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


/*
 * Copyright (C) 2001-2006 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/*
 * This file contains address space manipulation functions.
 * Roughly speaking, this is a higher-level client of
 * Virtual Address Translation (VAT) subsystem.
 */
 
#include <mm/as.h>
#include <arch/mm/as.h>
#include <mm/page.h>
#include <mm/frame.h>
#include <mm/slab.h>
#include <mm/tlb.h>
#include <arch/mm/page.h>
#include <genarch/mm/page_pt.h>
#include <genarch/mm/page_ht.h>
#include <mm/asid.h>
#include <arch/mm/asid.h>
#include <arch/types.h>
#include <typedefs.h>
#include <synch/spinlock.h>
#include <config.h>
#include <adt/list.h>
#include <adt/btree.h>
#include <panic.h>
#include <arch/asm.h>
#include <debug.h>
#include <memstr.h>
#include <macros.h>
#include <arch.h>
#include <print.h>
 
as_operations_t *as_operations = NULL;
 
/** Address space lock. It protects inactive_as_with_asid_head. */
SPINLOCK_INITIALIZE(as_lock);
 
/**
 * This list contains address spaces that are not active on any
 * processor and that have valid ASID.
 */
LIST_INITIALIZE(inactive_as_with_asid_head);
 
/** Kernel address space. */
as_t *AS_KERNEL = NULL;
 
static int get_area_flags(as_area_t *a);
static as_area_t *find_area_and_lock(as_t *as, __address va);
static bool check_area_conflicts(as_t *as, __address va, size_t size, as_area_t *avoid_area);
 
/** Initialize address space subsystem. */
void as_init(void)
{
    as_arch_init();
    AS_KERNEL = as_create(FLAG_AS_KERNEL);
        if (!AS_KERNEL)
                panic("can't create kernel address space\n");
}
 
/** Create address space.
 *
 * @param flags Flags that influence way in wich the address space is created.
 */
as_t *as_create(int flags)
{
    as_t *as;
 
    as = (as_t *) malloc(sizeof(as_t), 0);
    link_initialize(&as->inactive_as_with_asid_link);
    spinlock_initialize(&as->lock, "as_lock");
    btree_create(&as->as_area_btree);
   
    if (flags & FLAG_AS_KERNEL)
        as->asid = ASID_KERNEL;
    else
        as->asid = ASID_INVALID;
   
    as->refcount = 0;
    as->page_table = page_table_create(flags);
 
    return as;
}
 
/** Free Adress space */
void as_free(as_t *as)
{
    ASSERT(as->refcount == 0);
 
    /* TODO: free as_areas and other resources held by as */
    /* TODO: free page table */
    free(as);
}
 
/** Create address space area of common attributes.
 *
 * The created address space area is added to the target address space.
 *
 * @param as Target address space.
 * @param flags Flags of the area.
 * @param size Size of area.
 * @param base Base address of area.
 *
 * @return Address space area on success or NULL on failure.
 */
as_area_t *as_area_create(as_t *as, int flags, size_t size, __address base)
{
    ipl_t ipl;
    as_area_t *a;
   
    if (base % PAGE_SIZE)
        return NULL;
 
    /* Writeable executable areas are not supported. */
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
        return NULL;
   
    ipl = interrupts_disable();
    spinlock_lock(&as->lock);
   
    if (!check_area_conflicts(as, base, size, NULL)) {
        spinlock_unlock(&as->lock);
        interrupts_restore(ipl);
        return NULL;
    }
   
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
 
    spinlock_initialize(&a->lock, "as_area_lock");
   
    a->flags = flags;
    a->pages = SIZE2FRAMES(size);
    a->base = base;
   
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
 
    spinlock_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return a;
}
 
/** Initialize mapping for one page of address space.
 *
 * This functions maps 'page' to 'frame' according
 * to attributes of the address space area to
 * wich 'page' belongs.
 *
 * @param as Target address space.
 * @param page Virtual page within the area.
 * @param frame Physical frame to which page will be mapped.
 */
void as_set_mapping(as_t *as, __address page, __address frame)
{
    as_area_t *area;
    ipl_t ipl;
   
    ipl = interrupts_disable();
    page_table_lock(as, true);
   
    area = find_area_and_lock(as, page);
    if (!area) {
        panic("page not part of any as_area\n");
    }
 
    page_mapping_insert(as, page, frame, get_area_flags(area));
   
    spinlock_unlock(&area->lock);
    page_table_unlock(as, true);
    interrupts_restore(ipl);
}
 
/** Handle page fault within the current address space.
 *
 * This is the high-level page fault handler.
 * Interrupts are assumed disabled.
 *
 * @param page Faulting page.
 *
 * @return 0 on page fault, 1 on success.
 */
int as_page_fault(__address page)
{
    pte_t *pte;
    as_area_t *area;
    __address frame;
   
    ASSERT(AS);
 
    spinlock_lock(&AS->lock);
    area = find_area_and_lock(AS, page);   
    if (!area) {
        /*
         * No area contained mapping for 'page'.
         * Signal page fault to low-level handler.
         */
        spinlock_unlock(&AS->lock);
        return 0;
    }
 
    page_table_lock(AS, false);
   
    /*
     * To avoid race condition between two page faults
     * on the same address, we need to make sure
     * the mapping has not been already inserted.
     */
    if ((pte = page_mapping_find(AS, page))) {
        if (PTE_PRESENT(pte)) {
            page_table_unlock(AS, false);
            spinlock_unlock(&area->lock);
            spinlock_unlock(&AS->lock);
            return 1;
        }
    }
 
