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 #include <linux/memblock.h>
  34
  35 #include <xen/xen.h>
  36 #include <xen/interface/xen.h>
  37 #include <xen/interface/version.h>
  38 #include <xen/interface/physdev.h>
  39 #include <xen/interface/vcpu.h>
  40 #include <xen/interface/memory.h>
  41 #include <xen/features.h>
  42 #include <xen/page.h>
  43 #include <xen/hvm.h>
  44 #include <xen/hvc-console.h>
  45
  46 #include <asm/paravirt.h>
  47 #include <asm/apic.h>
  48 #include <asm/page.h>
  49 #include <asm/xen/hypercall.h>
  50 #include <asm/xen/hypervisor.h>
  51 #include <asm/fixmap.h>
  52 #include <asm/processor.h>
  53 #include <asm/proto.h>
  54 #include <asm/msr-index.h>
  55 #include <asm/traps.h>
  56 #include <asm/setup.h>
  57 #include <asm/desc.h>
  58 #include <asm/pgalloc.h>
  59 #include <asm/pgtable.h>
  60 #include <asm/tlbflush.h>
  61 #include <asm/reboot.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         /* Check to see if the hypervisor will put the vcpu_info
 139            structure where we want it, which allows direct access via
 140            a percpu-variable. */
 141         err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
 142
 143         if (err) {
 144                 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
 145                 have_vcpu_info_placement = 0;
 146                 clamp_max_cpus();
 147         } else {
 148                 /* This cpu is using the registered vcpu info, even if
 149                    later ones fail to. */
 150                 per_cpu(xen_vcpu, cpu) = vcpup;
 151         }
 152 }
 153
 154 /*
 155  * On restore, set the vcpu placement up again.
 156  * If it fails, then we're in a bad state, since
 157  * we can't back out from using it...
 158  */
 159 void xen_vcpu_restore(void)
 160 {
 161         int cpu;
 162
 163         for_each_online_cpu(cpu) {
 164                 bool other_cpu = (cpu != smp_processor_id());
 165
 166                 if (other_cpu &&
 167                     HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL))
 168                         BUG();
 169
 170                 xen_setup_runstate_info(cpu);
 171
 172                 if (have_vcpu_info_placement)
 173                         xen_vcpu_setup(cpu);
 174
 175                 if (other_cpu &&
 176                     HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL))
 177                         BUG();
 178         }
 179 }
 180
 181 static void __init xen_banner(void)
 182 {
 183         unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
 184         struct xen_extraversion extra;
 185         HYPERVISOR_xen_version(XENVER_extraversion, &extra);
 186
 187         printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
 188                pv_info.name);
 189         printk(KERN_INFO "Xen version: %d.%d%s%s\n",
 190                version >> 16, version & 0xffff, extra.extraversion,
 191                xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
 192 }
 193
 194 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
 195 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
 196
 197 static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 198                       unsigned int *cx, unsigned int *dx)
 199 {
 200         unsigned maskebx = ~0;
 201         unsigned maskecx = ~0;
 202         unsigned maskedx = ~0;
 203
 204         /*
 205          * Mask out inconvenient features, to try and disable as many
 206          * unsupported kernel subsystems as possible.
 207          */
 208         switch (*ax) {
 209         case 1:
 210                 maskecx = cpuid_leaf1_ecx_mask;
 211                 maskedx = cpuid_leaf1_edx_mask;
 212                 break;
 213
 214         case 0xb:
 215                 /* Suppress extended topology stuff */
 216                 maskebx = 0;
 217                 break;
 218         }
 219
 220         asm(XEN_EMULATE_PREFIX "cpuid"
 221                 : "=a" (*ax),
 222                   "=b" (*bx),
 223                   "=c" (*cx),
 224                   "=d" (*dx)
 225                 : "0" (*ax), "2" (*cx));
 226
 227         *bx &= maskebx;
 228         *cx &= maskecx;
 229         *dx &= maskedx;
 230 }
 231
 232 static __init void xen_init_cpuid_mask(void)
 233 {
 234         unsigned int ax, bx, cx, dx;
 235
 236         cpuid_leaf1_edx_mask =
 237                 ~((1 << X86_FEATURE_MCE)  |  /* disable MCE */
 238                   (1 << X86_FEATURE_MCA)  |  /* disable MCA */
 239                   (1 << X86_FEATURE_ACC));   /* thermal monitoring */
 240
 241         if (!xen_initial_domain())
 242                 cpuid_leaf1_edx_mask &=
 243                         ~((1 << X86_FEATURE_APIC) |  /* disable local APIC */
 244                           (1 << X86_FEATURE_ACPI));  /* disable ACPI */
 245
 246         ax = 1;
 247         cx = 0;
 248         xen_cpuid(&ax, &bx, &cx, &dx);
 249
 250         /* cpuid claims we support xsave; try enabling it to see what happens */
 251         if (cx & (1 << (X86_FEATURE_XSAVE % 32))) {
 252                 unsigned long cr4;
 253
 254                 set_in_cr4(X86_CR4_OSXSAVE);
 255
 256                 cr4 = read_cr4();
 257
 258                 if ((cr4 & X86_CR4_OSXSAVE) == 0)
 259                         cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32));
 260
 261                 clear_in_cr4(X86_CR4_OSXSAVE);
 262         }
 263 }
 264
 265 static void xen_set_debugreg(int reg, unsigned long val)
 266 {
 267         HYPERVISOR_set_debugreg(reg, val);
 268 }
 269
 270 static unsigned long xen_get_debugreg(int reg)
 271 {
 272         return HYPERVISOR_get_debugreg(reg);
 273 }
 274
 275 static void xen_end_context_switch(struct task_struct *next)
 276 {
 277         xen_mc_flush();
 278         paravirt_end_context_switch(next);
 279 }
 280
 281 static unsigned long xen_store_tr(void)
 282 {
 283         return 0;
 284 }
 285
 286 /*
 287  * Set the page permissions for a particular virtual address.  If the
 288  * address is a vmalloc mapping (or other non-linear mapping), then
 289  * find the linear mapping of the page and also set its protections to
 290  * match.
 291  */
 292 static void set_aliased_prot(void *v, pgprot_t prot)
 293 {
 294         int level;
 295         pte_t *ptep;
 296         pte_t pte;
 297         unsigned long pfn;
 298         struct page *page;
 299
 300         ptep = lookup_address((unsigned long)v, &level);
 301         BUG_ON(ptep == NULL);
 302
 303         pfn = pte_pfn(*ptep);
 304         page = pfn_to_page(pfn);
 305
 306         pte = pfn_pte(pfn, prot);
 307
 308         if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
 309                 BUG();
 310
 311         if (!PageHighMem(page)) {
 312                 void *av = __va(PFN_PHYS(pfn));
 313
 314                 if (av != v)
 315                         if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
 316                                 BUG();
 317         } else
 318                 kmap_flush_unused();
 319 }
 320
 321 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
 322 {
 323         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
 324         int i;
 325
 326         for(i = 0; i < entries; i += entries_per_page)
 327                 set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
 328 }
 329
 330 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
 331 {
 332         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
 333         int i;
 334
 335         for(i = 0; i < entries; i += entries_per_page)
 336                 set_aliased_prot(ldt + i, PAGE_KERNEL);
 337 }
 338
 339 static void xen_set_ldt(const void *addr, unsigned entries)
 340 {
 341         struct mmuext_op *op;
 342         struct multicall_space mcs = xen_mc_entry(sizeof(*op));
 343
 344         op = mcs.args;
 345         op->cmd = MMUEXT_SET_LDT;
 346         op->arg1.linear_addr = (unsigned long)addr;
 347         op->arg2.nr_ents = entries;
 348
 349         MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
 350
 351         xen_mc_issue(PARAVIRT_LAZY_CPU);
 352 }
 353
 354 static void xen_load_gdt(const struct desc_ptr *dtr)
 355 {
 356         unsigned long va = dtr->address;
 357         unsigned int size = dtr->size + 1;
 358         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 359         unsigned long frames[pages];
 360         int f;
 361
 362         /*
 363          * A GDT can be up to 64k in size, which corresponds to 8192
 364          * 8-byte entries, or 16 4k pages..
 365          */
 366
 367         BUG_ON(size > 65536);
 368         BUG_ON(va & ~PAGE_MASK);
 369
 370         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 371                 int level;
 372                 pte_t *ptep;
 373                 unsigned long pfn, mfn;
 374                 void *virt;
 375
 376                 /*
 377                  * The GDT is per-cpu and is in the percpu data area.
 378                  * That can be virtually mapped, so we need to do a
 379                  * page-walk to get the underlying MFN for the
 380                  * hypercall.  The page can also be in the kernel's
 381                  * linear range, so we need to RO that mapping too.
 382                  */
 383                 ptep = lookup_address(va, &level);
 384                 BUG_ON(ptep == NULL);
 385
 386                 pfn = pte_pfn(*ptep);
 387                 mfn = pfn_to_mfn(pfn);
 388                 virt = __va(PFN_PHYS(pfn));
 389
 390                 frames[f] = mfn;
 391
 392                 make_lowmem_page_readonly((void *)va);
 393                 make_lowmem_page_readonly(virt);
 394         }
 395
 396         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
 397                 BUG();
 398 }
 399
 400 /*
 401  * load_gdt for early boot, when the gdt is only mapped once
 402  */
 403 static __init void xen_load_gdt_boot(const struct desc_ptr *dtr)
 404 {
 405         unsigned long va = dtr->address;
 406         unsigned int size = dtr->size + 1;
 407         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 408         unsigned long frames[pages];
 409         int f;
 410
 411         /*
 412          * A GDT can be up to 64k in size, which corresponds to 8192
 413          * 8-byte entries, or 16 4k pages..
