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>
46 #include <asm/paravirt.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>
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>
68 #include "multicalls.h"
70 EXPORT_SYMBOL_GPL(hypercall_page
);
72 DEFINE_PER_CPU(struct vcpu_info
*, xen_vcpu
);
73 DEFINE_PER_CPU(struct vcpu_info
, xen_vcpu_info
);
75 enum xen_domain_type xen_domain_type
= XEN_NATIVE
;
76 EXPORT_SYMBOL_GPL(xen_domain_type
);
78 struct start_info
*xen_start_info
;
79 EXPORT_SYMBOL_GPL(xen_start_info
);
81 struct shared_info xen_dummy_shared_info
;
83 void *xen_initial_gdt
;
85 RESERVE_BRK(shared_info_page_brk
, PAGE_SIZE
);
86 __read_mostly
int xen_have_vector_callback
;
87 EXPORT_SYMBOL_GPL(xen_have_vector_callback
);
90 * Point at some empty memory to start with. We map the real shared_info
91 * page as soon as fixmap is up and running.
93 struct shared_info
*HYPERVISOR_shared_info
= (void *)&xen_dummy_shared_info
;
96 * Flag to determine whether vcpu info placement is available on all
97 * VCPUs. We assume it is to start with, and then set it to zero on
98 * the first failure. This is because it can succeed on some VCPUs
99 * and not others, since it can involve hypervisor memory allocation,
100 * or because the guest failed to guarantee all the appropriate
101 * constraints on all VCPUs (ie buffer can't cross a page boundary).
103 * Note that any particular CPU may be using a placed vcpu structure,
104 * but we can only optimise if the all are.
106 * 0: not available, 1: available
108 static int have_vcpu_info_placement
= 1;
110 static void clamp_max_cpus(void)
113 if (setup_max_cpus
> MAX_VIRT_CPUS
)
114 setup_max_cpus
= MAX_VIRT_CPUS
;
118 static void xen_vcpu_setup(int cpu
)
120 struct vcpu_register_vcpu_info info
;
122 struct vcpu_info
*vcpup
;
124 BUG_ON(HYPERVISOR_shared_info
== &xen_dummy_shared_info
);
126 if (cpu
< MAX_VIRT_CPUS
)
127 per_cpu(xen_vcpu
,cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
129 if (!have_vcpu_info_placement
) {
130 if (cpu
>= MAX_VIRT_CPUS
)
135 vcpup
= &per_cpu(xen_vcpu_info
, cpu
);
136 info
.mfn
= arbitrary_virt_to_mfn(vcpup
);
137 info
.offset
= offset_in_page(vcpup
);
139 /* Check to see if the hypervisor will put the vcpu_info
140 structure where we want it, which allows direct access via
141 a percpu-variable. */
142 err
= HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info
, cpu
, &info
);
145 printk(KERN_DEBUG
"register_vcpu_info failed: err=%d\n", err
);
146 have_vcpu_info_placement
= 0;
149 /* This cpu is using the registered vcpu info, even if
150 later ones fail to. */
151 per_cpu(xen_vcpu
, cpu
) = vcpup
;
156 * On restore, set the vcpu placement up again.
157 * If it fails, then we're in a bad state, since
158 * we can't back out from using it...
160 void xen_vcpu_restore(void)
164 for_each_online_cpu(cpu
) {
165 bool other_cpu
= (cpu
!= smp_processor_id());
168 HYPERVISOR_vcpu_op(VCPUOP_down
, cpu
, NULL
))
171 xen_setup_runstate_info(cpu
);
173 if (have_vcpu_info_placement
)
177 HYPERVISOR_vcpu_op(VCPUOP_up
, cpu
, NULL
))
182 static void __init
xen_banner(void)
184 unsigned version
= HYPERVISOR_xen_version(XENVER_version
, NULL
);
185 struct xen_extraversion extra
;
186 HYPERVISOR_xen_version(XENVER_extraversion
, &extra
);
188 printk(KERN_INFO
"Booting paravirtualized kernel on %s\n",
190 printk(KERN_INFO
"Xen version: %d.%d%s%s\n",
191 version
>> 16, version
& 0xffff, extra
.extraversion
,
192 xen_feature(XENFEAT_mmu_pt_update_preserve_ad
) ? " (preserve-AD)" : "");
195 static __read_mostly
unsigned int cpuid_leaf1_edx_mask
= ~0;
196 static __read_mostly
unsigned int cpuid_leaf1_ecx_mask
= ~0;
198 static void xen_cpuid(unsigned int *ax
, unsigned int *bx
,
199 unsigned int *cx
, unsigned int *dx
)
201 unsigned maskebx
= ~0;
202 unsigned maskecx
= ~0;
203 unsigned maskedx
= ~0;
206 * Mask out inconvenient features, to try and disable as many
207 * unsupported kernel subsystems as possible.
