err.no Git - linux-2.6/blob - arch/i386/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/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/smp.h>
  17 #include <linux/preempt.h>
  18 #include <linux/percpu.h>
  19 #include <linux/delay.h>
  20 #include <linux/start_kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/bootmem.h>
  23 #include <linux/module.h>
  24
  25 #include <xen/interface/xen.h>
  26 #include <xen/interface/physdev.h>
  27 #include <xen/interface/vcpu.h>
  28 #include <xen/features.h>
  29 #include <xen/page.h>
  30
  31 #include <asm/paravirt.h>
  32 #include <asm/page.h>
  33 #include <asm/xen/hypercall.h>
  34 #include <asm/xen/hypervisor.h>
  35 #include <asm/fixmap.h>
  36 #include <asm/processor.h>
  37 #include <asm/setup.h>
  38 #include <asm/desc.h>
  39 #include <asm/pgtable.h>
  40
  41 #include "xen-ops.h"
  42 #include "mmu.h"
  43 #include "multicalls.h"
  44
  45 EXPORT_SYMBOL_GPL(hypercall_page);
  46
  47 DEFINE_PER_CPU(enum paravirt_lazy_mode, xen_lazy_mode);
  48
  49 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
  50 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
  51 DEFINE_PER_CPU(unsigned long, xen_cr3);
  52
  53 struct start_info *xen_start_info;
  54 EXPORT_SYMBOL_GPL(xen_start_info);
  55
  56 static void xen_vcpu_setup(int cpu)
  57 {
  58         per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
  59 }
  60
  61 static void __init xen_banner(void)
  62 {
  63         printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
  64                paravirt_ops.name);
  65         printk(KERN_INFO "Hypervisor signature: %s\n", xen_start_info->magic);
  66 }
  67
  68 static void xen_cpuid(unsigned int *eax, unsigned int *ebx,
  69                       unsigned int *ecx, unsigned int *edx)
  70 {
  71         unsigned maskedx = ~0;
  72
  73         /*
  74          * Mask out inconvenient features, to try and disable as many
  75          * unsupported kernel subsystems as possible.
  76          */
  77         if (*eax == 1)
  78                 maskedx = ~((1 << X86_FEATURE_APIC) |  /* disable APIC */
  79                             (1 << X86_FEATURE_ACPI) |  /* disable ACPI */
  80                             (1 << X86_FEATURE_ACC));   /* thermal monitoring */
  81
  82         asm(XEN_EMULATE_PREFIX "cpuid"
  83                 : "=a" (*eax),
  84                   "=b" (*ebx),
  85                   "=c" (*ecx),
  86                   "=d" (*edx)
  87                 : "0" (*eax), "2" (*ecx));
  88         *edx &= maskedx;
  89 }
  90
  91 static void xen_set_debugreg(int reg, unsigned long val)
  92 {
  93         HYPERVISOR_set_debugreg(reg, val);
  94 }
  95
  96 static unsigned long xen_get_debugreg(int reg)
  97 {
  98         return HYPERVISOR_get_debugreg(reg);
  99 }
 100
 101 static unsigned long xen_save_fl(void)
 102 {
 103         struct vcpu_info *vcpu;
 104         unsigned long flags;
 105
 106         preempt_disable();
 107         vcpu = x86_read_percpu(xen_vcpu);
 108         /* flag has opposite sense of mask */
 109         flags = !vcpu->evtchn_upcall_mask;
 110         preempt_enable();
 111
 112         /* convert to IF type flag
 113            -0 -> 0x00000000
 114            -1 -> 0xffffffff
 115         */
 116         return (-flags) & X86_EFLAGS_IF;
 117 }
 118
 119 static void xen_restore_fl(unsigned long flags)
 120 {
 121         struct vcpu_info *vcpu;
 122
 123         preempt_disable();
 124
 125         /* convert from IF type flag */
 126         flags = !(flags & X86_EFLAGS_IF);
 127         vcpu = x86_read_percpu(xen_vcpu);
 128         vcpu->evtchn_upcall_mask = flags;
 129
 130         if (flags == 0) {
