arch/powerpc/kvm/powerpc.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2, as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program; if not, write to the Free Software
  13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  14  *
  15  * Copyright IBM Corp. 2007
  16  *
  17  * Authors: Hollis Blanchard <hollisb@us.ibm.com>
  18  *          Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
  19  */
  20
  21 #include <linux/errno.h>
  22 #include <linux/err.h>
  23 #include <linux/kvm_host.h>
  24 #include <linux/module.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/fs.h>
  27 #include <asm/cputable.h>
  28 #include <asm/uaccess.h>
  29 #include <asm/kvm_ppc.h>
  30 #include <asm/tlbflush.h>
  31
  32
  33 gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
  34 {
  35         return gfn;
  36 }
  37
  38 int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
  39 {
  40         return !!(v->arch.pending_exceptions);
  41 }
  42
  43 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
  44 {
  45         return !(v->arch.msr & MSR_WE);
  46 }
  47
  48
  49 int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu)
  50 {
  51         enum emulation_result er;
  52         int r;
  53
  54         er = kvmppc_emulate_instruction(run, vcpu);
  55         switch (er) {
  56         case EMULATE_DONE:
  57                 /* Future optimization: only reload non-volatiles if they were
  58                  * actually modified. */
  59                 r = RESUME_GUEST_NV;
  60                 break;
  61         case EMULATE_DO_MMIO:
  62                 run->exit_reason = KVM_EXIT_MMIO;
  63                 /* We must reload nonvolatiles because "update" load/store
  64                  * instructions modify register state. */
  65                 /* Future optimization: only reload non-volatiles if they were
  66                  * actually modified. */
  67                 r = RESUME_HOST_NV;
  68                 break;
  69         case EMULATE_FAIL:
  70                 /* XXX Deliver Program interrupt to guest. */
  71                 printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__,
  72                        vcpu->arch.last_inst);
  73                 r = RESUME_HOST;
  74                 break;
  75         default:
  76                 BUG();
  77         }
  78
  79         return r;
  80 }
  81
  82 void kvm_arch_hardware_enable(void *garbage)
  83 {
  84 }
  85
  86 void kvm_arch_hardware_disable(void *garbage)
  87 {
  88 }
  89
  90 int kvm_arch_hardware_setup(void)
  91 {
  92         return 0;
  93 }
  94
  95 void kvm_arch_hardware_unsetup(void)
  96 {
  97 }
  98
  99 void kvm_arch_check_processor_compat(void *rtn)
 100 {
 101         int r;
 102
 103         if (strcmp(cur_cpu_spec->platform, "ppc440") == 0)
 104                 r = 0;
 105         else
 106                 r = -ENOTSUPP;
 107
 108         *(int *)rtn = r;
 109 }
 110
 111 struct kvm *kvm_arch_create_vm(void)
 112 {
 113         struct kvm *kvm;
 114
 115         kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
 116         if (!kvm)
 117                 return ERR_PTR(-ENOMEM);
 118
 119         return kvm;
 120 }
 121
 122 static void kvmppc_free_vcpus(struct kvm *kvm)
 123 {
 124         unsigned int i;
 125
 126         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 127                 if (kvm->vcpus[i]) {
 128                         kvm_arch_vcpu_free(kvm->vcpus[i]);
 129                         kvm->vcpus[i] = NULL;
 130                 }
 131         }
 132 }
 133
 134 void kvm_arch_destroy_vm(struct kvm *kvm)
 135 {
 136         kvmppc_free_vcpus(kvm);
 137         kvm_free_physmem(kvm);
 138         kfree(kvm);
 139 }
 140
 141 int kvm_dev_ioctl_check_extension(long ext)
 142 {
 143         int r;
 144
 145         switch (ext) {
 146         case KVM_CAP_USER_MEMORY:
 147                 r = 1;
 148                 break;
 149         case KVM_CAP_COALESCED_MMIO:
 150                 r = KVM_COALESCED_MMIO_PAGE_OFFSET;
 151                 break;
 152         default:
 153                 r = 0;
 154                 break;
 155         }
 156         return r;
 157
 158 }
 159
 160 long kvm_arch_dev_ioctl(struct file *filp,
 161                         unsigned int ioctl, unsigned long arg)
