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         if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr))
 306                 return H_BAD_MODE;
 307
 308         /* copy parameters in */
 309         hv_ptr = kvmppc_get_gpr(vcpu, 4);
 310         regs_ptr = kvmppc_get_gpr(vcpu, 5);
 311         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 312         err = kvmhv_read_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 313                                               hv_ptr, regs_ptr);
 314         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 315         if (err)
 316                 return H_PARAMETER;
 317
 318         if (kvmppc_need_byteswap(vcpu))
 319                 byteswap_hv_regs(&l2_hv);
 320         if (l2_hv.version > HV_GUEST_STATE_VERSION)
 321                 return H_P2;
 322
 323         if (kvmppc_need_byteswap(vcpu))
 324                 byteswap_pt_regs(&l2_regs);
 325         if (l2_hv.vcpu_token >= NR_CPUS)
 326                 return H_PARAMETER;
 327
 328         /*
 329          * L1 must have set up a suspended state to enter the L2 in a
 330          * transactional state, and only in that case. These have to be
 331          * filtered out here to prevent causing a TM Bad Thing in the
 332          * host HRFID. We could synthesize a TM Bad Thing back to the L1
 333          * here but there doesn't seem like much point.
 334          */
 335         if (MSR_TM_SUSPENDED(vcpu->arch.shregs.msr)) {
 336                 if (!MSR_TM_ACTIVE(l2_regs.msr))
 337                         return H_BAD_MODE;
 338         } else {
 339                 if (l2_regs.msr & MSR_TS_MASK)
 340                         return H_BAD_MODE;
 341                 if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_TS_MASK))
 342                         return H_BAD_MODE;
 343         }
 344
 345         /* translate lpid */
 346         l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true);
 347         if (!l2)
 348                 return H_PARAMETER;
 349         if (!l2->l1_gr_to_hr) {
 350                 mutex_lock(&l2->tlb_lock);
 351                 kvmhv_update_ptbl_cache(l2);
 352                 mutex_unlock(&l2->tlb_lock);
 353         }
 354
 355         /* save l1 values of things */
 356         vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
 357         saved_l1_regs = vcpu->arch.regs;
 358         kvmhv_save_hv_regs(vcpu, &saved_l1_hv);
 359
 360         /* convert TB values/offsets to host (L0) values */
 361         hdec_exp = l2_hv.hdec_expiry - vc->tb_offset;
 362         vc->tb_offset += l2_hv.tb_offset;
 363
 364         /* set L1 state to L2 state */
 365         vcpu->arch.nested = l2;
 366         vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token;
 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         sanitise_hv_regs(vcpu, &l2_hv);
 373         restore_hv_regs(vcpu, &l2_hv);
 374
 375         vcpu->arch.ret = RESUME_GUEST;
 376         vcpu->arch.trap = 0;
 377         do {
 378                 if (mftb() >= hdec_exp) {
 379                         vcpu->arch.trap = BOOK3S_INTERRUPT_HV_DECREMENTER;
 380                         r = RESUME_HOST;
 381                         break;
 382                 }
 383                 r = kvmhv_run_single_vcpu(vcpu, hdec_exp, l2_hv.lpcr);
 384         } while (is_kvmppc_resume_guest(r));
 385
 386         /* save L2 state for return */
 387         l2_regs = vcpu->arch.regs;
 388         l2_regs.msr = vcpu->arch.shregs.msr;
 389         delta_purr = vcpu->arch.purr - l2_hv.purr;
 390         delta_spurr = vcpu->arch.spurr - l2_hv.spurr;
 391         delta_ic = vcpu->arch.ic - l2_hv.ic;
 392         delta_vtb = vc->vtb - l2_hv.vtb;
 393         save_hv_return_state(vcpu, vcpu->arch.trap, &l2_hv);
 394
 395         /* restore L1 state */
 396         vcpu->arch.nested = NULL;
 397         vcpu->arch.regs = saved_l1_regs;
 398         vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK;
 399         /* set L1 MSR TS field according to L2 transaction state */
 400         if (l2_regs.msr & MSR_TS_MASK)
 401                 vcpu->arch.shregs.msr |= MSR_TS_S;
 402         vc->tb_offset = saved_l1_hv.tb_offset;
 403         restore_hv_regs(vcpu, &saved_l1_hv);
 404         vcpu->arch.purr += delta_purr;
 405         vcpu->arch.spurr += delta_spurr;
 406         vcpu->arch.ic += delta_ic;
 407         vc->vtb += delta_vtb;
 408
 409         kvmhv_put_nested(l2);
 410
 411         /* copy l2_hv_state and regs back to guest */
 412         if (kvmppc_need_byteswap(vcpu)) {
 413                 byteswap_hv_regs(&l2_hv);
 414                 byteswap_pt_regs(&l2_regs);
 415         }
 416         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 417         err = kvmhv_write_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 418                                                hv_ptr, regs_ptr);
 419         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 420         if (err)
 421                 return H_AUTHORITY;
 422
 423         if (r == -EINTR)
 424                 return H_INTERRUPT;
 425
 426         if (vcpu->mmio_needed) {
 427                 kvmhv_nested_mmio_needed(vcpu, regs_ptr);
 428                 return H_TOO_HARD;
 429         }
 430
 431         return vcpu->arch.trap;
 432 }
 433
 434 long kvmhv_nested_init(void)
 435 {
 436         long int ptb_order;
 437         unsigned long ptcr;
 438         long rc;
 439
 440         if (!kvmhv_on_pseries())
 441                 return 0;
 442         if (!radix_enabled())
 443                 return -ENODEV;
 444
 445         /* find log base 2 of KVMPPC_NR_LPIDS, rounding up */
 446         ptb_order = __ilog2(KVMPPC_NR_LPIDS - 1) + 1;
 447         if (ptb_order < 8)
 448                 ptb_order = 8;
 449         pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order,
 450                                        GFP_KERNEL);
 451         if (!pseries_partition_tb) {
 452                 pr_err("kvm-hv: failed to allocated nested partition table\n");
 453                 return -ENOMEM;
 454         }
 455
 456         ptcr = __pa(pseries_partition_tb) | (ptb_order - 8);
 457         rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr);
 458         if (rc != H_SUCCESS) {
 459                 pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n",
 460                        rc);
 461                 kfree(pseries_partition_tb);
 462                 pseries_partition_tb = NULL;
 463                 return -ENODEV;
 464         }
 465
 466         return 0;
 467 }
 468
 469 void kvmhv_nested_exit(void)
 470 {
 471         /*
 472          * N.B. the kvmhv_on_pseries() test is there because it enables
 473          * the compiler to remove the call to plpar_hcall_norets()
 474          * when CONFIG_PPC_PSERIES=n.