 131                 /* Unmask then check (avoid races).  We're only protecting
 132                    against updates by this CPU, so there's no need for
 133                    anything stronger. */
 134                 barrier();
 135
 136                 if (unlikely(vcpu->evtchn_upcall_pending))
 137                         force_evtchn_callback();
 138                 preempt_enable();
 139         } else
 140                 preempt_enable_no_resched();
 141 }
 142
 143 static void xen_irq_disable(void)
 144 {
 145         struct vcpu_info *vcpu;
 146         preempt_disable();
 147         vcpu = x86_read_percpu(xen_vcpu);
 148         vcpu->evtchn_upcall_mask = 1;
 149         preempt_enable_no_resched();
 150 }
 151
 152 static void xen_irq_enable(void)
 153 {
 154         struct vcpu_info *vcpu;
 155
 156         preempt_disable();
 157         vcpu = x86_read_percpu(xen_vcpu);
 158         vcpu->evtchn_upcall_mask = 0;
 159
 160         /* Unmask then check (avoid races).  We're only protecting
 161            against updates by this CPU, so there's no need for
 162            anything stronger. */
 163         barrier();
 164
 165         if (unlikely(vcpu->evtchn_upcall_pending))
 166                 force_evtchn_callback();
 167         preempt_enable();
 168 }
 169
 170 static void xen_safe_halt(void)
 171 {
 172         /* Blocking includes an implicit local_irq_enable(). */
 173         if (HYPERVISOR_sched_op(SCHEDOP_block, 0) != 0)
 174                 BUG();
 175 }
 176
 177 static void xen_halt(void)
 178 {
 179         if (irqs_disabled())
 180                 HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
 181         else
 182                 xen_safe_halt();
 183 }
 184
 185 static void xen_set_lazy_mode(enum paravirt_lazy_mode mode)
 186 {
 187         switch (mode) {
 188         case PARAVIRT_LAZY_NONE:
 189                 BUG_ON(x86_read_percpu(xen_lazy_mode) == PARAVIRT_LAZY_NONE);
 190                 break;
 191
 192         case PARAVIRT_LAZY_MMU:
 193         case PARAVIRT_LAZY_CPU:
 194                 BUG_ON(x86_read_percpu(xen_lazy_mode) != PARAVIRT_LAZY_NONE);
 195                 break;
 196
 197         case PARAVIRT_LAZY_FLUSH:
 198                 /* flush if necessary, but don't change state */
 199                 if (x86_read_percpu(xen_lazy_mode) != PARAVIRT_LAZY_NONE)
 200                         xen_mc_flush();
 201                 return;
 202         }
 203
 204         xen_mc_flush();
 205         x86_write_percpu(xen_lazy_mode, mode);
 206 }
 207
 208 static unsigned long xen_store_tr(void)
 209 {
 210         return 0;
 211 }
 212
 213 static void xen_set_ldt(const void *addr, unsigned entries)
 214 {
 215         unsigned long linear_addr = (unsigned long)addr;
 216         struct mmuext_op *op;
 217         struct multicall_space mcs = xen_mc_entry(sizeof(*op));
 218
 219         op = mcs.args;
 220         op->cmd = MMUEXT_SET_LDT;
 221         if (linear_addr) {
 222                 /* ldt my be vmalloced, use arbitrary_virt_to_machine */
 223                 xmaddr_t maddr;
 224                 maddr = arbitrary_virt_to_machine((unsigned long)addr);
 225                 linear_addr = (unsigned long)maddr.maddr;
 226         }
 227         op->arg1.linear_addr = linear_addr;
 228         op->arg2.nr_ents = entries;
 229
 230         MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
 231
 232         xen_mc_issue(PARAVIRT_LAZY_CPU);
 233 }
 234
 235 static void xen_load_gdt(const struct Xgt_desc_struct *dtr)
 236 {
 237         unsigned long *frames;
 238         unsigned long va = dtr->address;
 239         unsigned int size = dtr->size + 1;
 240         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 241         int f;
