| 1 | /* $NetBSD: xenbus_probe.c,v 1.39 2016/07/07 06:55:40 msaitoh Exp $ */ |
| 2 | /****************************************************************************** |
| 3 | * Talks to Xen Store to figure out what devices we have. |
| 4 | * |
| 5 | * Copyright (C) 2005 Rusty Russell, IBM Corporation |
| 6 | * Copyright (C) 2005 Mike Wray, Hewlett-Packard |
| 7 | * Copyright (C) 2005 XenSource Ltd |
| 8 | * |
| 9 | * This file may be distributed separately from the Linux kernel, or |
| 10 | * incorporated into other software packages, subject to the following license: |
| 11 | * |
| 12 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 13 | * of this source file (the "Software"), to deal in the Software without |
| 14 | * restriction, including without limitation the rights to use, copy, modify, |
| 15 | * merge, publish, distribute, sublicense, and/or sell copies of the Software, |
| 16 | * and to permit persons to whom the Software is furnished to do so, subject to |
| 17 | * the following conditions: |
| 18 | * |
| 19 | * The above copyright notice and this permission notice shall be included in |
| 20 | * all copies or substantial portions of the Software. |
| 21 | * |
| 22 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 23 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 24 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 25 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 26 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 27 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| 28 | * IN THE SOFTWARE. |
| 29 | */ |
| 30 | |
| 31 | #include <sys/cdefs.h> |
| 32 | __KERNEL_RCSID(0, "$NetBSD: xenbus_probe.c,v 1.39 2016/07/07 06:55:40 msaitoh Exp $" ); |
| 33 | |
| 34 | #if 0 |
| 35 | #define DPRINTK(fmt, args...) \ |
| 36 | printf("xenbus_probe (%s:%d) " fmt ".\n", __func__, __LINE__, ##args) |
| 37 | #else |
| 38 | #define DPRINTK(fmt, args...) ((void)0) |
| 39 | #endif |
| 40 | |
| 41 | #include <sys/types.h> |
| 42 | #include <sys/null.h> |
| 43 | #include <sys/errno.h> |
| 44 | #include <sys/malloc.h> |
| 45 | #include <sys/systm.h> |
| 46 | #include <sys/param.h> |
| 47 | #include <sys/kthread.h> |
| 48 | #include <uvm/uvm.h> |
| 49 | |
| 50 | #include <xen/xen.h> /* for xendomain_is_dom0() */ |
| 51 | #include <xen/hypervisor.h> |
| 52 | #include <xen/xenbus.h> |
| 53 | #include <xen/evtchn.h> |
| 54 | #include <xen/shutdown_xenbus.h> |
| 55 | |
| 56 | #include "xenbus_comms.h" |
| 57 | |
| 58 | extern struct semaphore xenwatch_mutex; |
| 59 | |
| 60 | #define streq(a, b) (strcmp((a), (b)) == 0) |
| 61 | |
| 62 | static int xenbus_match(device_t, cfdata_t, void *); |
| 63 | static void xenbus_attach(device_t, device_t, void *); |
| 64 | static int xenbus_print(void *, const char *); |
| 65 | |
| 66 | /* power management, for save/restore */ |
| 67 | static bool xenbus_suspend(device_t, const pmf_qual_t *); |
| 68 | static bool xenbus_resume(device_t, const pmf_qual_t *); |
| 69 | |
| 70 | /* routines gathering device information from XenStore */ |
| 71 | static int read_otherend_details(struct xenbus_device *, |
