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  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. /*
  31.  * Locking order
  32.  *
  33.  * In order to access particular zone, the process must first lock
  34.  * the zones.lock, then lock the zone and then unlock the zones.lock.
  35.  * This insures, that we can fiddle with the zones in runtime without
  36.  * affecting the processes.
  37.  *
  38.  */
  39.  
  40. #include <typedefs.h>
  41. #include <arch/types.h>
  42. #include <mm/frame.h>
  43. #include <mm/as.h>
  44. #include <panic.h>
  45. #include <debug.h>
  46. #include <adt/list.h>
  47. #include <synch/spinlock.h>
  48. #include <arch/asm.h>
  49. #include <arch.h>
  50. #include <print.h>
  51. #include <align.h>
  52. #include <mm/slab.h>
  53. #include <bitops.h>
  54.  
  55. typedef struct {
  56.     count_t refcount;   /**< tracking of shared frames  */
  57.     __u8 buddy_order;   /**< buddy system block order */
  58.     link_t buddy_link;  /**< link to the next free block inside one order */
  59.     void *parent;           /**< If allocated by slab, this points there */
  60. }frame_t;
  61.  
  62. typedef struct {
  63.     SPINLOCK_DECLARE(lock); /**< this lock protects everything below */
  64.     pfn_t base; /**< frame_no of the first frame in the frames array */
  65.     count_t count;          /**< Size of zone */
  66.  
  67.     frame_t *frames;    /**< array of frame_t structures in this zone */
  68.     count_t free_count; /**< number of free frame_t structures */
  69.     count_t busy_count; /**< number of busy frame_t structures */
  70.    
  71.     buddy_system_t * buddy_system; /**< buddy system for the zone */
  72.     int flags;
  73. }zone_t;
  74.  
  75. /*
  76.  * The zoneinfo.lock must be locked when accessing zoneinfo structure.
  77.  * Some of the attributes in zone_t structures are 'read-only'
  78.  */
  79.  
  80. struct {
  81.     SPINLOCK_DECLARE(lock);
  82.     int count;
  83.     zone_t *info[ZONES_MAX];
  84. }zones;
  85.  
  86.  
  87. /*********************************/
  88. /* Helper functions */
  89. static inline index_t frame_index(zone_t *zone, frame_t *frame)
  90. {
  91.     return (index_t)(frame - zone->frames);
  92. }
  93. static inline index_t frame_index_abs(zone_t *zone, frame_t *frame)
  94. {
  95.     return (index_t)(frame - zone->frames) + zone->base;
  96. }
  97. static inline int frame_index_valid(zone_t *zone, index_t index)
  98. {
  99.     return index >= 0 && index < zone->count;
  100. }
  101.  
  102. /** Compute pfn_t from frame_t pointer & zone pointer */
  103. static index_t make_frame_index(zone_t *zone, frame_t *frame)
  104. {
  105.     return frame - zone->frames;
  106. }
  107.  
  108. /** Initialize frame structure
  109.  *
  110.  * Initialize frame structure.
  111.  *
  112.  * @param frame Frame structure to be initialized.
  113.  */
  114. static void frame_initialize(frame_t *frame)
  115. {
  116.     frame->refcount = 1;
  117.     frame->buddy_order = 0;
  118. }
  119.  
  120. /*************************************/
  121. /* Zoneinfo functions */
  122.  
  123. /**
  124.  * Insert-sort zone into zones list
  125.  *
  126.  * @return zone number on success, -1 on error
  127.  */
  128. static int zones_add_zone(zone_t *newzone)
  129. {
  130.     int i,j;
  131.     ipl_t ipl;
  132.     zone_t *z;
  133.  
  134.     ipl = interrupts_disable();
  135.     spinlock_lock(&zones.lock);
  136.     /* Try to merge */
  137.     if (zones.count+1 == ZONES_MAX)
  138.         panic("Maximum zone(%d) count exceeded.", ZONES_MAX);
  139.  
  140.     for (i=0; i < zones.count; i++) {
  141.         /* Check for overflow */
  142.         z = zones.info[zones.count];
  143.         if (overlaps(newzone->base,newzone->count,
  144.                  z->base, z->count)) {
  145.             printf("Zones overlap!\n");
  146.             return -1;
  147.         }
  148.         if (z->base < newzone->base)
  149.             break;
  150.     }
  151.     /* Move other zones up */
  152.     for (j=i;j < zones.count;j++)
  153.         zones.info[j+1] = zones.info[j];
  154.  
  155.     zones.info[i] = newzone;
  156.     zones.count++;
  157.  
  158.     spinlock_unlock(&zones.lock);
  159.     interrupts_restore(ipl);
  160.  
  161.     return i;
  162. }
  163.  
