WebSVN – HelenOS – Diff – /trunk/kernel/generic/src/mm/backend_elf.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 address space areas backed by an ELF image.
 */
 
#include <lib/elf.h>
#include <debug.h>
#include <arch/types.h>
 
#include <mm/as.h>
#include <mm/frame.h>
#include <mm/slab.h>
#include <mm/page.h>
#include <genarch/mm/page_pt.h>
#include <genarch/mm/page_ht.h>
#include <align.h>
#include <memstr.h>
#include <macros.h>
#include <arch.h>
 
#ifdef CONFIG_VIRT_IDX_DCACHE
#include <arch/mm/cache.h>
#endif
 
static int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);
static void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);
static void elf_share(as_area_t *area);
 
mem_backend_t elf_backend = {
    .page_fault = elf_page_fault,
    .frame_free = elf_frame_free,
    .share = elf_share
};
 
/** Service a page fault in the ELF backend 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 elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)
{
    elf_header_t *elf = area->backend_data.elf;
    elf_segment_header_t *entry = area->backend_data.segment;
    btree_node_t *leaf;
    uintptr_t base, frame;
    index_t i;
 
    if (!as_area_check_access(area, access))
        return AS_PF_FAULT;
 
    ASSERT((addr >= entry->p_vaddr) && (addr < entry->p_vaddr + entry->p_memsz));
    i = (addr - entry->p_vaddr) >> PAGE_WIDTH;
    base = (uintptr_t) (((void *) elf) + entry->p_offset);
    ASSERT(ALIGN_UP(base, FRAME_SIZE) == base);
 
    if (area->sh_info) {
        bool found = false;
 
        /*
         * The address space area is shared.
         */
         
        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) {
            int i;
 
            /*
             * Workaround for valid NULL address.
             */
 
            for (i = 0; i < leaf->keys; i++) {
                if (leaf->key[i] == ALIGN_DOWN(addr, PAGE_SIZE)) {
                    found = true;
                    break;
                }
            }
        }
        if (frame || found) {
            frame_reference_add(ADDR2PFN(frame));
            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");
            mutex_unlock(&area->sh_info->lock);
            return AS_PF_OK;
        }
    }
   
    /*
     * The area is either not shared or the pagemap does not contain the mapping.
     */
   
    if (ALIGN_DOWN(addr, PAGE_SIZE) + PAGE_SIZE < entry->p_vaddr + entry->p_filesz) {
        /*
         * Initialized portion of the segment. The memory is backed
         * directly by the content of the ELF image. Pages are
         * only copied if the segment is writable so that there
         * can be more instantions of the same memory ELF image
         * used at a time. Note that this could be later done
         * as COW.
         */
        if (entry->p_flags & PF_W) {
            frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
            memcpy((void *) PA2KA(frame), (void *) (base + i*FRAME_SIZE), FRAME_SIZE);
           
            if (area->sh_info) {
                frame_reference_add(ADDR2PFN(frame));
                btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
                    (void *) frame, leaf);
            }
 
        } else {
            frame = KA2PA(base + i*FRAME_SIZE);
        }  
    } else if (ALIGN_DOWN(addr, PAGE_SIZE) >= ALIGN_UP(entry->p_vaddr + entry->p_filesz, PAGE_SIZE)) {
        /*
         * This is the uninitialized portion of the segment.
         * It is not physically present in the ELF image.
         * To resolve the situation, a frame must be allocated
         * and cleared.
         */
        frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
        memsetb(PA2KA(frame), FRAME_SIZE, 0);
 
        if (area->sh_info) {
            frame_reference_add(ADDR2PFN(frame));
            btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
                (void *) frame, leaf);
        }
 
    } else {
        size_t size;
        /*
         * The mixed case.
         * The lower part is backed by the ELF image and
         * the upper part is anonymous memory.
         */
        size = entry->p_filesz - (i<<PAGE_WIDTH);
        frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
        memsetb(PA2KA(frame) + size, FRAME_SIZE - size, 0);
        memcpy((void *) PA2KA(frame), (void *) (base + i*FRAME_SIZE), size);
 
        if (area->sh_info) {
            frame_reference_add(ADDR2PFN(frame));
            btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
                (void *) frame, leaf);
        }
 
    }
   
    if (area->sh_info)
        mutex_unlock(&area->sh_info->lock);
   
    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 ELF backend.
 *
 * The address space area and page tables must be already locked.
 *
 * @param area Pointer to the address space area.
 * @param page Page that is mapped to frame. Must be aligned to PAGE_SIZE.
 * @param frame Frame to be released.
 *
 */
void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)
{
    elf_header_t *elf = area->backend_data.elf;
    elf_segment_header_t *entry = area->backend_data.segment;
    uintptr_t base;
    index_t i;
   
    ASSERT((page >= entry->p_vaddr) && (page < entry->p_vaddr + entry->p_memsz));
    i = (page - entry->p_vaddr) >> PAGE_WIDTH;
    base = (uintptr_t) (((void *) elf) + entry->p_offset);
    ASSERT(ALIGN_UP(base, FRAME_SIZE) == base);
   
    if (page + PAGE_SIZE < ALIGN_UP(entry->p_vaddr + entry->p_filesz, PAGE_SIZE)) {
        if (entry->p_flags & PF_W) {
            /*
             * Free the frame with the copy of writable segment data.
             */
            frame_free(frame);
#ifdef CONFIG_VIRT_IDX_DCACHE
                dcache_flush_frame(page, frame);
#endif
        }
    } else {
        /*
         * The frame is either anonymous memory or the mixed case (i.e. lower
         * part is backed by the ELF image and the upper is anonymous).
         * In any case, a frame needs to be freed.
         */
        frame_free(frame);
#ifdef CONFIG_VIRT_IDX_DCACHE
            dcache_flush_frame(page, frame);
#endif
    }
}
 
/** Share ELF image backed address space area.
 *
 * If the area is writable, then all mapped pages are duplicated in the pagemap.
 * Otherwise only portions of the area that are not backed by the ELF image
 * are put into the pagemap.
 *
 * The address space and address space area must be locked prior to the call.
 *
 * @param area Address space area.
 */
void elf_share(as_area_t *area)
{
    elf_segment_header_t *entry = area->backend_data.segment;
    link_t *cur;
    btree_node_t *leaf, *node;
    uintptr_t start_anon = entry->p_vaddr + entry->p_filesz;
 
    /*
     * Find the node in which to start linear search.
     */
    if (area->flags & AS_AREA_WRITE) {
        node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);
    } else {
        (void) btree_search(&area->sh_info->pagemap, start_anon, &leaf);
        node = btree_leaf_node_left_neighbour(&area->sh_info->pagemap, leaf);
        if (!node)
            node = leaf;
    }
 
    /*
     * Copy used anonymous portions of the area to sh_info's page map.
     */
    mutex_lock(&area->sh_info->lock);
    for (cur = &node->leaf_link; cur != &area->used_space.leaf_head; cur = cur->next) {
        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];
            int j;
           
            /*
             * Skip read-only areas of used space that are backed
             * by the ELF image.
             */
            if (!(area->flags & AS_AREA_WRITE))
                if (base + count*PAGE_SIZE <= start_anon)
                    continue;
           
            for (j = 0; j < count; j++) {
                pte_t *pte;
           
                /*
                 * Skip read-only pages that are backed by the ELF image.
                 */
                if (!(area->flags & AS_AREA_WRITE))
                    if (base + (j + 1)*PAGE_SIZE <= start_anon)
                        continue;
               
                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);
                frame_reference_add(ADDR2PFN(PTE_GET_FRAME(pte)));
            }
               
