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/kprobes.h>
24 #include <linux/bootmem.h>
25 #include <linux/module.h>
27 #include <linux/page-flags.h>
28 #include <linux/highmem.h>
29 #include <linux/console.h>
30 #include <linux/pci.h>
33 #include <xen/interface/xen.h>
34 #include <xen/interface/version.h>
35 #include <xen/interface/physdev.h>
36 #include <xen/interface/vcpu.h>
37 #include <xen/features.h>
39 #include <xen/hvc-console.h>
41 #include <asm/paravirt.h>
44 #include <asm/xen/hypercall.h>
45 #include <asm/xen/hypervisor.h>
46 #include <asm/fixmap.h>
47 #include <asm/processor.h>
48 #include <asm/proto.h>
49 #include <asm/msr-index.h>
50 #include <asm/traps.h>
51 #include <asm/setup.h>
53 #include <asm/pgtable.h>
54 #include <asm/tlbflush.h>
55 #include <asm/reboot.h>
56 #include <asm/stackprotector.h>
60 #include "multicalls.h"
62 EXPORT_SYMBOL_GPL(hypercall_page
);
64 DEFINE_PER_CPU(struct vcpu_info
*, xen_vcpu
);
65 DEFINE_PER_CPU(struct vcpu_info
, xen_vcpu_info
);
67 enum xen_domain_type xen_domain_type
= XEN_NATIVE
;
68 EXPORT_SYMBOL_GPL(xen_domain_type
);
70 struct start_info
*xen_start_info
;
71 EXPORT_SYMBOL_GPL(xen_start_info
);
73 struct shared_info xen_dummy_shared_info
;
75 void *xen_initial_gdt
;
78 * Point at some empty memory to start with. We map the real shared_info
79 * page as soon as fixmap is up and running.
81 struct shared_info
*HYPERVISOR_shared_info
= (void *)&xen_dummy_shared_info
;
84 * Flag to determine whether vcpu info placement is available on all
85 * VCPUs. We assume it is to start with, and then set it to zero on
86 * the first failure. This is because it can succeed on some VCPUs
87 * and not others, since it can involve hypervisor memory allocation,
88 * or because the guest failed to guarantee all the appropriate
89 * constraints on all VCPUs (ie buffer can't cross a page boundary).
91 * Note that any particular CPU may be using a placed vcpu structure,
92 * but we can only optimise if the all are.
94 * 0: not available, 1: available
96 static int have_vcpu_info_placement
= 1;
98 static void xen_vcpu_setup(int cpu
)
100 struct vcpu_register_vcpu_info info
;
102 struct vcpu_info
*vcpup
;
104 BUG_ON(HYPERVISOR_shared_info
== &xen_dummy_shared_info
);
105 per_cpu(xen_vcpu
, cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
107 if (!have_vcpu_info_placement
)
108 return; /* already tested, not available */
110 vcpup
= &per_cpu(xen_vcpu_info
, cpu
);
112 info
.mfn
= arbitrary_virt_to_mfn(vcpup
);
113 info
.offset
= offset_in_page(vcpup
);
115 printk(KERN_DEBUG
"trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
116 cpu
, vcpup
, info
.mfn
, info
.offset
);
118 /* Check to see if the hypervisor will put the vcpu_info
119 structure where we want it, which allows direct access via
120 a percpu-variable. */
121 err
= HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info
, cpu
, &info
);
124 printk(KERN_DEBUG
"register_vcpu_info failed: err=%d\n", err
);
125 have_vcpu_info_placement
= 0;
127 /* This cpu is using the registered vcpu info, even if
128 later ones fail to. */
129 per_cpu(xen_vcpu
, cpu
) = vcpup
;
131 printk(KERN_DEBUG
"cpu %d using vcpu_info at %p\n",
137 * On restore, set the vcpu placement up again.
138 * If it fails, then we're in a bad state, since
139 * we can't back out from using it...
