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.
 */
 
/**
 * @file    as.c
 * @brief   Address space related functions.
 *
 * This file contains address space manipulation functions.
 * Roughly speaking, this is a higher-level client of
 * Virtual Address Translation (VAT) subsystem.
 *
 * Functionality provided by this file allows one to
 * create address space and create, resize and share
 * address space areas.
 *
 * @see page.c
 *
 */
 
#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 <synch/spinlock.h>
#include <synch/mutex.h>
#include <adt/list.h>
#include <adt/btree.h>
#include <proc/task.h>
#include <proc/thread.h>
#include <arch/asm.h>
#include <panic.h>
#include <debug.h>
#include <print.h>
#include <memstr.h>
#include <macros.h>
#include <arch.h>
#include <errno.h>
#include <config.h>
#include <align.h>
#include <arch/types.h>
#include <typedefs.h>
#include <syscall/copy.h>
#include <arch/interrupt.h>
 
as_operations_t *as_operations = NULL;
 
/** Address space lock. It protects inactive_as_with_asid_head. Must be acquired before as_t mutex. */
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 area_flags_to_page_flags(int aflags);
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);
static int used_space_insert(as_area_t *a, __address page, count_t count);
static int used_space_remove(as_area_t *a, __address page, count_t count);
 
/** 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);
    mutex_initialize(&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 memory.
 * @param size Size of area.
 * @param base Base address of area.
 * @param attrs Attributes of the 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, int attrs)
{
    ipl_t ipl;
    as_area_t *a;
   
    if (base % PAGE_SIZE)
        return NULL;
 
    if (!size)
        return NULL;
 
    /* Writeable executable areas are not supported. */
    if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
        return NULL;
   
    ipl = interrupts_disable();
    mutex_lock(&as->lock);
   
    if (!check_area_conflicts(as, base, size, NULL)) {
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return NULL;
    }
   
    a = (as_area_t *) malloc(sizeof(as_area_t), 0);
 
    mutex_initialize(&a->lock);
   
    a->flags = flags;
    a->attributes = attrs;
    a->pages = SIZE2FRAMES(size);
    a->base = base;
    btree_create(&a->used_space);
   
    btree_insert(&as->as_area_btree, base, (void *) a, NULL);
 
    mutex_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return a;
}
 
/** 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 Zero on success or a value from @ref errno.h otherwise.
 */
int as_area_resize(as_t *as, __address address, size_t size, int flags)
{
    as_area_t *area;
    ipl_t ipl;
    size_t pages;
   
    ipl = interrupts_disable();
    mutex_lock(&as->lock);
   
    /*
     * Locate the area.
     */
    area = find_area_and_lock(as, address);
    if (!area) {
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return ENOENT;
    }
 
    if (area->flags & AS_AREA_DEVICE) {
        /*
         * Remapping of address space areas associated
         * with memory mapped devices is not supported.
         */
        mutex_unlock(&area->lock);
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return ENOTSUP;
    }
 
    pages = SIZE2FRAMES((address - area->base) + size);
    if (!pages) {
        /*
         * Zero size address space areas are not allowed.
         */
        mutex_unlock(&area->lock);
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return EPERM;
    }
   
    if (pages < area->pages) {
        bool cond;
        __address start_free = area->base + pages*PAGE_SIZE;
 
        /*
         * Shrinking the area.
         * No need to check for overlaps.
         */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
        /*
         * Remove frames belonging to used space starting from
         * the highest addresses downwards until an overlap with
         * the resized address space area is found. Note that this
         * is also the right way to remove part of the used_space
         * B+tree leaf list.
         */    
        for (cond = true; cond;) {
            btree_node_t *node;
       
            ASSERT(!list_empty(&area->used_space.leaf_head));
            node = list_get_instance(area->used_space.leaf_head.prev, btree_node_t, leaf_link);
            if ((cond = (bool) node->keys)) {
                __address b = node->key[node->keys - 1];
                count_t c = (count_t) node->value[node->keys - 1];
                int i = 0;
           
                if (overlaps(b, c*PAGE_SIZE, area->base, pages*PAGE_SIZE)) {
                   
                    if (b + c*PAGE_SIZE <= start_free) {
                        /*
                         * The whole interval fits completely
                         * in the resized address space area.
                         */
                        break;
                    }
       
                    /*
                     * Part of the interval corresponding to b and c
                     * overlaps with the resized address space area.
                     */
       
                    cond = false;   /* we are almost done */
                    i = (start_free - b) >> PAGE_WIDTH;
                    if (!used_space_remove(area, start_free, c - i))
                        panic("Could not remove used space.");
                } else {
                    /*
                     * The interval of used space can be completely removed.
                     */
                    if (!used_space_remove(area, b, c))
                        panic("Could not remove used space.\n");
                }
           
                for (; i < c; i++) {
                    pte_t *pte;
           
                    page_table_lock(as, false);
                    pte = page_mapping_find(as, b + i*PAGE_SIZE);
                    ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
                    frame_free(ADDR2PFN(PTE_GET_FRAME(pte)));
                    page_mapping_remove(as, b + i*PAGE_SIZE);
                    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)) {
            mutex_unlock(&area->lock);
            mutex_unlock(&as->lock);       
            interrupts_restore(ipl);
            return EADDRNOTAVAIL;
        }
    }
 
    area->pages = pages;
   
    mutex_unlock(&area->lock);
    mutex_unlock(&as->lock);
    interrupts_restore(ipl);
 
    return 0;
}
 
/** Destroy address space area.
 *
 * @param as Address space.
 * @param address Address withing the area to be deleted.
 *
 * @return Zero on success or a value from @ref errno.h on failure.
 */
int as_area_destroy(as_t *as, __address address)
{
    as_area_t *area;
    __address base;
    ipl_t ipl;
 
 
    ipl = interrupts_disable();
    mutex_lock(&as->lock);
 
    area = find_area_and_lock(as, address);
    if (!area) {
        mutex_unlock(&as->lock);
        interrupts_restore(ipl);
        return ENOENT;
    }
 
    base = area->base;
    if (!(area->flags & AS_AREA_DEVICE)) {
        bool cond; 
   
        /*
         * Releasing physical memory.
         * Areas mapping memory-mapped devices are treated differently than
         * areas backing frame_alloc()'ed memory.
         */
 
        /*
         * Visit only the pages mapped by used_space B+tree.
         * Note that we must be very careful when walking the tree
         * leaf list and removing used space as the leaf list changes
         * unpredictibly after each remove. The solution is to actually
         * not walk the tree at all, but to remove items from the head
         * of the leaf list until there are some keys left.
         */
        for (cond = true; cond;) {
            btree_node_t *node;
       
            ASSERT(!list_empty(&area->used_space.leaf_head));
            node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);
            if ((cond = (bool) node->keys)) {
                __address b = node->key[0];
                count_t i;
                pte_t *pte;
           
                for (i = 0; i < (count_t) node->value[0]; i++) {
                    page_table_lock(as, false);
                    pte = page_mapping_find(as, b + i*PAGE_SIZE);
                    ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
                    frame_free(ADDR2PFN(PTE_GET_FRAME(pte)));
                    page_mapping_remove(as, b + i*PAGE_SIZE);
                    page_table_unlock(as, false);
                }
                if (!used_space_remove(area, b, i))
                    panic("Could not remove used space.\n");
            }
 
