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>
#include <arch/barrier.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, page, start_anon;
    index_t i;
    bool dirty = false;
 
    if (!as_area_check_access(area, access))
        return AS_PF_FAULT;
 
    ASSERT((addr >= ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) &&
        (addr < entry->p_vaddr + entry->p_memsz));
    i = (addr - ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) >> PAGE_WIDTH;
    base = (uintptr_t)
        (((void *) elf) + ALIGN_DOWN(entry->p_offset, PAGE_SIZE));
 
    /* Virtual address of faulting page*/
    page = ALIGN_DOWN(addr, PAGE_SIZE);
 
    /* Virtual address of the end of initialized part of segment */
    start_anon = entry->p_vaddr + entry->p_filesz;
 
    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,
            page - area->base, &leaf);
        if (!frame) {
            unsigned int i;
 
            /*
             * Workaround for valid NULL address.
             */
 
            for (i = 0; i < leaf->keys; i++) {
                if (leaf->key[i] == page) {
                    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, page, 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 (page >= entry->p_vaddr && page + PAGE_SIZE <= start_anon) {
        /*
         * 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 (entry->p_flags & PF_X) {
                smc_coherence_block((void *) PA2KA(frame),
                    FRAME_SIZE);
            }
            dirty = true;
        } else {
            frame = KA2PA(base + i * FRAME_SIZE);
        }  
    } else if (page >= start_anon) {
        /*
         * 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((void *) PA2KA(frame), FRAME_SIZE, 0);
        dirty = true;
    } else {
        size_t pad_lo, pad_hi;
        /*
         * The mixed case.
         *
         * The middle part is backed by the ELF image and
         * the lower and upper parts are anonymous memory.
         * (The segment can be and often is shorter than 1 page).
         */
        if (page < entry->p_vaddr)
            pad_lo = entry->p_vaddr - page;
        else
            pad_lo = 0;
 
        if (start_anon < page + PAGE_SIZE)
            pad_hi = page + PAGE_SIZE - start_anon;
        else
            pad_hi = 0;
 
        frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
        memcpy((void *) (PA2KA(frame) + pad_lo),
            (void *) (base + i * FRAME_SIZE + pad_lo),
            FRAME_SIZE - pad_lo - pad_hi);
        if (entry->p_flags & PF_X) {
            smc_coherence_block((void *) (PA2KA(frame) + pad_lo),
                FRAME_SIZE - pad_lo - pad_hi);
        }
        memsetb((void *) PA2KA(frame), pad_lo, 0);
        memsetb((void *) (PA2KA(frame) + FRAME_SIZE - pad_hi), pad_hi,
            0);
        dirty = true;
    }
 
    if (dirty && area->sh_info) {
        frame_reference_add(ADDR2PFN(frame));
        btree_insert(&area->sh_info->pagemap, page - 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, page, 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, start_anon;
    index_t i;
 
    ASSERT((page >= ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) &&
        (page < entry->p_vaddr + entry->p_memsz));
    i = (page - ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) >> PAGE_WIDTH;
    base = (uintptr_t) (((void *) elf) +
        ALIGN_DOWN(entry->p_offset, FRAME_SIZE));
    start_anon = entry->p_vaddr + entry->p_filesz;
 
    if (page >= entry->p_vaddr && page + PAGE_SIZE <= start_anon) {
        if (entry->p_flags & PF_W) {
            /*
             * Free the frame with the copy of writable segment
             * data.
             */
            frame_free(frame);
        }
    } 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);
    }
}
 
/** 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) {
        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;
           
            /*
             * Skip read-only areas of used space that are backed
             * by the ELF image.
             */
            if (!(area->flags & AS_AREA_WRITE))
                if (base >= entry->p_vaddr &&
                    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 >= entry->p_vaddr &&
                        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);
 
                pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));
                frame_reference_add(pfn);
            }
               
