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/physdev.h>
32 #include <xen/interface/vcpu.h>
33 #include <xen/interface/sched.h>
34 #include <xen/features.h>
36 #include <xen/hvc-console.h>
38 #include <asm/paravirt.h>
40 #include <asm/xen/hypercall.h>
41 #include <asm/xen/hypervisor.h>
42 #include <asm/fixmap.h>
43 #include <asm/processor.h>
44 #include <asm/msr-index.h>
45 #include <asm/setup.h>
47 #include <asm/pgtable.h>
48 #include <asm/tlbflush.h>
49 #include <asm/reboot.h>
53 #include "multicalls.h"
55 EXPORT_SYMBOL_GPL(hypercall_page
);
57 DEFINE_PER_CPU(struct vcpu_info
*, xen_vcpu
);
58 DEFINE_PER_CPU(struct vcpu_info
, xen_vcpu_info
);
61 * Identity map, in addition to plain kernel map. This needs to be
62 * large enough to allocate page table pages to allocate the rest.
63 * Each page can map 2MB.
65 static pte_t level1_ident_pgt
[PTRS_PER_PTE
* 4] __page_aligned_bss
;
68 /* l3 pud for userspace vsyscall mapping */
69 static pud_t level3_user_vsyscall
[PTRS_PER_PUD
] __page_aligned_bss
;
70 #endif /* CONFIG_X86_64 */
73 * Note about cr3 (pagetable base) values:
75 * xen_cr3 contains the current logical cr3 value; it contains the
76 * last set cr3. This may not be the current effective cr3, because
77 * its update may be being lazily deferred. However, a vcpu looking
78 * at its own cr3 can use this value knowing that it everything will
81 * xen_current_cr3 contains the actual vcpu cr3; it is set once the
82 * hypercall to set the vcpu cr3 is complete (so it may be a little
83 * out of date, but it will never be set early). If one vcpu is
84 * looking at another vcpu's cr3 value, it should use this variable.
86 DEFINE_PER_CPU(unsigned long, xen_cr3
); /* cr3 stored as physaddr */
87 DEFINE_PER_CPU(unsigned long, xen_current_cr3
); /* actual vcpu cr3 */
89 struct start_info
*xen_start_info
;
90 EXPORT_SYMBOL_GPL(xen_start_info
);
92 struct shared_info xen_dummy_shared_info
;
95 * Point at some empty memory to start with. We map the real shared_info
96 * page as soon as fixmap is up and running.
98 struct shared_info
*HYPERVISOR_shared_info
= (void *)&xen_dummy_shared_info
;
101 * Flag to determine whether vcpu info placement is available on all
102 * VCPUs. We assume it is to start with, and then set it to zero on
103 * the first failure. This is because it can succeed on some VCPUs
104 * and not others, since it can involve hypervisor memory allocation,
105 * or because the guest failed to guarantee all the appropriate
106 * constraints on all VCPUs (ie buffer can't cross a page boundary).
108 * Note that any particular CPU may be using a placed vcpu structure,
109 * but we can only optimise if the all are.
111 * 0: not available, 1: available
113 static int have_vcpu_info_placement
= 1;
115 static void xen_vcpu_setup(int cpu
)
117 struct vcpu_register_vcpu_info info
;
119 struct vcpu_info
*vcpup
;
121 BUG_ON(HYPERVISOR_shared_info
== &xen_dummy_shared_info
);
122 per_cpu(xen_vcpu
, cpu
) = &HYPERVISOR_shared_info
->vcpu_info
[cpu
];
124 if (!have_vcpu_info_placement
)
125 return; /* already tested, not available */
127 vcpup
= &per_cpu(xen_vcpu_info
, cpu
);
129 info
.mfn
= virt_to_mfn(vcpup
);
130 info
.offset
= offset_in_page(vcpup
);
132 printk(KERN_DEBUG
"trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
133 cpu
, vcpup
, info
.mfn
, info
.offset
);
135 /* Check to see if the hypervisor will put the vcpu_info
136 structure where we want it, which allows direct access via
137 a percpu-variable. */
138 err
= HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info
, cpu
, &info
);
141 printk(KERN_DEBUG
"register_vcpu_info failed: err=%d\n", err
);
142 have_vcpu_info_placement
= 0;
144 /* This cpu is using the registered vcpu info, even if
145 later ones fail to. */
146 per_cpu(xen_vcpu
, cpu
) = vcpup
;
148 printk(KERN_DEBUG
"cpu %d using vcpu_info at %p\n",
154 * On restore, set the vcpu placement up again.
155 * If it fails, then we're in a bad state, since
156 * we can't back out from using it...
158 void xen_vcpu_restore(void)
160 if (have_vcpu_info_placement
) {
163 for_each_online_cpu(cpu
) {
164 bool other_cpu
= (cpu
!= smp_processor_id());
167 HYPERVISOR_vcpu_op(VCPUOP_down
, cpu
, NULL
))
173 HYPERVISOR_vcpu_op(VCPUOP_up
, cpu
, NULL
))
177 BUG_ON(!have_vcpu_info_placement
);
181 static void __init
xen_banner(void)
183 unsigned version
= HYPERVISOR_xen_version(XENVER_version
, NULL
);
184 struct xen_extraversion extra
;
185 HYPERVISOR_xen_version(XENVER_extraversion
, &extra
);
187 printk(KERN_INFO
"Booting paravirtualized kernel on %s\n",
189 printk(KERN_INFO
"Xen version: %d.%d%s%s\n",
190 version
>> 16, version
& 0xffff, extra
.extraversion
,
191 xen_feature(XENFEAT_mmu_pt_update_preserve_ad
) ? " (preserve-AD)" : "");
194 static void xen_cpuid(unsigned int *ax
, unsigned int *bx
,
195 unsigned int *cx
, unsigned int *dx
)
197 unsigned maskedx
= ~0;
200 * Mask out inconvenient features, to try and disable as many
201 * unsupported kernel subsystems as possible.