  164. /**
  165.  * Try to find a zone where can we find the frame
  166.  *
  167.  * @param hint Start searching in zone 'hint'
  168.  * @param lock Lock zone if true
  169.  *
  170.  * Assume interrupts disable
  171.  */
  172. static zone_t * find_zone_and_lock(pfn_t frame, int *pzone)
  173. {
  174.     int i;
  175.     int hint = pzone ? *pzone : 0;
  176.     zone_t *z;
  177.    
  178.     spinlock_lock(&zones.lock);
  179.  
  180.     if (hint >= zones.count || hint < 0)
  181.         hint = 0;
  182.    
  183.     i = hint;
  184.     do {
  185.         z = zones.info[i];
  186.         spinlock_lock(&z->lock);
  187.         if (z->base <= frame && z->base + z->count > frame) {
  188.             spinlock_unlock(&zones.lock); /* Unlock the global lock */
  189.             if (pzone)
  190.                 *pzone = i;
  191.             return z;
  192.         }
  193.         spinlock_unlock(&z->lock);
  194.  
  195.         i++;
  196.         if (i >= zones.count)
  197.             i = 0;
  198.     } while(i != hint);
  199.  
  200.     spinlock_unlock(&zones.lock);
  201.     return NULL;
  202. }
  203.  
  204. /** @return True if zone can allocate specified order */
  205. static int zone_can_alloc(zone_t *z, __u8 order)
  206. {
  207.     return buddy_system_can_alloc(z->buddy_system, order);
  208. }
  209.  
  210. /**
  211.  * Find AND LOCK zone that can allocate order frames
  212.  *
  213.  * Assume interrupts are disabled!!
  214.  *
  215.  * @param pzone Pointer to preferred zone or NULL, on return contains zone number
  216.  */
  217. static zone_t * find_free_zone_lock(__u8 order, int *pzone)
  218. {
  219.     int i;
  220.     zone_t *z;
  221.     int hint = pzone ? *pzone : 0;
  222.    
  223.     spinlock_lock(&zones.lock);
  224.     if (hint >= zones.count)
  225.         hint = 0;
  226.     i = hint;
  227.     do {
  228.         z = zones.info[i];
  229.        
  230.         spinlock_lock(&z->lock);
  231.  
  232.         /* Check if the zone has 2^order frames area available  */
  233.         if (zone_can_alloc(z, order)) {
  234.             spinlock_unlock(&zones.lock);
  235.             if (pzone)
  236.                 *pzone = i;
  237.             return z;
  238.         }
  239.         spinlock_unlock(&z->lock);
  240.         if (++i >= zones.count)
  241.             i = 0;
  242.     } while(i != hint);
  243.     spinlock_unlock(&zones.lock);
  244.     return NULL;
  245. }
  246.  
  247. /********************************************/
  248. /* Buddy system functions */
  249.  
  250. /** Buddy system find_block implementation
  251.  *
  252.  * Find block that is parent of current list.
  253.  * That means go to lower addresses, until such block is found
  254.  *
  255.  * @param order - Order of parent must be different then this parameter!!
  256.  */
  257. static link_t *zone_buddy_find_block(buddy_system_t *b, link_t *child,
  258.                      __u8 order)
  259. {
  260.     frame_t * frame;
  261.     zone_t * zone;
  262.     index_t index;
  263.    
  264.     frame = list_get_instance(child, frame_t, buddy_link);
  265.     zone = (zone_t *) b->data;
  266.  
  267.     index = frame_index(zone, frame);
  268.     do {
  269.         if (zone->frames[index].buddy_order != order) {
  270.             return &zone->frames[index].buddy_link;
  271.         }
  272.     } while(index-- > 0);
  273.     return NULL;
  274. }
  275.  
  276. static void zone_buddy_print_id(buddy_system_t *b, link_t *block)
  277. {
  278.     frame_t * frame;
  279.     zone_t * zone;
  280.     index_t index;
  281.  
  282.     frame = list_get_instance(block, frame_t, buddy_link);
  283.     zone = (zone_t *) b->data;
  284.     index = frame_index(zone, frame);
  285.     printf("%d", index);
  286. }                    
  287.  
  288. /** Buddy system find_buddy implementation
  289.  *
  290.  * @param b Buddy system.
  291.  * @param block Block for which buddy should be found
  292.  *
  293.  * @return Buddy for given block if found
  294.  */
  295. static link_t * zone_buddy_find_buddy(buddy_system_t *b, link_t * block)
  296. {
  297.     frame_t * frame;
  298.     zone_t * zone;
  299.     index_t index;
  300.     bool is_left, is_right;
  301.  
