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


/*
 * Copyright (c) 2001-2005 Jakub Jermar
 * Copyright (c) 2005 Sergey Bondari
 * 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
 */
 
/*
 * Locking order
 *
 * In order to access particular zone, the process must first lock
 * the zones.lock, then lock the zone and then unlock the zones.lock.
 * This insures, that we can fiddle with the zones in runtime without
 * affecting the processes.
 *
 */
 
#include <arch/types.h>
#include <mm/frame.h>
#include <mm/as.h>
#include <panic.h>
#include <debug.h>
#include <adt/list.h>
#include <synch/spinlock.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>
 
typedef struct {
    count_t refcount;   /**< tracking of shared frames  */
    uint8_t buddy_order;    /**< buddy system block order */
    link_t buddy_link;  /**< link to the next free block inside one
                     order */
    void *parent;           /**< If allocated by slab, this points there */
} frame_t;
 
typedef struct {
    SPINLOCK_DECLARE(lock); /**< this lock protects everything below */
    pfn_t base;     /**< frame_no of the first frame in the frames
                     array */
    count_t count;          /**< Size of zone */
 
    frame_t *frames;    /**< array of frame_t structures in this
                     zone */
    count_t free_count; /**< number of free frame_t structures */
    count_t busy_count; /**< number of busy frame_t structures */
   
    buddy_system_t *buddy_system; /**< buddy system for the zone */
    int flags;
} zone_t;
 
/*
 * The zoneinfo.lock must be locked when accessing zoneinfo structure.
 * Some of the attributes in zone_t structures are 'read-only'
 */
 
typedef struct {
    SPINLOCK_DECLARE(lock);
    unsigned int count;
    zone_t *info[ZONES_MAX];
} zones_t;
 
static zones_t zones;
 
/*
 * Synchronization primitives used to sleep when there is no memory
 * available.
 */
mutex_t mem_avail_mtx;
condvar_t mem_avail_cv;
unsigned long mem_avail_frames = 0; /**< Number of available frames. */
unsigned long 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 int frame_index_valid(zone_t *zone, index_t index)
{
    return (index < zone->count);
}
 
/** Compute pfn_t from frame_t pointer & zone pointer */
static 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;
}
 
/**********************/
/* Zoneinfo functions */
/**********************/
 
/** Insert-sort zone into zones list.
 *
 * @param newzone   New zone to be inserted into zone list.
 * @return      Zone number on success, -1 on error.
 */
static int zones_add_zone(zone_t *newzone)
{
    unsigned int i, j;
    ipl_t ipl;
    zone_t *z;
 
    ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    /* Try to merge */
    if (zones.count + 1 == ZONES_MAX) {
        printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
        return -1;
    }
   
    for (i = 0; i < zones.count; i++) {
        /* Check for overflow */
        z = zones.info[i];
        if (overlaps(newzone->base, newzone->count, z->base,
            z->count)) {
            printf("Zones overlap!\n");
            return -1;
        }
        if (newzone->base < z->base)
            break;
    }
   
    /* Move other zones up */
    for (j = i; j < zones.count; j++)
        zones.info[j + 1] = zones.info[j];
   
    zones.info[i] = newzone;
    zones.count++;
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
 
    return i;
}
 
/** Try to find a zone where can we find the frame.
 *
 * Assume interrupts are disabled.
 *
 * @param frame     Frame number contained in zone.
 * @param pzone     If not null, it is used as zone hint. Zone index is
 *          filled into the variable on success.
 * @return      Pointer to locked zone containing frame.
 */
static zone_t *find_zone_and_lock(pfn_t frame, unsigned int *pzone)
{
    unsigned int i;
    unsigned int hint = pzone ? *pzone : 0;
    zone_t *z;
   
    spinlock_lock(&zones.lock);
 
    if (hint >= zones.count)
        hint = 0;
   
    i = hint;
    do {
        z = zones.info[i];
        spinlock_lock(&z->lock);
        if (z->base <= frame && z->base + z->count > frame) {
            /* Unlock the global lock */
            spinlock_unlock(&zones.lock);
            if (pzone)
                *pzone = i;
            return z;
        }
        spinlock_unlock(&z->lock);
 
        i++;
        if (i >= zones.count)
            i = 0;
    } while (i != hint);
 
    spinlock_unlock(&zones.lock);
    return NULL;
}
 
/** @return True if zone can allocate specified order */
static int zone_can_alloc(zone_t *z, uint8_t order)
{
    return buddy_system_can_alloc(z->buddy_system, order);
}
 
/** Find and lock zone that can allocate order frames.
 *
 * Assume interrupts are disabled.
 *
 * @param order     Size (2^order) of free space we are trying to find.
 * @param flags     Required flags of the target zone.
 * @param pzone     Pointer to preferred zone or NULL, on return contains
 *          zone number.
 */
static zone_t *
find_free_zone_and_lock(uint8_t order, int flags, unsigned int *pzone)
{
    unsigned int i;
    zone_t *z;
    unsigned int hint = pzone ? *pzone : 0;
   
    /* Mask off flags that are not applicable. */
    flags &= FRAME_LOW_4_GiB;
 
    spinlock_lock(&zones.lock);
    if (hint >= zones.count)
        hint = 0;
    i = hint;
    do {
        z = zones.info[i];
       
        spinlock_lock(&z->lock);
 
        /*
         * Check whether the zone meets the search criteria.
         */
        if ((z->flags & flags) == flags) {
            /*
             * Check if the zone has 2^order frames area available.
             */
            if (zone_can_alloc(z, order)) {
                spinlock_unlock(&zones.lock);
                if (pzone)
                    *pzone = i;
                return z;
            }
        }
        spinlock_unlock(&z->lock);
        if (++i >= zones.count)
            i = 0;
    } while (i != hint);
    spinlock_unlock(&zones.lock);
    return NULL;
}
 
/**************************/
/* 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 *b, link_t *child,
    uint8_t order)
{
    frame_t *frame;
    zone_t *zone;
    index_t index;
   
    frame = list_get_instance(child, frame_t, buddy_link);
    zone = (zone_t *) b->data;
 
    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 b     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 *b, link_t *block)
{
    frame_t *frame;
    zone_t *zone;
    index_t index;
    bool is_left, is_right;
 
    frame = list_get_instance(block, frame_t, buddy_link);
    zone = (zone_t *) b->data;
    ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
        frame->buddy_order));
   
    is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
    is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
 
