arch/i386/kernel/paravirt.c - arm/linux-arm64-legacy - Git at Google

 /*  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>
 #include <asm/timer.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;
 }

 void init_IRQ(void)
 {
 	paravirt_ops.init_IRQ();
 }

 static 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 void native_flush_tlb_global(void)
 {
 	__native_flush_tlb_global();
 }

 static void native_flush_tlb_single(u32 addr)
 {
 	__native_flush_tlb_single(addr);
 }

 #ifndef CONFIG_X86_PAE
 static void native_set_pte(pte_t *ptep, pte_t pteval)
 {
 	*ptep = pteval;
 }

 static void native_set_pte_at(struct mm_struct *mm, u32 addr, pte_t *ptep, pte_t pteval)
 {
 	*ptep = pteval;
 }

 static void native_set_pmd(pmd_t *pmdp, pmd_t pmdval)
 {
 	*pmdp = pmdval;
 }

 #else /* CONFIG_X86_PAE */

 static 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 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 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 void native_set_pte_atomic(pte_t *ptep, pte_t pteval)
 {
 	set_64bit((unsigned long long *)ptep,pte_val(pteval));
 }

 static void native_set_pmd(pmd_t *pmdp, pmd_t pmdval)
 {
 	set_64bit((unsigned long long *)pmdp,pmd_val(pmdval));
 }

 static void native_set_pud(pud_t *pudp, pud_t pudval)
 {
 	*pudp = pudval;
 }

 static 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 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 void native_iret(void);
 extern void native_irq_enable_sysexit(void);

 static int __init print_banner(void)
 {
 	paravirt_ops.banner();
 	return 0;
 }
 core_initcall(print_banner);

 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 = hpet_time_init,
 	.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_safe,
 	.write_msr = native_write_msr_safe,
 	.read_tsc = native_read_tsc,
 	.read_pmc = native_read_pmc,
 	.get_scheduled_cycles = native_read_tsc,
 	.get_cpu_khz = native_calculate_cpu_khz,
 	.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 = write_dt_entry,
 	.write_gdt_entry = write_dt_entry,
 	.write_idt_entry = write_dt_entry,
 	.load_esp0 = native_load_esp0,

 	.set_iopl_mask = native_set_iopl_mask,
 	.io_delay = native_io_delay,

 #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,

 	.map_pt_hook = (void *)native_nop,

 	.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);
	/* 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>
	#include <asm/timer.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;
	}

	void init_IRQ(void)
	{
	paravirt_ops.init_IRQ();
	}

	static 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 void native_flush_tlb_global(void)
	{
	__native_flush_tlb_global();
	}

	static void native_flush_tlb_single(u32 addr)
	{
	__native_flush_tlb_single(addr);
	}

	#ifndef CONFIG_X86_PAE
	static void native_set_pte(pte_t *ptep, pte_t pteval)
	{
	*ptep = pteval;
	}

	static void native_set_pte_at(struct mm_struct mm, u32 addr, pte_t ptep, pte_t pteval)
	{
	*ptep = pteval;
	}

	static void native_set_pmd(pmd_t *pmdp, pmd_t pmdval)
	{
	*pmdp = pmdval;
	}

	#else /* CONFIG_X86_PAE */

	static 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 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 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 void native_set_pte_atomic(pte_t *ptep, pte_t pteval)
	{
	set_64bit((unsigned long long *)ptep,pte_val(pteval));
	}

	static void native_set_pmd(pmd_t *pmdp, pmd_t pmdval)
	{
	set_64bit((unsigned long long *)pmdp,pmd_val(pmdval));
	}

	static void native_set_pud(pud_t *pudp, pud_t pudval)
	{
	*pudp = pudval;
	}

	static 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 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 void native_iret(void);
	extern void native_irq_enable_sysexit(void);

	static int __init print_banner(void)
	{
	paravirt_ops.banner();
	return 0;
	}
	core_initcall(print_banner);

	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 = hpet_time_init,
	.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_safe,
	.write_msr = native_write_msr_safe,
	.read_tsc = native_read_tsc,
	.read_pmc = native_read_pmc,
	.get_scheduled_cycles = native_read_tsc,
	.get_cpu_khz = native_calculate_cpu_khz,
	.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 = write_dt_entry,
	.write_gdt_entry = write_dt_entry,
	.write_idt_entry = write_dt_entry,
	.load_esp0 = native_load_esp0,

	.set_iopl_mask = native_set_iopl_mask,
	.io_delay = native_io_delay,

	#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,

	.map_pt_hook = (void *)native_nop,

	.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);