From 985ead416df39d6fe8e89580cc1db6aa273e0175 Mon Sep 17 00:00:00 2001
From: Andrii Nakryiko <andriin@fb.com>
Date: Fri, 13 Dec 2019 17:43:37 -0800
Subject: bpftool: Add skeleton codegen command

Add `bpftool gen skeleton` command, which takes in compiled BPF .o object file
and dumps a BPF skeleton struct and related code to work with that skeleton.
Skeleton itself is tailored to a specific structure of provided BPF object
file, containing accessors (just plain struct fields) for every map and
program, as well as dedicated space for bpf_links. If BPF program is using
global variables, corresponding structure definitions of compatible memory
layout are emitted as well, making it possible to initialize and subsequently
read/update global variables values using simple and clear C syntax for
accessing fields. This skeleton majorly improves usability of
opening/loading/attaching of BPF object, as well as interacting with it
throughout the lifetime of loaded BPF object.

Generated skeleton struct has the following structure:

struct <object-name> {
	/* used by libbpf's skeleton API */
	struct bpf_object_skeleton *skeleton;
	/* bpf_object for libbpf APIs */
	struct bpf_object *obj;
	struct {
		/* for every defined map in BPF object: */
		struct bpf_map *<map-name>;
	} maps;
	struct {
		/* for every program in BPF object: */
		struct bpf_program *<program-name>;
	} progs;
	struct {
		/* for every program in BPF object: */
		struct bpf_link *<program-name>;
	} links;
	/* for every present global data section: */
	struct <object-name>__<one of bss, data, or rodata> {
		/* memory layout of corresponding data section,
		 * with every defined variable represented as a struct field
		 * with exactly the same type, but without const/volatile
		 * modifiers, e.g.:
		 */
		 int *my_var_1;
		 ...
	} *<one of bss, data, or rodata>;
};

This provides great usability improvements:
- no need to look up maps and programs by name, instead just
  my_obj->maps.my_map or my_obj->progs.my_prog would give necessary
  bpf_map/bpf_program pointers, which user can pass to existing libbpf APIs;
- pre-defined places for bpf_links, which will be automatically populated for
  program types that libbpf knows how to attach automatically (currently
  tracepoints, kprobe/kretprobe, raw tracepoint and tracing programs). On
  tearing down skeleton, all active bpf_links will be destroyed (meaning BPF
  programs will be detached, if they are attached). For cases in which libbpf
  doesn't know how to auto-attach BPF program, user can manually create link
  after loading skeleton and they will be auto-detached on skeleton
  destruction:

	my_obj->links.my_fancy_prog = bpf_program__attach_cgroup_whatever(
		my_obj->progs.my_fancy_prog, <whatever extra param);

- it's extremely easy and convenient to work with global data from userspace
  now. Both for read-only and read/write variables, it's possible to
  pre-initialize them before skeleton is loaded:

	skel = my_obj__open(raw_embed_data);
	my_obj->rodata->my_var = 123;
	my_obj__load(skel); /* 123 will be initialization value for my_var */

  After load, if kernel supports mmap() for BPF arrays, user can still read
  (and write for .bss and .data) variables values, but at that point it will
  be directly mmap()-ed to BPF array, backing global variables. This allows to
  seamlessly exchange data with BPF side. From userspace program's POV, all
  the pointers and memory contents stay the same, but mapped kernel memory
  changes to point to created map.
  If kernel doesn't yet support mmap() for BPF arrays, it's still possible to
  use those data section structs to pre-initialize .bss, .data, and .rodata,
  but after load their pointers will be reset to NULL, allowing user code to
  gracefully handle this condition, if necessary.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191214014341.3442258-14-andriin@fb.com
---
 tools/bpf/bpftool/main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'tools/bpf/bpftool/main.c')

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index 4764581ff9ea..1fe91c558508 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -58,7 +58,7 @@ static int do_help(int argc, char **argv)
 		"       %s batch file FILE\n"
 		"       %s version\n"
 		"\n"
-		"       OBJECT := { prog | map | cgroup | perf | net | feature | btf }\n"
+		"       OBJECT := { prog | map | cgroup | perf | net | feature | btf | gen }\n"
 		"       " HELP_SPEC_OPTIONS "\n"
 		"",
 		bin_name, bin_name, bin_name);
@@ -227,6 +227,7 @@ static const struct cmd cmds[] = {
 	{ "net",	do_net },
 	{ "feature",	do_feature },
 	{ "btf",	do_btf },
+	{ "gen",	do_gen },
 	{ "version",	do_version },
 	{ 0 }
 };
-- 
cgit v1.2.3-70-g09d2


From 229c3b47b794e7257744224b21a95d3d9938d00a Mon Sep 17 00:00:00 2001
From: Toke Høiland-Jørgensen <toke@redhat.com>
Date: Mon, 20 Jan 2020 14:06:46 +0100
Subject: bpftool: Use consistent include paths for libbpf
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fix bpftool to include libbpf header files with the bpf/ prefix, to be
consistent with external users of the library. Also ensure that all
includes of exported libbpf header files (those that are exported on 'make
install' of the library) use bracketed includes instead of quoted.

