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 <[email protected]>
  10  */
  11
  12 #include <linux/bitops.h>
  13 #include <linux/errno.h>
  14 #include <linux/err.h>
  15 #include <linux/kdebug.h>
  16 #include <linux/module.h>
  17 #include <linux/uaccess.h>
  18 #include <linux/vmalloc.h>
  19 #include <linux/sched/signal.h>
  20 #include <linux/fs.h>
  21 #include <linux/memblock.h>
  22
  23 #include <asm/fpu.h>
  24 #include <asm/page.h>
  25 #include <asm/cacheflush.h>
  26 #include <asm/mmu_context.h>
  27 #include <asm/pgalloc.h>
  28 #include <asm/pgtable.h>
  29
  30 #include <linux/kvm_host.h>
  31
  32 #include "interrupt.h"
  33 #include "commpage.h"
  34
  35 #define CREATE_TRACE_POINTS
  36 #include "trace.h"
  37
  38 #ifndef VECTORSPACING
  39 #define VECTORSPACING 0x100     /* for EI/VI mode */
  40 #endif
  41
  42 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x)
  43 struct kvm_stats_debugfs_item debugfs_entries[] = {
  44         { "wait",         VCPU_STAT(wait_exits),         KVM_STAT_VCPU },
  45         { "cache",        VCPU_STAT(cache_exits),        KVM_STAT_VCPU },
  46         { "signal",       VCPU_STAT(signal_exits),       KVM_STAT_VCPU },
  47         { "interrupt",    VCPU_STAT(int_exits),          KVM_STAT_VCPU },
  48         { "cop_unusable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU },
  49         { "tlbmod",       VCPU_STAT(tlbmod_exits),       KVM_STAT_VCPU },
  50         { "tlbmiss_ld",   VCPU_STAT(tlbmiss_ld_exits),   KVM_STAT_VCPU },
  51         { "tlbmiss_st",   VCPU_STAT(tlbmiss_st_exits),   KVM_STAT_VCPU },
  52         { "addrerr_st",   VCPU_STAT(addrerr_st_exits),   KVM_STAT_VCPU },
  53         { "addrerr_ld",   VCPU_STAT(addrerr_ld_exits),   KVM_STAT_VCPU },
  54         { "syscall",      VCPU_STAT(syscall_exits),      KVM_STAT_VCPU },
  55         { "resvd_inst",   VCPU_STAT(resvd_inst_exits),   KVM_STAT_VCPU },
  56         { "break_inst",   VCPU_STAT(break_inst_exits),   KVM_STAT_VCPU },
  57         { "trap_inst",    VCPU_STAT(trap_inst_exits),    KVM_STAT_VCPU },
  58         { "msa_fpe",      VCPU_STAT(msa_fpe_exits),      KVM_STAT_VCPU },
  59         { "fpe",          VCPU_STAT(fpe_exits),          KVM_STAT_VCPU },
  60         { "msa_disabled", VCPU_STAT(msa_disabled_exits), KVM_STAT_VCPU },
  61         { "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU },
  62 #ifdef CONFIG_KVM_MIPS_VZ
  63         { "vz_gpsi",      VCPU_STAT(vz_gpsi_exits),      KVM_STAT_VCPU },
  64         { "vz_gsfc",      VCPU_STAT(vz_gsfc_exits),      KVM_STAT_VCPU },
  65         { "vz_hc",        VCPU_STAT(vz_hc_exits),        KVM_STAT_VCPU },
  66         { "vz_grr",       VCPU_STAT(vz_grr_exits),       KVM_STAT_VCPU },
  67         { "vz_gva",       VCPU_STAT(vz_gva_exits),       KVM_STAT_VCPU },
  68         { "vz_ghfc",      VCPU_STAT(vz_ghfc_exits),      KVM_STAT_VCPU },
  69         { "vz_gpa",       VCPU_STAT(vz_gpa_exits),       KVM_STAT_VCPU },
  70         { "vz_resvd",     VCPU_STAT(vz_resvd_exits),     KVM_STAT_VCPU },
  71 #endif
  72         { "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU },
  73         { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), KVM_STAT_VCPU },
  74         { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid), KVM_STAT_VCPU },
  75         { "halt_wakeup",  VCPU_STAT(halt_wakeup),        KVM_STAT_VCPU },
  76         {NULL}
  77 };
  78
  79 bool kvm_trace_guest_mode_change;
  80
  81 int kvm_guest_mode_change_trace_reg(void)
  82 {
  83         kvm_trace_guest_mode_change = 1;
  84         return 0;
  85 }
  86
  87 void kvm_guest_mode_change_trace_unreg(void)
  88 {
  89         kvm_trace_guest_mode_change = 0;
  90 }
  91
  92 /*
  93  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
  94  * Config7, so we are "runnable" if interrupts are pending
  95  */
  96 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
  97 {
  98         return !!(vcpu->arch.pending_exceptions);
  99 }
 100
 101 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
 102 {
 103         return false;
 104 }
 105
 106 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
 107 {
 108         return 1;
 109 }
 110
 111 int kvm_arch_hardware_enable(void)
 112 {
 113         return kvm_mips_callbacks->hardware_enable();
 114 }
 115
 116 void kvm_arch_hardware_disable(void)
 117 {
 118         kvm_mips_callbacks->hardware_disable();
 119 }
 120
 121 int kvm_arch_hardware_setup(void)
 122 {
 123         return 0;
 124 }
 125
 126 void kvm_arch_check_processor_compat(void *rtn)
 127 {
 128         *(int *)rtn = 0;
 129 }
 130
 131 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 132 {
 133         switch (type) {
 134 #ifdef CONFIG_KVM_MIPS_VZ
 135         case KVM_VM_MIPS_VZ:
 136 #else
 137         case KVM_VM_MIPS_TE:
 138 #endif
 139                 break;
 140         default:
 141                 /* Unsupported KVM type */
 142                 return -EINVAL;
 143         };
 144
 145         /* Allocate page table to map GPA -> RPA */
 146         kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
 147         if (!kvm->arch.gpa_mm.pgd)
 148                 return -ENOMEM;
 149
 150         return 0;
 151 }
 152
 153 bool kvm_arch_has_vcpu_debugfs(void)
 154 {
 155         return false;
 156 }
 157
 158 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
 159 {
 160         return 0;
 161 }
 162
 163 void kvm_mips_free_vcpus(struct kvm *kvm)
 164 {
 165         unsigned int i;
 166         struct kvm_vcpu *vcpu;
 167
 168         kvm_for_each_vcpu(i, vcpu, kvm) {
 169                 kvm_arch_vcpu_free(vcpu);
 170         }
 171
 172         mutex_lock(&kvm->lock);
 173
 174         for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
 175                 kvm->vcpus[i] = NULL;
 176
 177         atomic_set(&kvm->online_vcpus, 0);
 178
 179         mutex_unlock(&kvm->lock);
 180 }
 181
 182 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
 183 {
 184         /* It should always be safe to remove after flushing the whole range */
 185         WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
 186         pgd_free(NULL, kvm->arch.gpa_mm.pgd);
 187 }
 188
 189 void kvm_arch_destroy_vm(struct kvm *kvm)
 190 {
 191         kvm_mips_free_vcpus(kvm);
 192         kvm_mips_free_gpa_pt(kvm);
 193 }
 194
 195 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
 196                         unsigned long arg)
 197 {
 198         return -ENOIOCTLCMD;
 199 }
 200
 201 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
 202                             unsigned long npages)
 203 {
 204         return 0;
 205 }
 206
 207 void kvm_arch_flush_shadow_all(struct kvm *kvm)
 208 {
 209         /* Flush whole GPA */
 210         kvm_mips_flush_gpa_pt(kvm, 0, ~0);
 211
 212         /* Let implementation do the rest */
 213         kvm_mips_callbacks->flush_shadow_all(kvm);
 214 }
 215
 216 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
 217                                    struct kvm_memory_slot *slot)
 218 {
 219         /*
 220          * The slot has been made invalid (ready for moving or deletion), so we
 221          * need to ensure that it can no longer be accessed by any guest VCPUs.
