#ifndef LIBRM_H
#define LIBRM_H
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
/* Segment selectors as used in our protected-mode GDTs.
*
* Don't change these unless you really know what you're doing.
*/
#define VIRTUAL_CS 0x08
#define VIRTUAL_DS 0x10
#define PHYSICAL_CS 0x18
#define PHYSICAL_DS 0x20
#define REAL_CS 0x28
#define REAL_DS 0x30
#define P2R_DS 0x38
#ifdef ASSEMBLY
/**
* Call C function from real-mode code
*
* @v function C function
*/
.macro virtcall function
pushl $\function
call prot_call
.endm
#else /* ASSEMBLY */
#ifdef UACCESS_LIBRM
#define UACCESS_PREFIX_librm
#else
#define UACCESS_PREFIX_librm __librm_
#endif
/**
* Call C function from real-mode code
*
* @v function C function
*/
#define VIRT_CALL( function ) \
"pushl $( " #function " )\n\t" \
"call prot_call\n\t"
/* Variables in librm.S */
extern unsigned long virt_offset;
/**
* Convert physical address to user pointer
*
* @v phys_addr Physical address
* @ret userptr User pointer
*/
static inline __always_inline userptr_t
UACCESS_INLINE ( librm, phys_to_user ) ( unsigned long phys_addr ) {
return ( phys_addr - virt_offset );
}
/**
* Convert user buffer to physical address
*
* @v userptr User pointer
* @v offset Offset from user pointer
* @ret phys_addr Physical address
*/
static inline __always_inline unsigned long
UACCESS_INLINE ( librm, user_to_phys ) ( userptr_t userptr, off_t offset ) {
return ( userptr + offset + virt_offset );
}
static inline __always_inline userptr_t
UACCESS_INLINE ( librm, virt_to_user ) ( volatile const void *addr ) {
return trivial_virt_to_user ( addr );
}
static inline __always_inline void *
UACCESS_INLINE ( librm, user_to_virt ) ( userptr_t userptr, off_t offset ) {
return trivial_user_to_virt ( userptr, offset );
}
static inline __always_inline userptr_t
UACCESS_INLINE ( librm, userptr_add ) ( userptr_t userptr, off_t offset ) {
return trivial_userptr_add ( userptr, offset );
}
static inline __always_inline off_t
UACCESS_INLINE ( librm, userptr_sub ) ( userptr_t userptr,
userptr_t subtrahend ) {
return trivial_userptr_sub ( userptr, subtrahend );
}
static inline __always_inline void
UACCESS_INLINE ( librm, memcpy_user ) ( userptr_t dest, off_t dest_off,
userptr_t src, off_t src_off,
size_t len ) {
trivial_memcpy_user ( dest, dest_off, src, src_off, len );
}
static inline __always_inline void
UACCESS_INLINE ( librm, memmove_user ) ( userptr_t dest, off_t dest_off,
userptr_t src, off_t src_off,
size_t len ) {
trivial_memmove_user ( dest, dest_off, src, src_off, len );
}
static inline __always_inline int
UACCESS_INLINE ( librm, memcmp_user ) ( userptr_t first, off_t first_off,
userptr_t second, off_t second_off,
size_t len ) {
return trivial_memcmp_user ( first, first_off, second, second_off, len);
}
static inline __always_inline void
UACCESS_INLINE ( librm, memset_user ) ( userptr_t buffer, off_t offset,
int c, size_t len ) {
trivial_memset_user ( buffer, offset, c, len );
}
static inline __always_inline size_t
UACCESS_INLINE ( librm, strlen_user ) ( userptr_t buffer, off_t offset ) {
return trivial_strlen_user ( buffer, offset );
}
static inline __always_inline off_t
UACCESS_INLINE ( librm, memchr_user ) ( userptr_t buffer, off_t offset,
int c, size_t len ) {
return trivial_memchr_user ( buffer, offset, c, len );
}
/******************************************************************************
*
* Access to variables in .data16 and .text16
*
*/
extern char *data16;
extern char *text16;
#define __data16( variable ) \
__attribute__ (( section ( ".data16" ) )) \
_data16_ ## variable __asm__ ( #variable )
#define __data16_array( variable, array ) \
__attribute__ (( section ( ".data16" ) )) \
_data16_ ## variable array __asm__ ( #variable )
