sys/amd64/amd64/elf_machdep.c

   1 /*-
   2  * Copyright 1996-1998 John D. Polstra.
   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 ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include <sys/cdefs.h>
  27 __FBSDID("$FreeBSD$");
  28
  29 #include <sys/param.h>
  30 #include <sys/kernel.h>
  31 #include <sys/systm.h>
  32 #include <sys/exec.h>
  33 #include <sys/imgact.h>
  34 #include <sys/linker.h>
  35 #include <sys/sysent.h>
  36 #include <sys/imgact_elf.h>
  37 #include <sys/syscall.h>
  38 #include <sys/signalvar.h>
  39 #include <sys/vnode.h>
  40
  41 #include <vm/vm.h>
  42 #include <vm/pmap.h>
  43 #include <vm/vm_param.h>
  44
  45 #include <machine/elf.h>
  46 #include <machine/md_var.h>
  47
  48 struct sysentvec elf64_freebsd_sysvec = {
  49         SYS_MAXSYSCALL,
  50         sysent,
  51         0,
  52         0,
  53         NULL,
  54         0,
  55         NULL,
  56         NULL,
  57         __elfN(freebsd_fixup),
  58         sendsig,
  59         sigcode,
  60         &szsigcode,
  61         NULL,
  62         "FreeBSD ELF64",
  63         __elfN(coredump),
  64         NULL,
  65         MINSIGSTKSZ,
  66         PAGE_SIZE,
  67         VM_MIN_ADDRESS,
  68         VM_MAXUSER_ADDRESS,
  69         USRSTACK,
  70         PS_STRINGS,
  71         VM_PROT_ALL,
  72         exec_copyout_strings,
  73         exec_setregs,
  74         NULL
  75 };
  76
  77 static Elf64_Brandinfo freebsd_brand_info = {
  78                                                 ELFOSABI_FREEBSD,
  79                                                 EM_X86_64,
  80                                                 "FreeBSD",
  81                                                 NULL,
  82                                                 "/libexec/ld-elf.so.1",
  83                                                 &elf64_freebsd_sysvec,
  84                                                 NULL,
  85                                                 0,
  86                                           };
  87
  88 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_ANY,
  89         (sysinit_cfunc_t) elf64_insert_brand_entry,
  90         &freebsd_brand_info);
  91
  92 static Elf64_Brandinfo freebsd_brand_oinfo = {
  93                                                 ELFOSABI_FREEBSD,
  94                                                 EM_X86_64,
  95                                                 "FreeBSD",
  96                                                 NULL,
  97                                                 "/usr/libexec/ld-elf.so.1",
  98                                                 &elf64_freebsd_sysvec,
  99                                                 NULL,
 100                                                 0,
 101                                           };
 102
 103 SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
 104         (sysinit_cfunc_t) elf64_insert_brand_entry,
 105         &freebsd_brand_oinfo);
 106
 107
 108 void
 109 elf64_dump_thread(struct thread *td __unused, void *dst __unused,
 110     size_t *off __unused)
 111 {
 112 }
 113
 114
 115 /* Process one elf relocation with addend. */
 116 static int
 117 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
 118     int type, int local, elf_lookup_fn lookup)
 119 {
 120         Elf64_Addr *where, val;
 121         Elf32_Addr *where32, val32;
 122         Elf_Addr addr;
 123         Elf_Addr addend;
 124         Elf_Size rtype, symidx;
 125         const Elf_Rel *rel;
 126         const Elf_Rela *rela;
 127
 128         switch (type) {
 129         case ELF_RELOC_REL:
 130                 rel = (const Elf_Rel *)data;
 131                 where = (Elf_Addr *) (relocbase + rel->r_offset);
 132                 rtype = ELF_R_TYPE(rel->r_info);
 133                 symidx = ELF_R_SYM(rel->r_info);
 134                 /* Addend is 32 bit on 32 bit relocs */
 135                 switch (rtype) {
 136                 case R_X86_64_PC32:
 137                 case R_X86_64_32S:
 138                         addend = *(Elf32_Addr *)where;
 139                         break;
 140                 default:
 141                         addend = *where;
 142                         break;
 143                 }
 144                 break;
 145         case ELF_RELOC_RELA:
 146                 rela = (const Elf_Rela *)data;
 147                 where = (Elf_Addr *) (relocbase + rela->r_offset);
 148                 addend = rela->r_addend;
 149                 rtype = ELF_R_TYPE(rela->r_info);
 150                 symidx = ELF_R_SYM(rela->r_info);
 151                 break;
 152         default:
 153                 panic("unknown reloc type %d\n", type);
 154         }
 155
 156         switch (rtype) {
 157
 158                 case R_X86_64_NONE:     /* none */
 159                         break;
 160
 161                 case R_X86_64_64:               /* S + A */
 162                         addr = lookup(lf, symidx, 1);
 163                         val = addr + addend;
 164                         if (addr == 0)
 165                                 return -1;
 166                         if (*where != val)
 167                                 *where = val;
 168                         break;
 169
 170                 case R_X86_64_PC32:     /* S + A - P */
 171                         addr = lookup(lf, symidx, 1);
 172                         where32 = (Elf32_Addr *)where;
 173                         val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
 174                         if (addr == 0)
 175                                 return -1;
 176                         if (*where32 != val32)
 177                                 *where32 = val32;
 178                         break;
 179
 180                 case R_X86_64_32S:      /* S + A sign extend */
 181                         addr = lookup(lf, symidx, 1);
 182                         val32 = (Elf32_Addr)(addr + addend);
 183                         where32 = (Elf32_Addr *)where;
 184                         if (addr == 0)
 185                                 return -1;
 186                         if (*where32 != val32)
 187                                 *where32 = val32;
 188                         break;
 189
 190                 case R_X86_64_COPY:     /* none */
 191                         /*
 192                          * There shouldn't be copy relocations in kernel
 193                          * objects.
 194                          */
 195                         printf("kldload: unexpected R_COPY relocation\n");
 196                         return -1;
 197                         break;
 198
 199                 case R_X86_64_GLOB_DAT: /* S */
 200                 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */
 201                         addr = lookup(lf, symidx, 1);
 202                         if (addr == 0)
 203                                 return -1;
 204                         if (*where != addr)
 205                                 *where = addr;
 206                         break;
 207
 208                 case R_X86_64_RELATIVE: /* B + A */
 209                         addr = relocbase + addend;
 210                         val = addr;
 211                         if (*where != val)
 212                                 *where = val;
 213                         break;
 214
 215                 default:
 216                         printf("kldload: unexpected relocation type %ld\n",
 217                                rtype);
 218                         return -1;
 219         }
 220         return(0);
 221 }
 222
 223 int
 224 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
 225     elf_lookup_fn lookup)
 226 {
 227
 228         return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
 229 }
 230
 231 int
 232 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
 233     int type, elf_lookup_fn lookup)
 234 {
 235
 236         return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
 237 }
 238
 239 int
 240 elf_cpu_load_file(linker_file_t lf __unused)
 241 {
 242
 243         return (0);
 244 }
 245
 246 int
 247 elf_cpu_unload_file(linker_file_t lf __unused)
 248 {
 249
 250         return (0);
 251 }