Subversion Repositories HelenOS

Rev

Rev 3149 | Rev 4344 | Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  1. /*
  2.  * Copyright (c) 2001-2005 Jakub Jermar
  3.  * Copyright (c) 2005 Sergey Bondari
  4.  * All rights reserved.
  5.  *
  6.  * Redistribution and use in source and binary forms, with or without
  7.  * modification, are permitted provided that the following conditions
  8.  * are met:
  9.  *
  10.  * - Redistributions of source code must retain the above copyright
  11.  *   notice, this list of conditions and the following disclaimer.
  12.  * - Redistributions in binary form must reproduce the above copyright
  13.  *   notice, this list of conditions and the following disclaimer in the
  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
  16.  *   derived from this software without specific prior written permission.
  17.  *
  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
  20.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  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
  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
  27.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28.  */
  29.  
  30. /** @addtogroup genericmm
  31.  * @{
  32.  */
  33.  
  34. /**
  35.  * @file
  36.  * @brief   Physical frame allocator.
  37.  *
  38.  * This file contains the physical frame allocator and memory zone management.
  39.  * The frame allocator is built on top of the buddy allocator.
  40.  *
  41.  * @see buddy.c
  42.  */
  43.  
  44. /*
  45.  * Locking order
  46.  *
  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.
  49.  * This insures, that we can fiddle with the zones in runtime without
  50.  * affecting the processes.
  51.  *
  52.  */
  53.  
  54. #include <arch/types.h>
  55. #include <mm/frame.h>
  56. #include <mm/as.h>
  57. #include <panic.h>
  58. #include <debug.h>
  59. #include <adt/list.h>
  60. #include <synch/spinlock.h>
  61. #include <synch/mutex.h>
  62. #include <synch/condvar.h>
  63. #include <arch/asm.h>
  64. #include <arch.h>
  65. #include <print.h>
  66. #include <align.h>
  67. #include <mm/slab.h>
  68. #include <bitops.h>
  69. #include <macros.h>
  70. #include <config.h>
  71.  
  72. typedef struct {
  73.     count_t refcount;   /**< tracking of shared frames  */
  74.     uint8_t buddy_order;    /**< buddy system block order */
  75.     link_t buddy_link;  /**< link to the next free block inside one
  76.                      order */
  77.     void *parent;           /**< If allocated by slab, this points there */
  78. } frame_t;
  79.  
  80. typedef struct {
  81.     SPINLOCK_DECLARE(lock); /**< this lock protects everything below */
  82.     pfn_t base;     /**< frame_no of the first frame in the frames
  83.                      array */
  84.     count_t count;          /**< Size of zone */
  85.  
  86.     frame_t *frames;    /**< array of frame_t structures in this
  87.                      zone */
  88.     count_t free_count; /**< number of free frame_t structures */
  89.     count_t busy_count; /**< number of busy frame_t structures */
  90.    
  91.     buddy_system_t *buddy_system; /**< buddy system for the zone */
  92.     int flags;
  93. } zone_t;
  94.  
  95. /*
  96.  * The zoneinfo.lock must be locked when accessing zoneinfo structure.
  97.  * Some of the attributes in zone_t structures are 'read-only'
  98.  */
  99.  
  100. typedef struct {
  101.     SPINLOCK_DECLARE(lock);
  102.     unsigned int count;
  103.     zone_t *info[ZONES_MAX];
  104. } zones_t;
  105.  
  106. static zones_t zones;
  107.  
  108. /*
  109.  * Synchronization primitives used to sleep when there is no memory
  110.  * available.
  111.  */
  112. mutex_t mem_avail_mtx;
  113. condvar_t mem_avail_cv;
  114. unsigned long mem_avail_frames = 0; /**< Number of available frames. */
  115. unsigned long mem_avail_gen = 0;    /**< Generation counter. */
  116.  
  117. /********************/
  118. /* Helper functions */
  119. /********************/
  120.  
  121. static inline index_t frame_index(zone_t *zone, frame_t *frame)
  122. {
  123.     return (index_t) (frame - zone->frames);
  124. }
  125.  
  126. static inline index_t frame_index_abs(zone_t *zone, frame_t *frame)
  127. {
  128.     return (index_t) (frame - zone->frames) + zone->base;
  129. }
  130.  
  131. static inline int frame_index_valid(zone_t *zone, index_t index)
  132. {
  133.     return (index < zone->count);
  134. }
  135.  
  136. /** Compute pfn_t from frame_t pointer & zone pointer */
  137. static index_t make_frame_index(zone_t *zone, frame_t *frame)
  138. {
  139.     return (frame - zone->frames);
  140. }
  141.  
  142. /** Initialize frame structure.
  143.  *
  144.  * @param frame     Frame structure to be initialized.
  145.  */
  146. static void frame_initialize(frame_t *frame)
  147. {
  148.     frame->refcount = 1;
  149.     frame->buddy_order = 0;
  150. }
  151.  
  152. /**********************/
  153. /* Zoneinfo functions */
  154. /**********************/
  155.  
  156. /** Insert-sort zone into zones list.
  157.  *
  158.  * @param newzone   New zone to be inserted into zone list.
  159.  * @return      Zone number on success, -1 on error.
  160.  */
  161. static int zones_add_zone(zone_t *newzone)
  162. {
  163.     unsigned int i, j;
  164.     ipl_t ipl;
  165.     zone_t *z;
  166.  
  167.     ipl = interrupts_disable();
  168.     spinlock_lock(&zones.lock);
  169.    
  170.     /* Try to merge */
  171.     if (zones.count + 1 == ZONES_MAX) {
  172.         printf("Maximum zone count %u exceeded!\n", ZONES_MAX);
  173.         spinlock_unlock(&zones.lock);
  174.         interrupts_restore(ipl);
  175.         return -1;
  176.     }
  177.    