 475          */
 476         if (kvmhv_on_pseries() && pseries_partition_tb) {
 477                 plpar_hcall_norets(H_SET_PARTITION_TABLE, 0);
 478                 kfree(pseries_partition_tb);
 479                 pseries_partition_tb = NULL;
 480         }
 481 }
 482
 483 static void kvmhv_flush_lpid(unsigned int lpid)
 484 {
 485         long rc;
 486
 487         if (!kvmhv_on_pseries()) {
 488                 radix__flush_all_lpid(lpid);
 489                 return;
 490         }
 491
 492         if (!firmware_has_feature(FW_FEATURE_RPT_INVALIDATE))
 493                 rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
 494                                         lpid, TLBIEL_INVAL_SET_LPID);
 495         else
 496                 rc = pseries_rpt_invalidate(lpid, H_RPTI_TARGET_CMMU,
 497                                             H_RPTI_TYPE_NESTED |
 498                                             H_RPTI_TYPE_TLB | H_RPTI_TYPE_PWC |
 499                                             H_RPTI_TYPE_PAT,
 500                                             H_RPTI_PAGE_ALL, 0, -1UL);
 501         if (rc)
 502                 pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
 503 }
 504
 505 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1)
 506 {
 507         if (!kvmhv_on_pseries()) {
 508                 mmu_partition_table_set_entry(lpid, dw0, dw1, true);
 509                 return;
 510         }
 511
 512         pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
 513         pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
 514         /* L0 will do the necessary barriers */
 515         kvmhv_flush_lpid(lpid);
 516 }
 517
 518 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp)
 519 {
 520         unsigned long dw0;
 521
 522         dw0 = PATB_HR | radix__get_tree_size() |
 523                 __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE;
 524         kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table);
 525 }
 526
 527 void kvmhv_vm_nested_init(struct kvm *kvm)
 528 {
 529         kvm->arch.max_nested_lpid = -1;
 530 }
 531
 532 /*
 533  * Handle the H_SET_PARTITION_TABLE hcall.
 534  * r4 = guest real address of partition table + log_2(size) - 12
 535  * (formatted as for the PTCR).
 536  */
 537 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu)
 538 {
 539         struct kvm *kvm = vcpu->kvm;
 540         unsigned long ptcr = kvmppc_get_gpr(vcpu, 4);
 541         int srcu_idx;
 542         long ret = H_SUCCESS;
 543
 544         srcu_idx = srcu_read_lock(&kvm->srcu);
 545         /*
 546          * Limit the partition table to 4096 entries (because that's what
 547          * hardware supports), and check the base address.
 548          */
 549         if ((ptcr & PRTS_MASK) > 12 - 8 ||
 550             !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT))
 551                 ret = H_PARAMETER;
 552         srcu_read_unlock(&kvm->srcu, srcu_idx);
 553         if (ret == H_SUCCESS)
 554                 kvm->arch.l1_ptcr = ptcr;
 555         return ret;
 556 }
 557
 558 /*
 559  * Handle the H_COPY_TOFROM_GUEST hcall.
 560  * r4 = L1 lpid of nested guest
 561  * r5 = pid
 562  * r6 = eaddr to access
 563  * r7 = to buffer (L1 gpa)
 564  * r8 = from buffer (L1 gpa)
 565  * r9 = n bytes to copy
 566  */
 567 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu)
 568 {
 569         struct kvm_nested_guest *gp;
 570         int l1_lpid = kvmppc_get_gpr(vcpu, 4);
 571         int pid = kvmppc_get_gpr(vcpu, 5);
 572         gva_t eaddr = kvmppc_get_gpr(vcpu, 6);
 573         gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7);
 574         gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8);
 575         void *buf;
 576         unsigned long n = kvmppc_get_gpr(vcpu, 9);
 577         bool is_load = !!gp_to;
 578         long rc;
 579
 580         if (gp_to && gp_from) /* One must be NULL to determine the direction */
 581                 return H_PARAMETER;
 582
 583         if (eaddr & (0xFFFUL << 52))
 584                 return H_PARAMETER;
 585
 586         buf = kzalloc(n, GFP_KERNEL);
 587         if (!buf)
 588                 return H_NO_MEM;
 589
 590         gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false);
 591         if (!gp) {
 592                 rc = H_PARAMETER;
 593                 goto out_free;
 594         }
 595
 596         mutex_lock(&gp->tlb_lock);
 597
 598         if (is_load) {
 599                 /* Load from the nested guest into our buffer */
 600                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 601                                                      eaddr, buf, NULL, n);
 602                 if (rc)
 603                         goto not_found;
 604
 605                 /* Write what was loaded into our buffer back to the L1 guest */
 606                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 607                 rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n);
 608                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 609                 if (rc)
 610                         goto not_found;
 611         } else {
 612                 /* Load the data to be stored from the L1 guest into our buf */
 613                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 614                 rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n);
 615                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 616                 if (rc)
 617                         goto not_found;
 618
 619                 /* Store from our buffer into the nested guest */
 620                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 621                                                      eaddr, NULL, buf, n);
 622                 if (rc)
 623                         goto not_found;
 624         }
 625
 626 out_unlock:
 627         mutex_unlock(&gp->tlb_lock);
 628         kvmhv_put_nested(gp);
 629 out_free:
 630         kfree(buf);
 631         return rc;
 632 not_found:
 633         rc = H_NOT_FOUND;
 634         goto out_unlock;
 635 }
 636
 637 /*
 638  * Reload the partition table entry for a guest.
