diff options
Diffstat (limited to 'tools/lib/bpf/libbpf.h')
-rw-r--r-- | tools/lib/bpf/libbpf.h | 193 |
1 files changed, 149 insertions, 44 deletions
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index f177d897c5f7..9de0f299706b 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -83,12 +83,15 @@ struct bpf_object_open_opts { * Non-relocatable instructions are replaced with invalid ones to * prevent accidental errors. * */ + LIBBPF_DEPRECATED_SINCE(0, 6, "field has no effect") bool relaxed_core_relocs; /* maps that set the 'pinning' attribute in their definition will have * their pin_path attribute set to a file in this directory, and be * auto-pinned to that path on load; defaults to "/sys/fs/bpf". */ const char *pin_root_path; + + LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__set_attach_target() on each individual bpf_program") __u32 attach_prog_fd; /* Additional kernel config content that augments and overrides * system Kconfig for CONFIG_xxx externs. @@ -147,6 +150,7 @@ struct bpf_object_load_attr { /* Load/unload object into/from kernel */ LIBBPF_API int bpf_object__load(struct bpf_object *obj); LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr); +LIBBPF_DEPRECATED_SINCE(0, 6, "bpf_object__unload() is deprecated, use bpf_object__close() instead") LIBBPF_API int bpf_object__unload(struct bpf_object *obj); LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj); @@ -164,7 +168,8 @@ LIBBPF_API struct bpf_program * bpf_object__find_program_by_name(const struct bpf_object *obj, const char *name); -LIBBPF_API struct bpf_object *bpf_object__next(struct bpf_object *prev); +LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "track bpf_objects in application code instead") +struct bpf_object *bpf_object__next(struct bpf_object *prev); #define bpf_object__for_each_safe(pos, tmp) \ for ((pos) = bpf_object__next(NULL), \ (tmp) = bpf_object__next(pos); \ @@ -186,16 +191,22 @@ LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name, /* Accessors of bpf_program */ struct bpf_program; -LIBBPF_API struct bpf_program *bpf_program__next(struct bpf_program *prog, - const struct bpf_object *obj); +LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_program() instead") +struct bpf_program *bpf_program__next(struct bpf_program *prog, + const struct bpf_object *obj); +LIBBPF_API struct bpf_program * +bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog); -#define bpf_object__for_each_program(pos, obj) \ - for ((pos) = bpf_program__next(NULL, (obj)); \ - (pos) != NULL; \ - (pos) = bpf_program__next((pos), (obj))) +#define bpf_object__for_each_program(pos, obj) \ + for ((pos) = bpf_object__next_program((obj), NULL); \ + (pos) != NULL; \ + (pos) = bpf_object__next_program((obj), (pos))) -LIBBPF_API struct bpf_program *bpf_program__prev(struct bpf_program *prog, - const struct bpf_object *obj); +LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_program() instead") +struct bpf_program *bpf_program__prev(struct bpf_program *prog, + const struct bpf_object *obj); +LIBBPF_API struct bpf_program * +bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog); typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *); @@ -214,14 +225,51 @@ LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog); LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload); /* returns program size in bytes */ +LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insn_cnt() instead") LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog); +struct bpf_insn; + +/** + * @brief **bpf_program__insns()** gives read-only access to BPF program's + * underlying BPF instructions. + * @param prog BPF program for which to return instructions + * @return a pointer to an array of BPF instructions that belong to the + * specified BPF program + * + * Returned pointer is always valid and not NULL. Number of `struct bpf_insn` + * pointed to can be fetched using **bpf_program__insn_cnt()** API. + * + * Keep in mind, libbpf can modify and append/delete BPF program's + * instructions as it processes BPF object file and prepares everything for + * uploading into the kernel. So depending on the point in BPF object + * lifetime, **bpf_program__insns()** can return different sets of + * instructions. As an example, during BPF object load phase BPF program + * instructions will be CO-RE-relocated, BPF subprograms instructions will be + * appended, ldimm64 instructions will have FDs embedded, etc. So instructions + * returned before **bpf_object__load()** and after it might be quite + * different. + */ +LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog); +/** + * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s + * that form specified BPF program. + * @param prog BPF program for which to return number of BPF instructions + * + * See **bpf_program__insns()** documentation for notes on how libbpf can + * change instructions and their count during different phases of + * **bpf_object** lifetime. + */ +LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog); + LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_version); LIBBPF_API int bpf_program__fd(const struct bpf_program *prog); +LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated") LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog, const char *path, int instance); +LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated") LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog, const