modules: add default loader hook implementations

The module loader code allows architectures to hook into the code by
providing a small number of entry points that each arch must implement.
This patch provides __weakly linked generic implementations of these
entry points for architectures that don't need to do anything special.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Jonas Bonn 2011-06-30 21:22:11 +02:00 committed by Rusty Russell
parent 81c7413650
commit 74e08fcf7b
2 changed files with 55 additions and 1 deletions

View File

@ -5,7 +5,12 @@
#include <linux/module.h>
#include <linux/elf.h>
/* These must be implemented by the specific architecture */
/* These may be implemented by architectures that need to hook into the
* module loader code. Architectures that don't need to do anything special
* can just rely on the 'weak' default hooks defined in kernel/module.c.
* Note, however, that at least one of apply_relocate or apply_relocate_add
* must be implemented by each architecture.
*/
/* Adjust arch-specific sections. Return 0 on success. */
int module_frob_arch_sections(Elf_Ehdr *hdr,

View File

@ -1697,6 +1697,15 @@ static void unset_module_core_ro_nx(struct module *mod) { }
static void unset_module_init_ro_nx(struct module *mod) { }
#endif
void __weak module_free(struct module *mod, void *module_region)
{
vfree(module_region);
}
void __weak module_arch_cleanup(struct module *mod)
{
}
/* Free a module, remove from lists, etc. */
static void free_module(struct module *mod)
{
@ -1851,6 +1860,26 @@ static int simplify_symbols(struct module *mod, const struct load_info *info)
return ret;
}
int __weak apply_relocate(Elf_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
pr_err("module %s: REL relocation unsupported\n", me->name);
return -ENOEXEC;
}
int __weak apply_relocate_add(Elf_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
pr_err("module %s: RELA relocation unsupported\n", me->name);
return -ENOEXEC;
}
static int apply_relocations(struct module *mod, const struct load_info *info)
{
unsigned int i;
@ -2235,6 +2264,11 @@ static void dynamic_debug_remove(struct _ddebug *debug)
ddebug_remove_module(debug->modname);
}
void * __weak module_alloc(unsigned long size)
{
return size == 0 ? NULL : vmalloc_exec(size);
}
static void *module_alloc_update_bounds(unsigned long size)
{
void *ret = module_alloc(size);
@ -2645,6 +2679,14 @@ static void flush_module_icache(const struct module *mod)
set_fs(old_fs);
}
int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
Elf_Shdr *sechdrs,
char *secstrings,
struct module *mod)
{
return 0;
}
static struct module *layout_and_allocate(struct load_info *info)
{
/* Module within temporary copy. */
@ -2716,6 +2758,13 @@ static void module_deallocate(struct module *mod, struct load_info *info)
module_free(mod, mod->module_core);
}
int __weak module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
{
return 0;
}
static int post_relocation(struct module *mod, const struct load_info *info)
{
/* Sort exception table now relocations are done. */