KVM: Add ioctl to tss address from userspace,
Currently kvm has a wart in that it requires three extra pages for use
as a tss when emulating real mode on Intel. This patch moves the allocation
internally, only requiring userspace to tell us where in the physical address
space we can place the tss.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index a044856..50fd040 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -2661,6 +2661,16 @@
return fd;
}
+static int kvm_vm_ioctl_set_tss_addr(struct kvm *kvm, unsigned long addr)
+{
+ int ret;
+
+ if (addr > (unsigned int)(-3 * PAGE_SIZE))
+ return -1;
+ ret = kvm_x86_ops->set_tss_addr(kvm, addr);
+ return ret;
+}
+
/*
* Creates some virtual cpus. Good luck creating more than one.
*/
@@ -2957,6 +2967,11 @@
int r = -EINVAL;
switch (ioctl) {
+ case KVM_SET_TSS_ADDR:
+ r = kvm_vm_ioctl_set_tss_addr(kvm, arg);
+ if (r < 0)
+ goto out;
+ break;
case KVM_CREATE_VCPU:
r = kvm_vm_ioctl_create_vcpu(kvm, arg);
if (r < 0)
@@ -3183,6 +3198,7 @@
case KVM_CAP_HLT:
case KVM_CAP_MMU_SHADOW_CACHE_CONTROL:
case KVM_CAP_USER_MEMORY:
+ case KVM_CAP_SET_TSS_ADDR:
r = 1;
break;
default: