2 * Core of Xen paravirt_ops implementation.
4 * This file contains the xen_paravirt_ops structure itself, and the
6 * - privileged instructions
11 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
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>
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>
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>
44 #include <xen/hvc-console.h>
47 #include <asm/paravirt.h>
50 #include <asm/xen/pci.h>
51 #include <asm/xen/hypercall.h>
52 #include <asm/xen/hypervisor.h>
53 #include <asm/fixmap.h>
54 #include <asm/processor.h>
55 #include <asm/proto.h>
56 #include <asm/msr-index.h>
57 #include <asm/traps.h>
58 #include <asm/setup.h>
60 #include <asm/pgalloc.h>
61 #include <asm/pgtable.h>
62 #include <asm/tlbflush.h>
63 #include <asm/reboot.h>
64 #include <asm/stackprotector.h>
65 #include <asm/hypervisor.h>
66 #include <asm/mwait.h>
67 #include <asm/pci_x86.h>
70 #include <linux/acpi.h>
72 #include <acpi/pdc_intel.h>
73 #include <acpi/processor.h>
74 #include <xen/interface/platform.h>
80 #include "multicalls.h"
82 EXPORT_SYMBOL_GPL(hypercall_page);
84 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
85 DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
87 enum xen_domain_type xen_domain_type = XEN_NATIVE;
88 EXPORT_SYMBOL_GPL(xen_domain_type);
90 unsigned long *machine_to_phys_mapping = (void *)MACH2PHYS_VIRT_START;
91 EXPORT_SYMBOL(machine_to_phys_mapping);
92 unsigned long machine_to_phys_nr;
93 EXPORT_SYMBOL(machine_to_phys_nr);
95 struct start_info *xen_start_info;
96 EXPORT_SYMBOL_GPL(xen_start_info);
98 struct shared_info xen_dummy_shared_info;
100 void *xen_initial_gdt;
102 RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
103 __read_mostly int xen_have_vector_callback;
104 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
107 * Point at some empty memory to start with. We map the real shared_info
108 * page as soon as fixmap is up and running.
110 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
113 * Flag to determine whether vcpu info placement is available on all
114 * VCPUs. We assume it is to start with, and then set it to zero on
115 * the first failure. This is because it can succeed on some VCPUs
116 * and not others, since it can involve hypervisor memory allocation,
117 * or because the guest failed to guarantee all the appropriate
118 * constraints on all VCPUs (ie buffer can't cross a page boundary).
120 * Note that any particular CPU may be using a placed vcpu structure,
121 * but we can only optimise if the all are.
123 * 0: not available, 1: available
125 static int have_vcpu_info_placement = 1;
127 static void clamp_max_cpus(void)
130 if (setup_max_cpus > MAX_VIRT_CPUS)
131 setup_max_cpus = MAX_VIRT_CPUS;
135 static void xen_vcpu_setup(int cpu)
137 struct vcpu_register_vcpu_info info;
139 struct vcpu_info *vcpup;
141 BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
143 if (cpu < MAX_VIRT_CPUS)
144 per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
146 if (!have_vcpu_info_placement) {
147 if (cpu >= MAX_VIRT_CPUS)
152 vcpup = &per_cpu(xen_vcpu_info, cpu);
153 info.mfn = arbitrary_virt_to_mfn(vcpup);
154 info.offset = offset_in_page(vcpup);
156 /* Check to see if the hypervisor will put the vcpu_info
157 structure where we want it, which allows direct access via
158 a percpu-variable. */
159 err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
162 printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
163 have_vcpu_info_placement = 0;
166 /* This cpu is using the registered vcpu info, even if
167 later ones fail to. */
168 per_cpu(xen_vcpu, cpu) = vcpup;
173 * On restore, set the vcpu placement up again.
174 * If it fails, then we're in a bad state, since
175 * we can't back out from using it...
177 void xen_vcpu_restore(void)
181 for_each_online_cpu(cpu) {
182 bool other_cpu = (cpu != smp_processor_id());
185 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL))
188 xen_setup_runstate_info(cpu);
190 if (have_vcpu_info_placement)
194 HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL))
199 static void __init xen_banner(void)
201 unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
202 struct xen_extraversion extra;
203 HYPERVISOR_xen_version(XENVER_extraversion, &extra);
205 printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
207 printk(KERN_INFO "Xen version: %d.%d%s%s\n",
208 version >> 16, version & 0xffff, extra.extraversion,
209 xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
212 static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
213 static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
215 static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask;
216 static __read_mostly unsigned int cpuid_leaf5_ecx_val;
217 static __read_mostly unsigned int cpuid_leaf5_edx_val;
219 static void xen_cpuid(unsigned int *ax, unsigned int *bx,
220 unsigned int *cx, unsigned int *dx)
222 unsigned maskebx = ~0;
223 unsigned maskecx = ~0;
224 unsigned maskedx = ~0;
227 * Mask out inconvenient features, to try and disable as many
228 * unsupported kernel subsystems as possible.
