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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
/****************************************************************************
* arch/arm/src/armv7/arm_addrenv_kstack.c
*
* Copyright (C) 2014 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.
*
****************************************************************************/
/****************************************************************************
* Address Environment Interfaces
*
* Low-level interfaces used in binfmt/ to instantiate tasks with address
* environments. These interfaces all operate on type group_addrenv_t which
* is an abstract representation of a task group's address environment and
* must be defined in arch/arch.h if CONFIG_ARCH_ADDRENV is defined.
*
* up_addrenv_create - Create an address environment
* up_addrenv_destroy - Destroy an address environment.
* up_addrenv_vtext - Returns the virtual base address of the .text
* address environment
* up_addrenv_vdata - Returns the virtual base address of the .bss/.data
* address environment
* up_addrenv_heapsize - Returns the size of the initial heap allocation.
* up_addrenv_select - Instantiate an address environment
* up_addrenv_restore - Restore an address environment
* up_addrenv_clone - Copy an address environment from one location to
* another.
*
* Higher-level interfaces used by the tasking logic. These interfaces are
* used by the functions in sched/ and all operate on the thread which whose
* group been assigned an address environment by up_addrenv_clone().
*
* up_addrenv_attach - Clone the address environment assigned to one TCB
* to another. This operation is done when a pthread
* is created that share's the same group address
* environment.
* up_addrenv_detach - Release the thread's reference to an address
* environment when a task/thread exits.
*
* CONFIG_ARCH_STACK_DYNAMIC=y indicates that the user process stack resides
* in its own address space. This options is also *required* if
* CONFIG_BUILD_KERNEL and CONFIG_LIBC_EXECFUNCS are selected. Why?
* Because the caller's stack must be preserved in its own address space
* when we instantiate the environment of the new process in order to
* initialize it.
*
* NOTE: The naming of the CONFIG_ARCH_STACK_DYNAMIC selection implies that
* dynamic stack allocation is supported. Certainly this option must be set
* if dynamic stack allocation is supported by a platform. But the more
* general meaning of this configuration environment is simply that the
* stack has its own address space.
*
* If CONFIG_ARCH_STACK_DYNAMIC=y is selected then the platform specific
* code must export these additional interfaces:
*
* up_addrenv_ustackalloc - Create a stack address environment
* up_addrenv_ustackfree - Destroy a stack address environment.
* up_addrenv_vustack - Returns the virtual base address of the stack
* up_addrenv_ustackselect - Instantiate a stack address environment
*
* If CONFIG_ARCH_KERNEL_STACK is selected, then each user process will have
* two stacks: (1) a large (and possibly dynamic) user stack and (2) a
* smaller kernel stack. However, this option is *required* if both
* CONFIG_BUILD_KERNEL and CONFIG_LIBC_EXECFUNCS are selected. Why? Because
* when we instantiate and initialize the address environment of the new
* user process, we will temporarily lose the address environment of the old
* user process, including its stack contents. The kernel C logic will crash
* immediately with no valid stack in place.
*
* If CONFIG_ARCH_KERNEL_STACK=y is selected then the platform specific
* code must export these additional interfaces:
*
* up_addrenv_kstackalloc - Create a stack in the kernel address environment
* up_addrenv_kstackfree - Destroy the kernel stack.
* up_addrenv_vkstack - Return the base address of the kernel stack
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/sched.h>
#include <nuttx/kmalloc.h>
#include <nuttx/addrenv.h>
#include <nuttx/arch.h>
#include "addrenv.h"
#if defined(CONFIG_ARCH_ADDRENV) && defined(CONFIG_ARCH_KERNEL_STACK)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_addrenv_kstackalloc
*
* Description:
* This function is called when a new thread is created to allocate
* the new thread's kernel stack. This function may be called for certain
* terminating threads which have no kernel stack. It must be tolerant of
* that case.
*
* Input Parameters:
* tcb - The TCB of the thread that requires the kernel stack.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int up_addrenv_kstackalloc(FAR struct tcb_s *tcb)
{
bvdbg("tcb=%p stacksize=%u\n", tcb, ARCH_KERNEL_STACKSIZE);
DEBUGASSERT(tcb && tcb->xcp.kstack == 0);
/* Allocate the kernel stack */
tcb->xcp.kstack = (FAR uint32_t *)kmm_memalign(8, ARCH_KERNEL_STACKSIZE);
if (!tcb->xcp.kstack)
{
bdbg("ERROR: Failed to allocate the kernel stack\n");
return -ENOMEM;
}
return OK;
}
/****************************************************************************
* Name: up_addrenv_kstackfree
*
* Description:
* This function is called when any thread exits. This function frees
* the kernel stack.
*
* Input Parameters:
* tcb - The TCB of the thread that no longer requires the kernel stack.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int up_addrenv_kstackfree(FAR struct tcb_s *tcb)
{
bvdbg("tcb=%p\n", tcb);
DEBUGASSERT(tcb);
/* Does the exiting thread have a kernel stack? */
if (tcb->xcp.kstack)
{
/* Yes.. Free the kernel stack */
kmm_free(tcb->xcp.kstack);
tcb->xcp.kstack = NULL;
}
return OK;
}
#endif /* CONFIG_ARCH_ADDRENV && CONFIG_ARCH_KERNEL_STACK */
|
