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linux-sg2042/arch/x86/xen/enlighten.c

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/*
* Core of Xen paravirt_ops implementation.
*
* This file contains the xen_paravirt_ops structure itself, and the
* implementations for:
* - privileged instructions
* - interrupt flags
* - segment operations
* - booting and setup
*
* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/preempt.h>
#include <linux/hardirq.h>
#include <linux/percpu.h>
#include <linux/delay.h>
#include <linux/start_kernel.h>
#include <linux/sched.h>
#include <linux/bootmem.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/page-flags.h>
#include <linux/highmem.h>
#include <linux/console.h>
#include <xen/interface/xen.h>
#include <xen/interface/physdev.h>
#include <xen/interface/vcpu.h>
#include <xen/interface/sched.h>
#include <xen/features.h>
#include <xen/page.h>
#include <xen/hvc-console.h>
#include <asm/paravirt.h>
#include <asm/page.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
#include <asm/fixmap.h>
#include <asm/processor.h>
#include <asm/msr-index.h>
#include <asm/setup.h>
#include <asm/desc.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/reboot.h>
#include "xen-ops.h"
#include "mmu.h"
#include "multicalls.h"
EXPORT_SYMBOL_GPL(hypercall_page);
DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
/*
* Identity map, in addition to plain kernel map. This needs to be
* large enough to allocate page table pages to allocate the rest.
* Each page can map 2MB.
*/
static pte_t level1_ident_pgt[PTRS_PER_PTE * 4] __page_aligned_bss;
#ifdef CONFIG_X86_64
/* l3 pud for userspace vsyscall mapping */
static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss;
#endif /* CONFIG_X86_64 */
/*
* Note about cr3 (pagetable base) values:
*
* xen_cr3 contains the current logical cr3 value; it contains the
* last set cr3. This may not be the current effective cr3, because
* its update may be being lazily deferred. However, a vcpu looking
* at its own cr3 can use this value knowing that it everything will
* be self-consistent.
*
* xen_current_cr3 contains the actual vcpu cr3; it is set once the
* hypercall to set the vcpu cr3 is complete (so it may be a little
* out of date, but it will never be set early). If one vcpu is
* looking at another vcpu's cr3 value, it should use this variable.
*/
DEFINE_PER_CPU(unsigned long, xen_cr3); /* cr3 stored as physaddr */
DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */
struct start_info *xen_start_info;
EXPORT_SYMBOL_GPL(xen_start_info);
struct shared_info xen_dummy_shared_info;
/*
* Point at some empty memory to start with. We map the real shared_info
* page as soon as fixmap is up and running.
*/
struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
/*
* Flag to determine whether vcpu info placement is available on all
* VCPUs. We assume it is to start with, and then set it to zero on
* the first failure. This is because it can succeed on some VCPUs
* and not others, since it can involve hypervisor memory allocation,
* or because the guest failed to guarantee all the appropriate
* constraints on all VCPUs (ie buffer can't cross a page boundary).
*
* Note that any particular CPU may be using a placed vcpu structure,
* but we can only optimise if the all are.
*
* 0: not available, 1: available
*/
static int have_vcpu_info_placement = 1;
static void xen_vcpu_setup(int cpu)
{
struct vcpu_register_vcpu_info info;
int err;
struct vcpu_info *vcpup;
BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
if (!have_vcpu_info_placement)
return; /* already tested, not available */
vcpup = &per_cpu(xen_vcpu_info, cpu);
info.mfn = virt_to_mfn(vcpup);
info.offset = offset_in_page(vcpup);
printk(KERN_DEBUG "trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
cpu, vcpup, info.mfn, info.offset);
/* Check to see if the hypervisor will put the vcpu_info
structure where we want it, which allows direct access via
a percpu-variable. */
err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
if (err) {
printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
have_vcpu_info_placement = 0;
} else {
/* This cpu is using the registered vcpu info, even if
later ones fail to. */
per_cpu(xen_vcpu, cpu) = vcpup;
printk(KERN_DEBUG "cpu %d using vcpu_info at %p\n",
cpu, vcpup);
}
}
/*
* On restore, set the vcpu placement up again.
* If it fails, then we're in a bad state, since
* we can't back out from using it...
*/
void xen_vcpu_restore(void)
{
if (have_vcpu_info_placement) {
int cpu;
for_each_online_cpu(cpu) {
bool other_cpu = (cpu != smp_processor_id());
if (other_cpu &&
HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL))
BUG();
xen_vcpu_setup(cpu);
if (other_cpu &&
HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL))
BUG();
}
BUG_ON(!have_vcpu_info_placement);
}
}
static void __init xen_banner(void)
{
unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
struct xen_extraversion extra;
HYPERVISOR_xen_version(XENVER_extraversion, &extra);
printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
pv_info.name);
printk(KERN_INFO "Xen version: %d.%d%s%s\n",
version >> 16, version & 0xffff, extra.extraversion,
xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
}
static void xen_cpuid(unsigned int *ax, unsigned int *bx,
unsigned int *cx, unsigned int *dx)
{
unsigned maskedx = ~0;
/*
* Mask out inconvenient features, to try and disable as many
* unsupported kernel subsystems as possible.