  302.     frame = list_get_instance(block, frame_t, buddy_link);
  303.     zone = (zone_t *) b->data;
  304.     ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame), frame->buddy_order));
  305.    
  306.     is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
  307.     is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
  308.  
  309.     ASSERT(is_left ^ is_right);
  310.     if (is_left) {
  311.         index = (frame_index(zone, frame)) + (1 << frame->buddy_order);
  312.     } else { // if (is_right)
  313.         index = (frame_index(zone, frame)) - (1 << frame->buddy_order);
  314.     }
  315.    
  316.  
  317.     if (frame_index_valid(zone, index)) {
  318.         if (zone->frames[index].buddy_order == frame->buddy_order &&
  319.             zone->frames[index].refcount == 0) {
  320.             return &zone->frames[index].buddy_link;
  321.         }
  322.     }
  323.  
  324.     return NULL;   
  325. }
  326.  
  327. /** Buddy system bisect implementation
  328.  *
  329.  * @param b Buddy system.
  330.  * @param block Block to bisect
  331.  *
  332.  * @return right block
  333.  */
  334. static link_t * zone_buddy_bisect(buddy_system_t *b, link_t * block) {
  335.     frame_t * frame_l, * frame_r;
  336.  
  337.     frame_l = list_get_instance(block, frame_t, buddy_link);
  338.     frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
  339.    
  340.     return &frame_r->buddy_link;
  341. }
  342.  
  343. /** Buddy system coalesce implementation
  344.  *
  345.  * @param b Buddy system.
  346.  * @param block_1 First block
  347.  * @param block_2 First block's buddy
  348.  *
  349.  * @return Coalesced block (actually block that represents lower address)
  350.  */
  351. static link_t * zone_buddy_coalesce(buddy_system_t *b, link_t * block_1,
  352.                     link_t * block_2)
  353. {
  354.     frame_t *frame1, *frame2;
  355.    
  356.     frame1 = list_get_instance(block_1, frame_t, buddy_link);
  357.     frame2 = list_get_instance(block_2, frame_t, buddy_link);
  358.    
  359.     return frame1 < frame2 ? block_1 : block_2;
  360. }
  361.  
  362. /** Buddy system set_order implementation
  363.  *
  364.  * @param b Buddy system.
  365.  * @param block Buddy system block
  366.  * @param order Order to set
  367.  */
  368. static void zone_buddy_set_order(buddy_system_t *b, link_t * block, __u8 order) {
  369.     frame_t * frame;
  370.     frame = list_get_instance(block, frame_t, buddy_link);
  371.     frame->buddy_order = order;
  372. }
  373.  
  374. /** Buddy system get_order implementation
  375.  *
  376.  * @param b Buddy system.
  377.  * @param block Buddy system block
  378.  *
  379.  * @return Order of block
  380.  */
  381. static __u8 zone_buddy_get_order(buddy_system_t *b, link_t * block) {
  382.     frame_t * frame;
  383.     frame = list_get_instance(block, frame_t, buddy_link);
  384.     return frame->buddy_order;
  385. }
  386.  
  387. /** Buddy system mark_busy implementation
  388.  *
  389.  * @param b Buddy system
  390.  * @param block Buddy system block
  391.  *
  392.  */
  393. static void zone_buddy_mark_busy(buddy_system_t *b, link_t * block) {
  394.     frame_t * frame;
  395.  
  396.     frame = list_get_instance(block, frame_t, buddy_link);
  397.     frame->refcount = 1;
  398. }
  399.  
  400. /** Buddy system mark_available implementation
  401.  *
  402.  * @param b Buddy system
  403.  * @param block Buddy system block
  404.  *
  405.  */
  406. static void zone_buddy_mark_available(buddy_system_t *b, link_t * block) {
  407.     frame_t * frame;
  408.     frame = list_get_instance(block, frame_t, buddy_link);
  409.     frame->refcount = 0;
  410. }
  411.  
  412. static struct buddy_system_operations  zone_buddy_system_operations = {
  413.     .find_buddy = zone_buddy_find_buddy,
  414.     .bisect = zone_buddy_bisect,
  415.     .coalesce = zone_buddy_coalesce,
  416.     .set_order = zone_buddy_set_order,
  417.     .get_order = zone_buddy_get_order,
  418.     .mark_busy = zone_buddy_mark_busy,
  419.     .mark_available = zone_buddy_mark_available,
  420.     .find_block = zone_buddy_find_block,
  421.     .print_id = zone_buddy_print_id
  422. };
  423.  
  424. /*************************************/
  425. /* Zone functions */
  426.  
  427. /** Allocate frame in particular zone
  428.  *
  429.  * Assume zone is locked
  430.  * Panics, if allocation is impossible.
