xref: /linux/include/linux/entry-virt.h (revision 221533629550e920580ab428f13ffebf54063b95)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_ENTRYVIRT_H
3 #define __LINUX_ENTRYVIRT_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_VIRT_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_NEED_RESCHED_LAZY | _TIF_SIGPENDING | \
21 	 _TIF_NOTIFY_SIGNAL | _TIF_NOTIFY_RESUME |			\
22 	 ARCH_XFER_TO_GUEST_MODE_WORK)
23 
24 /**
25  * arch_xfer_to_guest_mode_handle_work - Architecture specific xfer to guest
26  *					 mode work handling function.
27  * @vcpu:	Pointer to current's VCPU data
28  * @ti_work:	Cached TIF flags gathered in xfer_to_guest_mode_handle_work()
29  *
30  * Invoked from xfer_to_guest_mode_handle_work(). Defaults to NOOP. Can be
31  * replaced by architecture specific code.
32  */
33 static inline int arch_xfer_to_guest_mode_handle_work(unsigned long ti_work);
34 
35 #ifndef arch_xfer_to_guest_mode_work
arch_xfer_to_guest_mode_handle_work(unsigned long ti_work)36 static inline int arch_xfer_to_guest_mode_handle_work(unsigned long ti_work)
37 {
38 	return 0;
39 }
40 #endif
41 
42 /**
43  * xfer_to_guest_mode_handle_work - Check and handle pending work which needs
44  *				    to be handled before going to guest mode
45  *
46  * Returns: 0 or an error code
47  */
48 int xfer_to_guest_mode_handle_work(void);
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  */
xfer_to_guest_mode_prepare(void)58 static 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  */
__xfer_to_guest_mode_work_pending(void)72 static inline bool __xfer_to_guest_mode_work_pending(void)
73 {
74 	unsigned long ti_work = read_thread_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  */
xfer_to_guest_mode_work_pending(void)88 static 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_VIRT_XFER_TO_GUEST_WORK */
94 
95 #endif
96