@@ -1 +1 @@
-obj-y += main.o
+obj-y += main.o encls.o
new file mode 100644
@@ -0,0 +1,21 @@
+#include <asm/cpufeature.h>
+#include <asm/traps.h>
+#include "encls.h"
+#include "sgx.h"
+
+/**
+ * encls_failed() - Check if an ENCLS leaf function failed
+ * @ret: the return value of an ENCLS leaf function call
+ *
+ * Check if an ENCLS leaf function failed. This is a condition where the leaf
+ * function causes a fault that is not caused by an EPCM conflict.
+ *
+ * Return: true if there was a fault other than an EPCM conflict
+ */
+bool encls_failed(int ret)
+{
+ int epcm_trapnr = boot_cpu_has(X86_FEATURE_SGX2) ?
+ X86_TRAP_PF : X86_TRAP_GP;
+
+ return encls_faulted(ret) && ENCLS_TRAPNR(ret) != epcm_trapnr;
+}
new file mode 100644
@@ -0,0 +1,244 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
+#ifndef _X86_ENCLS_H
+#define _X86_ENCLS_H
+
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/rwsem.h>
+#include <linux/types.h>
+#include <asm/asm.h>
+#include "arch.h"
+
+/**
+ * ENCLS_FAULT_FLAG - flag signifying an ENCLS return code is a trapnr
+ *
+ * ENCLS has its own (positive value) error codes and also generates
+ * ENCLS specific #GP and #PF faults. And the ENCLS values get munged
+ * with system error codes as everything percolates back up the stack.
+ * Unfortunately (for us), we need to precisely identify each unique
+ * error code, e.g. the action taken if EWB fails varies based on the
+ * type of fault and on the exact SGX error code, i.e. we can't simply
+ * convert all faults to -EFAULT.
+ *
+ * To make all three error types coexist, we set bit 30 to identify an
+ * ENCLS fault. Bit 31 (technically bits N:31) is used to differentiate
+ * between positive (faults and SGX error codes) and negative (system
+ * error codes) values.
+ */
+#define ENCLS_FAULT_FLAG 0x40000000
+
+/**
+ * Retrieve the encoded trapnr from the specified return code.
+ */
+#define ENCLS_TRAPNR(r) ((r) & ~ENCLS_FAULT_FLAG)
+
+/* Issue a WARN() about an ENCLS leaf. */
+#define ENCLS_WARN(r, name) { \
+ do { \
+ int _r = (r); \
+ WARN(_r, "sgx: %s returned %d (0x%x)\n", (name), _r, \
+ _r); \
+ } while (0); \
+}
+
+/**
+ * encls_faulted() - Check if ENCLS leaf function faulted
+ * @ret: the return value of an ENCLS leaf function call
+ *
+ * Return: true if the fault flag is set
+ */
+static inline bool encls_faulted(int ret)
+{
+ return (ret & ENCLS_FAULT_FLAG) != 0;
+}
+
+/**
+ * encls_returned_code() - Check if an ENCLS leaf function returned a code
+ * @ret: the return value of an ENCLS leaf function call
+ *
+ * Check if an ENCLS leaf function returned an error or information code.
+ *
+ * Return: true if there was a fault other than an EPCM conflict
+ */
+static inline bool encls_returned_code(int ret)
+{
+ return !encls_faulted(ret) && ret;
+}
+
+bool encls_failed(int ret);
+
+/**
+ * __encls_ret_N - encode an ENCLS leaf that returns an error code in EAX
+ * @rax: leaf number
+ * @inputs: asm inputs for the leaf
+ *
+ * Emit assembly for an ENCLS leaf that returns an error code, e.g. EREMOVE.
+ * And because SGX isn't complex enough as it is, leafs that return an error
+ * code also modify flags.
+ *
+ * Return:
+ * 0 on success,
+ * SGX error code on failure
+ */
+#define __encls_ret_N(rax, inputs...) \
+ ({ \
+ int ret; \
+ asm volatile( \
+ "1: .byte 0x0f, 0x01, 0xcf;\n\t" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ "3: orl $"__stringify(ENCLS_FAULT_FLAG)",%%eax\n" \
+ " jmp 2b\n" \
+ ".previous\n" \
+ _ASM_EXTABLE_FAULT(1b, 3b) \
+ : "=a"(ret) \
+ : "a"(rax), inputs \
+ : "memory", "cc"); \
+ ret; \
+ })
+
+#define __encls_ret_1(rax, rcx) \
+ ({ \
+ __encls_ret_N(rax, "c"(rcx)); \
+ })
+
+#define __encls_ret_2(rax, rbx, rcx) \
+ ({ \
+ __encls_ret_N(rax, "b"(rbx), "c"(rcx)); \
+ })
+
+#define __encls_ret_3(rax, rbx, rcx, rdx) \
+ ({ \
+ __encls_ret_N(rax, "b"(rbx), "c"(rcx), "d"(rdx)); \
+ })
+
+/**
+ * __encls_N - encode an ENCLS leaf that doesn't return an error code
+ * @rax: leaf number
+ * @rbx_out: optional output variable
+ * @inputs: asm inputs for the leaf
+ *
+ * Emit assembly for an ENCLS leaf that does not return an error code,
+ * e.g. ECREATE. Leaves without error codes either succeed or fault.
