KVM: Convert KVM_ARCH_WANT_MMU_NOTIFIER to CONFIG_KVM_GENERIC_MMU_NOTIFIER

Convert KVM_ARCH_WANT_MMU_NOTIFIER into a Kconfig and select it where
appropriate to effectively maintain existing behavior.  Using a proper
Kconfig will simplify building more functionality on top of KVM's
mmu_notifier infrastructure.

Add a forward declaration of kvm_gfn_range to kvm_types.h so that
including arch/powerpc/include/asm/kvm_ppc.h's with CONFIG_KVM=n doesn't
generate warnings due to kvm_gfn_range being undeclared.  PPC defines
hooks for PR vs. HV without guarding them via #ifdeffery, e.g.

  bool (*unmap_gfn_range)(struct kvm *kvm, struct kvm_gfn_range *range);
  bool (*age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);
  bool (*test_age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);
  bool (*set_spte_gfn)(struct kvm *kvm, struct kvm_gfn_range *range);

Alternatively, PPC could forward declare kvm_gfn_range, but there's no
good reason not to define it in common KVM.

Acked-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Message-Id: <20231027182217.3615211-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 5653d3553e3ee57db790a5bb4c79211c2e84fe75..9029fe09f3f69d54dc9bef540a5a8a965d9c9e24 100644 (file)
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -954,8 +954,6 @@ int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
 int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
                              struct kvm_vcpu_events *events);
 
-#define KVM_ARCH_WANT_MMU_NOTIFIER
-
 void kvm_arm_halt_guest(struct kvm *kvm);
 void kvm_arm_resume_guest(struct kvm *kvm);
 

diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 83c1e09be42e5b609d44d653e184b44d9cdc347c..1a777715199fa82bc1edd96da155058f4a4c72df 100644 (file)
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -22,7 +22,7 @@ menuconfig KVM
        bool "Kernel-based Virtual Machine (KVM) support"
        depends on HAVE_KVM
        select KVM_GENERIC_HARDWARE_ENABLING
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        select PREEMPT_NOTIFIERS
        select HAVE_KVM_CPU_RELAX_INTERCEPT
        select KVM_MMIO

diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
index 11328700d4fa8d37aca8371c43b0d38e5f5fd2a0..b108301c2e5aaffed9427862e94460edfb771ccd 100644 (file)
--- a/arch/loongarch/include/asm/kvm_host.h
+++ b/arch/loongarch/include/asm/kvm_host.h
@@ -183,7 +183,6 @@ void kvm_flush_tlb_all(void);
 void kvm_flush_tlb_gpa(struct kvm_vcpu *vcpu, unsigned long gpa);
 int kvm_handle_mm_fault(struct kvm_vcpu *vcpu, unsigned long badv, bool write);
 
-#define KVM_ARCH_WANT_MMU_NOTIFIER
 void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
 int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end, bool blockable);
 int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);

diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig
index fda425babfb203d3fc36052b9722515ab7c568e6..f22bae89b07d3f54be662935598a2d664504e361 100644 (file)
--- a/arch/loongarch/kvm/Kconfig
+++ b/arch/loongarch/kvm/Kconfig
@@ -26,9 +26,9 @@ config KVM
        select HAVE_KVM_VCPU_ASYNC_IOCTL
        select KVM_GENERIC_DIRTYLOG_READ_PROTECT
        select KVM_GENERIC_HARDWARE_ENABLING
+       select KVM_GENERIC_MMU_NOTIFIER
        select KVM_MMIO
        select KVM_XFER_TO_GUEST_WORK
-       select MMU_NOTIFIER
        select PREEMPT_NOTIFIERS
        help
          Support hosting virtualized guest machines using

diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 54a85f1d4f2c8d8822f25974c000d2d7aafc86c0..179f320cc2313b985d3a6d03c6437c85aa69a7dc 100644 (file)
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -810,8 +810,6 @@ int kvm_mips_mkclean_gpa_pt(struct kvm *kvm, gfn_t start_gfn, gfn_t end_gfn);
 pgd_t *kvm_pgd_alloc(void);
 void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu);
 
