/* * Copyright (c) 2012-2014 The DragonFly Project. All rights reserved. * * This code is derived from software contributed to The DragonFly Project * by Matthew Dillon * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name of The DragonFly Project nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific, prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * LNK_SPAN PROTOCOL SUPPORT FUNCTIONS - Please see sys/dmsg.h for an * involved explanation of the protocol. */ #include "dmsg_local.h" /* * Maximum spanning tree distance. This has the practical effect of * stopping tail-chasing closed loops when a feeder span is lost. */ #define DMSG_SPAN_MAXDIST 16 /* * RED-BLACK TREE DEFINITIONS * * We need to track: * * (1) shared fsid's (a cluster). * (2) unique fsid's (a node in a cluster) <--- LNK_SPAN transactions. * * We need to aggegate all active LNK_SPANs, aggregate, and create our own * outgoing LNK_SPAN transactions on each of our connections representing * the aggregated state. * * h2span_conn - list of iocom connections who wish to receive SPAN * propagation from other connections. Might contain * a filter string. Only iocom's with an open * LNK_CONN transactions are applicable for SPAN * propagation. * * h2span_relay - List of links relayed (via SPAN). Essentially * each relay structure represents a LNK_SPAN * transaction that we initiated, verses h2span_link * which is a LNK_SPAN transaction that we received. * * -- * * h2span_cluster - Organizes the shared fsid's. One structure for * each cluster. * * h2span_node - Organizes the nodes in a cluster. One structure * for each unique {cluster,node}, aka {fsid, pfs_fsid}. * * h2span_link - Organizes all incoming and outgoing LNK_SPAN message * transactions related to a node. * * One h2span_link structure for each incoming LNK_SPAN * transaction. Links selected for propagation back * out are also where the outgoing LNK_SPAN messages * are indexed into (so we can propagate changes). * * The h2span_link's use a red-black tree to sort the * distance hop metric for the incoming LNK_SPAN. We * then select the top N for outgoing. When the * topology changes the top N may also change and cause * new outgoing LNK_SPAN transactions to be opened * and less desireable ones to be closed, causing * transactional aborts within the message flow in * the process. * * Also note - All outgoing LNK_SPAN message transactions are also * entered into a red-black tree for use by the routing * function. This is handled by msg.c in the state * code, not here. */ struct h2span_link; struct h2span_relay; TAILQ_HEAD(h2span_conn_queue, h2span_conn); TAILQ_HEAD(h2span_relay_queue, h2span_relay); RB_HEAD(h2span_cluster_tree, h2span_cluster); RB_HEAD(h2span_node_tree, h2span_node); RB_HEAD(h2span_link_tree, h2span_link); RB_HEAD(h2span_relay_tree, h2span_relay); uint32_t DMsgRNSS; /* * Received LNK_CONN transaction enables SPAN protocol over connection. * (may contain filter). Typically one for each mount and several may * share the same media. */ struct h2span_conn { TAILQ_ENTRY(h2span_conn) entry; struct h2span_relay_tree tree; dmsg_state_t *state; dmsg_lnk_conn_t lnk_conn; }; /* * All received LNK_SPANs are organized by cluster (pfs_clid), * node (pfs_fsid), and link (received LNK_SPAN transaction). */ struct h2span_cluster { RB_ENTRY(h2span_cluster) rbnode; struct h2span_node_tree tree; uuid_t pfs_clid; /* shared fsid */ uint8_t peer_type; char cl_label[128]; /* cluster label (typ PEER_BLOCK) */ int refs; /* prevents destruction */ }; struct h2span_node { RB_ENTRY(h2span_node) rbnode; struct h2span_link_tree tree; struct h2span_cluster *cls; uint8_t pfs_type; uuid_t pfs_fsid; /* unique fsid */ char fs_label[128]; /* fs label (typ PEER_HAMMER2) */ void *opaque; }; struct h2span_link { RB_ENTRY(h2span_link) rbnode; dmsg_state_t *state; /* state<->link */ struct h2span_node *node; /* related node */ struct h2span_relay_queue