Merge tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel...
[~shefty/rdma-dev.git] / arch / x86 / xen / enlighten.c
1 /*
2  * Core of Xen paravirt_ops implementation.
3  *
4  * This file contains the xen_paravirt_ops structure itself, and the
5  * implementations for:
6  * - privileged instructions
7  * - interrupt flags
8  * - segment operations
9  * - booting and setup
10  *
11  * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
12  */
13
14 #include <linux/cpu.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/smp.h>
18 #include <linux/preempt.h>
19 #include <linux/hardirq.h>
20 #include <linux/percpu.h>
21 #include <linux/delay.h>
22 #include <linux/start_kernel.h>
23 #include <linux/sched.h>
24 #include <linux/kprobes.h>
25 #include <linux/bootmem.h>
26 #include <linux/module.h>
27 #include <linux/mm.h>
28 #include <linux/page-flags.h>
29 #include <linux/highmem.h>
30 #include <linux/console.h>
31 #include <linux/pci.h>
32 #include <linux/gfp.h>
33 #include <linux/memblock.h>
34
35 #include <xen/xen.h>
36 #include <xen/interface/xen.h>
37 #include <xen/interface/version.h>
38 #include <xen/interface/physdev.h>
39 #include <xen/interface/vcpu.h>
40 #include <xen/interface/memory.h>
41 #include <xen/features.h>
42 #include <xen/page.h>
43 #include <xen/hvm.h>
44 #include <xen/hvc-console.h>
45
46 #include <asm/paravirt.h>
47 #include <asm/apic.h>
48 #include <asm/page.h>
49 #include <asm/xen/pci.h>
50 #include <asm/xen/hypercall.h>
51 #include <asm/xen/hypervisor.h>
52 #include <asm/fixmap.h>
53 #include <asm/processor.h>
54 #include <asm/proto.h>
55 #include <asm/msr-index.h>
56 #include <asm/traps.h>
57 #include <asm/setup.h>
58 #include <asm/desc.h>
59 #include <asm/pgalloc.h>
60 #include <asm/pgtable.h>
61 #include <asm/tlbflush.h>
62 #include <asm/reboot.h>
63 #include <asm/stackprotector.h>
64 #include <asm/hypervisor.h>
65 #include <asm/mwait.h>
66
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
75 #include "xen-ops.h"
76 #include "mmu.h"
77 #include "multicalls.h"
78
79 EXPORT_SYMBOL_GPL(hypercall_page);
80
81 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
82 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
83
84 enum xen_domain_type xen_domain_type = XEN_NATIVE;
85 EXPORT_SYMBOL_GPL(xen_domain_type);
86
87 unsigned long *machine_to_phys_mapping = (void *)MACH2PHYS_VIRT_START;
88 EXPORT_SYMBOL(machine_to_phys_mapping);
89 unsigned long  machine_to_phys_nr;
90 EXPORT_SYMBOL(machine_to_phys_nr);
91
92 struct start_info *xen_start_info;
93 EXPORT_SYMBOL_GPL(xen_start_info);
94
95 struct shared_info xen_dummy_shared_info;
96
97 void *xen_initial_gdt;
98
99 RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
100 __read_mostly int xen_have_vector_callback;
101 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
102
103 /*
104  * Point at some empty memory to start with. We map the real shared_info
105  * page as soon as fixmap is up and running.
106  */
107 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
108
109 /*
110  * Flag to determine whether vcpu info placement is available on all
111  * VCPUs.  We assume it is to start with, and then set it to zero on
112  * the first failure.  This is because it can succeed on some VCPUs
113  * and not others, since it can involve hypervisor memory allocation,
114  * or because the guest failed to guarantee all the appropriate
115  * constraints on all VCPUs (ie buffer can't cross a page boundary).
116  *
117  * Note that any particular CPU may be using a placed vcpu structure,
118  * but we can only optimise if the all are.
119  *
120  * 0: not available, 1: available
121  */
122 static int have_vcpu_info_placement = 1;
123
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
132 static void xen_vcpu_setup(int cpu)
133 {
134         struct vcpu_register_vcpu_info info;
135         int err;
136         struct vcpu_info *vcpup;
137
138         BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
139
140         if (cpu < MAX_VIRT_CPUS)
141                 per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
142
143         if (!have_vcpu_info_placement) {
144                 if (cpu >= MAX_VIRT_CPUS)
145                         clamp_max_cpus();
146                 return;
147         }
148
149         vcpup = &per_cpu(xen_vcpu_info, cpu);
150         info.mfn = arbitrary_virt_to_mfn(vcpup);
151         info.offset = offset_in_page(vcpup);
152
153         /* Check to see if the hypervisor will put the vcpu_info
154            structure where we want it, which allows direct access via
155            a percpu-variable. */
156         err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
157
158         if (err) {
159                 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
160                 have_vcpu_info_placement = 0;
161                 clamp_max_cpus();
162         } else {
163                 /* This cpu is using the registered vcpu info, even if
164                    later ones fail to. */
165                 per_cpu(xen_vcpu, cpu) = vcpup;
166         }
167 }
168
169 /*
170  * On restore, set the vcpu placement up again.
171  * If it fails, then we're in a bad state, since
172  * we can't back out from using it...
