uio.h
1 /* 2 * Copyright (c) 2000-2019 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ 29 /* 30 * Copyright (c) 1982, 1986, 1993, 1994 31 * The Regents of the University of California. All rights reserved. 32 * 33 * Redistribution and use in source and binary forms, with or without 34 * modification, are permitted provided that the following conditions 35 * are met: 36 * 1. Redistributions of source code must retain the above copyright 37 * notice, this list of conditions and the following disclaimer. 38 * 2. Redistributions in binary form must reproduce the above copyright 39 * notice, this list of conditions and the following disclaimer in the 40 * documentation and/or other materials provided with the distribution. 41 * 3. All advertising materials mentioning features or use of this software 42 * must display the following acknowledgement: 43 * This product includes software developed by the University of 44 * California, Berkeley and its contributors. 45 * 4. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)uio.h 8.5 (Berkeley) 2/22/94 62 */ 63 64 #ifndef _SYS_UIO_H_ 65 #define _SYS_UIO_H_ 66 67 #include <Availability.h> 68 #include <sys/cdefs.h> 69 #include <sys/_types.h> 70 #include <sys/_types/_off_t.h> 71 72 /* 73 * [XSI] The ssize_t and size_t types shall be defined as described 74 * in <sys/types.h>. 75 */ 76 #include <sys/_types/_size_t.h> 77 #include <sys/_types/_ssize_t.h> 78 79 /* 80 * [XSI] Structure whose address is passed as the second parameter to the 81 * readv(), preadv(), writev() and pwritev() functions. 82 */ 83 #include <sys/_types/_iovec_t.h> 84 85 86 #if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE) 87 /* 88 * IO direction for uio_t. 89 * UIO_READ - data moves into iovec(s) associated with uio_t 90 * UIO_WRITE - data moves out of iovec(s) associated with uio_t 91 */ 92 enum uio_rw { UIO_READ, UIO_WRITE }; 93 #endif 94 95 #ifdef KERNEL 96 97 /* 98 * XXX This all really wants a uio_internal.h 99 */ 100 101 #include <sys/kernel_types.h> 102 103 104 /* 105 * user / kernel address space type flags. 106 * WARNING - make sure to check when adding flags! Be sure new flags 107 * don't overlap the definitions in uio_internal.h 108 * NOTES - 109 * UIO_USERSPACE is equivalent to UIO_USERSPACE32, but UIO_USERSPACE32 110 * is preferred. UIO_USERSPACE remains for backwards compatibility. 111 * UIO_SYSSPACE is equivalent to UIO_SYSSPACE32, but UIO_SYSSPACE 112 * is preferred. 113 */ 114 enum uio_seg { 115 UIO_USERSPACE = 0, /* kernel address is virtual, to/from user virtual */ 116 UIO_SYSSPACE = 2, /* kernel address is virtual, to/from system virtual */ 117 UIO_USERSPACE32 = 5, /* kernel address is virtual, to/from user 32-bit virtual */ 118 UIO_USERSPACE64 = 8, /* kernel address is virtual, to/from user 64-bit virtual */ 119 UIO_SYSSPACE32 = 11 /* deprecated */ 120 }; 121 122 #define UIO_SEG_IS_USER_SPACE( a_uio_seg ) \ 123 ( (a_uio_seg) == UIO_USERSPACE64 || (a_uio_seg) == UIO_USERSPACE32 || \ 124 (a_uio_seg) == UIO_USERSPACE ) 125 126 127 __BEGIN_DECLS 128 129 /* 130 * uio_create - create an uio_t. 131 * Space is allocated to hold up to a_iovcount number of iovecs. The uio_t 132 * is not fully initialized until all iovecs are added using uio_addiov calls. 133 * a_iovcount is the maximum number of iovecs you may add. 134 */ 135 uio_t uio_create( int a_iovcount, /* max number of iovecs */ 136 off_t a_offset, /* current offset */ 137 int a_spacetype, /* type of address space */ 138 int a_iodirection ); /* read or write flag */ 139 140 /* 141 * uio_reset - reset an uio_t. 142 * Reset the given uio_t to initial values. The uio_t is not fully initialized 143 * until all iovecs are added using uio_add_ov calls. 