  178.     for (i = 0; i < zones.count; i++) {
  179.         /* Check for overflow */
  180.         z = zones.info[i];
  181.         if (overlaps(newzone->base, newzone->count, z->base,
  182.             z->count)) {
  183.             printf("Zones overlap!\n");
  184.             return -1;
  185.         }
  186.         if (newzone->base < z->base)
  187.             break;
  188.     }
  189.    
  190.     /* Move other zones up */
  191.     for (j = i; j < zones.count; j++)
  192.         zones.info[j + 1] = zones.info[j];
  193.    
  194.     zones.info[i] = newzone;
  195.     zones.count++;
  196.    
  197.     spinlock_unlock(&zones.lock);
  198.     interrupts_restore(ipl);
  199.  
  200.     return i;
  201. }
  202.  
  203. /**
  204.  * Try to find a zone where can we find the frame.
  205.  *
  206.  * Assume interrupts are disabled.
  207.  *
  208.  * @param frame     Frame number contained in zone.
  209.  * @param pzone     If not null, it is used as zone hint. Zone index is
  210.  *          filled into the variable on success.
  211.  * @return      Pointer to locked zone containing frame.
  212.  */
  213. static zone_t *find_zone_and_lock(pfn_t frame, unsigned int *pzone)
  214. {
  215.     unsigned int i;
  216.     unsigned int hint = pzone ? *pzone : 0;
  217.     zone_t *z;
  218.    
  219.     spinlock_lock(&zones.lock);
  220.  
  221.     if (hint >= zones.count)
  222.         hint = 0;
  223.    
  224.     i = hint;
  225.     do {
  226.         z = zones.info[i];
  227.         spinlock_lock(&z->lock);
  228.         if (z->base <= frame && z->base + z->count > frame) {
  229.             /* Unlock the global lock */
  230.             spinlock_unlock(&zones.lock);
  231.             if (pzone)
  232.                 *pzone = i;
  233.             return z;
  234.         }
  235.         spinlock_unlock(&z->lock);
  236.  
  237.         i++;
  238.         if (i >= zones.count)
  239.             i = 0;
  240.     } while(i != hint);
  241.  
  242.     spinlock_unlock(&zones.lock);
  243.     return NULL;
  244. }
  245.  
  246. /** @return True if zone can allocate specified order */
  247. static int zone_can_alloc(zone_t *z, uint8_t order)
  248. {
  249.     return buddy_system_can_alloc(z->buddy_system, order);
  250. }
  251.  
  252. /** Find and lock zone that can allocate order frames.
  253.  *
  254.  * Assume interrupts are disabled.
  255.  *
  256.  * @param order     Size (2^order) of free space we are trying to find.
  257.  * @param pzone     Pointer to preferred zone or NULL, on return contains
  258.  *          zone number.
  259.  */
  260. static zone_t *find_free_zone_and_lock(uint8_t order, unsigned int *pzone)
  261. {
  262.     unsigned int i;
  263.     zone_t *z;
  264.     unsigned int hint = pzone ? *pzone : 0;
  265.    
  266.     spinlock_lock(&zones.lock);
  267.     if (hint >= zones.count)
  268.         hint = 0;
  269.     i = hint;
  270.     do {
  271.         z = zones.info[i];
  272.        
  273.         spinlock_lock(&z->lock);
  274.  
  275.         /* Check if the zone has 2^order frames area available  */
  276.         if (zone_can_alloc(z, order)) {
  277.             spinlock_unlock(&zones.lock);
  278.             if (pzone)
  279.                 *pzone = i;
  280.             return z;
  281.         }
  282.         spinlock_unlock(&z->lock);
  283.         if (++i >= zones.count)
  284.             i = 0;
  285.     } while(i != hint);
  286.     spinlock_unlock(&zones.lock);
  287.     return NULL;
  288. }
  289.  
  290. /**************************/
  291. /* Buddy system functions */
  292. /**************************/
  293.  
  294. /** Buddy system find_block implementation.
  295.  *
  296.  * Find block that is parent of current list.
  297.  * That means go to lower addresses, until such block is found
  298.  *
  299.  * @param order     Order of parent must be different then this
  300.  *          parameter!!
  301.  */
  302. static link_t *zone_buddy_find_block(buddy_system_t *b, link_t *child,
  303.     uint8_t order)
  304. {
  305.     frame_t *frame;
  306.     zone_t *zone;
  307.     index_t index;
  308.    
  309.     frame = list_get_instance(child, frame_t, buddy_link);
  310.     zone = (zone_t *) b->data;
  311.  
  312.     index = frame_index(zone, frame);
  313.     do {
  314.         if (zone->frames[index].buddy_order != order) {
  315.             return &zone->frames[index].buddy_link;
  316.         }
  317.     } while(index-- > 0);
  318.     return NULL;
  319. }
  320.  
  321. static void zone_buddy_print_id(buddy_system_t *b, link_t *block)
  322. {
  323.     frame_t *frame;
  324.     zone_t *zone;
  325.     index_t index;
  326.  
  327.     frame = list_get_instance(block, frame_t, buddy_link);
  328.     zone = (zone_t *) b->data;
  329.     index = frame_index(zone, frame);
  330.     printf("%" PRIi, index);
  331. }                    
  332.  
  333. /** Buddy system find_buddy implementation.
  334.  *
  335.  * @param b     Buddy system.
  336.  * @param block     Block for which buddy should be found.
  337.  *
  338.  * @return      Buddy for given block if found.
  339.  */
  340. static link_t *zone_buddy_find_buddy(buddy_system_t *b, link_t *block)
  341. {
  342.     frame_t *frame;
  343.     zone_t *zone;
  344.     index_t index;
  345.     bool is_left, is_right;
  346.  
  347.     frame = list_get_instance(block, frame_t, buddy_link);
  348.     zone = (zone_t *) b->data;
  349.     ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame),
  350.         frame->buddy_order));
  351.    
  352.     is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
  353.     is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
  354.  
