libbpf: remove prog_info_linear APIs

Remove prog_info_linear-related APIs previously used by perf.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-8-andrii@kernel.orgSigned-off-by: Alexei Starovoitov <ast@kernel.org>

tools/lib/bpf/libbpf.c

@@ -12509,254 +12509,6 @@ int perf_buffer__consume(struct perf_buffer *pb)
 	return 0;
 }
 
-struct bpf_prog_info_array_desc {
-	int	array_offset;	/* e.g. offset of jited_prog_insns */
-	int	count_offset;	/* e.g. offset of jited_prog_len */
-	int	size_offset;	/* > 0: offset of rec size,
-				 * < 0: fix size of -size_offset
-				 */
-};
-
-static struct bpf_prog_info_array_desc bpf_prog_info_array_desc[] = {
-	[BPF_PROG_INFO_JITED_INSNS] = {
-		offsetof(struct bpf_prog_info, jited_prog_insns),
-		offsetof(struct bpf_prog_info, jited_prog_len),
-		-1,
-	},
-	[BPF_PROG_INFO_XLATED_INSNS] = {
-		offsetof(struct bpf_prog_info, xlated_prog_insns),
-		offsetof(struct bpf_prog_info, xlated_prog_len),
-		-1,
-	},
-	[BPF_PROG_INFO_MAP_IDS] = {
-		offsetof(struct bpf_prog_info, map_ids),
-		offsetof(struct bpf_prog_info, nr_map_ids),
-		-(int)sizeof(__u32),
-	},
-	[BPF_PROG_INFO_JITED_KSYMS] = {
-		offsetof(struct bpf_prog_info, jited_ksyms),
-		offsetof(struct bpf_prog_info, nr_jited_ksyms),
-		-(int)sizeof(__u64),
-	},
-	[BPF_PROG_INFO_JITED_FUNC_LENS] = {
-		offsetof(struct bpf_prog_info, jited_func_lens),
-		offsetof(struct bpf_prog_info, nr_jited_func_lens),
-		-(int)sizeof(__u32),
-	},
-	[BPF_PROG_INFO_FUNC_INFO] = {
-		offsetof(struct bpf_prog_info, func_info),
-		offsetof(struct bpf_prog_info, nr_func_info),
-		offsetof(struct bpf_prog_info, func_info_rec_size),
-	},
-	[BPF_PROG_INFO_LINE_INFO] = {
-		offsetof(struct bpf_prog_info, line_info),
-		offsetof(struct bpf_prog_info, nr_line_info),
-		offsetof(struct bpf_prog_info, line_info_rec_size),
-	},
-	[BPF_PROG_INFO_JITED_LINE_INFO] = {
-		offsetof(struct bpf_prog_info, jited_line_info),
-		offsetof(struct bpf_prog_info, nr_jited_line_info),
-		offsetof(struct bpf_prog_info, jited_line_info_rec_size),
-	},
-	[BPF_PROG_INFO_PROG_TAGS] = {
-		offsetof(struct bpf_prog_info, prog_tags),
-		offsetof(struct bpf_prog_info, nr_prog_tags),
-		-(int)sizeof(__u8) * BPF_TAG_SIZE,
-	},
-
-};
-
-static __u32 bpf_prog_info_read_offset_u32(struct bpf_prog_info *info,
-					   int offset)
-{
-	__u32 *array = (__u32 *)info;
-
-	if (offset >= 0)
-		return array[offset / sizeof(__u32)];
-	return -(int)offset;
-}
-
-static __u64 bpf_prog_info_read_offset_u64(struct bpf_prog_info *info,
-					   int offset)
-{
-	__u64 *array = (__u64 *)info;
-
-	if (offset >= 0)
-		return array[offset / sizeof(__u64)];
-	return -(int)offset;
-}
-
-static void bpf_prog_info_set_offset_u32(struct bpf_prog_info *info, int offset,
-					 __u32 val)
-{
-	__u32 *array = (__u32 *)info;
-
-	if (offset >= 0)
-		array[offset / sizeof(__u32)] = val;
-}
-
-static void bpf_prog_info_set_offset_u64(struct bpf_prog_info *info, int offset,
-					 __u64 val)
-{
-	__u64 *array = (__u64 *)info;
-
-	if (offset >= 0)
-		array[offset / sizeof(__u64)] = val;
-}
-
-struct bpf_prog_info_linear *
-bpf_program__get_prog_info_linear(int fd, __u64 arrays)
-{
-	struct bpf_prog_info_linear *info_linear;
-	struct bpf_prog_info info = {};
-	__u32 info_len = sizeof(info);
-	__u32 data_len = 0;
-	int i, err;
-	void *ptr;
-
-	if (arrays >> BPF_PROG_INFO_LAST_ARRAY)
-		return libbpf_err_ptr(-EINVAL);
-
-	/* step 1: get array dimensions */
-	err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
-	if (err) {
-		pr_debug("can't get prog info: %s", strerror(errno));
-		return libbpf_err_ptr(-EFAULT);
-	}
-
-	/* step 2: calculate total size of all arrays */
-	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
-		bool include_array = (arrays & (1UL << i)) > 0;
-		struct bpf_prog_info_array_desc *desc;
-		__u32 count, size;
-
-		desc = bpf_prog_info_array_desc + i;
-
