WebSVN – HelenOS – Diff – /branches/sparc/kernel/generic/src/mm/backend_anon.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 genericmm
 * @{
 */
 
/**
 * @file
 * @brief   Backend for anonymous memory address space areas.
 *
 */
 
#include <mm/as.h>
#include <mm/page.h>
#include <genarch/mm/page_pt.h>
#include <genarch/mm/page_ht.h>
#include <mm/frame.h>
#include <mm/slab.h>
#include <synch/mutex.h>
#include <adt/list.h>
#include <adt/btree.h>
#include <errno.h>
#include <arch/types.h>
#include <align.h>
#include <arch.h>
 
#ifdef CONFIG_VIRT_IDX_DCACHE
#include <arch/mm/cache.h>
#endif
 
static int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);
static void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);
static void anon_share(as_area_t *area);
 
mem_backend_t anon_backend = {
    .page_fault = anon_page_fault,
    .frame_free = anon_frame_free,
    .share = anon_share
};
 
/** Service a page fault in the anonymous memory address space area.
 *
 * The address space area and page tables must be already locked.
 *
 * @param area Pointer to the address space area.
 * @param addr Faulting virtual address.
 * @param access Access mode that caused the fault (i.e. read/write/exec).
 *
 * @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK on success (i.e.
 *     serviced).
 */
int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)
{
    uintptr_t frame;
 
 
    if (!as_area_check_access(area, access))
        return AS_PF_FAULT;
 
    if (area->sh_info) {
        btree_node_t *leaf;
       
        /*
         * The area is shared, chances are that the mapping can be found
         * in the pagemap of the address space area share info
         * structure.
         * In the case that the pagemap does not contain the respective
         * mapping, a new frame is allocated and the mapping is created.
         */
        mutex_lock(&area->sh_info->lock);
        frame = (uintptr_t) btree_search(&area->sh_info->pagemap,
            ALIGN_DOWN(addr, PAGE_SIZE) - area->base, &leaf);
        if (!frame) {
            bool allocate = true;
            unsigned int i;
           
            /*
             * Zero can be returned as a valid frame address.
             * Just a small workaround.
             */
            for (i = 0; i < leaf->keys; i++) {
                if (leaf->key[i] ==
                    ALIGN_DOWN(addr, PAGE_SIZE) - area->base) {
                    allocate = false;
                    break;
                }
            }
            if (allocate) {
                frame = (uintptr_t) frame_alloc(ONE_FRAME, 0);
                memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);
 
               
                /*
                 * Insert the address of the newly allocated
                 * frame to the pagemap.
                 */
                btree_insert(&area->sh_info->pagemap,
                    ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
                    (void *) frame, leaf);
            }
        }
        frame_reference_add(ADDR2PFN(frame));
        mutex_unlock(&area->sh_info->lock);
    } else {
 
        /*
         * In general, there can be several reasons that
         * can have caused this fault.
         *
         * - non-existent mapping: the area is an anonymous
         *   area (e.g. heap or 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 = (uintptr_t) frame_alloc(ONE_FRAME, 0);
        memsetb((void *) 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, addr, frame, as_area_get_flags(area));
    if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))
        panic("Could not insert used space.\n");
       
    return AS_PF_OK;
}
 
/** Free a frame that is backed by the anonymous memory backend.
 *
 * The address space area and page tables must be already locked.
 *
 * @param area Ignored.
 * @param page Virtual address of the page corresponding to the frame.
 * @param frame Frame to be released.
 */
void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)
{
    frame_free(frame);
}
 
/** Share the anonymous address space area.
 *
 * Sharing of anonymous area is done by duplicating its entire mapping
 * to the pagemap. Page faults will primarily search for frames there.
 *
 * The address space and address space area must be already locked.
 *
 * @param area Address space area to be shared.
 */
void anon_share(as_area_t *area)
{
    link_t *cur;
 
