Subversion Repositories HelenOS-historic

Rev

Rev 946 | Rev 1093 | 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. /*
  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.     if (frame_index_valid(zone, index)) {
  314.         if (zone->frames[index].buddy_order == frame->buddy_order &&
  315.             zone->frames[index].refcount == 0) {
  316.             return &zone->frames[index].buddy_link;
  317.         }
  318.     }
  319.  
  320.     return NULL;   
  321. }
  322.  
  323. /** Buddy system bisect implementation
  324.  *
  325.  * @param b Buddy system.
  326.  * @param block Block to bisect
  327.  *
  328.  * @return right block
  329.  */
  330. static link_t * zone_buddy_bisect(buddy_system_t *b, link_t * block) {
  331.     frame_t * frame_l, * frame_r;
  332.  
  333.     frame_l = list_get_instance(block, frame_t, buddy_link);
  334.     frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
  335.    
  336.     return &frame_r->buddy_link;
  337. }
  338.  
  339. /** Buddy system coalesce implementation
  340.  *
  341.  * @param b Buddy system.
  342.  * @param block_1 First block
  343.  * @param block_2 First block's buddy
  344.  *
  345.  * @return Coalesced block (actually block that represents lower address)
  346.  */
  347. static link_t * zone_buddy_coalesce(buddy_system_t *b, link_t * block_1,
  348.                     link_t * block_2)
  349. {
  350.     frame_t *frame1, *frame2;
  351.    
  352.     frame1 = list_get_instance(block_1, frame_t, buddy_link);
  353.     frame2 = list_get_instance(block_2, frame_t, buddy_link);
  354.    
  355.     return frame1 < frame2 ? block_1 : block_2;
  356. }
  357.  
  358. /** Buddy system set_order implementation
  359.  *
  360.  * @param b Buddy system.
  361.  * @param block Buddy system block
  362.  * @param order Order to set
  363.  */
  364. static void zone_buddy_set_order(buddy_system_t *b, link_t * block, __u8 order) {
  365.     frame_t * frame;
  366.     frame = list_get_instance(block, frame_t, buddy_link);
  367.     frame->buddy_order = order;
  368. }
  369.  
  370. /** Buddy system get_order implementation
  371.  *
  372.  * @param b Buddy system.
  373.  * @param block Buddy system block
  374.  *
  375.  * @return Order of block
  376.  */
  377. static __u8 zone_buddy_get_order(buddy_system_t *b, link_t * block) {
  378.     frame_t * frame;
  379.     frame = list_get_instance(block, frame_t, buddy_link);
  380.     return frame->buddy_order;
  381. }
  382.  
  383. /** Buddy system mark_busy implementation
  384.  *
  385.  * @param b Buddy system
  386.  * @param block Buddy system block
  387.  *
  388.  */
  389. static void zone_buddy_mark_busy(buddy_system_t *b, link_t * block) {
  390.     frame_t * frame;
  391.  
  392.     frame = list_get_instance(block, frame_t, buddy_link);
  393.     frame->refcount = 1;
  394. }
  395.  
  396. /** Buddy system mark_available implementation
  397.  *
  398.  * @param b Buddy system
  399.  * @param block Buddy system block
  400.  *
  401.  */
  402. static void zone_buddy_mark_available(buddy_system_t *b, link_t * block) {
  403.     frame_t * frame;
  404.     frame = list_get_instance(block, frame_t, buddy_link);
  405.     frame->refcount = 0;
  406. }
  407.  
  408. static struct buddy_system_operations  zone_buddy_system_operations = {
  409.     .find_buddy = zone_buddy_find_buddy,
  410.     .bisect = zone_buddy_bisect,
  411.     .coalesce = zone_buddy_coalesce,
  412.     .set_order = zone_buddy_set_order,
  413.     .get_order = zone_buddy_get_order,
  414.     .mark_busy = zone_buddy_mark_busy,
  415.     .mark_available = zone_buddy_mark_available,
  416.     .find_block = zone_buddy_find_block,
  417.     .print_id = zone_buddy_print_id
  418. };
  419.  
  420. /*************************************/
  421. /* Zone functions */
  422.  
  423. /** Allocate frame in particular zone
  424.  *
  425.  * Assume zone is locked
  426.  * Panics, if allocation is impossible.
  427.  *
  428.  * @return Frame index in zone
  429.  */
  430. static pfn_t zone_frame_alloc(zone_t *zone,__u8 order)
  431. {
  432.     pfn_t v;
  433.     link_t *tmp;
  434.     frame_t *frame;
  435.  
