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 pzone     Pointer to preferred zone or NULL, on return contains
 *          zone number.
 */
static zone_t *find_free_zone_and_lock(uint8_t order, unsigned int *pzone)
{
    unsigned int i;
    zone_t *z;
    unsigned int hint = pzone ? *pzone : 0;
   
    spinlock_lock(&zones.lock);
    if (hint >= zones.count)
        hint = 0;
    i = hint;
    do {
        z = zones.info[i];
       
        spinlock_lock(&z->lock);
 
        /* 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;
}
 
static void zone_buddy_print_id(buddy_system_t *b, link_t *block)
{
    frame_t *frame;
    zone_t *zone;
    index_t index;
 
    frame = list_get_instance(block, frame_t, buddy_link);
    zone = (zone_t *) b->data;
    index = frame_index(zone, frame);
    printf("%" PRIi, index);
}                    
 
/** 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,
    .print_id = zone_buddy_print_id
};
 
/******************/
/* 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;
    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, 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, pzone);
        if (!zone) {
            freed = slab_reclaim(SLAB_RECLAIM_ALL);
            if (freed)
                zone = find_free_zone_and_lock(order, 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;
 
    ipl = interrupts_disable();
    spinlock_lock(&zones.lock);
 
#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
   
    for (i = 0; i < zones.count; i++) {
        zone = zones.info[i];
        spinlock_lock(&zone->lock);
 
#ifdef __32_BITS__
        printf("%-2u   %10p %12" PRIc " %12" PRIc "\n",
            i, PFN2ADDR(zone->base), zone->free_count,
            zone->busy_count);
#endif
 
#ifdef __64_BITS__
        printf("%-2u   %18p %12" PRIc " %12" PRIc "\n", i,
            PFN2ADDR(zone->base), zone->free_count, zone->busy_count);
#endif
       
        spinlock_unlock(&zone->lock);
    }
   
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
}
 
/** 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;
 
    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) {
        printf("Zone not found.\n");
        goto out;
    }
   
    spinlock_lock(&zone->lock);
    printf("Memory zone information\n");
    printf("Zone base address: %p\n", PFN2ADDR(zone->base));
    printf("Zone size: %" PRIc " frames (%" PRIs " KB)\n", zone->count,
        SIZE2KB(FRAMES2SIZE(zone->count)));
    printf("Allocated space: %" PRIc " frames (%" PRIs " KB)\n",
        zone->busy_count, SIZE2KB(FRAMES2SIZE(zone->busy_count)));
    printf("Available space: %" PRIc " frames (%" PRIs " KB)\n",
        zone->free_count, SIZE2KB(FRAMES2SIZE(zone->free_count)));
    buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
    spinlock_unlock(&zone->lock);
   
out:
    spinlock_unlock(&zones.lock);
    interrupts_restore(ipl);
}
 
/** @}
 */
 
 

