diff options
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 159 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.h | 20 | ||||
| -rw-r--r-- | tools/perf/tests/llvm.c | 2 | ||||
| -rw-r--r-- | tools/perf/util/bpf-loader.c | 33 | ||||
| -rw-r--r-- | tools/perf/util/parse-events.c | 4 |
5 files changed, 159 insertions, 59 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 9f3c8cf9249b..07b492d3dfaa 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -61,6 +61,60 @@ void libbpf_set_print(libbpf_print_fn_t warn, __pr_debug = debug; } +#define STRERR_BUFSIZE 128 + +#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START) +#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c) +#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START) + +static const char *libbpf_strerror_table[NR_ERRNO] = { + [ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf", + [ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid", + [ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost", + [ERRCODE_OFFSET(ENDIAN)] = "Endian missmatch", + [ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf", + [ERRCODE_OFFSET(RELOC)] = "Relocation failed", + [ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading", + [ERRCODE_OFFSET(PROG2BIG)] = "Program too big", + [ERRCODE_OFFSET(KVER)] = "Incorrect kernel version", +}; + +int libbpf_strerror(int err, char *buf, size_t size) +{ + if (!buf || !size) + return -1; + + err = err > 0 ? err : -err; + + if (err < __LIBBPF_ERRNO__START) { + int ret; + + ret = strerror_r(err, buf, size); + buf[size - 1] = '\0'; + return ret; + } + + if (err < __LIBBPF_ERRNO__END) { + const char *msg; + + msg = libbpf_strerror_table[ERRNO_OFFSET(err)]; + snprintf(buf, size, "%s", msg); + buf[size - 1] = '\0'; + return 0; + } + + snprintf(buf, size, "Unknown libbpf error %d", err); + buf[size - 1] = '\0'; + return -1; +} + +#define CHECK_ERR(action, err, out) do { \ + err = action; \ + if (err) \ + goto out; \ +} while(0) + + /* Copied from tools/perf/util/util.h */ #ifndef zfree # define zfree(ptr) ({ free(*ptr); *ptr = NULL; }) @@ -258,7 +312,7 @@ static struct bpf_object *bpf_object__new(const char *path, obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1); if (!obj) { pr_warning("alloc memory failed for %s\n", path); - return NULL; + return ERR_PTR(-ENOMEM); } strcpy(obj->path, path); @@ -305,7 +359,7 @@ static int bpf_object__elf_init(struct bpf_object *obj) if (obj_elf_valid(obj)) { pr_warning("elf init: internal error\n"); - return -EEXIST; + return -LIBBPF_ERRNO__LIBELF; } if (obj->efile.obj_buf_sz > 0) { @@ -331,14 +385,14 @@ static int bpf_object__elf_init(struct bpf_object *obj) if (!obj->efile.elf) { pr_warning("failed to open %s as ELF file\n", obj->path); - err = -EINVAL; + err = -LIBBPF_ERRNO__LIBELF; goto errout; } if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) { pr_warning("failed to get EHDR from %s\n", obj->path); - err = -EINVAL; + err = -LIBBPF_ERRNO__FORMAT; goto errout; } ep = &obj->efile.ehdr; @@ -346,7 +400,7 @@ static int bpf_object__elf_init(struct bpf_object *obj) if ((ep->e_type != ET_REL) || (ep->e_machine != 0)) { pr_warning("%s is not an eBPF object file\n", obj->path); - err = -EINVAL; + err = -LIBBPF_ERRNO__FORMAT; goto errout; } @@ -374,14 +428,14 @@ bpf_object__check_endianness(struct bpf_object *obj) goto mismatch; break; default: - return -EINVAL; + return -LIBBPF_ERRNO__ENDIAN; } return 0; mismatch: pr_warning("Error: endianness mismatch.