source: mainline/kernel/generic/include/mm/as.h@ 8aaf9dc

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 8aaf9dc was 83b6ba9f, checked in by Jakub Jermar <jakub@…>, 11 years ago

Support for AS area backend shared data.

  • share_info_t is now created for every new address space area.
  • share_info_t was extended to point to AS area backend shared data.
  • AS area backend may decide to define create/destroy_shared_data() methods.
  • Anonymous backend_phys frames are now freed from phys_destroy_shared_data().
  • Fixed one case of forgotten locked mutex.
  • Property mode set to 100644
File size: 8.5 KB
Line 
1/*
2 * Copyright (c) 2010 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/** @addtogroup genericmm
30 * @{
31 */
32/** @file
33 */
34
35#ifndef KERN_AS_H_
36#define KERN_AS_H_
37
38#include <typedefs.h>
39#include <abi/mm/as.h>
40#include <arch/mm/page.h>
41#include <arch/mm/as.h>
42#include <arch/mm/asid.h>
43#include <arch/istate.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 <lib/elf.h>
50
51/**
52 * Defined to be true if user address space and kernel address space shadow each
53 * other.
54 *
55 */
56#define KERNEL_ADDRESS_SPACE_SHADOWED KERNEL_ADDRESS_SPACE_SHADOWED_ARCH
57
58#define KERNEL_ADDRESS_SPACE_START KERNEL_ADDRESS_SPACE_START_ARCH
59#define KERNEL_ADDRESS_SPACE_END KERNEL_ADDRESS_SPACE_END_ARCH
60#define USER_ADDRESS_SPACE_START USER_ADDRESS_SPACE_START_ARCH
61#define USER_ADDRESS_SPACE_END USER_ADDRESS_SPACE_END_ARCH
62
63/** Kernel address space. */
64#define FLAG_AS_KERNEL (1 << 0)
65
66/* Address space area attributes. */
67#define AS_AREA_ATTR_NONE 0
68#define AS_AREA_ATTR_PARTIAL 1 /**< Not fully initialized area. */
69
70/** The page fault was resolved by as_page_fault(). */
71#define AS_PF_OK 0
72
73/** The page fault was caused by memcpy_from_uspace() or memcpy_to_uspace(). */
74#define AS_PF_DEFER 1
75
76/** The page fault was not resolved by as_page_fault(). */
77#define AS_PF_FAULT 2
78
79/** The page fault was not resolved by as_page_fault(). Non-verbose version. */
80#define AS_PF_SILENT 3
81
82/** Address space structure.
83 *
84 * as_t contains the list of as_areas of userspace accessible
85 * pages for one or more tasks. Ranges of kernel memory pages are not
86 * supposed to figure in the list as they are shared by all tasks and
87 * set up during system initialization.
88 *
89 */
90typedef struct as {
91 /** Protected by asidlock. */
92 link_t inactive_as_with_asid_link;
93
94 /**
95 * Number of processors on which this
96 * address space is active. Protected by
97 * asidlock.
98 */
99 size_t cpu_refcount;
100
101 /** Address space identifier.
102 *
103 * Constant on architectures that do not
104 * support ASIDs. Protected by asidlock.
105 *
106 */
107 asid_t asid;
108
109 /** Number of references (i.e. tasks that reference this as). */
110 atomic_t refcount;
111
112 mutex_t lock;
113
114 /** B+tree of address space areas. */
115 btree_t as_area_btree;
116
117 /** Non-generic content. */
118 as_genarch_t genarch;
119
120 /** Architecture specific content. */
121 as_arch_t arch;
122} as_t;
123
124typedef struct {
125 pte_t *(* page_table_create)(unsigned int);
126 void (* page_table_destroy)(pte_t *);
127 void (* page_table_lock)(as_t *, bool);
128 void (* page_table_unlock)(as_t *, bool);
129 bool (* page_table_locked)(as_t *);
130} as_operations_t;
131
132/**
133 * This structure contains information associated with the shared address space
134 * area.
135 *
136 */
137typedef struct {
138 /** This lock must be acquired only when the as_area lock is held. */
139 mutex_t lock;
140 /** This structure can be deallocated if refcount drops to 0. */
141 size_t refcount;
142 /** True if the area has been ever shared. */
143 bool shared;
144
145 /**
146 * B+tree containing complete map of anonymous pages of the shared area.
147 */
148 btree_t pagemap;
149
150 /** Address space area backend. */
151 struct mem_backend *backend;
152 /** Address space area shared data. */
153 void *backend_shared_data;
154} share_info_t;
155
156/** Page fault access type. */
157typedef enum {
158 PF_ACCESS_READ,
159 PF_ACCESS_WRITE,
160 PF_ACCESS_EXEC,
161 PF_ACCESS_UNKNOWN
162} pf_access_t;
163
164struct mem_backend;
165
166/** Backend data stored in address space area. */
