bsd/sys/uio.h

   1 /*
   2  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  31 /*
  32  * Copyright (c) 1982, 1986, 1993, 1994
  33  *      The Regents of the University of California.  All rights reserved.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  *
  63  *      @(#)uio.h       8.5 (Berkeley) 2/22/94
  64  */
  65
  66 #ifndef _SYS_UIO_H_
  67 #define _SYS_UIO_H_
  68
  69 #include <sys/cdefs.h>
  70 #include <sys/_types.h>
  71
  72 /*
  73  * [XSI] The ssize_t and size_t types shall be defined as described
  74  * in <sys/types.h>.
  75  */
  76 #ifndef _SIZE_T
  77 #define _SIZE_T
  78 typedef __darwin_size_t         size_t;
  79 #endif
  80
  81 #ifndef _SSIZE_T
  82 #define _SSIZE_T
  83 typedef __darwin_ssize_t        ssize_t;
  84 #endif
  85
  86 /*
  87  * [XSI] Structure whose address is passed as the second parameter to the
  88  * readv() and writev() functions.
  89  */
  90 #ifndef _STRUCT_IOVEC
  91 #define _STRUCT_IOVEC
  92 struct iovec {
  93         void *   iov_base;      /* [XSI] Base address of I/O memory region */
  94         size_t   iov_len;       /* [XSI] Size of region iov_base points to */
  95 };
  96 #endif
  97
  98
  99 #ifndef _POSIX_C_SOURCE
 100 /*
 101  * IO direction for uio_t.
 102  *      UIO_READ - data moves into iovec(s) associated with uio_t
 103  *      UIO_WRITE - data moves out of iovec(s) associated with uio_t
 104  */
 105 enum uio_rw { UIO_READ, UIO_WRITE };
 106 #endif
 107
 108 #ifdef KERNEL
 109
 110 /*
 111  * XXX This all really wants a uio_internal.h
 112  */
 113
 114 #include <sys/kernel_types.h>
 115
 116
 117 /*
 118  * user / kernel address space type flags.
 119  * WARNING - make sure to check when adding flags!  Be sure new flags
 120  * don't overlap the definitions in uio_internal.h
 121  * NOTES -
 122  *      UIO_USERSPACE is equivalent to UIO_USERSPACE32, but UIO_USERSPACE32
 123  *              is preferred.  UIO_USERSPACE remains for backwards compatibility.
 124  *      UIO_SYSSPACE is equivalent to UIO_SYSSPACE32, but UIO_SYSSPACE32
 125  *              is preferred.  UIO_SYSSPACE remains for backwards compatibility.
 126  */
 127 enum uio_seg {
 128         UIO_USERSPACE           = 0,    /* kernel address is virtual,  to/from user virtual */
 129         UIO_SYSSPACE            = 2,    /* kernel address is virtual,  to/from system virtual */
 130         UIO_USERSPACE32         = 5,    /* kernel address is virtual,  to/from user 32-bit virtual */
 131         UIO_USERSPACE64         = 8,    /* kernel address is virtual,  to/from user 64-bit virtual */
 132         UIO_SYSSPACE32          = 11    /* kernel address is virtual,  to/from system virtual */
 133 };
 134
 135 #define UIO_SEG_IS_USER_SPACE( a_uio_seg )  \
 136         ( (a_uio_seg) == UIO_USERSPACE64 || (a_uio_seg) == UIO_USERSPACE32 || \
 137           (a_uio_seg) == UIO_USERSPACE )
 138
 139
 140 __BEGIN_DECLS
 141
 142 /*
 143  * uio_create - create an uio_t.
 144  *      Space is allocated to hold up to a_iovcount number of iovecs.  The uio_t
 145  *      is not fully initialized until all iovecs are added using uio_addiov calls.
 146  *      a_iovcount is the maximum number of iovecs you may add.
 147  */
 148 uio_t uio_create( int a_iovcount,               /* max number of iovecs */
 149                                   off_t a_offset,               /* current offset */
 150                                   int a_spacetype,              /* type of address space */
 151                                   int a_iodirection );  /* read or write flag */
 152
 153 /*
 154  * uio_reset - reset an uio_t.
 155  *      Reset the given uio_t to initial values.  The uio_t is not fully initialized
 156  *      until all iovecs are added using uio_add_ov calls.
 157  *      The a_iovcount value passed in the uio_create is the maximum number of
 158  *      iovecs you may add.
 159  */
 160 void uio_reset( uio_t a_uio,
 161                                 off_t a_offset,                 /* current offset */
 162                                 int a_spacetype,                /* type of address space */
 163                                 int a_iodirection );    /* read or write flag */
 164
 165 /*
 166  * uio_duplicate - allocate a new uio and make a copy of the given uio_t.
 167  *      may return NULL.
 168  */
 169 uio_t uio_duplicate( uio_t a_uio );
 170
 171
 172 /*
 173  * uio_free - free a uio_t allocated via uio_create.
 174  */
 175 void uio_free( uio_t a_uio );
 176
 177 /*
 178  * uio_addiov - add an iovec to the given uio_t.  You may call this up to
 179  *      the a_iovcount number that was passed to uio_create.
 180  *      returns 0 if add was successful else non zero.
 181  */
 182 int uio_addiov( uio_t a_uio, user_addr_t a_baseaddr, user_size_t a_length );
 183
 184 /*
 185  * uio_getiov - get iovec data associated with the given uio_t.  Use
 186  *  a_index to iterate over each iovec (0 to (uio_iovcnt(uio_t) - 1)).
 187  *  a_baseaddr_p and a_length_p may be NULL.
 188  *      returns -1 when a_index is out of range or invalid uio_t.
 189  *      returns 0 when data is returned.
 190  */
 191 int uio_getiov( uio_t a_uio,
 192                  int a_index,
 193                  user_addr_t * a_baseaddr_p,
 194                  user_size_t * a_length_p );
 195
 196 /*
 197  * uio_update - update the given uio_t for a_count of completed IO.
 198  *      This call adjusts decrements the current iovec length and residual IO,
 199  *      and increments the current iovec base address and offset value.
 200  */
 201 void uio_update( uio_t a_uio, user_size_t a_count );
 202
 203 /*
 204  * uio_resid - return the residual IO value for the given uio_t
 205  */
 206 user_ssize_t uio_resid( uio_t a_uio );
 207
 208 /*
 209  * uio_setresid - set the residual IO value for the given uio_t
 210  */
 211 void uio_setresid( uio_t a_uio, user_ssize_t a_value );
 212
 213 /*
 214  * uio_iovcnt - return count of active iovecs for the given uio_t
 215  */
 216 int uio_iovcnt( uio_t a_uio );
 217
 218 /*
 219  * uio_offset - return the current offset value for the given uio_t
 220  */
 221 off_t uio_offset( uio_t a_uio );
 222
 223 /*
 224  * uio_setoffset - set the current offset value for the given uio_t
 225  */
 226 void uio_setoffset( uio_t a_uio, off_t a_offset );
 227
 228 /*
 229  * uio_rw - return the read / write flag for the given uio_t
 230  */
 231 int uio_rw( uio_t a_uio );
 232
 233 /*
 234  * uio_setrw - set the read / write flag for the given uio_t
 235  */
 236 void uio_setrw( uio_t a_uio, int a_value );
 237
 238 /*
 239  * uio_isuserspace - return non zero value if the address space
 240  * flag is for a user address space (could be 32 or 64 bit).
 241  */
 242 int uio_isuserspace( uio_t a_uio );
 243
 244 /*
 245  * uio_curriovbase - return the base address of the current iovec associated
 246  *      with the given uio_t.  May return 0.
 247  */
 248 user_addr_t uio_curriovbase( uio_t a_uio );
 249
 250 /*
 251  * uio_curriovlen - return the length value of the current iovec associated
 252  *      with the given uio_t.
 253  */
 254 user_size_t uio_curriovlen( uio_t a_uio );
 255
 256 /*
 257  * Limits
 258  */
 259 #define UIO_MAXIOV      1024            /* max 1K of iov's */
 260 #define UIO_SMALLIOV    8               /* 8 on stack, else malloc */
 261
 262 extern int uiomove(caddr_t cp, int n, struct uio *uio);
 263 extern int uiomove64(unsigned long long cp, int n, struct uio *uio);
 264 extern int ureadc(int c, struct uio *uio);
 265 extern int uwritec(struct uio *uio);
 266 __END_DECLS
 267
 268 #endif /* KERNEL */
 269
 270 #ifndef KERNEL
 271
 272 __BEGIN_DECLS
 273 ssize_t readv(int, const struct iovec *, int);
 274 ssize_t writev(int, const struct iovec *, int);
 275 __END_DECLS
 276 #endif /* !KERNEL */
 277
 278 #endif /* !_SYS_UIO_H_ */