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Diffstat (limited to 'include/xen/xenbus.h')
| -rw-r--r-- | include/xen/xenbus.h | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h new file mode 100644 index 000000000..ac22cf08c --- /dev/null +++ b/include/xen/xenbus.h @@ -0,0 +1,251 @@ +/****************************************************************************** + * 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 <linux/semaphore.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> +#include <xen/interface/event_channel.h> + +#define XENBUS_MAX_RING_GRANT_ORDER 4 +#define XENBUS_MAX_RING_GRANTS (1U << XENBUS_MAX_RING_GRANT_ORDER) + +/* Register callback to watch this node. */ +struct xenbus_watch +{ + struct list_head list; + + /* Path being watched. */ + const char *node; + + unsigned int nr_pending; + + /* + * Called just before enqueing new event while a spinlock is held. + * The event will be discarded if this callback returns false. + */ + bool (*will_handle)(struct xenbus_watch *, + const char *path, const char *token); + + /* 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; + struct semaphore reclaim_sem; + + /* Event channel based statistics and settings. */ + atomic_t event_channels; + atomic_t events; + atomic_t spurious_events; + atomic_t jiffies_eoi_delayed; + unsigned int spurious_threshold; +}; + +#define to_xenbus_device(__dev) container_of_const(__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; + bool allow_rebind; /* avoid setting xenstore closed during remove */ + bool not_essential; /* is not mandatory for boot progress */ + int (*probe)(struct xenbus_device *dev, + const struct xenbus_device_id *id); + void (*otherend_changed)(struct xenbus_device *dev, + enum xenbus_state backend_state); + void (*remove)(struct xenbus_device *dev); + int (*suspend)(struct xenbus_device *dev); + int (*resume)(struct xenbus_device *dev); + int (*uevent)(const 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); + void (*reclaim_memory)(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; + +#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, + bool (*will_handle)(struct xenbus_watch *, + const char *, const char *), + void (*callback)(struct xenbus_watch *, + const char *, const char *)); +__printf(5, 6) +int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch, + bool (*will_handle)(struct xenbus_watch *, + const char *, const char *), + 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_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr, + unsigned int nr_pages, grant_ref_t *grefs); +void xenbus_teardown_ring(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_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr); + +int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port); +int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t 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 */ |