 242         struct multicall_space mcs;
 243
 244         /* A GDT can be up to 64k in size, which corresponds to 8192
 245            8-byte entries, or 16 4k pages.. */
 246
 247         BUG_ON(size > 65536);
 248         BUG_ON(va & ~PAGE_MASK);
 249
 250         mcs = xen_mc_entry(sizeof(*frames) * pages);
 251         frames = mcs.args;
 252
 253         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
 254                 frames[f] = virt_to_mfn(va);
 255                 make_lowmem_page_readonly((void *)va);
 256         }
 257
 258         MULTI_set_gdt(mcs.mc, frames, size / sizeof(struct desc_struct));
 259
 260         xen_mc_issue(PARAVIRT_LAZY_CPU);
 261 }
 262
 263 static void load_TLS_descriptor(struct thread_struct *t,
 264                                 unsigned int cpu, unsigned int i)
 265 {
 266         struct desc_struct *gdt = get_cpu_gdt_table(cpu);
 267         xmaddr_t maddr = virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
 268         struct multicall_space mc = __xen_mc_entry(0);
 269
 270         MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
 271 }
 272
 273 static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
 274 {
 275         xen_mc_batch();
 276
 277         load_TLS_descriptor(t, cpu, 0);
 278         load_TLS_descriptor(t, cpu, 1);
 279         load_TLS_descriptor(t, cpu, 2);
 280
 281         xen_mc_issue(PARAVIRT_LAZY_CPU);
 282 }
 283
 284 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
 285                                 u32 low, u32 high)
 286 {
 287         unsigned long lp = (unsigned long)&dt[entrynum];
 288         xmaddr_t mach_lp = virt_to_machine(lp);
 289         u64 entry = (u64)high << 32 | low;
 290
 291         xen_mc_flush();
 292         if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
 293                 BUG();
 294 }
 295
 296 static int cvt_gate_to_trap(int vector, u32 low, u32 high,
 297                             struct trap_info *info)
 298 {
 299         u8 type, dpl;
 300
 301         type = (high >> 8) & 0x1f;
 302         dpl = (high >> 13) & 3;
 303
 304         if (type != 0xf && type != 0xe)
 305                 return 0;
 306
 307         info->vector = vector;
 308         info->address = (high & 0xffff0000) | (low & 0x0000ffff);
 309         info->cs = low >> 16;
 310         info->flags = dpl;
 311         /* interrupt gates clear IF */
 312         if (type == 0xe)
 313                 info->flags |= 4;
 314
 315         return 1;
 316 }
 317
 318 /* Locations of each CPU's IDT */
 319 static DEFINE_PER_CPU(struct Xgt_desc_struct, idt_desc);
 320
 321 /* Set an IDT entry.  If the entry is part of the current IDT, then
 322    also update Xen. */
 323 static void xen_write_idt_entry(struct desc_struct *dt, int entrynum,
 324                                 u32 low, u32 high)
 325 {
 326
 327         int cpu = smp_processor_id();
 328         unsigned long p = (unsigned long)&dt[entrynum];
 329         unsigned long start = per_cpu(idt_desc, cpu).address;
 330         unsigned long end = start + per_cpu(idt_desc, cpu).size + 1;
 331
 332         xen_mc_flush();
 333
 334         write_dt_entry(dt, entrynum, low, high);
 335
 336         if (p >= start && (p + 8) <= end) {
 337                 struct trap_info info[2];
 338
 339                 info[1].address = 0;
 340
 341                 if (cvt_gate_to_trap(entrynum, low, high, &info[0]))
 342                         if (HYPERVISOR_set_trap_table(info))
 343                                 BUG();
 344         }
 345 }
 346
 347 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
 348    hold a spinlock to protect the static traps[] array (static because
 349    it avoids allocation, and saves stack space). */
