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
  23 static struct patb_entry *pseries_partition_tb;
  24
  25 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp);
  26 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free);
  27
  28 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
  29 {
  30         struct kvmppc_vcore *vc = vcpu->arch.vcore;
  31
  32         hr->pcr = vc->pcr | PCR_MASK;
  33         hr->dpdes = vc->dpdes;
  34         hr->hfscr = vcpu->arch.hfscr;
  35         hr->tb_offset = vc->tb_offset;
  36         hr->dawr0 = vcpu->arch.dawr0;
  37         hr->dawrx0 = vcpu->arch.dawrx0;
  38         hr->ciabr = vcpu->arch.ciabr;
  39         hr->purr = vcpu->arch.purr;
  40         hr->spurr = vcpu->arch.spurr;
  41         hr->ic = vcpu->arch.ic;
  42         hr->vtb = vc->vtb;
  43         hr->srr0 = vcpu->arch.shregs.srr0;
  44         hr->srr1 = vcpu->arch.shregs.srr1;
  45         hr->sprg[0] = vcpu->arch.shregs.sprg0;
  46         hr->sprg[1] = vcpu->arch.shregs.sprg1;
  47         hr->sprg[2] = vcpu->arch.shregs.sprg2;
  48         hr->sprg[3] = vcpu->arch.shregs.sprg3;
  49         hr->pidr = vcpu->arch.pid;
  50         hr->cfar = vcpu->arch.cfar;
  51         hr->ppr = vcpu->arch.ppr;
  52         hr->dawr1 = vcpu->arch.dawr1;
  53         hr->dawrx1 = vcpu->arch.dawrx1;
  54 }
  55
  56 static void byteswap_pt_regs(struct pt_regs *regs)
  57 {
  58         unsigned long *addr = (unsigned long *) regs;
  59
  60         for (; addr < ((unsigned long *) (regs + 1)); addr++)
  61                 *addr = swab64(*addr);
  62 }
  63
  64 static void byteswap_hv_regs(struct hv_guest_state *hr)
  65 {
  66         hr->version = swab64(hr->version);
  67         hr->lpid = swab32(hr->lpid);
  68         hr->vcpu_token = swab32(hr->vcpu_token);
  69         hr->lpcr = swab64(hr->lpcr);
  70         hr->pcr = swab64(hr->pcr) | PCR_MASK;
  71         hr->amor = swab64(hr->amor);
  72         hr->dpdes = swab64(hr->dpdes);
  73         hr->hfscr = swab64(hr->hfscr);
  74         hr->tb_offset = swab64(hr->tb_offset);
  75         hr->dawr0 = swab64(hr->dawr0);
  76         hr->dawrx0 = swab64(hr->dawrx0);
  77         hr->ciabr = swab64(hr->ciabr);
  78         hr->hdec_expiry = swab64(hr->hdec_expiry);
  79         hr->purr = swab64(hr->purr);
  80         hr->spurr = swab64(hr->spurr);
  81         hr->ic = swab64(hr->ic);
  82         hr->vtb = swab64(hr->vtb);
  83         hr->hdar = swab64(hr->hdar);
  84         hr->hdsisr = swab64(hr->hdsisr);
  85         hr->heir = swab64(hr->heir);
  86         hr->asdr = swab64(hr->asdr);
  87         hr->srr0 = swab64(hr->srr0);
  88         hr->srr1 = swab64(hr->srr1);
  89         hr->sprg[0] = swab64(hr->sprg[0]);
  90         hr->sprg[1] = swab64(hr->sprg[1]);
  91         hr->sprg[2] = swab64(hr->sprg[2]);
  92         hr->sprg[3] = swab64(hr->sprg[3]);
  93         hr->pidr = swab64(hr->pidr);
  94         hr->cfar = swab64(hr->cfar);
  95         hr->ppr = swab64(hr->ppr);
  96         hr->dawr1 = swab64(hr->dawr1);
  97         hr->dawrx1 = swab64(hr->dawrx1);
  98 }
  99
 100 static void save_hv_return_state(struct kvm_vcpu *vcpu, int trap,
 101                                  struct hv_guest_state *hr)
 102 {
 103         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 104
 105         hr->dpdes = vc->dpdes;
 106         hr->hfscr = vcpu->arch.hfscr;
 107         hr->purr = vcpu->arch.purr;
 108         hr->spurr = vcpu->arch.spurr;
 109         hr->ic = vcpu->arch.ic;
 110         hr->vtb = vc->vtb;
 111         hr->srr0 = vcpu->arch.shregs.srr0;
 112         hr->srr1 = vcpu->arch.shregs.srr1;
 113         hr->sprg[0] = vcpu->arch.shregs.sprg0;
 114         hr->sprg[1] = vcpu->arch.shregs.sprg1;
 115         hr->sprg[2] = vcpu->arch.shregs.sprg2;
 116         hr->sprg[3] = vcpu->arch.shregs.sprg3;
 117         hr->pidr = vcpu->arch.pid;
 118         hr->cfar = vcpu->arch.cfar;
 119         hr->ppr = vcpu->arch.ppr;
 120         switch (trap) {
 121         case BOOK3S_INTERRUPT_H_DATA_STORAGE:
 122                 hr->hdar = vcpu->arch.fault_dar;
 123                 hr->hdsisr = vcpu->arch.fault_dsisr;
 124                 hr->asdr = vcpu->arch.fault_gpa;
 125                 break;
 126         case BOOK3S_INTERRUPT_H_INST_STORAGE:
 127                 hr->asdr = vcpu->arch.fault_gpa;
 128                 break;
 129         case BOOK3S_INTERRUPT_H_EMUL_ASSIST:
 130                 hr->heir = vcpu->arch.emul_inst;
 131                 break;
 132         }
 133 }
 134
 135 /*
 136  * This can result in some L0 HV register state being leaked to an L1
 137  * hypervisor when the hv_guest_state is copied back to the guest after
 138  * being modified here.
 139  *
 140  * There is no known problem with such a leak, and in many cases these
 141  * register settings could be derived by the guest by observing behaviour
 142  * and timing, interrupts, etc., but it is an issue to consider.
 143  */
 144 static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
 145 {
 146         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 147         u64 mask;
 148
 149         /*
 150          * Don't let L1 change LPCR bits for the L2 except these:
 151          */
 152         mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD |
 153                 LPCR_LPES | LPCR_MER;
 154
 155         /*
 156          * Additional filtering is required depending on hardware
 157          * and configuration.
 158          */
 159         hr->lpcr = kvmppc_filter_lpcr_hv(vcpu->kvm,
 160                         (vc->lpcr & ~mask) | (hr->lpcr & mask));
 161
 162         /*
 163          * Don't let L1 enable features for L2 which we've disabled for L1,
 164          * but preserve the interrupt cause field.
