xref: /openbmc/linux/include/xen/interface/event_channel.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 /******************************************************************************
2  * event_channel.h
3  *
4  * Event channels between domains.
5  *
6  * Copyright (c) 2003-2004, K A Fraser.
7  */
8 
9 #ifndef __XEN_PUBLIC_EVENT_CHANNEL_H__
10 #define __XEN_PUBLIC_EVENT_CHANNEL_H__
11 
12 typedef uint32_t evtchn_port_t;
13 DEFINE_GUEST_HANDLE(evtchn_port_t);
14 
15 /*
16  * EVTCHNOP_alloc_unbound: Allocate a port in domain <dom> and mark as
17  * accepting interdomain bindings from domain <remote_dom>. A fresh port
18  * is allocated in <dom> and returned as <port>.
19  * NOTES:
20  *  1. If the caller is unprivileged then <dom> must be DOMID_SELF.
21  *  2. <rdom> may be DOMID_SELF, allowing loopback connections.
22  */
23 #define EVTCHNOP_alloc_unbound	  6
24 struct evtchn_alloc_unbound {
25 	/* IN parameters */
26 	domid_t dom, remote_dom;
27 	/* OUT parameters */
28 	evtchn_port_t port;
29 };
30 
31 /*
32  * EVTCHNOP_bind_interdomain: Construct an interdomain event channel between
33  * the calling domain and <remote_dom>. <remote_dom,remote_port> must identify
34  * a port that is unbound and marked as accepting bindings from the calling
35  * domain. A fresh port is allocated in the calling domain and returned as
36  * <local_port>.
37  * NOTES:
38  *  2. <remote_dom> may be DOMID_SELF, allowing loopback connections.
39  */
40 #define EVTCHNOP_bind_interdomain 0
41 struct evtchn_bind_interdomain {
42 	/* IN parameters. */
43 	domid_t remote_dom;
44 	evtchn_port_t remote_port;
45 	/* OUT parameters. */
46 	evtchn_port_t local_port;
47 };
48 
49 /*
50  * EVTCHNOP_bind_virq: Bind a local event channel to VIRQ <irq> on specified
51  * vcpu.
52  * NOTES:
53  *  1. A virtual IRQ may be bound to at most one event channel per vcpu.
54  *  2. The allocated event channel is bound to the specified vcpu. The binding
55  *     may not be changed.
56  */
57 #define EVTCHNOP_bind_virq	  1
58 struct evtchn_bind_virq {
59 	/* IN parameters. */
60 	uint32_t virq;
61 	uint32_t vcpu;
62 	/* OUT parameters. */
63 	evtchn_port_t port;
64 };
65 
66 /*
67  * EVTCHNOP_bind_pirq: Bind a local event channel to PIRQ <irq>.
68  * NOTES:
69  *  1. A physical IRQ may be bound to at most one event channel per domain.
70  *  2. Only a sufficiently-privileged domain may bind to a physical IRQ.
71  */
72 #define EVTCHNOP_bind_pirq	  2
73 struct evtchn_bind_pirq {
74 	/* IN parameters. */
75 	uint32_t pirq;
76 #define BIND_PIRQ__WILL_SHARE 1
77 	uint32_t flags; /* BIND_PIRQ__* */
78 	/* OUT parameters. */
79 	evtchn_port_t port;
80 };
81 
82 /*
83  * EVTCHNOP_bind_ipi: Bind a local event channel to receive events.
84  * NOTES:
85  *  1. The allocated event channel is bound to the specified vcpu. The binding
86  *     may not be changed.
87  */
88 #define EVTCHNOP_bind_ipi	  7
89 struct evtchn_bind_ipi {
90 	uint32_t vcpu;
91 	/* OUT parameters. */
92 	evtchn_port_t port;
93 };
94 
95 /*
96  * EVTCHNOP_close: Close a local event channel <port>. If the channel is
97  * interdomain then the remote end is placed in the unbound state
98  * (EVTCHNSTAT_unbound), awaiting a new connection.
