Extend libbpf attach opts and add a new detach opts API so this can be used
to add/remove fd-based tcx BPF programs. The old-style bpf_prog_detach and
bpf_prog_detach2 APIs are refactored to reuse the detach opts internally.
The bpf_prog_query_opts API got extended to be able to handle the new link_ids,
link_attach_flags and revision fields.
For concrete usage examples, see the extensive selftests that have been
developed as part of this series.
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
---
tools/lib/bpf/bpf.c | 78 ++++++++++++++++++++++------------------
tools/lib/bpf/bpf.h | 54 +++++++++++++++++++++-------
tools/lib/bpf/libbpf.c | 6 ++++
tools/lib/bpf/libbpf.map | 1 +
4 files changed, 91 insertions(+), 48 deletions(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index ed86b37d8024..a3d1b7ebe224 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -629,11 +629,21 @@ int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
return bpf_prog_attach_opts(prog_fd, target_fd, type, &opts);
}
-int bpf_prog_attach_opts(int prog_fd, int target_fd,
- enum bpf_attach_type type,
- const struct bpf_prog_attach_opts *opts)
+int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
+{
+ return bpf_prog_detach_opts(0, target_fd, type, NULL);
+}
+
+int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
{
- const size_t attr_sz = offsetofend(union bpf_attr, replace_bpf_fd);
+ return bpf_prog_detach_opts(prog_fd, target_fd, type, NULL);
+}
+
+int bpf_prog_attach_opts(int prog_fd, int target,
+ enum bpf_attach_type type,
+ const struct bpf_prog_attach_opts *opts)
+{
+ const size_t attr_sz = offsetofend(union bpf_attr, expected_revision);
union bpf_attr attr;
int ret;
@@ -641,40 +651,35 @@ int bpf_prog_attach_opts(int prog_fd, int target_fd,
return libbpf_err(-EINVAL);
memset(&attr, 0, attr_sz);
- attr.target_fd = target_fd;
- attr.attach_bpf_fd = prog_fd;
- attr.attach_type = type;
- attr.attach_flags = OPTS_GET(opts, flags, 0);
- attr.replace_bpf_fd = OPTS_GET(opts, replace_prog_fd, 0);
+ attr.target_fd = target;
+ attr.attach_bpf_fd = prog_fd;
+ attr.attach_type = type;
+ attr.attach_flags = OPTS_GET(opts, flags, 0);
+ attr.replace_bpf_fd = OPTS_GET(opts, relative_fd, 0);
+ attr.expected_revision = OPTS_GET(opts, expected_revision, 0);
ret = sys_bpf(BPF_PROG_ATTACH, &attr, attr_sz);
return libbpf_err_errno(ret);
}
-int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
+int bpf_prog_detach_opts(int prog_fd, int target,
+ enum bpf_attach_type type,
+ const struct bpf_prog_detach_opts *opts)
{
- const size_t attr_sz = offsetofend(union bpf_attr, replace_bpf_fd);
+ const size_t attr_sz = offsetofend(union bpf_attr, expected_revision);
union bpf_attr attr;
int ret;
- memset(&attr, 0, attr_sz);
- attr.target_fd = target_fd;
- attr.attach_type = type;
-
- ret = sys_bpf(BPF_PROG_DETACH, &attr, attr_sz);
- return libbpf_err_errno(ret);
-}
-
-int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
-{
- const size_t attr_sz = offsetofend(union bpf_attr, replace_bpf_fd);
- union bpf_attr attr;
- int ret;
+ if (!OPTS_VALID(opts, bpf_prog_detach_opts))
+ return libbpf_err(-EINVAL);
memset(&attr, 0, attr_sz);
- attr.target_fd = target_fd;
- attr.attach_bpf_fd = prog_fd;
- attr.attach_type = type;
+ attr.target_fd = target;
+ attr.attach_bpf_fd = prog_fd;
+ attr.attach_type = type;
+ attr.attach_flags = OPTS_GET(opts, flags, 0);
+ attr.replace_bpf_fd = OPTS_GET(opts, relative_fd, 0);
+ attr.expected_revision = OPTS_GET(opts, expected_revision, 0);
ret = sys_bpf(BPF_PROG_DETACH, &attr, attr_sz);
return libbpf_err_errno(ret);
@@ -833,7 +838,7 @@ int bpf_iter_create(int link_fd)
return libbpf_err_errno(fd);
}
-int bpf_prog_query_opts(int target_fd,
+int bpf_prog_query_opts(int target,
enum bpf_attach_type type,
struct bpf_prog_query_opts *opts)
{
@@ -846,17 +851,20 @@ int bpf_prog_query_opts(int target_fd,
memset(&attr, 0, attr_sz);
- attr.query.target_fd = target_fd;
- attr.query.attach_type = type;
- attr.query.query_flags = OPTS_GET(opts, query_flags, 0);
- attr.query.prog_cnt = OPTS_GET(opts, prog_cnt, 0);
- attr.query.prog_ids = ptr_to_u64(OPTS_GET(opts, prog_ids, NULL));
- attr.query.prog_attach_flags = ptr_to_u64(OPTS_GET(opts, prog_attach_flags, NULL));
+ attr.query.target_fd = target;
+ attr.query.attach_type = type;
+ attr.query.query_flags = OPTS_GET(opts, query_flags, 0);
+ attr.query.count = OPTS_GET(opts, count, 0);
+ attr.query.prog_ids = ptr_to_u64(OPTS_GET(opts, prog_ids, NULL));
+ attr.query.prog_attach_flags = ptr_to_u64(OPTS_GET(opts, prog_attach_flags, NULL));
