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-rw-r--r--tools/lib/bpf/.gitignore2
-rw-r--r--tools/lib/bpf/Build1
-rw-r--r--tools/lib/bpf/Makefile195
-rw-r--r--tools/lib/bpf/bpf.c85
-rw-r--r--tools/lib/bpf/bpf.h23
-rw-r--r--tools/lib/bpf/libbpf.c1056
-rw-r--r--tools/lib/bpf/libbpf.h83
7 files changed, 1445 insertions, 0 deletions
diff --git a/tools/lib/bpf/.gitignore b/tools/lib/bpf/.gitignore
new file mode 100644
index 000000000..812aeedae
--- /dev/null
+++ b/tools/lib/bpf/.gitignore
@@ -0,0 +1,2 @@
+libbpf_version.h
+FEATURE-DUMP
diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build
new file mode 100644
index 000000000..d87497563
--- /dev/null
+++ b/tools/lib/bpf/Build
@@ -0,0 +1 @@
+libbpf-y := libbpf.o bpf.o
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
new file mode 100644
index 000000000..f68d23a0b
--- /dev/null
+++ b/tools/lib/bpf/Makefile
@@ -0,0 +1,195 @@
+# Most of this file is copied from tools/lib/traceevent/Makefile
+
+BPF_VERSION = 0
+BPF_PATCHLEVEL = 0
+BPF_EXTRAVERSION = 1
+
+MAKEFLAGS += --no-print-directory
+
+
+# Makefiles suck: This macro sets a default value of $(2) for the
+# variable named by $(1), unless the variable has been set by
+# environment or command line. This is necessary for CC and AR
+# because make sets default values, so the simpler ?= approach
+# won't work as expected.
+define allow-override
+ $(if $(or $(findstring environment,$(origin $(1))),\
+ $(findstring command line,$(origin $(1)))),,\
+ $(eval $(1) = $(2)))
+endef
+
+# Allow setting CC and AR, or setting CROSS_COMPILE as a prefix.
+$(call allow-override,CC,$(CROSS_COMPILE)gcc)
+$(call allow-override,AR,$(CROSS_COMPILE)ar)
+
+INSTALL = install
+
+# Use DESTDIR for installing into a different root directory.
+# This is useful for building a package. The program will be
+# installed in this directory as if it was the root directory.
+# Then the build tool can move it later.
+DESTDIR ?=
+DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'
+
+LP64 := $(shell echo __LP64__ | ${CC} ${CFLAGS} -E -x c - | tail -n 1)
+ifeq ($(LP64), 1)
+ libdir_relative = lib64
+else
+ libdir_relative = lib
+endif
+
+prefix ?= /usr/local
+libdir = $(prefix)/$(libdir_relative)
+man_dir = $(prefix)/share/man
+man_dir_SQ = '$(subst ','\'',$(man_dir))'
+
+export man_dir man_dir_SQ INSTALL
+export DESTDIR DESTDIR_SQ
+
+include ../../scripts/Makefile.include
+
+# copy a bit from Linux kbuild
+
+ifeq ("$(origin V)", "command line")
+ VERBOSE = $(V)
+endif
+ifndef VERBOSE
+ VERBOSE = 0
+endif
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(shell pwd)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+#$(info Determined 'srctree' to be $(srctree))
+endif
+
+FEATURE_DISPLAY = libelf libelf-getphdrnum libelf-mmap bpf
+FEATURE_TESTS = libelf bpf
+
+INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/arch/$(ARCH)/include/uapi -I$(srctree)/include/uapi
+FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)
+
+include $(srctree)/tools/build/Makefile.feature
+
+export prefix libdir src obj
+
+# Shell quotes
+libdir_SQ = $(subst ','\'',$(libdir))
+libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
+plugin_dir_SQ = $(subst ','\'',$(plugin_dir))
+
+LIB_FILE = libbpf.a libbpf.so
+
+VERSION = $(BPF_VERSION)
+PATCHLEVEL = $(BPF_PATCHLEVEL)
+EXTRAVERSION = $(BPF_EXTRAVERSION)
+
+OBJ = $@
+N =
+
+LIBBPF_VERSION = $(BPF_VERSION).$(BPF_PATCHLEVEL).$(BPF_EXTRAVERSION)
+
+# Set compile option CFLAGS
+ifdef EXTRA_CFLAGS
+ CFLAGS := $(EXTRA_CFLAGS)
+else
+ CFLAGS := -g -Wall
+endif
+
+ifeq ($(feature-libelf-mmap), 1)
+ override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
+endif
+
+ifeq ($(feature-libelf-getphdrnum), 1)
+ override CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
+endif
+
+# Append required CFLAGS
+override CFLAGS += $(EXTRA_WARNINGS)
+override CFLAGS += -Werror -Wall
+override CFLAGS += -fPIC
+override CFLAGS += $(INCLUDES)
+
+ifeq ($(VERBOSE),1)
+ Q =
+else
+ Q = @
+endif
+
+# Disable command line variables (CFLAGS) overide from top
+# level Makefile (perf), otherwise build Makefile will get
+# the same command line setup.
