From b4b7ff4b08e691656c9d77c758fc355833128ac0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 20 Jan 2016 14:01:31 -0300 Subject: Linux-libre 4.4-gnu --- tools/lib/bpf/.gitignore | 2 +- tools/lib/bpf/Makefile | 13 ++-- tools/lib/bpf/libbpf.c | 171 +++++++++++++++++++++++++++++++++-------------- tools/lib/bpf/libbpf.h | 23 ++++++- 4 files changed, 151 insertions(+), 58 deletions(-) (limited to 'tools/lib/bpf') diff --git a/tools/lib/bpf/.gitignore b/tools/lib/bpf/.gitignore index 812aeedae..f81e549dd 100644 --- a/tools/lib/bpf/.gitignore +++ b/tools/lib/bpf/.gitignore @@ -1,2 +1,2 @@ libbpf_version.h -FEATURE-DUMP +FEATURE-DUMP.libbpf diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile index f68d23a0b..a3caaf3ea 100644 --- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -64,8 +64,9 @@ srctree := $(patsubst %/,%,$(dir $(srctree))) #$(info Determined 'srctree' to be $(srctree)) endif -FEATURE_DISPLAY = libelf libelf-getphdrnum libelf-mmap bpf -FEATURE_TESTS = libelf bpf +FEATURE_USER = .libbpf +FEATURE_TESTS = libelf libelf-getphdrnum libelf-mmap bpf +FEATURE_DISPLAY = libelf bpf INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/arch/$(ARCH)/include/uapi -I$(srctree)/include/uapi FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES) @@ -122,8 +123,10 @@ endif # the same command line setup. MAKEOVERRIDES= +all: + export srctree OUTPUT CC LD CFLAGS V -build := -f $(srctree)/tools/build/Makefile.build dir=. obj +include $(srctree)/tools/build/Makefile.include BPF_IN := $(OUTPUT)libbpf-in.o LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE)) @@ -132,7 +135,7 @@ CMD_TARGETS = $(LIB_FILE) TARGETS = $(CMD_TARGETS) -all: $(VERSION_FILES) all_cmd +all: fixdep $(VERSION_FILES) all_cmd all_cmd: $(CMD_TARGETS) @@ -177,7 +180,7 @@ config-clean: clean: $(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so $(VERSION_FILES) .*.d \ $(RM) LIBBPF-CFLAGS - $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP + $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 4252fc22f..e176bad19 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) @@ -990,10 +1051,18 @@ const char * bpf_object__get_name(struct bpf_object *obj) { if (!obj) - return NULL; + return ERR_PTR(-EINVAL); return obj->path; } +unsigned int +bpf_object__get_kversion(struct bpf_object *obj) +{ + if (!obj) + return 0; + return obj->kern_version; +} + struct bpf_program * bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) { @@ -1034,16 +1103,16 @@ int bpf_program__get_private(struct bpf_program *prog, void **ppriv) return 0; } -const char *bpf_program__title(struct bpf_program *prog, bool dup) +const char *bpf_program__title(struct bpf_program *prog, bool needs_copy) { const char *title; title = prog->section_name; - if (dup) { + if (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 f16170c95..c9a9aef28 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -10,6 +10,26 @@ #include #include +#include + +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 @@ -36,6 +56,7 @@ void bpf_object__close(struct bpf_object *object); int bpf_object__load(struct bpf_object *obj); int bpf_object__unload(struct bpf_object *obj); const char *bpf_object__get_name(struct bpf_object *obj); +unsigned int bpf_object__get_kversion(struct bpf_object *obj); struct bpf_object *bpf_object__next(struct bpf_object *prev); #define bpf_object__for_each_safe(pos, tmp) \ @@ -63,7 +84,7 @@ int bpf_program__set_private(struct bpf_program *prog, void *priv, int bpf_program__get_private(struct bpf_program *prog, void **ppriv); -const char *bpf_program__title(struct bpf_program *prog, bool dup); +const char *bpf_program__title(struct bpf_program *prog, bool needs_copy); int bpf_program__fd(struct bpf_program *prog); -- cgit v1.2.3-54-g00ecf