@@ -3,6 +3,7 @@
#ifndef _LINUX_BPFPTR_H
#define _LINUX_BPFPTR_H
+#include <linux/mm.h>
#include <linux/sockptr.h>
typedef sockptr_t bpfptr_t;
@@ -5,6 +5,7 @@
#define _LINUX_BTF_H 1
#include <linux/types.h>
+#include <linux/bpfptr.h>
#include <uapi/linux/btf.h>
#include <uapi/linux/bpf.h>
@@ -238,4 +239,18 @@ static inline const char *btf_name_by_offset(const struct btf *btf,
}
#endif
+struct kfunc_btf_set {
+ struct list_head list;
+ struct btf_id_set *set;
+};
+
+/* Register set of BTF ids */
+#define DECLARE_KFUNC_BTF_SET_REG(type) \
+ void register_##type##_kfunc_btf_set(struct kfunc_btf_set *s); \
+ bool __bpf_check_##type##_kfunc_call(u32 kfunc_id); \
+ void unregister_##type##_kfunc_btf_set(struct kfunc_btf_set *s)
+
+#define DEFINE_KFUNC_BTF_SET(set, name) \
+ struct kfunc_btf_set name = { LIST_HEAD_INIT(name.list), (set) }
+
#endif
@@ -6215,3 +6215,37 @@ const struct bpf_func_proto bpf_btf_find_by_name_kind_proto = {
};
BTF_ID_LIST_GLOBAL_SINGLE(btf_task_struct_ids, struct, task_struct)
+
+/* Typesafe helpers to register BTF ID sets for modules */
+#define DEFINE_KFUNC_BTF_SET_REG(type) \
+ static DEFINE_MUTEX(type##_kfunc_btf_set_mutex); \
+ static LIST_HEAD(type##_kfunc_btf_set_list); \
+ void register_##type##_kfunc_btf_set(struct kfunc_btf_set *s) \
+ { \
+ mutex_lock(&type##_kfunc_btf_set_mutex); \
+ list_add(&s->list, &type##_kfunc_btf_set_list); \
+ mutex_unlock(&type##_kfunc_btf_set_mutex); \
+ } \
+ EXPORT_SYMBOL_GPL(register_##type##_kfunc_btf_set); \
+ bool __bpf_check_##type##_kfunc_call(u32 kfunc_id) \
+ { \
+ struct kfunc_btf_set *s; \
+ mutex_lock(&type##_kfunc_btf_set_mutex); \
+ list_for_each_entry(s, &type##_kfunc_btf_set_list, list) { \
+ if (btf_id_set_contains(s->set, kfunc_id)) { \
+ mutex_unlock(&type##_kfunc_btf_set_mutex); \
+ return true; \
+ } \
+ } \
+ mutex_unlock(&type##_kfunc_btf_set_mutex); \
+ return false; \
+ } \
+ void unregister_##type##_kfunc_btf_set(struct kfunc_btf_set *s) \
+ { \
+ if (!s) \
+ return; \
+ mutex_lock(&type##_kfunc_btf_set_mutex); \
+ list_del_init(&s->list); \
+ mutex_unlock(&type##_kfunc_btf_set_mutex); \
+ } \
+ EXPORT_SYMBOL_GPL(unregister_##type##_kfunc_btf_set)
This adds macros that generate BTF set registration APIs and check_kfunc_call callback. These require a type, which namespaces each BTF set. This is in preparation to allow for nf_conntrack registering unstable helpers it wants to expose to XDP and SCHED_CLS programs in subsequent patches. With in kernel sets, the way this is supposed to work is, in kernel callback looks up within the in-kernel kfunc whitelist, and then defers to the dynamic BTF set lookup if it doesn't find the BTF id. If there is no in-kernel BTF id set, this callback can be directly used. Also fix includes for btf.h and bpfptr.h so that they can included in isolation. This is in preparation for their usage in tcp_bbr, tcp_cubic and tcp_dctcp modules in the next patch. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> --- include/linux/bpfptr.h | 1 + include/linux/btf.h | 15 +++++++++++++++ kernel/bpf/btf.c | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 50 insertions(+)