141 void xen_vcpu_restore(void)
145 for_each_online_cpu(cpu
) {
146 bool other_cpu
= (cpu
!= smp_processor_id());
149 HYPERVISOR_vcpu_op(VCPUOP_down
, cpu
, NULL
))
152 xen_setup_runstate_info(cpu
);
154 if (have_vcpu_info_placement
)
158 HYPERVISOR_vcpu_op(VCPUOP_up
, cpu
, NULL
))
163 static void __init
xen_banner(void)
165 unsigned version
= HYPERVISOR_xen_version(XENVER_version
, NULL
);
166 struct xen_extraversion extra
;
167 HYPERVISOR_xen_version(XENVER_extraversion
, &extra
);
169 printk(KERN_INFO
"Booting paravirtualized kernel on %s\n",
171 printk(KERN_INFO
"Xen version: %d.%d%s%s\n",
172 version
>> 16, version
& 0xffff, extra
.extraversion
,
173 xen_feature(XENFEAT_mmu_pt_update_preserve_ad
) ? " (preserve-AD)" : "");
176 static __read_mostly
unsigned int cpuid_leaf1_edx_mask
= ~0;
177 static __read_mostly
unsigned int cpuid_leaf1_ecx_mask
= ~0;
179 static void xen_cpuid(unsigned int *ax
, unsigned int *bx
,
180 unsigned int *cx
, unsigned int *dx
)
182 unsigned maskebx
= ~0;
183 unsigned maskecx
= ~0;
184 unsigned maskedx
= ~0;
187 * Mask out inconvenient features, to try and disable as many
188 * unsupported kernel subsystems as possible.
192 maskecx
= cpuid_leaf1_ecx_mask
;
193 maskedx
= cpuid_leaf1_edx_mask
;
197 /* Suppress extended topology stuff */
202 asm(XEN_EMULATE_PREFIX
"cpuid"
207 : "0" (*ax
), "2" (*cx
));
214 static __init
void xen_init_cpuid_mask(void)
216 unsigned int ax
, bx
, cx
, dx
;
218 cpuid_leaf1_edx_mask
=
219 ~((1 << X86_FEATURE_MCE
) | /* disable MCE */
220 (1 << X86_FEATURE_MCA
) | /* disable MCA */
221 (1 << X86_FEATURE_ACC
)); /* thermal monitoring */
223 if (!xen_initial_domain())
224 cpuid_leaf1_edx_mask
&=
225 ~((1 << X86_FEATURE_APIC
) | /* disable local APIC */
226 (1 << X86_FEATURE_ACPI
)); /* disable ACPI */
230 xen_cpuid(&ax
, &bx
, &cx
, &dx
);
232 /* cpuid claims we support xsave; try enabling it to see what happens */
233 if (cx
& (1 << (X86_FEATURE_XSAVE
% 32))) {
236 set_in_cr4(X86_CR4_OSXSAVE
);
240 if ((cr4
& X86_CR4_OSXSAVE
) == 0)
241 cpuid_leaf1_ecx_mask
&= ~(1 << (X86_FEATURE_XSAVE
% 32));
243 clear_in_cr4(X86_CR4_OSXSAVE
);
247 static void xen_set_debugreg(int reg
, unsigned long val
)
249 HYPERVISOR_set_debugreg(reg
, val
);
252 static unsigned long xen_get_debugreg(int reg
)
254 return HYPERVISOR_get_debugreg(reg
);
257 static void xen_end_context_switch(struct task_struct
*next
)
260 paravirt_end_context_switch(next
);
263 static unsigned long xen_store_tr(void)
269 * Set the page permissions for a particular virtual address. If the
270 * address is a vmalloc mapping (or other non-linear mapping), then
271 * find the linear mapping of the page and also set its protections to
274 static void set_aliased_prot(void *v
, pgprot_t prot
)
282 ptep
= lookup_address((unsigned long)v
, &level
);
283 BUG_ON(ptep
== NULL
);
285 pfn
= pte_pfn(*ptep
);
286 page
= pfn_to_page(pfn
);
288 pte
= pfn_pte(pfn
, prot
);
290 if (HYPERVISOR_update_va_mapping((unsigned long)v
, pte
, 0))
293 if (!PageHighMem(page
)) {
294 void *av
= __va(PFN_PHYS(pfn
));
297 if (HYPERVISOR_update_va_mapping((unsigned long)av
, pte
, 0))
303 static void xen_alloc_ldt(struct desc_struct
*ldt
, unsigned entries
)
305 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
308 for(i
= 0; i
< entries
; i
+= entries_per_page
)
309 set_aliased_prot(ldt
+ i
, PAGE_KERNEL_RO
);
312 static void xen_free_ldt(struct desc_struct
*ldt
, unsigned entries
)
314 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
317 for(i
= 0; i
< entries
; i
+= entries_per_page
)
318 set_aliased_prot(ldt
+ i
, PAGE_KERNEL
);
321 static void xen_set_ldt(const void *addr
, unsigned entries
)
323 struct mmuext_op
*op
;
324 struct multicall_space mcs
= xen_mc_entry(sizeof(*op
));
327 op
->cmd
= MMUEXT_SET_LDT
;
328 op
->arg1
.linear_addr
= (unsigned long)addr
;
329 op
->arg2
.nr_ents
= entries
;
331 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
333 xen_mc_issue(PARAVIRT_LAZY_CPU
);
336 static void xen_load_gdt(const struct desc_ptr
*dtr
)
338 unsigned long va
= dtr
->address
;
339 unsigned int size
= dtr
->size
+ 1;
340 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
341 unsigned long frames
[pages
];
345 * A GDT can be up to 64k in size, which corresponds to 8192
346 * 8-byte entries, or 16 4k pages..
