arch/s390/kvm/kvm-s390.c

   1 /*
   2  * hosting zSeries kernel virtual machines
   3  *
   4  * Copyright IBM Corp. 2008, 2009
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License (version 2 only)
   8  * as published by the Free Software Foundation.
   9  *
  10  *    Author(s): Carsten Otte <cotte@de.ibm.com>
  11  *               Christian Borntraeger <borntraeger@de.ibm.com>
  12  *               Heiko Carstens <heiko.carstens@de.ibm.com>
  13  *               Christian Ehrhardt <ehrhardt@de.ibm.com>
  14  */
  15
  16 #include <linux/compiler.h>
  17 #include <linux/err.h>
  18 #include <linux/fs.h>
  19 #include <linux/hrtimer.h>
  20 #include <linux/init.h>
  21 #include <linux/kvm.h>
  22 #include <linux/kvm_host.h>
  23 #include <linux/module.h>
  24 #include <linux/slab.h>
  25 #include <linux/timer.h>
  26 #include <asm/asm-offsets.h>
  27 #include <asm/lowcore.h>
  28 #include <asm/pgtable.h>
  29 #include <asm/nmi.h>
  30 #include <asm/switch_to.h>
  31 #include <asm/facility.h>
  32 #include <asm/sclp.h>
  33 #include "kvm-s390.h"
  34 #include "gaccess.h"
  35
  36 #define CREATE_TRACE_POINTS
  37 #include "trace.h"
  38 #include "trace-s390.h"
  39
  40 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
  41
  42 struct kvm_stats_debugfs_item debugfs_entries[] = {
  43         { "userspace_handled", VCPU_STAT(exit_userspace) },
  44         { "exit_null", VCPU_STAT(exit_null) },
  45         { "exit_validity", VCPU_STAT(exit_validity) },
  46         { "exit_stop_request", VCPU_STAT(exit_stop_request) },
  47         { "exit_external_request", VCPU_STAT(exit_external_request) },
  48         { "exit_external_interrupt", VCPU_STAT(exit_external_interrupt) },
  49         { "exit_instruction", VCPU_STAT(exit_instruction) },
  50         { "exit_program_interruption", VCPU_STAT(exit_program_interruption) },
  51         { "exit_instr_and_program_int", VCPU_STAT(exit_instr_and_program) },
  52         { "instruction_lctlg", VCPU_STAT(instruction_lctlg) },
  53         { "instruction_lctl", VCPU_STAT(instruction_lctl) },
  54         { "deliver_emergency_signal", VCPU_STAT(deliver_emergency_signal) },
  55         { "deliver_external_call", VCPU_STAT(deliver_external_call) },
  56         { "deliver_service_signal", VCPU_STAT(deliver_service_signal) },
  57         { "deliver_virtio_interrupt", VCPU_STAT(deliver_virtio_interrupt) },
  58         { "deliver_stop_signal", VCPU_STAT(deliver_stop_signal) },
  59         { "deliver_prefix_signal", VCPU_STAT(deliver_prefix_signal) },
  60         { "deliver_restart_signal", VCPU_STAT(deliver_restart_signal) },
  61         { "deliver_program_interruption", VCPU_STAT(deliver_program_int) },
  62         { "exit_wait_state", VCPU_STAT(exit_wait_state) },
  63         { "instruction_pfmf", VCPU_STAT(instruction_pfmf) },
  64         { "instruction_stidp", VCPU_STAT(instruction_stidp) },
  65         { "instruction_spx", VCPU_STAT(instruction_spx) },
  66         { "instruction_stpx", VCPU_STAT(instruction_stpx) },
  67         { "instruction_stap", VCPU_STAT(instruction_stap) },
  68         { "instruction_storage_key", VCPU_STAT(instruction_storage_key) },
  69         { "instruction_stsch", VCPU_STAT(instruction_stsch) },
  70         { "instruction_chsc", VCPU_STAT(instruction_chsc) },
  71         { "instruction_stsi", VCPU_STAT(instruction_stsi) },
  72         { "instruction_stfl", VCPU_STAT(instruction_stfl) },
  73         { "instruction_tprot", VCPU_STAT(instruction_tprot) },
  74         { "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) },
  75         { "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) },
  76         { "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) },
  77         { "instruction_sigp_emergency", VCPU_STAT(instruction_sigp_emergency) },
  78         { "instruction_sigp_stop", VCPU_STAT(instruction_sigp_stop) },
  79         { "instruction_sigp_set_arch", VCPU_STAT(instruction_sigp_arch) },
  80         { "instruction_sigp_set_prefix", VCPU_STAT(instruction_sigp_prefix) },
  81         { "instruction_sigp_restart", VCPU_STAT(instruction_sigp_restart) },
  82         { "diagnose_10", VCPU_STAT(diagnose_10) },
  83         { "diagnose_44", VCPU_STAT(diagnose_44) },
  84         { "diagnose_9c", VCPU_STAT(diagnose_9c) },
  85         { NULL }
  86 };
  87
  88 unsigned long *vfacilities;
  89 static struct gmap_notifier gmap_notifier;
  90
  91 /* test availability of vfacility */
  92 static inline int test_vfacility(unsigned long nr)
  93 {
  94         return __test_facility(nr, (void *) vfacilities);
  95 }
  96
  97 /* Section: not file related */
  98 int kvm_arch_hardware_enable(void *garbage)
  99 {
 100         /* every s390 is virtualization enabled ;-) */
 101         return 0;
 102 }
 103
 104 void kvm_arch_hardware_disable(void *garbage)
 105 {
 106 }
 107
 108 static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address);
 109
 110 int kvm_arch_hardware_setup(void)
 111 {
 112         gmap_notifier.notifier_call = kvm_gmap_notifier;
 113         gmap_register_ipte_notifier(&gmap_notifier);
 114         return 0;
 115 }
 116
 117 void kvm_arch_hardware_unsetup(void)
 118 {
 119         gmap_unregister_ipte_notifier(&gmap_notifier);
 120 }
 121
 122 void kvm_arch_check_processor_compat(void *rtn)
 123 {
 124 }
 125
 126 int kvm_arch_init(void *opaque)
 127 {
 128         return 0;
 129 }
 130
 131 void kvm_arch_exit(void)
 132 {
 133 }
 134
 135 /* Section: device related */
 136 long kvm_arch_dev_ioctl(struct file *filp,
 137                         unsigned int ioctl, unsigned long arg)
 138 {
 139         if (ioctl == KVM_S390_ENABLE_SIE)
 140                 return s390_enable_sie();
 141         return -EINVAL;
 142 }
 143
 144 int kvm_dev_ioctl_check_extension(long ext)
