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feat: Update struct_ops to change test_3 return type to int and add BPF helper support

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github-actions[bot]
2025-11-15 23:54:20 +00:00
parent 540ce67c47
commit 86c2f723f0
3 changed files with 18 additions and 7 deletions
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2
src/features/struct_ops/module/bpf_testmod.h
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@@ -5,7 +5,7 @@
struct bpf_testmod_ops { struct bpf_testmod_ops {
int (*test_1)(void); int (*test_1)(void);
int (*test_2)(int a, int b); int (*test_2)(int a, int b);
void (*test_3)(const char *buf, int len); int (*test_3)(const char *buf, int len);
}; };
#endif /* _BPF_TESTMOD_H */ #endif /* _BPF_TESTMOD_H */

16
src/features/struct_ops/module/hello.c
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@@ -6,12 +6,13 @@
#include <linux/btf_ids.h> #include <linux/btf_ids.h>
#include <linux/proc_fs.h> #include <linux/proc_fs.h>
#include <linux/seq_file.h> #include <linux/seq_file.h>
#include <linux/bpf_verifier.h>
/* Define our custom struct_ops operations */ /* Define our custom struct_ops operations */
struct bpf_testmod_ops { struct bpf_testmod_ops {
int (*test_1)(void); int (*test_1)(void);
int (*test_2)(int a, int b); int (*test_2)(int a, int b);
void (*test_3)(const char *buf, int len); int (*test_3)(const char *buf, int len);
}; };
/* Global instance that BPF programs will implement */ /* Global instance that BPF programs will implement */
@@ -31,8 +32,9 @@ static int bpf_testmod_ops__test_2(int a, int b)
return 0; return 0;
} }
static void bpf_testmod_ops__test_3(const char *buf, int len) static int bpf_testmod_ops__test_3(const char *buf, int len)
{ {
return 0;
} }
/* CFI stubs structure */ /* CFI stubs structure */
@@ -58,8 +60,18 @@ static bool bpf_testmod_ops_is_valid_access(int off, int size,
return true; return true;
} }
/* Allow specific BPF helpers to be used in struct_ops programs */
static const struct bpf_func_proto *
bpf_testmod_ops_get_func_proto(enum bpf_func_id func_id,
const struct bpf_prog *prog)
{
/* Use base func proto which includes trace_printk and other basic helpers */
return bpf_base_func_proto(func_id, prog);
}
static const struct bpf_verifier_ops bpf_testmod_verifier_ops = { static const struct bpf_verifier_ops bpf_testmod_verifier_ops = {
.is_valid_access = bpf_testmod_ops_is_valid_access, .is_valid_access = bpf_testmod_ops_is_valid_access,
.get_func_proto = bpf_testmod_ops_get_func_proto,
}; };
static int bpf_testmod_ops_init_member(const struct btf_type *t, static int bpf_testmod_ops_init_member(const struct btf_type *t,

7
src/features/struct_ops/struct_ops.bpf.c
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@@ -23,12 +23,11 @@ int BPF_PROG(bpf_testmod_test_2, int a, int b)
} }
SEC("struct_ops/test_3") SEC("struct_ops/test_3")
void BPF_PROG(bpf_testmod_test_3, const char *buf, int len) int BPF_PROG(bpf_testmod_test_3, const char *buf, int len)
{ {
bpf_printk("BPF test_3 called with buffer length %d\n", len); bpf_printk("BPF test_3 called with buffer length %d\n", len);
if (len > 0) { /* Note: Accessing buf pointer requires proper context setup in kernel module */
bpf_printk("First char: %c\n", buf[0]); return 0;
}
} }
/* Define the struct_ops map */ /* Define the struct_ops map */