#ifndef LIBRM_H
#define LIBRM_H
/* Drag in protected-mode segment selector values */
#include "virtaddr.h"
#include "realmode.h"
#ifndef ASSEMBLY
#include "stddef.h"
#include "string.h"
/*
* Data structures and type definitions
*
*/
/* Real-mode call parameter block, as passed to real_call */
struct real_call_params {
struct i386_seg_regs;
struct i386_regs;
segoff_t rm_code;
segoff_t reserved;
} PACKED;
/* Current location of librm in base memory */
extern char *installed_librm;
/* Start and size of our source copy of librm (i.e. the one that we
* can install by copying it to base memory and setting
* installed_librm)
*/
extern char librm[];
extern size_t _librm_size[];
/* Linker symbols for offsets within librm. Other symbols should
* almost certainly not be referred to from C code.
*/
extern void (*_real_to_prot[]) ( void );
extern void (*_prot_to_real[]) ( void );
extern void (*_prot_call[]) ( void );
extern void (*_real_call[]) ( void );
extern segoff_t _rm_stack[];
extern uint32_t _pm_stack[];
extern char _librm_ref_count[];
/* Symbols within current installation of librm */
#define LIBRM_VAR( sym ) \
( * ( ( typeof ( * _ ## sym ) * ) \
& ( installed_librm [ (int) _ ## sym ] ) ) )
#define LIBRM_FN( sym ) \
( ( typeof ( * _ ## sym ) ) \
& ( installed_librm [ (int) _ ## sym ] ) )
#define LIBRM_CONSTANT( sym ) \
( ( typeof ( * _ ## sym ) ) ( _ ## sym ) )
#define inst_real_to_prot LIBRM_FN ( real_to_prot )
#define inst_prot_to_real LIBRM_FN ( prot_to_real )
#define inst_prot_call LIBRM_FN ( prot_call )
#define inst_real_call LIBRM_FN ( real_call )
#define inst_rm_stack LIBRM_VAR ( rm_stack )
#define inst_pm_stack LIBRM_VAR ( pm_stack )
#define inst_librm_ref_count LIBRM_VAR ( librm_ref_count )
#define librm_size LIBRM_CONSTANT ( librm_size )
/* Functions that librm expects to be able to link to. Included here
* so that the compiler will catch prototype mismatches.
*/
extern void _phys_to_virt ( void );
extern void _virt_to_phys ( void );
extern void gateA20_set ( void );
/*
* librm_mgmt: functions for manipulating base memory and executing
* real-mode code.
*
* Full API documentation for these functions is in realmode.h.
*
*/
/* Macro for obtaining a physical address from a segment:offset pair. */
#define VIRTUAL(x,y) ( phys_to_virt ( ( ( x ) << 4 ) + ( y ) ) )
/* Copy to/from base memory */
static inline void copy_to_real_librm ( uint16_t dest_seg, uint16_t dest_off,
void *src, size_t n ) {
memcpy ( VIRTUAL ( dest_seg, dest_off ), src, n );
}
static inline void copy_from_real_librm ( void *dest,
uint16_t src_seg, uint16_t src_off,
size_t n ) {
memcpy ( dest, VIRTUAL ( src_seg, src_off ), n );
}
#define put_real_librm( var, dest_seg, dest_off ) \
do { \
* ( ( typeof(var) * ) VIRTUAL ( dest_seg, dest_off ) ) = var; \
} while ( 0 )
#define get_real_librm( var, src_seg, src_off ) \
do { \
var = * ( ( typeof(var) * ) VIRTUAL ( src_seg, src_off ) ); \
} while ( 0 )
#define copy_to_real copy_to_real_librm
#define copy_from_real copy_from_real_librm
#define put_real put_real_librm
#define get_real get_real_librm
/* Copy to/from real-mode stack */
extern uint16_t copy_to_rm_stack ( void *data, size_t size );
extern void remove_from_rm_stack ( void *data, size_t size );
/* Place/remove parameter on real-mode stack in a way that's
* compatible with libkir
*/
#define BASEMEM_PARAMETER_INIT_LIBRM( param ) \
copy_to_rm_stack ( & ( param ), sizeof ( param ) )
#define BASEMEM_PARAMETER_DONE_LIBRM( param ) \
remove_from_rm_stack ( & ( param ), sizeof ( param ) )
#define BASEMEM_PARAMETER_INIT BASEMEM_PARAMETER_INIT_LIBRM
#define BASEMEM_PARAMETER_DONE BASEMEM_PARAMETER_DONE_LIBRM
/* REAL_FRAGMENT: Declare and define a real-mode code fragment in .text16 */
#define REAL_FRAGMENT( name, asm_code_str ) \
extern void name ( void ); \
extern char name ## _size[]; \
__asm__ __volatile__ ( \
".section \".text16\"\n\t" \
".code16\n\t" \
".arch i386\n\t" \
#name ":\n\t" \
asm_code_str "\n\t" \
"lret\n\t" \
#name "_end:\n\t" \
".equ " #name "_size, " #name "_end - " #name "\n\t" \
".code32\n\t" \
".previous\n\t" \
: : \
)
#define FRAGMENT_SIZE( fragment ) ( (size_t) fragment ## _size )
/* REAL_CALL: call a real-mode routine via librm */
#define OUT_CONSTRAINTS(...) __VA_ARGS__
#define IN_CONSTRAINTS(...) "m" ( __routine ), ## __VA_ARGS__
#define CLOBBER(...) __VA_ARGS__
#define REAL_CALL( routine, num_out_constraints, out_constraints, \
in_constraints, clobber ) \
do { \
segoff_t __routine = routine; \
__asm__ __volatile__ ( \
"pushl %" #num_out_constraints "\n\t" \
"call 1f\n\t" \
"jmp 2f\n\t" \
"\n1:\n\t" \
"pushl installed_librm\n\t" \
"addl $_real_call, 0(%%esp)\n\t" \
"ret\n\t" \
"\n2:\n\t" \
"addl $4, %%esp\n\t" \
: out_constraints \
: in_constraints \
: clobber \
); \
} while ( 0 )
/* REAL_EXEC: combine RM_FRAGMENT and REAL_CALL into one handy unit */
#define PASSTHRU(...) __VA_ARGS__
#define REAL_EXEC( name, asm_code_str, num_out_constraints, out_constraints, \
in_constraints, clobber ) \
do { \
segoff_t fragment; \
\
REAL_FRAGMENT ( name, asm_code_str ); \
\
fragment.segment = inst_rm_stack.segment; \
fragment.offset = \
copy_to_rm_stack ( name, FRAGMENT_SIZE ( name ) ); \
\
REAL_CALL ( fragment, num_out_constraints, \
PASSTHRU ( out_constraints ), \
PASSTHRU ( in_constraints ), \
PASSTHRU ( clobber ) ); \
\
remove_from_rm_stack ( NULL, FRAGMENT_SIZE ( name ) ); \
} while ( 0 )
#endif /* ASSEMBLY */
#endif /* LIBRM_H */