204 maskedx
= ~((1 << X86_FEATURE_APIC
) | /* disable APIC */
205 (1 << X86_FEATURE_ACPI
) | /* disable ACPI */
206 (1 << X86_FEATURE_MCE
) | /* disable MCE */
207 (1 << X86_FEATURE_MCA
) | /* disable MCA */
208 (1 << X86_FEATURE_ACC
)); /* thermal monitoring */
210 asm(XEN_EMULATE_PREFIX
"cpuid"
215 : "0" (*ax
), "2" (*cx
));
219 static void xen_set_debugreg(int reg
, unsigned long val
)
221 HYPERVISOR_set_debugreg(reg
, val
);
224 static unsigned long xen_get_debugreg(int reg
)
226 return HYPERVISOR_get_debugreg(reg
);
229 static unsigned long xen_save_fl(void)
231 struct vcpu_info
*vcpu
;
234 vcpu
= x86_read_percpu(xen_vcpu
);
236 /* flag has opposite sense of mask */
237 flags
= !vcpu
->evtchn_upcall_mask
;
239 /* convert to IF type flag
243 return (-flags
) & X86_EFLAGS_IF
;
246 static void xen_restore_fl(unsigned long flags
)
248 struct vcpu_info
*vcpu
;
250 /* convert from IF type flag */
251 flags
= !(flags
& X86_EFLAGS_IF
);
253 /* There's a one instruction preempt window here. We need to
254 make sure we're don't switch CPUs between getting the vcpu
255 pointer and updating the mask. */
257 vcpu
= x86_read_percpu(xen_vcpu
);
258 vcpu
->evtchn_upcall_mask
= flags
;
259 preempt_enable_no_resched();
261 /* Doesn't matter if we get preempted here, because any
262 pending event will get dealt with anyway. */
265 preempt_check_resched();
266 barrier(); /* unmask then check (avoid races) */
267 if (unlikely(vcpu
->evtchn_upcall_pending
))
268 force_evtchn_callback();
272 static void xen_irq_disable(void)
274 /* There's a one instruction preempt window here. We need to
275 make sure we're don't switch CPUs between getting the vcpu
276 pointer and updating the mask. */
278 x86_read_percpu(xen_vcpu
)->evtchn_upcall_mask
= 1;
279 preempt_enable_no_resched();
282 static void xen_irq_enable(void)
284 struct vcpu_info
*vcpu
;
286 /* We don't need to worry about being preempted here, since
287 either a) interrupts are disabled, so no preemption, or b)
288 the caller is confused and is trying to re-enable interrupts
289 on an indeterminate processor. */
291 vcpu
= x86_read_percpu(xen_vcpu
);
292 vcpu
->evtchn_upcall_mask
= 0;
294 /* Doesn't matter if we get preempted here, because any
295 pending event will get dealt with anyway. */
297 barrier(); /* unmask then check (avoid races) */
298 if (unlikely(vcpu
->evtchn_upcall_pending
))
299 force_evtchn_callback();
302 static void xen_safe_halt(void)
304 /* Blocking includes an implicit local_irq_enable(). */
305 if (HYPERVISOR_sched_op(SCHEDOP_block
, NULL
) != 0)
309 static void xen_halt(void)
312 HYPERVISOR_vcpu_op(VCPUOP_down
, smp_processor_id(), NULL
);
317 static void xen_leave_lazy(void)
319 paravirt_leave_lazy(paravirt_get_lazy_mode());
323 static unsigned long xen_store_tr(void)
328 static void xen_set_ldt(const void *addr
, unsigned entries
)
330 struct mmuext_op
*op
;
331 struct multicall_space mcs
= xen_mc_entry(sizeof(*op
));
334 op
->cmd
= MMUEXT_SET_LDT
;
335 op
->arg1
.linear_addr
= (unsigned long)addr
;
336 op
->arg2
.nr_ents
= entries
;
338 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
340 xen_mc_issue(PARAVIRT_LAZY_CPU
);
343 static void xen_load_gdt(const struct desc_ptr
*dtr
)
345 unsigned long *frames
;
346 unsigned long va
= dtr
->address
;
347 unsigned int size
= dtr
->size
+ 1;
348 unsigned pages
= (size
+ PAGE_SIZE
- 1) / PAGE_SIZE
;
350 struct multicall_space mcs
;
352 /* A GDT can be up to 64k in size, which corresponds to 8192
353 8-byte entries, or 16 4k pages.. */
355 BUG_ON(size
> 65536);
356 BUG_ON(va
& ~PAGE_MASK
);
358 mcs
= xen_mc_entry(sizeof(*frames
) * pages
);
361 for (f
= 0; va
< dtr
->address
+ size
; va
+= PAGE_SIZE
, f
++) {
362 frames
[f
] = virt_to_mfn(va
);
363 make_lowmem_page_readonly((void *)va
);
366 MULTI_set_gdt(mcs
.mc
, frames
, size
/ sizeof(struct desc_struct
));
368 xen_mc_issue(PARAVIRT_LAZY_CPU
);
371 static void load_TLS_descriptor(struct thread_struct
*t
,
372 unsigned int cpu
, unsigned int i
)
374 struct desc_struct
*gdt
= get_cpu_gdt_table(cpu
);
375 xmaddr_t maddr
= virt_to_machine(&gdt
[GDT_ENTRY_TLS_MIN
+i
]);
376 struct multicall_space mc
= __xen_mc_entry(0);
378 MULTI_update_descriptor(mc
.mc
, maddr
.maddr
, t
->tls_array
[i
]);
381 static void xen_load_tls(struct thread_struct
*t
, unsigned int cpu
)
384 * XXX sleazy hack: If we're being called in a lazy-cpu zone,
385 * it means we're in a context switch, and %gs has just been
386 * saved. This means we can zero it out to prevent faults on
387 * exit from the hypervisor if the next process has no %gs.
388 * Either way, it has been saved, and the new value will get
389 * loaded properly. This will go away as soon as Xen has been
390 * modified to not save/restore %gs for normal hypercalls.
392 * On x86_64, this hack is not used for %gs, because gs points
393 * to KERNEL_GS_BASE (and uses it for PDA references), so we
394 * must not zero %gs on x86_64
396 * For x86_64, we need to zero %fs, otherwise we may get an
397 * exception between the new %fs descriptor being loaded and
398 * %fs being effectively cleared at __switch_to().
400 if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU
) {
410 load_TLS_descriptor(t
, cpu
, 0);
411 load_TLS_descriptor(t
, cpu
, 1);
412 load_TLS_descriptor(t
, cpu
, 2);
414 xen_mc_issue(PARAVIRT_LAZY_CPU
);
418 static void xen_load_gs_index(unsigned int idx
)
420 if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL
, idx
))
425 static void xen_write_ldt_entry(struct desc_struct
*dt
, int entrynum
,
428 unsigned long lp
= (unsigned long)&dt
[entrynum
];
429 xmaddr_t mach_lp
= virt_to_machine(lp
);
430 u64 entry
= *(u64
*)ptr
;
435 if (HYPERVISOR_update_descriptor(mach_lp
.maddr
, entry
))
441 static int cvt_gate_to_trap(int vector
, const gate_desc
*val
,
442 struct trap_info
*info
)
444 if (val
->type
!= 0xf && val
->type
!= 0xe)
447 info
->vector
= vector
;
448 info
->address
= gate_offset(*val
);
449 info
->cs
= gate_segment(*val
);
450 info
->flags
= val
->dpl
;
451 /* interrupt gates clear IF */
452 if (val
->type
== 0xe)
458 /* Locations of each CPU's IDT */
459 static DEFINE_PER_CPU(struct desc_ptr
, idt_desc
);
461 /* Set an IDT entry. If the entry is part of the current IDT, then
463 static void xen_write_idt_entry(gate_desc
*dt
, int entrynum
, const gate_desc
*g
)
465 unsigned long p
= (unsigned long)&dt
[entrynum
];
466 unsigned long start
, end
;
470 start
= __get_cpu_var(idt_desc
).address
;
471 end
= start
+ __get_cpu_var(idt_desc
).size
+ 1;
475 native_write_idt_entry(dt
, entrynum
, g
);
477 if (p
>= start
&& (p
+ 8) <= end
) {
478 struct trap_info info
[2];
482 if (cvt_gate_to_trap(entrynum
, g
, &info
[0]))
483 if (HYPERVISOR_set_trap_table(info
))
490 static void xen_convert_trap_info(const struct desc_ptr
*desc
,
491 struct trap_info
*traps
)
493 unsigned in
, out
, count
;
495 count
= (desc
->size
+1) / sizeof(gate_desc
);
498 for (in
= out
= 0; in
< count
; in
++) {
499 gate_desc
*entry
= (gate_desc
*)(desc
->address
) + in
;
501 if (cvt_gate_to_trap(in
, entry
, &traps
[out
]))
504 traps
[out
].address
= 0;
507 void xen_copy_trap_info(struct trap_info
*traps
)
509 const struct desc_ptr
*desc
= &__get_cpu_var(idt_desc
);
511 xen_convert_trap_info(desc
, traps
);
514 /* Load a new IDT into Xen. In principle this can be per-CPU, so we
515 hold a spinlock to protect the static traps[] array (static because
516 it avoids allocation, and saves stack space). */
517 static void xen_load_idt(const struct desc_ptr
*desc
)
519 static DEFINE_SPINLOCK(lock
);
520 static struct trap_info traps
[257];
524 __get_cpu_var(idt_desc
) = *desc
;
526 xen_convert_trap_info(desc
, traps
);
529 if (HYPERVISOR_set_trap_table(traps
))
535 /* Write a GDT descriptor entry. Ignore LDT descriptors, since
536 they're handled differently. */
537 static void xen_write_gdt_entry(struct desc_struct
*dt
, int entry
,
538 const void *desc
, int type
)
549 xmaddr_t maddr
= virt_to_machine(&dt
[entry
]);
552 if (HYPERVISOR_update_descriptor(maddr
.maddr
, *(u64
*)desc
))
561 static void xen_load_sp0(struct tss_struct
*tss
,
562 struct thread_struct
*thread
)
564 struct multicall_space mcs
= xen_mc_entry(0);
565 MULTI_stack_switch(mcs
.mc
, __KERNEL_DS
, thread
->sp0
);
566 xen_mc_issue(PARAVIRT_LAZY_CPU
);
569 static void xen_set_iopl_mask(unsigned mask
)
571 struct physdev_set_iopl set_iopl
;
573 /* Force the change at ring 0. */
574 set_iopl
.iopl
= (mask
== 0) ? 1 : (mask
>> 12) & 3;
575 HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
578 static void xen_io_delay(void)
582 #ifdef CONFIG_X86_LOCAL_APIC
583 static u32
xen_apic_read(unsigned long reg
)
588 static void xen_apic_write(unsigned long reg
, u32 val
)
590 /* Warn to see if there's any stray references */
595 static void xen_flush_tlb(void)
597 struct mmuext_op
*op
;
598 struct multicall_space mcs
;
602 mcs
= xen_mc_entry(sizeof(*op
));
605 op
->cmd
= MMUEXT_TLB_FLUSH_LOCAL
;
606 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
608 xen_mc_issue(PARAVIRT_LAZY_MMU
);
613 static void xen_flush_tlb_single(unsigned long addr
)
615 struct mmuext_op
*op
;
616 struct multicall_space mcs
;
620 mcs
= xen_mc_entry(sizeof(*op
));
622 op
->cmd
= MMUEXT_INVLPG_LOCAL
;
623 op
->arg1
.linear_addr
= addr
& PAGE_MASK
;
624 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
626 xen_mc_issue(PARAVIRT_LAZY_MMU
);
631 static void xen_flush_tlb_others(const cpumask_t
*cpus
, struct mm_struct
*mm
,
638 cpumask_t cpumask
= *cpus
;
639 struct multicall_space mcs
;
642 * A couple of (to be removed) sanity checks:
644 * - current CPU must not be in mask
645 * - mask must exist :)
647 BUG_ON(cpus_empty(cpumask
));
648 BUG_ON(cpu_isset(smp_processor_id(), cpumask
));
651 /* If a CPU which we ran on has gone down, OK. */
652 cpus_and(cpumask
, cpumask
, cpu_online_map
);
653 if (cpus_empty(cpumask
))
656 mcs
= xen_mc_entry(sizeof(*args
));
658 args
->mask
= cpumask
;
659 args
->op
.arg2
.vcpumask
= &args
->mask
;
661 if (va
== TLB_FLUSH_ALL
) {
662 args
->op
.cmd
= MMUEXT_TLB_FLUSH_MULTI
;
664 args
->op
.cmd
= MMUEXT_INVLPG_MULTI
;
665 args
->op
.arg1
.linear_addr
= va
;
668 MULTI_mmuext_op(mcs
.mc
, &args
->op
, 1, NULL
, DOMID_SELF
);
670 xen_mc_issue(PARAVIRT_LAZY_MMU
);
673 static void xen_clts(void)
675 struct multicall_space mcs
;
677 mcs
= xen_mc_entry(0);
679 MULTI_fpu_taskswitch(mcs
.mc
, 0);
681 xen_mc_issue(PARAVIRT_LAZY_CPU
);
684 static void xen_write_cr0(unsigned long cr0
)
686 struct multicall_space mcs
;
688 /* Only pay attention to cr0.TS; everything else is
