[v19,RESEND,16/27] x86/sgx: Add the Linux SGX Enclave Driver
diff mbox series

Message ID 20190320162119.4469-17-jarkko.sakkinen@linux.intel.com
State New
Headers show
Series
  • Intel SGX1 support
Related show

Commit Message

Jarkko Sakkinen March 20, 2019, 4:21 p.m. UTC
Intel Software Guard eXtensions (SGX) is a set of CPU instructions that
can be used by applications to set aside private regions of code and
data. The code outside the enclave is disallowed to access the memory
inside the enclave by the CPU access control.

This commit adds the Linux SGX Enclave Driver that provides an ioctl API
to manage enclaves. The address range for an enclave, commonly referred
as ELRANGE in the documentation (e.g. Intel SDM), is reserved with
mmap() against /dev/sgx. After that a set ioctls is used to build
the enclave to the ELRANGE.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Co-developed-by: Serge Ayoun <serge.ayoun@intel.com>
Signed-off-by: Serge Ayoun <serge.ayoun@intel.com>
Co-developed-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
Signed-off-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
Co-developed-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
---
 Documentation/ioctl/ioctl-number.txt    |   1 +
 arch/x86/Kconfig                        |  17 +-
 arch/x86/include/uapi/asm/sgx.h         |  59 ++
 arch/x86/kernel/cpu/sgx/Makefile        |   5 +-
 arch/x86/kernel/cpu/sgx/driver/Makefile |   3 +
 arch/x86/kernel/cpu/sgx/driver/driver.h |  38 ++
 arch/x86/kernel/cpu/sgx/driver/ioctl.c  | 795 ++++++++++++++++++++++++
 arch/x86/kernel/cpu/sgx/driver/main.c   | 290 +++++++++
 arch/x86/kernel/cpu/sgx/encl.c          | 358 +++++++++++
 arch/x86/kernel/cpu/sgx/encl.h          |  88 +++
 arch/x86/kernel/cpu/sgx/encls.c         |   1 +
 arch/x86/kernel/cpu/sgx/main.c          |   3 +
 arch/x86/kernel/cpu/sgx/sgx.h           |   1 +
 13 files changed, 1657 insertions(+), 2 deletions(-)
 create mode 100644 arch/x86/include/uapi/asm/sgx.h
 create mode 100644 arch/x86/kernel/cpu/sgx/driver/Makefile
 create mode 100644 arch/x86/kernel/cpu/sgx/driver/driver.h
 create mode 100644 arch/x86/kernel/cpu/sgx/driver/ioctl.c
 create mode 100644 arch/x86/kernel/cpu/sgx/driver/main.c
 create mode 100644 arch/x86/kernel/cpu/sgx/encl.c
 create mode 100644 arch/x86/kernel/cpu/sgx/encl.h

Comments

Huang, Kai March 26, 2019, 12:01 p.m. UTC | #1
On Wed, 2019-03-20 at 18:21 +0200, Jarkko Sakkinen wrote:
> Intel Software Guard eXtensions (SGX) is a set of CPU instructions that
> can be used by applications to set aside private regions of code and
> data. The code outside the enclave is disallowed to access the memory
> inside the enclave by the CPU access control.
> 
> This commit adds the Linux SGX Enclave Driver that provides an ioctl API
> to manage enclaves. The address range for an enclave, commonly referred
> as ELRANGE in the documentation (e.g. Intel SDM), is reserved with
> mmap() against /dev/sgx. After that a set ioctls is used to build
> the enclave to the ELRANGE.
> 
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> Co-developed-by: Serge Ayoun <serge.ayoun@intel.com>
> Signed-off-by: Serge Ayoun <serge.ayoun@intel.com>
> Co-developed-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
> Signed-off-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
> Co-developed-by: Suresh Siddha <suresh.b.siddha@intel.com>
> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
> ---
>  Documentation/ioctl/ioctl-number.txt    |   1 +
>  arch/x86/Kconfig                        |  17 +-
>  arch/x86/include/uapi/asm/sgx.h         |  59 ++
>  arch/x86/kernel/cpu/sgx/Makefile        |   5 +-
>  arch/x86/kernel/cpu/sgx/driver/Makefile |   3 +
>  arch/x86/kernel/cpu/sgx/driver/driver.h |  38 ++
>  arch/x86/kernel/cpu/sgx/driver/ioctl.c  | 795 ++++++++++++++++++++++++
>  arch/x86/kernel/cpu/sgx/driver/main.c   | 290 +++++++++
>  arch/x86/kernel/cpu/sgx/encl.c          | 358 +++++++++++
>  arch/x86/kernel/cpu/sgx/encl.h          |  88 +++
>  arch/x86/kernel/cpu/sgx/encls.c         |   1 +
>  arch/x86/kernel/cpu/sgx/main.c          |   3 +
>  arch/x86/kernel/cpu/sgx/sgx.h           |   1 +
>  13 files changed, 1657 insertions(+), 2 deletions(-)
>  create mode 100644 arch/x86/include/uapi/asm/sgx.h
>  create mode 100644 arch/x86/kernel/cpu/sgx/driver/Makefile
>  create mode 100644 arch/x86/kernel/cpu/sgx/driver/driver.h
>  create mode 100644 arch/x86/kernel/cpu/sgx/driver/ioctl.c
>  create mode 100644 arch/x86/kernel/cpu/sgx/driver/main.c
>  create mode 100644 arch/x86/kernel/cpu/sgx/encl.c
>  create mode 100644 arch/x86/kernel/cpu/sgx/encl.h

Shouldn't the driver be located somewhere under drivers/, but not under arch/x86?

I don't think x86 maintainers should have the burden to review every code change made to SGX driver?

Thanks,
-Kai
Thomas Gleixner March 26, 2019, 12:40 p.m. UTC | #2
On Tue, 26 Mar 2019, Huang, Kai wrote:
> On Wed, 2019-03-20 at 18:21 +0200, Jarkko Sakkinen wrote:
> >  13 files changed, 1657 insertions(+), 2 deletions(-)
> >  create mode 100644 arch/x86/include/uapi/asm/sgx.h
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/Makefile
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/driver.h
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/ioctl.c
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/main.c
> >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.c
> >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.h
> 
> Shouldn't the driver be located somewhere under drivers/, but not under arch/x86?
> 
> I don't think x86 maintainers should have the burden to review every code
> change made to SGX driver?

I rather prefer to have it in x86. Why? Because driver code has a tendency
to get under the radar.

Thanks,

	tglx
Sean Christopherson March 26, 2019, 2:54 p.m. UTC | #3
On Tue, Mar 26, 2019 at 01:40:57PM +0100, Thomas Gleixner wrote:
> On Tue, 26 Mar 2019, Huang, Kai wrote:
> > On Wed, 2019-03-20 at 18:21 +0200, Jarkko Sakkinen wrote:
> > >  13 files changed, 1657 insertions(+), 2 deletions(-)
> > >  create mode 100644 arch/x86/include/uapi/asm/sgx.h
> > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/Makefile
> > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/driver.h
> > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/ioctl.c
> > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/main.c
> > >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.c
> > >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.h
> > 
> > Shouldn't the driver be located somewhere under drivers/, but not under arch/x86?
> > 
> > I don't think x86 maintainers should have the burden to review every code
> > change made to SGX driver?
> 
> I rather prefer to have it in x86. Why? Because driver code has a tendency
> to get under the radar.

And having everything under arch/x86 will likely reduce the maintenance
burden for everyone:

   - Doesn't require taking changes through multiple trees or coordinating
     acks from multiple maintainers.

   - Significantly reduces the number of functions, macros, structs and
     variables that needs to be exposed in asm/sgx.h (actually eliminates
     it entirely at this point) which allows for sane code organization as
     opposed to dumping everything in one big header.

   - Mostly avoids bikeshedding over whether something is architectural
     or belongs in the so called driver.
Huang, Kai March 26, 2019, 9:11 p.m. UTC | #4
> On Tue, Mar 26, 2019 at 01:40:57PM +0100, Thomas Gleixner wrote:
> > On Tue, 26 Mar 2019, Huang, Kai wrote:
> > > On Wed, 2019-03-20 at 18:21 +0200, Jarkko Sakkinen wrote:
> > > >  13 files changed, 1657 insertions(+), 2 deletions(-)  create mode
> > > > 100644 arch/x86/include/uapi/asm/sgx.h  create mode 100644
> > > > arch/x86/kernel/cpu/sgx/driver/Makefile
> > > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/driver.h
> > > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/ioctl.c
> > > >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/main.c
> > > >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.c  create mode
> > > > 100644 arch/x86/kernel/cpu/sgx/encl.h
> > >
> > > Shouldn't the driver be located somewhere under drivers/, but not under
> arch/x86?
> > >
> > > I don't think x86 maintainers should have the burden to review every
> > > code change made to SGX driver?
> >
> > I rather prefer to have it in x86. Why? Because driver code has a
> > tendency to get under the radar.
> 
> And having everything under arch/x86 will likely reduce the maintenance
> burden for everyone:
> 
>    - Doesn't require taking changes through multiple trees or coordinating
>      acks from multiple maintainers.
> 
>    - Significantly reduces the number of functions, macros, structs and
>      variables that needs to be exposed in asm/sgx.h (actually eliminates
>      it entirely at this point) which allows for sane code organization as
>      opposed to dumping everything in one big header.
> 
>    - Mostly avoids bikeshedding over whether something is architectural
>      or belongs in the so called driver.