 350 static void xen_load_idt(const struct Xgt_desc_struct *desc)
 351 {
 352         static DEFINE_SPINLOCK(lock);
 353         static struct trap_info traps[257];
 354
 355         int cpu = smp_processor_id();
 356         unsigned in, out, count;
 357
 358         per_cpu(idt_desc, cpu) = *desc;
 359
 360         count = (desc->size+1) / 8;
 361         BUG_ON(count > 256);
 362
 363         spin_lock(&lock);
 364         for (in = out = 0; in < count; in++) {
 365                 const u32 *entry = (u32 *)(desc->address + in * 8);
 366
 367                 if (cvt_gate_to_trap(in, entry[0], entry[1], &traps[out]))
 368                         out++;
 369         }
 370         traps[out].address = 0;
 371
 372         xen_mc_flush();
 373         if (HYPERVISOR_set_trap_table(traps))
 374                 BUG();
 375
 376         spin_unlock(&lock);
 377 }
 378
 379 /* Write a GDT descriptor entry.  Ignore LDT descriptors, since
 380    they're handled differently. */
 381 static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
 382                                 u32 low, u32 high)
 383 {
 384         switch ((high >> 8) & 0xff) {
 385         case DESCTYPE_LDT:
 386         case DESCTYPE_TSS:
 387                 /* ignore */
 388                 break;
 389
 390         default: {
 391                 xmaddr_t maddr = virt_to_machine(&dt[entry]);
 392                 u64 desc = (u64)high << 32 | low;
 393
 394                 xen_mc_flush();
 395                 if (HYPERVISOR_update_descriptor(maddr.maddr, desc))
 396                         BUG();
 397         }
 398
 399         }
 400 }
 401
 402 static void xen_load_esp0(struct tss_struct *tss,
 403                                    struct thread_struct *thread)
 404 {
 405         struct multicall_space mcs = xen_mc_entry(0);
 406         MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->esp0);
 407         xen_mc_issue(PARAVIRT_LAZY_CPU);
 408 }
 409
 410 static void xen_set_iopl_mask(unsigned mask)
 411 {
 412         struct physdev_set_iopl set_iopl;
 413
 414         /* Force the change at ring 0. */
 415         set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
 416         HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
 417 }
 418
 419 static void xen_io_delay(void)
 420 {
 421 }
 422
 423 #ifdef CONFIG_X86_LOCAL_APIC
 424 static unsigned long xen_apic_read(unsigned long reg)
 425 {
 426         return 0;
 427 }
 428 #endif
 429
 430 static void xen_flush_tlb(void)
 431 {
 432         struct mmuext_op op;
 433
 434         op.cmd = MMUEXT_TLB_FLUSH_LOCAL;
 435         if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
 436                 BUG();
 437 }
 438
 439 static void xen_flush_tlb_single(unsigned long addr)
 440 {
 441         struct mmuext_op op;
 442
 443         op.cmd = MMUEXT_INVLPG_LOCAL;
 444         op.arg1.linear_addr = addr & PAGE_MASK;
 445         if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
 446                 BUG();
 447 }
 448
 449 static unsigned long xen_read_cr2(void)
 450 {
 451         return x86_read_percpu(xen_vcpu)->arch.cr2;
 452 }
 453
 454 static void xen_write_cr4(unsigned long cr4)
 455 {
 456         /* never allow TSC to be disabled */
 457         native_write_cr4(cr4 & ~X86_CR4_TSD);
 458 }
 459
 460 /*
 461  * Page-directory addresses above 4GB do not fit into architectural %cr3.
 462  * When accessing %cr3, or equivalent field in vcpu_guest_context, guests
 463  * must use the following accessor macros to pack/unpack valid MFNs.
 464  *
 465  * Note that Xen is using the fact that the pagetable base is always
 466  * page-aligned, and putting the 12 MSB of the address into the 12 LSB
 467  * of cr3.
