1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright IBM Corporation, 2018 4 * Authors Suraj Jitindar Singh <sjitindarsingh@gmail.com> 5 * Paul Mackerras <paulus@ozlabs.org> 6 * 7 * Description: KVM functions specific to running nested KVM-HV guests 8 * on Book3S processors (specifically POWER9 and later). 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/kvm_host.h> 13 #include <linux/llist.h> 14 #include <linux/pgtable.h> 15 16 #include <asm/kvm_ppc.h> 17 #include <asm/kvm_book3s.h> 18 #include <asm/mmu.h> 19 #include <asm/pgalloc.h> 20 #include <asm/pte-walk.h> 21 #include <asm/reg.h> 22 23 static struct patb_entry *pseries_partition_tb; 24 25 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp); 26 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free); 27 28 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) 29 { 30 struct kvmppc_vcore *vc = vcpu->arch.vcore; 31 32 hr->pcr = vc->pcr | PCR_MASK; 33 hr->dpdes = vc->dpdes; 34 hr->hfscr = vcpu->arch.hfscr; 35 hr->tb_offset = vc->tb_offset; 36 hr->dawr0 = vcpu->arch.dawr; 37 hr->dawrx0 = vcpu->arch.dawrx; 38 hr->ciabr = vcpu->arch.ciabr; 39 hr->purr = vcpu->arch.purr; 40 hr->spurr = vcpu->arch.spurr; 41 hr->ic = vcpu->arch.ic; 42 hr->vtb = vc->vtb; 43 hr->srr0 = vcpu->arch.shregs.srr0; 44 hr->srr1 = vcpu->arch.shregs.srr1; 45 hr->sprg[0] = vcpu->arch.shregs.sprg0; 46 hr->sprg[1] = vcpu->arch.shregs.sprg1; 47 hr->sprg[2] = vcpu->arch.shregs.sprg2; 48 hr->sprg[3] = vcpu->arch.shregs.sprg3; 49 hr->pidr = vcpu->arch.pid; 50 hr->cfar = vcpu->arch.cfar; 51 hr->ppr = vcpu->arch.ppr; 52 } 53 54 static void byteswap_pt_regs(struct pt_regs *regs) 55 { 56 unsigned long *addr = (unsigned long *) regs; 57 58 for (; addr < ((unsigned long *) (regs + 1)); addr++) 59 *addr = swab64(*addr); 60 } 61 62 static void byteswap_hv_regs(struct hv_guest_state *hr) 63 { 64 hr->version = swab64(hr->version); 65 hr->lpid = swab32(hr->lpid); 66 hr->vcpu_token = swab32(hr->vcpu_token); 67 hr->lpcr = swab64(hr->lpcr); 68 hr->pcr = swab64(hr->pcr) | PCR_MASK; 69 hr->amor = swab64(hr->amor); 70 hr->dpdes = swab64(hr->dpdes); 71 hr->hfscr = swab64(hr->hfscr); 72 hr->tb_offset = swab64(hr->tb_offset); 73 hr->dawr0 = swab64(hr->dawr0); 74 hr->dawrx0 = swab64(hr->dawrx0); 75 hr->ciabr = swab64(hr->ciabr); 76 hr->hdec_expiry = swab64(hr->hdec_expiry); 77 hr->purr = swab64(hr->purr); 78 hr->spurr = swab64(hr->spurr); 79 hr->ic = swab64(hr->ic); 80 hr->vtb = swab64(hr->vtb); 81 hr->hdar = swab64(hr->hdar); 82 hr->hdsisr = swab64(hr->hdsisr); 83 hr->heir = swab64(hr->heir); 84 hr->asdr = swab64(hr->asdr); 85 hr->srr0 = swab64(hr->srr0); 86 hr->srr1 = swab64(hr->srr1); 87 hr->sprg[0] = swab64(hr->sprg[0]); 88 hr->sprg[1] = swab64(hr->sprg[1]); 89 hr->sprg[2] = swab64(hr->sprg[2]); 90 hr->sprg[3] = swab64(hr->sprg[3]); 91 hr->pidr = swab64(hr->pidr); 92 hr->cfar = swab64(hr->cfar); 93 hr->ppr = swab64(hr->ppr); 94 } 95 96 static void save_hv_return_state(struct kvm_vcpu *vcpu, int trap, 97 struct hv_guest_state *hr) 98 { 99 struct kvmppc_vcore *vc = vcpu->arch.vcore; 100 101 hr->dpdes = vc->dpdes; 102 hr->hfscr = vcpu->arch.hfscr; 103 hr->purr = vcpu->arch.purr; 104 hr->spurr = vcpu->arch.spurr; 105 hr->ic = vcpu->arch.ic; 106 hr->vtb = vc->vtb; 107 hr->srr0 = vcpu->arch.shregs.srr0; 108 hr->srr1 = vcpu->arch.shregs.srr1; 109 hr->sprg[0] = vcpu->arch.shregs.sprg0; 110 hr->sprg[1] = vcpu->arch.shregs.sprg1; 111 hr->sprg[2] = vcpu->arch.shregs.sprg2; 112 hr->sprg[3] = vcpu->arch.shregs.sprg3; 113 hr->pidr = vcpu->arch.pid; 114 hr->cfar = vcpu->arch.cfar; 115 hr->ppr = vcpu->arch.ppr; 116 switch (trap) { 117 case BOOK3S_INTERRUPT_H_DATA_STORAGE: 118 hr->hdar = vcpu->arch.fault_dar; 119 hr->hdsisr = vcpu->arch.fault_dsisr; 120 hr->asdr = vcpu->arch.fault_gpa; 121 break; 122 case BOOK3S_INTERRUPT_H_INST_STORAGE: 123 hr->asdr = vcpu->arch.fault_gpa; 124 break; 125 case BOOK3S_INTERRUPT_H_EMUL_ASSIST: 126 hr->heir = vcpu->arch.emul_inst; 127 break; 128 } 129 } 130 131 static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) 132 { 133 /* 134 * Don't let L1 enable features for L2 which we've disabled for L1, 135 * but preserve the interrupt cause field. 136 */ 137 hr->hfscr &= (HFSCR_INTR_CAUSE | vcpu->arch.hfscr); 138 139 /* Don't let data address watchpoint match in hypervisor state */ 140 hr->dawrx0 &= ~DAWRX_HYP; 141 142 /* Don't let completed instruction address breakpt match in HV state */ 143 if ((hr->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER) 144 hr->ciabr &= ~CIABR_PRIV; 145 } 146 147 static void restore_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) 148 { 149 struct kvmppc_vcore *vc = vcpu->arch.vcore; 150 151 vc->pcr = hr->pcr | PCR_MASK; 152 vc->dpdes = hr->dpdes; 153 vcpu->arch.hfscr = hr->hfscr; 154 vcpu->arch.dawr = hr->dawr0; 155 vcpu->arch.dawrx = hr->dawrx0; 156 vcpu->arch.ciabr = hr->ciabr; 157 vcpu->arch.purr = hr->purr; 158 vcpu->arch.spurr = hr->spurr; 159 vcpu->arch.ic = hr->ic; 160 vc->vtb = hr->vtb; 161 vcpu->arch.shregs.srr0 = hr->srr0; 162 vcpu->arch.shregs.srr1 = hr->srr1; 163 vcpu->arch.shregs.sprg0 = hr->sprg[0]; 164 vcpu->arch.shregs.sprg1 = hr->sprg[1]; 165 vcpu->arch.shregs.sprg2 = hr->sprg[2]; 166 vcpu->arch.shregs.sprg3 = hr->sprg[3]; 167 vcpu->arch.pid = hr->pidr; 168 vcpu->arch.cfar = hr->cfar; 169 vcpu->arch.ppr = hr->ppr; 170 } 