From 439e7271dc2b63de379e37971dc2f64d71e24f8a Mon Sep 17 00:00:00 2001 From: Joe Lawrence Date: Thu, 31 Aug 2017 16:37:41 -0400 Subject: livepatch: introduce shadow variable API Add exported API for livepatch modules: klp_shadow_get() klp_shadow_alloc() klp_shadow_get_or_alloc() klp_shadow_free() klp_shadow_free_all() that implement "shadow" variables, which allow callers to associate new shadow fields to existing data structures. This is intended to be used by livepatch modules seeking to emulate additions to data structure definitions. See Documentation/livepatch/shadow-vars.txt for a summary of the new shadow variable API, including a few common use cases. See samples/livepatch/livepatch-shadow-* for example modules that demonstrate shadow variables. [jkosina@suse.cz: fix __klp_shadow_get_or_alloc() comment as spotted by Josh] Signed-off-by: Joe Lawrence Acked-by: Josh Poimboeuf Acked-by: Miroslav Benes Signed-off-by: Jiri Kosina --- include/linux/livepatch.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux/livepatch.h') diff --git a/include/linux/livepatch.h b/include/linux/livepatch.h index 194991ef9347..d08eddc00497 100644 --- a/include/linux/livepatch.h +++ b/include/linux/livepatch.h @@ -164,6 +164,14 @@ static inline bool klp_have_reliable_stack(void) IS_ENABLED(CONFIG_HAVE_RELIABLE_STACKTRACE); } +void *klp_shadow_get(void *obj, unsigned long id); +void *klp_shadow_alloc(void *obj, unsigned long id, void *data, + size_t size, gfp_t gfp_flags); +void *klp_shadow_get_or_alloc(void *obj, unsigned long id, void *data, + size_t size, gfp_t gfp_flags); +void klp_shadow_free(void *obj, unsigned long id); +void klp_shadow_free_all(unsigned long id); + #else /* !CONFIG_LIVEPATCH */ static inline int klp_module_coming(struct module *mod) { return 0; } -- cgit v1.2.3-59-g8ed1b