*/
if (*ax == 1)
maskedx = ~((1 << X86_FEATURE_APIC) | /* disable APIC */
(1 << X86_FEATURE_ACPI) | /* disable ACPI */
(1 << X86_FEATURE_MCE) | /* disable MCE */
(1 << X86_FEATURE_MCA) | /* disable MCA */
(1 << X86_FEATURE_ACC)); /* thermal monitoring */
asm(XEN_EMULATE_PREFIX "cpuid"
: "=a" (*ax),
"=b" (*bx),
"=c" (*cx),
"=d" (*dx)
: "0" (*ax), "2" (*cx));
*dx &= maskedx;
}
static void xen_set_debugreg(int reg, unsigned long val)
{
HYPERVISOR_set_debugreg(reg, val);
}
static unsigned long xen_get_debugreg(int reg)
{
return HYPERVISOR_get_debugreg(reg);
}
static unsigned long xen_save_fl(void)
{
struct vcpu_info *vcpu;
unsigned long flags;
vcpu = x86_read_percpu(xen_vcpu);
/* flag has opposite sense of mask */
flags = !vcpu->evtchn_upcall_mask;
/* convert to IF type flag
-0 -> 0x00000000
-1 -> 0xffffffff
*/
return (-flags) & X86_EFLAGS_IF;
}
static void xen_restore_fl(unsigned long flags)
{
struct vcpu_info *vcpu;
/* convert from IF type flag */
flags = !(flags & X86_EFLAGS_IF);
/* There's a one instruction preempt window here. We need to
make sure we're don't switch CPUs between getting the vcpu
pointer and updating the mask. */
preempt_disable();
vcpu = x86_read_percpu(xen_vcpu);
vcpu->evtchn_upcall_mask = flags;
preempt_enable_no_resched();
/* Doesn't matter if we get preempted here, because any
pending event will get dealt with anyway. */
if (flags == 0) {
preempt_check_resched();
barrier(); /* unmask then check (avoid races) */
if (unlikely(vcpu->evtchn_upcall_pending))
force_evtchn_callback();
}
}
static void xen_irq_disable(void)
{
/* There's a one instruction preempt window here. We need to
make sure we're don't switch CPUs between getting the vcpu
pointer and updating the mask. */
preempt_disable();
x86_read_percpu(xen_vcpu)->evtchn_upcall_mask = 1;
preempt_enable_no_resched();
}
static void xen_irq_enable(void)
{
struct vcpu_info *vcpu;
/* We don't need to worry about being preempted here, since
either a) interrupts are disabled, so no preemption, or b)
the caller is confused and is trying to re-enable interrupts
on an indeterminate processor. */
vcpu = x86_read_percpu(xen_vcpu);
vcpu->evtchn_upcall_mask = 0;
/* Doesn't matter if we get preempted here, because any
pending event will get dealt with anyway. */
barrier(); /* unmask then check (avoid races) */
if (unlikely(vcpu->evtchn_upcall_pending))
force_evtchn_callback();
}
static void xen_safe_halt(void)
{
/* Blocking includes an implicit local_irq_enable(). */
if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0)
BUG();
}
static void xen_halt(void)
{
if (irqs_disabled())
HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
else
xen_safe_halt();
}
static void xen_leave_lazy(void)
{
paravirt_leave_lazy(paravirt_get_lazy_mode());
xen_mc_flush();
}
static unsigned long xen_store_tr(void)
{
return 0;
}
static void xen_set_ldt(const void *addr, unsigned entries)
{
struct mmuext_op *op;
struct multicall_space mcs = xen_mc_entry(sizeof(*op));
op = mcs.args;
op->cmd = MMUEXT_SET_LDT;
op->arg1.linear_addr = (unsigned long)addr;
op->arg2.nr_ents = entries;
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
static void xen_load_gdt(const struct desc_ptr *dtr)
{
unsigned long *frames;
unsigned long va = dtr->address;
unsigned int size = dtr->size + 1;
unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
int f;
struct multicall_space mcs;
/* A GDT can be up to 64k in size, which corresponds to 8192
8-byte entries, or 16 4k pages.. */
BUG_ON(size > 65536);
BUG_ON(va & ~PAGE_MASK);
mcs = xen_mc_entry(sizeof(*frames) * pages);
frames = mcs.args;
for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
frames[f] = virt_to_mfn(va);
make_lowmem_page_readonly((void *)va);
}
MULTI_set_gdt(mcs.mc, frames, size / sizeof(struct desc_struct));
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
static void load_TLS_descriptor(struct thread_struct *t,
unsigned int cpu, unsigned int i)
{
struct desc_struct *gdt = get_cpu_gdt_table(cpu);
xmaddr_t maddr = virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
struct multicall_space mc = __xen_mc_entry(0);
MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
}
static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
{
/*
* XXX sleazy hack: If we're being called in a lazy-cpu zone,
* it means we're in a context switch, and %gs has just been
* saved. This means we can zero it out to prevent faults on
* exit from the hypervisor if the next process has no %gs.
* Either way, it has been saved, and the new value will get
* loaded properly. This will go away as soon as Xen has been
* modified to not save/restore %gs for normal hypercalls.
*
* On x86_64, this hack is not used for %gs, because gs points
* to KERNEL_GS_BASE (and uses it for PDA references), so we
* must not zero %gs on x86_64
*
* For x86_64, we need to zero %fs, otherwise we may get an
* exception between the new %fs descriptor being loaded and
* %fs being effectively cleared at __switch_to().
*/
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
#ifdef CONFIG_X86_32
loadsegment(gs, 0);
#else
loadsegment(fs, 0);
#endif
}
xen_mc_batch();
load_TLS_descriptor(t, cpu, 0);
load_TLS_descriptor(t, cpu, 1);
load_TLS_descriptor(t, cpu, 2);
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
#ifdef CONFIG_X86_64
static void xen_load_gs_index(unsigned int idx)
{
if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
BUG();
}
#endif
static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
const void *ptr)
{
unsigned long lp = (unsigned long)&dt[entrynum];
xmaddr_t mach_lp = virt_to_machine(lp);
u64 entry = *(u64 *)ptr;
preempt_disable();
xen_mc_flush();
if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
BUG();
preempt_enable();
}
static int cvt_gate_to_trap(int vector, const gate_desc *val,
struct trap_info *info)
{
if (val->type != 0xf && val->type != 0xe)
return 0;
info->vector = vector;
info->address = gate_offset(*val);
info->cs = gate_segment(*val);
info->flags = val->dpl;
/* interrupt gates clear IF */
if (val->type == 0xe)
info->flags |= 4;
return 1;
}
/* Locations of each CPU's IDT */
static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
/* Set an IDT entry. If the entry is part of the current IDT, then
also update Xen. */
static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
{
unsigned long p = (unsigned long)&dt[entrynum];
unsigned long start, end;
preempt_disable();
start = __get_cpu_var(idt_desc).address;
end = start + __get_cpu_var(idt_desc).size + 1;
xen_mc_flush();
native_write_idt_entry(dt, entrynum, g);
if (p >= start && (p + 8) <= end) {
struct trap_info info[2];
info[1].address = 0;
if (cvt_gate_to_trap(entrynum, g, &info[0]))
if (HYPERVISOR_set_trap_table(info))
BUG();
}
preempt_enable();
}
static void xen_convert_trap_info(const struct desc_ptr *desc,
struct trap_info *traps)
{
unsigned in, out, count;
count = (desc->size+1) / sizeof(gate_desc);
BUG_ON(count > 256);
for (in = out = 0; in < count; in++) {
gate_desc *entry = (gate_desc*)(desc->address) + in;
if (cvt_gate_to_trap(in, entry, &traps[out]))
out++;
}
traps[out].address = 0;
}
void xen_copy_trap_info(struct trap_info *traps)
{
const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
xen_convert_trap_info(desc, traps);
}
/* Load a new IDT into Xen. In principle this can be per-CPU, so we
hold a spinlock to protect the static traps[] array (static because
it avoids allocation, and saves stack space). */
static void xen_load_idt(const struct desc_ptr *desc)
{
static DEFINE_SPINLOCK(lock);
static struct trap_info traps[257];
spin_lock(&lock);
__get_cpu_var(idt_desc) = *desc;
xen_convert_trap_info(desc, traps);
xen_mc_flush();
if (HYPERVISOR_set_trap_table(traps))
BUG();
spin_unlock(&lock);
}
/* Write a GDT descriptor entry. Ignore LDT descriptors, since
they're handled differently. */
static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
const void *desc, int type)
{
preempt_disable();
switch (type) {
case DESC_LDT:
case DESC_TSS:
/* ignore */
break;
default: {
xmaddr_t maddr = virt_to_machine(&dt[entry]);
xen_mc_flush();
if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
BUG();
}
}
preempt_enable();
}
static void xen_load_sp0(struct tss_struct *tss,
struct thread_struct *thread)
{
struct multicall_space mcs = xen_mc_entry(0);
MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
static void xen_set_iopl_mask(unsigned mask)
{
struct physdev_set_iopl set_iopl;
/* Force the change at ring 0. */
set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
}
static void xen_io_delay(void)
{
}
#ifdef CONFIG_X86_LOCAL_APIC
static u32 xen_apic_read(unsigned long reg)
{
return 0;
}
static void xen_apic_write(unsigned long reg, u32 val)
{
/* Warn to see if there's any stray references */
WARN_ON(1);
}
#endif
static void xen_flush_tlb(void)
{
struct mmuext_op *op;
struct multicall_space mcs;
preempt_disable();
mcs = xen_mc_entry(sizeof(*op));
op = mcs.args;
op->cmd = MMUEXT_TLB_FLUSH_LOCAL;
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
xen_mc_issue(PARAVIRT_LAZY_MMU);
preempt_enable();
}
static void xen_flush_tlb_single(unsigned long addr)
{
struct mmuext_op *op;
struct multicall_space mcs;
preempt_disable();
mcs = xen_mc_entry(sizeof(*op));
op = mcs.args;
op->cmd = MMUEXT_INVLPG_LOCAL;
op->arg1.linear_addr = addr & PAGE_MASK;
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
xen_mc_issue(PARAVIRT_LAZY_MMU);
preempt_enable();
}
static void xen_flush_tlb_others(const cpumask_t *cpus, struct mm_struct *mm,
unsigned long va)
{
struct {
struct mmuext_op op;
cpumask_t mask;
} *args;
cpumask_t cpumask = *cpus;
struct multicall_space mcs;
/*
* A couple of (to be removed) sanity checks:
*
* - current CPU must not be in mask
* - mask must exist :)
*/
BUG_ON(cpus_empty(cpumask));
BUG_ON(cpu_isset(smp_processor_id(), cpumask));
BUG_ON(!mm);
/* If a CPU which we ran on has gone down, OK. */
cpus_and(cpumask, cpumask, cpu_online_map);
if (cpus_empty(cpumask))
return;
mcs = xen_mc_entry(sizeof(*args));
args = mcs.args;
args->mask = cpumask;
args->op.arg2.vcpumask = &args->mask;
if (va == TLB_FLUSH_ALL) {
args->op.cmd = MMUEXT_TLB_FLUSH_MULTI;
} else {
args->op.cmd = MMUEXT_INVLPG_MULTI;
args->op.arg1.linear_addr = va;
}
MULTI_mmuext_op(mcs.mc, &args->op, 1, NULL, DOMID_SELF);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