 468  */
 469 #define xen_pfn_to_cr3(pfn) (((unsigned)(pfn) << 12) | ((unsigned)(pfn) >> 20))
 470 #define xen_cr3_to_pfn(cr3) (((unsigned)(cr3) >> 12) | ((unsigned)(cr3) << 20))
 471
 472 static unsigned long xen_read_cr3(void)
 473 {
 474         return x86_read_percpu(xen_cr3);
 475 }
 476
 477 static void xen_write_cr3(unsigned long cr3)
 478 {
 479         if (cr3 == x86_read_percpu(xen_cr3)) {
 480                 /* just a simple tlb flush */
 481                 xen_flush_tlb();
 482                 return;
 483         }
 484
 485         x86_write_percpu(xen_cr3, cr3);
 486
 487
 488         {
 489                 struct mmuext_op *op;
 490                 struct multicall_space mcs = xen_mc_entry(sizeof(*op));
 491                 unsigned long mfn = pfn_to_mfn(PFN_DOWN(cr3));
 492
 493                 op = mcs.args;
 494                 op->cmd = MMUEXT_NEW_BASEPTR;
 495                 op->arg1.mfn = mfn;
 496
 497                 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
 498
 499                 xen_mc_issue(PARAVIRT_LAZY_CPU);
 500         }
 501 }
 502
 503 static void xen_alloc_pt(struct mm_struct *mm, u32 pfn)
 504 {
 505         /* XXX pfn isn't necessarily a lowmem page */
 506         make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
 507 }
 508
 509 static void xen_alloc_pd(u32 pfn)
 510 {
 511         make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
 512 }
 513
 514 static void xen_release_pd(u32 pfn)
 515 {
 516         make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
 517 }
 518
 519 static void xen_release_pt(u32 pfn)
 520 {
 521         make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
 522 }
 523
 524 static void xen_alloc_pd_clone(u32 pfn, u32 clonepfn,
 525                                         u32 start, u32 count)
 526 {
 527         xen_alloc_pd(pfn);
 528 }
 529
 530 static __init void xen_pagetable_setup_start(pgd_t *base)
 531 {
 532         pgd_t *xen_pgd = (pgd_t *)xen_start_info->pt_base;
 533
 534         init_mm.pgd = base;
 535         /*
 536          * copy top-level of Xen-supplied pagetable into place.  For
 537          * !PAE we can use this as-is, but for PAE it is a stand-in
 538          * while we copy the pmd pages.
 539          */
 540         memcpy(base, xen_pgd, PTRS_PER_PGD * sizeof(pgd_t));
 541
 542         if (PTRS_PER_PMD > 1) {
 543                 int i;
 544                 /*
 545                  * For PAE, need to allocate new pmds, rather than
 546                  * share Xen's, since Xen doesn't like pmd's being
 547                  * shared between address spaces.
 548                  */
 549                 for (i = 0; i < PTRS_PER_PGD; i++) {
 550                         if (pgd_val_ma(xen_pgd[i]) & _PAGE_PRESENT) {
 551                                 pmd_t *pmd = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
 552
 553                                 memcpy(pmd, (void *)pgd_page_vaddr(xen_pgd[i]),
 554                                        PAGE_SIZE);
 555
 556                                 xen_alloc_pd(PFN_DOWN(__pa(pmd)));
 557
 558                                 set_pgd(&base[i], __pgd(1 + __pa(pmd)));
 559                         } else
 560                                 pgd_clear(&base[i]);
 561                 }
 562         }
 563
 564         /* make sure zero_page is mapped RO so we can use it in pagetables */
 565         make_lowmem_page_readonly(empty_zero_page);
 566         make_lowmem_page_readonly(base);
 567         /*
 568          * Switch to new pagetable.  This is done before
 569          * pagetable_init has done anything so that the new pages
 570          * added to the table can be prepared properly for Xen.