Rev 3187	Rev 3188
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 zones_mtx;	112	mutex_t mem_avail_mtx;
113	condvar_t zones_cv;	113	condvar_t mem_avail_cv;
-		114	unsigned long mem_avail_frames = 0; /*< Number of available frames. /
114	int new_freed_mem = false;	115	unsigned long mem_avail_gen = 0; /*< Generation counter. /
115		116
116	/********************/	117	/********************/
117	/* Helper functions */	118	/* Helper functions */
118	/********************/	119	/********************/
119		120
120	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)
121	{	122	{
122	return (index_t) (frame - zone->frames);	123	return (index_t) (frame - zone->frames);
123	}	124	}
124		125
125	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)
126	{	127	{
127	return (index_t) (frame - zone->frames) + zone->base;	128	return (index_t) (frame - zone->frames) + zone->base;
128	}	129	}
129		130
130	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)
131	{	132	{
132	return (index < zone->count);	133	return (index < zone->count);
133	}	134	}
134		135
135	/** Compute pfn_t from frame_t pointer & zone pointer */	136	/** Compute pfn_t from frame_t pointer & zone pointer */
136	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)
137	{	138	{
138	return (frame - zone->frames);	139	return (frame - zone->frames);
139	}	140	}
140		141
141	/** Initialize frame structure.	142	/** Initialize frame structure.
142	*	143	*
143	* @param framei Frame structure to be initialized.	144	* @param frame Frame structure to be initialized.
144	*/	145	*/
145	static void frame_initialize(frame_t *frame)	146	static void frame_initialize(frame_t *frame)
146	{	147	{
147	frame->refcount = 1;	148	frame->refcount = 1;
148	frame->buddy_order = 0;	149	frame->buddy_order = 0;
149	}	150	}
150		151
151	/**********************/	152	/**********************/
152	/* Zoneinfo functions */	153	/* Zoneinfo functions */
153	/**********************/	154	/**********************/
154		155
155	/** Insert-sort zone into zones list.	156	/** Insert-sort zone into zones list.
156	*	157	*
157	* @param newzone New zone to be inserted into zone list.	158	* @param newzone New zone to be inserted into zone list.
158	* @return Zone number on success, -1 on error.	159	* @return Zone number on success, -1 on error.
159	*/	160	*/
160	static int zones_add_zone(zone_t *newzone)	161	static int zones_add_zone(zone_t *newzone)
161	{	162	{
162	unsigned int i, j;	163	unsigned int i, j;
163	ipl_t ipl;	164	ipl_t ipl;
164	zone_t *z;	165	zone_t *z;
165		166
166	ipl = interrupts_disable();	167	ipl = interrupts_disable();
167	spinlock_lock(&zones.lock);	168	spinlock_lock(&zones.lock);
168		169
169	/* Try to merge */	170	/* Try to merge */
170	if (zones.count + 1 == ZONES_MAX) {	171	if (zones.count + 1 == ZONES_MAX) {
171	printf("Maximum zone count %u exceeded!\n", ZONES_MAX);	172	printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
172	spinlock_unlock(&zones.lock);	173	spinlock_unlock(&zones.lock);
173	interrupts_restore(ipl);	174	interrupts_restore(ipl);
174	return -1;	175	return -1;
175	}	176	}
176		177
177	for (i = 0; i < zones.count; i++) {	178	for (i = 0; i < zones.count; i++) {
178	/* Check for overflow */	179	/* Check for overflow */
179	z = zones.info[i];	180	z = zones.info[i];
180	if (overlaps(newzone->base, newzone->count, z->base,	181	if (overlaps(newzone->base, newzone->count, z->base,
181	z->count)) {	182	z->count)) {
182	printf("Zones overlap!\n");	183	printf("Zones overlap!\n");
183	return -1;	184	return -1;
184	}	185	}
185	if (newzone->base < z->base)	186	if (newzone->base < z->base)
186	break;	187	break;
187	}	188	}
188		189
189	/* Move other zones up */	190	/* Move other zones up */
190	for (j = i; j < zones.count; j++)	191	for (j = i; j < zones.count; j++)
191	zones.info[j + 1] = zones.info[j];	192	zones.info[j + 1] = zones.info[j];
192		193
193	zones.info[i] = newzone;	194	zones.info[i] = newzone;
194	zones.count++;	195	zones.count++;
195		196
