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/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/bootmem.h>
24 #include <linux/module.h>
26 #include <linux/page-flags.h>
27 #include <linux/highmem.h>
28 #include <linux/console.h>
30 #include <xen/interface/xen.h>
31 #include <xen/interface/version.h>
32 #include <xen/interface/physdev.h>
33 #include <xen/interface/vcpu.h>
34 #include <xen/features.h>
36 #include <xen/hvc-console.h>
38 #include <asm/paravirt.h>
41 #include <asm/xen/hypercall.h>
42 #include <asm/xen/hypervisor.h>
43 #include <asm/fixmap.h>
44 #include <asm/processor.h>
45 #include <asm/proto.h>
46 #include <asm/msr-index.h>
47 #include <asm/setup.h>
49 #include <asm/pgtable.h>
50 #include <asm/tlbflush.h>
51 #include <asm/reboot.h>
55 #include "multicalls.h"
57 EXPORT_SYMBOL_GPL(hypercall_page
);
59 DEFINE_PER_CPU(struct vcpu_info
*, xen_vcpu
);
60 DEFINE_PER_CPU(struct vcpu_info
, xen_vcpu_info
);
62 enum xen_domain_type xen_domain_type
= XEN_NATIVE
;
63 EXPORT_SYMBOL_GPL(xen_domain_type
);
65 struct start_info
*xen_start_info
;
66 EXPORT_SYMBOL_GPL(xen_start_info
);
68 struct shared_info xen_dummy_shared_info
;
70 void *xen_initial_gdt
;
73 * Point at some empty memory to start with. We map the real shared_info
74 * page as soon as fixmap is up and running.
76 struct shared_info
*HYPERVISOR_shared_info
= (void *)&xen_dummy_shared_info
;
79 * Flag to determine whether vcpu info placement is available on all
80 * VCPUs. We assume it is to start with, and then set it to zero on
81 * the first failure. This is because it can succeed on some VCPUs
82 * and not others, since it can involve hypervisor memory allocation,
83 * or because the guest failed to guarantee all the appropriate
84 * constraints on all VCPUs (ie buffer can't cross a page boundary).
86 * Note that any particular CPU may be using a placed vcpu structure,
87 * but we can only optimise if the all are.
89 * 0: not available, 1: available
91 static int have_vcpu_info_placement
= 1;
93 static void xen_vcpu_setup(int cpu
)
95 struct vcpu_register_vcpu_info info
;
97 struct vcpu_info
*vcpup
;
99 BUG_ON(HYPERVISOR_shared_info
== &xen_dummy_shared_info
);
100 per_cpu(xen_vcpu
, cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
102 if (!have_vcpu_info_placement
)
103 return; /* already tested, not available */
105 vcpup
= &per_cpu(xen_vcpu_info
, cpu
);
107 info
.mfn
= arbitrary_virt_to_mfn(vcpup
);
108 info
.offset
= offset_in_page(vcpup
);
110 printk(KERN_DEBUG
"trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
111 cpu
, vcpup
, info
.mfn
, info
.offset
);
113 /* Check to see if the hypervisor will put the vcpu_info
114 structure where we want it, which allows direct access via
115 a percpu-variable. */
116 err
= HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info
, cpu
, &info
);
119 printk(KERN_DEBUG
"register_vcpu_info failed: err=%d\n", err
);
120 have_vcpu_info_placement
= 0;
122 /* This cpu is using the registered vcpu info, even if
123 later ones fail to. */
124 per_cpu(xen_vcpu
, cpu
) = vcpup
;
126 printk(KERN_DEBUG
"cpu %d using vcpu_info at %p\n",
132 * On restore, set the vcpu placement up again.
133 * If it fails, then we're in a bad state, since
134 * we can't back out from using it...
136 void xen_vcpu_restore(void)
138 if (have_vcpu_info_placement
) {
141 for_each_online_cpu(cpu
) {
142 bool other_cpu
= (cpu
!= smp_processor_id());
145 HYPERVISOR_vcpu_op(VCPUOP_down
, cpu
, NULL
))
151 HYPERVISOR_vcpu_op(VCPUOP_up
, cpu
, NULL
))
155 BUG_ON(!have_vcpu_info_placement
);
159 static void __init
xen_banner(void)
161 unsigned version
= HYPERVISOR_xen_version(XENVER_version
, NULL
);
162 struct xen_extraversion extra
;
163 HYPERVISOR_xen_version(XENVER_extraversion
, &extra
);
165 printk(KERN_INFO
"Booting paravirtualized kernel on %s\n",
167 printk(KERN_INFO
"Xen version: %d.%d%s%s\n",
168 version
>> 16, version
& 0xffff, extra
.extraversion
,
169 xen_feature(XENFEAT_mmu_pt_update_preserve_ad
) ? " (preserve-AD)" : "");
172 static __read_mostly
unsigned int cpuid_leaf1_edx_mask
= ~0;
173 static __read_mostly
unsigned int cpuid_leaf1_ecx_mask
= ~0;
175 static void xen_cpuid(unsigned int *ax
, unsigned int *bx
,
176 unsigned int *cx
, unsigned int *dx
)
178 unsigned maskecx
= ~0;
179 unsigned maskedx
= ~0;
182 * Mask out inconvenient features, to try and disable as many
183 * unsupported kernel subsystems as possible.
186 maskecx
= cpuid_leaf1_ecx_mask
;
187 maskedx
= cpuid_leaf1_edx_mask
;
190 asm(XEN_EMULATE_PREFIX
"cpuid"
195 : "0" (*ax
), "2" (*cx
));
201 static __init
void xen_init_cpuid_mask(void)
203 unsigned int ax
, bx
, cx
, dx
;
205 cpuid_leaf1_edx_mask
=
206 ~((1 << X86_FEATURE_MCE
) | /* disable MCE */
207 (1 << X86_FEATURE_MCA
) | /* disable MCA */
208 (1 << X86_FEATURE_ACC
)); /* thermal monitoring */
210 if (!xen_initial_domain())
211 cpuid_leaf1_edx_mask
&=
212 ~((1 << X86_FEATURE_APIC
) | /* disable local APIC */
213 (1 << X86_FEATURE_ACPI
)); /* disable ACPI */
216 xen_cpuid(&ax
, &bx
, &cx
, &dx
);
218 /* cpuid claims we support xsave; try enabling it to see what happens */
219 if (cx
& (1 << (X86_FEATURE_XSAVE
% 32))) {
222 set_in_cr4(X86_CR4_OSXSAVE
);
226 if ((cr4
& X86_CR4_OSXSAVE
) == 0)
227 cpuid_leaf1_ecx_mask
&= ~(1 << (X86_FEATURE_XSAVE
% 32));
229 clear_in_cr4(X86_CR4_OSXSAVE
);
233 static void xen_set_debugreg(int reg
, unsigned long val
)
235 HYPERVISOR_set_debugreg(reg
, val
);
238 static unsigned long xen_get_debugreg(int reg
)
240 return HYPERVISOR_get_debugreg(reg
);
243 void xen_leave_lazy(void)
245 paravirt_leave_lazy(paravirt_get_lazy_mode());
249 static unsigned long xen_store_tr(void)
255 * Set the page permissions for a particular virtual address. If the
256 * address is a vmalloc mapping (or other non-linear mapping), then
257 * find the linear mapping of the page and also set its protections to
260 static void set_aliased_prot(void *v
, pgprot_t prot
)
268 ptep
= lookup_address((unsigned long)v
, &level
);
269 BUG_ON(ptep
== NULL
);
271 pfn
= pte_pfn(*ptep
);
272 page
= pfn_to_page(pfn
);
274 pte
= pfn_pte(pfn
, prot
);
276 if (HYPERVISOR_update_va_mapping((unsigned long)v
, pte
, 0))
279 if (!PageHighMem(page
)) {
280 void *av
= __va(PFN_PHYS(pfn
));
283 if (HYPERVISOR_update_va_mapping((unsigned long)av
, pte
, 0))
289 static void xen_alloc_ldt(struct desc_struct
*ldt
, unsigned entries
)
291 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
294 for(i
= 0; i
< entries
; i
+= entries_per_page
)
295 set_aliased_prot(ldt
+ i
, PAGE_KERNEL_RO
);
298 static void xen_free_ldt(struct desc_struct
*ldt
, unsigned entries
)
300 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
303 for(i
= 0; i
< entries
; i
+= entries_per_page
)
304 set_aliased_prot(ldt
+ i
, PAGE_KERNEL
);
307 static void xen_set_ldt(const void *addr
, unsigned entries
)
309 struct mmuext_op
*op
;
310 struct multicall_space mcs
= xen_mc_entry(sizeof(*op
));
313 op
->cmd
= MMUEXT_SET_LDT
;
314 op
->arg1
.linear_addr
= (unsigned long)addr
;
315 op
->arg2
.nr_ents
= entries
;
317 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
319 xen_mc_issue(PARAVIRT_LAZY_CPU
);
322 static void xen_load_gdt(const struct desc_ptr
*dtr
)
324 unsigned long va
= dtr
->address
;
325 unsigned int size
= dtr
->size
+ 1;
326 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
327 unsigned long frames
[pages
];
330 /* A GDT can be up to 64k in size, which corresponds to 8192
331 8-byte entries, or 16 4k pages.. */
333 BUG_ON(size
> 65536);
334 BUG_ON(va
& ~PAGE_MASK
);
336 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
338 pte_t
*ptep
= lookup_address(va
, &level
);
339 unsigned long pfn
, mfn
;
342 BUG_ON(ptep
== NULL
);
344 pfn
= pte_pfn(*ptep
);
345 mfn
= pfn_to_mfn(pfn
);
346 virt
= __va(PFN_PHYS(pfn
));
350 make_lowmem_page_readonly((void *)va
);
351 make_lowmem_page_readonly(virt
);
354 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
358 static void load_TLS_descriptor(struct thread_struct
*t
,
359 unsigned int cpu
, unsigned int i
)
361 struct desc_struct
*gdt
= get_cpu_gdt_table(cpu
);
362 xmaddr_t maddr
= arbitrary_virt_to_machine(&gdt
[GDT_ENTRY_TLS_MIN
+i
]);
363 struct multicall_space mc
= __xen_mc_entry(0);
365 MULTI_update_descriptor(mc
.mc
, maddr
.maddr
, t
->tls_array
[i
]);
368 static void xen_load_tls(struct thread_struct
*t
, unsigned int cpu
)
371 * XXX sleazy hack: If we're being called in a lazy-cpu zone
372 * and lazy gs handling is enabled, it means we're in a
373 * context switch, and %gs has just been saved. This means we
374 * can zero it out to prevent faults on exit from the
375 * hypervisor if the next process has no %gs. Either way, it
376 * has been saved, and the new value will get loaded properly.
377 * This will go away as soon as Xen has been modified to not
378 * save/restore %gs for normal hypercalls.
380 * On x86_64, this hack is not used for %gs, because gs points
381 * to KERNEL_GS_BASE (and uses it for PDA references), so we
382 * must not zero %gs on x86_64
384 * For x86_64, we need to zero %fs, otherwise we may get an
385 * exception between the new %fs descriptor being loaded and
386 * %fs being effectively cleared at __switch_to().
388 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU
) {
398 load_TLS_descriptor(t
, cpu
, 0);
399 load_TLS_descriptor(t
, cpu
, 1);
400 load_TLS_descriptor(t
, cpu
, 2);
402 xen_mc_issue(PARAVIRT_LAZY_CPU
);
406 static void xen_load_gs_index(unsigned int idx
)
408 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL
, idx
))
413 static void xen_write_ldt_entry(struct desc_struct
*dt
, int entrynum
,
416 xmaddr_t mach_lp
= arbitrary_virt_to_machine(&dt
[entrynum
]);
417 u64 entry
= *(u64
*)ptr
;
422 if (HYPERVISOR_update_descriptor(mach_lp
.maddr
, entry
))
428 static int cvt_gate_to_trap(int vector
, const gate_desc
*val
,
429 struct trap_info
*info
)
431 if (val
->type
!= GATE_TRAP
&& val
->type
!= GATE_INTERRUPT
)
434 info
->vector
= vector
;
435 info
->address
= gate_offset(*val
);
436 info
->cs
= gate_segment(*val
);
437 info
->flags
= val
->dpl
