arch/s390/kvm/vsie.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * kvm nested virtualization support for s390x
   4  *
   5  * Copyright IBM Corp. 2016
   6  *
   7  *    Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com>
   8  */
   9 #include <linux/vmalloc.h>
  10 #include <linux/kvm_host.h>
  11 #include <linux/bug.h>
  12 #include <linux/list.h>
  13 #include <linux/bitmap.h>
  14 #include <linux/sched/signal.h>
  15
  16 #include <asm/gmap.h>
  17 #include <asm/mmu_context.h>
  18 #include <asm/sclp.h>
  19 #include <asm/nmi.h>
  20 #include <asm/dis.h>
  21 #include "kvm-s390.h"
  22 #include "gaccess.h"
  23
  24 struct vsie_page {
  25         struct kvm_s390_sie_block scb_s;        /* 0x0000 */
  26         /*
  27          * the backup info for machine check. ensure it's at
  28          * the same offset as that in struct sie_page!
  29          */
  30         struct mcck_volatile_info mcck_info;    /* 0x0200 */
  31         /*
  32          * The pinned original scb. Be aware that other VCPUs can modify
  33          * it while we read from it. Values that are used for conditions or
  34          * are reused conditionally, should be accessed via READ_ONCE.
  35          */
  36         struct kvm_s390_sie_block *scb_o;       /* 0x0218 */
  37         /* the shadow gmap in use by the vsie_page */
  38         struct gmap *gmap;                      /* 0x0220 */
  39         /* address of the last reported fault to guest2 */
  40         unsigned long fault_addr;               /* 0x0228 */
  41         /* calculated guest addresses of satellite control blocks */
  42         gpa_t sca_gpa;                          /* 0x0230 */
  43         gpa_t itdba_gpa;                        /* 0x0238 */
  44         gpa_t gvrd_gpa;                         /* 0x0240 */
  45         gpa_t riccbd_gpa;                       /* 0x0248 */
  46         gpa_t sdnx_gpa;                         /* 0x0250 */
  47         __u8 reserved[0x0700 - 0x0258];         /* 0x0258 */
  48         struct kvm_s390_crypto_cb crycb;        /* 0x0700 */
  49         __u8 fac[S390_ARCH_FAC_LIST_SIZE_BYTE]; /* 0x0800 */
  50 };
  51
  52 /* trigger a validity icpt for the given scb */
  53 static int set_validity_icpt(struct kvm_s390_sie_block *scb,
  54                              __u16 reason_code)
  55 {
  56         scb->ipa = 0x1000;
  57         scb->ipb = ((__u32) reason_code) << 16;
  58         scb->icptcode = ICPT_VALIDITY;
  59         return 1;
  60 }
  61
  62 /* mark the prefix as unmapped, this will block the VSIE */
  63 static void prefix_unmapped(struct vsie_page *vsie_page)
  64 {
  65         atomic_or(PROG_REQUEST, &vsie_page->scb_s.prog20);
  66 }
  67
  68 /* mark the prefix as unmapped and wait until the VSIE has been left */
  69 static void prefix_unmapped_sync(struct vsie_page *vsie_page)
  70 {
  71         prefix_unmapped(vsie_page);
  72         if (vsie_page->scb_s.prog0c & PROG_IN_SIE)
  73                 atomic_or(CPUSTAT_STOP_INT, &vsie_page->scb_s.cpuflags);
  74         while (vsie_page->scb_s.prog0c & PROG_IN_SIE)
  75                 cpu_relax();
  76 }
  77
  78 /* mark the prefix as mapped, this will allow the VSIE to run */
  79 static void prefix_mapped(struct vsie_page *vsie_page)
  80 {
  81         atomic_andnot(PROG_REQUEST, &vsie_page->scb_s.prog20);
  82 }
  83
  84 /* test if the prefix is mapped into the gmap shadow */
  85 static int prefix_is_mapped(struct vsie_page *vsie_page)
  86 {
  87         return !(atomic_read(&vsie_page->scb_s.prog20) & PROG_REQUEST);
  88 }
  89
  90 /* copy the updated intervention request bits into the shadow scb */
  91 static void update_intervention_requests(struct vsie_page *vsie_page)
  92 {
  93         const int bits = CPUSTAT_STOP_INT | CPUSTAT_IO_INT | CPUSTAT_EXT_INT;
  94         int cpuflags;
  95
  96         cpuflags = atomic_read(&vsie_page->scb_o->cpuflags);
  97         atomic_andnot(bits, &vsie_page->scb_s.cpuflags);
  98         atomic_or(cpuflags & bits, &vsie_page->scb_s.cpuflags);
  99 }
 100
 101 /* shadow (filter and validate) the cpuflags  */
 102 static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 103 {
 104         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 105         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 106         int newflags, cpuflags = atomic_read(&scb_o->cpuflags);
 107
 108         /* we don't allow ESA/390 guests */
 109         if (!(cpuflags & CPUSTAT_ZARCH))
 110                 return set_validity_icpt(scb_s, 0x0001U);
 111
 112         if (cpuflags & (CPUSTAT_RRF | CPUSTAT_MCDS))
 113                 return set_validity_icpt(scb_s, 0x0001U);
 114         else if (cpuflags & (CPUSTAT_SLSV | CPUSTAT_SLSR))
 115                 return set_validity_icpt(scb_s, 0x0007U);
 116
 117         /* intervention requests will be set later */
 118         newflags = CPUSTAT_ZARCH;
 119         if (cpuflags & CPUSTAT_GED && test_kvm_facility(vcpu->kvm, 8))
 120                 newflags |= CPUSTAT_GED;
 121         if (cpuflags & CPUSTAT_GED2 && test_kvm_facility(vcpu->kvm, 78)) {
 122                 if (cpuflags & CPUSTAT_GED)
 123                         return set_validity_icpt(scb_s, 0x0001U);
 124                 newflags |= CPUSTAT_GED2;
 125         }
 126         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GPERE))
 127                 newflags |= cpuflags & CPUSTAT_P;
 128         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_GSLS))
 129                 newflags |= cpuflags & CPUSTAT_SM;
 130         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS))
 131                 newflags |= cpuflags & CPUSTAT_IBS;
 132         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_KSS))
 133                 newflags |= cpuflags & CPUSTAT_KSS;
 134
 135         atomic_set(&scb_s->cpuflags, newflags);
 136         return 0;
 137 }
 138
 139 /*
 140  * Create a shadow copy of the crycb block and setup key wrapping, if
 141  * requested for guest 3 and enabled for guest 2.
