WebSVN – HelenOS – Diff – /trunk/kernel/generic/src/mm/frame.c


/*
 * Copyright (c) 2001-2005 Jakub Jermar
 * Copyright (c) 2005 Sergey Bondari
 * Copyright (c) 2009 Martin Decky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup genericmm
 * @{
 */
 
/**
 * @file
 * @brief Physical frame allocator.
 *
 * This file contains the physical frame allocator and memory zone management.
 * The frame allocator is built on top of the buddy allocator.
 *
 * @see buddy.c
 */
 
#include <arch/types.h>
#include <mm/frame.h>
#include <mm/as.h>
#include <panic.h>
#include <debug.h>
#include <adt/list.h>
#include <synch/mutex.h>
#include <synch/condvar.h>
#include <arch/asm.h>
#include <arch.h>
#include <print.h>
#include <align.h>
#include <mm/slab.h>
#include <bitops.h>
#include <macros.h>
#include <config.h>
 
zones_t zones;
 
/*
 * Synchronization primitives used to sleep when there is no memory
 * available.
 */
mutex_t mem_avail_mtx;
condvar_t mem_avail_cv;
count_t mem_avail_req = 0;  /**< Number of frames requested. */
count_t mem_avail_gen = 0;  /**< Generation counter. */
 
/********************/
/* Helper functions */
/********************/
 
static inline index_t frame_index(zone_t *zone, frame_t *frame)
{
    return (index_t) (frame - zone->frames);
}
 
static inline index_t frame_index_abs(zone_t *zone, frame_t *frame)
{
    return (index_t) (frame - zone->frames) + zone->base;
}
 
static inline bool frame_index_valid(zone_t *zone, index_t index)
{
    return (index < zone->count);
}
 
static inline index_t make_frame_index(zone_t *zone, frame_t *frame)
{
    return (frame - zone->frames);
}
 
/** Initialize frame structure.
 *
 * @param frame Frame structure to be initialized.
 *
 */
static void frame_initialize(frame_t *frame)
{
    frame->refcount = 1;
    frame->buddy_order = 0;
}
 
/*******************/
/* Zones functions */
/*******************/
 
/** Insert-sort zone into zones list.
 *
 * Assume interrupts are disabled and zones lock is
 * locked.
 *
 * @param base  Base frame of the newly inserted zone.
 * @param count Number of frames of the newly inserted zone.
 *
 * @return Zone number on success, -1 on error.
 *
 */
static count_t zones_insert_zone(pfn_t base, count_t count)
{
    if (zones.count + 1 == ZONES_MAX) {
        printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
        return (count_t) -1;
    }
   
    count_t i;
    for (i = 0; i < zones.count; i++) {
        /* Check for overlap */
        if (overlaps(base, count,
            zones.info[i].base, zones.info[i].count)) {
            printf("Zones overlap!\n");
            return (count_t) -1;
        }
        if (base < zones.info[i].base)
            break;
    }
   
    /* Move other zones up */
    count_t j;
    for (j = zones.count; j > i; j--) {
        zones.info[j] = zones.info[j - 1];
        zones.info[j].buddy_system->data =
            (void *) &zones.info[j - 1];
    }
   
    zones.count++;
   
    return i;
}
 
/** Get total available frames.
 *
 * Assume interrupts are disabled and zones lock is
 * locked.
 *
 * @return Total number of available frames.
 *
 */
#ifdef CONFIG_DEBUG
static count_t total_frames_free(void)
{
    count_t total = 0;
    count_t i;
    for (i = 0; i < zones.count; i++)
        total += zones.info[i].free_count;
   
    return total;
}
#endif
 
/** Find a zone with a given frames.
 *
 * Assume interrupts are disabled and zones lock is
 * locked.
 *
 * @param frame Frame number contained in zone.
 * @param count Number of frames to look for.
 * @param hint  Used as zone hint.
 *
 * @return Zone index or -1 if not found.
 *
 */
count_t find_zone(pfn_t frame, count_t count, count_t hint)
{
    if (hint >= zones.count)
        hint = 0;
   
    count_t i = hint;
    do {
        if ((zones.info[i].base <= frame)
            && (zones.info[i].base + zones.info[i].count >= frame + count))
            return i;
       
        i++;
        if (i >= zones.count)
            i = 0;
    } while (i != hint);
   
    return (count_t) -1;
}
 
/** @return True if zone can allocate specified order */
static bool zone_can_alloc(zone_t *zone, uint8_t order)
{
    return (zone_flags_available(zone->flags)
        && buddy_system_can_alloc(zone->buddy_system, order));
}
 
/** Find a zone that can allocate order frames.
 *
 * Assume interrupts are disabled and zones lock is
 * locked.
 *
 * @param order Size (2^order) of free space we are trying to find.
 * @param flags Required flags of the target zone.
 * @param hind  Preferred zone.
 *
 */
static count_t find_free_zone(uint8_t order, zone_flags_t flags, count_t hint)
{
    if (hint >= zones.count)
        hint = 0;
   
    count_t i = hint;
    do {
        /*
         * Check whether the zone meets the search criteria.
         */
        if ((zones.info[i].flags & flags) == flags) {
            /*
             * Check if the zone has 2^order frames area available.
             */
            if (zone_can_alloc(&zones.info[i], order))
                return i;
        }
       
        i++;
        if (i >= zones.count)
            i = 0;
    } while (i != hint);
   
    return (count_t) -1;
}
 
/**************************/
/* Buddy system functions */
/**************************/
 
/** Buddy system find_block implementation.
 *
 * Find block that is parent of current list.
 * That means go to lower addresses, until such block is found
 *
 * @param order Order of parent must be different then this
 *              parameter!!
 *
 */
static link_t *zone_buddy_find_block(buddy_system_t *buddy, link_t *child,
    uint8_t order)
{
    frame_t *frame = list_get_instance(child, frame_t, buddy_link);
    zone_t *zone = (zone_t *) buddy->data;
   
    index_t index = frame_index(zone, frame);
    do {
        if (zone->frames[index].buddy_order != order)
            return &zone->frames[index].buddy_link;
    } while (index-- > 0);
   
    return NULL;
}
 
/** Buddy system find_buddy implementation.
 *
 * @param buddy Buddy system.
 * @param block Block for which buddy should be found.
 *
 * @return Buddy for given block if found.
 *
 */
static link_t *zone_buddy_find_buddy(buddy_system_t *buddy, link_t *block)
{
    frame_t *frame = list_get_instance(block, frame_t, buddy_link);
    zone_t *zone = (zone_t *) buddy->data;
    ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
        frame->buddy_order));
   
    bool is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
 
 
 
   
    index_t index;
    if (is_left) {
        index = (frame_index(zone, frame)) +
            (1 << frame->buddy_order);
    } else {    /* is_right */
        index = (frame_index(zone, frame)) -
            (1 << frame->buddy_order);
    }
   
    if (frame_index_valid(zone, index)) {
        if ((zone->frames[index].buddy_order == frame->buddy_order) &&
            (zone->frames[index].refcount == 0)) {
            return &zone->frames[index].buddy_link;
        }
    }
   
    return NULL;
}
 
/** Buddy system bisect implementation.
 *
 * @param buddy Buddy system.
 * @param block Block to bisect.
 *
 * @return Right block.
 *
 */
static link_t *zone_buddy_bisect(buddy_system_t *buddy, link_t *block)
{
    frame_t *frame_l = list_get_instance(block, frame_t, buddy_link);
    frame_t *frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
   
    return &frame_r->buddy_link;
}
 
/** Buddy system coalesce implementation.
 *
 * @param buddy   Buddy system.
 * @param block_1 First block.
 * @param block_2 First block's buddy.
 *
 * @return Coalesced block (actually block that represents lower
 *         address).
 *
 */
static link_t *zone_buddy_coalesce(buddy_system_t *buddy, link_t *block_1,
    link_t *block_2)
{
    frame_t *frame1 = list_get_instance(block_1, frame_t, buddy_link);
    frame_t *frame2 = list_get_instance(block_2, frame_t, buddy_link);
   
    return ((frame1 < frame2) ? block_1 : block_2);
}
 
/** Buddy system set_order implementation.
 *
 * @param buddy Buddy system.
 * @param block Buddy system block.
 * @param order Order to set.
 *
 */
static void zone_buddy_set_order(buddy_system_t *buddy, link_t *block,
    uint8_t order)
{
    list_get_instance(block, frame_t, buddy_link)->buddy_order = order;
}
 