  436.     /* Allocate frames from zone buddy system */
  437.     tmp = buddy_system_alloc(zone->buddy_system, order);
  438.    
  439.     ASSERT(tmp);
  440.    
  441.     /* Update zone information. */
  442.     zone->free_count -= (1 << order);
  443.     zone->busy_count += (1 << order);
  444.  
  445.     /* Frame will be actually a first frame of the block. */
  446.     frame = list_get_instance(tmp, frame_t, buddy_link);
  447.    
  448.     /* get frame address */
  449.     v = make_frame_index(zone, frame);
  450.     return v;
  451. }
  452.  
  453. /** Free frame from zone
  454.  *
  455.  * Assume zone is locked
  456.  */
  457. static void zone_frame_free(zone_t *zone, index_t frame_idx)
  458. {
  459.     frame_t *frame;
  460.     __u8 order;
  461.  
  462.     frame = &zone->frames[frame_idx];
  463.    
  464.     /* remember frame order */
  465.     order = frame->buddy_order;
  466.  
  467.     ASSERT(frame->refcount);
  468.  
  469.     if (!--frame->refcount) {
  470.         buddy_system_free(zone->buddy_system, &frame->buddy_link);
  471.    
  472.         /* Update zone information. */
  473.         zone->free_count += (1 << order);
  474.         zone->busy_count -= (1 << order);
  475.     }
  476. }
  477.  
  478. /** Return frame from zone */
  479. static frame_t * zone_get_frame(zone_t *zone, index_t frame_idx)
  480. {
  481.     ASSERT(frame_idx < zone->count);
  482.     return &zone->frames[frame_idx];
  483. }
  484.  
  485. /** Mark frame in zone unavailable to allocation */
  486. static void zone_mark_unavailable(zone_t *zone, index_t frame_idx)
  487. {
  488.     frame_t *frame;
  489.     link_t *link;
  490.  
  491.     frame = zone_get_frame(zone, frame_idx);
  492.     if (frame->refcount)
  493.         return;
  494.     link = buddy_system_alloc_block(zone->buddy_system,
  495.                     &frame->buddy_link);
  496.     ASSERT(link);
  497.     zone->free_count--;
  498. }
  499.  
  500. /**
  501.  * Join 2 zones
  502.  *
  503.  * Expect zone_t *z to point to space at least zone_conf_size large
  504.  *
  505.  * Assume z1 & z2 are locked
  506.  */
  507.  
  508. static void _zone_merge(zone_t *z, zone_t *z1, zone_t *z2)
  509. {
  510.     __u8 max_order;
  511.     int i, z2idx;
  512.     pfn_t frame_idx;
  513.     frame_t *frame;
  514.  
  515.     ASSERT(!overlaps(z1->base,z1->count,z2->base,z2->count));
  516.     ASSERT(z1->base < z2->base);
  517.  
  518.     spinlock_initialize(&z->lock, "zone_lock");
  519.     z->base = z1->base;
  520.     z->count = z2->base+z2->count - z1->base;
  521.     z->flags = z1->flags & z2->flags;
  522.  
  523.     z->free_count = z1->free_count + z2->free_count;
  524.     z->busy_count = z1->busy_count + z2->busy_count;
  525.    
  526.     max_order = fnzb(z->count);
  527.  
  528.     z->buddy_system = (buddy_system_t *)&z[1];
  529.     buddy_system_create(z->buddy_system, max_order,
  530.                 &zone_buddy_system_operations,
  531.                 (void *) z);
  532.  
  533.     z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
  534.     for (i = 0; i < z->count; i++) {
  535.         /* This marks all frames busy */
  536.         frame_initialize(&z->frames[i]);
  537.     }
  538.     /* Copy frames from both zones to preserve full frame orders,
  539.      * parents etc. Set all frames with refcount=0 to 1, because
  540.      * we add all free frames to buddy allocator later again, clear
  541.      * order to 0.