211 maskecx
= cpuid_leaf1_ecx_mask
;
212 maskedx
= cpuid_leaf1_edx_mask
;
216 /* Suppress extended topology stuff */
221 asm(XEN_EMULATE_PREFIX
"cpuid"
226 : "0" (*ax
), "2" (*cx
));
233 static __init
void xen_init_cpuid_mask(void)
235 unsigned int ax
, bx
, cx
, dx
;
237 cpuid_leaf1_edx_mask
=
238 ~((1 << X86_FEATURE_MCE
) | /* disable MCE */
239 (1 << X86_FEATURE_MCA
) | /* disable MCA */
240 (1 << X86_FEATURE_MTRR
) | /* disable MTRR */
241 (1 << X86_FEATURE_ACC
)); /* thermal monitoring */
243 if (!xen_initial_domain())
244 cpuid_leaf1_edx_mask
&=
245 ~((1 << X86_FEATURE_APIC
) | /* disable local APIC */
246 (1 << X86_FEATURE_ACPI
)); /* disable ACPI */
250 xen_cpuid(&ax
, &bx
, &cx
, &dx
);
252 /* cpuid claims we support xsave; try enabling it to see what happens */
253 if (cx
& (1 << (X86_FEATURE_XSAVE
% 32))) {
256 set_in_cr4(X86_CR4_OSXSAVE
);
260 if ((cr4
& X86_CR4_OSXSAVE
) == 0)
261 cpuid_leaf1_ecx_mask
&= ~(1 << (X86_FEATURE_XSAVE
% 32));
263 clear_in_cr4(X86_CR4_OSXSAVE
);
267 static void xen_set_debugreg(int reg
, unsigned long val
)
269 HYPERVISOR_set_debugreg(reg
, val
);
272 static unsigned long xen_get_debugreg(int reg
)
274 return HYPERVISOR_get_debugreg(reg
);
277 static void xen_end_context_switch(struct task_struct
*next
)
280 paravirt_end_context_switch(next
);
283 static unsigned long xen_store_tr(void)
289 * Set the page permissions for a particular virtual address. If the
290 * address is a vmalloc mapping (or other non-linear mapping), then
291 * find the linear mapping of the page and also set its protections to
294 static void set_aliased_prot(void *v
, pgprot_t prot
)
302 ptep
= lookup_address((unsigned long)v
, &level
);
303 BUG_ON(ptep
== NULL
);
305 pfn
= pte_pfn(*ptep
);
306 page
= pfn_to_page(pfn
);
308 pte
= pfn_pte(pfn
, prot
);
310 if (HYPERVISOR_update_va_mapping((unsigned long)v
, pte
, 0))
313 if (!PageHighMem(page
)) {
314 void *av
= __va(PFN_PHYS(pfn
));
317 if (HYPERVISOR_update_va_mapping((unsigned long)av
, pte
, 0))
323 static void xen_alloc_ldt(struct desc_struct
*ldt
, unsigned entries
)
325 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
328 for(i
= 0; i
< entries
; i
+= entries_per_page
)
329 set_aliased_prot(ldt
+ i
, PAGE_KERNEL_RO
);
332 static void xen_free_ldt(struct desc_struct
*ldt
, unsigned entries
)
334 const unsigned entries_per_page
= PAGE_SIZE
/ LDT_ENTRY_SIZE
;
337 for(i
= 0; i
< entries
; i
+= entries_per_page
)
338 set_aliased_prot(ldt
+ i
, PAGE_KERNEL
);
341 static void xen_set_ldt(const void *addr
, unsigned entries
)
343 struct mmuext_op
*op
;
344 struct multicall_space mcs
= xen_mc_entry(sizeof(*op
));
347 op
->cmd
= MMUEXT_SET_LDT
;
348 op
->arg1
.linear_addr
= (unsigned long)addr
;
349 op
->arg2
.nr_ents
= entries
;
351 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
353 xen_mc_issue(PARAVIRT_LAZY_CPU
);
356 static void xen_load_gdt(const struct desc_ptr
*dtr
)
358 unsigned long va
= dtr
->address
;
359 unsigned int size
= dtr
->size
+ 1;
360 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
361 unsigned long frames
[pages
];
365 * A GDT can be up to 64k in size, which corresponds to 8192
366 * 8-byte entries, or 16 4k pages..
369 BUG_ON(size
> 65536);
370 BUG_ON(va
& ~PAGE_MASK
);
372 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
375 unsigned long pfn
, mfn
;
379 * The GDT is per-cpu and is in the percpu data area.
380 * That can be virtually mapped, so we need to do a
381 * page-walk to get the underlying MFN for the
382 * hypercall. The page can also be in the kernel's
383 * linear range, so we need to RO that mapping too.