171 172 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu, 173 struct hv_guest_state *hr) 174 { 175 struct kvmppc_vcore *vc = vcpu->arch.vcore; 176 177 vc->dpdes = hr->dpdes; 178 vcpu->arch.hfscr = hr->hfscr; 179 vcpu->arch.purr = hr->purr; 180 vcpu->arch.spurr = hr->spurr; 181 vcpu->arch.ic = hr->ic; 182 vc->vtb = hr->vtb; 183 vcpu->arch.fault_dar = hr->hdar; 184 vcpu->arch.fault_dsisr = hr->hdsisr; 185 vcpu->arch.fault_gpa = hr->asdr; 186 vcpu->arch.emul_inst = hr->heir; 187 vcpu->arch.shregs.srr0 = hr->srr0; 188 vcpu->arch.shregs.srr1 = hr->srr1; 189 vcpu->arch.shregs.sprg0 = hr->sprg[0]; 190 vcpu->arch.shregs.sprg1 = hr->sprg[1]; 191 vcpu->arch.shregs.sprg2 = hr->sprg[2]; 192 vcpu->arch.shregs.sprg3 = hr->sprg[3]; 193 vcpu->arch.pid = hr->pidr; 194 vcpu->arch.cfar = hr->cfar; 195 vcpu->arch.ppr = hr->ppr; 196 } 197 198 static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr) 199 { 200 /* No need to reflect the page fault to L1, we've handled it */ 201 vcpu->arch.trap = 0; 202 203 /* 204 * Since the L2 gprs have already been written back into L1 memory when 205 * we complete the mmio, store the L1 memory location of the L2 gpr 206 * being loaded into by the mmio so that the loaded value can be 207 * written there in kvmppc_complete_mmio_load() 208 */ 209 if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR) 210 && (vcpu->mmio_is_write == 0)) { 211 vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr + 212 offsetof(struct pt_regs, 213 gpr[vcpu->arch.io_gpr]); 214 vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR; 215 } 216 } 217 218 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu) 219 { 220 long int err, r; 221 struct kvm_nested_guest *l2; 222 struct pt_regs l2_regs, saved_l1_regs; 223 struct hv_guest_state l2_hv, saved_l1_hv; 224 struct kvmppc_vcore *vc = vcpu->arch.vcore; 225 u64 hv_ptr, regs_ptr; 226 u64 hdec_exp; 227 s64 delta_purr, delta_spurr, delta_ic, delta_vtb; 228 u64 mask; 229 unsigned long lpcr; 230 231 if (vcpu->kvm->arch.l1_ptcr == 0) 232 return H_NOT_AVAILABLE; 233 234 /* copy parameters in */ 235 hv_ptr = kvmppc_get_gpr(vcpu, 4); 236 regs_ptr = kvmppc_get_gpr(vcpu, 5); 237 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); 238 err = kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv, 239 sizeof(struct hv_guest_state)) || 240 kvm_vcpu_read_guest(vcpu, regs_ptr, &l2_regs, 241 sizeof(struct pt_regs)); 242 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); 243 if (err) 244 return H_PARAMETER; 245 246 if (kvmppc_need_byteswap(vcpu)) 247 byteswap_hv_regs(&l2_hv); 248 if (l2_hv.version != HV_GUEST_STATE_VERSION) 249 return H_P2; 250 251 if (kvmppc_need_byteswap(vcpu)) 252 byteswap_pt_regs(&l2_regs); 253 if (l2_hv.vcpu_token >= NR_CPUS) 254 return H_PARAMETER; 255 256 /* translate lpid */ 257 l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true); 258 if (!l2) 259 return H_PARAMETER; 260 if (!l2->l1_gr_to_hr) { 261 mutex_lock(&l2->tlb_lock); 262 kvmhv_update_ptbl_cache(l2); 263 mutex_unlock(&l2->tlb_lock); 264 } 265 266 /* save l1 values of things */ 267 vcpu->arch.regs.msr = vcpu->arch.shregs.msr; 268 saved_l1_regs = vcpu->arch.regs; 269 kvmhv_save_hv_regs(vcpu, &saved_l1_hv); 270 271 /* convert TB values/offsets to host (L0) values */ 272 hdec_exp = l2_hv.hdec_expiry - vc->tb_offset; 273 vc->tb_offset += l2_hv.tb_offset; 274 275 /* set L1 state to L2 state */ 276 vcpu->arch.nested = l2; 277 vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token; 278 vcpu->arch.regs = l2_regs; 279 vcpu->arch.shregs.msr = vcpu->arch.regs.msr; 280 mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD | 281 LPCR_LPES | LPCR_MER; 282 lpcr = (vc->lpcr & ~mask) | (l2_hv.lpcr & mask); 283 sanitise_hv_regs(vcpu, &l2_hv); 284 restore_hv_regs(vcpu, &l2_hv); 285 286 vcpu->arch.ret = RESUME_GUEST; 287 vcpu->arch.trap = 0; 288 do { 289 if (mftb() >= hdec_exp) { 290 vcpu->arch.trap = BOOK3S_INTERRUPT_HV_DECREMENTER; 291 r = RESUME_HOST; 292 break; 293 } 294 r = kvmhv_run_single_vcpu(vcpu, hdec_exp, lpcr); 295 } while (is_kvmppc_resume_guest(r)); 296 297 /* save L2 state for return */ 298 l2_regs = vcpu->arch.regs; 299 l2_regs.msr = vcpu->arch.shregs.msr; 300 delta_purr = vcpu->arch.purr - l2_hv.purr; 301 delta_spurr = vcpu->arch.spurr - l2_hv.spurr; 302 delta_ic = vcpu->arch.ic - l2_hv.ic; 303 delta_vtb = vc->vtb - l2_hv.vtb; 304 save_hv_return_state(vcpu, vcpu->arch.trap, &l2_hv); 305 306 /* restore L1 state */ 307 vcpu->arch.nested = NULL; 308 vcpu->arch.regs = saved_l1_regs; 309 vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK; 310 /* set L1 MSR TS field according to L2 transaction state */ 311 if (l2_regs.msr & MSR_TS_MASK) 312 vcpu->arch.shregs.msr |= MSR_TS_S; 313 vc->tb_offset = saved_l1_hv.tb_offset; 314 restore_hv_regs(vcpu, &saved_l1_hv); 315 vcpu->arch.purr += delta_purr; 316 vcpu->arch.spurr += delta_spurr; 317 vcpu->arch.ic += delta_ic; 318 vc->vtb += delta_vtb; 319 320 kvmhv_put_nested(l2); 321 322 /* copy l2_hv_state and regs back to guest */ 323 if (kvmppc_need_byteswap(vcpu)) { 324 byteswap_hv_regs(&l2_hv); 325 byteswap_pt_regs(&l2_regs); 326 } 327 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); 328 err = kvm_vcpu_write_guest(vcpu, hv_ptr, &l2_hv, 329 sizeof(struct hv_guest_state)) || 330 kvm_vcpu_write_guest(vcpu, regs_ptr, &l2_regs, 331 sizeof(struct