  431.  *
  432.  * @return Frame index in zone
  433.  */
  434. static pfn_t zone_frame_alloc(zone_t *zone,__u8 order)
  435. {
  436.     pfn_t v;
  437.     link_t *tmp;
  438.     frame_t *frame;
  439.  
  440.     /* Allocate frames from zone buddy system */
  441.     tmp = buddy_system_alloc(zone->buddy_system, order);
  442.    
  443.     ASSERT(tmp);
  444.    
  445.     /* Update zone information. */
  446.     zone->free_count -= (1 << order);
  447.     zone->busy_count += (1 << order);
  448.  
  449.     /* Frame will be actually a first frame of the block. */
  450.     frame = list_get_instance(tmp, frame_t, buddy_link);
  451.    
  452.     /* get frame address */
  453.     v = make_frame_index(zone, frame);
  454.     return v;
  455. }
  456.  
  457. /** Free frame from zone
  458.  *
  459.  * Assume zone is locked
  460.  */
  461. static void zone_frame_free(zone_t *zone, index_t frame_idx)
  462. {
  463.     frame_t *frame;
  464.     __u8 order;
  465.  
  466.     frame = &zone->frames[frame_idx];
  467.    
  468.     /* remember frame order */
  469.     order = frame->buddy_order;
  470.  
  471.     ASSERT(frame->refcount);
  472.  
  473.     if (!--frame->refcount) {
  474.         buddy_system_free(zone->buddy_system, &frame->buddy_link);
  475.     }
  476.  
  477.     /* Update zone information. */
  478.     zone->free_count += (1 << order);
  479.     zone->busy_count -= (1 << order);
  480. }
  481.  
  482. /** Return frame from zone */
  483. static frame_t * zone_get_frame(zone_t *zone, index_t frame_idx)
  484. {
  485.     ASSERT(frame_idx < zone->count);
  486.     return &zone->frames[frame_idx];
  487. }
  488.  
  489. /** Mark frame in zone unavailable to allocation */
  490. static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)
  491. {
  492.     frame_t *frame;
  493.     link_t *link;
  494.  
  495.     frame = zone_get_frame(zone, frame_idx);
  496.     if (frame->refcount)
  497.         return;
  498.     link = buddy_system_alloc_block(zone->buddy_system,
  499.                     &frame->buddy_link);
  500.     ASSERT(link);
  501.     zone->free_count--;
  502. }
  503.  
  504. /**
  505.  * Join 2 zones
  506.  *
  507.  * Expect zone_t *z to point to space at least zone_conf_size large
  508.  *
  509.  * Assume z1 & z2 are locked
  510.  */
  511.  
  512. static void _zone_merge(zone_t *z, zone_t *z1, zone_t *z2)
  513. {
  514.     __u8 max_order;
  515.     int i, z2idx;
  516.     pfn_t frame_idx;
  517.     frame_t *frame;
  518.  
  519.     ASSERT(!overlaps(z1->base,z1->count,z2->base,z2->count));
  520.     ASSERT(z1->base < z2->base);
  521.  
  522.     spinlock_initialize(&z->lock, "zone_lock");
  523.     z->base = z1->base;
  524.     z->count = z2->base+z2->count - z1->base;
  525.     z->flags = z1->flags & z2->flags;
  526.  
  527.     z->free_count = z1->free_count + z2->free_count;
  528.     z->busy_count = z1->busy_count + z2->busy_count;
  529.    
  530.     max_order = fnzb(z->count);
  531.  
  532.     z->buddy_system = (buddy_system_t *)&z[1];
  533.     buddy_system_create(z->buddy_system, max_order,
  534.                 &zone_buddy_system_operations,
  535.                 (void *) z);
  536.  
  537.     z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
  538.     for (i = 0; i < z->count; i++) {
  539.         /* This marks all frames busy */
  540.         frame_initialize(&z->frames[i]);
  541.     }
  542.     /* Copy frames from both zones to preserve full frame orders,
  543.      * parents etc. Set all frames with refcount=0 to 1, because
  544.      * we add all free frames to buddy allocator later again, clear
  545.      * order to 0.
  546.      */
  547.     for (i=0; i<z1->count; i++)
  548.         z->frames[i] = z1->frames[i];
  549.     for (i=0; i < z2->count; i++) {
  550.         z2idx = i + (z2->base - z1->base);
  551.         z->frames[z2idx] = z2->frames[i];
  552.     }
  553.     for (i=0; i < z->count; i++) {
  554.         if (!z->frames[i].refcount) {
  555.             z->frames[i].refcount = 1;
  556.             z->frames[i].buddy_order = 0;
  557.         }
  558.     }
  559.     /* Add free blocks from the 2 original zones */
  560.     while (zone_can_alloc(z1, 0)) {
  561.         frame_idx = zone_frame_alloc(z1, 0);
  562.         frame = &z->frames[frame_idx];
  563.         frame->refcount = 0;
  564.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  565.     }
  566.     while (zone_can_alloc(z2, 0)) {
  567.         frame_idx = zone_frame_alloc(z2, 0);
  568.         frame = &z->frames[frame_idx + (z2->base-z1->base)];
  569.         frame->refcount = 0;
  570.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  571.     }
  572. }
  573.  