+MAKEOVERRIDES=
+
+export srctree OUTPUT CC LD CFLAGS V
+build := -f $(srctree)/tools/build/Makefile.build dir=. obj
+
+BPF_IN := $(OUTPUT)libbpf-in.o
+LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
+
+CMD_TARGETS = $(LIB_FILE)
+
+TARGETS = $(CMD_TARGETS)
+
+all: $(VERSION_FILES) all_cmd
+
+all_cmd: $(CMD_TARGETS)
+
+$(BPF_IN): force elfdep bpfdep
+ $(Q)$(MAKE) $(build)=libbpf
+
+$(OUTPUT)libbpf.so: $(BPF_IN)
+ $(QUIET_LINK)$(CC) --shared $^ -o $@
+
+$(OUTPUT)libbpf.a: $(BPF_IN)
+ $(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
+
+define update_dir
+ (echo $1 > $@.tmp; \
+ if [ -r $@ ] && cmp -s $@ $@.tmp; then \
+ rm -f $@.tmp; \
+ else \
+ echo ' UPDATE $@'; \
+ mv -f $@.tmp $@; \
+ fi);
+endef
+
+define do_install
+ if [ ! -d '$(DESTDIR_SQ)$2' ]; then \
+ $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
+ fi; \
+ $(INSTALL) $1 '$(DESTDIR_SQ)$2'
+endef
+
+install_lib: all_cmd
+ $(call QUIET_INSTALL, $(LIB_FILE)) \
+ $(call do_install,$(LIB_FILE),$(libdir_SQ))
+
+install: install_lib
+
+### Cleaning rules
+
+config-clean:
+ $(call QUIET_CLEAN, config)
+ $(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
+
+clean:
+ $(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so $(VERSION_FILES) .*.d \
+ $(RM) LIBBPF-CFLAGS
+ $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP
+
+
+
+PHONY += force elfdep bpfdep
+force:
+
+elfdep:
+ @if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit -1 ; fi
+
+bpfdep:
+ @if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit -1 ; fi
+
+# Declare the contents of the .PHONY variable as phony. We keep that
+# information in a variable so we can use it in if_changed and friends.
+.PHONY: $(PHONY)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
new file mode 100644
index 000000000..a6331050a
--- /dev/null
+++ b/tools/lib/bpf/bpf.c
@@ -0,0 +1,85 @@
+/*
+ * common eBPF ELF operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+
+#include <stdlib.h>
+#include <memory.h>
+#include <unistd.h>
+#include <asm/unistd.h>
+#include <linux/bpf.h>
+#include "bpf.h"
+
+/*
+ * When building perf, unistd.h is override. Define __NR_bpf is
+ * required to be defined.
+ */
+#ifndef __NR_bpf
+# if defined(__i386__)
+# define __NR_bpf 357
+# elif defined(__x86_64__)
+# define __NR_bpf 321
+# elif defined(__aarch64__)
+# define __NR_bpf 280
+# else
+# error __NR_bpf not defined. libbpf does not support your arch.
+# endif
+#endif
+
+static __u64 ptr_to_u64(void *ptr)
+{
+ return (__u64) (unsigned long) ptr;
+}
+
+static int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
+ unsigned int size)
+{
+ return syscall(__NR_bpf, cmd, attr, size);
+}
+
+int bpf_create_map(enum bpf_map_type map_type, int key_size,
+ int value_size, int max_entries)
+{
+ union bpf_attr attr;
+
+ memset(&attr, '\0', sizeof(attr));
+
+ attr.map_type = map_type;
+ attr.key_size = key_size;
+ attr.value_size = value_size;
+ attr.max_entries = max_entries;
+
+ return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
+}
+
+int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
+ size_t insns_cnt, char *license,
+ u32 kern_version, char *log_buf, size_t log_buf_sz)
+{
+ int fd;
+ union bpf_attr attr;
+
+ bzero(&attr, sizeof(attr));
+ attr.prog_type = type;
+ attr.insn_cnt = (__u32)insns_cnt;
+ attr.insns = ptr_to_u64(insns);
+ attr.license = ptr_to_u64(license);
+ attr.log_buf = ptr_to_u64(NULL);
+ attr.log_size = 0;
+ attr.log_level = 0;
+ attr.kern_version = kern_version;
+
+ fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
+ if (fd >= 0 || !log_buf || !log_buf_sz)
+ return fd;
+
+ /* Try again with log */
+ attr.log_buf = ptr_to_u64(log_buf);
+ attr.log_size = log_buf_sz;
+ attr.log_level = 1;
+ log_buf[0] = 0;
+ return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
+}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
new file mode 100644
index 000000000..854b7361b
--- /dev/null
+++ b/tools/lib/bpf/bpf.h
@@ -0,0 +1,23 @@
+/*
+ * common eBPF ELF operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+#ifndef __BPF_BPF_H
+#define __BPF_BPF_H
+
+#include <linux/bpf.h>
+
+int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
+ int max_entries);
+
+/* Recommend log buffer size */
+#define BPF_LOG_BUF_SIZE 65536
+int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
+ size_t insns_cnt, char *license,
+ u32 kern_version, char *log_buf,
+ size_t log_buf_sz);
+
+#endif
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
new file mode 100644
index 000000000..4252fc22f
--- /dev/null
+++ b/tools/lib/bpf/libbpf.c
@@ -0,0 +1,1056 @@
+/*
+ * Common eBPF ELF object loading operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <inttypes.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <asm/unistd.h>
+#include <linux/kernel.h>
+#include <linux/bpf.h>
+#include <linux/list.h>
+#include <libelf.h>
+#include <gelf.h>
+
+#include "libbpf.h"
+#include "bpf.h"
+
+#define __printf(a, b) __attribute__((format(printf, a, b)))
+
+__printf(1, 2)
+static int __base_pr(const char *format, ...)
