x86/cc: Move arch/x86/{kernel/cc_platform.c => coco/core.c}

Move cc_platform.c to arch/x86/coco/. The directory is going to be the
home space for code related to confidential computing.

Intel TDX code will land here. AMD SEV code will also eventually be
moved there.

No functional changes.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20220222185740.26228-3-kirill.shutemov@linux.intel.com

diff --git a/arch/x86/Kbuild b/arch/x86/Kbuild
index f384cb1a4f7a8ddca2f73e2cdf4b80bdb3445464..5a83da703e8766199f3123f0c915f8743a5e1847 100644 (file)
--- a/arch/x86/Kbuild
+++ b/arch/x86/Kbuild
@@ -1,4 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += coco/
+
 obj-y += entry/
 
 obj-$(CONFIG_PERF_EVENTS) += events/

diff --git a/arch/x86/coco/Makefile b/arch/x86/coco/Makefile
new file mode 100644 (file)
index 0000000..c1ead00
--- /dev/null
+++ b/arch/x86/coco/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS_REMOVE_core.o   = -pg
+KASAN_SANITIZE_core.o  := n
+CFLAGS_core.o          += -fno-stack-protector
+
+obj-y += core.o

diff --git a/arch/x86/coco/core.c b/arch/x86/coco/core.c
new file mode 100644 (file)
index 0000000..6a6ffcd
--- /dev/null
+++ b/arch/x86/coco/core.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Confidential Computing Platform Capability checks
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#include <linux/export.h>
+#include <linux/cc_platform.h>
+#include <linux/mem_encrypt.h>
+
+#include <asm/mshyperv.h>
+#include <asm/processor.h>
+
+static bool __maybe_unused intel_cc_platform_has(enum cc_attr attr)
+{
+#ifdef CONFIG_INTEL_TDX_GUEST
+       return false;
+#else
+       return false;
+#endif
+}
+
+/*
+ * SME and SEV are very similar but they are not the same, so there are
+ * times that the kernel will need to distinguish between SME and SEV. The
+ * cc_platform_has() function is used for this.  When a distinction isn't
+ * needed, the CC_ATTR_MEM_ENCRYPT attribute can be used.
+ *
+ * The trampoline code is a good example for this requirement.  Before
+ * paging is activated, SME will access all memory as decrypted, but SEV
+ * will access all memory as encrypted.  So, when APs are being brought
+ * up under SME the trampoline area cannot be encrypted, whereas under SEV
+ * the trampoline area must be encrypted.
+ */
+static bool amd_cc_platform_has(enum cc_attr attr)
+{
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+       switch (attr) {
+       case CC_ATTR_MEM_ENCRYPT:
+               return sme_me_mask;
+
+       case CC_ATTR_HOST_MEM_ENCRYPT:
+               return sme_me_mask && !(sev_status & MSR_AMD64_SEV_ENABLED);
+
+       case CC_ATTR_GUEST_MEM_ENCRYPT:
+               return sev_status & MSR_AMD64_SEV_ENABLED;
+
+       case CC_ATTR_GUEST_STATE_ENCRYPT:
+               return sev_status & MSR_AMD64_SEV_ES_ENABLED;
+
+       /*
+        * With SEV, the rep string I/O instructions need to be unrolled
+        * but SEV-ES supports them through the #VC handler.
+        */
+       case CC_ATTR_GUEST_UNROLL_STRING_IO:
+               return (sev_status & MSR_AMD64_SEV_ENABLED) &&
+                       !(sev_status & MSR_AMD64_SEV_ES_ENABLED);
+
+       default:
+               return false;
+       }
+#else
+       return false;
+#endif
+}
+
+static bool hyperv_cc_platform_has(enum cc_attr attr)
+{
+       return attr == CC_ATTR_GUEST_MEM_ENCRYPT;
+}
+
+bool cc_platform_has(enum cc_attr attr)
+{
+       if (sme_me_mask)
+               return amd_cc_platform_has(attr);
+
+       if (hv_is_isolation_supported())
+               return hyperv_cc_platform_has(attr);
+
+       return false;
+}
+EXPORT_SYMBOL_GPL(cc_platform_has);

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 6aef9ee28a3940dbf6754cd990df7f61ee4e7798..6462e3dd98f49ac88911f880828af0a8a7e7402c 100644 (file)
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -21,7 +21,6 @@ CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 CFLAGS_REMOVE_head64.o = -pg
 CFLAGS_REMOVE_sev.o = -pg
-CFLAGS_REMOVE_cc_platform.o = -pg
 endif
 