relayq; /* relay out */ dmsg_lnk_span_t lnk_span; }; /* * Any LNK_SPAN transactions we receive which are relayed out other * connections utilize this structure to track the LNK_SPAN transactions * we initiate (relay out) on other connections. We only relay out * LNK_SPANs on connections we have an open CONN transaction for. * * The relay structure points to the outgoing LNK_SPAN trans (out_state) * and to the incoming LNK_SPAN transaction (in_state). The relay * structure holds refs on the related states. * * In many respects this is the core of the protocol... actually figuring * out what LNK_SPANs to relay. The spanid used for relaying is the * address of the 'state' structure, which is why h2span_relay has to * be entered into a RB-TREE based at h2span_conn (so we can look * up the spanid to validate it). */ struct h2span_relay { TAILQ_ENTRY(h2span_relay) entry; /* from link */ RB_ENTRY(h2span_relay) rbnode; /* from h2span_conn */ struct h2span_conn *conn; /* related CONN transaction */ dmsg_state_t *source_rt; /* h2span_link state */ dmsg_state_t *target_rt; /* h2span_relay state */ }; typedef struct h2span_conn h2span_conn_t; typedef struct h2span_cluster h2span_cluster_t; typedef struct h2span_node h2span_node_t; typedef struct h2span_link h2span_link_t; typedef struct h2span_relay h2span_relay_t; #define dmsg_termstr(array) _dmsg_termstr((array), sizeof(array)) static h2span_relay_t *dmsg_generate_relay(h2span_conn_t *conn, h2span_link_t *slink); static uint32_t dmsg_rnss(void); static __inline void _dmsg_termstr(char *base, size_t size) { base[size-1] = 0; } /* * Cluster peer_type, uuid, AND label must match for a match */ static int h2span_cluster_cmp(h2span_cluster_t *cls1, h2span_cluster_t *cls2) { int r; if (cls1->peer_type < cls2->peer_type) return(-1); if (cls1->peer_type > cls2->peer_type) return(1); r = uuid_compare(&cls1->pfs_clid, &cls2->pfs_clid, NULL); if (r == 0) r = strcmp(cls1->cl_label, cls2->cl_label); return r; } /* * Match against fs_label/pfs_fsid. Together these two items represent a * unique node. In most cases the primary differentiator is pfs_fsid but * we also string-match fs_label. */ static int h2span_node_cmp(h2span_node_t *node1, h2span_node_t *node2) { int r; r = strcmp(node1->fs_label, node2->fs_label); if (r == 0) r = uuid_compare(&node1->pfs_fsid, &node2->pfs_fsid, NULL); return (r); } /* * Sort/subsort must match h2span_relay_cmp() under any given node * to make the aggregation algorithm easier, so the best links are * in the same sorted order as the best relays. * * NOTE: We cannot use link*->state->msgid because this msgid is created * by each remote host and thus might wind up being the same. */ static int h2span_link_cmp(h2span_link_t *link1, h2span_link_t *link2) { if (link1->lnk_span.dist < link2->lnk_span.dist) return(-1); if (link1->lnk_span.dist > link2->lnk_span.dist) return(1); if (link1->lnk_span.rnss < link2->lnk_span.rnss) return(-1); if (link1->lnk_span.rnss > link2->lnk_span.rnss) return(1); #if 1 if ((uintptr_t)link1->state < (uintptr_t)link2->state) return(-1); if ((uintptr_t)link1->state > (uintptr_t)link2->state) return(1); #else if (link1->state->msgid < link2->state->msgid) return(-1); if (link1->state->msgid > link2->state->msgid) return(1); #endif return(0); } /* * Relay entries are sorted by node, subsorted by distance and link * address (so we can match up the conn->tree relay topology with * a node's link topology). */ static int h2span_relay_cmp(h2span_relay_t *relay1, h2span_relay_t *relay2) { h2span_link_t *link1 = relay1->source_rt->any.link; h2span_link_t *link2 = relay2->source_rt->any.link; if ((intptr_t)link1->node < (intptr_t)link2->node) return(-1); if ((intptr_t)link1->node > (intptr_t)link2->node) return(1); if (link1->lnk_span.dist < link2->lnk_span.dist) return(-1); if (link1->lnk_span.dist > link2->lnk_span.dist) return(1); if (link1->lnk_span.rnss < link2->lnk_span.rnss) return(-1); if (link1->lnk_span.rnss > link2->lnk_span.rnss) return(1); #if 1 if ((uintptr_t)link1->state < (uintptr_t)link2->state) return(-1); if ((uintptr_t)link1->state > (uintptr_t)link2->state) return(1); #else if (link1->state->msgid < link2->state->msgid) return(-1); if (link1->state->msgid > link2->state->msgid) return(1); #endif return(0); } RB_PROTOTYPE_STATIC(h2span_cluster_tree, h2span_cluster, rbnode, h2span_cluster_cmp); RB_PROTOTYPE_STATIC(h2span_node_tree, h2span_node, rbnode, h2span_node_cmp); RB_PROTOTYPE_STATIC(h2span_link_tree, h2span_link, rbnode, h2span_link_cmp); RB_PROTOTYPE_STATIC(h2span_relay_tree, h2span_relay, rbnode, h2span_relay_cmp); RB_GENERATE_STATIC(h2span_cluster_tree, h2span_cluster, rbnode, h2span_cluster_cmp); RB_GENERATE_STATIC(h2span_node_tree, h2span_node, rbnode, h2span_node_cmp); RB_GENERATE_STATIC(h2span_link_tree, h2span_link, rbnode, h2span_link_cmp); RB_GENERATE_STATIC(h2span_relay_tree, h2span_relay, rbnode, h2span_relay_cmp); /* * Global mutex protects cluster_tree lookups, connq, mediaq. */ static pthread_mutex_t cluster_mtx; static struct h2span_cluster_tree cluster_tree = RB_INITIALIZER(cluster_tree); static struct h2span_conn_queue connq = TAILQ_HEAD_INITIALIZER(connq); static struct dmsg_media_queue mediaq = TAILQ_HEAD_INITIALIZER(mediaq); static void dmsg_lnk_span(dmsg_msg_t *msg); static void dmsg_lnk_conn(dmsg_msg_t *msg); static void dmsg_lnk_relay(dmsg_msg_t *msg); static void dmsg_relay_scan(h2span_conn_t *conn, h2span_node_t *node); static void dmsg_relay_delete(h2span_relay_t *relay); void dmsg_msg_lnk_signal(dmsg_iocom_t *iocom __unused) { pthread_mutex_lock(&cluster_mtx); dmsg_relay_scan(NULL, NULL); pthread_mutex_unlock(&cluster_mtx); } /* * DMSG_PROTO_LNK - Generic DMSG_PROTO_LNK. * (incoming iocom lock not held) * * This function is typically called for one-way and opening-transactions * since state->func is assigned after that, but it will also be called * if no state->func is assigned on transaction-open. */ void dmsg_msg_lnk(dmsg_msg_t *msg) { dmsg_iocom_t *iocom = msg->state->iocom; switch(msg->tcmd & DMSGF_BASECMDMASK) { case DMSG_LNK_CONN: dmsg_lnk_conn(msg); break; case DMSG_LNK_SPAN: dmsg_lnk_span(msg); break; default: iocom->usrmsg_callback(msg, 1); /* state invalid after reply */ break; } } /* * LNK_CONN - iocom identify message reception. * (incoming iocom lock not held) * * Remote node identifies itself to us, sets up a SPAN filter, and gives us * the ok to start transmitting SPANs. */ void dmsg_lnk_conn(dmsg_msg_t *msg) { dmsg_state_t *state = msg->state; dmsg_iocom_t *iocom = state->iocom; dmsg_media_t *media; h2span_conn_t *conn; h2span_relay_t *relay; char *alloc = NULL; pthread_mutex_lock(&cluster_mtx); fprintf(stderr, "dmsg_lnk_conn: msg %p cmd %08x state %p " "txcmd %08x rxcmd %08x\n", msg, msg->any.head.cmd, state, state->txcmd, state->rxcmd); switch(msg->any.head.cmd & DMSGF_TRANSMASK) { case DMSG_LNK_CONN | DMSGF_CREATE: case DMSG_LNK_CONN | DMSGF_CREATE | DMSGF_DELETE: /* * On transaction start we allocate a new h2span_conn and * acknowledge the request, leaving the transaction open. * We then relay priority-selected SPANs. */ fprintf(stderr, "LNK_CONN(%08x): %s/%s/%s\n", (uint32_t)msg->any.head.msgid, dmsg_uuid_to_str(&msg->any.lnk_conn.pfs_clid, &alloc), msg->any.lnk_conn.cl_label, msg->any.lnk_conn.fs_label); free(alloc); conn = dmsg_alloc(sizeof(*conn)); assert(state->iocom->conn == NULL); RB_INIT(&conn->tree); state->iocom->conn = conn; /* XXX only one */ state->iocom->conn_msgid = state->msgid; conn->state = state; state->func = dmsg_lnk_conn; state->any.conn = conn; TAILQ_INSERT_TAIL(&connq, conn, entry); conn->lnk_conn = msg->any.lnk_conn; /* * Set up media */ TAILQ_FOREACH(media, &mediaq, entry) { if (uuid_compare(&msg->any.lnk_conn.mediaid, &media->mediaid, NULL) == 0) { break; } } if (media == NULL) { media = dmsg_alloc(sizeof(*media)); media->mediaid = msg->any.lnk_conn.mediaid; TAILQ_INSERT_TAIL(&mediaq, media, entry); } state->media = media; ++media->refs; if ((msg->any.head.cmd & DMSGF_DELETE) == 0) { iocom->usrmsg_callback(msg, 0); dmsg_msg_result(msg, 0); dmsg_iocom_signal(iocom); break; } /* FALL THROUGH */ case DMSG_LNK_CONN | DMSGF_DELETE: case DMSG_LNK_ERROR | DMSGF_DELETE: /* * On transaction terminate we clean out our h2span_conn * and acknowledge the request, closing the transaction. */ fprintf(stderr, "LNK_CONN: Terminated\n"); conn = state->any.conn; assert(conn); /* * Adjust media refs * * Callback will clean out media config / user-opaque state */ media = state->media; --media->refs; if (media->refs == 0) { fprintf(stderr, "Media shutdown\n"); TAILQ_REMOVE(&mediaq, media, entry); pthread_mutex_unlock(&cluster_mtx); iocom->usrmsg_callback(msg, 0); pthread_mutex_lock(&cluster_mtx); dmsg_free(media); } state->media = NULL; /* * Clean out all relays. This requires terminating each * relay transaction. */ while ((relay = RB_ROOT(&conn->tree)) != NULL) { dmsg_relay_delete(relay); } /* * Clean out conn */ conn->state = NULL; msg->state->any.conn = NULL; msg->state->iocom->conn = NULL; TAILQ_REMOVE(&connq, conn, entry); dmsg_free(conn); dmsg_msg_reply(msg, 0); /* state invalid after reply */ break; default: iocom->usrmsg_callback(msg, 1); #if 0 if (msg->any.head.cmd & DMSGF_DELETE) goto deleteconn; dmsg_msg_reply(msg, DMSG_ERR_NOSUPP); #endif break; } pthread_mutex_unlock(&cluster_mtx); } /* * LNK_SPAN - Spanning tree protocol message reception * (incoming iocom lock not held) * * Receive a spanning tree transactional message, creating or destroying * a SPAN and propagating it to other iocoms. */ void dmsg_lnk_span(dmsg_msg_t *msg) { dmsg_state_t *state = msg->state; dmsg_iocom_t *iocom = state->iocom; h2span_cluster_t dummy_cls; h2span_node_t dummy_node; h2span_cluster_t *cls; h2span_node_t *node; h2span_link_t *slink; h2span_relay_t *relay; char *alloc = NULL; /* * Ignore reply to LNK_SPAN. The reply is expected and will commands * to flow in both directions on the open transaction. This will also * ignore DMSGF_REPLY|DMSGF_DELETE messages. Since we take no action * if the other end unexpectedly closes their side of the transaction, * we can ignore that too. */ if (msg->any.head.cmd & DMSGF_REPLY) { printf("Ignore reply to LNK_SPAN\n"); return; } pthread_mutex_lock(&cluster_mtx); /* * On transaction start we initialize the tracking infrastructure */ if (msg->any.head.cmd & DMSGF_CREATE) { assert(state->func == NULL); state->func = dmsg_lnk_span; dmsg_termstr(msg->any.lnk_span.cl_label); dmsg_termstr(msg->any.lnk_span.fs_label); /* * Find the cluster */ dummy_cls.pfs_clid = msg->any.lnk_span.pfs_clid; dummy_cls.peer_type = msg->any.lnk_span.peer_type; bcopy(msg->any.lnk_span.cl_label, dummy_cls.cl_label, sizeof(dummy_cls.cl_label)); cls = RB_FIND(h2span_cluster_tree, &cluster_tree, &dummy_cls); if (cls == NULL) { cls = dmsg_alloc(sizeof(*cls)); cls->pfs_clid = msg->any.lnk_span.pfs_clid; cls->peer_type = msg->any.lnk_span.peer_type; bcopy(msg->any.lnk_span.cl_label, cls->cl_label, sizeof(cls->cl_label)); RB_INIT(&cls->tree); RB_INSERT(h2span_cluster_tree, &cluster_tree, cls); } /* * Find the node */ dummy_node.pfs_fsid = msg->any.lnk_span.pfs_fsid; bcopy(msg->any.lnk_span.fs_label, dummy_node.fs_label, sizeof(dummy_node.fs_label)); node = RB_FIND(h2span_node_tree, &cls->tree, &dummy_node); if (node == NULL) { node = dmsg_alloc(sizeof(*node)); node->pfs_fsid = msg->any.lnk_span.pfs_fsid; node->pfs_type = msg->any.lnk_span.pfs_type; bcopy(msg->any.lnk_span.fs_label, node->fs_label, sizeof(node->fs_label)); node->cls = cls; RB_INIT(&node->tree); RB_INSERT(h2span_node_tree, &cls->tree, node); } /* * Create the link * * NOTE: Sub-transactions on the incoming SPAN can be used * to talk to the originator. We should not set-up * state->relay for incoming SPANs since our sub-trans * is running on the same interface (i.e. no actual * relaying need be done). * * NOTE: Later on when we relay the SPAN out the outgoing * SPAN state will be set up to relay back to this * state. * * NOTE: It is possible for SPAN targets to send one-way * messages to the originator but it is not possible * for the originator to (currently) broadcast one-way * messages to all of its SPAN targets. The protocol * allows such a feature to be added in the future. */ assert(state->any.link == NULL); slink = dmsg_alloc(sizeof(*slink)); TAILQ_INIT(&slink->relayq); slink->node = node; slink->state = state; state->any.link = slink; slink->lnk_span = msg->any.lnk_span; RB_INSERT(h2span_link_tree, &node->tree, slink); fprintf(stderr, "LNK_SPAN(thr %p): %p %s cl=%s fs=%s dist=%d\n", iocom, slink, dmsg_uuid_to_str(&msg->any.lnk_span.pfs_clid, &alloc), msg->any.lnk_span.cl_label, msg->any.lnk_span.fs_label, msg->any.lnk_span.dist); free(alloc); #if 0 dmsg_relay_scan(NULL, node); #endif /* * Ack the open, which will issue a CREATE on our side, and * leave the transaction open. Necessary to allow the * transaction to be used as a virtual circuit. */ dmsg_state_result(state, 0); dmsg_iocom_signal(iocom); } /* * On transaction terminate we remove the tracking infrastructure. */ if (msg->any.head.cmd & DMSGF_DELETE) { slink = state->any.link; assert(slink != NULL); node = slink->node; cls = node->cls; fprintf(stderr, "LNK_DELE(thr %p): %p %s cl=%s fs=%s\n", iocom, slink, dmsg_uuid_to_str(&cls->pfs_clid, &alloc), cls->cl_label, node->fs_label); free(alloc); /* * Clean out all relays. This requires terminating each * relay transaction. */ while ((relay = TAILQ_FIRST(&slink->relayq)) != NULL) { dmsg_relay_delete(relay); } /* * Clean out the topology */ RB_REMOVE(h2span_link_tree, &node->tree, slink); if (RB_EMPTY(&node->tree)) { RB_REMOVE(h2span_node_tree, &cls->tree, node); if (RB_EMPTY(&cls->tree) && cls->refs == 0) { RB_REMOVE(h2span_cluster_tree, &cluster_tree, cls); dmsg_free(cls); } node->cls = NULL; dmsg_free(node); node = NULL; } state->any.link = NULL; slink->state = NULL; slink->node = NULL; dmsg_free(slink); /* * We have to terminate the transaction */ dmsg_state_reply(state, 0); /* state invalid after reply */ /* * If the node still exists issue any required updates. If * it doesn't then all related relays have already been * removed and there's nothing left to do. */ #if 0 if (node) dmsg_relay_scan(NULL, node); #endif if (node) dmsg_iocom_signal(iocom); } pthread_mutex_unlock(&cluster_mtx); } /* * Update relay transactions for SPANs. * * Called with cluster_mtx held. */ static void dmsg_relay_scan_specific(h2span_node_t *node, h2span_conn_t *conn); static void dmsg_relay_scan(h2span_conn_t *conn, h2span_node_t *node) { h2span_cluster_t *cls; if (node) { /* * Iterate specific node */ TAILQ_FOREACH(conn, &connq, entry) dmsg_relay_scan_specific(node, conn); } else { /* * Full iteration. * * Iterate cluster ids, nodes, and either a specific connection * or all connections. */ RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) { /* * Iterate node ids */ RB_FOREACH(node, h2span_node_tree, &cls->tree) { /* * Synchronize the node's link (received SPANs) * with each connection's relays. */ if (conn) { dmsg_relay_scan_specific(node, conn); } else { TAILQ_FOREACH(conn, &connq, entry) { dmsg_relay_scan_specific(node, conn); } assert(conn == NULL); } } } } } /* * Update the relay'd SPANs for this (node, conn). * * Iterate links and adjust relays to match. We only propagate the top link * for now (XXX we want to propagate the top two). * * The dmsg_relay_scan_cmp() function locates the first relay element * for any given node. The relay elements will be sub-sorted by dist. */ struct relay_scan_info { h2span_node_t *node; h2span_relay_t *relay; }; static int dmsg_relay_scan_cmp(h2span_relay_t *relay, void *arg) { struct relay_scan_info *info = arg; if ((intptr_t)relay->source_rt->any.link->node < (intptr_t)info->node) return(-1); if ((intptr_t)relay->source_rt->any.link->node > (intptr_t)info->node) return(1); return(0); } static int dmsg_relay_scan_callback(h2span_relay_t *relay, void *arg) { struct relay_scan_info *info = arg; info->relay = relay; return(-1); } static void dmsg_relay_scan_specific(h2span_node_t *node, h2span_conn_t *conn) { struct relay_scan_info info; h2span_relay_t *relay; h2span_relay_t *next_relay; h2span_link_t *slink; dmsg_lnk_conn_t *lconn; dmsg_lnk_span_t *lspan; int count; int maxcount = 2; #ifdef REQUIRE_SYMMETRICAL uint32_t lastdist = DMSG_SPAN_MAXDIST; uint32_t lastrnss = 0; #endif info.node = node; info.relay = NULL; /* * Locate the first related relay for the node on this connection. * relay will be NULL if there were none. */ RB_SCAN(h2span_relay_tree, &conn->tree, dmsg_relay_scan_cmp, dmsg_relay_scan_callback, &info); relay = info.relay; info.relay = NULL; if (relay) assert(relay->source_rt->any.link->node == node); if (DMsgDebugOpt > 8) fprintf(stderr, "relay scan for connection %p\n", conn); /* * Iterate the node's links (received SPANs) in distance order, * lowest (best) dist first. * * PROPAGATE THE BEST LINKS OVER THE SPECIFIED CONNECTION. * * Track relays while iterating the best links and construct * missing relays when necessary. * * (If some prior better link was removed it would have also * removed the relay, so the relay can only match exactly or * be worse). */ count = 0; RB_FOREACH(slink, h2span_link_tree, &node->tree) { /* * Increment count of successful relays. This isn't * quite accurate if we break out but nothing after * the loop uses (count). * * If count exceeds the maximum number of relays we desire * we normally want to break out. However, in order to * guarantee a symmetric path we have to continue if both * (dist) and (rnss) continue to match. Otherwise the SPAN * propagation in the reverse direction may choose different * routes and we will not have a symmetric path. * * NOTE: Spanning tree does not have to be symmetrical so * this code is not currently enabled. */ if (++count >= maxcount) { #ifdef REQUIRE_SYMMETRICAL if (lastdist != slink->lnk_span.dist || lastrnss != slink->lnk_span.rnss) { break; } #else break; #endif /* go beyond the nominal maximum desired relays */ } /* * Match, relay already in-place, get the next * relay to match against the next slink. */ if (relay && relay->source_rt->any.link == slink) { relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay); continue; } /* * We might want this SLINK, if it passes our filters. * * The spanning tree can cause closed loops so we have * to limit slink->dist. */ if (slink->lnk_span.dist > DMSG_SPAN_MAXDIST) break; /* * Don't bother transmitting a LNK_SPAN out the same * connection it came in on. Trivial optimization. */ if (slink->state->iocom == conn->state->iocom) break; /* * NOTE ON FILTERS: The protocol spec allows non-requested * SPANs to be transmitted, the other end is expected to * leave their transactions open but otherwise ignore them. * * Don't bother transmitting if the remote connection * is not accepting this SPAN's peer_type. * * pfs_mask is typically used so pure clients can filter * out receiving SPANs for other pure clients. */ lspan = &slink->lnk_span; lconn = &conn->lnk_conn; if (((1LLU << lspan->peer_type) & lconn->peer_mask) == 0) break; if (((1LLU << lspan->pfs_type) & lconn->pfs_mask) == 0) break; /* * Do not give pure clients visibility to other pure clients */ if (lconn->pfs_type == DMSG_PFSTYPE_CLIENT && lspan->pfs_type == DMSG_PFSTYPE_CLIENT) { break; } /* * Connection filter, if cluster uuid is not NULL it must * match the span cluster uuid. Only applies when the * peer_type matches. */ if (lspan->peer_type == lconn->peer_type && !uuid_is_nil(&lconn->pfs_clid, NULL) && uuid_compare(&slink->node->cls->pfs_clid, &lconn->pfs_clid, NULL)) { break; } /* * Connection