xref: /onnv-gate/usr/src/uts/common/os/move.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
29*0Sstevel@tonic-gate 
30*0Sstevel@tonic-gate /*
31*0Sstevel@tonic-gate  * University Copyright- Copyright (c) 1982, 1986, 1988
32*0Sstevel@tonic-gate  * The Regents of the University of California
33*0Sstevel@tonic-gate  * All Rights Reserved
34*0Sstevel@tonic-gate  *
35*0Sstevel@tonic-gate  * University Acknowledgment- Portions of this document are derived from
36*0Sstevel@tonic-gate  * software developed by the University of California, Berkeley, and its
37*0Sstevel@tonic-gate  * contributors.
38*0Sstevel@tonic-gate  */
39*0Sstevel@tonic-gate 
40*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
41*0Sstevel@tonic-gate 
42*0Sstevel@tonic-gate #include <sys/types.h>
43*0Sstevel@tonic-gate #include <sys/sysmacros.h>
44*0Sstevel@tonic-gate #include <sys/param.h>
45*0Sstevel@tonic-gate #include <sys/systm.h>
46*0Sstevel@tonic-gate #include <sys/uio.h>
47*0Sstevel@tonic-gate #include <sys/errno.h>
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate /*
50*0Sstevel@tonic-gate  * Move "n" bytes at byte address "p"; "rw" indicates the direction
51*0Sstevel@tonic-gate  * of the move, and the I/O parameters are provided in "uio", which is
52*0Sstevel@tonic-gate  * update to reflect the data which was moved.  Returns 0 on success or
53*0Sstevel@tonic-gate  * a non-zero errno on failure.
54*0Sstevel@tonic-gate  */
55*0Sstevel@tonic-gate int
56*0Sstevel@tonic-gate uiomove(void *p, size_t n, enum uio_rw rw, struct uio *uio)
57*0Sstevel@tonic-gate {
58*0Sstevel@tonic-gate 	struct iovec *iov;
59*0Sstevel@tonic-gate 	ulong_t cnt;
60*0Sstevel@tonic-gate 	int error;
61*0Sstevel@tonic-gate 
62*0Sstevel@tonic-gate 	while (n && uio->uio_resid) {
63*0Sstevel@tonic-gate 		iov = uio->uio_iov;
64*0Sstevel@tonic-gate 		cnt = MIN(iov->iov_len, n);
65*0Sstevel@tonic-gate 		if (cnt == 0l) {
66*0Sstevel@tonic-gate 			uio->uio_iov++;
67*0Sstevel@tonic-gate 			uio->uio_iovcnt--;
68*0Sstevel@tonic-gate 			continue;
69*0Sstevel@tonic-gate 		}
70*0Sstevel@tonic-gate 		switch (uio->uio_segflg) {
71*0Sstevel@tonic-gate 
72*0Sstevel@tonic-gate 		case UIO_USERSPACE:
73*0Sstevel@tonic-gate 		case UIO_USERISPACE:
74*0Sstevel@tonic-gate 			if (rw == UIO_READ) {
75*0Sstevel@tonic-gate 				error = xcopyout_nta(p, iov->iov_base, cnt,
76*0Sstevel@tonic-gate 				    (uio->uio_extflg & UIO_COPY_CACHED));
77*0Sstevel@tonic-gate 			} else {
78*0Sstevel@tonic-gate 				error = xcopyin_nta(iov->iov_base, p, cnt,
79*0Sstevel@tonic-gate 				    (uio->uio_extflg & UIO_COPY_CACHED));
80*0Sstevel@tonic-gate 			}
81*0Sstevel@tonic-gate 
82*0Sstevel@tonic-gate 			if (error)
83*0Sstevel@tonic-gate 				return (error);
84*0Sstevel@tonic-gate 			break;
85*0Sstevel@tonic-gate 
86*0Sstevel@tonic-gate 		case UIO_SYSSPACE:
87*0Sstevel@tonic-gate 			if (rw == UIO_READ)
88*0Sstevel@tonic-gate 				error = kcopy_nta(p, iov->iov_base, cnt,
89*0Sstevel@tonic-gate 				    (uio->uio_extflg & UIO_COPY_CACHED));
90*0Sstevel@tonic-gate 			else
91*0Sstevel@tonic-gate 				error = kcopy_nta(iov->iov_base, p, cnt,
92*0Sstevel@tonic-gate 				    (uio->uio_extflg & UIO_COPY_CACHED));
93*0Sstevel@tonic-gate 			if (error)
94*0Sstevel@tonic-gate 				return (error);
95*0Sstevel@tonic-gate 			break;
96*0Sstevel@tonic-gate 		}
97*0Sstevel@tonic-gate 		iov->iov_base += cnt;
98*0Sstevel@tonic-gate 		iov->iov_len -= cnt;
99*0Sstevel@tonic-gate 		uio->uio_resid -= cnt;
100*0Sstevel@tonic-gate 		uio->uio_loffset += cnt;
101*0Sstevel@tonic-gate 		p = (caddr_t)p + cnt;
102*0Sstevel@tonic-gate 		n -= cnt;
103*0Sstevel@tonic-gate 	}
104*0Sstevel@tonic-gate 	return (0);
105*0Sstevel@tonic-gate }
106*0Sstevel@tonic-gate 
107*0Sstevel@tonic-gate /*
108*0Sstevel@tonic-gate  * transfer a character value into the address space
109*0Sstevel@tonic-gate  * delineated by a uio and update fields within the
110*0Sstevel@tonic-gate  * uio for next character. Return 0 for success, EFAULT
111*0Sstevel@tonic-gate  * for error.
112*0Sstevel@tonic-gate  */
113*0Sstevel@tonic-gate int
114*0Sstevel@tonic-gate ureadc(int val, struct uio *uiop)
115*0Sstevel@tonic-gate {
116*0Sstevel@tonic-gate 	struct iovec *iovp;
117*0Sstevel@tonic-gate 	unsigned char c;
118*0Sstevel@tonic-gate 
119*0Sstevel@tonic-gate 	/*
120*0Sstevel@tonic-gate 	 * first determine if uio is valid.  uiop should be
121*0Sstevel@tonic-gate 	 * non-NULL and the resid count > 0.
122*0Sstevel@tonic-gate 	 */
123*0Sstevel@tonic-gate 	if (!(uiop && uiop->uio_resid > 0))
124*0Sstevel@tonic-gate 		return (EFAULT);
125*0Sstevel@tonic-gate 
126*0Sstevel@tonic-gate 	/*
127*0Sstevel@tonic-gate 	 * scan through iovecs until one is found that is non-empty.
128*0Sstevel@tonic-gate 	 * Return EFAULT if none found.
129*0Sstevel@tonic-gate 	 */
130*0Sstevel@tonic-gate 	while (uiop->uio_iovcnt > 0) {
131*0Sstevel@tonic-gate 		iovp = uiop->uio_iov;
132*0Sstevel@tonic-gate 		if (iovp->iov_len <= 0) {
133*0Sstevel@tonic-gate 			uiop->uio_iovcnt--;
134*0Sstevel@tonic-gate 			uiop->uio_iov++;
135*0Sstevel@tonic-gate 		} else
136*0Sstevel@tonic-gate 			break;
137*0Sstevel@tonic-gate 	}
138*0Sstevel@tonic-gate 
139*0Sstevel@tonic-gate 	if (uiop->uio_iovcnt <= 0)
140*0Sstevel@tonic-gate 		return (EFAULT);
141*0Sstevel@tonic-gate 
142*0Sstevel@tonic-gate 	/*
143*0Sstevel@tonic-gate 	 * Transfer character to uio space.