 222          */
 223
 224         spin_lock(&kvm->mmu_lock);
 225         /* Flush slot from GPA */
 226         kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
 227                               slot->base_gfn + slot->npages - 1);
 228         /* Let implementation do the rest */
 229         kvm_mips_callbacks->flush_shadow_memslot(kvm, slot);
 230         spin_unlock(&kvm->mmu_lock);
 231 }
 232
 233 int kvm_arch_prepare_memory_region(struct kvm *kvm,
 234                                    struct kvm_memory_slot *memslot,
 235                                    const struct kvm_userspace_memory_region *mem,
 236                                    enum kvm_mr_change change)
 237 {
 238         return 0;
 239 }
 240
 241 void kvm_arch_commit_memory_region(struct kvm *kvm,
 242                                    const struct kvm_userspace_memory_region *mem,
 243                                    const struct kvm_memory_slot *old,
 244                                    const struct kvm_memory_slot *new,
 245                                    enum kvm_mr_change change)
 246 {
 247         int needs_flush;
 248
 249         kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
 250                   __func__, kvm, mem->slot, mem->guest_phys_addr,
 251                   mem->memory_size, mem->userspace_addr);
 252
 253         /*
 254          * If dirty page logging is enabled, write protect all pages in the slot
 255          * ready for dirty logging.
 256          *
 257          * There is no need to do this in any of the following cases:
 258          * CREATE:      No dirty mappings will already exist.
 259          * MOVE/DELETE: The old mappings will already have been cleaned up by
 260          *              kvm_arch_flush_shadow_memslot()
 261          */
 262         if (change == KVM_MR_FLAGS_ONLY &&
 263             (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
 264              new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
 265                 spin_lock(&kvm->mmu_lock);
 266                 /* Write protect GPA page table entries */
 267                 needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
 268                                         new->base_gfn + new->npages - 1);
 269                 /* Let implementation do the rest */
 270                 if (needs_flush)
 271                         kvm_mips_callbacks->flush_shadow_memslot(kvm, new);
 272                 spin_unlock(&kvm->mmu_lock);
 273         }
 274 }
 275
 276 static inline void dump_handler(const char *symbol, void *start, void *end)
 277 {
 278         u32 *p;
 279
 280         pr_debug("LEAF(%s)\n", symbol);
 281
 282         pr_debug("\t.set push\n");
 283         pr_debug("\t.set noreorder\n");
 284
 285         for (p = start; p < (u32 *)end; ++p)
 286                 pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
 287
 288         pr_debug("\t.set\tpop\n");
 289
 290         pr_debug("\tEND(%s)\n", symbol);
 291 }
 292
 293 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 294 {
 295         int err, size;
 296         void *gebase, *p, *handler, *refill_start, *refill_end;
 297         int i;
 298
 299         struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
 300
 301         if (!vcpu) {
 302                 err = -ENOMEM;
 303                 goto out;
 304         }
 305
 306         err = kvm_vcpu_init(vcpu, kvm, id);
 307
 308         if (err)
 309                 goto out_free_cpu;
 310
 311         kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
 312
 313         /*
 314          * Allocate space for host mode exception handlers that handle
 315          * guest mode exits
 316          */
 317         if (cpu_has_veic || cpu_has_vint)
 318                 size = 0x200 + VECTORSPACING * 64;
 319         else
 320                 size = 0x4000;
 321
 322         gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
 323
 324         if (!gebase) {
 325                 err = -ENOMEM;
 326                 goto out_uninit_cpu;
 327         }
 328         kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
 329                   ALIGN(size, PAGE_SIZE), gebase);
 330
 331         /*
 332          * Check new ebase actually fits in CP0_EBase. The lack of a write gate
 333          * limits us to the low 512MB of physical address space. If the memory
 334          * we allocate is out of range, just give up now.
