arch/mips/kvm/tlb.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 TLB handling, this file is part of the Linux host kernel so that
   7  * TLB handlers run from KSEG0
   8  *
   9  * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
  10  * Authors: Sanjay Lal <sanjayl@kymasys.com>
  11  */
  12
  13 #include <linux/sched.h>
  14 #include <linux/smp.h>
  15 #include <linux/mm.h>
  16 #include <linux/delay.h>
  17 #include <linux/module.h>
  18 #include <linux/kvm_host.h>
  19 #include <linux/srcu.h>
  20
  21 #include <asm/cpu.h>
  22 #include <asm/bootinfo.h>
  23 #include <asm/mmu_context.h>
  24 #include <asm/pgtable.h>
  25 #include <asm/cacheflush.h>
  26 #include <asm/tlb.h>
  27
  28 #undef CONFIG_MIPS_MT
  29 #include <asm/r4kcache.h>
  30 #define CONFIG_MIPS_MT
  31
  32 #define KVM_GUEST_PC_TLB    0
  33 #define KVM_GUEST_SP_TLB    1
  34
  35 #define PRIx64 "llx"
  36
  37 atomic_t kvm_mips_instance;
  38 EXPORT_SYMBOL(kvm_mips_instance);
  39
  40 /* These function pointers are initialized once the KVM module is loaded */
  41 pfn_t (*kvm_mips_gfn_to_pfn)(struct kvm *kvm, gfn_t gfn);
  42 EXPORT_SYMBOL(kvm_mips_gfn_to_pfn);
  43
  44 void (*kvm_mips_release_pfn_clean)(pfn_t pfn);
  45 EXPORT_SYMBOL(kvm_mips_release_pfn_clean);
  46
  47 bool (*kvm_mips_is_error_pfn)(pfn_t pfn);
  48 EXPORT_SYMBOL(kvm_mips_is_error_pfn);
  49
  50 uint32_t kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
  51 {
  52         return vcpu->arch.guest_kernel_asid[smp_processor_id()] & ASID_MASK;
  53 }
  54
  55 uint32_t kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
  56 {
  57         return vcpu->arch.guest_user_asid[smp_processor_id()] & ASID_MASK;
  58 }
  59
  60 inline uint32_t kvm_mips_get_commpage_asid(struct kvm_vcpu *vcpu)
  61 {
  62         return vcpu->kvm->arch.commpage_tlb;
  63 }
  64
  65 /* Structure defining an tlb entry data set. */
  66
  67 void kvm_mips_dump_host_tlbs(void)
  68 {
  69         unsigned long old_entryhi;
  70         unsigned long old_pagemask;
  71         struct kvm_mips_tlb tlb;
  72         unsigned long flags;
  73         int i;
  74
  75         local_irq_save(flags);
  76
  77         old_entryhi = read_c0_entryhi();
  78         old_pagemask = read_c0_pagemask();
  79
  80         kvm_info("HOST TLBs:\n");
  81         kvm_info("ASID: %#lx\n", read_c0_entryhi() & ASID_MASK);
  82
  83         for (i = 0; i < current_cpu_data.tlbsize; i++) {
  84                 write_c0_index(i);
  85                 mtc0_tlbw_hazard();
  86
  87                 tlb_read();
  88                 tlbw_use_hazard();
  89
  90                 tlb.tlb_hi = read_c0_entryhi();
  91                 tlb.tlb_lo0 = read_c0_entrylo0();
  92                 tlb.tlb_lo1 = read_c0_entrylo1();
  93                 tlb.tlb_mask = read_c0_pagemask();
  94
  95                 kvm_info("TLB%c%3d Hi 0x%08lx ",
  96                          (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
  97                          i, tlb.tlb_hi);
  98                 kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ",
  99                          (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0),
 100                          (tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ',
 101                          (tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ',
 102                          (tlb.tlb_lo0 >> 3) & 7);
 103                 kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n",
 104                          (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1),
 105                          (tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ',
 106                          (tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ',
 107                          (tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask);
 108         }
 109         write_c0_entryhi(old_entryhi);
 110         write_c0_pagemask(old_pagemask);
 111         mtc0_tlbw_hazard();
 112         local_irq_restore(flags);
 113 }
 114 EXPORT_SYMBOL(kvm_mips_dump_host_tlbs);
 115
 116 void kvm_mips_dump_guest_tlbs(struct kvm_vcpu *vcpu)
 117 {
 118         struct mips_coproc *cop0 = vcpu->arch.cop0;
 119         struct kvm_mips_tlb tlb;
 120         int i;
 121
 122         kvm_info("Guest TLBs:\n");
 123         kvm_info("Guest EntryHi: %#lx\n", kvm_read_c0_guest_entryhi(cop0));