| 72 | const char *, const char *); |
| 73 | static int read_backend_details (struct xenbus_device *); |
| 74 | static int read_frontend_details(struct xenbus_device *); |
| 75 | static void free_otherend_details(struct xenbus_device *); |
| 76 | |
| 77 | static int watch_otherend (struct xenbus_device *); |
| 78 | static void free_otherend_watch(struct xenbus_device *); |
| 79 | |
| 80 | static void xenbus_probe_init(void *); |
| 81 | |
| 82 | static struct xenbus_device *xenbus_lookup_device_path(const char *); |
| 83 | |
| 84 | CFATTACH_DECL_NEW(xenbus, 0, xenbus_match, xenbus_attach, |
| 85 | NULL, NULL); |
| 86 | |
| 87 | device_t xenbus_dev; |
| 88 | |
| 89 | SLIST_HEAD(, xenbus_device) xenbus_device_list; |
| 90 | SLIST_HEAD(, xenbus_backend_driver) xenbus_backend_driver_list = |
| 91 | SLIST_HEAD_INITIALIZER(xenbus_backend_driver); |
| 92 | |
| 93 | int |
| 94 | xenbus_match(device_t parent, cfdata_t match, void *aux) |
| 95 | { |
| 96 | struct xenbus_attach_args *xa = (struct xenbus_attach_args *)aux; |
| 97 | |
| 98 | if (strcmp(xa->xa_device, "xenbus" ) == 0) |
| 99 | return 1; |
| 100 | return 0; |
| 101 | } |
| 102 | |
| 103 | static void |
| 104 | xenbus_attach(device_t parent, device_t self, void *aux) |
| 105 | { |
| 106 | int err; |
| 107 | |
| 108 | aprint_normal(": Xen Virtual Bus Interface\n" ); |
| 109 | xenbus_dev = self; |
| 110 | config_pending_incr(self); |
| 111 | |
| 112 | err = kthread_create(PRI_NONE, 0, NULL, xenbus_probe_init, NULL, |
| 113 | NULL, "xenbus_probe" ); |
| 114 | if (err) |
| 115 | aprint_error_dev(xenbus_dev, |
| 116 | "kthread_create(xenbus_probe): %d\n" , err); |
| 117 | |
| 118 | if (!pmf_device_register(self, xenbus_suspend, xenbus_resume)) |
| 119 | aprint_error_dev(self, "couldn't establish power handler\n" ); |
| 120 | } |
| 121 | |
| 122 | static bool |
| 123 | xenbus_suspend(device_t dev, const pmf_qual_t *qual) |
| 124 | { |
| 125 | xs_suspend(); |
| 126 | xb_suspend_comms(dev); |
| 127 | |
| 128 | return true; |
| 129 | } |
| 130 | |
| 131 | static bool |
| 132 | xenbus_resume(device_t dev, const pmf_qual_t *qual) |
| 133 | { |
| 134 | xb_init_comms(dev); |
| 135 | xs_resume(); |
| 136 | |
| 137 | return true; |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * Suspend a xenbus device |
| 142 | */ |
| 143 | bool |
| 144 | xenbus_device_suspend(struct xenbus_device *dev) { |
| 145 | |
| 146 | free_otherend_details(dev); |
| 147 | return true; |
| 148 | } |
| 149 | |
| 150 | /* |
| 151 | * Resume a xenbus device |
| 152 | */ |
| 153 | bool |
| 154 | xenbus_device_resume(struct xenbus_device *dev) { |
| 155 | |
| 156 | if (dev->xbusd_type == XENBUS_FRONTEND_DEVICE) { |
| 157 | read_backend_details(dev); |
| 158 | } |
| 159 | |
| 160 | return true; |
| 161 | } |
| 162 | |
| 163 | void |
| 164 | xenbus_backend_register(struct xenbus_backend_driver *xbakd) |
| 165 | { |
| 166 | SLIST_INSERT_HEAD(&xenbus_backend_driver_list, xbakd, xbakd_entries); |
| 167 | } |
| 168 | |
| 169 | static int |
| 170 | read_otherend_details(struct xenbus_device *xendev, |
| 171 | const char *id_node, const char *path_node) |
