NetBSD/sys/kern/subr_copy.c

325 lines
8.9 KiB
C

/* $NetBSD: subr_copy.c,v 1.6 2015/04/21 13:17:25 riastradh Exp $ */
/*-
* Copyright (c) 1997, 1998, 1999, 2002, 2007, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* 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 form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
*
* 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 form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_subr.c 8.4 (Berkeley) 2/14/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: subr_copy.c,v 1.6 2015/04/21 13:17:25 riastradh Exp $");
#include <sys/param.h>
#include <sys/fcntl.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <uvm/uvm_extern.h>
void
uio_setup_sysspace(struct uio *uio)
{
uio->uio_vmspace = vmspace_kernel();
}
int
uiomove(void *buf, size_t n, struct uio *uio)
{
struct vmspace *vm = uio->uio_vmspace;
struct iovec *iov;
size_t cnt;
int error = 0;
char *cp = buf;
ASSERT_SLEEPABLE();
KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE);
while (n > 0 && uio->uio_resid) {
iov = uio->uio_iov;
cnt = iov->iov_len;
if (cnt == 0) {
KASSERT(uio->uio_iovcnt > 0);
uio->uio_iov++;
uio->uio_iovcnt--;
continue;
}
if (cnt > n)
cnt = n;
if (!VMSPACE_IS_KERNEL_P(vm)) {
if (curcpu()->ci_schedstate.spc_flags &
SPCF_SHOULDYIELD)
preempt();
}
if (uio->uio_rw == UIO_READ) {
error = copyout_vmspace(vm, cp, iov->iov_base,
cnt);
} else {
error = copyin_vmspace(vm, iov->iov_base, cp,
cnt);
}
if (error) {
break;
}
iov->iov_base = (char *)iov->iov_base + cnt;
iov->iov_len -= cnt;
uio->uio_resid -= cnt;
uio->uio_offset += cnt;
cp += cnt;
KDASSERT(cnt <= n);
n -= cnt;
}
return (error);
}
/*
* Wrapper for uiomove() that validates the arguments against a known-good
* kernel buffer.
*/
int
uiomove_frombuf(void *buf, size_t buflen, struct uio *uio)
{
size_t offset;
if (uio->uio_offset < 0 || /* uio->uio_resid < 0 || */
(offset = uio->uio_offset) != uio->uio_offset)
return (EINVAL);
if (offset >= buflen)
return (0);
return (uiomove((char *)buf + offset, buflen - offset, uio));
}
/*
* Give next character to user as result of read.
*/
int
ureadc(int c, struct uio *uio)
{
struct iovec *iov;
if (uio->uio_resid <= 0)
panic("ureadc: non-positive resid");
again:
if (uio->uio_iovcnt <= 0)
panic("ureadc: non-positive iovcnt");
iov = uio->uio_iov;
if (iov->iov_len <= 0) {
uio->uio_iovcnt--;
uio->uio_iov++;
goto again;
}
if (!VMSPACE_IS_KERNEL_P(uio->uio_vmspace)) {
if (subyte(iov->iov_base, c) < 0)
return (EFAULT);
} else {
*(char *)iov->iov_base = c;
}
iov->iov_base = (char *)iov->iov_base + 1;
iov->iov_len--;
uio->uio_resid--;
uio->uio_offset++;
return (0);
}
/*
* Like copyin(), but operates on an arbitrary vmspace.
*/
int
copyin_vmspace(struct vmspace *vm, const void *uaddr, void *kaddr, size_t len)
{
struct iovec iov;
struct uio uio;
int error;
if (len == 0)
return (0);
if (VMSPACE_IS_KERNEL_P(vm)) {
return kcopy(uaddr, kaddr, len);
}
if (__predict_true(vm == curproc->p_vmspace)) {
return copyin(uaddr, kaddr, len);
}
iov.iov_base = kaddr;
iov.iov_len = len;
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
uio.uio_offset = (off_t)(uintptr_t)uaddr;
uio.uio_resid = len;
uio.uio_rw = UIO_READ;
UIO_SETUP_SYSSPACE(&uio);
error = uvm_io(&vm->vm_map, &uio);
return (error);
}
/*
* Like copyout(), but operates on an arbitrary vmspace.
*/
int
copyout_vmspace(struct vmspace *vm, const void *kaddr, void *uaddr, size_t len)
{
struct iovec iov;
struct uio uio;
int error;
if (len == 0)
return (0);
if (VMSPACE_IS_KERNEL_P(vm)) {
return kcopy(kaddr, uaddr, len);
}
if (__predict_true(vm == curproc->p_vmspace)) {
return copyout(kaddr, uaddr, len);
}
iov.iov_base = __UNCONST(kaddr); /* XXXUNCONST cast away const */
iov.iov_len = len;
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
uio.uio_offset = (off_t)(uintptr_t)uaddr;
uio.uio_resid = len;
uio.uio_rw = UIO_WRITE;
UIO_SETUP_SYSSPACE(&uio);
error = uvm_io(&vm->vm_map, &uio);
return (error);
}
/*
* Like copyin(), but operates on an arbitrary process.
*/
int
copyin_proc(struct proc *p, const void *uaddr, void *kaddr, size_t len)
{
struct vmspace *vm;
int error;
error = proc_vmspace_getref(p, &vm);
if (error) {
return error;
}
error = copyin_vmspace(vm, uaddr, kaddr, len);
uvmspace_free(vm);
return error;
}
/*
* Like copyout(), but operates on an arbitrary process.
*/
int
copyout_proc(struct proc *p, const void *kaddr, void *uaddr, size_t len)
{
struct vmspace *vm;
int error;
error = proc_vmspace_getref(p, &vm);
if (error) {
return error;
}
error = copyout_vmspace(vm, kaddr, uaddr, len);
uvmspace_free(vm);
return error;
}
/*
* Like copyin(), except it operates on kernel addresses when the FKIOCTL
* flag is passed in `ioctlflags' from the ioctl call.
*/
int
ioctl_copyin(int ioctlflags, const void *src, void *dst, size_t len)
{
if (ioctlflags & FKIOCTL)
return kcopy(src, dst, len);
return copyin(src, dst, len);
}
/*
* Like copyout(), except it operates on kernel addresses when the FKIOCTL
* flag is passed in `ioctlflags' from the ioctl call.
*/
int
ioctl_copyout(int ioctlflags, const void *src, void *dst, size_t len)
{
if (ioctlflags & FKIOCTL)
return kcopy(src, dst, len);
return copyout(src, dst, len);
}