+{
+ va_list args;
+ int err;
+
+ va_start(args, format);
+ err = vfprintf(stderr, format, args);
+ va_end(args);
+ return err;
+}
+
+static __printf(1, 2) libbpf_print_fn_t __pr_warning = __base_pr;
+static __printf(1, 2) libbpf_print_fn_t __pr_info = __base_pr;
+static __printf(1, 2) libbpf_print_fn_t __pr_debug;
+
+#define __pr(func, fmt, ...) \
+do { \
+ if ((func)) \
+ (func)("libbpf: " fmt, ##__VA_ARGS__); \
+} while (0)
+
+#define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__)
+#define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__)
+#define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__)
+
+void libbpf_set_print(libbpf_print_fn_t warn,
+ libbpf_print_fn_t info,
+ libbpf_print_fn_t debug)
+{
+ __pr_warning = warn;
+ __pr_info = info;
+ __pr_debug = debug;
+}
+
+/* Copied from tools/perf/util/util.h */
+#ifndef zfree
+# define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
+#endif
+
+#ifndef zclose
+# define zclose(fd) ({ \
+ int ___err = 0; \
+ if ((fd) >= 0) \
+ ___err = close((fd)); \
+ fd = -1; \
+ ___err; })
+#endif
+
+#ifdef HAVE_LIBELF_MMAP_SUPPORT
+# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP
+#else
+# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ
+#endif
+
+/*
+ * bpf_prog should be a better name but it has been used in
+ * linux/filter.h.
+ */
+struct bpf_program {
+ /* Index in elf obj file, for relocation use. */
+ int idx;
+ char *section_name;
+ struct bpf_insn *insns;
+ size_t insns_cnt;
+
+ struct {
+ int insn_idx;
+ int map_idx;
+ } *reloc_desc;
+ int nr_reloc;
+
+ int fd;
+
+ struct bpf_object *obj;
+ void *priv;
+ bpf_program_clear_priv_t clear_priv;
+};
+
+static LIST_HEAD(bpf_objects_list);
+
+struct bpf_object {
+ char license[64];
+ u32 kern_version;
+ void *maps_buf;
+ size_t maps_buf_sz;
+
+ struct bpf_program *programs;
+ size_t nr_programs;
+ int *map_fds;
+ /*
+ * This field is required because maps_buf will be freed and
+ * maps_buf_sz will be set to 0 after loaded.
+ */
+ size_t nr_map_fds;
+ bool loaded;
+
+ /*
+ * Information when doing elf related work. Only valid if fd
+ * is valid.
+ */
+ struct {
+ int fd;
+ void *obj_buf;
+ size_t obj_buf_sz;
+ Elf *elf;
+ GElf_Ehdr ehdr;
+ Elf_Data *symbols;
+ struct {
+ GElf_Shdr shdr;
+ Elf_Data *data;
+ } *reloc;
+ int nr_reloc;
+ } efile;
+ /*
+ * All loaded bpf_object is linked in a list, which is
+ * hidden to caller. bpf_objects__<func> handlers deal with
+ * all objects.
+ */
+ struct list_head list;
+ char path[];
+};
+#define obj_elf_valid(o) ((o)->efile.elf)
+
+static void bpf_program__unload(struct bpf_program *prog)
+{
+ if (!prog)
+ return;
+
+ zclose(prog->fd);
+}
+
+static void bpf_program__exit(struct bpf_program *prog)
+{
+ if (!prog)
+ return;
+
+ if (prog->clear_priv)
+ prog->clear_priv(prog, prog->priv);
+
+ prog->priv = NULL;
+ prog->clear_priv = NULL;
+
+ bpf_program__unload(prog);
+ zfree(&prog->section_name);
+ zfree(&prog->insns);
+ zfree(&prog->reloc_desc);
+
+ prog->nr_reloc = 0;
+ prog->insns_cnt = 0;
+ prog->idx = -1;
+}
+
+static int
+bpf_program__init(void *data, size_t size, char *name, int idx,
+ struct bpf_program *prog)
+{
+ if (size < sizeof(struct bpf_insn)) {
+ pr_warning("corrupted section '%s'\n", name);
+ return -EINVAL;
+ }
+
+ bzero(prog, sizeof(*prog));
+
+ prog->section_name = strdup(name);
+ if (!prog->section_name) {
+ pr_warning("failed to alloc name for prog %s\n",
+ name);
+ goto errout;
+ }
+
+ prog->insns = malloc(size);
+ if (!prog->insns) {
+ pr_warning("failed to alloc insns for %s\n", name);
+ goto errout;
+ }
+ prog->insns_cnt = size / sizeof(struct bpf_insn);
+ memcpy(prog->insns, data,
+ prog->insns_cnt * sizeof(struct bpf_insn));
+ prog->idx = idx;
+ prog->fd = -1;
+
+ return 0;
+errout:
+ bpf_program__exit(prog);
+ return -ENOMEM;
+}
+
+static int
+bpf_object__add_program(struct bpf_object *obj, void *data, size_t size,
+ char *name, int idx)
+{
+ struct bpf_program prog, *progs;
+ int nr_progs, err;
+
+ err = bpf_program__init(data, size, name, idx, &prog);
+ if (err)
+ return err;
+
+ progs = obj->programs;
+ nr_progs = obj->nr_programs;
+
+ progs = realloc(progs, sizeof(progs[0]) * (nr_progs + 1));
+ if (!progs) {
+ /*
+ * In this case the original obj->programs
+ * is still valid, so don't need special treat for
+ * bpf_close_object().
