swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: 7e57714cd0ad2d5bb90e50b5096a0e671dec1ef3 authored by Linus Torvalds on 27 February 2022, 22:36:33 UTC
Linux 5.17-rc6
Linux 5.17-rc6
Tip revision: 7e57714
dso.c
// SPDX-License-Identifier: GPL-2.0
#include <asm/bug.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/zalloc.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#ifdef HAVE_LIBBPF_SUPPORT
#include <bpf/libbpf.h>
#include "bpf-event.h"
#include "bpf-utils.h"
#endif
#include "compress.h"
#include "env.h"
#include "namespaces.h"
#include "path.h"
#include "map.h"
#include "symbol.h"
#include "srcline.h"
#include "dso.h"
#include "dsos.h"
#include "machine.h"
#include "auxtrace.h"
#include "util.h" /* O_CLOEXEC for older systems */
#include "debug.h"
#include "string2.h"
#include "vdso.h"
static const char * const debuglink_paths[] = {
"%.0s%s",
"%s/%s",
"%s/.debug/%s",
"/usr/lib/debug%s/%s"
};
char dso__symtab_origin(const struct dso *dso)
{
static const char origin[] = {
[DSO_BINARY_TYPE__KALLSYMS] = 'k',
[DSO_BINARY_TYPE__VMLINUX] = 'v',
[DSO_BINARY_TYPE__JAVA_JIT] = 'j',
[DSO_BINARY_TYPE__DEBUGLINK] = 'l',
[DSO_BINARY_TYPE__BUILD_ID_CACHE] = 'B',
[DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO] = 'D',
[DSO_BINARY_TYPE__FEDORA_DEBUGINFO] = 'f',
[DSO_BINARY_TYPE__UBUNTU_DEBUGINFO] = 'u',
[DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO] = 'x',
[DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO] = 'o',
[DSO_BINARY_TYPE__BUILDID_DEBUGINFO] = 'b',
[DSO_BINARY_TYPE__SYSTEM_PATH_DSO] = 'd',
[DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE] = 'K',
[DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP] = 'm',
[DSO_BINARY_TYPE__GUEST_KALLSYMS] = 'g',
[DSO_BINARY_TYPE__GUEST_KMODULE] = 'G',
[DSO_BINARY_TYPE__GUEST_KMODULE_COMP] = 'M',
[DSO_BINARY_TYPE__GUEST_VMLINUX] = 'V',
};
if (dso == NULL || dso->symtab_type == DSO_BINARY_TYPE__NOT_FOUND)
return '!';
return origin[dso->symtab_type];
}
int dso__read_binary_type_filename(const struct dso *dso,
enum dso_binary_type type,
char *root_dir, char *filename, size_t size)
{
char build_id_hex[SBUILD_ID_SIZE];
int ret = 0;
size_t len;
switch (type) {
case DSO_BINARY_TYPE__DEBUGLINK:
{
const char *last_slash;
char dso_dir[PATH_MAX];
char symfile[PATH_MAX];
unsigned int i;
len = __symbol__join_symfs(filename, size, dso->long_name);
last_slash = filename + len;
while (last_slash != filename && *last_slash != '/')
last_slash--;
strncpy(dso_dir, filename, last_slash - filename);
dso_dir[last_slash-filename] = '\0';
if (!is_regular_file(filename)) {
ret = -1;
break;
}
ret = filename__read_debuglink(filename, symfile, PATH_MAX);
if (ret)
break;
/* Check predefined locations where debug file might reside */
ret = -1;
for (i = 0; i < ARRAY_SIZE(debuglink_paths); i++) {
snprintf(filename, size,
debuglink_paths[i], dso_dir, symfile);
if (is_regular_file(filename)) {
ret = 0;
break;
}
}
break;
}
case DSO_BINARY_TYPE__BUILD_ID_CACHE:
if (dso__build_id_filename(dso, filename, size, false) == NULL)
ret = -1;
break;
case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
if (dso__build_id_filename(dso, filename, size, true) == NULL)
ret = -1;
break;
case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
snprintf(filename + len, size - len, "%s.debug", dso->long_name);
break;
case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
snprintf(filename + len, size - len, "%s", dso->long_name);
break;
case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
/*
* Ubuntu can mixup /usr/lib with /lib, putting debuginfo in
* /usr/lib/debug/lib when it is expected to be in
* /usr/lib/debug/usr/lib
*/
if (strlen(dso->long_name) < 9 ||
strncmp(dso->long_name, "/usr/lib/", 9)) {
ret = -1;
break;
}
