kernel/bpf/disasm.c

Source file repositories/reference/linux-study-clean/kernel/bpf/disasm.c

File Facts

System: Linux kernel
Corpus path: kernel/bpf/disasm.c
Extension: .c
Size: 12513 bytes
Lines: 394
Domain: Core OS
Bucket: Scheduler, Processes, Timers, Sync, And Syscalls
Inferred role: Core OS: implementation source
Status: source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

linux/bpf.h
disasm.h

Detected Declarations

function print_bpf_end_insn
function print_bpf_bswap_insn
function is_sdiv_smod
function is_movsx
function is_addr_space_cast
function is_mov_percpu_addr
function print_bpf_insn
function BPF_SIZE

Annotated Snippet

if (BPF_OP(insn->code) == BPF_END) {
			if (class == BPF_ALU64)
				print_bpf_bswap_insn(verbose, cbs->private_data, insn);
			else
				print_bpf_end_insn(verbose, cbs->private_data, insn);
		} else if (BPF_OP(insn->code) == BPF_NEG) {
			verbose(cbs->private_data, "(%02x) %c%d = -%c%d\n",
				insn->code, class == BPF_ALU ? 'w' : 'r',
				insn->dst_reg, class == BPF_ALU ? 'w' : 'r',
				insn->dst_reg);
		} else if (is_addr_space_cast(insn)) {
			verbose(cbs->private_data, "(%02x) r%d = addr_space_cast(r%d, %u, %u)\n",
				insn->code, insn->dst_reg,
				insn->src_reg, ((u32)insn->imm) >> 16, (u16)insn->imm);
		} else if (is_mov_percpu_addr(insn)) {
			verbose(cbs->private_data, "(%02x) r%d = &(void __percpu *)(r%d)\n",
				insn->code, insn->dst_reg, insn->src_reg);
		} else if (BPF_SRC(insn->code) == BPF_X) {
			verbose(cbs->private_data, "(%02x) %c%d %s %s%c%d\n",
				insn->code, class == BPF_ALU ? 'w' : 'r',
				insn->dst_reg,
				is_sdiv_smod(insn) ? bpf_alu_sign_string[BPF_OP(insn->code) >> 4]
						   : bpf_alu_string[BPF_OP(insn->code) >> 4],
				is_movsx(insn) ? bpf_movsx_string[(insn->off >> 3) - 1] : "",
				class == BPF_ALU ? 'w' : 'r',
				insn->src_reg);
		} else {
			verbose(cbs->private_data, "(%02x) %c%d %s %d\n",
				insn->code, class == BPF_ALU ? 'w' : 'r',
				insn->dst_reg,
				is_sdiv_smod(insn) ? bpf_alu_sign_string[BPF_OP(insn->code) >> 4]
						   : bpf_alu_string[BPF_OP(insn->code) >> 4],
				insn->imm);
		}
	} else if (class == BPF_STX) {
		if (BPF_MODE(insn->code) == BPF_MEM)
			verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = r%d\n",
				insn->code,
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->dst_reg,
				insn->off, insn->src_reg);
		else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
			 (insn->imm == BPF_ADD || insn->imm == BPF_AND ||
			  insn->imm == BPF_OR || insn->imm == BPF_XOR)) {
			verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n",
				insn->code,
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->dst_reg, insn->off,
				bpf_alu_string[BPF_OP(insn->imm) >> 4],
				insn->src_reg);
		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
			   (insn->imm == (BPF_ADD | BPF_FETCH) ||
			    insn->imm == (BPF_AND | BPF_FETCH) ||
			    insn->imm == (BPF_OR | BPF_FETCH) ||
			    insn->imm == (BPF_XOR | BPF_FETCH))) {
			verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n",
				insn->code, insn->src_reg,
				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
				bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4],
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->dst_reg, insn->off, insn->src_reg);
		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
			   insn->imm == BPF_CMPXCHG) {
			verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n",
				insn->code,
				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->dst_reg, insn->off,
				insn->src_reg);
		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
			   insn->imm == BPF_XCHG) {
			verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n",
				insn->code, insn->src_reg,
				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->dst_reg, insn->off, insn->src_reg);
		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
			   insn->imm == BPF_LOAD_ACQ) {
			verbose(cbs->private_data, "(%02x) r%d = load_acquire((%s *)(r%d %+d))\n",
				insn->code, insn->dst_reg,
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->src_reg, insn->off);
		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
			   insn->imm == BPF_STORE_REL) {
			verbose(cbs->private_data, "(%02x) store_release((%s *)(r%d %+d), r%d)\n",
				insn->code,
				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
				insn->dst_reg, insn->off, insn->src_reg);
		} else {
			verbose(cbs->private_data, "BUG_%02x\n", insn->code);

Annotation

Immediate include surface: `linux/bpf.h`, `disasm.h`.
Detected declarations: `function print_bpf_end_insn`, `function print_bpf_bswap_insn`, `function is_sdiv_smod`, `function is_movsx`, `function is_addr_space_cast`, `function is_mov_percpu_addr`, `function print_bpf_insn`, `function BPF_SIZE`.
Atlas domain: Core OS / Scheduler, Processes, Timers, Sync, And Syscalls.
Implementation status: source implementation candidate.
Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

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.