-#define KVM_ARCH_WANT_MMU_NOTIFIER
-
 /* Emulation */
 enum emulation_result update_pc(struct kvm_vcpu *vcpu, u32 cause);
 int kvm_get_badinstr(u32 *opc, struct kvm_vcpu *vcpu, u32 *out);

diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
index a8cdba75f98dde949c9cd86ef073027cc49bfad3..c04987d2ed2e3e3c9b56015eaa0be8bd08ed62f2 100644 (file)
--- a/arch/mips/kvm/Kconfig
+++ b/arch/mips/kvm/Kconfig
@@ -25,7 +25,7 @@ config KVM
        select HAVE_KVM_EVENTFD
        select HAVE_KVM_VCPU_ASYNC_IOCTL
        select KVM_MMIO
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        select INTERVAL_TREE
        select KVM_GENERIC_HARDWARE_ENABLING
        help

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 14ee0dece8538be1c4c743ebf59c8d808a178b22..4b5c3f2acf78f555c5705bb8dd49766df3c41889 100644 (file)
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -62,8 +62,6 @@
 
 #include <linux/mmu_notifier.h>
 
-#define KVM_ARCH_WANT_MMU_NOTIFIER
-
 #define HPTEG_CACHE_NUM                        (1 << 15)
 #define HPTEG_HASH_BITS_PTE            13
 #define HPTEG_HASH_BITS_PTE_LONG       12

diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index 902611954200df90c43e2b2516ce242006dba09c..b33358ee642440adba4836e3257107af4bf11b06 100644 (file)
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -42,7 +42,7 @@ config KVM_BOOK3S_64_HANDLER
 config KVM_BOOK3S_PR_POSSIBLE
        bool
        select KVM_MMIO
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
 
 config KVM_BOOK3S_HV_POSSIBLE
        bool
@@ -85,7 +85,7 @@ config KVM_BOOK3S_64_HV
        tristate "KVM for POWER7 and later using hypervisor mode in host"
        depends on KVM_BOOK3S_64 && PPC_POWERNV
        select KVM_BOOK3S_HV_POSSIBLE
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        select CMA
        help
          Support running unmodified book3s_64 guest kernels in
@@ -194,7 +194,7 @@ config KVM_E500V2
        depends on !CONTEXT_TRACKING_USER
        select KVM
        select KVM_MMIO
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        help
          Support running unmodified E500 guest kernels in virtual machines on
          E500v2 host processors.
@@ -211,7 +211,7 @@ config KVM_E500MC
        select KVM
        select KVM_MMIO
        select KVM_BOOKE_HV
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        help
          Support running unmodified E500MC/E5500/E6500 guest kernels in
          virtual machines on E500MC/E5500/E6500 host processors.

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 8d3ec483bc2b203ca162401c8a5afea0d919ca0e..aac75c98a9565bea1834e225da911c1aed07a95a 100644 (file)
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -632,9 +632,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
                break;
 #endif
        case KVM_CAP_SYNC_MMU:
-#if !defined(CONFIG_MMU_NOTIFIER) || !defined(KVM_ARCH_WANT_MMU_NOTIFIER)
-               BUILD_BUG();
-#endif
+               BUILD_BUG_ON(!IS_ENABLED(CONFIG_KVM_GENERIC_MMU_NOTIFIER));
                r = 1;
                break;
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE

diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index 0eefd9c991ae24e99ea946ac11615075aefbf085..6964dd235e97f090a8dd6159d338050d47834a08 100644 (file)
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -267,8 +267,6 @@ struct kvm_vcpu_arch {
 static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
 
-#define KVM_ARCH_WANT_MMU_NOTIFIER
-
 #define KVM_RISCV_GSTAGE_TLB_MIN_ORDER         12
 
 void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid,

diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig
index dfc237d7875b53bb2f3e7e716c1b85af8b335458..ae2e05f050ece1eff54c496f8bdf13d168bd5cfa 100644 (file)
--- a/arch/riscv/kvm/Kconfig
+++ b/arch/riscv/kvm/Kconfig
@@ -30,7 +30,7 @@ config KVM
        select KVM_GENERIC_HARDWARE_ENABLING
        select KVM_MMIO
        select KVM_XFER_TO_GUEST_WORK
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        select PREEMPT_NOTIFIERS
        help
          Support hosting virtualized guest machines.

