WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/mm/as.c


/*
 * Copyright (C) 2001-2006 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */
 
/*
 * This file contains address space manipulation functions.
 * Roughly speaking, this is a higher-level client of
 * Virtual Address Translation (VAT) subsystem.
 */
 
#include <mm/as.h>
#include <arch/mm/as.h>
#include <mm/page.h>
#include <mm/frame.h>
#include <mm/tlb.h>
#include <mm/heap.h>
#include <arch/mm/page.h>
#include <genarch/mm/page_pt.h>
#include <mm/asid.h>
#include <arch/mm/asid.h>
 
#include <arch/types.h>
#include <typedefs.h>
#include <synch/spinlock.h>
#include <config.h>
#include <list.h>
#include <panic.h>
#include <arch/asm.h>
#include <debug.h>
#include <memstr.h>
#include <arch.h>
#include <print.h>
 
 
 
as_operations_t *as_operations = NULL;
 
static int get_area_flags(as_area_t *a);
 
/** Initialize address space subsystem. */
void as_init(void)
{
    as_arch_init();
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
        if (!AS_KERNEL)
                panic("can't create kernel address space\n");
}
 
/** Create address space. */
 
 
 
 
as_t *as_create(int flags)
{
    as_t *as;
 
    as = (as_t *) malloc(sizeof(as_t));
    if (as) {
        list_initialize(&as->as_with_asid_link);
        spinlock_initialize(&as->lock, "as_lock");
        list_initialize(&as->as_area_head);
 
        if (flags & FLAG_AS_KERNEL)
            as->asid = ASID_KERNEL;
        else
            as->asid = ASID_INVALID;
 
 
 
 
 
 
 
 
 
 
 
 
 
        as->page_table = page_table_create(flags);
 
    }
 
    return as;
}
 
/** Create address space area of common attributes.
 *
 * The created address space area is added to the target address space.
 *
 * @param as Target address space.
 * @param type Type of area.
 * @param size Size of area in multiples of PAGE_SIZE.
 * @param base Base address of area.
 *
 * @return Address space area on success or NULL on failure.
 */
as_area_t *as_area_create(as_t *as, as_area_type_t type, size_t size, __address base)
{
    ipl_t ipl;
    as_area_t *a;
   
    if (base % PAGE_SIZE)
        panic("addr not aligned to a page boundary");
   
    ipl = interrupts_disable();
    spinlock_lock(&as->lock);
   
    /*
     * TODO: test as_area which is to be created doesn't overlap with an existing one.
     */
   
    a = (as_area_t *) malloc(sizeof(as_area_t));
    if (a) {   
        spinlock_initialize(&a->lock, "as_area_lock");
           
        link_initialize(&a->link);         
        a->type = type;
        a->size = size;
        a->base = base;
       
        list_append(&a->link, &as->as_area_head);
    }
 
    spinlock_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return a;
}
 
/** Initialize mapping for one page of address space.
 *
 * This functions maps 'page' to 'frame' according
 * to attributes of the address space area to
 * wich 'page' belongs.
 *
 * @param a Target address space.
 * @param page Virtual page within the area.
 * @param frame Physical frame to which page will be mapped.
 */
void as_set_mapping(as_t *as, __address page, __address frame)
{
    as_area_t *a, *area = NULL;
    link_t *cur;
    ipl_t ipl;
   
    ipl = interrupts_disable();
    spinlock_lock(&as->lock);
   
    /*
     * First, try locate an area.
     */
    for (cur = as->as_area_head.next; cur != &as->as_area_head; cur = cur->next) {
        a = list_get_instance(cur, as_area_t, link);
        spinlock_lock(&a->lock);
 
        if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) {
            area = a;
            break;
        }
       
        spinlock_unlock(&a->lock);
    }
   
    if (!area) {
        panic("page not part of any as_area\n");
    }
 
    /*
     * Note: area->lock is held.
     */
   
    page_mapping_insert(as, page, frame, get_area_flags(area));
   
    spinlock_unlock(&area->lock);
    spinlock_unlock(&as->lock);
    interrupts_restore(ipl);
}
 
/** Handle page fault within the current address space.
 *
 * This is the high-level page fault handler.
 * Interrupts are assumed disabled.
 *
 * @param page Faulting page.
 *
 * @return 0 on page fault, 1 on success.
 */
int as_page_fault(__address page)
{
    link_t *cur;
    as_area_t *a, *area = NULL;
    __address frame;
   
