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/*
1
/*
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 * Copyright (c) 2001-2004 Jakub Jermar
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 * Copyright (c) 2001-2004 Jakub Jermar
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 * All rights reserved.
3
 * All rights reserved.
4
 *
4
 *
5
 * Redistribution and use in source and binary forms, with or without
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
6
 * modification, are permitted provided that the following conditions
7
 * are met:
7
 * are met:
8
 *
8
 *
9
 * - Redistributions of source code must retain the above copyright
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
15
 *   derived from this software without specific prior written permission.
16
 *
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
27
 */
28
 
28
 
29
/** @addtogroup genericmm
29
/** @addtogroup genericmm
30
 * @{
30
 * @{
31
 */
31
 */
32
/** @file
32
/** @file
33
 */
33
 */
34
 
34
 
35
#ifndef KERN_AS_H_
35
#ifndef KERN_AS_H_
36
#define KERN_AS_H_
36
#define KERN_AS_H_
37
 
37
 
38
/** Address space area flags. */
38
/** Address space area flags. */
39
#define AS_AREA_READ        1
39
#define AS_AREA_READ        1
40
#define AS_AREA_WRITE       2
40
#define AS_AREA_WRITE       2
41
#define AS_AREA_EXEC        4
41
#define AS_AREA_EXEC        4
42
#define AS_AREA_CACHEABLE   8
42
#define AS_AREA_CACHEABLE   8
43
 
43
 
44
#ifdef KERNEL
44
#ifdef KERNEL
45
 
45
 
46
#include <arch/mm/page.h>
46
#include <arch/mm/page.h>
47
#include <arch/mm/as.h>
47
#include <arch/mm/as.h>
48
#include <arch/mm/asid.h>
48
#include <arch/mm/asid.h>
49
#include <arch/types.h>
49
#include <arch/types.h>
50
#include <synch/spinlock.h>
50
#include <synch/spinlock.h>
51
#include <synch/mutex.h>
51
#include <synch/mutex.h>
52
#include <adt/list.h>
52
#include <adt/list.h>
53
#include <adt/btree.h>
53
#include <adt/btree.h>
54
#include <lib/elf.h>
54
#include <lib/elf.h>
55
 
55
 
56
#ifdef __OBJC__
56
#ifdef __OBJC__
57
#include <lib/objc.h>
57
#include <lib/objc.h>
58
#endif
58
#endif
59
 
59
 
60
/**
60
/**
61
 * Defined to be true if user address space and kernel address space shadow each
61
 * Defined to be true if user address space and kernel address space shadow each
62
 * other.
62
 * other.
63
 */
63
 */
64
#define KERNEL_ADDRESS_SPACE_SHADOWED   KERNEL_ADDRESS_SPACE_SHADOWED_ARCH
64
#define KERNEL_ADDRESS_SPACE_SHADOWED   KERNEL_ADDRESS_SPACE_SHADOWED_ARCH
65
 
65
 
66
#define KERNEL_ADDRESS_SPACE_START  KERNEL_ADDRESS_SPACE_START_ARCH
66
#define KERNEL_ADDRESS_SPACE_START  KERNEL_ADDRESS_SPACE_START_ARCH
67
#define KERNEL_ADDRESS_SPACE_END    KERNEL_ADDRESS_SPACE_END_ARCH
67
#define KERNEL_ADDRESS_SPACE_END    KERNEL_ADDRESS_SPACE_END_ARCH
68
#define USER_ADDRESS_SPACE_START    USER_ADDRESS_SPACE_START_ARCH
68
#define USER_ADDRESS_SPACE_START    USER_ADDRESS_SPACE_START_ARCH
69
#define USER_ADDRESS_SPACE_END      USER_ADDRESS_SPACE_END_ARCH
69
#define USER_ADDRESS_SPACE_END      USER_ADDRESS_SPACE_END_ARCH
70
 
70
 
71
#define USTACK_ADDRESS          USTACK_ADDRESS_ARCH
71
#define USTACK_ADDRESS          USTACK_ADDRESS_ARCH
72
 
72
 
73
/** Kernel address space. */
73
/** Kernel address space. */
74
#define FLAG_AS_KERNEL          (1 << 0)    
74
#define FLAG_AS_KERNEL          (1 << 0)    
75
 
