2 * Common eBPF ELF object loading operations.
4 * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
5 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
6 * Copyright (C) 2015 Huawei Inc.
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation;
11 * version 2.1 of the License (not later!)
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this program; if not, see <http://www.gnu.org/licenses>
30 #include <asm/unistd.h>
31 #include <linux/kernel.h>
32 #include <linux/bpf.h>
33 #include <linux/list.h>
40 #define __printf(a, b) __attribute__((format(printf, a, b)))
43 static int __base_pr(const char *format
, ...)
48 va_start(args
, format
);
49 err
= vfprintf(stderr
, format
, args
);
54 static __printf(1, 2) libbpf_print_fn_t __pr_warning
= __base_pr
;
55 static __printf(1, 2) libbpf_print_fn_t __pr_info
= __base_pr
;
56 static __printf(1, 2) libbpf_print_fn_t __pr_debug
;
58 #define __pr(func, fmt, ...) \
61 (func)("libbpf: " fmt, ##__VA_ARGS__); \
64 #define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__)
65 #define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__)
66 #define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__)
68 void libbpf_set_print(libbpf_print_fn_t warn
,
69 libbpf_print_fn_t info
,
70 libbpf_print_fn_t debug
)
77 #define STRERR_BUFSIZE 128
79 #define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START)
80 #define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c)
81 #define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
83 static const char *libbpf_strerror_table
[NR_ERRNO
] = {
84 [ERRCODE_OFFSET(LIBELF
)] = "Something wrong in libelf",
85 [ERRCODE_OFFSET(FORMAT
)] = "BPF object format invalid",
86 [ERRCODE_OFFSET(KVERSION
)] = "'version' section incorrect or lost",
87 [ERRCODE_OFFSET(ENDIAN
)] = "Endian mismatch",
88 [ERRCODE_OFFSET(INTERNAL
)] = "Internal error in libbpf",
89 [ERRCODE_OFFSET(RELOC
)] = "Relocation failed",
90 [ERRCODE_OFFSET(VERIFY
)] = "Kernel verifier blocks program loading",
91 [ERRCODE_OFFSET(PROG2BIG
)] = "Program too big",
92 [ERRCODE_OFFSET(KVER
)] = "Incorrect kernel version",
93 [ERRCODE_OFFSET(PROGTYPE
)] = "Kernel doesn't support this program type",
96 int libbpf_strerror(int err
, char *buf
, size_t size
)
101 err
= err
> 0 ? err
: -err
;
103 if (err
< __LIBBPF_ERRNO__START
) {
106 ret
= strerror_r(err
, buf
, size
);
107 buf
[size
- 1] = '\0';
111 if (err
< __LIBBPF_ERRNO__END
) {
114 msg
= libbpf_strerror_table
[ERRNO_OFFSET(err
)];
115 snprintf(buf
, size
, "%s", msg
);
116 buf
[size
- 1] = '\0';
120 snprintf(buf
, size
, "Unknown libbpf error %d", err
);
121 buf
[size
- 1] = '\0';
125 #define CHECK_ERR(action, err, out) do { \
132 /* Copied from tools/perf/util/util.h */
134 # define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
138 # define zclose(fd) ({ \
141 ___err = close((fd)); \
146 #ifdef HAVE_LIBELF_MMAP_SUPPORT
147 # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP
149 # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ
153 * bpf_prog should be a better name but it has been used in
157 /* Index in elf obj file, for relocation use. */
160 struct bpf_insn
*insns
;
162 enum bpf_prog_type type
;
174 bpf_program_prep_t preprocessor
;
176 struct bpf_object
*obj
;
178 bpf_program_clear_priv_t clear_priv
;
184 struct bpf_map_def def
;
186 bpf_map_clear_priv_t clear_priv
;
189 static LIST_HEAD(bpf_objects_list
);
195 struct bpf_program
*programs
;
197 struct bpf_map
*maps
;
203 * Information when doing elf related work. Only valid if fd
222 * All loaded bpf_object is linked in a list, which is
223 * hidden to caller. bpf_objects__<func> handlers deal with
226 struct list_head list
;
229 #define obj_elf_valid(o) ((o)->efile.elf)
231 static void bpf_program__unload(struct bpf_program
*prog
)
239 * If the object is opened but the program was never loaded,
240 * it is possible that prog->instances.nr == -1.