    ASSERT(AS);
    spinlock_lock(&AS->lock);
   
    /*
     * Search this areas of this address space for presence of 'page'.
     */
    for (cur = AS->as_area_head.next; cur != &AS->as_area_head; cur = cur->next) {
        a = list_get_instance(cur, as_area_t, link);
        spinlock_lock(&a->lock);
 
        if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) {
 
            /*
             * We found the area containing 'page'.
             * TODO: access checking
             */
            area = a;
            break;
        }
       
        spinlock_unlock(&a->lock);
    }
   
    if (!area) {
        /*
         * No area contained mapping for 'page'.
         * Signal page fault to low-level handler.
         */
        spinlock_unlock(&AS->lock);
        return 0;
    }
 
    /*
     * Note: area->lock is held.
     */
   
    /*
     * In general, there can be several reasons that
     * can have caused this fault.
     *
     * - non-existent mapping: the area is a scratch
     *   area (e.g. stack) and so far has not been
     *   allocated a frame for the faulting page
     *
     * - non-present mapping: another possibility,
     *   currently not implemented, would be frame
     *   reuse; when this becomes a possibility,
     *   do not forget to distinguish between
     *   the different causes
     */
    frame = frame_alloc(0, ONE_FRAME, NULL);
    memsetb(PA2KA(frame), FRAME_SIZE, 0);
   
    /*
     * Map 'page' to 'frame'.
     * Note that TLB shootdown is not attempted as only new information is being
     * inserted into page tables.
     */
    page_mapping_insert(AS, page, frame, get_area_flags(area));
   
    spinlock_unlock(&area->lock);
    spinlock_unlock(&AS->lock);
 
    return 1;
}
 
/** Install address space on CPU.
 *
 * @param as Address space.
 */
void as_install(as_t *as)
{
    ipl_t ipl;
   
    asid_install(as);
   
    ipl = interrupts_disable();
    spinlock_lock(&as->lock);
    ASSERT(as->page_table);
    SET_PTL0_ADDRESS(as->page_table);
    spinlock_unlock(&as->lock);
    interrupts_restore(ipl);
 
    /*
     * Perform architecture-specific steps.
     * (e.g. write ASID to hardware register etc.)
     */
    as_install_arch(as);
   
    AS = as;
}
 
/** Compute flags for virtual address translation subsytem.
 *
 * The address space area must be locked.
 * Interrupts must be disabled.
 *
 * @param a Address space area.
 *
 * @return Flags to be used in page_mapping_insert().
 */
int get_area_flags(as_area_t *a)
{
    int flags;
 
    switch (a->type) {
        case AS_AREA_TEXT:
            flags = PAGE_EXEC | PAGE_READ | PAGE_USER | PAGE_PRESENT | PAGE_CACHEABLE;
            break;
        case AS_AREA_DATA:
        case AS_AREA_STACK:
            flags = PAGE_READ | PAGE_WRITE | PAGE_USER | PAGE_PRESENT | PAGE_CACHEABLE;
            break;
        default:
            panic("unexpected as_area_type_t %d", a->type);
    }
   
    return flags;
}
 
/** Create page table.
 *
 * Depending on architecture, create either address space
 * private or global page table.
 *
 * @param flags Flags saying whether the page table is for kernel address space.
 *
 * @return First entry of the page table.
 */
pte_t *page_table_create(int flags)
{
        ASSERT(as_operations);
        ASSERT(as_operations->page_table_create);
 
