/* Paravirtualization interfaces
Copyright (C) 2006 Rusty Russell IBM Corporation
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/efi.h>
#include <linux/bcd.h>
#include <linux/start_kernel.h>
#include <asm/bug.h>
#include <asm/paravirt.h>
#include <asm/desc.h>
#include <asm/setup.h>
#include <asm/arch_hooks.h>
#include <asm/time.h>
#include <asm/irq.h>
#include <asm/delay.h>
#include <asm/fixmap.h>
#include <asm/apic.h>
#include <asm/tlbflush.h>
/* nop stub */
static void native_nop(void)
{
}
static void __init default_banner(void)
{
printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
paravirt_ops.name);
}
char *memory_setup(void)
{
return paravirt_ops.memory_setup();
}
/* Simple instruction patching code. */
#define DEF_NATIVE(name, code) \
extern const char start_##name[], end_##name[]; \
asm("start_" #name ": " code "; end_" #name ":")
DEF_NATIVE(cli, "cli");
DEF_NATIVE(sti, "sti");
DEF_NATIVE(popf, "push %eax; popf");
DEF_NATIVE(pushf, "pushf; pop %eax");
DEF_NATIVE(pushf_cli, "pushf; pop %eax; cli");
DEF_NATIVE(iret, "iret");
DEF_NATIVE(sti_sysexit, "sti; sysexit");
static const struct native_insns
{
const char *start, *end;
} native_insns[] = {
[PARAVIRT_IRQ_DISABLE] = { start_cli, end_cli },
[PARAVIRT_IRQ_ENABLE] = { start_sti, end_sti },
[PARAVIRT_RESTORE_FLAGS] = { start_popf, end_popf },
[PARAVIRT_SAVE_FLAGS] = { start_pushf, end_pushf },
[PARAVIRT_SAVE_FLAGS_IRQ_DISABLE] = { start_pushf_cli, end_pushf_cli },
[PARAVIRT_INTERRUPT_RETURN] = { start_iret, end_iret },
[PARAVIRT_STI_SYSEXIT] = { start_sti_sysexit, end_sti_sysexit },
};
static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len)
{
unsigned int insn_len;
/* Don't touch it if we don't have a replacement */
if (type >= ARRAY_SIZE(native_insns) || !native_insns[type].start)
return len;
insn_len = native_insns[type].end - native_insns[type].start;
/* Similarly if we can't fit replacement. */
if (len < insn_len)
return len;
memcpy(insns, native_insns[type].start, insn_len);
return insn_len;
}
static fastcall unsigned long native_get_debugreg(int regno)
{
unsigned long val = 0; /* Damn you, gcc! */
switch (regno) {
case 0:
asm("movl %%db0, %0" :"=r" (val)); break;
case 1:
asm("movl %%db1, %0" :"=r" (val)); break;
case 2:
asm("movl %%db2, %0" :"=r" (val)); break;
case 3:
asm("movl %%db3, %0" :"=r" (val)); break;
case 6:
asm("movl %%db6, %0" :"=r" (val)); break;
case 7:
asm("movl %%db7, %0" :"=r" (val)); break;
default:
BUG();
}
return val;
}
static fastcall void native_set_debugreg(int regno, unsigned long value)
{
switch (regno) {
case 0:
asm("movl %0,%%db0" : /* no output */ :"r" (value));
break;
case 1:
asm("movl %0,%%db1" : /* no output */ :"r" (value));
break;
case 2:
asm("movl %0,%%db2" : /* no output */ :"r" (value));
break;
case 3:
asm("movl %0,%%db3" : /* no output */ :"r" (value));
break;
case 6:
asm("movl %0,%%db6" : /* no output */ :"r" (value));
break;
case 7:
asm("movl %0,%%db7" : /* no output */ :"r" (value));
break;
default:
BUG();
}
}
void init_IRQ(void)
{
paravirt_ops.init_IRQ();
}
static fastcall void native_clts(void)
{
asm volatile ("clts");
}
static fastcall unsigned long native_read_cr0(void)
{
unsigned long val;
asm volatile("movl %%cr0,%0\n\t" :"=r" (val));
return val;
}