173  */
174 void xen_vcpu_restore(void)
175 {
176         int cpu;
177
178         for_each_online_cpu(cpu) {
179                 bool other_cpu = (cpu != smp_processor_id());
180
181                 if (other_cpu &&
182                     HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL))
183                         BUG();
184
185                 xen_setup_runstate_info(cpu);
186
187                 if (have_vcpu_info_placement)
188                         xen_vcpu_setup(cpu);
189
190                 if (other_cpu &&
191                     HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL))
192                         BUG();
193         }
194 }
195
196 static void __init xen_banner(void)
197 {
198         unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
199         struct xen_extraversion extra;
200         HYPERVISOR_xen_version(XENVER_extraversion, &extra);
201
202         printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
203                pv_info.name);
204         printk(KERN_INFO "Xen version: %d.%d%s%s\n",
205                version >> 16, version & 0xffff, extra.extraversion,
206                xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
207 }
208
209 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
210 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
211
212 static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask;
213 static __read_mostly unsigned int cpuid_leaf5_ecx_val;
214 static __read_mostly unsigned int cpuid_leaf5_edx_val;
215
216 static void xen_cpuid(unsigned int *ax, unsigned int *bx,
217                       unsigned int *cx, unsigned int *dx)
218 {
219         unsigned maskebx = ~0;
220         unsigned maskecx = ~0;
221         unsigned maskedx = ~0;
222         unsigned setecx = 0;
223         /*
224          * Mask out inconvenient features, to try and disable as many
225          * unsupported kernel subsystems as possible.
226          */
227         switch (*ax) {
228         case 1:
229                 maskecx = cpuid_leaf1_ecx_mask;
230                 setecx = cpuid_leaf1_ecx_set_mask;
231                 maskedx = cpuid_leaf1_edx_mask;
232                 break;
233
234         case CPUID_MWAIT_LEAF:
235                 /* Synthesize the values.. */
236                 *ax = 0;
237                 *bx = 0;
238                 *cx = cpuid_leaf5_ecx_val;
239                 *dx = cpuid_leaf5_edx_val;
240                 return;
241
242         case 0xb:
243                 /* Suppress extended topology stuff */
244                 maskebx = 0;
245                 break;
246         }
247
248         asm(XEN_EMULATE_PREFIX "cpuid"
249                 : "=a" (*ax),
250                   "=b" (*bx),
251                   "=c" (*cx),
252                   "=d" (*dx)
253                 : "0" (*ax), "2" (*cx));
254
255         *bx &= maskebx;
256         *cx &= maskecx;
257         *cx |= setecx;
258         *dx &= maskedx;
259
260 }
261
262 static bool __init xen_check_mwait(void)
263 {
264 #ifdef CONFIG_ACPI
265         struct xen_platform_op op = {
266                 .cmd                    = XENPF_set_processor_pminfo,
267                 .u.set_pminfo.id        = -1,
268                 .u.set_pminfo.type      = XEN_PM_PDC,
269         };
270         uint32_t buf[3];
271         unsigned int ax, bx, cx, dx;
272         unsigned int mwait_mask;
273
274         /* We need to determine whether it is OK to expose the MWAIT
275          * capability to the kernel to harvest deeper than C3 states from ACPI
276          * _CST using the processor_harvest_xen.c module. For this to work, we
277          * need to gather the MWAIT_LEAF values (which the cstate.c code
278          * checks against). The hypervisor won't expose the MWAIT flag because
279          * it would break backwards compatibility; so we will find out directly
280          * from the hardware and hypercall.
281          */
282         if (!xen_initial_domain())
283                 return false;
284
285         ax = 1;
286         cx = 0;
287
288         native_cpuid(&ax, &bx, &cx, &dx);
289
290         mwait_mask = (1 << (X86_FEATURE_EST % 32)) |
291                      (1 << (X86_FEATURE_MWAIT % 32));
292
293         if ((cx & mwait_mask) != mwait_mask)
294                 return false;
295
296         /* We need to emulate the MWAIT_LEAF and for that we need both
297          * ecx and edx. The hypercall provides only partial information.
298          */
299
300         ax = CPUID_MWAIT_LEAF;
301         bx = 0;
302         cx = 0;
303         dx = 0;
304
305         native_cpuid(&ax, &bx, &cx, &dx);
306
307         /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so,
308          * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3.
309          */
310         buf[0] = ACPI_PDC_REVISION_ID;
311         buf[1] = 1;
312         buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP);
313
314         set_xen_guest_handle(op.u.set_pminfo.pdc, buf);
315
316         if ((HYPERVISOR_dom0_op(&op) == 0) &&
317             (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) {
318                 cpuid_leaf5_ecx_val = cx;
319                 cpuid_leaf5_edx_val = dx;
320         }
321         return true;
322 #else
323         return false;
324 #endif
325 }
326 static void __init xen_init_cpuid_mask(void)
327 {
328         unsigned int ax, bx, cx, dx;
329         unsigned int xsave_mask;
330
331         cpuid_leaf1_edx_mask =
332                 ~((1 << X86_FEATURE_MCE)  |  /* disable MCE */
333                   (1 << X86_FEATURE_MCA)  |  /* disable MCA */
334                   (1 << X86_FEATURE_MTRR) |  /* disable MTRR */
335                   (1 << X86_FEATURE_ACC));   /* thermal monitoring */
336
337         if (!xen_initial_domain())
338                 cpuid_leaf1_edx_mask &=
339                         ~((1 << X86_FEATURE_APIC) |  /* disable local APIC */
340                           (1 << X86_FEATURE_ACPI));  /* disable ACPI */
341         ax = 1;
342         cx = 0;
343         xen_cpuid(&ax, &bx, &cx, &dx);
344
345         xsave_mask =
346                 (1 << (X86_FEATURE_XSAVE % 32)) |
347                 (1 << (X86_FEATURE_OSXSAVE % 32));
348
349         /* Xen will set CR4.OSXSAVE if supported and not disabled by force */
350         if ((cx & xsave_mask) != xsave_mask)
351                 cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */
352
353         if (xen_check_mwait())
354                 cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32));
355 }
356
357 static void xen_set_debugreg(int reg, unsigned long val)
358 {
359         HYPERVISOR_set_debugreg(reg, val);
360 }
361
362 static unsigned long xen_get_debugreg(int reg)
363 {
364         return HYPERVISOR_get_debugreg(reg);
365 }
366
367 static void xen_end_context_switch(struct task_struct *next)
368 {
369         xen_mc_flush();
370         paravirt_end_context_switch(next);
371 }
372
373 static unsigned long xen_store_tr(void)
374 {
375         return 0;
376 }
377
378 /*
379  * Set the page permissions for a particular virtual address.  If the
380  * address is a vmalloc mapping (or other non-linear mapping), then
381  * find the linear mapping of the page and also set its protections to
382  * match.
383  */
384 static void set_aliased_prot(void *v, pgprot_t prot)
385 {
386         int level;
387         pte_t *ptep;
388         pte_t pte;
389         unsigned long pfn;
390         struct page *page;
391
392         ptep = lookup_address((unsigned long)v, &level);
393         BUG_ON(ptep == NULL);
394
395         pfn = pte_pfn(*ptep);
396         page = pfn_to_page(pfn);
397
398         pte = pfn_pte(pfn, prot);
399
400         if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
401                 BUG();
402
403         if (!PageHighMem(page)) {
404                 void *av = __va(PFN_PHYS(pfn));
405
406                 if (av != v)
407                         if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
408                                 BUG();
409         } else
410                 kmap_flush_unused();
411 }
412
413 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
414 {
415         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
416         int i;
417
418         for(i = 0; i < entries; i += entries_per_page)
419                 set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
420 }
421
422 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
423 {
424         const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
425         int i;
426
427         for(i = 0; i < entries; i += entries_per_page)
428                 set_aliased_prot(ldt + i, PAGE_KERNEL);
429 }
430
431 static void xen_set_ldt(const void *addr, unsigned entries)
432 {
433         struct mmuext_op *op;
434         struct multicall_space mcs = xen_mc_entry(sizeof(*op));
435
436         trace_xen_cpu_set_ldt(addr, entries);
437
438         op = mcs.args;
439         op->cmd = MMUEXT_SET_LDT;
440         op->arg1.linear_addr = (unsigned long)addr;
441         op->arg2.nr_ents = entries;
442
443         MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
444
445         xen_mc_issue(PARAVIRT_LAZY_CPU);
446 }
447
448 static void xen_load_gdt(const struct desc_ptr *dtr)
449 {
450         unsigned long va = dtr->address;
451         unsigned int size = dtr->size + 1;
452         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
453         unsigned long frames[pages];
454         int f;
455
456         /*
457          * A GDT can be up to 64k in size, which corresponds to 8192
458          * 8-byte entries, or 16 4k pages..
459          */
460
461         BUG_ON(size > 65536);
462         BUG_ON(va & ~PAGE_MASK);
463
464         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
465                 int level;
466                 pte_t *ptep;
467                 unsigned long pfn, mfn;
468                 void *virt;
469
470                 /*
471                  * The GDT is per-cpu and is in the percpu data area.
472                  * That can be virtually mapped, so we need to do a
473                  * page-walk to get the underlying MFN for the
474                  * hypercall.  The page can also be in the kernel's
475                  * linear range, so we need to RO that mapping too.
476                  */
477                 ptep = lookup_address(va, &level);
478                 BUG_ON(ptep == NULL);
479
480                 pfn = pte_pfn(*ptep);
481                 mfn = pfn_to_mfn(pfn);
482                 virt = __va(PFN_PHYS(pfn));
483
484                 frames[f] = mfn;
485
486                 make_lowmem_page_readonly((void *)va);
487                 make_lowmem_page_readonly(virt);
488         }
489
490         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
491                 BUG();
492 }
493
494 /*
495  * load_gdt for early boot, when the gdt is only mapped once
496  */
497 static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
498 {
499         unsigned long va = dtr->address;
500         unsigned int size = dtr->size + 1;
501         unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
502         unsigned long frames[pages];
503         int f;
504
505         /*
506          * A GDT can be up to 64k in size, which corresponds to 8192
507          * 8-byte entries, or 16 4k pages..
508          */
509
510         BUG_ON(size > 65536);
511         BUG_ON(va & ~PAGE_MASK);
512
513         for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
514                 pte_t pte;
515                 unsigned long pfn, mfn;
516
517                 pfn = virt_to_pfn(va);
518                 mfn = pfn_to_mfn(pfn);
519
520                 pte = pfn_pte(pfn, PAGE_KERNEL_RO);
521
522                 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
523                         BUG();
524
525                 frames[f] = mfn;
526         }
527
528         if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
529                 BUG();
530 }
531
532 static void load_TLS_descriptor(struct thread_struct *t,
533                                 unsigned int cpu, unsigned int i)
534 {
535         struct desc_struct *gdt = get_cpu_gdt_table(cpu);
536         xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
537         struct multicall_space mc = __xen_mc_entry(0);
538
539         MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
540 }
541
542 static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
543 {
544         /*
545          * XXX sleazy hack: If we're being called in a lazy-cpu zone
546          * and lazy gs handling is enabled, it means we're in a
547          * context switch, and %gs has just been saved.  This means we
548          * can zero it out to prevent faults on exit from the
549          * hypervisor if the next process has no %gs.  Either way, it
550          * has been saved, and the new value will get loaded properly.
551          * This will go away as soon as Xen has been modified to not
552          * save/restore %gs for normal hypercalls.
553          *
554          * On x86_64, this hack is not used for %gs, because gs points
555          * to KERNEL_GS_BASE (and uses it for PDA references), so we
556          * must not zero %gs on x86_64
557          *
558          * For x86_64, we need to zero %fs, otherwise we may get an
559          * exception between the new %fs descriptor being loaded and
560          * %fs being effectively cleared at __switch_to().