    ASSERT(is_left ^ is_right);
    if (is_left) {
        index = (frame_index(zone, frame)) +
            (1 << frame->buddy_order);
    } else {    /* if (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 b     Buddy system.
 * @param block     Block to bisect.
 *
 * @return      Right block.
 */
static link_t *zone_buddy_bisect(buddy_system_t *b, link_t *block)
{
    frame_t *frame_l, *frame_r;
 
    frame_l = list_get_instance(block, frame_t, buddy_link);
    frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
   
    return &frame_r->buddy_link;
}
 
/** Buddy system coalesce implementation.
 *
 * @param b     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 *b, link_t *block_1,
    link_t *block_2)
{
    frame_t *frame1, *frame2;
   
    frame1 = list_get_instance(block_1, frame_t, buddy_link);
    frame2 = list_get_instance(block_2, frame_t, buddy_link);
   
    return frame1 < frame2 ? block_1 : block_2;
}
 
/** Buddy system set_order implementation.
 *
 * @param b     Buddy system.
 * @param block     Buddy system block.
 * @param order     Order to set.
 */
static void zone_buddy_set_order(buddy_system_t *b, link_t *block,
    uint8_t order)
{
    frame_t *frame;
    frame = list_get_instance(block, frame_t, buddy_link);
    frame->buddy_order = order;
}
 
/** Buddy system get_order implementation.
 *
 * @param b     Buddy system.
 * @param block     Buddy system block.
 *
 * @return      Order of block.
 */
static uint8_t zone_buddy_get_order(buddy_system_t *b, link_t *block)
{
    frame_t *frame;
    frame = list_get_instance(block, frame_t, buddy_link);
    return frame->buddy_order;
}
 
/** Buddy system mark_busy implementation.
 *
 * @param b     Buddy system.
 * @param block     Buddy system block.
 */
static void zone_buddy_mark_busy(buddy_system_t *b, link_t * block)
{
    frame_t * frame;
 
    frame = list_get_instance(block, frame_t, buddy_link);
    frame->refcount = 1;
}
 
/** Buddy system mark_available implementation.
 *
 * @param b     Buddy system.
 * @param block     Buddy system block.
 */
static void zone_buddy_mark_available(buddy_system_t *b, link_t *block)
{
    frame_t *frame;
    frame = list_get_instance(block, frame_t, buddy_link);
    frame->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.
 * 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)
{
    pfn_t v;
    link_t *tmp;
    frame_t *frame;
 
    /* Allocate frames from zone buddy system */
    tmp = buddy_system_alloc(zone->buddy_system, order);
   
    ASSERT(tmp);
   
    /* Update zone information. */
    zone->free_count -= (1 << order);
    zone->busy_count += (1 << order);
 
    /* Frame will be actually a first frame of the block. */
    frame = list_get_instance(tmp, frame_t, buddy_link);
   
    /* get frame address */
    v = make_frame_index(zone, frame);
    return v;
}
 
/** Free frame from zone.
 *
 * Assume zone is locked.
 *
 * @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)
{
    frame_t *frame;
    uint8_t order;
 
    frame = &zone->frames[frame_idx];
   
    /* remember frame order */
    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)
{
    frame_t *frame;
    link_t *link;
 
    frame = zone_get_frame(zone, frame_idx);
    if (frame->refcount)
        return;
    link = buddy_system_alloc_block(zone->buddy_system,
        &frame->buddy_link);
    ASSERT(link);
    zone->free_count--;
 
    mutex_lock(&mem_avail_mtx);
    mem_avail_frames--;
    mutex_unlock(&mem_avail_mtx);
}
 
/** Join two zones.
 *
 * Expect zone_t *z to point to space at least zone_conf_size large.
 *
 * Assume z1 & z2 are locked.
 *
 * @param z     Target zone structure pointer.
 * @param z1        Zone to merge.
 * @param z2        Zone to merge.
 */
static void _zone_merge(zone_t *z, zone_t *z1, zone_t *z2)
{
    uint8_t max_order;
    unsigned int i;
    int z2idx;
    pfn_t frame_idx;
    frame_t *frame;
 
    ASSERT(!overlaps(z1->base, z1->count, z2->base, z2->count));
    ASSERT(z1->base < z2->base);
 
    spinlock_initialize(&z->lock, "zone_lock");
    z->base = z1->base;
    z->count = z2->base + z2->count - z1->base;
    z->flags = z1->flags & z2->flags;
 
    z->free_count = z1->free_count + z2->free_count;
    z->busy_count = z1->busy_count + z2->busy_count;
   
    max_order = fnzb(z->count);
 
    z->buddy_system = (buddy_system_t *) &z[1];
    buddy_system_create(z->buddy_system, max_order,
        &zone_buddy_system_operations, (void *) z);
 
    z->frames = (frame_t *)((uint8_t *) z->buddy_system +
        buddy_conf_size(max_order));
    for (i = 0; i < z->count; i++) {
        /* This marks all frames busy */
        frame_initialize(&z->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, clear
     * 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 < z1->count; i++)
        z->frames[i] = z1->frames[i];
    for (i = 0; i < z2->count; i++) {
        z2idx = i + (z2->base - z1->base);
        z->frames[z2idx] = z2->frames[i];
    }
    i = 0;
    while (i < z->count) {
        if (z->frames[i].refcount) {
            /* skip busy frames */
            i += 1 << z->frames[i].buddy_order;
        } else { /* Free frames, set refcount=1 */
            /* All free frames have refcount=0, we need not
             * to check the order */
            z->frames[i].refcount = 1;
            z->frames[i].buddy_order = 0;
            i++;
        }
    }
    /* Add free blocks from the 2 original zones */
    while (zone_can_alloc(z1, 0)) {
        frame_idx = zone_frame_alloc(z1, 0);
        frame = &z->frames[frame_idx];
        frame->refcount = 0;
        buddy_system_free(z->buddy_system, &frame->buddy_link);
    }
    while (zone_can_alloc(z2, 0)) {
        frame_idx = zone_frame_alloc(z2, 0);
        frame = &z->frames[frame_idx + (z2->base - z1->base)];
        frame->refcount = 0;
        buddy_system_free(z->buddy_system, &frame->buddy_link);
    }
}
 
/** Return old configuration frames into the zone.
 *
 * We have several cases
 * - the conf. data is outside of zone -> exit, shall we call frame_free??
 * - the conf. data was created by zone_create or
 *   updated with reduce_region -> free every frame
 *
 * @param newzone   The actual zone where freeing should occur.
 * @param oldzone   Pointer to old zone configuration data that should
 *          be freed from new zone.
 */
static void return_config_frames(zone_t *newzone, zone_t *oldzone)
{
    pfn_t pfn;
    frame_t *frame;
    count_t cframes;
    unsigned int i;
 
    pfn = ADDR2PFN((uintptr_t)KA2PA(oldzone));
    cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
   
    if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
        return;
 
    frame = &newzone->frames[pfn - newzone->base];
    ASSERT(!frame->buddy_order);
 
    for (i = 0; i < cframes; i++) {
        newzone->busy_count++;
        zone_frame_free(newzone, pfn+i-newzone->base);
    }
}
 
/** Reduce allocated block to count of order 0 frames.
 *
 * The allocated block need 2^order frames of space. Reduce all frames
 * in 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 zone
 * @param frame_idx     Index to block.
 * @param count         Allocated space in block.
 */
static void zone_reduce_region(zone_t *zone, pfn_t frame_idx, count_t count)
{
    count_t i;
    uint8_t order;
    frame_t *frame;
   
