changed vma_list order

include/metalsvm/malloc.h

@@ -29,9 +29,9 @@ extern "C" {
 /// Binary exponent of maximal size for kmalloc()
 #define BUDDY_MAX	32 // 4 GB
 /// Binary exponent of minimal buddy size
-#define BUDDY_MIN	4  // 16 Byte >= sizeof(buddy_prefix_t)
+#define BUDDY_MIN	3  // 8 Byte >= sizeof(buddy_t)
-/// Binary exponent of the size which we allocate at least in one call to buddy_fill();
+/// Binary exponent of the size which we allocate with buddy_fill()
-#define BUDDY_ALLOC	17 // 128 KByte >= PAGE_SHIFT, TODO: add Huge Page support?
+#define BUDDY_ALLOC	15 // 32 KByte >= PAGE_SIZE
 
 #define BUDDY_LISTS	(BUDDY_MAX-BUDDY_MIN+1)
 #define BUDDY_MAGIC	0xBABE

include/metalsvm/vma.h

@@ -49,10 +49,9 @@ extern "C" {
 #define VMA_HEAP	(VMA_READ|VMA_WRITE|VMA_CACHEABLE)
 
 // boundaries for VAS allocation
-extern const void kernel_end;
+#define VMA_KERN_MIN	PAGE_SIZE	// we skip the first page
-//#define VMA_KERN_MIN	(((size_t) &kernel_end + PAGE_SIZE) & PAGE_MASK)
 #define VMA_KERN_MAX	KERNEL_SPACE
-#define VMA_USER_MAX	(1UL << 47) // TODO
+#define VMA_USER_MAX	PAGE_MAP_PGT
 
 struct vma;
 

mm/vma.c

@@ -30,7 +30,7 @@
  * For bootstrapping we initialize the VMA list with one empty VMA
  * (start == end) and expand this VMA by calls to vma_alloc()
  */
-static vma_t vma_boot = { VMA_KERN_MAX, VMA_KERN_MAX, VMA_HEAP };
+static vma_t vma_boot = { VMA_KERN_MIN, VMA_KERN_MIN, VMA_HEAP };
 static vma_t* vma_list = &vma_boot;
 static spinlock_t vma_lock = SPINLOCK_INIT;
 
@@ -39,7 +39,6 @@ size_t vma_alloc(size_t size, uint32_t flags)
 	task_t* task = per_core(current_task);
 	spinlock_t* lock;
 	vma_t** list;
-	size_t ret = 0;
 
 	kprintf("vma_alloc(0x%lx, 0x%x)\n", size, flags);
 
@@ -56,7 +55,7 @@ size_t vma_alloc(size_t size, uint32_t flags)
 		lock = &task->vma_lock;
 	}
 	else {
-		base = 0;
+		base = VMA_KERN_MIN;
 		limit = VMA_KERN_MAX;
 		list = &vma_list;
 		lock = &vma_lock;
@@ -64,9 +63,9 @@ size_t vma_alloc(size_t size, uint32_t flags)
 
 	spinlock_lock(lock);
 
-	// "last" fit search for free memory area
+	// first fit search for free memory area
-	vma_t* pred = *list;  // vma before current gap
+	vma_t* pred = NULL;  // vma before current gap
-	vma_t* succ = NULL; // vma after current gap
+	vma_t* succ = *list; // vma after current gap
 	do {
 		start = (pred) ? pred->end : base;
 		end = (succ) ? succ->start : limit;
@@ -74,8 +73,8 @@ size_t vma_alloc(size_t size, uint32_t flags)
 		if (end > start && end - start > size)
 			break; // we found a gap
 
-		succ = pred;
+		pred = succ;
-		pred = (pred) ? pred->prev : NULL;
+		succ = (succ) ? succ->next : NULL;
 	} while (pred || succ);
 
 	if (BUILTIN_EXPECT(end > limit || end < start || end - start < size, 0)) {
@@ -83,35 +82,35 @@ size_t vma_alloc(size_t size, uint32_t flags)
 		return 0;
 	}
 
-	// resize existing vma
-	if (succ && succ->flags == flags) {
-		succ->start -= size;
-		ret = succ->start;
-	}
-	// insert new vma
-	else {
-		vma_t* new = kmalloc(sizeof(vma_t));
-		if (BUILTIN_EXPECT(!new, 0))
-			return 0;
 
-		new->start = end-size;
+	if (pred && pred->flags == flags) {
-		new->end = end;
+		pred->end = start+size;
+	}
+	else {
+		// insert new VMA
+		vma_t* new = kmalloc(sizeof(vma_t));
+		if (BUILTIN_EXPECT(!new, 0)) {
+			spinlock_unlock(lock);
+			return 0;
+		}
+
+		new->start = start;
+		new->end = start+size;
 		new->flags = flags;
 		new->next = succ;
 		new->prev = pred;
 
-		if (pred)
-			pred->next = new;
 		if (succ)
 			succ->prev = new;
+		if (pred)
+			pred->next = new;
 		else
 			*list = new;
-
-		ret = new->start;
 	}
 
 	spinlock_unlock(lock);
-	return ret;
+
+	return start;
 }
 
 int vma_free(size_t start, size_t end)
@@ -124,7 +123,7 @@ int vma_free(size_t start, size_t end)
 	if (BUILTIN_EXPECT(start >= end, 0))
 		return -EINVAL;
 