 165          */
 166         hr->hfscr &= (HFSCR_INTR_CAUSE | vcpu->arch.hfscr);
 167
 168         /* Don't let data address watchpoint match in hypervisor state */
 169         hr->dawrx0 &= ~DAWRX_HYP;
 170         hr->dawrx1 &= ~DAWRX_HYP;
 171
 172         /* Don't let completed instruction address breakpt match in HV state */
 173         if ((hr->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER)
 174                 hr->ciabr &= ~CIABR_PRIV;
 175 }
 176
 177 static void restore_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr)
 178 {
 179         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 180
 181         vc->pcr = hr->pcr | PCR_MASK;
 182         vc->dpdes = hr->dpdes;
 183         vcpu->arch.hfscr = hr->hfscr;
 184         vcpu->arch.dawr0 = hr->dawr0;
 185         vcpu->arch.dawrx0 = hr->dawrx0;
 186         vcpu->arch.ciabr = hr->ciabr;
 187         vcpu->arch.purr = hr->purr;
 188         vcpu->arch.spurr = hr->spurr;
 189         vcpu->arch.ic = hr->ic;
 190         vc->vtb = hr->vtb;
 191         vcpu->arch.shregs.srr0 = hr->srr0;
 192         vcpu->arch.shregs.srr1 = hr->srr1;
 193         vcpu->arch.shregs.sprg0 = hr->sprg[0];
 194         vcpu->arch.shregs.sprg1 = hr->sprg[1];
 195         vcpu->arch.shregs.sprg2 = hr->sprg[2];
 196         vcpu->arch.shregs.sprg3 = hr->sprg[3];
 197         vcpu->arch.pid = hr->pidr;
 198         vcpu->arch.cfar = hr->cfar;
 199         vcpu->arch.ppr = hr->ppr;
 200         vcpu->arch.dawr1 = hr->dawr1;
 201         vcpu->arch.dawrx1 = hr->dawrx1;
 202 }
 203
 204 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
 205                                    struct hv_guest_state *hr)
 206 {
 207         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 208
 209         vc->dpdes = hr->dpdes;
 210         vcpu->arch.hfscr = hr->hfscr;
 211         vcpu->arch.purr = hr->purr;
 212         vcpu->arch.spurr = hr->spurr;
 213         vcpu->arch.ic = hr->ic;
 214         vc->vtb = hr->vtb;
 215         vcpu->arch.fault_dar = hr->hdar;
 216         vcpu->arch.fault_dsisr = hr->hdsisr;
 217         vcpu->arch.fault_gpa = hr->asdr;
 218         vcpu->arch.emul_inst = hr->heir;
 219         vcpu->arch.shregs.srr0 = hr->srr0;
 220         vcpu->arch.shregs.srr1 = hr->srr1;
 221         vcpu->arch.shregs.sprg0 = hr->sprg[0];
 222         vcpu->arch.shregs.sprg1 = hr->sprg[1];
 223         vcpu->arch.shregs.sprg2 = hr->sprg[2];
 224         vcpu->arch.shregs.sprg3 = hr->sprg[3];
 225         vcpu->arch.pid = hr->pidr;
 226         vcpu->arch.cfar = hr->cfar;
 227         vcpu->arch.ppr = hr->ppr;
 228 }
 229
 230 static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr)
 231 {
 232         /* No need to reflect the page fault to L1, we've handled it */
 233         vcpu->arch.trap = 0;
 234
 235         /*
 236          * Since the L2 gprs have already been written back into L1 memory when
 237          * we complete the mmio, store the L1 memory location of the L2 gpr
 238          * being loaded into by the mmio so that the loaded value can be
 239          * written there in kvmppc_complete_mmio_load()
 240          */
 241         if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR)
 242             && (vcpu->mmio_is_write == 0)) {
 243                 vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr +
 244                                            offsetof(struct pt_regs,
 245                                                     gpr[vcpu->arch.io_gpr]);
 246                 vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR;
 247         }
 248 }
 249
 250 static int kvmhv_read_guest_state_and_regs(struct kvm_vcpu *vcpu,
 251                                            struct hv_guest_state *l2_hv,
 252                                            struct pt_regs *l2_regs,
 253                                            u64 hv_ptr, u64 regs_ptr)
 254 {
 255         int size;
 256
 257         if (kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv->version,
 258                                 sizeof(l2_hv->version)))
 259                 return -1;
 260
 261         if (kvmppc_need_byteswap(vcpu))
 262                 l2_hv->version = swab64(l2_hv->version);
 263
 264         size = hv_guest_state_size(l2_hv->version);
 265         if (size < 0)
 266                 return -1;
 267
 268         return kvm_vcpu_read_guest(vcpu, hv_ptr, l2_hv, size) ||
 269                 kvm_vcpu_read_guest(vcpu, regs_ptr, l2_regs,
 270                                     sizeof(struct pt_regs));
 271 }
 272
 273 static int kvmhv_write_guest_state_and_regs(struct kvm_vcpu *vcpu,
 274                                             struct hv_guest_state *l2_hv,
 275                                             struct pt_regs *l2_regs,
 276                                             u64 hv_ptr, u64 regs_ptr)
 277 {
 278         int size;
 279
 280         size = hv_guest_state_size(l2_hv->version);
 281         if (size < 0)
 282                 return -1;
 283
 284         return kvm_vcpu_write_guest(vcpu, hv_ptr, l2_hv, size) ||
 285                 kvm_vcpu_write_guest(vcpu, regs_ptr, l2_regs,
 286                                      sizeof(struct pt_regs));
 287 }
 288
 289 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
 290 {
 291         long int err, r;
 292         struct kvm_nested_guest *l2;
 293         struct pt_regs l2_regs, saved_l1_regs;
 294         struct hv_guest_state l2_hv = {0}, saved_l1_hv;
 295         struct kvmppc_vcore *vc = vcpu->arch.vcore;
 296         u64 hv_ptr, regs_ptr;
 297         u64 hdec_exp;
 298         s64 delta_purr, delta_spurr, delta_ic, delta_vtb;
 299
 300         if (vcpu->kvm->arch.l1_ptcr == 0)
 301                 return H_NOT_AVAILABLE;
 302
 303         /* copy parameters in */
 304         hv_ptr = kvmppc_get_gpr(vcpu, 4);
 305         regs_ptr = kvmppc_get_gpr(vcpu, 5);
 306         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 307         err = kvmhv_read_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 308                                               hv_ptr, regs_ptr);
 309         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 310         if (err)
 311                 return H_PARAMETER;
 312
 313         if (kvmppc_need_byteswap(vcpu))
 314                 byteswap_hv_regs(&l2_hv);
 315         if (l2_hv.version > HV_GUEST_STATE_VERSION)
 316                 return H_P2;
 317
 318         if (kvmppc_need_byteswap(vcpu))
 319                 byteswap_pt_regs(&l2_regs);
 320         if (l2_hv.vcpu_token >= NR_CPUS)
 321                 return H_PARAMETER;
 322
 323         /* translate lpid */
 324         l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true);
 325         if (!l2)
 326                 return H_PARAMETER;
 327         if (!l2->l1_gr_to_hr) {
 328                 mutex_lock(&l2->tlb_lock);
 329                 kvmhv_update_ptbl_cache(l2);
 330                 mutex_unlock(&l2->tlb_lock);
 331         }
 332
 333         /* save l1 values of things */
 334         vcpu->arch.regs.msr = vcpu->arch.shregs.msr;
 335         saved_l1_regs = vcpu->arch.regs;
 336         kvmhv_save_hv_regs(vcpu, &saved_l1_hv);
 337
 338         /* convert TB values/offsets to host (L0) values */
 339         hdec_exp = l2_hv.hdec_expiry - vc->tb_offset;
 340         vc->tb_offset += l2_hv.tb_offset;
 341
 342         /* set L1 state to L2 state */
 343         vcpu->arch.nested = l2;
 344         vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token;
 345         vcpu->arch.regs = l2_regs;
 346
 347         /* Guest must always run with ME enabled, HV disabled. */
 348         vcpu->arch.shregs.msr = (vcpu->arch.regs.msr | MSR_ME) & ~MSR_HV;
 349
 350         sanitise_hv_regs(vcpu, &l2_hv);
 351         restore_hv_regs(vcpu, &l2_hv);
 352
 353         vcpu->arch.ret = RESUME_GUEST;
 354         vcpu->arch.trap = 0;
 355         do {
 356                 if (mftb() >= hdec_exp) {
 357                         vcpu->arch.trap = BOOK3S_INTERRUPT_HV_DECREMENTER;
 358                         r = RESUME_HOST;
 359                         break;
 360                 }
 361                 r = kvmhv_run_single_vcpu(vcpu, hdec_exp, l2_hv.lpcr);
 362         } while (is_kvmppc_resume_guest(r));
 363
 364         /* save L2 state for return */
 365         l2_regs = vcpu->arch.regs;
 366         l2_regs.msr = vcpu->arch.shregs.msr;
 367         delta_purr = vcpu->arch.purr - l2_hv.purr;
 368         delta_spurr = vcpu->arch.spurr - l2_hv.spurr;
 369         delta_ic = vcpu->arch.ic - l2_hv.ic;
 370         delta_vtb = vc->vtb - l2_hv.vtb;
 371         save_hv_return_state(vcpu, vcpu->arch.trap, &l2_hv);
 372
 373         /* restore L1 state */
 374         vcpu->arch.nested = NULL;
 375         vcpu->arch.regs = saved_l1_regs;
 376         vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK;
 377         /* set L1 MSR TS field according to L2 transaction state */
 378         if (l2_regs.msr & MSR_TS_MASK)
 379                 vcpu->arch.shregs.msr |= MSR_TS_S;
 380         vc->tb_offset = saved_l1_hv.tb_offset;
 381         restore_hv_regs(vcpu, &saved_l1_hv);
 382         vcpu->arch.purr += delta_purr;
 383         vcpu->arch.spurr += delta_spurr;
 384         vcpu->arch.ic += delta_ic;
 385         vc->vtb += delta_vtb;
 386
 387         kvmhv_put_nested(l2);
 388
 389         /* copy l2_hv_state and regs back to guest */
 390         if (kvmppc_need_byteswap(vcpu)) {
 391                 byteswap_hv_regs(&l2_hv);
 392                 byteswap_pt_regs(&l2_regs);
 393         }
 394         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 395         err = kvmhv_write_guest_state_and_regs(vcpu, &l2_hv, &l2_regs,
 396                                                hv_ptr, regs_ptr);
 397         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 398         if (err)
 399                 return H_AUTHORITY;
 400
 401         if (r == -EINTR)
 402                 return H_INTERRUPT;
 403
 404         if (vcpu->mmio_needed) {
 405                 kvmhv_nested_mmio_needed(vcpu, regs_ptr);
 406                 return H_TOO_HARD;
 407         }
 408
 409         return vcpu->arch.trap;
 410 }
 411
 412 long kvmhv_nested_init(void)
 413 {
 414         long int ptb_order;
 415         unsigned long ptcr;
 416         long rc;
 417
 418         if (!kvmhv_on_pseries())
 419                 return 0;
 420         if (!radix_enabled())
 421                 return -ENODEV;
 422
 423         /* find log base 2 of KVMPPC_NR_LPIDS, rounding up */
 424         ptb_order = __ilog2(KVMPPC_NR_LPIDS - 1) + 1;
 425         if (ptb_order < 8)
 426                 ptb_order = 8;
 427         pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order,
 428                                        GFP_KERNEL);
 429         if (!pseries_partition_tb) {
 430                 pr_err("kvm-hv: failed to allocated nested partition table\n");
 431                 return -ENOMEM;
 432         }
 433
 434         ptcr = __pa(pseries_partition_tb) | (ptb_order - 8);
 435         rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr);
 436         if (rc != H_SUCCESS) {
 437                 pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n",
 438                        rc);
 439                 kfree(pseries_partition_tb);
 440                 pseries_partition_tb = NULL;
 441                 return -ENODEV;
 442         }
 443
 444         return 0;
 445 }
 446
 447 void kvmhv_nested_exit(void)
 448 {
 449         /*
 450          * N.B. the kvmhv_on_pseries() test is there because it enables
 451          * the compiler to remove the call to plpar_hcall_norets()
 452          * when CONFIG_PPC_PSERIES=n.
 453          */
 454         if (kvmhv_on_pseries() && pseries_partition_tb) {
 455                 plpar_hcall_norets(H_SET_PARTITION_TABLE, 0);
 456                 kfree(pseries_partition_tb);
 457                 pseries_partition_tb = NULL;
 458         }
 459 }
 460
 461 static void kvmhv_flush_lpid(unsigned int lpid)
 462 {
 463         long rc;
 464
 465         if (!kvmhv_on_pseries()) {
 466                 radix__flush_all_lpid(lpid);
 467                 return;
 468         }
 469
 470         rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1),
 471                                 lpid, TLBIEL_INVAL_SET_LPID);
 472         if (rc)
 473                 pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc);
 474 }
 475
 476 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1)
 477 {
 478         if (!kvmhv_on_pseries()) {
 479                 mmu_partition_table_set_entry(lpid, dw0, dw1, true);
 480                 return;
 481         }
 482
 483         pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
 484         pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
 485         /* L0 will do the necessary barriers */
 486         kvmhv_flush_lpid(lpid);
 487 }
 488
 489 static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp)
 490 {
 491         unsigned long dw0;
 492
 493         dw0 = PATB_HR | radix__get_tree_size() |
 494                 __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE;
 495         kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table);
 496 }
 497
 498 void kvmhv_vm_nested_init(struct kvm *kvm)
 499 {
 500         kvm->arch.max_nested_lpid = -1;
 501 }
 502
 503 /*
 504  * Handle the H_SET_PARTITION_TABLE hcall.
 505  * r4 = guest real address of partition table + log_2(size) - 12
 506  * (formatted as for the PTCR).
 507  */
 508 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu)
 509 {
 510         struct kvm *kvm = vcpu->kvm;
 511         unsigned long ptcr = kvmppc_get_gpr(vcpu, 4);
 512         int srcu_idx;
 513         long ret = H_SUCCESS;
 514
 515         srcu_idx = srcu_read_lock(&kvm->srcu);
 516         /*
 517          * Limit the partition table to 4096 entries (because that's what
 518          * hardware supports), and check the base address.
 519          */
 520         if ((ptcr & PRTS_MASK) > 12 - 8 ||
 521             !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT))
 522                 ret = H_PARAMETER;
 523         srcu_read_unlock(&kvm->srcu, srcu_idx);
 524         if (ret == H_SUCCESS)
 525                 kvm->arch.l1_ptcr = ptcr;
 526         return ret;
 527 }
 528
 529 /*
 530  * Handle the H_COPY_TOFROM_GUEST hcall.