pt_regs)); 332 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); 333 if (err) 334 return H_AUTHORITY; 335 336 if (r == -EINTR) 337 return H_INTERRUPT; 338 339 if (vcpu->mmio_needed) { 340 kvmhv_nested_mmio_needed(vcpu, regs_ptr); 341 return H_TOO_HARD; 342 } 343 344 return vcpu->arch.trap; 345 } 346 347 long kvmhv_nested_init(void) 348 { 349 long int ptb_order; 350 unsigned long ptcr; 351 long rc; 352 353 if (!kvmhv_on_pseries()) 354 return 0; 355 if (!radix_enabled()) 356 return -ENODEV; 357 358 /* find log base 2 of KVMPPC_NR_LPIDS, rounding up */ 359 ptb_order = __ilog2(KVMPPC_NR_LPIDS - 1) + 1; 360 if (ptb_order < 8) 361 ptb_order = 8; 362 pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order, 363 GFP_KERNEL); 364 if (!pseries_partition_tb) { 365 pr_err("kvm-hv: failed to allocated nested partition table\n"); 366 return -ENOMEM; 367 } 368 369 ptcr = __pa(pseries_partition_tb) | (ptb_order - 8); 370 rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr); 371 if (rc != H_SUCCESS) { 372 pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n", 373 rc); 374 kfree(pseries_partition_tb); 375 pseries_partition_tb = NULL; 376 return -ENODEV; 377 } 378 379 return 0; 380 } 381 382 void kvmhv_nested_exit(void) 383 { 384 /* 385 * N.B. the kvmhv_on_pseries() test is there because it enables 386 * the compiler to remove the call to plpar_hcall_norets() 387 * when CONFIG_PPC_PSERIES=n. 388 */ 389 if (kvmhv_on_pseries() && pseries_partition_tb) { 390 plpar_hcall_norets(H_SET_PARTITION_TABLE, 0); 391 kfree(pseries_partition_tb); 392 pseries_partition_tb = NULL; 393 } 394 } 395 396 static void kvmhv_flush_lpid(unsigned int lpid) 397 { 398 long rc; 399 400 if (!kvmhv_on_pseries()) { 401 radix__flush_all_lpid(lpid); 402 return; 403 } 404 405 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1), 406 lpid, TLBIEL_INVAL_SET_LPID); 407 if (rc) 408 pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc); 409 } 410 411 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1) 412 { 413 if (!kvmhv_on_pseries()) { 414 mmu_partition_table_set_entry(lpid, dw0, dw1, true); 415 return; 416 } 417 418 pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0); 419 pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1); 420 /* L0 will do the necessary barriers */ 421 kvmhv_flush_lpid(lpid); 422 } 423 424 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp) 425 { 426 unsigned long dw0; 427 428 dw0 = PATB_HR | radix__get_tree_size() | 429 __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE; 430 kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table); 431 } 432 433 void kvmhv_vm_nested_init(struct kvm *kvm) 434 { 435 kvm->arch.max_nested_lpid = -1; 436 } 437 438 /* 439 * Handle the H_SET_PARTITION_TABLE hcall. 440 * r4 = guest real address of partition table + log_2(size) - 12 441 * (formatted as for the PTCR). 442 */ 443 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu) 444 { 445 struct kvm *kvm = vcpu->kvm; 446 unsigned long ptcr = kvmppc_get_gpr(vcpu, 4); 447 int srcu_idx; 448 long ret = H_SUCCESS; 449 450 srcu_idx = srcu_read_lock(&kvm->srcu); 451 /* 452 * Limit the partition table to 4096 entries (because that's what 453 * hardware supports), and check the base address. 454 */ 455 if ((ptcr & PRTS_MASK) > 12 - 8 || 456 !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT)) 457 ret = H_PARAMETER; 458 srcu_read_unlock(&kvm->srcu, srcu_idx); 459 if (ret == H_SUCCESS) 460 kvm->arch.l1_ptcr = ptcr; 461 return ret; 462 } 463 464 /* 465 * Handle the H_COPY_TOFROM_GUEST hcall. 466 * r4 = L1 lpid of nested guest 467 * r5 = pid 468 * r6 = eaddr to access 469 * r7 = to buffer (L1 gpa) 470 * r8 = from buffer (L1 gpa) 471 * r9 = n bytes to copy 472 */ 473 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu) 474 { 475 struct kvm_nested_guest *gp; 476 int l1_lpid = kvmppc_get_gpr(vcpu, 4); 477 int pid = kvmppc_get_gpr(vcpu, 5); 478 gva_t eaddr = kvmppc_get_gpr(vcpu, 6); 479 gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7); 480 gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8); 481 void *buf; 482 unsigned long n = kvmppc_get_gpr(vcpu, 9); 483 bool is_load = !!gp_to; 484 long rc; 485 486 if (gp_to && gp_from) /* One must be NULL to determine the direction */ 487 return H_PARAMETER; 488 489 if (eaddr & (0xFFFUL << 52)) 490 return H_PARAMETER; 491 492 buf = kzalloc(n, GFP_KERNEL); 493 if (!buf) 494 return H_NO_MEM; 495 496 gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false); 497 if (!gp) { 498 rc = H_PARAMETER; 499 goto out_free; 500 } 501 502 mutex_lock(&gp->tlb_lock); 503 504 if (is_load) { 505 /* Load from the nested guest into our buffer */ 506 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid, 507 eaddr, buf, NULL, n); 508 if (rc) 509 goto not_found; 510 511 /* Write what was loaded into our buffer back to the L1 guest */ 512 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); 513 rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n); 514 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); 515 if (rc) 516 goto not_found; 517 } else { 518 /* Load the data to be stored from the L1 guest into our buf */ 519 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); 520 rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n); 521 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); 522 if (rc) 523 goto not_found; 524 525 /* Store from our buffer into the nested guest */ 526 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid, 527 eaddr, NULL, buf, n); 528 if (rc) 529 goto not_found; 530 } 531 532 out_unlock: 533 mutex_unlock(&gp->tlb_lock); 534 kvmhv_put_nested(gp); 535 out_free: 536 kfree(buf); 537 return rc; 538 not_found: 539 rc = H_NOT_FOUND; 540 goto out_unlock; 541 } 542 543 /* 544 * Reload the partition table entry for a guest. 