477
 478 static u64 kvm_mips_get_one_regs[] = {
 479         KVM_REG_MIPS_R0,
 480         KVM_REG_MIPS_R1,
 481         KVM_REG_MIPS_R2,
 482         KVM_REG_MIPS_R3,
 483         KVM_REG_MIPS_R4,
 484         KVM_REG_MIPS_R5,
 485         KVM_REG_MIPS_R6,
 486         KVM_REG_MIPS_R7,
 487         KVM_REG_MIPS_R8,
 488         KVM_REG_MIPS_R9,
 489         KVM_REG_MIPS_R10,
 490         KVM_REG_MIPS_R11,
 491         KVM_REG_MIPS_R12,
 492         KVM_REG_MIPS_R13,
 493         KVM_REG_MIPS_R14,
 494         KVM_REG_MIPS_R15,
 495         KVM_REG_MIPS_R16,
 496         KVM_REG_MIPS_R17,
 497         KVM_REG_MIPS_R18,
 498         KVM_REG_MIPS_R19,
 499         KVM_REG_MIPS_R20,
 500         KVM_REG_MIPS_R21,
 501         KVM_REG_MIPS_R22,
 502         KVM_REG_MIPS_R23,
 503         KVM_REG_MIPS_R24,
 504         KVM_REG_MIPS_R25,
 505         KVM_REG_MIPS_R26,
 506         KVM_REG_MIPS_R27,
 507         KVM_REG_MIPS_R28,
 508         KVM_REG_MIPS_R29,
 509         KVM_REG_MIPS_R30,
 510         KVM_REG_MIPS_R31,
 511
 512         KVM_REG_MIPS_HI,
 513         KVM_REG_MIPS_LO,
 514         KVM_REG_MIPS_PC,
 515
 516         KVM_REG_MIPS_CP0_INDEX,
 517         KVM_REG_MIPS_CP0_CONTEXT,
 518         KVM_REG_MIPS_CP0_USERLOCAL,
 519         KVM_REG_MIPS_CP0_PAGEMASK,
 520         KVM_REG_MIPS_CP0_WIRED,
 521         KVM_REG_MIPS_CP0_HWRENA,
 522         KVM_REG_MIPS_CP0_BADVADDR,
 523         KVM_REG_MIPS_CP0_COUNT,
 524         KVM_REG_MIPS_CP0_ENTRYHI,
 525         KVM_REG_MIPS_CP0_COMPARE,
 526         KVM_REG_MIPS_CP0_STATUS,
 527         KVM_REG_MIPS_CP0_CAUSE,
 528         KVM_REG_MIPS_CP0_EPC,
 529         KVM_REG_MIPS_CP0_CONFIG,
 530         KVM_REG_MIPS_CP0_CONFIG1,
 531         KVM_REG_MIPS_CP0_CONFIG2,
 532         KVM_REG_MIPS_CP0_CONFIG3,
 533         KVM_REG_MIPS_CP0_CONFIG7,
 534         KVM_REG_MIPS_CP0_ERROREPC,
 535
 536         KVM_REG_MIPS_COUNT_CTL,
 537         KVM_REG_MIPS_COUNT_RESUME,
 538         KVM_REG_MIPS_COUNT_HZ,
 539 };
 540
 541 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
 542                             const struct kvm_one_reg *reg)
 543 {
 544         struct mips_coproc *cop0 = vcpu->arch.cop0;
 545         int ret;
 546         s64 v;
 547
 548         switch (reg->id) {
 549         case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
 550                 v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
 551                 break;
 552         case KVM_REG_MIPS_HI:
 553                 v = (long)vcpu->arch.hi;
 554                 break;
 555         case KVM_REG_MIPS_LO:
 556                 v = (long)vcpu->arch.lo;
 557                 break;
 558         case KVM_REG_MIPS_PC:
 559                 v = (long)vcpu->arch.pc;
 560                 break;
 561
 562         case KVM_REG_MIPS_CP0_INDEX:
 563                 v = (long)kvm_read_c0_guest_index(cop0);
 564                 break;
 565         case KVM_REG_MIPS_CP0_CONTEXT:
 566                 v = (long)kvm_read_c0_guest_context(cop0);
 567                 break;
 568         case KVM_REG_MIPS_CP0_USERLOCAL:
 569                 v = (long)kvm_read_c0_guest_userlocal(cop0);
 570                 break;
 571         case KVM_REG_MIPS_CP0_PAGEMASK:
 572                 v = (long)kvm_read_c0_guest_pagemask(cop0);
 573                 break;
 574         case KVM_REG_MIPS_CP0_WIRED:
 575                 v = (long)kvm_read_c0_guest_wired(cop0);
 576                 break;
 577         case KVM_REG_MIPS_CP0_HWRENA:
 578                 v = (long)kvm_read_c0_guest_hwrena(cop0);
 579                 break;
 580         case KVM_REG_MIPS_CP0_BADVADDR:
 581                 v = (long)kvm_read_c0_guest_badvaddr(cop0);
 582                 break;
 583         case KVM_REG_MIPS_CP0_ENTRYHI:
 584                 v = (long)kvm_read_c0_guest_entryhi(cop0);
 585                 break;
 586         case KVM_REG_MIPS_CP0_COMPARE:
 587                 v = (long)kvm_read_c0_guest_compare(cop0);
 588                 break;
 589         case KVM_REG_MIPS_CP0_STATUS:
 590                 v = (long)kvm_read_c0_guest_status(cop0);
 591                 break;
 592         case KVM_REG_MIPS_CP0_CAUSE:
 593                 v = (long)kvm_read_c0_guest_cause(cop0);
 594                 break;
 595         case KVM_REG_MIPS_CP0_EPC:
 596                 v = (long)kvm_read_c0_guest_epc(cop0);
 597                 break;