/** Buddy system get_order implementation.
 *
 * @param buddy Buddy system.
 * @param block Buddy system block.
 *
 * @return Order of block.
 *
 */
static uint8_t zone_buddy_get_order(buddy_system_t *buddy, link_t *block)
{
    return list_get_instance(block, frame_t, buddy_link)->buddy_order;
}
 
/** Buddy system mark_busy implementation.
 *
 * @param buddy Buddy system.
 * @param block Buddy system block.
 *
 */
static void zone_buddy_mark_busy(buddy_system_t *buddy, link_t * block)
{
    list_get_instance(block, frame_t, buddy_link)->refcount = 1;
}
 
/** Buddy system mark_available implementation.
 *
 * @param buddy Buddy system.
 * @param block Buddy system block.
 */
static void zone_buddy_mark_available(buddy_system_t *buddy, link_t *block)
{
    list_get_instance(block, frame_t, buddy_link)->refcount = 0;
}
 
static buddy_system_operations_t zone_buddy_system_operations = {
    .find_buddy = zone_buddy_find_buddy,
    .bisect = zone_buddy_bisect,
    .coalesce = zone_buddy_coalesce,
    .set_order = zone_buddy_set_order,
    .get_order = zone_buddy_get_order,
    .mark_busy = zone_buddy_mark_busy,
    .mark_available = zone_buddy_mark_available,
    .find_block = zone_buddy_find_block
};
 
/******************/
/* Zone functions */
/******************/
 
/** Allocate frame in particular zone.
 *
 * Assume zone is locked and is available for allocation.
 * Panics if allocation is impossible.
 *
 * @param zone  Zone to allocate from.
 * @param order Allocate exactly 2^order frames.
 *
 * @return Frame index in zone.
 *
 */
static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)
{
    ASSERT(zone_flags_available(zone->flags));
   
    /* Allocate frames from zone buddy system */
    link_t *link = buddy_system_alloc(zone->buddy_system, order);
   
    ASSERT(link);
   
    /* Update zone information. */
    zone->free_count -= (1 << order);
    zone->busy_count += (1 << order);
   
    /* Frame will be actually a first frame of the block. */
    frame_t *frame = list_get_instance(link, frame_t, buddy_link);
   
    /* Get frame address */
    return make_frame_index(zone, frame);
}
 
/** Free frame from zone.
 *
 * Assume zone is locked and is available for deallocation.
 *
 * @param zone      Pointer to zone from which the frame is to be freed.
 * @param frame_idx Frame index relative to zone.
 *
 */
static void zone_frame_free(zone_t *zone, index_t frame_idx)
{
    ASSERT(zone_flags_available(zone->flags));
   
    frame_t *frame = &zone->frames[frame_idx];
   
    /* Remember frame order */
    uint8_t order = frame->buddy_order;
   
    ASSERT(frame->refcount);
   
    if (!--frame->refcount) {
        buddy_system_free(zone->buddy_system, &frame->buddy_link);
       
        /* Update zone information. */
        zone->free_count += (1 << order);
        zone->busy_count -= (1 << order);
    }
}
 
/** Return frame from zone. */
static frame_t *zone_get_frame(zone_t *zone, index_t frame_idx)
{
    ASSERT(frame_idx < zone->count);
    return &zone->frames[frame_idx];
}
 
/** Mark frame in zone unavailable to allocation. */
static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)
{
    ASSERT(zone_flags_available(zone->flags));
   
    frame_t *frame = zone_get_frame(zone, frame_idx);
    if (frame->refcount)
        return;
   
    link_t *link __attribute__ ((unused));
   
    link = buddy_system_alloc_block(zone->buddy_system,
        &frame->buddy_link);
   
    ASSERT(link);
    zone->free_count--;
}
 
/** Merge two zones.
 *
 * Expect buddy to point to space at least zone_conf_size large.
 * Assume z1 & z2 are locked and compatible and zones lock is
 * locked.
 *
 * @param z1     First zone to merge.
 * @param z2     Second zone to merge.
 * @param old_z1 Original date of the first zone.
 * @param buddy  Merged zone buddy.
 *
 */
static void zone_merge_internal(count_t z1, count_t z2, zone_t *old_z1, buddy_system_t *buddy)
{
    ASSERT(zone_flags_available(zones.info[z1].flags));
    ASSERT(zone_flags_available(zones.info[z2].flags));
    ASSERT(zones.info[z1].flags == zones.info[z2].flags);
    ASSERT(zones.info[z1].base < zones.info[z2].base);
    ASSERT(!overlaps(zones.info[z1].base, zones.info[z1].count,
        zones.info[z2].base, zones.info[z2].count));
   
    /* Difference between zone bases */
    pfn_t base_diff = zones.info[z2].base - zones.info[z1].base;
   
    zones.info[z1].count = base_diff + zones.info[z2].count;
    zones.info[z1].free_count += zones.info[z2].free_count;
    zones.info[z1].busy_count += zones.info[z2].busy_count;
    zones.info[z1].buddy_system = buddy;
   
    uint8_t order = fnzb(zones.info[z1].count);
    buddy_system_create(zones.info[z1].buddy_system, order,
        &zone_buddy_system_operations, (void *) &zones.info[z1]);
   
    zones.info[z1].frames =
        (frame_t *) ((uint8_t *) zones.info[z1].buddy_system
        + buddy_conf_size(order));
   
    /* This marks all frames busy */
    count_t i;
    for (i = 0; i < zones.info[z1].count; i++)
        frame_initialize(&zones.info[z1].frames[i]);
   
    /* Copy frames from both zones to preserve full frame orders,
     * parents etc. Set all free frames with refcount = 0 to 1, because
     * we add all free frames to buddy allocator later again, clearing
     * order to 0. Don't set busy frames with refcount = 0, as they
     * will not be reallocated during merge and it would make later
     * problems with allocation/free.
     */
    for (i = 0; i < old_z1->count; i++)
        zones.info[z1].frames[i] = old_z1->frames[i];
   
    for (i = 0; i < zones.info[z2].count; i++)
        zones.info[z1].frames[base_diff + i]
            = zones.info[z2].frames[i];
   
    i = 0;
    while (i < zones.info[z1].count) {
        if (zones.info[z1].frames[i].refcount) {
            /* Skip busy frames */
            i += 1 << zones.info[z1].frames[i].buddy_order;
        } else {
            /* Free frames, set refcount = 1
             * (all free frames have refcount == 0, we need not
             * to check the order)
             */
            zones.info[z1].frames[i].refcount = 1;
            zones.info[z1].frames[i].buddy_order = 0;
            i++;
        }
    }
   
    /* Add free blocks from the original zone z1 */
    while (zone_can_alloc(old_z1, 0)) {
        /* Allocate from the original zone */
        pfn_t frame_idx = zone_frame_alloc(old_z1, 0);
       
        /* Free the frame from the merged zone */
        frame_t *frame = &zones.info[z1].frames[frame_idx];
        frame->refcount = 0;
        buddy_system_free(zones.info[z1].buddy_system, &frame->buddy_link);
    }
   
    /* Add free blocks from the original zone z2 */
    while (zone_can_alloc(&zones.info[z2], 0)) {
        /* Allocate from the original zone */
        pfn_t frame_idx = zone_frame_alloc(&zones.info[z2], 0);
       
        /* Free the frame from the merged zone */
        frame_t *frame = &zones.info[z1].frames[base_diff + frame_idx];
        frame->refcount = 0;
        buddy_system_free(zones.info[z1].buddy_system, &frame->buddy_link);
    }
}
 