        }
    }
    mutex_unlock(&area->sh_info->lock);
}
 
/** @}
 */
 

Subversion Repositories HelenOS

(root)/trunk/kernel/generic/src/mm/backend_elf.c – Rev 2076 → 2089

Rev 2076		Rev 2089
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 address space areas backed by an ELF image.	35	* @brief Backend for address space areas backed by an ELF image.
36	*/	36	*/
37		37
38	#include <lib/elf.h>	38	#include <lib/elf.h>
39	#include <debug.h>	39	#include <debug.h>
40	#include <arch/types.h>	40	#include <arch/types.h>
41	#include <typedefs.h>	-
42	#include <mm/as.h>	41	#include <mm/as.h>
43	#include <mm/frame.h>	42	#include <mm/frame.h>
44	#include <mm/slab.h>	43	#include <mm/slab.h>
45	#include <mm/page.h>	44	#include <mm/page.h>
46	#include <genarch/mm/page_pt.h>	45	#include <genarch/mm/page_pt.h>
47	#include <genarch/mm/page_ht.h>	46	#include <genarch/mm/page_ht.h>
48	#include <align.h>	47	#include <align.h>
49	#include <memstr.h>	48	#include <memstr.h>
50	#include <macros.h>	49	#include <macros.h>
51	#include <arch.h>	50	#include <arch.h>
52		51
53	#ifdef CONFIG_VIRT_IDX_DCACHE	52	#ifdef CONFIG_VIRT_IDX_DCACHE
54	#include <arch/mm/cache.h>	53	#include <arch/mm/cache.h>
55	#endif	54	#endif
56		55
57	static int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);	56	static int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);
58	static void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);	57	static void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);
59	static void elf_share(as_area_t *area);	58	static void elf_share(as_area_t *area);
60		59
61	mem_backend_t elf_backend = {	60	mem_backend_t elf_backend = {
62	.page_fault = elf_page_fault,	61	.page_fault = elf_page_fault,
63	.frame_free = elf_frame_free,	62	.frame_free = elf_frame_free,
64	.share = elf_share	63	.share = elf_share
65	};	64	};
66		65
67	/** Service a page fault in the ELF backend address space area.	66	/** Service a page fault in the ELF backend address space area.
68	*	67	*
69	* The address space area and page tables must be already locked.	68	* The address space area and page tables must be already locked.
70	*	69	*
71	* @param area Pointer to the address space area.	70	* @param area Pointer to the address space area.
72	* @param addr Faulting virtual address.	71	* @param addr Faulting virtual address.
73	* @param access Access mode that caused the fault (i.e. read/write/exec).	72	* @param access Access mode that caused the fault (i.e. read/write/exec).
74	*	73	*
75	* @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK on success (i.e. serviced).	74	* @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK on success (i.e. serviced).
76	*/	75	*/
77	int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)	76	int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)
78	{	77	{
79	elf_header_t *elf = area->backend_data.elf;	78	elf_header_t *elf = area->backend_data.elf;
80	elf_segment_header_t *entry = area->backend_data.segment;	79	elf_segment_header_t *entry = area->backend_data.segment;
81	btree_node_t *leaf;	80	btree_node_t *leaf;
82	uintptr_t base, frame;	81	uintptr_t base, frame;
83	index_t i;	82	index_t i;
84		83
85	if (!as_area_check_access(area, access))	84	if (!as_area_check_access(area, access))
86	return AS_PF_FAULT;	85	return AS_PF_FAULT;
87		86
88	ASSERT((addr >= entry->p_vaddr) && (addr < entry->p_vaddr + entry->p_memsz));	87	ASSERT((addr >= entry->p_vaddr) && (addr < entry->p_vaddr + entry->p_memsz));