 145 {
 146         int r;
 147
 148         switch (ext) {
 149         case KVM_CAP_S390_PSW:
 150         case KVM_CAP_S390_GMAP:
 151         case KVM_CAP_SYNC_MMU:
 152 #ifdef CONFIG_KVM_S390_UCONTROL
 153         case KVM_CAP_S390_UCONTROL:
 154 #endif
 155         case KVM_CAP_SYNC_REGS:
 156         case KVM_CAP_ONE_REG:
 157         case KVM_CAP_ENABLE_CAP:
 158         case KVM_CAP_S390_CSS_SUPPORT:
 159         case KVM_CAP_IOEVENTFD:
 160                 r = 1;
 161                 break;
 162         case KVM_CAP_NR_VCPUS:
 163         case KVM_CAP_MAX_VCPUS:
 164                 r = KVM_MAX_VCPUS;
 165                 break;
 166         case KVM_CAP_NR_MEMSLOTS:
 167                 r = KVM_USER_MEM_SLOTS;
 168                 break;
 169         case KVM_CAP_S390_COW:
 170                 r = MACHINE_HAS_ESOP;
 171                 break;
 172         default:
 173                 r = 0;
 174         }
 175         return r;
 176 }
 177
 178 /* Section: vm related */
 179 /*
 180  * Get (and clear) the dirty memory log for a memory slot.
 181  */
 182 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
 183                                struct kvm_dirty_log *log)
 184 {
 185         return 0;
 186 }
 187
 188 long kvm_arch_vm_ioctl(struct file *filp,
 189                        unsigned int ioctl, unsigned long arg)
 190 {
 191         struct kvm *kvm = filp->private_data;
 192         void __user *argp = (void __user *)arg;
 193         int r;
 194
 195         switch (ioctl) {
 196         case KVM_S390_INTERRUPT: {
 197                 struct kvm_s390_interrupt s390int;
 198
 199                 r = -EFAULT;
 200                 if (copy_from_user(&s390int, argp, sizeof(s390int)))
 201                         break;
 202                 r = kvm_s390_inject_vm(kvm, &s390int);
 203                 break;
 204         }
 205         default:
 206                 r = -ENOTTY;
 207         }
 208
 209         return r;
 210 }
 211
 212 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 213 {
 214         int rc;
 215         char debug_name[16];
 216
 217         rc = -EINVAL;
 218 #ifdef CONFIG_KVM_S390_UCONTROL
 219         if (type & ~KVM_VM_S390_UCONTROL)
 220                 goto out_err;
 221         if ((type & KVM_VM_S390_UCONTROL) && (!capable(CAP_SYS_ADMIN)))
 222                 goto out_err;
 223 #else
 224         if (type)
 225                 goto out_err;
 226 #endif
 227
 228         rc = s390_enable_sie();
 229         if (rc)
 230                 goto out_err;
 231
 232         rc = -ENOMEM;
 233
 234         kvm->arch.sca = (struct sca_block *) get_zeroed_page(GFP_KERNEL);
 235         if (!kvm->arch.sca)
 236                 goto out_err;
 237
 238         sprintf(debug_name, "kvm-%u", current->pid);
 239
 240         kvm->arch.dbf = debug_register(debug_name, 8, 2, 8 * sizeof(long));
 241         if (!kvm->arch.dbf)
 242                 goto out_nodbf;
 243
 244         spin_lock_init(&kvm->arch.float_int.lock);
 245         INIT_LIST_HEAD(&kvm->arch.float_int.list);
 246
 247         debug_register_view(kvm->arch.dbf, &debug_sprintf_view);
 248         VM_EVENT(kvm, 3, "%s", "vm created");
 249
 250         if (type & KVM_VM_S390_UCONTROL) {
 251                 kvm->arch.gmap = NULL;
 252         } else {
 253                 kvm->arch.gmap = gmap_alloc(current->mm);
 254                 if (!kvm->arch.gmap)
 255                         goto out_nogmap;
 256                 kvm->arch.gmap->private = kvm;
 257         }
 258
 259         kvm->arch.css_support = 0;
 260
 261         return 0;
 262 out_nogmap:
 263         debug_unregister(kvm->arch.dbf);
 264 out_nodbf:
 265         free_page((unsigned long)(kvm->arch.sca));
 266 out_err:
 267         return rc;
 268 }
 269
 270 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 271 {
 272         VCPU_EVENT(vcpu, 3, "%s", "free cpu");
 273         trace_kvm_s390_destroy_vcpu(vcpu->vcpu_id);
 274         if (!kvm_is_ucontrol(vcpu->kvm)) {
 275                 clear_bit(63 - vcpu->vcpu_id,
 276                           (unsigned long *) &vcpu->kvm->arch.sca->mcn);
 277                 if (vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda ==
 278                     (__u64) vcpu->arch.sie_block)
 279                         vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda = 0;
 280         }
 281         smp_mb();
 282
 283         if (kvm_is_ucontrol(vcpu->kvm))
 284                 gmap_free(vcpu->arch.gmap);
 285
 286         free_page((unsigned long)(vcpu->arch.sie_block));
 287         kvm_vcpu_uninit(vcpu);
 288         kmem_cache_free(kvm_vcpu_cache, vcpu);
 289 }
 290
 291 static void kvm_free_vcpus(struct kvm *kvm)
 292 {
 293         unsigned int i;
 294         struct kvm_vcpu *vcpu;
 295
 296         kvm_for_each_vcpu(i, vcpu, kvm)
 297                 kvm_arch_vcpu_destroy(vcpu);
 298
 299         mutex_lock(&kvm->lock);
 300         for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
 301                 kvm->vcpus[i] = NULL;
 302
 303         atomic_set(&kvm->online_vcpus, 0);
 304         mutex_unlock(&kvm->lock);
 305 }
 306
 307 void kvm_arch_sync_events(struct kvm *kvm)
 308 {
 309 }
 310
 311 void kvm_arch_destroy_vm(struct kvm *kvm)
 312 {
 313         kvm_free_vcpus(kvm);
 314         free_page((unsigned long)(kvm->arch.sca));
 315         debug_unregister(kvm->arch.dbf);
 316         if (!kvm_is_ucontrol(kvm))
 317                 gmap_free(kvm->arch.gmap);
 318 }
 319
 320 /* Section: vcpu related */
 321 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 322 {
 323         if (kvm_is_ucontrol(vcpu->kvm)) {
 324                 vcpu->arch.gmap = gmap_alloc(current->mm);
 325                 if (!vcpu->arch.gmap)
