bsd/sys/uio.h

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