Sure. Thanks.

Thanks,
-Kai
Jarkko Sakkinen March 27, 2019, 5:02 a.m. UTC | #5
On Tue, Mar 26, 2019 at 12:01:31PM +0000, Huang, Kai wrote:
> On Wed, 2019-03-20 at 18:21 +0200, Jarkko Sakkinen wrote:
> > Intel Software Guard eXtensions (SGX) is a set of CPU instructions that
> > can be used by applications to set aside private regions of code and
> > data. The code outside the enclave is disallowed to access the memory
> > inside the enclave by the CPU access control.
> > 
> > This commit adds the Linux SGX Enclave Driver that provides an ioctl API
> > to manage enclaves. The address range for an enclave, commonly referred
> > as ELRANGE in the documentation (e.g. Intel SDM), is reserved with
> > mmap() against /dev/sgx. After that a set ioctls is used to build
> > the enclave to the ELRANGE.
> > 
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> > Co-developed-by: Serge Ayoun <serge.ayoun@intel.com>
> > Signed-off-by: Serge Ayoun <serge.ayoun@intel.com>
> > Co-developed-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
> > Signed-off-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
> > Co-developed-by: Suresh Siddha <suresh.b.siddha@intel.com>
> > Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
> > ---
> >  Documentation/ioctl/ioctl-number.txt    |   1 +
> >  arch/x86/Kconfig                        |  17 +-
> >  arch/x86/include/uapi/asm/sgx.h         |  59 ++
> >  arch/x86/kernel/cpu/sgx/Makefile        |   5 +-
> >  arch/x86/kernel/cpu/sgx/driver/Makefile |   3 +
> >  arch/x86/kernel/cpu/sgx/driver/driver.h |  38 ++
> >  arch/x86/kernel/cpu/sgx/driver/ioctl.c  | 795 ++++++++++++++++++++++++
> >  arch/x86/kernel/cpu/sgx/driver/main.c   | 290 +++++++++
> >  arch/x86/kernel/cpu/sgx/encl.c          | 358 +++++++++++
> >  arch/x86/kernel/cpu/sgx/encl.h          |  88 +++
> >  arch/x86/kernel/cpu/sgx/encls.c         |   1 +
> >  arch/x86/kernel/cpu/sgx/main.c          |   3 +
> >  arch/x86/kernel/cpu/sgx/sgx.h           |   1 +
> >  13 files changed, 1657 insertions(+), 2 deletions(-)
> >  create mode 100644 arch/x86/include/uapi/asm/sgx.h
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/Makefile
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/driver.h
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/ioctl.c
> >  create mode 100644 arch/x86/kernel/cpu/sgx/driver/main.c
> >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.c
> >  create mode 100644 arch/x86/kernel/cpu/sgx/encl.h
> 
> Shouldn't the driver be located somewhere under drivers/, but not under arch/x86?
> 
> I don't think x86 maintainers should have the burden to review every code change made to SGX driver?

Not sure I got your angle. It is x86 tied code.

$ git grep tristate arch/x86/ | wc -l
22

/Jarkko

Patch
diff mbox series

diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index c9558146ac58..ef2694221cd0 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -312,6 +312,7 @@  Code  Seq#(hex)	Include File		Comments
 					<mailto:tlewis@mindspring.com>
 0xA3	90-9F	linux/dtlk.h
 0xA4	00-1F	uapi/linux/tee.h	Generic TEE subsystem
+0xA4	00-02	uapi/asm/sgx.h		conflict!
 0xAA	00-3F	linux/uapi/linux/userfaultfd.h
 0xAB	00-1F	linux/nbd.h
 0xAC	00-1F	linux/raw.h
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index dc630208003f..34257b5659cc 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1925,7 +1925,6 @@  config INTEL_SGX
 	bool "Intel SGX core functionality"
 	depends on X86_64 && CPU_SUP_INTEL
 	help
-
 	Intel(R) SGX is a set of CPU instructions that can be used by
 	applications to set aside private regions of code and data.  The code
 	outside the enclave is disallowed to access the memory inside the
@@ -1940,6 +1939,22 @@  config INTEL_SGX
 
 	If unsure, say N.
 
