1 /* 2 * Copyright (c) 1982, 1986, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: @(#)kern_subr.c 8.3 (Berkeley) 1/21/94 39 * $Id: kern_subr.c,v 1.11 1994/05/18 12:46:29 mycroft Exp $ 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/proc.h> 45 #include <sys/malloc.h> 46 #include <sys/queue.h> 47 48 int 49 uiomove(cp, n, uio) 50 register caddr_t cp; 51 register int n; 52 register struct uio *uio; 53 { 54 register struct iovec *iov; 55 u_int cnt; 56 int error = 0; 57 58 #ifdef DIAGNOSTIC 59 if (uio->uio_rw != UIO_READ && uio->uio_rw != UIO_WRITE) 60 panic("uiomove: mode"); 61 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 62 panic("uiomove proc"); 63 #endif 64 while (n > 0 && uio->uio_resid) { 65 iov = uio->uio_iov; 66 cnt = iov->iov_len; 67 if (cnt == 0) { 68 uio->uio_iov++; 69 uio->uio_iovcnt--; 70 continue; 71 } 72 if (cnt > n) 73 cnt = n; 74 switch (uio->uio_segflg) { 75 76 case UIO_USERSPACE: 77 case UIO_USERISPACE: 78 if (uio->uio_rw == UIO_READ) 79 error = copyout(cp, iov->iov_base, cnt); 80 else 81 error = copyin(iov->iov_base, cp, cnt); 82 if (error) 83 return (error); 84 break; 85 86 case UIO_SYSSPACE: 87 if (uio->uio_rw == UIO_READ) 88 bcopy((caddr_t)cp, iov->iov_base, cnt); 89 else 90 bcopy(iov->iov_base, (caddr_t)cp, cnt); 91 break; 92 } 93 iov->iov_base += cnt; 94 iov->iov_len -= cnt; 95 uio->uio_resid -= cnt; 96 uio->uio_offset += cnt; 97 cp += cnt; 98 n -= cnt; 99 } 100 return (error); 101 } 102 103 /* 104 * Give next character to user as result of read. 105 */ 106 int 107 ureadc(c, uio) 108 register int c; 109 register struct uio *uio; 110 { 111 register struct iovec *iov; 112 113 if (uio->uio_resid <= 0) 114 panic("ureadc: non-positive resid"); 115 again: 116 if (uio->uio_iovcnt <= 0) 117 panic("ureadc: non-positive iovcnt"); 118 iov = uio->uio_iov; 119 if (iov->iov_len <= 0) { 120 uio->uio_iovcnt--; 121 uio->uio_iov++; 122 goto again; 123 } 124 switch (uio->uio_segflg) { 125 126 case UIO_USERSPACE: 127 if (subyte(iov->iov_base, c) < 0) 128 return (EFAULT); 129 break; 130 131 case UIO_SYSSPACE: 132 *iov->iov_base = c; 133 break; 134 135 case UIO_USERISPACE: 136 if (suibyte(iov->iov_base, c) < 0) 137 return (EFAULT); 138 break; 139 } 140 iov->iov_base++; 141 iov->iov_len--; 142 uio->uio_resid--; 143 uio->uio_offset++; 144 return (0); 145 } 146 147 #ifdef vax /* unused except by ct.c, other oddities XXX */ 148 /* 149 * Get next character written in by user from uio. 150 */ 151 int 152 uwritec(uio) 153 struct uio *uio; 154 { 155 register struct iovec *iov; 156 register int c; 157 158 if (uio->uio_resid <= 0) 159 return (-1); 160 again: 161 if (uio->uio_iovcnt <= 0) 162 panic("ureadc: non-positive iovcnt"); 163 iov = uio->uio_iov; 164 if (iov->iov_len == 0) { 165 uio->uio_iov++; 166 if (--uio->uio_iovcnt == 0) 167 return (-1); 168 goto again; 169 } 170 switch (uio->uio_segflg) { 171 172 case UIO_USERSPACE: 173 c = fubyte(iov->iov_base); 174 break; 175 176 case UIO_SYSSPACE: 177 c = *(u_char *) iov->iov_base; 178 break; 179 180 case UIO_USERISPACE: 181 c = fuibyte(iov->iov_base); 182 break; 183 } 184 if (c < 0) 185 return (-1); 186 iov->iov_base++; 187 iov->iov_len--; 188 uio->uio_resid--; 189 uio->uio_offset++; 190 return (c); 191 } 192 #endif /* vax */ 193 194 /* 195 * General routine to allocate a hash table. 196 */ 197 void * 198 hashinit(elements, type, hashmask) 199 int elements, type; 200 u_long *hashmask; 201 { 202 long hashsize; 203 LIST_HEAD(generic, generic) *hashtbl; 204 int i; 205 206 if (elements <= 0) 207 panic("hashinit: bad cnt"); 208 for (hashsize = 1; hashsize <= elements; hashsize <<= 1) 209 continue; 210 hashsize >>= 1; 211 hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK); 212 for (i = 0; i < hashsize; i++) 213 LIST_INIT(&hashtbl[i]); 214 *hashmask = hashsize - 1; 215 return (hashtbl); 216 } 217