bsd/sys/uio.h

   1 /*
   2  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  23 /*
  24  * Copyright (c) 1982, 1986, 1993, 1994
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * Redistribution and use in source and binary forms, with or without
  28  * modification, are permitted provided that the following conditions
  29  * are met:
  30  * 1. Redistributions of source code must retain the above copyright
  31  *    notice, this list of conditions and the following disclaimer.
  32  * 2. Redistributions in binary form must reproduce the above copyright
  33  *    notice, this list of conditions and the following disclaimer in the
  34  *    documentation and/or other materials provided with the distribution.
  35  * 3. All advertising materials mentioning features or use of this software
  36  *    must display the following acknowledgement:
  37  *      This product includes software developed by the University of
  38  *      California, Berkeley and its contributors.
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  *
  55  *      @(#)uio.h       8.5 (Berkeley) 2/22/94
  56  */
  57
  58 #ifndef _SYS_UIO_H_
  59 #define _SYS_UIO_H_
  60
  61 #include <sys/cdefs.h>
  62 #include <sys/_types.h>
  63
  64 /*
  65  * [XSI] The ssize_t and size_t types shall be defined as described
  66  * in <sys/types.h>.
  67  */
  68 #ifndef _SIZE_T
  69 #define _SIZE_T
  70 typedef __darwin_size_t         size_t;
  71 #endif
  72
  73 #ifndef _SSIZE_T
  74 #define _SSIZE_T
  75 typedef __darwin_ssize_t        ssize_t;
  76 #endif
  77
  78 /*
  79  * [XSI] Structure whose address is passed as the second parameter to the
  80  * readv() and writev() functions.
  81  */
  82 #ifndef _STRUCT_IOVEC
  83 #define _STRUCT_IOVEC
  84 struct iovec {
  85         void *   iov_base;      /* [XSI] Base address of I/O memory region */
  86         size_t   iov_len;       /* [XSI] Size of region iov_base points to */
  87 };
  88 #endif
  89
  90
  91 #ifndef _POSIX_C_SOURCE
  92 /*
  93  * IO direction for uio_t.
  94  *      UIO_READ - data moves into iovec(s) associated with uio_t
  95  *      UIO_WRITE - data moves out of iovec(s) associated with uio_t
  96  */
  97 enum uio_rw { UIO_READ, UIO_WRITE };
  98 #endif
  99
 100 #ifdef KERNEL
 101
 102 /*
 103  * XXX This all really wants a uio_internal.h
 104  */
 105
 106 #include <sys/kernel_types.h>
 107
 108
 109 /*
 110  * user / kernel address space type flags.
 111  * WARNING - make sure to check when adding flags!  Be sure new flags
 112  * don't overlap the definitions in uio_internal.h
 113  * NOTES -
 114  *      UIO_USERSPACE is equivalent to UIO_USERSPACE32, but UIO_USERSPACE32
 115  *              is preferred.  UIO_USERSPACE remains for backwards compatibility.
 116  *      UIO_SYSSPACE is equivalent to UIO_SYSSPACE32, but UIO_SYSSPACE32
 117  *              is preferred.  UIO_SYSSPACE remains for backwards compatibility.
 118  */
 119 enum uio_seg {
 120         UIO_USERSPACE           = 0,    /* kernel address is virtual,  to/from user virtual */
 121         UIO_SYSSPACE            = 2,    /* kernel address is virtual,  to/from system virtual */
 122         UIO_USERSPACE32         = 5,    /* kernel address is virtual,  to/from user 32-bit virtual */
 123         UIO_USERSPACE64         = 8,    /* kernel address is virtual,  to/from user 64-bit virtual */
 124         UIO_SYSSPACE32          = 11    /* kernel address is virtual,  to/from system virtual */
 125 };
 126
 127 #define UIO_SEG_IS_USER_SPACE( a_uio_seg )  \
 128         ( (a_uio_seg) == UIO_USERSPACE64 || (a_uio_seg) == UIO_USERSPACE32 || \
 129           (a_uio_seg) == UIO_USERSPACE )
 130
 131
 132 __BEGIN_DECLS
 133
 134 /*
 135  * uio_create - create an uio_t.
 136  *      Space is allocated to hold up to a_iovcount number of iovecs.  The uio_t
 137  *      is not fully initialized until all iovecs are added using uio_addiov calls.
 138  *      a_iovcount is the maximum number of iovecs you may add.
 139  */
 140 uio_t uio_create( int a_iovcount,               /* max number of iovecs */
 141                                   off_t a_offset,               /* current offset */
 142                                   int a_spacetype,              /* type of address space */
 143                                   int a_iodirection );  /* read or write flag */
 144
 145 /*
 146  * uio_reset - reset an uio_t.