len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
snprintf(filename + len, size - len, "%s", dso->long_name + 4);
break;
case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
{
const char *last_slash;
size_t dir_size;
last_slash = dso->long_name + dso->long_name_len;
while (last_slash != dso->long_name && *last_slash != '/')
last_slash--;
len = __symbol__join_symfs(filename, size, "");
dir_size = last_slash - dso->long_name + 2;
if (dir_size > (size - len)) {
ret = -1;
break;
}
len += scnprintf(filename + len, dir_size, "%s", dso->long_name);
len += scnprintf(filename + len , size - len, ".debug%s",
last_slash);
break;
}
case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
if (!dso->has_build_id) {
ret = -1;
break;
}
build_id__sprintf(&dso->bid, build_id_hex);
len = __symbol__join_symfs(filename, size, "/usr/lib/debug/.build-id/");
snprintf(filename + len, size - len, "%.2s/%s.debug",
build_id_hex, build_id_hex + 2);
break;
case DSO_BINARY_TYPE__VMLINUX:
case DSO_BINARY_TYPE__GUEST_VMLINUX:
case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
__symbol__join_symfs(filename, size, dso->long_name);
break;
case DSO_BINARY_TYPE__GUEST_KMODULE:
case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
path__join3(filename, size, symbol_conf.symfs,
root_dir, dso->long_name);
break;
case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
__symbol__join_symfs(filename, size, dso->long_name);
break;
case DSO_BINARY_TYPE__KCORE:
case DSO_BINARY_TYPE__GUEST_KCORE:
snprintf(filename, size, "%s", dso->long_name);
break;
default:
case DSO_BINARY_TYPE__KALLSYMS:
case DSO_BINARY_TYPE__GUEST_KALLSYMS:
case DSO_BINARY_TYPE__JAVA_JIT:
case DSO_BINARY_TYPE__BPF_PROG_INFO:
case DSO_BINARY_TYPE__BPF_IMAGE:
case DSO_BINARY_TYPE__OOL:
case DSO_BINARY_TYPE__NOT_FOUND:
ret = -1;
break;
}
return ret;
}
enum {
COMP_ID__NONE = 0,
};
static const struct {
const char *fmt;
int (*decompress)(const char *input, int output);
bool (*is_compressed)(const char *input);
} compressions[] = {
[COMP_ID__NONE] = { .fmt = NULL, },
#ifdef HAVE_ZLIB_SUPPORT
{ "gz", gzip_decompress_to_file, gzip_is_compressed },
#endif
#ifdef HAVE_LZMA_SUPPORT
{ "xz", lzma_decompress_to_file, lzma_is_compressed },
#endif
{ NULL, NULL, NULL },
};
static int is_supported_compression(const char *ext)
{
unsigned i;
for (i = 1; compressions[i].fmt; i++) {
if (!strcmp(ext, compressions[i].fmt))
return i;
}
return COMP_ID__NONE;
}
bool is_kernel_module(const char *pathname, int cpumode)
{
struct kmod_path m;
int mode = cpumode & PERF_RECORD_MISC_CPUMODE_MASK;
WARN_ONCE(mode != cpumode,
"Internal error: passing unmasked cpumode (%x) to is_kernel_module",
cpumode);
switch (mode) {
case PERF_RECORD_MISC_USER:
case PERF_RECORD_MISC_HYPERVISOR:
case PERF_RECORD_MISC_GUEST_USER:
return false;
/* Treat PERF_RECORD_MISC_CPUMODE_UNKNOWN as kernel */
default:
if (kmod_path__parse(&m, pathname)) {
pr_err("Failed to check whether %s is a kernel module or not. Assume it is.",
pathname);
return true;
}
}
return m.kmod;
}
bool dso__needs_decompress(struct dso *dso)
{
return dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
}
int filename__decompress(const char *name, char *pathname,
size_t len, int comp, int *err)
{
char tmpbuf[] = KMOD_DECOMP_NAME;
int fd = -1;
/*
* We have proper compression id for DSO and yet the file
* behind the 'name' can still be plain uncompressed object.
*
* The reason is behind the logic we open the DSO object files,
* when we try all possible 'debug' objects until we find the
* data. So even if the DSO is represented by 'krava.xz' module,
* we can end up here opening ~/.debug/....23432432/debug' file
* which is not compressed.
*
* To keep this transparent, we detect this and return the file
* descriptor to the uncompressed file.