#define __bss16( variable ) \
__attribute__ (( section ( ".bss16" ) )) \
_data16_ ## variable __asm__ ( #variable )
#define __bss16_array( variable, array ) \
__attribute__ (( section ( ".bss16" ) )) \
_data16_ ## variable array __asm__ ( #variable )
#define __text16( variable ) \
__attribute__ (( section ( ".text16.data" ) )) \
_text16_ ## variable __asm__ ( #variable )
#define __text16_array( variable, array ) \
__attribute__ (( section ( ".text16.data" ) )) \
_text16_ ## variable array __asm__ ( #variable )
#define __use_data16( variable ) \
( * ( ( typeof ( _data16_ ## variable ) * ) \
& ( data16 [ ( size_t ) & ( _data16_ ## variable ) ] ) ) )
#define __use_text16( variable ) \
( * ( ( typeof ( _text16_ ## variable ) * ) \
& ( text16 [ ( size_t ) & ( _text16_ ## variable ) ] ) ) )
#define __from_data16( pointer ) \
( ( unsigned int ) \
( ( ( void * ) (pointer) ) - ( ( void * ) data16 ) ) )
#define __from_text16( pointer ) \
( ( unsigned int ) \
( ( ( void * ) (pointer) ) - ( ( void * ) text16 ) ) )
/* Variables in librm.S, present in the normal data segment */
extern uint16_t rm_sp;
extern uint16_t rm_ss;
extern uint16_t __text16 ( rm_cs );
#define rm_cs __use_text16 ( rm_cs )
extern uint16_t __text16 ( rm_ds );
#define rm_ds __use_text16 ( rm_ds )
extern uint16_t copy_user_to_rm_stack ( userptr_t data, size_t size );
extern void remove_user_from_rm_stack ( userptr_t data, size_t size );
/* CODE_DEFAULT: restore default .code32/.code64 directive */
#ifdef __x86_64__
#define CODE_DEFAULT ".code64"
#else
#define CODE_DEFAULT ".code32"
#endif
/* TEXT16_CODE: declare a fragment of code that resides in .text16 */
#define TEXT16_CODE( asm_code_str ) \
".section \".text16\", \"ax\", @progbits\n\t" \
".code16\n\t" \
asm_code_str "\n\t" \
CODE_DEFAULT "\n\t" \
".previous\n\t"
/* REAL_CODE: declare a fragment of code that executes in real mode */
#define REAL_CODE( asm_code_str ) \
"push $1f\n\t" \
"call real_call\n\t" \
TEXT16_CODE ( "\n1:\n\t" \
asm_code_str \
"\n\t" \
"ret\n\t" )
/* PHYS_CODE: declare a fragment of code that executes in flat physical mode */
#define PHYS_CODE( asm_code_str ) \
"call _virt_to_phys\n\t" \
".code32\n\t" \
asm_code_str \
"call _phys_to_virt\n\t" \
CODE_DEFAULT "\n\t"
/** Number of interrupts */
#define NUM_INT 256
/** An interrupt descriptor table register */
struct idtr {
/** Limit */
uint16_t limit;
/** Base */
uint32_t base;
} __attribute__ (( packed ));
/** An interrupt descriptor table entry */
struct interrupt_descriptor {
/** Low 16 bits of address */
uint16_t low;
/** Code segment */
uint16_t segment;
/** Unused */
uint8_t unused;
/** Type and attributes */
uint8_t attr;
/** High 16 bits of address */
uint16_t high;
} __attribute__ (( packed ));
/** Interrupt descriptor is present */
#define IDTE_PRESENT 0x80
/** Interrupt descriptor 32-bit interrupt gate type */
#define IDTE_TYPE_IRQ32 0x0e
/** An interrupt vector
*
* Each interrupt vector comprises an eight-byte fragment of code:
*
* 60 pushal
* b0 xx movb $INT, %al
* e9 xx xx xx xx jmp interrupt_wrapper
*/
struct interrupt_vector {
/** "pushal" instruction */
uint8_t pushal;
/** "movb" instruction */
uint8_t movb;
/** Interrupt number */
uint8_t intr;
/** "jmp" instruction */
uint8_t jmp;
/** Interrupt wrapper address offset */
uint32_t offset;
/** Next instruction after jump */
uint8_t next[0];
} __attribute__ (( packed ));
/** "pushal" instruction */
#define PUSHAL_INSN 0x60
/** "movb" instruction */
#define MOVB_INSN 0xb0
/** "jmp" instruction */
#define JMP_INSN 0xe9
extern void set_interrupt_vector ( unsigned int intr, void *vector );
#endif /* ASSEMBLY */
#endif /* LIBRM_H */
