source: mainline/kernel/generic/include/mm/as.h@ 78de83de

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 78de83de was 78de83de, checked in by Jiří Zárevúcky <jiri.zarevucky@…>, 7 years ago

Improve kernel spinlock and AS refcount.
  • Property mode set to 100644
File size: 8.7 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 <synch/spinlock.h>
45#include <synch/mutex.h>
46#include <adt/list.h>
47#include <adt/btree.h>
48#include <lib/elf.h>
49#include <arch.h>
50#include <lib/refcount.h>
51
52#define AS THE->as
53
54
55/**
56 * Defined to be true if user address space and kernel address space shadow each
57 * other.
58 *
59 */
60#define KERNEL_ADDRESS_SPACE_SHADOWED KERNEL_ADDRESS_SPACE_SHADOWED_ARCH
61
62#define KERNEL_ADDRESS_SPACE_START KERNEL_ADDRESS_SPACE_START_ARCH
63#define KERNEL_ADDRESS_SPACE_END KERNEL_ADDRESS_SPACE_END_ARCH
64#define USER_ADDRESS_SPACE_START USER_ADDRESS_SPACE_START_ARCH
65#define USER_ADDRESS_SPACE_END USER_ADDRESS_SPACE_END_ARCH
66
67/** Kernel address space. */
68#define FLAG_AS_KERNEL (1 << 0)
69
70/* Address space area attributes. */
71#define AS_AREA_ATTR_NONE 0
72#define AS_AREA_ATTR_PARTIAL 1 /**< Not fully initialized area. */
73
74/** The page fault was resolved by as_page_fault(). */
75#define AS_PF_OK 0
76
77/** The page fault was caused by memcpy_from_uspace() or memcpy_to_uspace(). */
78#define AS_PF_DEFER 1
79
80/** The page fault was not resolved by as_page_fault(). */
81#define AS_PF_FAULT 2
82
83/** The page fault was not resolved by as_page_fault(). Non-verbose version. */
84#define AS_PF_SILENT 3
85
86/** Address space structure.
87 *
88 * as_t contains the list of as_areas of userspace accessible
89 * pages for one or more tasks. Ranges of kernel memory pages are not
90 * supposed to figure in the list as they are shared by all tasks and
91 * set up during system initialization.
92 *
93 */
94typedef struct as {
95 /** Protected by asidlock. */
96 link_t inactive_as_with_asid_link;
97
98 /**
99 * Number of processors on which this
100 * address space is active. Protected by
101 * asidlock.
102 */
103 size_t cpu_refcount;
104
105 /** Address space identifier.
106 *
107 * Constant on architectures that do not
108 * support ASIDs. Protected by asidlock.
109 *
110 */
111 asid_t asid;
112
113 /** Number of references (i.e. tasks that reference this as). */
114 atomic_refcount_t refcount;
115
116 mutex_t lock;
117
118 /** B+tree of address space areas. */
119 btree_t as_area_btree;
120
121 /** Non-generic content. */
122 as_genarch_t genarch;
123
124 /** Architecture specific content. */
125 as_arch_t arch;
126} as_t;
127
128typedef struct {
129 pte_t *(*page_table_create)(unsigned int);
130 void (*page_table_destroy)(pte_t *);
131 void (*page_table_lock)(as_t *, bool);
132 void (*page_table_unlock)(as_t *, bool);
133 bool (*page_table_locked)(as_t *);
134} as_operations_t;
135
136/**
137 * This structure contains information associated with the shared address space
138 * area.
139 *
140 */
141typedef struct {
142 /** This lock must be acquired only when the as_area lock is held. */
143 mutex_t lock;
144 /** This structure can be deallocated if refcount drops to 0. */
145 size_t refcount;
146 /** True if the area has been ever shared. */
147 bool shared;
148
149 /**
150 * B+tree containing complete map of anonymous pages of the shared area.
151 */
152 btree_t pagemap;
153
154 /** Address space area backend. */
155 struct mem_backend *backend;
156 /** Address space area shared data. */
157 void *backend_shared_data;
158} share_info_t;
159
160/** Page fault access type. */
161typedef enum {
162 PF_ACCESS_READ,
163 PF_ACCESS_WRITE,
164 PF_ACCESS_EXEC,
165 PF_ACCESS_UNKNOWN
166} pf_access_t;
167
168struct mem_backend;
169
170/** Backend data stored in address space area. */
171typedef union mem_backend_data {
172 /* anon_backend members */
173 struct {
174 };
175
176 /** elf_backend members */
177 struct {
178 elf_header_t *elf;
179 elf_segment_header_t *segment;
180 };
181
182 /** phys_backend members */
183 struct {
184 uintptr_t base;
185 size_t frames;
186 bool anonymous;
187 };
188
189 /** user_backend members */
190 struct {
191 as_area_pager_info_t pager_info;
192 };
193
194} mem_backend_data_t;
195
196/** Address space area structure.