385 ptep
= lookup_address(va
, &level
);
386 BUG_ON(ptep
== NULL
);
388 pfn
= pte_pfn(*ptep
);
389 mfn
= pfn_to_mfn(pfn
);
390 virt
= __va(PFN_PHYS(pfn
));
394 make_lowmem_page_readonly((void *)va
);
395 make_lowmem_page_readonly(virt
);
398 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
403 * load_gdt for early boot, when the gdt is only mapped once
405 static __init
void xen_load_gdt_boot(const struct desc_ptr
*dtr
)
407 unsigned long va
= dtr
->address
;
408 unsigned int size
= dtr
->size
+ 1;
409 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
410 unsigned long frames
[pages
];
414 * A GDT can be up to 64k in size, which corresponds to 8192
415 * 8-byte entries, or 16 4k pages..
418 BUG_ON(size
> 65536);
419 BUG_ON(va
& ~PAGE_MASK
);
421 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
423 unsigned long pfn
, mfn
;
425 pfn
= virt_to_pfn(va
);
426 mfn
= pfn_to_mfn(pfn
);
428 pte
= pfn_pte(pfn
, PAGE_KERNEL_RO
);
430 if (HYPERVISOR_update_va_mapping((unsigned long)va
, pte
, 0))
436 if (HYPERVISOR_set_gdt(frames
, size
/ sizeof(struct desc_struct
)))
440 static void load_TLS_descriptor(struct thread_struct
*t
,
441 unsigned int cpu
, unsigned int i
)
443 struct desc_struct
*gdt
= get_cpu_gdt_table(cpu
);
444 xmaddr_t maddr
= arbitrary_virt_to_machine(&gdt
[GDT_ENTRY_TLS_MIN
+i
]);
445 struct multicall_space mc
= __xen_mc_entry(0);
447 MULTI_update_descriptor(mc
.mc
, maddr
.maddr
, t
->tls_array
[i
]);
450 static void xen_load_tls(struct thread_struct
*t
, unsigned int cpu
)
453 * XXX sleazy hack: If we're being called in a lazy-cpu zone
454 * and lazy gs handling is enabled, it means we're in a
455 * context switch, and %gs has just been saved. This means we
456 * can zero it out to prevent faults on exit from the
457 * hypervisor if the next process has no %gs. Either way, it
458 * has been saved, and the new value will get loaded properly.
459 * This will go away as soon as Xen has been modified to not
460 * save/restore %gs for normal hypercalls.
462 * On x86_64, this hack is not used for %gs, because gs points
463 * to KERNEL_GS_BASE (and uses it for PDA references), so we
464 * must not zero %gs on x86_64
466 * For x86_64, we need to zero %fs, otherwise we may get an
467 * exception between the new %fs descriptor being loaded and
468 * %fs being effectively cleared at __switch_to().
470 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU
) {
480 load_TLS_descriptor(t
, cpu
, 0);
481 load_TLS_descriptor(t
, cpu
, 1);
482 load_TLS_descriptor(t
, cpu
, 2);
484 xen_mc_issue(PARAVIRT_LAZY_CPU
);
488 static void xen_load_gs_index(unsigned int idx
)
490 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL
, idx
))
495 static void xen_write_ldt_entry(struct desc_struct
*dt
, int entrynum
,
498 xmaddr_t mach_lp
= arbitrary_virt_to_machine(&dt
[entrynum
]);
499 u64 entry
= *(u64
*)ptr
;
504 if (HYPERVISOR_update_descriptor(mach_lp
.maddr
, entry
))
510 static int cvt_gate_to_trap(int vector
, const gate_desc
*val
,
511 struct trap_info
*info
)
515 if (val
->type
!= GATE_TRAP
&& val
->type
!= GATE_INTERRUPT
)
518 info
->vector
= vector
;
520 addr
= gate_offset(*val
);
523 * Look for known traps using IST, and substitute them
524 * appropriately. The debugger ones are the only ones we care
525 * about. Xen will handle faults like double_fault and
526 * machine_check, so we should never see them. Warn if
527 * there's an unexpected IST-using fault handler.
