[linux-2.6-block.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 <linux/slab.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>
5a0e3ad6	42	#include <linux/slab.h>
4bac07c9 JF	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. */
	49	struct 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. */
	63	struct 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
	74	static inline struct xenbus_device to_xenbus_device(struct device dev)
	75	{
	76	return container_of(dev, struct xenbus_device, dev);
	77	}
	78
	79	struct xenbus_device_id
	80	{
	81	/* .../device/<device_type>/<identifier> */
	82	char devicetype[32]; /* General class of device. */
	83	};
	84
	85	/* A xenbus driver. */
	86	struct 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);
de5b31bd	95	int (suspend)(struct xenbus_device dev, pm_message_t state);
4bac07c9 JF	96	int (resume)(struct xenbus_device dev);
	97	int (uevent)(struct xenbus_device , char *, int, char , int);
	98	struct device_driver driver;
	99	int (read_otherend_details)(struct xenbus_device dev);
1d78d705	100	int (is_ready)(struct xenbus_device dev);
4bac07c9 JF	101	};
	102
	103	static inline struct xenbus_driver to_xenbus_driver(struct device_driver drv)
	104	{
	105	return container_of(drv, struct xenbus_driver, driver);
	106	}
	107
	108	int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
	109	struct module *owner,
	110	const char *mod_name);
	111
	112	static inline int __must_check
	113	xenbus_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
	119	int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
	120	struct module *owner,
	121	const char *mod_name);
	122	static inline int __must_check
	123	xenbus_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
	129	void xenbus_unregister_driver(struct xenbus_driver *drv);
	130
	131	struct xenbus_transaction
	132	{
	133	u32 id;
	134	};
	135
	136	/* Nil transaction ID. */
	137	#define XBT_NIL ((struct xenbus_transaction) { 0 })
	138
4bac07c9 JF	139	char **xenbus_directory(struct xenbus_transaction t,
	140	const char dir, const char node, unsigned int *num);
	141	void *xenbus_read(struct xenbus_transaction t,
	142	const char dir, const char node, unsigned int *len);
	143	int xenbus_write(struct xenbus_transaction t,
	144	const char dir, const char node, const char *string);
	145	int xenbus_mkdir(struct xenbus_transaction t,
	146	const char dir, const char node);
	147	int xenbus_exists(struct xenbus_transaction t,
	148	const char dir, const char node);
	149	int xenbus_rm(struct xenbus_transaction t, const char dir, const char node);
	150	int xenbus_transaction_start(struct xenbus_transaction *t);
	151	int xenbus_transaction_end(struct xenbus_transaction t, int abort);
	152
	153	/* Single read and scanf: returns -errno or num scanned if > 0. */
	154	int 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. */
	159	int 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.*/
	165	int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
	166
	167	/* notifer routines for when the xenstore comes up */
	168	extern int xenstored_ready;
	169	int register_xenstore_notifier(struct notifier_block *nb);
	170	void unregister_xenstore_notifier(struct notifier_block *nb);
	171
	172	int register_xenbus_watch(struct xenbus_watch *watch);
	173	void unregister_xenbus_watch(struct xenbus_watch *watch);
	174	void xs_suspend(void);
	175	void xs_resume(void);
	176	void xs_suspend_cancel(void);
	177
	178	/* Used by xenbus_dev to borrow kernel's store connection. */
	179	void xenbus_dev_request_and_reply(struct xsd_sockmsg msg);
	180
	181	struct work_struct;
	182
	183	/* Prepare for domain suspend: then resume or cancel the suspend. */
	184	void xenbus_suspend(void);
	185	void xenbus_resume(void);
	186	void xenbus_probe(struct work_struct *);
	187	void 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
	199	int 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));
203	int 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
209	int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
210	int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
211	int xenbus_map_ring_valloc(struct xenbus_device *dev,
212	int gnt_ref, void **vaddr);
213	int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
214	grant_handle_t handle, void vaddr);
215
216	int xenbus_unmap_ring_vfree(struct xenbus_device dev, void vaddr);
217	int xenbus_unmap_ring(struct xenbus_device *dev,
218	grant_handle_t handle, void *vaddr);
219
220	int xenbus_alloc_evtchn(struct xenbus_device dev, int port);
221	int xenbus_bind_evtchn(struct xenbus_device dev, int remote_port, int port);
222	int xenbus_free_evtchn(struct xenbus_device *dev, int port);
223
224	enum xenbus_state xenbus_read_driver_state(const char *path);
225
226	void xenbus_dev_error(struct xenbus_device dev, int err, const char fmt, ...);
227	void xenbus_dev_fatal(struct xenbus_device dev, int err, const char fmt, ...);
228
229	const char *xenbus_strstate(enum xenbus_state state);
230	int xenbus_dev_is_online(struct xenbus_device *dev);
231	int xenbus_frontend_closed(struct xenbus_device *dev);
232
233	#endif /* _XEN_XENBUS_H */