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
|
/************************************************************************
* sched/kmm_semaphore.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************************/
/************************************************************************
* Included Files
************************************************************************/
#include <nuttx/config.h>
#include <nuttx/kmalloc.h>
#ifdef CONFIG_NUTTX_KERNEL
/* This logic is all tentatively and, hopefully, will grow in usability.
* For now, the kernel-mode build uses the memory manager that is
* provided in the user-space build. That is awkward but reasonable for
* the current level of support: At present, only memory protection is
* provided. Kernel-mode code may call into user-mode code, but not
* vice-versa. So hosting the memory manager in user-space allows the
* memory manager to be shared in both kernel- and user-mode spaces.
*
* In the longer run, if an MMU is support that can provide virtualized
* memory, then some SLAB memory manager will be required in kernel-space
* with some kind of brk() system call to obtain mapped heap space.
*
* In the current build model, the user-space module is built first. The
* file user_map.h is generated in the first pass and contains the
* addresses of the memory manager needed in this file:
*/
#include <arch/board/user_map.h>
/************************************************************************
* Pre-processor definition
************************************************************************/
/* These values are obtained from user_map.h */
#define KTRYSEMAPHORE() ((kmtrysemaphore_t) CONFIG_USER_MMTRYSEM )()
#define KGIVESEMAPHORE() ((kmgivesemaphore_t)CONFIG_USER_MMGIVESEM)()
/************************************************************************
* Private Types
************************************************************************/
typedef int (*kmtrysemaphore_t)(void);
typedef void (*kmgivesemaphore_t)(void);
/************************************************************************
* Private Functions
************************************************************************/
/************************************************************************
* Public Functions
************************************************************************/
/************************************************************************
* Name: kmm_trysemaphore
*
* Description:
* This is a simple redirection to the user-space mm_trysemaphore()
* function.
*
* Parameters:
* None
*
* Return Value:
* OK on success; a negated errno on failure
*
* Assumptions:
* 1. mm_trysemaphore() resides in user-space
* 2. The address of the user space mm_trysemaphore() is provided in
* user_map.h
* 3. The user-space mm_semaphore() is callable from kernel-space.
*
************************************************************************/
int kmm_trysemaphore(void)
{
return KTRYSEMAPHORE();
}
/************************************************************************
* Name: kmm_givesemaphore
*
* Description:
* This is a simple redirection to the user-space mm_givesemaphore()
* function.
*
* Parameters:
* None
*
* Return Value:
* OK on success; a negated errno on failure
*
* Assumptions:
* 1. mm_givesemaphore() resides in user-space
* 2. The address of the user space mm_givesemaphore() is provided in
* user_map.h
* 3. The user-space mm_semaphore() is callable from kernel-space.
*
************************************************************************/
void kmm_givesemaphore(void)
{
KGIVESEMAPHORE();
}
#endif /* CONFIG_NUTTX_KERNEL */
|
