Import backup from 2005-09-11

kernel/mm/vmm.c

@@ -41,6 +41,7 @@ void	vmm_init()
 		vmm_map_range((void*)mb_modules[i].mod_start, (void*)mb_modules[i].mod_end - 1, mb_modules[i].mod_start - VIRT_OFFSET);
 	for (i = 0; i < VMM_HE_TYPES; i++)
 	{
+		heapEntryQueues[i].count = 0;
 		heapEntryQueues[i].head = &heapEntryHeadNodes[i];
 		heapEntryHeadNodes[i].next = &heapEntryTailNodes[i];
 		heapEntryTailNodes[i].prev = &heapEntryHeadNodes[i];
@@ -159,6 +160,8 @@ void	*kmalloc(u32_t size)
 	void *attempt = vmm_getFreeChunk(size);
 	if (attempt)
 	{
+		if ((u32_t)attempt == 0xd000c5e4)
+			kprintf("vmm.c: attempt = 0x%x\n", attempt);
 		k_leave_critical();
 		return attempt;
 	}
@@ -168,6 +171,8 @@ void	*kmalloc(u32_t size)
 		return NULL;		//we could not get any more heap memory
 	}
 	attempt = vmm_getFreeChunk(size);
+	if ((u32_t)attempt == 0xd000c5e4)
+		kprintf("vmm.c: attempt = 0x%x\n", attempt);
 	k_leave_critical();
 	return attempt;
 }
@@ -338,17 +343,17 @@ void *vmm_getFreeChunk(u32_t size)
 		}
 		he = (HeapEntry_t *)he->next;
 	}
-	if (good)
-	{
-		HeapEntry_t *newHE = vmm_getUnusedEntry();
-		newHE->base = good->base;
-		newHE->length = size;
-		good->base += size;
-		good->length -= size;
-		vmm_addToQueue(VMM_HE_USED, heapEntryQueues[VMM_HE_USED].head, newHE);
-		return newHE->base;
-	}
-	return NULL;
+	if (!good)
+		return NULL;
+	HeapEntry_t *newHE = vmm_getUnusedEntry();
+	newHE->base = good->base;
+	newHE->length = size;
+	newHE->next = NULL;
+	newHE->prev = NULL;
+	good->base += size;
+	good->length -= size;
+	vmm_addToQueue(VMM_HE_USED, heapEntryQueues[VMM_HE_USED].head, newHE);
+	return newHE->base;
 }
 
 
@@ -379,6 +384,8 @@ int	vmm_moreCore(u32_t size)
 	HeapEntry_t *newHE = vmm_getUnusedEntry();
 	newHE->base = wilderness->base;
 	newHE->length = size;
+	newHE->next = 0;
+	newHE->prev = 0;
 	wilderness->base += size;
 	wilderness->length -= size;
 	if (vmm_coalesceEntry(VMM_HE_FREE, newHE))	// returns 0 on success (coalesced into previous entry)
@@ -438,6 +445,7 @@ void	vmm_heb_init(HeapEntryBlock_t *heb)
 
 
 // This function adds a HeapEntry structure to the queue following 'preceeding' the queue
+// fails if add to tail (add one element before tail node)
 void vmm_addToQueue(u32_t queue, HeapEntry_t *preceeding, HeapEntry_t *he)
 {
 	heapEntryQueues[queue].count += vmm_countHeapEntries(he);
@@ -472,10 +480,13 @@ HeapEntry_t *vmm_followChain(HeapEntry_t *he)
 
 
 // This function breaks an unused chunk from its queue and returns a pointer to it
+// 09/10/05 nasty bug fixed by josh, wasn't adding unused entries when we ran out of them
 HeapEntry_t *vmm_getUnusedEntry()
 {
 	if (heapEntryQueues[VMM_HE_UNUSED].count < 5)
 	{
+		kprintf(" heapEntryQueues[VMM_HE_UNUSED].count = %d\n",
+			heapEntryQueues[VMM_HE_UNUSED].count);
 		HeapEntry_t *he = heapEntryQueues[VMM_HE_HOLE].head->next;
 		HeapEntry_t *wilderness = he;
 		while (he)
@@ -484,14 +495,15 @@ HeapEntry_t *vmm_getUnusedEntry()
 				wilderness = he;
 			he = (HeapEntry_t *)he->next;
 		}
+		if (wilderness->length < 10000)
+		{
+			k_check(-1, "Kernel panic: out of virtual memory\n");
+		}
 		wilderness->length -= 4096;			//strip 4k from the top
 		HeapEntryBlock_t *newHEB = wilderness->base + wilderness->length;
 		vmm_map(newHEB);
 		vmm_heb_init(newHEB);
-		HeapEntry_t *newDesc = vmm_stripUnusedEntry();	//descriptor for the new HEB
-		newDesc->base = newHEB;
-		newDesc->length = 4096;
-		vmm_addToQueue(VMM_HE_USED, heapEntryTailNodes[VMM_HE_USED].prev, newDesc);
+		vmm_addToQueue(VMM_HE_UNUSED, heapEntryTailNodes[VMM_HE_UNUSED].prev, &newHEB->entry[0]);
 	}
 	return vmm_stripUnusedEntry();
 }
@@ -502,6 +514,8 @@ HeapEntry_t *vmm_stripUnusedEntry()
 {
 	HeapEntry_t *he = heapEntryQueues[VMM_HE_UNUSED].head->next;
 	heapEntryQueues[VMM_HE_UNUSED].head->next = he->next;
+	if (! he->next)
+		kprintf(" he->next is NULL\n");
 	((HeapEntry_t *)he->next)->prev = he->prev;
 	heapEntryQueues[VMM_HE_UNUSED].count--;
 	he->next = 0;