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 #include <asm/mwait.h> 66 #include <asm/pci_x86.h> 67 68 #ifdef CONFIG_ACPI 69 #include <linux/acpi.h> 70 #include <asm/acpi.h> 71 #include <acpi/pdc_intel.h> 72 #include <acpi/processor.h> 73 #include <xen/interface/platform.h> 74 #endif 75 76 #include "xen-ops.h" 77 #include "mmu.h" 78 #include "multicalls.h" 79 80 EXPORT_SYMBOL_GPL(hypercall_page); 81 82 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); 83 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info); 84 85 enum xen_domain_type xen_domain_type = XEN_NATIVE; 86 EXPORT_SYMBOL_GPL(xen_domain_type); 87 88 unsigned long *machine_to_phys_mapping = (void *)MACH2PHYS_VIRT_START; 89 EXPORT_SYMBOL(machine_to_phys_mapping); 90 unsigned long machine_to_phys_nr; 91 EXPORT_SYMBOL(machine_to_phys_nr); 92 93 struct start_info *xen_start_info; 94 EXPORT_SYMBOL_GPL(xen_start_info); 95 96 struct shared_info xen_dummy_shared_info; 97 98 void *xen_initial_gdt; 99 100 RESERVE_BRK(shared_info_page_brk, PAGE_SIZE); 101 __read_mostly int xen_have_vector_callback; 102 EXPORT_SYMBOL_GPL(xen_have_vector_callback); 103 104 /* 105 * Point at some empty memory to start with. We map the real shared_info 106 * page as soon as fixmap is up and running. 107 */ 108 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; 109 110 /* 111 * Flag to determine whether vcpu info placement is available on all 112 * VCPUs. We assume it is to start with, and then set it to zero on 113 * the first failure. This is because it can succeed on some VCPUs 114 * and not others, since it can involve hypervisor memory allocation, 115 * or because the guest failed to guarantee all the appropriate 116 * constraints on all VCPUs (ie buffer can't cross a page boundary). 117 * 118 * Note that any particular CPU may be using a placed vcpu structure, 119 * but we can only optimise if the all are. 120 * 121 * 0: not available, 1: available 122 */ 123 static int have_vcpu_info_placement = 1; 124 125 static void clamp_max_cpus(void) 126 { 127 #ifdef CONFIG_SMP 128 if (setup_max_cpus > MAX_VIRT_CPUS) 129 setup_max_cpus = MAX_VIRT_CPUS; 130 #endif 131 } 132 133 static void xen_vcpu_setup(int cpu) 134 { 135 struct vcpu_register_vcpu_info info; 136 int err; 137 struct vcpu_info *vcpup; 138 139 BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info); 140 141 if (cpu < MAX_VIRT_CPUS) 142 per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; 143 144 if (!have_vcpu_info_placement) { 145 if (cpu >= MAX_VIRT_CPUS) 146 clamp_max_cpus(); 147 return; 148 } 149 150 vcpup = &per_cpu(xen_vcpu_info, cpu); 151 info.mfn = arbitrary_virt_to_mfn(vcpup); 152 info.offset = offset_in_page(vcpup); 153 154 /* Check to see if the hypervisor will put the vcpu_info 155 structure where we want it, which allows direct access via 156 a percpu-variable. */ 157 err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); 158 159 if (err) { 160 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err); 161 have_vcpu_info_placement = 0; 162 clamp_max_cpus(); 163 } else { 164 /* This cpu is using the registered vcpu info, even if 165 later ones fail to. */ 166 per_cpu(xen_vcpu, cpu) = vcpup; 167 } 168 } 169 170 /* 171 * On restore, set the vcpu placement up again. 172 * If it fails, then we're in a bad state, since 173 * we can't back out from using it... 174 */ 175 void xen_vcpu_restore(void) 176 { 177 int cpu; 178 179 for_each_online_cpu(cpu) { 180 bool other_cpu = (cpu != smp_processor_id()); 181 182 if (other_cpu && 183 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL)) 184 BUG(); 185 186 xen_setup_runstate_info(cpu); 187 188 if (have_vcpu_info_placement) 189 xen_vcpu_setup(cpu); 190 191 if (other_cpu && 192 HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL)) 193 BUG(); 194 } 195 } 196 197 static void __init xen_banner(void) 198 { 199 unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL); 200 struct xen_extraversion extra; 201 HYPERVISOR_xen_version(XENVER_extraversion, &extra); 202 203 printk(KERN_INFO "Booting paravirtualized kernel on %s\n", 204 pv_info.name); 205 printk(KERN_INFO "Xen version: %d.%d%s%s\n", 206 version >> 16, version & 0xffff, extra.extraversion, 207 xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); 208 } 209 210 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0; 211 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0; 212 213 static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask; 214 static __read_mostly unsigned int cpuid_leaf5_ecx_val; 215 static __read_mostly unsigned int cpuid_leaf5_edx_val; 216 217 static void xen_cpuid(unsigned int *ax, unsigned int *bx, 218 unsigned int *cx, unsigned int *dx) 219 { 220 unsigned maskebx = ~0; 221 unsigned maskecx = ~0; 222 unsigned maskedx = ~0; 223 unsigned setecx = 0; 224 /* 225 * Mask out inconvenient features, to try and disable as many 226 * unsupported kernel subsystems as possible. 