89	i = (addr - entry->p_vaddr) >> PAGE_WIDTH;	88	i = (addr - entry->p_vaddr) >> PAGE_WIDTH;
90	base = (uintptr_t) (((void *) elf) + entry->p_offset);	89	base = (uintptr_t) (((void *) elf) + entry->p_offset);
91	ASSERT(ALIGN_UP(base, FRAME_SIZE) == base);	90	ASSERT(ALIGN_UP(base, FRAME_SIZE) == base);
92		91
93	if (area->sh_info) {	92	if (area->sh_info) {
94	bool found = false;	93	bool found = false;
95		94
96	/*	95	/*
97	* The address space area is shared.	96	* The address space area is shared.
98	*/	97	*/
99		98
100	mutex_lock(&area->sh_info->lock);	99	mutex_lock(&area->sh_info->lock);
101	frame = (uintptr_t) btree_search(&area->sh_info->pagemap,	100	frame = (uintptr_t) btree_search(&area->sh_info->pagemap,
102	ALIGN_DOWN(addr, PAGE_SIZE) - area->base, &leaf);	101	ALIGN_DOWN(addr, PAGE_SIZE) - area->base, &leaf);
103	if (!frame) {	102	if (!frame) {
104	int i;	103	int i;
105		104
106	/*	105	/*
107	* Workaround for valid NULL address.	106	* Workaround for valid NULL address.
108	*/	107	*/
109		108
110	for (i = 0; i < leaf->keys; i++) {	109	for (i = 0; i < leaf->keys; i++) {
111	if (leaf->key[i] == ALIGN_DOWN(addr, PAGE_SIZE)) {	110	if (leaf->key[i] == ALIGN_DOWN(addr, PAGE_SIZE)) {
112	found = true;	111	found = true;
113	break;	112	break;
114	}	113	}
115	}	114	}
116	}	115	}
117	if (frame \|\| found) {	116	if (frame \|\| found) {
118	frame_reference_add(ADDR2PFN(frame));	117	frame_reference_add(ADDR2PFN(frame));
119	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));	118	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));
120	if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))	119	if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))
121	panic("Could not insert used space.\n");	120	panic("Could not insert used space.\n");
122	mutex_unlock(&area->sh_info->lock);	121	mutex_unlock(&area->sh_info->lock);
123	return AS_PF_OK;	122	return AS_PF_OK;
124	}	123	}
125	}	124	}
126		125
127	/*	126	/*
128	* The area is either not shared or the pagemap does not contain the mapping.	127	* The area is either not shared or the pagemap does not contain the mapping.
129	*/	128	*/
130		129
131	if (ALIGN_DOWN(addr, PAGE_SIZE) + PAGE_SIZE < entry->p_vaddr + entry->p_filesz) {	130	if (ALIGN_DOWN(addr, PAGE_SIZE) + PAGE_SIZE < entry->p_vaddr + entry->p_filesz) {
132	/*	131	/*
133	* Initialized portion of the segment. The memory is backed	132	* Initialized portion of the segment. The memory is backed
134	* directly by the content of the ELF image. Pages are	133	* directly by the content of the ELF image. Pages are
135	* only copied if the segment is writable so that there	134	* only copied if the segment is writable so that there
136	* can be more instantions of the same memory ELF image	135	* can be more instantions of the same memory ELF image
137	* used at a time. Note that this could be later done	136	* used at a time. Note that this could be later done
138	* as COW.	137	* as COW.
139	*/	138	*/
140	if (entry->p_flags & PF_W) {	139	if (entry->p_flags & PF_W) {
141	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);	140	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
142	memcpy((void ) PA2KA(frame), (void ) (base + i*FRAME_SIZE), FRAME_SIZE);	141	memcpy((void ) PA2KA(frame), (void ) (base + i*FRAME_SIZE), FRAME_SIZE);
143		142
144	if (area->sh_info) {	143	if (area->sh_info) {
145	frame_reference_add(ADDR2PFN(frame));	144	frame_reference_add(ADDR2PFN(frame));
146	btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,	145	btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