static fastcall void native_write_cr0(unsigned long val)
{
asm volatile("movl %0,%%cr0": :"r" (val));
}
static fastcall unsigned long native_read_cr2(void)
{
unsigned long val;
asm volatile("movl %%cr2,%0\n\t" :"=r" (val));
return val;
}
static fastcall void native_write_cr2(unsigned long val)
{
asm volatile("movl %0,%%cr2": :"r" (val));
}
static fastcall unsigned long native_read_cr3(void)
{
unsigned long val;
asm volatile("movl %%cr3,%0\n\t" :"=r" (val));
return val;
}
static fastcall void native_write_cr3(unsigned long val)
{
asm volatile("movl %0,%%cr3": :"r" (val));
}
static fastcall unsigned long native_read_cr4(void)
{
unsigned long val;
asm volatile("movl %%cr4,%0\n\t" :"=r" (val));
return val;
}
static fastcall unsigned long native_read_cr4_safe(void)
{
unsigned long val;
/* This could fault if %cr4 does not exist */
asm("1: movl %%cr4, %0 \n"
"2: \n"
".section __ex_table,\"a\" \n"
".long 1b,2b \n"
".previous \n"
: "=r" (val): "0" (0));
return val;
}
static fastcall void native_write_cr4(unsigned long val)
{
asm volatile("movl %0,%%cr4": :"r" (val));
}
static fastcall unsigned long native_save_fl(void)
{
unsigned long f;
asm volatile("pushfl ; popl %0":"=g" (f): /* no input */);
return f;
}
static fastcall void native_restore_fl(unsigned long f)
{
asm volatile("pushl %0 ; popfl": /* no output */
:"g" (f)
:"memory", "cc");
}
static fastcall void native_irq_disable(void)
{
asm volatile("cli": : :"memory");
}
static fastcall void native_irq_enable(void)
{
asm volatile("sti": : :"memory");
}
static fastcall void native_safe_halt(void)
{
asm volatile("sti; hlt": : :"memory");
}
static fastcall void native_halt(void)
{
asm volatile("hlt": : :"memory");
}
static fastcall void native_wbinvd(void)
{
asm volatile("wbinvd": : :"memory");
}
static fastcall unsigned long long native_read_msr(unsigned int msr, int *err)
{
unsigned long long val;
asm volatile("2: rdmsr ; xorl %0,%0\n"
"1:\n\t"
".section .fixup,\"ax\"\n\t"
"3: movl %3,%0 ; jmp 1b\n\t"
".previous\n\t"
".section __ex_table,\"a\"\n"
" .align 4\n\t"
" .long 2b,3b\n\t"
".previous"
: "=r" (*err), "=A" (val)
: "c" (msr), "i" (-EFAULT));
return val;
}
static fastcall int native_write_msr(unsigned int msr, unsigned long long val)
{
int err;
asm volatile("2: wrmsr ; xorl %0,%0\n"
"1:\n\t"
".section .fixup,\"ax\"\n\t"
"3: movl %4,%0 ; jmp 1b\n\t"
".previous\n\t"
".section __ex_table,\"a\"\n"
" .align 4\n\t"
" .long 2b,3b\n\t"
".previous"
: "=a" (err)
: "c" (msr), "0" ((u32)val), "d" ((u32)(val>>32)),
"i" (-EFAULT));
return err;
}
static fastcall unsigned long long native_read_tsc(void)
{
unsigned long long val;
asm volatile("rdtsc" : "=A" (val));
return val;
}
static fastcall unsigned long long native_read_pmc(void)
{
unsigned long long val;
asm volatile("rdpmc" : "=A" (val));
return val;
}
static fastcall void native_load_tr_desc(void)
{
asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8));
}
static fastcall void native_load_gdt(const struct Xgt_desc_struct *dtr)
{
asm volatile("lgdt %0"::"m" (*dtr));
}
static fastcall void native_load_idt(const struct Xgt_desc_struct *dtr)
{
asm volatile("lidt %0"::"m" (*dtr));
}
static fastcall void native_store_gdt(struct Xgt_desc_struct *dtr)
{
asm ("sgdt %0":"=m" (*dtr));
}
