Subversion Repositories HelenOS-historic

Rev

Rev 1221 | Rev 1236 | 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. #include <macros.h>
  55.  
  56. typedef struct {
  57.     count_t refcount;   /**< tracking of shared frames  */
  58.     __u8 buddy_order;   /**< buddy system block order */
  59.     link_t buddy_link;  /**< link to the next free block inside one order */
  60.     void *parent;           /**< If allocated by slab, this points there */
  61. }frame_t;
  62.  
  63. typedef struct {
  64.     SPINLOCK_DECLARE(lock); /**< this lock protects everything below */
  65.     pfn_t base; /**< frame_no of the first frame in the frames array */
  66.     count_t count;          /**< Size of zone */
  67.  
  68.     frame_t *frames;    /**< array of frame_t structures in this zone */
  69.     count_t free_count; /**< number of free frame_t structures */
  70.     count_t busy_count; /**< number of busy frame_t structures */
  71.    
  72.     buddy_system_t * buddy_system; /**< buddy system for the zone */
  73.     int flags;
  74. }zone_t;
  75.  
  76. /*
  77.  * The zoneinfo.lock must be locked when accessing zoneinfo structure.
  78.  * Some of the attributes in zone_t structures are 'read-only'
  79.  */
  80.  
  81. struct {
  82.     SPINLOCK_DECLARE(lock);
  83.     int count;
  84.     zone_t *info[ZONES_MAX];
  85. }zones;
  86.  
  87.  
  88. /*********************************/
  89. /* Helper functions */
  90. static inline index_t frame_index(zone_t *zone, frame_t *frame)
  91. {
  92.     return (index_t)(frame - zone->frames);
  93. }
  94. static inline index_t frame_index_abs(zone_t *zone, frame_t *frame)
  95. {
  96.     return (index_t)(frame - zone->frames) + zone->base;
  97. }
  98. static inline int frame_index_valid(zone_t *zone, index_t index)
  99. {
  100.     return index >= 0 && index < zone->count;
  101. }
  102.  
  103. /** Compute pfn_t from frame_t pointer & zone pointer */
  104. static index_t make_frame_index(zone_t *zone, frame_t *frame)
  105. {
  106.     return frame - zone->frames;
  107. }
  108.  
  109. /** Initialize frame structure
  110.  *
  111.  * Initialize frame structure.
  112.  *
  113.  * @param frame Frame structure to be initialized.
  114.  */
  115. static void frame_initialize(frame_t *frame)
  116. {
  117.     frame->refcount = 1;
  118.     frame->buddy_order = 0;
  119. }
  120.  
  121. /*************************************/
  122. /* Zoneinfo functions */
  123.  
  124. /**
  125.  * Insert-sort zone into zones list
  126.  *
  127.  * @return zone number on success, -1 on error
  128.  */
  129. static int zones_add_zone(zone_t *newzone)
  130. {
  131.     int i,j;
  132.     ipl_t ipl;
  133.     zone_t *z;
  134.  
  135.     ipl = interrupts_disable();
  136.     spinlock_lock(&zones.lock);
  137.     /* Try to merge */
  138.     if (zones.count + 1 == ZONES_MAX)
  139.         panic("Maximum zone(%d) count exceeded.", ZONES_MAX);
  140.     for (i = 0; i < zones.count; i++) {
  141.         /* Check for overflow */
  142.         z = zones.info[i];
  143.         if (overlaps(newzone->base,newzone->count,
  144.                  z->base, z->count)) {
  145.             printf("Zones overlap!\n");
  146.             return -1;
  147.         }
  148.         if (newzone->base < z->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.     zones.info[i] = newzone;
  155.     zones.count++;
  156.     spinlock_unlock(&zones.lock);
  157.     interrupts_restore(ipl);
  158.  
  159.     return i;
  160. }
  161.  
  162. /**
  163.  * Try to find a zone where can we find the frame
  164.  *
  165.  * @param hint Start searching in zone 'hint'
  166.  * @param lock Lock zone if true
  167.  *
  168.  * Assume interrupts disable
  169.  */
  170. static zone_t * find_zone_and_lock(pfn_t frame, int *pzone)
  171. {
  172.     int i;
  173.     int hint = pzone ? *pzone : 0;
  174.     zone_t *z;
  175.    
  176.     spinlock_lock(&zones.lock);
  177.  
  178.     if (hint >= zones.count || hint < 0)
  179.         hint = 0;
  180.    
  181.     i = hint;
  182.     do {
  183.         z = zones.info[i];
  184.         spinlock_lock(&z->lock);
  185.         if (z->base <= frame && z->base + z->count > frame) {
  186.             spinlock_unlock(&zones.lock); /* Unlock the global lock */
  187.             if (pzone)
  188.                 *pzone = i;
  189.             return z;
  190.         }
  191.         spinlock_unlock(&z->lock);
  192.  
  193.         i++;
  194.         if (i >= zones.count)
  195.             i = 0;
  196.     } while(i != hint);
  197.  
  198.     spinlock_unlock(&zones.lock);
  199.     return NULL;
  200. }
  201.  
  202. /** @return True if zone can allocate specified order */
  203. static int zone_can_alloc(zone_t *z, __u8 order)
  204. {
  205.     return buddy_system_can_alloc(z->buddy_system, order);
  206. }
  207.  
  208. /**
  209.  * Find AND LOCK zone that can allocate order frames
  210.  *
  211.  * Assume interrupts are disabled!!
  212.  *
  213.  * @param pzone Pointer to preferred zone or NULL, on return contains zone number
  214.  */
  215. static zone_t * find_free_zone_lock(__u8 order, int *pzone)
  216. {
  217.     int i;
  218.     zone_t *z;
  219.     int hint = pzone ? *pzone : 0;
  220.    
  221.     spinlock_lock(&zones.lock);
  222.     if (hint >= zones.count)
  223.         hint = 0;
  224.     i = hint;
  225.     do {
  226.         z = zones.info[i];
  227.        
  228.         spinlock_lock(&z->lock);
  229.  
  230.         /* Check if the zone has 2^order frames area available  */
  231.         if (zone_can_alloc(z, order)) {
  232.             spinlock_unlock(&zones.lock);
  233.             if (pzone)
  234.                 *pzone = i;
  235.             return z;
  236.         }
  237.         spinlock_unlock(&z->lock);
  238.         if (++i >= zones.count)
  239.             i = 0;
  240.     } while(i != hint);
  241.     spinlock_unlock(&zones.lock);
  242.     return NULL;
  243. }
  244.  
  245. /********************************************/
  246. /* Buddy system functions */
  247.  
  248. /** Buddy system find_block implementation
  249.  *
  250.  * Find block that is parent of current list.
  251.  * That means go to lower addresses, until such block is found
  252.  *
  253.  * @param order - Order of parent must be different then this parameter!!
  254.  */
  255. static link_t *zone_buddy_find_block(buddy_system_t *b, link_t *child,
  256.                      __u8 order)
  257. {
  258.     frame_t * frame;
  259.     zone_t * zone;
  260.     index_t index;
  261.    
  262.     frame = list_get_instance(child, frame_t, buddy_link);
  263.     zone = (zone_t *) b->data;
  264.  
  265.     index = frame_index(zone, frame);
  266.     do {
  267.         if (zone->frames[index].buddy_order != order) {
  268.             return &zone->frames[index].buddy_link;
  269.         }
  270.     } while(index-- > 0);
  271.     return NULL;
  272. }
  273.  
  274. static void zone_buddy_print_id(buddy_system_t *b, link_t *block)
  275. {
  276.     frame_t * frame;
  277.     zone_t * zone;
  278.     index_t index;
  279.  
  280.     frame = list_get_instance(block, frame_t, buddy_link);
  281.     zone = (zone_t *) b->data;
  282.     index = frame_index(zone, frame);
  283.     printf("%zd", index);
  284. }                    
  285.  
  286. /** Buddy system find_buddy implementation
  287.  *
  288.  * @param b Buddy system.
  289.  * @param block Block for which buddy should be found
  290.  *
  291.  * @return Buddy for given block if found
  292.  */
  293. static link_t * zone_buddy_find_buddy(buddy_system_t *b, link_t * block)
  294. {
  295.     frame_t * frame;
  296.     zone_t * zone;
  297.     index_t index;
  298.     bool is_left, is_right;
  299.  
  300.     frame = list_get_instance(block, frame_t, buddy_link);
  301.     zone = (zone_t *) b->data;
  302.     ASSERT(IS_BUDDY_ORDER_OK(frame_index_abs(zone, frame), frame->buddy_order));
  303.    
  304.     is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
  305.     is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
  306.  
  307.     ASSERT(is_left ^ is_right);
  308.     if (is_left) {
  309.         index = (frame_index(zone, frame)) + (1 << frame->buddy_order);
  310.     } else { // if (is_right)
  311.         index = (frame_index(zone, frame)) - (1 << frame->buddy_order);
  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.         /* Update zone information. */
  474.         zone->free_count += (1 << order);
  475.         zone->busy_count -= (1 << order);
  476.     }
  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 free frames with refcount=0 to 1, because
  541.      * we add all free frames to buddy allocator later again, clear
  542.      * order to 0. Don't set busy frames with refcount=0, as they
  543.      * will not be reallocated during merge and it would make later
  544.      * problems with allocation/free.
  545.      */
  546.     for (i=0; i<z1->count; i++)
  547.         z->frames[i] = z1->frames[i];
  548.     for (i=0; i < z2->count; i++) {
  549.         z2idx = i + (z2->base - z1->base);
  550.         z->frames[z2idx] = z2->frames[i];
  551.     }
  552.     i = 0;
  553.     while (i < z->count) {
  554.         if (z->frames[i].refcount) {
  555.             /* skip busy frames */
  556.             i += 1 << z->frames[i].buddy_order;
  557.         } else { /* Free frames, set refcount=1 */
  558.             /* All free frames have refcount=0, we need not
  559.              * to check the order */
  560.             z->frames[i].refcount = 1;
  561.             z->frames[i].buddy_order = 0;
  562.             i++;
  563.         }
  564.     }
  565.     /* Add free blocks from the 2 original zones */
  566.     while (zone_can_alloc(z1, 0)) {
  567.         frame_idx = zone_frame_alloc(z1, 0);
  568.         frame = &z->frames[frame_idx];
  569.         frame->refcount = 0;
  570.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  571.     }
  572.     while (zone_can_alloc(z2, 0)) {
  573.         frame_idx = zone_frame_alloc(z2, 0);
  574.         frame = &z->frames[frame_idx + (z2->base-z1->base)];
  575.         frame->refcount = 0;
  576.         buddy_system_free(z->buddy_system, &frame->buddy_link);
  577.     }
  578. }
  579.  
  580. /** Return old configuration frames into the zone
  581.  *
  582.  * We have several cases
  583.  * - the conf. data is outside of zone -> exit, shall we call frame_free??
  584.  * - the conf. data was created by zone_create or
  585.  *   updated with reduce_region -> free every frame
  586.  *
  587.  * @param newzone The actual zone where freeing should occur
  588.  * @param oldzone Pointer to old zone configuration data that should
  589.  *                be freed from new zone
  590.  */
  591. static void return_config_frames(zone_t *newzone, zone_t *oldzone)
  592. {
  593.     pfn_t pfn;
  594.     frame_t *frame;
  595.     count_t cframes;
  596.     int i;
  597.  
  598.     pfn = ADDR2PFN((__address)KA2PA(oldzone));
  599.     cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
  600.    
  601.     if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
  602.         return;
  603.  
  604.     frame = &newzone->frames[pfn - newzone->base];
  605.     ASSERT(!frame->buddy_order);
  606.  
  607.     for (i=0; i < cframes; i++) {
  608.         newzone->busy_count++;
  609.         zone_frame_free(newzone, pfn+i-newzone->base);
  610.     }
  611. }
  612.  
  613. /** Reduce allocated block to count of order 0 frames
  614.  *
  615.  * The allocated block need 2^order frames of space. Reduce all frames
  616.  * in block to order 0 and free the unneded frames. This means, that
  617.  * when freeing the block, you have to free every frame from block.
  618.  *
  619.  * @param zone
  620.  * @param frame_idx Index to block
  621.  * @param count Allocated space in block
  622.  */
  623. static void zone_reduce_region(zone_t *zone, pfn_t frame_idx, count_t count)
  624. {
  625.     count_t i;
  626.     __u8 order;
  627.     frame_t *frame;
  628.    
