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/events.h> 37 #include <xen/interface/xen.h> 38 #include <xen/interface/version.h> 39 #include <xen/interface/physdev.h> 40 #include <xen/interface/vcpu.h> 41 #include <xen/interface/memory.h> 42 #include <xen/interface/xen-mca.h> 43 #include <xen/features.h> 44 #include <xen/page.h> 45 #include <xen/hvm.h> 46 #include <xen/hvc-console.h> 47 #include <xen/acpi.h> 48 49 #include <asm/paravirt.h> 50 #include <asm/apic.h> 51 #include <asm/page.h> 52 #include <asm/xen/pci.h> 53 #include <asm/xen/hypercall.h> 54 #include <asm/xen/hypervisor.h> 55 #include <asm/fixmap.h> 56 #include <asm/processor.h> 57 #include <asm/proto.h> 58 #include <asm/msr-index.h> 59 #include <asm/traps.h> 60 #include <asm/setup.h> 61 #include <asm/desc.h> 62 #include <asm/pgalloc.h> 63 #include <asm/pgtable.h> 64 #include <asm/tlbflush.h> 65 #include <asm/reboot.h> 66 #include <asm/stackprotector.h> 67 #include <asm/hypervisor.h> 68 #include <asm/mwait.h> 69 #include <asm/pci_x86.h> 70 71 #ifdef CONFIG_ACPI 72 #include <linux/acpi.h> 73 #include <asm/acpi.h> 74 #include <acpi/pdc_intel.h> 75 #include <acpi/processor.h> 76 #include <xen/interface/platform.h> 77 #endif 78 79 #include "xen-ops.h" 80 #include "mmu.h" 81 #include "smp.h" 82 #include "multicalls.h" 83 84 EXPORT_SYMBOL_GPL(hypercall_page); 85 86 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); 87 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info); 88 89 enum xen_domain_type xen_domain_type = XEN_NATIVE; 90 EXPORT_SYMBOL_GPL(xen_domain_type); 91 92 unsigned long *machine_to_phys_mapping = (void *)MACH2PHYS_VIRT_START; 93 EXPORT_SYMBOL(machine_to_phys_mapping); 94 unsigned long machine_to_phys_nr; 95 EXPORT_SYMBOL(machine_to_phys_nr); 96 97 struct start_info *xen_start_info; 98 EXPORT_SYMBOL_GPL(xen_start_info); 99 100 struct shared_info xen_dummy_shared_info; 101 102 void *xen_initial_gdt; 103 104 RESERVE_BRK(shared_info_page_brk, PAGE_SIZE); 105 __read_mostly int xen_have_vector_callback; 106 EXPORT_SYMBOL_GPL(xen_have_vector_callback); 107 108 /* 109 * Point at some empty memory to start with. We map the real shared_info 110 * page as soon as fixmap is up and running. 111 */ 112 struct shared_info *HYPERVISOR_shared_info = &xen_dummy_shared_info; 113 114 /* 115 * Flag to determine whether vcpu info placement is available on all 116 * VCPUs. We assume it is to start with, and then set it to zero on 117 * the first failure. This is because it can succeed on some VCPUs 118 * and not others, since it can involve hypervisor memory allocation, 119 * or because the guest failed to guarantee all the appropriate 120 * constraints on all VCPUs (ie buffer can't cross a page boundary). 121 * 122 * Note that any particular CPU may be using a placed vcpu structure, 123 * but we can only optimise if the all are. 124 * 125 * 0: not available, 1: available 126 */ 127 static int have_vcpu_info_placement = 1; 128 129 struct tls_descs { 130 struct desc_struct desc[3]; 131 }; 132 133 /* 134 * Updating the 3 TLS descriptors in the GDT on every task switch is 135 * surprisingly expensive so we avoid updating them if they haven't 136 * changed. Since Xen writes different descriptors than the one 137 * passed in the update_descriptor hypercall we keep shadow copies to 138 * compare against. 139 */ 140 static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc); 141 142 static void clamp_max_cpus(void) 143 { 144 #ifdef CONFIG_SMP 145 if (setup_max_cpus > MAX_VIRT_CPUS) 146 setup_max_cpus = MAX_VIRT_CPUS; 147 #endif 148 } 149 150 static void xen_vcpu_setup(int cpu) 151 { 152 struct vcpu_register_vcpu_info info; 153 int err; 154 struct vcpu_info *vcpup; 155 156 BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info); 157 158 if (cpu < MAX_VIRT_CPUS) 159 per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; 160 161 if (!have_vcpu_info_placement) { 162 if (cpu >= MAX_VIRT_CPUS) 163 clamp_max_cpus(); 164 return; 165 } 166 167 vcpup = &per_cpu(xen_vcpu_info, cpu); 168 info.mfn = arbitrary_virt_to_mfn(vcpup); 169 info.offset = offset_in_page(vcpup); 170 171 /* Check to see if the hypervisor will put the vcpu_info 172 structure where we want it, which allows direct access via 173 a percpu-variable. */ 174 err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); 175 176 if (err) { 177 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err); 178 have_vcpu_info_placement = 0; 179 clamp_max_cpus(); 180 } else { 181 /* This cpu is using the registered vcpu info, even if 182 later ones fail to. */ 183 per_cpu(xen_vcpu, cpu) = vcpup; 184 } 185 } 186 187 /* 188 * On restore, set the vcpu placement up again. 189 * If it fails, then we're in a bad state, since 190 * we can't back out from using it... 191 */ 192 void xen_vcpu_restore(void) 193 { 194 int cpu; 195 196 for_each_possible_cpu(cpu) { 197 bool other_cpu = (cpu != smp_processor_id()); 198 bool is_up = HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL); 199 200 if (other_cpu && is_up && 201 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL)) 202 BUG(); 203 204 xen_setup_runstate_info(cpu); 205 206 if (have_vcpu_info_placement) 207 xen_vcpu_setup(cpu); 208 209 if (other_cpu && is_up && 210 HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL)) 211 BUG(); 212 } 213 } 214 215 static void __init xen_banner(void) 216 { 217 unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL); 218 struct xen_extraversion extra; 219 HYPERVISOR_xen_version(XENVER_extraversion, &extra); 220 221 printk(KERN_INFO "Booting paravirtualized kernel on %s\n", 222 pv_info.name); 223 printk(KERN_INFO "Xen version: %d.%d%s%s\n", 224 version >> 16, version & 0xffff, extra.extraversion, 225 xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); 226 } 227 /* Check if running on Xen version (major, minor) or later */ 228 bool 229 xen_running_on_version_or_later(unsigned int major, unsigned int minor) 230 { 231 unsigned int version; 232 233 if (!xen_domain()) 234 return false; 235 236 version = HYPERVISOR_xen_version(XENVER_version, NULL); 237 if ((((version >> 16) == major) && ((version & 0xffff) >= minor)) || 238 ((version >> 16) > major)) 239 return true; 240 return false; 241 } 242 243 #define CPUID_THERM_POWER_LEAF 6 244 #define APERFMPERF_PRESENT 0 245 246 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0; 247 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0; 248 249 static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask; 250 static __read_mostly unsigned int cpuid_leaf5_ecx_val; 251 static __read_mostly unsigned int cpuid_leaf5_edx_val; 252 253 static void xen_cpuid(unsigned int *ax, unsigned int *bx, 254 unsigned int *cx, unsigned int *dx) 255 { 256 unsigned maskebx = ~0; 257 unsigned maskecx = ~0; 258 unsigned maskedx = ~0; 259 unsigned setecx = 0; 260 /* 261 * Mask out inconvenient features, to try and disable as many 262 * unsupported kernel subsystems as possible. 263 */ 264 switch (*ax) { 265 case 1: 266 maskecx = cpuid_leaf1_ecx_mask; 267 setecx = cpuid_leaf1_ecx_set_mask; 268 maskedx = cpuid_leaf1_edx_mask; 269 break; 270 271 case CPUID_MWAIT_LEAF: 272 /* Synthesize the values.. */ 273 *ax = 0; 274 *bx = 0; 275 *cx = cpuid_leaf5_ecx_val; 276 *dx = cpuid_leaf5_edx_val; 277 return; 278 279 case CPUID_THERM_POWER_LEAF: 280 /* Disabling APERFMPERF for kernel usage */ 281 maskecx = ~(1 << APERFMPERF_PRESENT); 282 break; 283 284 case 0xb: 285 /* Suppress extended topology stuff */ 286 maskebx = 0; 287 break; 288 } 289 290 asm(XEN_EMULATE_PREFIX "cpuid" 291 : "=a" (*ax), 292 "=b" (*bx), 293 "=c" (*cx), 294 "=d" (*dx) 295 : "0" (*ax), "2" (*cx)); 296 297 *bx &= maskebx; 298 *cx &= maskecx; 299 *cx |= setecx; 300 *dx &= maskedx; 301 302 } 303 304 static bool __init xen_check_mwait(void) 305 { 306 #ifdef CONFIG_ACPI 307 struct xen_platform_op op = { 308 .cmd = XENPF_set_processor_pminfo, 309 .u.set_pminfo.id = -1, 310 .u.set_pminfo.type = XEN_PM_PDC, 311 }; 312 uint32_t buf[3]; 313 unsigned int ax, bx, cx, dx; 314 unsigned int mwait_mask; 315 316 /* We need to determine whether it is OK to expose the MWAIT 317 * capability to the kernel to harvest deeper than C3 states from ACPI 318 * _CST using the processor_harvest_xen.c module. For this to work, we 319 * need to gather the MWAIT_LEAF values (which the cstate.c code 320 * checks against). The hypervisor won't expose the MWAIT flag because 321 * it would break backwards compatibility; so we will find out directly 322 * from the hardware and hypercall. 323 */ 324 if (!xen_initial_domain()) 325 return false; 326 327 /* 328 * When running under platform earlier than Xen4.2, do not expose 329 * mwait, to avoid the risk of loading native acpi pad driver 330 */ 331 if (!xen_running_on_version_or_later(4, 2)) 332 return false; 333 334 ax = 1; 335 cx = 0; 336 337 native_cpuid(&ax, &bx, &cx, &dx); 338 339 mwait_mask = (1 << (X86_FEATURE_EST % 32)) | 340 (1 << (X86_FEATURE_MWAIT % 32)); 341 342 if ((cx & mwait_mask) != mwait_mask) 343 return false; 344 345 /* We need to emulate the MWAIT_LEAF and for that we need both 346 * ecx and edx. The hypercall provides only partial information. 347 */ 348 349 ax = CPUID_MWAIT_LEAF; 350 bx = 0; 351 cx = 0; 352 dx = 0; 353 354 native_cpuid(&ax, &bx, &cx, &dx); 355 356 /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so, 357 * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3. 358 */ 359 buf[0] = ACPI_PDC_REVISION_ID; 360 buf[1] = 1; 361 buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP); 362 363 set_xen_guest_handle(op.u.set_pminfo.pdc, buf); 364 365 if ((HYPERVISOR_dom0_op(&op) == 0) && 366 (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) { 367 cpuid_leaf5_ecx_val = cx; 368 cpuid_leaf5_edx_val = dx; 369 } 370 return true; 371 #else 372 return false; 373 #endif 374 } 375 static void __init xen_init_cpuid_mask(void) 376 { 377 unsigned int ax, bx, cx, dx; 378 unsigned int xsave_mask; 379 380 cpuid_leaf1_edx_mask = 381 ~((1 << X86_FEATURE_MTRR) | /* disable MTRR */ 382 (1 << X86_FEATURE_ACC)); /* thermal monitoring */ 383 384 if (!xen_initial_domain()) 385 cpuid_leaf1_edx_mask &= 386 ~((1 << X86_FEATURE_APIC) | /* disable local APIC */ 387 (1 << X86_FEATURE_ACPI)); /* disable ACPI */ 388 ax = 1; 389 cx = 0; 390 xen_cpuid(&ax, &bx, &cx, &dx); 391 392 xsave_mask = 393 (1 << (X86_FEATURE_XSAVE % 32)) | 394 (1 << (X86_FEATURE_OSXSAVE % 32)); 395 396 /* Xen will set CR4.OSXSAVE if supported and not disabled by force */ 397 if ((cx & xsave_mask) != xsave_mask) 398 cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */ 399 if (xen_check_mwait()) 400 cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32)); 401 } 402 403 static void xen_set_debugreg(int reg, unsigned long val) 404 { 405 HYPERVISOR_set_debugreg(reg, val); 406 } 407 408 static unsigned long xen_get_debugreg(int reg) 409 { 410 return HYPERVISOR_get_debugreg(reg); 411 } 412 413 static void xen_end_context_switch(struct task_struct *next) 414 { 415 xen_mc_flush(); 416 paravirt_end_context_switch(next); 417 } 418 419 static unsigned long xen_store_tr(void) 420 { 421 return 0; 422 } 423 424 /* 425 * Set the page permissions for a particular virtual address. If the 426 * address is a vmalloc mapping (or other non-linear mapping), then 427 * find the linear mapping of the page and also set its protections to 428 * match. 429 */ 430 static void set_aliased_prot(void *v, pgprot_t prot) 431 { 432 int level; 433 pte_t *ptep; 434 pte_t pte; 435 unsigned long pfn; 436 struct page *page; 437 438 ptep = lookup_address((unsigned long)v, &level); 439 BUG_ON(ptep == NULL); 440 441 pfn = pte_pfn(*ptep); 442 page = pfn_to_page(pfn); 443 444 pte = pfn_pte(pfn, prot); 445 446 if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0)) 447 BUG(); 448 449 if (!PageHighMem(page)) { 450 void *av = __va(PFN_PHYS(pfn)); 451 452 if (av != v) 453 if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0)) 454 BUG(); 455 } else 456 kmap_flush_unused(); 457 } 458 459 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries) 460 { 461 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; 462 int i; 463 464 for(i = 0; i < entries; i += entries_per_page) 465 set_aliased_prot(ldt + i, PAGE_KERNEL_RO); 466 } 467 468 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries) 469 { 470 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; 471 int i; 472 473 for(i = 0; i < entries; i += entries_per_page) 474 set_aliased_prot(ldt + i, PAGE_KERNEL); 475 } 476 477 static void xen_set_ldt(const void *addr, unsigned entries) 478 { 479 struct mmuext_op *op; 480 struct multicall_space mcs = xen_mc_entry(sizeof(*op)); 481 482 trace_xen_cpu_set_ldt(addr, entries); 483 484 op = mcs.args; 485 op->cmd = MMUEXT_SET_LDT; 486 op->arg1.linear_addr = (unsigned long)addr; 487 op->arg2.nr_ents = entries; 488 489 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); 490 491 xen_mc_issue(PARAVIRT_LAZY_CPU); 492 } 493 494 static void xen_load_gdt(const struct desc_ptr *dtr) 495 { 496 unsigned long va = dtr->address; 497 unsigned int size = dtr->size + 1; 498 unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE; 499 unsigned long frames[pages]; 500 int f; 501 502 /* 503 * A GDT can be up to 64k in size, which corresponds to 8192 504 * 8-byte entries, or 16 4k pages.. 505 */ 506 507 BUG_ON(size > 65536); 508 BUG_ON(va & ~PAGE_MASK); 509 510 for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { 511 int level; 512 pte_t *ptep; 513 unsigned long pfn, mfn; 514 void *virt; 515 516 /* 517 * The GDT is per-cpu and is in the percpu data area. 518 * That can be virtually mapped, so we need to do a 519 * page-walk to get the underlying MFN for the 520 * hypercall. The page can also be in the kernel's 521 * linear range, so we need to RO that mapping too. 522 */ 523 ptep = lookup_address(va, &level); 524 BUG_ON(ptep == NULL); 525 526 pfn = pte_pfn(*ptep); 527 mfn = pfn_to_mfn(pfn); 528 virt = __va(PFN_PHYS(pfn)); 529 530 frames[f] = mfn; 531 532 make_lowmem_page_readonly((void *)va); 533 make_lowmem_page_readonly(virt); 534 } 535 536 if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) 537 BUG(); 538 } 539 540 /* 541 * load_gdt for early boot, when the gdt is only mapped once 542 */ 543 static void __init xen_load_gdt_boot(const struct desc_ptr *dtr) 544 { 545 unsigned long va = dtr->address; 546 unsigned int size = dtr->size + 1; 547 unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE; 548 unsigned long frames[pages]; 549 int f; 550 551 /* 552 * A GDT can be up to 64k in size, which corresponds to 8192 553 * 8-byte entries, or 16 4k pages.. 554 */ 555 556 BUG_ON(size > 65536); 557 BUG_ON(va & ~PAGE_MASK); 558 559 for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { 560 pte_t pte; 561 unsigned long pfn, mfn; 562 563 pfn = virt_to_pfn(va); 564 mfn = pfn_to_mfn(pfn); 565 566 pte = pfn_pte(pfn, PAGE_KERNEL_RO); 567 568 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0)) 569 BUG(); 570 571 frames[f] = mfn; 572 } 573 574 if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) 575 BUG(); 576 } 577 578 static inline bool desc_equal(const struct desc_struct *d1, 579 const struct desc_struct *d2) 580 { 581 return d1->a == d2->a && d1->b == d2->b; 582 } 583 584 static void load_TLS_descriptor(struct thread_struct *t, 585 unsigned int cpu, unsigned int i) 586 { 587 struct desc_struct *shadow = &per_cpu(shadow_tls_desc, cpu).desc[i]; 588 struct desc_struct *gdt; 589 xmaddr_t maddr; 590 struct multicall_space mc; 591 592 if (desc_equal(shadow, &t->tls_array[i])) 593 return; 594 595 *shadow = t->tls_array[i]; 596 597 gdt = get_cpu_gdt_table(cpu); 598 maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]); 599 mc = __xen_mc_entry(0); 600 601 MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]); 602 } 603 604 static void xen_load_tls(struct thread_struct *t, unsigned int cpu) 605 { 606 /* 607 * XXX sleazy hack: If we're being called in a lazy-cpu zone 608 * and lazy gs handling is enabled, it means we're in a 609 * context switch, and %gs has just been saved. This means we 610 * can zero it out to prevent faults on exit from the 611 * hypervisor if the next process has no %gs. Either way, it 612 * has been saved, and the new value will get loaded properly. 613 * This will go away as soon as Xen has been modified to not 614 * save/restore %gs for normal hypercalls. 