-		/* kernel is too old to support this field */
-		if (info_len < desc->array_offset + sizeof(__u32) ||
-		    info_len < desc->count_offset + sizeof(__u32) ||
-		    (desc->size_offset > 0 && info_len < desc->size_offset))
-			include_array = false;
-
-		if (!include_array) {
-			arrays &= ~(1UL << i);	/* clear the bit */
-			continue;
-		}
-
-		count = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
-		size  = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
-
-		data_len += count * size;
-	}
-
-	/* step 3: allocate continuous memory */
-	data_len = roundup(data_len, sizeof(__u64));
-	info_linear = malloc(sizeof(struct bpf_prog_info_linear) + data_len);
-	if (!info_linear)
-		return libbpf_err_ptr(-ENOMEM);
-
-	/* step 4: fill data to info_linear->info */
-	info_linear->arrays = arrays;
-	memset(&info_linear->info, 0, sizeof(info));
-	ptr = info_linear->data;
-
-	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
-		struct bpf_prog_info_array_desc *desc;
-		__u32 count, size;
-
-		if ((arrays & (1UL << i)) == 0)
-			continue;
-
-		desc  = bpf_prog_info_array_desc + i;
-		count = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
-		size  = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
-		bpf_prog_info_set_offset_u32(&info_linear->info,
-					     desc->count_offset, count);
-		bpf_prog_info_set_offset_u32(&info_linear->info,
-					     desc->size_offset, size);
-		bpf_prog_info_set_offset_u64(&info_linear->info,
-					     desc->array_offset,
-					     ptr_to_u64(ptr));
-		ptr += count * size;
-	}
-
-	/* step 5: call syscall again to get required arrays */
-	err = bpf_obj_get_info_by_fd(fd, &info_linear->info, &info_len);
-	if (err) {
-		pr_debug("can't get prog info: %s", strerror(errno));
-		free(info_linear);
-		return libbpf_err_ptr(-EFAULT);
-	}
-
-	/* step 6: verify the data */
-	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
-		struct bpf_prog_info_array_desc *desc;
-		__u32 v1, v2;
-
-		if ((arrays & (1UL << i)) == 0)
-			continue;
-
-		desc = bpf_prog_info_array_desc + i;
-		v1 = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
-		v2 = bpf_prog_info_read_offset_u32(&info_linear->info,
-						   desc->count_offset);
-		if (v1 != v2)
-			pr_warn("%s: mismatch in element count\n", __func__);
-
-		v1 = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
-		v2 = bpf_prog_info_read_offset_u32(&info_linear->info,
-						   desc->size_offset);
-		if (v1 != v2)
-			pr_warn("%s: mismatch in rec size\n", __func__);
-	}
-
-	/* step 7: update info_len and data_len */
-	info_linear->info_len = sizeof(struct bpf_prog_info);
-	info_linear->data_len = data_len;
-
-	return info_linear;
-}
-
-void bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear)
-{
-	int i;
-
-	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
-		struct bpf_prog_info_array_desc *desc;
-		__u64 addr, offs;
-
-		if ((info_linear->arrays & (1UL << i)) == 0)
-			continue;
-
-		desc = bpf_prog_info_array_desc + i;
-		addr = bpf_prog_info_read_offset_u64(&info_linear->info,
-						     desc->array_offset);
-		offs = addr - ptr_to_u64(info_linear->data);
-		bpf_prog_info_set_offset_u64(&info_linear->info,
-					     desc->array_offset, offs);
-	}
-}
-
-void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear)
-{
-	int i;
-
-	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
-		struct bpf_prog_info_array_desc *desc;
-		__u64 addr, offs;
-
-		if ((info_linear->arrays & (1UL << i)) == 0)
-			continue;
-
-		desc = bpf_prog_info_array_desc + i;
-		offs = bpf_prog_info_read_offset_u64(&info_linear->info,
-						     desc->array_offset);
-		addr = offs + ptr_to_u64(info_linear->data);
-		bpf_prog_info_set_offset_u64(&info_linear->info,
-					     desc->array_offset, addr);
-	}
-}
-
 int bpf_program__set_attach_target(struct bpf_program *prog,
 				   int attach_prog_fd,
 				   const char *attach_func_name)