690 mcs
= xen_mc_entry(0);
692 MULTI_fpu_taskswitch(mcs
.mc
, (cr0
& X86_CR0_TS
) != 0);
694 xen_mc_issue(PARAVIRT_LAZY_CPU
);
697 static void xen_write_cr2(unsigned long cr2
)
699 x86_read_percpu(xen_vcpu
)->arch
.cr2
= cr2
;
702 static unsigned long xen_read_cr2(void)
704 return x86_read_percpu(xen_vcpu
)->arch
.cr2
;
707 static unsigned long xen_read_cr2_direct(void)
709 return x86_read_percpu(xen_vcpu_info
.arch
.cr2
);
712 static void xen_write_cr4(unsigned long cr4
)
717 native_write_cr4(cr4
);
720 static unsigned long xen_read_cr3(void)
722 return x86_read_percpu(xen_cr3
);
725 static void set_current_cr3(void *v
)
727 x86_write_percpu(xen_current_cr3
, (unsigned long)v
);
730 static void __xen_write_cr3(bool kernel
, unsigned long cr3
)
732 struct mmuext_op
*op
;
733 struct multicall_space mcs
;
737 mfn
= pfn_to_mfn(PFN_DOWN(cr3
));
741 WARN_ON(mfn
== 0 && kernel
);
743 mcs
= __xen_mc_entry(sizeof(*op
));
746 op
->cmd
= kernel
? MMUEXT_NEW_BASEPTR
: MMUEXT_NEW_USER_BASEPTR
;
749 MULTI_mmuext_op(mcs
.mc
, op
, 1, NULL
, DOMID_SELF
);
752 x86_write_percpu(xen_cr3
, cr3
);
754 /* Update xen_current_cr3 once the batch has actually
756 xen_mc_callback(set_current_cr3
, (void *)cr3
);
760 static void xen_write_cr3(unsigned long cr3
)
762 BUG_ON(preemptible());
764 xen_mc_batch(); /* disables interrupts */
766 /* Update while interrupts are disabled, so its atomic with
768 x86_write_percpu(xen_cr3
, cr3
);
770 __xen_write_cr3(true, cr3
);
774 pgd_t
*user_pgd
= xen_get_user_pgd(__va(cr3
));
776 __xen_write_cr3(false, __pa(user_pgd
));
778 __xen_write_cr3(false, 0);
782 xen_mc_issue(PARAVIRT_LAZY_CPU
); /* interrupts restored */
785 static int xen_write_msr_safe(unsigned int msr
, unsigned low
, unsigned high
)
796 case MSR_FS_BASE
: which
= SEGBASE_FS
; goto set
;
797 case MSR_KERNEL_GS_BASE
: which
= SEGBASE_GS_USER
; goto set
;
798 case MSR_GS_BASE
: which
= SEGBASE_GS_KERNEL
; goto set
;
801 base
= ((u64
)high
<< 32) | low
;
802 if (HYPERVISOR_set_segment_base(which
, base
) != 0)
807 ret
= native_write_msr_safe(msr
, low
, high
);
813 /* Early in boot, while setting up the initial pagetable, assume
814 everything is pinned. */
815 static __init
void xen_alloc_pte_init(struct mm_struct
*mm
, u32 pfn
)
817 #ifdef CONFIG_FLATMEM
818 BUG_ON(mem_map
); /* should only be used early */
820 make_lowmem_page_readonly(__va(PFN_PHYS(pfn
)));
823 /* Early release_pte assumes that all pts are pinned, since there's
824 only init_mm and anything attached to that is pinned. */
825 static void xen_release_pte_init(u32 pfn
)
827 make_lowmem_page_readwrite(__va(PFN_PHYS(pfn
)));
830 static void pin_pagetable_pfn(unsigned cmd
, unsigned long pfn
)
834 op
.arg1
.mfn
= pfn_to_mfn(pfn
);
835 if (HYPERVISOR_mmuext_op(&op
, 1, NULL
, DOMID_SELF
))
839 /* This needs to make sure the new pte page is pinned iff its being
840 attached to a pinned pagetable. */
841 static void xen_alloc_ptpage(struct mm_struct
*mm
, u32 pfn
, unsigned level
)
843 struct page
*page
= pfn_to_page(pfn
);
845 if (PagePinned(virt_to_page(mm
->pgd
))) {
848 if (!PageHighMem(page
)) {
849 make_lowmem_page_readonly(__va(PFN_PHYS(pfn
)));
851 pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE
, pfn
);
853 /* make sure there are no stray mappings of
859 static void xen_alloc_pte(struct mm_struct
*mm
, u32 pfn
)
861 xen_alloc_ptpage(mm
, pfn
, PT_PTE
);
864 static void xen_alloc_pmd(struct mm_struct
*mm
, u32 pfn
)
866 xen_alloc_ptpage(mm
, pfn
, PT_PMD
);
869 static int xen_pgd_alloc(struct mm_struct
*mm
)
871 pgd_t
*pgd
= mm
->pgd
;
874 BUG_ON(PagePinned(virt_to_page(pgd
)));
878 struct page
*page
= virt_to_page(pgd
);
881 BUG_ON(page
->private != 0);
885 user_pgd
= (pgd_t
*)__get_free_page(GFP_KERNEL
| __GFP_ZERO
);
886 page
->private = (unsigned long)user_pgd
;
888 if (user_pgd
!= NULL
) {
889 user_pgd
[pgd_index(VSYSCALL_START
)] =
890 __pgd(__pa(level3_user_vsyscall
) | _PAGE_TABLE
);
894 BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd
))));
901 static void xen_pgd_free(struct mm_struct
*mm
, pgd_t
*pgd
)
904 pgd_t
*user_pgd
= xen_get_user_pgd(pgd
);
907 free_page((unsigned long)user_pgd
);
911 /* This should never happen until we're OK to use struct page */
912 static void xen_release_ptpage(u32 pfn
, unsigned level
)
914 struct page
*page
= pfn_to_page(pfn
);
916 if (PagePinned(page
)) {
917 if (!PageHighMem(page
)) {
919 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE
, pfn
);
920 make_lowmem_page_readwrite(__va(PFN_PHYS(pfn
)));
922 ClearPagePinned(page
);
926 static void xen_release_pte(u32 pfn
)
928 xen_release_ptpage(pfn
, PT_PTE
);
931 static void xen_release_pmd(u32 pfn
)
933 xen_release_ptpage(pfn
, PT_PMD
);
936 #if PAGETABLE_LEVELS == 4
937 static void xen_alloc_pud(struct mm_struct
*mm
, u32 pfn
)
939 xen_alloc_ptpage(mm
, pfn
, PT_PUD
);
942 static void xen_release_pud(u32 pfn
)
944 xen_release_ptpage(pfn
, PT_PUD
);
948 #ifdef CONFIG_HIGHPTE
949 static void *xen_kmap_atomic_pte(struct page
*page
, enum km_type type
)
951 pgprot_t prot
= PAGE_KERNEL
;
953 if (PagePinned(page
))
954 prot
= PAGE_KERNEL_RO
;
956 if (0 && PageHighMem(page
))
957 printk("mapping highpte %lx type %d prot %s\n",
958 page_to_pfn(page
), type
,
959 (unsigned long)pgprot_val(prot
) & _PAGE_RW
? "WRITE" : "READ");
961 return kmap_atomic_prot(page
, type
, prot
);
965 static __init pte_t
mask_rw_pte(pte_t