-	if (end <= VMA_KERN_MAX) {
+	if (end < VMA_KERN_MAX) {
 		lock = &vma_lock;
 		list = &vma_list;
 	}
@@ -132,8 +131,6 @@ int vma_free(size_t start, size_t end)
 		lock = &task->vma_lock;
 		list = &task->vma_list;
 	}
-	else
-		return -EINVAL;
 
 	if (BUILTIN_EXPECT(!*list, 0))
 		return -EINVAL;
@@ -144,7 +141,7 @@ int vma_free(size_t start, size_t end)
 	vma = *list;
 	while (vma) {
 		if (start >= vma->start && end <= vma->end) break;
-		vma = vma->prev;
+		vma = vma->next;
 	}
 
 	if (BUILTIN_EXPECT(!vma, 0)) {
@@ -173,13 +170,13 @@ int vma_free(size_t start, size_t end)
 			return -ENOMEM;
 		}
 
-		new->start = end;
-		vma->end = start;
-
 		new->end = vma->end;
+		vma->end = start;
+		new->start = end;
+
 		new->next = vma->next;
-		new->prev = vma;
 		vma->next = new;
+		new->prev = vma;
 	}
 
 	spinlock_unlock(lock);
@@ -211,34 +208,32 @@ int vma_add(size_t start, size_t end, uint32_t flags)
 		lock = &vma_lock;
 
 		// check if address is in kernelspace
-		if (BUILTIN_EXPECT(end > VMA_KERN_MAX, 0))
+		if (BUILTIN_EXPECT(end >= VMA_KERN_MAX, 0))
 			return -EINVAL;
 	}
 
 	spinlock_lock(lock);
 
 	// search gap
-	vma_t* pred = *list;
+	vma_t* pred = NULL;
-	vma_t* succ = NULL;
+	vma_t* succ = *list;
-	while (pred) {
+	do {
 		if ((!pred || pred->end <= start) &&
 		    (!succ || succ->start >= end))
 			break;
 
-		succ = pred;
+		pred = succ;
-		pred = pred->prev;
+		succ = succ->next;
-	}
+	} while (pred || succ);
 
-	// resize existing vma
+	// TODO: check bounds
-	if (pred && pred->end == start && pred->flags == flags)
+
-		pred->end = end;
+	// insert new VMA
-	else if (succ && succ->start == end && succ->flags == flags)
-		succ->start = start;
-	// insert new vma
-	else {
 	vma_t* new = kmalloc(sizeof(vma_t));
-		if (BUILTIN_EXPECT(!new, 0))
+	if (BUILTIN_EXPECT(!new, 0)) {
-			return 0;
+		spinlock_unlock(lock);
+		return -ENOMEM;
+	}
 
 	new->start = start;
 	new->end = end;
@@ -246,13 +241,12 @@ int vma_add(size_t start, size_t end, uint32_t flags)
 	new->next = succ;
 	new->prev = pred;
 
-		if (pred)
-			pred->next = new;
 	if (succ)
 		succ->prev = new;
+	if (pred)
+		pred->next = new;
 	else
 		*list = new;
-	}
 
 	spinlock_unlock(lock);
 
@@ -267,15 +261,15 @@ int copy_vma_list(task_t* task)
 	spinlock_lock(&parent_task->vma_lock);
 	spinlock_lock(&task->vma_lock);
 
-	int ret = 0;
 	vma_t* last = NULL;
 	vma_t* parent = parent_task->vma_list;
 
 	while (parent) {
 		vma_t *new = kmalloc(sizeof(vma_t));
 		if (BUILTIN_EXPECT(!new, 0)) {
-			ret = -ENOMEM;
+			spinlock_unlock(&task->vma_lock);
-			goto out;
+			spinlock_unlock(&parent_task->vma_lock);
+			return -ENOMEM;
 		}
 
 		new->start = parent->start;
@@ -292,20 +286,22 @@ int copy_vma_list(task_t* task)
 		parent = parent->next;
 	}
 
-out:
+	return 0;
-	spinlock_unlock(&task->vma_lock);
-	spinlock_unlock(&parent_task->vma_lock);
-	return ret;
 }
 
 int drop_vma_list()
 {
 	task_t* task = per_core(current_task);
+	vma_t* vma;
+
+	kprintf("drop_vma_list: task = %u\n", task->id); // TODO: remove
 
 	spinlock_lock(&task->vma_lock);
 
-	while(task->vma_list)
+	while (vma = task->vma_list) {
-		pfree((void*) task->vma_list->start, task->vma_list->end - task->vma_list->start);
+		task->vma_list = vma->next;
+		kfree(vma);
+	}
 
 	spinlock_unlock(&task->vma_lock);
 
@@ -320,7 +316,7 @@ void vma_dump()
 				(vma->flags & VMA_READ) ? 'r' : '-',
 				(vma->flags & VMA_WRITE) ? 'w' : '-',
 				(vma->flags & VMA_EXECUTE) ? 'x' : '-');
-			vma = vma->prev;
+			vma = vma->next;
 		}
 	}