tools/lib/bpf/libbpf.h

@@ -1396,72 +1396,6 @@ LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void
 LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type,
 				       enum bpf_func_id helper_id, const void *opts);
 
-/*
- * Get bpf_prog_info in continuous memory
- *
- * struct bpf_prog_info has multiple arrays. The user has option to choose
- * arrays to fetch from kernel. The following APIs provide an uniform way to
- * fetch these data. All arrays in bpf_prog_info are stored in a single
- * continuous memory region. This makes it easy to store the info in a
- * file.
- *
- * Before writing bpf_prog_info_linear to files, it is necessary to
- * translate pointers in bpf_prog_info to offsets. Helper functions
- * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
- * are introduced to switch between pointers and offsets.
- *
- * Examples:
- *   # To fetch map_ids and prog_tags:
- *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
- *           (1UL << BPF_PROG_INFO_PROG_TAGS);
- *   struct bpf_prog_info_linear *info_linear =
- *           bpf_program__get_prog_info_linear(fd, arrays);
- *
- *   # To save data in file
- *   bpf_program__bpil_addr_to_offs(info_linear);
- *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
- *
- *   # To read data from file
- *   read(f, info_linear, <proper_size>);
- *   bpf_program__bpil_offs_to_addr(info_linear);
- */
-enum bpf_prog_info_array {
-	BPF_PROG_INFO_FIRST_ARRAY = 0,
-	BPF_PROG_INFO_JITED_INSNS = 0,
-	BPF_PROG_INFO_XLATED_INSNS,
-	BPF_PROG_INFO_MAP_IDS,
-	BPF_PROG_INFO_JITED_KSYMS,
-	BPF_PROG_INFO_JITED_FUNC_LENS,
-	BPF_PROG_INFO_FUNC_INFO,
-	BPF_PROG_INFO_LINE_INFO,
-	BPF_PROG_INFO_JITED_LINE_INFO,
-	BPF_PROG_INFO_PROG_TAGS,
-	BPF_PROG_INFO_LAST_ARRAY,
-};
-
-struct bpf_prog_info_linear {
-	/* size of struct bpf_prog_info, when the tool is compiled */
-	__u32			info_len;
-	/* total bytes allocated for data, round up to 8 bytes */
-	__u32			data_len;
-	/* which arrays are included in data */
-	__u64			arrays;
-	struct bpf_prog_info	info;
-	__u8			data[];
-};
-
-LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
-LIBBPF_API struct bpf_prog_info_linear *
-bpf_program__get_prog_info_linear(int fd, __u64 arrays);
-
-LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
-LIBBPF_API void
-bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
-
-LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
-LIBBPF_API void
-bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
-
 /**
  * @brief **libbpf_num_possible_cpus()** is a helper function to get the
  * number of possible CPUs that the host kernel supports and expects.

tools/lib/bpf/libbpf.map

@@ -118,9 +118,6 @@ LIBBPF_0.0.2 {
 		btf_ext__free;
 		btf_ext__get_raw_data;
 		btf_ext__new;
-		bpf_program__get_prog_info_linear;
-		bpf_program__bpil_addr_to_offs;
-		bpf_program__bpil_offs_to_addr;
 } LIBBPF_0.0.1;
 
 LIBBPF_0.0.3 {