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/pci.h>
  50 #include <asm/xen/hypercall.h>
  51 #include <asm/xen/hypervisor.h>
  52 #include <asm/fixmap.h>
  53 #include <asm/processor.h>
  54 #include <asm/proto.h>
  55 #include <asm/msr-index.h>
  56 #include <asm/traps.h>
  57 #include <asm/setup.h>
  58 #include <asm/desc.h>
  59 #include <asm/pgalloc.h>
  60 #include <asm/pgtable.h>
  61 #include <asm/tlbflush.h>
  62 #include <asm/reboot.h>
  63 #include <asm/stackprotector.h>
  64 #include <asm/hypervisor.h>
  65
  66 #include "xen-ops.h"
  67 #include "mmu.h"
  68 #include "multicalls.h"
  69
  70 EXPORT_SYMBOL_GPL(hypercall_page);
  71
  72 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
  73 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
  74
  75 enum xen_domain_type xen_domain_type = XEN_NATIVE;
  76 EXPORT_SYMBOL_GPL(xen_domain_type);
  77
  78 unsigned long *machine_to_phys_mapping = (void *)MACH2PHYS_VIRT_START;
  79 EXPORT_SYMBOL(machine_to_phys_mapping);
  80 unsigned int   machine_to_phys_order;
  81 EXPORT_SYMBOL(machine_to_phys_order);
  82
  83 struct start_info *xen_start_info;
  84 EXPORT_SYMBOL_GPL(xen_start_info);
  85
  86 struct shared_info xen_dummy_shared_info;
  87
  88 void *xen_initial_gdt;
  89
  90 RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
  91 __read_mostly int xen_have_vector_callback;
  92 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
  93
  94 /*
  95  * Point at some empty memory to start with. We map the real shared_info
  96  * page as soon as fixmap is up and running.
  97  */
  98 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
  99
 100 /*
 101  * Flag to determine whether vcpu info placement is available on all
 102  * VCPUs.  We assume it is to start with, and then set it to zero on
 103  * the first failure.  This is because it can succeed on some VCPUs
 104  * and not others, since it can involve hypervisor memory allocation,
 105  * or because the guest failed to guarantee all the appropriate
 106  * constraints on all VCPUs (ie buffer can't cross a page boundary).
 107  *
 108  * Note that any particular CPU may be using a placed vcpu structure,
 109  * but we can only optimise if the all are.
 110  *
 111  * 0: not available, 1: available
 112  */
 113 static int have_vcpu_info_placement = 1;
 114
 115 static void clamp_max_cpus(void)
 116 {
 117 #ifdef CONFIG_SMP
 118         if (setup_max_cpus > MAX_VIRT_CPUS)
 119                 setup_max_cpus = MAX_VIRT_CPUS;
 120 #endif
 121 }
 122
 123 static void xen_vcpu_setup(int cpu)
 124 {
 125         struct vcpu_register_vcpu_info info;
 126         int err;
 127         struct vcpu_info *vcpup;
 128
 129         BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
 130
 131         if (cpu < MAX_VIRT_CPUS)
 132                 per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
 133
 134         if (!have_vcpu_info_placement) {
 135                 if (cpu >= MAX_VIRT_CPUS)
 136                         clamp_max_cpus();
 137                 return;
 138         }
 139
 140         vcpup = &per_cpu(xen_vcpu_info, cpu);
 141         info.mfn = arbitrary_virt_to_mfn(vcpup);
 142         info.offset = offset_in_page(vcpup);
 143
 144         /* Check to see if the hypervisor will put the vcpu_info
 145            structure where we want it, which allows direct access via
 146            a percpu-variable. */
 147         err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
 148
 149         if (err) {
 150                 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
 151                 have_vcpu_info_placement = 0;
 152                 clamp_max_cpus();
 153         } else {
 154                 /* This cpu is using the registered vcpu info, even if
 155                    later ones fail to. */
 156                 per_cpu(xen_vcpu, 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_MTRR) |  /* disable MTRR */
 246                   (1 << X86_FEATURE_ACC));   /* thermal monitoring */
 247
 248         if (!xen_initial_domain())
 249                 cpuid_leaf1_edx_mask &=
 250                         ~((1 << X86_FEATURE_APIC) |  /* disable local APIC */
 251                           (1 << X86_FEATURE_ACPI));  /* disable ACPI */
 252
 253         ax = 1;
 254         cx = 0;
 255         xen_cpuid(&ax, &bx, &cx, &dx);
 256
 257         /* cpuid claims we support xsave; try enabling it to see what happens */
 258         if (cx & (1 << (X86_FEATURE_XSAVE % 32))) {
 259                 unsigned long cr4;
 260
 261                 set_in_cr4(X86_CR4_OSXSAVE);
 262
 263                 cr4 = read_cr4();
 264
 265                 if ((cr4 & X86_CR4_OSXSAVE) == 0)
 266                         cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32));
 267
 268                 clear_in_cr4(X86_CR4_OSXSAVE);
 269         }
 270 }
 271
 272 static void xen_set_debugreg(int reg, unsigned long val)
 273 {
 274         HYPERVISOR_set_debugreg(reg, val);
 275 }
 276
 277 static unsigned long xen_get_debugreg(int reg)
 278 {
 279         return HYPERVISOR_get_debugreg(reg);
 280 }
 281
 282 static void xen_end_context_switch(struct task_struct *next)
 283 {
 284         xen_mc_flush();
 285         paravirt_end_context_switch(next);
 286 }
 287
 288 static unsigned long xen_store_tr(void)
 289 {
 290         return 0;
 291 }
 292
 293 /*
 294  * Set the page permissions for a particular virtual address.  If the
 295  * address is a vmalloc mapping (or other non-linear mapping), then
 296  * find the linear mapping of the page and also set its protections to
 297  * match.
 298  */
 299 static void set_aliased_prot(void *v, pgprot_t prot)
 300 {
 301         int level;
 302         pte_t *ptep;
 303         pte_t pte;
 304         unsigned long pfn;
 305         struct page *page;
 306
 307         ptep = lookup_address((unsigned long)v, &level);
 308         BUG_ON(ptep == NULL);
 309
 310         pfn = pte_pfn(*ptep);
 311         page = pfn_to_page(pfn);
 312
 313         pte = pfn_pte(pfn, prot);
 314
 315         if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
 316                 BUG();
 317
 318         if (!PageHighMem(page)) {
 319                 void *av = __va(PFN_PHYS(pfn));
 320
 321                 if (av != v)
 322                         if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
 323                                 BUG();
 324         } else
 325                 kmap_flush_unused();
 326 }
 327
 328 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
 329 {
 330         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
 331         int i;
 332
 333         for(i = 0; i < entries; i += entries_per_page)
 334                 set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
 335 }
 336
 337 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
 338 {
 339         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
 340         int i;
 341
 342         for(i = 0; i < entries; i += entries_per_page)
 343                 set_aliased_prot(ldt + i, PAGE_KERNEL);
 344 }
 345
 346 static void xen_set_ldt(const void *addr, unsigned entries)
 347 {
 348         struct mmuext_op *op;
 349         struct multicall_space mcs = xen_mc_entry(sizeof(*op));
 350
 351         op = mcs.args;
 352         op->cmd = MMUEXT_SET_LDT;
 353         op->arg1.linear_addr = (unsigned long)addr;
 354         op->arg2.nr_ents = entries;
 355
 356         MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
 357
 358         xen_mc_issue(PARAVIRT_LAZY_CPU);
 359 }
 360
 361 static void xen_load_gdt(const struct desc_ptr *dtr)
 362 {
 363         unsigned long va = dtr->address;
 364         unsigned int size = dtr->size + 1;
 365         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 366         unsigned long frames[pages];
 367         int f;
 368
 369         /*
 370          * A GDT can be up to 64k in size, which corresponds to 8192
 371          * 8-byte entries, or 16 4k pages..
 372          */
 373
 374         BUG_ON(size > 65536);
 375         BUG_ON(va & ~PAGE_MASK);
 376
 377         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 378                 int level;
 379                 pte_t *ptep;
 380                 unsigned long pfn, mfn;
 381                 void *virt;
 382
 383                 /*
 384                  * The GDT is per-cpu and is in the percpu data area.
 385                  * That can be virtually mapped, so we need to do a
 386                  * page-walk to get the underlying MFN for the
 387                  * hypercall.  The page can also be in the kernel's
 388                  * linear range, so we need to RO that mapping too.
 389                  */
 390                 ptep = lookup_address(va, &level);
 391                 BUG_ON(ptep == NULL);
 392
 393                 pfn = pte_pfn(*ptep);
 394                 mfn = pfn_to_mfn(pfn);
 395                 virt = __va(PFN_PHYS(pfn));
 396
 397                 frames[f] = mfn;
 398
 399                 make_lowmem_page_readonly((void *)va);
 400                 make_lowmem_page_readonly(virt);
 401         }
 402
 403         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
 404                 BUG();
 405 }
 406
 407 /*
 408  * load_gdt for early boot, when the gdt is only mapped once
 409  */
 410 static __init void xen_load_gdt_boot(const struct desc_ptr *dtr)
 411 {
 412         unsigned long va = dtr->address;
 413         unsigned int size = dtr->size + 1;
 414         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 415         unsigned long frames[pages];
 416         int f;
 417
 418         /*
 419          * A GDT can be up to 64k in size, which corresponds to 8192
 420          * 8-byte entries, or 16 4k pages..