 531  * r4 = L1 lpid of nested guest
 532  * r5 = pid
 533  * r6 = eaddr to access
 534  * r7 = to buffer (L1 gpa)
 535  * r8 = from buffer (L1 gpa)
 536  * r9 = n bytes to copy
 537  */
 538 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu)
 539 {
 540         struct kvm_nested_guest *gp;
 541         int l1_lpid = kvmppc_get_gpr(vcpu, 4);
 542         int pid = kvmppc_get_gpr(vcpu, 5);
 543         gva_t eaddr = kvmppc_get_gpr(vcpu, 6);
 544         gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7);
 545         gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8);
 546         void *buf;
 547         unsigned long n = kvmppc_get_gpr(vcpu, 9);
 548         bool is_load = !!gp_to;
 549         long rc;
 550
 551         if (gp_to && gp_from) /* One must be NULL to determine the direction */
 552                 return H_PARAMETER;
 553
 554         if (eaddr & (0xFFFUL << 52))
 555                 return H_PARAMETER;
 556
 557         buf = kzalloc(n, GFP_KERNEL);
 558         if (!buf)
 559                 return H_NO_MEM;
 560
 561         gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false);
 562         if (!gp) {
 563                 rc = H_PARAMETER;
 564                 goto out_free;
 565         }
 566
 567         mutex_lock(&gp->tlb_lock);
 568
 569         if (is_load) {
 570                 /* Load from the nested guest into our buffer */
 571                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 572                                                      eaddr, buf, NULL, n);
 573                 if (rc)
 574                         goto not_found;
 575
 576                 /* Write what was loaded into our buffer back to the L1 guest */
 577                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 578                 rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n);
 579                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 580                 if (rc)
 581                         goto not_found;
 582         } else {
 583                 /* Load the data to be stored from the L1 guest into our buf */
 584                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 585                 rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n);
 586                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 587                 if (rc)
 588                         goto not_found;
 589
 590                 /* Store from our buffer into the nested guest */
 591                 rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid,
 592                                                      eaddr, NULL, buf, n);
 593                 if (rc)
 594                         goto not_found;
 595         }
 596
 597 out_unlock:
 598         mutex_unlock(&gp->tlb_lock);
 599         kvmhv_put_nested(gp);
 600 out_free:
 601         kfree(buf);
 602         return rc;
 603 not_found:
 604         rc = H_NOT_FOUND;
 605         goto out_unlock;
 606 }
 607
 608 /*
 609  * Reload the partition table entry for a guest.
 610  * Caller must hold gp->tlb_lock.
 611  */
 612 static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp)
 613 {
 614         int ret;
 615         struct patb_entry ptbl_entry;
 616         unsigned long ptbl_addr;
 617         struct kvm *kvm = gp->l1_host;
 618
 619         ret = -EFAULT;
 620         ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4);
 621         if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 8))) {
 622                 int srcu_idx = srcu_read_lock(&kvm->srcu);
 623                 ret = kvm_read_guest(kvm, ptbl_addr,
 624                                      &ptbl_entry, sizeof(ptbl_entry));
 625                 srcu_read_unlock(&kvm->srcu, srcu_idx);
 626         }
 627         if (ret) {
 628                 gp->l1_gr_to_hr = 0;
 629                 gp->process_table = 0;
 630         } else {
 631                 gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0);
 632                 gp->process_table = be64_to_cpu(ptbl_entry.patb1);
 633         }
 634         kvmhv_set_nested_ptbl(gp);
 635 }
 636
 637 static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
 638 {
 639         struct kvm_nested_guest *gp;
 640         long shadow_lpid;
 641
 642         gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 643         if (!gp)
 644                 return NULL;
 645         gp->l1_host = kvm;
 646         gp->l1_lpid = lpid;
 647         mutex_init(&gp->tlb_lock);
 648         gp->shadow_pgtable = pgd_alloc(kvm->mm);
 649         if (!gp->shadow_pgtable)
 650                 goto out_free;
 651         shadow_lpid = kvmppc_alloc_lpid();
 652         if (shadow_lpid < 0)
 653                 goto out_free2;
 654         gp->shadow_lpid = shadow_lpid;
 655         gp->radix = 1;
 656
 657         memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu));
 658
 659         return gp;
 660
 661  out_free2:
 662         pgd_free(kvm->mm, gp->shadow_pgtable);
 663  out_free:
 664         kfree(gp);
 665         return NULL;
 666 }
 667
 668 /*
 669  * Free up any resources allocated for a nested guest.
 670  */
 671 static void kvmhv_release_nested(struct kvm_nested_guest *gp)
 672 {
 673         struct kvm *kvm = gp->l1_host;
 674
 675         if (gp->shadow_pgtable) {
 676                 /*
 677                  * No vcpu is using this struct and no call to
 678                  * kvmhv_get_nested can find this struct,
 679                  * so we don't need to hold kvm->mmu_lock.
 680                  */
 681                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
 682                                           gp->shadow_lpid);
 683                 pgd_free(kvm->mm, gp->shadow_pgtable);
 684         }
 685         kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0);
 686         kvmppc_free_lpid(gp->shadow_lpid);
 687         kfree(gp);
 688 }
 689
 690 static void kvmhv_remove_nested(struct kvm_nested_guest *gp)
 691 {
 692         struct kvm *kvm = gp->l1_host;
 693         int lpid = gp->l1_lpid;
 694         long ref;
 695
 696         spin_lock(&kvm->mmu_lock);
 697         if (gp == kvm->arch.nested_guests[lpid]) {
 698                 kvm->arch.nested_guests[lpid] = NULL;
 699                 if (lpid == kvm->arch.max_nested_lpid) {
 700                         while (--lpid >= 0 && !kvm->arch.nested_guests[lpid])
 701                                 ;
 702                         kvm->arch.max_nested_lpid = lpid;
 703                 }
 704                 --gp->refcnt;
 705         }
 706         ref = gp->refcnt;
 707         spin_unlock(&kvm->mmu_lock);
 708         if (ref == 0)
 709                 kvmhv_release_nested(gp);
 710 }
 711
 712 /*
 713  * Free up all nested resources allocated for this guest.
 714  * This is called with no vcpus of the guest running, when
 715  * switching the guest to HPT mode or when destroying the
 716  * guest.