    /*
     * Copy used portions of the area to sh_info's page map.
     */
    mutex_lock(&area->sh_info->lock);
    for (cur = area->used_space.leaf_head.next;
        cur != &area->used_space.leaf_head; cur = cur->next) {
        btree_node_t *node;
        unsigned int i;
       
        node = list_get_instance(cur, btree_node_t, leaf_link);
        for (i = 0; i < node->keys; i++) {
            uintptr_t base = node->key[i];
            count_t count = (count_t) node->value[i];
            unsigned int j;
           
            for (j = 0; j < count; j++) {
                pte_t *pte;
           
                page_table_lock(area->as, false);
                pte = page_mapping_find(area->as,
                    base + j * PAGE_SIZE);
                ASSERT(pte && PTE_VALID(pte) &&
                    PTE_PRESENT(pte));
                btree_insert(&area->sh_info->pagemap,
                    (base + j * PAGE_SIZE) - area->base,
                    (void *) PTE_GET_FRAME(pte), NULL);
                page_table_unlock(area->as, false);
 
                pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));
                frame_reference_add(pfn);
            }
 
        }
    }
    mutex_unlock(&area->sh_info->lock);
}
 
/** @}
 */
 

Subversion Repositories HelenOS

(root)/branches/sparc/kernel/generic/src/mm/backend_anon.c @ 3862 – Rev 3343 → 3397