 421          */
 422
 423         BUG_ON(size > 65536);
 424         BUG_ON(va & ~PAGE_MASK);
 425
 426         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 427                 pte_t pte;
 428                 unsigned long pfn, mfn;
 429
 430                 pfn = virt_to_pfn(va);
 431                 mfn = pfn_to_mfn(pfn);
 432
 433                 pte = pfn_pte(pfn, PAGE_KERNEL_RO);
 434
 435                 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
 436                         BUG();
 437
 438                 frames[f] = mfn;
 439         }
 440
 441         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
 442                 BUG();
 443 }
 444
 445 static void load_TLS_descriptor(struct thread_struct *t,
 446                                 unsigned int cpu, unsigned int i)
 447 {
 448         struct desc_struct *gdt = get_cpu_gdt_table(cpu);
 449         xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
 450         struct multicall_space mc = __xen_mc_entry(0);
 451
 452         MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
 453 }
 454
 455 static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 456 {
 457         /*
 458          * XXX sleazy hack: If we're being called in a lazy-cpu zone
 459          * and lazy gs handling is enabled, it means we're in a
 460          * context switch, and %gs has just been saved.  This means we
 461          * can zero it out to prevent faults on exit from the
 462          * hypervisor if the next process has no %gs.  Either way, it
 463          * has been saved, and the new value will get loaded properly.
 464          * This will go away as soon as Xen has been modified to not
 465          * save/restore %gs for normal hypercalls.
 466          *
 467          * On x86_64, this hack is not used for %gs, because gs points
 468          * to KERNEL_GS_BASE (and uses it for PDA references), so we
 469          * must not zero %gs on x86_64
 470          *
 471          * For x86_64, we need to zero %fs, otherwise we may get an
 472          * exception between the new %fs descriptor being loaded and
 473          * %fs being effectively cleared at __switch_to().
 474          */
 475         if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
 476 #ifdef CONFIG_X86_32
 477                 lazy_load_gs(0);
 478 #else
 479                 loadsegment(fs, 0);
 480 #endif
 481         }
 482
 483         xen_mc_batch();
 484
 485         load_TLS_descriptor(t, cpu, 0);
 486         load_TLS_descriptor(t, cpu, 1);
 487         load_TLS_descriptor(t, cpu, 2);
 488
 489         xen_mc_issue(PARAVIRT_LAZY_CPU);
 490 }
 491
 492 #ifdef CONFIG_X86_64
 493 static void xen_load_gs_index(unsigned int idx)
 494 {
 495         if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
 496                 BUG();
 497 }
 498 #endif
 499
 500 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
 501                                 const void *ptr)
 502 {
 503         xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
 504         u64 entry = *(u64 *)ptr;
 505
 506         preempt_disable();
 507
 508         xen_mc_flush();
 509         if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
 510                 BUG();
 511
 512         preempt_enable();
 513 }
 514
 515 static int cvt_gate_to_trap(int vector, const gate_desc *val,
 516                             struct trap_info *info)
 517 {
 518         unsigned long addr;
 519
 520         if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
 521                 return 0;
 522
 523         info->vector = vector;
 524
 525         addr = gate_offset(*val);
 526 #ifdef CONFIG_X86_64
 527         /*
 528          * Look for known traps using IST, and substitute them
 529          * appropriately.  The debugger ones are the only ones we care
 530          * about.  Xen will handle faults like double_fault and
 531          * machine_check, so we should never see them.  Warn if
 532          * there's an unexpected IST-using fault handler.
 533          */
 534         if (addr == (unsigned long)debug)
 535                 addr = (unsigned long)xen_debug;
 536         else if (addr == (unsigned long)int3)
 537                 addr = (unsigned long)xen_int3;
 538         else if (addr == (unsigned long)stack_segment)
 539                 addr = (unsigned long)xen_stack_segment;
 540         else if (addr == (unsigned long)double_fault ||
 541                  addr == (unsigned long)nmi) {
 542                 /* Don't need to handle these */
 543                 return 0;
 544 #ifdef CONFIG_X86_MCE
 545         } else if (addr == (unsigned long)machine_check) {
 546                 return 0;
 547 #endif
 548         } else {
 549                 /* Some other trap using IST? */
 550                 if (WARN_ON(val->ist != 0))
 551                         return 0;
 552         }
 553 #endif  /* CONFIG_X86_64 */
 554         info->address = addr;
 555
 556         info->cs = gate_segment(*val);
 557         info->flags = val->dpl;
 558         /* interrupt gates clear IF */
 559         if (val->type == GATE_INTERRUPT)
 560                 info->flags |= 1 << 2;
