sync: latest libbpf changes from kernel

Syncing latest libbpf commits from kernel repository.
Baseline bpf-next commit:   b615e5a1e067dcb327482d1af7463268b89b1629
Checkpoint bpf-next commit: e7096c131e5161fa3b8e52a650d7719d2857adfd
Baseline bpf commit:        34e59836565e36fade1464e054a3551c1a0364be
Checkpoint bpf commit:      e42617b825f8073569da76dc4510bfa019b1c35a

Alexei Starovoitov (2):
  libbpf: Fix sym->st_value print on 32-bit arches
  selftests/bpf: Add test for BPF trampoline

Andrii Nakryiko (1):
  libbpf: Fix global variable relocation

Martin KaFai Lau (1):
  bpf: Introduce BPF_TRACE_x helper for the tracing tests

 src/libbpf.c | 45 ++++++++++++++++++++-------------------------
 1 file changed, 20 insertions(+), 25 deletions(-)

--
2.17.1

.lgtm.yml

@@ -0,0 +1,14 @@
+# vi: set ts=2 sw=2:
+extraction:
+  cpp:
+    prepare:
+      packages:
+        - libelf-dev
+        - pkg-config
+    after_prepare:
+      # As the buildsystem detection by LGTM is performed _only_ during the
+      # 'configure' phase, we need to trick LGTM we use a supported build
+      # system (configure, meson, cmake, etc.). This way LGTM correctly detects
+      # that our sources are in the src/ subfolder.
+      - touch src/configure
+      - chmod +x src/configure

.travis.yml

@@ -1,14 +1,24 @@
 sudo: required
-dist: xenial
+dist: bionic
 services:
     - docker
 
 env:
     global:
-        - AUTHOR_EMAIL="$(git log -1 $TRAVIS_COMMIT --pretty=\"%aE\")"
+        - AUTHOR_EMAIL="$(git log -1 --pretty=\"%aE\")"
         - CI_MANAGERS="$TRAVIS_BUILD_DIR/travis-ci/managers"
         - REPO_ROOT="$TRAVIS_BUILD_DIR"
 
+stages:
+    # Run Coverity periodically instead of for each PR for following reasons:
+    # 1) Coverity jobs are heavily rate-limited
+    # 2) Due to security restrictions of encrypted environment variables
+    #    in Travis CI, pull requests made from forks can't access encrypted
+    #    env variables, making Coverity unusable
+    #    See: https://docs.travis-ci.com/user/pull-requests#pull-requests-and-security-restrictions
+    - name: Coverity
+      if: type = cron
+
 jobs:
     include:
         - stage: Build & test
@@ -23,9 +33,7 @@ jobs:
           install:
               - $CI_MANAGERS/debian.sh SETUP
           script:
-              - set -e
-              - $CI_MANAGERS/debian.sh RUN
-              - set +e
+              - $CI_MANAGERS/debian.sh RUN || travis_terminate
           after_script:
               - $CI_MANAGERS/debian.sh CLEANUP
 
@@ -40,9 +48,7 @@ jobs:
           install:
               - $CI_MANAGERS/debian.sh SETUP
           script:
-              - set -e
-              - $CI_MANAGERS/debian.sh RUN_ASAN
-              - set +e
+              - $CI_MANAGERS/debian.sh RUN_ASAN || travis_terminate
           after_script:
               - $CI_MANAGERS/debian.sh CLEANUP
 
@@ -57,9 +63,7 @@ jobs:
           install:
               - $CI_MANAGERS/debian.sh SETUP
           script:
-              - set -e
-              - $CI_MANAGERS/debian.sh RUN_CLANG
-              - set +e
+              - $CI_MANAGERS/debian.sh RUN_CLANG || travis_terminate
           after_script:
               - $CI_MANAGERS/debian.sh CLEANUP
 
@@ -74,9 +78,7 @@ jobs:
           install:
               - $CI_MANAGERS/debian.sh SETUP
           script:
-              - set -e
-              - $CI_MANAGERS/debian.sh RUN_CLANG_ASAN
-              - set +e
+              - $CI_MANAGERS/debian.sh RUN_CLANG_ASAN || travis_terminate
           after_script:
               - $CI_MANAGERS/debian.sh CLEANUP
 
@@ -91,9 +93,7 @@ jobs:
           install:
               - $CI_MANAGERS/debian.sh SETUP
           script:
-              - set -e
-              - $CI_MANAGERS/debian.sh RUN_GCC8
-              - set +e
+              - $CI_MANAGERS/debian.sh RUN_GCC8 || travis_terminate
           after_script:
               - $CI_MANAGERS/debian.sh CLEANUP
 
@@ -108,15 +108,44 @@ jobs:
           install:
               - $CI_MANAGERS/debian.sh SETUP
           script:
-              - set -e
-              - $CI_MANAGERS/debian.sh RUN_GCC8_ASAN
-              - set +e
+              - $CI_MANAGERS/debian.sh RUN_GCC8_ASAN || travis_terminate
           after_script:
               - $CI_MANAGERS/debian.sh CLEANUP
 
-        - name: Ubuntu Xenial
+        - name: Ubuntu Bionic
           language: bash
           script:
-              - set -e
-              - sudo $CI_MANAGERS/xenial.sh
-              - set +e
+              - sudo $CI_MANAGERS/ubuntu.sh || travis_terminate
+
+        - name: Ubuntu Bionic (arm)
+          arch: arm64
+          language: bash
+          script:
+              - sudo $CI_MANAGERS/ubuntu.sh || travis_terminate
+
+        - name: Ubuntu Bionic (s390x)
+          arch: s390x
+          language: bash
+          script:
+              - sudo $CI_MANAGERS/ubuntu.sh || travis_terminate
+
+        - stage: Coverity
+          language: bash
+          env:
+              # Coverity configuration
+              # COVERITY_SCAN_TOKEN=xxx
+              # Encrypted using `travis encrypt --repo libbpf/libbpf COVERITY_SCAN_TOKEN=xxx`
+              - secure: "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"
+              - COVERITY_SCAN_PROJECT_NAME="libbpf"
+              - COVERITY_SCAN_NOTIFICATION_EMAIL="${AUTHOR_EMAIL}"
+              - COVERITY_SCAN_BRANCH_PATTERN="$TRAVIS_BRANCH"
+              # Note: `make -C src/` as a BUILD_COMMAND will not work here
+              - COVERITY_SCAN_BUILD_COMMAND_PREPEND="cd src/"
+              - COVERITY_SCAN_BUILD_COMMAND="make"
+          install:
+              - sudo echo 'deb-src http://archive.ubuntu.com/ubuntu/ bionic main restricted universe multiverse' >>/etc/apt/sources.list
+              - sudo apt-get update
+              - sudo apt-get -y build-dep libelf-dev
+              - sudo apt-get install -y libelf-dev pkg-config
+          script:
+              - scripts/coverity.sh || travis_terminate

BPF-CHECKPOINT-COMMIT

@@ -0,0 +1 @@
+e42617b825f8073569da76dc4510bfa019b1c35a

CHECKPOINT-COMMIT

@@ -1 +1 @@
-66b5f1c439843bcbab01cc7f3854ae2742f3d1e3
+e7096c131e5161fa3b8e52a650d7719d2857adfd

LICENSE

@@ -0,0 +1 @@
+LGPL-2.1 OR BSD-2-Clause

LICENSE.BSD-2-Clause

@@ -0,0 +1,32 @@
+Valid-License-Identifier: BSD-2-Clause
+SPDX-URL: https://spdx.org/licenses/BSD-2-Clause.html
+Usage-Guide:
+  To use the BSD 2-clause "Simplified" License put the following SPDX
+  tag/value pair into a comment according to the placement guidelines in
+  the licensing rules documentation:
+    SPDX-License-Identifier: BSD-2-Clause
+License-Text:
+
+Copyright (c) <year> <owner> . All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.

LICENSE.LPGL-2.1

@@ -0,0 +1,503 @@
+Valid-License-Identifier: LGPL-2.1
+Valid-License-Identifier: LGPL-2.1+
+SPDX-URL: https://spdx.org/licenses/LGPL-2.1.html
+Usage-Guide:
+  To use this license in source code, put one of the following SPDX
+  tag/value pairs into a comment according to the placement
+  guidelines in the licensing rules documentation.
+  For 'GNU Lesser General Public License (LGPL) version 2.1 only' use:
+    SPDX-License-Identifier: LGPL-2.1
+  For 'GNU Lesser General Public License (LGPL) version 2.1 or any later
+  version' use:
+    SPDX-License-Identifier: LGPL-2.1+
+License-Text:
+
+GNU LESSER GENERAL PUBLIC LICENSE
+Version 2.1, February 1999
+
+Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL. It also counts as
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+
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+
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+
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+
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+possible use to the public, we recommend making it free software that
+everyone can redistribute and change. You can do so by permitting
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+
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+
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+the library `Frob' (a library for tweaking knobs) written
+by James Random Hacker.
+
+signature of Ty Coon, 1 April 1990
+Ty Coon, President of Vice
+That's all there is to it!

README.md

@@ -16,7 +16,10 @@ Other header files at this repo (`include/linux/*.h`) are reduced versions of
 their counterpart files at bpf-next's `tools/include/linux/*.h` to make compilation
 successful.
 
