ARM: module: clean up handling of ELF unwind tables
There's no need to keep pointers to the ELF sections available while
the module is loaded - we only need the section pointers while we're
finding and registering the unwind tables, which can all be done during
the finalize stage of loading.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/module.h b/arch/arm/include/asm/module.h
index cbb0bc2..12c8e68 100644
--- a/arch/arm/include/asm/module.h
+++ b/arch/arm/include/asm/module.h
@@ -8,11 +8,6 @@
struct unwind_table;
#ifdef CONFIG_ARM_UNWIND
-struct arm_unwind_mapping {
- Elf_Shdr *unw_sec;
- Elf_Shdr *sec_text;
- struct unwind_table *unwind;
-};
enum {
ARM_SEC_INIT,
ARM_SEC_DEVINIT,
@@ -21,14 +16,14 @@
ARM_SEC_DEVEXIT,
ARM_SEC_MAX,
};
-struct mod_arch_specific {
- struct arm_unwind_mapping map[ARM_SEC_MAX];
-};
-#else
-struct mod_arch_specific {
-};
#endif
+struct mod_arch_specific {
+#ifdef CONFIG_ARM_UNWIND
+ struct unwind_table *unwind[ARM_SEC_MAX];
+#endif
+};
+
/*
* Include the ARM architecture version.
*/
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index d9bd786..f9937c4 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -67,35 +67,6 @@
char *secstrings,
struct module *mod)
{
-#ifdef CONFIG_ARM_UNWIND
- Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum;
- struct arm_unwind_mapping *maps = mod->arch.map;
-
- for (s = sechdrs; s < sechdrs_end; s++) {
- char const *secname = secstrings + s->sh_name;
-
- if (strcmp(".ARM.exidx.init.text", secname) == 0)
- maps[ARM_SEC_INIT].unw_sec = s;
- else if (strcmp(".ARM.exidx.devinit.text", secname) == 0)
- maps[ARM_SEC_DEVINIT].unw_sec = s;
- else if (strcmp(".ARM.exidx", secname) == 0)
- maps[ARM_SEC_CORE].unw_sec = s;
- else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
- maps[ARM_SEC_EXIT].unw_sec = s;
- else if (strcmp(".ARM.exidx.devexit.text", secname) == 0)
- maps[ARM_SEC_DEVEXIT].unw_sec = s;
- else if (strcmp(".init.text", secname) == 0)
- maps[ARM_SEC_INIT].sec_text = s;
- else if (strcmp(".devinit.text", secname) == 0)
- maps[ARM_SEC_DEVINIT].sec_text = s;
- else if (strcmp(".text", secname) == 0)
- maps[ARM_SEC_CORE].sec_text = s;
- else if (strcmp(".exit.text", secname) == 0)
- maps[ARM_SEC_EXIT].sec_text = s;
- else if (strcmp(".devexit.text", secname) == 0)
- maps[ARM_SEC_DEVEXIT].sec_text = s;
- }
-#endif
return 0;
}
@@ -300,41 +271,66 @@
return -ENOEXEC;
}
+struct mod_unwind_map {
+ const Elf_Shdr *unw_sec;
+ const Elf_Shdr *txt_sec;
+};
+
+int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
+ struct module *mod)
+{
#ifdef CONFIG_ARM_UNWIND
-static void register_unwind_tables(struct module *mod)
-{
+ const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+ const Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum;
+ struct mod_unwind_map maps[ARM_SEC_MAX];
int i;
- for (i = 0; i < ARM_SEC_MAX; ++i) {
- struct arm_unwind_mapping *map = &mod->arch.map[i];
- if (map->unw_sec && map->sec_text)
- map->unwind = unwind_table_add(map->unw_sec->sh_addr,
- map->unw_sec->sh_size,
- map->sec_text->sh_addr,
- map->sec_text->sh_size);
+
+ memset(maps, 0, sizeof(maps));
+
+ for (s = sechdrs; s < sechdrs_end; s++) {
+ const char *secname = secstrs + s->sh_name;
+
+ if (strcmp(".ARM.exidx.init.text", secname) == 0)
+ maps[ARM_SEC_INIT].unw_sec = s;
+ else if (strcmp(".ARM.exidx.devinit.text", secname) == 0)
+ maps[ARM_SEC_DEVINIT].unw_sec = s;
+ else if (strcmp(".ARM.exidx", secname) == 0)
+ maps[ARM_SEC_CORE].unw_sec = s;
+ else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
+ maps[ARM_SEC_EXIT].unw_sec = s;
+ else if (strcmp(".ARM.exidx.devexit.text", secname) == 0)
+ maps[ARM_SEC_DEVEXIT].unw_sec = s;
+ else if (strcmp(".init.text", secname) == 0)
+ maps[ARM_SEC_INIT].txt_sec = s;
+ else if (strcmp(".devinit.text", secname) == 0)
+ maps[ARM_SEC_DEVINIT].txt_sec = s;
+ else if (strcmp(".text", secname) == 0)
+ maps[ARM_SEC_CORE].txt_sec = s;
+ else if (strcmp(".exit.text", secname) == 0)
+ maps[ARM_SEC_EXIT].txt_sec = s;
+ else if (strcmp(".devexit.text", secname) == 0)
+ maps[ARM_SEC_DEVEXIT].txt_sec = s;
}
-}
-static void unregister_unwind_tables(struct module *mod)
-{
- int i = ARM_SEC_MAX;
- while (--i >= 0)
- unwind_table_del(mod->arch.map[i].unwind);
-}
-#else
-static inline void register_unwind_tables(struct module *mod) { }
-static inline void unregister_unwind_tables(struct module *mod) { }
+ for (i = 0; i < ARM_SEC_MAX; i++)
+ if (maps[i].unw_sec && maps[i].txt_sec)
+ mod->arch.unwind[i] =
+ unwind_table_add(maps[i].unw_sec->sh_addr,
+ maps[i].unw_sec->sh_size,
+ maps[i].txt_sec->sh_addr,
+ maps[i].txt_sec->sh_size);
#endif
-
-int
-module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
- struct module *module)
-{
- register_unwind_tables(module);
return 0;
}
void
module_arch_cleanup(struct module *mod)
{
- unregister_unwind_tables(mod);
+#ifdef CONFIG_ARM_UNWIND
+ int i;
+
+ for (i = 0; i < ARM_SEC_MAX; i++)
+ if (mod->arch.unwind[i])
+ unwind_table_del(mod->arch.unwind[i]);
+#endif
}