 326                         return -ENOMEM;
 327                 vcpu->arch.gmap->private = vcpu->kvm;
 328                 return 0;
 329         }
 330
 331         vcpu->arch.gmap = vcpu->kvm->arch.gmap;
 332         vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX |
 333                                     KVM_SYNC_GPRS |
 334                                     KVM_SYNC_ACRS |
 335                                     KVM_SYNC_CRS;
 336         return 0;
 337 }
 338
 339 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
 340 {
 341         /* Nothing todo */
 342 }
 343
 344 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 345 {
 346         save_fp_ctl(&vcpu->arch.host_fpregs.fpc);
 347         save_fp_regs(vcpu->arch.host_fpregs.fprs);
 348         save_access_regs(vcpu->arch.host_acrs);
 349         restore_fp_ctl(&vcpu->arch.guest_fpregs.fpc);
 350         restore_fp_regs(vcpu->arch.guest_fpregs.fprs);
 351         restore_access_regs(vcpu->run->s.regs.acrs);
 352         gmap_enable(vcpu->arch.gmap);
 353         atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 354 }
 355
 356 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 357 {
 358         atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 359         gmap_disable(vcpu->arch.gmap);
 360         save_fp_ctl(&vcpu->arch.guest_fpregs.fpc);
 361         save_fp_regs(vcpu->arch.guest_fpregs.fprs);
 362         save_access_regs(vcpu->run->s.regs.acrs);
 363         restore_fp_ctl(&vcpu->arch.host_fpregs.fpc);
 364         restore_fp_regs(vcpu->arch.host_fpregs.fprs);
 365         restore_access_regs(vcpu->arch.host_acrs);
 366 }
 367
 368 static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
 369 {
 370         /* this equals initial cpu reset in pop, but we don't switch to ESA */
 371         vcpu->arch.sie_block->gpsw.mask = 0UL;
 372         vcpu->arch.sie_block->gpsw.addr = 0UL;
 373         kvm_s390_set_prefix(vcpu, 0);
 374         vcpu->arch.sie_block->cputm     = 0UL;
 375         vcpu->arch.sie_block->ckc       = 0UL;
 376         vcpu->arch.sie_block->todpr     = 0;
 377         memset(vcpu->arch.sie_block->gcr, 0, 16 * sizeof(__u64));
 378         vcpu->arch.sie_block->gcr[0]  = 0xE0UL;
 379         vcpu->arch.sie_block->gcr[14] = 0xC2000000UL;
 380         vcpu->arch.guest_fpregs.fpc = 0;
 381         asm volatile("lfpc %0" : : "Q" (vcpu->arch.guest_fpregs.fpc));
 382         vcpu->arch.sie_block->gbea = 1;
 383         atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
 384 }
 385
 386 int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 387 {
 388         return 0;
 389 }
 390
 391 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 392 {
 393         atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH |
 394                                                     CPUSTAT_SM |
 395                                                     CPUSTAT_STOPPED |
 396                                                     CPUSTAT_GED);
 397         vcpu->arch.sie_block->ecb   = 6;
 398         if (test_vfacility(50) && test_vfacility(73))
 399                 vcpu->arch.sie_block->ecb |= 0x10;
 400
 401         vcpu->arch.sie_block->ecb2  = 8;
 402         vcpu->arch.sie_block->eca   = 0xC1002001U;
 403         vcpu->arch.sie_block->fac   = (int) (long) vfacilities;
 404         hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
 405         tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet,
 406                      (unsigned long) vcpu);
 407         vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
 408         get_cpu_id(&vcpu->arch.cpu_id);
 409         vcpu->arch.cpu_id.version = 0xff;
 410         return 0;
 411 }
 412
 413 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
 414                                       unsigned int id)
 415 {
 416         struct kvm_vcpu *vcpu;
 417         struct sie_page *sie_page;
 418         int rc = -EINVAL;
 419
 420         if (id >= KVM_MAX_VCPUS)
 421                 goto out;
 422
 423         rc = -ENOMEM;
 424
 425         vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
 426         if (!vcpu)
 427                 goto out;
 428
 429         sie_page = (struct sie_page *) get_zeroed_page(GFP_KERNEL);
 430         if (!sie_page)
 431                 goto out_free_cpu;
 432
 433         vcpu->arch.sie_block = &sie_page->sie_block;
 434         vcpu->arch.sie_block->itdba = (unsigned long) &sie_page->itdb;
 435
 436         vcpu->arch.sie_block->icpua = id;
 437         if (!kvm_is_ucontrol(kvm)) {
 438                 if (!kvm->arch.sca) {
 439                         WARN_ON_ONCE(1);
 440                         goto out_free_cpu;
 441                 }
 442                 if (!kvm->arch.sca->cpu[id].sda)
 443                         kvm->arch.sca->cpu[id].sda =
 444                                 (__u64) vcpu->arch.sie_block;
 445                 vcpu->arch.sie_block->scaoh =
 446                         (__u32)(((__u64)kvm->arch.sca) >> 32);
 447                 vcpu->arch.sie_block->scaol = (__u32)(__u64)kvm->arch.sca;
 448                 set_bit(63 - id, (unsigned long *) &kvm->arch.sca->mcn);
 449         }
 450
 451         spin_lock_init(&vcpu->arch.local_int.lock);
 452         INIT_LIST_HEAD(&vcpu->arch.local_int.list);
 453         vcpu->arch.local_int.float_int = &kvm->arch.float_int;
 454         spin_lock(&kvm->arch.float_int.lock);
 455         kvm->arch.float_int.local_int[id] = &vcpu->arch.local_int;
 456         vcpu->arch.local_int.wq = &vcpu->wq;
 457         vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags;
 458         spin_unlock(&kvm->arch.float_int.lock);
 459
 460         rc = kvm_vcpu_init(vcpu, kvm, id);
 461         if (rc)
 462                 goto out_free_sie_block;