  355.     ASSERT(is_left ^ is_right);
  356.     if (is_left) {
  357.         index = (frame_index(zone, frame)) +
  358.             (1 << frame->buddy_order);
  359.     } else {    /* if (is_right) */
  360.         index = (frame_index(zone, frame)) -
  361.             (1 << frame->buddy_order);
  362.     }
  363.    
  364.     if (frame_index_valid(zone, index)) {
  365.         if (zone->frames[index].buddy_order == frame->buddy_order &&
  366.             zone->frames[index].refcount == 0) {
  367.             return &zone->frames[index].buddy_link;
  368.         }
  369.     }
  370.  
  371.     return NULL;   
  372. }
  373.  
  374. /** Buddy system bisect implementation.
  375.  *
  376.  * @param b     Buddy system.
  377.  * @param block     Block to bisect.
  378.  *
  379.  * @return      Right block.
  380.  */
  381. static link_t *zone_buddy_bisect(buddy_system_t *b, link_t *block)
  382. {
  383.     frame_t *frame_l, *frame_r;
  384.  
  385.     frame_l = list_get_instance(block, frame_t, buddy_link);
  386.     frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
  387.    
  388.     return &frame_r->buddy_link;
  389. }
  390.  
  391. /** Buddy system coalesce implementation.
  392.  *
  393.  * @param b     Buddy system.
  394.  * @param block_1   First block.
  395.  * @param block_2   First block's buddy.
  396.  *
  397.  * @return      Coalesced block (actually block that represents lower
  398.  *          address).
  399.  */
  400. static link_t *zone_buddy_coalesce(buddy_system_t *b, link_t *block_1,
  401.     link_t *block_2)
  402. {
  403.     frame_t *frame1, *frame2;
  404.    
  405.     frame1 = list_get_instance(block_1, frame_t, buddy_link);
  406.     frame2 = list_get_instance(block_2, frame_t, buddy_link);
  407.    
  408.     return frame1 < frame2 ? block_1 : block_2;
  409. }
  410.  
  411. /** Buddy system set_order implementation.
  412.  *
  413.  * @param b     Buddy system.
  414.  * @param block     Buddy system block.
  415.  * @param order     Order to set.
  416.  */
  417. static void zone_buddy_set_order(buddy_system_t *b, link_t *block,
  418.     uint8_t order)
  419. {
  420.     frame_t *frame;
  421.     frame = list_get_instance(block, frame_t, buddy_link);
  422.     frame->buddy_order = order;
  423. }
  424.  
  425. /** Buddy system get_order implementation.
  426.  *
  427.  * @param b     Buddy system.
  428.  * @param block     Buddy system block.
  429.  *
  430.  * @return      Order of block.
  431.  */
  432. static uint8_t zone_buddy_get_order(buddy_system_t *b, link_t *block)
  433. {
  434.     frame_t *frame;
  435.     frame = list_get_instance(block, frame_t, buddy_link);
  436.     return frame->buddy_order;
  437. }
  438.  
  439. /** Buddy system mark_busy implementation.
  440.  *
  441.  * @param b     Buddy system.
  442.  * @param block     Buddy system block.
  443.  */
  444. static void zone_buddy_mark_busy(buddy_system_t *b, link_t * block)
  445. {
  446.     frame_t * frame;
  447.  
  448.     frame = list_get_instance(block, frame_t, buddy_link);
  449.     frame->refcount = 1;
  450. }
  451.  
  452. /** Buddy system mark_available implementation.
  453.  *
  454.  * @param b     Buddy system.
  455.  * @param block     Buddy system block.
  456.  */
  457. static void zone_buddy_mark_available(buddy_system_t *b, link_t *block)
  458. {
  459.     frame_t *frame;
  460.     frame = list_get_instance(block, frame_t, buddy_link);
  461.     frame->refcount = 0;
  462. }
  463.  
  464. static buddy_system_operations_t zone_buddy_system_operations = {
  465.     .find_buddy = zone_buddy_find_buddy,
  466.     .bisect = zone_buddy_bisect,
  467.     .coalesce = zone_buddy_coalesce,
  468.     .set_order = zone_buddy_set_order,
  469.     .get_order = zone_buddy_get_order,
  470.     .mark_busy = zone_buddy_mark_busy,
  471.     .mark_available = zone_buddy_mark_available,
  472.     .find_block = zone_buddy_find_block,
  473.     .print_id = zone_buddy_print_id
  474. };
  475.  
  476. /******************/
  477. /* Zone functions */
  478. /******************/
  479.  
  480. /** Allocate frame in particular zone.
  481.  *
  482.  * Assume zone is locked.
  483.  * Panics if allocation is impossible.
  484.  *
  485.  * @param zone      Zone to allocate from.
  486.  * @param order     Allocate exactly 2^order frames.
  487.  *
  488.  * @return      Frame index in zone.
  489.  *
  490.  */
  491. static pfn_t zone_frame_alloc(zone_t *zone, uint8_t order)
  492. {
  493.     pfn_t v;
  494.     link_t *tmp;
  495.     frame_t *frame;
  496.  
  497.     /* Allocate frames from zone buddy system */
  498.     tmp = buddy_system_alloc(zone->buddy_system, order);
  499.    
  500.     ASSERT(tmp);
  501.    
  502.     /* Update zone information. */
  503.     zone->free_count -= (1 << order);
  504.     zone->busy_count += (1 << order);
  505.  
  506.     /* Frame will be actually a first frame of the block. */
  507.     frame = list_get_instance(tmp, frame_t, buddy_link);
  508.    
  509.     /* get frame address */
  510.     v = make_frame_index(zone, frame);
  511.     return v;
  512. }
  513.  
  514. /** Free frame from zone.
  515.  *
  516.  * Assume zone is locked.
  517.  *
  518.  * @param zone      Pointer to zone from which the frame is to be freed.
  519.  * @param frame_idx Frame index relative to zone.
  520.  */
  521. static void zone_frame_free(zone_t *zone, index_t frame_idx)
  522. {
  523.     frame_t *frame;
  524.     uint8_t order;
  525.  
  526.     frame = &zone->frames[frame_idx];
  527.    