 142  *
 143  * We only accept format-1 (no AP in g2), but convert it into format-2
 144  * There is nothing to do for format-0.
 145  *
 146  * Returns: - 0 if shadowed or nothing to do
 147  *          - > 0 if control has to be given to guest 2
 148  */
 149 static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 150 {
 151         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 152         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 153         const uint32_t crycbd_o = READ_ONCE(scb_o->crycbd);
 154         const u32 crycb_addr = crycbd_o & 0x7ffffff8U;
 155         unsigned long *b1, *b2;
 156         u8 ecb3_flags;
 157
 158         scb_s->crycbd = 0;
 159         if (!(crycbd_o & vcpu->arch.sie_block->crycbd & CRYCB_FORMAT1))
 160                 return 0;
 161         /* format-1 is supported with message-security-assist extension 3 */
 162         if (!test_kvm_facility(vcpu->kvm, 76))
 163                 return 0;
 164         /* we may only allow it if enabled for guest 2 */
 165         ecb3_flags = scb_o->ecb3 & vcpu->arch.sie_block->ecb3 &
 166                      (ECB3_AES | ECB3_DEA);
 167         if (!ecb3_flags)
 168                 return 0;
 169
 170         if ((crycb_addr & PAGE_MASK) != ((crycb_addr + 128) & PAGE_MASK))
 171                 return set_validity_icpt(scb_s, 0x003CU);
 172         else if (!crycb_addr)
 173                 return set_validity_icpt(scb_s, 0x0039U);
 174
 175         /* copy only the wrapping keys */
 176         if (read_guest_real(vcpu, crycb_addr + 72, &vsie_page->crycb, 56))
 177                 return set_validity_icpt(scb_s, 0x0035U);
 178
 179         scb_s->ecb3 |= ecb3_flags;
 180         scb_s->crycbd = ((__u32)(__u64) &vsie_page->crycb) | CRYCB_FORMAT1 |
 181                         CRYCB_FORMAT2;
 182
 183         /* xor both blocks in one run */
 184         b1 = (unsigned long *) vsie_page->crycb.dea_wrapping_key_mask;
 185         b2 = (unsigned long *)
 186                             vcpu->kvm->arch.crypto.crycb->dea_wrapping_key_mask;
 187         /* as 56%8 == 0, bitmap_xor won't overwrite any data */
 188         bitmap_xor(b1, b1, b2, BITS_PER_BYTE * 56);
 189         return 0;
 190 }
 191
 192 /* shadow (round up/down) the ibc to avoid validity icpt */
 193 static void prepare_ibc(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 194 {
 195         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 196         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 197         /* READ_ONCE does not work on bitfields - use a temporary variable */
 198         const uint32_t __new_ibc = scb_o->ibc;
 199         const uint32_t new_ibc = READ_ONCE(__new_ibc) & 0x0fffU;
 200         __u64 min_ibc = (sclp.ibc >> 16) & 0x0fffU;
 201
 202         scb_s->ibc = 0;
 203         /* ibc installed in g2 and requested for g3 */
 204         if (vcpu->kvm->arch.model.ibc && new_ibc) {
 205                 scb_s->ibc = new_ibc;
 206                 /* takte care of the minimum ibc level of the machine */
 207                 if (scb_s->ibc < min_ibc)
 208                         scb_s->ibc = min_ibc;
 209                 /* take care of the maximum ibc level set for the guest */
 210                 if (scb_s->ibc > vcpu->kvm->arch.model.ibc)
 211                         scb_s->ibc = vcpu->kvm->arch.model.ibc;
 212         }
 213 }
 214
 215 /* unshadow the scb, copying parameters back to the real scb */
 216 static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 217 {
 218         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 219         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 220
 221         /* interception */
 222         scb_o->icptcode = scb_s->icptcode;
 223         scb_o->icptstatus = scb_s->icptstatus;
 224         scb_o->ipa = scb_s->ipa;
 225         scb_o->ipb = scb_s->ipb;
 226         scb_o->gbea = scb_s->gbea;
 227
 228         /* timer */
 229         scb_o->cputm = scb_s->cputm;
 230         scb_o->ckc = scb_s->ckc;
 231         scb_o->todpr = scb_s->todpr;
 232
 233         /* guest state */
 234         scb_o->gpsw = scb_s->gpsw;
 235         scb_o->gg14 = scb_s->gg14;
 236         scb_o->gg15 = scb_s->gg15;
 237         memcpy(scb_o->gcr, scb_s->gcr, 128);
 238         scb_o->pp = scb_s->pp;
 239
 240         /* branch prediction */
 241         if (test_kvm_facility(vcpu->kvm, 82)) {
 242                 scb_o->fpf &= ~FPF_BPBC;
 243                 scb_o->fpf |= scb_s->fpf & FPF_BPBC;
 244         }
 245
 246         /* interrupt intercept */
 247         switch (scb_s->icptcode) {
 248         case ICPT_PROGI:
 249         case ICPT_INSTPROGI:
 250         case ICPT_EXTINT:
 251                 memcpy((void *)((u64)scb_o + 0xc0),
 252                        (void *)((u64)scb_s + 0xc0), 0xf0 - 0xc0);
 253                 break;
 254         case ICPT_PARTEXEC:
 255                 /* MVPG only */
 256                 memcpy((void *)((u64)scb_o + 0xc0),
 257                        (void *)((u64)scb_s + 0xc0), 0xd0 - 0xc0);
 258                 break;
 259         }
 260
 261         if (scb_s->ihcpu != 0xffffU)
 262                 scb_o->ihcpu = scb_s->ihcpu;
 263 }
 264
 265 /*
 266  * Setup the shadow scb by copying and checking the relevant parts of the g2
 267  * provided scb.