char *path, int instance); @@ -243,7 +291,7 @@ LIBBPF_API int bpf_link__detach(struct bpf_link *link); LIBBPF_API int bpf_link__destroy(struct bpf_link *link); LIBBPF_API struct bpf_link * -bpf_program__attach(struct bpf_program *prog); +bpf_program__attach(const struct bpf_program *prog); struct bpf_perf_event_opts { /* size of this struct, for forward/backward compatiblity */ @@ -254,10 +302,10 @@ struct bpf_perf_event_opts { #define bpf_perf_event_opts__last_field bpf_cookie LIBBPF_API struct bpf_link * -bpf_program__attach_perf_event(struct bpf_program *prog, int pfd); +bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd); LIBBPF_API struct bpf_link * -bpf_program__attach_perf_event_opts(struct bpf_program *prog, int pfd, +bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd, const struct bpf_perf_event_opts *opts); struct bpf_kprobe_opts { @@ -266,7 +314,7 @@ struct bpf_kprobe_opts { /* custom user-provided value fetchable through bpf_get_attach_cookie() */ __u64 bpf_cookie; /* function's offset to install kprobe to */ - unsigned long offset; + size_t offset; /* kprobe is return probe */ bool retprobe; size_t :0; @@ -274,10 +322,10 @@ struct bpf_kprobe_opts { #define bpf_kprobe_opts__last_field retprobe LIBBPF_API struct bpf_link * -bpf_program__attach_kprobe(struct bpf_program *prog, bool retprobe, +bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe, const char *func_name); LIBBPF_API struct bpf_link * -bpf_program__attach_kprobe_opts(struct bpf_program *prog, +bpf_program__attach_kprobe_opts(const struct bpf_program *prog, const char *func_name, const struct bpf_kprobe_opts *opts); @@ -297,11 +345,11 @@ struct bpf_uprobe_opts { #define bpf_uprobe_opts__last_field retprobe LIBBPF_API struct bpf_link * -bpf_program__attach_uprobe(struct bpf_program *prog, bool retprobe, +bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe, pid_t pid, const char *binary_path, size_t func_offset); LIBBPF_API struct bpf_link * -bpf_program__attach_uprobe_opts(struct bpf_program *prog, pid_t pid, +bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, const char *binary_path, size_t func_offset, const struct bpf_uprobe_opts *opts); @@ -314,35 +362,35 @@ struct bpf_tracepoint_opts { #define bpf_tracepoint_opts__last_field bpf_cookie LIBBPF_API struct bpf_link * -bpf_program__attach_tracepoint(struct bpf_program *prog, +bpf_program__attach_tracepoint(const struct bpf_program *prog, const char *tp_category, const char *tp_name); LIBBPF_API struct bpf_link * -bpf_program__attach_tracepoint_opts(struct bpf_program *prog, +bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, const char *tp_category, const char *tp_name, const struct bpf_tracepoint_opts *opts); LIBBPF_API struct bpf_link * -bpf_program__attach_raw_tracepoint(struct bpf_program *prog, +bpf_program__attach_raw_tracepoint(const struct bpf_program *prog, const char *tp_name); LIBBPF_API struct bpf_link * -bpf_program__attach_trace(struct bpf_program *prog); +bpf_program__attach_trace(const struct bpf_program *prog); LIBBPF_API struct bpf_link * -bpf_program__attach_lsm(struct bpf_program *prog); +bpf_program__attach_lsm(const struct bpf_program *prog); LIBBPF_API struct bpf_link * -bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd); +bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd); LIBBPF_API struct bpf_link * -bpf_program__attach_netns(struct bpf_program *prog, int netns_fd); +bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd); LIBBPF_API struct bpf_link * -bpf_program__attach_xdp(struct bpf_program *prog, int ifindex); +bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex); LIBBPF_API struct bpf_link * -bpf_program__attach_freplace(struct bpf_program *prog, +bpf_program__attach_freplace(const struct bpf_program *prog, int target_fd, const char *attach_func_name); struct bpf_map; -LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map); +LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map); struct bpf_iter_attach_opts { size_t sz; /* size of this struct for forward/backward compatibility */ @@ -352,11 +400,9 @@ struct bpf_iter_attach_opts { #define bpf_iter_attach_opts__last_field link_info_len LIBBPF_API struct bpf_link * -bpf_program__attach_iter(struct bpf_program *prog, +bpf_program__attach_iter(const struct bpf_program *prog, const struct bpf_iter_attach_opts *opts); -struct bpf_insn; - /* * Libbpf allows callers to adjust BPF programs before being loaded * into kernel. One program in an object file can be transformed into @@ -385,7 +431,7 @@ struct bpf_insn; * one instance. In this case bpf_program__fd(prog) is equal to * bpf_program__nth_fd(prog, 0). */ - +LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions") struct bpf_prog_prep_result { /* * If not NULL, load new instruction array. @@ -414,9 +460,11 @@ typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n, struct bpf_insn *insns, int insns_cnt, struct bpf_prog_prep_result *res); +LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions") LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance, bpf_program_prep_t prep); +LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated") LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n); /* @@ -478,9 +526,13 @@ struct bpf_map_def { unsigned int map_flags; }; -/* - * The 'struct bpf_map' in include/linux/bpf.h is internal to the kernel, - * so no need to worry about a name clash. +/** + * @brief **bpf_object__find_map_by_name()** returns