 571          */
 572         xen_write_cr3(__pa(base));
 573 }
 574
 575 static __init void xen_pagetable_setup_done(pgd_t *base)
 576 {
 577         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 578                 /*
 579                  * Create a mapping for the shared info page.
 580                  * Should be set_fixmap(), but shared_info is a machine
 581                  * address with no corresponding pseudo-phys address.
 582                  */
 583                 set_pte_mfn(fix_to_virt(FIX_PARAVIRT_BOOTMAP),
 584                             PFN_DOWN(xen_start_info->shared_info),
 585                             PAGE_KERNEL);
 586
 587                 HYPERVISOR_shared_info =
 588                         (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
 589
 590         } else
 591                 HYPERVISOR_shared_info =
 592                         (struct shared_info *)__va(xen_start_info->shared_info);
 593
 594         xen_pgd_pin(base);
 595
 596         xen_vcpu_setup(smp_processor_id());
 597 }
 598
 599 static const struct paravirt_ops xen_paravirt_ops __initdata = {
 600         .paravirt_enabled = 1,
 601         .shared_kernel_pmd = 0,
 602
 603         .name = "Xen",
 604         .banner = xen_banner,
 605
 606         .patch = paravirt_patch_default,
 607
 608         .memory_setup = xen_memory_setup,
 609         .arch_setup = xen_arch_setup,
 610         .init_IRQ = xen_init_IRQ,
 611
 612         .cpuid = xen_cpuid,
 613
 614         .set_debugreg = xen_set_debugreg,
 615         .get_debugreg = xen_get_debugreg,
 616
 617         .clts = native_clts,
 618
 619         .read_cr0 = native_read_cr0,
 620         .write_cr0 = native_write_cr0,
 621
 622         .read_cr2 = xen_read_cr2,
 623         .write_cr2 = native_write_cr2,
 624
 625         .read_cr3 = xen_read_cr3,
 626         .write_cr3 = xen_write_cr3,
 627
 628         .read_cr4 = native_read_cr4,
 629         .read_cr4_safe = native_read_cr4_safe,
 630         .write_cr4 = xen_write_cr4,
 631
 632         .save_fl = xen_save_fl,
 633         .restore_fl = xen_restore_fl,
 634         .irq_disable = xen_irq_disable,
 635         .irq_enable = xen_irq_enable,
 636         .safe_halt = xen_safe_halt,
 637         .halt = xen_halt,
 638         .wbinvd = native_wbinvd,
 639
 640         .read_msr = native_read_msr_safe,
 641         .write_msr = native_write_msr_safe,
 642         .read_tsc = native_read_tsc,
 643         .read_pmc = native_read_pmc,
 644
 645         .iret = (void *)&hypercall_page[__HYPERVISOR_iret],
 646         .irq_enable_sysexit = NULL,  /* never called */
 647
 648         .load_tr_desc = paravirt_nop,
 649         .set_ldt = xen_set_ldt,
 650         .load_gdt = xen_load_gdt,
 651         .load_idt = xen_load_idt,
 652         .load_tls = xen_load_tls,
 653
 654         .store_gdt = native_store_gdt,
 655         .store_idt = native_store_idt,
 656         .store_tr = xen_store_tr,
 657
 658         .write_ldt_entry = xen_write_ldt_entry,
 659         .write_gdt_entry = xen_write_gdt_entry,
 660         .write_idt_entry = xen_write_idt_entry,
 661         .load_esp0 = xen_load_esp0,
 662
 663         .set_iopl_mask = xen_set_iopl_mask,
 664         .io_delay = xen_io_delay,
 665
 666 #ifdef CONFIG_X86_LOCAL_APIC
 667         .apic_write = paravirt_nop,
 668         .apic_write_atomic = paravirt_nop,
 669         .apic_read = xen_apic_read,