        return as_operations->page_table_create(flags);
}
 

Rev 755	Rev 756
1	/*	1	/*
2	* Copyright (C) 2001-2006 Jakub Jermar	2	* Copyright (C) 2001-2006 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	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	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.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	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	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	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	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	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	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.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/*	29	/*
30	* This file contains address space manipulation functions.	30	* This file contains address space manipulation functions.
31	* Roughly speaking, this is a higher-level client of	31	* Roughly speaking, this is a higher-level client of
32	* Virtual Address Translation (VAT) subsystem.	32	* Virtual Address Translation (VAT) subsystem.
33	*/	33	*/
34		34
35	#include <mm/as.h>	35	#include <mm/as.h>
36	#include <mm/asid.h>	36	#include <arch/mm/as.h>
37	#include <mm/page.h>	37	#include <mm/page.h>
38	#include <mm/frame.h>	38	#include <mm/frame.h>
39	#include <mm/tlb.h>	39	#include <mm/tlb.h>
40	#include <mm/heap.h>	40	#include <mm/heap.h>
41	#include <arch/mm/page.h>	41	#include <arch/mm/page.h>
42	#include <genarch/mm/page_pt.h>	42	#include <genarch/mm/page_pt.h>
43	#include <mm/asid.h>	43	#include <mm/asid.h>
44	#include <arch/mm/asid.h>	44	#include <arch/mm/asid.h>
45	#include <arch/mm/as.h>	-
46	#include <arch/types.h>	45	#include <arch/types.h>
47	#include <typedefs.h>	46	#include <typedefs.h>
48	#include <synch/spinlock.h>	47	#include <synch/spinlock.h>
49	#include <config.h>	48	#include <config.h>
50	#include <list.h>	49	#include <list.h>
51	#include <panic.h>	50	#include <panic.h>
52	#include <arch/asm.h>	51	#include <arch/asm.h>
53	#include <debug.h>	52	#include <debug.h>
54	#include <memstr.h>	53	#include <memstr.h>
55	#include <arch.h>	54	#include <arch.h>
56	#include <print.h>	55	#include <print.h>
57		56
58	#define KAS_START_INDEX PTL0_INDEX(KERNEL_ADDRESS_SPACE_START)	-
59	#define KAS_END_INDEX PTL0_INDEX(KERNEL_ADDRESS_SPACE_END)	-
60	#define KAS_INDICES (1+(KAS_END_INDEX-KAS_START_INDEX))	57	as_operations_t *as_operations = NULL;
61		58
62	static int get_area_flags(as_area_t *a);	59	static int get_area_flags(as_area_t *a);
63		60
-		61	/** Initialize address space subsystem. */
-		62	void as_init(void)
-		63	{
-		64	as_arch_init();
-		65	AS_KERNEL = as_create(FLAG_AS_KERNEL);
-		66	if (!AS_KERNEL)
-		67	panic("can't create kernel address space\n");
-		68	}
-		69
64	/** Create address space. */	70	/** Create address space. */
65	/*	-
66	* FIXME: this interface must be meaningful for all possible VAT	-
67	* (Virtual Address Translation) mechanisms.	-
68	*/	-
69	as_t as_create(pte_t ptl0, int flags)	71	as_t *as_create(int flags)
70	{	72	{
71	as_t *as;	73	as_t *as;
72		74
73	as = (as_t *) malloc(sizeof(as_t));	75	as = (as_t *) malloc(sizeof(as_t));
74	if (as) {	76	if (as) {
75	list_initialize(&as->as_with_asid_link);	77	list_initialize(&as->as_with_asid_link);
76	spinlock_initialize(&as->lock, "as_lock");	78	spinlock_initialize(&as->lock, "as_lock");
77	list_initialize(&as->as_area_head);	79	list_initialize(&as->as_area_head);
78		80
79	if (flags & FLAG_AS_KERNEL)	81	if (flags & FLAG_AS_KERNEL)
80	as->asid = ASID_KERNEL;	82	as->asid = ASID_KERNEL;
81	else	83	else
82	as->asid = ASID_INVALID;	84	as->asid = ASID_INVALID;
83		85
84	as->ptl0 = ptl0;	-
85	if (!as->ptl0) {	-
86	pte_t src_ptl0, dst_ptl0;	-
87		-
88	src_ptl0 = (pte_t *) PA2KA((__address) GET_PTL0_ADDRESS());	-
89	dst_ptl0 = (pte_t *) frame_alloc(FRAME_KA \| FRAME_PANIC, ONE_FRAME, NULL);	-
90		-
91	// memsetb((__address) dst_ptl0, PAGE_SIZE, 0);	-
92	// memcpy((void ) &dst_ptl0[KAS_START_INDEX], (void ) &src_ptl0[KAS_START_INDEX], KAS_INDICES);	-