545 * Caller must hold gp->tlb_lock. 546 */ 547 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp) 548 { 549 int ret; 550 struct patb_entry ptbl_entry; 551 unsigned long ptbl_addr; 552 struct kvm *kvm = gp->l1_host; 553 554 ret = -EFAULT; 555 ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4); 556 if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 8))) { 557 int srcu_idx = srcu_read_lock(&kvm->srcu); 558 ret = kvm_read_guest(kvm, ptbl_addr, 559 &ptbl_entry, sizeof(ptbl_entry)); 560 srcu_read_unlock(&kvm->srcu, srcu_idx); 561 } 562 if (ret) { 563 gp->l1_gr_to_hr = 0; 564 gp->process_table = 0; 565 } else { 566 gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0); 567 gp->process_table = be64_to_cpu(ptbl_entry.patb1); 568 } 569 kvmhv_set_nested_ptbl(gp); 570 } 571 572 static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid) 573 { 574 struct kvm_nested_guest *gp; 575 long shadow_lpid; 576 577 gp = kzalloc(sizeof(*gp), GFP_KERNEL); 578 if (!gp) 579 return NULL; 580 gp->l1_host = kvm; 581 gp->l1_lpid = lpid; 582 mutex_init(&gp->tlb_lock); 583 gp->shadow_pgtable = pgd_alloc(kvm->mm); 584 if (!gp->shadow_pgtable) 585 goto out_free; 586 shadow_lpid = kvmppc_alloc_lpid(); 587 if (shadow_lpid < 0) 588 goto out_free2; 589 gp->shadow_lpid = shadow_lpid; 590 gp->radix = 1; 591 592 memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu)); 593 594 return gp; 595 596 out_free2: 597 pgd_free(kvm->mm, gp->shadow_pgtable); 598 out_free: 599 kfree(gp); 600 return NULL; 601 } 602 603 /* 604 * Free up any resources allocated for a nested guest. 605 */ 606 static void kvmhv_release_nested(struct kvm_nested_guest *gp) 607 { 608 struct kvm *kvm = gp->l1_host; 609 610 if (gp->shadow_pgtable) { 611 /* 612 * No vcpu is using this struct and no call to 613 * kvmhv_get_nested can find this struct, 614 * so we don't need to hold kvm->mmu_lock. 615 */ 616 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, 617 gp->shadow_lpid); 618 pgd_free(kvm->mm, gp->shadow_pgtable); 619 } 620 kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0); 621 kvmppc_free_lpid(gp->shadow_lpid); 622 kfree(gp); 623 } 624 625 static void kvmhv_remove_nested(struct kvm_nested_guest *gp) 626 { 627 struct kvm *kvm = gp->l1_host; 628 int lpid = gp->l1_lpid; 629 long ref; 630 631 spin_lock(&kvm->mmu_lock); 632 if (gp == kvm->arch.nested_guests[lpid]) { 633 kvm->arch.nested_guests[lpid] = NULL; 634 if (lpid == kvm->arch.max_nested_lpid) { 635 while (--lpid >= 0 && !kvm->arch.nested_guests[lpid]) 636 ; 637 kvm->arch.max_nested_lpid = lpid; 638 } 639 --gp->refcnt; 640 } 641 ref = gp->refcnt; 642 spin_unlock(&kvm->mmu_lock); 643 if (ref == 0) 644 kvmhv_release_nested(gp); 645 } 646 647 /* 648 * Free up all nested resources allocated for this guest. 649 * This is called with no vcpus of the guest running, when 650 * switching the guest to HPT mode or when destroying the 651 * guest. 652 */ 653 void kvmhv_release_all_nested(struct kvm *kvm) 654 { 655 int i; 656 struct kvm_nested_guest *gp; 657 struct kvm_nested_guest *freelist = NULL; 658 struct kvm_memory_slot *memslot; 659 int srcu_idx; 660 661 spin_lock(&kvm->mmu_lock); 662 for (i = 0; i <= kvm->arch.max_nested_lpid; i++) { 663 gp = kvm->arch.nested_guests[i]; 664 if (!gp) 665 continue; 666 kvm->arch.nested_guests[i] = NULL; 667 if (--gp->refcnt == 0) { 668 gp->next = freelist; 669 freelist = gp; 670 } 671 } 672 kvm->arch.max_nested_lpid = -1; 673 spin_unlock(&kvm->mmu_lock); 674 while ((gp = freelist) != NULL) { 675 freelist = gp->next; 676 kvmhv_release_nested(gp); 677 } 678 679 srcu_idx = srcu_read_lock(&kvm->srcu); 680 kvm_for_each_memslot(memslot, kvm_memslots(kvm)) 681 kvmhv_free_memslot_nest_rmap(memslot); 682 srcu_read_unlock(&kvm->srcu, srcu_idx); 683 } 684 685 /* caller must hold gp->tlb_lock */ 686 static void kvmhv_flush_nested(struct kvm_nested_guest *gp) 687 { 688 struct kvm *kvm = gp->l1_host; 689 690 spin_lock(&kvm->mmu_lock); 691 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid); 692 spin_unlock(&kvm->mmu_lock); 693 kvmhv_flush_lpid(gp->shadow_lpid); 694 kvmhv_update_ptbl_cache(gp); 695 if (gp->l1_gr_to_hr == 0) 696 kvmhv_remove_nested(gp); 697 } 698 699 struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid, 700 bool create) 701 { 702 struct kvm_nested_guest *gp, *newgp; 703 704 if (l1_lpid >= KVM_MAX_NESTED_GUESTS || 705 l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4))) 706 return NULL; 707 708 spin_lock(&kvm->mmu_lock); 709 gp = kvm->arch.nested_guests[l1_lpid]; 710 if (gp) 711 ++gp->refcnt; 712 spin_unlock(&kvm->mmu_lock); 713 714 if (gp || !create) 715 return gp; 716 717 newgp = kvmhv_alloc_nested(kvm, l1_lpid); 718 if (!newgp) 719 return NULL; 720 spin_lock(&kvm->mmu_lock); 721 if (kvm->arch.nested_guests[l1_lpid]) { 722 /* someone else beat us to it */ 723 gp = kvm->arch.nested_guests[l1_lpid]; 