 335          */
 336         if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
 337                 kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
 338                         gebase);
 339                 err = -ENOMEM;
 340                 goto out_free_gebase;
 341         }
 342
 343         /* Save new ebase */
 344         vcpu->arch.guest_ebase = gebase;
 345
 346         /* Build guest exception vectors dynamically in unmapped memory */
 347         handler = gebase + 0x2000;
 348
 349         /* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
 350         refill_start = gebase;
 351         if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
 352                 refill_start += 0x080;
 353         refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
 354
 355         /* General Exception Entry point */
 356         kvm_mips_build_exception(gebase + 0x180, handler);
 357
 358         /* For vectored interrupts poke the exception code @ all offsets 0-7 */
 359         for (i = 0; i < 8; i++) {
 360                 kvm_debug("L1 Vectored handler @ %p\n",
 361                           gebase + 0x200 + (i * VECTORSPACING));
 362                 kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
 363                                          handler);
 364         }
 365
 366         /* General exit handler */
 367         p = handler;
 368         p = kvm_mips_build_exit(p);
 369
 370         /* Guest entry routine */
 371         vcpu->arch.vcpu_run = p;
 372         p = kvm_mips_build_vcpu_run(p);
 373
 374         /* Dump the generated code */
 375         pr_debug("#include <asm/asm.h>\n");
 376         pr_debug("#include <asm/regdef.h>\n");
 377         pr_debug("\n");
 378         dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
 379         dump_handler("kvm_tlb_refill", refill_start, refill_end);
 380         dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
 381         dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
 382
 383         /* Invalidate the icache for these ranges */
 384         flush_icache_range((unsigned long)gebase,
 385                            (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
 386
 387         /*
 388          * Allocate comm page for guest kernel, a TLB will be reserved for
 389          * mapping GVA @ 0xFFFF8000 to this page
 390          */
 391         vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
 392
 393         if (!vcpu->arch.kseg0_commpage) {
 394                 err = -ENOMEM;
 395                 goto out_free_gebase;
 396         }
 397
 398         kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
 399         kvm_mips_commpage_init(vcpu);
 400
 401         /* Init */
 402         vcpu->arch.last_sched_cpu = -1;
 403         vcpu->arch.last_exec_cpu = -1;
 404
 405         return vcpu;
 406
 407 out_free_gebase:
 408         kfree(gebase);
 409
 410 out_uninit_cpu:
 411         kvm_vcpu_uninit(vcpu);
 412
 413 out_free_cpu:
 414         kfree(vcpu);
 415
 416 out:
 417         return ERR_PTR(err);
 418 }
 419
 420 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 421 {
 422         hrtimer_cancel(&vcpu->arch.comparecount_timer);
 423
 424         kvm_vcpu_uninit(vcpu);
 425
 426         kvm_mips_dump_stats(vcpu);
 427
 428         kvm_mmu_free_memory_caches(vcpu);
 429         kfree(vcpu->arch.guest_ebase);
 430         kfree(vcpu->arch.kseg0_commpage);
 431         kfree(vcpu);
 432 }
 433
 434 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 435 {
 436         kvm_arch_vcpu_free(vcpu);
 437 }
 438
 439 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 440                                         struct kvm_guest_debug *dbg)
 441 {
 442         return -ENOIOCTLCMD;
 443 }
 444
 445 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 446 {
 447         int r = -EINTR;
 448
 449         vcpu_load(vcpu);
 450
 451         kvm_sigset_activate(vcpu);
 452
 453         if (vcpu->mmio_needed) {
 454                 if (!vcpu->mmio_is_write)
 455                         kvm_mips_complete_mmio_load(vcpu, run);
 456                 vcpu->mmio_needed = 0;
 457         }
 458
 459         if (run->immediate_exit)
 460                 goto out;
 461
 462         lose_fpu(1);
 463
 464         local_irq_disable();
 465         guest_enter_irqoff();
 466         trace_kvm_enter(vcpu);
 467
 468         /*
 469          * Make sure the read of VCPU requests in vcpu_run() callback is not
 470          * reordered ahead of the write to vcpu->mode, or we could miss a TLB
 471          * flush request while the requester sees the VCPU as outside of guest
 472          * mode and not needing an IPI.
 473          */
 474         smp_store_mb(vcpu->mode, IN_GUEST_MODE);
 475
 476         r = kvm_mips_callbacks->vcpu_run(run, vcpu);
 477
 478         trace_kvm_out(vcpu);
 479         guest_exit_irqoff();
 480         local_irq_enable();
 481
 482 out:
 483         kvm_sigset_deactivate(vcpu);
 484
 485         vcpu_put(vcpu);
 486         return r;
 487 }
 488
 489 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
 490                              struct kvm_mips_interrupt *irq)
 491 {
 492         int intr = (int)irq->irq;
 493         struct kvm_vcpu *dvcpu = NULL;
 494
 495         if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
 496                 kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
 497                           (int)intr);
 498
 499         if (irq->cpu == -1)
 500                 dvcpu = vcpu;
 501         else
 502                 dvcpu = vcpu->kvm->vcpus[irq->cpu];
 503
 504         if (intr == 2 || intr == 3 || intr == 4) {
 505                 kvm_mips_callbacks->queue_io_int(dvcpu, irq);
 506
 507         } else if (intr == -2 || intr == -3 || intr == -4) {
 508                 kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
 509         } else {
 510                 kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
 511                         irq->cpu, irq->irq);
 512                 return -EINVAL;
 513         }
 514
 515         dvcpu->arch.wait = 0;
 516
 517         if (swq_has_sleeper(&dvcpu->wq))
 518                 swake_up_one(&dvcpu->wq);
 519
 520         return 0;
 521 }
 522
 523 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 524                                     struct kvm_mp_state *mp_state)
 525 {
 526         return -ENOIOCTLCMD;
 527 }
 528
 529 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 530                                     struct kvm_mp_state *mp_state)
 531 {
 532         return -ENOIOCTLCMD;
 533 }
 534
 535 static u64 kvm_mips_get_one_regs[] = {
 536         KVM_REG_MIPS_R0,
 537         KVM_REG_MIPS_R1,
 538         KVM_REG_MIPS_R2,
 539         KVM_REG_MIPS_R3,
 540         KVM_REG_MIPS_R4,
 541         KVM_REG_MIPS_R5,
 542         KVM_REG_MIPS_R6,
 543         KVM_REG_MIPS_R7,
 544         KVM_REG_MIPS_R8,
 545         KVM_REG_MIPS_R9,
 546         KVM_REG_MIPS_R10,
 547         KVM_REG_MIPS_R11,
 548         KVM_REG_MIPS_R12,
 549         KVM_REG_MIPS_R13,
 550         KVM_REG_MIPS_R14,
 551         KVM_REG_MIPS_R15,
 552         KVM_REG_MIPS_R16,
 553         KVM_REG_MIPS_R17,
 554         KVM_REG_MIPS_R18,
 555         KVM_REG_MIPS_R19,
 556         KVM_REG_MIPS_R20,
 557         KVM_REG_MIPS_R21,
 558         KVM_REG_MIPS_R22,
 559         KVM_REG_MIPS_R23,
 560         KVM_REG_MIPS_R24,
 561         KVM_REG_MIPS_R25,
 562         KVM_REG_MIPS_R26,
 563         KVM_REG_MIPS_R27,
 564         KVM_REG_MIPS_R28,
 565         KVM_REG_MIPS_R29,
 566         KVM_REG_MIPS_R30,
 567         KVM_REG_MIPS_R31,
 568
 569 #ifndef CONFIG_CPU_MIPSR6
 570         KVM_REG_MIPS_HI,
 571         KVM_REG_MIPS_LO,
 572 #endif
 573         KVM_REG_MIPS_PC,
 574 };
 575
 576 static u64 kvm_mips_get_one_regs_fpu[] = {
 577         KVM_REG_MIPS_FCR_IR,
 578         KVM_REG_MIPS_FCR_CSR,
 579 };
 580
 581 static u64 kvm_mips_get_one_regs_msa[] = {
 582         KVM_REG_MIPS_MSA_IR,
 583         KVM_REG_MIPS_MSA_CSR,
 584 };
 585
 586 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
 587 {
 588         unsigned long ret;
 589
 590         ret = ARRAY_SIZE(kvm_mips_get_one_regs);
 591         if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
 592                 ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
 593                 /* odd doubles */
