prev_end = vma->size + (unsigned long) vma->addr;
prev_end = vma->size + addr;
void get_vmalloc_info(struct vmalloc_info *vmi){	struct vm_struct *vma;	unsigned long free_area_size;	unsigned long prev_end;	vmi->used = 0;	if (!vmlist) {		vmi->largest_chunk = VMALLOC_TOTAL;	}	else {		vmi->largest_chunk = 0;		prev_end = VMALLOC_START;		read_lock(&vmlist_lock);		for (vma = vmlist; vma; vma = vma->next) {			vmi->used += vma->size;			free_area_size = (unsigned long) vma->addr - prev_end;			if (vmi->largest_chunk < free_area_size)				vmi->largest_chunk = free_area_size;			prev_end = vma->size + (unsigned long) vma->addr;		}		if (VMALLOC_END - prev_end > vmi->largest_chunk)			vmi->largest_chunk = VMALLOC_END - prev_end;		read_unlock(&vmlist_lock);	}}