;
438 /* interrupt gates clear IF */
439 if (val
->type
== GATE_INTERRUPT
)
440 info
->flags
|= 1 << 2;
445 /* Locations of each CPU's IDT */
446 static DEFINE_PER_CPU(struct desc_ptr
, idt_desc
);
448 /* Set an IDT entry. If the entry is part of the current IDT, then
450 static void xen_write_idt_entry(gate_desc
*dt
, int entrynum
, const gate_desc
*g
)
452 unsigned long p
= (unsigned long)&dt
[entrynum
];
453 unsigned long start
, end
;
457 start
= __get_cpu_var(idt_desc
).address
;
458 end
= start
+ __get_cpu_var(idt_desc
).size
+ 1;
462 native_write_idt_entry(dt
, entrynum
, g
);
464 if (p
>= start
&& (p
+ 8) <= end
) {
465 struct trap_info info
[2];
469 if (cvt_gate_to_trap(entrynum
, g
, &info
[0]))
470 if (HYPERVISOR_set_trap_table(info
))
477 static void xen_convert_trap_info(const struct desc_ptr
*desc
,
478 struct trap_info
*traps
)
480 unsigned in
, out
, count
;
482 count
= (desc
->size
+1) / sizeof(gate_desc
);
485 for (in
= out
= 0; in
< count
; in
++) {
486 gate_desc
*entry
= (gate_desc
*)(desc
->address
) + in
;
488 if (cvt_gate_to_trap(in
, entry
, &traps
[out
]))
491 traps
[out
].address
= 0;
494 void xen_copy_trap_info(struct trap_info
*traps
)
496 const struct desc_ptr
*desc
= &__get_cpu_var(idt_desc
);
498 xen_convert_trap_info(desc
, traps
);
501 /* Load a new IDT into Xen. In principle this can be per-CPU, so we
502 hold a spinlock to protect the static traps[] array (static because
503 it avoids allocation, and saves stack space). */
504 static void xen_load_idt(const struct desc_ptr
*desc
)
506 static DEFINE_SPINLOCK(lock
);
507 static struct trap_info traps
[257];
511 __get_cpu_var(idt_desc
) = *desc
;
513 xen_convert_trap_info(desc
, traps
);
516 if (HYPERVISOR_set_trap_table(traps
))
522 /* Write a GDT descriptor entry. Ignore LDT descriptors, since
523 they're handled differently. */
524 static void xen_write_gdt_entry(struct desc_struct
*dt
, int entry
,
525 const void *desc
, int type
)
536 xmaddr_t maddr
= arbitrary_virt_to_machine(&dt
[entry
]);
539 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
548 static void xen_load_sp0(struct tss_struct
*tss
,
549 struct thread_struct
*thread
)
551 struct multicall_space mcs
= xen_mc_entry(0);
552 MULTI_stack_switch(mcs
.mc
, __KERNEL_DS
, thread
->sp0
);
553 xen_mc_issue(PARAVIRT_LAZY_CPU
);
556 static void xen_set_iopl_mask(unsigned mask
)
558 struct physdev_set_iopl set_iopl
;
560 /* Force the change at ring 0. */
561 set_iopl
.iopl
= (mask
== 0) ? 1 : (mask
>> 12) & 3;
562 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
565 static void xen_io_delay(void)
569 #ifdef CONFIG_X86_LOCAL_APIC
570 static u32
xen_apic_read(u32 reg
)
575 static void xen_apic_write(u32 reg
, u32 val
)
577 /* Warn to see if there's any stray references */
581 static u64
xen_apic_icr_read(void)
586 static void xen_apic_icr_write(u32 low
, u32 id
)
588 /* Warn to see if there's any stray references */
592 static void xen_apic_wait_icr_idle(void)
597 static u32
xen_safe_apic_wait_icr_idle(void)
602 static void set_xen_basic_apic_ops(void)
604 apic
->read
= xen_apic_read
;
605 apic
->write
= xen_apic_write
;
606 apic
->icr_read
= xen_apic_icr_read
;
607 apic
->icr_write
= xen_apic_icr_write
;
608 apic
->wait_icr_idle
= xen_apic_wait_icr_idle
;
609 apic
->safe_wait_icr_idle
= xen_safe_apic_wait_icr_idle
;
615 static void xen_clts(void)
617 struct multicall_space mcs
;