232 maskecx = cpuid_leaf1_ecx_mask;
233 setecx = cpuid_leaf1_ecx_set_mask;
234 maskedx = cpuid_leaf1_edx_mask;
237 case CPUID_MWAIT_LEAF:
238 /* Synthesize the values.. */
241 *cx = cpuid_leaf5_ecx_val;
242 *dx = cpuid_leaf5_edx_val;
246 /* Suppress extended topology stuff */
251 asm(XEN_EMULATE_PREFIX "cpuid"
256 : "0" (*ax), "2" (*cx));
265 static bool __init xen_check_mwait(void)
267 #if defined(CONFIG_ACPI) && !defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) && \
268 !defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
269 struct xen_platform_op op = {
270 .cmd = XENPF_set_processor_pminfo,
271 .u.set_pminfo.id = -1,
272 .u.set_pminfo.type = XEN_PM_PDC,
275 unsigned int ax, bx, cx, dx;
276 unsigned int mwait_mask;
278 /* We need to determine whether it is OK to expose the MWAIT
279 * capability to the kernel to harvest deeper than C3 states from ACPI
280 * _CST using the processor_harvest_xen.c module. For this to work, we
281 * need to gather the MWAIT_LEAF values (which the cstate.c code
282 * checks against). The hypervisor won't expose the MWAIT flag because
283 * it would break backwards compatibility; so we will find out directly
284 * from the hardware and hypercall.
286 if (!xen_initial_domain())
292 native_cpuid(&ax, &bx, &cx, &dx);
294 mwait_mask = (1 << (X86_FEATURE_EST % 32)) |
295 (1 << (X86_FEATURE_MWAIT % 32));
297 if ((cx & mwait_mask) != mwait_mask)
300 /* We need to emulate the MWAIT_LEAF and for that we need both
301 * ecx and edx. The hypercall provides only partial information.
304 ax = CPUID_MWAIT_LEAF;
309 native_cpuid(&ax, &bx, &cx, &dx);
311 /* Ask the Hypervisor whether to clear ACPI_PDC_C_C2C3_FFH. If so,
312 * don't expose MWAIT_LEAF and let ACPI pick the IOPORT version of C3.
314 buf[0] = ACPI_PDC_REVISION_ID;
316 buf[2] = (ACPI_PDC_C_CAPABILITY_SMP | ACPI_PDC_EST_CAPABILITY_SWSMP);
318 set_xen_guest_handle(op.u.set_pminfo.pdc, buf);
320 if ((HYPERVISOR_dom0_op(&op) == 0) &&
321 (buf[2] & (ACPI_PDC_C_C1_FFH | ACPI_PDC_C_C2C3_FFH))) {
322 cpuid_leaf5_ecx_val = cx;
323 cpuid_leaf5_edx_val = dx;
330 static void __init xen_init_cpuid_mask(void)
332 unsigned int ax, bx, cx, dx;
333 unsigned int xsave_mask;
335 cpuid_leaf1_edx_mask =
336 ~((1 << X86_FEATURE_MCE) | /* disable MCE */
337 (1 << X86_FEATURE_MCA) | /* disable MCA */
338 (1 << X86_FEATURE_MTRR) | /* disable MTRR */
339 (1 << X86_FEATURE_ACC)); /* thermal monitoring */
341 if (!xen_initial_domain())
342 cpuid_leaf1_edx_mask &=
343 ~((1 << X86_FEATURE_APIC) | /* disable local APIC */
344 (1 << X86_FEATURE_ACPI)); /* disable ACPI */
347 xen_cpuid(&ax, &bx, &cx, &dx);
350 (1 << (X86_FEATURE_XSAVE % 32)) |
351 (1 << (X86_FEATURE_OSXSAVE % 32));
353 /* Xen will set CR4.OSXSAVE if supported and not disabled by force */
354 if ((cx & xsave_mask) != xsave_mask)
355 cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */
356 if (xen_check_mwait())
357 cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32));
360 static void xen_set_debugreg(int reg, unsigned long val)
362 HYPERVISOR_set_debugreg(reg, val);
365 static unsigned long xen_get_debugreg(int reg)
367 return HYPERVISOR_get_debugreg(reg);
370 static void xen_end_context_switch(struct task_struct *next)
373 paravirt_end_context_switch(next);
376 static unsigned long xen_store_tr(void)
382 * Set the page permissions for a particular virtual address. If the
383 * address is a vmalloc mapping (or other non-linear mapping), then
384 * find the linear mapping of the page and also set its protections to
387 static void set_aliased_prot(void *v, pgprot_t prot)
395 ptep = lookup_address((unsigned long)v, &level);
396 BUG_ON(ptep == NULL);
398 pfn = pte_pfn(*ptep);
399 page = pfn_to_page(pfn);
401 pte = pfn_pte(pfn, prot);
403 if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
406 if (!PageHighMem(page)) {
407 void *av = __va(PFN_PHYS(pfn));
410 if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
416 static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
418 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
421 for(i = 0; i < entries; i += entries_per_page)
422 set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
425 static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
427 const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
430 for(i = 0; i < entries; i += entries_per_page)
431 set_aliased_prot(ldt + i, PAGE_KERNEL);
434 static void xen_set_ldt(const void *addr, unsigned entries)
