[PATCH v12 05/84] KVM: Add kvm_release_page_unused() API to put pages that KVM never consumes

Sean Christopherson
2024-07-26T23:55:18Z

Add an API to release an unused page, i.e. to put a page without marking
it accessed or dirty. The API will be used when KVM faults-in a page but
bails before installing the guest mapping (and other similar flows).

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
include/linux/kvm_host.h | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 3d9617d1de41..c5d39a337aa3 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1201,6 +1201,15 @@ unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable);
unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn);
unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, gfn_t gfn,
bool *writable);
+
+static inline void kvm_release_page_unused(struct page *page)
+{
+ if (!page)
+ return;
+
+ put_page(page);
+}
+
void kvm_release_page_clean(struct page *page);
void kvm_release_page_dirty(struct page *page);