  629.     ASSERT(frame_idx+count < zone->count);
  630.  
  631.     order = zone->frames[frame_idx].buddy_order;
  632.     ASSERT((1 << order) >= count);
  633.  
  634.     /* Reduce all blocks to order 0 */
  635.     for (i=0; i < (1 << order); i++) {
  636.         frame = &zone->frames[i + frame_idx];
  637.         frame->buddy_order = 0;
  638.         if (! frame->refcount)
  639.             frame->refcount = 1;
  640.         ASSERT(frame->refcount == 1);
  641.     }
  642.     /* Free unneeded frames */
  643.     for (i=count; i < (1 << order); i++) {
  644.         zone_frame_free(zone, i + frame_idx);
  645.     }
  646. }
  647.  
  648. /** Merge zones z1 and z2
  649.  *
  650.  * - the zones must be 2 zones with no zone existing in between,
  651.  *   which means that z2 = z1+1
  652.  *
  653.  * - When you create a new zone, the frame allocator configuration does
  654.  *   not to be 2^order size. Once the allocator is running it is no longer
  655.  *   possible, merged configuration data occupies more space :-/
  656.  */
  657. void zone_merge(int z1, int z2)
  658. {
  659.     ipl_t ipl;
  660.     zone_t *zone1, *zone2, *newzone;
  661.     int cframes;
  662.     __u8 order;
  663.     int i;
  664.     pfn_t pfn;
  665.  
  666.     ipl = interrupts_disable();
  667.     spinlock_lock(&zones.lock);
  668.  
  669.     if (z1 < 0 || z1 >= zones.count || z2 < 0 || z2 >= zones.count)
  670.         goto errout;
  671.     /* We can join only 2 zones with none existing inbetween */
  672.     if (z2-z1 != 1)
  673.         goto errout;
  674.  
  675.     zone1 = zones.info[z1];
  676.     zone2 = zones.info[z2];
  677.     spinlock_lock(&zone1->lock);
  678.     spinlock_lock(&zone2->lock);
  679.  
  680.     cframes = SIZE2FRAMES(zone_conf_size(zone2->base+zone2->count-zone1->base));
  681.     order = fnzb(cframes) + 1;
  682.  
  683.     /* Allocate zonedata inside one of the zones */
  684.     if (zone_can_alloc(zone1, order))
  685.         pfn = zone1->base + zone_frame_alloc(zone1, order);
  686.     else if (zone_can_alloc(zone2, order))
  687.         pfn = zone2->base + zone_frame_alloc(zone2, order);
  688.     else
  689.         goto errout2;
  690.  
  691.     newzone = (zone_t *)PA2KA(PFN2ADDR(pfn));
  692.  
  693.     _zone_merge(newzone, zone1, zone2);
  694.  
  695.     /* Free unneeded config frames */
  696.     zone_reduce_region(newzone, pfn - newzone->base,  cframes);
  697.     /* Subtract zone information from busy frames */
  698.     newzone->busy_count -= cframes;
  699.  
  700.     /* Replace existing zones in zoneinfo list */
  701.     zones.info[z1] = newzone;
  702.     for (i = z2 + 1; i < zones.count; i++)
  703.         zones.info[i - 1] = zones.info[i];
  704.     zones.count--;
  705.  
  706.     /* Free old zone information */
  707.     return_config_frames(newzone, zone1);
  708.     return_config_frames(newzone, zone2);
  709. errout2:
  710.     /* Nobody is allowed to enter to zone, so we are safe
  711.      * to touch the spinlocks last time */
  712.     spinlock_unlock(&zone1->lock);
  713.     spinlock_unlock(&zone2->lock);
  714. errout:
  715.     spinlock_unlock(&zones.lock);
  716.     interrupts_restore(ipl);
  717. }
  718.  
  719. /**
  720.  * Merge all zones into one big zone
  721.  *
  722.  * It is reasonable to do this on systems whose bios reports parts in chunks,
  723.  * so that we could have 1 zone (it's faster).
  724.  */
  725. void zone_merge_all(void)
  726. {
  727.     int count = zones.count;
  728.  
  729.     while (zones.count > 1 && --count) {
  730.         zone_merge(0,1);
  731.         break;
  732.     }
  733. }
  734.  