static void xen_clts(void)
{
struct multicall_space mcs;
mcs = xen_mc_entry(0);
MULTI_fpu_taskswitch(mcs.mc, 0);
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
static void xen_write_cr0(unsigned long cr0)
{
struct multicall_space mcs;
/* Only pay attention to cr0.TS; everything else is
ignored. */
mcs = xen_mc_entry(0);
MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
xen_mc_issue(PARAVIRT_LAZY_CPU);
}
static void xen_write_cr2(unsigned long cr2)
{
x86_read_percpu(xen_vcpu)->arch.cr2 = cr2;
}
static unsigned long xen_read_cr2(void)
{
return x86_read_percpu(xen_vcpu)->arch.cr2;
}
static unsigned long xen_read_cr2_direct(void)
{
return x86_read_percpu(xen_vcpu_info.arch.cr2);
}
static void xen_write_cr4(unsigned long cr4)
{
cr4 &= ~X86_CR4_PGE;
cr4 &= ~X86_CR4_PSE;
native_write_cr4(cr4);
}
static unsigned long xen_read_cr3(void)
{
return x86_read_percpu(xen_cr3);
}
static void set_current_cr3(void *v)
{
x86_write_percpu(xen_current_cr3, (unsigned long)v);
}
static void __xen_write_cr3(bool kernel, unsigned long cr3)
{
struct mmuext_op *op;
struct multicall_space mcs;
unsigned long mfn;
if (cr3)
mfn = pfn_to_mfn(PFN_DOWN(cr3));
else
mfn = 0;
WARN_ON(mfn == 0 && kernel);
mcs = __xen_mc_entry(sizeof(*op));
op = mcs.args;
op->cmd = kernel ? MMUEXT_NEW_BASEPTR : MMUEXT_NEW_USER_BASEPTR;
op->arg1.mfn = mfn;
MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
if (kernel) {
x86_write_percpu(xen_cr3, cr3);
/* Update xen_current_cr3 once the batch has actually
been submitted. */
xen_mc_callback(set_current_cr3, (void *)cr3);
}
}
static void xen_write_cr3(unsigned long cr3)
{
BUG_ON(preemptible());
xen_mc_batch(); /* disables interrupts */
/* Update while interrupts are disabled, so its atomic with
respect to ipis */
x86_write_percpu(xen_cr3, cr3);
__xen_write_cr3(true, cr3);
#ifdef CONFIG_X86_64
{
pgd_t *user_pgd = xen_get_user_pgd(__va(cr3));
if (user_pgd)
__xen_write_cr3(false, __pa(user_pgd));
else
__xen_write_cr3(false, 0);
}
#endif
xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */
}
static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
{
int ret;
ret = 0;
switch(msr) {
#ifdef CONFIG_X86_64
unsigned which;
u64 base;
case MSR_FS_BASE: which = SEGBASE_FS; goto set;
case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set;
case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set;
set:
base = ((u64)high << 32) | low;
if (HYPERVISOR_set_segment_base(which, base) != 0)
ret = -EFAULT;
break;
#endif
default:
ret = native_write_msr_safe(msr, low, high);
}
return ret;
}
/* Early in boot, while setting up the initial pagetable, assume
everything is pinned. */
static __init void xen_alloc_pte_init(struct mm_struct *mm, u32 pfn)
{
#ifdef CONFIG_FLATMEM
BUG_ON(mem_map); /* should only be used early */
#endif
make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
}
/* Early release_pte assumes that all pts are pinned, since there's
only init_mm and anything attached to that is pinned. */
static void xen_release_pte_init(u32 pfn)
{
make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
}
static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
{
struct mmuext_op op;
op.cmd = cmd;
op.arg1.mfn = pfn_to_mfn(pfn);
if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
BUG();
}
/* This needs to make sure the new pte page is pinned iff its being
attached to a pinned pagetable. */
static void xen_alloc_ptpage(struct mm_struct *mm, u32 pfn, unsigned level)
{
struct page *page = pfn_to_page(pfn);
if (PagePinned(virt_to_page(mm->pgd))) {
SetPagePinned(page);
if (!PageHighMem(page)) {
make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
if (level == PT_PTE)
pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn);
} else
/* make sure there are no stray mappings of
this page */
kmap_flush_unused();
}
}
static void xen_alloc_pte(struct mm_struct *mm, u32 pfn)
{
xen_alloc_ptpage(mm, pfn, PT_PTE);
}
static void xen_alloc_pmd(struct mm_struct *mm, u32 pfn)
{
xen_alloc_ptpage(mm, pfn, PT_PMD);
}
static int xen_pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd = mm->pgd;
int ret = 0;
BUG_ON(PagePinned(virt_to_page(pgd)));
#ifdef CONFIG_X86_64
{
struct page *page = virt_to_page(pgd);
pgd_t *user_pgd;
BUG_ON(page->private != 0);
ret = -ENOMEM;
user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
page->private = (unsigned long)user_pgd;
if (user_pgd != NULL) {
user_pgd[pgd_index(VSYSCALL_START)] =
__pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE);
ret = 0;
}
BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd))));
}
#endif
return ret;
}
static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
#ifdef CONFIG_X86_64
pgd_t *user_pgd = xen_get_user_pgd(pgd);
if (user_pgd)
free_page((unsigned long)user_pgd);
#endif
}
/* This should never happen until we're OK to use struct page */
static void xen_release_ptpage(u32 pfn, unsigned level)
{
struct page *page = pfn_to_page(pfn);
if (PagePinned(page)) {
if (!PageHighMem(page)) {
if (level == PT_PTE)
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
}
ClearPagePinned(page);
}
}
static void xen_release_pte(u32 pfn)
{
xen_release_ptpage(pfn, PT_PTE);
}
static void xen_release_pmd(u32 pfn)
{
xen_release_ptpage(pfn, PT_PMD);
}
#if PAGETABLE_LEVELS == 4
static void xen_alloc_pud(struct mm_struct *mm, u32 pfn)
{