-Build [![Build Status](https://travis-ci.org/libbpf/libbpf.svg?branch=master)](https://travis-ci.org/libbpf/libbpf)
+Build
+[![Build Status](https://travis-ci.org/libbpf/libbpf.svg?branch=master)](https://travis-ci.org/libbpf/libbpf)
+[![Total alerts](https://img.shields.io/lgtm/alerts/g/libbpf/libbpf.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/libbpf/libbpf/alerts/)
+[![Coverity](https://img.shields.io/coverity/scan/18195.svg)](https://scan.coverity.com/projects/libbpf)
 =====
 libelf is an internal dependency of libbpf and thus it is required to link
 against and must be installed on the system for applications to work.
@@ -48,23 +51,10 @@ $ cd src
 $ PKG_CONFIG_PATH=/build/root/lib64/pkgconfig DESTDIR=/build/root make install
 ```
 
-To integrate libbpf into a project which uses Meson building system define
-`[wrap-git]` file in `subprojects` folder.
-To add libbpf dependency to the parent parent project, e.g. for
-libbpf_static_dep:
-```
-libbpf_obj = subproject('libbpf', required : true)
-libbpf_static_dep = libbpf_proj.get_variable('libbpf_static_dep')
-```
+License
+=====
 
-To validate changes to meson.build
-```bash
-$ python3 meson.py build
-$ ninja -C build/
-```
+This work is dual-licensed under BSD 2-clause license and GNU LGPL v2.1 license.
+You can choose between one of them if you use this work.
 
-To install headers, libs and pkgconfig
-```bash
-$ cd build
-$ ninja install
-```
+`SPDX-License-Identifier: BSD-2-Clause OR LGPL-2.1`

include/linux/filter.h

@@ -96,7 +96,7 @@
 			      MAP_FD, 0)
 
 #define BPF_LD_MAP_VALUE(DST, MAP_FD, VALUE_OFF)		\
-	BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_FD, 0, 0,	\
+	BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_VALUE, 0, 0,	\
 			      MAP_FD, VALUE_OFF)
 
 #define BPF_JMP_IMM(OP, DST, IMM, OFF)				\
@@ -107,5 +107,12 @@
 		.off  = OFF,					\
 		.imm  = IMM })
 
+#define BPF_JMP32_IMM(OP, DST, IMM, OFF)			\
+	((struct bpf_insn) {					\
+		.code = BPF_JMP32 | BPF_OP(OP) | BPF_K,		\
+		.dst_reg = DST,					\
+		.src_reg = 0,					\
+		.off  = OFF,					\
+		.imm  = IMM })
 
 #endif

include/uapi/linux/bpf.h

@@ -106,6 +106,7 @@ enum bpf_cmd {
 	BPF_TASK_FD_QUERY,
 	BPF_MAP_LOOKUP_AND_DELETE_ELEM,
 	BPF_MAP_FREEZE,
+	BPF_BTF_GET_NEXT_ID,
 };
 
 enum bpf_map_type {
@@ -134,6 +135,7 @@ enum bpf_map_type {
 	BPF_MAP_TYPE_QUEUE,
 	BPF_MAP_TYPE_STACK,
 	BPF_MAP_TYPE_SK_STORAGE,
+	BPF_MAP_TYPE_DEVMAP_HASH,
 };
 
 /* Note that tracing related programs such as
@@ -171,6 +173,7 @@ enum bpf_prog_type {
 	BPF_PROG_TYPE_CGROUP_SYSCTL,
 	BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
 	BPF_PROG_TYPE_CGROUP_SOCKOPT,
+	BPF_PROG_TYPE_TRACING,
 };
 
 enum bpf_attach_type {
@@ -197,6 +200,9 @@ enum bpf_attach_type {
 	BPF_CGROUP_UDP6_RECVMSG,
 	BPF_CGROUP_GETSOCKOPT,
 	BPF_CGROUP_SETSOCKOPT,
+	BPF_TRACE_RAW_TP,
+	BPF_TRACE_FENTRY,
+	BPF_TRACE_FEXIT,
 	__MAX_BPF_ATTACH_TYPE
 };
 
@@ -283,6 +289,9 @@ enum bpf_attach_type {
  */
 #define BPF_F_TEST_RND_HI32	(1U << 2)
 
+/* The verifier internal test flag. Behavior is undefined */
+#define BPF_F_TEST_STATE_FREQ	(1U << 3)
+
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
  * two extensions:
  *
@@ -336,6 +345,12 @@ enum bpf_attach_type {
 #define BPF_F_RDONLY_PROG	(1U << 7)
 #define BPF_F_WRONLY_PROG	(1U << 8)
 
+/* Clone map from listener for newly accepted socket */
+#define BPF_F_CLONE		(1U << 9)
+
+/* Enable memory-mapping BPF map */
+#define BPF_F_MMAPABLE		(1U << 10)
+
 /* flags for BPF_PROG_QUERY */
 #define BPF_F_QUERY_EFFECTIVE	(1U << 0)
 
@@ -412,6 +427,8 @@ union bpf_attr {
 		__u32		line_info_rec_size;	/* userspace bpf_line_info size */
 		__aligned_u64	line_info;	/* line info */
 		__u32		line_info_cnt;	/* number of bpf_line_info records */
+		__u32		attach_btf_id;	/* in-kernel BTF type id to attach to */
+		__u32		attach_prog_fd; /* 0 to attach to vmlinux */
 	};
 
 	struct { /* anonymous struct used by BPF_OBJ_* commands */
@@ -552,10 +569,13 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_probe_read(void *dst, u32 size, const void *src)
+ * int bpf_probe_read(void *dst, u32 size, const void *unsafe_ptr)
  * 	Description
  * 		For tracing programs, safely attempt to read *size* bytes from
- * 		address *src* and store the data in *dst*.
+ * 		kernel space address *unsafe_ptr* and store the data in *dst*.
+ *
+ * 		Generally, use bpf_probe_read_user() or bpf_probe_read_kernel()
+ * 		instead.
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
@@ -575,6 +595,8 @@ union bpf_attr {
  * 		limited to five).
  *
  * 		Each time the helper is called, it appends a line to the trace.
+ * 		Lines are discarded while *\/sys/kernel/debug/tracing/trace* is
+ * 		open, use *\/sys/kernel/debug/tracing/trace_pipe* to avoid this.
  * 		The format of the trace is customizable, and the exact output
  * 		one will get depends on the options set in
  * 		*\/sys/kernel/debug/tracing/trace_options* (see also the
@@ -784,7 +806,7 @@ union bpf_attr {
  * 		A 64-bit integer containing the current GID and UID, and
  * 		created as such: *current_gid* **<< 32 \|** *current_uid*.
  *
- * int bpf_get_current_comm(char *buf, u32 size_of_buf)
+ * int bpf_get_current_comm(void *buf, u32 size_of_buf)
  * 	Description
  * 		Copy the **comm** attribute of the current task into *buf* of
  * 		*size_of_buf*. The **comm** attribute contains the name of
@@ -1013,7 +1035,7 @@ union bpf_attr {
  * 		The realm of the route for the packet associated to *skb*, or 0
  * 		if none was found.
  *
- * int bpf_perf_event_output(struct pt_reg *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
+ * int bpf_perf_event_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
  * 	Description
  * 		Write raw *data* blob into a special BPF perf event held by
  * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
@@ -1058,7 +1080,7 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
+ * int bpf_skb_load_bytes(const void *skb, u32 offset, void *to, u32 len)
  * 	Description
  * 		This helper was provided as an easy way to load data from a
  * 		packet. It can be used to load *len* bytes from *offset* from
@@ -1075,7 +1097,7 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_get_stackid(struct pt_reg *ctx, struct bpf_map *map, u64 flags)
+ * int bpf_get_stackid(void *ctx, struct bpf_map *map, u64 flags)
  * 	Description
  * 		Walk a user or a kernel stack and return its id. To achieve
  * 		this, the helper needs *ctx*, which is a pointer to the context
@@ -1144,7 +1166,7 @@ union bpf_attr {
  * 		The checksum result, or a negative error code in case of
  * 		failure.
  *
- * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
  * 	Description
  * 		Retrieve tunnel options metadata for the packet associated to
  * 		*skb*, and store the raw tunnel option data to the buffer *opt*
@@ -1162,7 +1184,7 @@ union bpf_attr {
  * 	Return
  * 		The size of the option data retrieved.
  *
- * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, void *opt, u32 size)
  * 	Description
  * 		Set tunnel options metadata for the packet associated to *skb*
  * 		to the option data contained in the raw buffer *opt* of *size*.
@@ -1415,45 +1437,14 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
+ * int bpf_probe_read_str(void *dst, u32 size, const void *unsafe_ptr)
  * 	Description
- * 		Copy a NUL terminated string from an unsafe address
- * 		*unsafe_ptr* to *dst*. The *size* should include the
- * 		terminating NUL byte. In case the string length is smaller than
- * 		*size*, the target is not padded with further NUL bytes. If the
- * 		string length is larger than *size*, just *size*-1 bytes are
- * 		copied and the last byte is set to NUL.
+ * 		Copy a NUL terminated string from an unsafe kernel address
+ * 		*unsafe_ptr* to *dst*. See bpf_probe_read_kernel_str() for
+ * 		more details.
  *
- * 		On success, the length of the copied string is returned. This
- * 		makes this helper useful in tracing programs for reading
- * 		strings, and more importantly to get its length at runtime. See
- * 		the following snippet:
- *
- * 		::
- *
- * 			SEC("kprobe/sys_open")
- * 			void bpf_sys_open(struct pt_regs *ctx)
- * 			{
- * 			        char buf[PATHLEN]; // PATHLEN is defined to 256
- * 			        int res = bpf_probe_read_str(buf, sizeof(buf),
- * 				                             ctx->di);
- *
- * 				// Consume buf, for example push it to
- * 				// userspace via bpf_perf_event_output(); we
- * 				// can use res (the string length) as event
- * 				// size, after checking its boundaries.
- * 			}
- *
- * 		In comparison, using **bpf_probe_read()** helper here instead
- * 		to read the string would require to estimate the length at
- * 		compile time, and would often result in copying more memory
- * 		than necessary.
- *
- * 		Another useful use case is when parsing individual process
- * 		arguments or individual environment variables navigating
- * 		*current*\ **->mm->arg_start** and *current*\
- * 		**->mm->env_start**: using this helper and the return value,
- * 		one can quickly iterate at the right offset of the memory area.
+ * 		Generally, use bpf_probe_read_user_str() or bpf_probe_read_kernel_str()
+ * 		instead.
  * 	Return
  * 		On success, the strictly positive length of the string,
  * 		including the trailing NUL character. On error, a negative
@@ -1466,8 +1457,8 @@ union bpf_attr {
  * 		If no cookie has been set yet, generate a new cookie. Once
  * 		generated, the socket cookie remains stable for the life of the
  * 		socket. This helper can be useful for monitoring per socket
- * 		networking traffic statistics as it provides a unique socket
- * 		identifier per namespace.
+ * 		networking traffic statistics as it provides a global socket
+ * 		identifier that can be assumed unique.
  * 	Return
  * 		A 8-byte long non-decreasing number on success, or 0 if the
  * 		socket field is missing inside *skb*.
@@ -1501,7 +1492,7 @@ union bpf_attr {
  * 	Return
  * 		0
  *
- * int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
+ * int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, void *optval, int optlen)
  * 	Description
  * 		Emulate a call to **setsockopt()** on the socket associated to
  * 		*bpf_socket*, which must be a full socket. The *level* at
@@ -1571,8 +1562,11 @@ union bpf_attr {
  * 		but this is only implemented for native XDP (with driver
  * 		support) as of this writing).
  *
- * 		All values for *flags* are reserved for future usage, and must
- * 		be left at zero.
+ * 		The lower two bits of *flags* are used as the return code if
+ * 		the map lookup fails. This is so that the return value can be
+ * 		one of the XDP program return codes up to XDP_TX, as chosen by
+ * 		the caller. Any higher bits in the *flags* argument must be
+ * 		unset.
  *
  * 		When used to redirect packets to net devices, this helper
  * 		provides a high performance increase over **bpf_redirect**\ ().
@@ -1582,7 +1576,7 @@ union bpf_attr {
  * 	Return
  * 		**XDP_REDIRECT** on success, or **XDP_ABORTED** on error.
  *
- * int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * int bpf_sk_redirect_map(struct sk_buff *skb, struct bpf_map *map, u32 key, u64 flags)
  * 	Description
  * 		Redirect the packet to the socket referenced by *map* (of type
  * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
@@ -1702,7 +1696,7 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
+ * int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, void *optval, int optlen)
  * 	Description
  * 		Emulate a call to **getsockopt()** on the socket associated to
  * 		*bpf_socket*, which must be a full socket. The *level* at
@@ -1721,7 +1715,7 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_override_return(struct pt_reg *regs, u64 rc)
+ * int bpf_override_return(struct pt_regs *regs, u64 rc)
  * 	Description
  * 		Used for error injection, this helper uses kprobes to override
  * 		the return value of the probed function, and to set it to *rc*.
@@ -1934,7 +1928,7 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_get_stack(struct pt_regs *regs, void *buf, u32 size, u64 flags)
+ * int bpf_get_stack(void *ctx, void *buf, u32 size, u64 flags)
  * 	Description
  * 		Return a user or a kernel stack in bpf program provided buffer.
  * 		To achieve this, the helper needs *ctx*, which is a pointer
@@ -1967,7 +1961,7 @@ union bpf_attr {
  * 		A non-negative value equal to or less than *size* on success,
  * 		or a negative error in case of failure.
  *
- * int bpf_skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header)
+ * int bpf_skb_load_bytes_relative(const void *skb, u32 offset, void *to, u32 len, u32 start_header)
  * 	Description
  * 		This helper is similar to **bpf_skb_load_bytes**\ () in that
  * 		it provides an easy way to load *len* bytes from *offset*
@@ -2020,7 +2014,7 @@ union bpf_attr {
  *		* > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the
  *		  packet is not forwarded or needs assist from full stack
  *
- * int bpf_sock_hash_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags)
+ * int bpf_sock_hash_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags)
  *	Description
  *		Add an entry to, or update a sockhash *map* referencing sockets.
  *		The *skops* is used as a new value for the entry associated to
@@ -2379,7 +2373,7 @@ union bpf_attr {
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
- * int bpf_msg_push_data(struct sk_buff *skb, u32 start, u32 len, u64 flags)
+ * int bpf_msg_push_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
  *	Description
  *		For socket policies, insert *len* bytes into *msg* at offset
  *		*start*.
@@ -2395,9 +2389,9 @@ union bpf_attr {
  *	Return
  *		0 on success, or a negative error in case of failure.
  *
- * int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags)
+ * int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
  *	Description
- *		Will remove *pop* bytes from a *msg* starting at byte *start*.
+ *		Will remove *len* bytes from a *msg* starting at byte *start*.
  *		This may result in **ENOMEM** errors under certain situations if
  *		an allocation and copy are required due to a full ring buffer.
  *		However, the helper will try to avoid doing the allocation
@@ -2492,7 +2486,7 @@ union bpf_attr {
  *		A **struct bpf_tcp_sock** pointer on success, or **NULL** in
  *		case of failure.
  *
- * int bpf_skb_ecn_set_ce(struct sk_buf *skb)
+ * int bpf_skb_ecn_set_ce(struct sk_buff *skb)
  *	Description
  *		Set ECN (Explicit Congestion Notification) field of IP header
  *		to **CE** (Congestion Encountered) if current value is **ECT**
@@ -2710,6 +2704,123 @@ union bpf_attr {
  *		**-EPERM** if no permission to send the *sig*.
  *
  *		**-EAGAIN** if bpf program can try again.
+ *
+ * s64 bpf_tcp_gen_syncookie(struct bpf_sock *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len)
+ *	Description
+ *		Try to issue a SYN cookie for the packet with corresponding
+ *		IP/TCP headers, *iph* and *th*, on the listening socket in *sk*.
+ *
+ *		*iph* points to the start of the IPv4 or IPv6 header, while
+ *		*iph_len* contains **sizeof**\ (**struct iphdr**) or
+ *		**sizeof**\ (**struct ip6hdr**).
+ *
+ *		*th* points to the start of the TCP header, while *th_len*
+ *		contains the length of the TCP header.
+ *
+ *	Return
+ *		On success, lower 32 bits hold the generated SYN cookie in
+ *		followed by 16 bits which hold the MSS value for that cookie,
+ *		and the top 16 bits are unused.
+ *
+ *		On failure, the returned value is one of the following:
+ *
+ *		**-EINVAL** SYN cookie cannot be issued due to error
+ *
+ *		**-ENOENT** SYN cookie should not be issued (no SYN flood)
+ *
+ *		**-EOPNOTSUPP** kernel configuration does not enable SYN cookies
+ *
+ *		**-EPROTONOSUPPORT** IP packet version is not 4 or 6
+ *
+ * int bpf_skb_output(void *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
+ * 	Description
+ * 		Write raw *data* blob into a special BPF perf event held by
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
+ * 		event must have the following attributes: **PERF_SAMPLE_RAW**
+ * 		as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
+ * 		**PERF_COUNT_SW_BPF_OUTPUT** as **config**.
+ *
+ * 		The *flags* are used to indicate the index in *map* for which
+ * 		the value must be put, masked with **BPF_F_INDEX_MASK**.
+ * 		Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
+ * 		to indicate that the index of the current CPU core should be
+ * 		used.
+ *
+ * 		The value to write, of *size*, is passed through eBPF stack and
+ * 		pointed by *data*.
+ *
+ * 		*ctx* is a pointer to in-kernel struct sk_buff.
+ *
+ * 		This helper is similar to **bpf_perf_event_output**\ () but
+ * 		restricted to raw_tracepoint bpf programs.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_probe_read_user(void *dst, u32 size, const void *unsafe_ptr)
+ * 	Description
+ * 		Safely attempt to read *size* bytes from user space address
+ * 		*unsafe_ptr* and store the data in *dst*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr)
+ * 	Description
+ * 		Safely attempt to read *size* bytes from kernel space address
+ * 		*unsafe_ptr* and store the data in *dst*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_probe_read_user_str(void *dst, u32 size, const void *unsafe_ptr)
+ * 	Description
+ * 		Copy a NUL terminated string from an unsafe user address
+ * 		*unsafe_ptr* to *dst*. The *size* should include the
+ * 		terminating NUL byte. In case the string length is smaller than
+ * 		*size*, the target is not padded with further NUL bytes. If the
+ * 		string length is larger than *size*, just *size*-1 bytes are
+ * 		copied and the last byte is set to NUL.
+ *
+ * 		On success, the length of the copied string is returned. This
+ * 		makes this helper useful in tracing programs for reading
+ * 		strings, and more importantly to get its length at runtime. See
+ * 		the following snippet:
+ *
+ * 		::
+ *
+ * 			SEC("kprobe/sys_open")
+ * 			void bpf_sys_open(struct pt_regs *ctx)
+ * 			{
+ * 			        char buf[PATHLEN]; // PATHLEN is defined to 256
+ * 			        int res = bpf_probe_read_user_str(buf, sizeof(buf),
+ * 				                                  ctx->di);
+ *
+ * 				// Consume buf, for example push it to
+ * 				// userspace via bpf_perf_event_output(); we
+ * 				// can use res (the string length) as event
+ * 				// size, after checking its boundaries.
+ * 			}
+ *
+ * 		In comparison, using **bpf_probe_read_user()** helper here
+ * 		instead to read the string would require to estimate the length
+ * 		at compile time, and would often result in copying more memory
+ * 		than necessary.
+ *
+ * 		Another useful use case is when parsing individual process
+ * 		arguments or individual environment variables navigating
+ * 		*current*\ **->mm->arg_start** and *current*\
+ * 		**->mm->env_start**: using this helper and the return value,
+ * 		one can quickly iterate at the right offset of the memory area.
+ * 	Return
+ * 		On success, the strictly positive length of the string,
+ * 		including the trailing NUL character. On error, a negative
+ * 		value.
+ *
+ * int bpf_probe_read_kernel_str(void *dst, u32 size, const void *unsafe_ptr)
+ * 	Description
+ * 		Copy a NUL terminated string from an unsafe kernel address *unsafe_ptr*
+ * 		to *dst*. Same semantics as with bpf_probe_read_user_str() apply.
+ * 	Return
+ * 		On success, the strictly positive length of the string,	including
+ * 		the trailing NUL character. On error, a negative value.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2821,7 +2932,13 @@ union bpf_attr {
 	FN(strtoul),			\
 	FN(sk_storage_get),		\
 	FN(sk_storage_delete),		\
-	FN(send_signal),
+	FN(send_signal),		\
+	FN(tcp_gen_syncookie),		\
+	FN(skb_output),			\
+	FN(probe_read_user),		\
+	FN(probe_read_kernel),		\
+	FN(probe_read_user_str),	\
+	FN(probe_read_kernel_str),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -3504,6 +3621,10 @@ enum bpf_task_fd_type {
 	BPF_FD_TYPE_URETPROBE,		/* filename + offset */
 };
 
+#define BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG		(1U << 0)
+#define BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL		(1U << 1)
+#define BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP		(1U << 2)
+
 struct bpf_flow_keys {
 	__u16	nhoff;
 	__u16	thoff;
@@ -3525,6 +3646,8 @@ struct bpf_flow_keys {
 			__u32	ipv6_dst[4];	/* in6_addr; network order */
 		};
 	};
+	__u32	flags;
+	__be32	flow_label;
 };
 
 struct bpf_func_info {

include/uapi/linux/if_link.h

@@ -167,6 +167,8 @@ enum {
 	IFLA_NEW_IFINDEX,
 	IFLA_MIN_MTU,
 	IFLA_MAX_MTU,
+	IFLA_PROP_LIST,
+	IFLA_ALT_IFNAME, /* Alternative ifname */
 	__IFLA_MAX
 };
 
@@ -695,6 +697,7 @@ enum {
 	IFLA_VF_IB_NODE_GUID,	/* VF Infiniband node GUID */
 	IFLA_VF_IB_PORT_GUID,	/* VF Infiniband port GUID */
 	IFLA_VF_VLAN_LIST,	/* nested list of vlans, option for QinQ */
+	IFLA_VF_BROADCAST,	/* VF broadcast */
 	__IFLA_VF_MAX,
 };
 
@@ -705,6 +708,10 @@ struct ifla_vf_mac {
 	__u8 mac[32]; /* MAX_ADDR_LEN */
 };
 
+struct ifla_vf_broadcast {
+	__u8 broadcast[32];
+};
+
 struct ifla_vf_vlan {
 	__u32 vf;
 	__u32 vlan; /* 0 - 4095, 0 disables VLAN filter */

include/uapi/linux/if_xdp.h

@@ -16,6 +16,18 @@
 #define XDP_SHARED_UMEM	(1 << 0)
 #define XDP_COPY	(1 << 1) /* Force copy-mode */
 #define XDP_ZEROCOPY	(1 << 2) /* Force zero-copy mode */
+/* If this option is set, the driver might go sleep and in that case
+ * the XDP_RING_NEED_WAKEUP flag in the fill and/or Tx rings will be
+ * set. If it is set, the application need to explicitly wake up the
+ * driver with a poll() (Rx and Tx) or sendto() (Tx only). If you are
+ * running the driver and the application on the same core, you should
+ * use this option so that the kernel will yield to the user space
+ * application.
+ */
+#define XDP_USE_NEED_WAKEUP (1 << 3)
+
+/* Flags for xsk_umem_config flags */
+#define XDP_UMEM_UNALIGNED_CHUNK_FLAG (1 << 0)
 
 struct sockaddr_xdp {
 	__u16 sxdp_family;
@@ -25,10 +37,14 @@ struct sockaddr_xdp {
 	__u32 sxdp_shared_umem_fd;
 };
 
+/* XDP_RING flags */
+#define XDP_RING_NEED_WAKEUP (1 << 0)
+
 struct xdp_ring_offset {
 	__u64 producer;
 	__u64 consumer;
 	__u64 desc;
+	__u64 flags;
 };
 
 struct xdp_mmap_offsets {
@@ -53,6 +69,7 @@ struct xdp_umem_reg {
 	__u64 len; /* Length of packet data area */
 	__u32 chunk_size;
 	__u32 headroom;
+	__u32 flags;
 };
 
 struct xdp_statistics {
@@ -74,6 +91,11 @@ struct xdp_options {
 #define XDP_UMEM_PGOFF_FILL_RING	0x100000000ULL
 #define XDP_UMEM_PGOFF_COMPLETION_RING	0x180000000ULL
 
+/* Masks for unaligned chunks mode */
+#define XSK_UNALIGNED_BUF_OFFSET_SHIFT 48
+#define XSK_UNALIGNED_BUF_ADDR_MASK \
+	((1ULL << XSK_UNALIGNED_BUF_OFFSET_SHIFT) - 1)
+
 /* Rx/Tx descriptor */
 struct xdp_desc {
 	__u64 addr;

meson.build

@@ -1,95 +0,0 @@
-# SPDX-License-Identifier: LGPL-2.1 OR BSD-2-Clause
-project('libbpf', 'c',
-        version : '0.0.3',
-        license : 'LGPL-2.1 OR BSD-2-Clause',
-        default_options : [
-                'prefix=/usr',
-        ],
-        meson_version : '>= 0.46',
-        )
-
-patchlevel = meson.project_version().split('.')[1]
-
-libbpf_source_dir = './'
-
-libbpf_sources = files(run_command('find',
-        [
-        '@0@/src'.format(libbpf_source_dir),
-        '-type',
-        'f',
-        '-name',
-        '*.[h|c]']).stdout().split())
-
-libbpf_headers = files(
-        join_paths(libbpf_source_dir, 'src/bpf.h'),
-        join_paths(libbpf_source_dir, 'src/btf.h'),
-        join_paths(libbpf_source_dir, 'src/libbpf.h'))
-
-feature_rellocarray = run_command(join_paths(libbpf_source_dir, 'scripts/check-reallocarray.sh'))
-
-libbpf_c_args = ['-g',
-                '-O2',
-                '-Werror',
-                '-Wall',
-]
-
-if feature_rellocarray.stdout().strip() != ''
-        libbpf_c_args += '-DCOMPAT_NEED_REALLOCARRAY'
-endif
-
-# bpf_includes are required to include bpf.h, btf.h, libbpf.h
-bpf_includes = include_directories(
-        join_paths(libbpf_source_dir, 'src'))
-
-libbpf_includes = include_directories(
-        join_paths(libbpf_source_dir, 'include'),
-        join_paths(libbpf_source_dir, 'include/uapi'))
-
-libelf = dependency('libelf')
-libelf = dependency('libelf', required: false)
-if not libelf.found()
-        libelf = cc.find_library('elf', required: true)
