diff options
| author |  Sean Christopherson <seanjc@google.com>
| 2023-07-28 18:35:28 -0700 |
|---|---|---|
| committer |  Paolo Bonzini <pbonzini@redhat.com>
| 2023-08-31 14:08:14 -0400 |
| commit | e998fb1a30131fdc7c734bc7422000b41146b631 (patch) | |
| tree | 65e0861288a3c365a500a5e0d0541a56e41836d2 /arch/x86/include | |
| parent | KVM: x86/mmu: Move KVM-only page-track declarations to internal header (diff) | |
| download | linux-e998fb1a30131fdc7c734bc7422000b41146b631.tar.gz linux-e998fb1a30131fdc7c734bc7422000b41146b631.tar.bz2 linux-e998fb1a30131fdc7c734bc7422000b41146b631.zip | |
KVM: x86/mmu: Use page-track notifiers iff there are external users
Disable the page-track notifier code at compile time if there are no
external users, i.e. if CONFIG_KVM_EXTERNAL_WRITE_TRACKING=n. KVM itself
now hooks emulated writes directly instead of relying on the page-track
mechanism.
Provide a stub for "struct kvm_page_track_notifier_node" so that including
headers directly from the command line, e.g. for testing include guards,
doesn't fail due to a struct having an incomplete type.
Reviewed-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Link: https://lore.kernel.org/r/20230729013535.1070024-23-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/kvm_page_track.h | 22 |
2 files changed, 17 insertions, 7 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 93fdc42458cc..29ad3f0a126f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1265,7 +1265,9 @@ struct kvm_arch { * create an NX huge page (without hanging the guest). */ struct list_head possible_nx_huge_pages; +#ifdef CONFIG_KVM_EXTERNAL_WRITE_TRACKING struct kvm_page_track_notifier_head track_notifier_head; +#endif /* * Protects marking pages unsync during page faults, as TDP MMU page * faults only take mmu_lock for read. For simplicity, the unsync diff --git a/arch/x86/include/asm/kvm_page_track.h b/arch/x86/include/asm/kvm_page_track.h index 76c0070dfe2a..61adb07b5927 100644 --- a/arch/x86/include/asm/kvm_page_track.h +++ b/arch/x86/include/asm/kvm_page_track.h @@ -9,6 +9,14 @@ enum kvm_page_track_mode { KVM_PAGE_TRACK_MAX, }; +void kvm_slot_page_track_add_page(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn, + enum kvm_page_track_mode mode); +void kvm_slot_page_track_remove_page(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn, + enum kvm_page_track_mode mode); + +#ifdef CONFIG_KVM_EXTERNAL_WRITE_TRACKING /* * The notifier represented by @kvm_page_track_notifier_node is linked into * the head which will be notified when guest is triggering the track event. @@ -48,18 +56,18 @@ struct kvm_page_track_notifier_node { struct kvm_page_track_notifier_node *node); }; -void kvm_slot_page_track_add_page(struct kvm *kvm, - struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode); -void kvm_slot_page_track_remove_page(struct kvm *kvm, - struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode); - void kvm_page_track_register_notifier(struct kvm *kvm, struct kvm_page_track_notifier_node *n); void kvm_page_track_unregister_notifier(struct kvm *kvm, struct kvm_page_track_notifier_node *n); +#else +/* + * Allow defining a node in a structure even if page tracking is disabled, e.g. + * to play nice with testing headers via direct inclusion from the command line. + */ +struct kvm_page_track_notifier_node {}; +#endif /* CONFIG_KVM_EXTERNAL_WRITE_TRACKING */ #endif |