[PATCH 59/60] kvm: svm: Implement max_planes x86 operation

["Jörg Rödel" <joro@8bytes.org>]

From: Tom Lendacky <thomas.lendacky@amd.com>

Report the number of VMPL levels supported by SEV-SNP guests.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Co-developed-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kvm/svm/sev.c | 14 ++++++++++++--
 arch/x86/kvm/svm/svm.c | 12 +++++++++++-
 arch/x86/kvm/svm/svm.h |  3 +++
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index b67566fcb69e..528c8bd3e8fc 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -114,6 +114,7 @@ static unsigned long sev_me_mask;
 static unsigned int nr_asids;
 static unsigned long *sev_asid_bitmap;
 static unsigned long *sev_reclaim_asid_bitmap;
+static unsigned int vmpl_levels;
 
 static __always_inline void kvm_lockdep_assert_sev_lock_held(struct kvm *kvm)
 {
@@ -3103,6 +3104,9 @@ void __init sev_hardware_setup(void)
 	/* Set encryption bit location for SEV-ES guests */
 	sev_enc_bit = ebx & 0x3f;
 
+	/* Get the number of supported VMPL levels */
+	vmpl_levels = (ebx >> 12) & 0xf;
+
 	/* Maximum number of encrypted guests supported simultaneously */
 	max_sev_asid = ecx;
 	if (!max_sev_asid)
@@ -3217,9 +3221,10 @@ void __init sev_hardware_setup(void)
 										"disabled",
 			min_sev_es_asid, max_sev_es_asid);
 	if (boot_cpu_has(X86_FEATURE_SEV_SNP))
-		pr_info("SEV-SNP %s (ASIDs %u - %u)\n",
+		pr_info("SEV-SNP %s (ASIDs %u - %u), VMPL Levels %u\n",
 			str_enabled_disabled(sev_snp_supported),
-			min_snp_asid, max_snp_asid);
+			min_snp_asid, max_snp_asid,
+			vmpl_levels);
 
 	sev_enabled = sev_supported;
 	sev_es_enabled = sev_es_supported;
@@ -5852,3 +5857,8 @@ bool sev_snp_blocked(enum inject_type type, struct kvm_vcpu *vcpu)
 
 	return blocked;
 }
+
+int sev_snp_max_planes(struct kvm *kvm)
+{
+	return vmpl_levels;
+}
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 2ae82dc058c9..705063c7f0f0 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5321,6 +5321,16 @@ static void svm_free_plane(struct kvm_plane *plane)
 	kfree(svm_plane);
 }
 
+static unsigned svm_max_planes(struct kvm *kvm)
+{
+#ifdef CONFIG_KVM_AMD_SEV
+	if (____sev_snp_guest(kvm))
+		return sev_snp_max_planes(kvm);
+#endif
+
+	return kvm_x86_default_max_planes(kvm);
+}
+
 struct kvm_x86_ops svm_x86_ops __initdata = {
 	.name = KBUILD_MODNAME,
 
@@ -5465,7 +5475,7 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
 
 	.alloc_plane = svm_alloc_plane,
 	.free_plane = svm_free_plane,
-	.max_planes = kvm_x86_default_max_planes,
+	.max_planes = svm_max_planes,
 };
 
 /*
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 7e860f2abafb..7aba2cceb44d 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -1008,6 +1008,8 @@ static inline bool sev_snp_is_rinj_active(struct kvm_vcpu *vcpu)
 	return is_sev_snp_guest(vcpu) &&
 		(sev->vmsa_features & SVM_SEV_FEAT_RESTRICTED_INJECTION);
 };
+int sev_nr_vcpu_planes(struct kvm *kvm);
+int sev_snp_max_planes(struct kvm *kvm);
 #else
 static inline struct page *snp_safe_alloc_page_node(int node, gfp_t gfp)
 {
@@ -1051,6 +1053,7 @@ static inline bool sev_snp_inject(enum inject_type type, struct kvm_vcpu *vcpu)
 static inline void sev_snp_cancel_injection(struct kvm_vcpu *vcpu) {}
 static inline bool sev_snp_blocked(enum inject_type type, struct kvm_vcpu *vcpu) { return false; }
 static inline bool sev_snp_is_rinj_active(struct kvm_vcpu *vcpu) { return false; }
+static inline unsigned sev_snp_max_planes(struct kvm *kvm) { return 1; }
 #endif
 
 /* vmenter.S */
-- 
2.53.0