1 // SPDX-License-Identifier: GPL-2.0
10 #include "demangle-java.h"
11 #include "demangle-rust.h"
15 #include "sane_ctype.h"
16 #include <symbol/kallsyms.h>
19 #define EM_AARCH64 183 /* ARM 64 bit */
22 typedef Elf64_Nhdr GElf_Nhdr
;
24 #ifdef HAVE_CPLUS_DEMANGLE_SUPPORT
25 extern char *cplus_demangle(const char *, int);
27 static inline char *bfd_demangle(void __maybe_unused
*v
, const char *c
, int i
)
29 return cplus_demangle(c
, i
);
33 static inline char *bfd_demangle(void __maybe_unused
*v
,
34 const char __maybe_unused
*c
,
40 #define PACKAGE 'perf'
45 #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT
46 static int elf_getphdrnum(Elf
*elf
, size_t *dst
)
51 ehdr
= gelf_getehdr(elf
, &gehdr
);
61 #ifndef HAVE_ELF_GETSHDRSTRNDX_SUPPORT
62 static int elf_getshdrstrndx(Elf
*elf __maybe_unused
, size_t *dst __maybe_unused
)
64 pr_err("%s: update your libelf to > 0.140, this one lacks elf_getshdrstrndx().\n", __func__
);
69 #ifndef NT_GNU_BUILD_ID
70 #define NT_GNU_BUILD_ID 3
74 * elf_symtab__for_each_symbol - iterate thru all the symbols
76 * @syms: struct elf_symtab instance to iterate
78 * @sym: GElf_Sym iterator
80 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
81 for (idx = 0, gelf_getsym(syms, idx, &sym);\
83 idx++, gelf_getsym(syms, idx, &sym))
85 static inline uint8_t elf_sym__type(const GElf_Sym
*sym
)
87 return GELF_ST_TYPE(sym
->st_info
);
91 #define STT_GNU_IFUNC 10
94 static inline int elf_sym__is_function(const GElf_Sym
*sym
)
96 return (elf_sym__type(sym
) == STT_FUNC
||
97 elf_sym__type(sym
) == STT_GNU_IFUNC
) &&
99 sym
->st_shndx
!= SHN_UNDEF
;
102 static inline bool elf_sym__is_object(const GElf_Sym
*sym
)
104 return elf_sym__type(sym
) == STT_OBJECT
&&
106 sym
->st_shndx
!= SHN_UNDEF
;
109 static inline int elf_sym__is_label(const GElf_Sym
*sym
)
111 return elf_sym__type(sym
) == STT_NOTYPE
&&
113 sym
->st_shndx
!= SHN_UNDEF
&&
114 sym
->st_shndx
!= SHN_ABS
;
117 static bool elf_sym__filter(GElf_Sym
*sym
)
119 return elf_sym__is_function(sym
) || elf_sym__is_object(sym
);
122 static inline const char *elf_sym__name(const GElf_Sym
*sym
,
123 const Elf_Data
*symstrs
)
125 return symstrs
->d_buf
+ sym
->st_name
;
128 static inline const char *elf_sec__name(const GElf_Shdr
*shdr
,
129 const Elf_Data
*secstrs
)
131 return secstrs
->d_buf
+ shdr
->sh_name
;
134 static inline int elf_sec__is_text(const GElf_Shdr
*shdr
,
135 const Elf_Data
*secstrs
)
137 return strstr(elf_sec__name(shdr
, secstrs
), "text") != NULL
;
140 static inline bool elf_sec__is_data(const GElf_Shdr
*shdr
,
141 const Elf_Data
*secstrs
)
143 return strstr(elf_sec__name(shdr
, secstrs
), "data") != NULL
;
146 static bool elf_sec__filter(GElf_Shdr
*shdr
, Elf_Data
*secstrs
)
148 return elf_sec__is_text(shdr
, secstrs
) ||
149 elf_sec__is_data(shdr
, secstrs
);
152 static size_t elf_addr_to_index(Elf
*elf
, GElf_Addr addr
)
158 while ((sec
= elf_nextscn(elf
, sec
)) != NULL
) {
159 gelf_getshdr(sec
, &shdr
);
161 if ((addr
>= shdr
.sh_addr
) &&
162 (addr
< (shdr
.sh_addr
+ shdr
.sh_size
)))
171 Elf_Scn
*elf_section_by_name(Elf
*elf
, GElf_Ehdr
*ep
,
172 GElf_Shdr
*shp
, const char *name
, size_t *idx
)
177 /* Elf is corrupted/truncated, avoid calling elf_strptr. */
178 if (!elf_rawdata(elf_getscn(elf
, ep
->e_shstrndx
), NULL
))
181 while ((sec
= elf_nextscn(elf
, sec
)) != NULL
) {
184 gelf_getshdr(sec
, shp
);
185 str
= elf_strptr(elf
, ep
->e_shstrndx
, shp
->sh_name
);
186 if (str
&& !strcmp(name
, str
)) {
197 static bool want_demangle(bool is_kernel_sym
)
199 return is_kernel_sym
? symbol_conf
.demangle_kernel
: symbol_conf
.demangle
;
202 static char *demangle_sym(struct dso
*dso
, int kmodule
, const char *elf_name
)
204 int demangle_flags
= verbose
> 0 ? (DMGL_PARAMS
| DMGL_ANSI
) : DMGL_NO_OPTS
;
205 char *demangled
= NULL
;
208 * We need to figure out if the object was created from C++ sources
209 * DWARF DW_compile_unit has this, but we don't always have access
212 if (!want_demangle(dso
->kernel
|| kmodule
))
215 demangled
= bfd_demangle(NULL
, elf_name
, demangle_flags
);
216 if (demangled
== NULL
)
217 demangled
= java_demangle_sym(elf_name
, JAVA_DEMANGLE_NORET
);
218 else if (rust_is_mangled(demangled
))
220 * Input to Rust demangling is the BFD-demangled
221 * name which it Rust-demangles in place.
223 rust_demangle_sym(demangled
);
228 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
229 for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
231 ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
233 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
234 for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
236 ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
239 * We need to check if we have a .dynsym, so that we can handle the
240 * .plt, synthesizing its symbols, that aren't on the symtabs (be it
241 * .dynsym or .symtab).
