arch/powerpc/kvm/book3s_hv_nested.c

   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 #include <asm/plpar_wrappers.h>
  23
  24 static struct patb_entry *pseries_partition_tb;
  25
  26 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp);
  27 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free);
  28
  29 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
  30 {
  31         struct kvmppc_vcore *vc = vcpu->arch.vcore;
  32
  33         hr->pcr = vc->pcr | PCR_MASK;
  34         hr->dpdes = vc->dpdes;
  35         hr->hfscr = vcpu->arch.hfscr;
  36         hr->tb_offset = vc->tb_offset;
  37         hr->dawr0 = vcpu->arch.dawr0;
  38         hr->dawrx0 = vcpu->arch.dawrx0;
  39         hr->ciabr = vcpu->arch.ciabr;
  40         hr->purr = vcpu->arch.purr;
  41         hr->spurr = vcpu->arch.spurr;
  42         hr->ic = vcpu->arch.ic;
  43         hr->vtb = vc->vtb;
  44         hr->srr0 = vcpu->arch.shregs.srr0;
  45         hr->srr1 = vcpu->arch.shregs.srr1;
  46         hr->sprg[0] = vcpu->arch.shregs.sprg0;
  47         hr->sprg[1] = vcpu->arch.shregs.sprg1;
  48         hr->sprg[2] = vcpu->arch.shregs.sprg2;
  49         hr->sprg[3] = vcpu->arch.shregs.sprg3;
  50         hr->pidr = vcpu->arch.pid;
  51         hr->cfar = vcpu->arch.cfar;
  52         hr->ppr = vcpu->arch.ppr;
  53         hr->dawr1 = vcpu->arch.dawr1;
  54         hr->dawrx1 = vcpu->arch.dawrx1;
  55 }
  56
  57 /* Use noinline_for_stack due to https://bugs.llvm.org/show_bug.cgi?id=49610 */
  58 static noinline_for_stack void byteswap_pt_regs(struct pt_regs *regs)
  59 {
  60         unsigned long *addr = (unsigned long *) regs;
  61
  62         for (; addr < ((unsigned long *) (regs + 1)); addr++)
  63                 *addr = swab64(*addr);
  64 }
  65
  66 static void byteswap_hv_regs(struct hv_guest_state *hr)
  67 {
  68         hr->version = swab64(hr->version);
  69         hr->lpid = swab32(hr->lpid);
  70         hr->vcpu_token = swab32(hr->vcpu_token);
  71         hr->lpcr = swab64(hr->lpcr);
  72         hr->pcr = swab64(hr->pcr) | PCR_MASK;
  73         hr->amor = swab64(hr->amor);
  74         hr->dpdes = swab64(hr->dpdes);
  75         hr->hfscr = swab64(hr->hfscr);
  76         hr->tb_offset = swab64(hr->tb_offset);
  77         hr->dawr0 = swab64(hr->dawr0);
  78         hr->dawrx0 = swab64(hr->dawrx0);
  79         hr->ciabr = swab64(hr->ciabr);
  80         hr->hdec_expiry = swab64(hr->hdec_expiry);
  81         hr->purr = swab64(hr->purr);
  82         hr->spurr = swab64(hr->spurr);
  83         hr->ic = swab64(hr->ic);
  84         hr->vtb = swab64(hr->vtb);
  85         hr->hdar = swab64(hr->hdar);
  86         hr->hdsisr = swab64(hr->hdsisr);
  87         hr->heir = swab64(hr->heir);
  88         hr->asdr = swab64(hr->asdr);
  89         hr->srr0 = swab64(hr->srr0);
  90         hr->srr1 = swab64(hr->srr1);
  91         hr->sprg[0] = swab64(hr->sprg[0]);
  92         hr->sprg[1] = swab64(hr->sprg[1]);
  93         hr->sprg[2] = swab64(hr->sprg[2]);
  94         hr->sprg[3] = swab64(hr->sprg[3]);
  95         hr->pidr = swab64(hr->pidr);
  96         hr->cfar = swab64(hr->cfar);
  97         hr->ppr = swab64(hr->ppr);
  98         hr->dawr1 = swab64(hr->dawr1);
  99         hr->dawrx1 = swab64(hr->dawrx1);
 100 }
 101
 102 static void save_hv_return_state(struct kvm_vcpu *vcpu,
 103                                  struct hv_guest_state *hr)
 104 {
 105         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 106
 107         hr->dpdes = vc->dpdes;
 108         hr->purr = vcpu->arch.purr;
 109         hr->spurr = vcpu->arch.spurr;
 110         hr->ic = vcpu->arch.ic;
 111         hr->vtb = vc->vtb;
 112         hr->srr0 = vcpu->arch.shregs.srr0;
 113         hr->srr1 = vcpu->arch.shregs.srr1;
 114         hr->sprg[0] = vcpu->arch.shregs.sprg0;
 115         hr->sprg[1] = vcpu->arch.shregs.sprg1;
 116         hr->sprg[2] = vcpu->arch.shregs.sprg2;
 117         hr->sprg[3] = vcpu->arch.shregs.sprg3;
 118         hr->pidr = vcpu->arch.pid;
 119         hr->cfar = vcpu->arch.cfar;
 120         hr->ppr = vcpu->arch.ppr;
 121         switch (vcpu->arch.trap) {
 122         case BOOK3S_INTERRUPT_H_DATA_STORAGE:
 123                 hr->hdar = vcpu->arch.fault_dar;
 124                 hr->hdsisr = vcpu->arch.fault_dsisr;
 125                 hr->asdr = vcpu->arch.fault_gpa;
 126                 break;
 127         case BOOK3S_INTERRUPT_H_INST_STORAGE:
 128                 hr->asdr = vcpu->arch.fault_gpa;
 129                 break;
 130         case BOOK3S_INTERRUPT_H_FAC_UNAVAIL:
 131                 hr->hfscr = ((~HFSCR_INTR_CAUSE & hr->hfscr) |
 132                              (HFSCR_INTR_CAUSE & vcpu->arch.hfscr));
 133                 break;
 134         case BOOK3S_INTERRUPT_H_EMUL_ASSIST:
 135                 hr->heir = vcpu->arch.emul_inst;
 136                 break;
 137         }
 138 }
 139
 140 static void restore_hv_regs(struct kvm_vcpu *vcpu, const struct hv_guest_state *hr)
 141 {
 142         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 143
 144         vc->pcr = hr->pcr | PCR_MASK;
 145         vc->dpdes = hr->dpdes;
 146         vcpu->arch.hfscr = hr->hfscr;
 147         vcpu->arch.dawr0 = hr->dawr0;
 148         vcpu->arch.dawrx0 = hr->dawrx0;
 149         vcpu->arch.ciabr = hr->ciabr;
 150         vcpu->arch.purr = hr->purr;
 151         vcpu->arch.spurr = hr->spurr;
 152         vcpu->arch.ic = hr->ic;
 153         vc->vtb = hr->vtb;
 154         vcpu->arch.shregs.srr0 = hr->srr0;
 155         vcpu->arch.shregs.srr1 = hr->srr1;
 156         vcpu->arch.shregs.sprg0 = hr->sprg[0];
 157         vcpu->arch.shregs.sprg1 = hr->sprg[1];
 158         vcpu->arch.shregs.sprg2 = hr->sprg[2];
 159         vcpu->arch.shregs.sprg3 = hr->sprg[3];
 160         vcpu->arch.pid = hr->pidr;
 161         vcpu->arch.cfar = hr->cfar;
 162         vcpu->arch.ppr = hr->ppr;
 163         vcpu->arch.dawr1 = hr->dawr1;
 164         vcpu->arch.dawrx1 = hr->dawrx1;
 165 }
 166
 167 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
 168                                    struct hv_guest_state *hr)
 169 {
 170         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 171
 172         vc->dpdes = hr->dpdes;
 173         vcpu->arch.hfscr = hr->hfscr;
 174         vcpu->arch.purr = hr->purr;
 175         vcpu->arch.spurr = hr->spurr;
 176         vcpu->arch.ic = hr->ic;
 177         vc->vtb = hr->vtb;
 178         vcpu->arch.fault_dar = hr->hdar;
 179         vcpu->arch.fault_dsisr = hr->hdsisr;
 180         vcpu->arch.fault_gpa = hr->asdr;