 
 
        }
    }
    btree_destroy(&area->used_space);
 
    /*
     * Invalidate TLB's.
     */
    tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base, area->pages);
    tlb_invalidate_pages(AS->asid, area->base, area->pages);
    tlb_shootdown_finalize();
 
    area->attributes |= AS_AREA_ATTR_PARTIAL;
    mutex_unlock(&area->lock);
 
    /*
     * Remove the empty area from address space.
     */
    btree_remove(&AS->as_area_btree, base, NULL);
   
    free(area);
   
    mutex_unlock(&AS->lock);
    interrupts_restore(ipl);
    return 0;
}
 
/** Steal address space area from another task.
 *
 * Address space area is stolen from another task
 * Moreover, any existing mapping
 * is copied as well, providing thus a mechanism
 * for sharing group of pages. The source address
 * space area and any associated mapping is preserved.
 *
 * @param src_task Pointer of source task
 * @param src_base Base address of the source address space area.
 * @param acc_size Expected size of the source area
 * @param dst_base Target base address
 *
 * @return Zero on success or ENOENT if there is no such task or
 *     if there is no such address space area,
 *     EPERM if there was a problem in accepting the area or
 *     ENOMEM if there was a problem in allocating destination
 *     address space area.
 */
int as_area_steal(task_t *src_task, __address src_base, size_t acc_size,
          __address dst_base)
{
    ipl_t ipl;
    count_t i;
    as_t *src_as;      
    int src_flags;
    size_t src_size;
    as_area_t *src_area, *dst_area;
 
    ipl = interrupts_disable();
    spinlock_lock(&src_task->lock);
    src_as = src_task->as;
   
    mutex_lock(&src_as->lock);
    src_area = find_area_and_lock(src_as, src_base);
    if (!src_area) {
        /*
         * Could not find the source address space area.
         */
        spinlock_unlock(&src_task->lock);
        mutex_unlock(&src_as->lock);
        interrupts_restore(ipl);
        return ENOENT;
    }
    src_size = src_area->pages * PAGE_SIZE;
    src_flags = src_area->flags;
    mutex_unlock(&src_area->lock);
    mutex_unlock(&src_as->lock);
 
 
    if (src_size != acc_size) {
        spinlock_unlock(&src_task->lock);
        interrupts_restore(ipl);
        return EPERM;
    }
    /*
     * Create copy of the source address space area.
     * The destination area is created with AS_AREA_ATTR_PARTIAL
     * attribute set which prevents race condition with
     * preliminary as_page_fault() calls.
     */
    dst_area = as_area_create(AS, src_flags, src_size, dst_base, AS_AREA_ATTR_PARTIAL);
    if (!dst_area) {
        /*
         * Destination address space area could not be created.
         */
        spinlock_unlock(&src_task->lock);
        interrupts_restore(ipl);
        return ENOMEM;
    }
   
    spinlock_unlock(&src_task->lock);
   
    /*
     * Avoid deadlock by first locking the address space with lower address.
     */
    if (AS < src_as) {
        mutex_lock(&AS->lock);
        mutex_lock(&src_as->lock);
    } else {
        mutex_lock(&AS->lock);
        mutex_lock(&src_as->lock);
    }
   
    for (i = 0; i < SIZE2FRAMES(src_size); i++) {
        pte_t *pte;
        __address frame;
           
        page_table_lock(src_as, false);
        pte = page_mapping_find(src_as, src_base + i*PAGE_SIZE);
        if (pte && PTE_VALID(pte)) {
            ASSERT(PTE_PRESENT(pte));
            frame = PTE_GET_FRAME(pte);
            if (!(src_flags & AS_AREA_DEVICE))
                frame_reference_add(ADDR2PFN(frame));
            page_table_unlock(src_as, false);
        } else {
            page_table_unlock(src_as, false);
            continue;
        }
       
        page_table_lock(AS, false);
        page_mapping_insert(AS, dst_base + i*PAGE_SIZE, frame, area_flags_to_page_flags(src_flags));
        page_table_unlock(AS, false);
    }
 
    /*
     * Now the destination address space area has been
     * fully initialized. Clear the AS_AREA_ATTR_PARTIAL
     * attribute.
     */
    mutex_lock(&dst_area->lock);
    dst_area->attributes &= ~AS_AREA_ATTR_PARTIAL;
    mutex_unlock(&dst_area->lock);
   
    mutex_unlock(&AS->lock);
    mutex_unlock(&src_as->lock);
    interrupts_restore(ipl);
   
    return 0;
}
 
/** 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));
    if (!used_space_insert(area, page, 1))
        panic("Could not insert used space.\n");
   
    mutex_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.
 * @param istate Pointer to interrupted state.
 *
 * @return 0 on page fault, 1 on success or 2 if the fault was caused by copy_to_uspace() or copy_from_uspace().
 */
int as_page_fault(__address page, istate_t *istate)
{
    pte_t *pte;
    as_area_t *area;
    __address frame;
   
    if (!THREAD)
        return 0;
       
    ASSERT(AS);
 
    mutex_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.
         */
        mutex_unlock(&AS->lock);
        goto page_fault;
    }
 
    if (area->attributes & AS_AREA_ATTR_PARTIAL) {
        /*
         * The address space area is not fully initialized.
         * Avoid possible race by returning error.
         */
        mutex_unlock(&area->lock);
        mutex_unlock(&AS->lock);
        goto page_fault;       
    }
 
    ASSERT(!(area->flags & AS_AREA_DEVICE));
 
    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);
            mutex_unlock(&area->lock);
            mutex_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));
    if (!used_space_insert(area, ALIGN_DOWN(page, PAGE_SIZE), 1))
        panic("Could not insert used space.\n");
    page_table_unlock(AS, false);
   
    mutex_unlock(&area->lock);
    mutex_unlock(&AS->lock);
    return AS_PF_OK;
 
page_fault:
    if (!THREAD)
        return AS_PF_FAULT;
   
    if (THREAD->in_copy_from_uspace) {
        THREAD->in_copy_from_uspace = false;
        istate_set_retaddr(istate, (__address) &memcpy_from_uspace_failover_address);
    } else if (THREAD->in_copy_to_uspace) {
        THREAD->in_copy_to_uspace = false;
        istate_set_retaddr(istate, (__address) &memcpy_to_uspace_failover_address);
    } else {
        return AS_PF_FAULT;
    }
 
    return AS_PF_DEFER;
}
 
/** Switch address spaces.
 *
 * Note that this function cannot sleep as it is essentially a part of
 * the scheduling. Sleeping here would lead to deadlock on wakeup.
 *
 * @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) {
        mutex_lock_active(&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);
        }
        mutex_unlock(&old->lock);
    }
 
    /*
     * Second, prepare the new address space.
     */
    mutex_lock_active(&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);
    mutex_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();
        mutex_lock_active(&new->lock);
        new->asid = asid;
        mutex_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;
}
 
