xref: /netbsd-src/sys/external/bsd/drm2/include/linux/kfifo.h (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: kfifo.h,v 1.1 2014/07/16 20:56:25 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Taylor R. Campbell.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef	_LINUX_KFIFO_H_
33 #define	_LINUX_KFIFO_H_
34 
35 #include <sys/pcq.h>
36 
37 #define	DECLARE_KFIFO_PTR(fifo, type)					      \
38 	struct {							      \
39 		pcq_t	*pcq;						      \
40 		type	*dummy;						      \
41 	} fifo
42 
43 #define	kfifo_put(fifo, item)						      \
44 	pcq_put((fifo)->pcq, __UNCONST((const char *)(item) +		      \
45 		0*sizeof((item) == *(fifo)->dummy)))
46 #define	kfifo_get(fifo, itemp)						      \
47 	((*((itemp) + 0*sizeof((itemp) - (fifo)->dummy)) =		      \
48 	    pcq_get((fifo)->pcq)) != NULL)
49 
50 #define	kfifo_is_empty(fifo)						      \
51 	(pcq_peek((fifo)->pcq) == NULL)
52 
53 #define	kfifo_alloc(fifo, size, gfp)					      \
54 	(((fifo)->pcq = pcq_create((size),				      \
55 		ISSET((gfp), __GFP_WAIT)? KM_SLEEP : KM_NOSLEEP))	      \
56 	    == NULL? -ENOMEM : 0)
57 
58 #define	kfifo_free(fifo)						      \
59 	pcq_destroy((fifo)->pcq)
60 
61 #endif	/* _LINUX_KFIFO_H_ */
62