349 BUG_ON(size
> 65536);
350 BUG_ON(va
& ~PAGE_MASK
);
352 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
355 unsigned long pfn
, mfn
;
359 * The GDT is per-cpu and is in the percpu data area.
360 * That can be virtually mapped, so we need to do a
361 * page-walk to get the underlying MFN for the
362 * hypercall. The page can also be in the kernel's
363 * linear range, so we need to RO that mapping too.
365 ptep
= lookup_address(va
, &level
);
366 BUG_ON(ptep
== NULL
);
368 pfn
= pte_pfn(*ptep
);
369 mfn
= pfn_to_mfn(pfn
);
370 virt
= __va(PFN_PHYS(pfn
));
374 make_lowmem_page_readonly((void *)va
);
375 make_lowmem_page_readonly(virt
);
378 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
383 * load_gdt for early boot, when the gdt is only mapped once
385 static __init
void xen_load_gdt_boot(const struct desc_ptr
*dtr
)
387 unsigned long va
= dtr
->address
;
388 unsigned int size
= dtr
->size
+ 1;
389 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
390 unsigned long frames
[pages
];
394 * A GDT can be up to 64k in size, which corresponds to 8192
395 * 8-byte entries, or 16 4k pages..
398 BUG_ON(size
> 65536);
399 BUG_ON(va
& ~PAGE_MASK
);
401 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
403 unsigned long pfn
, mfn
;
405 pfn
= virt_to_pfn(va
);
406 mfn
= pfn_to_mfn(pfn
);
408 pte
= pfn_pte(pfn
, PAGE_KERNEL_RO
);
410 if (HYPERVISOR_update_va_mapping((unsigned long)va
, pte
, 0))
416 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
420 static void load_TLS_descriptor(struct thread_struct
*t
,
421 unsigned int cpu
, unsigned int i
)
423 struct desc_struct
*gdt
= get_cpu_gdt_table(cpu
);
424 xmaddr_t maddr
= arbitrary_virt_to_machine(&gdt
[GDT_ENTRY_TLS_MIN
+i
]);
425 struct multicall_space mc
= __xen_mc_entry(0);
427 MULTI_update_descriptor(mc
.mc
, maddr
.maddr
, t
->tls_array
[i
]);
430 static void xen_load_tls(struct thread_struct
*t
, unsigned int cpu
)
433 * XXX sleazy hack: If we're being called in a lazy-cpu zone
434 * and lazy gs handling is enabled, it means we're in a
435 * context switch, and %gs has just been saved. This means we
436 * can zero it out to prevent faults on exit from the
437 * hypervisor if the next process has no %gs. Either way, it
438 * has been saved, and the new value will get loaded properly.
439 * This will go away as soon as Xen has been modified to not
440 * save/restore %gs for normal hypercalls.
442 * On x86_64, this hack is not used for %gs, because gs points
443 * to KERNEL_GS_BASE (and uses it for PDA references), so we
444 * must not zero %gs on x86_64
446 * For x86_64, we need to zero %fs, otherwise we may get an
447 * exception between the new %fs descriptor being loaded and
448 * %fs being effectively cleared at __switch_to().