529 if (addr
== (unsigned long)debug
)
530 addr
= (unsigned long)xen_debug
;
531 else if (addr
== (unsigned long)int3
)
532 addr
= (unsigned long)xen_int3
;
533 else if (addr
== (unsigned long)stack_segment
)
534 addr
= (unsigned long)xen_stack_segment
;
535 else if (addr
== (unsigned long)double_fault
||
536 addr
== (unsigned long)nmi
) {
537 /* Don't need to handle these */
539 #ifdef CONFIG_X86_MCE
540 } else if (addr
== (unsigned long)machine_check
) {
544 /* Some other trap using IST? */
545 if (WARN_ON(val
->ist
!= 0))
548 #endif /* CONFIG_X86_64 */
549 info
->address
= addr
;
551 info
->cs
= gate_segment(*val
);
552 info
->flags
= val
->dpl
;
553 /* interrupt gates clear IF */
554 if (val
->type
== GATE_INTERRUPT
)
555 info
->flags
|= 1 << 2;
560 /* Locations of each CPU's IDT */
561 static DEFINE_PER_CPU(struct desc_ptr
, idt_desc
);
563 /* Set an IDT entry. If the entry is part of the current IDT, then
565 static void xen_write_idt_entry(gate_desc
*dt
, int entrynum
, const gate_desc
*g
)
567 unsigned long p
= (unsigned long)&dt
[entrynum
];
568 unsigned long start
, end
;
572 start
= __get_cpu_var(idt_desc
).address
;
573 end
= start
+ __get_cpu_var(idt_desc
).size
+ 1;
577 native_write_idt_entry(dt
, entrynum
, g
);
579 if (p
>= start
&& (p
+ 8) <= end
) {
580 struct trap_info info
[2];
584 if (cvt_gate_to_trap(entrynum
, g
, &info
[0]))
585 if (HYPERVISOR_set_trap_table(info
))
592 static void xen_convert_trap_info(const struct desc_ptr
*desc
,
593 struct trap_info
*traps
)
595 unsigned in
, out
, count
;
597 count
= (desc
->size
+1) / sizeof(gate_desc
);
600 for (in
= out
= 0; in
< count
; in
++) {
601 gate_desc
*entry
= (gate_desc
*)(desc
->address
) + in
;
603 if (cvt_gate_to_trap(in
, entry
, &traps
[out
]))
606 traps
[out
].address
= 0;
609 void xen_copy_trap_info(struct trap_info
*traps
)
611 const struct desc_ptr
*desc
= &__get_cpu_var(idt_desc
);
613 xen_convert_trap_info(desc
, traps
);
616 /* Load a new IDT into Xen. In principle this can be per-CPU, so we
617 hold a spinlock to protect the static traps[] array (static because
618 it avoids allocation, and saves stack space). */
619 static void xen_load_idt(const struct desc_ptr
*desc
)
621 static DEFINE_SPINLOCK(lock
);
622 static struct trap_info traps
[257];
626 __get_cpu_var(idt_desc
) = *desc
;
628 xen_convert_trap_info(desc
, traps
);
631 if (HYPERVISOR_set_trap_table(traps
))
637 /* Write a GDT descriptor entry. Ignore LDT descriptors, since
638 they're handled differently. */
639 static void xen_write_gdt_entry(struct desc_struct
*dt
, int entry
,
640 const void *desc
, int type
)
651 xmaddr_t maddr
= arbitrary_virt_to_machine(&dt
[entry
]);
654 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
664 * Version of write_gdt_entry for use at early boot-time needed to
665 * update an entry as simply as possible.
667 static __init
void xen_write_gdt_entry_boot(struct desc_struct
*dt
, int entry
,
668 const void *desc
, int type
)
677 xmaddr_t maddr
= virt_to_machine(&dt
[entry
]);
679 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
680 dt
[entry
] = *(struct desc_struct
*)desc
;
686 static void xen_load_sp0(struct tss_struct
*tss
,
687 struct thread_struct
*thread
)
689 struct multicall_space mcs
= xen_mc_entry(0);
690 MULTI_stack_switch(mcs
.mc
, __KERNEL_DS
, thread
->sp0
);
691 xen_mc_issue(PARAVIRT_LAZY_CPU
);
694 static void xen_set_iopl_mask(unsigned mask
)
696 struct physdev_set_iopl set_iopl
;
698 /* Force the change at ring 0. */
699 set_iopl
.iopl
= (mask
== 0) ? 1 : (mask
>> 12) & 3;
700 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
703 static void xen_io_delay(void)
707 #ifdef CONFIG_X86_LOCAL_APIC
708 static u32
xen_apic_read(u32 reg
)