615 * 616 * On x86_64, this hack is not used for %gs, because gs points 617 * to KERNEL_GS_BASE (and uses it for PDA references), so we 618 * must not zero %gs on x86_64 619 * 620 * For x86_64, we need to zero %fs, otherwise we may get an 621 * exception between the new %fs descriptor being loaded and 622 * %fs being effectively cleared at __switch_to(). 623 */ 624 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { 625 #ifdef CONFIG_X86_32 626 lazy_load_gs(0); 627 #else 628 loadsegment(fs, 0); 629 #endif 630 } 631 632 xen_mc_batch(); 633 634 load_TLS_descriptor(t, cpu, 0); 635 load_TLS_descriptor(t, cpu, 1); 636 load_TLS_descriptor(t, cpu, 2); 637 638 xen_mc_issue(PARAVIRT_LAZY_CPU); 639 } 640 641 #ifdef CONFIG_X86_64 642 static void xen_load_gs_index(unsigned int idx) 643 { 644 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx)) 645 BUG(); 646 } 647 #endif 648 649 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, 650 const void *ptr) 651 { 652 xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]); 653 u64 entry = *(u64 *)ptr; 654 655 trace_xen_cpu_write_ldt_entry(dt, entrynum, entry); 656 657 preempt_disable(); 658 659 xen_mc_flush(); 660 if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry)) 661 BUG(); 662 663 preempt_enable(); 664 } 665 666 static int cvt_gate_to_trap(int vector, const gate_desc *val, 667 struct trap_info *info) 668 { 669 unsigned long addr; 670 671 if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT) 672 return 0; 673 674 info->vector = vector; 675 676 addr = gate_offset(*val); 677 #ifdef CONFIG_X86_64 678 /* 679 * Look for known traps using IST, and substitute them 680 * appropriately. The debugger ones are the only ones we care 681 * about. Xen will handle faults like double_fault, 682 * so we should never see them. Warn if 683 * there's an unexpected IST-using fault handler. 684 */ 685 if (addr == (unsigned long)debug) 686 addr = (unsigned long)xen_debug; 687 else if (addr == (unsigned long)int3) 688 addr = (unsigned long)xen_int3; 689 else if (addr == (unsigned long)stack_segment) 690 addr = (unsigned long)xen_stack_segment; 691 else if (addr == (unsigned long)double_fault || 692 addr == (unsigned long)nmi) { 693 /* Don't need to handle these */ 694 return 0; 695 #ifdef CONFIG_X86_MCE 696 } else if (addr == (unsigned long)machine_check) { 697 /* 698 * when xen hypervisor inject vMCE to guest, 699 * use native mce handler to handle it 700 */ 701 ; 702 #endif 703 } else { 704 /* Some other trap using IST? */ 705 if (WARN_ON(val->ist != 0)) 706 return 0; 707 } 708 #endif /* CONFIG_X86_64 */ 709 info->address = addr; 710 711 info->cs = gate_segment(*val); 712 info->flags = val->dpl; 713 /* interrupt gates clear IF */ 714 if (val->type == GATE_INTERRUPT) 715 info->flags |= 1 << 2; 716 717 return 1; 718 } 719 720 /* Locations of each CPU's IDT */ 721 static DEFINE_PER_CPU(struct desc_ptr, idt_desc); 722 723 /* Set an IDT entry. If the entry is part of the current IDT, then 724 also update Xen. */ 725 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g) 726 { 727 unsigned long p = (unsigned long)&dt[entrynum]; 728 unsigned long start, end; 729 730 trace_xen_cpu_write_idt_entry(dt, entrynum, g); 731 732 preempt_disable(); 733 734 start = __this_cpu_read(idt_desc.address); 735 end = start + __this_cpu_read(idt_desc.size) + 1; 736 737 xen_mc_flush(); 738 739 native_write_idt_entry(dt, entrynum, g); 740 741 if (p >= start && (p + 8) <= end) { 742 struct trap_info info[2]; 743 744 info[1].address = 0; 745 746 if (cvt_gate_to_trap(entrynum, g, &info[0])) 747 if (HYPERVISOR_set_trap_table(info)) 748 BUG(); 749 } 750 751 preempt_enable(); 752 } 753 754 static void xen_convert_trap_info(const struct desc_ptr *desc, 755 struct trap_info *traps) 756 { 757 unsigned in, out, count; 758 759 count = (desc->size+1) / sizeof(gate_desc); 760 BUG_ON(count > 256); 761 762 for (in = out = 0; in < count; in++) { 763 gate_desc *entry = (gate_desc*)(desc->address) + in; 764 765 if (cvt_gate_to_trap(in, entry, &traps[out])) 766 out++; 767 } 768 traps[out].address = 0; 769 } 770 771 void xen_copy_trap_info(struct trap_info *traps) 772 { 773 const struct desc_ptr *desc = &__get_cpu_var(idt_desc); 774 775 xen_convert_trap_info(desc, traps); 776 } 777 778 /* Load a new IDT into Xen. In principle this can be per-CPU, so we 779 hold a spinlock to protect the static traps[] array (static because 780 it avoids allocation, and saves stack space). */ 781 static void xen_load_idt(const struct desc_ptr *desc) 782 { 783 static DEFINE_SPINLOCK(lock); 784 static struct trap_info traps[257]; 785 786 trace_xen_cpu_load_idt(desc); 787 788 spin_lock(&lock); 789 790 __get_cpu_var(idt_desc) = *desc; 791 792 xen_convert_trap_info(desc, traps); 793 794 xen_mc_flush(); 795 if (HYPERVISOR_set_trap_table(traps)) 796 BUG(); 797 798 spin_unlock(&lock); 799 } 800 801 /* Write a GDT descriptor entry. Ignore LDT descriptors, since 802 they're handled differently. */ 803 static void xen_write_gdt_entry(struct desc_struct *dt, int entry, 804 const void *desc, int type) 805 { 806 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); 807 808 preempt_disable(); 809 810 switch (type) { 811 case DESC_LDT: 812 case DESC_TSS: 813 /* ignore */ 814 break; 815 816 default: { 817 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]); 818 819 xen_mc_flush(); 820 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) 821 BUG(); 822 } 823 824 } 825 826 preempt_enable(); 827 } 828 829 /* 830 * Version of write_gdt_entry for use at early boot-time needed to 831 * update an entry as simply as possible. 