 414          */
 415
 416         BUG_ON(size > 65536);
 417         BUG_ON(va & ~PAGE_MASK);
 418
 419         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 420                 pte_t pte;
 421                 unsigned long pfn, mfn;
 422
 423                 pfn = virt_to_pfn(va);
 424                 mfn = pfn_to_mfn(pfn);
 425
 426                 pte = pfn_pte(pfn, PAGE_KERNEL_RO);
 427
 428                 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
 429                         BUG();
 430
 431                 frames[f] = mfn;
 432         }
 433
 434         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
 435                 BUG();
 436 }
 437
 438 static void load_TLS_descriptor(struct thread_struct *t,
 439                                 unsigned int cpu, unsigned int i)
 440 {
 441         struct desc_struct *gdt = get_cpu_gdt_table(cpu);
 442         xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
 443         struct multicall_space mc = __xen_mc_entry(0);
 444
 445         MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
 446 }
 447
 448 static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 449 {
 450         /*
 451          * XXX sleazy hack: If we're being called in a lazy-cpu zone
 452          * and lazy gs handling is enabled, it means we're in a
 453          * context switch, and %gs has just been saved.  This means we
 454          * can zero it out to prevent faults on exit from the
 455          * hypervisor if the next process has no %gs.  Either way, it
 456          * has been saved, and the new value will get loaded properly.
 457          * This will go away as soon as Xen has been modified to not
 458          * save/restore %gs for normal hypercalls.
 459          *
 460          * On x86_64, this hack is not used for %gs, because gs points
 461          * to KERNEL_GS_BASE (and uses it for PDA references), so we
 462          * must not zero %gs on x86_64
 463          *
 464          * For x86_64, we need to zero %fs, otherwise we may get an
 465          * exception between the new %fs descriptor being loaded and
 466          * %fs being effectively cleared at __switch_to().
 467          */
 468         if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
 469 #ifdef CONFIG_X86_32
 470                 lazy_load_gs(0);
 471 #else
 472                 loadsegment(fs, 0);
 473 #endif
 474         }
 475
 476         xen_mc_batch();
 477
 478         load_TLS_descriptor(t, cpu, 0);
 479         load_TLS_descriptor(t, cpu, 1);
 480         load_TLS_descriptor(t, cpu, 2);
 481
 482         xen_mc_issue(PARAVIRT_LAZY_CPU);
 483 }
 484
 485 #ifdef CONFIG_X86_64
 486 static void xen_load_gs_index(unsigned int idx)
 487 {
 488         if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
 489                 BUG();
 490 }
 491 #endif
 492
 493 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
 494                                 const void *ptr)
 495 {
 496         xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
 497         u64 entry = *(u64 *)ptr;
 498
 499         preempt_disable();
 500
 501         xen_mc_flush();
 502         if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
 503                 BUG();
 504
 505         preempt_enable();
 506 }
 507
 508 static int cvt_gate_to_trap(int vector, const gate_desc *val,
 509                             struct trap_info *info)
 510 {
 511         unsigned long addr;
 512
 513         if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
 514                 return 0;
 515
 516         info->vector = vector;
 517
 518         addr = gate_offset(*val);
 519 #ifdef CONFIG_X86_64
 520         /*
 521          * Look for known traps using IST, and substitute them
 522          * appropriately.  The debugger ones are the only ones we care
 523          * about.  Xen will handle faults like double_fault and
 524          * machine_check, so we should never see them.  Warn if
 525          * there's an unexpected IST-using fault handler.
 526          */
 527         if (addr == (unsigned long)debug)
 528                 addr = (unsigned long)xen_debug;
 529         else if (addr == (unsigned long)int3)
 530                 addr = (unsigned long)xen_int3;
 531         else if (addr == (unsigned long)stack_segment)
 532                 addr = (unsigned long)xen_stack_segment;
 533         else if (addr == (unsigned long)double_fault ||
 534                  addr == (unsigned long)nmi) {
 535                 /* Don't need to handle these */
 536                 return 0;
 537 #ifdef CONFIG_X86_MCE
 538         } else if (addr == (unsigned long)machine_check) {
 539                 return 0;
 540 #endif
 541         } else {
 542                 /* Some other trap using IST? */
 543                 if (WARN_ON(val->ist != 0))
 544                         return 0;
 545         }
 546 #endif  /* CONFIG_X86_64 */
 547         info->address = addr;
 548
 549         info->cs = gate_segment(*val);
 550         info->flags = val->dpl;
 551         /* interrupt gates clear IF */
 552         if (val->type == GATE_INTERRUPT)
 553                 info->flags |= 1 << 2;
 554
 555         return 1;
 556 }
 557
 558 /* Locations of each CPU's IDT */
 559 static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
 560
 561 /* Set an IDT entry.  If the entry is part of the current IDT, then