| 172 | { |
| 173 | int err; |
| 174 | char *val, *ep; |
| 175 | |
| 176 | err = xenbus_read(NULL, xendev->xbusd_path, id_node, NULL, &val); |
| 177 | if (err) { |
| 178 | printf("reading other end details %s from %s\n" , |
| 179 | id_node, xendev->xbusd_path); |
| 180 | xenbus_dev_fatal(xendev, err, |
| 181 | "reading other end details %s from %s" , |
| 182 | id_node, xendev->xbusd_path); |
| 183 | return err; |
| 184 | } |
| 185 | xendev->xbusd_otherend_id = strtoul(val, &ep, 10); |
| 186 | if (val[0] == '\0' || *ep != '\0') { |
| 187 | printf("reading other end details %s from %s: %s is not a number\n" , id_node, xendev->xbusd_path, val); |
| 188 | xenbus_dev_fatal(xendev, err, |
| 189 | "reading other end details %s from %s: %s is not a number" , |
| 190 | id_node, xendev->xbusd_path, val); |
| 191 | free(val, M_DEVBUF); |
| 192 | return EFTYPE; |
| 193 | } |
| 194 | free(val, M_DEVBUF); |
| 195 | err = xenbus_read(NULL, xendev->xbusd_path, path_node, NULL, &val); |
| 196 | if (err) { |
| 197 | printf("reading other end details %s from %s (%d)\n" , |
| 198 | path_node, xendev->xbusd_path, err); |
| 199 | xenbus_dev_fatal(xendev, err, |
| 200 | "reading other end details %s from %s" , |
| 201 | path_node, xendev->xbusd_path); |
| 202 | return err; |
| 203 | } |
| 204 | DPRINTK("read_otherend_details: read %s/%s returned %s\n" , |
| 205 | xendev->xbusd_path, path_node, val); |
| 206 | xendev->xbusd_otherend = val; |
| 207 | |
| 208 | if (strlen(xendev->xbusd_otherend) == 0 || |
| 209 | !xenbus_exists(NULL, xendev->xbusd_otherend, "" )) { |
| 210 | printf("missing other end from %s\n" , xendev->xbusd_path); |
| 211 | xenbus_dev_fatal(xendev, -ENOENT, "missing other end from %s" , |
| 212 | xendev->xbusd_path); |
| 213 | free_otherend_details(xendev); |
| 214 | return ENOENT; |
| 215 | } |
| 216 | |
| 217 | return 0; |
| 218 | } |
| 219 | |
| 220 | static int |
| 221 | read_backend_details(struct xenbus_device *xendev) |
| 222 | { |
| 223 | return read_otherend_details(xendev, "backend-id" , "backend" ); |
| 224 | } |
| 225 | |
| 226 | |
| 227 | static int |
| 228 | read_frontend_details(struct xenbus_device *xendev) |
| 229 | { |
| 230 | return read_otherend_details(xendev, "frontend-id" , "frontend" ); |
| 231 | } |
| 232 | |
| 233 | static void |
| 234 | free_otherend_details(struct xenbus_device *dev) |
| 235 | { |
| 236 | free(dev->xbusd_otherend, M_DEVBUF); |
| 237 | dev->xbusd_otherend = NULL; |
| 238 | } |
| 239 | |
| 240 | static void |
| 241 | free_otherend_watch(struct xenbus_device *dev) |
| 242 | { |
| 243 | if (dev->xbusd_otherend_watch.node) { |
| 244 | unregister_xenbus_watch(&dev->xbusd_otherend_watch); |
| 245 | free(dev->xbusd_otherend_watch.node, M_DEVBUF); |
| 246 | dev->xbusd_otherend_watch.node = NULL; |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | static void |
| 251 | otherend_changed(struct xenbus_watch *watch, |
| 252 | const char **vec, unsigned int len) |
| 253 | { |
| 254 | struct xenbus_device *xdev = watch->xbw_dev; |
| 255 | XenbusState state; |
| 256 | |