/** Return old configuration frames into the zone.
 *
 * We have two cases:
 * - The configuration data is outside the zone
 *   -> do nothing (perhaps call frame_free?)
 * - The configuration data was created by zone_create
 *   or updated by reduce_region -> free every frame
 *
 * @param znum  The actual zone where freeing should occur.
 * @param pfn   Old zone configuration frame.
 * @param count Old zone frame count.
 *
 */
static void return_config_frames(count_t znum, pfn_t pfn, count_t count)
{
    ASSERT(zone_flags_available(zones.info[znum].flags));
   
    count_t cframes = SIZE2FRAMES(zone_conf_size(count));
   
    if ((pfn < zones.info[znum].base)
        || (pfn >= zones.info[znum].base + zones.info[znum].count))
        return;
   
    frame_t *frame __attribute__ ((unused));
 
    frame = &zones.info[znum].frames[pfn - zones.info[znum].base];
    ASSERT(!frame->buddy_order);
   
    count_t i;
    for (i = 0; i < cframes; i++) {
        zones.info[znum].busy_count++;
        zone_frame_free(&zones.info[znum],
            pfn - zones.info[znum].base + i);
    }
}
 
/** Reduce allocated block to count of order 0 frames.
 *
 * The allocated block needs 2^order frames. Reduce all frames
 * in the block to order 0 and free the unneeded frames. This means that
 * when freeing the previously allocated block starting with frame_idx,
 * you have to free every frame.
 *
 * @param znum      Zone.
 * @param frame_idx Index the first frame of the block.
 * @param count     Allocated frames in block.
 *
 */
static void zone_reduce_region(count_t znum, pfn_t frame_idx, count_t count)
{
    ASSERT(zone_flags_available(zones.info[znum].flags));
    ASSERT(frame_idx + count < zones.info[znum].count);
   
    uint8_t order = zones.info[znum].frames[frame_idx].buddy_order;
    ASSERT((count_t) (1 << order) >= count);
   
    /* Reduce all blocks to order 0 */
    count_t i;
    for (i = 0; i < (count_t) (1 << order); i++) {
        frame_t *frame = &zones.info[znum].frames[i + frame_idx];
        frame->buddy_order = 0;
        if (!frame->refcount)
            frame->refcount = 1;
        ASSERT(frame->refcount == 1);
    }
   
    /* Free unneeded frames */
    for (i = count; i < (count_t) (1 << order); i++)
        zone_frame_free(&zones.info[znum], i + frame_idx);
}
 
/** Merge zones z1 and z2.
 *
 * The merged zones must be 2 zones with no zone existing in between
 * (which means that z2 = z1 + 1). Both zones must be available zones
 * with the same flags.
 *
 * When you create a new zone, the frame allocator configuration does
 * not to be 2^order size. Once the allocator is running it is no longer
 * possible, merged configuration data occupies more space :-/
 *
 * The function uses
 *
 */
bool zone_merge(count_t z1, count_t z2)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    bool ret = true;
   
    /* We can join only 2 zones with none existing inbetween,
     * the zones have to be available and with the same
     * set of flags
     */
    if ((z1 >= zones.count) || (z2 >= zones.count)
        || (z2 - z1 != 1)
        || (!zone_flags_available(zones.info[z1].flags))
        || (!zone_flags_available(zones.info[z2].flags))
        || (zones.info[z1].flags != zones.info[z2].flags)) {
        ret = false;
        goto errout;
    }
   
    pfn_t cframes = SIZE2FRAMES(zone_conf_size(
        zones.info[z2].base - zones.info[z1].base
        + zones.info[z2].count));
   
    uint8_t order;
    if (cframes == 1)
        order = 0;
    else
        order = fnzb(cframes - 1) + 1;
   
    /* Allocate merged zone data inside one of the zones */
    pfn_t pfn;
    if (zone_can_alloc(&zones.info[z1], order)) {
        pfn = zones.info[z1].base + zone_frame_alloc(&zones.info[z1], order);
    } else if (zone_can_alloc(&zones.info[z2], order)) {
        pfn = zones.info[z2].base + zone_frame_alloc(&zones.info[z2], order);
    } else {
        ret = false;
        goto errout;
    }
   
    /* Preserve original data from z1 */
    zone_t old_z1 = zones.info[z1];
    old_z1.buddy_system->data = (void *) &old_z1;
   
    /* Do zone merging */
    buddy_system_t *buddy = (buddy_system_t *) PA2KA(PFN2ADDR(pfn));
    zone_merge_internal(z1, z2, &old_z1, buddy);
   
    /* Free unneeded config frames */
    zone_reduce_region(z1, pfn - zones.info[z1].base, cframes);
   
    /* Subtract zone information from busy frames */
    zones.info[z1].busy_count -= cframes;
   
    /* Free old zone information */
    return_config_frames(z1,
        ADDR2PFN(KA2PA((uintptr_t) old_z1.frames)), old_z1.count);
    return_config_frames(z1,
        ADDR2PFN(KA2PA((uintptr_t) zones.info[z2].frames)),
        zones.info[z2].count);
   
    /* Move zones down */
    count_t i;
    for (i = z2 + 1; i < zones.count; i++) {
        zones.info[i - 1] = zones.info[i];
        zones.info[i - 1].buddy_system->data =
            (void *) &zones.info[i - 1];
    }
   
    zones.count--;
   
errout:
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    return ret;
}
 
/** Merge all mergeable zones into one big zone.
 *
 * It is reasonable to do this on systems where
 * BIOS reports parts in chunks, so that we could
 * have 1 zone (it's faster).
 *
 */
void zone_merge_all(void)
{
    count_t i = 0;
    while (i < zones.count) {
        if (!zone_merge(i, i + 1))
            i++;
    }
}
 
/** Create new frame zone.
 *
 * @param zone  Zone to construct.
 * @param buddy Address of buddy system configuration information.
 * @param start Physical address of the first frame within the zone.
 * @param count Count of frames in zone.
 * @param flags Zone flags.
 *
 * @return Initialized zone.
 *
 */
static void zone_construct(zone_t *zone, buddy_system_t *buddy, pfn_t start, count_t count, zone_flags_t flags)
{
    zone->base = start;
    zone->count = count;
    zone->flags = flags;
    zone->free_count = count;
    zone->busy_count = 0;
    zone->buddy_system = buddy;
   
    if (zone_flags_available(flags)) {
        /*
         * Compute order for buddy system and initialize
         */
        uint8_t order = fnzb(count);
        buddy_system_create(zone->buddy_system, order,
            &zone_buddy_system_operations, (void *) zone);
       
        /* Allocate frames _after_ the confframe */
       
        /* Check sizes */
        zone->frames = (frame_t *) ((uint8_t *) zone->buddy_system +
            buddy_conf_size(order));
       
        count_t i;
        for (i = 0; i < count; i++)
            frame_initialize(&zone->frames[i]);
       
        /* Stuffing frames */
        for (i = 0; i < count; i++) {
            zone->frames[i].refcount = 0;
            buddy_system_free(zone->buddy_system, &zone->frames[i].buddy_link);
        }
    } else
        zone->frames = NULL;
}
 
/** Compute configuration data size for zone.
 *
 * @param count Size of zone in frames.
 *
 * @return Size of zone configuration info (in bytes).
 *
 */
uintptr_t zone_conf_size(count_t count)
{
    return (count * sizeof(frame_t) + buddy_conf_size(fnzb(count)));
}
 
/** Create and add zone to system.
 *
 * @param start     First frame number (absolute).
 * @param count     Size of zone in frames.
 * @param confframe Where configuration frames are supposed to be.
 *                  Automatically checks, that we will not disturb the
 *                  kernel and possibly init. If confframe is given
 *                  _outside_ this zone, it is expected, that the area is
 *                  already marked BUSY and big enough to contain
 *                  zone_conf_size() amount of data. If the confframe is
 *                  inside the area, the zone free frame information is
 *                  modified not to include it.
 *
 * @return Zone number or -1 on error.
 *
 */
count_t zone_create(pfn_t start, count_t count, pfn_t confframe, zone_flags_t flags)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    if (zone_flags_available(flags)) {  /* Create available zone */
        /* Theoretically we could have NULL here, practically make sure
         * nobody tries to do that. If some platform requires, remove
         * the assert
         */
        ASSERT(confframe != NULL);
       
