This helper is used to count the number of rmap entries in the rmap list
pointed by the kvm_rmap_head.
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 21 +++++++++++++++++++++
arch/x86/kvm/mmu/mmu_internal.h | 1 +
2 files changed, 22 insertions(+)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 5429c20cf2cf..16c99f771c9e 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -998,6 +998,27 @@ static void pte_list_remove(struct kvm_rmap_head *rmap_head, u64 *sptep)
__pte_list_remove(sptep, rmap_head);
}
+unsigned int pte_list_count(struct kvm_rmap_head *rmap_head)
+{
+ struct pte_list_desc *desc;
+ unsigned int i, count = 0;
+
+ if (!rmap_head->val)
+ return 0;
+ else if (!(rmap_head->val & 1))
+ return 1;
+
+ desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
+
+ while (desc) {
+ for (i = 0; (i < PTE_LIST_EXT) && desc->sptes[i]; i++)
+ count++;
+ desc = desc->more;
+ }
+
+ return count;
+}
+
static struct kvm_rmap_head *__gfn_to_rmap(gfn_t gfn, int level,
const struct kvm_memory_slot *slot)
{
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index ca7b7595bbfc..62bb8f758b3f 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -131,6 +131,7 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
int min_level);
void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
u64 start_gfn, u64 pages);
+unsigned int pte_list_count(struct kvm_rmap_head *rmap_head);
/*
* Return values of handle_mmio_page_fault, mmu.page_fault, and fast_page_fault().
--
2.31.1
