| 1 | /* |
| 2 | * Copyright (c) 2012 The DragonFly Project. All rights reserved. |
| 3 | * |
| 4 | * This code is derived from software contributed to The DragonFly Project |
| 5 | * by Matthew Dillon <dillon@dragonflybsd.org> |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * |
| 11 | * 1. Redistributions of source code must retain the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer. |
| 13 | * 2. Redistributions in binary form must reproduce the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer in |
| 15 | * the documentation and/or other materials provided with the |
| 16 | * distribution. |
| 17 | * 3. Neither the name of The DragonFly Project nor the names of its |
| 18 | * contributors may be used to endorse or promote products derived |
| 19 | * from this software without specific, prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 22 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 23 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 24 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 25 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 26 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 27 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 28 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 29 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 30 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 31 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 32 | * SUCH DAMAGE. |
| 33 | */ |
| 34 | /* |
| 35 | * LNK_SPAN PROTOCOL SUPPORT FUNCTIONS - Please see sys/dmsg.h for an |
| 36 | * involved explanation of the protocol. |
| 37 | */ |
| 38 | |
| 39 | #include "dmsg_local.h" |
| 40 | |
| 41 | void (*dmsg_node_handler)(void **opaquep, struct dmsg_msg *msg, int op); |
| 42 | |
| 43 | /* |
| 44 | * Maximum spanning tree distance. This has the practical effect of |
| 45 | * stopping tail-chasing closed loops when a feeder span is lost. |
| 46 | */ |
| 47 | #define DMSG_SPAN_MAXDIST 16 |
| 48 | |
| 49 | /* |
| 50 | * RED-BLACK TREE DEFINITIONS |
| 51 | * |
| 52 | * We need to track: |
| 53 | * |
| 54 | * (1) shared fsid's (a cluster). |
| 55 | * (2) unique fsid's (a node in a cluster) <--- LNK_SPAN transactions. |
| 56 | * |
| 57 | * We need to aggegate all active LNK_SPANs, aggregate, and create our own |
| 58 | * outgoing LNK_SPAN transactions on each of our connections representing |
| 59 | * the aggregated state. |
| 60 | * |
| 61 | * h2span_conn - list of iocom connections who wish to receive SPAN |
| 62 | * propagation from other connections. Might contain |
| 63 | * a filter string. Only iocom's with an open |
| 64 | * LNK_CONN transactions are applicable for SPAN |
| 65 | * propagation. |
| 66 | * |
| 67 | * h2span_relay - List of links relayed (via SPAN). Essentially |
| 68 | * each relay structure represents a LNK_SPAN |
| 69 | * transaction that we initiated, verses h2span_link |
| 70 | * which is a LNK_SPAN transaction that we received. |
| 71 | * |
| 72 | * -- |
| 73 | * |
| 74 | * h2span_cluster - Organizes the shared fsid's. One structure for |
| 75 | * each cluster. |
| 76 | * |
| 77 | * h2span_node - Organizes the nodes in a cluster. One structure |
| 78 | * for each unique {cluster,node}, aka {fsid, pfs_fsid}. |
| 79 | * |
| 80 | * h2span_link - Organizes all incoming and outgoing LNK_SPAN message |
| 81 | * transactions related to a node. |
| 82 | * |
| 83 | * One h2span_link structure for each incoming LNK_SPAN |
| 84 | * transaction. Links selected for propagation back |
| 85 | * out are also where the outgoing LNK_SPAN messages |
| 86 | * are indexed into (so we can propagate changes). |
| 87 | * |
| 88 | * The h2span_link's use a red-black tree to sort the |
| 89 | * distance hop metric for the incoming LNK_SPAN. We |
| 90 | * then select the top N for outgoing. When the |
| 91 | * topology changes the top N may also change and cause |
| 92 | * new outgoing LNK_SPAN transactions to be opened |
| 93 | * and less desireable ones to be closed, causing |
| 94 | * transactional aborts within the message flow in |
| 95 | * the process. |
| 96 | * |
| 97 | * Also note - All outgoing LNK_SPAN message transactions are also |
| 98 | * entered into a red-black tree for use by the routing |
| 99 | * function. This is handled by msg.c in the state |
| 100 | * code, not here. |
| 101 | */ |
| 102 | |
| 103 | struct h2span_link; |
| 104 | struct h2span_relay; |
| 105 | TAILQ_HEAD(h2span_media_queue, h2span_media); |
| 106 | TAILQ_HEAD(h2span_conn_queue, h2span_conn); |
| 107 | TAILQ_HEAD(h2span_relay_queue, h2span_relay); |
| 108 | |
| 109 | RB_HEAD(h2span_cluster_tree, h2span_cluster); |
| 110 | RB_HEAD(h2span_node_tree, h2span_node); |
| 111 | RB_HEAD(h2span_link_tree, h2span_link); |
| 112 | RB_HEAD(h2span_relay_tree, h2span_relay); |
| 113 | uint32_t DMsgRNSS; |
| 114 | |
| 115 | /* |
| 116 | * This represents a media |
| 117 | */ |
| 118 | struct h2span_media { |
| 119 | TAILQ_ENTRY(h2span_media) entry; |
| 120 | uuid_t mediaid; |
| 121 | int refs; |
| 122 | struct h2span_media_config { |
| 123 | dmsg_vol_data_t copy_run; |
| 124 | dmsg_vol_data_t copy_pend; |
| 125 | pthread_t thread; |
| 126 | pthread_cond_t cond; |
| 127 | int ctl; |
| 128 | int fd; |
| 129 | dmsg_iocom_t iocom; |
| 130 | pthread_t iocom_thread; |
| 131 | enum { H2MC_STOPPED, H2MC_CONNECT, H2MC_RUNNING } state; |
| 132 | } config[DMSG_COPYID_COUNT]; |
| 133 | }; |
| 134 | |
| 135 | typedef struct h2span_media_config h2span_media_config_t; |
| 136 | |
| 137 | #define H2CONFCTL_STOP 0x00000001 |
| 138 | #define H2CONFCTL_UPDATE 0x00000002 |
| 139 | |
| 140 | /* |
| 141 | * Received LNK_CONN transaction enables SPAN protocol over connection. |
| 142 | * (may contain filter). Typically one for each mount and several may |
| 143 | * share the same media. |
| 144 | */ |
| 145 | struct h2span_conn { |
| 146 | TAILQ_ENTRY(h2span_conn) entry; |
| 147 | struct h2span_relay_tree tree; |
| 148 | struct h2span_media *media; |
| 149 | dmsg_state_t *state; |
| 150 | }; |
| 151 | |
| 152 | /* |
| 153 | * All received LNK_SPANs are organized by cluster (pfs_clid), |
| 154 | * node (pfs_fsid), and link (received LNK_SPAN transaction). |
| 155 | */ |
| 156 | struct h2span_cluster { |
| 157 | RB_ENTRY(h2span_cluster) rbnode; |
| 158 | struct h2span_node_tree tree; |
| 159 | uuid_t pfs_clid; /* shared fsid */ |
| 160 | uint8_t peer_type; |
| 161 | char cl_label[128]; /* cluster label (typ PEER_BLOCK) */ |
| 162 | int refs; /* prevents destruction */ |
| 163 | }; |
| 164 | |
| 165 | struct h2span_node { |
| 166 | RB_ENTRY(h2span_node) rbnode; |
| 167 | struct h2span_link_tree tree; |
| 168 | struct h2span_cluster *cls; |
| 169 | uint8_t pfs_type; |
| 170 | uuid_t pfs_fsid; /* unique fsid */ |
| 171 | char fs_label[128]; /* fs label (typ PEER_HAMMER2) */ |
| 172 | void *opaque; |
| 173 | }; |
| 174 | |
| 175 | struct h2span_link { |
| 176 | RB_ENTRY(h2span_link) rbnode; |
| 177 | dmsg_state_t *state; /* state<->link */ |
| 178 | struct h2span_node *node; /* related node */ |
| 179 | uint32_t dist; |
| 180 | uint32_t rnss; |
| 181 | struct h2span_relay_queue relayq; /* relay out */ |
| 182 | }; |
| 183 | |
| 184 | /* |
| 185 | * Any LNK_SPAN transactions we receive which are relayed out other |
| 186 | * connections utilize this structure to track the LNK_SPAN transactions |
| 187 | * we initiate (relay out) on other connections. We only relay out |
| 188 | * LNK_SPANs on connections we have an open CONN transaction for. |
| 189 | * |
| 190 | * The relay structure points to the outgoing LNK_SPAN trans (out_state) |
| 191 | * and to the incoming LNK_SPAN transaction (in_state). The relay |
| 192 | * structure holds refs on the related states. |
| 193 | * |
| 194 | * In many respects this is the core of the protocol... actually figuring |
| 195 | * out what LNK_SPANs to relay. The spanid used for relaying is the |
| 196 | * address of the 'state' structure, which is why h2span_relay has to |
| 197 | * be entered into a RB-TREE based at h2span_conn (so we can look |
| 198 | * up the spanid to validate it). |
| 199 | */ |
| 200 | struct h2span_relay { |
| 201 | TAILQ_ENTRY(h2span_relay) entry; /* from link */ |
| 202 | RB_ENTRY(h2span_relay) rbnode; /* from h2span_conn */ |
| 203 | struct h2span_conn *conn; /* related CONN transaction */ |
| 204 | dmsg_state_t *source_rt; /* h2span_link state */ |
| 205 | dmsg_state_t *target_rt; /* h2span_relay state */ |
| 206 | }; |
| 207 | |
| 208 | typedef struct h2span_media h2span_media_t; |
| 209 | typedef struct h2span_conn h2span_conn_t; |
| 210 | typedef struct h2span_cluster h2span_cluster_t; |
| 211 | typedef struct h2span_node h2span_node_t; |
| 212 | typedef struct h2span_link h2span_link_t; |
| 213 | typedef struct h2span_relay h2span_relay_t; |
| 214 | |
| 215 | #define dmsg_termstr(array) _dmsg_termstr((array), sizeof(array)) |
| 216 | |
| 217 | static h2span_relay_t *dmsg_generate_relay(h2span_conn_t *conn, |
| 218 | h2span_link_t *slink); |
| 219 | static uint32_t dmsg_rnss(void); |
| 220 | |
| 221 | static __inline |
| 222 | void |
| 223 | _dmsg_termstr(char *base, size_t size) |
| 224 | { |
| 225 | base[size-1] = 0; |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | * Cluster peer_type, uuid, AND label must match for a match |
| 230 | */ |
| 231 | static |
| 232 | int |
| 233 | h2span_cluster_cmp(h2span_cluster_t *cls1, h2span_cluster_t *cls2) |
| 234 | { |
| 235 | int r; |
| 236 | |
| 237 | if (cls1->peer_type < cls2->peer_type) |
| 238 | return(-1); |
| 239 | if (cls1->peer_type > cls2->peer_type) |
| 240 | return(1); |
| 241 | r = uuid_compare(&cls1->pfs_clid, &cls2->pfs_clid, NULL); |
| 242 | if (r == 0) |
| 243 | r = strcmp(cls1->cl_label, cls2->cl_label); |
| 244 | |
| 245 | return r; |
| 246 | } |
| 247 | |
| 248 | /* |
| 249 | * Match against fs_label/pfs_fsid. Together these two items represent a |
| 250 | * unique node. In most cases the primary differentiator is pfs_fsid but |
| 251 | * we also string-match fs_label. |
| 252 | */ |
| 253 | static |
| 254 | int |
| 255 | h2span_node_cmp(h2span_node_t *node1, h2span_node_t *node2) |
| 256 | { |
| 257 | int r; |
| 258 | |
| 259 | r = strcmp(node1->fs_label, node2->fs_label); |
| 260 | if (r == 0) |
| 261 | r = uuid_compare(&node1->pfs_fsid, &node2->pfs_fsid, NULL); |
| 262 | return (r); |
| 263 | } |
| 264 | |
| 265 | /* |
| 266 | * Sort/subsort must match h2span_relay_cmp() under any given node |
| 267 | * to make the aggregation algorithm easier, so the best links are |
| 268 | * in the same sorted order as the best relays. |
| 269 | * |
| 270 | * NOTE: We cannot use link*->state->msgid because this msgid is created |
| 271 | * by each remote host and thus might wind up being the same. |
| 272 | */ |
| 273 | static |
| 274 | int |
| 275 | h2span_link_cmp(h2span_link_t *link1, h2span_link_t *link2) |
| 276 | { |
| 277 | if (link1->dist < link2->dist) |
| 278 | return(-1); |
| 279 | if (link1->dist > link2->dist) |
| 280 | return(1); |
| 281 | if (link1->rnss < link2->rnss) |
| 282 | return(-1); |
| 283 | if (link1->rnss > link2->rnss) |
| 284 | return(1); |
| 285 | #if 1 |
| 286 | if ((uintptr_t)link1->state < (uintptr_t)link2->state) |
| 287 | return(-1); |
| 288 | if ((uintptr_t)link1->state > (uintptr_t)link2->state) |
| 289 | return(1); |
| 290 | #else |
| 291 | if (link1->state->msgid < link2->state->msgid) |
| 292 | return(-1); |
| 293 | if (link1->state->msgid > link2->state->msgid) |
| 294 | return(1); |
| 295 | #endif |
| 296 | return(0); |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * Relay entries are sorted by node, subsorted by distance and link |
| 301 | * address (so we can match up the conn->tree relay topology with |
| 302 | * a node's link topology). |
| 303 | */ |
| 304 | static |
| 305 | int |
| 306 | h2span_relay_cmp(h2span_relay_t *relay1, h2span_relay_t *relay2) |
| 307 | { |
| 308 | h2span_link_t *link1 = relay1->source_rt->any.link; |
| 309 | h2span_link_t *link2 = relay2->source_rt->any.link; |
| 310 | |
| 311 | if ((intptr_t)link1->node < (intptr_t)link2->node) |
| 312 | return(-1); |
| 313 | if ((intptr_t)link1->node > (intptr_t)link2->node) |
| 314 | return(1); |
| 315 | if (link1->dist < link2->dist) |
| 316 | return(-1); |
| 317 | if (link1->dist > link2->dist) |
| 318 | return(1); |
| 319 | if (link1->rnss < link2->rnss) |
| 320 | return(-1); |
| 321 | if (link1->rnss > link2->rnss) |
| 322 | return(1); |
| 323 | #if 1 |
| 324 | if ((uintptr_t)link1->state < (uintptr_t)link2->state) |
| 325 | return(-1); |
| 326 | if ((uintptr_t)link1->state > (uintptr_t)link2->state) |
| 327 | return(1); |
| 328 | #else |
| 329 | if (link1->state->msgid < link2->state->msgid) |
| 330 | return(-1); |
| 331 | if (link1->state->msgid > link2->state->msgid) |
| 332 | return(1); |
| 333 | #endif |
| 334 | return(0); |
| 335 | } |
| 336 | |
| 337 | RB_PROTOTYPE_STATIC(h2span_cluster_tree, h2span_cluster, |
| 338 | rbnode, h2span_cluster_cmp); |
| 339 | RB_PROTOTYPE_STATIC(h2span_node_tree, h2span_node, |
| 340 | rbnode, h2span_node_cmp); |
| 341 | RB_PROTOTYPE_STATIC(h2span_link_tree, h2span_link, |
| 342 | rbnode, h2span_link_cmp); |
| 343 | RB_PROTOTYPE_STATIC(h2span_relay_tree, h2span_relay, |
| 344 | rbnode, h2span_relay_cmp); |
| 345 | |
| 346 | RB_GENERATE_STATIC(h2span_cluster_tree, h2span_cluster, |
| 347 | rbnode, h2span_cluster_cmp); |
| 348 | RB_GENERATE_STATIC(h2span_node_tree, h2span_node, |
| 349 | rbnode, h2span_node_cmp); |
| 350 | RB_GENERATE_STATIC(h2span_link_tree, h2span_link, |
| 351 | rbnode, h2span_link_cmp); |
| 352 | RB_GENERATE_STATIC(h2span_relay_tree, h2span_relay, |
| 353 | rbnode, h2span_relay_cmp); |
| 354 | |
| 355 | /* |
| 356 | * Global mutex protects cluster_tree lookups, connq, mediaq. |
| 357 | */ |
| 358 | static pthread_mutex_t cluster_mtx; |
| 359 | static struct h2span_cluster_tree cluster_tree = RB_INITIALIZER(cluster_tree); |
| 360 | static struct h2span_conn_queue connq = TAILQ_HEAD_INITIALIZER(connq); |
| 361 | static struct h2span_media_queue mediaq = TAILQ_HEAD_INITIALIZER(mediaq); |
| 362 | |
| 363 | static void dmsg_lnk_span(dmsg_msg_t *msg); |