436 struct mmuext_op *op;
437 struct multicall_space mcs = xen_mc_entry(sizeof(*op));
439 trace_xen_cpu_set_ldt(addr, entries);
442 op->cmd = MMUEXT_SET_LDT;
443 op->arg1.linear_addr = (unsigned long)addr;
444 op->arg2.nr_ents = entries;
446 MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
448 xen_mc_issue(PARAVIRT_LAZY_CPU);
451 static void xen_load_gdt(const struct desc_ptr *dtr)
453 unsigned long va = dtr->address;
454 unsigned int size = dtr->size + 1;
455 unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
456 unsigned long frames[pages];
460 * A GDT can be up to 64k in size, which corresponds to 8192
461 * 8-byte entries, or 16 4k pages..
464 BUG_ON(size > 65536);
465 BUG_ON(va & ~PAGE_MASK);
467 for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
470 unsigned long pfn, mfn;
474 * The GDT is per-cpu and is in the percpu data area.
475 * That can be virtually mapped, so we need to do a
476 * page-walk to get the underlying MFN for the
477 * hypercall. The page can also be in the kernel's
478 * linear range, so we need to RO that mapping too.
480 ptep = lookup_address(va, &level);
481 BUG_ON(ptep == NULL);
483 pfn = pte_pfn(*ptep);
484 mfn = pfn_to_mfn(pfn);
485 virt = __va(PFN_PHYS(pfn));
489 make_lowmem_page_readonly((void *)va);
490 make_lowmem_page_readonly(virt);
493 if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
498 * load_gdt for early boot, when the gdt is only mapped once
500 static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
502 unsigned long va = dtr->address;
503 unsigned int size = dtr->size + 1;
504 unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
505 unsigned long frames[pages];
509 * A GDT can be up to 64k in size, which corresponds to 8192
510 * 8-byte entries, or 16 4k pages..
513 BUG_ON(size > 65536);
514 BUG_ON(va & ~PAGE_MASK);
516 for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
518 unsigned long pfn, mfn;
520 pfn = virt_to_pfn(va);
521 mfn = pfn_to_mfn(pfn);
523 pte = pfn_pte(pfn, PAGE_KERNEL_RO);
525 if (HYPERVISOR_update_va_mapping((unsigned long)va, pte, 0))
531 if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
535 static void load_TLS_descriptor(struct thread_struct *t,
536 unsigned int cpu, unsigned int i)
538 struct desc_struct *gdt = get_cpu_gdt_table(cpu);
539 xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
540 struct multicall_space mc = __xen_mc_entry(0);
542 MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
545 static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
548 * XXX sleazy hack: If we're being called in a lazy-cpu zone
549 * and lazy gs handling is enabled, it means we're in a
550 * context switch, and %gs has just been saved. This means we
551 * can zero it out to prevent faults on exit from the
552 * hypervisor if the next process has no %gs. Either way, it
553 * has been saved, and the new value will get loaded properly.
554 * This will go away as soon as Xen has been modified to not
555 * save/restore %gs for normal hypercalls.
557 * On x86_64, this hack is not used for %gs, because gs points
558 * to KERNEL_GS_BASE (and uses it for PDA references), so we
559 * must not zero %gs on x86_64
561 * For x86_64, we need to zero %fs, otherwise we may get an
562 * exception between the new %fs descriptor being loaded and
563 * %fs being effectively cleared at __switch_to().
565 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
575 load_TLS_descriptor(t, cpu, 0);
576 load_TLS_descriptor(t, cpu, 1);
577 load_TLS_descriptor(t, cpu, 2);
579 xen_mc_issue(PARAVIRT_LAZY_CPU);
583 static void xen_load_gs_index(unsigned int idx)
585 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
590 static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
593 xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
594 u64 entry = *(u64 *)ptr;
596 trace_xen_cpu_write_ldt_entry(dt, entrynum, entry);
601 if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
607 static int cvt_gate_to_trap(int vector, const gate_desc *val,
608 struct trap_info *info)
612 if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
615 info->vector = vector;
617 addr = gate_offset(*val);
620 * Look for known traps using IST, and substitute them
621 * appropriately. The debugger ones are the only ones we care
622 * about. Xen will handle faults like double_fault and
623 * machine_check, so we should never see them. Warn if
624 * there's an unexpected IST-using fault handler.
