[PATCH v5 1/7] KVM: guest_memfd: Plumb the number of pages and max order into .invalidate()

From: Sean Christopherson

Date: Tue Jul 14 2026 - 19:13:04 EST


Plumb the number of pages to "invalidate", i.e. reclaim, along with the max
order with which the pages can be mapped. This will allow x86 to combine
its vendor-specific implementations for conversion and reclaim, a.k.a.
preparation and invalidation, into a single hook.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 4 ++--
include/linux/kvm_host.h | 2 +-
virt/kvm/guest_memfd.c | 7 ++-----
3 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1f5dc685f049..a2cbf6fae118 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10627,9 +10627,9 @@ int kvm_arch_gmem_prepare(struct kvm *kvm, gfn_t gfn, kvm_pfn_t pfn, int max_ord
#endif

#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
-void kvm_arch_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end)
+void kvm_arch_gmem_invalidate(kvm_pfn_t pfn, kvm_pfn_t nr_pages, int max_order)
{
- kvm_x86_call(gmem_invalidate)(start, end);
+ kvm_x86_call(gmem_invalidate)(pfn, pfn + nr_pages);
}
void kvm_arch_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range)
{
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 9db6eb4023c4..996b39ebdb68 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2614,7 +2614,7 @@ long kvm_gmem_populate(struct kvm *kvm, gfn_t start_gfn, void __user *src,
#endif

#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
-void kvm_arch_gmem_invalidate(kvm_pfn_t start, kvm_pfn_t end);
+void kvm_arch_gmem_invalidate(kvm_pfn_t pfn, kvm_pfn_t nr_pages, int order);
void kvm_arch_gmem_invalidate_range(struct kvm *kvm, struct kvm_gfn_range *range);
#endif

diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index 171a9da1b685..99c070bfd446 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -530,11 +530,8 @@ static int kvm_gmem_error_folio(struct address_space *mapping, struct folio *fol
#ifdef CONFIG_HAVE_KVM_ARCH_GMEM_INVALIDATE
static void kvm_gmem_free_folio(struct folio *folio)
{
- struct page *page = folio_page(folio, 0);
- kvm_pfn_t pfn = page_to_pfn(page);
- int order = folio_order(folio);
-
- kvm_arch_gmem_invalidate(pfn, pfn + (1ul << order));
+ kvm_arch_gmem_invalidate(folio_file_pfn(folio, 0), folio_nr_pages(folio),
+ folio_order(folio));
}
#endif

--
2.55.0.141.g00534a21ce-goog