242 if (prog
->instances
.nr
> 0) {
243 for (i
= 0; i
< prog
->instances
.nr
; i
++)
244 zclose(prog
->instances
.fds
[i
]);
245 } else if (prog
->instances
.nr
!= -1) {
246 pr_warning("Internal error: instances.nr is %d\n",
250 prog
->instances
.nr
= -1;
251 zfree(&prog
->instances
.fds
);
254 static void bpf_program__exit(struct bpf_program
*prog
)
259 if (prog
->clear_priv
)
260 prog
->clear_priv(prog
, prog
->priv
);
263 prog
->clear_priv
= NULL
;
265 bpf_program__unload(prog
);
266 zfree(&prog
->section_name
);
268 zfree(&prog
->reloc_desc
);
276 bpf_program__init(void *data
, size_t size
, char *name
, int idx
,
277 struct bpf_program
*prog
)
279 if (size
< sizeof(struct bpf_insn
)) {
280 pr_warning("corrupted section '%s'\n", name
);
284 bzero(prog
, sizeof(*prog
));
286 prog
->section_name
= strdup(name
);
287 if (!prog
->section_name
) {
288 pr_warning("failed to alloc name for prog %s\n",
293 prog
->insns
= malloc(size
);
295 pr_warning("failed to alloc insns for %s\n", name
);
298 prog
->insns_cnt
= size
/ sizeof(struct bpf_insn
);
299 memcpy(prog
->insns
, data
,
300 prog
->insns_cnt
* sizeof(struct bpf_insn
));
302 prog
->instances
.fds
= NULL
;
303 prog
->instances
.nr
= -1;
304 prog
->type
= BPF_PROG_TYPE_KPROBE
;
308 bpf_program__exit(prog
);
313 bpf_object__add_program(struct bpf_object
*obj
, void *data
, size_t size
,
316 struct bpf_program prog
, *progs
;
319 err
= bpf_program__init(data
, size
, name
, idx
, &prog
);
323 progs
= obj
->programs
;
324 nr_progs
= obj
->nr_programs
;
326 progs
= realloc(progs
, sizeof(progs
[0]) * (nr_progs
+ 1));
329 * In this case the original obj->programs
330 * is still valid, so don't need special treat for
331 * bpf_close_object().
333 pr_warning("failed to alloc a new program '%s'\n",
335 bpf_program__exit(&prog
);
339 pr_debug("found program %s\n", prog
.section_name
);
340 obj
->programs
= progs
;
341 obj
->nr_programs
= nr_progs
+ 1;
343 progs
[nr_progs
] = prog
;
347 static struct bpf_object
*bpf_object__new(const char *path
,
351 struct bpf_object
*obj
;
353 obj
= calloc(1, sizeof(struct bpf_object
) + strlen(path
) + 1);
355 pr_warning("alloc memory failed for %s\n", path
);
356 return ERR_PTR(-ENOMEM
);
359 strcpy(obj
->path
, path
);
363 * Caller of this function should also calls
364 * bpf_object__elf_finish() after data collection to return
365 * obj_buf to user. If not, we should duplicate the buffer to
366 * avoid user freeing them before elf finish.
368 obj
->efile
.obj_buf
= obj_buf
;
369 obj
->efile
.obj_buf_sz
= obj_buf_sz
;
370 obj
->efile
.maps_shndx
= -1;
374 INIT_LIST_HEAD(&obj
->list
);
375 list_add(&obj
->list
, &bpf_objects_list
);
379 static void bpf_object__elf_finish(struct bpf_object
*obj
)
381 if (!obj_elf_valid(obj
))
384 if (obj
->efile
.elf
) {
385 elf_end(obj
->efile
.elf
);
386 obj
->efile
.elf
= NULL
;
388 obj
->efile
.symbols
= NULL
;
390 zfree(&obj
->efile
.reloc
);
391 obj
->efile
.nr_reloc
= 0;
392 zclose(obj
->efile
.fd
);
393 obj
->efile
.obj_buf
= NULL
;
394 obj
->efile
.obj_buf_sz
= 0;
397 static int bpf_object__elf_init(struct bpf_object
*obj
)
402 if (obj_elf_valid(obj
)) {
403 pr_warning("elf init: internal error\n");
404 return -LIBBPF_ERRNO__LIBELF
;
407 if (obj
->efile
.obj_buf_sz
> 0) {
409 * obj_buf should have been validated by
410 * bpf_object__open_buffer().