724 } else { 725 kvm->arch.nested_guests[l1_lpid] = newgp; 726 ++newgp->refcnt; 727 gp = newgp; 728 newgp = NULL; 729 if (l1_lpid > kvm->arch.max_nested_lpid) 730 kvm->arch.max_nested_lpid = l1_lpid; 731 } 732 ++gp->refcnt; 733 spin_unlock(&kvm->mmu_lock); 734 735 if (newgp) 736 kvmhv_release_nested(newgp); 737 738 return gp; 739 } 740 741 void kvmhv_put_nested(struct kvm_nested_guest *gp) 742 { 743 struct kvm *kvm = gp->l1_host; 744 long ref; 745 746 spin_lock(&kvm->mmu_lock); 747 ref = --gp->refcnt; 748 spin_unlock(&kvm->mmu_lock); 749 if (ref == 0) 750 kvmhv_release_nested(gp); 751 } 752 753 static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid) 754 { 755 if (lpid > kvm->arch.max_nested_lpid) 756 return NULL; 757 return kvm->arch.nested_guests[lpid]; 758 } 759 760 pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid, 761 unsigned long ea, unsigned *hshift) 762 { 763 struct kvm_nested_guest *gp; 764 pte_t *pte; 765 766 gp = kvmhv_find_nested(kvm, lpid); 767 if (!gp) 768 return NULL; 769 770 VM_WARN(!spin_is_locked(&kvm->mmu_lock), 771 "%s called with kvm mmu_lock not held \n", __func__); 772 pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift); 773 774 return pte; 775 } 776 777 static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2) 778 { 779 return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK | 780 RMAP_NESTED_GPA_MASK)); 781 } 782 783 void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp, 784 struct rmap_nested **n_rmap) 785 { 786 struct llist_node *entry = ((struct llist_head *) rmapp)->first; 787 struct rmap_nested *cursor; 788 u64 rmap, new_rmap = (*n_rmap)->rmap; 789 790 /* Are there any existing entries? */ 791 if (!(*rmapp)) { 792 /* No -> use the rmap as a single entry */ 793 *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY; 794 return; 795 } 796 797 /* Do any entries match what we're trying to insert? */ 798 for_each_nest_rmap_safe(cursor, entry, &rmap) { 799 if (kvmhv_n_rmap_is_equal(rmap, new_rmap)) 800 return; 801 } 802 803 /* Do we need to create a list or just add the new entry? */ 804 rmap = *rmapp; 805 if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */ 806 *rmapp = 0UL; 807 llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp); 808 if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */ 809 (*n_rmap)->list.next = (struct llist_node *) rmap; 810 811 /* Set NULL so not freed by caller */ 812 *n_rmap = NULL; 813 } 814 815 static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap, 816 unsigned long clr, unsigned long set, 817 unsigned long hpa, unsigned long mask) 818 { 819 unsigned long gpa; 820 unsigned int shift, lpid; 821 pte_t *ptep; 822 823 gpa = n_rmap & RMAP_NESTED_GPA_MASK; 824 lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT; 825 826 /* Find the pte */ 827 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); 828 /* 829 * If the pte is present and the pfn is still the same, update the pte. 830 * If the pfn has changed then this is a stale rmap entry, the nested 831 * gpa actually points somewhere else now, and there is nothing to do. 832 * XXX A future optimisation would be to remove the rmap entry here. 833 */ 834 if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) { 835 __radix_pte_update(ptep, clr, set); 836 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid); 837 } 838 } 839 840 /* 841 * For a given list of rmap entries, update the rc bits in all ptes in shadow 842 * page tables for nested guests which are referenced by the rmap list. 843 */ 844 void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp, 845 unsigned long clr, unsigned long set, 846 unsigned long hpa, unsigned long nbytes) 847 { 848 struct llist_node *entry = ((struct llist_head *) rmapp)->first; 849 struct rmap_nested *cursor; 850 unsigned long rmap, mask; 851 852 if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED)) 853 return; 854 855 mask = PTE_RPN_MASK & ~(nbytes - 1); 856 hpa &= mask; 857 858 for_each_nest_rmap_safe(cursor, entry, &rmap) 859 kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask); 860 } 861 862 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap, 863 unsigned long hpa, unsigned long mask) 864 { 865 struct kvm_nested_guest *gp; 866 unsigned long gpa; 867 unsigned int shift, lpid; 868 pte_t *ptep; 869 870 gpa = n_rmap & RMAP_NESTED_GPA_MASK; 871 lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT; 872 gp = kvmhv_find_nested(kvm, lpid); 873 if (!gp) 874 return; 875 876 /* Find and invalidate the pte */ 877 ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); 878 /* Don't spuriously invalidate ptes if the pfn has changed */ 879 if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) 880 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid); 881 } 882 883 static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp, 884 unsigned long hpa, unsigned long mask) 885 { 886 struct llist_node *entry = llist_del_all((struct llist_head *) rmapp); 887 struct rmap_nested *cursor; 888 unsigned long rmap; 889 890 for_each_nest_rmap_safe(cursor, entry, &rmap) { 891 kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask); 892 kfree(cursor); 893 } 894 } 895 896 /* called with kvm->mmu_lock held */ 897 void kvmhv_remove_nest_rmap_range(struct kvm *kvm, 898 const struct kvm_memory_slot *memslot, 899 unsigned