 594                 if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
 595                         ret += 16;
 596         }
 597         if (kvm_mips_guest_can_have_msa(&vcpu->arch))
 598                 ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
 599         ret += kvm_mips_callbacks->num_regs(vcpu);
 600
 601         return ret;
 602 }
 603
 604 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
 605 {
 606         u64 index;
 607         unsigned int i;
 608
 609         if (copy_to_user(indices, kvm_mips_get_one_regs,
 610                          sizeof(kvm_mips_get_one_regs)))
 611                 return -EFAULT;
 612         indices += ARRAY_SIZE(kvm_mips_get_one_regs);
 613
 614         if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
 615                 if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
 616                                  sizeof(kvm_mips_get_one_regs_fpu)))
 617                         return -EFAULT;
 618                 indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
 619
 620                 for (i = 0; i < 32; ++i) {
 621                         index = KVM_REG_MIPS_FPR_32(i);
 622                         if (copy_to_user(indices, &index, sizeof(index)))
 623                                 return -EFAULT;
 624                         ++indices;
 625
 626                         /* skip odd doubles if no F64 */
 627                         if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
 628                                 continue;
 629
 630                         index = KVM_REG_MIPS_FPR_64(i);
 631                         if (copy_to_user(indices, &index, sizeof(index)))
 632                                 return -EFAULT;
 633                         ++indices;
 634                 }
 635         }
 636
 637         if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
 638                 if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
 639                                  sizeof(kvm_mips_get_one_regs_msa)))
 640                         return -EFAULT;
 641                 indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
 642
 643                 for (i = 0; i < 32; ++i) {
 644                         index = KVM_REG_MIPS_VEC_128(i);
 645                         if (copy_to_user(indices, &index, sizeof(index)))
 646                                 return -EFAULT;
 647                         ++indices;
 648                 }
 649         }
 650
 651         return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
 652 }
 653
 654 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
 655                             const struct kvm_one_reg *reg)
 656 {
 657         struct mips_coproc *cop0 = vcpu->arch.cop0;
 658         struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
 659         int ret;
 660         s64 v;
 661         s64 vs[2];
 662         unsigned int idx;
 663
 664         switch (reg->id) {
 665         /* General purpose registers */
 666         case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
 667                 v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
 668                 break;
 669 #ifndef CONFIG_CPU_MIPSR6
 670         case KVM_REG_MIPS_HI:
 671                 v = (long)vcpu->arch.hi;
 672                 break;
 673         case KVM_REG_MIPS_LO:
 674                 v = (long)vcpu->arch.lo;
 675                 break;
 676 #endif
 677         case KVM_REG_MIPS_PC:
 678                 v = (long)vcpu->arch.pc;
 679                 break;
 680
 681         /* Floating point registers */
 682         case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
 683                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 684                         return -EINVAL;
 685                 idx = reg->id - KVM_REG_MIPS_FPR_32(0);
 686                 /* Odd singles in top of even double when FR=0 */
 687                 if (kvm_read_c0_guest_status(cop0) & ST0_FR)
 688                         v = get_fpr32(&fpu->fpr[idx], 0);
 689                 else
 690                         v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
 691                 break;
 692         case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
 693                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 694                         return -EINVAL;
 695                 idx = reg->id - KVM_REG_MIPS_FPR_64(0);
 696                 /* Can't access odd doubles in FR=0 mode */
 697                 if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
 698                         return -EINVAL;
 699                 v = get_fpr64(&fpu->fpr[idx], 0);
 700                 break;
 701         case KVM_REG_MIPS_FCR_IR:
 702                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 703                         return -EINVAL;
 704                 v = boot_cpu_data.fpu_id;
 705                 break;
 706         case KVM_REG_MIPS_FCR_CSR:
 707                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 708                         return -EINVAL;
 709                 v = fpu->fcr31;
 710                 break;
 711
 712         /* MIPS SIMD Architecture (MSA) registers */
 713         case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
 714                 if (!kvm_mips_guest_has_msa(&vcpu->arch))
 715                         return -EINVAL;
 716                 /* Can't access MSA registers in FR=0 mode */
 717                 if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
 718                         return -EINVAL;
 719                 idx = reg->id - KVM_REG_MIPS_VEC_128(0);
 720 #ifdef CONFIG_CPU_LITTLE_ENDIAN
 721                 /* least significant byte first */
 722                 vs[0] = get_fpr64(&fpu->fpr[idx], 0);
 723                 vs[1] = get_fpr64(&fpu->fpr[idx], 1);
 724 #else
 725                 /* most significant byte first */
 726                 vs[0] = get_fpr64(&fpu->fpr[idx], 1);
 727                 vs[1] = get_fpr64(&fpu->fpr[idx], 0);
 728 #endif
 729                 break;
 730         case KVM_REG_MIPS_MSA_IR:
 731                 if (!kvm_mips_guest_has_msa(&vcpu->arch))
 732                         return -EINVAL;
 733                 v = boot_cpu_data.msa_id;
 734                 break;
 735         case KVM_REG_MIPS_MSA_CSR:
 736                 if (!kvm_mips_guest_has_msa(&vcpu->arch))
 737                         return -EINVAL;
 738                 v = fpu->msacsr;
 739                 break;
 740
 741         /* registers to be handled specially */
 742         default:
 743                 ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
 744                 if (ret)
 745                         return ret;
 746                 break;
 747         }
 748         if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
 749                 u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
 750
 751                 return put_user(v, uaddr64);
 752         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
 753                 u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
 754                 u32 v32 = (u32)v;
 755
 756                 return put_user(v32, uaddr32);
 757         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
 758                 void __user *uaddr = (void __user *)(long)reg->addr;
 759
 760                 return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
 761         } else {
 762                 return -EINVAL;
 763         }
 764 }
 765
 766 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
 767                             const struct kvm_one_reg *reg)
 768 {
 769         struct mips_coproc *cop0 = vcpu->arch.cop0;
 770         struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
 771         s64 v;
 772         s64 vs[2];
 773         unsigned int idx;
 774
 775         if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
 776                 u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
 777
 778                 if (get_user(v, uaddr64) != 0)
 779                         return -EFAULT;
 780         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
 781                 u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
 782                 s32 v32;
 783
 784                 if (get_user(v32, uaddr32) != 0)
 785                         return -EFAULT;
 786                 v = (s64)v32;