+config INTEL_SGX_DRIVER
+	tristate "Intel(R) SGX Driver"
+	default n
+	depends on X86_64 && CPU_SUP_INTEL && INTEL_SGX
+	select MMU_NOTIFIER
+	select CRYPTO
+	select CRYPTO_SHA256
+	help
+	This options enables the kernel SGX driver that allows to construct
+	enclaves to the process memory by using a device node (by default
+	/dev/sgx) and a set of ioctls. The driver requires that the MSRs
+	specifying the public key hash for the launch enclave are writable so
+	that Linux has the full control to run enclaves.
+
+	For details, see Documentation/x86/intel_sgx.rst
+
 config EFI
 	bool "EFI runtime service support"
 	depends on ACPI
diff --git a/arch/x86/include/uapi/asm/sgx.h b/arch/x86/include/uapi/asm/sgx.h
new file mode 100644
index 000000000000..aadf9c76e360
--- /dev/null
+++ b/arch/x86/include/uapi/asm/sgx.h
@@ -0,0 +1,59 @@ 
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
+/**
+ * Copyright(c) 2016-18 Intel Corporation.
+ */
+#ifndef _UAPI_ASM_X86_SGX_H
+#define _UAPI_ASM_X86_SGX_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+#define SGX_MAGIC 0xA4
+
+#define SGX_IOC_ENCLAVE_CREATE \
+	_IOW(SGX_MAGIC, 0x00, struct sgx_enclave_create)
+#define SGX_IOC_ENCLAVE_ADD_PAGE \
+	_IOW(SGX_MAGIC, 0x01, struct sgx_enclave_add_page)
+#define SGX_IOC_ENCLAVE_INIT \
+	_IOW(SGX_MAGIC, 0x02, struct sgx_enclave_init)
+
+/* IOCTL return values */
+#define SGX_POWER_LOST_ENCLAVE		0x40000000
+
+/**
+ * struct sgx_enclave_create - parameter structure for the
+ *                             %SGX_IOC_ENCLAVE_CREATE ioctl
+ * @src:	address for the SECS page data
+ */
+struct sgx_enclave_create  {
+	__u64	src;
+};
+
+/**
+ * struct sgx_enclave_add_page - parameter structure for the
+ *                               %SGX_IOC_ENCLAVE_ADD_PAGE ioctl
+ * @addr:	address within the ELRANGE
+ * @src:	address for the page data
+ * @secinfo:	address for the SECINFO data
+ * @mrmask:	bitmask for the measured 256 byte chunks
+ */
+struct sgx_enclave_add_page {
+	__u64	addr;
+	__u64	src;
+	__u64	secinfo;
+	__u16	mrmask;
+} __attribute__((__packed__));
+
+
+/**
+ * struct sgx_enclave_init - parameter structure for the
+ *                           %SGX_IOC_ENCLAVE_INIT ioctl
+ * @addr:	address within the ELRANGE
+ * @sigstruct:	address for the SIGSTRUCT data
+ */
+struct sgx_enclave_init {
+	__u64	addr;
+	__u64	sigstruct;
+};
+
+#endif /* _UAPI_ASM_X86_SGX_H */
diff --git a/arch/x86/kernel/cpu/sgx/Makefile b/arch/x86/kernel/cpu/sgx/Makefile
index 20ce33655ff4..48174e5fc181 100644
--- a/arch/x86/kernel/cpu/sgx/Makefile
+++ b/arch/x86/kernel/cpu/sgx/Makefile
@@ -1 +1,4 @@ 
-obj-y += main.o encls.o
+obj-y += encl.o
+obj-y += encls.o
+obj-y += main.o
+obj-$(CONFIG_INTEL_SGX_DRIVER) += driver/
diff --git a/arch/x86/kernel/cpu/sgx/driver/Makefile b/arch/x86/kernel/cpu/sgx/driver/Makefile
new file mode 100644
index 000000000000..01ebbbb06a47
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/driver/Makefile
@@ -0,0 +1,3 @@ 
+obj-$(CONFIG_INTEL_SGX_DRIVER) += sgx.o
+sgx-$(CONFIG_INTEL_SGX_DRIVER) += ioctl.o
+sgx-$(CONFIG_INTEL_SGX_DRIVER) += main.o
diff --git a/arch/x86/kernel/cpu/sgx/driver/driver.h b/arch/x86/kernel/cpu/sgx/driver/driver.h
new file mode 100644
index 000000000000..b736411b5317
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/driver/driver.h
@@ -0,0 +1,38 @@ 
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
+/**
+ * Copyright(c) 2016-19 Intel Corporation.
+ */
+#ifndef __ARCH_INTEL_SGX_H__
+#define __ARCH_INTEL_SGX_H__
+
+#include <crypto/hash.h>
+#include <linux/kref.h>
+#include <linux/mmu_notifier.h>
+#include <linux/radix-tree.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/workqueue.h>
+#include <uapi/asm/sgx.h>
+#include "../arch.h"
+#include "../encl.h"
+#include "../encls.h"
+#include "../sgx.h"
+
+#define SGX_DRV_NR_DEVICES	1
+#define SGX_EINIT_SPIN_COUNT	20
+#define SGX_EINIT_SLEEP_COUNT	50
+#define SGX_EINIT_SLEEP_TIME	20
+
+extern struct workqueue_struct *sgx_encl_wq;
+extern u64 sgx_encl_size_max_32;
+extern u64 sgx_encl_size_max_64;
+extern u32 sgx_misc_reserved_mask;
+extern u64 sgx_attributes_reserved_mask;
+extern u64 sgx_xfrm_reserved_mask;
+extern u32 sgx_xsave_size_tbl[64];
+
+extern const struct file_operations sgx_fs_provision_fops;
+
+long sgx_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
+
+#endif /* __ARCH_X86_INTEL_SGX_H__ */
diff --git a/arch/x86/kernel/cpu/sgx/driver/ioctl.c b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
new file mode 100644
index 000000000000..4b9a91b53b50
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
@@ -0,0 +1,795 @@ 
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2016-19 Intel Corporation.
+
+#include <asm/mman.h>
+#include <linux/delay.h>
+#include <linux/file.h>
+#include <linux/hashtable.h>
+#include <linux/highmem.h>
+#include <linux/ratelimit.h>
+#include <linux/sched/signal.h>
+#include <linux/shmem_fs.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include "driver.h"
+
+struct sgx_add_page_req {
+	struct sgx_encl *encl;
+	struct sgx_encl_page *encl_page;
+	struct sgx_secinfo secinfo;
+	unsigned long mrmask;
+	struct list_head list;
+};
+
+static int sgx_encl_get(unsigned long addr, struct sgx_encl **encl)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	int ret;
+
+	if (addr & (PAGE_SIZE - 1))
+		return -EINVAL;
+
+	down_read(&mm->mmap_sem);
+
+	ret = sgx_encl_find(mm, addr, &vma);
+	if (!ret) {
+		*encl = vma->vm_private_data;
+
+		if ((*encl)->flags & SGX_ENCL_SUSPEND)
+			ret = SGX_POWER_LOST_ENCLAVE;
+		else
+			kref_get(&(*encl)->refcount);
+	}
+
+	up_read(&mm->mmap_sem);
+	return ret;
+}
+
+static bool sgx_process_add_page_req(struct sgx_add_page_req *req,
+				     struct sgx_epc_page *epc_page)
+{
+	struct sgx_encl_page *encl_page = req->encl_page;
+	struct sgx_encl *encl = req->encl;
+	unsigned long page_index = sgx_encl_get_index(encl, encl_page);
+	struct sgx_secinfo secinfo;
+	struct sgx_pageinfo pginfo;
+	struct page *backing;
+	unsigned long addr;
+	int ret;
+	int i;
+
+	if (encl->flags & (SGX_ENCL_SUSPEND | SGX_ENCL_DEAD))
+		return false;
+
+	addr = SGX_ENCL_PAGE_ADDR(encl_page);
+
+	backing = sgx_encl_get_backing_page(encl, page_index);
+	if (IS_ERR(backing))
+		return false;
+
+	/*
+	 * The SECINFO field must be 64-byte aligned, copy it to a local
+	 * variable that is guaranteed to be aligned as req->secinfo may
+	 * or may not be 64-byte aligned, e.g. req may have been allocated
+	 * via kzalloc which is not aware of __aligned attributes.
+	 */
+	memcpy(&secinfo, &req->secinfo, sizeof(secinfo));
+
+	pginfo.secs = (unsigned long)sgx_epc_addr(encl->secs.epc_page);
+	pginfo.addr = addr;
+	pginfo.metadata = (unsigned long)&secinfo;
+	pginfo.contents = (unsigned long)kmap_atomic(backing);
+	ret = __eadd(&pginfo, sgx_epc_addr(epc_page));
+	kunmap_atomic((void *)(unsigned long)pginfo.contents);
+
+	put_page(backing);
+
+	if (ret) {
+		if (encls_failed(ret))
+			ENCLS_WARN(ret, "EADD");
+		return false;
+	}
+
+	for_each_set_bit(i, &req->mrmask, 16) {
+		ret = __eextend(sgx_epc_addr(encl->secs.epc_page),
+				sgx_epc_addr(epc_page) + (i * 0x100));
+		if (ret) {
+			if (encls_failed(ret))
+				ENCLS_WARN(ret, "EEXTEND");
