path: root/include/asm-i386/paravirt.h

#ifndef __ASM_PARAVIRT_H
#define __ASM_PARAVIRT_H
/* Various instructions on x86 need to be replaced for
 * para-virtualization: those hooks are defined here. */

#ifdef CONFIG_PARAVIRT
#include <asm/page.h>

/* Bitmask of what can be clobbered: usually at least eax. */
#define CLBR_NONE 0x0
#define CLBR_EAX 0x1
#define CLBR_ECX 0x2
#define CLBR_EDX 0x4
#define CLBR_ANY 0x7

#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/cpumask.h>
#include <asm/kmap_types.h>

struct page;
struct thread_struct;
struct Xgt_desc_struct;
struct tss_struct;
struct mm_struct;
struct desc_struct;

/* Lazy mode for batching updates / context switch */
enum paravirt_lazy_mode {
	PARAVIRT_LAZY_NONE = 0,
	PARAVIRT_LAZY_MMU = 1,
	PARAVIRT_LAZY_CPU = 2,
	PARAVIRT_LAZY_FLUSH = 3,
};

struct paravirt_ops
{
	unsigned int kernel_rpl;
	int shared_kernel_pmd;
 	int paravirt_enabled;
	const char *name;

	/*
	 * Patch may replace one of the defined code sequences with arbitrary
	 * code, subject to the same register constraints.  This generally
	 * means the code is not free to clobber any registers other than EAX.
	 * The patch function should return the number of bytes of code
	 * generated, as we nop pad the rest in generic code.
	 */
	unsigned (*patch)(u8 type, u16 clobber, void *firstinsn, unsigned len);

	/* Basic arch-specific setup */
	void (*arch_setup)(void);
	char *(*memory_setup)(void);
	void (*post_allocator_init)(void);

	void (*init_IRQ)(void);
	void (*time_init)(void);

	/*
	 * Called before/after init_mm pagetable setup. setup_start
	 * may reset %cr3, and may pre-install parts of the pagetable;
	 * pagetable setup is expected to preserve any existing
	 * mapping.
	 */
	void (*pagetable_setup_start)(pgd_t *pgd_base);
	void (*pagetable_setup_done)(pgd_t *pgd_base);

	/* Print a banner to identify the environment */
	void (*banner)(void);

	/* Set and set time of day */
	unsigned long (*get_wallclock)(void);
	int (*set_wallclock)(unsigned long);

	/* cpuid emulation, mostly so that caps bits can be disabled */
	void (*cpuid)(unsigned int *eax, unsigned int *ebx,
		      unsigned int *ecx, unsigned int *edx);

	/* hooks for various privileged instructions */
	unsigned long (*get_debugreg)(int regno);
	void (*set_debugreg)(int regno, unsigned long value);

	void (*clts)(void);

	unsigned long (*read_cr0)(void);
	void (*write_cr0)(unsigned long);

	unsigned long (*read_cr2)(void);
	void (*write_cr2)(unsigned long);

	unsigned long (*read_cr3)(void);
	void (*write_cr3)(unsigned long);

	unsigned long (*read_cr4_safe)(void);
	unsigned long (*read_cr4)(void);
	void (*write_cr4)(unsigned long);

	/*
	 * Get/set interrupt state.  save_fl and restore_fl are only
	 * expected to use X86_EFLAGS_IF; all other bits
	 * returned from save_fl are undefined, and may be ignored by
	 * restore_fl.
	 */
	unsigned long (*save_fl)(void);
	void (*restore_fl)(unsigned long);
	void (*irq_disable)(void);
	void (*irq_enable)(void);
	void (*safe_halt)(void);
	void (*halt)(void);

	void (*wbinvd)(void);

	/* MSR, PMC and TSR operations.
	   err = 0/-EFAULT.  wrmsr returns 0/-EFAULT. */
	u64 (*read_msr)(unsigned int msr, int *err);
	int (*write_msr)(unsigned int msr, u64 val);

	u64 (*read_tsc)(void);
	u64 (*read_pmc)(void);
 	u64 (*get_scheduled_cycles)(void);
	unsigned long (*get_cpu_khz)(void);

	/* Segment descriptor handling */
	void (*load_tr_desc)(void);
	void (*load_gdt)(const struct Xgt_desc_struct *);
	void (*load_idt)(const struct Xgt_desc_struct *);
	void (*store_gdt)(struct Xgt_desc_struct *);
	void (*store_idt)(struct Xgt_desc_struct *);
	void (*set_ldt)(const void *desc, unsigned entries);
	unsigned long (*store_tr)(void);
	void (*load_tls)(struct thread_struct *t, unsigned int cpu