 181         vcpu->arch.emul_inst = hr->heir;
 182         vcpu->arch.shregs.srr0 = hr->srr0;
 183         vcpu->arch.shregs.srr1 = hr->srr1;
 184         vcpu->arch.shregs.sprg0 = hr->sprg[0];
 185         vcpu->arch.shregs.sprg1 = hr->sprg[1];
 186         vcpu->arch.shregs.sprg2 = hr->sprg[2];
 187         vcpu->arch.shregs.sprg3 = hr->sprg[3];
 188         vcpu->arch.pid = hr->pidr;
 189         vcpu->arch.cfar = hr->cfar;
 190         vcpu->arch.ppr = hr->ppr;
 191 }
 192
 193 static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr)
 194 {
 195         /* No need to reflect the page fault to L1, we've handled it */
 196         vcpu->arch.trap = 0;
 197
 198         /*
 199          * Since the L2 gprs have already been written back into L1 memory when
 200          * we complete the mmio, store the L1 memory location of the L2 gpr
 201          * being loaded into by the mmio so that the loaded value can be
 202          * written there in kvmppc_complete_mmio_load()
 203          */
 204         if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR)
 205             && (vcpu->mmio_is_write == 0)) {
 206                 vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr +
 207                                            offsetof(struct pt_regs,
 208                                                     gpr[vcpu->arch.io_gpr]);
 209                 vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR;
 210         }
 211 }
 212
 213 static int kvmhv_read_guest_state_and_regs(struct kvm_vcpu *vcpu,
 214                                            struct hv_guest_state *l2_hv,
 215                                            struct pt_regs *l2_regs,
 216                                            u64 hv_ptr, u64 regs_ptr)
 217 {
 218         int size;
 219
 220         if (kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv->version,
 221                                 sizeof(l2_hv->version)))
 222                 return -1;
 223
 224         if (kvmppc_need_byteswap(vcpu))
 225                 l2_hv->version = swab64(l2_hv->version);
 226
 227         size = hv_guest_state_size(l2_hv->version);
 228         if (size < 0)
 229                 return -1;
 230
 231         return kvm_vcpu_read_guest(vcpu, hv_ptr, l2_hv, size) ||
 232                 kvm_vcpu_read_guest(vcpu, regs_ptr, l2_regs,
 233                                     sizeof(struct pt_regs));
 234 }
 235
 236 static int kvmhv_write_guest_state_and_regs(struct kvm_vcpu *vcpu,
 237                                             struct hv_guest_state *l2_hv,
 238                                             struct pt_regs *l2_regs,
 239                                             u64 hv_ptr, u64 regs_ptr)
 240 {
 241         int size;
 242
 243         size = hv_guest_state_size(l2_hv->version);
 244         if (size < 0)
 245                 return -1;
 246
 247         return kvm_vcpu_write_guest(vcpu, hv_ptr, l2_hv, size) ||
 248                 kvm_vcpu_write_guest(vcpu, regs_ptr, l2_regs,
 249                                      sizeof(struct pt_regs));
 250 }
 251
 252 static void load_l2_hv_regs(struct kvm_vcpu *vcpu,
 253                             const struct hv_guest_state *l2_hv,
 254                             const struct hv_guest_state *l1_hv, u64 *lpcr)
 255 {
 256         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 257         u64 mask;
 258
 259         restore_hv_regs(vcpu, l2_hv);
 260
 261         /*
 262          * Don't let L1 change LPCR bits for the L2 except these:
 263          */
 264         mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD |
 265                 LPCR_LPES | LPCR_MER;
 266
 267         /*
 268          * Additional filtering is required depending on hardware
 269          * and configuration.
 270          */
 271         *lpcr = kvmppc_filter_lpcr_hv(vcpu->kvm,
 272                                       (vc->lpcr & ~mask) | (*lpcr & mask));
 273
 274         /*
 275          * Don't let L1 enable features for L2 which we don't allow for L1,
 276          * but preserve the interrupt cause field.
 277          */
 278         vcpu->arch.hfscr = l2_hv->hfscr & (HFSCR_INTR_CAUSE | vcpu->arch.hfscr_permitted);
 279
 280         /* Don't let data address watchpoint match in hypervisor state */
 281         vcpu->arch.dawrx0 = l2_hv->dawrx0 & ~DAWRX_HYP;
 282         vcpu->arch.dawrx1 = l2_hv->dawrx1 & ~DAWRX_HYP;
 283
 284         /* Don't let completed instruction address breakpt match in HV state */
 285         if ((l2_hv->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER)
 286                 vcpu->arch.ciabr = l2_hv->ciabr & ~CIABR_PRIV;
 287 }
 288
 289 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
 290 {
 291         long int err, r;
 292         struct kvm_nested_guest *l2;
 293         struct pt_regs l2_regs, saved_l1_regs;
 294         struct hv_guest_state l2_hv = {0}, saved_l1_hv;
 295         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 296         u64 hv_ptr, regs_ptr;
 297         u64 hdec_exp, lpcr;
 298         s64 delta_purr, delta_spurr, delta_ic, delta_vtb;
 299
 300         if (vcpu->kvm->arch.l1_ptcr == 0)
 301                 return H_NOT_AVAILABLE;
 302
 303         if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr))
 304                 return H_BAD_MODE;
 305
 306         /* copy parameters in */
 307         hv_ptr = kvmppc_get_gpr(vcpu, 4);
 308         regs_ptr = kvmppc_get_gpr(vcpu, 5);
 309         kvm_vcpu_srcu_read_lock(vcpu);
 310         err = kvmhv_read_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 311                                               hv_ptr, regs_ptr);
 312         kvm_vcpu_srcu_read_unlock(vcpu);
 313         if (err)
 314                 return H_PARAMETER;
 315
 316         if (kvmppc_need_byteswap(vcpu))
 317                 byteswap_hv_regs(&l2_hv);
 318         if (l2_hv.version > HV_GUEST_STATE_VERSION)
 319                 return H_P2;
 320
 321         if (kvmppc_need_byteswap(vcpu))
 322                 byteswap_pt_regs(&l2_regs);
 323         if (l2_hv.vcpu_token >= NR_CPUS)
 324                 return H_PARAMETER;
 325
 326         /*
 327          * L1 must have set up a suspended state to enter the L2 in a
 328          * transactional state, and only in that case. These have to be
 329          * filtered out here to prevent causing a TM Bad Thing in the
 330          * host HRFID. We could synthesize a TM Bad Thing back to the L1
 331          * here but there doesn't seem like much point.