+			return false;
+		}
+	}
+
+	encl_page->encl = encl;
+	encl_page->epc_page = epc_page;
+	encl->secs_child_cnt++;
+
+	return true;
+}
+
+static void sgx_add_page_worker(struct work_struct *work)
+{
+	struct sgx_add_page_req *req;
+	bool skip_rest = false;
+	bool is_empty = false;
+	struct sgx_encl *encl;
+	struct sgx_epc_page *epc_page;
+
+	encl = container_of(work, struct sgx_encl, work);
+
+	do {
+		schedule();
+
+		mutex_lock(&encl->lock);
+		if (encl->flags & SGX_ENCL_DEAD)
+			skip_rest = true;
+
+		req = list_first_entry(&encl->add_page_reqs,
+				       struct sgx_add_page_req, list);
+		list_del(&req->list);
+		is_empty = list_empty(&encl->add_page_reqs);
+		mutex_unlock(&encl->lock);
+
+		if (skip_rest)
+			goto next;
+
+		epc_page = sgx_alloc_page();
+
+		mutex_lock(&encl->lock);
+
+		if (IS_ERR(epc_page)) {
+			sgx_encl_destroy(encl);
+			skip_rest = true;
+		} else if (!sgx_process_add_page_req(req, epc_page)) {
+			sgx_free_page(epc_page);
+			sgx_encl_destroy(encl);
+			skip_rest = true;
+		}
+
+		mutex_unlock(&encl->lock);
+
+next:
+		kfree(req);
+	} while (!kref_put(&encl->refcount, sgx_encl_release) && !is_empty);
+}
+
+static u32 sgx_calc_ssaframesize(u32 miscselect, u64 xfrm)
+{
+	u32 size_max = PAGE_SIZE;
+	u32 size;
+	int i;
+
+	for (i = 2; i < 64; i++) {
+		if (!((1 << i) & xfrm))
+			continue;
+
+		size = SGX_SSA_GPRS_SIZE + sgx_xsave_size_tbl[i];
+		if (miscselect & SGX_MISC_EXINFO)
+			size += SGX_SSA_MISC_EXINFO_SIZE;
+
+		if (size > size_max)
+			size_max = size;
+	}
+
+	return PFN_UP(size_max);
+}
+
+static int sgx_validate_secs(const struct sgx_secs *secs,
+			     unsigned long ssaframesize)
+{
+	if (secs->size < (2 * PAGE_SIZE) || !is_power_of_2(secs->size))
+		return -EINVAL;
+
+	if (secs->base & (secs->size - 1))
+		return -EINVAL;
+
+	if (secs->miscselect & sgx_misc_reserved_mask ||
+	    secs->attributes & sgx_attributes_reserved_mask ||
+	    secs->xfrm & sgx_xfrm_reserved_mask)
+		return -EINVAL;
+
+	if (secs->attributes & SGX_ATTR_MODE64BIT) {
+		if (secs->size > sgx_encl_size_max_64)
+			return -EINVAL;
+	} else if (secs->size > sgx_encl_size_max_32)
+		return -EINVAL;
+
+	if (!(secs->xfrm & XFEATURE_MASK_FP) ||
+	    !(secs->xfrm & XFEATURE_MASK_SSE) ||
+	    (((secs->xfrm >> XFEATURE_BNDREGS) & 1) !=
+	     ((secs->xfrm >> XFEATURE_BNDCSR) & 1)))
+		return -EINVAL;
+
+	if (!secs->ssa_frame_size || ssaframesize > secs->ssa_frame_size)
+		return -EINVAL;
+
+	if (memchr_inv(secs->reserved1, 0, SGX_SECS_RESERVED1_SIZE) ||
+	    memchr_inv(secs->reserved2, 0, SGX_SECS_RESERVED2_SIZE) ||
+	    memchr_inv(secs->reserved3, 0, SGX_SECS_RESERVED3_SIZE) ||
+	    memchr_inv(secs->reserved4, 0, SGX_SECS_RESERVED4_SIZE))
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct sgx_encl *sgx_encl_alloc(struct sgx_secs *secs)
+{
+	unsigned long encl_size = secs->size + PAGE_SIZE;
+	unsigned long ssaframesize;
+	struct sgx_encl_mm *mm;
+	struct sgx_encl *encl;
+	struct file *backing;
+
+	ssaframesize = sgx_calc_ssaframesize(secs->miscselect, secs->xfrm);
+	if (sgx_validate_secs(secs, ssaframesize))
+		return ERR_PTR(-EINVAL);
+
+	backing = shmem_file_setup("SGX backing", encl_size + (encl_size >> 5),
+				   VM_NORESERVE);
+	if (IS_ERR(backing))
+		return ERR_CAST(backing);
+
+	encl = kzalloc(sizeof(*encl), GFP_KERNEL);
+	if (!encl) {
+		fput(backing);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	mm = kzalloc(sizeof(*mm), GFP_KERNEL);
+	if (!mm) {
+		kfree(encl);
+		fput(backing);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	encl->secs_attributes = secs->attributes;
+	encl->allowed_attributes = SGX_ATTR_ALLOWED_MASK;
+	kref_init(&encl->refcount);
+	INIT_LIST_HEAD(&encl->add_page_reqs);
+	INIT_RADIX_TREE(&encl->page_tree, GFP_KERNEL);
+	mutex_init(&encl->lock);
+	INIT_WORK(&encl->work, sgx_add_page_worker);
+	INIT_LIST_HEAD(&encl->mm_list);
+	list_add(&mm->list, &encl->mm_list);
+	kref_init(&mm->refcount);
+	mm->mm = current->mm;
+	mm->encl = encl;
+	spin_lock_init(&encl->mm_lock);
+	encl->base = secs->base;
+	encl->size = secs->size;
+	encl->ssaframesize = secs->ssa_frame_size;
+	encl->backing = backing;
+
+	return encl;
+}
+
+static struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
+						 unsigned long addr)
+{
+	struct sgx_encl_page *encl_page;
+	int ret;
+
+	if (radix_tree_lookup(&encl->page_tree, PFN_DOWN(addr)))
+		return ERR_PTR(-EEXIST);
+	encl_page = kzalloc(sizeof(*encl_page), GFP_KERNEL);
+	if (!encl_page)
+		return ERR_PTR(-ENOMEM);
+	encl_page->desc = addr;
+	encl_page->encl = encl;
+	ret = radix_tree_insert(&encl->page_tree, PFN_DOWN(encl_page->desc),
+				encl_page);
+	if (ret) {
+		kfree(encl_page);
+		return ERR_PTR(ret);
+	}
+	return encl_page;
+}
+
+static int sgx_encl_pm_notifier(struct notifier_block *nb,
+				unsigned long action, void *data)
+{
+	struct sgx_encl *encl = container_of(nb, struct sgx_encl, pm_notifier);
+
+	if (action != PM_SUSPEND_PREPARE && action != PM_HIBERNATION_PREPARE)
+		return NOTIFY_DONE;
+
+	mutex_lock(&encl->lock);
+	sgx_encl_destroy(encl);
+	encl->flags |= SGX_ENCL_SUSPEND;
+	mutex_unlock(&encl->lock);
+	flush_work(&encl->work);
+	return NOTIFY_DONE;
+}
+
+static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs)
+{
+	struct vm_area_struct *vma;
+	struct sgx_pageinfo pginfo;
+	struct sgx_secinfo secinfo;
+	struct sgx_epc_page *secs_epc;
+	long ret;
+
+	secs_epc = sgx_alloc_page();
+	if (IS_ERR(secs_epc)) {
+		ret = PTR_ERR(secs_epc);
+		return ret;
+	}
+
+	encl->secs.encl = encl;
+	encl->secs.epc_page = secs_epc;
+
+	pginfo.addr = 0;
+	pginfo.contents = (unsigned long)secs;
+	pginfo.metadata = (unsigned long)&secinfo;
+	pginfo.secs = 0;
+	memset(&secinfo, 0, sizeof(secinfo));
+	ret = __ecreate((void *)&pginfo, sgx_epc_addr(secs_epc));
+
+	if (ret) {
+		pr_debug("ECREATE returned %ld\n", ret);
+		return ret;
+	}
+
+	if (secs->attributes & SGX_ATTR_DEBUG)
+		encl->flags |= SGX_ENCL_DEBUG;
+
+	encl->pm_notifier.notifier_call = &sgx_encl_pm_notifier;
+	ret = register_pm_notifier(&encl->pm_notifier);
+	if (ret) {
+		encl->pm_notifier.notifier_call = NULL;
+		return ret;
+	}
+
+	down_read(&current->mm->mmap_sem);
+	ret = sgx_encl_find(current->mm, secs->base, &vma);
+	if (ret != -ENOENT) {
+		if (!ret)
+			ret = -EINVAL;
+		up_read(&current->mm->mmap_sem);
+		return ret;
+	}
+
+	if (vma->vm_start != secs->base ||
+	    vma->vm_end != (secs->base + secs->size) ||
+	    vma->vm_pgoff != 0) {
+		ret = -EINVAL;
+		up_read(&current->mm->mmap_sem);
+		return ret;
+	}
+
+	vma->vm_private_data = encl;
+	up_read(&current->mm->mmap_sem);
+	return 0;
+}
+
+/**
+ * sgx_ioc_enclave_create - handler for %SGX_IOC_ENCLAVE_CREATE
+ * @filep:	open file to /dev/sgx
+ * @cmd:	the command value
+ * @arg:	pointer to an &sgx_enclave_create instance
+ *
+ * Validates SECS attributes, allocates an EPC page for the SECS and performs
+ * ECREATE.
+ *
+ * Return:
+ *   0 on success,
+ *   -errno otherwise
+ */
+static long sgx_ioc_enclave_create(struct file *filep, unsigned int cmd,
+				   unsigned long arg)
+{
+	struct sgx_enclave_create *createp = (struct sgx_enclave_create *)arg;
+	struct page *secs_page;
+	struct sgx_secs *secs;