93		-
94	memcpy((void ) dst_ptl0,(void ) src_ptl0, PAGE_SIZE);	-
95		-
96	as->ptl0 = (pte_t *) KA2PA((__address) dst_ptl0);	86	as->page_table = page_table_create(flags);
97	}	-
98	}	87	}
99		88
100	return as;	89	return as;
101	}	90	}
102		91
103	/** Create address space area of common attributes.	92	/** Create address space area of common attributes.
104	*	93	*
105	* The created address space area is added to the target address space.	94	* The created address space area is added to the target address space.
106	*	95	*
107	* @param as Target address space.	96	* @param as Target address space.
108	* @param type Type of area.	97	* @param type Type of area.
109	* @param size Size of area in multiples of PAGE_SIZE.	98	* @param size Size of area in multiples of PAGE_SIZE.
110	* @param base Base address of area.	99	* @param base Base address of area.
111	*	100	*
112	* @return Address space area on success or NULL on failure.	101	* @return Address space area on success or NULL on failure.
113	*/	102	*/
114	as_area_t as_area_create(as_t as, as_area_type_t type, size_t size, __address base)	103	as_area_t as_area_create(as_t as, as_area_type_t type, size_t size, __address base)
115	{	104	{
116	ipl_t ipl;	105	ipl_t ipl;
117	as_area_t *a;	106	as_area_t *a;
118		107
119	if (base % PAGE_SIZE)	108	if (base % PAGE_SIZE)
120	panic("addr not aligned to a page boundary");	109	panic("addr not aligned to a page boundary");
121		110
122	ipl = interrupts_disable();	111	ipl = interrupts_disable();
123	spinlock_lock(&as->lock);	112	spinlock_lock(&as->lock);
124		113
125	/*	114	/*
126	* TODO: test as_area which is to be created doesn't overlap with an existing one.	115	* TODO: test as_area which is to be created doesn't overlap with an existing one.
127	*/	116	*/
128		117
129	a = (as_area_t *) malloc(sizeof(as_area_t));	118	a = (as_area_t *) malloc(sizeof(as_area_t));
130	if (a) {	119	if (a) {
131	spinlock_initialize(&a->lock, "as_area_lock");	120	spinlock_initialize(&a->lock, "as_area_lock");
132		121
133	link_initialize(&a->link);	122	link_initialize(&a->link);
134	a->type = type;	123	a->type = type;
135	a->size = size;	124	a->size = size;
136	a->base = base;	125	a->base = base;
137		126
138	list_append(&a->link, &as->as_area_head);	127	list_append(&a->link, &as->as_area_head);
139	}	128	}
140		129
141	spinlock_unlock(&as->lock);	130	spinlock_unlock(&as->lock);
142	interrupts_restore(ipl);	131	interrupts_restore(ipl);
143		132
144	return a;	133	return a;
145	}	134	}
146		135
147	/** Initialize mapping for one page of address space.	136	/** Initialize mapping for one page of address space.
148	*	137	*
149	* This functions maps 'page' to 'frame' according	138	* This functions maps 'page' to 'frame' according
150	* to attributes of the address space area to	139	* to attributes of the address space area to
151	* wich 'page' belongs.	140	* wich 'page' belongs.
152	*	141	*
153	* @param a Target address space.	142	* @param a Target address space.
154	* @param page Virtual page within the area.	143	* @param page Virtual page within the area.
155	* @param frame Physical frame to which page will be mapped.	144	* @param frame Physical frame to which page will be mapped.
156	*/	145	*/
157	void as_set_mapping(as_t *as, __address page, __address frame)	146	void as_set_mapping(as_t *as, __address page, __address frame)
158	{	147	{
159	as_area_t a, area = NULL;	148	as_area_t a, area = NULL;
160	link_t *cur;	149	link_t *cur;
161	ipl_t ipl;	150	ipl_t ipl;
162		151
163	ipl = interrupts_disable();	152	ipl = interrupts_disable();
164	spinlock_lock(&as->lock);	153	spinlock_lock(&as->lock);
165		154
166	/*	155	/*
167	* First, try locate an area.	156	* First, try locate an area.
168	*/	157	*/
169	for (cur = as->as_area_head.next; cur != &as->as_area_head; cur = cur->next) {	158	for (cur = as->as_area_head.next; cur != &as->as_area_head; cur = cur->next) {
170	a = list_get_instance(cur, as_area_t, link);	159	a = list_get_instance(cur, as_area_t, link);
171	spinlock_lock(&a->lock);	160	spinlock_lock(&a->lock);
