elf64_freebsd.c revision 332154 
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: stable/11/stand/i386/libi386/elf64_freebsd.c 332154 2018-04-06 21:37:25Z kevans $");
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);
44static int	elf64_obj_exec(struct preloaded_file *amp);
45
46struct file_format amd64_elf = { elf64_loadfile, elf64_exec };
47struct file_format amd64_elf_obj = { elf64_obj_loadfile, elf64_obj_exec };
48
49#define PG_V	0x001
50#define PG_RW	0x002
51#define PG_U	0x004
52#define PG_PS	0x080
53
54typedef uint64_t p4_entry_t;
55typedef uint64_t p3_entry_t;
56typedef uint64_t p2_entry_t;
57extern p4_entry_t PT4[];
58extern p3_entry_t PT3[];
59extern p2_entry_t PT2[];
60
61uint32_t entry_hi;
62uint32_t entry_lo;
63
64extern void amd64_tramp();
65
66/*
67 * There is an ELF kernel and one or more ELF modules loaded.
68 * We wish to start executing the kernel image, so make such
69 * preparations as are required, and do so.
70 */
71static int
72elf64_exec(struct preloaded_file *fp)
73{
74    struct file_metadata	*md;
75    Elf_Ehdr 			*ehdr;
76    vm_offset_t			modulep, kernend;
77    int				err;
78    int				i;
79
80    if ((md = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL)
81	return(EFTYPE);
82    ehdr = (Elf_Ehdr *)&(md->md_data);
83
84    err = bi_load64(fp->f_args, 0, &modulep, &kernend, 1);
85    if (err != 0)
86	return(err);
87
88    bzero(PT4, PAGE_SIZE);
89    bzero(PT3, PAGE_SIZE);
90    bzero(PT2, PAGE_SIZE);
91
92    /*
93     * This is kinda brutal, but every single 1GB VM memory segment points to
94     * the same first 1GB of physical memory.  But it is more than adequate.
95     */
96    for (i = 0; i < 512; i++) {
97	/* Each slot of the level 4 pages points to the same level 3 page */
98	PT4[i] = (p4_entry_t)VTOP((uintptr_t)&PT3[0]);
99	PT4[i] |= PG_V | PG_RW | PG_U;
100
101	/* Each slot of the level 3 pages points to the same level 2 page */
102	PT3[i] = (p3_entry_t)VTOP((uintptr_t)&PT2[0]);
103	PT3[i] |= PG_V | PG_RW | PG_U;
104
105	/* The level 2 page slots are mapped with 2MB pages for 1GB. */
106	PT2[i] = i * (2 * 1024 * 1024);
107	PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
108    }
109
110    entry_lo = ehdr->e_entry & 0xffffffff;
111    entry_hi = (ehdr->e_entry >> 32) & 0xffffffff;
112#ifdef DEBUG
113    printf("Start @ %#llx ...\n", ehdr->e_entry);
114#endif
115
116    dev_cleanup();
117    __exec((void *)VTOP(amd64_tramp), modulep, kernend);
118
119    panic("exec returned");
120}
121
122static int
123elf64_obj_exec(struct preloaded_file *fp)
124{
125	return (EFTYPE);
126}
127