1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
27 /* All Rights Reserved */
28
29 /*
30 * University Copyright- Copyright (c) 1982, 1986, 1988
31 * The Regents of the University of California
32 * All Rights Reserved
33 *
34 * University Acknowledgment- Portions of this document are derived from
35 * software developed by the University of California, Berkeley, and its
36 * contributors.
37 */
38
39 /*
40 */
41
42 #include <sys/types.h>
43 #include <sys/uio.h>
44 #include <sys/vnode.h>
45
46 /*
47 * same as uiomove() but doesn't modify uio structure.
48 * return in cbytes how many bytes were copied.
49 */
50 int
uiocopy(void * p,size_t n,enum uio_rw rw,struct uio * uio,size_t * cbytes)51 uiocopy(void *p, size_t n, enum uio_rw rw, struct uio *uio, size_t *cbytes)
52 {
53 struct iovec small_iovec[1];
54 struct uio small_uio_clone;
55 struct uio *uio_clone;
56 int error;
57
58 ASSERT3U(uio->uio_rw, ==, rw);
59 if (uio->uio_iovcnt == 1) {
60 small_uio_clone = *uio;
61 small_iovec[0] = *uio->uio_iov;
62 small_uio_clone.uio_iov = small_iovec;
63 uio_clone = &small_uio_clone;
64 } else {
65 uio_clone = cloneuio(uio);
66 }
67
68 error = vn_io_fault_uiomove(p, n, uio_clone);
69 *cbytes = uio->uio_resid - uio_clone->uio_resid;
70 if (uio_clone != &small_uio_clone)
71 freeuio(uio_clone);
72 return (error);
73 }
74
75 /*
76 * Drop the next n chars out of *uiop.
77 */
78 void
uioskip(uio_t * uio,size_t n)79 uioskip(uio_t *uio, size_t n)
80 {
81 enum uio_seg segflg;
82
83 /* For the full compatibility with illumos. */
84 if (n > uio->uio_resid)
85 return;
86
87 segflg = uio->uio_segflg;
88 uio->uio_segflg = UIO_NOCOPY;
89 uiomove(NULL, n, uio->uio_rw, uio);
90 uio->uio_segflg = segflg;
91 }
92