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kfifo.h revision 1.1 
      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