arch/x86/xen/enlighten.c

   1 /*
   2  * Core of Xen paravirt_ops implementation.
   3  *
   4  * This file contains the xen_paravirt_ops structure itself, and the
   5  * implementations for:
   6  * - privileged instructions
   7  * - interrupt flags
   8  * - segment operations
   9  * - booting and setup
  10  *
  11  * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
  12  */
  13
  14 #include <linux/cpu.h>
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/smp.h>
  18 #include <linux/preempt.h>
  19 #include <linux/hardirq.h>
  20 #include <linux/percpu.h>
  21 #include <linux/delay.h>
  22 #include <linux/start_kernel.h>
  23 #include <linux/sched.h>
  24 #include <linux/kprobes.h>
  25 #include <linux/bootmem.h>
  26 #include <linux/module.h>
  27 #include <linux/mm.h>
  28 #include <linux/page-flags.h>
  29 #include <linux/highmem.h>
  30 #include <linux/console.h>
  31 #include <linux/pci.h>
  32 #include <linux/gfp.h>
  33
  34 #include <xen/xen.h>
  35 #include <xen/interface/xen.h>
  36 #include <xen/interface/version.h>
  37 #include <xen/interface/physdev.h>
  38 #include <xen/interface/vcpu.h>
  39 #include <xen/interface/memory.h>
  40 #include <xen/features.h>
  41 #include <xen/page.h>
  42 #include <xen/hvm.h>
  43 #include <xen/hvc-console.h>
  44
  45 #include <asm/paravirt.h>
  46 #include <asm/apic.h>
  47 #include <asm/page.h>
  48 #include <asm/xen/hypercall.h>
  49 #include <asm/xen/hypervisor.h>
  50 #include <asm/fixmap.h>
  51 #include <asm/processor.h>
  52 #include <asm/proto.h>
  53 #include <asm/msr-index.h>
  54 #include <asm/traps.h>
  55 #include <asm/setup.h>
  56 #include <asm/desc.h>
  57 #include <asm/pgalloc.h>
  58 #include <asm/pgtable.h>
  59 #include <asm/tlbflush.h>
  60 #include <asm/reboot.h>
  61 #include <asm/setup.h>
  62 #include <asm/stackprotector.h>
  63 #include <asm/hypervisor.h>
  64
  65 #include "xen-ops.h"
  66 #include "mmu.h"
  67 #include "multicalls.h"
  68
  69 EXPORT_SYMBOL_GPL(hypercall_page);
  70
  71 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
  72 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
  73
  74 enum xen_domain_type xen_domain_type = XEN_NATIVE;
  75 EXPORT_SYMBOL_GPL(xen_domain_type);
  76
  77 struct start_info *xen_start_info;
  78 EXPORT_SYMBOL_GPL(xen_start_info);
  79
  80 struct shared_info xen_dummy_shared_info;
  81
  82 void *xen_initial_gdt;
  83
  84 RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
  85 __read_mostly int xen_have_vector_callback;
  86 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
  87
  88 /*
  89  * Point at some empty memory to start with. We map the real shared_info
  90  * page as soon as fixmap is up and running.
  91  */
  92 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
  93
  94 /*
  95  * Flag to determine whether vcpu info placement is available on all
  96  * VCPUs.  We assume it is to start with, and then set it to zero on
  97  * the first failure.  This is because it can succeed on some VCPUs
  98  * and not others, since it can involve hypervisor memory allocation,
  99  * or because the guest failed to guarantee all the appropriate
 100  * constraints on all VCPUs (ie buffer can't cross a page boundary).
 101  *
 102  * Note that any particular CPU may be using a placed vcpu structure,
 103  * but we can only optimise if the all are.
 104  *
 105  * 0: not available, 1: available
 106  */
 107 static int have_vcpu_info_placement = 1;
 108
 109 static void clamp_max_cpus(void)
 110 {
 111 #ifdef CONFIG_SMP
 112         if (setup_max_cpus > MAX_VIRT_CPUS)
 113                 setup_max_cpus = MAX_VIRT_CPUS;
 114 #endif
 115 }
 116
 117 static void xen_vcpu_setup(int cpu)
 118 {
 119         struct vcpu_register_vcpu_info info;
 120         int err;
 121         struct vcpu_info *vcpup;
 122
 123         BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
 124
 125         if (cpu < MAX_VIRT_CPUS)
 126                 per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
 127
 128         if (!have_vcpu_info_placement) {
 129                 if (cpu >= MAX_VIRT_CPUS)
 130                         clamp_max_cpus();
 131                 return;
 132         }
 133
 134         vcpup = &per_cpu(xen_vcpu_info, cpu);
 135         info.mfn = arbitrary_virt_to_mfn(vcpup);
 136         info.offset = offset_in_page(vcpup);
 137
 138         printk(KERN_DEBUG "trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
 139                cpu, vcpup, info.mfn, info.offset);
 140
 141         /* Check to see if the hypervisor will put the vcpu_info
 142            structure where we want it, which allows direct access via
 143            a percpu-variable. */
 144         err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
 145
 146         if (err) {
 147                 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
 148                 have_vcpu_info_placement = 0;
 149                 clamp_max_cpus();
 150         } else {
 151                 /* This cpu is using the registered vcpu info, even if
 152                    later ones fail to. */
 153                 per_cpu(xen_vcpu, cpu) = vcpup;
 154
 155                 printk(KERN_DEBUG "cpu %d using vcpu_info at %p\n",
 156                        cpu, vcpup);
 157         }
 158 }
 159
 160 /*
 161  * On restore, set the vcpu placement up again.
