WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/mm/frame.c

 /*
  * Copyright (C) 2001-2005 Jakub Jermar
  * Copyright (C) 2005 Sergey Bondari
  * All rights reserved.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
+ *
  * - Redistributions of source code must retain the above copyright
  *   notice, this list of conditions and the following disclaimer.
  * - Redistributions in binary form must reproduce the above copyright
  *   notice, this list of conditions and the following disclaimer in the
  *   documentation and/or other materials provided with the distribution.
  * - The name of the author may not be used to endorse or promote products
  *   derived from this software without specific prior written permission.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <typedefs.h>
 #include <arch/types.h>
 #include <mm/heap.h>
 #include <mm/frame.h>
 #include <mm/as.h>
 #include <panic.h>
 #include <debug.h>
 #include <list.h>
 #include <synch/spinlock.h>
 #include <arch/asm.h>
 #include <arch.h>
 #include <print.h>
 #include <align.h>
 SPINLOCK_INITIALIZE(zone_head_lock);    /**< this lock protects zone_head list */
 LIST_INITIALIZE(zone_head);             /**< list of all zones in the system */
 /** Blacklist containing non-available areas of memory.
+ *
  * This blacklist is used to exclude frames that cannot be allocated
  * (e.g. kernel memory) from available memory map.
  */
 region_t zone_blacklist[ZONE_BLACKLIST_SIZE];
 count_t zone_blacklist_count = 0;
 static struct buddy_system_operations  zone_buddy_system_operations = {
     .find_buddy = zone_buddy_find_buddy,
     .bisect = zone_buddy_bisect,
     .coalesce = zone_buddy_coalesce,
     .set_order = zone_buddy_set_order,
     .get_order = zone_buddy_get_order,
     .mark_busy = zone_buddy_mark_busy,
 };
 /** Initialize physical memory management
+ *
  * Initialize physical memory managemnt.
  */
 void frame_init(void)
+{
     if (config.cpu_active == 1) {
         frame_region_not_free(KA2PA(config.base), config.kernel_size);
         if (config.init_size > 0)
             frame_region_not_free(KA2PA(config.init_addr), config.init_size);
+    }
     frame_arch_init();
+}
+/**
+ * Find AND LOCK zone that can allocate order frames
+ *
+ * Assume zone_head_lock is locked.
+ */
+static zone_t * find_free_zone(__u8 order)
+{
+    link_t *cur;
+    zone_t *z;
+    for (cur = zone_head.next; cur != &zone_head;cur = cur->next) {
+        z = list_get_instance(cur, zone_t, link);
+        spinlock_lock(&z->lock);
+        /* Check if the zone has 2^order frames area available  */
+        if (buddy_system_can_alloc(z->buddy_system, order))
+            return z;
+        spinlock_unlock(&z->lock);
+    }
+    return NULL;
+}
 /** Allocate power-of-two frames of physical memory.
+ *
  * @param flags Flags for host zone selection and address processing.
  * @param order Allocate exactly 2^order frames.
+ * @param pzone Pointer to preferred zone pointer, on output it changes
+ *              to the zone that the frame was really allocated to
+ *
  * @return Allocated frame.
  */
-__address frame_alloc(int flags, __u8 order, int * status)
+__address frame_alloc(int flags, __u8 order, int * status, zone_t **pzone)
+{
     ipl_t ipl;
-    link_t *cur, *tmp;
+    link_t *tmp;
-    zone_t *z;
     zone_t *zone = NULL;
     frame_t *frame = NULL;
     __address v;
 loop:
     ipl = interrupts_disable();
     spinlock_lock(&zone_head_lock);
     /*
      * First, find suitable frame zone.
      */
-    for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
-        z = list_get_instance(cur, zone_t, link);
+    if (pzone && *pzone) {
-        spinlock_lock(&z->lock);
+        spinlock_lock(&(*pzone)->lock);
-        /* Check if the zone has 2^order frames area available  */
-        if (buddy_system_can_alloc(z->buddy_system, order)) {
+        if (!buddy_system_can_alloc((*pzone)->buddy_system, order))
-            zone = z;
+            spinlock_unlock(&(*pzone)->lock);
-            break;
-        }
+        else
-        spinlock_unlock(&z->lock);
+            zone = *pzone;
+    }
+    if (!zone) {
+        zone = find_free_zone(order);
+        /* If no memory, reclaim some slab memory,
+           if it does not help, reclaim all */
+        if (!zone && !(flags & FRAME_NO_RECLAIM))
+            if (slab_reclaim(0) || slab_reclaim(SLAB_RECLAIM_ALL))
+                zone = find_free_zone(order);
+    }
     if (!zone) {
         if (flags & FRAME_PANIC)
             panic("Can't allocate frame.\n");
         /*
          * TODO: Sleep until frames are available again.