242 * And always look at the original dso, not at debuginfo packages, that
243 * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
245 int dso__synthesize_plt_symbols(struct dso
*dso
, struct symsrc
*ss
)
247 uint32_t nr_rel_entries
, idx
;
249 u64 plt_offset
, plt_header_size
, plt_entry_size
;
252 GElf_Shdr shdr_rel_plt
, shdr_dynsym
;
253 Elf_Data
*reldata
, *syms
, *symstrs
;
254 Elf_Scn
*scn_plt_rel
, *scn_symstrs
, *scn_dynsym
;
257 char sympltname
[1024];
259 int nr
= 0, symidx
, err
= 0;
267 scn_dynsym
= ss
->dynsym
;
268 shdr_dynsym
= ss
->dynshdr
;
269 dynsym_idx
= ss
->dynsym_idx
;
271 if (scn_dynsym
== NULL
)
274 scn_plt_rel
= elf_section_by_name(elf
, &ehdr
, &shdr_rel_plt
,
276 if (scn_plt_rel
== NULL
) {
277 scn_plt_rel
= elf_section_by_name(elf
, &ehdr
, &shdr_rel_plt
,
279 if (scn_plt_rel
== NULL
)
285 if (shdr_rel_plt
.sh_link
!= dynsym_idx
)
288 if (elf_section_by_name(elf
, &ehdr
, &shdr_plt
, ".plt", NULL
) == NULL
)
292 * Fetch the relocation section to find the idxes to the GOT
293 * and the symbols in the .dynsym they refer to.
295 reldata
= elf_getdata(scn_plt_rel
, NULL
);
299 syms
= elf_getdata(scn_dynsym
, NULL
);
303 scn_symstrs
= elf_getscn(elf
, shdr_dynsym
.sh_link
);
304 if (scn_symstrs
== NULL
)
307 symstrs
= elf_getdata(scn_symstrs
, NULL
);
311 if (symstrs
->d_size
== 0)
314 nr_rel_entries
= shdr_rel_plt
.sh_size
/ shdr_rel_plt
.sh_entsize
;
315 plt_offset
= shdr_plt
.sh_offset
;
316 switch (ehdr
.e_machine
) {
318 plt_header_size
= 20;
323 plt_header_size
= 32;
327 default: /* FIXME: s390/alpha/mips/parisc/poperpc/sh/sparc/xtensa need to be checked */
328 plt_header_size
= shdr_plt
.sh_entsize
;
329 plt_entry_size
= shdr_plt
.sh_entsize
;
332 plt_offset
+= plt_header_size
;
334 if (shdr_rel_plt
.sh_type
== SHT_RELA
) {
335 GElf_Rela pos_mem
, *pos
;
337 elf_section__for_each_rela(reldata
, pos
, pos_mem
, idx
,
339 const char *elf_name
= NULL
;
340 char *demangled
= NULL
;
341 symidx
= GELF_R_SYM(pos
->r_info
);
342 gelf_getsym(syms
, symidx
, &sym
);
344 elf_name
= elf_sym__name(&sym
, symstrs
);
345 demangled
= demangle_sym(dso
, 0, elf_name
);
346 if (demangled
!= NULL
)
347 elf_name
= demangled
;
348 snprintf(sympltname
, sizeof(sympltname
),
352 f
= symbol__new(plt_offset
, plt_entry_size
,
353 STB_GLOBAL
, STT_FUNC
, sympltname
);
357 plt_offset
+= plt_entry_size
;
358 symbols__insert(&dso
->symbols
, f
);
361 } else if (shdr_rel_plt
.sh_type
== SHT_REL
) {
362 GElf_Rel pos_mem
, *pos
;
363 elf_section__for_each_rel(reldata
, pos
, pos_mem
, idx
,
365 const char *elf_name
= NULL
;
366 char *demangled
= NULL
;
367 symidx
= GELF_R_SYM(pos
->r_info
);
368 gelf_getsym(syms
, symidx
, &sym
);
370 elf_name
= elf_sym__name(&sym
, symstrs
);
371 demangled
= demangle_sym(dso
, 0, elf_name
);
372 if (demangled
!= NULL
)
373 elf_name
= demangled
;
374 snprintf(sympltname
, sizeof(sympltname
),
378 f
= symbol__new(plt_offset
, plt_entry_size
,
379 STB_GLOBAL
, STT_FUNC
, sympltname
);
383 plt_offset
+= plt_entry_size
;
384 symbols__insert(&dso
->symbols
, f
);
393 pr_debug("%s: problems reading %s PLT info.\n",
394 __func__
, dso
->long_name
);
398 char *dso__demangle_sym(struct dso
*dso
, int kmodule
, const char *elf_name
)
400 return demangle_sym(dso
, kmodule
, elf_name
);
404 * Align offset to 4 bytes as needed for note name and descriptor data.
406 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
408 static int elf_read_build_id(Elf
*elf
, void *bf
, size_t size
)
418 if (size
< BUILD_ID_SIZE
)
425 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
426 pr_err("%s: cannot get elf header.\n", __func__
);
431 * Check following sections for notes:
432 * '.note.gnu.build-id'
434 * '.note' (VDSO specific)
437 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
438 ".note.gnu.build-id", NULL
);
442 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
447 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
456 data
= elf_getdata(sec
, NULL
);
461 while (ptr
< (data
->d_buf
+ data
->d_size
)) {
462 GElf_Nhdr
*nhdr
= ptr
;
463 size_t namesz
= NOTE_ALIGN(nhdr
->n_namesz
),
464 descsz
= NOTE_ALIGN(nhdr
->n_descsz
);
467 ptr
+= sizeof(*nhdr
);
470 if (nhdr
->n_type
== NT_GNU_BUILD_ID
&&
471 nhdr
->n_namesz
== sizeof("GNU")) {
472 if (memcmp(name
, "GNU", sizeof("GNU")) == 0) {
473 size_t sz
= min(size
, descsz
);
475 memset(bf
+ sz
, 0, size
- sz
);
487 int filename__read_build_id(const char *filename
, void *bf
, size_t size
)
492 if (size
< BUILD_ID_SIZE
)
495 fd
= open(filename
, O_RDONLY
);
499 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
501 pr_debug2("%s: cannot read %s ELF file.\n", __func__
, filename
);
505 err
= elf_read_build_id(elf
, bf
, size
);
514 int sysfs__read_build_id(const char *filename
, void *build_id
, size_t size
)
518 if (size
< BUILD_ID_SIZE
)
521 fd
= open(filename
, O_RDONLY
);
528 size_t namesz
, descsz
;
530 if (read(fd
, &nhdr
, sizeof(nhdr
)) != sizeof(nhdr
))
533 namesz
= NOTE_ALIGN(nhdr
.n_namesz
);
534 descsz
= NOTE_ALIGN(nhdr
.n_descsz
);
535 if (nhdr
.n_type
== NT_GNU_BUILD_ID
&&
536 nhdr
.n_namesz
== sizeof("GNU")) {
537 if (read(fd
, bf
, namesz
) != (ssize_t
)namesz
)
539 if (memcmp(bf
, "GNU", sizeof("GNU")) == 0) {
540 size_t sz
= min(descsz
, size
);
541 if (read(fd
, build_id
, sz
) == (ssize_t
)sz
) {
542 memset(build_id
+ sz
, 0, size
- sz
);
546 } else if (read(fd
, bf
, descsz
