vdpa: Make use of PFN_PHYS/PFN_UP/PFN_DOWN helper macro

it's a nice refactor to make use of
PFN_PHYS/PFN_UP/PFN_DOWN helper macro

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20210802013717.851-1-caihuoqing@baidu.com
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/vhost/vdpa.c

@@ -507,15 +507,15 @@ static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
 	unsigned long pfn, pinned;
 
 	while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
-		pinned = map->size >> PAGE_SHIFT;
-		for (pfn = map->addr >> PAGE_SHIFT;
+		pinned = PFN_DOWN(map->size);
+		for (pfn = PFN_DOWN(map->addr);
 		     pinned > 0; pfn++, pinned--) {
 			page = pfn_to_page(pfn);
 			if (map->perm & VHOST_ACCESS_WO)
 				set_page_dirty_lock(page);
 			unpin_user_page(page);
 		}
-		atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
+		atomic64_sub(PFN_DOWN(map->size), &dev->mm->pinned_vm);
 		vhost_iotlb_map_free(iotlb, map);
 	}
 }
@@ -577,7 +577,7 @@ static int vhost_vdpa_map(struct vhost_vdpa *v,
 	if (r)
 		vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1);
 	else
-		atomic64_add(size >> PAGE_SHIFT, &dev->mm->pinned_vm);
+		atomic64_add(PFN_DOWN(size), &dev->mm->pinned_vm);
 
 	return r;
 }
@@ -631,15 +631,15 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
 	if (msg->perm & VHOST_ACCESS_WO)
 		gup_flags |= FOLL_WRITE;
 
-	npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
+	npages = PFN_UP(msg->size + (iova & ~PAGE_MASK));
 	if (!npages) {
 		ret = -EINVAL;
 		goto free;
 	}
 
 	mmap_read_lock(dev->mm);
 
-	lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+	lock_limit = PFN_DOWN(rlimit(RLIMIT_MEMLOCK));
 	if (npages + atomic64_read(&dev->mm->pinned_vm) > lock_limit) {
 		ret = -ENOMEM;
 		goto unlock;
@@ -673,9 +673,9 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
 
 			if (last_pfn && (this_pfn != last_pfn + 1)) {
 				/* Pin a contiguous chunk of memory */
-				csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
+				csize = PFN_PHYS(last_pfn - map_pfn + 1);
 				ret = vhost_vdpa_map(v, iova, csize,
-						     map_pfn << PAGE_SHIFT,
+						     PFN_PHYS(map_pfn),
 						     msg->perm);
 				if (ret) {
 					/*
@@ -699,13 +699,13 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
 			last_pfn = this_pfn;
 		}
 
-		cur_base += pinned << PAGE_SHIFT;
+		cur_base += PFN_PHYS(pinned);
 		npages -= pinned;
 	}
 
 	/* Pin the rest chunk */
-	ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
-			     map_pfn << PAGE_SHIFT, msg->perm);
+	ret = vhost_vdpa_map(v, iova, PFN_PHYS(last_pfn - map_pfn + 1),
+			     PFN_PHYS(map_pfn), msg->perm);
 out:
 	if (ret) {
 		if (nchunks) {
@@ -945,7 +945,7 @@ static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf)
 
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 	if (remap_pfn_range(vma, vmf->address & PAGE_MASK,
-			    notify.addr >> PAGE_SHIFT, PAGE_SIZE,
+			    PFN_DOWN(notify.addr), PAGE_SIZE,
 			    vma->vm_page_prot))
 		return VM_FAULT_SIGBUS;