KVM: Recalculate mmu pages needed for every memory region change
Instead of incrementally changing the mmu cache size for every memory slot
operation, recalculate it from scratch. This is simpler and safer.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 729573b..93ecafb 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -333,26 +333,13 @@
if (mem->slot >= kvm->nmemslots)
kvm->nmemslots = mem->slot + 1;
- if (!kvm->n_requested_mmu_pages) {
- unsigned int n_pages;
-
- if (npages) {
- n_pages = npages * KVM_PERMILLE_MMU_PAGES / 1000;
- kvm_mmu_change_mmu_pages(kvm, kvm->n_alloc_mmu_pages +
- n_pages);
- } else {
- unsigned int nr_mmu_pages;
-
- n_pages = old.npages * KVM_PERMILLE_MMU_PAGES / 1000;
- nr_mmu_pages = kvm->n_alloc_mmu_pages - n_pages;
- nr_mmu_pages = max(nr_mmu_pages,
- (unsigned int) KVM_MIN_ALLOC_MMU_PAGES);
- kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);
- }
- }
-
*memslot = new;
+ if (!kvm->n_requested_mmu_pages) {
+ unsigned int nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm);
+ kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);
+ }
+
kvm_mmu_slot_remove_write_access(kvm, mem->slot);
kvm_flush_remote_tlbs(kvm);