 162 {
 163         return -EINVAL;
 164 }
 165
 166 int kvm_arch_set_memory_region(struct kvm *kvm,
 167                                struct kvm_userspace_memory_region *mem,
 168                                struct kvm_memory_slot old,
 169                                int user_alloc)
 170 {
 171         return 0;
 172 }
 173
 174 void kvm_arch_flush_shadow(struct kvm *kvm)
 175 {
 176 }
 177
 178 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 179 {
 180         struct kvm_vcpu *vcpu;
 181         int err;
 182
 183         vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
 184         if (!vcpu) {
 185                 err = -ENOMEM;
 186                 goto out;
 187         }
 188
 189         err = kvm_vcpu_init(vcpu, kvm, id);
 190         if (err)
 191                 goto free_vcpu;
 192
 193         return vcpu;
 194
 195 free_vcpu:
 196         kmem_cache_free(kvm_vcpu_cache, vcpu);
 197 out:
 198         return ERR_PTR(err);
 199 }
 200
 201 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 202 {
 203         kvm_vcpu_uninit(vcpu);
 204         kmem_cache_free(kvm_vcpu_cache, vcpu);
 205 }
 206
 207 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 208 {
 209         kvm_arch_vcpu_free(vcpu);
 210 }
 211
 212 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 213 {
 214         unsigned int priority = exception_priority[BOOKE_INTERRUPT_DECREMENTER];
 215
 216         return test_bit(priority, &vcpu->arch.pending_exceptions);
 217 }
 218
 219 static void kvmppc_decrementer_func(unsigned long data)
 220 {
 221         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
 222
 223         kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_DECREMENTER);
 224
 225         if (waitqueue_active(&vcpu->wq)) {
 226                 wake_up_interruptible(&vcpu->wq);
 227                 vcpu->stat.halt_wakeup++;
 228         }
 229 }
 230
 231 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 232 {
 233         setup_timer(&vcpu->arch.dec_timer, kvmppc_decrementer_func,
 234                     (unsigned long)vcpu);
 235
 236         return 0;
 237 }
 238
 239 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
 240 {
 241 }
 242
 243 /* Note: clearing MSR[DE] just means that the debug interrupt will not be
 244  * delivered *immediately*. Instead, it simply sets the appropriate DBSR bits.
 245  * If those DBSR bits are still set when MSR[DE] is re-enabled, the interrupt
 246  * will be delivered as an "imprecise debug event" (which is indicated by
 247  * DBSR[IDE].
 248  */
 249 static void kvmppc_disable_debug_interrupts(void)
 250 {
 251         mtmsr(mfmsr() & ~MSR_DE);
 252 }
 253
 254 static void kvmppc_restore_host_debug_state(struct kvm_vcpu *vcpu)
 255 {
 256         kvmppc_disable_debug_interrupts();
 257
 258         mtspr(SPRN_IAC1, vcpu->arch.host_iac[0]);
 259         mtspr(SPRN_IAC2, vcpu->arch.host_iac[1]);
 260         mtspr(SPRN_IAC3, vcpu->arch.host_iac[2]);
 261         mtspr(SPRN_IAC4, vcpu->arch.host_iac[3]);
 262         mtspr(SPRN_DBCR1, vcpu->arch.host_dbcr1);
 263         mtspr(SPRN_DBCR2, vcpu->arch.host_dbcr2);
 264         mtspr(SPRN_DBCR0, vcpu->arch.host_dbcr0);
 265         mtmsr(vcpu->arch.host_msr);
 266 }
 267
 268 static void kvmppc_load_guest_debug_registers(struct kvm_vcpu *vcpu)
 269 {
 270         struct kvm_guest_debug *dbg = &vcpu->guest_debug;
 271         u32 dbcr0 = 0;
 272
 273         vcpu->arch.host_msr = mfmsr();
 274         kvmppc_disable_debug_interrupts();
 275
 276         /* Save host debug register state. */
 277         vcpu->arch.host_iac[0] = mfspr(SPRN_IAC1);
 278         vcpu->arch.host_iac[1] = mfspr(SPRN_IAC2);
 279         vcpu->arch.host_iac[2] = mfspr(SPRN_IAC3);
 280         vcpu->arch.host_iac[3] = mfspr(SPRN_IAC4);
 281         vcpu->arch.host_dbcr0 = mfspr(SPRN_DBCR0);
 282         vcpu->arch.host_dbcr1 = mfspr(SPRN_DBCR1);
 283         vcpu->arch.host_dbcr2 = mfspr(SPRN_DBCR2);
 284
 285         /* set registers up for guest */
 286
 287         if (dbg->bp[0]) {
 288                 mtspr(SPRN_IAC1, dbg->bp[0]);
 289                 dbcr0 |= DBCR0_IAC1 | DBCR0_IDM;
 290         }
 291         if (dbg->bp[1]) {
 292                 mtspr(SPRN_IAC2, dbg->bp[1]);
 293                 dbcr0 |= DBCR0_IAC2 | DBCR0_IDM;