+ * @rbx_out is an optional parameter for use by EDGBRD, which returns
+ * the the requested value in RBX.
+ *
+ * Return:
+ * 0 on success,
+ * trapnr with ENCLS_FAULT_FLAG set on fault
+ */
+#define __encls_N(rax, rbx_out, inputs...) \
+ ({ \
+ int ret; \
+ asm volatile( \
+ "1: .byte 0x0f, 0x01, 0xcf;\n\t" \
+ " xor %%eax,%%eax;\n" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ "3: orl $"__stringify(ENCLS_FAULT_FLAG)",%%eax\n" \
+ " jmp 2b\n" \
+ ".previous\n" \
+ _ASM_EXTABLE_FAULT(1b, 3b) \
+ : "=a"(ret), "=b"(rbx_out) \
+ : "a"(rax), inputs \
+ : "memory"); \
+ ret; \
+ })
+
+#define __encls_2(rax, rbx, rcx) \
+ ({ \
+ unsigned long ign_rbx_out; \
+ __encls_N(rax, ign_rbx_out, "b"(rbx), "c"(rcx)); \
+ })
+
+#define __encls_1_1(rax, data, rcx) \
+ ({ \
+ unsigned long rbx_out; \
+ int ret = __encls_N(rax, rbx_out, "c"(rcx)); \
+ if (!ret) \
+ data = rbx_out; \
+ ret; \
+ })
+
+static inline int __ecreate(struct sgx_pageinfo *pginfo, void *secs)
+{
+ return __encls_2(SGX_ECREATE, pginfo, secs);
+}
+
+static inline int __eextend(void *secs, void *addr)
+{
+ return __encls_2(SGX_EEXTEND, secs, addr);
+}
+
+static inline int __eadd(struct sgx_pageinfo *pginfo, void *addr)
+{
+ return __encls_2(SGX_EADD, pginfo, addr);
+}
+
+static inline int __einit(void *sigstruct, struct sgx_einittoken *einittoken,
+ void *secs)
+{
+ return __encls_ret_3(SGX_EINIT, sigstruct, secs, einittoken);
+}
+
+static inline int __eremove(void *addr)
+{
+ return __encls_ret_1(SGX_EREMOVE, addr);
+}
+
+static inline int __edbgwr(void *addr, unsigned long *data)
+{
+ return __encls_2(SGX_EDGBWR, *data, addr);
+}
+
+static inline int __edbgrd(void *addr, unsigned long *data)
+{
+ return __encls_1_1(SGX_EDGBRD, *data, addr);
+}
+
+static inline int __etrack(void *addr)
+{
+ return __encls_ret_1(SGX_ETRACK, addr);
+}
+
+static inline int __eldu(struct sgx_pageinfo *pginfo, void *addr,
+ void *va)
+{
+ return __encls_ret_3(SGX_ELDU, pginfo, addr, va);
+}
+
+static inline int __eblock(void *addr)
+{
+ return __encls_ret_1(SGX_EBLOCK, addr);
+}
+
+static inline int __epa(void *addr)
+{
+ unsigned long rbx = SGX_PAGE_TYPE_VA;
+
+ return __encls_2(SGX_EPA, rbx, addr);
+}
+
+static inline int __ewb(struct sgx_pageinfo *pginfo, void *addr,
+ void *va)
+{
+ return __encls_ret_3(SGX_EWB, pginfo, addr, va);
+}
+
+static inline int __eaug(struct sgx_pageinfo *pginfo, void *addr)
+{
+ return __encls_2(SGX_EAUG, pginfo, addr);
+}
+
+static inline int __emodpr(struct sgx_secinfo *secinfo, void *addr)
+{
+ return __encls_ret_2(SGX_EMODPR, secinfo, addr);
+}
+
+static inline int __emodt(struct sgx_secinfo *secinfo, void *addr)
+{
+ return __encls_ret_2(SGX_EMODT, secinfo, addr);
+}
+
+#endif /* _X86_ENCLS_H */