arch/powerpc/math-emu/lfd.c

File Facts

System

Linux kernel

Corpus path

arch/powerpc/math-emu/lfd.c

Extension

.c

Size

384 bytes

Lines

21

Domain

Architecture Layer

Bucket

arch/powerpc

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.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.

Dependency Surface

• linux/types.h
• linux/errno.h
• linux/uaccess.h
• asm/sfp-machine.h
• math-emu/double.h

Detected Declarations

• function lfd

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/uaccess.h>

#include <asm/sfp-machine.h>
#include <math-emu/double.h>

int
lfd(void *frD, void *ea)
{
	if (copy_from_user(frD, ea, sizeof(double)))
		return -EFAULT;
#ifdef DEBUG
	printk("%s: D %p, ea %p: ", __func__, frD, ea);
	dump_double(frD);
	printk("\n");
#endif
	return 0;
}

Annotation

• Immediate include surface: `linux/types.h`, `linux/errno.h`, `linux/uaccess.h`, `asm/sfp-machine.h`, `math-emu/double.h`.
• Detected declarations: `function lfd`.
• Atlas domain: Architecture Layer / arch/powerpc.
• Implementation status: source implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.

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.