mm: use vm_unmapped_area() on frv architecture

Update the frv arch_get_unmapped_area function to make use of
vm_unmapped_area() instead of implementing a brute force search.
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/frv/mm/elf-fdpic.c

@@ -60,7 +60,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 				     unsigned long pgoff, unsigned long flags)
 {
 	struct vm_area_struct *vma;
-	unsigned long limit;
+	struct vm_unmapped_area_info info;
 
 	if (len > TASK_SIZE)
 		return -ENOMEM;
@@ -79,39 +79,24 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	}
 
 	/* search between the bottom of user VM and the stack grow area */
-	addr = PAGE_SIZE;
-	limit = (current->mm->start_stack - 0x00200000);
-	if (addr + len <= limit) {
-		limit -= len;
-
-		if (addr <= limit) {
-			vma = find_vma(current->mm, PAGE_SIZE);
-			for (; vma; vma = vma->vm_next) {
-				if (addr > limit)
-					break;
-				if (addr + len <= vma->vm_start)
+	info.flags = 0;
+	info.length = len;
+	info.low_limit = PAGE_SIZE;
+	info.high_limit = (current->mm->start_stack - 0x00200000);
+	info.align_mask = 0;
+	info.align_offset = 0;
+	addr = vm_unmapped_area(&info);
+	if (!(addr & ~PAGE_MASK))
 		goto success;
-				addr = vma->vm_end;
-			}
-		}
-	}
+	VM_BUG_ON(addr != -ENOMEM);
 
 	/* search from just above the WorkRAM area to the top of memory */
-	addr = PAGE_ALIGN(0x80000000);
-	limit = TASK_SIZE - len;
-	if (addr <= limit) {
-		vma = find_vma(current->mm, addr);
-		for (; vma; vma = vma->vm_next) {
-			if (addr > limit)
-				break;
-			if (addr + len <= vma->vm_start)
+	info.low_limit = PAGE_ALIGN(0x80000000);
+	info.high_limit = TASK_SIZE;
+	addr = vm_unmapped_area(&info);
+	if (!(addr & ~PAGE_MASK))
 		goto success;
-			addr = vma->vm_end;
-		}
-
-		if (!vma && addr <= limit)
-			goto success;
-	}
+	VM_BUG_ON(addr != -ENOMEM);
 
 #if 0
 	printk("[area] l=%lx (ENOMEM) f='%s'\n",