147	(void *) frame, leaf);	146	(void *) frame, leaf);
148	}	147	}
149		148
150	} else {	149	} else {
151	frame = KA2PA(base + i*FRAME_SIZE);	150	frame = KA2PA(base + i*FRAME_SIZE);
152	}	151	}
153	} else if (ALIGN_DOWN(addr, PAGE_SIZE) >= ALIGN_UP(entry->p_vaddr + entry->p_filesz, PAGE_SIZE)) {	152	} else if (ALIGN_DOWN(addr, PAGE_SIZE) >= ALIGN_UP(entry->p_vaddr + entry->p_filesz, PAGE_SIZE)) {
154	/*	153	/*
155	* This is the uninitialized portion of the segment.	154	* This is the uninitialized portion of the segment.
156	* It is not physically present in the ELF image.	155	* It is not physically present in the ELF image.
157	* To resolve the situation, a frame must be allocated	156	* To resolve the situation, a frame must be allocated
158	* and cleared.	157	* and cleared.
159	*/	158	*/
160	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);	159	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
161	memsetb(PA2KA(frame), FRAME_SIZE, 0);	160	memsetb(PA2KA(frame), FRAME_SIZE, 0);
162		161
163	if (area->sh_info) {	162	if (area->sh_info) {
164	frame_reference_add(ADDR2PFN(frame));	163	frame_reference_add(ADDR2PFN(frame));
165	btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,	164	btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
166	(void *) frame, leaf);	165	(void *) frame, leaf);
167	}	166	}
168		167
169	} else {	168	} else {
170	size_t size;	169	size_t size;
171	/*	170	/*
172	* The mixed case.	171	* The mixed case.
173	* The lower part is backed by the ELF image and	172	* The lower part is backed by the ELF image and
174	* the upper part is anonymous memory.	173	* the upper part is anonymous memory.
175	*/	174	*/
176	size = entry->p_filesz - (i<<PAGE_WIDTH);	175	size = entry->p_filesz - (i<<PAGE_WIDTH);
177	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);	176	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
178	memsetb(PA2KA(frame) + size, FRAME_SIZE - size, 0);	177	memsetb(PA2KA(frame) + size, FRAME_SIZE - size, 0);
179	memcpy((void ) PA2KA(frame), (void ) (base + i*FRAME_SIZE), size);	178	memcpy((void ) PA2KA(frame), (void ) (base + i*FRAME_SIZE), size);
180		179
181	if (area->sh_info) {	180	if (area->sh_info) {
182	frame_reference_add(ADDR2PFN(frame));	181	frame_reference_add(ADDR2PFN(frame));
183	btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,	182	btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base,
184	(void *) frame, leaf);	183	(void *) frame, leaf);
185	}	184	}
186		185
187	}	186	}
188		187
189	if (area->sh_info)	188	if (area->sh_info)
190	mutex_unlock(&area->sh_info->lock);	189	mutex_unlock(&area->sh_info->lock);
191		190
192	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));	191	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));
193	if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))	192	if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1))
194	panic("Could not insert used space.\n");	193	panic("Could not insert used space.\n");
195		194
196	return AS_PF_OK;	195	return AS_PF_OK;
197	}	196	}
198		197
199	/** Free a frame that is backed by the ELF backend.	198	/** Free a frame that is backed by the ELF backend.
200	*	199	*
201	* The address space area and page tables must be already locked.	200	* The address space area and page tables must be already locked.
202	*	201	*
203	* @param area Pointer to the address space area.	202	* @param area Pointer to the address space area.