 598         case KVM_REG_MIPS_CP0_ERROREPC:
 599                 v = (long)kvm_read_c0_guest_errorepc(cop0);
 600                 break;
 601         case KVM_REG_MIPS_CP0_CONFIG:
 602                 v = (long)kvm_read_c0_guest_config(cop0);
 603                 break;
 604         case KVM_REG_MIPS_CP0_CONFIG1:
 605                 v = (long)kvm_read_c0_guest_config1(cop0);
 606                 break;
 607         case KVM_REG_MIPS_CP0_CONFIG2:
 608                 v = (long)kvm_read_c0_guest_config2(cop0);
 609                 break;
 610         case KVM_REG_MIPS_CP0_CONFIG3:
 611                 v = (long)kvm_read_c0_guest_config3(cop0);
 612                 break;
 613         case KVM_REG_MIPS_CP0_CONFIG7:
 614                 v = (long)kvm_read_c0_guest_config7(cop0);
 615                 break;
 616         /* registers to be handled specially */
 617         case KVM_REG_MIPS_CP0_COUNT:
 618         case KVM_REG_MIPS_COUNT_CTL:
 619         case KVM_REG_MIPS_COUNT_RESUME:
 620         case KVM_REG_MIPS_COUNT_HZ:
 621                 ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
 622                 if (ret)
 623                         return ret;
 624                 break;
 625         default:
 626                 return -EINVAL;
 627         }
 628         if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
 629                 u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
 630
 631                 return put_user(v, uaddr64);
 632         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
 633                 u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
 634                 u32 v32 = (u32)v;
 635
 636                 return put_user(v32, uaddr32);
 637         } else {
 638                 return -EINVAL;
 639         }
 640 }
 641
 642 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
 643                             const struct kvm_one_reg *reg)
 644 {
 645         struct mips_coproc *cop0 = vcpu->arch.cop0;
 646         u64 v;
 647
 648         if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
 649                 u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
 650
 651                 if (get_user(v, uaddr64) != 0)
 652                         return -EFAULT;
 653         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
 654                 u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
 655                 s32 v32;
 656
 657                 if (get_user(v32, uaddr32) != 0)
 658                         return -EFAULT;
 659                 v = (s64)v32;
 660         } else {
 661                 return -EINVAL;
 662         }
 663
 664         switch (reg->id) {
 665         case KVM_REG_MIPS_R0:
 666                 /* Silently ignore requests to set $0 */
 667                 break;
 668         case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
 669                 vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
 670                 break;
 671         case KVM_REG_MIPS_HI:
 672                 vcpu->arch.hi = v;
 673                 break;
 674         case KVM_REG_MIPS_LO:
 675                 vcpu->arch.lo = v;
 676                 break;
 677         case KVM_REG_MIPS_PC:
 678                 vcpu->arch.pc = v;
 679                 break;
 680
 681         case KVM_REG_MIPS_CP0_INDEX:
 682                 kvm_write_c0_guest_index(cop0, v);
 683                 break;
 684         case KVM_REG_MIPS_CP0_CONTEXT:
 685                 kvm_write_c0_guest_context(cop0, v);
 686                 break;
 687         case KVM_REG_MIPS_CP0_USERLOCAL:
 688                 kvm_write_c0_guest_userlocal(cop0, v);
 689                 break;
 690         case KVM_REG_MIPS_CP0_PAGEMASK:
 691                 kvm_write_c0_guest_pagemask(cop0, v);
 692                 break;
 693         case KVM_REG_MIPS_CP0_WIRED:
 694                 kvm_write_c0_guest_wired(cop0, v);
 695                 break;
 696         case KVM_REG_MIPS_CP0_HWRENA:
 697                 kvm_write_c0_guest_hwrena(cop0, v);
 698                 break;
 699         case KVM_REG_MIPS_CP0_BADVADDR:
 700                 kvm_write_c0_guest_badvaddr(cop0, v);
 701                 break;
 702         case KVM_REG_MIPS_CP0_ENTRYHI:
 703                 kvm_write_c0_guest_entryhi(cop0, v);
 704                 break;
 705         case KVM_REG_MIPS_CP0_STATUS:
 706                 kvm_write_c0_guest_status(cop0, v);
 707                 break;
 708         case KVM_REG_MIPS_CP0_EPC:
 709                 kvm_write_c0_guest_epc(cop0, v);
 710                 break;
 711         case KVM_REG_MIPS_CP0_ERROREPC:
 712                 kvm_write_c0_guest_errorepc(cop0, v);
 713                 break;
 714         /* registers to be handled specially */
 715         case KVM_REG_MIPS_CP0_COUNT:
 716         case KVM_REG_MIPS_CP0_COMPARE:
 717         case KVM_REG_MIPS_CP0_CAUSE:
 718         case KVM_REG_MIPS_COUNT_CTL:
 719         case KVM_REG_MIPS_COUNT_RESUME:
 720         case KVM_REG_MIPS_COUNT_HZ:
 721                 return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
 722         default:
 723                 return -EINVAL;
 724         }
 725         return 0;
 726 }
 727
 728 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
 729                          unsigned long arg)
 730 {
 731         struct kvm_vcpu *vcpu = filp->private_data;
 732         void __user *argp = (void __user *)arg;
 733         long r;
 734
 735         switch (ioctl) {
 736         case KVM_SET_ONE_REG:
 737         case KVM_GET_ONE_REG: {
 738                 struct kvm_one_reg reg;
 739
 740                 if (copy_from_user(&reg, argp, sizeof(reg)))
 741                         return -EFAULT;
 742                 if (ioctl == KVM_SET_ONE_REG)
 743                         return kvm_mips_set_reg(vcpu, &reg);
 744                 else
 745                         return kvm_mips_get_reg(vcpu, &reg);
 746         }
 747         case KVM_GET_REG_LIST: {
 748                 struct kvm_reg_list __user *user_list = argp;
 749                 u64 __user *reg_dest;
 750                 struct kvm_reg_list reg_list;
 751                 unsigned n;
 752
 753                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
 754                         return -EFAULT;
 755                 n = reg_list.n;
 756                 reg_list.n = ARRAY_SIZE(kvm_mips_get_one_regs);
 757                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
 758                         return -EFAULT;
 759                 if (n < reg_list.n)
 760                         return -E2BIG;
 761                 reg_dest = user_list->reg;
 762                 if (copy_to_user(reg_dest, kvm_mips_get_one_regs,
 763                                  sizeof(kvm_mips_get_one_regs)))
 764                         return -EFAULT;
 765                 return 0;
 766         }
 767         case KVM_NMI:
 768                 /* Treat the NMI as a CPU reset */
 769                 r = kvm_mips_reset_vcpu(vcpu);
 770                 break;
 771         case KVM_INTERRUPT:
 772                 {
 773                         struct kvm_mips_interrupt irq;
 774
 775                         r = -EFAULT;
 776                         if (copy_from_user(&irq, argp, sizeof(irq)))
 777                                 goto out;
 778
 779                         kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
 780                                   irq.irq);
 781
 782                         r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
 783                         break;
 784                 }
 785         default:
 786                 r = -ENOIOCTLCMD;
 787         }
 788
 789 out:
 790         return r;
 791 }
 792
 793 /* Get (and clear) the dirty memory log for a memory slot. */
 794 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 795 {
 796         struct kvm_memory_slot *memslot;
 797         unsigned long ga, ga_end;
 798         int is_dirty = 0;
 799         int r;
 800         unsigned long n;
 801
 802         mutex_lock(&kvm->slots_lock);
 803
 804         r = kvm_get_dirty_log(kvm, log, &is_dirty);
 805         if (r)
 806                 goto out;
 807
 808         /* If nothing is dirty, don't bother messing with page tables. */
 809         if (is_dirty) {
 810                 memslot = &kvm->memslots->memslots[log->slot];
 811
 812                 ga = memslot->base_gfn << PAGE_SHIFT;
 813                 ga_end = ga + (memslot->npages << PAGE_SHIFT);
 814
 815                 kvm_info("%s: dirty, ga: %#lx, ga_end %#lx\n", __func__, ga,
 816                          ga_end);
 817
 818                 n = kvm_dirty_bitmap_bytes(memslot);
 819                 memset(memslot->dirty_bitmap, 0, n);
 820         }
