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, int trap,
 103                                  struct hv_guest_state *hr)
 104 {
 105         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 106
 107         hr->dpdes = vc->dpdes;
 108         hr->hfscr = vcpu->arch.hfscr;
 109         hr->purr = vcpu->arch.purr;
 110         hr->spurr = vcpu->arch.spurr;
 111         hr->ic = vcpu->arch.ic;
 112         hr->vtb = vc->vtb;
 113         hr->srr0 = vcpu->arch.shregs.srr0;
 114         hr->srr1 = vcpu->arch.shregs.srr1;
 115         hr->sprg[0] = vcpu->arch.shregs.sprg0;
 116         hr->sprg[1] = vcpu->arch.shregs.sprg1;
 117         hr->sprg[2] = vcpu->arch.shregs.sprg2;
 118         hr->sprg[3] = vcpu->arch.shregs.sprg3;
 119         hr->pidr = vcpu->arch.pid;
 120         hr->cfar = vcpu->arch.cfar;
 121         hr->ppr = vcpu->arch.ppr;
 122         switch (trap) {
 123         case BOOK3S_INTERRUPT_H_DATA_STORAGE:
 124                 hr->hdar = vcpu->arch.fault_dar;
 125                 hr->hdsisr = vcpu->arch.fault_dsisr;
 126                 hr->asdr = vcpu->arch.fault_gpa;
 127                 break;
 128         case BOOK3S_INTERRUPT_H_INST_STORAGE:
 129                 hr->asdr = vcpu->arch.fault_gpa;
 130                 break;
 131         case BOOK3S_INTERRUPT_H_EMUL_ASSIST:
 132                 hr->heir = vcpu->arch.emul_inst;
 133                 break;
 134         }
 135 }
 136
 137 /*
 138  * This can result in some L0 HV register state being leaked to an L1
 139  * hypervisor when the hv_guest_state is copied back to the guest after
 140  * being modified here.
 141  *
 142  * There is no known problem with such a leak, and in many cases these
 143  * register settings could be derived by the guest by observing behaviour
 144  * and timing, interrupts, etc., but it is an issue to consider.
 145  */
 146 static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
 147 {
 148         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 149         u64 mask;
 150
 151         /*
 152          * Don't let L1 change LPCR bits for the L2 except these:
 153          */
 154         mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD |
 155                 LPCR_LPES | LPCR_MER;
 156
 157         /*
 158          * Additional filtering is required depending on hardware
 159          * and configuration.
 160          */
 161         hr->lpcr = kvmppc_filter_lpcr_hv(vcpu->kvm,
 162                         (vc->lpcr & ~mask) | (hr->lpcr & mask));
 163
 164         /*
 165          * Don't let L1 enable features for L2 which we've disabled for L1,
 166          * but preserve the interrupt cause field.
 167          */
 168         hr->hfscr &= (HFSCR_INTR_CAUSE | vcpu->arch.hfscr);
 169
 170         /* Don't let data address watchpoint match in hypervisor state */
 171         hr->dawrx0 &= ~DAWRX_HYP;
 172         hr->dawrx1 &= ~DAWRX_HYP;
 173
 174         /* Don't let completed instruction address breakpt match in HV state */
 175         if ((hr->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER)
 176                 hr->ciabr &= ~CIABR_PRIV;
 177 }
 178
 179 static void restore_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
 180 {
 181         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 182
 183         vc->pcr = hr->pcr | PCR_MASK;
 184         vc->dpdes = hr->dpdes;
 185         vcpu->arch.hfscr = hr->hfscr;
 186         vcpu->arch.dawr0 = hr->dawr0;
 187         vcpu->arch.dawrx0 = hr->dawrx0;
 188         vcpu->arch.ciabr = hr->ciabr;
 189         vcpu->arch.purr = hr->purr;
 190         vcpu->arch.spurr = hr->spurr;
 191         vcpu->arch.ic = hr->ic;
 192         vc->vtb = hr->vtb;
 193         vcpu->arch.shregs.srr0 = hr->srr0;
 194         vcpu->arch.shregs.srr1 = hr->srr1;
 195         vcpu->arch.shregs.sprg0 = hr->sprg[0];
 196         vcpu->arch.shregs.sprg1 = hr->sprg[1];
 197         vcpu->arch.shregs.sprg2 = hr->sprg[2];
 198         vcpu->arch.shregs.sprg3 = hr->sprg[3];
 199         vcpu->arch.pid = hr->pidr;
 200         vcpu->arch.cfar = hr->cfar;
 201         vcpu->arch.ppr = hr->ppr;
 202         vcpu->arch.dawr1 = hr->dawr1;
 203         vcpu->arch.dawrx1 = hr->dawrx1;
 204 }
 205
 206 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
 207                                    struct hv_guest_state *hr)
 208 {
 209         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 210
 211         vc->dpdes = hr->dpdes;
 212         vcpu->arch.hfscr = hr->hfscr;
 213         vcpu->arch.purr = hr->purr;
 214         vcpu->arch.spurr = hr->spurr;
 215         vcpu->arch.ic = hr->ic;
 216         vc->vtb = hr->vtb;
 217         vcpu->arch.fault_dar = hr->hdar;
 218         vcpu->arch.fault_dsisr = hr->hdsisr;
 219         vcpu->arch.fault_gpa = hr->asdr;
 220         vcpu->arch.emul_inst = hr->heir;
 221         vcpu->arch.shregs.srr0 = hr->srr0;
 222         vcpu->arch.shregs.srr1 = hr->srr1;
 223         vcpu->arch.shregs.sprg0 = hr->sprg[0];
 224         vcpu->arch.shregs.sprg1 = hr->sprg[1];
 225         vcpu->arch.shregs.sprg2 = hr->sprg[2];
 226         vcpu->arch.shregs.sprg3 = hr->sprg[3];
 227         vcpu->arch.pid = hr->pidr;
 228         vcpu->arch.cfar = hr->cfar;
 229         vcpu->arch.ppr = hr->ppr;
 230 }
 231
 232 static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr)
 233 {
 234         /* No need to reflect the page fault to L1, we've handled it */
 235         vcpu->arch.trap = 0;
 236
 237         /*
 238          * Since the L2 gprs have already been written back into L1 memory when
 239          * we complete the mmio, store the L1 memory location of the L2 gpr
 240          * being loaded into by the mmio so that the loaded value can be
 241          * written there in kvmppc_complete_mmio_load()
 242          */
 243         if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR)
 244             && (vcpu->mmio_is_write == 0)) {
 245                 vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr +
 246                                            offsetof(struct pt_regs,
 247                                                     gpr[vcpu->arch.io_gpr]);
 248                 vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR;
 249         }
 250 }
 251
 252 static int kvmhv_read_guest_state_and_regs(struct kvm_vcpu *vcpu,
 253                                            struct hv_guest_state *l2_hv,
 254                                            struct pt_regs *l2_regs,
 255                                            u64 hv_ptr, u64 regs_ptr)
 256 {
 257         int size;
 258
 259         if (kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv->version,
 260                                 sizeof(l2_hv->version)))
 261                 return -1;
 262
 263         if (kvmppc_need_byteswap(vcpu))
 264                 l2_hv->version = swab64(l2_hv->version);
 265
 266         size = hv_guest_state_size(l2_hv->version);
 267         if (size < 0)
 268                 return -1;
 269
 270         return kvm_vcpu_read_guest(vcpu, hv_ptr, l2_hv, size) ||
 271                 kvm_vcpu_read_guest(vcpu, regs_ptr, l2_regs,
 272                                     sizeof(struct pt_regs));
