tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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/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>
48
49/* Register callback to watch this node. */
50struct xenbus_watch
51{
52 struct list_head list;
53
54 /* Path being watched. */
55 const char *node;
56
57 /* Callback (executed in a process context with no locks held). */
58 void (*callback)(struct xenbus_watch *,
59 const char **vec, unsigned int len);
60};
61
62
63/* A xenbus device. */
64struct xenbus_device {
65 const char *devicetype;
66 const char *nodename;
67 const char *otherend;
68 int otherend_id;
69 struct xenbus_watch otherend_watch;
70 struct device dev;
71 enum xenbus_state state;
72 struct completion down;
73};
74
75static inline struct xenbus_device *to_xenbus_device(struct device *dev)
76{
77 return container_of(dev, struct xenbus_device, dev);
78}
79
80struct xenbus_device_id
81{
82 /* .../device/<device_type>/<identifier> */
83 char devicetype[32]; /* General class of device. */
84};
85
86/* A xenbus driver. */
87struct xenbus_driver {
88 const struct xenbus_device_id *ids;
89 int (*probe)(struct xenbus_device *dev,
90 const struct xenbus_device_id *id);
91 void (*otherend_changed)(struct xenbus_device *dev,
92 enum xenbus_state backend_state);
93 int (*remove)(struct xenbus_device *dev);
94 int (*suspend)(struct xenbus_device *dev);
95 int (*resume)(struct xenbus_device *dev);
96 int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
97 struct device_driver driver;
98 int (*read_otherend_details)(struct xenbus_device *dev);
99 int (*is_ready)(struct xenbus_device *dev);
100};
101
102#define DEFINE_XENBUS_DRIVER(var, drvname, methods...) \
103struct xenbus_driver var ## _driver = { \
104 .driver.name = drvname + 0 ?: var ## _ids->devicetype, \
105 .driver.owner = THIS_MODULE, \
106 .ids = var ## _ids, ## methods \
107}
108
109static inline struct xenbus_driver *to_xenbus_driver(struct device_driver *drv)
110{
111 return container_of(drv, struct xenbus_driver, driver);
112}
113
114int __must_check xenbus_register_frontend(struct xenbus_driver *);
115int __must_check xenbus_register_backend(struct xenbus_driver *);
116
117void xenbus_unregister_driver(struct xenbus_driver *drv);
118
119struct xenbus_transaction
120{
121 u32 id;
122};
123
124/* Nil transaction ID. */
125#define XBT_NIL ((struct xenbus_transaction) { 0 })
126
127char **xenbus_directory(struct xenbus_transaction t,
128 const char *dir, const char *node, unsigned int *num);
129void *xenbus_read(struct xenbus_transaction t,
130 const char *dir, const char *node, unsigned int *len);
131int xenbus_write(struct xenbus_transaction t,
132 const char *dir, const char *node, const char *string);
133int xenbus_mkdir(struct xenbus_transaction t,
134 const char *dir, const char *node);
135int xenbus_exists(struct xenbus_transaction t,
136 const char *dir, const char *node);
137int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
138int xenbus_transaction_start(struct xenbus_transaction *t);
139int xenbus_transaction_end(struct xenbus_transaction t, int abort);
140
141/* Single read and scanf: returns -errno or num scanned if > 0. */
142__scanf(4, 5)
143int xenbus_scanf(struct xenbus_transaction t,
144 const char *dir, const char *node, const char *fmt, ...);
145
146/* Single printf and write: returns -errno or 0. */
147__printf(4, 5)
148int xenbus_printf(struct xenbus_transaction t,
149 const char *dir, const char *node, const char *fmt, ...);
150
151/* Generic read function: NULL-terminated triples of name,
152 * sprintf-style type string, and pointer. Returns 0 or errno.*/
153int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
154
155/* notifer routines for when the xenstore comes up */
156extern int xenstored_ready;
157int register_xenstore_notifier(struct notifier_block *nb);
158void unregister_xenstore_notifier(struct notifier_block *nb);
159
160int register_xenbus_watch(struct xenbus_watch *watch);
161void unregister_xenbus_watch(struct xenbus_watch *watch);
162void xs_suspend(void);
163void xs_resume(void);
164void xs_suspend_cancel(void);
165
166/* Used by xenbus_dev to borrow kernel's store connection. */
167void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg);
168
169struct work_struct;
170
171/* Prepare for domain suspend: then resume or cancel the suspend. */
172void xenbus_suspend(void);
173void xenbus_resume(void);
174void xenbus_probe(struct work_struct *);
175void xenbus_suspend_cancel(void);
176
177#define XENBUS_IS_ERR_READ(str) ({ \
178 if (!IS_ERR(str) && strlen(str) == 0) { \
179 kfree(str); \
180 str = ERR_PTR(-ERANGE); \
181 } \
182 IS_ERR(str); \
183})
184
185#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
186
187int xenbus_watch_path(struct xenbus_device *dev, const char *path,
188 struct xenbus_watch *watch,
189 void (*callback)(struct xenbus_watch *,
190 const char **, unsigned int));
191__printf(4, 5)
192int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
193 void (*callback)(struct xenbus_watch *,
194 const char **, unsigned int),
195 const char *pathfmt, ...);
196
197int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
198int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
199int xenbus_map_ring_valloc(struct xenbus_device *dev,
200 int gnt_ref, void **vaddr);
201int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
202 grant_handle_t *handle, void *vaddr);
203
204int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
205int xenbus_unmap_ring(struct xenbus_device *dev,
206 grant_handle_t handle, void *vaddr);
207
208int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
209int xenbus_bind_evtchn(struct xenbus_device *dev, int remote_port, int *port);
210int xenbus_free_evtchn(struct xenbus_device *dev, int port);
211
212enum xenbus_state xenbus_read_driver_state(const char *path);
213
214__printf(3, 4)
215void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
216__printf(3, 4)
217void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
218
219const char *xenbus_strstate(enum xenbus_state state);
220int xenbus_dev_is_online(struct xenbus_device *dev);
221int xenbus_frontend_closed(struct xenbus_device *dev);
222
223#endif /* _XEN_XENBUS_H */