 787         } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
 788                 void __user *uaddr = (void __user *)(long)reg->addr;
 789
 790                 return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
 791         } else {
 792                 return -EINVAL;
 793         }
 794
 795         switch (reg->id) {
 796         /* General purpose registers */
 797         case KVM_REG_MIPS_R0:
 798                 /* Silently ignore requests to set $0 */
 799                 break;
 800         case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
 801                 vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
 802                 break;
 803 #ifndef CONFIG_CPU_MIPSR6
 804         case KVM_REG_MIPS_HI:
 805                 vcpu->arch.hi = v;
 806                 break;
 807         case KVM_REG_MIPS_LO:
 808                 vcpu->arch.lo = v;
 809                 break;
 810 #endif
 811         case KVM_REG_MIPS_PC:
 812                 vcpu->arch.pc = v;
 813                 break;
 814
 815         /* Floating point registers */
 816         case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
 817                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 818                         return -EINVAL;
 819                 idx = reg->id - KVM_REG_MIPS_FPR_32(0);
 820                 /* Odd singles in top of even double when FR=0 */
 821                 if (kvm_read_c0_guest_status(cop0) & ST0_FR)
 822                         set_fpr32(&fpu->fpr[idx], 0, v);
 823                 else
 824                         set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
 825                 break;
 826         case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
 827                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 828                         return -EINVAL;
 829                 idx = reg->id - KVM_REG_MIPS_FPR_64(0);
 830                 /* Can't access odd doubles in FR=0 mode */
 831                 if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
 832                         return -EINVAL;
 833                 set_fpr64(&fpu->fpr[idx], 0, v);
 834                 break;
 835         case KVM_REG_MIPS_FCR_IR:
 836                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 837                         return -EINVAL;
 838                 /* Read-only */
 839                 break;
 840         case KVM_REG_MIPS_FCR_CSR:
 841                 if (!kvm_mips_guest_has_fpu(&vcpu->arch))
 842                         return -EINVAL;
 843                 fpu->fcr31 = v;
 844                 break;
 845
 846         /* MIPS SIMD Architecture (MSA) registers */
 847         case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
 848                 if (!kvm_mips_guest_has_msa(&vcpu->arch))
 849                         return -EINVAL;
 850                 idx = reg->id - KVM_REG_MIPS_VEC_128(0);
 851 #ifdef CONFIG_CPU_LITTLE_ENDIAN
 852                 /* least significant byte first */
 853                 set_fpr64(&fpu->fpr[idx], 0, vs[0]);
 854                 set_fpr64(&fpu->fpr[idx], 1, vs[1]);
 855 #else
 856                 /* most significant byte first */
 857                 set_fpr64(&fpu->fpr[idx], 1, vs[0]);
 858                 set_fpr64(&fpu->fpr[idx], 0, vs[1]);
 859 #endif
 860                 break;
 861         case KVM_REG_MIPS_MSA_IR:
 862                 if (!kvm_mips_guest_has_msa(&vcpu->arch))
 863                         return -EINVAL;
 864                 /* Read-only */
 865                 break;
 866         case KVM_REG_MIPS_MSA_CSR:
 867                 if (!kvm_mips_guest_has_msa(&vcpu->arch))
 868                         return -EINVAL;
 869                 fpu->msacsr = v;
 870                 break;
 871
 872         /* registers to be handled specially */
 873         default:
 874                 return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
 875         }
 876         return 0;
 877 }
 878
 879 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
 880                                      struct kvm_enable_cap *cap)
 881 {
 882         int r = 0;
 883
 884         if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
 885                 return -EINVAL;
 886         if (cap->flags)
 887                 return -EINVAL;
 888         if (cap->args[0])
 889                 return -EINVAL;
 890
 891         switch (cap->cap) {
 892         case KVM_CAP_MIPS_FPU:
 893                 vcpu->arch.fpu_enabled = true;
 894                 break;
 895         case KVM_CAP_MIPS_MSA:
 896                 vcpu->arch.msa_enabled = true;
 897                 break;
 898         default:
 899                 r = -EINVAL;
 900                 break;
 901         }
 902
 903         return r;
 904 }
 905
 906 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
 907                                unsigned long arg)
 908 {
 909         struct kvm_vcpu *vcpu = filp->private_data;
 910         void __user *argp = (void __user *)arg;
 911
 912         if (ioctl == KVM_INTERRUPT) {
 913                 struct kvm_mips_interrupt irq;
 914
 915                 if (copy_from_user(&irq, argp, sizeof(irq)))
 916                         return -EFAULT;
 917                 kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
 918                           irq.irq);
 919
 920                 return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
 921         }
 922
 923         return -ENOIOCTLCMD;
 924 }
 925
 926 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
 927                          unsigned long arg)
 928 {
 929         struct kvm_vcpu *vcpu = filp->private_data;
 930         void __user *argp = (void __user *)arg;
 931         long r;
 932
 933         vcpu_load(vcpu);
 934
 935         switch (ioctl) {
 936         case KVM_SET_ONE_REG:
 937         case KVM_GET_ONE_REG: {
 938                 struct kvm_one_reg reg;
 939
 940                 r = -EFAULT;
 941                 if (copy_from_user(&reg, argp, sizeof(reg)))
 942                         break;
 943                 if (ioctl == KVM_SET_ONE_REG)
 944                         r = kvm_mips_set_reg(vcpu, &reg);
 945                 else
 946                         r = kvm_mips_get_reg(vcpu, &reg);
 947                 break;
 948         }
 949         case KVM_GET_REG_LIST: {
 950                 struct kvm_reg_list __user *user_list = argp;
 951                 struct kvm_reg_list reg_list;
 952                 unsigned n;
 953
 954                 r = -EFAULT;
 955                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
 956                         break;
 957                 n = reg_list.n;
 958                 reg_list.n = kvm_mips_num_regs(vcpu);
 959                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
 960                         break;
 961                 r = -E2BIG;
 962                 if (n < reg_list.n)
 963                         break;
 964                 r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
 965                 break;
 966         }
 967         case KVM_ENABLE_CAP: {
 968                 struct kvm_enable_cap cap;
 969
 970                 r = -EFAULT;
 971                 if (copy_from_user(&cap, argp, sizeof(cap)))
 972                         break;
 973                 r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
 974                 break;
 975         }
 976         default:
 977                 r = -ENOIOCTLCMD;
 978         }
 979
 980         vcpu_put(vcpu);
 981         return r;
 982 }
 983
 984 /**
 985  * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
 986  * @kvm: kvm instance
 987  * @log: slot id and address to which we copy the log
 988  *
 989  * Steps 1-4 below provide general overview of dirty page logging. See
 990  * kvm_get_dirty_log_protect() function description for additional details.
 991  *
 992  * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
 993  * always flush the TLB (step 4) even if previous step failed  and the dirty
 994  * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
 995  * does not preclude user space subsequent dirty log read. Flushing TLB ensures
 996  * writes will be marked dirty for next log read.
 997  *
 998  *   1. Take a snapshot of the bit and clear it if needed.
 999  *   2. Write protect the corresponding page.
1000  *   3. Copy the snapshot to the userspace.
1001  *   4. Flush TLB's if needed.