832 */ 833 static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry, 834 const void *desc, int type) 835 { 836 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); 837 838 switch (type) { 839 case DESC_LDT: 840 case DESC_TSS: 841 /* ignore */ 842 break; 843 844 default: { 845 xmaddr_t maddr = virt_to_machine(&dt[entry]); 846 847 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) 848 dt[entry] = *(struct desc_struct *)desc; 849 } 850 851 } 852 } 853 854 static void xen_load_sp0(struct tss_struct *tss, 855 struct thread_struct *thread) 856 { 857 struct multicall_space mcs; 858 859 mcs = xen_mc_entry(0); 860 MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0); 861 xen_mc_issue(PARAVIRT_LAZY_CPU); 862 } 863 864 static void xen_set_iopl_mask(unsigned mask) 865 { 866 struct physdev_set_iopl set_iopl; 867 868 /* Force the change at ring 0. */ 869 set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3; 870 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); 871 } 872 873 static void xen_io_delay(void) 874 { 875 } 876 877 #ifdef CONFIG_X86_LOCAL_APIC 878 static unsigned long xen_set_apic_id(unsigned int x) 879 { 880 WARN_ON(1); 881 return x; 882 } 883 static unsigned int xen_get_apic_id(unsigned long x) 884 { 885 return ((x)>>24) & 0xFFu; 886 } 887 static u32 xen_apic_read(u32 reg) 888 { 889 struct xen_platform_op op = { 890 .cmd = XENPF_get_cpuinfo, 891 .interface_version = XENPF_INTERFACE_VERSION, 892 .u.pcpu_info.xen_cpuid = 0, 893 }; 894 int ret = 0; 895 896 /* Shouldn't need this as APIC is turned off for PV, and we only 897 * get called on the bootup processor. But just in case. */ 898 if (!xen_initial_domain() || smp_processor_id()) 899 return 0; 900 901 if (reg == APIC_LVR) 902 return 0x10; 903 904 if (reg != APIC_ID) 905 return 0; 906 907 ret = HYPERVISOR_dom0_op(&op); 908 if (ret) 909 return 0; 910 911 return op.u.pcpu_info.apic_id << 24; 912 } 913 914 static void xen_apic_write(u32 reg, u32 val) 915 { 916 /* Warn to see if there's any stray references */ 917 WARN_ON(1); 918 } 919 920 static u64 xen_apic_icr_read(void) 921 { 922 return 0; 923 } 924 925 static void xen_apic_icr_write(u32 low, u32 id) 926 { 927 /* Warn to see if there's any stray references */ 928 WARN_ON(1); 929 } 930 931 static void xen_apic_wait_icr_idle(void) 932 { 933 return; 934 } 935 936 static u32 xen_safe_apic_wait_icr_idle(void) 937 { 938 return 0; 939 } 940 941 static void set_xen_basic_apic_ops(void) 942 { 943 apic->read = xen_apic_read; 944 apic->write = xen_apic_write; 945 apic->icr_read = xen_apic_icr_read; 946 apic->icr_write = xen_apic_icr_write; 947 apic->wait_icr_idle = xen_apic_wait_icr_idle; 948 apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle; 949 apic->set_apic_id = xen_set_apic_id; 950 apic->get_apic_id = xen_get_apic_id; 951 952 #ifdef CONFIG_SMP 953 apic->send_IPI_allbutself = xen_send_IPI_allbutself; 954 apic->send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself; 955 apic->send_IPI_mask = xen_send_IPI_mask; 956 apic->send_IPI_all = xen_send_IPI_all; 957 apic->send_IPI_self = xen_send_IPI_self; 958 #endif 959 } 960 961 #endif 962 963 static void xen_clts(void) 964 { 965 struct multicall_space mcs; 966 967 mcs = xen_mc_entry(0); 968 969 MULTI_fpu_taskswitch(mcs.mc, 0); 970 971 xen_mc_issue(PARAVIRT_LAZY_CPU); 972 } 973 974 static DEFINE_PER_CPU(unsigned long, xen_cr0_value); 975 976 static unsigned long xen_read_cr0(void) 977 { 978 unsigned long cr0 = this_cpu_read(xen_cr0_value); 979 980 if (unlikely(cr0 == 0)) { 981 cr0 = native_read_cr0(); 982 this_cpu_write(xen_cr0_value, cr0); 983 } 984 985 return cr0; 986 } 987 988 static void xen_write_cr0(unsigned long cr0) 989 { 990 struct multicall_space mcs; 991 992 this_cpu_write(xen_cr0_value, cr0); 993 994 /* Only pay attention to cr0.TS; everything else is 995 ignored. */ 996 mcs = xen_mc_entry(0); 997 998 MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0); 999 1000 xen_mc_issue(PARAVIRT_LAZY_CPU); 1001 } 1002 1003 static void xen_write_cr4(unsigned long cr4) 1004 { 1005 cr4 &= ~X86_CR4_PGE; 1006 cr4 &= ~X86_CR4_PSE; 1007 1008 native_write_cr4(cr4); 1009 } 1010 #ifdef CONFIG_X86_64 1011 static inline unsigned long xen_read_cr8(void) 1012 { 1013 return 0; 1014 } 1015 static inline void xen_write_cr8(unsigned long val) 1016 { 1017 BUG_ON(val); 1018 } 1019 #endif 1020 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) 1021 { 1022 int ret; 1023 1024 ret = 0; 1025 1026 switch (msr) { 1027 #ifdef CONFIG_X86_64 1028 unsigned which; 1029 u64 base; 1030 1031 case MSR_FS_BASE: which = SEGBASE_FS; goto set; 1032 case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set; 1033 case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set; 1034 1035 set: 1036 base = ((u64)high << 32) | low; 1037 if (HYPERVISOR_set_segment_base(which, base) != 0) 1038 ret = -EIO; 1039 break; 1040 #endif 1041 1042 case MSR_STAR: 1043 case MSR_CSTAR: 1044 case MSR_LSTAR: 1045 case MSR_SYSCALL_MASK: 1046 case MSR_IA32_SYSENTER_CS: 1047 case MSR_IA32_SYSENTER_ESP: 1048 case MSR_IA32_SYSENTER_EIP: 1049 /* Fast syscall setup is all done in hypercalls, so 1050 these are all ignored. Stub them out here to stop 1051 Xen console noise. */ 1052 break; 1053 1054 case MSR_IA32_CR_PAT: 1055 if (smp_processor_id() == 0) 1056 xen_set_pat(((u64)high << 32) | low); 1057 break; 1058 1059 default: 1060 ret = native_write_msr_safe(msr, low, high); 