[RFC PATCH v2.1 22/30] Documentation/x86: Introduce enclave runtime management section

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>,
	Jonathan Corbet <corbet@lwn.net>,
	linux-kernel@vger.kernel.org (open list:X86 ARCHITECTURE (32-BIT
	AND 64-BIT)), linux-doc@vger.kernel.org (open list:DOCUMENTATION)
Subject: [RFC PATCH v2.1 22/30] Documentation/x86: Introduce enclave runtime management section
Date: Fri,  4 Mar 2022 11:35:16 +0200	[thread overview]
Message-ID: <20220304093524.397485-22-jarkko@kernel.org> (raw)
In-Reply-To: <20220304093524.397485-1-jarkko@kernel.org>

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

Enclave runtime management is introduced following the pattern
of the section describing enclave building. Provide a brief
summary of enclave runtime management, pointing to the functions
implementing the ioctl()s that will contain details within their
kernel-doc.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
---
 Documentation/x86/sgx.rst | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Documentation/x86/sgx.rst b/Documentation/x86/sgx.rst
index 5659932728a5..6c66ce0ec69c 100644
--- a/Documentation/x86/sgx.rst
+++ b/Documentation/x86/sgx.rst
@@ -128,6 +128,22 @@ pages and establish enclave page permissions.
                sgx_ioc_enclave_init
                sgx_ioc_enclave_provision
 
+Enclave runtime management
+--------------------------
+
+Systems supporting SGX2 additionally support changes to initialized
+enclaves: modifying enclave page permissions and type, and dynamically
+adding and removing of enclave pages. When an enclave accesses an address
+within its address range that does not have a backing page then a new
+regular page will be dynamically added to the enclave. The enclave is
+still required to run EACCEPT on the new page before it can be used.
+
+.. kernel-doc:: arch/x86/kernel/cpu/sgx/ioctl.c
+   :functions: sgx_ioc_enclave_relax_perm
+               sgx_ioc_enclave_restrict_perm
+               sgx_ioc_enclave_modt
+               sgx_ioc_enclave_remove_pages
+
 Enclave vDSO
 ------------
 
-- 
2.35.1