 463         VM_EVENT(kvm, 3, "create cpu %d at %p, sie block at %p", id, vcpu,
 464                  vcpu->arch.sie_block);
 465         trace_kvm_s390_create_vcpu(id, vcpu, vcpu->arch.sie_block);
 466
 467         return vcpu;
 468 out_free_sie_block:
 469         free_page((unsigned long)(vcpu->arch.sie_block));
 470 out_free_cpu:
 471         kmem_cache_free(kvm_vcpu_cache, vcpu);
 472 out:
 473         return ERR_PTR(rc);
 474 }
 475
 476 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
 477 {
 478         /* kvm common code refers to this, but never calls it */
 479         BUG();
 480         return 0;
 481 }
 482
 483 void s390_vcpu_block(struct kvm_vcpu *vcpu)
 484 {
 485         atomic_set_mask(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
 486 }
 487
 488 void s390_vcpu_unblock(struct kvm_vcpu *vcpu)
 489 {
 490         atomic_clear_mask(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
 491 }
 492
 493 /*
 494  * Kick a guest cpu out of SIE and wait until SIE is not running.
 495  * If the CPU is not running (e.g. waiting as idle) the function will
 496  * return immediately. */
 497 void exit_sie(struct kvm_vcpu *vcpu)
 498 {
 499         atomic_set_mask(CPUSTAT_STOP_INT, &vcpu->arch.sie_block->cpuflags);
 500         while (vcpu->arch.sie_block->prog0c & PROG_IN_SIE)
 501                 cpu_relax();
 502 }
 503
 504 /* Kick a guest cpu out of SIE and prevent SIE-reentry */
 505 void exit_sie_sync(struct kvm_vcpu *vcpu)
 506 {
 507         s390_vcpu_block(vcpu);
 508         exit_sie(vcpu);
 509 }
 510
 511 static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address)
 512 {
 513         int i;
 514         struct kvm *kvm = gmap->private;
 515         struct kvm_vcpu *vcpu;
 516
 517         kvm_for_each_vcpu(i, vcpu, kvm) {
 518                 /* match against both prefix pages */
 519                 if (vcpu->arch.sie_block->prefix == (address & ~0x1000UL)) {
 520                         VCPU_EVENT(vcpu, 2, "gmap notifier for %lx", address);
 521                         kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
 522                         exit_sie_sync(vcpu);
 523                 }
 524         }
 525 }
 526
 527 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
 528 {
 529         /* kvm common code refers to this, but never calls it */
 530         BUG();
 531         return 0;
 532 }
 533
 534 static int kvm_arch_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu,
 535                                            struct kvm_one_reg *reg)
 536 {
 537         int r = -EINVAL;
 538
 539         switch (reg->id) {
 540         case KVM_REG_S390_TODPR:
 541                 r = put_user(vcpu->arch.sie_block->todpr,
 542                              (u32 __user *)reg->addr);
 543                 break;
 544         case KVM_REG_S390_EPOCHDIFF:
 545                 r = put_user(vcpu->arch.sie_block->epoch,
 546                              (u64 __user *)reg->addr);
 547                 break;
 548         case KVM_REG_S390_CPU_TIMER:
 549                 r = put_user(vcpu->arch.sie_block->cputm,
 550                              (u64 __user *)reg->addr);
 551                 break;
 552         case KVM_REG_S390_CLOCK_COMP:
 553                 r = put_user(vcpu->arch.sie_block->ckc,
 554                              (u64 __user *)reg->addr);
 555                 break;
 556         default:
 557                 break;
 558         }
 559
 560         return r;
 561 }
 562
 563 static int kvm_arch_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu,
 564                                            struct kvm_one_reg *reg)
 565 {
 566         int r = -EINVAL;
 567
 568         switch (reg->id) {
 569         case KVM_REG_S390_TODPR:
 570                 r = get_user(vcpu->arch.sie_block->todpr,
 571                              (u32 __user *)reg->addr);
 572                 break;
 573         case KVM_REG_S390_EPOCHDIFF:
 574                 r = get_user(vcpu->arch.sie_block->epoch,
 575                              (u64 __user *)reg->addr);
 576                 break;
 577         case KVM_REG_S390_CPU_TIMER:
 578                 r = get_user(vcpu->arch.sie_block->cputm,
 579                              (u64 __user *)reg->addr);
 580                 break;
 581         case KVM_REG_S390_CLOCK_COMP:
 582                 r = get_user(vcpu->arch.sie_block->ckc,
 583                              (u64 __user *)reg->addr);
 584                 break;
 585         default:
 586                 break;
 587         }
 588
 589         return r;
 590 }
 591
 592 static int kvm_arch_vcpu_ioctl_initial_reset(struct kvm_vcpu *vcpu)
 593 {
 594         kvm_s390_vcpu_initial_reset(vcpu);
 595         return 0;
 596 }
 597
 598 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 599 {
 600         memcpy(&vcpu->run->s.regs.gprs, &regs->gprs, sizeof(regs->gprs));
 601         return 0;
 602 }
 603
 604 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 605 {
 606         memcpy(&regs->gprs, &vcpu->run->s.regs.gprs, sizeof(regs->gprs));
 607         return 0;
 608 }
 609
 610 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 611                                   struct kvm_sregs *sregs)
 612 {
 613         memcpy(&vcpu->run->s.regs.acrs, &sregs->acrs, sizeof(sregs->acrs));
 614         memcpy(&vcpu->arch.sie_block->gcr, &sregs->crs, sizeof(sregs->crs));
 615         restore_access_regs(vcpu->run->s.regs.acrs);
 616         return 0;
 617 }
 618
 619 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 620                                   struct kvm_sregs *sregs)
 621 {
 622         memcpy(&sregs->acrs, &vcpu->run->s.regs.acrs, sizeof(sregs->acrs));
 623         memcpy(&sregs->crs, &vcpu->arch.sie_block->gcr, sizeof(sregs->crs));
 624         return 0;