 562    also update Xen. */
 563 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
 564 {
 565         unsigned long p = (unsigned long)&dt[entrynum];
 566         unsigned long start, end;
 567
 568         preempt_disable();
 569
 570         start = __get_cpu_var(idt_desc).address;
 571         end = start + __get_cpu_var(idt_desc).size + 1;
 572
 573         xen_mc_flush();
 574
 575         native_write_idt_entry(dt, entrynum, g);
 576
 577         if (p >= start && (p + 8) <= end) {
 578                 struct trap_info info[2];
 579
 580                 info[1].address = 0;
 581
 582                 if (cvt_gate_to_trap(entrynum, g, &info[0]))
 583                         if (HYPERVISOR_set_trap_table(info))
 584                                 BUG();
 585         }
 586
 587         preempt_enable();
 588 }
 589
 590 static void xen_convert_trap_info(const struct desc_ptr *desc,
 591                                   struct trap_info *traps)
 592 {
 593         unsigned in, out, count;
 594
 595         count = (desc->size+1) / sizeof(gate_desc);
 596         BUG_ON(count > 256);
 597
 598         for (in = out = 0; in < count; in++) {
 599                 gate_desc *entry = (gate_desc*)(desc->address) + in;
 600
 601                 if (cvt_gate_to_trap(in, entry, &traps[out]))
 602                         out++;
 603         }
 604         traps[out].address = 0;
 605 }
 606
 607 void xen_copy_trap_info(struct trap_info *traps)
 608 {
 609         const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
 610
 611         xen_convert_trap_info(desc, traps);
 612 }
 613
 614 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
 615    hold a spinlock to protect the static traps[] array (static because
 616    it avoids allocation, and saves stack space). */
 617 static void xen_load_idt(const struct desc_ptr *desc)
 618 {
 619         static DEFINE_SPINLOCK(lock);
 620         static struct trap_info traps[257];
 621
 622         spin_lock(&lock);
 623
 624         __get_cpu_var(idt_desc) = *desc;
 625
 626         xen_convert_trap_info(desc, traps);
 627
 628         xen_mc_flush();
 629         if (HYPERVISOR_set_trap_table(traps))
 630                 BUG();
 631
 632         spin_unlock(&lock);
 633 }
 634
 635 /* Write a GDT descriptor entry.  Ignore LDT descriptors, since
 636    they're handled differently. */
 637 static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
 638                                 const void *desc, int type)
 639 {
 640         preempt_disable();
 641
 642         switch (type) {
 643         case DESC_LDT:
 644         case DESC_TSS:
 645                 /* ignore */
 646                 break;
 647
 648         default: {
 649                 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
 650
 651                 xen_mc_flush();
 652                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
 653                         BUG();
 654         }
 655
 656         }
 657
 658         preempt_enable();
 659 }
 660
 661 /*
 662  * Version of write_gdt_entry for use at early boot-time needed to
 663  * update an entry as simply as possible.
 664  */
 665 static __init void xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
 666                                             const void *desc, int type)
 667 {
 668         switch (type) {
 669         case DESC_LDT:
 670         case DESC_TSS:
 671                 /* ignore */
 672                 break;
 673
 674         default: {
 675                 xmaddr_t maddr = virt_to_machine(&dt[entry]);
 676
 677                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
 678                         dt[entry] = *(struct desc_struct *)desc;
 679         }
 680
 681         }
 682 }
 683
 684 static void xen_load_sp0(struct tss_struct *tss,
 685                          struct thread_struct *thread)
 686 {
 687         struct multicall_space mcs = xen_mc_entry(0);
 688         MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
 689         xen_mc_issue(PARAVIRT_LAZY_CPU);
 690 }
 691
 692 static void xen_set_iopl_mask(unsigned mask)
 693 {
 694         struct physdev_set_iopl set_iopl;
 695
 696         /* Force the change at ring 0. */
 697         set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
 698         HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 699 }
 700
 701 static void xen_io_delay(void)
 702 {
 703 }
 704
 705 #ifdef CONFIG_X86_LOCAL_APIC
 706 static u32 xen_apic_read(u32 reg)
 707 {
 708         return 0;
 709 }
 710
 711 static void xen_apic_write(u32 reg, u32 val)
 712 {
 713         /* Warn to see if there's any stray references */
 714         WARN_ON(1);
 715 }
 716
 717 static u64 xen_apic_icr_read(void)
 718 {
 719         return 0;
 720 }
 721
 722 static void xen_apic_icr_write(u32 low, u32 id)
 723 {
 724         /* Warn to see if there's any stray references */
 725         WARN_ON(1);
 726 }
 727
 728 static void xen_apic_wait_icr_idle(void)
 729 {
 730         return;
 731 }
 732
 733 static u32 xen_safe_apic_wait_icr_idle(void)
 734 {
 735         return 0;
 736 }
 737
 738 static void set_xen_basic_apic_ops(void)
 739 {
 740         apic->read = xen_apic_read;
 741         apic->write = xen_apic_write;
 742         apic->icr_read = xen_apic_icr_read;
 743         apic->icr_write = xen_apic_icr_write;
