  The entailment problem $\varphi \models \psi$ in Separation Logic
\cite{IshtiaqOHearn01,Reynolds02}, between separated conjunctions of equational
($x \iseq y$ and $x \not\iseq y$), spatial ($x \mapsto (y_1,\ldots,y_\rank)$)
and predicate ($p(x_1,\ldots,x_n)$) atoms, interpreted by a finite set of
inductive rules, is undecidable in general. Certain restrictions on the set of
inductive definitions lead to decidable classes of entailment problems.
Currently, there are two such decidable classes, based on two restrictions,
called \emph{establishment}
\cite{IosifRogalewiczSimacek13,KatelaanMathejaZuleger19,PZ20} and
\emph{restrictedness} \cite{EIP21a}, respectively. Both classes are shown to be
in \twoexptime\ by the independent proofs from \cite{PZ20} and \cite{EIP21a},
respectively, and a many-one reduction of established to restricted entailment
problems has been given \cite{EIP21a}. In this paper, we strictly generalize
the restricted class, by distinguishing the conditions that apply only to the
left- ($\varphi$) and the right- ($\psi$) hand side of entailments,
respectively. We provide a many-one reduction of this generalized class, called
\emph{safe}, to the established class. Together with the reduction of
established to restricted entailment problems, this new reduction closes the
loop and shows that the three classes of entailment problems (respectively
established, restricted and safe) form a single, unified, \twoexptime-complete
class.