227 */ 228 switch (*ax) { 229 case 1: 230 maskecx = cpuid_leaf1_ecx_mask; 231 setecx = cpuid_leaf1_ecx_set_mask; 232 maskedx = cpuid_leaf1_edx_mask; 233 break; 234 235 case CPUID_MWAIT_LEAF: 236 /* Synthesize the values.. */ 237 *ax = 0; 238 *bx = 0; 239 *cx = cpuid_leaf5_ecx_val; 240 *dx = cpuid_leaf5_edx_val; 241 return; 242 243 case 0xb: 244 /* Suppress extended topology stuff */ 245 maskebx = 0; 246 break; 247 } 248 249 asm(XEN_EMULATE_PREFIX "cpuid" 250 : "=a" (*ax), 251 "=b" (*bx), 252 "=c" (*cx), 253 "=d" (*dx) 254 : "0" (*ax), "2" (*cx)); 255 256 *bx &= maskebx; 257 *cx &= maskecx; 258 *cx |= setecx; 259 *dx &= maskedx; 260 261 } 262 263 static bool __init xen_check_mwait(void) 264 { 265 #if defined(CONFIG_ACPI) && !defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) && \ 266 !defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE) 267 struct xen_platform_op op = { 268 .cmd = XENPF_set_processor_pminfo, 269 .u.set_pminfo.id = -1, 270 .u.set_pminfo.type = XEN_PM_PDC, 271 }; 272 uint32_t buf[3]; 273 unsigned int ax, bx, cx, dx; 274 unsigned int mwait_mask; 275 276 /* We need to determine whether it is OK to expose the MWAIT 277 * capability to the kernel to harvest deeper than C3 states from ACPI 278 * _CST using the processor_harvest_xen.c module. For this to work, we 279 * need to gather the MWAIT_LEAF values (which the cstate.c code 280 * checks against). The hypervisor won't expose the MWAIT flag because 281 * it would break backwards compatibility; so we will find out directly 282 * from the hardware and hypercall. 283 */ 284 if (!xen_initial_domain()) 285 return false; 286 287 ax = 1; 288 cx = 0; 289 290 native_cpuid(&ax, &bx, &cx, &dx); 291 292 mwait_mask = (1 << (X86_FEATURE_EST % 32)) | 293 (1 << (X86_FEATURE_MWAIT % 32)); 294 295 if ((cx & mwait_mask) != mwait_mask) 296 return false; 297 298 /* We need to emulate the MWAIT_LEAF and for that we need both 299 * ecx and edx. The hypercall provides only partial information. 300 */ 301 302 ax = CPUID_MWAIT_LEAF; 303 bx = 0; 304 cx = 0; 305 dx = 0; 306 307 native_cpuid(&ax, &bx, &cx, &dx); 308 309 /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so, 310 * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3. 311 */ 312 buf[0] = ACPI_PDC_REVISION_ID; 313 buf[1] = 1; 314 buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP); 315 316 set_xen_guest_handle(op.u.set_pminfo.pdc, buf); 317 318 if ((HYPERVISOR_dom0_op(&op) == 0) && 319 (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) { 320 cpuid_leaf5_ecx_val = cx; 321 cpuid_leaf5_edx_val = dx; 322 } 323 return true; 324 #else 325 return false; 326 #endif 327 } 328 static void __init xen_init_cpuid_mask(void) 329 { 330 unsigned int ax, bx, cx, dx; 331 unsigned int xsave_mask; 332 333 cpuid_leaf1_edx_mask = 334 ~((1 << X86_FEATURE_MCE) | /* disable MCE */ 335 (1 << X86_FEATURE_MCA) | /* disable MCA */ 336 (1 << X86_FEATURE_MTRR) | /* disable MTRR */ 337 (1 << X86_FEATURE_ACC)); /* thermal monitoring */ 338 339 if (!xen_initial_domain()) 340 cpuid_leaf1_edx_mask &= 341 ~((1 << X86_FEATURE_APIC) | /* disable local APIC */ 342 (1 << X86_FEATURE_ACPI)); /* disable ACPI */ 343 ax = 1; 344 cx = 0; 345 xen_cpuid(&ax, &bx, &cx, &dx); 346 347 xsave_mask = 348 (1 << (X86_FEATURE_XSAVE % 32)) | 349 (1 << (X86_FEATURE_OSXSAVE % 32)); 350 351 /* Xen will set CR4.OSXSAVE if supported and not disabled by force */ 352 if ((cx & xsave_mask) != xsave_mask) 353 cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */ 354 if (xen_check_mwait()) 355 cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32)); 356 } 357 358 static void xen_set_debugreg(int reg, unsigned long val) 359 { 360 HYPERVISOR_set_debugreg(reg, val); 361 } 362 363 static unsigned long xen_get_debugreg(int reg) 364 { 365 return HYPERVISOR_get_debugreg(reg); 366 } 367 368 static void xen_end_context_switch(struct task_struct *next) 369 { 370 xen_mc_flush(); 371 paravirt_end_context_switch(next); 372 } 373 374 static unsigned long xen_store_tr(void) 375 { 376 return 0; 377 } 378 379 /* 380 * Set the page permissions for a particular virtual address. If the 381 * address is a vmalloc mapping (or other non-linear mapping), then 382 * find the linear mapping of the page and also set its protections to 383 * match. 384 */ 385 static void set_aliased_prot(void *v, pgprot_t prot) 386 { 387 int level; 388 pte_t *ptep; 389 pte_t pte; 390 unsigned long pfn; 391 struct page *page; 392 393 ptep = lookup_address((unsigned long)v, &level); 394 BUG_ON(ptep == NULL); 395 396 pfn = pte_pfn(*ptep); 397 page = pfn_to_page(pfn); 398 399 pte = pfn_pte(pfn, prot); 400 401 if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0)) 402 BUG(); 403 404 if (!PageHighMem(page)) { 405 void *av = __va(PFN_PHYS(pfn)); 406 407 if (av != v) 408 if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0)) 409 BUG(); 410 } else 411 kmap_flush_unused(); 412 } 413 414 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries) 415 { 416 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; 417 int i; 418 419 for(i = 0; i < entries; i += entries_per_page) 420 set_aliased_prot(ldt + i, PAGE_KERNEL_RO); 421 } 422 423 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries) 424 { 425 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE; 426 int i; 427 428 for(i = 0; i < entries; i += entries_per_page) 429 set_aliased_prot(ldt + i, PAGE_KERNEL); 430 } 431 432 static void xen_set_ldt(const void *addr, unsigned entries) 433 { 434 struct mmuext_op *op; 435 struct multicall_space mcs = xen_mc_entry(sizeof(*op)); 436 437 trace_xen_cpu_set_ldt(addr, entries); 438 439 op = mcs.args; 440 op->cmd = MMUEXT_SET_LDT; 441 op->arg1.linear_addr = (unsigned long)addr; 442 op->arg2.nr_ents = entries; 443 444 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); 445 446 xen_mc_issue(PARAVIRT_LAZY_CPU); 447 } 448 449 static void xen_load_gdt(const struct desc_ptr *dtr) 450 { 451 unsigned long va = dtr->address; 452 unsigned int size = dtr->size + 1; 453 unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE; 454 unsigned long frames[pages]; 455 int f; 456 457 /* 458 * A GDT can be up to 64k in size, which corresponds to 8192 459 * 8-byte entries, or 16 4k pages.. 460 */ 461 462 BUG_ON(size > 65536); 463 BUG_ON(va & ~PAGE_MASK); 464 465 for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { 466 int level; 467 pte_t *ptep; 468 unsigned long pfn, mfn; 469 void *virt; 470 471 /* 472 * The GDT is per-cpu and is in the percpu data area. 473 * That can be virtually mapped, so we need to do a 474 * page-walk to get the underlying MFN for the 475 * hypercall. The page can also be in the kernel's 476 * linear range, so we need to RO that mapping too. 477 */ 478 ptep = lookup_address(va, &level); 479 BUG_ON(ptep == NULL); 480 481 pfn = pte_pfn(*ptep); 482 mfn = pfn_to_mfn(pfn); 483 virt = __va(PFN_PHYS(pfn)); 484 485 frames[f] = mfn; 486 487 make_lowmem_page_readonly((void *)va); 488 make_lowmem_page_readonly(virt); 489 } 490 491 if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) 492 BUG(); 493 } 494 495 /* 496 * load_gdt for early boot, when the gdt is only mapped once 497 */ 498 static void __init xen_load_gdt_boot(const struct desc_ptr *dtr) 499 { 500 unsigned long va = dtr->address; 501 unsigned int size = dtr->size + 1; 502 unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE; 503 unsigned long frames[pages]; 504 int f; 505 506 /* 507 * A GDT can be up to 64k in size, which corresponds to 8192 508 * 8-byte entries, or 16 4k pages.. 509 */ 510 511 BUG_ON(size > 65536); 512 BUG_ON(va & ~PAGE_MASK); 513 514 for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { 515 pte_t pte; 516 unsigned long pfn, mfn; 517 518 pfn = virt_to_pfn(va); 519 mfn = pfn_to_mfn(pfn); 520 521 pte = pfn_pte(pfn, PAGE_KERNEL_RO); 522 523 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0)) 524 BUG(); 525 526 frames[f] = mfn; 527 } 528 529 if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) 530 BUG(); 531 } 532 533 static void load_TLS_descriptor(struct thread_struct *t, 534 unsigned int cpu, unsigned int i) 535 { 536 struct desc_struct *gdt = get_cpu_gdt_table(cpu); 537 xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]); 538 struct multicall_space mc = __xen_mc_entry(0); 539 540 MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]); 541 } 542 543 static void xen_load_tls(struct thread_struct *t, unsigned int cpu) 544 { 545 /* 546 * XXX sleazy hack: If we're being called in a lazy-cpu zone 547 * and lazy gs handling is enabled, it means we're in a 548 * context switch, and %gs has just been saved. This means we 549 * can zero it out to prevent faults on exit from the 550 * hypervisor if the next process has no %gs. Either way, it 551 * has been saved, and the new value will get loaded properly. 552 * This will go away as soon as Xen has been modified to not 553 * save/restore %gs for normal hypercalls. 554 * 555 * On x86_64, this hack is not used for %gs, because gs points 556 * to KERNEL_GS_BASE (and uses it for PDA references), so we 557 * must not zero %gs on x86_64 558 * 559 * For x86_64, we need to zero %fs, otherwise we may get an 560 * exception between the new %fs descriptor being loaded and 561 * %fs being effectively cleared at __switch_to(). 562 */ 563 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { 564 #ifdef CONFIG_X86_32 565 lazy_load_gs(0); 566 #else 567 loadsegment(fs, 0); 568 #endif 569 } 570 571 xen_mc_batch(); 572 573 load_TLS_descriptor(t, cpu, 0); 574 load_TLS_descriptor(t, cpu, 1); 575 load_TLS_descriptor(t, cpu, 2); 576 577 xen_mc_issue(PARAVIRT_LAZY_CPU); 578 } 579 580 #ifdef CONFIG_X86_64 581 static void xen_load_gs_index(unsigned int idx) 582 { 583 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx)) 584 BUG(); 585 } 586 #endif 587 588 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, 589 const void *ptr) 590 { 591 xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]); 592 u64 entry = *(u64 *)ptr; 593 594 trace_xen_cpu_write_ldt_entry(dt, entrynum, entry); 595 596 preempt_disable(); 597 598 xen_mc_flush(); 599 if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry)) 600 BUG(); 601 602 preempt_enable(); 603 } 604 605 static int cvt_gate_to_trap(int vector, const gate_desc *val, 606 struct trap_info *info) 607 { 608 unsigned long addr; 609 610 if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT) 611 return 0; 612 613 info->vector = vector; 614 615 addr = gate_offset(*val); 616 #ifdef CONFIG_X86_64 617 /* 618 * Look for known traps using IST, and substitute them 619 * appropriately. The debugger ones are the only ones we care 620 * about. Xen will handle faults like double_fault and 621 * machine_check, so we should never see them. Warn if 622 * there's an unexpected IST-using fault handler. 