 744         apic->wait_icr_idle = xen_apic_wait_icr_idle;
 745         apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
 746 }
 747
 748 #endif
 749
 750 static void xen_clts(void)
 751 {
 752         struct multicall_space mcs;
 753
 754         mcs = xen_mc_entry(0);
 755
 756         MULTI_fpu_taskswitch(mcs.mc, 0);
 757
 758         xen_mc_issue(PARAVIRT_LAZY_CPU);
 759 }
 760
 761 static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
 762
 763 static unsigned long xen_read_cr0(void)
 764 {
 765         unsigned long cr0 = percpu_read(xen_cr0_value);
 766
 767         if (unlikely(cr0 == 0)) {
 768                 cr0 = native_read_cr0();
 769                 percpu_write(xen_cr0_value, cr0);
 770         }
 771
 772         return cr0;
 773 }
 774
 775 static void xen_write_cr0(unsigned long cr0)
 776 {
 777         struct multicall_space mcs;
 778
 779         percpu_write(xen_cr0_value, cr0);
 780
 781         /* Only pay attention to cr0.TS; everything else is
 782            ignored. */
 783         mcs = xen_mc_entry(0);
 784
 785         MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
 786
 787         xen_mc_issue(PARAVIRT_LAZY_CPU);
 788 }
 789
 790 static void xen_write_cr4(unsigned long cr4)
 791 {
 792         cr4 &= ~X86_CR4_PGE;
 793         cr4 &= ~X86_CR4_PSE;
 794
 795         native_write_cr4(cr4);
 796 }
 797
 798 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
 799 {
 800         int ret;
 801
 802         ret = 0;
 803
 804         switch (msr) {
 805 #ifdef CONFIG_X86_64
 806                 unsigned which;
 807                 u64 base;
 808
 809         case MSR_FS_BASE:               which = SEGBASE_FS; goto set;
 810         case MSR_KERNEL_GS_BASE:        which = SEGBASE_GS_USER; goto set;
 811         case MSR_GS_BASE:               which = SEGBASE_GS_KERNEL; goto set;
 812
 813         set:
 814                 base = ((u64)high << 32) | low;
 815                 if (HYPERVISOR_set_segment_base(which, base) != 0)
 816                         ret = -EIO;
 817                 break;
 818 #endif
 819
 820         case MSR_STAR:
 821         case MSR_CSTAR:
 822         case MSR_LSTAR:
 823         case MSR_SYSCALL_MASK:
 824         case MSR_IA32_SYSENTER_CS:
 825         case MSR_IA32_SYSENTER_ESP:
 826         case MSR_IA32_SYSENTER_EIP:
 827                 /* Fast syscall setup is all done in hypercalls, so
 828                    these are all ignored.  Stub them out here to stop
 829                    Xen console noise. */
 830                 break;
 831
 832         case MSR_IA32_CR_PAT:
 833                 if (smp_processor_id() == 0)
 834                         xen_set_pat(((u64)high << 32) | low);
 835                 break;
 836
 837         default:
 838                 ret = native_write_msr_safe(msr, low, high);
 839         }
 840
 841         return ret;
 842 }
 843
 844 void xen_setup_shared_info(void)
 845 {
 846         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 847                 set_fixmap(FIX_PARAVIRT_BOOTMAP,
 848                            xen_start_info->shared_info);
 849
 850                 HYPERVISOR_shared_info =
 851                         (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
 852         } else
 853                 HYPERVISOR_shared_info =
 854                         (struct shared_info *)__va(xen_start_info->shared_info);
 855
 856 #ifndef CONFIG_SMP
 857         /* In UP this is as good a place as any to set up shared info */
 858         xen_setup_vcpu_info_placement();
 859 #endif
 860
 861         xen_setup_mfn_list_list();
 862 }
 863
 864 /* This is called once we have the cpu_possible_map */
 865 void xen_setup_vcpu_info_placement(void)
 866 {
 867         int cpu;
 868
 869         for_each_possible_cpu(cpu)
 870                 xen_vcpu_setup(cpu);
 871
 872         /* xen_vcpu_setup managed to place the vcpu_info within the
 873            percpu area for all cpus, so make use of it */
 874         if (have_vcpu_info_placement) {
 875                 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
 876                 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
 877                 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
 878                 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
 879                 pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
 880         }
 881 }
 882
 883 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
 884                           unsigned long addr, unsigned len)
 885 {
 886         char *start, *end, *reloc;
 887         unsigned ret;
 888
 889         start = end = reloc = NULL;
 890
 891 #define SITE(op, x)                                                     \
 892         case PARAVIRT_PATCH(op.x):                                      \
 893         if (have_vcpu_info_placement) {                                 \
 894                 start = (char *)xen_##x##_direct;                       \
 895                 end = xen_##x##_direct_end;                             \
 896                 reloc = xen_##x##_direct_reloc;                         \
 897         }                                                               \
 898         goto patch_site
 899
 900         switch (type) {
 901                 SITE(pv_irq_ops, irq_enable);
