1 /******************************************************************************
2 * Copyright (C) 2005 Rusty Russell, IBM Corporation
3 * Copyright (C) 2005 XenSource Ltd.
5 * This file may be distributed separately from the Linux kernel, or
6 * incorporated into other software packages, subject to the following license:
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this source file (the "Software"), to deal in the Software without
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12 * and to permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
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18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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23 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
32 * \brief Datastructures and function declarations for usedby device
33 * drivers operating on the XenBus.
36 #ifndef _XEN_XENBUS_XENBUSVAR_H
37 #define _XEN_XENBUS_XENBUSVAR_H
39 #include <sys/queue.h>
41 #include <sys/eventhandler.h>
42 #include <sys/malloc.h>
45 #include <machine/stdarg.h>
47 #include <xen/xen-os.h>
48 #include <xen/interface/grant_table.h>
49 #include <xen/interface/io/xenbus.h>
50 #include <xen/interface/io/xs_wire.h>
52 #include <xen/xenstore/xenstorevar.h>
54 /* XenBus allocations including XenStore data returned to clients. */
55 MALLOC_DECLARE(M_XENBUS);
59 * Path of this device node.
64 * The device type (e.g. vif, vbd).
69 * The state of this device (not the otherend's state).
74 * Domain ID of the other end device.
76 XENBUS_IVAR_OTHEREND_ID,
79 * Path of the other end device.
81 XENBUS_IVAR_OTHEREND_PATH
85 * Simplified accessors for xenbus devices:
90 * xenbus_get_otherend_id
91 * xenbus_get_otherend_path
93 #define XENBUS_ACCESSOR(var, ivar, type) \
94 __BUS_ACCESSOR(xenbus, var, XENBUS, ivar, type)
96 XENBUS_ACCESSOR(node, NODE, const char *)
97 XENBUS_ACCESSOR(type, TYPE, const char *)
98 XENBUS_ACCESSOR(state, STATE, enum xenbus_state)
99 XENBUS_ACCESSOR(otherend_id, OTHEREND_ID, int)
100 XENBUS_ACCESSOR(otherend_path, OTHEREND_PATH, const char *)
103 * Return the state of a XenBus device.
105 * \param path The root XenStore path for the device.
107 * \return The current state of the device or XenbusStateClosed if no
110 XenbusState xenbus_read_driver_state(const char *path);
113 * Return the state of the "other end" (peer) of a XenBus device.
115 * \param dev The XenBus device whose peer to query.
117 * \return The current state of the peer device or XenbusStateClosed if no
120 static inline XenbusState
121 xenbus_get_otherend_state(device_t dev)
123 return (xenbus_read_driver_state(xenbus_get_otherend_path(dev)));
127 * Grant access to the given ring_mfn to the peer of the given device.
129 * \param dev The device granting access to the ring page.
130 * \param ring_mfn The guest machine page number of the page to grant
131 * peer access rights.
132 * \param refp[out] The grant reference for the page.
134 * \return On success, 0. Otherwise an errno value indicating the
137 * A successful call to xenbus_grant_ring should be paired with a call
138 * to gnttab_end_foreign_access() when foregn access to this page is no
141 * \note On error, \a dev will be switched to the XenbusStateClosing
142 * state and the returned error is saved in the per-device error node
143 * for \a dev in the XenStore.
145 int xenbus_grant_ring(device_t dev, unsigned long ring_mfn, grant_ref_t *refp);
148 * Record the given errno, along with the given, printf-style, formatted
149 * message in dev's device specific error node in the XenStore.
151 * \param dev The device which encountered the error.
152 * \param err The errno value corresponding to the error.
153 * \param fmt Printf format string followed by a variable number of
156 void xenbus_dev_error(device_t dev, int err, const char *fmt, ...)
157 __attribute__((format(printf, 3, 4)));
160 * va_list version of xenbus_dev_error().
162 * \param dev The device which encountered the error.
163 * \param err The errno value corresponding to the error.
164 * \param fmt Printf format string.
165 * \param ap Va_list of printf arguments.
167 void xenbus_dev_verror(device_t dev, int err, const char *fmt, va_list ap)
168 __attribute__((format(printf, 3, 0)));
171 * Equivalent to xenbus_dev_error(), followed by
172 * xenbus_set_state(dev, XenbusStateClosing).
174 * \param dev The device which encountered the error.
175 * \param err The errno value corresponding to the error.
176 * \param fmt Printf format string followed by a variable number of
179 void xenbus_dev_fatal(device_t dev, int err, const char *fmt, ...)
180 __attribute__((format(printf, 3, 4)));
183 * va_list version of xenbus_dev_fatal().
185 * \param dev The device which encountered the error.
186 * \param err The errno value corresponding to the error.
187 * \param fmt Printf format string.
188 * \param ap Va_list of printf arguments.
190 void xenbus_dev_vfatal(device_t dev, int err, const char *fmt, va_list)
191 __attribute__((format(printf, 3, 0)));
194 * Convert a member of the xenbus_state enum into an ASCII string.
196 * /param state The XenBus state to lookup.
198 * /return A string representing state or, for unrecognized states,
199 * the string "Unknown".
201 const char *xenbus_strstate(enum xenbus_state state);
204 * Return the value of a XenBus device's "online" node within the XenStore.
206 * \param dev The XenBus device to query.
208 * \return The value of the "online" node for the device. If the node
209 * does not exist, 0 (offline) is returned.
211 int xenbus_dev_is_online(device_t dev);
214 * Default callback invoked when a change to the local XenStore sub-tree
215 * for a device is modified.
217 * \param dev The XenBus device whose tree was modified.
218 * \param path The tree relative sub-path to the modified node. The empty
219 * string indicates the root of the tree was destroyed.
221 void xenbus_localend_changed(device_t dev, const char *path);
223 #include "xenbus_if.h"
225 #endif /* _XEN_XENBUS_XENBUSVAR_H */