BPF map of + * the given name, if it exists within the passed BPF object + * @param obj BPF object + * @param name name of the BPF map + * @return BPF map instance, if such map exists within the BPF object; + * or NULL otherwise. */ LIBBPF_API struct bpf_map * bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name); @@ -495,18 +547,28 @@ bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name); LIBBPF_API struct bpf_map * bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset); +LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_map() instead") +struct bpf_map *bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj); LIBBPF_API struct bpf_map * -bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj); +bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map); + #define bpf_object__for_each_map(pos, obj) \ - for ((pos) = bpf_map__next(NULL, (obj)); \ + for ((pos) = bpf_object__next_map((obj), NULL); \ (pos) != NULL; \ - (pos) = bpf_map__next((pos), (obj))) + (pos) = bpf_object__next_map((obj), (pos))) #define bpf_map__for_each bpf_object__for_each_map +LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_map() instead") +struct bpf_map *bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj); LIBBPF_API struct bpf_map * -bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj); +bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map); -/* get/set map FD */ +/** + * @brief **bpf_map__fd()** gets the file descriptor of the passed + * BPF map + * @param map the BPF map instance + * @return the file descriptor; or -EINVAL in case of an error + */ LIBBPF_API int bpf_map__fd(const struct bpf_map *map); LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd); /* get map definition */ @@ -538,6 +600,9 @@ LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map); /* get/set map if_index */ LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map); LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex); +/* get/set map map_extra flags */ +LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map); +LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra); typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *); LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv, @@ -547,6 +612,14 @@ LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map, const void *data, size_t size); LIBBPF_API const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize); LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map); + +/** + * @brief **bpf_map__is_internal()** tells the caller whether or not the + * passed map is a special map created by libbpf automatically for things like + * global variables, __ksym externs, Kconfig values, etc + * @param map the bpf_map + * @return true, if the map is an internal map; false, otherwise + */ LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map); LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path); LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map); @@ -558,6 +631,38 @@ LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path); LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd); LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map); +/** + * @brief **libbpf_get_error()** extracts the error code from the passed + * pointer + * @param ptr pointer returned from libbpf API function + * @return error code; or 0 if no error occured + * + * Many libbpf API functions which return pointers have logic to encode error + * codes as pointers, and do not return NULL. Meaning **libbpf_get_error()** + * should be used on the return value from these functions immediately after + * calling the API function, with no intervening calls that could clobber the + * `errno` variable. Consult the individual functions documentation to verify + * if this logic applies should be used. + * + * For these API functions, if `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)` + * is enabled, NULL is returned on error instead. + * + * If ptr is NULL, then errno should be already set by the failing + * API, because libbpf never returns NULL on success and it now always + * sets errno on error. + * + * Example usage: + * + * struct perf_buffer *pb; + * + * pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES, &opts); + * err = libbpf_get_error(pb); + * if (err) { + * pb = NULL; + * fprintf(stderr, "failed to open perf buffer: %d\n", err); + * goto cleanup; + * } + */ LIBBPF_API long libbpf_get_error(const void *ptr); struct bpf_prog_load_attr { @@ -822,9 +927,10 @@ bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear); LIBBPF_API void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear); -/* - * A helper function to get the number of possible CPUs before looking up - * per-CPU maps. Negative errno is returned on failure. +/** + * @brief **libbpf_num_possible_cpus()** is a helper function to get the + * number of possible CPUs that the host kernel supports and expects. + * @return number of possible CPUs; or error code on failure * * Example usage: * @@ -834,7 +940,6 @@ bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear); * } * long values[ncpus]; * bpf_map_lookup_elem(per_cpu_map_fd, key, values); - * */ LIBBPF_API int libbpf_num_possible_cpus(void); @@ -854,7 +959,7 @@ struct bpf_object_skeleton { size_t sz; /* size of this struct, for forward/backward compatibility */ const char *name; - void *data; + const void *data; size_t data_sz; struct bpf_object **obj; |