623 */ 624 if (addr == (unsigned long)debug) 625 addr = (unsigned long)xen_debug; 626 else if (addr == (unsigned long)int3) 627 addr = (unsigned long)xen_int3; 628 else if (addr == (unsigned long)stack_segment) 629 addr = (unsigned long)xen_stack_segment; 630 else if (addr == (unsigned long)double_fault || 631 addr == (unsigned long)nmi) { 632 /* Don't need to handle these */ 633 return 0; 634 #ifdef CONFIG_X86_MCE 635 } else if (addr == (unsigned long)machine_check) { 636 return 0; 637 #endif 638 } else { 639 /* Some other trap using IST? */ 640 if (WARN_ON(val->ist != 0)) 641 return 0; 642 } 643 #endif /* CONFIG_X86_64 */ 644 info->address = addr; 645 646 info->cs = gate_segment(*val); 647 info->flags = val->dpl; 648 /* interrupt gates clear IF */ 649 if (val->type == GATE_INTERRUPT) 650 info->flags |= 1 << 2; 651 652 return 1; 653 } 654 655 /* Locations of each CPU's IDT */ 656 static DEFINE_PER_CPU(struct desc_ptr, idt_desc); 657 658 /* Set an IDT entry. If the entry is part of the current IDT, then 659 also update Xen. */ 660 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g) 661 { 662 unsigned long p = (unsigned long)&dt[entrynum]; 663 unsigned long start, end; 664 665 trace_xen_cpu_write_idt_entry(dt, entrynum, g); 666 667 preempt_disable(); 668 669 start = __this_cpu_read(idt_desc.address); 670 end = start + __this_cpu_read(idt_desc.size) + 1; 671 672 xen_mc_flush(); 673 674 native_write_idt_entry(dt, entrynum, g); 675 676 if (p >= start && (p + 8) <= end) { 677 struct trap_info info[2]; 678 679 info[1].address = 0; 680 681 if (cvt_gate_to_trap(entrynum, g, &info[0])) 682 if (HYPERVISOR_set_trap_table(info)) 683 BUG(); 684 } 685 686 preempt_enable(); 687 } 688 689 static void xen_convert_trap_info(const struct desc_ptr *desc, 690 struct trap_info *traps) 691 { 692 unsigned in, out, count; 693 694 count = (desc->size+1) / sizeof(gate_desc); 695 BUG_ON(count > 256); 696 697 for (in = out = 0; in < count; in++) { 698 gate_desc *entry = (gate_desc*)(desc->address) + in; 699 700 if (cvt_gate_to_trap(in, entry, &traps[out])) 701 out++; 702 } 703 traps[out].address = 0; 704 } 705 706 void xen_copy_trap_info(struct trap_info *traps) 707 { 708 const struct desc_ptr *desc = &__get_cpu_var(idt_desc); 709 710 xen_convert_trap_info(desc, traps); 711 } 712 713 /* Load a new IDT into Xen. In principle this can be per-CPU, so we 714 hold a spinlock to protect the static traps[] array (static because 715 it avoids allocation, and saves stack space). */ 716 static void xen_load_idt(const struct desc_ptr *desc) 717 { 718 static DEFINE_SPINLOCK(lock); 719 static struct trap_info traps[257]; 720 721 trace_xen_cpu_load_idt(desc); 722 723 spin_lock(&lock); 724 725 __get_cpu_var(idt_desc) = *desc; 726 727 xen_convert_trap_info(desc, traps); 728 729 xen_mc_flush(); 730 if (HYPERVISOR_set_trap_table(traps)) 731 BUG(); 732 733 spin_unlock(&lock); 734 } 735 736 /* Write a GDT descriptor entry. Ignore LDT descriptors, since 737 they're handled differently. */ 738 static void xen_write_gdt_entry(struct desc_struct *dt, int entry, 739 const void *desc, int type) 740 { 741 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); 742 743 preempt_disable(); 744 745 switch (type) { 746 case DESC_LDT: 747 case DESC_TSS: 748 /* ignore */ 749 break; 750 751 default: { 752 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]); 753 754 xen_mc_flush(); 755 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) 756 BUG(); 757 } 758 759 } 760 761 preempt_enable(); 762 } 763 764 /* 765 * Version of write_gdt_entry for use at early boot-time needed to 766 * update an entry as simply as possible. 