 162  * If it fails, then we're in a bad state, since
 163  * we can't back out from using it...
 164  */
 165 void xen_vcpu_restore(void)
 166 {
 167         int cpu;
 168
 169         for_each_online_cpu(cpu) {
 170                 bool other_cpu = (cpu != smp_processor_id());
 171
 172                 if (other_cpu &&
 173                     HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL))
 174                         BUG();
 175
 176                 xen_setup_runstate_info(cpu);
 177
 178                 if (have_vcpu_info_placement)
 179                         xen_vcpu_setup(cpu);
 180
 181                 if (other_cpu &&
 182                     HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL))
 183                         BUG();
 184         }
 185 }
 186
 187 static void __init xen_banner(void)
 188 {
 189         unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
 190         struct xen_extraversion extra;
 191         HYPERVISOR_xen_version(XENVER_extraversion, &extra);
 192
 193         printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
 194                pv_info.name);
 195         printk(KERN_INFO "Xen version: %d.%d%s%s\n",
 196                version >> 16, version & 0xffff, extra.extraversion,
 197                xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
 198 }
 199
 200 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
 201 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
 202
 203 static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 204                       unsigned int *cx, unsigned int *dx)
 205 {
 206         unsigned maskebx = ~0;
 207         unsigned maskecx = ~0;
 208         unsigned maskedx = ~0;
 209
 210         /*
 211          * Mask out inconvenient features, to try and disable as many
 212          * unsupported kernel subsystems as possible.
 213          */
 214         switch (*ax) {
 215         case 1:
 216                 maskecx = cpuid_leaf1_ecx_mask;
 217                 maskedx = cpuid_leaf1_edx_mask;
 218                 break;
 219
 220         case 0xb:
 221                 /* Suppress extended topology stuff */
 222                 maskebx = 0;
 223                 break;
 224         }
 225
 226         asm(XEN_EMULATE_PREFIX "cpuid"
 227                 : "=a" (*ax),
 228                   "=b" (*bx),
 229                   "=c" (*cx),
 230                   "=d" (*dx)
 231                 : "0" (*ax), "2" (*cx));
 232
 233         *bx &= maskebx;
 234         *cx &= maskecx;
 235         *dx &= maskedx;
 236 }
 237
 238 static __init void xen_init_cpuid_mask(void)
 239 {
 240         unsigned int ax, bx, cx, dx;
 241
 242         cpuid_leaf1_edx_mask =
 243                 ~((1 << X86_FEATURE_MCE)  |  /* disable MCE */
 244                   (1 << X86_FEATURE_MCA)  |  /* disable MCA */
 245                   (1 << X86_FEATURE_ACC));   /* thermal monitoring */
 246
 247         if (!xen_initial_domain())
 248                 cpuid_leaf1_edx_mask &=
 249                         ~((1 << X86_FEATURE_APIC) |  /* disable local APIC */
 250                           (1 << X86_FEATURE_ACPI));  /* disable ACPI */
 251
 252         ax = 1;
 253         cx = 0;
 254         xen_cpuid(&ax, &bx, &cx, &dx);
 255
 256         /* cpuid claims we support xsave; try enabling it to see what happens */
 257         if (cx & (1 << (X86_FEATURE_XSAVE % 32))) {
 258                 unsigned long cr4;
 259
 260                 set_in_cr4(X86_CR4_OSXSAVE);
 261
 262                 cr4 = read_cr4();
 263
 264                 if ((cr4 & X86_CR4_OSXSAVE) == 0)
 265                         cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32));
 266
 267                 clear_in_cr4(X86_CR4_OSXSAVE);
 268         }
 269 }
 270
 271 static void xen_set_debugreg(int reg, unsigned long val)
 272 {
 273         HYPERVISOR_set_debugreg(reg, val);
 274 }
 275
 276 static unsigned long xen_get_debugreg(int reg)
 277 {
 278         return HYPERVISOR_get_debugreg(reg);
 279 }
 280
 281 static void xen_end_context_switch(struct task_struct *next)
 282 {
 283         xen_mc_flush();
 284         paravirt_end_context_switch(next);
 285 }
 286
 287 static unsigned long xen_store_tr(void)
 288 {
 289         return 0;
 290 }
 291
 292 /*
 293  * Set the page permissions for a particular virtual address.  If the
 294  * address is a vmalloc mapping (or other non-linear mapping), then
 295  * find the linear mapping of the page and also set its protections to
 296  * match.
