[linux.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/export.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);
	int (*resume)(struct xenbus_device *dev);
	int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
	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. */
__printf(4, 5)
int xenbus_printf(struct xenbus_transaction t,
		  const char *dir, const char *node, const char *fmt, ...);

/* 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));
__printf(4, 5)
int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
			 void (*callback)(struct xenbus_watch *,
					  const char **, unsigned int),
			 const char *pathfmt, ...);

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);

__printf(3, 4)
void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
__printf(3, 4)
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>
63c9744b	40	#include <linux/export.h>
4bac07c9 JF	41	#include <linux/completion.h>
4bac07c9 JF	42	#include <linux/init.h>
5a0e3ad6	43	#include <linux/slab.h>
4bac07c9 JF	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. */
	50	struct 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. */
	64	struct 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
	75	static inline struct xenbus_device to_xenbus_device(struct device dev)
	76	{
	77	return container_of(dev, struct xenbus_device, dev);
	78	}
	79
	80	struct xenbus_device_id
	81	{
	82	/* .../device/<device_type>/<identifier> */
	83	char devicetype[32]; /* General class of device. */
	84	};
	85
	86	/* A xenbus driver. */
	87	struct xenbus_driver {
	88	char *name;
	89	struct module *owner;
	90	const struct xenbus_device_id *ids;
	91	int (probe)(struct xenbus_device dev,
	92	const struct xenbus_device_id *id);
	93	void (otherend_changed)(struct xenbus_device dev,
	94	enum xenbus_state backend_state);
	95	int (remove)(struct xenbus_device dev);
c7853aea	96	int (suspend)(struct xenbus_device dev);
4bac07c9	97	int (resume)(struct xenbus_device dev);
df660251	98	int (uevent)(struct xenbus_device , struct kobj_uevent_env *);
4bac07c9 JF	99	struct device_driver driver;
4bac07c9 JF	100	int (read_otherend_details)(struct xenbus_device dev);
1d78d705	101	int (is_ready)(struct xenbus_device dev);
4bac07c9 JF	102	};
	103
	104	static inline struct xenbus_driver to_xenbus_driver(struct device_driver drv)
	105	{
	106	return container_of(drv, struct xenbus_driver, driver);
	107	}
	108
	109	int __must_check __xenbus_register_frontend(struct xenbus_driver *drv,
	110	struct module *owner,
	111	const char *mod_name);
	112
	113	static inline int __must_check
	114	xenbus_register_frontend(struct xenbus_driver *drv)
	115	{
	116	WARN_ON(drv->owner != THIS_MODULE);
	117	return __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME);
	118	}
	119
	120	int __must_check __xenbus_register_backend(struct xenbus_driver *drv,
	121	struct module *owner,
	122	const char *mod_name);
	123	static inline int __must_check
	124	xenbus_register_backend(struct xenbus_driver *drv)
	125	{
	126	WARN_ON(drv->owner != THIS_MODULE);
	127	return __xenbus_register_backend(drv, THIS_MODULE, KBUILD_MODNAME);
	128	}
	129
	130	void xenbus_unregister_driver(struct xenbus_driver *drv);
	131
	132	struct xenbus_transaction
	133	{
	134	u32 id;
	135	};
	136
	137	/* Nil transaction ID. */
	138	#define XBT_NIL ((struct xenbus_transaction) { 0 })
	139
4bac07c9 JF	140	char **xenbus_directory(struct xenbus_transaction t,
	141	const char dir, const char node, unsigned int *num);
	142	void *xenbus_read(struct xenbus_transaction t,
	143	const char dir, const char node, unsigned int *len);
	144	int xenbus_write(struct xenbus_transaction t,
	145	const char dir, const char node, const char *string);
	146	int xenbus_mkdir(struct xenbus_transaction t,
	147	const char dir, const char node);