| 257 | /* Protect us against watches firing on old details when the otherend |
| 258 | details change, say immediately after a resume. */ |
| 259 | if (!xdev->xbusd_otherend || |
| 260 | strncmp(xdev->xbusd_otherend, vec[XS_WATCH_PATH], |
| 261 | strlen(xdev->xbusd_otherend))) { |
| 262 | DPRINTK("Ignoring watch at %s" , vec[XS_WATCH_PATH]); |
| 263 | return; |
| 264 | } |
| 265 | |
| 266 | state = xenbus_read_driver_state(xdev->xbusd_otherend); |
| 267 | |
| 268 | DPRINTK("state is %d, %s, %s" , |
| 269 | state, xdev->xbusd_otherend_watch.node, vec[XS_WATCH_PATH]); |
| 270 | if (state == XenbusStateClosed) { |
| 271 | int error; |
| 272 | if (xdev->xbusd_type == XENBUS_BACKEND_DEVICE) { |
| 273 | error = xdev->xbusd_u.b.b_detach( |
| 274 | xdev->xbusd_u.b.b_cookie); |
| 275 | if (error) { |
| 276 | printf("could not detach %s: %d\n" , |
| 277 | xdev->xbusd_path, error); |
| 278 | return; |
| 279 | } |
| 280 | } else { |
| 281 | error = config_detach(xdev->xbusd_u.f.f_dev, |
| 282 | DETACH_FORCE); |
| 283 | if (error) { |
| 284 | printf("could not detach %s: %d\n" , |
| 285 | device_xname(xdev->xbusd_u.f.f_dev), error); |
| 286 | return; |
| 287 | } |
| 288 | } |
| 289 | xenbus_free_device(xdev); |
| 290 | return; |
| 291 | } |
| 292 | if (xdev->xbusd_otherend_changed) |
| 293 | xdev->xbusd_otherend_changed( |
| 294 | (xdev->xbusd_type == XENBUS_BACKEND_DEVICE) ? |
| 295 | xdev->xbusd_u.b.b_cookie : xdev->xbusd_u.f.f_dev, state); |
| 296 | } |
| 297 | |
| 298 | static int |
| 299 | watch_otherend(struct xenbus_device *dev) |
| 300 | { |
| 301 | free_otherend_watch(dev); |
| 302 | |
| 303 | return xenbus_watch_path2(dev, dev->xbusd_otherend, "state" , |
| 304 | &dev->xbusd_otherend_watch, |
| 305 | otherend_changed); |
| 306 | } |
| 307 | |
| 308 | static struct xenbus_device * |
| 309 | xenbus_lookup_device_path(const char *path) |
| 310 | { |
| 311 | struct xenbus_device *xbusd; |
| 312 | |
| 313 | SLIST_FOREACH(xbusd, &xenbus_device_list, xbusd_entries) { |
| 314 | if (strcmp(xbusd->xbusd_path, path) == 0) |
| 315 | return xbusd; |
| 316 | } |
| 317 | return NULL; |
| 318 | } |
| 319 | |
| 320 | static int |
| 321 | xenbus_probe_device_type(const char *path, const char *type, |
| 322 | int (*create)(struct xenbus_device *)) |
| 323 | { |
| 324 | int err, i, pos, msize; |
| 325 | int *lookup = NULL; |
| 326 | unsigned long state; |
| 327 | char **dir; |
| 328 | unsigned int dir_n = 0; |
| 329 | struct xenbus_device *xbusd; |
| 330 | struct xenbusdev_attach_args xa; |
| 331 | char *ep; |
| 332 | |
| 333 | DPRINTK("probe %s type %s" , path, type); |
| 334 | err = xenbus_directory(NULL, path, "" , &dir_n, &dir); |
| 335 | DPRINTK("directory err %d dir_n %d" , err, dir_n); |
| 336 | if (err) |
| 337 | return err; |
| 338 | |
| 339 | /* Only sort frontend devices i.e. create == NULL*/ |
| 340 | if (dir_n > 1 && create == NULL) { |
| 341 | int minp; |
| 342 | unsigned long minv; |
| 343 | unsigned long *id; |
| 344 | |
| 345 | lookup = malloc(sizeof(int) * dir_n, M_DEVBUF, |
| 346 | M_WAITOK | M_ZERO); |
| 347 | if (lookup == NULL) |
| 348 | panic("can't malloc lookup" ); |
| 349 | |