| 364 | static void dmsg_lnk_conn(dmsg_msg_t *msg); |
| 365 | static void dmsg_lnk_circ(dmsg_msg_t *msg); |
| 366 | static void dmsg_lnk_relay(dmsg_msg_t *msg); |
| 367 | static void dmsg_relay_scan(h2span_conn_t *conn, h2span_node_t *node); |
| 368 | static void dmsg_relay_delete(h2span_relay_t *relay); |
| 369 | |
| 370 | static void *dmsg_volconf_thread(void *info); |
| 371 | static void dmsg_volconf_stop(h2span_media_config_t *conf); |
| 372 | static void dmsg_volconf_start(h2span_media_config_t *conf, |
| 373 | const char *hostname); |
| 374 | |
| 375 | void |
| 376 | dmsg_msg_lnk_signal(dmsg_iocom_t *iocom __unused) |
| 377 | { |
| 378 | pthread_mutex_lock(&cluster_mtx); |
| 379 | dmsg_relay_scan(NULL, NULL); |
| 380 | pthread_mutex_unlock(&cluster_mtx); |
| 381 | } |
| 382 | |
| 383 | /* |
| 384 | * DMSG_PROTO_LNK - Generic DMSG_PROTO_LNK. |
| 385 | * (incoming iocom lock not held) |
| 386 | * |
| 387 | * This function is typically called for one-way and opening-transactions |
| 388 | * since state->func is assigned after that, but it will also be called |
| 389 | * if no state->func is assigned on transaction-open. |
| 390 | */ |
| 391 | void |
| 392 | dmsg_msg_lnk(dmsg_msg_t *msg) |
| 393 | { |
| 394 | uint32_t icmd = msg->state ? msg->state->icmd : msg->any.head.cmd; |
| 395 | |
| 396 | switch(icmd & DMSGF_BASECMDMASK) { |
| 397 | case DMSG_LNK_CONN: |
| 398 | dmsg_lnk_conn(msg); |
| 399 | break; |
| 400 | case DMSG_LNK_SPAN: |
| 401 | dmsg_lnk_span(msg); |
| 402 | break; |
| 403 | case DMSG_LNK_CIRC: |
| 404 | dmsg_lnk_circ(msg); |
| 405 | break; |
| 406 | default: |
| 407 | fprintf(stderr, |
| 408 | "MSG_PROTO_LNK: Unknown msg %08x\n", msg->any.head.cmd); |
| 409 | dmsg_msg_reply(msg, DMSG_ERR_NOSUPP); |
| 410 | /* state invalid after reply */ |
| 411 | break; |
| 412 | } |
| 413 | } |
| 414 | |
| 415 | /* |
| 416 | * LNK_CONN - iocom identify message reception. |
| 417 | * (incoming iocom lock not held) |
| 418 | * |
| 419 | * Remote node identifies itself to us, sets up a SPAN filter, and gives us |
| 420 | * the ok to start transmitting SPANs. |
| 421 | */ |
| 422 | void |
| 423 | dmsg_lnk_conn(dmsg_msg_t *msg) |
| 424 | { |
| 425 | dmsg_state_t *state = msg->state; |
| 426 | h2span_media_t *media; |
| 427 | h2span_media_config_t *conf; |
| 428 | h2span_conn_t *conn; |
| 429 | h2span_relay_t *relay; |
| 430 | char *alloc = NULL; |
| 431 | int i; |
| 432 | |
| 433 | pthread_mutex_lock(&cluster_mtx); |
| 434 | |
| 435 | switch(msg->any.head.cmd & DMSGF_TRANSMASK) { |
| 436 | case DMSG_LNK_CONN | DMSGF_CREATE: |
| 437 | case DMSG_LNK_CONN | DMSGF_CREATE | DMSGF_DELETE: |
| 438 | /* |
| 439 | * On transaction start we allocate a new h2span_conn and |
| 440 | * acknowledge the request, leaving the transaction open. |
| 441 | * We then relay priority-selected SPANs. |
| 442 | */ |
| 443 | fprintf(stderr, "LNK_CONN(%08x): %s/%s/%s\n", |
| 444 | (uint32_t)msg->any.head.msgid, |
| 445 | dmsg_uuid_to_str(&msg->any.lnk_conn.pfs_clid, |
| 446 | &alloc), |
| 447 | msg->any.lnk_conn.cl_label, |
| 448 | msg->any.lnk_conn.fs_label); |
| 449 | free(alloc); |
| 450 | |
| 451 | conn = dmsg_alloc(sizeof(*conn)); |
| 452 | |
| 453 | RB_INIT(&conn->tree); |
| 454 | state->iocom->conn = conn; /* XXX only one */ |
| 455 | conn->state = state; |
| 456 | state->func = dmsg_lnk_conn; |
| 457 | state->any.conn = conn; |
| 458 | TAILQ_INSERT_TAIL(&connq, conn, entry); |
| 459 | |
| 460 | /* |
| 461 | * Set up media |
| 462 | */ |
| 463 | TAILQ_FOREACH(media, &mediaq, entry) { |
| 464 | if (uuid_compare(&msg->any.lnk_conn.mediaid, |
| 465 | &media->mediaid, NULL) == 0) { |
| 466 | break; |
| 467 | } |
| 468 | } |
| 469 | if (media == NULL) { |
| 470 | media = dmsg_alloc(sizeof(*media)); |
| 471 | media->mediaid = msg->any.lnk_conn.mediaid; |
| 472 | TAILQ_INSERT_TAIL(&mediaq, media, entry); |
| 473 | } |
| 474 | conn->media = media; |
| 475 | ++media->refs; |
| 476 | |
| 477 | if ((msg->any.head.cmd & DMSGF_DELETE) == 0) { |
| 478 | dmsg_msg_result(msg, 0); |
| 479 | dmsg_iocom_signal(msg->iocom); |
| 480 | break; |
| 481 | } |
| 482 | /* FALL THROUGH */ |
| 483 | case DMSG_LNK_CONN | DMSGF_DELETE: |
| 484 | case DMSG_LNK_ERROR | DMSGF_DELETE: |
| 485 | deleteconn: |
| 486 | /* |
| 487 | * On transaction terminate we clean out our h2span_conn |
| 488 | * and acknowledge the request, closing the transaction. |
| 489 | */ |
| 490 | fprintf(stderr, "LNK_CONN: Terminated\n"); |
| 491 | conn = state->any.conn; |
| 492 | assert(conn); |
| 493 | |
| 494 | /* |
| 495 | * Clean out the media structure. If refs drops to zero we |
| 496 | * also clean out the media config threads. These threads |
| 497 | * maintain span connections to other hammer2 service daemons. |
| 498 | */ |
| 499 | media = conn->media; |
| 500 | if (--media->refs == 0) { |
| 501 | fprintf(stderr, "Shutting down media spans\n"); |
| 502 | for (i = 0; i < DMSG_COPYID_COUNT; ++i) { |
| 503 | conf = &media->config[i]; |
| 504 | |
| 505 | if (conf->thread == NULL) |
| 506 | continue; |
| 507 | conf->ctl = H2CONFCTL_STOP; |
| 508 | pthread_cond_signal(&conf->cond); |
| 509 | } |
| 510 | for (i = 0; i < DMSG_COPYID_COUNT; ++i) { |
| 511 | conf = &media->config[i]; |
| 512 | |
| 513 | if (conf->thread == NULL) |
| 514 | continue; |
| 515 | pthread_mutex_unlock(&cluster_mtx); |
| 516 | pthread_join(conf->thread, NULL); |
| 517 | pthread_mutex_lock(&cluster_mtx); |
| 518 | conf->thread = NULL; |
| 519 | pthread_cond_destroy(&conf->cond); |
| 520 | } |
| 521 | fprintf(stderr, "Media shutdown complete\n"); |
| 522 | TAILQ_REMOVE(&mediaq, media, entry); |
| 523 | dmsg_free(media); |
| 524 | } |
| 525 | |
| 526 | /* |
| 527 | * Clean out all relays. This requires terminating each |
| 528 | * relay transaction. |
| 529 | */ |
| 530 | while ((relay = RB_ROOT(&conn->tree)) != NULL) { |
| 531 | dmsg_relay_delete(relay); |
| 532 | } |
| 533 | |
| 534 | /* |
| 535 | * Clean out conn |
| 536 | */ |
| 537 | conn->media = NULL; |
| 538 | conn->state = NULL; |
| 539 | msg->state->any.conn = NULL; |
| 540 | msg->state->iocom->conn = NULL; |
| 541 | TAILQ_REMOVE(&connq, conn, entry); |
| 542 | dmsg_free(conn); |
| 543 | |
| 544 | dmsg_msg_reply(msg, 0); |
| 545 | /* state invalid after reply */ |
| 546 | break; |
| 547 | case DMSG_LNK_VOLCONF: |
| 548 | /* |
| 549 | * One-way volume-configuration message is transmitted |
| 550 | * over the open LNK_CONN transaction. |
| 551 | */ |
| 552 | fprintf(stderr, "RECEIVED VOLCONF\n"); |
| 553 | if (msg->any.lnk_volconf.index < 0 || |
| 554 | msg->any.lnk_volconf.index >= DMSG_COPYID_COUNT) { |
| 555 | fprintf(stderr, "VOLCONF: ILLEGAL INDEX %d\n", |
| 556 | msg->any.lnk_volconf.index); |
| 557 | break; |
| 558 | } |
| 559 | if (msg->any.lnk_volconf.copy.path[sizeof(msg->any.lnk_volconf.copy.path) - 1] != 0 || |
| 560 | msg->any.lnk_volconf.copy.path[0] == 0) { |
| 561 | fprintf(stderr, "VOLCONF: ILLEGAL PATH %d\n", |
| 562 | msg->any.lnk_volconf.index); |
| 563 | break; |
| 564 | } |
| 565 | conn = msg->state->any.conn; |
| 566 | if (conn == NULL) { |
