WebSVN – HelenOS – Diff – /branches/network/kernel/genarch/src/mm/page_ht.c


/*
 * Copyright (c) 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.
 */
 
/** @addtogroup genarchmm
 * @{
 */
 
/**
 * @file
 * @brief   Virtual Address Translation (VAT) for global page hash table.
 */
 
#include <genarch/mm/page_ht.h>
#include <mm/page.h>
#include <arch/mm/page.h>
#include <mm/frame.h>
#include <mm/slab.h>
#include <mm/as.h>
#include <arch/mm/asid.h>
#include <arch/types.h>
#include <arch/asm.h>
#include <synch/spinlock.h>
#include <arch.h>
#include <debug.h>
#include <memstr.h>
#include <adt/hash_table.h>
#include <align.h>
 
static size_t hash(unative_t key[]);
static bool compare(unative_t key[], size_t keys, link_t *item);
static void remove_callback(link_t *item);
 
static void ht_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame,
    int flags);
static void ht_mapping_remove(as_t *as, uintptr_t page);
static pte_t *ht_mapping_find(as_t *as, uintptr_t page);
 
/**
 * This lock protects the page hash table. It must be acquired
 * after address space lock and after any address space area
 * locks.
 */
mutex_t page_ht_lock;
 
/**
 * Page hash table.
 * The page hash table may be accessed only when page_ht_lock is held.
 */
hash_table_t page_ht;
 
/** Hash table operations for page hash table. */
hash_table_operations_t ht_operations = {
    .hash = hash,
    .compare = compare,
    .remove_callback = remove_callback
};
 
/** Page mapping operations for page hash table architectures. */
page_mapping_operations_t ht_mapping_operations = {
    .mapping_insert = ht_mapping_insert,
    .mapping_remove = ht_mapping_remove,
    .mapping_find = ht_mapping_find
};
 
/** Compute page hash table index.
 *
 * @param key Array of two keys (i.e. page and address space).
 *
 * @return Index into page hash table.
 */
size_t hash(unative_t key[])
{
    as_t *as = (as_t *) key[KEY_AS];
    uintptr_t page = (uintptr_t) key[KEY_PAGE];
    size_t index;
   
    /*
     * Virtual page addresses have roughly the same probability
     * of occurring. Least significant bits of VPN compose the
     * hash index.
     */
    index = ((page >> PAGE_WIDTH) & (PAGE_HT_ENTRIES - 1));
   
    /*
     * Address space structures are likely to be allocated from
     * similar addresses. Least significant bits compose the
     * hash index.
     */
    index |= ((unative_t) as) & (PAGE_HT_ENTRIES - 1);
   
    return index;
}
 
/** Compare page hash table item with page and/or address space.
 *
 * @param key Array of one or two keys (i.e. page and/or address space).
 * @param keys Number of keys passed.
 * @param item Item to compare the keys with.
 *
 * @return true on match, false otherwise.
 */
bool compare(unative_t key[], size_t keys, link_t *item)
{
    pte_t *t;
 
    ASSERT(item);
    ASSERT((keys > 0) && (keys <= PAGE_HT_KEYS));
 
    /*
     * Convert item to PTE.
     */
    t = hash_table_get_instance(item, pte_t, link);
 
    if (keys == PAGE_HT_KEYS) {
        return (key[KEY_AS] == (uintptr_t) t->as) &&
            (key[KEY_PAGE] == t->page);
    } else {
        return (key[KEY_AS] == (uintptr_t) t->as);
    }
}
 
/** Callback on page hash table item removal.
 *
 * @param item Page hash table item being removed.
 */
void remove_callback(link_t *item)
{
    pte_t *t;
 
    ASSERT(item);
 