          */
         spinlock_unlock(&zone_head_lock);
         interrupts_restore(ipl);
         if (flags & FRAME_ATOMIC) {
             ASSERT(status != NULL);
             *status = FRAME_NO_MEMORY;
             return NULL;
+        }
         panic("Sleep not implemented.\n");
         goto loop;
+    }
     /* Allocate frames from zone buddy system */
     tmp = buddy_system_alloc(zone->buddy_system, order);
     ASSERT(tmp);
     /* Update zone information. */
     zone->free_count -= (1 << order);
     zone->busy_count += (1 << order);
     /* Frame will be actually a first frame of the block. */
     frame = list_get_instance(tmp, frame_t, buddy_link);
     /* get frame address */
     v = FRAME2ADDR(zone, frame);
     spinlock_unlock(&zone->lock);
     spinlock_unlock(&zone_head_lock);
     interrupts_restore(ipl);
     ASSERT(v == ALIGN_UP(v, FRAME_SIZE << order));
     if (flags & FRAME_KA)
         v = PA2KA(v);
     if (flags & FRAME_ATOMIC) {
         ASSERT(status != NULL);
         *status = FRAME_OK;
+    }
+    if (pzone)
+        *pzone = zone;
     return v;
+}
+/** Convert address to zone pointer
+ *
+ * Assume zone_head_lock is held
+ *
+ * @param addr Physical address
+ * @param lock If true, lock the zone
+ */
+static zone_t * addr2zone(__address addr, int lock)
+{
+    link_t *cur;
+    zone_t *z = NULL;
+    for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
+        z = list_get_instance(cur, zone_t, link);
+        spinlock_lock(&z->lock);
+        /*
+         * Check if addr belongs to z.
+         */
+        if ((addr >= z->base) && (addr <= z->base + (z->free_count + z->busy_count) * FRAME_SIZE)) {
+            if (!lock)
+                spinlock_unlock(&z->lock);
+            return z;
+        }
+        spinlock_unlock(&z->lock);
+    }
+    panic("Cannot find addr2zone: 0x%X", addr);
+}
+/** Return frame_t structure corresponding to address
+ *
+ *
+ */
+frame_t * frame_addr2frame(__address addr)
+{
+    ipl_t ipl;
+    frame_t *frame;
+    zone_t *zone;
+    if (IS_KA(addr))
+        addr = KA2PA(addr);
+    /* Disable interrupts to avoid deadlocks with interrupt handlers */
+    ipl = interrupts_disable();
+    spinlock_lock(&zone_head_lock);
+    zone = addr2zone(addr,0);
+    frame = ADDR2FRAME(zone, addr);
+    spinlock_unlock(&zone_head_lock);
+    interrupts_restore(ipl);
+    return frame;
+}
 /** Free a frame.
+ *
  * Find respective frame structrue for supplied addr.
  * Decrement frame reference count.
  * If it drops to zero, move the frame structure to free list.
+ *
  * @param addr Address of the frame to be freed. It must be a multiple of FRAME_SIZE.
  */
 void frame_free(__address addr)
+{
     ipl_t ipl;
-    link_t *cur;
-    zone_t *z;
+    zone_t *zone;
-    zone_t *zone = NULL;
     frame_t *frame;
     int order;
     ASSERT(addr % FRAME_SIZE == 0);
+    if (IS_KA(addr))
+        addr = KA2PA(addr);
     ipl = interrupts_disable();
     spinlock_lock(&zone_head_lock);
     /*
      * First, find host frame zone for addr.
      */
-    for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
+    zone = addr2zone(addr, 1); /* This locks the zone automatically */
-        z = list_get_instance(cur, zone_t, link);
-        spinlock_lock(&z->lock);
-        if (IS_KA(addr))
-            addr = KA2PA(addr);
-        /*
-         * Check if addr belongs to z.
-         */
-        if ((addr >= z->base) && (addr <= z->base + (z->free_count + z->busy_count) * FRAME_SIZE)) {
-            zone = z;
-            break;
-        }
-        spinlock_unlock(&z->lock);
-    }
-    ASSERT(zone != NULL);
     frame = ADDR2FRAME(zone, addr);
     /* remember frame order */
     order = frame->buddy_order;
     ASSERT(frame->refcount);
     if (!--frame->refcount) {
         buddy_system_free(zone->buddy_system, &frame->buddy_link);
+    }
     /* Update zone information. */
     zone->free_count += (1 << order);
     zone->busy_count -= (1 << order);
     spinlock_unlock(&zone->lock);
     spinlock_unlock(&zone_head_lock);
     interrupts_restore(ipl);
+}
 /** Mark frame region not free.
+ *
  * Mark frame region not free.
+ *
  * @param base Base address of non-available region.
  * @param size Size of non-available region.
