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
  14 void *module_alloc(unsigned long size)
  15 {
  16         void *ret;
  17
  18         /* We handle the zero case fine, unlike vmalloc */
  19         if (size == 0)
  20                 return NULL;
  21
  22         ret = vmalloc(size);
  23         if (!ret)
  24                 ret = ERR_PTR(-ENOMEM);
  25         else
  26                 memset(ret, 0, size);
  27
  28         return ret;
  29 }
  30
  31 /* Free memory returned from module_core_alloc/module_init_alloc */
  32 void module_free(struct module *mod, void *module_region)
  33 {
  34         vfree(module_region);
  35         /* FIXME: If module_region == mod->init_region, trim exception
  36            table entries. */
  37 }
  38
  39 /* Make generic code ignore STT_REGISTER dummy undefined symbols,
  40  * and replace references to .func with func as in ppc64's dedotify.
  41  */
  42 int module_frob_arch_sections(Elf_Ehdr *hdr,
  43                               Elf_Shdr *sechdrs,
  44                               char *secstrings,
  45                               struct module *mod)
  46 {
  47         unsigned int symidx;
  48         Elf32_Sym *sym;
  49         char *strtab;
  50         int i;
  51
  52         for (symidx = 0; sechdrs[symidx].sh_type != SHT_SYMTAB; symidx++) {
  53                 if (symidx == hdr->e_shnum-1) {
  54                         printk("%s: no symtab found.\n", mod->name);
  55                         return -ENOEXEC;
  56                 }
  57         }
  58         sym = (Elf32_Sym *)sechdrs[symidx].sh_addr;
  59         strtab = (char *)sechdrs[sechdrs[symidx].sh_link].sh_addr;
  60
  61         for (i = 1; i < sechdrs[symidx].sh_size / sizeof(Elf_Sym); i++) {
  62                 if (sym[i].st_shndx == SHN_UNDEF) {
  63                         if (ELF32_ST_TYPE(sym[i].st_info) == STT_REGISTER)
  64                                 sym[i].st_shndx = SHN_ABS;
  65                         else {
  66                                 char *name = strtab + sym[i].st_name;
  67                                 if (name[0] == '.')
  68                                         memmove(name, name+1, strlen(name));
  69                         }
  70                 }
  71         }
  72         return 0;
  73 }
  74
  75 int apply_relocate(Elf32_Shdr *sechdrs,
  76                    const char *strtab,
  77                    unsigned int symindex,
  78                    unsigned int relsec,
  79                    struct module *me)
  80 {
  81         printk(KERN_ERR "module %s: non-ADD RELOCATION unsupported\n",
  82                me->name);
  83         return -ENOEXEC;
  84 }
  85
  86 int apply_relocate_add(Elf32_Shdr *sechdrs,
  87                        const char *strtab,
  88                        unsigned int symindex,
  89                        unsigned int relsec,
  90                        struct module *me)
  91 {
  92         unsigned int i;
  93         Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
  94         Elf32_Sym *sym;
  95         u8 *location;
  96         u32 *loc32;
  97
  98         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
  99                 Elf32_Addr v;
 100
 101                 /* This is where to make the change */
 102                 location = (u8 *)sechdrs[sechdrs[relsec].sh_info].sh_addr
 103                         + rel[i].r_offset;
 104                 loc32 = (u32 *) location;
 105                 /* This is the symbol it is referring to.  Note that all
 106                    undefined symbols have been resolved.  */
 107                 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
 108                         + ELF32_R_SYM(rel[i].r_info);
 109                 v = sym->st_value + rel[i].r_addend;
 110
 111                 switch (ELF32_R_TYPE(rel[i].r_info)) {
 112                 case R_SPARC_32:
 113                         location[0] = v >> 24;
 114                         location[1] = v >> 16;
 115                         location[2] = v >>  8;
 116                         location[3] = v >>  0;
 117                         break;
 118
 119                 case R_SPARC_WDISP30:
 120                         v -= (Elf32_Addr) location;
 121                         *loc32 = (*loc32 & ~0x3fffffff) |
 122                                 ((v >> 2) & 0x3fffffff);
 123                         break;
 124
 125                 case R_SPARC_WDISP22:
 126                         v -= (Elf32_Addr) location;
 127                         *loc32 = (*loc32 & ~0x3fffff) |
 128                                 ((v >> 2) & 0x3fffff);
 129                         break;
 130
 131                 case R_SPARC_LO10:
 132                         *loc32 = (*loc32 & ~0x3ff) | (v & 0x3ff);
 133                         break;
 134
 135                 case R_SPARC_HI22:
 136                         *loc32 = (*loc32 & ~0x3fffff) |
 137                                 ((v >> 10) & 0x3fffff);
 138                         break;
 139
 140                 default:
 141                         printk(KERN_ERR "module %s: Unknown relocation: %x\n",
 142                                me->name,
 143                                (int) (ELF32_R_TYPE(rel[i].r_info) & 0xff));
 144                         return -ENOEXEC;
 145                 };
 146         }
 147         return 0;
 148 }
 149
 150 int module_finalize(const Elf_Ehdr *hdr,
 151                     const Elf_Shdr *sechdrs,
 152                     struct module *me)
 153 {
 154         return 0;
 155 }
 156
 157 void module_arch_cleanup(struct module *mod)
 158 {
 159 }