1 /******************************************************************************
2 * Talks to Xen Store to figure out what devices we have.
4 * Copyright (C) 2009, 2010 Spectra Logic Corporation
5 * Copyright (C) 2008 Doug Rabson
6 * Copyright (C) 2005 Rusty Russell, IBM Corporation
7 * Copyright (C) 2005 Mike Wray, Hewlett-Packard
8 * Copyright (C) 2005 XenSource Ltd
10 * This file may be distributed separately from the Linux kernel, or
11 * incorporated into other software packages, subject to the following license:
13 * Permission is hereby granted, free of charge, to any person obtaining a copy
14 * of this source file (the "Software"), to deal in the Software without
15 * restriction, including without limitation the rights to use, copy, modify,
16 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
17 * and to permit persons to whom the Software is furnished to do so, subject to
18 * the following conditions:
20 * The above copyright notice and this permission notice shall be included in
21 * all copies or substantial portions of the Software.
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
25 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
26 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
33 * \file xenbusb_front.c
35 * XenBus management of the NewBus bus containing the frontend instances of
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/param.h>
43 #include <sys/kernel.h>
45 #include <sys/malloc.h>
46 #include <sys/module.h>
48 #include <sys/sysctl.h>
49 #include <sys/syslog.h>
50 #include <sys/systm.h>
52 #include <sys/taskqueue.h>
54 #include <machine/stdarg.h>
56 #include <xen/xen-os.h>
57 #include <xen/gnttab.h>
58 #include <xen/xenbus/xenbusvar.h>
59 #include <xen/xenbus/xenbusb.h>
61 /*------------------ Private Device Attachment Functions --------------------*/
63 * \brief Probe for the existance of the XenBus front bus.
65 * \param dev NewBus device_t for this XenBus front bus instance.
67 * \return Always returns 0 indicating success.
70 xenbusb_front_probe(device_t dev)
72 device_set_desc(dev, "Xen Frontend Devices");
78 * \brief Attach the XenBus front bus.
80 * \param dev NewBus device_t for this XenBus front bus instance.
82 * \return On success, 0. Otherwise an errno value indicating the
86 xenbusb_front_attach(device_t dev)
88 return (xenbusb_attach(dev, "device", /*id_components*/1));
92 * \brief Enumerate all devices of the given type on this bus.
94 * \param dev NewBus device_t for this XenBus front bus instance.
95 * \param type String indicating the device sub-tree (e.g. "vfb", "vif")
98 * \return On success, 0. Otherwise an errno value indicating the
101 * Devices that are found are entered into the NewBus hierarchy via
102 * xenbusb_add_device(). xenbusb_add_device() ignores duplicate detects
103 * and ignores duplicate devices, so it can be called unconditionally
104 * for any device found in the XenStore.
107 xenbusb_front_enumerate_type(device_t dev, const char *type)
109 struct xenbusb_softc *xbs;
111 unsigned int i, count;
114 xbs = device_get_softc(dev);
115 error = xs_directory(XST_NIL, xbs->xbs_node, type, &count, &dir);
118 for (i = 0; i < count; i++)
119 xenbusb_add_device(dev, type, dir[i]);
121 free(dir, M_XENSTORE);
127 * \brief Determine and store the XenStore path for the other end of
128 * a split device whose local end is represented by ivars.
130 * If successful, the xd_otherend_path field of the child's instance
131 * variables will be updated.
133 * \param dev NewBus device_t for this XenBus front bus instance.
134 * \param ivars Instance variables from the XenBus child device for
135 * which to perform this function.
137 * \return On success, 0. Otherwise an errno value indicating the
141 xenbusb_front_get_otherend_node(device_t dev, struct xenbus_device_ivars *ivars)
146 if (ivars->xd_otherend_path != NULL) {
147 free(ivars->xd_otherend_path, M_XENBUS);
148 ivars->xd_otherend_path = NULL;
151 error = xs_gather(XST_NIL, ivars->xd_node,
152 "backend-id", "%i", &ivars->xd_otherend_id,
153 "backend", NULL, &otherend_path,
157 ivars->xd_otherend_path = strdup(otherend_path, M_XENBUS);
158 ivars->xd_otherend_path_len = strlen(otherend_path);
159 free(otherend_path, M_XENSTORE);
164 /*-------------------- Private Device Attachment Data -----------------------*/
165 static device_method_t xenbusb_front_methods[] = {
166 /* Device interface */
167 DEVMETHOD(device_identify, xenbusb_identify),
168 DEVMETHOD(device_probe, xenbusb_front_probe),
169 DEVMETHOD(device_attach, xenbusb_front_attach),
170 DEVMETHOD(device_detach, bus_generic_detach),
171 DEVMETHOD(device_shutdown, bus_generic_shutdown),
172 DEVMETHOD(device_suspend, bus_generic_suspend),
173 DEVMETHOD(device_resume, xenbusb_resume),
176 DEVMETHOD(bus_print_child, xenbusb_print_child),
177 DEVMETHOD(bus_read_ivar, xenbusb_read_ivar),
178 DEVMETHOD(bus_write_ivar, xenbusb_write_ivar),
179 DEVMETHOD(bus_alloc_resource, bus_generic_alloc_resource),
180 DEVMETHOD(bus_release_resource, bus_generic_release_resource),
181 DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
182 DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
184 /* XenBus Bus Interface */
185 DEVMETHOD(xenbusb_enumerate_type, xenbusb_front_enumerate_type),
186 DEVMETHOD(xenbusb_get_otherend_node, xenbusb_front_get_otherend_node),
190 DEFINE_CLASS_0(xenbusb_front, xenbusb_front_driver, xenbusb_front_methods,
191 sizeof(struct xenbusb_softc));
192 devclass_t xenbusb_front_devclass;
194 DRIVER_MODULE(xenbusb_front, xenstore, xenbusb_front_driver,
195 xenbusb_front_devclass, 0, 0);