Rev 3343		Rev 3397
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 genericmm	29	/** @addtogroup genericmm
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file	34	* @file
35	* @brief Backend for anonymous memory address space areas.	35	* @brief Backend for anonymous memory address space areas.
36	*	36	*
37	*/	37	*/
38		38
39	#include <mm/as.h>	39	#include <mm/as.h>
40	#include <mm/page.h>	40	#include <mm/page.h>
41	#include <genarch/mm/page_pt.h>	41	#include <genarch/mm/page_pt.h>
42	#include <genarch/mm/page_ht.h>	42	#include <genarch/mm/page_ht.h>
43	#include <mm/frame.h>	43	#include <mm/frame.h>
44	#include <mm/slab.h>	44	#include <mm/slab.h>
45	#include <synch/mutex.h>	45	#include <synch/mutex.h>
46	#include <adt/list.h>	46	#include <adt/list.h>
47	#include <adt/btree.h>	47	#include <adt/btree.h>
48	#include <errno.h>	48	#include <errno.h>
49	#include <arch/types.h>	49	#include <arch/types.h>
50	#include <align.h>	50	#include <align.h>
51	#include <arch.h>	51	#include <arch.h>
52		52
53	#ifdef CONFIG_VIRT_IDX_DCACHE	53	#ifdef CONFIG_VIRT_IDX_DCACHE
54	#include <arch/mm/cache.h>	54	#include <arch/mm/cache.h>
55	#endif	55	#endif
56		56
57	static int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);	57	static int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);
58	static void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);	58	static void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);
59	static void anon_share(as_area_t *area);	59	static void anon_share(as_area_t *area);
60		60
61	mem_backend_t anon_backend = {	61	mem_backend_t anon_backend = {
62	.page_fault = anon_page_fault,	62	.page_fault = anon_page_fault,
63	.frame_free = anon_frame_free,	63	.frame_free = anon_frame_free,
64	.share = anon_share	64	.share = anon_share
65	};	65	};
66		66
67	/** Service a page fault in the anonymous memory address space area.	67	/** Service a page fault in the anonymous memory address space area.
68	*	68	*
69	* The address space area and page tables must be already locked.	69	* The address space area and page tables must be already locked.
70	*	70	*
71	* @param area Pointer to the address space area.	71	* @param area Pointer to the address space area.
72	* @param addr Faulting virtual address.	72	* @param addr Faulting virtual address.
73	* @param access Access mode that caused the fault (i.e. read/write/exec).	73	* @param access Access mode that caused the fault (i.e. read/write/exec).
74	*	74	*
75	* @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK on success (i.e.	75	* @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK on success (i.e.
76	* serviced).	76	* serviced).
77	*/	77	*/
78	int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)	78	int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)
79	{	79	{
80	uintptr_t frame;	80	uintptr_t frame;
81	bool dirty = false;	-
82		81
83	if (!as_area_check_access(area, access))	82	if (!as_area_check_access(area, access))
84	return AS_PF_FAULT;	83	return AS_PF_FAULT;
85		84
86	if (area->sh_info) {	85	if (area->sh_info) {
87	btree_node_t *leaf;	86	btree_node_t *leaf;
88		87
89	/*	88	/*
90	* The area is shared, chances are that the mapping can be found	89	* The area is shared, chances are that the mapping can be found
91	* in the pagemap of the address space area share info	90	* in the pagemap of the address space area share info
92	* structure.	91	* structure.
93	* In the case that the pagemap does not contain the respective	92	* In the case that the pagemap does not contain the respective
94	* mapping, a new frame is allocated and the mapping is created.	93	* mapping, a new frame is allocated and the mapping is created.
95	*/	94	*/
96	mutex_lock(&area->sh_info->lock);	95	mutex_lock(&area->sh_info->lock);
97	frame = (uintptr_t) btree_search(&area->sh_info->pagemap,	96	frame = (uintptr_t) btree_search(&area->sh_info->pagemap,
98	ALIGN_DOWN(addr, PAGE_SIZE) - area->base, &leaf);	97	ALIGN_DOWN(addr, PAGE_SIZE) - area->base, &leaf);
99	if (!frame) {	98	if (!frame) {
100	bool allocate = true;	99	bool allocate = true;
101	unsigned int i;	100	unsigned int i;
102		101
103	/*	102	/*
104	* Zero can be returned as a valid frame address.	103	* Zero can be returned as a valid frame address.
105	* Just a small workaround.	104	* Just a small workaround.
106	*/	105	*/
107	for (i = 0; i < leaf->keys; i++) {	106	for (i = 0; i < leaf->keys; i++) {
108	if (leaf->key[i] ==	107	if (leaf->key[i] ==
109	ALIGN_DOWN(addr, PAGE_SIZE)) {	108	ALIGN_DOWN(addr, PAGE_SIZE) - area->base) {
110	allocate = false;	109	allocate = false;
111	break;	110	break;
112	}	111	}
113	}	112	}
114	if (allocate) {	113	if (allocate) {
115	frame = (uintptr_t) frame_alloc(ONE_FRAME, 0);	114	frame = (uintptr_t) frame_alloc(ONE_FRAME, 0);
116	memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);	115	memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);
117	dirty = true;	-
118		116
119	/*	117	/*
120	* Insert the address of the newly allocated	118	* Insert the address of the newly allocated
121	* frame to the pagemap.	119	* frame to the pagemap.
122	*/	120	*/
123	btree_insert(&area->sh_info->pagemap,	121	btree_insert(&area->sh_info->pagemap,
124	ALIGN_DOWN(addr, PAGE_SIZE) - area->base,	122	ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
125	(void *) frame, leaf);	123	(void *) frame, leaf);
126	}	124	}
127	}	125	}
128	frame_reference_add(ADDR2PFN(frame));	126	frame_reference_add(ADDR2PFN(frame));
129	mutex_unlock(&area->sh_info->lock);	127	mutex_unlock(&area->sh_info->lock);
130	} else {	128	} else {
131		129
132	/*	130	/*
133	* In general, there can be several reasons that	131	* In general, there can be several reasons that
134	* can have caused this fault.	132	* can have caused this fault.
135	*	133	*
136	* - non-existent mapping: the area is an anonymous	134	* - non-existent mapping: the area is an anonymous
137	* area (e.g. heap or stack) and so far has not been	135	* area (e.g. heap or stack) and so far has not been
138	* allocated a frame for the faulting page	136	* allocated a frame for the faulting page
139	*	137	*
140	* - non-present mapping: another possibility,	138	* - non-present mapping: another possibility,
141	* currently not implemented, would be frame	139	* currently not implemented, would be frame
142	* reuse; when this becomes a possibility,	140	* reuse; when this becomes a possibility,
143	* do not forget to distinguish between	141	* do not forget to distinguish between
144	* the different causes	142	* the different causes
145	*/	143	*/
146	frame = (uintptr_t) frame_alloc(ONE_FRAME, 0);	144	frame = (uintptr_t) frame_alloc(ONE_FRAME, 0);
147	memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);	145	memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);
148	dirty = true;	-
149	}	146	}
150		147
151	/*	148	/*
152	* Map 'page' to 'frame'.	149	* Map 'page' to 'frame'.
153	* Note that TLB shootdown is not attempted as only new information is	150	* Note that TLB shootdown is not attempted as only new information is
154	* being inserted into page tables.	151	* being inserted into page tables.
155	*/	152	*/
156	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));	153	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));
157	if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))	154	if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))
158	panic("Could not insert used space.\n");	155	panic("Could not insert used space.\n");
159		156
160	return AS_PF_OK;	157	return AS_PF_OK;
161	}	158	}
162		159
163	/** Free a frame that is backed by the anonymous memory backend.	160	/** Free a frame that is backed by the anonymous memory backend.
164	*	161	*
165	* The address space area and page tables must be already locked.	162	* The address space area and page tables must be already locked.
166	*	163	*
167	* @param area Ignored.	164	* @param area Ignored.
168	* @param page Virtual address of the page corresponding to the frame.	165	* @param page Virtual address of the page corresponding to the frame.
169	* @param frame Frame to be released.	166	* @param frame Frame to be released.
170	*/	167	*/
171	void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)	168	void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)
172	{	169	{
173	frame_free(frame);	170	frame_free(frame);
174	}	171	}
175		172
176	/** Share the anonymous address space area.	173	/** Share the anonymous address space area.
177	*	174	*
178	* Sharing of anonymous area is done by duplicating its entire mapping	175	* Sharing of anonymous area is done by duplicating its entire mapping
179	* to the pagemap. Page faults will primarily search for frames there.	176	* to the pagemap. Page faults will primarily search for frames there.
180	*	177	*
181	* The address space and address space area must be already locked.	178	* The address space and address space area must be already locked.
182	*	179	*
183	* @param area Address space area to be shared.	180	* @param area Address space area to be shared.
184	*/	181	*/
185	void anon_share(as_area_t *area)	182	void anon_share(as_area_t *area)
186	{	183	{
187	link_t *cur;	184	link_t *cur;
188		185
189	/*	186	/*
190	* Copy used portions of the area to sh_info's page map.	187	* Copy used portions of the area to sh_info's page map.
191	*/	188	*/
192	mutex_lock(&area->sh_info->lock);	189	mutex_lock(&area->sh_info->lock);
193	for (cur = area->used_space.leaf_head.next;	190	for (cur = area->used_space.leaf_head.next;
194	cur != &area->used_space.leaf_head; cur = cur->next) {	191	cur != &area->used_space.leaf_head; cur = cur->next) {
195	btree_node_t *node;	192	btree_node_t *node;
196	unsigned int i;	193	unsigned int i;
197		194
198	node = list_get_instance(cur, btree_node_t, leaf_link);	195	node = list_get_instance(cur, btree_node_t, leaf_link);
199	for (i = 0; i < node->keys; i++) {	196	for (i = 0; i < node->keys; i++) {
200	uintptr_t base = node->key[i];	197	uintptr_t base = node->key[i];
201	count_t count = (count_t) node->value[i];	198	count_t count = (count_t) node->value[i];
202	unsigned int j;	199	unsigned int j;
203		200
204	for (j = 0; j < count; j++) {	201	for (j = 0; j < count; j++) {
205	pte_t *pte;	202	pte_t *pte;
206		203
207	page_table_lock(area->as, false);	204	page_table_lock(area->as, false);
208	pte = page_mapping_find(area->as,	205	pte = page_mapping_find(area->as,
209	base + j * PAGE_SIZE);	206	base + j * PAGE_SIZE);
210	ASSERT(pte && PTE_VALID(pte) &&	207	ASSERT(pte && PTE_VALID(pte) &&
211	PTE_PRESENT(pte));	208	PTE_PRESENT(pte));
212	btree_insert(&area->sh_info->pagemap,	209	btree_insert(&area->sh_info->pagemap,
213	(base + j * PAGE_SIZE) - area->base,	210	(base + j * PAGE_SIZE) - area->base,
214	(void *) PTE_GET_FRAME(pte), NULL);	211	(void *) PTE_GET_FRAME(pte), NULL);
215	page_table_unlock(area->as, false);	212	page_table_unlock(area->as, false);
216		213
217	pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));	214	pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));
218	frame_reference_add(pfn);	215	frame_reference_add(pfn);
219	}	216	}
220		217
221	}	218	}
222	}	219	}
223	mutex_unlock(&area->sh_info->lock);	220	mutex_unlock(&area->sh_info->lock);
224	}	221	}
225		222
226	/** @}	223	/** @}
227	*/	224	*/
228		225