 268  *
 269  * Returns: - 0 if the scb has been shadowed
 270  *          - > 0 if control has to be given to guest 2
 271  */
 272 static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 273 {
 274         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 275         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 276         /* READ_ONCE does not work on bitfields - use a temporary variable */
 277         const uint32_t __new_prefix = scb_o->prefix;
 278         const uint32_t new_prefix = READ_ONCE(__new_prefix);
 279         const bool wants_tx = READ_ONCE(scb_o->ecb) & ECB_TE;
 280         bool had_tx = scb_s->ecb & ECB_TE;
 281         unsigned long new_mso = 0;
 282         int rc;
 283
 284         /* make sure we don't have any leftovers when reusing the scb */
 285         scb_s->icptcode = 0;
 286         scb_s->eca = 0;
 287         scb_s->ecb = 0;
 288         scb_s->ecb2 = 0;
 289         scb_s->ecb3 = 0;
 290         scb_s->ecd = 0;
 291         scb_s->fac = 0;
 292         scb_s->fpf = 0;
 293
 294         rc = prepare_cpuflags(vcpu, vsie_page);
 295         if (rc)
 296                 goto out;
 297
 298         /* timer */
 299         scb_s->cputm = scb_o->cputm;
 300         scb_s->ckc = scb_o->ckc;
 301         scb_s->todpr = scb_o->todpr;
 302         scb_s->epoch = scb_o->epoch;
 303
 304         /* guest state */
 305         scb_s->gpsw = scb_o->gpsw;
 306         scb_s->gg14 = scb_o->gg14;
 307         scb_s->gg15 = scb_o->gg15;
 308         memcpy(scb_s->gcr, scb_o->gcr, 128);
 309         scb_s->pp = scb_o->pp;
 310
 311         /* interception / execution handling */
 312         scb_s->gbea = scb_o->gbea;
 313         scb_s->lctl = scb_o->lctl;
 314         scb_s->svcc = scb_o->svcc;
 315         scb_s->ictl = scb_o->ictl;
 316         /*
 317          * SKEY handling functions can't deal with false setting of PTE invalid
 318          * bits. Therefore we cannot provide interpretation and would later
 319          * have to provide own emulation handlers.
 320          */
 321         if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_KSS))
 322                 scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
 323
 324         scb_s->icpua = scb_o->icpua;
 325
 326         if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM))
 327                 new_mso = READ_ONCE(scb_o->mso) & 0xfffffffffff00000UL;
 328         /* if the hva of the prefix changes, we have to remap the prefix */
 329         if (scb_s->mso != new_mso || scb_s->prefix != new_prefix)
 330                 prefix_unmapped(vsie_page);
 331          /* SIE will do mso/msl validity and exception checks for us */
 332         scb_s->msl = scb_o->msl & 0xfffffffffff00000UL;
 333         scb_s->mso = new_mso;
 334         scb_s->prefix = new_prefix;
 335
 336         /* We have to definetly flush the tlb if this scb never ran */
 337         if (scb_s->ihcpu != 0xffffU)
 338                 scb_s->ihcpu = scb_o->ihcpu;
 339
 340         /* MVPG and Protection Exception Interpretation are always available */
 341         scb_s->eca |= scb_o->eca & (ECA_MVPGI | ECA_PROTEXCI);
 342         /* Host-protection-interruption introduced with ESOP */
 343         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_ESOP))
 344                 scb_s->ecb |= scb_o->ecb & ECB_HOSTPROTINT;
 345         /* transactional execution */
 346         if (test_kvm_facility(vcpu->kvm, 73) && wants_tx) {
 347                 /* remap the prefix is tx is toggled on */
 348                 if (!had_tx)
 349                         prefix_unmapped(vsie_page);
 350                 scb_s->ecb |= ECB_TE;
 351         }
 352         /* branch prediction */
 353         if (test_kvm_facility(vcpu->kvm, 82))
 354                 scb_s->fpf |= scb_o->fpf & FPF_BPBC;
 355         /* SIMD */
 356         if (test_kvm_facility(vcpu->kvm, 129)) {
 357                 scb_s->eca |= scb_o->eca & ECA_VX;
 358                 scb_s->ecd |= scb_o->ecd & ECD_HOSTREGMGMT;
 359         }
 360         /* Run-time-Instrumentation */
 361         if (test_kvm_facility(vcpu->kvm, 64))
 362                 scb_s->ecb3 |= scb_o->ecb3 & ECB3_RI;
 363         /* Instruction Execution Prevention */
 364         if (test_kvm_facility(vcpu->kvm, 130))
 365                 scb_s->ecb2 |= scb_o->ecb2 & ECB2_IEP;
 366         /* Guarded Storage */
 367         if (test_kvm_facility(vcpu->kvm, 133)) {
 368                 scb_s->ecb |= scb_o->ecb & ECB_GS;
 369                 scb_s->ecd |= scb_o->ecd & ECD_HOSTREGMGMT;
 370         }
 371         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIIF))
 372                 scb_s->eca |= scb_o->eca & ECA_SII;
 373         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IB))
 374                 scb_s->eca |= scb_o->eca & ECA_IB;
 375         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI))
 376                 scb_s->eca |= scb_o->eca & ECA_CEI;
 377         /* Epoch Extension */
 378         if (test_kvm_facility(vcpu->kvm, 139))
 379                 scb_s->ecd |= scb_o->ecd & ECD_MEF;
 380
 381         prepare_ibc(vcpu, vsie_page);
 382         rc = shadow_crycb(vcpu, vsie_page);
 383 out:
 384         if (rc)
 385                 unshadow_scb(vcpu, vsie_page);
 386         return rc;
 387 }
 388
 389 void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start,
 390                                  unsigned long end)
 391 {
 392         struct kvm *kvm = gmap->private;
 393         struct vsie_page *cur;
 394         unsigned long prefix;
 395         struct page *page;
 396         int i;
 397
 398         if (!gmap_is_shadow(gmap))
 399                 return;
 400         if (start >= 1UL << 31)
 401                 /* We are only interested in prefix pages */
 402                 return;
 403
 404         /*
 405          * Only new shadow blocks are added to the list during runtime,
 406          * therefore we can safely reference them all the time.
