summaryrefslogtreecommitdiff
path: root/tools/lib/bpf
diff options
context:
space:
mode:
authorRoberto Sassu <roberto.sassu@huawei.com>2022-10-06 14:07:32 +0300
committerAndrii Nakryiko <andrii@kernel.org>2022-10-11 02:49:20 +0300
commit243e300563b1b39ac669c7698742931427699184 (patch)
tree843e82b6acbb34e8dd74c885d6d9b2e674437ac6 /tools/lib/bpf
parent7a366da2d2ba86316d3ec408f70d19b63916f9ce (diff)
downloadlinux-243e300563b1b39ac669c7698742931427699184.tar.xz
libbpf: Introduce bpf_get_fd_by_id_opts and bpf_map_get_fd_by_id_opts()
Define a new data structure called bpf_get_fd_by_id_opts, with the member open_flags, to be used by callers of the _opts variants of bpf_*_get_fd_by_id() to specify the permissions needed for the file descriptor to be obtained. Also, introduce bpf_map_get_fd_by_id_opts(), to let the caller pass a bpf_get_fd_by_id_opts structure. Finally, keep the existing bpf_map_get_fd_by_id(), and call bpf_map_get_fd_by_id_opts() with NULL as opts argument, to request read-write permissions (current behavior). Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20221006110736.84253-3-roberto.sassu@huaweicloud.com
Diffstat (limited to 'tools/lib/bpf')
-rw-r--r--tools/lib/bpf/bpf.c12
-rw-r--r--tools/lib/bpf/bpf.h10
-rw-r--r--tools/lib/bpf/libbpf.map1
3 files changed, 22 insertions, 1 deletions
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 1d49a0352836..c08d7509553d 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -948,19 +948,29 @@ int bpf_prog_get_fd_by_id(__u32 id)
return libbpf_err_errno(fd);
}
-int bpf_map_get_fd_by_id(__u32 id)
+int bpf_map_get_fd_by_id_opts(__u32 id,
+ const struct bpf_get_fd_by_id_opts *opts)
{
const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
union bpf_attr attr;
int fd;
+ if (!OPTS_VALID(opts, bpf_get_fd_by_id_opts))
+ return libbpf_err(-EINVAL);
+
memset(&attr, 0, attr_sz);
attr.map_id = id;
+ attr.open_flags = OPTS_GET(opts, open_flags, 0);
fd = sys_bpf_fd(BPF_MAP_GET_FD_BY_ID, &attr, attr_sz);
return libbpf_err_errno(fd);
}
+int bpf_map_get_fd_by_id(__u32 id)
+{
+ return bpf_map_get_fd_by_id_opts(id, NULL);
+}
+
int bpf_btf_get_fd_by_id(__u32 id)
{
const size_t attr_sz = offsetofend(union bpf_attr, open_flags);
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 9c50beabdd14..10ce38f0a9ef 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -365,8 +365,18 @@ LIBBPF_API int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_map_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_link_get_next_id(__u32 start_id, __u32 *next_id);
+
+struct bpf_get_fd_by_id_opts {
+ size_t sz; /* size of this struct for forward/backward compatibility */
+ __u32 open_flags; /* permissions requested for the operation on fd */
+ size_t :0;
+};
+#define bpf_get_fd_by_id_opts__last_field open_flags
+
LIBBPF_API int bpf_prog_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_map_get_fd_by_id(__u32 id);
+LIBBPF_API int bpf_map_get_fd_by_id_opts(__u32 id,
+ const struct bpf_get_fd_by_id_opts *opts);
LIBBPF_API int bpf_btf_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_link_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 04fab9f1fdd7..2e665b21d84f 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -371,6 +371,7 @@ LIBBPF_1.0.0 {
LIBBPF_1.1.0 {
global:
+ bpf_map_get_fd_by_id_opts;
user_ring_buffer__discard;
user_ring_buffer__free;
user_ring_buffer__new;