412 obj
->efile
.elf
= elf_memory(obj
->efile
.obj_buf
,
413 obj
->efile
.obj_buf_sz
);
415 obj
->efile
.fd
= open(obj
->path
, O_RDONLY
);
416 if (obj
->efile
.fd
< 0) {
417 pr_warning("failed to open %s: %s\n", obj
->path
,
422 obj
->efile
.elf
= elf_begin(obj
->efile
.fd
,
423 LIBBPF_ELF_C_READ_MMAP
,
427 if (!obj
->efile
.elf
) {
428 pr_warning("failed to open %s as ELF file\n",
430 err
= -LIBBPF_ERRNO__LIBELF
;
434 if (!gelf_getehdr(obj
->efile
.elf
, &obj
->efile
.ehdr
)) {
435 pr_warning("failed to get EHDR from %s\n",
437 err
= -LIBBPF_ERRNO__FORMAT
;
440 ep
= &obj
->efile
.ehdr
;
442 if ((ep
->e_type
!= ET_REL
) || (ep
->e_machine
!= 0)) {
443 pr_warning("%s is not an eBPF object file\n",
445 err
= -LIBBPF_ERRNO__FORMAT
;
451 bpf_object__elf_finish(obj
);
456 bpf_object__check_endianness(struct bpf_object
*obj
)
458 static unsigned int const endian
= 1;
460 switch (obj
->efile
.ehdr
.e_ident
[EI_DATA
]) {
462 /* We are big endian, BPF obj is little endian. */
463 if (*(unsigned char const *)&endian
!= 1)
468 /* We are little endian, BPF obj is big endian. */
469 if (*(unsigned char const *)&endian
!= 0)
473 return -LIBBPF_ERRNO__ENDIAN
;
479 pr_warning("Error: endianness mismatch.\n");
480 return -LIBBPF_ERRNO__ENDIAN
;
484 bpf_object__init_license(struct bpf_object
*obj
,
485 void *data
, size_t size
)
487 memcpy(obj
->license
, data
,
488 min(size
, sizeof(obj
->license
) - 1));
489 pr_debug("license of %s is %s\n", obj
->path
, obj
->license
);
494 bpf_object__init_kversion(struct bpf_object
*obj
,
495 void *data
, size_t size
)
499 if (size
!= sizeof(kver
)) {
500 pr_warning("invalid kver section in %s\n", obj
->path
);
501 return -LIBBPF_ERRNO__FORMAT
;
503 memcpy(&kver
, data
, sizeof(kver
));
504 obj
->kern_version
= kver
;
505 pr_debug("kernel version of %s is %x\n", obj
->path
,
511 bpf_object__init_maps(struct bpf_object
*obj
, void *data
,
517 nr_maps
= size
/ sizeof(struct bpf_map_def
);
518 if (!data
|| !nr_maps
) {
519 pr_debug("%s doesn't need map definition\n",
524 pr_debug("maps in %s: %zd bytes\n", obj
->path
, size
);
526 obj
->maps
= calloc(nr_maps
, sizeof(obj
->maps
[0]));
528 pr_warning("alloc maps for object failed\n");
531 obj
->nr_maps
= nr_maps
;
533 for (i
= 0; i
< nr_maps
; i
++) {
534 struct bpf_map_def
*def
= &obj
->maps
[i
].def
;
537 * fill all fd with -1 so won't close incorrect
538 * fd (fd=0 is stdin) when failure (zclose won't close
541 obj
->maps
[i
].fd
= -1;
543 /* Save map definition into obj->maps */
544 *def
= ((struct bpf_map_def
*)data
)[i
];
550 bpf_object__init_maps_name(struct bpf_object
*obj
)
553 Elf_Data
*symbols
= obj
->efile
.symbols
;
555 if (!symbols
|| obj
->efile
.maps_shndx
< 0)
558 for (i
= 0; i
< symbols
->d_size
/ sizeof(GElf_Sym
); i
++) {
561 const char *map_name
;
563 if (!gelf_getsym(symbols
, i
, &sym
))
565 if (sym
.st_shndx
!= obj
->efile
.maps_shndx
)
568 map_name
= elf_strptr(obj
->efile
.elf
,
569 obj
->efile
.strtabidx
,
571 map_idx
= sym
.st_value
/ sizeof(struct bpf_map_def
);
572 if (map_idx
>= obj
->nr_maps
) {
573 pr_warning("index of map \"%s\" is buggy: %zu > %zu\n",
574 map_name
, map_idx
, obj
->nr_maps
);
577 obj
->maps
[map_idx
].name
= strdup(map_name
);
578 if (!obj
->maps
[map_idx
].name
) {
579 pr_warning("failed to alloc map name\n");
582 pr_debug("map %zu is \"%s\"\n", map_idx
,
583 obj