To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.

Fixes: 6910d7d3867a ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560684.1683545.4765181397974997027.stgit@toke.dk
---
 tools/bpf/bpftool/Documentation/bpftool-gen.rst |  2 +-
 tools/bpf/bpftool/Makefile                      |  2 +-
 tools/bpf/bpftool/btf.c                         |  8 ++++----
 tools/bpf/bpftool/btf_dumper.c                  |  2 +-
 tools/bpf/bpftool/cgroup.c                      |  2 +-
 tools/bpf/bpftool/common.c                      |  4 ++--
 tools/bpf/bpftool/feature.c                     |  4 ++--
 tools/bpf/bpftool/gen.c                         | 10 +++++-----
 tools/bpf/bpftool/jit_disasm.c                  |  2 +-
 tools/bpf/bpftool/main.c                        |  4 ++--
 tools/bpf/bpftool/map.c                         |  4 ++--
 tools/bpf/bpftool/map_perf_ring.c               |  4 ++--
 tools/bpf/bpftool/net.c                         |  8 ++++----
 tools/bpf/bpftool/netlink_dumper.c              |  4 ++--
 tools/bpf/bpftool/perf.c                        |  2 +-
 tools/bpf/bpftool/prog.c                        |  6 +++---
 tools/bpf/bpftool/xlated_dumper.c               |  2 +-
 17 files changed, 35 insertions(+), 35 deletions(-)

(limited to 'tools/bpf/bpftool/main.c')

diff --git a/tools/bpf/bpftool/Documentation/bpftool-gen.rst b/tools/bpf/bpftool/Documentation/bpftool-gen.rst
index 86a87da97d0b..94d91322895a 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-gen.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-gen.rst
@@ -196,7 +196,7 @@ and global variables.
   #define __EXAMPLE_SKEL_H__
 
   #include <stdlib.h>
-  #include <libbpf.h>
+  #include <bpf/libbpf.h>
 
   struct example {
   	struct bpf_object_skeleton *skeleton;
diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index 39bc6f0f4f0b..c4e810335810 100644
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -45,7 +45,7 @@ CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
 	-I$(srctree)/kernel/bpf/ \
 	-I$(srctree)/tools/include \
 	-I$(srctree)/tools/include/uapi \
-	-I$(srctree)/tools/lib/bpf \
+	-I$(srctree)/tools/lib \
 	-I$(srctree)/tools/perf
 CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
 ifneq ($(EXTRA_CFLAGS),)
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index 60c75be0666d..4ba90d81b6a1 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -8,15 +8,15 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <bpf.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/btf.h>
+#include <bpf/libbpf.h>
 #include <linux/btf.h>
 #include <linux/hashtable.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
 
-#include "btf.h"
 #include "json_writer.h"
 #include "main.h"
 
@@ -532,7 +532,7 @@ static int do_dump(int argc, char **argv)
 		if (IS_ERR(btf)) {
 			err = PTR_ERR(btf);
 			btf = NULL;
-			p_err("failed to load BTF from %s: %s", 
+			p_err("failed to load BTF from %s: %s",
 			      *argv, strerror(err));
 			goto done;
 		}
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
index d66131f69689..eb4a142016a0 100644
--- a/tools/bpf/bpftool/btf_dumper.c
+++ b/tools/bpf/bpftool/btf_dumper.c
@@ -8,8 +8,8 @@
 #include <linux/bitops.h>
 #include <linux/btf.h>
 #include <linux/err.h>
+#include <bpf/btf.h>
 
-#include "btf.h"
 #include "json_writer.h"
 #include "main.h"
 
diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c
index 2f017caa678d..62c6a1d7cd18 100644
--- a/tools/bpf/bpftool/cgroup.c
+++ b/tools/bpf/bpftool/cgroup.c
@@ -14,7 +14,7 @@
 #include <sys/types.h>
 #include <unistd.h>
 
-#include <bpf.h>
+#include <bpf/bpf.h>
 
 #include "main.h"
 
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c
index 88264abaa738..b75b8ec5469c 100644
--- a/tools/bpf/bpftool/common.c
+++ b/tools/bpf/bpftool/common.c
@@ -20,8 +20,8 @@
 #include <sys/stat.h>
 #include <sys/vfs.h>
 
-#include <bpf.h>
-#include <libbpf.h> /* libbpf_num_possible_cpus */
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
 
 #include "main.h"
 
diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c
index 94735d968c34..446ba891f1e2 100644
--- a/tools/bpf/bpftool/feature.c
+++ b/tools/bpf/bpftool/feature.c
@@ -12,8 +12,8 @@
 #include <linux/filter.h>
 #include <linux/limits.h>
 
-#include <bpf.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
 #include <zlib.h>
 
 #include "main.h"
diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c
index 7ce09a9a6999..f8113b3646f5 100644
--- a/tools/bpf/bpftool/gen.c
+++ b/tools/bpf/bpftool/gen.c
@@ -12,15 +12,15 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <bpf.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/mman.h>
 #include <unistd.h>
+#include <bpf/btf.h>
 
