[mirror_ubuntu-artful-kernel.git] / include / xen / xenbus.h

/******************************************************************************
 * xenbus.h
 *
 * Talks to Xen Store to figure out what devices we have.
 *
 * Copyright (C) 2005 Rusty Russell, IBM Corporation
 * Copyright (C) 2005 XenSource Ltd.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation; or, when distributed
 * separately from the Linux kernel or incorporated into other
 * software packages, subject to the following license:
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this source file (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#ifndef _XEN_XENBUS_H
#define _XEN_XENBUS_H

#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/mutex.h>
#include <linux/completion.h>
#include <linux/init.h>
#include <xen/interface/xen.h>
#include <xen/interface/grant_table.h>
#include <xen/interface/io/xenbus.h>
#include <xen/interface/io/xs_wire.h>

/* Register callback to watch this node. */
struct xenbus_watch
{
	struct list_head list;

	/* Path being watched. */
	const char *node;

	/* Callback (executed in a process context with no locks held). */
	void (*callback)(struct xenbus_watch *,
			 const char **vec, unsigned int len);
};


/* A xenbus device. */
struct xenbus_device {
	const char *devicetype;
	const char *nodename;
	const char *otherend;
	int otherend_id;
	struct xenbus_watch otherend_watch;
	struct device dev;
	enum xenbus_state state;
	struct completion down;
};

static inline struct xenbus_device *to_xenbus_device(struct device *dev)
{
	return container_of(dev, struct xenbus_device, dev);
}

struct xenbus_device_id
{
	/* .../device/<device_type>/<identifier> */
	char devicetype[32]; 	/* General class of device. */
};

/* A xenbus driver. */
struct xenbus_driver {
	char *name;
	struct module *owner;
	const struct xenbus_device_id *ids;
	int (*probe)(struct xenbus_device *dev,
		     const struct xenbus_device_id *id);
	void (*otherend_changed)(struct xenbus_device *dev,
				 enum xenbus_state backend_state);
	int (*remove)(struct xenbus_device *dev);
	int (*suspend)(struct xenbus_device *dev, pm_message_t state);
	int (*resume)(struct xenbus_device *dev);
	int (*uevent)(struct xenbus_device *, char **, int, char *, int);
	struct device_driver driver;
	int (*read_otherend_details)(struct xenbus_device *dev);
	int (*is_ready)(struct xenbus_device *dev);
};

static inline struct xenbus_driver *to_xenbus_driver(struct device_driver *drv)
{
	return container_of(drv, struct xenbus_driver, driver);
}

int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
					    struct module *owner,
					    const char *mod_name);

static inline int __must_check
xenbus_register_frontend(struct xenbus_driver *drv)
{
	WARN_ON(drv->owner != THIS_MODULE);
	return __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME);
}

int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
					   struct module *owner,
					   const char *mod_name);
static inline int __must_check
xenbus_register_backend(struct xenbus_driver *drv)
{
	WARN_ON(drv->owner != THIS_MODULE);
	return __xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME);
}

void xenbus_unregister_driver(struct xenbus_driver *drv);

struct xenbus_transaction
{
	u32 id;
};

/* Nil transaction ID. */
#define XBT_NIL ((struct xenbus_transaction) { 0 })

char **xenbus_directory(struct xenbus_transaction t,
			const char *dir, const char *node, unsigned int *num);
void *xenbus_read(struct xenbus_transaction t,
		  const char *dir, const char *node, unsigned int *len);
int xenbus_write(struct xenbus_transaction t,
		 const char *dir, const char *node, const char *string);
int xenbus_mkdir(struct xenbus_transaction t,
		 const char *dir, const char *node);
int xenbus_exists(struct xenbus_transaction t,
		  const char *dir, const char *node);
int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
int xenbus_transaction_start(struct xenbus_transaction *t);
int xenbus_transaction_end(struct xenbus_transaction t, int abort);

/* Single read and scanf: returns -errno or num scanned if > 0. */
int xenbus_scanf(struct xenbus_transaction t,
		 const char *dir, const char *node, const char *fmt, ...)
	__attribute__((format(scanf, 4, 5)));

/* Single printf and write: returns -errno or 0. */
int xenbus_printf(struct xenbus_transaction t,
		  const char *dir, const char *node, const char *fmt, ...)
	__attribute__((format(printf, 4, 5)));

/* Generic read function: NULL-terminated triples of name,
 * sprintf-style type string, and pointer. Returns 0 or errno.*/
int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);