561          */
562         if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
563 #ifdef CONFIG_X86_32
564                 lazy_load_gs(0);
565 #else
566                 loadsegment(fs, 0);
567 #endif
568         }
569
570         xen_mc_batch();
571
572         load_TLS_descriptor(t, cpu, 0);
573         load_TLS_descriptor(t, cpu, 1);
574         load_TLS_descriptor(t, cpu, 2);
575
576         xen_mc_issue(PARAVIRT_LAZY_CPU);
577 }
578
579 #ifdef CONFIG_X86_64
580 static void xen_load_gs_index(unsigned int idx)
581 {
582         if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
583                 BUG();
584 }
585 #endif
586
587 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
588                                 const void *ptr)
589 {
590         xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
591         u64 entry = *(u64 *)ptr;
592
593         trace_xen_cpu_write_ldt_entry(dt, entrynum, entry);
594
595         preempt_disable();
596
597         xen_mc_flush();
598         if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
599                 BUG();
600
601         preempt_enable();
602 }
603
604 static int cvt_gate_to_trap(int vector, const gate_desc *val,
605                             struct trap_info *info)
606 {
607         unsigned long addr;
608
609         if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
610                 return 0;
611
612         info->vector = vector;
613
614         addr = gate_offset(*val);
615 #ifdef CONFIG_X86_64
616         /*
617          * Look for known traps using IST, and substitute them
618          * appropriately.  The debugger ones are the only ones we care
619          * about.  Xen will handle faults like double_fault and
620          * machine_check, so we should never see them.  Warn if
621          * there's an unexpected IST-using fault handler.
622          */
623         if (addr == (unsigned long)debug)
624                 addr = (unsigned long)xen_debug;
625         else if (addr == (unsigned long)int3)
626                 addr = (unsigned long)xen_int3;
627         else if (addr == (unsigned long)stack_segment)
628                 addr = (unsigned long)xen_stack_segment;
629         else if (addr == (unsigned long)double_fault ||
630                  addr == (unsigned long)nmi) {
631                 /* Don't need to handle these */
632                 return 0;
633 #ifdef CONFIG_X86_MCE
634         } else if (addr == (unsigned long)machine_check) {
635                 return 0;
636 #endif
637         } else {
638                 /* Some other trap using IST? */
639                 if (WARN_ON(val->ist != 0))
640                         return 0;
641         }
642 #endif  /* CONFIG_X86_64 */
643         info->address = addr;
644
645         info->cs = gate_segment(*val);
646         info->flags = val->dpl;
647         /* interrupt gates clear IF */
648         if (val->type == GATE_INTERRUPT)
649                 info->flags |= 1 << 2;
650
651         return 1;
652 }
653
654 /* Locations of each CPU's IDT */
655 static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
656
657 /* Set an IDT entry.  If the entry is part of the current IDT, then
658    also update Xen. */
659 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
660 {
661         unsigned long p = (unsigned long)&dt[entrynum];
662         unsigned long start, end;
663
664         trace_xen_cpu_write_idt_entry(dt, entrynum, g);
665
666         preempt_disable();
667
668         start = __this_cpu_read(idt_desc.address);
669         end = start + __this_cpu_read(idt_desc.size) + 1;
670
671         xen_mc_flush();
672
673         native_write_idt_entry(dt, entrynum, g);
674
675         if (p >= start && (p + 8) <= end) {
676                 struct trap_info info[2];
677
678                 info[1].address = 0;
679
680                 if (cvt_gate_to_trap(entrynum, g, &info[0]))
681                         if (HYPERVISOR_set_trap_table(info))
682                                 BUG();
683         }
684
685         preempt_enable();
686 }
687
688 static void xen_convert_trap_info(const struct desc_ptr *desc,
689                                   struct trap_info *traps)
690 {
691         unsigned in, out, count;
692
693         count = (desc->size+1) / sizeof(gate_desc);
694         BUG_ON(count > 256);
695
696         for (in = out = 0; in < count; in++) {
697                 gate_desc *entry = (gate_desc*)(desc->address) + in;
698
699                 if (cvt_gate_to_trap(in, entry, &traps[out]))
700                         out++;
701         }
702         traps[out].address = 0;
703 }
704
705 void xen_copy_trap_info(struct trap_info *traps)
706 {
707         const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
708
709         xen_convert_trap_info(desc, traps);
710 }
711
712 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
713    hold a spinlock to protect the static traps[] array (static because
714    it avoids allocation, and saves stack space). */
715 static void xen_load_idt(const struct desc_ptr *desc)
716 {
717         static DEFINE_SPINLOCK(lock);
718         static struct trap_info traps[257];
719
720         trace_xen_cpu_load_idt(desc);
721
722         spin_lock(&lock);
723
724         __get_cpu_var(idt_desc) = *desc;
725
726         xen_convert_trap_info(desc, traps);
727
728         xen_mc_flush();
729         if (HYPERVISOR_set_trap_table(traps))
730                 BUG();
731
732         spin_unlock(&lock);
733 }
734
735 /* Write a GDT descriptor entry.  Ignore LDT descriptors, since
736    they're handled differently. */
737 static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
738                                 const void *desc, int type)
739 {
740         trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
741
742         preempt_disable();
743
744         switch (type) {
745         case DESC_LDT:
746         case DESC_TSS:
747                 /* ignore */
748                 break;
749
750         default: {
751                 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
752
753                 xen_mc_flush();
754                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
755                         BUG();
756         }
757
758         }
759
760         preempt_enable();
761 }
762
763 /*
764  * Version of write_gdt_entry for use at early boot-time needed to
765  * update an entry as simply as possible.