 297  */
 298 static void set_aliased_prot(void *v, pgprot_t prot)
 299 {
 300         int level;
 301         pte_t *ptep;
 302         pte_t pte;
 303         unsigned long pfn;
 304         struct page *page;
 305
 306         ptep = lookup_address((unsigned long)v, &level);
 307         BUG_ON(ptep == NULL);
 308
 309         pfn = pte_pfn(*ptep);
 310         page = pfn_to_page(pfn);
 311
 312         pte = pfn_pte(pfn, prot);
 313
 314         if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
 315                 BUG();
 316
 317         if (!PageHighMem(page)) {
 318                 void *av = __va(PFN_PHYS(pfn));
 319
 320                 if (av != v)
 321                         if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
 322                                 BUG();
 323         } else
 324                 kmap_flush_unused();
 325 }
 326
 327 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
 328 {
 329         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
 330         int i;
 331
 332         for(i = 0; i < entries; i += entries_per_page)
 333                 set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
 334 }
 335
 336 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
 337 {
 338         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
 339         int i;
 340
 341         for(i = 0; i < entries; i += entries_per_page)
 342                 set_aliased_prot(ldt + i, PAGE_KERNEL);
 343 }
 344
 345 static void xen_set_ldt(const void *addr, unsigned entries)
 346 {
 347         struct mmuext_op *op;
 348         struct multicall_space mcs = xen_mc_entry(sizeof(*op));
 349
 350         op = mcs.args;
 351         op->cmd = MMUEXT_SET_LDT;
 352         op->arg1.linear_addr = (unsigned long)addr;
 353         op->arg2.nr_ents = entries;
 354
 355         MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
 356
 357         xen_mc_issue(PARAVIRT_LAZY_CPU);
 358 }
 359
 360 static void xen_load_gdt(const struct desc_ptr *dtr)
 361 {
 362         unsigned long va = dtr->address;
 363         unsigned int size = dtr->size + 1;
 364         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 365         unsigned long frames[pages];
 366         int f;
 367
 368         /*
 369          * A GDT can be up to 64k in size, which corresponds to 8192
 370          * 8-byte entries, or 16 4k pages..
 371          */
 372
 373         BUG_ON(size > 65536);
 374         BUG_ON(va & ~PAGE_MASK);
 375
 376         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 377                 int level;
 378                 pte_t *ptep;
 379                 unsigned long pfn, mfn;
 380                 void *virt;
 381
 382                 /*
 383                  * The GDT is per-cpu and is in the percpu data area.
 384                  * That can be virtually mapped, so we need to do a
 385                  * page-walk to get the underlying MFN for the
 386                  * hypercall.  The page can also be in the kernel's
 387                  * linear range, so we need to RO that mapping too.
 388                  */
 389                 ptep = lookup_address(va, &level);
 390                 BUG_ON(ptep == NULL);
 391
 392                 pfn = pte_pfn(*ptep);
 393                 mfn = pfn_to_mfn(pfn);
 394                 virt = __va(PFN_PHYS(pfn));
 395
 396                 frames[f] = mfn;
 397
 398                 make_lowmem_page_readonly((void *)va);
 399                 make_lowmem_page_readonly(virt);
 400         }
 401
 402         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
 403                 BUG();
 404 }
 405
 406 /*
 407  * load_gdt for early boot, when the gdt is only mapped once
 408  */
 409 static __init void xen_load_gdt_boot(const struct desc_ptr *dtr)
 410 {
 411         unsigned long va = dtr->address;
 412         unsigned int size = dtr->size + 1;
 413         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 414         unsigned long frames[pages];
 415         int f;
 416
 417         /*
 418          * A GDT can be up to 64k in size, which corresponds to 8192
 419          * 8-byte entries, or 16 4k pages..
 420          */
 421
 422         BUG_ON(size > 65536);
 423         BUG_ON(va & ~PAGE_MASK);
 424
 425         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 426                 pte_t pte;
 427                 unsigned long pfn, mfn;
 428
 429                 pfn = virt_to_pfn(va);
 430                 mfn = pfn_to_mfn(pfn);
 431
 432                 pte = pfn_pte(pfn, PAGE_KERNEL_RO);
 433
 434                 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
 435                         BUG();
 436
 437                 frames[f] = mfn;
 438         }
 439
 440         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
 441                 BUG();
 442 }
 443
 444 static void load_TLS_descriptor(struct thread_struct *t,
 445                                 unsigned int cpu, unsigned int i)
 446 {
 447         struct desc_struct *gdt = get_cpu_gdt_table(cpu);
 448         xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
 449         struct multicall_space mc = __xen_mc_entry(0);
 450
 451         MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
 452 }
 453
 454 static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 455 {
 456         /*
 457          * XXX sleazy hack: If we're being called in a lazy-cpu zone
 458          * and lazy gs handling is enabled, it means we're in a
 459          * context switch, and %gs has just been saved.  This means we
 460          * can zero it out to prevent faults on exit from the
 461          * hypervisor if the next process has no %gs.  Either way, it
 462          * has been saved, and the new value will get loaded properly.
 463          * This will go away as soon as Xen has been modified to not
 464          * save/restore %gs for normal hypercalls.
 465          *
 466          * On x86_64, this hack is not used for %gs, because gs points
 467          * to KERNEL_GS_BASE (and uses it for PDA references), so we
 468          * must not zero %gs on x86_64
 469          *
 470          * For x86_64, we need to zero %fs, otherwise we may get an
 471          * exception between the new %fs descriptor being loaded and
 472          * %fs being effectively cleared at __switch_to().
 473          */
 474         if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
 475 #ifdef CONFIG_X86_32
 476                 lazy_load_gs(0);
 477 #else
 478                 loadsegment(fs, 0);
 479 #endif
 480         }
 481
 482         xen_mc_batch();
 483
 484         load_TLS_descriptor(t, cpu, 0);
 485         load_TLS_descriptor(t, cpu, 1);
 486         load_TLS_descriptor(t, cpu, 2);
 487
 488         xen_mc_issue(PARAVIRT_LAZY_CPU);
 489 }
 490
 491 #ifdef CONFIG_X86_64
 492 static void xen_load_gs_index(unsigned int idx)
 493 {
 494         if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
 495                 BUG();
 496 }
 497 #endif
 498
 499 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
 500                                 const void *ptr)
 501 {
 502         xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
 503         u64 entry = *(u64 *)ptr;
 504
 505         preempt_disable();
 506
 507         xen_mc_flush();
 508         if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
 509                 BUG();
 510
 511         preempt_enable();
 512 }
 513
 514 static int cvt_gate_to_trap(int vector, const gate_desc *val,
 515                             struct trap_info *info)
 516 {
 517         unsigned long addr;
 518
 519         if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
 520                 return 0;
 521
 522         info->vector = vector;
 523
 524         addr = gate_offset(*val);
 525 #ifdef CONFIG_X86_64
 526         /*
 527          * Look for known traps using IST, and substitute them
 528          * appropriately.  The debugger ones are the only ones we care
 529          * about.  Xen will handle faults like double_fault and
 530          * machine_check, so we should never see them.  Warn if
 531          * there's an unexpected IST-using fault handler.