    /*
     * Convert item to PTE.
     */
    t = hash_table_get_instance(item, pte_t, link);
 
    free(t);
}
 
/** Map page to frame using page hash table.
 *
 * Map virtual address page to physical address frame
 * using flags.
 *
 * The page table must be locked and interrupts must be disabled.
 *
 * @param as Address space to which page belongs.
 * @param page Virtual address of the page to be mapped.
 * @param frame Physical address of memory frame to which the mapping is done.
 * @param flags Flags to be used for mapping.
 */
void ht_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame, int flags)
{
    pte_t *t;
    unative_t key[2] = {
        (uintptr_t) as,
        page = ALIGN_DOWN(page, PAGE_SIZE)
    };
   
    if (!hash_table_find(&page_ht, key)) {
        t = (pte_t *) malloc(sizeof(pte_t), FRAME_ATOMIC);
        ASSERT(t != NULL);
 
        t->g = (flags & PAGE_GLOBAL) != 0;
        t->x = (flags & PAGE_EXEC) != 0;
        t->w = (flags & PAGE_WRITE) != 0;
        t->k = !(flags & PAGE_USER);
        t->c = (flags & PAGE_CACHEABLE) != 0;
        t->p = !(flags & PAGE_NOT_PRESENT);
        t->a = false;
        t->d = false;
 
        t->as = as;
        t->page = ALIGN_DOWN(page, PAGE_SIZE);
        t->frame = ALIGN_DOWN(frame, FRAME_SIZE);
 
        hash_table_insert(&page_ht, key, &t->link);
    }
}
 
/** Remove mapping of page from page hash table.
 *
 * Remove any mapping of page within address space as.
 * TLB shootdown should follow in order to make effects of
 * this call visible.
 *
 * The page table must be locked and interrupts must be disabled.
 *
 * @param as Address space to wich page belongs.
 * @param page Virtual address of the page to be demapped.
 */
void ht_mapping_remove(as_t *as, uintptr_t page)
{
    unative_t key[2] = {
        (uintptr_t) as,
        page = ALIGN_DOWN(page, PAGE_SIZE)
    };
   
    /*
     * Note that removed PTE's will be freed
     * by remove_callback().
     */
    hash_table_remove(&page_ht, key, 2);
}
 
 
/** Find mapping for virtual page in page hash table.
 *
 * Find mapping for virtual page.
 *
 * The page table must be locked and interrupts must be disabled.
 *
 * @param as Address space to wich page belongs.
 * @param page Virtual page.
 *
 * @return NULL if there is no such mapping; requested mapping otherwise.
 */
pte_t *ht_mapping_find(as_t *as, uintptr_t page)
{
    link_t *hlp;
    pte_t *t = NULL;
    unative_t key[2] = {
        (uintptr_t) as,
        page = ALIGN_DOWN(page, PAGE_SIZE)
    };
   
    hlp = hash_table_find(&page_ht, key);
    if (hlp)
        t = hash_table_get_instance(hlp, pte_t, link);
 