 902                 SITE(pv_irq_ops, irq_disable);
 903                 SITE(pv_irq_ops, save_fl);
 904                 SITE(pv_irq_ops, restore_fl);
 905 #undef SITE
 906
 907         patch_site:
 908                 if (start == NULL || (end-start) > len)
 909                         goto default_patch;
 910
 911                 ret = paravirt_patch_insns(insnbuf, len, start, end);
 912
 913                 /* Note: because reloc is assigned from something that
 914                    appears to be an array, gcc assumes it's non-null,
 915                    but doesn't know its relationship with start and
 916                    end. */
 917                 if (reloc > start && reloc < end) {
 918                         int reloc_off = reloc - start;
 919                         long *relocp = (long *)(insnbuf + reloc_off);
 920                         long delta = start - (char *)addr;
 921
 922                         *relocp += delta;
 923                 }
 924                 break;
 925
 926         default_patch:
 927         default:
 928                 ret = paravirt_patch_default(type, clobbers, insnbuf,
 929                                              addr, len);
 930                 break;
 931         }
 932
 933         return ret;
 934 }
 935
 936 static const struct pv_info xen_info __initdata = {
 937         .paravirt_enabled = 1,
 938         .shared_kernel_pmd = 0,
 939
 940         .name = "Xen",
 941 };
 942
 943 static const struct pv_init_ops xen_init_ops __initdata = {
 944         .patch = xen_patch,
 945 };
 946
 947 static const struct pv_cpu_ops xen_cpu_ops __initdata = {
 948         .cpuid = xen_cpuid,
 949
 950         .set_debugreg = xen_set_debugreg,
 951         .get_debugreg = xen_get_debugreg,
 952
 953         .clts = xen_clts,
 954
 955         .read_cr0 = xen_read_cr0,
 956         .write_cr0 = xen_write_cr0,
 957
 958         .read_cr4 = native_read_cr4,
 959         .read_cr4_safe = native_read_cr4_safe,
 960         .write_cr4 = xen_write_cr4,
 961
 962         .wbinvd = native_wbinvd,
 963
 964         .read_msr = native_read_msr_safe,
 965         .write_msr = xen_write_msr_safe,
 966         .read_tsc = native_read_tsc,
 967         .read_pmc = native_read_pmc,
 968
 969         .iret = xen_iret,
 970         .irq_enable_sysexit = xen_sysexit,
 971 #ifdef CONFIG_X86_64
 972         .usergs_sysret32 = xen_sysret32,
 973         .usergs_sysret64 = xen_sysret64,
 974 #endif
 975
 976         .load_tr_desc = paravirt_nop,
 977         .set_ldt = xen_set_ldt,
 978         .load_gdt = xen_load_gdt,
 979         .load_idt = xen_load_idt,
 980         .load_tls = xen_load_tls,
 981 #ifdef CONFIG_X86_64
 982         .load_gs_index = xen_load_gs_index,
 983 #endif
 984
 985         .alloc_ldt = xen_alloc_ldt,
 986         .free_ldt = xen_free_ldt,
 987
 988         .store_gdt = native_store_gdt,
 989         .store_idt = native_store_idt,
 990         .store_tr = xen_store_tr,
 991
 992         .write_ldt_entry = xen_write_ldt_entry,
 993         .write_gdt_entry = xen_write_gdt_entry,
 994         .write_idt_entry = xen_write_idt_entry,
 995         .load_sp0 = xen_load_sp0,
 996
 997         .set_iopl_mask = xen_set_iopl_mask,
 998         .io_delay = xen_io_delay,
 999
1000         /* Xen takes care of %gs when switching to usermode for us */
1001         .swapgs = paravirt_nop,
1002
1003         .start_context_switch = paravirt_start_context_switch,
1004         .end_context_switch = xen_end_context_switch,
1005 };
1006
1007 static const struct pv_apic_ops xen_apic_ops __initdata = {
1008 #ifdef CONFIG_X86_LOCAL_APIC
1009         .startup_ipi_hook = paravirt_nop,
1010 #endif
1011 };
1012
1013 static void xen_reboot(int reason)
1014 {
1015         struct sched_shutdown r = { .reason = reason };
1016
1017 #ifdef CONFIG_SMP
1018         stop_other_cpus();
1019 #endif
1020
1021         if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
1022                 BUG();
1023 }
1024
1025 static void xen_restart(char *msg)
1026 {
1027         xen_reboot(SHUTDOWN_reboot);
1028 }
1029
1030 static void xen_emergency_restart(void)
1031 {
1032         xen_reboot(SHUTDOWN_reboot);
1033 }
1034
1035 static void xen_machine_halt(void)
1036 {
1037         xen_reboot(SHUTDOWN_poweroff);
1038 }
1039
1040 static void xen_crash_shutdown(struct pt_regs *regs)
1041 {
1042         xen_reboot(SHUTDOWN_crash);
1043 }
1044
1045 static int
1046 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
1047 {
1048         xen_reboot(SHUTDOWN_crash);
1049         return NOTIFY_DONE;
1050 }
1051
1052 static struct notifier_block xen_panic_block = {
1053         .notifier_call= xen_panic_event,
1054 };
1055
1056 int xen_panic_handler_init(void)
1057 {
1058         atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
1059         return 0;
1060 }
1061
1062 static const struct machine_ops __initdata xen_machine_ops = {
1063         .restart = xen_restart,
1064         .halt = xen_machine_halt,
1065         .power_off = xen_machine_halt,
1066         .shutdown = xen_machine_halt,
1067         .crash_shutdown = xen_crash_shutdown,
1068         .emergency_restart = xen_emergency_restart,
1069 };
1070
1071 /*
1072  * Set up the GDT and segment registers for -fstack-protector.  Until
1073  * we do this, we have to be careful not to call any stack-protected
1074  * function, which is most of the kernel.
