summaryrefslogtreecommitdiffstats
path: root/fs/xfs/linux-2.6/kmem.h
blob: f0268a84e6fd8dcb38b2cbf1bf3b3792a54563b8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_SUPPORT_KMEM_H__
#define __XFS_SUPPORT_KMEM_H__

#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mm.h>

/*
 * Process flags handling
 */

#define PFLAGS_TEST_NOIO()              (current->flags & PF_NOIO)
#define PFLAGS_TEST_FSTRANS()           (current->flags & PF_FSTRANS)

#define PFLAGS_SET_NOIO() do {		\
	current->flags |= PF_NOIO;	\
} while (0)

#define PFLAGS_CLEAR_NOIO() do {	\
	current->flags &= ~PF_NOIO;	\
} while (0)

/* these could be nested, so we save state */
#define PFLAGS_SET_FSTRANS(STATEP) do {	\
	*(STATEP) = current->flags;	\
	current->flags |= PF_FSTRANS;	\
} while (0)

#define PFLAGS_CLEAR_FSTRANS(STATEP) do { \
	*(STATEP) = current->flags;	\
	current->flags &= ~PF_FSTRANS;	\
} while (0)

/* Restore the PF_FSTRANS state to what was saved in STATEP */
#define PFLAGS_RESTORE_FSTRANS(STATEP) do {     		\
	current->flags = ((current->flags & ~PF_FSTRANS) |	\
			  (*(STATEP) & PF_FSTRANS));		\
} while (0)

#define PFLAGS_DUP(OSTATEP, NSTATEP) do { \
	*(NSTATEP) = *(OSTATEP);	\
} while (0)

/*
 * General memory allocation interfaces
 */

#define KM_SLEEP	0x0001u
#define KM_NOSLEEP	0x0002u
#define KM_NOFS		0x0004u
#define KM_MAYFAIL	0x0008u

/*
 * We use a special process flag to avoid recursive callbacks into
 * the filesystem during transactions.  We will also issue our own
 * warnings, so we explicitly skip any generic ones (silly of us).
 */
static inline gfp_t
kmem_flags_convert(unsigned int __nocast flags)
{
	gfp_t	lflags;

	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL));

	if (flags & KM_NOSLEEP) {
		lflags = GFP_ATOMIC | __GFP_NOWARN;
	} else {
		lflags = GFP_KERNEL | __GFP_NOWARN;
		if (PFLAGS_TEST_FSTRANS() || (flags & KM_NOFS))
			lflags &= ~__GFP_FS;
	}
	return lflags;
}

extern void *kmem_alloc(size_t, unsigned int __nocast);
extern void *kmem_realloc(void *, size_t, size_t, unsigned int __nocast);
extern void *kmem_zalloc(size_t, unsigned int __nocast);
extern void  kmem_free(void *, size_t);

/*
 * Zone interfaces
 */

#define KM_ZONE_HWALIGN	SLAB_HWCACHE_ALIGN
#define KM_ZONE_RECLAIM	SLAB_RECLAIM_ACCOUNT
#define KM_ZONE_SPREAD	0

#define kmem_zone	kmem_cache
#define kmem_zone_t	struct kmem_cache

static inline kmem_zone_t *
kmem_zone_init(int size, char *zone_name)
{
	return kmem_cache_create(zone_name, size, 0, 0, NULL, NULL);
}

static inline kmem_zone_t *
kmem_zone_init_flags(int size, char *zone_name, unsigned long flags,
		     void (*construct)(void *, kmem_zone_t *, unsigned long))
{
	return kmem_cache_create(zone_name, size, 0, flags, construct, NULL);
}

static inline void
kmem_zone_free(kmem_zone_t *zone, void *ptr)
{
	kmem_cache_free(zone, ptr);
}

static inline void
kmem_zone_destroy(kmem_zone_t *zone)
{
	if (zone && kmem_cache_destroy(zone))
		BUG();
}

extern void *kmem_zone_alloc(kmem_zone_t *, unsigned int __nocast);
extern void *kmem_zone_zalloc(kmem_zone_t *, unsigned int __nocast);

/*
 * Low memory cache shrinkers
 */

typedef struct shrinker *kmem_shaker_t;
typedef int (*kmem_shake_func_t)(int, gfp_t);

static inline kmem_shaker_t
kmem_shake_register(kmem_shake_func_t sfunc)
{
	return set_shrinker(DEFAULT_SEEKS, sfunc);
}

static inline void
kmem_shake_deregister(kmem_shaker_t shrinker)
{
	remove_shrinker(shrinker);
}

static inline int
kmem_shake_allow(gfp_t gfp_mask)
{
	return (gfp_mask & __GFP_WAIT);
}

#endif /* __XFS_SUPPORT_KMEM_H__ */
OpenPOWER on IntegriCloud