--- /dev/null
+/******************************************************************************
+ * event_channel.h
+ *
+ * Event channels between domains.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (c) 2003-2004, K A Fraser.
+ */
+
+#ifndef __XEN_PUBLIC_EVENT_CHANNEL_H__
+#define __XEN_PUBLIC_EVENT_CHANNEL_H__
+
+FILE_LICENCE ( MIT );
+
+#include "xen.h"
+
+/*
+ * `incontents 150 evtchn Event Channels
+ *
+ * Event channels are the basic primitive provided by Xen for event
+ * notifications. An event is the Xen equivalent of a hardware
+ * interrupt. They essentially store one bit of information, the event
+ * of interest is signalled by transitioning this bit from 0 to 1.
+ *
+ * Notifications are received by a guest via an upcall from Xen,
+ * indicating when an event arrives (setting the bit). Further
+ * notifications are masked until the bit is cleared again (therefore,
+ * guests must check the value of the bit after re-enabling event
+ * delivery to ensure no missed notifications).
+ *
+ * Event notifications can be masked by setting a flag; this is
+ * equivalent to disabling interrupts and can be used to ensure
+ * atomicity of certain operations in the guest kernel.
+ *
+ * Event channels are represented by the evtchn_* fields in
+ * struct shared_info and struct vcpu_info.
+ */
+
+/*
+ * ` enum neg_errnoval
+ * ` HYPERVISOR_event_channel_op(enum event_channel_op cmd, void *args)
+ * `
+ * @cmd == EVTCHNOP_* (event-channel operation).
+ * @args == struct evtchn_* Operation-specific extra arguments (NULL if none).
+ */
+
+/* ` enum event_channel_op { // EVTCHNOP_* => struct evtchn_* */
+#define EVTCHNOP_bind_interdomain 0
+#define EVTCHNOP_bind_virq 1
+#define EVTCHNOP_bind_pirq 2
+#define EVTCHNOP_close 3
+#define EVTCHNOP_send 4
+#define EVTCHNOP_status 5
+#define EVTCHNOP_alloc_unbound 6
+#define EVTCHNOP_bind_ipi 7
+#define EVTCHNOP_bind_vcpu 8
+#define EVTCHNOP_unmask 9
+#define EVTCHNOP_reset 10
+#define EVTCHNOP_init_control 11
+#define EVTCHNOP_expand_array 12
+#define EVTCHNOP_set_priority 13
+/* ` } */
+
+typedef uint32_t evtchn_port_t;
+DEFINE_XEN_GUEST_HANDLE(evtchn_port_t);
+
+/*
+ * EVTCHNOP_alloc_unbound: Allocate a port in domain <dom> and mark as
+ * accepting interdomain bindings from domain <remote_dom>. A fresh port
+ * is allocated in <dom> and returned as <port>.
+ * NOTES:
+ * 1. If the caller is unprivileged then <dom> must be DOMID_SELF.
+ * 2. <rdom> may be DOMID_SELF, allowing loopback connections.
+ */
+struct evtchn_alloc_unbound {
+ /* IN parameters */
+ domid_t dom, remote_dom;
+ /* OUT parameters */
+ evtchn_port_t port;
+};
+typedef struct evtchn_alloc_unbound evtchn_alloc_unbound_t;
+
+/*
+ * EVTCHNOP_bind_interdomain: Construct an interdomain event channel between
+ * the calling domain and <remote_dom>. <remote_dom,remote_port> must identify
+ * a port that is unbound and marked as accepting bindings from the calling
+ * domain. A fresh port is allocated in the calling domain and returned as
+ * <local_port>.
+ *
+ * In case the peer domain has already tried to set our event channel
+ * pending, before it was bound, EVTCHNOP_bind_interdomain always sets
+ * the local event channel pending.
+ *
+ * The usual pattern of use, in the guest's upcall (or subsequent
+ * handler) is as follows: (Re-enable the event channel for subsequent
+ * signalling and then) check for the existence of whatever condition
+ * is being waited for by other means, and take whatever action is
+ * needed (if any).
+ *
+ * NOTES:
+ * 1. <remote_dom> may be DOMID_SELF, allowing loopback connections.
+ */
+struct evtchn_bind_interdomain {
+ /* IN parameters. */
+ domid_t remote_dom;
+ evtchn_port_t remote_port;
+ /* OUT parameters. */
+ evtchn_port_t local_port;
+};
+typedef struct evtchn_bind_interdomain evtchn_bind_interdomain_t;
+
+/*
+ * EVTCHNOP_bind_virq: Bind a local event channel to VIRQ <irq> on specified
+ * vcpu.
+ * NOTES:
+ * 1. Virtual IRQs are classified as per-vcpu or global. See the VIRQ list
+ * in xen.h for the classification of each VIRQ.
