Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 621 insertions, 0 deletions

diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c
new file mode 100644
index 000000000..4033c46d8
--- /dev/null
+++ b/tools/bpf/bpftool/gen.c
@@ -0,0 +1,621 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2019 Facebook */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/err.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <bpf/btf.h>
+
+#include "json_writer.h"
+#include "main.h"
+
+#define MAX_OBJ_NAME_LEN 64
+
+static void sanitize_identifier(char *name)
+{
+	int i;
+
+	for (i = 0; name[i]; i++)
+		if (!isalnum(name[i]) && name[i] != '_')
+			name[i] = '_';
+}
+
+static bool str_has_suffix(const char *str, const char *suffix)
+{
+	size_t i, n1 = strlen(str), n2 = strlen(suffix);
+
+	if (n1 < n2)
+		return false;
+
+	for (i = 0; i < n2; i++) {
+		if (str[n1 - i - 1] != suffix[n2 - i - 1])
+			return false;
+	}
+
+	return true;
+}
+
+static void get_obj_name(char *name, const char *file)
+{
+	/* Using basename() GNU version which doesn't modify arg. */
+	strncpy(name, basename(file), MAX_OBJ_NAME_LEN - 1);
+	name[MAX_OBJ_NAME_LEN - 1] = '\0';
+	if (str_has_suffix(name, ".o"))
+		name[strlen(name) - 2] = '\0';
+	sanitize_identifier(name);
+}
+
+static void get_header_guard(char *guard, const char *obj_name)
+{
+	int i;
+
+	sprintf(guard, "__%s_SKEL_H__", obj_name);
+	for (i = 0; guard[i]; i++)
+		guard[i] = toupper(guard[i]);
+}
+
+static const char *get_map_ident(const struct bpf_map *map)
+{
+	const char *name = bpf_map__name(map);
+
+	if (!bpf_map__is_internal(map))
+		return name;
+
+	if (str_has_suffix(name, ".data"))
+		return "data";
+	else if (str_has_suffix(name, ".rodata"))
+		return "rodata";
+	else if (str_has_suffix(name, ".bss"))
+		return "bss";
+	else if (str_has_suffix(name, ".kconfig"))
+		return "kconfig";
+	else
+		return NULL;
+}
+
+static void codegen_btf_dump_printf(void *ctx, const char *fmt, va_list args)
+{
+	vprintf(fmt, args);
+}
+
+static int codegen_datasec_def(struct bpf_object *obj,
+			       struct btf *btf,
+			       struct btf_dump *d,
+			       const struct btf_type *sec,
+			       const char *obj_name)
+{
+	const char *sec_name = btf__name_by_offset(btf, sec->name_off);
+	const struct btf_var_secinfo *sec_var = btf_var_secinfos(sec);
+	int i, err, off = 0, pad_cnt = 0, vlen = btf_vlen(sec);
+	const char *sec_ident;
+	char var_ident[256];
+	bool strip_mods = false;
+
+	if (strcmp(sec_name, ".data") == 0) {
+		sec_ident = "data";
+	} else if (strcmp(sec_name, ".bss") == 0) {
+		sec_ident = "bss";
+	} else if (strcmp(sec_name, ".rodata") == 0) {
+		sec_ident = "rodata";
+		strip_mods = true;
+	} else if (strcmp(sec_name, ".kconfig") == 0) {
+		sec_ident = "kconfig";
+	} else {
+		return 0;
+	}
+
+	printf("	struct %s__%s {\n", obj_name, sec_ident);
+	for (i = 0; i < vlen; i++, sec_var++) {
+		const struct btf_type *var = btf__type_by_id(btf, sec_var->type);
+		const char *var_name = btf__name_by_offset(btf, var->name_off);
+		DECLARE_LIBBPF_OPTS(btf_dump_emit_type_decl_opts, opts,
+			.field_name = var_ident,
+			.indent_level = 2,
+			.strip_mods = strip_mods,
+		);
+		int need_off = sec_var->offset, align_off, align;
+		__u32 var_type_id = var->type;
+
+		if (off > need_off) {
+			p_err("Something is wrong for %s's variable #%d: need offset %d, already at %d.\n",
+			      sec_name, i, need_off, off);
+			return -EINVAL;
+		}
+
+		align = btf__align_of(btf, var->type);
+		if (align <= 0) {
+			p_err("Failed to determine alignment of variable '%s': %d",
+			      var_name, align);
+			return -EINVAL;
+		}
+		/* Assume 32-bit architectures when generating data section
+		 * struct memory layout. Given bpftool can't know which target
+		 * host architecture it's emitting skeleton for, we need to be
+		 * conservative and assume 32-bit one to ensure enough padding
+		 * bytes are generated for pointer and long types. This will
+		 * still work correctly for 64-bit architectures, because in
+		 * the worst case we'll generate unnecessary padding field,
+		 * which on 64-bit architectures is not strictly necessary and
+		 * would be handled by natural 8-byte alignment. But it still
+		 * will be a correct memory layout, based on recorded offsets
+		 * in BTF.