->maps
[map_idx
].name
);
588 static int bpf_object__elf_collect(struct bpf_object
*obj
)
590 Elf
*elf
= obj
->efile
.elf
;
591 GElf_Ehdr
*ep
= &obj
->efile
.ehdr
;
593 int idx
= 0, err
= 0;
595 /* Elf is corrupted/truncated, avoid calling elf_strptr. */
596 if (!elf_rawdata(elf_getscn(elf
, ep
->e_shstrndx
), NULL
)) {
597 pr_warning("failed to get e_shstrndx from %s\n",
599 return -LIBBPF_ERRNO__FORMAT
;
602 while ((scn
= elf_nextscn(elf
, scn
)) != NULL
) {
608 if (gelf_getshdr(scn
, &sh
) != &sh
) {
609 pr_warning("failed to get section header from %s\n",
611 err
= -LIBBPF_ERRNO__FORMAT
;
615 name
= elf_strptr(elf
, ep
->e_shstrndx
, sh
.sh_name
);
617 pr_warning("failed to get section name from %s\n",
619 err
= -LIBBPF_ERRNO__FORMAT
;
623 data
= elf_getdata(scn
, 0);
625 pr_warning("failed to get section data from %s(%s)\n",
627 err
= -LIBBPF_ERRNO__FORMAT
;
630 pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n",
631 name
, (unsigned long)data
->d_size
,
632 (int)sh
.sh_link
, (unsigned long)sh
.sh_flags
,
635 if (strcmp(name
, "license") == 0)
636 err
= bpf_object__init_license(obj
,
639 else if (strcmp(name
, "version") == 0)
640 err
= bpf_object__init_kversion(obj
,
643 else if (strcmp(name
, "maps") == 0) {
644 err
= bpf_object__init_maps(obj
, data
->d_buf
,
646 obj
->efile
.maps_shndx
= idx
;
647 } else if (sh
.sh_type
== SHT_SYMTAB
) {
648 if (obj
->efile
.symbols
) {
649 pr_warning("bpf: multiple SYMTAB in %s\n",
651 err
= -LIBBPF_ERRNO__FORMAT
;
653 obj
->efile
.symbols
= data
;
654 obj
->efile
.strtabidx
= sh
.sh_link
;
656 } else if ((sh
.sh_type
== SHT_PROGBITS
) &&
657 (sh
.sh_flags
& SHF_EXECINSTR
) &&
658 (data
->d_size
> 0)) {
659 err
= bpf_object__add_program(obj
, data
->d_buf
,
660 data
->d_size
, name
, idx
);
662 char errmsg
[STRERR_BUFSIZE
];
664 strerror_r(-err
, errmsg
, sizeof(errmsg
));
665 pr_warning("failed to alloc program %s (%s): %s",
666 name
, obj
->path
, errmsg
);
668 } else if (sh
.sh_type
== SHT_REL
) {
669 void *reloc
= obj
->efile
.reloc
;
670 int nr_reloc
= obj
->efile
.nr_reloc
+ 1;
672 reloc
= realloc(reloc
,
673 sizeof(*obj
->efile
.reloc
) * nr_reloc
);
675 pr_warning("realloc failed\n");
678 int n
= nr_reloc
- 1;
680 obj
->efile
.reloc
= reloc
;
681 obj
->efile
.nr_reloc
= nr_reloc
;
683 obj
->efile
.reloc
[n
].shdr
= sh
;
684 obj
->efile
.reloc
[n
].data
= data
;
691 if (!obj
->efile
.strtabidx
|| obj
->efile
.strtabidx
>= idx
) {
692 pr_warning("Corrupted ELF file: index of strtab invalid\n");
693 return LIBBPF_ERRNO__FORMAT
;
695 if (obj
->efile
.maps_shndx
>= 0)
696 err
= bpf_object__init_maps_name(obj
);
701 static struct bpf_program
*
702 bpf_object__find_prog_by_idx(struct bpf_object
*obj
, int idx
)
704 struct bpf_program
*prog
;
707 for (i
= 0; i
< obj
->nr_programs
; i
++) {
708 prog
= &obj
->programs
[i
];
709 if (prog
->idx
== idx
)
716 bpf_program__collect_reloc(struct bpf_program
*prog
,
717 size_t nr_maps
, GElf_Shdr
*shdr
,
718 Elf_Data
*data
, Elf_Data
*symbols
,
723 pr_debug("collecting relocating info for: '%s'\n",
725 nrels
= shdr
->sh_size
/ shdr
->sh_entsize
;
727 prog
->reloc_desc
= malloc(sizeof(*prog
->reloc_desc
) * nrels
);
728 if (!prog
->reloc_desc
) {
729 pr_warning("failed to alloc memory in relocation\n");
732 prog
->nr_reloc
= nrels
;
734 for (i
= 0; i
< nrels
; i
++) {
737 unsigned int insn_idx
;