 273 }
 274
 275 static int kvmhv_write_guest_state_and_regs(struct kvm_vcpu *vcpu,
 276                                             struct hv_guest_state *l2_hv,
 277                                             struct pt_regs *l2_regs,
 278                                             u64 hv_ptr, u64 regs_ptr)
 279 {
 280         int size;
 281
 282         size = hv_guest_state_size(l2_hv->version);
 283         if (size < 0)
 284                 return -1;
 285
 286         return kvm_vcpu_write_guest(vcpu, hv_ptr, l2_hv, size) ||
 287                 kvm_vcpu_write_guest(vcpu, regs_ptr, l2_regs,
 288                                      sizeof(struct pt_regs));
 289 }
 290
 291 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
 292 {
 293         long int err, r;
 294         struct kvm_nested_guest *l2;
 295         struct pt_regs l2_regs, saved_l1_regs;
 296         struct hv_guest_state l2_hv = {0}, saved_l1_hv;
 297         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 298         u64 hv_ptr, regs_ptr;
 299         u64 hdec_exp;
 300         s64 delta_purr, delta_spurr, delta_ic, delta_vtb;
 301
 302         if (vcpu->kvm->arch.l1_ptcr == 0)
 303                 return H_NOT_AVAILABLE;
 304
 305         /* copy parameters in */
 306         hv_ptr = kvmppc_get_gpr(vcpu, 4);
 307         regs_ptr = kvmppc_get_gpr(vcpu, 5);
 308         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 309         err = kvmhv_read_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 310                                               hv_ptr, regs_ptr);
 311         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 312         if (err)
 313                 return H_PARAMETER;
 314
 315         if (kvmppc_need_byteswap(vcpu))
 316                 byteswap_hv_regs(&l2_hv);
 317         if (l2_hv.version > HV_GUEST_STATE_VERSION)
 318                 return H_P2;
 319
 320         if (kvmppc_need_byteswap(vcpu))
 321                 byteswap_pt_regs(&l2_regs);
 322         if (l2_hv.vcpu_token >= NR_CPUS)
 323                 return H_PARAMETER;
 324
 325         /* translate lpid */
 326         l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true);
 327         if (!l2)
 328                 return H_PARAMETER;
 329         if (!l2->l1_gr_to_hr) {
 330                 mutex_lock(&l2->tlb_lock);
 331                 kvmhv_update_ptbl_cache(l2);
 332                 mutex_unlock(&l2->tlb_lock);
 333         }
 334
 335         /* save l1 values of things */
 336         vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
 337         saved_l1_regs = vcpu->arch.regs;
 338         kvmhv_save_hv_regs(vcpu, &saved_l1_hv);
 339
 340         /* convert TB values/offsets to host (L0) values */
 341         hdec_exp = l2_hv.hdec_expiry - vc->tb_offset;
 342         vc->tb_offset += l2_hv.tb_offset;
 343
 344         /* set L1 state to L2 state */
 345         vcpu->arch.nested = l2;
 346         vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token;
 347         vcpu->arch.regs = l2_regs;
 348
 349         /* Guest must always run with ME enabled, HV disabled. */
 350         vcpu->arch.shregs.msr = (vcpu->arch.regs.msr | MSR_ME) & ~MSR_HV;
 351
 352         sanitise_hv_regs(vcpu, &l2_hv);
 353         restore_hv_regs(vcpu, &l2_hv);
 354
 355         vcpu->arch.ret = RESUME_GUEST;
 356         vcpu->arch.trap = 0;
 357         do {
 358                 if (mftb() >= hdec_exp) {
 359                         vcpu->arch.trap = BOOK3S_INTERRUPT_HV_DECREMENTER;
 360                         r = RESUME_HOST;
 361                         break;
 362                 }
 363                 r = kvmhv_run_single_vcpu(vcpu, hdec_exp, l2_hv.lpcr);
 364         } while (is_kvmppc_resume_guest(r));
 365
 366         /* save L2 state for return */
 367         l2_regs = vcpu->arch.regs;
 368         l2_regs.msr = vcpu->arch.shregs.msr;
 369         delta_purr = vcpu->arch.purr - l2_hv.purr;
 370         delta_spurr = vcpu->arch.spurr - l2_hv.spurr;
 371         delta_ic = vcpu->arch.ic - l2_hv.ic;
 372         delta_vtb = vc->vtb - l2_hv.vtb;
 373         save_hv_return_state(vcpu, vcpu->arch.trap, &l2_hv);
 374
 375         /* restore L1 state */
 376         vcpu->arch.nested = NULL;
 377         vcpu->arch.regs = saved_l1_regs;
 378         vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK;
 379         /* set L1 MSR TS field according to L2 transaction state */
 380         if (l2_regs.msr & MSR_TS_MASK)
 381                 vcpu->arch.shregs.msr |= MSR_TS_S;
 382         vc->tb_offset = saved_l1_hv.tb_offset;
 383         restore_hv_regs(vcpu, &saved_l1_hv);
 384         vcpu->arch.purr += delta_purr;
 385         vcpu->arch.spurr += delta_spurr;
 386         vcpu->arch.ic += delta_ic;
 387         vc->vtb += delta_vtb;
 388
 389         kvmhv_put_nested(l2);
 390
 391         /* copy l2_hv_state and regs back to guest */
 392         if (kvmppc_need_byteswap(vcpu)) {
 393                 byteswap_hv_regs(&l2_hv);
 394                 byteswap_pt_regs(&l2_regs);
 395         }
 396         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 397         err = kvmhv_write_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 398                                                hv_ptr, regs_ptr);
 399         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 400         if (err)
 401                 return H_AUTHORITY;
 402
 403         if (r == -EINTR)
 404                 return H_INTERRUPT;
 405
 406         if (vcpu->mmio_needed) {
 407                 kvmhv_nested_mmio_needed(vcpu, regs_ptr);
 408                 return H_TOO_HARD;
 409         }
 410
 411         return vcpu->arch.trap;
 412 }
 413
 414 long kvmhv_nested_init(void)
 415 {
 416         long int ptb_order;
 417         unsigned long ptcr;
 418         long rc;
 419
 420         if (!kvmhv_on_pseries())
 421                 return 0;
 422         if (!radix_enabled())
 423                 return -ENODEV;
 424
 425         /* find log base 2 of KVMPPC_NR_LPIDS, rounding up */
 426         ptb_order = __ilog2(KVMPPC_NR_LPIDS - 1) + 1;
 427         if (ptb_order < 8)
 428                 ptb_order = 8;
 429         pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order,
 430                                        GFP_KERNEL);
 431         if (!pseries_partition_tb) {
 432                 pr_err("kvm-hv: failed to allocated nested partition table\n");
 433                 return -ENOMEM;
 434         }
 435
 436         ptcr = __pa(pseries_partition_tb) | (ptb_order - 8);
 437         rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr);
 438         if (rc != H_SUCCESS) {
 439                 pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n",
 440                        rc);
 441                 kfree(pseries_partition_tb);
 442                 pseries_partition_tb = NULL;
 443                 return -ENODEV;
 444         }
 445
 446         return 0;
 447 }
 448
 449 void kvmhv_nested_exit(void)
 450 {
 451         /*
 452          * N.B. the kvmhv_on_pseries() test is there because it enables
 453          * the compiler to remove the call to plpar_hcall_norets()
 454          * when CONFIG_PPC_PSERIES=n.