 407          */
 408         for (i = 0; i < kvm->arch.vsie.page_count; i++) {
 409                 page = READ_ONCE(kvm->arch.vsie.pages[i]);
 410                 if (!page)
 411                         continue;
 412                 cur = page_to_virt(page);
 413                 if (READ_ONCE(cur->gmap) != gmap)
 414                         continue;
 415                 prefix = cur->scb_s.prefix << GUEST_PREFIX_SHIFT;
 416                 /* with mso/msl, the prefix lies at an offset */
 417                 prefix += cur->scb_s.mso;
 418                 if (prefix <= end && start <= prefix + 2 * PAGE_SIZE - 1)
 419                         prefix_unmapped_sync(cur);
 420         }
 421 }
 422
 423 /*
 424  * Map the first prefix page and if tx is enabled also the second prefix page.
 425  *
 426  * The prefix will be protected, a gmap notifier will inform about unmaps.
 427  * The shadow scb must not be executed until the prefix is remapped, this is
 428  * guaranteed by properly handling PROG_REQUEST.
 429  *
 430  * Returns: - 0 on if successfully mapped or already mapped
 431  *          - > 0 if control has to be given to guest 2
 432  *          - -EAGAIN if the caller can retry immediately
 433  *          - -ENOMEM if out of memory
 434  */
 435 static int map_prefix(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 436 {
 437         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 438         u64 prefix = scb_s->prefix << GUEST_PREFIX_SHIFT;
 439         int rc;
 440
 441         if (prefix_is_mapped(vsie_page))
 442                 return 0;
 443
 444         /* mark it as mapped so we can catch any concurrent unmappers */
 445         prefix_mapped(vsie_page);
 446
 447         /* with mso/msl, the prefix lies at offset *mso* */
 448         prefix += scb_s->mso;
 449
 450         rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, prefix);
 451         if (!rc && (scb_s->ecb & ECB_TE))
 452                 rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
 453                                            prefix + PAGE_SIZE);
 454         /*
 455          * We don't have to mprotect, we will be called for all unshadows.
 456          * SIE will detect if protection applies and trigger a validity.
 457          */
 458         if (rc)
 459                 prefix_unmapped(vsie_page);
 460         if (rc > 0 || rc == -EFAULT)
 461                 rc = set_validity_icpt(scb_s, 0x0037U);
 462         return rc;
 463 }
 464
 465 /*
 466  * Pin the guest page given by gpa and set hpa to the pinned host address.
 467  * Will always be pinned writable.
 468  *
 469  * Returns: - 0 on success
 470  *          - -EINVAL if the gpa is not valid guest storage
 471  */
 472 static int pin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t *hpa)
 473 {
 474         struct page *page;
 475
 476         page = gfn_to_page(kvm, gpa_to_gfn(gpa));
 477         if (is_error_page(page))
 478                 return -EINVAL;
 479         *hpa = (hpa_t) page_to_virt(page) + (gpa & ~PAGE_MASK);
 480         return 0;
 481 }
 482
 483 /* Unpins a page previously pinned via pin_guest_page, marking it as dirty. */
 484 static void unpin_guest_page(struct kvm *kvm, gpa_t gpa, hpa_t hpa)
 485 {
 486         kvm_release_pfn_dirty(hpa >> PAGE_SHIFT);
 487         /* mark the page always as dirty for migration */
 488         mark_page_dirty(kvm, gpa_to_gfn(gpa));
 489 }
 490
 491 /* unpin all blocks previously pinned by pin_blocks(), marking them dirty */
 492 static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 493 {
 494         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 495         hpa_t hpa;
 496
 497         hpa = (u64) scb_s->scaoh << 32 | scb_s->scaol;
 498         if (hpa) {
 499                 unpin_guest_page(vcpu->kvm, vsie_page->sca_gpa, hpa);
 500                 vsie_page->sca_gpa = 0;
 501                 scb_s->scaol = 0;
 502                 scb_s->scaoh = 0;
 503         }
 504
 505         hpa = scb_s->itdba;
 506         if (hpa) {
 507                 unpin_guest_page(vcpu->kvm, vsie_page->itdba_gpa, hpa);
 508                 vsie_page->itdba_gpa = 0;
 509                 scb_s->itdba = 0;
 510         }
 511
 512         hpa = scb_s->gvrd;
 513         if (hpa) {
 514                 unpin_guest_page(vcpu->kvm, vsie_page->gvrd_gpa, hpa);
 515                 vsie_page->gvrd_gpa = 0;
 516                 scb_s->gvrd = 0;
 517         }
 518
 519         hpa = scb_s->riccbd;
 520         if (hpa) {
 521                 unpin_guest_page(vcpu->kvm, vsie_page->riccbd_gpa, hpa);
 522                 vsie_page->riccbd_gpa = 0;
 523                 scb_s->riccbd = 0;
 524         }
 525
 526         hpa = scb_s->sdnxo;
 527         if (hpa) {
 528                 unpin_guest_page(vcpu->kvm, vsie_page->sdnx_gpa, hpa);
 529                 vsie_page->sdnx_gpa = 0;
 530                 scb_s->sdnxo = 0;
 531         }
 532 }
 533
 534 /*
 535  * Instead of shadowing some blocks, we can simply forward them because the
 536  * addresses in the scb are 64 bit long.
 537  *
 538  * This works as long as the data lies in one page. If blocks ever exceed one
 539  * page, we have to fall back to shadowing.
 540  *
 541  * As we reuse the sca, the vcpu pointers contained in it are invalid. We must
 542  * therefore not enable any facilities that access these pointers (e.g. SIGPIF).
 543  *
 544  * Returns: - 0 if all blocks were pinned.