 532          */
 533         if (addr == (unsigned long)debug)
 534                 addr = (unsigned long)xen_debug;
 535         else if (addr == (unsigned long)int3)
 536                 addr = (unsigned long)xen_int3;
 537         else if (addr == (unsigned long)stack_segment)
 538                 addr = (unsigned long)xen_stack_segment;
 539         else if (addr == (unsigned long)double_fault ||
 540                  addr == (unsigned long)nmi) {
 541                 /* Don't need to handle these */
 542                 return 0;
 543 #ifdef CONFIG_X86_MCE
 544         } else if (addr == (unsigned long)machine_check) {
 545                 return 0;
 546 #endif
 547         } else {
 548                 /* Some other trap using IST? */
 549                 if (WARN_ON(val->ist != 0))
 550                         return 0;
 551         }
 552 #endif  /* CONFIG_X86_64 */
 553         info->address = addr;
 554
 555         info->cs = gate_segment(*val);
 556         info->flags = val->dpl;
 557         /* interrupt gates clear IF */
 558         if (val->type == GATE_INTERRUPT)
 559                 info->flags |= 1 << 2;
 560
 561         return 1;
 562 }
 563
 564 /* Locations of each CPU's IDT */
 565 static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
 566
 567 /* Set an IDT entry.  If the entry is part of the current IDT, then
 568    also update Xen. */
 569 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
 570 {
 571         unsigned long p = (unsigned long)&dt[entrynum];
 572         unsigned long start, end;
 573
 574         preempt_disable();
 575
 576         start = __get_cpu_var(idt_desc).address;
 577         end = start + __get_cpu_var(idt_desc).size + 1;
 578
 579         xen_mc_flush();
 580
 581         native_write_idt_entry(dt, entrynum, g);
 582
 583         if (p >= start && (p + 8) <= end) {
 584                 struct trap_info info[2];
 585
 586                 info[1].address = 0;
 587
 588                 if (cvt_gate_to_trap(entrynum, g, &info[0]))
 589                         if (HYPERVISOR_set_trap_table(info))
 590                                 BUG();
 591         }
 592
 593         preempt_enable();
 594 }
 595
 596 static void xen_convert_trap_info(const struct desc_ptr *desc,
 597                                   struct trap_info *traps)
 598 {
 599         unsigned in, out, count;
 600
 601         count = (desc->size+1) / sizeof(gate_desc);
 602         BUG_ON(count > 256);
 603
 604         for (in = out = 0; in < count; in++) {
 605                 gate_desc *entry = (gate_desc*)(desc->address) + in;
 606
 607                 if (cvt_gate_to_trap(in, entry, &traps[out]))
 608                         out++;
 609         }
 610         traps[out].address = 0;
 611 }
 612
 613 void xen_copy_trap_info(struct trap_info *traps)
 614 {
 615         const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
 616
 617         xen_convert_trap_info(desc, traps);
 618 }
 619
 620 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
 621    hold a spinlock to protect the static traps[] array (static because
 622    it avoids allocation, and saves stack space). */
 623 static void xen_load_idt(const struct desc_ptr *desc)
 624 {
 625         static DEFINE_SPINLOCK(lock);
 626         static struct trap_info traps[257];
 627
 628         spin_lock(&lock);
 629
 630         __get_cpu_var(idt_desc) = *desc;
 631
 632         xen_convert_trap_info(desc, traps);
 633
 634         xen_mc_flush();
 635         if (HYPERVISOR_set_trap_table(traps))
 636                 BUG();
 637
 638         spin_unlock(&lock);
 639 }
 640
 641 /* Write a GDT descriptor entry.  Ignore LDT descriptors, since
 642    they're handled differently. */
 643 static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
 644                                 const void *desc, int type)
 645 {
 646         preempt_disable();
 647
 648         switch (type) {
 649         case DESC_LDT:
 650         case DESC_TSS:
 651                 /* ignore */
 652                 break;
 653
 654         default: {
 655                 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
 656
 657                 xen_mc_flush();
 658                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
 659                         BUG();
 660         }
 661
 662         }
 663
 664         preempt_enable();
 665 }
 666
 667 /*
 668  * Version of write_gdt_entry for use at early boot-time needed to
 669  * update an entry as simply as possible.
