1 /****************************************************************************** 2 * evtchn.h 3 * 4 * Data structures and definitions private to the FreeBSD implementation 5 * of the Xen event channel API. 6 * 7 * Copyright (c) 2004, K A Fraser 8 * Copyright (c) 2012, Spectra Logic Corporation 9 * Copyright © 2022, Elliott Mitchell 10 * 11 * This file may be distributed separately from the Linux kernel, or 12 * incorporated into other software packages, subject to the following license: 13 * 14 * Permission is hereby granted, free of charge, to any person obtaining a copy 15 * of this source file (the "Software"), to deal in the Software without 16 * restriction, including without limitation the rights to use, copy, modify, 17 * merge, publish, distribute, sublicense, and/or sell copies of the Software, 18 * and to permit persons to whom the Software is furnished to do so, subject to 19 * the following conditions: 20 * 21 * The above copyright notice and this permission notice shall be included in 22 * all copies or substantial portions of the Software. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 25 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 26 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 27 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 28 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 29 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 30 * IN THE SOFTWARE. 31 */ 32 33 #ifndef __XEN_EVTCHN_EVTCHNVAR_H__ 34 #define __XEN_EVTCHN_EVTCHNVAR_H__ 35 36 #include <xen/hypervisor.h> 37 #include <contrib/xen/event_channel.h> 38 39 /* Macros for accessing event channel values */ 40 #define EVTCHN_PTR(type, port) \ 41 (HYPERVISOR_shared_info->evtchn_##type + ((port) / __LONG_BIT)) 42 #define EVTCHN_BIT(port) ((port) & (__LONG_BIT - 1)) 43 #define EVTCHN_MASK(port) (1UL << EVTCHN_BIT(port)) 44 45 /** 46 * Disable signal delivery for an event channel port, returning its 47 * previous mask state. 48 * 49 * \param port The event channel port to query and mask. 50 * 51 * \returns 1 if event delivery was previously disabled. Otherwise 0. 52 */ 53 static inline int 54 evtchn_test_and_set_mask(evtchn_port_t port) 55 { 56 57 return (atomic_testandset_xen_ulong(EVTCHN_PTR(mask, port), 58 EVTCHN_BIT(port))); 59 } 60 61 /** 62 * Clear any pending event for the given event channel port. 63 * 64 * \param port The event channel port to clear. 65 */ 66 static inline void 67 evtchn_clear_port(evtchn_port_t port) 68 { 69 70 atomic_clear_xen_ulong(EVTCHN_PTR(pending, port), EVTCHN_MASK(port)); 71 } 72 73 /** 74 * Disable signal delivery for an event channel port. 75 * 76 * \param port The event channel port to mask. 77 */ 78 static inline void 79 evtchn_mask_port(evtchn_port_t port) 80 { 81 82 atomic_set_xen_ulong(EVTCHN_PTR(mask, port), EVTCHN_MASK(port)); 83 } 84 85 /** 86 * Enable signal delivery for an event channel port. 87 * 88 * \param port The event channel port to enable. 89 */ 90 static inline void 91 evtchn_unmask_port(evtchn_port_t port) 92 { 93 evtchn_unmask_t op = { .port = port }; 94 95 HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &op); 96 } 97 98 #endif /* __XEN_EVTCHN_EVTCHNVAR_H__ */ 99