) != (ssize_t
)descsz
)
549 int n
= namesz
+ descsz
;
551 if (n
> (int)sizeof(bf
)) {
553 pr_debug("%s: truncating reading of build id in sysfs file %s: n_namesz=%u, n_descsz=%u.\n",
554 __func__
, filename
, nhdr
.n_namesz
, nhdr
.n_descsz
);
556 if (read(fd
, bf
, n
) != n
)
565 int filename__read_debuglink(const char *filename
, char *debuglink
,
576 fd
= open(filename
, O_RDONLY
);
580 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
582 pr_debug2("%s: cannot read %s ELF file.\n", __func__
, filename
);
590 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
591 pr_err("%s: cannot get elf header.\n", __func__
);
595 sec
= elf_section_by_name(elf
, &ehdr
, &shdr
,
596 ".gnu_debuglink", NULL
);
600 data
= elf_getdata(sec
, NULL
);
604 /* the start of this section is a zero-terminated string */
605 strncpy(debuglink
, data
->d_buf
, size
);
617 static int dso__swap_init(struct dso
*dso
, unsigned char eidata
)
619 static unsigned int const endian
= 1;
621 dso
->needs_swap
= DSO_SWAP__NO
;
625 /* We are big endian, DSO is little endian. */
626 if (*(unsigned char const *)&endian
!= 1)
627 dso
->needs_swap
= DSO_SWAP__YES
;
631 /* We are little endian, DSO is big endian. */
632 if (*(unsigned char const *)&endian
!= 0)
633 dso
->needs_swap
= DSO_SWAP__YES
;
637 pr_err("unrecognized DSO data encoding %d\n", eidata
);
644 bool symsrc__possibly_runtime(struct symsrc
*ss
)
646 return ss
->dynsym
|| ss
->opdsec
;
649 bool symsrc__has_symtab(struct symsrc
*ss
)
651 return ss
->symtab
!= NULL
;
654 void symsrc__destroy(struct symsrc
*ss
)
661 bool __weak
elf__needs_adjust_symbols(GElf_Ehdr ehdr
)
663 return ehdr
.e_type
== ET_EXEC
|| ehdr
.e_type
== ET_REL
;
666 int symsrc__init(struct symsrc
*ss
, struct dso
*dso
, const char *name
,
667 enum dso_binary_type type
)
674 if (dso__needs_decompress(dso
)) {
675 fd
= dso__decompress_kmodule_fd(dso
, name
);
679 type
= dso
->symtab_type
;
681 fd
= open(name
, O_RDONLY
);
683 dso
->load_errno
= errno
;
688 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
690 pr_debug("%s: cannot read %s ELF file.\n", __func__
, name
);
691 dso
->load_errno
= DSO_LOAD_ERRNO__INVALID_ELF
;
695 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
696 dso
->load_errno
= DSO_LOAD_ERRNO__INVALID_ELF
;
697 pr_debug("%s: cannot get elf header.\n", __func__
);
701 if (dso__swap_init(dso
, ehdr
.e_ident
[EI_DATA
])) {
702 dso
->load_errno
= DSO_LOAD_ERRNO__INTERNAL_ERROR
;
706 /* Always reject images with a mismatched build-id: */
707 if (dso
->has_build_id
&& !symbol_conf
.ignore_vmlinux_buildid
) {
708 u8 build_id
[BUILD_ID_SIZE
];
710 if (elf_read_build_id(elf
, build_id
, BUILD_ID_SIZE
) < 0) {
711 dso
->load_errno
= DSO_LOAD_ERRNO__CANNOT_READ_BUILDID
;
715 if (!dso__build_id_equal(dso
, build_id
)) {
716 pr_debug("%s: build id mismatch for %s.\n", __func__
, name
);
717 dso
->load_errno
= DSO_LOAD_ERRNO__MISMATCHING_BUILDID
;
722 ss
->is_64_bit
= (gelf_getclass(elf
) == ELFCLASS64
);
724 ss
->symtab
= elf_section_by_name(elf
, &ehdr
, &ss
->symshdr
, ".symtab",
726 if (ss
->symshdr
.sh_type
!= SHT_SYMTAB
)
730 ss
->dynsym
= elf_section_by_name(elf
, &ehdr
, &ss
->dynshdr
, ".dynsym",
732 if (ss
->dynshdr
.sh_type
!= SHT_DYNSYM
)
736 ss
->opdsec
= elf_section_by_name(elf
, &ehdr
, &ss
->opdshdr
, ".opd",
738 if (ss
->opdshdr
.sh_type
!= SHT_PROGBITS
)
741 if (dso
->kernel
== DSO_TYPE_USER
)
742 ss
->adjust_symbols
= true;
744 ss
->adjust_symbols
= elf__needs_adjust_symbols(ehdr
);
746 ss
->name
= strdup(name
);
748 dso
->load_errno
= errno
;
767 * ref_reloc_sym_not_found - has kernel relocation symbol been found.
768 * @kmap: kernel maps and relocation reference symbol
770 * This function returns %true if we are dealing with the kernel maps and the
771 * relocation reference symbol has not yet been found. Otherwise %false is
774 static bool ref_reloc_sym_not_found(struct kmap
*kmap
)
776 return kmap
&& kmap
->ref_reloc_sym
&& kmap
->ref_reloc_sym
->name
&&
777 !kmap
->ref_reloc_sym
->unrelocated_addr
;
781 * ref_reloc - kernel relocation offset.
782 * @kmap: kernel maps and relocation reference symbol
784 * This function returns the offset of kernel addresses as determined by using
785 * the relocation reference symbol i.e. if the kernel has not been relocated
786 * then the return value is zero.
788 static u64
ref_reloc(struct kmap
*kmap
)
790 if (kmap
&& kmap
->ref_reloc_sym
&&
791 kmap
->ref_reloc_sym
->unrelocated_addr
)
792 return kmap
->ref_reloc_sym
->addr
-
793 kmap
->ref_reloc_sym
->unrelocated_addr
;
797 void __weak
arch__sym_update(struct symbol
*s __maybe_unused
,
798 GElf_Sym
*sym __maybe_unused
) { }
800 int dso__load_sym(struct dso
*dso
, struct map
*map
, struct symsrc
*syms_ss
,
801 struct symsrc
*runtime_ss
, int kmodule
)
803 struct kmap
*kmap
= dso
->kernel
? map__kmap(map
) : NULL
;
804 struct map_groups
*kmaps
= kmap
? map__kmaps(map
) : NULL
;
805 struct map
*curr_map
= map
;
806 struct dso
*curr_dso
= dso
;
807 Elf_Data
*symstrs
, *secstrs
;
814 Elf_Data
*syms
, *opddata
= NULL
;
816 Elf_Scn
*sec
, *sec_strndx
;
819 bool remap_kernel
= false, adjust_kernel_syms
= false;
824 dso
->symtab_type
= syms_ss
->type
;
825 dso
->is_64_bit
= syms_ss
->is_64_bit
;
826 dso
->rel
= syms_ss
->ehdr
.e_type
== ET_REL
;
829 * Modules may already have symbols from kallsyms, but those symbols
830 * have the wrong values for the dso maps, so remove them.