 639  * Caller must hold gp->tlb_lock.
 640  */
 641 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp)
 642 {
 643         int ret;
 644         struct patb_entry ptbl_entry;
 645         unsigned long ptbl_addr;
 646         struct kvm *kvm = gp->l1_host;
 647
 648         ret = -EFAULT;
 649         ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4);
 650         if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 8))) {
 651                 int srcu_idx = srcu_read_lock(&kvm->srcu);
 652                 ret = kvm_read_guest(kvm, ptbl_addr,
 653                                      &ptbl_entry, sizeof(ptbl_entry));
 654                 srcu_read_unlock(&kvm->srcu, srcu_idx);
 655         }
 656         if (ret) {
 657                 gp->l1_gr_to_hr = 0;
 658                 gp->process_table = 0;
 659         } else {
 660                 gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0);
 661                 gp->process_table = be64_to_cpu(ptbl_entry.patb1);
 662         }
 663         kvmhv_set_nested_ptbl(gp);
 664 }
 665
 666 static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
 667 {
 668         struct kvm_nested_guest *gp;
 669         long shadow_lpid;
 670
 671         gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 672         if (!gp)
 673                 return NULL;
 674         gp->l1_host = kvm;
 675         gp->l1_lpid = lpid;
 676         mutex_init(&gp->tlb_lock);
 677         gp->shadow_pgtable = pgd_alloc(kvm->mm);
 678         if (!gp->shadow_pgtable)
 679                 goto out_free;
 680         shadow_lpid = kvmppc_alloc_lpid();
 681         if (shadow_lpid < 0)
 682                 goto out_free2;
 683         gp->shadow_lpid = shadow_lpid;
 684         gp->radix = 1;
 685
 686         memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu));
 687
 688         return gp;
 689
 690  out_free2:
 691         pgd_free(kvm->mm, gp->shadow_pgtable);
 692  out_free:
 693         kfree(gp);
 694         return NULL;
 695 }
 696
 697 /*
 698  * Free up any resources allocated for a nested guest.
 699  */
 700 static void kvmhv_release_nested(struct kvm_nested_guest *gp)
 701 {
 702         struct kvm *kvm = gp->l1_host;
 703
 704         if (gp->shadow_pgtable) {
 705                 /*
 706                  * No vcpu is using this struct and no call to
 707                  * kvmhv_get_nested can find this struct,
 708                  * so we don't need to hold kvm->mmu_lock.
 709                  */
 710                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
 711                                           gp->shadow_lpid);
 712                 pgd_free(kvm->mm, gp->shadow_pgtable);
 713         }
 714         kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0);
 715         kvmppc_free_lpid(gp->shadow_lpid);
 716         kfree(gp);
 717 }
 718
 719 static void kvmhv_remove_nested(struct kvm_nested_guest *gp)
 720 {
 721         struct kvm *kvm = gp->l1_host;
 722         int lpid = gp->l1_lpid;
 723         long ref;
 724
 725         spin_lock(&kvm->mmu_lock);
 726         if (gp == kvm->arch.nested_guests[lpid]) {
 727                 kvm->arch.nested_guests[lpid] = NULL;
 728                 if (lpid == kvm->arch.max_nested_lpid) {
 729                         while (--lpid >= 0 && !kvm->arch.nested_guests[lpid])
 730                                 ;
 731                         kvm->arch.max_nested_lpid = lpid;
 732                 }
 733                 --gp->refcnt;
 734         }
 735         ref = gp->refcnt;
 736         spin_unlock(&kvm->mmu_lock);
 737         if (ref == 0)
 738                 kvmhv_release_nested(gp);
 739 }
 740
 741 /*
 742  * Free up all nested resources allocated for this guest.
 743  * This is called with no vcpus of the guest running, when
 744  * switching the guest to HPT mode or when destroying the
 745  * guest.