long gpa, unsigned long hpa, 900 unsigned long nbytes) 901 { 902 unsigned long gfn, end_gfn; 903 unsigned long addr_mask; 904 905 if (!memslot) 906 return; 907 gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn; 908 end_gfn = gfn + (nbytes >> PAGE_SHIFT); 909 910 addr_mask = PTE_RPN_MASK & ~(nbytes - 1); 911 hpa &= addr_mask; 912 913 for (; gfn < end_gfn; gfn++) { 914 unsigned long *rmap = &memslot->arch.rmap[gfn]; 915 kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask); 916 } 917 } 918 919 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free) 920 { 921 unsigned long page; 922 923 for (page = 0; page < free->npages; page++) { 924 unsigned long rmap, *rmapp = &free->arch.rmap[page]; 925 struct rmap_nested *cursor; 926 struct llist_node *entry; 927 928 entry = llist_del_all((struct llist_head *) rmapp); 929 for_each_nest_rmap_safe(cursor, entry, &rmap) 930 kfree(cursor); 931 } 932 } 933 934 static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu, 935 struct kvm_nested_guest *gp, 936 long gpa, int *shift_ret) 937 { 938 struct kvm *kvm = vcpu->kvm; 939 bool ret = false; 940 pte_t *ptep; 941 int shift; 942 943 spin_lock(&kvm->mmu_lock); 944 ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift); 945 if (!shift) 946 shift = PAGE_SHIFT; 947 if (ptep && pte_present(*ptep)) { 948 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid); 949 ret = true; 950 } 951 spin_unlock(&kvm->mmu_lock); 952 953 if (shift_ret) 954 *shift_ret = shift; 955 return ret; 956 } 957 958 static inline int get_ric(unsigned int instr) 959 { 960 return (instr >> 18) & 0x3; 961 } 962 963 static inline int get_prs(unsigned int instr) 964 { 965 return (instr >> 17) & 0x1; 966 } 967 968 static inline int get_r(unsigned int instr) 969 { 970 return (instr >> 16) & 0x1; 971 } 972 973 static inline int get_lpid(unsigned long r_val) 974 { 975 return r_val & 0xffffffff; 976 } 977 978 static inline int get_is(unsigned long r_val) 979 { 980 return (r_val >> 10) & 0x3; 981 } 982 983 static inline int get_ap(unsigned long r_val) 984 { 985 return (r_val >> 5) & 0x7; 986 } 987 988 static inline long get_epn(unsigned long r_val) 989 { 990 return r_val >> 12; 991 } 992 993 static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid, 994 int ap, long epn) 995 { 996 struct kvm *kvm = vcpu->kvm; 997 struct kvm_nested_guest *gp; 998 long npages; 999 int shift, shadow_shift; 1000 unsigned long addr; 1001 1002 shift = ap_to_shift(ap); 1003 addr = epn << 12; 1004 if (shift < 0) 1005 /* Invalid ap encoding */ 1006 return -EINVAL; 1007 1008 addr &= ~((1UL << shift) - 1); 1009 npages = 1UL << (shift - PAGE_SHIFT); 1010 1011 gp = kvmhv_get_nested(kvm, lpid, false); 1012 if (!gp) /* No such guest -> nothing to do */ 1013 return 0; 1014 mutex_lock(&gp->tlb_lock); 1015 1016 /* There may be more than one host page backing this single guest pte */ 1017 do { 1018 kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift); 1019 1020 npages -= 1UL << (shadow_shift - PAGE_SHIFT); 1021 addr += 1UL << shadow_shift; 1022 } while (npages > 0); 1023 1024 mutex_unlock(&gp->tlb_lock); 1025 kvmhv_put_nested(gp); 1026 return 0; 1027 } 1028 1029 static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu, 1030 struct kvm_nested_guest *gp, int ric) 1031 { 1032 struct kvm *kvm = vcpu->kvm; 1033 1034 mutex_lock(&gp->tlb_lock); 1035 switch (ric) { 1036 case 0: 1037 /* Invalidate TLB */ 1038 spin_lock(&kvm->mmu_lock); 1039 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, 1040 gp->shadow_lpid); 1041 kvmhv_flush_lpid(gp->shadow_lpid); 1042 spin_unlock(&kvm->mmu_lock); 1043 break; 1044 case 1: 1045 /* 1046 * Invalidate PWC 1047 * We don't cache this -> nothing to do 1048 */ 1049 break; 1050 case 2: 1051 /* Invalidate TLB, PWC and caching of partition table entries */ 1052 kvmhv_flush_nested(gp); 1053 break; 1054 default: 1055 break; 1056 } 1057 mutex_unlock(&gp->tlb_lock); 1058 } 1059 1060 static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric) 1061 { 1062 struct kvm *kvm = vcpu->kvm; 1063 struct kvm_nested_guest *gp; 1064 int i; 1065 1066 spin_lock(&kvm->mmu_lock); 1067 for (i = 0; i <= kvm->arch.max_nested_lpid; i++) { 1068 gp = kvm->arch.nested_guests[i]; 1069 if (gp) { 1070 spin_unlock(&kvm->mmu_lock); 1071 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric); 1072 spin_lock(&kvm->mmu_lock); 1073 } 1074 } 1075 spin_unlock(&kvm->mmu_lock); 1076 } 1077 1078 static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr, 1079 unsigned long rsval, unsigned long rbval) 1080 { 1081 struct kvm *kvm = vcpu->kvm; 1082 struct kvm_nested_guest *gp; 1083 int r, ric, prs, is, ap; 1084 int lpid; 1085 long epn; 1086 int ret = 0; 1087 1088 ric = get_ric(instr); 1089 prs = get_prs(instr); 1090 r = get_r(instr); 1091 lpid = get_lpid(rsval); 1092 is = get_is(rbval); 1093 1094 /* 1095 * These cases are invalid and are not handled: 1096 * r != 1 -> Only radix supported 1097 * prs == 1 -> Not HV privileged 1098 * ric == 3 -> No cluster bombs for radix 1099 * is == 1 -> Partition scoped translations not associated with pid 1100 * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA 1101 */ 1102 if ((!r) || (prs) || (ric == 3) || (is == 1) || 1103 ((!is) && (ric == 1 || ric == 2))) 1104 return -EINVAL; 1105 1106 switch (is) { 1107 case 0: 1108 /* 1109 * We know ric == 0 1110 * Invalidate TLB for a given target address 1111 */ 1112 epn = get_epn(rbval); 1113 ap = get_ap(rbval); 1114 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn); 1115 break; 1116 case 2: 1117 /* Invalidate matching LPID */ 1118 gp = kvmhv_get_nested(kvm, lpid, false); 1119 if (gp) { 1120 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric); 1121 kvmhv_put_nested(gp); 1122 } 1123 break; 1124 case 3: 1125 /* Invalidate ALL LPIDs */ 1126 kvmhv_emulate_tlbie_all_lpid(vcpu, ric); 1127 break; 1128 default: 1129 ret = -EINVAL; 1130 break; 1131 } 1132 1133 return ret; 1134 } 1135 1136 /* 1137 * This handles the H_TLB_INVALIDATE hcall. 