 294         }
 295         if (dbg->bp[2]) {
 296                 mtspr(SPRN_IAC3, dbg->bp[2]);
 297                 dbcr0 |= DBCR0_IAC3 | DBCR0_IDM;
 298         }
 299         if (dbg->bp[3]) {
 300                 mtspr(SPRN_IAC4, dbg->bp[3]);
 301                 dbcr0 |= DBCR0_IAC4 | DBCR0_IDM;
 302         }
 303
 304         mtspr(SPRN_DBCR0, dbcr0);
 305         mtspr(SPRN_DBCR1, 0);
 306         mtspr(SPRN_DBCR2, 0);
 307 }
 308
 309 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 310 {
 311         int i;
 312
 313         if (vcpu->guest_debug.enabled)
 314                 kvmppc_load_guest_debug_registers(vcpu);
 315
 316         /* Mark every guest entry in the shadow TLB entry modified, so that they
 317          * will all be reloaded on the next vcpu run (instead of being
 318          * demand-faulted). */
 319         for (i = 0; i <= tlb_44x_hwater; i++)
 320                 kvmppc_tlbe_set_modified(vcpu, i);
 321 }
 322
 323 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 324 {
 325         if (vcpu->guest_debug.enabled)
 326                 kvmppc_restore_host_debug_state(vcpu);
 327
 328         /* Don't leave guest TLB entries resident when being de-scheduled. */
 329         /* XXX It would be nice to differentiate between heavyweight exit and
 330          * sched_out here, since we could avoid the TLB flush for heavyweight
 331          * exits. */
 332         _tlbia();
 333 }
 334
 335 int kvm_arch_vcpu_ioctl_debug_guest(struct kvm_vcpu *vcpu,
 336                                     struct kvm_debug_guest *dbg)
 337 {
 338         int i;
 339
 340         vcpu->guest_debug.enabled = dbg->enabled;
 341         if (vcpu->guest_debug.enabled) {
 342                 for (i=0; i < ARRAY_SIZE(vcpu->guest_debug.bp); i++) {
 343                         if (dbg->breakpoints[i].enabled)
 344                                 vcpu->guest_debug.bp[i] = dbg->breakpoints[i].address;
 345                         else
 346                                 vcpu->guest_debug.bp[i] = 0;
 347                 }
 348         }
 349
 350         return 0;
 351 }
 352
 353 static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
 354                                      struct kvm_run *run)
 355 {
 356         u32 *gpr = &vcpu->arch.gpr[vcpu->arch.io_gpr];
 357         *gpr = run->dcr.data;
 358 }
 359
 360 static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
 361                                       struct kvm_run *run)
 362 {
 363         u32 *gpr = &vcpu->arch.gpr[vcpu->arch.io_gpr];
 364
 365         if (run->mmio.len > sizeof(*gpr)) {
 366                 printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
 367                 return;
 368         }
 369
 370         if (vcpu->arch.mmio_is_bigendian) {
 371                 switch (run->mmio.len) {
 372                 case 4: *gpr = *(u32 *)run->mmio.data; break;
 373                 case 2: *gpr = *(u16 *)run->mmio.data; break;
 374                 case 1: *gpr = *(u8 *)run->mmio.data; break;
 375                 }
 376         } else {
 377                 /* Convert BE data from userland back to LE. */
 378                 switch (run->mmio.len) {
 379                 case 4: *gpr = ld_le32((u32 *)run->mmio.data); break;
 380                 case 2: *gpr = ld_le16((u16 *)run->mmio.data); break;
 381                 case 1: *gpr = *(u8 *)run->mmio.data; break;
 382                 }
 383         }
 384 }
 385
 386 int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
 387                        unsigned int rt, unsigned int bytes, int is_bigendian)
 388 {
 389         if (bytes > sizeof(run->mmio.data)) {
 390                 printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
 391                        run->mmio.len);
 392         }
 393
 394         run->mmio.phys_addr = vcpu->arch.paddr_accessed;
 395         run->mmio.len = bytes;
 396         run->mmio.is_write = 0;
 397
 398         vcpu->arch.io_gpr = rt;
 399         vcpu->arch.mmio_is_bigendian = is_bigendian;
 400         vcpu->mmio_needed = 1;
 401         vcpu->mmio_is_write = 0;
 402
 403         return EMULATE_DO_MMIO;
 404 }
 405
 406 int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
 407                         u32 val, unsigned int bytes, int is_bigendian)