 746  */
 747 void kvmhv_release_all_nested(struct kvm *kvm)
 748 {
 749         int i;
 750         struct kvm_nested_guest *gp;
 751         struct kvm_nested_guest *freelist = NULL;
 752         struct kvm_memory_slot *memslot;
 753         int srcu_idx;
 754
 755         spin_lock(&kvm->mmu_lock);
 756         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
 757                 gp = kvm->arch.nested_guests[i];
 758                 if (!gp)
 759                         continue;
 760                 kvm->arch.nested_guests[i] = NULL;
 761                 if (--gp->refcnt == 0) {
 762                         gp->next = freelist;
 763                         freelist = gp;
 764                 }
 765         }
 766         kvm->arch.max_nested_lpid = -1;
 767         spin_unlock(&kvm->mmu_lock);
 768         while ((gp = freelist) != NULL) {
 769                 freelist = gp->next;
 770                 kvmhv_release_nested(gp);
 771         }
 772
 773         srcu_idx = srcu_read_lock(&kvm->srcu);
 774         kvm_for_each_memslot(memslot, kvm_memslots(kvm))
 775                 kvmhv_free_memslot_nest_rmap(memslot);
 776         srcu_read_unlock(&kvm->srcu, srcu_idx);
 777 }
 778
 779 /* caller must hold gp->tlb_lock */
 780 static void kvmhv_flush_nested(struct kvm_nested_guest *gp)
 781 {
 782         struct kvm *kvm = gp->l1_host;
 783
 784         spin_lock(&kvm->mmu_lock);
 785         kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid);
 786         spin_unlock(&kvm->mmu_lock);
 787         kvmhv_flush_lpid(gp->shadow_lpid);
 788         kvmhv_update_ptbl_cache(gp);
 789         if (gp->l1_gr_to_hr == 0)
 790                 kvmhv_remove_nested(gp);
 791 }
 792
 793 struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
 794                                           bool create)
 795 {
 796         struct kvm_nested_guest *gp, *newgp;
 797
 798         if (l1_lpid >= KVM_MAX_NESTED_GUESTS ||
 799             l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4)))
 800                 return NULL;
 801
 802         spin_lock(&kvm->mmu_lock);
 803         gp = kvm->arch.nested_guests[l1_lpid];
 804         if (gp)
 805                 ++gp->refcnt;
 806         spin_unlock(&kvm->mmu_lock);
 807
 808         if (gp || !create)
 809                 return gp;
 810
 811         newgp = kvmhv_alloc_nested(kvm, l1_lpid);
 812         if (!newgp)
 813                 return NULL;
 814         spin_lock(&kvm->mmu_lock);
 815         if (kvm->arch.nested_guests[l1_lpid]) {
 816                 /* someone else beat us to it */
 817                 gp = kvm->arch.nested_guests[l1_lpid];
 818         } else {
 819                 kvm->arch.nested_guests[l1_lpid] = newgp;
 820                 ++newgp->refcnt;
 821                 gp = newgp;
 822                 newgp = NULL;
 823                 if (l1_lpid > kvm->arch.max_nested_lpid)
 824                         kvm->arch.max_nested_lpid = l1_lpid;
 825         }
 826         ++gp->refcnt;
 827         spin_unlock(&kvm->mmu_lock);
 828
 829         if (newgp)
 830                 kvmhv_release_nested(newgp);
 831
 832         return gp;
 833 }
 834
 835 void kvmhv_put_nested(struct kvm_nested_guest *gp)
 836 {
 837         struct kvm *kvm = gp->l1_host;
 838         long ref;
 839
 840         spin_lock(&kvm->mmu_lock);
 841         ref = --gp->refcnt;
 842         spin_unlock(&kvm->mmu_lock);
 843         if (ref == 0)
 844                 kvmhv_release_nested(gp);
 845 }
 846
 847 static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid)
 848 {
 849         if (lpid > kvm->arch.max_nested_lpid)
 850                 return NULL;
 851         return kvm->arch.nested_guests[lpid];
 852 }
 853
 854 pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid,
 855                                  unsigned long ea, unsigned *hshift)
 856 {
 857         struct kvm_nested_guest *gp;
 858         pte_t *pte;
 859
 860         gp = kvmhv_find_nested(kvm, lpid);
 861         if (!gp)
 862                 return NULL;
 863
 864         VM_WARN(!spin_is_locked(&kvm->mmu_lock),
 865                 "%s called with kvm mmu_lock not held \n", __func__);
 866         pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift);
 867
 868         return pte;
 869 }
 870
 871 static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2)
 872 {
 873         return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK |
 874                                        RMAP_NESTED_GPA_MASK));
 875 }
 876
 877 void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
 878                             struct rmap_nested **n_rmap)
 879 {
 880         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 881         struct rmap_nested *cursor;
 882         u64 rmap, new_rmap = (*n_rmap)->rmap;
 883
 884         /* Are there any existing entries? */
 885         if (!(*rmapp)) {
 886                 /* No -> use the rmap as a single entry */
 887                 *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY;
 888                 return;
 889         }
 890
 891         /* Do any entries match what we're trying to insert? */
 892         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 893                 if (kvmhv_n_rmap_is_equal(rmap, new_rmap))
 894                         return;
 895         }
 896
 897         /* Do we need to create a list or just add the new entry? */
 898         rmap = *rmapp;
 899         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 900                 *rmapp = 0UL;
 901         llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp);
 902         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 903                 (*n_rmap)->list.next = (struct llist_node *) rmap;
 904
 905         /* Set NULL so not freed by caller */
 906         *n_rmap = NULL;
 907 }
 908
 909 static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap,
 910                                       unsigned long clr, unsigned long set,
 911                                       unsigned long hpa, unsigned long mask)
 912 {
 913         unsigned long gpa;
 914         unsigned int shift, lpid;
 915         pte_t *ptep;
 916
 917         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 918         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 919
 920         /* Find the pte */
 921         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 922         /*
 923          * If the pte is present and the pfn is still the same, update the pte.
 924          * If the pfn has changed then this is a stale rmap entry, the nested
 925          * gpa actually points somewhere else now, and there is nothing to do.
 926          * XXX A future optimisation would be to remove the rmap entry here.
 927          */
 928         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) {
 929                 __radix_pte_update(ptep, clr, set);
 930                 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
 931         }
 932 }
 933
 934 /*
 935  * For a given list of rmap entries, update the rc bits in all ptes in shadow
 936  * page tables for nested guests which are referenced by the rmap list.