    ASSERT(frame_idx + count < zone->count);
 
    order = zone->frames[frame_idx].buddy_order;
    ASSERT((count_t) (1 << order) >= count);
 
    /* Reduce all blocks to order 0 */
    for (i = 0; i < (count_t) (1 << order); i++) {
        frame = &zone->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(zone, i + frame_idx);
    }
}
 
/** Merge zones z1 and z2.
 *
 * - the zones must be 2 zones with no zone existing in between,
 *   which means that z2 = z1+1
 *
 * - 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 :-/
 */
void zone_merge(unsigned int z1, unsigned int z2)
{
    ipl_t ipl;
    zone_t *zone1, *zone2, *newzone;
    unsigned int cframes;
    uint8_t order;
    unsigned int i;
    pfn_t pfn;
 
    ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
 
    if ((z1 >= zones.count) || (z2 >= zones.count))
        goto errout;
    /* We can join only 2 zones with none existing inbetween */
    if (z2 - z1 != 1)
        goto errout;
 
    zone1 = zones.info[z1];
    zone2 = zones.info[z2];
    spinlock_lock(&zone1->lock);
    spinlock_lock(&zone2->lock);
 
    cframes = SIZE2FRAMES(zone_conf_size(zone2->base + zone2->count -
        zone1->base));
    if (cframes == 1)
        order = 0;
    else
        order = fnzb(cframes - 1) + 1;
 
    /* Allocate zonedata inside one of the zones */
    if (zone_can_alloc(zone1, order))
        pfn = zone1->base + zone_frame_alloc(zone1, order);
    else if (zone_can_alloc(zone2, order))
        pfn = zone2->base + zone_frame_alloc(zone2, order);
    else
        goto errout2;
 
    newzone = (zone_t *) PA2KA(PFN2ADDR(pfn));
 
    _zone_merge(newzone, zone1, zone2);
 
    /* Free unneeded config frames */
    zone_reduce_region(newzone, pfn - newzone->base,  cframes);
    /* Subtract zone information from busy frames */
    newzone->busy_count -= cframes;
 
    /* Replace existing zones in zoneinfo list */
    zones.info[z1] = newzone;
    for (i = z2 + 1; i < zones.count; i++)
        zones.info[i - 1] = zones.info[i];
    zones.count--;
 
    /* Free old zone information */
    return_config_frames(newzone, zone1);
    return_config_frames(newzone, zone2);
errout2:
    /* Nobody is allowed to enter to zone, so we are safe
     * to touch the spinlocks last time */
    spinlock_unlock(&zone1->lock);
    spinlock_unlock(&zone2->lock);
errout:
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
}
 
/** Merge all zones into one big zone.
 *
 * It is reasonable to do this on systems whose bios reports parts in chunks,
 * so that we could have 1 zone (it's faster).
 */
void zone_merge_all(void)
{
    int count = zones.count;
 
    while (zones.count > 1 && --count) {
        zone_merge(0, 1);
        break;
    }
}
 
/** Create new frame zone.
 *
 * @param start     Physical address of the first frame within the zone.
 * @param count     Count of frames in zone.
 * @param z     Address of configuration information of zone.
 * @param flags     Zone flags.
 *
 * @return      Initialized zone.
 */
static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
{
    unsigned int i;
    uint8_t max_order;
 
    spinlock_initialize(&z->lock, "zone_lock");
    z->base = start;
    z->count = count;
 
    /* Mask off flags that are calculated automatically. */
    flags &= ~FRAME_LOW_4_GiB;
    /* Determine calculated flags. */
    if (z->base + count < (1ULL << (32 - FRAME_WIDTH))) /* 4 GiB */
        flags |= FRAME_LOW_4_GiB;
 
    z->flags = flags;
 
    z->free_count = count;
    z->busy_count = 0;
 
    /*
     * Compute order for buddy system, initialize
     */
    max_order = fnzb(count);
    z->buddy_system = (buddy_system_t *)&z[1];
   
    buddy_system_create(z->buddy_system, max_order,
        &zone_buddy_system_operations, (void *) z);
   
    /* Allocate frames _after_ the conframe */
    /* Check sizes */
    z->frames = (frame_t *)((uint8_t *) z->buddy_system +
        buddy_conf_size(max_order));
    for (i = 0; i < count; i++) {
        frame_initialize(&z->frames[i]);
    }
   
    /* Stuffing frames */
    for (i = 0; i < count; i++) {
        z->frames[i].refcount = 0;
        buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
    }
}
 
/** 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)
{
    int size = sizeof(zone_t) + count * sizeof(frame_t);
    int max_order;
 
    max_order = fnzb(count);
    size += buddy_conf_size(max_order);
    return size;
}
 
/** 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.
 */
int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
{
    zone_t *z;
    uintptr_t addr;
    count_t confcount;
    unsigned int i;
    int znum;
 
    /* Theoretically we could have here 0, practically make sure
     * nobody tries to do that. If some platform requires, remove
     * the assert
     */
    ASSERT(confframe);
    /* If conframe is supposed to be inside our zone, then make sure
     * it does not span kernel & init
     */
    confcount = SIZE2FRAMES(zone_conf_size(count));
    if (confframe >= start && confframe < start + count) {
        for (; confframe < start + count; confframe++) {
            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.");
    }
 
    z = (zone_t *) PA2KA(PFN2ADDR(confframe));
    zone_construct(start, count, z, flags);
    znum = zones_add_zone(z);
    if (znum == -1)
        return -1;
 
    mutex_lock(&mem_avail_mtx);
    mem_avail_frames += count;
    mutex_unlock(&mem_avail_mtx);
 
    /* If confdata in zone, mark as unavailable */
    if (confframe >= start && confframe < start + count)
        for (i = confframe; i < confframe + confcount; i++) {
            zone_mark_unavailable(z, i - z->base);
        }
   
    return znum;
}
 
/***************************************/
/* Frame functions */
 
/** Set parent of frame. */
void frame_set_parent(pfn_t pfn, void *data, unsigned int hint)
{
    zone_t *zone = find_zone_and_lock(pfn, &hint);
 
    ASSERT(zone);
 
    zone_get_frame(zone, pfn - zone->base)->parent = data;
    spinlock_unlock(&zone->lock);
}
 
void *frame_get_parent(pfn_t pfn, unsigned int hint)
{
    zone_t *zone = find_zone_and_lock(pfn, &hint);
    void *res;
 
    ASSERT(zone);
    res = zone_get_frame(zone, pfn - zone->base)->parent;
   
    spinlock_unlock(&zone->lock);
    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, int flags, unsigned int *pzone)
{
    ipl_t ipl;
    int freed;
    pfn_t v;
    zone_t *zone;
    unsigned long gen = 0;
   
loop:
    ipl = interrupts_disable();
   
    /*
     * First, find suitable frame zone.
     */
    zone = find_free_zone_and_lock(order, flags, pzone);
   