+ */
+ pr_warning("failed to alloc a new program '%s'\n",
+ name);
+ bpf_program__exit(&prog);
+ return -ENOMEM;
+ }
+
+ pr_debug("found program %s\n", prog.section_name);
+ obj->programs = progs;
+ obj->nr_programs = nr_progs + 1;
+ prog.obj = obj;
+ progs[nr_progs] = prog;
+ return 0;
+}
+
+static struct bpf_object *bpf_object__new(const char *path,
+ void *obj_buf,
+ size_t obj_buf_sz)
+{
+ struct bpf_object *obj;
+
+ obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1);
+ if (!obj) {
+ pr_warning("alloc memory failed for %s\n", path);
+ return NULL;
+ }
+
+ strcpy(obj->path, path);
+ obj->efile.fd = -1;
+
+ /*
+ * Caller of this function should also calls
+ * bpf_object__elf_finish() after data collection to return
+ * obj_buf to user. If not, we should duplicate the buffer to
+ * avoid user freeing them before elf finish.
+ */
+ obj->efile.obj_buf = obj_buf;
+ obj->efile.obj_buf_sz = obj_buf_sz;
+
+ obj->loaded = false;
+
+ INIT_LIST_HEAD(&obj->list);
+ list_add(&obj->list, &bpf_objects_list);
+ return obj;
+}
+
+static void bpf_object__elf_finish(struct bpf_object *obj)
+{
+ if (!obj_elf_valid(obj))
+ return;
+
+ if (obj->efile.elf) {
+ elf_end(obj->efile.elf);
+ obj->efile.elf = NULL;
+ }
+ obj->efile.symbols = NULL;
+
+ zfree(&obj->efile.reloc);
+ obj->efile.nr_reloc = 0;
+ zclose(obj->efile.fd);
+ obj->efile.obj_buf = NULL;
+ obj->efile.obj_buf_sz = 0;
+}
+
+static int bpf_object__elf_init(struct bpf_object *obj)
+{
+ int err = 0;
+ GElf_Ehdr *ep;
+
+ if (obj_elf_valid(obj)) {
+ pr_warning("elf init: internal error\n");
+ return -EEXIST;
+ }
+
+ if (obj->efile.obj_buf_sz > 0) {
+ /*
+ * obj_buf should have been validated by
+ * bpf_object__open_buffer().
+ */
+ obj->efile.elf = elf_memory(obj->efile.obj_buf,
+ obj->efile.obj_buf_sz);
+ } else {
+ obj->efile.fd = open(obj->path, O_RDONLY);
+ if (obj->efile.fd < 0) {
+ pr_warning("failed to open %s: %s\n", obj->path,
+ strerror(errno));
+ return -errno;
+ }
+
+ obj->efile.elf = elf_begin(obj->efile.fd,
+ LIBBPF_ELF_C_READ_MMAP,
+ NULL);
+ }
+
+ if (!obj->efile.elf) {
+ pr_warning("failed to open %s as ELF file\n",
+ obj->path);
+ err = -EINVAL;
+ goto errout;
+ }
+
+ if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) {
+ pr_warning("failed to get EHDR from %s\n",
+ obj->path);
+ err = -EINVAL;
+ goto errout;
+ }
+ ep = &obj->efile.ehdr;
+
+ if ((ep->e_type != ET_REL) || (ep->e_machine != 0)) {
+ pr_warning("%s is not an eBPF object file\n",
+ obj->path);
+ err = -EINVAL;
+ goto errout;
+ }
+
+ return 0;
+errout:
+ bpf_object__elf_finish(obj);
+ return err;
+}
+
+static int
+bpf_object__check_endianness(struct bpf_object *obj)
+{
+ static unsigned int const endian = 1;
+
+ switch (obj->efile.ehdr.e_ident[EI_DATA]) {
+ case ELFDATA2LSB:
+ /* We are big endian, BPF obj is little endian. */
+ if (*(unsigned char const *)&endian != 1)
+ goto mismatch;
+ break;
+
+ case ELFDATA2MSB:
+ /* We are little endian, BPF obj is big endian. */
+ if (*(unsigned char const *)&endian != 0)
+ goto mismatch;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+
+mismatch:
+ pr_warning("Error: endianness mismatch.\n");
+ return -EINVAL;
+}
+
+static int
+bpf_object__init_license(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ memcpy(obj->license, data,
+ min(size, sizeof(obj->license) - 1));
+ pr_debug("license of %s is %s\n", obj->path, obj->license);
+ return 0;
+}
+
+static int
+bpf_object__init_kversion(struct bpf_object *obj,
+ void *data, size_t size)
+{
+ u32 kver;
+
+ if (size != sizeof(kver)) {
+ pr_warning("invalid kver section in %s\n", obj->path);
+ return -EINVAL;
+ }
+ memcpy(&kver, data, sizeof(kver));
+ obj->kern_version = kver;
+ pr_debug("kernel version of %s is %x\n", obj->path,
+ obj->kern_version);
+ return 0;
+}
+
+static int
+bpf_object__init_maps(struct bpf_object *obj, void *data,
+ size_t size)
+{
+ if (size == 0) {
+ pr_debug("%s doesn't need map definition\n",
+ obj->path);
+ return 0;
+ }
+
+ obj->maps_buf = malloc(size);