| 567 | fprintf(stderr, "VOLCONF: LNK_CONN is missing\n"); |
| 568 | break; |
| 569 | } |
| 570 | conf = &conn->media->config[msg->any.lnk_volconf.index]; |
| 571 | conf->copy_pend = msg->any.lnk_volconf.copy; |
| 572 | conf->ctl |= H2CONFCTL_UPDATE; |
| 573 | if (conf->thread == NULL) { |
| 574 | fprintf(stderr, "VOLCONF THREAD STARTED\n"); |
| 575 | pthread_cond_init(&conf->cond, NULL); |
| 576 | pthread_create(&conf->thread, NULL, |
| 577 | dmsg_volconf_thread, (void *)conf); |
| 578 | } |
| 579 | pthread_cond_signal(&conf->cond); |
| 580 | break; |
| 581 | default: |
| 582 | /* |
| 583 | * Failsafe |
| 584 | */ |
| 585 | if (msg->any.head.cmd & DMSGF_DELETE) |
| 586 | goto deleteconn; |
| 587 | dmsg_msg_reply(msg, DMSG_ERR_NOSUPP); |
| 588 | break; |
| 589 | } |
| 590 | pthread_mutex_unlock(&cluster_mtx); |
| 591 | } |
| 592 | |
| 593 | /* |
| 594 | * LNK_SPAN - Spanning tree protocol message reception |
| 595 | * (incoming iocom lock not held) |
| 596 | * |
| 597 | * Receive a spanning tree transactional message, creating or destroying |
| 598 | * a SPAN and propagating it to other iocoms. |
| 599 | */ |
| 600 | void |
| 601 | dmsg_lnk_span(dmsg_msg_t *msg) |
| 602 | { |
| 603 | dmsg_state_t *state = msg->state; |
| 604 | h2span_cluster_t dummy_cls; |
| 605 | h2span_node_t dummy_node; |
| 606 | h2span_cluster_t *cls; |
| 607 | h2span_node_t *node; |
| 608 | h2span_link_t *slink; |
| 609 | h2span_relay_t *relay; |
| 610 | char *alloc = NULL; |
| 611 | |
| 612 | assert((msg->any.head.cmd & DMSGF_REPLY) == 0); |
| 613 | |
| 614 | pthread_mutex_lock(&cluster_mtx); |
| 615 | |
| 616 | /* |
| 617 | * On transaction start we initialize the tracking infrastructure |
| 618 | */ |
| 619 | if (msg->any.head.cmd & DMSGF_CREATE) { |
| 620 | assert(state->func == NULL); |
| 621 | state->func = dmsg_lnk_span; |
| 622 | |
| 623 | dmsg_termstr(msg->any.lnk_span.cl_label); |
| 624 | dmsg_termstr(msg->any.lnk_span.fs_label); |
| 625 | |
| 626 | /* |
| 627 | * Find the cluster |
| 628 | */ |
| 629 | dummy_cls.pfs_clid = msg->any.lnk_span.pfs_clid; |
| 630 | dummy_cls.peer_type = msg->any.lnk_span.peer_type; |
| 631 | bcopy(msg->any.lnk_span.cl_label, |
| 632 | dummy_cls.cl_label, |
| 633 | sizeof(dummy_cls.cl_label)); |
| 634 | cls = RB_FIND(h2span_cluster_tree, &cluster_tree, &dummy_cls); |
| 635 | if (cls == NULL) { |
| 636 | cls = dmsg_alloc(sizeof(*cls)); |
| 637 | cls->pfs_clid = msg->any.lnk_span.pfs_clid; |
| 638 | cls->peer_type = msg->any.lnk_span.peer_type; |
| 639 | bcopy(msg->any.lnk_span.cl_label, |
| 640 | cls->cl_label, |
| 641 | sizeof(cls->cl_label)); |
| 642 | RB_INIT(&cls->tree); |
| 643 | RB_INSERT(h2span_cluster_tree, &cluster_tree, cls); |
| 644 | } |
| 645 | |
| 646 | /* |
| 647 | * Find the node |
| 648 | */ |
| 649 | dummy_node.pfs_fsid = msg->any.lnk_span.pfs_fsid; |
| 650 | bcopy(msg->any.lnk_span.fs_label, dummy_node.fs_label, |
| 651 | sizeof(dummy_node.fs_label)); |
| 652 | node = RB_FIND(h2span_node_tree, &cls->tree, &dummy_node); |
| 653 | if (node == NULL) { |
| 654 | node = dmsg_alloc(sizeof(*node)); |
| 655 | node->pfs_fsid = msg->any.lnk_span.pfs_fsid; |
| 656 | node->pfs_type = msg->any.lnk_span.pfs_type; |
| 657 | bcopy(msg->any.lnk_span.fs_label, |
| 658 | node->fs_label, |
| 659 | sizeof(node->fs_label)); |
| 660 | node->cls = cls; |
| 661 | RB_INIT(&node->tree); |
| 662 | RB_INSERT(h2span_node_tree, &cls->tree, node); |
| 663 | if (dmsg_node_handler) { |
| 664 | dmsg_node_handler(&node->opaque, msg, |
| 665 | DMSG_NODEOP_ADD); |
| 666 | } |
| 667 | } |
| 668 | |
| 669 | /* |
| 670 | * Create the link |
| 671 | */ |
| 672 | assert(state->any.link == NULL); |
| 673 | slink = dmsg_alloc(sizeof(*slink)); |
| 674 | TAILQ_INIT(&slink->relayq); |
| 675 | slink->node = node; |
| 676 | slink->dist = msg->any.lnk_span.dist; |
| 677 | slink->rnss = msg->any.lnk_span.rnss; |
| 678 | slink->state = state; |
| 679 | state->any.link = slink; |
| 680 | |
| 681 | RB_INSERT(h2span_link_tree, &node->tree, slink); |
| 682 | |
| 683 | fprintf(stderr, |
| 684 | "LNK_SPAN(thr %p): %p %s cl=%s fs=%s dist=%d\n", |
| 685 | msg->iocom, |
| 686 | slink, |
| 687 | dmsg_uuid_to_str(&msg->any.lnk_span.pfs_clid, &alloc), |
| 688 | msg->any.lnk_span.cl_label, |
| 689 | msg->any.lnk_span.fs_label, |
| 690 | msg->any.lnk_span.dist); |
| 691 | free(alloc); |
| 692 | #if 0 |
| 693 | dmsg_relay_scan(NULL, node); |
| 694 | #endif |
| 695 | dmsg_iocom_signal(msg->iocom); |
| 696 | } |
| 697 | |
| 698 | /* |
| 699 | * On transaction terminate we remove the tracking infrastructure. |
| 700 | */ |
| 701 | if (msg->any.head.cmd & DMSGF_DELETE) { |
| 702 | slink = state->any.link; |
| 703 | assert(slink != NULL); |
| 704 | node = slink->node; |
| 705 | cls = node->cls; |
| 706 | |
| 707 | fprintf(stderr, "LNK_DELE(thr %p): %p %s cl=%s fs=%s dist=%d\n", |
| 708 | msg->iocom, |
| 709 | slink, |
| 710 | dmsg_uuid_to_str(&cls->pfs_clid, &alloc), |
| 711 | state->msg->any.lnk_span.cl_label, |
| 712 | state->msg->any.lnk_span.fs_label, |
| 713 | state->msg->any.lnk_span.dist); |
| 714 | free(alloc); |
| 715 | |
| 716 | /* |
| 717 | * Clean out all relays. This requires terminating each |
| 718 | * relay transaction. |
| 719 | */ |
| 720 | while ((relay = TAILQ_FIRST(&slink->relayq)) != NULL) { |
| 721 | dmsg_relay_delete(relay); |
| 722 | } |
| 723 | |
| 724 | /* |
| 725 | * Clean out the topology |
| 726 | */ |
| 727 | RB_REMOVE(h2span_link_tree, &node->tree, slink); |
| 728 | if (RB_EMPTY(&node->tree)) { |
| 729 | RB_REMOVE(h2span_node_tree, &cls->tree, node); |
| 730 | if (dmsg_node_handler) { |
| 731 | dmsg_node_handler(&node->opaque, msg, |
| 732 | DMSG_NODEOP_DEL); |
| 733 | } |
| 734 | if (RB_EMPTY(&cls->tree) && cls->refs == 0) { |
| 735 | RB_REMOVE(h2span_cluster_tree, |
| 736 | &cluster_tree, cls); |
| 737 | dmsg_free(cls); |
| 738 | } |
| 739 | node->cls = NULL; |
| 740 | dmsg_free(node); |
| 741 | node = NULL; |
| 742 | } |
| 743 | state->any.link = NULL; |
| 744 | slink->state = NULL; |
| 745 | slink->node = NULL; |
| 746 | dmsg_free(slink); |
| 747 | |
| 748 | /* |
| 749 | * We have to terminate the transaction |
| 750 | */ |
| 751 | dmsg_state_reply(state, 0); |
| 752 | /* state invalid after reply */ |
| 753 | |
| 754 | /* |
| 755 | * If the node still exists issue any required updates. If |
| 756 | * it doesn't then all related relays have already been |
| 757 | * removed and there's nothing left to do. |
| 758 | */ |
| 759 | #if 0 |
| 760 | if (node) |
| 761 | dmsg_relay_scan(NULL, node); |
| 762 | #endif |
| 763 | if (node) |
| 764 | dmsg_iocom_signal(msg->iocom); |
| 765 | } |
| 766 | |
| 767 | pthread_mutex_unlock(&cluster_mtx); |
| 768 | } |
| 769 | |
| 770 | /* |
| 771 | * LNK_CIRC - Virtual circuit protocol message reception |
| 772 | * (incoming iocom lock not held) |
| 773 | * |
| 774 | * Handles all cases. |
| 775 | */ |
| 776 | void |
| 777 | dmsg_lnk_circ(dmsg_msg_t *msg) |
| 778 | { |
| 779 | dmsg_circuit_t *circA; |
| 780 | dmsg_circuit_t *circB; |
| 781 | dmsg_state_t *rx_state; |
| 782 | dmsg_state_t *tx_state; |
| 783 | dmsg_state_t *state; |