738 struct bpf_insn
*insns
= prog
->insns
;
741 if (!gelf_getrel(data
, i
, &rel
)) {
742 pr_warning("relocation: failed to get %d reloc\n", i
);
743 return -LIBBPF_ERRNO__FORMAT
;
746 if (!gelf_getsym(symbols
,
747 GELF_R_SYM(rel
.r_info
),
749 pr_warning("relocation: symbol %"PRIx64
" not found\n",
750 GELF_R_SYM(rel
.r_info
));
751 return -LIBBPF_ERRNO__FORMAT
;
754 if (sym
.st_shndx
!= maps_shndx
) {
755 pr_warning("Program '%s' contains non-map related relo data pointing to section %u\n",
756 prog
->section_name
, sym
.st_shndx
);
757 return -LIBBPF_ERRNO__RELOC
;
760 insn_idx
= rel
.r_offset
/ sizeof(struct bpf_insn
);
761 pr_debug("relocation: insn_idx=%u\n", insn_idx
);
763 if (insns
[insn_idx
].code
!= (BPF_LD
| BPF_IMM
| BPF_DW
)) {
764 pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n",
765 insn_idx
, insns
[insn_idx
].code
);
766 return -LIBBPF_ERRNO__RELOC
;
769 map_idx
= sym
.st_value
/ sizeof(struct bpf_map_def
);
770 if (map_idx
>= nr_maps
) {
771 pr_warning("bpf relocation: map_idx %d large than %d\n",
772 (int)map_idx
, (int)nr_maps
- 1);
773 return -LIBBPF_ERRNO__RELOC
;
776 prog
->reloc_desc
[i
].insn_idx
= insn_idx
;
777 prog
->reloc_desc
[i
].map_idx
= map_idx
;
783 bpf_object__create_maps(struct bpf_object
*obj
)
787 for (i
= 0; i
< obj
->nr_maps
; i
++) {
788 struct bpf_map_def
*def
= &obj
->maps
[i
].def
;
789 int *pfd
= &obj
->maps
[i
].fd
;
791 *pfd
= bpf_create_map(def
->type
,
799 pr_warning("failed to create map: %s\n",
801 for (j
= 0; j
< i
; j
++)
802 zclose(obj
->maps
[j
].fd
);
805 pr_debug("create map: fd=%d\n", *pfd
);
812 bpf_program__relocate(struct bpf_program
*prog
, struct bpf_object
*obj
)
816 if (!prog
|| !prog
->reloc_desc
)
819 for (i
= 0; i
< prog
->nr_reloc
; i
++) {
820 int insn_idx
, map_idx
;
821 struct bpf_insn
*insns
= prog
->insns
;
823 insn_idx
= prog
->reloc_desc
[i
].insn_idx
;
824 map_idx
= prog
->reloc_desc
[i
].map_idx
;
826 if (insn_idx
>= (int)prog
->insns_cnt
) {
827 pr_warning("relocation out of range: '%s'\n",
829 return -LIBBPF_ERRNO__RELOC
;
831 insns
[insn_idx
].src_reg
= BPF_PSEUDO_MAP_FD
;
832 insns
[insn_idx
].imm
= obj
->maps
[map_idx
].fd
;
835 zfree(&prog
->reloc_desc
);
842 bpf_object__relocate(struct bpf_object
*obj
)
844 struct bpf_program
*prog
;
848 for (i
= 0; i
< obj
->nr_programs
; i
++) {
849 prog
= &obj
->programs
[i
];
851 err
= bpf_program__relocate(prog
, obj
);
853 pr_warning("failed to relocate '%s'\n",
861 static int bpf_object__collect_reloc(struct bpf_object
*obj
)
865 if (!obj_elf_valid(obj
)) {
866 pr_warning("Internal error: elf object is closed\n");
867 return -LIBBPF_ERRNO__INTERNAL
;
870 for (i
= 0; i
< obj
->efile
.nr_reloc
; i
++) {
871 GElf_Shdr
*shdr
= &obj
->efile
.reloc
[i
].shdr
;
872 Elf_Data
*data
= obj
->efile
.reloc
[i
].data
;
873 int idx
= shdr
->sh_info
;
874 struct bpf_program
*prog
;
875 size_t nr_maps
= obj
->nr_maps
;
877 if (shdr
->sh_type
!= SHT_REL
) {
878 pr_warning("internal error at %d\n", __LINE__
);
879 return -LIBBPF_ERRNO__INTERNAL
;
882 prog
= bpf_object__find_prog_by_idx(obj
, idx
);
884 pr_warning("relocation failed: no %d section\n",
886 return -LIBBPF_ERRNO__RELOC
;
889 err
= bpf_program__collect_reloc(prog
, nr_maps
,
892 obj
->efile
.maps_shndx
);
900 load_program(enum bpf_prog_type type
, struct bpf_insn
*insns
,
901 int insns_cnt
, char *license
