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
|
/*
* Copyright (c) 2010, 2011, 2012, 2013 Richard Braun.
*
* 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, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will 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, see <http://www.gnu.org/licenses/>.
*
*
* Object caching and general purpose memory allocator.
*/
#ifndef _KERN_KMEM_H
#define _KERN_KMEM_H
#include <kern/stddef.h>
/*
* Object cache.
*/
struct kmem_cache;
/*
* Type for constructor functions.
*
* The pre-constructed state of an object is supposed to include only
* elements such as e.g. linked lists, locks, reference counters. Therefore
* constructors are expected to 1) never fail and 2) not need any
* user-provided data. The first constraint implies that object construction
* never performs dynamic resource allocation, which also means there is no
* need for destructors.
*/
typedef void (*kmem_cache_ctor_t)(void *);
/*
* Types for slab allocation/free functions.
*
* All addresses and sizes must be page-aligned.
*/
typedef unsigned long (*kmem_slab_alloc_fn_t)(size_t);
typedef void (*kmem_slab_free_fn_t)(unsigned long, size_t);
#include <kern/kmem_i.h>
/*
* Cache creation flags.
*/
#define KMEM_CACHE_NOCPUPOOL 0x1 /* Don't use the per-CPU pools */
#define KMEM_CACHE_NOOFFSLAB 0x2 /* Don't allocate external slab data */
#define KMEM_CACHE_VERIFY 0x4 /* Use debugging facilities */
/*
* Initialize a cache.
*
* If a slab allocation/free function pointer is NULL, the default backend
* (vm_kmem on the kernel map) is used for the allocation/free action.
*/
void kmem_cache_init(struct kmem_cache *cache, const char *name,
size_t obj_size, size_t align, kmem_cache_ctor_t ctor,
kmem_slab_alloc_fn_t slab_alloc_fn,
kmem_slab_free_fn_t slab_free_fn, int flags);
static inline size_t
kmem_cache_slab_size(struct kmem_cache *cache)
{
return cache->slab_size;
}
/*
* Allocate an object from a cache.
*/
void * kmem_cache_alloc(struct kmem_cache *cache);
/*
* Release an object to its cache.
*/
void kmem_cache_free(struct kmem_cache *cache, void *obj);
/*
* Display internal cache information.
*
* If cache is NULL, this function displays all managed caches.
*/
void kmem_cache_info(struct kmem_cache *cache);
/*
* Set up the kernel memory allocator module.
*
* This function should only be called by the VM system. Once it returns,
* caches can be initialized, but those using the default backend can only
* operate once the VM system is sufficiently ready.
*/
void kmem_setup(void);
/*
* Allocate size bytes of uninitialized memory.
*/
void * kmem_alloc(size_t size);
/*
* Allocate size bytes of zeroed memory.
*/
void * kmem_zalloc(size_t size);
/*
* Release memory obtained with kmem_alloc() or kmem_zalloc().
*
* The size argument must strictly match the value given at allocation time.
*/
void kmem_free(void *ptr, size_t size);
/*
* Display global kernel memory information.
*/
void kmem_info(void);
#endif /* _KERN_KMEM_H */
|
