[RFC PATCH v2 11/26] x86/sgx: Add encls_faulted() helper

Kai Huang
2021-01-18T03:29:12Z

From: Sean Christopherson <sean.j.christopherson@intel.com>

Add a helper to extract the fault indicator from an encoded ENCLS return
value. SGX virtualization will also need to detect ENCLS faults.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Kai Huang <kai.huang@intel.com>
---
arch/x86/kernel/cpu/sgx/encls.h | 14 +++++++++++++-
arch/x86/kernel/cpu/sgx/ioctl.c | 2 +-
2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/encls.h b/arch/x86/kernel/cpu/sgx/encls.h
index be5c49689980..55919a2b01b0 100644
--- a/arch/x86/kernel/cpu/sgx/encls.h
+++ b/arch/x86/kernel/cpu/sgx/encls.h
@@ -40,6 +40,18 @@
} while (0); \
}

+/*
+ * encls_faulted() - Check if an ENCLS leaf faulted given an error code
+ * @ret the return value of an ENCLS leaf function call
+ *
+ * Return:
+ * %true if @ret indicates a fault, %false otherwise
+ */
+static inline bool encls_faulted(int ret)
+{
+ return ret & ENCLS_FAULT_FLAG;
+}
+
/**
* encls_failed() - Check if an ENCLS function failed
* @ret: the return value of an ENCLS function call
@@ -50,7 +62,7 @@
*/
static inline bool encls_failed(int ret)
{
- if (ret & ENCLS_FAULT_FLAG)
+ if (encls_faulted(ret))
return ENCLS_TRAPNR(ret) != X86_TRAP_PF;

return !!ret;
diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index 90a5caf76939..e5977752c7be 100644
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -568,7 +568,7 @@ static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct,
}
}

- if (ret & ENCLS_FAULT_FLAG) {
+ if (encls_faulted(ret)) {
if (encls_failed(ret))
ENCLS_WARN(ret, "EINIT");

--
2.29.2