1002  */
1003 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
1004 {
1005         struct kvm_memslots *slots;
1006         struct kvm_memory_slot *memslot;
1007         bool flush = false;
1008         int r;
1009
1010         mutex_lock(&kvm->slots_lock);
1011
1012         r = kvm_get_dirty_log_protect(kvm, log, &flush);
1013
1014         if (flush) {
1015                 slots = kvm_memslots(kvm);
1016                 memslot = id_to_memslot(slots, log->slot);
1017
1018                 /* Let implementation handle TLB/GVA invalidation */
1019                 kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1020         }
1021
1022         mutex_unlock(&kvm->slots_lock);
1023         return r;
1024 }
1025
1026 int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, struct kvm_clear_dirty_log *log)
1027 {
1028         struct kvm_memslots *slots;
1029         struct kvm_memory_slot *memslot;
1030         bool flush = false;
1031         int r;
1032
1033         mutex_lock(&kvm->slots_lock);
1034
1035         r = kvm_clear_dirty_log_protect(kvm, log, &flush);
1036
1037         if (flush) {
1038                 slots = kvm_memslots(kvm);
1039                 memslot = id_to_memslot(slots, log->slot);
1040
1041                 /* Let implementation handle TLB/GVA invalidation */
1042                 kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1043         }
1044
1045         mutex_unlock(&kvm->slots_lock);
1046         return r;
1047 }
1048
1049 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1050 {
1051         long r;
1052
1053         switch (ioctl) {
1054         default:
1055                 r = -ENOIOCTLCMD;
1056         }
1057
1058         return r;
1059 }
1060
1061 int kvm_arch_init(void *opaque)
1062 {
1063         if (kvm_mips_callbacks) {
1064                 kvm_err("kvm: module already exists\n");
1065                 return -EEXIST;
1066         }
1067
1068         return kvm_mips_emulation_init(&kvm_mips_callbacks);
1069 }
1070
1071 void kvm_arch_exit(void)
1072 {
1073         kvm_mips_callbacks = NULL;
1074 }
1075
1076 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1077                                   struct kvm_sregs *sregs)
1078 {
1079         return -ENOIOCTLCMD;
1080 }
1081
1082 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1083                                   struct kvm_sregs *sregs)
1084 {
1085         return -ENOIOCTLCMD;
1086 }
1087
1088 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1089 {
1090 }
1091
1092 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1093 {
1094         return -ENOIOCTLCMD;
1095 }
1096
1097 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1098 {
1099         return -ENOIOCTLCMD;
1100 }
1101
1102 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1103 {
1104         return VM_FAULT_SIGBUS;
1105 }
1106
1107 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1108 {
1109         int r;
1110
1111         switch (ext) {
1112         case KVM_CAP_ONE_REG:
1113         case KVM_CAP_ENABLE_CAP:
1114         case KVM_CAP_READONLY_MEM:
1115         case KVM_CAP_SYNC_MMU:
1116         case KVM_CAP_IMMEDIATE_EXIT:
1117                 r = 1;
1118                 break;
1119         case KVM_CAP_NR_VCPUS:
1120                 r = num_online_cpus();
1121                 break;
1122         case KVM_CAP_MAX_VCPUS:
1123                 r = KVM_MAX_VCPUS;
1124                 break;
1125         case KVM_CAP_MAX_VCPU_ID:
1126                 r = KVM_MAX_VCPU_ID;
1127                 break;
1128         case KVM_CAP_MIPS_FPU:
1129                 /* We don't handle systems with inconsistent cpu_has_fpu */
1130                 r = !!raw_cpu_has_fpu;
1131                 break;
1132         case KVM_CAP_MIPS_MSA:
1133                 /*
1134                  * We don't support MSA vector partitioning yet:
1135                  * 1) It would require explicit support which can't be tested
1136                  *    yet due to lack of support in current hardware.
1137                  * 2) It extends the state that would need to be saved/restored
1138                  *    by e.g. QEMU for migration.
1139                  *
1140                  * When vector partitioning hardware becomes available, support
1141                  * could be added by requiring a flag when enabling
1142                  * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1143                  * to save/restore the appropriate extra state.
1144                  */
1145                 r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1146                 break;
1147         default:
1148                 r = kvm_mips_callbacks->check_extension(kvm, ext);
1149                 break;
1150         }
1151         return r;
1152 }
1153
1154 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1155 {
1156         return kvm_mips_pending_timer(vcpu) ||
1157                 kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1158 }
1159
1160 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1161 {
1162         int i;
1163         struct mips_coproc *cop0;
1164
1165         if (!vcpu)
1166                 return -1;
1167
1168         kvm_debug("VCPU Register Dump:\n");
1169         kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1170         kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1171
1172         for (i = 0; i < 32; i += 4) {
1173                 kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1174                        vcpu->arch.gprs[i],
1175                        vcpu->arch.gprs[i + 1],
1176                        vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1177         }
1178         kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1179         kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1180
1181         cop0 = vcpu->arch.cop0;
1182         kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1183                   kvm_read_c0_guest_status(cop0),
1184                   kvm_read_c0_guest_cause(cop0));
1185
1186         kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1187
1188         return 0;
1189 }
1190
1191 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1192 {
1193         int i;
1194
1195         vcpu_load(vcpu);
1196
1197         for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1198                 vcpu->arch.gprs[i] = regs->gpr[i];
1199         vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1200         vcpu->arch.hi = regs->hi;
1201         vcpu->arch.lo = regs->lo;
1202         vcpu->arch.pc = regs->pc;
1203
1204         vcpu_put(vcpu);
1205         return 0;
1206 }
1207
1208 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1209 {
1210         int i;
1211
1212         vcpu_load(vcpu);
1213
1214         for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1215                 regs->gpr[i] = vcpu->arch.gprs[i];
1216
1217         regs->hi = vcpu->arch.hi;
1218         regs->lo = vcpu->arch.lo;
1219         regs->pc = vcpu->arch.pc;
1220
1221         vcpu_put(vcpu);
1222         return 0;
1223 }
1224
1225 static void kvm_mips_comparecount_func(unsigned long data)
1226 {
1227         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
1228
1229         kvm_mips_callbacks->queue_timer_int(vcpu);
1230
1231         vcpu->arch.wait = 0;
1232         if (swq_has_sleeper(&vcpu->wq))
1233                 swake_up_one(&vcpu->wq);
1234 }
1235
1236 /* low level hrtimer wake routine */
1237 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
1238 {
1239         struct kvm_vcpu *vcpu;
1240
1241         vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
1242         kvm_mips_comparecount_func((unsigned long) vcpu);
1243         return kvm_mips_count_timeout(vcpu);
1244 }
1245
1246 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
1247 {
1248         int err;
1249
1250         err = kvm_mips_callbacks->vcpu_init(vcpu);
1251         if (err)
1252                 return err;
1253
1254         hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
1255                      HRTIMER_MODE_REL);
1256         vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
1257         return 0;
1258 }
1259
1260 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
1261 {
1262         kvm_mips_callbacks->vcpu_uninit(vcpu);
1263 }
1264
1265 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1266                                   struct kvm_translation *tr)
1267 {
1268         return 0;
1269 }
1270
1271 /* Initial guest state */
1272 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
1273 {
1274         return kvm_mips_callbacks->vcpu_setup(vcpu);
1275 }
1276
1277 static void kvm_mips_set_c0_status(void)
1278 {
1279         u32 status = read_c0_status();
1280
1281         if (cpu_has_dsp)
1282                 status |= (ST0_MX);
1283
1284         write_c0_status(status);
1285         ehb();
1286 }
1287
1288 /*
1289  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1290  */
1291 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1292 {
1293         u32 cause = vcpu->arch.host_cp0_cause;
1294         u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1295         u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1296         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1297         enum emulation_result er = EMULATE_DONE;