*ptep
, pte_t pte
)
967 /* If there's an existing pte, then don't allow _PAGE_RW to be set */
968 if (pte_val_ma(*ptep
) & _PAGE_PRESENT
)
969 pte
= __pte_ma(((pte_val_ma(*ptep
) & _PAGE_RW
) | ~_PAGE_RW
) &
975 /* Init-time set_pte while constructing initial pagetables, which
976 doesn't allow RO pagetable pages to be remapped RW */
977 static __init
void xen_set_pte_init(pte_t
*ptep
, pte_t pte
)
979 pte
= mask_rw_pte(ptep
, pte
);
981 xen_set_pte(ptep
, pte
);
984 static __init
void xen_pagetable_setup_start(pgd_t
*base
)
988 void xen_setup_shared_info(void)
990 if (!xen_feature(XENFEAT_auto_translated_physmap
)) {
991 set_fixmap(FIX_PARAVIRT_BOOTMAP
,
992 xen_start_info
->shared_info
);
994 HYPERVISOR_shared_info
=
995 (struct shared_info
*)fix_to_virt(FIX_PARAVIRT_BOOTMAP
);
997 HYPERVISOR_shared_info
=
998 (struct shared_info
*)__va(xen_start_info
->shared_info
);
1001 /* In UP this is as good a place as any to set up shared info */
1002 xen_setup_vcpu_info_placement();
1005 xen_setup_mfn_list_list();
1008 static __init
void xen_pagetable_setup_done(pgd_t
*base
)
1010 xen_setup_shared_info();
1013 static __init
void xen_post_allocator_init(void)
1015 pv_mmu_ops
.set_pte
= xen_set_pte
;
1016 pv_mmu_ops
.set_pmd
= xen_set_pmd
;
1017 pv_mmu_ops
.set_pud
= xen_set_pud
;
1018 #if PAGETABLE_LEVELS == 4
1019 pv_mmu_ops
.set_pgd
= xen_set_pgd
;
1022 /* This will work as long as patching hasn't happened yet
1023 (which it hasn't) */
1024 pv_mmu_ops
.alloc_pte
= xen_alloc_pte
;
1025 pv_mmu_ops
.alloc_pmd
= xen_alloc_pmd
;
1026 pv_mmu_ops
.release_pte
= xen_release_pte
;
1027 pv_mmu_ops
.release_pmd
= xen_release_pmd
;
1028 #if PAGETABLE_LEVELS == 4
1029 pv_mmu_ops
.alloc_pud
= xen_alloc_pud
;
1030 pv_mmu_ops
.release_pud
= xen_release_pud
;
1033 #ifdef CONFIG_X86_64
1034 SetPagePinned(virt_to_page(level3_user_vsyscall
));
1036 xen_mark_init_mm_pinned();
1039 /* This is called once we have the cpu_possible_map */
1040 void xen_setup_vcpu_info_placement(void)
1044 for_each_possible_cpu(cpu
)
1045 xen_vcpu_setup(cpu
);
1047 /* xen_vcpu_setup managed to place the vcpu_info within the
1048 percpu area for all cpus, so make use of it */
1049 #ifdef CONFIG_X86_32
1050 if (have_vcpu_info_placement
) {
1051 printk(KERN_INFO
"Xen: using vcpu_info placement\n");
1053 pv_irq_ops
.save_fl
= xen_save_fl_direct
;
1054 pv_irq_ops
.restore_fl
= xen_restore_fl_direct
;
1055 pv_irq_ops
.irq_disable
= xen_irq_disable_direct
;
1056 pv_irq_ops
.irq_enable
= xen_irq_enable_direct
;
1057 pv_mmu_ops
.read_cr2
= xen_read_cr2_direct
;
1062 static unsigned xen_patch(u8 type
, u16 clobbers
, void *insnbuf
,
1063 unsigned long addr
, unsigned len
)
1065 char *start
, *end
, *reloc
;
1068 start
= end
= reloc
= NULL
;
1070 #define SITE(op, x) \
1071 case PARAVIRT_PATCH(op.x): \
1072 if (have_vcpu_info_placement) { \
1073 start = (char *)xen_##x##_direct; \
1074 end = xen_##x##_direct_end; \
1075 reloc = xen_##x##_direct_reloc; \
1080 #ifdef CONFIG_X86_32
1081 SITE(pv_irq_ops
, irq_enable
);
1082 SITE(pv_irq_ops
, irq_disable
);
1083 SITE(pv_irq_ops
, save_fl
);
1084 SITE(pv_irq_ops
, restore_fl
);
1085 #endif /* CONFIG_X86_32 */
1089 if (start
== NULL
|| (end
-start
) > len
)
1092 ret
= paravirt_patch_insns(insnbuf
, len
, start
, end
);
1094 /* Note: because reloc is assigned from something that
1095 appears to be an array, gcc assumes it's non-null,
1096 but doesn't know its relationship with start and
1098 if (reloc
> start
&& reloc
< end
) {
1099 int reloc_off
= reloc
- start
;
1100 long *relocp
= (long *)(insnbuf
+ reloc_off
);
1101 long delta
= start
- (char *)addr
;
1109 ret
= paravirt_patch_default(type
, clobbers
, insnbuf
,
1117 static void xen_set_fixmap(unsigned idx
, unsigned long phys
, pgprot_t prot
)
1121 phys
>>= PAGE_SHIFT
;
1124 case FIX_BTMAP_END
... FIX_BTMAP_BEGIN
:
1125 #ifdef CONFIG_X86_F00F_BUG
1128 #ifdef CONFIG_X86_32
1131 # ifdef CONFIG_HIGHMEM
1132 case FIX_KMAP_BEGIN
... FIX_KMAP_END
:
1135 case VSYSCALL_LAST_PAGE
... VSYSCALL_FIRST_PAGE
:
1137 #ifdef CONFIG_X86_LOCAL_APIC
1138 case FIX_APIC_BASE
: /* maps dummy local APIC */
1140 pte
= pfn_pte(phys
, prot
);
1144 pte
= mfn_pte(phys
, prot
);
1148 __native_set_fixmap(idx
, pte
);
1150 #ifdef CONFIG_X86_64
1151 /* Replicate changes to map the vsyscall page into the user
1152 pagetable vsyscall mapping. */
1153 if (idx
>= VSYSCALL_LAST_PAGE
&& idx
<= VSYSCALL_FIRST_PAGE
) {
1154 unsigned long vaddr
= __fix_to_virt(idx
);
1155 set_pte_vaddr_pud(level3_user_vsyscall
, vaddr
, pte
);
1160 static const struct pv_info xen_info __initdata
= {
1161 .paravirt_enabled
= 1,
1162 .shared_kernel_pmd
= 0,
1167 static const struct pv_init_ops xen_init_ops __initdata
= {
1170 .banner
= xen_banner
,
1171 .memory_setup
= xen_memory_setup
,
1172 .arch_setup
= xen_arch_setup
,
1173 .post_allocator_init
= xen_post_allocator_init
,
1176 static const struct pv_time_ops xen_time_ops __initdata
= {
1177 .time_init
= xen_time_init
,
1179 .set_wallclock
= xen_set_wallclock
,
1180 .get_wallclock
= xen_get_wallclock
,
1181 .get_tsc_khz
= xen_tsc_khz
,
1182 .sched_clock
= xen_sched_clock
,
1185 static const struct pv_cpu_ops xen_cpu_ops __initdata
= {
1188 .set_debugreg
= xen_set_debugreg
,
1189 .get_debugreg
= xen_get_debugreg
,
1193 .read_cr0
= native_read_cr0
,
1194 .write_cr0
= xen_write_cr0
,
1196 .read_cr4
= native_read_cr4
,
1197 .read_cr4_safe
= native_read_cr4_safe
,
