xref: /dragonfly/sys/sys/uio.h (revision 23b3ef78)
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_ */
130