766  */
767 static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
768                                             const void *desc, int type)
769 {
770         trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
771
772         switch (type) {
773         case DESC_LDT:
774         case DESC_TSS:
775                 /* ignore */
776                 break;
777
778         default: {
779                 xmaddr_t maddr = virt_to_machine(&dt[entry]);
780
781                 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
782                         dt[entry] = *(struct desc_struct *)desc;
783         }
784
785         }
786 }
787
788 static void xen_load_sp0(struct tss_struct *tss,
789                          struct thread_struct *thread)
790 {
791         struct multicall_space mcs;
792
793         mcs = xen_mc_entry(0);
794         MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
795         xen_mc_issue(PARAVIRT_LAZY_CPU);
796 }
797
798 static void xen_set_iopl_mask(unsigned mask)
799 {
800         struct physdev_set_iopl set_iopl;
801
802         /* Force the change at ring 0. */
803         set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
804         HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
805 }
806
807 static void xen_io_delay(void)
808 {
809 }
810
811 #ifdef CONFIG_X86_LOCAL_APIC
812 static u32 xen_apic_read(u32 reg)
813 {
814         return 0;
815 }
816
817 static void xen_apic_write(u32 reg, u32 val)
818 {
819         /* Warn to see if there's any stray references */
820         WARN_ON(1);
821 }
822
823 static u64 xen_apic_icr_read(void)
824 {
825         return 0;
826 }
827
828 static void xen_apic_icr_write(u32 low, u32 id)
829 {
830         /* Warn to see if there's any stray references */
831         WARN_ON(1);
832 }
833
834 static void xen_apic_wait_icr_idle(void)
835 {
836         return;
837 }
838
839 static u32 xen_safe_apic_wait_icr_idle(void)
840 {
841         return 0;
842 }
843
844 static void set_xen_basic_apic_ops(void)
845 {
846         apic->read = xen_apic_read;
847         apic->write = xen_apic_write;
848         apic->icr_read = xen_apic_icr_read;
849         apic->icr_write = xen_apic_icr_write;
850         apic->wait_icr_idle = xen_apic_wait_icr_idle;
851         apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
852 }
853
854 #endif
855
856 static void xen_clts(void)
857 {
858         struct multicall_space mcs;
859
860         mcs = xen_mc_entry(0);
861
862         MULTI_fpu_taskswitch(mcs.mc, 0);
863
864         xen_mc_issue(PARAVIRT_LAZY_CPU);
865 }
866
867 static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
868
869 static unsigned long xen_read_cr0(void)
870 {
871         unsigned long cr0 = this_cpu_read(xen_cr0_value);
872
873         if (unlikely(cr0 == 0)) {
874                 cr0 = native_read_cr0();
875                 this_cpu_write(xen_cr0_value, cr0);
876         }
877
878         return cr0;
879 }
880
881 static void xen_write_cr0(unsigned long cr0)
882 {
883         struct multicall_space mcs;
884
885         this_cpu_write(xen_cr0_value, cr0);
886
887         /* Only pay attention to cr0.TS; everything else is
888            ignored. */
889         mcs = xen_mc_entry(0);
890
891         MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
892
893         xen_mc_issue(PARAVIRT_LAZY_CPU);
894 }
895
896 static void xen_write_cr4(unsigned long cr4)
897 {
898         cr4 &= ~X86_CR4_PGE;
899         cr4 &= ~X86_CR4_PSE;
900
901         native_write_cr4(cr4);
902 }
903
904 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
905 {
906         int ret;
907
908         ret = 0;
909
910         switch (msr) {
911 #ifdef CONFIG_X86_64
912                 unsigned which;
913                 u64 base;
914
915         case MSR_FS_BASE:               which = SEGBASE_FS; goto set;
916         case MSR_KERNEL_GS_BASE:        which = SEGBASE_GS_USER; goto set;
917         case MSR_GS_BASE:               which = SEGBASE_GS_KERNEL; goto set;
918
919         set:
920                 base = ((u64)high << 32) | low;
921                 if (HYPERVISOR_set_segment_base(which, base) != 0)
922                         ret = -EIO;
923                 break;
924 #endif
925
926         case MSR_STAR:
927         case MSR_CSTAR:
928         case MSR_LSTAR:
929         case MSR_SYSCALL_MASK:
930         case MSR_IA32_SYSENTER_CS:
931         case MSR_IA32_SYSENTER_ESP:
932         case MSR_IA32_SYSENTER_EIP:
933                 /* Fast syscall setup is all done in hypercalls, so
934                    these are all ignored.  Stub them out here to stop
935                    Xen console noise. */
936                 break;
937
938         case MSR_IA32_CR_PAT:
939                 if (smp_processor_id() == 0)
940                         xen_set_pat(((u64)high << 32) | low);
941                 break;
942
943         default:
944                 ret = native_write_msr_safe(msr, low, high);
945         }
946
947         return ret;
948 }
949
950 void xen_setup_shared_info(void)
951 {
952         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
953                 set_fixmap(FIX_PARAVIRT_BOOTMAP,
954                            xen_start_info->shared_info);
955
956                 HYPERVISOR_shared_info =
957                         (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
958         } else
959                 HYPERVISOR_shared_info =
960                         (struct shared_info *)__va(xen_start_info->shared_info);
961
962 #ifndef CONFIG_SMP
963         /* In UP this is as good a place as any to set up shared info */
964         xen_setup_vcpu_info_placement();
965 #endif
966
967         xen_setup_mfn_list_list();
968 }
969
970 /* This is called once we have the cpu_possible_map */
971 void xen_setup_vcpu_info_placement(void)
972 {
973         int cpu;
974
975         for_each_possible_cpu(cpu)
976                 xen_vcpu_setup(cpu);
977
978         /* xen_vcpu_setup managed to place the vcpu_info within the
979            percpu area for all cpus, so make use of it */
980         if (have_vcpu_info_placement) {
981                 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
982                 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
983                 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
984                 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
985                 pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
986         }
987 }
988
