From: Andrii Nakryiko <andrii@kernel.org>
To: <bpf@vger.kernel.org>, <netdev@vger.kernel.org>, <ast@fb.com>,
<daniel@iogearbox.net>
Cc: <andrii@kernel.org>, <kernel-team@fb.com>
Subject: [PATCH v6 bpf-next 11/14] libbpf: factor out low-level BPF program loading helper
Date: Thu, 3 Dec 2020 12:46:31 -0800 [thread overview]
Message-ID: <20201203204634.1325171-12-andrii@kernel.org> (raw)
In-Reply-To: <20201203204634.1325171-1-andrii@kernel.org>
Refactor low-level API for BPF program loading to not rely on public API
types. This allows painless extension without constant efforts to cleverly not
break backwards compatibility.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
tools/lib/bpf/bpf.c | 100 ++++++++++++++++++++++----------
tools/lib/bpf/libbpf.c | 34 +++++------
tools/lib/bpf/libbpf_internal.h | 29 +++++++++
3 files changed, 113 insertions(+), 50 deletions(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 4025266d0fb0..5d681ce32b37 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -215,59 +215,52 @@ alloc_zero_tailing_info(const void *orecord, __u32 cnt,
return info;
}
-int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
- char *log_buf, size_t log_buf_sz)
+int libbpf__bpf_prog_load(const struct bpf_prog_load_params *load_attr)
{
void *finfo = NULL, *linfo = NULL;
union bpf_attr attr;
- __u32 log_level;
int fd;
- if (!load_attr || !log_buf != !log_buf_sz)
+ if (!load_attr->log_buf != !load_attr->log_buf_sz)
return -EINVAL;
- log_level = load_attr->log_level;
- if (log_level > (4 | 2 | 1) || (log_level && !log_buf))
+ if (load_attr->log_level > (4 | 2 | 1) || (load_attr->log_level && !load_attr->log_buf))
return -EINVAL;
memset(&attr, 0, sizeof(attr));
attr.prog_type = load_attr->prog_type;
attr.expected_attach_type = load_attr->expected_attach_type;
- if (attr.prog_type == BPF_PROG_TYPE_STRUCT_OPS ||
- attr.prog_type == BPF_PROG_TYPE_LSM) {
- attr.attach_btf_id = load_attr->attach_btf_id;
- } else if (attr.prog_type == BPF_PROG_TYPE_TRACING ||
- attr.prog_type == BPF_PROG_TYPE_EXT) {
- attr.attach_btf_id = load_attr->attach_btf_id;
- attr.attach_prog_fd = load_attr->attach_prog_fd;
- } else {
- attr.prog_ifindex = load_attr->prog_ifindex;
- attr.kern_version = load_attr->kern_version;
- }
- attr.insn_cnt = (__u32)load_attr->insns_cnt;
+
+ attr.attach_btf_id = load_attr->attach_btf_id;
+ attr.attach_prog_fd = load_attr->attach_prog_fd;
+
+ attr.prog_ifindex = load_attr->prog_ifindex;
+ attr.kern_version = load_attr->kern_version;
+
+ attr.insn_cnt = (__u32)load_attr->insn_cnt;
attr.insns = ptr_to_u64(load_attr->insns);
attr.license = ptr_to_u64(load_attr->license);
- attr.log_level = log_level;
- if (log_level) {
- attr.log_buf = ptr_to_u64(log_buf);
- attr.log_size = log_buf_sz;
- } else {
- attr.log_buf = ptr_to_u64(NULL);
- attr.log_size = 0;
+ attr.log_level = load_attr->log_level;
+ if (attr.log_level) {
+ attr.log_buf = ptr_to_u64(load_attr->log_buf);
+ attr.log_size = load_attr->log_buf_sz;
}
attr.prog_btf_fd = load_attr->prog_btf_fd;
+ attr.prog_flags = load_attr->prog_flags;
+
attr.func_info_rec_size = load_attr->func_info_rec_size;
attr.func_info_cnt = load_attr->func_info_cnt;
attr.func_info = ptr_to_u64(load_attr->func_info);
+
attr.line_info_rec_size = load_attr->line_info_rec_size;
attr.line_info_cnt = load_attr->line_info_cnt;
attr.line_info = ptr_to_u64(load_attr->line_info);
+
if (load_attr->name)
memcpy(attr.prog_name, load_attr->name,
- min(strlen(load_attr->name), BPF_OBJ_NAME_LEN - 1));
- attr.prog_flags = load_attr->prog_flags;
+ min(strlen(load_attr->name), (size_t)BPF_OBJ_NAME_LEN - 1));
fd = sys_bpf_prog_load(&attr, sizeof(attr));
if (fd >= 0)
@@ -307,19 +300,19 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
}
fd = sys_bpf_prog_load(&attr, sizeof(attr));
-
if (fd >= 0)
goto done;
}
- if (log_level || !log_buf)
+ if (load_attr->log_level || !load_attr->log_buf)
goto done;
/* Try again with log */
- attr.log_buf = ptr_to_u64(log_buf);
- attr.log_size = log_buf_sz;
+ attr.log_buf = ptr_to_u64(load_attr->log_buf);