    return t;
}
 
/** @}
 */
 

Subversion Repositories HelenOS

(root)/branches/network/kernel/genarch/src/mm/page_ht.c – Rev 4581 → 4718

Rev 4581		Rev 4718
1	/*	1	/*
2	* Copyright (c) 2006 Jakub Jermar	2	* Copyright (c) 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	/** @addtogroup genarchmm	29	/** @addtogroup genarchmm
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file	34	* @file
35	* @brief Virtual Address Translation (VAT) for global page hash table.	35	* @brief Virtual Address Translation (VAT) for global page hash table.
36	*/	36	*/
37		37
38	#include <genarch/mm/page_ht.h>	38	#include <genarch/mm/page_ht.h>
39	#include <mm/page.h>	39	#include <mm/page.h>
40	#include <arch/mm/page.h>	40	#include <arch/mm/page.h>
41	#include <mm/frame.h>	41	#include <mm/frame.h>
42	#include <mm/slab.h>	42	#include <mm/slab.h>
43	#include <mm/as.h>	43	#include <mm/as.h>
44	#include <arch/mm/asid.h>	44	#include <arch/mm/asid.h>
45	#include <arch/types.h>	45	#include <arch/types.h>
46	#include <arch/asm.h>	46	#include <arch/asm.h>
47	#include <synch/spinlock.h>	47	#include <synch/spinlock.h>
48	#include <arch.h>	48	#include <arch.h>
49	#include <debug.h>	49	#include <debug.h>
50	#include <memstr.h>	50	#include <memstr.h>
51	#include <adt/hash_table.h>	51	#include <adt/hash_table.h>
52	#include <align.h>	52	#include <align.h>
53		53
54	static size_t hash(unative_t key[]);	54	static size_t hash(unative_t key[]);
55	static bool compare(unative_t key[], size_t keys, link_t *item);	55	static bool compare(unative_t key[], size_t keys, link_t *item);
56	static void remove_callback(link_t *item);	56	static void remove_callback(link_t *item);
57		57
58	static void ht_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame,	58	static void ht_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame,
59	int flags);	59	int flags);
60	static void ht_mapping_remove(as_t *as, uintptr_t page);	60	static void ht_mapping_remove(as_t *as, uintptr_t page);
61	static pte_t ht_mapping_find(as_t as, uintptr_t page);	61	static pte_t ht_mapping_find(as_t as, uintptr_t page);
62		62
63	/**	63	/**
64	* This lock protects the page hash table. It must be acquired	64	* This lock protects the page hash table. It must be acquired
65	* after address space lock and after any address space area	65	* after address space lock and after any address space area
66	* locks.	66	* locks.
67	*/	67	*/
68	mutex_t page_ht_lock;	68	mutex_t page_ht_lock;
69		69
70	/**	70	/**
71	* Page hash table.	71	* Page hash table.
72	* The page hash table may be accessed only when page_ht_lock is held.	72	* The page hash table may be accessed only when page_ht_lock is held.
73	*/	73	*/
74	hash_table_t page_ht;	74	hash_table_t page_ht;
75		75
76	/** Hash table operations for page hash table. */	76	/** Hash table operations for page hash table. */
77	hash_table_operations_t ht_operations = {	77	hash_table_operations_t ht_operations = {
78	.hash = hash,	78	.hash = hash,
79	.compare = compare,	79	.compare = compare,
80	.remove_callback = remove_callback	80	.remove_callback = remove_callback
81	};	81	};
82		82
83	/** Page mapping operations for page hash table architectures. */	83	/** Page mapping operations for page hash table architectures. */
84	page_mapping_operations_t ht_mapping_operations = {	84	page_mapping_operations_t ht_mapping_operations = {
85	.mapping_insert = ht_mapping_insert,	85	.mapping_insert = ht_mapping_insert,
86	.mapping_remove = ht_mapping_remove,	86	.mapping_remove = ht_mapping_remove,
87	.mapping_find = ht_mapping_find	87	.mapping_find = ht_mapping_find
88	};	88	};
89		89
90	/** Compute page hash table index.	90	/** Compute page hash table index.
91	*	91	*
92	* @param key Array of two keys (i.e. page and address space).	92	* @param key Array of two keys (i.e. page and address space).
93	*	93	*
94	* @return Index into page hash table.	94	* @return Index into page hash table.
95	*/	95	*/
96	size_t hash(unative_t key[])	96	size_t hash(unative_t key[])
97	{	97	{
98	as_t as = (as_t ) key[KEY_AS];	98	as_t as = (as_t ) key[KEY_AS];
99	uintptr_t page = (uintptr_t) key[KEY_PAGE];	99	uintptr_t page = (uintptr_t) key[KEY_PAGE];
