/**
* Perform a series of memory copies from a list in low memory
*/
static void shuffle ( unsigned int list_segment, unsigned int list_offset, unsigned int count )
{
comboot_shuffle_descriptor shuf[COMBOOT_MAX_SHUFFLE_DESCRIPTORS];
unsigned int i;
/* Copy shuffle descriptor list so it doesn't get overwritten */
copy_from_user ( shuf, real_to_user ( list_segment, list_offset ), 0,
count * sizeof( comboot_shuffle_descriptor ) );
/* Do the copies */
for ( i = 0; i < count; i++ ) {
userptr_t src_u = phys_to_user ( shuf[ i ].src );
userptr_t dest_u = phys_to_user ( shuf[ i ].dest );
if ( shuf[ i ].src == 0xFFFFFFFF ) {
/* Fill with 0 instead of copying */
memset_user ( dest_u, 0, 0, shuf[ i ].len );
} else if ( shuf[ i ].dest == 0xFFFFFFFF ) {
/* Copy new list of descriptors */
count = shuf[ i ].len / sizeof( comboot_shuffle_descriptor );
assert ( count <= COMBOOT_MAX_SHUFFLE_DESCRIPTORS );
copy_from_user ( shuf, src_u, 0, shuf[ i ].len );
i = -1;
} else {
/* Regular copy */
memmove_user ( dest_u, 0, src_u, 0, shuf[ i ].len );
}
}
}
/**
* Prepare segment for loading
*
* @v segment Segment start
* @v filesz Size of the "allocated bytes" portion of the segment
* @v memsz Size of the segment
* @ret rc Return status code
*/
int prep_segment ( userptr_t segment, size_t filesz, size_t memsz ) {
struct memory_map memmap;
physaddr_t start = user_to_phys ( segment, 0 );
physaddr_t mid = user_to_phys ( segment, filesz );
physaddr_t end = user_to_phys ( segment, memsz );
unsigned int i;
DBG ( "Preparing segment [%lx,%lx,%lx)\n", start, mid, end );
/* Sanity check */
if ( filesz > memsz ) {
DBG ( "Insane segment [%lx,%lx,%lx)\n", start, mid, end );
return -EINVAL;
}
/* Get a fresh memory map. This allows us to automatically
* avoid treading on any regions that Etherboot is currently
* editing out of the memory map.
*/
get_memmap ( &memmap );
/* Look for a suitable memory region */
for ( i = 0 ; i < memmap.count ; i++ ) {
if ( ( start >= memmap.regions[i].start ) &&
( end <= memmap.regions[i].end ) ) {
/* Found valid region: zero bss and return */
memset_user ( segment, filesz, 0, ( memsz - filesz ) );
return 0;
}
}
/* No suitable memory region found */
DBG ( "Segment [%lx,%lx,%lx) does not fit into available memory\n",
start, mid, end );
return -ERANGE_SEGMENT;
}
