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1/******************************************************************************
2 * xenbus.h
3 *
4 * Talks to Xen Store to figure out what devices we have.
5 *
6 * Copyright (C) 2005 Rusty Russell, IBM Corporation
7 * Copyright (C) 2005 XenSource Ltd.
8 *
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:
14 *
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:
21 *
22 * The above copyright notice and this permission notice shall be included in
23 * all copies or substantial portions of the Software.
24 *
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
31 * IN THE SOFTWARE.
32 */
33
34#ifndef _XEN_XENBUS_H
35#define _XEN_XENBUS_H
36
37#include <linux/device.h>
38#include <linux/notifier.h>
39#include <linux/mutex.h>
40#include <linux/completion.h>
41#include <linux/init.h>
42#include <linux/slab.h>
43#include <xen/interface/xen.h>
44#include <xen/interface/grant_table.h>
45#include <xen/interface/io/xenbus.h>
46#include <xen/interface/io/xs_wire.h>
47
48/* Register callback to watch this node. */
49struct xenbus_watch
50{
51 struct list_head list;
52
53 /* Path being watched. */
54 const char *node;
55
56 /* Callback (executed in a process context with no locks held). */
57 void (*callback)(struct xenbus_watch *,
58 const char **vec, unsigned int len);
59};
60
61
62/* A xenbus device. */
63struct xenbus_device {
64 const char *devicetype;
65 const char *nodename;
66 const char *otherend;
67 int otherend_id;
68 struct xenbus_watch otherend_watch;
69 struct device dev;
70 enum xenbus_state state;
71 struct completion down;
72};
73
74static inline struct xenbus_device *to_xenbus_device(struct device *dev)
75{
76 return container_of(dev, struct xenbus_device, dev);
77}
78
79struct xenbus_device_id
80{
81 /* .../device/<device_type>/<identifier> */
82 char devicetype[32]; /* General class of device. */
83};
84
85/* A xenbus driver. */
86struct xenbus_driver {
87 char *name;
88 struct module *owner;
89 const struct xenbus_device_id *ids;
90 int (*probe)(struct xenbus_device *dev,
91 const struct xenbus_device_id *id);
92 void (*otherend_changed)(struct xenbus_device *dev,
93 enum xenbus_state backend_state);
94 int (*remove)(struct xenbus_device *dev);
95 int (*suspend)(struct xenbus_device *dev);
96 int (*resume)(struct xenbus_device *dev);
97 int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
98 struct device_driver driver;
99 int (*read_otherend_details)(struct xenbus_device *dev);
100 int (*is_ready)(struct xenbus_device *dev);
101};
102
103static inline struct xenbus_driver *to_xenbus_driver(struct device_driver *drv)
104{
105 return container_of(drv, struct xenbus_driver, driver);
106}
107
108int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
109 struct module *owner,
110 const char *mod_name);
111
112static inline int __must_check
113xenbus_register_frontend(struct xenbus_driver *drv)
114{
115 WARN_ON(drv->owner != THIS_MODULE);
116 return __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME);
117}
118
119int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
120 struct module *owner,
121 const char *mod_name);
122static inline int __must_check
123xenbus_register_backend(struct xenbus_driver *drv)
124{
125 WARN_ON(drv->owner != THIS_MODULE);
126 return __xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME);
127}
128
129void xenbus_unregister_driver(struct xenbus_driver *drv);
130
131struct xenbus_transaction
132{
133 u32 id;
134};
135
136/* Nil transaction ID. */
137#define XBT_NIL ((struct xenbus_transaction) { 0 })
138
139char **xenbus_directory(struct xenbus_transaction t,
140 const char *dir, const char *node, unsigned int *num);
141void *xenbus_read(struct xenbus_transaction t,
142 const char *dir, const char *node, unsigned int *len);
143int xenbus_write(struct xenbus_transaction t,
144 const char *dir, const char *node, const char *string);
145int xenbus_mkdir(struct xenbus_transaction t,
146 const char *dir, const char *node);
147int xenbus_exists(struct xenbus_transaction t,
148 const char *dir, const char *node);
149int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
150int xenbus_transaction_start(struct xenbus_transaction *t);
151int xenbus_transaction_end(struct xenbus_transaction t, int abort);
152
153/* Single read and scanf: returns -errno or num scanned if > 0. */
154int xenbus_scanf(struct xenbus_transaction t,
155 const char *dir, const char *node, const char *fmt, ...)
156 __attribute__((format(scanf, 4, 5)));
157
158/* Single printf and write: returns -errno or 0. */
159int xenbus_printf(struct xenbus_transaction t,
160 const char *dir, const char *node, const char *fmt, ...)