        }
    }
    mutex_unlock(&area->sh_info->lock);
}
 
/** @}
 */
 

Rev 3142	Rev 3143
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 <mm/as.h>	41	#include <mm/as.h>
42	#include <mm/frame.h>	42	#include <mm/frame.h>
43	#include <mm/slab.h>	43	#include <mm/slab.h>
44	#include <mm/page.h>	44	#include <mm/page.h>
45	#include <genarch/mm/page_pt.h>	45	#include <genarch/mm/page_pt.h>
46	#include <genarch/mm/page_ht.h>	46	#include <genarch/mm/page_ht.h>
47	#include <align.h>	47	#include <align.h>
48	#include <memstr.h>	48	#include <memstr.h>
49	#include <macros.h>	49	#include <macros.h>
50	#include <arch.h>	50	#include <arch.h>
51	#include <arch/barrier.h>	51	#include <arch/barrier.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 elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);	57	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);	58	static void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);
59	static void elf_share(as_area_t *area);	59	static void elf_share(as_area_t *area);
60		60
61	mem_backend_t elf_backend = {	61	mem_backend_t elf_backend = {
62	.page_fault = elf_page_fault,	62	.page_fault = elf_page_fault,
63	.frame_free = elf_frame_free,	63	.frame_free = elf_frame_free,
64	.share = elf_share	64	.share = elf_share
65	};	65	};
66		66
67	/** Service a page fault in the ELF backend address space area.	67	/** Service a page fault in the ELF backend 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.	73	* @param access Access mode that caused the fault (i.e.
74	* read/write/exec).	74	* read/write/exec).
75	*	75	*
76	* @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK	76	* @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK
77	* on success (i.e. serviced).	77	* on success (i.e. serviced).
78	*/	78	*/
79	int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)	79	int elf_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access)
80	{	80	{
81	elf_header_t *elf = area->backend_data.elf;	81	elf_header_t *elf = area->backend_data.elf;
82	elf_segment_header_t *entry = area->backend_data.segment;	82	elf_segment_header_t *entry = area->backend_data.segment;
83	btree_node_t *leaf;	83	btree_node_t *leaf;
84	uintptr_t base, frame, page, start_anon;	84	uintptr_t base, frame, page, start_anon;
85	index_t i;	85	index_t i;
86	bool dirty = false;	86	bool dirty = false;
87		87
88	if (!as_area_check_access(area, access))	88	if (!as_area_check_access(area, access))
89	return AS_PF_FAULT;	89	return AS_PF_FAULT;
90		90
91	ASSERT((addr >= ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) &&	91	ASSERT((addr >= ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) &&
92	(addr < entry->p_vaddr + entry->p_memsz));	92	(addr < entry->p_vaddr + entry->p_memsz));
93	i = (addr - ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) >> PAGE_WIDTH;	93	i = (addr - ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) >> PAGE_WIDTH;
94	base = (uintptr_t)	94	base = (uintptr_t)
95	(((void *) elf) + ALIGN_DOWN(entry->p_offset, PAGE_SIZE));	95	(((void *) elf) + ALIGN_DOWN(entry->p_offset, PAGE_SIZE));
96		96
97	/* Virtual address of faulting page*/	97	/* Virtual address of faulting page*/
98	page = ALIGN_DOWN(addr, PAGE_SIZE);	98	page = ALIGN_DOWN(addr, PAGE_SIZE);
99		99
100	/* Virtual address of the end of initialized part of segment */	100	/* Virtual address of the end of initialized part of segment */
101	start_anon = entry->p_vaddr + entry->p_filesz;	101	start_anon = entry->p_vaddr + entry->p_filesz;
102		102
103	if (area->sh_info) {	103	if (area->sh_info) {
104	bool found = false;	104	bool found = false;
105		105
