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Heading towards a sane set of control functions

This commit is contained in:
Michael Brown 2005-04-10 18:21:53 +00:00
parent 39cb1b4f9e
commit 560027899e
1 changed files with 39 additions and 27 deletions
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66
src/arch/i386/transitions/librm_mgmt.c
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@ -12,8 +12,9 @@
#include "stdint.h"
#include "stddef.h"
#include "string.h"
#include "init.h"
#include "basemem.h"
#include "relocate.h"
#include "init.h"
#include "librm.h"
/*
@ -78,10 +79,21 @@ static void install_librm ( char *addr ) {
* preserving the values for rm_ss and rm_sp from the old installed
* copy.
*
* We deliberately leave the old copy intact and effectively installed
* (apart from being in unallocated memory) so that we can use it for
* any real-mode calls required when allocating memory for the new
* copy, or for the real-mode exit path.
*/
static void uninstall_librm ( void ) {
/* Copy installed librm back to master copy */
memcpy ( librm, installed_librm, librm_size );
librm_base = 0;
/* Free but do not zero the base memory */
if ( allocated_librm ) {
free_base_memory ( installed_librm, librm_size );
allocated_librm = 0;
}
}
/*
@ -101,49 +113,49 @@ static void librm_init ( void ) {
}
/*
* On exit, we want to leave a copy of librm in *unallocated* base
* memory. It must be there so that we can exit via a 16-bit exit
* path, but it must not be allocated because nothing will ever
* deallocate it once we exit.
* librm_post_reloc gets called immediately after relocation.
*
*/
static void librm_exit ( void ) {
/* Free but do not zero the base memory */
if ( allocated_librm ) {
free_base_memory ( installed_librm, librm_size );
allocated_librm = 0;
}
static void librm_post_reloc ( void ) {
/* Point installed_librm back at last known physical location.
*/
installed_librm = phys_to_virt ( librm_base );
}
INIT_FN ( INIT_LIBRM, librm_init, NULL, uninstall_librm );
POST_RELOC_FN ( POST_RELOC_LIBRM, librm_post_reloc );
/*
* Reset gets called immediately after relocation.
* Wrapper for arch_initialise() when librm is being used. We have to
* install a copy of librm to allocated base memory and return the
* pointer to this new librm's entry point via es:di.
*
*/
static void librm_reset ( void ) {
void librm_arch_initialise ( struct i386_all_regs *regs ) {
char *new_librm;
/* Point installed_librm back at last known physical location.
* Do this in case we have just relocated and the virtual
* address has therefore changed. */
installed_librm = phys_to_virt ( librm_base );
/* Hand off to arch_initialise() */
arch_initialise ( regs );
/* Free allocated base memory, if applicable */
librm_exit();
/* Uninstall current librm (i.e. the one that's part of the
* original, pre-relocation Etherboot image).
*/
uninstall_librm();
/* Allocate space for new librm */
new_librm = alloc_base_memory ( librm_size );
allocated_librm = 1;
/* Install new librm */
install_librm ( new_librm );
/* Point es:di to new librm's entry point. Fortunately, di is
* already set up by setup16, so all we need to do is point
* es:0000 to the start of the new librm.
*/
regs->es = librm_base >> 4;
}
INIT_FN ( INIT_LIBRM, librm_init, librm_reset, librm_exit );
/*
* Increment lock count of librm
*