audk/OvmfPkg/Include/Protocol/XenBus.h

417 lines
12 KiB
C

/** @file
XenBus protocol to be used between the XenBus bus driver and Xen PV devices.
DISCLAIMER: the XENBUS_PROTOCOL introduced here is a work in progress, and
should not be used outside of the EDK II tree.
This protocol provide the necessary for a Xen PV driver frontend to
communicate with the bus driver, and perform several task to
initialize/shutdown a PV device and perform IO with a PV backend.
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 __PROTOCOL_XENBUS_H__
#define __PROTOCOL_XENBUS_H__
#define XENBUS_PROTOCOL_GUID \
{0x3d3ca290, 0xb9a5, 0x11e3, {0xb7, 0x5d, 0xb8, 0xac, 0x6f, 0x7d, 0x65, 0xe6}}
///
/// Forward declaration
///
typedef struct _XENBUS_PROTOCOL XENBUS_PROTOCOL;
typedef enum xenbus_state XenBusState;
typedef struct
{
UINT32 Id;
} XENSTORE_TRANSACTION;
#define XST_NIL ((XENSTORE_TRANSACTION *) NULL)
typedef enum {
XENSTORE_STATUS_SUCCESS = 0,
XENSTORE_STATUS_FAIL,
XENSTORE_STATUS_EINVAL,
XENSTORE_STATUS_EACCES,
XENSTORE_STATUS_EEXIST,
XENSTORE_STATUS_EISDIR,
XENSTORE_STATUS_ENOENT,
XENSTORE_STATUS_ENOMEM,
XENSTORE_STATUS_ENOSPC,
XENSTORE_STATUS_EIO,
XENSTORE_STATUS_ENOTEMPTY,
XENSTORE_STATUS_ENOSYS,
XENSTORE_STATUS_EROFS,
XENSTORE_STATUS_EBUSY,
XENSTORE_STATUS_EAGAIN,
XENSTORE_STATUS_EISCONN,
XENSTORE_STATUS_E2BIG
} XENSTORE_STATUS;
#include <IndustryStandard/Xen/grant_table.h>
#include <IndustryStandard/Xen/event_channel.h>
///
/// Function prototypes
///
/**
Get the contents of the node Node of the PV device. Returns the contents in
*Result which should be freed after use.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The XenStore transaction covering this request.
@param Node The basename of the file to read.
@param Result The returned contents from this file.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
@note The results buffer is malloced and should be free'd by the
caller.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_XS_READ)(
IN XENBUS_PROTOCOL *This,
IN CONST XENSTORE_TRANSACTION *Transaction,
IN CONST CHAR8 *Node,
OUT VOID **Result
);
/**
Get the contents of the node Node of the PV device's backend. Returns the
contents in *Result which should be freed after use.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The XenStore transaction covering this request.
@param Node The basename of the file to read.
@param Result The returned contents from this file.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
@note The results buffer is malloced and should be free'd by the
caller.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_XS_BACKEND_READ)(
IN XENBUS_PROTOCOL *This,
IN CONST XENSTORE_TRANSACTION *Transaction,
IN CONST CHAR8 *Node,
OUT VOID **Result
);
/**
Print formatted write to a XenStore node.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The XenStore transaction covering this request.
@param Directory The dirname of the path to read.
@param Node The basename of the path to read.
@param Format AsciiSPrint format string followed by a variable number
of arguments.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of write failure.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_XS_PRINTF) (
IN XENBUS_PROTOCOL *This,
IN CONST XENSTORE_TRANSACTION *Transaction,
IN CONST CHAR8 *Directory,
IN CONST CHAR8 *Node,
IN CONST CHAR8 *Format,
...
);
/**
Remove a node or directory (directories must be empty) of the PV driver's
subdirectory.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The XenStore transaction covering this request.
@param Node The basename of the node to remove.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_XS_REMOVE) (
IN XENBUS_PROTOCOL *This,
IN CONST XENSTORE_TRANSACTION *Transaction,
IN CONST CHAR8 *Node
);
/**
Start a transaction.
Changes by others will not be seen during the lifetime of this
transaction, and changes will not be visible to others until it
is committed (XsTransactionEnd).
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The returned transaction.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_XS_TRANSACTION_START)(
IN XENBUS_PROTOCOL *This,
OUT XENSTORE_TRANSACTION *Transaction
);
/**
End a transaction.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The transaction to end/commit.
@param Abort If TRUE, the transaction is discarded
instead of committed.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_XS_TRANSACTION_END) (
IN XENBUS_PROTOCOL *This,
IN CONST XENSTORE_TRANSACTION *Transaction,
IN BOOLEAN Abort
);
/**
Set a new state for the frontend of the PV driver.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Transaction The transaction to end/commit.
@param State The new state to apply.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_SET_STATE)(
IN XENBUS_PROTOCOL *This,
IN CONST XENSTORE_TRANSACTION *Transaction,
IN XenBusState State
);
/**
Grant access to the page Frame to the domain DomainId.
@param This A pointer to XENBUS_PROTOCOL instance.
@param DomainId ID of the domain to grant acces to.
@param Frame Frame Number of the page to grant access to.
@param ReadOnly Provide read-only or read-write access.
@param RefPtr Reference number of the grant will be writen to this pointer.
