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 19 struct 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 */ 30 static 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 34 static 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 */ 48 int 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 */ 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 */ 72 static 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 */ 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_KVM_XFER_TO_GUEST_WORK */ 94 95 #endif 96