106	/*	106	/*
107	* The address space area is shared.	107	* The address space area is shared.
108	*/	108	*/
109		109
110	mutex_lock(&area->sh_info->lock);	110	mutex_lock(&area->sh_info->lock);
111	frame = (uintptr_t) btree_search(&area->sh_info->pagemap,	111	frame = (uintptr_t) btree_search(&area->sh_info->pagemap,
112	page - area->base, &leaf);	112	page - area->base, &leaf);
113	if (!frame) {	113	if (!frame) {
114	unsigned int i;	114	unsigned int i;
115		115
116	/*	116	/*
117	* Workaround for valid NULL address.	117	* Workaround for valid NULL address.
118	*/	118	*/
119		119
120	for (i = 0; i < leaf->keys; i++) {	120	for (i = 0; i < leaf->keys; i++) {
121	if (leaf->key[i] == page) {	121	if (leaf->key[i] == page) {
122	found = true;	122	found = true;
123	break;	123	break;
124	}	124	}
125	}	125	}
126	}	126	}
127	if (frame \|\| found) {	127	if (frame \|\| found) {
128	frame_reference_add(ADDR2PFN(frame));	128	frame_reference_add(ADDR2PFN(frame));
129	page_mapping_insert(AS, addr, frame,	129	page_mapping_insert(AS, addr, frame,
130	as_area_get_flags(area));	130	as_area_get_flags(area));
131	if (!used_space_insert(area, page, 1))	131	if (!used_space_insert(area, page, 1))
132	panic("Could not insert used space.\n");	132	panic("Could not insert used space.\n");
133	mutex_unlock(&area->sh_info->lock);	133	mutex_unlock(&area->sh_info->lock);
134	return AS_PF_OK;	134	return AS_PF_OK;
135	}	135	}
136	}	136	}
137		137
138	/*	138	/*
139	* The area is either not shared or the pagemap does not contain the	139	* The area is either not shared or the pagemap does not contain the
140	* mapping.	140	* mapping.
141	*/	141	*/
142	if (page >= entry->p_vaddr && page + PAGE_SIZE <= start_anon) {	142	if (page >= entry->p_vaddr && page + PAGE_SIZE <= start_anon) {
143	/*	143	/*
144	* Initialized portion of the segment. The memory is backed	144	* Initialized portion of the segment. The memory is backed
145	* directly by the content of the ELF image. Pages are	145	* directly by the content of the ELF image. Pages are
146	* only copied if the segment is writable so that there	146	* only copied if the segment is writable so that there
147	* can be more instantions of the same memory ELF image	147	* can be more instantions of the same memory ELF image
148	* used at a time. Note that this could be later done	148	* used at a time. Note that this could be later done
149	* as COW.	149	* as COW.
150	*/	150	*/
151	if (entry->p_flags & PF_W) {	151	if (entry->p_flags & PF_W) {
152	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);	152	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
153	memcpy((void *) PA2KA(frame),	153	memcpy((void *) PA2KA(frame),
154	(void ) (base + i FRAME_SIZE), FRAME_SIZE);	154	(void ) (base + i FRAME_SIZE), FRAME_SIZE);
155	if (entry->p_flags & PF_X) {	155	if (entry->p_flags & PF_X) {
156	smc_coherence_block(PA2KA(frame), FRAME_SIZE);	156	smc_coherence_block((void *) PA2KA(frame),
-		157	FRAME_SIZE);
157	}	158	}
158	dirty = true;	159	dirty = true;
159	} else {	160	} else {
160	frame = KA2PA(base + i * FRAME_SIZE);	161	frame = KA2PA(base + i * FRAME_SIZE);
161	}	162	}
162	} else if (page >= start_anon) {	163	} else if (page >= start_anon) {
163	/*	164	/*
164	* This is the uninitialized portion of the segment.	165	* This is the uninitialized portion of the segment.
165	* It is not physically present in the ELF image.	166	* It is not physically present in the ELF image.
166	* To resolve the situation, a frame must be allocated	167	* To resolve the situation, a frame must be allocated
167	* and cleared.	168	* and cleared.
168	*/	169	*/
