From f1259bba3647beb30b7c5e2e7dbe6ba060814912 Mon Sep 17 00:00:00 2001 From: Anthony PERARD Date: Wed, 29 Oct 2014 06:50:24 +0000 Subject: OvmfPkg/XenBusDxe: Add Event Channel Notify. This first function is used to notify the other side that there is something to do. The other side is another Xen domain. Change in V4: - Replace the license by the commonly used file header text. Change in V3: - Return error code from hypercall instead of ASSERT for XenEventChannelNotify - moving event_channel.h to this patch. Change in V2: - file header - coding style - adding comment to functions - Licenses License: This patch adds event_channel.h which is under MIT licence. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Anthony PERARD Acked-by: Jordan Justen git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16265 6f19259b-4bc3-4df7-8a09-765794883524 --- .../Include/IndustryStandard/Xen/event_channel.h | 118 +++++++++++++++++++++ OvmfPkg/XenBusDxe/EventChannel.c | 33 ++++++ OvmfPkg/XenBusDxe/EventChannel.h | 36 +++++++ OvmfPkg/XenBusDxe/XenBusDxe.inf | 2 + 4 files changed, 189 insertions(+) create mode 100644 OvmfPkg/Include/IndustryStandard/Xen/event_channel.h create mode 100644 OvmfPkg/XenBusDxe/EventChannel.c create mode 100644 OvmfPkg/XenBusDxe/EventChannel.h diff --git a/OvmfPkg/Include/IndustryStandard/Xen/event_channel.h b/OvmfPkg/Include/IndustryStandard/Xen/event_channel.h new file mode 100644 index 0000000000..6377ce7b1a --- /dev/null +++ b/OvmfPkg/Include/IndustryStandard/Xen/event_channel.h @@ -0,0 +1,118 @@ +/****************************************************************************** + * 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__ + +#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_close 3 +#define EVTCHNOP_send 4 +#define EVTCHNOP_alloc_unbound 6 +/* ` } */ + +typedef UINT32 evtchn_port_t; +DEFINE_XEN_GUEST_HANDLE(evtchn_port_t); + +/* + * EVTCHNOP_alloc_unbound: Allocate a port in domain and mark as + * accepting interdomain bindings from domain . A fresh port + * is allocated in and returned as . + * NOTES: + * 1. If the caller is unprivileged then must be DOMID_SELF. + * 2. 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_close: Close a local event channel . 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 . + */ +struct evtchn_send { + /* IN parameters. */ + evtchn_port_t port; +}; +typedef struct evtchn_send evtchn_send_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: + */ diff --git a/OvmfPkg/XenBusDxe/EventChannel.c b/OvmfPkg/XenBusDxe/EventChannel.c new file mode 100644 index 0000000000..c4076c49ea --- /dev/null +++ b/OvmfPkg/XenBusDxe/EventChannel.c @@ -0,0 +1,33 @@ +/** @file + Event Channel function implementation. + + Event channel are use to notify of an event that happend in a shared + structure for example. + + Copyright (C) 2014, Citrix Ltd. + + This program and the accompanying materials + are licensed and made available under the terms and conditions of the BSD License + which accompanies this distribution. The full text of the license may be found at + http://opensource.org/licenses/bsd-license.php + + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ +#include "EventChannel.h" +#include "XenHypercall.h" + +UINT32 +XenEventChannelNotify ( + IN XENBUS_DEVICE *Dev, + IN evtchn_port_t Port + ) +{ + INTN ReturnCode; + evtchn_send_t Send; + + Send.port = Port; + ReturnCode = XenHypercallEventChannelOp (Dev, EVTCHNOP_send, &Send); + return ReturnCode; +} diff --git a/OvmfPkg/XenBusDxe/EventChannel.h b/OvmfPkg/XenBusDxe/EventChannel.h new file mode 100644 index 0000000000..5f3171d7ca --- /dev/null +++ b/OvmfPkg/XenBusDxe/EventChannel.h @@ -0,0 +1,36 @@ +/** @file + Event Channel function declaration. + + Copyright (C) 2014, Citrix Ltd. + + This program and the accompanying materials + are licensed and made available under the terms and conditions of the BSD License + which accompanies this distribution. The full text of the license may be found at + http://opensource.org/licenses/bsd-license.php + + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ +#ifndef __XENBUS_EVENT_CHANNEL_H +#define __XENBUS_EVENT_CHANNEL_H + +#include "XenBusDxe.h" + +#include + +/** + Send an event to the remote end of the channel whose local endpoint is Port. + + @param Dev A pointer to XENBUS_DEVICE. + @param Port The port to notify. + + @return Return 0 on success, or return the errno code from the hypercall. +**/ +UINT32 +XenEventChannelNotify ( + IN XENBUS_DEVICE *Dev, + IN evtchn_port_t Port + ); + +#endif diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.inf b/OvmfPkg/XenBusDxe/XenBusDxe.inf index 080e55a9bb..0af1946e26 100644 --- a/OvmfPkg/XenBusDxe/XenBusDxe.inf +++ b/OvmfPkg/XenBusDxe/XenBusDxe.inf @@ -40,6 +40,8 @@ InterlockedCompareExchange16.h GrantTable.c GrantTable.h + EventChannel.c + EventChannel.h [Sources.IA32] Ia32/hypercall.S -- cgit v1.2.3