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v5.4
  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 <xen/interface/xen.h>
 46#include <xen/interface/grant_table.h>
 47#include <xen/interface/io/xenbus.h>
 48#include <xen/interface/io/xs_wire.h>
 
 49
 50#define XENBUS_MAX_RING_GRANT_ORDER 4
 51#define XENBUS_MAX_RING_GRANTS      (1U << XENBUS_MAX_RING_GRANT_ORDER)
 52#define INVALID_GRANT_HANDLE       (~0U)
 53
 54/* Register callback to watch this node. */
 55struct xenbus_watch
 56{
 57	struct list_head list;
 58
 59	/* Path being watched. */
 60	const char *node;
 61
 62	/* Callback (executed in a process context with no locks held). */
 63	void (*callback)(struct xenbus_watch *,
 64			 const char *path, const char *token);
 65};
 66
 67
 68/* A xenbus device. */
 69struct xenbus_device {
 70	const char *devicetype;
 71	const char *nodename;
 72	const char *otherend;
 73	int otherend_id;
 74	struct xenbus_watch otherend_watch;
 75	struct device dev;
 76	enum xenbus_state state;
 77	struct completion down;
 78	struct work_struct work;
 
 79};
 80
 81static inline struct xenbus_device *to_xenbus_device(struct device *dev)
 82{
 83	return container_of(dev, struct xenbus_device, dev);
 84}
 85
 86struct xenbus_device_id
 87{
 88	/* .../device/<device_type>/<identifier> */
 89	char devicetype[32]; 	/* General class of device. */
 90};
 91
 92/* A xenbus driver. */
 93struct xenbus_driver {
 94	const char *name;       /* defaults to ids[0].devicetype */
 95	const struct xenbus_device_id *ids;
 
 96	int (*probe)(struct xenbus_device *dev,
 97		     const struct xenbus_device_id *id);
 98	void (*otherend_changed)(struct xenbus_device *dev,
 99				 enum xenbus_state backend_state);
100	int (*remove)(struct xenbus_device *dev);
101	int (*suspend)(struct xenbus_device *dev);
102	int (*resume)(struct xenbus_device *dev);
103	int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
104	struct device_driver driver;
105	int (*read_otherend_details)(struct xenbus_device *dev);
106	int (*is_ready)(struct xenbus_device *dev);
 