 625 }
 626
 627 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 628 {
 629         if (test_fp_ctl(fpu->fpc))
 630                 return -EINVAL;
 631         memcpy(&vcpu->arch.guest_fpregs.fprs, &fpu->fprs, sizeof(fpu->fprs));
 632         vcpu->arch.guest_fpregs.fpc = fpu->fpc;
 633         restore_fp_ctl(&vcpu->arch.guest_fpregs.fpc);
 634         restore_fp_regs(vcpu->arch.guest_fpregs.fprs);
 635         return 0;
 636 }
 637
 638 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 639 {
 640         memcpy(&fpu->fprs, &vcpu->arch.guest_fpregs.fprs, sizeof(fpu->fprs));
 641         fpu->fpc = vcpu->arch.guest_fpregs.fpc;
 642         return 0;
 643 }
 644
 645 static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw)
 646 {
 647         int rc = 0;
 648
 649         if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED))
 650                 rc = -EBUSY;
 651         else {
 652                 vcpu->run->psw_mask = psw.mask;
 653                 vcpu->run->psw_addr = psw.addr;
 654         }
 655         return rc;
 656 }
 657
 658 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 659                                   struct kvm_translation *tr)
 660 {
 661         return -EINVAL; /* not implemented yet */
 662 }
 663
 664 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 665                                         struct kvm_guest_debug *dbg)
 666 {
 667         return -EINVAL; /* not implemented yet */
 668 }
 669
 670 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 671                                     struct kvm_mp_state *mp_state)
 672 {
 673         return -EINVAL; /* not implemented yet */
 674 }
 675
 676 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 677                                     struct kvm_mp_state *mp_state)
 678 {
 679         return -EINVAL; /* not implemented yet */
 680 }
 681
 682 static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu)
 683 {
 684         /*
 685          * We use MMU_RELOAD just to re-arm the ipte notifier for the
 686          * guest prefix page. gmap_ipte_notify will wait on the ptl lock.
 687          * This ensures that the ipte instruction for this request has
 688          * already finished. We might race against a second unmapper that
 689          * wants to set the blocking bit. Lets just retry the request loop.
 690          */
 691         while (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) {
 692                 int rc;
 693                 rc = gmap_ipte_notify(vcpu->arch.gmap,
 694                                       vcpu->arch.sie_block->prefix,
 695                                       PAGE_SIZE * 2);
 696                 if (rc)
 697                         return rc;
 698                 s390_vcpu_unblock(vcpu);
 699         }
 700         return 0;
 701 }
 702
 703 static int vcpu_pre_run(struct kvm_vcpu *vcpu)
 704 {
 705         int rc, cpuflags;
 706
 707         memcpy(&vcpu->arch.sie_block->gg14, &vcpu->run->s.regs.gprs[14], 16);
 708
 709         if (need_resched())
 710                 schedule();
 711
 712         if (test_thread_flag(TIF_MCCK_PENDING))
 713                 s390_handle_mcck();
 714
 715         if (!kvm_is_ucontrol(vcpu->kvm))
 716                 kvm_s390_deliver_pending_interrupts(vcpu);
 717
 718         rc = kvm_s390_handle_requests(vcpu);
 719         if (rc)
 720                 return rc;
 721
 722         vcpu->arch.sie_block->icptcode = 0;
 723         cpuflags = atomic_read(&vcpu->arch.sie_block->cpuflags);
 724         VCPU_EVENT(vcpu, 6, "entering sie flags %x", cpuflags);
 725         trace_kvm_s390_sie_enter(vcpu, cpuflags);
 726
 727         return 0;
 728 }
 729
 730 static int vcpu_post_run(struct kvm_vcpu *vcpu, int exit_reason)
 731 {
 732         int rc;
 733
 734         VCPU_EVENT(vcpu, 6, "exit sie icptcode %d",
 735                    vcpu->arch.sie_block->icptcode);
 736         trace_kvm_s390_sie_exit(vcpu, vcpu->arch.sie_block->icptcode);
 737
 738         if (exit_reason >= 0) {
 739                 rc = 0;
 740         } else if (kvm_is_ucontrol(vcpu->kvm)) {
 741                 vcpu->run->exit_reason = KVM_EXIT_S390_UCONTROL;
 742                 vcpu->run->s390_ucontrol.trans_exc_code =
 743                                                 current->thread.gmap_addr;
 744                 vcpu->run->s390_ucontrol.pgm_code = 0x10;
 745                 rc = -EREMOTE;
 746         } else {
 747                 VCPU_EVENT(vcpu, 3, "%s", "fault in sie instruction");
 748                 trace_kvm_s390_sie_fault(vcpu);
 749                 rc = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
 750         }
 751
 752         memcpy(&vcpu->run->s.regs.gprs[14], &vcpu->arch.sie_block->gg14, 16);
 753
 754         if (rc == 0) {
 755                 if (kvm_is_ucontrol(vcpu->kvm))
 756                         rc = -EOPNOTSUPP;
 757                 else
 758                         rc = kvm_handle_sie_intercept(vcpu);
 759         }
 760
 761         return rc;
 762 }
 763
 764 static int __vcpu_run(struct kvm_vcpu *vcpu)
 765 {
 766         int rc, exit_reason;
 767
 768         /*
 769          * We try to hold kvm->srcu during most of vcpu_run (except when run-
 770          * ning the guest), so that memslots (and other stuff) are protected
 771          */
 772         vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 773
 774         do {
 775                 rc = vcpu_pre_run(vcpu);
 776                 if (rc)
 777                         break;
 778
 779                 srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 780                 /*
 781                  * As PF_VCPU will be used in fault handler, between
 782                  * guest_enter and guest_exit should be no uaccess.
