1 /* $NetBSD: kern_subr.c,v 1.12 1994/06/29 06:32:43 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)kern_subr.c 8.3 (Berkeley) 1/21/94 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/proc.h> 46 #include <sys/malloc.h> 47 #include <sys/queue.h> 48 49 int 50 uiomove(cp, n, uio) 51 register caddr_t cp; 52 register int n; 53 register struct uio *uio; 54 { 55 register struct iovec *iov; 56 u_int cnt; 57 int error = 0; 58 59 #ifdef DIAGNOSTIC 60 if (uio->uio_rw != UIO_READ && uio->uio_rw != UIO_WRITE) 61 panic("uiomove: mode"); 62 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 63 panic("uiomove proc"); 64 #endif 65 while (n > 0 && uio->uio_resid) { 66 iov = uio->uio_iov; 67 cnt = iov->iov_len; 68 if (cnt == 0) { 69 uio->uio_iov++; 70 uio->uio_iovcnt--; 71 continue; 72 } 73 if (cnt > n) 74 cnt = n; 75 switch (uio->uio_segflg) { 76 77 case UIO_USERSPACE: 78 case UIO_USERISPACE: 79 if (uio->uio_rw == UIO_READ) 80 error = copyout(cp, iov->iov_base, cnt); 81 else 82 error = copyin(iov->iov_base, cp, cnt); 83 if (error) 84 return (error); 85 break; 86 87 case UIO_SYSSPACE: 88 if (uio->uio_rw == UIO_READ) 89 bcopy((caddr_t)cp, iov->iov_base, cnt); 90 else 91 bcopy(iov->iov_base, (caddr_t)cp, cnt); 92 break; 93 } 94 iov->iov_base += cnt; 95 iov->iov_len -= cnt; 96 uio->uio_resid -= cnt; 97 uio->uio_offset += cnt; 98 cp += cnt; 99 n -= cnt; 100 } 101 return (error); 102 } 103 104 /* 105 * Give next character to user as result of read. 106 */ 107 int 108 ureadc(c, uio) 109 register int c; 110 register struct uio *uio; 111 { 112 register struct iovec *iov; 113 114 if (uio->uio_resid <= 0) 115 panic("ureadc: non-positive resid"); 116 again: 117 if (uio->uio_iovcnt <= 0) 118 panic("ureadc: non-positive iovcnt"); 119 iov = uio->uio_iov; 120 if (iov->iov_len <= 0) { 121 uio->uio_iovcnt--; 122 uio->uio_iov++; 123 goto again; 124 } 125 switch (uio->uio_segflg) { 126 127 case UIO_USERSPACE: 128 if (subyte(iov->iov_base, c) < 0) 129 return (EFAULT); 130 break; 131 132 case UIO_SYSSPACE: 133 *iov->iov_base = c; 134 break; 135 136 case UIO_USERISPACE: 137 if (suibyte(iov->iov_base, c) < 0) 138 return (EFAULT); 139 break; 140 } 141 iov->iov_base++; 142 iov->iov_len--; 143 uio->uio_resid--; 144 uio->uio_offset++; 145 return (0); 146 } 147 148 #ifdef vax /* unused except by ct.c, other oddities XXX */ 149 /* 150 * Get next character written in by user from uio. 151 */ 152 int 153 uwritec(uio) 154 struct uio *uio; 155 { 156 register struct iovec *iov; 157 register int c; 158 159 if (uio->uio_resid <= 0) 160 return (-1); 161 again: 162 if (uio->uio_iovcnt <= 0) 163 panic("ureadc: non-positive iovcnt"); 164 iov = uio->uio_iov; 165 if (iov->iov_len == 0) { 166 uio->uio_iov++; 167 if (--uio->uio_iovcnt == 0) 168 return (-1); 169 goto again; 170 } 171 switch (uio->uio_segflg) { 172 173 case UIO_USERSPACE: 174 c = fubyte(iov->iov_base); 175 break; 176 177 case UIO_SYSSPACE: 178 c = *(u_char *) iov->iov_base; 179 break; 180 181 case UIO_USERISPACE: 182 c = fuibyte(iov->iov_base); 183 break; 184 } 185 if (c < 0) 186 return (-1); 187 iov->iov_base++; 188 iov->iov_len--; 189 uio->uio_resid--; 190 uio->uio_offset++; 191 return (c); 192 } 193 #endif /* vax */ 194 195 /* 196 * General routine to allocate a hash table. 197 */ 198 void * 199 hashinit(elements, type, hashmask) 200 int elements, type; 201 u_long *hashmask; 202 { 203 long hashsize; 204 LIST_HEAD(generic, generic) *hashtbl; 205 int i; 206 207 if (elements <= 0) 208 panic("hashinit: bad cnt"); 209 for (hashsize = 1; hashsize <= elements; hashsize <<= 1) 210 continue; 211 hashsize >>= 1; 212 hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK); 213 for (i = 0; i < hashsize; i++) 214 LIST_INIT(&hashtbl[i]); 215 *hashmask = hashsize - 1; 216 return (hashtbl); 217 } 218