*/
if (!compressions[comp].is_compressed(name))
return open(name, O_RDONLY);
fd = mkstemp(tmpbuf);
if (fd < 0) {
*err = errno;
return -1;
}
if (compressions[comp].decompress(name, fd)) {
*err = DSO_LOAD_ERRNO__DECOMPRESSION_FAILURE;
close(fd);
fd = -1;
}
if (!pathname || (fd < 0))
unlink(tmpbuf);
if (pathname && (fd >= 0))
strlcpy(pathname, tmpbuf, len);
return fd;
}
static int decompress_kmodule(struct dso *dso, const char *name,
char *pathname, size_t len)
{
if (!dso__needs_decompress(dso))
return -1;
if (dso->comp == COMP_ID__NONE)
return -1;
return filename__decompress(name, pathname, len, dso->comp,
&dso->load_errno);
}
int dso__decompress_kmodule_fd(struct dso *dso, const char *name)
{
return decompress_kmodule(dso, name, NULL, 0);
}
int dso__decompress_kmodule_path(struct dso *dso, const char *name,
char *pathname, size_t len)
{
int fd = decompress_kmodule(dso, name, pathname, len);
close(fd);
return fd >= 0 ? 0 : -1;
}
/*
* Parses kernel module specified in @path and updates
* @m argument like:
*
* @comp - true if @path contains supported compression suffix,
* false otherwise
* @kmod - true if @path contains '.ko' suffix in right position,
* false otherwise
* @name - if (@alloc_name && @kmod) is true, it contains strdup-ed base name
* of the kernel module without suffixes, otherwise strudup-ed
* base name of @path
* @ext - if (@alloc_ext && @comp) is true, it contains strdup-ed string
* the compression suffix
*
* Returns 0 if there's no strdup error, -ENOMEM otherwise.
*/
int __kmod_path__parse(struct kmod_path *m, const char *path,
bool alloc_name)
{
const char *name = strrchr(path, '/');
const char *ext = strrchr(path, '.');
bool is_simple_name = false;
memset(m, 0x0, sizeof(*m));
name = name ? name + 1 : path;
/*
* '.' is also a valid character for module name. For example:
* [aaa.bbb] is a valid module name. '[' should have higher
* priority than '.ko' suffix.
*
* The kernel names are from machine__mmap_name. Such
* name should belong to kernel itself, not kernel module.
*/
if (name[0] == '[') {
is_simple_name = true;
if ((strncmp(name, "[kernel.kallsyms]", 17) == 0) ||
(strncmp(name, "[guest.kernel.kallsyms", 22) == 0) ||
(strncmp(name, "[vdso]", 6) == 0) ||
(strncmp(name, "[vdso32]", 8) == 0) ||
(strncmp(name, "[vdsox32]", 9) == 0) ||
(strncmp(name, "[vsyscall]", 10) == 0)) {
m->kmod = false;
} else
m->kmod = true;
}
/* No extension, just return name. */
if ((ext == NULL) || is_simple_name) {
if (alloc_name) {
m->name = strdup(name);
return m->name ? 0 : -ENOMEM;
}
return 0;
}
m->comp = is_supported_compression(ext + 1);
if (m->comp > COMP_ID__NONE)
ext -= 3;
/* Check .ko extension only if there's enough name left. */
if (ext > name)
m->kmod = !strncmp(ext, ".ko", 3);
if (alloc_name) {
if (m->kmod) {
if (asprintf(&m->name, "[%.*s]", (int) (ext - name), name) == -1)
return -ENOMEM;
} else {
if (asprintf(&m->name, "%s", name) == -1)
return -ENOMEM;
}
strreplace(m->name, '-', '_');
}
return 0;
}
void dso__set_module_info(struct dso *dso, struct kmod_path *m,
struct machine *machine)
{
if (machine__is_host(machine))
dso->symtab_type = DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE;
else
dso->symtab_type = DSO_BINARY_TYPE__GUEST_KMODULE;
/* _KMODULE_COMP should be next to _KMODULE */
if (m->kmod && m->comp) {
dso->symtab_type++;
dso->comp = m->comp;
}
dso__set_short_name(dso, strdup(m->name), true);
}
/*
* Global list of open DSOs and the counter.
*/
static LIST_HEAD(dso__data_open);
static long dso__data_open_cnt;
static pthread_mutex_t dso__data_open_lock = PTHREAD_MUTEX_INITIALIZER;
static void dso__list_add(struct dso *dso)
{
list_add_tail(&dso->data.open_entry, &dso__data_open);
dso__data_open_cnt++;
}
static void dso__list_del(struct dso *dso)
{
list_del_init(&dso->data.open_entry);
WARN_ONCE(dso__data_open_cnt <= 0,
"DSO data fd counter out of bounds.");
dso__data_open_cnt--;
}
static void close_first_dso(void);
static int do_open(char *name)
{
int fd;
char sbuf[STRERR_BUFSIZE];
do {
fd = open(name, O_RDONLY|O_CLOEXEC);
if (fd >= 0)
return fd;
pr_debug("dso open failed: %s\n",
str_error_r(errno, sbuf, sizeof(sbuf)));
if (!dso__data_open_cnt || errno != EMFILE)
break;
close_first_dso();
} while (1);
return -1;
}
static int __open_dso(struct dso *dso, struct machine *machine)
{
int fd = -EINVAL;
char *root_dir = (char *)"";
char *name = malloc(PATH_MAX);
bool decomp = false;
if (!name)
return -ENOMEM;
if (machine)
root_dir = machine->root_dir;
if (dso__read_binary_type_filename(dso, dso->binary_type,
root_dir, name, PATH_MAX))
goto out;
if (!is_regular_file(name))
goto out;
if (dso__needs_decompress(dso)) {
char newpath[KMOD_DECOMP_LEN];
size_t len = sizeof(newpath);
if (dso__decompress_kmodule_path(dso, name, newpath, len) < 0) {
fd = -dso->load_errno;
goto out;
}
decomp = true;
strcpy(name, newpath);
}
fd = do_open(name);
if (decomp)
unlink(name);
out:
free(name);
return fd;
}
static void check_data_close(void);
/**
* dso_close - Open DSO data file
* @dso: dso object
*
* Open @dso's data file descriptor and updates
* list/count of open DSO objects.