 670  */
 671 static __init void xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
 672                                             const void *desc, int type)
 673 {
 674         switch (type) {
 675         case DESC_LDT:
 676         case DESC_TSS:
 677                 /* ignore */
 678                 break;
 679
 680         default: {
 681                 xmaddr_t maddr = virt_to_machine(&dt[entry]);
 682
 683                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
 684                         dt[entry] = *(struct desc_struct *)desc;
 685         }
 686
 687         }
 688 }
 689
 690 static void xen_load_sp0(struct tss_struct *tss,
 691                          struct thread_struct *thread)
 692 {
 693         struct multicall_space mcs = xen_mc_entry(0);
 694         MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
 695         xen_mc_issue(PARAVIRT_LAZY_CPU);
 696 }
 697
 698 static void xen_set_iopl_mask(unsigned mask)
 699 {
 700         struct physdev_set_iopl set_iopl;
 701
 702         /* Force the change at ring 0. */
 703         set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
 704         HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 705 }
 706
 707 static void xen_io_delay(void)
 708 {
 709 }
 710
 711 #ifdef CONFIG_X86_LOCAL_APIC
 712 static u32 xen_apic_read(u32 reg)
 713 {
 714         return 0;
 715 }
 716
 717 static void xen_apic_write(u32 reg, u32 val)
 718 {
 719         /* Warn to see if there's any stray references */
 720         WARN_ON(1);
 721 }
 722
 723 static u64 xen_apic_icr_read(void)
 724 {
 725         return 0;
 726 }
 727
 728 static void xen_apic_icr_write(u32 low, u32 id)
 729 {
 730         /* Warn to see if there's any stray references */
 731         WARN_ON(1);
 732 }
 733
 734 static void xen_apic_wait_icr_idle(void)
 735 {
 736         return;
 737 }
 738
 739 static u32 xen_safe_apic_wait_icr_idle(void)
 740 {
 741         return 0;
 742 }
 743
 744 static void set_xen_basic_apic_ops(void)
 745 {
 746         apic->read = xen_apic_read;
 747         apic->write = xen_apic_write;
 748         apic->icr_read = xen_apic_icr_read;
 749         apic->icr_write = xen_apic_icr_write;
 750         apic->wait_icr_idle = xen_apic_wait_icr_idle;
 751         apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
 752 }
 753
 754 #endif
 755
 756 static void xen_clts(void)
 757 {
 758         struct multicall_space mcs;
 759
 760         mcs = xen_mc_entry(0);
 761
 762         MULTI_fpu_taskswitch(mcs.mc, 0);
 763
 764         xen_mc_issue(PARAVIRT_LAZY_CPU);
 765 }
 766
 767 static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
 768
 769 static unsigned long xen_read_cr0(void)
 770 {
 771         unsigned long cr0 = percpu_read(xen_cr0_value);
 772
 773         if (unlikely(cr0 == 0)) {
 774                 cr0 = native_read_cr0();
 775                 percpu_write(xen_cr0_value, cr0);
 776         }
 777
 778         return cr0;
 779 }
 780
 781 static void xen_write_cr0(unsigned long cr0)
 782 {
 783         struct multicall_space mcs;
 784
 785         percpu_write(xen_cr0_value, cr0);
 786
 787         /* Only pay attention to cr0.TS; everything else is
 788            ignored. */
 789         mcs = xen_mc_entry(0);
 790
 791         MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
 792
 793         xen_mc_issue(PARAVIRT_LAZY_CPU);
 794 }
 795
 796 static void xen_write_cr4(unsigned long cr4)
 797 {
 798         cr4 &= ~X86_CR4_PGE;
 799         cr4 &= ~X86_CR4_PSE;
 800
 801         native_write_cr4(cr4);
 802 }
 803
 804 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
 805 {
 806         int ret;
 807
 808         ret = 0;
 809
 810         switch (msr) {
 811 #ifdef CONFIG_X86_64
 812                 unsigned which;
 813                 u64 base;
 814
 815         case MSR_FS_BASE:               which = SEGBASE_FS; goto set;
 816         case MSR_KERNEL_GS_BASE:        which = SEGBASE_GS_USER; goto set;
 817         case MSR_GS_BASE:               which = SEGBASE_GS_KERNEL; goto set;
 818
 819         set:
 820                 base = ((u64)high << 32) | low;
 821                 if (HYPERVISOR_set_segment_base(which, base) != 0)
 822                         ret = -EIO;
 823                 break;
 824 #endif
 825
 826         case MSR_STAR:
 827         case MSR_CSTAR:
 828         case MSR_LSTAR:
 829         case MSR_SYSCALL_MASK:
 830         case MSR_IA32_SYSENTER_CS:
 831         case MSR_IA32_SYSENTER_ESP:
 832         case MSR_IA32_SYSENTER_EIP:
 833                 /* Fast syscall setup is all done in hypercalls, so
 834                    these are all ignored.  Stub them out here to stop
 835                    Xen console noise. */
 836                 break;
 837
 838         default:
 839                 ret = native_write_msr_safe(msr, low, high);
 840         }
 841
 842         return ret;
 843 }
 844
 845 void xen_setup_shared_info(void)
 846 {
 847         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 848                 set_fixmap(FIX_PARAVIRT_BOOTMAP,
 849                            xen_start_info->shared_info);
 850
 851                 HYPERVISOR_shared_info =
 852                         (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
 853         } else
 854                 HYPERVISOR_shared_info =
 855                         (struct shared_info *)__va(xen_start_info->shared_info);
 856
 857 #ifndef CONFIG_SMP
 858         /* In UP this is as good a place as any to set up shared info */
 859         xen_setup_vcpu_info_placement();
 860 #endif
 861
 862         xen_setup_mfn_list_list();
 863 }
 864
 865 /* This is called once we have the cpu_possible_map */
 866 void xen_setup_vcpu_info_placement(void)
 867 {
 868         int cpu;
 869
 870         for_each_possible_cpu(cpu)
 871                 xen_vcpu_setup(cpu);
 872
 873         /* xen_vcpu_setup managed to place the vcpu_info within the
 874            percpu area for all cpus, so make use of it */
 875         if (have_vcpu_info_placement) {
 876                 printk(KERN_INFO "Xen: using vcpu_info placement\n");
 877
 878                 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
 879                 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
 880                 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
 881                 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