989 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
990                           unsigned long addr, unsigned len)
991 {
992         char *start, *end, *reloc;
993         unsigned ret;
994
995         start = end = reloc = NULL;
996
997 #define SITE(op, x)                                                     \
998         case PARAVIRT_PATCH(op.x):                                      \
999         if (have_vcpu_info_placement) {                                 \
1000                 start = (char *)xen_##x##_direct;                       \
1001                 end = xen_##x##_direct_end;                             \
1002                 reloc = xen_##x##_direct_reloc;                         \
1003         }                                                               \
1004         goto patch_site
1005
1006         switch (type) {
1007                 SITE(pv_irq_ops, irq_enable);
1008                 SITE(pv_irq_ops, irq_disable);
1009                 SITE(pv_irq_ops, save_fl);
1010                 SITE(pv_irq_ops, restore_fl);
1011 #undef SITE
1012
1013         patch_site:
1014                 if (start == NULL || (end-start) > len)
1015                         goto default_patch;
1016
1017                 ret = paravirt_patch_insns(insnbuf, len, start, end);
1018
1019                 /* Note: because reloc is assigned from something that
1020                    appears to be an array, gcc assumes it's non-null,
1021                    but doesn't know its relationship with start and
1022                    end. */
1023                 if (reloc > start && reloc < end) {
1024                         int reloc_off = reloc - start;
1025                         long *relocp = (long *)(insnbuf + reloc_off);
1026                         long delta = start - (char *)addr;
1027
1028                         *relocp += delta;
1029                 }
1030                 break;
1031
1032         default_patch:
1033         default:
1034                 ret = paravirt_patch_default(type, clobbers, insnbuf,
1035                                              addr, len);
1036                 break;
1037         }
1038
1039         return ret;
1040 }
1041
1042 static const struct pv_info xen_info __initconst = {
1043         .paravirt_enabled = 1,
1044         .shared_kernel_pmd = 0,
1045
1046 #ifdef CONFIG_X86_64
1047         .extra_user_64bit_cs = FLAT_USER_CS64,
1048 #endif
1049
1050         .name = "Xen",
1051 };
1052
1053 static const struct pv_init_ops xen_init_ops __initconst = {
1054         .patch = xen_patch,
1055 };
1056
1057 static const struct pv_cpu_ops xen_cpu_ops __initconst = {
1058         .cpuid = xen_cpuid,
1059
1060         .set_debugreg = xen_set_debugreg,
1061         .get_debugreg = xen_get_debugreg,
1062
1063         .clts = xen_clts,
1064
1065         .read_cr0 = xen_read_cr0,
1066         .write_cr0 = xen_write_cr0,
1067
1068         .read_cr4 = native_read_cr4,
1069         .read_cr4_safe = native_read_cr4_safe,
1070         .write_cr4 = xen_write_cr4,
1071
1072         .wbinvd = native_wbinvd,
1073
1074         .read_msr = native_read_msr_safe,
1075         .write_msr = xen_write_msr_safe,
1076         .read_tsc = native_read_tsc,
1077         .read_pmc = native_read_pmc,
1078
1079         .iret = xen_iret,
1080         .irq_enable_sysexit = xen_sysexit,
1081 #ifdef CONFIG_X86_64
1082         .usergs_sysret32 = xen_sysret32,
1083         .usergs_sysret64 = xen_sysret64,
1084 #endif
1085
1086         .load_tr_desc = paravirt_nop,
1087         .set_ldt = xen_set_ldt,
1088         .load_gdt = xen_load_gdt,
1089         .load_idt = xen_load_idt,
1090         .load_tls = xen_load_tls,
1091 #ifdef CONFIG_X86_64
1092         .load_gs_index = xen_load_gs_index,
1093 #endif
1094
1095         .alloc_ldt = xen_alloc_ldt,
1096         .free_ldt = xen_free_ldt,
1097
1098         .store_gdt = native_store_gdt,
1099         .store_idt = native_store_idt,
1100         .store_tr = xen_store_tr,
1101
1102         .write_ldt_entry = xen_write_ldt_entry,
1103         .write_gdt_entry = xen_write_gdt_entry,
1104         .write_idt_entry = xen_write_idt_entry,
1105         .load_sp0 = xen_load_sp0,
1106
1107         .set_iopl_mask = xen_set_iopl_mask,
1108         .io_delay = xen_io_delay,
1109
1110         /* Xen takes care of %gs when switching to usermode for us */
1111         .swapgs = paravirt_nop,
1112
1113         .start_context_switch = paravirt_start_context_switch,
1114         .end_context_switch = xen_end_context_switch,
1115 };
1116
1117 static const struct pv_apic_ops xen_apic_ops __initconst = {
1118 #ifdef CONFIG_X86_LOCAL_APIC
1119         .startup_ipi_hook = paravirt_nop,
1120 #endif
1121 };
1122
1123 static void xen_reboot(int reason)
1124 {
1125         struct sched_shutdown r = { .reason = reason };
1126
1127         if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
1128                 BUG();
1129 }
1130
1131 static void xen_restart(char *msg)
1132 {
1133         xen_reboot(SHUTDOWN_reboot);
1134 }
1135
1136 static void xen_emergency_restart(void)
1137 {
1138         xen_reboot(SHUTDOWN_reboot);
1139 }
1140
1141 static void xen_machine_halt(void)
1142 {
1143         xen_reboot(SHUTDOWN_poweroff);
1144 }
1145
1146 static void xen_machine_power_off(void)
1147 {
1148         if (pm_power_off)
1149                 pm_power_off();
1150         xen_reboot(SHUTDOWN_poweroff);
1151 }
1152
1153 static void xen_crash_shutdown(struct pt_regs *regs)
1154 {
1155         xen_reboot(SHUTDOWN_crash);
1156 }
1157
1158 static int
1159 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
1160 {
1161         xen_reboot(SHUTDOWN_crash);
1162         return NOTIFY_DONE;
1163 }
1164
1165 static struct notifier_block xen_panic_block = {
1166         .notifier_call= xen_panic_event,
1167 };
1168
1169 int xen_panic_handler_init(void)
1170 {
1171         atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
1172         return 0;
1173 }
1174
1175 static const struct machine_ops xen_machine_ops __initconst = {
1176         .restart = xen_restart,
1177         .halt = xen_machine_halt,
1178         .power_off = xen_machine_power_off,
1179         .shutdown = xen_machine_halt,
1180         .crash_shutdown = xen_crash_shutdown,
1181         .emergency_restart = xen_emergency_restart,
1182 };
1183
1184 /*
1185  * Set up the GDT and segment registers for -fstack-protector.  Until
1186  * we do this, we have to be careful not to call any stack-protected
1187  * function, which is most of the kernel.