713 static void xen_apic_write(u32 reg
, u32 val
)
715 /* Warn to see if there's any stray references */
719 static u64
xen_apic_icr_read(void)
724 static void xen_apic_icr_write(u32 low
, u32 id
)
726 /* Warn to see if there's any stray references */
730 static void xen_apic_wait_icr_idle(void)
735 static u32
xen_safe_apic_wait_icr_idle(void)
740 static void set_xen_basic_apic_ops(void)
742 apic
->read
= xen_apic_read
;
743 apic
->write
= xen_apic_write
;
744 apic
->icr_read
= xen_apic_icr_read
;
745 apic
->icr_write
= xen_apic_icr_write
;
746 apic
->wait_icr_idle
= xen_apic_wait_icr_idle
;
747 apic
->safe_wait_icr_idle
= xen_safe_apic_wait_icr_idle
;
752 static void xen_clts(void)
754 struct multicall_space mcs
;
756 mcs
= xen_mc_entry(0);
758 MULTI_fpu_taskswitch(mcs
.mc
, 0);
760 xen_mc_issue(PARAVIRT_LAZY_CPU
);
763 static DEFINE_PER_CPU(unsigned long, xen_cr0_value
);
765 static unsigned long xen_read_cr0(void)
767 unsigned long cr0
= percpu_read(xen_cr0_value
);
769 if (unlikely(cr0
== 0)) {
770 cr0
= native_read_cr0();
771 percpu_write(xen_cr0_value
, cr0
);
777 static void xen_write_cr0(unsigned long cr0
)
779 struct multicall_space mcs
;
781 percpu_write(xen_cr0_value
, cr0
);
783 /* Only pay attention to cr0.TS; everything else is
785 mcs
= xen_mc_entry(0);
787 MULTI_fpu_taskswitch(mcs
.mc
, (cr0
& X86_CR0_TS
) != 0);
789 xen_mc_issue(PARAVIRT_LAZY_CPU
);
792 static void xen_write_cr4(unsigned long cr4
)
797 native_write_cr4(cr4
);
800 static int xen_write_msr_safe(unsigned int msr
, unsigned low
, unsigned high
)
811 case MSR_FS_BASE
: which
= SEGBASE_FS
; goto set
;
812 case MSR_KERNEL_GS_BASE
: which
= SEGBASE_GS_USER
; goto set
;
813 case MSR_GS_BASE
: which
= SEGBASE_GS_KERNEL
; goto set
;
816 base
= ((u64
)high
<< 32) | low
;
817 if (HYPERVISOR_set_segment_base(which
, base
) != 0)
825 case MSR_SYSCALL_MASK
:
826 case MSR_IA32_SYSENTER_CS
:
827 case MSR_IA32_SYSENTER_ESP
:
828 case MSR_IA32_SYSENTER_EIP
:
829 /* Fast syscall setup is all done in hypercalls, so
830 these are all ignored. Stub them out here to stop
831 Xen console noise. */
834 case MSR_IA32_CR_PAT
:
835 if (smp_processor_id() == 0)
836 xen_set_pat(((u64
)high
<< 32) | low
);
840 ret
= native_write_msr_safe(msr
, low
, high
);
846 void xen_setup_shared_info(void)
848 if (!xen_feature(XENFEAT_auto_translated_physmap
)) {
849 set_fixmap(FIX_PARAVIRT_BOOTMAP
,
850 xen_start_info
->shared_info
);
852 HYPERVISOR_shared_info
=
853 (struct shared_info
*)fix_to_virt(FIX_PARAVIRT_BOOTMAP
);
855 HYPERVISOR_shared_info
=
856 (struct shared_info
*)__va(xen_start_info
->shared_info
);
859 /* In UP this is as good a place as any to set up shared info */
860 xen_setup_vcpu_info_placement();
863 xen_setup_mfn_list_list();
866 /* This is called once we have the cpu_possible_map */
867 void xen_setup_vcpu_info_placement(void)
871 for_each_possible_cpu(cpu
)
874 /* xen_vcpu_setup managed to place the vcpu_info within the
875 percpu area for all cpus, so make use of it */
876 if (have_vcpu_info_placement
) {
877 pv_irq_ops
.save_fl
= __PV_IS_CALLEE_SAVE(xen_save_fl_direct
);
878 pv_irq_ops
.restore_fl
= __PV_IS_CALLEE_SAVE(xen_restore_fl_direct
);
879 pv_irq_ops
.irq_disable
= __PV_IS_CALLEE_SAVE(xen_irq_disable_direct
);
880 pv_irq_ops
.irq_enable
= __PV_IS_CALLEE_SAVE(xen_irq_enable_direct
);
881 pv_mmu_ops
.read_cr2
= xen_read_cr2_direct
;
885 static unsigned xen_patch(u8 type
, u16 clobbers
, void *insnbuf
,
886 unsigned long addr
, unsigned len
)
888 char *start
, *end
, *reloc
;
891 start
= end
= reloc
= NULL
;
893 #define SITE(op, x) \
894 case PARAVIRT_PATCH(op.x): \
895 if (have_vcpu_info_placement) { \
896 start = (char *)xen_##x##_direct; \
897 end = xen_##x##_direct_end; \