  528.     /* remember frame order */
  529.     order = frame->buddy_order;
  530.  
  531.     ASSERT(frame->refcount);
  532.  
  533.     if (!--frame->refcount) {
  534.         buddy_system_free(zone->buddy_system, &frame->buddy_link);
  535.    
  536.         /* Update zone information. */
  537.         zone->free_count += (1 << order);
  538.         zone->busy_count -= (1 << order);
  539.     }
  540. }
  541.  
  542. /** Return frame from zone. */
  543. static frame_t *zone_get_frame(zone_t *zone, index_t frame_idx)
  544. {
  545.     ASSERT(frame_idx < zone->count);
  546.     return &zone->frames[frame_idx];
  547. }
  548.  
  549. /** Mark frame in zone unavailable to allocation. */
  550. static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)
  551. {
  552.     frame_t *frame;
  553.     link_t *link;
  554.  
  555.     frame = zone_get_frame(zone, frame_idx);
  556.     if (frame->refcount)
  557.         return;
  558.     link = buddy_system_alloc_block(zone->buddy_system,
  559.         &frame->buddy_link);
  560.     ASSERT(link);
  561.     zone->free_count--;
  562.  
  563.     mutex_lock(&mem_avail_mtx);
  564.     mem_avail_frames--;
  565.     mutex_unlock(&mem_avail_mtx);
  566. }
  567.  
  568. /** Join two zones.
  569.  *
  570.  * Expect zone_t *z to point to space at least zone_conf_size large.
  571.  *
  572.  * Assume z1 & z2 are locked.
  573.  *
  574.  * @param z     Target zone structure pointer.
  575.  * @param z1        Zone to merge.
  576.  * @param z2        Zone to merge.
  577.  */
  578. static void _zone_merge(zone_t *z, zone_t *z1, zone_t *z2)
  579. {
  580.     uint8_t max_order;
  581.     unsigned int i;
  582.     int z2idx;
  583.     pfn_t frame_idx;
  584.     frame_t *frame;
  585.  
  586.     ASSERT(!overlaps(z1->base, z1->count, z2->base, z2->count));
  587.     ASSERT(z1->base < z2->base);
  588.  
  589.     spinlock_initialize(&z->lock, "zone_lock");
  590.     z->base = z1->base;
  591.     z->count = z2->base + z2->count - z1->base;
  592.     z->flags = z1->flags & z2->flags;
  593.  
  594.     z->free_count = z1->free_count + z2->free_count;
  595.     z->busy_count = z1->busy_count + z2->busy_count;
  596.    
  597.     max_order = fnzb(z->count);
  598.  
  599.     z->buddy_system = (buddy_system_t *) &z[1];
  600.     buddy_system_create(z->buddy_system, max_order,
  601.         &zone_buddy_system_operations, (void *) z);
  602.  
  603.     z->frames = (frame_t *)((uint8_t *) z->buddy_system +
  604.         buddy_conf_size(max_order));
  605.     for (i = 0; i < z->count; i++) {
  606.         /* This marks all frames busy */
  607.         frame_initialize(&z->frames[i]);
  608.     }
  609.     /* Copy frames from both zones to preserve full frame orders,
  610.      * parents etc. Set all free frames with refcount=0 to 1, because
  611.      * we add all free frames to buddy allocator later again, clear
  612.      * order to 0. Don't set busy frames with refcount=0, as they
  613.      * will not be reallocated during merge and it would make later
  614.      * problems with allocation/free.
  615.      */
  616.     for (i = 0; i < z1->count; i++)
  617.         z->frames[i] = z1->frames[i];
  618.     for (i = 0; i < z2->count; i++) {
  619.         z2idx = i + (z2->base - z1->base);
  620.         z->frames[z2idx] = z2->frames[i];
  621.     }
  622.     i = 0;
  623.     while (i < z->count) {
  624.         if (z->frames[i].refcount) {
  625.             /* skip busy frames */
  626.             i += 1 << z->frames[i].buddy_order;
  627.         } else { /* Free frames, set refcount=1 */
  628.             /* All free frames have refcount=0, we need not
  629.              * to check the order */
  630.             z->frames[i].refcount = 1;
  631.             z->frames[i].buddy_order = 0;
  632.             i++;
  633.         }
  634.     }
  635.     /* Add free blocks from the 2 original zones */
  636.     while (zone_can_alloc(z1, 0)) {
  637.         frame_idx = zone_frame_alloc(z1, 0);
  638.         frame = &z->frames[frame_idx];
  639.         frame->refcount = 0;
  640.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  641.     }
  642.     while (zone_can_alloc(z2, 0)) {
  643.         frame_idx = zone_frame_alloc(z2, 0);
  644.         frame = &z->frames[frame_idx + (z2->base - z1->base)];
  645.         frame->refcount = 0;
  646.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  647.     }
  648. }
  649.  
  650. /** Return old configuration frames into the zone.
  651.  *
  652.  * We have several cases
  653.  * - the conf. data is outside of zone -> exit, shall we call frame_free??
  654.  * - the conf. data was created by zone_create or
  655.  *   updated with reduce_region -> free every frame
  656.  *
  657.  * @param newzone   The actual zone where freeing should occur.
  658.  * @param oldzone   Pointer to old zone configuration data that should
  659.  *          be freed from new zone.
  660.  */
  661. static void return_config_frames(zone_t *newzone, zone_t *oldzone)
  662. {
  663.     pfn_t pfn;
  664.     frame_t *frame;
  665.     count_t cframes;
  666.     unsigned int i;
  667.  
  668.     pfn = ADDR2PFN((uintptr_t)KA2PA(oldzone));
  669.     cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
  670.    
  671.     if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
  672.         return;
  673.  
  674.     frame = &newzone->frames[pfn - newzone->base];
  675.     ASSERT(!frame->buddy_order);
  676.  
  677.     for (i = 0; i < cframes; i++) {
  678.         newzone->busy_count++;
  679.         zone_frame_free(newzone, pfn+i-newzone->base);
  680.     }
  681. }
  682.  
  683. /** Reduce allocated block to count of order 0 frames.
  684.  *
  685.  * The allocated block need 2^order frames of space. Reduce all frames
  686.  * in block to order 0 and free the unneeded frames. This means, that
  687.  * when freeing the previously allocated block starting with frame_idx,
  688.  * you have to free every frame.
  689.  *
  690.  * @param zone
  691.  * @param frame_idx     Index to block.
  692.  * @param count         Allocated space in block.
  693.  */
  694. static void zone_reduce_region(zone_t *zone, pfn_t frame_idx, count_t count)
  695. {
  696.     count_t i;
  697.     uint8_t order;
  698.     frame_t *frame;
  699.    
  700.     ASSERT(frame_idx + count < zone->count);
  701.  
  702.     order = zone->frames[frame_idx].buddy_order;
  703.     ASSERT((count_t) (1 << order) >= count);
  704.  
  705.     /* Reduce all blocks to order 0 */
  706.     for (i = 0; i < (count_t) (1 << order); i++) {
  707.         frame = &zone->frames[i + frame_idx];
  708.         frame->buddy_order = 0;
  709.         if (!frame->refcount)
  710.             frame->refcount = 1;
  711.         ASSERT(frame->refcount == 1);
  712.     }
  713.     /* Free unneeded frames */
  714.     for (i = count; i < (count_t) (1 << order); i++) {
  715.         zone_frame_free(zone, i + frame_idx);
  716.     }
  717. }
  718.  
  719. /** Merge zones z1 and z2.
  720.  *
  721.  * - the zones must be 2 zones with no zone existing in between,
  722.  *   which means that z2 = z1+1
  723.  *
  724.  * - When you create a new zone, the frame allocator configuration does
  725.  *   not to be 2^order size. Once the allocator is running it is no longer
  726.  *   possible, merged configuration data occupies more space :-/
  727.  */
  728. void zone_merge(unsigned int z1, unsigned int z2)
  729. {
  730.     ipl_t ipl;
  731.     zone_t *zone1, *zone2, *newzone;
  732.     unsigned int cframes;
  733.     uint8_t order;
  734.     unsigned int i;
  735.     pfn_t pfn;
  736.  
  737.     ipl = interrupts_disable();
  738.     spinlock_lock(&zones.lock);
  739.  
  740.     if ((z1 >= zones.count) || (z2 >= zones.count))
  741.         goto errout;
  742.     /* We can join only 2 zones with none existing inbetween */
  743.     if (z2 - z1 != 1)
  744.         goto errout;
  745.  
  746.     zone1 = zones.info[z1];
  747.     zone2 = zones.info[z2];
  748.     spinlock_lock(&zone1->lock);
  749.     spinlock_lock(&zone2->lock);
  750.  
  751.     cframes = SIZE2FRAMES(zone_conf_size(zone2->base + zone2->count -
  752.         zone1->base));
  753.     if (cframes == 1)
  754.         order = 0;
  755.     else
  756.         order = fnzb(cframes - 1) + 1;
  757.  
  758.     /* Allocate zonedata inside one of the zones */
  759.     if (zone_can_alloc(zone1, order))
  760.         pfn = zone1->base + zone_frame_alloc(zone1, order);
  761.     else if (zone_can_alloc(zone2, order))
  762.         pfn = zone2->base + zone_frame_alloc(zone2, order);
  763.     else
  764.         goto errout2;
  765.  
  766.     newzone = (zone_t *) PA2KA(PFN2ADDR(pfn));
  767.  
  768.     _zone_merge(newzone, zone1, zone2);
  769.  
  770.     /* Free unneeded config frames */
  771.     zone_reduce_region(newzone, pfn - newzone->base,  cframes);
  772.     /* Subtract zone information from busy frames */
  773.     newzone->busy_count -= cframes;
  774.  
  775.     /* Replace existing zones in zoneinfo list */
  776.     zones.info[z1] = newzone;
  777.     for (i = z2 + 1; i < zones.count; i++)
  778.         zones.info[i - 1] = zones.info[i];
  779.     zones.count--;
  780.  
  781.     /* Free old zone information */
  782.     return_config_frames(newzone, zone1);
  783.     return_config_frames(newzone, zone2);
  784. errout2:
  785.     /* Nobody is allowed to enter to zone, so we are safe
  786.      * to touch the spinlocks last time */
  787.     spinlock_unlock(&zone1->lock);
  788.     spinlock_unlock(&zone2->lock);
  789. errout:
  790.     spinlock_unlock(&zones.lock);
  791.     interrupts_restore(ipl);
  792. }
  793.  
  794. /** Merge all zones into one big zone.
  795.  *
  796.  * It is reasonable to do this on systems whose bios reports parts in chunks,
  797.  * so that we could have 1 zone (it's faster).
  798.  */
  799. void zone_merge_all(void)
  800. {
  801.     int count = zones.count;
  802.  
  803.     while (zones.count > 1 && --count) {
  804.         zone_merge(0, 1);
  805.         break;
  806.     }
  807. }
  808.  
  809. /** Create new frame zone.
  810.  *
  811.  * @param start     Physical address of the first frame within the zone.
  812.  * @param count     Count of frames in zone.
  813.  * @param z     Address of configuration information of zone.
  814.  * @param flags     Zone flags.
  815.  *
  816.  * @return      Initialized zone.
  817.  */
  818. static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
  819. {
  820.     unsigned int i;
  821.     uint8_t max_order;
  822.  
  823.     spinlock_initialize(&z->lock, "zone_lock");
  824.     z->base = start;
  825.     z->count = count;
  826.     z->flags = flags;
  827.     z->free_count = count;
  828.     z->busy_count = 0;
  829.  
  830.     /*
  831.      * Compute order for buddy system, initialize
  832.      */
  833.     max_order = fnzb(count);
  834.     z->buddy_system = (buddy_system_t *)&z[1];
  835.    