 124
 125         for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
 126                 tlb = vcpu->arch.guest_tlb[i];
 127                 kvm_info("TLB%c%3d Hi 0x%08lx ",
 128                          (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
 129                          i, tlb.tlb_hi);
 130                 kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ",
 131                          (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0),
 132                          (tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ',
 133                          (tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ',
 134                          (tlb.tlb_lo0 >> 3) & 7);
 135                 kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n",
 136                          (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1),
 137                          (tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ',
 138                          (tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ',
 139                          (tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask);
 140         }
 141 }
 142 EXPORT_SYMBOL(kvm_mips_dump_guest_tlbs);
 143
 144 static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
 145 {
 146         int srcu_idx, err = 0;
 147         pfn_t pfn;
 148
 149         if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
 150                 return 0;
 151
 152         srcu_idx = srcu_read_lock(&kvm->srcu);
 153         pfn = kvm_mips_gfn_to_pfn(kvm, gfn);
 154
 155         if (kvm_mips_is_error_pfn(pfn)) {
 156                 kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn);
 157                 err = -EFAULT;
 158                 goto out;
 159         }
 160
 161         kvm->arch.guest_pmap[gfn] = pfn;
 162 out:
 163         srcu_read_unlock(&kvm->srcu, srcu_idx);
 164         return err;
 165 }
 166
 167 /* Translate guest KSEG0 addresses to Host PA */
 168 unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
 169                                                     unsigned long gva)
 170 {
 171         gfn_t gfn;
 172         uint32_t offset = gva & ~PAGE_MASK;
 173         struct kvm *kvm = vcpu->kvm;
 174
 175         if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
 176                 kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
 177                         __builtin_return_address(0), gva);
 178                 return KVM_INVALID_PAGE;
 179         }
 180
 181         gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);
 182
 183         if (gfn >= kvm->arch.guest_pmap_npages) {
 184                 kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
 185                         gva);
 186                 return KVM_INVALID_PAGE;
 187         }
 188
 189         if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
 190                 return KVM_INVALID_ADDR;
 191
 192         return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
 193 }
 194 EXPORT_SYMBOL(kvm_mips_translate_guest_kseg0_to_hpa);
 195
 196 /* XXXKYMA: Must be called with interrupts disabled */
 197 /* set flush_dcache_mask == 0 if no dcache flush required */
 198 int kvm_mips_host_tlb_write(struct kvm_vcpu *vcpu, unsigned long entryhi,
 199                             unsigned long entrylo0, unsigned long entrylo1,
 200                             int flush_dcache_mask)
 201 {
 202         unsigned long flags;
 203         unsigned long old_entryhi;
 204         int idx;
 205
 206         local_irq_save(flags);
 207
 208         old_entryhi = read_c0_entryhi();
 209         write_c0_entryhi(entryhi);
 210         mtc0_tlbw_hazard();
 211
 212         tlb_probe();
 213         tlb_probe_hazard();
 214         idx = read_c0_index();
 215
 216         if (idx > current_cpu_data.tlbsize) {
 217                 kvm_err("%s: Invalid Index: %d\n", __func__, idx);
 218                 kvm_mips_dump_host_tlbs();
 219                 return -1;
 220         }
 221
 222         write_c0_entrylo0(entrylo0);
 223         write_c0_entrylo1(entrylo1);
 224         mtc0_tlbw_hazard();
 225
 226         if (idx < 0)
 227                 tlb_write_random();
 228         else
 229                 tlb_write_indexed();
 230         tlbw_use_hazard();
 231