 332          */
 333         if (MSR_TM_SUSPENDED(vcpu->arch.shregs.msr)) {
 334                 if (!MSR_TM_ACTIVE(l2_regs.msr))
 335                         return H_BAD_MODE;
 336         } else {
 337                 if (l2_regs.msr & MSR_TS_MASK)
 338                         return H_BAD_MODE;
 339                 if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_TS_MASK))
 340                         return H_BAD_MODE;
 341         }
 342
 343         /* translate lpid */
 344         l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true);
 345         if (!l2)
 346                 return H_PARAMETER;
 347         if (!l2->l1_gr_to_hr) {
 348                 mutex_lock(&l2->tlb_lock);
 349                 kvmhv_update_ptbl_cache(l2);
 350                 mutex_unlock(&l2->tlb_lock);
 351         }
 352
 353         /* save l1 values of things */
 354         vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
 355         saved_l1_regs = vcpu->arch.regs;
 356         kvmhv_save_hv_regs(vcpu, &saved_l1_hv);
 357
 358         /* convert TB values/offsets to host (L0) values */
 359         hdec_exp = l2_hv.hdec_expiry - vc->tb_offset;
 360         vc->tb_offset += l2_hv.tb_offset;
 361         vcpu->arch.dec_expires += l2_hv.tb_offset;
 362
 363         /* set L1 state to L2 state */
 364         vcpu->arch.nested = l2;
 365         vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token;
 366         vcpu->arch.nested_hfscr = l2_hv.hfscr;
 367         vcpu->arch.regs = l2_regs;
 368
 369         /* Guest must always run with ME enabled, HV disabled. */
 370         vcpu->arch.shregs.msr = (vcpu->arch.regs.msr | MSR_ME) & ~MSR_HV;
 371
 372         lpcr = l2_hv.lpcr;
 373         load_l2_hv_regs(vcpu, &l2_hv, &saved_l1_hv, &lpcr);
 374
 375         vcpu->arch.ret = RESUME_GUEST;
 376         vcpu->arch.trap = 0;
 377         do {
 378                 r = kvmhv_run_single_vcpu(vcpu, hdec_exp, lpcr);
 379         } while (is_kvmppc_resume_guest(r));
 380
 381         /* save L2 state for return */
 382         l2_regs = vcpu->arch.regs;
 383         l2_regs.msr = vcpu->arch.shregs.msr;
 384         delta_purr = vcpu->arch.purr - l2_hv.purr;
 385         delta_spurr = vcpu->arch.spurr - l2_hv.spurr;
 386         delta_ic = vcpu->arch.ic - l2_hv.ic;
 387         delta_vtb = vc->vtb - l2_hv.vtb;
 388         save_hv_return_state(vcpu, &l2_hv);
 389
 390         /* restore L1 state */
 391         vcpu->arch.nested = NULL;
 392         vcpu->arch.regs = saved_l1_regs;
 393         vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK;
 394         /* set L1 MSR TS field according to L2 transaction state */
 395         if (l2_regs.msr & MSR_TS_MASK)
 396                 vcpu->arch.shregs.msr |= MSR_TS_S;
 397         vc->tb_offset = saved_l1_hv.tb_offset;
 398         /* XXX: is this always the same delta as saved_l1_hv.tb_offset? */
 399         vcpu->arch.dec_expires -= l2_hv.tb_offset;
 400         restore_hv_regs(vcpu, &saved_l1_hv);
 401         vcpu->arch.purr += delta_purr;
 402         vcpu->arch.spurr += delta_spurr;
 403         vcpu->arch.ic += delta_ic;
 404         vc->vtb += delta_vtb;
 405
 406         kvmhv_put_nested(l2);
 407
 408         /* copy l2_hv_state and regs back to guest */
 409         if (kvmppc_need_byteswap(vcpu)) {
 410                 byteswap_hv_regs(&l2_hv);
 411                 byteswap_pt_regs(&l2_regs);
 412         }
 413         kvm_vcpu_srcu_read_lock(vcpu);
 414         err = kvmhv_write_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 415                                                hv_ptr, regs_ptr);
 416         kvm_vcpu_srcu_read_unlock(vcpu);
 417         if (err)
 418                 return H_AUTHORITY;
 419
 420         if (r == -EINTR)
 421                 return H_INTERRUPT;
 422
 423         if (vcpu->mmio_needed) {
 424                 kvmhv_nested_mmio_needed(vcpu, regs_ptr);
 425                 return H_TOO_HARD;
 426         }
 427
 428         return vcpu->arch.trap;
 429 }
 430
 431 long kvmhv_nested_init(void)
 432 {
 433         long int ptb_order;
 434         unsigned long ptcr;
 435         long rc;
 436
 437         if (!kvmhv_on_pseries())
 438                 return 0;
 439         if (!radix_enabled())
 440                 return -ENODEV;
 441
 442         /* find log base 2 of KVMPPC_NR_LPIDS, rounding up */
 443         ptb_order = __ilog2(KVMPPC_NR_LPIDS - 1) + 1;
 444         if (ptb_order < 8)
 445                 ptb_order = 8;
 446         pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order,
 447                                        GFP_KERNEL);
 448         if (!pseries_partition_tb) {
 449                 pr_err("kvm-hv: failed to allocated nested partition table\n");
 450                 return -ENOMEM;
 451         }
 452
 453         ptcr = __pa(pseries_partition_tb) | (ptb_order - 8);
 454         rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr);
 455         if (rc != H_SUCCESS) {
 456                 pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n",
 457                        rc);
 458                 kfree(pseries_partition_tb);
 459                 pseries_partition_tb = NULL;
 460                 return -ENODEV;
 461         }
 462
 463         return 0;
 464 }
 465
 466 void kvmhv_nested_exit(void)
 467 {
 468         /*
 469          * N.B. the kvmhv_on_pseries() test is there because it enables
 470          * the compiler to remove the call to plpar_hcall_norets()
 471          * when CONFIG_PPC_PSERIES=n.
 472          */
 473         if (kvmhv_on_pseries() && pseries_partition_tb) {
 474                 plpar_hcall_norets(H_SET_PARTITION_TABLE, 0);
 475                 kfree(pseries_partition_tb);
 476                 pseries_partition_tb = NULL;
 477         }
 478 }
 479
 480 static void kvmhv_flush_lpid(unsigned int lpid)
 481 {
 482         long rc;
 483
 484         if (!kvmhv_on_pseries()) {
 485                 radix__flush_all_lpid(lpid);
 486                 return;
 487         }
 488
 489         if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE))
 490                 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
 491                                         lpid, TLBIEL_INVAL_SET_LPID);
 492         else
 493                 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
 494                                             H_RPTI_TYPE_NESTED |
 495                                             H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
 496                                             H_RPTI_TYPE_PAT,
 497                                             H_RPTI_PAGE_ALL, 0, -1UL);
 498         if (rc)
 499                 pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
 500 }
 501
 502 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1)
 503 {
 504         if (!kvmhv_on_pseries()) {
 505                 mmu_partition_table_set_entry(lpid, dw0, dw1, true);
 506                 return;
 507         }
 508
 509         pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
 510         pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
 511         /* L0 will do the necessary barriers */
 512         kvmhv_flush_lpid(lpid);
 513 }
 514
 515 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp)
 516 {
 517         unsigned long dw0;
 518
 519         dw0 = PATB_HR | radix__get_tree_size() |
 520                 __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE;
 521         kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table);
 522 }
 523
 524 void kvmhv_vm_nested_init(struct kvm *kvm)
 525 {
 526         kvm->arch.max_nested_lpid = -1;
 527 }
 528
 529 /*
 530  * Handle the H_SET_PARTITION_TABLE hcall.
 531  * r4 = guest real address of partition table + log_2(size) - 12
 532  * (formatted as for the PTCR).
 533  */
 534 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu)
 535 {
 536         struct kvm *kvm = vcpu->kvm;
 537         unsigned long ptcr = kvmppc_get_gpr(vcpu, 4);
 538         int srcu_idx;
 539         long ret = H_SUCCESS;
 540
 541         srcu_idx = srcu_read_lock(&kvm->srcu);
 542         /*
 543          * Limit the partition table to 4096 entries (because that's what
 544          * hardware supports), and check the base address.
 545          */
 546         if ((ptcr & PRTS_MASK) > 12 - 8 ||
 547             !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT))
 548                 ret = H_PARAMETER;
 549         srcu_read_unlock(&kvm->srcu, srcu_idx);
 550         if (ret == H_SUCCESS)
 551                 kvm->arch.l1_ptcr = ptcr;
 552         return ret;
 553 }
 554
 555 /*
 556  * Handle the H_COPY_TOFROM_GUEST hcall.
 557  * r4 = L1 lpid of nested guest
 558  * r5 = pid
 559  * r6 = eaddr to access
 560  * r7 = to buffer (L1 gpa)
 561  * r8 = from buffer (L1 gpa)
 562  * r9 = n bytes to copy
 563  */
 564 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu)
 565 {
 566         struct kvm_nested_guest *gp;
 567         int l1_lpid = kvmppc_get_gpr(vcpu, 4);
 568         int pid = kvmppc_get_gpr(vcpu, 5);
 569         gva_t eaddr = kvmppc_get_gpr(vcpu, 6);
 570         gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7);
 571         gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8);
 572         void *buf;
 573         unsigned long n = kvmppc_get_gpr(vcpu, 9);
 574         bool is_load = !!gp_to;
 575         long rc;
 576
 577         if (gp_to && gp_from) /* One must be NULL to determine the direction */
 578                 return H_PARAMETER;
 579
 580         if (eaddr & (0xFFFUL << 52))
 581                 return H_PARAMETER;
 582
 583         buf = kzalloc(n, GFP_KERNEL | __GFP_NOWARN);
 584         if (!buf)
 585                 return H_NO_MEM;
 586
 587         gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false);
 588         if (!gp) {
 589                 rc = H_PARAMETER;
 590                 goto out_free;
 591         }
 592
 593         mutex_lock(&gp->tlb_lock);
 594
 595         if (is_load) {
 596                 /* Load from the nested guest into our buffer */
 597                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 598                                                      eaddr, buf, NULL, n);
 599                 if (rc)
 600                         goto not_found;
 601
 602                 /* Write what was loaded into our buffer back to the L1 guest */
 603                 kvm_vcpu_srcu_read_lock(vcpu);
 604                 rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n);
 605                 kvm_vcpu_srcu_read_unlock(vcpu);
 606                 if (rc)
 607                         goto not_found;
 608         } else {
 609                 /* Load the data to be stored from the L1 guest into our buf */
 610                 kvm_vcpu_srcu_read_lock(vcpu);
 611                 rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n);
 612                 kvm_vcpu_srcu_read_unlock(vcpu);
 613                 if (rc)
 614                         goto not_found;
 615
 616                 /* Store from our buffer into the nested guest */
 617                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 618                                                      eaddr, NULL, buf, n);
 619                 if (rc)
 620                         goto not_found;
 621         }
 622
 623 out_unlock:
 624         mutex_unlock(&gp->tlb_lock);
 625         kvmhv_put_nested(gp);
 626 out_free:
 627         kfree(buf);
 628         return rc;
 629 not_found:
 630         rc = H_NOT_FOUND;
 631         goto out_unlock;
 632 }
 633
 634 /*
 635  * Reload the partition table entry for a guest.
 636  * Caller must hold gp->tlb_lock.
 637  */
 638 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp)
 639 {
 640         int ret;
 641         struct patb_entry ptbl_entry;
 642         unsigned long ptbl_addr;
 643         struct kvm *kvm = gp->l1_host;
 644
 645         ret = -EFAULT;
 646         ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4);
 647         if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 8))) {
 648                 int srcu_idx = srcu_read_lock(&kvm->srcu);
 649                 ret = kvm_read_guest(kvm, ptbl_addr,
 650                                      &ptbl_entry, sizeof(ptbl_entry));
 651                 srcu_read_unlock(&kvm->srcu, srcu_idx);
 652         }
 653         if (ret) {
 654                 gp->l1_gr_to_hr = 0;
 655                 gp->process_table = 0;
 656         } else {
 657                 gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0);
 658                 gp->process_table = be64_to_cpu(ptbl_entry.patb1);
 659         }
 660         kvmhv_set_nested_ptbl(gp);
 661 }
 662
 663 static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
 664 {
 665         struct kvm_nested_guest *gp;
 666         long shadow_lpid;
 667
 668         gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 669         if (!gp)
 670                 return NULL;
 671         gp->l1_host = kvm;
 672         gp->l1_lpid = lpid;
 673         mutex_init(&gp->tlb_lock);
 674         gp->shadow_pgtable = pgd_alloc(kvm->mm);
 675         if (!gp->shadow_pgtable)
 676                 goto out_free;
 677         shadow_lpid = kvmppc_alloc_lpid();
 678         if (shadow_lpid < 0)
 679                 goto out_free2;
 680         gp->shadow_lpid = shadow_lpid;
 681         gp->radix = 1;
 682
 683         memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu));
 684
 685         return gp;
 686
 687  out_free2:
 688         pgd_free(kvm->mm, gp->shadow_pgtable);
 689  out_free:
 690         kfree(gp);
 691         return NULL;
 692 }
 693
 694 /*
 695  * Free up any resources allocated for a nested guest.
 696  */
 697 static void kvmhv_release_nested(struct kvm_nested_guest *gp)
 698 {
 699         struct kvm *kvm = gp->l1_host;
 700
 701         if (gp->shadow_pgtable) {
 702                 /*
 703                  * No vcpu is using this struct and no call to
 704                  * kvmhv_get_nested can find this struct,
 705                  * so we don't need to hold kvm->mmu_lock.
 706                  */
 707                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
 708                                           gp->shadow_lpid);
 709                 pgd_free(kvm->mm, gp->shadow_pgtable);
 710         }
 711         kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0);
 712         kvmppc_free_lpid(gp->shadow_lpid);
 713         kfree(gp);
 714 }
 715
 716 static void kvmhv_remove_nested(struct kvm_nested_guest *gp)
 717 {
 718         struct kvm *kvm = gp->l1_host;
 719         int lpid = gp->l1_lpid;
 720         long ref;
 721
 722         spin_lock(&kvm->mmu_lock);
 723         if (gp == kvm->arch.nested_guests[lpid]) {
 724                 kvm->arch.nested_guests[lpid] = NULL;
 725                 if (lpid == kvm->arch.max_nested_lpid) {
 726                         while (--lpid >= 0 && !kvm->arch.nested_guests[lpid])
 727                                 ;
 728                         kvm->arch.max_nested_lpid = lpid;
 729                 }
 730                 --gp->refcnt;
 731         }
 732         ref = gp->refcnt;
 733         spin_unlock(&kvm->mmu_lock);
 734         if (ref == 0)
 735                 kvmhv_release_nested(gp);
 736 }
 737
 738 /*
 739  * Free up all nested resources allocated for this guest.
 740  * This is called with no vcpus of the guest running, when
 741  * switching the guest to HPT mode or when destroying the
 742  * guest.
 743  */
 744 void kvmhv_release_all_nested(struct kvm *kvm)
 745 {
 746         int i;
 747         struct kvm_nested_guest *gp;
 748         struct kvm_nested_guest *freelist = NULL;
 749         struct kvm_memory_slot *memslot;
 750         int srcu_idx, bkt;
 751
 752         spin_lock(&kvm->mmu_lock);
 753         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
 754                 gp = kvm->arch.nested_guests[i];
 755                 if (!gp)
 756                         continue;
 757                 kvm->arch.nested_guests[i] = NULL;
 758                 if (--gp->refcnt == 0) {
 759                         gp->next = freelist;
 760                         freelist = gp;
 761                 }
 762         }
 763         kvm->arch.max_nested_lpid = -1;
 764         spin_unlock(&kvm->mmu_lock);
 765         while ((gp = freelist) != NULL) {
 766                 freelist = gp->next;
 767                 kvmhv_release_nested(gp);
 768         }
 769
 770         srcu_idx = srcu_read_lock(&kvm->srcu);
 771         kvm_for_each_memslot(memslot, bkt, kvm_memslots(kvm))
 772                 kvmhv_free_memslot_nest_rmap(memslot);
 773         srcu_read_unlock(&kvm->srcu, srcu_idx);
 774 }
 775
 776 /* caller must hold gp->tlb_lock */
 777 static void kvmhv_flush_nested(struct kvm_nested_guest *gp)
 778 {
 779         struct kvm *kvm = gp->l1_host;
 780
 781         spin_lock(&kvm->mmu_lock);
 782         kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid);
 783         spin_unlock(&kvm->mmu_lock);
 784         kvmhv_flush_lpid(gp->shadow_lpid);
 785         kvmhv_update_ptbl_cache(gp);
 786         if (gp->l1_gr_to_hr == 0)
 787                 kvmhv_remove_nested(gp);
 788 }
 789
 790 struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
 791                                           bool create)
 792 {
 793         struct kvm_nested_guest *gp, *newgp;
 794
 795         if (l1_lpid >= KVM_MAX_NESTED_GUESTS ||
 796             l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4)))
 797                 return NULL;
 798
 799         spin_lock(&kvm->mmu_lock);
 800         gp = kvm->arch.nested_guests[l1_lpid];
 801         if (gp)
 802                 ++gp->refcnt;
 803         spin_unlock(&kvm->mmu_lock);
 804
 805         if (gp || !create)
 806                 return gp;
 807
 808         newgp = kvmhv_alloc_nested(kvm, l1_lpid);
 809         if (!newgp)
 810                 return NULL;
 811         spin_lock(&kvm->mmu_lock);
 812         if (kvm->arch.nested_guests[l1_lpid]) {
 813                 /* someone else beat us to it */
 814                 gp = kvm->arch.nested_guests[l1_lpid];
 815         } else {
 816                 kvm->arch.nested_guests[l1_lpid] = newgp;
 817                 ++newgp->refcnt;
 818                 gp = newgp;
 819                 newgp = NULL;
 820                 if (l1_lpid > kvm->arch.max_nested_lpid)
 821                         kvm->arch.max_nested_lpid = l1_lpid;
 822         }
 823         ++gp->refcnt;
 824         spin_unlock(&kvm->mmu_lock);
 825
 826         if (newgp)
 827                 kvmhv_release_nested(newgp);
 828
 829         return gp;
 830 }
 831
 832 void kvmhv_put_nested(struct kvm_nested_guest *gp)
 833 {
 834         struct kvm *kvm = gp->l1_host;
 835         long ref;
 836
 837         spin_lock(&kvm->mmu_lock);
 838         ref = --gp->refcnt;
 839         spin_unlock(&kvm->mmu_lock);
 840         if (ref == 0)
 841                 kvmhv_release_nested(gp);
 842 }
 843
 844 static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid)
 845 {
 846         if (lpid > kvm->arch.max_nested_lpid)
 847                 return NULL;
 848         return kvm->arch.nested_guests[lpid];
 849 }
 850
 851 pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid,
 852                                  unsigned long ea, unsigned *hshift)
 853 {
 854         struct kvm_nested_guest *gp;
 855         pte_t *pte;
 856
 857         gp = kvmhv_find_nested(kvm, lpid);
 858         if (!gp)
 859                 return NULL;
 860
 861         VM_WARN(!spin_is_locked(&kvm->mmu_lock),
 862                 "%s called with kvm mmu_lock not held \n", __func__);
 863         pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift);
 864
 865         return pte;
 866 }
 867
 868 static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2)
 869 {
 870         return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK |
 871                                        RMAP_NESTED_GPA_MASK));
 872 }
 873
 874 void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
 875                             struct rmap_nested **n_rmap)
 876 {
 877         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 878         struct rmap_nested *cursor;
 879         u64 rmap, new_rmap = (*n_rmap)->rmap;
 880
 881         /* Are there any existing entries? */
 882         if (!(*rmapp)) {
 883                 /* No -> use the rmap as a single entry */
 884                 *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY;
 885                 return;
 886         }
 887
 888         /* Do any entries match what we're trying to insert? */
 889         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 890                 if (kvmhv_n_rmap_is_equal(rmap, new_rmap))
 891                         return;
 892         }
 893
 894         /* Do we need to create a list or just add the new entry? */
 895         rmap = *rmapp;
 896         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 897                 *rmapp = 0UL;
 898         llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp);
 899         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 900                 (*n_rmap)->list.next = (struct llist_node *) rmap;
 901
 902         /* Set NULL so not freed by caller */
 903         *n_rmap = NULL;
 904 }
 905
 906 static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap,
 907                                       unsigned long clr, unsigned long set,
 908                                       unsigned long hpa, unsigned long mask)
 909 {
 910         unsigned long gpa;
 911         unsigned int shift, lpid;
 912         pte_t *ptep;
 913
 914         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 915         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 916
 917         /* Find the pte */
 918         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 919         /*
 920          * If the pte is present and the pfn is still the same, update the pte.
 921          * If the pfn has changed then this is a stale rmap entry, the nested
 922          * gpa actually points somewhere else now, and there is nothing to do.
 923          * XXX A future optimisation would be to remove the rmap entry here.
 924          */
 925         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) {
 926                 __radix_pte_update(ptep, clr, set);
 927                 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
 928         }
 929 }
 930
 931 /*
 932  * For a given list of rmap entries, update the rc bits in all ptes in shadow
 933  * page tables for nested guests which are referenced by the rmap list.