75
 
76
/* Address space area attributes. */
76
/* Address space area attributes. */
77
#define AS_AREA_ATTR_NONE   0
77
#define AS_AREA_ATTR_NONE   0
78
#define AS_AREA_ATTR_PARTIAL    1   /**< Not fully initialized area. */
78
#define AS_AREA_ATTR_PARTIAL    1   /**< Not fully initialized area. */
79
 
79
 
80
/** The page fault was not resolved by as_page_fault(). */
80
/** The page fault was not resolved by as_page_fault(). */
81
#define AS_PF_FAULT     0
81
#define AS_PF_FAULT     0
82
/** The page fault was resolved by as_page_fault(). */
82
/** The page fault was resolved by as_page_fault(). */
83
#define AS_PF_OK        1
83
#define AS_PF_OK        1
84
/** The page fault was caused by memcpy_from_uspace() or memcpy_to_uspace(). */
84
/** The page fault was caused by memcpy_from_uspace() or memcpy_to_uspace(). */
85
#define AS_PF_DEFER     2
85
#define AS_PF_DEFER     2
86
 
86
 
87
#ifdef __OBJC__
87
#ifdef __OBJC__
88
@interface as_t : base_t {
88
@interface as_t : base_t {
89
    @public
89
    @public
90
        /** Protected by asidlock. */
90
        /** Protected by asidlock. */
91
        link_t inactive_as_with_asid_link;
91
        link_t inactive_as_with_asid_link;
-
 
92
        /**
-
 
93
         * Number of processors on wich is this address space active.
-
 
94
         * Protected by asidlock.
-
 
95
         */
-
 
96
        count_t cpu_refcount;
-
 
97
        /**
-
 
98
         * Address space identifier.
-
 
99
         * Constant on architectures that do not support ASIDs.
-
 
100
         * Protected by asidlock.  
-
 
101
         */
-
 
102
        asid_t asid;
92
       
103
       
93
        mutex_t lock;
104
        mutex_t lock;
94
       
105
       
95
        /** Number of references (i.e tasks that reference this as). */
106
        /** Number of references (i.e tasks that reference this as). */
96
        count_t refcount;
107
        count_t refcount;
97
       
108
       
98
        /** Number of processors on wich is this address space active. */
-
 
99
        count_t cpu_refcount;
-
 
100
       
-
 
101
        /** B+tree of address space areas. */
109
        /** B+tree of address space areas. */
102
        btree_t as_area_btree;
110
        btree_t as_area_btree;
103
       
111
       
104
        /**
-
 
105
         *  Address space identifier.
-
 
106
         *  Constant on architectures that do not support ASIDs.
-
 
107
         */
-
 
108
        asid_t asid;
-
 
109
       
-
 
110
        /** Non-generic content. */
112
        /** Non-generic content. */
111
        as_genarch_t genarch;
113
        as_genarch_t genarch;
112
       
114
       
113
        /** Architecture specific content. */
115
        /** Architecture specific content. */
114
        as_arch_t arch;
116
        as_arch_t arch;
115
}
117
}
116
 
118
 
117
+ (pte_t *) page_table_create: (int) flags;
119
+ (pte_t *) page_table_create: (int) flags;
118
+ (void) page_table_destroy: (pte_t *) page_table;
120
+ (void) page_table_destroy: (pte_t *) page_table;
119
- (void) page_table_lock: (bool) _lock;
121
- (void) page_table_lock: (bool) _lock;
120
- (void) page_table_unlock: (bool) unlock;
122
- (void) page_table_unlock: (bool) unlock;
121
 
123
 
122
@end
124
@end
123
 
125
 
124
#else
126
#else
125
 
127
 
126
/** Address space structure.
128
/** Address space structure.
127
 *
129
 *
128
 * as_t contains the list of as_areas of userspace accessible
130
 * as_t contains the list of as_areas of userspace accessible
129
 * pages for one or more tasks. Ranges of kernel memory pages are not
131
 * pages for one or more tasks. Ranges of kernel memory pages are not
130
 * supposed to figure in the list as they are shared by all tasks and
132
 * supposed to figure in the list as they are shared by all tasks and
131
 * set up during system initialization.
133
 * set up during system initialization.
132
 */
134
 */
133
typedef struct as {
135
typedef struct as {
134
    /** Protected by asidlock. */
136
    /** Protected by asidlock. */
135
    link_t inactive_as_with_asid_link;
137
    link_t inactive_as_with_asid_link;
-
 