 232         kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0(R): 0x%08lx, entrylo1(R): 0x%08lx\n",
 233                   vcpu->arch.pc, idx, read_c0_entryhi(),
 234                   read_c0_entrylo0(), read_c0_entrylo1());
 235
 236         /* Flush D-cache */
 237         if (flush_dcache_mask) {
 238                 if (entrylo0 & MIPS3_PG_V) {
 239                         ++vcpu->stat.flush_dcache_exits;
 240                         flush_data_cache_page((entryhi & VPN2_MASK) &
 241                                               ~flush_dcache_mask);
 242                 }
 243                 if (entrylo1 & MIPS3_PG_V) {
 244                         ++vcpu->stat.flush_dcache_exits;
 245                         flush_data_cache_page(((entryhi & VPN2_MASK) &
 246                                                ~flush_dcache_mask) |
 247                                               (0x1 << PAGE_SHIFT));
 248                 }
 249         }
 250
 251         /* Restore old ASID */
 252         write_c0_entryhi(old_entryhi);
 253         mtc0_tlbw_hazard();
 254         tlbw_use_hazard();
 255         local_irq_restore(flags);
 256         return 0;
 257 }
 258
 259 /* XXXKYMA: Must be called with interrupts disabled */
 260 int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr,
 261                                     struct kvm_vcpu *vcpu)
 262 {
 263         gfn_t gfn;
 264         pfn_t pfn0, pfn1;
 265         unsigned long vaddr = 0;
 266         unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
 267         int even;
 268         struct kvm *kvm = vcpu->kvm;
 269         const int flush_dcache_mask = 0;
 270
 271         if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) {
 272                 kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr);
 273                 kvm_mips_dump_host_tlbs();
 274                 return -1;
 275         }
 276
 277         gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT);
 278         if (gfn >= kvm->arch.guest_pmap_npages) {
 279                 kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__,
 280                         gfn, badvaddr);
 281                 kvm_mips_dump_host_tlbs();
 282                 return -1;
 283         }
 284         even = !(gfn & 0x1);
 285         vaddr = badvaddr & (PAGE_MASK << 1);
 286
 287         if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
 288                 return -1;
 289
 290         if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0)
 291                 return -1;
 292
 293         if (even) {
 294                 pfn0 = kvm->arch.guest_pmap[gfn];
 295                 pfn1 = kvm->arch.guest_pmap[gfn ^ 0x1];
 296         } else {
 297                 pfn0 = kvm->arch.guest_pmap[gfn ^ 0x1];
 298                 pfn1 = kvm->arch.guest_pmap[gfn];
 299         }
 300
 301         entryhi = (vaddr | kvm_mips_get_kernel_asid(vcpu));
 302         entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) |
 303                    (1 << 2) | (0x1 << 1);
 304         entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | (0x3 << 3) |
 305                    (1 << 2) | (0x1 << 1);
 306
 307         return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
 308                                        flush_dcache_mask);
 309 }
 310 EXPORT_SYMBOL(kvm_mips_handle_kseg0_tlb_fault);
 311
 312 int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr,
 313         struct kvm_vcpu *vcpu)
 314 {
 315         pfn_t pfn0, pfn1;
 316         unsigned long flags, old_entryhi = 0, vaddr = 0;
 317         unsigned long entrylo0 = 0, entrylo1 = 0;
 318
 319         pfn0 = CPHYSADDR(vcpu->arch.kseg0_commpage) >> PAGE_SHIFT;
 320         pfn1 = 0;
 321         entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) |
 322                    (1 << 2) | (0x1 << 1);
 323         entrylo1 = 0;
 324
 325         local_irq_save(flags);
 326
 327         old_entryhi = read_c0_entryhi();
 328         vaddr = badvaddr & (PAGE_MASK << 1);
 329         write_c0_entryhi(vaddr | kvm_mips_get_kernel_asid(vcpu));
 330         mtc0_tlbw_hazard();
 331         write_c0_entrylo0(entrylo0);
 332         mtc0_tlbw_hazard();
 333         write_c0_entrylo1(entrylo1);
 334         mtc0_tlbw_hazard();
 335         write_c0_index(kvm_mips_get_commpage_asid(vcpu));
 336         mtc0_tlbw_hazard();
 337         tlb_write_indexed();