450 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU
) {
460 load_TLS_descriptor(t
, cpu
, 0);
461 load_TLS_descriptor(t
, cpu
, 1);
462 load_TLS_descriptor(t
, cpu
, 2);
464 xen_mc_issue(PARAVIRT_LAZY_CPU
);
468 static void xen_load_gs_index(unsigned int idx
)
470 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL
, idx
))
475 static void xen_write_ldt_entry(struct desc_struct
*dt
, int entrynum
,
478 xmaddr_t mach_lp
= arbitrary_virt_to_machine(&dt
[entrynum
]);
479 u64 entry
= *(u64
*)ptr
;
484 if (HYPERVISOR_update_descriptor(mach_lp
.maddr
, entry
))
490 static int cvt_gate_to_trap(int vector
, const gate_desc
*val
,
491 struct trap_info
*info
)
495 if (val
->type
!= GATE_TRAP
&& val
->type
!= GATE_INTERRUPT
)
498 info
->vector
= vector
;
500 addr
= gate_offset(*val
);
503 * Look for known traps using IST, and substitute them
504 * appropriately. The debugger ones are the only ones we care
505 * about. Xen will handle faults like double_fault and
506 * machine_check, so we should never see them. Warn if
507 * there's an unexpected IST-using fault handler.
509 if (addr
== (unsigned long)debug
)
510 addr
= (unsigned long)xen_debug
;
511 else if (addr
== (unsigned long)int3
)
512 addr
= (unsigned long)xen_int3
;
513 else if (addr
== (unsigned long)stack_segment
)
514 addr
= (unsigned long)xen_stack_segment
;
515 else if (addr
== (unsigned long)double_fault
||
516 addr
== (unsigned long)nmi
) {
517 /* Don't need to handle these */
519 #ifdef CONFIG_X86_MCE
520 } else if (addr
== (unsigned long)machine_check
) {
524 /* Some other trap using IST? */
525 if (WARN_ON(val
->ist
!= 0))
528 #endif /* CONFIG_X86_64 */
529 info
->address
= addr
;
531 info
->cs
= gate_segment(*val
);
532 info
->flags
= val
->dpl
;
533 /* interrupt gates clear IF */
534 if (val
->type
== GATE_INTERRUPT
)
535 info
->flags
|= 1 << 2;
540 /* Locations of each CPU's IDT */
541 static DEFINE_PER_CPU(struct desc_ptr
, idt_desc
);
543 /* Set an IDT entry. If the entry is part of the current IDT, then
545 static void xen_write_idt_entry(gate_desc
*dt
, int entrynum
, const gate_desc
*g
)
547 unsigned long p
= (unsigned long)&dt
[entrynum
];
548 unsigned long start
, end
;
552 start
= __get_cpu_var(idt_desc
).address
;
553 end
= start
+ __get_cpu_var(idt_desc
).size
+ 1;
557 native_write_idt_entry(dt
, entrynum
, g
);
559 if (p
>= start
&& (p
+ 8) <= end
) {
560 struct trap_info info
[2];
564 if (cvt_gate_to_trap(entrynum
, g
, &info
[0]))
565 if (HYPERVISOR_set_trap_table(info
))
572 static void xen_convert_trap_info(const struct desc_ptr
*desc
,
573 struct trap_info
*traps
)
575 unsigned in
, out
, count
;
577 count
= (desc
->size
+1) / sizeof(gate_desc
);
580 for (in
= out
= 0; in
< count
; in
++) {
581 gate_desc
*entry
= (gate_desc
*)(desc
->address
) + in
;
583 if (cvt_gate_to_trap(in
, entry
, &traps
[out
]))
586 traps
[out
].address
= 0;
589 void xen_copy_trap_info(struct trap_info
*traps
)
591 const struct desc_ptr
*desc
= &__get_cpu_var(idt_desc
);
593 xen_convert_trap_info(desc
, traps
);
596 /* Load a new IDT into Xen. In principle this can be per-CPU, so we
597 hold a spinlock to protect the static traps[] array (static because
598 it avoids allocation, and saves stack space). */
599 static void xen_load_idt(const struct desc_ptr
*desc
)
601 static DEFINE_SPINLOCK(lock
);
602 static struct trap_info traps
[257];
606 __get_cpu_var(idt_desc
) = *desc
;
608 xen_convert_trap_info(desc
, traps
);
611 if (HYPERVISOR_set_trap_table(traps
))
617 /* Write a GDT descriptor entry. Ignore LDT descriptors, since
618 they're handled differently. */
619 static void xen_write_gdt_entry(struct desc_struct
*dt
, int entry
,
620 const void *desc
, int type
)
631 xmaddr_t maddr
= arbitrary_virt_to_machine(&dt
[entry
]);
634 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
644 * Version of write_gdt_entry for use at early boot-time needed to
645 * update an entry as simply as possible.