+	struct sgx_encl *encl;
+	int ret;
+
+	secs_page = alloc_page(GFP_HIGHUSER);
+	if (!secs_page)
+		return -ENOMEM;
+
+	secs = kmap(secs_page);
+	if (copy_from_user(secs, (void __user *)createp->src, sizeof(*secs))) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	encl = sgx_encl_alloc(secs);
+	if (IS_ERR(encl)) {
+		ret = PTR_ERR(encl);
+		goto out;
+	}
+
+	ret = sgx_encl_create(encl, secs);
+	if (ret)
+		kref_put(&encl->refcount, sgx_encl_release);
+
+out:
+	kunmap(secs_page);
+	__free_page(secs_page);
+	return ret;
+}
+
+static int sgx_validate_secinfo(struct sgx_secinfo *secinfo)
+{
+	u64 page_type = secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK;
+	u64 perm = secinfo->flags & SGX_SECINFO_PERMISSION_MASK;
+	int i;
+
+	if ((secinfo->flags & SGX_SECINFO_RESERVED_MASK) ||
+	    ((perm & SGX_SECINFO_W) && !(perm & SGX_SECINFO_R)) ||
+	    (page_type != SGX_SECINFO_TCS && page_type != SGX_SECINFO_TRIM &&
+	     page_type != SGX_SECINFO_REG))
+		return -EINVAL;
+
+	for (i = 0; i < SGX_SECINFO_RESERVED_SIZE; i++)
+		if (secinfo->reserved[i])
+			return -EINVAL;
+
+	return 0;
+}
+
+static bool sgx_validate_offset(struct sgx_encl *encl, unsigned long offset)
+{
+	if (offset & (PAGE_SIZE - 1))
+		return false;
+
+	if (offset >= encl->size)
+		return false;
+
+	return true;
+}
+
+static int sgx_validate_tcs(struct sgx_encl *encl, struct sgx_tcs *tcs)
+{
+	int i;
+
+	if (tcs->flags & SGX_TCS_RESERVED_MASK)
+		return -EINVAL;
+
+	if (tcs->flags & SGX_TCS_DBGOPTIN)
+		return -EINVAL;
+
+	if (!sgx_validate_offset(encl, tcs->ssa_offset))
+		return -EINVAL;
+
+	if (!sgx_validate_offset(encl, tcs->fs_offset))
+		return -EINVAL;
+
+	if (!sgx_validate_offset(encl, tcs->gs_offset))
+		return -EINVAL;
+
+	if ((tcs->fs_limit & 0xFFF) != 0xFFF)
+		return -EINVAL;
+
+	if ((tcs->gs_limit & 0xFFF) != 0xFFF)
+		return -EINVAL;
+
+	for (i = 0; i < SGX_TCS_RESERVED_SIZE; i++)
+		if (tcs->reserved[i])
+			return -EINVAL;
+
+	return 0;
+}
+
+static int __sgx_encl_add_page(struct sgx_encl *encl,
+			       struct sgx_encl_page *encl_page,
+			       void *data,
+			       struct sgx_secinfo *secinfo,
+			       unsigned int mrmask)
+{
+	unsigned long page_index = sgx_encl_get_index(encl, encl_page);
+	u64 page_type = secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK;
+	struct sgx_add_page_req *req = NULL;
+	struct page *backing;
+	void *backing_ptr;
+	int empty;
+
+	req = kzalloc(sizeof(*req), GFP_KERNEL);
+	if (!req)
+		return -ENOMEM;
+
+	backing = sgx_encl_get_backing_page(encl, page_index);
+	if (IS_ERR(backing)) {
+		kfree(req);
+		return PTR_ERR(backing);
+	}
+
+	backing_ptr = kmap(backing);
+	memcpy(backing_ptr, data, PAGE_SIZE);
+	kunmap(backing);
+	if (page_type == SGX_SECINFO_TCS)
+		encl_page->desc |= SGX_ENCL_PAGE_TCS;
+	memcpy(&req->secinfo, secinfo, sizeof(*secinfo));
+	req->encl = encl;
+	req->encl_page = encl_page;
+	req->mrmask = mrmask;
+	empty = list_empty(&encl->add_page_reqs);
+	kref_get(&encl->refcount);
+	list_add_tail(&req->list, &encl->add_page_reqs);
+	if (empty)
+		queue_work(sgx_encl_wq, &encl->work);
+	set_page_dirty(backing);
+	put_page(backing);
+	return 0;
+}
+
+static int sgx_encl_add_page(struct sgx_encl *encl, unsigned long addr,
+			     void *data, struct sgx_secinfo *secinfo,
+			     unsigned int mrmask)
+{
+	u64 page_type = secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK;
+	struct sgx_encl_page *encl_page;
+	int ret;
+
+	if (sgx_validate_secinfo(secinfo))
+		return -EINVAL;
+	if (page_type == SGX_SECINFO_TCS) {
+		ret = sgx_validate_tcs(encl, data);
+		if (ret)
+			return ret;
+	}
+
+	mutex_lock(&encl->lock);
+
+	if (encl->flags & (SGX_ENCL_INITIALIZED | SGX_ENCL_DEAD)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	encl_page = sgx_encl_page_alloc(encl, addr);
+	if (IS_ERR(encl_page)) {
+		ret = PTR_ERR(encl_page);
+		goto out;
+	}
+
+	ret = __sgx_encl_add_page(encl, encl_page, data, secinfo, mrmask);
+	if (ret) {
+		radix_tree_delete(&encl_page->encl->page_tree,
+				  PFN_DOWN(encl_page->desc));
+		kfree(encl_page);
+	}
+
+out:
+	mutex_unlock(&encl->lock);
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_add_page - handler for %SGX_IOC_ENCLAVE_ADD_PAGE
+ *
+ * @filep:	open file to /dev/sgx
+ * @cmd:	the command value
+ * @arg:	pointer to an &sgx_enclave_add_page instance
+ *
+ * Creates a new enclave page and enqueues an EADD operation that will be
+ * processed by a worker thread later on.
+ *
+ * Return:
+ *   0 on success,
+ *   -errno otherwise
+ */
+static long sgx_ioc_enclave_add_page(struct file *filep, unsigned int cmd,
+				     unsigned long arg)
+{
+	struct sgx_enclave_add_page *addp = (void *)arg;
+	struct sgx_secinfo secinfo;
+	struct sgx_encl *encl;
+	struct page *data_page;
+	void *data;
+	int ret;
+
+	ret = sgx_encl_get(addp->addr, &encl);
+	if (ret)
+		return ret;
+
+	if (copy_from_user(&secinfo, (void __user *)addp->secinfo,
+			   sizeof(secinfo))) {
+		kref_put(&encl->refcount, sgx_encl_release);
+		return -EFAULT;
+	}
+
+	data_page = alloc_page(GFP_HIGHUSER);
+	if (!data_page) {
+		kref_put(&encl->refcount, sgx_encl_release);
+		return -ENOMEM;
+	}
+
+	data = kmap(data_page);
+
+	if (copy_from_user((void *)data, (void __user *)addp->src, PAGE_SIZE)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	ret = sgx_encl_add_page(encl, addp->addr, data, &secinfo, addp->mrmask);
+	if (ret)
+		goto out;
+
+out:
+	kref_put(&encl->refcount, sgx_encl_release);
+	kunmap(data_page);
+	__free_page(data_page);
+	return ret;
+}
+
+static int __sgx_get_key_hash(struct crypto_shash *tfm, const void *modulus,
+			      void *hash)
+{
+	SHASH_DESC_ON_STACK(shash, tfm);
+
+	shash->tfm = tfm;
+	shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+	return crypto_shash_digest(shash, modulus, SGX_MODULUS_SIZE, hash);
+}
+
+static int sgx_get_key_hash(const void *modulus, void *hash)
+{
+	struct crypto_shash *tfm;
+	int ret;
+
+	tfm = crypto_alloc_shash("sha256", 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	ret = __sgx_get_key_hash(tfm, modulus, hash);
+
+	crypto_free_shash(tfm);
+	return ret;
+}
+
+static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct,
+			 struct sgx_einittoken *token)
+{
+	u64 mrsigner[4];
+	int ret;
+	int i;
+	int j;
+
+	/* Check that the required attributes have been authorized. */
+	if (encl->secs_attributes & ~encl->allowed_attributes)
+		return -EINVAL;
+
+	ret = sgx_get_key_hash(sigstruct->modulus, mrsigner);
+	if (ret)
+		return ret;
+
+	flush_work(&encl->work);
+
+	mutex_lock(&encl->lock);
+
+	if (encl->flags & SGX_ENCL_INITIALIZED)
+		goto err_out;
+
+	if (encl->flags & SGX_ENCL_DEAD) {
+		ret = -EFAULT;
+		goto err_out;
+	}
+
+	for (i = 0; i < SGX_EINIT_SLEEP_COUNT; i++) {
+		for (j = 0; j < SGX_EINIT_SPIN_COUNT; j++) {
+			ret = sgx_einit(sigstruct, token, encl->secs.epc_page,
+					mrsigner);
+			if (ret == SGX_UNMASKED_EVENT)
+				continue;
+			else
+				break;
+		}
+
+		if (ret != SGX_UNMASKED_EVENT)
+			break;
+
+		msleep_interruptible(SGX_EINIT_SLEEP_TIME);
+
+		if (signal_pending(current)) {
+			ret = -ERESTARTSYS;
+			goto err_out;
+		}
+	}
+
+	if (encls_faulted(ret)) {
+		if (encls_failed(ret))
+			ENCLS_WARN(ret, "EINIT");