832 if (kmodule
&& syms_ss
->symtab
)
833 symbols__delete(&dso
->symbols
);
835 if (!syms_ss
->symtab
) {
837 * If the vmlinux is stripped, fail so we will fall back
838 * to using kallsyms. The vmlinux runtime symbols aren't
844 syms_ss
->symtab
= syms_ss
->dynsym
;
845 syms_ss
->symshdr
= syms_ss
->dynshdr
;
849 ehdr
= syms_ss
->ehdr
;
850 sec
= syms_ss
->symtab
;
851 shdr
= syms_ss
->symshdr
;
853 if (elf_section_by_name(runtime_ss
->elf
, &runtime_ss
->ehdr
, &tshdr
,
855 dso
->text_offset
= tshdr
.sh_addr
- tshdr
.sh_offset
;
857 if (runtime_ss
->opdsec
)
858 opddata
= elf_rawdata(runtime_ss
->opdsec
, NULL
);
860 syms
= elf_getdata(sec
, NULL
);
864 sec
= elf_getscn(elf
, shdr
.sh_link
);
868 symstrs
= elf_getdata(sec
, NULL
);
872 sec_strndx
= elf_getscn(runtime_ss
->elf
, runtime_ss
->ehdr
.e_shstrndx
);
873 if (sec_strndx
== NULL
)
876 secstrs
= elf_getdata(sec_strndx
, NULL
);
880 nr_syms
= shdr
.sh_size
/ shdr
.sh_entsize
;
882 memset(&sym
, 0, sizeof(sym
));
885 * The kernel relocation symbol is needed in advance in order to adjust
886 * kernel maps correctly.
888 if (ref_reloc_sym_not_found(kmap
)) {
889 elf_symtab__for_each_symbol(syms
, nr_syms
, idx
, sym
) {
890 const char *elf_name
= elf_sym__name(&sym
, symstrs
);
892 if (strcmp(elf_name
, kmap
->ref_reloc_sym
->name
))
894 kmap
->ref_reloc_sym
->unrelocated_addr
= sym
.st_value
;
895 map
->reloc
= kmap
->ref_reloc_sym
->addr
-
896 kmap
->ref_reloc_sym
->unrelocated_addr
;
902 * Handle any relocation of vdso necessary because older kernels
903 * attempted to prelink vdso to its virtual address.
905 if (dso__is_vdso(dso
))
906 map
->reloc
= map
->start
- dso
->text_offset
;
908 dso
->adjust_symbols
= runtime_ss
->adjust_symbols
|| ref_reloc(kmap
);
910 * Initial kernel and module mappings do not map to the dso.
913 if (dso
->kernel
|| kmodule
) {
915 adjust_kernel_syms
= dso
->adjust_symbols
;
917 elf_symtab__for_each_symbol(syms
, nr_syms
, idx
, sym
) {
919 const char *elf_name
= elf_sym__name(&sym
, symstrs
);
920 char *demangled
= NULL
;
921 int is_label
= elf_sym__is_label(&sym
);
922 const char *section_name
;
923 bool used_opd
= false;
925 if (!is_label
&& !elf_sym__filter(&sym
))
928 /* Reject ARM ELF "mapping symbols": these aren't unique and
929 * don't identify functions, so will confuse the profile
931 if (ehdr
.e_machine
== EM_ARM
|| ehdr
.e_machine
== EM_AARCH64
) {
932 if (elf_name
[0] == '$' && strchr("adtx", elf_name
[1])
933 && (elf_name
[2] == '\0' || elf_name
[2] == '.'))
937 if (runtime_ss
->opdsec
&& sym
.st_shndx
== runtime_ss
->opdidx
) {
938 u32 offset
= sym
.st_value
- syms_ss
->opdshdr
.sh_addr
;
939 u64
*opd
= opddata
->d_buf
+ offset
;
940 sym
.st_value
= DSO__SWAP(dso
, u64
, *opd
);
941 sym
.st_shndx
= elf_addr_to_index(runtime_ss
->elf
,
946 * When loading symbols in a data mapping, ABS symbols (which
947 * has a value of SHN_ABS in its st_shndx) failed at
948 * elf_getscn(). And it marks the loading as a failure so
949 * already loaded symbols cannot be fixed up.
951 * I'm not sure what should be done. Just ignore them for now.
954 if (sym
.st_shndx
== SHN_ABS
)
957 sec
= elf_getscn(runtime_ss
->elf
, sym
.st_shndx
);
961 gelf_getshdr(sec
, &shdr
);
963 if (is_label
&& !elf_sec__filter(&shdr
, secstrs
))
966 section_name
= elf_sec__name(&shdr
, secstrs
);
968 /* On ARM, symbols for thumb functions have 1 added to
969 * the symbol address as a flag - remove it */
970 if ((ehdr
.e_machine
== EM_ARM
) &&
971 (GELF_ST_TYPE(sym
.st_info
) == STT_FUNC
) &&
975 if (dso
->kernel
|| kmodule
) {
976 char dso_name
[PATH_MAX
];
978 /* Adjust symbol to map to file offset */
979 if (adjust_kernel_syms
)
980 sym
.st_value
-= shdr
.sh_addr
- shdr
.sh_offset
;
982 if (strcmp(section_name
,
983 (curr_dso
->short_name
+
984 dso
->short_name_len
)) == 0)
987 if (strcmp(section_name
, ".text") == 0) {
989 * The initial kernel mapping is based on
990 * kallsyms and identity maps. Overwrite it to
991 * map to the kernel dso.
993 if (remap_kernel
&& dso
->kernel
) {
994 remap_kernel
= false;
995 map
->start
= shdr
.sh_addr
+
997 map
->end
= map
->start
+ shdr
.sh_size
;
998 map
->pgoff
= shdr
.sh_offset
;
999 map
->map_ip
= map__map_ip
;
1000 map
->unmap_ip
= map__unmap_ip
;
1001 /* Ensure maps are correctly ordered */
1004 map_groups__remove(kmaps
, map
);
1005 map_groups__insert(kmaps
, map
);
1011 * The initial module mapping is based on
1012 * /proc/modules mapped to offset zero.
1013 * Overwrite it to map to the module dso.
