Content-type: text/html Man page of uiomove

uiomove

Section: Kernel Functions for Drivers (9F)
Updated: 16 Jan 2006
Index Return to Main Contents
 

NAME

uiomove - copy kernel data using uio structure  

SYNOPSIS

#include <sys/types.h>
#include <sys/uio.h>

int uiomove(caddr_t address, size_t nbytes, enum uio_rw rwflag, uio_t *uio_p);  

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).  

PARAMETERS

address Source/destination kernel address of the copy.

nbytes Number of bytes to copy.

rwflag Flag indicating read or write operation. Possible values are UIO_READ and UIO_WRITE.

uio_p Pointer to the uio structure for the copy.

 

DESCRIPTION

The uiomove() function copies nbytes of data to or from the space defined by the uio structure (described in uio(9S)) and the driver.

The uio_segflg member of the uio(9S) structure determines the type of space to or from which the transfer is being made. If it is set to UIO_SYSSPACE, the data transfer is between addresses in the kernel. If it is set to UIO_USERSPACE, the transfer is between a user program and kernel space.

rwflag indicates the direction of the transfer. If UIO_READ is set, the data will be transferred from address to the buffer(s) described by uio_p. If UIO_WRITE is set, the data will be transferred from the buffer(s) described by uio_p to address.

In addition to moving the data, uiomove() adds the number of bytes moved to the iov_base member of the iovec(9S) structure, decreases the iov_len member, increases the uio_offset member of the uio(9S) structure, and decreases the uio_resid member.

This function automatically handles page faults. nbytes does not have to be word-aligned.  

RETURN VALUES

The uiomove() function returns 0 upon success or EFAULT on failure.  

CONTEXT

User context only, if uio_segflg is set to UIO_USERSPACE. User, interrupt, or kernel context, if uio_segflg is set to UIO_SYSSPACE.  

SEE ALSO

ureadc(9F), uwritec(9F), iovec(9S), uio(9S)

Writing Device Drivers  

WARNINGS

If uio_segflg is set to UIO_SYSSPACE and address is selected from user space, the system may panic.


 

Index

NAME
SYNOPSIS
INTERFACE LEVEL
PARAMETERS
DESCRIPTION
RETURN VALUES
CONTEXT
SEE ALSO
WARNINGS

This document was created by man2html, using the manual pages.
Time: 02:39:42 GMT, October 02, 2010