204	* @param page Page that is mapped to frame. Must be aligned to PAGE_SIZE.	203	* @param page Page that is mapped to frame. Must be aligned to PAGE_SIZE.
205	* @param frame Frame to be released.	204	* @param frame Frame to be released.
206	*	205	*
207	*/	206	*/
208	void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)	207	void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)
209	{	208	{
210	elf_header_t *elf = area->backend_data.elf;	209	elf_header_t *elf = area->backend_data.elf;
211	elf_segment_header_t *entry = area->backend_data.segment;	210	elf_segment_header_t *entry = area->backend_data.segment;
212	uintptr_t base;	211	uintptr_t base;
213	index_t i;	212	index_t i;
214		213
215	ASSERT((page >= entry->p_vaddr) && (page < entry->p_vaddr + entry->p_memsz));	214	ASSERT((page >= entry->p_vaddr) && (page < entry->p_vaddr + entry->p_memsz));
216	i = (page - entry->p_vaddr) >> PAGE_WIDTH;	215	i = (page - entry->p_vaddr) >> PAGE_WIDTH;
217	base = (uintptr_t) (((void *) elf) + entry->p_offset);	216	base = (uintptr_t) (((void *) elf) + entry->p_offset);
218	ASSERT(ALIGN_UP(base, FRAME_SIZE) == base);	217	ASSERT(ALIGN_UP(base, FRAME_SIZE) == base);
219		218
220	if (page + PAGE_SIZE < ALIGN_UP(entry->p_vaddr + entry->p_filesz, PAGE_SIZE)) {	219	if (page + PAGE_SIZE < ALIGN_UP(entry->p_vaddr + entry->p_filesz, PAGE_SIZE)) {
221	if (entry->p_flags & PF_W) {	220	if (entry->p_flags & PF_W) {
222	/*	221	/*
223	* Free the frame with the copy of writable segment data.	222	* Free the frame with the copy of writable segment data.
224	*/	223	*/
225	frame_free(frame);	224	frame_free(frame);
226	#ifdef CONFIG_VIRT_IDX_DCACHE	225	#ifdef CONFIG_VIRT_IDX_DCACHE
227	dcache_flush_frame(page, frame);	226	dcache_flush_frame(page, frame);
228	#endif	227	#endif
229	}	228	}
230	} else {	229	} else {
231	/*	230	/*
232	* The frame is either anonymous memory or the mixed case (i.e. lower	231	* The frame is either anonymous memory or the mixed case (i.e. lower
233	* part is backed by the ELF image and the upper is anonymous).	232	* part is backed by the ELF image and the upper is anonymous).
234	* In any case, a frame needs to be freed.	233	* In any case, a frame needs to be freed.
235	*/	234	*/
236	frame_free(frame);	235	frame_free(frame);
237	#ifdef CONFIG_VIRT_IDX_DCACHE	236	#ifdef CONFIG_VIRT_IDX_DCACHE
238	dcache_flush_frame(page, frame);	237	dcache_flush_frame(page, frame);
239	#endif	238	#endif
240	}	239	}
241	}	240	}
242		241
243	/** Share ELF image backed address space area.	242	/** Share ELF image backed address space area.
244	*	243	*
245	* If the area is writable, then all mapped pages are duplicated in the pagemap.	244	* If the area is writable, then all mapped pages are duplicated in the pagemap.
246	* Otherwise only portions of the area that are not backed by the ELF image	245	* Otherwise only portions of the area that are not backed by the ELF image
247	* are put into the pagemap.	246	* are put into the pagemap.
248	*	247	*
249	* The address space and address space area must be locked prior to the call.	248	* The address space and address space area must be locked prior to the call.
250	*	249	*
251	* @param area Address space area.	250	* @param area Address space area.
252	*/	251	*/
253	void elf_share(as_area_t *area)	252	void elf_share(as_area_t *area)
254	{	253	{
255	elf_segment_header_t *entry = area->backend_data.segment;	254	elf_segment_header_t *entry = area->backend_data.segment;
256	link_t *cur;	255	link_t *cur;
257	btree_node_t leaf, node;	256	btree_node_t leaf, node;