 937  */
 938 void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp,
 939                                     unsigned long clr, unsigned long set,
 940                                     unsigned long hpa, unsigned long nbytes)
 941 {
 942         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 943         struct rmap_nested *cursor;
 944         unsigned long rmap, mask;
 945
 946         if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED))
 947                 return;
 948
 949         mask = PTE_RPN_MASK & ~(nbytes - 1);
 950         hpa &= mask;
 951
 952         for_each_nest_rmap_safe(cursor, entry, &rmap)
 953                 kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask);
 954 }
 955
 956 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
 957                                    unsigned long hpa, unsigned long mask)
 958 {
 959         struct kvm_nested_guest *gp;
 960         unsigned long gpa;
 961         unsigned int shift, lpid;
 962         pte_t *ptep;
 963
 964         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 965         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 966         gp = kvmhv_find_nested(kvm, lpid);
 967         if (!gp)
 968                 return;
 969
 970         /* Find and invalidate the pte */
 971         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 972         /* Don't spuriously invalidate ptes if the pfn has changed */
 973         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa))
 974                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
 975 }
 976
 977 static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
 978                                         unsigned long hpa, unsigned long mask)
 979 {
 980         struct llist_node *entry = llist_del_all((struct llist_head *) rmapp);
 981         struct rmap_nested *cursor;
 982         unsigned long rmap;
 983
 984         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 985                 kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask);
 986                 kfree(cursor);
 987         }
 988 }
 989
 990 /* called with kvm->mmu_lock held */
 991 void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
 992                                   const struct kvm_memory_slot *memslot,
 993                                   unsigned long gpa, unsigned long hpa,
 994                                   unsigned long nbytes)
 995 {
 996         unsigned long gfn, end_gfn;
 997         unsigned long addr_mask;
 998
 999         if (!memslot)
1000                 return;
1001         gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn;
1002         end_gfn = gfn + (nbytes >> PAGE_SHIFT);
1003
1004         addr_mask = PTE_RPN_MASK & ~(nbytes - 1);
1005         hpa &= addr_mask;
1006
1007         for (; gfn < end_gfn; gfn++) {
1008                 unsigned long *rmap = &memslot->arch.rmap[gfn];
1009                 kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask);
1010         }
1011 }
1012
1013 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free)
1014 {
1015         unsigned long page;
1016
1017         for (page = 0; page < free->npages; page++) {
1018                 unsigned long rmap, *rmapp = &free->arch.rmap[page];
1019                 struct rmap_nested *cursor;
1020                 struct llist_node *entry;
1021
1022                 entry = llist_del_all((struct llist_head *) rmapp);
1023                 for_each_nest_rmap_safe(cursor, entry, &rmap)
1024                         kfree(cursor);
1025         }
1026 }
1027
1028 static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu,
1029                                         struct kvm_nested_guest *gp,
1030                                         long gpa, int *shift_ret)
1031 {
1032         struct kvm *kvm = vcpu->kvm;
1033         bool ret = false;
1034         pte_t *ptep;
1035         int shift;
1036
1037         spin_lock(&kvm->mmu_lock);
1038         ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift);
1039         if (!shift)
1040                 shift = PAGE_SHIFT;
1041         if (ptep && pte_present(*ptep)) {
1042                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
1043                 ret = true;
1044         }
1045         spin_unlock(&kvm->mmu_lock);
1046
1047         if (shift_ret)
1048                 *shift_ret = shift;
1049         return ret;
1050 }
1051
1052 static inline int get_ric(unsigned int instr)
1053 {
1054         return (instr >> 18) & 0x3;
1055 }
1056
1057 static inline int get_prs(unsigned int instr)
1058 {
1059         return (instr >> 17) & 0x1;
1060 }
1061
1062 static inline int get_r(unsigned int instr)
1063 {
1064         return (instr >> 16) & 0x1;
1065 }
1066
1067 static inline int get_lpid(unsigned long r_val)
1068 {
1069         return r_val & 0xffffffff;
1070 }
1071
1072 static inline int get_is(unsigned long r_val)
1073 {
1074         return (r_val >> 10) & 0x3;
1075 }
1076
1077 static inline int get_ap(unsigned long r_val)
1078 {
1079         return (r_val >> 5) & 0x7;
1080 }
1081
1082 static inline long get_epn(unsigned long r_val)
1083 {
1084         return r_val >> 12;
1085 }
1086
1087 static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid,
1088                                         int ap, long epn)
1089 {
1090         struct kvm *kvm = vcpu->kvm;
1091         struct kvm_nested_guest *gp;
1092         long npages;
1093         int shift, shadow_shift;
1094         unsigned long addr;
1095
1096         shift = ap_to_shift(ap);
1097         addr = epn << 12;
1098         if (shift < 0)
1099                 /* Invalid ap encoding */
1100                 return -EINVAL;
1101
1102         addr &= ~((1UL << shift) - 1);
1103         npages = 1UL << (shift - PAGE_SHIFT);
1104
1105         gp = kvmhv_get_nested(kvm, lpid, false);
1106         if (!gp) /* No such guest -> nothing to do */
1107                 return 0;
1108         mutex_lock(&gp->tlb_lock);
1109
1110         /* There may be more than one host page backing this single guest pte */
1111         do {
1112                 kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift);
1113
1114                 npages -= 1UL << (shadow_shift - PAGE_SHIFT);
1115                 addr += 1UL << shadow_shift;
1116         } while (npages > 0);
1117
1118         mutex_unlock(&gp->tlb_lock);
1119         kvmhv_put_nested(gp);
1120         return 0;
1121 }
1122
1123 static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu,
1124                                      struct kvm_nested_guest *gp, int ric)
1125 {
1126         struct kvm *kvm = vcpu->kvm;
1127
1128         mutex_lock(&gp->tlb_lock);
1129         switch (ric) {
1130         case 0:
1131                 /* Invalidate TLB */
1132                 spin_lock(&kvm->mmu_lock);
1133                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
1134                                           gp->shadow_lpid);
1135                 kvmhv_flush_lpid(gp->shadow_lpid);
1136                 spin_unlock(&kvm->mmu_lock);
1137                 break;
1138         case 1:
1139                 /*
1140                  * Invalidate PWC
1141                  * We don't cache this -> nothing to do
1142                  */
1143                 break;
1144         case 2:
1145                 /* Invalidate TLB, PWC and caching of partition table entries */
1146                 kvmhv_flush_nested(gp);
1147                 break;