 882                 pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
 883         }
 884 }
 885
 886 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
 887                           unsigned long addr, unsigned len)
 888 {
 889         char *start, *end, *reloc;
 890         unsigned ret;
 891
 892         start = end = reloc = NULL;
 893
 894 #define SITE(op, x)                                                     \
 895         case PARAVIRT_PATCH(op.x):                                      \
 896         if (have_vcpu_info_placement) {                                 \
 897                 start = (char *)xen_##x##_direct;                       \
 898                 end = xen_##x##_direct_end;                             \
 899                 reloc = xen_##x##_direct_reloc;                         \
 900         }                                                               \
 901         goto patch_site
 902
 903         switch (type) {
 904                 SITE(pv_irq_ops, irq_enable);
 905                 SITE(pv_irq_ops, irq_disable);
 906                 SITE(pv_irq_ops, save_fl);
 907                 SITE(pv_irq_ops, restore_fl);
 908 #undef SITE
 909
 910         patch_site:
 911                 if (start == NULL || (end-start) > len)
 912                         goto default_patch;
 913
 914                 ret = paravirt_patch_insns(insnbuf, len, start, end);
 915
 916                 /* Note: because reloc is assigned from something that
 917                    appears to be an array, gcc assumes it's non-null,
 918                    but doesn't know its relationship with start and
 919                    end. */
 920                 if (reloc > start && reloc < end) {
 921                         int reloc_off = reloc - start;
 922                         long *relocp = (long *)(insnbuf + reloc_off);
 923                         long delta = start - (char *)addr;
 924
 925                         *relocp += delta;
 926                 }
 927                 break;
 928
 929         default_patch:
 930         default:
 931                 ret = paravirt_patch_default(type, clobbers, insnbuf,
 932                                              addr, len);
 933                 break;
 934         }
 935
 936         return ret;
 937 }
 938
 939 static const struct pv_info xen_info __initdata = {
 940         .paravirt_enabled = 1,
 941         .shared_kernel_pmd = 0,
 942
 943         .name = "Xen",
 944 };
 945
 946 static const struct pv_init_ops xen_init_ops __initdata = {
 947         .patch = xen_patch,
 948 };
 949
 950 static const struct pv_cpu_ops xen_cpu_ops __initdata = {
 951         .cpuid = xen_cpuid,
 952
 953         .set_debugreg = xen_set_debugreg,
 954         .get_debugreg = xen_get_debugreg,
 955
 956         .clts = xen_clts,
 957
 958         .read_cr0 = xen_read_cr0,
 959         .write_cr0 = xen_write_cr0,
 960
 961         .read_cr4 = native_read_cr4,
 962         .read_cr4_safe = native_read_cr4_safe,
 963         .write_cr4 = xen_write_cr4,
 964
 965         .wbinvd = native_wbinvd,
 966
 967         .read_msr = native_read_msr_safe,
 968         .write_msr = xen_write_msr_safe,
 969         .read_tsc = native_read_tsc,
 970         .read_pmc = native_read_pmc,
 971
 972         .iret = xen_iret,
 973         .irq_enable_sysexit = xen_sysexit,
 974 #ifdef CONFIG_X86_64
 975         .usergs_sysret32 = xen_sysret32,
 976         .usergs_sysret64 = xen_sysret64,
 977 #endif
 978
 979         .load_tr_desc = paravirt_nop,
 980         .set_ldt = xen_set_ldt,
 981         .load_gdt = xen_load_gdt,
 982         .load_idt = xen_load_idt,
 983         .load_tls = xen_load_tls,
 984 #ifdef CONFIG_X86_64
 985         .load_gs_index = xen_load_gs_index,
 986 #endif
 987
 988         .alloc_ldt = xen_alloc_ldt,
 989         .free_ldt = xen_free_ldt,
 990
 991         .store_gdt = native_store_gdt,
 992         .store_idt = native_store_idt,
 993         .store_tr = xen_store_tr,
 994
 995         .write_ldt_entry = xen_write_ldt_entry,
 996         .write_gdt_entry = xen_write_gdt_entry,
 997         .write_idt_entry = xen_write_idt_entry,
 998         .load_sp0 = xen_load_sp0,
 999
1000         .set_iopl_mask = xen_set_iopl_mask,
1001         .io_delay = xen_io_delay,
1002
1003         /* Xen takes care of %gs when switching to usermode for us */
1004         .swapgs = paravirt_nop,
1005
1006         .start_context_switch = paravirt_start_context_switch,
1007         .end_context_switch = xen_end_context_switch,
1008 };
1009
1010 static const struct pv_apic_ops xen_apic_ops __initdata = {
1011 #ifdef CONFIG_X86_LOCAL_APIC
1012         .startup_ipi_hook = paravirt_nop,
1013 #endif
1014 };
1015
1016 static void xen_reboot(int reason)
1017 {
1018         struct sched_shutdown r = { .reason = reason };
1019
1020 #ifdef CONFIG_SMP
1021         smp_send_stop();
1022 #endif
1023
1024         if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
1025                 BUG();
1026 }
1027
1028 static void xen_restart(char *msg)
1029 {
1030         xen_reboot(SHUTDOWN_reboot);
1031 }
1032
1033 static void xen_emergency_restart(void)
1034 {
1035         xen_reboot(SHUTDOWN_reboot);
1036 }
1037
1038 static void xen_machine_halt(void)
1039 {
1040         xen_reboot(SHUTDOWN_poweroff);
1041 }
1042
1043 static void xen_crash_shutdown(struct pt_regs *regs)
1044 {
1045         xen_reboot(SHUTDOWN_crash);
1046 }
1047
1048 static int
1049 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
1050 {
1051         xen_reboot(SHUTDOWN_crash);
1052         return NOTIFY_DONE;
1053 }
1054
1055 static struct notifier_block xen_panic_block = {
1056         .notifier_call= xen_panic_event,
1057 };
1058
1059 int xen_panic_handler_init(void)
1060 {
1061         atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
1062         return 0;
1063 }
1064
1065 static const struct machine_ops __initdata xen_machine_ops = {
1066         .restart = xen_restart,
1067         .halt = xen_machine_halt,
1068         .power_off = xen_machine_halt,
1069         .shutdown = xen_machine_halt,
1070         .crash_shutdown = xen_crash_shutdown,
1071         .emergency_restart = xen_emergency_restart,
1072 };
1073
1074 /*
1075  * Set up the GDT and segment registers for -fstack-protector.  Until
1076  * we do this, we have to be careful not to call any stack-protected
1077  * function, which is most of the kernel.