1198 .write_cr4
= xen_write_cr4
,
1200 .wbinvd
= native_wbinvd
,
1202 .read_msr
= native_read_msr_safe
,
1203 .write_msr
= xen_write_msr_safe
,
1204 .read_tsc
= native_read_tsc
,
1205 .read_pmc
= native_read_pmc
,
1208 .irq_enable_sysexit
= xen_sysexit
,
1209 #ifdef CONFIG_X86_64
1210 .usergs_sysret32
= xen_sysret32
,
1211 .usergs_sysret64
= xen_sysret64
,
1214 .load_tr_desc
= paravirt_nop
,
1215 .set_ldt
= xen_set_ldt
,
1216 .load_gdt
= xen_load_gdt
,
1217 .load_idt
= xen_load_idt
,
1218 .load_tls
= xen_load_tls
,
1219 #ifdef CONFIG_X86_64
1220 .load_gs_index
= xen_load_gs_index
,
1223 .store_gdt
= native_store_gdt
,
1224 .store_idt
= native_store_idt
,
1225 .store_tr
= xen_store_tr
,
1227 .write_ldt_entry
= xen_write_ldt_entry
,
1228 .write_gdt_entry
= xen_write_gdt_entry
,
1229 .write_idt_entry
= xen_write_idt_entry
,
1230 .load_sp0
= xen_load_sp0
,
1232 .set_iopl_mask
= xen_set_iopl_mask
,
1233 .io_delay
= xen_io_delay
,
1235 /* Xen takes care of %gs when switching to usermode for us */
1236 .swapgs
= paravirt_nop
,
1239 .enter
= paravirt_enter_lazy_cpu
,
1240 .leave
= xen_leave_lazy
,
1244 static void __init
__xen_init_IRQ(void)
1246 #ifdef CONFIG_X86_64
1249 /* Create identity vector->irq map */
1250 for(i
= 0; i
< NR_VECTORS
; i
++) {
1253 for_each_possible_cpu(cpu
)
1254 per_cpu(vector_irq
, cpu
)[i
] = i
;
1256 #endif /* CONFIG_X86_64 */
1261 static const struct pv_irq_ops xen_irq_ops __initdata
= {
1262 .init_IRQ
= __xen_init_IRQ
,
1263 .save_fl
= xen_save_fl
,
1264 .restore_fl
= xen_restore_fl
,
1265 .irq_disable
= xen_irq_disable
,
1266 .irq_enable
= xen_irq_enable
,
1267 .safe_halt
= xen_safe_halt
,
1269 #ifdef CONFIG_X86_64
1270 .adjust_exception_frame
= xen_adjust_exception_frame
,
1274 static const struct pv_apic_ops xen_apic_ops __initdata
= {
1275 #ifdef CONFIG_X86_LOCAL_APIC
1276 .apic_write
= xen_apic_write
,
1277 .apic_read
= xen_apic_read
,
1278 .setup_boot_clock
= paravirt_nop
,
1279 .setup_secondary_clock
= paravirt_nop
,
1280 .startup_ipi_hook
= paravirt_nop
,
1284 static const struct pv_mmu_ops xen_mmu_ops __initdata
= {
1285 .pagetable_setup_start
= xen_pagetable_setup_start
,
1286 .pagetable_setup_done
= xen_pagetable_setup_done
,
1288 .read_cr2
= xen_read_cr2
,
1289 .write_cr2
= xen_write_cr2
,
1291 .read_cr3
= xen_read_cr3
,
1292 .write_cr3
= xen_write_cr3
,
1294 .flush_tlb_user
= xen_flush_tlb
,
1295 .flush_tlb_kernel
= xen_flush_tlb
,
1296 .flush_tlb_single
= xen_flush_tlb_single
,
1297 .flush_tlb_others
= xen_flush_tlb_others
,
1299 .pte_update
= paravirt_nop
,
1300 .pte_update_defer
= paravirt_nop
,
1302 .pgd_alloc
= xen_pgd_alloc
,
1303 .pgd_free
= xen_pgd_free
,
1305 .alloc_pte
= xen_alloc_pte_init
,
1306 .release_pte
= xen_release_pte_init
,
1307 .alloc_pmd
= xen_alloc_pte_init
,
1308 .alloc_pmd_clone
= paravirt_nop
,
1309 .release_pmd
= xen_release_pte_init
,
1311 #ifdef CONFIG_HIGHPTE
1312 .kmap_atomic_pte
= xen_kmap_atomic_pte
,
1315 #ifdef CONFIG_X86_64
1316 .set_pte
= xen_set_pte
,
1318 .set_pte
= xen_set_pte_init
,
1320 .set_pte_at
= xen_set_pte_at
,
1321 .set_pmd
= xen_set_pmd_hyper
,
1323 .ptep_modify_prot_start
= __ptep_modify_prot_start
,
1324 .ptep_modify_prot_commit
= __ptep_modify_prot_commit
,
1326 .pte_val
= xen_pte_val
,
1327 .pte_flags
= native_pte_val
,
1328 .pgd_val
= xen_pgd_val
,
1330 .make_pte
= xen_make_pte
,
1331 .make_pgd
= xen_make_pgd
,
1333 #ifdef CONFIG_X86_PAE
1334 .set_pte_atomic
= xen_set_pte_atomic
,
1335 .set_pte_present
= xen_set_pte_at
,
1336 .pte_clear
= xen_pte_clear
,
1337 .pmd_clear
= xen_pmd_clear
,
1338 #endif /* CONFIG_X86_PAE */
1339 .set_pud
= xen_set_pud_hyper
,
1341 .make_pmd
= xen_make_pmd
,
1342 .pmd_val
= xen_pmd_val
,
1344 #if PAGETABLE_LEVELS == 4
1345 .pud_val
= xen_pud_val
,
1346 .make_pud
= xen_make_pud
,
1347 .set_pgd
= xen_set_pgd_hyper
,
1349 .alloc_pud
= xen_alloc_pte_init
,
1350 .release_pud
= xen_release_pte_init
,
1351 #endif /* PAGETABLE_LEVELS == 4 */
1353 .activate_mm
= xen_activate_mm
,
1354 .dup_mmap
= xen_dup_mmap
,
1355 .exit_mmap
= xen_exit_mmap
,
1358 .enter
= paravirt_enter_lazy_mmu
,
1359 .leave
= xen_leave_lazy
,
1362 .set_fixmap
= xen_set_fixmap
,
1365 static void xen_reboot(int reason
)
1367 struct sched_shutdown r
= { .reason
= reason
};
1373 if (HYPERVISOR_sched_op(SCHEDOP_shutdown
, &r
))
1377 static void xen_restart(char *msg
)
1379 xen_reboot(SHUTDOWN_reboot
);
1382 static void xen_emergency_restart(void)
1384 xen_reboot(SHUTDOWN_reboot
);
1387 static void xen_machine_halt(void)
1389 xen_reboot(SHUTDOWN_poweroff
);
1392 static void xen_crash_shutdown(struct pt_regs
*regs
)
1394 xen_reboot(SHUTDOWN_crash
);
1397 static const struct machine_ops __initdata xen_machine_ops
= {
1398 .restart
= xen_restart
,
1399 .halt
= xen_machine_halt
,
1400 .power_off
= xen_machine_halt
,
1401 .shutdown
= xen_machine_halt
,
1402 .crash_shutdown
= xen_crash_shutdown
,
1403 .emergency_restart
= xen_emergency_restart
,
1407 static void __init
xen_reserve_top(void)
1409 #ifdef CONFIG_X86_32
1410 unsigned long top
= HYPERVISOR_VIRT_START
;
1411 struct xen_platform_parameters pp
;
1413 if (HYPERVISOR_xen_version(XENVER_platform_parameters
, &pp
) == 0)
1414 top
= pp
.virt_start
;
1416 reserve_top_address(-top
+ 2 * PAGE_SIZE
);
1417 #endif /* CONFIG_X86_32 */
1421 * Like __va(), but returns address in the kernel mapping (which is
1422 * all we have until the physical memory mapping has been set up.