100	size_t index;	100	size_t index;
101		101
102	/*	102	/*
103	* Virtual page addresses have roughly the same probability	103	* Virtual page addresses have roughly the same probability
104	* of occurring. Least significant bits of VPN compose the	104	* of occurring. Least significant bits of VPN compose the
105	* hash index.	105	* hash index.
106	*/	106	*/
107	index = ((page >> PAGE_WIDTH) & (PAGE_HT_ENTRIES - 1));	107	index = ((page >> PAGE_WIDTH) & (PAGE_HT_ENTRIES - 1));
108		108
109	/*	109	/*
110	* Address space structures are likely to be allocated from	110	* Address space structures are likely to be allocated from
111	* similar addresses. Least significant bits compose the	111	* similar addresses. Least significant bits compose the
112	* hash index.	112	* hash index.
113	*/	113	*/
114	index \|= ((unative_t) as) & (PAGE_HT_ENTRIES - 1);	114	index \|= ((unative_t) as) & (PAGE_HT_ENTRIES - 1);
115		115
116	return index;	116	return index;
117	}	117	}
118		118
119	/** Compare page hash table item with page and/or address space.	119	/** Compare page hash table item with page and/or address space.
120	*	120	*
121	* @param key Array of one or two keys (i.e. page and/or address space).	121	* @param key Array of one or two keys (i.e. page and/or address space).
122	* @param keys Number of keys passed.	122	* @param keys Number of keys passed.
123	* @param item Item to compare the keys with.	123	* @param item Item to compare the keys with.
124	*	124	*
125	* @return true on match, false otherwise.	125	* @return true on match, false otherwise.
126	*/	126	*/
127	bool compare(unative_t key[], size_t keys, link_t *item)	127	bool compare(unative_t key[], size_t keys, link_t *item)
128	{	128	{
129	pte_t *t;	129	pte_t *t;
130		130
131	ASSERT(item);	131	ASSERT(item);
132	ASSERT((keys > 0) && (keys <= PAGE_HT_KEYS));	132	ASSERT((keys > 0) && (keys <= PAGE_HT_KEYS));
133		133
134	/*	134	/*
135	* Convert item to PTE.	135	* Convert item to PTE.
136	*/	136	*/
137	t = hash_table_get_instance(item, pte_t, link);	137	t = hash_table_get_instance(item, pte_t, link);
138		138
139	if (keys == PAGE_HT_KEYS) {	139	if (keys == PAGE_HT_KEYS) {
140	return (key[KEY_AS] == (uintptr_t) t->as) &&	140	return (key[KEY_AS] == (uintptr_t) t->as) &&
141	(key[KEY_PAGE] == t->page);	141	(key[KEY_PAGE] == t->page);
142	} else {	142	} else {
143	return (key[KEY_AS] == (uintptr_t) t->as);	143	return (key[KEY_AS] == (uintptr_t) t->as);
144	}	144	}
145	}	145	}
146		146
147	/** Callback on page hash table item removal.	147	/** Callback on page hash table item removal.
148	*	148	*
149	* @param item Page hash table item being removed.	149	* @param item Page hash table item being removed.
150	*/	150	*/
151	void remove_callback(link_t *item)	151	void remove_callback(link_t *item)
152	{	152	{
153	pte_t *t;	153	pte_t *t;
154		154
155	ASSERT(item);	155	ASSERT(item);
156		156
157	/*	157	/*
158	* Convert item to PTE.	158	* Convert item to PTE.
159	*/	159	*/
160	t = hash_table_get_instance(item, pte_t, link);	160	t = hash_table_get_instance(item, pte_t, link);
161		161
162	free(t);	162	free(t);
163	}	163	}
164		164
165	/** Map page to frame using page hash table.	165	/** Map page to frame using page hash table.
166	*	166	*
167	* Map virtual address page to physical address frame	167	* Map virtual address page to physical address frame
168	* using flags.	168	* using flags.
169	*	169	*
170	* The page table must be locked and interrupts must be disabled.	170	* The page table must be locked and interrupts must be disabled.
171	*	171	*
172	* @param as Address space to which page belongs.	172	* @param as Address space to which page belongs.
173	* @param page Virtual address of the page to be mapped.	173	* @param page Virtual address of the page to be mapped.
174	* @param frame Physical address of memory frame to which the mapping is done.	174	* @param frame Physical address of memory frame to which the mapping is done.
175	* @param flags Flags to be used for mapping.	175	* @param flags Flags to be used for mapping.
176	*/	176	*/
177	void ht_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame, int flags)	177	void ht_mapping_insert(as_t *as, uintptr_t page, uintptr_t frame, int flags)