| 350 | id = malloc(sizeof(unsigned long) * dir_n, M_DEVBUF, |
| 351 | M_WAITOK | M_ZERO); |
| 352 | if (id == NULL) |
| 353 | panic("can't malloc id" ); |
| 354 | |
| 355 | /* Convert string values to numeric; skip invalid */ |
| 356 | for (i = 0; i < dir_n; i++) { |
| 357 | /* |
| 358 | * Add one to differentiate numerical zero from invalid |
| 359 | * string. Has no effect on sort order. |
| 360 | */ |
| 361 | id[i] = strtoul(dir[i], &ep, 10) + 1; |
| 362 | if (dir[i][0] == '\0' || *ep != '\0') |
| 363 | id[i] = 0; |
| 364 | } |
| 365 | |
| 366 | /* Build lookup table in ascending order */ |
| 367 | for (pos = 0; pos < dir_n; ) { |
| 368 | minv = UINT32_MAX; |
| 369 | minp = -1; |
| 370 | for (i = 0; i < dir_n; i++) { |
| 371 | if (id[i] < minv && id[i] > 0) { |
| 372 | minv = id[i]; |
| 373 | minp = i; |
| 374 | } |
| 375 | } |
| 376 | if (minp >= 0) { |
| 377 | lookup[pos++] = minp; |
| 378 | id[minp] = 0; |
| 379 | } |
| 380 | else |
| 381 | break; |
| 382 | } |
| 383 | |
| 384 | free(id, M_DEVBUF); |
| 385 | /* Adjust in case we had to skip non-numeric entries */ |
| 386 | dir_n = pos; |
| 387 | } |
| 388 | |
| 389 | for (pos = 0; pos < dir_n; pos++) { |
| 390 | err = 0; |
| 391 | if (lookup) |
| 392 | i = lookup[pos]; |
| 393 | else |
| 394 | i = pos; |
| 395 | /* |
| 396 | * add size of path to size of xenbus_device. xenbus_device |
| 397 | * already has room for one char in xbusd_path. |
| 398 | */ |
| 399 | msize = sizeof(*xbusd) + strlen(path) + strlen(dir[i]) + 2; |
| 400 | xbusd = malloc(msize, M_DEVBUF, M_WAITOK | M_ZERO); |
| 401 | if (xbusd == NULL) |
| 402 | panic("can't malloc xbusd" ); |
| 403 | |
| 404 | snprintf(__UNCONST(xbusd->xbusd_path), |
| 405 | msize - sizeof(*xbusd) + 1, "%s/%s" , path, dir[i]); |
| 406 | if (xenbus_lookup_device_path(xbusd->xbusd_path) != NULL) { |
| 407 | /* device already registered */ |
| 408 | free(xbusd, M_DEVBUF); |
| 409 | continue; |
| 410 | } |
| 411 | err = xenbus_read_ul(NULL, xbusd->xbusd_path, "state" , |
| 412 | &state, 10); |
| 413 | if (err) { |
| 414 | printf("xenbus: can't get state " |
| 415 | "for %s (%d)\n" , xbusd->xbusd_path, err); |
| 416 | free(xbusd, M_DEVBUF); |
| 417 | err = 0; |
| 418 | continue; |
| 419 | } |
| 420 | if (state != XenbusStateInitialising) { |
| 421 | /* device is not new */ |
| 422 | free(xbusd, M_DEVBUF); |
| 423 | continue; |
| 424 | } |
| 425 | |
| 426 | xbusd->xbusd_otherend_watch.xbw_dev = xbusd; |
| 427 | DPRINTK("xenbus_probe_device_type probe %s\n" , |
| 428 | xbusd->xbusd_path); |
| 429 | if (create != NULL) { |
| 430 | xbusd->xbusd_type = XENBUS_BACKEND_DEVICE; |
| 431 | err = read_frontend_details(xbusd); |
| 432 | if (err != 0) { |
| 433 | printf("xenbus: can't get frontend details " |
| 434 | "for %s (%d)\n" , xbusd->xbusd_path, err); |
| 435 | break; |
| 436 | } |
| 437 | if (create(xbusd)) { |
| 438 | free(xbusd, M_DEVBUF); |
| 439 | continue; |
| 440 | } |
| 441 | } else { |
| 442 | xbusd->xbusd_type = XENBUS_FRONTEND_DEVICE; |
| 443 | xa.xa_xbusd = xbusd; |
| 444 | xa.xa_type = type; |
| 445 | xa.xa_id = strtoul(dir[i], &ep, 0); |