196	spinlock_unlock(&zones.lock);	197	spinlock_unlock(&zones.lock);
197	interrupts_restore(ipl);	198	interrupts_restore(ipl);
198		199
199	return i;	200	return i;
200	}	201	}
201		202
202	/**	203	/**
203	* Try to find a zone where can we find the frame.	204	* Try to find a zone where can we find the frame.
204	*	205	*
205	* Assume interrupts are disabled.	206	* Assume interrupts are disabled.
206	*	207	*
207	* @param frame Frame number contained in zone.	208	* @param frame Frame number contained in zone.
208	* @param pzone If not null, it is used as zone hint. Zone index is	209	* @param pzone If not null, it is used as zone hint. Zone index is
209	* filled into the variable on success.	210	* filled into the variable on success.
210	* @return Pointer to locked zone containing frame.	211	* @return Pointer to locked zone containing frame.
211	*/	212	*/
212	static zone_t find_zone_and_lock(pfn_t frame, unsigned int pzone)	213	static zone_t find_zone_and_lock(pfn_t frame, unsigned int pzone)
213	{	214	{
214	unsigned int i;	215	unsigned int i;
215	unsigned int hint = pzone ? *pzone : 0;	216	unsigned int hint = pzone ? *pzone : 0;
216	zone_t *z;	217	zone_t *z;
217		218
218	spinlock_lock(&zones.lock);	219	spinlock_lock(&zones.lock);
219		220
220	if (hint >= zones.count)	221	if (hint >= zones.count)
221	hint = 0;	222	hint = 0;
222		223
223	i = hint;	224	i = hint;
224	do {	225	do {
225	z = zones.info[i];	226	z = zones.info[i];
226	spinlock_lock(&z->lock);	227	spinlock_lock(&z->lock);
227	if (z->base <= frame && z->base + z->count > frame) {	228	if (z->base <= frame && z->base + z->count > frame) {
228	/* Unlock the global lock */	229	/* Unlock the global lock */
229	spinlock_unlock(&zones.lock);	230	spinlock_unlock(&zones.lock);
230	if (pzone)	231	if (pzone)
231	*pzone = i;	232	*pzone = i;
232	return z;	233	return z;
233	}	234	}
234	spinlock_unlock(&z->lock);	235	spinlock_unlock(&z->lock);
235		236
236	i++;	237	i++;
237	if (i >= zones.count)	238	if (i >= zones.count)
238	i = 0;	239	i = 0;
239	} while(i != hint);	240	} while(i != hint);
240		241
241	spinlock_unlock(&zones.lock);	242	spinlock_unlock(&zones.lock);
242	return NULL;	243	return NULL;
243	}	244	}
244		245
245	/** @return True if zone can allocate specified order */	246	/** @return True if zone can allocate specified order */
246	static int zone_can_alloc(zone_t *z, uint8_t order)	247	static int zone_can_alloc(zone_t *z, uint8_t order)
247	{	248	{
248	return buddy_system_can_alloc(z->buddy_system, order);	249	return buddy_system_can_alloc(z->buddy_system, order);
249	}	250	}
250		251
251	/** Find and lock zone that can allocate order frames.	252	/** Find and lock zone that can allocate order frames.
252	*	253	*
253	* Assume interrupts are disabled.	254	* Assume interrupts are disabled.
254	*	255	*
255	* @param order Size (2^order) of free space we are trying to find.	256	* @param order Size (2^order) of free space we are trying to find.
256	* @param pzone Pointer to preferred zone or NULL, on return contains	257	* @param pzone Pointer to preferred zone or NULL, on return contains
257	* zone number.	258	* zone number.
258	*/	259	*/
259	static zone_t find_free_zone_and_lock(uint8_t order, unsigned int pzone)	260	static zone_t find_free_zone_and_lock(uint8_t order, unsigned int pzone)
260	{	261	{
261	unsigned int i;	262	unsigned int i;
262	zone_t *z;	263	zone_t *z;
263	unsigned int hint = pzone ? *pzone : 0;	264	unsigned int hint = pzone ? *pzone : 0;
264		265
265	spinlock_lock(&zones.lock);	266	spinlock_lock(&zones.lock);
266	if (hint >= zones.count)	267	if (hint >= zones.count)
267	hint = 0;	268	hint = 0;
268	i = hint;	269	i = hint;
269	do {	270	do {
270	z = zones.info[i];	271	z = zones.info[i];
271		272
272	spinlock_lock(&z->lock);	273	spinlock_lock(&z->lock);
273		274
274	/* Check if the zone has 2^order frames area available */	275	/* Check if the zone has 2^order frames area available */
275	if (zone_can_alloc(z, order)) {	276	if (zone_can_alloc(z, order)) {
276	spinlock_unlock(&zones.lock);	277	spinlock_unlock(&zones.lock);