619 mcs
= xen_mc_entry(0);
621 MULTI_fpu_taskswitch(mcs
.mc
, 0);
623 xen_mc_issue(PARAVIRT_LAZY_CPU
);
626 static void xen_write_cr0(unsigned long cr0
)
628 struct multicall_space mcs
;
630 /* Only pay attention to cr0.TS; everything else is
632 mcs
= xen_mc_entry(0);
634 MULTI_fpu_taskswitch(mcs
.mc
, (cr0
& X86_CR0_TS
) != 0);
636 xen_mc_issue(PARAVIRT_LAZY_CPU
);
639 static void xen_write_cr4(unsigned long cr4
)
644 native_write_cr4(cr4
);
647 static int xen_write_msr_safe(unsigned int msr
, unsigned low
, unsigned high
)
658 case MSR_FS_BASE
: which
= SEGBASE_FS
; goto set
;
659 case MSR_KERNEL_GS_BASE
: which
= SEGBASE_GS_USER
; goto set
;
660 case MSR_GS_BASE
: which
= SEGBASE_GS_KERNEL
; goto set
;
663 base
= ((u64
)high
<< 32) | low
;
664 if (HYPERVISOR_set_segment_base(which
, base
) != 0)
672 case MSR_SYSCALL_MASK
:
673 case MSR_IA32_SYSENTER_CS
:
674 case MSR_IA32_SYSENTER_ESP
:
675 case MSR_IA32_SYSENTER_EIP
:
676 /* Fast syscall setup is all done in hypercalls, so
677 these are all ignored. Stub them out here to stop
678 Xen console noise. */
682 ret
= native_write_msr_safe(msr
, low
, high
);
688 void xen_setup_shared_info(void)
690 if (!xen_feature(XENFEAT_auto_translated_physmap
)) {
691 set_fixmap(FIX_PARAVIRT_BOOTMAP
,
692 xen_start_info
->shared_info
);
694 HYPERVISOR_shared_info
=
695 (struct shared_info
*)fix_to_virt(FIX_PARAVIRT_BOOTMAP
);
697 HYPERVISOR_shared_info
=
698 (struct shared_info
*)__va(xen_start_info
->shared_info
);
701 /* In UP this is as good a place as any to set up shared info */
702 xen_setup_vcpu_info_placement();
705 xen_setup_mfn_list_list();
708 /* This is called once we have the cpu_possible_map */
709 void xen_setup_vcpu_info_placement(void)
713 for_each_possible_cpu(cpu
)
716 /* xen_vcpu_setup managed to place the vcpu_info within the
717 percpu area for all cpus, so make use of it */
718 if (have_vcpu_info_placement
) {
719 printk(KERN_INFO
"Xen: using vcpu_info placement\n");
721 pv_irq_ops
.save_fl
= __PV_IS_CALLEE_SAVE(xen_save_fl_direct
);
722 pv_irq_ops
.restore_fl
= __PV_IS_CALLEE_SAVE(xen_restore_fl_direct
);
723 pv_irq_ops
.irq_disable
= __PV_IS_CALLEE_SAVE(xen_irq_disable_direct
);
724 pv_irq_ops
.irq_enable
= __PV_IS_CALLEE_SAVE(xen_irq_enable_direct
);
725 pv_mmu_ops
.read_cr2
= xen_read_cr2_direct
;
729 static unsigned xen_patch(u8 type
, u16 clobbers
, void *insnbuf
,
730 unsigned long addr
, unsigned len
)
732 char *start
, *end
, *reloc
;
735 start
= end
= reloc
= NULL
;
737 #define SITE(op, x) \
738 case PARAVIRT_PATCH(op.x): \
739 if (have_vcpu_info_placement) { \
740 start = (char *)xen_##x##_direct; \
741 end = xen_##x##_direct_end; \
742 reloc = xen_##x##_direct_reloc; \
747 SITE(pv_irq_ops
, irq_enable
);
748 SITE(pv_irq_ops
, irq_disable
);
749 SITE(pv_irq_ops
, save_fl
);
750 SITE(pv_irq_ops
, restore_fl
);
754 if (start
== NULL
|| (end
-start
) > len
)
757 ret
= paravirt_patch_insns(insnbuf
, len
, start
, end
);
759 /* Note: because reloc is assigned from something that
760 appears to be an array, gcc assumes it's non-null,
761 but doesn't know its relationship with start and
763 if (reloc
> start
&& reloc
< end
) {
764 int reloc_off
= reloc
- start
;
765 long *relocp
= (long *)(insnbuf
+ reloc_off
);
766 long delta
= start
- (char *)addr
;
774 ret
= paravirt_patch_default(type
, clobbers
, insnbuf
,
782 static const struct pv_info xen_info __initdata
= {