/** Convert address space area flags to page flags.
 *
 * @param aflags Flags of some address space area.
 *
 * @return Flags to be passed to page_mapping_insert().
 */
int area_flags_to_page_flags(int aflags)
{
    int flags;
 
    flags = PAGE_USER | PAGE_PRESENT;
   
    if (aflags & AS_AREA_READ)
        flags |= PAGE_READ;
       
    if (aflags & AS_AREA_WRITE)
        flags |= PAGE_WRITE;
   
    if (aflags & AS_AREA_EXEC)
        flags |= PAGE_EXEC;
   
    if (!(aflags & AS_AREA_DEVICE))
        flags |= PAGE_CACHEABLE;
       
    return flags;
}
 
/** 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)
{
    return area_flags_to_page_flags(a->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 lock 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 unlock 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 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 */
        mutex_lock(&a->lock);
        return a;
    }
   
    /*
     * Search the leaf node and the righmost record of its left neighbour
     * 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];
        mutex_lock(&a->lock);
        if ((a->base <= va) && (va < a->base + a->pages * PAGE_SIZE)) {
            return a;
        }
        mutex_unlock(&a->lock);
    }
 
    /*
     * Second, locate the left neighbour and test its last record.
     * Because of its position in the B+tree, it must have base < va.
     */
    if ((lnode = btree_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
        a = (as_area_t *) lnode->value[lnode->keys - 1];
        mutex_lock(&a->lock);
        if (va < a->base + a->pages * PAGE_SIZE) {
            return a;
        }
        mutex_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 neighbour, the leftmost record in the right
     * neighbour 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_leaf_node_left_neighbour(&as->as_area_btree, leaf))) {
        a = (as_area_t *) node->value[node->keys - 1];
        mutex_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            mutex_unlock(&a->lock);
            return false;
        }
        mutex_unlock(&a->lock);
    }
    if ((node = btree_leaf_node_right_neighbour(&as->as_area_btree, leaf))) {
        a = (as_area_t *) node->value[0];
        mutex_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            mutex_unlock(&a->lock);
            return false;
        }
        mutex_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;
   
        mutex_lock(&a->lock);
        if (overlaps(va, size, a->base, a->pages * PAGE_SIZE)) {
            mutex_unlock(&a->lock);
            return false;
        }
        mutex_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;
}
 
/** Return size of the address space area with given base.  */
size_t as_get_size(__address base)
{
    ipl_t ipl;
    as_area_t *src_area;
    size_t size;
 
    ipl = interrupts_disable();
    src_area = find_area_and_lock(AS, base);
    if (src_area){
        size = src_area->pages * PAGE_SIZE;
        mutex_unlock(&src_area->lock);
    } else {
        size = 0;
    }
    interrupts_restore(ipl);
    return size;
}
 
/** Mark portion of address space area as used.
 *
 * The address space area must be already locked.
 *
 * @param a Address space area.
 * @param page First page to be marked.
 * @param count Number of page to be marked.
 *
 * @return 0 on failure and 1 on success.
 */
int used_space_insert(as_area_t *a, __address page, count_t count)
{
    btree_node_t *leaf, *node;
    count_t pages;
    int i;
 
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
    ASSERT(count);
 
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
    if (pages) {
        /*
         * We hit the beginning of some used space.
         */
        return 0;
    }
 
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
    if (node) {
        __address left_pg = node->key[node->keys - 1], right_pg = leaf->key[0];
        count_t left_cnt = (count_t) node->value[node->keys - 1], right_cnt = (count_t) leaf->value[0];
       
        /*
         * Examine the possibility that the interval fits
         * somewhere between the rightmost interval of
         * the left neigbour and the first interval of the leaf.
         */
         
        if (page >= right_pg) {
            /* Do nothing. */
        } else if (overlaps(page, count*PAGE_SIZE, left_pg, left_cnt*PAGE_SIZE)) {
            /* The interval intersects with the left interval. */
            return 0;
        } else if (overlaps(page, count*PAGE_SIZE, right_pg, right_cnt*PAGE_SIZE)) {
            /* The interval intersects with the right interval. */
            return 0;          
        } else if ((page == left_pg + left_cnt*PAGE_SIZE) && (page + count*PAGE_SIZE == right_pg)) {
            /* The interval can be added by merging the two already present intervals. */
            node->value[node->keys - 1] += count + right_cnt;
            btree_remove(&a->used_space, right_pg, leaf);
            return 1;
        } else if (page == left_pg + left_cnt*PAGE_SIZE) {
            /* The interval can be added by simply growing the left interval. */
            node->value[node->keys - 1] += count;
            return 1;
        } else if (page + count*PAGE_SIZE == right_pg) {
            /*
             * The interval can be addded by simply moving base of the right
             * interval down and increasing its size accordingly.
             */
            leaf->value[0] += count;
            leaf->key[0] = page;
            return 1;
        } else {
            /*
             * The interval is between both neigbouring intervals,
             * but cannot be merged with any of them.
             */
            btree_insert(&a->used_space, page, (void *) count, leaf);
            return 1;
        }
    } else if (page < leaf->key[0]) {
        __address right_pg = leaf->key[0];
        count_t right_cnt = (count_t) leaf->value[0];
   
        /*
         * Investigate the border case in which the left neighbour does not
         * exist but the interval fits from the left.
         */
         
        if (overlaps(page, count*PAGE_SIZE, right_pg, right_cnt*PAGE_SIZE)) {
            /* The interval intersects with the right interval. */
            return 0;
        } else if (page + count*PAGE_SIZE == right_pg) {
            /*
             * The interval can be added by moving the base of the right interval down
             * and increasing its size accordingly.
             */
            leaf->key[0] = page;
            leaf->value[0] += count;
            return 1;
        } else {
            /*
             * The interval doesn't adjoin with the right interval.
             * It must be added individually.
             */
            btree_insert(&a->used_space, page, (void *) count, leaf);
            return 1;
        }
    }
 
    node = btree_leaf_node_right_neighbour(&a->used_space, leaf);
    if (node) {
        __address left_pg = leaf->key[leaf->keys - 1], right_pg = node->key[0];
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1], right_cnt = (count_t) node->value[0];
       
        /*
         * Examine the possibility that the interval fits
         * somewhere between the leftmost interval of
         * the right neigbour and the last interval of the leaf.
         */
 
        if (page < left_pg) {
            /* Do nothing. */
        } else if (overlaps(page, count*PAGE_SIZE, left_pg, left_cnt*PAGE_SIZE)) {
            /* The interval intersects with the left interval. */
            return 0;
        } else if (overlaps(page, count*PAGE_SIZE, right_pg, right_cnt*PAGE_SIZE)) {
            /* The interval intersects with the right interval. */
            return 0;          
        } else if ((page == left_pg + left_cnt*PAGE_SIZE) && (page + count*PAGE_SIZE == right_pg)) {
            /* The interval can be added by merging the two already present intervals. */
            leaf->value[leaf->keys - 1] += count + right_cnt;
            btree_remove(&a->used_space, right_pg, node);
            return 1;
        } else if (page == left_pg + left_cnt*PAGE_SIZE) {
            /* The interval can be added by simply growing the left interval. */
            leaf->value[leaf->keys - 1] +=  count;
            return 1;
        } else if (page + count*PAGE_SIZE == right_pg) {
            /*
             * The interval can be addded by simply moving base of the right
             * interval down and increasing its size accordingly.
             */
            node->value[0] += count;
            node->key[0] = page;
            return 1;
        } else {
            /*
             * The interval is between both neigbouring intervals,
             * but cannot be merged with any of them.
             */
            btree_insert(&a->used_space, page, (void *) count, leaf);
            return 1;
        }
    } else if (page >= leaf->key[leaf->keys - 1]) {
        __address left_pg = leaf->key[leaf->keys - 1];
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
   