| 784 | dmsg_state_t dummy; |
| 785 | dmsg_msg_t *fwd_msg; |
| 786 | dmsg_iocom_t *iocomA; |
| 787 | dmsg_iocom_t *iocomB; |
| 788 | |
| 789 | /*pthread_mutex_lock(&cluster_mtx);*/ |
| 790 | |
| 791 | switch (msg->any.head.cmd & (DMSGF_CREATE | |
| 792 | DMSGF_DELETE | |
| 793 | DMSGF_REPLY)) { |
| 794 | case DMSGF_CREATE: |
| 795 | case DMSGF_CREATE | DMSGF_DELETE: |
| 796 | /* |
| 797 | * (A) wishes to establish a virtual circuit through us to (B). |
| 798 | * (B) is specified by lnk_circ.target (the message id for |
| 799 | * a LNK_SPAN that (A) received from us which represents (B)). |
| 800 | * |
| 801 | * Designate the originator of the circuit (the current |
| 802 | * remote end) as (A) and the other side as (B). |
| 803 | * |
| 804 | * Accept the VC but do not reply. We will wait for the end- |
| 805 | * to-end reply to propagate back. |
| 806 | */ |
| 807 | iocomA = msg->iocom; |
| 808 | |
| 809 | /* |
| 810 | * Locate the open transaction state that the other end |
| 811 | * specified in <target>. This will be an open SPAN |
| 812 | * transaction that we transmitted (h2span_relay) over |
| 813 | * the interface the LNK_CIRC is being received on. |
| 814 | * |
| 815 | * (all LNK_CIRC's that we transmit are on circuit0) |
| 816 | */ |
| 817 | pthread_mutex_lock(&iocomA->mtx); |
| 818 | dummy.msgid = msg->any.lnk_circ.target; |
| 819 | tx_state = RB_FIND(dmsg_state_tree, |
| 820 | &iocomA->circuit0.statewr_tree, |
| 821 | &dummy); |
| 822 | /* XXX state refs */ |
| 823 | assert(tx_state); |
| 824 | pthread_mutex_unlock(&iocomA->mtx); |
| 825 | |
| 826 | /* locate h2span_link */ |
| 827 | rx_state = tx_state->any.relay->source_rt; |
| 828 | |
| 829 | /* |
| 830 | * A wishes to establish a VC through us to the |
| 831 | * specified target. |
| 832 | * |
| 833 | * A sends us the msgid of an open SPAN transaction |
| 834 | * it received from us as <target>. |
| 835 | */ |
| 836 | circA = dmsg_alloc(sizeof(*circA)); |
| 837 | circA->iocom = iocomA; |
| 838 | circA->state = msg->state; /* LNK_CIRC state */ |
| 839 | circA->msgid = msg->state->msgid; |
| 840 | circA->span_state = tx_state; /* H2SPAN_RELAY state */ |
| 841 | circA->is_relay = 1; |
| 842 | circA->refs = 2; /* state and peer */ |
| 843 | msg->state->any.circ = circA; |
| 844 | |
| 845 | iocomB = rx_state->iocom; |
| 846 | |
| 847 | circB = dmsg_alloc(sizeof(*circB)); |
| 848 | |
| 849 | /* |
| 850 | * Create a LNK_CIRC transaction on B |
| 851 | */ |
| 852 | fwd_msg = dmsg_msg_alloc(&iocomB->circuit0, |
| 853 | 0, DMSG_LNK_CIRC | DMSGF_CREATE, |
| 854 | dmsg_lnk_circ, circB); |
| 855 | fwd_msg->state->any.circ = circB; |
| 856 | circB->iocom = iocomB; |
| 857 | circB->state = fwd_msg->state; /* LNK_CIRC state */ |
| 858 | circB->msgid = fwd_msg->any.head.msgid; |
| 859 | circB->span_state = rx_state; /* H2SPAN_LINK state */ |
| 860 | circB->is_relay = 0; |
| 861 | circB->refs = 2; /* state and peer */ |
| 862 | |
| 863 | /* |
| 864 | * Link the two circuits together. |
| 865 | */ |
| 866 | circA->peer = circB; |
| 867 | circB->peer = circA; |
| 868 | |
| 869 | if (RB_INSERT(dmsg_circuit_tree, &iocomA->circuit_tree, circA)) |
| 870 | assert(0); |
| 871 | if (RB_INSERT(dmsg_circuit_tree, &iocomB->circuit_tree, circB)) |
| 872 | assert(0); |
| 873 | |
| 874 | dmsg_msg_write(fwd_msg); |
| 875 | |
| 876 | if ((msg->any.head.cmd & DMSGF_DELETE) == 0) |
| 877 | break; |
| 878 | /* FALL THROUGH TO DELETE */ |
| 879 | case DMSGF_DELETE: |
| 880 | /* |
| 881 | * (A) Is deleting the virtual circuit, propogate closure |
| 882 | * to (B). |
| 883 | */ |
| 884 | iocomA = msg->iocom; |
| 885 | circA = msg->state->any.circ; |
| 886 | circB = circA->peer; |
| 887 | assert(msg->state == circA->state); |
| 888 | |
| 889 | /* |
| 890 | * If we are closing A and the peer B is closed, disconnect. |
| 891 | */ |
| 892 | if (circB && (state = circB->state) != NULL) { |
| 893 | if (state->rxcmd & DMSGF_DELETE) { |
| 894 | circB->state = NULL; |
| 895 | state->any.circ = NULL; |
| 896 | dmsg_circuit_drop(circB); |
| 897 | } |
| 898 | dmsg_state_reply(state, msg->any.head.error); |
| 899 | } |
| 900 | |
| 901 | /* |
| 902 | * If both sides now closed terminate the peer association |
| 903 | * and the state association. This may drop up to two refs |
| 904 | * on circA and one on circB. |
| 905 | */ |
| 906 | if (circA->state->txcmd & DMSGF_DELETE) { |
| 907 | if (circB) { |
| 908 | circA->peer = NULL; |
| 909 | circB->peer = NULL; |
| 910 | dmsg_circuit_drop(circA); |
| 911 | dmsg_circuit_drop(circB); /* XXX SMP */ |
| 912 | } |
| 913 | circA->state->any.circ = NULL; |
| 914 | circA->state = NULL; |
| 915 | dmsg_circuit_drop(circA); |
| 916 | } |
| 917 | break; |
| 918 | case DMSGF_REPLY | DMSGF_CREATE: |
| 919 | case DMSGF_REPLY | DMSGF_CREATE | DMSGF_DELETE: |
| 920 | /* |
| 921 | * (B) is acknowledging the creation of the virtual |
| 922 | * circuit. This propagates all the way back to (A), though |
| 923 | * it should be noted that (A) can start issuing commands |
| 924 | * via the virtual circuit before seeing this reply. |
| 925 | */ |
| 926 | circB = msg->state->any.circ; |
| 927 | circA = circB->peer; |
| 928 | assert(msg->state == circB->state); |
| 929 | if (circA && (msg->any.head.cmd & DMSGF_DELETE) == 0) { |
| 930 | dmsg_state_result(circA->state, msg->any.head.error); |
| 931 | break; |
| 932 | } |
| 933 | /* FALL THROUGH TO DELETE */ |
| 934 | case DMSGF_REPLY | DMSGF_DELETE: |
| 935 | /* |
| 936 | * (B) Is deleting the virtual circuit or acknowledging |
| 937 | * our deletion of the virtual circuit, propogate closure |
| 938 | * to (A). |
| 939 | */ |
| 940 | iocomB = msg->iocom; |
| 941 | circB = msg->state->any.circ; |
| 942 | circA = circB->peer; |
| 943 | assert(msg->state == circB->state); |
| 944 | |
| 945 | /* |
| 946 | * If we are closing A and the peer B is closed, disconnect. |
| 947 | */ |
| 948 | if (circA && (state = circA->state) != NULL) { |
| 949 | if (state->rxcmd & DMSGF_DELETE) { |
| 950 | circA->state = NULL; |
| 951 | state->any.circ = NULL; |
| 952 | dmsg_circuit_drop(circA); |
| 953 | } |
| 954 | dmsg_state_reply(state, msg->any.head.error); |
| 955 | } |
| 956 | |
| 957 | /* |
| 958 | * If both sides now closed terminate the peer association |
| 959 | * and the state association. This may drop up to two refs |
| 960 | * on circA and one on circB. |
| 961 | */ |
| 962 | if (circB->state->txcmd & DMSGF_DELETE) { |
| 963 | if (circA) { |
| 964 | circB->peer = NULL; |
| 965 | circA->peer = NULL; |
| 966 | dmsg_circuit_drop(circB); |
| 967 | dmsg_circuit_drop(circA); /* XXX SMP */ |
| 968 | } |
| 969 | circB->state->any.circ = NULL; |
| 970 | circB->state = NULL; |
| 971 | dmsg_circuit_drop(circB); |
| 972 | } |
| 973 | break; |
| 974 | } |
| 975 | |
| 976 | /*pthread_mutex_lock(&cluster_mtx);*/ |
| 977 | } |
| 978 | |
| 979 | /* |
| 980 | * Update relay transactions for SPANs. |
| 981 | * |
| 982 | * Called with cluster_mtx held. |
| 983 | */ |
| 984 | static void dmsg_relay_scan_specific(h2span_node_t *node, |
| 985 | h2span_conn_t *conn); |