626 if (addr == (unsigned long)debug)
627 addr = (unsigned long)xen_debug;
628 else if (addr == (unsigned long)int3)
629 addr = (unsigned long)xen_int3;
630 else if (addr == (unsigned long)stack_segment)
631 addr = (unsigned long)xen_stack_segment;
632 else if (addr == (unsigned long)double_fault ||
633 addr == (unsigned long)nmi) {
634 /* Don't need to handle these */
636 #ifdef CONFIG_X86_MCE
637 } else if (addr == (unsigned long)machine_check) {
641 /* Some other trap using IST? */
642 if (WARN_ON(val->ist != 0))
645 #endif /* CONFIG_X86_64 */
646 info->address = addr;
648 info->cs = gate_segment(*val);
649 info->flags = val->dpl;
650 /* interrupt gates clear IF */
651 if (val->type == GATE_INTERRUPT)
652 info->flags |= 1 << 2;
657 /* Locations of each CPU's IDT */
658 static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
660 /* Set an IDT entry. If the entry is part of the current IDT, then
662 static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
664 unsigned long p = (unsigned long)&dt[entrynum];
665 unsigned long start, end;
667 trace_xen_cpu_write_idt_entry(dt, entrynum, g);
671 start = __this_cpu_read(idt_desc.address);
672 end = start + __this_cpu_read(idt_desc.size) + 1;
676 native_write_idt_entry(dt, entrynum, g);
678 if (p >= start && (p + 8) <= end) {
679 struct trap_info info[2];
683 if (cvt_gate_to_trap(entrynum, g, &info[0]))
684 if (HYPERVISOR_set_trap_table(info))
691 static void xen_convert_trap_info(const struct desc_ptr *desc,
692 struct trap_info *traps)
694 unsigned in, out, count;
696 count = (desc->size+1) / sizeof(gate_desc);
699 for (in = out = 0; in < count; in++) {
700 gate_desc *entry = (gate_desc*)(desc->address) + in;
702 if (cvt_gate_to_trap(in, entry, &traps[out]))
705 traps[out].address = 0;
708 void xen_copy_trap_info(struct trap_info *traps)
710 const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
712 xen_convert_trap_info(desc, traps);
715 /* Load a new IDT into Xen. In principle this can be per-CPU, so we
716 hold a spinlock to protect the static traps[] array (static because
717 it avoids allocation, and saves stack space). */
718 static void xen_load_idt(const struct desc_ptr *desc)
720 static DEFINE_SPINLOCK(lock);
721 static struct trap_info traps[257];
723 trace_xen_cpu_load_idt(desc);
727 __get_cpu_var(idt_desc) = *desc;
729 xen_convert_trap_info(desc, traps);
732 if (HYPERVISOR_set_trap_table(traps))
738 /* Write a GDT descriptor entry. Ignore LDT descriptors, since
739 they're handled differently. */
740 static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
741 const void *desc, int type)
743 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
754 xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
757 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
767 * Version of write_gdt_entry for use at early boot-time needed to
768 * update an entry as simply as possible.
770 static void __init xen_write_gdt_entry_boot(struct desc_struct *dt, int entry,
771 const void *desc, int type)
773 trace_xen_cpu_write_gdt_entry(dt, entry, desc, type);
782 xmaddr_t maddr = virt_to_machine(&dt[entry]);
784 if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
785 dt[entry] = *(struct desc_struct *)desc;
791 static void xen_load_sp0(struct tss_struct *tss,
792 struct thread_struct *thread)
794 struct multicall_space mcs;
796 mcs = xen_mc_entry(0);
797 MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
798 xen_mc_issue(PARAVIRT_LAZY_CPU);
801 static void xen_set_iopl_mask(unsigned mask)
803 struct physdev_set_iopl set_iopl;
805 /* Force the change at ring 0. */
806 set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
807 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
810 static void xen_io_delay(void)
814 #ifdef CONFIG_X86_LOCAL_APIC
815 static unsigned long xen_set_apic_id(unsigned int x)
820 static unsigned int xen_get_apic_id(unsigned long x)
822 return ((x)>>24) & 0xFFu;
824 static u32 xen_apic_read(u32 reg)
826 struct xen_platform_op op = {
827 .cmd = XENPF_get_cpuinfo,
828 .interface_version = XENPF_INTERFACE_VERSION,
829 .u.pcpu_info.xen_cpuid = 0,
833 /* Shouldn't need this as APIC is turned off for PV, and we only
834 * get called on the bootup processor. But just in case. */
835 if (!xen_initial_domain() || smp_processor_id())
844 ret = HYPERVISOR_dom0_op(&op);
848 return op.u.pcpu_info.apic_id << 24;
851 static void xen_apic_write(u32 reg, u32 val)
853 /* Warn to see if there's any stray references */
857 static u64 xen_apic_icr_read(void)
862 static void xen_apic_icr_write(u32 low, u32 id)
864 /* Warn to see if there's any stray references */
868 static void xen_apic_wait_icr_idle(void)
873 static u32 xen_safe_apic_wait_icr_idle(void)
878 static void set_xen_basic_apic_ops(void)
880 apic->read = xen_apic_read;
881 apic->write = xen_apic_write;
882 apic->icr_read = xen_apic_icr_read;
883 apic->icr_write = xen_apic_icr_write;
884 apic->wait_icr_idle = xen_apic_wait_icr_idle;
885 apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
886 apic->set_apic_id = xen_set_apic_id;
887 apic->get_apic_id = xen_get_apic_id;
890 apic->send_IPI_allbutself = xen_send_IPI_allbutself;
891 apic->send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself;
892 apic->send_IPI_mask = xen_send_IPI_mask;
893 apic->send_IPI_all = xen_send_IPI_all;
894 apic->send_IPI_self = xen_send_IPI_self;
900 static void xen_clts(void)
902 struct multicall_space mcs;
904 mcs = xen_mc_entry(0);
906 MULTI_fpu_taskswitch(mcs.mc, 0);
908 xen_mc_issue(PARAVIRT_LAZY_CPU);
911 static DEFINE_PER_CPU(unsigned long, xen_cr0_value);
913 static unsigned long xen_read_cr0(void)
915 unsigned long cr0 = this_cpu_read(xen_cr0_value);
917 if (unlikely(cr0 == 0)) {
918 cr0 = native_read_cr0();
919 this_cpu_write(xen_cr0_value, cr0);
925 static void xen_write_cr0(unsigned long cr0)
927 struct multicall_space mcs;
929 this_cpu_write(xen_cr0_value, cr0);
931 /* Only pay attention to cr0.TS; everything else is
933 mcs = xen_mc_entry(0);
935 MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
937 xen_mc_issue(PARAVIRT_LAZY_CPU);
940 static void xen_write_cr4(unsigned long cr4)
945 native_write_cr4(cr4);
948 static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
959 case MSR_FS_BASE: which = SEGBASE_FS; goto set;
960 case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set;
961 case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set;
964 base = ((u64)high << 32) | low;
965 if (HYPERVISOR_set_segment_base(which, base) != 0)
973 case MSR_SYSCALL_MASK:
974 case MSR_IA32_SYSENTER_CS:
975 case MSR_IA32_SYSENTER_ESP:
976 case MSR_IA32_SYSENTER_EIP:
977 /* Fast syscall setup is all done in hypercalls, so
978 these are all ignored. Stub them out here to stop
979 Xen console noise. */
982 case MSR_IA32_CR_PAT:
983 if (smp_processor_id() == 0)
984 xen_set_pat(((u64)high << 32) | low);
988 ret = native_write_msr_safe(msr, low, high);
994 void xen_setup_shared_info(void)
996 if (!xen_feature(XENFEAT_auto_translated_physmap)) {
997 set_fixmap(FIX_PARAVIRT_BOOTMAP,
998 xen_start_info->shared_info);
1000 HYPERVISOR_shared_info =
1001 (struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
1003 HYPERVISOR_shared_info =
1004 (struct shared_info *)__va(xen_start_info->shared_info);
1007 /* In UP this is as good a place as any to set up shared info */
1008 xen_setup_vcpu_info_placement();
1011 xen_setup_mfn_list_list();
1014 /* This is called once we have the cpu_possible_mask */
1015 void xen_setup_vcpu_info_placement(void)
1019 for_each_possible_cpu(cpu)
1020 xen_vcpu_setup(cpu);