767 */ 768 static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry, 769 const void *desc, int type) 770 { 771 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type); 772 773 switch (type) { 774 case DESC_LDT: 775 case DESC_TSS: 776 /* ignore */ 777 break; 778 779 default: { 780 xmaddr_t maddr = virt_to_machine(&dt[entry]); 781 782 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc)) 783 dt[entry] = *(struct desc_struct *)desc; 784 } 785 786 } 787 } 788 789 static void xen_load_sp0(struct tss_struct *tss, 790 struct thread_struct *thread) 791 { 792 struct multicall_space mcs; 793 794 mcs = xen_mc_entry(0); 795 MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0); 796 xen_mc_issue(PARAVIRT_LAZY_CPU); 797 } 798 799 static void xen_set_iopl_mask(unsigned mask) 800 { 801 struct physdev_set_iopl set_iopl; 802 803 /* Force the change at ring 0. */ 804 set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3; 805 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); 806 } 807 808 static void xen_io_delay(void) 809 { 810 } 811 812 #ifdef CONFIG_X86_LOCAL_APIC 813 static unsigned long xen_set_apic_id(unsigned int x) 814 { 815 WARN_ON(1); 816 return x; 817 } 818 static unsigned int xen_get_apic_id(unsigned long x) 819 { 820 return ((x)>>24) & 0xFFu; 821 } 822 static u32 xen_apic_read(u32 reg) 823 { 824 struct xen_platform_op op = { 825 .cmd = XENPF_get_cpuinfo, 826 .interface_version = XENPF_INTERFACE_VERSION, 827 .u.pcpu_info.xen_cpuid = 0, 828 }; 829 int ret = 0; 830 831 /* Shouldn't need this as APIC is turned off for PV, and we only 832 * get called on the bootup processor. But just in case. */ 833 if (!xen_initial_domain() || smp_processor_id()) 834 return 0; 835 836 if (reg == APIC_LVR) 837 return 0x10; 838 839 if (reg != APIC_ID) 840 return 0; 841 842 ret = HYPERVISOR_dom0_op(&op); 843 if (ret) 844 return 0; 845 846 return op.u.pcpu_info.apic_id << 24; 847 } 848 849 static void xen_apic_write(u32 reg, u32 val) 850 { 851 /* Warn to see if there's any stray references */ 852 WARN_ON(1); 853 } 854 855 static u64 xen_apic_icr_read(void) 856 { 857 return 0; 858 } 859 860 static void xen_apic_icr_write(u32 low, u32 id) 861 { 862 /* Warn to see if there's any stray references */ 863 WARN_ON(1); 864 } 865 866 static void xen_apic_wait_icr_idle(void) 867 { 868 return; 869 } 870 871 static u32 xen_safe_apic_wait_icr_idle(void) 872 { 873 return 0; 874 } 875 876 static void set_xen_basic_apic_ops(void) 877 { 878 apic->read = xen_apic_read; 879 apic->write = xen_apic_write; 880 apic->icr_read = xen_apic_icr_read; 881 apic->icr_write = xen_apic_icr_write; 882 apic->wait_icr_idle = xen_apic_wait_icr_idle; 883 apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle; 884 apic->set_apic_id = xen_set_apic_id; 885 apic->get_apic_id = xen_get_apic_id; 886 } 887 888 #endif 889 890 static void xen_clts(void) 891 { 892 struct multicall_space mcs; 893 894 mcs = xen_mc_entry(0); 895 896 MULTI_fpu_taskswitch(mcs.mc, 0); 897 898 xen_mc_issue(PARAVIRT_LAZY_CPU); 899 } 900 901 static DEFINE_PER_CPU(unsigned long, xen_cr0_value); 902 903 static unsigned long xen_read_cr0(void) 904 { 905 unsigned long cr0 = this_cpu_read(xen_cr0_value); 906 907 if (unlikely(cr0 == 0)) { 908 cr0 = native_read_cr0(); 909 this_cpu_write(xen_cr0_value, cr0); 910 } 911 912 return cr0; 913 } 914 915 static void xen_write_cr0(unsigned long cr0) 916 { 917 struct multicall_space mcs; 918 919 this_cpu_write(xen_cr0_value, cr0); 920 921 /* Only pay attention to cr0.TS; everything else is 922 ignored. */ 923 mcs = xen_mc_entry(0); 924 925 MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0); 926 927 xen_mc_issue(PARAVIRT_LAZY_CPU); 928 } 929 930 static void xen_write_cr4(unsigned long cr4) 931 { 932 cr4 &= ~X86_CR4_PGE; 933 cr4 &= ~X86_CR4_PSE; 934 935 native_write_cr4(cr4); 936 } 937 938 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) 939 { 940 int ret; 941 942 ret = 0; 943 944 switch (msr) { 945 #ifdef CONFIG_X86_64 946 unsigned which; 947 u64 base; 948 949 case MSR_FS_BASE: which = SEGBASE_FS; goto set; 950 case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set; 951 case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set; 952 953 set: 954 base = ((u64)high << 32) | low; 955 if (HYPERVISOR_set_segment_base(which, base) != 0) 956 ret = -EIO; 957 break; 958 #endif 959 960 case MSR_STAR: 961 case MSR_CSTAR: 962 case MSR_LSTAR: 963 case MSR_SYSCALL_MASK: 964 case MSR_IA32_SYSENTER_CS: 965 case MSR_IA32_SYSENTER_ESP: 966 case MSR_IA32_SYSENTER_EIP: 967 /* Fast syscall setup is all done in hypercalls, so 968 these are all ignored. Stub them out here to stop 969 Xen console noise. */ 970 break; 971 972 case MSR_IA32_CR_PAT: 973 if (smp_processor_id() == 0) 974 xen_set_pat(((u64)high << 32) | low); 975 break; 976 977 default: 978 ret = native_write_msr_safe(msr, low, high); 979 } 980 981 return ret; 982 } 983 984 void xen_setup_shared_info(void) 985 { 986 if (!xen_feature(XENFEAT_auto_translated_physmap)) { 987 set_fixmap(FIX_PARAVIRT_BOOTMAP, 988 xen_start_info->shared_info); 989 990 HYPERVISOR_shared_info = 991 (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP); 992 } else 993 HYPERVISOR_shared_info = 994 (struct shared_info *)__va(xen_start_info->shared_info); 995 996 #ifndef CONFIG_SMP 997 /* In UP this is as good a place as any to set up shared info */ 998 xen_setup_vcpu_info_placement(); 999 #endif 1000 1001 xen_setup_mfn_list_list(); 1002 } 1003 1004 /* This is called once we have the cpu_possible_mask */ 1005 void xen_setup_vcpu_info_placement(void) 1006 { 1007 int cpu; 1008 1009 for_each_possible_cpu(cpu) 1010 xen_vcpu_setup(cpu); 1011 1012 /* xen_vcpu_setup