*/
static int open_dso(struct dso *dso, struct machine *machine)
{
int fd;
struct nscookie nsc;
if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE)
nsinfo__mountns_enter(dso->nsinfo, &nsc);
fd = __open_dso(dso, machine);
if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE)
nsinfo__mountns_exit(&nsc);
if (fd >= 0) {
dso__list_add(dso);
/*
* Check if we crossed the allowed number
* of opened DSOs and close one if needed.
*/
check_data_close();
}
return fd;
}
static void close_data_fd(struct dso *dso)
{
if (dso->data.fd >= 0) {
close(dso->data.fd);
dso->data.fd = -1;
dso->data.file_size = 0;
dso__list_del(dso);
}
}
/**
* dso_close - Close DSO data file
* @dso: dso object
*
* Close @dso's data file descriptor and updates
* list/count of open DSO objects.
*/
static void close_dso(struct dso *dso)
{
close_data_fd(dso);
}
static void close_first_dso(void)
{
struct dso *dso;
dso = list_first_entry(&dso__data_open, struct dso, data.open_entry);
close_dso(dso);
}
static rlim_t get_fd_limit(void)
{
struct rlimit l;
rlim_t limit = 0;
/* Allow half of the current open fd limit. */
if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
if (l.rlim_cur == RLIM_INFINITY)
limit = l.rlim_cur;
else
limit = l.rlim_cur / 2;
} else {
pr_err("failed to get fd limit\n");
limit = 1;
}
return limit;
}
static rlim_t fd_limit;
/*
* Used only by tests/dso-data.c to reset the environment
* for tests. I dont expect we should change this during
* standard runtime.
*/
void reset_fd_limit(void)
{
fd_limit = 0;
}
static bool may_cache_fd(void)
{
if (!fd_limit)
fd_limit = get_fd_limit();
if (fd_limit == RLIM_INFINITY)
return true;
return fd_limit > (rlim_t) dso__data_open_cnt;
}
/*
* Check and close LRU dso if we crossed allowed limit
* for opened dso file descriptors. The limit is half
* of the RLIMIT_NOFILE files opened.
*/
static void check_data_close(void)
{
bool cache_fd = may_cache_fd();
if (!cache_fd)
close_first_dso();
}
/**
* dso__data_close - Close DSO data file
* @dso: dso object
*
* External interface to close @dso's data file descriptor.
*/
void dso__data_close(struct dso *dso)
{
pthread_mutex_lock(&dso__data_open_lock);
close_dso(dso);
pthread_mutex_unlock(&dso__data_open_lock);
}
static void try_to_open_dso(struct dso *dso, struct machine *machine)
{
enum dso_binary_type binary_type_data[] = {
DSO_BINARY_TYPE__BUILD_ID_CACHE,
DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
DSO_BINARY_TYPE__NOT_FOUND,
};
int i = 0;
if (dso->data.fd >= 0)
return;
if (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND) {
dso->data.fd = open_dso(dso, machine);
goto out;
}
do {
dso->binary_type = binary_type_data[i++];
dso->data.fd = open_dso(dso, machine);
if (dso->data.fd >= 0)
goto out;
} while (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND);
out:
if (dso->data.fd >= 0)
dso->data.status = DSO_DATA_STATUS_OK;
else
dso->data.status = DSO_DATA_STATUS_ERROR;
}
/**
* dso__data_get_fd - Get dso's data file descriptor
* @dso: dso object
* @machine: machine object
*
* External interface to find dso's file, open it and
* returns file descriptor. It should be paired with
* dso__data_put_fd() if it returns non-negative value.