+		 */
+		if (align > 4)
+			align = 4;
+
+		align_off = (off + align - 1) / align * align;
+		if (align_off != need_off) {
+			printf("\t\tchar __pad%d[%d];\n",
+			       pad_cnt, need_off - off);
+			pad_cnt++;
+		}
+
+		/* sanitize variable name, e.g., for static vars inside
+		 * a function, it's name is '<function name>.<variable name>',
+		 * which we'll turn into a '<function name>_<variable name>'
+		 */
+		var_ident[0] = '\0';
+		strncat(var_ident, var_name, sizeof(var_ident) - 1);
+		sanitize_identifier(var_ident);
+
+		printf("\t\t");
+		err = btf_dump__emit_type_decl(d, var_type_id, &opts);
+		if (err)
+			return err;
+		printf(";\n");
+
+		off = sec_var->offset + sec_var->size;
+	}
+	printf("	} *%s;\n", sec_ident);
+	return 0;
+}
+
+static int codegen_datasecs(struct bpf_object *obj, const char *obj_name)
+{
+	struct btf *btf = bpf_object__btf(obj);
+	int n = btf__get_nr_types(btf);
+	struct btf_dump *d;
+	int i, err = 0;
+
+	d = btf_dump__new(btf, NULL, NULL, codegen_btf_dump_printf);
+	if (IS_ERR(d))
+		return PTR_ERR(d);
+
+	for (i = 1; i <= n; i++) {
+		const struct btf_type *t = btf__type_by_id(btf, i);
+
+		if (!btf_is_datasec(t))
+			continue;
+
+		err = codegen_datasec_def(obj, btf, d, t, obj_name);
+		if (err)
+			goto out;
+	}
+out:
+	btf_dump__free(d);
+	return err;
+}
+
+static void codegen(const char *template, ...)