managed to place the vcpu_info within the 1013 percpu area for all cpus, so make use of it */ 1014 if (have_vcpu_info_placement) { 1015 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct); 1016 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct); 1017 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct); 1018 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct); 1019 pv_mmu_ops.read_cr2 = xen_read_cr2_direct; 1020 } 1021 } 1022 1023 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf, 1024 unsigned long addr, unsigned len) 1025 { 1026 char *start, *end, *reloc; 1027 unsigned ret; 1028 1029 start = end = reloc = NULL; 1030 1031 #define SITE(op, x) \ 1032 case PARAVIRT_PATCH(op.x): \ 1033 if (have_vcpu_info_placement) { \ 1034 start = (char *)xen_##x##_direct; \ 1035 end = xen_##x##_direct_end; \ 1036 reloc = xen_##x##_direct_reloc; \ 1037 } \ 1038 goto patch_site 1039 1040 switch (type) { 1041 SITE(pv_irq_ops, irq_enable); 1042 SITE(pv_irq_ops, irq_disable); 1043 SITE(pv_irq_ops, save_fl); 1044 SITE(pv_irq_ops, restore_fl); 1045 #undef SITE 1046 1047 patch_site: 1048 if (start == NULL || (end-start) > len) 1049 goto default_patch; 1050 1051 ret = paravirt_patch_insns(insnbuf, len, start, end); 1052 1053 /* Note: because reloc is assigned from something that 1054 appears to be an array, gcc assumes it's non-null, 1055 but doesn't know its relationship with start and 1056 end. */ 1057 if (reloc > start && reloc < end) { 1058 int reloc_off = reloc - start; 1059 long *relocp = (long *)(insnbuf + reloc_off); 1060 long delta = start - (char *)addr; 1061 1062 *relocp += delta; 1063 } 1064 break; 1065 1066 default_patch: 1067 default: 1068 ret = paravirt_patch_default(type, clobbers, insnbuf, 1069 addr, len); 1070 break; 1071 } 1072 1073 return ret; 1074 } 1075 1076 static const struct pv_info xen_info __initconst = { 1077 .paravirt_enabled = 1, 1078 .shared_kernel_pmd = 0, 1079 1080 #ifdef CONFIG_X86_64 1081 .extra_user_64bit_cs = FLAT_USER_CS64, 1082 #endif 1083 1084 .name = "Xen", 1085 }; 1086 1087 static const struct pv_init_ops xen_init_ops __initconst = { 1088 .patch = xen_patch, 1089 }; 1090 1091 static const struct pv_cpu_ops xen_cpu_ops __initconst = { 1092 .cpuid = xen_cpuid, 1093 1094 .set_debugreg = xen_set_debugreg, 1095 .get_debugreg = xen_get_debugreg, 1096 1097 .clts = xen_clts, 1098 1099 .read_cr0 = xen_read_cr0, 1100 .write_cr0 = xen_write_cr0, 1101 1102 .read_cr4 = native_read_cr4, 1103 .read_cr4_safe = native_read_cr4_safe, 1104 .write_cr4 = xen_write_cr4, 1105 1106 .wbinvd = native_wbinvd, 1107 1108 .read_msr = native_read_msr_safe, 1109 .write_msr = xen_write_msr_safe, 1110 .read_tsc = native_read_tsc, 1111 .read_pmc = native_read_pmc, 1112 1113 .iret = xen_iret, 1114 .irq_enable_sysexit = xen_sysexit, 1115 #ifdef CONFIG_X86_64 1116 .usergs_sysret32 = xen_sysret32, 1117 .usergs_sysret64 = xen_sysret64, 1118 #endif 1119 1120 .load_tr_desc = paravirt_nop, 1121 .set_ldt = xen_set_ldt, 1122 .load_gdt = xen_load_gdt, 1123 .load_idt = xen_load_idt, 1124 .load_tls = xen_load_tls, 1125 #ifdef CONFIG_X86_64 1126 .load_gs_index = xen_load_gs_index, 1127 #endif 1128 1129 .alloc_ldt = xen_alloc_ldt, 1130 .free_ldt = xen_free_ldt, 1131 1132 .store_gdt = native_store_gdt, 1133 .store_idt = native_store_idt, 1134 .store_tr = xen_store_tr, 1135 1136 .write_ldt_entry = xen_write_ldt_entry, 1137 .write_gdt_entry = xen_write_gdt_entry, 1138 .write_idt_entry = xen_write_idt_entry, 1139 .load_sp0 = xen_load_sp0, 1140 1141 .set_iopl_mask = xen_set_iopl_mask, 1142 .io_delay = xen_io_delay, 1143 1144 /* Xen takes care of %gs when switching to usermode for us */ 1145 .swapgs = paravirt_nop, 1146 1147 .start_context_switch = paravirt_start_context_switch, 1148 .end_context_switch = xen_end_context_switch, 1149 }; 1150 1151 static const struct pv_apic_ops xen_apic_ops __initconst = { 1152 #ifdef CONFIG_X86_LOCAL_APIC 1153 .startup_ipi_hook = paravirt_nop, 1154 #endif 1155 }; 1156 1157 static void xen_reboot(int reason) 1158 { 1159 struct sched_shutdown r = { .reason = reason }; 1160 1161 if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r)) 1162 BUG(); 1163 } 1164 1165 static void xen_restart(char *msg) 1166 { 1167 xen_reboot(SHUTDOWN_reboot); 1168 } 1169 1170 static void xen_emergency_restart(void) 1171 { 1172 xen_reboot(SHUTDOWN_reboot); 1173 } 1174 1175 static void xen_machine_halt(void) 1176 { 1177 xen_reboot(SHUTDOWN_poweroff); 1178 } 1179 1180 static void xen_machine_power_off(void) 1181 { 1182 if (pm_power_off) 1183 pm_power_off(); 1184 xen_reboot(SHUTDOWN_poweroff); 1185 } 1186 1187 static void xen_crash_shutdown(struct pt_regs *regs) 1188 { 1189 xen_reboot(SHUTDOWN_crash); 1190 } 1191 1192 static int 1193 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr) 1194 { 1195 xen_reboot(SHUTDOWN_crash); 1196 return NOTIFY_DONE; 1197 } 1198 1199 static struct notifier_block xen_panic_block = { 1200 .notifier_call= xen_panic_event, 1201 }; 1202 1203 int xen_panic_handler_init(void) 1204 { 1205 atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block); 1206 return 0; 1207 } 1208 1209 static const struct machine_ops xen_machine_ops __initconst = { 1210 .restart = xen_restart, 1211 .halt = xen_machine_halt, 1212 .power_off = xen_machine_power_off, 1213 .shutdown = xen_machine_halt, 1214 .crash_shutdown = xen_crash_shutdown, 1215 .emergency_restart = xen_emergency_restart, 1216 }; 1217 1218 /* 1219 * Set up the GDT and segment registers for -fstack-protector. Until 1220 * we do this, we have to be careful not to call any stack-protected 1221 * function, which is most of the kernel. 