xref: /openbmc/linux/fs/xfs/kmem.h (revision bc05aa6e)
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #ifndef __XFS_SUPPORT_KMEM_H__
19 #define __XFS_SUPPORT_KMEM_H__
20 
21 #include <linux/slab.h>
22 #include <linux/sched.h>
23 #include <linux/mm.h>
24 #include <linux/vmalloc.h>
25 
26 /*
27  * General memory allocation interfaces
28  */
29 
30 typedef unsigned __bitwise xfs_km_flags_t;
31 #define KM_SLEEP	((__force xfs_km_flags_t)0x0001u)
32 #define KM_NOSLEEP	((__force xfs_km_flags_t)0x0002u)
33 #define KM_NOFS		((__force xfs_km_flags_t)0x0004u)
34 #define KM_MAYFAIL	((__force xfs_km_flags_t)0x0008u)
35 #define KM_ZERO		((__force xfs_km_flags_t)0x0010u)
36 
37 /*
38  * We use a special process flag to avoid recursive callbacks into
39  * the filesystem during transactions.  We will also issue our own
40  * warnings, so we explicitly skip any generic ones (silly of us).
41  */
42 static inline gfp_t
43 kmem_flags_convert(xfs_km_flags_t flags)
44 {
45 	gfp_t	lflags;
46 
47 	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL|KM_ZERO));
48 
49 	if (flags & KM_NOSLEEP) {
50 		lflags = GFP_ATOMIC | __GFP_NOWARN;
51 	} else {
52 		lflags = GFP_KERNEL | __GFP_NOWARN;
53 		if (flags & KM_NOFS)
54 			lflags &= ~__GFP_FS;
55 	}
56 
57 	/*
58 	 * Default page/slab allocator behavior is to retry for ever
59 	 * for small allocations. We can override this behavior by using
60 	 * __GFP_RETRY_MAYFAIL which will tell the allocator to retry as long
61 	 * as it is feasible but rather fail than retry forever for all
62 	 * request sizes.
63 	 */
64 	if (flags & KM_MAYFAIL)
65 		lflags |= __GFP_RETRY_MAYFAIL;
66 
67 	if (flags & KM_ZERO)
68 		lflags |= __GFP_ZERO;
69 
70 	return lflags;
71 }
72 
73 extern void *kmem_alloc(size_t, xfs_km_flags_t);
74 extern void *kmem_zalloc_large(size_t size, xfs_km_flags_t);
75 extern void *kmem_realloc(const void *, size_t, xfs_km_flags_t);
76 static inline void  kmem_free(const void *ptr)
77 {
78 	kvfree(ptr);
79 }
80 
81 
82 static inline void *
83 kmem_zalloc(size_t size, xfs_km_flags_t flags)
84 {
85 	return kmem_alloc(size, flags | KM_ZERO);
86 }
87 
88 /*
89  * Zone interfaces
90  */
91 
92 #define KM_ZONE_HWALIGN	SLAB_HWCACHE_ALIGN
93 #define KM_ZONE_RECLAIM	SLAB_RECLAIM_ACCOUNT
94 #define KM_ZONE_SPREAD	SLAB_MEM_SPREAD
95 #define KM_ZONE_ACCOUNT	SLAB_ACCOUNT
96 
97 #define kmem_zone	kmem_cache
98 #define kmem_zone_t	struct kmem_cache
99 
100 static inline kmem_zone_t *
101 kmem_zone_init(int size, char *zone_name)
102 {
103 	return kmem_cache_create(zone_name, size, 0, 0, NULL);
104 }
105 
106 static inline kmem_zone_t *
107 kmem_zone_init_flags(int size, char *zone_name, slab_flags_t flags,
108 		     void (*construct)(void *))
109 {
110 	return kmem_cache_create(zone_name, size, 0, flags, construct);
111 }
112 
113 static inline void
114 kmem_zone_free(kmem_zone_t *zone, void *ptr)
115 {
116 	kmem_cache_free(zone, ptr);
117 }
118 
119 static inline void
120 kmem_zone_destroy(kmem_zone_t *zone)
121 {
122 	kmem_cache_destroy(zone);
123 }
124 
125 extern void *kmem_zone_alloc(kmem_zone_t *, xfs_km_flags_t);
126 
127 static inline void *
128 kmem_zone_zalloc(kmem_zone_t *zone, xfs_km_flags_t flags)
129 {
130 	return kmem_zone_alloc(zone, flags | KM_ZERO);
131 }
132 
133 #endif /* __XFS_SUPPORT_KMEM_H__ */
134