    /* If no memory, reclaim some slab memory,
       if it does not help, reclaim all */
    if (!zone && !(flags & FRAME_NO_RECLAIM)) {
        freed = slab_reclaim(0);
        if (freed)
            zone = find_free_zone_and_lock(order, flags, pzone);
        if (!zone) {
            freed = slab_reclaim(SLAB_RECLAIM_ALL);
            if (freed)
                zone = find_free_zone_and_lock(order, flags,
                    pzone);
        }
    }
    if (!zone) {
        /*
         * Sleep until some frames are available again.
         */
        if (flags & FRAME_ATOMIC) {
            interrupts_restore(ipl);
            return 0;
        }
       
#ifdef CONFIG_DEBUG
        unsigned long avail;
 
        mutex_lock(&mem_avail_mtx);
        avail = mem_avail_frames;
        mutex_unlock(&mem_avail_mtx);
 
        printf("Thread %" PRIu64 " waiting for %u frames, "
            "%u available.\n", THREAD->tid, 1ULL << order, avail);
#endif
 
        mutex_lock(&mem_avail_mtx);
        while ((mem_avail_frames < (1ULL << order)) ||
            gen == mem_avail_gen)
            condvar_wait(&mem_avail_cv, &mem_avail_mtx);
        gen = mem_avail_gen;
        mutex_unlock(&mem_avail_mtx);
 
#ifdef CONFIG_DEBUG
        mutex_lock(&mem_avail_mtx);
        avail = mem_avail_frames;
        mutex_unlock(&mem_avail_mtx);
 
        printf("Thread %" PRIu64 " woken up, %u frames available.\n",
            THREAD->tid, avail);
#endif
 
        interrupts_restore(ipl);
        goto loop;
    }
   
    v = zone_frame_alloc(zone, order);
    v += zone->base;
 
    spinlock_unlock(&zone->lock);
   
    mutex_lock(&mem_avail_mtx);
    mem_avail_frames -= (1ULL << order);
    mutex_unlock(&mem_avail_mtx);
 
    interrupts_restore(ipl);
 
    if (flags & FRAME_KA)
        return (void *)PA2KA(PFN2ADDR(v));
    return (void *)PFN2ADDR(v);
}
 
/** 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;
    zone_t *zone;
    pfn_t pfn = ADDR2PFN(frame);
 
    ipl = interrupts_disable();
 
    /*
     * First, find host frame zone for addr.
     */
    zone = find_zone_and_lock(pfn, NULL);
    ASSERT(zone);
   
    zone_frame_free(zone, pfn - zone->base);
   
    spinlock_unlock(&zone->lock);
   
    /*
     * Signal that some memory has been freed.
     */
    mutex_lock(&mem_avail_mtx);
    mem_avail_frames++;
    mem_avail_gen++;
    condvar_broadcast(&mem_avail_cv);
    mutex_unlock(&mem_avail_mtx);
 
    interrupts_restore(ipl);
}
 
/** 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;
    zone_t *zone;
    frame_t *frame;
 
    ipl = interrupts_disable();
   
    /*
     * First, find host frame zone for addr.
     */
    zone = find_zone_and_lock(pfn, NULL);
    ASSERT(zone);
   
    frame = &zone->frames[pfn - zone->base];
    frame->refcount++;
   
    spinlock_unlock(&zone->lock);
    interrupts_restore(ipl);
}
 
/** Mark given range unavailable in frame zones. */
void frame_mark_unavailable(pfn_t start, count_t count)
{
    unsigned int i;
    zone_t *zone;
    unsigned int prefzone = 0;
   
    for (i = 0; i < count; i++) {
        zone = find_zone_and_lock(start + i, &prefzone);
        if (!zone) /* PFN not found */
            continue;
        zone_mark_unavailable(zone, start + i - zone->base);
 
        spinlock_unlock(&zone->lock);
    }
}
 
/** 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)
{
    zone_t *zone = NULL;
    unsigned int i;
    ipl_t ipl;
    uint64_t total = 0;
 
    ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
   
    for (i = 0; i < zones.count; i++) {
        zone = zones.info[i];
        spinlock_lock(&zone->lock);
        total += (uint64_t) FRAMES2SIZE(zone->count);
        spinlock_unlock(&zone->lock);
    }
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
   
    return total;
}
 
/** Prints list of zones. */
void zone_print_list(void)
{
    zone_t *zone = NULL;
    unsigned int i;
    ipl_t ipl;
 
#ifdef __32_BITS__  
    printf("#  base address free frames  busy frames\n");
    printf("-- ------------ ------------ ------------\n");
#endif
 
#ifdef __64_BITS__
    printf("#  base address         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).
     */
 
    for (i = 0; ; i++) {
        uintptr_t base;
        count_t free_count;
        count_t busy_count;
 
        ipl = interrupts_disable();
        spinlock_lock(&zones.lock);
       
        if (i >= zones.count) {
            spinlock_unlock(&zones.lock);
            interrupts_restore(ipl);
            break;
        }
 
        zone = zones.info[i];
        spinlock_lock(&zone->lock);
 
        base = PFN2ADDR(zone->base);
        free_count = zone->free_count;
        busy_count = zone->busy_count;
 
        spinlock_unlock(&zone->lock);
       
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
 
#ifdef __32_BITS__
        printf("%-2u   %10p %12" PRIc " %12" PRIc "\n", i, base,
            free_count, busy_count);
#endif
 
#ifdef __64_BITS__
        printf("%-2u   %18p %12" PRIc " %12" PRIc "\n", i, base,
            free_count, busy_count);
#endif
       
    }
}
 
/** Prints zone details.
 *
 * @param num       Zone base address or zone number.
 */
void zone_print_one(unsigned int num)
{
    zone_t *zone = NULL;
    ipl_t ipl;
    unsigned int i;
    uintptr_t base;
    count_t count;
    count_t busy_count;
    count_t free_count;
 
    ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
 
    for (i = 0; i < zones.count; i++) {
        if ((i == num) || (PFN2ADDR(zones.info[i]->base) == num)) {
            zone = zones.info[i];
            break;
        }
    }
    if (!zone) {
        spinlock_unlock(&zones.lock);
        interrupts_restore(ipl);
        printf("Zone not found.\n");
        return;
    }
   
    spinlock_lock(&zone->lock);
    base = PFN2ADDR(zone->base);
    count = zone->count;
    busy_count = zone->busy_count;
    free_count = zone->free_count;
    spinlock_unlock(&zone->lock);
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
 
