arch/x86/um/asm/checksum_32.h

File Facts

System

Linux kernel

Corpus path

arch/x86/um/asm/checksum_32.h

Extension

.h

Size

804 bytes

Lines

39

Domain

Architecture Layer

Bucket

arch/x86

Inferred role

Architecture Layer: implementation source

Status

source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• No C-style include directives detected by the generator.

Detected Declarations

• function ip_compute_csum
• function csum_ipv6_magic

Annotated Snippet

#ifndef __UM_SYSDEP_CHECKSUM_H
#define __UM_SYSDEP_CHECKSUM_H

static inline __sum16 ip_compute_csum(const void *buff, int len)
{
    return csum_fold (csum_partial(buff, len, 0));
}

#define _HAVE_ARCH_IPV6_CSUM
static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
					  const struct in6_addr *daddr,
					  __u32 len, __u8 proto,
					  __wsum sum)
{
	__asm__(
		"addl 0(%1), %0		;\n"
		"adcl 4(%1), %0		;\n"
		"adcl 8(%1), %0		;\n"
		"adcl 12(%1), %0	;\n"
		"adcl 0(%2), %0		;\n"
		"adcl 4(%2), %0		;\n"
		"adcl 8(%2), %0		;\n"
		"adcl 12(%2), %0	;\n"
		"adcl %3, %0		;\n"
		"adcl %4, %0		;\n"
		"adcl $0, %0		;\n"
		: "=&r" (sum)
		: "r" (saddr), "r" (daddr),
		  "r"(htonl(len)), "r"(htonl(proto)), "0"(sum));

	return csum_fold(sum);
}

#endif

Annotation

• Detected declarations: `function ip_compute_csum`, `function csum_ipv6_magic`.
• Atlas domain: Architecture Layer / arch/x86.
• 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.