1 /******************************************************************************
4 * Talks to Xen Store to figure out what devices we have.
6 * Copyright (C) 2005 Rusty Russell, IBM Corporation
7 * Copyright (C) 2005 XenSource Ltd.
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation; or, when distributed
12 * separately from the Linux kernel or incorporated into other
13 * software packages, subject to the following license:
15 * Permission is hereby granted, free of charge, to any person obtaining a copy
16 * of this source file (the "Software"), to deal in the Software without
17 * restriction, including without limitation the rights to use, copy, modify,
18 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
19 * and to permit persons to whom the Software is furnished to do so, subject to
20 * the following conditions:
22 * The above copyright notice and this permission notice shall be included in
23 * all copies or substantial portions of the Software.
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
26 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
28 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
29 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
30 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
37 #include <linux/device.h>
38 #include <linux/notifier.h>
39 #include <linux/mutex.h>
40 #include <linux/export.h>
41 #include <linux/completion.h>
42 #include <linux/init.h>
43 #include <linux/slab.h>
44 #include <xen/interface/xen.h>
45 #include <xen/interface/grant_table.h>
46 #include <xen/interface/io/xenbus.h>
47 #include <xen/interface/io/xs_wire.h>
49 /* Register callback to watch this node. */
52 struct list_head list
;
54 /* Path being watched. */
57 /* Callback (executed in a process context with no locks held). */
58 void (*callback
)(struct xenbus_watch
*,
59 const char **vec
, unsigned int len
);
63 /* A xenbus device. */
64 struct xenbus_device
{
65 const char *devicetype
;
69 struct xenbus_watch otherend_watch
;
71 enum xenbus_state state
;
72 struct completion down
;
73 struct work_struct work
;
76 static inline struct xenbus_device
*to_xenbus_device(struct device
*dev
)
78 return container_of(dev
, struct xenbus_device
, dev
);
81 struct xenbus_device_id
83 /* .../device/<device_type>/<identifier> */
84 char devicetype
[32]; /* General class of device. */
87 /* A xenbus driver. */
88 struct xenbus_driver
{
89 const char *name
; /* defaults to ids[0].devicetype */
90 const struct xenbus_device_id
*ids
;
91 int (*probe
)(struct xenbus_device
*dev
,
92 const struct xenbus_device_id
*id
);
93 void (*otherend_changed
)(struct xenbus_device
*dev
,
94 enum xenbus_state backend_state
);
95 int (*remove
)(struct xenbus_device
*dev
);
96 int (*suspend
)(struct xenbus_device
*dev
);
97 int (*resume
)(struct xenbus_device
*dev
);
98 int (*uevent
)(struct xenbus_device
*, struct kobj_uevent_env
*);
99 struct device_driver driver
;
100 int (*read_otherend_details
)(struct xenbus_device
*dev
);
101 int (*is_ready
)(struct xenbus_device
*dev
);
104 static inline struct xenbus_driver
*to_xenbus_driver(struct device_driver
*drv
)
106 return container_of(drv
, struct xenbus_driver
, driver
);
109 int __must_check
__xenbus_register_frontend(struct xenbus_driver
*drv
,
110 struct module
*owner
,
111 const char *mod_name
);
112 int __must_check
__xenbus_register_backend(struct xenbus_driver
*drv
,
113 struct module
*owner
,
114 const char *mod_name
);
116 #define xenbus_register_frontend(drv) \
117 __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME)
118 #define xenbus_register_backend(drv) \
119 __xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME)
121 void xenbus_unregister_driver(struct xenbus_driver
*drv
);
123 struct xenbus_transaction
128 /* Nil transaction ID. */
129 #define XBT_NIL ((struct xenbus_transaction) { 0 })