  */
 void frame_region_not_free(__address base, size_t size)
+{
     index_t index;
     index = zone_blacklist_count++;
     /* Force base to the nearest lower address frame boundary. */
     base = ALIGN_DOWN(base, FRAME_SIZE);
     /* Align size to frame boundary. */
     size = ALIGN_UP(size, FRAME_SIZE);
     ASSERT(index < ZONE_BLACKLIST_SIZE);
     zone_blacklist[index].base = base;
     zone_blacklist[index].size = size;
+}
 /** Create frame zones in region of available memory.
+ *
  * Avoid any black listed areas of non-available memory.
  * Assume that the black listed areas cannot overlap
  * one another or cross available memory region boundaries.
+ *
  * @param base Base address of available memory region.
  * @param size Size of the region.
  */
 void zone_create_in_region(__address base, size_t size) {
     int i;
     zone_t * z;
     __address s;
     size_t sz;
     ASSERT(base % FRAME_SIZE == 0);
     ASSERT(size % FRAME_SIZE == 0);
     if (!size)
         return;
     for (i = 0; i < zone_blacklist_count; i++) {
         if (zone_blacklist[i].base >= base && zone_blacklist[i].base < base + size) {
             s = base; sz = zone_blacklist[i].base - base;
             ASSERT(base != s || sz != size);
             zone_create_in_region(s, sz);
             s = zone_blacklist[i].base + zone_blacklist[i].size;
             sz = (base + size) - (zone_blacklist[i].base + zone_blacklist[i].size);
             ASSERT(base != s || sz != size);
             zone_create_in_region(s, sz);
             return;
+        }
+    }
     z = zone_create(base, size, 0);
     if (!z) {
         panic("Cannot allocate zone (base=%P, size=%d).\n", base, size);
+    }
     zone_attach(z);
+}
 /** Create frame zone
+ *
  * Create new frame zone.
+ *
  * @param start Physical address of the first frame within the zone.
  * @param size Size of the zone. Must be a multiple of FRAME_SIZE.
  * @param flags Zone flags.
+ *
  * @return Initialized zone.
  */
 zone_t * zone_create(__address start, size_t size, int flags)
+{
     zone_t *z;
     count_t cnt;
     int i;
     __u8 max_order;
     ASSERT(start % FRAME_SIZE == 0);
     ASSERT(size % FRAME_SIZE == 0);
     cnt = size / FRAME_SIZE;
     z = (zone_t *) early_malloc(sizeof(zone_t));
     if (z) {
         link_initialize(&z->link);
         spinlock_initialize(&z->lock, "zone_lock");
         z->base = start;
         z->base_index = start / FRAME_SIZE;
         z->flags = flags;
         z->free_count = cnt;
         z->busy_count = 0;
         z->frames = (frame_t *) early_malloc(cnt * sizeof(frame_t));
         if (!z->frames) {
             early_free(z);
             return NULL;
+        }
         for (i = 0; i<cnt; i++) {
             frame_initialize(&z->frames[i], z);
+        }
         /*
          * Create buddy system for the zone
          */
         for (max_order = 0; cnt >> max_order; max_order++)
+            ;
         z->buddy_system = buddy_system_create(max_order, &zone_buddy_system_operations, (void *) z);
         /* Stuffing frames */
         for (i = 0; i<cnt; i++) {
             z->frames[i].refcount = 0;
             buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
+        }
+    }
     return z;
+}
 /** Attach frame zone
+ *
  * Attach frame zone to zone list.
+ *
  * @param zone Zone to be attached.
  */
 void zone_attach(zone_t *zone)
+{
     ipl_t ipl;
     ipl = interrupts_disable();
     spinlock_lock(&zone_head_lock);
     list_append(&zone->link, &zone_head);
     spinlock_unlock(&zone_head_lock);
     interrupts_restore(ipl);
+}
 /** Initialize frame structure
+ *
  * Initialize frame structure.
+ *
  * @param frame Frame structure to be initialized.
  * @param zone Host frame zone.
  */
 void frame_initialize(frame_t *frame, zone_t *zone)
+{
     frame->refcount = 1;
     frame->buddy_order = 0;
+}
 /** Buddy system find_buddy implementation
+ *
  * @param b Buddy system.
  * @param block Block for which buddy should be found
+ *
  * @return Buddy for given block if found
  */
 link_t * zone_buddy_find_buddy(buddy_system_t *b, link_t * block) {
     frame_t * frame;
     zone_t * zone;
     index_t index;
     bool is_left, is_right;
     frame = list_get_instance(block, frame_t, buddy_link);
     zone = (zone_t *) b->data;
     ASSERT(IS_BUDDY_ORDER_OK(FRAME_INDEX_ABS(zone, frame), frame->buddy_order));
     is_left = IS_BUDDY_LEFT_BLOCK_ABS(zone, frame);
     is_right = IS_BUDDY_RIGHT_BLOCK_ABS(zone, frame);
     ASSERT(is_left ^ is_right);
     if (is_left) {
         index = (FRAME_INDEX(zone, frame)) + (1 << frame->buddy_order);
     } else { // if (is_right)
         index = (FRAME_INDEX(zone, frame)) - (1 << frame->buddy_order);
+    }
     if (FRAME_INDEX_VALID(zone, index)) {
         if (    zone->frames[index].buddy_order == frame->buddy_order &&
             zone->frames[index].refcount == 0) {
             return &zone->frames[index].buddy_link;
+        }
+    }
     return NULL;
+}
 /** Buddy system bisect implementation
+ *
  * @param b Buddy system.
  * @param block Block to bisect
+ *
  * @return right block
  */
 link_t * zone_buddy_bisect(buddy_system_t *b, link_t * block) {
     frame_t * frame_l, * frame_r;
     frame_l = list_get_instance(block, frame_t, buddy_link);
     frame_r = (frame_l + (1 << (frame_l->buddy_order - 1)));
     return &frame_r->buddy_link;
+}
 /** Buddy system coalesce implementation
+ *
  * @param b Buddy system.
  * @param block_1 First block
  * @param block_2 First block's buddy
+ *
  * @return Coalesced block (actually block that represents lower address)
  */
 link_t * zone_buddy_coalesce(buddy_system_t *b, link_t * block_1, link_t * block_2) {
     frame_t * frame1, * frame2;
     frame1 = list_get_instance(block_1, frame_t, buddy_link);
     frame2 = list_get_instance(block_2, frame_t, buddy_link);
     return frame1 < frame2 ? block_1 : block_2;
+}
 /** Buddy system set_order implementation
+ *
  * @param b Buddy system.
  * @param block Buddy system block
  * @param order Order to set
  */
 void zone_buddy_set_order(buddy_system_t *b, link_t * block, __u8 order) {
     frame_t * frame;
     frame = list_get_instance(block, frame_t, buddy_link);
     frame->buddy_order = order;
+}
 /** Buddy system get_order implementation
+ *
  * @param b Buddy system.
  * @param block Buddy system block
+ *
  * @return Order of block
  */
 __u8 zone_buddy_get_order(buddy_system_t *b, link_t * block) {
     frame_t * frame;
     frame = list_get_instance(block, frame_t, buddy_link);
     return frame->buddy_order;
+}
 /** Buddy system mark_busy implementation
+ *
  * @param b Buddy system
  * @param block Buddy system block
+ *
  */
 void zone_buddy_mark_busy(buddy_system_t *b, link_t * block) {
     frame_t * frame;
     frame = list_get_instance(block, frame_t, buddy_link);
     frame->refcount = 1;
+}
 /** Prints list of zones
+ *
  */
 void zone_print_list(void) {
     zone_t *zone = NULL;
     link_t *cur;
     ipl_t ipl;
     ipl = interrupts_disable();
     spinlock_lock(&zone_head_lock);
     printf("Base address\tFree Frames\tBusy Frames\n");
     printf("------------\t-----------\t-----------\n");
     for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
         zone = list_get_instance(cur, zone_t, link);
         spinlock_lock(&zone->lock);
         printf("%L\t%d\t\t%d\n",zone->base, zone->free_count, zone->busy_count);
         spinlock_unlock(&zone->lock);
+    }
     spinlock_unlock(&zone_head_lock);
     interrupts_restore(ipl);
+}
 /** Prints zone details
+ *
  * @param base Zone base address
  */
 void zone_print_one(__address base) {
     zone_t *zone = NULL, *z ;
     link_t *cur;
     ipl_t ipl;
     ipl = interrupts_disable();
     spinlock_lock(&zone_head_lock);
     for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
         z = list_get_instance(cur, zone_t, link);
         if (base == z->base) {
             zone = z;
             break;
+        }
+    }
     if (!zone) {
         spinlock_unlock(&zone_head_lock);
         interrupts_restore(ipl);
         printf("No zone with address %X\n", base);
         return;
+    }
     spinlock_lock(&zone->lock);
     printf("Memory zone information\n\n");
     printf("Zone base address: %P\n", zone->base);
     printf("Zone size: %d frames (%dK)\n", zone->free_count + zone->busy_count, ((zone->free_count + zone->busy_count) * FRAME_SIZE) >> 10);
     printf("Allocated space: %d frames (%dK)\n", zone->busy_count, (zone->busy_count * FRAME_SIZE) >> 10);
     printf("Available space: %d (%dK)\n", zone->free_count, (zone->free_count * FRAME_SIZE) >> 10);
     printf("\nBuddy allocator structures:\n\n");
     buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
     spinlock_unlock(&zone->lock);
     spinlock_unlock(&zone_head_lock);
     interrupts_restore(ipl);
+}

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/mm/frame.c – Rev 759 → 762