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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California
* All Rights Reserved
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
/*
* The uio support from OpenSolaris has been added as a short term
* work around. The hope is to adopt native Linux type and drop the
* use of uio's entirely. Under Linux they only add overhead and
* when possible we want to use native APIs for the ZPL layer.
*/
#ifdef _KERNEL
#include <sys/types.h>
#include <sys/uio_impl.h>
/*
* Move "n" bytes at byte address "p"; "rw" indicates the direction
* of the move, and the I/O parameters are provided in "uio", which is
* update to reflect the data which was moved. Returns 0 on success or
* a non-zero errno on failure.
*/
int
uiomove(void *p, size_t n, enum uio_rw rw, struct uio *uio)
{
struct iovec *iov;
ulong_t cnt;
while (n && uio->uio_resid) {
iov = uio->uio_iov;
cnt = MIN(iov->iov_len, n);
if (cnt == 0l) {
uio->uio_iov++;
uio->uio_iovcnt--;
continue;
}
switch (uio->uio_segflg) {
case UIO_USERSPACE:
case UIO_USERISPACE:
/*
* p = kernel data pointer
* iov->iov_base = user data pointer
*/
if (rw == UIO_READ) {
if (copy_to_user(iov->iov_base, p, cnt))
return (EFAULT);
} else {
if (copy_from_user(p, iov->iov_base, cnt))
return (EFAULT);
}
break;
case UIO_SYSSPACE:
if (rw == UIO_READ)
bcopy(p, iov->iov_base, cnt);
else
bcopy(iov->iov_base, p, cnt);
break;
}
iov->iov_base += cnt;
iov->iov_len -= cnt;
uio->uio_resid -= cnt;
uio->uio_loffset += cnt;
p = (caddr_t)p + cnt;
n -= cnt;
}
return (0);
}
EXPORT_SYMBOL(uiomove);
#define fuword8(uptr, vptr) get_user((*vptr), (uptr))
/*
* Fault in the pages of the first n bytes specified by the uio structure.
* 1 byte in each page is touched and the uio struct is unmodified. Any
* error will terminate the process as this is only a best attempt to get
* the pages resident.
*/
void
uio_prefaultpages(ssize_t n, struct uio *uio)
{
struct iovec *iov;
ulong_t cnt, incr;
caddr_t p;
uint8_t tmp;
int iovcnt;
iov = uio->uio_iov;
iovcnt = uio->uio_iovcnt;
while ((n > 0) && (iovcnt > 0)) {
cnt = MIN(iov->iov_len, n);
if (cnt == 0) {
/* empty iov entry */
iov++;
iovcnt--;
continue;
}
n -= cnt;
/*
* touch each page in this segment.
*/
p = iov->iov_base;
while (cnt) {
switch (uio->uio_segflg) {
case UIO_USERSPACE:
case UIO_USERISPACE:
if (fuword8((uint8_t *) p, &tmp))
return;
break;
case UIO_SYSSPACE:
bcopy(p, &tmp, 1);
break;
}
incr = MIN(cnt, PAGESIZE);
p += incr;
cnt -= incr;
}
/*
* touch the last byte in case it straddles a page.
*/
p--;
switch (uio->uio_segflg) {
case UIO_USERSPACE:
case UIO_USERISPACE:
if (fuword8((uint8_t *) p, &tmp))
return;
break;
case UIO_SYSSPACE:
bcopy(p, &tmp, 1);
break;
}
iov++;
iovcnt--;
}
}
EXPORT_SYMBOL(uio_prefaultpages);
/*
* same as uiomove() but doesn't modify uio structure.
* return in cbytes how many bytes were copied.
*/
int
uiocopy(void *p, size_t n, enum uio_rw rw, struct uio *uio, size_t *cbytes)
{
struct iovec *iov;
ulong_t cnt;
int iovcnt;
iovcnt = uio->uio_iovcnt;
*cbytes = 0;
for (iov = uio->uio_iov; n && iovcnt; iov++, iovcnt--) {
cnt = MIN(iov->iov_len, n);
if (cnt == 0)
continue;
switch (uio->uio_segflg) {
case UIO_USERSPACE:
case UIO_USERISPACE:
/*
* p = kernel data pointer
* iov->iov_base = user data pointer
*/
if (rw == UIO_READ) {
/* UIO_READ = copy data from kernel to user */
if (copy_to_user(iov->iov_base, p, cnt))
return (EFAULT);
} else {
/* UIO_WRITE = copy data from user to kernel */
if (copy_from_user(p, iov->iov_base, cnt))
return (EFAULT);
}
break;
case UIO_SYSSPACE:
if (rw == UIO_READ)
bcopy(p, iov->iov_base, cnt);
else
bcopy(iov->iov_base, p, cnt);
break;
}
p = (caddr_t)p + cnt;
n -= cnt;
*cbytes += cnt;
}
return (0);
}
EXPORT_SYMBOL(uiocopy);
/*
* Drop the next n chars out of *uiop.
*/
void
uioskip(uio_t *uiop, size_t n)
{
if (n > uiop->uio_resid)
return;
while (n != 0) {
iovec_t *iovp = uiop->uio_iov;
size_t niovb = MIN(iovp->iov_len, n);
if (niovb == 0) {
uiop->uio_iov++;
uiop->uio_iovcnt--;
continue;
}
iovp->iov_base += niovb;
uiop->uio_loffset += niovb;
iovp->iov_len -= niovb;
uiop->uio_resid -= niovb;
n -= niovb;
}
}
EXPORT_SYMBOL(uioskip);
#endif /* _KERNEL */
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