From: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxx>
The functionality of write protection for all guest memory is ready,
it is the time to make its usable for userspace which is indicated
by KVM_CAP_X86_WRITE_PROTECT_ALL_MEM
Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxx>
---
arch/x86/kvm/x86.c | 21 +++++++++++++++++++++
include/uapi/linux/kvm.h | 2 ++
2 files changed, 23 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a2cd099..ad62c44 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2723,6 +2723,17 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_X2APIC_API:
r = KVM_X2APIC_API_VALID_FLAGS;
break;
+ case KVM_CAP_X86_WRITE_PROTECT_ALL_MEM:
+ /*
+ * do not enable it if PML is supported, this is also the
+ * hint to tell userspace write-protect is not needed for
+ * dirty log.
+ */
+ if (kvm_x86_ops->slot_enable_log_dirty)
+ r = 0;
+ else
+ r = 1;
+ break;
default:
r = 0;
break;
@@ -4208,6 +4219,16 @@ long kvm_arch_vm_ioctl(struct file *filp,
r = 0;
break;
}
+ case KVM_WRITE_PROTECT_ALL_MEM: {
+ if (kvm_x86_ops->slot_enable_log_dirty) {
+ r = -EINVAL;
+ break;
+ }
+
+ kvm_mmu_write_protect_all_pages(kvm, !!arg);
+ r = 0;
+ break;
+ }
case KVM_ENABLE_CAP: {
struct kvm_enable_cap cap;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 577429a..7d4a395 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -895,6 +895,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_SPAPR_TCE_VFIO 142
#define KVM_CAP_X86_GUEST_MWAIT 143
#define KVM_CAP_ARM_USER_IRQ 144
+#define KVM_CAP_X86_WRITE_PROTECT_ALL_MEM 145
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1144,6 +1145,7 @@ struct kvm_vfio_spapr_tce {
struct kvm_userspace_memory_region)
#define KVM_SET_TSS_ADDR _IO(KVMIO, 0x47)
#define KVM_SET_IDENTITY_MAP_ADDR _IOW(KVMIO, 0x48, __u64)
+#define KVM_WRITE_PROTECT_ALL_MEM _IO(KVMIO, 0x49)
/* enable ucontrol for s390 */
struct kvm_s390_ucas_mapping {
--
2.9.4