138
    /**
-
 
139
     * Number of processors on wich is this address space active.
-
 
140
     * Protected by asidlock.
-
 
141
     */
-
 
142
    count_t cpu_refcount;
-
 
143
    /**
-
 
144
     * Address space identifier.
-
 
145
     * Constant on architectures that do not support ASIDs.
-
 
146
     * Protected by asidlock.
-
 
147
     */
-
 
148
    asid_t asid;
136
 
149
 
137
    mutex_t lock;
150
    mutex_t lock;
138
 
151
 
139
    /** Number of references (i.e tasks that reference this as). */
152
    /** Number of references (i.e tasks that reference this as). */
140
    count_t refcount;
153
    count_t refcount;
141
 
154
 
142
    /** Number of processors on wich is this address space active. */
-
 
143
    count_t cpu_refcount;
-
 
144
 
-
 
145
    /** B+tree of address space areas. */
155
    /** B+tree of address space areas. */
146
    btree_t as_area_btree;
156
    btree_t as_area_btree;
147
   
157
   
148
    /**
-
 
149
     *  Address space identifier.
-
 
150
     *  Constant on architectures that do not support ASIDs.
-
 
151
     */
-
 
152
    asid_t asid;
-
 
153
   
-
 
154
    /** Non-generic content. */
158
    /** Non-generic content. */
155
    as_genarch_t genarch;
159
    as_genarch_t genarch;
156
 
160
 
157
    /** Architecture specific content. */
161
    /** Architecture specific content. */
158
    as_arch_t arch;
162
    as_arch_t arch;
159
} as_t;
163
} as_t;
160
 
164
 
161
typedef struct {
165
typedef struct {
162
    pte_t *(* page_table_create)(int flags);
166
    pte_t *(* page_table_create)(int flags);
163
    void (* page_table_destroy)(pte_t *page_table);
167
    void (* page_table_destroy)(pte_t *page_table);
164
    void (* page_table_lock)(as_t *as, bool lock);
168
    void (* page_table_lock)(as_t *as, bool lock);
165
    void (* page_table_unlock)(as_t *as, bool unlock);
169
    void (* page_table_unlock)(as_t *as, bool unlock);
166
} as_operations_t;
170
} as_operations_t;
167
#endif
171
#endif
168
 
172
 
169
/**
173
/**
170
 * This structure contains information associated with the shared address space
174
 * This structure contains information associated with the shared address space
171
 * area.
175
 * area.
172
 */
176
 */
173
typedef struct {
177
typedef struct {
174
    /** This lock must be acquired only when the as_area lock is held. */
178
    /** This lock must be acquired only when the as_area lock is held. */
175
    mutex_t lock;      
179
    mutex_t lock;      
176
    /** This structure can be deallocated if refcount drops to 0. */
180
    /** This structure can be deallocated if refcount drops to 0. */
177
    count_t refcount;
181
    count_t refcount;
178
    /**
182
    /**
179
     * B+tree containing complete map of anonymous pages of the shared area.
183
     * B+tree containing complete map of anonymous pages of the shared area.
180
     */
184
     */
181
    btree_t pagemap;
185
    btree_t pagemap;
182
} share_info_t;
186
} share_info_t;
183
 
187
 
184
/** Page fault access type. */
188
/** Page fault access type. */
185
typedef enum {
189
typedef enum {
186
    PF_ACCESS_READ,
190
    PF_ACCESS_READ,
187
    PF_ACCESS_WRITE,
191
    PF_ACCESS_WRITE,
188
    PF_ACCESS_EXEC
192
    PF_ACCESS_EXEC
189
} pf_access_t;
193
} pf_access_t;
190
 
194
 
191
struct mem_backend;
195
struct mem_backend;
192
 
196
 
193
/** Backend data stored in address space area. */
197
/** Backend data stored in address space area. */
194
typedef union mem_backend_data {
198
typedef union mem_backend_data {
195
    struct {    /**< elf_backend members */
199
    struct {    /**< elf_backend members */
196
        elf_header_t *elf;
200
        elf_header_t *elf;
197
        elf_segment_header_t *segment;
201
        elf_segment_header_t *segment;
198
    };
202
    };
199
    struct {    /**< phys_backend members */
203
    struct {    /**< phys_backend members */
200
        uintptr_t base;
204
        uintptr_t base;
201
        count_t frames;
205
        count_t frames;
202
    };
206
    };
203
} mem_backend_data_t;
207
} mem_backend_data_t;
204
 
