xref: /netbsd/sys/external/bsd/common/include/linux/gfp.h (revision 803fba05)
1 /*	$NetBSD: gfp.h,v 1.3 2021/12/19 11:03:32 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 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_GFP_H_
33 #define	_LINUX_GFP_H_
34 
35 /* GFP: `Get Free Page' */
36 
37 #include <sys/param.h>
38 #include <sys/cdefs.h>
39 
40 typedef int gfp_t;
41 
42 #define	GFP_ATOMIC	(__GFP_HIGH)
43 #define	GFP_DMA32	(__GFP_DMA32)
44 #define	GFP_HIGHUSER	(__GFP_FS | __GFP_HARDWALL | __GFP_HIGHMEM | \
45 			    __GFP_IO | __GFP_WAIT)
46 #define	GFP_KERNEL	(__GFP_FS | __GFP_IO | __GFP_WAIT)
47 #define	GFP_TEMPORARY	(__GFP_FS | __GFP_IO | __GFP_RECLAIMABLE | __GFP_WAIT)
48 #define	GFP_USER	(__GFP_FS | __GFP_HARDWALL | __GFP_IO | __GFP_WAIT)
49 
50 #define	GFP_NOWAIT	(GFP_ATOMIC & ~__GFP_HIGH)
51 
52 #define	__GFP_COMP		__BIT(0)
53 #define	__GFP_DMA32		__BIT(1)
54 #define	__GFP_FS		__BIT(2)
55 #define	__GFP_HARDWALL		__BIT(3)
56 #define	__GFP_HIGH		__BIT(4)
57 #define	__GFP_HIGHMEM		__BIT(5)
58 #define	__GFP_IO		__BIT(6)
59 #define	__GFP_NORETRY		__BIT(7)
60 #define	__GFP_NOWARN		__BIT(8)
61 #define	__GFP_NO_KSWAPD		__BIT(9)
62 #define	__GFP_RECLAIMABLE	__BIT(10)
63 #define	__GFP_WAIT		__BIT(11)
64 #define	__GFP_ZERO		__BIT(12)
65 
66 /*
67  * XXX Linux sez nobody should be using this in new code.  We never
68  * fail in the wait case anyway, so the point is moot.
69  */
70 #define	__GFP_NOFAIL		0
71 
72 /*
73  * Pretend these are the same.  __GFP_RETRY_MAYFAIL is supposed to do
74  * more than just __GFP_NORETRY, but should not hang forever like
75  * __GFP_WAIT.
76  */
77 #define	__GFP_RETRY_MAYFAIL	__GFP_NORETRY
78 
79 struct page;
80 
81 static inline bool
gfpflags_allow_blocking(gfp_t gfp)82 gfpflags_allow_blocking(gfp_t gfp)
83 {
84 	return (gfp & (__GFP_WAIT|__GFP_NORETRY)) == __GFP_WAIT;
85 }
86 
87 #endif	/* _LINUX_GFP_H_ */
88