  735. /** Create frame zone
  736.  *
  737.  * Create new frame zone.
  738.  *
  739.  * @param start Physical address of the first frame within the zone.
  740.  * @param size Size of the zone. Must be a multiple of FRAME_SIZE.
  741.  * @param conffram Address of configuration frame
  742.  * @param flags Zone flags.
  743.  *
  744.  * @return Initialized zone.
  745.  */
  746. static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
  747. {
  748.     int i;
  749.     __u8 max_order;
  750.  
  751.     spinlock_initialize(&z->lock, "zone_lock");
  752.     z->base = start;
  753.     z->count = count;
  754.     z->flags = flags;
  755.     z->free_count = count;
  756.     z->busy_count = 0;
  757.  
  758.     /*
  759.      * Compute order for buddy system, initialize
  760.      */
  761.     max_order = fnzb(count);
  762.     z->buddy_system = (buddy_system_t *)&z[1];
  763.    
  764.     buddy_system_create(z->buddy_system, max_order,
  765.                 &zone_buddy_system_operations,
  766.                 (void *) z);
  767.    
  768.     /* Allocate frames _after_ the conframe */
  769.     /* Check sizes */
  770.     z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
  771.     for (i = 0; i<count; i++) {
  772.         frame_initialize(&z->frames[i]);
  773.     }
  774.    
  775.     /* Stuffing frames */
  776.     for (i = 0; i < count; i++) {
  777.         z->frames[i].refcount = 0;
  778.         buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
  779.     }
  780. }
  781.  
  782. /** Compute configuration data size for zone */
  783. __address zone_conf_size(count_t count)
  784. {
  785.     int size = sizeof(zone_t) + count*sizeof(frame_t);
  786.     int max_order;
  787.  
  788.     max_order = fnzb(count);
  789.     size += buddy_conf_size(max_order);
  790.     return size;
  791. }
  792.  
  793. /** Create and add zone to system
  794.  *
  795.  * @param confframe Where configuration frame is supposed to be.
  796.  *                  Always check, that we will not disturb the kernel and possibly init.
  797.  *                  If confframe is given _outside_ this zone, it is expected,
  798.  *                  that the area is already marked BUSY and big enough
  799.  *                  to contain zone_conf_size() amount of data
  800.  *
  801.  * @return Zone number or -1 on error
  802.  */
  803. int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
  804. {
  805.     zone_t *z;
  806.     __address addr;
  807.     count_t confcount;
  808.     int i;
  809.     int znum;
  810.  
  811.     /* Theoretically we could have here 0, practically make sure
  812.      * nobody tries to do that. If some platform requires, remove
  813.      * the assert
  814.      */
  815.     ASSERT(confframe);
  816.     /* If conframe is supposed to be inside our zone, then make sure
  817.      * it does not span kernel & init
  818.      */
  819.     confcount = SIZE2FRAMES(zone_conf_size(count));
  820.     if (confframe >= start && confframe < start+count) {
  821.         for (;confframe < start + count; confframe++) {
  822.             addr = PFN2ADDR(confframe);
  823.             if (overlaps(addr, PFN2ADDR(confcount), KA2PA(config.base), config.kernel_size))
  824.                 continue;
  825.            
  826.             bool overlap = false;
  827.             count_t i;
  828.             for (i = 0; i < init.cnt; i++)
  829.                 if (overlaps(addr, PFN2ADDR(confcount), KA2PA(init.tasks[i].addr), init.tasks[i].size)) {
  830.                     overlap = true;
  831.                     break;
  832.                 }
  833.             if (overlap)
  834.                 continue;
  835.            
  836.             break;
  837.         }
  838.         if (confframe >= start + count)
  839.             panic("Cannot find configuration data for zone.");
  840.     }
  841.  
  842.     z = (zone_t *)PA2KA(PFN2ADDR(confframe));
  843.     zone_construct(start, count, z, flags);
  844.     znum = zones_add_zone(z);
  845.     if (znum == -1)
  846.         return -1;
  847.  
  848.     /* If confdata in zone, mark as unavailable */
  849.     if (confframe >= start && confframe < start+count)
  850.         for (i=confframe; i<confframe+confcount; i++) {
  851.             zone_mark_unavailable(z, i - z->base);
  852.         }
  853.     return znum;
  854. }
  855.  