 455          */
 456         if (kvmhv_on_pseries() && pseries_partition_tb) {
 457                 plpar_hcall_norets(H_SET_PARTITION_TABLE, 0);
 458                 kfree(pseries_partition_tb);
 459                 pseries_partition_tb = NULL;
 460         }
 461 }
 462
 463 static void kvmhv_flush_lpid(unsigned int lpid)
 464 {
 465         long rc;
 466
 467         if (!kvmhv_on_pseries()) {
 468                 radix__flush_all_lpid(lpid);
 469                 return;
 470         }
 471
 472         if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE))
 473                 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
 474                                         lpid, TLBIEL_INVAL_SET_LPID);
 475         else
 476                 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
 477                                             H_RPTI_TYPE_NESTED |
 478                                             H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
 479                                             H_RPTI_TYPE_PAT,
 480                                             H_RPTI_PAGE_ALL, 0, -1UL);
 481         if (rc)
 482                 pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
 483 }
 484
 485 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1)
 486 {
 487         if (!kvmhv_on_pseries()) {
 488                 mmu_partition_table_set_entry(lpid, dw0, dw1, true);
 489                 return;
 490         }
 491
 492         pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
 493         pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
 494         /* L0 will do the necessary barriers */
 495         kvmhv_flush_lpid(lpid);
 496 }
 497
 498 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp)
 499 {
 500         unsigned long dw0;
 501
 502         dw0 = PATB_HR | radix__get_tree_size() |
 503                 __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE;
 504         kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table);
 505 }
 506
 507 void kvmhv_vm_nested_init(struct kvm *kvm)
 508 {
 509         kvm->arch.max_nested_lpid = -1;
 510 }
 511
 512 /*
 513  * Handle the H_SET_PARTITION_TABLE hcall.
 514  * r4 = guest real address of partition table + log_2(size) - 12
 515  * (formatted as for the PTCR).
 516  */
 517 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu)
 518 {
 519         struct kvm *kvm = vcpu->kvm;
 520         unsigned long ptcr = kvmppc_get_gpr(vcpu, 4);
 521         int srcu_idx;
 522         long ret = H_SUCCESS;
 523
 524         srcu_idx = srcu_read_lock(&kvm->srcu);
 525         /*
 526          * Limit the partition table to 4096 entries (because that's what
 527          * hardware supports), and check the base address.
 528          */
 529         if ((ptcr & PRTS_MASK) > 12 - 8 ||
 530             !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT))
 531                 ret = H_PARAMETER;
 532         srcu_read_unlock(&kvm->srcu, srcu_idx);
 533         if (ret == H_SUCCESS)
 534                 kvm->arch.l1_ptcr = ptcr;
 535         return ret;
 536 }
 537
 538 /*
 539  * Handle the H_COPY_TOFROM_GUEST hcall.
 540  * r4 = L1 lpid of nested guest
 541  * r5 = pid
 542  * r6 = eaddr to access
 543  * r7 = to buffer (L1 gpa)
 544  * r8 = from buffer (L1 gpa)
 545  * r9 = n bytes to copy
 546  */
 547 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu)
 548 {
 549         struct kvm_nested_guest *gp;
 550         int l1_lpid = kvmppc_get_gpr(vcpu, 4);
 551         int pid = kvmppc_get_gpr(vcpu, 5);
 552         gva_t eaddr = kvmppc_get_gpr(vcpu, 6);
 553         gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7);
 554         gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8);
 555         void *buf;
 556         unsigned long n = kvmppc_get_gpr(vcpu, 9);
 557         bool is_load = !!gp_to;
 558         long rc;
 559
 560         if (gp_to && gp_from) /* One must be NULL to determine the direction */
 561                 return H_PARAMETER;
 562
 563         if (eaddr & (0xFFFUL << 52))
 564                 return H_PARAMETER;
 565
 566         buf = kzalloc(n, GFP_KERNEL);
 567         if (!buf)
 568                 return H_NO_MEM;
 569
 570         gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false);
 571         if (!gp) {
 572                 rc = H_PARAMETER;
 573                 goto out_free;
 574         }
 575
 576         mutex_lock(&gp->tlb_lock);
 577
 578         if (is_load) {
 579                 /* Load from the nested guest into our buffer */
 580                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 581                                                      eaddr, buf, NULL, n);
 582                 if (rc)
 583                         goto not_found;
 584
 585                 /* Write what was loaded into our buffer back to the L1 guest */
 586                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 587                 rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n);
 588                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 589                 if (rc)
 590                         goto not_found;
 591         } else {
 592                 /* Load the data to be stored from the L1 guest into our buf */
 593                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 594                 rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n);
 595                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 596                 if (rc)
 597                         goto not_found;
 598
 599                 /* Store from our buffer into the nested guest */
 600                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 601                                                      eaddr, NULL, buf, n);
 602                 if (rc)
 603                         goto not_found;
 604         }
 605
 606 out_unlock:
 607         mutex_unlock(&gp->tlb_lock);
 608         kvmhv_put_nested(gp);
 609 out_free:
 610         kfree(buf);
 611         return rc;
 612 not_found:
 613         rc = H_NOT_FOUND;
 614         goto out_unlock;
 615 }
 616
 617 /*
 618  * Reload the partition table entry for a guest.
 619  * Caller must hold gp->tlb_lock.
