Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_ENTRYKVM_H
3#define __LINUX_ENTRYKVM_H
4
5#include <linux/entry-common.h>
6#include <linux/tick.h>
7
8/* Transfer to guest mode work */
9#ifdef CONFIG_KVM_XFER_TO_GUEST_WORK
10
11#ifndef ARCH_XFER_TO_GUEST_MODE_WORK
12# define ARCH_XFER_TO_GUEST_MODE_WORK (0)
13#endif
14
15#define XFER_TO_GUEST_MODE_WORK \
16 (_TIF_NEED_RESCHED | _TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL | \
17 _TIF_NOTIFY_RESUME | ARCH_XFER_TO_GUEST_MODE_WORK)
18
19struct kvm_vcpu;
20
21/**
22 * arch_xfer_to_guest_mode_handle_work - Architecture specific xfer to guest
23 * mode work handling function.
24 * @vcpu: Pointer to current's VCPU data
25 * @ti_work: Cached TIF flags gathered in xfer_to_guest_mode_handle_work()
26 *
27 * Invoked from xfer_to_guest_mode_handle_work(). Defaults to NOOP. Can be
28 * replaced by architecture specific code.
29 */
30static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu,
31 unsigned long ti_work);
32
33#ifndef arch_xfer_to_guest_mode_work
34static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu,
35 unsigned long ti_work)
36{
37 return 0;
38}
39#endif
40
41/**
42 * xfer_to_guest_mode_handle_work - Check and handle pending work which needs
43 * to be handled before going to guest mode
44 * @vcpu: Pointer to current's VCPU data
45 *
46 * Returns: 0 or an error code
47 */
48int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu);
49
50/**
51 * xfer_to_guest_mode_prepare - Perform last minute preparation work that
52 * need to be handled while IRQs are disabled
53 * upon entering to guest.
54 *
55 * Has to be invoked with interrupts disabled before the last call
56 * to xfer_to_guest_mode_work_pending().
57 */
58static inline void xfer_to_guest_mode_prepare(void)
59{
60 lockdep_assert_irqs_disabled();
61 tick_nohz_user_enter_prepare();
62}
63
64/**
65 * __xfer_to_guest_mode_work_pending - Check if work is pending
66 *
67 * Returns: True if work pending, False otherwise.
68 *
69 * Bare variant of xfer_to_guest_mode_work_pending(). Can be called from
70 * interrupt enabled code for racy quick checks with care.
71 */
72static inline bool __xfer_to_guest_mode_work_pending(void)
73{
74 unsigned long ti_work = READ_ONCE(current_thread_info()->flags);
75
76 return !!(ti_work & XFER_TO_GUEST_MODE_WORK);
77}
78
79/**
80 * xfer_to_guest_mode_work_pending - Check if work is pending which needs to be
81 * handled before returning to guest mode
82 *
83 * Returns: True if work pending, False otherwise.
84 *
85 * Has to be invoked with interrupts disabled before the transition to
86 * guest mode.
87 */
88static inline bool xfer_to_guest_mode_work_pending(void)
89{
90 lockdep_assert_irqs_disabled();
91 return __xfer_to_guest_mode_work_pending();
92}
93#endif /* CONFIG_KVM_XFER_TO_GUEST_WORK */
94
95#endif