1015 if (remap_kernel
&& kmodule
) {
1016 remap_kernel
= false;
1017 map
->pgoff
= shdr
.sh_offset
;
1028 snprintf(dso_name
, sizeof(dso_name
),
1029 "%s%s", dso
->short_name
, section_name
);
1031 curr_map
= map_groups__find_by_name(kmaps
, dso_name
);
1032 if (curr_map
== NULL
) {
1033 u64 start
= sym
.st_value
;
1036 start
+= map
->start
+ shdr
.sh_offset
;
1038 curr_dso
= dso__new(dso_name
);
1039 if (curr_dso
== NULL
)
1041 curr_dso
->kernel
= dso
->kernel
;
1042 curr_dso
->long_name
= dso
->long_name
;
1043 curr_dso
->long_name_len
= dso
->long_name_len
;
1044 curr_map
= map__new2(start
, curr_dso
);
1046 if (curr_map
== NULL
) {
1049 if (adjust_kernel_syms
) {
1050 curr_map
->start
= shdr
.sh_addr
+
1052 curr_map
->end
= curr_map
->start
+
1054 curr_map
->pgoff
= shdr
.sh_offset
;
1056 curr_map
->map_ip
= identity__map_ip
;
1057 curr_map
->unmap_ip
= identity__map_ip
;
1059 curr_dso
->symtab_type
= dso
->symtab_type
;
1060 map_groups__insert(kmaps
, curr_map
);
1062 * Add it before we drop the referece to curr_map,
1063 * i.e. while we still are sure to have a reference
1064 * to this DSO via curr_map->dso.
1066 dsos__add(&map
->groups
->machine
->dsos
, curr_dso
);
1067 /* kmaps already got it */
1069 dso__set_loaded(curr_dso
);
1071 curr_dso
= curr_map
->dso
;
1076 if ((used_opd
&& runtime_ss
->adjust_symbols
)
1077 || (!used_opd
&& syms_ss
->adjust_symbols
)) {
1078 pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64
" "
1079 "sh_addr: %#" PRIx64
" sh_offset: %#" PRIx64
"\n", __func__
,
1080 (u64
)sym
.st_value
, (u64
)shdr
.sh_addr
,
1081 (u64
)shdr
.sh_offset
);
1082 sym
.st_value
-= shdr
.sh_addr
- shdr
.sh_offset
;
1085 demangled
= demangle_sym(dso
, kmodule
, elf_name
);
1086 if (demangled
!= NULL
)
1087 elf_name
= demangled
;
1089 f
= symbol__new(sym
.st_value
, sym
.st_size
,
1090 GELF_ST_BIND(sym
.st_info
),
1091 GELF_ST_TYPE(sym
.st_info
), elf_name
);
1096 arch__sym_update(f
, &sym
);
1098 __symbols__insert(&curr_dso
->symbols
, f
, dso
->kernel
);
1103 * For misannotated, zeroed, ASM function sizes.
1106 symbols__fixup_end(&dso
->symbols
);
1107 symbols__fixup_duplicate(&dso
->symbols
);
1110 * We need to fixup this here too because we create new
1111 * maps here, for things like vsyscall sections.
1113 map_groups__fixup_end(kmaps
);
1121 static int elf_read_maps(Elf
*elf
, bool exe
, mapfn_t mapfn
, void *data
)
1128 if (elf_getphdrnum(elf
, &phdrnum
))
1131 for (i
= 0; i
< phdrnum
; i
++) {
1132 if (gelf_getphdr(elf
, i
, &phdr
) == NULL
)
1134 if (phdr
.p_type
!= PT_LOAD
)
1137 if (!(phdr
.p_flags
& PF_X
))
1140 if (!(phdr
.p_flags
& PF_R
))
1143 sz
= min(phdr
.p_memsz
, phdr
.p_filesz
);
1146 err
= mapfn(phdr
.p_vaddr
, sz
, phdr
.p_offset
, data
);
1153 int file__read_maps(int fd
, bool exe
, mapfn_t mapfn
, void *data
,
1159 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
1164 *is_64_bit
= (gelf_getclass(elf
) == ELFCLASS64
);
1166 err
= elf_read_maps(elf
, exe
, mapfn
, data
);
1172 enum dso_type
dso__type_fd(int fd
)
1174 enum dso_type dso_type
= DSO__TYPE_UNKNOWN
;
1179 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
1184 if (ek
!= ELF_K_ELF
)
1187 if (gelf_getclass(elf
) == ELFCLASS64
) {
1188 dso_type
= DSO__TYPE_64BIT
;
1192 if (gelf_getehdr(elf
, &ehdr
) == NULL
)
1195 if (ehdr
.e_machine
== EM_X86_64
)
1196 dso_type
= DSO__TYPE_X32BIT
;
1198 dso_type
= DSO__TYPE_32BIT
;
1205 static int copy_bytes(int from
, off_t from_offs
, int to
, off_t to_offs
, u64 len
)
1210 char *buf
= malloc(page_size
);
1215 if (lseek(to
, to_offs
, SEEK_SET
) != to_offs
)
1218 if (lseek(from
, from_offs
, SEEK_SET
) != from_offs
)
1225 /* Use read because mmap won't work on proc files */
1226 r
= read(from
, buf
, n
);
1232 r
= write(to
, buf
, n
);
1253 static int kcore__open(struct kcore
*kcore
, const char *filename
)
1257 kcore
->fd
= open(filename
, O_RDONLY
);
1258 if (kcore
->fd
== -1)
1261 kcore
->elf
= elf_begin(kcore
->fd
, ELF_C_READ
, NULL
);
1265 kcore
->elfclass
= gelf_getclass(kcore
->elf
);
1266 if (kcore
->elfclass
== ELFCLASSNONE
)
1269 ehdr
= gelf_getehdr(kcore
->elf
, &kcore
->ehdr
);
1276 elf_end(kcore
->elf
);
1282 static int kcore__init(struct kcore
*kcore
, char *filename
, int elfclass
,
1285 kcore
->elfclass
= elfclass
;
1288 kcore
->fd
= mkstemp(filename
);
1290 kcore
->fd
= open(filename
, O_WRONLY
| O_CREAT
| O_EXCL
, 0400);
1291 if (kcore
->fd
== -1)
1294 kcore
->elf
= elf_begin(kcore
->fd
, ELF_C_WRITE
, NULL
);
1298 if (!gelf_newehdr(kcore
->elf
, elfclass
))
1301 memset(&kcore
->ehdr
, 0, sizeof(GElf_Ehdr
));
1306 elf_end(kcore
->elf
);
1313 static void kcore__close(struct kcore
*kcore
)
1315 elf_end(kcore
->elf
);
1319 static int kcore__copy_hdr(struct kcore
*from
, struct kcore
*to
, size_t count
)
1321 GElf_Ehdr
*ehdr
= &to
->ehdr
;
1322 GElf_Ehdr
*kehdr
= &from
->ehdr
;
1324 memcpy(ehdr
->e_ident
, kehdr
->e_ident
, EI_NIDENT
);
1325 ehdr
->e_type
= kehdr
->e_type
;
1326 ehdr
->e_machine
= kehdr
->e_machine
;
1327 ehdr
->e_version
= kehdr
->e_version
;
1330 ehdr
->e_flags
= kehdr
->e_flags
;
1331 ehdr
->e_phnum
= count
;
1332 ehdr
->e_shentsize
= 0;
1334 ehdr
->e_shstrndx
= 0;
1336 if (from
->elfclass
== ELFCLASS32
) {
1337 ehdr
->e_phoff
= sizeof(Elf32_Ehdr
);
1338 ehdr
->e_ehsize
= sizeof(Elf32_Ehdr
);
1339 ehdr
->e_phentsize
= sizeof(Elf32_Phdr
);
1341 ehdr
->e_phoff
= sizeof(Elf64_Ehdr