 620  */
 621 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp)
 622 {
 623         int ret;
 624         struct patb_entry ptbl_entry;
 625         unsigned long ptbl_addr;
 626         struct kvm *kvm = gp->l1_host;
 627
 628         ret = -EFAULT;
 629         ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4);
 630         if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 8))) {
 631                 int srcu_idx = srcu_read_lock(&kvm->srcu);
 632                 ret = kvm_read_guest(kvm, ptbl_addr,
 633                                      &ptbl_entry, sizeof(ptbl_entry));
 634                 srcu_read_unlock(&kvm->srcu, srcu_idx);
 635         }
 636         if (ret) {
 637                 gp->l1_gr_to_hr = 0;
 638                 gp->process_table = 0;
 639         } else {
 640                 gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0);
 641                 gp->process_table = be64_to_cpu(ptbl_entry.patb1);
 642         }
 643         kvmhv_set_nested_ptbl(gp);
 644 }
 645
 646 static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
 647 {
 648         struct kvm_nested_guest *gp;
 649         long shadow_lpid;
 650
 651         gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 652         if (!gp)
 653                 return NULL;
 654         gp->l1_host = kvm;
 655         gp->l1_lpid = lpid;
 656         mutex_init(&gp->tlb_lock);
 657         gp->shadow_pgtable = pgd_alloc(kvm->mm);
 658         if (!gp->shadow_pgtable)
 659                 goto out_free;
 660         shadow_lpid = kvmppc_alloc_lpid();
 661         if (shadow_lpid < 0)
 662                 goto out_free2;
 663         gp->shadow_lpid = shadow_lpid;
 664         gp->radix = 1;
 665
 666         memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu));
 667
 668         return gp;
 669
 670  out_free2:
 671         pgd_free(kvm->mm, gp->shadow_pgtable);
 672  out_free:
 673         kfree(gp);
 674         return NULL;
 675 }
 676
 677 /*
 678  * Free up any resources allocated for a nested guest.
 679  */
 680 static void kvmhv_release_nested(struct kvm_nested_guest *gp)
 681 {
 682         struct kvm *kvm = gp->l1_host;
 683
 684         if (gp->shadow_pgtable) {
 685                 /*
 686                  * No vcpu is using this struct and no call to
 687                  * kvmhv_get_nested can find this struct,
 688                  * so we don't need to hold kvm->mmu_lock.
 689                  */
 690                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
 691                                           gp->shadow_lpid);
 692                 pgd_free(kvm->mm, gp->shadow_pgtable);
 693         }
 694         kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0);
 695         kvmppc_free_lpid(gp->shadow_lpid);
 696         kfree(gp);
 697 }
 698
 699 static void kvmhv_remove_nested(struct kvm_nested_guest *gp)
 700 {
 701         struct kvm *kvm = gp->l1_host;
 702         int lpid = gp->l1_lpid;
 703         long ref;
 704
 705         spin_lock(&kvm->mmu_lock);
 706         if (gp == kvm->arch.nested_guests[lpid]) {
 707                 kvm->arch.nested_guests[lpid] = NULL;
 708                 if (lpid == kvm->arch.max_nested_lpid) {
 709                         while (--lpid >= 0 && !kvm->arch.nested_guests[lpid])
 710                                 ;
 711                         kvm->arch.max_nested_lpid = lpid;
 712                 }
 713                 --gp->refcnt;
 714         }
 715         ref = gp->refcnt;
 716         spin_unlock(&kvm->mmu_lock);
 717         if (ref == 0)
 718                 kvmhv_release_nested(gp);
 719 }
 720
 721 /*
 722  * Free up all nested resources allocated for this guest.
 723  * This is called with no vcpus of the guest running, when
 724  * switching the guest to HPT mode or when destroying the
 725  * guest.
 726  */
 727 void kvmhv_release_all_nested(struct kvm *kvm)
 728 {
 729         int i;
 730         struct kvm_nested_guest *gp;
 731         struct kvm_nested_guest *freelist = NULL;
 732         struct kvm_memory_slot *memslot;
 733         int srcu_idx;
 734
 735         spin_lock(&kvm->mmu_lock);
 736         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
 737                 gp = kvm->arch.nested_guests[i];
 738                 if (!gp)
 739                         continue;
 740                 kvm->arch.nested_guests[i] = NULL;
 741                 if (--gp->refcnt == 0) {
 742                         gp->next = freelist;
 743                         freelist = gp;
 744                 }
 745         }
 746         kvm->arch.max_nested_lpid = -1;
 747         spin_unlock(&kvm->mmu_lock);
 748         while ((gp = freelist) != NULL) {
 749                 freelist = gp->next;
 750                 kvmhv_release_nested(gp);
 751         }
 752
 753         srcu_idx = srcu_read_lock(&kvm->srcu);
 754         kvm_for_each_memslot(memslot, kvm_memslots(kvm))
 755                 kvmhv_free_memslot_nest_rmap(memslot);
 756         srcu_read_unlock(&kvm->srcu, srcu_idx);
 757 }
 758
 759 /* caller must hold gp->tlb_lock */
 760 static void kvmhv_flush_nested(struct kvm_nested_guest *gp)
 761 {
 762         struct kvm *kvm = gp->l1_host;
 763
 764         spin_lock(&kvm->mmu_lock);
 765         kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid);
 766         spin_unlock(&kvm->mmu_lock);
 767         kvmhv_flush_lpid(gp->shadow_lpid);
 768         kvmhv_update_ptbl_cache(gp);
 769         if (gp->l1_gr_to_hr == 0)
 770                 kvmhv_remove_nested(gp);
 771 }
 772
 773 struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
 774                                           bool create)
 775 {
 776         struct kvm_nested_guest *gp, *newgp;
 777
 778         if (l1_lpid >= KVM_MAX_NESTED_GUESTS ||
 779             l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4)))
 780                 return NULL;
 781
 782         spin_lock(&kvm->mmu_lock);
 783         gp = kvm->arch.nested_guests[l1_lpid];
 784         if (gp)
 785                 ++gp->refcnt;
 786         spin_unlock(&kvm->mmu_lock);
 787
 788         if (gp || !create)
 789                 return gp;
 790
 791         newgp = kvmhv_alloc_nested(kvm, l1_lpid);
 792         if (!newgp)
 793                 return NULL;
 794         spin_lock(&kvm->mmu_lock);
 795         if (kvm->arch.nested_guests[l1_lpid]) {
 796                 /* someone else beat us to it */
 797                 gp = kvm->arch.nested_guests[l1_lpid];
 798         } else {
 799                 kvm->arch.nested_guests[l1_lpid] = newgp;
 800                 ++newgp->refcnt;
 801                 gp = newgp;
 802                 newgp = NULL;
 803                 if (l1_lpid > kvm->arch.max_nested_lpid)
 804                         kvm->arch.max_nested_lpid = l1_lpid;
 805         }
 806         ++gp->refcnt;
 807         spin_unlock(&kvm->mmu_lock);
 808
 809         if (newgp)
 810                 kvmhv_release_nested(newgp);
 811
 812         return gp;
 813 }
 814
 815 void kvmhv_put_nested(struct kvm_nested_guest *gp)
 816 {
 817         struct kvm *kvm = gp->l1_host;
 818         long ref;
 819
 820         spin_lock(&kvm->mmu_lock);
 821         ref = --gp->refcnt;
 822         spin_unlock(&kvm->mmu_lock);
 823         if (ref == 0)
 824                 kvmhv_release_nested(gp);
 825 }
 826
 827 static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid)
 828 {
 829         if (lpid > kvm->arch.max_nested_lpid)
 830                 return NULL;
 831         return kvm->arch.nested_guests[lpid];
 832 }
 833
 834 pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid,
 835                                  unsigned long ea, unsigned *hshift)
 836 {
 837         struct kvm_nested_guest *gp;
 838         pte_t *pte;
 839
 840         gp = kvmhv_find_nested(kvm, lpid);
 841         if (!gp)
 842                 return NULL;
 843
 844         VM_WARN(!spin_is_locked(&kvm->mmu_lock),
 845                 "%s called with kvm mmu_lock not held \n", __func__);
 846         pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift);
 847
 848         return pte;
