/****************************************************************************** * 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 file may be 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. * * $FreeBSD$ */ #ifndef _XEN_XENBUS_XENBUSVAR_H #define _XEN_XENBUS_XENBUSVAR_H #include #include #include #include #include #include #include "xenbus_if.h" enum { /* * Path of this device node. */ XENBUS_IVAR_NODE, /* * The device type (e.g. vif, vbd). */ XENBUS_IVAR_TYPE, /* * The state of this device (not the otherend's state). */ XENBUS_IVAR_STATE, /* * Domain ID of the other end device. */ XENBUS_IVAR_OTHEREND_ID, /* * Path of the other end device. */ XENBUS_IVAR_OTHEREND_PATH }; /* * Simplified accessors for xenbus devices */ #define XENBUS_ACCESSOR(var, ivar, type) \ __BUS_ACCESSOR(xenbus, var, XENBUS, ivar, type) XENBUS_ACCESSOR(node, NODE, const char *) XENBUS_ACCESSOR(type, TYPE, const char *) XENBUS_ACCESSOR(state, STATE, enum xenbus_state) XENBUS_ACCESSOR(otherend_id, OTHEREND_ID, int) XENBUS_ACCESSOR(otherend_path, OTHEREND_PATH, const char *) /* Register callback to watch this node. */ struct xenbus_watch { LIST_ENTRY(xenbus_watch) list; /* Path being watched. */ char *node; /* Callback (executed in a process context with no locks held). */ void (*callback)(struct xenbus_watch *, const char **vec, unsigned int len); }; typedef int (*xenstore_event_handler_t)(void *); struct xenbus_transaction { uint32_t id; }; #define XBT_NIL ((struct xenbus_transaction) { 0 }) int xenbus_directory(struct xenbus_transaction t, const char *dir, const char *node, unsigned int *num, char ***result); int xenbus_read(struct xenbus_transaction t, const char *dir, const char *node, unsigned int *len, void **result); 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 zero. If scancountp is * non-null, then number of items scanned is returned in *scanncountp. */ int xenbus_scanf(struct xenbus_transaction t, const char *dir, const char *node, int *scancountp, const char *fmt, ...) __attribute__((format(scanf, 5, 6))); /* 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 */ int register_xenstore_notifier(xenstore_event_handler_t func, void *arg, int priority); #if 0 void unregister_xenstore_notifier(); #endif int register_xenbus_watch(struct xenbus_watch *watch); void unregister_xenbus_watch(struct xenbus_watch *watch); void xs_suspend(void); void xs_resume(void); /* Used by xenbus_dev to borrow kernel's store connection. */ int xenbus_dev_request_and_reply(struct xsd_sockmsg *msg, void **result); #if 0 #define XENBUS_IS_ERR_READ(str) ({ \ if (!IS_ERR(str) && strlen(str) == 0) { \ free(str, M_DEVBUF); \ str = ERR_PTR(-ERANGE); \ } \ IS_ERR(str); \ }) #endif #define XENBUS_EXIST_ERR(err) ((err) == ENOENT || (err) == ERANGE) /** * Register a watch on the given path, using the given xenbus_watch structure * for storage, and the given callback function as the callback. Return 0 on * success, or errno on error. On success, the given path will be saved as * watch->node, and remains the caller's to free. On error, watch->node will * be NULL, the device will switch to XenbusStateClosing, and the error will * be saved in the store. */ int xenbus_watch_path(device_t dev, char *path, struct xenbus_watch *watch, void (*callback)(struct xenbus_watch *, const char **, unsigned int)); /** * Register a watch on the given path/path2, using the given xenbus_watch * structure for storage, and the given callback function as the callback. * Return 0 on success, or errno on error. On success, the watched path * (path/path2) will be saved as watch->node, and becomes the caller's to * kfree(). On error, watch->node will be NULL, so the caller has nothing to * free, the device will switch to XenbusStateClosing, and the error will be * saved in the store. */ int xenbus_watch_path2(device_t dev, const char *path, const char *path2, struct xenbus_watch *watch, void (*callback)(struct xenbus_watch *, const char **, unsigned int)); /** * Advertise in the store a change of the given driver to the given new_state. * which case this is performed inside its own transaction. Return 0 on * success, or errno on error. On error, the device will switch to * XenbusStateClosing, and the error will be saved in the store. */ int xenbus_switch_state(device_t dev, XenbusState new_state); /** * Grant access to the given ring_mfn to the peer of the given device. * Return 0 on success, or errno on error. On error, the device will * switch to XenbusStateClosing, and the error will be saved in the * store. The grant ring reference is returned in *refp. */ int xenbus_grant_ring(device_t dev, unsigned long ring_mfn, int *refp); /** * Allocate an event channel for the given xenbus_device, assigning the newly * created local port to *port. Return 0 on success, or errno on error. On * error, the device will switch to XenbusStateClosing, and the error will be * saved in the store. */ int xenbus_alloc_evtchn(device_t dev, int *port); /** * Free an existing event channel. Returns 0 on success or errno on error. */ int xenbus_free_evtchn(device_t dev, int port); /** * Return the state of the driver rooted at the given store path, or * XenbusStateClosed if no state can be read. */ XenbusState xenbus_read_driver_state(const char *path); /*** * Report the given negative errno into the store, along with the given * formatted message. */ void xenbus_dev_error(device_t dev, int err, const char *fmt, ...); /*** * Equivalent to xenbus_dev_error(dev, err, fmt, args), followed by * xenbus_switch_state(dev, NULL, XenbusStateClosing) to schedule an orderly * closedown of this driver and its peer. */ void xenbus_dev_fatal(device_t dev, int err, const char *fmt, ...); int xenbus_dev_init(void); const char *xenbus_strstate(enum xenbus_state state); int xenbus_dev_is_online(device_t dev); int xenbus_frontend_closed(device_t dev); #endif /* _XEN_XENBUS_XENBUSVAR_H */