static fastcall void native_store_idt(struct Xgt_desc_struct *dtr)
{
asm ("sidt %0":"=m" (*dtr));
}
static fastcall unsigned long native_store_tr(void)
{
unsigned long tr;
asm ("str %0":"=r" (tr));
return tr;
}
static fastcall void native_load_tls(struct thread_struct *t, unsigned int cpu)
{
#define C(i) get_cpu_gdt_table(cpu)[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i]
C(0); C(1); C(2);
#undef C
}
static inline void native_write_dt_entry(void *dt, int entry, u32 entry_low, u32 entry_high)
{
u32 *lp = (u32 *)((char *)dt + entry*8);
lp[0] = entry_low;
lp[1] = entry_high;
}
static fastcall void native_write_ldt_entry(void *dt, int entrynum, u32 low, u32 high)
{
native_write_dt_entry(dt, entrynum, low, high);
}
static fastcall void native_write_gdt_entry(void *dt, int entrynum, u32 low, u32 high)
{
native_write_dt_entry(dt, entrynum, low, high);
}
static fastcall void native_write_idt_entry(void *dt, int entrynum, u32 low, u32 high)
{
native_write_dt_entry(dt, entrynum, low, high);
}
static fastcall void native_load_esp0(struct tss_struct *tss,
struct thread_struct *thread)
{
tss->esp0 = thread->esp0;
/* This can only happen when SEP is enabled, no need to test "SEP"arately */
if (unlikely(tss->ss1 != thread->sysenter_cs)) {
tss->ss1 = thread->sysenter_cs;
wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
}
}
static fastcall void native_io_delay(void)
{
asm volatile("outb %al,$0x80");
}
static fastcall void native_flush_tlb(void)
{
__native_flush_tlb();
}
/*
* Global pages have to be flushed a bit differently. Not a real
* performance problem because this does not happen often.
*/
static fastcall void native_flush_tlb_global(void)
{
__native_flush_tlb_global();
}
static fastcall void native_flush_tlb_single(u32 addr)
{
__native_flush_tlb_single(addr);
}
#ifndef CONFIG_X86_PAE
static fastcall void native_set_pte(pte_t *ptep, pte_t pteval)
{
*ptep = pteval;
}
static fastcall void native_set_pte_at(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pteval)
{
*ptep = pteval;
}
static fastcall void native_set_pmd(pmd_t *pmdp, pmd_t pmdval)
{
*pmdp = pmdval;
}
#else /* CONFIG_X86_PAE */
static fastcall void native_set_pte(pte_t *ptep, pte_t pte)
{
ptep->pte_high = pte.pte_high;
smp_wmb();
ptep->pte_low = pte.pte_low;
}
static fastcall void native_set_pte_at(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pte)
{
ptep->pte_high = pte.pte_high;
smp_wmb();
ptep->pte_low = pte.pte_low;
}
static fastcall void native_set_pte_present(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte)
{
ptep->pte_low = 0;
smp_wmb();
ptep->pte_high = pte.pte_high;
smp_wmb();
ptep->pte_low = pte.pte_low;
}
static fastcall void native_set_pte_atomic(pte_t *ptep, pte_t pteval)
{
set_64bit((unsigned long long *)ptep,pte_val(pteval));
}
static fastcall void native_set_pmd(pmd_t *pmdp, pmd_t pmdval)
{
set_64bit((unsigned long long *)pmdp,pmd_val(pmdval));
}
static fastcall void native_set_pud(pud_t *pudp, pud_t pudval)
{
*pudp = pudval;
}
static fastcall void native_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
ptep->pte_low = 0;
smp_wmb();
ptep->pte_high = 0;
}
static fastcall void native_pmd_clear(pmd_t *pmd)
{
u32 *tmp = (u32 *)pmd;
*tmp = 0;
smp_wmb();
*(tmp + 1) = 0;
}
#endif /* CONFIG_X86_PAE */