197 *
198 * Each as_area_t structure describes one contiguous area of virtual memory.
199 *
200 */
201typedef struct {
202 mutex_t lock;
203
204 /** Containing address space. */
205 as_t *as;
206
207 /** Memory flags. */
208 unsigned int flags;
209
210 /** Address space area attributes. */
211 unsigned int attributes;
212
213 /** Number of pages in the area. */
214 size_t pages;
215
216 /** Number of resident pages in the area. */
217 size_t resident;
218
219 /** Base address of this area. */
220 uintptr_t base;
221
222 /** Map of used space. */
223 btree_t used_space;
224
225 /**
226 * If the address space area is shared. this is
227 * a reference to the share info structure.
228 */
229 share_info_t *sh_info;
230
231 /** Memory backend backing this address space area. */
232 struct mem_backend *backend;
233
234 /** Data to be used by the backend. */
235 mem_backend_data_t backend_data;
236} as_area_t;
237
238/** Address space area backend structure. */
239typedef struct mem_backend {
240 bool (*create)(as_area_t *);
241 bool (*resize)(as_area_t *, size_t);
242 void (*share)(as_area_t *);
243 void (*destroy)(as_area_t *);
244
245 bool (*is_resizable)(as_area_t *);
246 bool (*is_shareable)(as_area_t *);
247
248 int (*page_fault)(as_area_t *, uintptr_t, pf_access_t);
249 void (*frame_free)(as_area_t *, uintptr_t, uintptr_t);
250
251 bool (*create_shared_data)(as_area_t *);
252 void (*destroy_shared_data)(void *);
253} mem_backend_t;
254
255extern as_t *AS_KERNEL;
256
257extern as_operations_t *as_operations;
258extern list_t inactive_as_with_asid_list;
259
260extern void as_init(void);
261
262extern as_t *as_create(unsigned int);
263extern void as_destroy(as_t *);
264extern void as_hold(as_t *);
265extern void as_release(as_t *);
266extern void as_switch(as_t *, as_t *);
267extern int as_page_fault(uintptr_t, pf_access_t, istate_t *);
268
269extern as_area_t *as_area_create(as_t *, unsigned int, size_t, unsigned int,
270 mem_backend_t *, mem_backend_data_t *, uintptr_t *, uintptr_t);
271extern errno_t as_area_destroy(as_t *, uintptr_t);
272extern errno_t as_area_resize(as_t *, uintptr_t, size_t, unsigned int);
273extern errno_t as_area_share(as_t *, uintptr_t, size_t, as_t *, unsigned int,
274 uintptr_t *, uintptr_t);
275extern errno_t as_area_change_flags(as_t *, unsigned int, uintptr_t);
276
277extern unsigned int as_area_get_flags(as_area_t *);
278extern bool as_area_check_access(as_area_t *, pf_access_t);
279extern size_t as_area_get_size(uintptr_t);
280extern bool used_space_insert(as_area_t *, uintptr_t, size_t);
281extern bool used_space_remove(as_area_t *, uintptr_t, size_t);
282
283/* Interface to be implemented by architectures. */
284
285#ifndef as_constructor_arch
286extern errno_t as_constructor_arch(as_t *, unsigned int);
287#endif /* !def as_constructor_arch */
288
289#ifndef as_destructor_arch
290extern int as_destructor_arch(as_t *);
291#endif /* !def as_destructor_arch */
292
293#ifndef as_create_arch
294extern errno_t as_create_arch(as_t *, unsigned int);
295#endif /* !def as_create_arch */
296
297#ifndef as_install_arch
298extern void as_install_arch(as_t *);
299#endif /* !def as_install_arch */
300
301#ifndef as_deinstall_arch
302extern void as_deinstall_arch(as_t *);
303#endif /* !def as_deinstall_arch */
304
305/* Backend declarations and functions. */
306extern mem_backend_t anon_backend;
307extern mem_backend_t elf_backend;
308extern mem_backend_t phys_backend;
309extern mem_backend_t user_backend;
310
311/* Address space area related syscalls. */
312extern sysarg_t sys_as_area_create(uintptr_t, size_t, unsigned int, uintptr_t,
313 as_area_pager_info_t *);
314extern sys_errno_t sys_as_area_resize(uintptr_t, size_t, unsigned int);
315extern sys_errno_t sys_as_area_change_flags(uintptr_t, unsigned int);
316extern sys_errno_t sys_as_area_destroy(uintptr_t);
317
318/* Introspection functions. */
319extern void as_get_area_info(as_t *, as_area_info_t **, size_t *);
320extern void as_print(as_t *);
321
322#endif
323
324/** @}
325 */
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