[RFC PATCH v2.1 04/30] x86/sgx: Add wrapper for SGX2 EAUG function

From: Jarkko Sakkinen <jarkko@kernel.org>
To: linux-sgx@vger.kernel.org
Cc: Nathaniel McCallum <nathaniel@profian.com>,
	Reinette Chatre <reinette.chatre@intel.com>,
	Jarkko Sakkinen <jarkko@kernel.org>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
	"H. Peter Anvin" <hpa@zytor.com>,
	linux-kernel@vger.kernel.org (open list:X86 ARCHITECTURE (32-BIT
	AND 64-BIT))
Subject: [RFC PATCH v2.1 04/30] x86/sgx: Add wrapper for SGX2 EAUG function
Date: Fri,  4 Mar 2022 11:34:58 +0200	[thread overview]
Message-ID: <20220304093524.397485-4-jarkko@kernel.org> (raw)
In-Reply-To: <20220304093524.397485-1-jarkko@kernel.org>

From: Reinette Chatre <reinette.chatre@intel.com>

Add a wrapper for the EAUG ENCLS leaf function used to
add a page to an initialized enclave.

EAUG:
1) Stores all properties of the new enclave page in the SGX
   hardware's Enclave Page Cache Map (EPCM).
2) Sets the PENDING bit in the EPCM entry of the enclave page.
   This bit is cleared by the enclave by invoking ENCLU leaf
   function EACCEPT or EACCEPTCOPY.

Access from within the enclave to the new enclave page is not
possible until the PENDING bit is cleared.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
---
 arch/x86/kernel/cpu/sgx/encls.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/kernel/cpu/sgx/encls.h b/arch/x86/kernel/cpu/sgx/encls.h
index 7a1ecf704ec1..99004b02e2ed 100644
--- a/arch/x86/kernel/cpu/sgx/encls.h
+++ b/arch/x86/kernel/cpu/sgx/encls.h
@@ -227,4 +227,10 @@ static inline int __emodt(struct sgx_secinfo *secinfo, void *addr)
 	return __encls_ret_2(EMODT, secinfo, addr);
 }
 
+/* Zero a page of EPC memory and add it to an initialized enclave. */
+static inline int __eaug(struct sgx_pageinfo *pginfo, void *addr)
+{
+	return __encls_2(EAUG, pginfo, addr);
+}
+
 #endif /* _X86_ENCLS_H */
-- 
2.35.1