 670         .setup_boot_clock = paravirt_nop,
 671         .setup_secondary_clock = paravirt_nop,
 672         .startup_ipi_hook = paravirt_nop,
 673 #endif
 674
 675         .flush_tlb_user = xen_flush_tlb,
 676         .flush_tlb_kernel = xen_flush_tlb,
 677         .flush_tlb_single = xen_flush_tlb_single,
 678
 679         .pte_update = paravirt_nop,
 680         .pte_update_defer = paravirt_nop,
 681
 682         .pagetable_setup_start = xen_pagetable_setup_start,
 683         .pagetable_setup_done = xen_pagetable_setup_done,
 684
 685         .alloc_pt = xen_alloc_pt,
 686         .alloc_pd = xen_alloc_pd,
 687         .alloc_pd_clone = xen_alloc_pd_clone,
 688         .release_pd = xen_release_pd,
 689         .release_pt = xen_release_pt,
 690
 691         .set_pte = xen_set_pte,
 692         .set_pte_at = xen_set_pte_at,
 693         .set_pmd = xen_set_pmd,
 694
 695         .pte_val = xen_pte_val,
 696         .pgd_val = xen_pgd_val,
 697
 698         .make_pte = xen_make_pte,
 699         .make_pgd = xen_make_pgd,
 700
 701 #ifdef CONFIG_X86_PAE
 702         .set_pte_atomic = xen_set_pte_atomic,
 703         .set_pte_present = xen_set_pte_at,
 704         .set_pud = xen_set_pud,
 705         .pte_clear = xen_pte_clear,
 706         .pmd_clear = xen_pmd_clear,
 707
 708         .make_pmd = xen_make_pmd,
 709         .pmd_val = xen_pmd_val,
 710 #endif  /* PAE */
 711
 712         .activate_mm = xen_activate_mm,
 713         .dup_mmap = xen_dup_mmap,
 714         .exit_mmap = xen_exit_mmap,
 715
 716         .set_lazy_mode = xen_set_lazy_mode,
 717 };
 718
 719 /* First C function to be called on Xen boot */
 720 asmlinkage void __init xen_start_kernel(void)
 721 {
 722         pgd_t *pgd;
 723
 724         if (!xen_start_info)
 725                 return;
 726
 727         BUG_ON(memcmp(xen_start_info->magic, "xen-3.0", 7) != 0);
 728
 729         /* Install Xen paravirt ops */
 730         paravirt_ops = xen_paravirt_ops;
 731
 732         xen_setup_features();
 733
 734         /* Get mfn list */
 735         if (!xen_feature(XENFEAT_auto_translated_physmap))
 736                 phys_to_machine_mapping = (unsigned long *)xen_start_info->mfn_list;
 737
 738         pgd = (pgd_t *)xen_start_info->pt_base;
 739
 740         init_pg_tables_end = __pa(pgd) + xen_start_info->nr_pt_frames*PAGE_SIZE;
 741
 742         init_mm.pgd = pgd; /* use the Xen pagetables to start */
 743
 744         /* keep using Xen gdt for now; no urgent need to change it */
 745
 746         x86_write_percpu(xen_cr3, __pa(pgd));
 747         xen_vcpu_setup(0);
 748
 749         paravirt_ops.kernel_rpl = 1;
 750         if (xen_feature(XENFEAT_supervisor_mode_kernel))
 751                 paravirt_ops.kernel_rpl = 0;
 752
 753         /* set the limit of our address space */
 754         reserve_top_address(-HYPERVISOR_VIRT_START + 2 * PAGE_SIZE);
 755
 756         /* set up basic CPUID stuff */
 757         cpu_detect(&new_cpu_data);
 758         new_cpu_data.hard_math = 1;
 759         new_cpu_data.x86_capability[0] = cpuid_edx(1);
 760
 761         /* Poke various useful things into boot_params */
 762         LOADER_TYPE = (9 << 4) | 0;
 763         INITRD_START = xen_start_info->mod_start ? __pa(xen_start_info->mod_start) : 0;
 764         INITRD_SIZE = xen_start_info->mod_len;
 765
 766         /* Start the world */
 767         start_kernel();
 768 }