+ attr.log_size = load_attr->log_buf_sz;
attr.log_level = 1;
- log_buf[0] = 0;
+ load_attr->log_buf[0] = 0;
+
fd = sys_bpf_prog_load(&attr, sizeof(attr));
done:
free(finfo);
@@ -327,6 +320,49 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
return fd;
}
+int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
+ char *log_buf, size_t log_buf_sz)
+{
+ struct bpf_prog_load_params p = {};
+
+ if (!load_attr || !log_buf != !log_buf_sz)
+ return -EINVAL;
+
+ p.prog_type = load_attr->prog_type;
+ p.expected_attach_type = load_attr->expected_attach_type;
+ switch (p.prog_type) {
+ case BPF_PROG_TYPE_STRUCT_OPS:
+ case BPF_PROG_TYPE_LSM:
+ p.attach_btf_id = load_attr->attach_btf_id;
+ break;
+ case BPF_PROG_TYPE_TRACING:
+ case BPF_PROG_TYPE_EXT:
+ p.attach_btf_id = load_attr->attach_btf_id;
+ p.attach_prog_fd = load_attr->attach_prog_fd;
+ break;
+ default:
+ p.prog_ifindex = load_attr->prog_ifindex;
+ p.kern_version = load_attr->kern_version;
+ }
+ p.insn_cnt = load_attr->insns_cnt;
+ p.insns = load_attr->insns;
+ p.license = load_attr->license;
+ p.log_level = load_attr->log_level;
+ p.log_buf = log_buf;
+ p.log_buf_sz = log_buf_sz;
+ p.prog_btf_fd = load_attr->prog_btf_fd;
+ p.func_info_rec_size = load_attr->func_info_rec_size;
+ p.func_info_cnt = load_attr->func_info_cnt;
+ p.func_info = load_attr->func_info;
+ p.line_info_rec_size = load_attr->line_info_rec_size;
+ p.line_info_cnt = load_attr->line_info_cnt;
+ p.line_info = load_attr->line_info;
+ p.name = load_attr->name;
+ p.prog_flags = load_attr->prog_flags;
+
+ return libbpf__bpf_prog_load(&p);
+}
+
int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, const char *license,
__u32 kern_version, char *log_buf,
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index ca20e493726d..103d66e27406 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -6809,7 +6809,7 @@ static int
load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
char *license, __u32 kern_version, int *pfd)
{
- struct bpf_load_program_attr load_attr;
+ struct bpf_prog_load_params load_attr = {};
char *cp, errmsg[STRERR_BUFSIZE];
size_t log_buf_size = 0;
char *log_buf = NULL;
@@ -6828,7 +6828,6 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
if (!insns || !insns_cnt)
return -EINVAL;
- memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
load_attr.prog_type = prog->type;
/* old kernels might not support specifying expected_attach_type */
if (!kernel_supports(FEAT_EXP_ATTACH_TYPE) && prog->sec_def &&
@@ -6839,19 +6838,14 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
if (kernel_supports(FEAT_PROG_NAME))
load_attr.name = prog->name;
load_attr.insns = insns;
- load_attr.insns_cnt = insns_cnt;
+ load_attr.insn_cnt = insns_cnt;
load_attr.license = license;
- if (prog->type == BPF_PROG_TYPE_STRUCT_OPS ||
- prog->type == BPF_PROG_TYPE_LSM) {
- load_attr.attach_btf_id = prog->attach_btf_id;
- } else if (prog->type == BPF_PROG_TYPE_TRACING ||
- prog->type == BPF_PROG_TYPE_EXT) {
- load_attr.attach_prog_fd = prog->attach_prog_fd;
- load_attr.attach_btf_id = prog->attach_btf_id;
- } else {
- load_attr.kern_version = kern_version;
- load_attr.prog_ifindex = prog->prog_ifindex;
- }
+ load_attr.attach_btf_id = prog->attach_btf_id;
+ load_attr.attach_prog_fd = prog->attach_prog_fd;
+ load_attr.attach_btf_id = prog->attach_btf_id;
+ load_attr.kern_version = kern_version;
+ load_attr.prog_ifindex = prog->prog_ifindex;
+
/* specify func_info/line_info only if kernel supports them */
btf_fd = bpf_object__btf_fd(prog->obj);
if (btf_fd >= 0 && kernel_supports(FEAT_BTF_FUNC)) {
@@ -6875,7 +6869,9 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
*log_buf = 0;
}
- ret = bpf_load_program_xattr(&load_attr, log_buf, log_buf_size);
+ load_attr.log_buf = log_buf;
+ load_attr.log_buf_sz = log_buf_size;
+ ret = libbpf__bpf_prog_load(&load_attr);
if (ret >= 0) {
if (log_buf && load_attr.log_level)
@@ -6916,9 +6912,9 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
pr_warn("-- BEGIN DUMP LOG ---\n");
pr_warn("\n%s\n", log_buf);
pr_warn("-- END LOG --\n");