  574. /** Return old configuration frames into the zone
  575.  *
  576.  * We have several cases
  577.  * - the conf. data is outside of zone -> exit, shall we call frame_free??
  578.  * - the conf. data was created by zone_create or
  579.  *   updated with reduce_region -> free every frame
  580.  *
  581.  * @param newzone The actual zone where freeing should occur
  582.  * @param oldzone Pointer to old zone configuration data that should
  583.  *                be freed from new zone
  584.  */
  585. static void return_config_frames(zone_t *newzone, zone_t *oldzone)
  586. {
  587.     pfn_t pfn;
  588.     frame_t *frame;
  589.     count_t cframes;
  590.     int i;
  591.  
  592.     pfn = ADDR2PFN((__address)KA2PA(oldzone));
  593.     cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
  594.    
  595.     if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
  596.         return;
  597.  
  598.     frame = &newzone->frames[pfn - newzone->base];
  599.     ASSERT(!frame->buddy_order);
  600.  
  601.     for (i=0; i < cframes; i++) {
  602.         newzone->busy_count++;
  603.         zone_frame_free(newzone, pfn+i-newzone->base);
  604.     }
  605. }
  606.  
  607.  
  608. /** Reduce allocated block to count of order 0 frames
  609.  *
  610.  * The allocated block need 2^order frames of space. Reduce all frames
  611.  * in block to order 0 and free the unneded frames. This means, that
  612.  * when freeing the block, you have to free every frame from block.
  613.  *
  614.  * @param zone
  615.  * @param frame_idx Index to block
  616.  * @param count Allocated space in block
  617.  */
  618. static void zone_reduce_region(zone_t *zone, pfn_t frame_idx, count_t count)
  619. {
  620.     count_t i;
  621.     __u8 order;
  622.     frame_t *frame;
  623.    
  624.     ASSERT(frame_idx+count < zone->count);
  625.  
  626.     order = zone->frames[frame_idx].buddy_order;
  627.     ASSERT((1 << order) >= count);
  628.  
  629.     /* Reduce all blocks to order 0 */
  630.     for (i=0; i < (1 << order); i++) {
  631.         frame = &zone->frames[i + frame_idx];
  632.         frame->buddy_order = 0;
  633.         if (! frame->refcount)
  634.             frame->refcount = 1;
  635.         ASSERT(frame->refcount == 1);
  636.     }
  637.     /* Free unneeded frames */
  638.     for (i=count; i < (1 << order); i++) {
  639.         zone_frame_free(zone, i + frame_idx);
  640.     }
  641. }
  642.  
  643. /** Merge zones z1 and z2
  644.  *
  645.  * - the zones must be 2 zones with no zone existing in between,
  646.  *   which means that z2 = z1+1
  647.  *
  648.  * - When you create a new zone, the frame allocator configuration does
  649.  *   not to be 2^order size. Once the allocator is running it is no longer
  650.  *   possible, merged configuration data occupies more space :-/
  651.  */
  652. void zone_merge(int z1, int z2)
  653. {
  654.     ipl_t ipl;
  655.     zone_t *zone1, *zone2, *newzone;
  656.     int cframes;
  657.     __u8 order;
  658.     int i;
  659.     pfn_t pfn;
  660.  
  661.     ipl = interrupts_disable();
  662.     spinlock_lock(&zones.lock);
  663.  
  664.     if (z1 < 0 || z1 >= zones.count || z2 < 0 || z2 >= zones.count)
  665.         goto errout;
  666.     /* We can join only 2 zones with none existing inbetween */
  667.     if (z2-z1 != 1)
  668.         goto errout;
  669.  
  670.     zone1 = zones.info[z1];
  671.     zone2 = zones.info[z2];
  672.     spinlock_lock(&zone1->lock);
  673.     spinlock_lock(&zone2->lock);
  674.  
  675.     cframes = SIZE2FRAMES(zone_conf_size(zone2->base+zone2->count-zone1->base));
  676.     order = fnzb(cframes) + 1;
  677.  
  678.     /* Allocate zonedata inside one of the zones */
  679.     if (zone_can_alloc(zone1, order))
  680.         pfn = zone1->base + zone_frame_alloc(zone1, order);
  681.     else if (zone_can_alloc(zone2, order))
  682.         pfn = zone2->base + zone_frame_alloc(zone2, order);
  683.     else
  684.         goto errout2;
  685.  