-endif
-
-deps = [libelf]
-
-libbpf_static = static_library(
-        'bpf',
-        libbpf_sources,
-        c_args : libbpf_c_args,
-        dependencies : deps,
-        include_directories : libbpf_includes,
-        install : true)
-
-libbpf_static_dep = declare_dependency(link_with : libbpf_static)
-
-libbpf_map_source_path = join_paths(libbpf_source_dir, 'src/libbpf.map')
-libbpf_map_abs_path = join_paths(meson.current_source_dir(), libbpf_map_source_path)
-
-libbpf_c_args += ['-fPIC', '-fvisibility=hidden']
-
-libbpf_link_args = ['-Wl,--version-script=@0@'.format(libbpf_map_abs_path)]
-
-libbpf_shared = shared_library(
-        'bpf',
-        libbpf_sources,
-        c_args : libbpf_c_args,
-        dependencies : deps,
-        include_directories : libbpf_includes,
-        install : true,
-        link_args : libbpf_link_args,
-        link_depends : libbpf_map_source_path,
-        soversion : patchlevel,
-        version : meson.project_version())
-
-libbpf_shared_dep = declare_dependency(link_with : libbpf_shared)
-
-install_headers(libbpf_headers, subdir : 'bpf')
-
-pkg = import('pkgconfig')
-pkg.generate(
-        name: meson.project_name(),
-        version: meson.project_version(),
-        libraries: libbpf_shared,
-        requires_private: ['libelf'],
-        description: '''BPF library''')

scripts/coverity.sh

@@ -0,0 +1,105 @@
+#!/bin/bash
+# Taken from: https://scan.coverity.com/scripts/travisci_build_coverity_scan.sh
+# Local changes are annotated with "#[local]"
+
+set -e
+
+# Environment check
+echo -e "\033[33;1mNote: COVERITY_SCAN_PROJECT_NAME and COVERITY_SCAN_TOKEN are available on Project Settings page on scan.coverity.com\033[0m"
+[ -z "$COVERITY_SCAN_PROJECT_NAME" ] && echo "ERROR: COVERITY_SCAN_PROJECT_NAME must be set" && exit 1
+[ -z "$COVERITY_SCAN_NOTIFICATION_EMAIL" ] && echo "ERROR: COVERITY_SCAN_NOTIFICATION_EMAIL must be set" && exit 1
+[ -z "$COVERITY_SCAN_BRANCH_PATTERN" ] && echo "ERROR: COVERITY_SCAN_BRANCH_PATTERN must be set" && exit 1
+[ -z "$COVERITY_SCAN_BUILD_COMMAND" ] && echo "ERROR: COVERITY_SCAN_BUILD_COMMAND must be set" && exit 1
+[ -z "$COVERITY_SCAN_TOKEN" ] && echo "ERROR: COVERITY_SCAN_TOKEN must be set" && exit 1
+
+PLATFORM=`uname`
+#[local] Use /var/tmp for TOOL_ARCHIVE and TOOL_BASE, as on certain systems
+# /tmp is tmpfs and is sometimes too small to handle all necessary tooling
+TOOL_ARCHIVE=/var//tmp/cov-analysis-${PLATFORM}.tgz
+TOOL_URL=https://scan.coverity.com/download/${PLATFORM}
+TOOL_BASE=/var/tmp/coverity-scan-analysis
+UPLOAD_URL="https://scan.coverity.com/builds"
+SCAN_URL="https://scan.coverity.com"
+
+# Do not run on pull requests
+if [ "${TRAVIS_PULL_REQUEST}" = "true" ]; then
+  echo -e "\033[33;1mINFO: Skipping Coverity Analysis: branch is a pull request.\033[0m"
+  exit 0
+fi
+
+# Verify this branch should run
+IS_COVERITY_SCAN_BRANCH=`ruby -e "puts '${TRAVIS_BRANCH}' =~ /\\A$COVERITY_SCAN_BRANCH_PATTERN\\z/ ? 1 : 0"`
+if [ "$IS_COVERITY_SCAN_BRANCH" = "1" ]; then
+  echo -e "\033[33;1mCoverity Scan configured to run on branch ${TRAVIS_BRANCH}\033[0m"
+else
+  echo -e "\033[33;1mCoverity Scan NOT configured to run on branch ${TRAVIS_BRANCH}\033[0m"
+  exit 1
+fi
+
+# Verify upload is permitted
+AUTH_RES=`curl -s --form project="$COVERITY_SCAN_PROJECT_NAME" --form token="$COVERITY_SCAN_TOKEN" $SCAN_URL/api/upload_permitted`
+if [ "$AUTH_RES" = "Access denied" ]; then
+  echo -e "\033[33;1mCoverity Scan API access denied. Check COVERITY_SCAN_PROJECT_NAME and COVERITY_SCAN_TOKEN.\033[0m"
+  exit 1
+else
+  AUTH=`echo $AUTH_RES | ruby -e "require 'rubygems'; require 'json'; puts JSON[STDIN.read]['upload_permitted']"`
+  if [ "$AUTH" = "true" ]; then
+    echo -e "\033[33;1mCoverity Scan analysis authorized per quota.\033[0m"
+  else
+    WHEN=`echo $AUTH_RES | ruby -e "require 'rubygems'; require 'json'; puts JSON[STDIN.read]['next_upload_permitted_at']"`
+    echo -e "\033[33;1mCoverity Scan analysis NOT authorized until $WHEN.\033[0m"
+    exit 0
+  fi
+fi
+
+if [ ! -d $TOOL_BASE ]; then
+  # Download Coverity Scan Analysis Tool
+  if [ ! -e $TOOL_ARCHIVE ]; then
+    echo -e "\033[33;1mDownloading Coverity Scan Analysis Tool...\033[0m"
+    wget -nv -O $TOOL_ARCHIVE $TOOL_URL --post-data "project=$COVERITY_SCAN_PROJECT_NAME&token=$COVERITY_SCAN_TOKEN"
+  fi
+
+  # Extract Coverity Scan Analysis Tool
+  echo -e "\033[33;1mExtracting Coverity Scan Analysis Tool...\033[0m"
+  mkdir -p $TOOL_BASE
+  pushd $TOOL_BASE
+  tar xzf $TOOL_ARCHIVE
+  popd
+fi
+
+TOOL_DIR=`find $TOOL_BASE -type d -name 'cov-analysis*'`
+export PATH=$TOOL_DIR/bin:$PATH
+
+# Build
+echo -e "\033[33;1mRunning Coverity Scan Analysis Tool...\033[0m"
+COV_BUILD_OPTIONS=""
+#COV_BUILD_OPTIONS="--return-emit-failures 8 --parse-error-threshold 85"
+RESULTS_DIR="cov-int"
+eval "${COVERITY_SCAN_BUILD_COMMAND_PREPEND}"
+COVERITY_UNSUPPORTED=1 cov-build --dir $RESULTS_DIR $COV_BUILD_OPTIONS $COVERITY_SCAN_BUILD_COMMAND
+cov-import-scm --dir $RESULTS_DIR --scm git --log $RESULTS_DIR/scm_log.txt 2>&1
+
+# Upload results
+echo -e "\033[33;1mTarring Coverity Scan Analysis results...\033[0m"
+RESULTS_ARCHIVE=analysis-results.tgz
+tar czf $RESULTS_ARCHIVE $RESULTS_DIR
+SHA=`git rev-parse --short HEAD`
+
+echo -e "\033[33;1mUploading Coverity Scan Analysis results...\033[0m"
+response=$(curl \
+  --silent --write-out "\n%{http_code}\n" \
+  --form project=$COVERITY_SCAN_PROJECT_NAME \
+  --form token=$COVERITY_SCAN_TOKEN \
+  --form email=$COVERITY_SCAN_NOTIFICATION_EMAIL \
+  --form file=@$RESULTS_ARCHIVE \
+  --form version=$SHA \
+  --form description="Travis CI build" \
+  $UPLOAD_URL)
+status_code=$(echo "$response" | sed -n '$p')
+#[local] Coverity used to return 201 on success, but it's 200 now
+# See https://github.com/systemd/systemd/blob/master/tools/coverity.sh#L145
+if [ "$status_code" != "200" ]; then
+  TEXT=$(echo "$response" | sed '$d')
+  echo -e "\033[33;1mCoverity Scan upload failed: $TEXT.\033[0m"
+  exit 1
+fi

scripts/sync-kernel.sh

@@ -1,40 +1,212 @@
 #!/bin/bash
 
 usage () {
-    echo "USAGE: ./sync-kernel.sh <kernel-repo> <libbpf-repo> [<baseline-commit>]"
-    echo ""
-    echo "If <baseline-commit> is not specified, it's read from <libbpf-repo>/CHECKPOINT-COMMIT"
-    exit 1
+	echo "USAGE: ./sync-kernel.sh <libbpf-repo> <kernel-repo> <bpf-branch>"
+	echo ""
+	echo "Set BPF_NEXT_BASELINE to override bpf-next tree commit, otherwise read from <libbpf-repo>/CHECKPOINT-COMMIT."
+	echo "Set BPF_BASELINE to override bpf tree commit, otherwise read from <libbpf-repo>/BPF-CHECKPOINT-COMMIT."
+	echo "Set MANUAL_MODE to 1 to manually control every cherry-picked commits."
+	echo "Set IGNORE_CONSISTENCY to 1 to ignore failed contents consistency check."
+	exit 1
 }
 
-LINUX_REPO=${1-""}
-LIBBPF_REPO=${2-""}
-
-if [ -z "${LINUX_REPO}" ]; then
-    usage
-fi
-if [ -z "${LIBBPF_REPO}" ]; then
-    usage
-fi
-
 set -eu
 
-WORKDIR=$(pwd)
-trap "cd ${WORKDIR}; exit" INT TERM EXIT
+LIBBPF_REPO=${1-""}
+LINUX_REPO=${2-""}
+BPF_BRANCH=${3-""}
+BASELINE_COMMIT=${BPF_NEXT_BASELINE:-$(cat ${LIBBPF_REPO}/CHECKPOINT-COMMIT)}
+BPF_BASELINE_COMMIT=${BPF_BASELINE:-$(cat ${LIBBPF_REPO}/BPF-CHECKPOINT-COMMIT)}
 
-echo "WORKDIR:         ${WORKDIR}"
-echo "LINUX REPO:      ${LINUX_REPO}"
-echo "LIBBPF REPO:     ${LIBBPF_REPO}"
+if [ -z "${LIBBPF_REPO}" ] || [ -z "${LINUX_REPO}" ] || [ -z "${BPF_BRANCH}" ]; then
+	echo "Error: libbpf or linux repos are not specified"
+	usage
+fi
+if [ -z "${BPF_BRANCH}" ]; then
+	echo "Error: linux's bpf tree branch is not specified"
+	usage
+fi
+if [ -z "${BASELINE_COMMIT}" ] || [ -z "${BPF_BASELINE_COMMIT}" ]; then
+	echo "Error: bpf or bpf-next baseline commits are not provided"
+	usage
+fi
 
 SUFFIX=$(date --utc +%Y-%m-%dT%H-%M-%S.%3NZ)
-BASELINE_COMMIT=${3-$(cat ${LIBBPF_REPO}/CHECKPOINT-COMMIT)}
+WORKDIR=$(pwd)
+TMP_DIR=$(mktemp -d)
+
+trap "cd ${WORKDIR}; exit" INT TERM EXIT
+
+declare -A PATH_MAP
+PATH_MAP=(									\
+	[tools/lib/bpf]=src							\
+	[tools/include/uapi/linux/bpf_common.h]=include/uapi/linux/bpf_common.h	\
+	[tools/include/uapi/linux/bpf.h]=include/uapi/linux/bpf.h		\
+	[tools/include/uapi/linux/btf.h]=include/uapi/linux/btf.h		\
+	[tools/include/uapi/linux/if_link.h]=include/uapi/linux/if_link.h	\
+	[tools/include/uapi/linux/if_xdp.h]=include/uapi/linux/if_xdp.h		\
+	[tools/include/uapi/linux/netlink.h]=include/uapi/linux/netlink.h	\
+	[tools/include/tools/libc_compat.h]=include/tools/libc_compat.h		\
+)
+
+LIBBPF_PATHS="${!PATH_MAP[@]}"
+LIBBPF_VIEW_PATHS="${PATH_MAP[@]}"
+LIBBPF_VIEW_EXCLUDE_REGEX='^src/(Makefile|Build|test_libbpf\.c|bpf_helper_defs\.h|\.gitignore)$'
+
+LIBBPF_TREE_FILTER="mkdir -p __libbpf/include/uapi/linux __libbpf/include/tools && "$'\\\n'
+for p in "${!PATH_MAP[@]}"; do
+	LIBBPF_TREE_FILTER+="git mv -kf ${p} __libbpf/${PATH_MAP[${p}]} && "$'\\\n'
+done
+LIBBPF_TREE_FILTER+="git rm --ignore-unmatch -f __libbpf/src/{Makefile,Build,test_libbpf.c,.gitignore} >/dev/null"
+
+cd_to()
+{
+	cd ${WORKDIR} && cd "$1"
+}
+
+# Output brief single-line commit description
+# $1 - commit ref
+commit_desc()
+{
+	git log -n1 --pretty='%h ("%s")' $1
+}
+
+# Create commit single-line signature, which consists of:
+# - full commit hash
+# - author date in ISO8601 format
+# - full commit body with newlines replaced with vertical bars (|)
+# - shortstat appended at the end
+# The idea is that this single-line signature is good enough to make final
+# decision about whether two commits are the same, across different repos.
+# $1 - commit ref
+commit_signature()
+{
+	git log -n1 --pretty='("%s")|%aI|%b' --shortstat $1 | tr '\n' '|'
+}
+
+# Validate there are no non-empty merges (we can't handle them)
+# $1 - baseline tag
+# $2 - tip tag
+validate_merges()
+{
+	local baseline_tag=$1
+	local tip_tag=$2
+	local new_merges
+	local merge_change_cnt
+	local ignore_merge_resolutions
+	local desc
+
+	new_merges=$(git rev-list --merges --topo-order --reverse ${baseline_tag}..${tip_tag} ${LIBBPF_PATHS[@]})
+	for new_merge in ${new_merges}; do
+		desc=$(commit_desc ${new_merge})
+		echo "MERGE: ${desc}"
+		merge_change_cnt=$(git show --format='' ${new_merge} | wc -l)
+		if ((${merge_change_cnt} > 0)); then
+			read -p "Merge '${desc}' is non-empty, which will cause conflicts! Do you want to proceed? [y/N]: " ignore_merge_resolutions
+			case "${ignore_merge_resolutions}" in
+				"y" | "Y")
+					echo "Skipping '${desc}'..."
+					continue
+					;;
+			esac
+			exit 3
+		fi
+	done
+}
+
+# Cherry-pick commits touching libbpf-related files
+# $1 - baseline_tag
+# $2 - tip_tag
+cherry_pick_commits()
+{
+	local manual_mode=${MANUAL_MODE:-0}
+	local baseline_tag=$1
+	local tip_tag=$2
+	local new_commits
+	local signature
+	local should_skip
+	local synced_cnt
+	local manual_check
+	local libbpf_conflict_cnt
+	local desc
+
+	new_commits=$(git rev-list --no-merges --topo-order --reverse ${baseline_tag}..${tip_tag} ${LIBBPF_PATHS[@]})
+	for new_commit in ${new_commits}; do
+		desc="$(commit_desc ${new_commit})"
+		signature="$(commit_signature ${new_commit})"
+		synced_cnt=$(grep -F "${signature}" ${TMP_DIR}/libbpf_commits.txt | wc -l)
+		manual_check=0
+		if ((${synced_cnt} > 0)); then
+			# commit with the same subject is already in libbpf, but it's
+			# not 100% the same commit, so check with user
+			echo "Commit '${desc}' is synced into libbpf as:"
+			grep -F "${signature}" ${TMP_DIR}/libbpf_commits.txt | \
+				cut -d'|' -f1 | sed -e 's/^/- /'
+			if ((${manual_mode} != 1 && ${synced_cnt} == 1)); then
+				echo "Skipping '${desc}' due to unique match..."
+				continue
+			fi
+			if ((${synced_cnt} > 1)); then
+				echo "'${desc} matches multiple commits, please, double-check!"
+				manual_check=1
+			fi
+		fi
+		if ((${manual_mode} == 1 || ${manual_check} == 1)); then
+			read -p "Do you want to skip '${desc}'? [y/N]: " should_skip
+			case "${should_skip}" in
+				"y" | "Y")
+					echo "Skipping '${desc}'..."
+					continue
+					;;
+			esac
+		fi
+		# commit hasn't been synced into libbpf yet
+		echo "Picking '${desc}'..."
+		if ! git cherry-pick ${new_commit} &>/dev/null; then
+			echo "Warning! Cherry-picking '${desc} failed, checking if it's non-libbpf files causing problems..."
+			libbpf_conflict_cnt=$(git diff --name-only --diff-filter=U -- ${LIBBPF_PATHS[@]} | wc -l)
+			conflict_cnt=$(git diff --name-only | wc -l)
+
+			if ((${libbpf_conflict_cnt} == 0)); then
+				echo "Looks like only non-libbpf files have conflicts, ignoring..."
+				if ((${conflict_cnt} == 0)); then
+					echo "Empty cherry-pick, skipping it..."
+					git cherry-pick --abort
+					continue
+				fi
+
+				git add .
+				# GIT_EDITOR=true to avoid editor popping up to edit commit message
+				if ! GIT_EDITOR=true git cherry-pick --continue &>/dev/null; then
+					echo "Error! That still failed! Please resolve manually."
+				else
+					echo "Success! All cherry-pick conflicts were resolved for '${desc}'!"
+					continue
+				fi
+			fi
+
+			read -p "Error! Cherry-picking '${desc}' failed, please fix manually and press <return> to proceed..."
+		fi
+	done
+}
+
+cd_to ${LIBBPF_REPO}
+GITHUB_ABS_DIR=$(pwd)
+echo "Dumping existing libbpf commit signatures..."
+for h in $(git log --pretty='%h' -n500); do
+	echo $h "$(commit_signature $h)" >> ${TMP_DIR}/libbpf_commits.txt
+done
 
 # Use current kernel repo HEAD as a source of patches
-cd ${LINUX_REPO}
+cd_to ${LINUX_REPO}
+LINUX_ABS_DIR=$(pwd)
 TIP_SYM_REF=$(git symbolic-ref -q --short HEAD || git rev-parse HEAD)
 TIP_COMMIT=$(git rev-parse HEAD)
+BPF_TIP_COMMIT=$(git rev-parse ${BPF_BRANCH})
 BASELINE_TAG=libbpf-baseline-${SUFFIX}
 TIP_TAG=libbpf-tip-${SUFFIX}
+BPF_BASELINE_TAG=libbpf-bpf-baseline-${SUFFIX}
+BPF_TIP_TAG=libbpf-bpf-tip-${SUFFIX}
 VIEW_TAG=libbpf-view-${SUFFIX}
 LIBBPF_SYNC_TAG=libbpf-sync-${SUFFIX}
 
@@ -43,75 +215,41 @@ SQUASH_BASE_TAG=libbpf-squash-base-${SUFFIX}
 SQUASH_TIP_TAG=libbpf-squash-tip-${SUFFIX}
 SQUASH_COMMIT=$(git commit-tree ${BASELINE_COMMIT}^{tree} -m "BASELINE SQUASH ${BASELINE_COMMIT}")
 
-echo "SUFFIX:          ${SUFFIX}"
-echo "BASELINE COMMIT: $(git log --pretty=oneline --no-walk ${BASELINE_COMMIT})"
-echo "TIP COMMIT:      $(git log --pretty=oneline --no-walk ${TIP_COMMIT})"
-echo "SQUASH COMMIT:   ${SQUASH_COMMIT}"
-echo "BASELINE TAG:    ${BASELINE_TAG}"
-echo "TIP TAG:         ${TIP_TAG}"
-echo "SQUASH BASE TAG: ${SQUASH_BASE_TAG}"
-echo "SQUASH TIP TAG:  ${SQUASH_TIP_TAG}"
-echo "VIEW TAG:        ${VIEW_TAG}"
-echo "LIBBPF SYNC TAG: ${LIBBPF_SYNC_TAG}"
-
-TMP_DIR=$(mktemp -d)
-echo "TEMP DIR:        ${TMP_DIR}"
-echo "PATCHES+COVER:   ${TMP_DIR}/patches"
-echo "PATCHSET:        ${TMP_DIR}/patchset.patch"
+echo "WORKDIR:          ${WORKDIR}"
+echo "LINUX REPO:       ${LINUX_REPO}"
+echo "LIBBPF REPO:      ${LIBBPF_REPO}"
+echo "TEMP DIR:         ${TMP_DIR}"
+echo "SUFFIX:           ${SUFFIX}"
+echo "BASE COMMIT:      '$(commit_desc ${BASELINE_COMMIT})'"
+echo "TIP COMMIT:       '$(commit_desc ${TIP_COMMIT})'"
+echo "BPF BASE COMMIT:  '$(commit_desc ${BPF_BASELINE_COMMIT})'"
+echo "BPF TIP COMMIT:   '$(commit_desc ${BPF_TIP_COMMIT})'"
+echo "SQUASH COMMIT:    ${SQUASH_COMMIT}"
+echo "BASELINE TAG:     ${BASELINE_TAG}"
+echo "TIP TAG:          ${TIP_TAG}"
+echo "BPF BASELINE TAG: ${BPF_BASELINE_TAG}"
+echo "BPF TIP TAG:      ${BPF_TIP_TAG}"
+echo "SQUASH BASE TAG:  ${SQUASH_BASE_TAG}"
+echo "SQUASH TIP TAG:   ${SQUASH_TIP_TAG}"
+echo "VIEW TAG:         ${VIEW_TAG}"
+echo "LIBBPF SYNC TAG:  ${LIBBPF_SYNC_TAG}"
+echo "PATCHES:          ${TMP_DIR}/patches"
 
 git branch ${BASELINE_TAG} ${BASELINE_COMMIT}
 git branch ${TIP_TAG} ${TIP_COMMIT}
+git branch ${BPF_BASELINE_TAG} ${BPF_BASELINE_COMMIT}
+git branch ${BPF_TIP_TAG} ${BPF_TIP_COMMIT}
 git branch ${SQUASH_BASE_TAG} ${SQUASH_COMMIT}
 git checkout -b ${SQUASH_TIP_TAG} ${SQUASH_COMMIT}
 
+# Validate there are no non-empty merges in bpf-next and bpf trees
+validate_merges ${BASELINE_TAG} ${TIP_TAG}
+validate_merges ${BPF_BASELINE_TAG} ${BPF_TIP_TAG}
+
 # Cherry-pick new commits onto squashed baseline commit
-LIBBPF_PATHS=(tools/lib/bpf tools/include/uapi/linux/{bpf_common.h,bpf.h,btf.h,if_link.h,if_xdp.h,netlink.h} tools/include/tools/libc_compat.h)
+cherry_pick_commits ${BASELINE_TAG} ${TIP_TAG}
+cherry_pick_commits ${BPF_BASELINE_TAG} ${BPF_TIP_TAG}
 
-LIBBPF_NEW_MERGES=$(git rev-list --merges --topo-order --reverse ${BASELINE_TAG}..${TIP_TAG} ${LIBBPF_PATHS[@]})
-for LIBBPF_NEW_MERGE in ${LIBBPF_NEW_MERGES}; do
-	printf "MERGE:\t" && git log --oneline -n1 ${LIBBPF_NEW_MERGE}
-	MERGE_CHANGES=$(git log --format='' -n1 ${LIBBPF_NEW_MERGE} | wc -l)
-	if ((${MERGE_CHANGES} > 0)); then
-		echo "Merge is non empty, aborting!.."
-		exit 3
-	fi
-done
-
-cd ${WORKDIR} && cd ${LIBBPF_REPO}
-git log --oneline -n500 > ${TMP_DIR}/libbpf_commits.txt
-cd ${WORKDIR} && cd ${LINUX_REPO}
-
-LIBBPF_NEW_COMMITS=$(git rev-list --no-merges --topo-order --reverse ${BASELINE_TAG}..${TIP_TAG} ${LIBBPF_PATHS[@]})
-for LIBBPF_NEW_COMMIT in ${LIBBPF_NEW_COMMITS}; do
-	echo "Checking commit '${LIBBPF_NEW_COMMIT}'"
-	SYNCED_COMMITS=$(grep -F "$(git log -n1 --pretty=format:%s ${LIBBPF_NEW_COMMIT})" ${TMP_DIR}/libbpf_commits.txt || echo "")
-	if [ -n "${SYNCED_COMMITS}" ]; then
-		# commit with the same subject is already in libbpf, but it's not 100% the same commit, so check with user
-		echo "Commit '$(git log -n1 --oneline ${LIBBPF_NEW_COMMIT})' appears to be already synced into libbpf..."
-		echo "Corresponding libbpf commit(s):"
-		echo "${SYNCED_COMMITS}"
-		read -p "Do you want to skip it? [y/N]: " SHOULD_SKIP
-		case "${SHOULD_SKIP}" in 
-			"y" | "Y")
-				echo "Skipping '$(git log -n1 --oneline ${LIBBPF_NEW_COMMIT})'..."
-				continue
-				;;
-		esac
-	fi
-	# commit hasn't been synced into libbpf yet
-	if ! git cherry-pick ${LIBBPF_NEW_COMMIT}; then 
-		read -p "Cherry-picking '$(git log --oneline -n1 ${LIBBPF_NEW_COMMIT})' failed, please fix manually and press <return> to proceed..."
-	fi
-done
-
-LIBBPF_TREE_FILTER='												\
-    mkdir -p __libbpf/include/uapi/linux __libbpf/include/tools &&						\
-    git mv -kf tools/lib/bpf __libbpf/src &&									\
-    git mv -kf tools/include/uapi/linux/{bpf_common.h,bpf.h,btf.h,if_link.h,if_xdp.h,netlink.h}			\
-	       __libbpf/include/uapi/linux &&									\
-    git mv -kf tools/include/tools/libc_compat.h __libbpf/include/tools &&					\
-    git rm --ignore-unmatch -f __libbpf/src/{Makefile,Build,test_libbpf.cpp,.gitignore}				\
-'
 # Move all libbpf files into __libbpf directory.
 git filter-branch --prune-empty -f --tree-filter "${LIBBPF_TREE_FILTER}" ${SQUASH_TIP_TAG} ${SQUASH_BASE_TAG}
 # Make __libbpf a new root directory
@@ -126,59 +264,92 @@ fi
 
 # Exclude baseline commit and generate nice cover letter with summary
 git format-patch ${SQUASH_BASE_TAG}..${SQUASH_TIP_TAG} --cover-letter -o ${TMP_DIR}/patches
-# Now generate single-file patchset w/o cover to apply on top of libbpf repo
-git format-patch ${SQUASH_BASE_TAG}..${SQUASH_TIP_TAG} --stdout > ${TMP_DIR}/patchset.patch
 
-# Now is time to re-apply libbpf-related linux  patches to libbpf repo
-cd ${WORKDIR} && cd ${LIBBPF_REPO}
+# Now is time to re-apply libbpf-related linux patches to libbpf repo
+cd_to ${LIBBPF_REPO}
 git checkout -b ${LIBBPF_SYNC_TAG}
-git am --committer-date-is-author-date ${TMP_DIR}/patchset.patch
+
+for patch in $(ls -1 ${TMP_DIR}/patches | tail -n +2); do
+	if ! git am --committer-date-is-author-date "${TMP_DIR}/patches/${patch}"; then
+		read -p "Applying ${TMP_DIR}/patches/${patch} failed, please resolve manually and press <return> to proceed..."
+	fi
+done
+
+# Generate bpf_helper_defs.h and commit, if anything changed
+# restore Linux tip to use bpf_helpers_doc.py
+cd_to ${LINUX_REPO}
+git checkout ${TIP_TAG}
+# re-generate bpf_helper_defs.h
+cd_to ${LIBBPF_REPO}
+"${LINUX_ABS_DIR}/scripts/bpf_helpers_doc.py" --header			    \
+	--file include/uapi/linux/bpf.h > src/bpf_helper_defs.h
+# if anything changed, commit it
+helpers_changes=$(git status --porcelain src/bpf_helper_defs.h | wc -l)
+if ((${helpers_changes} == 1)); then
+	git add src/bpf_helper_defs.h
+	git commit -m "sync: auto-generate latest BPF helpers
+
+Latest changes to BPF helper definitions.
+" -- src/bpf_helper_defs.h
+fi
 
 # Use generated cover-letter as a template for "sync commit" with
 # baseline and checkpoint commits from kernel repo (and leave summary
 # from cover letter intact, of course)
 echo ${TIP_COMMIT} > CHECKPOINT-COMMIT &&					      \
+echo ${BPF_TIP_COMMIT} > BPF-CHECKPOINT-COMMIT &&				      \
 git add CHECKPOINT-COMMIT &&							      \
+git add BPF-CHECKPOINT-COMMIT &&						      \
 awk '/\*\*\* BLURB HERE \*\*\*/ {p=1} p' ${TMP_DIR}/patches/0000-cover-letter.patch | \
 sed "s/\*\*\* BLURB HERE \*\*\*/\
 sync: latest libbpf changes from kernel\n\
 \n\
 Syncing latest libbpf commits from kernel repository.\n\
-Baseline commit:   ${BASELINE_COMMIT}\n\
-Checkpoint commit: ${TIP_COMMIT}/" |						      \
+Baseline bpf-next commit:   ${BASELINE_COMMIT}\n\
+Checkpoint bpf-next commit: ${TIP_COMMIT}\n\
+Baseline bpf commit:        ${BPF_BASELINE_COMMIT}\n\
+Checkpoint bpf commit:      ${BPF_TIP_COMMIT}/" |				      \
 git commit --file=-
 
 echo "SUCCESS! ${COMMIT_CNT} commits synced."
 
 echo "Verifying Linux's and Github's libbpf state"
-LIBBPF_VIEW_PATHS=(src include/uapi/linux/{bpf_common.h,bpf.h,btf.h,if_link.h,if_xdp.h,netlink.h} include/tools/libc_compat.h)
-LIBBPF_VIEW_EXCLUDE_REGEX='^src/(Makefile|Build|test_libbpf.cpp|\.gitignore)$'
 
-cd ${WORKDIR} && cd ${LINUX_REPO}
-LINUX_ABS_DIR=$(pwd)
+cd_to ${LINUX_REPO}
 git checkout -b ${VIEW_TAG} ${TIP_COMMIT}
 git filter-branch -f --tree-filter "${LIBBPF_TREE_FILTER}" ${VIEW_TAG}^..${VIEW_TAG}
 git filter-branch -f --subdirectory-filter __libbpf ${VIEW_TAG}^..${VIEW_TAG}
 git ls-files -- ${LIBBPF_VIEW_PATHS[@]} > ${TMP_DIR}/linux-view.ls
 
-cd ${WORKDIR} && cd ${LIBBPF_REPO}
-GITHUB_ABS_DIR=$(pwd)
+cd_to ${LIBBPF_REPO}
 git ls-files -- ${LIBBPF_VIEW_PATHS[@]} | grep -v -E "${LIBBPF_VIEW_EXCLUDE_REGEX}" > ${TMP_DIR}/github-view.ls
 
 echo "Comparing list of files..."
-diff ${TMP_DIR}/linux-view.ls ${TMP_DIR}/github-view.ls
+diff -u ${TMP_DIR}/linux-view.ls ${TMP_DIR}/github-view.ls
 echo "Comparing file contents..."
+CONSISTENT=1
 for F in $(cat ${TMP_DIR}/linux-view.ls); do
-	diff "${LINUX_ABS_DIR}/${F}" "${GITHUB_ABS_DIR}/${F}"
+	if ! diff -u "${LINUX_ABS_DIR}/${F}" "${GITHUB_ABS_DIR}/${F}"; then
+		echo "${LINUX_ABS_DIR}/${F} and ${GITHUB_ABS_DIR}/${F} are different!"
+		CONSISTENT=0
+	fi
 done
-echo "Contents appear identical!"
+if ((${CONSISTENT} == 1)); then
+	echo "Great! Content is identical!"
+else
+	echo "Unfortunately, there are consistency problems!"
+	if ((${IGNORE_CONSISTENCY-0} != 1)); then
+		exit 4
+	fi
+fi
 
 echo "Cleaning up..."
 rm -r ${TMP_DIR}
-cd ${WORKDIR} && cd ${LINUX_REPO}
+cd_to ${LINUX_REPO}
 git checkout ${TIP_SYM_REF}
-git branch -D ${BASELINE_TAG} ${TIP_TAG} ${SQUASH_BASE_TAG} ${SQUASH_TIP_TAG} ${VIEW_TAG}
+git branch -D ${BASELINE_TAG} ${TIP_TAG} ${BPF_BASELINE_TAG} ${BPF_TIP_TAG} \
+	      ${SQUASH_BASE_TAG} ${SQUASH_TIP_TAG} ${VIEW_TAG}
 
-cd ${WORKDIR}
+cd_to .
 echo "DONE."
 

src/.gitignore

@@ -2,3 +2,5 @@
 *.a
 /libbpf.pc
 /libbpf.so*
+/staticobjs
+/sharedobjs

src/Makefile

@@ -1,10 +1,9 @@
 # SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
 
-VERSION = 0
-PATCHLEVEL = 0
-EXTRAVERSION = 3
-
-LIBBPF_VERSION	= $(VERSION).$(PATCHLEVEL).$(EXTRAVERSION)
+LIBBPF_VERSION := $(shell \
+	grep -oE '^LIBBPF_([0-9.]+)' libbpf.map | \
+	sort -rV | head -n1 | cut -d'_' -f2)
+LIBBPF_MAJOR_VERSION := $(firstword $(subst ., ,$(LIBBPF_VERSION)))
 
 TOPDIR = ..
 
@@ -16,12 +15,10 @@ ifneq ($(FEATURE_REALLOCARRAY),)
 	ALL_CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
 endif
 
-ifndef BUILD_STATIC_ONLY
-	ALL_CFLAGS += -fPIC -fvisibility=hidden
-endif
+SHARED_CFLAGS += -fPIC -fvisibility=hidden -DSHARED
 
 CFLAGS ?= -g -O2 -Werror -Wall
-ALL_CFLAGS += $(CFLAGS)
+ALL_CFLAGS += $(CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
 ALL_LDFLAGS += $(LDFLAGS)
 ifdef NO_PKG_CONFIG
 	ALL_LDFLAGS += -lelf
@@ -32,22 +29,27 @@ else
 endif
 
 OBJDIR ?= .
-
-OBJS := $(addprefix $(OBJDIR)/,bpf.o btf.o libbpf.o libbpf_errno.o netlink.o \
+SHARED_OBJDIR := $(OBJDIR)/sharedobjs
+STATIC_OBJDIR := $(OBJDIR)/staticobjs
+OBJS := bpf.o btf.o libbpf.o libbpf_errno.o netlink.o \
