From 2131c4f763d2e4cbbe5c227a406488c38e23f806 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 23 Jul 2026 14:08:09 -0700 Subject: [PATCH] KVM: guest_memfd: Rename prepare() hook and Kconfig to make_private() / CONVERT Rework guest_memfd's prepare() hook into a more accurate make_private(), and rework its Kconfig from PREPARE to a more generic CONVERT. This will allow x86 to share (pun intended) a kvm_x86_ops.gmem_make_shared() hook between the "convert to shared" and "reclaim" flows, which are one and the same for SNP. No functional change intended. Reviewed-by: Ackerley Tng Reviewed-by: Fuad Tabba Link: https://patch.msgid.link/20260723210811.72720-8-seanjc@google.com Signed-off-by: Sean Christopherson --- arch/x86/include/asm/kvm-x86-ops.h | 4 ++-- arch/x86/include/asm/kvm_host.h | 4 ++-- arch/x86/kvm/Kconfig | 2 +- arch/x86/kvm/svm/sev.c | 2 +- arch/x86/kvm/svm/svm.c | 2 +- arch/x86/kvm/svm/svm.h | 2 +- arch/x86/kvm/x86.c | 6 +++--- include/linux/kvm_host.h | 5 +++-- virt/kvm/Kconfig | 2 +- virt/kvm/guest_memfd.c | 4 ++-- 10 files changed, 17 insertions(+), 16 deletions(-) diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index 210cb95d0a0b..a4d872ddef9d 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -146,8 +146,8 @@ KVM_X86_OP(vcpu_deliver_sipi_vector) KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons); KVM_X86_OP_OPTIONAL(get_untagged_addr) KVM_X86_OP_OPTIONAL(alloc_apic_backing_page) -#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE -KVM_X86_OP_OPTIONAL_RET0(gmem_prepare) +#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT +KVM_X86_OP_OPTIONAL_RET0(gmem_make_private) #endif #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM KVM_X86_OP_OPTIONAL(gmem_make_shared) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 693be16abd95..ae9a229c6b11 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1903,8 +1903,8 @@ struct kvm_x86_ops { gva_t (*get_untagged_addr)(struct kvm_vcpu *vcpu, gva_t gva, unsigned int flags); void *(*alloc_apic_backing_page)(struct kvm_vcpu *vcpu); -#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE - int (*gmem_prepare)(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order); +#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT + int (*gmem_make_private)(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order); #endif #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_RECLAIM void (*gmem_make_shared)(kvm_pfn_t pfn, kvm_pfn_t nr_pages); diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index e0e7ad015839..538ed1e80332 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -160,7 +160,7 @@ config KVM_AMD_SEV depends on CRYPTO_DEV_SP_PSP && !(KVM_AMD=y && CRYPTO_DEV_CCP_DD=m) select ARCH_HAS_CC_PLATFORM select KVM_GENERIC_MEMORY_ATTRIBUTES - select HAVE_KVM_ARCH_GMEM_PREPARE + select HAVE_KVM_ARCH_GMEM_CONVERT select HAVE_KVM_ARCH_GMEM_RECLAIM select HAVE_KVM_ARCH_GMEM_INVALIDATE select HAVE_KVM_ARCH_GMEM_POPULATE diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 4c46081889a6..779889f5e994 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -5112,7 +5112,7 @@ static bool is_large_rmp_possible(struct kvm *kvm, kvm_pfn_t pfn, int order) return false; } -int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order) +int sev_gmem_make_private(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order) { struct kvm_sev_info *sev = to_kvm_sev_info(kvm); kvm_pfn_t pfn_aligned; diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 44c3af6f71d8..d9f632ea8057 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -5450,7 +5450,7 @@ struct kvm_x86_ops svm_x86_ops __initdata = { .vm_copy_enc_context_from = sev_vm_copy_enc_context_from, .vm_move_enc_context_from = sev_vm_move_enc_context_from, - .gmem_prepare = sev_gmem_prepare, + .gmem_make_private = sev_gmem_make_private, .gmem_make_shared = sev_gmem_make_shared, .gmem_invalidate_range = sev_gmem_invalidate_range, .gmem_max_mapping_level = sev_gmem_max_mapping_level, diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 51e3494e7802..b5cd8437988f 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -1009,7 +1009,7 @@ int sev_cpu_init(struct svm_cpu_data *sd); int sev_dev_get_attr(u32 group, u64 attr, u64 *val); extern unsigned int max_sev_asid; void sev_handle_rmp_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code); -int sev_gmem_prepare(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order); +int sev_gmem_make_private(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order); void sev_gmem_make_shared(kvm_pfn_t pfn, kvm_pfn_t nr_pages); void sev_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range); int sev_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0075815acdd5..512bcc35507a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10589,10 +10589,10 @@ bool kvm_arch_supports_gmem_init_shared(struct kvm *kvm) return !kvm_arch_has_private_mem(kvm); } -#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) +#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT +int kvm_arch_gmem_make_private(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, int max_order) { - return kvm_x86_call(gmem_prepare)(kvm, pfn, gfn, max_order); + return kvm_x86_call(gmem_make_private)(kvm, pfn, gfn, max_order); } #endif diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 46c8d18fd043..ecdda1f00c6c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2572,8 +2572,9 @@ static inline int kvm_gmem_get_pfn(struct kvm *kvm, } #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); +#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT +int kvm_arch_gmem_make_private(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, + int max_order); #endif #ifdef CONFIG_HAVE_KVM_ARCH_GMEM_POPULATE diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index 617876993225..c3c0ee253fc7 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -107,7 +107,7 @@ config KVM_GUEST_MEMFD select XARRAY_MULTI bool -config HAVE_KVM_ARCH_GMEM_PREPARE +config HAVE_KVM_ARCH_GMEM_CONVERT bool depends on KVM_GUEST_MEMFD diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 25da7778af01..6635ed05f411 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -73,11 +73,11 @@ static bool kvm_gmem_is_shared_mem(struct inode *inode, pgoff_t index) static int __kvm_gmem_prepare_folio(struct kvm *kvm, struct kvm_memory_slot *slot, pgoff_t index, struct folio *folio) { -#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_PREPARE +#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_CONVERT kvm_pfn_t pfn = folio_file_pfn(folio, index); gfn_t gfn = slot->base_gfn + index - slot->gmem.pgoff; - return kvm_arch_gmem_prepare(kvm, gfn, pfn, folio_order(folio)); + return kvm_arch_gmem_make_private(kvm, gfn, pfn, folio_order(folio)); #else return 0; #endif