KVM: Rename kvm_slot_can_be_private() to kvm_slot_has_gmem()

Rename kvm_slot_can_be_private() to kvm_slot_has_gmem() to improve
clarity and accurately reflect its purpose.

The function kvm_slot_can_be_private() was previously used to check if a
given kvm_memory_slot is backed by guest_memfd. However, its name
implied that the memory in such a slot was exclusively "private".

As guest_memfd support expands to include non-private memory (e.g.,
shared host mappings), it's important to remove this association. The
new name, kvm_slot_has_gmem(), states that the slot is backed by
guest_memfd without making assumptions about the memory's privacy
attributes.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Co-developed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250729225455.670324-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Author: Fuad Tabba

arch/x86/kvm/mmu/mmu.c

@@ -3312,7 +3312,7 @@ static int __kvm_mmu_max_mapping_level(struct kvm *kvm,
 int kvm_mmu_max_mapping_level(struct kvm *kvm,
 			      const struct kvm_memory_slot *slot, gfn_t gfn)
 {
-	bool is_private = kvm_slot_can_be_private(slot) &&
+	bool is_private = kvm_slot_has_gmem(slot) &&
 			  kvm_mem_is_private(kvm, gfn);
 
 	return __kvm_mmu_max_mapping_level(kvm, slot, gfn, PG_LEVEL_NUM, is_private);
@@ -4551,7 +4551,7 @@ static int kvm_mmu_faultin_pfn_private(struct kvm_vcpu *vcpu,
 {
 	int max_order, r;
 
-	if (!kvm_slot_can_be_private(fault->slot)) {
+	if (!kvm_slot_has_gmem(fault->slot)) {
 		kvm_mmu_prepare_memory_fault_exit(vcpu, fault);
 		return -EFAULT;
 	}

arch/x86/kvm/svm/sev.c

@@ -2361,7 +2361,7 @@ static int snp_launch_update(struct kvm *kvm, struct kvm_sev_cmd *argp)
 	mutex_lock(&kvm->slots_lock);
 
 	memslot = gfn_to_memslot(kvm, params.gfn_start);
-	if (!kvm_slot_can_be_private(memslot)) {
+	if (!kvm_slot_has_gmem(memslot)) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -4715,7 +4715,7 @@ void sev_handle_rmp_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code)
 	}
 
 	slot = gfn_to_memslot(kvm, gfn);
-	if (!kvm_slot_can_be_private(slot)) {
+	if (!kvm_slot_has_gmem(slot)) {
 		pr_warn_ratelimited("SEV: Unexpected RMP fault, non-private slot for GPA 0x%llx\n",
 				    gpa);
 		return;

include/linux/kvm_host.h

@@ -615,7 +615,7 @@ struct kvm_memory_slot {
 #endif
 };
 
-static inline bool kvm_slot_can_be_private(const struct kvm_memory_slot *slot)
+static inline bool kvm_slot_has_gmem(const struct kvm_memory_slot *slot)
 {
 	return slot && (slot->flags & KVM_MEM_GUEST_MEMFD);
 }

virt/kvm/guest_memfd.c

@@ -643,7 +643,7 @@ long kvm_gmem_populate(struct kvm *kvm, gfn_t start_gfn, void __user *src, long
 		return -EINVAL;
 
 	slot = gfn_to_memslot(kvm, start_gfn);
-	if (!kvm_slot_can_be_private(slot))
+	if (!kvm_slot_has_gmem(slot))
 		return -EINVAL;
 
 	file = kvm_gmem_get_file(slot);