1138 * Parameters are (r4) tlbie instruction code, (r5) rS contents, 1139 * (r6) rB contents. 1140 */ 1141 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu) 1142 { 1143 int ret; 1144 1145 ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4), 1146 kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6)); 1147 if (ret) 1148 return H_PARAMETER; 1149 return H_SUCCESS; 1150 } 1151 1152 /* Used to convert a nested guest real address to a L1 guest real address */ 1153 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu, 1154 struct kvm_nested_guest *gp, 1155 unsigned long n_gpa, unsigned long dsisr, 1156 struct kvmppc_pte *gpte_p) 1157 { 1158 u64 fault_addr, flags = dsisr & DSISR_ISSTORE; 1159 int ret; 1160 1161 ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr, 1162 &fault_addr); 1163 1164 if (ret) { 1165 /* We didn't find a pte */ 1166 if (ret == -EINVAL) { 1167 /* Unsupported mmu config */ 1168 flags |= DSISR_UNSUPP_MMU; 1169 } else if (ret == -ENOENT) { 1170 /* No translation found */ 1171 flags |= DSISR_NOHPTE; 1172 } else if (ret == -EFAULT) { 1173 /* Couldn't access L1 real address */ 1174 flags |= DSISR_PRTABLE_FAULT; 1175 vcpu->arch.fault_gpa = fault_addr; 1176 } else { 1177 /* Unknown error */ 1178 return ret; 1179 } 1180 goto forward_to_l1; 1181 } else { 1182 /* We found a pte -> check permissions */ 1183 if (dsisr & DSISR_ISSTORE) { 1184 /* Can we write? */ 1185 if (!gpte_p->may_write) { 1186 flags |= DSISR_PROTFAULT; 1187 goto forward_to_l1; 1188 } 1189 } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) { 1190 /* Can we execute? */ 1191 if (!gpte_p->may_execute) { 1192 flags |= SRR1_ISI_N_G_OR_CIP; 1193 goto forward_to_l1; 1194 } 1195 } else { 1196 /* Can we read? */ 1197 if (!gpte_p->may_read && !gpte_p->may_write) { 1198 flags |= DSISR_PROTFAULT; 1199 goto forward_to_l1; 1200 } 1201 } 1202 } 1203 1204 return 0; 1205 1206 forward_to_l1: 1207 vcpu->arch.fault_dsisr = flags; 1208 if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) { 1209 vcpu->arch.shregs.msr &= SRR1_MSR_BITS; 1210 vcpu->arch.shregs.msr |= flags; 1211 } 1212 return RESUME_HOST; 1213 } 1214 1215 static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu, 1216 struct kvm_nested_guest *gp, 1217 unsigned long n_gpa, 1218 struct kvmppc_pte gpte, 1219 unsigned long dsisr) 1220 { 1221 struct kvm *kvm = vcpu->kvm; 1222 bool writing = !!(dsisr & DSISR_ISSTORE); 1223 u64 pgflags; 1224 long ret; 1225 1226 /* Are the rc bits set in the L1 partition scoped pte? */ 1227 pgflags = _PAGE_ACCESSED; 1228 if (writing) 1229 pgflags |= _PAGE_DIRTY; 1230 if (pgflags & ~gpte.rc) 1231 return RESUME_HOST; 1232 1233 spin_lock(&kvm->mmu_lock); 1234 /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */ 1235 ret = kvmppc_hv_handle_set_rc(kvm, false, writing, 1236 gpte.raddr, kvm->arch.lpid); 1237 if (!ret) { 1238 ret = -EINVAL; 1239 goto out_unlock; 1240 } 1241 1242 /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */ 1243 ret = kvmppc_hv_handle_set_rc(kvm, true, writing, 1244 n_gpa, gp->l1_lpid); 1245 if (!ret) 1246 ret = -EINVAL; 1247 else 1248 ret = 0; 1249 1250 out_unlock: 1251 spin_unlock(&kvm->mmu_lock); 1252 return ret; 1253 } 1254 1255 static inline int kvmppc_radix_level_to_shift(int level) 1256 { 1257 switch (level) { 1258 case 2: 1259 return PUD_SHIFT; 1260 case 1: 1261 return PMD_SHIFT; 1262 default: 1263 return PAGE_SHIFT; 1264 } 1265 } 1266 1267 static inline int kvmppc_radix_shift_to_level(int shift) 1268 { 1269 if (shift == PUD_SHIFT) 1270 return 2; 1271 if (shift == PMD_SHIFT) 1272 return 1; 1273 if (shift == PAGE_SHIFT) 1274 return 0; 1275 WARN_ON_ONCE(1); 1276 return 0; 1277 } 1278 1279 /* called with gp->tlb_lock held */ 1280 static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu, 1281 struct kvm_nested_guest *gp) 1282 { 1283 struct kvm *kvm = vcpu->kvm; 1284 struct kvm_memory_slot *memslot; 1285 struct rmap_nested *n_rmap; 1286 struct kvmppc_pte gpte; 1287 pte_t pte, *pte_p; 1288 unsigned long mmu_seq; 1289 unsigned long dsisr = vcpu->arch.fault_dsisr; 1290 unsigned long ea = vcpu->arch.fault_dar; 1291 unsigned long *rmapp; 1292 unsigned long n_gpa, gpa, gfn, perm = 0UL; 1293 unsigned int shift, l1_shift, level; 1294 bool writing = !!(dsisr & DSISR_ISSTORE); 1295 bool kvm_ro = false; 1296 long int ret; 1297 1298 if (!gp->l1_gr_to_hr) { 1299 kvmhv_update_ptbl_cache(gp); 1300 if (!gp->l1_gr_to_hr) 1301 return RESUME_HOST; 1302 } 1303 1304 /* Convert the nested guest real address into a L1 guest real address */ 1305 1306 n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL; 1307 if (!