        /* If confframe is supposed to be inside our zone, then make sure
         * it does not span kernel & init
         */
        count_t confcount = SIZE2FRAMES(zone_conf_size(count));
        if ((confframe >= start) && (confframe < start + count)) {
            for (; confframe < start + count; confframe++) {
                uintptr_t addr = PFN2ADDR(confframe);
                if (overlaps(addr, PFN2ADDR(confcount),
                    KA2PA(config.base), config.kernel_size))
                    continue;
               
                if (overlaps(addr, PFN2ADDR(confcount),
                    KA2PA(config.stack_base), config.stack_size))
                    continue;
               
                bool overlap = false;
                count_t i;
                for (i = 0; i < init.cnt; i++)
                    if (overlaps(addr, PFN2ADDR(confcount),
                        KA2PA(init.tasks[i].addr),
                        init.tasks[i].size)) {
                        overlap = true;
                        break;
                    }
                if (overlap)
                    continue;
               
                break;
            }
           
            if (confframe >= start + count)
                panic("Cannot find configuration data for zone.");
        }
       
        count_t znum = zones_insert_zone(start, count);
        if (znum == (count_t) -1) {
            spinlock_unlock(&zones.lock);
            interrupts_restore(ipl);
            return (count_t) -1;
        }
       
        buddy_system_t *buddy = (buddy_system_t *) PA2KA(PFN2ADDR(confframe));
        zone_construct(&zones.info[znum], buddy, start, count, flags);
       
        /* If confdata in zone, mark as unavailable */
        if ((confframe >= start) && (confframe < start + count)) {
            count_t i;
            for (i = confframe; i < confframe + confcount; i++)
                zone_mark_unavailable(&zones.info[znum],
                    i - zones.info[znum].base);
        }
       
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
       
        return znum;
    }
   
    /* Non-available zone */
    count_t znum = zones_insert_zone(start, count);
    if (znum == (count_t) -1) {
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
        return (count_t) -1;
    }
    zone_construct(&zones.info[znum], NULL, start, count, flags);
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    return znum;
}
 
/*******************/
/* Frame functions */
/*******************/
 
/** Set parent of frame. */
void frame_set_parent(pfn_t pfn, void *data, count_t hint)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    count_t znum = find_zone(pfn, 1, hint);
   
    ASSERT(znum != (count_t) -1);
   
    zone_get_frame(&zones.info[znum],
        pfn - zones.info[znum].base)->parent = data;
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
}
 
void *frame_get_parent(pfn_t pfn, count_t hint)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    count_t znum = find_zone(pfn, 1, hint);
   
    ASSERT(znum != (count_t) -1);
   
    void *res = zone_get_frame(&zones.info[znum],
        pfn - zones.info[znum].base)->parent;
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    return res;
}
 
/** Allocate power-of-two frames of physical memory.
 *
 * @param order Allocate exactly 2^order frames.
 * @param flags Flags for host zone selection and address processing.
 * @param pzone Preferred zone.
 *
 * @return Physical address of the allocated frame.
 *
 */
void *frame_alloc_generic(uint8_t order, frame_flags_t flags, count_t *pzone)
{
    count_t size = ((count_t) 1) << order;
    ipl_t ipl;
    count_t hint = pzone ? (*pzone) : 0;
   
loop:
    ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    /*
     * First, find suitable frame zone.
     */
    count_t znum = find_free_zone(order,
        FRAME_TO_ZONE_FLAGS(flags), hint);
   
    /* If no memory, reclaim some slab memory,
       if it does not help, reclaim all */
    if ((znum == (count_t) -1) && (!(flags & FRAME_NO_RECLAIM))) {
        count_t freed = slab_reclaim(0);
       
        if (freed > 0)
            znum = find_free_zone(order,
                FRAME_TO_ZONE_FLAGS(flags), hint);
       
        if (znum == (count_t) -1) {
            freed = slab_reclaim(SLAB_RECLAIM_ALL);
            if (freed > 0)
                znum = find_free_zone(order,
                    FRAME_TO_ZONE_FLAGS(flags), hint);
        }
    }
   
    if (znum == (count_t) -1) {
        if (flags & FRAME_ATOMIC) {
            spinlock_unlock(&zones.lock);
            interrupts_restore(ipl);
            return NULL;
        }
       
#ifdef CONFIG_DEBUG
        count_t avail = total_frames_free();
#endif
       
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
       
        /*
         * Sleep until some frames are available again.
         */
       
#ifdef CONFIG_DEBUG
        printf("Thread %" PRIu64 " waiting for %" PRIc " frames, "
            "%" PRIc " available.\n", THREAD->tid, size, avail);
#endif
       
        mutex_lock(&mem_avail_mtx);
       
        if (mem_avail_req > 0)
            mem_avail_req = min(mem_avail_req, size);
        else
            mem_avail_req = size;
        count_t gen = mem_avail_gen;
       
        while (gen == mem_avail_gen)
            condvar_wait(&mem_avail_cv, &mem_avail_mtx);
       
        mutex_unlock(&mem_avail_mtx);
       
#ifdef CONFIG_DEBUG
        printf("Thread %" PRIu64 " woken up.\n", THREAD->tid);
#endif
       
        goto loop;
    }
   
    pfn_t pfn = zone_frame_alloc(&zones.info[znum], order)
        + zones.info[znum].base;
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    if (pzone)
        *pzone = znum;
   
    if (flags & FRAME_KA)
        return (void *) PA2KA(PFN2ADDR(pfn));
   
    return (void *) PFN2ADDR(pfn);
}
 
/** Free a frame.
 *
 * Find respective frame structure for supplied physical frame address.
 * Decrement frame reference count. If it drops to zero, move the frame
 * structure to free list.
 *
 * @param frame Physical Address of of the frame to be freed.
 *
 */
void frame_free(uintptr_t frame)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    /*
     * First, find host frame zone for addr.
     */
    pfn_t pfn = ADDR2PFN(frame);
    count_t znum = find_zone(pfn, 1, NULL);
   
    ASSERT(znum != (count_t) -1);
   
    zone_frame_free(&zones.info[znum], pfn - zones.info[znum].base);
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    /*
     * Signal that some memory has been freed.
     */
    mutex_lock(&mem_avail_mtx);
    if (mem_avail_req > 0)
        mem_avail_req--;
   
    if (mem_avail_req == 0) {
        mem_avail_gen++;
        condvar_broadcast(&mem_avail_cv);
    }
    mutex_unlock(&mem_avail_mtx);
}
 
/** Add reference to frame.
 *
 * Find respective frame structure for supplied PFN and
 * increment frame reference count.
 *
 * @param pfn Frame number of the frame to be freed.
 *
 */
void frame_reference_add(pfn_t pfn)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    /*
     * First, find host frame zone for addr.
     */
    count_t znum = find_zone(pfn, 1, NULL);
   
    ASSERT(znum != (count_t) -1);
   
    zones.info[znum].frames[pfn - zones.info[znum].base].refcount++;
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
}
 
/** Mark given range unavailable in frame zones. */
void frame_mark_unavailable(pfn_t start, count_t count)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    count_t i;
    for (i = 0; i < count; i++) {
        count_t znum = find_zone(start + i, 1, 0);
        if (znum == (count_t) -1)  /* PFN not found */
            continue;
       
        zone_mark_unavailable(&zones.info[znum],
            start + i - zones.info[znum].base);
    }
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
}
 
/** Initialize physical memory management. */
void frame_init(void)
{
    if (config.cpu_active == 1) {
        zones.count = 0;
        spinlock_initialize(&zones.lock, "zones.lock");
        mutex_initialize(&mem_avail_mtx, MUTEX_ACTIVE);
        condvar_initialize(&mem_avail_cv);
    }
   
    /* Tell the architecture to create some memory */
    frame_arch_init();
    if (config.cpu_active == 1) {
        frame_mark_unavailable(ADDR2PFN(KA2PA(config.base)),
            SIZE2FRAMES(config.kernel_size));
        frame_mark_unavailable(ADDR2PFN(KA2PA(config.stack_base)),
            SIZE2FRAMES(config.stack_size));
       
        count_t i;
        for (i = 0; i < init.cnt; i++) {
            pfn_t pfn = ADDR2PFN(KA2PA(init.tasks[i].addr));
            frame_mark_unavailable(pfn,
                SIZE2FRAMES(init.tasks[i].size));
        }
       
        if (ballocs.size)
            frame_mark_unavailable(ADDR2PFN(KA2PA(ballocs.base)),
                SIZE2FRAMES(ballocs.size));
       
        /* Black list first frame, as allocating NULL would
         * fail in some places
         */
        frame_mark_unavailable(0, 1);
    }
}
 
/** Return total size of all zones. */
uint64_t zone_total_size(void)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    uint64_t total = 0;
    count_t i;
    for (i = 0; i < zones.count; i++)
        total += (uint64_t) FRAMES2SIZE(zones.info[i].count);
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    return total;
}
 
/** Prints list of zones. */
void zone_print_list(void)
{
#ifdef __32_BITS__
    printf("#  base address frames       flags    free frames  busy frames\n");
    printf("-- ------------ ------------ -------- ------------ ------------\n");
#endif
 
#ifdef __64_BITS__
    printf("#  base address          frames      flags    free frames  busy frames\n");
    printf("-- -------------------- ------------ -------- ------------ ------------\n");
#endif
   
    /*
     * Because printing may require allocation of memory, we may not hold
     * the frame allocator locks when printing zone statistics.  Therefore,
     * we simply gather the statistics under the protection of the locks and
     * print the statistics when the locks have been released.
     *
     * When someone adds/removes zones while we are printing the statistics,
     * we may end up with inaccurate output (e.g. a zone being skipped from
     * the listing).
     */
   
    count_t i;
    for (i = 0;; i++) {
        ipl_t ipl = interrupts_disable();
        spinlock_lock(&zones.lock);
       
        if (i >= zones.count) {
            spinlock_unlock(&zones.lock);
            interrupts_restore(ipl);
            break;
        }
       
        uintptr_t base = PFN2ADDR(zones.info[i].base);
        count_t count = zones.info[i].count;
        zone_flags_t flags = zones.info[i].flags;
        count_t free_count = zones.info[i].free_count;
        count_t busy_count = zones.info[i].busy_count;
       
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
       
        bool available = zone_flags_available(flags);
       
        printf("%-2" PRIc, i);
       
#ifdef __32_BITS__
        printf("   %10p", base);
#endif
       
#ifdef __64_BITS__
        printf("   %18p", base);
#endif
       
        printf(" %12" PRIc " %c%c%c      ", count,
            available ? 'A' : ' ',
            (flags & ZONE_RESERVED) ? 'R' : ' ',
            (flags & ZONE_FIRMWARE) ? 'F' : ' ');
       
        if (available)
            printf("%12" PRIc " %12" PRIc,
                free_count, busy_count);
       
        printf("\n");
    }
}
 
/** Prints zone details.
 *
 * @param num Zone base address or zone number.
 *
 */
void zone_print_one(count_t num)
{
    ipl_t ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
    count_t znum = (count_t) -1;
   
    count_t i;
    for (i = 0; i < zones.count; i++) {
        if ((i == num) || (PFN2ADDR(zones.info[i].base) == num)) {
            znum = i;
            break;
        }
    }
   
    if (znum == (count_t) -1) {
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
        printf("Zone not found.\n");
        return;
    }
   
    uintptr_t base = PFN2ADDR(zones.info[i].base);
    zone_flags_t flags = zones.info[i].flags;
    count_t count = zones.info[i].count;
    count_t free_count = zones.info[i].free_count;
    count_t busy_count = zones.info[i].busy_count;
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    bool available = zone_flags_available(flags);
   
    printf("Zone number:       %" PRIc "\n", znum);
    printf("Zone base address: %p\n", base);
    printf("Zone size:         %" PRIc " frames (%" PRIs " KiB)\n", count,
        SIZE2KB(FRAMES2SIZE(count)));
    printf("Zone flags:        %c%c%c\n",
        available ? 'A' : ' ',
        (flags & ZONE_RESERVED) ? 'R' : ' ',
        (flags & ZONE_FIRMWARE) ? 'F' : ' ');
   
    if (available) {
        printf("Allocated space:   %" PRIc " frames (%" PRIs " KiB)\n",
            busy_count, SIZE2KB(FRAMES2SIZE(busy_count)));
        printf("Available space:   %" PRIc " frames (%" PRIs " KiB)\n",
            free_count, SIZE2KB(FRAMES2SIZE(free_count)));
    }
}
 
/** @}
 */
 

Rev 3973	Rev 4048
1	/*	1	/*
2	* Copyright (c) 2001-2005 Jakub Jermar	2	* Copyright (c) 2001-2005 Jakub Jermar
3	* Copyright (c) 2005 Sergey Bondari	3	* Copyright (c) 2005 Sergey Bondari
4	* Copyright (c) 2009 Martin Decky	4	* Copyright (c) 2009 Martin Decky
5	* All rights reserved.	5	* All rights reserved.
6	*	6	*
7	* Redistribution and use in source and binary forms, with or without	7	* Redistribution and use in source and binary forms, with or without
8	* modification, are permitted provided that the following conditions	8	* modification, are permitted provided that the following conditions
9	* are met:	9	* are met:
10	*	10	*
11	* - Redistributions of source code must retain the above copyright	11	* - Redistributions of source code must retain the above copyright
12	* notice, this list of conditions and the following disclaimer.	12	* notice, this list of conditions and the following disclaimer.
13	* - Redistributions in binary form must reproduce the above copyright	13	* - Redistributions in binary form must reproduce the above copyright
14	* notice, this list of conditions and the following disclaimer in the	14	* notice, this list of conditions and the following disclaimer in the
15	* documentation and/or other materials provided with the distribution.	15	* documentation and/or other materials provided with the distribution.
16	* - The name of the author may not be used to endorse or promote products	16	* - The name of the author may not be used to endorse or promote products
17	* derived from this software without specific prior written permission.	17	* derived from this software without specific prior written permission.
18	*	18	*
19	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	19	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	20	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	21	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	22	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	23	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	24	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	25	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	26	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	27	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	28	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29	*/	29	*/
30		30
31	/** @addtogroup genericmm	31	/** @addtogroup genericmm
32	* @{	32	* @{
33	*/	33	*/
34		34
35	/**	35	/**
36	* @file	36	* @file
37	* @brief Physical frame allocator.	37	* @brief Physical frame allocator.
38	*	38	*
39	* This file contains the physical frame allocator and memory zone management.	39	* This file contains the physical frame allocator and memory zone management.
40	* The frame allocator is built on top of the buddy allocator.	40	* The frame allocator is built on top of the buddy allocator.
41	*	41	*
42	* @see buddy.c	42	* @see buddy.c
43	*/	43	*/
44		44
45	#include <arch/types.h>	45	#include <arch/types.h>
46	#include <mm/frame.h>	46	#include <mm/frame.h>
47	#include <mm/as.h>	47	#include <mm/as.h>
48	#include <panic.h>	48	#include <panic.h>
49	#include <debug.h>	49	#include <debug.h>
50	#include <adt/list.h>	50	#include <adt/list.h>
51	#include <synch/mutex.h>	51	#include <synch/mutex.h>
52	#include <synch/condvar.h>	52	#include <synch/condvar.h>
53	#include <arch/asm.h>	53	#include <arch/asm.h>
54	#include <arch.h>	54	#include <arch.h>
55	#include <print.h>	55	#include <print.h>
56	#include <align.h>	56	#include <align.h>
57	#include <mm/slab.h>	57	#include <mm/slab.h>
58	#include <bitops.h>	58	#include <bitops.h>
59	#include <macros.h>	59	#include <macros.h>
60	#include <config.h>	60	#include <config.h>
61		61
62	zones_t zones;	62	zones_t zones;
63		63
64	/*	64	/*
65	* Synchronization primitives used to sleep when there is no memory	65	* Synchronization primitives used to sleep when there is no memory
66	* available.	66	* available.
67	*/	67	*/
68	mutex_t mem_avail_mtx;	68	mutex_t mem_avail_mtx;
69	condvar_t mem_avail_cv;	69	condvar_t mem_avail_cv;
70	count_t mem_avail_req = 0; /*< Number of frames requested. /	70	count_t mem_avail_req = 0; /*< Number of frames requested. /
71	count_t mem_avail_gen = 0; /*< Generation counter. /	71	count_t mem_avail_gen = 0; /*< Generation counter. /
72		72
73	/********************/	73	/********************/
74	/* Helper functions */	74	/* Helper functions */
75	/********************/	75	/********************/
76		76
77	static inline index_t frame_index(zone_t zone, frame_t frame)	77	static inline index_t frame_index(zone_t zone, frame_t frame)
78	{	78	{
79	return (index_t) (frame - zone->frames);	79	return (index_t) (frame - zone->frames);
80	}	80	}
81		81
82	static inline index_t frame_index_abs(zone_t zone, frame_t frame)	82	static inline index_t frame_index_abs(zone_t zone, frame_t frame)
83	{	83	{
84	return (index_t) (frame - zone->frames) + zone->base;	84	return (index_t) (frame - zone->frames) + zone->base;
85	}	85	}
86		86
87	static inline bool frame_index_valid(zone_t *zone, index_t index)	87	static inline bool frame_index_valid(zone_t *zone, index_t index)
88	{	88	{
89	return (index < zone->count);	89	return (index < zone->count);
90	}	90	}
91		91
92	static inline index_t make_frame_index(zone_t zone, frame_t frame)	92	static inline index_t make_frame_index(zone_t zone, frame_t frame)
93	{	93	{
94	return (frame - zone->frames);	94	return (frame - zone->frames);
95	}	95	}
96		96
97	/** Initialize frame structure.	97	/** Initialize frame structure.
98	*	98	*
99	* @param frame Frame structure to be initialized.	99	* @param frame Frame structure to be initialized.
100	*	100	*
101	*/	101	*/
102	static void frame_initialize(frame_t *frame)	102	static void frame_initialize(frame_t *frame)
103	{	103	{
104	frame->refcount = 1;	104	frame->refcount = 1;
105	frame->buddy_order = 0;	105	frame->buddy_order = 0;
106	}	106	}
107		107
108	/*******************/	108	/*******************/
109	/* Zones functions */	109	/* Zones functions */
110	/*******************/	110	/*******************/
111		111
112	/** Insert-sort zone into zones list.	112	/** Insert-sort zone into zones list.
113	*	113	*
114	* Assume interrupts are disabled and zones lock is	114	* Assume interrupts are disabled and zones lock is
115	* locked.	115	* locked.
116	*	116	*
117	* @param base Base frame of the newly inserted zone.	117	* @param base Base frame of the newly inserted zone.
118	* @param count Number of frames of the newly inserted zone.	118	* @param count Number of frames of the newly inserted zone.
119	*	119	*
120	* @return Zone number on success, -1 on error.	120	* @return Zone number on success, -1 on error.
121	*	121	*
122	*/	122	*/
123	static count_t zones_insert_zone(pfn_t base, count_t count)	123	static count_t zones_insert_zone(pfn_t base, count_t count)
124	{	124	{
125	if (zones.count + 1 == ZONES_MAX) {	125	if (zones.count + 1 == ZONES_MAX) {
126	printf("Maximum zone count %u exceeded!\n", ZONES_MAX);	126	printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
127	return (count_t) -1;	127	return (count_t) -1;
128	}	128	}
129		129
130	count_t i;	130	count_t i;
131	for (i = 0; i < zones.count; i++) {	131	for (i = 0; i < zones.count; i++) {
132	/* Check for overlap */	132	/* Check for overlap */
133	if (overlaps(base, count,	133	if (overlaps(base, count,
134	zones.info[i].base, zones.info[i].count)) {	134	zones.info[i].base, zones.info[i].count)) {
135	printf("Zones overlap!\n");	135	printf("Zones overlap!\n");
136	return (count_t) -1;	136	return (count_t) -1;
137	}	137	}
138	if (base < zones.info[i].base)	138	if (base < zones.info[i].base)
139	break;	139	break;
140	}	140	}
141		141
142	/* Move other zones up */	142	/* Move other zones up */
143	count_t j;	143	count_t j;
144	for (j = zones.count; j > i; j--) {	144	for (j = zones.count; j > i; j--) {
145	zones.info[j] = zones.info[j - 1];	145	zones.info[j] = zones.info[j - 1];
146	zones.info[j].buddy_system->data =	146	zones.info[j].buddy_system->data =
147	(void *) &zones.info[j - 1];	147	(void *) &zones.info[j - 1];
148	}	148	}
149		149
150	zones.count++;	150	zones.count++;
151		151
152	return i;	152	return i;
153	}	153	}
154		154
155	/** Get total available frames.	155	/** Get total available frames.
156	*	156	*
157	* Assume interrupts are disabled and zones lock is	157	* Assume interrupts are disabled and zones lock is
158	* locked.	158	* locked.
159	*	159	*
160	* @return Total number of available frames.	160	* @return Total number of available frames.
161	*	161	*
162	*/	162	*/
-		163	#ifdef CONFIG_DEBUG
163	static count_t total_frames_free(void)	164	static count_t total_frames_free(void)
164	{	165	{
165	count_t total = 0;	166	count_t total = 0;
166	count_t i;	167	count_t i;
167	for (i = 0; i < zones.count; i++)	168	for (i = 0; i < zones.count; i++)
168	total += zones.info[i].free_count;	169	total += zones.info[i].free_count;
169		170
170	return total;	171	return total;
171	}	172	}
-		173	#endif
172		174
173	/** Find a zone with a given frames.	175	/** Find a zone with a given frames.
174	*	176	*
175	* Assume interrupts are disabled and zones lock is	177	* Assume interrupts are disabled and zones lock is
176	* locked.	178	* locked.
177	*	179	*
178	* @param frame Frame number contained in zone.	180	* @param frame Frame number contained in zone.
179	* @param count Number of frames to look for.	181	* @param count Number of frames to look for.
180	* @param hint Used as zone hint.	182	* @param hint Used as zone hint.
181	*	183	*
182	* @return Zone index or -1 if not found.	184	* @return Zone index or -1 if not found.
183	*	185	*
184	*/	186	*/
185	count_t find_zone(pfn_t frame, count_t count, count_t hint)	187	count_t find_zone(pfn_t frame, count_t count, count_t hint)
186	{	188	{
187	if (hint >= zones.count)	189	if (hint >= zones.count)
188	hint = 0;	190	hint = 0;
189		191
190	count_t i = hint;	192	count_t i = hint;
191	do {	193	do {
192	if ((zones.info[i].base <= frame)	194	if ((zones.info[i].base <= frame)
193	&& (zones.info[i].base + zones.info[i].count >= frame + count))	195	&& (zones.info[i].base + zones.info[i].count >= frame + count))
194	return i;	196	return i;
195		197
196	i++;	198	i++;
197	if (i >= zones.count)	199	if (i >= zones.count)
198	i = 0;	200	i = 0;
199	} while (i != hint);	201	} while (i != hint);
200		202
201	return (count_t) -1;	203	return (count_t) -1;
202	}	204	}
203		205
204	/** @return True if zone can allocate specified order */	206	/** @return True if zone can allocate specified order */
205	static bool zone_can_alloc(zone_t *zone, uint8_t order)	207	static bool zone_can_alloc(zone_t *zone, uint8_t order)
206	{	208	{
207	return (zone_flags_available(zone->flags)	209	return (zone_flags_available(zone->flags)
208	&& buddy_system_can_alloc(zone->buddy_system, order));	210	&& buddy_system_can_alloc(zone->buddy_system, order));
209	}	211	}
210		212
211	/** Find a zone that can allocate order frames.	213	/** Find a zone that can allocate order frames.
212	*	214	*
213	* Assume interrupts are disabled and zones lock is	215	* Assume interrupts are disabled and zones lock is
214	* locked.	216	* locked.
215	*	217	*
216	* @param order Size (2^order) of free space we are trying to find.	218	* @param order Size (2^order) of free space we are trying to find.
217	* @param flags Required flags of the target zone.	219	* @param flags Required flags of the target zone.
218	* @param hind Preferred zone.	220	* @param hind Preferred zone.
219	*	221	*
220	*/	222	*/
221	static count_t find_free_zone(uint8_t order, zone_flags_t flags, count_t hint)	223	static count_t find_free_zone(uint8_t order, zone_flags_t flags, count_t hint)
222	{	224	{
223	if (hint >= zones.count)	225	if (hint >= zones.count)
224	hint = 0;	226	hint = 0;
225		227
226	count_t i = hint;	228	count_t i = hint;
227	do {	229	do {
228	/*	230	/*
229	* Check whether the zone meets the search criteria.	231	* Check whether the zone meets the search criteria.
230	*/	232	*/
231	if ((zones.info[i].flags & flags) == flags) {	233	if ((zones.info[i].flags & flags) == flags) {
232	/*	234	/*
233	* Check if the zone has 2^order frames area available.	235	* Check if the zone has 2^order frames area available.
234	*/	236	*/
235	if (zone_can_alloc(&zones.info[i], order))	237	if (zone_can_alloc(&zones.info[i], order))
236	return i;	238	return i;
237	}	239	}
238		240
239	i++;	241	i++;
240	if (i >= zones.count)	242	if (i >= zones.count)
241	i = 0;	243	i = 0;
242	} while (i != hint);	244	} while (i != hint);
243		245
244	return (count_t) -1;	246	return (count_t) -1;
245	}	247	}
246		248
247	/**************************/	249	/**************************/
248	/* Buddy system functions */	250	/* Buddy system functions */
249	/**************************/	251	/**************************/
250		252
251	/** Buddy system find_block implementation.	253	/** Buddy system find_block implementation.
252	*	254	*
253	* Find block that is parent of current list.	255	* Find block that is parent of current list.
254	* That means go to lower addresses, until such block is found	256	* That means go to lower addresses, until such block is found
255	*	257	*
256	* @param order Order of parent must be different then this	258	* @param order Order of parent must be different then this
257	* parameter!!	259	* parameter!!
258	*	260	*
259	*/	261	*/
260	static link_t zone_buddy_find_block(buddy_system_t buddy, link_t *child,	262	static link_t zone_buddy_find_block(buddy_system_t buddy, link_t *child,
261	uint8_t order)	263	uint8_t order)
262	{	264	{
263	frame_t *frame = list_get_instance(child, frame_t, buddy_link);	265	frame_t *frame = list_get_instance(child, frame_t, buddy_link);
264	zone_t zone = (zone_t ) buddy->data;	266	zone_t zone = (zone_t ) buddy->data;
265		267
266	index_t index = frame_index(zone, frame);	268	index_t index = frame_index(zone, frame);
267	do {	269	do {
268	if (zone->frames[index].buddy_order != order)	270	if (zone->frames[index].buddy_order != order)
269	return &zone->frames[index].buddy_link;	271	return &zone->frames[index].buddy_link;
270	} while (index-- > 0);	272	} while (index-- > 0);
271		273
272	return NULL;	274	return NULL;
273	}	275	}
274		276
275	/** Buddy system find_buddy implementation.	277	/** Buddy system find_buddy implementation.
276	*	278	*
277	* @param buddy Buddy system.	279	* @param buddy Buddy system.
278	* @param block Block for which buddy should be found.	280	* @param block Block for which buddy should be found.
279	*	281	*
280	* @return Buddy for given block if found.	282	* @return Buddy for given block if found.
281	*	283	*
282	*/	284	*/
283	static link_t zone_buddy_find_buddy(buddy_system_t buddy, link_t *block)	285	static link_t zone_buddy_find_buddy(buddy_system_t buddy, link_t *block)
284	{	286	{
285	frame_t *frame = list_get_instance(block, frame_t, buddy_link);	287	frame_t *frame = list_get_instance(block, frame_t, buddy_link);
286	zone_t zone = (zone_t ) buddy->data;	288	zone_t zone = (zone_t ) buddy->data;
287	ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),	289	ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
288	frame->buddy_order));	290	frame->buddy_order));
289		291
290	bool is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);	292	bool is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
291	bool is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);	-
292		-
293	ASSERT(is_left ^ is_right);	-
294		293
295	index_t index;	294	index_t index;
296	if (is_left) {	295	if (is_left) {
297	index = (frame_index(zone, frame)) +	296	index = (frame_index(zone, frame)) +
298	(1 << frame->buddy_order);	297	(1 << frame->buddy_order);
299	} else { /* if (is_right) */	298	} else { /* is_right */
300	index = (frame_index(zone, frame)) -	299	index = (frame_index(zone, frame)) -
301	(1 << frame->buddy_order);	300	(1 << frame->buddy_order);
302	}	301	}
303		302
304	if (frame_index_valid(zone, index)) {	303	if (frame_index_valid(zone, index)) {
305	if ((zone->frames[index].buddy_order == frame->buddy_order) &&	304	if ((zone->frames[index].buddy_order == frame->buddy_order) &&
306	(zone->frames[index].refcount == 0)) {	305	(zone->frames[index].refcount == 0)) {
307	return &zone->frames[index].buddy_link;	306	return &zone->frames[index].buddy_link;
308	}	307	}
309	}	308	}
310		309
311	return NULL;	310	return NULL;
312	}	311	}
313		312
314	/** Buddy system bisect implementation.	313	/** Buddy system bisect implementation.
315	*	314	*
316	* @param buddy Buddy system.	315	* @param buddy Buddy system.
317	* @param block Block to bisect.	316	* @param block Block to bisect.
318	*	317	*
319	* @return Right block.	318	* @return Right block.
320	*	319	*
321	*/	320	*/
322	static link_t zone_buddy_bisect(buddy_system_t buddy, link_t *block)	321	static link_t zone_buddy_bisect(buddy_system_t buddy, link_t *block)
323	{	322	{
324	frame_t *frame_l = list_get_instance(block, frame_t, buddy_link);	323	frame_t *frame_l = list_get_instance(block, frame_t, buddy_link);
325	frame_t *frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));	324	frame_t *frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
326		325
327	return &frame_r->buddy_link;	326	return &frame_r->buddy_link;
328	}	327	}
329		328
330	/** Buddy system coalesce implementation.	329	/** Buddy system coalesce implementation.
331	*	330	*
332	* @param buddy Buddy system.	331	* @param buddy Buddy system.
333	* @param block_1 First block.	332	* @param block_1 First block.
334	* @param block_2 First block's buddy.	333	* @param block_2 First block's buddy.
335	*	334	*
336	* @return Coalesced block (actually block that represents lower	335	* @return Coalesced block (actually block that represents lower
337	* address).	336	* address).
338	*	337	*
339	*/	338	*/
340	static link_t zone_buddy_coalesce(buddy_system_t buddy, link_t *block_1,	339	static link_t zone_buddy_coalesce(buddy_system_t buddy, link_t *block_1,
341	link_t *block_2)	340	link_t *block_2)
342	{	341	{
