xref: /openbmc/linux/kernel/livepatch/patch.h (revision dea54fba)
1 #ifndef _LIVEPATCH_PATCH_H
2 #define _LIVEPATCH_PATCH_H
3 
4 #include <linux/livepatch.h>
5 #include <linux/list.h>
6 #include <linux/ftrace.h>
7 
8 /**
9  * struct klp_ops - structure for tracking registered ftrace ops structs
10  *
11  * A single ftrace_ops is shared between all enabled replacement functions
12  * (klp_func structs) which have the same old_addr.  This allows the switch
13  * between function versions to happen instantaneously by updating the klp_ops
14  * struct's func_stack list.  The winner is the klp_func at the top of the
15  * func_stack (front of the list).
16  *
17  * @node:	node for the global klp_ops list
18  * @func_stack:	list head for the stack of klp_func's (active func is on top)
19  * @fops:	registered ftrace ops struct
20  */
21 struct klp_ops {
22 	struct list_head node;
23 	struct list_head func_stack;
24 	struct ftrace_ops fops;
25 };
26 
27 struct klp_ops *klp_find_ops(unsigned long old_addr);
28 
29 int klp_patch_object(struct klp_object *obj);
30 void klp_unpatch_object(struct klp_object *obj);
31 void klp_unpatch_objects(struct klp_patch *patch);
32 
33 #endif /* _LIVEPATCH_PATCH_H */
34