144*0Sstevel@tonic-gate 	 */
145*0Sstevel@tonic-gate 
146*0Sstevel@tonic-gate 	c = (unsigned char) (val & 0xFF);
147*0Sstevel@tonic-gate 
148*0Sstevel@tonic-gate 	switch (uiop->uio_segflg) {
149*0Sstevel@tonic-gate 
150*0Sstevel@tonic-gate 	case UIO_USERISPACE:
151*0Sstevel@tonic-gate 	case UIO_USERSPACE:
152*0Sstevel@tonic-gate 		if (copyout(&c, iovp->iov_base, sizeof (unsigned char)))
153*0Sstevel@tonic-gate 			return (EFAULT);
154*0Sstevel@tonic-gate 		break;
155*0Sstevel@tonic-gate 
156*0Sstevel@tonic-gate 	case UIO_SYSSPACE: /* can do direct copy since kernel-kernel */
157*0Sstevel@tonic-gate 		*iovp->iov_base = c;
158*0Sstevel@tonic-gate 		break;
159*0Sstevel@tonic-gate 
160*0Sstevel@tonic-gate 	default:
161*0Sstevel@tonic-gate 		return (EFAULT); /* invalid segflg value */
162*0Sstevel@tonic-gate 	}
163*0Sstevel@tonic-gate 
164*0Sstevel@tonic-gate 	/*
165*0Sstevel@tonic-gate 	 * bump up/down iovec and uio members to reflect transfer.
166*0Sstevel@tonic-gate 	 */
167*0Sstevel@tonic-gate 	iovp->iov_base++;
168*0Sstevel@tonic-gate 	iovp->iov_len--;
169*0Sstevel@tonic-gate 	uiop->uio_resid--;
170*0Sstevel@tonic-gate 	uiop->uio_loffset++;
171*0Sstevel@tonic-gate 	return (0); /* success */
172*0Sstevel@tonic-gate }
173*0Sstevel@tonic-gate 
174*0Sstevel@tonic-gate /*
175*0Sstevel@tonic-gate  * return a character value from the address space
176*0Sstevel@tonic-gate  * delineated by a uio and update fields within the
177*0Sstevel@tonic-gate  * uio for next character. Return the character for success,
178*0Sstevel@tonic-gate  * -1 for error.
179*0Sstevel@tonic-gate  */
180*0Sstevel@tonic-gate int
181*0Sstevel@tonic-gate uwritec(struct uio *uiop)
182*0Sstevel@tonic-gate {
183*0Sstevel@tonic-gate 	struct iovec *iovp;
184*0Sstevel@tonic-gate 	unsigned char c;
185*0Sstevel@tonic-gate 
186*0Sstevel@tonic-gate 	/*
187*0Sstevel@tonic-gate 	 * verify we were passed a valid uio structure.
188*0Sstevel@tonic-gate 	 * (1) non-NULL uiop, (2) positive resid count
189*0Sstevel@tonic-gate 	 * (3) there is an iovec with positive length
190*0Sstevel@tonic-gate 	 */
191*0Sstevel@tonic-gate 
192*0Sstevel@tonic-gate 	if (!(uiop && uiop->uio_resid > 0))
193*0Sstevel@tonic-gate 		return (-1);
194*0Sstevel@tonic-gate 
195*0Sstevel@tonic-gate 	while (uiop->uio_iovcnt > 0) {
196*0Sstevel@tonic-gate 		iovp = uiop->uio_iov;
197*0Sstevel@tonic-gate 		if (iovp->iov_len <= 0) {
198*0Sstevel@tonic-gate 			uiop->uio_iovcnt--;
199*0Sstevel@tonic-gate 			uiop->uio_iov++;
200*0Sstevel@tonic-gate 		} else
201*0Sstevel@tonic-gate 			break;
202*0Sstevel@tonic-gate 	}
203*0Sstevel@tonic-gate 
204*0Sstevel@tonic-gate 	if (uiop->uio_iovcnt <= 0)
205*0Sstevel@tonic-gate 		return (-1);
206*0Sstevel@tonic-gate 
207*0Sstevel@tonic-gate 	/*
208*0Sstevel@tonic-gate 	 * Get the character from the uio address space.