 	nlattr.o str_error.o libbpf_probes.o bpf_prog_linfo.o xsk.o \
-	btf_dump.o hashmap.o)
+	btf_dump.o hashmap.o
+SHARED_OBJS := $(addprefix $(SHARED_OBJDIR)/,$(OBJS))
+STATIC_OBJS := $(addprefix $(STATIC_OBJDIR)/,$(OBJS))
 
-LIBS := $(OBJDIR)/libbpf.a
+STATIC_LIBS := $(OBJDIR)/libbpf.a
 ifndef BUILD_STATIC_ONLY
-	LIBS += $(OBJDIR)/libbpf.so \
-		$(OBJDIR)/libbpf.so.$(VERSION) \
-		$(OBJDIR)/libbpf.so.$(LIBBPF_VERSION)
+	SHARED_LIBS := $(OBJDIR)/libbpf.so \
+		       $(OBJDIR)/libbpf.so.$(LIBBPF_MAJOR_VERSION) \
+		       $(OBJDIR)/libbpf.so.$(LIBBPF_VERSION)
 	VERSION_SCRIPT := libbpf.map
 endif
 
-HEADERS := bpf.h libbpf.h btf.h xsk.h libbpf_util.h
-UAPI_HEADERS := $(addprefix $(TOPDIR)/include/uapi/linux/,bpf.h bpf_common.h \
-	btf.h)
+HEADERS := bpf.h libbpf.h btf.h xsk.h libbpf_util.h \
+	   bpf_helpers.h bpf_helper_defs.h bpf_tracing.h \
+	   bpf_endian.h bpf_core_read.h
+UAPI_HEADERS := $(addprefix $(TOPDIR)/include/uapi/linux/,\
+			    bpf.h bpf_common.h btf.h)
 
 PC_FILE := $(OBJDIR)/libbpf.pc
 
@@ -66,21 +68,21 @@ LIBDIR ?= $(PREFIX)/$(LIBSUBDIR)
 INCLUDEDIR ?= $(PREFIX)/include
 UAPIDIR ?= $(PREFIX)/include
 
-all: $(LIBS) $(PC_FILE)
+all: $(STATIC_LIBS) $(SHARED_LIBS) $(PC_FILE)
 
-$(OBJDIR)/libbpf.a: $(OBJS)
+$(OBJDIR)/libbpf.a: $(STATIC_OBJS)
 	$(AR) rcs $@ $^
 
-$(OBJDIR)/libbpf.so: $(OBJDIR)/libbpf.so.$(VERSION)
+$(OBJDIR)/libbpf.so: $(OBJDIR)/libbpf.so.$(LIBBPF_MAJOR_VERSION)
 	ln -sf $(^F) $@
 
-$(OBJDIR)/libbpf.so.$(VERSION): $(OBJDIR)/libbpf.so.$(LIBBPF_VERSION)
+$(OBJDIR)/libbpf.so.$(LIBBPF_MAJOR_VERSION): $(OBJDIR)/libbpf.so.$(LIBBPF_VERSION)
 	ln -sf $(^F) $@
 
-$(OBJDIR)/libbpf.so.$(LIBBPF_VERSION): $(OBJS)
-	$(CC) -shared $(ALL_LDFLAGS) -Wl,--version-script=$(VERSION_SCRIPT) \
-				     -Wl,-soname,libbpf.so.$(VERSION) \
-				     $^ -o $@
+$(OBJDIR)/libbpf.so.$(LIBBPF_VERSION): $(SHARED_OBJS)
+	$(CC) -shared -Wl,--version-script=$(VERSION_SCRIPT) \
+		      -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
+		      $^ $(ALL_LDFLAGS) -o $@
 
 $(OBJDIR)/libbpf.pc:
 	sed -e "s|@PREFIX@|$(PREFIX)|" \
@@ -88,9 +90,18 @@ $(OBJDIR)/libbpf.pc:
 		-e "s|@VERSION@|$(LIBBPF_VERSION)|" \
 		< libbpf.pc.template > $@
 
-$(OBJDIR)/%.o: %.c
+$(STATIC_OBJDIR):
+	mkdir -p $(STATIC_OBJDIR)
+
+$(SHARED_OBJDIR):
+	mkdir -p $(SHARED_OBJDIR)
+
+$(STATIC_OBJDIR)/%.o: %.c | $(STATIC_OBJDIR)
 	$(CC) $(ALL_CFLAGS) $(CPPFLAGS) -c $< -o $@
 
+$(SHARED_OBJDIR)/%.o: %.c | $(SHARED_OBJDIR)
+	$(CC) $(ALL_CFLAGS) $(SHARED_CFLAGS) $(CPPFLAGS) -c $< -o $@
+
 define do_install
 	if [ ! -d '$(DESTDIR)$2' ]; then		\
 		$(INSTALL) -d -m 755 '$(DESTDIR)$2';	\
@@ -107,7 +118,7 @@ define do_s_install
 endef
 
 install: all install_headers install_pkgconfig
-	$(call do_s_install,$(LIBS),$(LIBDIR))
+	$(call do_s_install,$(STATIC_LIBS) $(SHARED_LIBS),$(LIBDIR))
 
 install_headers:
 	$(call do_install,$(HEADERS),$(INCLUDEDIR)/bpf,644)
@@ -121,4 +132,4 @@ install_pkgconfig: $(PC_FILE)
 	$(call do_install,$(PC_FILE),$(LIBDIR)/pkgconfig,644)
 
 clean:
-	rm -f *.o *.a *.so *.so.* *.pc
+	rm -rf *.o *.a *.so *.so.* *.pc $(SHARED_OBJDIR) $(STATIC_OBJDIR)

src/bpf.c

@@ -189,7 +189,7 @@ static void *
 alloc_zero_tailing_info(const void *orecord, __u32 cnt,
 			__u32 actual_rec_size, __u32 expected_rec_size)
 {
-	__u64 info_len = actual_rec_size * cnt;
+	__u64 info_len = (__u64)actual_rec_size * cnt;
 	void *info, *nrecord;
 	int i;
 
@@ -228,6 +228,13 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
 	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_TRACING) {
+		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.insns = ptr_to_u64(load_attr->insns);
 	attr.license = ptr_to_u64(load_attr->license);
@@ -241,8 +248,6 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
 		attr.log_size = 0;
 	}
 
-	attr.kern_version = load_attr->kern_version;
-	attr.prog_ifindex = load_attr->prog_ifindex;
 	attr.prog_btf_fd = load_attr->prog_btf_fd;
 	attr.func_info_rec_size = load_attr->func_info_rec_size;
 	attr.func_info_cnt = load_attr->func_info_cnt;
@@ -568,7 +573,7 @@ int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
 	return ret;
 }
 
-int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
+static int bpf_obj_get_next_id(__u32 start_id, __u32 *next_id, int cmd)
 {
 	union bpf_attr attr;
 	int err;
@@ -576,26 +581,26 @@ int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
 	memset(&attr, 0, sizeof(attr));
 	attr.start_id = start_id;
 
-	err = sys_bpf(BPF_PROG_GET_NEXT_ID, &attr, sizeof(attr));
+	err = sys_bpf(cmd, &attr, sizeof(attr));
 	if (!err)
 		*next_id = attr.next_id;
 
 	return err;
 }
 
+int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
+{
+	return bpf_obj_get_next_id(start_id, next_id, BPF_PROG_GET_NEXT_ID);
+}
+
 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
 {
-	union bpf_attr attr;
-	int err;
+	return bpf_obj_get_next_id(start_id, next_id, BPF_MAP_GET_NEXT_ID);
+}
 
-	memset(&attr, 0, sizeof(attr));
-	attr.start_id = start_id;
-
-	err = sys_bpf(BPF_MAP_GET_NEXT_ID, &attr, sizeof(attr));
-	if (!err)
-		*next_id = attr.next_id;
-
-	return err;
+int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id)
+{
+	return bpf_obj_get_next_id(start_id, next_id, BPF_BTF_GET_NEXT_ID);
 }
 
 int bpf_prog_get_fd_by_id(__u32 id)

src/bpf.h

@@ -77,8 +77,14 @@ struct bpf_load_program_attr {
 	const struct bpf_insn *insns;
 	size_t insns_cnt;
 	const char *license;
-	__u32 kern_version;
-	__u32 prog_ifindex;
+	union {
+		__u32 kern_version;
+		__u32 attach_prog_fd;
+	};
+	union {
+		__u32 prog_ifindex;
+		__u32 attach_btf_id;
+	};
 	__u32 prog_btf_fd;
 	__u32 func_info_rec_size;
 	const void *func_info;
@@ -156,6 +162,7 @@ LIBBPF_API int bpf_prog_test_run(int prog_fd, int repeat, void *data,
 				 __u32 *retval, __u32 *duration);
 LIBBPF_API int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id);
 LIBBPF_API int bpf_map_get_next_id(__u32 start_id, __u32 *next_id);
+LIBBPF_API int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id);
 LIBBPF_API int bpf_prog_get_fd_by_id(__u32 id);
 LIBBPF_API int bpf_map_get_fd_by_id(__u32 id);
 LIBBPF_API int bpf_btf_get_fd_by_id(__u32 id);

src/bpf_core_read.h

@@ -0,0 +1,263 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __BPF_CORE_READ_H__
+#define __BPF_CORE_READ_H__
+
+/*
+ * enum bpf_field_info_kind is passed as a second argument into
+ * __builtin_preserve_field_info() built-in to get a specific aspect of
+ * a field, captured as a first argument. __builtin_preserve_field_info(field,
+ * info_kind) returns __u32 integer and produces BTF field relocation, which
+ * is understood and processed by libbpf during BPF object loading. See
+ * selftests/bpf for examples.
+ */
+enum bpf_field_info_kind {
+	BPF_FIELD_BYTE_OFFSET = 0,	/* field byte offset */
+	BPF_FIELD_BYTE_SIZE = 1,
+	BPF_FIELD_EXISTS = 2,		/* field existence in target kernel */
+	BPF_FIELD_SIGNED = 3,
+	BPF_FIELD_LSHIFT_U64 = 4,
+	BPF_FIELD_RSHIFT_U64 = 5,
+};
+
+#define __CORE_RELO(src, field, info)					      \
+	__builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define __CORE_BITFIELD_PROBE_READ(dst, src, fld)			      \
+	bpf_probe_read((void *)dst,					      \
+		       __CORE_RELO(src, fld, BYTE_SIZE),		      \
+		       (const void *)src + __CORE_RELO(src, fld, BYTE_OFFSET))
+#else
+/* semantics of LSHIFT_64 assumes loading values into low-ordered bytes, so
+ * for big-endian we need to adjust destination pointer accordingly, based on
+ * field byte size
+ */
+#define __CORE_BITFIELD_PROBE_READ(dst, src, fld)			      \
+	bpf_probe_read((void *)dst + (8 - __CORE_RELO(src, fld, BYTE_SIZE)),  \
+		       __CORE_RELO(src, fld, BYTE_SIZE),		      \
+		       (const void *)src + __CORE_RELO(src, fld, BYTE_OFFSET))
+#endif
+
+/*
+ * Extract bitfield, identified by s->field, and return its value as u64.
+ * All this is done in relocatable manner, so bitfield changes such as
+ * signedness, bit size, offset changes, this will be handled automatically.
+ * This version of macro is using bpf_probe_read() to read underlying integer
+ * storage. Macro functions as an expression and its return type is
+ * bpf_probe_read()'s return value: 0, on success, <0 on error.
+ */
+#define BPF_CORE_READ_BITFIELD_PROBED(s, field) ({			      \
+	unsigned long long val = 0;					      \
+									      \
+	__CORE_BITFIELD_PROBE_READ(&val, s, field);			      \
+	val <<= __CORE_RELO(s, field, LSHIFT_U64);			      \
+	if (__CORE_RELO(s, field, SIGNED))				      \
+		val = ((long long)val) >> __CORE_RELO(s, field, RSHIFT_U64);  \
+	else								      \
+		val = val >> __CORE_RELO(s, field, RSHIFT_U64);		      \
+	val;								      \
+})
+
+/*
+ * Extract bitfield, identified by s->field, and return its value as u64.
+ * This version of macro is using direct memory reads and should be used from
+ * BPF program types that support such functionality (e.g., typed raw
+ * tracepoints).
+ */
+#define BPF_CORE_READ_BITFIELD(s, field) ({				      \
+	const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
+	unsigned long long val;						      \
+									      \
+	switch (__CORE_RELO(s, field, BYTE_SIZE)) {			      \
+	case 1: val = *(const unsigned char *)p;			      \
+	case 2: val = *(const unsigned short *)p;			      \
+	case 4: val = *(const unsigned int *)p;				      \
+	case 8: val = *(const unsigned long long *)p;			      \
+	}								      \
+	val <<= __CORE_RELO(s, field, LSHIFT_U64);			      \
+	if (__CORE_RELO(s, field, SIGNED))				      \
+		val = ((long long)val) >> __CORE_RELO(s, field, RSHIFT_U64);  \
+	else								      \
+		val = val >> __CORE_RELO(s, field, RSHIFT_U64);		      \
+	val;								      \
+})
+
+/*
+ * Convenience macro to check that field actually exists in target kernel's.
+ * Returns:
+ *    1, if matching field is present in target kernel;
+ *    0, if no matching field found.
+ */
+#define bpf_core_field_exists(field)					    \
+	__builtin_preserve_field_info(field, BPF_FIELD_EXISTS)
+
+/*
+ * Convenience macro to get byte size of a field. Works for integers,
+ * struct/unions, pointers, arrays, and enums.
+ */
+#define bpf_core_field_size(field)					    \
+	__builtin_preserve_field_info(field, BPF_FIELD_BYTE_SIZE)
+
+/*
+ * bpf_core_read() abstracts away bpf_probe_read() call and captures offset
+ * relocation for source address using __builtin_preserve_access_index()
+ * built-in, provided by Clang.
+ *
+ * __builtin_preserve_access_index() takes as an argument an expression of
+ * taking an address of a field within struct/union. It makes compiler emit
+ * a relocation, which records BTF type ID describing root struct/union and an
+ * accessor string which describes exact embedded field that was used to take
+ * an address. See detailed description of this relocation format and
+ * semantics in comments to struct bpf_field_reloc in libbpf_internal.h.
+ *
+ * This relocation allows libbpf to adjust BPF instruction to use correct
+ * actual field offset, based on target kernel BTF type that matches original
+ * (local) BTF, used to record relocation.
+ */
+#define bpf_core_read(dst, sz, src)					    \
+	bpf_probe_read(dst, sz,						    \
+		       (const void *)__builtin_preserve_access_index(src))
+
+/*
+ * bpf_core_read_str() is a thin wrapper around bpf_probe_read_str()
+ * additionally emitting BPF CO-RE field relocation for specified source
+ * argument.
+ */
+#define bpf_core_read_str(dst, sz, src)					    \
+	bpf_probe_read_str(dst, sz,					    \
+			   (const void *)__builtin_preserve_access_index(src))
+
+#define ___concat(a, b) a ## b
+#define ___apply(fn, n) ___concat(fn, n)
+#define ___nth(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, __11, N, ...) N
+
+/*
+ * return number of provided arguments; used for switch-based variadic macro
+ * definitions (see ___last, ___arrow, etc below)
+ */
+#define ___narg(...) ___nth(_, ##__VA_ARGS__, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
+/*
+ * return 0 if no arguments are passed, N - otherwise; used for
+ * recursively-defined macros to specify termination (0) case, and generic
+ * (N) case (e.g., ___read_ptrs, ___core_read)
+ */
+#define ___empty(...) ___nth(_, ##__VA_ARGS__, N, N, N, N, N, N, N, N, N, N, 0)
+
+#define ___last1(x) x
+#define ___last2(a, x) x
+#define ___last3(a, b, x) x
+#define ___last4(a, b, c, x) x
+#define ___last5(a, b, c, d, x) x
+#define ___last6(a, b, c, d, e, x) x
+#define ___last7(a, b, c, d, e, f, x) x
+#define ___last8(a, b, c, d, e, f, g, x) x
+#define ___last9(a, b, c, d, e, f, g, h, x) x
+#define ___last10(a, b, c, d, e, f, g, h, i, x) x
+#define ___last(...) ___apply(___last, ___narg(__VA_ARGS__))(__VA_ARGS__)
+
+#define ___nolast2(a, _) a
+#define ___nolast3(a, b, _) a, b
+#define ___nolast4(a, b, c, _) a, b, c
+#define ___nolast5(a, b, c, d, _) a, b, c, d
+#define ___nolast6(a, b, c, d, e, _) a, b, c, d, e
+#define ___nolast7(a, b, c, d, e, f, _) a, b, c, d, e, f
+#define ___nolast8(a, b, c, d, e, f, g, _) a, b, c, d, e, f, g
+#define ___nolast9(a, b, c, d, e, f, g, h, _) a, b, c, d, e, f, g, h
+#define ___nolast10(a, b, c, d, e, f, g, h, i, _) a, b, c, d, e, f, g, h, i
+#define ___nolast(...) ___apply(___nolast, ___narg(__VA_ARGS__))(__VA_ARGS__)
+
+#define ___arrow1(a) a
+#define ___arrow2(a, b) a->b
+#define ___arrow3(a, b, c) a->b->c
+#define ___arrow4(a, b, c, d) a->b->c->d
+#define ___arrow5(a, b, c, d, e) a->b->c->d->e
+#define ___arrow6(a, b, c, d, e, f) a->b->c->d->e->f
+#define ___arrow7(a, b, c, d, e, f, g) a->b->c->d->e->f->g
+#define ___arrow8(a, b, c, d, e, f, g, h) a->b->c->d->e->f->g->h
+#define ___arrow9(a, b, c, d, e, f, g, h, i) a->b->c->d->e->f->g->h->i
+#define ___arrow10(a, b, c, d, e, f, g, h, i, j) a->b->c->d->e->f->g->h->i->j
+#define ___arrow(...) ___apply(___arrow, ___narg(__VA_ARGS__))(__VA_ARGS__)
+
+#define ___type(...) typeof(___arrow(__VA_ARGS__))
+
+#define ___read(read_fn, dst, src_type, src, accessor)			    \
+	read_fn((void *)(dst), sizeof(*(dst)), &((src_type)(src))->accessor)
+
+/* "recursively" read a sequence of inner pointers using local __t var */
+#define ___rd_first(src, a) ___read(bpf_core_read, &__t, ___type(src), src, a);
+#define ___rd_last(...)							    \
+	___read(bpf_core_read, &__t,					    \
+		___type(___nolast(__VA_ARGS__)), __t, ___last(__VA_ARGS__));
+#define ___rd_p1(...) const void *__t; ___rd_first(__VA_ARGS__)
+#define ___rd_p2(...) ___rd_p1(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p3(...) ___rd_p2(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p4(...) ___rd_p3(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p5(...) ___rd_p4(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p6(...) ___rd_p5(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p7(...) ___rd_p6(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p8(...) ___rd_p7(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___rd_p9(...) ___rd_p8(___nolast(__VA_ARGS__)) ___rd_last(__VA_ARGS__)
+#define ___read_ptrs(src, ...)						    \
+	___apply(___rd_p, ___narg(__VA_ARGS__))(src, __VA_ARGS__)
+
+#define ___core_read0(fn, dst, src, a)					    \
+	___read(fn, dst, ___type(src), src, a);
+#define ___core_readN(fn, dst, src, ...)				    \
+	___read_ptrs(src, ___nolast(__VA_ARGS__))			    \
+	___read(fn, dst, ___type(src, ___nolast(__VA_ARGS__)), __t,	    \
+		___last(__VA_ARGS__));
+#define ___core_read(fn, dst, src, a, ...)				    \
+	___apply(___core_read, ___empty(__VA_ARGS__))(fn, dst,		    \
+						      src, a, ##__VA_ARGS__)
+
+/*
+ * BPF_CORE_READ_INTO() is a more performance-conscious variant of
+ * BPF_CORE_READ(), in which final field is read into user-provided storage.
+ * See BPF_CORE_READ() below for more details on general usage.
+ */
+#define BPF_CORE_READ_INTO(dst, src, a, ...)				    \
+	({								    \
+		___core_read(bpf_core_read, dst, src, a, ##__VA_ARGS__)	    \
+	})
+
+/*
+ * BPF_CORE_READ_STR_INTO() does same "pointer chasing" as
+ * BPF_CORE_READ() for intermediate pointers, but then executes (and returns
+ * corresponding error code) bpf_core_read_str() for final string read.
+ */
+#define BPF_CORE_READ_STR_INTO(dst, src, a, ...)			    \
+	({								    \
+		___core_read(bpf_core_read_str, dst, src, a, ##__VA_ARGS__) \
+	})
+
+/*
+ * BPF_CORE_READ() is used to simplify BPF CO-RE relocatable read, especially
+ * when there are few pointer chasing steps.
+ * E.g., what in non-BPF world (or in BPF w/ BCC) would be something like:
+ *	int x = s->a.b.c->d.e->f->g;
+ * can be succinctly achieved using BPF_CORE_READ as:
+ *	int x = BPF_CORE_READ(s, a.b.c, d.e, f, g);
+ *
+ * BPF_CORE_READ will decompose above statement into 4 bpf_core_read (BPF
+ * CO-RE relocatable bpf_probe_read() wrapper) calls, logically equivalent to:
+ * 1. const void *__t = s->a.b.c;
+ * 2. __t = __t->d.e;
+ * 3. __t = __t->f;
+ * 4. return __t->g;
+ *
+ * Equivalence is logical, because there is a heavy type casting/preservation
+ * involved, as well as all the reads are happening through bpf_probe_read()
+ * calls using __builtin_preserve_access_index() to emit CO-RE relocations.
+ *
+ * N.B. Only up to 9 "field accessors" are supported, which should be more
+ * than enough for any practical purpose.
+ */
+#define BPF_CORE_READ(src, a, ...)					    \
+	({								    \
+		___type(src, a, ##__VA_ARGS__) __r;			    \
+		BPF_CORE_READ_INTO(&__r, src, a, ##__VA_ARGS__);	    \
+		__r;							    \
+	})
+
+#endif
+

src/bpf_endian.h

@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __BPF_ENDIAN__
+#define __BPF_ENDIAN__
+
+#include <linux/stddef.h>
+#include <linux/swab.h>
+
+/* LLVM's BPF target selects the endianness of the CPU
+ * it compiles on, or the user specifies (bpfel/bpfeb),
+ * respectively. The used __BYTE_ORDER__ is defined by
+ * the compiler, we cannot rely on __BYTE_ORDER from
+ * libc headers, since it doesn't reflect the actual
+ * requested byte order.
+ *
+ * Note, LLVM's BPF target has different __builtin_bswapX()
+ * semantics. It does map to BPF_ALU | BPF_END | BPF_TO_BE
+ * in bpfel and bpfeb case, which means below, that we map
+ * to cpu_to_be16(). We could use it unconditionally in BPF
+ * case, but better not rely on it, so that this header here
+ * can be used from application and BPF program side, which
+ * use different targets.
+ */
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+# define __bpf_ntohs(x)			__builtin_bswap16(x)
+# define __bpf_htons(x)			__builtin_bswap16(x)
+# define __bpf_constant_ntohs(x)	___constant_swab16(x)
+# define __bpf_constant_htons(x)	___constant_swab16(x)
+# define __bpf_ntohl(x)			__builtin_bswap32(x)
+# define __bpf_htonl(x)			__builtin_bswap32(x)
+# define __bpf_constant_ntohl(x)	___constant_swab32(x)
+# define __bpf_constant_htonl(x)	___constant_swab32(x)
+# define __bpf_be64_to_cpu(x)		__builtin_bswap64(x)
+# define __bpf_cpu_to_be64(x)		__builtin_bswap64(x)
+# define __bpf_constant_be64_to_cpu(x)	___constant_swab64(x)
+# define __bpf_constant_cpu_to_be64(x)	___constant_swab64(x)
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define __bpf_ntohs(x)			(x)
+# define __bpf_htons(x)			(x)
+# define __bpf_constant_ntohs(x)	(x)
+# define __bpf_constant_htons(x)	(x)
+# define __bpf_ntohl(x)			(x)
+# define __bpf_htonl(x)			(x)
+# define __bpf_constant_ntohl(x)	(x)
+# define __bpf_constant_htonl(x)	(x)
+# define __bpf_be64_to_cpu(x)		(x)
+# define __bpf_cpu_to_be64(x)		(x)
+# define __bpf_constant_be64_to_cpu(x)  (x)
+# define __bpf_constant_cpu_to_be64(x)  (x)
+#else
+# error "Fix your compiler's __BYTE_ORDER__?!"
+#endif
+
+#define bpf_htons(x)				\
+	(__builtin_constant_p(x) ?		\
+	 __bpf_constant_htons(x) : __bpf_htons(x))
+#define bpf_ntohs(x)				\
+	(__builtin_constant_p(x) ?		\
+	 __bpf_constant_ntohs(x) : __bpf_ntohs(x))
+#define bpf_htonl(x)				\
+	(__builtin_constant_p(x) ?		\
+	 __bpf_constant_htonl(x) : __bpf_htonl(x))
+#define bpf_ntohl(x)				\
+	(__builtin_constant_p(x) ?		\
+	 __bpf_constant_ntohl(x) : __bpf_ntohl(x))
+#define bpf_cpu_to_be64(x)			\
+	(__builtin_constant_p(x) ?		\
+	 __bpf_constant_cpu_to_be64(x) : __bpf_cpu_to_be64(x))
+#define bpf_be64_to_cpu(x)			\
+	(__builtin_constant_p(x) ?		\
+	 __bpf_constant_be64_to_cpu(x) : __bpf_be64_to_cpu(x))
+
+#endif /* __BPF_ENDIAN__ */

src/bpf_helpers.h

@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __BPF_HELPERS__
+#define __BPF_HELPERS__
+
+#include "bpf_helper_defs.h"
+
+#define __uint(name, val) int (*name)[val]
+#define __type(name, val) typeof(val) *name
+
+/* Helper macro to print out debug messages */
+#define bpf_printk(fmt, ...)				\
+({							\
+	char ____fmt[] = fmt;				\
+	bpf_trace_printk(____fmt, sizeof(____fmt),	\
+			 ##__VA_ARGS__);		\
+})
+
+/*
+ * Helper macro to place programs, maps, license in
+ * different sections in elf_bpf file. Section names
+ * are interpreted by elf_bpf loader
+ */
+#define SEC(NAME) __attribute__((section(NAME), used))
+
+#ifndef __always_inline
+#define __always_inline __attribute__((always_inline))
+#endif
+
+/*
+ * Helper structure used by eBPF C program
+ * to describe BPF map attributes to libbpf loader
+ */
+struct bpf_map_def {
+	unsigned int type;
+	unsigned int key_size;
+	unsigned int value_size;
+	unsigned int max_entries;
+	unsigned int map_flags;
+};
+
+enum libbpf_pin_type {
+	LIBBPF_PIN_NONE,
+	/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
+	LIBBPF_PIN_BY_NAME,
+};
+
+#endif

src/bpf_prog_linfo.c

@@ -101,6 +101,7 @@ struct bpf_prog_linfo *bpf_prog_linfo__new(const struct bpf_prog_info *info)
 {
 	struct bpf_prog_linfo *prog_linfo;
 	__u32 nr_linfo, nr_jited_func;
+	__u64 data_sz;
 
 	nr_linfo = info->nr_line_info;
 
@@ -122,11 +123,11 @@ struct bpf_prog_linfo *bpf_prog_linfo__new(const struct bpf_prog_info *info)
 	/* Copy xlated line_info */
 	prog_linfo->nr_linfo = nr_linfo;
 	prog_linfo->rec_size = info->line_info_rec_size;
-	prog_linfo->raw_linfo = malloc(nr_linfo * prog_linfo->rec_size);
+	data_sz = (__u64)nr_linfo * prog_linfo->rec_size;
+	prog_linfo->raw_linfo = malloc(data_sz);
 	if (!prog_linfo->raw_linfo)
 		goto err_free;
-	memcpy(prog_linfo->raw_linfo, (void *)(long)info->line_info,
-	       nr_linfo * prog_linfo->rec_size);
+	memcpy(prog_linfo->raw_linfo, (void *)(long)info->line_info, data_sz);
 
 	nr_jited_func = info->nr_jited_ksyms;
 	if (!nr_jited_func ||
@@ -142,13 +143,12 @@ struct bpf_prog_linfo *bpf_prog_linfo__new(const struct bpf_prog_info *info)
 	/* Copy jited_line_info */
 	prog_linfo->nr_jited_func = nr_jited_func;
 	prog_linfo->jited_rec_size = info->jited_line_info_rec_size;
-	prog_linfo->raw_jited_linfo = malloc(nr_linfo *
-					     prog_linfo->jited_rec_size);
+	data_sz = (__u64)nr_linfo * prog_linfo->jited_rec_size;
+	prog_linfo->raw_jited_linfo = malloc(data_sz);
 	if (!prog_linfo->raw_jited_linfo)
 		goto err_free;
 	memcpy(prog_linfo->raw_jited_linfo,
-	       (void *)(long)info->jited_line_info,
-	       nr_linfo * prog_linfo->jited_rec_size);
+	       (void *)(long)info->jited_line_info, data_sz);
 
 	/* Number of jited_line_info per jited func */
 	prog_linfo->nr_jited_linfo_per_func = malloc(nr_jited_func *

src/bpf_tracing.h

@@ -0,0 +1,195 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __BPF_TRACING_H__
+#define __BPF_TRACING_H__
+
+/* Scan the ARCH passed in from ARCH env variable (see Makefile) */
+#if defined(__TARGET_ARCH_x86)
+	#define bpf_target_x86
+	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_s390)
+	#define bpf_target_s390
+	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_arm)
+	#define bpf_target_arm
+	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_arm64)
+	#define bpf_target_arm64
+	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_mips)
+	#define bpf_target_mips
+	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_powerpc)
+	#define bpf_target_powerpc
+	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_sparc)
+	#define bpf_target_sparc
+	#define bpf_target_defined
+#else
+	#undef bpf_target_defined
+#endif
+
+/* Fall back to what the compiler says */
+#ifndef bpf_target_defined
+#if defined(__x86_64__)
+	#define bpf_target_x86
+#elif defined(__s390__)
+	#define bpf_target_s390
+#elif defined(__arm__)
+	#define bpf_target_arm
+#elif defined(__aarch64__)
+	#define bpf_target_arm64
+#elif defined(__mips__)
+	#define bpf_target_mips
+#elif defined(__powerpc__)
+	#define bpf_target_powerpc
+#elif defined(__sparc__)
+	#define bpf_target_sparc
+#endif
+#endif
+
+#if defined(bpf_target_x86)
+
+#ifdef __KERNEL__
