1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_ENTRYKVM_H
3 #define __LINUX_ENTRYKVM_H
4
5 #include <linux/static_call_types.h>
6 #include <linux/resume_user_mode.h>
7 #include <linux/syscalls.h>
8 #include <linux/seccomp.h>
9 #include <linux/sched.h>
10 #include <linux/tick.h>
11
12 /* Transfer to guest mode work */
13 #ifdef CONFIG_KVM_XFER_TO_GUEST_WORK
14
15 #ifndef ARCH_XFER_TO_GUEST_MODE_WORK
16 # define ARCH_XFER_TO_GUEST_MODE_WORK (0)
17 #endif
18
19 #define XFER_TO_GUEST_MODE_WORK \
20 (_TIF_NEED_RESCHED | _TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL | \
21 _TIF_NOTIFY_RESUME | ARCH_XFER_TO_GUEST_MODE_WORK)
22
23 struct kvm_vcpu;
24
25 /**
26 * arch_xfer_to_guest_mode_handle_work - Architecture specific xfer to guest
27 * mode work handling function.
28 * @vcpu: Pointer to current's VCPU data
29 * @ti_work: Cached TIF flags gathered in xfer_to_guest_mode_handle_work()
30 *
31 * Invoked from xfer_to_guest_mode_handle_work(). Defaults to NOOP. Can be
32 * replaced by architecture specific code.
33 */
34 static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu,
35 unsigned long ti_work);
36
37 #ifndef arch_xfer_to_guest_mode_work
38 static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu,
39 unsigned long ti_work)
40 {
41 return 0;
42 }
43 #endif
44
45 /**
46 * xfer_to_guest_mode_handle_work - Check and handle pending work which needs
47 * to be handled before going to guest mode
48 * @vcpu: Pointer to current's VCPU data
49 *
50 * Returns: 0 or an error code
51 */
52 int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu);
53
54 /**
55 * xfer_to_guest_mode_prepare - Perform last minute preparation work that
56 * need to be handled while IRQs are disabled
57 * upon entering to guest.
58 *
59 * Has to be invoked with interrupts disabled before the last call
60 * to xfer_to_guest_mode_work_pending().
61 */
62 static inline void xfer_to_guest_mode_prepare(void)
63 {
64 lockdep_assert_irqs_disabled();
65 tick_nohz_user_enter_prepare();
66 }
67
68 /**
69 * __xfer_to_guest_mode_work_pending - Check if work is pending
70 *
71 * Returns: True if work pending, False otherwise.
72 *
73 * Bare variant of xfer_to_guest_mode_work_pending(). Can be called from
74 * interrupt enabled code for racy quick checks with care.
75 */
76 static inline bool __xfer_to_guest_mode_work_pending(void)
77 {
78 unsigned long ti_work = read_thread_flags();
79
80 return !!(ti_work & XFER_TO_GUEST_MODE_WORK);
81 }
82
83 /**
84 * xfer_to_guest_mode_work_pending - Check if work is pending which needs to be
85 * handled before returning to guest mode
86 *
87 * Returns: True if work pending, False otherwise.
88 *
89 * Has to be invoked with interrupts disabled before the transition to
90 * guest mode.
91 */
92 static inline bool xfer_to_guest_mode_work_pending(void)
93 {
94 lockdep_assert_irqs_disabled();
95 return __xfer_to_guest_mode_work_pending();
96 }
97 #endif /* CONFIG_KVM_XFER_TO_GUEST_WORK */
98
99 #endif
100
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