 934  */
 935 void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp,
 936                                     unsigned long clr, unsigned long set,
 937                                     unsigned long hpa, unsigned long nbytes)
 938 {
 939         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 940         struct rmap_nested *cursor;
 941         unsigned long rmap, mask;
 942
 943         if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED))
 944                 return;
 945
 946         mask = PTE_RPN_MASK & ~(nbytes - 1);
 947         hpa &= mask;
 948
 949         for_each_nest_rmap_safe(cursor, entry, &rmap)
 950                 kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask);
 951 }
 952
 953 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
 954                                    unsigned long hpa, unsigned long mask)
 955 {
 956         struct kvm_nested_guest *gp;
 957         unsigned long gpa;
 958         unsigned int shift, lpid;
 959         pte_t *ptep;
 960
 961         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 962         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 963         gp = kvmhv_find_nested(kvm, lpid);
 964         if (!gp)
 965                 return;
 966
 967         /* Find and invalidate the pte */
 968         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 969         /* Don't spuriously invalidate ptes if the pfn has changed */
 970         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa))
 971                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
 972 }
 973
 974 static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
 975                                         unsigned long hpa, unsigned long mask)
 976 {
 977         struct llist_node *entry = llist_del_all((struct llist_head *) rmapp);
 978         struct rmap_nested *cursor;
 979         unsigned long rmap;
 980
 981         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 982                 kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask);
 983                 kfree(cursor);
 984         }
 985 }
 986
 987 /* called with kvm->mmu_lock held */
 988 void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
 989                                   const struct kvm_memory_slot *memslot,
 990                                   unsigned long gpa, unsigned long hpa,
 991                                   unsigned long nbytes)
 992 {
 993         unsigned long gfn, end_gfn;
 994         unsigned long addr_mask;
 995
 996         if (!memslot)
 997                 return;
 998         gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn;
 999         end_gfn = gfn + (nbytes >> PAGE_SHIFT);
1000
1001         addr_mask = PTE_RPN_MASK & ~(nbytes - 1);
1002         hpa &= addr_mask;
1003
1004         for (; gfn < end_gfn; gfn++) {
1005                 unsigned long *rmap = &memslot->arch.rmap[gfn];
1006                 kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask);
1007         }
1008 }
1009
1010 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free)
1011 {
1012         unsigned long page;
1013
1014         for (page = 0; page < free->npages; page++) {
1015                 unsigned long rmap, *rmapp = &free->arch.rmap[page];
1016                 struct rmap_nested *cursor;
1017                 struct llist_node *entry;
1018
1019                 entry = llist_del_all((struct llist_head *) rmapp);
1020                 for_each_nest_rmap_safe(cursor, entry, &rmap)
1021                         kfree(cursor);
1022         }
1023 }
1024
1025 static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu,
1026                                         struct kvm_nested_guest *gp,
1027                                         long gpa, int *shift_ret)
1028 {
1029         struct kvm *kvm = vcpu->kvm;
1030         bool ret = false;
1031         pte_t *ptep;
1032         int shift;
1033
1034         spin_lock(&kvm->mmu_lock);
1035         ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift);
1036         if (!shift)
1037                 shift = PAGE_SHIFT;
1038         if (ptep && pte_present(*ptep)) {
1039                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
1040                 ret = true;
1041         }
1042         spin_unlock(&kvm->mmu_lock);
1043
1044         if (shift_ret)
1045                 *shift_ret = shift;
1046         return ret;
1047 }
1048
1049 static inline int get_ric(unsigned int instr)
1050 {
1051         return (instr >> 18) & 0x3;
1052 }
1053
1054 static inline int get_prs(unsigned int instr)
1055 {
1056         return (instr >> 17) & 0x1;
1057 }
1058
1059 static inline int get_r(unsigned int instr)
1060 {
1061         return (instr >> 16) & 0x1;
1062 }
1063
1064 static inline int get_lpid(unsigned long r_val)
1065 {
1066         return r_val & 0xffffffff;
1067 }
1068
1069 static inline int get_is(unsigned long r_val)
1070 {
1071         return (r_val >> 10) & 0x3;
1072 }
1073
1074 static inline int get_ap(unsigned long r_val)
1075 {
1076         return (r_val >> 5) & 0x7;
1077 }
1078
1079 static inline long get_epn(unsigned long r_val)
1080 {
1081         return r_val >> 12;
1082 }
1083
1084 static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid,
1085                                         int ap, long epn)
1086 {
1087         struct kvm *kvm = vcpu->kvm;
1088         struct kvm_nested_guest *gp;
1089         long npages;
1090         int shift, shadow_shift;
1091         unsigned long addr;
1092
1093         shift = ap_to_shift(ap);
1094         addr = epn << 12;
1095         if (shift < 0)
1096                 /* Invalid ap encoding */
1097                 return -EINVAL;
1098
1099         addr &= ~((1UL << shift) - 1);
1100         npages = 1UL << (shift - PAGE_SHIFT);
1101
1102         gp = kvmhv_get_nested(kvm, lpid, false);
1103         if (!gp) /* No such guest -> nothing to do */
1104                 return 0;
1105         mutex_lock(&gp->tlb_lock);
1106
1107         /* There may be more than one host page backing this single guest pte */
1108         do {
1109                 kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift);
1110
1111                 npages -= 1UL << (shadow_shift - PAGE_SHIFT);
1112                 addr += 1UL << shadow_shift;
1113         } while (npages > 0);
1114
1115         mutex_unlock(&gp->tlb_lock);
1116         kvmhv_put_nested(gp);
1117         return 0;
1118 }
1119
1120 static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu,
1121                                      struct kvm_nested_guest *gp, int ric)
1122 {
1123         struct kvm *kvm = vcpu->kvm;
1124
1125         mutex_lock(&gp->tlb_lock);
1126         switch (ric) {
1127         case 0:
1128                 /* Invalidate TLB */
1129                 spin_lock(&kvm->mmu_lock);
1130                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
1131                                           gp->shadow_lpid);
1132                 kvmhv_flush_lpid(gp->shadow_lpid);
1133                 spin_unlock(&kvm->mmu_lock);
1134                 break;
1135         case 1:
1136                 /*
1137                  * Invalidate PWC
1138                  * We don't cache this -> nothing to do
1139                  */
1140                 break;
1141         case 2:
1142                 /* Invalidate TLB, PWC and caching of partition table entries */
1143                 kvmhv_flush_nested(gp);
1144                 break;
1145         default:
1146                 break;
1147         }
1148         mutex_unlock(&gp->tlb_lock);
1149 }
1150
1151 static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric)
1152 {
1153         struct kvm *kvm = vcpu->kvm;
1154         struct kvm_nested_guest *gp;
1155         int i;
1156
1157         spin_lock(&kvm->mmu_lock);
1158         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
1159                 gp = kvm->arch.nested_guests[i];
1160                 if (gp) {
1161                         spin_unlock(&kvm->mmu_lock);
1162                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1163                         spin_lock(&kvm->mmu_lock);
1164                 }
1165         }
1166         spin_unlock(&kvm->mmu_lock);
1167 }
1168
1169 static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr,
1170                                     unsigned long rsval, unsigned long rbval)
1171 {
1172         struct kvm *kvm = vcpu->kvm;
1173         struct kvm_nested_guest *gp;
1174         int r, ric, prs, is, ap;
1175         int lpid;
1176         long epn;
1177         int ret = 0;
1178
1179         ric = get_ric(instr);
1180         prs = get_prs(instr);
1181         r = get_r(instr);
1182         lpid = get_lpid(rsval);
1183         is = get_is(rbval);
1184
1185         /*
1186          * These cases are invalid and are not handled:
1187          * r   != 1 -> Only radix supported
1188          * prs == 1 -> Not HV privileged
1189          * ric == 3 -> No cluster bombs for radix
1190          * is  == 1 -> Partition scoped translations not associated with pid
1191          * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA
1192          */
1193         if ((!r) || (prs) || (ric == 3) || (is == 1) ||
1194             ((!is) && (ric == 1 || ric == 2)))
1195                 return -EINVAL;
1196
1197         switch (is) {
1198         case 0:
1199                 /*
1200                  * We know ric == 0
1201                  * Invalidate TLB for a given target address
1202                  */
1203                 epn = get_epn(rbval);
1204                 ap = get_ap(rbval);
1205                 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn);
1206                 break;
1207         case 2:
1208                 /* Invalidate matching LPID */
1209                 gp = kvmhv_get_nested(kvm, lpid, false);
1210                 if (gp) {
1211                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1212                         kvmhv_put_nested(gp);
1213                 }
1214                 break;
1215         case 3:
1216                 /* Invalidate ALL LPIDs */
1217                 kvmhv_emulate_tlbie_all_lpid(vcpu, ric);
1218                 break;
1219         default:
1220                 ret = -EINVAL;
1221                 break;
1222         }
1223
1224         return ret;
1225 }
1226
1227 /*
1228  * This handles the H_TLB_INVALIDATE hcall.
1229  * Parameters are (r4) tlbie instruction code, (r5) rS contents,
1230  * (r6) rB contents.