1075  */
1076 static void __init xen_setup_stackprotector(void)
1077 {
1078         pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot;
1079         pv_cpu_ops.load_gdt = xen_load_gdt_boot;
1080
1081         setup_stack_canary_segment(0);
1082         switch_to_new_gdt(0);
1083
1084         pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry;
1085         pv_cpu_ops.load_gdt = xen_load_gdt;
1086 }
1087
1088 /* First C function to be called on Xen boot */
1089 asmlinkage void __init xen_start_kernel(void)
1090 {
1091         pgd_t *pgd;
1092
1093         if (!xen_start_info)
1094                 return;
1095
1096         xen_domain_type = XEN_PV_DOMAIN;
1097
1098         /* Install Xen paravirt ops */
1099         pv_info = xen_info;
1100         pv_init_ops = xen_init_ops;
1101         pv_cpu_ops = xen_cpu_ops;
1102         pv_apic_ops = xen_apic_ops;
1103
1104         x86_init.resources.memory_setup = xen_memory_setup;
1105         x86_init.oem.arch_setup = xen_arch_setup;
1106         x86_init.oem.banner = xen_banner;
1107
1108         xen_init_time_ops();
1109
1110         /*
1111          * Set up some pagetable state before starting to set any ptes.
1112          */
1113
1114         xen_init_mmu_ops();
1115
1116         /* Prevent unwanted bits from being set in PTEs. */
1117         __supported_pte_mask &= ~_PAGE_GLOBAL;
1118         if (!xen_initial_domain())
1119                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1120
1121         __supported_pte_mask |= _PAGE_IOMAP;
1122
1123         /*
1124          * Prevent page tables from being allocated in highmem, even
1125          * if CONFIG_HIGHPTE is enabled.
1126          */
1127         __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
1128
1129         /* Work out if we support NX */
1130         x86_configure_nx();
1131
1132         xen_setup_features();
1133
1134         /* Get mfn list */
1135         if (!xen_feature(XENFEAT_auto_translated_physmap))
1136                 xen_build_dynamic_phys_to_machine();
1137
1138         /*
1139          * Set up kernel GDT and segment registers, mainly so that
1140          * -fstack-protector code can be executed.
1141          */
1142         xen_setup_stackprotector();
1143
1144         xen_init_irq_ops();
1145         xen_init_cpuid_mask();
1146
1147 #ifdef CONFIG_X86_LOCAL_APIC
1148         /*
1149          * set up the basic apic ops.
1150          */
1151         set_xen_basic_apic_ops();
1152 #endif
1153
1154         if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
1155                 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
1156                 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
1157         }
1158
1159         machine_ops = xen_machine_ops;
1160
1161         /*
1162          * The only reliable way to retain the initial address of the
1163          * percpu gdt_page is to remember it here, so we can go and
1164          * mark it RW later, when the initial percpu area is freed.
1165          */
1166         xen_initial_gdt = &per_cpu(gdt_page, 0);
1167
1168         xen_smp_init();
1169
1170         pgd = (pgd_t *)xen_start_info->pt_base;
1171
1172         if (!xen_initial_domain())
1173                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1174
1175         __supported_pte_mask |= _PAGE_IOMAP;
1176         /* Don't do the full vcpu_info placement stuff until we have a
1177            possible map and a non-dummy shared_info. */
1178         per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
1179
1180         local_irq_disable();
1181         early_boot_irqs_off();
1182
1183         memblock_init();
1184
1185         xen_raw_console_write("mapping kernel into physical memory\n");
1186         pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
1187
1188         /* Allocate and initialize top and mid mfn levels for p2m structure */
1189         xen_build_mfn_list_list();
1190
1191         init_mm.pgd = pgd;
1192
1193         /* keep using Xen gdt for now; no urgent need to change it */
1194
1195 #ifdef CONFIG_X86_32
1196         pv_info.kernel_rpl = 1;
1197         if (xen_feature(XENFEAT_supervisor_mode_kernel))
1198                 pv_info.kernel_rpl = 0;
1199 #else
1200         pv_info.kernel_rpl = 0;
1201 #endif
1202
1203         /* set the limit of our address space */
1204         xen_reserve_top();
1205
1206 #ifdef CONFIG_X86_32
1207         /* set up basic CPUID stuff */
1208         cpu_detect(&new_cpu_data);
1209         new_cpu_data.hard_math = 1;
1210         new_cpu_data.wp_works_ok = 1;
1211         new_cpu_data.x86_capability[0] = cpuid_edx(1);
1212 #endif
1213
1214         /* Poke various useful things into boot_params */
1215         boot_params.hdr.type_of_loader = (9 << 4) | 0;
1216         boot_params.hdr.ramdisk_image = xen_start_info->mod_start
1217                 ? __pa(xen_start_info->mod_start) : 0;
1218         boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
1219         boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
1220
1221         if (!xen_initial_domain()) {
1222                 add_preferred_console("xenboot", 0, NULL);
