tools/bpf/bpf_exp.y

File Facts

System

Linux kernel

Corpus path

tools/bpf/bpf_exp.y

Extension

.y

Size

16098 bytes

Lines

669

Domain

Support Tooling And Documentation

Bucket

tools

Inferred role

Support Tooling And Documentation: tools

Status

atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• stdio.h
• string.h
• stdint.h
• stdlib.h
• stdbool.h
• unistd.h
• errno.h
• assert.h
• linux/filter.h
• bpf_exp.yacc.h

Detected Declarations

• enum jmp_type
• function bpf_assert_max
• function bpf_set_curr_instr
• function bpf_set_curr_label
• function bpf_set_jmp_label
• function bpf_find_insns_offset
• function bpf_stage_1_insert_insns
• function bpf_reduce_k_jumps
• function bpf_encode_jt_jf_offset
• function bpf_reduce_jt_jumps
• function bpf_reduce_jf_jumps
• function bpf_stage_2_reduce_labels
• function bpf_pretty_print_c
• function bpf_pretty_print
• function bpf_init
• function bpf_destroy_labels
• function bpf_destroy
• function bpf_asm_compile
• function yyerror

Annotated Snippet

if ($2 != 4 || $9 != 0xf) {
			fprintf(stderr, "ldxb offset not supported!\n");
			exit(1);
		} else {
			bpf_set_curr_instr(BPF_LDX | BPF_MSH | BPF_B, 0, 0, $6); } }
	| OP_LDX number '*' '(' '[' number ']' '&' number ')' {
		if ($2 != 4 || $9 != 0xf) {
			fprintf(stderr, "ldxb offset not supported!\n");
			exit(1);
		} else {
			bpf_set_curr_instr(BPF_LDX | BPF_MSH | BPF_B, 0, 0, $6); } }
	;

st
	: OP_ST 'M' '[' number ']' {
		bpf_set_curr_instr(BPF_ST, 0, 0, $4); }
	;

stx
	: OP_STX 'M' '[' number ']' {
		bpf_set_curr_instr(BPF_STX, 0, 0, $4); }
	;

jmp
	: OP_JMP label {
		bpf_set_jmp_label($2, JKL);
		bpf_set_curr_instr(BPF_JMP | BPF_JA, 0, 0, 0); }
	;

jeq
	: OP_JEQ '#' number ',' label ',' label {
		bpf_set_jmp_label($5, JTL);
		bpf_set_jmp_label($7, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_K, 0, 0, $3); }
	| OP_JEQ 'x' ',' label ',' label {
		bpf_set_jmp_label($4, JTL);
		bpf_set_jmp_label($6, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_X, 0, 0, 0); }
	| OP_JEQ '%' 'x' ',' label ',' label {
		bpf_set_jmp_label($5, JTL);
		bpf_set_jmp_label($7, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_X, 0, 0, 0); }
	| OP_JEQ '#' number ',' label {
		bpf_set_jmp_label($5, JTL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_K, 0, 0, $3); }
	| OP_JEQ 'x' ',' label {
		bpf_set_jmp_label($4, JTL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_X, 0, 0, 0); }
	| OP_JEQ '%' 'x' ',' label {
		bpf_set_jmp_label($5, JTL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_X, 0, 0, 0); }
	;

jneq
	: OP_JNEQ '#' number ',' label {
		bpf_set_jmp_label($5, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_K, 0, 0, $3); }
	| OP_JNEQ 'x' ',' label {
		bpf_set_jmp_label($4, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_X, 0, 0, 0); }
	| OP_JNEQ '%' 'x' ',' label {
		bpf_set_jmp_label($5, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JEQ | BPF_X, 0, 0, 0); }
	;

jlt
	: OP_JLT '#' number ',' label {
		bpf_set_jmp_label($5, JFL);
		bpf_set_curr_instr(BPF_JMP | BPF_JGE | BPF_K, 0, 0, $3); }
	| OP_JLT 'x' ',' label {

Annotation

• Immediate include surface: `stdio.h`, `string.h`, `stdint.h`, `stdlib.h`, `stdbool.h`, `unistd.h`, `errno.h`, `assert.h`.
• Detected declarations: `enum jmp_type`, `function bpf_assert_max`, `function bpf_set_curr_instr`, `function bpf_set_curr_label`, `function bpf_set_jmp_label`, `function bpf_find_insns_offset`, `function bpf_stage_1_insert_insns`, `function bpf_reduce_k_jumps`, `function bpf_encode_jt_jf_offset`, `function bpf_reduce_jt_jumps`.
• Atlas domain: Support Tooling And Documentation / tools.
• Implementation status: atlas-only.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.