    printf("Zone base address: %p\n", base);
    printf("Zone size: %" PRIc " frames (%" PRIs " KiB)\n", count,
        SIZE2KB(FRAMES2SIZE(count)));
    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 3207	Rev 3208
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	* All rights reserved.	4	* All rights reserved.
5	*	5	*
6	* Redistribution and use in source and binary forms, with or without	6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions	7	* modification, are permitted provided that the following conditions
8	* are met:	8	* are met:
9	*	9	*
10	* - Redistributions of source code must retain the above copyright	10	* - Redistributions of source code must retain the above copyright
11	* notice, this list of conditions and the following disclaimer.	11	* notice, this list of conditions and the following disclaimer.
12	* - Redistributions in binary form must reproduce the above copyright	12	* - Redistributions in binary form must reproduce the above copyright
13	* notice, this list of conditions and the following disclaimer in the	13	* notice, this list of conditions and the following disclaimer in the
14	* documentation and/or other materials provided with the distribution.	14	* documentation and/or other materials provided with the distribution.
15	* - The name of the author may not be used to endorse or promote products	15	* - The name of the author may not be used to endorse or promote products
16	* derived from this software without specific prior written permission.	16	* derived from this software without specific prior written permission.
17	*	17	*
18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28	*/	28	*/
29		29
30	/** @addtogroup genericmm	30	/** @addtogroup genericmm
31	* @{	31	* @{
32	*/	32	*/
33		33
34	/**	34	/**
35	* @file	35	* @file
36	* @brief Physical frame allocator.	36	* @brief Physical frame allocator.
37	*	37	*
38	* This file contains the physical frame allocator and memory zone management.	38	* This file contains the physical frame allocator and memory zone management.
39	* The frame allocator is built on top of the buddy allocator.	39	* The frame allocator is built on top of the buddy allocator.
40	*	40	*
41	* @see buddy.c	41	* @see buddy.c
42	*/	42	*/
43		43
44	/*	44	/*
45	* Locking order	45	* Locking order
46	*	46	*
47	* In order to access particular zone, the process must first lock	47	* In order to access particular zone, the process must first lock
48	* the zones.lock, then lock the zone and then unlock the zones.lock.	48	* the zones.lock, then lock the zone and then unlock the zones.lock.
49	* This insures, that we can fiddle with the zones in runtime without	49	* This insures, that we can fiddle with the zones in runtime without
50	* affecting the processes.	50	* affecting the processes.
51	*	51	*
52	*/	52	*/
53		53
54	#include <arch/types.h>	54	#include <arch/types.h>
55	#include <mm/frame.h>	55	#include <mm/frame.h>
56	#include <mm/as.h>	56	#include <mm/as.h>
57	#include <panic.h>	57	#include <panic.h>
58	#include <debug.h>	58	#include <debug.h>
59	#include <adt/list.h>	59	#include <adt/list.h>
60	#include <synch/spinlock.h>	60	#include <synch/spinlock.h>
61	#include <synch/mutex.h>	61	#include <synch/mutex.h>
62	#include <synch/condvar.h>	62	#include <synch/condvar.h>
63	#include <arch/asm.h>	63	#include <arch/asm.h>
64	#include <arch.h>	64	#include <arch.h>
65	#include <print.h>	65	#include <print.h>
66	#include <align.h>	66	#include <align.h>
67	#include <mm/slab.h>	67	#include <mm/slab.h>
68	#include <bitops.h>	68	#include <bitops.h>
69	#include <macros.h>	69	#include <macros.h>
70	#include <config.h>	70	#include <config.h>
71		71
72	typedef struct {	72	typedef struct {
73	count_t refcount; /*< tracking of shared frames /	73	count_t refcount; /*< tracking of shared frames /
74	uint8_t buddy_order; /*< buddy system block order /	74	uint8_t buddy_order; /*< buddy system block order /
75	link_t buddy_link; /**< link to the next free block inside one	75	link_t buddy_link; /**< link to the next free block inside one
76	order */	76	order */
77	void parent; /< If allocated by slab, this points there /	77	void parent; /< If allocated by slab, this points there /
78	} frame_t;	78	} frame_t;
79		79
80	typedef struct {	80	typedef struct {
81	SPINLOCK_DECLARE(lock); /*< this lock protects everything below /	81	SPINLOCK_DECLARE(lock); /*< this lock protects everything below /
82	pfn_t base; /**< frame_no of the first frame in the frames	82	pfn_t base; /**< frame_no of the first frame in the frames
83	array */	83	array */
84	count_t count; /*< Size of zone /	84	count_t count; /*< Size of zone /
85		85
86	frame_t frames; /*< array of frame_t structures in this	86	frame_t frames; /*< array of frame_t structures in this
87	zone */	87	zone */
88	count_t free_count; /*< number of free frame_t structures /	88	count_t free_count; /*< number of free frame_t structures /
89	count_t busy_count; /*< number of busy frame_t structures /	89	count_t busy_count; /*< number of busy frame_t structures /
90		90
91	buddy_system_t buddy_system; /< buddy system for the zone /	91	buddy_system_t buddy_system; /< buddy system for the zone /
92	int flags;	92	int flags;
93	} zone_t;	93	} zone_t;
94		94
95	/*	95	/*
96	* The zoneinfo.lock must be locked when accessing zoneinfo structure.	96	* The zoneinfo.lock must be locked when accessing zoneinfo structure.
97	* Some of the attributes in zone_t structures are 'read-only'	97	* Some of the attributes in zone_t structures are 'read-only'
98	*/	98	*/
99		99
100	typedef struct {	100	typedef struct {
101	SPINLOCK_DECLARE(lock);	101	SPINLOCK_DECLARE(lock);
102	unsigned int count;	102	unsigned int count;
103	zone_t *info[ZONES_MAX];	103	zone_t *info[ZONES_MAX];
104	} zones_t;	104	} zones_t;
105		105
106	static zones_t zones;	106	static zones_t zones;
107		107
108	/*	108	/*
109	* Synchronization primitives used to sleep when there is no memory	109	* Synchronization primitives used to sleep when there is no memory
110	* available.	110	* available.
111	*/	111	*/
112	mutex_t mem_avail_mtx;	112	mutex_t mem_avail_mtx;
113	condvar_t mem_avail_cv;	113	condvar_t mem_avail_cv;
114	unsigned long mem_avail_frames = 0; /*< Number of available frames. /	114	unsigned long mem_avail_frames = 0; /*< Number of available frames. /
115	unsigned long mem_avail_gen = 0; /*< Generation counter. /	115	unsigned long mem_avail_gen = 0; /*< Generation counter. /
116		116
117	/********************/	117	/********************/
118	/* Helper functions */	118	/* Helper functions */
119	/********************/	119	/********************/