1231  */
1232 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
1233 {
1234         int ret;
1235
1236         ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4),
1237                         kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6));
1238         if (ret)
1239                 return H_PARAMETER;
1240         return H_SUCCESS;
1241 }
1242
1243 static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
1244                                          unsigned long lpid, unsigned long ric)
1245 {
1246         struct kvm *kvm = vcpu->kvm;
1247         struct kvm_nested_guest *gp;
1248
1249         gp = kvmhv_get_nested(kvm, lpid, false);
1250         if (gp) {
1251                 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1252                 kvmhv_put_nested(gp);
1253         }
1254         return H_SUCCESS;
1255 }
1256
1257 /*
1258  * Number of pages above which we invalidate the entire LPID rather than
1259  * flush individual pages.
1260  */
1261 static unsigned long tlb_range_flush_page_ceiling __read_mostly = 33;
1262
1263 static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
1264                                          unsigned long lpid,
1265                                          unsigned long pg_sizes,
1266                                          unsigned long start,
1267                                          unsigned long end)
1268 {
1269         int ret = H_P4;
1270         unsigned long addr, nr_pages;
1271         struct mmu_psize_def *def;
1272         unsigned long psize, ap, page_size;
1273         bool flush_lpid;
1274
1275         for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
1276                 def = &mmu_psize_defs[psize];
1277                 if (!(pg_sizes & def->h_rpt_pgsize))
1278                         continue;
1279
1280                 nr_pages = (end - start) >> def->shift;
1281                 flush_lpid = nr_pages > tlb_range_flush_page_ceiling;
1282                 if (flush_lpid)
1283                         return do_tlb_invalidate_nested_all(vcpu, lpid,
1284                                                         RIC_FLUSH_TLB);
1285                 addr = start;
1286                 ap = mmu_get_ap(psize);
1287                 page_size = 1UL << def->shift;
1288                 do {
1289                         ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
1290                                                    get_epn(addr));
1291                         if (ret)
1292                                 return H_P4;
1293                         addr += page_size;
1294                 } while (addr < end);
1295         }
1296         return ret;
1297 }
1298
1299 /*
1300  * Performs partition-scoped invalidations for nested guests
1301  * as part of H_RPT_INVALIDATE hcall.
1302  */
1303 long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
1304                              unsigned long type, unsigned long pg_sizes,
1305                              unsigned long start, unsigned long end)
1306 {
1307         /*
1308          * If L2 lpid isn't valid, we need to return H_PARAMETER.
1309          *
1310          * However, nested KVM issues a L2 lpid flush call when creating
1311          * partition table entries for L2. This happens even before the
1312          * corresponding shadow lpid is created in HV which happens in
1313          * H_ENTER_NESTED call. Since we can't differentiate this case from
1314          * the invalid case, we ignore such flush requests and return success.
1315          */
1316         if (!kvmhv_find_nested(vcpu->kvm, lpid))
1317                 return H_SUCCESS;
1318
1319         /*
1320          * A flush all request can be handled by a full lpid flush only.
1321          */
1322         if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
1323                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
1324
1325         /*
1326          * We don't need to handle a PWC flush like process table here,
1327          * because intermediate partition scoped table in nested guest doesn't
1328          * really have PWC. Only level we have PWC is in L0 and for nested
1329          * invalidate at L0 we always do kvm_flush_lpid() which does
1330          * radix__flush_all_lpid(). For range invalidate at any level, we
1331          * are not removing the higher level page tables and hence there is
1332          * no PWC invalidate needed.
1333          *
1334          * if (type & H_RPTI_TYPE_PWC) {
1335          *      ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
1336          *      if (ret)
1337          *              return H_P4;
1338          * }
1339          */
1340
1341         if (start == 0 && end == -1)
1342                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
1343
1344         if (type & H_RPTI_TYPE_TLB)
1345                 return do_tlb_invalidate_nested_tlb(vcpu, lpid, pg_sizes,
1346                                                     start, end);
1347         return H_SUCCESS;
1348 }
1349
1350 /* Used to convert a nested guest real address to a L1 guest real address */
1351 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
1352                                        struct kvm_nested_guest *gp,
1353                                        unsigned long n_gpa, unsigned long dsisr,
1354                                        struct kvmppc_pte *gpte_p)
1355 {
1356         u64 fault_addr, flags = dsisr & DSISR_ISSTORE;
1357         int ret;
1358
1359         ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr,
1360                                          &fault_addr);
1361
1362         if (ret) {
1363                 /* We didn't find a pte */
1364                 if (ret == -EINVAL) {
1365                         /* Unsupported mmu config */
1366                         flags |= DSISR_UNSUPP_MMU;
1367                 } else if (ret == -ENOENT) {
1368                         /* No translation found */
1369                         flags |= DSISR_NOHPTE;
1370                 } else if (ret == -EFAULT) {
1371                         /* Couldn't access L1 real address */
1372                         flags |= DSISR_PRTABLE_FAULT;
1373                         vcpu->arch.fault_gpa = fault_addr;
1374                 } else {
1375                         /* Unknown error */
1376                         return ret;
1377                 }
1378                 goto forward_to_l1;
1379         } else {
1380                 /* We found a pte -> check permissions */
1381                 if (dsisr & DSISR_ISSTORE) {
1382                         /* Can we write? */
1383                         if (!gpte_p->may_write) {
1384                                 flags |= DSISR_PROTFAULT;
1385                                 goto forward_to_l1;
1386                         }
1387                 } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1388                         /* Can we execute? */
1389                         if (!gpte_p->may_execute) {
1390                                 flags |= SRR1_ISI_N_G_OR_CIP;
1391                                 goto forward_to_l1;
1392                         }
1393                 } else {
1394                         /* Can we read? */
1395                         if (!gpte_p->may_read && !gpte_p->may_write) {
1396                                 flags |= DSISR_PROTFAULT;
1397                                 goto forward_to_l1;
1398                         }
1399                 }
1400         }
1401
1402         return 0;
1403
1404 forward_to_l1:
1405         vcpu->arch.fault_dsisr = flags;
1406         if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1407                 vcpu->arch.shregs.msr &= SRR1_MSR_BITS;
1408                 vcpu->arch.shregs.msr |= flags;
1409         }
1410         return RESUME_HOST;
1411 }
1412
1413 static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
1414                                        struct kvm_nested_guest *gp,
1415                                        unsigned long n_gpa,
1416                                        struct kvmppc_pte gpte,
1417                                        unsigned long dsisr)
1418 {
1419         struct kvm *kvm = vcpu->kvm;
1420         bool writing = !!(dsisr & DSISR_ISSTORE);
1421         u64 pgflags;
1422         long ret;
1423
1424         /* Are the rc bits set in the L1 partition scoped pte? */
1425         pgflags = _PAGE_ACCESSED;
1426         if (writing)
1427                 pgflags |= _PAGE_DIRTY;
1428         if (pgflags & ~gpte.rc)
1429                 return RESUME_HOST;
1430
1431         spin_lock(&kvm->mmu_lock);
1432         /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
1433         ret = kvmppc_hv_handle_set_rc(kvm, false, writing,
1434                                       gpte.raddr, kvm->arch.lpid);
1435         if (!ret) {
1436                 ret = -EINVAL;
1437                 goto out_unlock;
1438         }
1439
1440         /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
1441         ret = kvmppc_hv_handle_set_rc(kvm, true, writing,
1442                                       n_gpa, gp->l1_lpid);
1443         if (!ret)
1444                 ret = -EINVAL;
1445         else
1446                 ret = 0;
1447
1448 out_unlock:
1449         spin_unlock(&kvm->mmu_lock);
1450         return ret;
1451 }
1452
1453 static inline int kvmppc_radix_level_to_shift(int level)
1454 {
1455         switch (level) {
1456         case 2:
1457                 return PUD_SHIFT;
1458         case 1:
1459                 return PMD_SHIFT;
1460         default:
1461                 return PAGE_SHIFT;
1462         }
1463 }
1464
1465 static inline int kvmppc_radix_shift_to_level(int shift)
1466 {
1467         if (shift == PUD_SHIFT)
1468                 return 2;
1469         if (shift == PMD_SHIFT)
1470                 return 1;
1471         if (shift == PAGE_SHIFT)
1472                 return 0;
1473         WARN_ON_ONCE(1);
1474         return 0;
1475 }
1476
1477 /* called with gp->tlb_lock held */
1478 static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
1479                                           struct kvm_nested_guest *gp)
1480 {
1481         struct kvm *kvm = vcpu->kvm;
1482         struct kvm_memory_slot *memslot;
1483         struct rmap_nested *n_rmap;
1484         struct kvmppc_pte gpte;
1485         pte_t pte, *pte_p;
1486         unsigned long mmu_seq;
1487         unsigned long dsisr = vcpu->arch.fault_dsisr;
1488         unsigned long ea = vcpu->arch.fault_dar;
1489         unsigned long *rmapp;
1490         unsigned long n_gpa, gpa, gfn, perm = 0UL;
1491         unsigned int shift, l1_shift, level;
1492         bool writing = !!(dsisr & DSISR_ISSTORE);
1493         bool kvm_ro = false;
1494         long int ret;
1495
1496         if (!gp->l1_gr_to_hr) {
1497                 kvmhv_update_ptbl_cache(gp);
1498                 if (!gp->l1_gr_to_hr)
1499                         return RESUME_HOST;
1500         }
1501
1502         /* Convert the nested guest real address into a L1 guest real address */
1503
1504         n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL;
1505         if (!(dsisr & DSISR_PRTABLE_FAULT))
1506                 n_gpa |= ea & 0xFFF;
1507         ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte);
1508
1509         /*
1510          * If the hardware found a translation but we don't now have a usable
1511          * translation in the l1 partition-scoped tree, remove the shadow pte
1512          * and let the guest retry.