1424 static void *__ka(phys_addr_t paddr
)
1426 #ifdef CONFIG_X86_64
1427 return (void *)(paddr
+ __START_KERNEL_map
);
1433 /* Convert a machine address to physical address */
1434 static unsigned long m2p(phys_addr_t maddr
)
1438 maddr
&= PTE_PFN_MASK
;
1439 paddr
= mfn_to_pfn(maddr
>> PAGE_SHIFT
) << PAGE_SHIFT
;
1444 /* Convert a machine address to kernel virtual */
1445 static void *m2v(phys_addr_t maddr
)
1447 return __ka(m2p(maddr
));
1450 #ifdef CONFIG_X86_64
1451 static void walk(pgd_t
*pgd
, unsigned long addr
)
1453 unsigned l4idx
= pgd_index(addr
);
1454 unsigned l3idx
= pud_index(addr
);
1455 unsigned l2idx
= pmd_index(addr
);
1456 unsigned l1idx
= pte_index(addr
);
1462 xen_raw_printk("walk %p, %lx -> %d %d %d %d\n",
1463 pgd
, addr
, l4idx
, l3idx
, l2idx
, l1idx
);
1466 xen_raw_printk(" l4: %016lx\n", l4
.pgd
);
1467 xen_raw_printk(" %016lx\n", pgd_val(l4
));
1469 l3
= ((pud_t
*)(m2v(l4
.pgd
)))[l3idx
];
1470 xen_raw_printk(" l3: %016lx\n", l3
.pud
);
1471 xen_raw_printk(" %016lx\n", pud_val(l3
));
1473 l2
= ((pmd_t
*)(m2v(l3
.pud
)))[l2idx
];
1474 xen_raw_printk(" l2: %016lx\n", l2
.pmd
);
1475 xen_raw_printk(" %016lx\n", pmd_val(l2
));
1477 l1
= ((pte_t
*)(m2v(l2
.pmd
)))[l1idx
];
1478 xen_raw_printk(" l1: %016lx\n", l1
.pte
);
1479 xen_raw_printk(" %016lx\n", pte_val(l1
));
1483 static void set_page_prot(void *addr
, pgprot_t prot
)
1485 unsigned long pfn
= __pa(addr
) >> PAGE_SHIFT
;
1486 pte_t pte
= pfn_pte(pfn
, prot
);
1488 xen_raw_printk("addr=%p pfn=%lx mfn=%lx prot=%016llx pte=%016llx\n",
1489 addr
, pfn
, get_phys_to_machine(pfn
),
1490 pgprot_val(prot
), pte
.pte
);
1492 if (HYPERVISOR_update_va_mapping((unsigned long)addr
, pte
, 0))
1496 static __init
void xen_map_identity_early(pmd_t
*pmd
, unsigned long max_pfn
)
1498 unsigned pmdidx
, pteidx
;
1504 for(pmdidx
= 0; pmdidx
< PTRS_PER_PMD
&& pfn
< max_pfn
; pmdidx
++) {
1507 /* Reuse or allocate a page of ptes */
1508 if (pmd_present(pmd
[pmdidx
]))
1509 pte_page
= m2v(pmd
[pmdidx
].pmd
);
1511 /* Check for free pte pages */
1512 if (ident_pte
== ARRAY_SIZE(level1_ident_pgt
))
1515 pte_page
= &level1_ident_pgt
[ident_pte
];
1516 ident_pte
+= PTRS_PER_PTE
;
1518 pmd
[pmdidx
] = __pmd(__pa(pte_page
) | _PAGE_TABLE
);
1521 /* Install mappings */
1522 for(pteidx
= 0; pteidx
< PTRS_PER_PTE
; pteidx
++, pfn
++) {
1525 if (pfn
> max_pfn_mapped
)
1526 max_pfn_mapped
= pfn
;
1528 if (!pte_none(pte_page
[pteidx
]))
1531 pte
= pfn_pte(pfn
, PAGE_KERNEL_EXEC
);
1532 pte_page
[pteidx
] = pte
;
1536 for(pteidx
= 0; pteidx
< ident_pte
; pteidx
+= PTRS_PER_PTE
)
1537 set_page_prot(&level1_ident_pgt
[pteidx
], PAGE_KERNEL_RO
);
1539 set_page_prot(pmd
, PAGE_KERNEL_RO
);
1542 #ifdef CONFIG_X86_64
1543 static void convert_pfn_mfn(void *v
)
1548 /* All levels are converted the same way, so just treat them
1550 for(i
= 0; i
< PTRS_PER_PTE
; i
++)
1551 pte
[i
] = xen_make_pte(pte
[i
].pte
);
1555 * Set up the inital kernel pagetable.