178	{	178	{
179	pte_t *t;	179	pte_t *t;
180	unative_t key[2] = {	180	unative_t key[2] = {
181	(uintptr_t) as,	181	(uintptr_t) as,
182	page = ALIGN_DOWN(page, PAGE_SIZE)	182	page = ALIGN_DOWN(page, PAGE_SIZE)
183	};	183	};
184		184
185	if (!hash_table_find(&page_ht, key)) {	185	if (!hash_table_find(&page_ht, key)) {
186	t = (pte_t *) malloc(sizeof(pte_t), FRAME_ATOMIC);	186	t = (pte_t *) malloc(sizeof(pte_t), FRAME_ATOMIC);
187	ASSERT(t != NULL);	187	ASSERT(t != NULL);
188		188
189	t->g = (flags & PAGE_GLOBAL) != 0;	189	t->g = (flags & PAGE_GLOBAL) != 0;
190	t->x = (flags & PAGE_EXEC) != 0;	190	t->x = (flags & PAGE_EXEC) != 0;
191	t->w = (flags & PAGE_WRITE) != 0;	191	t->w = (flags & PAGE_WRITE) != 0;
192	t->k = !(flags & PAGE_USER);	192	t->k = !(flags & PAGE_USER);
193	t->c = (flags & PAGE_CACHEABLE) != 0;	193	t->c = (flags & PAGE_CACHEABLE) != 0;
194	t->p = !(flags & PAGE_NOT_PRESENT);	194	t->p = !(flags & PAGE_NOT_PRESENT);
-		195	t->a = false;
-		196	t->d = false;
195		197
196	t->as = as;	198	t->as = as;
197	t->page = ALIGN_DOWN(page, PAGE_SIZE);	199	t->page = ALIGN_DOWN(page, PAGE_SIZE);
198	t->frame = ALIGN_DOWN(frame, FRAME_SIZE);	200	t->frame = ALIGN_DOWN(frame, FRAME_SIZE);
199		201
200	hash_table_insert(&page_ht, key, &t->link);	202	hash_table_insert(&page_ht, key, &t->link);
201	}	203	}
202	}	204	}
203		205
204	/** Remove mapping of page from page hash table.	206	/** Remove mapping of page from page hash table.
205	*	207	*
206	* Remove any mapping of page within address space as.	208	* Remove any mapping of page within address space as.
207	* TLB shootdown should follow in order to make effects of	209	* TLB shootdown should follow in order to make effects of
208	* this call visible.	210	* this call visible.
209	*	211	*
210	* The page table must be locked and interrupts must be disabled.	212	* The page table must be locked and interrupts must be disabled.
211	*	213	*
212	* @param as Address space to wich page belongs.	214	* @param as Address space to wich page belongs.
213	* @param page Virtual address of the page to be demapped.	215	* @param page Virtual address of the page to be demapped.
214	*/	216	*/
215	void ht_mapping_remove(as_t *as, uintptr_t page)	217	void ht_mapping_remove(as_t *as, uintptr_t page)
216	{	218	{
217	unative_t key[2] = {	219	unative_t key[2] = {
218	(uintptr_t) as,	220	(uintptr_t) as,
219	page = ALIGN_DOWN(page, PAGE_SIZE)	221	page = ALIGN_DOWN(page, PAGE_SIZE)
220	};	222	};
221		223
222	/*	224	/*
223	* Note that removed PTE's will be freed	225	* Note that removed PTE's will be freed
224	* by remove_callback().	226	* by remove_callback().
225	*/	227	*/
226	hash_table_remove(&page_ht, key, 2);	228	hash_table_remove(&page_ht, key, 2);
227	}	229	}
228		230
229		231
230	/** Find mapping for virtual page in page hash table.	232	/** Find mapping for virtual page in page hash table.
231	*	233	*
232	* Find mapping for virtual page.	234	* Find mapping for virtual page.
233	*	235	*
234	* The page table must be locked and interrupts must be disabled.	236	* The page table must be locked and interrupts must be disabled.
235	*	237	*
236	* @param as Address space to wich page belongs.	238	* @param as Address space to wich page belongs.
237	* @param page Virtual page.	239	* @param page Virtual page.
238	*	240	*
239	* @return NULL if there is no such mapping; requested mapping otherwise.	241	* @return NULL if there is no such mapping; requested mapping otherwise.
240	*/	242	*/
241	pte_t ht_mapping_find(as_t as, uintptr_t page)	243	pte_t ht_mapping_find(as_t as, uintptr_t page)
242	{	244	{
243	link_t *hlp;	245	link_t *hlp;
244	pte_t *t = NULL;	246	pte_t *t = NULL;
245	unative_t key[2] = {	247	unative_t key[2] = {
246	(uintptr_t) as,	248	(uintptr_t) as,
247	page = ALIGN_DOWN(page, PAGE_SIZE)	249	page = ALIGN_DOWN(page, PAGE_SIZE)
248	};	250	};
249		251
250	hlp = hash_table_find(&page_ht, key);	252	hlp = hash_table_find(&page_ht, key);
251	if (hlp)	253	if (hlp)
252	t = hash_table_get_instance(hlp, pte_t, link);	254	t = hash_table_get_instance(hlp, pte_t, link);
253		255
254	return t;	256	return t;
255	}	257	}
256		258
257	/** @}	259	/** @}
258	*/	260	*/
259		261