+
+		sgx_encl_destroy(encl);
+		ret = -EFAULT;
+	} else if (encls_returned_code(ret)) {
+		pr_debug("EINIT returned %d\n", ret);
+	} else {
+		encl->flags |= SGX_ENCL_INITIALIZED;
+	}
+
+err_out:
+	mutex_unlock(&encl->lock);
+	return ret;
+}
+
+/**
+ * sgx_ioc_enclave_init - handler for %SGX_IOC_ENCLAVE_INIT
+ *
+ * @filep:	open file to /dev/sgx
+ * @cmd:	the command value
+ * @arg:	pointer to an &sgx_enclave_init instance
+ *
+ * Flushes the remaining enqueued EADD operations and performs EINIT.
+ *
+ * Return:
+ *   0 on success,
+ *   SGX error code on EINIT failure,
+ *   -errno otherwise
+ */
+static long sgx_ioc_enclave_init(struct file *filep, unsigned int cmd,
+				 unsigned long arg)
+{
+	struct sgx_enclave_init *initp = (struct sgx_enclave_init *)arg;
+	struct sgx_sigstruct *sigstruct;
+	struct sgx_einittoken *einittoken;
+	struct sgx_encl *encl;
+	struct page *initp_page;
+	int ret;
+
+	initp_page = alloc_page(GFP_HIGHUSER);
+	if (!initp_page)
+		return -ENOMEM;
+
+	sigstruct = kmap(initp_page);
+	einittoken = (struct sgx_einittoken *)
+		((unsigned long)sigstruct + PAGE_SIZE / 2);
+	memset(einittoken, 0, sizeof(*einittoken));
+
+	if (copy_from_user(sigstruct, (void __user *)initp->sigstruct,
+			   sizeof(*sigstruct))) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	ret = sgx_encl_get(initp->addr, &encl);
+	if (ret)
+		goto out;
+
+	ret = sgx_encl_init(encl, sigstruct, einittoken);
+
+	kref_put(&encl->refcount, sgx_encl_release);
+
+out:
+	kunmap(initp_page);
+	__free_page(initp_page);
+	return ret;
+}
+
+typedef long (*sgx_ioc_t)(struct file *filep, unsigned int cmd,
+			  unsigned long arg);
+
+long sgx_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
+{
+	char data[256];
+	sgx_ioc_t handler = NULL;
+	long ret;
+
+	switch (cmd) {
+	case SGX_IOC_ENCLAVE_CREATE:
+		handler = sgx_ioc_enclave_create;
+		break;
+	case SGX_IOC_ENCLAVE_ADD_PAGE:
+		handler = sgx_ioc_enclave_add_page;
+		break;
+	case SGX_IOC_ENCLAVE_INIT:
+		handler = sgx_ioc_enclave_init;
+		break;
+	default:
+		return -ENOIOCTLCMD;
+	}
+
+	if (copy_from_user(data, (void __user *)arg, _IOC_SIZE(cmd)))
+		return -EFAULT;
+
+	ret = handler(filep, cmd, (unsigned long)((void *)data));
+	if (!ret && (cmd & IOC_OUT)) {
+		if (copy_to_user((void __user *)arg, data, _IOC_SIZE(cmd)))
+			return -EFAULT;
+	}
+
+	return ret;
+}
diff --git a/arch/x86/kernel/cpu/sgx/driver/main.c b/arch/x86/kernel/cpu/sgx/driver/main.c
new file mode 100644
index 000000000000..16f36cd0af04
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/driver/main.c
@@ -0,0 +1,290 @@ 
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2016-18 Intel Corporation.
+
+#include <linux/acpi.h>
+#include <linux/cdev.h>
+#include <linux/mman.h>
+#include <linux/platform_device.h>
+#include <linux/security.h>
+#include <linux/suspend.h>
+#include <asm/traps.h>
+#include "driver.h"
+
+MODULE_DESCRIPTION("Intel SGX Enclave Driver");
+MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");
+MODULE_LICENSE("Dual BSD/GPL");
+
+struct workqueue_struct *sgx_encl_wq;
+u64 sgx_encl_size_max_32;
+u64 sgx_encl_size_max_64;
+u32 sgx_misc_reserved_mask;
+u64 sgx_attributes_reserved_mask;
+u64 sgx_xfrm_reserved_mask = ~0x3;
+u32 sgx_xsave_size_tbl[64];
+
+#ifdef CONFIG_COMPAT
+static long sgx_compat_ioctl(struct file *filep, unsigned int cmd,
+			      unsigned long arg)
+{
+	return sgx_ioctl(filep, cmd, arg);
+}
+#endif
+
+static int sgx_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	vma->vm_ops = &sgx_vm_ops;
+	vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP | VM_IO;
+
+	return 0;
+}
+
+static unsigned long sgx_get_unmapped_area(struct file *file,
+					   unsigned long addr,
+					   unsigned long len,
+					   unsigned long pgoff,
+					   unsigned long flags)
+{
+	if (len < 2 * PAGE_SIZE || len & (len - 1) || flags & MAP_PRIVATE)
+		return -EINVAL;
+
+	addr = current->mm->get_unmapped_area(file, addr, 2 * len, pgoff,
+					      flags);
+	if (IS_ERR_VALUE(addr))
+		return addr;
+
+	addr = (addr + (len - 1)) & ~(len - 1);
+
+	return addr;
+}
+
+static const struct file_operations sgx_ctrl_fops = {
+	.owner			= THIS_MODULE,
+	.unlocked_ioctl		= sgx_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl		= sgx_compat_ioctl,
+#endif
+	.mmap			= sgx_mmap,
+	.get_unmapped_area	= sgx_get_unmapped_area,
+};
+
+static struct bus_type sgx_bus_type = {
+	.name	= "sgx",
+};
+
+static char *sgx_devnode(struct device *dev, umode_t *mode,
+			 kuid_t *uid, kgid_t *gid)
+{
+	if (mode)
+		*mode = 0666;
+	return kasprintf(GFP_KERNEL, "sgx");
+}
+
+static const struct device_type sgx_device_type = {
+	.name = "sgx",
+	.devnode = sgx_devnode,
+};
+
+struct sgx_dev_ctx {
+	struct device ctrl_dev;
+	struct cdev ctrl_cdev;
+};
+
+static dev_t sgx_devt;
+
+static void sgx_dev_release(struct device *dev)
+{
+	struct sgx_dev_ctx *ctx = container_of(dev, struct sgx_dev_ctx,
+					       ctrl_dev);
+
+	kfree(ctx);
+}
+
+static struct sgx_dev_ctx *sgx_dev_ctx_alloc(struct device *parent)
+{
+	struct sgx_dev_ctx *ctx;
+	int ret;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return ERR_PTR(-ENOMEM);
+
+	device_initialize(&ctx->ctrl_dev);
+
+	ctx->ctrl_dev.bus = &sgx_bus_type;
+	ctx->ctrl_dev.type = &sgx_device_type;
+	ctx->ctrl_dev.parent = parent;
+	ctx->ctrl_dev.devt = MKDEV(MAJOR(sgx_devt), 0);
+	ctx->ctrl_dev.release = sgx_dev_release;
+
+	ret = dev_set_name(&ctx->ctrl_dev, "sgx");
+	if (ret) {
+		put_device(&ctx->ctrl_dev);
+		return ERR_PTR(ret);
+	}
+
+	cdev_init(&ctx->ctrl_cdev, &sgx_ctrl_fops);
+	ctx->ctrl_cdev.owner = THIS_MODULE;
+
+	dev_set_drvdata(parent, ctx);
+
+	return ctx;
+}
+
+static struct sgx_dev_ctx *sgxm_dev_ctx_alloc(struct device *parent)
+{
+	struct sgx_dev_ctx *ctx;
+	int rc;
+
+	ctx = sgx_dev_ctx_alloc(parent);
+	if (IS_ERR(ctx))
+		return ctx;
+
+	rc = devm_add_action_or_reset(parent, (void (*)(void *))put_device,
+				      &ctx->ctrl_dev);
+	if (rc)
+		return ERR_PTR(rc);
+
+	return ctx;
+}
+
+static int sgx_dev_init(struct device *parent)
+{
+	struct sgx_dev_ctx *sgx_dev;
+	unsigned int eax;
+	unsigned int ebx;
+	unsigned int ecx;
+	unsigned int edx;
+	u64 attr_mask;
+	u64 xfrm_mask;
+	int ret;
+	int i;
+
+	cpuid_count(SGX_CPUID, 0, &eax, &ebx, &ecx, &edx);
+	sgx_misc_reserved_mask = ~ebx | SGX_MISC_RESERVED_MASK;
+	sgx_encl_size_max_64 = 1ULL << ((edx >> 8) & 0xFF);
+	sgx_encl_size_max_32 = 1ULL << (edx & 0xFF);
+
+	cpuid_count(SGX_CPUID, 1, &eax, &ebx, &ecx, &edx);
+
+	attr_mask = (((u64)ebx) << 32) + (u64)eax;
+	sgx_attributes_reserved_mask = ~attr_mask | SGX_ATTR_RESERVED_MASK;
+
+	if (boot_cpu_has(X86_FEATURE_OSXSAVE)) {
+		xfrm_mask = (((u64)edx) << 32) + (u64)ecx;
+
+		for (i = 2; i < 64; i++) {
+			cpuid_count(0x0D, i, &eax, &ebx, &ecx, &edx);
+			if ((1 << i) & xfrm_mask)
+				sgx_xsave_size_tbl[i] = eax + ebx;
+		}
+
+		sgx_xfrm_reserved_mask = ~xfrm_mask;
+	}
+
+	sgx_dev = sgxm_dev_ctx_alloc(parent);
+	if (IS_ERR(sgx_dev))
+		return PTR_ERR(sgx_dev);
+
+	sgx_encl_wq = alloc_workqueue("sgx-encl-wq",
+				      WQ_UNBOUND | WQ_FREEZABLE, 1);
+	if (!sgx_encl_wq)
+		return -ENOMEM;
+
+	ret = cdev_device_add(&sgx_dev->ctrl_cdev, &sgx_dev->ctrl_dev);