+#define PT_REGS_PARM1(x) ((x)->di)
+#define PT_REGS_PARM2(x) ((x)->si)
+#define PT_REGS_PARM3(x) ((x)->dx)
+#define PT_REGS_PARM4(x) ((x)->cx)
+#define PT_REGS_PARM5(x) ((x)->r8)
+#define PT_REGS_RET(x) ((x)->sp)
+#define PT_REGS_FP(x) ((x)->bp)
+#define PT_REGS_RC(x) ((x)->ax)
+#define PT_REGS_SP(x) ((x)->sp)
+#define PT_REGS_IP(x) ((x)->ip)
+#else
+#ifdef __i386__
+/* i386 kernel is built with -mregparm=3 */
+#define PT_REGS_PARM1(x) ((x)->eax)
+#define PT_REGS_PARM2(x) ((x)->edx)
+#define PT_REGS_PARM3(x) ((x)->ecx)
+#define PT_REGS_PARM4(x) 0
+#define PT_REGS_PARM5(x) 0
+#define PT_REGS_RET(x) ((x)->esp)
+#define PT_REGS_FP(x) ((x)->ebp)
+#define PT_REGS_RC(x) ((x)->eax)
+#define PT_REGS_SP(x) ((x)->esp)
+#define PT_REGS_IP(x) ((x)->eip)
+#else
+#define PT_REGS_PARM1(x) ((x)->rdi)
+#define PT_REGS_PARM2(x) ((x)->rsi)
+#define PT_REGS_PARM3(x) ((x)->rdx)
+#define PT_REGS_PARM4(x) ((x)->rcx)
+#define PT_REGS_PARM5(x) ((x)->r8)
+#define PT_REGS_RET(x) ((x)->rsp)
+#define PT_REGS_FP(x) ((x)->rbp)
+#define PT_REGS_RC(x) ((x)->rax)
+#define PT_REGS_SP(x) ((x)->rsp)
+#define PT_REGS_IP(x) ((x)->rip)
+#endif
+#endif
+
+#elif defined(bpf_target_s390)
+
+/* s390 provides user_pt_regs instead of struct pt_regs to userspace */
+struct pt_regs;
+#define PT_REGS_S390 const volatile user_pt_regs
+#define PT_REGS_PARM1(x) (((PT_REGS_S390 *)(x))->gprs[2])
+#define PT_REGS_PARM2(x) (((PT_REGS_S390 *)(x))->gprs[3])
+#define PT_REGS_PARM3(x) (((PT_REGS_S390 *)(x))->gprs[4])
+#define PT_REGS_PARM4(x) (((PT_REGS_S390 *)(x))->gprs[5])
+#define PT_REGS_PARM5(x) (((PT_REGS_S390 *)(x))->gprs[6])
+#define PT_REGS_RET(x) (((PT_REGS_S390 *)(x))->gprs[14])
+/* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_FP(x) (((PT_REGS_S390 *)(x))->gprs[11])
+#define PT_REGS_RC(x) (((PT_REGS_S390 *)(x))->gprs[2])
+#define PT_REGS_SP(x) (((PT_REGS_S390 *)(x))->gprs[15])
+#define PT_REGS_IP(x) (((PT_REGS_S390 *)(x))->psw.addr)
+
+#elif defined(bpf_target_arm)
+
+#define PT_REGS_PARM1(x) ((x)->uregs[0])
+#define PT_REGS_PARM2(x) ((x)->uregs[1])
+#define PT_REGS_PARM3(x) ((x)->uregs[2])
+#define PT_REGS_PARM4(x) ((x)->uregs[3])
+#define PT_REGS_PARM5(x) ((x)->uregs[4])
+#define PT_REGS_RET(x) ((x)->uregs[14])
+#define PT_REGS_FP(x) ((x)->uregs[11]) /* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_RC(x) ((x)->uregs[0])
+#define PT_REGS_SP(x) ((x)->uregs[13])
+#define PT_REGS_IP(x) ((x)->uregs[12])
+
+#elif defined(bpf_target_arm64)
+
+/* arm64 provides struct user_pt_regs instead of struct pt_regs to userspace */
+struct pt_regs;
+#define PT_REGS_ARM64 const volatile struct user_pt_regs
+#define PT_REGS_PARM1(x) (((PT_REGS_ARM64 *)(x))->regs[0])
+#define PT_REGS_PARM2(x) (((PT_REGS_ARM64 *)(x))->regs[1])
+#define PT_REGS_PARM3(x) (((PT_REGS_ARM64 *)(x))->regs[2])
+#define PT_REGS_PARM4(x) (((PT_REGS_ARM64 *)(x))->regs[3])
+#define PT_REGS_PARM5(x) (((PT_REGS_ARM64 *)(x))->regs[4])
+#define PT_REGS_RET(x) (((PT_REGS_ARM64 *)(x))->regs[30])
+/* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_FP(x) (((PT_REGS_ARM64 *)(x))->regs[29])
+#define PT_REGS_RC(x) (((PT_REGS_ARM64 *)(x))->regs[0])
+#define PT_REGS_SP(x) (((PT_REGS_ARM64 *)(x))->sp)
+#define PT_REGS_IP(x) (((PT_REGS_ARM64 *)(x))->pc)
+
+#elif defined(bpf_target_mips)
+
+#define PT_REGS_PARM1(x) ((x)->regs[4])
+#define PT_REGS_PARM2(x) ((x)->regs[5])
+#define PT_REGS_PARM3(x) ((x)->regs[6])
+#define PT_REGS_PARM4(x) ((x)->regs[7])
+#define PT_REGS_PARM5(x) ((x)->regs[8])
+#define PT_REGS_RET(x) ((x)->regs[31])
+#define PT_REGS_FP(x) ((x)->regs[30]) /* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_RC(x) ((x)->regs[1])
+#define PT_REGS_SP(x) ((x)->regs[29])
+#define PT_REGS_IP(x) ((x)->cp0_epc)
+
+#elif defined(bpf_target_powerpc)
+
+#define PT_REGS_PARM1(x) ((x)->gpr[3])
+#define PT_REGS_PARM2(x) ((x)->gpr[4])
+#define PT_REGS_PARM3(x) ((x)->gpr[5])
+#define PT_REGS_PARM4(x) ((x)->gpr[6])
+#define PT_REGS_PARM5(x) ((x)->gpr[7])
+#define PT_REGS_RC(x) ((x)->gpr[3])
+#define PT_REGS_SP(x) ((x)->sp)
+#define PT_REGS_IP(x) ((x)->nip)
+
+#elif defined(bpf_target_sparc)
+
+#define PT_REGS_PARM1(x) ((x)->u_regs[UREG_I0])
+#define PT_REGS_PARM2(x) ((x)->u_regs[UREG_I1])
+#define PT_REGS_PARM3(x) ((x)->u_regs[UREG_I2])
+#define PT_REGS_PARM4(x) ((x)->u_regs[UREG_I3])
+#define PT_REGS_PARM5(x) ((x)->u_regs[UREG_I4])
+#define PT_REGS_RET(x) ((x)->u_regs[UREG_I7])
+#define PT_REGS_RC(x) ((x)->u_regs[UREG_I0])
+#define PT_REGS_SP(x) ((x)->u_regs[UREG_FP])
+
+/* Should this also be a bpf_target check for the sparc case? */
+#if defined(__arch64__)
+#define PT_REGS_IP(x) ((x)->tpc)
+#else
+#define PT_REGS_IP(x) ((x)->pc)
+#endif
+
+#endif
+
+#if defined(bpf_target_powerpc)
+#define BPF_KPROBE_READ_RET_IP(ip, ctx)		({ (ip) = (ctx)->link; })
+#define BPF_KRETPROBE_READ_RET_IP		BPF_KPROBE_READ_RET_IP
+#elif defined(bpf_target_sparc)
+#define BPF_KPROBE_READ_RET_IP(ip, ctx)		({ (ip) = PT_REGS_RET(ctx); })
+#define BPF_KRETPROBE_READ_RET_IP		BPF_KPROBE_READ_RET_IP
+#else
+#define BPF_KPROBE_READ_RET_IP(ip, ctx)					    \
+	({ bpf_probe_read(&(ip), sizeof(ip), (void *)PT_REGS_RET(ctx)); })
+#define BPF_KRETPROBE_READ_RET_IP(ip, ctx)				    \
+	({ bpf_probe_read(&(ip), sizeof(ip),				    \
+			  (void *)(PT_REGS_FP(ctx) + sizeof(ip))); })
+#endif
+
+#endif

src/btf.c

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
 /* Copyright (c) 2018 Facebook */
 
+#include <endian.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -19,13 +20,6 @@
 #define BTF_MAX_NR_TYPES 0x7fffffff
 #define BTF_MAX_STR_OFFSET 0x7fffffff
 
-#define IS_MODIFIER(k) (((k) == BTF_KIND_TYPEDEF) || \
-		((k) == BTF_KIND_VOLATILE) || \
-		((k) == BTF_KIND_CONST) || \
-		((k) == BTF_KIND_RESTRICT))
-
-#define IS_VAR(k) ((k) == BTF_KIND_VAR)
-
 static struct btf_type btf_void;
 
 struct btf {
@@ -42,47 +36,6 @@ struct btf {
 	int fd;
 };
 
-struct btf_ext_info {
-	/*
-	 * info points to the individual info section (e.g. func_info and
-	 * line_info) from the .BTF.ext. It does not include the __u32 rec_size.
-	 */
-	void *info;
-	__u32 rec_size;
-	__u32 len;
-};
-
-struct btf_ext {
-	union {
-		struct btf_ext_header *hdr;
-		void *data;
-	};
-	struct btf_ext_info func_info;
-	struct btf_ext_info line_info;
-	__u32 data_size;
-};
-
-struct btf_ext_info_sec {
-	__u32	sec_name_off;
-	__u32	num_info;
-	/* Followed by num_info * record_size number of bytes */
-	__u8	data[0];
-};
-
-/* The minimum bpf_func_info checked by the loader */
-struct bpf_func_info_min {
-	__u32   insn_off;
-	__u32   type_id;
-};
-
-/* The minimum bpf_line_info checked by the loader */
-struct bpf_line_info_min {
-	__u32	insn_off;
-	__u32	file_name_off;
-	__u32	line_off;
-	__u32	line_col;
-};
-
 static inline __u64 ptr_to_u64(const void *ptr)
 {
 	return (__u64) (unsigned long) ptr;
@@ -192,9 +145,9 @@ static int btf_parse_str_sec(struct btf *btf)
 static int btf_type_size(struct btf_type *t)
 {
 	int base_size = sizeof(struct btf_type);
-	__u16 vlen = BTF_INFO_VLEN(t->info);
+	__u16 vlen = btf_vlen(t);
 
-	switch (BTF_INFO_KIND(t->info)) {
+	switch (btf_kind(t)) {
 	case BTF_KIND_FWD:
 	case BTF_KIND_CONST:
 	case BTF_KIND_VOLATILE:
@@ -219,7 +172,7 @@ static int btf_type_size(struct btf_type *t)
 	case BTF_KIND_DATASEC:
 		return base_size + vlen * sizeof(struct btf_var_secinfo);
 	default:
-		pr_debug("Unsupported BTF_KIND:%u\n", BTF_INFO_KIND(t->info));
+		pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t));
 		return -EINVAL;
 	}
 }
@@ -263,7 +216,7 @@ const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id)
 
 static bool btf_type_is_void(const struct btf_type *t)
 {
-	return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
+	return t == &btf_void || btf_is_fwd(t);
 }
 
 static bool btf_type_is_void_or_null(const struct btf_type *t)
@@ -284,7 +237,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
 	t = btf__type_by_id(btf, type_id);
 	for (i = 0; i < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t);
 	     i++) {
-		switch (BTF_INFO_KIND(t->info)) {
+		switch (btf_kind(t)) {
 		case BTF_KIND_INT:
 		case BTF_KIND_STRUCT:
 		case BTF_KIND_UNION:
@@ -303,7 +256,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
 			type_id = t->type;
 			break;
 		case BTF_KIND_ARRAY:
-			array = (const struct btf_array *)(t + 1);
+			array = btf_array(t);
 			if (nelems && array->nelems > UINT32_MAX / nelems)
 				return -E2BIG;
 			nelems *= array->nelems;
@@ -316,10 +269,9 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id)
 		t = btf__type_by_id(btf, type_id);
 	}
 
+done:
 	if (size < 0)
 		return -EINVAL;
-
-done:
 	if (nelems && size > UINT32_MAX / nelems)
 		return -E2BIG;
 
@@ -334,8 +286,7 @@ int btf__resolve_type(const struct btf *btf, __u32 type_id)
 	t = btf__type_by_id(btf, type_id);
 	while (depth < MAX_RESOLVE_DEPTH &&
 	       !btf_type_is_void_or_null(t) &&
-	       (IS_MODIFIER(BTF_INFO_KIND(t->info)) ||
-		IS_VAR(BTF_INFO_KIND(t->info)))) {
+	       (btf_is_mod(t) || btf_is_typedef(t) || btf_is_var(t))) {
 		type_id = t->type;
 		t = btf__type_by_id(btf, type_id);
 		depth++;
@@ -365,6 +316,28 @@ __s32 btf__find_by_name(const struct btf *btf, const char *type_name)
 	return -ENOENT;
 }
 
+__s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name,
+			     __u32 kind)
+{
+	__u32 i;
+
+	if (kind == BTF_KIND_UNKN || !strcmp(type_name, "void"))
+		return 0;
+
+	for (i = 1; i <= btf->nr_types; i++) {
+		const struct btf_type *t = btf->types[i];
+		const char *name;
+
+		if (btf_kind(t) != kind)
+			continue;
+		name = btf__name_by_offset(btf, t->name_off);
+		if (name && !strcmp(type_name, name))
+			return i;
+	}
+
+	return -ENOENT;
+}
+
 void btf__free(struct btf *btf)
 {
 	if (!btf)
@@ -419,9 +392,9 @@ done:
 
 static bool btf_check_endianness(const GElf_Ehdr *ehdr)
 {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#if __BYTE_ORDER == __LITTLE_ENDIAN
 	return ehdr->e_ident[EI_DATA] == ELFDATA2LSB;
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#elif __BYTE_ORDER == __BIG_ENDIAN
 	return ehdr->e_ident[EI_DATA] == ELFDATA2MSB;
 #else
 # error "Unrecognized __BYTE_ORDER__"
@@ -438,14 +411,14 @@ struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext)
 	GElf_Ehdr ehdr;
 
 	if (elf_version(EV_CURRENT) == EV_NONE) {
-		pr_warning("failed to init libelf for %s\n", path);
+		pr_warn("failed to init libelf for %s\n", path);
 		return ERR_PTR(-LIBBPF_ERRNO__LIBELF);
 	}
 
 	fd = open(path, O_RDONLY);
 	if (fd < 0) {
 		err = -errno;
-		pr_warning("failed to open %s: %s\n", path, strerror(errno));
+		pr_warn("failed to open %s: %s\n", path, strerror(errno));
 		return ERR_PTR(err);
 	}
 
@@ -453,19 +426,19 @@ struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext)
 
 	elf = elf_begin(fd, ELF_C_READ, NULL);
 	if (!elf) {
-		pr_warning("failed to open %s as ELF file\n", path);
+		pr_warn("failed to open %s as ELF file\n", path);
 		goto done;
 	}
 	if (!gelf_getehdr(elf, &ehdr)) {
-		pr_warning("failed to get EHDR from %s\n", path);
+		pr_warn("failed to get EHDR from %s\n", path);
 		goto done;
 	}
 	if (!btf_check_endianness(&ehdr)) {
-		pr_warning("non-native ELF endianness is not supported\n");
+		pr_warn("non-native ELF endianness is not supported\n");
 		goto done;
 	}
 	if (!elf_rawdata(elf_getscn(elf, ehdr.e_shstrndx), NULL)) {
-		pr_warning("failed to get e_shstrndx from %s\n", path);
+		pr_warn("failed to get e_shstrndx from %s\n", path);
 		goto done;
 	}
 
@@ -475,29 +448,29 @@ struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext)
 
 		idx++;
 		if (gelf_getshdr(scn, &sh) != &sh) {
-			pr_warning("failed to get section(%d) header from %s\n",
-				   idx, path);
+			pr_warn("failed to get section(%d) header from %s\n",
+				idx, path);
 			goto done;
 		}
 		name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name);
 		if (!name) {
-			pr_warning("failed to get section(%d) name from %s\n",
-				   idx, path);
+			pr_warn("failed to get section(%d) name from %s\n",
+				idx, path);
 			goto done;
 		}
 		if (strcmp(name, BTF_ELF_SEC) == 0) {
 			btf_data = elf_getdata(scn, 0);
 			if (!btf_data) {
-				pr_warning("failed to get section(%d, %s) data from %s\n",
-					   idx, name, path);
+				pr_warn("failed to get section(%d, %s) data from %s\n",
+					idx, name, path);
 				goto done;
 			}
 			continue;
 		} else if (btf_ext && strcmp(name, BTF_EXT_ELF_SEC) == 0) {
 			btf_ext_data = elf_getdata(scn, 0);
 			if (!btf_ext_data) {
-				pr_warning("failed to get section(%d, %s) data from %s\n",
-					   idx, name, path);
+				pr_warn("failed to get section(%d, %s) data from %s\n",
+					idx, name, path);
 				goto done;
 			}
 			continue;
@@ -554,11 +527,11 @@ static int compare_vsi_off(const void *_a, const void *_b)
 static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
 			     struct btf_type *t)
 {
-	__u32 size = 0, off = 0, i, vars = BTF_INFO_VLEN(t->info);
+	__u32 size = 0, off = 0, i, vars = btf_vlen(t);
 	const char *name = btf__name_by_offset(btf, t->name_off);
 	const struct btf_type *t_var;
 	struct btf_var_secinfo *vsi;
-	struct btf_var *var;
+	const struct btf_var *var;
 	int ret;
 
 	if (!name) {
@@ -574,12 +547,11 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
 
 	t->size = size;
 
-	for (i = 0, vsi = (struct btf_var_secinfo *)(t + 1);
-	     i < vars; i++, vsi++) {
+	for (i = 0, vsi = btf_var_secinfos(t); i < vars; i++, vsi++) {
 		t_var = btf__type_by_id(btf, vsi->type);
-		var = (struct btf_var *)(t_var + 1);
+		var = btf_var(t_var);
 
-		if (BTF_INFO_KIND(t_var->info) != BTF_KIND_VAR) {
+		if (!btf_is_var(t_var)) {
 			pr_debug("Non-VAR type seen in section %s\n", name);
 			return -EINVAL;
 		}
@@ -595,7 +567,8 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
 
 		ret = bpf_object__variable_offset(obj, name, &off);
 		if (ret) {
-			pr_debug("No offset found in symbol table for VAR %s\n", name);
+			pr_debug("No offset found in symbol table for VAR %s\n",
+				 name);
 			return -ENOENT;
 		}
 
@@ -619,7 +592,7 @@ int btf__finalize_data(struct bpf_object *obj, struct btf *btf)
 		 * is section size and global variable offset. We use
 		 * the info from the ELF itself for this purpose.
 		 */
-		if (BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC) {
+		if (btf_is_datasec(t)) {
 			err = btf_fixup_datasec(obj, btf, t);
 			if (err)
 				break;
@@ -648,9 +621,9 @@ int btf__load(struct btf *btf)
 			       log_buf, log_buf_size, false);
 	if (btf->fd < 0) {
 		err = -errno;
-		pr_warning("Error loading BTF: %s(%d)\n", strerror(errno), errno);
+		pr_warn("Error loading BTF: %s(%d)\n", strerror(errno), errno);
 		if (*log_buf)
-			pr_warning("%s\n", log_buf);
+			pr_warn("%s\n", log_buf);
 		goto done;
 	}
 
@@ -755,8 +728,8 @@ int btf__get_map_kv_tids(const struct btf *btf, const char *map_name,
 
 	if (snprintf(container_name, max_name, "____btf_map_%s", map_name) ==
 	    max_name) {
-		pr_warning("map:%s length of '____btf_map_%s' is too long\n",
-			   map_name, map_name);
+		pr_warn("map:%s length of '____btf_map_%s' is too long\n",
+			map_name, map_name);
 		return -EINVAL;
 	}
 
@@ -769,42 +742,41 @@ int btf__get_map_kv_tids(const struct btf *btf, const char *map_name,
 
 	container_type = btf__type_by_id(btf, container_id);
 	if (!container_type) {
-		pr_warning("map:%s cannot find BTF type for container_id:%u\n",
-			   map_name, container_id);
+		pr_warn("map:%s cannot find BTF type for container_id:%u\n",
+			map_name, container_id);
 		return -EINVAL;
 	}
 
-	if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT ||
-	    BTF_INFO_VLEN(container_type->info) < 2) {
-		pr_warning("map:%s container_name:%s is an invalid container struct\n",
-			   map_name, container_name);
+	if (!btf_is_struct(container_type) || btf_vlen(container_type) < 2) {
+		pr_warn("map:%s container_name:%s is an invalid container struct\n",
+			map_name, container_name);
 		return -EINVAL;
 	}
 
-	key = (struct btf_member *)(container_type + 1);
+	key = btf_members(container_type);
 	value = key + 1;
 
 	key_size = btf__resolve_size(btf, key->type);
 	if (key_size < 0) {
-		pr_warning("map:%s invalid BTF key_type_size\n", map_name);
+		pr_warn("map:%s invalid BTF key_type_size\n", map_name);
 		return key_size;
 	}
 
 	if (expected_key_size != key_size) {
-		pr_warning("map:%s btf_key_type_size:%u != map_def_key_size:%u\n",
-			   map_name, (__u32)key_size, expected_key_size);
+		pr_warn("map:%s btf_key_type_size:%u != map_def_key_size:%u\n",
+			map_name, (__u32)key_size, expected_key_size);
 		return -EINVAL;
 	}
 
 	value_size = btf__resolve_size(btf, value->type);
 	if (value_size < 0) {
-		pr_warning("map:%s invalid BTF value_type_size\n", map_name);
+		pr_warn("map:%s invalid BTF value_type_size\n", map_name);
 		return value_size;
 	}
 
 	if (expected_value_size != value_size) {
-		pr_warning("map:%s btf_value_type_size:%u != map_def_value_size:%u\n",
-			   map_name, (__u32)value_size, expected_value_size);
+		pr_warn("map:%s btf_value_type_size:%u != map_def_value_size:%u\n",
+			map_name, (__u32)value_size, expected_value_size);
 		return -EINVAL;
 	}
 
@@ -831,6 +803,9 @@ static int btf_ext_setup_info(struct btf_ext *btf_ext,
 	/* The start of the info sec (including the __u32 record_size). */
 	void *info;
 
+	if (ext_sec->len == 0)
+		return 0;
+
 	if (ext_sec->off & 0x03) {
 		pr_debug(".BTF.ext %s section is not aligned to 4 bytes\n",
 		     ext_sec->desc);
@@ -934,11 +909,24 @@ static int btf_ext_setup_line_info(struct btf_ext *btf_ext)
 	return btf_ext_setup_info(btf_ext, &param);
 }
 
+static int btf_ext_setup_field_reloc(struct btf_ext *btf_ext)
+{
+	struct btf_ext_sec_setup_param param = {
+		.off = btf_ext->hdr->field_reloc_off,
+		.len = btf_ext->hdr->field_reloc_len,
+		.min_rec_size = sizeof(struct bpf_field_reloc),
+		.ext_info = &btf_ext->field_reloc_info,
+		.desc = "field_reloc",
+	};
+
+	return btf_ext_setup_info(btf_ext, &param);
+}
+
 static int btf_ext_parse_hdr(__u8 *data, __u32 data_size)
 {
 	const struct btf_ext_header *hdr = (struct btf_ext_header *)data;
 
-	if (data_size < offsetof(struct btf_ext_header, func_info_off) ||
+	if (data_size < offsetofend(struct btf_ext_header, hdr_len) ||
 	    data_size < hdr->hdr_len) {
 		pr_debug("BTF.ext header not found");
 		return -EINVAL;
@@ -996,6 +984,9 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size)
 	}
 	memcpy(btf_ext->data, data, size);
 
+	if (btf_ext->hdr->hdr_len <
+	    offsetofend(struct btf_ext_header, line_info_len))
+		goto done;
 	err = btf_ext_setup_func_info(btf_ext);
 	if (err)
 		goto done;
@@ -1004,6 +995,13 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size)
 	if (err)
 		goto done;
 
+	if (btf_ext->hdr->hdr_len <
+	    offsetofend(struct btf_ext_header, field_reloc_len))
+		goto done;
+	err = btf_ext_setup_field_reloc(btf_ext);
+	if (err)
+		goto done;
+
 done:
 	if (err) {
 		btf_ext__free(btf_ext);
@@ -1440,10 +1438,9 @@ static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext,
 	d->map[0] = 0;
 	for (i = 1; i <= btf->nr_types; i++) {
 		struct btf_type *t = d->btf->types[i];
-		__u16 kind = BTF_INFO_KIND(t->info);
 
 		/* VAR and DATASEC are never deduped and are self-canonical */
-		if (kind == BTF_KIND_VAR || kind == BTF_KIND_DATASEC)
+		if (btf_is_var(t) || btf_is_datasec(t))
 			d->map[i] = i;
 		else
 			d->map[i] = BTF_UNPROCESSED_ID;
@@ -1484,11 +1481,11 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx)
 		if (r)
 			return r;
 
-		switch (BTF_INFO_KIND(t->info)) {
+		switch (btf_kind(t)) {
 		case BTF_KIND_STRUCT:
 		case BTF_KIND_UNION: {
-			struct btf_member *m = (struct btf_member *)(t + 1);
-			__u16 vlen = BTF_INFO_VLEN(t->info);
+			struct btf_member *m = btf_members(t);
+			__u16 vlen = btf_vlen(t);
 
 			for (j = 0; j < vlen; j++) {
 				r = fn(&m->name_off, ctx);
@@ -1499,8 +1496,8 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx)
 			break;
 		}
 		case BTF_KIND_ENUM: {
-			struct btf_enum *m = (struct btf_enum *)(t + 1);
-			__u16 vlen = BTF_INFO_VLEN(t->info);
+			struct btf_enum *m = btf_enum(t);
+			__u16 vlen = btf_vlen(t);
 
 			for (j = 0; j < vlen; j++) {
 				r = fn(&m->name_off, ctx);
@@ -1511,8 +1508,8 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx)
 			break;
 		}
 		case BTF_KIND_FUNC_PROTO: {
-			struct btf_param *m = (struct btf_param *)(t + 1);
-			__u16 vlen = BTF_INFO_VLEN(t->info);
+			struct btf_param *m = btf_params(t);
+			__u16 vlen = btf_vlen(t);
 
 			for (j = 0; j < vlen; j++) {
 				r = fn(&m->name_off, ctx);
@@ -1801,16 +1798,16 @@ static long btf_hash_enum(struct btf_type *t)
 /* Check structural equality of two ENUMs. */
 static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2)
 {
-	struct btf_enum *m1, *m2;
+	const struct btf_enum *m1, *m2;
 	__u16 vlen;
 	int i;
 
 	if (!btf_equal_common(t1, t2))
 		return false;
 
-	vlen = BTF_INFO_VLEN(t1->info);
-	m1 = (struct btf_enum *)(t1 + 1);
-	m2 = (struct btf_enum *)(t2 + 1);
+	vlen = btf_vlen(t1);
+	m1 = btf_enum(t1);
+	m2 = btf_enum(t2);
 	for (i = 0; i < vlen; i++) {
 		if (m1->name_off != m2->name_off || m1->val != m2->val)
 			return false;
@@ -1822,8 +1819,7 @@ static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2)
 
 static inline bool btf_is_enum_fwd(struct btf_type *t)
 {
-	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM &&
-	       BTF_INFO_VLEN(t->info) == 0;
+	return btf_is_enum(t) && btf_vlen(t) == 0;
 }
 
 static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
@@ -1843,8 +1839,8 @@ static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2)
  */
 static long btf_hash_struct(struct btf_type *t)
 {
-	struct btf_member *member = (struct btf_member *)(t + 1);
-	__u32 vlen = BTF_INFO_VLEN(t->info);
+	const struct btf_member *member = btf_members(t);
+	__u32 vlen = btf_vlen(t);
 	long h = btf_hash_common(t);
 	int i;
 
@@ -1864,16 +1860,16 @@ static long btf_hash_struct(struct btf_type *t)
  */
 static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2)
 {
-	struct btf_member *m1, *m2;
+	const struct btf_member *m1, *m2;
 	__u16 vlen;
 	int i;
 
 	if (!btf_equal_common(t1, t2))
 		return false;
 
-	vlen = BTF_INFO_VLEN(t1->info);
-	m1 = (struct btf_member *)(t1 + 1);
-	m2 = (struct btf_member *)(t2 + 1);
+	vlen = btf_vlen(t1);
+	m1 = btf_members(t1);
+	m2 = btf_members(t2);
 	for (i = 0; i < vlen; i++) {
 		if (m1->name_off != m2->name_off || m1->offset != m2->offset)
 			return false;
@@ -1890,7 +1886,7 @@ static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2)
  */
 static long btf_hash_array(struct btf_type *t)
 {
-	struct btf_array *info = (struct btf_array *)(t + 1);
+	const struct btf_array *info = btf_array(t);
 	long h = btf_hash_common(t);
 
 	h = hash_combine(h, info->type);
@@ -1908,13 +1904,13 @@ static long btf_hash_array(struct btf_type *t)
  */
 static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2)
 {
-	struct btf_array *info1, *info2;
+	const struct btf_array *info1, *info2;
 
 	if (!btf_equal_common(t1, t2))
 		return false;
 
-	info1 = (struct btf_array *)(t1 + 1);
-	info2 = (struct btf_array *)(t2 + 1);
+	info1 = btf_array(t1);
+	info2 = btf_array(t2);
 	return info1->type == info2->type &&
 	       info1->index_type == info2->index_type &&
 	       info1->nelems == info2->nelems;
@@ -1927,14 +1923,10 @@ static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2)
  */
 static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2)
 {
-	struct btf_array *info1, *info2;
-
 	if (!btf_equal_common(t1, t2))
 		return false;
 
-	info1 = (struct btf_array *)(t1 + 1);
-	info2 = (struct btf_array *)(t2 + 1);
-	return info1->nelems == info2->nelems;
+	return btf_array(t1)->nelems == btf_array(t2)->nelems;
 }
 
 /*
@@ -1944,8 +1936,8 @@ static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2)
  */
 static long btf_hash_fnproto(struct btf_type *t)
 {
-	struct btf_param *member = (struct btf_param *)(t + 1);
-	__u16 vlen = BTF_INFO_VLEN(t->info);
+	const struct btf_param *member = btf_params(t);
+	__u16 vlen = btf_vlen(t);
 	long h = btf_hash_common(t);
 	int i;
 
@@ -1966,16 +1958,16 @@ static long btf_hash_fnproto(struct btf_type *t)
  */
 static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
 {
-	struct btf_param *m1, *m2;
+	const struct btf_param *m1, *m2;
 	__u16 vlen;
 	int i;
 
 	if (!btf_equal_common(t1, t2))
 		return false;
 
-	vlen = BTF_INFO_VLEN(t1->info);
-	m1 = (struct btf_param *)(t1 + 1);