 545  *          - > 0 if control has to be given to guest 2
 546  *          - -ENOMEM if out of memory
 547  */
 548 static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 549 {
 550         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 551         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 552         hpa_t hpa;
 553         gpa_t gpa;
 554         int rc = 0;
 555
 556         gpa = READ_ONCE(scb_o->scaol) & ~0xfUL;
 557         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_64BSCAO))
 558                 gpa |= (u64) READ_ONCE(scb_o->scaoh) << 32;
 559         if (gpa) {
 560                 if (!(gpa & ~0x1fffUL))
 561                         rc = set_validity_icpt(scb_s, 0x0038U);
 562                 else if ((gpa & ~0x1fffUL) == kvm_s390_get_prefix(vcpu))
 563                         rc = set_validity_icpt(scb_s, 0x0011U);
 564                 else if ((gpa & PAGE_MASK) !=
 565                          ((gpa + sizeof(struct bsca_block) - 1) & PAGE_MASK))
 566                         rc = set_validity_icpt(scb_s, 0x003bU);
 567                 if (!rc) {
 568                         rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
 569                         if (rc)
 570                                 rc = set_validity_icpt(scb_s, 0x0034U);
 571                 }
 572                 if (rc)
 573                         goto unpin;
 574                 vsie_page->sca_gpa = gpa;
 575                 scb_s->scaoh = (u32)((u64)hpa >> 32);
 576                 scb_s->scaol = (u32)(u64)hpa;
 577         }
 578
 579         gpa = READ_ONCE(scb_o->itdba) & ~0xffUL;
 580         if (gpa && (scb_s->ecb & ECB_TE)) {
 581                 if (!(gpa & ~0x1fffU)) {
 582                         rc = set_validity_icpt(scb_s, 0x0080U);
 583                         goto unpin;
 584                 }
 585                 /* 256 bytes cannot cross page boundaries */
 586                 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
 587                 if (rc) {
 588                         rc = set_validity_icpt(scb_s, 0x0080U);
 589                         goto unpin;
 590                 }
 591                 vsie_page->itdba_gpa = gpa;
 592                 scb_s->itdba = hpa;
 593         }
 594
 595         gpa = READ_ONCE(scb_o->gvrd) & ~0x1ffUL;
 596         if (gpa && (scb_s->eca & ECA_VX) && !(scb_s->ecd & ECD_HOSTREGMGMT)) {
 597                 if (!(gpa & ~0x1fffUL)) {
 598                         rc = set_validity_icpt(scb_s, 0x1310U);
 599                         goto unpin;
 600                 }
 601                 /*
 602                  * 512 bytes vector registers cannot cross page boundaries
 603                  * if this block gets bigger, we have to shadow it.
 604                  */
 605                 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
 606                 if (rc) {
 607                         rc = set_validity_icpt(scb_s, 0x1310U);
 608                         goto unpin;
 609                 }
 610                 vsie_page->gvrd_gpa = gpa;
 611                 scb_s->gvrd = hpa;
 612         }
 613
 614         gpa = READ_ONCE(scb_o->riccbd) & ~0x3fUL;
 615         if (gpa && (scb_s->ecb3 & ECB3_RI)) {
 616                 if (!(gpa & ~0x1fffUL)) {
 617                         rc = set_validity_icpt(scb_s, 0x0043U);
 618                         goto unpin;
 619                 }
 620                 /* 64 bytes cannot cross page boundaries */
 621                 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
 622                 if (rc) {
 623                         rc = set_validity_icpt(scb_s, 0x0043U);
 624                         goto unpin;
 625                 }
 626                 /* Validity 0x0044 will be checked by SIE */
 627                 vsie_page->riccbd_gpa = gpa;
 628                 scb_s->riccbd = hpa;
 629         }
 630         if ((scb_s->ecb & ECB_GS) && !(scb_s->ecd & ECD_HOSTREGMGMT)) {
 631                 unsigned long sdnxc;
 632
 633                 gpa = READ_ONCE(scb_o->sdnxo) & ~0xfUL;
 634                 sdnxc = READ_ONCE(scb_o->sdnxo) & 0xfUL;
 635                 if (!gpa || !(gpa & ~0x1fffUL)) {
 636                         rc = set_validity_icpt(scb_s, 0x10b0U);
 637                         goto unpin;
 638                 }
 639                 if (sdnxc < 6 || sdnxc > 12) {
 640                         rc = set_validity_icpt(scb_s, 0x10b1U);
 641                         goto unpin;
 642                 }
 643                 if (gpa & ((1 << sdnxc) - 1)) {
 644                         rc = set_validity_icpt(scb_s, 0x10b2U);
 645                         goto unpin;
 646                 }
 647                 /* Due to alignment rules (checked above) this cannot
 648                  * cross page boundaries
 649                  */
 650                 rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
 651                 if (rc) {
 652                         rc = set_validity_icpt(scb_s, 0x10b0U);
 653                         goto unpin;
 654                 }
 655                 vsie_page->sdnx_gpa = gpa;
 656                 scb_s->sdnxo = hpa | sdnxc;
 657         }
 658         return 0;
 659 unpin:
 660         unpin_blocks(vcpu, vsie_page);
 661         return rc;
 662 }
 663
 664 /* unpin the scb provided by guest 2, marking it as dirty */
 665 static void unpin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page,
 666                       gpa_t gpa)
 667 {
 668         hpa_t hpa = (hpa_t) vsie_page->scb_o;
 669
 670         if (hpa)
 671                 unpin_guest_page(vcpu->kvm, gpa, hpa);
 672         vsie_page->scb_o = NULL;
 673 }
 674
 675 /*
 676  * Pin the scb at gpa provided by guest 2 at vsie_page->scb_o.
 677  *
 678  * Returns: - 0 if the scb was pinned.
 679  *          - > 0 if control has to be given to guest 2
 680  */
 681 static int pin_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page,
 682                    gpa_t gpa)
 683 {
 684         hpa_t hpa;
 685         int rc;
 686
 687         rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
 688         if (rc) {
 689                 rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
 690                 WARN_ON_ONCE(rc);
 691                 return 1;
 692         }
 693         vsie_page->scb_o = (struct kvm_s390_sie_block *) hpa;
 694         return 0;
 695 }
 696
 697 /*
 698  * Inject a fault into guest 2.
 699  *
 700  * Returns: - > 0 if control has to be given to guest 2
 701  *            < 0 if an error occurred during injection.