1148         default:
1149                 break;
1150         }
1151         mutex_unlock(&gp->tlb_lock);
1152 }
1153
1154 static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric)
1155 {
1156         struct kvm *kvm = vcpu->kvm;
1157         struct kvm_nested_guest *gp;
1158         int i;
1159
1160         spin_lock(&kvm->mmu_lock);
1161         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
1162                 gp = kvm->arch.nested_guests[i];
1163                 if (gp) {
1164                         spin_unlock(&kvm->mmu_lock);
1165                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1166                         spin_lock(&kvm->mmu_lock);
1167                 }
1168         }
1169         spin_unlock(&kvm->mmu_lock);
1170 }
1171
1172 static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr,
1173                                     unsigned long rsval, unsigned long rbval)
1174 {
1175         struct kvm *kvm = vcpu->kvm;
1176         struct kvm_nested_guest *gp;
1177         int r, ric, prs, is, ap;
1178         int lpid;
1179         long epn;
1180         int ret = 0;
1181
1182         ric = get_ric(instr);
1183         prs = get_prs(instr);
1184         r = get_r(instr);
1185         lpid = get_lpid(rsval);
1186         is = get_is(rbval);
1187
1188         /*
1189          * These cases are invalid and are not handled:
1190          * r   != 1 -> Only radix supported
1191          * prs == 1 -> Not HV privileged
1192          * ric == 3 -> No cluster bombs for radix
1193          * is  == 1 -> Partition scoped translations not associated with pid
1194          * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA
1195          */
1196         if ((!r) || (prs) || (ric == 3) || (is == 1) ||
1197             ((!is) && (ric == 1 || ric == 2)))
1198                 return -EINVAL;
1199
1200         switch (is) {
1201         case 0:
1202                 /*
1203                  * We know ric == 0
1204                  * Invalidate TLB for a given target address
1205                  */
1206                 epn = get_epn(rbval);
1207                 ap = get_ap(rbval);
1208                 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn);
1209                 break;
1210         case 2:
1211                 /* Invalidate matching LPID */
1212                 gp = kvmhv_get_nested(kvm, lpid, false);
1213                 if (gp) {
1214                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1215                         kvmhv_put_nested(gp);
1216                 }
1217                 break;
1218         case 3:
1219                 /* Invalidate ALL LPIDs */
1220                 kvmhv_emulate_tlbie_all_lpid(vcpu, ric);
1221                 break;
1222         default:
1223                 ret = -EINVAL;
1224                 break;
1225         }
1226
1227         return ret;
1228 }
1229
1230 /*
1231  * This handles the H_TLB_INVALIDATE hcall.
1232  * Parameters are (r4) tlbie instruction code, (r5) rS contents,
1233  * (r6) rB contents.
1234  */
1235 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
1236 {
1237         int ret;
1238
1239         ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4),
1240                         kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6));
1241         if (ret)
1242                 return H_PARAMETER;
1243         return H_SUCCESS;
1244 }
1245
1246 static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
1247                                          unsigned long lpid, unsigned long ric)
1248 {
1249         struct kvm *kvm = vcpu->kvm;
1250         struct kvm_nested_guest *gp;
1251
1252         gp = kvmhv_get_nested(kvm, lpid, false);
1253         if (gp) {
1254                 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1255                 kvmhv_put_nested(gp);
1256         }
1257         return H_SUCCESS;
1258 }
1259
1260 /*
1261  * Number of pages above which we invalidate the entire LPID rather than
1262  * flush individual pages.
1263  */
1264 static unsigned long tlb_range_flush_page_ceiling __read_mostly = 33;
1265
1266 static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
1267                                          unsigned long lpid,
1268                                          unsigned long pg_sizes,
1269                                          unsigned long start,
1270                                          unsigned long end)
1271 {
1272         int ret = H_P4;
1273         unsigned long addr, nr_pages;
1274         struct mmu_psize_def *def;
1275         unsigned long psize, ap, page_size;
1276         bool flush_lpid;
1277
1278         for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
1279                 def = &mmu_psize_defs[psize];
1280                 if (!(pg_sizes & def->h_rpt_pgsize))
1281                         continue;
1282
1283                 nr_pages = (end - start) >> def->shift;
1284                 flush_lpid = nr_pages > tlb_range_flush_page_ceiling;
1285                 if (flush_lpid)
1286                         return do_tlb_invalidate_nested_all(vcpu, lpid,
1287                                                         RIC_FLUSH_TLB);
1288                 addr = start;
1289                 ap = mmu_get_ap(psize);
1290                 page_size = 1UL << def->shift;
1291                 do {
1292                         ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
1293                                                    get_epn(addr));
1294                         if (ret)
1295                                 return H_P4;
1296                         addr += page_size;
1297                 } while (addr < end);
1298         }
1299         return ret;
1300 }
1301
1302 /*
1303  * Performs partition-scoped invalidations for nested guests
1304  * as part of H_RPT_INVALIDATE hcall.
1305  */
1306 long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
1307                              unsigned long type, unsigned long pg_sizes,
1308                              unsigned long start, unsigned long end)
1309 {
1310         /*
1311          * If L2 lpid isn't valid, we need to return H_PARAMETER.
1312          *
1313          * However, nested KVM issues a L2 lpid flush call when creating
1314          * partition table entries for L2. This happens even before the
1315          * corresponding shadow lpid is created in HV which happens in
1316          * H_ENTER_NESTED call. Since we can't differentiate this case from
1317          * the invalid case, we ignore such flush requests and return success.
1318          */
1319         if (!kvmhv_find_nested(vcpu->kvm, lpid))
1320                 return H_SUCCESS;
1321
1322         /*
1323          * A flush all request can be handled by a full lpid flush only.
1324          */
1325         if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
1326                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
1327
1328         /*
1329          * We don't need to handle a PWC flush like process table here,
1330          * because intermediate partition scoped table in nested guest doesn't
1331          * really have PWC. Only level we have PWC is in L0 and for nested
1332          * invalidate at L0 we always do kvm_flush_lpid() which does
1333          * radix__flush_all_lpid(). For range invalidate at any level, we
1334          * are not removing the higher level page tables and hence there is
1335          * no PWC invalidate needed.
