sys/boot/pc32/libi386/elf64_freebsd.c

   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  * $FreeBSD: src/sys/boot/i386/libi386/elf64_freebsd.c,v 1.14 2003/08/25 23:28:31 obrien Exp $
  27  * $DragonFly: src/sys/boot/pc32/libi386/elf64_freebsd.c,v 1.3 2008/08/25 16:58:41 dillon Exp $
  28  */
  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
  43 static int      elf64_exec(struct preloaded_file *amp);
  44 static int      elf64_obj_exec(struct preloaded_file *amp);
  45
  46 struct file_format amd64_elf = { elf64_loadfile, elf64_exec };
  47 struct 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
  54 typedef u_int64_t p4_entry_t;
  55 typedef u_int64_t p3_entry_t;
  56 typedef u_int64_t p2_entry_t;
  57 extern p4_entry_t PT4[];
  58 extern p3_entry_t PT3[];
  59 extern p2_entry_t PT2[];
  60
  61 u_int32_t entry_hi;
  62 u_int32_t entry_lo;
  63
  64 extern int amd64_tramp(void);
  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  */
  71 static int
  72 elf64_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);                 /* XXX actually EFUCKUP */
  82     ehdr = (Elf_Ehdr *)&(md->md_data);
  83
  84     err = bi_load64(fp->f_args, &modulep, &kernend);
  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
 122 static int
 123 elf64_obj_exec(struct preloaded_file *fp)
 124 {
 125         return (EFTYPE);
 126 }