 717  */
 718 void kvmhv_release_all_nested(struct kvm *kvm)
 719 {
 720         int i;
 721         struct kvm_nested_guest *gp;
 722         struct kvm_nested_guest *freelist = NULL;
 723         struct kvm_memory_slot *memslot;
 724         int srcu_idx;
 725
 726         spin_lock(&kvm->mmu_lock);
 727         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
 728                 gp = kvm->arch.nested_guests[i];
 729                 if (!gp)
 730                         continue;
 731                 kvm->arch.nested_guests[i] = NULL;
 732                 if (--gp->refcnt == 0) {
 733                         gp->next = freelist;
 734                         freelist = gp;
 735                 }
 736         }
 737         kvm->arch.max_nested_lpid = -1;
 738         spin_unlock(&kvm->mmu_lock);
 739         while ((gp = freelist) != NULL) {
 740                 freelist = gp->next;
 741                 kvmhv_release_nested(gp);
 742         }
 743
 744         srcu_idx = srcu_read_lock(&kvm->srcu);
 745         kvm_for_each_memslot(memslot, kvm_memslots(kvm))
 746                 kvmhv_free_memslot_nest_rmap(memslot);
 747         srcu_read_unlock(&kvm->srcu, srcu_idx);
 748 }
 749
 750 /* caller must hold gp->tlb_lock */
 751 static void kvmhv_flush_nested(struct kvm_nested_guest *gp)
 752 {
 753         struct kvm *kvm = gp->l1_host;
 754
 755         spin_lock(&kvm->mmu_lock);
 756         kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid);
 757         spin_unlock(&kvm->mmu_lock);
 758         kvmhv_flush_lpid(gp->shadow_lpid);
 759         kvmhv_update_ptbl_cache(gp);
 760         if (gp->l1_gr_to_hr == 0)
 761                 kvmhv_remove_nested(gp);
 762 }
 763
 764 struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid,
 765                                           bool create)
 766 {
 767         struct kvm_nested_guest *gp, *newgp;
 768
 769         if (l1_lpid >= KVM_MAX_NESTED_GUESTS ||
 770             l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4)))
 771                 return NULL;
 772
 773         spin_lock(&kvm->mmu_lock);
 774         gp = kvm->arch.nested_guests[l1_lpid];
 775         if (gp)
 776                 ++gp->refcnt;
 777         spin_unlock(&kvm->mmu_lock);
 778
 779         if (gp || !create)
 780                 return gp;
 781
 782         newgp = kvmhv_alloc_nested(kvm, l1_lpid);
 783         if (!newgp)
 784                 return NULL;
 785         spin_lock(&kvm->mmu_lock);
 786         if (kvm->arch.nested_guests[l1_lpid]) {
 787                 /* someone else beat us to it */
 788                 gp = kvm->arch.nested_guests[l1_lpid];
 789         } else {
 790                 kvm->arch.nested_guests[l1_lpid] = newgp;
 791                 ++newgp->refcnt;
 792                 gp = newgp;
 793                 newgp = NULL;
 794                 if (l1_lpid > kvm->arch.max_nested_lpid)
 795                         kvm->arch.max_nested_lpid = l1_lpid;
 796         }
 797         ++gp->refcnt;
 798         spin_unlock(&kvm->mmu_lock);
 799
 800         if (newgp)
 801                 kvmhv_release_nested(newgp);
 802
 803         return gp;
 804 }
 805
 806 void kvmhv_put_nested(struct kvm_nested_guest *gp)
 807 {
 808         struct kvm *kvm = gp->l1_host;
 809         long ref;
 810
 811         spin_lock(&kvm->mmu_lock);
 812         ref = --gp->refcnt;
 813         spin_unlock(&kvm->mmu_lock);
 814         if (ref == 0)
 815                 kvmhv_release_nested(gp);
 816 }
 817
 818 static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid)
 819 {
 820         if (lpid > kvm->arch.max_nested_lpid)
 821                 return NULL;
 822         return kvm->arch.nested_guests[lpid];
 823 }
 824
 825 pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid,
 826                                  unsigned long ea, unsigned *hshift)
 827 {
 828         struct kvm_nested_guest *gp;
 829         pte_t *pte;
 830
 831         gp = kvmhv_find_nested(kvm, lpid);
 832         if (!gp)
 833                 return NULL;
 834
 835         VM_WARN(!spin_is_locked(&kvm->mmu_lock),
 836                 "%s called with kvm mmu_lock not held \n", __func__);
 837         pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift);
 838
 839         return pte;
 840 }
 841
 842 static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2)
 843 {
 844         return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK |
 845                                        RMAP_NESTED_GPA_MASK));
 846 }
 847
 848 void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp,
 849                             struct rmap_nested **n_rmap)
 850 {
 851         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 852         struct rmap_nested *cursor;
 853         u64 rmap, new_rmap = (*n_rmap)->rmap;
 854
 855         /* Are there any existing entries? */
 856         if (!(*rmapp)) {
 857                 /* No -> use the rmap as a single entry */
 858                 *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY;
 859                 return;
 860         }
 861
 862         /* Do any entries match what we're trying to insert? */
 863         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 864                 if (kvmhv_n_rmap_is_equal(rmap, new_rmap))
 865                         return;
 866         }
 867
 868         /* Do we need to create a list or just add the new entry? */
 869         rmap = *rmapp;
 870         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 871                 *rmapp = 0UL;
 872         llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp);
 873         if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */
 874                 (*n_rmap)->list.next = (struct llist_node *) rmap;
 875
 876         /* Set NULL so not freed by caller */
 877         *n_rmap = NULL;
 878 }
 879
 880 static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap,
 881                                       unsigned long clr, unsigned long set,
 882                                       unsigned long hpa, unsigned long mask)
 883 {
 884         unsigned long gpa;
 885         unsigned int shift, lpid;
 886         pte_t *ptep;
 887
 888         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 889         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 890
 891         /* Find the pte */
 892         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 893         /*
 894          * If the pte is present and the pfn is still the same, update the pte.
 895          * If the pfn has changed then this is a stale rmap entry, the nested
 896          * gpa actually points somewhere else now, and there is nothing to do.
 897          * XXX A future optimisation would be to remove the rmap entry here.
 898          */
 899         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) {
 900                 __radix_pte_update(ptep, clr, set);
 901                 kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid);
 902         }
 903 }
 904
 905 /*
 906  * For a given list of rmap entries, update the rc bits in all ptes in shadow
 907  * page tables for nested guests which are referenced by the rmap list.
 908  */
 909 void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp,
 910                                     unsigned long clr, unsigned long set,
 911                                     unsigned long hpa, unsigned long nbytes)
 912 {
 913         struct llist_node *entry = ((struct llist_head *) rmapp)->first;
 914         struct rmap_nested *cursor;
 915         unsigned long rmap, mask;
 916
 917         if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED))
 918                 return;
 919
 920         mask = PTE_RPN_MASK & ~(nbytes - 1);
 921         hpa &= mask;
 922
 923         for_each_nest_rmap_safe(cursor, entry, &rmap)
 924                 kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask);
 925 }
 926
 927 static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap,
 928                                    unsigned long hpa, unsigned long mask)
 929 {
 930         struct kvm_nested_guest *gp;
 931         unsigned long gpa;
 932         unsigned int shift, lpid;
 933         pte_t *ptep;
 934
 935         gpa = n_rmap & RMAP_NESTED_GPA_MASK;
 936         lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT;
 937         gp = kvmhv_find_nested(kvm, lpid);
 938         if (!gp)
 939                 return;
 940
 941         /* Find and invalidate the pte */
 942         ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift);
 943         /* Don't spuriously invalidate ptes if the pfn has changed */
 944         if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa))
 945                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
 946 }
 947
 948 static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp,
 949                                         unsigned long hpa, unsigned long mask)
 950 {
 951         struct llist_node *entry = llist_del_all((struct llist_head *) rmapp);
 952         struct rmap_nested *cursor;
 953         unsigned long rmap;
 954
 955         for_each_nest_rmap_safe(cursor, entry, &rmap) {
 956                 kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask);
 957                 kfree(cursor);
 958         }
 959 }
 960
 961 /* called with kvm->mmu_lock held */