);
1342 ehdr
->e_ehsize
= sizeof(Elf64_Ehdr
);
1343 ehdr
->e_phentsize
= sizeof(Elf64_Phdr
);
1346 if (!gelf_update_ehdr(to
->elf
, ehdr
))
1349 if (!gelf_newphdr(to
->elf
, count
))
1355 static int kcore__add_phdr(struct kcore
*kcore
, int idx
, off_t offset
,
1360 .p_flags
= PF_R
| PF_W
| PF_X
,
1366 .p_align
= page_size
,
1369 if (!gelf_update_phdr(kcore
->elf
, idx
, &phdr
))
1375 static off_t
kcore__write(struct kcore
*kcore
)
1377 return elf_update(kcore
->elf
, ELF_C_WRITE
);
1386 struct kcore_copy_info
{
1392 u64 last_module_symbol
;
1393 struct phdr_data kernel_map
;
1394 struct phdr_data modules_map
;
1397 static int kcore_copy__process_kallsyms(void *arg
, const char *name
, char type
,
1400 struct kcore_copy_info
*kci
= arg
;
1402 if (!kallsyms__is_function(type
))
1405 if (strchr(name
, '[')) {
1406 if (start
> kci
->last_module_symbol
)
1407 kci
->last_module_symbol
= start
;
1411 if (!kci
->first_symbol
|| start
< kci
->first_symbol
)
1412 kci
->first_symbol
= start
;
1414 if (!kci
->last_symbol
|| start
> kci
->last_symbol
)
1415 kci
->last_symbol
= start
;
1417 if (!strcmp(name
, "_stext")) {
1422 if (!strcmp(name
, "_etext")) {
1430 static int kcore_copy__parse_kallsyms(struct kcore_copy_info
*kci
,
1433 char kallsyms_filename
[PATH_MAX
];
1435 scnprintf(kallsyms_filename
, PATH_MAX
, "%s/kallsyms", dir
);
1437 if (symbol__restricted_filename(kallsyms_filename
, "/proc/kallsyms"))
1440 if (kallsyms__parse(kallsyms_filename
, kci
,
1441 kcore_copy__process_kallsyms
) < 0)
1447 static int kcore_copy__process_modules(void *arg
,
1448 const char *name __maybe_unused
,
1449 u64 start
, u64 size __maybe_unused
)
1451 struct kcore_copy_info
*kci
= arg
;
1453 if (!kci
->first_module
|| start
< kci
->first_module
)
1454 kci
->first_module
= start
;
1459 static int kcore_copy__parse_modules(struct kcore_copy_info
*kci
,
1462 char modules_filename
[PATH_MAX
];
1464 scnprintf(modules_filename
, PATH_MAX
, "%s/modules", dir
);
1466 if (symbol__restricted_filename(modules_filename
, "/proc/modules"))
1469 if (modules__parse(modules_filename
, kci
,
1470 kcore_copy__process_modules
) < 0)
1476 static void kcore_copy__map(struct phdr_data
*p
, u64 start
, u64 end
, u64 pgoff
,
1479 if (p
->addr
|| s
< start
|| s
>= end
)
1483 p
->offset
= (s
- start
) + pgoff
;
1484 p
->len
= e
< end
? e
- s
: end
- s
;
1487 static int kcore_copy__read_map(u64 start
, u64 len
, u64 pgoff
, void *data
)
1489 struct kcore_copy_info
*kci
= data
;
1490 u64 end
= start
+ len
;
1492 kcore_copy__map(&kci
->kernel_map
, start
, end
, pgoff
, kci
->stext
,
1495 kcore_copy__map(&kci
->modules_map
, start
, end
, pgoff
, kci
->first_module
,
1496 kci
->last_module_symbol
);
1501 static int kcore_copy__read_maps(struct kcore_copy_info
*kci
, Elf
*elf
)
1503 if (elf_read_maps(elf
, true, kcore_copy__read_map
, kci
) < 0)
1509 static int kcore_copy__calc_maps(struct kcore_copy_info
*kci
, const char *dir
,
1512 if (kcore_copy__parse_kallsyms(kci
, dir
))
1515 if (kcore_copy__parse_modules(kci
, dir
))
1519 kci
->stext
= round_down(kci
->stext
, page_size
);
1521 kci
->stext
= round_down(kci
->first_symbol
, page_size
);
1524 kci
->etext
= round_up(kci
->etext
, page_size
);
1525 } else if (kci
->last_symbol
) {
1526 kci
->etext
= round_up(kci
->last_symbol
, page_size
);
1527 kci
->etext
+= page_size
;
1530 kci
->first_module
= round_down(kci
->first_module
, page_size
);
1532 if (kci
->last_module_symbol
) {
1533 kci
->last_module_symbol
= round_up(kci
->last_module_symbol
,
1535 kci
->last_module_symbol
+= page_size
;
1538 if (!kci
->stext
|| !kci
->etext
)
1541 if (kci
->first_module
&& !kci
->last_module_symbol
)
1544 return kcore_copy__read_maps(kci
, elf
);
1547 static int kcore_copy__copy_file(const char *from_dir
, const char *to_dir
,
1550 char from_filename
[PATH_MAX
];
1551 char to_filename
[PATH_MAX
];
1553 scnprintf(from_filename
, PATH_MAX
, "%s/%s", from_dir
, name
);
1554 scnprintf(to_filename
, PATH_MAX
, "%s/%s", to_dir
, name
);
1556 return copyfile_mode(from_filename
, to_filename
, 0400);
1559 static int kcore_copy__unlink(const char *dir
, const char *name
)
1561 char filename
[PATH_MAX
];
1563 scnprintf(filename
, PATH_MAX
, "%s/%s", dir
, name
);
1565 return unlink(filename
);
1568 static int kcore_copy__compare_fds(int from
, int to
)
1576 buf_from
= malloc(page_size
);
1577 buf_to
= malloc(page_size
);
1578 if (!buf_from
|| !buf_to
)
1582 /* Use read because mmap won't work on proc files */
1583 ret
= read(from
, buf_from
, page_size
);
1592 if (readn(to
, buf_to
, len
) != (int)len
)
1595 if (memcmp(buf_from
, buf_to
, len
))
1606 static int kcore_copy__compare_files(const char *from_filename
,
1607 const char *to_filename
)
1609 int from
, to
, err
= -1;
1611 from
= open(from_filename
, O_RDONLY
);
1615 to
= open(to_filename
, O_RDONLY
);
1617 goto out_close_from
;
1619 err
= kcore_copy__compare_fds(from
, to
);
1627 static int kcore_copy__compare_file(const char *from_dir
, const char *to_dir
,
1630 char from_filename
[PATH_MAX
];
1631 char to_filename
[PATH_MAX
];
1633 scnprintf(from_filename
, PATH_MAX
, "%s/%s", from_dir
, name
);
1634 scnprintf(to_filename
, PATH_MAX
, "%s/%s", to_dir
, name
);
1636 return kcore_copy__compare_files(from_filename
, to_filename
);
1640 * kcore_copy - copy kallsyms, modules and kcore from one directory to another.