+{
+	const char *src, *end;
+	int skip_tabs = 0, n;
+	char *s, *dst;
+	va_list args;
+	char c;
+
+	n = strlen(template);
+	s = malloc(n + 1);
+	if (!s)
+		exit(-1);
+	src = template;
+	dst = s;
+
+	/* find out "baseline" indentation to skip */
+	while ((c = *src++)) {
+		if (c == '\t') {
+			skip_tabs++;
+		} else if (c == '\n') {
+			break;
+		} else {
+			p_err("unrecognized character at pos %td in template '%s'",
+			      src - template - 1, template);
+			free(s);
+			exit(-1);
+		}
+	}
+
+	while (*src) {
+		/* skip baseline indentation tabs */
+		for (n = skip_tabs; n > 0; n--, src++) {
+			if (*src != '\t') {
+				p_err("not enough tabs at pos %td in template '%s'",
+				      src - template - 1, template);
+				free(s);
+				exit(-1);
+			}
+		}
+		/* trim trailing whitespace */
+		end = strchrnul(src, '\n');
+		for (n = end - src; n > 0 && isspace(src[n - 1]); n--)
+			;
+		memcpy(dst, src, n);
+		dst += n;
+		if (*end)
+			*dst++ = '\n';
+		src = *end ? end + 1 : end;
+	}
+	*dst++ = '\0';
+
+	/* print out using adjusted template */
+	va_start(args, template);
+	n = vprintf(s, args);
+	va_end(args);
+
+	free(s);
+}
+
+static int do_skeleton(int argc, char **argv)
+{
+	char header_guard[MAX_OBJ_NAME_LEN + sizeof("__SKEL_H__")];
+	size_t i, map_cnt = 0, prog_cnt = 0, file_sz, mmap_sz;
+	DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts);
+	char obj_name[MAX_OBJ_NAME_LEN], *obj_data;
+	struct bpf_object *obj = NULL;
+	const char *file, *ident;
+	struct bpf_program *prog;
+	int fd, len, err = -1;
+	struct bpf_map *map;
+	struct btf *btf;
+	struct stat st;
+
+	if (!REQ_ARGS(1)) {
+		usage();
+		return -1;
+	}
+	file = GET_ARG();
+
+	if (argc) {
+		p_err("extra unknown arguments");
+		return -1;
+	}
+
+	if (stat(file, &st)) {
+		p_err("failed to stat() %s: %s", file, strerror(errno));
+		return -1;
+	}
+	file_sz = st.st_size;
+	mmap_sz = roundup(file_sz, sysconf(_SC_PAGE_SIZE));
+	fd = open(file, O_RDONLY);
+	if (fd < 0) {
+		p_err("failed to open() %s: %s", file, strerror(errno));
+		return -1;
+	}
+	obj_data = mmap(NULL, mmap_sz, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (obj_data == MAP_FAILED) {
+		obj_data = NULL;
+		p_err("failed to mmap() %s: %s", file, strerror(errno));
+		goto out;
+	}
+	get_obj_name(obj_name, file);
+	opts.object_name = obj_name;
+	obj = bpf_object__open_mem(obj_data, file_sz, &opts);
+	if (IS_ERR(obj)) {
+		char err_buf[256];
+
+		libbpf_strerror(PTR_ERR(obj), err_buf, sizeof(err_buf));
+		p_err("failed to open BPF object file: %s", err_buf);
+		obj = NULL;
+		goto out;
+	}
+
+	bpf_object__for_each_map(map, obj) {
+		ident = get_map_ident(map);
+		if (!ident) {
+			p_err("ignoring unrecognized internal map '%s'...",
+			      bpf_map__name(map));
+			continue;
+		}
+		map_cnt++;
+	}
+	bpf_object__for_each_program(prog, obj) {
+		prog_cnt++;
+	}
+
+	get_header_guard(header_guard, obj_name);
+	codegen("\
+		\n\
+		/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */   \n\
+									    \n\
+		/* THIS FILE IS AUTOGENERATED! */			    \n\
+		#ifndef %2$s						    \n\
+		#define %2$s						    \n\
+									    \n\
+		#include <stdlib.h>					    \n\
+		#include <bpf/libbpf.h>					    \n\
+									    \n\
+		struct %1$s {						    \n\