1188  */
1189 static void __init xen_setup_stackprotector(void)
1190 {
1191         pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot;
1192         pv_cpu_ops.load_gdt = xen_load_gdt_boot;
1193
1194         setup_stack_canary_segment(0);
1195         switch_to_new_gdt(0);
1196
1197         pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry;
1198         pv_cpu_ops.load_gdt = xen_load_gdt;
1199 }
1200
1201 /* First C function to be called on Xen boot */
1202 asmlinkage void __init xen_start_kernel(void)
1203 {
1204         struct physdev_set_iopl set_iopl;
1205         int rc;
1206         pgd_t *pgd;
1207
1208         if (!xen_start_info)
1209                 return;
1210
1211         xen_domain_type = XEN_PV_DOMAIN;
1212
1213         xen_setup_machphys_mapping();
1214
1215         /* Install Xen paravirt ops */
1216         pv_info = xen_info;
1217         pv_init_ops = xen_init_ops;
1218         pv_cpu_ops = xen_cpu_ops;
1219         pv_apic_ops = xen_apic_ops;
1220
1221         x86_init.resources.memory_setup = xen_memory_setup;
1222         x86_init.oem.arch_setup = xen_arch_setup;
1223         x86_init.oem.banner = xen_banner;
1224
1225         xen_init_time_ops();
1226
1227         /*
1228          * Set up some pagetable state before starting to set any ptes.
1229          */
1230
1231         xen_init_mmu_ops();
1232
1233         /* Prevent unwanted bits from being set in PTEs. */
1234         __supported_pte_mask &= ~_PAGE_GLOBAL;
1235 #if 0
1236         if (!xen_initial_domain())
1237 #endif
1238                 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1239
1240         __supported_pte_mask |= _PAGE_IOMAP;
1241
1242         /*
1243          * Prevent page tables from being allocated in highmem, even
1244          * if CONFIG_HIGHPTE is enabled.
1245          */
1246         __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
1247
1248         /* Work out if we support NX */
1249         x86_configure_nx();
1250
1251         xen_setup_features();
1252
1253         /* Get mfn list */
1254         if (!xen_feature(XENFEAT_auto_translated_physmap))
1255                 xen_build_dynamic_phys_to_machine();
1256
1257         /*
1258          * Set up kernel GDT and segment registers, mainly so that
1259          * -fstack-protector code can be executed.
1260          */
1261         xen_setup_stackprotector();
1262
1263         xen_init_irq_ops();
1264         xen_init_cpuid_mask();
1265
1266 #ifdef CONFIG_X86_LOCAL_APIC
1267         /*
1268          * set up the basic apic ops.
1269          */
1270         set_xen_basic_apic_ops();
1271 #endif
1272
1273         if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
1274                 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
1275                 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
1276         }
1277
1278         machine_ops = xen_machine_ops;
1279
1280         /*
1281          * The only reliable way to retain the initial address of the
1282          * percpu gdt_page is to remember it here, so we can go and
1283          * mark it RW later, when the initial percpu area is freed.
1284          */
1285         xen_initial_gdt = &per_cpu(gdt_page, 0);
1286
1287         xen_smp_init();
1288
1289 #ifdef CONFIG_ACPI_NUMA
1290         /*
1291          * The pages we from Xen are not related to machine pages, so
1292          * any NUMA information the kernel tries to get from ACPI will
1293          * be meaningless.  Prevent it from trying.
1294          */
1295         acpi_numa = -1;
1296 #endif
1297
1298         pgd = (pgd_t *)xen_start_info->pt_base;
1299
1300         /* Don't do the full vcpu_info placement stuff until we have a
1301            possible map and a non-dummy shared_info. */
1302         per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
1303
1304         local_irq_disable();
1305         early_boot_irqs_disabled = true;
1306
1307         xen_raw_console_write("mapping kernel into physical memory\n");
1308         pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
1309         xen_ident_map_ISA();
1310
1311         /* Allocate and initialize top and mid mfn levels for p2m structure */
1312         xen_build_mfn_list_list();
1313
1314         /* keep using Xen gdt for now; no urgent need to change it */
1315
1316 #ifdef CONFIG_X86_32
1317         pv_info.kernel_rpl = 1;
1318         if (xen_feature(XENFEAT_supervisor_mode_kernel))
1319                 pv_info.kernel_rpl = 0;
1320 #else
1321         pv_info.kernel_rpl = 0;
1322 #endif
1323         /* set the limit of our address space */
1324         xen_reserve_top();
1325
1326         /* We used to do this in xen_arch_setup, but that is too late on AMD
1327          * were early_cpu_init (run before ->arch_setup()) calls early_amd_init
1328          * which pokes 0xcf8 port.
