elf64_freebsd.c revision 119482 
1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/boot/i386/libi386/elf64_freebsd.c 119482 2003-08-25 23:28:32Z obrien $");
29
30#define __ELF_WORD_SIZE 64
31#include <sys/param.h>
32#include <sys/exec.h>
33#include <sys/linker.h>
34#include <string.h>
35#include <machine/bootinfo.h>
36#include <machine/elf.h>
37#include <stand.h>
38
39#include "bootstrap.h"
40#include "libi386.h"
41#include "btxv86.h"
42
43static int	elf64_exec(struct preloaded_file *amp);
44
45struct file_format amd64_elf = { elf64_loadfile, elf64_exec };
46
47#define PG_V	0x001
48#define PG_RW	0x002
49#define PG_U	0x004
50#define PG_PS	0x080
51
52typedef u_int64_t p4_entry_t;
53typedef u_int64_t p3_entry_t;
54typedef u_int64_t p2_entry_t;
55extern p4_entry_t PT4[];
56extern p3_entry_t PT3[];
57extern p2_entry_t PT2[];
58
59u_int32_t entry_hi;
60u_int32_t entry_lo;
61
62extern amd64_tramp();
63
64/*
65 * There is an a.out kernel and one or more a.out modules loaded.
66 * We wish to start executing the kernel image, so make such
67 * preparations as are required, and do so.
68 */
69static int
70elf64_exec(struct preloaded_file *fp)
71{
72    struct file_metadata	*md;
73    Elf_Ehdr 			*ehdr;
74    vm_offset_t			modulep, kernend;
75    int				err;
76    int				i;
77
78    if ((md = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL)
79	return(EFTYPE);			/* XXX actually EFUCKUP */
80    ehdr = (Elf_Ehdr *)&(md->md_data);
81
82    err = bi_load64(fp->f_args, &modulep, &kernend);
83    if (err != 0)
84	return(err);
85
86    bzero(PT4, PAGE_SIZE);
87    bzero(PT3, PAGE_SIZE);
88    bzero(PT2, PAGE_SIZE);
89
90    /*
91     * This is kinda brutal, but every single 1GB VM memory segment points to
92     * the same first 1GB of physical memory.  But it is more than adequate.
93     */
94    for (i = 0; i < 512; i++) {
95	/* Each slot of the level 4 pages points to the same level 3 page */
96	PT4[i] = (p4_entry_t)VTOP((uintptr_t)&PT3[0]);
97	PT4[i] |= PG_V | PG_RW | PG_U;
98
99	/* Each slot of the level 3 pages points to the same level 2 page */
100	PT3[i] = (p3_entry_t)VTOP((uintptr_t)&PT2[0]);
101	PT3[i] |= PG_V | PG_RW | PG_U;
102
103	/* The level 2 page slots are mapped with 2MB pages for 1GB. */
104	PT2[i] = i * (2 * 1024 * 1024);
105	PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
106    }
107
108    entry_lo = ehdr->e_entry & 0xffffffff;
109    entry_hi = (ehdr->e_entry >> 32) & 0xffffffff;
110#ifdef DEBUG
111    printf("Start @ %#llx ...\n", ehdr->e_entry);
112#endif
113
114    dev_cleanup();
115    __exec((void *)VTOP(amd64_tramp), modulep, kernend);
116
117    panic("exec returned");
118}
119