xenbus.h revision 1.2
1 /* $NetBSD: xenbus.h,v 1.2 2006/03/15 22:20:06 bouyer Exp $ */ 2 /****************************************************************************** 3 * xenbus.h 4 * 5 * Talks to Xen Store to figure out what devices we have. 6 * 7 * Copyright (C) 2005 Rusty Russell, IBM Corporation 8 * Copyright (C) 2005 XenSource Ltd. 9 * 10 * This file may be distributed separately from the Linux kernel, or 11 * incorporated into other software packages, subject to the following license: 12 * 13 * Permission is hereby granted, free of charge, to any person obtaining a copy 14 * of this source file (the "Software"), to deal in the Software without 15 * restriction, including without limitation the rights to use, copy, modify, 16 * merge, publish, distribute, sublicense, and/or sell copies of the Software, 17 * and to permit persons to whom the Software is furnished to do so, subject to 18 * the following conditions: 19 * 20 * The above copyright notice and this permission notice shall be included in 21 * all copies or substantial portions of the Software. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 25 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 26 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 29 * IN THE SOFTWARE. 30 */ 31 32 #ifndef _ASM_XEN_XENBUS_H 33 #define _ASM_XEN_XENBUS_H 34 35 #include <sys/device.h> 36 #include <sys/queue.h> 37 #include <machine/xen3-public/io/xenbus.h> 38 #include <machine/xen3-public/io/xs_wire.h> 39 40 /* xenbus to hypervisor attach */ 41 struct xenbus_attach_args { 42 const char *xa_device; 43 int xa_handle; 44 }; 45 46 /* devices to xenbus attach */ 47 struct xenbusdev_attach_args { 48 const char *xa_type; 49 int xa_id; 50 struct xenbus_device *xa_xbusd; 51 }; 52 53 /* Register callback to watch this node. */ 54 struct xenbus_watch 55 { 56 SLIST_ENTRY(xenbus_watch) watch_next; 57 58 /* Path being watched. */ 59 char *node; 60 61 /* Callback (executed in a process context with no locks held). */ 62 void (*xbw_callback)(struct xenbus_watch *, 63 const char **vec, unsigned int len); 64 struct xenbus_device *xbw_dev; 65 }; 66 67 68 /* A xenbus device. */ 69 struct xenbus_device { 70 const char xbusd_path[80]; /* our path */ 71 char *xbusd_otherend; /* the otherend path */ 72 int xbusd_otherend_id; /* the otherend's id */ 73 /* callback for otherend change */ 74 void (*xbusd_otherend_changed)(void *, XenbusState); 75 void *xbusd_data; 76 int xbusd_has_error; 77 /* for xenbus internal use */ 78 struct xenbus_watch xbusd_otherend_watch; 79 }; 80 81 struct xenbus_device_id 82 { 83 /* .../device/<device_type>/<identifier> */ 84 char devicetype[32]; /* General class of device. */ 85 }; 86 87 /* A xenbus driver. */ 88 struct xenbus_driver { 89 char *name; 90 struct module *owner; 91 const struct xenbus_device_id *ids; 92 int (*probe)(struct xenbus_device *dev, 93 const struct xenbus_device_id *id); 94 void (*otherend_changed)(struct xenbus_device *dev, 95 XenbusState backend_state); 96 int (*remove)(struct xenbus_device *dev); 97 int (*suspend)(struct xenbus_device *dev); 98 int (*resume)(struct xenbus_device *dev); 99 int (*hotplug)(struct xenbus_device *, char **, int, char *, int); 100 int (*read_otherend_details)(struct xenbus_device *dev); 101 }; 102 103 int xenbus_register_frontend(struct xenbus_driver *drv); 104 int xenbus_register_backend(struct xenbus_driver *drv); 105 void xenbus_unregister_driver(struct xenbus_driver *drv); 106 107 struct xenbus_transaction; 108 109 int xenbus_directory(struct xenbus_transaction *t, 110 const char *dir, const char *node, unsigned int *num, 111 char ***); 112 int xenbus_read(struct xenbus_transaction *t, 113 const char *dir, const char *node, unsigned int *len, 114 char **); 115 int xenbus_write(struct xenbus_transaction *t, 116 const char *dir, const char *node, const char *string); 117 int xenbus_mkdir(struct xenbus_transaction *t, 118 const char *dir, const char *node); 119 int xenbus_exists(struct xenbus_transaction *t, 120 const char *dir, const char *node); 121 int xenbus_rm(struct xenbus_transaction *t, const char *dir, const char *node); 122 struct xenbus_transaction *xenbus_transaction_start(void); 123 int xenbus_transaction_end(struct xenbus_transaction *t, int abort); 124 125 /* Single read and scanf: returns -errno or num scanned if > 0. */ 126 int xenbus_scanf(struct xenbus_transaction *t, 127 const char *dir, const char *node, const char *fmt, ...) 128 __attribute__((format(scanf, 4, 5))); 129 130 /* Single printf and write: returns -errno or 0. */ 131 int xenbus_printf(struct xenbus_transaction *t, 132 const char *dir, const char *node, const char *fmt, ...) 