1078  */
1079 static void __init xen_setup_stackprotector(void)
1080 {
1081         pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot;
1082         pv_cpu_ops.load_gdt = xen_load_gdt_boot;
1083
1084         setup_stack_canary_segment(0);
1085         switch_to_new_gdt(0);
1086
1087         pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry;
1088         pv_cpu_ops.load_gdt = xen_load_gdt;
1089 }
1090
1091 /* First C function to be called on Xen boot */
1092 asmlinkage void __init xen_start_kernel(void)
1093 {
1094         pgd_t *pgd;
1095
1096         if (!xen_start_info)
1097                 return;
1098
1099         xen_domain_type = XEN_PV_DOMAIN;
1100
1101         /* Install Xen paravirt ops */
1102         pv_info = xen_info;
1103         pv_init_ops = xen_init_ops;
1104         pv_cpu_ops = xen_cpu_ops;
1105         pv_apic_ops = xen_apic_ops;
1106
1107         x86_init.resources.memory_setup = xen_memory_setup;
1108         x86_init.oem.arch_setup = xen_arch_setup;
1109         x86_init.oem.banner = xen_banner;
1110
1111         xen_init_time_ops();
1112
1113         /*
1114          * Set up some pagetable state before starting to set any ptes.
1115          */
1116
1117         xen_init_mmu_ops();
1118
1119         /* Prevent unwanted bits from being set in PTEs. */
1120         __supported_pte_mask &= ~_PAGE_GLOBAL;
1121         if (!xen_initial_domain())
1122                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1123
1124         __supported_pte_mask |= _PAGE_IOMAP;
1125
1126         /*
1127          * Prevent page tables from being allocated in highmem, even
1128          * if CONFIG_HIGHPTE is enabled.
1129          */
1130         __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
1131
1132         /* Work out if we support NX */
1133         x86_configure_nx();
1134
1135         xen_setup_features();
1136
1137         /* Get mfn list */
1138         if (!xen_feature(XENFEAT_auto_translated_physmap))
1139                 xen_build_dynamic_phys_to_machine();
1140
1141         /*
1142          * Set up kernel GDT and segment registers, mainly so that
1143          * -fstack-protector code can be executed.
1144          */
1145         xen_setup_stackprotector();
1146
1147         xen_init_irq_ops();
1148         xen_init_cpuid_mask();
1149
1150 #ifdef CONFIG_X86_LOCAL_APIC
1151         /*
1152          * set up the basic apic ops.
1153          */
1154         set_xen_basic_apic_ops();
1155 #endif
1156
1157         if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
1158                 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
1159                 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
1160         }
1161
1162         machine_ops = xen_machine_ops;
1163
1164         /*
1165          * The only reliable way to retain the initial address of the
1166          * percpu gdt_page is to remember it here, so we can go and
1167          * mark it RW later, when the initial percpu area is freed.
1168          */
1169         xen_initial_gdt = &per_cpu(gdt_page, 0);
1170
1171         xen_smp_init();
1172
1173         pgd = (pgd_t *)xen_start_info->pt_base;
1174
1175         if (!xen_initial_domain())
1176                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1177
1178         __supported_pte_mask |= _PAGE_IOMAP;
1179         /* Don't do the full vcpu_info placement stuff until we have a
1180            possible map and a non-dummy shared_info. */
1181         per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
1182
1183         local_irq_disable();
1184         early_boot_irqs_off();
1185
1186         xen_raw_console_write("mapping kernel into physical memory\n");
1187         pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
1188
1189         init_mm.pgd = pgd;
1190
1191         /* keep using Xen gdt for now; no urgent need to change it */
1192
1193 #ifdef CONFIG_X86_32
1194         pv_info.kernel_rpl = 1;
1195         if (xen_feature(XENFEAT_supervisor_mode_kernel))
1196                 pv_info.kernel_rpl = 0;
1197 #else
1198         pv_info.kernel_rpl = 0;
1199 #endif
1200
1201         /* set the limit of our address space */
1202         xen_reserve_top();
1203
1204 #ifdef CONFIG_X86_32
1205         /* set up basic CPUID stuff */
1206         cpu_detect(&new_cpu_data);
1207         new_cpu_data.hard_math = 1;
1208         new_cpu_data.wp_works_ok = 1;
1209         new_cpu_data.x86_capability[0] = cpuid_edx(1);
1210 #endif
1211
1212         /* Poke various useful things into boot_params */
1213         boot_params.hdr.type_of_loader = (9 << 4) | 0;
1214         boot_params.hdr.ramdisk_image = xen_start_info->mod_start
1215                 ? __pa(xen_start_info->mod_start) : 0;
1216         boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
1217         boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
1218
1219         if (!xen_initial_domain()) {
1220                 add_preferred_console("xenboot", 0, NULL);
1221                 add_preferred_console("tty", 0, NULL);
1222                 add_preferred_console("hvc", 0, NULL);
1223         } else {
1224                 /* Make sure ACS will be enabled */
1225                 pci_request_acs();
1226         }
1227
1228
1229         xen_raw_console_write("about to get started...\n");
1230
1231         xen_setup_runstate_info(0);
1232
1233         /* Start the world */
1234 #ifdef CONFIG_X86_32
1235         i386_start_kernel();
1236 #else
1237         x86_64_start_reservations((char *)__pa_symbol(&boot_params));
1238 #endif
1239 }
1240
1241 static uint32_t xen_cpuid_base(void)
1242 {
1243         uint32_t base, eax, ebx, ecx, edx;
1244         char signature[13];
1245
1246         for (base = 0x40000000; base < 0x40010000; base += 0x100) {
1247                 cpuid(base, &eax, &ebx, &ecx, &edx);
1248                 *(uint32_t *)(signature + 0) = ebx;
1249                 *(uint32_t *)(signature + 4) = ecx;
1250                 *(uint32_t *)(signature + 8) = edx;
1251                 signature[12] = 0;
1252
1253                 if (!strcmp("XenVMMXenVMM", signature) && ((eax - base) >= 2))
1254                         return base;
1255         }
1256
1257         return 0;
1258 }
1259
1260 static int init_hvm_pv_info(int *major, int *minor)
1261 {
1262         uint32_t eax, ebx, ecx, edx, pages, msr, base;
1263         u64 pfn;
1264
1265         base = xen_cpuid_base();
1266         cpuid(base + 1, &eax, &ebx, &ecx, &edx);
1267
1268         *major = eax >> 16;
1269         *minor = eax & 0xffff;
1270         printk(KERN_INFO "Xen version %d.%d.\n", *major, *minor);
1271
1272         cpuid(base + 2, &pages, &msr, &ecx, &edx);
1273
1274         pfn = __pa(hypercall_page);
1275         wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
1276
1277         xen_setup_features();
1278
1279         pv_info = xen_info;
1280         pv_info.kernel_rpl = 0;
1281
1282         xen_domain_type = XEN_HVM_DOMAIN;
1283
1284         return 0;
1285 }
1286
1287 void xen_hvm_init_shared_info(void)
1288 {
1289         int cpu;
1290         struct xen_add_to_physmap xatp;
1291         static struct shared_info *shared_info_page = 0;
1292
1293         if (!shared_info_page)
1294                 shared_info_page = (struct shared_info *)
1295                         extend_brk(PAGE_SIZE, PAGE_SIZE);
1296         xatp.domid = DOMID_SELF;
1297         xatp.idx = 0;
1298         xatp.space = XENMAPSPACE_shared_info;
1299         xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
1300         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
1301                 BUG();
1302
1303         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
1304
1305         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1306          * page, we use it in the event channel upcall and in some pvclock
1307          * related functions. We don't need the vcpu_info placement
1308          * optimizations because we don't use any pv_mmu or pv_irq op on
1309          * HVM.
1310          * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1311          * online but xen_hvm_init_shared_info is run at resume time too and
1312          * in that case multiple vcpus might be online. */
1313         for_each_online_cpu(cpu) {
1314                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1315         }
1316 }
1317
1318 #ifdef CONFIG_XEN_PVHVM
1319 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
1320                                     unsigned long action, void *hcpu)
1321 {
1322         int cpu = (long)hcpu;
1323         switch (action) {
1324         case CPU_UP_PREPARE:
1325                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1326                 break;
1327         default:
1328                 break;
1329         }
1330         return NOTIFY_OK;
1331 }
1332
1333 static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier = {
1334         .notifier_call  = xen_hvm_cpu_notify,
1335 };
1336
1337 static void __init xen_hvm_guest_init(void)
1338 {
1339         int r;
1340         int major, minor;
1341
1342         r = init_hvm_pv_info(&major, &minor);
1343         if (r < 0)
1344                 return;
1345
1346         xen_hvm_init_shared_info();
1347
1348         if (xen_feature(XENFEAT_hvm_callback_vector))
1349                 xen_have_vector_callback = 1;
1350         register_cpu_notifier(&xen_hvm_cpu_notifier);
1351         xen_unplug_emulated_devices();
1352         have_vcpu_info_placement = 0;
1353         x86_init.irqs.intr_init = xen_init_IRQ;
1354         xen_hvm_init_time_ops();
1355         xen_hvm_init_mmu_ops();
1356 }
1357
1358 static bool __init xen_hvm_platform(void)
1359 {
1360         if (xen_pv_domain())
1361                 return false;
1362
1363         if (!xen_cpuid_base())
1364                 return false;
1365
1366         return true;
1367 }
1368
1369 const __refconst struct hypervisor_x86 x86_hyper_xen_hvm = {
1370         .name                   = "Xen HVM",
1371         .detect                 = xen_hvm_platform,
1372         .init_platform          = xen_hvm_guest_init,
1373 };
1374 EXPORT_SYMBOL(x86_hyper_xen_hvm);
1375 #endif