KVM: Rename CONFIG_KVM_PRIVATE_MEM to CONFIG_KVM_GUEST_MEMFD

Rename the Kconfig option CONFIG_KVM_PRIVATE_MEM to
CONFIG_KVM_GUEST_MEMFD. The original name implied that the feature only
supported "private" memory. However, CONFIG_KVM_PRIVATE_MEM enables
guest_memfd in general, which is not exclusively for private memory.
Subsequent patches in this series will add guest_memfd support for
non-CoCo VMs, whose memory is not private.

Renaming the Kconfig option to CONFIG_KVM_GUEST_MEMFD more accurately
reflects its broader scope as the main Kconfig option for all
guest_memfd-backed memory. This provides clearer semantics for the
option and avoids confusion as new features are introduced.

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: <20250729225455.670324-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Author: Fuad Tabba

arch/x86/include/asm/kvm_host.h

@@ -2276,7 +2276,7 @@ void kvm_configure_mmu(bool enable_tdp, int tdp_forced_root_level,
 		       int tdp_max_root_level, int tdp_huge_page_level);
 
 
-#ifdef CONFIG_KVM_PRIVATE_MEM
+#ifdef CONFIG_KVM_GUEST_MEMFD
 #define kvm_arch_has_private_mem(kvm) ((kvm)->arch.has_private_mem)
 #else
 #define kvm_arch_has_private_mem(kvm) false

include/linux/kvm_host.h

@@ -602,7 +602,7 @@ struct kvm_memory_slot {
 	short id;
 	u16 as_id;
 
-#ifdef CONFIG_KVM_PRIVATE_MEM
+#ifdef CONFIG_KVM_GUEST_MEMFD
 	struct {
 		/*
 		 * Writes protected by kvm->slots_lock.  Acquiring a
@@ -720,10 +720,10 @@ static inline int kvm_arch_vcpu_memslots_id(struct kvm_vcpu *vcpu)
 #endif
 
 /*
- * Arch code must define kvm_arch_has_private_mem if support for private memory
- * is enabled.
+ * Arch code must define kvm_arch_has_private_mem if support for guest_memfd is
+ * enabled.
  */
-#if !defined(kvm_arch_has_private_mem) && !IS_ENABLED(CONFIG_KVM_PRIVATE_MEM)
+#if !defined(kvm_arch_has_private_mem) && !IS_ENABLED(CONFIG_KVM_GUEST_MEMFD)
 static inline bool kvm_arch_has_private_mem(struct kvm *kvm)
 {
 	return false;
@@ -2505,7 +2505,7 @@ bool kvm_arch_post_set_memory_attributes(struct kvm *kvm,
 
 static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn)
 {
-	return IS_ENABLED(CONFIG_KVM_PRIVATE_MEM) &&
+	return IS_ENABLED(CONFIG_KVM_GUEST_MEMFD) &&
 	       kvm_get_memory_attributes(kvm, gfn) & KVM_MEMORY_ATTRIBUTE_PRIVATE;
 }
 #else
@@ -2515,7 +2515,7 @@ static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn)
 }
 #endif /* CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES */
 
-#ifdef CONFIG_KVM_PRIVATE_MEM
+#ifdef CONFIG_KVM_GUEST_MEMFD
 int kvm_gmem_get_pfn(struct kvm *kvm, struct kvm_memory_slot *slot,
 		     gfn_t gfn, kvm_pfn_t *pfn, struct page **page,
 		     int *max_order);
@@ -2528,7 +2528,7 @@ static inline int kvm_gmem_get_pfn(struct kvm *kvm,
 	KVM_BUG_ON(1, kvm);
 	return -EIO;
 }
-#endif /* CONFIG_KVM_PRIVATE_MEM */
+#endif /* CONFIG_KVM_GUEST_MEMFD */
 
 #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE
 int kvm_arch_gmem_prepare(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, int max_order);

virt/kvm/Kconfig

@@ -112,19 +112,19 @@ config KVM_GENERIC_MEMORY_ATTRIBUTES
        depends on KVM_GENERIC_MMU_NOTIFIER
        bool
 
-config KVM_PRIVATE_MEM
+config KVM_GUEST_MEMFD
        select XARRAY_MULTI
        bool
 
 config KVM_GENERIC_PRIVATE_MEM
        select KVM_GENERIC_MEMORY_ATTRIBUTES
-       select KVM_PRIVATE_MEM
+       select KVM_GUEST_MEMFD
        bool
 
 config HAVE_KVM_ARCH_GMEM_PREPARE
        bool
-       depends on KVM_PRIVATE_MEM
+       depends on KVM_GUEST_MEMFD
 
 config HAVE_KVM_ARCH_GMEM_INVALIDATE
        bool
-       depends on KVM_PRIVATE_MEM
+       depends on KVM_GUEST_MEMFD

virt/kvm/Makefile.kvm

@@ -12,4 +12,4 @@ kvm-$(CONFIG_KVM_ASYNC_PF) += $(KVM)/async_pf.o
 kvm-$(CONFIG_HAVE_KVM_IRQ_ROUTING) += $(KVM)/irqchip.o
 kvm-$(CONFIG_HAVE_KVM_DIRTY_RING) += $(KVM)/dirty_ring.o
 kvm-$(CONFIG_HAVE_KVM_PFNCACHE) += $(KVM)/pfncache.o
-kvm-$(CONFIG_KVM_PRIVATE_MEM) += $(KVM)/guest_memfd.o
+kvm-$(CONFIG_KVM_GUEST_MEMFD) += $(KVM)/guest_memfd.o

virt/kvm/kvm_main.c

@@ -4915,7 +4915,7 @@ static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 	case KVM_CAP_MEMORY_ATTRIBUTES:
 		return kvm_supported_mem_attributes(kvm);
 #endif
-#ifdef CONFIG_KVM_PRIVATE_MEM
+#ifdef CONFIG_KVM_GUEST_MEMFD
 	case KVM_CAP_GUEST_MEMFD:
 		return !kvm || kvm_arch_has_private_mem(kvm);
 #endif
@@ -5352,7 +5352,7 @@ static long kvm_vm_ioctl(struct file *filp,
 	case KVM_GET_STATS_FD:
 		r = kvm_vm_ioctl_get_stats_fd(kvm);
 		break;
-#ifdef CONFIG_KVM_PRIVATE_MEM
+#ifdef CONFIG_KVM_GUEST_MEMFD
 	case KVM_CREATE_GUEST_MEMFD: {
 		struct kvm_create_guest_memfd guest_memfd;
 

virt/kvm/kvm_mm.h

@@ -67,7 +67,7 @@ static inline void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm,
 }
 #endif /* HAVE_KVM_PFNCACHE */
 
-#ifdef CONFIG_KVM_PRIVATE_MEM
+#ifdef CONFIG_KVM_GUEST_MEMFD
 void kvm_gmem_init(struct module *module);
 int kvm_gmem_create(struct kvm *kvm, struct kvm_create_guest_memfd *args);
 int kvm_gmem_bind(struct kvm *kvm, struct kvm_memory_slot *slot,
@@ -91,6 +91,6 @@ static inline void kvm_gmem_unbind(struct kvm_memory_slot *slot)
 {
 	WARN_ON_ONCE(1);
 }
-#endif /* CONFIG_KVM_PRIVATE_MEM */
+#endif /* CONFIG_KVM_GUEST_MEMFD */
 
 #endif /* __KVM_MM_H__ */