(dsisr & DSISR_PRTABLE_FAULT)) 1308 n_gpa |= ea & 0xFFF; 1309 ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte); 1310 1311 /* 1312 * If the hardware found a translation but we don't now have a usable 1313 * translation in the l1 partition-scoped tree, remove the shadow pte 1314 * and let the guest retry. 1315 */ 1316 if (ret == RESUME_HOST && 1317 (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G | 1318 DSISR_BAD_COPYPASTE))) 1319 goto inval; 1320 if (ret) 1321 return ret; 1322 1323 /* Failed to set the reference/change bits */ 1324 if (dsisr & DSISR_SET_RC) { 1325 ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr); 1326 if (ret == RESUME_HOST) 1327 return ret; 1328 if (ret) 1329 goto inval; 1330 dsisr &= ~DSISR_SET_RC; 1331 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE | 1332 DSISR_PROTFAULT))) 1333 return RESUME_GUEST; 1334 } 1335 1336 /* 1337 * We took an HISI or HDSI while we were running a nested guest which 1338 * means we have no partition scoped translation for that. This means 1339 * we need to insert a pte for the mapping into our shadow_pgtable. 1340 */ 1341 1342 l1_shift = gpte.page_shift; 1343 if (l1_shift < PAGE_SHIFT) { 1344 /* We don't support l1 using a page size smaller than our own */ 1345 pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n", 1346 l1_shift, PAGE_SHIFT); 1347 return -EINVAL; 1348 } 1349 gpa = gpte.raddr; 1350 gfn = gpa >> PAGE_SHIFT; 1351 1352 /* 1. Get the corresponding host memslot */ 1353 1354 memslot = gfn_to_memslot(kvm, gfn); 1355 if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) { 1356 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) { 1357 /* unusual error -> reflect to the guest as a DSI */ 1358 kvmppc_core_queue_data_storage(vcpu, ea, dsisr); 1359 return RESUME_GUEST; 1360 } 1361 1362 /* passthrough of emulated MMIO case */ 1363 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing); 1364 } 1365 if (memslot->flags & KVM_MEM_READONLY) { 1366 if (writing) { 1367 /* Give the guest a DSI */ 1368 kvmppc_core_queue_data_storage(vcpu, ea, 1369 DSISR_ISSTORE | DSISR_PROTFAULT); 1370 return RESUME_GUEST; 1371 } 1372 kvm_ro = true; 1373 } 1374 1375 /* 2. Find the host pte for this L1 guest real address */ 1376 1377 /* Used to check for invalidations in progress */ 1378 mmu_seq = kvm->mmu_notifier_seq; 1379 smp_rmb(); 1380 1381 /* See if can find translation in our partition scoped tables for L1 */ 1382 pte = __pte(0); 1383 spin_lock(&kvm->mmu_lock); 1384 pte_p = find_kvm_secondary_pte(kvm, gpa, &shift); 1385 if (!shift) 1386 shift = PAGE_SHIFT; 1387 if (pte_p) 1388 pte = *pte_p; 1389 spin_unlock(&kvm->mmu_lock); 1390 1391 if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) { 1392 /* No suitable pte found -> try to insert a mapping */ 1393 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, 1394 writing, kvm_ro, &pte, &level); 1395 if (ret == -EAGAIN) 1396 return RESUME_GUEST; 1397 else if (ret) 1398 return ret; 1399 shift = kvmppc_radix_level_to_shift(level); 1400 } 1401 /* Align gfn to the start of the page */ 1402 gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT; 1403 1404 /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */ 1405 1406 /* The permissions is the combination of the host and l1 guest ptes */ 1407 perm |= gpte.may_read ? 0UL : _PAGE_READ; 1408 perm |= gpte.may_write ? 0UL : _PAGE_WRITE; 1409 perm |= gpte.may_execute ? 0UL : _PAGE_EXEC; 1410 /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */ 1411 perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED; 1412 perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY; 1413 pte = __pte(pte_val(pte) & ~perm); 1414 1415 /* What size pte can we insert? */ 1416 if (shift > l1_shift) { 1417 u64 mask; 1418 unsigned int actual_shift = PAGE_SHIFT; 1419 if (PMD_SHIFT < l1_shift) 1420 actual_shift = PMD_SHIFT; 1421 mask = (1UL << shift) - (1UL << actual_shift); 1422 pte = __pte(pte_val(pte) | (gpa & mask)); 1423 shift = actual_shift; 1424 } 1425 level = kvmppc_radix_shift_to_level(shift); 1426 n_gpa &= ~((1UL << shift) - 1); 1427 1428 /* 4. Insert the pte into our shadow_pgtable */ 1429 1430 n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL); 1431 if (!n_rmap) 1432 return RESUME_GUEST; /* Let the guest try again */ 1433 n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) | 1434 (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT); 1435 rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; 1436 ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level, 1437 mmu_seq, gp->shadow_lpid, rmapp, &n_rmap); 1438 kfree(n_rmap); 1439 if (ret == -EAGAIN) 1440 ret = RESUME_GUEST; /* Let the guest try again */ 1441 1442 return ret; 1443 1444 inval: 1445 kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL); 1446 return RESUME_GUEST; 1447 } 1448 1449 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu) 1450 { 1451 struct kvm_nested_guest *gp = vcpu->arch.nested; 1452 long int ret; 1453 1454 mutex_lock(&gp->tlb_lock); 1455 ret = __kvmhv_nested_page_fault(vcpu, gp); 1456 mutex_unlock(&gp->tlb_lock); 1457 return ret; 1458 } 1459 1460 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid) 1461 { 1462 int ret = -1; 1463 1464 spin_lock(&kvm->mmu_lock); 1465 while (++lpid <= kvm->arch.max_nested_lpid) { 1466 if (kvm->arch.nested_guests[lpid]) { 1467 ret = lpid; 1468 break; 1469 } 1470 } 1471 spin_unlock(&kvm->mmu_lock); 1472 return ret; 1473 } 1474