 408 {
 409         void *data = run->mmio.data;
 410
 411         if (bytes > sizeof(run->mmio.data)) {
 412                 printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
 413                        run->mmio.len);
 414         }
 415
 416         run->mmio.phys_addr = vcpu->arch.paddr_accessed;
 417         run->mmio.len = bytes;
 418         run->mmio.is_write = 1;
 419         vcpu->mmio_needed = 1;
 420         vcpu->mmio_is_write = 1;
 421
 422         /* Store the value at the lowest bytes in 'data'. */
 423         if (is_bigendian) {
 424                 switch (bytes) {
 425                 case 4: *(u32 *)data = val; break;
 426                 case 2: *(u16 *)data = val; break;
 427                 case 1: *(u8  *)data = val; break;
 428                 }
 429         } else {
 430                 /* Store LE value into 'data'. */
 431                 switch (bytes) {
 432                 case 4: st_le32(data, val); break;
 433                 case 2: st_le16(data, val); break;
 434                 case 1: *(u8 *)data = val; break;
 435                 }
 436         }
 437
 438         return EMULATE_DO_MMIO;
 439 }
 440
 441 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 442 {
 443         int r;
 444         sigset_t sigsaved;
 445
 446         vcpu_load(vcpu);
 447
 448         if (vcpu->sigset_active)
 449                 sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 450
 451         if (vcpu->mmio_needed) {
 452                 if (!vcpu->mmio_is_write)
 453                         kvmppc_complete_mmio_load(vcpu, run);
 454                 vcpu->mmio_needed = 0;
 455         } else if (vcpu->arch.dcr_needed) {
 456                 if (!vcpu->arch.dcr_is_write)
 457                         kvmppc_complete_dcr_load(vcpu, run);
 458                 vcpu->arch.dcr_needed = 0;
 459         }
 460
 461         kvmppc_check_and_deliver_interrupts(vcpu);
 462
 463         local_irq_disable();
 464         kvm_guest_enter();
 465         r = __kvmppc_vcpu_run(run, vcpu);
 466         kvm_guest_exit();
 467         local_irq_enable();
 468
 469         if (vcpu->sigset_active)
 470                 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
 471
 472         vcpu_put(vcpu);
 473
 474         return r;
 475 }
 476
 477 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq)
 478 {
 479         kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_EXTERNAL);
 480
 481         if (waitqueue_active(&vcpu->wq)) {
 482                 wake_up_interruptible(&vcpu->wq);
 483                 vcpu->stat.halt_wakeup++;
 484         }
 485
 486         return 0;
 487 }
 488
 489 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 490                                     struct kvm_mp_state *mp_state)
 491 {
 492         return -EINVAL;
 493 }
 494
 495 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 496                                     struct kvm_mp_state *mp_state)
 497 {
 498         return -EINVAL;
 499 }
 500
 501 long kvm_arch_vcpu_ioctl(struct file *filp,
 502                          unsigned int ioctl, unsigned long arg)
 503 {
 504         struct kvm_vcpu *vcpu = filp->private_data;
 505         void __user *argp = (void __user *)arg;
 506         long r;
 507
 508         switch (ioctl) {
 509         case KVM_INTERRUPT: {
 510                 struct kvm_interrupt irq;
 511                 r = -EFAULT;
 512                 if (copy_from_user(&irq, argp, sizeof(irq)))
 513                         goto out;
 514                 r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
 515                 break;
 516         }
 517         default:
 518                 r = -EINVAL;
 519         }
 520
 521 out:
 522         return r;
 523 }
 524
 525 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 526 {
 527         return -ENOTSUPP;
 528 }
 529
 530 long kvm_arch_vm_ioctl(struct file *filp,
 531                        unsigned int ioctl, unsigned long arg)
 532 {
 533         long r;
 534
 535         switch (ioctl) {
 536         default:
 537                 r = -EINVAL;
 538         }
 539
 540         return r;
 541 }
 542
 543 int kvm_arch_init(void *opaque)
 544 {
 545         return 0;
 546 }
 547
 548 void kvm_arch_exit(void)
 549 {
 550 }