1/****************************************************************************** 2 * event_channel.h 3 * 4 * Event channels between domains. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to 8 * deal in the Software without restriction, including without limitation the 9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or 10 * sell copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 22 * DEALINGS IN THE SOFTWARE. 23 * 24 * Copyright (c) 2003-2004, K A Fraser. 25 */ 26 27#ifndef __XEN_PUBLIC_EVENT_CHANNEL_H__ 28#define __XEN_PUBLIC_EVENT_CHANNEL_H__ 29 30#include "xen.h" 31 32/* 33 * `incontents 150 evtchn Event Channels 34 * 35 * Event channels are the basic primitive provided by Xen for event 36 * notifications. An event is the Xen equivalent of a hardware 37 * interrupt. They essentially store one bit of information, the event 38 * of interest is signalled by transitioning this bit from 0 to 1. 39 * 40 * Notifications are received by a guest via an upcall from Xen, 41 * indicating when an event arrives (setting the bit). Further 42 * notifications are masked until the bit is cleared again (therefore, 43 * guests must check the value of the bit after re-enabling event 44 * delivery to ensure no missed notifications). 45 * 46 * Event notifications can be masked by setting a flag; this is 47 * equivalent to disabling interrupts and can be used to ensure 48 * atomicity of certain operations in the guest kernel. 49 * 50 * Event channels are represented by the evtchn_* fields in 51 * struct shared_info and struct vcpu_info. 52 */ 53 54/* 55 * ` enum neg_errnoval 56 * ` HYPERVISOR_event_channel_op(enum event_channel_op cmd, void *args) 57 * ` 58 * @cmd == EVTCHNOP_* (event-channel operation). 59 * @args == struct evtchn_* Operation-specific extra arguments (NULL if none). 60 */ 61 62/* ` enum event_channel_op { // EVTCHNOP_* => struct evtchn_* */ 63#define EVTCHNOP_bind_interdomain 0 64#define EVTCHNOP_bind_virq 1 65#define EVTCHNOP_bind_pirq 2 66#define EVTCHNOP_close 3 67#define EVTCHNOP_send 4 68#define EVTCHNOP_status 5 69#define EVTCHNOP_alloc_unbound 6 70#define EVTCHNOP_bind_ipi 7 71#define EVTCHNOP_bind_vcpu 8 72#define EVTCHNOP_unmask 9 73#define EVTCHNOP_reset 10 74/* ` } */ 75 76#ifndef __XEN_EVTCHN_PORT_DEFINED__ 77typedef uint32_t evtchn_port_t; 78DEFINE_XEN_GUEST_HANDLE(evtchn_port_t); 79#define __XEN_EVTCHN_PORT_DEFINED__ 1 80#endif 81 82/* 83 * EVTCHNOP_alloc_unbound: Allocate a port in domain <dom> and mark as 84 * accepting interdomain bindings from domain <remote_dom>. A fresh port 85 * is allocated in <dom> and returned as <port>. 86 * NOTES: 87 * 1. If the caller is unprivileged then <dom> must be DOMID_SELF. 88 * 2. <rdom> may be DOMID_SELF, allowing loopback connections. 89 */ 90struct evtchn_alloc_unbound { 91 /* IN parameters */ 92 domid_t dom, remote_dom; 93 /* OUT parameters */ 94 evtchn_port_t port; 95}; 96typedef struct evtchn_alloc_unbound evtchn_alloc_unbound_t; 97 98/* 99 * EVTCHNOP_bind_interdomain: Construct an interdomain event channel between 100 * the calling domain and <remote_dom>. <remote_dom,remote_port> must identify 101 * a port that is unbound and marked as accepting bindings from the calling 102 * domain. A fresh port is allocated in the calling domain and returned as 103 * <local_port>. 