 561
 562         return 1;
 563 }
 564
 565 /* Locations of each CPU's IDT */
 566 static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
 567
 568 /* Set an IDT entry.  If the entry is part of the current IDT, then
 569    also update Xen. */
 570 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
 571 {
 572         unsigned long p = (unsigned long)&dt[entrynum];
 573         unsigned long start, end;
 574
 575         preempt_disable();
 576
 577         start = __get_cpu_var(idt_desc).address;
 578         end = start + __get_cpu_var(idt_desc).size + 1;
 579
 580         xen_mc_flush();
 581
 582         native_write_idt_entry(dt, entrynum, g);
 583
 584         if (p >= start && (p + 8) <= end) {
 585                 struct trap_info info[2];
 586
 587                 info[1].address = 0;
 588
 589                 if (cvt_gate_to_trap(entrynum, g, &info[0]))
 590                         if (HYPERVISOR_set_trap_table(info))
 591                                 BUG();
 592         }
 593
 594         preempt_enable();
 595 }
 596
 597 static void xen_convert_trap_info(const struct desc_ptr *desc,
 598                                   struct trap_info *traps)
 599 {
 600         unsigned in, out, count;
 601
 602         count = (desc->size+1) / sizeof(gate_desc);
 603         BUG_ON(count > 256);
 604
 605         for (in = out = 0; in < count; in++) {
 606                 gate_desc *entry = (gate_desc*)(desc->address) + in;
 607
 608                 if (cvt_gate_to_trap(in, entry, &traps[out]))
 609                         out++;
 610         }
 611         traps[out].address = 0;
 612 }
 613
 614 void xen_copy_trap_info(struct trap_info *traps)
 615 {
 616         const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
 617
 618         xen_convert_trap_info(desc, traps);
 619 }
 620
 621 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
 622    hold a spinlock to protect the static traps[] array (static because
 623    it avoids allocation, and saves stack space). */
 624 static void xen_load_idt(const struct desc_ptr *desc)
 625 {
 626         static DEFINE_SPINLOCK(lock);
 627         static struct trap_info traps[257];
 628
 629         spin_lock(&lock);
 630
 631         __get_cpu_var(idt_desc) = *desc;
 632
 633         xen_convert_trap_info(desc, traps);
 634
 635         xen_mc_flush();
 636         if (HYPERVISOR_set_trap_table(traps))
 637                 BUG();
 638
 639         spin_unlock(&lock);
 640 }
 641
 642 /* Write a GDT descriptor entry.  Ignore LDT descriptors, since
 643    they're handled differently. */
 644 static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
 645                                 const void *desc, int type)
 646 {
 647         preempt_disable();
 648
 649         switch (type) {
 650         case DESC_LDT:
 651         case DESC_TSS:
 652                 /* ignore */
 653                 break;
 654
 655         default: {
 656                 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
 657
 658                 xen_mc_flush();
 659                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
 660                         BUG();
 661         }
 662
 663         }
 664
 665         preempt_enable();
 666 }
 667
 668 /*
 669  * Version of write_gdt_entry for use at early boot-time needed to
 670  * update an entry as simply as possible.
 671  */
 672 static __init void xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
 673                                             const void *desc, int type)
 674 {
 675         switch (type) {
 676         case DESC_LDT:
 677         case DESC_TSS:
 678                 /* ignore */
 679                 break;
 680
 681         default: {
 682                 xmaddr_t maddr = virt_to_machine(&dt[entry]);
 683
 684                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
 685                         dt[entry] = *(struct desc_struct *)desc;
 686         }
 687
 688         }
 689 }
 690
 691 static void xen_load_sp0(struct tss_struct *tss,
 692                          struct thread_struct *thread)
 693 {
 694         struct multicall_space mcs = xen_mc_entry(0);
 695         MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
 696         xen_mc_issue(PARAVIRT_LAZY_CPU);
 697 }
 698
 699 static void xen_set_iopl_mask(unsigned mask)
 700 {
 701         struct physdev_set_iopl set_iopl;
 702
 703         /* Force the change at ring 0. */
 704         set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
 705         HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 706 }
 707
 708 static void xen_io_delay(void)
 709 {
 710 }
 711
 712 #ifdef CONFIG_X86_LOCAL_APIC
 713 static u32 xen_apic_read(u32 reg)
 714 {
 715         return 0;
 716 }
 717
 718 static void xen_apic_write(u32 reg, u32 val)
 719 {
 720         /* Warn to see if there's any stray references */
 721         WARN_ON(1);
 722 }
 723
 724 static u64 xen_apic_icr_read(void)
 725 {
 726         return 0;
 727 }
 728
 729 static void xen_apic_icr_write(u32 low, u32 id)
 730 {
 731         /* Warn to see if there's any stray references */
 732         WARN_ON(1);
 733 }
 734
 735 static void xen_apic_wait_icr_idle(void)
 736 {
 737         return;
 738 }
 739
 740 static u32 xen_safe_apic_wait_icr_idle(void)
 741 {
 742         return 0;
 743 }
 744
 745 static void set_xen_basic_apic_ops(void)
 746 {
 747         apic->read = xen_apic_read;
 748         apic->write = xen_apic_write;
 749         apic->icr_read = xen_apic_icr_read;
 750         apic->icr_write = xen_apic_icr_write;
 751         apic->wait_icr_idle = xen_apic_wait_icr_idle;
 752         apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
 753 }
 754
 755 #endif
 756
 757 static void xen_clts(void)
 758 {
 759         struct multicall_space mcs;
 760
 761         mcs = xen_mc_entry(0);
 762
 763         MULTI_fpu_taskswitch(mcs.mc, 0);
 764
 765         xen_mc_issue(PARAVIRT_LAZY_CPU);
 766 }
 767
 768 static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
 769
 770 static unsigned long xen_read_cr0(void)
 771 {
 772         unsigned long cr0 = percpu_read(xen_cr0_value);
 773
 774         if (unlikely(cr0 == 0)) {
 775                 cr0 = native_read_cr0();
 776                 percpu_write(xen_cr0_value, cr0);
 777         }
 778
 779         return cr0;
 780 }
 781
 782 static void xen_write_cr0(unsigned long cr0)
 783 {
 784         struct multicall_space mcs;
 785
 786         percpu_write(xen_cr0_value, cr0);
 787
 788         /* Only pay attention to cr0.TS; everything else is
 789            ignored. */
 790         mcs = xen_mc_entry(0);
 791
 792         MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
 793
 794         xen_mc_issue(PARAVIRT_LAZY_CPU);
 795 }
 796
 797 static void xen_write_cr4(unsigned long cr4)
 798 {
 799         cr4 &= ~X86_CR4_PGE;
 800         cr4 &= ~X86_CR4_PSE;
 801
 802         native_write_cr4(cr4);
 803 }
 804
 805 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
 806 {
 807         int ret;
 808
 809         ret = 0;
 810
 811         switch (msr) {
 812 #ifdef CONFIG_X86_64
 813                 unsigned which;
 814                 u64 base;
 815
 816         case MSR_FS_BASE:               which = SEGBASE_FS; goto set;
 817         case MSR_KERNEL_GS_BASE:        which = SEGBASE_GS_USER; goto set;
 818         case MSR_GS_BASE:               which = SEGBASE_GS_KERNEL; goto set;
 819
 820         set:
 821                 base = ((u64)high << 32) | low;
 822                 if (HYPERVISOR_set_segment_base(which, base) != 0)
 823                         ret = -EIO;
 824                 break;
 825 #endif
 826
 827         case MSR_STAR:
 828         case MSR_CSTAR:
 829         case MSR_LSTAR:
 830         case MSR_SYSCALL_MASK:
 831         case MSR_IA32_SYSENTER_CS:
 832         case MSR_IA32_SYSENTER_ESP:
 833         case MSR_IA32_SYSENTER_EIP:
 834                 /* Fast syscall setup is all done in hypercalls, so
 835                    these are all ignored.  Stub them out here to stop
 836                    Xen console noise. */
 837                 break;
 838
 839         case MSR_IA32_CR_PAT:
 840                 if (smp_processor_id() == 0)
 841                         xen_set_pat(((u64)high << 32) | low);
 842                 break;
 843
 844         default:
 845                 ret = native_write_msr_safe(msr, low, high);
 846         }
 847
 848         return ret;
 849 }
 850
 851 void xen_setup_shared_info(void)
 852 {
 853         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 854                 set_fixmap(FIX_PARAVIRT_BOOTMAP,
 855                            xen_start_info->shared_info);
 856
 857                 HYPERVISOR_shared_info =
 858                         (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
 859         } else
 860                 HYPERVISOR_shared_info =
 861                         (struct shared_info *)__va(xen_start_info->shared_info);
 862
 863 #ifndef CONFIG_SMP
 864         /* In UP this is as good a place as any to set up shared info */
 865         xen_setup_vcpu_info_placement();
 866 #endif
 867
 868         xen_setup_mfn_list_list();
 869 }
 870
 871 /* This is called once we have the cpu_possible_map */
 872 void xen_setup_vcpu_info_placement(void)
 873 {
 874         int cpu;
 875
 876         for_each_possible_cpu(cpu)
 877                 xen_vcpu_setup(cpu);
 878
 879         /* xen_vcpu_setup managed to place the vcpu_info within the
 880            percpu area for all cpus, so make use of it */
 881         if (have_vcpu_info_placement) {
 882                 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
 883                 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
 884                 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
 885                 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
 886                 pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
 887         }
 888 }
 889
 890 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
 891                           unsigned long addr, unsigned len)
 892 {
 893         char *start, *end, *reloc;
 894         unsigned ret;
 895
 896         start = end = reloc = NULL;
 897
 898 #define SITE(op, x)                                                     \
 899         case PARAVIRT_PATCH(op.x):                                      \
 900         if (have_vcpu_info_placement) {                                 \
 901                 start = (char *)xen_##x##_direct;                       \
 902                 end = xen_##x##_direct_end;                             \
 903                 reloc = xen_##x##_direct_reloc;                         \
 904         }                                                               \
 905         goto patch_site
 906
 907         switch (type) {
 908                 SITE(pv_irq_ops, irq_enable);
 909                 SITE(pv_irq_ops, irq_disable);
 910                 SITE(pv_irq_ops, save_fl);
 911                 SITE(pv_irq_ops, restore_fl);
 912 #undef SITE
 913
 914         patch_site:
 915                 if (start == NULL || (end-start) > len)
 916                         goto default_patch;
 917
 918                 ret = paravirt_patch_insns(insnbuf, len, start, end);
 919
 920                 /* Note: because reloc is assigned from something that
 921                    appears to be an array, gcc assumes it's non-null,
 922                    but doesn't know its relationship with start and
 923                    end. */
 924                 if (reloc > start && reloc < end) {
 925                         int reloc_off = reloc - start;
 926                         long *relocp = (long *)(insnbuf + reloc_off);
 927                         long delta = start - (char *)addr;
 928
 929                         *relocp += delta;
 930                 }
 931                 break;
 932
 933         default_patch:
 934         default:
 935                 ret = paravirt_patch_default(type, clobbers, insnbuf,
 936                                              addr, len);
 937                 break;
 938         }
 939
 940         return ret;
 941 }
 942
 943 static const struct pv_info xen_info __initdata = {
 944         .paravirt_enabled = 1,
 945         .shared_kernel_pmd = 0,
 946
 947         .name = "Xen",
 948 };
 949
 950 static const struct pv_init_ops xen_init_ops __initdata = {
 951         .patch = xen_patch,
 952 };
 953
 954 static const struct pv_cpu_ops xen_cpu_ops __initdata = {
 955         .cpuid = xen_cpuid,
 956
 957         .set_debugreg = xen_set_debugreg,
 958         .get_debugreg = xen_get_debugreg,
 959
 960         .clts = xen_clts,
 961
 962         .read_cr0 = xen_read_cr0,
 963         .write_cr0 = xen_write_cr0,
 964
 965         .read_cr4 = native_read_cr4,
 966         .read_cr4_safe = native_read_cr4_safe,
 967         .write_cr4 = xen_write_cr4,
 968
 969         .wbinvd = native_wbinvd,
 970
 971         .read_msr = native_read_msr_safe,
 972         .write_msr = xen_write_msr_safe,
 973         .read_tsc = native_read_tsc,
 974         .read_pmc = native_read_pmc,
 975
 976         .iret = xen_iret,
 977         .irq_enable_sysexit = xen_sysexit,
 978 #ifdef CONFIG_X86_64
 979         .usergs_sysret32 = xen_sysret32,
 980         .usergs_sysret64 = xen_sysret64,
 981 #endif
 982
 983         .load_tr_desc = paravirt_nop,
 984         .set_ldt = xen_set_ldt,
 985         .load_gdt = xen_load_gdt,
 986         .load_idt = xen_load_idt,
 987         .load_tls = xen_load_tls,
 988 #ifdef CONFIG_X86_64
 989         .load_gs_index = xen_load_gs_index,
 990 #endif
 991
 992         .alloc_ldt = xen_alloc_ldt,
 993         .free_ldt = xen_free_ldt,
 994
 995         .store_gdt = native_store_gdt,
 996         .store_idt = native_store_idt,
 997         .store_tr = xen_store_tr,
 998
 999         .write_ldt_entry = xen_write_ldt_entry,
1000         .write_gdt_entry = xen_write_gdt_entry,
1001         .write_idt_entry = xen_write_idt_entry,
1002         .load_sp0 = xen_load_sp0,
1003
1004         .set_iopl_mask = xen_set_iopl_mask,
1005         .io_delay = xen_io_delay,
1006
1007         /* Xen takes care of %gs when switching to usermode for us */
1008         .swapgs = paravirt_nop,
1009
1010         .start_context_switch = paravirt_start_context_switch,
1011         .end_context_switch = xen_end_context_switch,
1012 };
1013
1014 static const struct pv_apic_ops xen_apic_ops __initdata = {
1015 #ifdef CONFIG_X86_LOCAL_APIC
1016         .startup_ipi_hook = paravirt_nop,
1017 #endif
1018 };
1019
1020 static void xen_reboot(int reason)
1021 {
1022         struct sched_shutdown r = { .reason = reason };
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         struct physdev_set_iopl set_iopl;
1095         int rc;
1096         pgd_t *pgd;
1097
1098         if (!xen_start_info)
1099                 return;
1100
1101         xen_domain_type = XEN_PV_DOMAIN;
1102
1103         xen_setup_machphys_mapping();
1104
1105         /* Install Xen paravirt ops */
1106         pv_info = xen_info;
1107         pv_init_ops = xen_init_ops;
1108         pv_cpu_ops = xen_cpu_ops;
1109         pv_apic_ops = xen_apic_ops;
1110
1111         x86_init.resources.memory_setup = xen_memory_setup;
1112         x86_init.oem.arch_setup = xen_arch_setup;
1113         x86_init.oem.banner = xen_banner;
1114
1115         xen_init_time_ops();
1116
1117         /*
1118          * Set up some pagetable state before starting to set any ptes.
1119          */
1120
1121         xen_init_mmu_ops();
1122
1123         /* Prevent unwanted bits from being set in PTEs. */
1124         __supported_pte_mask &= ~_PAGE_GLOBAL;
1125         if (!xen_initial_domain())
1126                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1127
1128         __supported_pte_mask |= _PAGE_IOMAP;
1129
1130         /*
1131          * Prevent page tables from being allocated in highmem, even
1132          * if CONFIG_HIGHPTE is enabled.
1133          */
1134         __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
1135
1136         /* Work out if we support NX */
1137         x86_configure_nx();
1138
1139         xen_setup_features();
1140
1141         /* Get mfn list */
1142         if (!xen_feature(XENFEAT_auto_translated_physmap))
1143                 xen_build_dynamic_phys_to_machine();
1144
1145         /*
1146          * Set up kernel GDT and segment registers, mainly so that
1147          * -fstack-protector code can be executed.
1148          */
1149         xen_setup_stackprotector();
1150
1151         xen_init_irq_ops();
1152         xen_init_cpuid_mask();
1153
1154 #ifdef CONFIG_X86_LOCAL_APIC
1155         /*
1156          * set up the basic apic ops.
1157          */
1158         set_xen_basic_apic_ops();
1159 #endif
1160
1161         if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
1162                 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
1163                 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
1164         }
1165
1166         machine_ops = xen_machine_ops;
1167
1168         /*
1169          * The only reliable way to retain the initial address of the
1170          * percpu gdt_page is to remember it here, so we can go and
1171          * mark it RW later, when the initial percpu area is freed.
1172          */
1173         xen_initial_gdt = &per_cpu(gdt_page, 0);
1174
1175         xen_smp_init();
1176
1177         pgd = (pgd_t *)xen_start_info->pt_base;
1178
1179         if (!xen_initial_domain())
1180                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1181
1182         __supported_pte_mask |= _PAGE_IOMAP;
1183         /* Don't do the full vcpu_info placement stuff until we have a
1184            possible map and a non-dummy shared_info. */
1185         per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
1186
1187         local_irq_disable();
1188         early_boot_irqs_off();
1189
1190         memblock_init();
1191
1192         xen_raw_console_write("mapping kernel into physical memory\n");
1193         pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
1194         xen_ident_map_ISA();
1195
1196         /* Allocate and initialize top and mid mfn levels for p2m structure */
1197         xen_build_mfn_list_list();
1198
1199         /* keep using Xen gdt for now; no urgent need to change it */
1200
1201 #ifdef CONFIG_X86_32
1202         pv_info.kernel_rpl = 1;
1203         if (xen_feature(XENFEAT_supervisor_mode_kernel))
1204                 pv_info.kernel_rpl = 0;
1205 #else
1206         pv_info.kernel_rpl = 0;
1207 #endif
1208         /* set the limit of our address space */
1209         xen_reserve_top();
1210
1211         /* We used to do this in xen_arch_setup, but that is too late on AMD
1212          * were early_cpu_init (run before ->arch_setup()) calls early_amd_init
1213          * which pokes 0xcf8 port.
1214          */
1215         set_iopl.iopl = 1;
1216         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
1217         if (rc != 0)
1218                 xen_raw_printk("physdev_op failed %d\n", rc);
1219
1220 #ifdef CONFIG_X86_32
1221         /* set up basic CPUID stuff */
1222         cpu_detect(&new_cpu_data);
1223         new_cpu_data.hard_math = 1;
1224         new_cpu_data.wp_works_ok = 1;
1225         new_cpu_data.x86_capability[0] = cpuid_edx(1);
1226 #endif
1227
1228         /* Poke various useful things into boot_params */
1229         boot_params.hdr.type_of_loader = (9 << 4) | 0;
1230         boot_params.hdr.ramdisk_image = xen_start_info->mod_start
1231                 ? __pa(xen_start_info->mod_start) : 0;
1232         boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
1233         boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
1234
1235         if (!xen_initial_domain()) {
1236                 add_preferred_console("xenboot", 0, NULL);
1237                 add_preferred_console("tty", 0, NULL);
1238                 add_preferred_console("hvc", 0, NULL);
1239                 if (pci_xen)
1240                         x86_init.pci.arch_init = pci_xen_init;
1241         } else {
1242                 /* Make sure ACS will be enabled */
1243                 pci_request_acs();
1244         }
1245
1246
1247         xen_raw_console_write("about to get started...\n");
1248
1249         xen_setup_runstate_info(0);
1250
1251         /* Start the world */
1252 #ifdef CONFIG_X86_32
1253         i386_start_kernel();
1254 #else
1255         x86_64_start_reservations((char *)__pa_symbol(&boot_params));
1256 #endif
1257 }
1258
1259 static uint32_t xen_cpuid_base(void)
1260 {
1261         uint32_t base, eax, ebx, ecx, edx;
1262         char signature[13];
1263
1264         for (base = 0x40000000; base < 0x40010000; base += 0x100) {
1265                 cpuid(base, &eax, &ebx, &ecx, &edx);
1266                 *(uint32_t *)(signature + 0) = ebx;
1267                 *(uint32_t *)(signature + 4) = ecx;
1268                 *(uint32_t *)(signature + 8) = edx;
1269                 signature[12] = 0;
1270
1271                 if (!strcmp("XenVMMXenVMM", signature) && ((eax - base) >= 2))
1272                         return base;
1273         }
1274
1275         return 0;
1276 }
1277
1278 static int init_hvm_pv_info(int *major, int *minor)
1279 {
1280         uint32_t eax, ebx, ecx, edx, pages, msr, base;
1281         u64 pfn;
1282
1283         base = xen_cpuid_base();
1284         cpuid(base + 1, &eax, &ebx, &ecx, &edx);
1285
1286         *major = eax >> 16;
1287         *minor = eax & 0xffff;
1288         printk(KERN_INFO "Xen version %d.%d.\n", *major, *minor);
1289
1290         cpuid(base + 2, &pages, &msr, &ecx, &edx);
1291
1292         pfn = __pa(hypercall_page);
1293         wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
1294
1295         xen_setup_features();
1296
1297         pv_info = xen_info;
1298         pv_info.kernel_rpl = 0;
1299
1300         xen_domain_type = XEN_HVM_DOMAIN;
1301
1302         return 0;
1303 }
1304
1305 void xen_hvm_init_shared_info(void)
1306 {
1307         int cpu;
1308         struct xen_add_to_physmap xatp;
1309         static struct shared_info *shared_info_page = 0;
1310
1311         if (!shared_info_page)
1312                 shared_info_page = (struct shared_info *)
1313                         extend_brk(PAGE_SIZE, PAGE_SIZE);
1314         xatp.domid = DOMID_SELF;
1315         xatp.idx = 0;
1316         xatp.space = XENMAPSPACE_shared_info;
1317         xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
1318         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
1319                 BUG();
1320
1321         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
1322
1323         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1324          * page, we use it in the event channel upcall and in some pvclock
1325          * related functions. We don't need the vcpu_info placement
1326          * optimizations because we don't use any pv_mmu or pv_irq op on
1327          * HVM.
1328          * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1329          * online but xen_hvm_init_shared_info is run at resume time too and
1330          * in that case multiple vcpus might be online. */
1331         for_each_online_cpu(cpu) {
1332                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1333         }
1334 }
1335
1336 #ifdef CONFIG_XEN_PVHVM
1337 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
1338                                     unsigned long action, void *hcpu)
1339 {
1340         int cpu = (long)hcpu;
1341         switch (action) {
1342         case CPU_UP_PREPARE:
1343                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1344                 break;
1345         default:
1346                 break;
1347         }
1348         return NOTIFY_OK;
1349 }
1350
1351 static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier = {
1352         .notifier_call  = xen_hvm_cpu_notify,
1353 };
1354
1355 static void __init xen_hvm_guest_init(void)
1356 {
1357         int r;
1358         int major, minor;
1359
1360         r = init_hvm_pv_info(&major, &minor);
1361         if (r < 0)
1362                 return;
1363
1364         xen_hvm_init_shared_info();
1365
1366         if (xen_feature(XENFEAT_hvm_callback_vector))
1367                 xen_have_vector_callback = 1;
1368         register_cpu_notifier(&xen_hvm_cpu_notifier);
1369         xen_unplug_emulated_devices();
1370         have_vcpu_info_placement = 0;
1371         x86_init.irqs.intr_init = xen_init_IRQ;
1372         xen_hvm_init_time_ops();
1373         xen_hvm_init_mmu_ops();
1374 }
1375
1376 static bool __init xen_hvm_platform(void)
1377 {
1378         if (xen_pv_domain())
1379                 return false;
1380
1381         if (!xen_cpuid_base())
1382                 return false;
1383
1384         return true;
1385 }
1386
1387 const __refconst struct hypervisor_x86 x86_hyper_xen_hvm = {
1388         .name                   = "Xen HVM",
1389         .detect                 = xen_hvm_platform,
1390         .init_platform          = xen_hvm_guest_init,
1391 };
1392 EXPORT_SYMBOL(x86_hyper_xen_hvm);
1393 #endif