169	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);	170	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
170	memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);	171	memsetb((void *) PA2KA(frame), FRAME_SIZE, 0);
171	dirty = true;	172	dirty = true;
172	} else {	173	} else {
173	size_t pad_lo, pad_hi;	174	size_t pad_lo, pad_hi;
174	/*	175	/*
175	* The mixed case.	176	* The mixed case.
176	*	177	*
177	* The middle part is backed by the ELF image and	178	* The middle part is backed by the ELF image and
178	* the lower and upper parts are anonymous memory.	179	* the lower and upper parts are anonymous memory.
179	* (The segment can be and often is shorter than 1 page).	180	* (The segment can be and often is shorter than 1 page).
180	*/	181	*/
181	if (page < entry->p_vaddr)	182	if (page < entry->p_vaddr)
182	pad_lo = entry->p_vaddr - page;	183	pad_lo = entry->p_vaddr - page;
183	else	184	else
184	pad_lo = 0;	185	pad_lo = 0;
185		186
186	if (start_anon < page + PAGE_SIZE)	187	if (start_anon < page + PAGE_SIZE)
187	pad_hi = page + PAGE_SIZE - start_anon;	188	pad_hi = page + PAGE_SIZE - start_anon;
188	else	189	else
189	pad_hi = 0;	190	pad_hi = 0;
190		191
191	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);	192	frame = (uintptr_t)frame_alloc(ONE_FRAME, 0);
192	memcpy((void *) (PA2KA(frame) + pad_lo),	193	memcpy((void *) (PA2KA(frame) + pad_lo),
193	(void ) (base + i FRAME_SIZE + pad_lo),	194	(void ) (base + i FRAME_SIZE + pad_lo),
194	FRAME_SIZE - pad_lo - pad_hi);	195	FRAME_SIZE - pad_lo - pad_hi);
195	if (entry->p_flags & PF_X) {	196	if (entry->p_flags & PF_X) {
196	smc_coherence_block(PA2KA(frame) + pad_lo, FRAME_SIZE -	197	smc_coherence_block((void *) (PA2KA(frame) + pad_lo),
197	pad_lo - pad_hi);	198	FRAME_SIZE - pad_lo - pad_hi);
198	}	199	}
199	memsetb((void *) PA2KA(frame), pad_lo, 0);	200	memsetb((void *) PA2KA(frame), pad_lo, 0);
200	memsetb((void *) (PA2KA(frame) + FRAME_SIZE - pad_hi), pad_hi,	201	memsetb((void *) (PA2KA(frame) + FRAME_SIZE - pad_hi), pad_hi,
201	0);	202	0);
202	dirty = true;	203	dirty = true;
203	}	204	}
204		205
205	if (dirty && area->sh_info) {	206	if (dirty && area->sh_info) {
206	frame_reference_add(ADDR2PFN(frame));	207	frame_reference_add(ADDR2PFN(frame));
207	btree_insert(&area->sh_info->pagemap, page - area->base,	208	btree_insert(&area->sh_info->pagemap, page - area->base,
208	(void *) frame, leaf);	209	(void *) frame, leaf);
209	}	210	}
210		211
211	if (area->sh_info)	212	if (area->sh_info)
212	mutex_unlock(&area->sh_info->lock);	213	mutex_unlock(&area->sh_info->lock);
213		214
214	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));	215	page_mapping_insert(AS, addr, frame, as_area_get_flags(area));
215	if (!used_space_insert(area, page, 1))	216	if (!used_space_insert(area, page, 1))
216	panic("Could not insert used space.\n");	217	panic("Could not insert used space.\n");
217		218
218	return AS_PF_OK;	219	return AS_PF_OK;
219	}	220	}
220		221
221	/** Free a frame that is backed by the ELF backend.	222	/** Free a frame that is backed by the ELF backend.
222	*	223	*
223	* The address space area and page tables must be already locked.	224	* The address space area and page tables must be already locked.
224	*	225	*
225	* @param area Pointer to the address space area.	226	* @param area Pointer to the address space area.
226	* @param page Page that is mapped to frame. Must be aligned to	227	* @param page Page that is mapped to frame. Must be aligned to
227	* PAGE_SIZE.	228	* PAGE_SIZE.
228	* @param frame Frame to be released.	229	* @param frame Frame to be released.
229	*	230	*