+ if (!obj->maps_buf) {
+ pr_warning("malloc maps failed: %s\n", obj->path);
+ return -ENOMEM;
+ }
+
+ obj->maps_buf_sz = size;
+ memcpy(obj->maps_buf, data, size);
+ pr_debug("maps in %s: %ld bytes\n", obj->path, (long)size);
+ return 0;
+}
+
+static int bpf_object__elf_collect(struct bpf_object *obj)
+{
+ Elf *elf = obj->efile.elf;
+ GElf_Ehdr *ep = &obj->efile.ehdr;
+ Elf_Scn *scn = NULL;
+ int idx = 0, err = 0;
+
+ /* Elf is corrupted/truncated, avoid calling elf_strptr. */
+ if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) {
+ pr_warning("failed to get e_shstrndx from %s\n",
+ obj->path);
+ return -EINVAL;
+ }
+
+ while ((scn = elf_nextscn(elf, scn)) != NULL) {
+ char *name;
+ GElf_Shdr sh;
+ Elf_Data *data;
+
+ idx++;
+ if (gelf_getshdr(scn, &sh) != &sh) {
+ pr_warning("failed to get section header from %s\n",
+ obj->path);
+ err = -EINVAL;
+ goto out;
+ }
+
+ name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name);
+ if (!name) {
+ pr_warning("failed to get section name from %s\n",
+ obj->path);
+ err = -EINVAL;
+ goto out;
+ }
+
+ data = elf_getdata(scn, 0);
+ if (!data) {
+ pr_warning("failed to get section data from %s(%s)\n",
+ name, obj->path);
+ err = -EINVAL;
+ goto out;
+ }
+ pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n",
+ name, (unsigned long)data->d_size,
+ (int)sh.sh_link, (unsigned long)sh.sh_flags,
+ (int)sh.sh_type);
+
+ if (strcmp(name, "license") == 0)
+ err = bpf_object__init_license(obj,
+ data->d_buf,
+ data->d_size);
+ else if (strcmp(name, "version") == 0)
+ err = bpf_object__init_kversion(obj,
+ data->d_buf,
+ data->d_size);
+ else if (strcmp(name, "maps") == 0)
+ err = bpf_object__init_maps(obj, data->d_buf,
+ data->d_size);
+ else if (sh.sh_type == SHT_SYMTAB) {
+ if (obj->efile.symbols) {
+ pr_warning("bpf: multiple SYMTAB in %s\n",
+ obj->path);
+ err = -EEXIST;
+ } else
+ obj->efile.symbols = data;
+ } else if ((sh.sh_type == SHT_PROGBITS) &&
+ (sh.sh_flags & SHF_EXECINSTR) &&
+ (data->d_size > 0)) {
+ err = bpf_object__add_program(obj, data->d_buf,
+ data->d_size, name, idx);
+ if (err) {
+ char errmsg[128];
+ strerror_r(-err, errmsg, sizeof(errmsg));
+ pr_warning("failed to alloc program %s (%s): %s",
+ name, obj->path, errmsg);
+ }
+ } else if (sh.sh_type == SHT_REL) {
+ void *reloc = obj->efile.reloc;
+ int nr_reloc = obj->efile.nr_reloc + 1;
+
+ reloc = realloc(reloc,
+ sizeof(*obj->efile.reloc) * nr_reloc);
+ if (!reloc) {
+ pr_warning("realloc failed\n");
+ err = -ENOMEM;
+ } else {
+ int n = nr_reloc - 1;
+
+ obj->efile.reloc = reloc;
+ obj->efile.nr_reloc = nr_reloc;
+
+ obj->efile.reloc[n].shdr = sh;
+ obj->efile.reloc[n].data = data;
+ }
+ }
+ if (err)
+ goto out;
+ }
+out:
+ return err;
+}
+
+static struct bpf_program *
+bpf_object__find_prog_by_idx(struct bpf_object *obj, int idx)
+{
+ struct bpf_program *prog;
+ size_t i;
+
+ for (i = 0; i < obj->nr_programs; i++) {
+ prog = &obj->programs[i];
+ if (prog->idx == idx)
+ return prog;
+ }
+ return NULL;
+}
+
+static int
+bpf_program__collect_reloc(struct bpf_program *prog,
+ size_t nr_maps, GElf_Shdr *shdr,
+ Elf_Data *data, Elf_Data *symbols)
+{
+ int i, nrels;
+
+ pr_debug("collecting relocating info for: '%s'\n",
+ prog->section_name);
+ nrels = shdr->sh_size / shdr->sh_entsize;
+
+ prog->reloc_desc = malloc(sizeof(*prog->reloc_desc) * nrels);
+ if (!prog->reloc_desc) {
+ pr_warning("failed to alloc memory in relocation\n");
+ return -ENOMEM;
+ }
+ prog->nr_reloc = nrels;
+
+ for (i = 0; i < nrels; i++) {
+ GElf_Sym sym;
+ GElf_Rel rel;
+ unsigned int insn_idx;
+ struct bpf_insn *insns = prog->insns;
+ size_t map_idx;
+
+ if (!gelf_getrel(data, i, &rel)) {
+ pr_warning("relocation: failed to get %d reloc\n", i);
+ return -EINVAL;
+ }
+
+ insn_idx = rel.r_offset / sizeof(struct bpf_insn);
+ pr_debug("relocation: insn_idx=%u\n", insn_idx);
+
+ if (!gelf_getsym(symbols,
+ GELF_R_SYM(rel.r_info),
+ &sym)) {
+ pr_warning("relocation: symbol %"PRIx64" not found\n",
+ GELF_R_SYM(rel.r_info));