208
 
205
/** Address space area structure.
209
/** Address space area structure.
206
 *
210
 *
207
 * Each as_area_t structure describes one contiguous area of virtual memory.
211
 * Each as_area_t structure describes one contiguous area of virtual memory.
208
 * In the future, it should not be difficult to support shared areas.
-
 
209
 */
212
 */
210
typedef struct {
213
typedef struct {
211
    mutex_t lock;
214
    mutex_t lock;
212
    /** Containing address space. */
215
    /** Containing address space. */
213
    as_t *as;      
216
    as_t *as;      
214
    /**
217
    /**
215
     * Flags related to the memory represented by the address space area.
218
     * Flags related to the memory represented by the address space area.
216
     */
219
     */
217
    int flags;
220
    int flags;
218
    /** Attributes related to the address space area itself. */
221
    /** Attributes related to the address space area itself. */
219
    int attributes;
222
    int attributes;
220
    /** Size of this area in multiples of PAGE_SIZE. */
223
    /** Size of this area in multiples of PAGE_SIZE. */
221
    count_t pages;
224
    count_t pages;
222
    /** Base address of this area. */
225
    /** Base address of this area. */
223
    uintptr_t base;
226
    uintptr_t base;
224
    /** Map of used space. */
227
    /** Map of used space. */
225
    btree_t used_space;
228
    btree_t used_space;
226
 
229
 
227
    /**
230
    /**
228
     * If the address space area has been shared, this pointer will
231
     * If the address space area has been shared, this pointer will
229
     * reference the share info structure.
232
     * reference the share info structure.
230
     */
233
     */
231
    share_info_t *sh_info;
234
    share_info_t *sh_info;
232
 
235
 
233
    /** Memory backend backing this address space area. */
236
    /** Memory backend backing this address space area. */
234
    struct mem_backend *backend;
237
    struct mem_backend *backend;
235
 
238
 
236
    /** Data to be used by the backend. */
239
    /** Data to be used by the backend. */
237
    mem_backend_data_t backend_data;
240
    mem_backend_data_t backend_data;
238
} as_area_t;
241
} as_area_t;
239
 
242
 
240
/** Address space area backend structure. */
243
/** Address space area backend structure. */
241
typedef struct mem_backend {
244
typedef struct mem_backend {
242
    int (* page_fault)(as_area_t *area, uintptr_t addr, pf_access_t access);
245
    int (* page_fault)(as_area_t *area, uintptr_t addr, pf_access_t access);
243
    void (* frame_free)(as_area_t *area, uintptr_t page, uintptr_t frame);
246
    void (* frame_free)(as_area_t *area, uintptr_t page, uintptr_t frame);
244
    void (* share)(as_area_t *area);
247
    void (* share)(as_area_t *area);
245
} mem_backend_t;
248
} mem_backend_t;
246
 
249
 
247
extern as_t *AS_KERNEL;
250
extern as_t *AS_KERNEL;
248
 
251
 
249
#ifndef __OBJC__
252
#ifndef __OBJC__
250
extern as_operations_t *as_operations;
253
extern as_operations_t *as_operations;
251
#endif
254
#endif
252
 
255
 
253
SPINLOCK_EXTERN(inactive_as_with_asid_lock);
-
 
254
extern link_t inactive_as_with_asid_head;
256
extern link_t inactive_as_with_asid_head;
255
 
257
 
256
extern void as_init(void);
258
extern void as_init(void);
257
 
259
 
258
extern as_t *as_create(int flags);
260
extern as_t *as_create(int flags);
259
extern void as_destroy(as_t *as);
261
extern void as_destroy(as_t *as);
260
extern void as_switch(as_t *old_as, as_t *new_as);
262
extern void as_switch(as_t *old_as, as_t *new_as);
261
extern int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate);
263
extern int as_page_fault(uintptr_t page, pf_access_t access, istate_t *istate);
262
 
