lfs.c

Linux内核源代码 为压缩文件 是<<Linux内核>>一书中的源代码

/* $Id: lfs.c,v 1.1 1999/08/23 19:00:10 cort Exp $
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <asm/uaccess.h>

#include "soft-fp.h"
#include "double.h"
#include "single.h"

int
lfs(void *frD, void *ea)
{
	FP_DECL_D(R);
	FP_DECL_S(A);
	float f;

#ifdef DEBUG
	printk("%s: D %p, ea %p\n", __FUNCTION__, frD, ea);
#endif

	if (copy_from_user(&f, ea, sizeof(float)))
		return -EFAULT;

	__FP_UNPACK_S(A, &f);

#ifdef DEBUG
	printk("A: %ld %lu %ld (%ld) [%08lx]\n", A_s, A_f, A_e, A_c,
	       *(unsigned long *)&f);
#endif

	FP_CONV(D, S, 2, 1, R, A);

#ifdef DEBUG
	printk("R: %ld %lu %lu %ld (%ld)\n", R_s, R_f1, R_f0, R_e, R_c);
#endif

	return __FP_PACK_D(frD, R);
}