 849 }
 850
 851 static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2)
 852 {
 853         return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK |
 854                                        RMAP_NESTED_GPA_MASK));
 855 }
 856
 857 void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
 858                             struct rmap_nested **n_rmap)
 859 {
 860         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 861         struct rmap_nested *cursor;
 862         u64 rmap, new_rmap = (*n_rmap)->rmap;
 863
 864         /* Are there any existing entries? */
 865         if (!(*rmapp)) {
 866                 /* No -> use the rmap as a single entry */
 867                 *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY;
 868                 return;
 869         }
 870
 871         /* Do any entries match what we're trying to insert? */
 872         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 873                 if (kvmhv_n_rmap_is_equal(rmap, new_rmap))
 874                         return;
 875         }
 876
 877         /* Do we need to create a list or just add the new entry? */
 878         rmap = *rmapp;
 879         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 880                 *rmapp = 0UL;
 881         llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp);
 882         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 883                 (*n_rmap)->list.next = (struct llist_node *) rmap;
 884
 885         /* Set NULL so not freed by caller */
 886         *n_rmap = NULL;
 887 }
 888
 889 static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap,
 890                                       unsigned long clr, unsigned long set,
 891                                       unsigned long hpa, unsigned long mask)
 892 {
 893         unsigned long gpa;
 894         unsigned int shift, lpid;
 895         pte_t *ptep;
 896
 897         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 898         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 899
 900         /* Find the pte */
 901         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 902         /*
 903          * If the pte is present and the pfn is still the same, update the pte.
 904          * If the pfn has changed then this is a stale rmap entry, the nested
 905          * gpa actually points somewhere else now, and there is nothing to do.
 906          * XXX A future optimisation would be to remove the rmap entry here.
 907          */
 908         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) {
 909                 __radix_pte_update(ptep, clr, set);
 910                 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
 911         }
 912 }
 913
 914 /*
 915  * For a given list of rmap entries, update the rc bits in all ptes in shadow
 916  * page tables for nested guests which are referenced by the rmap list.
 917  */
 918 void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp,
 919                                     unsigned long clr, unsigned long set,
 920                                     unsigned long hpa, unsigned long nbytes)
 921 {
 922         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 923         struct rmap_nested *cursor;
 924         unsigned long rmap, mask;
 925
 926         if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED))
 927                 return;
 928
 929         mask = PTE_RPN_MASK & ~(nbytes - 1);
 930         hpa &= mask;
 931
 932         for_each_nest_rmap_safe(cursor, entry, &rmap)
 933                 kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask);
 934 }
 935
 936 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
 937                                    unsigned long hpa, unsigned long mask)
 938 {
 939         struct kvm_nested_guest *gp;
 940         unsigned long gpa;
 941         unsigned int shift, lpid;
 942         pte_t *ptep;
 943
 944         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 945         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 946         gp = kvmhv_find_nested(kvm, lpid);
 947         if (!gp)
 948                 return;
 949
 950         /* Find and invalidate the pte */
 951         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 952         /* Don't spuriously invalidate ptes if the pfn has changed */
 953         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa))
 954                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
 955 }
 956
 957 static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
 958                                         unsigned long hpa, unsigned long mask)
 959 {
 960         struct llist_node *entry = llist_del_all((struct llist_head *) rmapp);
 961         struct rmap_nested *cursor;
 962         unsigned long rmap;
 963
 964         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 965                 kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask);
 966                 kfree(cursor);
 967         }
 968 }
 969
 970 /* called with kvm->mmu_lock held */
 971 void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
 972                                   const struct kvm_memory_slot *memslot,
 973                                   unsigned long gpa, unsigned long hpa,
 974                                   unsigned long nbytes)
 975 {
 976         unsigned long gfn, end_gfn;
 977         unsigned long addr_mask;
 978
 979         if (!memslot)
 980                 return;
 981         gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn;
 982         end_gfn = gfn + (nbytes >> PAGE_SHIFT);
 983
 984         addr_mask = PTE_RPN_MASK & ~(nbytes - 1);
 985         hpa &= addr_mask;
 986
 987         for (; gfn < end_gfn; gfn++) {
 988                 unsigned long *rmap = &memslot->arch.rmap[gfn];
 989                 kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask);
 990         }
 991 }
 992
 993 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free)
 994 {
 995         unsigned long page;
 996
 997         for (page = 0; page < free->npages; page++) {
 998                 unsigned long rmap, *rmapp = &free->arch.rmap[page];
 999                 struct rmap_nested *cursor;
1000                 struct llist_node *entry;
1001
1002                 entry = llist_del_all((struct llist_head *) rmapp);
1003                 for_each_nest_rmap_safe(cursor, entry, &rmap)
1004                         kfree(cursor);
1005         }
1006 }
1007
1008 static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu,
1009                                         struct kvm_nested_guest *gp,
1010                                         long gpa, int *shift_ret)
1011 {
1012         struct kvm *kvm = vcpu->kvm;
1013         bool ret = false;
1014         pte_t *ptep;
1015         int shift;
1016
1017         spin_lock(&kvm->mmu_lock);
1018         ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift);
1019         if (!shift)
1020                 shift = PAGE_SHIFT;
1021         if (ptep && pte_present(*ptep)) {
1022                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
1023                 ret = true;
1024         }
1025         spin_unlock(&kvm->mmu_lock);
1026
1027         if (shift_ret)
1028                 *shift_ret = shift;
1029         return ret;
1030 }
1031
1032 static inline int get_ric(unsigned int instr)
1033 {
1034         return (instr >> 18) & 0x3;
1035 }
1036
1037 static inline int get_prs(unsigned int instr)
1038 {
1039         return (instr >> 17) & 0x1;
1040 }
1041
1042 static inline int get_r(unsigned int instr)
1043 {
1044         return (instr >> 16) & 0x1;
1045 }
1046
1047 static inline int get_lpid(unsigned long r_val)
1048 {
1049         return r_val & 0xffffffff;
1050 }
1051
1052 static inline int get_is(unsigned long r_val)
1053 {
1054         return (r_val >> 10) & 0x3;
1055 }
1056
1057 static inline int get_ap(unsigned long r_val)
1058 {
1059         return (r_val >> 5) & 0x7;
1060 }
1061
1062 static inline long get_epn(unsigned long r_val)
1063 {
1064         return r_val >> 12;
1065 }
1066