161 __attribute__((format(printf, 4, 5)));
162
163/* Generic read function: NULL-terminated triples of name,
164 * sprintf-style type string, and pointer. Returns 0 or errno.*/
165int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
166
167/* notifer routines for when the xenstore comes up */
168extern int xenstored_ready;
169int register_xenstore_notifier(struct notifier_block *nb);
170void unregister_xenstore_notifier(struct notifier_block *nb);
171
172int register_xenbus_watch(struct xenbus_watch *watch);
173void unregister_xenbus_watch(struct xenbus_watch *watch);
174void xs_suspend(void);
175void xs_resume(void);
176void xs_suspend_cancel(void);
177
178/* Used by xenbus_dev to borrow kernel's store connection. */
179void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg);
180
181struct work_struct;
182
183/* Prepare for domain suspend: then resume or cancel the suspend. */
184void xenbus_suspend(void);
185void xenbus_resume(void);
186void xenbus_probe(struct work_struct *);
187void xenbus_suspend_cancel(void);
188
189#define XENBUS_IS_ERR_READ(str) ({ \
190 if (!IS_ERR(str) && strlen(str) == 0) { \
191 kfree(str); \
192 str = ERR_PTR(-ERANGE); \
193 } \
194 IS_ERR(str); \
195})
196
197#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
198
199int xenbus_watch_path(struct xenbus_device *dev, const char *path,
200 struct xenbus_watch *watch,
201 void (*callback)(struct xenbus_watch *,
202 const char **, unsigned int));
203int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
204 void (*callback)(struct xenbus_watch *,
205 const char **, unsigned int),
206 const char *pathfmt, ...)
207 __attribute__ ((format (printf, 4, 5)));
208
209int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
210int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
211int xenbus_map_ring_valloc(struct xenbus_device *dev,
212 int gnt_ref, void **vaddr);
213int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
214 grant_handle_t *handle, void *vaddr);
215
216int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
217int xenbus_unmap_ring(struct xenbus_device *dev,
218 grant_handle_t handle, void *vaddr);
219
220int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
221int xenbus_bind_evtchn(struct xenbus_device *dev, int remote_port, int *port);
222int xenbus_free_evtchn(struct xenbus_device *dev, int port);
223
224enum xenbus_state xenbus_read_driver_state(const char *path);
225
226__attribute__((format(printf, 3, 4)))
227void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
228__attribute__((format(printf, 3, 4)))
229void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
230
231const char *xenbus_strstate(enum xenbus_state state);
232int xenbus_dev_is_online(struct xenbus_device *dev);
233int xenbus_frontend_closed(struct xenbus_device *dev);
234
235#endif /* _XEN_XENBUS_H */
1/******************************************************************************
2 * xenbus.h
3 *
4 * Talks to Xen Store to figure out what devices we have.
5 *
6 * Copyright (C) 2005 Rusty Russell, IBM Corporation
7 * Copyright (C) 2005 XenSource Ltd.
8 *
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:
14 *
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:
21 *
22 * The above copyright notice and this permission notice shall be included in
23 * all copies or substantial portions of the Software.
24 *
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
31 * IN THE SOFTWARE.
32 */
33
34#ifndef _XEN_XENBUS_H
35#define _XEN_XENBUS_H
36
37#include <linux/device.h>
38#include <linux/notifier.h>
39#include <linux/mutex.h>
40#include <linux/export.h>
41#include <linux/fs.h>
42#include <linux/completion.h>
43#include <linux/init.h>
44#include <linux/slab.h>
45#include <linux/semaphore.h>
46#include <xen/interface/xen.h>
47#include <xen/interface/grant_table.h>
48#include <xen/interface/io/xenbus.h>
49#include <xen/interface/io/xs_wire.h>
50#include <xen/interface/event_channel.h>
51
52#define XENBUS_MAX_RING_GRANT_ORDER 4
53#define XENBUS_MAX_RING_GRANTS (1U << XENBUS_MAX_RING_GRANT_ORDER)
54
55/* Register callback to watch this node. */
56struct xenbus_watch
57{
58 struct list_head list;
59
60 /* Path being watched. */
61 const char *node;
62
63 unsigned int nr_pending;
64
65 /*
66 * Called just before enqueing new event while a spinlock is held.
67 * The event will be discarded if this callback returns false.
