Add the flags parameter to map_parse_fds(), and the static function map_fd_by_name() called by it. In the latter function, request the read permission for the map search, and obtain a new file descriptor if the flags variable has a different value.
Also pass the flags to the new functions bpf_map_get_fd_by_id_flags() and the modified function open_obj_pinned_any().
At this point, there is still no change in the current behavior, as the flags argument passed is always zero or the requested permission is a subset (in map_fd_by_name()).
Signed-off-by: Roberto Sassu roberto.sassu@huawei.com --- tools/bpf/bpftool/common.c | 25 ++++++++++++++++++------- tools/bpf/bpftool/main.h | 2 +- tools/bpf/bpftool/map.c | 4 ++-- 3 files changed, 21 insertions(+), 10 deletions(-)
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index 54246109516f..641810b78581 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -799,7 +799,7 @@ int prog_parse_fd(int *argc, char ***argv, __u32 flags) return fd; }
-static int map_fd_by_name(char *name, int **fds) +static int map_fd_by_name(char *name, int **fds, __u32 flags) { unsigned int id = 0; int fd, nb_fds = 0; @@ -819,7 +819,7 @@ static int map_fd_by_name(char *name, int **fds) return nb_fds; }
- fd = bpf_map_get_fd_by_id(id); + fd = bpf_map_get_fd_by_id_flags(id, BPF_F_RDONLY); if (fd < 0) { p_err("can't get map by id (%u): %s", id, strerror(errno)); @@ -838,6 +838,17 @@ static int map_fd_by_name(char *name, int **fds) continue; }
+ if (flags != BPF_F_RDONLY) { + close(fd); + + fd = bpf_map_get_fd_by_id_flags(id, flags); + if (fd < 0) { + p_err("can't get map by id (%u): %s", + id, strerror(errno)); + goto err_close_fds; + } + } + if (nb_fds > 0) { tmp = realloc(*fds, (nb_fds + 1) * sizeof(int)); if (!tmp) { @@ -857,7 +868,7 @@ static int map_fd_by_name(char *name, int **fds) return -1; }
-int map_parse_fds(int *argc, char ***argv, int **fds) +int map_parse_fds(int *argc, char ***argv, int **fds, __u32 flags) { if (is_prefix(**argv, "id")) { unsigned int id; @@ -872,7 +883,7 @@ int map_parse_fds(int *argc, char ***argv, int **fds) } NEXT_ARGP();
- (*fds)[0] = bpf_map_get_fd_by_id(id); + (*fds)[0] = bpf_map_get_fd_by_id_flags(id, flags); if ((*fds)[0] < 0) { p_err("get map by id (%u): %s", id, strerror(errno)); return -1; @@ -890,7 +901,7 @@ int map_parse_fds(int *argc, char ***argv, int **fds) } NEXT_ARGP();
- return map_fd_by_name(name, fds); + return map_fd_by_name(name, fds, flags); } else if (is_prefix(**argv, "pinned")) { char *path;
@@ -899,7 +910,7 @@ int map_parse_fds(int *argc, char ***argv, int **fds) path = **argv; NEXT_ARGP();
- (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP, 0); + (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP, flags); if ((*fds)[0] < 0) return -1; return 1; @@ -919,7 +930,7 @@ int map_parse_fd(int *argc, char ***argv, __u32 flags) p_err("mem alloc failed"); return -1; } - nb_fds = map_parse_fds(argc, argv, &fds); + nb_fds = map_parse_fds(argc, argv, &fds, flags); if (nb_fds != 1) { if (nb_fds > 1) { p_err("several maps match this handle"); diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index f342b2da4d8d..70b0ad6245b9 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -170,7 +170,7 @@ int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what); int prog_parse_fd(int *argc, char ***argv, __u32 flags); int prog_parse_fds(int *argc, char ***argv, int **fds); int map_parse_fd(int *argc, char ***argv, __u32 flags); -int map_parse_fds(int *argc, char ***argv, int **fds); +int map_parse_fds(int *argc, char ***argv, int **fds, __u32 flags); int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len);
struct bpf_prog_linfo; diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index d1231dce7183..9a747918882e 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -634,7 +634,7 @@ static int do_show_subset(int argc, char **argv) p_err("mem alloc failed"); return -1; } - nb_fds = map_parse_fds(&argc, &argv, &fds); + nb_fds = map_parse_fds(&argc, &argv, &fds, 0); if (nb_fds < 1) goto exit_free;
@@ -910,7 +910,7 @@ static int do_dump(int argc, char **argv) p_err("mem alloc failed"); return -1; } - nb_fds = map_parse_fds(&argc, &argv, &fds); + nb_fds = map_parse_fds(&argc, &argv, &fds, 0); if (nb_fds < 1) goto exit_free;