 821
 822         r = 0;
 823 out:
 824         mutex_unlock(&kvm->slots_lock);
 825         return r;
 826
 827 }
 828
 829 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 830 {
 831         long r;
 832
 833         switch (ioctl) {
 834         default:
 835                 r = -ENOIOCTLCMD;
 836         }
 837
 838         return r;
 839 }
 840
 841 int kvm_arch_init(void *opaque)
 842 {
 843         if (kvm_mips_callbacks) {
 844                 kvm_err("kvm: module already exists\n");
 845                 return -EEXIST;
 846         }
 847
 848         return kvm_mips_emulation_init(&kvm_mips_callbacks);
 849 }
 850
 851 void kvm_arch_exit(void)
 852 {
 853         kvm_mips_callbacks = NULL;
 854 }
 855
 856 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 857                                   struct kvm_sregs *sregs)
 858 {
 859         return -ENOIOCTLCMD;
 860 }
 861
 862 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 863                                   struct kvm_sregs *sregs)
 864 {
 865         return -ENOIOCTLCMD;
 866 }
 867
 868 int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 869 {
 870         return 0;
 871 }
 872
 873 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 874 {
 875         return -ENOIOCTLCMD;
 876 }
 877
 878 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 879 {
 880         return -ENOIOCTLCMD;
 881 }
 882
 883 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 884 {
 885         return VM_FAULT_SIGBUS;
 886 }
 887
 888 int kvm_dev_ioctl_check_extension(long ext)
 889 {
 890         int r;
 891
 892         switch (ext) {
 893         case KVM_CAP_ONE_REG:
 894                 r = 1;
 895                 break;
 896         case KVM_CAP_COALESCED_MMIO:
 897                 r = KVM_COALESCED_MMIO_PAGE_OFFSET;
 898                 break;
 899         default:
 900                 r = 0;
 901                 break;
 902         }
 903         return r;
 904 }
 905
 906 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 907 {
 908         return kvm_mips_pending_timer(vcpu);
 909 }
 910
 911 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
 912 {
 913         int i;
 914         struct mips_coproc *cop0;
 915
 916         if (!vcpu)
 917                 return -1;
 918
 919         kvm_debug("VCPU Register Dump:\n");
 920         kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
 921         kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
 922
 923         for (i = 0; i < 32; i += 4) {
 924                 kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
 925                        vcpu->arch.gprs[i],
 926                        vcpu->arch.gprs[i + 1],
 927                        vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
 928         }
 929         kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
 930         kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
 931
 932         cop0 = vcpu->arch.cop0;
 933         kvm_debug("\tStatus: 0x%08lx, Cause: 0x%08lx\n",
 934                   kvm_read_c0_guest_status(cop0),
 935                   kvm_read_c0_guest_cause(cop0));
 936
 937         kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
 938
 939         return 0;
 940 }
 941
 942 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 943 {
 944         int i;
 945
 946         for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
 947                 vcpu->arch.gprs[i] = regs->gpr[i];
 948         vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
 949         vcpu->arch.hi = regs->hi;
 950         vcpu->arch.lo = regs->lo;
 951         vcpu->arch.pc = regs->pc;
 952
 953         return 0;
 954 }
 955
 956 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 957 {
 958         int i;
 959
 960         for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
 961                 regs->gpr[i] = vcpu->arch.gprs[i];
 962
 963         regs->hi = vcpu->arch.hi;
 964         regs->lo = vcpu->arch.lo;
 965         regs->pc = vcpu->arch.pc;
 966
 967         return 0;
 968 }
 969
 970 static void kvm_mips_comparecount_func(unsigned long data)
 971 {
 972         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
 973
 974         kvm_mips_callbacks->queue_timer_int(vcpu);
 975
 976         vcpu->arch.wait = 0;
 977         if (waitqueue_active(&vcpu->wq))
