NFS: Ensure we revalidate the inode correctly after remove or rename

We may need to revalidate the change attribute, ctime and the nlinks count.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/dir.c

@@ -1284,11 +1284,13 @@ static void nfs_drop_nlink(struct inode *inode)
 {
 	spin_lock(&inode->i_lock);
 	/* drop the inode if we're reasonably sure this is the last link */
-	if (inode->i_nlink == 1)
-		clear_nlink(inode);
+	if (inode->i_nlink > 0)
+		drop_nlink(inode);
+	NFS_I(inode)->attr_gencount = nfs_inc_attr_generation_counter();
 	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_CHANGE
 		| NFS_INO_INVALID_CTIME
-		| NFS_INO_INVALID_OTHER;
+		| NFS_INO_INVALID_OTHER
+		| NFS_INO_REVAL_FORCED;
 	spin_unlock(&inode->i_lock);
 }
 
@@ -2050,7 +2052,15 @@ int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	} else
 		error = task->tk_status;
 	rpc_put_task(task);
-	nfs_mark_for_revalidate(old_inode);
+	/* Ensure the inode attributes are revalidated */
+	if (error == 0) {
+		spin_lock(&old_inode->i_lock);
+		NFS_I(old_inode)->attr_gencount = nfs_inc_attr_generation_counter();
+		NFS_I(old_inode)->cache_validity |= NFS_INO_INVALID_CHANGE
+			| NFS_INO_INVALID_CTIME
+			| NFS_INO_REVAL_FORCED;
+		spin_unlock(&old_inode->i_lock);
+	}
 out:
 	if (rehash)
 		d_rehash(rehash);