783 .paravirt_enabled
= 1,
784 .shared_kernel_pmd
= 0,
789 static const struct pv_init_ops xen_init_ops __initdata
= {
792 .banner
= xen_banner
,
793 .memory_setup
= xen_memory_setup
,
794 .arch_setup
= xen_arch_setup
,
795 .post_allocator_init
= xen_post_allocator_init
,
798 static const struct pv_time_ops xen_time_ops __initdata
= {
799 .time_init
= xen_time_init
,
801 .set_wallclock
= xen_set_wallclock
,
802 .get_wallclock
= xen_get_wallclock
,
803 .get_tsc_khz
= xen_tsc_khz
,
804 .sched_clock
= xen_sched_clock
,
807 static const struct pv_cpu_ops xen_cpu_ops __initdata
= {
810 .set_debugreg
= xen_set_debugreg
,
811 .get_debugreg
= xen_get_debugreg
,
815 .read_cr0
= native_read_cr0
,
816 .write_cr0
= xen_write_cr0
,
818 .read_cr4
= native_read_cr4
,
819 .read_cr4_safe
= native_read_cr4_safe
,
820 .write_cr4
= xen_write_cr4
,
822 .wbinvd
= native_wbinvd
,
824 .read_msr
= native_read_msr_safe
,
825 .write_msr
= xen_write_msr_safe
,
826 .read_tsc
= native_read_tsc
,
827 .read_pmc
= native_read_pmc
,
830 .irq_enable_sysexit
= xen_sysexit
,
832 .usergs_sysret32
= xen_sysret32
,
833 .usergs_sysret64
= xen_sysret64
,
836 .load_tr_desc
= paravirt_nop
,
837 .set_ldt
= xen_set_ldt
,
838 .load_gdt
= xen_load_gdt
,
839 .load_idt
= xen_load_idt
,
840 .load_tls
= xen_load_tls
,
842 .load_gs_index
= xen_load_gs_index
,
845 .alloc_ldt
= xen_alloc_ldt
,
846 .free_ldt
= xen_free_ldt
,
848 .store_gdt
= native_store_gdt
,
849 .store_idt
= native_store_idt
,
850 .store_tr
= xen_store_tr
,
852 .write_ldt_entry
= xen_write_ldt_entry
,
853 .write_gdt_entry
= xen_write_gdt_entry
,
854 .write_idt_entry
= xen_write_idt_entry
,
855 .load_sp0
= xen_load_sp0
,
857 .set_iopl_mask
= xen_set_iopl_mask
,
858 .io_delay
= xen_io_delay
,
860 /* Xen takes care of %gs when switching to usermode for us */
861 .swapgs
= paravirt_nop
,
864 .enter
= paravirt_enter_lazy_cpu
,
865 .leave
= xen_leave_lazy
,
869 static const struct pv_apic_ops xen_apic_ops __initdata
= {
870 #ifdef CONFIG_X86_LOCAL_APIC
871 .setup_boot_clock
= paravirt_nop
,
872 .setup_secondary_clock
= paravirt_nop
,
873 .startup_ipi_hook
= paravirt_nop
,
877 static void xen_reboot(int reason
)
879 struct sched_shutdown r
= { .reason
= reason
};
885 if (HYPERVISOR_sched_op(SCHEDOP_shutdown
, &r
))
889 static void xen_restart(char *msg
)
891 xen_reboot(SHUTDOWN_reboot
);
894 static void xen_emergency_restart(void)
896 xen_reboot(SHUTDOWN_reboot
);
899 static void xen_machine_halt(void)
901 xen_reboot(SHUTDOWN_poweroff
);
904 static void xen_crash_shutdown(struct pt_regs
*regs
)
906 xen_reboot(SHUTDOWN_crash
);
909 static const struct machine_ops __initdata xen_machine_ops
= {
910 .restart
= xen_restart
,
911 .halt
= xen_machine_halt
,
912 .power_off
= xen_machine_halt
,
913 .shutdown
= xen_machine_halt
,
914 .crash_shutdown
= xen_crash_shutdown
,
915 .emergency_restart
= xen_emergency_restart
,
918 /* First C function to be called on Xen boot */
919 asmlinkage
void __init
xen_start_kernel(void)
926 xen_domain_type
= XEN_PV_DOMAIN
;
928 BUG_ON(memcmp(xen_start_info
->magic
, "xen-3", 5) != 0);
930 xen_setup_features();
932 /* Install Xen paravirt ops */
934 pv_init_ops
= xen_init_ops
;
935 pv_time_ops
= xen_time_ops
;
936 pv_cpu_ops
= xen_cpu_ops
;
937 pv_apic_ops
= xen_apic_ops
;
938 pv_mmu_ops
= xen_mmu_ops
;
942 xen_init_cpuid_mask();
944 #ifdef CONFIG_X86_LOCAL_APIC
946 * set up the basic apic ops.