 147  *      Reset the given uio_t to initial values.  The uio_t is not fully initialized
 148  *      until all iovecs are added using uio_add_ov calls.
 149  *      The a_iovcount value passed in the uio_create is the maximum number of
 150  *      iovecs you may add.
 151  */
 152 void uio_reset( uio_t a_uio,
 153                                 off_t a_offset,                 /* current offset */
 154                                 int a_spacetype,                /* type of address space */
 155                                 int a_iodirection );    /* read or write flag */
 156
 157 /*
 158  * uio_duplicate - allocate a new uio and make a copy of the given uio_t.
 159  *      may return NULL.
 160  */
 161 uio_t uio_duplicate( uio_t a_uio );
 162
 163
 164 /*
 165  * uio_free - free a uio_t allocated via uio_create.
 166  */
 167 void uio_free( uio_t a_uio );
 168
 169 /*
 170  * uio_addiov - add an iovec to the given uio_t.  You may call this up to
 171  *      the a_iovcount number that was passed to uio_create.
 172  *      returns 0 if add was successful else non zero.
 173  */
 174 int uio_addiov( uio_t a_uio, user_addr_t a_baseaddr, user_size_t a_length );
 175
 176 /*
 177  * uio_getiov - get iovec data associated with the given uio_t.  Use
 178  *  a_index to iterate over each iovec (0 to (uio_iovcnt(uio_t) - 1)).
 179  *  a_baseaddr_p and a_length_p may be NULL.
 180  *      returns -1 when a_index is out of range or invalid uio_t.
 181  *      returns 0 when data is returned.
 182  */
 183 int uio_getiov( uio_t a_uio,
 184                  int a_index,
 185                  user_addr_t * a_baseaddr_p,
 186                  user_size_t * a_length_p );
 187
 188 /*
 189  * uio_update - update the given uio_t for a_count of completed IO.
 190  *      This call adjusts decrements the current iovec length and residual IO,
 191  *      and increments the current iovec base address and offset value.
 192  */
 193 void uio_update( uio_t a_uio, user_size_t a_count );
 194
 195 /*
 196  * uio_resid - return the residual IO value for the given uio_t
 197  */
 198 user_ssize_t uio_resid( uio_t a_uio );
 199
 200 /*
 201  * uio_setresid - set the residual IO value for the given uio_t
 202  */
 203 void uio_setresid( uio_t a_uio, user_ssize_t a_value );
 204
 205 /*
 206  * uio_iovcnt - return count of active iovecs for the given uio_t
 207  */
 208 int uio_iovcnt( uio_t a_uio );
 209
 210 /*
 211  * uio_offset - return the current offset value for the given uio_t
 212  */
 213 off_t uio_offset( uio_t a_uio );
 214
 215 /*
 216  * uio_setoffset - set the current offset value for the given uio_t
 217  */
 218 void uio_setoffset( uio_t a_uio, off_t a_offset );
 219
 220 /*
 221  * uio_rw - return the read / write flag for the given uio_t
 222  */
 223 int uio_rw( uio_t a_uio );
 224
 225 /*
 226  * uio_setrw - set the read / write flag for the given uio_t
 227  */
 228 void uio_setrw( uio_t a_uio, int a_value );
 229
 230 /*
 231  * uio_isuserspace - return non zero value if the address space
 232  * flag is for a user address space (could be 32 or 64 bit).
 233  */
 234 int uio_isuserspace( uio_t a_uio );
 235
 236 /*
 237  * uio_curriovbase - return the base address of the current iovec associated
 238  *      with the given uio_t.  May return 0.
 239  */
 240 user_addr_t uio_curriovbase( uio_t a_uio );
 241
 242 /*
 243  * uio_curriovlen - return the length value of the current iovec associated
 244  *      with the given uio_t.
 245  */
 246 user_size_t uio_curriovlen( uio_t a_uio );
 247
 248 /*
 249  * Limits
 250  */
 251 #define UIO_MAXIOV      1024            /* max 1K of iov's */
 252 #define UIO_SMALLIOV    8               /* 8 on stack, else malloc */
 253
 254 extern int uiomove(caddr_t cp, int n, struct uio *uio);
 255 extern int uiomove64(unsigned long long cp, int n, struct uio *uio);
 256 extern int ureadc(int c, struct uio *uio);
 257 extern int uwritec(struct uio *uio);
 258 __END_DECLS
 259
 260 #endif /* KERNEL */
 261
 262 #ifndef KERNEL
 263
 264 __BEGIN_DECLS
 265 ssize_t readv(int, const struct iovec *, int);
 266 ssize_t writev(int, const struct iovec *, int);
 267 __END_DECLS
 268 #endif /* !KERNEL */
 269
 270 #endif /* !_SYS_UIO_H_ */