| |
| #include <unistd.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| #include <stdlib.h> |
| #include <linux/kernel.h> |
| |
| #include "vdso.h" |
| #include "util.h" |
| #include "symbol.h" |
| #include "machine.h" |
| #include "thread.h" |
| #include "linux/string.h" |
| #include "debug.h" |
| |
| /* |
| * Include definition of find_vdso_map() also used in perf-read-vdso.c for |
| * building perf-read-vdso32 and perf-read-vdsox32. |
| */ |
| #include "find-vdso-map.c" |
| |
| #define VDSO__TEMP_FILE_NAME "/tmp/perf-vdso.so-XXXXXX" |
| |
| struct vdso_file { |
| bool found; |
| bool error; |
| char temp_file_name[sizeof(VDSO__TEMP_FILE_NAME)]; |
| const char *dso_name; |
| const char *read_prog; |
| }; |
| |
| struct vdso_info { |
| struct vdso_file vdso; |
| #if BITS_PER_LONG == 64 |
| struct vdso_file vdso32; |
| struct vdso_file vdsox32; |
| #endif |
| }; |
| |
| static struct vdso_info *vdso_info__new(void) |
| { |
| static const struct vdso_info vdso_info_init = { |
| .vdso = { |
| .temp_file_name = VDSO__TEMP_FILE_NAME, |
| .dso_name = DSO__NAME_VDSO, |
| }, |
| #if BITS_PER_LONG == 64 |
| .vdso32 = { |
| .temp_file_name = VDSO__TEMP_FILE_NAME, |
| .dso_name = DSO__NAME_VDSO32, |
| .read_prog = "perf-read-vdso32", |
| }, |
| .vdsox32 = { |
| .temp_file_name = VDSO__TEMP_FILE_NAME, |
| .dso_name = DSO__NAME_VDSOX32, |
| .read_prog = "perf-read-vdsox32", |
| }, |
| #endif |
| }; |
| |
| return memdup(&vdso_info_init, sizeof(vdso_info_init)); |
| } |
| |
| static char *get_file(struct vdso_file *vdso_file) |
| { |
| char *vdso = NULL; |
| char *buf = NULL; |
| void *start, *end; |
| size_t size; |
| int fd; |
| |
| if (vdso_file->found) |
| return vdso_file->temp_file_name; |
| |
| if (vdso_file->error || find_vdso_map(&start, &end)) |
| return NULL; |
| |
| size = end - start; |
| |
| buf = memdup(start, size); |
| if (!buf) |
| return NULL; |
| |
| fd = mkstemp(vdso_file->temp_file_name); |
| if (fd < 0) |
| goto out; |
| |
| if (size == (size_t) write(fd, buf, size)) |
| vdso = vdso_file->temp_file_name; |
| |
| close(fd); |
| |
| out: |
| free(buf); |
| |
| vdso_file->found = (vdso != NULL); |
| vdso_file->error = !vdso_file->found; |
| return vdso; |
| } |
| |
| void machine__exit_vdso(struct machine *machine) |
| { |
| struct vdso_info *vdso_info = machine->vdso_info; |
| |
| if (!vdso_info) |
| return; |
| |
| if (vdso_info->vdso.found) |
| unlink(vdso_info->vdso.temp_file_name); |
| #if BITS_PER_LONG == 64 |
| if (vdso_info->vdso32.found) |
| unlink(vdso_info->vdso32.temp_file_name); |
| if (vdso_info->vdsox32.found) |
| unlink(vdso_info->vdsox32.temp_file_name); |
| #endif |
| |
| zfree(&machine->vdso_info); |
| } |
| |
| static struct dso *machine__addnew_vdso(struct machine *machine, const char *short_name, |
| const char *long_name) |
| { |
| struct dso *dso; |
| |
| dso = dso__new(short_name); |
| if (dso != NULL) { |
| dsos__add(&machine->dsos, dso); |
| dso__set_long_name(dso, long_name, false); |
| } |
| |
| return dso; |
| } |
| |
| #if BITS_PER_LONG == 64 |
| |
| static enum dso_type machine__thread_dso_type(struct machine *machine, |
| struct thread *thread) |
| { |
| enum dso_type dso_type = DSO__TYPE_UNKNOWN; |
| struct map *map; |
| struct dso *dso; |
| |
| map = map_groups__first(thread->mg, MAP__FUNCTION); |
| for (; map ; map = map_groups__next(map)) { |
| dso = map->dso; |
| if (!dso || dso->long_name[0] != '/') |
| continue; |
| dso_type = dso__type(dso, machine); |
| if (dso_type != DSO__TYPE_UNKNOWN) |
| break; |
| } |
| |
| return dso_type; |
| } |
| |