277	if (pzone)	278	if (pzone)
278	*pzone = i;	279	*pzone = i;
279	return z;	280	return z;
280	}	281	}
281	spinlock_unlock(&z->lock);	282	spinlock_unlock(&z->lock);
282	if (++i >= zones.count)	283	if (++i >= zones.count)
283	i = 0;	284	i = 0;
284	} while(i != hint);	285	} while(i != hint);
285	spinlock_unlock(&zones.lock);	286	spinlock_unlock(&zones.lock);
286	return NULL;	287	return NULL;
287	}	288	}
288		289
289	/**************************/	290	/**************************/
290	/* Buddy system functions */	291	/* Buddy system functions */
291	/**************************/	292	/**************************/
292		293
293	/** Buddy system find_block implementation.	294	/** Buddy system find_block implementation.
294	*	295	*
295	* Find block that is parent of current list.	296	* Find block that is parent of current list.
296	* That means go to lower addresses, until such block is found	297	* That means go to lower addresses, until such block is found
297	*	298	*
298	* @param order Order of parent must be different then this	299	* @param order Order of parent must be different then this
299	* parameter!!	300	* parameter!!
300	*/	301	*/
301	static link_t zone_buddy_find_block(buddy_system_t b, link_t *child,	302	static link_t zone_buddy_find_block(buddy_system_t b, link_t *child,
302	uint8_t order)	303	uint8_t order)
303	{	304	{
304	frame_t *frame;	305	frame_t *frame;
305	zone_t *zone;	306	zone_t *zone;
306	index_t index;	307	index_t index;
307		308
308	frame = list_get_instance(child, frame_t, buddy_link);	309	frame = list_get_instance(child, frame_t, buddy_link);
309	zone = (zone_t *) b->data;	310	zone = (zone_t *) b->data;
310		311
311	index = frame_index(zone, frame);	312	index = frame_index(zone, frame);
312	do {	313	do {
313	if (zone->frames[index].buddy_order != order) {	314	if (zone->frames[index].buddy_order != order) {
314	return &zone->frames[index].buddy_link;	315	return &zone->frames[index].buddy_link;
315	}	316	}
316	} while(index-- > 0);	317	} while(index-- > 0);
317	return NULL;	318	return NULL;
318	}	319	}
319		320
320	static void zone_buddy_print_id(buddy_system_t b, link_t block)	321	static void zone_buddy_print_id(buddy_system_t b, link_t block)
321	{	322	{
322	frame_t *frame;	323	frame_t *frame;
323	zone_t *zone;	324	zone_t *zone;
324	index_t index;	325	index_t index;
325		326
326	frame = list_get_instance(block, frame_t, buddy_link);	327	frame = list_get_instance(block, frame_t, buddy_link);
327	zone = (zone_t *) b->data;	328	zone = (zone_t *) b->data;
328	index = frame_index(zone, frame);	329	index = frame_index(zone, frame);
329	printf("%" PRIi, index);	330	printf("%" PRIi, index);
330	}	331	}
331		332
332	/** Buddy system find_buddy implementation.	333	/** Buddy system find_buddy implementation.
333	*	334	*
334	* @param b Buddy system.	335	* @param b Buddy system.
335	* @param block Block for which buddy should be found.	336	* @param block Block for which buddy should be found.
336	*	337	*
337	* @return Buddy for given block if found.	338	* @return Buddy for given block if found.
338	*/	339	*/
339	static link_t zone_buddy_find_buddy(buddy_system_t b, link_t *block)	340	static link_t zone_buddy_find_buddy(buddy_system_t b, link_t *block)
340	{	341	{
341	frame_t *frame;	342	frame_t *frame;
342	zone_t *zone;	343	zone_t *zone;
343	index_t index;	344	index_t index;
344	bool is_left, is_right;	345	bool is_left, is_right;
345		346
346	frame = list_get_instance(block, frame_t, buddy_link);	347	frame = list_get_instance(block, frame_t, buddy_link);
347	zone = (zone_t *) b->data;	348	zone = (zone_t *) b->data;
348	ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),	349	ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
349	frame->buddy_order));	350	frame->buddy_order));
350		351
351	is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);	352	is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
352	is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);	353	is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