  542.      */
  543.     for (i=0; i<z1->count; i++)
  544.         z->frames[i] = z1->frames[i];
  545.     for (i=0; i < z2->count; i++) {
  546.         z2idx = i + (z2->base - z1->base);
  547.         z->frames[z2idx] = z2->frames[i];
  548.     }
  549.     for (i=0; i < z->count; i++) {
  550.         if (!z->frames[i].refcount) {
  551.             z->frames[i].refcount = 1;
  552.             z->frames[i].buddy_order = 0;
  553.         }
  554.     }
  555.     /* Add free blocks from the 2 original zones */
  556.     while (zone_can_alloc(z1, 0)) {
  557.         frame_idx = zone_frame_alloc(z1, 0);
  558.         frame = &z->frames[frame_idx];
  559.         frame->refcount = 0;
  560.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  561.     }
  562.     while (zone_can_alloc(z2, 0)) {
  563.         frame_idx = zone_frame_alloc(z2, 0);
  564.         frame = &z->frames[frame_idx + (z2->base-z1->base)];
  565.         frame->refcount = 0;
  566.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  567.     }
  568. }
  569.  
  570. /** Return old configuration frames into the zone
  571.  *
  572.  * We have several cases
  573.  * - the conf. data is outside of zone -> exit, shall we call frame_free??
  574.  * - the conf. data was created by zone_create or
  575.  *   updated with reduce_region -> free every frame
  576.  *
  577.  * @param newzone The actual zone where freeing should occur
  578.  * @param oldzone Pointer to old zone configuration data that should
  579.  *                be freed from new zone
  580.  */
  581. static void return_config_frames(zone_t *newzone, zone_t *oldzone)
  582. {
  583.     pfn_t pfn;
  584.     frame_t *frame;
  585.     count_t cframes;
  586.     int i;
  587.  
  588.     pfn = ADDR2PFN((__address)KA2PA(oldzone));
  589.     cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
  590.    
  591.     if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
  592.         return;
  593.  
  594.     frame = &newzone->frames[pfn - newzone->base];
  595.     ASSERT(!frame->buddy_order);
  596.  
  597.     for (i=0; i < cframes; i++) {
  598.         newzone->busy_count++;
  599.         zone_frame_free(newzone, pfn+i-newzone->base);
  600.     }
  601. }
  602.  
  603. /** Reduce allocated block to count of order 0 frames
  604.  *
  605.  * The allocated block need 2^order frames of space. Reduce all frames
  606.  * in block to order 0 and free the unneded frames. This means, that
  607.  * when freeing the block, you have to free every frame from block.
  608.  *
  609.  * @param zone
  610.  * @param frame_idx Index to block
  611.  * @param count Allocated space in block
  612.  */
  613. static void zone_reduce_region(zone_t *zone, pfn_t frame_idx, count_t count)
  614. {
  615.     count_t i;
  616.     __u8 order;
  617.     frame_t *frame;
  618.    
  619.     ASSERT(frame_idx+count < zone->count);
  620.  
  621.     order = zone->frames[frame_idx].buddy_order;
  622.     ASSERT((1 << order) >= count);
  623.  
  624.     /* Reduce all blocks to order 0 */
  625.     for (i=0; i < (1 << order); i++) {
  626.         frame = &zone->frames[i + frame_idx];
  627.         frame->buddy_order = 0;
  628.         if (! frame->refcount)
  629.             frame->refcount = 1;
  630.         ASSERT(frame->refcount == 1);
  631.     }
  632.     /* Free unneeded frames */
  633.     for (i=count; i < (1 << order); i++) {
  634.         zone_frame_free(zone, i + frame_idx);
  635.     }
  636. }
  637.  
  638. /** Merge zones z1 and z2
  639.  *
  640.  * - the zones must be 2 zones with no zone existing in between,
  641.  *   which means that z2 = z1+1
  642.  *
  643.  * - When you create a new zone, the frame allocator configuration does
  644.  *   not to be 2^order size. Once the allocator is running it is no longer
  645.  *   possible, merged configuration data occupies more space :-/
  646.  */
  647. void zone_merge(int z1, int z2)
  648. {
  649.     ipl_t ipl;
  650.     zone_t *zone1, *zone2, *newzone;
  651.     int cframes;
  652.     __u8 order;
  653.     int i;
  654.     pfn_t pfn;
  655.  
  656.     ipl = interrupts_disable();
  657.     spinlock_lock(&zones.lock);
  658.  
  659.     if (z1 < 0 || z1 >= zones.count || z2 < 0 || z2 >= zones.count)
  660.         goto errout;
  661.     /* We can join only 2 zones with none existing inbetween */
  662.     if (z2-z1 != 1)
  663.         goto errout;
  664.  
  665.     zone1 = zones.info[z1];
  666.     zone2 = zones.info[z2];
  667.     spinlock_lock(&zone1->lock);
  668.     spinlock_lock(&zone2->lock);
  669.  
