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         area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
  31         if (!area)
  32                 return NULL;
  33
  34         return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
  35 }
  36
  37 int
  38 apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
  39                unsigned int relindex, struct module *module)
  40 {
  41         Elf32_Shdr *symsec = sechdrs + symindex;
  42         Elf32_Shdr *relsec = sechdrs + relindex;
  43         Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
  44         Elf32_Rel *rel = (void *)relsec->sh_addr;
  45         unsigned int i;
  46
  47         for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
  48                 unsigned long loc;
  49                 Elf32_Sym *sym;
  50                 s32 offset;
  51
  52                 offset = ELF32_R_SYM(rel->r_info);
  53                 if (offset < 0 || offset >
  54                                 (symsec->sh_size / sizeof(Elf32_Sym))) {
  55                         printk(KERN_ERR "%s: bad relocation, "
  56                                         "section %d reloc %d\n",
  57                                         module->name, relindex, i);
  58                         return -ENOEXEC;
  59                 }
  60
  61                 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
  62
  63                 if (rel->r_offset < 0 || rel->r_offset >
  64                                 dstsec->sh_size - sizeof(u32)) {
  65                         printk(KERN_ERR "%s: out of bounds relocation, "
  66                                 "section %d reloc %d offset %d size %d\n",
  67                                 module->name, relindex, i, rel->r_offset,
  68                                 dstsec->sh_size);
  69                         return -ENOEXEC;
  70                 }
  71
  72                 loc = dstsec->sh_addr + rel->r_offset;
  73
  74                 switch (ELF32_R_TYPE(rel->r_info)) {
  75                 case R_UNICORE_NONE:
  76                         /* ignore */
  77                         break;
  78
  79                 case R_UNICORE_ABS32:
  80                         *(u32 *)loc += sym->st_value;
  81                         break;
  82
  83                 case R_UNICORE_PC24:
  84                 case R_UNICORE_CALL:
  85                 case R_UNICORE_JUMP24:
  86                         offset = (*(u32 *)loc & 0x00ffffff) << 2;
  87                         if (offset & 0x02000000)
  88                                 offset -= 0x04000000;
  89
  90                         offset += sym->st_value - loc;
  91                         if (offset & 3 ||
  92                             offset <= (s32)0xfe000000 ||
  93                             offset >= (s32)0x02000000) {
  94                                 printk(KERN_ERR
  95                                        "%s: relocation out of range, section "
  96                                        "%d reloc %d sym '%s'\n", module->name,
  97                                        relindex, i, strtab + sym->st_name);
  98                                 return -ENOEXEC;
  99                         }
 100
 101                         offset >>= 2;
 102
 103                         *(u32 *)loc &= 0xff000000;
 104                         *(u32 *)loc |= offset & 0x00ffffff;
 105                         break;
 106
 107                 default:
 108                         printk(KERN_ERR "%s: unknown relocation: %u\n",
 109                                module->name, ELF32_R_TYPE(rel->r_info));
 110                         return -ENOEXEC;
 111                 }
 112         }
 113         return 0;
 114 }