353		354
354	ASSERT(is_left ^ is_right);	355	ASSERT(is_left ^ is_right);
355	if (is_left) {	356	if (is_left) {
356	index = (frame_index(zone, frame)) +	357	index = (frame_index(zone, frame)) +
357	(1 << frame->buddy_order);	358	(1 << frame->buddy_order);
358	} else { /* if (is_right) */	359	} else { /* if (is_right) */
359	index = (frame_index(zone, frame)) -	360	index = (frame_index(zone, frame)) -
360	(1 << frame->buddy_order);	361	(1 << frame->buddy_order);
361	}	362	}
362		363
363	if (frame_index_valid(zone, index)) {	364	if (frame_index_valid(zone, index)) {
364	if (zone->frames[index].buddy_order == frame->buddy_order &&	365	if (zone->frames[index].buddy_order == frame->buddy_order &&
365	zone->frames[index].refcount == 0) {	366	zone->frames[index].refcount == 0) {
366	return &zone->frames[index].buddy_link;	367	return &zone->frames[index].buddy_link;
367	}	368	}
368	}	369	}
369		370
370	return NULL;	371	return NULL;
371	}	372	}
372		373
373	/** Buddy system bisect implementation.	374	/** Buddy system bisect implementation.
374	*	375	*
375	* @param b Buddy system.	376	* @param b Buddy system.
376	* @param block Block to bisect.	377	* @param block Block to bisect.
377	*	378	*
378	* @return Right block.	379	* @return Right block.
379	*/	380	*/
380	static link_t zone_buddy_bisect(buddy_system_t b, link_t *block)	381	static link_t zone_buddy_bisect(buddy_system_t b, link_t *block)
381	{	382	{
382	frame_t frame_l, frame_r;	383	frame_t frame_l, frame_r;
383		384
384	frame_l = list_get_instance(block, frame_t, buddy_link);	385	frame_l = list_get_instance(block, frame_t, buddy_link);
385	frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));	386	frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
386		387
387	return &frame_r->buddy_link;	388	return &frame_r->buddy_link;
388	}	389	}
389		390
390	/** Buddy system coalesce implementation.	391	/** Buddy system coalesce implementation.
391	*	392	*
392	* @param b Buddy system.	393	* @param b Buddy system.
393	* @param block_1 First block.	394	* @param block_1 First block.
394	* @param block_2 First block's buddy.	395	* @param block_2 First block's buddy.
395	*	396	*
396	* @return Coalesced block (actually block that represents lower	397	* @return Coalesced block (actually block that represents lower
397	* address).	398	* address).
398	*/	399	*/
399	static link_t zone_buddy_coalesce(buddy_system_t b, link_t *block_1,	400	static link_t zone_buddy_coalesce(buddy_system_t b, link_t *block_1,
400	link_t *block_2)	401	link_t *block_2)
401	{	402	{
402	frame_t frame1, frame2;	403	frame_t frame1, frame2;
403		404
404	frame1 = list_get_instance(block_1, frame_t, buddy_link);	405	frame1 = list_get_instance(block_1, frame_t, buddy_link);
405	frame2 = list_get_instance(block_2, frame_t, buddy_link);	406	frame2 = list_get_instance(block_2, frame_t, buddy_link);
406		407
407	return frame1 < frame2 ? block_1 : block_2;	408	return frame1 < frame2 ? block_1 : block_2;
408	}	409	}
409		410
410	/** Buddy system set_order implementation.	411	/** Buddy system set_order implementation.
411	*	412	*
412	* @param b Buddy system.	413	* @param b Buddy system.
413	* @param block Buddy system block.	414	* @param block Buddy system block.
414	* @param order Order to set.	415	* @param order Order to set.
415	*/	416	*/
416	static void zone_buddy_set_order(buddy_system_t b, link_t block,	417	static void zone_buddy_set_order(buddy_system_t b, link_t block,
417	uint8_t order)	418	uint8_t order)
418	{	419	{
419	frame_t *frame;	420	frame_t *frame;
420	frame = list_get_instance(block, frame_t, buddy_link);	421	frame = list_get_instance(block, frame_t, buddy_link);
421	frame->buddy_order = order;	422	frame->buddy_order = order;
422	}	423	}
423		424
424	/** Buddy system get_order implementation.	425	/** Buddy system get_order implementation.
425	*	426	*
426	* @param b Buddy system.	427	* @param b Buddy system.
427	* @param block Buddy system block.	428	* @param block Buddy system block.
