arch/sparc/kernel/module.c

   1 /* Kernel module help for sparc32.
   2  *
   3  * Copyright (C) 2001 Rusty Russell.
   4  * Copyright (C) 2002 David S. Miller.
   5  */
   6
   7 #include <linux/moduleloader.h>
   8 #include <linux/kernel.h>
   9 #include <linux/elf.h>
  10 #include <linux/vmalloc.h>
  11 #include <linux/fs.h>
  12 #include <linux/string.h>
  13 #include <linux/ctype.h>
  14
  15 void *module_alloc(unsigned long size)
  16 {
  17         void *ret;
  18
  19         /* We handle the zero case fine, unlike vmalloc */
  20         if (size == 0)
  21                 return NULL;
  22
  23         ret = vmalloc(size);
  24         if (!ret)
  25                 ret = ERR_PTR(-ENOMEM);
  26         else
  27                 memset(ret, 0, size);
  28
  29         return ret;
  30 }
  31
  32 /* Free memory returned from module_core_alloc/module_init_alloc */
  33 void module_free(struct module *mod, void *module_region)
  34 {
  35         vfree(module_region);
  36         /* FIXME: If module_region == mod->init_region, trim exception
  37            table entries. */
  38 }
  39
  40 /* Make generic code ignore STT_REGISTER dummy undefined symbols,
  41  * and replace references to .func with _Func
  42  */
  43 int module_frob_arch_sections(Elf_Ehdr *hdr,
  44                               Elf_Shdr *sechdrs,
  45                               char *secstrings,
  46                               struct module *mod)
  47 {
  48         unsigned int symidx;
  49         Elf32_Sym *sym;
  50         char *strtab;
  51         int i;
  52
  53         for (symidx = 0; sechdrs[symidx].sh_type != SHT_SYMTAB; symidx++) {
  54                 if (symidx == hdr->e_shnum-1) {
  55                         printk("%s: no symtab found.\n", mod->name);
  56                         return -ENOEXEC;
  57                 }
  58         }
  59         sym = (Elf32_Sym *)sechdrs[symidx].sh_addr;
  60         strtab = (char *)sechdrs[sechdrs[symidx].sh_link].sh_addr;
  61
  62         for (i = 1; i < sechdrs[symidx].sh_size / sizeof(Elf_Sym); i++) {
  63                 if (sym[i].st_shndx == SHN_UNDEF) {
  64                         if (ELF32_ST_TYPE(sym[i].st_info) == STT_REGISTER)
  65                                 sym[i].st_shndx = SHN_ABS;
  66                         else {
  67                                 char *name = strtab + sym[i].st_name;
  68                                 if (name[0] == '.') {
  69                                         name[0] = '_';
  70                                         name[1] = toupper(name[1]);
  71                                 }
  72                         }
  73                 }
  74         }
  75         return 0;
  76 }
  77
  78 int apply_relocate(Elf32_Shdr *sechdrs,
  79                    const char *strtab,
  80                    unsigned int symindex,
  81                    unsigned int relsec,
  82                    struct module *me)
  83 {
  84         printk(KERN_ERR "module %s: non-ADD RELOCATION unsupported\n",
  85                me->name);
  86         return -ENOEXEC;
  87 }
  88
  89 int apply_relocate_add(Elf32_Shdr *sechdrs,
  90                        const char *strtab,
  91                        unsigned int symindex,
  92                        unsigned int relsec,
  93                        struct module *me)
  94 {
  95         unsigned int i;
  96         Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
  97         Elf32_Sym *sym;
  98         u8 *location;
  99         u32 *loc32;
 100
 101         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
 102                 Elf32_Addr v;
 103
 104                 /* This is where to make the change */
 105                 location = (u8 *)sechdrs[sechdrs[relsec].sh_info].sh_addr
 106                         + rel[i].r_offset;
 107                 loc32 = (u32 *) location;
 108                 /* This is the symbol it is referring to.  Note that all
 109                    undefined symbols have been resolved.  */
 110                 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
 111                         + ELF32_R_SYM(rel[i].r_info);
 112                 v = sym->st_value + rel[i].r_addend;
 113
 114                 switch (ELF32_R_TYPE(rel[i].r_info)) {
 115                 case R_SPARC_32:
 116                         location[0] = v >> 24;
 117                         location[1] = v >> 16;
 118                         location[2] = v >>  8;
 119                         location[3] = v >>  0;
 120                         break;
 121
 122                 case R_SPARC_WDISP30:
 123                         v -= (Elf32_Addr) location;
 124                         *loc32 = (*loc32 & ~0x3fffffff) |
 125                                 ((v >> 2) & 0x3fffffff);
 126                         break;
 127
 128                 case R_SPARC_WDISP22:
 129                         v -= (Elf32_Addr) location;
 130                         *loc32 = (*loc32 & ~0x3fffff) |
 131                                 ((v >> 2) & 0x3fffff);
 132                         break;
 133
 134                 case R_SPARC_LO10:
 135                         *loc32 = (*loc32 & ~0x3ff) | (v & 0x3ff);
 136                         break;
 137
 138                 case R_SPARC_HI22:
 139                         *loc32 = (*loc32 & ~0x3fffff) |
 140                                 ((v >> 10) & 0x3fffff);
 141                         break;
 142
 143                 default:
 144                         printk(KERN_ERR "module %s: Unknown relocation: %x\n",
 145                                me->name,
 146                                (int) (ELF32_R_TYPE(rel[i].r_info) & 0xff));
 147                         return -ENOEXEC;
 148                 };
 149         }
 150         return 0;
 151 }
 152
 153 int module_finalize(const Elf_Ehdr *hdr,
 154                     const Elf_Shdr *sechdrs,
 155                     struct module *me)
 156 {
 157         return 0;
 158 }
 159
 160 void module_arch_cleanup(struct module *mod)
 161 {
 162 }