| 986 | |
| 987 | static void |
| 988 | dmsg_relay_scan(h2span_conn_t *conn, h2span_node_t *node) |
| 989 | { |
| 990 | h2span_cluster_t *cls; |
| 991 | |
| 992 | if (node) { |
| 993 | /* |
| 994 | * Iterate specific node |
| 995 | */ |
| 996 | TAILQ_FOREACH(conn, &connq, entry) |
| 997 | dmsg_relay_scan_specific(node, conn); |
| 998 | } else { |
| 999 | /* |
| 1000 | * Full iteration. |
| 1001 | * |
| 1002 | * Iterate cluster ids, nodes, and either a specific connection |
| 1003 | * or all connections. |
| 1004 | */ |
| 1005 | RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) { |
| 1006 | /* |
| 1007 | * Iterate node ids |
| 1008 | */ |
| 1009 | RB_FOREACH(node, h2span_node_tree, &cls->tree) { |
| 1010 | /* |
| 1011 | * Synchronize the node's link (received SPANs) |
| 1012 | * with each connection's relays. |
| 1013 | */ |
| 1014 | if (conn) { |
| 1015 | dmsg_relay_scan_specific(node, conn); |
| 1016 | } else { |
| 1017 | TAILQ_FOREACH(conn, &connq, entry) { |
| 1018 | dmsg_relay_scan_specific(node, |
| 1019 | conn); |
| 1020 | } |
| 1021 | assert(conn == NULL); |
| 1022 | } |
| 1023 | } |
| 1024 | } |
| 1025 | } |
| 1026 | } |
| 1027 | |
| 1028 | /* |
| 1029 | * Update the relay'd SPANs for this (node, conn). |
| 1030 | * |
| 1031 | * Iterate links and adjust relays to match. We only propagate the top link |
| 1032 | * for now (XXX we want to propagate the top two). |
| 1033 | * |
| 1034 | * The dmsg_relay_scan_cmp() function locates the first relay element |
| 1035 | * for any given node. The relay elements will be sub-sorted by dist. |
| 1036 | */ |
| 1037 | struct relay_scan_info { |
| 1038 | h2span_node_t *node; |
| 1039 | h2span_relay_t *relay; |
| 1040 | }; |
| 1041 | |
| 1042 | static int |
| 1043 | dmsg_relay_scan_cmp(h2span_relay_t *relay, void *arg) |
| 1044 | { |
| 1045 | struct relay_scan_info *info = arg; |
| 1046 | |
| 1047 | if ((intptr_t)relay->source_rt->any.link->node < (intptr_t)info->node) |
| 1048 | return(-1); |
| 1049 | if ((intptr_t)relay->source_rt->any.link->node > (intptr_t)info->node) |
| 1050 | return(1); |
| 1051 | return(0); |
| 1052 | } |
| 1053 | |
| 1054 | static int |
| 1055 | dmsg_relay_scan_callback(h2span_relay_t *relay, void *arg) |
| 1056 | { |
| 1057 | struct relay_scan_info *info = arg; |
| 1058 | |
| 1059 | info->relay = relay; |
| 1060 | return(-1); |
| 1061 | } |
| 1062 | |
| 1063 | static void |
| 1064 | dmsg_relay_scan_specific(h2span_node_t *node, h2span_conn_t *conn) |
| 1065 | { |
| 1066 | struct relay_scan_info info; |
| 1067 | h2span_relay_t *relay; |
| 1068 | h2span_relay_t *next_relay; |
| 1069 | h2span_link_t *slink; |
| 1070 | dmsg_lnk_conn_t *lconn; |
| 1071 | dmsg_lnk_span_t *lspan; |
| 1072 | int count; |
| 1073 | int maxcount = 2; |
| 1074 | uint32_t lastdist = DMSG_SPAN_MAXDIST; |
| 1075 | uint32_t lastrnss = 0; |
| 1076 | |
| 1077 | info.node = node; |
| 1078 | info.relay = NULL; |
| 1079 | |
| 1080 | /* |
| 1081 | * Locate the first related relay for the node on this connection. |
| 1082 | * relay will be NULL if there were none. |
| 1083 | */ |
| 1084 | RB_SCAN(h2span_relay_tree, &conn->tree, |
| 1085 | dmsg_relay_scan_cmp, dmsg_relay_scan_callback, &info); |
| 1086 | relay = info.relay; |
| 1087 | info.relay = NULL; |
| 1088 | if (relay) |
| 1089 | assert(relay->source_rt->any.link->node == node); |
| 1090 | |
| 1091 | if (DMsgDebugOpt > 8) |
| 1092 | fprintf(stderr, "relay scan for connection %p\n", conn); |
| 1093 | |
| 1094 | /* |
| 1095 | * Iterate the node's links (received SPANs) in distance order, |
| 1096 | * lowest (best) dist first. |
| 1097 | * |
| 1098 | * PROPAGATE THE BEST LINKS OVER THE SPECIFIED CONNECTION. |
| 1099 | * |
| 1100 | * Track relays while iterating the best links and construct |
| 1101 | * missing relays when necessary. |
| 1102 | * |
| 1103 | * (If some prior better link was removed it would have also |
| 1104 | * removed the relay, so the relay can only match exactly or |
| 1105 | * be worse). |
| 1106 | */ |
| 1107 | count = 0; |
| 1108 | RB_FOREACH(slink, h2span_link_tree, &node->tree) { |
| 1109 | /* |
| 1110 | * Increment count of successful relays. This isn't |
| 1111 | * quite accurate if we break out but nothing after |
| 1112 | * the loop uses (count). |
| 1113 | * |
| 1114 | * If count exceeds the maximum number of relays we desire |
| 1115 | * we normally want to break out. However, in order to |
| 1116 | * guarantee a symmetric path we have to continue if both |
| 1117 | * (dist) and (rnss) continue to match. Otherwise the SPAN |
| 1118 | * propagation in the reverse direction may choose different |
| 1119 | * routes and we will not have a symmetric path. |
| 1120 | * |
| 1121 | * NOTE: Spanning tree does not have to be symmetrical so |
| 1122 | * this code is not currently enabled. |
| 1123 | */ |
| 1124 | if (++count >= maxcount) { |
| 1125 | #ifdef REQUIRE_SYMMETRICAL |
| 1126 | if (lastdist != slink->dist || lastrnss != slink->rnss) |
| 1127 | break; |
| 1128 | #else |
| 1129 | break; |
| 1130 | #endif |
| 1131 | /* go beyond the nominal maximum desired relays */ |
| 1132 | } |
| 1133 | |
| 1134 | /* |
| 1135 | * Match, relay already in-place, get the next |
| 1136 | * relay to match against the next slink. |
| 1137 | */ |
| 1138 | if (relay && relay->source_rt->any.link == slink) { |
| 1139 | relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay); |
| 1140 | continue; |
| 1141 | } |
| 1142 | |
| 1143 | /* |
| 1144 | * We might want this SLINK, if it passes our filters. |
| 1145 | * |
| 1146 | * The spanning tree can cause closed loops so we have |
| 1147 | * to limit slink->dist. |
| 1148 | */ |
| 1149 | if (slink->dist > DMSG_SPAN_MAXDIST) |
| 1150 | break; |
| 1151 | |
| 1152 | /* |
| 1153 | * Don't bother transmitting a LNK_SPAN out the same |
| 1154 | * connection it came in on. Trivial optimization. |
| 1155 | */ |
| 1156 | if (slink->state->iocom == conn->state->iocom) |
| 1157 | break; |
| 1158 | |
| 1159 | /* |
| 1160 | * NOTE ON FILTERS: The protocol spec allows non-requested |
| 1161 | * SPANs to be transmitted, the other end is expected to |
| 1162 | * leave their transactions open but otherwise ignore them. |
| 1163 | * |
| 1164 | * Don't bother transmitting if the remote connection |
| 1165 | * is not accepting this SPAN's peer_type. |
| 1166 | * |
| 1167 | * pfs_mask is typically used so pure clients can filter |
| 1168 | * out receiving SPANs for other pure clients. |
| 1169 | */ |
| 1170 | lspan = &slink->state->msg->any.lnk_span; |
| 1171 | lconn = &conn->state->msg->any.lnk_conn; |
| 1172 | if (((1LLU << lspan->peer_type) & lconn->peer_mask) == 0) |
| 1173 | break; |
| 1174 | if (((1LLU << lspan->pfs_type) & lconn->pfs_mask) == 0) |
| 1175 | break; |
| 1176 | |
| 1177 | /* |
| 1178 | * Do not give pure clients visibility to other pure clients |
| 1179 | */ |
| 1180 | if (lconn->pfs_type == DMSG_PFSTYPE_CLIENT && |
| 1181 | lspan->pfs_type == DMSG_PFSTYPE_CLIENT) { |
| 1182 | break; |
| 1183 | } |
| 1184 | |
| 1185 | /* |
| 1186 | * Connection filter, if cluster uuid is not NULL it must |
