powerpc/security: Add a helper to query stf_barrier type
Add a helper to return the stf_barrier type for the current processor.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3bd5d7f96ea1547991ac2ce3137dc2b220bae285.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index 792eefa..27574f2 100644
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -39,6 +39,11 @@
return !!(powerpc_security_features & feature);
}
+#ifdef CONFIG_PPC_BOOK3S_64
+enum stf_barrier_type stf_barrier_type_get(void);
+#else
+static inline enum stf_barrier_type stf_barrier_type_get(void) { return STF_BARRIER_NONE; }
+#endif
// Features indicating support for Spectre/Meltdown mitigations
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 1a99849..15fb5ea 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -263,6 +263,11 @@
early_param("no_stf_barrier", handle_no_stf_barrier);
+enum stf_barrier_type stf_barrier_type_get(void)
+{
+ return stf_enabled_flush_types;
+}
+
/* This is the generic flag used by other architectures */
static int __init handle_ssbd(char *p)
{