1298         u32 inst;
1299         int ret = RESUME_GUEST;
1300
1301         vcpu->mode = OUTSIDE_GUEST_MODE;
1302
1303         /* re-enable HTW before enabling interrupts */
1304         if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1305                 htw_start();
1306
1307         /* Set a default exit reason */
1308         run->exit_reason = KVM_EXIT_UNKNOWN;
1309         run->ready_for_interrupt_injection = 1;
1310
1311         /*
1312          * Set the appropriate status bits based on host CPU features,
1313          * before we hit the scheduler
1314          */
1315         kvm_mips_set_c0_status();
1316
1317         local_irq_enable();
1318
1319         kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1320                         cause, opc, run, vcpu);
1321         trace_kvm_exit(vcpu, exccode);
1322
1323         if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1324                 /*
1325                  * Do a privilege check, if in UM most of these exit conditions
1326                  * end up causing an exception to be delivered to the Guest
1327                  * Kernel
1328                  */
1329                 er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1330                 if (er == EMULATE_PRIV_FAIL) {
1331                         goto skip_emul;
1332                 } else if (er == EMULATE_FAIL) {
1333                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1334                         ret = RESUME_HOST;
1335                         goto skip_emul;
1336                 }
1337         }
1338
1339         switch (exccode) {
1340         case EXCCODE_INT:
1341                 kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1342
1343                 ++vcpu->stat.int_exits;
1344
1345                 if (need_resched())
1346                         cond_resched();
1347
1348                 ret = RESUME_GUEST;
1349                 break;
1350
1351         case EXCCODE_CPU:
1352                 kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1353
1354                 ++vcpu->stat.cop_unusable_exits;
1355                 ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1356                 /* XXXKYMA: Might need to return to user space */
1357                 if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1358                         ret = RESUME_HOST;
1359                 break;
1360
1361         case EXCCODE_MOD:
1362                 ++vcpu->stat.tlbmod_exits;
1363                 ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1364                 break;
1365
1366         case EXCCODE_TLBS:
1367                 kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1368                           cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1369                           badvaddr);
1370
1371                 ++vcpu->stat.tlbmiss_st_exits;
1372                 ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1373                 break;
1374
1375         case EXCCODE_TLBL:
1376                 kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1377                           cause, opc, badvaddr);
1378
1379                 ++vcpu->stat.tlbmiss_ld_exits;
1380                 ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1381                 break;
1382
1383         case EXCCODE_ADES:
1384                 ++vcpu->stat.addrerr_st_exits;
1385                 ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1386                 break;
1387
1388         case EXCCODE_ADEL:
1389                 ++vcpu->stat.addrerr_ld_exits;
1390                 ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1391                 break;
1392
1393         case EXCCODE_SYS:
1394                 ++vcpu->stat.syscall_exits;
1395                 ret = kvm_mips_callbacks->handle_syscall(vcpu);
1396                 break;
1397
1398         case EXCCODE_RI:
1399                 ++vcpu->stat.resvd_inst_exits;
1400                 ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1401                 break;
1402
1403         case EXCCODE_BP:
1404                 ++vcpu->stat.break_inst_exits;
1405                 ret = kvm_mips_callbacks->handle_break(vcpu);
1406                 break;
1407
1408         case EXCCODE_TR:
1409                 ++vcpu->stat.trap_inst_exits;
1410                 ret = kvm_mips_callbacks->handle_trap(vcpu);
1411                 break;
1412
1413         case EXCCODE_MSAFPE:
1414                 ++vcpu->stat.msa_fpe_exits;
1415                 ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1416                 break;
1417
1418         case EXCCODE_FPE:
1419                 ++vcpu->stat.fpe_exits;
1420                 ret = kvm_mips_callbacks->handle_fpe(vcpu);
1421                 break;
1422
1423         case EXCCODE_MSADIS:
1424                 ++vcpu->stat.msa_disabled_exits;
1425                 ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1426                 break;
1427
1428         case EXCCODE_GE:
1429                 /* defer exit accounting to handler */
1430                 ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1431                 break;
1432
1433         default:
1434                 if (cause & CAUSEF_BD)
1435                         opc += 1;
1436                 inst = 0;
1437                 kvm_get_badinstr(opc, vcpu, &inst);
1438                 kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1439                         exccode, opc, inst, badvaddr,
1440                         kvm_read_c0_guest_status(vcpu->arch.cop0));
1441                 kvm_arch_vcpu_dump_regs(vcpu);
1442                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1443                 ret = RESUME_HOST;
1444                 break;
1445
1446         }
1447
1448 skip_emul:
1449         local_irq_disable();
1450
1451         if (ret == RESUME_GUEST)
1452                 kvm_vz_acquire_htimer(vcpu);
1453
1454         if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1455                 kvm_mips_deliver_interrupts(vcpu, cause);
1456
1457         if (!(ret & RESUME_HOST)) {
1458                 /* Only check for signals if not already exiting to userspace */
1459                 if (signal_pending(current)) {
1460                         run->exit_reason = KVM_EXIT_INTR;
1461                         ret = (-EINTR << 2) | RESUME_HOST;
1462                         ++vcpu->stat.signal_exits;
1463                         trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1464                 }
1465         }
1466
1467         if (ret == RESUME_GUEST) {
1468                 trace_kvm_reenter(vcpu);
1469
1470                 /*
1471                  * Make sure the read of VCPU requests in vcpu_reenter()
1472                  * callback is not reordered ahead of the write to vcpu->mode,
1473                  * or we could miss a TLB flush request while the requester sees
1474                  * the VCPU as outside of guest mode and not needing an IPI.
1475                  */
1476                 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1477
1478                 kvm_mips_callbacks->vcpu_reenter(run, vcpu);
1479
1480                 /*
1481                  * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1482                  * is live), restore FCR31 / MSACSR.
1483                  *
1484                  * This should be before returning to the guest exception
1485                  * vector, as it may well cause an [MSA] FP exception if there
1486                  * are pending exception bits unmasked. (see
1487                  * kvm_mips_csr_die_notifier() for how that is handled).
1488                  */
1489                 if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1490                     read_c0_status() & ST0_CU1)
1491                         __kvm_restore_fcsr(&vcpu->arch);
1492
1493                 if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1494                     read_c0_config5() & MIPS_CONF5_MSAEN)
1495                         __kvm_restore_msacsr(&vcpu->arch);
1496         }
1497
1498         /* Disable HTW before returning to guest or host */
1499         if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1500                 htw_stop();
1501
1502         return ret;
1503 }
1504
1505 /* Enable FPU for guest and restore context */
1506 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1507 {
1508         struct mips_coproc *cop0 = vcpu->arch.cop0;
1509         unsigned int sr, cfg5;
1510
1511         preempt_disable();
1512
1513         sr = kvm_read_c0_guest_status(cop0);
1514
1515         /*
1516          * If MSA state is already live, it is undefined how it interacts with
1517          * FR=0 FPU state, and we don't want to hit reserved instruction
1518          * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1519          * play it safe and save it first.
1520          *
1521          * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1522          * get called when guest CU1 is set, however we can't trust the guest
1523          * not to clobber the status register directly via the commpage.
