[PATCH RFC v7 05/64] KVM: x86: Add 'update_mem_attr' x86 op

[Michael Roth]

This callback will handle any platform-specific handling needed for
converting pages between shared/private.

Signed-off-by: Michael Roth <michael.roth@xxxxxxx>
---
 arch/x86/include/asm/kvm-x86-ops.h |  1 +
 arch/x86/include/asm/kvm_host.h    |  2 ++
 arch/x86/kvm/mmu/mmu.c             | 10 ++++++++--
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index efae987cdce0..52f94a0ba5e9 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -133,6 +133,7 @@ KVM_X86_OP(vcpu_deliver_sipi_vector)
 KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons);
 KVM_X86_OP_OPTIONAL_RET0(private_mem_enabled);
 KVM_X86_OP_OPTIONAL_RET0(fault_is_private);
+KVM_X86_OP_OPTIONAL_RET0(update_mem_attr)
 
 #undef KVM_X86_OP
 #undef KVM_X86_OP_OPTIONAL
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 92539708f062..13802389f0f9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1637,6 +1637,8 @@ struct kvm_x86_ops {
 			     int root_level);
 	int (*private_mem_enabled)(struct kvm *kvm);
 	int (*fault_is_private)(struct kvm *kvm, gpa_t gpa, u64 error_code, bool *private_fault);
+	int (*update_mem_attr)(struct kvm_memory_slot *slot, unsigned int attr,
+			       gfn_t start, gfn_t end);
 
 	bool (*has_wbinvd_exit)(void);
 
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 61a7c221b966..a0c41d391547 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -7130,7 +7130,7 @@ static void kvm_update_lpage_private_shared_mixed(struct kvm *kvm,
 {
 	unsigned long pages, mask;
 	gfn_t gfn, gfn_end, first, last;
-	int level;
+	int level, ret;
 	bool mixed;
 
 	/*
@@ -7153,7 +7153,7 @@ static void kvm_update_lpage_private_shared_mixed(struct kvm *kvm,
 		linfo_set_mixed(gfn, slot, level, mixed);
 
 		if (first == last)
-			return;
+			goto out;
 
 		for (gfn = first + pages; gfn < last; gfn += pages)
 			linfo_set_mixed(gfn, slot, level, false);
@@ -7166,6 +7166,12 @@ static void kvm_update_lpage_private_shared_mixed(struct kvm *kvm,
 		mixed = mem_attrs_mixed(kvm, slot, level, attrs, gfn, gfn_end);
 		linfo_set_mixed(gfn, slot, level, mixed);
 	}
+
+out:
+	ret = static_call(kvm_x86_update_mem_attr)(slot, attrs, start, end);
+	if (ret)
+		pr_warn_ratelimited("Failed to update GFN range 0x%llx-0x%llx with attributes 0x%lx. Ret: %d\n",
+				    start, end, attrs, ret);
 }
 
 void kvm_arch_set_memory_attributes(struct kvm *kvm,
-- 
2.25.1