  670.     cframes = SIZE2FRAMES(zone_conf_size(zone2->base+zone2->count-zone1->base));
  671.     order = fnzb(cframes) + 1;
  672.  
  673.     /* Allocate zonedata inside one of the zones */
  674.     if (zone_can_alloc(zone1, order))
  675.         pfn = zone1->base + zone_frame_alloc(zone1, order);
  676.     else if (zone_can_alloc(zone2, order))
  677.         pfn = zone2->base + zone_frame_alloc(zone2, order);
  678.     else
  679.         goto errout2;
  680.  
  681.     newzone = (zone_t *)PA2KA(PFN2ADDR(pfn));
  682.  
  683.     _zone_merge(newzone, zone1, zone2);
  684.  
  685.     /* Free unneeded config frames */
  686.     zone_reduce_region(newzone, pfn - newzone->base,  cframes);
  687.     /* Subtract zone information from busy frames */
  688.     newzone->busy_count -= cframes;
  689.  
  690.     /* Replace existing zones in zoneinfo list */
  691.     zones.info[z1] = newzone;
  692.     for (i = z2 + 1; i < zones.count; i++)
  693.         zones.info[i - 1] = zones.info[i];
  694.     zones.count--;
  695.  
  696.     /* Free old zone information */
  697.     return_config_frames(newzone, zone1);
  698.     return_config_frames(newzone, zone2);
  699. errout2:
  700.     /* Nobody is allowed to enter to zone, so we are safe
  701.      * to touch the spinlocks last time */
  702.     spinlock_unlock(&zone1->lock);
  703.     spinlock_unlock(&zone2->lock);
  704. errout:
  705.     spinlock_unlock(&zones.lock);
  706.     interrupts_restore(ipl);
  707. }
  708.  
  709. /**
  710.  * Merge all zones into one big zone
  711.  *
  712.  * It is reasonable to do this on systems whose bios reports parts in chunks,
  713.  * so that we could have 1 zone (it's faster).
  714.  */
  715. void zone_merge_all(void)
  716. {
  717.     int count = zones.count;
  718.  
  719.     while (zones.count > 1 && --count) {
  720.         zone_merge(0,1);
  721.         break;
  722.     }
  723. }
  724.  
  725. /** Create frame zone
  726.  *
  727.  * Create new frame zone.
  728.  *
  729.  * @param start Physical address of the first frame within the zone.
  730.  * @param size Size of the zone. Must be a multiple of FRAME_SIZE.
  731.  * @param conffram Address of configuration frame
  732.  * @param flags Zone flags.
  733.  *
  734.  * @return Initialized zone.
  735.  */
  736. static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
  737. {
  738.     int i;
  739.     __u8 max_order;
  740.  
  741.     spinlock_initialize(&z->lock, "zone_lock");
  742.     z->base = start;
  743.     z->count = count;
  744.     z->flags = flags;
  745.     z->free_count = count;
  746.     z->busy_count = 0;
  747.  
  748.     /*
  749.      * Compute order for buddy system, initialize
  750.      */
  751.     max_order = fnzb(count);
  752.     z->buddy_system = (buddy_system_t *)&z[1];
  753.    
  754.     buddy_system_create(z->buddy_system, max_order,
  755.                 &zone_buddy_system_operations,
  756.                 (void *) z);
  757.    
  758.     /* Allocate frames _after_ the conframe */
  759.     /* Check sizes */
  760.     z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
  761.     for (i = 0; i<count; i++) {
  762.         frame_initialize(&z->frames[i]);
  763.     }
  764.    
  765.     /* Stuffing frames */
  766.     for (i = 0; i < count; i++) {
  767.         z->frames[i].refcount = 0;
  768.         buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
  769.     }
  770. }
  771.  
  772. /** Compute configuration data size for zone */
  773. __address zone_conf_size(count_t count)
  774. {
  775.     int size = sizeof(zone_t) + count*sizeof(frame_t);
  776.     int max_order;
  777.  
  778.     max_order = fnzb(count);
  779.     size += buddy_conf_size(max_order);
  780.     return size;
  781. }
  782.  
  783. /** Create and add zone to system
  784.  *
  785.  * @param confframe Where configuration frame is supposed to be.
  786.  *                  Always check, that we will not disturb the kernel and possibly init.