+ return -EINVAL;
+ }
+
+ if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) {
+ pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n",
+ insn_idx, insns[insn_idx].code);
+ return -EINVAL;
+ }
+
+ map_idx = sym.st_value / sizeof(struct bpf_map_def);
+ if (map_idx >= nr_maps) {
+ pr_warning("bpf relocation: map_idx %d large than %d\n",
+ (int)map_idx, (int)nr_maps - 1);
+ return -EINVAL;
+ }
+
+ prog->reloc_desc[i].insn_idx = insn_idx;
+ prog->reloc_desc[i].map_idx = map_idx;
+ }
+ return 0;
+}
+
+static int
+bpf_object__create_maps(struct bpf_object *obj)
+{
+ unsigned int i;
+ size_t nr_maps;
+ int *pfd;
+
+ nr_maps = obj->maps_buf_sz / sizeof(struct bpf_map_def);
+ if (!obj->maps_buf || !nr_maps) {
+ pr_debug("don't need create maps for %s\n",
+ obj->path);
+ return 0;
+ }
+
+ obj->map_fds = malloc(sizeof(int) * nr_maps);
+ if (!obj->map_fds) {
+ pr_warning("realloc perf_bpf_map_fds failed\n");
+ return -ENOMEM;
+ }
+ obj->nr_map_fds = nr_maps;
+
+ /* fill all fd with -1 */
+ memset(obj->map_fds, -1, sizeof(int) * nr_maps);
+
+ pfd = obj->map_fds;
+ for (i = 0; i < nr_maps; i++) {
+ struct bpf_map_def def;
+
+ def = *(struct bpf_map_def *)(obj->maps_buf +
+ i * sizeof(struct bpf_map_def));
+
+ *pfd = bpf_create_map(def.type,
+ def.key_size,
+ def.value_size,
+ def.max_entries);
+ if (*pfd < 0) {
+ size_t j;
+ int err = *pfd;
+
+ pr_warning("failed to create map: %s\n",
+ strerror(errno));
+ for (j = 0; j < i; j++)
+ zclose(obj->map_fds[j]);
+ obj->nr_map_fds = 0;
+ zfree(&obj->map_fds);
+ return err;
+ }
+ pr_debug("create map: fd=%d\n", *pfd);
+ pfd++;
+ }
+
+ zfree(&obj->maps_buf);
+ obj->maps_buf_sz = 0;
+ return 0;
+}
+
+static int
+bpf_program__relocate(struct bpf_program *prog, int *map_fds)
+{
+ int i;
+
+ if (!prog || !prog->reloc_desc)
+ return 0;
+
+ for (i = 0; i < prog->nr_reloc; i++) {
+ int insn_idx, map_idx;
+ struct bpf_insn *insns = prog->insns;
+
+ insn_idx = prog->reloc_desc[i].insn_idx;
+ map_idx = prog->reloc_desc[i].map_idx;
+
+ if (insn_idx >= (int)prog->insns_cnt) {
+ pr_warning("relocation out of range: '%s'\n",
+ prog->section_name);
+ return -ERANGE;
+ }
+ insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
+ insns[insn_idx].imm = map_fds[map_idx];
+ }
+
+ zfree(&prog->reloc_desc);
+ prog->nr_reloc = 0;
+ return 0;
+}
+
+
+static int
+bpf_object__relocate(struct bpf_object *obj)
+{
+ struct bpf_program *prog;
+ size_t i;
+ int err;
+
+ for (i = 0; i < obj->nr_programs; i++) {
+ prog = &obj->programs[i];
+
+ err = bpf_program__relocate(prog, obj->map_fds);
+ if (err) {
+ pr_warning("failed to relocate '%s'\n",
+ prog->section_name);
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int bpf_object__collect_reloc(struct bpf_object *obj)
+{
+ int i, err;
+
+ if (!obj_elf_valid(obj)) {
+ pr_warning("Internal error: elf object is closed\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < obj->efile.nr_reloc; i++) {
+ GElf_Shdr *shdr = &obj->efile.reloc[i].shdr;
+ Elf_Data *data = obj->efile.reloc[i].data;
+ int idx = shdr->sh_info;
+ struct bpf_program *prog;
+ size_t nr_maps = obj->maps_buf_sz /
+ sizeof(struct bpf_map_def);
+
+ if (shdr->sh_type != SHT_REL) {
+ pr_warning("internal error at %d\n", __LINE__);
+ return -EINVAL;
+ }
+
+ prog = bpf_object__find_prog_by_idx(obj, idx);
+ if (!prog) {
+ pr_warning("relocation failed: no %d section\n",
+ idx);
+ return -ENOENT;
+ }
+
+ err = bpf_program__collect_reloc(prog, nr_maps,
+ shdr, data,
+ obj->efile.symbols);
+ if (err)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int
+load_program(struct bpf_insn *insns, int insns_cnt,
+ char *license, u32 kern_version, int *pfd)
+{
+ int ret;
+ char *log_buf;
+
+ if (!insns || !insns_cnt)
+ return -EINVAL;
+
+ log_buf = malloc(BPF_LOG_BUF_SIZE);
+ if (!log_buf)
+ pr_warning("Alloc log buffer for bpf loader error, continue without log\n");
+
+ ret = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
+ insns_cnt, license, kern_version,
+ log_buf, BPF_LOG_BUF_SIZE);