1513          */
1514         if (ret == RESUME_HOST &&
1515             (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G |
1516                       DSISR_BAD_COPYPASTE)))
1517                 goto inval;
1518         if (ret)
1519                 return ret;
1520
1521         /* Failed to set the reference/change bits */
1522         if (dsisr & DSISR_SET_RC) {
1523                 ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr);
1524                 if (ret == RESUME_HOST)
1525                         return ret;
1526                 if (ret)
1527                         goto inval;
1528                 dsisr &= ~DSISR_SET_RC;
1529                 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
1530                                DSISR_PROTFAULT)))
1531                         return RESUME_GUEST;
1532         }
1533
1534         /*
1535          * We took an HISI or HDSI while we were running a nested guest which
1536          * means we have no partition scoped translation for that. This means
1537          * we need to insert a pte for the mapping into our shadow_pgtable.
1538          */
1539
1540         l1_shift = gpte.page_shift;
1541         if (l1_shift < PAGE_SHIFT) {
1542                 /* We don't support l1 using a page size smaller than our own */
1543                 pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n",
1544                         l1_shift, PAGE_SHIFT);
1545                 return -EINVAL;
1546         }
1547         gpa = gpte.raddr;
1548         gfn = gpa >> PAGE_SHIFT;
1549
1550         /* 1. Get the corresponding host memslot */
1551
1552         memslot = gfn_to_memslot(kvm, gfn);
1553         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
1554                 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) {
1555                         /* unusual error -> reflect to the guest as a DSI */
1556                         kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
1557                         return RESUME_GUEST;
1558                 }
1559
1560                 /* passthrough of emulated MMIO case */
1561                 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing);
1562         }
1563         if (memslot->flags & KVM_MEM_READONLY) {
1564                 if (writing) {
1565                         /* Give the guest a DSI */
1566                         kvmppc_core_queue_data_storage(vcpu, ea,
1567                                         DSISR_ISSTORE | DSISR_PROTFAULT);
1568                         return RESUME_GUEST;
1569                 }
1570                 kvm_ro = true;
1571         }
1572
1573         /* 2. Find the host pte for this L1 guest real address */
1574
1575         /* Used to check for invalidations in progress */
1576         mmu_seq = kvm->mmu_notifier_seq;
1577         smp_rmb();
1578
1579         /* See if can find translation in our partition scoped tables for L1 */
1580         pte = __pte(0);
1581         spin_lock(&kvm->mmu_lock);
1582         pte_p = find_kvm_secondary_pte(kvm, gpa, &shift);
1583         if (!shift)
1584                 shift = PAGE_SHIFT;
1585         if (pte_p)
1586                 pte = *pte_p;
1587         spin_unlock(&kvm->mmu_lock);
1588
1589         if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) {
1590                 /* No suitable pte found -> try to insert a mapping */
1591                 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot,
1592                                         writing, kvm_ro, &pte, &level);
1593                 if (ret == -EAGAIN)
1594                         return RESUME_GUEST;
1595                 else if (ret)
1596                         return ret;
1597                 shift = kvmppc_radix_level_to_shift(level);
1598         }
1599         /* Align gfn to the start of the page */
1600         gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT;
1601
1602         /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */
1603
1604         /* The permissions is the combination of the host and l1 guest ptes */
1605         perm |= gpte.may_read ? 0UL : _PAGE_READ;
1606         perm |= gpte.may_write ? 0UL : _PAGE_WRITE;
1607         perm |= gpte.may_execute ? 0UL : _PAGE_EXEC;
1608         /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */
1609         perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED;
1610         perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY;
1611         pte = __pte(pte_val(pte) & ~perm);
1612
1613         /* What size pte can we insert? */
1614         if (shift > l1_shift) {
1615                 u64 mask;
1616                 unsigned int actual_shift = PAGE_SHIFT;
1617                 if (PMD_SHIFT < l1_shift)
1618                         actual_shift = PMD_SHIFT;
1619                 mask = (1UL << shift) - (1UL << actual_shift);
1620                 pte = __pte(pte_val(pte) | (gpa & mask));
1621                 shift = actual_shift;
1622         }
1623         level = kvmppc_radix_shift_to_level(shift);
1624         n_gpa &= ~((1UL << shift) - 1);
1625
1626         /* 4. Insert the pte into our shadow_pgtable */
1627
1628         n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL);
1629         if (!n_rmap)
1630                 return RESUME_GUEST; /* Let the guest try again */
1631         n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) |
1632                 (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT);
1633         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1634         ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level,
1635                                 mmu_seq, gp->shadow_lpid, rmapp, &n_rmap);
1636         kfree(n_rmap);
1637         if (ret == -EAGAIN)
1638                 ret = RESUME_GUEST;     /* Let the guest try again */
1639
1640         return ret;
1641
1642  inval:
1643         kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL);
1644         return RESUME_GUEST;
1645 }
1646
1647 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu)
1648 {
1649         struct kvm_nested_guest *gp = vcpu->arch.nested;
1650         long int ret;
1651
1652         mutex_lock(&gp->tlb_lock);
1653         ret = __kvmhv_nested_page_fault(vcpu, gp);
1654         mutex_unlock(&gp->tlb_lock);
1655         return ret;
1656 }
1657
1658 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid)
1659 {
1660         int ret = -1;
1661
1662         spin_lock(&kvm->mmu_lock);
1663         while (++lpid <= kvm->arch.max_nested_lpid) {
1664                 if (kvm->arch.nested_guests[lpid]) {
1665                         ret = lpid;
1666                         break;
1667                 }
1668         }
1669         spin_unlock(&kvm->mmu_lock);
1670         return ret;
1671 }