, u32 kern_version
, int *pfd
)
906 if (!insns
|| !insns_cnt
)
909 log_buf
= malloc(BPF_LOG_BUF_SIZE
);
911 pr_warning("Alloc log buffer for bpf loader error, continue without log\n");
913 ret
= bpf_load_program(type
, insns
, insns_cnt
, license
,
914 kern_version
, log_buf
, BPF_LOG_BUF_SIZE
);
922 ret
= -LIBBPF_ERRNO__LOAD
;
923 pr_warning("load bpf program failed: %s\n", strerror(errno
));
925 if (log_buf
&& log_buf
[0] != '\0') {
926 ret
= -LIBBPF_ERRNO__VERIFY
;
927 pr_warning("-- BEGIN DUMP LOG ---\n");
928 pr_warning("\n%s\n", log_buf
);
929 pr_warning("-- END LOG --\n");
930 } else if (insns_cnt
>= BPF_MAXINSNS
) {
931 pr_warning("Program too large (%d insns), at most %d insns\n",
932 insns_cnt
, BPF_MAXINSNS
);
933 ret
= -LIBBPF_ERRNO__PROG2BIG
;
935 /* Wrong program type? */
936 if (type
!= BPF_PROG_TYPE_KPROBE
) {
939 fd
= bpf_load_program(BPF_PROG_TYPE_KPROBE
, insns
,
940 insns_cnt
, license
, kern_version
,
944 ret
= -LIBBPF_ERRNO__PROGTYPE
;
950 ret
= -LIBBPF_ERRNO__KVER
;
959 bpf_program__load(struct bpf_program
*prog
,
960 char *license
, u32 kern_version
)
964 if (prog
->instances
.nr
< 0 || !prog
->instances
.fds
) {
965 if (prog
->preprocessor
) {
966 pr_warning("Internal error: can't load program '%s'\n",
968 return -LIBBPF_ERRNO__INTERNAL
;
971 prog
->instances
.fds
= malloc(sizeof(int));
972 if (!prog
->instances
.fds
) {
973 pr_warning("Not enough memory for BPF fds\n");
976 prog
->instances
.nr
= 1;
977 prog
->instances
.fds
[0] = -1;
980 if (!prog
->preprocessor
) {
981 if (prog
->instances
.nr
!= 1) {
982 pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n",
983 prog
->section_name
, prog
->instances
.nr
);
985 err
= load_program(prog
->type
, prog
->insns
, prog
->insns_cnt
,
986 license
, kern_version
, &fd
);
988 prog
->instances
.fds
[0] = fd
;
992 for (i
= 0; i
< prog
->instances
.nr
; i
++) {
993 struct bpf_prog_prep_result result
;
994 bpf_program_prep_t preprocessor
= prog
->preprocessor
;
996 bzero(&result
, sizeof(result
));
997 err
= preprocessor(prog
, i
, prog
->insns
,
998 prog
->insns_cnt
, &result
);
1000 pr_warning("Preprocessing the %dth instance of program '%s' failed\n",
1001 i
, prog
->section_name
);
1005 if (!result
.new_insn_ptr
|| !result
.new_insn_cnt
) {
1006 pr_debug("Skip loading the %dth instance of program '%s'\n",
1007 i
, prog
->section_name
);
1008 prog
->instances
.fds
[i
] = -1;
1014 err
= load_program(prog
->type
, result
.new_insn_ptr
,
1015 result
.new_insn_cnt
,
1016 license
, kern_version
, &fd
);
1019 pr_warning("Loading the %dth instance of program '%s' failed\n",
1020 i
, prog
->section_name
);
1026 prog
->instances
.fds
[i
] = fd
;
1030 pr_warning("failed to load program '%s'\n",
1031 prog
->section_name
);
1032 zfree(&prog
->insns
);
1033 prog
->insns_cnt
= 0;
1038 bpf_object__load_progs(struct bpf_object
*obj
)
1043 for (i
= 0; i
< obj
->nr_programs
; i
++) {
1044 err
= bpf_program__load(&obj
->programs
[i
],
1053 static int bpf_object__validate(struct bpf_object
*obj
)
1055 if (obj
->kern_version
== 0) {
1056 pr_warning("%s doesn't provide kernel version\n",
1058 return -LIBBPF_ERRNO__KVERSION
;
1063 static struct bpf_object
*
1064 __bpf_object__open(const char *path
, void *obj_buf
, size_t obj_buf_sz
)
1066 struct bpf_object
*obj
;
1069 if (elf_version(EV_CURRENT
) == EV_NONE
) {
1070 pr_warning("failed to init libelf for %s\n", path