104 * NOTES: 105 * 1. <remote_dom> may be DOMID_SELF, allowing loopback connections. 106 */ 107struct evtchn_bind_interdomain { 108 /* IN parameters. */ 109 domid_t remote_dom; 110 evtchn_port_t remote_port; 111 /* OUT parameters. */ 112 evtchn_port_t local_port; 113}; 114typedef struct evtchn_bind_interdomain evtchn_bind_interdomain_t; 115 116/* 117 * EVTCHNOP_bind_virq: Bind a local event channel to VIRQ <irq> on specified 118 * vcpu. 119 * NOTES: 120 * 1. Virtual IRQs are classified as per-vcpu or global. See the VIRQ list 121 * in xen.h for the classification of each VIRQ. 122 * 2. Global VIRQs must be allocated on VCPU0 but can subsequently be 123 * re-bound via EVTCHNOP_bind_vcpu. 124 * 3. Per-vcpu VIRQs may be bound to at most one event channel per vcpu. 125 * The allocated event channel is bound to the specified vcpu and the 126 * binding cannot be changed. 127 */ 128struct evtchn_bind_virq { 129 /* IN parameters. */ 130 uint32_t virq; /* enum virq */ 131 uint32_t vcpu; 132 /* OUT parameters. */ 133 evtchn_port_t port; 134}; 135typedef struct evtchn_bind_virq evtchn_bind_virq_t; 136 137/* 138 * EVTCHNOP_bind_pirq: Bind a local event channel to a real IRQ (PIRQ <irq>). 139 * NOTES: 140 * 1. A physical IRQ may be bound to at most one event channel per domain. 141 * 2. Only a sufficiently-privileged domain may bind to a physical IRQ. 142 */ 143struct evtchn_bind_pirq { 144 /* IN parameters. */ 145 uint32_t pirq; 146#define BIND_PIRQ__WILL_SHARE 1 147 uint32_t flags; /* BIND_PIRQ__* */ 148 /* OUT parameters. */ 149 evtchn_port_t port; 150}; 151typedef struct evtchn_bind_pirq evtchn_bind_pirq_t; 152 153/* 154 * EVTCHNOP_bind_ipi: Bind a local event channel to receive events. 155 * NOTES: 156 * 1. The allocated event channel is bound to the specified vcpu. The binding 157 * may not be changed. 158 */ 159struct evtchn_bind_ipi { 160 uint32_t vcpu; 161 /* OUT parameters. */ 162 evtchn_port_t port; 163}; 164typedef struct evtchn_bind_ipi evtchn_bind_ipi_t; 165 166/* 167 * EVTCHNOP_close: Close a local event channel <port>. If the channel is 168 * interdomain then the remote end is placed in the unbound state 169 * (EVTCHNSTAT_unbound), awaiting a new connection. 170 */ 171struct evtchn_close { 172 /* IN parameters. */ 173 evtchn_port_t port; 174}; 175typedef struct evtchn_close evtchn_close_t; 176 177/* 178 * EVTCHNOP_send: Send an event to the remote end of the channel whose local 179 * endpoint is <port>. 180 */ 181struct evtchn_send { 182 /* IN parameters. */ 183 evtchn_port_t port; 184}; 185typedef struct evtchn_send evtchn_send_t; 186 187/* 188 * EVTCHNOP_status: Get the current status of the communication channel which 189 * has an endpoint at <dom, port>. 190 * NOTES: 191 * 1. <dom> may be specified as DOMID_SELF. 192 * 2. Only a sufficiently-privileged domain may obtain the status of an event 193 * channel for which <dom> is not DOMID_SELF. 194 */ 195struct evtchn_status { 196 /* IN parameters */ 197 domid_t dom; 198 evtchn_port_t port; 199 /* OUT parameters */ 200#define EVTCHNSTAT_closed 0 /* Channel is not in use. */ 201#define EVTCHNSTAT_unbound 1 /* Channel is waiting interdom connection.