xen_alloc_ptpage(mm, pfn, PT_PUD);
}
static void xen_release_pud(u32 pfn)
{
xen_release_ptpage(pfn, PT_PUD);
}
#endif
#ifdef CONFIG_HIGHPTE
static void *xen_kmap_atomic_pte(struct page *page, enum km_type type)
{
pgprot_t prot = PAGE_KERNEL;
if (PagePinned(page))
prot = PAGE_KERNEL_RO;
if (0 && PageHighMem(page))
printk("mapping highpte %lx type %d prot %s\n",
page_to_pfn(page), type,
(unsigned long)pgprot_val(prot) & _PAGE_RW ? "WRITE" : "READ");
return kmap_atomic_prot(page, type, prot);
}
#endif
static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
{
/* If there's an existing pte, then don't allow _PAGE_RW to be set */
if (pte_val_ma(*ptep) & _PAGE_PRESENT)
pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) &
pte_val_ma(pte));
return pte;
}
/* Init-time set_pte while constructing initial pagetables, which
doesn't allow RO pagetable pages to be remapped RW */
static __init void xen_set_pte_init(pte_t *ptep, pte_t pte)
{
pte = mask_rw_pte(ptep, pte);
xen_set_pte(ptep, pte);
}
static __init void xen_pagetable_setup_start(pgd_t *base)
{
}
void xen_setup_shared_info(void)
{
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
set_fixmap(FIX_PARAVIRT_BOOTMAP,
xen_start_info->shared_info);
HYPERVISOR_shared_info =
(struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
} else
HYPERVISOR_shared_info =
(struct shared_info *)__va(xen_start_info->shared_info);
#ifndef CONFIG_SMP
/* In UP this is as good a place as any to set up shared info */
xen_setup_vcpu_info_placement();
#endif
xen_setup_mfn_list_list();
}
static __init void xen_pagetable_setup_done(pgd_t *base)
{
xen_setup_shared_info();
}
static __init void xen_post_allocator_init(void)
{
pv_mmu_ops.set_pte = xen_set_pte;
pv_mmu_ops.set_pmd = xen_set_pmd;
pv_mmu_ops.set_pud = xen_set_pud;
#if PAGETABLE_LEVELS == 4
pv_mmu_ops.set_pgd = xen_set_pgd;
#endif
/* This will work as long as patching hasn't happened yet
(which it hasn't) */
pv_mmu_ops.alloc_pte = xen_alloc_pte;
pv_mmu_ops.alloc_pmd = xen_alloc_pmd;
pv_mmu_ops.release_pte = xen_release_pte;
pv_mmu_ops.release_pmd = xen_release_pmd;
#if PAGETABLE_LEVELS == 4
pv_mmu_ops.alloc_pud = xen_alloc_pud;
pv_mmu_ops.release_pud = xen_release_pud;
#endif
#ifdef CONFIG_X86_64
SetPagePinned(virt_to_page(level3_user_vsyscall));
#endif
xen_mark_init_mm_pinned();
}
/* This is called once we have the cpu_possible_map */
void xen_setup_vcpu_info_placement(void)
{
int cpu;
for_each_possible_cpu(cpu)
xen_vcpu_setup(cpu);
/* xen_vcpu_setup managed to place the vcpu_info within the
percpu area for all cpus, so make use of it */
#ifdef CONFIG_X86_32
if (have_vcpu_info_placement) {
printk(KERN_INFO "Xen: using vcpu_info placement\n");
pv_irq_ops.save_fl = xen_save_fl_direct;
pv_irq_ops.restore_fl = xen_restore_fl_direct;
pv_irq_ops.irq_disable = xen_irq_disable_direct;
pv_irq_ops.irq_enable = xen_irq_enable_direct;
pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
}
#endif
}
static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
unsigned long addr, unsigned len)
{
char *start, *end, *reloc;
unsigned ret;
start = end = reloc = NULL;
#define SITE(op, x) \
case PARAVIRT_PATCH(op.x): \
if (have_vcpu_info_placement) { \
start = (char *)xen_##x##_direct; \
end = xen_##x##_direct_end; \
reloc = xen_##x##_direct_reloc; \
} \
goto patch_site
switch (type) {
#ifdef CONFIG_X86_32
SITE(pv_irq_ops, irq_enable);
SITE(pv_irq_ops, irq_disable);
SITE(pv_irq_ops, save_fl);
SITE(pv_irq_ops, restore_fl);
#endif /* CONFIG_X86_32 */
#undef SITE
patch_site:
if (start == NULL || (end-start) > len)
goto default_patch;
ret = paravirt_patch_insns(insnbuf, len, start, end);
/* Note: because reloc is assigned from something that
appears to be an array, gcc assumes it's non-null,
but doesn't know its relationship with start and
end. */
if (reloc > start && reloc < end) {
int reloc_off = reloc - start;
long *relocp = (long *)(insnbuf + reloc_off);
long delta = start - (char *)addr;
*relocp += delta;
}
break;
default_patch:
default:
ret = paravirt_patch_default(type, clobbers, insnbuf,
addr, len);
break;
}
return ret;
}
static void xen_set_fixmap(unsigned idx, unsigned long phys, pgprot_t prot)
{
pte_t pte;
phys >>= PAGE_SHIFT;
switch (idx) {
case FIX_BTMAP_END ... FIX_BTMAP_BEGIN:
#ifdef CONFIG_X86_F00F_BUG
case FIX_F00F_IDT:
#endif
#ifdef CONFIG_X86_32
case FIX_WP_TEST:
case FIX_VDSO:
# ifdef CONFIG_HIGHMEM
case FIX_KMAP_BEGIN ... FIX_KMAP_END:
# endif
#else
case VSYSCALL_LAST_PAGE ... VSYSCALL_FIRST_PAGE:
#endif
#ifdef CONFIG_X86_LOCAL_APIC
case FIX_APIC_BASE: /* maps dummy local APIC */
#endif
pte = pfn_pte(phys, prot);
break;
default:
pte = mfn_pte(phys, prot);
break;
}
__native_set_fixmap(idx, pte);
#ifdef CONFIG_X86_64
/* Replicate changes to map the vsyscall page into the user
pagetable vsyscall mapping. */
if (idx >= VSYSCALL_LAST_PAGE && idx <= VSYSCALL_FIRST_PAGE) {
unsigned long vaddr = __fix_to_virt(idx);
set_pte_vaddr_pud(level3_user_vsyscall, vaddr, pte);
}
#endif
}
static const struct pv_info xen_info __initdata = {
.paravirt_enabled = 1,
.shared_kernel_pmd = 0,
.name = "Xen",
};
static const struct pv_init_ops xen_init_ops __initdata = {
.patch = xen_patch,
.banner = xen_banner,
.memory_setup = xen_memory_setup,
.arch_setup = xen_arch_setup,
.post_allocator_init = xen_post_allocator_init,
};
static const struct pv_time_ops xen_time_ops __initdata = {
.time_init = xen_time_init,
.set_wallclock = xen_set_wallclock,
.get_wallclock = xen_get_wallclock,
.get_tsc_khz = xen_tsc_khz,
.sched_clock = xen_sched_clock,
};
static const struct pv_cpu_ops xen_cpu_ops __initdata = {
.cpuid = xen_cpuid,
.set_debugreg = xen_set_debugreg,
.get_debugreg = xen_get_debugreg,
.clts = xen_clts,
.read_cr0 = native_read_cr0,
.write_cr0 = xen_write_cr0,
.read_cr4 = native_read_cr4,
.read_cr4_safe = native_read_cr4_safe,
.write_cr4 = xen_write_cr4,
.wbinvd = native_wbinvd,
.read_msr = native_read_msr_safe,
.write_msr = xen_write_msr_safe,
.read_tsc = native_read_tsc,
.read_pmc = native_read_pmc,
.iret = xen_iret,
.irq_enable_sysexit = xen_sysexit,
#ifdef CONFIG_X86_64
.usergs_sysret32 = xen_sysret32,
.usergs_sysret64 = xen_sysret64,
#endif
.load_tr_desc = paravirt_nop,
.set_ldt = xen_set_ldt,
.load_gdt = xen_load_gdt,
.load_idt = xen_load_idt,
.load_tls = xen_load_tls,
#ifdef CONFIG_X86_64
.load_gs_index = xen_load_gs_index,
#endif
.store_gdt = native_store_gdt,
.store_idt = native_store_idt,
.store_tr = xen_store_tr,
.write_ldt_entry = xen_write_ldt_entry,
.write_gdt_entry = xen_write_gdt_entry,
.write_idt_entry = xen_write_idt_entry,
.load_sp0 = xen_load_sp0,
.set_iopl_mask = xen_set_iopl_mask,
.io_delay = xen_io_delay,
/* Xen takes care of %gs when switching to usermode for us */
.swapgs = paravirt_nop,
.lazy_mode = {
.enter = paravirt_enter_lazy_cpu,
.leave = xen_leave_lazy,
},
};
static void __init __xen_init_IRQ(void)
{
#ifdef CONFIG_X86_64
int i;
/* Create identity vector->irq map */
for(i = 0; i < NR_VECTORS; i++) {
int cpu;
for_each_possible_cpu(cpu)
per_cpu(vector_irq, cpu)[i] = i;
}
#endif /* CONFIG_X86_64 */
xen_init_IRQ();
}
static const struct pv_irq_ops xen_irq_ops __initdata = {
.init_IRQ = __xen_init_IRQ,
.save_fl = xen_save_fl,
.restore_fl = xen_restore_fl,
.irq_disable = xen_irq_disable,
.irq_enable = xen_irq_enable,
.safe_halt = xen_safe_halt,
.halt = xen_halt,
#ifdef CONFIG_X86_64
.adjust_exception_frame = xen_adjust_exception_frame,
#endif
};
static const struct pv_apic_ops xen_apic_ops __initdata = {
#ifdef CONFIG_X86_LOCAL_APIC
.apic_write = xen_apic_write,
.apic_read = xen_apic_read,
.setup_boot_clock = paravirt_nop,
.setup_secondary_clock = paravirt_nop,
.startup_ipi_hook = paravirt_nop,
#endif
};
static const struct pv_mmu_ops xen_mmu_ops __initdata = {
.pagetable_setup_start = xen_pagetable_setup_start,
.pagetable_setup_done = xen_pagetable_setup_done,
.read_cr2 = xen_read_cr2,
.write_cr2 = xen_write_cr2,
.read_cr3 = xen_read_cr3,
.write_cr3 = xen_write_cr3,
.flush_tlb_user = xen_flush_tlb,
.flush_tlb_kernel = xen_flush_tlb,
.flush_tlb_single = xen_flush_tlb_single,
.flush_tlb_others = xen_flush_tlb_others,
.pte_update = paravirt_nop,
.pte_update_defer = paravirt_nop,
.pgd_alloc = xen_pgd_alloc,
.pgd_free = xen_pgd_free,
.alloc_pte = xen_alloc_pte_init,
.release_pte = xen_release_pte_init,
.alloc_pmd = xen_alloc_pte_init,
.alloc_pmd_clone = paravirt_nop,
.release_pmd = xen_release_pte_init,
#ifdef CONFIG_HIGHPTE
.kmap_atomic_pte = xen_kmap_atomic_pte,
#endif
#ifdef CONFIG_X86_64
.set_pte = xen_set_pte,
#else
.set_pte = xen_set_pte_init,
#endif
.set_pte_at = xen_set_pte_at,
.set_pmd = xen_set_pmd_hyper,
.ptep_modify_prot_start = __ptep_modify_prot_start,
.ptep_modify_prot_commit = __ptep_modify_prot_commit,
.pte_val = xen_pte_val,
.pte_flags = native_pte_flags,
.pgd_val = xen_pgd_val,
.make_pte = xen_make_pte,
.make_pgd = xen_make_pgd,
#ifdef CONFIG_X86_PAE
.set_pte_atomic = xen_set_pte_atomic,
.set_pte_present = xen_set_pte_at,
.pte_clear = xen_pte_clear,
.pmd_clear = xen_pmd_clear,
#endif /* CONFIG_X86_PAE */
.set_pud = xen_set_pud_hyper,
.make_pmd = xen_make_pmd,
.pmd_val = xen_pmd_val,
#if PAGETABLE_LEVELS == 4
.pud_val = xen_pud_val,
.make_pud = xen_make_pud,
.set_pgd = xen_set_pgd_hyper,
.alloc_pud = xen_alloc_pte_init,
.release_pud = xen_release_pte_init,
#endif /* PAGETABLE_LEVELS == 4 */
.activate_mm = xen_activate_mm,
.dup_mmap = xen_dup_mmap,
.exit_mmap = xen_exit_mmap,
.lazy_mode = {
.enter = paravirt_enter_lazy_mmu,
.leave = xen_leave_lazy,
},
.set_fixmap = xen_set_fixmap,
};
static void xen_reboot(int reason)
{
struct sched_shutdown r = { .reason = reason };
#ifdef CONFIG_SMP
smp_send_stop();
#endif
if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
BUG();
}
static void xen_restart(char *msg)
{
xen_reboot(SHUTDOWN_reboot);
}
static void xen_emergency_restart(void)
{
xen_reboot(SHUTDOWN_reboot);
}
static void xen_machine_halt(void)
{
xen_reboot(SHUTDOWN_poweroff);
}
static void xen_crash_shutdown(struct pt_regs *regs)
{
xen_reboot(SHUTDOWN_crash);
}
static const struct machine_ops __initdata xen_machine_ops = {
.restart = xen_restart,
.halt = xen_machine_halt,
.power_off = xen_machine_halt,
.shutdown = xen_machine_halt,
.crash_shutdown = xen_crash_shutdown,
.emergency_restart = xen_emergency_restart,
};
static void __init xen_reserve_top(void)
{
#ifdef CONFIG_X86_32
unsigned long top = HYPERVISOR_VIRT_START;
struct xen_platform_parameters pp;
if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0)
top = pp.virt_start;
reserve_top_address(-top + 2 * PAGE_SIZE);
#endif /* CONFIG_X86_32 */
}
/*
* Like __va(), but returns address in the kernel mapping (which is
* all we have until the physical memory mapping has been set up.