| 1187 | * match the span cluster uuid. Only applies when the |
| 1188 | * peer_type matches. |
| 1189 | */ |
| 1190 | if (lspan->peer_type == lconn->peer_type && |
| 1191 | !uuid_is_nil(&lconn->pfs_clid, NULL) && |
| 1192 | uuid_compare(&slink->node->cls->pfs_clid, |
| 1193 | &lconn->pfs_clid, NULL)) { |
| 1194 | break; |
| 1195 | } |
| 1196 | |
| 1197 | /* |
| 1198 | * Connection filter, if cluster label is not empty it must |
| 1199 | * match the span cluster label. Only applies when the |
| 1200 | * peer_type matches. |
| 1201 | */ |
| 1202 | if (lspan->peer_type == lconn->peer_type && |
| 1203 | lconn->cl_label[0] && |
| 1204 | strcmp(lconn->cl_label, slink->node->cls->cl_label)) { |
| 1205 | break; |
| 1206 | } |
| 1207 | |
| 1208 | /* |
| 1209 | * NOTE! pfs_fsid differentiates nodes within the same cluster |
| 1210 | * so we obviously don't want to match those. Similarly |
| 1211 | * for fs_label. |
| 1212 | */ |
| 1213 | |
| 1214 | /* |
| 1215 | * Ok, we've accepted this SPAN for relaying. |
| 1216 | */ |
| 1217 | assert(relay == NULL || |
| 1218 | relay->source_rt->any.link->node != slink->node || |
| 1219 | relay->source_rt->any.link->dist >= slink->dist); |
| 1220 | relay = dmsg_generate_relay(conn, slink); |
| 1221 | lastdist = slink->dist; |
| 1222 | lastrnss = slink->rnss; |
| 1223 | |
| 1224 | /* |
| 1225 | * Match (created new relay), get the next relay to |
| 1226 | * match against the next slink. |
| 1227 | */ |
| 1228 | relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay); |
| 1229 | } |
| 1230 | |
| 1231 | /* |
| 1232 | * Any remaining relay's belonging to this connection which match |
| 1233 | * the node are in excess of the current aggregate spanning state |
| 1234 | * and should be removed. |
| 1235 | */ |
| 1236 | while (relay && relay->source_rt->any.link->node == node) { |
| 1237 | next_relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay); |
| 1238 | dmsg_relay_delete(relay); |
| 1239 | relay = next_relay; |
| 1240 | } |
| 1241 | } |
| 1242 | |
| 1243 | /* |
| 1244 | * Helper function to generate missing relay. |
| 1245 | * |
| 1246 | * cluster_mtx must be held |
| 1247 | */ |
| 1248 | static |
| 1249 | h2span_relay_t * |
| 1250 | dmsg_generate_relay(h2span_conn_t *conn, h2span_link_t *slink) |
| 1251 | { |
| 1252 | h2span_relay_t *relay; |
| 1253 | h2span_node_t *node; |
| 1254 | dmsg_msg_t *msg; |
| 1255 | |
| 1256 | node = slink->node; |
| 1257 | |
| 1258 | relay = dmsg_alloc(sizeof(*relay)); |
| 1259 | relay->conn = conn; |
| 1260 | relay->source_rt = slink->state; |
| 1261 | /* relay->source_rt->any.link = slink; */ |
| 1262 | |
| 1263 | /* |
| 1264 | * NOTE: relay->target_rt->any.relay set to relay by alloc. |
| 1265 | */ |
| 1266 | msg = dmsg_msg_alloc(&conn->state->iocom->circuit0, |
| 1267 | 0, DMSG_LNK_SPAN | DMSGF_CREATE, |
| 1268 | dmsg_lnk_relay, relay); |
| 1269 | relay->target_rt = msg->state; |
| 1270 | |
| 1271 | msg->any.lnk_span = slink->state->msg->any.lnk_span; |
| 1272 | msg->any.lnk_span.dist = slink->dist + 1; |
| 1273 | msg->any.lnk_span.rnss = slink->rnss + dmsg_rnss(); |
| 1274 | |
| 1275 | RB_INSERT(h2span_relay_tree, &conn->tree, relay); |
| 1276 | TAILQ_INSERT_TAIL(&slink->relayq, relay, entry); |
| 1277 | |
| 1278 | dmsg_msg_write(msg); |
| 1279 | |
| 1280 | return (relay); |
| 1281 | } |
| 1282 | |
| 1283 | /* |
| 1284 | * Messages received on relay SPANs. These are open transactions so it is |
| 1285 | * in fact possible for the other end to close the transaction. |
| 1286 | * |
| 1287 | * XXX MPRACE on state structure |
| 1288 | */ |
| 1289 | static void |
| 1290 | dmsg_lnk_relay(dmsg_msg_t *msg) |
| 1291 | { |
| 1292 | dmsg_state_t *state = msg->state; |
| 1293 | h2span_relay_t *relay; |
| 1294 | |
| 1295 | assert(msg->any.head.cmd & DMSGF_REPLY); |
| 1296 | |
| 1297 | if (msg->any.head.cmd & DMSGF_DELETE) { |
| 1298 | pthread_mutex_lock(&cluster_mtx); |
| 1299 | if ((relay = state->any.relay) != NULL) { |
| 1300 | dmsg_relay_delete(relay); |
| 1301 | } else { |
| 1302 | dmsg_state_reply(state, 0); |
| 1303 | } |
| 1304 | pthread_mutex_unlock(&cluster_mtx); |
| 1305 | } |
| 1306 | } |
| 1307 | |
| 1308 | |
| 1309 | static |
| 1310 | void |
| 1311 | dmsg_relay_delete(h2span_relay_t *relay) |
| 1312 | { |
| 1313 | fprintf(stderr, |
| 1314 | "RELAY DELETE %p RELAY %p ON CLS=%p NODE=%p DIST=%d FD %d STATE %p\n", |
| 1315 | relay->source_rt->any.link, |
| 1316 | relay, |
| 1317 | relay->source_rt->any.link->node->cls, relay->source_rt->any.link->node, |
| 1318 | relay->source_rt->any.link->dist, |
| 1319 | relay->conn->state->iocom->sock_fd, relay->target_rt); |
| 1320 | |
| 1321 | RB_REMOVE(h2span_relay_tree, &relay->conn->tree, relay); |
| 1322 | TAILQ_REMOVE(&relay->source_rt->any.link->relayq, relay, entry); |
| 1323 | |
| 1324 | if (relay->target_rt) { |
| 1325 | relay->target_rt->any.relay = NULL; |
| 1326 | dmsg_state_reply(relay->target_rt, 0); |
| 1327 | /* state invalid after reply */ |
| 1328 | relay->target_rt = NULL; |
| 1329 | } |
| 1330 | relay->conn = NULL; |
| 1331 | relay->source_rt = NULL; |
| 1332 | dmsg_free(relay); |
| 1333 | } |
| 1334 | |
| 1335 | static void * |
| 1336 | dmsg_volconf_thread(void *info) |
| 1337 | { |
| 1338 | h2span_media_config_t *conf = info; |
| 1339 | |
| 1340 | pthread_mutex_lock(&cluster_mtx); |
| 1341 | while ((conf->ctl & H2CONFCTL_STOP) == 0) { |
| 1342 | if (conf->ctl & H2CONFCTL_UPDATE) { |
| 1343 | fprintf(stderr, "VOLCONF UPDATE\n"); |
| 1344 | conf->ctl &= ~H2CONFCTL_UPDATE; |
| 1345 | if (bcmp(&conf->copy_run, &conf->copy_pend, |
| 1346 | sizeof(conf->copy_run)) == 0) { |
| 1347 | fprintf(stderr, "VOLCONF: no changes\n"); |
| 1348 | continue; |
| 1349 | } |
| 1350 | /* |
| 1351 | * XXX TODO - auto reconnect on lookup failure or |
| 1352 | * connect failure or stream failure. |
| 1353 | */ |
| 1354 | |
| 1355 | pthread_mutex_unlock(&cluster_mtx); |
| 1356 | dmsg_volconf_stop(conf); |
| 1357 | conf->copy_run = conf->copy_pend; |
| 1358 | if (conf->copy_run.copyid != 0 && |
| 1359 | strncmp(conf->copy_run.path, "span:", 5) == 0) { |
| 1360 | dmsg_volconf_start(conf, |
| 1361 | conf->copy_run.path + 5); |
| 1362 | } |
| 1363 | pthread_mutex_lock(&cluster_mtx); |
| 1364 | fprintf(stderr, "VOLCONF UPDATE DONE state %d\n", conf->state); |
| 1365 | } |
| 1366 | if (conf->state == H2MC_CONNECT) { |
| 1367 | dmsg_volconf_start(conf, conf->copy_run.path + 5); |
| 1368 | pthread_mutex_unlock(&cluster_mtx); |
| 1369 | sleep(5); |
| 1370 | pthread_mutex_lock(&cluster_mtx); |
| 1371 | } else { |
| 1372 | pthread_cond_wait(&conf->cond, &cluster_mtx); |
| 1373 | } |
| 1374 | } |
| 1375 | pthread_mutex_unlock(&cluster_mtx); |
| 1376 | dmsg_volconf_stop(conf); |
| 1377 | return(NULL); |
| 1378 | } |
| 1379 | |
| 1380 | static |
| 1381 | void |
| 1382 | dmsg_volconf_stop(h2span_media_config_t *conf) |
| 1383 | { |
| 1384 | switch(conf->state) { |
| 1385 | case H2MC_STOPPED: |
| 1386 | break; |
| 1387 | case H2MC_CONNECT: |
| 1388 | conf->state = H2MC_STOPPED; |
| 1389 | break; |
| 1390 | case H2MC_RUNNING: |
