[RFC,v3,10/19] KVM: x86: nSVM: implement AVIC's physid/logid table access helpers

Commit Message

Maxim Levitsky April 27, 2022, 8:03 p.m. UTC

This implements a few helpers that help manipulate the AVIC's
physical and logical id table entries.

Signed-off-by: Maxim Levitsky <[e-mail]>
---
 arch/x86/kvm/svm/svm.h | 45 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

Patch

diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 6fcb164a6ee4a..dfca4c06e2071 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -628,6 +628,51 @@  void avic_vcpu_unblocking(struct kvm_vcpu *vcpu);
 void avic_ring_doorbell(struct kvm_vcpu *vcpu);
 unsigned long avic_vcpu_get_apicv_inhibit_reasons(struct kvm_vcpu *vcpu);
 
+#define INVALID_BACKING_PAGE	(~(u64)0)
+
+static inline u64 physid_entry_get_backing_table(u64 entry)
+{
+	if (!(entry & AVIC_PHYSICAL_ID_ENTRY_VALID_MASK))
+		return INVALID_BACKING_PAGE;
+	return entry & AVIC_PHYSICAL_ID_ENTRY_BACKING_PAGE_MASK;
+}
+
+static inline int physid_entry_get_apicid(u64 entry)
+{
+	if (!(entry & AVIC_PHYSICAL_ID_ENTRY_VALID_MASK))
+		return -1;
+	if (!(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK))
+		return -1;
+
+	return entry & AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK;
+}
+
+static inline int logid_get_physid(u64 entry)
+{
+	if (!(entry & AVIC_LOGICAL_ID_ENTRY_VALID_BIT))
+		return -1;
+	return entry & AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK;
+}
+
+static inline void physid_entry_set_backing_table(u64 *entry, u64 value)
+{
+	*entry &= ~AVIC_PHYSICAL_ID_ENTRY_BACKING_PAGE_MASK;
+	*entry |= (AVIC_PHYSICAL_ID_ENTRY_VALID_MASK | value);
+}
+
+static inline void physid_entry_set_apicid(u64 *entry, int value)
+{
+	WARN_ON(!(*entry & AVIC_PHYSICAL_ID_ENTRY_VALID_MASK));
+
+	*entry &= ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK;
+
+	if (value == -1)
+		*entry &= ~(AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK);
+	else
+		*entry |= (AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK | value);
+}
+
+
 /* sev.c */
 
 #define GHCB_VERSION_MAX	1ULL