1223                 add_preferred_console("tty", 0, NULL);
1224                 add_preferred_console("hvc", 0, NULL);
1225         } else {
1226                 /* Make sure ACS will be enabled */
1227                 pci_request_acs();
1228         }
1229
1230
1231         xen_raw_console_write("about to get started...\n");
1232
1233         xen_setup_runstate_info(0);
1234
1235         /* Start the world */
1236 #ifdef CONFIG_X86_32
1237         i386_start_kernel();
1238 #else
1239         x86_64_start_reservations((char *)__pa_symbol(&boot_params));
1240 #endif
1241 }
1242
1243 static uint32_t xen_cpuid_base(void)
1244 {
1245         uint32_t base, eax, ebx, ecx, edx;
1246         char signature[13];
1247
1248         for (base = 0x40000000; base < 0x40010000; base += 0x100) {
1249                 cpuid(base, &eax, &ebx, &ecx, &edx);
1250                 *(uint32_t *)(signature + 0) = ebx;
1251                 *(uint32_t *)(signature + 4) = ecx;
1252                 *(uint32_t *)(signature + 8) = edx;
1253                 signature[12] = 0;
1254
1255                 if (!strcmp("XenVMMXenVMM", signature) && ((eax - base) >= 2))
1256                         return base;
1257         }
1258
1259         return 0;
1260 }
1261
1262 static int init_hvm_pv_info(int *major, int *minor)
1263 {
1264         uint32_t eax, ebx, ecx, edx, pages, msr, base;
1265         u64 pfn;
1266
1267         base = xen_cpuid_base();
1268         cpuid(base + 1, &eax, &ebx, &ecx, &edx);
1269
1270         *major = eax >> 16;
1271         *minor = eax & 0xffff;
1272         printk(KERN_INFO "Xen version %d.%d.\n", *major, *minor);
1273
1274         cpuid(base + 2, &pages, &msr, &ecx, &edx);
1275
1276         pfn = __pa(hypercall_page);
1277         wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
1278
1279         xen_setup_features();
1280
1281         pv_info = xen_info;
1282         pv_info.kernel_rpl = 0;
1283
1284         xen_domain_type = XEN_HVM_DOMAIN;
1285
1286         return 0;
1287 }
1288
1289 void xen_hvm_init_shared_info(void)
1290 {
1291         int cpu;
1292         struct xen_add_to_physmap xatp;
1293         static struct shared_info *shared_info_page = 0;
1294
1295         if (!shared_info_page)
1296                 shared_info_page = (struct shared_info *)
1297                         extend_brk(PAGE_SIZE, PAGE_SIZE);
1298         xatp.domid = DOMID_SELF;
1299         xatp.idx = 0;
1300         xatp.space = XENMAPSPACE_shared_info;
1301         xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
1302         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
1303                 BUG();
1304
1305         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
1306
1307         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1308          * page, we use it in the event channel upcall and in some pvclock
1309          * related functions. We don't need the vcpu_info placement
1310          * optimizations because we don't use any pv_mmu or pv_irq op on
1311          * HVM.
1312          * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1313          * online but xen_hvm_init_shared_info is run at resume time too and
1314          * in that case multiple vcpus might be online. */
1315         for_each_online_cpu(cpu) {
1316                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1317         }
1318 }
1319
1320 #ifdef CONFIG_XEN_PVHVM
1321 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
1322                                     unsigned long action, void *hcpu)
1323 {
1324         int cpu = (long)hcpu;
1325         switch (action) {
1326         case CPU_UP_PREPARE:
1327                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1328                 break;
1329         default:
1330                 break;
1331         }
1332         return NOTIFY_OK;
1333 }
1334
1335 static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier = {
1336         .notifier_call  = xen_hvm_cpu_notify,
1337 };
1338
1339 static void __init xen_hvm_guest_init(void)
1340 {
1341         int r;
1342         int major, minor;
1343
1344         r = init_hvm_pv_info(&major, &minor);
1345         if (r < 0)
1346                 return;
1347
1348         xen_hvm_init_shared_info();
1349
1350         if (xen_feature(XENFEAT_hvm_callback_vector))
1351                 xen_have_vector_callback = 1;
1352         register_cpu_notifier(&xen_hvm_cpu_notifier);
1353         xen_unplug_emulated_devices();
1354         have_vcpu_info_placement = 0;
1355         x86_init.irqs.intr_init = xen_init_IRQ;
1356         xen_hvm_init_time_ops();
1357         xen_hvm_init_mmu_ops();
1358 }
1359
1360 static bool __init xen_hvm_platform(void)
1361 {
1362         if (xen_pv_domain())
1363                 return false;
1364
1365         if (!xen_cpuid_base())
1366                 return false;
1367
1368         return true;
1369 }
1370
1371 const __refconst struct hypervisor_x86 x86_hyper_xen_hvm = {
1372         .name                   = "Xen HVM",
1373         .detect                 = xen_hvm_platform,
1374         .init_platform          = xen_hvm_guest_init,
1375 };
1376 EXPORT_SYMBOL(x86_hyper_xen_hvm);
1377 #endif