lib/raid/xor/alpha/xor.c

File Facts

System

Linux kernel

Corpus path

lib/raid/xor/alpha/xor.c

Extension

.c

Size

21973 bytes

Lines

849

Domain

Kernel Services

Bucket

lib

Inferred role

Kernel Services: implementation source

Status

source implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

• Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• xor_impl.h
• xor_arch.h

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Optimized XOR parity functions for alpha EV5 and EV6
 */
#include "xor_impl.h"
#include "xor_arch.h"

extern void
xor_alpha_2(unsigned long bytes, unsigned long * __restrict p1,
	    const unsigned long * __restrict p2);
extern void
xor_alpha_3(unsigned long bytes, unsigned long * __restrict p1,
	    const unsigned long * __restrict p2,
	    const unsigned long * __restrict p3);
extern void
xor_alpha_4(unsigned long bytes, unsigned long * __restrict p1,
	    const unsigned long * __restrict p2,
	    const unsigned long * __restrict p3,
	    const unsigned long * __restrict p4);
extern void
xor_alpha_5(unsigned long bytes, unsigned long * __restrict p1,
	    const unsigned long * __restrict p2,
	    const unsigned long * __restrict p3,
	    const unsigned long * __restrict p4,
	    const unsigned long * __restrict p5);

extern void
xor_alpha_prefetch_2(unsigned long bytes, unsigned long * __restrict p1,
		     const unsigned long * __restrict p2);
extern void
xor_alpha_prefetch_3(unsigned long bytes, unsigned long * __restrict p1,
		     const unsigned long * __restrict p2,
		     const unsigned long * __restrict p3);
extern void
xor_alpha_prefetch_4(unsigned long bytes, unsigned long * __restrict p1,
		     const unsigned long * __restrict p2,
		     const unsigned long * __restrict p3,
		     const unsigned long * __restrict p4);
extern void
xor_alpha_prefetch_5(unsigned long bytes, unsigned long * __restrict p1,
		     const unsigned long * __restrict p2,
		     const unsigned long * __restrict p3,
		     const unsigned long * __restrict p4,
		     const unsigned long * __restrict p5);

asm("								\n\
	.text							\n\
	.align 3						\n\
	.ent xor_alpha_2					\n\
xor_alpha_2:							\n\
	.prologue 0						\n\
	srl $16, 6, $16						\n\
	.align 4						\n\
2:								\n\
	ldq $0,0($17)						\n\
	ldq $1,0($18)						\n\
	ldq $2,8($17)						\n\
	ldq $3,8($18)						\n\
								\n\
	ldq $4,16($17)						\n\
	ldq $5,16($18)						\n\
	ldq $6,24($17)						\n\
	ldq $7,24($18)						\n\
								\n\
	ldq $19,32($17)						\n\
	ldq $20,32($18)						\n\
	ldq $21,40($17)						\n\
	ldq $22,40($18)						\n\
								\n\
	ldq $23,48($17)						\n\
	ldq $24,48($18)						\n\
	ldq $25,56($17)						\n\
	xor $0,$1,$0		# 7 cycles from $1 load		\n\
								\n\
	ldq $27,56($18)						\n\
	xor $2,$3,$2						\n\
	stq $0,0($17)						\n\
	xor $4,$5,$4						\n\
								\n\
	stq $2,8($17)						\n\
	xor $6,$7,$6						\n\
	stq $4,16($17)						\n\
	xor $19,$20,$19						\n\
								\n\
	stq $6,24($17)						\n\
	xor $21,$22,$21						\n\
	stq $19,32($17)						\n\
	xor $23,$24,$23						\n\
								\n\
	stq $21,40($17)						\n\

Annotation

• Immediate include surface: `xor_impl.h`, `xor_arch.h`.
• Atlas domain: Kernel Services / lib.
• Implementation status: source implementation candidate.

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.