enlighten.c 38 KB

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