 338         mtc0_tlbw_hazard();
 339         tlbw_use_hazard();
 340
 341         kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0 (R): 0x%08lx, entrylo1(R): 0x%08lx\n",
 342                   vcpu->arch.pc, read_c0_index(), read_c0_entryhi(),
 343                   read_c0_entrylo0(), read_c0_entrylo1());
 344
 345         /* Restore old ASID */
 346         write_c0_entryhi(old_entryhi);
 347         mtc0_tlbw_hazard();
 348         tlbw_use_hazard();
 349         local_irq_restore(flags);
 350
 351         return 0;
 352 }
 353 EXPORT_SYMBOL(kvm_mips_handle_commpage_tlb_fault);
 354
 355 int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu,
 356                                          struct kvm_mips_tlb *tlb,
 357                                          unsigned long *hpa0,
 358                                          unsigned long *hpa1)
 359 {
 360         unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
 361         struct kvm *kvm = vcpu->kvm;
 362         pfn_t pfn0, pfn1;
 363
 364         if ((tlb->tlb_hi & VPN2_MASK) == 0) {
 365                 pfn0 = 0;
 366                 pfn1 = 0;
 367         } else {
 368                 if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0)
 369                                            >> PAGE_SHIFT) < 0)
 370                         return -1;
 371
 372                 if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1)
 373                                            >> PAGE_SHIFT) < 0)
 374                         return -1;
 375
 376                 pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0)
 377                                             >> PAGE_SHIFT];
 378                 pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1)
 379                                             >> PAGE_SHIFT];
 380         }
 381
 382         if (hpa0)
 383                 *hpa0 = pfn0 << PAGE_SHIFT;
 384
 385         if (hpa1)
 386                 *hpa1 = pfn1 << PAGE_SHIFT;
 387
 388         /* Get attributes from the Guest TLB */
 389         entryhi = (tlb->tlb_hi & VPN2_MASK) | (KVM_GUEST_KERNEL_MODE(vcpu) ?
 390                                                kvm_mips_get_kernel_asid(vcpu) :
 391                                                kvm_mips_get_user_asid(vcpu));
 392         entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) |
 393                    (tlb->tlb_lo0 & MIPS3_PG_D) | (tlb->tlb_lo0 & MIPS3_PG_V);
 394         entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | (0x3 << 3) |
 395                    (tlb->tlb_lo1 & MIPS3_PG_D) | (tlb->tlb_lo1 & MIPS3_PG_V);
 396
 397         kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
 398                   tlb->tlb_lo0, tlb->tlb_lo1);
 399
 400         return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
 401                                        tlb->tlb_mask);
 402 }
 403 EXPORT_SYMBOL(kvm_mips_handle_mapped_seg_tlb_fault);
 404
 405 int kvm_mips_guest_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long entryhi)
 406 {
 407         int i;
 408         int index = -1;
 409         struct kvm_mips_tlb *tlb = vcpu->arch.guest_tlb;
 410
 411         for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
 412                 if (TLB_HI_VPN2_HIT(tlb[i], entryhi) &&
 413                     TLB_HI_ASID_HIT(tlb[i], entryhi)) {
 414                         index = i;
 415                         break;
 416                 }
 417         }
 418
 419         kvm_debug("%s: entryhi: %#lx, index: %d lo0: %#lx, lo1: %#lx\n",
 420                   __func__, entryhi, index, tlb[i].tlb_lo0, tlb[i].tlb_lo1);
 421
 422         return index;
 423 }
 424 EXPORT_SYMBOL(kvm_mips_guest_tlb_lookup);
 425
 426 int kvm_mips_host_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long vaddr)
 427 {
 428         unsigned long old_entryhi, flags;
 429         int idx;
 430
 431         local_irq_save(flags);
 432
 433         old_entryhi = read_c0_entryhi();
 434
 435         if (KVM_GUEST_KERNEL_MODE(vcpu))
 436                 write_c0_entryhi((vaddr & VPN2_MASK) |
 437                                  kvm_mips_get_kernel_asid(vcpu));
 438         else {
 439                 write_c0_entryhi((vaddr & VPN2_MASK) |
 440                                  kvm_mips_get_user_asid(vcpu));
 441         }
 442
 443         mtc0_tlbw_hazard();
 444
 445         tlb_probe();
 446         tlb_probe_hazard();
 447         idx = read_c0_index();
 448
 449         /* Restore old ASID */
 450         write_c0_entryhi(old_entryhi);
 451         mtc0_tlbw_hazard();
 452         tlbw_use_hazard();
 453
 454         local_irq_restore(flags);
 455
 456         kvm_debug("Host TLB lookup, %#lx, idx: %2d\n", vaddr, idx);
 457
 458         return idx;
 459 }
 460 EXPORT_SYMBOL(kvm_mips_host_tlb_lookup);
 461
 462 int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va)
 463 {
 464         int idx;
 465         unsigned long flags, old_entryhi;
 466
 467         local_irq_save(flags);
 468
 469         old_entryhi = read_c0_entryhi();
 470
 471         write_c0_entryhi((va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu));
 472         mtc0_tlbw_hazard();
 473
 474         tlb_probe();
 475         tlb_probe_hazard();
 476         idx = read_c0_index();
 477
 478         if (idx >= current_cpu_data.tlbsize)
 479                 BUG();
 480
 481         if (idx > 0) {
 482                 write_c0_entryhi(UNIQUE_ENTRYHI(idx));
 483                 mtc0_tlbw_hazard();
 484
 485                 write_c0_entrylo0(0);
 486                 mtc0_tlbw_hazard();
 487
 488                 write_c0_entrylo1(0);
 489                 mtc0_tlbw_hazard();
 490
 491                 tlb_write_indexed();
 492                 mtc0_tlbw_hazard();
 493         }
 494
 495         write_c0_entryhi(old_entryhi);
 496         mtc0_tlbw_hazard();
 497         tlbw_use_hazard();
 498
 499         local_irq_restore(flags);
 500
 501         if (idx > 0)
 502                 kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__,
 503                           (va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu), idx);
 504
 505         return 0;
 506 }
 507 EXPORT_SYMBOL(kvm_mips_host_tlb_inv);
 508
 509 /* XXXKYMA: Fix Guest USER/KERNEL no longer share the same ASID */
 510 int kvm_mips_host_tlb_inv_index(struct kvm_vcpu *vcpu, int index)
 511 {
 512         unsigned long flags, old_entryhi;
 513
 514         if (index >= current_cpu_data.tlbsize)
 515                 BUG();
 516
 517         local_irq_save(flags);
 518
 519         old_entryhi = read_c0_entryhi();
 520
 521         write_c0_entryhi(UNIQUE_ENTRYHI(index));
 522         mtc0_tlbw_hazard();
 523
 524         write_c0_index(index);
 525         mtc0_tlbw_hazard();
 526
 527         write_c0_entrylo0(0);
 528         mtc0_tlbw_hazard();
 529
 530         write_c0_entrylo1(0);
 531         mtc0_tlbw_hazard();
 532
 533         tlb_write_indexed();
 534         mtc0_tlbw_hazard();
 535         tlbw_use_hazard();
 536
 537         write_c0_entryhi(old_entryhi);
 538         mtc0_tlbw_hazard();
 539         tlbw_use_hazard();
 540
 541         local_irq_restore(flags);
 542
 543         return 0;
 544 }
 545
 546 void kvm_mips_flush_host_tlb(int skip_kseg0)
 547 {
 548         unsigned long flags;
 549         unsigned long old_entryhi, entryhi;
 550         unsigned long old_pagemask;
 551         int entry = 0;
 552         int maxentry = current_cpu_data.tlbsize;
 553
 554         local_irq_save(flags);
 555
 556         old_entryhi = read_c0_entryhi();
 557         old_pagemask = read_c0_pagemask();
 558
 559         /* Blast 'em all away. */
 560         for (entry = 0; entry < maxentry; entry++) {
 561                 write_c0_index(entry);
 562                 mtc0_tlbw_hazard();
 563
 564                 if (skip_kseg0) {
 565                         tlb_read();
 566                         tlbw_use_hazard();
 567
 568                         entryhi = read_c0_entryhi();
 569
 570                         /* Don't blow away guest kernel entries */
 571                         if (KVM_GUEST_KSEGX(entryhi) == KVM_GUEST_KSEG0)
 572                                 continue;
 573                 }
 574
 575                 /* Make sure all entries differ. */
 576                 write_c0_entryhi(UNIQUE_ENTRYHI(entry));
 577                 mtc0_tlbw_hazard();
 578                 write_c0_entrylo0(0);
 579                 mtc0_tlbw_hazard();
 580                 write_c0_entrylo1(0);
 581                 mtc0_tlbw_hazard();
 582
 583                 tlb_write_indexed();
 584                 mtc0_tlbw_hazard();
 585         }
 586
 587         tlbw_use_hazard();
 588