 783                  */
 784                 preempt_disable();
 785                 kvm_guest_enter();
 786                 preempt_enable();
 787                 exit_reason = sie64a(vcpu->arch.sie_block,
 788                                      vcpu->run->s.regs.gprs);
 789                 kvm_guest_exit();
 790                 vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 791
 792                 rc = vcpu_post_run(vcpu, exit_reason);
 793         } while (!signal_pending(current) && !rc);
 794
 795         srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
 796         return rc;
 797 }
 798
 799 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 800 {
 801         int rc;
 802         sigset_t sigsaved;
 803
 804         if (vcpu->sigset_active)
 805                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 806
 807         atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
 808
 809         BUG_ON(vcpu->kvm->arch.float_int.local_int[vcpu->vcpu_id] == NULL);
 810
 811         switch (kvm_run->exit_reason) {
 812         case KVM_EXIT_S390_SIEIC:
 813         case KVM_EXIT_UNKNOWN:
 814         case KVM_EXIT_INTR:
 815         case KVM_EXIT_S390_RESET:
 816         case KVM_EXIT_S390_UCONTROL:
 817         case KVM_EXIT_S390_TSCH:
 818                 break;
 819         default:
 820                 BUG();
 821         }
 822
 823         vcpu->arch.sie_block->gpsw.mask = kvm_run->psw_mask;
 824         vcpu->arch.sie_block->gpsw.addr = kvm_run->psw_addr;
 825         if (kvm_run->kvm_dirty_regs & KVM_SYNC_PREFIX) {
 826                 kvm_run->kvm_dirty_regs &= ~KVM_SYNC_PREFIX;
 827                 kvm_s390_set_prefix(vcpu, kvm_run->s.regs.prefix);
 828         }
 829         if (kvm_run->kvm_dirty_regs & KVM_SYNC_CRS) {
 830                 kvm_run->kvm_dirty_regs &= ~KVM_SYNC_CRS;
 831                 memcpy(&vcpu->arch.sie_block->gcr, &kvm_run->s.regs.crs, 128);
 832                 kvm_s390_set_prefix(vcpu, kvm_run->s.regs.prefix);
 833         }
 834
 835         might_fault();
 836         rc = __vcpu_run(vcpu);
 837
 838         if (signal_pending(current) && !rc) {
 839                 kvm_run->exit_reason = KVM_EXIT_INTR;
 840                 rc = -EINTR;
 841         }
 842
 843         if (rc == -EOPNOTSUPP) {
 844                 /* intercept cannot be handled in-kernel, prepare kvm-run */
 845                 kvm_run->exit_reason         = KVM_EXIT_S390_SIEIC;
 846                 kvm_run->s390_sieic.icptcode = vcpu->arch.sie_block->icptcode;
 847                 kvm_run->s390_sieic.ipa      = vcpu->arch.sie_block->ipa;
 848                 kvm_run->s390_sieic.ipb      = vcpu->arch.sie_block->ipb;
 849                 rc = 0;
 850         }
 851
 852         if (rc == -EREMOTE) {
 853                 /* intercept was handled, but userspace support is needed
 854                  * kvm_run has been prepared by the handler */
 855                 rc = 0;
 856         }
 857
 858         kvm_run->psw_mask     = vcpu->arch.sie_block->gpsw.mask;
 859         kvm_run->psw_addr     = vcpu->arch.sie_block->gpsw.addr;
 860         kvm_run->s.regs.prefix = vcpu->arch.sie_block->prefix;
 861         memcpy(&kvm_run->s.regs.crs, &vcpu->arch.sie_block->gcr, 128);
 862
 863         if (vcpu->sigset_active)
 864                 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
 865
 866         vcpu->stat.exit_userspace++;
 867         return rc;
 868 }
 869
 870 static int __guestcopy(struct kvm_vcpu *vcpu, u64 guestdest, void *from,
 871                        unsigned long n, int prefix)
 872 {
 873         if (prefix)
 874                 return copy_to_guest(vcpu, guestdest, from, n);
 875         else
 876                 return copy_to_guest_absolute(vcpu, guestdest, from, n);
 877 }
 878
 879 /*
 880  * store status at address
 881  * we use have two special cases:
 882  * KVM_S390_STORE_STATUS_NOADDR: -> 0x1200 on 64 bit
 883  * KVM_S390_STORE_STATUS_PREFIXED: -> prefix
 884  */
 885 int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long addr)
 886 {
 887         unsigned char archmode = 1;
 888         int prefix;
 889         u64 clkcomp;
 890
 891         if (addr == KVM_S390_STORE_STATUS_NOADDR) {
 892                 if (copy_to_guest_absolute(vcpu, 163ul, &archmode, 1))
 893                         return -EFAULT;
 894                 addr = SAVE_AREA_BASE;
 895                 prefix = 0;
 896         } else if (addr == KVM_S390_STORE_STATUS_PREFIXED) {
 897                 if (copy_to_guest(vcpu, 163ul, &archmode, 1))
 898                         return -EFAULT;
 899                 addr = SAVE_AREA_BASE;
 900                 prefix = 1;
 901         } else
 902                 prefix = 0;
 903
 904         if (__guestcopy(vcpu, addr + offsetof(struct save_area, fp_regs),
 905                         vcpu->arch.guest_fpregs.fprs, 128, prefix))
 906                 return -EFAULT;
 907
 908         if (__guestcopy(vcpu, addr + offsetof(struct save_area, gp_regs),
 909                         vcpu->run->s.regs.gprs, 128, prefix))
 910                 return -EFAULT;
 911
 912         if (__guestcopy(vcpu, addr + offsetof(struct save_area, psw),
 913                         &vcpu->arch.sie_block->gpsw, 16, prefix))
 914                 return -EFAULT;
 915
 916         if (__guestcopy(vcpu, addr + offsetof(struct save_area, pref_reg),
 917                         &vcpu->arch.sie_block->prefix, 4, prefix))