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 *drv,
115					    struct module *owner,
116					    const char *mod_name);
117int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
118					   struct module *owner,
119					   const char *mod_name);
120
121#define xenbus_register_frontend(drv) \
122	__xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME)
123#define xenbus_register_backend(drv) \
124	__xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME)
125
126void xenbus_unregister_driver(struct xenbus_driver *drv);
127
128struct xenbus_transaction
129{
130	u32 id;
131};
132
133/* Nil transaction ID. */
134#define XBT_NIL ((struct xenbus_transaction) { 0 })
135
136char **xenbus_directory(struct xenbus_transaction t,
137			const char *dir, const char *node, unsigned int *num);
138void *xenbus_read(struct xenbus_transaction t,
139		  const char *dir, const char *node, unsigned int *len);
140int xenbus_write(struct xenbus_transaction t,
141		 const char *dir, const char *node, const char *string);
142int xenbus_mkdir(struct xenbus_transaction t,
143		 const char *dir, const char *node);
144int xenbus_exists(struct xenbus_transaction t,
145		  const char *dir, const char *node);
146int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
147int xenbus_transaction_start(struct xenbus_transaction *t);
148int xenbus_transaction_end(struct xenbus_transaction t, int abort);
149
150/* Single read and scanf: returns -errno or num scanned if > 0. */
151__scanf(4, 5)
152int xenbus_scanf(struct xenbus_transaction t,
153		 const char *dir, const char *node, const char *fmt, ...);
154
155/* Read an (optional) unsigned value. */
156unsigned int xenbus_read_unsigned(const char *dir, const char *node,
157				  unsigned int default_val);
158
159/* Single printf and write: returns -errno or 0. */
160__printf(4, 5)
161int xenbus_printf(struct xenbus_transaction t,
162		  const char *dir, const char *node, const char *fmt, ...);
163
164/* Generic read function: NULL-terminated triples of name,
165 * sprintf-style type string, and pointer. Returns 0 or errno.*/
166int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
167
168/* notifer routines for when the xenstore comes up */
169extern int xenstored_ready;
170int register_xenstore_notifier(struct notifier_block *nb);
171void unregister_xenstore_notifier(struct notifier_block *nb);
172
173int register_xenbus_watch(struct xenbus_watch *watch);
174void unregister_xenbus_watch(struct xenbus_watch *watch);
175void xs_suspend(void);
176void xs_resume(void);
177void xs_suspend_cancel(void);
178
179struct work_struct;
180
181void xenbus_probe(struct work_struct *);
182
183#define XENBUS_IS_ERR_READ(str) ({			\
184	if (!IS_ERR(str) && strlen(str) == 0) {		\
185		kfree(str);				\
186		str = ERR_PTR(-ERANGE);			\
187	}						\
188	IS_ERR(str);					\
189})
190
191#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
192
193int xenbus_watch_path(struct xenbus_device *dev, const char *path,
194		      struct xenbus_watch *watch,
195		      void (*callback)(struct xenbus_watch *,
196				       const char *, const char *));
197__printf(4, 5)
198int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
199			 void (*callback)(struct xenbus_watch *,
200					  const char *, const char *),
201			 const char *pathfmt, ...);
202
203int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
204int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
205		      unsigned int nr_pages, grant_ref_t *grefs);
206int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
207			   unsigned int nr_grefs, void **vaddr);
208int xenbus_map_ring(struct xenbus_device *dev,
209		    grant_ref_t *gnt_refs, unsigned int nr_grefs,
210		    grant_handle_t *handles, unsigned long *vaddrs,
211		    bool *leaked);
212
213int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
214int xenbus_unmap_ring(struct xenbus_device *dev,
215		      grant_handle_t *handles, unsigned int nr_handles,
216		      unsigned long *vaddrs);
217
218int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
219int xenbus_free_evtchn(struct xenbus_device *dev, int port);
220
221enum xenbus_state xenbus_read_driver_state(const char *path);
222
223__printf(3, 4)
224void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
225__printf(3, 4)
226void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
227
228const char *xenbus_strstate(enum xenbus_state state);
229int xenbus_dev_is_online(struct xenbus_device *dev);
230int xenbus_frontend_closed(struct xenbus_device *dev);
231
232extern const struct file_operations xen_xenbus_fops;
233extern struct xenstore_domain_interface *xen_store_interface;
234extern int xen_store_evtchn;
235
236#endif /* _XEN_XENBUS_H */
v5.9
  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#define INVALID_GRANT_HANDLE       (~0U)
 55
 56/* Register callback to watch this node. */
 57struct xenbus_watch
 58{
 59	struct list_head list;
 60
 61	/* Path being watched. */
 62	const char *node;
 63
 64	/* Callback (executed in a process context with no locks held). */
 65	void (*callback)(struct xenbus_watch *,
 66			 const char *path, const char *token);
 67};
 68
 69
 70/* A xenbus device. */
 71struct xenbus_device {
 72	const char *devicetype;
 73	const char *nodename;
 74	const char *otherend;
 75	int otherend_id;
 76	struct xenbus_watch otherend_watch;
 77	struct device dev;
 78	enum xenbus_state state;
 79	struct completion down;
 80	struct work_struct work;
 81	struct semaphore reclaim_sem;
 82};
 83
 84static inline struct xenbus_device *to_xenbus_device(struct device *dev)
 85{