| 446 | if (dir[i][0] == '\0' || *ep != '\0') { |
| 447 | printf("xenbus device type %s: id %s is not a" |
| 448 | " number\n" , type, dir[i]); |
| 449 | err = EFTYPE; |
| 450 | free(xbusd, M_DEVBUF); |
| 451 | break; |
| 452 | } |
| 453 | err = read_backend_details(xbusd); |
| 454 | if (err != 0) { |
| 455 | printf("xenbus: can't get backend details " |
| 456 | "for %s (%d)\n" , xbusd->xbusd_path, err); |
| 457 | break; |
| 458 | } |
| 459 | xbusd->xbusd_u.f.f_dev = config_found_ia(xenbus_dev, |
| 460 | "xenbus" , &xa, xenbus_print); |
| 461 | if (xbusd->xbusd_u.f.f_dev == NULL) { |
| 462 | free(xbusd, M_DEVBUF); |
| 463 | continue; |
| 464 | } |
| 465 | } |
| 466 | SLIST_INSERT_HEAD(&xenbus_device_list, |
| 467 | xbusd, xbusd_entries); |
| 468 | watch_otherend(xbusd); |
| 469 | } |
| 470 | free(dir, M_DEVBUF); |
| 471 | if (lookup) |
| 472 | free(lookup, M_DEVBUF); |
| 473 | |
| 474 | return err; |
| 475 | } |
| 476 | |
| 477 | static int |
| 478 | xenbus_print(void *aux, const char *pnp) |
| 479 | { |
| 480 | struct xenbusdev_attach_args *xa = aux; |
| 481 | |
| 482 | if (pnp) { |
| 483 | if (strcmp(xa->xa_type, "vbd" ) == 0) |
| 484 | aprint_normal("xbd" ); |
| 485 | else if (strcmp(xa->xa_type, "vif" ) == 0) |
| 486 | aprint_normal("xennet" ); |
| 487 | else if (strcmp(xa->xa_type, "balloon" ) == 0) |
| 488 | aprint_normal("balloon" ); |
| 489 | else |
| 490 | aprint_normal("unknown type %s" , xa->xa_type); |
| 491 | aprint_normal(" at %s" , pnp); |
| 492 | } |
| 493 | aprint_normal(" id %d" , xa->xa_id); |
| 494 | return(UNCONF); |
| 495 | } |
| 496 | |
| 497 | static int |
| 498 | xenbus_probe_frontends(void) |
| 499 | { |
| 500 | int err; |
| 501 | char **dir; |
| 502 | unsigned int i, dir_n; |
| 503 | char path[30]; |
| 504 | |
| 505 | DPRINTK("probe device" ); |
| 506 | err = xenbus_directory(NULL, "device" , "" , &dir_n, &dir); |
| 507 | DPRINTK("directory err %d dir_n %d" , err, dir_n); |
| 508 | if (err) |
| 509 | return err; |
| 510 | |
| 511 | for (i = 0; i < dir_n; i++) { |
| 512 | /* |
| 513 | * console is configured through xen_start_info when |
| 514 | * xencons is attaching to hypervisor, so avoid console |
| 515 | * probing when configuring xenbus devices |
| 516 | */ |
| 517 | if (strcmp(dir[i], "console" ) == 0) |
| 518 | continue; |
| 519 | |
| 520 | snprintf(path, sizeof(path), "device/%s" , dir[i]); |
| 521 | err = xenbus_probe_device_type(path, dir[i], NULL); |
| 522 | if (err) |
| 523 | break; |
| 524 | } |
| 525 | free(dir, M_DEVBUF); |
| 526 | return err; |
| 527 | } |
| 528 | |
| 529 | static int |
| 530 | xenbus_probe_backends(void) |
| 531 | { |
| 532 | int err; |
| 533 | char **dirt, **dirid; |
| 534 | unsigned int type, id, dirt_n, dirid_n; |
| 535 | char path[30]; |
| 536 | struct xenbus_backend_driver *xbakd; |
| 537 | |
| 538 | DPRINTK("probe backend" ); |
| 539 | err = xenbus_directory(NULL, "backend" , "" , &dirt_n, &dirt); |
| 540 | DPRINTK("directory err %d dirt_n %d" , err, dirt_n); |
| 541 | if (err) |
| 542 | return err; |
| 543 | |
| 544 | for (type = 0; type < dirt_n; type++) { |
| 545 | SLIST_FOREACH(xbakd, &xenbus_backend_driver_list, |
