arch/powerpc/kernel/module.c

   1 /*  Kernel module help for powerpc.
   2     Copyright (C) 2001, 2003 Rusty Russell IBM Corporation.
   3     Copyright (C) 2008 Freescale Semiconductor, Inc.
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 */
  19 #include <linux/module.h>
  20 #include <linux/elf.h>
  21 #include <linux/moduleloader.h>
  22 #include <linux/err.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/bug.h>
  25 #include <asm/module.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/firmware.h>
  28 #include <linux/sort.h>
  29
  30 #include "setup.h"
  31
  32 LIST_HEAD(module_bug_list);
  33
  34 void *module_alloc(unsigned long size)
  35 {
  36         if (size == 0)
  37                 return NULL;
  38
  39         return vmalloc_exec(size);
  40 }
  41
  42 /* Free memory returned from module_alloc */
  43 void module_free(struct module *mod, void *module_region)
  44 {
  45         vfree(module_region);
  46         /* FIXME: If module_region == mod->init_region, trim exception
  47            table entries. */
  48 }
  49
  50 static const Elf_Shdr *find_section(const Elf_Ehdr *hdr,
  51                                     const Elf_Shdr *sechdrs,
  52                                     const char *name)
  53 {
  54         char *secstrings;
  55         unsigned int i;
  56
  57         secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
  58         for (i = 1; i < hdr->e_shnum; i++)
  59                 if (strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
  60                         return &sechdrs[i];
  61         return NULL;
  62 }
  63
  64 int module_finalize(const Elf_Ehdr *hdr,
  65                 const Elf_Shdr *sechdrs, struct module *me)
  66 {
  67         const Elf_Shdr *sect;
  68         int err;
  69
  70         err = module_bug_finalize(hdr, sechdrs, me);
  71         if (err)
  72                 return err;
  73
  74         /* Apply feature fixups */
  75         sect = find_section(hdr, sechdrs, "__ftr_fixup");
  76         if (sect != NULL)
  77                 do_feature_fixups(cur_cpu_spec->cpu_features,
  78                                   (void *)sect->sh_addr,
  79                                   (void *)sect->sh_addr + sect->sh_size);
  80
  81 #ifdef CONFIG_PPC64
  82         sect = find_section(hdr, sechdrs, "__fw_ftr_fixup");
  83         if (sect != NULL)
  84                 do_feature_fixups(powerpc_firmware_features,
  85                                   (void *)sect->sh_addr,
  86                                   (void *)sect->sh_addr + sect->sh_size);
  87 #endif
  88
  89         sect = find_section(hdr, sechdrs, "__lwsync_fixup");
  90         if (sect != NULL)
  91                 do_lwsync_fixups(cur_cpu_spec->cpu_features,
  92                                  (void *)sect->sh_addr,
  93                                  (void *)sect->sh_addr + sect->sh_size);
  94
  95         return 0;
  96 }
  97
  98 void module_arch_cleanup(struct module *mod)
  99 {
 100         module_bug_cleanup(mod);
 101 }
 102
 103 struct bug_entry *module_find_bug(unsigned long bugaddr)
 104 {
 105         struct mod_arch_specific *mod;
 106         unsigned int i;
 107         struct bug_entry *bug;
 108
 109         list_for_each_entry(mod, &module_bug_list, bug_list) {
 110                 bug = mod->bug_table;
 111                 for (i = 0; i < mod->num_bugs; ++i, ++bug)
 112                         if (bugaddr == bug->bug_addr)
 113                                 return bug;
 114         }
 115         return NULL;
 116 }