1222 */ 1223 static void __init xen_setup_stackprotector(void) 1224 { 1225 pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot; 1226 pv_cpu_ops.load_gdt = xen_load_gdt_boot; 1227 1228 setup_stack_canary_segment(0); 1229 switch_to_new_gdt(0); 1230 1231 pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry; 1232 pv_cpu_ops.load_gdt = xen_load_gdt; 1233 } 1234 1235 /* First C function to be called on Xen boot */ 1236 asmlinkage void __init xen_start_kernel(void) 1237 { 1238 struct physdev_set_iopl set_iopl; 1239 int rc; 1240 pgd_t *pgd; 1241 1242 if (!xen_start_info) 1243 return; 1244 1245 xen_domain_type = XEN_PV_DOMAIN; 1246 1247 xen_setup_machphys_mapping(); 1248 1249 /* Install Xen paravirt ops */ 1250 pv_info = xen_info; 1251 pv_init_ops = xen_init_ops; 1252 pv_cpu_ops = xen_cpu_ops; 1253 pv_apic_ops = xen_apic_ops; 1254 1255 x86_init.resources.memory_setup = xen_memory_setup; 1256 x86_init.oem.arch_setup = xen_arch_setup; 1257 x86_init.oem.banner = xen_banner; 1258 1259 xen_init_time_ops(); 1260 1261 /* 1262 * Set up some pagetable state before starting to set any ptes. 1263 */ 1264 1265 xen_init_mmu_ops(); 1266 1267 /* Prevent unwanted bits from being set in PTEs. */ 1268 __supported_pte_mask &= ~_PAGE_GLOBAL; 1269 #if 0 1270 if (!xen_initial_domain()) 1271 #endif 1272 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); 1273 1274 __supported_pte_mask |= _PAGE_IOMAP; 1275 1276 /* 1277 * Prevent page tables from being allocated in highmem, even 1278 * if CONFIG_HIGHPTE is enabled. 1279 */ 1280 __userpte_alloc_gfp &= ~__GFP_HIGHMEM; 1281 1282 /* Work out if we support NX */ 1283 x86_configure_nx(); 1284 1285 xen_setup_features(); 1286 1287 /* Get mfn list */ 1288 if (!xen_feature(XENFEAT_auto_translated_physmap)) 1289 xen_build_dynamic_phys_to_machine(); 1290 1291 /* 1292 * Set up kernel GDT and segment registers, mainly so that 1293 * -fstack-protector code can be executed. 1294 */ 1295 xen_setup_stackprotector(); 1296 1297 xen_init_irq_ops(); 1298 xen_init_cpuid_mask(); 1299 1300 #ifdef CONFIG_X86_LOCAL_APIC 1301 /* 1302 * set up the basic apic ops. 1303 */ 1304 set_xen_basic_apic_ops(); 1305 #endif 1306 1307 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) { 1308 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start; 1309 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit; 1310 } 1311 1312 machine_ops = xen_machine_ops; 1313 1314 /* 1315 * The only reliable way to retain the initial address of the 1316 * percpu gdt_page is to remember it here, so we can go and 1317 * mark it RW later, when the initial percpu area is freed. 1318 */ 1319 xen_initial_gdt = &per_cpu(gdt_page, 0); 1320 1321 xen_smp_init(); 1322 1323 #ifdef CONFIG_ACPI_NUMA 1324 /* 1325 * The pages we from Xen are not related to machine pages, so 1326 * any NUMA information the kernel tries to get from ACPI will 1327 * be meaningless. Prevent it from trying. 1328 */ 1329 acpi_numa = -1; 1330 #endif 1331 1332 pgd = (pgd_t *)xen_start_info->pt_base; 1333 1334 /* Don't do the full vcpu_info placement stuff until we have a 1335 possible map and a non-dummy shared_info. */ 1336 per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; 1337 1338 local_irq_disable(); 1339 early_boot_irqs_disabled = true; 1340 1341 xen_raw_console_write("mapping kernel into physical memory\n"); 1342 pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages); 1343 xen_ident_map_ISA(); 1344 1345 /* Allocate and initialize top and mid mfn levels for p2m structure */ 1346 xen_build_mfn_list_list(); 1347 1348 /* keep using Xen gdt for now; no urgent need to change it */ 1349 1350 #ifdef CONFIG_X86_32 1351 pv_info.kernel_rpl = 1; 1352 if (xen_feature(XENFEAT_supervisor_mode_kernel)) 1353 pv_info.kernel_rpl = 0; 1354 #else 1355 pv_info.kernel_rpl = 0; 1356 #endif 1357 /* set the limit of our address space */ 1358 xen_reserve_top(); 1359 1360 /* We used to do this in xen_arch_setup, but that is too late on AMD 1361 * were early_cpu_init (run before ->arch_setup()) calls early_amd_init 1362 * which pokes 0xcf8 port. 1363 */ 1364 set_iopl.iopl = 1; 1365 rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); 1366 if (rc != 0) 1367 xen_raw_printk("physdev_op failed %d\n", rc); 1368 1369 #ifdef CONFIG_X86_32 1370 /* set up basic CPUID stuff */ 1371 cpu_detect(&new_cpu_data); 1372 new_cpu_data.hard_math = 1; 1373 new_cpu_data.wp_works_ok = 1; 1374 new_cpu_data.x86_capability[0] = cpuid_edx(1); 1375 #endif 1376 1377 /* Poke various useful things into boot_params */ 1378 boot_params.hdr.type_of_loader = (9 << 4) | 0; 1379 boot_params.hdr.ramdisk_image = xen_start_info->mod_start 1380 ? __pa(xen_start_info->mod_start) : 0; 1381 boot_params.hdr.ramdisk_size = xen_start_info->mod_len; 1382 boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line); 1383 1384 if (!xen_initial_domain()) { 1385 add_preferred_console("xenboot", 0, NULL); 1386 add_preferred_console("tty", 0, NULL); 1387 add_preferred_console("hvc", 0, NULL); 1388 if (pci_xen) 1389 x86_init.pci.arch_init = pci_xen_init; 1390 } else { 1391 const struct dom0_vga_console_info *info = 1392 (void *)((char *)xen_start_info + 1393 xen_start_info->console.dom0.info_off); 1394 1395 xen_init_vga(info, xen_start_info->console.dom0.info_size); 1396 xen_start_info->console.domU.mfn = 0; 1397 xen_start_info->console.domU.evtchn = 0; 1398 1399 /* Make sure ACS will be enabled */ 1400 pci_request_acs(); 1401 } 1402 #ifdef CONFIG_PCI 1403 /* PCI BIOS service won't work from a PV guest. */ 1404 pci_probe &= ~PCI_PROBE_BIOS; 1405 #endif 1406 xen_raw_console_write("about to get started...\n"); 1407 1408 xen_setup_runstate_info(0); 1409 1410 /* Start the world */ 1411 #ifdef CONFIG_X86_32 1412 i386_start_kernel(); 1413 #else 1414 x86_64_start_reservations((char *)__pa_symbol(&boot_params)); 1415 #endif 1416 } 1417 1418 static int init_hvm_pv_info(int *major, int *minor) 1419 { 1420 uint32_t eax, ebx, ecx, edx, pages, msr, base; 1421 u64 pfn; 1422 1423 base = xen_cpuid_base(); 1424 cpuid(base + 1, &eax, &ebx, &ecx, &edx); 1425 1426 *major = eax >> 16; 1427 *minor = eax & 0xffff; 1428 printk(KERN_INFO "Xen version %d.%d.\n", *major, *minor); 1429 1430 cpuid(base + 2, &pages, &msr, &ecx, &edx); 1431 1432 pfn = __pa(hypercall_page); 1433 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32)); 1434 1435 xen_setup_features(); 1436 1437 pv_info.name = "Xen HVM"; 1438 1439 xen_domain_type = XEN_HVM_DOMAIN; 1440 1441 return 0; 1442 } 1443 1444 void __ref xen_hvm_init_shared_info(void) 1445 { 1446 int cpu; 1447 struct xen_add_to_physmap xatp; 1448 static struct shared_info *shared_info_page = 0; 1449 1450 if (!shared_info_page) 1451 shared_info_page = (struct shared_info *) 1452 extend_brk(PAGE_SIZE, PAGE_SIZE); 1453 xatp.domid = DOMID_SELF; 1454 xatp.idx = 0; 1455 xatp.space = XENMAPSPACE_shared_info; 1456 xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT; 1457 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 1458 BUG(); 1459 1460 HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; 1461 1462 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info 1463 * page, we use it in the event channel upcall and in some pvclock 1464 * related functions. We don't need the vcpu_info placement 1465 * optimizations because we don't use any pv_mmu or pv_irq op on 1466 * HVM. 1467 * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is 1468 * online but xen_hvm_init_shared_info is run at resume time too and 1469 * in that case multiple vcpus might be online. */ 1470 for_each_online_cpu(cpu) { 1471 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; 1472 } 1473 } 1474 1475 #ifdef CONFIG_XEN_PVHVM 1476 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self, 1477 unsigned long action, void *hcpu) 1478 { 1479 int cpu = (long)hcpu; 1480 switch (action) { 1481 case CPU_UP_PREPARE: 1482 xen_vcpu_setup(cpu); 1483 if (xen_have_vector_callback) 1484 xen_init_lock_cpu(cpu); 1485 break; 1486 default: 1487 break; 1488 } 1489 return NOTIFY_OK; 1490 } 1491 1492 static struct notifier_block xen_hvm_cpu_notifier __cpuinitdata = { 1493 .notifier_call = xen_hvm_cpu_notify, 1494 }; 1495 1496 static void __init xen_hvm_guest_init(void) 1497 { 1498 int r; 1499 int major, minor; 1500 1501 r = init_hvm_pv_info(&major, &minor); 1502 if (r < 0) 1503 return; 1504 1505 xen_hvm_init_shared_info(); 1506 1507 if (xen_feature(XENFEAT_hvm_callback_vector)) 1508 xen_have_vector_callback = 1; 1509 xen_hvm_smp_init(); 1510 register_cpu_notifier(&xen_hvm_cpu_notifier); 1511 xen_unplug_emulated_devices(); 1512 x86_init.irqs.intr_init = xen_init_IRQ; 1513 xen_hvm_init_time_ops(); 1514 xen_hvm_init_mmu_ops(); 1515 } 1516 1517 static bool __init xen_hvm_platform(void) 1518 { 1519 if (xen_pv_domain()) 1520 return false; 1521 1522 if (!xen_cpuid_base()) 1523 return false; 1524 1525 return true; 1526 } 1527 1528 bool xen_hvm_need_lapic(void) 1529 { 1530 if (xen_pv_domain()) 1531 return false; 1532 if (!xen_hvm_domain()) 1533 return false; 1534 if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback) 1535 return false; 1536 return true; 1537 } 1538 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic); 1539 1540 const struct hypervisor_x86 x86_hyper_xen_hvm __refconst = { 1541 .name = "Xen HVM", 1542 .detect = xen_hvm_platform, 1543 .init_platform = xen_hvm_guest_init, 1544 }; 1545 EXPORT_SYMBOL(x86_hyper_xen_hvm); 1546 #endif 1547