*/
int dso__data_get_fd(struct dso *dso, struct machine *machine)
{
if (dso->data.status == DSO_DATA_STATUS_ERROR)
return -1;
if (pthread_mutex_lock(&dso__data_open_lock) < 0)
return -1;
try_to_open_dso(dso, machine);
if (dso->data.fd < 0)
pthread_mutex_unlock(&dso__data_open_lock);
return dso->data.fd;
}
void dso__data_put_fd(struct dso *dso __maybe_unused)
{
pthread_mutex_unlock(&dso__data_open_lock);
}
bool dso__data_status_seen(struct dso *dso, enum dso_data_status_seen by)
{
u32 flag = 1 << by;
if (dso->data.status_seen & flag)
return true;
dso->data.status_seen |= flag;
return false;
}
#ifdef HAVE_LIBBPF_SUPPORT
static ssize_t bpf_read(struct dso *dso, u64 offset, char *data)
{
struct bpf_prog_info_node *node;
ssize_t size = DSO__DATA_CACHE_SIZE;
u64 len;
u8 *buf;
node = perf_env__find_bpf_prog_info(dso->bpf_prog.env, dso->bpf_prog.id);
if (!node || !node->info_linear) {
dso->data.status = DSO_DATA_STATUS_ERROR;
return -1;
}
len = node->info_linear->info.jited_prog_len;
buf = (u8 *)(uintptr_t)node->info_linear->info.jited_prog_insns;
if (offset >= len)
return -1;
size = (ssize_t)min(len - offset, (u64)size);
memcpy(data, buf + offset, size);
return size;
}
static int bpf_size(struct dso *dso)
{
struct bpf_prog_info_node *node;
node = perf_env__find_bpf_prog_info(dso->bpf_prog.env, dso->bpf_prog.id);
if (!node || !node->info_linear) {
dso->data.status = DSO_DATA_STATUS_ERROR;
return -1;
}
dso->data.file_size = node->info_linear->info.jited_prog_len;
return 0;
}
#endif // HAVE_LIBBPF_SUPPORT
static void
dso_cache__free(struct dso *dso)
{
struct rb_root *root = &dso->data.cache;
struct rb_node *next = rb_first(root);
pthread_mutex_lock(&dso->lock);
while (next) {
struct dso_cache *cache;
cache = rb_entry(next, struct dso_cache, rb_node);
next = rb_next(&cache->rb_node);
rb_erase(&cache->rb_node, root);
free(cache);
}
pthread_mutex_unlock(&dso->lock);
}
static struct dso_cache *__dso_cache__find(struct dso *dso, u64 offset)
{
const struct rb_root *root = &dso->data.cache;
struct rb_node * const *p = &root->rb_node;
const struct rb_node *parent = NULL;
struct dso_cache *cache;
while (*p != NULL) {
u64 end;
parent = *p;
cache = rb_entry(parent, struct dso_cache, rb_node);
end = cache->offset + DSO__DATA_CACHE_SIZE;
if (offset < cache->offset)
p = &(*p)->rb_left;
else if (offset >= end)
p = &(*p)->rb_right;
else
return cache;
}
return NULL;
}
static struct dso_cache *
dso_cache__insert(struct dso *dso, struct dso_cache *new)
{
struct rb_root *root = &dso->data.cache;
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
struct dso_cache *cache;
u64 offset = new->offset;
pthread_mutex_lock(&dso->lock);
while (*p != NULL) {
u64 end;
parent = *p;
cache = rb_entry(parent, struct dso_cache, rb_node);
end = cache->offset + DSO__DATA_CACHE_SIZE;
if (offset < cache->offset)
p = &(*p)->rb_left;
else if (offset >= end)
p = &(*p)->rb_right;
else
goto out;
}
rb_link_node(&new->rb_node, parent, p);
rb_insert_color(&new->rb_node, root);
cache = NULL;
out:
pthread_mutex_unlock(&dso->lock);
return cache;
}
static ssize_t dso_cache__memcpy(struct dso_cache *cache, u64 offset, u8 *data,
u64 size, bool out)
{
u64 cache_offset = offset - cache->offset;
u64 cache_size = min(cache->size - cache_offset, size);
if (out)
memcpy(data, cache->data + cache_offset, cache_size);
else
memcpy(cache->data + cache_offset, data, cache_size);
return cache_size;
}
static ssize_t file_read(struct dso *dso, struct machine *machine,
u64 offset, char *data)
{
ssize_t ret;
pthread_mutex_lock(&dso__data_open_lock);
/*
* dso->data.fd might be closed if other thread opened another
* file (dso) due to open file limit (RLIMIT_NOFILE).
