Before this patch libbpf can only load program with type
BPF_PROG_TYPE_KPROBE program. To make libbpf useful in other scenarios,
this patch introduced bpf_program__set_type() and
bpf_object__set_type() which allows setting program type.
This changes doesn't break old API. The default program type is
BPF_PROG_TYPE_KPROBE. If caller wants to load program with other type,
one of these API should be called before bpf_object__load() or
in callback function of loader.
Signed-off-by: Wang Nan <wangn...@huawei.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
---
tools/lib/bpf/libbpf.c | 43 ++++++++++++++++++++++++++++++++++++++-----
tools/lib/bpf/libbpf.h | 16 ++++++++++++++++
2 files changed, 54 insertions(+), 5 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 8334a5a..99be7f1 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -66,6 +66,7 @@ void libbpf_set_print(libbpf_print_fn_t warn,
#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START)
#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c)
#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
+#define BPF_PROG_TYPE_MAX BPF_PROG_TYPE_SCHED_ACT
static const char *libbpf_strerror_table[NR_ERRNO] = {
[ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf",
@@ -161,6 +162,7 @@ struct bpf_program {
struct bpf_object *obj;
void *priv;
bpf_program_clear_priv_t clear_priv;
+ enum bpf_prog_type type;
};
struct bpf_map {
@@ -323,6 +325,7 @@ bpf_object__add_program(struct bpf_object *obj, void *data,
size_t size,
obj->programs = progs;
obj->nr_programs = nr_progs + 1;
prog.obj = obj;
+ prog.type = BPF_PROG_TYPE_KPROBE;
progs[nr_progs] = prog;
return 0;
}
@@ -871,7 +874,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
}
static int
-load_program(struct bpf_insn *insns, int insns_cnt,
+load_program(struct bpf_insn *insns, int insns_cnt, enum bpf_prog_type type,
char *license, u32 kern_version, int *pfd)
{
int ret;
@@ -884,9 +887,8 @@ load_program(struct bpf_insn *insns, int insns_cnt,
if (!log_buf)
pr_warning("Alloc log buffer for bpf loader error, continue
without log\n");
- ret = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
- insns_cnt, license, kern_version,
- log_buf, BPF_LOG_BUF_SIZE);
+ ret = bpf_load_program(type, insns, insns_cnt, license,
+ kern_version, log_buf, BPF_LOG_BUF_SIZE);
if (ret >= 0) {
*pfd = ret;
@@ -945,7 +947,7 @@ bpf_program__load(struct bpf_program *prog,
pr_warning("Program '%s' is inconsistent: nr(%d) !=
1\n",
prog->section_name, prog->instances.nr);
}
- err = load_program(prog->insns, prog->insns_cnt,
+ err = load_program(prog->insns, prog->insns_cnt, prog->type,
license, kern_version, &fd);
if (!err)
prog->instances.fds[0] = fd;
@@ -976,6 +978,7 @@ bpf_program__load(struct bpf_program *prog,
err = load_program(result.new_insn_ptr,
result.new_insn_cnt,
+ prog->type,
license, kern_version, &fd);
if (err) {
@@ -1192,6 +1195,25 @@ bpf_object__get_kversion(struct bpf_object *obj)
return obj->kern_version;
}
+int bpf_object__set_type(struct bpf_object *obj,
+ enum bpf_prog_type type)
+{
+ struct bpf_program *prog;
+ int err;
+
+ if (!obj || type <= BPF_PROG_TYPE_UNSPEC ||
+ type > BPF_PROG_TYPE_MAX)
+ return -EINVAL;
+
+ bpf_object__for_each_program(prog, obj) {
+ err = bpf_program__set_type(prog, type);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
struct bpf_program *
bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
{
@@ -1281,6 +1303,17 @@ int bpf_program__set_prep(struct bpf_program *prog, int
nr_instances,
return 0;
}
+int bpf_program__set_type(struct bpf_program *prog,
+ enum bpf_prog_type type)
+{
+ if (!prog || type <= BPF_PROG_TYPE_UNSPEC ||
+ type > BPF_PROG_TYPE_MAX)
+ return -EINVAL;
+
+ prog->type = type;
+ return 0;
+}
+
int bpf_program__nth_fd(struct bpf_program *prog, int n)
{
int fd;
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index a51594c..c9d4130 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -11,6 +11,7 @@
#include <stdio.h>
#include <stdbool.h>
#include <linux/err.h>
+#include <linux/bpf.h>
enum libbpf_errno {
__LIBBPF_ERRNO__START = 4000,
@@ -58,6 +59,13 @@ int bpf_object__unload(struct bpf_object *obj);
const char *bpf_object__get_name(struct bpf_object *obj);
unsigned int bpf_object__get_kversion(struct bpf_object *obj);
+/*
+ * Set type of all programs in an object.
+ * See bpf_program__set_type().
+ */
+int bpf_object__set_type(struct bpf_object *obj,
+ enum bpf_prog_type type);
+
struct bpf_object *bpf_object__next(struct bpf_object *prev);
#define bpf_object__for_each_safe(pos, tmp) \
for ((pos) = bpf_object__next(NULL), \
@@ -150,6 +158,14 @@ typedef int (*bpf_program_prep_t)(struct bpf_program
*prog, int n,
int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
bpf_program_prep_t prep);
+/*
+ * Set type of a program. Default is BPF_PROG_TYPE_KPROBE.
+ * This function should be called before bpf_object__load()
+ * or in bpf_program_prep callback.
+ */
+int bpf_program__set_type(struct bpf_program *prog,
+ enum bpf_prog_type type);
+
int bpf_program__nth_fd(struct bpf_program *prog, int n);
/*
--
1.8.3.4
--
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