2 * Copyright (C) 2001-2004 Jakub Jermar
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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.
29 /** @addtogroup genericmm
38 /** Address space area flags. */
39 #define AS_AREA_READ 1
40 #define AS_AREA_WRITE 2
41 #define AS_AREA_EXEC 4
42 #define AS_AREA_CACHEABLE 8
46 #include <arch/mm/page.h>
47 #include <arch/mm/as.h>
48 #include <arch/mm/asid.h>
49 #include <arch/types.h>
51 #include <synch/spinlock.h>
52 #include <synch/mutex.h>
54 #include <adt/btree.h>
57 /** Defined to be true if user address space and kernel address space shadow each other. */
58 #define KERNEL_ADDRESS_SPACE_SHADOWED KERNEL_ADDRESS_SPACE_SHADOWED_ARCH
60 #define KERNEL_ADDRESS_SPACE_START KERNEL_ADDRESS_SPACE_START_ARCH
61 #define KERNEL_ADDRESS_SPACE_END KERNEL_ADDRESS_SPACE_END_ARCH
62 #define USER_ADDRESS_SPACE_START USER_ADDRESS_SPACE_START_ARCH
63 #define USER_ADDRESS_SPACE_END USER_ADDRESS_SPACE_END_ARCH
65 #define USTACK_ADDRESS USTACK_ADDRESS_ARCH
67 #define FLAG_AS_KERNEL (1 << 0) /**< Kernel address space. */
69 /** Address space structure.
71 * as_t contains the list of as_areas of userspace accessible
72 * pages for one or more tasks. Ranges of kernel memory pages are not
73 * supposed to figure in the list as they are shared by all tasks and
74 * set up during system initialization.
77 /** Protected by asidlock. */
78 link_t inactive_as_with_asid_link
;
82 /** Number of references (i.e tasks that reference this as). */
85 /** Number of processors on wich is this address space active. */
88 /** B+tree of address space areas. */
89 btree_t as_area_btree
;
91 /** Page table pointer. Constant on architectures that use global page hash table. */
94 /** Address space identifier. Constant on architectures that do not support ASIDs.*/
97 #ifdef CONFIG_VIRT_IDX_DCACHE
98 bool dcache_flush_on_install
;
99 bool dcache_flush_on_deinstall
;
100 #endif /* CONFIG_VIRT_IDX_DCACHE */
102 /** Architecture specific content. */
106 struct as_operations
{
107 pte_t
*(* page_table_create
)(int flags
);
108 void (* page_table_destroy
)(pte_t
*page_table
);
109 void (* page_table_lock
)(as_t
*as
, bool lock
);
110 void (* page_table_unlock
)(as_t
*as
, bool unlock
);
112 typedef struct as_operations as_operations_t
;
114 /** Address space area attributes. */
115 #define AS_AREA_ATTR_NONE 0
116 #define AS_AREA_ATTR_PARTIAL 1 /**< Not fully initialized area. */
118 #define AS_PF_FAULT 0 /**< The page fault was not resolved by as_page_fault(). */
119 #define AS_PF_OK 1 /**< The page fault was resolved by as_page_fault(). */
120 #define AS_PF_DEFER 2 /**< The page fault was caused by memcpy_from_uspace()
121 or memcpy_to_uspace(). */
123 /** This structure contains information associated with the shared address space area. */
125 mutex_t lock
; /**< This lock must be acquired only when the as_area lock is held. */
126 count_t refcount
; /**< This structure can be deallocated if refcount drops to 0. */
127 btree_t pagemap
; /**< B+tree containing complete map of anonymous pages of the shared area. */
130 /** Address space area backend structure. */
132 int (* page_fault
)(as_area_t
*area
, uintptr_t addr
, pf_access_t access
);
133 void (* frame_free
)(as_area_t
*area
, uintptr_t page
, uintptr_t frame
);
134 void (* share
)(as_area_t
*area
);
137 /** Backend data stored in address space area. */
139 struct { /**< elf_backend members */
141 elf_segment_header_t
*segment
;
143 struct { /**< phys_backend members */
147 } mem_backend_data_t
;
149 /** Address space area structure.