| 546 | xbakd_entries) { |
| 547 | if (strcmp(dirt[type], xbakd->xbakd_type) == 0) |
| 548 | break; |
| 549 | } |
| 550 | if (xbakd == NULL) |
| 551 | continue; |
| 552 | err = xenbus_directory(NULL, "backend" , dirt[type], |
| 553 | &dirid_n, &dirid); |
| 554 | DPRINTK("directory backend/%s err %d dirid_n %d" , |
| 555 | dirt[type], err, dirid_n); |
| 556 | if (err) { |
| 557 | free(dirt, M_DEVBUF); /* to be checked */ |
| 558 | return err; |
| 559 | } |
| 560 | for (id = 0; id < dirid_n; id++) { |
| 561 | snprintf(path, sizeof(path), "backend/%s/%s" , |
| 562 | dirt[type], dirid[id]); |
| 563 | err = xenbus_probe_device_type(path, dirt[type], |
| 564 | xbakd->xbakd_create); |
| 565 | if (err) |
| 566 | break; |
| 567 | } |
| 568 | free(dirid, M_DEVBUF); |
| 569 | } |
| 570 | free(dirt, M_DEVBUF); |
| 571 | return err; |
| 572 | } |
| 573 | |
| 574 | int |
| 575 | xenbus_free_device(struct xenbus_device *xbusd) |
| 576 | { |
| 577 | KASSERT(xenbus_lookup_device_path(xbusd->xbusd_path) == xbusd); |
| 578 | SLIST_REMOVE(&xenbus_device_list, xbusd, xenbus_device, xbusd_entries); |
| 579 | free_otherend_watch(xbusd); |
| 580 | free_otherend_details(xbusd); |
| 581 | xenbus_switch_state(xbusd, NULL, XenbusStateClosed); |
| 582 | free(xbusd, M_DEVBUF); |
| 583 | return 0; |
| 584 | } |
| 585 | |
| 586 | static void |
| 587 | frontend_changed(struct xenbus_watch *watch, |
| 588 | const char **vec, unsigned int len) |
| 589 | { |
| 590 | DPRINTK("frontend_changed %s\n" , vec[XS_WATCH_PATH]); |
| 591 | xenbus_probe_frontends(); |
| 592 | } |
| 593 | |
| 594 | static void |
| 595 | backend_changed(struct xenbus_watch *watch, |
| 596 | const char **vec, unsigned int len) |
| 597 | { |
| 598 | DPRINTK("backend_changed %s\n" , vec[XS_WATCH_PATH]); |
| 599 | xenbus_probe_backends(); |
| 600 | } |
| 601 | |
| 602 | |
| 603 | /* We watch for devices appearing and vanishing. */ |
| 604 | static struct xenbus_watch fe_watch; |
| 605 | |
| 606 | static struct xenbus_watch be_watch; |
| 607 | |
| 608 | /* A flag to determine if xenstored is 'ready' (i.e. has started) */ |
| 609 | int xenstored_ready = 0; |
| 610 | |
| 611 | void |
| 612 | xenbus_probe(void *unused) |
| 613 | { |
| 614 | struct xenbusdev_attach_args balloon_xa = { |
| 615 | .xa_id = 0, |
| 616 | .xa_type = "balloon" |
| 617 | }; |
| 618 | |
| 619 | KASSERT((xenstored_ready > 0)); |
| 620 | |
| 621 | /* Enumerate devices in xenstore. */ |
| 622 | xenbus_probe_frontends(); |
| 623 | xenbus_probe_backends(); |
| 624 | |
| 625 | /* Watch for changes. */ |
| 626 | fe_watch.node = malloc(strlen("device" + 1), M_DEVBUF, M_NOWAIT); |
| 627 | strcpy(fe_watch.node, "device" ); |
| 628 | fe_watch.xbw_callback = frontend_changed; |
| 629 | register_xenbus_watch(&fe_watch); |
| 630 | be_watch.node = malloc(strlen("backend" + 1), M_DEVBUF, M_NOWAIT); |
| 631 | strcpy(be_watch.node, "backend" ); |
| 632 | be_watch.xbw_callback = backend_changed; |
| 633 | register_xenbus_watch(&be_watch); |
| 634 | |
| 635 | /* attach balloon. */ |
| 636 | config_found_ia(xenbus_dev, "xenbus" , &balloon_xa, xenbus_print); |