        /*
         * Investigate the border case in which the right neighbour does not
         * exist but the interval fits from the right.
         */
         
        if (overlaps(page, count*PAGE_SIZE, left_pg, left_cnt*PAGE_SIZE)) {
            /* The interval intersects with the left interval. */
            return 0;
        } else if (left_pg + left_cnt*PAGE_SIZE == page) {
            /* The interval can be added by growing the left interval. */
            leaf->value[leaf->keys - 1] += count;
            return 1;
        } else {
            /*
             * The interval doesn't adjoin with the left interval.
             * It must be added individually.
             */
            btree_insert(&a->used_space, page, (void *) count, leaf);
            return 1;
        }
    }
   
    /*
     * Note that if the algorithm made it thus far, the interval can fit only
     * between two other intervals of the leaf. The two border cases were already
     * resolved.
     */
    for (i = 1; i < leaf->keys; i++) {
        if (page < leaf->key[i]) {
            __address left_pg = leaf->key[i - 1], right_pg = leaf->key[i];
            count_t left_cnt = (count_t) leaf->value[i - 1], right_cnt = (count_t) leaf->value[i];
 
            /*
             * The interval fits between left_pg and right_pg.
             */
 
            if (overlaps(page, count*PAGE_SIZE, left_pg, left_cnt*PAGE_SIZE)) {
                /* The interval intersects with the left interval. */
                return 0;
            } else if (overlaps(page, count*PAGE_SIZE, right_pg, right_cnt*PAGE_SIZE)) {
                /* The interval intersects with the right interval. */
                return 0;          
            } else if ((page == left_pg + left_cnt*PAGE_SIZE) && (page + count*PAGE_SIZE == right_pg)) {
                /* The interval can be added by merging the two already present intervals. */
                leaf->value[i - 1] += count + right_cnt;
                btree_remove(&a->used_space, right_pg, leaf);
                return 1;
            } else if (page == left_pg + left_cnt*PAGE_SIZE) {
                /* The interval can be added by simply growing the left interval. */
                leaf->value[i - 1] += count;
                return 1;
            } else if (page + count*PAGE_SIZE == right_pg) {
                /*
                     * The interval can be addded by simply moving base of the right
                 * interval down and increasing its size accordingly.
                 */
                leaf->value[i] += count;
                leaf->key[i] = page;
                return 1;
            } else {
                /*
                 * The interval is between both neigbouring intervals,
                 * but cannot be merged with any of them.
                 */
                btree_insert(&a->used_space, page, (void *) count, leaf);
                return 1;
            }
        }
    }
 
    panic("Inconsistency detected while adding %d pages of used space at %P.\n", count, page);
}
 
/** Mark portion of address space area as unused.
 *
 * The address space area must be already locked.
 *
 * @param a Address space area.
 * @param page First page to be marked.
 * @param count Number of page to be marked.
 *
 * @return 0 on failure and 1 on success.
 */
int used_space_remove(as_area_t *a, __address page, count_t count)
{
    btree_node_t *leaf, *node;
    count_t pages;
    int i;
 
    ASSERT(page == ALIGN_DOWN(page, PAGE_SIZE));
    ASSERT(count);
 
    pages = (count_t) btree_search(&a->used_space, page, &leaf);
    if (pages) {
        /*
         * We are lucky, page is the beginning of some interval.
         */
        if (count > pages) {
            return 0;
        } else if (count == pages) {
            btree_remove(&a->used_space, page, leaf);
            return 1;
        } else {
            /*
             * Find the respective interval.
             * Decrease its size and relocate its start address.
             */
            for (i = 0; i < leaf->keys; i++) {
                if (leaf->key[i] == page) {
                    leaf->key[i] += count*PAGE_SIZE;
                    leaf->value[i] -= count;
                    return 1;
                }
            }
            goto error;
        }
    }
 
    node = btree_leaf_node_left_neighbour(&a->used_space, leaf);
    if (node && page < leaf->key[0]) {
        __address left_pg = node->key[node->keys - 1];
        count_t left_cnt = (count_t) node->value[node->keys - 1];
 
        if (overlaps(left_pg, left_cnt*PAGE_SIZE, page, count*PAGE_SIZE)) {
            if (page + count*PAGE_SIZE == left_pg + left_cnt*PAGE_SIZE) {
                /*
                 * The interval is contained in the rightmost interval
                 * of the left neighbour and can be removed by
                 * updating the size of the bigger interval.
                 */
                node->value[node->keys - 1] -= count;
                return 1;
            } else if (page + count*PAGE_SIZE < left_pg + left_cnt*PAGE_SIZE) {
                count_t new_cnt;
               
                /*
                 * The interval is contained in the rightmost interval
                 * of the left neighbour but its removal requires
                 * both updating the size of the original interval and
                 * also inserting a new interval.
                 */
                new_cnt = ((left_pg + left_cnt*PAGE_SIZE) - (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
                node->value[node->keys - 1] -= count + new_cnt;
                btree_insert(&a->used_space, page + count*PAGE_SIZE, (void *) new_cnt, leaf);
                return 1;
            }
        }
        return 0;
    } else if (page < leaf->key[0]) {
        return 0;
    }
   
    if (page > leaf->key[leaf->keys - 1]) {
        __address left_pg = leaf->key[leaf->keys - 1];
        count_t left_cnt = (count_t) leaf->value[leaf->keys - 1];
 
        if (overlaps(left_pg, left_cnt*PAGE_SIZE, page, count*PAGE_SIZE)) {
            if (page + count*PAGE_SIZE == left_pg + left_cnt*PAGE_SIZE) {
                /*
                 * The interval is contained in the rightmost interval
                 * of the leaf and can be removed by updating the size
                 * of the bigger interval.
                 */
                leaf->value[leaf->keys - 1] -= count;
                return 1;
            } else if (page + count*PAGE_SIZE < left_pg + left_cnt*PAGE_SIZE) {
                count_t new_cnt;
               
                /*
                 * The interval is contained in the rightmost interval
                 * of the leaf but its removal requires both updating
                 * the size of the original interval and
                 * also inserting a new interval.
                 */
                new_cnt = ((left_pg + left_cnt*PAGE_SIZE) - (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
                leaf->value[leaf->keys - 1] -= count + new_cnt;
                btree_insert(&a->used_space, page + count*PAGE_SIZE, (void *) new_cnt, leaf);
                return 1;
            }
        }
        return 0;
    }  
   
    /*
     * The border cases have been already resolved.
     * Now the interval can be only between intervals of the leaf.
     */
    for (i = 1; i < leaf->keys - 1; i++) {
        if (page < leaf->key[i]) {
            __address left_pg = leaf->key[i - 1];
            count_t left_cnt = (count_t) leaf->value[i - 1];
 
            /*
             * Now the interval is between intervals corresponding to (i - 1) and i.
             */
            if (overlaps(left_pg, left_cnt*PAGE_SIZE, page, count*PAGE_SIZE)) {
                if (page + count*PAGE_SIZE == left_pg + left_cnt*PAGE_SIZE) {
                    /*
                    * The interval is contained in the interval (i - 1)
                     * of the leaf and can be removed by updating the size
                     * of the bigger interval.
                     */
                    leaf->value[i - 1] -= count;
                    return 1;
                } else if (page + count*PAGE_SIZE < left_pg + left_cnt*PAGE_SIZE) {
                    count_t new_cnt;
               
                    /*
                     * The interval is contained in the interval (i - 1)
                     * of the leaf but its removal requires both updating
                     * the size of the original interval and
                     * also inserting a new interval.
                     */
                    new_cnt = ((left_pg + left_cnt*PAGE_SIZE) - (page + count*PAGE_SIZE)) >> PAGE_WIDTH;
                    leaf->value[i - 1] -= count + new_cnt;
                    btree_insert(&a->used_space, page + count*PAGE_SIZE, (void *) new_cnt, leaf);
                    return 1;
                }
            }
            return 0;
        }
    }
 
error:
    panic("Inconsistency detected while removing %d pages of used space from %P.\n", count, page);
}
 
/*
 * Address space related syscalls.
 */
 
/** Wrapper for as_area_create(). */
__native sys_as_area_create(__address address, size_t size, int flags)
{
    if (as_area_create(AS, flags, size, address, AS_AREA_ATTR_NONE))
        return (__native) address;
    else
        return (__native) -1;
}
 
/** Wrapper for as_area_resize. */
__native sys_as_area_resize(__address address, size_t size, int flags)
{
    return (__native) as_area_resize(AS, address, size, 0);
}
 
/** Wrapper for as_area_destroy. */
__native sys_as_area_destroy(__address address)
{
    return (__native) as_area_destroy(AS, address);
}
 

Rev 1387	Rev 1403
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	* @file as.c	30	* @file as.c
31	* @brief Address space related functions.	31	* @brief Address space related functions.
32	*	32	*
33	* This file contains address space manipulation functions.	33	* This file contains address space manipulation functions.
34	* Roughly speaking, this is a higher-level client of	34	* Roughly speaking, this is a higher-level client of
35	* Virtual Address Translation (VAT) subsystem.	35	* Virtual Address Translation (VAT) subsystem.
36	*	36	*
37	* Functionality provided by this file allows one to	37	* Functionality provided by this file allows one to
38	* create address space and create, resize and share	38	* create address space and create, resize and share
39	* address space areas.	39	* address space areas.
40	*	40	*
41	* @see page.c	41	* @see page.c
42	*	42	*
43	*/	43	*/
44		44
45	#include <mm/as.h>	45	#include <mm/as.h>
46	#include <arch/mm/as.h>	46	#include <arch/mm/as.h>
47	#include <mm/page.h>	47	#include <mm/page.h>
48	#include <mm/frame.h>	48	#include <mm/frame.h>
49	#include <mm/slab.h>	49	#include <mm/slab.h>
50	#include <mm/tlb.h>	50	#include <mm/tlb.h>
51	#include <arch/mm/page.h>	51	#include <arch/mm/page.h>
52	#include <genarch/mm/page_pt.h>	52	#include <genarch/mm/page_pt.h>
53	#include <genarch/mm/page_ht.h>	53	#include <genarch/mm/page_ht.h>
54	#include <mm/asid.h>	54	#include <mm/asid.h>
55	#include <arch/mm/asid.h>	55	#include <arch/mm/asid.h>
56	#include <synch/spinlock.h>	56	#include <synch/spinlock.h>
57	#include <synch/mutex.h>	57	#include <synch/mutex.h>
58	#include <adt/list.h>	58	#include <adt/list.h>
59	#include <adt/btree.h>	59	#include <adt/btree.h>
60	#include <proc/task.h>	60	#include <proc/task.h>
61	#include <proc/thread.h>	61	#include <proc/thread.h>
62	#include <arch/asm.h>	62	#include <arch/asm.h>
63	#include <panic.h>	63	#include <panic.h>
64	#include <debug.h>	64	#include <debug.h>
65	#include <print.h>	65	#include <print.h>
66	#include <memstr.h>	66	#include <memstr.h>
67	#include <macros.h>	67	#include <macros.h>
68	#include <arch.h>	68	#include <arch.h>
69	#include <errno.h>	69	#include <errno.h>
70	#include <config.h>	70	#include <config.h>
71	#include <align.h>	71	#include <align.h>
72	#include <arch/types.h>	72	#include <arch/types.h>
73	#include <typedefs.h>	73	#include <typedefs.h>
74	#include <syscall/copy.h>	74	#include <syscall/copy.h>
75	#include <arch/interrupt.h>	75	#include <arch/interrupt.h>
76		76
77	as_operations_t *as_operations = NULL;	77	as_operations_t *as_operations = NULL;
78		78
79	/** Address space lock. It protects inactive_as_with_asid_head. Must be acquired before as_t mutex. */	79	/** Address space lock. It protects inactive_as_with_asid_head. Must be acquired before as_t mutex. */
80	SPINLOCK_INITIALIZE(as_lock);	80	SPINLOCK_INITIALIZE(as_lock);
81		81
82	/**	82	/**
83	* This list contains address spaces that are not active on any	83	* This list contains address spaces that are not active on any
84	* processor and that have valid ASID.	84	* processor and that have valid ASID.
85	*/	85	*/
86	LIST_INITIALIZE(inactive_as_with_asid_head);	86	LIST_INITIALIZE(inactive_as_with_asid_head);
87		87
88	/** Kernel address space. */	88	/** Kernel address space. */
89	as_t *AS_KERNEL = NULL;	89	as_t *AS_KERNEL = NULL;
90		90
91	static int area_flags_to_page_flags(int aflags);	91	static int area_flags_to_page_flags(int aflags);
92	static int get_area_flags(as_area_t *a);	92	static int get_area_flags(as_area_t *a);
93	static as_area_t find_area_and_lock(as_t as, __address va);	93	static as_area_t find_area_and_lock(as_t as, __address va);
94	static bool check_area_conflicts(as_t as, __address va, size_t size, as_area_t avoid_area);	94	static bool check_area_conflicts(as_t as, __address va, size_t size, as_area_t avoid_area);
95	int used_space_insert(as_area_t *a, __address page, count_t count);	95	static int used_space_insert(as_area_t *a, __address page, count_t count);
96	int used_space_remove(as_area_t *a, __address page, count_t count);	96	static int used_space_remove(as_area_t *a, __address page, count_t count);
97		97
98	/** Initialize address space subsystem. */	98	/** Initialize address space subsystem. */
99	void as_init(void)	99	void as_init(void)
100	{	100	{
101	as_arch_init();	101	as_arch_init();
102	AS_KERNEL = as_create(FLAG_AS_KERNEL);	102	AS_KERNEL = as_create(FLAG_AS_KERNEL);
103	if (!AS_KERNEL)	103	if (!AS_KERNEL)
104	panic("can't create kernel address space\n");	104	panic("can't create kernel address space\n");
105		105
106	}	106	}
107		107
108	/** Create address space.	108	/** Create address space.
109	*	109	*
110	* @param flags Flags that influence way in wich the address space is created.	110	* @param flags Flags that influence way in wich the address space is created.
111	*/	111	*/
112	as_t *as_create(int flags)	112	as_t *as_create(int flags)
113	{	113	{
114	as_t *as;	114	as_t *as;
115		115
116	as = (as_t *) malloc(sizeof(as_t), 0);	116	as = (as_t *) malloc(sizeof(as_t), 0);
117	link_initialize(&as->inactive_as_with_asid_link);	117	link_initialize(&as->inactive_as_with_asid_link);
118	mutex_initialize(&as->lock);	118	mutex_initialize(&as->lock);
119	btree_create(&as->as_area_btree);	119	btree_create(&as->as_area_btree);
120		120
121	if (flags & FLAG_AS_KERNEL)	121	if (flags & FLAG_AS_KERNEL)
122	as->asid = ASID_KERNEL;	122	as->asid = ASID_KERNEL;
123	else	123	else
124	as->asid = ASID_INVALID;	124	as->asid = ASID_INVALID;
125		125
126	as->refcount = 0;	126	as->refcount = 0;
127	as->page_table = page_table_create(flags);	127	as->page_table = page_table_create(flags);
128		128
129	return as;	129	return as;
130	}	130	}
131		131
132	/** Free Adress space */	132	/** Free Adress space */
133	void as_free(as_t *as)	133	void as_free(as_t *as)
134	{	134	{
135	ASSERT(as->refcount == 0);	135	ASSERT(as->refcount == 0);
136		136
137	/* TODO: free as_areas and other resources held by as */	137	/* TODO: free as_areas and other resources held by as */
138	/* TODO: free page table */	138	/* TODO: free page table */
139	free(as);	139	free(as);
140	}	140	}
141		141
142	/** Create address space area of common attributes.	142	/** Create address space area of common attributes.
143	*	143	*
144	* The created address space area is added to the target address space.	144	* The created address space area is added to the target address space.
145	*	145	*
146	* @param as Target address space.	146	* @param as Target address space.
147	* @param flags Flags of the area memory.	147	* @param flags Flags of the area memory.
148	* @param size Size of area.	148	* @param size Size of area.
149	* @param base Base address of area.	149	* @param base Base address of area.
150	* @param attrs Attributes of the area.	150	* @param attrs Attributes of the area.
151	*	151	*
152	* @return Address space area on success or NULL on failure.	152	* @return Address space area on success or NULL on failure.
153	*/	153	*/
154	as_area_t as_area_create(as_t as, int flags, size_t size, __address base, int attrs)	154	as_area_t as_area_create(as_t as, int flags, size_t size, __address base, int attrs)
155	{	155	{
156	ipl_t ipl;	156	ipl_t ipl;
157	as_area_t *a;	157	as_area_t *a;
158		158
159	if (base % PAGE_SIZE)	159	if (base % PAGE_SIZE)
160	return NULL;	160	return NULL;
161		161
162	if (!size)	162	if (!size)
163	return NULL;	163	return NULL;
164		164
165	/* Writeable executable areas are not supported. */	165	/* Writeable executable areas are not supported. */
166	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))	166	if ((flags & AS_AREA_EXEC) && (flags & AS_AREA_WRITE))
167	return NULL;	167	return NULL;
168		168
169	ipl = interrupts_disable();	169	ipl = interrupts_disable();
170	mutex_lock(&as->lock);	170	mutex_lock(&as->lock);
171		171
172	if (!check_area_conflicts(as, base, size, NULL)) {	172	if (!check_area_conflicts(as, base, size, NULL)) {
173	mutex_unlock(&as->lock);	173	mutex_unlock(&as->lock);
174	interrupts_restore(ipl);	174	interrupts_restore(ipl);
175	return NULL;	175	return NULL;
176	}	176	}
177		177
178	a = (as_area_t *) malloc(sizeof(as_area_t), 0);	178	a = (as_area_t *) malloc(sizeof(as_area_t), 0);
179		179
180	mutex_initialize(&a->lock);	180	mutex_initialize(&a->lock);
181		181
182	a->flags = flags;	182	a->flags = flags;
183	a->attributes = attrs;	183	a->attributes = attrs;
184	a->pages = SIZE2FRAMES(size);	184	a->pages = SIZE2FRAMES(size);
185	a->base = base;	185	a->base = base;
186	btree_create(&a->used_space);	186	btree_create(&a->used_space);
187		187
188	btree_insert(&as->as_area_btree, base, (void *) a, NULL);	188	btree_insert(&as->as_area_btree, base, (void *) a, NULL);
189		189
190	mutex_unlock(&as->lock);	190	mutex_unlock(&as->lock);
191	interrupts_restore(ipl);	191	interrupts_restore(ipl);
192		192
193	return a;	193	return a;
194	}	194	}
195		195
196	/** Find address space area and change it.	196	/** Find address space area and change it.
197	*	197	*
198	* @param as Address space.	198	* @param as Address space.
199	* @param address Virtual address belonging to the area to be changed. Must be page-aligned.	199	* @param address Virtual address belonging to the area to be changed. Must be page-aligned.
200	* @param size New size of the virtual memory block starting at address.	200	* @param size New size of the virtual memory block starting at address.
201	* @param flags Flags influencing the remap operation. Currently unused.	201	* @param flags Flags influencing the remap operation. Currently unused.
202	*	202	*
203	* @return Zero on success or a value from @ref errno.h otherwise.	203	* @return Zero on success or a value from @ref errno.h otherwise.
204	*/	204	*/
205	int as_area_resize(as_t *as, __address address, size_t size, int flags)	205	int as_area_resize(as_t *as, __address address, size_t size, int flags)
206	{	206	{
207	as_area_t *area;	207	as_area_t *area;
208	ipl_t ipl;	208	ipl_t ipl;
209	size_t pages;	209	size_t pages;
210		210
211	ipl = interrupts_disable();	211	ipl = interrupts_disable();
212	mutex_lock(&as->lock);	212	mutex_lock(&as->lock);
213		213
214	/*	214	/*
215	* Locate the area.	215	* Locate the area.
216	*/	216	*/
217	area = find_area_and_lock(as, address);	217	area = find_area_and_lock(as, address);
218	if (!area) {	218	if (!area) {
219	mutex_unlock(&as->lock);	219	mutex_unlock(&as->lock);
220	interrupts_restore(ipl);	220	interrupts_restore(ipl);
221	return ENOENT;	221	return ENOENT;
222	}	222	}
223		223
224	if (area->flags & AS_AREA_DEVICE) {	224	if (area->flags & AS_AREA_DEVICE) {
225	/*	225	/*
226	* Remapping of address space areas associated	226	* Remapping of address space areas associated
227	* with memory mapped devices is not supported.	227	* with memory mapped devices is not supported.
228	*/	228	*/
229	mutex_unlock(&area->lock);	229	mutex_unlock(&area->lock);
230	mutex_unlock(&as->lock);	230	mutex_unlock(&as->lock);
231	interrupts_restore(ipl);	231	interrupts_restore(ipl);
232	return ENOTSUP;	232	return ENOTSUP;
233	}	233	}
234		234
235	pages = SIZE2FRAMES((address - area->base) + size);	235	pages = SIZE2FRAMES((address - area->base) + size);
236	if (!pages) {	236	if (!pages) {
237	/*	237	/*
238	* Zero size address space areas are not allowed.	238	* Zero size address space areas are not allowed.
239	*/	239	*/
240	mutex_unlock(&area->lock);	240	mutex_unlock(&area->lock);
241	mutex_unlock(&as->lock);	241	mutex_unlock(&as->lock);
242	interrupts_restore(ipl);	242	interrupts_restore(ipl);
243	return EPERM;	243	return EPERM;
244	}	244	}
245		245
246	if (pages < area->pages) {	246	if (pages < area->pages) {
247	int i;	247	bool cond;
-		248	__address start_free = area->base + pages*PAGE_SIZE;
248		249
249	/*	250	/*
250	* Shrinking the area.	251	* Shrinking the area.
251	* No need to check for overlaps.	252	* No need to check for overlaps.
252	*/	253	*/
253	for (i = pages; i < area->pages; i++) {	-
254	pte_t *pte;	-
255		-
256	/*	-
257	* Releasing physical memory.	-
258	* This depends on the fact that the memory was allocated using frame_alloc().	-
259	*/	-
260	page_table_lock(as, false);	-
261	pte = page_mapping_find(as, area->base + i*PAGE_SIZE);	-
262	if (pte && PTE_VALID(pte)) {	-
263	__address frame;	-
264		-
265	ASSERT(PTE_PRESENT(pte));	-
266	frame = PTE_GET_FRAME(pte);	-
267	page_mapping_remove(as, area->base + i*PAGE_SIZE);	-
268	page_table_unlock(as, false);	-
269		254
-		255	/*
-		256	* Remove frames belonging to used space starting from
-		257	* the highest addresses downwards until an overlap with
-		258	* the resized address space area is found. Note that this
-		259	* is also the right way to remove part of the used_space
-		260	* B+tree leaf list.
-		261	*/
-		262	for (cond = true; cond;) {
-		263	btree_node_t *node;
-		264
-		265	ASSERT(!list_empty(&area->used_space.leaf_head));
-		266	node = list_get_instance(area->used_space.leaf_head.prev, btree_node_t, leaf_link);
-		267	if ((cond = (bool) node->keys)) {
-		268	__address b = node->key[node->keys - 1];
-		269	count_t c = (count_t) node->value[node->keys - 1];
-		270	int i = 0;
-		271
-		272	if (overlaps(b, cPAGE_SIZE, area->base, pagesPAGE_SIZE)) {
-		273
-		274	if (b + c*PAGE_SIZE <= start_free) {
-		275	/*
-		276	* The whole interval fits completely
-		277	* in the resized address space area.
-		278	*/
-		279	break;
-		280	}
-		281
-		282	/*
-		283	* Part of the interval corresponding to b and c
-		284	* overlaps with the resized address space area.
-		285	*/
-		286
-		287	cond = false; /* we are almost done */
270	frame_free(ADDR2PFN(frame));	288	i = (start_free - b) >> PAGE_WIDTH;
-		289	if (!used_space_remove(area, start_free, c - i))
-		290	panic("Could not remove used space.");
271	} else {	291	} else {
-		292	/*
-		293	* The interval of used space can be completely removed.
-		294	*/
-		295	if (!used_space_remove(area, b, c))
-		296	panic("Could not remove used space.\n");
-		297	}
-		298
-		299	for (; i < c; i++) {
-		300	pte_t *pte;
-		301
-		302	page_table_lock(as, false);
-		303	pte = page_mapping_find(as, b + i*PAGE_SIZE);
-		304	ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
-		305	frame_free(ADDR2PFN(PTE_GET_FRAME(pte)));
-		306	page_mapping_remove(as, b + i*PAGE_SIZE);
272	page_table_unlock(as, false);	307	page_table_unlock(as, false);
-		308	}
273	}	309	}
274	}	310	}
275	/*	311	/*
276	* Invalidate TLB's.	312	* Invalidate TLB's.
277	*/	313	*/
278	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);	314	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);
279	tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);	315	tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages);
280	tlb_shootdown_finalize();	316	tlb_shootdown_finalize();
281	} else {	317	} else {
282	/*	318	/*
283	* Growing the area.	319	* Growing the area.
284	* Check for overlaps with other address space areas.	320	* Check for overlaps with other address space areas.
285	*/	321	*/
286	if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {	322	if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) {
287	mutex_unlock(&area->lock);	323	mutex_unlock(&area->lock);
288	mutex_unlock(&as->lock);	324	mutex_unlock(&as->lock);
289	interrupts_restore(ipl);	325	interrupts_restore(ipl);
290	return EADDRNOTAVAIL;	326	return EADDRNOTAVAIL;
291	}	327	}
292	}	328	}
293		329
294	area->pages = pages;	330	area->pages = pages;
295		331
296	mutex_unlock(&area->lock);	332	mutex_unlock(&area->lock);
297	mutex_unlock(&as->lock);	333	mutex_unlock(&as->lock);
298	interrupts_restore(ipl);	334	interrupts_restore(ipl);
299		335
300	return 0;	336	return 0;
301	}	337	}
302		338
303	/** Destroy address space area.	339	/** Destroy address space area.
304	*	340	*
305	* @param as Address space.	341	* @param as Address space.
306	* @param address Address withing the area to be deleted.	342	* @param address Address withing the area to be deleted.
307	*	343	*
308	* @return Zero on success or a value from @ref errno.h on failure.	344	* @return Zero on success or a value from @ref errno.h on failure.
309	*/	345	*/
310	int as_area_destroy(as_t *as, __address address)	346	int as_area_destroy(as_t *as, __address address)
311	{	347	{
312	as_area_t *area;	348	as_area_t *area;
313	__address base;	349	__address base;
314	ipl_t ipl;	350	ipl_t ipl;
315	int i;	-
316		351
317	ipl = interrupts_disable();	352	ipl = interrupts_disable();
318	mutex_lock(&as->lock);	353	mutex_lock(&as->lock);
319		354
320	area = find_area_and_lock(as, address);	355	area = find_area_and_lock(as, address);
321	if (!area) {	356	if (!area) {
322	mutex_unlock(&as->lock);	357	mutex_unlock(&as->lock);
323	interrupts_restore(ipl);	358	interrupts_restore(ipl);
324	return ENOENT;	359	return ENOENT;
325	}	360	}
326		361
327	base = area->base;	362	base = area->base;
328	for (i = 0; i < area->pages; i++) {	363	if (!(area->flags & AS_AREA_DEVICE)) {
329	pte_t *pte;	364	bool cond;
330		365
331	/*	366	/*
332	* Releasing physical memory.	367	* Releasing physical memory.
333	* Areas mapping memory-mapped devices are treated differently than	368	* Areas mapping memory-mapped devices are treated differently than
334	* areas backing frame_alloc()'ed memory.	369	* areas backing frame_alloc()'ed memory.
335	*/	370	*/
-		371
-		372	/*
-		373	* Visit only the pages mapped by used_space B+tree.
-		374	* Note that we must be very careful when walking the tree
-		375	* leaf list and removing used space as the leaf list changes
-		376	* unpredictibly after each remove. The solution is to actually
-		377	* not walk the tree at all, but to remove items from the head
-		378	* of the leaf list until there are some keys left.
-		379	*/
-		380	for (cond = true; cond;) {
-		381	btree_node_t *node;
-		382
-		383	ASSERT(!list_empty(&area->used_space.leaf_head));
-		384	node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);
-		385	if ((cond = (bool) node->keys)) {
-		386	__address b = node->key[0];
-		387	count_t i;
-		388	pte_t *pte;
-		389
-		390	for (i = 0; i < (count_t) node->value[0]; i++) {
336	page_table_lock(as, false);	391	page_table_lock(as, false);
337	pte = page_mapping_find(as, area->base + i*PAGE_SIZE);	392	pte = page_mapping_find(as, b + i*PAGE_SIZE);
338	if (pte && PTE_VALID(pte)) {	393	ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
339	ASSERT(PTE_PRESENT(pte));	394	frame_free(ADDR2PFN(PTE_GET_FRAME(pte)));
340	page_mapping_remove(as, area->base + i*PAGE_SIZE);	395	page_mapping_remove(as, b + i*PAGE_SIZE);
341	if (area->flags & AS_AREA_DEVICE) {	396	page_table_unlock(as, false);
342	__address frame;	397	}
343	frame = PTE_GET_FRAME(pte);	398	if (!used_space_remove(area, b, i))
344	frame_free(ADDR2PFN(frame));	399	panic("Could not remove used space.\n");
345	}	400	}
346	page_table_unlock(as, false);	-
347	} else {	-
348	page_table_unlock(as, false);	-
349	}	401	}
350	}	402	}
-		403	btree_destroy(&area->used_space);
-		404
351	/*	405	/*
352	* Invalidate TLB's.	406	* Invalidate TLB's.
353	*/	407	*/
354	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base, area->pages);	408	tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base, area->pages);
355	tlb_invalidate_pages(AS->asid, area->base, area->pages);	409	tlb_invalidate_pages(AS->asid, area->base, area->pages);
356	tlb_shootdown_finalize();	410	tlb_shootdown_finalize();
357		411
358	area->attributes \|= AS_AREA_ATTR_PARTIAL;	412	area->attributes \|= AS_AREA_ATTR_PARTIAL;
359	mutex_unlock(&area->lock);	413	mutex_unlock(&area->lock);
360		414
361	/*	415	/*
362	* Remove the empty area from address space.	416	* Remove the empty area from address space.
363	*/	417	*/
364	btree_remove(&AS->as_area_btree, base, NULL);	418	btree_remove(&AS->as_area_btree, base, NULL);
365		419
366	free(area);	420	free(area);
367		421
368	mutex_unlock(&AS->lock);	422	mutex_unlock(&AS->lock);
369	interrupts_restore(ipl);	423	interrupts_restore(ipl);
370	return 0;	424	return 0;
371	}	425	}
372		426
373	/** Steal address space area from another task.	427	/** Steal address space area from another task.
374	*	428	*
375	* Address space area is stolen from another task	429	* Address space area is stolen from another task
376	* Moreover, any existing mapping	430	* Moreover, any existing mapping
377	* is copied as well, providing thus a mechanism	431	* is copied as well, providing thus a mechanism
378	* for sharing group of pages. The source address	432	* for sharing group of pages. The source address
379	* space area and any associated mapping is preserved.	433	* space area and any associated mapping is preserved.
380	*	434	*
381	* @param src_task Pointer of source task	435	* @param src_task Pointer of source task
382	* @param src_base Base address of the source address space area.	436	* @param src_base Base address of the source address space area.
383	* @param acc_size Expected size of the source area	437	* @param acc_size Expected size of the source area
384	* @param dst_base Target base address	438	* @param dst_base Target base address
385	*	439	*
386	* @return Zero on success or ENOENT if there is no such task or	440	* @return Zero on success or ENOENT if there is no such task or
387	* if there is no such address space area,	441	* if there is no such address space area,
388	* EPERM if there was a problem in accepting the area or	442	* EPERM if there was a problem in accepting the area or
389	* ENOMEM if there was a problem in allocating destination	443	* ENOMEM if there was a problem in allocating destination
390	* address space area.	444	* address space area.
391	*/	445	*/
392	int as_area_steal(task_t *src_task, __address src_base, size_t acc_size,	446	int as_area_steal(task_t *src_task, __address src_base, size_t acc_size,
393	__address dst_base)	447	__address dst_base)
394	{	448	{
395	ipl_t ipl;	449	ipl_t ipl;
396	count_t i;	450	count_t i;
397	as_t *src_as;	451	as_t *src_as;
398	int src_flags;	452	int src_flags;
399	size_t src_size;	453	size_t src_size;
400	as_area_t src_area, dst_area;	454	as_area_t src_area, dst_area;
401		455
402	ipl = interrupts_disable();	456	ipl = interrupts_disable();
403	spinlock_lock(&src_task->lock);	457	spinlock_lock(&src_task->lock);
404	src_as = src_task->as;	458	src_as = src_task->as;
405		459
406	mutex_lock(&src_as->lock);	460	mutex_lock(&src_as->lock);
407	src_area = find_area_and_lock(src_as, src_base);	461	src_area = find_area_and_lock(src_as, src_base);
408	if (!src_area) {	462	if (!src_area) {
409	/*	463	/*
410	* Could not find the source address space area.	464	* Could not find the source address space area.
411	*/	465	*/
412	spinlock_unlock(&src_task->lock);	466	spinlock_unlock(&src_task->lock);
413	mutex_unlock(&src_as->lock);	467	mutex_unlock(&src_as->lock);
414	interrupts_restore(ipl);	468	interrupts_restore(ipl);
415	return ENOENT;	469	return ENOENT;
416	}	470	}
417	src_size = src_area->pages * PAGE_SIZE;	471	src_size = src_area->pages * PAGE_SIZE;
418	src_flags = src_area->flags;	472	src_flags = src_area->flags;
419	mutex_unlock(&src_area->lock);	473	mutex_unlock(&src_area->lock);
420	mutex_unlock(&src_as->lock);	474	mutex_unlock(&src_as->lock);
421		475
422		-
423	if (src_size != acc_size) {	476	if (src_size != acc_size) {
424	spinlock_unlock(&src_task->lock);	477	spinlock_unlock(&src_task->lock);
425	interrupts_restore(ipl);	478	interrupts_restore(ipl);
426	return EPERM;	479	return EPERM;

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(root)/kernel/trunk/generic/src/mm/as.c – Rev 1387 → 1403