xref: /linux/kernel/entry/kvm.c (revision 79e03f29fc84db76f78834b1f73ed329b377d753)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/entry-kvm.h>
4 #include <linux/kvm_host.h>
5 
6 static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work)
7 {
8 	do {
9 		int ret;
10 
11 		if (ti_work & _TIF_NOTIFY_SIGNAL)
12 			tracehook_notify_signal();
13 
14 		if (ti_work & _TIF_SIGPENDING) {
15 			kvm_handle_signal_exit(vcpu);
16 			return -EINTR;
17 		}
18 
19 		if (ti_work & _TIF_NEED_RESCHED)
20 			schedule();
21 
22 		if (ti_work & _TIF_NOTIFY_RESUME)
23 			tracehook_notify_resume(NULL);
24 
25 		ret = arch_xfer_to_guest_mode_handle_work(vcpu, ti_work);
26 		if (ret)
27 			return ret;
28 
29 		ti_work = read_thread_flags();
30 	} while (ti_work & XFER_TO_GUEST_MODE_WORK || need_resched());
31 	return 0;
32 }
33 
34 int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu)
35 {
36 	unsigned long ti_work;
37 
38 	/*
39 	 * This is invoked from the outer guest loop with interrupts and
40 	 * preemption enabled.
41 	 *
42 	 * KVM invokes xfer_to_guest_mode_work_pending() with interrupts
43 	 * disabled in the inner loop before going into guest mode. No need
44 	 * to disable interrupts here.
45 	 */
46 	ti_work = read_thread_flags();
47 	if (!(ti_work & XFER_TO_GUEST_MODE_WORK))
48 		return 0;
49 
50 	return xfer_to_guest_mode_work(vcpu, ti_work);
51 }
52 EXPORT_SYMBOL_GPL(xfer_to_guest_mode_handle_work);
53