131 char **xenbus_directory(struct xenbus_transaction t
,
132 const char *dir
, const char *node
, unsigned int *num
);
133 void *xenbus_read(struct xenbus_transaction t
,
134 const char *dir
, const char *node
, unsigned int *len
);
135 int xenbus_write(struct xenbus_transaction t
,
136 const char *dir
, const char *node
, const char *string
);
137 int xenbus_mkdir(struct xenbus_transaction t
,
138 const char *dir
, const char *node
);
139 int xenbus_exists(struct xenbus_transaction t
,
140 const char *dir
, const char *node
);
141 int xenbus_rm(struct xenbus_transaction t
, const char *dir
, const char *node
);
142 int xenbus_transaction_start(struct xenbus_transaction
*t
);
143 int xenbus_transaction_end(struct xenbus_transaction t
, int abort
);
145 /* Single read and scanf: returns -errno or num scanned if > 0. */
147 int xenbus_scanf(struct xenbus_transaction t
,
148 const char *dir
, const char *node
, const char *fmt
, ...);
150 /* Single printf and write: returns -errno or 0. */
152 int xenbus_printf(struct xenbus_transaction t
,
153 const char *dir
, const char *node
, const char *fmt
, ...);
155 /* Generic read function: NULL-terminated triples of name,
156 * sprintf-style type string, and pointer. Returns 0 or errno.*/
157 int xenbus_gather(struct xenbus_transaction t
, const char *dir
, ...);
159 /* notifer routines for when the xenstore comes up */
160 extern int xenstored_ready
;
161 int register_xenstore_notifier(struct notifier_block
*nb
);
162 void unregister_xenstore_notifier(struct notifier_block
*nb
);
164 int register_xenbus_watch(struct xenbus_watch
*watch
);
165 void unregister_xenbus_watch(struct xenbus_watch
*watch
);
166 void xs_suspend(void);
167 void xs_resume(void);
168 void xs_suspend_cancel(void);
170 /* Used by xenbus_dev to borrow kernel's store connection. */
171 void *xenbus_dev_request_and_reply(struct xsd_sockmsg
*msg
);
175 /* Prepare for domain suspend: then resume or cancel the suspend. */
176 void xenbus_suspend(void);
177 void xenbus_resume(void);
178 void xenbus_probe(struct work_struct
*);
179 void xenbus_suspend_cancel(void);
181 #define XENBUS_IS_ERR_READ(str) ({ \
182 if (!IS_ERR(str) && strlen(str) == 0) { \
184 str = ERR_PTR(-ERANGE); \
189 #define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
191 int xenbus_watch_path(struct xenbus_device
*dev
, const char *path
,
192 struct xenbus_watch
*watch
,
193 void (*callback
)(struct xenbus_watch
*,
194 const char **, unsigned int));
196 int xenbus_watch_pathfmt(struct xenbus_device
*dev
, struct xenbus_watch
*watch
,
197 void (*callback
)(struct xenbus_watch
*,
198 const char **, unsigned int),
199 const char *pathfmt
, ...);
201 int xenbus_switch_state(struct xenbus_device
*dev
, enum xenbus_state new_state
);
202 int xenbus_grant_ring(struct xenbus_device
*dev
, unsigned long ring_mfn
);
203 int xenbus_map_ring_valloc(struct xenbus_device
*dev
,
204 int gnt_ref
, void **vaddr
);
205 int xenbus_map_ring(struct xenbus_device
*dev
, int gnt_ref
,
206 grant_handle_t
*handle
, void *vaddr
);
208 int xenbus_unmap_ring_vfree(struct xenbus_device
*dev
, void *vaddr
);
209 int xenbus_unmap_ring(struct xenbus_device
*dev
,
210 grant_handle_t handle
, void *vaddr
);
212 int xenbus_alloc_evtchn(struct xenbus_device
*dev
, int *port
);
213 int xenbus_free_evtchn(struct xenbus_device
*dev
, int port
);
215 enum xenbus_state
xenbus_read_driver_state(const char *path
);
218 void xenbus_dev_error(struct xenbus_device
*dev
, int err
, const char *fmt
, ...);
220 void xenbus_dev_fatal(struct xenbus_device
*dev
, int err
, const char *fmt
, ...);
222 const char *xenbus_strstate(enum xenbus_state state
);
223 int xenbus_dev_is_online(struct xenbus_device
*dev
);
224 int xenbus_frontend_closed(struct xenbus_device
*dev
);
226 #endif /* _XEN_XENBUS_H */