module_arch_freeing_init(): new hook for archs before module->module_init freed.

Archs have been abusing module_free() to clean up their arch-specific
allocations.  Since module_free() is also (ab)used by BPF and trace code,
let's keep it to simple allocations, and provide a hook called before
that.

This means that avr32, ia64, parisc and s390 no longer need to implement
their own module_free() at all.  avr32 doesn't need module_finalize()
either.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
This commit is contained in:
Rusty Russell 2015-01-20 09:07:04 +10:30
parent c772be5231
commit d453cded05
7 changed files with 17 additions and 29 deletions

View File

@ -19,12 +19,10 @@
#include <linux/moduleloader.h>
#include <linux/vmalloc.h>
void module_free(struct module *mod, void *module_region)
void module_arch_freeing_init(struct module *mod)
{
vfree(mod->arch.syminfo);
mod->arch.syminfo = NULL;
vfree(module_region);
}
static inline int check_rela(Elf32_Rela *rela, struct module *module,
@ -291,12 +289,3 @@ int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
return ret;
}
int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
struct module *module)
{
vfree(module->arch.syminfo);
module->arch.syminfo = NULL;
return 0;
}

View File

@ -305,14 +305,12 @@ plt_target (struct plt_entry *plt)
#endif /* !USE_BRL */
void
module_free (struct module *mod, void *module_region)
module_arch_freeing_init (struct module *mod)
{
if (mod && mod->arch.init_unw_table &&
module_region == mod->module_init) {
if (mod->arch.init_unw_table) {
unw_remove_unwind_table(mod->arch.init_unw_table);
mod->arch.init_unw_table = NULL;
}
vfree(module_region);
}
/* Have we already seen one of these relocations? */

View File

@ -298,14 +298,10 @@ static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
}
#endif
/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
void module_arch_freeing_init(struct module *mod)
{
kfree(mod->arch.section);
mod->arch.section = NULL;
vfree(module_region);
}
/* Additional bytes needed in front of individual sections */

View File

@ -55,14 +55,10 @@ void *module_alloc(unsigned long size)
}
#endif
/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
void module_arch_freeing_init(struct module *mod)
{
if (mod) {
vfree(mod->arch.syminfo);
mod->arch.syminfo = NULL;
}
vfree(module_region);
vfree(mod->arch.syminfo);
mod->arch.syminfo = NULL;
}
static void check_rela(Elf_Rela *rela, struct module *me)

View File

@ -83,7 +83,7 @@ void module_free(struct module *mod, void *module_region)
0, 0, 0, NULL, NULL, 0);
/*
* FIXME: If module_region == mod->module_init, trim exception
* FIXME: Add module_arch_freeing_init to trim exception
* table entries.
*/
}

View File

@ -82,4 +82,6 @@ int module_finalize(const Elf_Ehdr *hdr,
/* Any cleanup needed when module leaves. */
void module_arch_cleanup(struct module *mod);
/* Any cleanup before freeing mod->module_init */
void module_arch_freeing_init(struct module *mod);
#endif

View File

@ -1804,6 +1804,10 @@ void __weak module_arch_cleanup(struct module *mod)
{
}
void __weak module_arch_freeing_init(struct module *mod)
{
}
/* Free a module, remove from lists, etc. */
static void free_module(struct module *mod)
{
@ -1841,6 +1845,7 @@ static void free_module(struct module *mod)
/* This may be NULL, but that's OK */
unset_module_init_ro_nx(mod);
module_arch_freeing_init(mod);
module_free(mod, mod->module_init);
kfree(mod->args);
percpu_modfree(mod);
@ -2930,6 +2935,7 @@ static struct module *layout_and_allocate(struct load_info *info, int flags)
static void module_deallocate(struct module *mod, struct load_info *info)
{
percpu_modfree(mod);
module_arch_freeing_init(mod);
module_free(mod, mod->module_init);
module_free(mod, mod->module_core);
}
@ -3055,6 +3061,7 @@ static int do_init_module(struct module *mod)
mod->strtab = mod->core_strtab;
#endif
unset_module_init_ro_nx(mod);
module_arch_freeing_init(mod);
module_free(mod, mod->module_init);
mod->module_init = NULL;
mod->init_size = 0;