948 set_xen_basic_apic_ops();
951 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad
)) {
952 pv_mmu_ops
.ptep_modify_prot_start
= xen_ptep_modify_prot_start
;
953 pv_mmu_ops
.ptep_modify_prot_commit
= xen_ptep_modify_prot_commit
;
956 machine_ops
= xen_machine_ops
;
960 * Setup percpu state. We only need to do this for 64-bit
961 * because 32-bit already has %fs set properly.
963 load_percpu_segment(0);
966 * The only reliable way to retain the initial address of the
967 * percpu gdt_page is to remember it here, so we can go and
968 * mark it RW later, when the initial percpu area is freed.
970 xen_initial_gdt
= &per_cpu(gdt_page
, 0);
975 if (!xen_feature(XENFEAT_auto_translated_physmap
))
976 xen_build_dynamic_phys_to_machine();
978 pgd
= (pgd_t
*)xen_start_info
->pt_base
;
980 /* Prevent unwanted bits from being set in PTEs. */
981 __supported_pte_mask
&= ~_PAGE_GLOBAL
;
982 if (!xen_initial_domain())
983 __supported_pte_mask
&= ~(_PAGE_PWT
| _PAGE_PCD
);
986 /* Work out if we support NX */
990 /* Don't do the full vcpu_info placement stuff until we have a
991 possible map and a non-dummy shared_info. */
992 per_cpu(xen_vcpu
, 0) = &HYPERVISOR_shared_info
->vcpu_info
[0];
995 early_boot_irqs_off();
997 xen_raw_console_write("mapping kernel into physical memory\n");
998 pgd
= xen_setup_kernel_pagetable(pgd
, xen_start_info
->nr_pages
);
1002 /* keep using Xen gdt for now; no urgent need to change it */
1004 pv_info
.kernel_rpl
= 1;
1005 if (xen_feature(XENFEAT_supervisor_mode_kernel
))
1006 pv_info
.kernel_rpl
= 0;
1008 /* set the limit of our address space */
1011 #ifdef CONFIG_X86_32
1012 /* set up basic CPUID stuff */
1013 cpu_detect(&new_cpu_data
);
1014 new_cpu_data
.hard_math
= 1;
1015 new_cpu_data
.x86_capability
[0] = cpuid_edx(1);
1018 /* Poke various useful things into boot_params */
1019 boot_params
.hdr
.type_of_loader
= (9 << 4) | 0;
1020 boot_params
.hdr
.ramdisk_image
= xen_start_info
->mod_start
1021 ? __pa(xen_start_info
->mod_start
) : 0;
1022 boot_params
.hdr
.ramdisk_size
= xen_start_info
->mod_len
;
1023 boot_params
.hdr
.cmd_line_ptr
= __pa(xen_start_info
->cmd_line
);
1025 if (!xen_initial_domain()) {
1026 add_preferred_console("xenboot", 0, NULL
);
1027 add_preferred_console("tty", 0, NULL
);
1028 add_preferred_console("hvc", 0, NULL
);
1031 xen_raw_console_write("about to get started...\n");
1033 /* Start the world */
1034 #ifdef CONFIG_X86_32
1035 i386_start_kernel();
1037 x86_64_start_reservations((char *)__pa_symbol(&boot_params
));