144 * The a_iovcount value passed in the uio_create is the maximum number of 145 * iovecs you may add. 146 */ 147 void uio_reset( uio_t a_uio, 148 off_t a_offset, /* current offset */ 149 int a_spacetype, /* type of address space */ 150 int a_iodirection ); /* read or write flag */ 151 152 /* 153 * uio_duplicate - allocate a new uio and make a copy of the given uio_t. 154 * may return NULL. 155 */ 156 uio_t uio_duplicate( uio_t a_uio ); 157 158 159 /* 160 * uio_free - free a uio_t allocated via uio_create. 161 */ 162 void uio_free( uio_t a_uio ); 163 164 /* 165 * uio_addiov - add an iovec to the given uio_t. You may call this up to 166 * the a_iovcount number that was passed to uio_create. 167 * returns 0 if add was successful else non zero. 168 */ 169 int uio_addiov( uio_t a_uio, user_addr_t a_baseaddr, user_size_t a_length ); 170 171 /* 172 * uio_getiov - get iovec data associated with the given uio_t. Use 173 * a_index to iterate over each iovec (0 to (uio_iovcnt(uio_t) - 1)). 174 * a_baseaddr_p and a_length_p may be NULL. 175 * returns -1 when a_index is out of range or invalid uio_t. 176 * returns 0 when data is returned. 177 */ 178 int uio_getiov( uio_t a_uio, 179 int a_index, 180 user_addr_t * a_baseaddr_p, 181 user_size_t * a_length_p ); 182 183 /* 184 * uio_update - update the given uio_t for a_count of completed IO. 185 * This call adjusts decrements the current iovec length and residual IO, 186 * and increments the current iovec base address and offset value. 187 */ 188 void uio_update( uio_t a_uio, user_size_t a_count ); 189 190 /* 191 * uio_resid - return the residual IO value for the given uio_t 192 */ 193 user_ssize_t uio_resid( uio_t a_uio ); 194 195 /* 196 * uio_setresid - set the residual IO value for the given uio_t 197 */ 198 void uio_setresid( uio_t a_uio, user_ssize_t a_value ); 199 200 /* 201 * uio_iovcnt - return count of active iovecs for the given uio_t 202 */ 203 int uio_iovcnt( uio_t a_uio ); 204 205 /* 206 * uio_offset - return the current offset value for the given uio_t 207 */ 208 off_t uio_offset( uio_t a_uio ); 209 210 /* 211 * uio_setoffset - set the current offset value for the given uio_t 212 */ 213 void uio_setoffset( uio_t a_uio, off_t a_offset ); 214 215 /* 216 * uio_rw - return the read / write flag for the given uio_t 217 */ 218 int uio_rw( uio_t a_uio ); 219 220 /* 221 * uio_setrw - set the read / write flag for the given uio_t 222 */ 223 void uio_setrw( uio_t a_uio, int a_value ); 224 225 /* 226 * uio_isuserspace - return non zero value if the address space 227 * flag is for a user address space (could be 32 or 64 bit). 228 */ 229 int uio_isuserspace( uio_t a_uio ); 230 231 /* 232 * uio_curriovbase - return the base address of the current iovec associated 233 * with the given uio_t. May return 0. 234 */ 235 user_addr_t uio_curriovbase( uio_t a_uio ); 236 237 /* 238 * uio_curriovlen - return the length value of the current iovec associated 239 * with the given uio_t. 240 */ 241 user_size_t uio_curriovlen( uio_t a_uio ); 242 243 /* 244 * Limits 245 */ 246 #define UIO_MAXIOV 1024 /* max 1K of iov's */ 247 #define UIO_SMALLIOV 8 /* 8 on stack, else malloc */ 248 249 extern int uiomove(const char * cp, int n, struct uio *uio); 250 extern int uiomove64(const __uint64_t cp, int n, struct uio *uio); 251 __END_DECLS 252 253 #endif /* KERNEL */ 254 255 #ifndef KERNEL 256 257 __BEGIN_DECLS 258 ssize_t readv(int, const struct iovec *, int) __DARWIN_ALIAS_C(readv); 259 ssize_t writev(int, const struct iovec *, int) __DARWIN_ALIAS_C(writev); 260 261 #if (!defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE)) || defined(_DARWIN_C_SOURCE) 262 263 ssize_t preadv(int, const struct iovec *, int, off_t) __DARWIN_NOCANCEL(preadv) __API_AVAILABLE(macos(10.16), ios(14.0), watchos(7.0), tvos(14.0)); 264 ssize_t pwritev(int, const struct iovec *, int, off_t) __DARWIN_NOCANCEL(pwritev) __API_AVAILABLE(macos(10.16), ios(14.0), watchos(7.0), tvos(14.0)); 265 266 #endif /* #if (!defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE)) || defined(_DARWIN_C_SOURCE) */ 267 268 __END_DECLS 269 270 #endif /* !KERNEL */ 271 272 #endif /* !_SYS_UIO_H_ */