lkml.org 
[lkml]   [2021]   [Jun]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 4/9] KVM: X86: Introduce pte_list_count() helper
Date
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@redhat.com>
---
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 eb16c1dbbb32..b3f738a7c05e 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -990,6 +990,27 @@ 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,
struct kvm_memory_slot *slot)
{
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 35567293c1fd..325b4242deed 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
\
 
 \ /
  Last update: 2021-06-25 17:32    [W:2.837 / U:0.444 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site