- } else if (load_attr.insns_cnt >= BPF_MAXINSNS) {
+ } else if (load_attr.insn_cnt >= BPF_MAXINSNS) {
pr_warn("Program too large (%zu insns), at most %d insns\n",
- load_attr.insns_cnt, BPF_MAXINSNS);
+ load_attr.insn_cnt, BPF_MAXINSNS);
ret = -LIBBPF_ERRNO__PROG2BIG;
} else if (load_attr.prog_type != BPF_PROG_TYPE_KPROBE) {
/* Wrong program type? */
@@ -6926,7 +6922,9 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt,
load_attr.prog_type = BPF_PROG_TYPE_KPROBE;
load_attr.expected_attach_type = 0;
- fd = bpf_load_program_xattr(&load_attr, NULL, 0);
+ load_attr.log_buf = NULL;
+ load_attr.log_buf_sz = 0;
+ fd = libbpf__bpf_prog_load(&load_attr);
if (fd >= 0) {
close(fd);
ret = -LIBBPF_ERRNO__PROGTYPE;
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
index e569ae63808e..681073a67ae3 100644
--- a/tools/lib/bpf/libbpf_internal.h
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -151,6 +151,35 @@ int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz);
int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
const char *str_sec, size_t str_len);
+struct bpf_prog_load_params {
+ enum bpf_prog_type prog_type;
+ enum bpf_attach_type expected_attach_type;
+ const char *name;
+ const struct bpf_insn *insns;
+ size_t insn_cnt;
+ const char *license;
+ __u32 kern_version;
+ __u32 attach_prog_fd;
+ __u32 attach_btf_id;
+ __u32 prog_ifindex;
+ __u32 prog_btf_fd;
+ __u32 prog_flags;
+
+ __u32 func_info_rec_size;
+ const void *func_info;
+ __u32 func_info_cnt;
+
+ __u32 line_info_rec_size;
+ const void *line_info;
+ __u32 line_info_cnt;
+
+ __u32 log_level;
+ char *log_buf;
+ size_t log_buf_sz;
+};
+
+int libbpf__bpf_prog_load(const struct bpf_prog_load_params *load_attr);
+
int bpf_object__section_size(const struct bpf_object *obj, const char *name,
__u32 *size);
int bpf_object__variable_offset(const struct bpf_object *obj, const char *name,
--
2.24.1
next prev parent reply other threads:[~2020-12-03 20:49 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-03 20:46 [PATCH v6 bpf-next 00/14] Support BTF-powered BPF tracing programs for kernel modules Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 01/14] bpf: fix bpf_put_raw_tracepoint()'s use of __module_address() Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 02/14] bpf: keep module's btf_data_size intact after load Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 03/14] libbpf: add internal helper to load BTF data by FD Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 04/14] libbpf: refactor CO-RE relocs to not assume a single BTF object Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 05/14] libbpf: add kernel module BTF support for CO-RE relocations Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 06/14] selftests/bpf: add bpf_testmod kernel module for testing Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 07/14] selftests/bpf: add support for marking sub-tests as skipped Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 08/14] selftests/bpf: add CO-RE relocs selftest relying on kernel module BTF Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 09/14] bpf: remove hard-coded btf_vmlinux assumption from BPF verifier Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 10/14] bpf: allow to specify kernel module BTFs when attaching BPF programs Andrii Nakryiko
2020-12-04 1:53 ` Alexei Starovoitov
2020-12-04 19:31 ` Andrii Nakryiko
2020-12-03 20:46 ` Andrii Nakryiko [this message]
2020-12-03 20:46 ` [PATCH v6 bpf-next 12/14] libbpf: support attachment of BPF tracing programs to kernel modules Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 13/14] selftests/bpf: add tp_btf CO-RE reloc test for modules Andrii Nakryiko
2020-12-03 20:46 ` [PATCH v6 bpf-next 14/14] selftests/bpf: add fentry/fexit/fmod_ret selftest for kernel module Andrii Nakryiko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201203204634.1325171-12-andrii@kernel.org \
--to=andrii@kernel.org \
--cc=ast@fb.com \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=kernel-team@fb.com \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.