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