99  */
100 #define EVTCHNOP_close		  3
101 struct evtchn_close {
102 	/* IN parameters. */
103 	evtchn_port_t port;
104 };
105 
106 /*
107  * EVTCHNOP_send: Send an event to the remote end of the channel whose local
108  * endpoint is <port>.
109  */
110 #define EVTCHNOP_send		  4
111 struct evtchn_send {
112 	/* IN parameters. */
113 	evtchn_port_t port;
114 };
115 
116 /*
117  * EVTCHNOP_status: Get the current status of the communication channel which
118  * has an endpoint at <dom, port>.
119  * NOTES:
120  *  1. <dom> may be specified as DOMID_SELF.
121  *  2. Only a sufficiently-privileged domain may obtain the status of an event
122  *     channel for which <dom> is not DOMID_SELF.
123  */
124 #define EVTCHNOP_status		  5
125 struct evtchn_status {
126 	/* IN parameters */
127 	domid_t  dom;
128 	evtchn_port_t port;
129 	/* OUT parameters */
130 #define EVTCHNSTAT_closed	0  /* Channel is not in use.		     */
131 #define EVTCHNSTAT_unbound	1  /* Channel is waiting interdom connection.*/
132 #define EVTCHNSTAT_interdomain	2  /* Channel is connected to remote domain. */
133 #define EVTCHNSTAT_pirq		3  /* Channel is bound to a phys IRQ line.   */
134 #define EVTCHNSTAT_virq		4  /* Channel is bound to a virtual IRQ line */
135 #define EVTCHNSTAT_ipi		5  /* Channel is bound to a virtual IPI line */
136 	uint32_t status;
137 	uint32_t vcpu;		   /* VCPU to which this channel is bound.   */
138 	union {
139 		struct {
140 			domid_t dom;
141 		} unbound; /* EVTCHNSTAT_unbound */
142 		struct {
143 			domid_t dom;
144 			evtchn_port_t port;
145 		} interdomain; /* EVTCHNSTAT_interdomain */
146 		uint32_t pirq;	    /* EVTCHNSTAT_pirq	      */
147 		uint32_t virq;	    /* EVTCHNSTAT_virq	      */
148 	} u;
149 };
150 
151 /*
152  * EVTCHNOP_bind_vcpu: Specify which vcpu a channel should notify when an
153  * event is pending.
154  * NOTES:
155  *  1. IPI- and VIRQ-bound channels always notify the vcpu that initialised
156  *     the binding. This binding cannot be changed.
157  *  2. All other channels notify vcpu0 by default. This default is set when
158  *     the channel is allocated (a port that is freed and subsequently reused
159  *     has its binding reset to vcpu0).
160  */
161 #define EVTCHNOP_bind_vcpu	  8
162 struct evtchn_bind_vcpu {
163 	/* IN parameters. */
164 	evtchn_port_t port;
165 	uint32_t vcpu;
166 };
167 
168 /*
169  * EVTCHNOP_unmask: Unmask the specified local event-channel port and deliver
170  * a notification to the appropriate VCPU if an event is pending.
171  */
172 #define EVTCHNOP_unmask		  9
173 struct evtchn_unmask {
174 	/* IN parameters. */
175 	evtchn_port_t port;
176 };
177 
178 struct evtchn_op {
179 	uint32_t cmd; /* EVTCHNOP_* */
180 	union {
181 		struct evtchn_alloc_unbound    alloc_unbound;
182 		struct evtchn_bind_interdomain bind_interdomain;
183 		struct evtchn_bind_virq	       bind_virq;
184 		struct evtchn_bind_pirq	       bind_pirq;
185 		struct evtchn_bind_ipi	       bind_ipi;
186 		struct evtchn_close	       close;
187 		struct evtchn_send	       send;
188 		struct evtchn_status	       status;
189 		struct evtchn_bind_vcpu	       bind_vcpu;
190 		struct evtchn_unmask	       unmask;
191 	} u;
192 };
193 DEFINE_GUEST_HANDLE_STRUCT(evtchn_op);
194 
195 #endif /* __XEN_PUBLIC_EVENT_CHANNEL_H__ */
196