1/***************************************************************************** 2 * xenbus.h 3 * 4 * Xenbus protocol details. 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) 2005 XenSource Ltd. 25 */ 26 27#ifndef _XEN_PUBLIC_IO_XENBUS_H 28#define _XEN_PUBLIC_IO_XENBUS_H 29 30/* 31 * The state of either end of the Xenbus, i.e. the current communication 32 * status of initialisation across the bus. States here imply nothing about 33 * the state of the connection between the driver and the kernel's device 34 * layers. 35 */ 36enum xenbus_state { 37 XenbusStateUnknown = 0, 38 39 /* 40 * Initializing: Back-end is initializing. 41 */ 42 XenbusStateInitialising = 1, 43 44 /* 45 * InitWait: Finished early initialisation but waiting for information 46 * from the peer or hotplug scripts. 47 */ 48 XenbusStateInitWait = 2, 49 50 /* 51 * Initialised: Waiting for a connection from the peer. 52 */ 53 XenbusStateInitialised = 3, 54 55 /* 56 * Connected: The normal state for a front to backend connection. 57 */ 58 XenbusStateConnected = 4, 59 60 /* 61 * Closing: The device is being closed due to an error or an unplug event. 62 */ 63 XenbusStateClosing = 5, 64 65 /* 66 * Closed: No connection exists between front and back end. 67 * 68 * For backend devices with the "online" attribute, the front can 69 * request a reconnect at any time. To handle this transition 70 * gracefully, backend devices must reinitialize any XenStore data 71 * used to negotiate features with a peer before transitioning to 72 * the closed state. When a reconnect request occurs, the 73 * XenBus backend support code will automatically transition the 74 * backend device from Closed to InitWait, kicking off the ring 75 * and feature negotiation process. 76 */ 77 XenbusStateClosed = 6, 78 79 /* 80 * Reconfiguring: The device is being reconfigured. 81 */ 82 XenbusStateReconfiguring = 7, 83 84 XenbusStateReconfigured = 8 85}; 86typedef enum xenbus_state XenbusState; 87 88#endif /* _XEN_PUBLIC_IO_XENBUS_H */ 89 90/* 91 * Local variables: 92 * mode: C 93 * c-set-style: "BSD" 94 * c-basic-offset: 4 95 * tab-width: 4 96 * indent-tabs-mode: nil 97 * End: 98 */ 99