 702  */
 703 static int inject_fault(struct kvm_vcpu *vcpu, __u16 code, __u64 vaddr,
 704                         bool write_flag)
 705 {
 706         struct kvm_s390_pgm_info pgm = {
 707                 .code = code,
 708                 .trans_exc_code =
 709                         /* 0-51: virtual address */
 710                         (vaddr & 0xfffffffffffff000UL) |
 711                         /* 52-53: store / fetch */
 712                         (((unsigned int) !write_flag) + 1) << 10,
 713                         /* 62-63: asce id (alway primary == 0) */
 714                 .exc_access_id = 0, /* always primary */
 715                 .op_access_id = 0, /* not MVPG */
 716         };
 717         int rc;
 718
 719         if (code == PGM_PROTECTION)
 720                 pgm.trans_exc_code |= 0x4UL;
 721
 722         rc = kvm_s390_inject_prog_irq(vcpu, &pgm);
 723         return rc ? rc : 1;
 724 }
 725
 726 /*
 727  * Handle a fault during vsie execution on a gmap shadow.
 728  *
 729  * Returns: - 0 if the fault was resolved
 730  *          - > 0 if control has to be given to guest 2
 731  *          - < 0 if an error occurred
 732  */
 733 static int handle_fault(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 734 {
 735         int rc;
 736
 737         if (current->thread.gmap_int_code == PGM_PROTECTION)
 738                 /* we can directly forward all protection exceptions */
 739                 return inject_fault(vcpu, PGM_PROTECTION,
 740                                     current->thread.gmap_addr, 1);
 741
 742         rc = kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
 743                                    current->thread.gmap_addr);
 744         if (rc > 0) {
 745                 rc = inject_fault(vcpu, rc,
 746                                   current->thread.gmap_addr,
 747                                   current->thread.gmap_write_flag);
 748                 if (rc >= 0)
 749                         vsie_page->fault_addr = current->thread.gmap_addr;
 750         }
 751         return rc;
 752 }
 753
 754 /*
 755  * Retry the previous fault that required guest 2 intervention. This avoids
 756  * one superfluous SIE re-entry and direct exit.
 757  *
 758  * Will ignore any errors. The next SIE fault will do proper fault handling.
 759  */
 760 static void handle_last_fault(struct kvm_vcpu *vcpu,
 761                               struct vsie_page *vsie_page)
 762 {
 763         if (vsie_page->fault_addr)
 764                 kvm_s390_shadow_fault(vcpu, vsie_page->gmap,
 765                                       vsie_page->fault_addr);
 766         vsie_page->fault_addr = 0;
 767 }
 768
 769 static inline void clear_vsie_icpt(struct vsie_page *vsie_page)
 770 {
 771         vsie_page->scb_s.icptcode = 0;
 772 }
 773
 774 /* rewind the psw and clear the vsie icpt, so we can retry execution */
 775 static void retry_vsie_icpt(struct vsie_page *vsie_page)
 776 {
 777         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 778         int ilen = insn_length(scb_s->ipa >> 8);
 779
 780         /* take care of EXECUTE instructions */
 781         if (scb_s->icptstatus & 1) {
 782                 ilen = (scb_s->icptstatus >> 4) & 0x6;
 783                 if (!ilen)
 784                         ilen = 4;
 785         }
 786         scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, ilen);
 787         clear_vsie_icpt(vsie_page);
 788 }
 789
 790 /*
 791  * Try to shadow + enable the guest 2 provided facility list.
 792  * Retry instruction execution if enabled for and provided by guest 2.
 793  *
 794  * Returns: - 0 if handled (retry or guest 2 icpt)
 795  *          - > 0 if control has to be given to guest 2
 796  */
 797 static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 798 {
 799         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 800         __u32 fac = READ_ONCE(vsie_page->scb_o->fac) & 0x7ffffff8U;
 801
 802         if (fac && test_kvm_facility(vcpu->kvm, 7)) {
 803                 retry_vsie_icpt(vsie_page);
 804                 if (read_guest_real(vcpu, fac, &vsie_page->fac,
 805                                     sizeof(vsie_page->fac)))
 806                         return set_validity_icpt(scb_s, 0x1090U);
 807                 scb_s->fac = (__u32)(__u64) &vsie_page->fac;
 808         }
 809         return 0;
 810 }
 811
 812 /*
 813  * Run the vsie on a shadow scb and a shadow gmap, without any further
 814  * sanity checks, handling SIE faults.
 815  *
 816  * Returns: - 0 everything went fine
 817  *          - > 0 if control has to be given to guest 2
 818  *          - < 0 if an error occurred
 819  */
 820 static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 821 {
 822         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 823         struct kvm_s390_sie_block *scb_o = vsie_page->scb_o;
 824         int rc;
 825
 826         handle_last_fault(vcpu, vsie_page);
 827
 828         if (need_resched())
 829                 schedule();
 830         if (test_cpu_flag(CIF_MCCK_PENDING))
 831                 s390_handle_mcck();
 832
 833         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 834         local_irq_disable();
 835         guest_enter_irqoff();
 836         local_irq_enable();
 837
 838         rc = sie64a(scb_s, vcpu->run->s.regs.gprs);
 839
 840         local_irq_disable();
 841         guest_exit_irqoff();
 842         local_irq_enable();
 843         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 844
 845         if (rc == -EINTR) {
 846                 VCPU_EVENT(vcpu, 3, "%s", "machine check");
 847                 kvm_s390_reinject_machine_check(vcpu, &vsie_page->mcck_info);
 848                 return 0;
 849         }
 850
 851         if (rc > 0)
 852                 rc = 0; /* we could still have an icpt */
 853         else if (rc == -EFAULT)
 854                 return handle_fault(vcpu, vsie_page);
 855
 856         switch (scb_s->icptcode) {
 857         case ICPT_INST:
 858                 if (scb_s->ipa == 0xb2b0)
 859                         rc = handle_stfle(vcpu, vsie_page);
 860                 break;
 861         case ICPT_STOP:
 862                 /* stop not requested by g2 - must have been a kick */
 863                 if (!(atomic_read(&scb_o->cpuflags) & CPUSTAT_STOP_INT))
 864                         clear_vsie_icpt(vsie_page);
 865                 break;
 866         case ICPT_VALIDITY:
 867                 if ((scb_s->ipa & 0xf000) != 0xf000)
 868                         scb_s->ipa += 0x1000;
 869                 break;
 870         }
 871         return rc;
 872 }
 873
 874 static void release_gmap_shadow(struct vsie_page *vsie_page)
 875 {
 876         if (vsie_page->gmap)
 877                 gmap_put(vsie_page->gmap);
 878         WRITE_ONCE(vsie_page->gmap, NULL);
 879         prefix_unmapped(vsie_page);
 880 }
 881
 882 static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
 883                                struct vsie_page *vsie_page)
 884 {
 885         unsigned long asce;
 886         union ctlreg0 cr0;
 887         struct gmap *gmap;
 888         int edat;
 889
 890         asce = vcpu->arch.sie_block->gcr[1];
 891         cr0.val = vcpu->arch.sie_block->gcr[0];
 892         edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
 893         edat += edat && test_kvm_facility(vcpu->kvm, 78);
 894
 895         /*
 896          * ASCE or EDAT could have changed since last icpt, or the gmap
 897          * we're holding has been unshadowed. If the gmap is still valid,
 898          * we can safely reuse it.
