KVM: Reduce stack usage in kvm_vcpu_ioctl()

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Dave Hansen 2008-08-11 10:01:46 -07:00 committed by Avi Kivity
parent f0d662759a
commit fa3795a730

View File

@ -1126,6 +1126,8 @@ static long kvm_vcpu_ioctl(struct file *filp,
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
int r;
struct kvm_fpu *fpu = NULL;
struct kvm_sregs *kvm_sregs = NULL;
if (vcpu->kvm->mm != current->mm)
return -EIO;
@ -1173,25 +1175,28 @@ out_free2:
break;
}
case KVM_GET_SREGS: {
struct kvm_sregs kvm_sregs;
memset(&kvm_sregs, 0, sizeof kvm_sregs);
r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
r = -ENOMEM;
if (!kvm_sregs)
goto out;
r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
if (r)
goto out;
r = -EFAULT;
if (copy_to_user(argp, &kvm_sregs, sizeof kvm_sregs))
if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
goto out;
r = 0;
break;
}
case KVM_SET_SREGS: {
struct kvm_sregs kvm_sregs;
r = -EFAULT;
if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
r = -ENOMEM;
if (!kvm_sregs)
goto out;
r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
r = -EFAULT;
if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
goto out;
r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
if (r)
goto out;
r = 0;
@ -1272,25 +1277,28 @@ out_free2:
break;
}
case KVM_GET_FPU: {
struct kvm_fpu fpu;
memset(&fpu, 0, sizeof fpu);
r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, &fpu);
fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
r = -ENOMEM;
if (!fpu)
goto out;
r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
if (r)
goto out;
r = -EFAULT;
if (copy_to_user(argp, &fpu, sizeof fpu))
if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
goto out;
r = 0;
break;
}
case KVM_SET_FPU: {
struct kvm_fpu fpu;
r = -EFAULT;
if (copy_from_user(&fpu, argp, sizeof fpu))
fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
r = -ENOMEM;
if (!fpu)
goto out;
r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, &fpu);
r = -EFAULT;
if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
goto out;
r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
if (r)
goto out;
r = 0;
@ -1300,6 +1308,8 @@ out_free2:
r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
}
out:
kfree(fpu);
kfree(kvm_sregs);
return r;
}