120		120
121	static inline index_t frame_index(zone_t zone, frame_t frame)	121	static inline index_t frame_index(zone_t zone, frame_t frame)
122	{	122	{
123	return (index_t) (frame - zone->frames);	123	return (index_t) (frame - zone->frames);
124	}	124	}
125		125
126	static inline index_t frame_index_abs(zone_t zone, frame_t frame)	126	static inline index_t frame_index_abs(zone_t zone, frame_t frame)
127	{	127	{
128	return (index_t) (frame - zone->frames) + zone->base;	128	return (index_t) (frame - zone->frames) + zone->base;
129	}	129	}
130		130
131	static inline int frame_index_valid(zone_t *zone, index_t index)	131	static inline int frame_index_valid(zone_t *zone, index_t index)
132	{	132	{
133	return (index < zone->count);	133	return (index < zone->count);
134	}	134	}
135		135
136	/** Compute pfn_t from frame_t pointer & zone pointer */	136	/** Compute pfn_t from frame_t pointer & zone pointer */
137	static index_t make_frame_index(zone_t zone, frame_t frame)	137	static index_t make_frame_index(zone_t zone, frame_t frame)
138	{	138	{
139	return (frame - zone->frames);	139	return (frame - zone->frames);
140	}	140	}
141		141
142	/** Initialize frame structure.	142	/** Initialize frame structure.
143	*	143	*
144	* @param frame Frame structure to be initialized.	144	* @param frame Frame structure to be initialized.
145	*/	145	*/
146	static void frame_initialize(frame_t *frame)	146	static void frame_initialize(frame_t *frame)
147	{	147	{
148	frame->refcount = 1;	148	frame->refcount = 1;
149	frame->buddy_order = 0;	149	frame->buddy_order = 0;
150	}	150	}
151		151
152	/**********************/	152	/**********************/
153	/* Zoneinfo functions */	153	/* Zoneinfo functions */
154	/**********************/	154	/**********************/
155		155
156	/** Insert-sort zone into zones list.	156	/** Insert-sort zone into zones list.
157	*	157	*
158	* @param newzone New zone to be inserted into zone list.	158	* @param newzone New zone to be inserted into zone list.
159	* @return Zone number on success, -1 on error.	159	* @return Zone number on success, -1 on error.
160	*/	160	*/
161	static int zones_add_zone(zone_t *newzone)	161	static int zones_add_zone(zone_t *newzone)
162	{	162	{
163	unsigned int i, j;	163	unsigned int i, j;
164	ipl_t ipl;	164	ipl_t ipl;
165	zone_t *z;	165	zone_t *z;
166		166
167	ipl = interrupts_disable();	167	ipl = interrupts_disable();
168	spinlock_lock(&zones.lock);	168	spinlock_lock(&zones.lock);
169		169
170	/* Try to merge */	170	/* Try to merge */
171	if (zones.count + 1 == ZONES_MAX) {	171	if (zones.count + 1 == ZONES_MAX) {
172	printf("Maximum zone count %u exceeded!\n", ZONES_MAX);	172	printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
173	spinlock_unlock(&zones.lock);	173	spinlock_unlock(&zones.lock);
174	interrupts_restore(ipl);	174	interrupts_restore(ipl);
175	return -1;	175	return -1;
176	}	176	}
177		177
178	for (i = 0; i < zones.count; i++) {	178	for (i = 0; i < zones.count; i++) {
179	/* Check for overflow */	179	/* Check for overflow */
180	z = zones.info[i];	180	z = zones.info[i];
181	if (overlaps(newzone->base, newzone->count, z->base,	181	if (overlaps(newzone->base, newzone->count, z->base,
182	z->count)) {	182	z->count)) {
183	printf("Zones overlap!\n");	183	printf("Zones overlap!\n");
184	return -1;	184	return -1;
185	}	185	}
186	if (newzone->base < z->base)	186	if (newzone->base < z->base)
187	break;	187	break;
188	}	188	}
189		189
190	/* Move other zones up */	190	/* Move other zones up */
191	for (j = i; j < zones.count; j++)	191	for (j = i; j < zones.count; j++)
192	zones.info[j + 1] = zones.info[j];	192	zones.info[j + 1] = zones.info[j];
193		193
194	zones.info[i] = newzone;	194	zones.info[i] = newzone;
195	zones.count++;	195	zones.count++;
196		196
197	spinlock_unlock(&zones.lock);	197	spinlock_unlock(&zones.lock);
198	interrupts_restore(ipl);	198	interrupts_restore(ipl);
199		199
200	return i;	200	return i;
201	}	201	}
202		202
203	/** Try to find a zone where can we find the frame.	203	/** Try to find a zone where can we find the frame.
204	*	204	*
205	* Assume interrupts are disabled.	205	* Assume interrupts are disabled.
206	*	206	*
207	* @param frame Frame number contained in zone.	207	* @param frame Frame number contained in zone.
208	* @param pzone If not null, it is used as zone hint. Zone index is	208	* @param pzone If not null, it is used as zone hint. Zone index is
209	* filled into the variable on success.	209	* filled into the variable on success.
210	* @return Pointer to locked zone containing frame.	210	* @return Pointer to locked zone containing frame.
211	*/	211	*/
212	static zone_t find_zone_and_lock(pfn_t frame, unsigned int pzone)	212	static zone_t find_zone_and_lock(pfn_t frame, unsigned int pzone)
213	{	213	{
214	unsigned int i;	214	unsigned int i;
215	unsigned int hint = pzone ? *pzone : 0;	215	unsigned int hint = pzone ? *pzone : 0;
216	zone_t *z;	216	zone_t *z;
217		217
218	spinlock_lock(&zones.lock);	218	spinlock_lock(&zones.lock);
219		219
220	if (hint >= zones.count)	220	if (hint >= zones.count)
221	hint = 0;	221	hint = 0;
222		222
223	i = hint;	223	i = hint;
224	do {	224	do {
225	z = zones.info[i];	225	z = zones.info[i];
226	spinlock_lock(&z->lock);	226	spinlock_lock(&z->lock);
227	if (z->base <= frame && z->base + z->count > frame) {	227	if (z->base <= frame && z->base + z->count > frame) {
228	/* Unlock the global lock */	228	/* Unlock the global lock */
229	spinlock_unlock(&zones.lock);	229	spinlock_unlock(&zones.lock);
230	if (pzone)	230	if (pzone)
231	*pzone = i;	231	*pzone = i;
232	return z;	232	return z;
233	}	233	}
234	spinlock_unlock(&z->lock);	234	spinlock_unlock(&z->lock);
235		235
236	i++;	236	i++;
237	if (i >= zones.count)	237	if (i >= zones.count)
238	i = 0;	238	i = 0;
239	} while (i != hint);	239	} while (i != hint);
240		240
241	spinlock_unlock(&zones.lock);	241	spinlock_unlock(&zones.lock);
242	return NULL;	242	return NULL;
243	}	243	}
244		244
245	/** @return True if zone can allocate specified order */	245	/** @return True if zone can allocate specified order */
246	static int zone_can_alloc(zone_t *z, uint8_t order)	246	static int zone_can_alloc(zone_t *z, uint8_t order)
247	{	247	{
248	return buddy_system_can_alloc(z->buddy_system, order);	248	return buddy_system_can_alloc(z->buddy_system, order);
249	}	249	}
250		250
251	/** Find and lock zone that can allocate order frames.	251	/** Find and lock zone that can allocate order frames.
252	*	252	*
253	* Assume interrupts are disabled.	253	* Assume interrupts are disabled.
254	*	254	*