647 static __init
void xen_write_gdt_entry_boot(struct desc_struct
*dt
, int entry
,
648 const void *desc
, int type
)
657 xmaddr_t maddr
= virt_to_machine(&dt
[entry
]);
659 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
660 dt
[entry
] = *(struct desc_struct
*)desc
;
666 static void xen_load_sp0(struct tss_struct
*tss
,
667 struct thread_struct
*thread
)
669 struct multicall_space mcs
= xen_mc_entry(0);
670 MULTI_stack_switch(mcs
.mc
, __KERNEL_DS
, thread
->sp0
);
671 xen_mc_issue(PARAVIRT_LAZY_CPU
);
674 static void xen_set_iopl_mask(unsigned mask
)
676 struct physdev_set_iopl set_iopl
;
678 /* Force the change at ring 0. */
679 set_iopl
.iopl
= (mask
== 0) ? 1 : (mask
>> 12) & 3;
680 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
683 static void xen_io_delay(void)
687 #ifdef CONFIG_X86_LOCAL_APIC
688 static u32
xen_apic_read(u32 reg
)
693 static void xen_apic_write(u32 reg
, u32 val
)
695 /* Warn to see if there's any stray references */
699 static u64
xen_apic_icr_read(void)
704 static void xen_apic_icr_write(u32 low
, u32 id
)
706 /* Warn to see if there's any stray references */
710 static void xen_apic_wait_icr_idle(void)
715 static u32
xen_safe_apic_wait_icr_idle(void)
720 static void set_xen_basic_apic_ops(void)
722 apic
->read
= xen_apic_read
;
723 apic
->write
= xen_apic_write
;
724 apic
->icr_read
= xen_apic_icr_read
;
725 apic
->icr_write
= xen_apic_icr_write
;
726 apic
->wait_icr_idle
= xen_apic_wait_icr_idle
;
727 apic
->safe_wait_icr_idle
= xen_safe_apic_wait_icr_idle
;
733 static void xen_clts(void)
735 struct multicall_space mcs
;
737 mcs
= xen_mc_entry(0);
739 MULTI_fpu_taskswitch(mcs
.mc
, 0);
741 xen_mc_issue(PARAVIRT_LAZY_CPU
);
744 static DEFINE_PER_CPU(unsigned long, xen_cr0_value
);
746 static unsigned long xen_read_cr0(void)
748 unsigned long cr0
= percpu_read(xen_cr0_value
);
750 if (unlikely(cr0
== 0)) {
751 cr0
= native_read_cr0();
752 percpu_write(xen_cr0_value
, cr0
);
758 static void xen_write_cr0(unsigned long cr0
)
760 struct multicall_space mcs
;
762 percpu_write(xen_cr0_value
, cr0
);
764 /* Only pay attention to cr0.TS; everything else is
766 mcs
= xen_mc_entry(0);
768 MULTI_fpu_taskswitch(mcs
.mc
, (cr0
& X86_CR0_TS
) != 0);
770 xen_mc_issue(PARAVIRT_LAZY_CPU
);
773 static void xen_write_cr4(unsigned long cr4
)
778 native_write_cr4(cr4
);
781 static int xen_write_msr_safe(unsigned int msr
, unsigned low
, unsigned high
)
792 case MSR_FS_BASE
: which
= SEGBASE_FS
; goto set
;
793 case MSR_KERNEL_GS_BASE
: which
= SEGBASE_GS_USER
; goto set
;
794 case MSR_GS_BASE
: which
= SEGBASE_GS_KERNEL
; goto set
;
797 base
= ((u64
)high
<< 32) | low
;
798 if (HYPERVISOR_set_segment_base(which
, base
) != 0)
806 case MSR_SYSCALL_MASK
:
807 case MSR_IA32_SYSENTER_CS
:
808 case MSR_IA32_SYSENTER_ESP
:
809 case MSR_IA32_SYSENTER_EIP
:
810 /* Fast syscall setup is all done in hypercalls, so
811 these are all ignored. Stub them out here to stop
812 Xen console noise. */
816 ret
= native_write_msr_safe(msr
, low
, high
);
822 void xen_setup_shared_info(void)
824 if (!xen_feature(XENFEAT_auto_translated_physmap