/* notifer routines for when the xenstore comes up */
extern int xenstored_ready;
int register_xenstore_notifier(struct notifier_block *nb);
void unregister_xenstore_notifier(struct notifier_block *nb);

int register_xenbus_watch(struct xenbus_watch *watch);
void unregister_xenbus_watch(struct xenbus_watch *watch);
void xs_suspend(void);
void xs_resume(void);
void xs_suspend_cancel(void);

/* Used by xenbus_dev to borrow kernel's store connection. */
void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg);

struct work_struct;

/* Prepare for domain suspend: then resume or cancel the suspend. */
void xenbus_suspend(void);
void xenbus_resume(void);
void xenbus_probe(struct work_struct *);
void xenbus_suspend_cancel(void);

#define XENBUS_IS_ERR_READ(str) ({			\
	if (!IS_ERR(str) && strlen(str) == 0) {		\
		kfree(str);				\
		str = ERR_PTR(-ERANGE);			\
	}						\
	IS_ERR(str);					\
})

#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE)

int xenbus_watch_path(struct xenbus_device *dev, const char *path,
		      struct xenbus_watch *watch,
		      void (*callback)(struct xenbus_watch *,
				       const char **, unsigned int));
int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
			 void (*callback)(struct xenbus_watch *,
					  const char **, unsigned int),
			 const char *pathfmt, ...)
	__attribute__ ((format (printf, 4, 5)));

int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
int xenbus_map_ring_valloc(struct xenbus_device *dev,
			   int gnt_ref, void **vaddr);
int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
			   grant_handle_t *handle, void *vaddr);

int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
int xenbus_unmap_ring(struct xenbus_device *dev,
		      grant_handle_t handle, void *vaddr);

int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
int xenbus_bind_evtchn(struct xenbus_device *dev, int remote_port, int *port);
int xenbus_free_evtchn(struct xenbus_device *dev, int port);

enum xenbus_state xenbus_read_driver_state(const char *path);

void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...);

const char *xenbus_strstate(enum xenbus_state state);
int xenbus_dev_is_online(struct xenbus_device *dev);
int xenbus_frontend_closed(struct xenbus_device *dev);