| 637 | |
| 638 | shutdown_xenbus_setup(); |
| 639 | |
| 640 | /* Notify others that xenstore is up */ |
| 641 | //notifier_call_chain(&xenstore_chain, 0, NULL); |
| 642 | } |
| 643 | |
| 644 | static void |
| 645 | xenbus_probe_init(void *unused) |
| 646 | { |
| 647 | int err = 0; |
| 648 | bool dom0; |
| 649 | vaddr_t page = 0; |
| 650 | |
| 651 | DPRINTK("" ); |
| 652 | |
| 653 | SLIST_INIT(&xenbus_device_list); |
| 654 | |
| 655 | /* |
| 656 | ** Domain0 doesn't have a store_evtchn or store_mfn yet. |
| 657 | */ |
| 658 | dom0 = xendomain_is_dom0(); |
| 659 | if (dom0) { |
| 660 | #if defined(DOM0OPS) |
| 661 | paddr_t ma; |
| 662 | evtchn_op_t op = { .cmd = 0 }; |
| 663 | |
| 664 | /* Allocate page. */ |
| 665 | page = uvm_km_alloc(kernel_map, PAGE_SIZE, 0, |
| 666 | UVM_KMF_ZERO | UVM_KMF_WIRED); |
| 667 | if (!page) |
| 668 | panic("can't get xenstore page" ); |
| 669 | |
| 670 | (void)pmap_extract_ma(pmap_kernel(), page, &ma); |
| 671 | xen_start_info.store_mfn = ma >> PAGE_SHIFT; |
| 672 | xenstore_interface = (void *)page; |
| 673 | |
| 674 | /* Next allocate a local port which xenstored can bind to */ |
| 675 | op.cmd = EVTCHNOP_alloc_unbound; |
| 676 | op.u.alloc_unbound.dom = DOMID_SELF; |
| 677 | op.u.alloc_unbound.remote_dom = 0; |
| 678 | |
| 679 | err = HYPERVISOR_event_channel_op(&op); |
| 680 | if (err) { |
| 681 | aprint_error_dev(xenbus_dev, |
| 682 | "can't register xenstore event\n" ); |
| 683 | goto err0; |
| 684 | } |
| 685 | |
| 686 | xen_start_info.store_evtchn = op.u.alloc_unbound.port; |
| 687 | |
| 688 | DELAY(1000); |
| 689 | #else /* DOM0OPS */ |
| 690 | kthread_exit(0); /* can't get a working xenstore in this case */ |
| 691 | #endif /* DOM0OPS */ |
| 692 | } |
| 693 | |
| 694 | /* Publish xenbus and Xenstore info in /kern/xen */ |
| 695 | xenbus_kernfs_init(); |
| 696 | |
| 697 | /* register event handler */ |
| 698 | xb_init_comms(xenbus_dev); |
| 699 | |
| 700 | /* Initialize the interface to xenstore. */ |
| 701 | err = xs_init(xenbus_dev); |
| 702 | if (err) { |
| 703 | aprint_error_dev(xenbus_dev, |
| 704 | "Error initializing xenstore comms: %i\n" , err); |
| 705 | goto err0; |
| 706 | } |
| 707 | |
| 708 | if (!dom0) { |
| 709 | xenstored_ready = 1; |
| 710 | xenbus_probe(NULL); |
| 711 | } |
| 712 | |
| 713 | DPRINTK("done" ); |
| 714 | config_pending_decr(xenbus_dev); |
| 715 | #ifdef DOM0OPS |
| 716 | if (dom0) { |
| 717 | int s; |
| 718 | s = spltty(); |
| 719 | while (xenstored_ready == 0) { |
| 720 | tsleep(&xenstored_ready, PRIBIO, "xsready" , 0); |
| 721 | xenbus_probe(NULL); |
| 722 | } |
| 723 | splx(s); |
| 724 | } |
| 725 | #endif |
| 726 | kthread_exit(0); |
| 727 | |
| 728 | err0: |
| 729 | if (page) |
| 730 | uvm_km_free(kernel_map, page, PAGE_SIZE, |
| 731 | UVM_KMF_ZERO | UVM_KMF_WIRED); |
| 732 | kthread_exit(err); |
| 733 | } |
| 734 | |
| 735 | /* |
| 736 | * Local variables: |
| 737 | * c-file-style: "linux" |
| 738 | * indent-tabs-mode: t |
| 739 | * c-indent-level: 8 |
| 740 | * c-basic-offset: 8 |
| 741 | * tab-width: 8 |
| 742 | * End: |
| 743 | */ |
| 744 | |