);
1071 return ERR_PTR(-LIBBPF_ERRNO__LIBELF
);
1074 obj
= bpf_object__new(path
, obj_buf
, obj_buf_sz
);
1078 CHECK_ERR(bpf_object__elf_init(obj
), err
, out
);
1079 CHECK_ERR(bpf_object__check_endianness(obj
), err
, out
);
1080 CHECK_ERR(bpf_object__elf_collect(obj
), err
, out
);
1081 CHECK_ERR(bpf_object__collect_reloc(obj
), err
, out
);
1082 CHECK_ERR(bpf_object__validate(obj
), err
, out
);
1084 bpf_object__elf_finish(obj
);
1087 bpf_object__close(obj
);
1088 return ERR_PTR(err
);
1091 struct bpf_object
*bpf_object__open(const char *path
)
1093 /* param validation */
1097 pr_debug("loading %s\n", path
);
1099 return __bpf_object__open(path
, NULL
, 0);
1102 struct bpf_object
*bpf_object__open_buffer(void *obj_buf
,
1108 /* param validation */
1109 if (!obj_buf
|| obj_buf_sz
<= 0)
1113 snprintf(tmp_name
, sizeof(tmp_name
), "%lx-%lx",
1114 (unsigned long)obj_buf
,
1115 (unsigned long)obj_buf_sz
);
1116 tmp_name
[sizeof(tmp_name
) - 1] = '\0';
1119 pr_debug("loading object '%s' from buffer\n",
1122 return __bpf_object__open(name
, obj_buf
, obj_buf_sz
);
1125 int bpf_object__unload(struct bpf_object
*obj
)
1132 for (i
= 0; i
< obj
->nr_maps
; i
++)
1133 zclose(obj
->maps
[i
].fd
);
1135 for (i
= 0; i
< obj
->nr_programs
; i
++)
1136 bpf_program__unload(&obj
->programs
[i
]);
1141 int bpf_object__load(struct bpf_object
*obj
)
1149 pr_warning("object should not be loaded twice\n");
1155 CHECK_ERR(bpf_object__create_maps(obj
), err
, out
);
1156 CHECK_ERR(bpf_object__relocate(obj
), err
, out
);
1157 CHECK_ERR(bpf_object__load_progs(obj
), err
, out
);
1161 bpf_object__unload(obj
);
1162 pr_warning("failed to load object '%s'\n", obj
->path
);
1166 void bpf_object__close(struct bpf_object
*obj
)
1173 bpf_object__elf_finish(obj
);
1174 bpf_object__unload(obj
);
1176 for (i
= 0; i
< obj
->nr_maps
; i
++) {
1177 zfree(&obj
->maps
[i
].name
);
1178 if (obj
->maps
[i
].clear_priv
)
1179 obj
->maps
[i
].clear_priv(&obj
->maps
[i
],
1181 obj
->maps
[i
].priv
= NULL
;
1182 obj
->maps
[i
].clear_priv
= NULL
;
1187 if (obj
->programs
&& obj
->nr_programs
) {
1188 for (i
= 0; i
< obj
->nr_programs
; i
++)
1189 bpf_program__exit(&obj
->programs
[i
]);
1191 zfree(&obj
->programs
);
1193 list_del(&obj
->list
);
1198 bpf_object__next(struct bpf_object
*prev
)
1200 struct bpf_object
*next
;
1203 next
= list_first_entry(&bpf_objects_list
,
1207 next
= list_next_entry(prev
, list
);
1209 /* Empty list is noticed here so don't need checking on entry. */
1210 if (&next
->list
== &bpf_objects_list
)
1216 const char *bpf_object__name(struct bpf_object
*obj
)
1218 return obj
? obj
->path
: ERR_PTR(-EINVAL
);
1221 unsigned int bpf_object__kversion(struct bpf_object
*obj
)
1223 return obj
? obj
->kern_version
: 0;
1226 struct bpf_program
*
1227 bpf_program__next(struct bpf_program
*prev
, struct bpf_object
*obj
)
1235 return &obj
->programs
[0];
1237 if (prev
->obj
!= obj
) {
1238 pr_warning("error: program handler doesn't match object\n");
1242 idx
= (prev
- obj
->programs
) + 1;
1243 if (idx
>= obj
->nr_programs
)
1245 return &obj
->programs
[idx
];
1248 int bpf_program__set_priv(struct bpf_program
*prog
, void *priv
,
1249 bpf_program_clear_priv_t clear_priv
)
1251 if (prog
->priv
&& prog
->clear_priv
)
1252 prog
->clear_priv(prog
, prog
->priv
);
1255 prog
->clear_priv