-	m2 = (struct btf_param *)(t2 + 1);
+	vlen = btf_vlen(t1);
+	m1 = btf_params(t1);
+	m2 = btf_params(t2);
 	for (i = 0; i < vlen; i++) {
 		if (m1->name_off != m2->name_off || m1->type != m2->type)
 			return false;
@@ -1992,7 +1984,7 @@ static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2)
  */
 static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
 {
-	struct btf_param *m1, *m2;
+	const struct btf_param *m1, *m2;
 	__u16 vlen;
 	int i;
 
@@ -2000,9 +1992,9 @@ static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2)
 	if (t1->name_off != t2->name_off || t1->info != t2->info)
 		return false;
 
-	vlen = BTF_INFO_VLEN(t1->info);
-	m1 = (struct btf_param *)(t1 + 1);
-	m2 = (struct btf_param *)(t2 + 1);
+	vlen = btf_vlen(t1);
+	m1 = btf_params(t1);
+	m2 = btf_params(t2);
 	for (i = 0; i < vlen; i++) {
 		if (m1->name_off != m2->name_off)
 			return false;
@@ -2028,7 +2020,7 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id)
 	__u32 cand_id;
 	long h;
 
-	switch (BTF_INFO_KIND(t->info)) {
+	switch (btf_kind(t)) {
 	case BTF_KIND_CONST:
 	case BTF_KIND_VOLATILE:
 	case BTF_KIND_RESTRICT:
@@ -2141,13 +2133,13 @@ static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id)
 {
 	__u32 orig_type_id = type_id;
 
-	if (BTF_INFO_KIND(d->btf->types[type_id]->info) != BTF_KIND_FWD)
+	if (!btf_is_fwd(d->btf->types[type_id]))
 		return type_id;
 
 	while (is_type_mapped(d, type_id) && d->map[type_id] != type_id)
 		type_id = d->map[type_id];
 
-	if (BTF_INFO_KIND(d->btf->types[type_id]->info) != BTF_KIND_FWD)
+	if (!btf_is_fwd(d->btf->types[type_id]))
 		return type_id;
 
 	return orig_type_id;
@@ -2156,7 +2148,7 @@ static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id)
 
 static inline __u16 btf_fwd_kind(struct btf_type *t)
 {
-	return BTF_INFO_KFLAG(t->info) ? BTF_KIND_UNION : BTF_KIND_STRUCT;
+	return btf_kflag(t) ? BTF_KIND_UNION : BTF_KIND_STRUCT;
 }
 
 /*
@@ -2277,8 +2269,8 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 
 	cand_type = d->btf->types[cand_id];
 	canon_type = d->btf->types[canon_id];
-	cand_kind = BTF_INFO_KIND(cand_type->info);
-	canon_kind = BTF_INFO_KIND(canon_type->info);
+	cand_kind = btf_kind(cand_type);
+	canon_kind = btf_kind(canon_type);
 
 	if (cand_type->name_off != canon_type->name_off)
 		return 0;
@@ -2327,12 +2319,12 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 		return btf_dedup_is_equiv(d, cand_type->type, canon_type->type);
 
 	case BTF_KIND_ARRAY: {
-		struct btf_array *cand_arr, *canon_arr;
+		const struct btf_array *cand_arr, *canon_arr;
 
 		if (!btf_compat_array(cand_type, canon_type))
 			return 0;
-		cand_arr = (struct btf_array *)(cand_type + 1);
-		canon_arr = (struct btf_array *)(canon_type + 1);
+		cand_arr = btf_array(cand_type);
+		canon_arr = btf_array(canon_type);
 		eq = btf_dedup_is_equiv(d,
 			cand_arr->index_type, canon_arr->index_type);
 		if (eq <= 0)
@@ -2342,14 +2334,14 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 
 	case BTF_KIND_STRUCT:
 	case BTF_KIND_UNION: {
-		struct btf_member *cand_m, *canon_m;
+		const struct btf_member *cand_m, *canon_m;
 		__u16 vlen;
 
 		if (!btf_shallow_equal_struct(cand_type, canon_type))
 			return 0;
-		vlen = BTF_INFO_VLEN(cand_type->info);
-		cand_m = (struct btf_member *)(cand_type + 1);
-		canon_m = (struct btf_member *)(canon_type + 1);
+		vlen = btf_vlen(cand_type);
+		cand_m = btf_members(cand_type);
+		canon_m = btf_members(canon_type);
 		for (i = 0; i < vlen; i++) {
 			eq = btf_dedup_is_equiv(d, cand_m->type, canon_m->type);
 			if (eq <= 0)
@@ -2362,7 +2354,7 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 	}
 
 	case BTF_KIND_FUNC_PROTO: {
-		struct btf_param *cand_p, *canon_p;
+		const struct btf_param *cand_p, *canon_p;
 		__u16 vlen;
 
 		if (!btf_compat_fnproto(cand_type, canon_type))
@@ -2370,9 +2362,9 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 		eq = btf_dedup_is_equiv(d, cand_type->type, canon_type->type);
 		if (eq <= 0)
 			return eq;
-		vlen = BTF_INFO_VLEN(cand_type->info);
-		cand_p = (struct btf_param *)(cand_type + 1);
-		canon_p = (struct btf_param *)(canon_type + 1);
+		vlen = btf_vlen(cand_type);
+		cand_p = btf_params(cand_type);
+		canon_p = btf_params(canon_type);
 		for (i = 0; i < vlen; i++) {
 			eq = btf_dedup_is_equiv(d, cand_p->type, canon_p->type);
 			if (eq <= 0)
@@ -2427,8 +2419,8 @@ static void btf_dedup_merge_hypot_map(struct btf_dedup *d)
 		targ_type_id = d->hypot_map[cand_type_id];
 		t_id = resolve_type_id(d, targ_type_id);
 		c_id = resolve_type_id(d, cand_type_id);
-		t_kind = BTF_INFO_KIND(d->btf->types[t_id]->info);
-		c_kind = BTF_INFO_KIND(d->btf->types[c_id]->info);
+		t_kind = btf_kind(d->btf->types[t_id]);
+		c_kind = btf_kind(d->btf->types[c_id]);
 		/*
 		 * Resolve FWD into STRUCT/UNION.
 		 * It's ok to resolve FWD into STRUCT/UNION that's not yet
@@ -2497,7 +2489,7 @@ static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id)
 		return 0;
 
 	t = d->btf->types[type_id];
-	kind = BTF_INFO_KIND(t->info);
+	kind = btf_kind(t);
 
 	if (kind != BTF_KIND_STRUCT && kind != BTF_KIND_UNION)
 		return 0;
@@ -2592,7 +2584,7 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 	t = d->btf->types[type_id];
 	d->map[type_id] = BTF_IN_PROGRESS_ID;
 
-	switch (BTF_INFO_KIND(t->info)) {
+	switch (btf_kind(t)) {
 	case BTF_KIND_CONST:
 	case BTF_KIND_VOLATILE:
 	case BTF_KIND_RESTRICT:
@@ -2616,7 +2608,7 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 		break;
 
 	case BTF_KIND_ARRAY: {
-		struct btf_array *info = (struct btf_array *)(t + 1);
+		struct btf_array *info = btf_array(t);
 
 		ref_type_id = btf_dedup_ref_type(d, info->type);
 		if (ref_type_id < 0)
@@ -2650,8 +2642,8 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id)
 			return ref_type_id;
 		t->type = ref_type_id;
 
-		vlen = BTF_INFO_VLEN(t->info);
-		param = (struct btf_param *)(t + 1);
+		vlen = btf_vlen(t);
+		param = btf_params(t);
 		for (i = 0; i < vlen; i++) {
 			ref_type_id = btf_dedup_ref_type(d, param->type);
 			if (ref_type_id < 0)
@@ -2791,7 +2783,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
 	struct btf_type *t = d->btf->types[type_id];
 	int i, r;
 
-	switch (BTF_INFO_KIND(t->info)) {
+	switch (btf_kind(t)) {
 	case BTF_KIND_INT:
 	case BTF_KIND_ENUM:
 		break;
@@ -2811,7 +2803,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
 		break;
 
 	case BTF_KIND_ARRAY: {
-		struct btf_array *arr_info = (struct btf_array *)(t + 1);
+		struct btf_array *arr_info = btf_array(t);
 
 		r = btf_dedup_remap_type_id(d, arr_info->type);
 		if (r < 0)
@@ -2826,8 +2818,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
 
 	case BTF_KIND_STRUCT:
 	case BTF_KIND_UNION: {
-		struct btf_member *member = (struct btf_member *)(t + 1);
-		__u16 vlen = BTF_INFO_VLEN(t->info);
+		struct btf_member *member = btf_members(t);
+		__u16 vlen = btf_vlen(t);
 
 		for (i = 0; i < vlen; i++) {
 			r = btf_dedup_remap_type_id(d, member->type);
@@ -2840,8 +2832,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
 	}
 
 	case BTF_KIND_FUNC_PROTO: {
-		struct btf_param *param = (struct btf_param *)(t + 1);
-		__u16 vlen = BTF_INFO_VLEN(t->info);
+		struct btf_param *param = btf_params(t);
+		__u16 vlen = btf_vlen(t);
 
 		r = btf_dedup_remap_type_id(d, t->type);
 		if (r < 0)
@@ -2859,8 +2851,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id)
 	}
 
 	case BTF_KIND_DATASEC: {
-		struct btf_var_secinfo *var = (struct btf_var_secinfo *)(t + 1);
-		__u16 vlen = BTF_INFO_VLEN(t->info);
+		struct btf_var_secinfo *var = btf_var_secinfos(t);
+		__u16 vlen = btf_vlen(t);
 
 		for (i = 0; i < vlen; i++) {
 			r = btf_dedup_remap_type_id(d, var->type);

src/btf.h

@@ -5,6 +5,7 @@
 #define __LIBBPF_BTF_H
 
 #include <stdarg.h>
+#include <linux/btf.h>
 #include <linux/types.h>
 
 #ifdef __cplusplus
@@ -57,6 +58,10 @@ struct btf_ext_header {
 	__u32	func_info_len;
 	__u32	line_info_off;
 	__u32	line_info_len;
+
+	/* optional part of .BTF.ext header */
+	__u32	field_reloc_off;
+	__u32	field_reloc_len;
 };
 
 LIBBPF_API void btf__free(struct btf *btf);
@@ -67,6 +72,8 @@ LIBBPF_API int btf__finalize_data(struct bpf_object *obj, struct btf *btf);
 LIBBPF_API int btf__load(struct btf *btf);
 LIBBPF_API __s32 btf__find_by_name(const struct btf *btf,
 				   const char *type_name);
+LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf,
+					const char *type_name, __u32 kind);
 LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf);
 LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf,
 						  __u32 id);
@@ -120,6 +127,183 @@ LIBBPF_API void btf_dump__free(struct btf_dump *d);
 
 LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
 
+/*
+ * A set of helpers for easier BTF types handling
+ */
+static inline __u16 btf_kind(const struct btf_type *t)
+{
+	return BTF_INFO_KIND(t->info);
+}
+
+static inline __u16 btf_vlen(const struct btf_type *t)
+{
+	return BTF_INFO_VLEN(t->info);
+}
+
+static inline bool btf_kflag(const struct btf_type *t)
+{
+	return BTF_INFO_KFLAG(t->info);
+}
+
+static inline bool btf_is_int(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_INT;
+}
+
+static inline bool btf_is_ptr(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_PTR;
+}
+
+static inline bool btf_is_array(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_ARRAY;
+}
+
+static inline bool btf_is_struct(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_STRUCT;
+}
+
+static inline bool btf_is_union(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_UNION;
+}
+
+static inline bool btf_is_composite(const struct btf_type *t)
+{
+	__u16 kind = btf_kind(t);
+
+	return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
+}
+
+static inline bool btf_is_enum(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_ENUM;
+}
+
+static inline bool btf_is_fwd(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_FWD;
+}
+
+static inline bool btf_is_typedef(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_TYPEDEF;
+}
+
+static inline bool btf_is_volatile(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_VOLATILE;
+}
+
+static inline bool btf_is_const(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_CONST;
+}
+
+static inline bool btf_is_restrict(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_RESTRICT;
+}
+
+static inline bool btf_is_mod(const struct btf_type *t)
+{
+	__u16 kind = btf_kind(t);
+
+	return kind == BTF_KIND_VOLATILE ||
+	       kind == BTF_KIND_CONST ||
+	       kind == BTF_KIND_RESTRICT;
+}
+
+static inline bool btf_is_func(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_FUNC;
+}
+
+static inline bool btf_is_func_proto(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_FUNC_PROTO;
+}
+
+static inline bool btf_is_var(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_VAR;
+}
+
+static inline bool btf_is_datasec(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_DATASEC;
+}
+
+static inline __u8 btf_int_encoding(const struct btf_type *t)
+{
+	return BTF_INT_ENCODING(*(__u32 *)(t + 1));
+}
+
+static inline __u8 btf_int_offset(const struct btf_type *t)
+{
+	return BTF_INT_OFFSET(*(__u32 *)(t + 1));
+}
+
+static inline __u8 btf_int_bits(const struct btf_type *t)
+{
+	return BTF_INT_BITS(*(__u32 *)(t + 1));
+}
+
+static inline struct btf_array *btf_array(const struct btf_type *t)
+{
+	return (struct btf_array *)(t + 1);
+}
+
+static inline struct btf_enum *btf_enum(const struct btf_type *t)
+{
+	return (struct btf_enum *)(t + 1);
+}
+
+static inline struct btf_member *btf_members(const struct btf_type *t)
+{
+	return (struct btf_member *)(t + 1);
+}
+
+/* Get bit offset of a member with specified index. */
+static inline __u32 btf_member_bit_offset(const struct btf_type *t,
+					  __u32 member_idx)
+{
+	const struct btf_member *m = btf_members(t) + member_idx;
+	bool kflag = btf_kflag(t);
+
+	return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
+}
+/*
+ * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
+ * BTF_KIND_UNION. If member is not a bitfield, zero is returned.
+ */
+static inline __u32 btf_member_bitfield_size(const struct btf_type *t,
+					     __u32 member_idx)
+{
+	const struct btf_member *m = btf_members(t) + member_idx;
+	bool kflag = btf_kflag(t);
+
+	return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
+}
+
+static inline struct btf_param *btf_params(const struct btf_type *t)
+{
+	return (struct btf_param *)(t + 1);
+}
+
+static inline struct btf_var *btf_var(const struct btf_type *t)
+{
+	return (struct btf_var *)(t + 1);
+}
+
+static inline struct btf_var_secinfo *
+btf_var_secinfos(const struct btf_type *t)
+{
+	return (struct btf_var_secinfo *)(t + 1);
+}
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif

src/btf_dump.c

@@ -48,6 +48,8 @@ struct btf_dump_type_aux_state {
 	__u8 fwd_emitted: 1;
 	/* whether unique non-duplicate name was already assigned */
 	__u8 name_resolved: 1;
+	/* whether type is referenced from any other type */
+	__u8 referenced: 1;
 };
 
 struct btf_dump {
@@ -100,21 +102,6 @@ static bool str_equal_fn(const void *a, const void *b, void *ctx)
 	return strcmp(a, b) == 0;
 }
 
-static __u16 btf_kind_of(const struct btf_type *t)
-{
-	return BTF_INFO_KIND(t->info);
-}
-
-static __u16 btf_vlen_of(const struct btf_type *t)
-{
-	return BTF_INFO_VLEN(t->info);
-}
-
-static bool btf_kflag_of(const struct btf_type *t)
-{
-	return BTF_INFO_KFLAG(t->info);
-}
-
 static const char *btf_name_of(const struct btf_dump *d, __u32 name_off)
 {
 	return btf__name_by_offset(d->btf, name_off);
@@ -188,6 +175,7 @@ void btf_dump__free(struct btf_dump *d)
 	free(d);
 }
 
+static int btf_dump_mark_referenced(struct btf_dump *d);
 static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr);
 static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id);
 
@@ -228,6 +216,11 @@ int btf_dump__dump_type(struct btf_dump *d, __u32 id)
 		/* VOID is special */
 		d->type_states[0].order_state = ORDERED;
 		d->type_states[0].emit_state = EMITTED;
+
+		/* eagerly determine referenced types for anon enums */
+		err = btf_dump_mark_referenced(d);
+		if (err)
+			return err;
 	}
 
 	d->emit_queue_cnt = 0;
@@ -241,6 +234,79 @@ int btf_dump__dump_type(struct btf_dump *d, __u32 id)
 	return 0;
 }
 
+/*
+ * Mark all types that are referenced from any other type. This is used to
+ * determine top-level anonymous enums that need to be emitted as an
+ * independent type declarations.
+ * Anonymous enums come in two flavors: either embedded in a struct's field
+ * definition, in which case they have to be declared inline as part of field
+ * type declaration; or as a top-level anonymous enum, typically used for
+ * declaring global constants. It's impossible to distinguish between two
+ * without knowning whether given enum type was referenced from other type:
+ * top-level anonymous enum won't be referenced by anything, while embedded
+ * one will.
+ */
+static int btf_dump_mark_referenced(struct btf_dump *d)
+{
+	int i, j, n = btf__get_nr_types(d->btf);
+	const struct btf_type *t;
+	__u16 vlen;
+
+	for (i = 1; i <= n; i++) {
+		t = btf__type_by_id(d->btf, i);
+		vlen = btf_vlen(t);
+
+		switch (btf_kind(t)) {
+		case BTF_KIND_INT:
+		case BTF_KIND_ENUM:
+		case BTF_KIND_FWD:
+			break;
+
+		case BTF_KIND_VOLATILE:
+		case BTF_KIND_CONST:
+		case BTF_KIND_RESTRICT:
+		case BTF_KIND_PTR:
+		case BTF_KIND_TYPEDEF:
+		case BTF_KIND_FUNC:
+		case BTF_KIND_VAR:
+			d->type_states[t->type].referenced = 1;
+			break;
+
+		case BTF_KIND_ARRAY: {
+			const struct btf_array *a = btf_array(t);
+
+			d->type_states[a->index_type].referenced = 1;
+			d->type_states[a->type].referenced = 1;
+			break;
+		}
+		case BTF_KIND_STRUCT:
+		case BTF_KIND_UNION: {
+			const struct btf_member *m = btf_members(t);
+
+			for (j = 0; j < vlen; j++, m++)
+				d->type_states[m->type].referenced = 1;
+			break;
+		}
+		case BTF_KIND_FUNC_PROTO: {
+			const struct btf_param *p = btf_params(t);
+
+			for (j = 0; j < vlen; j++, p++)
+				d->type_states[p->type].referenced = 1;
+			break;
+		}
+		case BTF_KIND_DATASEC: {
+			const struct btf_var_secinfo *v = btf_var_secinfos(t);
+
+			for (j = 0; j < vlen; j++, v++)
+				d->type_states[v->type].referenced = 1;
+			break;
+		}
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
 static int btf_dump_add_emit_queue_id(struct btf_dump *d, __u32 id)
 {
 	__u32 *new_queue;
@@ -349,7 +415,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 	 */
 	struct btf_dump_type_aux_state *tstate = &d->type_states[id];
 	const struct btf_type *t;
-	__u16 kind, vlen;
+	__u16 vlen;
 	int err, i;
 
 	/* return true, letting typedefs know that it's ok to be emitted */
@@ -357,18 +423,16 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 		return 1;
 
 	t = btf__type_by_id(d->btf, id);
-	kind = btf_kind_of(t);
 
 	if (tstate->order_state == ORDERING) {
 		/* type loop, but resolvable through fwd declaration */
-		if ((kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION) &&
-		    through_ptr && t->name_off != 0)
+		if (btf_is_composite(t) && through_ptr && t->name_off != 0)
 			return 0;
-		pr_warning("unsatisfiable type cycle, id:[%u]\n", id);
+		pr_warn("unsatisfiable type cycle, id:[%u]\n", id);
 		return -ELOOP;
 	}
 
-	switch (kind) {
+	switch (btf_kind(t)) {
 	case BTF_KIND_INT:
 		tstate->order_state = ORDERED;
 		return 0;
@@ -378,14 +442,12 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 		tstate->order_state = ORDERED;
 		return err;
 
-	case BTF_KIND_ARRAY: {
-		const struct btf_array *a = (void *)(t + 1);
+	case BTF_KIND_ARRAY:
+		return btf_dump_order_type(d, btf_array(t)->type, through_ptr);
 
-		return btf_dump_order_type(d, a->type, through_ptr);
-	}
 	case BTF_KIND_STRUCT:
 	case BTF_KIND_UNION: {
-		const struct btf_member *m = (void *)(t + 1);
+		const struct btf_member *m = btf_members(t);
 		/*
 		 * struct/union is part of strong link, only if it's embedded
 		 * (so no ptr in a path) or it's anonymous (so has to be
@@ -396,7 +458,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 
 		tstate->order_state = ORDERING;
 
-		vlen = btf_vlen_of(t);
+		vlen = btf_vlen(t);
 		for (i = 0; i < vlen; i++, m++) {
 			err = btf_dump_order_type(d, m->type, false);
 			if (err < 0)
@@ -414,7 +476,12 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 	}
 	case BTF_KIND_ENUM:
 	case BTF_KIND_FWD:
-		if (t->name_off != 0) {
+		/*
+		 * non-anonymous or non-referenced enums are top-level
+		 * declarations and should be emitted. Same logic can be
+		 * applied to FWDs, it won't hurt anyways.
+		 */
+		if (t->name_off != 0 || !tstate->referenced) {
 			err = btf_dump_add_emit_queue_id(d, id);
 			if (err)
 				return err;
@@ -447,7 +514,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 		return btf_dump_order_type(d, t->type, through_ptr);
 
 	case BTF_KIND_FUNC_PROTO: {
-		const struct btf_param *p = (void *)(t + 1);
+		const struct btf_param *p = btf_params(t);
 		bool is_strong;
 
 		err = btf_dump_order_type(d, t->type, through_ptr);
@@ -455,7 +522,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr)
 			return err;
 		is_strong = err > 0;
 
-		vlen = btf_vlen_of(t);
+		vlen = btf_vlen(t);
 		for (i = 0; i < vlen; i++, p++) {
 			err = btf_dump_order_type(d, p->type, through_ptr);
 			if (err < 0)
@@ -553,12 +620,7 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
 		return;
 
 	t = btf__type_by_id(d->btf, id);
-	kind = btf_kind_of(t);
-
-	if (top_level_def && t->name_off == 0) {
-		pr_warning("unexpected nameless definition, id:[%u]\n", id);
-		return;
-	}
+	kind = btf_kind(t);
 
 	if (tstate->emit_state == EMITTING) {
 		if (tstate->fwd_emitted)
@@ -574,8 +636,8 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
 			if (id == cont_id)
 				return;
 			if (t->name_off == 0) {
-				pr_warning("anonymous struct/union loop, id:[%u]\n",
-					   id);
+				pr_warn("anonymous struct/union loop, id:[%u]\n",
+					id);
 				return;
 			}
 			btf_dump_emit_struct_fwd(d, id, t);
@@ -618,12 +680,9 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
 	case BTF_KIND_RESTRICT:
 		btf_dump_emit_type(d, t->type, cont_id);
 		break;
-	case BTF_KIND_ARRAY: {
-		const struct btf_array *a = (void *)(t + 1);
-
-		btf_dump_emit_type(d, a->type, cont_id);
+	case BTF_KIND_ARRAY:
+		btf_dump_emit_type(d, btf_array(t)->type, cont_id);
 		break;
-	}
 	case BTF_KIND_FWD:
 		btf_dump_emit_fwd_def(d, id, t);
 		btf_dump_printf(d, ";\n\n");
@@ -656,8 +715,8 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
 		 * applicable
 		 */
 		if (top_level_def || t->name_off == 0) {
-			const struct btf_member *m = (void *)(t + 1);
-			__u16 vlen = btf_vlen_of(t);
+			const struct btf_member *m = btf_members(t);
+			__u16 vlen = btf_vlen(t);
 			int i, new_cont_id;
 
 			new_cont_id = t->name_off == 0 ? cont_id : id;
@@ -678,8 +737,8 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
 		}
 		break;
 	case BTF_KIND_FUNC_PROTO: {
-		const struct btf_param *p = (void *)(t + 1);
-		__u16 vlen = btf_vlen_of(t);
+		const struct btf_param *p = btf_params(t);
+		__u16 vlen = btf_vlen(t);
 		int i;
 
 		btf_dump_emit_type(d, t->type, cont_id);
@@ -696,7 +755,7 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id)
 static int btf_align_of(const struct btf *btf, __u32 id)
 {
 	const struct btf_type *t = btf__type_by_id(btf, id);
-	__u16 kind = btf_kind_of(t);
+	__u16 kind = btf_kind(t);
 
 	switch (kind) {
 	case BTF_KIND_INT:
@@ -709,15 +768,12 @@ static int btf_align_of(const struct btf *btf, __u32 id)
 	case BTF_KIND_CONST:
 	case BTF_KIND_RESTRICT:
 		return btf_align_of(btf, t->type);
-	case BTF_KIND_ARRAY: {
-		const struct btf_array *a = (void *)(t + 1);
-
-		return btf_align_of(btf, a->type);
-	}
+	case BTF_KIND_ARRAY:
+		return btf_align_of(btf, btf_array(t)->type);
 	case BTF_KIND_STRUCT:
 	case BTF_KIND_UNION: {
-		const struct btf_member *m = (void *)(t + 1);
-		__u16 vlen = btf_vlen_of(t);
+		const struct btf_member *m = btf_members(t);
+		__u16 vlen = btf_vlen(t);
 		int i, align = 1;
 
 		for (i = 0; i < vlen; i++, m++)
@@ -726,7 +782,7 @@ static int btf_align_of(const struct btf *btf, __u32 id)
 		return align;
 	}
 	default:
-		pr_warning("unsupported BTF_KIND:%u\n", btf_kind_of(t));
+		pr_warn("unsupported BTF_KIND:%u\n", btf_kind(t));
 		return 1;
 	}
 }
@@ -737,20 +793,18 @@ static bool btf_is_struct_packed(const struct btf *btf, __u32 id,
 	const struct btf_member *m;
 	int align, i, bit_sz;
 	__u16 vlen;
-	bool kflag;
 
 	align = btf_align_of(btf, id);
 	/* size of a non-packed struct has to be a multiple of its alignment*/
 	if (t->size % align)
 		return true;
 
-	m = (void *)(t + 1);
-	kflag = btf_kflag_of(t);
-	vlen = btf_vlen_of(t);
+	m = btf_members(t);
+	vlen = btf_vlen(t);
 	/* all non-bitfield fields have to be naturally aligned */
 	for (i = 0; i < vlen; i++, m++) {
 		align = btf_align_of(btf, m->type);
-		bit_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
+		bit_sz = btf_member_bitfield_size(t, i);
 		if (bit_sz == 0 && m->offset % (8 * align) != 0)
 			return true;
 	}
@@ -807,7 +861,7 @@ static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id,
 				     const struct btf_type *t)
 {
 	btf_dump_printf(d, "%s %s",
-			btf_kind_of(t) == BTF_KIND_STRUCT ? "struct" : "union",
+			btf_is_struct(t) ? "struct" : "union",
 			btf_dump_type_name(d, id));
 }
 
@@ -816,14 +870,12 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
 				     const struct btf_type *t,
 				     int lvl)
 {
-	const struct btf_member *m = (void *)(t + 1);
-	bool kflag = btf_kflag_of(t), is_struct;
+	const struct btf_member *m = btf_members(t);
+	bool is_struct = btf_is_struct(t);
 	int align, i, packed, off = 0;
-	__u16 vlen = btf_vlen_of(t);
+	__u16 vlen = btf_vlen(t);
 
-	is_struct = btf_kind_of(t) == BTF_KIND_STRUCT;
 	packed = is_struct ? btf_is_struct_packed(d->btf, id, t) : 0;
-	align = packed ? 1 : btf_align_of(d->btf, id);
 
 	btf_dump_printf(d, "%s%s%s {",
 			is_struct ? "struct" : "union",
@@ -835,8 +887,8 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
 		int m_off, m_sz;
 
 		fname = btf_name_of(d, m->name_off);
-		m_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
-		m_off = kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
+		m_sz = btf_member_bitfield_size(t, i);
+		m_off = btf_member_bit_offset(t, i);
 		align = packed ? 1 : btf_align_of(d->btf, m->type);
 