172		161
173	if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) {	162	if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) {
174	area = a;	163	area = a;
175	break;	164	break;
176	}	165	}
177		166
178	spinlock_unlock(&a->lock);	167	spinlock_unlock(&a->lock);
179	}	168	}
180		169
181	if (!area) {	170	if (!area) {
182	panic("page not part of any as_area\n");	171	panic("page not part of any as_area\n");
183	}	172	}
184		173
185	/*	174	/*
186	* Note: area->lock is held.	175	* Note: area->lock is held.
187	*/	176	*/
188		177
189	page_mapping_insert(as, page, frame, get_area_flags(area), (__address) as->ptl0);	178	page_mapping_insert(as, page, frame, get_area_flags(area));
190		179
191	spinlock_unlock(&area->lock);	180	spinlock_unlock(&area->lock);
192	spinlock_unlock(&as->lock);	181	spinlock_unlock(&as->lock);
193	interrupts_restore(ipl);	182	interrupts_restore(ipl);
194	}	183	}
195		184
196	/** Handle page fault within the current address space.	185	/** Handle page fault within the current address space.
197	*	186	*
198	* This is the high-level page fault handler.	187	* This is the high-level page fault handler.
199	* Interrupts are assumed disabled.	188	* Interrupts are assumed disabled.
200	*	189	*
201	* @param page Faulting page.	190	* @param page Faulting page.
202	*	191	*
203	* @return 0 on page fault, 1 on success.	192	* @return 0 on page fault, 1 on success.
204	*/	193	*/
205	int as_page_fault(__address page)	194	int as_page_fault(__address page)
206	{	195	{
207	link_t *cur;	196	link_t *cur;
208	as_area_t a, area = NULL;	197	as_area_t a, area = NULL;
209	__address frame;	198	__address frame;
210		199
211	ASSERT(AS);	200	ASSERT(AS);
212	spinlock_lock(&AS->lock);	201	spinlock_lock(&AS->lock);
213		202
214	/*	203	/*
215	* Search this areas of this address space for presence of 'page'.	204	* Search this areas of this address space for presence of 'page'.
216	*/	205	*/
217	for (cur = AS->as_area_head.next; cur != &AS->as_area_head; cur = cur->next) {	206	for (cur = AS->as_area_head.next; cur != &AS->as_area_head; cur = cur->next) {
218	a = list_get_instance(cur, as_area_t, link);	207	a = list_get_instance(cur, as_area_t, link);
219	spinlock_lock(&a->lock);	208	spinlock_lock(&a->lock);
220		209
221	if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) {	210	if ((page >= a->base) && (page < a->base + a->size * PAGE_SIZE)) {
222		211
223	/*	212	/*
224	* We found the area containing 'page'.	213	* We found the area containing 'page'.
225	* TODO: access checking	214	* TODO: access checking
226	*/	215	*/
227	area = a;	216	area = a;
228	break;	217	break;
229	}	218	}
230		219
231	spinlock_unlock(&a->lock);	220	spinlock_unlock(&a->lock);
232	}	221	}
233		222
234	if (!area) {	223	if (!area) {
235	/*	224	/*
236	* No area contained mapping for 'page'.	225	* No area contained mapping for 'page'.
237	* Signal page fault to low-level handler.	226	* Signal page fault to low-level handler.
238	*/	227	*/
239	spinlock_unlock(&AS->lock);	228	spinlock_unlock(&AS->lock);
240	return 0;	229	return 0;
241	}	230	}
242		231
243	/*	232	/*
244	* Note: area->lock is held.	233	* Note: area->lock is held.
245	*/	234	*/
246		235
247	/*	236	/*
248	* In general, there can be several reasons that	237	* In general, there can be several reasons that
249	* can have caused this fault.	238	* can have caused this fault.
250	*	239	*
251	* - non-existent mapping: the area is a scratch	240	* - non-existent mapping: the area is a scratch
252	* area (e.g. stack) and so far has not been	241	* area (e.g. stack) and so far has not been
253	* allocated a frame for the faulting page	242	* allocated a frame for the faulting page
254	*	243	*
255	* - non-present mapping: another possibility,	244	* - non-present mapping: another possibility,
256	* currently not implemented, would be frame	245	* currently not implemented, would be frame
257	* reuse; when this becomes a possibility,	246	* reuse; when this becomes a possibility,
258	* do not forget to distinguish between	247	* do not forget to distinguish between