1557 * We can construct this by grafting the Xen provided pagetable into
1558 * head_64.S's preconstructed pagetables. We copy the Xen L2's into
1559 * level2_ident_pgt, level2_kernel_pgt and level2_fixmap_pgt. This
1560 * means that only the kernel has a physical mapping to start with -
1561 * but that's enough to get __va working. We need to fill in the rest
1562 * of the physical mapping once some sort of allocator has been set
1565 static __init pgd_t
*xen_setup_kernel_pagetable(pgd_t
*pgd
, unsigned long max_pfn
)
1570 /* Zap identity mapping */
1571 init_level4_pgt
[0] = __pgd(0);
1573 /* Pre-constructed entries are in pfn, so convert to mfn */
1574 convert_pfn_mfn(init_level4_pgt
);
1575 convert_pfn_mfn(level3_ident_pgt
);
1576 convert_pfn_mfn(level3_kernel_pgt
);
1578 l3
= m2v(pgd
[pgd_index(__START_KERNEL_map
)].pgd
);
1579 l2
= m2v(l3
[pud_index(__START_KERNEL_map
)].pud
);
1581 memcpy(level2_ident_pgt
, l2
, sizeof(pmd_t
) * PTRS_PER_PMD
);
1582 memcpy(level2_kernel_pgt
, l2
, sizeof(pmd_t
) * PTRS_PER_PMD
);
1584 l3
= m2v(pgd
[pgd_index(__START_KERNEL_map
+ PMD_SIZE
)].pgd
);
1585 l2
= m2v(l3
[pud_index(__START_KERNEL_map
+ PMD_SIZE
)].pud
);
1586 memcpy(level2_fixmap_pgt
, l2
, sizeof(pmd_t
) * PTRS_PER_PMD
);
1588 /* Set up identity map */
1589 xen_map_identity_early(level2_ident_pgt
, max_pfn
);
1591 /* Make pagetable pieces RO */
1592 set_page_prot(init_level4_pgt
, PAGE_KERNEL_RO
);
1593 set_page_prot(level3_ident_pgt
, PAGE_KERNEL_RO
);
1594 set_page_prot(level3_kernel_pgt
, PAGE_KERNEL_RO
);
1595 set_page_prot(level3_user_vsyscall
, PAGE_KERNEL_RO
);
1596 set_page_prot(level2_kernel_pgt
, PAGE_KERNEL_RO
);
1597 set_page_prot(level2_fixmap_pgt
, PAGE_KERNEL_RO
);
1599 /* Pin down new L4 */
1600 pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE
,
1601 PFN_DOWN(__pa_symbol(init_level4_pgt
)));
1603 /* Unpin Xen-provided one */
1604 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE
, PFN_DOWN(__pa(pgd
)));
1607 pgd
= init_level4_pgt
;
1610 * At this stage there can be no user pgd, and no page
1611 * structure to attach it to, so make sure we just set kernel
1615 __xen_write_cr3(true, __pa(pgd
));
1616 xen_mc_issue(PARAVIRT_LAZY_CPU
);
1618 reserve_early(__pa(xen_start_info
->pt_base
),
1619 __pa(xen_start_info
->pt_base
+
1620 xen_start_info
->nr_pt_frames
* PAGE_SIZE
),
1625 #else /* !CONFIG_X86_64 */
1626 static pmd_t level2_kernel_pgt
[PTRS_PER_PMD
] __page_aligned_bss
;
1628 static __init pgd_t
*xen_setup_kernel_pagetable(pgd_t
*pgd
, unsigned long max_pfn
)
1632 init_pg_tables_start
= __pa(pgd
);
1633 init_pg_tables_end
= __pa(pgd
) + xen_start_info
->nr_pt_frames
*PAGE_SIZE
;
1634 max_pfn_mapped
= PFN_DOWN(init_pg_tables_end
+ 512*1024);
1636 kernel_pmd
= m2v(pgd
[KERNEL_PGD_BOUNDARY
].pgd
);
1637 memcpy(level2_kernel_pgt
, kernel_pmd
, sizeof(pmd_t
) * PTRS_PER_PMD
);
1639 xen_map_identity_early(level2_kernel_pgt
, max_pfn
);
1641 memcpy(swapper_pg_dir
, pgd
, sizeof(pgd_t
) * PTRS_PER_PGD
);
1642 set_pgd(&swapper_pg_dir
[KERNEL_PGD_BOUNDARY
],
1643 __pgd(__pa(level2_kernel_pgt
) | _PAGE_PRESENT
));
1645 set_page_prot(level2_kernel_pgt
, PAGE_KERNEL_RO
);
1646 set_page_prot(swapper_pg_dir
, PAGE_KERNEL_RO
);
1647 set_page_prot(empty_zero_page
, PAGE_KERNEL_RO
);
1649 pin_pagetable_pfn(MMUEXT_UNPIN_TABLE
, PFN_DOWN(__pa(pgd
)));
1651 xen_write_cr3(__pa(swapper_pg_dir
));
1653 pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE
, PFN_DOWN(__pa(swapper_pg_dir
)));
1655 return swapper_pg_dir
;
1657 #endif /* CONFIG_X86_64 */
1659 /* First C function to be called on Xen boot */
1660 asmlinkage
void __init
xen_start_kernel(void)
1664 if (!xen_start_info
)
1667 BUG_ON(memcmp(xen_start_info
->magic
, "xen-3", 5) != 0);
1669 xen_setup_features();
1671 /* Install Xen paravirt ops */
1673 pv_init_ops
= xen_init_ops
;
1674 pv_time_ops
= xen_time_ops
;
1675 pv_cpu_ops
= xen_cpu_ops
;
1676 pv_irq_ops
= xen_irq_ops
;
1677 pv_apic_ops
= xen_apic_ops
;
1678 pv_mmu_ops
= xen_mmu_ops
;
1680 if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad
)) {
1681 pv_mmu_ops
.ptep_modify_prot_start
= xen_ptep_modify_prot_start
;
1682 pv_mmu_ops
.ptep_modify_prot_commit
= xen_ptep_modify_prot_commit
;
1685 machine_ops
= xen_machine_ops
;
1687 #ifdef CONFIG_X86_64
1688 /* Disable until direct per-cpu data access. */
1689 have_vcpu_info_placement
= 0;
1696 if (!xen_feature(XENFEAT_auto_translated_physmap
))
1697 xen_build_dynamic_phys_to_machine();
1699 pgd
= (pgd_t
*)xen_start_info
->pt_base
;
1701 /* Prevent unwanted bits from being set in PTEs. */
1702 __supported_pte_mask
&= ~_PAGE_GLOBAL
;
1703 if (!is_initial_xendomain())
1704 __supported_pte_mask
&= ~(_PAGE_PWT
| _PAGE_PCD
);
1706 /* Don't do the full vcpu_info placement stuff until we have a
1707 possible map and a non-dummy shared_info. */
1708 per_cpu(xen_vcpu
, 0) = &HYPERVISOR_shared_info
->vcpu_info
[0];
1710 xen_raw_console_write("mapping kernel into physical memory\n");
1711 pgd
= xen_setup_kernel_pagetable(pgd
, xen_start_info
->nr_pages
);
1715 /* keep using Xen gdt for now; no urgent need to change it */
1717 pv_info
.kernel_rpl
= 1;
1718 if (xen_feature(XENFEAT_supervisor_mode_kernel
))
1719 pv_info
.kernel_rpl
= 0;
1721 /* set the limit of our address space */
1724 #ifdef CONFIG_X86_32
1725 /* set up basic CPUID stuff */
1726 cpu_detect(&new_cpu_data
);
1727 new_cpu_data
.hard_math
= 1;
1728 new_cpu_data
.x86_capability
[0] = cpuid_edx(1);
1731 /* Poke various useful things into boot_params */
1732 boot_params
.hdr
.type_of_loader
= (9 << 4) | 0;
1733 boot_params
.hdr
.ramdisk_image
= xen_start_info
->mod_start
1734 ? __pa(xen_start_info
->mod_start
) : 0;
1735 boot_params
.hdr
.ramdisk_size
= xen_start_info
->mod_len
;
1736 boot_params
.hdr
.cmd_line_ptr
= __pa(xen_start_info
->cmd_line
);
1738 if (!is_initial_xendomain()) {
1739 add_preferred_console("xenboot", 0, NULL
);
1740 add_preferred_console("tty", 0, NULL
);
1741 add_preferred_console("hvc", 0, NULL
);
1744 xen_raw_console_write("about to get started...\n");
1747 xen_raw_printk("&boot_params=%p __pa(&boot_params)=%lx __va(__pa(&boot_params))=%lx\n",
1748 &boot_params
, __pa_symbol(&boot_params
),
1749 __va(__pa_symbol(&boot_params
)));
1751 walk(pgd
, &boot_params
);
1752 walk(pgd
, __va(__pa(&boot_params
)));
1755 /* Start the world */
1756 #ifdef CONFIG_X86_32
1757 i386_start_kernel();
1759 x86_64_start_reservations((char *)__pa_symbol(&boot_params
));