 899          */
 900         if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat))
 901                 return 0;
 902
 903         /* release the old shadow - if any, and mark the prefix as unmapped */
 904         release_gmap_shadow(vsie_page);
 905         gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
 906         if (IS_ERR(gmap))
 907                 return PTR_ERR(gmap);
 908         gmap->private = vcpu->kvm;
 909         WRITE_ONCE(vsie_page->gmap, gmap);
 910         return 0;
 911 }
 912
 913 /*
 914  * Register the shadow scb at the VCPU, e.g. for kicking out of vsie.
 915  */
 916 static void register_shadow_scb(struct kvm_vcpu *vcpu,
 917                                 struct vsie_page *vsie_page)
 918 {
 919         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 920
 921         WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s);
 922         /*
 923          * External calls have to lead to a kick of the vcpu and
 924          * therefore the vsie -> Simulate Wait state.
 925          */
 926         kvm_s390_set_cpuflags(vcpu, CPUSTAT_WAIT);
 927         /*
 928          * We have to adjust the g3 epoch by the g2 epoch. The epoch will
 929          * automatically be adjusted on tod clock changes via kvm_sync_clock.
 930          */
 931         preempt_disable();
 932         scb_s->epoch += vcpu->kvm->arch.epoch;
 933
 934         if (scb_s->ecd & ECD_MEF) {
 935                 scb_s->epdx += vcpu->kvm->arch.epdx;
 936                 if (scb_s->epoch < vcpu->kvm->arch.epoch)
 937                         scb_s->epdx += 1;
 938         }
 939
 940         preempt_enable();
 941 }
 942
 943 /*
 944  * Unregister a shadow scb from a VCPU.
 945  */
 946 static void unregister_shadow_scb(struct kvm_vcpu *vcpu)
 947 {
 948         kvm_s390_clear_cpuflags(vcpu, CPUSTAT_WAIT);
 949         WRITE_ONCE(vcpu->arch.vsie_block, NULL);
 950 }
 951
 952 /*
 953  * Run the vsie on a shadowed scb, managing the gmap shadow, handling
 954  * prefix pages and faults.
 955  *
 956  * Returns: - 0 if no errors occurred
 957  *          - > 0 if control has to be given to guest 2
 958  *          - -ENOMEM if out of memory
 959  */
 960 static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 961 {
 962         struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
 963         int rc = 0;
 964
 965         while (1) {
 966                 rc = acquire_gmap_shadow(vcpu, vsie_page);
 967                 if (!rc)
 968                         rc = map_prefix(vcpu, vsie_page);
 969                 if (!rc) {
 970                         gmap_enable(vsie_page->gmap);
 971                         update_intervention_requests(vsie_page);
 972                         rc = do_vsie_run(vcpu, vsie_page);
 973                         gmap_enable(vcpu->arch.gmap);
 974                 }
 975                 atomic_andnot(PROG_BLOCK_SIE, &scb_s->prog20);
 976
 977                 if (rc == -EAGAIN)
 978                         rc = 0;
 979                 if (rc || scb_s->icptcode || signal_pending(current) ||
 980                     kvm_s390_vcpu_has_irq(vcpu, 0))
 981                         break;
 982         }
 983
 984         if (rc == -EFAULT) {
 985                 /*
 986                  * Addressing exceptions are always presentes as intercepts.
 987                  * As addressing exceptions are suppressing and our guest 3 PSW
 988                  * points at the responsible instruction, we have to
 989                  * forward the PSW and set the ilc. If we can't read guest 3
 990                  * instruction, we can use an arbitrary ilc. Let's always use
 991                  * ilen = 4 for now, so we can avoid reading in guest 3 virtual
 992                  * memory. (we could also fake the shadow so the hardware
 993                  * handles it).
 994                  */
 995                 scb_s->icptcode = ICPT_PROGI;
 996                 scb_s->iprcc = PGM_ADDRESSING;
 997                 scb_s->pgmilc = 4;
 998                 scb_s->gpsw.addr = __rewind_psw(scb_s->gpsw, 4);
 999         }
1000         return rc;
1001 }
1002
1003 /*
1004  * Get or create a vsie page for a scb address.
1005  *
1006  * Returns: - address of a vsie page (cached or new one)
1007  *          - NULL if the same scb address is already used by another VCPU
1008  *          - ERR_PTR(-ENOMEM) if out of memory
1009  */
1010 static struct vsie_page *get_vsie_page(struct kvm *kvm, unsigned long addr)
1011 {
1012         struct vsie_page *vsie_page;
1013         struct page *page;
1014         int nr_vcpus;
1015
1016         rcu_read_lock();
1017         page = radix_tree_lookup(&kvm->arch.vsie.addr_to_page, addr >> 9);
1018         rcu_read_unlock();
1019         if (page) {
1020                 if (page_ref_inc_return(page) == 2)
1021                         return page_to_virt(page);
1022                 page_ref_dec(page);
1023         }
1024
1025         /*
1026          * We want at least #online_vcpus shadows, so every VCPU can execute
1027          * the VSIE in parallel.
1028          */
1029         nr_vcpus = atomic_read(&kvm->online_vcpus);
1030
1031         mutex_lock(&kvm->arch.vsie.mutex);
1032         if (kvm->arch.vsie.page_count < nr_vcpus) {
1033                 page = alloc_page(GFP_KERNEL | __GFP_ZERO | GFP_DMA);
1034                 if (!page) {
1035                         mutex_unlock(&kvm->arch.vsie.mutex);
1036                         return ERR_PTR(-ENOMEM);
1037                 }
1038                 page_ref_inc(page);
1039                 kvm->arch.vsie.pages[kvm->arch.vsie.page_count] = page;
1040                 kvm->arch.vsie.page_count++;
1041         } else {
1042                 /* reuse an existing entry that belongs to nobody */
1043                 while (true) {
1044                         page = kvm->arch.vsie.pages[kvm->arch.vsie.next];
1045                         if (page_ref_inc_return(page) == 2)
1046                                 break;
1047                         page_ref_dec(page);
1048                         kvm->arch.vsie.next++;
1049                         kvm->arch.vsie.next %= nr_vcpus;
1050                 }
1051                 radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
1052         }
1053         page->index = addr;
1054         /* double use of the same address */
1055         if (radix_tree_insert(&kvm->arch.vsie.addr_to_page, addr >> 9, page)) {
1056                 page_ref_dec(page);
1057                 mutex_unlock(&kvm->arch.vsie.mutex);
1058                 return NULL;
1059         }
1060         mutex_unlock(&kvm->arch.vsie.mutex);
1061
1062         vsie_page = page_to_virt(page);
1063         memset(&vsie_page->scb_s, 0, sizeof(struct kvm_s390_sie_block));
1064         release_gmap_shadow(vsie_page);
1065         vsie_page->fault_addr = 0;
1066         vsie_page->scb_s.ihcpu = 0xffffU;
1067         return vsie_page;
1068 }
1069
1070 /* put a vsie page acquired via get_vsie_page */
1071 static void put_vsie_page(struct kvm *kvm, struct vsie_page *vsie_page)
1072 {
1073         struct page *page = pfn_to_page(__pa(vsie_page) >> PAGE_SHIFT);
1074
1075         page_ref_dec(page);
1076 }
1077
1078 int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu)
1079 {
1080         struct vsie_page *vsie_page;
1081         unsigned long scb_addr;
1082         int rc;
1083
1084         vcpu->stat.instruction_sie++;
1085         if (!test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_SIEF2))
1086                 return -EOPNOTSUPP;
1087         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
1088                 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
1089
1090         BUILD_BUG_ON(sizeof(struct vsie_page) != PAGE_SIZE);
1091         scb_addr = kvm_s390_get_base_disp_s(vcpu, NULL);
1092
1093         /* 512 byte alignment */
1094         if (unlikely(scb_addr & 0x1ffUL))
1095                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
1096
1097         if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0))
1098                 return 0;
1099
1100         vsie_page = get_vsie_page(vcpu->kvm, scb_addr);
1101         if (IS_ERR(vsie_page))
1102                 return PTR_ERR(vsie_page);
1103         else if (!vsie_page)
1104                 /* double use of sie control block - simply do nothing */
1105                 return 0;
1106
1107         rc = pin_scb(vcpu, vsie_page, scb_addr);
1108         if (rc)
1109                 goto out_put;
1110         rc = shadow_scb(vcpu, vsie_page);
1111         if (rc)
1112                 goto out_unpin_scb;
1113         rc = pin_blocks(vcpu, vsie_page);
1114         if (rc)
1115                 goto out_unshadow;
1116         register_shadow_scb(vcpu, vsie_page);
1117         rc = vsie_run(vcpu, vsie_page);
1118         unregister_shadow_scb(vcpu);
1119         unpin_blocks(vcpu, vsie_page);
1120 out_unshadow:
1121         unshadow_scb(vcpu, vsie_page);
1122 out_unpin_scb:
1123         unpin_scb(vcpu, vsie_page, scb_addr);
1124 out_put:
1125         put_vsie_page(vcpu->kvm, vsie_page);
1126
1127         return rc < 0 ? rc : 0;
1128 }
1129
1130 /* Init the vsie data structures. To be called when a vm is initialized. */
1131 void kvm_s390_vsie_init(struct kvm *kvm)
1132 {
1133         mutex_init(&kvm->arch.vsie.mutex);
1134         INIT_RADIX_TREE(&kvm->arch.vsie.addr_to_page, GFP_KERNEL);
1135 }
1136
1137 /* Destroy the vsie data structures. To be called when a vm is destroyed. */
1138 void kvm_s390_vsie_destroy(struct kvm *kvm)
1139 {
1140         struct vsie_page *vsie_page;
1141         struct page *page;
1142         int i;
1143
1144         mutex_lock(&kvm->arch.vsie.mutex);
1145         for (i = 0; i < kvm->arch.vsie.page_count; i++) {
1146                 page = kvm->arch.vsie.pages[i];
1147                 kvm->arch.vsie.pages[i] = NULL;
1148                 vsie_page = page_to_virt(page);
1149                 release_gmap_shadow(vsie_page);
1150                 /* free the radix tree entry */
1151                 radix_tree_delete(&kvm->arch.vsie.addr_to_page, page->index >> 9);
1152                 __free_page(page);
1153         }
1154         kvm->arch.vsie.page_count = 0;
1155         mutex_unlock(&kvm->arch.vsie.mutex);
1156 }
1157
1158 void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu)
1159 {
1160         struct kvm_s390_sie_block *scb = READ_ONCE(vcpu->arch.vsie_block);
1161
1162         /*
1163          * Even if the VCPU lets go of the shadow sie block reference, it is
1164          * still valid in the cache. So we can safely kick it.
1165          */
1166         if (scb) {
1167                 atomic_or(PROG_BLOCK_SIE, &scb->prog20);
1168                 if (scb->prog0c & PROG_IN_SIE)
1169                         atomic_or(CPUSTAT_STOP_INT, &scb->cpuflags);
1170         }
1171 }