    /*
     * In general, there can be several reasons that
     * can have caused this fault.
     *
     * - non-existent mapping: the area is a scratch
     *   area (e.g. stack) and so far has not been
     *   allocated a frame for the faulting page
     *
     * - non-present mapping: another possibility,
     *   currently not implemented, would be frame
     *   reuse; when this becomes a possibility,
     *   do not forget to distinguish between
     *   the different causes
     */
    frame = PFN2ADDR(frame_alloc(ONE_FRAME, 0));
    memsetb(PA2KA(frame), FRAME_SIZE, 0);
   
    /*
     * Map 'page' to 'frame'.
     * Note that TLB shootdown is not attempted as only new information is being
     * inserted into page tables.
     */
    page_mapping_insert(AS, page, frame, get_area_flags(area));
    page_table_unlock(AS, false);
   
    spinlock_unlock(&area->lock);
    spinlock_unlock(&AS->lock);
    return 1;
}
 
/** Switch address spaces.
 *
 * @param old Old address space or NULL.
 * @param new New address space.
 */
void as_switch(as_t *old, as_t *new)
{
    ipl_t ipl;
    bool needs_asid = false;
   
    ipl = interrupts_disable();
    spinlock_lock(&as_lock);
 
    /*
     * First, take care of the old address space.
     */
    if (old) {
        spinlock_lock(&old->lock);
        ASSERT(old->refcount);
        if((--old->refcount == 0) && (old != AS_KERNEL)) {
            /*
             * The old address space is no longer active on
             * any processor. It can be appended to the
             * list of inactive address spaces with assigned
             * ASID.
             */
             ASSERT(old->asid != ASID_INVALID);
             list_append(&old->inactive_as_with_asid_link, &inactive_as_with_asid_head);
        }
        spinlock_unlock(&old->lock);
    }
 
    /*
     * Second, prepare the new address space.
     */
    spinlock_lock(&new->lock);
    if ((new->refcount++ == 0) && (new != AS_KERNEL)) {
        if (new->asid != ASID_INVALID)
            list_remove(&new->inactive_as_with_asid_link);
        else
            needs_asid = true;  /* defer call to asid_get() until new->lock is released */
    }
    SET_PTL0_ADDRESS(new->page_table);
    spinlock_unlock(&new->lock);
 
    if (needs_asid) {
        /*
         * Allocation of new ASID was deferred
         * until now in order to avoid deadlock.
         */
        asid_t asid;
       
        asid = asid_get();
        spinlock_lock(&new->lock);
        new->asid = asid;
        spinlock_unlock(&new->lock);
    }
    spinlock_unlock(&as_lock);
    interrupts_restore(ipl);
   
    /*
     * Perform architecture-specific steps.
     * (e.g. write ASID to hardware register etc.)
     */
    as_install_arch(new);
   
    AS = new;
}
 
/** Compute flags for virtual address translation subsytem.
 *
 * The address space area must be locked.
 * Interrupts must be disabled.
 *
 * @param a Address space area.
 *
 * @return Flags to be used in page_mapping_insert().
 */
int get_area_flags(as_area_t *a)
{
    int flags;
 
    flags = PAGE_USER | PAGE_PRESENT | PAGE_CACHEABLE;
   
    if (a->flags & AS_AREA_READ)
        flags |= PAGE_READ;
       
    if (a->flags & AS_AREA_WRITE)
        flags |= PAGE_WRITE;
   
    if (a->flags & AS_AREA_EXEC)
        flags |= PAGE_EXEC;
   
    return flags;
}
 
/** Create page table.
 *
 * Depending on architecture, create either address space
 * private or global page table.
 *
 * @param flags Flags saying whether the page table is for kernel address space.
 *
 * @return First entry of the page table.
 */
pte_t *page_table_create(int flags)
{
        ASSERT(as_operations);
        ASSERT(as_operations->page_table_create);
 
        return as_operations->page_table_create(flags);
}
 
/** Lock page table.
 *
 * This function should be called before any page_mapping_insert(),
 * page_mapping_remove() and page_mapping_find().
 *
 * Locking order is such that address space areas must be locked
 * prior to this call. Address space can be locked prior to this
 * call in which case the lock argument is false.
 *
 * @param as Address space.
 * @param as_locked If false, do not attempt to lock as->lock.
 */
void page_table_lock(as_t *as, bool lock)
{
    ASSERT(as_operations);
    ASSERT(as_operations->page_table_lock);
 
    as_operations->page_table_lock(as, lock);
}
 
/** Unlock page table.
 *
 * @param as Address space.
 * @param as_locked If false, do not attempt to unlock as->lock.
 */
void page_table_unlock(as_t *as, bool unlock)
{
    ASSERT(as_operations);
    ASSERT(as_operations->page_table_unlock);
 
    as_operations->page_table_unlock(as, unlock);
}
 
/** Find address space area and change it.
 *
 * @param as Address space.
 * @param address Virtual address belonging to the area to be changed. Must be page-aligned.
 * @param size New size of the virtual memory block starting at address.
 * @param flags Flags influencing the remap operation. Currently unused.
 *
 * @return address on success, (__address) -1 otherwise.
 */
__address as_remap(as_t *as, __address address, size_t size, int flags)
{
    as_area_t *area = NULL;
    ipl_t ipl;
    size_t pages;
   
    ipl = interrupts_disable();
    spinlock_lock(&as->lock);
   