+
+ if (ret >= 0) {
+ *pfd = ret;
+ ret = 0;
+ goto out;
+ }
+
+ ret = -EINVAL;
+ pr_warning("load bpf program failed: %s\n", strerror(errno));
+
+ if (log_buf) {
+ pr_warning("-- BEGIN DUMP LOG ---\n");
+ pr_warning("\n%s\n", log_buf);
+ pr_warning("-- END LOG --\n");
+ }
+
+out:
+ free(log_buf);
+ return ret;
+}
+
+static int
+bpf_program__load(struct bpf_program *prog,
+ char *license, u32 kern_version)
+{
+ int err, fd;
+
+ err = load_program(prog->insns, prog->insns_cnt,
+ license, kern_version, &fd);
+ if (!err)
+ prog->fd = fd;
+
+ if (err)
+ pr_warning("failed to load program '%s'\n",
+ prog->section_name);
+ zfree(&prog->insns);
+ prog->insns_cnt = 0;
+ return err;
+}
+
+static int
+bpf_object__load_progs(struct bpf_object *obj)
+{
+ size_t i;
+ int err;
+
+ for (i = 0; i < obj->nr_programs; i++) {
+ err = bpf_program__load(&obj->programs[i],
+ obj->license,
+ obj->kern_version);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+static int bpf_object__validate(struct bpf_object *obj)
+{
+ if (obj->kern_version == 0) {
+ pr_warning("%s doesn't provide kernel version\n",
+ obj->path);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct bpf_object *
+__bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz)
+{
+ struct bpf_object *obj;
+
+ if (elf_version(EV_CURRENT) == EV_NONE) {
+ pr_warning("failed to init libelf for %s\n", path);
+ return NULL;
+ }
+
+ obj = bpf_object__new(path, obj_buf, obj_buf_sz);
+ if (!obj)
+ return NULL;
+
+ if (bpf_object__elf_init(obj))
+ goto out;
+ if (bpf_object__check_endianness(obj))
+ goto out;
+ if (bpf_object__elf_collect(obj))
+ goto out;
+ if (bpf_object__collect_reloc(obj))
+ goto out;
+ if (bpf_object__validate(obj))
+ goto out;
+
+ bpf_object__elf_finish(obj);
+ return obj;
+out:
+ bpf_object__close(obj);
+ return NULL;
+}
+
+struct bpf_object *bpf_object__open(const char *path)
+{
+ /* param validation */
+ if (!path)
+ return NULL;
+
+ pr_debug("loading %s\n", path);
+
+ return __bpf_object__open(path, NULL, 0);
+}
+
+struct bpf_object *bpf_object__open_buffer(void *obj_buf,
+ size_t obj_buf_sz,
+ const char *name)
+{
+ char tmp_name[64];
+
+ /* param validation */
+ if (!obj_buf || obj_buf_sz <= 0)
+ return NULL;
+
+ if (!name) {
+ snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx",
+ (unsigned long)obj_buf,
+ (unsigned long)obj_buf_sz);
+ tmp_name[sizeof(tmp_name) - 1] = '\0';
+ name = tmp_name;
+ }
+ pr_debug("loading object '%s' from buffer\n",
+ name);
+
+ return __bpf_object__open(name, obj_buf, obj_buf_sz);
+}
+
+int bpf_object__unload(struct bpf_object *obj)
+{
+ size_t i;
+
+ if (!obj)
+ return -EINVAL;
+
+ for (i = 0; i < obj->nr_map_fds; i++)
+ zclose(obj->map_fds[i]);
+ zfree(&obj->map_fds);
+ obj->nr_map_fds = 0;
+
+ for (i = 0; i < obj->nr_programs; i++)
+ bpf_program__unload(&obj->programs[i]);
+
+ return 0;
+}
+
+int bpf_object__load(struct bpf_object *obj)
+{
+ if (!obj)
+ return -EINVAL;
+
+ if (obj->loaded) {
+ pr_warning("object should not be loaded twice\n");
+ return -EINVAL;
+ }
+
+ obj->loaded = true;
+ if (bpf_object__create_maps(obj))
+ goto out;
+ if (bpf_object__relocate(obj))
+ goto out;
+ if (bpf_object__load_progs(obj))
+ goto out;
+
+ return 0;
+out:
+ bpf_object__unload(obj);
+ pr_warning("failed to load object '%s'\n", obj->path);
+ return -EINVAL;
+}
+
+void bpf_object__close(struct bpf_object *obj)
+{
+ size_t i;
+
+ if (!obj)
+ return;
+
+ bpf_object__elf_finish(obj);
+ bpf_object__unload(obj);
+
+ zfree(&obj->maps_buf);
+
+ if (obj->programs && obj->nr_programs) {
+ for (i = 0; i < obj->nr_programs; i++)
+ bpf_program__exit(&obj->programs[i]);
+ }
+ zfree(&obj->programs);
+
+ list_del(&obj->list);
+ free(obj);
+}
+
+struct bpf_object *
+bpf_object__next(struct bpf_object *prev)
+{
+ struct bpf_object *next;
+
+ if (!prev)
+ next = list_first_entry(&bpf_objects_list,
+ struct bpf_object,
+ list);
+ else
+ next = list_next_entry(prev, list);
+
+ /* Empty list is noticed here so don't need checking on entry. */