255	* @param order Size (2^order) of free space we are trying to find.	255	* @param order Size (2^order) of free space we are trying to find.
256	* @param flags Required flags of the target zone.	256	* @param flags Required flags of the target zone.
257	* @param pzone Pointer to preferred zone or NULL, on return contains	257	* @param pzone Pointer to preferred zone or NULL, on return contains
258	* zone number.	258	* zone number.
259	*/	259	*/
260	static zone_t *	260	static zone_t *
261	find_free_zone_and_lock(uint8_t order, int flags, unsigned int *pzone)	261	find_free_zone_and_lock(uint8_t order, int flags, unsigned int *pzone)
262	{	262	{
263	unsigned int i;	263	unsigned int i;
264	zone_t *z;	264	zone_t *z;
265	unsigned int hint = pzone ? *pzone : 0;	265	unsigned int hint = pzone ? *pzone : 0;
266		266
267	/* Mask off flags that are not applicable. */	267	/* Mask off flags that are not applicable. */
268	flags &= FRAME_LOW_16_GiB;	268	flags &= FRAME_LOW_4_GiB;
269		269
270	spinlock_lock(&zones.lock);	270	spinlock_lock(&zones.lock);
271	if (hint >= zones.count)	271	if (hint >= zones.count)
272	hint = 0;	272	hint = 0;
273	i = hint;	273	i = hint;
274	do {	274	do {
275	z = zones.info[i];	275	z = zones.info[i];
276		276
277	spinlock_lock(&z->lock);	277	spinlock_lock(&z->lock);
278		278
279	/*	279	/*
280	* Check whether the zone meets the search criteria.	280	* Check whether the zone meets the search criteria.
281	*/	281	*/
282	if ((z->flags & flags) == flags) {	282	if ((z->flags & flags) == flags) {
283	/*	283	/*
284	* Check if the zone has 2^order frames area available.	284	* Check if the zone has 2^order frames area available.
285	*/	285	*/
286	if (zone_can_alloc(z, order)) {	286	if (zone_can_alloc(z, order)) {
287	spinlock_unlock(&zones.lock);	287	spinlock_unlock(&zones.lock);
288	if (pzone)	288	if (pzone)
289	*pzone = i;	289	*pzone = i;
290	return z;	290	return z;
291	}	291	}
292	}	292	}
293	spinlock_unlock(&z->lock);	293	spinlock_unlock(&z->lock);
294	if (++i >= zones.count)	294	if (++i >= zones.count)
295	i = 0;	295	i = 0;
296	} while (i != hint);	296	} while (i != hint);
297	spinlock_unlock(&zones.lock);	297	spinlock_unlock(&zones.lock);
298	return NULL;	298	return NULL;
299	}	299	}
300		300
301	/**************************/	301	/**************************/
302	/* Buddy system functions */	302	/* Buddy system functions */
303	/**************************/	303	/**************************/
304		304
305	/** Buddy system find_block implementation.	305	/** Buddy system find_block implementation.
306	*	306	*
307	* Find block that is parent of current list.	307	* Find block that is parent of current list.
308	* That means go to lower addresses, until such block is found	308	* That means go to lower addresses, until such block is found
309	*	309	*
310	* @param order Order of parent must be different then this	310	* @param order Order of parent must be different then this
311	* parameter!!	311	* parameter!!
312	*/	312	*/
313	static link_t zone_buddy_find_block(buddy_system_t b, link_t *child,	313	static link_t zone_buddy_find_block(buddy_system_t b, link_t *child,
314	uint8_t order)	314	uint8_t order)
315	{	315	{
316	frame_t *frame;	316	frame_t *frame;
317	zone_t *zone;	317	zone_t *zone;
318	index_t index;	318	index_t index;
319		319
320	frame = list_get_instance(child, frame_t, buddy_link);	320	frame = list_get_instance(child, frame_t, buddy_link);
321	zone = (zone_t *) b->data;	321	zone = (zone_t *) b->data;
322		322
323	index = frame_index(zone, frame);	323	index = frame_index(zone, frame);
324	do {	324	do {
325	if (zone->frames[index].buddy_order != order) {	325	if (zone->frames[index].buddy_order != order) {
326	return &zone->frames[index].buddy_link;	326	return &zone->frames[index].buddy_link;
327	}	327	}
328	} while(index-- > 0);	328	} while(index-- > 0);
329	return NULL;	329	return NULL;
330	}	330	}
331		331
332	/** Buddy system find_buddy implementation.	332	/** Buddy system find_buddy implementation.
333	*	333	*
334	* @param b Buddy system.	334	* @param b Buddy system.
335	* @param block Block for which buddy should be found.	335	* @param block Block for which buddy should be found.
336	*	336	*
337	* @return Buddy for given block if found.	337	* @return Buddy for given block if found.
338	*/	338	*/
339	static link_t zone_buddy_find_buddy(buddy_system_t b, link_t *block)	339	static link_t zone_buddy_find_buddy(buddy_system_t b, link_t *block)
340	{	340	{
341	frame_t *frame;	341	frame_t *frame;
342	zone_t *zone;	342	zone_t *zone;
343	index_t index;	343	index_t index;
344	bool is_left, is_right;	344	bool is_left, is_right;
345		345
346	frame = list_get_instance(block, frame_t, buddy_link);	346	frame = list_get_instance(block, frame_t, buddy_link);
347	zone = (zone_t *) b->data;	347	zone = (zone_t *) b->data;
348	ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),	348	ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
349	frame->buddy_order));	349	frame->buddy_order));
350		350
351	is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);	351	is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
352	is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);	352	is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
353		353
354	ASSERT(is_left ^ is_right);	354	ASSERT(is_left ^ is_right);
355	if (is_left) {	355	if (is_left) {
356	index = (frame_index(zone, frame)) +	356	index = (frame_index(zone, frame)) +
357	(1 << frame->buddy_order);	357	(1 << frame->buddy_order);
358	} else { /* if (is_right) */	358	} else { /* if (is_right) */
359	index = (frame_index(zone, frame)) -	359	index = (frame_index(zone, frame)) -
360	(1 << frame->buddy_order);	360	(1 << frame->buddy_order);
361	}	361	}
362		362
363	if (frame_index_valid(zone, index)) {	363	if (frame_index_valid(zone, index)) {
364	if (zone->frames[index].buddy_order == frame->buddy_order &&	364	if (zone->frames[index].buddy_order == frame->buddy_order &&
365	zone->frames[index].refcount == 0) {	365	zone->frames[index].refcount == 0) {
366	return &zone->frames[index].buddy_link;	366	return &zone->frames[index].buddy_link;
367	}	367	}
368	}	368	}
369		369
370	return NULL;	370	return NULL;
371	}	371	}
372		372
373	/** Buddy system bisect implementation.	373	/** Buddy system bisect implementation.
374	*	374	*
375	* @param b Buddy system.	375	* @param b Buddy system.
376	* @param block Block to bisect.	376	* @param block Block to bisect.
377	*	377	*
378	* @return Right block.	378	* @return Right block.
379	*/	379	*/
380	static link_t zone_buddy_bisect(buddy_system_t b, link_t *block)	380	static link_t zone_buddy_bisect(buddy_system_t b, link_t *block)