*/
try_to_open_dso(dso, machine);
if (dso->data.fd < 0) {
dso->data.status = DSO_DATA_STATUS_ERROR;
ret = -errno;
goto out;
}
ret = pread(dso->data.fd, data, DSO__DATA_CACHE_SIZE, offset);
out:
pthread_mutex_unlock(&dso__data_open_lock);
return ret;
}
static struct dso_cache *dso_cache__populate(struct dso *dso,
struct machine *machine,
u64 offset, ssize_t *ret)
{
u64 cache_offset = offset & DSO__DATA_CACHE_MASK;
struct dso_cache *cache;
struct dso_cache *old;
cache = zalloc(sizeof(*cache) + DSO__DATA_CACHE_SIZE);
if (!cache) {
*ret = -ENOMEM;
return NULL;
}
#ifdef HAVE_LIBBPF_SUPPORT
if (dso->binary_type == DSO_BINARY_TYPE__BPF_PROG_INFO)
*ret = bpf_read(dso, cache_offset, cache->data);
else
#endif
if (dso->binary_type == DSO_BINARY_TYPE__OOL)
*ret = DSO__DATA_CACHE_SIZE;
else
*ret = file_read(dso, machine, cache_offset, cache->data);
if (*ret <= 0) {
free(cache);
return NULL;
}
cache->offset = cache_offset;
cache->size = *ret;
old = dso_cache__insert(dso, cache);
if (old) {
/* we lose the race */
free(cache);
cache = old;
}
return cache;
}
static struct dso_cache *dso_cache__find(struct dso *dso,
struct machine *machine,
u64 offset,
ssize_t *ret)
{
struct dso_cache *cache = __dso_cache__find(dso, offset);
return cache ? cache : dso_cache__populate(dso, machine, offset, ret);
}
static ssize_t dso_cache_io(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size, bool out)
{
struct dso_cache *cache;
ssize_t ret = 0;
cache = dso_cache__find(dso, machine, offset, &ret);
if (!cache)
return ret;
return dso_cache__memcpy(cache, offset, data, size, out);
}
/*
* Reads and caches dso data DSO__DATA_CACHE_SIZE size chunks
* in the rb_tree. Any read to already cached data is served
* by cached data. Writes update the cache only, not the backing file.
*/
static ssize_t cached_io(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size, bool out)
{
ssize_t r = 0;
u8 *p = data;
do {
ssize_t ret;
ret = dso_cache_io(dso, machine, offset, p, size, out);
if (ret < 0)
return ret;
/* Reached EOF, return what we have. */
if (!ret)
break;
BUG_ON(ret > size);
r += ret;
p += ret;
offset += ret;
size -= ret;
} while (size);
return r;
}
static int file_size(struct dso *dso, struct machine *machine)
{
int ret = 0;
struct stat st;
char sbuf[STRERR_BUFSIZE];
pthread_mutex_lock(&dso__data_open_lock);
/*
* dso->data.fd might be closed if other thread opened another
* file (dso) due to open file limit (RLIMIT_NOFILE).
*/
try_to_open_dso(dso, machine);
if (dso->data.fd < 0) {
ret = -errno;
dso->data.status = DSO_DATA_STATUS_ERROR;
goto out;
}
if (fstat(dso->data.fd, &st) < 0) {
ret = -errno;
pr_err("dso cache fstat failed: %s\n",
str_error_r(errno, sbuf, sizeof(sbuf)));
dso->data.status = DSO_DATA_STATUS_ERROR;
goto out;
}
dso->data.file_size = st.st_size;
out:
pthread_mutex_unlock(&dso__data_open_lock);
return ret;
}
int dso__data_file_size(struct dso *dso, struct machine *machine)
{
if (dso->data.file_size)
return 0;
if (dso->data.status == DSO_DATA_STATUS_ERROR)
return -1;
#ifdef HAVE_LIBBPF_SUPPORT
if (dso->binary_type == DSO_BINARY_TYPE__BPF_PROG_INFO)
return bpf_size(dso);
#endif
return file_size(dso, machine);
}
/**
* dso__data_size - Return dso data size
* @dso: dso object
* @machine: machine object
*
* Return: dso data size
*/
off_t dso__data_size(struct dso *dso, struct machine *machine)
{
if (dso__data_file_size(dso, machine))
return -1;
/* For now just estimate dso data size is close to file size */
return dso->data.file_size;
}
static ssize_t data_read_write_offset(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size,
bool out)
{
if (dso__data_file_size(dso, machine))
return -1;
/* Check the offset sanity. */
if (offset > dso->data.file_size)
return -1;
if (offset + size < offset)
return -1;
return cached_io(dso, machine, offset, data, size, out);
}
/**
* dso__data_read_offset - Read data from dso file offset
* @dso: dso object
* @machine: machine object
* @offset: file offset
* @data: buffer to store data
* @size: size of the @data buffer
*
* External interface to read data from dso file offset. Open
* dso data file and use cached_read to get the data.
*/
ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size)
{
if (dso->data.status == DSO_DATA_STATUS_ERROR)
return -1;
return data_read_write_offset(dso, machine, offset, data, size, true);
}
/**
* dso__data_read_addr - Read data from dso address
* @dso: dso object
* @machine: machine object
* @add: virtual memory address
* @data: buffer to store data
* @size: size of the @data buffer
*
* External interface to read data from dso address.
*/
ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
struct machine *machine, u64 addr,
u8 *data, ssize_t size)
{
u64 offset = map->map_ip(map, addr);
return dso__data_read_offset(dso, machine, offset, data, size);
}
/**
* dso__data_write_cache_offs - Write data to dso data cache at file offset
* @dso: dso object
* @machine: machine object
* @offset: file offset
* @data: buffer to write
* @size: size of the @data buffer
*
* Write into the dso file data cache, but do not change the file itself.