343	frame_t *frame1 = list_get_instance(block_1, frame_t, buddy_link);	342	frame_t *frame1 = list_get_instance(block_1, frame_t, buddy_link);
344	frame_t *frame2 = list_get_instance(block_2, frame_t, buddy_link);	343	frame_t *frame2 = list_get_instance(block_2, frame_t, buddy_link);
345		344
346	return ((frame1 < frame2) ? block_1 : block_2);	345	return ((frame1 < frame2) ? block_1 : block_2);
347	}	346	}
348		347
349	/** Buddy system set_order implementation.	348	/** Buddy system set_order implementation.
350	*	349	*
351	* @param buddy Buddy system.	350	* @param buddy Buddy system.
352	* @param block Buddy system block.	351	* @param block Buddy system block.
353	* @param order Order to set.	352	* @param order Order to set.
354	*	353	*
355	*/	354	*/
356	static void zone_buddy_set_order(buddy_system_t buddy, link_t block,	355	static void zone_buddy_set_order(buddy_system_t buddy, link_t block,
357	uint8_t order)	356	uint8_t order)
358	{	357	{
359	list_get_instance(block, frame_t, buddy_link)->buddy_order = order;	358	list_get_instance(block, frame_t, buddy_link)->buddy_order = order;
360	}	359	}
361		360
362	/** Buddy system get_order implementation.	361	/** Buddy system get_order implementation.
363	*	362	*
364	* @param buddy Buddy system.	363	* @param buddy Buddy system.
365	* @param block Buddy system block.	364	* @param block Buddy system block.
366	*	365	*
367	* @return Order of block.	366	* @return Order of block.
368	*	367	*
369	*/	368	*/
370	static uint8_t zone_buddy_get_order(buddy_system_t buddy, link_t block)	369	static uint8_t zone_buddy_get_order(buddy_system_t buddy, link_t block)
371	{	370	{
372	return list_get_instance(block, frame_t, buddy_link)->buddy_order;	371	return list_get_instance(block, frame_t, buddy_link)->buddy_order;
373	}	372	}
374		373
375	/** Buddy system mark_busy implementation.	374	/** Buddy system mark_busy implementation.
376	*	375	*
377	* @param buddy Buddy system.	376	* @param buddy Buddy system.
378	* @param block Buddy system block.	377	* @param block Buddy system block.
379	*	378	*
380	*/	379	*/
381	static void zone_buddy_mark_busy(buddy_system_t buddy, link_t block)	380	static void zone_buddy_mark_busy(buddy_system_t buddy, link_t block)
382	{	381	{
383	list_get_instance(block, frame_t, buddy_link)->refcount = 1;	382	list_get_instance(block, frame_t, buddy_link)->refcount = 1;
384	}	383	}
385		384
386	/** Buddy system mark_available implementation.	385	/** Buddy system mark_available implementation.
387	*	386	*
388	* @param buddy Buddy system.	387	* @param buddy Buddy system.
389	* @param block Buddy system block.	388	* @param block Buddy system block.
390	*/	389	*/
391	static void zone_buddy_mark_available(buddy_system_t buddy, link_t block)	390	static void zone_buddy_mark_available(buddy_system_t buddy, link_t block)
392	{	391	{
393	list_get_instance(block, frame_t, buddy_link)->refcount = 0;	392	list_get_instance(block, frame_t, buddy_link)->refcount = 0;
394	}	393	}
395		394
396	static buddy_system_operations_t zone_buddy_system_operations = {	395	static buddy_system_operations_t zone_buddy_system_operations = {
397	.find_buddy = zone_buddy_find_buddy,	396	.find_buddy = zone_buddy_find_buddy,
398	.bisect = zone_buddy_bisect,	397	.bisect = zone_buddy_bisect,
399	.coalesce = zone_buddy_coalesce,	398	.coalesce = zone_buddy_coalesce,
400	.set_order = zone_buddy_set_order,	399	.set_order = zone_buddy_set_order,
401	.get_order = zone_buddy_get_order,	400	.get_order = zone_buddy_get_order,
402	.mark_busy = zone_buddy_mark_busy,	401	.mark_busy = zone_buddy_mark_busy,
403	.mark_available = zone_buddy_mark_available,	402	.mark_available = zone_buddy_mark_available,
404	.find_block = zone_buddy_find_block	403	.find_block = zone_buddy_find_block
405	};	404	};
406		405
407	/******************/	406	/******************/
408	/* Zone functions */	407	/* Zone functions */
409	/******************/	408	/******************/
410		409
411	/** Allocate frame in particular zone.	410	/** Allocate frame in particular zone.
412	*	411	*
413	* Assume zone is locked and is available for allocation.	412	* Assume zone is locked and is available for allocation.
414	* Panics if allocation is impossible.	413	* Panics if allocation is impossible.
415	*	414	*
416	* @param zone Zone to allocate from.	415	* @param zone Zone to allocate from.
417	* @param order Allocate exactly 2^order frames.	416	* @param order Allocate exactly 2^order frames.
418	*	417	*
419	* @return Frame index in zone.	418	* @return Frame index in zone.
420	*	419	*
421	*/	420	*/
422	static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)	421	static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)
423	{	422	{
424	ASSERT(zone_flags_available(zone->flags));	423	ASSERT(zone_flags_available(zone->flags));
425		424
426	/* Allocate frames from zone buddy system */	425	/* Allocate frames from zone buddy system */
427	link_t *link = buddy_system_alloc(zone->buddy_system, order);	426	link_t *link = buddy_system_alloc(zone->buddy_system, order);
428		427
429	ASSERT(link);	428	ASSERT(link);
430		429
431	/* Update zone information. */	430	/* Update zone information. */
432	zone->free_count -= (1 << order);	431	zone->free_count -= (1 << order);
433	zone->busy_count += (1 << order);	432	zone->busy_count += (1 << order);
434		433
435	/* Frame will be actually a first frame of the block. */	434	/* Frame will be actually a first frame of the block. */
436	frame_t *frame = list_get_instance(link, frame_t, buddy_link);	435	frame_t *frame = list_get_instance(link, frame_t, buddy_link);
437		436
438	/* Get frame address */	437	/* Get frame address */
439	return make_frame_index(zone, frame);	438	return make_frame_index(zone, frame);
440	}	439	}
441		440
442	/** Free frame from zone.	441	/** Free frame from zone.
443	*	442	*
444	* Assume zone is locked and is available for deallocation.	443	* Assume zone is locked and is available for deallocation.
445	*	444	*
446	* @param zone Pointer to zone from which the frame is to be freed.	445	* @param zone Pointer to zone from which the frame is to be freed.
447	* @param frame_idx Frame index relative to zone.	446	* @param frame_idx Frame index relative to zone.
448	*	447	*
449	*/	448	*/
450	static void zone_frame_free(zone_t *zone, index_t frame_idx)	449	static void zone_frame_free(zone_t *zone, index_t frame_idx)
451	{	450	{
452	ASSERT(zone_flags_available(zone->flags));	451	ASSERT(zone_flags_available(zone->flags));
453		452
454	frame_t *frame = &zone->frames[frame_idx];	453	frame_t *frame = &zone->frames[frame_idx];
455		454
456	/* Remember frame order */	455	/* Remember frame order */
457	uint8_t order = frame->buddy_order;	456	uint8_t order = frame->buddy_order;
458		457
459	ASSERT(frame->refcount);	458	ASSERT(frame->refcount);
460		459
461	if (!--frame->refcount) {	460	if (!--frame->refcount) {
462	buddy_system_free(zone->buddy_system, &frame->buddy_link);	461	buddy_system_free(zone->buddy_system, &frame->buddy_link);
463		462
464	/* Update zone information. */	463	/* Update zone information. */
465	zone->free_count += (1 << order);	464	zone->free_count += (1 << order);
466	zone->busy_count -= (1 << order);	465	zone->busy_count -= (1 << order);
467	}	466	}
468	}	467	}
469		468
470	/** Return frame from zone. */	469	/** Return frame from zone. */
471	static frame_t zone_get_frame(zone_t zone, index_t frame_idx)	470	static frame_t zone_get_frame(zone_t zone, index_t frame_idx)
472	{	471	{
473	ASSERT(frame_idx < zone->count);	472	ASSERT(frame_idx < zone->count);
474	return &zone->frames[frame_idx];	473	return &zone->frames[frame_idx];
475	}	474	}
476		475
477	/** Mark frame in zone unavailable to allocation. */	476	/** Mark frame in zone unavailable to allocation. */
478	static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)	477	static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)
479	{	478	{
480	ASSERT(zone_flags_available(zone->flags));	479	ASSERT(zone_flags_available(zone->flags));
481		480
482	frame_t *frame = zone_get_frame(zone, frame_idx);	481	frame_t *frame = zone_get_frame(zone, frame_idx);
483	if (frame->refcount)	482	if (frame->refcount)
484	return;	483	return;
485		484
-		485	link_t *link __attribute__ ((unused));
-		486
486	link_t *link = buddy_system_alloc_block(zone->buddy_system,	487	link = buddy_system_alloc_block(zone->buddy_system,
487	&frame->buddy_link);	488	&frame->buddy_link);
488		489
489	ASSERT(link);	490	ASSERT(link);
490	zone->free_count--;	491	zone->free_count--;
491	}	492	}
492		493
493	/** Merge two zones.	494	/** Merge two zones.
494	*	495	*
495	* Expect buddy to point to space at least zone_conf_size large.	496	* Expect buddy to point to space at least zone_conf_size large.
496	* Assume z1 & z2 are locked and compatible and zones lock is	497	* Assume z1 & z2 are locked and compatible and zones lock is

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(root)/trunk/kernel/generic/src/mm/frame.c @ 3240 – Rev 3973 → 4048