Changeset 84dd253 in mainline for src/mm/frame.c

Timestamp:

2005-09-21T13:37:50Z (20 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

aed4eca

Parents:

fcacfb7

Message:

Physical memory management work.
New frame allocator.
Some architectures need to have bigger heap.

File:

• src/mm/frame.c (modified) (2 diffs)

src/mm/frame.c

@@ -27 +27 @@
  */
 
+#include <typedefs.h>
 #include <arch/types.h>
-#include <func.h>
-
 #include <mm/heap.h>
 #include <mm/frame.h>
-#include <mm/page.h>
 #include <mm/vm.h>
-#include <arch/mm/page.h>
-
-#include <config.h>
-#include <memstr.h>
-
 #include <panic.h>
 #include <debug.h>
-
+#include <list.h>
 #include <synch/spinlock.h>
-
 #include <arch/asm.h>
 #include <arch.h>
 
-count_t frames = 0;
-count_t frames_free;
-
-__u8 *frame_bitmap;
-count_t frame_bitmap_octets;
-
-static spinlock_t framelock;
-
 spinlock_t zone_head_lock;       /**< this lock protects zone_head list */
 link_t zone_head;                /**< list of all zones in the system */
 
-
+/** Initialize physical memory management
+ *
+ * Initialize physical memory managemnt.
+ */
 void frame_init(void)
 {
         if (config.cpu_active == 1) {
                 zone_init();
-
-                /*
-                 * The bootstrap processor will allocate all necessary memory for frame allocation.
-                 */
-
-                frames = config.memory_size / FRAME_SIZE;
-                frame_bitmap_octets = frames / 8 + (frames % 8 > 0);
-                frame_bitmap = (__u8 *) malloc(frame_bitmap_octets);
-                if (!frame_bitmap)
-                        panic("malloc/frame_bitmap\n");
-
-                /*
-                 * Mark all frames free.
-                 */
-                memsetb((__address) frame_bitmap, frame_bitmap_octets, 0);
-                frames_free = frames;
-        }
-
-        /*
-         * No frame allocations/reservations prior this point.
-         */
+        }
 
         frame_arch_init();
-
+        
         if (config.cpu_active == 1) {
-                /*
-                 * Create the memory address space map. Marked frames and frame
-                 * regions cannot be used for allocation.
-                 */
-                frame_region_not_free(config.base, config.base + config.kernel_size);
-        }
-}
-
-/*
- * Allocate a frame.
+                frame_region_not_free(config.base, config.base + config.kernel_size + CONFIG_STACK_SIZE);
+        }       
+}
+
+/** Allocate a frame
+ *
+ * Allocate a frame of physical memory.
+ *
+ * @param flags Flags for host zone selection and address processing.
+ *
+ * @return Allocated frame.
  */
 __address frame_alloc(int flags)
 {
-        int i;
         pri_t pri;
+        link_t *cur, *tmp;
+        zone_t *z;
+        zone_t *zone = NULL;
+        frame_t *frame = NULL;
+        __address v;
         
 loop:
         pri = cpu_priority_high();
-        spinlock_lock(&framelock);
-        if (frames_free) {
-                for (i=0; i < frames; i++) {
-                        int m, n;
-                
-                        m = i / 8;
-                        n = i % 8;
-
-                        if ((frame_bitmap[m] & (1<<n)) == 0) {
-                                frame_bitmap[m] |= (1<<n);
-                                frames_free--;
-                                spinlock_unlock(&framelock);
-                                cpu_priority_restore(pri);
-                                if (flags & FRAME_KA) return PA2KA(i*FRAME_SIZE);
-                                return i*FRAME_SIZE;
-                        }
-                }
-                panic("frames_free inconsistent (%d)\n", frames_free);
-        }
-        spinlock_unlock(&framelock);
+        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);
+                
+                spinlock_lock(&z->lock);
+                /*
+                 * Check if the zone has any free frames.
+                 */
+                if (z->free_count) {
+                        zone = z;
+                        break;
+                }
+                spinlock_unlock(&z->lock);
+        }
+        
+        if (!zone) {
+                if (flags & FRAME_PANIC)
+                        panic("Can't allocate frame.\n");
+                
+                /*
+                 * TODO: Sleep until frames are available again.
+                 */
+                spinlock_unlock(&zone_head_lock);
+                cpu_priority_restore(pri);
+
+                panic("Sleep not implemented.\n");
+                goto loop;
+        }
+                
+        tmp = zone->free_head.next;
+        frame = list_get_instance(tmp, frame_t, link);
+
+        frame->refcount++;
+        list_remove(tmp);                       /* remove frame from free_head */
+        list_append(tmp, &zone->busy_head);     /* append frame to busy_head */
+        zone->free_count--;
+        zone->busy_count++;
+        
+        v = zone->base + (frame - zone->frames) * FRAME_SIZE;
+        
+        if (flags & FRAME_KA)
+                v = PA2KA(v);
+        
+        spinlock_unlock(&zone->lock);
+        
+        spinlock_unlock(&zone_head_lock);
         cpu_priority_restore(pri);
-
-        if (flags & FRAME_PANIC)
-                panic("unable to allocate frame\n");
-                
-        /* TODO: implement sleeping logic here */
-        panic("sleep not supported\n");
-        
-        goto loop;
-}
-
-/*
- * Free a frame.
+        
+        return v;
+}
+
+/** 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)
 {
         pri_t pri;
-        __u32 frame;
-
+        link_t *cur;
+        zone_t *z;
+        zone_t *zone = NULL;
+        frame_t *frame;
+        
+        ASSERT(addr % FRAME_SIZE == 0);
+        
         pri = cpu_priority_high();
-        spinlock_lock(&framelock);
-        
-        frame = IS_KA(addr) ? KA2PA(addr) : addr;
-        frame /= FRAME_SIZE;
-        if (frame < frames) {
-                int m, n;
-        
-                m = frame / 8;
-                n = frame % 8;
-        
-                if (frame_bitmap[m] & (1<<n)) {
-                        frame_bitmap[m] &= ~(1<<n);
-                        frames_free++;
-                }
-                else panic("frame already free\n");
-        }
-        else panic("frame number too big\n");
-        
-        spinlock_unlock(&framelock);
+        spinlock_lock(&zone_head_lock);
+        
+        /*
+         * First, find host frame zone for addr.
+         */
+        for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
+                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 = &zone->frames[(addr - zone->base)/FRAME_SIZE];
+        ASSERT(frame->refcount);
+
+        if (!--frame->refcount) {
+                list_remove(&frame->link);                      /* remove frame from busy_head */
+                list_append(&frame->link, &zone->free_head);    /* append frame to free_head */
+                zone->free_count++;
+                zone->busy_count--;
+        }
+        
+        spinlock_unlock(&zone->lock);   
+        
+        spinlock_unlock(&zone_head_lock);
         cpu_priority_restore(pri);
 }
 