 KASAN_SANITIZE_head$(BITS).o                           := n
@@ -30,7 +29,6 @@ KASAN_SANITIZE_dumpstack_$(BITS).o                    := n
 KASAN_SANITIZE_stacktrace.o                            := n
 KASAN_SANITIZE_paravirt.o                              := n
 KASAN_SANITIZE_sev.o                                   := n
-KASAN_SANITIZE_cc_platform.o                           := n
 
 # With some compiler versions the generated code results in boot hangs, caused
 # by several compilation units. To be safe, disable all instrumentation.
@@ -49,7 +47,6 @@ endif
 KCOV_INSTRUMENT                := n
 
 CFLAGS_head$(BITS).o   += -fno-stack-protector
-CFLAGS_cc_platform.o   += -fno-stack-protector
 
 CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace
 
@@ -151,8 +148,6 @@ obj-$(CONFIG_UNWINDER_GUESS)                += unwind_guess.o
 
 obj-$(CONFIG_AMD_MEM_ENCRYPT)          += sev.o
 
-obj-$(CONFIG_ARCH_HAS_CC_PLATFORM)     += cc_platform.o
-
 ###
 # 64 bit specific files
 ifeq ($(CONFIG_X86_64),y)

diff --git a/arch/x86/kernel/cc_platform.c b/arch/x86/kernel/cc_platform.c
deleted file mode 100644 (file)
index 6a6ffcd..0000000
--- a/arch/x86/kernel/cc_platform.c
+++ /dev/null
@@ -1,85 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Confidential Computing Platform Capability checks
- *
- * Copyright (C) 2021 Advanced Micro Devices, Inc.
- *
- * Author: Tom Lendacky <thomas.lendacky@amd.com>
- */
-
-#include <linux/export.h>
-#include <linux/cc_platform.h>
-#include <linux/mem_encrypt.h>
-
-#include <asm/mshyperv.h>
-#include <asm/processor.h>
-
-static bool __maybe_unused intel_cc_platform_has(enum cc_attr attr)
-{
-#ifdef CONFIG_INTEL_TDX_GUEST
-       return false;
-#else
-       return false;
-#endif
-}
-
-/*
- * SME and SEV are very similar but they are not the same, so there are
- * times that the kernel will need to distinguish between SME and SEV. The
- * cc_platform_has() function is used for this.  When a distinction isn't
- * needed, the CC_ATTR_MEM_ENCRYPT attribute can be used.
- *
- * The trampoline code is a good example for this requirement.  Before
- * paging is activated, SME will access all memory as decrypted, but SEV
- * will access all memory as encrypted.  So, when APs are being brought
- * up under SME the trampoline area cannot be encrypted, whereas under SEV
- * the trampoline area must be encrypted.
- */
-static bool amd_cc_platform_has(enum cc_attr attr)
-{
-#ifdef CONFIG_AMD_MEM_ENCRYPT
-       switch (attr) {
-       case CC_ATTR_MEM_ENCRYPT:
-               return sme_me_mask;
-
-       case CC_ATTR_HOST_MEM_ENCRYPT:
-               return sme_me_mask && !(sev_status & MSR_AMD64_SEV_ENABLED);
-
-       case CC_ATTR_GUEST_MEM_ENCRYPT:
-               return sev_status & MSR_AMD64_SEV_ENABLED;
-
-       case CC_ATTR_GUEST_STATE_ENCRYPT:
-               return sev_status & MSR_AMD64_SEV_ES_ENABLED;
-
-       /*
-        * With SEV, the rep string I/O instructions need to be unrolled
-        * but SEV-ES supports them through the #VC handler.
-        */
-       case CC_ATTR_GUEST_UNROLL_STRING_IO:
-               return (sev_status & MSR_AMD64_SEV_ENABLED) &&
-                       !(sev_status & MSR_AMD64_SEV_ES_ENABLED);
-
-       default:
-               return false;
-       }
-#else
-       return false;
-#endif
-}
-
-static bool hyperv_cc_platform_has(enum cc_attr attr)
-{
-       return attr == CC_ATTR_GUEST_MEM_ENCRYPT;
-}
-
-bool cc_platform_has(enum cc_attr attr)
-{
-       if (sme_me_mask)
-               return amd_cc_platform_has(attr);
-
-       if (hv_is_isolation_supported())
-               return hyperv_cc_platform_has(attr);
-
-       return false;
-}
-EXPORT_SYMBOL_GPL(cc_platform_has);