 918                 return -EFAULT;
 919
 920         if (__guestcopy(vcpu,
 921                         addr + offsetof(struct save_area, fp_ctrl_reg),
 922                         &vcpu->arch.guest_fpregs.fpc, 4, prefix))
 923                 return -EFAULT;
 924
 925         if (__guestcopy(vcpu, addr + offsetof(struct save_area, tod_reg),
 926                         &vcpu->arch.sie_block->todpr, 4, prefix))
 927                 return -EFAULT;
 928
 929         if (__guestcopy(vcpu, addr + offsetof(struct save_area, timer),
 930                         &vcpu->arch.sie_block->cputm, 8, prefix))
 931                 return -EFAULT;
 932
 933         clkcomp = vcpu->arch.sie_block->ckc >> 8;
 934         if (__guestcopy(vcpu, addr + offsetof(struct save_area, clk_cmp),
 935                         &clkcomp, 8, prefix))
 936                 return -EFAULT;
 937
 938         if (__guestcopy(vcpu, addr + offsetof(struct save_area, acc_regs),
 939                         &vcpu->run->s.regs.acrs, 64, prefix))
 940                 return -EFAULT;
 941
 942         if (__guestcopy(vcpu,
 943                         addr + offsetof(struct save_area, ctrl_regs),
 944                         &vcpu->arch.sie_block->gcr, 128, prefix))
 945                 return -EFAULT;
 946         return 0;
 947 }
 948
 949 int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr)
 950 {
 951         /*
 952          * The guest FPRS and ACRS are in the host FPRS/ACRS due to the lazy
 953          * copying in vcpu load/put. Lets update our copies before we save
 954          * it into the save area
 955          */
 956         save_fp_ctl(&vcpu->arch.guest_fpregs.fpc);
 957         save_fp_regs(vcpu->arch.guest_fpregs.fprs);
 958         save_access_regs(vcpu->run->s.regs.acrs);
 959
 960         return kvm_s390_store_status_unloaded(vcpu, addr);
 961 }
 962
 963 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
 964                                      struct kvm_enable_cap *cap)
 965 {
 966         int r;
 967
 968         if (cap->flags)
 969                 return -EINVAL;
 970
 971         switch (cap->cap) {
 972         case KVM_CAP_S390_CSS_SUPPORT:
 973                 if (!vcpu->kvm->arch.css_support) {
 974                         vcpu->kvm->arch.css_support = 1;
 975                         trace_kvm_s390_enable_css(vcpu->kvm);
 976                 }
 977                 r = 0;
 978                 break;
 979         default:
 980                 r = -EINVAL;
 981                 break;
 982         }
 983         return r;
 984 }
 985
 986 long kvm_arch_vcpu_ioctl(struct file *filp,
 987                          unsigned int ioctl, unsigned long arg)
 988 {
 989         struct kvm_vcpu *vcpu = filp->private_data;
 990         void __user *argp = (void __user *)arg;
 991         int idx;
 992         long r;
 993
 994         switch (ioctl) {
 995         case KVM_S390_INTERRUPT: {
 996                 struct kvm_s390_interrupt s390int;
 997
 998                 r = -EFAULT;
 999                 if (copy_from_user(&s390int, argp, sizeof(s390int)))
1000                         break;
1001                 r = kvm_s390_inject_vcpu(vcpu, &s390int);
1002                 break;
1003         }
1004         case KVM_S390_STORE_STATUS:
1005                 idx = srcu_read_lock(&vcpu->kvm->srcu);
1006                 r = kvm_s390_vcpu_store_status(vcpu, arg);
1007                 srcu_read_unlock(&vcpu->kvm->srcu, idx);
1008                 break;
1009         case KVM_S390_SET_INITIAL_PSW: {
1010                 psw_t psw;
1011
1012                 r = -EFAULT;
1013                 if (copy_from_user(&psw, argp, sizeof(psw)))
1014                         break;
1015                 r = kvm_arch_vcpu_ioctl_set_initial_psw(vcpu, psw);
1016                 break;
1017         }
1018         case KVM_S390_INITIAL_RESET:
1019                 r = kvm_arch_vcpu_ioctl_initial_reset(vcpu);
1020                 break;
1021         case KVM_SET_ONE_REG:
1022         case KVM_GET_ONE_REG: {
1023                 struct kvm_one_reg reg;
1024                 r = -EFAULT;
1025                 if (copy_from_user(&reg, argp, sizeof(reg)))
1026                         break;
1027                 if (ioctl == KVM_SET_ONE_REG)
1028                         r = kvm_arch_vcpu_ioctl_set_one_reg(vcpu, &reg);
1029                 else
1030                         r = kvm_arch_vcpu_ioctl_get_one_reg(vcpu, &reg);
1031                 break;
1032         }
1033 #ifdef CONFIG_KVM_S390_UCONTROL
1034         case KVM_S390_UCAS_MAP: {
1035                 struct kvm_s390_ucas_mapping ucasmap;
1036
1037                 if (copy_from_user(&ucasmap, argp, sizeof(ucasmap))) {
1038                         r = -EFAULT;
1039                         break;
1040                 }
1041
1042                 if (!kvm_is_ucontrol(vcpu->kvm)) {
1043                         r = -EINVAL;
1044                         break;
1045                 }
1046
1047                 r = gmap_map_segment(vcpu->arch.gmap, ucasmap.user_addr,
1048                                      ucasmap.vcpu_addr, ucasmap.length);
1049                 break;
1050         }
1051         case KVM_S390_UCAS_UNMAP: {
1052                 struct kvm_s390_ucas_mapping ucasmap;
1053
1054                 if (copy_from_user(&ucasmap, argp, sizeof(ucasmap))) {
1055                         r = -EFAULT;
1056                         break;
1057                 }
1058