1336          *
1337          * if (type & H_RPTI_TYPE_PWC) {
1338          *      ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
1339          *      if (ret)
1340          *              return H_P4;
1341          * }
1342          */
1343
1344         if (start == 0 && end == -1)
1345                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
1346
1347         if (type & H_RPTI_TYPE_TLB)
1348                 return do_tlb_invalidate_nested_tlb(vcpu, lpid, pg_sizes,
1349                                                     start, end);
1350         return H_SUCCESS;
1351 }
1352
1353 /* Used to convert a nested guest real address to a L1 guest real address */
1354 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
1355                                        struct kvm_nested_guest *gp,
1356                                        unsigned long n_gpa, unsigned long dsisr,
1357                                        struct kvmppc_pte *gpte_p)
1358 {
1359         u64 fault_addr, flags = dsisr & DSISR_ISSTORE;
1360         int ret;
1361
1362         ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr,
1363                                          &fault_addr);
1364
1365         if (ret) {
1366                 /* We didn't find a pte */
1367                 if (ret == -EINVAL) {
1368                         /* Unsupported mmu config */
1369                         flags |= DSISR_UNSUPP_MMU;
1370                 } else if (ret == -ENOENT) {
1371                         /* No translation found */
1372                         flags |= DSISR_NOHPTE;
1373                 } else if (ret == -EFAULT) {
1374                         /* Couldn't access L1 real address */
1375                         flags |= DSISR_PRTABLE_FAULT;
1376                         vcpu->arch.fault_gpa = fault_addr;
1377                 } else {
1378                         /* Unknown error */
1379                         return ret;
1380                 }
1381                 goto forward_to_l1;
1382         } else {
1383                 /* We found a pte -> check permissions */
1384                 if (dsisr & DSISR_ISSTORE) {
1385                         /* Can we write? */
1386                         if (!gpte_p->may_write) {
1387                                 flags |= DSISR_PROTFAULT;
1388                                 goto forward_to_l1;
1389                         }
1390                 } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1391                         /* Can we execute? */
1392                         if (!gpte_p->may_execute) {
1393                                 flags |= SRR1_ISI_N_G_OR_CIP;
1394                                 goto forward_to_l1;
1395                         }
1396                 } else {
1397                         /* Can we read? */
1398                         if (!gpte_p->may_read && !gpte_p->may_write) {
1399                                 flags |= DSISR_PROTFAULT;
1400                                 goto forward_to_l1;
1401                         }
1402                 }
1403         }
1404
1405         return 0;
1406
1407 forward_to_l1:
1408         vcpu->arch.fault_dsisr = flags;
1409         if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1410                 vcpu->arch.shregs.msr &= SRR1_MSR_BITS;
1411                 vcpu->arch.shregs.msr |= flags;
1412         }
1413         return RESUME_HOST;
1414 }
1415
1416 static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
1417                                        struct kvm_nested_guest *gp,
1418                                        unsigned long n_gpa,
1419                                        struct kvmppc_pte gpte,
1420                                        unsigned long dsisr)
1421 {
1422         struct kvm *kvm = vcpu->kvm;
1423         bool writing = !!(dsisr & DSISR_ISSTORE);
1424         u64 pgflags;
1425         long ret;
1426
1427         /* Are the rc bits set in the L1 partition scoped pte? */
1428         pgflags = _PAGE_ACCESSED;
1429         if (writing)
1430                 pgflags |= _PAGE_DIRTY;
1431         if (pgflags & ~gpte.rc)
1432                 return RESUME_HOST;
1433
1434         spin_lock(&kvm->mmu_lock);
1435         /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
1436         ret = kvmppc_hv_handle_set_rc(kvm, false, writing,
1437                                       gpte.raddr, kvm->arch.lpid);
1438         if (!ret) {
1439                 ret = -EINVAL;
1440                 goto out_unlock;
1441         }
1442
1443         /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
1444         ret = kvmppc_hv_handle_set_rc(kvm, true, writing,
1445                                       n_gpa, gp->l1_lpid);
1446         if (!ret)
1447                 ret = -EINVAL;
1448         else
1449                 ret = 0;
1450
1451 out_unlock:
1452         spin_unlock(&kvm->mmu_lock);
1453         return ret;
1454 }
1455
1456 static inline int kvmppc_radix_level_to_shift(int level)
1457 {
1458         switch (level) {
1459         case 2:
1460                 return PUD_SHIFT;
1461         case 1:
1462                 return PMD_SHIFT;
1463         default:
1464                 return PAGE_SHIFT;
1465         }
1466 }
1467
1468 static inline int kvmppc_radix_shift_to_level(int shift)
1469 {
1470         if (shift == PUD_SHIFT)
1471                 return 2;
1472         if (shift == PMD_SHIFT)
1473                 return 1;
1474         if (shift == PAGE_SHIFT)
1475                 return 0;
1476         WARN_ON_ONCE(1);
1477         return 0;
1478 }
1479
1480 /* called with gp->tlb_lock held */
1481 static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
1482                                           struct kvm_nested_guest *gp)
1483 {
1484         struct kvm *kvm = vcpu->kvm;
1485         struct kvm_memory_slot *memslot;
1486         struct rmap_nested *n_rmap;
1487         struct kvmppc_pte gpte;
1488         pte_t pte, *pte_p;
1489         unsigned long mmu_seq;
1490         unsigned long dsisr = vcpu->arch.fault_dsisr;
1491         unsigned long ea = vcpu->arch.fault_dar;
1492         unsigned long *rmapp;
1493         unsigned long n_gpa, gpa, gfn, perm = 0UL;
1494         unsigned int shift, l1_shift, level;
1495         bool writing = !!(dsisr & DSISR_ISSTORE);
1496         bool kvm_ro = false;
1497         long int ret;
1498
1499         if (!gp->l1_gr_to_hr) {
1500                 kvmhv_update_ptbl_cache(gp);
1501                 if (!gp->l1_gr_to_hr)
1502                         return RESUME_HOST;
1503         }
1504
1505         /* Convert the nested guest real address into a L1 guest real address */
1506
1507         n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL;
1508         if (!(dsisr & DSISR_PRTABLE_FAULT))
1509                 n_gpa |= ea & 0xFFF;
1510         ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte);
1511
1512         /*
1513          * If the hardware found a translation but we don't now have a usable
1514          * translation in the l1 partition-scoped tree, remove the shadow pte
1515          * and let the guest retry.