259	* the different causes	248	* the different causes
260	*/	249	*/
261	frame = frame_alloc(0, ONE_FRAME, NULL);	250	frame = frame_alloc(0, ONE_FRAME, NULL);
262	memsetb(PA2KA(frame), FRAME_SIZE, 0);	251	memsetb(PA2KA(frame), FRAME_SIZE, 0);
263		252
264	/*	253	/*
265	* Map 'page' to 'frame'.	254	* Map 'page' to 'frame'.
266	* Note that TLB shootdown is not attempted as only new information is being	255	* Note that TLB shootdown is not attempted as only new information is being
267	* inserted into page tables.	256	* inserted into page tables.
268	*/	257	*/
269	page_mapping_insert(AS, page, frame, get_area_flags(area), (__address) AS->ptl0);	258	page_mapping_insert(AS, page, frame, get_area_flags(area));
270		259
271	spinlock_unlock(&area->lock);	260	spinlock_unlock(&area->lock);
272	spinlock_unlock(&AS->lock);	261	spinlock_unlock(&AS->lock);
273		262
274	return 1;	263	return 1;
275	}	264	}
276		265
277	/** Install address space on CPU.	266	/** Install address space on CPU.
278	*	267	*
279	* @param as Address space.	268	* @param as Address space.
280	*/	269	*/
281	void as_install(as_t *as)	270	void as_install(as_t *as)
282	{	271	{
283	ipl_t ipl;	272	ipl_t ipl;
284		273
285	asid_install(as);	274	asid_install(as);
286		275
287	ipl = interrupts_disable();	276	ipl = interrupts_disable();
288	spinlock_lock(&as->lock);	277	spinlock_lock(&as->lock);
289	ASSERT(as->ptl0);	278	ASSERT(as->page_table);
290	SET_PTL0_ADDRESS(as->ptl0);	279	SET_PTL0_ADDRESS(as->page_table);
291	spinlock_unlock(&as->lock);	280	spinlock_unlock(&as->lock);
292	interrupts_restore(ipl);	281	interrupts_restore(ipl);
293		282
294	/*	283	/*
295	* Perform architecture-specific steps.	284	* Perform architecture-specific steps.
296	* (e.g. write ASID to hardware register etc.)	285	* (e.g. write ASID to hardware register etc.)
297	*/	286	*/
298	as_install_arch(as);	287	as_install_arch(as);
299		288
300	AS = as;	289	AS = as;
301	}	290	}
302		291
303	/** Compute flags for virtual address translation subsytem.	292	/** Compute flags for virtual address translation subsytem.
304	*	293	*
305	* The address space area must be locked.	294	* The address space area must be locked.
306	* Interrupts must be disabled.	295	* Interrupts must be disabled.
307	*	296	*
308	* @param a Address space area.	297	* @param a Address space area.
309	*	298	*
310	* @return Flags to be used in page_mapping_insert().	299	* @return Flags to be used in page_mapping_insert().
311	*/	300	*/
312	int get_area_flags(as_area_t *a)	301	int get_area_flags(as_area_t *a)
313	{	302	{
314	int flags;	303	int flags;
315		304
316	switch (a->type) {	305	switch (a->type) {
317	case AS_AREA_TEXT:	306	case AS_AREA_TEXT:
318	flags = PAGE_EXEC \| PAGE_READ \| PAGE_USER \| PAGE_PRESENT \| PAGE_CACHEABLE;	307	flags = PAGE_EXEC \| PAGE_READ \| PAGE_USER \| PAGE_PRESENT \| PAGE_CACHEABLE;
319	break;	308	break;
320	case AS_AREA_DATA:	309	case AS_AREA_DATA:
321	case AS_AREA_STACK:	310	case AS_AREA_STACK:
322	flags = PAGE_READ \| PAGE_WRITE \| PAGE_USER \| PAGE_PRESENT \| PAGE_CACHEABLE;	311	flags = PAGE_READ \| PAGE_WRITE \| PAGE_USER \| PAGE_PRESENT \| PAGE_CACHEABLE;
323	break;	312	break;
324	default:	313	default:
325	panic("unexpected as_area_type_t %d", a->type);	314	panic("unexpected as_area_type_t %d", a->type);
326	}	315	}
327		316
328	return flags;	317	return flags;
329	}	318	}
-		319
-		320	/** Create page table.
-		321	*
-		322	* Depending on architecture, create either address space
-		323	* private or global page table.
-		324	*
-		325	* @param flags Flags saying whether the page table is for kernel address space.
-		326	*
-		327	* @return First entry of the page table.
-		328	*/
-		329	pte_t *page_table_create(int flags)
-		330	{
-		331	ASSERT(as_operations);
-		332	ASSERT(as_operations->page_table_create);
-		333
-		334	return as_operations->page_table_create(flags);
-		335	}
330		336

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(root)/kernel/trunk/generic/src/mm/as.c @ 1760 – Rev 755 → 756