*/
static void *__ka(phys_addr_t paddr)
{
#ifdef CONFIG_X86_64
return (void *)(paddr + __START_KERNEL_map);
#else
return __va(paddr);
#endif
}
/* Convert a machine address to physical address */
static unsigned long m2p(phys_addr_t maddr)
{
phys_addr_t paddr;
maddr &= PTE_PFN_MASK;
paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT;
return paddr;
}
/* Convert a machine address to kernel virtual */
static void *m2v(phys_addr_t maddr)
{
return __ka(m2p(maddr));
}
#ifdef CONFIG_X86_64
static void walk(pgd_t *pgd, unsigned long addr)
{
unsigned l4idx = pgd_index(addr);
unsigned l3idx = pud_index(addr);
unsigned l2idx = pmd_index(addr);
unsigned l1idx = pte_index(addr);
pgd_t l4;
pud_t l3;
pmd_t l2;
pte_t l1;
xen_raw_printk("walk %p, %lx -> %d %d %d %d\n",
pgd, addr, l4idx, l3idx, l2idx, l1idx);
l4 = pgd[l4idx];
xen_raw_printk(" l4: %016lx\n", l4.pgd);
xen_raw_printk(" %016lx\n", pgd_val(l4));
l3 = ((pud_t *)(m2v(l4.pgd)))[l3idx];
xen_raw_printk(" l3: %016lx\n", l3.pud);
xen_raw_printk(" %016lx\n", pud_val(l3));
l2 = ((pmd_t *)(m2v(l3.pud)))[l2idx];
xen_raw_printk(" l2: %016lx\n", l2.pmd);
xen_raw_printk(" %016lx\n", pmd_val(l2));
l1 = ((pte_t *)(m2v(l2.pmd)))[l1idx];
xen_raw_printk(" l1: %016lx\n", l1.pte);
xen_raw_printk(" %016lx\n", pte_val(l1));
}
#endif
static void set_page_prot(void *addr, pgprot_t prot)
{
unsigned long pfn = __pa(addr) >> PAGE_SHIFT;
pte_t pte = pfn_pte(pfn, prot);
xen_raw_printk("addr=%p pfn=%lx mfn=%lx prot=%016llx pte=%016llx\n",
addr, pfn, get_phys_to_machine(pfn),
pgprot_val(prot), pte.pte);
if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0))
BUG();
}
static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
{
unsigned pmdidx, pteidx;
unsigned ident_pte;
unsigned long pfn;
ident_pte = 0;
pfn = 0;
for(pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) {
pte_t *pte_page;
/* Reuse or allocate a page of ptes */
if (pmd_present(pmd[pmdidx]))
pte_page = m2v(pmd[pmdidx].pmd);
else {
/* Check for free pte pages */
if (ident_pte == ARRAY_SIZE(level1_ident_pgt))
break;
pte_page = &level1_ident_pgt[ident_pte];
ident_pte += PTRS_PER_PTE;
pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE);
}
/* Install mappings */
for(pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
pte_t pte;
if (pfn > max_pfn_mapped)
max_pfn_mapped = pfn;
if (!pte_none(pte_page[pteidx]))
continue;
pte = pfn_pte(pfn, PAGE_KERNEL_EXEC);
pte_page[pteidx] = pte;
}
}
for(pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE)
set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO);
set_page_prot(pmd, PAGE_KERNEL_RO);
}
#ifdef CONFIG_X86_64
static void convert_pfn_mfn(void *v)
{
pte_t *pte = v;
int i;
/* All levels are converted the same way, so just treat them
as ptes. */
for(i = 0; i < PTRS_PER_PTE; i++)
pte[i] = xen_make_pte(pte[i].pte);
}
/*
* Set up the inital kernel pagetable.
*
* We can construct this by grafting the Xen provided pagetable into
* head_64.S's preconstructed pagetables. We copy the Xen L2's into
* level2_ident_pgt, level2_kernel_pgt and level2_fixmap_pgt. This
* means that only the kernel has a physical mapping to start with -
* but that's enough to get __va working. We need to fill in the rest
* of the physical mapping once some sort of allocator has been set
* up.