+	if (ret)
+		goto err_device_add;
+
+	return 0;
+
+err_device_add:
+	destroy_workqueue(sgx_encl_wq);
+	return ret;
+}
+
+static int sgx_drv_probe(struct platform_device *pdev)
+{
+	if (!sgx_enabled) {
+		pr_info("sgx: SGX is not enabled in the core\n");
+		return -ENODEV;
+	}
+
+	if (!boot_cpu_has(X86_FEATURE_SGX_LC)) {
+		pr_info("sgx: The public key MSRs are not writable\n");
+		return -ENODEV;
+	}
+
+	return sgx_dev_init(&pdev->dev);
+}
+
+static int sgx_drv_remove(struct platform_device *pdev)
+{
+	struct sgx_dev_ctx *ctx = dev_get_drvdata(&pdev->dev);
+
+	cdev_device_del(&ctx->ctrl_cdev, &ctx->ctrl_dev);
+	destroy_workqueue(sgx_encl_wq);
+
+	return 0;
+}
+
+#ifdef CONFIG_ACPI
+static struct acpi_device_id sgx_device_ids[] = {
+	{"INT0E0C", 0},
+	{"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, sgx_device_ids);
+#endif
+
+static struct platform_driver sgx_drv = {
+	.probe = sgx_drv_probe,
+	.remove = sgx_drv_remove,
+	.driver = {
+		.name			= "sgx",
+		.acpi_match_table	= ACPI_PTR(sgx_device_ids),
+	},
+};
+
+static int __init sgx_drv_subsys_init(void)
+{
+	int ret;
+
+	ret = bus_register(&sgx_bus_type);
+	if (ret)
+		return ret;
+
+	ret = alloc_chrdev_region(&sgx_devt, 0, SGX_DRV_NR_DEVICES, "sgx");
+	if (ret < 0) {
+		bus_unregister(&sgx_bus_type);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void sgx_drv_subsys_exit(void)
+{
+	bus_unregister(&sgx_bus_type);
+	unregister_chrdev_region(sgx_devt, SGX_DRV_NR_DEVICES);
+}
+
+static int __init sgx_drv_init(void)
+{
+	int ret;
+
+	ret = sgx_drv_subsys_init();
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&sgx_drv);
+	if (ret)
+		sgx_drv_subsys_exit();
+
+	return ret;
+}
+module_init(sgx_drv_init);
+
+static void __exit sgx_drv_exit(void)
+{
+	platform_driver_unregister(&sgx_drv);
+	sgx_drv_subsys_exit();
+}
+module_exit(sgx_drv_exit);
diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
new file mode 100644
index 000000000000..bd8bcd748976
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/encl.c
@@ -0,0 +1,358 @@ 
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2016-18 Intel Corporation.
+
+#include <linux/mm.h>
+#include <linux/shmem_fs.h>
+#include <linux/suspend.h>
+#include <linux/sched/mm.h>
+#include "arch.h"
+#include "encl.h"
+#include "sgx.h"
+
+static struct sgx_encl_page *sgx_encl_load_page(struct sgx_encl *encl,
+						unsigned long addr)
+{
+	struct sgx_encl_page *entry;
+
+	/* If process was forked, VMA is still there but vm_private_data is set
+	 * to NULL.
+	 */
+	if (!encl)
+		return ERR_PTR(-EFAULT);
+
+	if ((encl->flags & SGX_ENCL_DEAD) ||
+	    !(encl->flags & SGX_ENCL_INITIALIZED))
+		return ERR_PTR(-EFAULT);
+
+	entry = radix_tree_lookup(&encl->page_tree, addr >> PAGE_SHIFT);
+	if (!entry)
+		return ERR_PTR(-EFAULT);
+
+	/* Page is already resident in the EPC. */
+	if (entry->epc_page)
+		return entry;
+
+	return ERR_PTR(-EFAULT);
+}
+
+static struct sgx_encl_mm *sgx_encl_get_mm(struct sgx_encl *encl,
+					   struct mm_struct *mm)
+{
+	struct sgx_encl_mm *next_mm = NULL;
+	struct sgx_encl_mm *prev_mm = NULL;
+	int iter;
+
+	while (true) {
+		next_mm = sgx_encl_next_mm(encl, prev_mm, &iter);
+		if (prev_mm) {
+			mmdrop(prev_mm->mm);
+			kref_put(&prev_mm->refcount, sgx_encl_release_mm);
+		}
+		prev_mm = next_mm;
+
+		if (iter == SGX_ENCL_MM_ITER_DONE)
+			break;
+
+		if (iter == SGX_ENCL_MM_ITER_RESTART)
+			continue;
+
+		if (mm == next_mm->mm)
+			return next_mm;
+	}
+
+	return NULL;
+}
+
+static void sgx_vma_open(struct vm_area_struct *vma)
+{
+	struct sgx_encl *encl = vma->vm_private_data;
+	struct sgx_encl_mm *mm;
+
+	if (!encl)
+		return;
+
+	if (encl->flags & SGX_ENCL_DEAD)
+		goto out;
+
+	mm = sgx_encl_get_mm(encl, vma->vm_mm);
+	if (!mm) {
+		mm = kzalloc(sizeof(*mm), GFP_KERNEL);
+		if (!mm) {
+			encl->flags |= SGX_ENCL_DEAD;
+			goto out;
+		}
+
+		spin_lock(&encl->mm_lock);
+		mm->encl = encl;
+		mm->mm = vma->vm_mm;
+		list_add(&mm->list, &encl->mm_list);
+		kref_init(&mm->refcount);
+		spin_unlock(&encl->mm_lock);
+	} else {
+		mmdrop(mm->mm);
+	}
+
+out:
+	kref_get(&encl->refcount);
+}
+
+static void sgx_vma_close(struct vm_area_struct *vma)
+{
+	struct sgx_encl *encl = vma->vm_private_data;
+	struct sgx_encl_mm *mm;
+
+	if (!encl)
+		return;
+
+	mm = sgx_encl_get_mm(encl, vma->vm_mm);
+	if (mm) {
+		mmdrop(mm->mm);
+		kref_put(&mm->refcount, sgx_encl_release_mm);
+
+		/* Release kref for the VMA. */
+		kref_put(&mm->refcount, sgx_encl_release_mm);
+	}
+
+	kref_put(&encl->refcount, sgx_encl_release);
+}
+
+static unsigned int sgx_vma_fault(struct vm_fault *vmf)
+{
+	unsigned long addr = (unsigned long)vmf->address;
+	struct vm_area_struct *vma = vmf->vma;
+	struct sgx_encl *encl = vma->vm_private_data;
+	struct sgx_encl_page *entry;
+	int ret = VM_FAULT_NOPAGE;
+	struct sgx_encl_mm *mm;
+	unsigned long pfn;
+
+	mm = sgx_encl_get_mm(encl, vma->vm_mm);
+	if (!mm)
+		return VM_FAULT_SIGBUS;
+
+	mmdrop(mm->mm);
+	kref_put(&mm->refcount, sgx_encl_release_mm);
+
+	mutex_lock(&encl->lock);
+
+	entry = sgx_encl_load_page(encl, addr);
+	if (IS_ERR(entry)) {
+		if (unlikely(PTR_ERR(entry) != -EBUSY))
+			ret = VM_FAULT_SIGBUS;
+
+		goto out;
+	}
+
+	if (!follow_pfn(vma, addr, &pfn))
+		goto out;
+
+	ret = vmf_insert_pfn(vma, addr, PFN_DOWN(entry->epc_page->desc));
+	if (ret != VM_FAULT_NOPAGE) {
+		ret = VM_FAULT_SIGBUS;
+		goto out;
+	}
+
+out:
+	mutex_unlock(&encl->lock);
+	return ret;
+}
+
+const struct vm_operations_struct sgx_vm_ops = {
+	.close = sgx_vma_close,
+	.open = sgx_vma_open,
+	.fault = sgx_vma_fault,
+};
+EXPORT_SYMBOL_GPL(sgx_vm_ops);
+
+/**
+ * sgx_encl_find - find an enclave
+ * @mm:		mm struct of the current process
+ * @addr:	address in the ELRANGE
+ * @vma:	the resulting VMA
+ *
+ * Find an enclave identified by the given address. Give back a VMA that is
+ * part of the enclave and located in that address. The VMA is given back if it
+ * is a proper enclave VMA even if an &sgx_encl instance does not exist yet
+ * (enclave creation has not been performed).
+ *
+ * Return:
+ *   0 on success,
+ *   -EINVAL if an enclave was not found,
+ *   -ENOENT if the enclave has not been created yet
+ */
+int sgx_encl_find(struct mm_struct *mm, unsigned long addr,
+		  struct vm_area_struct **vma)
+{
+	struct vm_area_struct *result;
+	struct sgx_encl *encl;
+
+	result = find_vma(mm, addr);
+	if (!result || result->vm_ops != &sgx_vm_ops || addr < result->vm_start)
+		return -EINVAL;
+
+	encl = result->vm_private_data;
+	*vma = result;
+
+	return encl ? 0 : -ENOENT;
+}
+EXPORT_SYMBOL_GPL(sgx_encl_find);
+
+/**
+ * sgx_encl_destroy() - destroy enclave resources
+ * @encl:	an &sgx_encl instance
+ */
+void sgx_encl_destroy(struct sgx_encl *encl)
+{
+	struct sgx_encl_page *entry;
+	struct radix_tree_iter iter;
+	void **slot;
+
+	encl->flags |= SGX_ENCL_DEAD;
+
+	radix_tree_for_each_slot(slot, &encl->page_tree, &iter, 0) {
+		entry = *slot;
+		if (entry->epc_page) {
+			if (!__sgx_free_page(entry->epc_page)) {
+				encl->secs_child_cnt--;
+				entry->epc_page = NULL;
+
+			}
+
+			radix_tree_delete(&entry->encl->page_tree,
+					  PFN_DOWN(entry->desc));
+		}
+	}
+
+	if (!encl->secs_child_cnt && encl->secs.epc_page) {