#endif /* _XEN_XENBUS_H */
Commit	Line	Data
4bac07c9 JF	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 <xen/interface/xen.h>
	43	#include <xen/interface/grant_table.h>
	44	#include <xen/interface/io/xenbus.h>
	45	#include <xen/interface/io/xs_wire.h>
	46
	47	/* Register callback to watch this node. */
	48	struct xenbus_watch
	49	{
	50	struct list_head list;
	51
	52	/* Path being watched. */
	53	const char *node;
	54
	55	/* Callback (executed in a process context with no locks held). */
	56	void (callback)(struct xenbus_watch ,
	57	const char **vec, unsigned int len);
	58	};
	59
	60
	61	/* A xenbus device. */
	62	struct xenbus_device {
	63	const char *devicetype;
	64	const char *nodename;
65	const char *otherend;
66	int otherend_id;
67	struct xenbus_watch otherend_watch;
68	struct device dev;
69	enum xenbus_state state;
70	struct completion down;
71	};
72
73	static inline struct xenbus_device to_xenbus_device(struct device dev)
74	{
75	return container_of(dev, struct xenbus_device, dev);
76	}
77
78	struct xenbus_device_id
79	{
80	/* .../device/<device_type>/<identifier> */
81	char devicetype[32]; /* General class of device. */
82	};
83
84	/* A xenbus driver. */
85	struct xenbus_driver {
86	char *name;
87	struct module *owner;
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);
de5b31bd	94	int (suspend)(struct xenbus_device dev, pm_message_t state);
4bac07c9 JF	95	int (resume)(struct xenbus_device dev);
	96	int (uevent)(struct xenbus_device , char *, int, char , int);
	97	struct device_driver driver;
	98	int (read_otherend_details)(struct xenbus_device dev);
1d78d705	99	int (is_ready)(struct xenbus_device dev);
4bac07c9 JF	100	};
	101
	102	static inline struct xenbus_driver to_xenbus_driver(struct device_driver drv)
	103	{
	104	return container_of(drv, struct xenbus_driver, driver);
	105	}
	106
	107	int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
	108	struct module *owner,
	109	const char *mod_name);
	110
	111	static inline int __must_check
	112	xenbus_register_frontend(struct xenbus_driver *drv)
	113	{
	114	WARN_ON(drv->owner != THIS_MODULE);
	115	return __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME);
	116	}
	117
	118	int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
	119	struct module *owner,
	120	const char *mod_name);
	121	static inline int __must_check
	122	xenbus_register_backend(struct xenbus_driver *drv)
	123	{
	124	WARN_ON(drv->owner != THIS_MODULE);
	125	return __xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME);
	126	}
	127
	128	void xenbus_unregister_driver(struct xenbus_driver *drv);
	129
	130	struct xenbus_transaction
	131	{
	132	u32 id;
	133	};
	134
	135	/* Nil transaction ID. */
	136	#define XBT_NIL ((struct xenbus_transaction) { 0 })
	137
4bac07c9 JF	138	char **xenbus_directory(struct xenbus_transaction t,
	139	const char dir, const char node, unsigned int *num);
	140	void *xenbus_read(struct xenbus_transaction t,
	141	const char dir, const char node, unsigned int *len);
	142	int xenbus_write(struct xenbus_transaction t,
	143	const char dir, const char node, const char *string);
	144	int xenbus_mkdir(struct xenbus_transaction t,
	145	const char dir, const char node);
	146	int xenbus_exists(struct xenbus_transaction t,
	147	const char dir, const char node);
	148	int xenbus_rm(struct xenbus_transaction t, const char dir, const char node);
	149	int xenbus_transaction_start(struct xenbus_transaction *t);
	150	int xenbus_transaction_end(struct xenbus_transaction t, int abort);
	151
	152	/* Single read and scanf: returns -errno or num scanned if > 0. */
	153	int xenbus_scanf(struct xenbus_transaction t,
	154	const char dir, const char node, const char *fmt, ...)
	155	__attribute__((format(scanf, 4, 5)));
	156
	157	/* Single printf and write: returns -errno or 0. */
	158	int xenbus_printf(struct xenbus_transaction t,
	159	const char dir, const char node, const char *fmt, ...)
	160	__attribute__((format(printf, 4, 5)));
	161
	162	/* Generic read function: NULL-terminated triples of name,
	163	* sprintf-style type string, and pointer. Returns 0 or errno.*/
	164	int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
	165
	166	/* notifer routines for when the xenstore comes up */
	167	extern int xenstored_ready;
	168	int register_xenstore_notifier(struct notifier_block *nb);
	169	void unregister_xenstore_notifier(struct notifier_block *nb);
	170
	171	int register_xenbus_watch(struct xenbus_watch *watch);
	172	void unregister_xenbus_watch(struct xenbus_watch *watch);
	173	void xs_suspend(void);
	174	void xs_resume(void);
	175	void xs_suspend_cancel(void);
	176
	177	/* Used by xenbus_dev to borrow kernel's store connection. */
	178	void xenbus_dev_request_and_reply(struct xsd_sockmsg msg);
	179
	180	struct work_struct;
	181
	182	/* Prepare for domain suspend: then resume or cancel the suspend. */
	183	void xenbus_suspend(void);
	184	void xenbus_resume(void);
	185	void xenbus_probe(struct work_struct *);
	186	void xenbus_suspend_cancel(void);
	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
	198	int xenbus_watch_path(struct xenbus_device dev, const char path,
	199	struct xenbus_watch *watch,
	200	void (callback)(struct xenbus_watch ,
	201	const char **, unsigned int));
202	int xenbus_watch_pathfmt(struct xenbus_device dev, struct xenbus_watch watch,
203	void (callback)(struct xenbus_watch ,
204	const char **, unsigned int),
205	const char *pathfmt, ...)
206	__attribute__ ((format (printf, 4, 5)));
207
208	int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
209	int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
210	int xenbus_map_ring_valloc(struct xenbus_device *dev,
211	int gnt_ref, void **vaddr);
212	int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
213	grant_handle_t handle, void vaddr);
214
215	int xenbus_unmap_ring_vfree(struct xenbus_device dev, void vaddr);
216	int xenbus_unmap_ring(struct xenbus_device *dev,
217	grant_handle_t handle, void *vaddr);
218
219	int xenbus_alloc_evtchn(struct xenbus_device dev, int port);
220	int xenbus_bind_evtchn(struct xenbus_device dev, int remote_port, int port);
221	int xenbus_free_evtchn(struct xenbus_device *dev, int port);
222
223	enum xenbus_state xenbus_read_driver_state(const char *path);
224
225	void xenbus_dev_error(struct xenbus_device dev, int err, const char fmt, ...);
226	void xenbus_dev_fatal(struct xenbus_device dev, int err, const char fmt, ...);
227
228	const char *xenbus_strstate(enum xenbus_state state);
229	int xenbus_dev_is_online(struct xenbus_device *dev);
230	int xenbus_frontend_closed(struct xenbus_device *dev);
231
232	#endif /* _XEN_XENBUS_H */