230	*/	231	*/
231	void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)	232	void elf_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame)
232	{	233	{
233	elf_header_t *elf = area->backend_data.elf;	234	elf_header_t *elf = area->backend_data.elf;
234	elf_segment_header_t *entry = area->backend_data.segment;	235	elf_segment_header_t *entry = area->backend_data.segment;
235	uintptr_t base, start_anon;	236	uintptr_t base, start_anon;
236	index_t i;	237	index_t i;
237		238
238	ASSERT((page >= ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) &&	239	ASSERT((page >= ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) &&
239	(page < entry->p_vaddr + entry->p_memsz));	240	(page < entry->p_vaddr + entry->p_memsz));
240	i = (page - ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) >> PAGE_WIDTH;	241	i = (page - ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE)) >> PAGE_WIDTH;
241	base = (uintptr_t) (((void *) elf) +	242	base = (uintptr_t) (((void *) elf) +
242	ALIGN_DOWN(entry->p_offset, FRAME_SIZE));	243	ALIGN_DOWN(entry->p_offset, FRAME_SIZE));
243	start_anon = entry->p_vaddr + entry->p_filesz;	244	start_anon = entry->p_vaddr + entry->p_filesz;
244		245
245	if (page >= entry->p_vaddr && page + PAGE_SIZE <= start_anon) {	246	if (page >= entry->p_vaddr && page + PAGE_SIZE <= start_anon) {
246	if (entry->p_flags & PF_W) {	247	if (entry->p_flags & PF_W) {
247	/*	248	/*
248	* Free the frame with the copy of writable segment	249	* Free the frame with the copy of writable segment
249	* data.	250	* data.
250	*/	251	*/
251	frame_free(frame);	252	frame_free(frame);
252	}	253	}
253	} else {	254	} else {
254	/*	255	/*
255	* The frame is either anonymous memory or the mixed case (i.e.	256	* The frame is either anonymous memory or the mixed case (i.e.
256	* lower part is backed by the ELF image and the upper is	257	* lower part is backed by the ELF image and the upper is
257	* anonymous). In any case, a frame needs to be freed.	258	* anonymous). In any case, a frame needs to be freed.
258	*/	259	*/
259	frame_free(frame);	260	frame_free(frame);
260	}	261	}
261	}	262	}
262		263
263	/** Share ELF image backed address space area.	264	/** Share ELF image backed address space area.
264	*	265	*
265	* If the area is writable, then all mapped pages are duplicated in the pagemap.	266	* If the area is writable, then all mapped pages are duplicated in the pagemap.
266	* Otherwise only portions of the area that are not backed by the ELF image	267	* Otherwise only portions of the area that are not backed by the ELF image
267	* are put into the pagemap.	268	* are put into the pagemap.
268	*	269	*
269	* The address space and address space area must be locked prior to the call.	270	* The address space and address space area must be locked prior to the call.
270	*	271	*
271	* @param area Address space area.	272	* @param area Address space area.
272	*/	273	*/
273	void elf_share(as_area_t *area)	274	void elf_share(as_area_t *area)
274	{	275	{
275	elf_segment_header_t *entry = area->backend_data.segment;	276	elf_segment_header_t *entry = area->backend_data.segment;
276	link_t *cur;	277	link_t *cur;
277	btree_node_t leaf, node;	278	btree_node_t leaf, node;
278	uintptr_t start_anon = entry->p_vaddr + entry->p_filesz;	279	uintptr_t start_anon = entry->p_vaddr + entry->p_filesz;
279		280
280	/*	281	/*
281	* Find the node in which to start linear search.	282	* Find the node in which to start linear search.
282	*/	283	*/
283	if (area->flags & AS_AREA_WRITE) {	284	if (area->flags & AS_AREA_WRITE) {
