[PATCH v11 12/39] bpf tools: Collect eBPF programs from their own sections
This patch collects all programs in an object file into an array of
'struct bpf_program' for further processing. That structure is for
representing each eBPF program. 'bpf_prog' should be a better name, but
it has been used by linux/filter.h. Although it is a kernel space name,
I still prefer to call it 'bpf_program' to prevent possible confusion.
bpf_program__new() creates a new 'struct bpf_program' object. It first
init a variable in stack using __bpf_program__new(), then if success,
enlarges obj->programs array and copy the new object in.
Signed-off-by: Wang Nan
Acked-by: Alexei Starovoitov
Cc: Brendan Gregg
Cc: Daniel Borkmann
Cc: David Ahern
Cc: He Kuang
Cc: Jiri Olsa
Cc: Kaixu Xia
Cc: Masami Hiramatsu
Cc: Namhyung Kim
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Zefan Li
Cc: pi3or...@163.com
Link:
http://lkml.kernel.org/r/1435716878-189507-13-git-send-email-wangn...@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo
---
tools/lib/bpf/libbpf.c | 117 +
1 file changed, 117 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 9b016c0..3b717de 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -78,12 +78,27 @@ void libbpf_set_print(libbpf_print_fn_t warn,
# 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 bpf_object {
char license[64];
u32 kern_version;
void *maps_buf;
size_t maps_buf_sz;
+ struct bpf_program *programs;
+ size_t nr_programs;
+
/*
* Information when doing elf related work. Only valid if fd
* is valid.
@@ -100,6 +115,84 @@ struct bpf_object {
};
#define obj_elf_valid(o) ((o)->efile.elf)
+static void bpf_program__clear(struct bpf_program *prog)
+{
+ if (!prog)
+ return;
+
+ zfree(>section_name);
+ zfree(>insns);
+ prog->insns_cnt = 0;
+ prog->idx = -1;
+}
+
+static int
+__bpf_program__new(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;
+
+ return 0;
+errout:
+ bpf_program__clear(prog);
+ return -ENOMEM;
+}
+
+static struct bpf_program *
+bpf_program__new(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__new(data, size, name, idx, );
+ if (err)
+ return NULL;
+
+ 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__clear();
+ return NULL;
+ }
+
+ obj->programs = progs;
+ obj->nr_programs = nr_progs + 1;
+ progs[nr_progs] = prog;
+ return [nr_progs];
+}
+
static struct bpf_object *bpf_object__new(const char *path,
void *obj_buf,
size_t obj_buf_sz)
@@ -342,6 +435,21 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
err = -EEXIST;
} else
obj->efile.symbols = data;
+ } else if ((sh.sh_type == SHT_PROGBITS) &&
+ (sh.sh_flags & SHF_EXECINSTR) &&
+ (data->d_size > 0)) {
+ struct bpf_program *prog;
+
+ prog = bpf_program__new(obj, data->d_buf,
+ data->d_size, name,
+ idx);
+
[PATCH v11 12/39] bpf tools: Collect eBPF programs from their own sections
This patch collects all programs in an object file into an array of
'struct bpf_program' for further processing. That structure is for
representing each eBPF program. 'bpf_prog' should be a better name, but
it has been used by linux/filter.h. Although it is a kernel space name,
I still prefer to call it 'bpf_program' to prevent possible confusion.
bpf_program__new() creates a new 'struct bpf_program' object. It first
init a variable in stack using __bpf_program__new(), then if success,
enlarges obj-programs array and copy the new object in.
Signed-off-by: Wang Nan wangn...@huawei.com
Acked-by: Alexei Starovoitov a...@plumgrid.com
Cc: Brendan Gregg brendan.d.gr...@gmail.com
Cc: Daniel Borkmann dan...@iogearbox.net
Cc: David Ahern dsah...@gmail.com
Cc: He Kuang heku...@huawei.com
Cc: Jiri Olsa jo...@kernel.org
Cc: Kaixu Xia xiaka...@huawei.com
Cc: Masami Hiramatsu masami.hiramatsu...@hitachi.com
Cc: Namhyung Kim namhy...@kernel.org
Cc: Paul Mackerras pau...@samba.org
Cc: Peter Zijlstra a.p.zijls...@chello.nl
Cc: Zefan Li lize...@huawei.com
Cc: pi3or...@163.com
Link:
http://lkml.kernel.org/r/1435716878-189507-13-git-send-email-wangn...@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo a...@redhat.com
---
tools/lib/bpf/libbpf.c | 117 +
1 file changed, 117 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 9b016c0..3b717de 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -78,12 +78,27 @@ void libbpf_set_print(libbpf_print_fn_t warn,
# 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 bpf_object {
char license[64];
u32 kern_version;
void *maps_buf;
size_t maps_buf_sz;
+ struct bpf_program *programs;
+ size_t nr_programs;
+
/*
* Information when doing elf related work. Only valid if fd
* is valid.
@@ -100,6 +115,84 @@ struct bpf_object {
};
#define obj_elf_valid(o) ((o)-efile.elf)
+static void bpf_program__clear(struct bpf_program *prog)
+{
+ if (!prog)
+ return;
+
+ zfree(prog-section_name);
+ zfree(prog-insns);
+ prog-insns_cnt = 0;
+ prog-idx = -1;
+}
+
+static int
+__bpf_program__new(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;
+
+ return 0;
+errout:
+ bpf_program__clear(prog);
+ return -ENOMEM;
+}
+
+static struct bpf_program *
+bpf_program__new(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__new(data, size, name, idx, prog);
+ if (err)
+ return NULL;
+
+ 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__clear(prog);
+ return NULL;
+ }
+
+ obj-programs = progs;
+ obj-nr_programs = nr_progs + 1;
+ progs[nr_progs] = prog;
+ return progs[nr_progs];
+}
+
static struct bpf_object *bpf_object__new(const char *path,
void *obj_buf,
size_t obj_buf_sz)
@@ -342,6 +435,21 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
err = -EEXIST;
} else
obj-efile.symbols = data;
+ } else if ((sh.sh_type == SHT_PROGBITS)
+ (sh.sh_flags SHF_EXECINSTR)
+