167typedef union mem_backend_data {
168 /** elf_backend members */
169 struct {
170 elf_header_t *elf;
171 elf_segment_header_t *segment;
172 };
173
174 /** phys_backend members */
175 struct {
176 uintptr_t base;
177 size_t frames;
178 bool anonymous;
179 };
180} mem_backend_data_t;
181
182/** Address space area structure.
183 *
184 * Each as_area_t structure describes one contiguous area of virtual memory.
185 *
186 */
187typedef struct {
188 mutex_t lock;
189
190 /** Containing address space. */
191 as_t *as;
192
193 /** Memory flags. */
194 unsigned int flags;
195
196 /** Address space area attributes. */
197 unsigned int attributes;
198
199 /** Number of pages in the area. */
200 size_t pages;
201
202 /** Number of resident pages in the area. */
203 size_t resident;
204
205 /** Base address of this area. */
206 uintptr_t base;
207
208 /** Map of used space. */
209 btree_t used_space;
210
211 /**
212 * If the address space area is shared. this is
213 * a reference to the share info structure.
214 */
215 share_info_t *sh_info;
216
217 /** Memory backend backing this address space area. */
218 struct mem_backend *backend;
219
220 /** Data to be used by the backend. */
221 mem_backend_data_t backend_data;
222} as_area_t;
223
224/** Address space area backend structure. */
225typedef struct mem_backend {
226 bool (* create)(as_area_t *);
227 bool (* resize)(as_area_t *, size_t);
228 void (* share)(as_area_t *);
229 void (* destroy)(as_area_t *);
230
231 bool (* is_resizable)(as_area_t *);
232 bool (* is_shareable)(as_area_t *);
233
234 int (* page_fault)(as_area_t *, uintptr_t, pf_access_t);
235 void (* frame_free)(as_area_t *, uintptr_t, uintptr_t);
236
237 bool (* create_shared_data)(as_area_t *);
238 void (* destroy_shared_data)(void *);
239} mem_backend_t;
240
241extern as_t *AS_KERNEL;
242
243extern as_operations_t *as_operations;
244extern list_t inactive_as_with_asid_list;
245
246extern void as_init(void);
247
248extern as_t *as_create(unsigned int);
249extern void as_destroy(as_t *);
250extern void as_hold(as_t *);
251extern void as_release(as_t *);
252extern void as_switch(as_t *, as_t *);
253extern int as_page_fault(uintptr_t, pf_access_t, istate_t *);
254
255extern as_area_t *as_area_create(as_t *, unsigned int, size_t, unsigned int,
256 mem_backend_t *, mem_backend_data_t *, uintptr_t *, uintptr_t);
257extern int as_area_destroy(as_t *, uintptr_t);
258extern int as_area_resize(as_t *, uintptr_t, size_t, unsigned int);
259extern int as_area_share(as_t *, uintptr_t, size_t, as_t *, unsigned int,
260 uintptr_t *, uintptr_t);
261extern int as_area_change_flags(as_t *, unsigned int, uintptr_t);
262
263extern unsigned int as_area_get_flags(as_area_t *);
264extern bool as_area_check_access(as_area_t *, pf_access_t);
265extern size_t as_area_get_size(uintptr_t);
266extern bool used_space_insert(as_area_t *, uintptr_t, size_t);
267extern bool used_space_remove(as_area_t *, uintptr_t, size_t);
268
269/* Interface to be implemented by architectures. */
270
271#ifndef as_constructor_arch
272extern int as_constructor_arch(as_t *, unsigned int);
273#endif /* !def as_constructor_arch */
274
275#ifndef as_destructor_arch
276extern int as_destructor_arch(as_t *);
277#endif /* !def as_destructor_arch */
278
279#ifndef as_create_arch
280extern int as_create_arch(as_t *, unsigned int);
281#endif /* !def as_create_arch */
282
283#ifndef as_install_arch
284extern void as_install_arch(as_t *);
285#endif /* !def as_install_arch */
286
287#ifndef as_deinstall_arch
288extern void as_deinstall_arch(as_t *);
289#endif /* !def as_deinstall_arch */
290
291/* Backend declarations and functions. */
292extern mem_backend_t anon_backend;
293extern mem_backend_t elf_backend;
294extern mem_backend_t phys_backend;
295
296/* Address space area related syscalls. */
297extern sysarg_t sys_as_area_create(uintptr_t, size_t, unsigned int, uintptr_t);
298extern sysarg_t sys_as_area_resize(uintptr_t, size_t, unsigned int);
299extern sysarg_t sys_as_area_change_flags(uintptr_t, unsigned int);
300extern sysarg_t sys_as_area_destroy(uintptr_t);
301
302/* Introspection functions. */
303extern void as_get_area_info(as_t *, as_area_info_t **, size_t *);
304extern void as_print(as_t *);
305
306#endif
307
308/** @}
309 */
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