source: mainline/generic/include/mm/as.h@ 482826d

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 482826d was 482826d, checked in by Jakub Jermar <jakub@…>, 19 years ago

Function for destroying address space for which there is no other reference in the kernel.
  • Property mode set to 100644
File size: 7.3 KB
Line 
1/*
2 * Copyright (C) 2001-2004 Jakub Jermar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
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
15 * derived from this software without specific prior written permission.
16 *
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
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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
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
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef __AS_H__
30#define __AS_H__
31
32/** Address space area flags. */
33#define AS_AREA_READ 1
34#define AS_AREA_WRITE 2
35#define AS_AREA_EXEC 4
36#define AS_AREA_CACHEABLE 8
37
38#ifdef KERNEL
39
40#include <arch/mm/page.h>
41#include <arch/mm/as.h>
42#include <arch/mm/asid.h>
43#include <arch/types.h>
44#include <typedefs.h>
45#include <synch/spinlock.h>
46#include <synch/mutex.h>
47#include <adt/list.h>
48#include <adt/btree.h>
49#include <elf.h>
50
51/** Defined to be true if user address space and kernel address space shadow each other. */
52#define KERNEL_ADDRESS_SPACE_SHADOWED KERNEL_ADDRESS_SPACE_SHADOWED_ARCH
53
54#define KERNEL_ADDRESS_SPACE_START KERNEL_ADDRESS_SPACE_START_ARCH
55#define KERNEL_ADDRESS_SPACE_END KERNEL_ADDRESS_SPACE_END_ARCH
56#define USER_ADDRESS_SPACE_START USER_ADDRESS_SPACE_START_ARCH
57#define USER_ADDRESS_SPACE_END USER_ADDRESS_SPACE_END_ARCH
58
59#define IS_KA(addr) ((addr)>=KERNEL_ADDRESS_SPACE_START && (addr)<=KERNEL_ADDRESS_SPACE_END)
60
61#define USTACK_ADDRESS USTACK_ADDRESS_ARCH
62
63#define FLAG_AS_KERNEL (1 << 0) /**< Kernel address space. */
64
65/** Address space structure.
66 *
67 * as_t contains the list of as_areas of userspace accessible
68 * pages for one or more tasks. Ranges of kernel memory pages are not
69 * supposed to figure in the list as they are shared by all tasks and
70 * set up during system initialization.
71 */
72struct as {
73 /** Protected by asidlock. */
74 link_t inactive_as_with_asid_link;
75
76 mutex_t lock;
77
78 /** Number of references (i.e tasks that reference this as). */
79 count_t refcount;
80
81 /** Number of processors on wich is this address space active. */
82 count_t cpu_refcount;
83
84 /** B+tree of address space areas. */
85 btree_t as_area_btree;
86
87 /** Page table pointer. Constant on architectures that use global page hash table. */
88 pte_t *page_table;
89
90 /** Address space identifier. Constant on architectures that do not support ASIDs.*/
91 asid_t asid;
92};
93
94struct as_operations {
95 pte_t *(* page_table_create)(int flags);
96 void (* page_table_destroy)(pte_t *page_table);
97 void (* page_table_lock)(as_t *as, bool lock);
98 void (* page_table_unlock)(as_t *as, bool unlock);
99};
100typedef struct as_operations as_operations_t;
101
102/** Address space area attributes. */
103#define AS_AREA_ATTR_NONE 0
104#define AS_AREA_ATTR_PARTIAL 1 /**< Not fully initialized area. */
105
106#define AS_PF_FAULT 0 /**< The page fault was not resolved by as_page_fault(). */
107#define AS_PF_OK 1 /**< The page fault was resolved by as_page_fault(). */
108#define AS_PF_DEFER 2 /**< The page fault was caused by memcpy_from_uspace()
109 or memcpy_to_uspace(). */
110
111/** This structure contains information associated with the shared address space area. */
112typedef struct {
113 mutex_t lock; /**< This lock must be acquired only when the as_area lock is held. */
114 count_t refcount; /**< This structure can be deallocated if refcount drops to 0. */
115 btree_t pagemap; /**< B+tree containing complete map of anonymous pages of the shared area. */
116} share_info_t;
117
118/** Address space area backend structure. */
119typedef struct {
120 int (* page_fault)(as_area_t *area, __address addr, pf_access_t access);
121 void (* frame_free)(as_area_t *area, __address page, __address frame);
122 void (* share)(as_area_t *area);
123} mem_backend_t;
124
125/** Backend data stored in address space area. */
126typedef union {
127 struct { /**< elf_backend members */
128 elf_header_t *elf;
129 elf_segment_header_t *segment;
130 };
131 struct { /**< phys_backend members */
132 __address base;
133 count_t frames;
134 };
135} mem_backend_data_t;
136
137/** Address space area structure.
138 *
139 * Each as_area_t structure describes one contiguous area of virtual memory.
140 * In the future, it should not be difficult to support shared areas.
141 */
142struct as_area {
143 mutex_t lock;
144 as_t *as; /**< Containing address space. */
145 int flags; /**< Flags related to the memory represented by the address space area. */
146 int attributes; /**< Attributes related to the address space area itself. */
147 count_t pages; /**< Size of this area in multiples of PAGE_SIZE. */
148 __address base; /**< Base address of this area. */
149 btree_t used_space; /**< Map of used space. */
150 share_info_t *sh_info; /**< If the address space area has been shared, this pointer will
151 reference the share info structure. */
152 mem_backend_t *backend; /**< Memory backend backing this address space area. */
153
154 /** Data to be used by the backend. */
155 mem_backend_data_t backend_data;
156};
157
158extern as_t *AS_KERNEL;
159extern as_operations_t *as_operations;
160
161extern spinlock_t inactive_as_with_asid_lock;
162extern link_t inactive_as_with_asid_head;
163
164extern void as_init(void);
165
166extern as_t *as_create(int flags);
167extern void as_destroy(as_t *as);
168extern void as_switch(as_t *old, as_t *new);
169extern int as_page_fault(__address page, pf_access_t access, istate_t *istate);
170
171extern as_area_t *as_area_create(as_t *as, int flags, size_t size, __address base, int attrs,
172 mem_backend_t *backend, mem_backend_data_t *backend_data);
173extern int as_area_destroy(as_t *as, __address address);
174extern int as_area_resize(as_t *as, __address address, size_t size, int flags);
175int as_area_share(as_t *src_as, __address src_base, size_t acc_size,
176 as_t *dst_as, __address dst_base, int dst_flags_mask);
177
178extern int as_area_get_flags(as_area_t *area);
179extern bool as_area_check_access(as_area_t *area, pf_access_t access);
180extern size_t as_get_size(__address base);
181extern int used_space_insert(as_area_t *a, __address page, count_t count);
182extern int used_space_remove(as_area_t *a, __address page, count_t count);
183
184/* Interface to be implemented by architectures. */
185#ifndef as_install_arch
186extern void as_install_arch(as_t *as);
187#endif /* !def as_install_arch */
188
189/* Backend declarations. */
190extern mem_backend_t anon_backend;
191extern mem_backend_t elf_backend;
192extern mem_backend_t phys_backend;
193
194/* Address space area related syscalls. */
195extern __native sys_as_area_create(__address address, size_t size, int flags);
196extern __native sys_as_area_resize(__address address, size_t size, int flags);
197extern __native sys_as_area_destroy(__address address);
198
199#endif /* KERNEL */
200
201#endif
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