LXR linux/arch/m32r/kernel/module.c

   1/*  Kernel module help for M32R.
   2
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; either version 2 of the License, or
   6    (at your option) any later version.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12
  13    You should have received a copy of the GNU General Public License
  14    along with this program; if not, write to the Free Software
  15    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16*/
  17
  18#include <linux/moduleloader.h>
  19#include <linux/elf.h>
  20#include <linux/vmalloc.h>
  21#include <linux/fs.h>
  22#include <linux/string.h>
  23#include <linux/kernel.h>
  24
  25#if 0
  26#define DEBUGP printk
  27#else
  28#define DEBUGP(fmt...)
  29#endif
  30
  31void *module_alloc(unsigned long size)
  32{
  33        if (size == 0)
  34                return NULL;
  35#ifdef CONFIG_MMU
  36        return vmalloc_exec(size);
  37#else
  38        return vmalloc(size);
  39#endif
  40}
  41
  42
  43/* Free memory returned from module_alloc */
  44void module_free(struct module *mod, void *module_region)
  45{
  46        vfree(module_region);
  47}
  48
  49/* We don't need anything special. */
  50int module_frob_arch_sections(Elf_Ehdr *hdr,
  51                              Elf_Shdr *sechdrs,
  52                              char *secstrings,
  53                              struct module *mod)
  54{
  55        return 0;
  56}
  57
  58#define COPY_UNALIGNED_WORD(sw, tw, align) \
  59{ \
  60        void *__s = &(sw), *__t = &(tw); \
  61        unsigned short *__s2 = __s, *__t2 =__t; \
  62        unsigned char *__s1 = __s, *__t1 =__t; \
  63        switch ((align)) \
  64        { \
  65        case 0: \
  66                *(unsigned long *) __t = *(unsigned long *) __s; \
  67                break; \
  68        case 2: \
  69                *__t2++ = *__s2++; \
  70                *__t2 = *__s2; \
  71                break; \
  72        default: \
  73                *__t1++ = *__s1++; \
  74                *__t1++ = *__s1++; \
  75                *__t1++ = *__s1++; \
  76                *__t1 = *__s1; \
  77                break; \
  78        } \
  79}
  80
  81#define COPY_UNALIGNED_HWORD(sw, tw, align) \
  82  { \
  83    void *__s = &(sw), *__t = &(tw); \
  84    unsigned short *__s2 = __s, *__t2 =__t; \
  85    unsigned char *__s1 = __s, *__t1 =__t; \
  86    switch ((align)) \
  87    { \
  88    case 0: \
  89      *__t2 = *__s2; \
  90      break; \
  91    default: \
  92      *__t1++ = *__s1++; \
  93      *__t1 = *__s1; \
  94      break; \
  95    } \
  96  }
  97
  98int apply_relocate_add(Elf32_Shdr *sechdrs,
  99                   const char *strtab,
 100                   unsigned int symindex,
 101                   unsigned int relsec,
 102                   struct module *me)
 103{
 104        unsigned int i;
 105        Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
 106        Elf32_Sym *sym;
 107        Elf32_Addr relocation;
 108        uint32_t *location;
 109        uint32_t value;
 110        unsigned short *hlocation;
 111        unsigned short hvalue;
 112        int svalue;
 113        int align;
 114
 115        DEBUGP("Applying relocate section %u to %u\n", relsec,
 116               sechdrs[relsec].sh_info);
 117        for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
 118                /* This is where to make the change */
 119                location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
 120                        + rel[i].r_offset;
 121                /* This is the symbol it is referring to.  Note that all
 122                   undefined symbols have been resolved.  */
 123                sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
 124                        + ELF32_R_SYM(rel[i].r_info);
 125                relocation = sym->st_value + rel[i].r_addend;
 126                align = (int)location & 3;
 127
 128                switch (ELF32_R_TYPE(rel[i].r_info)) {
 129                case R_M32R_32_RELA:
 130                        COPY_UNALIGNED_WORD (*location, value, align);
 131                        value += relocation;
 132                        COPY_UNALIGNED_WORD (value, *location, align);
 133                        break;
 134                case R_M32R_HI16_ULO_RELA:
 135                        COPY_UNALIGNED_WORD (*location, value, align);
 136                        relocation = (relocation >>16) & 0xffff;
 137                        /* RELA must has 0 at relocation field. */
 138                        value += relocation;
 139                        COPY_UNALIGNED_WORD (value, *location, align);
 140                        break;
 141                case R_M32R_HI16_SLO_RELA:
 142                        COPY_UNALIGNED_WORD (*location, value, align);
 143                        if (relocation & 0x8000) relocation += 0x10000;
 144                        relocation = (relocation >>16) & 0xffff;
 145                        /* RELA must has 0 at relocation field. */
 146                        value += relocation;
 147                        COPY_UNALIGNED_WORD (value, *location, align);
 148                        break;
 149                case R_M32R_16_RELA:
 150                        hlocation = (unsigned short *)location;