1329          */
1330         set_iopl.iopl = 1;
1331         rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
1332         if (rc != 0)
1333                 xen_raw_printk("physdev_op failed %d\n", rc);
1334
1335 #ifdef CONFIG_X86_32
1336         /* set up basic CPUID stuff */
1337         cpu_detect(&new_cpu_data);
1338         new_cpu_data.hard_math = 1;
1339         new_cpu_data.wp_works_ok = 1;
1340         new_cpu_data.x86_capability[0] = cpuid_edx(1);
1341 #endif
1342
1343         /* Poke various useful things into boot_params */
1344         boot_params.hdr.type_of_loader = (9 << 4) | 0;
1345         boot_params.hdr.ramdisk_image = xen_start_info->mod_start
1346                 ? __pa(xen_start_info->mod_start) : 0;
1347         boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
1348         boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
1349
1350         if (!xen_initial_domain()) {
1351                 add_preferred_console("xenboot", 0, NULL);
1352                 add_preferred_console("tty", 0, NULL);
1353                 add_preferred_console("hvc", 0, NULL);
1354                 if (pci_xen)
1355                         x86_init.pci.arch_init = pci_xen_init;
1356         } else {
1357                 const struct dom0_vga_console_info *info =
1358                         (void *)((char *)xen_start_info +
1359                                  xen_start_info->console.dom0.info_off);
1360
1361                 xen_init_vga(info, xen_start_info->console.dom0.info_size);
1362                 xen_start_info->console.domU.mfn = 0;
1363                 xen_start_info->console.domU.evtchn = 0;
1364
1365                 /* Make sure ACS will be enabled */
1366                 pci_request_acs();
1367         }
1368                 
1369
1370         xen_raw_console_write("about to get started...\n");
1371
1372         xen_setup_runstate_info(0);
1373
1374         /* Start the world */
1375 #ifdef CONFIG_X86_32
1376         i386_start_kernel();
1377 #else
1378         x86_64_start_reservations((char *)__pa_symbol(&boot_params));
1379 #endif
1380 }
1381
1382 static int init_hvm_pv_info(int *major, int *minor)
1383 {
1384         uint32_t eax, ebx, ecx, edx, pages, msr, base;
1385         u64 pfn;
1386
1387         base = xen_cpuid_base();
1388         cpuid(base + 1, &eax, &ebx, &ecx, &edx);
1389
1390         *major = eax >> 16;
1391         *minor = eax & 0xffff;
1392         printk(KERN_INFO "Xen version %d.%d.\n", *major, *minor);
1393
1394         cpuid(base + 2, &pages, &msr, &ecx, &edx);
1395
1396         pfn = __pa(hypercall_page);
1397         wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
1398
1399         xen_setup_features();
1400
1401         pv_info.name = "Xen HVM";
1402
1403         xen_domain_type = XEN_HVM_DOMAIN;
1404
1405         return 0;
1406 }
1407
1408 void __ref xen_hvm_init_shared_info(void)
1409 {
1410         int cpu;
1411         struct xen_add_to_physmap xatp;
1412         static struct shared_info *shared_info_page = 0;
1413
1414         if (!shared_info_page)
1415                 shared_info_page = (struct shared_info *)
1416                         extend_brk(PAGE_SIZE, PAGE_SIZE);
1417         xatp.domid = DOMID_SELF;
1418         xatp.idx = 0;
1419         xatp.space = XENMAPSPACE_shared_info;
1420         xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
1421         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
1422                 BUG();
1423
1424         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
1425
1426         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1427          * page, we use it in the event channel upcall and in some pvclock
1428          * related functions. We don't need the vcpu_info placement
1429          * optimizations because we don't use any pv_mmu or pv_irq op on
1430          * HVM.
1431          * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1432          * online but xen_hvm_init_shared_info is run at resume time too and
1433          * in that case multiple vcpus might be online. */
1434         for_each_online_cpu(cpu) {
1435                 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1436         }
1437 }
1438
1439 #ifdef CONFIG_XEN_PVHVM
1440 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
1441                                     unsigned long action, void *hcpu)
1442 {
1443         int cpu = (long)hcpu;
1444         switch (action) {
1445         case CPU_UP_PREPARE:
1446                 xen_vcpu_setup(cpu);
1447                 if (xen_have_vector_callback)
1448                         xen_init_lock_cpu(cpu);
1449                 break;
1450         default:
1451                 break;
1452         }
1453         return NOTIFY_OK;
1454 }
1455
1456 static struct notifier_block xen_hvm_cpu_notifier __cpuinitdata = {
1457         .notifier_call  = xen_hvm_cpu_notify,
1458 };
1459
1460 static void __init xen_hvm_guest_init(void)
1461 {
1462         int r;
1463         int major, minor;
1464
1465         r = init_hvm_pv_info(&major, &minor);
1466         if (r < 0)
1467                 return;
1468
1469         xen_hvm_init_shared_info();
1470
1471         if (xen_feature(XENFEAT_hvm_callback_vector))
1472                 xen_have_vector_callback = 1;
1473         xen_hvm_smp_init();
1474         register_cpu_notifier(&xen_hvm_cpu_notifier);
1475         xen_unplug_emulated_devices();
1476         x86_init.irqs.intr_init = xen_init_IRQ;
1477         xen_hvm_init_time_ops();
1478         xen_hvm_init_mmu_ops();
1479 }
1480
1481 static bool __init xen_hvm_platform(void)
1482 {
1483         if (xen_pv_domain())
1484                 return false;
1485
1486         if (!xen_cpuid_base())
1487                 return false;
1488
1489         return true;
1490 }
1491
1492 bool xen_hvm_need_lapic(void)
1493 {
1494         if (xen_pv_domain())
1495                 return false;
1496         if (!xen_hvm_domain())
1497                 return false;
1498         if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
1499                 return false;
1500         return true;
1501 }
1502 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
1503
1504 const struct hypervisor_x86 x86_hyper_xen_hvm __refconst = {
1505         .name                   = "Xen HVM",
1506         .detect                 = xen_hvm_platform,
1507         .init_platform          = xen_hvm_guest_init,
1508 };
1509 EXPORT_SYMBOL(x86_hyper_xen_hvm);
1510 #endif