 978                 wake_up_interruptible(&vcpu->wq);
 979 }
 980
 981 /* low level hrtimer wake routine */
 982 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
 983 {
 984         struct kvm_vcpu *vcpu;
 985
 986         vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
 987         kvm_mips_comparecount_func((unsigned long) vcpu);
 988         return kvm_mips_count_timeout(vcpu);
 989 }
 990
 991 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 992 {
 993         kvm_mips_callbacks->vcpu_init(vcpu);
 994         hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
 995                      HRTIMER_MODE_REL);
 996         vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
 997         return 0;
 998 }
 999
1000 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
1001 {
1002 }
1003
1004 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1005                                   struct kvm_translation *tr)
1006 {
1007         return 0;
1008 }
1009
1010 /* Initial guest state */
1011 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
1012 {
1013         return kvm_mips_callbacks->vcpu_setup(vcpu);
1014 }
1015
1016 static void kvm_mips_set_c0_status(void)
1017 {
1018         uint32_t status = read_c0_status();
1019
1020         if (cpu_has_fpu)
1021                 status |= (ST0_CU1);
1022
1023         if (cpu_has_dsp)
1024                 status |= (ST0_MX);
1025
1026         write_c0_status(status);
1027         ehb();
1028 }
1029
1030 /*
1031  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1032  */
1033 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1034 {
1035         uint32_t cause = vcpu->arch.host_cp0_cause;
1036         uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1037         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
1038         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1039         enum emulation_result er = EMULATE_DONE;
1040         int ret = RESUME_GUEST;
1041
1042         /* Set a default exit reason */
1043         run->exit_reason = KVM_EXIT_UNKNOWN;
1044         run->ready_for_interrupt_injection = 1;
1045
1046         /*
1047          * Set the appropriate status bits based on host CPU features,
1048          * before we hit the scheduler
1049          */
1050         kvm_mips_set_c0_status();
1051
1052         local_irq_enable();
1053
1054         kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1055                         cause, opc, run, vcpu);
1056
1057         /*
1058          * Do a privilege check, if in UM most of these exit conditions end up
1059          * causing an exception to be delivered to the Guest Kernel
1060          */
1061         er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1062         if (er == EMULATE_PRIV_FAIL) {
1063                 goto skip_emul;
1064         } else if (er == EMULATE_FAIL) {
1065                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1066                 ret = RESUME_HOST;
1067                 goto skip_emul;
1068         }
1069
1070         switch (exccode) {
1071         case T_INT:
1072                 kvm_debug("[%d]T_INT @ %p\n", vcpu->vcpu_id, opc);
1073
1074                 ++vcpu->stat.int_exits;
1075                 trace_kvm_exit(vcpu, INT_EXITS);
1076
1077                 if (need_resched())
1078                         cond_resched();
1079
1080                 ret = RESUME_GUEST;
1081                 break;
1082
1083         case T_COP_UNUSABLE:
1084                 kvm_debug("T_COP_UNUSABLE: @ PC: %p\n", opc);
1085
1086                 ++vcpu->stat.cop_unusable_exits;
1087                 trace_kvm_exit(vcpu, COP_UNUSABLE_EXITS);
1088                 ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1089                 /* XXXKYMA: Might need to return to user space */
1090                 if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1091                         ret = RESUME_HOST;
1092                 break;
1093
1094         case T_TLB_MOD:
1095                 ++vcpu->stat.tlbmod_exits;
1096                 trace_kvm_exit(vcpu, TLBMOD_EXITS);
1097                 ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1098                 break;
1099
1100         case T_TLB_ST_MISS:
1101                 kvm_debug("TLB ST fault:  cause %#x, status %#lx, PC: %p, BadVaddr: %#lx\n",
1102                           cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1103                           badvaddr);