= clear_priv
;
1259 void *bpf_program__priv(struct bpf_program
*prog
)
1261 return prog
? prog
->priv
: ERR_PTR(-EINVAL
);
1264 const char *bpf_program__title(struct bpf_program
*prog
, bool needs_copy
)
1268 title
= prog
->section_name
;
1270 title
= strdup(title
);
1272 pr_warning("failed to strdup program title\n");
1273 return ERR_PTR(-ENOMEM
);
1280 int bpf_program__fd(struct bpf_program
*prog
)
1282 return bpf_program__nth_fd(prog
, 0);
1285 int bpf_program__set_prep(struct bpf_program
*prog
, int nr_instances
,
1286 bpf_program_prep_t prep
)
1290 if (nr_instances
<= 0 || !prep
)
1293 if (prog
->instances
.nr
> 0 || prog
->instances
.fds
) {
1294 pr_warning("Can't set pre-processor after loading\n");
1298 instances_fds
= malloc(sizeof(int) * nr_instances
);
1299 if (!instances_fds
) {
1300 pr_warning("alloc memory failed for fds\n");
1304 /* fill all fd with -1 */
1305 memset(instances_fds
, -1, sizeof(int) * nr_instances
);
1307 prog
->instances
.nr
= nr_instances
;
1308 prog
->instances
.fds
= instances_fds
;
1309 prog
->preprocessor
= prep
;
1313 int bpf_program__nth_fd(struct bpf_program
*prog
, int n
)
1317 if (n
>= prog
->instances
.nr
|| n
< 0) {
1318 pr_warning("Can't get the %dth fd from program %s: only %d instances\n",
1319 n
, prog
->section_name
, prog
->instances
.nr
);
1323 fd
= prog
->instances
.fds
[n
];
1325 pr_warning("%dth instance of program '%s' is invalid\n",
1326 n
, prog
->section_name
);
1333 static void bpf_program__set_type(struct bpf_program
*prog
,
1334 enum bpf_prog_type type
)
1339 int bpf_program__set_tracepoint(struct bpf_program
*prog
)
1343 bpf_program__set_type(prog
, BPF_PROG_TYPE_TRACEPOINT
);
1347 int bpf_program__set_kprobe(struct bpf_program
*prog
)
1351 bpf_program__set_type(prog
, BPF_PROG_TYPE_KPROBE
);
1355 static bool bpf_program__is_type(struct bpf_program
*prog
,
1356 enum bpf_prog_type type
)
1358 return prog
? (prog
->type
== type
) : false;
1361 bool bpf_program__is_tracepoint(struct bpf_program
*prog
)
1363 return bpf_program__is_type(prog
, BPF_PROG_TYPE_TRACEPOINT
);
1366 bool bpf_program__is_kprobe(struct bpf_program
*prog
)
1368 return bpf_program__is_type(prog
, BPF_PROG_TYPE_KPROBE
);
1371 int bpf_map__fd(struct bpf_map
*map
)
1373 return map
? map
->fd
: -EINVAL
;
1376 const struct bpf_map_def
*bpf_map__def(struct bpf_map
*map
)
1378 return map
? &map
->def
: ERR_PTR(-EINVAL
);
1381 const char *bpf_map__name(struct bpf_map
*map
)
1383 return map
? map
->name
: NULL
;
1386 int bpf_map__set_priv(struct bpf_map
*map
, void *priv
,
1387 bpf_map_clear_priv_t clear_priv
)
1393 if (map
->clear_priv
)
1394 map
->clear_priv(map
, map
->priv
);
1398 map
->clear_priv
= clear_priv
;
1402 void *bpf_map__priv(struct bpf_map
*map
)
1404 return map
? map
->priv
: ERR_PTR(-EINVAL
);
1408 bpf_map__next(struct bpf_map
*prev
, struct bpf_object
*obj
)
1411 struct bpf_map
*s
, *e
;
1413 if (!obj
|| !obj
->maps
)
1417 e
= obj
->maps
+ obj
->nr_maps
;
1422 if ((prev
< s
) || (prev
>= e
)) {
1423 pr_warning("error in %s: map handler doesn't belong to object\n",
1428 idx
= (prev
- obj
->maps
) + 1;
1429 if (idx
>= obj
->nr_maps
)
1431 return &obj
->maps
[idx
];
1435 bpf_object__find_map_by_name(struct bpf_object
*obj
, const char *name
)
1437 struct bpf_map
*pos
;
1439 bpf_map__for_each(pos
, obj
) {
1440 if (pos
->name
&& !strcmp(pos
->name
, name
))