+ if (&next->list == &bpf_objects_list)
+ return NULL;
+
+ return next;
+}
+
+const char *
+bpf_object__get_name(struct bpf_object *obj)
+{
+ if (!obj)
+ return NULL;
+ return obj->path;
+}
+
+struct bpf_program *
+bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
+{
+ size_t idx;
+
+ if (!obj->programs)
+ return NULL;
+ /* First handler */
+ if (prev == NULL)
+ return &obj->programs[0];
+
+ if (prev->obj != obj) {
+ pr_warning("error: program handler doesn't match object\n");
+ return NULL;
+ }
+
+ idx = (prev - obj->programs) + 1;
+ if (idx >= obj->nr_programs)
+ return NULL;
+ return &obj->programs[idx];
+}
+
+int bpf_program__set_private(struct bpf_program *prog,
+ void *priv,
+ bpf_program_clear_priv_t clear_priv)
+{
+ if (prog->priv && prog->clear_priv)
+ prog->clear_priv(prog, prog->priv);
+
+ prog->priv = priv;
+ prog->clear_priv = clear_priv;
+ return 0;
+}
+
+int bpf_program__get_private(struct bpf_program *prog, void **ppriv)
+{
+ *ppriv = prog->priv;
+ return 0;
+}
+
+const char *bpf_program__title(struct bpf_program *prog, bool dup)
+{
+ const char *title;
+
+ title = prog->section_name;
+ if (dup) {
+ title = strdup(title);
+ if (!title) {
+ pr_warning("failed to strdup program title\n");
+ return NULL;
+ }
+ }
+
+ return title;
+}
+
+int bpf_program__fd(struct bpf_program *prog)
+{
+ return prog->fd;
+}
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
new file mode 100644
index 000000000..f16170c95
--- /dev/null
+++ b/tools/lib/bpf/libbpf.h
@@ -0,0 +1,83 @@
+/*
+ * Common eBPF ELF object loading operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+#ifndef __BPF_LIBBPF_H
+#define __BPF_LIBBPF_H
+
+#include <stdio.h>
+#include <stdbool.h>
+
+/*
+ * In include/linux/compiler-gcc.h, __printf is defined. However
+ * it should be better if libbpf.h doesn't depend on Linux header file.
+ * So instead of __printf, here we use gcc attribute directly.
+ */
+typedef int (*libbpf_print_fn_t)(const char *, ...)
+ __attribute__((format(printf, 1, 2)));
+
+void libbpf_set_print(libbpf_print_fn_t warn,
+ libbpf_print_fn_t info,
+ libbpf_print_fn_t debug);
+
+/* Hide internal to user */
+struct bpf_object;
+
+struct bpf_object *bpf_object__open(const char *path);
+struct bpf_object *bpf_object__open_buffer(void *obj_buf,
+ size_t obj_buf_sz,
+ const char *name);
+void bpf_object__close(struct bpf_object *object);
+
+/* Load/unload object into/from kernel */
+int bpf_object__load(struct bpf_object *obj);
+int bpf_object__unload(struct bpf_object *obj);
+const char *bpf_object__get_name(struct bpf_object *obj);
+
+struct bpf_object *bpf_object__next(struct bpf_object *prev);
+#define bpf_object__for_each_safe(pos, tmp) \
+ for ((pos) = bpf_object__next(NULL), \
+ (tmp) = bpf_object__next(pos); \
+ (pos) != NULL; \
+ (pos) = (tmp), (tmp) = bpf_object__next(tmp))
+
+/* Accessors of bpf_program. */
+struct bpf_program;
+struct bpf_program *bpf_program__next(struct bpf_program *prog,
+ struct bpf_object *obj);
+
+#define bpf_object__for_each_program(pos, obj) \
+ for ((pos) = bpf_program__next(NULL, (obj)); \
+ (pos) != NULL; \
+ (pos) = bpf_program__next((pos), (obj)))
+
+typedef void (*bpf_program_clear_priv_t)(struct bpf_program *,
+ void *);
+
+int bpf_program__set_private(struct bpf_program *prog, void *priv,
+ bpf_program_clear_priv_t clear_priv);
+
+int bpf_program__get_private(struct bpf_program *prog,
+ void **ppriv);
+
+const char *bpf_program__title(struct bpf_program *prog, bool dup);
+
+int bpf_program__fd(struct bpf_program *prog);
+
+/*
+ * We don't need __attribute__((packed)) now since it is
+ * unnecessary for 'bpf_map_def' because they are all aligned.
+ * In addition, using it will trigger -Wpacked warning message,
+ * and will be treated as an error due to -Werror.
+ */
+struct bpf_map_def {
+ unsigned int type;
+ unsigned int key_size;
+ unsigned int value_size;
+ unsigned int max_entries;
+};
+
+#endif
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-05 18:27:04 +0000