1061 } 1062 1063 return ret; 1064 } 1065 1066 void xen_setup_shared_info(void) 1067 { 1068 if (!xen_feature(XENFEAT_auto_translated_physmap)) { 1069 set_fixmap(FIX_PARAVIRT_BOOTMAP, 1070 xen_start_info->shared_info); 1071 1072 HYPERVISOR_shared_info = 1073 (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP); 1074 } else 1075 HYPERVISOR_shared_info = 1076 (struct shared_info *)__va(xen_start_info->shared_info); 1077 1078 #ifndef CONFIG_SMP 1079 /* In UP this is as good a place as any to set up shared info */ 1080 xen_setup_vcpu_info_placement(); 1081 #endif 1082 1083 xen_setup_mfn_list_list(); 1084 } 1085 1086 /* This is called once we have the cpu_possible_mask */ 1087 void xen_setup_vcpu_info_placement(void) 1088 { 1089 int cpu; 1090 1091 for_each_possible_cpu(cpu) 1092 xen_vcpu_setup(cpu); 1093 1094 /* xen_vcpu_setup managed to place the vcpu_info within the 1095 percpu area for all cpus, so make use of it */ 1096 if (have_vcpu_info_placement) { 1097 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct); 1098 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct); 1099 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct); 1100 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct); 1101 pv_mmu_ops.read_cr2 = xen_read_cr2_direct; 1102 } 1103 } 1104 1105 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf, 1106 unsigned long addr, unsigned len) 1107 { 1108 char *start, *end, *reloc; 1109 unsigned ret; 1110 1111 start = end = reloc = NULL; 1112 1113 #define SITE(op, x) \ 1114 case PARAVIRT_PATCH(op.x): \ 1115 if (have_vcpu_info_placement) { \ 1116 start = (char *)xen_##x##_direct; \ 1117 end = xen_##x##_direct_end; \ 1118 reloc = xen_##x##_direct_reloc; \ 1119 } \ 1120 goto patch_site 1121 1122 switch (type) { 1123 SITE(pv_irq_ops, irq_enable); 1124 SITE(pv_irq_ops, irq_disable); 1125 SITE(pv_irq_ops, save_fl); 1126 SITE(pv_irq_ops, restore_fl); 1127 #undef SITE 1128 1129 patch_site: 1130 if (start == NULL || (end-start) > len) 1131 goto default_patch; 1132 1133 ret = paravirt_patch_insns(insnbuf, len, start, end); 1134 1135 /* Note: because reloc is assigned from something that 1136 appears to be an array, gcc assumes it's non-null, 1137 but doesn't know its relationship with start and 1138 end. */ 1139 if (reloc > start && reloc < end) { 1140 int reloc_off = reloc - start; 1141 long *relocp = (long *)(insnbuf + reloc_off); 1142 long delta = start - (char *)addr; 1143 1144 *relocp += delta; 1145 } 1146 break; 1147 1148 default_patch: 1149 default: 1150 ret = paravirt_patch_default(type, clobbers, insnbuf, 1151 addr, len); 1152 break; 1153 } 1154 1155 return ret; 1156 } 1157 1158 static const struct pv_info xen_info __initconst = { 1159 .paravirt_enabled = 1, 1160 .shared_kernel_pmd = 0, 1161 1162 #ifdef CONFIG_X86_64 1163 .extra_user_64bit_cs = FLAT_USER_CS64, 1164 #endif 1165 1166 .name = "Xen", 1167 }; 1168 1169 static const struct pv_init_ops xen_init_ops __initconst = { 1170 .patch = xen_patch, 1171 }; 1172 1173 static const struct pv_cpu_ops xen_cpu_ops __initconst = { 1174 .cpuid = xen_cpuid, 1175 1176 .set_debugreg = xen_set_debugreg, 1177 .get_debugreg = xen_get_debugreg, 1178 1179 .clts = xen_clts, 1180 1181 .read_cr0 = xen_read_cr0, 1182 .write_cr0 = xen_write_cr0, 1183 1184 .read_cr4 = native_read_cr4, 1185 .read_cr4_safe = native_read_cr4_safe, 1186 .write_cr4 = xen_write_cr4, 1187 1188 #ifdef CONFIG_X86_64 1189 .read_cr8 = xen_read_cr8, 1190 .write_cr8 = xen_write_cr8, 1191 #endif 1192 1193 .wbinvd = native_wbinvd, 1194 1195 .read_msr = native_read_msr_safe, 1196 .write_msr = xen_write_msr_safe, 1197 1198 .read_tsc = native_read_tsc, 1199 .read_pmc = native_read_pmc, 1200 1201 .read_tscp = native_read_tscp, 1202 1203 .iret = xen_iret, 1204 .irq_enable_sysexit = xen_sysexit, 1205 #ifdef CONFIG_X86_64 1206 .usergs_sysret32 = xen_sysret32, 1207 .usergs_sysret64 = xen_sysret64, 1208 #endif 1209 1210 .load_tr_desc = paravirt_nop, 1211 .set_ldt = xen_set_ldt, 1212 .load_gdt = xen_load_gdt, 1213 .load_idt = xen_load_idt, 1214 .load_tls = xen_load_tls, 1215 #ifdef CONFIG_X86_64 1216 .load_gs_index = xen_load_gs_index, 1217 #endif 1218 1219 .alloc_ldt = xen_alloc_ldt, 1220 .free_ldt = xen_free_ldt, 1221 1222 .store_gdt = native_store_gdt, 1223 .store_idt = native_store_idt, 1224 .store_tr = xen_store_tr, 1225 1226 .write_ldt_entry = xen_write_ldt_entry, 1227 .write_gdt_entry = xen_write_gdt_entry, 1228 .write_idt_entry = xen_write_idt_entry, 1229 .load_sp0 = xen_load_sp0, 1230 1231 .set_iopl_mask = xen_set_iopl_mask, 1232 .io_delay = xen_io_delay, 1233 1234 /* Xen takes care of %gs when switching to usermode for us */ 1235 .swapgs = paravirt_nop, 1236 1237 .start_context_switch = paravirt_start_context_switch, 1238 .end_context_switch = xen_end_context_switch, 1239 }; 1240 1241 static const struct pv_apic_ops xen_apic_ops __initconst = { 1242 #ifdef CONFIG_X86_LOCAL_APIC 1243 .startup_ipi_hook = paravirt_nop, 1244 #endif 1245 }; 1246 1247 static void xen_reboot(int reason) 1248 { 1249 struct sched_shutdown r = { .reason = reason }; 1250 1251 if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r)) 1252 BUG(); 1253 } 1254 1255 static void xen_restart(char *msg) 1256 { 1257 xen_reboot(SHUTDOWN_reboot); 1258 } 1259 1260 static void xen_emergency_restart(void) 1261 { 1262 xen_reboot(SHUTDOWN_reboot); 1263 } 1264 1265 static void xen_machine_halt(void) 1266 { 1267 xen_reboot(SHUTDOWN_poweroff); 1268 } 1269 1270 static void