  836.     buddy_system_create(z->buddy_system, max_order,
  837.         &zone_buddy_system_operations, (void *) z);
  838.    
  839.     /* Allocate frames _after_ the conframe */
  840.     /* Check sizes */
  841.     z->frames = (frame_t *)((uint8_t *) z->buddy_system +
  842.         buddy_conf_size(max_order));
  843.     for (i = 0; i < count; i++) {
  844.         frame_initialize(&z->frames[i]);
  845.     }
  846.    
  847.     /* Stuffing frames */
  848.     for (i = 0; i < count; i++) {
  849.         z->frames[i].refcount = 0;
  850.         buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
  851.     }
  852. }
  853.  
  854. /** Compute configuration data size for zone.
  855.  *
  856.  * @param count     Size of zone in frames.
  857.  * @return      Size of zone configuration info (in bytes).
  858.  */
  859. uintptr_t zone_conf_size(count_t count)
  860. {
  861.     int size = sizeof(zone_t) + count * sizeof(frame_t);
  862.     int max_order;
  863.  
  864.     max_order = fnzb(count);
  865.     size += buddy_conf_size(max_order);
  866.     return size;
  867. }
  868.  
  869. /** Create and add zone to system.
  870.  *
  871.  * @param start     First frame number (absolute).
  872.  * @param count     Size of zone in frames.
  873.  * @param confframe Where configuration frames are supposed to be.
  874.  *          Automatically checks, that we will not disturb the
  875.  *          kernel and possibly init.  If confframe is given
  876.  *          _outside_ this zone, it is expected, that the area is
  877.  *          already marked BUSY and big enough to contain
  878.  *          zone_conf_size() amount of data.  If the confframe is
  879.  *          inside the area, the zone free frame information is
  880.  *          modified not to include it.
  881.  *
  882.  * @return      Zone number or -1 on error.
  883.  */
  884. int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
  885. {
  886.     zone_t *z;
  887.     uintptr_t addr;
  888.     count_t confcount;
  889.     unsigned int i;
  890.     int znum;
  891.  
  892.     /* Theoretically we could have here 0, practically make sure
  893.      * nobody tries to do that. If some platform requires, remove
  894.      * the assert
  895.      */
  896.     ASSERT(confframe);
  897.     /* If conframe is supposed to be inside our zone, then make sure
  898.      * it does not span kernel & init
  899.      */
  900.     confcount = SIZE2FRAMES(zone_conf_size(count));
  901.     if (confframe >= start && confframe < start + count) {
  902.         for (; confframe < start + count; confframe++) {
  903.             addr = PFN2ADDR(confframe);
  904.             if (overlaps(addr, PFN2ADDR(confcount),
  905.                 KA2PA(config.base), config.kernel_size))
  906.                 continue;
  907.            
  908.             if (overlaps(addr, PFN2ADDR(confcount),
  909.                 KA2PA(config.stack_base), config.stack_size))
  910.                 continue;
  911.            
  912.             bool overlap = false;
  913.             count_t i;
  914.             for (i = 0; i < init.cnt; i++)
  915.                 if (overlaps(addr, PFN2ADDR(confcount),
  916.                     KA2PA(init.tasks[i].addr),
  917.                     init.tasks[i].size)) {
  918.                     overlap = true;
  919.                     break;
  920.                 }
  921.             if (overlap)
  922.                 continue;
  923.            
  924.             break;
  925.         }
  926.         if (confframe >= start + count)
  927.             panic("Cannot find configuration data for zone.");
  928.     }
  929.  
  930.     z = (zone_t *) PA2KA(PFN2ADDR(confframe));
  931.     zone_construct(start, count, z, flags);
  932.     znum = zones_add_zone(z);
  933.     if (znum == -1)
  934.         return -1;
  935.  
  936.     mutex_lock(&mem_avail_mtx);
  937.     mem_avail_frames += count;
  938.     mutex_unlock(&mem_avail_mtx);
  939.  
  940.     /* If confdata in zone, mark as unavailable */
  941.     if (confframe >= start && confframe < start + count)
  942.         for (i = confframe; i < confframe + confcount; i++) {
  943.             zone_mark_unavailable(z, i - z->base);
  944.         }
  945.    
  946.     return znum;
  947. }
  948.  
  949. /***************************************/
  950. /* Frame functions */
  951.  
  952. /** Set parent of frame. */
  953. void frame_set_parent(pfn_t pfn, void *data, unsigned int hint)
  954. {
  955.     zone_t *zone = find_zone_and_lock(pfn, &hint);
  956.  
  957.     ASSERT(zone);
  958.  
  959.     zone_get_frame(zone, pfn - zone->base)->parent = data;
  960.     spinlock_unlock(&zone->lock);
  961. }
  962.  
  963. void *frame_get_parent(pfn_t pfn, unsigned int hint)
  964. {
  965.     zone_t *zone = find_zone_and_lock(pfn, &hint);
  966.     void *res;
  967.  
  968.     ASSERT(zone);
  969.     res = zone_get_frame(zone, pfn - zone->base)->parent;
  970.    
  971.     spinlock_unlock(&zone->lock);
  972.     return res;
  973. }
  974.  
  975. /** Allocate power-of-two frames of physical memory.
  976.  *
  977.  * @param order     Allocate exactly 2^order frames.
  978.  * @param flags     Flags for host zone selection and address processing.
  979.  * @param pzone     Preferred zone.
  980.  *
  981.  * @return      Physical address of the allocated frame.
  982.  *
  983.  */
  984. void *frame_alloc_generic(uint8_t order, int flags, unsigned int *pzone)
  985. {
  986.     ipl_t ipl;
  987.     int freed;
  988.     pfn_t v;
  989.     zone_t *zone;
  990.     unsigned long gen = 0;
  991.    
  992. loop:
  993.     ipl = interrupts_disable();
  994.    
  995.     /*
  996.      * First, find suitable frame zone.
  997.      */
  998.     zone = find_free_zone_and_lock(order, pzone);
  999.    