*/
static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
{
pud_t *l3;
pmd_t *l2;
/* Zap identity mapping */
init_level4_pgt[0] = __pgd(0);
/* Pre-constructed entries are in pfn, so convert to mfn */
convert_pfn_mfn(init_level4_pgt);
convert_pfn_mfn(level3_ident_pgt);
convert_pfn_mfn(level3_kernel_pgt);
l3 = m2v(pgd[pgd_index(__START_KERNEL_map)].pgd);
l2 = m2v(l3[pud_index(__START_KERNEL_map)].pud);
memcpy(level2_ident_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
memcpy(level2_kernel_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
l3 = m2v(pgd[pgd_index(__START_KERNEL_map + PMD_SIZE)].pgd);
l2 = m2v(l3[pud_index(__START_KERNEL_map + PMD_SIZE)].pud);
memcpy(level2_fixmap_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
/* Set up identity map */
xen_map_identity_early(level2_ident_pgt, max_pfn);
/* Make pagetable pieces RO */
set_page_prot(init_level4_pgt, PAGE_KERNEL_RO);
set_page_prot(level3_ident_pgt, PAGE_KERNEL_RO);
set_page_prot(level3_kernel_pgt, PAGE_KERNEL_RO);
set_page_prot(level3_user_vsyscall, PAGE_KERNEL_RO);
set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
set_page_prot(level2_fixmap_pgt, PAGE_KERNEL_RO);
/* Pin down new L4 */
pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE,
PFN_DOWN(__pa_symbol(init_level4_pgt)));
/* Unpin Xen-provided one */
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
/* Switch over */
pgd = init_level4_pgt;
/*
* At this stage there can be no user pgd, and no page
* structure to attach it to, so make sure we just set kernel
* pgd.
*/
xen_mc_batch();
__xen_write_cr3(true, __pa(pgd));
xen_mc_issue(PARAVIRT_LAZY_CPU);
reserve_early(__pa(xen_start_info->pt_base),
__pa(xen_start_info->pt_base +
xen_start_info->nr_pt_frames * PAGE_SIZE),
"XEN PAGETABLES");
return pgd;
}
#else /* !CONFIG_X86_64 */
static pmd_t level2_kernel_pgt[PTRS_PER_PMD] __page_aligned_bss;
static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
{
pmd_t *kernel_pmd;
init_pg_tables_start = __pa(pgd);
init_pg_tables_end = __pa(pgd) + xen_start_info->nr_pt_frames*PAGE_SIZE;
max_pfn_mapped = PFN_DOWN(init_pg_tables_end + 512*1024);
kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);
xen_map_identity_early(level2_kernel_pgt, max_pfn);
memcpy(swapper_pg_dir, pgd, sizeof(pgd_t) * PTRS_PER_PGD);
set_pgd(&swapper_pg_dir[KERNEL_PGD_BOUNDARY],
__pgd(__pa(level2_kernel_pgt) | _PAGE_PRESENT));
set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO);
set_page_prot(empty_zero_page, PAGE_KERNEL_RO);
pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
xen_write_cr3(__pa(swapper_pg_dir));
pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(swapper_pg_dir)));
return swapper_pg_dir;
}
#endif /* CONFIG_X86_64 */
/* First C function to be called on Xen boot */
asmlinkage void __init xen_start_kernel(void)
{
pgd_t *pgd;
if (!xen_start_info)
return;
BUG_ON(memcmp(xen_start_info->magic, "xen-3", 5) != 0);
xen_setup_features();
/* Install Xen paravirt ops */
pv_info = xen_info;
pv_init_ops = xen_init_ops;
pv_time_ops = xen_time_ops;
pv_cpu_ops = xen_cpu_ops;
pv_irq_ops = xen_irq_ops;
pv_apic_ops = xen_apic_ops;
pv_mmu_ops = xen_mmu_ops;
if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
}
machine_ops = xen_machine_ops;
#ifdef CONFIG_X86_64
/* Disable until direct per-cpu data access. */
have_vcpu_info_placement = 0;
x86_64_init_pda();
#endif
xen_smp_init();
/* Get mfn list */
if (!xen_feature(XENFEAT_auto_translated_physmap))
xen_build_dynamic_phys_to_machine();
pgd = (pgd_t *)xen_start_info->pt_base;
/* Prevent unwanted bits from being set in PTEs. */
__supported_pte_mask &= ~_PAGE_GLOBAL;
if (!is_initial_xendomain())
__supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
/* Don't do the full vcpu_info placement stuff until we have a
possible map and a non-dummy shared_info. */
per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
xen_raw_console_write("mapping kernel into physical memory\n");
pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
init_mm.pgd = pgd;
/* keep using Xen gdt for now; no urgent need to change it */
pv_info.kernel_rpl = 1;
if (xen_feature(XENFEAT_supervisor_mode_kernel))
pv_info.kernel_rpl = 0;
/* set the limit of our address space */
xen_reserve_top();
#ifdef CONFIG_X86_32
/* set up basic CPUID stuff */
cpu_detect(&new_cpu_data);
new_cpu_data.hard_math = 1;
new_cpu_data.x86_capability[0] = cpuid_edx(1);
#endif
/* Poke various useful things into boot_params */
boot_params.hdr.type_of_loader = (9 << 4) | 0;
boot_params.hdr.ramdisk_image = xen_start_info->mod_start
? __pa(xen_start_info->mod_start) : 0;
boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
if (!is_initial_xendomain()) {
add_preferred_console("xenboot", 0, NULL);
add_preferred_console("tty", 0, NULL);
add_preferred_console("hvc", 0, NULL);
}
xen_raw_console_write("about to get started...\n");
#if 0
xen_raw_printk("&boot_params=%p __pa(&boot_params)=%lx __va(__pa(&boot_params))=%lx\n",
&boot_params, __pa_symbol(&boot_params),
__va(__pa_symbol(&boot_params)));
walk(pgd, &boot_params);
walk(pgd, __va(__pa(&boot_params)));
#endif
/* Start the world */
#ifdef CONFIG_X86_32
i386_start_kernel();
#else
x86_64_start_reservations((char *)__pa_symbol(&boot_params));
#endif
}
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