  856. /***************************************/
  857. /* Frame functions */
  858.  
  859. /** Set parent of frame */
  860. void frame_set_parent(pfn_t pfn, void *data, int hint)
  861. {
  862.     zone_t *zone = find_zone_and_lock(pfn, &hint);
  863.  
  864.     ASSERT(zone);
  865.  
  866.     zone_get_frame(zone, pfn-zone->base)->parent = data;
  867.     spinlock_unlock(&zone->lock);
  868. }
  869.  
  870. void * frame_get_parent(pfn_t pfn, int hint)
  871. {
  872.     zone_t *zone = find_zone_and_lock(pfn, &hint);
  873.     void *res;
  874.  
  875.     ASSERT(zone);
  876.     res = zone_get_frame(zone, pfn - zone->base)->parent;
  877.    
  878.     spinlock_unlock(&zone->lock);
  879.     return res;
  880. }
  881.  
  882. /** Allocate power-of-two frames of physical memory.
  883.  *
  884.  * @param flags Flags for host zone selection and address processing.
  885.  * @param order Allocate exactly 2^order frames.
  886.  * @param pzone Preferred zone
  887.  *
  888.  * @return Allocated frame.
  889.  */
  890. pfn_t frame_alloc_generic(__u8 order, int flags, int * status, int *pzone)
  891. {
  892.     ipl_t ipl;
  893.     int freed;
  894.     pfn_t v;
  895.     zone_t *zone;
  896.    
  897. loop:
  898.     ipl = interrupts_disable();
  899.     /*
  900.      * First, find suitable frame zone.
  901.      */
  902.     zone = find_free_zone_lock(order,pzone);
  903.     /* If no memory, reclaim some slab memory,
  904.        if it does not help, reclaim all */
  905.     if (!zone && !(flags & FRAME_NO_RECLAIM)) {
  906.         freed = slab_reclaim(0);
  907.         if (freed)
  908.             zone = find_free_zone_lock(order,pzone);
  909.         if (!zone) {
  910.             freed = slab_reclaim(SLAB_RECLAIM_ALL);
  911.             if (freed)
  912.                 zone = find_free_zone_lock(order,pzone);
  913.         }
  914.     }
  915.     if (!zone) {
  916.         if (flags & FRAME_PANIC)
  917.             panic("Can't allocate frame.\n");
  918.        
  919.         /*
  920.          * TODO: Sleep until frames are available again.
  921.          */
  922.         interrupts_restore(ipl);
  923.  
  924.         if (flags & FRAME_ATOMIC) {
  925.             ASSERT(status != NULL);
  926.             if (status)
  927.                 *status = FRAME_NO_MEMORY;
  928.             return NULL;
  929.         }
  930.        
  931.         panic("Sleep not implemented.\n");
  932.         goto loop;
  933.     }
  934.     v = zone_frame_alloc(zone,order);
  935.     v += zone->base;
  936.  
  937.     spinlock_unlock(&zone->lock);
  938.     interrupts_restore(ipl);
  939.  
  940.     if (status)
  941.         *status = FRAME_OK;
  942.     return v;
  943. }
  944.  
  945. /** Free a frame.
  946.  *
  947.  * Find respective frame structure for supplied addr.
  948.  * Decrement frame reference count.
  949.  * If it drops to zero, move the frame structure to free list.
  950.  *
  951.  * @param frame Frame no to be freed.
  952.  */
  953. void frame_free(pfn_t pfn)
  954. {
  955.     ipl_t ipl;
  956.     zone_t *zone;
  957.  
  958.     ipl = interrupts_disable();
  959.    
  960.     /*
  961.      * First, find host frame zone for addr.
  962.      */
  963.     zone = find_zone_and_lock(pfn,NULL);
  964.     ASSERT(zone);
  965.    
  966.     zone_frame_free(zone, pfn-zone->base);
  967.    
  968.     spinlock_unlock(&zone->lock);
  969.     interrupts_restore(ipl);
  970. }
  971.  
  972.  
  973.  
  974. /** Mark given range unavailable in frame zones */
  975. void frame_mark_unavailable(pfn_t start, count_t count)
  976. {
  977.     int i;
  978.     zone_t *zone;
  979.     int prefzone = 0;
  980.    