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d7036982332e33d7b858379785b9071ad4992451..6f559fb75e6dd1bb9800beeb68f439344b7274f4 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2141,8 +2141,6 @@ enum {
 # define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, 0)
 #endif
 
-#define KVM_ARCH_WANT_MMU_NOTIFIER
-
 int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v);
 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
 int kvm_cpu_has_extint(struct kvm_vcpu *v);

diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 950c12868d304004ff56e7bc95f7c5f395766a33..e61383674c75632a6316bd5a697d54d490360a5a 100644 (file)
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -24,7 +24,7 @@ config KVM
        depends on HIGH_RES_TIMERS
        depends on X86_LOCAL_APIC
        select PREEMPT_NOTIFIERS
-       select MMU_NOTIFIER
+       select KVM_GENERIC_MMU_NOTIFIER
        select HAVE_KVM_IRQCHIP
        select HAVE_KVM_PFNCACHE
        select HAVE_KVM_IRQFD

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 11d0916883460b70c598adcf98f4867efae816fd..5faba69403ac49f1d258f75bb289753ca3e82a6a 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -253,7 +253,7 @@ bool kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu);
 #endif
 
-#ifdef KVM_ARCH_WANT_MMU_NOTIFIER
+#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
 union kvm_mmu_notifier_arg {
        pte_t pte;
 };
@@ -783,7 +783,7 @@ struct kvm {
        struct hlist_head irq_ack_notifier_list;
 #endif
 
-#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
+#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
        struct mmu_notifier mmu_notifier;
        unsigned long mmu_invalidate_seq;
        long mmu_invalidate_in_progress;
@@ -1946,7 +1946,7 @@ extern const struct _kvm_stats_desc kvm_vm_stats_desc[];
 extern const struct kvm_stats_header kvm_vcpu_stats_header;
 extern const struct _kvm_stats_desc kvm_vcpu_stats_desc[];
 
-#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
+#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
 static inline int mmu_invalidate_retry(struct kvm *kvm, unsigned long mmu_seq)
 {
        if (unlikely(kvm->mmu_invalidate_in_progress))

diff --git a/include/linux/kvm_types.h b/include/linux/kvm_types.h
index 6f4737d5046a41181401c1be7a663f0d7eb76a95..9d1f7835d8c13917ad171297752e072c04bec1b3 100644 (file)
--- a/include/linux/kvm_types.h
+++ b/include/linux/kvm_types.h
@@ -6,6 +6,7 @@
 struct kvm;
 struct kvm_async_pf;
 struct kvm_device_ops;
+struct kvm_gfn_range;
 struct kvm_interrupt;
 struct kvm_irq_routing_table;
 struct kvm_memory_slot;

diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index 484d0873061ca5041c546f1c44520a1848ec1d16..ecae2914c97e48e27ab8f0aa89a929960da769bf 100644 (file)
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -92,3 +92,7 @@ config HAVE_KVM_PM_NOTIFIER
 
 config KVM_GENERIC_HARDWARE_ENABLING
        bool
+
+config KVM_GENERIC_MMU_NOTIFIER
+       select MMU_NOTIFIER
+       bool

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 5422ce20dcbace265f2b512305b4feebda914743..dc81279ea385017e0e1c77424e432929f701949a 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -535,7 +535,7 @@ void kvm_destroy_vcpus(struct kvm *kvm)
 }
 EXPORT_SYMBOL_GPL(kvm_destroy_vcpus);
 
-#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
+#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
 {
        return container_of(mn, struct kvm, mmu_notifier);
@@ -962,14 +962,14 @@ static int kvm_init_mmu_notifier(struct kvm *kvm)
        return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
 }
 
-#else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
+#else  /* !CONFIG_KVM_GENERIC_MMU_NOTIFIER */
 
 static int kvm_init_mmu_notifier(struct kvm *kvm)
 {
        return 0;
 }
 
-#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
+#endif /* CONFIG_KVM_GENERIC_MMU_NOTIFIER */
 
 #ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
 static int kvm_pm_notifier_call(struct notifier_block *bl,
@@ -1289,7 +1289,7 @@ out_err:
 out_err_no_debugfs:
        kvm_coalesced_mmio_free(kvm);
 out_no_coalesced_mmio:
-#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
+#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
        if (kvm->mmu_notifier.ops)
                mmu_notifier_unregister(&kvm->mmu_notifier, current->mm);
 #endif
@@ -1349,7 +1349,7 @@ static void kvm_destroy_vm(struct kvm *kvm)
                kvm->buses[i] = NULL;
        }
        kvm_coalesced_mmio_free(kvm);
-#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
+#ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
        mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
        /*
         * At this point, pending calls to invalidate_range_start()