  1000.     /* If no memory, reclaim some slab memory,
  1001.        if it does not help, reclaim all */
  1002.     if (!zone && !(flags & FRAME_NO_RECLAIM)) {
  1003.         freed = slab_reclaim(0);
  1004.         if (freed)
  1005.             zone = find_free_zone_and_lock(order, pzone);
  1006.         if (!zone) {
  1007.             freed = slab_reclaim(SLAB_RECLAIM_ALL);
  1008.             if (freed)
  1009.                 zone = find_free_zone_and_lock(order, pzone);
  1010.         }
  1011.     }
  1012.     if (!zone) {
  1013.         /*
  1014.          * Sleep until some frames are available again.
  1015.          */
  1016.         if (flags & FRAME_ATOMIC) {
  1017.             interrupts_restore(ipl);
  1018.             return 0;
  1019.         }
  1020.        
  1021. #ifdef CONFIG_DEBUG
  1022.         unsigned long avail;
  1023.  
  1024.         mutex_lock(&mem_avail_mtx);
  1025.         avail = mem_avail_frames;
  1026.         mutex_unlock(&mem_avail_mtx);
  1027.  
  1028.         printf("Thread %" PRIu64 " waiting for %u frames, "
  1029.             "%u available.\n", THREAD->tid, 1ULL << order, avail);
  1030. #endif
  1031.  
  1032.         mutex_lock(&mem_avail_mtx);
  1033.         while ((mem_avail_frames < (1ULL << order)) ||
  1034.             gen == mem_avail_gen)
  1035.             condvar_wait(&mem_avail_cv, &mem_avail_mtx);
  1036.         gen = mem_avail_gen;
  1037.         mutex_unlock(&mem_avail_mtx);
  1038.  
  1039. #ifdef CONFIG_DEBUG
  1040.         mutex_lock(&mem_avail_mtx);
  1041.         avail = mem_avail_frames;
  1042.         mutex_unlock(&mem_avail_mtx);
  1043.  
  1044.         printf("Thread %" PRIu64 " woken up, %u frames available.\n",
  1045.             THREAD->tid, avail);
  1046. #endif
  1047.  
  1048.         interrupts_restore(ipl);
  1049.         goto loop;
  1050.     }
  1051.    
  1052.     v = zone_frame_alloc(zone, order);
  1053.     v += zone->base;
  1054.  
  1055.     spinlock_unlock(&zone->lock);
  1056.    
  1057.     mutex_lock(&mem_avail_mtx);
  1058.     mem_avail_frames -= (1ULL << order);
  1059.     mutex_unlock(&mem_avail_mtx);
  1060.  
  1061.     interrupts_restore(ipl);
  1062.  
  1063.     if (flags & FRAME_KA)
  1064.         return (void *)PA2KA(PFN2ADDR(v));
  1065.     return (void *)PFN2ADDR(v);
  1066. }
  1067.  
  1068. /** Free a frame.
  1069.  *
  1070.  * Find respective frame structure for supplied physical frame address.
  1071.  * Decrement frame reference count.
  1072.  * If it drops to zero, move the frame structure to free list.
  1073.  *
  1074.  * @param frame     Physical Address of of the frame to be freed.
  1075.  */
  1076. void frame_free(uintptr_t frame)
  1077. {
  1078.     ipl_t ipl;
  1079.     zone_t *zone;
  1080.     pfn_t pfn = ADDR2PFN(frame);
  1081.  
  1082.     ipl = interrupts_disable();
  1083.  
  1084.     /*
  1085.      * First, find host frame zone for addr.
  1086.      */
  1087.     zone = find_zone_and_lock(pfn, NULL);
  1088.     ASSERT(zone);
  1089.    
  1090.     zone_frame_free(zone, pfn - zone->base);
  1091.    
  1092.     spinlock_unlock(&zone->lock);
  1093.    
  1094.     /*
  1095.      * Signal that some memory has been freed.
  1096.      */
  1097.     mutex_lock(&mem_avail_mtx);
  1098.     mem_avail_frames++;
  1099.     mem_avail_gen++;
  1100.     condvar_broadcast(&mem_avail_cv);
  1101.     mutex_unlock(&mem_avail_mtx);
  1102.  
  1103.     interrupts_restore(ipl);
  1104. }
  1105.  
  1106. /** Add reference to frame.
  1107.  *
  1108.  * Find respective frame structure for supplied PFN and
  1109.  * increment frame reference count.
  1110.  *
  1111.  * @param pfn       Frame number of the frame to be freed.
  1112.  */
  1113. void frame_reference_add(pfn_t pfn)
  1114. {
  1115.     ipl_t ipl;
  1116.     zone_t *zone;
  1117.     frame_t *frame;
  1118.  
  1119.     ipl = interrupts_disable();
  1120.    
  1121.     /*
  1122.      * First, find host frame zone for addr.
  1123.      */
  1124.     zone = find_zone_and_lock(pfn, NULL);
  1125.     ASSERT(zone);
  1126.    
  1127.     frame = &zone->frames[pfn - zone->base];
  1128.     frame->refcount++;
  1129.    
  1130.     spinlock_unlock(&zone->lock);
  1131.     interrupts_restore(ipl);
  1132. }
  1133.  
  1134. /** Mark given range unavailable in frame zones. */
  1135. void frame_mark_unavailable(pfn_t start, count_t count)
  1136. {
  1137.     unsigned int i;
  1138.     zone_t *zone;
  1139.     unsigned int prefzone = 0;
  1140.    
  1141.     for (i = 0; i < count; i++) {
  1142.         zone = find_zone_and_lock(start + i, &prefzone);
  1143.         if (!zone) /* PFN not found */
  1144.             continue;
  1145.         zone_mark_unavailable(zone, start + i - zone->base);
  1146.  
  1147.         spinlock_unlock(&zone->lock);
  1148.     }
  1149. }
  1150.  