898 reloc = xen_##x##_direct_reloc; \
903 SITE(pv_irq_ops
, irq_enable
);
904 SITE(pv_irq_ops
, irq_disable
);
905 SITE(pv_irq_ops
, save_fl
);
906 SITE(pv_irq_ops
, restore_fl
);
910 if (start
== NULL
|| (end
-start
) > len
)
913 ret
= paravirt_patch_insns(insnbuf
, len
, start
, end
);
915 /* Note: because reloc is assigned from something that
916 appears to be an array, gcc assumes it's non-null,
917 but doesn't know its relationship with start and
919 if (reloc
> start
&& reloc
< end
) {
920 int reloc_off
= reloc
- start
;
921 long *relocp
= (long *)(insnbuf
+ reloc_off
);
922 long delta
= start
- (char *)addr
;
930 ret
= paravirt_patch_default(type
, clobbers
, insnbuf
,
938 static const struct pv_info xen_info __initdata
= {
939 .paravirt_enabled
= 1,
940 .shared_kernel_pmd
= 0,
945 static const struct pv_init_ops xen_init_ops __initdata
= {
949 static const struct pv_cpu_ops xen_cpu_ops __initdata
= {
952 .set_debugreg
= xen_set_debugreg
,
953 .get_debugreg
= xen_get_debugreg
,
957 .read_cr0
= xen_read_cr0
,
958 .write_cr0
= xen_write_cr0
,
960 .read_cr4
= native_read_cr4
,
961 .read_cr4_safe
= native_read_cr4_safe
,
962 .write_cr4
= xen_write_cr4
,
964 .wbinvd
= native_wbinvd
,
966 .read_msr
= native_read_msr_safe
,
967 .write_msr
= xen_write_msr_safe
,
968 .read_tsc
= native_read_tsc
,
969 .read_pmc
= native_read_pmc
,
972 .irq_enable_sysexit
= xen_sysexit
,
974 .usergs_sysret32
= xen_sysret32
,
975 .usergs_sysret64
= xen_sysret64
,
978 .load_tr_desc
= paravirt_nop
,
979 .set_ldt
= xen_set_ldt
,
980 .load_gdt
= xen_load_gdt
,
981 .load_idt
= xen_load_idt
,
982 .load_tls
= xen_load_tls
,
984 .load_gs_index
= xen_load_gs_index
,
987 .alloc_ldt
= xen_alloc_ldt
,
988 .free_ldt
= xen_free_ldt
,
990 .store_gdt
= native_store_gdt
,
991 .store_idt
= native_store_idt
,
992 .store_tr
= xen_store_tr
,
994 .write_ldt_entry
= xen_write_ldt_entry
,
995 .write_gdt_entry
= xen_write_gdt_entry
,
996 .write_idt_entry
= xen_write_idt_entry
,
997 .load_sp0
= xen_load_sp0
,
999 .set_iopl_mask
= xen_set_iopl_mask
,
1000 .io_delay
= xen_io_delay
,
1002 /* Xen takes care of %gs when switching to usermode for us */
1003 .swapgs
= paravirt_nop
,
1005 .start_context_switch
= paravirt_start_context_switch
,
1006 .end_context_switch
= xen_end_context_switch
,
1009 static const struct pv_apic_ops xen_apic_ops __initdata
= {
1010 #ifdef CONFIG_X86_LOCAL_APIC
1011 .startup_ipi_hook
= paravirt_nop
,
1015 static void xen_reboot(int reason
)
1017 struct sched_shutdown r
= { .reason
= reason
};
1023 if (HYPERVISOR_sched_op(SCHEDOP_shutdown
, &r
))
1027 static void xen_restart(char *msg
)
1029 xen_reboot(SHUTDOWN_reboot
);
1032 static void xen_emergency_restart(void)
1034 xen_reboot(SHUTDOWN_reboot
);
1037 static void xen_machine_halt(void)
1039 xen_reboot(SHUTDOWN_poweroff
);
1042 static void xen_crash_shutdown(struct pt_regs
*regs
)
1044 xen_reboot(SHUTDOWN_crash
);
1048 xen_panic_event(struct notifier_block
*this, unsigned long event
, void *ptr
)
1050 xen_reboot(SHUTDOWN_crash
);
1054 static struct notifier_block xen_panic_block
= {
1055 .notifier_call
= xen_panic_event
,
1058 int xen_panic_handler_init(void)
1060 atomic_notifier_chain_register(&panic_notifier_list
, &xen_panic_block
);
1064 static const struct machine_ops __initdata xen_machine_ops
= {
1065 .restart
= xen_restart
,
1066 .halt
= xen_machine_halt
,
1067 .power_off
= xen_machine_halt
,
1068 .shutdown
= xen_machine_halt
,
1069 .crash_shutdown
= xen_crash_shutdown
,
1070 .emergency_restart
= xen_emergency_restart
,
1074 * Set up the GDT and segment registers for -fstack-protector. Until
1075 * we do this, we have to be careful not to call any stack-protected
1076 * function, which is most of the kernel.
