6/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                                           };
  86
  87 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_ANY,
  88         (sysinit_cfunc_t) elf64_insert_brand_entry,
  89         &freebsd_brand_info);
  90
  91 static Elf64_Brandinfo freebsd_brand_oinfo = {
  92                                                 ELFOSABI_FREEBSD,
  93                                                 EM_X86_64,
  94                                                 "FreeBSD",
  95                                                 NULL,
  96                                                 "/usr/libexec/ld-elf.so.1",
  97                                                 &elf64_freebsd_sysvec,
  98                                                 NULL,
  99                                           };
 100
 101 SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
 102         (sysinit_cfunc_t) elf64_insert_brand_entry,
 103         &freebsd_brand_oinfo);
 104
 105
 106 void
 107 elf64_dump_thread(struct thread *td __unused, void *dst __unused,
 108     size_t *off __unused)
 109 {
 110 }
 111
 112
 113 /* Process one elf relocation with addend. */
 114 static int
 115 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
 116     int type, int local, elf_lookup_fn lookup)
 117 {
 118         Elf64_Addr *where, val;
 119         Elf32_Addr *where32, val32;
 120         Elf_Addr addr;
 121         Elf_Addr addend;
 122         Elf_Size rtype, symidx;
 123         const Elf_Rel *rel;
 124         const Elf_Rela *rela;
 125
 126         switch (type) {
 127         case ELF_RELOC_REL:
 128                 rel = (const Elf_Rel *)data;
 129                 where = (Elf_Addr *) (relocbase + rel->r_offset);
 130                 rtype = ELF_R_TYPE(rel->r_info);
 131                 symidx = ELF_R_SYM(rel->r_info);
 132                 /* Addend is 32 bit on 32 bit relocs */
 133                 switch (rtype) {
 134                 case R_X86_64_PC32:
 135                 case R_X86_64_32S:
 136                         addend = *(Elf32_Addr *)where;
 137                         break;
 138                 default:
 139                         addend = *where;
 140                         break;
 141                 }
 142                 break;
 143         case ELF_RELOC_RELA:
 144                 rela = (const Elf_Rela *)data;
 145                 where = (Elf_Addr *) (relocbase + rela->r_offset);
 146                 addend = rela->r_addend;
 147                 rtype = ELF_R_TYPE(rela->r_info);
 148                 symidx = ELF_R_SYM(rela->r_info);
 149                 break;
 150         default:
 151                 panic("unknown reloc type %d\n", type);
 152         }
 153
 154         switch (rtype) {
 155
 156                 case R_X86_64_NONE:     /* none */
 157                         break;
 158
 159                 case R_X86_64_64:               /* S + A */
 160                         addr = lookup(lf, symidx, 1);
 161                         val = addr + addend;
 162                         if (addr == 0)
 163                                 return -1;
 164                         if (*where != val)
 165                                 *where = val;
 166                         break;
 167
 168                 case R_X86_64_PC32:     /* S + A - P */
 169                         addr = lookup(lf, symidx, 1);
 170                         where32 = (Elf32_Addr *)where;
 171                         val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
 172                         if (addr == 0)
 173                                 return -1;
 174                         if (*where32 != val32)
 175                                 *where32 = val32;
 176                         break;
 177
 178                 case R_X86_64_32S:      /* S + A sign extend */
 179                         addr = lookup(lf, symidx, 1);
 180                         val32 = (Elf32_Addr)(addr + addend);
 181                         where32 = (Elf32_Addr *)where;
 182                         if (addr == 0)
 183                                 return -1;
 184                         if (*where32 != val32)
 185                                 *where32 = val32;
 186                         break;
 187
 188                 case R_X86_64_COPY:     /* none */
 189                         /*
 190                          * There shouldn't be copy relocations in kernel
 191                          * objects.
 192                          */
 193                         printf("kldload: unexpected R_COPY relocation\n");
 194                         return -1;
 195                         break;
 196
 197                 case R_X86_64_GLOB_DAT: /* S */
 198                         addr = lookup(lf, symidx, 1);
 199                         if (addr == 0)
 200                                 return -1;
 201                         if (*where != addr)
 202                                 *where = addr;
 203                         break;
 204
 205                 case R_X86_64_RELATIVE: /* B + A */
 206                         addr = relocbase + addend;
 207                         val = addr;
 208                         if (*where != val)
 209                                 *where = val;
 210                         break;
 211
 212                 default:
 213                         printf("kldload: unexpected relocation type %ld\n",
 214                                rtype);
 215                         return -1;
 216         }
 217         return(0);
 218 }
 219
 220 int
 221 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
 222     elf_lookup_fn lookup)
 223 {
 224
 225         return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
 226 }
 227
 228 int
 229 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
 230     int type, elf_lookup_fn lookup)
 231 {
 232
 233         return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
 234 }
 235
 236 int
 237 elf_cpu_load_file(linker_file_t lf __unused)
 238 {
 239
 240         return (0);
 241 }
 242
 243 int
 244 elf_cpu_unload_file(linker_file_t lf __unused)
 245 {
 246
 247         return (0);
 248 }