\n"); - return -EINVAL; + return -LIBBPF_ERRNO__ENDIAN; } static int @@ -402,7 +456,7 @@ bpf_object__init_kversion(struct bpf_object *obj, if (size != sizeof(kver)) { pr_warning("invalid kver section in %s\n", obj->path); - return -EINVAL; + return -LIBBPF_ERRNO__FORMAT; } memcpy(&kver, data, sizeof(kver)); obj->kern_version = kver; @@ -444,7 +498,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) { pr_warning("failed to get e_shstrndx from %s\n", obj->path); - return -EINVAL; + return -LIBBPF_ERRNO__FORMAT; } while ((scn = elf_nextscn(elf, scn)) != NULL) { @@ -456,7 +510,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) if (gelf_getshdr(scn, &sh) != &sh) { pr_warning("failed to get section header from %s\n", obj->path); - err = -EINVAL; + err = -LIBBPF_ERRNO__FORMAT; goto out; } @@ -464,7 +518,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) if (!name) { pr_warning("failed to get section name from %s\n", obj->path); - err = -EINVAL; + err = -LIBBPF_ERRNO__FORMAT; goto out; } @@ -472,7 +526,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) if (!data) { pr_warning("failed to get section data from %s(%s)\n", name, obj->path); - err = -EINVAL; + err = -LIBBPF_ERRNO__FORMAT; goto out; } pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n", @@ -495,7 +549,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) if (obj->efile.symbols) { pr_warning("bpf: multiple SYMTAB in %s\n", obj->path); - err = -EEXIST; + err = -LIBBPF_ERRNO__FORMAT; } else obj->efile.symbols = data; } else if ((sh.sh_type == SHT_PROGBITS) && @@ -504,7 +558,8 @@ static int bpf_object__elf_collect(struct bpf_object *obj) err = bpf_object__add_program(obj, data->d_buf, data->d_size, name, idx); if (err) { - char errmsg[128]; + char errmsg[STRERR_BUFSIZE]; + strerror_r(-err, errmsg, sizeof(errmsg)); pr_warning("failed to alloc program %s (%s): %s", name, obj->path, errmsg); @@ -576,7 +631,7 @@ bpf_program__collect_reloc(struct bpf_program *prog, if (!gelf_getrel(data, i, &rel)) { pr_warning("relocation: failed to get %d reloc\n", i); - return -EINVAL; + return -LIBBPF_ERRNO__FORMAT; } insn_idx = rel.r_offset / sizeof(struct bpf_insn); @@ -587,20 +642,20 @@ bpf_program__collect_reloc(struct bpf_program *prog, &sym)) { pr_warning("relocation: symbol %"PRIx64" not found\n", GELF_R_SYM(rel.r_info)); - return -EINVAL; + return -LIBBPF_ERRNO__FORMAT; } if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) { pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n", insn_idx, insns[insn_idx].code); - return -EINVAL; + return -LIBBPF_ERRNO__RELOC; } map_idx = sym.st_value / sizeof(struct bpf_map_def); if (map_idx >= nr_maps) { pr_warning("bpf relocation: map_idx %d large than %d\n", (int)map_idx, (int)nr_maps - 1); - return -EINVAL; + return -LIBBPF_ERRNO__RELOC; } prog->reloc_desc[i].insn_idx = insn_idx; @@ -683,7 +738,7 @@ bpf_program__relocate(struct bpf_program *prog, int *map_fds) if (insn_idx >= (int)prog->insns_cnt) { pr_warning("relocation out of range: '%s'\n", prog->section_name); - return -ERANGE; + return -LIBBPF_ERRNO__RELOC; } insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD; insns[insn_idx].imm = map_fds[map_idx]; @@ -721,7 +776,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj) if (!obj_elf_valid(obj)) { pr_warning("Internal error: elf object is closed\n"); - return -EINVAL; + return -LIBBPF_ERRNO__INTERNAL; } for (i = 0; i < obj->efile.nr_reloc; i++) { @@ -734,21 +789,21 @@ static int bpf_object__collect_reloc(struct bpf_object *obj) if (shdr->sh_type != SHT_REL) { pr_warning("internal error at %d\n", __LINE__); - return -EINVAL; + return -LIBBPF_ERRNO__INTERNAL; } prog = bpf_object__find_prog_by_idx(obj, idx); if (!prog) { pr_warning("relocation failed: no %d section\n", idx); - return -ENOENT; + return -LIBBPF_ERRNO__RELOC; } err = bpf_program__collect_reloc(prog, nr_maps, shdr, data, obj->efile.symbols); if (err) - return -EINVAL; + return err; } return 0; } @@ -777,13 +832,23 @@ load_program(struct bpf_insn *insns, int insns_cnt, goto out; } - ret = -EINVAL; + ret = -LIBBPF_ERRNO__LOAD; pr_warning("load bpf program failed: %s\n", strerror(errno)); - if (log_buf) { + if (log_buf && log_buf[0] != '\0') { + ret = -LIBBPF_ERRNO__VERIFY; pr_warning("-- BEGIN DUMP LOG ---\n"); pr_warning("\n%s\n", log_buf); pr_warning("-- END LOG --\n"); + } else { + if (insns_cnt >= BPF_MAXINSNS) { + pr_warning("Program too large (%d insns), at most %d insns\n", + insns_cnt, BPF_MAXINSNS); + ret = -LIBBPF_ERRNO__PROG2BIG; + } else if (log_buf) { + pr_warning("log buffer is empty\n"); + ret = -LIBBPF_ERRNO__KVER; + } } out: @@ -831,7 +896,7 @@ static int bpf_object__validate(struct bpf_object *obj) if (obj->kern_version == 0) { pr_warning("%s doesn't provide kernel version\n", obj->path); - return -EINVAL; + return -LIBBPF_ERRNO__KVERSION; } return 0; } @@ -840,32 +905,28 @@ static struct bpf_object * __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz) { struct bpf_object *obj; + int err; if (elf_version(EV_CURRENT) == EV_NONE) { pr_warning("failed to init libelf for %s\n", path); - return NULL; + return ERR_PTR(-LIBBPF_ERRNO__LIBELF); } obj = bpf_object__new(path, obj_buf, obj_buf_sz); - if (!obj) - return NULL; + if (IS_ERR(obj)) + return obj; - if (bpf_object__elf_init(obj)) - goto out; - if (bpf_object__check_endianness(obj)) - goto out; - if (bpf_object__elf_collect(obj)) - goto out; - if (bpf_object__collect_reloc(obj)) - goto out; - if (bpf_object__validate(obj)) - goto out; + CHECK_ERR(bpf_object__elf_init(obj), err, out); + CHECK_ERR(bpf_object__check_endianness(obj), err, out); + CHECK_ERR(bpf_object__elf_collect(obj), err, out); + CHECK_ERR(bpf_object__collect_reloc(obj), err, out); + CHECK_ERR(bpf_object__validate(obj), err, out); bpf_object__elf_finish(obj); return obj; out: bpf_object__close(obj); - return NULL; + return ERR_PTR(err); } struct bpf_object *bpf_object__open(const char *path) @@ -922,6 +983,8 @@ int bpf_object__unload(struct bpf_object *obj) int bpf_object__load(struct bpf_object *obj) { + int err; + if (!obj) return -EINVAL; @@ -931,18 +994,16 @@ int bpf_object__load(struct bpf_object *obj) } obj->loaded = true; - if (bpf_object__create_maps(obj)) - goto out; - if (bpf_object__relocate(obj)) - goto out; - if (bpf_object__load_progs(obj)) - goto out; + + CHECK_ERR(bpf_object__create_maps(obj), err, out); + CHECK_ERR(bpf_object__relocate(obj), err, out); + CHECK_ERR(bpf_object__load_progs(obj), err, out); return 0; out: bpf_object__unload(obj); pr_warning("failed to load object '%s'\n", obj->path); - return -EINVAL; + return err; } void bpf_object__close(struct bpf_object *obj) @@ -990,7 +1051,7 @@ const char * bpf_object__get_name(struct bpf_object *obj) { if (!obj) - return NULL; + return ERR_PTR(-EINVAL); return obj->path; } @@ -1043,7 +1104,7 @@ const char *bpf_program__title(struct bpf_program *prog, bool needs_copy) title = strdup(title); if (!title) { pr_warning("failed to strdup program title\n"); - return NULL; + return ERR_PTR(-ENOMEM); } } diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index bc80af03c6f4..30a40e9fa503 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -10,6 +10,26 @@ #include <stdio.h> #include <stdbool.h> +#include <linux/err.h> + +enum libbpf_errno { + __LIBBPF_ERRNO__START = 4000, + + /* Something wrong in libelf */ + LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START, + LIBBPF_ERRNO__FORMAT, /* BPF object format invalid */ + LIBBPF_ERRNO__KVERSION, /* Incorrect or no 'version' section */ + LIBBPF_ERRNO__ENDIAN, /* Endian missmatch */ + LIBBPF_ERRNO__INTERNAL, /* Internal error in libbpf */ + LIBBPF_ERRNO__RELOC, /* Relocation failed */ + LIBBPF_ERRNO__LOAD, /* Load program failure for unknown reason */ + LIBBPF_ERRNO__VERIFY, /* Kernel verifier blocks program loading */ + LIBBPF_ERRNO__PROG2BIG, /* Program too big */ + LIBBPF_ERRNO__KVER, /* Incorrect kernel version */ + __LIBBPF_ERRNO__END, +}; + +int libbpf_strerror(int err, char *buf, size_t size); /* * In include/linux/compiler-gcc.h, __printf is defined. However diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c index 512d3620e9f9..8f713f6d32f3 100644 --- a/tools/perf/tests/llvm.c +++ b/tools/perf/tests/llvm.c @@ -27,7 +27,7 @@ static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz) struct bpf_object *obj; obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, NULL); - if (!obj) + if (IS_ERR(obj)) return -1; bpf_object__close(obj); return 0; diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index 0c5d174245bb..c46256b1f5fd 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -59,9 +59,9 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source) } else obj = bpf_object__open(filename); - if (!obj) { + if (IS_ERR(obj)) { pr_debug("bpf: failed to load %s\n", filename); - return ERR_PTR(-EINVAL); + return obj; } return obj; @@ -96,9 +96,9 @@ config_bpf_program(struct bpf_program *prog) int err; config_str = bpf_program__title(prog, false); - if (!config_str) { + if (IS_ERR(config_str)) { pr_debug("bpf: unable to get title for program\n"); - return -EINVAL; + return PTR_ERR(config_str); } priv = calloc(sizeof(*priv), 1); @@ -308,13 +308,34 @@ int bpf__foreach_tev(struct bpf_object *obj, return 0; } +static int +bpf_loader_strerror(int err, char *buf, size_t size) +{ + char sbuf[STRERR_BUFSIZE]; + const char *msg; + + if (!buf || !size) + return -1; + + err = err > 0 ? err : -err; + + if (err >= __LIBBPF_ERRNO__START) + return libbpf_strerror(err, buf, size); + + msg = strerror_r(err, sbuf, sizeof(sbuf)); + snprintf(buf, size, "%s", msg); + buf[size - 1] = '\0'; + return 0; +} + #define bpf__strerror_head(err, buf, size) \ char sbuf[STRERR_BUFSIZE], *emsg;\ if (!size)\ return 0;\ if (err < 0)\ err = -err;\ - emsg = strerror_r(err, sbuf, sizeof(sbuf));\ + bpf_loader_strerror(err, sbuf, sizeof(sbuf));\ + emsg = sbuf;\ switch (err) {\ default:\ scnprintf(buf, size, "%s", emsg);\ @@ -345,8 +366,6 @@ int bpf__strerror_load(struct bpf_object *obj __maybe_unused, int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); - bpf__strerror_entry(EINVAL, "%s: Are you root and runing a CONFIG_BPF_SYSCALL kernel?", - emsg) bpf__strerror_end(buf, size); return 0; } diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index bee60583839a..c75b25d5e28c 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -632,11 +632,11 @@ int parse_events_load_bpf(struct parse_events_evlist *data, struct bpf_object *obj; obj = bpf__prepare_load(bpf_file_name, source); - if (IS_ERR(obj) || !obj) { + if (IS_ERR(obj)) { char errbuf[BUFSIZ]; int err; - err = obj ? PTR_ERR(obj) : -EINVAL; + err = PTR_ERR(obj); if (err == -ENOTSUP) snprintf(errbuf, sizeof(errbuf), |