)) {
825 set_fixmap(FIX_PARAVIRT_BOOTMAP
,
826 xen_start_info
->shared_info
);
828 HYPERVISOR_shared_info
=
829 (struct shared_info
*)fix_to_virt(FIX_PARAVIRT_BOOTMAP
);
831 HYPERVISOR_shared_info
=
832 (struct shared_info
*)__va(xen_start_info
->shared_info
);
835 /* In UP this is as good a place as any to set up shared info */
836 xen_setup_vcpu_info_placement();
839 xen_setup_mfn_list_list();
842 /* This is called once we have the cpu_possible_map */
843 void xen_setup_vcpu_info_placement(void)
847 for_each_possible_cpu(cpu
)
850 /* xen_vcpu_setup managed to place the vcpu_info within the
851 percpu area for all cpus, so make use of it */
852 if (have_vcpu_info_placement
) {
853 printk(KERN_INFO
"Xen: using vcpu_info placement\n");
855 pv_irq_ops
.save_fl
= __PV_IS_CALLEE_SAVE(xen_save_fl_direct
);
856 pv_irq_ops
.restore_fl
= __PV_IS_CALLEE_SAVE(xen_restore_fl_direct
);
857 pv_irq_ops
.irq_disable
= __PV_IS_CALLEE_SAVE(xen_irq_disable_direct
);
858 pv_irq_ops
.irq_enable
= __PV_IS_CALLEE_SAVE(xen_irq_enable_direct
);
859 pv_mmu_ops
.read_cr2
= xen_read_cr2_direct
;
863 static unsigned xen_patch(u8 type
, u16 clobbers
, void *insnbuf
,
864 unsigned long addr
, unsigned len
)
866 char *start
, *end
, *reloc
;
869 start
= end
= reloc
= NULL
;
871 #define SITE(op, x) \
872 case PARAVIRT_PATCH(op.x): \
873 if (have_vcpu_info_placement) { \
874 start = (char *)xen_##x##_direct; \
875 end = xen_##x##_direct_end; \
876 reloc = xen_##x##_direct_reloc; \
881 SITE(pv_irq_ops
, irq_enable
);
882 SITE(pv_irq_ops
, irq_disable
);
883 SITE(pv_irq_ops
, save_fl
);
884 SITE(pv_irq_ops
, restore_fl
);
888 if (start
== NULL
|| (end
-start
) > len
)
891 ret
= paravirt_patch_insns(insnbuf
, len
, start
, end
);
893 /* Note: because reloc is assigned from something that
894 appears to be an array, gcc assumes it's non-null,
895 but doesn't know its relationship with start and
897 if (reloc
> start
&& reloc
< end
) {
898 int reloc_off
= reloc
- start
;
899 long *relocp
= (long *)(insnbuf
+ reloc_off
);
900 long delta
= start
- (char *)addr
;
908 ret
= paravirt_patch_default(type
, clobbers
, insnbuf
,
916 static const struct pv_info xen_info __initdata
= {
917 .paravirt_enabled
= 1,
918 .shared_kernel_pmd
= 0,
923 static const struct pv_init_ops xen_init_ops __initdata
= {
927 static const struct pv_time_ops xen_time_ops __initdata
= {
928 .sched_clock
= xen_sched_clock
,
931 static const struct pv_cpu_ops xen_cpu_ops __initdata
= {
934 .set_debugreg
= xen_set_debugreg
,
935 .get_debugreg
= xen_get_debugreg
,
939 .read_cr0
= xen_read_cr0
,
940 .write_cr0
= xen_write_cr0
,
942 .read_cr4
= native_read_cr4
,
943 .read_cr4_safe
= native_read_cr4_safe
,
944 .write_cr4
= xen_write_cr4
,
946 .wbinvd
= native_wbinvd
,
948 .read_msr
= native_read_msr_safe
,
949 .write_msr
= xen_write_msr_safe
,
950 .read_tsc
= native_read_tsc
,
951 .read_pmc
= native_read_pmc
,
954 .irq_enable_sysexit
= xen_sysexit
,
956 .usergs_sysret32
= xen_sysret32
,
957 .usergs_sysret64
= xen_sysret64
,
960 .load_tr_desc
= paravirt_nop
,
961 .set_ldt