  787.  *                  If confframe is given _outside_ this zone, it is expected,
  788.  *                  that the area is already marked BUSY and big enough
  789.  *                  to contain zone_conf_size() amount of data
  790.  *
  791.  * @return Zone number or -1 on error
  792.  */
  793. int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
  794. {
  795.     zone_t *z;
  796.     __address addr;
  797.     count_t confcount;
  798.     int i;
  799.     int znum;
  800.  
  801.     /* Theoretically we could have here 0, practically make sure
  802.      * nobody tries to do that. If some platform requires, remove
  803.      * the assert
  804.      */
  805.     ASSERT(confframe);
  806.     /* If conframe is supposed to be inside our zone, then make sure
  807.      * it does not span kernel & init
  808.      */
  809.     confcount = SIZE2FRAMES(zone_conf_size(count));
  810.     if (confframe >= start && confframe < start+count) {
  811.         for (;confframe < start + count; confframe++) {
  812.             addr = PFN2ADDR(confframe);
  813.             if (overlaps(addr, PFN2ADDR(confcount), KA2PA(config.base), config.kernel_size))
  814.                 continue;
  815.            
  816.             bool overlap = false;
  817.             count_t i;
  818.             for (i = 0; i < init.cnt; i++)
  819.                 if (overlaps(addr, PFN2ADDR(confcount), KA2PA(init.tasks[i].addr), init.tasks[i].size)) {
  820.                     overlap = true;
  821.                     break;
  822.                 }
  823.             if (overlap)
  824.                 continue;
  825.            
  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.        
  998.         count_t i;
  999.         for (i = 0; i < init.cnt; i++)
  1000.             frame_mark_unavailable(ADDR2PFN(KA2PA(init.tasks[i].addr)), SIZE2FRAMES(init.tasks[i].size));
  1001.     }
  1002. }
  1003.  
  1004.  
  1005.  
  1006. /** Prints list of zones
  1007.  *
  1008.  */
  1009. void zone_print_list(void) {
  1010.     zone_t *zone = NULL;
  1011.     int i;
  1012.     ipl_t ipl;
  1013.  
  1014.     ipl = interrupts_disable();
  1015.     spinlock_lock(&zones.lock);
  1016.     printf("#  Base address\tFree Frames\tBusy Frames\n");
  1017.     printf("   ------------\t-----------\t-----------\n");
  1018.     for (i = 0; i < zones.count; i++) {
  1019.         zone = zones.info[i];
  1020.         spinlock_lock(&zone->lock);
  1021.         printf("%d: %L\t%d\t\t%d\n",i,PFN2ADDR(zone->base),
  1022.                zone->free_count, zone->busy_count);
  1023.         spinlock_unlock(&zone->lock);
  1024.     }
  1025.     spinlock_unlock(&zones.lock);
  1026.     interrupts_restore(ipl);
  1027. }
  1028.  
  1029. /** Prints zone details
  1030.  *
  1031.  * @param base Zone base address OR zone number
  1032.  */
  1033. void zone_print_one(int num) {
  1034.     zone_t *zone = NULL;
  1035.     ipl_t ipl;
  1036.     int i;
  1037.  
  1038.     ipl = interrupts_disable();
  1039.     spinlock_lock(&zones.lock);
  1040.  
  1041.     for (i = 0; i < zones.count; i++) {
  1042.         if (i == num || PFN2ADDR(zones.info[i]->base) == num) {
  1043.             zone = zones.info[i];
  1044.             break;
  1045.         }
  1046.     }
  1047.     if (!zone) {
  1048.         printf("Zone not found.\n");
  1049.         goto out;
  1050.     }
  1051.    
  1052.     spinlock_lock(&zone->lock);
  1053.     printf("Memory zone information\n");
  1054.     printf("Zone base address: %P\n", PFN2ADDR(zone->base));
  1055.     printf("Zone size: %d frames (%dK)\n", zone->count, ((zone->count) * FRAME_SIZE) >> 10);
  1056.     printf("Allocated space: %d frames (%dK)\n", zone->busy_count, (zone->busy_count * FRAME_SIZE) >> 10);
  1057.     printf("Available space: %d (%dK)\n", zone->free_count, (zone->free_count * FRAME_SIZE) >> 10);
  1058.     buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
  1059.    
  1060.     spinlock_unlock(&zone->lock);
  1061. out:
  1062.     spinlock_unlock(&zones.lock);
  1063.     interrupts_restore(ipl);
  1064. }
  1065.  
  1066.