1104
1105                 ++vcpu->stat.tlbmiss_st_exits;
1106                 trace_kvm_exit(vcpu, TLBMISS_ST_EXITS);
1107                 ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1108                 break;
1109
1110         case T_TLB_LD_MISS:
1111                 kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1112                           cause, opc, badvaddr);
1113
1114                 ++vcpu->stat.tlbmiss_ld_exits;
1115                 trace_kvm_exit(vcpu, TLBMISS_LD_EXITS);
1116                 ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1117                 break;
1118
1119         case T_ADDR_ERR_ST:
1120                 ++vcpu->stat.addrerr_st_exits;
1121                 trace_kvm_exit(vcpu, ADDRERR_ST_EXITS);
1122                 ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1123                 break;
1124
1125         case T_ADDR_ERR_LD:
1126                 ++vcpu->stat.addrerr_ld_exits;
1127                 trace_kvm_exit(vcpu, ADDRERR_LD_EXITS);
1128                 ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1129                 break;
1130
1131         case T_SYSCALL:
1132                 ++vcpu->stat.syscall_exits;
1133                 trace_kvm_exit(vcpu, SYSCALL_EXITS);
1134                 ret = kvm_mips_callbacks->handle_syscall(vcpu);
1135                 break;
1136
1137         case T_RES_INST:
1138                 ++vcpu->stat.resvd_inst_exits;
1139                 trace_kvm_exit(vcpu, RESVD_INST_EXITS);
1140                 ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1141                 break;
1142
1143         case T_BREAK:
1144                 ++vcpu->stat.break_inst_exits;
1145                 trace_kvm_exit(vcpu, BREAK_INST_EXITS);
1146                 ret = kvm_mips_callbacks->handle_break(vcpu);
1147                 break;
1148
1149         default:
1150                 kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#lx\n",
1151                         exccode, opc, kvm_get_inst(opc, vcpu), badvaddr,
1152                         kvm_read_c0_guest_status(vcpu->arch.cop0));
1153                 kvm_arch_vcpu_dump_regs(vcpu);
1154                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1155                 ret = RESUME_HOST;
1156                 break;
1157
1158         }
1159
1160 skip_emul:
1161         local_irq_disable();
1162
1163         if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1164                 kvm_mips_deliver_interrupts(vcpu, cause);
1165
1166         if (!(ret & RESUME_HOST)) {
1167                 /* Only check for signals if not already exiting to userspace */
1168                 if (signal_pending(current)) {
1169                         run->exit_reason = KVM_EXIT_INTR;
1170                         ret = (-EINTR << 2) | RESUME_HOST;
1171                         ++vcpu->stat.signal_exits;
1172                         trace_kvm_exit(vcpu, SIGNAL_EXITS);
1173                 }
1174         }
1175
1176         return ret;
1177 }
1178
1179 int __init kvm_mips_init(void)
1180 {
1181         int ret;
1182
1183         ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1184
1185         if (ret)
1186                 return ret;
1187
1188         /*
1189          * On MIPS, kernel modules are executed from "mapped space", which
1190          * requires TLBs. The TLB handling code is statically linked with
1191          * the rest of the kernel (tlb.c) to avoid the possibility of
1192          * double faulting. The issue is that the TLB code references
1193          * routines that are part of the the KVM module, which are only
1194          * available once the module is loaded.
1195          */
1196         kvm_mips_gfn_to_pfn = gfn_to_pfn;
1197         kvm_mips_release_pfn_clean = kvm_release_pfn_clean;
1198         kvm_mips_is_error_pfn = is_error_pfn;
1199
1200         pr_info("KVM/MIPS Initialized\n");
1201         return 0;
1202 }
1203
1204 void __exit kvm_mips_exit(void)
1205 {
1206         kvm_exit();
1207
1208         kvm_mips_gfn_to_pfn = NULL;
1209         kvm_mips_release_pfn_clean = NULL;
1210         kvm_mips_is_error_pfn = NULL;
1211
1212         pr_info("KVM/MIPS unloaded\n");
1213 }
1214
1215 module_init(kvm_mips_init);
1216 module_exit(kvm_mips_exit);
1217
1218 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);