133 __attribute__((format(printf, 4, 5))); 134 135 /* Generic read function: NULL-terminated triples of name, 136 * sprintf-style type string, and pointer. Returns 0 or errno.*/ 137 int xenbus_gather(struct xenbus_transaction *t, const char *dir, ...); 138 139 /* notifer routines for when the xenstore comes up */ 140 // XXX int register_xenstore_notifier(struct notifier_block *nb); 141 // XXX void unregister_xenstore_notifier(struct notifier_block *nb); 142 143 int register_xenbus_watch(struct xenbus_watch *watch); 144 void unregister_xenbus_watch(struct xenbus_watch *watch); 145 void xs_suspend(void); 146 void xs_resume(void); 147 148 /* Used by xenbus_dev to borrow kernel's store connection. */ 149 int xenbus_dev_request_and_reply(struct xsd_sockmsg *msg, void **); 150 151 /* Called from xen core code. */ 152 void xenbus_suspend(void); 153 void xenbus_resume(void); 154 155 void xenbus_probe(void *); 156 157 #define XENBUS_IS_ERR_READ(str) ({ \ 158 if (!IS_ERR(str) && strlen(str) == 0) { \ 159 kfree(str); \ 160 str = ERR_PTR(-ERANGE); \ 161 } \ 162 IS_ERR(str); \ 163 }) 164 165 #define XENBUS_EXIST_ERR(err) ((err) == -ENOENT || (err) == -ERANGE) 166 167 168 /** 169 * Register a watch on the given path, using the given xenbus_watch structure 170 * for storage, and the given callback function as the callback. Return 0 on 171 * success, or -errno on error. On success, the given path will be saved as 172 * watch->node, and remains the caller's to free. On error, watch->node will 173 * be NULL, the device will switch to XenbusStateClosing, and the error will 174 * be saved in the store. 175 */ 176 int xenbus_watch_path(struct xenbus_device *dev, char *path, 177 struct xenbus_watch *watch, 178 void (*callback)(struct xenbus_watch *, 179 const char **, unsigned int)); 180 181 182 /** 183 * Register a watch on the given path/path2, using the given xenbus_watch 184 * structure for storage, and the given callback function as the callback. 185 * Return 0 on success, or -errno on error. On success, the watched path 186 * (path/path2) will be saved as watch->node, and becomes the caller's to 187 * kfree(). On error, watch->node will be NULL, so the caller has nothing to 188 * free, the device will switch to XenbusStateClosing, and the error will be 189 * saved in the store. 190 */ 191 int xenbus_watch_path2(struct xenbus_device *dev, const char *path, 192 const char *path2, struct xenbus_watch *watch, 193 void (*callback)(struct xenbus_watch *, 194 const char **, unsigned int)); 195 196 197 /** 198 * Advertise in the store a change of the given driver to the given new_state. 199 * Perform the change inside the given transaction xbt. xbt may be NULL, in 200 * which case this is performed inside its own transaction. Return 0 on 201 * success, or -errno on error. On error, the device will switch to 202 * XenbusStateClosing, and the error will be saved in the store. 203 */ 204 int xenbus_switch_state(struct xenbus_device *dev, 205 struct xenbus_transaction *xbt, 206 XenbusState new_state); 207 208 209 /** 210 * Grant access to the given ring_mfn to the peer of the given device. Return 211 * 0 on success, or -errno on error. On error, the device will switch to 212 * XenbusStateClosing, and the error will be saved in the store. 213 */ 214 int xenbus_grant_ring(struct xenbus_device *, paddr_t, grant_ref_t *); 215 216 217 /** 218 * Allocate an event channel for the given xenbus_device, assigning the newly 219 * created local port to *port. Return 0 on success, or -errno on error. On 220 * error, the device will switch to XenbusStateClosing, and the error will be 221 * saved in the store. 222 */ 223 int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port); 224 225 226 /** 227 * Return the state of the driver rooted at the given store path, or 228 * XenbusStateClosed if no state can be read. 229 */ 230 XenbusState xenbus_read_driver_state(const char *path); 231 232 233 /*** 234 * Report the given negative errno into the store, along with the given 235 * formatted message. 236 */ 237 void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, 238 ...); 239 240 241 /*** 242 * Equivalent to xenbus_dev_error(dev, err, fmt, args), followed by 243 * xenbus_switch_state(dev, NULL, XenbusStateClosing) to schedule an orderly 244 * closedown of this driver and its peer. 245 */ 246 void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, 247 ...); 248 249 250 #endif /* _ASM_XEN_XENBUS_H */ 251 252 /* 253 * Local variables: 254 * c-file-style: "linux" 255 * indent-tabs-mode: t 256 * c-indent-level: 8 257 * c-basic-offset: 8 258 * tab-width: 8 259 * End: 260 */ 261
Indexes created Wed Sep 24 05:09:52 GMT 2025