    /*
     * Locate the area.
     */
    area = find_area_and_lock(as, address);
    if (!area) {
        spinlock_unlock(&as->lock);
        interrupts_restore(ipl);
        return (__address) -1;
    }
 
    pages = SIZE2FRAMES((address - area->base) + size);
    if (pages < area->pages) {
        int i;
 
        /*
         * Shrinking the area.
         * No need to check for overlaps.
         */
        for (i = pages; i < area->pages; i++) {
            pte_t *pte;
           
            /*
             * Releasing physical memory.
             * This depends on the fact that the memory was allocated using frame_alloc().
             */
            page_table_lock(as, false);
            pte = page_mapping_find(as, area->base + i*PAGE_SIZE);
            if (pte && PTE_VALID(pte)) {
                __address frame;
 
                ASSERT(PTE_PRESENT(pte));
                frame = PTE_GET_FRAME(pte);
                page_mapping_remove(as, area->base + i*PAGE_SIZE);
                page_table_unlock(as, false);
 
                frame_free(ADDR2PFN(frame));
            } else {
                page_table_unlock(as, false);
            }
        }
        /*
         * Invalidate TLB's.
         */
        tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);
        tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);
        tlb_shootdown_finalize();
    } else {
        /*
         * Growing the area.
         * Check for overlaps with other address space areas.
         */
        if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {
            spinlock_unlock(&area->lock);
            spinlock_unlock(&as->lock);    
            interrupts_restore(ipl);
            return (__address) -1;
        }
    }
 
    area->pages = pages;
   
    spinlock_unlock(&area->lock);
    spinlock_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return address;
}
 
/** Find address space area and lock it.
 *
 * The address space must be locked and interrupts must be disabled.
 *
 * @param as Address space.
 * @param va Virtual address.
 *
 * @return Locked address space area containing va on success or NULL on failure.
 */
as_area_t *find_area_and_lock(as_t *as, __address va)
{
    as_area_t *a;
    btree_node_t *leaf, *lnode;
    int i;
   
    a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf);
    if (a) {
        /* va is the base address of an address space area */
        spinlock_lock(&a->lock);
        return a;
    }
   
    /*
     * Search the leaf node and the righmost record of its left sibling
     * to find out whether this is a miss or va belongs to an address
     * space area found there.
     */
   
    /* First, search the leaf node itself. */
    for (i = 0; i < leaf->keys; i++) {
        a = (as_area_t *) leaf->value[i];
        spinlock_lock(&a->lock);
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
            return a;
        }
        spinlock_unlock(&a->lock);
    }
 
    /*
     * Second, locate the left sibling and test its last record.
     * Because of its position in the B+tree, it must have base < va.
     */
    if ((lnode = btree_node_left_sibling(&as->as_area_btree, leaf))) {
        a = (as_area_t *) lnode->value[lnode->keys - 1];
        spinlock_lock(&a->lock);
        if (va < a->base + a->pages * PAGE_SIZE) {
            return a;
        }
        spinlock_unlock(&a->lock);
    }
 
    return NULL;
}
 
/** Check area conflicts with other areas.
 *
 * The address space must be locked and interrupts must be disabled.
 *
 * @param as Address space.
 * @param va Starting virtual address of the area being tested.
 * @param size Size of the area being tested.
 * @param avoid_area Do not touch this area.
 *
 * @return True if there is no conflict, false otherwise.
 */
bool check_area_conflicts(as_t *as, __address va, size_t size, as_area_t *avoid_area)
{
    as_area_t *a;
    btree_node_t *leaf, *node;
    int i;
   
    /*
     * We don't want any area to have conflicts with NULL page.
     */
    if (overlaps(va, size, NULL, PAGE_SIZE))
        return false;
   
    /*
     * The leaf node is found in O(log n), where n is proportional to
     * the number of address space areas belonging to as.
     * The check for conflicts is then attempted on the rightmost
     * record in the left sibling, the leftmost record in the right
     * sibling and all records in the leaf node itself.
     */
   
    if ((a = (as_area_t *) btree_search(&as->as_area_btree, va, &leaf))) {
        if (a != avoid_area)
            return false;
    }
   
    /* First, check the two border cases. */
    if ((node = btree_node_left_sibling(&as->as_area_btree, leaf))) {
        a = (as_area_t *) node->value[node->keys - 1];
        spinlock_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            spinlock_unlock(&a->lock);
            return false;
        }
        spinlock_unlock(&a->lock);
    }
    if ((node = btree_node_right_sibling(&as->as_area_btree, leaf))) {
        a = (as_area_t *) node->value[0];
        spinlock_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            spinlock_unlock(&a->lock);
            return false;
        }
        spinlock_unlock(&a->lock);
    }
   
    /* Second, check the leaf node. */
    for (i = 0; i < leaf->keys; i++) {
        a = (as_area_t *) leaf->value[i];
   
        if (a == avoid_area)
            continue;
   
        spinlock_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            spinlock_unlock(&a->lock);
            return false;
        }
        spinlock_unlock(&a->lock);
    }
 
    /*
     * So far, the area does not conflict with other areas.
     * Check if it doesn't conflict with kernel address space.
     */  
    if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
        return !overlaps(va, size,
            KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START);
    }
 
    return true;
}
 

Rev 1147	Rev 1148
1	/*	1	/*
2	* Copyright (C) 2001-2006 Jakub Jermar	2	* Copyright (C) 2001-2006 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/*	29	/*
30	* This file contains address space manipulation functions.	30	* This file contains address space manipulation functions.
31	* Roughly speaking, this is a higher-level client of	31	* Roughly speaking, this is a higher-level client of
32	* Virtual Address Translation (VAT) subsystem.	32	* Virtual Address Translation (VAT) subsystem.
33	*/	33	*/
34		34
35	#include <mm/as.h>	35	#include <mm/as.h>
36	#include <arch/mm/as.h>	36	#include <arch/mm/as.h>
37	#include <mm/page.h>	37	#include <mm/page.h>
38	#include <mm/frame.h>	38	#include <mm/frame.h>
39	#include <mm/slab.h>	39	#include <mm/slab.h>
40	#include <mm/tlb.h>	40	#include <mm/tlb.h>
41	#include <arch/mm/page.h>	41	#include <arch/mm/page.h>
42	#include <genarch/mm/page_pt.h>	42	#include <genarch/mm/page_pt.h>
43	#include <genarch/mm/page_ht.h>	43	#include <genarch/mm/page_ht.h>
44	#include <mm/asid.h>	44	#include <mm/asid.h>
45	#include <arch/mm/asid.h>	45	#include <arch/mm/asid.h>
46	#include <arch/types.h>	46	#include <arch/types.h>
47	#include <typedefs.h>	47	#include <typedefs.h>
48	#include <synch/spinlock.h>	48	#include <synch/spinlock.h>
49	#include <config.h>	49	#include <config.h>
50	#include <adt/list.h>	50	#include <adt/list.h>
51	#include <adt/btree.h>	51	#include <adt/btree.h>
52	#include <panic.h>	52	#include <panic.h>
53	#include <arch/asm.h>	53	#include <arch/asm.h>
54	#include <debug.h>	54	#include <debug.h>
55	#include <memstr.h>	55	#include <memstr.h>
56	#include <macros.h>	56	#include <macros.h>
57	#include <arch.h>	57	#include <arch.h>
58	#include <print.h>	58	#include <print.h>
59		59
60	as_operations_t *as_operations = NULL;	60	as_operations_t *as_operations = NULL;
61		61
62	/** Address space lock. It protects inactive_as_with_asid_head. */	62	/** Address space lock. It protects inactive_as_with_asid_head. */
63	SPINLOCK_INITIALIZE(as_lock);	63	SPINLOCK_INITIALIZE(as_lock);
64		64
65	/**	65	/**
66	* This list contains address spaces that are not active on any	66	* This list contains address spaces that are not active on any
67	* processor and that have valid ASID.	67	* processor and that have valid ASID.
68	*/	68	*/
69	LIST_INITIALIZE(inactive_as_with_asid_head);	69	LIST_INITIALIZE(inactive_as_with_asid_head);
70		70
71	/** Kernel address space. */	71	/** Kernel address space. */
72	as_t *AS_KERNEL = NULL;	72	as_t *AS_KERNEL = NULL;
73		73
74	static int get_area_flags(as_area_t *a);	74	static int get_area_flags(as_area_t *a);
75	static as_area_t find_area_and_lock(as_t as, __address va);	75	static as_area_t find_area_and_lock(as_t as, __address va);
76	static bool check_area_conflicts(as_t as, __address va, size_t size, as_area_t avoid_area);	76	static bool check_area_conflicts(as_t as, __address va, size_t size, as_area_t avoid_area);
77		77
78	/** Initialize address space subsystem. */	78	/** Initialize address space subsystem. */
79	void as_init(void)	79	void as_init(void)
80	{	80	{
81	as_arch_init();	81	as_arch_init();
82	AS_KERNEL = as_create(FLAG_AS_KERNEL);	82	AS_KERNEL = as_create(FLAG_AS_KERNEL);
83	if (!AS_KERNEL)	83	if (!AS_KERNEL)
84	panic("can't create kernel address space\n");	84	panic("can't create kernel address space\n");
85	}	85	}
86		86
87	/** Create address space.	87	/** Create address space.
88	*	88	*
89	* @param flags Flags that influence way in wich the address space is created.	89	* @param flags Flags that influence way in wich the address space is created.
90	*/	90	*/
91	as_t *as_create(int flags)	91	as_t *as_create(int flags)
92	{	92	{
93	as_t *as;	93	as_t *as;
94		94
95	as = (as_t *) malloc(sizeof(as_t), 0);	95	as = (as_t *) malloc(sizeof(as_t), 0);
96	link_initialize(&as->inactive_as_with_asid_link);	96	link_initialize(&as->inactive_as_with_asid_link);
97	spinlock_initialize(&as->lock, "as_lock");	97	spinlock_initialize(&as->lock, "as_lock");
98	btree_create(&as->as_area_btree);	98	btree_create(&as->as_area_btree);
99		99
100	if (flags & FLAG_AS_KERNEL)	100	if (flags & FLAG_AS_KERNEL)
101	as->asid = ASID_KERNEL;	101	as->asid = ASID_KERNEL;
102	else	102	else
103	as->asid = ASID_INVALID;	103	as->asid = ASID_INVALID;
104		104
105	as->refcount = 0;	105	as->refcount = 0;
106	as->page_table = page_table_create(flags);	106	as->page_table = page_table_create(flags);
107		107
108	return as;	108	return as;
109	}	109	}
110		110
111	/** Free Adress space */	111	/** Free Adress space */
112	void as_free(as_t *as)	112	void as_free(as_t *as)
113	{	113	{
114	ASSERT(as->refcount == 0);	114	ASSERT(as->refcount == 0);
115		115
116	/* TODO: free as_areas and other resources held by as */	116	/* TODO: free as_areas and other resources held by as */
117	/* TODO: free page table */	117	/* TODO: free page table */
118	free(as);	118	free(as);
119	}	119	}
120		120
121	/** Create address space area of common attributes.	121	/** Create address space area of common attributes.
122	*	122	*
123	* The created address space area is added to the target address space.	123	* The created address space area is added to the target address space.
124	*	124	*
125	* @param as Target address space.	125	* @param as Target address space.
126	* @param flags Flags of the area.	126	* @param flags Flags of the area.
127	* @param size Size of area.	127	* @param size Size of area.
128	* @param base Base address of area.	128	* @param base Base address of area.
129	*	129	*
130	* @return Address space area on success or NULL on failure.	130	* @return Address space area on success or NULL on failure.
131	*/	131	*/
132	as_area_t as_area_create(as_t as, int flags, size_t size, __address base)	132	as_area_t as_area_create(as_t as, int flags, size_t size, __address base)
133	{	133	{
134	ipl_t ipl;	134	ipl_t ipl;
135	as_area_t *a;	135	as_area_t *a;
136		136
137	if (base % PAGE_SIZE)	137	if (base % PAGE_SIZE)
138	return NULL;	138	return NULL;
139		139
140	/* Writeable executable areas are not supported. */	140	/* Writeable executable areas are not supported. */
141	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))	141	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
142	return NULL;	142	return NULL;
143		143
144	ipl = interrupts_disable();	144	ipl = interrupts_disable();
145	spinlock_lock(&as->lock);	145	spinlock_lock(&as->lock);
146		146
147	if (!check_area_conflicts(as, base, size, NULL)) {	147	if (!check_area_conflicts(as, base, size, NULL)) {
148	spinlock_unlock(&as->lock);	148	spinlock_unlock(&as->lock);
149	interrupts_restore(ipl);	149	interrupts_restore(ipl);
150	return NULL;	150	return NULL;
151	}	151	}
152		152
153	a = (as_area_t *) malloc(sizeof(as_area_t), 0);	153	a = (as_area_t *) malloc(sizeof(as_area_t), 0);
154		154
155	spinlock_initialize(&a->lock, "as_area_lock");	155	spinlock_initialize(&a->lock, "as_area_lock");
156		156
157	a->flags = flags;	157	a->flags = flags;
158	a->pages = SIZE2FRAMES(size);	158	a->pages = SIZE2FRAMES(size);
159	a->base = base;	159	a->base = base;
160		160
161	btree_insert(&as->as_area_btree, base, (void *) a, NULL);	161	btree_insert(&as->as_area_btree, base, (void *) a, NULL);
162		162
163	spinlock_unlock(&as->lock);	163	spinlock_unlock(&as->lock);
164	interrupts_restore(ipl);	164	interrupts_restore(ipl);
165		165
166	return a;	166	return a;
167	}	167	}
168		168
169	/** Initialize mapping for one page of address space.	169	/** Initialize mapping for one page of address space.
170	*	170	*
171	* This functions maps 'page' to 'frame' according	171	* This functions maps 'page' to 'frame' according
172	* to attributes of the address space area to	172	* to attributes of the address space area to
173	* wich 'page' belongs.	173	* wich 'page' belongs.
174	*	174	*
175	* @param as Target address space.	175	* @param as Target address space.
176	* @param page Virtual page within the area.	176	* @param page Virtual page within the area.
177	* @param frame Physical frame to which page will be mapped.	177	* @param frame Physical frame to which page will be mapped.
178	*/	178	*/
179	void as_set_mapping(as_t *as, __address page, __address frame)	179	void as_set_mapping(as_t *as, __address page, __address frame)
180	{	180	{
181	as_area_t *area;	181	as_area_t *area;
182	ipl_t ipl;	182	ipl_t ipl;
183		183
184	ipl = interrupts_disable();	184	ipl = interrupts_disable();
185	page_table_lock(as, true);	185	page_table_lock(as, true);
186		186
187	area = find_area_and_lock(as, page);	187	area = find_area_and_lock(as, page);
188	if (!area) {	188	if (!area) {
189	panic("page not part of any as_area\n");	189	panic("page not part of any as_area\n");
190	}	190	}
191		191
192	page_mapping_insert(as, page, frame, get_area_flags(area));	192	page_mapping_insert(as, page, frame, get_area_flags(area));
193		193
194	spinlock_unlock(&area->lock);	194	spinlock_unlock(&area->lock);
195	page_table_unlock(as, true);	195	page_table_unlock(as, true);
196	interrupts_restore(ipl);	196	interrupts_restore(ipl);
197	}	197	}
198		198
199	/** Handle page fault within the current address space.	199	/** Handle page fault within the current address space.
200	*	200	*
201	* This is the high-level page fault handler.	201	* This is the high-level page fault handler.
202	* Interrupts are assumed disabled.	202	* Interrupts are assumed disabled.
203	*	203	*
204	* @param page Faulting page.	204	* @param page Faulting page.
205	*	205	*
206	* @return 0 on page fault, 1 on success.	206	* @return 0 on page fault, 1 on success.
207	*/	207	*/
208	int as_page_fault(__address page)	208	int as_page_fault(__address page)
209	{	209	{
210	pte_t *pte;	210	pte_t *pte;
211	as_area_t *area;	211	as_area_t *area;
212	__address frame;	212	__address frame;
213		213
214	ASSERT(AS);	214	ASSERT(AS);
215		215