1022 /* xen_vcpu_setup managed to place the vcpu_info within the
1023 percpu area for all cpus, so make use of it */
1024 if (have_vcpu_info_placement) {
1025 pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
1026 pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
1027 pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
1028 pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
1029 pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
1033 static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
1034 unsigned long addr, unsigned len)
1036 char *start, *end, *reloc;
1039 start = end = reloc = NULL;
1041 #define SITE(op, x) \
1042 case PARAVIRT_PATCH(op.x): \
1043 if (have_vcpu_info_placement) { \
1044 start = (char *)xen_##x##_direct; \
1045 end = xen_##x##_direct_end; \
1046 reloc = xen_##x##_direct_reloc; \
1051 SITE(pv_irq_ops, irq_enable);
1052 SITE(pv_irq_ops, irq_disable);
1053 SITE(pv_irq_ops, save_fl);
1054 SITE(pv_irq_ops, restore_fl);
1058 if (start == NULL || (end-start) > len)
1061 ret = paravirt_patch_insns(insnbuf, len, start, end);
1063 /* Note: because reloc is assigned from something that
1064 appears to be an array, gcc assumes it's non-null,
1065 but doesn't know its relationship with start and
1067 if (reloc > start && reloc < end) {
1068 int reloc_off = reloc - start;
1069 long *relocp = (long *)(insnbuf + reloc_off);
1070 long delta = start - (char *)addr;
1078 ret = paravirt_patch_default(type, clobbers, insnbuf,
1086 static const struct pv_info xen_info __initconst = {
1087 .paravirt_enabled = 1,
1088 .shared_kernel_pmd = 0,
1090 #ifdef CONFIG_X86_64
1091 .extra_user_64bit_cs = FLAT_USER_CS64,
1097 static const struct pv_init_ops xen_init_ops __initconst = {
1101 static const struct pv_cpu_ops xen_cpu_ops __initconst = {
1104 .set_debugreg = xen_set_debugreg,
1105 .get_debugreg = xen_get_debugreg,
1109 .read_cr0 = xen_read_cr0,
1110 .write_cr0 = xen_write_cr0,
1112 .read_cr4 = native_read_cr4,
1113 .read_cr4_safe = native_read_cr4_safe,
1114 .write_cr4 = xen_write_cr4,
1116 .wbinvd = native_wbinvd,
1118 .read_msr = native_read_msr_safe,
1119 .write_msr = xen_write_msr_safe,
1120 .read_tsc = native_read_tsc,
1121 .read_pmc = native_read_pmc,
1124 .irq_enable_sysexit = xen_sysexit,
1125 #ifdef CONFIG_X86_64
1126 .usergs_sysret32 = xen_sysret32,
1127 .usergs_sysret64 = xen_sysret64,
1130 .load_tr_desc = paravirt_nop,
1131 .set_ldt = xen_set_ldt,
1132 .load_gdt = xen_load_gdt,
1133 .load_idt = xen_load_idt,
1134 .load_tls = xen_load_tls,
1135 #ifdef CONFIG_X86_64
1136 .load_gs_index = xen_load_gs_index,
1139 .alloc_ldt = xen_alloc_ldt,
1140 .free_ldt = xen_free_ldt,
1142 .store_gdt = native_store_gdt,
1143 .store_idt = native_store_idt,
1144 .store_tr = xen_store_tr,
1146 .write_ldt_entry = xen_write_ldt_entry,
1147 .write_gdt_entry = xen_write_gdt_entry,
1148 .write_idt_entry = xen_write_idt_entry,
1149 .load_sp0 = xen_load_sp0,
1151 .set_iopl_mask = xen_set_iopl_mask,
1152 .io_delay = xen_io_delay,
1154 /* Xen takes care of %gs when switching to usermode for us */
1155 .swapgs = paravirt_nop,
1157 .start_context_switch = paravirt_start_context_switch,
1158 .end_context_switch = xen_end_context_switch,
1161 static const struct pv_apic_ops xen_apic_ops __initconst = {
1162 #ifdef CONFIG_X86_LOCAL_APIC
1163 .startup_ipi_hook = paravirt_nop,
1167 static void xen_reboot(int reason)
1169 struct sched_shutdown r = { .reason = reason };
1171 if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
1175 static void xen_restart(char *msg)
1177 xen_reboot(SHUTDOWN_reboot);
1180 static void xen_emergency_restart(void)
1182 xen_reboot(SHUTDOWN_reboot);
1185 static void xen_machine_halt(void)
1187 xen_reboot(SHUTDOWN_poweroff);
1190 static void xen_machine_power_off(void)
1194 xen_reboot(SHUTDOWN_poweroff);
1197 static void xen_crash_shutdown(struct pt_regs *regs)
1199 xen_reboot(SHUTDOWN_crash);
1203 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
1205 xen_reboot(SHUTDOWN_crash);
1209 static struct notifier_block xen_panic_block = {
1210 .notifier_call= xen_panic_event,
1213 int xen_panic_handler_init(void)
1215 atomic_notifier_chain_register(&panic_notifier_list, &xen_panic_block);
1219 static const struct machine_ops xen_machine_ops __initconst = {
1220 .restart = xen_restart,
1221 .halt = xen_machine_halt,
1222 .power_off = xen_machine_power_off,
1223 .shutdown = xen_machine_halt,
1224 .crash_shutdown = xen_crash_shutdown,
1225 .emergency_restart = xen_emergency_restart,
1229 * Set up the GDT and segment registers for -fstack-protector. Until
1230 * we do this, we have to be careful not to call any stack-protected
1231 * function, which is most of the kernel.