68 */
69 bool (*will_handle)(struct xenbus_watch *,
70 const char *path, const char *token);
71
72 /* Callback (executed in a process context with no locks held). */
73 void (*callback)(struct xenbus_watch *,
74 const char *path, const char *token);
75};
76
77
78/* A xenbus device. */
79struct xenbus_device {
80 const char *devicetype;
81 const char *nodename;
82 const char *otherend;
83 int otherend_id;
84 struct xenbus_watch otherend_watch;
85 struct device dev;
86 enum xenbus_state state;
87 struct completion down;
88 struct work_struct work;
89 struct semaphore reclaim_sem;
90
91 /* Event channel based statistics and settings. */
92 atomic_t event_channels;
93 atomic_t events;
94 atomic_t spurious_events;
95 atomic_t jiffies_eoi_delayed;
96 unsigned int spurious_threshold;
97};
98
99#define to_xenbus_device(__dev) container_of_const(__dev, struct xenbus_device, dev)
100
101struct xenbus_device_id
102{
103 /* .../device/<device_type>/<identifier> */
104 char devicetype[32]; /* General class of device. */
105};
106
107/* A xenbus driver. */
108struct xenbus_driver {
109 const char *name; /* defaults to ids[0].devicetype */
110 const struct xenbus_device_id *ids;
111 bool allow_rebind; /* avoid setting xenstore closed during remove */
112 bool not_essential; /* is not mandatory for boot progress */
113 int (*probe)(struct xenbus_device *dev,
114 const struct xenbus_device_id *id);
115 void (*otherend_changed)(struct xenbus_device *dev,
116 enum xenbus_state backend_state);
117 void (*remove)(struct xenbus_device *dev);
118 int (*suspend)(struct xenbus_device *dev);
119 int (*resume)(struct xenbus_device *dev);
120 int (*uevent)(const struct xenbus_device *, struct kobj_uevent_env *);
121 struct device_driver driver;
122 int (*read_otherend_details)(struct xenbus_device *dev);
123 int (*is_ready)(struct xenbus_device *dev);
124 void (*reclaim_memory)(struct xenbus_device *dev);
125};
126
127#define to_xenbus_driver(__drv) container_of_const(__drv, struct xenbus_driver, driver)
128
129int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
130 struct module *owner,
131 const char *mod_name);
132int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
133 struct module *owner,
134 const char *mod_name);
135
136#define xenbus_register_frontend(drv) \
137 __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME)
138#define xenbus_register_backend(drv) \
139 __xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME)
140
141void xenbus_unregister_driver(struct xenbus_driver *drv);
142
143struct xenbus_transaction
144{
145 u32 id;
146};
147
148/* Nil transaction ID. */
149#define XBT_NIL ((struct xenbus_transaction) { 0 })
150
151char **xenbus_directory(struct xenbus_transaction t,
152 const char *dir, const char *node, unsigned int *num);
153void *xenbus_read(struct xenbus_transaction t,
154 const char *dir, const char *node, unsigned int *len);
155int xenbus_write(struct xenbus_transaction t,
156 const char *dir, const char *node, const char *string);
157int xenbus_mkdir(struct xenbus_transaction t,
158 const char *dir, const char *node);
159int xenbus_exists(struct xenbus_transaction t,
160 const char *dir, const char *node);
161int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
162int xenbus_transaction_start(struct xenbus_transaction *t);
163int xenbus_transaction_end(struct xenbus_transaction t, int abort);
164
165/* Single read and scanf: returns -errno or num scanned if > 0. */
166__scanf(4, 5)
167int xenbus_scanf(struct xenbus_transaction t,
168 const char *dir, const char *node, const char *fmt, ...);
169
170/* Read an (optional) unsigned value. */
171unsigned int xenbus_read_unsigned(const char *dir, const char *node,
172 unsigned int default_val);
173
174/* Single printf and write: returns -errno or 0. */
175__printf(4, 5)
176int xenbus_printf(struct xenbus_transaction t,
177 const char *dir, const char *node, const char *fmt, ...);
178
179/* Generic read function: NULL-terminated triples of name,
180 * sprintf-style type string, and pointer. Returns 0 or errno.*/
181int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
182
183/* notifer routines for when the xenstore comes up */
184extern int xenstored_ready;
185int register_xenstore_notifier(struct notifier_block *nb);
186void unregister_xenstore_notifier(struct notifier_block *nb);
187
188int register_xenbus_watch(struct xenbus_watch *watch);
189void unregister_xenbus_watch(struct xenbus_watch *watch);
190void xs_suspend(void);
191void xs_resume(void);
192void xs_suspend_cancel(void);
193
194struct work_struct;
195
196#define XENBUS_IS_ERR_READ(str) ({ \
197 if (!IS_ERR(str) && strlen(str) == 0) { \
198 kfree(str); \
199 str = ERR_PTR(-ERANGE); \
200 } \
201 IS_ERR(str); \
202})
203
204#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
205
206int xenbus_watch_path(struct xenbus_device *dev, const char *path,
207 struct xenbus_watch *watch,
208 bool (*will_handle)(struct xenbus_watch *,
209 const char *, const char *),
210 void (*callback)(struct xenbus_watch *,
211 const char *, const char *));
212__printf(5, 6)
213int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
214 bool (*will_handle)(struct xenbus_watch *,
215 const char *, const char *),
216 void (*callback)(struct xenbus_watch *,
217 const char *, const char *),
218 const char *pathfmt, ...);
219
220int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
221int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr,
222 unsigned int nr_pages, grant_ref_t *grefs);
223void xenbus_teardown_ring(void **vaddr, unsigned int nr_pages,
224 grant_ref_t *grefs);
225int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
226 unsigned int nr_grefs, void **vaddr);
227
228int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
229
230int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port);
231int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t port);
232
233enum xenbus_state xenbus_read_driver_state(const char *path);
234
235__printf(3, 4)
236void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
237__printf(3, 4)
238void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
239
240const char *xenbus_strstate(enum xenbus_state state);
241int xenbus_dev_is_online(struct xenbus_device *dev);
242int xenbus_frontend_closed(struct xenbus_device *dev);
243
244extern const struct file_operations xen_xenbus_fops;
245extern struct xenstore_domain_interface *xen_store_interface;
246extern int xen_store_evtchn;
247
248#endif /* _XEN_XENBUS_H */