*/
ssize_t dso__data_write_cache_offs(struct dso *dso, struct machine *machine,
u64 offset, const u8 *data_in, ssize_t size)
{
u8 *data = (u8 *)data_in; /* cast away const to use same fns for r/w */
if (dso->data.status == DSO_DATA_STATUS_ERROR)
return -1;
return data_read_write_offset(dso, machine, offset, data, size, false);
}
/**
* dso__data_write_cache_addr - Write data to dso data cache at dso address
* @dso: dso object
* @machine: machine object
* @add: virtual memory address
* @data: buffer to write
* @size: size of the @data buffer
*
* External interface to write into the dso file data cache, but do not change
* the file itself.
*/
ssize_t dso__data_write_cache_addr(struct dso *dso, struct map *map,
struct machine *machine, u64 addr,
const u8 *data, ssize_t size)
{
u64 offset = map->map_ip(map, addr);
return dso__data_write_cache_offs(dso, machine, offset, data, size);
}
struct map *dso__new_map(const char *name)
{
struct map *map = NULL;
struct dso *dso = dso__new(name);
if (dso) {
map = map__new2(0, dso);
dso__put(dso);
}
return map;
}
struct dso *machine__findnew_kernel(struct machine *machine, const char *name,
const char *short_name, int dso_type)
{
/*
* The kernel dso could be created by build_id processing.
*/
struct dso *dso = machine__findnew_dso(machine, name);
/*
* We need to run this in all cases, since during the build_id
* processing we had no idea this was the kernel dso.
*/
if (dso != NULL) {
dso__set_short_name(dso, short_name, false);
dso->kernel = dso_type;
}
return dso;
}
static void dso__set_long_name_id(struct dso *dso, const char *name, struct dso_id *id, bool name_allocated)
{
struct rb_root *root = dso->root;
if (name == NULL)
return;
if (dso->long_name_allocated)
free((char *)dso->long_name);
if (root) {
rb_erase(&dso->rb_node, root);
/*
* __dsos__findnew_link_by_longname_id() isn't guaranteed to
* add it back, so a clean removal is required here.
*/
RB_CLEAR_NODE(&dso->rb_node);
dso->root = NULL;
}
dso->long_name = name;
dso->long_name_len = strlen(name);
dso->long_name_allocated = name_allocated;
if (root)
__dsos__findnew_link_by_longname_id(root, dso, NULL, id);
}
void dso__set_long_name(struct dso *dso, const char *name, bool name_allocated)
{
dso__set_long_name_id(dso, name, NULL, name_allocated);
}
void dso__set_short_name(struct dso *dso, const char *name, bool name_allocated)
{
if (name == NULL)
return;
if (dso->short_name_allocated)
free((char *)dso->short_name);
dso->short_name = name;
dso->short_name_len = strlen(name);
dso->short_name_allocated = name_allocated;
}
int dso__name_len(const struct dso *dso)
{
if (!dso)
return strlen("[unknown]");
if (verbose > 0)
return dso->long_name_len;
return dso->short_name_len;
}
bool dso__loaded(const struct dso *dso)
{
return dso->loaded;
}
bool dso__sorted_by_name(const struct dso *dso)
{
return dso->sorted_by_name;
}
void dso__set_sorted_by_name(struct dso *dso)
{
dso->sorted_by_name = true;
}
struct dso *dso__new_id(const char *name, struct dso_id *id)
{
struct dso *dso = calloc(1, sizeof(*dso) + strlen(name) + 1);
if (dso != NULL) {
strcpy(dso->name, name);
if (id)
dso->id = *id;
dso__set_long_name_id(dso, dso->name, id, false);
dso__set_short_name(dso, dso->name, false);
dso->symbols = dso->symbol_names = RB_ROOT_CACHED;
dso->data.cache = RB_ROOT;
dso->inlined_nodes = RB_ROOT_CACHED;
dso->srclines = RB_ROOT_CACHED;
dso->data.fd = -1;
dso->data.status = DSO_DATA_STATUS_UNKNOWN;
dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->binary_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->is_64_bit = (sizeof(void *) == 8);
dso->loaded = 0;
dso->rel = 0;
dso->sorted_by_name = 0;
dso->has_build_id = 0;
dso->has_srcline = 1;
dso->a2l_fails = 1;
dso->kernel = DSO_SPACE__USER;
dso->needs_swap = DSO_SWAP__UNSET;
dso->comp = COMP_ID__NONE;
RB_CLEAR_NODE(&dso->rb_node);
dso->root = NULL;
INIT_LIST_HEAD(&dso->node);
INIT_LIST_HEAD(&dso->data.open_entry);
pthread_mutex_init(&dso->lock, NULL);