| 1391 | shutdown(conf->fd, SHUT_WR); |
| 1392 | pthread_join(conf->iocom_thread, NULL); |
| 1393 | conf->iocom_thread = NULL; |
| 1394 | break; |
| 1395 | } |
| 1396 | } |
| 1397 | |
| 1398 | static |
| 1399 | void |
| 1400 | dmsg_volconf_start(h2span_media_config_t *conf, const char *hostname) |
| 1401 | { |
| 1402 | dmsg_master_service_info_t *info; |
| 1403 | |
| 1404 | switch(conf->state) { |
| 1405 | case H2MC_STOPPED: |
| 1406 | case H2MC_CONNECT: |
| 1407 | conf->fd = dmsg_connect(hostname); |
| 1408 | if (conf->fd < 0) { |
| 1409 | fprintf(stderr, "Unable to connect to %s\n", hostname); |
| 1410 | conf->state = H2MC_CONNECT; |
| 1411 | } else { |
| 1412 | info = malloc(sizeof(*info)); |
| 1413 | bzero(info, sizeof(*info)); |
| 1414 | info->fd = conf->fd; |
| 1415 | info->detachme = 0; |
| 1416 | conf->state = H2MC_RUNNING; |
| 1417 | pthread_create(&conf->iocom_thread, NULL, |
| 1418 | dmsg_master_service, info); |
| 1419 | } |
| 1420 | break; |
| 1421 | case H2MC_RUNNING: |
| 1422 | break; |
| 1423 | } |
| 1424 | } |
| 1425 | |
| 1426 | /************************************************************************ |
| 1427 | * MESSAGE ROUTING AND SOURCE VALIDATION * |
| 1428 | ************************************************************************/ |
| 1429 | |
| 1430 | int |
| 1431 | dmsg_circuit_relay(dmsg_msg_t *msg) |
| 1432 | { |
| 1433 | dmsg_iocom_t *iocom = msg->iocom; |
| 1434 | dmsg_circuit_t *circ; |
| 1435 | dmsg_circuit_t *peer; |
| 1436 | dmsg_circuit_t dummy; |
| 1437 | int error = 0; |
| 1438 | |
| 1439 | /* |
| 1440 | * Relay occurs before any state processing, msg state should always |
| 1441 | * be NULL. |
| 1442 | */ |
| 1443 | assert(msg->state == NULL); |
| 1444 | |
| 1445 | /* |
| 1446 | * Lookup the circuit on the incoming iocom. |
| 1447 | */ |
| 1448 | pthread_mutex_lock(&cluster_mtx); |
| 1449 | |
| 1450 | dummy.msgid = msg->any.head.circuit; |
| 1451 | circ = RB_FIND(dmsg_circuit_tree, &iocom->circuit_tree, &dummy); |
| 1452 | assert(circ); |
| 1453 | peer = circ->peer; |
| 1454 | |
| 1455 | msg->iocom = peer->iocom; |
| 1456 | msg->any.head.circuit = peer->msgid; |
| 1457 | |
| 1458 | pthread_mutex_unlock(&cluster_mtx); |
| 1459 | |
| 1460 | fprintf(stderr, "ROUTE MESSAGE VC %08x to %08x\n", |
| 1461 | (uint32_t)circ->msgid, (uint32_t)peer->msgid); /* brevity */ |
| 1462 | dmsg_msg_write(msg); |
| 1463 | error = DMSG_IOQ_ERROR_ROUTED; |
| 1464 | |
| 1465 | return error; |
| 1466 | } |
| 1467 | |
| 1468 | /************************************************************************ |
| 1469 | * ROUTER AND MESSAGING HANDLES * |
| 1470 | ************************************************************************ |
| 1471 | * |
| 1472 | * Basically the idea here is to provide a stable data structure which |
| 1473 | * can be localized to the caller for higher level protocols to work with. |
| 1474 | * Depends on the context, these dmsg_handle's can be pooled by use-case |
| 1475 | * and remain persistent through a client (or mount point's) life. |
| 1476 | */ |
| 1477 | |
| 1478 | #if 0 |
| 1479 | /* |
| 1480 | * Obtain a stable handle on a cluster given its uuid. This ties directly |
| 1481 | * into the global cluster topology, creating the structure if necessary |
| 1482 | * (even if the uuid does not exist or does not exist yet), and preventing |
| 1483 | * the structure from getting ripped out from under us while we hold a |
| 1484 | * pointer to it. |
| 1485 | */ |
| 1486 | h2span_cluster_t * |
| 1487 | dmsg_cluster_get(uuid_t *pfs_clid) |
| 1488 | { |
| 1489 | h2span_cluster_t dummy_cls; |
| 1490 | h2span_cluster_t *cls; |
| 1491 | |
| 1492 | dummy_cls.pfs_clid = *pfs_clid; |
| 1493 | pthread_mutex_lock(&cluster_mtx); |
| 1494 | cls = RB_FIND(h2span_cluster_tree, &cluster_tree, &dummy_cls); |
| 1495 | if (cls) |
| 1496 | ++cls->refs; |
| 1497 | pthread_mutex_unlock(&cluster_mtx); |
| 1498 | return (cls); |
| 1499 | } |
| 1500 | |
| 1501 | void |
| 1502 | dmsg_cluster_put(h2span_cluster_t *cls) |
| 1503 | { |
| 1504 | pthread_mutex_lock(&cluster_mtx); |
| 1505 | assert(cls->refs > 0); |
| 1506 | --cls->refs; |
| 1507 | if (RB_EMPTY(&cls->tree) && cls->refs == 0) { |
| 1508 | RB_REMOVE(h2span_cluster_tree, |
| 1509 | &cluster_tree, cls); |
| 1510 | dmsg_free(cls); |
| 1511 | } |
| 1512 | pthread_mutex_unlock(&cluster_mtx); |
| 1513 | } |
| 1514 | |
| 1515 | /* |
| 1516 | * Obtain a stable handle to a specific cluster node given its uuid. |
| 1517 | * This handle does NOT lock in the route to the node and is typically |
| 1518 | * used as part of the dmsg_handle_*() API to obtain a set of |
| 1519 | * stable nodes. |
| 1520 | */ |
| 1521 | h2span_node_t * |
| 1522 | dmsg_node_get(h2span_cluster_t *cls, uuid_t *pfs_fsid) |
| 1523 | { |
| 1524 | } |
| 1525 | |
| 1526 | #endif |
| 1527 | |
| 1528 | /* |
| 1529 | * Dumps the spanning tree |
| 1530 | */ |
| 1531 | void |
| 1532 | dmsg_shell_tree(dmsg_circuit_t *circuit, char *cmdbuf __unused) |
| 1533 | { |
| 1534 | h2span_cluster_t *cls; |
| 1535 | h2span_node_t *node; |
| 1536 | h2span_link_t *slink; |
| 1537 | char *uustr = NULL; |
| 1538 | |
| 1539 | pthread_mutex_lock(&cluster_mtx); |
| 1540 | RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) { |
| 1541 | dmsg_circuit_printf(circuit, "Cluster %s %s (%s)\n", |
| 1542 | dmsg_peer_type_to_str(cls->peer_type), |
| 1543 | dmsg_uuid_to_str(&cls->pfs_clid, &uustr), |
| 1544 | cls->cl_label); |
| 1545 | RB_FOREACH(node, h2span_node_tree, &cls->tree) { |
| 1546 | dmsg_circuit_printf(circuit, " Node %s %s (%s)\n", |
| 1547 | dmsg_pfs_type_to_str(node->pfs_type), |
| 1548 | dmsg_uuid_to_str(&node->pfs_fsid, &uustr), |
| 1549 | node->fs_label); |
| 1550 | RB_FOREACH(slink, h2span_link_tree, &node->tree) { |
| 1551 | dmsg_circuit_printf(circuit, |
| 1552 | "\tLink dist=%d via %d\n", |
| 1553 | slink->dist, |
| 1554 | slink->state->iocom->sock_fd); |
| 1555 | } |
| 1556 | } |
| 1557 | } |
| 1558 | pthread_mutex_unlock(&cluster_mtx); |
| 1559 | if (uustr) |
| 1560 | free(uustr); |
| 1561 | #if 0 |
| 1562 | TAILQ_FOREACH(conn, &connq, entry) { |
| 1563 | } |
| 1564 | #endif |
| 1565 | } |
| 1566 | |
| 1567 | /* |
| 1568 | * Random number sub-sort value to add to SPAN rnss fields on relay. |
| 1569 | * This allows us to differentiate spans with the same <dist> field |
| 1570 | * for relaying purposes. We must normally limit the number of relays |
| 1571 | * for any given SPAN origination but we must also guarantee that a |
| 1572 | * symmetric reverse path exists, so we use the rnss field as a sub-sort |
| 1573 | * (since there can be thousands or millions if we only match on <dist>), |
| 1574 | * and if there STILL too many spans we go past the limit. |
| 1575 | */ |
| 1576 | static |
| 1577 | uint32_t |
| 1578 | dmsg_rnss(void) |
| 1579 | { |
| 1580 | if (DMsgRNSS == 0) { |
| 1581 | pthread_mutex_lock(&cluster_mtx); |
| 1582 | while (DMsgRNSS == 0) { |
| 1583 | srandomdev(); |
| 1584 | DMsgRNSS = random(); |
| 1585 | } |
| 1586 | pthread_mutex_unlock(&cluster_mtx); |
| 1587 | } |
| 1588 | return(DMsgRNSS); |
| 1589 | } |