284	node = list_get_instance(area->used_space.leaf_head.next,	285	node = list_get_instance(area->used_space.leaf_head.next,
285	btree_node_t, leaf_link);	286	btree_node_t, leaf_link);
286	} else {	287	} else {
287	(void) btree_search(&area->sh_info->pagemap, start_anon, &leaf);	288	(void) btree_search(&area->sh_info->pagemap, start_anon, &leaf);
288	node = btree_leaf_node_left_neighbour(&area->sh_info->pagemap,	289	node = btree_leaf_node_left_neighbour(&area->sh_info->pagemap,
289	leaf);	290	leaf);
290	if (!node)	291	if (!node)
291	node = leaf;	292	node = leaf;
292	}	293	}
293		294
294	/*	295	/*
295	* Copy used anonymous portions of the area to sh_info's page map.	296	* Copy used anonymous portions of the area to sh_info's page map.
296	*/	297	*/
297	mutex_lock(&area->sh_info->lock);	298	mutex_lock(&area->sh_info->lock);
298	for (cur = &node->leaf_link; cur != &area->used_space.leaf_head;	299	for (cur = &node->leaf_link; cur != &area->used_space.leaf_head;
299	cur = cur->next) {	300	cur = cur->next) {
300	unsigned int i;	301	unsigned int i;
301		302
302	node = list_get_instance(cur, btree_node_t, leaf_link);	303	node = list_get_instance(cur, btree_node_t, leaf_link);
303		304
304	for (i = 0; i < node->keys; i++) {	305	for (i = 0; i < node->keys; i++) {
305	uintptr_t base = node->key[i];	306	uintptr_t base = node->key[i];
306	count_t count = (count_t) node->value[i];	307	count_t count = (count_t) node->value[i];
307	unsigned int j;	308	unsigned int j;
308		309
309	/*	310	/*
310	* Skip read-only areas of used space that are backed	311	* Skip read-only areas of used space that are backed
311	* by the ELF image.	312	* by the ELF image.
312	*/	313	*/
313	if (!(area->flags & AS_AREA_WRITE))	314	if (!(area->flags & AS_AREA_WRITE))
314	if (base >= entry->p_vaddr &&	315	if (base >= entry->p_vaddr &&
315	base + count * PAGE_SIZE <= start_anon)	316	base + count * PAGE_SIZE <= start_anon)
316	continue;	317	continue;
317		318
318	for (j = 0; j < count; j++) {	319	for (j = 0; j < count; j++) {
319	pte_t *pte;	320	pte_t *pte;
320		321
321	/*	322	/*
322	* Skip read-only pages that are backed by the	323	* Skip read-only pages that are backed by the
323	* ELF image.	324	* ELF image.
324	*/	325	*/
325	if (!(area->flags & AS_AREA_WRITE))	326	if (!(area->flags & AS_AREA_WRITE))
326	if (base >= entry->p_vaddr &&	327	if (base >= entry->p_vaddr &&
327	base + (j + 1) * PAGE_SIZE <=	328	base + (j + 1) * PAGE_SIZE <=
328	start_anon)	329	start_anon)
329	continue;	330	continue;
330		331
331	page_table_lock(area->as, false);	332	page_table_lock(area->as, false);
332	pte = page_mapping_find(area->as,	333	pte = page_mapping_find(area->as,
333	base + j * PAGE_SIZE);	334	base + j * PAGE_SIZE);
334	ASSERT(pte && PTE_VALID(pte) &&	335	ASSERT(pte && PTE_VALID(pte) &&
335	PTE_PRESENT(pte));	336	PTE_PRESENT(pte));
336	btree_insert(&area->sh_info->pagemap,	337	btree_insert(&area->sh_info->pagemap,
337	(base + j * PAGE_SIZE) - area->base,	338	(base + j * PAGE_SIZE) - area->base,
338	(void *) PTE_GET_FRAME(pte), NULL);	339	(void *) PTE_GET_FRAME(pte), NULL);
339	page_table_unlock(area->as, false);	340	page_table_unlock(area->as, false);
340		341
341	pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));	342	pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));
342	frame_reference_add(pfn);	343	frame_reference_add(pfn);
343	}	344	}
344		345
345	}	346	}
346	}	347	}
347	mutex_unlock(&area->sh_info->lock);	348	mutex_unlock(&area->sh_info->lock);
348	}	349	}
349		350
350	/** @}	351	/** @}
351	*/	352	*/
352		353

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(root)/trunk/kernel/generic/src/mm/backend_elf.c – Rev 3142 → 3143