	148	int xenbus_exists(struct xenbus_transaction t,
	149	const char dir, const char node);
	150	int xenbus_rm(struct xenbus_transaction t, const char dir, const char node);
	151	int xenbus_transaction_start(struct xenbus_transaction *t);
	152	int xenbus_transaction_end(struct xenbus_transaction t, int abort);
	153
	154	/* Single read and scanf: returns -errno or num scanned if > 0. */
	155	int xenbus_scanf(struct xenbus_transaction t,
	156	const char dir, const char node, const char *fmt, ...)
	157	__attribute__((format(scanf, 4, 5)));
	158
	159	/* Single printf and write: returns -errno or 0. */
b9075fa9	160	__printf(4, 5)
4bac07c9	161	int xenbus_printf(struct xenbus_transaction t,
b9075fa9	162	const char dir, const char node, const char *fmt, ...);
4bac07c9 JF	163
	164	/* Generic read function: NULL-terminated triples of name,
	165	* sprintf-style type string, and pointer. Returns 0 or errno.*/
	166	int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
	167
	168	/* notifer routines for when the xenstore comes up */
	169	extern int xenstored_ready;
	170	int register_xenstore_notifier(struct notifier_block *nb);
	171	void unregister_xenstore_notifier(struct notifier_block *nb);
	172
	173	int register_xenbus_watch(struct xenbus_watch *watch);
	174	void unregister_xenbus_watch(struct xenbus_watch *watch);
	175	void xs_suspend(void);
	176	void xs_resume(void);
	177	void xs_suspend_cancel(void);
	178
	179	/* Used by xenbus_dev to borrow kernel's store connection. */
	180	void xenbus_dev_request_and_reply(struct xsd_sockmsg msg);
	181
	182	struct work_struct;
	183
	184	/* Prepare for domain suspend: then resume or cancel the suspend. */
	185	void xenbus_suspend(void);
	186	void xenbus_resume(void);
	187	void xenbus_probe(struct work_struct *);
	188	void xenbus_suspend_cancel(void);
	189
	190	#define XENBUS_IS_ERR_READ(str) ({ \
	191	if (!IS_ERR(str) && strlen(str) == 0) { \
	192	kfree(str); \
	193	str = ERR_PTR(-ERANGE); \
	194	} \
	195	IS_ERR(str); \
	196	})
	197
	198	#define XENBUS_EXIST_ERR(err) ((err) == -ENOENT \|\| (err) == -ERANGE)
	199
	200	int xenbus_watch_path(struct xenbus_device dev, const char path,
	201	struct xenbus_watch *watch,
	202	void (callback)(struct xenbus_watch ,
	203	const char **, unsigned int));
b9075fa9	204	__printf(4, 5)
4bac07c9 JF	205	int xenbus_watch_pathfmt(struct xenbus_device dev, struct xenbus_watch watch,
	206	void (callback)(struct xenbus_watch ,
	207	const char **, unsigned int),
b9075fa9	208	const char *pathfmt, ...);
4bac07c9 JF	209
	210	int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
	211	int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
	212	int xenbus_map_ring_valloc(struct xenbus_device *dev,
	213	int gnt_ref, void **vaddr);
	214	int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
	215	grant_handle_t handle, void vaddr);
	216
	217	int xenbus_unmap_ring_vfree(struct xenbus_device dev, void vaddr);
	218	int xenbus_unmap_ring(struct xenbus_device *dev,
	219	grant_handle_t handle, void *vaddr);
	220
	221	int xenbus_alloc_evtchn(struct xenbus_device dev, int port);
	222	int xenbus_bind_evtchn(struct xenbus_device dev, int remote_port, int port);
	223	int xenbus_free_evtchn(struct xenbus_device *dev, int port);
	224
	225	enum xenbus_state xenbus_read_driver_state(const char *path);
	226
b9075fa9	227	__printf(3, 4)
4bac07c9	228	void xenbus_dev_error(struct xenbus_device dev, int err, const char fmt, ...);
b9075fa9	229	__printf(3, 4)
4bac07c9 JF	230	void xenbus_dev_fatal(struct xenbus_device dev, int err, const char fmt, ...);
	231
	232	const char *xenbus_strstate(enum xenbus_state state);
	233	int xenbus_dev_is_online(struct xenbus_device *dev);
	234	int xenbus_frontend_closed(struct xenbus_device *dev);
	235
	236	#endif /* _XEN_XENBUS_H */