arm64 Realms, powerpc secure guests and s390 protected virtualization
guests currently report CC_ATTR_MEM_ENCRYPT, but not
CC_ATTR_GUEST_MEM_ENCRYPT.

These environments are all secure guest configurations. Their
force_dma_unencrypted() implementations also treat the same secure guest
state as requiring unencrypted DMA. Report CC_ATTR_GUEST_MEM_ENCRYPT for
the same condition so generic confidential-computing code can distinguish
guest memory encryption from host memory encryption instead of relying only
on CC_ATTR_MEM_ENCRYPT.

Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
---
 arch/arm64/kernel/rsi.c                      | 1 +
 arch/powerpc/platforms/pseries/cc_platform.c | 1 +
 arch/s390/mm/init.c                          | 1 +
 3 files changed, 3 insertions(+)

diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c
index 92160f2e57ff..207e36db1e7a 100644
--- a/arch/arm64/kernel/rsi.c
+++ b/arch/arm64/kernel/rsi.c

@@ -27,6 +27,7 @@ bool cc_platform_has(enum cc_attr attr)
 {
 	switch (attr) {
 	case CC_ATTR_MEM_ENCRYPT:
+	case CC_ATTR_GUEST_MEM_ENCRYPT:
 		return is_realm_world();
 	default:
 		return false;

diff --git a/arch/powerpc/platforms/pseries/cc_platform.c b/arch/powerpc/platforms/pseries/cc_platform.c
index e8021af83a19..46e110a5a717 100644
--- a/arch/powerpc/platforms/pseries/cc_platform.c
+++ b/arch/powerpc/platforms/pseries/cc_platform.c

@@ -17,6 +17,7 @@ bool cc_platform_has(enum cc_attr attr)
 {
 	switch (attr) {
 	case CC_ATTR_MEM_ENCRYPT:
+	case CC_ATTR_GUEST_MEM_ENCRYPT:
 		return is_secure_guest();
 
 	default:

diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index c29326c44af0..6b1c5a4fa9ce 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c

@@ -148,6 +148,7 @@ bool cc_platform_has(enum cc_attr attr)
 {
 	switch (attr) {
 	case CC_ATTR_MEM_ENCRYPT:
+	case CC_ATTR_GUEST_MEM_ENCRYPT:
 		return is_prot_virt_guest();
 
 	default:

-- 
2.43.0