428	*	429	*
429	* @return Order of block.	430	* @return Order of block.
430	*/	431	*/
431	static uint8_t zone_buddy_get_order(buddy_system_t b, link_t block)	432	static uint8_t zone_buddy_get_order(buddy_system_t b, link_t block)
432	{	433	{
433	frame_t *frame;	434	frame_t *frame;
434	frame = list_get_instance(block, frame_t, buddy_link);	435	frame = list_get_instance(block, frame_t, buddy_link);
435	return frame->buddy_order;	436	return frame->buddy_order;
436	}	437	}
437		438
438	/** Buddy system mark_busy implementation.	439	/** Buddy system mark_busy implementation.
439	*	440	*
440	* @param b Buddy system.	441	* @param b Buddy system.
441	* @param block Buddy system block.	442	* @param block Buddy system block.
442	*/	443	*/
443	static void zone_buddy_mark_busy(buddy_system_t b, link_t block)	444	static void zone_buddy_mark_busy(buddy_system_t b, link_t block)
444	{	445	{
445	frame_t * frame;	446	frame_t * frame;
446		447
447	frame = list_get_instance(block, frame_t, buddy_link);	448	frame = list_get_instance(block, frame_t, buddy_link);
448	frame->refcount = 1;	449	frame->refcount = 1;
449	}	450	}
450		451
451	/** Buddy system mark_available implementation.	452	/** Buddy system mark_available implementation.
452	*	453	*
453	* @param b Buddy system.	454	* @param b Buddy system.
454	* @param block Buddy system block.	455	* @param block Buddy system block.
455	*/	456	*/
456	static void zone_buddy_mark_available(buddy_system_t b, link_t block)	457	static void zone_buddy_mark_available(buddy_system_t b, link_t block)
457	{	458	{
458	frame_t *frame;	459	frame_t *frame;
459	frame = list_get_instance(block, frame_t, buddy_link);	460	frame = list_get_instance(block, frame_t, buddy_link);
460	frame->refcount = 0;	461	frame->refcount = 0;
461	}	462	}
462		463
463	static buddy_system_operations_t zone_buddy_system_operations = {	464	static buddy_system_operations_t zone_buddy_system_operations = {
464	.find_buddy = zone_buddy_find_buddy,	465	.find_buddy = zone_buddy_find_buddy,
465	.bisect = zone_buddy_bisect,	466	.bisect = zone_buddy_bisect,
466	.coalesce = zone_buddy_coalesce,	467	.coalesce = zone_buddy_coalesce,
467	.set_order = zone_buddy_set_order,	468	.set_order = zone_buddy_set_order,
468	.get_order = zone_buddy_get_order,	469	.get_order = zone_buddy_get_order,
469	.mark_busy = zone_buddy_mark_busy,	470	.mark_busy = zone_buddy_mark_busy,
470	.mark_available = zone_buddy_mark_available,	471	.mark_available = zone_buddy_mark_available,
471	.find_block = zone_buddy_find_block,	472	.find_block = zone_buddy_find_block,
472	.print_id = zone_buddy_print_id	473	.print_id = zone_buddy_print_id
473	};	474	};
474		475
475	/******************/	476	/******************/
476	/* Zone functions */	477	/* Zone functions */
477	/******************/	478	/******************/
478		479
479	/** Allocate frame in particular zone.	480	/** Allocate frame in particular zone.
480	*	481	*
481	* Assume zone is locked.	482	* Assume zone is locked.
482	* Panics if allocation is impossible.	483	* Panics if allocation is impossible.
483	*	484	*
484	* @param zone Zone to allocate from.	485	* @param zone Zone to allocate from.
485	* @param order Allocate exactly 2^order frames.	486	* @param order Allocate exactly 2^order frames.
486	*	487	*
487	* @return Frame index in zone.	488	* @return Frame index in zone.
488	*	489	*
489	*/	490	*/
490	static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)	491	static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)
491	{	492	{
492	pfn_t v;	493	pfn_t v;
493	link_t *tmp;	494	link_t *tmp;
494	frame_t *frame;	495	frame_t *frame;
495		496
496	/* Allocate frames from zone buddy system */	497	/* Allocate frames from zone buddy system */
497	tmp = buddy_system_alloc(zone->buddy_system, order);	498	tmp = buddy_system_alloc(zone->buddy_system, order);
498		499
499	ASSERT(tmp);	500	ASSERT(tmp);

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(root)/trunk/kernel/generic/src/mm/frame.c @ 4204 – Rev 3187 → 3188