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-rw-r--r--samples/bpf/bpf_helpers.h40
1 files changed, 40 insertions, 0 deletions
diff --git a/samples/bpf/bpf_helpers.h b/samples/bpf/bpf_helpers.h
new file mode 100644
index 000000000000..ca0333146006
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+++ b/samples/bpf/bpf_helpers.h
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+#ifndef __BPF_HELPERS_H
+#define __BPF_HELPERS_H
+
+/* helper macro to place programs, maps, license in
+ * different sections in elf_bpf file. Section names
+ * are interpreted by elf_bpf loader
+ */
+#define SEC(NAME) __attribute__((section(NAME), used))
+
+/* helper functions called from eBPF programs written in C */
+static void *(*bpf_map_lookup_elem)(void *map, void *key) =
+ (void *) BPF_FUNC_map_lookup_elem;
+static int (*bpf_map_update_elem)(void *map, void *key, void *value,
+ unsigned long long flags) =
+ (void *) BPF_FUNC_map_update_elem;
+static int (*bpf_map_delete_elem)(void *map, void *key) =
+ (void *) BPF_FUNC_map_delete_elem;
+
+/* llvm builtin functions that eBPF C program may use to
+ * emit BPF_LD_ABS and BPF_LD_IND instructions
+ */
+struct sk_buff;
+unsigned long long load_byte(void *skb,
+ unsigned long long off) asm("llvm.bpf.load.byte");
+unsigned long long load_half(void *skb,
+ unsigned long long off) asm("llvm.bpf.load.half");
+unsigned long long load_word(void *skb,
+ unsigned long long off) asm("llvm.bpf.load.word");
+
+/* a helper structure used by eBPF C program
+ * to describe map attributes to elf_bpf loader
+ */
+struct bpf_map_def {
+ unsigned int type;
+ unsigned int key_size;
+ unsigned int value_size;
+ unsigned int max_entries;
+};
+
+#endif