 86	return container_of(dev, struct xenbus_device, dev);
 87}
 88
 89struct xenbus_device_id
 90{
 91	/* .../device/<device_type>/<identifier> */
 92	char devicetype[32]; 	/* General class of device. */
 93};
 94
 95/* A xenbus driver. */
 96struct xenbus_driver {
 97	const char *name;       /* defaults to ids[0].devicetype */
 98	const struct xenbus_device_id *ids;
 99	bool allow_rebind; /* avoid setting xenstore closed during remove */
100	int (*probe)(struct xenbus_device *dev,
101		     const struct xenbus_device_id *id);
102	void (*otherend_changed)(struct xenbus_device *dev,
103				 enum xenbus_state backend_state);
104	int (*remove)(struct xenbus_device *dev);
105	int (*suspend)(struct xenbus_device *dev);
106	int (*resume)(struct xenbus_device *dev);
107	int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
108	struct device_driver driver;
109	int (*read_otherend_details)(struct xenbus_device *dev);
110	int (*is_ready)(struct xenbus_device *dev);
111	void (*reclaim_memory)(struct xenbus_device *dev);
112};
113
114static inline struct xenbus_driver *to_xenbus_driver(struct device_driver *drv)
115{
116	return container_of(drv, struct xenbus_driver, driver);
117}
118
119int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
120					    struct module *owner,
121					    const char *mod_name);
122int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
123					   struct module *owner,
124					   const char *mod_name);
125
126#define xenbus_register_frontend(drv) \
127	__xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME)
128#define xenbus_register_backend(drv) \
129	__xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME)
130
131void xenbus_unregister_driver(struct xenbus_driver *drv);
132
133struct xenbus_transaction
134{
135	u32 id;
136};
137
138/* Nil transaction ID. */
139#define XBT_NIL ((struct xenbus_transaction) { 0 })
140
141char **xenbus_directory(struct xenbus_transaction t,
142			const char *dir, const char *node, unsigned int *num);
143void *xenbus_read(struct xenbus_transaction t,
144		  const char *dir, const char *node, unsigned int *len);
145int xenbus_write(struct xenbus_transaction t,
146		 const char *dir, const char *node, const char *string);
147int xenbus_mkdir(struct xenbus_transaction t,
148		 const char *dir, const char *node);
149int xenbus_exists(struct xenbus_transaction t,
150		  const char *dir, const char *node);
151int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
152int xenbus_transaction_start(struct xenbus_transaction *t);
153int xenbus_transaction_end(struct xenbus_transaction t, int abort);
154
155/* Single read and scanf: returns -errno or num scanned if > 0. */
156__scanf(4, 5)
157int xenbus_scanf(struct xenbus_transaction t,
158		 const char *dir, const char *node, const char *fmt, ...);
159
160/* Read an (optional) unsigned value. */
161unsigned int xenbus_read_unsigned(const char *dir, const char *node,
162				  unsigned int default_val);
163
164/* Single printf and write: returns -errno or 0. */
165__printf(4, 5)
166int xenbus_printf(struct xenbus_transaction t,
167		  const char *dir, const char *node, const char *fmt, ...);
168
169/* Generic read function: NULL-terminated triples of name,
170 * sprintf-style type string, and pointer. Returns 0 or errno.*/
171int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
172
173/* notifer routines for when the xenstore comes up */
174extern int xenstored_ready;
175int register_xenstore_notifier(struct notifier_block *nb);
176void unregister_xenstore_notifier(struct notifier_block *nb);
177
178int register_xenbus_watch(struct xenbus_watch *watch);
179void unregister_xenbus_watch(struct xenbus_watch *watch);
180void xs_suspend(void);
181void xs_resume(void);
182void xs_suspend_cancel(void);
183
184struct work_struct;
185
186void xenbus_probe(struct work_struct *);
187
188#define XENBUS_IS_ERR_READ(str) ({			\
189	if (!IS_ERR(str) && strlen(str) == 0) {		\
190		kfree(str);				\
191		str = ERR_PTR(-ERANGE);			\
192	}						\
193	IS_ERR(str);					\
194})
195
196#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)
197
198int xenbus_watch_path(struct xenbus_device *dev, const char *path,
199		      struct xenbus_watch *watch,
200		      void (*callback)(struct xenbus_watch *,
201				       const char *, const char *));
202__printf(4, 5)
203int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
204			 void (*callback)(struct xenbus_watch *,
205					  const char *, const char *),
206			 const char *pathfmt, ...);
207
208int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
209int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
210		      unsigned int nr_pages, grant_ref_t *grefs);
211int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
212			   unsigned int nr_grefs, void **vaddr);
 
 
 
 
213
214int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
 
 
 
215
216int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port);
217int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t port);
218
219enum xenbus_state xenbus_read_driver_state(const char *path);
220
221__printf(3, 4)
222void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
223__printf(3, 4)
224void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);
225
226const char *xenbus_strstate(enum xenbus_state state);
227int xenbus_dev_is_online(struct xenbus_device *dev);
228int xenbus_frontend_closed(struct xenbus_device *dev);
229
230extern const struct file_operations xen_xenbus_fops;
231extern struct xenstore_domain_interface *xen_store_interface;
232extern int xen_store_evtchn;
233
234#endif /* _XEN_XENBUS_H */