+			struct bpf_object_skeleton *skeleton;		    \n\
+			struct bpf_object *obj;				    \n\
+		",
+		obj_name, header_guard
+	);
+
+	if (map_cnt) {
+		printf("\tstruct {\n");
+		bpf_object__for_each_map(map, obj) {
+			ident = get_map_ident(map);
+			if (!ident)
+				continue;
+			printf("\t\tstruct bpf_map *%s;\n", ident);
+		}
+		printf("\t} maps;\n");
+	}
+
+	if (prog_cnt) {
+		printf("\tstruct {\n");
+		bpf_object__for_each_program(prog, obj) {
+			printf("\t\tstruct bpf_program *%s;\n",
+			       bpf_program__name(prog));
+		}
+		printf("\t} progs;\n");
+		printf("\tstruct {\n");
+		bpf_object__for_each_program(prog, obj) {
+			printf("\t\tstruct bpf_link *%s;\n",
+			       bpf_program__name(prog));
+		}
+		printf("\t} links;\n");
+	}
+
+	btf = bpf_object__btf(obj);
+	if (btf) {
+		err = codegen_datasecs(obj, obj_name);
+		if (err)
+			goto out;
+	}
+
+	codegen("\
+		\n\
+		};							    \n\
+									    \n\
+		static void						    \n\
+		%1$s__destroy(struct %1$s *obj)				    \n\
+		{							    \n\
+			if (!obj)					    \n\
+				return;					    \n\
+			if (obj->skeleton)				    \n\
+				bpf_object__destroy_skeleton(obj->skeleton);\n\
+			free(obj);					    \n\
+		}							    \n\
+									    \n\
+		static inline int					    \n\
+		%1$s__create_skeleton(struct %1$s *obj);		    \n\
+									    \n\
+		static inline struct %1$s *				    \n\
+		%1$s__open_opts(const struct bpf_object_open_opts *opts)    \n\
+		{							    \n\
+			struct %1$s *obj;				    \n\
+									    \n\
+			obj = (struct %1$s *)calloc(1, sizeof(*obj));	    \n\
+			if (!obj)					    \n\
+				return NULL;				    \n\
+			if (%1$s__create_skeleton(obj))			    \n\
+				goto err;				    \n\
+			if (bpf_object__open_skeleton(obj->skeleton, opts)) \n\
+				goto err;				    \n\
+									    \n\
+			return obj;					    \n\
+		err:							    \n\
+			%1$s__destroy(obj);				    \n\
+			return NULL;					    \n\
+		}							    \n\
+									    \n\
+		static inline struct %1$s *				    \n\
+		%1$s__open(void)					    \n\
+		{							    \n\
+			return %1$s__open_opts(NULL);			    \n\
+		}							    \n\
+									    \n\
+		static inline int					    \n\
+		%1$s__load(struct %1$s *obj)				    \n\
+		{							    \n\
+			return bpf_object__load_skeleton(obj->skeleton);    \n\
+		}							    \n\
+									    \n\
+		static inline struct %1$s *				    \n\
+		%1$s__open_and_load(void)				    \n\
+		{							    \n\
+			struct %1$s *obj;				    \n\
+									    \n\
+			obj = %1$s__open();				    \n\
+			if (!obj)					    \n\
+				return NULL;				    \n\
+			if (%1$s__load(obj)) {				    \n\
+				%1$s__destroy(obj);			    \n\
+				return NULL;				    \n\
+			}						    \n\
+			return obj;					    \n\
+		}							    \n\
+									    \n\
+		static inline int					    \n\
+		%1$s__attach(struct %1$s *obj)				    \n\
+		{							    \n\
+			return bpf_object__attach_skeleton(obj->skeleton);  \n\
+		}							    \n\
+									    \n\
+		static inline void					    \n\
+		%1$s__detach(struct %1$s *obj)				    \n\
+		{							    \n\
+			return bpf_object__detach_skeleton(obj->skeleton);  \n\
+		}							    \n\
+		",
+		obj_name
+	);
+
+	codegen("\
+		\n\
+									    \n\
+		static inline int					    \n\