264
 
263
extern as_area_t *as_area_create(as_t *as, int flags, size_t size,
265
extern as_area_t *as_area_create(as_t *as, int flags, size_t size,
264
    uintptr_t base, int attrs, mem_backend_t *backend,
266
    uintptr_t base, int attrs, mem_backend_t *backend,
265
    mem_backend_data_t *backend_data);
267
    mem_backend_data_t *backend_data);
266
extern int as_area_destroy(as_t *as, uintptr_t address);   
268
extern int as_area_destroy(as_t *as, uintptr_t address);   
267
extern int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags);
269
extern int as_area_resize(as_t *as, uintptr_t address, size_t size, int flags);
268
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
270
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
269
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask);
271
    as_t *dst_as, uintptr_t dst_base, int dst_flags_mask);
270
 
272
 
271
extern int as_area_get_flags(as_area_t *area);
273
extern int as_area_get_flags(as_area_t *area);
272
extern bool as_area_check_access(as_area_t *area, pf_access_t access);
274
extern bool as_area_check_access(as_area_t *area, pf_access_t access);
273
extern size_t as_get_size(uintptr_t base);
275
extern size_t as_get_size(uintptr_t base);
274
extern int used_space_insert(as_area_t *a, uintptr_t page, count_t count);
276
extern int used_space_insert(as_area_t *a, uintptr_t page, count_t count);
275
extern int used_space_remove(as_area_t *a, uintptr_t page, count_t count);
277
extern int used_space_remove(as_area_t *a, uintptr_t page, count_t count);
276
 
278
 
277
 
279
 
278
/* Interface to be implemented by architectures. */
280
/* Interface to be implemented by architectures. */
279
#ifndef as_constructor_arch
281
#ifndef as_constructor_arch
280
extern int as_constructor_arch(as_t *as, int flags);
282
extern int as_constructor_arch(as_t *as, int flags);
281
#endif /* !def as_constructor_arch */
283
#endif /* !def as_constructor_arch */
282
#ifndef as_destructor_arch
284
#ifndef as_destructor_arch
283
extern int as_destructor_arch(as_t *as);
285
extern int as_destructor_arch(as_t *as);
284
#endif /* !def as_destructor_arch */
286
#endif /* !def as_destructor_arch */
285
#ifndef as_create_arch
287
#ifndef as_create_arch
286
extern int as_create_arch(as_t *as, int flags);
288
extern int as_create_arch(as_t *as, int flags);
287
#endif /* !def as_create_arch */
289
#endif /* !def as_create_arch */
288
#ifndef as_install_arch
290
#ifndef as_install_arch
289
extern void as_install_arch(as_t *as);
291
extern void as_install_arch(as_t *as);
290
#endif /* !def as_install_arch */
292
#endif /* !def as_install_arch */
291
#ifndef as_deinstall_arch
293
#ifndef as_deinstall_arch
292
extern void as_deinstall_arch(as_t *as);
294
extern void as_deinstall_arch(as_t *as);
293
#endif /* !def as_deinstall_arch */
295
#endif /* !def as_deinstall_arch */
294
 
296
 
295
/* Backend declarations and functions. */
297
/* Backend declarations and functions. */
296
extern mem_backend_t anon_backend;
298
extern mem_backend_t anon_backend;
297
extern mem_backend_t elf_backend;
299
extern mem_backend_t elf_backend;
298
extern mem_backend_t phys_backend;
300
extern mem_backend_t phys_backend;
299
 
301
 
300
extern int elf_load(elf_header_t *header, as_t *as);
302
extern int elf_load(elf_header_t *header, as_t *as);
301
 
303
 
302
/* Address space area related syscalls. */
304
/* Address space area related syscalls. */
303
extern unative_t sys_as_area_create(uintptr_t address, size_t size, int flags);
305
extern unative_t sys_as_area_create(uintptr_t address, size_t size, int flags);
304
extern unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags);
306
extern unative_t sys_as_area_resize(uintptr_t address, size_t size, int flags);
305
extern unative_t sys_as_area_destroy(uintptr_t address);
307
extern unative_t sys_as_area_destroy(uintptr_t address);
306
 
308
 
307
/* Introspection functions. */
309
/* Introspection functions. */
308
extern void as_print(as_t *as);
310
extern void as_print(as_t *as);
309
 
311
 
310
#endif /* KERNEL */
312
#endif /* KERNEL */
311
 
313
 
312
#endif
314
#endif
313
 
315
 
314
/** @}
316
/** @}
315
 */
317
 */
316
 
318