KVM: arm64: Move vcpu PC/Exception flags to the input flag set

The PC update flags (which also deal with exception injection)
is one of the most complicated use of the flag we have. Make it
more fool prof by:

- moving it over to the new accessors and assign it to the
  input flag set

- turn the combination of generic ELx flags with another flag
  indicating the target EL itself into an explicit set of
  flags for each EL and vector combination

- add a new accessor to pend the exception

This is otherwise a pretty straightformward conversion.

Reviewed-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

1 files changed, 34 insertions, 24 deletions

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 66a08b0e12a8..db42b4c06449 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -474,6 +474,40 @@ struct kvm_vcpu_arch {
 /* PTRAUTH exposed to guest */
 #define GUEST_HAS_PTRAUTH	__vcpu_single_flag(cflags, BIT(2))
 
+/* Exception pending */
+#define PENDING_EXCEPTION	__vcpu_single_flag(iflags, BIT(0))
+/*
+ * PC increment. Overlaps with EXCEPT_MASK on purpose so that it can't
+ * be set together with an exception...
+ */
+#define INCREMENT_PC		__vcpu_single_flag(iflags, BIT(1))
+/* Target EL/MODE (not a single flag, but let's abuse the macro) */
+#define EXCEPT_MASK		__vcpu_single_flag(iflags, GENMASK(3, 1))
+
+/* Helpers to encode exceptions with minimum fuss */
+#define __EXCEPT_MASK_VAL	unpack_vcpu_flag(EXCEPT_MASK)
+#define __EXCEPT_SHIFT		__builtin_ctzl(__EXCEPT_MASK_VAL)
+#define __vcpu_except_flags(_f)	iflags, (_f << __EXCEPT_SHIFT), __EXCEPT_MASK_VAL
+
+/*
+ * When PENDING_EXCEPTION is set, EXCEPT_MASK can take the following
+ * values:
+ *
+ * For AArch32 EL1:
+ */
+#define EXCEPT_AA32_UND		__vcpu_except_flags(0)
+#define EXCEPT_AA32_IABT	__vcpu_except_flags(1)
+#define EXCEPT_AA32_DABT	__vcpu_except_flags(2)
+/* For AArch64: */
+#define EXCEPT_AA64_EL1_SYNC	__vcpu_except_flags(0)
+#define EXCEPT_AA64_EL1_IRQ	__vcpu_except_flags(1)
+#define EXCEPT_AA64_EL1_FIQ	__vcpu_except_flags(2)
+#define EXCEPT_AA64_EL1_SERR	__vcpu_except_flags(3)
+/* For AArch64 with NV (one day): */
+#define EXCEPT_AA64_EL2_SYNC	__vcpu_except_flags(4)
+#define EXCEPT_AA64_EL2_IRQ	__vcpu_except_flags(5)
+#define EXCEPT_AA64_EL2_FIQ	__vcpu_except_flags(6)
+#define EXCEPT_AA64_EL2_SERR	__vcpu_except_flags(7)
 
 /* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */
 #define vcpu_sve_pffr(vcpu) (kern_hyp_va((vcpu)->arch.sve_state) +	\
@@ -498,30 +532,6 @@ struct kvm_vcpu_arch {
 /* vcpu_arch flags field values: */
 #define KVM_ARM64_DEBUG_DIRTY		(1 << 0)
 #define KVM_ARM64_HOST_SVE_ENABLED	(1 << 4) /* SVE enabled for EL0 */
-#define KVM_ARM64_PENDING_EXCEPTION	(1 << 8) /* Exception pending */
-/*
- * Overlaps with KVM_ARM64_EXCEPT_MASK on purpose so that it can't be
- * set together with an exception...
- */
-#define KVM_ARM64_INCREMENT_PC		(1 << 9) /* Increment PC */
-#define KVM_ARM64_EXCEPT_MASK		(7 << 9) /* Target EL/MODE */
-/*
- * When KVM_ARM64_PENDING_EXCEPTION is set, KVM_ARM64_EXCEPT_MASK can
- * take the following values:
- *
- * For AArch32 EL1:
- */
-#define KVM_ARM64_EXCEPT_AA32_UND	(0 << 9)
-#define KVM_ARM64_EXCEPT_AA32_IABT	(1 << 9)
-#define KVM_ARM64_EXCEPT_AA32_DABT	(2 << 9)
-/* For AArch64: */
-#define KVM_ARM64_EXCEPT_AA64_ELx_SYNC	(0 << 9)
-#define KVM_ARM64_EXCEPT_AA64_ELx_IRQ	(1 << 9)
-#define KVM_ARM64_EXCEPT_AA64_ELx_FIQ	(2 << 9)
-#define KVM_ARM64_EXCEPT_AA64_ELx_SERR	(3 << 9)
-#define KVM_ARM64_EXCEPT_AA64_EL1	(0 << 11)
-#define KVM_ARM64_EXCEPT_AA64_EL2	(1 << 11)
-
 #define KVM_ARM64_DEBUG_STATE_SAVE_SPE	(1 << 12) /* Save SPE context if active  */
 #define KVM_ARM64_DEBUG_STATE_SAVE_TRBE	(1 << 13) /* Save TRBE context if active  */
 #define KVM_ARM64_ON_UNSUPPORTED_CPU	(1 << 15) /* Physical CPU not in supported_cpus */