  686.     newzone = (zone_t *)PA2KA(PFN2ADDR(pfn));
  687.  
  688.     _zone_merge(newzone, zone1, zone2);
  689.  
  690.     /* Free unneeded config frames */
  691.     zone_reduce_region(newzone, pfn - newzone->base,  cframes);
  692.     /* Subtract zone information from busy frames */
  693.     newzone->busy_count -= cframes;
  694.  
  695.     /* Replace existing zones in zoneinfo list */
  696.     zones.info[z1] = newzone;
  697.     for (i=z2+1;i < zones.count;i++)
  698.         zones.info[i-1] = zones.info[i];
  699.     zones.count--;
  700.  
  701.     /* Free old zone information */
  702.     return_config_frames(newzone, zone1);
  703.     return_config_frames(newzone, zone2);
  704. errout2:
  705.     /* Nobody is allowed to enter to zone, so we are safe
  706.      * to touch the spinlocks last time */
  707.     spinlock_unlock(&zone1->lock);
  708.     spinlock_unlock(&zone2->lock);
  709. errout:
  710.     spinlock_unlock(&zones.lock);
  711.     interrupts_restore(ipl);
  712. }
  713.  
  714.  
  715. /**
  716.  * Merge all zones into one big zone
  717.  *
  718.  * It is reasonable to do this on systems whose bios reports parts in chunks,
  719.  * so that we could have 1 zone (it's faster).
  720.  */
  721. void zone_merge_all(void)
  722. {
  723.     int count = zones.count;
  724.  
  725.     while (zones.count > 1 && --count) {
  726.         zone_merge(0,1);
  727.         break;
  728.     }
  729. }
  730.  
  731. /** Create frame zone
  732.  *
  733.  * Create new frame zone.
  734.  *
  735.  * @param start Physical address of the first frame within the zone.
  736.  * @param size Size of the zone. Must be a multiple of FRAME_SIZE.
  737.  * @param conffram Address of configuration frame
  738.  * @param flags Zone flags.
  739.  *
  740.  * @return Initialized zone.
  741.  */
  742. static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
  743. {
  744.     int i;
  745.     __u8 max_order;
  746.  
  747.     spinlock_initialize(&z->lock, "zone_lock");
  748.     z->base = start;
  749.     z->count = count;
  750.     z->flags = flags;
  751.     z->free_count = count;
  752.     z->busy_count = 0;
  753.  
  754.     /*
  755.      * Compute order for buddy system, initialize
  756.      */
  757.     max_order = fnzb(count);
  758.     z->buddy_system = (buddy_system_t *)&z[1];
  759.    
  760.     buddy_system_create(z->buddy_system, max_order,
  761.                 &zone_buddy_system_operations,
  762.                 (void *) z);
  763.    
  764.     /* Allocate frames _after_ the conframe */
  765.     /* Check sizes */
  766.     z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
  767.     for (i = 0; i<count; i++) {
  768.         frame_initialize(&z->frames[i]);
  769.     }
  770.  
  771.     /* Stuffing frames */
  772.     for (i = 0; i < count; i++) {
  773.         z->frames[i].refcount = 0;
  774.         buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
  775.     }
  776. }
  777.  
  778.  
  779. /** Compute configuration data size for zone */
  780. __address zone_conf_size(count_t count)
  781. {
  782.     int size = sizeof(zone_t) + count*sizeof(frame_t);
  783.     int max_order;
  784.  
  785.     max_order = fnzb(count);
  786.     size += buddy_conf_size(max_order);
  787.     return size;
  788. }
  789.  
  790.  
  791. /** Create and add zone to system
  792.  *
  793.  * @param confframe Where configuration frame is supposed to be.
  794.  *                  Always check, that we will not disturb the kernel and possibly init.
  795.  *                  If confframe is given _outside_ this zone, it is expected,
  796.  *                  that the area is already marked BUSY and big enough
  797.  *                  to contain zone_conf_size() amount of data
  798.  *
  799.  * @return Zone number or -1 on error
  800.  */
  801. int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
  802. {
  803.     zone_t *z;
  804.     __address addr;
  805.     count_t confcount;
  806.     int i;
  807.     int znum;
  808.  