+ attr.query.link_ids = ptr_to_u64(OPTS_GET(opts, link_ids, NULL));
+ attr.query.link_attach_flags = ptr_to_u64(OPTS_GET(opts, link_attach_flags, NULL));
ret = sys_bpf(BPF_PROG_QUERY, &attr, attr_sz);
OPTS_SET(opts, attach_flags, attr.query.attach_flags);
- OPTS_SET(opts, prog_cnt, attr.query.prog_cnt);
+ OPTS_SET(opts, revision, attr.query.revision);
+ OPTS_SET(opts, count, attr.query.count);
return libbpf_err_errno(ret);
}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 9aa0ee473754..480c584a6f7f 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -312,22 +312,43 @@ LIBBPF_API int bpf_obj_get(const char *pathname);
LIBBPF_API int bpf_obj_get_opts(const char *pathname,
const struct bpf_obj_get_opts *opts);
-struct bpf_prog_attach_opts {
- size_t sz; /* size of this struct for forward/backward compatibility */
- unsigned int flags;
- int replace_prog_fd;
-};
-#define bpf_prog_attach_opts__last_field replace_prog_fd
-
LIBBPF_API int bpf_prog_attach(int prog_fd, int attachable_fd,
enum bpf_attach_type type, unsigned int flags);
-LIBBPF_API int bpf_prog_attach_opts(int prog_fd, int attachable_fd,
- enum bpf_attach_type type,
- const struct bpf_prog_attach_opts *opts);
LIBBPF_API int bpf_prog_detach(int attachable_fd, enum bpf_attach_type type);
LIBBPF_API int bpf_prog_detach2(int prog_fd, int attachable_fd,
enum bpf_attach_type type);
+struct bpf_prog_attach_opts {
+ size_t sz; /* size of this struct for forward/backward compatibility */
+ __u32 flags;
+ union {
+ int replace_prog_fd;
+ int replace_fd;
+ int relative_fd;
+ __u32 relative_id;
+ };
+ __u32 expected_revision;
+};
+#define bpf_prog_attach_opts__last_field expected_revision
+
+struct bpf_prog_detach_opts {
+ size_t sz; /* size of this struct for forward/backward compatibility */
+ __u32 flags;
+ union {
+ int relative_fd;
+ __u32 relative_id;
+ };
+ __u32 expected_revision;
+};
+#define bpf_prog_detach_opts__last_field expected_revision
+
+LIBBPF_API int bpf_prog_attach_opts(int prog_fd, int target,
+ enum bpf_attach_type type,
+ const struct bpf_prog_attach_opts *opts);
+LIBBPF_API int bpf_prog_detach_opts(int prog_fd, int target,
+ enum bpf_attach_type type,
+ const struct bpf_prog_detach_opts *opts);
+
union bpf_iter_link_info; /* defined in up-to-date linux/bpf.h */
struct bpf_link_create_opts {
size_t sz; /* size of this struct for forward/backward compatibility */
@@ -489,14 +510,21 @@ struct bpf_prog_query_opts {
__u32 query_flags;
__u32 attach_flags; /* output argument */
__u32 *prog_ids;
- __u32 prog_cnt; /* input+output argument */
+ union {
+ __u32 prog_cnt; /* input+output argument */
+ __u32 count;
+ };
__u32 *prog_attach_flags;
+ __u32 *link_ids;
+ __u32 *link_attach_flags;
+ __u32 revision;
};
-#define bpf_prog_query_opts__last_field prog_attach_flags
+#define bpf_prog_query_opts__last_field revision
-LIBBPF_API int bpf_prog_query_opts(int target_fd,
+LIBBPF_API int bpf_prog_query_opts(int target,
enum bpf_attach_type type,
struct bpf_prog_query_opts *opts);
+
LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type,
__u32 query_flags, __u32 *attach_flags,
__u32 *prog_ids, __u32 *prog_cnt);
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 47632606b06d..b89127471c6a 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -117,6 +117,8 @@ static const char * const attach_type_name[] = {
[BPF_PERF_EVENT] = "perf_event",
[BPF_TRACE_KPROBE_MULTI] = "trace_kprobe_multi",
[BPF_STRUCT_OPS] = "struct_ops",
+ [BPF_TCX_INGRESS] = "tcx_ingress",
+ [BPF_TCX_EGRESS] = "tcx_egress",
};
static const char * const link_type_name[] = {
@@ -8669,6 +8671,10 @@ static const struct bpf_sec_def section_defs[] = {
SEC_DEF("kretsyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall),
SEC_DEF("usdt+", KPROBE, 0, SEC_NONE, attach_usdt),
SEC_DEF("tc", SCHED_CLS, 0, SEC_NONE),
+ SEC_DEF("tc/ingress", SCHED_CLS, BPF_TCX_INGRESS, SEC_ATTACHABLE_OPT),
+ SEC_DEF("tc/egress", SCHED_CLS, BPF_TCX_EGRESS, SEC_ATTACHABLE_OPT),
+ SEC_DEF("tcx/ingress", SCHED_CLS, BPF_TCX_INGRESS, SEC_ATTACHABLE_OPT),
+ SEC_DEF("tcx/egress", SCHED_CLS, BPF_TCX_EGRESS, SEC_ATTACHABLE_OPT),
SEC_DEF("classifier", SCHED_CLS, 0, SEC_NONE),
SEC_DEF("action", SCHED_ACT, 0, SEC_NONE),
SEC_DEF("tracepoint+", TRACEPOINT, 0, SEC_NONE, attach_tp),
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 7521a2fb7626..a29b90e9713c 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -395,4 +395,5 @@ LIBBPF_1.2.0 {
LIBBPF_1.3.0 {
global:
bpf_obj_pin_opts;
+ bpf_prog_detach_opts;
} LIBBPF_1.2.0;
--
2.34.1