+ * 2. Global VIRQs must be allocated on VCPU0 but can subsequently be
+ * re-bound via EVTCHNOP_bind_vcpu.
+ * 3. Per-vcpu VIRQs may be bound to at most one event channel per vcpu.
+ * The allocated event channel is bound to the specified vcpu and the
+ * binding cannot be changed.
+ */
+struct evtchn_bind_virq {
+ /* IN parameters. */
+ uint32_t virq; /* enum virq */
+ uint32_t vcpu;
+ /* OUT parameters. */
+ evtchn_port_t port;
+};
+typedef struct evtchn_bind_virq evtchn_bind_virq_t;
+
+/*
+ * EVTCHNOP_bind_pirq: Bind a local event channel to a real IRQ (PIRQ <irq>).
+ * NOTES:
+ * 1. A physical IRQ may be bound to at most one event channel per domain.
+ * 2. Only a sufficiently-privileged domain may bind to a physical IRQ.
+ */
+struct evtchn_bind_pirq {
+ /* IN parameters. */
+ uint32_t pirq;
+#define BIND_PIRQ__WILL_SHARE 1
+ uint32_t flags; /* BIND_PIRQ__* */
+ /* OUT parameters. */
+ evtchn_port_t port;
+};
+typedef struct evtchn_bind_pirq evtchn_bind_pirq_t;
+
+/*
+ * EVTCHNOP_bind_ipi: Bind a local event channel to receive events.
+ * NOTES:
+ * 1. The allocated event channel is bound to the specified vcpu. The binding
+ * may not be changed.
+ */
+struct evtchn_bind_ipi {
+ uint32_t vcpu;
+ /* OUT parameters. */
+ evtchn_port_t port;
+};
+typedef struct evtchn_bind_ipi evtchn_bind_ipi_t;
+
+/*
+ * EVTCHNOP_close: Close a local event channel <port>. If the channel is
+ * interdomain then the remote end is placed in the unbound state
+ * (EVTCHNSTAT_unbound), awaiting a new connection.
+ */
+struct evtchn_close {
+ /* IN parameters. */
+ evtchn_port_t port;
+};
+typedef struct evtchn_close evtchn_close_t;
+
+/*
+ * EVTCHNOP_send: Send an event to the remote end of the channel whose local
+ * endpoint is <port>.
+ */
+struct evtchn_send {
+ /* IN parameters. */
+ evtchn_port_t port;
+};
+typedef struct evtchn_send evtchn_send_t;
+
+/*
+ * EVTCHNOP_status: Get the current status of the communication channel which
+ * has an endpoint at <dom, port>.
+ * NOTES:
+ * 1. <dom> may be specified as DOMID_SELF.
+ * 2. Only a sufficiently-privileged domain may obtain the status of an event
+ * channel for which <dom> is not DOMID_SELF.
+ */
+struct evtchn_status {
+ /* IN parameters */
+ domid_t dom;
+ evtchn_port_t port;
+ /* OUT parameters */
+#define EVTCHNSTAT_closed 0 /* Channel is not in use. */
+#define EVTCHNSTAT_unbound 1 /* Channel is waiting interdom connection.*/
+#define EVTCHNSTAT_interdomain 2 /* Channel is connected to remote domain. */
+#define EVTCHNSTAT_pirq 3 /* Channel is bound to a phys IRQ line. */
+#define EVTCHNSTAT_virq 4 /* Channel is bound to a virtual IRQ line */
+#define EVTCHNSTAT_ipi 5 /* Channel is bound to a virtual IPI line */
+ uint32_t status;
+ uint32_t vcpu; /* VCPU to which this channel is bound. */
+ union {
+ struct {
+ domid_t dom;
+ } unbound; /* EVTCHNSTAT_unbound */
+ struct {
+ domid_t dom;
+ evtchn_port_t port;
+ } interdomain; /* EVTCHNSTAT_interdomain */
+ uint32_t pirq; /* EVTCHNSTAT_pirq */
+ uint32_t virq; /* EVTCHNSTAT_virq */
+ } u;
+};
+typedef struct evtchn_status evtchn_status_t;
+
+/*
+ * EVTCHNOP_bind_vcpu: Specify which vcpu a channel should notify when an
+ * event is pending.
+ * NOTES:
+ * 1. IPI-bound channels always notify the vcpu specified at bind time.
+ * This binding cannot be changed.
+ * 2. Per-VCPU VIRQ channels always notify the vcpu specified at bind time.
+ * This binding cannot be changed.
+ * 3. All other channels notify vcpu0 by default. This default is set when
+ * the channel is allocated (a port that is freed and subsequently reused
+ * has its binding reset to vcpu0).