 962 void kvmhv_remove_nest_rmap_range(struct kvm *kvm,
 963                                   const struct kvm_memory_slot *memslot,
 964                                   unsigned long gpa, unsigned long hpa,
 965                                   unsigned long nbytes)
 966 {
 967         unsigned long gfn, end_gfn;
 968         unsigned long addr_mask;
 969
 970         if (!memslot)
 971                 return;
 972         gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn;
 973         end_gfn = gfn + (nbytes >> PAGE_SHIFT);
 974
 975         addr_mask = PTE_RPN_MASK & ~(nbytes - 1);
 976         hpa &= addr_mask;
 977
 978         for (; gfn < end_gfn; gfn++) {
 979                 unsigned long *rmap = &memslot->arch.rmap[gfn];
 980                 kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask);
 981         }
 982 }
 983
 984 static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free)
 985 {
 986         unsigned long page;
 987
 988         for (page = 0; page < free->npages; page++) {
 989                 unsigned long rmap, *rmapp = &free->arch.rmap[page];
 990                 struct rmap_nested *cursor;
 991                 struct llist_node *entry;
 992
 993                 entry = llist_del_all((struct llist_head *) rmapp);
 994                 for_each_nest_rmap_safe(cursor, entry, &rmap)
 995                         kfree(cursor);
 996         }
 997 }
 998
 999 static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu,
1000                                         struct kvm_nested_guest *gp,
1001                                         long gpa, int *shift_ret)
1002 {
1003         struct kvm *kvm = vcpu->kvm;
1004         bool ret = false;
1005         pte_t *ptep;
1006         int shift;
1007
1008         spin_lock(&kvm->mmu_lock);
1009         ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift);
1010         if (!shift)
1011                 shift = PAGE_SHIFT;
1012         if (ptep && pte_present(*ptep)) {
1013                 kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid);
1014                 ret = true;
1015         }
1016         spin_unlock(&kvm->mmu_lock);
1017
1018         if (shift_ret)
1019                 *shift_ret = shift;
1020         return ret;
1021 }
1022
1023 static inline int get_ric(unsigned int instr)
1024 {
1025         return (instr >> 18) & 0x3;
1026 }
1027
1028 static inline int get_prs(unsigned int instr)
1029 {
1030         return (instr >> 17) & 0x1;
1031 }
1032
1033 static inline int get_r(unsigned int instr)
1034 {
1035         return (instr >> 16) & 0x1;
1036 }
1037
1038 static inline int get_lpid(unsigned long r_val)
1039 {
1040         return r_val & 0xffffffff;
1041 }
1042
1043 static inline int get_is(unsigned long r_val)
1044 {
1045         return (r_val >> 10) & 0x3;
1046 }
1047
1048 static inline int get_ap(unsigned long r_val)
1049 {
1050         return (r_val >> 5) & 0x7;
1051 }
1052
1053 static inline long get_epn(unsigned long r_val)
1054 {
1055         return r_val >> 12;
1056 }
1057
1058 static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid,
1059                                         int ap, long epn)
1060 {
1061         struct kvm *kvm = vcpu->kvm;
1062         struct kvm_nested_guest *gp;
1063         long npages;
1064         int shift, shadow_shift;
1065         unsigned long addr;
1066
1067         shift = ap_to_shift(ap);
1068         addr = epn << 12;
1069         if (shift < 0)
1070                 /* Invalid ap encoding */
1071                 return -EINVAL;
1072
1073         addr &= ~((1UL << shift) - 1);
1074         npages = 1UL << (shift - PAGE_SHIFT);
1075
1076         gp = kvmhv_get_nested(kvm, lpid, false);
1077         if (!gp) /* No such guest -> nothing to do */
1078                 return 0;
1079         mutex_lock(&gp->tlb_lock);
1080
1081         /* There may be more than one host page backing this single guest pte */
1082         do {
1083                 kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift);
1084
1085                 npages -= 1UL << (shadow_shift - PAGE_SHIFT);
1086                 addr += 1UL << shadow_shift;
1087         } while (npages > 0);
1088
1089         mutex_unlock(&gp->tlb_lock);
1090         kvmhv_put_nested(gp);
1091         return 0;
1092 }
1093
1094 static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu,
1095                                      struct kvm_nested_guest *gp, int ric)
1096 {
1097         struct kvm *kvm = vcpu->kvm;
1098
1099         mutex_lock(&gp->tlb_lock);
1100         switch (ric) {
1101         case 0:
1102                 /* Invalidate TLB */
1103                 spin_lock(&kvm->mmu_lock);
1104                 kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable,
1105                                           gp->shadow_lpid);
1106                 kvmhv_flush_lpid(gp->shadow_lpid);
1107                 spin_unlock(&kvm->mmu_lock);
1108                 break;
1109         case 1:
1110                 /*
1111                  * Invalidate PWC
1112                  * We don't cache this -> nothing to do
1113                  */
1114                 break;
1115         case 2:
1116                 /* Invalidate TLB, PWC and caching of partition table entries */
1117                 kvmhv_flush_nested(gp);
1118                 break;
1119         default:
1120                 break;
1121         }
1122         mutex_unlock(&gp->tlb_lock);
1123 }
1124
1125 static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric)
1126 {
1127         struct kvm *kvm = vcpu->kvm;
1128         struct kvm_nested_guest *gp;
1129         int i;
1130
1131         spin_lock(&kvm->mmu_lock);
1132         for (i = 0; i <= kvm->arch.max_nested_lpid; i++) {
1133                 gp = kvm->arch.nested_guests[i];
1134                 if (gp) {
1135                         spin_unlock(&kvm->mmu_lock);
1136                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1137                         spin_lock(&kvm->mmu_lock);
1138                 }
1139         }
1140         spin_unlock(&kvm->mmu_lock);
1141 }
1142
1143 static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr,
1144                                     unsigned long rsval, unsigned long rbval)
1145 {
1146         struct kvm *kvm = vcpu->kvm;
1147         struct kvm_nested_guest *gp;
1148         int r, ric, prs, is, ap;
1149         int lpid;
1150         long epn;
1151         int ret = 0;
1152
1153         ric = get_ric(instr);
1154         prs = get_prs(instr);
1155         r = get_r(instr);
1156         lpid = get_lpid(rsval);
1157         is = get_is(rbval);
1158
1159         /*
1160          * These cases are invalid and are not handled:
1161          * r   != 1 -> Only radix supported
1162          * prs == 1 -> Not HV privileged
1163          * ric == 3 -> No cluster bombs for radix
1164          * is  == 1 -> Partition scoped translations not associated with pid
1165          * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA
1166          */
1167         if ((!r) || (prs) || (ric == 3) || (is == 1) ||
1168             ((!is) && (ric == 1 || ric == 2)))
1169                 return -EINVAL;
1170
1171         switch (is) {
1172         case 0:
1173                 /*
1174                  * We know ric == 0
1175                  * Invalidate TLB for a given target address
1176                  */
1177                 epn = get_epn(rbval);
1178                 ap = get_ap(rbval);
1179                 ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn);
1180                 break;
1181         case 2:
1182                 /* Invalidate matching LPID */
1183                 gp = kvmhv_get_nested(kvm, lpid, false);
1184                 if (gp) {
1185                         kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1186                         kvmhv_put_nested(gp);
1187                 }
1188                 break;
1189         case 3:
1190                 /* Invalidate ALL LPIDs */
1191                 kvmhv_emulate_tlbie_all_lpid(vcpu, ric);
1192                 break;
1193         default:
1194                 ret = -EINVAL;
1195                 break;
1196         }
1197
1198         return ret;
1199 }
1200
1201 /*
1202  * This handles the H_TLB_INVALIDATE hcall.
1203  * Parameters are (r4) tlbie instruction code, (r5) rS contents,
1204  * (r6) rB contents.
1205  */
1206 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu)
1207 {
1208         int ret;
1209
1210         ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4),
1211                         kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6));
1212         if (ret)
1213                 return H_PARAMETER;
1214         return H_SUCCESS;
1215 }
1216
1217 static long do_tlb_invalidate_nested_all(struct kvm_vcpu *vcpu,
1218                                          unsigned long lpid, unsigned long ric)
1219 {
1220         struct kvm *kvm = vcpu->kvm;
1221         struct kvm_nested_guest *gp;
1222
1223         gp = kvmhv_get_nested(kvm, lpid, false);
1224         if (gp) {
1225                 kvmhv_emulate_tlbie_lpid(vcpu, gp, ric);
1226                 kvmhv_put_nested(gp);
1227         }
1228         return H_SUCCESS;
1229 }
1230
1231 /*
1232  * Number of pages above which we invalidate the entire LPID rather than
1233  * flush individual pages.