+		%1$s__create_skeleton(struct %1$s *obj)			    \n\
+		{							    \n\
+			struct bpf_object_skeleton *s;			    \n\
+									    \n\
+			s = (struct bpf_object_skeleton *)calloc(1, sizeof(*s));\n\
+			if (!s)						    \n\
+				return -1;				    \n\
+			obj->skeleton = s;				    \n\
+									    \n\
+			s->sz = sizeof(*s);				    \n\
+			s->name = \"%1$s\";				    \n\
+			s->obj = &obj->obj;				    \n\
+		",
+		obj_name
+	);
+	if (map_cnt) {
+		codegen("\
+			\n\
+									    \n\
+				/* maps */				    \n\
+				s->map_cnt = %zu;			    \n\
+				s->map_skel_sz = sizeof(*s->maps);	    \n\
+				s->maps = (struct bpf_map_skeleton *)calloc(s->map_cnt, s->map_skel_sz);\n\
+				if (!s->maps)				    \n\
+					goto err;			    \n\
+			",
+			map_cnt
+		);
+		i = 0;
+		bpf_object__for_each_map(map, obj) {
+			ident = get_map_ident(map);
+
+			if (!ident)
+				continue;
+
+			codegen("\
+				\n\
+									    \n\
+					s->maps[%zu].name = \"%s\";	    \n\
+					s->maps[%zu].map = &obj->maps.%s;   \n\
+				",
+				i, bpf_map__name(map), i, ident);
+			/* memory-mapped internal maps */
+			if (bpf_map__is_internal(map) &&
+			    (bpf_map__def(map)->map_flags & BPF_F_MMAPABLE)) {
+				printf("\ts->maps[%zu].mmaped = (void **)&obj->%s;\n",
+				       i, ident);
+			}
+			i++;
+		}
+	}
+	if (prog_cnt) {
+		codegen("\
+			\n\
+									    \n\
+				/* programs */				    \n\
+				s->prog_cnt = %zu;			    \n\
+				s->prog_skel_sz = sizeof(*s->progs);	    \n\
+				s->progs = (struct bpf_prog_skeleton *)calloc(s->prog_cnt, s->prog_skel_sz);\n\
+				if (!s->progs)				    \n\
+					goto err;			    \n\
+			",
+			prog_cnt
+		);
+		i = 0;
+		bpf_object__for_each_program(prog, obj) {
+			codegen("\
+				\n\
+									    \n\
+					s->progs[%1$zu].name = \"%2$s\";    \n\
+					s->progs[%1$zu].prog = &obj->progs.%2$s;\n\
+					s->progs[%1$zu].link = &obj->links.%2$s;\n\
+				",
+				i, bpf_program__name(prog));
+			i++;
+		}
+	}
+	codegen("\
+		\n\
+									    \n\
+			s->data_sz = %d;				    \n\
+			s->data = (void *)\"\\				    \n\
+		",
+		file_sz);
+
+	/* embed contents of BPF object file */
+	for (i = 0, len = 0; i < file_sz; i++) {
+		int w = obj_data[i] ? 4 : 2;
+
+		len += w;
+		if (len > 78) {
+			printf("\\\n");
+			len = w;
+		}
+		if (!obj_data[i])
+			printf("\\0");
+		else
+			printf("\\x%02x", (unsigned char)obj_data[i]);
+	}
+
+	codegen("\
+		\n\
+		\";							    \n\
+									    \n\
+			return 0;					    \n\
+		err:							    \n\
+			bpf_object__destroy_skeleton(s);		    \n\
+			return -1;					    \n\
+		}							    \n\
+									    \n\
+		#endif /* %s */						    \n\
+		",
+		header_guard);
+	err = 0;
+out:
+	bpf_object__close(obj);
+	if (obj_data)
+		munmap(obj_data, mmap_sz);
+	close(fd);
+	return err;
+}
+
+static int do_help(int argc, char **argv)
+{
+	if (json_output) {
+		jsonw_null(json_wtr);
+		return 0;
+	}
+
+	fprintf(stderr,
+		"Usage: %1$s %2$s skeleton FILE\n"
+		"       %1$s %2$s help\n"
+		"\n"
+		"       " HELP_SPEC_OPTIONS "\n"
+		"",
+		bin_name, "gen");
+
+	return 0;
+}
+
+static const struct cmd cmds[] = {
+	{ "skeleton",	do_skeleton },
+	{ "help",	do_help },
+	{ 0 }
+};
+
+int do_gen(int argc, char **argv)
+{
+	return cmd_select(cmds, argc, argv, do_help);
+}