381	{	381	{
382	frame_t frame_l, frame_r;	382	frame_t frame_l, frame_r;
383		383
384	frame_l = list_get_instance(block, frame_t, buddy_link);	384	frame_l = list_get_instance(block, frame_t, buddy_link);
385	frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));	385	frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
386		386
387	return &frame_r->buddy_link;	387	return &frame_r->buddy_link;
388	}	388	}
389		389
390	/** Buddy system coalesce implementation.	390	/** Buddy system coalesce implementation.
391	*	391	*
392	* @param b Buddy system.	392	* @param b Buddy system.
393	* @param block_1 First block.	393	* @param block_1 First block.
394	* @param block_2 First block's buddy.	394	* @param block_2 First block's buddy.
395	*	395	*
396	* @return Coalesced block (actually block that represents lower	396	* @return Coalesced block (actually block that represents lower
397	* address).	397	* address).
398	*/	398	*/
399	static link_t zone_buddy_coalesce(buddy_system_t b, link_t *block_1,	399	static link_t zone_buddy_coalesce(buddy_system_t b, link_t *block_1,
400	link_t *block_2)	400	link_t *block_2)
401	{	401	{
402	frame_t frame1, frame2;	402	frame_t frame1, frame2;
403		403
404	frame1 = list_get_instance(block_1, frame_t, buddy_link);	404	frame1 = list_get_instance(block_1, frame_t, buddy_link);
405	frame2 = list_get_instance(block_2, frame_t, buddy_link);	405	frame2 = list_get_instance(block_2, frame_t, buddy_link);
406		406
407	return frame1 < frame2 ? block_1 : block_2;	407	return frame1 < frame2 ? block_1 : block_2;
408	}	408	}
409		409
410	/** Buddy system set_order implementation.	410	/** Buddy system set_order implementation.
411	*	411	*
412	* @param b Buddy system.	412	* @param b Buddy system.
413	* @param block Buddy system block.	413	* @param block Buddy system block.
414	* @param order Order to set.	414	* @param order Order to set.
415	*/	415	*/
416	static void zone_buddy_set_order(buddy_system_t b, link_t block,	416	static void zone_buddy_set_order(buddy_system_t b, link_t block,
417	uint8_t order)	417	uint8_t order)
418	{	418	{
419	frame_t *frame;	419	frame_t *frame;
420	frame = list_get_instance(block, frame_t, buddy_link);	420	frame = list_get_instance(block, frame_t, buddy_link);
421	frame->buddy_order = order;	421	frame->buddy_order = order;
422	}	422	}
423		423
424	/** Buddy system get_order implementation.	424	/** Buddy system get_order implementation.
425	*	425	*
426	* @param b Buddy system.	426	* @param b Buddy system.
427	* @param block Buddy system block.	427	* @param block Buddy system block.
428	*	428	*
429	* @return Order of block.	429	* @return Order of block.
430	*/	430	*/
431	static uint8_t zone_buddy_get_order(buddy_system_t b, link_t block)	431	static uint8_t zone_buddy_get_order(buddy_system_t b, link_t block)
432	{	432	{
433	frame_t *frame;	433	frame_t *frame;
434	frame = list_get_instance(block, frame_t, buddy_link);	434	frame = list_get_instance(block, frame_t, buddy_link);
435	return frame->buddy_order;	435	return frame->buddy_order;
436	}	436	}
437		437
438	/** Buddy system mark_busy implementation.	438	/** Buddy system mark_busy implementation.
439	*	439	*
440	* @param b Buddy system.	440	* @param b Buddy system.
441	* @param block Buddy system block.	441	* @param block Buddy system block.
442	*/	442	*/
443	static void zone_buddy_mark_busy(buddy_system_t b, link_t block)	443	static void zone_buddy_mark_busy(buddy_system_t b, link_t block)
444	{	444	{
445	frame_t * frame;	445	frame_t * frame;
446		446
447	frame = list_get_instance(block, frame_t, buddy_link);	447	frame = list_get_instance(block, frame_t, buddy_link);
448	frame->refcount = 1;	448	frame->refcount = 1;
449	}	449	}
450		450
451	/** Buddy system mark_available implementation.	451	/** Buddy system mark_available implementation.
452	*	452	*
453	* @param b Buddy system.	453	* @param b Buddy system.
454	* @param block Buddy system block.	454	* @param block Buddy system block.
455	*/	455	*/
456	static void zone_buddy_mark_available(buddy_system_t b, link_t block)	456	static void zone_buddy_mark_available(buddy_system_t b, link_t block)
457	{	457	{
458	frame_t *frame;	458	frame_t *frame;
459	frame = list_get_instance(block, frame_t, buddy_link);	459	frame = list_get_instance(block, frame_t, buddy_link);
460	frame->refcount = 0;	460	frame->refcount = 0;
461	}	461	}
462		462
463	static buddy_system_operations_t zone_buddy_system_operations = {	463	static buddy_system_operations_t zone_buddy_system_operations = {
464	.find_buddy = zone_buddy_find_buddy,	464	.find_buddy = zone_buddy_find_buddy,
465	.bisect = zone_buddy_bisect,	465	.bisect = zone_buddy_bisect,
466	.coalesce = zone_buddy_coalesce,	466	.coalesce = zone_buddy_coalesce,
467	.set_order = zone_buddy_set_order,	467	.set_order = zone_buddy_set_order,
468	.get_order = zone_buddy_get_order,	468	.get_order = zone_buddy_get_order,
469	.mark_busy = zone_buddy_mark_busy,	469	.mark_busy = zone_buddy_mark_busy,
470	.mark_available = zone_buddy_mark_available,	470	.mark_available = zone_buddy_mark_available,
471	.find_block = zone_buddy_find_block	471	.find_block = zone_buddy_find_block
472	};	472	};
473		473
474	/******************/	474	/******************/
475	/* Zone functions */	475	/* Zone functions */
476	/******************/	476	/******************/
477		477
478	/** Allocate frame in particular zone.	478	/** Allocate frame in particular zone.
479	*	479	*
480	* Assume zone is locked.	480	* Assume zone is locked.
481	* Panics if allocation is impossible.	481	* Panics if allocation is impossible.
482	*	482	*
483	* @param zone Zone to allocate from.	483	* @param zone Zone to allocate from.
484	* @param order Allocate exactly 2^order frames.	484	* @param order Allocate exactly 2^order frames.
485	*	485	*
486	* @return Frame index in zone.	486	* @return Frame index in zone.
487	*	487	*
488	*/	488	*/
489	static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)	489	static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)
490	{	490	{
491	pfn_t v;	491	pfn_t v;
492	link_t *tmp;	492	link_t *tmp;
493	frame_t *frame;	493	frame_t *frame;
494		494
495	/* Allocate frames from zone buddy system */	495	/* Allocate frames from zone buddy system */
496	tmp = buddy_system_alloc(zone->buddy_system, order);	496	tmp = buddy_system_alloc(zone->buddy_system, order);
497		497
498	ASSERT(tmp);	498	ASSERT(tmp);
499		499
500	/* Update zone information. */	500	/* Update zone information. */

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(root)/trunk/kernel/generic/src/mm/frame.c – Rev 3207 → 3208