[PATCHv6 iproute2-next 2/5] lib: make ipvrf able to use libbpf and fix function name conflicts

[Hangbin Liu <haliu@redhat.com>]

There are directly calls in libbpf for bpf program load/attach.
So we could just use two wrapper functions for ipvrf and convert
them with libbpf support.

Function bpf_prog_load() is removed as it's conflict with libbpf
function name.

bpf.c is moved to bpf_legacy.c for later main libbpf support in
iproute2.

Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Hangbin Liu <haliu@redhat.com>
---
v6: bpf_glue.c is created in previous patch. So I changed the commit
    description.
v5: Fix bpf_prog_load_dev typo.
v4: Add new file bpf_glue.c
v2-v3: no update
---
 include/bpf_util.h          | 10 +++++++---
 ip/ipvrf.c                  |  6 +++---
 lib/Makefile                |  2 +-
 lib/bpf_glue.c              | 23 +++++++++++++++++++++++
 lib/{bpf.c => bpf_legacy.c} | 15 +++------------
 5 files changed, 37 insertions(+), 19 deletions(-)
 rename lib/{bpf.c => bpf_legacy.c} (99%)

diff --git a/include/bpf_util.h b/include/bpf_util.h
index dee5bb02..3235c34e 100644
--- a/include/bpf_util.h
+++ b/include/bpf_util.h
@@ -274,12 +274,16 @@ int bpf_trace_pipe(void);
 
 void bpf_print_ops(struct rtattr *bpf_ops, __u16 len);
 
-int bpf_prog_load(enum bpf_prog_type type, const struct bpf_insn *insns,
-		  size_t size_insns, const char *license, char *log,
-		  size_t size_log);
+int bpf_prog_load_dev(enum bpf_prog_type type, const struct bpf_insn *insns,
+		      size_t size_insns, const char *license, __u32 ifindex,
+		      char *log, size_t size_log);
+int bpf_program_load(enum bpf_prog_type type, const struct bpf_insn *insns,
+		     size_t size_insns, const char *license, char *log,
+		     size_t size_log);
 
 int bpf_prog_attach_fd(int prog_fd, int target_fd, enum bpf_attach_type type);
 int bpf_prog_detach_fd(int target_fd, enum bpf_attach_type type);
+int bpf_program_attach(int prog_fd, int target_fd, enum bpf_attach_type type);
 
 int bpf_dump_prog_info(FILE *f, uint32_t id);
 
diff --git a/ip/ipvrf.c b/ip/ipvrf.c
index 28dd8e25..42779e5c 100644
--- a/ip/ipvrf.c
+++ b/ip/ipvrf.c
@@ -256,8 +256,8 @@ static int prog_load(int idx)
 		BPF_EXIT_INSN(),
 	};
 
-	return bpf_prog_load(BPF_PROG_TYPE_CGROUP_SOCK, prog, sizeof(prog),
-			     "GPL", bpf_log_buf, sizeof(bpf_log_buf));
+	return bpf_program_load(BPF_PROG_TYPE_CGROUP_SOCK, prog, sizeof(prog),
+			        "GPL", bpf_log_buf, sizeof(bpf_log_buf));
 }
 
 static int vrf_configure_cgroup(const char *path, int ifindex)
@@ -288,7 +288,7 @@ static int vrf_configure_cgroup(const char *path, int ifindex)
 		goto out;
 	}
 
-	if (bpf_prog_attach_fd(prog_fd, cg_fd, BPF_CGROUP_INET_SOCK_CREATE)) {
+	if (bpf_program_attach(prog_fd, cg_fd, BPF_CGROUP_INET_SOCK_CREATE)) {
 		fprintf(stderr, "Failed to attach prog to cgroup: '%s'\n",
 			strerror(errno));
 		goto out;
diff --git a/lib/Makefile b/lib/Makefile
index a02775a5..7c8a197c 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -5,7 +5,7 @@ CFLAGS += -fPIC
 
 UTILOBJ = utils.o rt_names.o ll_map.o ll_types.o ll_proto.o ll_addr.o \
 	inet_proto.o namespace.o json_writer.o json_print.o \
-	names.o color.o bpf.o bpf_glue.o exec.o fs.o cg_map.o
+	names.o color.o bpf_legacy.o bpf_glue.o exec.o fs.o cg_map.o
 
 NLOBJ=libgenl.o libnetlink.o mnl_utils.o
 
diff --git a/lib/bpf_glue.c b/lib/bpf_glue.c
index 67c41c22..fa609bfe 100644
--- a/lib/bpf_glue.c
+++ b/lib/bpf_glue.c
@@ -5,6 +5,29 @@
  *
  */
 #include "bpf_util.h"
+#ifdef HAVE_LIBBPF
+#include <bpf/bpf.h>
+#endif
+
+int bpf_program_load(enum bpf_prog_type type, const struct bpf_insn *insns,
+		     size_t size_insns, const char *license, char *log,
+		     size_t size_log)
+{
+#ifdef HAVE_LIBBPF
+	return bpf_load_program(type, insns, size_insns, license, 0, log, size_log);
+#else
+	return bpf_prog_load_dev(type, insns, size_insns, license, 0, log, size_log);
+#endif
+}
+
+int bpf_program_attach(int prog_fd, int target_fd, enum bpf_attach_type type)
+{
+#ifdef HAVE_LIBBPF
+	return bpf_prog_attach(prog_fd, target_fd, type, 0);
+#else
+	return bpf_prog_attach_fd(prog_fd, target_fd, type);
+#endif
+}
 
 #ifdef HAVE_LIBBPF
 static const char *_libbpf_compile_version = LIBBPF_VERSION;
diff --git a/lib/bpf.c b/lib/bpf_legacy.c
similarity index 99%
rename from lib/bpf.c
rename to lib/bpf_legacy.c
index c7d45077..4246fb76 100644
--- a/lib/bpf.c
+++ b/lib/bpf_legacy.c
@@ -1087,10 +1087,9 @@ int bpf_prog_detach_fd(int target_fd, enum bpf_attach_type type)
 	return bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
 }
 
-static int bpf_prog_load_dev(enum bpf_prog_type type,
-			     const struct bpf_insn *insns, size_t size_insns,
-			     const char *license, __u32 ifindex,
-			     char *log, size_t size_log)
+int bpf_prog_load_dev(enum bpf_prog_type type, const struct bpf_insn *insns,
+		      size_t size_insns, const char *license, __u32 ifindex,
+		      char *log, size_t size_log)
 {
 	union bpf_attr attr = {};
 
@@ -1109,14 +1108,6 @@ static int bpf_prog_load_dev(enum bpf_prog_type type,
 	return bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
 }
 
-int bpf_prog_load(enum bpf_prog_type type, const struct bpf_insn *insns,
-		  size_t size_insns, const char *license, char *log,
-		  size_t size_log)
-{
-	return bpf_prog_load_dev(type, insns, size_insns, license, 0,
-				 log, size_log);
-}
-
 #ifdef HAVE_ELF
 struct bpf_elf_prog {
 	enum bpf_prog_type	type;
-- 
2.25.4