arch/unicore32/kernel/module.c

   1 /*
   2  * linux/arch/unicore32/kernel/module.c
   3  *
   4  * Code specific to PKUnity SoC and UniCore ISA
   5  *
   6  * Copyright (C) 2001-2010 GUAN Xue-tao
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12 #include <linux/module.h>
  13 #include <linux/moduleloader.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mm.h>
  16 #include <linux/elf.h>
  17 #include <linux/vmalloc.h>
  18 #include <linux/fs.h>
  19 #include <linux/string.h>
  20 #include <linux/gfp.h>
  21
  22 #include <asm/pgtable.h>
  23 #include <asm/sections.h>
  24
  25 void *module_alloc(unsigned long size)
  26 {
  27         struct vm_struct *area;
  28
  29         size = PAGE_ALIGN(size);
  30         if (!size)
  31                 return NULL;
  32
  33         area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
  34         if (!area)
  35                 return NULL;
  36
  37         return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
  38 }
  39
  40 int
  41 apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
  42                unsigned int relindex, struct module *module)
  43 {
  44         Elf32_Shdr *symsec = sechdrs + symindex;
  45         Elf32_Shdr *relsec = sechdrs + relindex;
  46         Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
  47         Elf32_Rel *rel = (void *)relsec->sh_addr;
  48         unsigned int i;
  49
  50         for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
  51                 unsigned long loc;
  52                 Elf32_Sym *sym;
  53                 s32 offset;
  54
  55                 offset = ELF32_R_SYM(rel->r_info);
  56                 if (offset < 0 || offset >
  57                                 (symsec->sh_size / sizeof(Elf32_Sym))) {
  58                         printk(KERN_ERR "%s: bad relocation, "
  59                                         "section %d reloc %d\n",
  60                                         module->name, relindex, i);
  61                         return -ENOEXEC;
  62                 }
  63
  64                 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
  65
  66                 if (rel->r_offset < 0 || rel->r_offset >
  67                                 dstsec->sh_size - sizeof(u32)) {
  68                         printk(KERN_ERR "%s: out of bounds relocation, "
  69                                 "section %d reloc %d offset %d size %d\n",
  70                                 module->name, relindex, i, rel->r_offset,
  71                                 dstsec->sh_size);
  72                         return -ENOEXEC;
  73                 }
  74
  75                 loc = dstsec->sh_addr + rel->r_offset;
  76
  77                 switch (ELF32_R_TYPE(rel->r_info)) {
  78                 case R_UNICORE_NONE:
  79                         /* ignore */
  80                         break;
  81
  82                 case R_UNICORE_ABS32:
  83                         *(u32 *)loc += sym->st_value;
  84                         break;
  85
  86                 case R_UNICORE_PC24:
  87                 case R_UNICORE_CALL:
  88                 case R_UNICORE_JUMP24:
  89                         offset = (*(u32 *)loc & 0x00ffffff) << 2;
  90                         if (offset & 0x02000000)
  91                                 offset -= 0x04000000;
  92
  93                         offset += sym->st_value - loc;
  94                         if (offset & 3 ||
  95                             offset <= (s32)0xfe000000 ||
  96                             offset >= (s32)0x02000000) {
  97                                 printk(KERN_ERR
  98                                        "%s: relocation out of range, section "
  99                                        "%d reloc %d sym '%s'\n", module->name,
 100                                        relindex, i, strtab + sym->st_name);
 101                                 return -ENOEXEC;
 102                         }
 103
 104                         offset >>= 2;
 105
 106                         *(u32 *)loc &= 0xff000000;
 107                         *(u32 *)loc |= offset & 0x00ffffff;
 108                         break;
 109
 110                 default:
 111                         printk(KERN_ERR "%s: unknown relocation: %u\n",
 112                                module->name, ELF32_R_TYPE(rel->r_info));
 113                         return -ENOEXEC;
 114                 }
 115         }
 116         return 0;
 117 }