1067 static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid,
1068                                         int ap, long epn)
1069 {
1070         struct kvm *kvm = vcpu->kvm;
1071         struct kvm_nested_guest *gp;
1072         long npages;
1073         int shift, shadow_shift;
1074         unsigned long addr;
1075
1076         shift = ap_to_shift(ap);
1077         addr = epn << 12;
1078         if (shift < 0)
1079                 /* Invalid ap encoding */
1080                 return -EINVAL;
1081
1082         addr &= ~((1UL << shift) - 1);
1083         npages = 1UL << (shift - PAGE_SHIFT);
1084
1085         gp = kvmhv_get_nested(kvm, lpid, false);
1086         if (!gp) /* No such guest -> nothing to do */
1087                 return 0;
1088         mutex_lock(&gp->tlb_lock);
1089
1090         /* There may be more than one host page backing this single guest pte */
1091         do {
1092                 kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift);
1093
1094                 npages -= 1UL << (shadow_shift - PAGE_SHIFT);
1095                 addr += 1UL << shadow_shift;
1096         } while (npages > 0);
1097
1098         mutex_unlock(&gp->tlb_lock);
1099         kvmhv_put_nested(gp);
1100         return 0;
1101 }
1102
1103 static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu,
1104                                      struct kvm_nested_guest *gp, int ric)
1105 {
1106         struct kvm *kvm = vcpu->kvm;
1107
1108         mutex_lock(&gp->tlb_lock);
1109         switch (ric) {
1110         case 0:
1111                 /* Invalidate TLB */
1112                 spin_lock(&kvm->mmu_lock);
1113                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
1114                                           gp->shadow_lpid);
1115                 kvmhv_flush_lpid(gp->shadow_lpid);
1116                 spin_unlock(&kvm->mmu_lock);
1117                 break;
1118         case 1:
1119                 /*
1120                  * Invalidate PWC
1121                  * We don't cache this -> nothing to do
1122                  */
1123                 break;
1124         case 2:
1125                 /* Invalidate TLB, PWC and caching of partition table entries */
1126                 kvmhv_flush_nested(gp);
1127                 break;
1128         default:
1129                 break;
1130         }
1131         mutex_unlock(&gp->tlb_lock);
1132 }
1133
1134 static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric)
1135 {
1136         struct kvm *kvm = vcpu->kvm;
1137         struct kvm_nested_guest *gp;
1138         int i;
1139
1140         spin_lock(&kvm->mmu_lock);
1141         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
1142                 gp = kvm->arch.nested_guests[i];
1143                 if (gp) {
1144                         spin_unlock(&kvm->mmu_lock);
1145                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1146                         spin_lock(&kvm->mmu_lock);
1147                 }
1148         }
1149         spin_unlock(&kvm->mmu_lock);
1150 }
1151
1152 static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr,
1153                                     unsigned long rsval, unsigned long rbval)
1154 {
1155         struct kvm *kvm = vcpu->kvm;
1156         struct kvm_nested_guest *gp;
1157         int r, ric, prs, is, ap;
1158         int lpid;
1159         long epn;
1160         int ret = 0;
1161
1162         ric = get_ric(instr);
1163         prs = get_prs(instr);
1164         r = get_r(instr);
1165         lpid = get_lpid(rsval);
1166         is = get_is(rbval);
1167
1168         /*
1169          * These cases are invalid and are not handled:
1170          * r   != 1 -> Only radix supported
1171          * prs == 1 -> Not HV privileged
1172          * ric == 3 -> No cluster bombs for radix
1173          * is  == 1 -> Partition scoped translations not associated with pid
1174          * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA
1175          */
1176         if ((!r) || (prs) || (ric == 3) || (is == 1) ||
1177             ((!is) && (ric == 1 || ric == 2)))
1178                 return -EINVAL;
1179
1180         switch (is) {
1181         case 0:
1182                 /*
1183                  * We know ric == 0
1184                  * Invalidate TLB for a given target address
1185                  */
1186                 epn = get_epn(rbval);
1187                 ap = get_ap(rbval);
1188                 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn);
1189                 break;
1190         case 2:
1191                 /* Invalidate matching LPID */
1192                 gp = kvmhv_get_nested(kvm, lpid, false);
1193                 if (gp) {
1194                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1195                         kvmhv_put_nested(gp);
1196                 }
1197                 break;
1198         case 3:
1199                 /* Invalidate ALL LPIDs */
1200                 kvmhv_emulate_tlbie_all_lpid(vcpu, ric);
1201                 break;
1202         default:
1203                 ret = -EINVAL;
1204                 break;
1205         }
1206
1207         return ret;
1208 }
1209
1210 /*
1211  * This handles the H_TLB_INVALIDATE hcall.
1212  * Parameters are (r4) tlbie instruction code, (r5) rS contents,
1213  * (r6) rB contents.
1214  */
1215 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
1216 {
1217         int ret;
1218
1219         ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4),
1220                         kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6));
1221         if (ret)
1222                 return H_PARAMETER;
1223         return H_SUCCESS;
1224 }
1225
1226 static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
1227                                          unsigned long lpid, unsigned long ric)
1228 {
1229         struct kvm *kvm = vcpu->kvm;
1230         struct kvm_nested_guest *gp;
1231
1232         gp = kvmhv_get_nested(kvm, lpid, false);
1233         if (gp) {
1234                 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1235                 kvmhv_put_nested(gp);
1236         }
1237         return H_SUCCESS;
1238 }
1239
1240 /*
1241  * Number of pages above which we invalidate the entire LPID rather than
1242  * flush individual pages.
1243  */
1244 static unsigned long tlb_range_flush_page_ceiling __read_mostly = 33;
1245
1246 static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
1247                                          unsigned long lpid,
1248                                          unsigned long pg_sizes,
1249                                          unsigned long start,
1250                                          unsigned long end)
1251 {
1252         int ret = H_P4;
1253         unsigned long addr, nr_pages;
1254         struct mmu_psize_def *def;
1255         unsigned long psize, ap, page_size;
1256         bool flush_lpid;
1257
1258         for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
1259                 def = &mmu_psize_defs[psize];
1260                 if (!(pg_sizes & def->h_rpt_pgsize))
1261                         continue;
1262
1263                 nr_pages = (end - start) >> def->shift;
1264                 flush_lpid = nr_pages > tlb_range_flush_page_ceiling;
1265                 if (flush_lpid)
1266                         return do_tlb_invalidate_nested_all(vcpu, lpid,
1267                                                         RIC_FLUSH_TLB);
1268                 addr = start;
1269                 ap = mmu_get_ap(psize);
1270                 page_size = 1UL << def->shift;
1271                 do {
1272                         ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
1273                                                    get_epn(addr));
1274                         if (ret)
1275                                 return H_P4;
1276                         addr += page_size;
1277                 } while (addr < end);
1278         }
1279         return ret;
1280 }
1281
1282 /*
1283  * Performs partition-scoped invalidations for nested guests
1284  * as part of H_RPT_INVALIDATE hcall.