1524          */
1525         if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1526             vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1527                 kvm_lose_fpu(vcpu);
1528
1529         /*
1530          * Enable FPU for guest
1531          * We set FR and FRE according to guest context
1532          */
1533         change_c0_status(ST0_CU1 | ST0_FR, sr);
1534         if (cpu_has_fre) {
1535                 cfg5 = kvm_read_c0_guest_config5(cop0);
1536                 change_c0_config5(MIPS_CONF5_FRE, cfg5);
1537         }
1538         enable_fpu_hazard();
1539
1540         /* If guest FPU state not active, restore it now */
1541         if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1542                 __kvm_restore_fpu(&vcpu->arch);
1543                 vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1544                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1545         } else {
1546                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1547         }
1548
1549         preempt_enable();
1550 }
1551
1552 #ifdef CONFIG_CPU_HAS_MSA
1553 /* Enable MSA for guest and restore context */
1554 void kvm_own_msa(struct kvm_vcpu *vcpu)
1555 {
1556         struct mips_coproc *cop0 = vcpu->arch.cop0;
1557         unsigned int sr, cfg5;
1558
1559         preempt_disable();
1560
1561         /*
1562          * Enable FPU if enabled in guest, since we're restoring FPU context
1563          * anyway. We set FR and FRE according to guest context.
1564          */
1565         if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1566                 sr = kvm_read_c0_guest_status(cop0);
1567
1568                 /*
1569                  * If FR=0 FPU state is already live, it is undefined how it
1570                  * interacts with MSA state, so play it safe and save it first.
1571                  */
1572                 if (!(sr & ST0_FR) &&
1573                     (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1574                                 KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1575                         kvm_lose_fpu(vcpu);
1576
1577                 change_c0_status(ST0_CU1 | ST0_FR, sr);
1578                 if (sr & ST0_CU1 && cpu_has_fre) {
1579                         cfg5 = kvm_read_c0_guest_config5(cop0);
1580                         change_c0_config5(MIPS_CONF5_FRE, cfg5);
1581                 }
1582         }
1583
1584         /* Enable MSA for guest */
1585         set_c0_config5(MIPS_CONF5_MSAEN);
1586         enable_fpu_hazard();
1587
1588         switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1589         case KVM_MIPS_AUX_FPU:
1590                 /*
1591                  * Guest FPU state already loaded, only restore upper MSA state
1592                  */
1593                 __kvm_restore_msa_upper(&vcpu->arch);
1594                 vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1595                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1596                 break;
1597         case 0:
1598                 /* Neither FPU or MSA already active, restore full MSA state */
1599                 __kvm_restore_msa(&vcpu->arch);
1600                 vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1601                 if (kvm_mips_guest_has_fpu(&vcpu->arch))
1602                         vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1603                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1604                               KVM_TRACE_AUX_FPU_MSA);
1605                 break;
1606         default:
1607                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1608                 break;
1609         }
1610
1611         preempt_enable();
1612 }
1613 #endif
1614
1615 /* Drop FPU & MSA without saving it */
1616 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1617 {
1618         preempt_disable();
1619         if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1620                 disable_msa();
1621                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1622                 vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1623         }
1624         if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1625                 clear_c0_status(ST0_CU1 | ST0_FR);
1626                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1627                 vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1628         }
1629         preempt_enable();
1630 }
1631
1632 /* Save and disable FPU & MSA */
1633 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1634 {
1635         /*
1636          * With T&E, FPU & MSA get disabled in root context (hardware) when it
1637          * is disabled in guest context (software), but the register state in
1638          * the hardware may still be in use.
1639          * This is why we explicitly re-enable the hardware before saving.
1640          */
1641
1642         preempt_disable();
1643         if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1644                 if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1645                         set_c0_config5(MIPS_CONF5_MSAEN);
1646                         enable_fpu_hazard();
1647                 }
1648
1649                 __kvm_save_msa(&vcpu->arch);
1650                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1651
1652                 /* Disable MSA & FPU */
1653                 disable_msa();
1654                 if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1655                         clear_c0_status(ST0_CU1 | ST0_FR);
1656                         disable_fpu_hazard();
1657                 }
1658                 vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1659         } else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1660                 if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1661                         set_c0_status(ST0_CU1);
1662                         enable_fpu_hazard();
1663                 }
1664
1665                 __kvm_save_fpu(&vcpu->arch);
1666                 vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1667                 trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1668
1669                 /* Disable FPU */
1670                 clear_c0_status(ST0_CU1 | ST0_FR);
1671                 disable_fpu_hazard();
1672         }
1673         preempt_enable();
1674 }
1675
1676 /*
1677  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1678  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1679  * exception if cause bits are set in the value being written.
1680  */
1681 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1682                                    unsigned long cmd, void *ptr)
1683 {
1684         struct die_args *args = (struct die_args *)ptr;
1685         struct pt_regs *regs = args->regs;
1686         unsigned long pc;
1687
1688         /* Only interested in FPE and MSAFPE */
1689         if (cmd != DIE_FP && cmd != DIE_MSAFP)
1690                 return NOTIFY_DONE;
1691
1692         /* Return immediately if guest context isn't active */
1693         if (!(current->flags & PF_VCPU))
1694                 return NOTIFY_DONE;
1695
1696         /* Should never get here from user mode */
1697         BUG_ON(user_mode(regs));
1698
1699         pc = instruction_pointer(regs);
1700         switch (cmd) {
1701         case DIE_FP:
1702                 /* match 2nd instruction in __kvm_restore_fcsr */
1703                 if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1704                         return NOTIFY_DONE;
1705                 break;
1706         case DIE_MSAFP:
1707                 /* match 2nd/3rd instruction in __kvm_restore_msacsr */
1708                 if (!cpu_has_msa ||
1709                     pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1710                     pc > (unsigned long)&__kvm_restore_msacsr + 8)
1711                         return NOTIFY_DONE;
1712                 break;
1713         }
1714
1715         /* Move PC forward a little and continue executing */
1716         instruction_pointer(regs) += 4;
1717
1718         return NOTIFY_STOP;
1719 }
1720
1721 static struct notifier_block kvm_mips_csr_die_notifier = {
1722         .notifier_call = kvm_mips_csr_die_notify,
1723 };
1724
1725 static int __init kvm_mips_init(void)
1726 {
1727         int ret;
1728
1729         if (cpu_has_mmid) {
1730                 pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1731                 return -EOPNOTSUPP;
1732         }
1733
1734         ret = kvm_mips_entry_setup();
1735         if (ret)
1736                 return ret;
1737
1738         ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1739
1740         if (ret)
1741                 return ret;
1742
1743         register_die_notifier(&kvm_mips_csr_die_notifier);
1744
1745         return 0;
1746 }
1747
1748 static void __exit kvm_mips_exit(void)
1749 {
1750         kvm_exit();
1751
1752         unregister_die_notifier(&kvm_mips_csr_die_notifier);
1753 }
1754
1755 module_init(kvm_mips_init);
1756 module_exit(kvm_mips_exit);
1757
1758 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);