 		btf_dump_emit_bit_padding(d, off, m_off, m_sz, align, lvl + 1);
@@ -853,6 +905,13 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
 		btf_dump_printf(d, ";");
 	}
 
+	/* pad at the end, if necessary */
+	if (is_struct) {
+		align = packed ? 1 : btf_align_of(d->btf, id);
+		btf_dump_emit_bit_padding(d, off, t->size * 8, 0, align,
+					  lvl + 1);
+	}
+
 	if (vlen)
 		btf_dump_printf(d, "\n");
 	btf_dump_printf(d, "%s}", pfx(lvl));
@@ -870,8 +929,8 @@ static void btf_dump_emit_enum_def(struct btf_dump *d, __u32 id,
 				   const struct btf_type *t,
 				   int lvl)
 {
-	const struct btf_enum *v = (void *)(t+1);
-	__u16 vlen = btf_vlen_of(t);
+	const struct btf_enum *v = btf_enum(t);
+	__u16 vlen = btf_vlen(t);
 	const char *name;
 	size_t dup_cnt;
 	int i;
@@ -905,7 +964,7 @@ static void btf_dump_emit_fwd_def(struct btf_dump *d, __u32 id,
 {
 	const char *name = btf_dump_type_name(d, id);
 
-	if (btf_kflag_of(t))
+	if (btf_kflag(t))
 		btf_dump_printf(d, "union %s", name);
 	else
 		btf_dump_printf(d, "struct %s", name);
@@ -916,6 +975,17 @@ static void btf_dump_emit_typedef_def(struct btf_dump *d, __u32 id,
 {
 	const char *name = btf_dump_ident_name(d, id);
 
+	/*
+	 * Old GCC versions are emitting invalid typedef for __gnuc_va_list
+	 * pointing to VOID. This generates warnings from btf_dump() and
+	 * results in uncompilable header file, so we are fixing it up here
+	 * with valid typedef into __builtin_va_list.
+	 */
+	if (t->type == 0 && strcmp(name, "__gnuc_va_list") == 0) {
+		btf_dump_printf(d, "typedef __builtin_va_list __gnuc_va_list");
+		return;
+	}
+
 	btf_dump_printf(d, "typedef ");
 	btf_dump_emit_type_decl(d, t->type, name, lvl);
 }
@@ -987,7 +1057,6 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 	struct id_stack decl_stack;
 	const struct btf_type *t;
 	int err, stack_start;
-	__u16 kind;
 
 	stack_start = d->decl_stack_cnt;
 	for (;;) {
@@ -998,7 +1067,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 			 * chain, restore stack, emit warning, and try to
 			 * proceed nevertheless
 			 */
-			pr_warning("not enough memory for decl stack:%d", err);
+			pr_warn("not enough memory for decl stack:%d", err);
 			d->decl_stack_cnt = stack_start;
 			return;
 		}
@@ -1008,8 +1077,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 			break;
 
 		t = btf__type_by_id(d->btf, id);
-		kind = btf_kind_of(t);
-		switch (kind) {
+		switch (btf_kind(t)) {
 		case BTF_KIND_PTR:
 		case BTF_KIND_VOLATILE:
 		case BTF_KIND_CONST:
@@ -1017,12 +1085,9 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 		case BTF_KIND_FUNC_PROTO:
 			id = t->type;
 			break;
-		case BTF_KIND_ARRAY: {
-			const struct btf_array *a = (void *)(t + 1);
-
-			id = a->type;
+		case BTF_KIND_ARRAY:
+			id = btf_array(t)->type;
 			break;
-		}
 		case BTF_KIND_INT:
 		case BTF_KIND_ENUM:
 		case BTF_KIND_FWD:
@@ -1031,8 +1096,8 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id,
 		case BTF_KIND_TYPEDEF:
 			goto done;
 		default:
-			pr_warning("unexpected type in decl chain, kind:%u, id:[%u]\n",
-				   kind, id);
+			pr_warn("unexpected type in decl chain, kind:%u, id:[%u]\n",
+				btf_kind(t), id);
 			goto done;
 		}
 	}
@@ -1070,7 +1135,7 @@ static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack)
 		id = decl_stack->ids[decl_stack->cnt - 1];
 		t = btf__type_by_id(d->btf, id);
 
-		switch (btf_kind_of(t)) {
+		switch (btf_kind(t)) {
 		case BTF_KIND_VOLATILE:
 			btf_dump_printf(d, "volatile ");
 			break;
@@ -1087,20 +1152,6 @@ static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack)
 	}
 }
 
-static bool btf_is_mod_kind(const struct btf *btf, __u32 id)
-{
-	const struct btf_type *t = btf__type_by_id(btf, id);
-
-	switch (btf_kind_of(t)) {
-	case BTF_KIND_VOLATILE:
-	case BTF_KIND_CONST:
-	case BTF_KIND_RESTRICT:
-		return true;
-	default:
-		return false;
-	}
-}
-
 static void btf_dump_emit_name(const struct btf_dump *d,
 			       const char *name, bool last_was_ptr)
 {
@@ -1139,7 +1190,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 		}
 
 		t = btf__type_by_id(d->btf, id);
-		kind = btf_kind_of(t);
+		kind = btf_kind(t);
 
 		switch (kind) {
 		case BTF_KIND_INT:
@@ -1185,7 +1236,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 			btf_dump_printf(d, " restrict");
 			break;
 		case BTF_KIND_ARRAY: {
-			const struct btf_array *a = (void *)(t + 1);
+			const struct btf_array *a = btf_array(t);
 			const struct btf_type *next_t;
 			__u32 next_id;
 			bool multidim;
@@ -1201,7 +1252,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 			 */
 			while (decls->cnt) {
 				next_id = decls->ids[decls->cnt - 1];
-				if (btf_is_mod_kind(d->btf, next_id))
+				next_t = btf__type_by_id(d->btf, next_id);
+				if (btf_is_mod(next_t))
 					decls->cnt--;
 				else
 					break;
@@ -1213,8 +1265,9 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 				return;
 			}
 
+			next_id = decls->ids[decls->cnt - 1];
 			next_t = btf__type_by_id(d->btf, next_id);
-			multidim = btf_kind_of(next_t) == BTF_KIND_ARRAY;
+			multidim = btf_is_array(next_t);
 			/* we need space if we have named non-pointer */
 			if (fname[0] && !last_was_ptr)
 				btf_dump_printf(d, " ");
@@ -1228,8 +1281,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 			return;
 		}
 		case BTF_KIND_FUNC_PROTO: {
-			const struct btf_param *p = (void *)(t + 1);
-			__u16 vlen = btf_vlen_of(t);
+			const struct btf_param *p = btf_params(t);
+			__u16 vlen = btf_vlen(t);
 			int i;
 
 			btf_dump_emit_mods(d, decls);
@@ -1270,8 +1323,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d,
 			return;
 		}
 		default:
-			pr_warning("unexpected type in decl chain, kind:%u, id:[%u]\n",
-				   kind, id);
+			pr_warn("unexpected type in decl chain, kind:%u, id:[%u]\n",
+				kind, id);
 			return;
 		}
 

src/hashmap.h

@@ -10,6 +10,11 @@
 
 #include <stdbool.h>
 #include <stddef.h>
+#ifdef __GLIBC__
+#include <bits/wordsize.h>
+#else
+#include <bits/reg.h>
+#endif
 #include "libbpf_internal.h"
 
 static inline size_t hash_bits(size_t h, int bits)

src/libbpf.h

@@ -57,7 +57,7 @@ enum libbpf_print_level {
 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
 				 const char *, va_list ap);
 
-LIBBPF_API void libbpf_set_print(libbpf_print_fn_t fn);
+LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
 
 /* Hide internal to user */
 struct bpf_object;
@@ -67,18 +67,80 @@ struct bpf_object_open_attr {
 	enum bpf_prog_type prog_type;
 };
 
+/* Helper macro to declare and initialize libbpf options struct
+ *
+ * This dance with uninitialized declaration, followed by memset to zero,
+ * followed by assignment using compound literal syntax is done to preserve
+ * ability to use a nice struct field initialization syntax and **hopefully**
+ * have all the padding bytes initialized to zero. It's not guaranteed though,
+ * when copying literal, that compiler won't copy garbage in literal's padding
+ * bytes, but that's the best way I've found and it seems to work in practice.
+ *
+ * Macro declares opts struct of given type and name, zero-initializes,
+ * including any extra padding, it with memset() and then assigns initial
+ * values provided by users in struct initializer-syntax as varargs.
+ */
+#define DECLARE_LIBBPF_OPTS(TYPE, NAME, ...)				    \
+	struct TYPE NAME = ({ 						    \
+		memset(&NAME, 0, sizeof(struct TYPE));			    \
+		(struct TYPE) {						    \
+			.sz = sizeof(struct TYPE),			    \
+			__VA_ARGS__					    \
+		};							    \
+	})
+
+struct bpf_object_open_opts {
+	/* size of this struct, for forward/backward compatiblity */
+	size_t sz;
+	/* object name override, if provided:
+	 * - for object open from file, this will override setting object
+	 *   name from file path's base name;
+	 * - for object open from memory buffer, this will specify an object
+	 *   name and will override default "<addr>-<buf-size>" name;
+	 */
+	const char *object_name;
+	/* parse map definitions non-strictly, allowing extra attributes/data */
+	bool relaxed_maps;
+	/* process CO-RE relocations non-strictly, allowing them to fail */
+	bool relaxed_core_relocs;
+	/* maps that set the 'pinning' attribute in their definition will have
+	 * their pin_path attribute set to a file in this directory, and be
+	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
+	 */
+	const char *pin_root_path;
+	__u32 attach_prog_fd;
+};
+#define bpf_object_open_opts__last_field attach_prog_fd
+
 LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
 LIBBPF_API struct bpf_object *
+bpf_object__open_file(const char *path, struct bpf_object_open_opts *opts);
+LIBBPF_API struct bpf_object *
+bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
+		     struct bpf_object_open_opts *opts);
+
+/* deprecated bpf_object__open variants */
+LIBBPF_API struct bpf_object *
+bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
+			const char *name);
+LIBBPF_API struct bpf_object *
 bpf_object__open_xattr(struct bpf_object_open_attr *attr);
-struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr,
-					    int flags);
-LIBBPF_API struct bpf_object *bpf_object__open_buffer(void *obj_buf,
-						      size_t obj_buf_sz,
-						      const char *name);
+
 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,
 				__u32 *off);
+
+enum libbpf_pin_type {
+	LIBBPF_PIN_NONE,
+	/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
+	LIBBPF_PIN_BY_NAME,
+};
+
+/* pin_maps and unpin_maps can both be called with a NULL path, in which case
+ * they will use the pin_path attribute of each map (and ignore all maps that
+ * don't have a pin_path set).
+ */
 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
 				      const char *path);
@@ -92,6 +154,7 @@ LIBBPF_API void bpf_object__close(struct bpf_object *object);
 struct bpf_object_load_attr {
 	struct bpf_object *obj;
 	int log_level;
+	const char *target_btf_path;
 };
 
 /* Load/unload object into/from kernel */
@@ -126,6 +189,8 @@ libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
 			 enum bpf_attach_type *expected_attach_type);
 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
 					  enum bpf_attach_type *attach_type);
+LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
+					  enum bpf_attach_type attach_type);
 
 /* Accessors of bpf_program */
 struct bpf_program;
@@ -152,6 +217,9 @@ LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
 LIBBPF_API const char *bpf_program__title(const struct bpf_program *prog,
 					  bool needs_copy);
 
+/* returns program size in bytes */
+LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
+
 LIBBPF_API int bpf_program__load(struct bpf_program *prog, char *license,
 				 __u32 kern_version);
 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
@@ -186,6 +254,8 @@ LIBBPF_API struct bpf_link *
 bpf_program__attach_raw_tracepoint(struct bpf_program *prog,
 				   const char *tp_name);
 
+LIBBPF_API struct bpf_link *
+bpf_program__attach_trace(struct bpf_program *prog);
 struct bpf_insn;
 
 /*
@@ -261,8 +331,14 @@ LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
+LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
+
+LIBBPF_API enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog);
 LIBBPF_API void bpf_program__set_type(struct bpf_program *prog,
 				      enum bpf_prog_type type);
+
+LIBBPF_API enum bpf_attach_type
+bpf_program__get_expected_attach_type(struct bpf_program *prog);
 LIBBPF_API void
 bpf_program__set_expected_attach_type(struct bpf_program *prog,
 				      enum bpf_attach_type type);
@@ -275,6 +351,7 @@ LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
+LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
 
 /*
  * No need for __attribute__((packed)), all members of 'bpf_map_def'
@@ -334,6 +411,9 @@ LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
 LIBBPF_API void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
+LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
+LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map);
+LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
 
@@ -355,8 +435,18 @@ LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
 LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
 			     struct bpf_object **pobj, int *prog_fd);
 
+struct xdp_link_info {
+	__u32 prog_id;
+	__u32 drv_prog_id;
+	__u32 hw_prog_id;
+	__u32 skb_prog_id;
+	__u8 attach_mode;
+};
+
 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
+LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
+				     size_t info_size, __u32 flags);
 
 struct perf_buffer;
 

src/libbpf.map

@@ -183,4 +183,28 @@ LIBBPF_0.0.4 {
 		perf_buffer__new;
 		perf_buffer__new_raw;
 		perf_buffer__poll;
+		xsk_umem__create;
 } LIBBPF_0.0.3;
+
+LIBBPF_0.0.5 {
+	global:
+		bpf_btf_get_next_id;
+} LIBBPF_0.0.4;
+
+LIBBPF_0.0.6 {
+	global:
+		bpf_get_link_xdp_info;
+		bpf_map__get_pin_path;
+		bpf_map__is_pinned;
+		bpf_map__set_pin_path;
+		bpf_object__open_file;
+		bpf_object__open_mem;
+		bpf_program__attach_trace;
+		bpf_program__get_expected_attach_type;
+		bpf_program__get_type;
+		bpf_program__is_tracing;
+		bpf_program__set_tracing;
+		bpf_program__size;
+		btf__find_by_name_kind;
+		libbpf_find_vmlinux_btf_id;
+} LIBBPF_0.0.5;

src/libbpf_internal.h

@@ -29,6 +29,26 @@
 #ifndef max
 # define max(x, y) ((x) < (y) ? (y) : (x))
 #endif
+#ifndef offsetofend
+# define offsetofend(TYPE, FIELD) \
+	(offsetof(TYPE, FIELD) + sizeof(((TYPE *)0)->FIELD))
+#endif
+
+/* Symbol versioning is different between static and shared library.
+ * Properly versioned symbols are needed for shared library, but
+ * only the symbol of the new version is needed for static library.
+ */
+#ifdef SHARED
+# define COMPAT_VERSION(internal_name, api_name, version) \
+	asm(".symver " #internal_name "," #api_name "@" #version);
+# define DEFAULT_VERSION(internal_name, api_name, version) \
+	asm(".symver " #internal_name "," #api_name "@@" #version);
+#else
+# define COMPAT_VERSION(internal_name, api_name, version)
+# define DEFAULT_VERSION(internal_name, api_name, version) \
+	extern typeof(internal_name) api_name \
+	__attribute__((alias(#internal_name)));
+#endif
 
 extern void libbpf_print(enum libbpf_print_level level,
 			 const char *format, ...)
@@ -39,11 +59,159 @@ do {				\
 	libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__);	\
 } while (0)
 
-#define pr_warning(fmt, ...)	__pr(LIBBPF_WARN, fmt, ##__VA_ARGS__)
+#define pr_warn(fmt, ...)	__pr(LIBBPF_WARN, fmt, ##__VA_ARGS__)
 #define pr_info(fmt, ...)	__pr(LIBBPF_INFO, fmt, ##__VA_ARGS__)
 #define pr_debug(fmt, ...)	__pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__)
 
+static inline bool libbpf_validate_opts(const char *opts,
+					size_t opts_sz, size_t user_sz,
+					const char *type_name)
+{
+	if (user_sz < sizeof(size_t)) {
+		pr_warn("%s size (%zu) is too small\n", type_name, user_sz);
+		return false;
+	}
+	if (user_sz > opts_sz) {
+		size_t i;
+
+		for (i = opts_sz; i < user_sz; i++) {
+			if (opts[i]) {
+				pr_warn("%s has non-zero extra bytes",
+					type_name);
+				return false;
+			}
+		}
+	}
+	return true;
+}
+
+#define OPTS_VALID(opts, type)						      \
+	(!(opts) || libbpf_validate_opts((const char *)opts,		      \
+					 offsetofend(struct type,	      \
+						     type##__last_field),     \
+					 (opts)->sz, #type))
+#define OPTS_HAS(opts, field) \
+	((opts) && opts->sz >= offsetofend(typeof(*(opts)), field))
+#define OPTS_GET(opts, field, fallback_value) \
+	(OPTS_HAS(opts, field) ? (opts)->field : fallback_value)
+
 int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
 			 const char *str_sec, size_t str_len);
 
+struct btf_ext_info {
+	/*
+	 * info points to the individual info section (e.g. func_info and
+	 * line_info) from the .BTF.ext. It does not include the __u32 rec_size.
+	 */
+	void *info;
+	__u32 rec_size;
+	__u32 len;
+};
+
+#define for_each_btf_ext_sec(seg, sec)					\
+	for (sec = (seg)->info;						\
+	     (void *)sec < (seg)->info + (seg)->len;			\
+	     sec = (void *)sec + sizeof(struct btf_ext_info_sec) +	\
+		   (seg)->rec_size * sec->num_info)
+
+#define for_each_btf_ext_rec(seg, sec, i, rec)				\
+	for (i = 0, rec = (void *)&(sec)->data;				\
+	     i < (sec)->num_info;					\
+	     i++, rec = (void *)rec + (seg)->rec_size)
+
+struct btf_ext {
+	union {
+		struct btf_ext_header *hdr;
+		void *data;
+	};
+	struct btf_ext_info func_info;
+	struct btf_ext_info line_info;
+	struct btf_ext_info field_reloc_info;
+	__u32 data_size;
+};
+
+struct btf_ext_info_sec {
+	__u32	sec_name_off;
+	__u32	num_info;
+	/* Followed by num_info * record_size number of bytes */
+	__u8	data[0];
+};
+
+/* The minimum bpf_func_info checked by the loader */
+struct bpf_func_info_min {
+	__u32   insn_off;
+	__u32   type_id;
+};
+
+/* The minimum bpf_line_info checked by the loader */
+struct bpf_line_info_min {
+	__u32	insn_off;
+	__u32	file_name_off;
+	__u32	line_off;
+	__u32	line_col;
+};
+
+/* bpf_field_info_kind encodes which aspect of captured field has to be
+ * adjusted by relocations. Currently supported values are:
+ *   - BPF_FIELD_BYTE_OFFSET: field offset (in bytes);
+ *   - BPF_FIELD_EXISTS: field existence (1, if field exists; 0, otherwise);
+ */
+enum bpf_field_info_kind {
+	BPF_FIELD_BYTE_OFFSET = 0,	/* field byte offset */
+	BPF_FIELD_BYTE_SIZE = 1,
+	BPF_FIELD_EXISTS = 2,		/* field existence in target kernel */
+	BPF_FIELD_SIGNED = 3,
+	BPF_FIELD_LSHIFT_U64 = 4,
+	BPF_FIELD_RSHIFT_U64 = 5,
+};
+
+/* The minimum bpf_field_reloc checked by the loader
+ *
+ * Field relocation captures the following data:
+ * - insn_off - instruction offset (in bytes) within a BPF program that needs
+ *   its insn->imm field to be relocated with actual field info;
+ * - type_id - BTF type ID of the "root" (containing) entity of a relocatable
+ *   field;
+ * - access_str_off - offset into corresponding .BTF string section. String
+ *   itself encodes an accessed field using a sequence of field and array
+ *   indicies, separated by colon (:). It's conceptually very close to LLVM's
+ *   getelementptr ([0]) instruction's arguments for identifying offset to 
+ *   a field.
+ *
+ * Example to provide a better feel.
+ *
+ *   struct sample {
+ *       int a;
+ *       struct {
+ *           int b[10];
+ *       };
+ *   };
+ *
+ *   struct sample *s = ...;
+ *   int x = &s->a;     // encoded as "0:0" (a is field #0)
+ *   int y = &s->b[5];  // encoded as "0:1:0:5" (anon struct is field #1, 
+ *                      // b is field #0 inside anon struct, accessing elem #5)
+ *   int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
+ *
+ * type_id for all relocs in this example  will capture BTF type id of
+ * `struct sample`.
+ *
+ * Such relocation is emitted when using __builtin_preserve_access_index()
+ * Clang built-in, passing expression that captures field address, e.g.:
+ *
+ * bpf_probe_read(&dst, sizeof(dst),
+ *		  __builtin_preserve_access_index(&src->a.b.c));
+ *
+ * In this case Clang will emit field relocation recording necessary data to
+ * be able to find offset of embedded `a.b.c` field within `src` struct.
+ *
+ *   [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction
+ */
+struct bpf_field_reloc {
+	__u32   insn_off;
+	__u32   type_id;
+	__u32   access_str_off;
+	enum bpf_field_info_kind kind;
+};
+
 #endif /* __LIBBPF_LIBBPF_INTERNAL_H */

src/libbpf_probes.c

@@ -102,6 +102,7 @@ probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns,
 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+	case BPF_PROG_TYPE_TRACING:
 	default:
 		break;
 	}
@@ -244,6 +245,7 @@ bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex)
 	case BPF_MAP_TYPE_ARRAY_OF_MAPS:
 	case BPF_MAP_TYPE_HASH_OF_MAPS:
 	case BPF_MAP_TYPE_DEVMAP:
+	case BPF_MAP_TYPE_DEVMAP_HASH:
 	case BPF_MAP_TYPE_SOCKMAP:
 	case BPF_MAP_TYPE_CPUMAP:
 	case BPF_MAP_TYPE_XSKMAP:

src/netlink.c

@@ -12,6 +12,7 @@
 
 #include "bpf.h"
 #include "libbpf.h"
+#include "libbpf_internal.h"
 #include "nlattr.h"
 
 #ifndef SOL_NETLINK
@@ -24,7 +25,7 @@ typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg, libbpf_dump_nlmsg_t,
 struct xdp_id_md {
 	int ifindex;
 	__u32 flags;
-	__u32 id;
+	struct xdp_link_info info;
 };
 
 int libbpf_netlink_open(__u32 *nl_pid)
@@ -43,7 +44,7 @@ int libbpf_netlink_open(__u32 *nl_pid)
 
 	if (setsockopt(sock, SOL_NETLINK, NETLINK_EXT_ACK,
 		       &one, sizeof(one)) < 0) {
-		fprintf(stderr, "Netlink error reporting not supported\n");
+		pr_warn("Netlink error reporting not supported\n");
 	}
 
 	if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
@@ -202,26 +203,11 @@ static int __dump_link_nlmsg(struct nlmsghdr *nlh,
 	return dump_link_nlmsg(cookie, ifi, tb);
 }
 
-static unsigned char get_xdp_id_attr(unsigned char mode, __u32 flags)
-{
-	if (mode != XDP_ATTACHED_MULTI)
-		return IFLA_XDP_PROG_ID;
-	if (flags & XDP_FLAGS_DRV_MODE)
-		return IFLA_XDP_DRV_PROG_ID;
-	if (flags & XDP_FLAGS_HW_MODE)
-		return IFLA_XDP_HW_PROG_ID;
-	if (flags & XDP_FLAGS_SKB_MODE)
-		return IFLA_XDP_SKB_PROG_ID;
-
-	return IFLA_XDP_UNSPEC;
-}
-
-static int get_xdp_id(void *cookie, void *msg, struct nlattr **tb)
+static int get_xdp_info(void *cookie, void *msg, struct nlattr **tb)
 {
 	struct nlattr *xdp_tb[IFLA_XDP_MAX + 1];
 	struct xdp_id_md *xdp_id = cookie;
 	struct ifinfomsg *ifinfo = msg;
-	unsigned char mode, xdp_attr;
 	int ret;
 
 	if (xdp_id->ifindex && xdp_id->ifindex != ifinfo->ifi_index)
@@ -237,27 +223,40 @@ static int get_xdp_id(void *cookie, void *msg, struct nlattr **tb)
 	if (!xdp_tb[IFLA_XDP_ATTACHED])
 		return 0;
 
-	mode = libbpf_nla_getattr_u8(xdp_tb[IFLA_XDP_ATTACHED]);
-	if (mode == XDP_ATTACHED_NONE)
+	xdp_id->info.attach_mode = libbpf_nla_getattr_u8(
+		xdp_tb[IFLA_XDP_ATTACHED]);
+
+	if (xdp_id->info.attach_mode == XDP_ATTACHED_NONE)
 		return 0;
 
-	xdp_attr = get_xdp_id_attr(mode, xdp_id->flags);
-	if (!xdp_attr || !xdp_tb[xdp_attr])
-		return 0;
+	if (xdp_tb[IFLA_XDP_PROG_ID])
+		xdp_id->info.prog_id = libbpf_nla_getattr_u32(
+			xdp_tb[IFLA_XDP_PROG_ID]);
 
-	xdp_id->id = libbpf_nla_getattr_u32(xdp_tb[xdp_attr]);
+	if (xdp_tb[IFLA_XDP_SKB_PROG_ID])
+		xdp_id->info.skb_prog_id = libbpf_nla_getattr_u32(
+			xdp_tb[IFLA_XDP_SKB_PROG_ID]);
+
+	if (xdp_tb[IFLA_XDP_DRV_PROG_ID])
+		xdp_id->info.drv_prog_id = libbpf_nla_getattr_u32(
+			xdp_tb[IFLA_XDP_DRV_PROG_ID]);
+
+	if (xdp_tb[IFLA_XDP_HW_PROG_ID])
+		xdp_id->info.hw_prog_id = libbpf_nla_getattr_u32(
+			xdp_tb[IFLA_XDP_HW_PROG_ID]);
 
 	return 0;
 }
 
-int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags)
+int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
+			  size_t info_size, __u32 flags)
 {
 	struct xdp_id_md xdp_id = {};
 	int sock, ret;
 	__u32 nl_pid;
 	__u32 mask;
 
-	if (flags & ~XDP_FLAGS_MASK)
+	if (flags & ~XDP_FLAGS_MASK || !info_size)
 		return -EINVAL;
 
 	/* Check whether the single {HW,DRV,SKB} mode is set */
@@ -273,14 +272,44 @@ int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags)
 	xdp_id.ifindex = ifindex;
 	xdp_id.flags = flags;
 
-	ret = libbpf_nl_get_link(sock, nl_pid, get_xdp_id, &xdp_id);
-	if (!ret)
-		*prog_id = xdp_id.id;
+	ret = libbpf_nl_get_link(sock, nl_pid, get_xdp_info, &xdp_id);
+	if (!ret) {
+		size_t sz = min(info_size, sizeof(xdp_id.info));
+
+		memcpy(info, &xdp_id.info, sz);
+		memset((void *) info + sz, 0, info_size - sz);
+	}
 
 	close(sock);
 	return ret;
 }
 
+static __u32 get_xdp_id(struct xdp_link_info *info, __u32 flags)
+{
+	if (info->attach_mode != XDP_ATTACHED_MULTI)
+		return info->prog_id;
+	if (flags & XDP_FLAGS_DRV_MODE)
+		return info->drv_prog_id;
+	if (flags & XDP_FLAGS_HW_MODE)
+		return info->hw_prog_id;
+	if (flags & XDP_FLAGS_SKB_MODE)
+		return info->skb_prog_id;
+
+	return 0;
+}
+
+int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags)
+{
+	struct xdp_link_info info;
+	int ret;
+
+	ret = bpf_get_link_xdp_info(ifindex, &info, sizeof(info), flags);
+	if (!ret)
+		*prog_id = get_xdp_id(&info, flags);
+
+	return ret;
+}
+
 int libbpf_nl_get_link(int sock, unsigned int nl_pid,
 		       libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie)
 {

src/nlattr.c

@@ -8,6 +8,7 @@
 
 #include <errno.h>
 #include "nlattr.h"
+#include "libbpf_internal.h"
 #include <linux/rtnetlink.h>
 #include <string.h>
 #include <stdio.h>
@@ -121,8 +122,8 @@ int libbpf_nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head,
 		}
 
 		if (tb[type])
-			fprintf(stderr, "Attribute of type %#x found multiple times in message, "