1285  */
1286 long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
1287                              unsigned long type, unsigned long pg_sizes,
1288                              unsigned long start, unsigned long end)
1289 {
1290         /*
1291          * If L2 lpid isn't valid, we need to return H_PARAMETER.
1292          *
1293          * However, nested KVM issues a L2 lpid flush call when creating
1294          * partition table entries for L2. This happens even before the
1295          * corresponding shadow lpid is created in HV which happens in
1296          * H_ENTER_NESTED call. Since we can't differentiate this case from
1297          * the invalid case, we ignore such flush requests and return success.
1298          */
1299         if (!kvmhv_find_nested(vcpu->kvm, lpid))
1300                 return H_SUCCESS;
1301
1302         /*
1303          * A flush all request can be handled by a full lpid flush only.
1304          */
1305         if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
1306                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
1307
1308         /*
1309          * We don't need to handle a PWC flush like process table here,
1310          * because intermediate partition scoped table in nested guest doesn't
1311          * really have PWC. Only level we have PWC is in L0 and for nested
1312          * invalidate at L0 we always do kvm_flush_lpid() which does
1313          * radix__flush_all_lpid(). For range invalidate at any level, we
1314          * are not removing the higher level page tables and hence there is
1315          * no PWC invalidate needed.
1316          *
1317          * if (type & H_RPTI_TYPE_PWC) {
1318          *      ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
1319          *      if (ret)
1320          *              return H_P4;
1321          * }
1322          */
1323
1324         if (start == 0 && end == -1)
1325                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
1326
1327         if (type & H_RPTI_TYPE_TLB)
1328                 return do_tlb_invalidate_nested_tlb(vcpu, lpid, pg_sizes,
1329                                                     start, end);
1330         return H_SUCCESS;
1331 }
1332
1333 /* Used to convert a nested guest real address to a L1 guest real address */
1334 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
1335                                        struct kvm_nested_guest *gp,
1336                                        unsigned long n_gpa, unsigned long dsisr,
1337                                        struct kvmppc_pte *gpte_p)
1338 {
1339         u64 fault_addr, flags = dsisr & DSISR_ISSTORE;
1340         int ret;
1341
1342         ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr,
1343                                          &fault_addr);
1344
1345         if (ret) {
1346                 /* We didn't find a pte */
1347                 if (ret == -EINVAL) {
1348                         /* Unsupported mmu config */
1349                         flags |= DSISR_UNSUPP_MMU;
1350                 } else if (ret == -ENOENT) {
1351                         /* No translation found */
1352                         flags |= DSISR_NOHPTE;
1353                 } else if (ret == -EFAULT) {
1354                         /* Couldn't access L1 real address */
1355                         flags |= DSISR_PRTABLE_FAULT;
1356                         vcpu->arch.fault_gpa = fault_addr;
1357                 } else {
1358                         /* Unknown error */
1359                         return ret;
1360                 }
1361                 goto forward_to_l1;
1362         } else {
1363                 /* We found a pte -> check permissions */
1364                 if (dsisr & DSISR_ISSTORE) {
1365                         /* Can we write? */
1366                         if (!gpte_p->may_write) {
1367                                 flags |= DSISR_PROTFAULT;
1368                                 goto forward_to_l1;
1369                         }
1370                 } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1371                         /* Can we execute? */
1372                         if (!gpte_p->may_execute) {
1373                                 flags |= SRR1_ISI_N_G_OR_CIP;
1374                                 goto forward_to_l1;
1375                         }
1376                 } else {
1377                         /* Can we read? */
1378                         if (!gpte_p->may_read && !gpte_p->may_write) {
1379                                 flags |= DSISR_PROTFAULT;
1380                                 goto forward_to_l1;
1381                         }
1382                 }
1383         }
1384
1385         return 0;
1386
1387 forward_to_l1:
1388         vcpu->arch.fault_dsisr = flags;
1389         if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1390                 vcpu->arch.shregs.msr &= SRR1_MSR_BITS;
1391                 vcpu->arch.shregs.msr |= flags;
1392         }
1393         return RESUME_HOST;
1394 }
1395
1396 static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
1397                                        struct kvm_nested_guest *gp,
1398                                        unsigned long n_gpa,
1399                                        struct kvmppc_pte gpte,
1400                                        unsigned long dsisr)
1401 {
1402         struct kvm *kvm = vcpu->kvm;
1403         bool writing = !!(dsisr & DSISR_ISSTORE);
1404         u64 pgflags;
1405         long ret;
1406
1407         /* Are the rc bits set in the L1 partition scoped pte? */
1408         pgflags = _PAGE_ACCESSED;
1409         if (writing)
1410                 pgflags |= _PAGE_DIRTY;
1411         if (pgflags & ~gpte.rc)
1412                 return RESUME_HOST;
1413
1414         spin_lock(&kvm->mmu_lock);
1415         /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
1416         ret = kvmppc_hv_handle_set_rc(kvm, false, writing,
1417                                       gpte.raddr, kvm->arch.lpid);
1418         if (!ret) {
1419                 ret = -EINVAL;
1420                 goto out_unlock;
1421         }
1422
1423         /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
1424         ret = kvmppc_hv_handle_set_rc(kvm, true, writing,
1425                                       n_gpa, gp->l1_lpid);
1426         if (!ret)
1427                 ret = -EINVAL;
1428         else
1429                 ret = 0;
1430
1431 out_unlock:
1432         spin_unlock(&kvm->mmu_lock);
1433         return ret;
1434 }
1435
1436 static inline int kvmppc_radix_level_to_shift(int level)
1437 {
1438         switch (level) {
1439         case 2:
1440                 return PUD_SHIFT;
1441         case 1:
1442                 return PMD_SHIFT;
1443         default:
1444                 return PAGE_SHIFT;
1445         }
1446 }
1447
1448 static inline int kvmppc_radix_shift_to_level(int shift)
1449 {
1450         if (shift == PUD_SHIFT)
1451                 return 2;
1452         if (shift == PMD_SHIFT)
1453                 return 1;
1454         if (shift == PAGE_SHIFT)
1455                 return 0;
1456         WARN_ON_ONCE(1);
1457         return 0;
1458 }
1459
1460 /* called with gp->tlb_lock held */
1461 static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
1462                                           struct kvm_nested_guest *gp)
1463 {
1464         struct kvm *kvm = vcpu->kvm;
1465         struct kvm_memory_slot *memslot;
1466         struct rmap_nested *n_rmap;
1467         struct kvmppc_pte gpte;
1468         pte_t pte, *pte_p;
1469         unsigned long mmu_seq;
1470         unsigned long dsisr = vcpu->arch.fault_dsisr;
1471         unsigned long ea = vcpu->arch.fault_dar;
1472         unsigned long *rmapp;
1473         unsigned long n_gpa, gpa, gfn, perm = 0UL;
1474         unsigned int shift, l1_shift, level;
1475         bool writing = !!(dsisr & DSISR_ISSTORE);
1476         bool kvm_ro = false;
1477         long int ret;
1478
1479         if (!gp->l1_gr_to_hr) {
1480                 kvmhv_update_ptbl_cache(gp);
1481                 if (!gp->l1_gr_to_hr)
1482                         return RESUME_HOST;
1483         }
1484
1485         /* Convert the nested guest real address into a L1 guest real address */
1486
1487         n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL;
1488         if (!(dsisr & DSISR_PRTABLE_FAULT))
1489                 n_gpa |= ea & 0xFFF;
1490         ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte);
1491
1492         /*
1493          * If the hardware found a translation but we don't now have a usable
1494          * translation in the l1 partition-scoped tree, remove the shadow pte
1495          * and let the guest retry.