-/*
- * Don't use this function for normal allocation. Use frame_alloc() instead.
- * Use this function to declare that some special frame is not free.
+/** Mark frame not free.
+ *
+ * Find respective frame structrue for supplied addr.
+ * Increment frame reference count and move the frame structure to busy list.
+ *
+ * @param addr Address of the frame to be marked. It must be a multiple of FRAME_SIZE.
  */
 void frame_not_free(__address addr)
 {
         pri_t pri;
-        __u32 frame;
+        link_t *cur;
+        zone_t *z;
+        zone_t *zone = NULL;
+        frame_t *frame;
+        
+        ASSERT(addr % FRAME_SIZE == 0);
         
         pri = cpu_priority_high();
-        spinlock_lock(&framelock);
-        frame = IS_KA(addr) ? KA2PA(addr) : addr;
-        frame /= FRAME_SIZE;
-        if (frame < frames) {
-                int m, n;
-
-                m = frame / 8;
-                n = frame % 8;
-        
-                if ((frame_bitmap[m] & (1<<n)) == 0) {  
-                        frame_bitmap[m] |= (1<<n);
-                        frames_free--;  
-                }
-        }
-        spinlock_unlock(&framelock);
+        spinlock_lock(&zone_head_lock);
+        
+        /*
+         * First, find host frame zone for addr.
+         */
+        for (cur = zone_head.next; cur != &zone_head; cur = cur->next) {
+                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 = &zone->frames[(addr - zone->base)/FRAME_SIZE];
+
+        if (!frame->refcount) {
+                frame->refcount++;
+
+                list_remove(&frame->link);                      /* remove frame from free_head */
+                list_append(&frame->link, &zone->busy_head);    /* append frame to busy_head */
+                zone->free_count--;
+                zone->busy_count++;
+        }
+        
+        spinlock_unlock(&zone->lock);   
+        
+        spinlock_unlock(&zone_head_lock);
         cpu_priority_restore(pri);
 }
 
+/** Mark frame region not free.
+ *
+ * Mark frame region not free.
+ *
+ * @param start First address.
+ * @param stop Last address.
+ */
 void frame_region_not_free(__address start, __address stop)
 {
-        __address a;
-
-        start /= FRAME_SIZE;
-        stop /= FRAME_SIZE;
-        for (a = start; a <= stop; a++)
-                frame_not_free(a * FRAME_SIZE);
-}
+        __address a;
+
+        start /= FRAME_SIZE;
+        stop /= FRAME_SIZE;
+        for (a = start; a <= stop; a++)
+                frame_not_free(a * FRAME_SIZE);
+}
+
 
 /** Initialize zonekeeping
@@ -297 +362 @@
         frame->refcount = 0;
         link_initialize(&frame->link);
-        frame->zone = zone;
-}
-
-/** Get address of physical frame from its frame structure
- *
- * Get address of physical frame from its frame structure.
- *
- * @param frame Frame structure of the queried frame address.
- *
- * @return Address of frame associated with the argument.
- */
-__address frame_get_address(frame_t *frame)
-{
-        __address v;
-        zone_t *z;
-        pri_t pri;
-        
-        z = frame->zone;
-        
-        pri = cpu_priority_high();
-        spinlock_lock(&z->lock);
-
-        v = z->base + (frame - z->frames) * FRAME_SIZE;
-        
-        if (z->flags & FRAME_KA)
-                v = PA2KA(v);
-
-        spinlock_unlock(&z->lock);
-        cpu_priority_restore(pri);
-        
-        return v;
-}
+}