refcount_set(&dso->refcnt, 1);
}
return dso;
}
struct dso *dso__new(const char *name)
{
return dso__new_id(name, NULL);
}
void dso__delete(struct dso *dso)
{
if (!RB_EMPTY_NODE(&dso->rb_node))
pr_err("DSO %s is still in rbtree when being deleted!\n",
dso->long_name);
/* free inlines first, as they reference symbols */
inlines__tree_delete(&dso->inlined_nodes);
srcline__tree_delete(&dso->srclines);
symbols__delete(&dso->symbols);
if (dso->short_name_allocated) {
zfree((char **)&dso->short_name);
dso->short_name_allocated = false;
}
if (dso->long_name_allocated) {
zfree((char **)&dso->long_name);
dso->long_name_allocated = false;
}
dso__data_close(dso);
auxtrace_cache__free(dso->auxtrace_cache);
dso_cache__free(dso);
dso__free_a2l(dso);
zfree(&dso->symsrc_filename);
nsinfo__zput(dso->nsinfo);
pthread_mutex_destroy(&dso->lock);
free(dso);
}
struct dso *dso__get(struct dso *dso)
{
if (dso)
refcount_inc(&dso->refcnt);
return dso;
}
void dso__put(struct dso *dso)
{
if (dso && refcount_dec_and_test(&dso->refcnt))
dso__delete(dso);
}
void dso__set_build_id(struct dso *dso, struct build_id *bid)
{
dso->bid = *bid;
dso->has_build_id = 1;
}
bool dso__build_id_equal(const struct dso *dso, struct build_id *bid)
{
if (dso->bid.size > bid->size && dso->bid.size == BUILD_ID_SIZE) {
/*
* For the backward compatibility, it allows a build-id has
* trailing zeros.
*/
return !memcmp(dso->bid.data, bid->data, bid->size) &&
!memchr_inv(&dso->bid.data[bid->size], 0,
dso->bid.size - bid->size);
}
return dso->bid.size == bid->size &&
memcmp(dso->bid.data, bid->data, dso->bid.size) == 0;
}
void dso__read_running_kernel_build_id(struct dso *dso, struct machine *machine)
{
char path[PATH_MAX];
if (machine__is_default_guest(machine))
return;
sprintf(path, "%s/sys/kernel/notes", machine->root_dir);
if (sysfs__read_build_id(path, &dso->bid) == 0)
dso->has_build_id = true;
}
int dso__kernel_module_get_build_id(struct dso *dso,
const char *root_dir)
{
char filename[PATH_MAX];
/*
* kernel module short names are of the form "[module]" and
* we need just "module" here.
*/
const char *name = dso->short_name + 1;
snprintf(filename, sizeof(filename),
"%s/sys/module/%.*s/notes/.note.gnu.build-id",
root_dir, (int)strlen(name) - 1, name);
if (sysfs__read_build_id(filename, &dso->bid) == 0)
dso->has_build_id = true;
return 0;
}
static size_t dso__fprintf_buildid(struct dso *dso, FILE *fp)
{
char sbuild_id[SBUILD_ID_SIZE];
build_id__sprintf(&dso->bid, sbuild_id);
return fprintf(fp, "%s", sbuild_id);
}
size_t dso__fprintf(struct dso *dso, FILE *fp)
{
struct rb_node *nd;
size_t ret = fprintf(fp, "dso: %s (", dso->short_name);
if (dso->short_name != dso->long_name)
ret += fprintf(fp, "%s, ", dso->long_name);
ret += fprintf(fp, "%sloaded, ", dso__loaded(dso) ? "" : "NOT ");
ret += dso__fprintf_buildid(dso, fp);
ret += fprintf(fp, ")\n");
for (nd = rb_first_cached(&dso->symbols); nd; nd = rb_next(nd)) {
struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
ret += symbol__fprintf(pos, fp);
}
return ret;
}
enum dso_type dso__type(struct dso *dso, struct machine *machine)
{
int fd;
enum dso_type type = DSO__TYPE_UNKNOWN;
fd = dso__data_get_fd(dso, machine);
if (fd >= 0) {
type = dso__type_fd(fd);
dso__data_put_fd(dso);
}
return type;
}
int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
{
int idx, errnum = dso->load_errno;
/*
* This must have a same ordering as the enum dso_load_errno.
*/
static const char *dso_load__error_str[] = {
"Internal tools/perf/ library error",
"Invalid ELF file",
"Can not read build id",
"Mismatching build id",
"Decompression failure",
};
BUG_ON(buflen == 0);
if (errnum >= 0) {
const char *err = str_error_r(errnum, buf, buflen);
if (err != buf)
scnprintf(buf, buflen, "%s", err);
return 0;
}
if (errnum < __DSO_LOAD_ERRNO__START || errnum >= __DSO_LOAD_ERRNO__END)
return -1;
idx = errnum - __DSO_LOAD_ERRNO__START;
scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
return 0;
}