Base memory allocation. More...

#include <stdint.h>
#include <realmode.h>
#include <bios.h>

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)

static unsigned int	get_fbms (void)
	Read the BIOS free base memory counter. More...

void	set_fbms (unsigned int new_fbms)
	Set the BIOS free base memory counter. More...

void	hide_basemem (void)
	Hide used base memory. More...

Detailed Description

Base memory allocation.

Definition in file basemem.h.

Function Documentation

◆ FILE_LICENCE()

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )

◆ get_fbms()

static unsigned int get_fbms ( void )

inlinestatic

Read the BIOS free base memory counter.

Return values

fbms	Free base memory counter (in kB)

Definition at line 21 of file basemem.h.

                                              {
         uint16_t fbms;
 
         get_real ( fbms, BDA_SEG, BDA_FBMS );
         return fbms;
 }

References BDA_FBMS, BDA_SEG, and get_real.

Referenced by basememsize(), com32_exec_loop(), comboot_init_psp(), hide_basemem(), hide_etherboot(), undi_load(), and undi_unload().

◆ set_fbms()

void set_fbms ( unsigned int new_fbms )

Set the BIOS free base memory counter.

Parameters

new_fbms New free base memory counter (in kB)

Definition at line 43 of file basemem.c.

                                         {
         uint16_t fbms = new_fbms;
 
         /* Update the BIOS memory counter */
         put_real ( fbms, BDA_SEG, BDA_FBMS );
 
         /* Update our hidden memory region map */
         hide_basemem();
 }

References BDA_FBMS, BDA_SEG, hide_basemem(), and put_real.

Referenced by undi_load(), and undi_unload().

◆ hide_basemem()

void hide_basemem ( void )

Hide used base memory.

Definition at line 107 of file hidemem.c.

                            {
         /* Hide from the top of free base memory to 640kB.  Don't use
          * hide_region(), because we don't want this rounded to the
          * nearest page boundary.
          */
         hidemem_base.start = ( get_fbms() * 1024 );
 }

References get_fbms(), and hidemem_base.

Referenced by hide_etherboot(), and set_fbms().