**/
typedef
EFI_STATUS
(EFIAPI *XENBUS_GRANT_ACCESS)(
IN XENBUS_PROTOCOL *This,
IN domid_t DomainId,
IN UINTN Frame,
IN BOOLEAN ReadOnly,
OUT grant_ref_t *refp
);
/**
End access to grant Ref, previously return by XenBusGrantAccess.
@param This A pointer to XENBUS_PROTOCOL instance.
@param Ref Reference numeber of a grant previously returned by
XenBusGrantAccess.
**/
typedef
EFI_STATUS
(EFIAPI *XENBUS_GRANT_END_ACCESS)(
IN XENBUS_PROTOCOL *This,
IN grant_ref_t Ref
);
/**
Allocate a port that can be bind from domain DomainId.
@param This A pointer to the XENBUS_PROTOCOL.
@param DomainId The domain ID that can bind the newly allocated port.
@param Port A pointer to a evtchn_port_t that will contain the newly
allocated port.
@retval UINT32 The return value from the hypercall, 0 if success.
**/
typedef
UINT32
(EFIAPI *XENBUS_EVENT_CHANNEL_ALLOCATE) (
IN XENBUS_PROTOCOL *This,
IN domid_t DomainId,
OUT evtchn_port_t *Port
);
/**
Send an event to the remote end of the channel whose local endpoint is Port.
@param This A pointer to the XENBUS_PROTOCOL.
@param Port Local port to the the event from.
@retval UINT32 The return value from the hypercall, 0 if success.
**/
typedef
UINT32
(EFIAPI *XENBUS_EVENT_CHANNEL_NOTIFY) (
IN XENBUS_PROTOCOL *This,
IN evtchn_port_t Port
);
/**
Close a local event channel Port.
@param This A pointer to the XENBUS_PROTOCOL.
@param Port The event channel to close.
@retval UINT32 The return value from the hypercall, 0 if success.
**/
typedef
UINT32
(EFIAPI *XENBUS_EVENT_CHANNEL_CLOSE) (
IN XENBUS_PROTOCOL *This,
IN evtchn_port_t Port
);
/**
Register a XenStore watch.
XenStore watches allow a client to wait for changes to an object in the
XenStore.
@param This A pointer to the XENBUS_PROTOCOL.
@param Node The basename of the path to watch.
@param Token A token.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of write failure. EEXIST errors from the
XenStore are supressed, allowing multiple, physically different,
xenbus_watch objects, to watch the same path in the XenStore.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_REGISTER_WATCH) (
IN XENBUS_PROTOCOL *This,
IN CONST CHAR8 *Node,
OUT VOID **Token
);
/**
Register a XenStore watch on a backend's node.
XenStore watches allow a client to wait for changes to an object in the
XenStore.
@param This A pointer to the XENBUS_PROTOCOL.
@param Node The basename of the path to watch.
@param Token A token.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of write failure. EEXIST errors from the
XenStore are supressed, allowing multiple, physically different,
xenbus_watch objects, to watch the same path in the XenStore.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_REGISTER_WATCH_BACKEND) (
IN XENBUS_PROTOCOL *This,
IN CONST CHAR8 *Node,
OUT VOID **Token
);
/**
Unregister a XenStore watch.
@param This A pointer to the XENBUS_PROTOCOL.
@param Token An token previously returned by a successful
call to RegisterWatch ().
**/
typedef
VOID
(EFIAPI *XENBUS_UNREGISTER_WATCH) (
IN XENBUS_PROTOCOL *This,
IN VOID *Token
);
/**
Block until the node watch by Token change.
@param This A pointer to the XENBUS_PROTOCOL.
@param Token An token previously returned by a successful
call to RegisterWatch or RegisterWatchBackend.
@return On success, XENSTORE_STATUS_SUCCESS. Otherwise an errno value
indicating the type of failure.
**/
typedef
XENSTORE_STATUS
(EFIAPI *XENBUS_WAIT_FOR_WATCH) (
IN XENBUS_PROTOCOL *This,
IN VOID *Token
);
///
/// Protocol structure
///
/// DISCLAIMER: the XENBUS_PROTOCOL introduced here is a work in progress, and
/// should not be used outside of the EDK II tree.
///
struct _XENBUS_PROTOCOL {
XENBUS_XS_READ XsRead;
XENBUS_XS_BACKEND_READ XsBackendRead;
XENBUS_XS_PRINTF XsPrintf;
XENBUS_XS_REMOVE XsRemove;
XENBUS_XS_TRANSACTION_START XsTransactionStart;
XENBUS_XS_TRANSACTION_END XsTransactionEnd;
XENBUS_SET_STATE SetState;
XENBUS_GRANT_ACCESS GrantAccess;
XENBUS_GRANT_END_ACCESS GrantEndAccess;
XENBUS_EVENT_CHANNEL_ALLOCATE EventChannelAllocate;
XENBUS_EVENT_CHANNEL_NOTIFY EventChannelNotify;
XENBUS_EVENT_CHANNEL_CLOSE EventChannelClose;
XENBUS_REGISTER_WATCH RegisterWatch;
XENBUS_REGISTER_WATCH_BACKEND RegisterWatchBackend;
XENBUS_UNREGISTER_WATCH UnregisterWatch;
XENBUS_WAIT_FOR_WATCH WaitForWatch;
//
// Protocol data fields
//
CONST CHAR8 *Type;
UINT16 DeviceId;
CONST CHAR8 *Node;
CONST CHAR8 *Backend;
};
extern EFI_GUID gXenBusProtocolGuid;
#endif