216	spinlock_lock(&AS->lock);	216	spinlock_lock(&AS->lock);
217	area = find_area_and_lock(AS, page);	217	area = find_area_and_lock(AS, page);
218	if (!area) {	218	if (!area) {
219	/*	219	/*
220	* No area contained mapping for 'page'.	220	* No area contained mapping for 'page'.
221	* Signal page fault to low-level handler.	221	* Signal page fault to low-level handler.
222	*/	222	*/
223	spinlock_unlock(&AS->lock);	223	spinlock_unlock(&AS->lock);
224	return 0;	224	return 0;
225	}	225	}
226		226
227	page_table_lock(AS, false);	227	page_table_lock(AS, false);
228		228
229	/*	229	/*
230	* To avoid race condition between two page faults	230	* To avoid race condition between two page faults
231	* on the same address, we need to make sure	231	* on the same address, we need to make sure
232	* the mapping has not been already inserted.	232	* the mapping has not been already inserted.
233	*/	233	*/
234	if ((pte = page_mapping_find(AS, page))) {	234	if ((pte = page_mapping_find(AS, page))) {
235	if (PTE_PRESENT(pte)) {	235	if (PTE_PRESENT(pte)) {
236	page_table_unlock(AS, false);	236	page_table_unlock(AS, false);
237	spinlock_unlock(&area->lock);	237	spinlock_unlock(&area->lock);
238	spinlock_unlock(&AS->lock);	238	spinlock_unlock(&AS->lock);
239	return 1;	239	return 1;
240	}	240	}
241	}	241	}
242		242
243	/*	243	/*
244	* In general, there can be several reasons that	244	* In general, there can be several reasons that
245	* can have caused this fault.	245	* can have caused this fault.
246	*	246	*
247	* - non-existent mapping: the area is a scratch	247	* - non-existent mapping: the area is a scratch
248	* area (e.g. stack) and so far has not been	248	* area (e.g. stack) and so far has not been
249	* allocated a frame for the faulting page	249	* allocated a frame for the faulting page
250	*	250	*
251	* - non-present mapping: another possibility,	251	* - non-present mapping: another possibility,
252	* currently not implemented, would be frame	252	* currently not implemented, would be frame
253	* reuse; when this becomes a possibility,	253	* reuse; when this becomes a possibility,
254	* do not forget to distinguish between	254	* do not forget to distinguish between
255	* the different causes	255	* the different causes
256	*/	256	*/
257	frame = PFN2ADDR(frame_alloc(ONE_FRAME, 0));	257	frame = PFN2ADDR(frame_alloc(ONE_FRAME, 0));
258	memsetb(PA2KA(frame), FRAME_SIZE, 0);	258	memsetb(PA2KA(frame), FRAME_SIZE, 0);
259		259
260	/*	260	/*
261	* Map 'page' to 'frame'.	261	* Map 'page' to 'frame'.
262	* Note that TLB shootdown is not attempted as only new information is being	262	* Note that TLB shootdown is not attempted as only new information is being
263	* inserted into page tables.	263	* inserted into page tables.
264	*/	264	*/
265	page_mapping_insert(AS, page, frame, get_area_flags(area));	265	page_mapping_insert(AS, page, frame, get_area_flags(area));
266	page_table_unlock(AS, false);	266	page_table_unlock(AS, false);
267		267
268	spinlock_unlock(&area->lock);	268	spinlock_unlock(&area->lock);
269	spinlock_unlock(&AS->lock);	269	spinlock_unlock(&AS->lock);
270	return 1;	270	return 1;
271	}	271	}
272		272
273	/** Switch address spaces.	273	/** Switch address spaces.
274	*	274	*
275	* @param old Old address space or NULL.	275	* @param old Old address space or NULL.
276	* @param new New address space.	276	* @param new New address space.
277	*/	277	*/
278	void as_switch(as_t old, as_t new)	278	void as_switch(as_t old, as_t new)
279	{	279	{
280	ipl_t ipl;	280	ipl_t ipl;
281	bool needs_asid = false;	281	bool needs_asid = false;
282		282
283	ipl = interrupts_disable();	283	ipl = interrupts_disable();
284	spinlock_lock(&as_lock);	284	spinlock_lock(&as_lock);
285		285
286	/*	286	/*
287	* First, take care of the old address space.	287	* First, take care of the old address space.
288	*/	288	*/
289	if (old) {	289	if (old) {
290	spinlock_lock(&old->lock);	290	spinlock_lock(&old->lock);
291	ASSERT(old->refcount);	291	ASSERT(old->refcount);
292	if((--old->refcount == 0) && (old != AS_KERNEL)) {	292	if((--old->refcount == 0) && (old != AS_KERNEL)) {
293	/*	293	/*
294	* The old address space is no longer active on	294	* The old address space is no longer active on
295	* any processor. It can be appended to the	295	* any processor. It can be appended to the
296	* list of inactive address spaces with assigned	296	* list of inactive address spaces with assigned
297	* ASID.	297	* ASID.
298	*/	298	*/
299	ASSERT(old->asid != ASID_INVALID);	299	ASSERT(old->asid != ASID_INVALID);
300	list_append(&old->inactive_as_with_asid_link, &inactive_as_with_asid_head);	300	list_append(&old->inactive_as_with_asid_link, &inactive_as_with_asid_head);
301	}	301	}
302	spinlock_unlock(&old->lock);	302	spinlock_unlock(&old->lock);
303	}	303	}
304		304
305	/*	305	/*
306	* Second, prepare the new address space.	306	* Second, prepare the new address space.
307	*/	307	*/
308	spinlock_lock(&new->lock);	308	spinlock_lock(&new->lock);
309	if ((new->refcount++ == 0) && (new != AS_KERNEL)) {	309	if ((new->refcount++ == 0) && (new != AS_KERNEL)) {