1078 static void __init
xen_setup_stackprotector(void)
1080 pv_cpu_ops
.write_gdt_entry
= xen_write_gdt_entry_boot
;
1081 pv_cpu_ops
.load_gdt
= xen_load_gdt_boot
;
1083 setup_stack_canary_segment(0);
1084 switch_to_new_gdt(0);
1086 pv_cpu_ops
.write_gdt_entry
= xen_write_gdt_entry
;
1087 pv_cpu_ops
.load_gdt
= xen_load_gdt
;
1090 /* First C function to be called on Xen boot */
1091 asmlinkage
void __init
xen_start_kernel(void)
1095 if (!xen_start_info
)
1098 xen_domain_type
= XEN_PV_DOMAIN
;
1100 /* Install Xen paravirt ops */
1102 pv_init_ops
= xen_init_ops
;
1103 pv_cpu_ops
= xen_cpu_ops
;
1104 pv_apic_ops
= xen_apic_ops
;
1106 x86_init
.resources
.memory_setup
= xen_memory_setup
;
1107 x86_init
.oem
.arch_setup
= xen_arch_setup
;
1108 x86_init
.oem
.banner
= xen_banner
;
1110 xen_init_time_ops();
1113 * Set up some pagetable state before starting to set any ptes.
1118 /* Prevent unwanted bits from being set in PTEs. */
1119 __supported_pte_mask
&= ~_PAGE_GLOBAL
;
1120 if (!xen_initial_domain())
1121 __supported_pte_mask
&= ~(_PAGE_PWT
| _PAGE_PCD
);
1123 __supported_pte_mask
|= _PAGE_IOMAP
;
1126 * Prevent page tables from being allocated in highmem, even
1127 * if CONFIG_HIGHPTE is enabled.
1129 __userpte_alloc_gfp
&= ~__GFP_HIGHMEM
;
1131 /* Work out if we support NX */
1134 xen_setup_features();
1137 if (!xen_feature(XENFEAT_auto_translated_physmap
))
1138 xen_build_dynamic_phys_to_machine();
1141 * Set up kernel GDT and segment registers, mainly so that
1142 * -fstack-protector code can be executed.
1144 xen_setup_stackprotector();
1147 xen_init_cpuid_mask();
1149 #ifdef CONFIG_X86_LOCAL_APIC
1151 * set up the basic apic ops.
1153 set_xen_basic_apic_ops();
1156 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad
)) {
1157 pv_mmu_ops
.ptep_modify_prot_start
= xen_ptep_modify_prot_start
;
1158 pv_mmu_ops
.ptep_modify_prot_commit
= xen_ptep_modify_prot_commit
;
1161 machine_ops
= xen_machine_ops
;
1164 * The only reliable way to retain the initial address of the
1165 * percpu gdt_page is to remember it here, so we can go and
1166 * mark it RW later, when the initial percpu area is freed.
1168 xen_initial_gdt
= &per_cpu(gdt_page
, 0);
1172 pgd
= (pgd_t
*)xen_start_info
->pt_base
;
1174 if (!xen_initial_domain())
1175 __supported_pte_mask
&= ~(_PAGE_PWT
| _PAGE_PCD
);
1177 __supported_pte_mask
|= _PAGE_IOMAP
;
1178 /* Don't do the full vcpu_info placement stuff until we have a
1179 possible map and a non-dummy shared_info. */
1180 per_cpu(xen_vcpu
, 0) = &HYPERVISOR_shared_info
->vcpu_info
[0];
1182 local_irq_disable();
1183 early_boot_irqs_off();
1187 xen_raw_console_write("mapping kernel into physical memory\n");
1188 pgd
= xen_setup_kernel_pagetable(pgd
, xen_start_info
->nr_pages
);
1189 xen_ident_map_ISA();
1191 /* Allocate and initialize top and mid mfn levels for p2m structure */
1192 xen_build_mfn_list_list();
1196 /* keep using Xen gdt for now; no urgent need to change it */
1198 #ifdef CONFIG_X86_32
1199 pv_info
.kernel_rpl
= 1;
1200 if (xen_feature(XENFEAT_supervisor_mode_kernel
))
1201 pv_info
.kernel_rpl
= 0;
1203 pv_info
.kernel_rpl
= 0;
1206 /* set the limit of our address space */
1209 #ifdef CONFIG_X86_32
1210 /* set up basic CPUID stuff */
1211 cpu_detect(&new_cpu_data
);
1212 new_cpu_data
.hard_math
= 1;
1213 new_cpu_data
.wp_works_ok
= 1;
1214 new_cpu_data
.x86_capability
[0] = cpuid_edx(1);
1217 /* Poke various useful things into boot_params */
1218 boot_params
.hdr
.type_of_loader
= (9 << 4) | 0;
1219 boot_params
.hdr
.ramdisk_image
= xen_start_info
->mod_start
1220 ? __pa(xen_start_info
->mod_start
) : 0;
1221 boot_params
.hdr
.ramdisk_size
= xen_start_info
->mod_len
;
1222 boot_params