*/ 202#define EVTCHNSTAT_interdomain 2 /* Channel is connected to remote domain. */ 203#define EVTCHNSTAT_pirq 3 /* Channel is bound to a phys IRQ line. */ 204#define EVTCHNSTAT_virq 4 /* Channel is bound to a virtual IRQ line */ 205#define EVTCHNSTAT_ipi 5 /* Channel is bound to a virtual IPI line */ 206 uint32_t status; 207 uint32_t vcpu; /* VCPU to which this channel is bound. */ 208 union { 209 struct { 210 domid_t dom; 211 } unbound; /* EVTCHNSTAT_unbound */ 212 struct { 213 domid_t dom; 214 evtchn_port_t port; 215 } interdomain; /* EVTCHNSTAT_interdomain */ 216 uint32_t pirq; /* EVTCHNSTAT_pirq */ 217 uint32_t virq; /* EVTCHNSTAT_virq */ 218 } u; 219}; 220typedef struct evtchn_status evtchn_status_t; 221 222/* 223 * EVTCHNOP_bind_vcpu: Specify which vcpu a channel should notify when an 224 * event is pending. 225 * NOTES: 226 * 1. IPI-bound channels always notify the vcpu specified at bind time. 227 * This binding cannot be changed. 228 * 2. Per-VCPU VIRQ channels always notify the vcpu specified at bind time. 229 * This binding cannot be changed. 230 * 3. All other channels notify vcpu0 by default. This default is set when 231 * the channel is allocated (a port that is freed and subsequently reused 232 * has its binding reset to vcpu0). 233 */ 234struct evtchn_bind_vcpu { 235 /* IN parameters. */ 236 evtchn_port_t port; 237 uint32_t vcpu; 238}; 239typedef struct evtchn_bind_vcpu evtchn_bind_vcpu_t; 240 241/* 242 * EVTCHNOP_unmask: Unmask the specified local event-channel port and deliver 243 * a notification to the appropriate VCPU if an event is pending. 244 */ 245struct evtchn_unmask { 246 /* IN parameters. */ 247 evtchn_port_t port; 248}; 249typedef struct evtchn_unmask evtchn_unmask_t; 250 251/* 252 * EVTCHNOP_reset: Close all event channels associated with specified domain. 253 * NOTES: 254 * 1. <dom> may be specified as DOMID_SELF. 255 * 2. Only a sufficiently-privileged domain may specify other than DOMID_SELF. 256 */ 257struct evtchn_reset { 258 /* IN parameters. */ 259 domid_t dom; 260}; 261typedef struct evtchn_reset evtchn_reset_t; 262 263/* 264 * ` enum neg_errnoval 265 * ` HYPERVISOR_event_channel_op_compat(struct evtchn_op *op) 266 * ` 267 * Superceded by new event_channel_op() hypercall since 0x00030202. 268 */ 269struct evtchn_op { 270 uint32_t cmd; /* enum event_channel_op */ 271 union { 272 struct evtchn_alloc_unbound alloc_unbound; 273 struct evtchn_bind_interdomain bind_interdomain; 274 struct evtchn_bind_virq bind_virq; 275 struct evtchn_bind_pirq bind_pirq; 276 struct evtchn_bind_ipi bind_ipi; 277 struct evtchn_close close; 278 struct evtchn_send send; 279 struct evtchn_status status; 280 struct evtchn_bind_vcpu bind_vcpu; 281 struct evtchn_unmask unmask; 282 } u; 283}; 284typedef struct evtchn_op evtchn_op_t; 285DEFINE_XEN_GUEST_HANDLE(evtchn_op_t); 286 287#endif /* __XEN_PUBLIC_EVENT_CHANNEL_H__ */ 288 289/* 290 * Local variables: 291 * mode: C 292 * c-set-style: "BSD" 293 * c-basic-offset: 4 294 * tab-width: 4 295 * indent-tabs-mode: nil 296 * End: 297 */ 298