1516          */
1517         if (ret == RESUME_HOST &&
1518             (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G |
1519                       DSISR_BAD_COPYPASTE)))
1520                 goto inval;
1521         if (ret)
1522                 return ret;
1523
1524         /* Failed to set the reference/change bits */
1525         if (dsisr & DSISR_SET_RC) {
1526                 ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr);
1527                 if (ret == RESUME_HOST)
1528                         return ret;
1529                 if (ret)
1530                         goto inval;
1531                 dsisr &= ~DSISR_SET_RC;
1532                 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
1533                                DSISR_PROTFAULT)))
1534                         return RESUME_GUEST;
1535         }
1536
1537         /*
1538          * We took an HISI or HDSI while we were running a nested guest which
1539          * means we have no partition scoped translation for that. This means
1540          * we need to insert a pte for the mapping into our shadow_pgtable.
1541          */
1542
1543         l1_shift = gpte.page_shift;
1544         if (l1_shift < PAGE_SHIFT) {
1545                 /* We don't support l1 using a page size smaller than our own */
1546                 pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n",
1547                         l1_shift, PAGE_SHIFT);
1548                 return -EINVAL;
1549         }
1550         gpa = gpte.raddr;
1551         gfn = gpa >> PAGE_SHIFT;
1552
1553         /* 1. Get the corresponding host memslot */
1554
1555         memslot = gfn_to_memslot(kvm, gfn);
1556         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
1557                 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) {
1558                         /* unusual error -> reflect to the guest as a DSI */
1559                         kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
1560                         return RESUME_GUEST;
1561                 }
1562
1563                 /* passthrough of emulated MMIO case */
1564                 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing);
1565         }
1566         if (memslot->flags & KVM_MEM_READONLY) {
1567                 if (writing) {
1568                         /* Give the guest a DSI */
1569                         kvmppc_core_queue_data_storage(vcpu, ea,
1570                                         DSISR_ISSTORE | DSISR_PROTFAULT);
1571                         return RESUME_GUEST;
1572                 }
1573                 kvm_ro = true;
1574         }
1575
1576         /* 2. Find the host pte for this L1 guest real address */
1577
1578         /* Used to check for invalidations in progress */
1579         mmu_seq = kvm->mmu_notifier_seq;
1580         smp_rmb();
1581
1582         /* See if can find translation in our partition scoped tables for L1 */
1583         pte = __pte(0);
1584         spin_lock(&kvm->mmu_lock);
1585         pte_p = find_kvm_secondary_pte(kvm, gpa, &shift);
1586         if (!shift)
1587                 shift = PAGE_SHIFT;
1588         if (pte_p)
1589                 pte = *pte_p;
1590         spin_unlock(&kvm->mmu_lock);
1591
1592         if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) {
1593                 /* No suitable pte found -> try to insert a mapping */
1594                 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot,
1595                                         writing, kvm_ro, &pte, &level);
1596                 if (ret == -EAGAIN)
1597                         return RESUME_GUEST;
1598                 else if (ret)
1599                         return ret;
1600                 shift = kvmppc_radix_level_to_shift(level);
1601         }
1602         /* Align gfn to the start of the page */
1603         gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT;
1604
1605         /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */
1606
1607         /* The permissions is the combination of the host and l1 guest ptes */
1608         perm |= gpte.may_read ? 0UL : _PAGE_READ;
1609         perm |= gpte.may_write ? 0UL : _PAGE_WRITE;
1610         perm |= gpte.may_execute ? 0UL : _PAGE_EXEC;
1611         /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */
1612         perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED;
1613         perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY;
1614         pte = __pte(pte_val(pte) & ~perm);
1615
1616         /* What size pte can we insert? */
1617         if (shift > l1_shift) {
1618                 u64 mask;
1619                 unsigned int actual_shift = PAGE_SHIFT;
1620                 if (PMD_SHIFT < l1_shift)
1621                         actual_shift = PMD_SHIFT;
1622                 mask = (1UL << shift) - (1UL << actual_shift);
1623                 pte = __pte(pte_val(pte) | (gpa & mask));
1624                 shift = actual_shift;
1625         }
1626         level = kvmppc_radix_shift_to_level(shift);
1627         n_gpa &= ~((1UL << shift) - 1);
1628
1629         /* 4. Insert the pte into our shadow_pgtable */
1630
1631         n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL);
1632         if (!n_rmap)
1633                 return RESUME_GUEST; /* Let the guest try again */
1634         n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) |
1635                 (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT);
1636         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1637         ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level,
1638                                 mmu_seq, gp->shadow_lpid, rmapp, &n_rmap);
1639         kfree(n_rmap);
1640         if (ret == -EAGAIN)
1641                 ret = RESUME_GUEST;     /* Let the guest try again */
1642
1643         return ret;
1644
1645  inval:
1646         kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL);
1647         return RESUME_GUEST;
1648 }
1649
1650 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu)
1651 {
1652         struct kvm_nested_guest *gp = vcpu->arch.nested;
1653         long int ret;
1654
1655         mutex_lock(&gp->tlb_lock);
1656         ret = __kvmhv_nested_page_fault(vcpu, gp);
1657         mutex_unlock(&gp->tlb_lock);
1658         return ret;
1659 }
1660
1661 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid)
1662 {
1663         int ret = -1;
1664
1665         spin_lock(&kvm->mmu_lock);
1666         while (++lpid <= kvm->arch.max_nested_lpid) {
1667                 if (kvm->arch.nested_guests[lpid]) {
1668                         ret = lpid;
1669                         break;
1670                 }
1671         }
1672         spin_unlock(&kvm->mmu_lock);
1673         return ret;
1674 }