1496          */
1497         if (ret == RESUME_HOST &&
1498             (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G |
1499                       DSISR_BAD_COPYPASTE)))
1500                 goto inval;
1501         if (ret)
1502                 return ret;
1503
1504         /* Failed to set the reference/change bits */
1505         if (dsisr & DSISR_SET_RC) {
1506                 ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr);
1507                 if (ret == RESUME_HOST)
1508                         return ret;
1509                 if (ret)
1510                         goto inval;
1511                 dsisr &= ~DSISR_SET_RC;
1512                 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
1513                                DSISR_PROTFAULT)))
1514                         return RESUME_GUEST;
1515         }
1516
1517         /*
1518          * We took an HISI or HDSI while we were running a nested guest which
1519          * means we have no partition scoped translation for that. This means
1520          * we need to insert a pte for the mapping into our shadow_pgtable.
1521          */
1522
1523         l1_shift = gpte.page_shift;
1524         if (l1_shift < PAGE_SHIFT) {
1525                 /* We don't support l1 using a page size smaller than our own */
1526                 pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n",
1527                         l1_shift, PAGE_SHIFT);
1528                 return -EINVAL;
1529         }
1530         gpa = gpte.raddr;
1531         gfn = gpa >> PAGE_SHIFT;
1532
1533         /* 1. Get the corresponding host memslot */
1534
1535         memslot = gfn_to_memslot(kvm, gfn);
1536         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
1537                 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) {
1538                         /* unusual error -> reflect to the guest as a DSI */
1539                         kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
1540                         return RESUME_GUEST;
1541                 }
1542
1543                 /* passthrough of emulated MMIO case */
1544                 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing);
1545         }
1546         if (memslot->flags & KVM_MEM_READONLY) {
1547                 if (writing) {
1548                         /* Give the guest a DSI */
1549                         kvmppc_core_queue_data_storage(vcpu, ea,
1550                                         DSISR_ISSTORE | DSISR_PROTFAULT);
1551                         return RESUME_GUEST;
1552                 }
1553                 kvm_ro = true;
1554         }
1555
1556         /* 2. Find the host pte for this L1 guest real address */
1557
1558         /* Used to check for invalidations in progress */
1559         mmu_seq = kvm->mmu_notifier_seq;
1560         smp_rmb();
1561
1562         /* See if can find translation in our partition scoped tables for L1 */
1563         pte = __pte(0);
1564         spin_lock(&kvm->mmu_lock);
1565         pte_p = find_kvm_secondary_pte(kvm, gpa, &shift);
1566         if (!shift)
1567                 shift = PAGE_SHIFT;
1568         if (pte_p)
1569                 pte = *pte_p;
1570         spin_unlock(&kvm->mmu_lock);
1571
1572         if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) {
1573                 /* No suitable pte found -> try to insert a mapping */
1574                 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot,
1575                                         writing, kvm_ro, &pte, &level);
1576                 if (ret == -EAGAIN)
1577                         return RESUME_GUEST;
1578                 else if (ret)
1579                         return ret;
1580                 shift = kvmppc_radix_level_to_shift(level);
1581         }
1582         /* Align gfn to the start of the page */
1583         gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT;
1584
1585         /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */
1586
1587         /* The permissions is the combination of the host and l1 guest ptes */
1588         perm |= gpte.may_read ? 0UL : _PAGE_READ;
1589         perm |= gpte.may_write ? 0UL : _PAGE_WRITE;
1590         perm |= gpte.may_execute ? 0UL : _PAGE_EXEC;
1591         /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */
1592         perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED;
1593         perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY;
1594         pte = __pte(pte_val(pte) & ~perm);
1595
1596         /* What size pte can we insert? */
1597         if (shift > l1_shift) {
1598                 u64 mask;
1599                 unsigned int actual_shift = PAGE_SHIFT;
1600                 if (PMD_SHIFT < l1_shift)
1601                         actual_shift = PMD_SHIFT;
1602                 mask = (1UL << shift) - (1UL << actual_shift);
1603                 pte = __pte(pte_val(pte) | (gpa & mask));
1604                 shift = actual_shift;
1605         }
1606         level = kvmppc_radix_shift_to_level(shift);
1607         n_gpa &= ~((1UL << shift) - 1);
1608
1609         /* 4. Insert the pte into our shadow_pgtable */
1610
1611         n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL);
1612         if (!n_rmap)
1613                 return RESUME_GUEST; /* Let the guest try again */
1614         n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) |
1615                 (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT);
1616         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1617         ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level,
1618                                 mmu_seq, gp->shadow_lpid, rmapp, &n_rmap);
1619         kfree(n_rmap);
1620         if (ret == -EAGAIN)
1621                 ret = RESUME_GUEST;     /* Let the guest try again */
1622
1623         return ret;
1624
1625  inval:
1626         kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL);
1627         return RESUME_GUEST;
1628 }
1629
1630 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu)
1631 {
1632         struct kvm_nested_guest *gp = vcpu->arch.nested;
1633         long int ret;
1634
1635         mutex_lock(&gp->tlb_lock);
1636         ret = __kvmhv_nested_page_fault(vcpu, gp);
1637         mutex_unlock(&gp->tlb_lock);
1638         return ret;
1639 }
1640
1641 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid)
1642 {
1643         int ret = -1;
1644
1645         spin_lock(&kvm->mmu_lock);
1646         while (++lpid <= kvm->arch.max_nested_lpid) {
1647                 if (kvm->arch.nested_guests[lpid]) {
1648                         ret = lpid;
1649                         break;
1650                 }
1651         }
1652         spin_unlock(&kvm->mmu_lock);
1653         return ret;
1654 }