= xen_set_ldt
,
962 .load_gdt
= xen_load_gdt
,
963 .load_idt
= xen_load_idt
,
964 .load_tls
= xen_load_tls
,
966 .load_gs_index
= xen_load_gs_index
,
969 .alloc_ldt
= xen_alloc_ldt
,
970 .free_ldt
= xen_free_ldt
,
972 .store_gdt
= native_store_gdt
,
973 .store_idt
= native_store_idt
,
974 .store_tr
= xen_store_tr
,
976 .write_ldt_entry
= xen_write_ldt_entry
,
977 .write_gdt_entry
= xen_write_gdt_entry
,
978 .write_idt_entry
= xen_write_idt_entry
,
979 .load_sp0
= xen_load_sp0
,
981 .set_iopl_mask
= xen_set_iopl_mask
,
982 .io_delay
= xen_io_delay
,
984 /* Xen takes care of %gs when switching to usermode for us */
985 .swapgs
= paravirt_nop
,
987 .start_context_switch
= paravirt_start_context_switch
,
988 .end_context_switch
= xen_end_context_switch
,
991 static const struct pv_apic_ops xen_apic_ops __initdata
= {
992 #ifdef CONFIG_X86_LOCAL_APIC
993 .startup_ipi_hook
= paravirt_nop
,
997 static void xen_reboot(int reason
)
999 struct sched_shutdown r
= { .reason
= reason
};
1005 if (HYPERVISOR_sched_op(SCHEDOP_shutdown
, &r
))
1009 static void xen_restart(char *msg
)
1011 xen_reboot(SHUTDOWN_reboot
);
1014 static void xen_emergency_restart(void)
1016 xen_reboot(SHUTDOWN_reboot
);
1019 static void xen_machine_halt(void)
1021 xen_reboot(SHUTDOWN_poweroff
);
1024 static void xen_crash_shutdown(struct pt_regs
*regs
)
1026 xen_reboot(SHUTDOWN_crash
);
1029 static const struct machine_ops __initdata xen_machine_ops
= {
1030 .restart
= xen_restart
,
1031 .halt
= xen_machine_halt
,
1032 .power_off
= xen_machine_halt
,
1033 .shutdown
= xen_machine_halt
,
1034 .crash_shutdown
= xen_crash_shutdown
,
1035 .emergency_restart
= xen_emergency_restart
,
1039 * Set up the GDT and segment registers for -fstack-protector. Until
1040 * we do this, we have to be careful not to call any stack-protected
1041 * function, which is most of the kernel.
1043 static void __init
xen_setup_stackprotector(void)
1045 pv_cpu_ops
.write_gdt_entry
= xen_write_gdt_entry_boot
;
1046 pv_cpu_ops
.load_gdt
= xen_load_gdt_boot
;
1048 setup_stack_canary_segment(0);
1049 switch_to_new_gdt(0);
1051 pv_cpu_ops
.write_gdt_entry
= xen_write_gdt_entry
;
1052 pv_cpu_ops
.load_gdt
= xen_load_gdt
;
1055 /* First C function to be called on Xen boot */
1056 asmlinkage
void __init
xen_start_kernel(void)
1060 if (!xen_start_info
)
1063 xen_domain_type
= XEN_PV_DOMAIN
;
1065 /* Install Xen paravirt ops */
1067 pv_init_ops
= xen_init_ops
;
1068 pv_time_ops
= xen_time_ops
;
1069 pv_cpu_ops
= xen_cpu_ops
;
1070 pv_apic_ops
= xen_apic_ops
;
1072 x86_init
.resources
.memory_setup
= xen_memory_setup
;
1073 x86_init
.oem
.arch_setup
= xen_arch_setup
;
1074 x86_init
.oem
.banner
= xen_banner
;
1076 x86_init
.timers
.timer_init
= xen_time_init
;
1077 x86_init
.timers
.setup_percpu_clockev
= x86_init_noop
;
1078 x86_cpuinit
.setup_percpu_clockev
= x86_init_noop
;
1080 x86_platform
.calibrate_tsc
= xen_tsc_khz
;
1081 x86_platform
.get_wallclock
= xen_get_wallclock
;
1082 x86_platform
.set_wallclock
= xen_set_wallclock
;
1085 * Set up some pagetable state before starting to set any ptes.