xen_machine_power_off(void) 1271 { 1272 if (pm_power_off) 1273 pm_power_off(); 1274 xen_reboot(SHUTDOWN_poweroff); 1275 } 1276 1277 static void xen_crash_shutdown(struct pt_regs *regs) 1278 { 1279 xen_reboot(SHUTDOWN_crash); 1280 } 1281 1282 static int 1283 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr) 1284 { 1285 xen_reboot(SHUTDOWN_crash); 1286 return NOTIFY_DONE; 1287 } 1288 1289 static struct notifier_block xen_panic_block = { 1290 .notifier_call= xen_panic_event, 1291 }; 1292 1293 int xen_panic_handler_init(void) 1294 { 1295 atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block); 1296 return 0; 1297 } 1298 1299 static const struct machine_ops xen_machine_ops __initconst = { 1300 .restart = xen_restart, 1301 .halt = xen_machine_halt, 1302 .power_off = xen_machine_power_off, 1303 .shutdown = xen_machine_halt, 1304 .crash_shutdown = xen_crash_shutdown, 1305 .emergency_restart = xen_emergency_restart, 1306 }; 1307 1308 /* 1309 * Set up the GDT and segment registers for -fstack-protector. Until 1310 * we do this, we have to be careful not to call any stack-protected 1311 * function, which is most of the kernel. 1312 */ 1313 static void __init xen_setup_stackprotector(void) 1314 { 1315 pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot; 1316 pv_cpu_ops.load_gdt = xen_load_gdt_boot; 1317 1318 setup_stack_canary_segment(0); 1319 switch_to_new_gdt(0); 1320 1321 pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry; 1322 pv_cpu_ops.load_gdt = xen_load_gdt; 1323 } 1324 1325 /* First C function to be called on Xen boot */ 1326 asmlinkage void __init xen_start_kernel(void) 1327 { 1328 struct physdev_set_iopl set_iopl; 1329 int rc; 1330 1331 if (!xen_start_info) 1332 return; 1333 1334 xen_domain_type = XEN_PV_DOMAIN; 1335 1336 xen_setup_machphys_mapping(); 1337 1338 /* Install Xen paravirt ops */ 1339 pv_info = xen_info; 1340 pv_init_ops = xen_init_ops; 1341 pv_cpu_ops = xen_cpu_ops; 1342 pv_apic_ops = xen_apic_ops; 1343 1344 x86_init.resources.memory_setup = xen_memory_setup; 1345 x86_init.oem.arch_setup = xen_arch_setup; 1346 x86_init.oem.banner = xen_banner; 1347 1348 xen_init_time_ops(); 1349 1350 /* 1351 * Set up some pagetable state before starting to set any ptes. 1352 */ 1353 1354 xen_init_mmu_ops(); 1355 1356 /* Prevent unwanted bits from being set in PTEs. */ 1357 __supported_pte_mask &= ~_PAGE_GLOBAL; 1358 #if 0 1359 if (!xen_initial_domain()) 1360 #endif 1361 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); 1362 1363 __supported_pte_mask |= _PAGE_IOMAP; 1364 1365 /* 1366 * Prevent page tables from being allocated in highmem, even 1367 * if CONFIG_HIGHPTE is enabled. 1368 */ 1369 __userpte_alloc_gfp &= ~__GFP_HIGHMEM; 1370 1371 /* Work out if we support NX */ 1372 x86_configure_nx(); 1373 1374 xen_setup_features(); 1375 1376 /* Get mfn list */ 1377 if (!xen_feature(XENFEAT_auto_translated_physmap)) 1378 xen_build_dynamic_phys_to_machine(); 1379 1380 /* 1381 * Set up kernel GDT and segment registers, mainly so that 1382 * -fstack-protector code can be executed. 1383 */ 1384 xen_setup_stackprotector(); 1385 1386 xen_init_irq_ops(); 1387 xen_init_cpuid_mask(); 1388 1389 #ifdef CONFIG_X86_LOCAL_APIC 1390 /* 1391 * set up the basic apic ops. 1392 */ 1393 set_xen_basic_apic_ops(); 1394 #endif 1395 1396 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) { 1397 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start; 1398 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit; 1399 } 1400 1401 machine_ops = xen_machine_ops; 1402 1403 /* 1404 * The only reliable way to retain the initial address of the 1405 * percpu gdt_page is to remember it here, so we can go and 1406 * mark it RW later, when the initial percpu area is freed. 1407 */ 1408 xen_initial_gdt = &per_cpu(gdt_page, 0); 1409 1410 xen_smp_init(); 1411 1412 #ifdef CONFIG_ACPI_NUMA 1413 /* 1414 * The pages we from Xen are not related to machine pages, so 1415 * any NUMA information the kernel tries to get from ACPI will 1416 * be meaningless. Prevent it from trying. 1417 */ 1418 acpi_numa = -1; 1419 #endif 1420 1421 /* Don't do the full vcpu_info placement stuff until we have a 1422 possible map and a non-dummy shared_info. */ 1423 per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; 1424 1425 local_irq_disable(); 1426 early_boot_irqs_disabled = true; 1427 1428 xen_raw_console_write("mapping kernel into physical memory\n"); 1429 xen_setup_kernel_pagetable((pgd_t *)xen_start_info->pt_base, xen_start_info->nr_pages); 1430 1431 /* Allocate and initialize top and mid mfn levels for p2m structure */ 1432 xen_build_mfn_list_list(); 1433 1434 /* keep using Xen gdt for now; no urgent need to change it */ 1435 1436 #ifdef CONFIG_X86_32 1437 pv_info.kernel_rpl = 1; 1438 if (xen_feature(XENFEAT_supervisor_mode_kernel)) 1439 pv_info.kernel_rpl = 0; 1440 #else 1441 pv_info.kernel_rpl = 0; 1442 #endif 1443 /* set the limit of our address space */ 1444 xen_reserve_top(); 1445 1446 /* We used to do this in xen_arch_setup, but that is too late on AMD 1447 * were early_cpu_init (run before ->arch_setup()) calls early_amd_init 1448 * which pokes 0xcf8 port. 1449 */ 1450 set_iopl.iopl = 1; 1451 rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); 1452 if (rc != 0) 1453 xen_raw_printk("physdev_op failed %d\n", rc); 1454 1455 #ifdef CONFIG_X86_32 1456 /* set up basic CPUID stuff */ 1457 cpu_detect(&new_cpu_data); 1458 new_cpu_data.hard_math = 1; 1459 new_cpu_data.wp_works_ok = 1; 1460 new_cpu_data.x86_capability[0] = cpuid_edx(1); 1461 #endif 1462 1463 /* Poke various useful things into boot_params */ 1464 boot_params.hdr.type_of_loader = (9 << 4) | 0; 1465 boot_params.hdr.ramdisk_image = xen_start_info->mod_start 1466 ? __pa(xen_start_info->mod_start) : 0; 1467 boot_params.hdr.ramdisk_size = xen_start_info->mod_len; 1468 boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line); 1469 1470 if (!xen_initial_domain()) { 1471 add_preferred_console("xenboot", 0, NULL); 1472 add_preferred_console("tty", 0, NULL); 1473 add_preferred_console("hvc", 0, NULL); 1474 if (pci_xen) 1475 x86_init.pci.arch_init = pci_xen_init; 1476 } else { 1477 const struct dom0_vga_console_info *info = 1478 (void *)((char *)xen_start_info + 1479 xen_start_info->console.dom0.info_off); 1480 struct xen_platform_op op = { 1481 .cmd = XENPF_firmware_info, 1482 .interface_version = XENPF_INTERFACE_VERSION, 1483 .u.firmware_info.type = XEN_FW_KBD_SHIFT_FLAGS, 1484 }; 1485 1486 xen_init_vga(info, xen_start_info->console.dom0.info_size); 1487 xen_start_info->console.domU.mfn = 0; 1488 xen_start_info->console.domU.evtchn = 0; 1489 1490 if (HYPERVISOR_dom0_op(&op) == 0) 1491 boot_params.kbd_status = op.u.firmware_info.u.kbd_shift_flags; 1492 1493 xen_init_apic(); 1494 1495 /* Make sure ACS will be enabled */ 1496 pci_request_acs(); 1497 1498 xen_acpi_sleep_register(); 1499 1500 /* Avoid searching for BIOS MP tables */ 1501 x86_init.mpparse.find_smp_config = x86_init_noop; 1502 x86_init.mpparse.get_smp_config = x86_init_uint_noop; 1503 } 1504 #ifdef CONFIG_PCI 1505 /* PCI BIOS service won't work from a PV guest. */ 1506 pci_probe &= ~PCI_PROBE_BIOS; 1507 #endif 1508 xen_raw_console_write("about to get started...\n"); 1509 1510 xen_setup_runstate_info(0); 1511 1512 /* Start the world */ 1513 #ifdef CONFIG_X86_32 1514 i386_start_kernel(); 1515 #else 1516 x86_64_start_reservations((char *)__pa_symbol(&boot_params)); 1517 #endif 1518 } 1519 1520 void __ref xen_hvm_init_shared_info(void) 1521 { 1522 int cpu; 1523 struct xen_add_to_physmap xatp; 1524 static struct shared_info *shared_info_page = 0; 1525 1526 if (!shared_info_page) 1527 shared_info_page = (struct shared_info *) 1528 extend_brk(PAGE_SIZE, PAGE_SIZE); 1529 xatp.domid = DOMID_SELF; 1530 xatp.idx = 0; 1531 xatp.space = XENMAPSPACE_shared_info; 1532 xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT; 1533 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 1534 BUG(); 1535 1536 HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; 1537 1538 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info 1539 * page, we use it in the event channel upcall and in some pvclock 1540 * related functions. We don't need the vcpu_info placement 1541 * optimizations because we don't use any pv_mmu or pv_irq op on 1542 * HVM. 1543 * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is 1544 * online but xen_hvm_init_shared_info is run at resume time too and 1545 * in that case multiple vcpus might be online. */ 1546 for_each_online_cpu(cpu) { 1547 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; 1548 } 1549 } 1550 1551 #ifdef CONFIG_XEN_PVHVM 1552 static void __init init_hvm_pv_info(void) 1553 { 1554 int major, minor; 1555 uint32_t eax, ebx, ecx, edx, pages, msr, base; 1556 u64 pfn; 1557 1558 base = xen_cpuid_base(); 1559 cpuid(base + 1, &eax, &ebx, &ecx, &edx); 1560 1561 major = eax >> 16; 1562 minor = eax & 0xffff; 1563 printk(KERN_INFO "Xen version %d.%d.\n", major, minor); 1564 1565 cpuid(base + 2, &pages, &msr, &ecx, &edx); 1566 1567 pfn = __pa(hypercall_page); 1568 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32)); 1569 1570 xen_setup_features(); 1571 1572 pv_info.name = "Xen HVM"; 1573 1574 xen_domain_type = XEN_HVM_DOMAIN; 1575 } 1576 1577 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self, 1578 unsigned long action, void *hcpu) 1579 { 1580 int cpu = (long)hcpu; 1581 switch (action) { 1582 case CPU_UP_PREPARE: 1583 xen_vcpu_setup(cpu); 1584 if (xen_have_vector_callback) 1585 xen_init_lock_cpu(cpu); 1586 break; 1587 default: 1588 break; 1589 } 1590 return NOTIFY_OK; 1591 } 1592 1593 static struct notifier_block xen_hvm_cpu_notifier __cpuinitdata = { 1594 .notifier_call = xen_hvm_cpu_notify, 1595 }; 1596 1597 static void __init xen_hvm_guest_init(void) 1598 { 1599 init_hvm_pv_info(); 1600 1601 xen_hvm_init_shared_info(); 1602 1603 if (xen_feature(XENFEAT_hvm_callback_vector)) 1604 xen_have_vector_callback = 1; 1605 xen_hvm_smp_init(); 1606 register_cpu_notifier(&xen_hvm_cpu_notifier); 1607 xen_unplug_emulated_devices(); 1608 x86_init.irqs.intr_init = xen_init_IRQ; 1609 xen_hvm_init_time_ops(); 1610 xen_hvm_init_mmu_ops(); 1611 } 1612 1613 static bool __init xen_hvm_platform(void) 1614 { 1615 if (xen_pv_domain()) 1616 return false; 1617 1618 if (!xen_cpuid_base()) 1619 return false; 1620 1621 return true; 1622 } 1623 1624 bool xen_hvm_need_lapic(void) 1625 { 1626 if (xen_pv_domain()) 1627 return false; 1628 if (!xen_hvm_domain()) 1629 return false; 1630 if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback) 1631 return false; 1632 return true; 1633 } 1634 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic); 1635 1636 const struct hypervisor_x86 x86_hyper_xen_hvm __refconst = { 1637 .name = "Xen HVM", 1638 .detect = xen_hvm_platform, 1639 .init_platform = xen_hvm_guest_init, 1640 .x2apic_available = xen_x2apic_para_available, 1641 }; 1642 EXPORT_SYMBOL(x86_hyper_xen_hvm); 1643 #endif 1644