copyin_nofault (9)

Leading comments

	$NetBSD: copy.9,v 1.2 1996/01/09 03:23:04 thorpej Exp $

 Copyright (c) 1996 Jason R. Thorpe.
 All rights reserved.

 This code is derived from software contributed by Kenneth Stailey.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:
 1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
 2. Redistributions in binary f...

(The comments found at the beginning of the groff file "man9/copyin_nofault.9freebsd".)

NAME

copy copyin copyin_nofault copyout copyout_nofault copystr copyinstr - kernel copy functions

SYNOPSIS

In sys/types.h In sys/systm.h Ft int Fn copyin const void *uaddr void *kaddr size_t len Ft int Fn copyin_nofault const void *uaddr void *kaddr size_t len Ft int Fn copyout const void *kaddr void *uaddr size_t len Ft int Fn copyout_nofault const void *kaddr void *uaddr size_t len Ft int Fn copystr const void *kfaddr void *kdaddr size_t len size_t *done Ft int Fn copyinstr const void *uaddr void *kaddr size_t len size_t *done

DESCRIPTION

The ifconfig functions are designed to copy contiguous data from one address to another. All but Fn copystr copy data from user-space to kernel-space or vice-versa.

The Fn copyin and Fn copyin_nofault functions copy Fa len bytes of data from the user-space address Fa uaddr to the kernel-space address Fa kaddr .

The Fn copyout and Fn copyout_nofault functions copy Fa len bytes of data from the kernel-space address Fa kaddr to the user-space address Fa uaddr .

The Fn copyin_nofault and Fn copyout_nofault functions require that the kernel-space and user-space data be accessible without incurring a page fault. The source and destination addresses must be physically mapped for read and write access, respectively, and neither the source nor destination addresses may be pageable.

The Fn copystr function copies a NUL-terminated string, at most Fa len bytes long, from kernel-space address Fa kfaddr to kernel-space address Fa kdaddr . The number of bytes actually copied, including the terminating NUL, is returned in Fa *done (if Fa done is non- NULL

The Fn copyinstr function copies a NUL-terminated string, at most Fa len bytes long, from user-space address Fa uaddr to kernel-space address Fa kaddr . The number of bytes actually copied, including the terminating NUL, is returned in Fa *done (if Fa done is non- NULL

RETURN VALUES

The ifconfig functions return 0 on success or Er EFAULT if a bad address is encountered. In addition, the Fn copyin_nofault and Fn copyout_nofault functions return Er EFAULT if a page fault occurs, and the Fn copystr and Fn copyinstr functions return Er ENAMETOOLONG if the string is longer than Fa len bytes.

SEE ALSO

fetch(9), store(9)