1641 * @from_dir: from directory
1642 * @to_dir: to directory
1644 * This function copies kallsyms, modules and kcore files from one directory to
1645 * another. kallsyms and modules are copied entirely. Only code segments are
1646 * copied from kcore. It is assumed that two segments suffice: one for the
1647 * kernel proper and one for all the modules. The code segments are determined
1648 * from kallsyms and modules files. The kernel map starts at _stext or the
1649 * lowest function symbol, and ends at _etext or the highest function symbol.
1650 * The module map starts at the lowest module address and ends at the highest
1651 * module symbol. Start addresses are rounded down to the nearest page. End
1652 * addresses are rounded up to the nearest page. An extra page is added to the
1653 * highest kernel symbol and highest module symbol to, hopefully, encompass that
1654 * symbol too. Because it contains only code sections, the resulting kcore is
1655 * unusual. One significant peculiarity is that the mapping (start -> pgoff)
1656 * is not the same for the kernel map and the modules map. That happens because
1657 * the data is copied adjacently whereas the original kcore has gaps. Finally,
1658 * kallsyms and modules files are compared with their copies to check that
1659 * modules have not been loaded or unloaded while the copies were taking place.
1661 * Return: %0 on success, %-1 on failure.
1663 int kcore_copy(const char *from_dir
, const char *to_dir
)
1666 struct kcore extract
;
1668 int idx
= 0, err
= -1;
1669 off_t offset
= page_size
, sz
, modules_offset
= 0;
1670 struct kcore_copy_info kci
= { .stext
= 0, };
1671 char kcore_filename
[PATH_MAX
];
1672 char extract_filename
[PATH_MAX
];
1674 if (kcore_copy__copy_file(from_dir
, to_dir
, "kallsyms"))
1677 if (kcore_copy__copy_file(from_dir
, to_dir
, "modules"))
1678 goto out_unlink_kallsyms
;
1680 scnprintf(kcore_filename
, PATH_MAX
, "%s/kcore", from_dir
);
1681 scnprintf(extract_filename
, PATH_MAX
, "%s/kcore", to_dir
);
1683 if (kcore__open(&kcore
, kcore_filename
))
1684 goto out_unlink_modules
;
1686 if (kcore_copy__calc_maps(&kci
, from_dir
, kcore
.elf
))
1687 goto out_kcore_close
;
1689 if (kcore__init(&extract
, extract_filename
, kcore
.elfclass
, false))
1690 goto out_kcore_close
;
1692 if (!kci
.modules_map
.addr
)
1695 if (kcore__copy_hdr(&kcore
, &extract
, count
))
1696 goto out_extract_close
;
1698 if (kcore__add_phdr(&extract
, idx
++, offset
, kci
.kernel_map
.addr
,
1699 kci
.kernel_map
.len
))
1700 goto out_extract_close
;
1702 if (kci
.modules_map
.addr
) {
1703 modules_offset
= offset
+ kci
.kernel_map
.len
;
1704 if (kcore__add_phdr(&extract
, idx
, modules_offset
,
1705 kci
.modules_map
.addr
, kci
.modules_map
.len
))
1706 goto out_extract_close
;
1709 sz
= kcore__write(&extract
);
1710 if (sz
< 0 || sz
> offset
)
1711 goto out_extract_close
;
1713 if (copy_bytes(kcore
.fd
, kci
.kernel_map
.offset
, extract
.fd
, offset
,
1714 kci
.kernel_map
.len
))
1715 goto out_extract_close
;
1717 if (modules_offset
&& copy_bytes(kcore
.fd
, kci
.modules_map
.offset
,
1718 extract
.fd
, modules_offset
,
1719 kci
.modules_map
.len
))
1720 goto out_extract_close
;
1722 if (kcore_copy__compare_file(from_dir
, to_dir
, "modules"))
1723 goto out_extract_close
;
1725 if (kcore_copy__compare_file(from_dir
, to_dir
, "kallsyms"))
1726 goto out_extract_close
;
1731 kcore__close(&extract
);
1733 unlink(extract_filename
);
1735 kcore__close(&kcore
);
1738 kcore_copy__unlink(to_dir
, "modules");
1739 out_unlink_kallsyms
:
1741 kcore_copy__unlink(to_dir
, "kallsyms");
1746 int kcore_extract__create(struct kcore_extract
*kce
)
1749 struct kcore extract
;
1751 int idx
= 0, err
= -1;
1752 off_t offset
= page_size
, sz
;
1754 if (kcore__open(&kcore
, kce
->kcore_filename
))
1757 strcpy(kce
->extract_filename
, PERF_KCORE_EXTRACT
);
1758 if (kcore__init(&extract
, kce
->extract_filename
, kcore
.elfclass
, true))
1759 goto out_kcore_close
;
1761 if (kcore__copy_hdr(&kcore
, &extract
, count
))
1762 goto out_extract_close
;
1764 if (kcore__add_phdr(&extract
, idx
, offset
, kce
->addr
, kce
->len
))
1765 goto out_extract_close
;
1767 sz
= kcore__write(&extract
);
1768 if (sz
< 0 || sz
> offset
)
1769 goto out_extract_close
;
1771 if (copy_bytes(kcore
.fd
, kce
->offs
, extract
.fd
, offset
, kce
->len
))
1772 goto out_extract_close
;
1777 kcore__close(&extract
);
1779 unlink(kce
->extract_filename
);
1781 kcore__close(&kcore
);
1786 void kcore_extract__delete(struct kcore_extract
*kce
)
1788 unlink(kce
->extract_filename
);
1791 #ifdef HAVE_GELF_GETNOTE_SUPPORT
1793 * populate_sdt_note : Parse raw data and identify SDT note
1794 * @elf: elf of the opened file
1795 * @data: raw data of a section with description offset applied
1796 * @len: note description size
1797 * @type: type of the note
1798 * @sdt_notes: List to add the SDT note
1800 * Responsible for parsing the @data in section .note.stapsdt in @elf and
1801 * if its an SDT note, it appends to @sdt_notes list.