  981.     for (i=0; i < count; i++) {
  982.         zone = find_zone_and_lock(start+i,&prefzone);
  983.         if (!zone) /* PFN not found */
  984.             continue;
  985.         zone_mark_unavailable(zone, start+i-zone->base);
  986.  
  987.         spinlock_unlock(&zone->lock);
  988.     }
  989. }
  990.  
  991. /** Initialize physical memory management
  992.  *
  993.  * Initialize physical memory managemnt.
  994.  */
  995. void frame_init(void)
  996. {
  997.     if (config.cpu_active == 1) {
  998.         zones.count = 0;
  999.         spinlock_initialize(&zones.lock,"zones_glob_lock");
  1000.     }
  1001.     /* Tell the architecture to create some memory */
  1002.     frame_arch_init();
  1003.     if (config.cpu_active == 1) {
  1004.         pfn_t firstframe = ADDR2PFN(KA2PA(config.base));
  1005.         pfn_t lastframe = ADDR2PFN(KA2PA(config.base+config.kernel_size));
  1006.         frame_mark_unavailable(firstframe,lastframe-firstframe+1);
  1007.        
  1008.         count_t i;
  1009.         for (i = 0; i < init.cnt; i++)
  1010.             frame_mark_unavailable(ADDR2PFN(KA2PA(init.tasks[i].addr)), SIZE2FRAMES(init.tasks[i].size));
  1011.     }
  1012. }
  1013.  
  1014.  
  1015.  
  1016. /** Prints list of zones
  1017.  *
  1018.  */
  1019. void zone_print_list(void) {
  1020.     zone_t *zone = NULL;
  1021.     int i;
  1022.     ipl_t ipl;
  1023.  
  1024.     ipl = interrupts_disable();
  1025.     spinlock_lock(&zones.lock);
  1026.     printf("#  Base address\tFree Frames\tBusy Frames\n");
  1027.     printf("   ------------\t-----------\t-----------\n");
  1028.     for (i = 0; i < zones.count; i++) {
  1029.         zone = zones.info[i];
  1030.         spinlock_lock(&zone->lock);
  1031.         printf("%d: %.*p \t%10zd\t%10zd\n", i, sizeof(__address) * 2, PFN2ADDR(zone->base), zone->free_count, zone->busy_count);
  1032.         spinlock_unlock(&zone->lock);
  1033.     }
  1034.     spinlock_unlock(&zones.lock);
  1035.     interrupts_restore(ipl);
  1036. }
  1037.  
  1038. /** Prints zone details
  1039.  *
  1040.  * @param base Zone base address OR zone number
  1041.  */
  1042. void zone_print_one(int num) {
  1043.     zone_t *zone = NULL;
  1044.     ipl_t ipl;
  1045.     int i;
  1046.  
  1047.     ipl = interrupts_disable();
  1048.     spinlock_lock(&zones.lock);
  1049.  
  1050.     for (i = 0; i < zones.count; i++) {
  1051.         if (i == num || PFN2ADDR(zones.info[i]->base) == num) {
  1052.             zone = zones.info[i];
  1053.             break;
  1054.         }
  1055.     }
  1056.     if (!zone) {
  1057.         printf("Zone not found.\n");
  1058.         goto out;
  1059.     }
  1060.    
  1061.     spinlock_lock(&zone->lock);
  1062.     printf("Memory zone information\n");
  1063.     printf("Zone base address: %#.*p\n", sizeof(__address) * 2, PFN2ADDR(zone->base));
  1064.     printf("Zone size: %zd frames (%zdK)\n", zone->count, ((zone->count) * FRAME_SIZE) >> 10);
  1065.     printf("Allocated space: %zd frames (%zdK)\n", zone->busy_count, (zone->busy_count * FRAME_SIZE) >> 10);
  1066.     printf("Available space: %zd (%zdK)\n", zone->free_count, (zone->free_count * FRAME_SIZE) >> 10);
  1067.     buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
  1068.    
  1069.     spinlock_unlock(&zone->lock);
  1070. out:
  1071.     spinlock_unlock(&zones.lock);
  1072.     interrupts_restore(ipl);
  1073. }
  1074.  
  1075.