9p: don't opencode filemap_fdatawrite_range in v9fs_mmap_vm_close

Use filemap_fdatawrite_range instead of opencoding the logic using
filemap_fdatawrite_wbc.

Signed-off-by: Christoph Hellwig <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Reviewed-by: Jan Kara <[e-mail]>
Reviewed-by: Damien Le Moal <[e-mail]>
Reviewed-by: Johannes Thumshirn <[e-mail]>
Signed-off-by: Christian Brauner <[e-mail]>

fs/9p/vfs_file.c

···
 
 static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
 {
-	struct inode *inode;
-
-	struct writeback_control wbc = {
-		.nr_to_write = LONG_MAX,
-		.sync_mode = WB_SYNC_ALL,
-		.range_start = (loff_t)vma->vm_pgoff * PAGE_SIZE,
-		 /* absolute end, byte at end included */
-		.range_end = (loff_t)vma->vm_pgoff * PAGE_SIZE +
-			(vma->vm_end - vma->vm_start - 1),
-	};
-
 	if (!(vma->vm_flags & VM_SHARED))
 		return;
 
 	p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
 
-	inode = file_inode(vma->vm_file);
-	filemap_fdatawrite_wbc(inode->i_mapping, &wbc);
+	filemap_fdatawrite_range(file_inode(vma->vm_file)->i_mapping,
+			(loff_t)vma->vm_pgoff * PAGE_SIZE,
+			(loff_t)vma->vm_pgoff * PAGE_SIZE +
+				(vma->vm_end - vma->vm_start - 1));
 }
 
 static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {