1/*
2 * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19FILE_LICENCE ( GPL2_OR_LATER );
20
21/**
22 * @file
23 *
24 * Executable image segments
25 *
26 */
27
28#include <errno.h>
29#include <gpxe/uaccess.h>
30#include <gpxe/memmap.h>
31#include <gpxe/errortab.h>
32#include <gpxe/segment.h>
33
34/**
35 * Prepare segment for loading
36 *
37 * @v segment		Segment start
38 * @v filesz		Size of the "allocated bytes" portion of the segment
39 * @v memsz		Size of the segment
40 * @ret rc		Return status code
41 */
42int prep_segment ( userptr_t segment, size_t filesz, size_t memsz ) {
43	struct memory_map memmap;
44	physaddr_t start = user_to_phys ( segment, 0 );
45	physaddr_t mid = user_to_phys ( segment, filesz );
46	physaddr_t end = user_to_phys ( segment, memsz );
47	unsigned int i;
48
49	DBG ( "Preparing segment [%lx,%lx,%lx)\n", start, mid, end );
50
51	/* Sanity check */
52	if ( filesz > memsz ) {
53		DBG ( "Insane segment [%lx,%lx,%lx)\n", start, mid, end );
54		return -EINVAL;
55	}
56
57	/* Get a fresh memory map.  This allows us to automatically
58	 * avoid treading on any regions that Etherboot is currently
59	 * editing out of the memory map.
60	 */
61	get_memmap ( &memmap );
62
63	/* Look for a suitable memory region */
64	for ( i = 0 ; i < memmap.count ; i++ ) {
65		if ( ( start >= memmap.regions[i].start ) &&
66		     ( end <= memmap.regions[i].end ) ) {
67			/* Found valid region: zero bss and return */
68			memset_user ( segment, filesz, 0, ( memsz - filesz ) );
69			return 0;
70		}
71	}
72
73	/* No suitable memory region found */
74	DBG ( "Segment [%lx,%lx,%lx) does not fit into available memory\n",
75	      start, mid, end );
76	return -ERANGE;
77}
78
79/**
80 * Segment-specific error messages
81 *
82 * This error happens sufficiently often to merit a user-friendly
83 * description.
84 */
85struct errortab segment_errors[] __errortab = {
86	{ ERANGE, "Requested memory not available" },
87};
88