/* These are in entry.S */
extern fastcall void native_iret(void);
extern fastcall void native_irq_enable_sysexit(void);
static int __init print_banner(void)
{
paravirt_ops.banner();
return 0;
}
core_initcall(print_banner);
/* We simply declare start_kernel to be the paravirt probe of last resort. */
paravirt_probe(start_kernel);
struct paravirt_ops paravirt_ops = {
.name = "bare hardware",
.paravirt_enabled = 0,
.kernel_rpl = 0,
.patch = native_patch,
.banner = default_banner,
.arch_setup = native_nop,
.memory_setup = machine_specific_memory_setup,
.get_wallclock = native_get_wallclock,
.set_wallclock = native_set_wallclock,
.time_init = time_init_hook,
.init_IRQ = native_init_IRQ,
.cpuid = native_cpuid,
.get_debugreg = native_get_debugreg,
.set_debugreg = native_set_debugreg,
.clts = native_clts,
.read_cr0 = native_read_cr0,
.write_cr0 = native_write_cr0,
.read_cr2 = native_read_cr2,
.write_cr2 = native_write_cr2,
.read_cr3 = native_read_cr3,
.write_cr3 = native_write_cr3,
.read_cr4 = native_read_cr4,
.read_cr4_safe = native_read_cr4_safe,
.write_cr4 = native_write_cr4,
.save_fl = native_save_fl,
.restore_fl = native_restore_fl,
.irq_disable = native_irq_disable,
.irq_enable = native_irq_enable,
.safe_halt = native_safe_halt,
.halt = native_halt,
.wbinvd = native_wbinvd,
.read_msr = native_read_msr,
.write_msr = native_write_msr,
.read_tsc = native_read_tsc,
.read_pmc = native_read_pmc,
.load_tr_desc = native_load_tr_desc,
.set_ldt = native_set_ldt,
.load_gdt = native_load_gdt,
.load_idt = native_load_idt,
.store_gdt = native_store_gdt,
.store_idt = native_store_idt,
.store_tr = native_store_tr,
.load_tls = native_load_tls,
.write_ldt_entry = native_write_ldt_entry,
.write_gdt_entry = native_write_gdt_entry,
.write_idt_entry = native_write_idt_entry,
.load_esp0 = native_load_esp0,
.set_iopl_mask = native_set_iopl_mask,
.io_delay = native_io_delay,
.const_udelay = __const_udelay,
#ifdef CONFIG_X86_LOCAL_APIC
.apic_write = native_apic_write,
.apic_write_atomic = native_apic_write_atomic,
.apic_read = native_apic_read,
.setup_boot_clock = setup_boot_APIC_clock,
.setup_secondary_clock = setup_secondary_APIC_clock,
#endif
.set_lazy_mode = (void *)native_nop,
.flush_tlb_user = native_flush_tlb,
.flush_tlb_kernel = native_flush_tlb_global,
.flush_tlb_single = native_flush_tlb_single,
.alloc_pt = (void *)native_nop,
.alloc_pd = (void *)native_nop,
.alloc_pd_clone = (void *)native_nop,
.release_pt = (void *)native_nop,
.release_pd = (void *)native_nop,
.set_pte = native_set_pte,
.set_pte_at = native_set_pte_at,
.set_pmd = native_set_pmd,
.pte_update = (void *)native_nop,
.pte_update_defer = (void *)native_nop,
#ifdef CONFIG_X86_PAE
.set_pte_atomic = native_set_pte_atomic,
.set_pte_present = native_set_pte_present,
.set_pud = native_set_pud,
.pte_clear = native_pte_clear,
.pmd_clear = native_pmd_clear,
#endif
.irq_enable_sysexit = native_irq_enable_sysexit,
.iret = native_iret,
.startup_ipi_hook = (void *)native_nop,
};
/*
* NOTE: CONFIG_PARAVIRT is experimental and the paravirt_ops
* semantics are subject to change. Hence we only do this
* internal-only export of this, until it gets sorted out and
* all lowlevel CPU ops used by modules are separately exported.
*/
EXPORT_SYMBOL_GPL(paravirt_ops);