  809.     /* Theoretically we could have here 0, practically make sure
  810.      * nobody tries to do that. If some platform requires, remove
  811.      * the assert
  812.      */
  813.     ASSERT(confframe);
  814.     /* If conframe is supposed to be inside our zone, then make sure
  815.      * it does not span kernel & init
  816.      */
  817.     confcount = SIZE2FRAMES(zone_conf_size(count));
  818.     if (confframe >= start && confframe < start+count) {
  819.         for (;confframe < start+count;confframe++) {
  820.             addr = PFN2ADDR(confframe);
  821.             if (overlaps(addr, PFN2ADDR(confcount),
  822.                      KA2PA(config.base),config.kernel_size))
  823.                 continue;
  824.             if (config.init_addr)
  825.                 if (overlaps(addr,PFN2ADDR(confcount),
  826.                          KA2PA(config.init_addr),
  827.                          config.init_size))
  828.                     continue;
  829.             break;
  830.         }
  831.         if (confframe >= start+count)
  832.             panic("Cannot find configuration data for zone.");
  833.     }
  834.  
  835.     z = (zone_t *)PA2KA(PFN2ADDR(confframe));
  836.     zone_construct(start, count, z, flags);
  837.     znum = zones_add_zone(z);
  838.     if (znum == -1)
  839.         return -1;
  840.  
  841.     /* If confdata in zone, mark as unavailable */
  842.     if (confframe >= start && confframe < start+count)
  843.         for (i=confframe; i<confframe+confcount; i++) {
  844.             zone_mark_unavailable(z, i - z->base);
  845.         }
  846.  
  847.     return znum;
  848. }
  849.  
  850. /***************************************/
  851. /* Frame functions */
  852.  
  853. /** Set parent of frame */
  854. void frame_set_parent(pfn_t pfn, void *data, int hint)
  855. {
  856.     zone_t *zone = find_zone_and_lock(pfn, &hint);
  857.  
  858.     ASSERT(zone);
  859.  
  860.     zone_get_frame(zone, pfn-zone->base)->parent = data;
  861.     spinlock_unlock(&zone->lock);
  862. }
  863.  
  864. void * frame_get_parent(pfn_t pfn, int hint)
  865. {
  866.     zone_t *zone = find_zone_and_lock(pfn, &hint);
  867.     void *res;
  868.  
  869.     ASSERT(zone);
  870.     res = zone_get_frame(zone, pfn - zone->base)->parent;
  871.    
  872.     spinlock_unlock(&zone->lock);
  873.     return res;
  874. }
  875.  
  876. /** Allocate power-of-two frames of physical memory.
  877.  *
  878.  * @param flags Flags for host zone selection and address processing.
  879.  * @param order Allocate exactly 2^order frames.
  880.  * @param pzone Preferred zone
  881.  *
  882.  * @return Allocated frame.
  883.  */
  884. pfn_t frame_alloc_generic(__u8 order, int flags, int * status, int *pzone)
  885. {
  886.     ipl_t ipl;
  887.     int freed;
  888.     pfn_t v;
  889.     zone_t *zone;
  890.    
  891. loop:
  892.     ipl = interrupts_disable();
  893.     /*
  894.      * First, find suitable frame zone.
  895.      */
  896.     zone = find_free_zone_lock(order,pzone);
  897.     /* If no memory, reclaim some slab memory,
  898.        if it does not help, reclaim all */
  899.     if (!zone && !(flags & FRAME_NO_RECLAIM)) {
  900.         freed = slab_reclaim(0);
  901.         if (freed)
  902.             zone = find_free_zone_lock(order,pzone);
  903.         if (!zone) {
  904.             freed = slab_reclaim(SLAB_RECLAIM_ALL);
  905.             if (freed)
  906.                 zone = find_free_zone_lock(order,pzone);
  907.         }
  908.     }
  909.     if (!zone) {
  910.         if (flags & FRAME_PANIC)
  911.             panic("Can't allocate frame.\n");
  912.        
  913.         /*
  914.          * TODO: Sleep until frames are available again.
  915.          */
  916.         interrupts_restore(ipl);
  917.  
  918.         if (flags & FRAME_ATOMIC) {
  919.             ASSERT(status != NULL);
  920.             if (status)
  921.                 *status = FRAME_NO_MEMORY;
  922.             return NULL;
  923.         }
  924.        
  925.         panic("Sleep not implemented.\n");
  926.         goto loop;
  927.     }
  928.     v = zone_frame_alloc(zone,order);
  929.     v += zone->base;
  930.  
  931.     spinlock_unlock(&zone->lock);
  932.     interrupts_restore(ipl);
  933.  
  934.     if (status)
  935.         *status = FRAME_OK;
  936.     return v;
  937. }
  938.  
  939. /** Free a frame.
  940.  *
  941.  * Find respective frame structure for supplied addr.
  942.  * Decrement frame reference count.
  943.  * If it drops to zero, move the frame structure to free list.
  944.  *
  945.  * @param frame Frame no to be freed.