1803 static int populate_sdt_note(Elf
**elf
, const char *data
, size_t len
,
1804 struct list_head
*sdt_notes
)
1806 const char *provider
, *name
, *args
;
1807 struct sdt_note
*tmp
= NULL
;
1809 GElf_Addr base_off
= 0;
1814 Elf64_Addr a64
[NR_ADDR
];
1815 Elf32_Addr a32
[NR_ADDR
];
1819 .d_buf
= &buf
, .d_type
= ELF_T_ADDR
, .d_version
= EV_CURRENT
,
1820 .d_size
= gelf_fsize((*elf
), ELF_T_ADDR
, NR_ADDR
, EV_CURRENT
),
1821 .d_off
= 0, .d_align
= 0
1824 .d_buf
= (void *) data
, .d_type
= ELF_T_ADDR
,
1825 .d_version
= EV_CURRENT
, .d_size
= dst
.d_size
, .d_off
= 0,
1829 tmp
= (struct sdt_note
*)calloc(1, sizeof(struct sdt_note
));
1835 INIT_LIST_HEAD(&tmp
->note_list
);
1837 if (len
< dst
.d_size
+ 3)
1840 /* Translation from file representation to memory representation */
1841 if (gelf_xlatetom(*elf
, &dst
, &src
,
1842 elf_getident(*elf
, NULL
)[EI_DATA
]) == NULL
) {
1843 pr_err("gelf_xlatetom : %s\n", elf_errmsg(-1));
1847 /* Populate the fields of sdt_note */
1848 provider
= data
+ dst
.d_size
;
1850 name
= (const char *)memchr(provider
, '\0', data
+ len
- provider
);
1854 tmp
->provider
= strdup(provider
);
1855 if (!tmp
->provider
) {
1859 tmp
->name
= strdup(name
);
1865 args
= memchr(name
, '\0', data
+ len
- name
);
1868 * There is no argument if:
1869 * - We reached the end of the note;
1870 * - There is not enough room to hold a potential string;
1871 * - The argument string is empty or just contains ':'.
1873 if (args
== NULL
|| data
+ len
- args
< 2 ||
1874 args
[1] == ':' || args
[1] == '\0')
1877 tmp
->args
= strdup(++args
);
1884 if (gelf_getclass(*elf
) == ELFCLASS32
) {
1885 memcpy(&tmp
->addr
, &buf
, 3 * sizeof(Elf32_Addr
));
1888 memcpy(&tmp
->addr
, &buf
, 3 * sizeof(Elf64_Addr
));
1892 if (!gelf_getehdr(*elf
, &ehdr
)) {
1893 pr_debug("%s : cannot get elf header.\n", __func__
);
1898 /* Adjust the prelink effect :
1899 * Find out the .stapsdt.base section.
1900 * This scn will help us to handle prelinking (if present).
1901 * Compare the retrieved file offset of the base section with the
1902 * base address in the description of the SDT note. If its different,
1903 * then accordingly, adjust the note location.
1905 if (elf_section_by_name(*elf
, &ehdr
, &shdr
, SDT_BASE_SCN
, NULL
)) {
1906 base_off
= shdr
.sh_offset
;
1909 tmp
->addr
.a32
[0] = tmp
->addr
.a32
[0] + base_off
-
1912 tmp
->addr
.a64
[0] = tmp
->addr
.a64
[0] + base_off
-
1917 list_add_tail(&tmp
->note_list
, sdt_notes
);
1925 free(tmp
->provider
);
1933 * construct_sdt_notes_list : constructs a list of SDT notes
1934 * @elf : elf to look into
1935 * @sdt_notes : empty list_head
1937 * Scans the sections in 'elf' for the section
1938 * .note.stapsdt. It, then calls populate_sdt_note to find
1939 * out the SDT events and populates the 'sdt_notes'.
1941 static int construct_sdt_notes_list(Elf
*elf
, struct list_head
*sdt_notes
)
1944 Elf_Scn
*scn
= NULL
;
1947 size_t shstrndx
, next
;
1949 size_t name_off
, desc_off
, offset
;
1952 if (gelf_getehdr(elf
, &ehdr
) == NULL
) {
1956 if (elf_getshdrstrndx(elf
, &shstrndx
) != 0) {
1961 /* Look for the required section */
1962 scn
= elf_section_by_name(elf
, &ehdr
, &shdr
, SDT_NOTE_SCN
, NULL
);
1968 if ((shdr
.sh_type
!= SHT_NOTE
) || (shdr
.sh_flags
& SHF_ALLOC
)) {
1973 data
= elf_getdata(scn
, NULL
);
1975 /* Get the SDT notes */
1976 for (offset
= 0; (next
= gelf_getnote(data
, offset
, &nhdr
, &name_off
,
1977 &desc_off
)) > 0; offset
= next
) {
1978 if (nhdr
.n_namesz
== sizeof(SDT_NOTE_NAME
) &&
1979 !memcmp(data
->d_buf
+ name_off
, SDT_NOTE_NAME
,
1980 sizeof(SDT_NOTE_NAME
))) {
1981 /* Check the type of the note */
1982 if (nhdr
.n_type
!= SDT_NOTE_TYPE
)
1985 ret
= populate_sdt_note(&elf
, ((data
->d_buf
) + desc_off
),
1986 nhdr
.n_descsz
, sdt_notes
);
1991 if (list_empty(sdt_notes
))
1999 * get_sdt_note_list : Wrapper to construct a list of sdt notes
2000 * @head : empty list_head
2001 * @target : file to find SDT notes from
2003 * This opens the file, initializes
2004 * the ELF and then calls construct_sdt_notes_list.
2006 int get_sdt_note_list(struct list_head
*head
, const char *target
)
2011 fd
= open(target
, O_RDONLY
);
2015 elf
= elf_begin(fd
, PERF_ELF_C_READ_MMAP
, NULL
);
2020 ret
= construct_sdt_notes_list(elf
, head
);
2028 * cleanup_sdt_note_list : free the sdt notes' list
2029 * @sdt_notes: sdt notes' list
2031 * Free up the SDT notes in @sdt_notes.
2032 * Returns the number of SDT notes free'd.
2034 int cleanup_sdt_note_list(struct list_head
*sdt_notes
)
2036 struct sdt_note
*tmp
, *pos
;
2039 list_for_each_entry_safe(pos
, tmp
, sdt_notes
, note_list
) {
2040 list_del(&pos
->note_list
);
2042 free(pos
->provider
);
2050 * sdt_notes__get_count: Counts the number of sdt events
2051 * @start: list_head to sdt_notes list
2053 * Returns the number of SDT notes in a list
2055 int sdt_notes__get_count(struct list_head
*start
)
2057 struct sdt_note
*sdt_ptr
;
2060 list_for_each_entry(sdt_ptr
, start
, note_list
)
2066 void symbol__elf_init(void)
2068 elf_version(EV_CURRENT
);