arch/h8300/kernel/module.c

   1 #include <linux/moduleloader.h>
   2 #include <linux/elf.h>
   3 #include <linux/vmalloc.h>
   4 #include <linux/fs.h>
   5 #include <linux/string.h>
   6 #include <linux/kernel.h>
   7
   8 #if 0
   9 #define DEBUGP printk
  10 #else
  11 #define DEBUGP(fmt...)
  12 #endif
  13
  14 int apply_relocate_add(Elf32_Shdr *sechdrs,
  15                        const char *strtab,
  16                        unsigned int symindex,
  17                        unsigned int relsec,
  18                        struct module *me)
  19 {
  20         unsigned int i;
  21         Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
  22
  23         DEBUGP("Applying relocate section %u to %u\n", relsec,
  24                sechdrs[relsec].sh_info);
  25         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
  26                 /* This is where to make the change */
  27                 uint32_t *loc = (uint32_t *)(sechdrs[sechdrs[relsec].sh_info].sh_addr
  28                                              + rela[i].r_offset);
  29                 /* This is the symbol it is referring to.  Note that all
  30                    undefined symbols have been resolved.  */
  31                 Elf32_Sym *sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
  32                         + ELF32_R_SYM(rela[i].r_info);
  33                 uint32_t v = sym->st_value + rela[i].r_addend;
  34
  35                 switch (ELF32_R_TYPE(rela[i].r_info)) {
  36                 case R_H8_DIR24R8:
  37                         loc = (uint32_t *)((uint32_t)loc - 1);
  38                         *loc = (*loc & 0xff000000) | ((*loc & 0xffffff) + v);
  39                         break;
  40                 case R_H8_DIR24A8:
  41                         if (ELF32_R_SYM(rela[i].r_info))
  42                                 *loc += v;
  43                         break;
  44                 case R_H8_DIR32:
  45                 case R_H8_DIR32A16:
  46                         *loc += v;
  47                         break;
  48                 case R_H8_PCREL16:
  49                         v -= (unsigned long)loc + 2;
  50                         if ((Elf32_Sword)v > 0x7fff ||
  51                             (Elf32_Sword)v < -(Elf32_Sword)0x8000)
  52                                 goto overflow;
  53                         else
  54                                 *(unsigned short *)loc = v;
  55                         break;
  56                 case R_H8_PCREL8:
  57                         v -= (unsigned long)loc + 1;
  58                         if ((Elf32_Sword)v > 0x7f ||
  59                             (Elf32_Sword)v < -(Elf32_Sword)0x80)
  60                                 goto overflow;
  61                         else
  62                                 *(unsigned char *)loc = v;
  63                         break;
  64                 default:
  65                         printk(KERN_ERR "module %s: Unknown relocation: %u\n",
  66                                me->name, ELF32_R_TYPE(rela[i].r_info));
  67                         return -ENOEXEC;
  68                 }
  69         }
  70         return 0;
  71  overflow:
  72         printk(KERN_ERR "module %s: relocation offset overflow: %08x\n",
  73                me->name, rela[i].r_offset);
  74         return -ENOEXEC;
  75 }