209*0Sstevel@tonic-gate 	 */
210*0Sstevel@tonic-gate 	switch (uiop->uio_segflg) {
211*0Sstevel@tonic-gate 
212*0Sstevel@tonic-gate 	case UIO_USERISPACE:
213*0Sstevel@tonic-gate 	case UIO_USERSPACE:
214*0Sstevel@tonic-gate 		if (copyin(iovp->iov_base, &c, sizeof (unsigned char)))
215*0Sstevel@tonic-gate 			return (-1);
216*0Sstevel@tonic-gate 		break;
217*0Sstevel@tonic-gate 
218*0Sstevel@tonic-gate 	case UIO_SYSSPACE:
219*0Sstevel@tonic-gate 		c = *iovp->iov_base;
220*0Sstevel@tonic-gate 		break;
221*0Sstevel@tonic-gate 
222*0Sstevel@tonic-gate 	default:
223*0Sstevel@tonic-gate 		return (-1); /* invalid segflg */
224*0Sstevel@tonic-gate 	}
225*0Sstevel@tonic-gate 
226*0Sstevel@tonic-gate 	/*
227*0Sstevel@tonic-gate 	 * Adjust fields of iovec and uio appropriately.
228*0Sstevel@tonic-gate 	 */
229*0Sstevel@tonic-gate 	iovp->iov_base++;
230*0Sstevel@tonic-gate 	iovp->iov_len--;
231*0Sstevel@tonic-gate 	uiop->uio_resid--;
232*0Sstevel@tonic-gate 	uiop->uio_loffset++;
233*0Sstevel@tonic-gate 	return ((int)c & 0xFF); /* success */
234*0Sstevel@tonic-gate }
235*0Sstevel@tonic-gate 
236*0Sstevel@tonic-gate /*
237*0Sstevel@tonic-gate  * Drop the next n chars out of *uiop.
238*0Sstevel@tonic-gate  */
239*0Sstevel@tonic-gate void
240*0Sstevel@tonic-gate uioskip(uio_t *uiop, size_t n)
241*0Sstevel@tonic-gate {
242*0Sstevel@tonic-gate 	if (n > uiop->uio_resid)
243*0Sstevel@tonic-gate 		return;
244*0Sstevel@tonic-gate 	while (n != 0) {
245*0Sstevel@tonic-gate 		register iovec_t	*iovp = uiop->uio_iov;
246*0Sstevel@tonic-gate 		register size_t		niovb = MIN(iovp->iov_len, n);
247*0Sstevel@tonic-gate 
248*0Sstevel@tonic-gate 		if (niovb == 0) {
249*0Sstevel@tonic-gate 			uiop->uio_iov++;
250*0Sstevel@tonic-gate 			uiop->uio_iovcnt--;
251*0Sstevel@tonic-gate 			continue;
252*0Sstevel@tonic-gate 		}
253*0Sstevel@tonic-gate 		iovp->iov_base += niovb;
254*0Sstevel@tonic-gate 		uiop->uio_loffset += niovb;
255*0Sstevel@tonic-gate 		iovp->iov_len -= niovb;
256*0Sstevel@tonic-gate 		uiop->uio_resid -= niovb;
257*0Sstevel@tonic-gate 		n -= niovb;
258*0Sstevel@tonic-gate 	}
259*0Sstevel@tonic-gate }
260*0Sstevel@tonic-gate 
261*0Sstevel@tonic-gate /*
262*0Sstevel@tonic-gate  * Dup the suio into the duio and diovec of size diov_cnt. If diov
263*0Sstevel@tonic-gate  * is too small to dup suio then an error will be returned, else 0.
264*0Sstevel@tonic-gate  */
265*0Sstevel@tonic-gate int
266*0Sstevel@tonic-gate uiodup(uio_t *suio, uio_t *duio, iovec_t *diov, int diov_cnt)
267*0Sstevel@tonic-gate {
268*0Sstevel@tonic-gate 	int ix;
269*0Sstevel@tonic-gate 	iovec_t *siov = suio->uio_iov;
270*0Sstevel@tonic-gate 
271*0Sstevel@tonic-gate 	*duio = *suio;
272*0Sstevel@tonic-gate 	for (ix = 0; ix < suio->uio_iovcnt; ix++) {
273*0Sstevel@tonic-gate 		diov[ix] = siov[ix];
274*0Sstevel@tonic-gate 		if (ix >= diov_cnt)
275*0Sstevel@tonic-gate 			return (1);
276*0Sstevel@tonic-gate 	}
277*0Sstevel@tonic-gate 	duio->uio_iov = diov;
278*0Sstevel@tonic-gate 	return (0);
279*0Sstevel@tonic-gate }
280