310	if (new->asid != ASID_INVALID)	310	if (new->asid != ASID_INVALID)
311	list_remove(&new->inactive_as_with_asid_link);	311	list_remove(&new->inactive_as_with_asid_link);
312	else	312	else
313	needs_asid = true; /* defer call to asid_get() until new->lock is released */	313	needs_asid = true; /* defer call to asid_get() until new->lock is released */
314	}	314	}
315	SET_PTL0_ADDRESS(new->page_table);	315	SET_PTL0_ADDRESS(new->page_table);
316	spinlock_unlock(&new->lock);	316	spinlock_unlock(&new->lock);
317		317
318	if (needs_asid) {	318	if (needs_asid) {
319	/*	319	/*
320	* Allocation of new ASID was deferred	320	* Allocation of new ASID was deferred
321	* until now in order to avoid deadlock.	321	* until now in order to avoid deadlock.
322	*/	322	*/
323	asid_t asid;	323	asid_t asid;
324		324
325	asid = asid_get();	325	asid = asid_get();
326	spinlock_lock(&new->lock);	326	spinlock_lock(&new->lock);
327	new->asid = asid;	327	new->asid = asid;
328	spinlock_unlock(&new->lock);	328	spinlock_unlock(&new->lock);
329	}	329	}
330	spinlock_unlock(&as_lock);	330	spinlock_unlock(&as_lock);
331	interrupts_restore(ipl);	331	interrupts_restore(ipl);
332		332
333	/*	333	/*
334	* Perform architecture-specific steps.	334	* Perform architecture-specific steps.
335	* (e.g. write ASID to hardware register etc.)	335	* (e.g. write ASID to hardware register etc.)
336	*/	336	*/
337	as_install_arch(new);	337	as_install_arch(new);
338		338
339	AS = new;	339	AS = new;
340	}	340	}
341		341
342	/** Compute flags for virtual address translation subsytem.	342	/** Compute flags for virtual address translation subsytem.
343	*	343	*
344	* The address space area must be locked.	344	* The address space area must be locked.
345	* Interrupts must be disabled.	345	* Interrupts must be disabled.
346	*	346	*
347	* @param a Address space area.	347	* @param a Address space area.
348	*	348	*
349	* @return Flags to be used in page_mapping_insert().	349	* @return Flags to be used in page_mapping_insert().
350	*/	350	*/
351	int get_area_flags(as_area_t *a)	351	int get_area_flags(as_area_t *a)
352	{	352	{
353	int flags;	353	int flags;
354		354
355	flags = PAGE_USER \| PAGE_PRESENT \| PAGE_CACHEABLE;	355	flags = PAGE_USER \| PAGE_PRESENT \| PAGE_CACHEABLE;
356		356
357	if (a->flags & AS_AREA_READ)	357	if (a->flags & AS_AREA_READ)
358	flags \|= PAGE_READ;	358	flags \|= PAGE_READ;
359		359
360	if (a->flags & AS_AREA_WRITE)	360	if (a->flags & AS_AREA_WRITE)
361	flags \|= PAGE_WRITE;	361	flags \|= PAGE_WRITE;
362		362
363	if (a->flags & AS_AREA_EXEC)	363	if (a->flags & AS_AREA_EXEC)
364	flags \|= PAGE_EXEC;	364	flags \|= PAGE_EXEC;
365		365
366	return flags;	366	return flags;
367	}	367	}
368		368
369	/** Create page table.	369	/** Create page table.
370	*	370	*
371	* Depending on architecture, create either address space	371	* Depending on architecture, create either address space
372	* private or global page table.	372	* private or global page table.
373	*	373	*
374	* @param flags Flags saying whether the page table is for kernel address space.	374	* @param flags Flags saying whether the page table is for kernel address space.
375	*	375	*
376	* @return First entry of the page table.	376	* @return First entry of the page table.
377	*/	377	*/
378	pte_t *page_table_create(int flags)	378	pte_t *page_table_create(int flags)
379	{	379	{
380	ASSERT(as_operations);	380	ASSERT(as_operations);
381	ASSERT(as_operations->page_table_create);	381	ASSERT(as_operations->page_table_create);
382		382
383	return as_operations->page_table_create(flags);	383	return as_operations->page_table_create(flags);
384	}	384	}
385		385
386	/** Lock page table.	386	/** Lock page table.
387	*	387	*
388	* This function should be called before any page_mapping_insert(),	388	* This function should be called before any page_mapping_insert(),
389	* page_mapping_remove() and page_mapping_find().	389	* page_mapping_remove() and page_mapping_find().
390	*	390	*
391	* Locking order is such that address space areas must be locked	391	* Locking order is such that address space areas must be locked
392	* prior to this call. Address space can be locked prior to this	392	* prior to this call. Address space can be locked prior to this
393	* call in which case the lock argument is false.	393	* call in which case the lock argument is false.
394	*	394	*
395	* @param as Address space.	395	* @param as Address space.
396	* @param as_locked If false, do not attempt to lock as->lock.	396	* @param as_locked If false, do not attempt to lock as->lock.
397	*/	397	*/
398	void page_table_lock(as_t *as, bool lock)	398	void page_table_lock(as_t *as, bool lock)
399	{	399	{
400	ASSERT(as_operations);	400	ASSERT(as_operations);
401	ASSERT(as_operations->page_table_lock);	401	ASSERT(as_operations->page_table_lock);
402		402
403	as_operations->page_table_lock(as, lock);	403	as_operations->page_table_lock(as, lock);
404	}	404	}
405		405
406	/** Unlock page table.	406	/** Unlock page table.
407	*	407	*
408	* @param as Address space.	408	* @param as Address space.
409	* @param as_locked If false, do not attempt to unlock as->lock.	409	* @param as_locked If false, do not attempt to unlock as->lock.
410	*/	410	*/
411	void page_table_unlock(as_t *as, bool unlock)	411	void page_table_unlock(as_t *as, bool unlock)
412	{	412	{
413	ASSERT(as_operations);	413	ASSERT(as_operations);
414	ASSERT(as_operations->page_table_unlock);	414	ASSERT(as_operations->page_table_unlock);
415		415
416	as_operations->page_table_unlock(as, unlock);	416	as_operations->page_table_unlock(as, unlock);
417	}	417	}
418		418
419	/** Find address space area and change it.	419	/** Find address space area and change it.
420	*	420	*
421	* @param as Address space.	421	* @param as Address space.
422	* @param address Virtual address belonging to the area to be changed. Must be page-aligned.	422	* @param address Virtual address belonging to the area to be changed. Must be page-aligned.
423	* @param size New size of the virtual memory block starting at address.	423	* @param size New size of the virtual memory block starting at address.
424	* @param flags Flags influencing the remap operation. Currently unused.	424	* @param flags Flags influencing the remap operation. Currently unused.
425	*	425	*
426	* @return address on success, (__address) -1 otherwise.	426	* @return address on success, (__address) -1 otherwise.
427	*/	427	*/
428	__address as_remap(as_t *as, __address address, size_t size, int flags)	428	__address as_remap(as_t *as, __address address, size_t size, int flags)
429	{	429	{
430	as_area_t *area = NULL;	430	as_area_t *area = NULL;
431	ipl_t ipl;	431	ipl_t ipl;
432	size_t pages;	432	size_t pages;
433		433
434	ipl = interrupts_disable();	434	ipl = interrupts_disable();
435	spinlock_lock(&as->lock);	435	spinlock_lock(&as->lock);
436		436
437	/*	437	/*
438	* Locate the area.	438	* Locate the area.
439	*/	439	*/
440	area = find_area_and_lock(as, address);	440	area = find_area_and_lock(as, address);
441	if (!area) {	441	if (!area) {
442	spinlock_unlock(&as->lock);	442	spinlock_unlock(&as->lock);
443	interrupts_restore(ipl);	443	interrupts_restore(ipl);
444	return (__address) -1;	444	return (__address) -1;
445	}	445	}
446		446
447	pages = SIZE2FRAMES((address - area->base) + size);	447	pages = SIZE2FRAMES((address - area->base) + size);
448	if (pages < area->pages) {	448	if (pages < area->pages) {
449	int i;	449	int i;
450		450
451	/*	451	/*
452	* Shrinking the area.	452	* Shrinking the area.
453	* No need to check for overlaps.	453	* No need to check for overlaps.
454	*/	454	*/
455	for (i = pages; i < area->pages; i++) {	455	for (i = pages; i < area->pages; i++) {
456	pte_t *pte;	456	pte_t *pte;
457		457
458	/*	458	/*
459	* Releasing physical memory.	459	* Releasing physical memory.
460	* This depends on the fact that the memory was allocated using frame_alloc().	460	* This depends on the fact that the memory was allocated using frame_alloc().
461	*/	461	*/
462	page_table_lock(as, false);	462	page_table_lock(as, false);
463	pte = page_mapping_find(as, area->base + i*PAGE_SIZE);	463	pte = page_mapping_find(as, area->base + i*PAGE_SIZE);
464	if (pte && PTE_VALID(pte)) {	464	if (pte && PTE_VALID(pte)) {
465	__address frame;	465	__address frame;
466		466
467	ASSERT(PTE_PRESENT(pte));	467	ASSERT(PTE_PRESENT(pte));
468	frame = PTE_GET_FRAME(pte);	468	frame = PTE_GET_FRAME(pte);
469	page_mapping_remove(as, area->base + i*PAGE_SIZE);	469	page_mapping_remove(as, area->base + i*PAGE_SIZE);
470	page_table_unlock(as, false);	470	page_table_unlock(as, false);
471		471
472	frame_free(ADDR2PFN(frame));	472	frame_free(ADDR2PFN(frame));
473	} else {	473	} else {
474	page_table_unlock(as, false);	474	page_table_unlock(as, false);
475	}	475	}
476	}	476	}
477	/*	477	/*
478	* Invalidate TLB's.	478	* Invalidate TLB's.
479	*/	479	*/
480	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);	480	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);
481	tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);	481	tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);
482	tlb_shootdown_finalize();	482	tlb_shootdown_finalize();
483	} else {	483	} else {
484	/*	484	/*
485	* Growing the area.	485	* Growing the area.
486	* Check for overlaps with other address space areas.	486	* Check for overlaps with other address space areas.
487	*/	487	*/
488	if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {	488	if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {
489	spinlock_unlock(&area->lock);	489	spinlock_unlock(&area->lock);
490	spinlock_unlock(&as->lock);	490	spinlock_unlock(&as->lock);
491	interrupts_restore(ipl);	491	interrupts_restore(ipl);
492	return (__address) -1;	492	return (__address) -1;
493	}	493	}
494	}	494	}
495		495
496	area->pages = pages;	496	area->pages = pages;
497		497
498	spinlock_unlock(&area->lock);	498	spinlock_unlock(&area->lock);
499	spinlock_unlock(&as->lock);	499	spinlock_unlock(&as->lock);
500	interrupts_restore(ipl);	500	interrupts_restore(ipl);

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/mm/as.c @ 1757 – Rev 1147 → 1148