| static int vdso__do_copy_compat(FILE *f, int fd) |
| { |
| char buf[4096]; |
| size_t count; |
| |
| while (1) { |
| count = fread(buf, 1, sizeof(buf), f); |
| if (ferror(f)) |
| return -errno; |
| if (feof(f)) |
| break; |
| if (count && writen(fd, buf, count) != (ssize_t)count) |
| return -errno; |
| } |
| |
| return 0; |
| } |
| |
| static int vdso__copy_compat(const char *prog, int fd) |
| { |
| FILE *f; |
| int err; |
| |
| f = popen(prog, "r"); |
| if (!f) |
| return -errno; |
| |
| err = vdso__do_copy_compat(f, fd); |
| |
| if (pclose(f) == -1) |
| return -errno; |
| |
| return err; |
| } |
| |
| static int vdso__create_compat_file(const char *prog, char *temp_name) |
| { |
| int fd, err; |
| |
| fd = mkstemp(temp_name); |
| if (fd < 0) |
| return -errno; |
| |
| err = vdso__copy_compat(prog, fd); |
| |
| if (close(fd) == -1) |
| return -errno; |
| |
| return err; |
| } |
| |
| static const char *vdso__get_compat_file(struct vdso_file *vdso_file) |
| { |
| int err; |
| |
| if (vdso_file->found) |
| return vdso_file->temp_file_name; |
| |
| if (vdso_file->error) |
| return NULL; |
| |
| err = vdso__create_compat_file(vdso_file->read_prog, |
| vdso_file->temp_file_name); |
| if (err) { |
| pr_err("%s failed, error %d\n", vdso_file->read_prog, err); |
| vdso_file->error = true; |
| return NULL; |
| } |
| |
| vdso_file->found = true; |
| |
| return vdso_file->temp_file_name; |
| } |
| |
| static struct dso *vdso__findnew_compat(struct machine *machine, |
| struct vdso_file *vdso_file) |
| { |
| const char *file_name; |
| struct dso *dso; |
| |
| dso = dsos__find(&machine->dsos, vdso_file->dso_name, true); |
| if (dso) |
| return dso; |
| |
| file_name = vdso__get_compat_file(vdso_file); |
| if (!file_name) |
| return NULL; |
| |
| return machine__addnew_vdso(machine, vdso_file->dso_name, file_name); |
| } |
| |
| static int machine__findnew_vdso_compat(struct machine *machine, |
| struct thread *thread, |
| struct vdso_info *vdso_info, |
| struct dso **dso) |
| { |
| enum dso_type dso_type; |
| |
| dso_type = machine__thread_dso_type(machine, thread); |
| |
| #ifndef HAVE_PERF_READ_VDSO32 |
| if (dso_type == DSO__TYPE_32BIT) |
| return 0; |
| #endif |
| #ifndef HAVE_PERF_READ_VDSOX32 |
| if (dso_type == DSO__TYPE_X32BIT) |
| return 0; |
| #endif |
| |
| switch (dso_type) { |
| case DSO__TYPE_32BIT: |
| *dso = vdso__findnew_compat(machine, &vdso_info->vdso32); |
| return 1; |
| case DSO__TYPE_X32BIT: |
| *dso = vdso__findnew_compat(machine, &vdso_info->vdsox32); |
| return 1; |
| case DSO__TYPE_UNKNOWN: |
| case DSO__TYPE_64BIT: |
| default: |
| return 0; |
| } |
| } |
| |
| #endif |
| |
| struct dso *machine__findnew_vdso(struct machine *machine, |
| struct thread *thread __maybe_unused) |
| { |
| struct vdso_info *vdso_info; |
| struct dso *dso; |
| |
| if (!machine->vdso_info) |
| machine->vdso_info = vdso_info__new(); |
| |
| vdso_info = machine->vdso_info; |
| if (!vdso_info) |
| return NULL; |
| |
| #if BITS_PER_LONG == 64 |
| if (machine__findnew_vdso_compat(machine, thread, vdso_info, &dso)) |
| return dso; |
| #endif |
| |
| dso = dsos__find(&machine->dsos, DSO__NAME_VDSO, true); |
| if (!dso) { |
| char *file; |
| |
| file = get_file(&vdso_info->vdso); |
| if (!file) |
| return NULL; |
| |
| dso = machine__addnew_vdso(machine, DSO__NAME_VDSO, file); |
| } |
| |
| return dso; |
| } |
| |
| bool dso__is_vdso(struct dso *dso) |
| { |
| return !strcmp(dso->short_name, DSO__NAME_VDSO) || |
| !strcmp(dso->short_name, DSO__NAME_VDSO32) || |
| !strcmp(dso->short_name, DSO__NAME_VDSOX32); |
| } |