258	uintptr_t start_anon = entry->p_vaddr + entry->p_filesz;	257	uintptr_t start_anon = entry->p_vaddr + entry->p_filesz;
259		258
260	/*	259	/*
261	* Find the node in which to start linear search.	260	* Find the node in which to start linear search.
262	*/	261	*/
263	if (area->flags & AS_AREA_WRITE) {	262	if (area->flags & AS_AREA_WRITE) {
264	node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);	263	node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);
265	} else {	264	} else {
266	(void) btree_search(&area->sh_info->pagemap, start_anon, &leaf);	265	(void) btree_search(&area->sh_info->pagemap, start_anon, &leaf);
267	node = btree_leaf_node_left_neighbour(&area->sh_info->pagemap, leaf);	266	node = btree_leaf_node_left_neighbour(&area->sh_info->pagemap, leaf);
268	if (!node)	267	if (!node)
269	node = leaf;	268	node = leaf;
270	}	269	}
271		270
272	/*	271	/*
273	* Copy used anonymous portions of the area to sh_info's page map.	272	* Copy used anonymous portions of the area to sh_info's page map.
274	*/	273	*/
275	mutex_lock(&area->sh_info->lock);	274	mutex_lock(&area->sh_info->lock);
276	for (cur = &node->leaf_link; cur != &area->used_space.leaf_head; cur = cur->next) {	275	for (cur = &node->leaf_link; cur != &area->used_space.leaf_head; cur = cur->next) {
277	int i;	276	int i;
278		277
279	node = list_get_instance(cur, btree_node_t, leaf_link);	278	node = list_get_instance(cur, btree_node_t, leaf_link);
280		279
281	for (i = 0; i < node->keys; i++) {	280	for (i = 0; i < node->keys; i++) {
282	uintptr_t base = node->key[i];	281	uintptr_t base = node->key[i];
283	count_t count = (count_t) node->value[i];	282	count_t count = (count_t) node->value[i];
284	int j;	283	int j;
285		284
286	/*	285	/*
287	* Skip read-only areas of used space that are backed	286	* Skip read-only areas of used space that are backed
288	* by the ELF image.	287	* by the ELF image.
289	*/	288	*/
290	if (!(area->flags & AS_AREA_WRITE))	289	if (!(area->flags & AS_AREA_WRITE))
291	if (base + count*PAGE_SIZE <= start_anon)	290	if (base + count*PAGE_SIZE <= start_anon)
292	continue;	291	continue;
293		292
294	for (j = 0; j < count; j++) {	293	for (j = 0; j < count; j++) {
295	pte_t *pte;	294	pte_t *pte;
296		295
297	/*	296	/*
298	* Skip read-only pages that are backed by the ELF image.	297	* Skip read-only pages that are backed by the ELF image.
299	*/	298	*/
300	if (!(area->flags & AS_AREA_WRITE))	299	if (!(area->flags & AS_AREA_WRITE))
301	if (base + (j + 1)*PAGE_SIZE <= start_anon)	300	if (base + (j + 1)*PAGE_SIZE <= start_anon)
302	continue;	301	continue;
303		302
304	page_table_lock(area->as, false);	303	page_table_lock(area->as, false);
305	pte = page_mapping_find(area->as, base + j*PAGE_SIZE);	304	pte = page_mapping_find(area->as, base + j*PAGE_SIZE);
306	ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));	305	ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
307	btree_insert(&area->sh_info->pagemap, (base + j*PAGE_SIZE) - area->base,	306	btree_insert(&area->sh_info->pagemap, (base + j*PAGE_SIZE) - area->base,
308	(void *) PTE_GET_FRAME(pte), NULL);	307	(void *) PTE_GET_FRAME(pte), NULL);
309	page_table_unlock(area->as, false);	308	page_table_unlock(area->as, false);
310	frame_reference_add(ADDR2PFN(PTE_GET_FRAME(pte)));	309	frame_reference_add(ADDR2PFN(PTE_GET_FRAME(pte)));
311	}	310	}
312		311
313	}	312	}
314	}	313	}
315	mutex_unlock(&area->sh_info->lock);	314	mutex_unlock(&area->sh_info->lock);
316	}	315	}
317		316
318	/** @}	317	/** @}
319	*/	318	*/
320		319