1233 static void __init xen_setup_stackprotector(void)
1235 pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry_boot;
1236 pv_cpu_ops.load_gdt = xen_load_gdt_boot;
1238 setup_stack_canary_segment(0);
1239 switch_to_new_gdt(0);
1241 pv_cpu_ops.write_gdt_entry = xen_write_gdt_entry;
1242 pv_cpu_ops.load_gdt = xen_load_gdt;
1245 /* First C function to be called on Xen boot */
1246 asmlinkage void __init xen_start_kernel(void)
1248 struct physdev_set_iopl set_iopl;
1252 if (!xen_start_info)
1255 xen_domain_type = XEN_PV_DOMAIN;
1257 xen_setup_machphys_mapping();
1259 /* Install Xen paravirt ops */
1261 pv_init_ops = xen_init_ops;
1262 pv_cpu_ops = xen_cpu_ops;
1263 pv_apic_ops = xen_apic_ops;
1265 x86_init.resources.memory_setup = xen_memory_setup;
1266 x86_init.oem.arch_setup = xen_arch_setup;
1267 x86_init.oem.banner = xen_banner;
1269 xen_init_time_ops();
1272 * Set up some pagetable state before starting to set any ptes.
1277 /* Prevent unwanted bits from being set in PTEs. */
1278 __supported_pte_mask &= ~_PAGE_GLOBAL;
1280 if (!xen_initial_domain())
1282 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1284 __supported_pte_mask |= _PAGE_IOMAP;
1287 * Prevent page tables from being allocated in highmem, even
1288 * if CONFIG_HIGHPTE is enabled.
1290 __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
1292 /* Work out if we support NX */
1295 xen_setup_features();
1298 if (!xen_feature(XENFEAT_auto_translated_physmap))
1299 xen_build_dynamic_phys_to_machine();
1302 * Set up kernel GDT and segment registers, mainly so that
1303 * -fstack-protector code can be executed.
1305 xen_setup_stackprotector();
1308 xen_init_cpuid_mask();
1310 #ifdef CONFIG_X86_LOCAL_APIC
1312 * set up the basic apic ops.
1314 set_xen_basic_apic_ops();
1317 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
1318 pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
1319 pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
1322 machine_ops = xen_machine_ops;
1325 * The only reliable way to retain the initial address of the
1326 * percpu gdt_page is to remember it here, so we can go and
1327 * mark it RW later, when the initial percpu area is freed.
1329 xen_initial_gdt = &per_cpu(gdt_page, 0);
1333 #ifdef CONFIG_ACPI_NUMA
1335 * The pages we from Xen are not related to machine pages, so
1336 * any NUMA information the kernel tries to get from ACPI will
1337 * be meaningless. Prevent it from trying.
1342 pgd = (pgd_t *)xen_start_info->pt_base;
1344 /* Don't do the full vcpu_info placement stuff until we have a
1345 possible map and a non-dummy shared_info. */
1346 per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
1348 local_irq_disable();
1349 early_boot_irqs_disabled = true;
1351 xen_raw_console_write("mapping kernel into physical memory\n");
1352 pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
1354 /* Allocate and initialize top and mid mfn levels for p2m structure */
1355 xen_build_mfn_list_list();
1357 /* keep using Xen gdt for now; no urgent need to change it */
1359 #ifdef CONFIG_X86_32
1360 pv_info.kernel_rpl = 1;
1361 if (xen_feature(XENFEAT_supervisor_mode_kernel))
1362 pv_info.kernel_rpl = 0;
1364 pv_info.kernel_rpl = 0;
1366 /* set the limit of our address space */
1369 /* We used to do this in xen_arch_setup, but that is too late on AMD
1370 * were early_cpu_init (run before ->arch_setup()) calls early_amd_init
1371 * which pokes 0xcf8 port.
1374 rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
1376 xen_raw_printk("physdev_op failed %d\n", rc);
1378 #ifdef CONFIG_X86_32
1379 /* set up basic CPUID stuff */
1380 cpu_detect(&new_cpu_data);
1381 new_cpu_data.hard_math = 1;
1382 new_cpu_data.wp_works_ok = 1;
1383 new_cpu_data.x86_capability[0] = cpuid_edx(1);
1386 /* Poke various useful things into boot_params */
1387 boot_params.hdr.type_of_loader = (9 << 4) | 0;
1388 boot_params.hdr.ramdisk_image = xen_start_info->mod_start
1389 ? __pa(xen_start_info->mod_start) : 0;
1390 boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
1391 boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
1393 if (!xen_initial_domain()) {
1394 add_preferred_console("xenboot", 0, NULL);
1395 add_preferred_console("tty", 0, NULL);
1396 add_preferred_console("hvc", 0, NULL);
1398 x86_init.pci.arch_init = pci_xen_init;
1400 const struct dom0_vga_console_info *info =
1401 (void *)((char *)xen_start_info +
1402 xen_start_info->console.dom0.info_off);
1404 xen_init_vga(info, xen_start_info->console.dom0.info_size);
1405 xen_start_info->console.domU.mfn = 0;
1406 xen_start_info->console.domU.evtchn = 0;
1410 /* Make sure ACS will be enabled */
1413 xen_acpi_sleep_register();
1416 /* PCI BIOS service won't work from a PV guest. */
1417 pci_probe &= ~PCI_PROBE_BIOS;
1419 xen_raw_console_write("about to get started...\n");
1421 xen_setup_runstate_info(0);
1423 /* Start the world */
1424 #ifdef CONFIG_X86_32
1425 i386_start_kernel();
1427 x86_64_start_reservations((char *)__pa_symbol(&boot_params));
1431 static int init_hvm_pv_info(int *major, int *minor)
1433 uint32_t eax, ebx, ecx, edx, pages, msr, base;
1436 base = xen_cpuid_base();
1437 cpuid(base + 1, &eax, &ebx, &ecx, &edx);
1440 *minor = eax & 0xffff;
1441 printk(KERN_INFO "Xen version %d.%d.\n", *major, *minor);
1443 cpuid(base + 2, &pages, &msr, &ecx, &edx);
1445 pfn = __pa(hypercall_page);
1446 wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
1448 xen_setup_features();
1450 pv_info.name = "Xen HVM";
1452 xen_domain_type = XEN_HVM_DOMAIN;
1457 void __ref xen_hvm_init_shared_info(void)
1460 struct xen_add_to_physmap xatp;
1461 static struct shared_info *shared_info_page = 0;
1463 if (!shared_info_page)
1464 shared_info_page = (struct shared_info *)
1465 extend_brk(PAGE_SIZE, PAGE_SIZE);
1466 xatp.domid = DOMID_SELF;
1468 xatp.space = XENMAPSPACE_shared_info;
1469 xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
1470 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
1473 HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
1475 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1476 * page, we use it in the event channel upcall and in some pvclock
1477 * related functions. We don't need the vcpu_info placement
1478 * optimizations because we don't use any pv_mmu or pv_irq op on
1480 * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1481 * online but xen_hvm_init_shared_info is run at resume time too and
1482 * in that case multiple vcpus might be online. */
1483 for_each_online_cpu(cpu) {
1484 per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
1488 #ifdef CONFIG_XEN_PVHVM
1489 static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
1490 unsigned long action, void *hcpu)
1492 int cpu = (long)hcpu;
1494 case CPU_UP_PREPARE:
1495 xen_vcpu_setup(cpu);
1496 if (xen_have_vector_callback)
1497 xen_init_lock_cpu(cpu);
1505 static struct notifier_block xen_hvm_cpu_notifier __cpuinitdata = {
1506 .notifier_call = xen_hvm_cpu_notify,
1509 static void __init xen_hvm_guest_init(void)
1514 r = init_hvm_pv_info(&major, &minor);
1518 xen_hvm_init_shared_info();
1520 if (xen_feature(XENFEAT_hvm_callback_vector))
1521 xen_have_vector_callback = 1;
1523 register_cpu_notifier(&xen_hvm_cpu_notifier);
1524 xen_unplug_emulated_devices();
1525 x86_init.irqs.intr_init = xen_init_IRQ;
1526 xen_hvm_init_time_ops();
1527 xen_hvm_init_mmu_ops();
1530 static bool __init xen_hvm_platform(void)
1532 if (xen_pv_domain())
1535 if (!xen_cpuid_base())
1541 bool xen_hvm_need_lapic(void)
1543 if (xen_pv_domain())
1545 if (!xen_hvm_domain())
1547 if (xen_feature(XENFEAT_hvm_pirqs) && xen_have_vector_callback)
1551 EXPORT_SYMBOL_GPL(xen_hvm_need_lapic);
1553 const struct hypervisor_x86 x86_hyper_xen_hvm __refconst = {
1555 .detect = xen_hvm_platform,
1556 .init_platform = xen_hvm_guest_init,
1558 EXPORT_SYMBOL(x86_hyper_xen_hvm);