1234  */
1235 static unsigned long tlb_range_flush_page_ceiling __read_mostly = 33;
1236
1237 static long do_tlb_invalidate_nested_tlb(struct kvm_vcpu *vcpu,
1238                                          unsigned long lpid,
1239                                          unsigned long pg_sizes,
1240                                          unsigned long start,
1241                                          unsigned long end)
1242 {
1243         int ret = H_P4;
1244         unsigned long addr, nr_pages;
1245         struct mmu_psize_def *def;
1246         unsigned long psize, ap, page_size;
1247         bool flush_lpid;
1248
1249         for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
1250                 def = &mmu_psize_defs[psize];
1251                 if (!(pg_sizes & def->h_rpt_pgsize))
1252                         continue;
1253
1254                 nr_pages = (end - start) >> def->shift;
1255                 flush_lpid = nr_pages > tlb_range_flush_page_ceiling;
1256                 if (flush_lpid)
1257                         return do_tlb_invalidate_nested_all(vcpu, lpid,
1258                                                         RIC_FLUSH_TLB);
1259                 addr = start;
1260                 ap = mmu_get_ap(psize);
1261                 page_size = 1UL << def->shift;
1262                 do {
1263                         ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap,
1264                                                    get_epn(addr));
1265                         if (ret)
1266                                 return H_P4;
1267                         addr += page_size;
1268                 } while (addr < end);
1269         }
1270         return ret;
1271 }
1272
1273 /*
1274  * Performs partition-scoped invalidations for nested guests
1275  * as part of H_RPT_INVALIDATE hcall.
1276  */
1277 long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
1278                              unsigned long type, unsigned long pg_sizes,
1279                              unsigned long start, unsigned long end)
1280 {
1281         /*
1282          * If L2 lpid isn't valid, we need to return H_PARAMETER.
1283          *
1284          * However, nested KVM issues a L2 lpid flush call when creating
1285          * partition table entries for L2. This happens even before the
1286          * corresponding shadow lpid is created in HV which happens in
1287          * H_ENTER_NESTED call. Since we can't differentiate this case from
1288          * the invalid case, we ignore such flush requests and return success.
1289          */
1290         if (!kvmhv_find_nested(vcpu->kvm, lpid))
1291                 return H_SUCCESS;
1292
1293         /*
1294          * A flush all request can be handled by a full lpid flush only.
1295          */
1296         if ((type & H_RPTI_TYPE_NESTED_ALL) == H_RPTI_TYPE_NESTED_ALL)
1297                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_ALL);
1298
1299         /*
1300          * We don't need to handle a PWC flush like process table here,
1301          * because intermediate partition scoped table in nested guest doesn't
1302          * really have PWC. Only level we have PWC is in L0 and for nested
1303          * invalidate at L0 we always do kvm_flush_lpid() which does
1304          * radix__flush_all_lpid(). For range invalidate at any level, we
1305          * are not removing the higher level page tables and hence there is
1306          * no PWC invalidate needed.
1307          *
1308          * if (type & H_RPTI_TYPE_PWC) {
1309          *      ret = do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_PWC);
1310          *      if (ret)
1311          *              return H_P4;
1312          * }
1313          */
1314
1315         if (start == 0 && end == -1)
1316                 return do_tlb_invalidate_nested_all(vcpu, lpid, RIC_FLUSH_TLB);
1317
1318         if (type & H_RPTI_TYPE_TLB)
1319                 return do_tlb_invalidate_nested_tlb(vcpu, lpid, pg_sizes,
1320                                                     start, end);
1321         return H_SUCCESS;
1322 }
1323
1324 /* Used to convert a nested guest real address to a L1 guest real address */
1325 static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu,
1326                                        struct kvm_nested_guest *gp,
1327                                        unsigned long n_gpa, unsigned long dsisr,
1328                                        struct kvmppc_pte *gpte_p)
1329 {
1330         u64 fault_addr, flags = dsisr & DSISR_ISSTORE;
1331         int ret;
1332
1333         ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr,
1334                                          &fault_addr);
1335
1336         if (ret) {
1337                 /* We didn't find a pte */
1338                 if (ret == -EINVAL) {
1339                         /* Unsupported mmu config */
1340                         flags |= DSISR_UNSUPP_MMU;
1341                 } else if (ret == -ENOENT) {
1342                         /* No translation found */
1343                         flags |= DSISR_NOHPTE;
1344                 } else if (ret == -EFAULT) {
1345                         /* Couldn't access L1 real address */
1346                         flags |= DSISR_PRTABLE_FAULT;
1347                         vcpu->arch.fault_gpa = fault_addr;
1348                 } else {
1349                         /* Unknown error */
1350                         return ret;
1351                 }
1352                 goto forward_to_l1;
1353         } else {
1354                 /* We found a pte -> check permissions */
1355                 if (dsisr & DSISR_ISSTORE) {
1356                         /* Can we write? */
1357                         if (!gpte_p->may_write) {
1358                                 flags |= DSISR_PROTFAULT;
1359                                 goto forward_to_l1;
1360                         }
1361                 } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1362                         /* Can we execute? */
1363                         if (!gpte_p->may_execute) {
1364                                 flags |= SRR1_ISI_N_G_OR_CIP;
1365                                 goto forward_to_l1;
1366                         }
1367                 } else {
1368                         /* Can we read? */
1369                         if (!gpte_p->may_read && !gpte_p->may_write) {
1370                                 flags |= DSISR_PROTFAULT;
1371                                 goto forward_to_l1;
1372                         }
1373                 }
1374         }
1375
1376         return 0;
1377
1378 forward_to_l1:
1379         vcpu->arch.fault_dsisr = flags;
1380         if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) {
1381                 vcpu->arch.shregs.msr &= SRR1_MSR_BITS;
1382                 vcpu->arch.shregs.msr |= flags;
1383         }
1384         return RESUME_HOST;
1385 }
1386
1387 static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu,
1388                                        struct kvm_nested_guest *gp,
1389                                        unsigned long n_gpa,
1390                                        struct kvmppc_pte gpte,
1391                                        unsigned long dsisr)
1392 {
1393         struct kvm *kvm = vcpu->kvm;
1394         bool writing = !!(dsisr & DSISR_ISSTORE);
1395         u64 pgflags;
1396         long ret;
1397
1398         /* Are the rc bits set in the L1 partition scoped pte? */
1399         pgflags = _PAGE_ACCESSED;
1400         if (writing)
1401                 pgflags |= _PAGE_DIRTY;
1402         if (pgflags & ~gpte.rc)
1403                 return RESUME_HOST;
1404
1405         spin_lock(&kvm->mmu_lock);
1406         /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */
1407         ret = kvmppc_hv_handle_set_rc(kvm, false, writing,
1408                                       gpte.raddr, kvm->arch.lpid);
1409         if (!ret) {
1410                 ret = -EINVAL;
1411                 goto out_unlock;
1412         }
1413
1414         /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */
1415         ret = kvmppc_hv_handle_set_rc(kvm, true, writing,
1416                                       n_gpa, gp->l1_lpid);
1417         if (!ret)
1418                 ret = -EINVAL;
1419         else
1420                 ret = 0;
1421
1422 out_unlock:
1423         spin_unlock(&kvm->mmu_lock);
1424         return ret;
1425 }
1426
1427 static inline int kvmppc_radix_level_to_shift(int level)
1428 {
1429         switch (level) {
1430         case 2:
1431                 return PUD_SHIFT;
1432         case 1:
1433                 return PMD_SHIFT;
1434         default:
1435                 return PAGE_SHIFT;
1436         }
1437 }
1438
1439 static inline int kvmppc_radix_shift_to_level(int shift)
1440 {
1441         if (shift == PUD_SHIFT)
1442                 return 2;
1443         if (shift == PMD_SHIFT)
1444                 return 1;
1445         if (shift == PAGE_SHIFT)
1446                 return 0;
1447         WARN_ON_ONCE(1);
1448         return 0;
1449 }
1450
1451 /* called with gp->tlb_lock held */
1452 static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu,
1453                                           struct kvm_nested_guest *gp)
1454 {
1455         struct kvm *kvm = vcpu->kvm;
1456         struct kvm_memory_slot *memslot;
1457         struct rmap_nested *n_rmap;
1458         struct kvmppc_pte gpte;
1459         pte_t pte, *pte_p;
1460         unsigned long mmu_seq;
1461         unsigned long dsisr = vcpu->arch.fault_dsisr;
1462         unsigned long ea = vcpu->arch.fault_dar;
1463         unsigned long *rmapp;
1464         unsigned long n_gpa, gpa, gfn, perm = 0UL;
1465         unsigned int shift, l1_shift, level;
1466         bool writing = !!(dsisr & DSISR_ISSTORE);
1467         bool kvm_ro = false;
1468         long int ret;
1469
1470         if (!gp->l1_gr_to_hr) {
1471                 kvmhv_update_ptbl_cache(gp);
1472                 if (!gp->l1_gr_to_hr)
1473                         return RESUME_HOST;
1474         }
1475
1476         /* Convert the nested guest real address into a L1 guest real address */
1477
1478         n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL;
1479         if (!(dsisr & DSISR_PRTABLE_FAULT))
1480                 n_gpa |= ea & 0xFFF;
1481         ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte);
1482
1483         /*
1484          * If the hardware found a translation but we don't now have a usable
1485          * translation in the l1 partition-scoped tree, remove the shadow pte
1486          * and let the guest retry.