1059                 if (!kvm_is_ucontrol(vcpu->kvm)) {
1060                         r = -EINVAL;
1061                         break;
1062                 }
1063
1064                 r = gmap_unmap_segment(vcpu->arch.gmap, ucasmap.vcpu_addr,
1065                         ucasmap.length);
1066                 break;
1067         }
1068 #endif
1069         case KVM_S390_VCPU_FAULT: {
1070                 r = gmap_fault(arg, vcpu->arch.gmap);
1071                 if (!IS_ERR_VALUE(r))
1072                         r = 0;
1073                 break;
1074         }
1075         case KVM_ENABLE_CAP:
1076         {
1077                 struct kvm_enable_cap cap;
1078                 r = -EFAULT;
1079                 if (copy_from_user(&cap, argp, sizeof(cap)))
1080                         break;
1081                 r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
1082                 break;
1083         }
1084         default:
1085                 r = -ENOTTY;
1086         }
1087         return r;
1088 }
1089
1090 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1091 {
1092 #ifdef CONFIG_KVM_S390_UCONTROL
1093         if ((vmf->pgoff == KVM_S390_SIE_PAGE_OFFSET)
1094                  && (kvm_is_ucontrol(vcpu->kvm))) {
1095                 vmf->page = virt_to_page(vcpu->arch.sie_block);
1096                 get_page(vmf->page);
1097                 return 0;
1098         }
1099 #endif
1100         return VM_FAULT_SIGBUS;
1101 }
1102
1103 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
1104                            struct kvm_memory_slot *dont)
1105 {
1106 }
1107
1108 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
1109                             unsigned long npages)
1110 {
1111         return 0;
1112 }
1113
1114 void kvm_arch_memslots_updated(struct kvm *kvm)
1115 {
1116 }
1117
1118 /* Section: memory related */
1119 int kvm_arch_prepare_memory_region(struct kvm *kvm,
1120                                    struct kvm_memory_slot *memslot,
1121                                    struct kvm_userspace_memory_region *mem,
1122                                    enum kvm_mr_change change)
1123 {
1124         /* A few sanity checks. We can have memory slots which have to be
1125            located/ended at a segment boundary (1MB). The memory in userland is
1126            ok to be fragmented into various different vmas. It is okay to mmap()
1127            and munmap() stuff in this slot after doing this call at any time */
1128
1129         if (mem->userspace_addr & 0xffffful)
1130                 return -EINVAL;
1131
1132         if (mem->memory_size & 0xffffful)
1133                 return -EINVAL;
1134
1135         return 0;
1136 }
1137
1138 void kvm_arch_commit_memory_region(struct kvm *kvm,
1139                                 struct kvm_userspace_memory_region *mem,
1140                                 const struct kvm_memory_slot *old,
1141                                 enum kvm_mr_change change)
1142 {
1143         int rc;
1144
1145         /* If the basics of the memslot do not change, we do not want
1146          * to update the gmap. Every update causes several unnecessary
1147          * segment translation exceptions. This is usually handled just
1148          * fine by the normal fault handler + gmap, but it will also
1149          * cause faults on the prefix page of running guest CPUs.
1150          */
1151         if (old->userspace_addr == mem->userspace_addr &&
1152             old->base_gfn * PAGE_SIZE == mem->guest_phys_addr &&
1153             old->npages * PAGE_SIZE == mem->memory_size)
1154                 return;
1155
1156         rc = gmap_map_segment(kvm->arch.gmap, mem->userspace_addr,
1157                 mem->guest_phys_addr, mem->memory_size);
1158         if (rc)
1159                 printk(KERN_WARNING "kvm-s390: failed to commit memory region\n");
1160         return;
1161 }
1162
1163 void kvm_arch_flush_shadow_all(struct kvm *kvm)
1164 {
1165 }
1166
1167 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
1168                                    struct kvm_memory_slot *slot)
1169 {
1170 }
1171
1172 static int __init kvm_s390_init(void)
1173 {
1174         int ret;
1175         ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1176         if (ret)
1177                 return ret;
1178
1179         /*
1180          * guests can ask for up to 255+1 double words, we need a full page
1181          * to hold the maximum amount of facilities. On the other hand, we
1182          * only set facilities that are known to work in KVM.
1183          */
1184         vfacilities = (unsigned long *) get_zeroed_page(GFP_KERNEL|GFP_DMA);
1185         if (!vfacilities) {
1186                 kvm_exit();
1187                 return -ENOMEM;
1188         }
1189         memcpy(vfacilities, S390_lowcore.stfle_fac_list, 16);
1190         vfacilities[0] &= 0xff82fff3f4fc2000UL;
1191         vfacilities[1] &= 0x005c000000000000UL;
1192         return 0;
1193 }
1194
1195 static void __exit kvm_s390_exit(void)
1196 {
1197         free_page((unsigned long) vfacilities);
1198         kvm_exit();
1199 }
1200
1201 module_init(kvm_s390_init);
1202 module_exit(kvm_s390_exit);
1203
1204 /*
1205  * Enable autoloading of the kvm module.
1206  * Note that we add the module alias here instead of virt/kvm/kvm_main.c
1207  * since x86 takes a different approach.
1208  */
1209 #include <linux/miscdevice.h>
1210 MODULE_ALIAS_MISCDEV(KVM_MINOR);
1211 MODULE_ALIAS("devname:kvm");