/****************************************************************************** * 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/fs.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> #define XENBUS_MAX_RING_GRANT_ORDER 4 #define XENBUS_MAX_RING_GRANTS (1U << XENBUS_MAX_RING_GRANT_ORDER) #define INVALID_GRANT_HANDLE (~0U) /* 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 *path, const char *token); }; /* 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; struct work_struct work; }; 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 { const char *name; /* defaults to ids[0].devicetype */ 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); int __must_check __xenbus_register_backend(struct xenbus_driver *drv, struct module *owner, const char *mod_name); #define xenbus_register_frontend(drv) \ __xenbus_register_frontend(drv, THIS_MODULE, KBUILD_MODNAME) #define xenbus_register_backend(drv) \ __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. */ __scanf(4, 5) int xenbus_scanf(struct xenbus_transaction t, const char *dir, const char *node, const char *fmt, ...); /* Read an (optional) unsigned value. */ unsigned int xenbus_read_unsigned(const char *dir, const char *node, unsigned int default_val); /* 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); struct work_struct; void xenbus_probe(struct work_struct *); #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 *, const char *)); __printf(4, 5) int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch, void (*callback)(struct xenbus_watch *, const char *, const char *), const char *pathfmt, ...); int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state); int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr, unsigned int nr_pages, grant_ref_t *grefs); int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs, unsigned int nr_grefs, void **vaddr); int xenbus_map_ring(struct xenbus_device *dev, grant_ref_t *gnt_refs, unsigned int nr_grefs, grant_handle_t *handles, unsigned long *vaddrs, bool *leaked); int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr); int xenbus_unmap_ring(struct xenbus_device *dev, grant_handle_t *handles, unsigned int nr_handles, unsigned long *vaddrs); int xenbus_alloc_evtchn(struct xenbus_device *dev, 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); extern const struct file_operations xen_xenbus_fops; extern struct xenstore_domain_interface *xen_store_interface; extern int xen_store_evtchn; #endif /* _XEN_XENBUS_H */