  1151. /** Initialize physical memory management. */
  1152. void frame_init(void)
  1153. {
  1154.     if (config.cpu_active == 1) {
  1155.         zones.count = 0;
  1156.         spinlock_initialize(&zones.lock, "zones.lock");
  1157.         mutex_initialize(&mem_avail_mtx, MUTEX_ACTIVE);
  1158.         condvar_initialize(&mem_avail_cv);
  1159.     }
  1160.     /* Tell the architecture to create some memory */
  1161.     frame_arch_init();
  1162.     if (config.cpu_active == 1) {
  1163.         frame_mark_unavailable(ADDR2PFN(KA2PA(config.base)),
  1164.             SIZE2FRAMES(config.kernel_size));
  1165.         frame_mark_unavailable(ADDR2PFN(KA2PA(config.stack_base)),
  1166.             SIZE2FRAMES(config.stack_size));
  1167.        
  1168.         count_t i;
  1169.         for (i = 0; i < init.cnt; i++) {
  1170.             pfn_t pfn = ADDR2PFN(KA2PA(init.tasks[i].addr));
  1171.             frame_mark_unavailable(pfn,
  1172.                 SIZE2FRAMES(init.tasks[i].size));
  1173.         }
  1174.  
  1175.         if (ballocs.size)
  1176.             frame_mark_unavailable(ADDR2PFN(KA2PA(ballocs.base)),
  1177.                 SIZE2FRAMES(ballocs.size));
  1178.  
  1179.         /* Black list first frame, as allocating NULL would
  1180.          * fail in some places */
  1181.         frame_mark_unavailable(0, 1);
  1182.     }
  1183. }
  1184.  
  1185.  
  1186. /** Return total size of all zones. */
  1187. uint64_t zone_total_size(void)
  1188. {
  1189.     zone_t *zone = NULL;
  1190.     unsigned int i;
  1191.     ipl_t ipl;
  1192.     uint64_t total = 0;
  1193.  
  1194.     ipl = interrupts_disable();
  1195.     spinlock_lock(&zones.lock);
  1196.    
  1197.     for (i = 0; i < zones.count; i++) {
  1198.         zone = zones.info[i];
  1199.         spinlock_lock(&zone->lock);
  1200.         total += (uint64_t) FRAMES2SIZE(zone->count);
  1201.         spinlock_unlock(&zone->lock);
  1202.     }
  1203.    
  1204.     spinlock_unlock(&zones.lock);
  1205.     interrupts_restore(ipl);
  1206.    
  1207.     return total;
  1208. }
  1209.  
  1210. /** Prints list of zones. */
  1211. void zone_print_list(void)
  1212. {
  1213.     zone_t *zone = NULL;
  1214.     unsigned int i;
  1215.     ipl_t ipl;
  1216.  
  1217.     ipl = interrupts_disable();
  1218.     spinlock_lock(&zones.lock);
  1219.  
  1220. #ifdef __32_BITS__ 
  1221.     printf("#  base address free frames  busy frames\n");
  1222.     printf("-- ------------ ------------ ------------\n");
  1223. #endif
  1224.  
  1225. #ifdef __64_BITS__
  1226.     printf("#  base address         free frames  busy frames\n");
  1227.     printf("-- -------------------- ------------ ------------\n");
  1228. #endif
  1229.    
  1230.     for (i = 0; i < zones.count; i++) {
  1231.         zone = zones.info[i];
  1232.         spinlock_lock(&zone->lock);
  1233.  
  1234. #ifdef __32_BITS__
  1235.         printf("%-2u   %10p %12" PRIc " %12" PRIc "\n",
  1236.             i, PFN2ADDR(zone->base), zone->free_count,
  1237.             zone->busy_count);
  1238. #endif
  1239.  
  1240. #ifdef __64_BITS__
  1241.         printf("%-2u   %18p %12" PRIc " %12" PRIc "\n", i,
  1242.             PFN2ADDR(zone->base), zone->free_count, zone->busy_count);
  1243. #endif
  1244.        
  1245.         spinlock_unlock(&zone->lock);
  1246.     }
  1247.    
  1248.     spinlock_unlock(&zones.lock);
  1249.     interrupts_restore(ipl);
  1250. }
  1251.  
  1252. /** Prints zone details.
  1253.  *
  1254.  * @param num       Zone base address or zone number.
  1255.  */
  1256. void zone_print_one(unsigned int num)
  1257. {
  1258.     zone_t *zone = NULL;
  1259.     ipl_t ipl;
  1260.     unsigned int i;
  1261.  
  1262.     ipl = interrupts_disable();
  1263.     spinlock_lock(&zones.lock);
  1264.  
  1265.     for (i = 0; i < zones.count; i++) {
  1266.         if ((i == num) || (PFN2ADDR(zones.info[i]->base) == num)) {
  1267.             zone = zones.info[i];
  1268.             break;
  1269.         }
  1270.     }
  1271.     if (!zone) {
  1272.         printf("Zone not found.\n");
  1273.         goto out;
  1274.     }
  1275.    
  1276.     spinlock_lock(&zone->lock);
  1277.     printf("Memory zone information\n");
  1278.     printf("Zone base address: %p\n", PFN2ADDR(zone->base));
  1279.     printf("Zone size: %" PRIc " frames (%" PRIs " KB)\n", zone->count,
  1280.         SIZE2KB(FRAMES2SIZE(zone->count)));
  1281.     printf("Allocated space: %" PRIc " frames (%" PRIs " KB)\n",
  1282.         zone->busy_count, SIZE2KB(FRAMES2SIZE(zone->busy_count)));
  1283.     printf("Available space: %" PRIc " frames (%" PRIs " KB)\n",
  1284.         zone->free_count, SIZE2KB(FRAMES2SIZE(zone->free_count)));
  1285.     buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
  1286.     spinlock_unlock(&zone->lock);
  1287.    
  1288. out:
  1289.     spinlock_unlock(&zones.lock);
  1290.     interrupts_restore(ipl);
  1291. }
  1292.  
  1293. /** @}
  1294.  */
  1295.  
  1296.