+ */
+struct evtchn_bind_vcpu {
+ /* IN parameters. */
+ evtchn_port_t port;
+ uint32_t vcpu;
+};
+typedef struct evtchn_bind_vcpu evtchn_bind_vcpu_t;
+
+/*
+ * EVTCHNOP_unmask: Unmask the specified local event-channel port and deliver
+ * a notification to the appropriate VCPU if an event is pending.
+ */
+struct evtchn_unmask {
+ /* IN parameters. */
+ evtchn_port_t port;
+};
+typedef struct evtchn_unmask evtchn_unmask_t;
+
+/*
+ * EVTCHNOP_reset: Close all event channels associated with specified domain.
+ * NOTES:
+ * 1. <dom> may be specified as DOMID_SELF.
+ * 2. Only a sufficiently-privileged domain may specify other than DOMID_SELF.
+ */
+struct evtchn_reset {
+ /* IN parameters. */
+ domid_t dom;
+};
+typedef struct evtchn_reset evtchn_reset_t;
+
+/*
+ * EVTCHNOP_init_control: initialize the control block for the FIFO ABI.
+ *
+ * Note: any events that are currently pending will not be resent and
+ * will be lost. Guests should call this before binding any event to
+ * avoid losing any events.
+ */
+struct evtchn_init_control {
+ /* IN parameters. */
+ uint64_t control_gfn;
+ uint32_t offset;
+ uint32_t vcpu;
+ /* OUT parameters. */
+ uint8_t link_bits;
+ uint8_t _pad[7];
+};
+typedef struct evtchn_init_control evtchn_init_control_t;
+
+/*
+ * EVTCHNOP_expand_array: add an additional page to the event array.
+ */
+struct evtchn_expand_array {
+ /* IN parameters. */
+ uint64_t array_gfn;
+};
+typedef struct evtchn_expand_array evtchn_expand_array_t;
+
+/*
+ * EVTCHNOP_set_priority: set the priority for an event channel.
+ */
+struct evtchn_set_priority {
+ /* IN parameters. */
+ uint32_t port;
+ uint32_t priority;
+};
+typedef struct evtchn_set_priority evtchn_set_priority_t;
+
+/*
+ * ` enum neg_errnoval
+ * ` HYPERVISOR_event_channel_op_compat(struct evtchn_op *op)
+ * `
+ * Superceded by new event_channel_op() hypercall since 0x00030202.
+ */
+struct evtchn_op {
+ uint32_t cmd; /* enum event_channel_op */
+ union {
+ struct evtchn_alloc_unbound alloc_unbound;
+ struct evtchn_bind_interdomain bind_interdomain;
+ struct evtchn_bind_virq bind_virq;
+ struct evtchn_bind_pirq bind_pirq;
+ struct evtchn_bind_ipi bind_ipi;
+ struct evtchn_close close;
+ struct evtchn_send send;
+ struct evtchn_status status;
+ struct evtchn_bind_vcpu bind_vcpu;
+ struct evtchn_unmask unmask;
+ } u;
+};
+typedef struct evtchn_op evtchn_op_t;
+DEFINE_XEN_GUEST_HANDLE(evtchn_op_t);
+
+/*
+ * 2-level ABI
+ */
+
+#define EVTCHN_2L_NR_CHANNELS (sizeof(xen_ulong_t) * sizeof(xen_ulong_t) * 64)
+
+/*
+ * FIFO ABI
+ */
+
+/* Events may have priorities from 0 (highest) to 15 (lowest). */
+#define EVTCHN_FIFO_PRIORITY_MAX 0
+#define EVTCHN_FIFO_PRIORITY_DEFAULT 7
+#define EVTCHN_FIFO_PRIORITY_MIN 15
+
+#define EVTCHN_FIFO_MAX_QUEUES (EVTCHN_FIFO_PRIORITY_MIN + 1)
+
+typedef uint32_t event_word_t;
+
+#define EVTCHN_FIFO_PENDING 31
+#define EVTCHN_FIFO_MASKED 30
+#define EVTCHN_FIFO_LINKED 29
+#define EVTCHN_FIFO_BUSY 28
+
+#define EVTCHN_FIFO_LINK_BITS 17
+#define EVTCHN_FIFO_LINK_MASK ((1 << EVTCHN_FIFO_LINK_BITS) - 1)
+
+#define EVTCHN_FIFO_NR_CHANNELS (1 << EVTCHN_FIFO_LINK_BITS)
+
+struct evtchn_fifo_control_block {
+ uint32_t ready;
+ uint32_t _rsvd;
+ uint32_t head[EVTCHN_FIFO_MAX_QUEUES];
+};
+typedef struct evtchn_fifo_control_block evtchn_fifo_control_block_t;
+
+#endif /* __XEN_PUBLIC_EVENT_CHANNEL_H__ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
Code Review / kvmfornfv.git / blobdiff