1090 /* Prevent unwanted bits from being set in PTEs. */
1091 __supported_pte_mask
&= ~_PAGE_GLOBAL
;
1092 if (!xen_initial_domain())
1093 __supported_pte_mask
&= ~(_PAGE_PWT
| _PAGE_PCD
);
1095 __supported_pte_mask
|= _PAGE_IOMAP
;
1097 /* Work out if we support NX */
1100 xen_setup_features();
1103 if (!xen_feature(XENFEAT_auto_translated_physmap
))
1104 xen_build_dynamic_phys_to_machine();
1107 * Set up kernel GDT and segment registers, mainly so that
1108 * -fstack-protector code can be executed.
1110 xen_setup_stackprotector();
1113 xen_init_cpuid_mask();
1115 #ifdef CONFIG_X86_LOCAL_APIC
1117 * set up the basic apic ops.
1119 set_xen_basic_apic_ops();
1122 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad
)) {
1123 pv_mmu_ops
.ptep_modify_prot_start
= xen_ptep_modify_prot_start
;
1124 pv_mmu_ops
.ptep_modify_prot_commit
= xen_ptep_modify_prot_commit
;
1127 machine_ops
= xen_machine_ops
;
1130 * The only reliable way to retain the initial address of the
1131 * percpu gdt_page is to remember it here, so we can go and
1132 * mark it RW later, when the initial percpu area is freed.
1134 xen_initial_gdt
= &per_cpu(gdt_page
, 0);
1138 pgd
= (pgd_t
*)xen_start_info
->pt_base
;
1140 /* Don't do the full vcpu_info placement stuff until we have a
1141 possible map and a non-dummy shared_info. */
1142 per_cpu(xen_vcpu
, 0) = &HYPERVISOR_shared_info
->vcpu_info
[0];
1144 local_irq_disable();
1145 early_boot_irqs_off();
1147 xen_raw_console_write("mapping kernel into physical memory\n");
1148 pgd
= xen_setup_kernel_pagetable(pgd
, xen_start_info
->nr_pages
);
1152 /* keep using Xen gdt for now; no urgent need to change it */
1154 pv_info
.kernel_rpl
= 1;
1155 if (xen_feature(XENFEAT_supervisor_mode_kernel
))
1156 pv_info
.kernel_rpl
= 0;
1158 /* set the limit of our address space */
1161 #ifdef CONFIG_X86_32
1162 /* set up basic CPUID stuff */
1163 cpu_detect(&new_cpu_data
);
1164 new_cpu_data
.hard_math
= 1;
1165 new_cpu_data
.wp_works_ok
= 1;
1166 new_cpu_data
.x86_capability
[0] = cpuid_edx(1);
1169 /* Poke various useful things into boot_params */
1170 boot_params
.hdr
.type_of_loader
= (9 << 4) | 0;
1171 boot_params
.hdr
.ramdisk_image
= xen_start_info
->mod_start
1172 ? __pa(xen_start_info
->mod_start
) : 0;
1173 boot_params
.hdr
.ramdisk_size
= xen_start_info
->mod_len
;
1174 boot_params
.hdr
.cmd_line_ptr
= __pa(xen_start_info
->cmd_line
);
1176 if (!xen_initial_domain()) {
1177 add_preferred_console("xenboot", 0, NULL
);
1178 add_preferred_console("tty", 0, NULL
);
1179 add_preferred_console("hvc", 0, NULL
);
1181 /* Make sure ACS will be enabled */
1186 xen_raw_console_write("about to get started...\n");
1188 xen_setup_runstate_info(0);
1190 /* Start the world */
1191 #ifdef CONFIG_X86_32
1192 i386_start_kernel();
1194 x86_64_start_reservations((char *)__pa_symbol(&boot_params
));