1487          */
1488         if (ret == RESUME_HOST &&
1489             (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G |
1490                       DSISR_BAD_COPYPASTE)))
1491                 goto inval;
1492         if (ret)
1493                 return ret;
1494
1495         /* Failed to set the reference/change bits */
1496         if (dsisr & DSISR_SET_RC) {
1497                 ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr);
1498                 if (ret == RESUME_HOST)
1499                         return ret;
1500                 if (ret)
1501                         goto inval;
1502                 dsisr &= ~DSISR_SET_RC;
1503                 if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
1504                                DSISR_PROTFAULT)))
1505                         return RESUME_GUEST;
1506         }
1507
1508         /*
1509          * We took an HISI or HDSI while we were running a nested guest which
1510          * means we have no partition scoped translation for that. This means
1511          * we need to insert a pte for the mapping into our shadow_pgtable.
1512          */
1513
1514         l1_shift = gpte.page_shift;
1515         if (l1_shift < PAGE_SHIFT) {
1516                 /* We don't support l1 using a page size smaller than our own */
1517                 pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n",
1518                         l1_shift, PAGE_SHIFT);
1519                 return -EINVAL;
1520         }
1521         gpa = gpte.raddr;
1522         gfn = gpa >> PAGE_SHIFT;
1523
1524         /* 1. Get the corresponding host memslot */
1525
1526         memslot = gfn_to_memslot(kvm, gfn);
1527         if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
1528                 if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) {
1529                         /* unusual error -> reflect to the guest as a DSI */
1530                         kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
1531                         return RESUME_GUEST;
1532                 }
1533
1534                 /* passthrough of emulated MMIO case */
1535                 return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing);
1536         }
1537         if (memslot->flags & KVM_MEM_READONLY) {
1538                 if (writing) {
1539                         /* Give the guest a DSI */
1540                         kvmppc_core_queue_data_storage(vcpu, ea,
1541                                         DSISR_ISSTORE | DSISR_PROTFAULT);
1542                         return RESUME_GUEST;
1543                 }
1544                 kvm_ro = true;
1545         }
1546
1547         /* 2. Find the host pte for this L1 guest real address */
1548
1549         /* Used to check for invalidations in progress */
1550         mmu_seq = kvm->mmu_notifier_seq;
1551         smp_rmb();
1552
1553         /* See if can find translation in our partition scoped tables for L1 */
1554         pte = __pte(0);
1555         spin_lock(&kvm->mmu_lock);
1556         pte_p = find_kvm_secondary_pte(kvm, gpa, &shift);
1557         if (!shift)
1558                 shift = PAGE_SHIFT;
1559         if (pte_p)
1560                 pte = *pte_p;
1561         spin_unlock(&kvm->mmu_lock);
1562
1563         if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) {
1564                 /* No suitable pte found -> try to insert a mapping */
1565                 ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot,
1566                                         writing, kvm_ro, &pte, &level);
1567                 if (ret == -EAGAIN)
1568                         return RESUME_GUEST;
1569                 else if (ret)
1570                         return ret;
1571                 shift = kvmppc_radix_level_to_shift(level);
1572         }
1573         /* Align gfn to the start of the page */
1574         gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT;
1575
1576         /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */
1577
1578         /* The permissions is the combination of the host and l1 guest ptes */
1579         perm |= gpte.may_read ? 0UL : _PAGE_READ;
1580         perm |= gpte.may_write ? 0UL : _PAGE_WRITE;
1581         perm |= gpte.may_execute ? 0UL : _PAGE_EXEC;
1582         /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */
1583         perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED;
1584         perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY;
1585         pte = __pte(pte_val(pte) & ~perm);
1586
1587         /* What size pte can we insert? */
1588         if (shift > l1_shift) {
1589                 u64 mask;
1590                 unsigned int actual_shift = PAGE_SHIFT;
1591                 if (PMD_SHIFT < l1_shift)
1592                         actual_shift = PMD_SHIFT;
1593                 mask = (1UL << shift) - (1UL << actual_shift);
1594                 pte = __pte(pte_val(pte) | (gpa & mask));
1595                 shift = actual_shift;
1596         }
1597         level = kvmppc_radix_shift_to_level(shift);
1598         n_gpa &= ~((1UL << shift) - 1);
1599
1600         /* 4. Insert the pte into our shadow_pgtable */
1601
1602         n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL);
1603         if (!n_rmap)
1604                 return RESUME_GUEST; /* Let the guest try again */
1605         n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) |
1606                 (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT);
1607         rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn];
1608         ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level,
1609                                 mmu_seq, gp->shadow_lpid, rmapp, &n_rmap);
1610         kfree(n_rmap);
1611         if (ret == -EAGAIN)
1612                 ret = RESUME_GUEST;     /* Let the guest try again */
1613
1614         return ret;
1615
1616  inval:
1617         kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL);
1618         return RESUME_GUEST;
1619 }
1620
1621 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu)
1622 {
1623         struct kvm_nested_guest *gp = vcpu->arch.nested;
1624         long int ret;
1625
1626         mutex_lock(&gp->tlb_lock);
1627         ret = __kvmhv_nested_page_fault(vcpu, gp);
1628         mutex_unlock(&gp->tlb_lock);
1629         return ret;
1630 }
1631
1632 int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid)
1633 {
1634         int ret = -1;
1635
1636         spin_lock(&kvm->mmu_lock);
1637         while (++lpid <= kvm->arch.max_nested_lpid) {
1638                 if (kvm->arch.nested_guests[lpid]) {
1639                         ret = lpid;
1640                         break;
1641                 }
1642         }
1643         spin_unlock(&kvm->mmu_lock);
1644         return ret;
1645 }