.hdr
.cmd_line_ptr
= __pa(xen_start_info
->cmd_line
);
1224 if (!xen_initial_domain()) {
1225 add_preferred_console("xenboot", 0, NULL
);
1226 add_preferred_console("tty", 0, NULL
);
1227 add_preferred_console("hvc", 0, NULL
);
1229 x86_init
.pci
.arch_init
= pci_xen_init
;
1231 /* Make sure ACS will be enabled */
1236 xen_raw_console_write("about to get started...\n");
1238 xen_setup_runstate_info(0);
1240 /* Start the world */
1241 #ifdef CONFIG_X86_32
1242 i386_start_kernel();
1244 x86_64_start_reservations((char *)__pa_symbol(&boot_params
));
1248 static uint32_t xen_cpuid_base(void)
1250 uint32_t base
, eax
, ebx
, ecx
, edx
;
1253 for (base
= 0x40000000; base
< 0x40010000; base
+= 0x100) {
1254 cpuid(base
, &eax
, &ebx
, &ecx
, &edx
);
1255 *(uint32_t *)(signature
+ 0) = ebx
;
1256 *(uint32_t *)(signature
+ 4) = ecx
;
1257 *(uint32_t *)(signature
+ 8) = edx
;
1260 if (!strcmp("XenVMMXenVMM", signature
) && ((eax
- base
) >= 2))
1267 static int init_hvm_pv_info(int *major
, int *minor
)
1269 uint32_t eax
, ebx
, ecx
, edx
, pages
, msr
, base
;
1272 base
= xen_cpuid_base();
1273 cpuid(base
+ 1, &eax
, &ebx
, &ecx
, &edx
);
1276 *minor
= eax
& 0xffff;
1277 printk(KERN_INFO
"Xen version %d.%d.\n", *major
, *minor
);
1279 cpuid(base
+ 2, &pages
, &msr
, &ecx
, &edx
);
1281 pfn
= __pa(hypercall_page
);
1282 wrmsr_safe(msr
, (u32
)pfn
, (u32
)(pfn
>> 32));
1284 xen_setup_features();
1287 pv_info
.kernel_rpl
= 0;
1289 xen_domain_type
= XEN_HVM_DOMAIN
;
1294 void xen_hvm_init_shared_info(void)
1297 struct xen_add_to_physmap xatp
;
1298 static struct shared_info
*shared_info_page
= 0;
1300 if (!shared_info_page
)
1301 shared_info_page
= (struct shared_info
*)
1302 extend_brk(PAGE_SIZE
, PAGE_SIZE
);
1303 xatp
.domid
= DOMID_SELF
;
1305 xatp
.space
= XENMAPSPACE_shared_info
;
1306 xatp
.gpfn
= __pa(shared_info_page
) >> PAGE_SHIFT
;
1307 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap
, &xatp
))
1310 HYPERVISOR_shared_info
= (struct shared_info
*)shared_info_page
;
1312 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
1313 * page, we use it in the event channel upcall and in some pvclock
1314 * related functions. We don't need the vcpu_info placement
1315 * optimizations because we don't use any pv_mmu or pv_irq op on
1317 * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
1318 * online but xen_hvm_init_shared_info is run at resume time too and
1319 * in that case multiple vcpus might be online. */
1320 for_each_online_cpu(cpu
) {
1321 per_cpu(xen_vcpu
, cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
1325 #ifdef CONFIG_XEN_PVHVM
1326 static int __cpuinit
xen_hvm_cpu_notify(struct notifier_block
*self
,
1327 unsigned long action
, void *hcpu
)
1329 int cpu
= (long)hcpu
;
1331 case CPU_UP_PREPARE
:
1332 per_cpu(xen_vcpu
, cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
1340 static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier
= {
1341 .notifier_call
= xen_hvm_cpu_notify
,
1344 static void __init
xen_hvm_guest_init(void)
1349 r
= init_hvm_pv_info(&major
, &minor
);
1353 xen_hvm_init_shared_info();
1355 if (xen_feature(XENFEAT_hvm_callback_vector
))
1356 xen_have_vector_callback
= 1;
1357 register_cpu_notifier(&xen_hvm_cpu_notifier
);
1358 xen_unplug_emulated_devices();
1359 have_vcpu_info_placement
= 0;
1360 x86_init
.irqs
.intr_init
= xen_init_IRQ
;
1361 xen_hvm_init_time_ops();
1362 xen_hvm_init_mmu_ops();
1365 static bool __init
xen_hvm_platform(void)
1367 if (xen_pv_domain())
1370 if (!xen_cpuid_base())
1376 const __refconst
struct hypervisor_x86 x86_hyper_xen_hvm
= {
1378 .detect
= xen_hvm_platform
,
1379 .init_platform
= xen_hvm_guest_init
,
1381 EXPORT_SYMBOL(x86_hyper_xen_hvm
);