151 * Each as_area_t structure describes one contiguous area of virtual memory.
152 * In the future, it should not be difficult to support shared areas.
156 as_t
*as
; /**< Containing address space. */
157 int flags
; /**< Flags related to the memory represented by the address space area. */
158 int attributes
; /**< Attributes related to the address space area itself. */
159 count_t pages
; /**< Size of this area in multiples of PAGE_SIZE. */
160 uintptr_t base
; /**< Base address of this area. */
161 btree_t used_space
; /**< Map of used space. */
162 share_info_t
*sh_info
; /**< If the address space area has been shared, this pointer will
163 reference the share info structure. */
164 mem_backend_t
*backend
; /**< Memory backend backing this address space area. */
166 /** Data to be used by the backend. */
167 mem_backend_data_t backend_data
;
170 * Virtual color of the original address space area that was at the beginning
171 * of the share chain.
176 extern as_t
*AS_KERNEL
;
177 extern as_operations_t
*as_operations
;
179 extern spinlock_t inactive_as_with_asid_lock
;
180 extern link_t inactive_as_with_asid_head
;
182 extern void as_init(void);
184 extern as_t
*as_create(int flags
);
185 extern void as_destroy(as_t
*as
);
186 extern void as_switch(as_t
*old
, as_t
*new);
187 extern int as_page_fault(uintptr_t page
, pf_access_t access
, istate_t
*istate
);
189 extern as_area_t
*as_area_create(as_t
*as
, int flags
, size_t size
, uintptr_t base
, int attrs
,
190 mem_backend_t
*backend
, mem_backend_data_t
*backend_data
);
191 extern int as_area_destroy(as_t
*as
, uintptr_t address
);
192 extern int as_area_resize(as_t
*as
, uintptr_t address
, size_t size
, int flags
);
193 int as_area_share(as_t
*src_as
, uintptr_t src_base
, size_t acc_size
,
194 as_t
*dst_as
, uintptr_t dst_base
, int dst_flags_mask
);
196 extern int as_area_get_flags(as_area_t
*area
);
197 extern bool as_area_check_access(as_area_t
*area
, pf_access_t access
);
198 extern size_t as_get_size(uintptr_t base
);
199 extern int used_space_insert(as_area_t
*a
, uintptr_t page
, count_t count
);
200 extern int used_space_remove(as_area_t
*a
, uintptr_t page
, count_t count
);
203 /* Interface to be implemented by architectures. */
204 #ifndef as_constructor_arch
205 extern int as_constructor_arch(as_t
*as
, int flags
);
206 #endif /* !def as_constructor_arch */
207 #ifndef as_destructor_arch
208 extern int as_destructor_arch(as_t
*as
);
209 #endif /* !def as_destructor_arch */
210 #ifndef as_create_arch
211 extern int as_create_arch(as_t
*as
, int flags
);
212 #endif /* !def as_create_arch */
213 #ifndef as_install_arch
214 extern void as_install_arch(as_t
*as
);
215 #endif /* !def as_install_arch */
216 #ifndef as_deinstall_arch
217 extern void as_deinstall_arch(as_t
*as
);
218 #endif /* !def as_deinstall_arch */
220 /* Backend declarations. */
221 extern mem_backend_t anon_backend
;
222 extern mem_backend_t elf_backend
;
223 extern mem_backend_t phys_backend
;
225 /* Address space area related syscalls. */
226 extern unative_t
sys_as_area_create(uintptr_t address
, size_t size
, int flags
);
227 extern unative_t
sys_as_area_resize(uintptr_t address
, size_t size
, int flags
);
228 extern unative_t
sys_as_area_destroy(uintptr_t address
);
230 /* Introspection functions. */
231 extern void as_print(as_t
*as
);