+		sgx_free_page(encl->secs.epc_page);
+		encl->secs.epc_page = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(sgx_encl_destroy);
+
+/**
+ * sgx_encl_release - Destroy an enclave instance
+ * @kref:	address of a kref inside &sgx_encl
+ *
+ * Used together with kref_put(). Frees all the resources associated with the
+ * enclave and the instance itself.
+ */
+void sgx_encl_release(struct kref *ref)
+{
+	struct sgx_encl *encl = container_of(ref, struct sgx_encl, refcount);
+	struct sgx_encl_mm *mm;
+
+	if (encl->pm_notifier.notifier_call)
+		unregister_pm_notifier(&encl->pm_notifier);
+
+	sgx_encl_destroy(encl);
+
+	if (encl->backing)
+		fput(encl->backing);
+
+	/* If sgx_encl_create() fails, can be non-empty */
+	while (!list_empty(&encl->mm_list)) {
+		mm = list_first_entry(&encl->mm_list, struct sgx_encl_mm, list);
+		list_del(&mm->list);
+		kfree(mm);
+	}
+
+	kfree(encl);
+}
+EXPORT_SYMBOL_GPL(sgx_encl_release);
+
+/**
+ * sgx_encl_get_index() - Convert a page descriptor to a page index
+ * @encl:	an enclave
+ * @page:	an enclave page
+ *
+ * Given an enclave page descriptor, convert it to a page index used to access
+ * backing storage. The backing page for SECS is located after the enclave
+ * pages.
+ */
+pgoff_t sgx_encl_get_index(struct sgx_encl *encl, struct sgx_encl_page *page)
+{
+	if (!PFN_DOWN(page->desc))
+		return PFN_DOWN(encl->size);
+
+	return PFN_DOWN(page->desc - encl->base);
+}
+EXPORT_SYMBOL_GPL(sgx_encl_get_index);
+
+/**
+ * sgx_encl_encl_get_backing_page() - Pin the backing page
+ * @encl:	an enclave
+ * @index:	page index
+ *
+ * Return: the pinned backing page
+ */
+struct page *sgx_encl_get_backing_page(struct sgx_encl *encl, pgoff_t index)
+{
+	struct inode *inode = encl->backing->f_path.dentry->d_inode;
+	struct address_space *mapping = inode->i_mapping;
+	gfp_t gfpmask = mapping_gfp_mask(mapping);
+
+	return shmem_read_mapping_page_gfp(mapping, index, gfpmask);
+}
+EXPORT_SYMBOL_GPL(sgx_encl_get_backing_page);
+
+/**
+ * sgx_encl_next_mm() - Iterate to the next mm
+ * @encl:	an enclave
+ * @mm:		an mm list entry
+ * @iter:	iterator status
+ *
+ * Return: the enclave mm or NULL
+ */
+struct sgx_encl_mm *sgx_encl_next_mm(struct sgx_encl *encl,
+				     struct sgx_encl_mm *mm, int *iter)
+{
+	struct list_head *entry;
+
+	WARN(!encl, "%s: encl is NULL", __func__);
+	WARN(!iter, "%s: iter is NULL", __func__);
+
+	spin_lock(&encl->mm_lock);
+
+	entry = mm ? mm->list.next : encl->mm_list.next;
+	WARN(!entry, "%s: entry is NULL", __func__);
+
+	if (entry == &encl->mm_list) {
+		mm = NULL;
+		*iter = SGX_ENCL_MM_ITER_DONE;
+		goto out;
+	}
+
+	mm = list_entry(entry, struct sgx_encl_mm, list);
+
+	if (!kref_get_unless_zero(&mm->refcount)) {
+		*iter = SGX_ENCL_MM_ITER_RESTART;
+		mm = NULL;
+		goto out;
+	}
+
+	if (!atomic_add_unless(&mm->mm->mm_count, 1, 0)) {
+		kref_put(&mm->refcount, sgx_encl_release_mm);
+		mm = NULL;
+		*iter = SGX_ENCL_MM_ITER_RESTART;
+		goto out;
+	}
+
+	*iter = SGX_ENCL_MM_ITER_NEXT;
+
+out:
+	spin_unlock(&encl->mm_lock);
+	return mm;
+}
+
+void sgx_encl_release_mm(struct kref *ref)
+{
+	struct sgx_encl_mm *mm =
+		container_of(ref, struct sgx_encl_mm, refcount);
+
+	spin_lock(&mm->encl->mm_lock);
+	list_del(&mm->list);
+	spin_unlock(&mm->encl->mm_lock);
+
+	kfree(mm);
+}
diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
new file mode 100644
index 000000000000..374ad3396684
--- /dev/null
+++ b/arch/x86/kernel/cpu/sgx/encl.h
@@ -0,0 +1,88 @@ 
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
+/**
+ * Copyright(c) 2016-19 Intel Corporation.
+ */
+#ifndef _X86_ENCL_H
+#define _X86_ENCL_H
+
+#include <linux/mmu_notifier.h>
+
+/**
+ * enum sgx_encl_page_desc - defines bits for an enclave page's descriptor
+ * %SGX_ENCL_PAGE_TCS:			The page is a TCS page.
+ * %SGX_ENCL_PAGE_ADDR_MASK:		Holds the virtual address of the page.
+ *
+ * The page address for SECS is zero and is used by the subsystem to recognize
+ * the SECS page.
+ */
+enum sgx_encl_page_desc {
+	SGX_ENCL_PAGE_TCS		= BIT(0),
+	/* Bits 11:3 are available when the page is not swapped. */
+	SGX_ENCL_PAGE_ADDR_MASK		= PAGE_MASK,
+};
+
+#define SGX_ENCL_PAGE_ADDR(encl_page) \
+	((encl_page)->desc & SGX_ENCL_PAGE_ADDR_MASK)
+#define SGX_ENCL_PAGE_VA_OFFSET(encl_page) \
+	((encl_page)->desc & SGX_ENCL_PAGE_VA_OFFSET_MASK)
+
+struct sgx_encl_page {
+	unsigned long desc;
+	struct sgx_epc_page *epc_page;
+	struct sgx_encl *encl;
+};
+
+enum sgx_encl_flags {
+	SGX_ENCL_INITIALIZED	= BIT(0),
+	SGX_ENCL_DEBUG		= BIT(1),
+	SGX_ENCL_SUSPEND	= BIT(2),
+	SGX_ENCL_DEAD		= BIT(3),
+};
+
+struct sgx_encl_mm {
+	struct sgx_encl *encl;
+	struct mm_struct *mm;
+	struct kref refcount;
+	struct list_head list;
+};
+
+struct sgx_encl {
+	unsigned int flags;
+	u64 secs_attributes;
+	u64 allowed_attributes;
+	unsigned int page_cnt;
+	unsigned int secs_child_cnt;
+	struct mutex lock;
+	struct list_head mm_list;
+	spinlock_t mm_lock;
+	struct file *backing;
+	struct kref refcount;
+	unsigned long base;
+	unsigned long size;
+	unsigned long ssaframesize;
+	struct radix_tree_root page_tree;
+	struct list_head add_page_reqs;
+	struct work_struct work;
+	struct sgx_encl_page secs;
+	struct notifier_block pm_notifier;
+};
+
+extern const struct vm_operations_struct sgx_vm_ops;
+
+enum sgx_encl_mm_iter {
+	SGX_ENCL_MM_ITER_DONE		= 0,
+	SGX_ENCL_MM_ITER_NEXT		= 1,
+	SGX_ENCL_MM_ITER_RESTART	= 2,
+};
+
+int sgx_encl_find(struct mm_struct *mm, unsigned long addr,
+		  struct vm_area_struct **vma);
+void sgx_encl_destroy(struct sgx_encl *encl);
+void sgx_encl_release(struct kref *ref);
+pgoff_t sgx_encl_get_index(struct sgx_encl *encl, struct sgx_encl_page *page);
+struct page *sgx_encl_get_backing_page(struct sgx_encl *encl, pgoff_t index);
+struct sgx_encl_mm *sgx_encl_next_mm(struct sgx_encl *encl,
+				     struct sgx_encl_mm *mm, int *iter);
+void sgx_encl_release_mm(struct kref *ref);
+
+#endif /* _X86_ENCL_H */
diff --git a/arch/x86/kernel/cpu/sgx/encls.c b/arch/x86/kernel/cpu/sgx/encls.c
index 5045f1365e07..698cc526bfbf 100644
--- a/arch/x86/kernel/cpu/sgx/encls.c
+++ b/arch/x86/kernel/cpu/sgx/encls.c
@@ -19,3 +19,4 @@  bool encls_failed(int ret)
 
 	return encls_faulted(ret) && ENCLS_TRAPNR(ret) != epcm_trapnr;
 }
+EXPORT_SYMBOL_GPL(encls_failed);
diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index e966f96837c7..d88dc3d1d4a7 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -14,6 +14,8 @@ 
 
 struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS];
 EXPORT_SYMBOL_GPL(sgx_epc_sections);
+bool sgx_enabled;
+EXPORT_SYMBOL_GPL(sgx_enabled);
 
 static int sgx_nr_epc_sections;
 
@@ -283,6 +285,7 @@  static __init int sgx_init(void)
 	if (ret)
 		return ret;
 
+	sgx_enabled = true;
 	return 0;
 }
 
diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h
index f90d02fbbbbd..2337b63ba487 100644
--- a/arch/x86/kernel/cpu/sgx/sgx.h
+++ b/arch/x86/kernel/cpu/sgx/sgx.h
@@ -34,6 +34,7 @@  struct sgx_epc_section {
 #define SGX_MAX_EPC_SECTIONS	8
 
 extern struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS];
+extern bool sgx_enabled;
 
 /**
  * enum sgx_epc_page_desc - bits and masks for an EPC page's descriptor