 589         write_c0_entryhi(old_entryhi);
 590         write_c0_pagemask(old_pagemask);
 591         mtc0_tlbw_hazard();
 592         tlbw_use_hazard();
 593
 594         local_irq_restore(flags);
 595 }
 596 EXPORT_SYMBOL(kvm_mips_flush_host_tlb);
 597
 598 void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
 599                              struct kvm_vcpu *vcpu)
 600 {
 601         unsigned long asid = asid_cache(cpu);
 602
 603         asid += ASID_INC;
 604         if (!(asid & ASID_MASK)) {
 605                 if (cpu_has_vtag_icache)
 606                         flush_icache_all();
 607
 608                 kvm_local_flush_tlb_all();      /* start new asid cycle */
 609
 610                 if (!asid)      /* fix version if needed */
 611                         asid = ASID_FIRST_VERSION;
 612         }
 613
 614         cpu_context(cpu, mm) = asid_cache(cpu) = asid;
 615 }
 616
 617 void kvm_local_flush_tlb_all(void)
 618 {
 619         unsigned long flags;
 620         unsigned long old_ctx;
 621         int entry = 0;
 622
 623         local_irq_save(flags);
 624         /* Save old context and create impossible VPN2 value */
 625         old_ctx = read_c0_entryhi();
 626         write_c0_entrylo0(0);
 627         write_c0_entrylo1(0);
 628
 629         /* Blast 'em all away. */
 630         while (entry < current_cpu_data.tlbsize) {
 631                 /* Make sure all entries differ. */
 632                 write_c0_entryhi(UNIQUE_ENTRYHI(entry));
 633                 write_c0_index(entry);
 634                 mtc0_tlbw_hazard();
 635                 tlb_write_indexed();
 636                 entry++;
 637         }
 638         tlbw_use_hazard();
 639         write_c0_entryhi(old_ctx);
 640         mtc0_tlbw_hazard();
 641
 642         local_irq_restore(flags);
 643 }
 644 EXPORT_SYMBOL(kvm_local_flush_tlb_all);
 645
 646 /**
 647  * kvm_mips_migrate_count() - Migrate timer.
 648  * @vcpu:       Virtual CPU.
 649  *
 650  * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
 651  * if it was running prior to being cancelled.
 652  *
 653  * Must be called when the VCPU is migrated to a different CPU to ensure that
 654  * timer expiry during guest execution interrupts the guest and causes the
 655  * interrupt to be delivered in a timely manner.
 656  */
 657 static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
 658 {
 659         if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
 660                 hrtimer_restart(&vcpu->arch.comparecount_timer);
 661 }
 662
 663 /* Restore ASID once we are scheduled back after preemption */
 664 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 665 {
 666         unsigned long flags;
 667         int newasid = 0;
 668
 669         kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);
 670
 671         /* Alocate new kernel and user ASIDs if needed */
 672
 673         local_irq_save(flags);
 674
 675         if (((vcpu->arch.
 676               guest_kernel_asid[cpu] ^ asid_cache(cpu)) & ASID_VERSION_MASK)) {
 677                 kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
 678                 vcpu->arch.guest_kernel_asid[cpu] =
 679                     vcpu->arch.guest_kernel_mm.context.asid[cpu];
 680                 kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
 681                 vcpu->arch.guest_user_asid[cpu] =
 682                     vcpu->arch.guest_user_mm.context.asid[cpu];
 683                 newasid++;
 684
 685                 kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
 686                           cpu_context(cpu, current->mm));
 687                 kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
 688                           cpu, vcpu->arch.guest_kernel_asid[cpu]);
 689                 kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
 690                           vcpu->arch.guest_user_asid[cpu]);
 691         }
 692
 693         if (vcpu->arch.last_sched_cpu != cpu) {
 694                 kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
 695                           vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
 696                 /*
 697                  * Migrate the timer interrupt to the current CPU so that it
 698                  * always interrupts the guest and synchronously triggers a
 699                  * guest timer interrupt.
 700                  */
 701                 kvm_mips_migrate_count(vcpu);
 702         }
 703
 704         if (!newasid) {
 705                 /*
 706                  * If we preempted while the guest was executing, then reload
 707                  * the pre-empted ASID
 708                  */
 709                 if (current->flags & PF_VCPU) {
 710                         write_c0_entryhi(vcpu->arch.
 711                                          preempt_entryhi & ASID_MASK);
 712                         ehb();
 713                 }
 714         } else {
 715                 /* New ASIDs were allocated for the VM */
 716
 717                 /*
 718                  * Were we in guest context? If so then the pre-empted ASID is
 719                  * no longer valid, we need to set it to what it should be based
 720                  * on the mode of the Guest (Kernel/User)
 721                  */
 722                 if (current->flags & PF_VCPU) {
 723                         if (KVM_GUEST_KERNEL_MODE(vcpu))
 724                                 write_c0_entryhi(vcpu->arch.
 725                                                  guest_kernel_asid[cpu] &
 726                                                  ASID_MASK);
 727                         else
 728                                 write_c0_entryhi(vcpu->arch.
 729                                                  guest_user_asid[cpu] &
 730                                                  ASID_MASK);
 731                         ehb();
 732                 }
 733         }
 734
 735         local_irq_restore(flags);
 736
 737 }
 738 EXPORT_SYMBOL(kvm_arch_vcpu_load);
 739
 740 /* ASID can change if another task is scheduled during preemption */
 741 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 742 {
 743         unsigned long flags;
 744         uint32_t cpu;
 745
 746         local_irq_save(flags);
 747
 748         cpu = smp_processor_id();
 749
 750         vcpu->arch.preempt_entryhi = read_c0_entryhi();
 751         vcpu->arch.last_sched_cpu = cpu;
 752
 753         if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
 754              ASID_VERSION_MASK)) {
 755                 kvm_debug("%s: Dropping MMU Context:  %#lx\n", __func__,
 756                           cpu_context(cpu, current->mm));
 757                 drop_mmu_context(current->mm, cpu);
 758         }
 759         write_c0_entryhi(cpu_asid(cpu, current->mm));
 760         ehb();
 761
 762         local_irq_restore(flags);
 763 }
 764 EXPORT_SYMBOL(kvm_arch_vcpu_put);
 765
 766 uint32_t kvm_get_inst(uint32_t *opc, struct kvm_vcpu *vcpu)
 767 {
 768         struct mips_coproc *cop0 = vcpu->arch.cop0;
 769         unsigned long paddr, flags, vpn2, asid;
 770         uint32_t inst;
 771         int index;
 772
 773         if (KVM_GUEST_KSEGX((unsigned long) opc) < KVM_GUEST_KSEG0 ||
 774             KVM_GUEST_KSEGX((unsigned long) opc) == KVM_GUEST_KSEG23) {
 775                 local_irq_save(flags);
 776                 index = kvm_mips_host_tlb_lookup(vcpu, (unsigned long) opc);
 777                 if (index >= 0) {
 778                         inst = *(opc);
 779                 } else {
 780                         vpn2 = (unsigned long) opc & VPN2_MASK;
 781                         asid = kvm_read_c0_guest_entryhi(cop0) & ASID_MASK;
 782                         index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 | asid);
 783                         if (index < 0) {
 784                                 kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
 785                                         __func__, opc, vcpu, read_c0_entryhi());
 786                                 kvm_mips_dump_host_tlbs();
 787                                 local_irq_restore(flags);
 788                                 return KVM_INVALID_INST;
 789                         }
 790                         kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
 791                                                              &vcpu->arch.
 792                                                              guest_tlb[index],
 793                                                              NULL, NULL);
 794                         inst = *(opc);
 795                 }
 796                 local_irq_restore(flags);
 797         } else if (KVM_GUEST_KSEGX(opc) == KVM_GUEST_KSEG0) {
 798                 paddr =
 799                     kvm_mips_translate_guest_kseg0_to_hpa(vcpu,
 800                                                           (unsigned long) opc);
 801                 inst = *(uint32_t *) CKSEG0ADDR(paddr);
 802         } else {
 803                 kvm_err("%s: illegal address: %p\n", __func__, opc);
 804                 return KVM_INVALID_INST;
 805         }
 806
 807         return inst;
 808 }
 809 EXPORT_SYMBOL(kvm_get_inst);