  946.  */
  947. void frame_free(pfn_t pfn)
  948. {
  949.     ipl_t ipl;
  950.     zone_t *zone;
  951.  
  952.     ipl = interrupts_disable();
  953.    
  954.     /*
  955.      * First, find host frame zone for addr.
  956.      */
  957.     zone = find_zone_and_lock(pfn,NULL);
  958.     ASSERT(zone);
  959.    
  960.     zone_frame_free(zone, pfn-zone->base);
  961.    
  962.     spinlock_unlock(&zone->lock);
  963.     interrupts_restore(ipl);
  964. }
  965.  
  966.  
  967.  
  968. /** Mark given range unavailable in frame zones */
  969. void frame_mark_unavailable(pfn_t start, count_t count)
  970. {
  971.     int i;
  972.     zone_t *zone;
  973.     int prefzone = 0;
  974.  
  975.     for (i=0; i < count; i++) {
  976.         zone = find_zone_and_lock(start+i,&prefzone);
  977.         if (!zone) /* PFN not found */
  978.             continue;
  979.         zone_mark_unavailable(zone, start+i-zone->base);
  980.  
  981.         spinlock_unlock(&zone->lock);
  982.     }
  983. }
  984.  
  985. /** Initialize physical memory management
  986.  *
  987.  * Initialize physical memory managemnt.
  988.  */
  989. void frame_init(void)
  990. {
  991.     if (config.cpu_active == 1) {
  992.         zones.count = 0;
  993.         spinlock_initialize(&zones.lock,"zones_glob_lock");
  994.     }
  995.     /* Tell the architecture to create some memory */
  996.     frame_arch_init();
  997.     if (config.cpu_active == 1) {
  998.         frame_mark_unavailable(ADDR2PFN(KA2PA(config.base)),
  999.                        SIZE2FRAMES(config.kernel_size));
  1000.         if (config.init_size > 0)
  1001.             frame_mark_unavailable(ADDR2PFN(KA2PA(config.init_addr)),
  1002.                            SIZE2FRAMES(config.init_size));
  1003.     }
  1004. }
  1005.  
  1006.  
  1007.  
  1008. /** Prints list of zones
  1009.  *
  1010.  */
  1011. void zone_print_list(void) {
  1012.     zone_t *zone = NULL;
  1013.     int i;
  1014.     ipl_t ipl;
  1015.  
  1016.     ipl = interrupts_disable();
  1017.     spinlock_lock(&zones.lock);
  1018.     printf("#  Base address\tFree Frames\tBusy Frames\n");
  1019.     printf("   ------------\t-----------\t-----------\n");
  1020.     for (i=0;i<zones.count;i++) {
  1021.         zone = zones.info[i];
  1022.         spinlock_lock(&zone->lock);
  1023.         printf("%d: %L\t%d\t\t%d\n",i,PFN2ADDR(zone->base),
  1024.                zone->free_count, zone->busy_count);
  1025.         spinlock_unlock(&zone->lock);
  1026.     }
  1027.     spinlock_unlock(&zones.lock);
  1028.     interrupts_restore(ipl);
  1029. }
  1030.  
  1031. /** Prints zone details
  1032.  *
  1033.  * @param base Zone base address OR zone number
  1034.  */
  1035. void zone_print_one(int num) {
  1036.     zone_t *zone = NULL;
  1037.     ipl_t ipl;
  1038.     int i;
  1039.  
  1040.     ipl = interrupts_disable();
  1041.     spinlock_lock(&zones.lock);
  1042.  
  1043.     for (i=0;i < zones.count; i++) {
  1044.         if (i == num || PFN2ADDR(zones.info[i]->base) == num) {
  1045.             zone = zones.info[i];
  1046.             break;
  1047.         }
  1048.     }
  1049.     if (!zone) {
  1050.         printf("Zone not found.\n");
  1051.         goto out;
  1052.     }
  1053.    
  1054.     spinlock_lock(&zone->lock);
  1055.     printf("Memory zone information\n");
  1056.     printf("Zone base address: %P\n", PFN2ADDR(zone->base));
  1057.     printf("Zone size: %d frames (%dK)\n", zone->count, ((zone->count) * FRAME_SIZE) >> 10);
  1058.     printf("Allocated space: %d frames (%dK)\n", zone->busy_count, (zone->busy_count * FRAME_SIZE) >> 10);
  1059.     printf("Available space: %d (%dK)\n", zone->free_count, (zone->free_count * FRAME_SIZE) >> 10);
  1060.     buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
  1061.    
  1062.     spinlock_unlock(&zone->lock);
  1063. out:
  1064.     spinlock_unlock(&zones.lock);
  1065.     interrupts_restore(ipl);
  1066. }
  1067.  
  1068.