sys/sys/uio.h

   1 /*
   2  * Copyright (c) 1982, 1986, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)uio.h       8.5 (Berkeley) 2/22/94
  30  * $FreeBSD: src/sys/sys/uio.h,v 1.11.2.1 2001/09/28 16:58:35 dillon Exp $
  31  */
  32
  33 #ifndef _SYS_UIO_H_
  34 #define _SYS_UIO_H_
  35
  36 #include <sys/_iovec.h>
  37
  38 #ifndef _SYS_TYPES_H_
  39 #include <sys/types.h>
  40 #endif
  41 #ifndef _SYS_PARAM_H_
  42 #include <sys/param.h>
  43 #endif
  44 #ifndef _SYS_MALLOC_H_
  45 #include <sys/malloc.h>         /* Needed to inline iovec_free(). */
  46 #endif
  47
  48 enum    uio_rw { UIO_READ, UIO_WRITE };
  49
  50 /* Segment flag values. */
  51 enum uio_seg {
  52         UIO_USERSPACE,          /* from user data space */
  53         UIO_SYSSPACE,           /* from system space */
  54         UIO_NOCOPY              /* don't copy, already in object */
  55 };
  56
  57 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
  58
  59 /*
  60  * uio_td is primarily used for USERSPACE transfers, but some devices
  61  * like ttys may also use it to get at the process.
  62  *
  63  * NOTE: uio_resid: Previously used int and FreeBSD decided to use ssize_t,
  64  *       but after reviewing use cases and in particular the fact that the
  65  *       iov uses an unsigned quantity, DragonFly will use the (unsigned)
  66  *       size_t.
  67  */
  68 struct buf;
  69
  70 struct uio {
  71         struct  iovec *uio_iov;
  72         int     uio_iovcnt;
  73         off_t   uio_offset;
  74         size_t  uio_resid;
  75         enum    uio_seg uio_segflg;
  76         enum    uio_rw uio_rw;
  77         struct  thread *uio_td;
  78 };
  79
  80 /*
  81  * Limits
  82  */
  83 #define UIO_MAXIOV      1024            /* max 1K of iov's */
  84 #define UIO_SMALLIOV    8               /* 8 on stack, else malloc */
  85
  86 #endif
  87
  88 #if defined(_KERNEL)
  89
  90 struct vm_object;
  91 struct vm_page;
  92
  93 int     uiomove (caddr_t, size_t, struct uio *);
  94 int     uiomove_nofault (caddr_t, size_t, struct uio *);
  95 int     uiomovebp (struct buf *, caddr_t, size_t, struct uio *);
  96 int     uiomovez (size_t, struct uio *);
  97 int     uiomove_frombuf (void *buf, size_t buflen, struct uio *uio);
  98 int     uiomove_fromphys(struct vm_page *ma[], vm_offset_t offset,
  99                             size_t n, struct uio *uio);
 100 int     uioread (int, struct uio *, struct vm_object *, int *);
 101 int     iovec_copyin(struct iovec *, struct iovec **, struct iovec *,
 102                             size_t, size_t *);
 103
 104 /*
 105  * MPSAFE
 106  */
 107 static __inline void
 108 iovec_free(struct iovec **kiov, struct iovec *siov)
 109 {
 110         if (*kiov != siov) {
 111                 kfree(*kiov, M_IOV);
 112                 *kiov = NULL;
 113         }
 114 }
 115
 116 #else /* !_KERNEL */
 117
 118 #include <sys/cdefs.h>
 119
 120 __BEGIN_DECLS
 121 ssize_t readv(int, const struct iovec *, int);
 122 ssize_t writev(int, const struct iovec *, int);
 123 ssize_t preadv(int, const struct iovec *, int, off_t);
 124 ssize_t pwritev(int, const struct iovec *, int, off_t);
 125 __END_DECLS
 126
 127 #endif /* _KERNEL */
 128
 129 #endif /* !_SYS_UIO_H_ */