 151                        relocation = relocation & 0xffff;
 152                        /* RELA must has 0 at relocation field. */
 153                        hvalue = relocation;
 154                        COPY_UNALIGNED_WORD (hvalue, *hlocation, align);
 155                        break;
 156                case R_M32R_SDA16_RELA:
 157                case R_M32R_LO16_RELA:
 158                        COPY_UNALIGNED_WORD (*location, value, align);
 159                        relocation = relocation & 0xffff;
 160                        /* RELA must has 0 at relocation field. */
 161                        value += relocation;
 162                        COPY_UNALIGNED_WORD (value, *location, align);
 163                        break;
 164                case R_M32R_24_RELA:
 165                        COPY_UNALIGNED_WORD (*location, value, align);
 166                        relocation = relocation & 0xffffff;
 167                        /* RELA must has 0 at relocation field. */
 168                        value += relocation;
 169                        COPY_UNALIGNED_WORD (value, *location, align);
 170                        break;
 171                case R_M32R_18_PCREL_RELA:
 172                        relocation = (relocation - (Elf32_Addr) location);
 173                        if (relocation < -0x20000 || 0x1fffc < relocation)
 174                                {
 175                                        printk(KERN_ERR "module %s: relocation overflow: %u\n",
 176                                        me->name, relocation);
 177                                        return -ENOEXEC;
 178                                }
 179                        COPY_UNALIGNED_WORD (*location, value, align);
 180                        if (value & 0xffff)
 181                                {
 182                                        /* RELA must has 0 at relocation field. */
 183                                        printk(KERN_ERR "module %s: illegal relocation field: %u\n",
 184                                        me->name, value);
 185                                        return -ENOEXEC;
 186                                }
 187                        relocation = (relocation >> 2) & 0xffff;
 188                        value += relocation;
 189                        COPY_UNALIGNED_WORD (value, *location, align);
 190                        break;
 191                case R_M32R_10_PCREL_RELA:
 192                        hlocation = (unsigned short *)location;
 193                        relocation = (relocation - (Elf32_Addr) location);
 194                        COPY_UNALIGNED_HWORD (*hlocation, hvalue, align);
 195                        svalue = (int)hvalue;
 196                        svalue = (signed char)svalue << 2;
 197                        relocation += svalue;
 198                        relocation = (relocation >> 2) & 0xff;
 199                        hvalue = hvalue & 0xff00;
 200                        hvalue += relocation;
 201                        COPY_UNALIGNED_HWORD (hvalue, *hlocation, align);
 202                        break;
 203                case R_M32R_26_PCREL_RELA:
 204                        relocation = (relocation - (Elf32_Addr) location);
 205                        if (relocation < -0x2000000 || 0x1fffffc < relocation)
 206                                {
 207                                        printk(KERN_ERR "module %s: relocation overflow: %u\n",
 208                                        me->name, relocation);
 209                                        return -ENOEXEC;
 210                                }
 211                        COPY_UNALIGNED_WORD (*location, value, align);
 212                        if (value & 0xffffff)
 213                                {
 214                                        /* RELA must has 0 at relocation field. */
 215                                        printk(KERN_ERR "module %s: illegal relocation field: %u\n",
 216                                        me->name, value);
 217                                        return -ENOEXEC;
 218                                }
 219                        relocation = (relocation >> 2) & 0xffffff;
 220                        value += relocation;
 221                        COPY_UNALIGNED_WORD (value, *location, align);
 222                        break;
 223                default:
 224                        printk(KERN_ERR "module %s: Unknown relocation: %u\n",
 225                               me->name, ELF32_R_TYPE(rel[i].r_info));
 226                        return -ENOEXEC;
 227                }
 228        }
 229        return 0;
 230}
 231
 232int apply_relocate(Elf32_Shdr *sechdrs,
 233                       const char *strtab,
 234                       unsigned int symindex,
 235                       unsigned int relsec,
 236                       struct module *me)
 237{
 238#if 0
 239        printk(KERN_ERR "module %s: REL RELOCATION unsupported\n",
 240               me->name);
 241        return -ENOEXEC;
 242#endif
 243        return 0;
 244
 245}
 246
 247int module_finalize(const Elf_Ehdr *hdr,
 248                    const Elf_Shdr *sechdrs,
 249                    struct module *me)
 250{
 251        return 0;
 252}
 253
 254void module_arch_cleanup(struct module *mod)
 255{
 256}
 257