-#include "btf.h"
-#include "libbpf_internal.h"
+#include "bpf/libbpf_internal.h"
 #include "json_writer.h"
 #include "main.h"
 
@@ -333,7 +333,7 @@ static int do_skeleton(int argc, char **argv)
 		#define %2$s						    \n\
 									    \n\
 		#include <stdlib.h>					    \n\
-		#include <libbpf.h>					    \n\
+		#include <bpf/libbpf.h>					    \n\
 									    \n\
 		struct %1$s {						    \n\
 			struct bpf_object_skeleton *skeleton;		    \n\
diff --git a/tools/bpf/bpftool/jit_disasm.c b/tools/bpf/bpftool/jit_disasm.c
index bfed711258ce..f7f5885aa3ba 100644
--- a/tools/bpf/bpftool/jit_disasm.c
+++ b/tools/bpf/bpftool/jit_disasm.c
@@ -24,7 +24,7 @@
 #include <dis-asm.h>
 #include <sys/stat.h>
 #include <limits.h>
-#include <libbpf.h>
+#include <bpf/libbpf.h>
 
 #include "json_writer.h"
 #include "main.h"
diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index 1fe91c558508..6d41bbfc6459 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -9,8 +9,8 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include <bpf.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
 
 #include "main.h"
 
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 86f8ab0b7e63..e6c85680b34d 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -15,9 +15,9 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 
-#include <bpf.h>
+#include <bpf/bpf.h>
+#include <bpf/btf.h>
 
-#include "btf.h"
 #include "json_writer.h"
 #include "main.h"
 
diff --git a/tools/bpf/bpftool/map_perf_ring.c b/tools/bpf/bpftool/map_perf_ring.c
index 4c5531d1a450..d9b29c17fbb8 100644
--- a/tools/bpf/bpftool/map_perf_ring.c
+++ b/tools/bpf/bpftool/map_perf_ring.c
@@ -6,7 +6,7 @@
  */
 #include <errno.h>
 #include <fcntl.h>
-#include <libbpf.h>
+#include <bpf/libbpf.h>
 #include <poll.h>
 #include <signal.h>
 #include <stdbool.h>
@@ -21,7 +21,7 @@
 #include <sys/mman.h>
 #include <sys/syscall.h>
 
-#include <bpf.h>
+#include <bpf/bpf.h>
 #include <perf-sys.h>
 
 #include "main.h"
diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c
index d93bee298e54..c5e3895b7c8b 100644
--- a/tools/bpf/bpftool/net.c
+++ b/tools/bpf/bpftool/net.c
@@ -7,7 +7,8 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
 #include <net/if.h>
 #include <linux/if.h>
 #include <linux/rtnetlink.h>
@@ -16,9 +17,8 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
-#include <bpf.h>
-#include <nlattr.h>
-#include "libbpf_internal.h"
+#include "bpf/nlattr.h"
+#include "bpf/libbpf_internal.h"
 #include "main.h"
 #include "netlink_dumper.h"
 
diff --git a/tools/bpf/bpftool/netlink_dumper.c b/tools/bpf/bpftool/netlink_dumper.c
index 550a0f537eed..5f65140b003b 100644
--- a/tools/bpf/bpftool/netlink_dumper.c
+++ b/tools/bpf/bpftool/netlink_dumper.c
@@ -3,11 +3,11 @@
 
 #include <stdlib.h>
 #include <string.h>
-#include <libbpf.h>
+#include <bpf/libbpf.h>
 #include <linux/rtnetlink.h>
 #include <linux/tc_act/tc_bpf.h>
 
-#include <nlattr.h>
+#include "bpf/nlattr.h"
 #include "main.h"
 #include "netlink_dumper.h"
 
diff --git a/tools/bpf/bpftool/perf.c b/tools/bpf/bpftool/perf.c
index b2046f33e23f..3341aa14acda 100644
--- a/tools/bpf/bpftool/perf.c
+++ b/tools/bpf/bpftool/perf.c
@@ -13,7 +13,7 @@
 #include <unistd.h>
 #include <ftw.h>
 
-#include <bpf.h>
+#include <bpf/bpf.h>
 
 #include "main.h"
 
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 47a61ac42dc0..a3521deca869 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -17,9 +17,9 @@
 #include <linux/err.h>
 #include <linux/sizes.h>
 
-#include <bpf.h>
-#include <btf.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/btf.h>
+#include <bpf/libbpf.h>
 
 #include "cfg.h"
 #include "main.h"
diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c
index 5b91ee65a080..8608cd68cdd0 100644
--- a/tools/bpf/bpftool/xlated_dumper.c
+++ b/tools/bpf/bpftool/xlated_dumper.c
@@ -7,7 +7,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
-#include <libbpf.h>
+#include <bpf/libbpf.h>
 
 #include "disasm.h"
 #include "json_writer.h"
-- 
cgit v1.2.3-70-g09d2