-				  "previous attribute is being ignored.\n", type);
+			pr_warn("Attribute of type %#x found multiple times in message, "
+				"previous attribute is being ignored.\n", type);
 
 		tb[type] = nla;
 	}
@@ -181,15 +182,14 @@ int libbpf_nla_dump_errormsg(struct nlmsghdr *nlh)
 
 	if (libbpf_nla_parse(tb, NLMSGERR_ATTR_MAX, attr, alen,
 			     extack_policy) != 0) {
-		fprintf(stderr,
-			"Failed to parse extended error attributes\n");
+		pr_warn("Failed to parse extended error attributes\n");
 		return 0;
 	}
 
 	if (tb[NLMSGERR_ATTR_MSG])
 		errmsg = (char *) libbpf_nla_data(tb[NLMSGERR_ATTR_MSG]);
 
-	fprintf(stderr, "Kernel error message: %s\n", errmsg);
+	pr_warn("Kernel error message: %s\n", errmsg);
 
 	return 0;
 }

src/xsk.c

@@ -65,7 +65,6 @@ struct xsk_socket {
 	int xsks_map_fd;
 	__u32 queue_id;
 	char ifname[IFNAMSIZ];
-	bool zc;
 };
 
 struct xsk_nl_info {
@@ -74,22 +73,20 @@ struct xsk_nl_info {
 	int fd;
 };
 
-/* For 32-bit systems, we need to use mmap2 as the offsets are 64-bit.
- * Unfortunately, it is not part of glibc.
- */
-static inline void *xsk_mmap(void *addr, size_t length, int prot, int flags,
-			     int fd, __u64 offset)
-{
-#ifdef __NR_mmap2
-	unsigned int page_shift = __builtin_ffs(getpagesize()) - 1;
-	long ret = syscall(__NR_mmap2, addr, length, prot, flags, fd,
-			   (off_t)(offset >> page_shift));
+/* Up until and including Linux 5.3 */
+struct xdp_ring_offset_v1 {
+	__u64 producer;
+	__u64 consumer;
+	__u64 desc;
+};
 
-	return (void *)ret;
-#else
-	return mmap(addr, length, prot, flags, fd, offset);
-#endif
-}
+/* Up until and including Linux 5.3 */
+struct xdp_mmap_offsets_v1 {
+	struct xdp_ring_offset_v1 rx;
+	struct xdp_ring_offset_v1 tx;
+	struct xdp_ring_offset_v1 fr;
+	struct xdp_ring_offset_v1 cr;
+};
 
 int xsk_umem__fd(const struct xsk_umem *umem)
 {
@@ -116,6 +113,7 @@ static void xsk_set_umem_config(struct xsk_umem_config *cfg,
 		cfg->comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS;
 		cfg->frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE;
 		cfg->frame_headroom = XSK_UMEM__DEFAULT_FRAME_HEADROOM;
+		cfg->flags = XSK_UMEM__DEFAULT_FLAGS;
 		return;
 	}
 
@@ -123,6 +121,7 @@ static void xsk_set_umem_config(struct xsk_umem_config *cfg,
 	cfg->comp_size = usr_cfg->comp_size;
 	cfg->frame_size = usr_cfg->frame_size;
 	cfg->frame_headroom = usr_cfg->frame_headroom;
+	cfg->flags = usr_cfg->flags;
 }
 
 static int xsk_set_xdp_socket_config(struct xsk_socket_config *cfg,
@@ -149,14 +148,66 @@ static int xsk_set_xdp_socket_config(struct xsk_socket_config *cfg,
 	return 0;
 }
 
-int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, __u64 size,
-		     struct xsk_ring_prod *fill, struct xsk_ring_cons *comp,
-		     const struct xsk_umem_config *usr_config)
+static void xsk_mmap_offsets_v1(struct xdp_mmap_offsets *off)
+{
+	struct xdp_mmap_offsets_v1 off_v1;
+
+	/* getsockopt on a kernel <= 5.3 has no flags fields.
+	 * Copy over the offsets to the correct places in the >=5.4 format
+	 * and put the flags where they would have been on that kernel.
+	 */
+	memcpy(&off_v1, off, sizeof(off_v1));
+
+	off->rx.producer = off_v1.rx.producer;
+	off->rx.consumer = off_v1.rx.consumer;
+	off->rx.desc = off_v1.rx.desc;
+	off->rx.flags = off_v1.rx.consumer + sizeof(__u32);
+
+	off->tx.producer = off_v1.tx.producer;
+	off->tx.consumer = off_v1.tx.consumer;
+	off->tx.desc = off_v1.tx.desc;
+	off->tx.flags = off_v1.tx.consumer + sizeof(__u32);
+
+	off->fr.producer = off_v1.fr.producer;
+	off->fr.consumer = off_v1.fr.consumer;
+	off->fr.desc = off_v1.fr.desc;
+	off->fr.flags = off_v1.fr.consumer + sizeof(__u32);
+
+	off->cr.producer = off_v1.cr.producer;
+	off->cr.consumer = off_v1.cr.consumer;
+	off->cr.desc = off_v1.cr.desc;
+	off->cr.flags = off_v1.cr.consumer + sizeof(__u32);
+}
+
+static int xsk_get_mmap_offsets(int fd, struct xdp_mmap_offsets *off)
+{
+	socklen_t optlen;
+	int err;
+
+	optlen = sizeof(*off);
+	err = getsockopt(fd, SOL_XDP, XDP_MMAP_OFFSETS, off, &optlen);
+	if (err)
+		return err;
+
+	if (optlen == sizeof(*off))
+		return 0;
+
+	if (optlen == sizeof(struct xdp_mmap_offsets_v1)) {
+		xsk_mmap_offsets_v1(off);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+int xsk_umem__create_v0_0_4(struct xsk_umem **umem_ptr, void *umem_area,
+			    __u64 size, struct xsk_ring_prod *fill,
+			    struct xsk_ring_cons *comp,
+			    const struct xsk_umem_config *usr_config)
 {
 	struct xdp_mmap_offsets off;
 	struct xdp_umem_reg mr;
 	struct xsk_umem *umem;
-	socklen_t optlen;
 	void *map;
 	int err;
 
@@ -178,10 +229,12 @@ int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, __u64 size,
 	umem->umem_area = umem_area;
 	xsk_set_umem_config(&umem->config, usr_config);
 
+	memset(&mr, 0, sizeof(mr));
 	mr.addr = (uintptr_t)umem_area;
 	mr.len = size;
 	mr.chunk_size = umem->config.frame_size;
 	mr.headroom = umem->config.frame_headroom;
+	mr.flags = umem->config.flags;
 
 	err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_REG, &mr, sizeof(mr));
 	if (err) {
@@ -203,17 +256,15 @@ int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, __u64 size,
 		goto out_socket;
 	}
 
-	optlen = sizeof(off);
-	err = getsockopt(umem->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
+	err = xsk_get_mmap_offsets(umem->fd, &off);
 	if (err) {
 		err = -errno;
 		goto out_socket;
 	}
 
-	map = xsk_mmap(NULL, off.fr.desc +
-		       umem->config.fill_size * sizeof(__u64),
-		       PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
-		       umem->fd, XDP_UMEM_PGOFF_FILL_RING);
+	map = mmap(NULL, off.fr.desc + umem->config.fill_size * sizeof(__u64),
+		   PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, umem->fd,
+		   XDP_UMEM_PGOFF_FILL_RING);
 	if (map == MAP_FAILED) {
 		err = -errno;
 		goto out_socket;
@@ -224,13 +275,13 @@ int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, __u64 size,
 	fill->size = umem->config.fill_size;
 	fill->producer = map + off.fr.producer;
 	fill->consumer = map + off.fr.consumer;
+	fill->flags = map + off.fr.flags;
 	fill->ring = map + off.fr.desc;
 	fill->cached_cons = umem->config.fill_size;
 
-	map = xsk_mmap(NULL,
-		       off.cr.desc + umem->config.comp_size * sizeof(__u64),
-		       PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
-		       umem->fd, XDP_UMEM_PGOFF_COMPLETION_RING);
+	map = mmap(NULL, off.cr.desc + umem->config.comp_size * sizeof(__u64),
+		   PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, umem->fd,
+		   XDP_UMEM_PGOFF_COMPLETION_RING);
 	if (map == MAP_FAILED) {
 		err = -errno;
 		goto out_mmap;
@@ -241,6 +292,7 @@ int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, __u64 size,
 	comp->size = umem->config.comp_size;
 	comp->producer = map + off.cr.producer;
 	comp->consumer = map + off.cr.consumer;
+	comp->flags = map + off.cr.flags;
 	comp->ring = map + off.cr.desc;
 
 	*umem_ptr = umem;
@@ -255,6 +307,29 @@ out_umem_alloc:
 	return err;
 }
 
+struct xsk_umem_config_v1 {
+	__u32 fill_size;
+	__u32 comp_size;
+	__u32 frame_size;
+	__u32 frame_headroom;
+};
+
+int xsk_umem__create_v0_0_2(struct xsk_umem **umem_ptr, void *umem_area,
+			    __u64 size, struct xsk_ring_prod *fill,
+			    struct xsk_ring_cons *comp,
+			    const struct xsk_umem_config *usr_config)
+{
+	struct xsk_umem_config config;
+
+	memcpy(&config, usr_config, sizeof(struct xsk_umem_config_v1));
+	config.flags = 0;
+
+	return xsk_umem__create_v0_0_4(umem_ptr, umem_area, size, fill, comp,
+					&config);
+}
+COMPAT_VERSION(xsk_umem__create_v0_0_2, xsk_umem__create, LIBBPF_0.0.2)
+DEFAULT_VERSION(xsk_umem__create_v0_0_4, xsk_umem__create, LIBBPF_0.0.4)
+
 static int xsk_load_xdp_prog(struct xsk_socket *xsk)
 {
 	static const int log_buf_size = 16 * 1024;
@@ -264,33 +339,55 @@ static int xsk_load_xdp_prog(struct xsk_socket *xsk)
 	/* This is the C-program:
 	 * SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx)
 	 * {
-	 *     int index = ctx->rx_queue_index;
+	 *     int ret, index = ctx->rx_queue_index;
 	 *
 	 *     // A set entry here means that the correspnding queue_id
 	 *     // has an active AF_XDP socket bound to it.
+	 *     ret = bpf_redirect_map(&xsks_map, index, XDP_PASS);
+	 *     if (ret > 0)
+	 *         return ret;
+	 *
+	 *     // Fallback for pre-5.3 kernels, not supporting default
+	 *     // action in the flags parameter.
 	 *     if (bpf_map_lookup_elem(&xsks_map, &index))
 	 *         return bpf_redirect_map(&xsks_map, index, 0);
-	 *
 	 *     return XDP_PASS;
 	 * }
 	 */
 	struct bpf_insn prog[] = {
-		/* r1 = *(u32 *)(r1 + 16) */
-		BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 16),
-		/* *(u32 *)(r10 - 4) = r1 */
-		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_1, -4),
-		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
-		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
+		/* r2 = *(u32 *)(r1 + 16) */
+		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 16),
+		/* *(u32 *)(r10 - 4) = r2 */
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -4),
+		/* r1 = xskmap[] */
 		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
+		/* r3 = XDP_PASS */
+		BPF_MOV64_IMM(BPF_REG_3, 2),
+		/* call bpf_redirect_map */
+		BPF_EMIT_CALL(BPF_FUNC_redirect_map),
+		/* if w0 != 0 goto pc+13 */
+		BPF_JMP32_IMM(BPF_JSGT, BPF_REG_0, 0, 13),
+		/* r2 = r10 */
+		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+		/* r2 += -4 */
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
+		/* r1 = xskmap[] */
+		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
+		/* call bpf_map_lookup_elem */
 		BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+		/* r1 = r0 */
 		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
-		BPF_MOV32_IMM(BPF_REG_0, 2),
-		/* if r1 == 0 goto +5 */
+		/* r0 = XDP_PASS */
+		BPF_MOV64_IMM(BPF_REG_0, 2),
+		/* if r1 == 0 goto pc+5 */
 		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 5),
 		/* r2 = *(u32 *)(r10 - 4) */
-		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
 		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_10, -4),
-		BPF_MOV32_IMM(BPF_REG_3, 0),
+		/* r1 = xskmap[] */
+		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
+		/* r3 = 0 */
+		BPF_MOV64_IMM(BPF_REG_3, 0),
+		/* call bpf_redirect_map */
 		BPF_EMIT_CALL(BPF_FUNC_redirect_map),
 		/* The jumps are to this instruction */
 		BPF_EXIT_INSN(),
@@ -301,7 +398,7 @@ static int xsk_load_xdp_prog(struct xsk_socket *xsk)
 				   "LGPL-2.1 or BSD-2-Clause", 0, log_buf,
 				   log_buf_size);
 	if (prog_fd < 0) {
-		pr_warning("BPF log buffer:\n%s", log_buf);
+		pr_warn("BPF log buffer:\n%s", log_buf);
 		return prog_fd;
 	}
 
@@ -317,17 +414,16 @@ static int xsk_load_xdp_prog(struct xsk_socket *xsk)
 
 static int xsk_get_max_queues(struct xsk_socket *xsk)
 {
-	struct ethtool_channels channels;
-	struct ifreq ifr;
+	struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS };
+	struct ifreq ifr = {};
 	int fd, err, ret;
 
 	fd = socket(AF_INET, SOCK_DGRAM, 0);
 	if (fd < 0)
 		return -errno;
 
-	channels.cmd = ETHTOOL_GCHANNELS;
 	ifr.ifr_data = (void *)&channels;
-	strncpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ - 1);
+	memcpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ - 1);
 	ifr.ifr_name[IFNAMSIZ - 1] = '\0';
 	err = ioctl(fd, SIOCETHTOOL, &ifr);
 	if (err && errno != EOPNOTSUPP) {
@@ -335,13 +431,18 @@ static int xsk_get_max_queues(struct xsk_socket *xsk)
 		goto out;
 	}
 
-	if (channels.max_combined == 0 || errno == EOPNOTSUPP)
+	if (err) {
 		/* If the device says it has no channels, then all traffic
 		 * is sent to a single stream, so max queues = 1.
 		 */
 		ret = 1;
-	else
-		ret = channels.max_combined;
+	} else {
+		/* Take the max of rx, tx, combined. Drivers return
+		 * the number of channels in different ways.
+		 */
+		ret = max(channels.max_rx, channels.max_tx);
+		ret = max(ret, (int)channels.max_combined);
+	}
 
 out:
 	close(fd);
@@ -457,6 +558,8 @@ static int xsk_setup_xdp_prog(struct xsk_socket *xsk)
 		}
 	} else {
 		xsk->prog_fd = bpf_prog_get_fd_by_id(prog_id);
+		if (xsk->prog_fd < 0)
+			return -errno;
 		err = xsk_lookup_bpf_maps(xsk);
 		if (err) {
 			close(xsk->prog_fd);
@@ -464,7 +567,8 @@ static int xsk_setup_xdp_prog(struct xsk_socket *xsk)
 		}
 	}
 
-	err = xsk_set_bpf_maps(xsk);
+	if (xsk->rx)
+		err = xsk_set_bpf_maps(xsk);
 	if (err) {
 		xsk_delete_bpf_maps(xsk);
 		close(xsk->prog_fd);
@@ -482,23 +586,27 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 	void *rx_map = NULL, *tx_map = NULL;
 	struct sockaddr_xdp sxdp = {};
 	struct xdp_mmap_offsets off;
-	struct xdp_options opts;
 	struct xsk_socket *xsk;
-	socklen_t optlen;
 	int err;
 
-	if (!umem || !xsk_ptr || !rx || !tx)
+	if (!umem || !xsk_ptr || !(rx || tx))
 		return -EFAULT;
 
-	if (umem->refcount) {
-		pr_warning("Error: shared umems not supported by libbpf.\n");
-		return -EBUSY;
-	}
-
 	xsk = calloc(1, sizeof(*xsk));
 	if (!xsk)
 		return -ENOMEM;
 
+	err = xsk_set_xdp_socket_config(&xsk->config, usr_config);
+	if (err)
+		goto out_xsk_alloc;
+
+	if (umem->refcount &&
+	    !(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
+		pr_warn("Error: shared umems not supported by libbpf supplied XDP program.\n");
+		err = -EBUSY;
+		goto out_xsk_alloc;
+	}
+
 	if (umem->refcount++ > 0) {
 		xsk->fd = socket(AF_XDP, SOCK_RAW, 0);
 		if (xsk->fd < 0) {
@@ -517,13 +625,9 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 		err = -errno;
 		goto out_socket;
 	}
-	strncpy(xsk->ifname, ifname, IFNAMSIZ - 1);
+	memcpy(xsk->ifname, ifname, IFNAMSIZ - 1);
 	xsk->ifname[IFNAMSIZ - 1] = '\0';
 
-	err = xsk_set_xdp_socket_config(&xsk->config, usr_config);
-	if (err)
-		goto out_socket;
-
 	if (rx) {
 		err = setsockopt(xsk->fd, SOL_XDP, XDP_RX_RING,
 				 &xsk->config.rx_size,
@@ -543,19 +647,17 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 		}
 	}
 
-	optlen = sizeof(off);
-	err = getsockopt(xsk->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
+	err = xsk_get_mmap_offsets(xsk->fd, &off);
 	if (err) {
 		err = -errno;
 		goto out_socket;
 	}
 
 	if (rx) {
-		rx_map = xsk_mmap(NULL, off.rx.desc +
-				  xsk->config.rx_size * sizeof(struct xdp_desc),
-				  PROT_READ | PROT_WRITE,
-				  MAP_SHARED | MAP_POPULATE,
-				  xsk->fd, XDP_PGOFF_RX_RING);
+		rx_map = mmap(NULL, off.rx.desc +
+			      xsk->config.rx_size * sizeof(struct xdp_desc),
+			      PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
+			      xsk->fd, XDP_PGOFF_RX_RING);
 		if (rx_map == MAP_FAILED) {
 			err = -errno;
 			goto out_socket;
@@ -565,16 +667,16 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 		rx->size = xsk->config.rx_size;
 		rx->producer = rx_map + off.rx.producer;
 		rx->consumer = rx_map + off.rx.consumer;
+		rx->flags = rx_map + off.rx.flags;
 		rx->ring = rx_map + off.rx.desc;
 	}
 	xsk->rx = rx;
 
 	if (tx) {
-		tx_map = xsk_mmap(NULL, off.tx.desc +
-				  xsk->config.tx_size * sizeof(struct xdp_desc),
-				  PROT_READ | PROT_WRITE,
-				  MAP_SHARED | MAP_POPULATE,
-				  xsk->fd, XDP_PGOFF_TX_RING);
+		tx_map = mmap(NULL, off.tx.desc +
+			      xsk->config.tx_size * sizeof(struct xdp_desc),
+			      PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
+			      xsk->fd, XDP_PGOFF_TX_RING);
 		if (tx_map == MAP_FAILED) {
 			err = -errno;
 			goto out_mmap_rx;
@@ -584,6 +686,7 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 		tx->size = xsk->config.tx_size;
 		tx->producer = tx_map + off.tx.producer;
 		tx->consumer = tx_map + off.tx.consumer;
+		tx->flags = tx_map + off.tx.flags;
 		tx->ring = tx_map + off.tx.desc;
 		tx->cached_cons = xsk->config.tx_size;
 	}
@@ -592,7 +695,12 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 	sxdp.sxdp_family = PF_XDP;
 	sxdp.sxdp_ifindex = xsk->ifindex;
 	sxdp.sxdp_queue_id = xsk->queue_id;
-	sxdp.sxdp_flags = xsk->config.bind_flags;
+	if (umem->refcount > 1) {
+		sxdp.sxdp_flags = XDP_SHARED_UMEM;
+		sxdp.sxdp_shared_umem_fd = umem->fd;
+	} else {
+		sxdp.sxdp_flags = xsk->config.bind_flags;
+	}
 
 	err = bind(xsk->fd, (struct sockaddr *)&sxdp, sizeof(sxdp));
 	if (err) {
@@ -602,15 +710,6 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
 
 	xsk->prog_fd = -1;
 
-	optlen = sizeof(opts);
-	err = getsockopt(xsk->fd, SOL_XDP, XDP_OPTIONS, &opts, &optlen);
-	if (err) {
-		err = -errno;
-		goto out_mmap_tx;
-	}
-
-	xsk->zc = opts.flags & XDP_OPTIONS_ZEROCOPY;
-
 	if (!(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
 		err = xsk_setup_xdp_prog(xsk);
 		if (err)
@@ -639,7 +738,6 @@ out_xsk_alloc:
 int xsk_umem__delete(struct xsk_umem *umem)
 {
 	struct xdp_mmap_offsets off;
-	socklen_t optlen;
 	int err;
 
 	if (!umem)
@@ -648,8 +746,7 @@ int xsk_umem__delete(struct xsk_umem *umem)
 	if (umem->refcount)
 		return -EBUSY;
 
-	optlen = sizeof(off);
-	err = getsockopt(umem->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
+	err = xsk_get_mmap_offsets(umem->fd, &off);
 	if (!err) {
 		munmap(umem->fill->ring - off.fr.desc,
 		       off.fr.desc + umem->config.fill_size * sizeof(__u64));
@@ -667,7 +764,6 @@ void xsk_socket__delete(struct xsk_socket *xsk)
 {
 	size_t desc_sz = sizeof(struct xdp_desc);
 	struct xdp_mmap_offsets off;
-	socklen_t optlen;
 	int err;
 
 	if (!xsk)
@@ -678,8 +774,7 @@ void xsk_socket__delete(struct xsk_socket *xsk)
 		close(xsk->prog_fd);
 	}
 
-	optlen = sizeof(off);
-	err = getsockopt(xsk->fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen);
+	err = xsk_get_mmap_offsets(xsk->fd, &off);
 	if (!err) {
 		if (xsk->rx) {
 			munmap(xsk->rx->ring - off.rx.desc,

src/xsk.h

@@ -32,6 +32,7 @@ struct name { \
 	__u32 *producer; \
 	__u32 *consumer; \
 	void *ring; \
+	__u32 *flags; \
 }
 
 DEFINE_XSK_RING(xsk_ring_prod);
@@ -76,6 +77,11 @@ xsk_ring_cons__rx_desc(const struct xsk_ring_cons *rx, __u32 idx)
 	return &descs[idx & rx->mask];
 }
 
+static inline int xsk_ring_prod__needs_wakeup(const struct xsk_ring_prod *r)
+{
+	return *r->flags & XDP_RING_NEED_WAKEUP;
+}
+
 static inline __u32 xsk_prod_nb_free(struct xsk_ring_prod *r, __u32 nb)
 {
 	__u32 free_entries = r->cached_cons - r->cached_prod;
@@ -162,6 +168,21 @@ static inline void *xsk_umem__get_data(void *umem_area, __u64 addr)
 	return &((char *)umem_area)[addr];
 }
 
+static inline __u64 xsk_umem__extract_addr(__u64 addr)
+{
+	return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
+}
+
+static inline __u64 xsk_umem__extract_offset(__u64 addr)
+{
+	return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
+}
+
+static inline __u64 xsk_umem__add_offset_to_addr(__u64 addr)
+{
+	return xsk_umem__extract_addr(addr) + xsk_umem__extract_offset(addr);
+}
+
 LIBBPF_API int xsk_umem__fd(const struct xsk_umem *umem);
 LIBBPF_API int xsk_socket__fd(const struct xsk_socket *xsk);
 
@@ -170,12 +191,14 @@ LIBBPF_API int xsk_socket__fd(const struct xsk_socket *xsk);
 #define XSK_UMEM__DEFAULT_FRAME_SHIFT    12 /* 4096 bytes */
 #define XSK_UMEM__DEFAULT_FRAME_SIZE     (1 << XSK_UMEM__DEFAULT_FRAME_SHIFT)
 #define XSK_UMEM__DEFAULT_FRAME_HEADROOM 0
+#define XSK_UMEM__DEFAULT_FLAGS 0
 
 struct xsk_umem_config {
 	__u32 fill_size;
 	__u32 comp_size;
 	__u32 frame_size;
 	__u32 frame_headroom;
+	__u32 flags;
 };
 
 /* Flags for the libbpf_flags field. */
@@ -195,6 +218,16 @@ LIBBPF_API int xsk_umem__create(struct xsk_umem **umem,
 				struct xsk_ring_prod *fill,
 				struct xsk_ring_cons *comp,
 				const struct xsk_umem_config *config);
+LIBBPF_API int xsk_umem__create_v0_0_2(struct xsk_umem **umem,
+				       void *umem_area, __u64 size,
+				       struct xsk_ring_prod *fill,
+				       struct xsk_ring_cons *comp,
+				       const struct xsk_umem_config *config);
+LIBBPF_API int xsk_umem__create_v0_0_4(struct xsk_umem **umem,
+				       void *umem_area, __u64 size,
+				       struct xsk_ring_prod *fill,
+				       struct xsk_ring_cons *comp,
+				       const struct xsk_umem_config *config);
 LIBBPF_API int xsk_socket__create(struct xsk_socket **xsk,
 				  const char *ifname, __u32 queue_id,
 				  struct xsk_umem *umem,

travis-ci/managers/debian.sh

@@ -13,6 +13,10 @@ function info() {
     echo -e "\033[33;1m$1\033[0m"
 }
 
+function error() {
+    echo -e "\033[31;1m$1\033[0m"
+}
+
 function docker_exec() {
     docker exec $ENV_VARS -it $CONT_NAME "$@"
 }
@@ -26,43 +30,43 @@ for phase in "${PHASES[@]}"; do
         SETUP)
             info "Setup phase"
             info "Using Debian $DEBIAN_RELEASE"
-	    docker pull debian:$DEBIAN_RELEASE
+            docker pull debian:$DEBIAN_RELEASE
             info "Starting container $CONT_NAME"
             $DOCKER_RUN -v $REPO_ROOT:/build:rw \
                         -w /build --privileged=true --name $CONT_NAME \
-			-dit --net=host debian:$DEBIAN_RELEASE /bin/bash
+                        -dit --net=host debian:$DEBIAN_RELEASE /bin/bash
             docker_exec bash -c "echo deb-src http://deb.debian.org/debian $DEBIAN_RELEASE main >>/etc/apt/sources.list"
             docker_exec apt-get -y update
             docker_exec apt-get -y build-dep libelf-dev
             docker_exec apt-get -y install libelf-dev
             docker_exec apt-get -y install "${ADDITIONAL_DEPS[@]}"
             ;;
-        RUN|RUN_CLANG|RUN_GCC8)
-            if [[ "$phase" = "RUN_CLANG" ]]; then
+        RUN|RUN_CLANG|RUN_GCC8|RUN_ASAN|RUN_CLANG_ASAN|RUN_GCC8_ASAN)
+            if [[ "$phase" = *"CLANG"* ]]; then
                 ENV_VARS="-e CC=clang -e CXX=clang++"
                 CC="clang"
-            elif [[ "$phase" = "RUN_GCC8" ]]; then
+            elif [[ "$phase" = *"GCC8"* ]]; then
                 ENV_VARS="-e CC=gcc-8 -e CXX=g++-8"
                 CC="gcc-8"
+            else
+                CFLAGS="${CFLAGS} -Wno-stringop-truncation"
             fi
-            docker_exec mkdir build
-            docker_exec ${CC:-cc} --version
-            docker_exec make CFLAGS="${CFLAGS}" -C ./src -B OBJDIR=../build
-            docker_exec rm -rf build
-            ;;
-        RUN_ASAN|RUN_CLANG_ASAN|RUN_GCC8_ASAN)
-            if [[ "$phase" = "RUN_CLANG_ASAN" ]]; then
-                ENV_VARS="-e CC=clang -e CXX=clang++"
-                CC="clang"
-            elif [[ "$phase" = "RUN_GCC8_ASAN" ]]; then
-                ENV_VARS="-e CC=gcc-8 -e CXX=g++-8"
-                CC="gcc-8"
+            if [[ "$phase" = *"ASAN"* ]]; then
+                CFLAGS="${CFLAGS} -fsanitize=address,undefined"
             fi
-            CFLAGS="${CFLAGS} -fsanitize=address,undefined"
-            docker_exec mkdir build
+            docker_exec mkdir build install
             docker_exec ${CC:-cc} --version
+            info "build"
             docker_exec make CFLAGS="${CFLAGS}" -C ./src -B OBJDIR=../build
-            docker_exec rm -rf build
+            info "ldd build/libbpf.so:"
+            docker_exec ldd build/libbpf.so
+            if ! docker_exec ldd build/libbpf.so | grep -q libelf; then
+                error "No reference to libelf.so in libbpf.so!"
+                exit 1
+            fi
+            info "install"
+            docker_exec make -C src OBJDIR=../build DESTDIR=../install install
+            docker_exec rm -rf build install
             ;;
         CLEANUP)
             info "Cleanup phase"

travis-ci/managers/ubuntu.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+set -e
+set -x
+
+RELEASE="bionic"
+
+echo "deb-src http://archive.ubuntu.com/ubuntu/ $RELEASE main restricted universe multiverse" >>/etc/apt/sources.list
+
+apt-get update
+apt-get -y build-dep libelf-dev
+apt-get install -y libelf-dev pkg-config
+
+source "$(dirname $0)/travis_wait.bash"
+
+cd $REPO_ROOT
+
+CFLAGS="-g -O2 -Werror -Wall -fsanitize=address,undefined"
+mkdir build install
+cc --version
+make CFLAGS="${CFLAGS}" -C ./src -B OBJDIR=../build
+ldd build/libbpf.so
+if ! ldd build/libbpf.so | grep -q libelf; then
+    echo "FAIL: No reference to libelf.so in libbpf.so!"
+    exit 1
+fi
+make -C src OBJDIR=../build DESTDIR=../install install
+rm -rf build install

travis-ci/managers/xenial.sh

@@ -1,17 +0,0 @@
-#!/bin/bash
-set -e
-set -x
-
-apt-get update
-apt-get -y build-dep libelf-dev
-apt-get install -y libelf-dev
-
-source "$(dirname $0)/travis_wait.bash"
-
-cd $REPO_ROOT
-
-CFLAGS="-g -O2 -Werror -Wall -fsanitize=address,undefined"
-mkdir build
-cc --version
-make CFLAGS="${CFLAGS}" -C ./src -B OBJDIR=../build
-rm -rf build