filter, if cluster label is not empty it must * match the span cluster label. Only applies when the * peer_type matches. */ if (lspan->peer_type == lconn->peer_type && lconn->cl_label[0] && strcmp(lconn->cl_label, slink->node->cls->cl_label)) { break; } /* * NOTE! pfs_fsid differentiates nodes within the same cluster * so we obviously don't want to match those. Similarly * for fs_label. */ /* * Ok, we've accepted this SPAN for relaying. */ assert(relay == NULL || relay->source_rt->any.link->node != slink->node || relay->source_rt->any.link->lnk_span.dist >= slink->lnk_span.dist); relay = dmsg_generate_relay(conn, slink); #ifdef REQUIRE_SYMMETRICAL lastdist = slink->lnk_span.dist; lastrnss = slink->lnk_span.rnss; #endif /* * Match (created new relay), get the next relay to * match against the next slink. */ relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay); } /* * Any remaining relay's belonging to this connection which match * the node are in excess of the current aggregate spanning state * and should be removed. */ while (relay && relay->source_rt->any.link->node == node) { next_relay = RB_NEXT(h2span_relay_tree, &conn->tree, relay); fprintf(stderr, "RELAY DELETE FROM EXTRAS\n"); dmsg_relay_delete(relay); relay = next_relay; } } /* * Find the slink associated with the msgid and return its state, * so the caller can issue a transaction. */ dmsg_state_t * dmsg_findspan(const char *label) { dmsg_state_t *state; h2span_cluster_t *cls; h2span_node_t *node; h2span_link_t *slink; uint64_t msgid = strtoull(label, NULL, 16); pthread_mutex_lock(&cluster_mtx); state = NULL; RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) { RB_FOREACH(node, h2span_node_tree, &cls->tree) { RB_FOREACH(slink, h2span_link_tree, &node->tree) { if (slink->state->msgid == msgid) { state = slink->state; goto done; } } } } done: pthread_mutex_unlock(&cluster_mtx); fprintf(stderr, "findspan: %p\n", state); return state; } /* * Helper function to generate missing relay on target connection. * * cluster_mtx must be held */ static h2span_relay_t * dmsg_generate_relay(h2span_conn_t *conn, h2span_link_t *slink) { h2span_relay_t *relay; dmsg_msg_t *msg; relay = dmsg_alloc(sizeof(*relay)); relay->conn = conn; relay->source_rt = slink->state; /* relay->source_rt->any.link = slink; */ /* * NOTE: relay->target_rt->any.relay set to relay by alloc. * * NOTE: LNK_SPAN is transmitted as a top-level transaction. */ msg = dmsg_msg_alloc(&conn->state->iocom->state0, 0, DMSG_LNK_SPAN | DMSGF_CREATE, dmsg_lnk_relay, relay); relay->target_rt = msg->state; msg->any.lnk_span = slink->lnk_span; msg->any.lnk_span.dist = slink->lnk_span.dist + 1; msg->any.lnk_span.rnss = slink->lnk_span.rnss + dmsg_rnss(); RB_INSERT(h2span_relay_tree, &conn->tree, relay); TAILQ_INSERT_TAIL(&slink->relayq, relay, entry); /* * Seed the relay so new sub-transactions received on the outgoing * SPAN circuit are relayed back to the originator. */ msg->state->relay = relay->source_rt; dmsg_state_hold(msg->state->relay); dmsg_msg_write(msg); return (relay); } /* * Messages received on relay SPANs. These are open transactions so it is * in fact possible for the other end to close the transaction. * * XXX MPRACE on state structure */ static void dmsg_lnk_relay(dmsg_msg_t *msg) { dmsg_state_t *state = msg->state; h2span_relay_t *relay; assert(msg->any.head.cmd & DMSGF_REPLY); if (msg->any.head.cmd & DMSGF_DELETE) { pthread_mutex_lock(&cluster_mtx); fprintf(stderr, "RELAY DELETE FROM LNK_RELAY MSG\n"); if ((relay = state->any.relay) != NULL) { dmsg_relay_delete(relay); } else { dmsg_state_reply(state, 0); } pthread_mutex_unlock(&cluster_mtx); } } /* * cluster_mtx held by caller */ static void dmsg_relay_delete(h2span_relay_t *relay) { fprintf(stderr, "RELAY DELETE %p RELAY %p ON CLS=%p NODE=%p " "DIST=%d FD %d STATE %p\n", relay->source_rt->any.link, relay, relay->source_rt->any.link->node->cls, relay->source_rt->any.link->node, relay->source_rt->any.link->lnk_span.dist, relay->conn->state->iocom->sock_fd, relay->target_rt); RB_REMOVE(h2span_relay_tree, &relay->conn->tree, relay); TAILQ_REMOVE(&relay->source_rt->any.link->relayq, relay, entry); if (relay->target_rt) { relay->target_rt->any.relay = NULL; dmsg_state_reply(relay->target_rt, 0); /* state invalid after reply */ relay->target_rt = NULL; } /* * NOTE: relay->source_rt->refs is held by the relay SPAN * state, not by this relay structure. */ relay->conn = NULL; relay->source_rt = NULL; dmsg_free(relay); } /************************************************************************ * ROUTER AND MESSAGING HANDLES * ************************************************************************ * * Basically the idea here is to provide a stable data structure which * can be localized to the caller for higher level protocols to work with. * Depends on the context, these dmsg_handle's can be pooled by use-case * and remain persistent through a client (or mount point's) life. */ #if 0 /* * Obtain a stable handle on a cluster given its uuid. This ties directly * into the global cluster topology, creating the structure if necessary * (even if the uuid does not exist or does not exist yet), and preventing * the structure from getting ripped out from under us while we hold a * pointer to it. */ h2span_cluster_t * dmsg_cluster_get(uuid_t *pfs_clid) { h2span_cluster_t dummy_cls; h2span_cluster_t *cls; dummy_cls.pfs_clid = *pfs_clid; pthread_mutex_lock(&cluster_mtx); cls = RB_FIND(h2span_cluster_tree, &cluster_tree, &dummy_cls); if (cls) ++cls->refs; pthread_mutex_unlock(&cluster_mtx); return (cls); } void dmsg_cluster_put(h2span_cluster_t *cls) { pthread_mutex_lock(&cluster_mtx); assert(cls->refs > 0); --cls->refs; if (RB_EMPTY(&cls->tree) && cls->refs == 0) { RB_REMOVE(h2span_cluster_tree, &cluster_tree, cls); dmsg_free(cls); } pthread_mutex_unlock(&cluster_mtx); } /* * Obtain a stable handle to a specific cluster node given its uuid. * This handle does NOT lock in the route to the node and is typically * used as part of the dmsg_handle_*() API to obtain a set of * stable nodes. */ h2span_node_t * dmsg_node_get(h2span_cluster_t *cls, uuid_t *pfs_fsid) { } #endif /* * Dumps the spanning tree * * DEBUG ONLY */ void dmsg_shell_tree(dmsg_iocom_t *iocom, char *cmdbuf __unused) { h2span_cluster_t *cls; h2span_node_t *node; h2span_link_t *slink; h2span_relay_t *relay; char *uustr = NULL; pthread_mutex_lock(&cluster_mtx); RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) { dmsg_printf(iocom, "Cluster %s %s (%s)\n", dmsg_peer_type_to_str(cls->peer_type), dmsg_uuid_to_str(&cls->pfs_clid, &uustr), cls->cl_label); RB_FOREACH(node, h2span_node_tree, &cls->tree) { dmsg_printf(iocom, " Node %02x %s (%s)\n", node->pfs_type, dmsg_uuid_to_str(&node->pfs_fsid, &uustr), node->fs_label); RB_FOREACH(slink, h2span_link_tree, &node->tree) { dmsg_printf(iocom, "\tSLink msgid %016jx " "dist=%d via %d\n", (intmax_t)slink->state->msgid, slink->lnk_span.dist, slink->state->iocom->sock_fd); TAILQ_FOREACH(relay, &slink->relayq, entry) { dmsg_printf(iocom, "\t Relay-out msgid %016jx " "via %d\n", (intmax_t)relay->target_rt->msgid, relay->target_rt->iocom->sock_fd); } } } } pthread_mutex_unlock(&cluster_mtx); if (uustr) free(uustr); #if 0 TAILQ_FOREACH(conn, &connq, entry) { } #endif } /* * DEBUG ONLY * * Locate the state representing an incoming LNK_SPAN given its msgid. */ int dmsg_debug_findspan(uint64_t msgid, dmsg_state_t **statep) { h2span_cluster_t *cls; h2span_node_t *node; h2span_link_t *slink; pthread_mutex_lock(&cluster_mtx); RB_FOREACH(cls, h2span_cluster_tree, &cluster_tree) { RB_FOREACH(node, h2span_node_tree, &cls->tree) { RB_FOREACH(slink, h2span_link_tree, &node->tree) { if (slink->state->msgid == msgid) { *statep = slink->state; goto found; } } } } pthread_mutex_unlock(&cluster_mtx); *statep = NULL; return(ENOENT); found: pthread_mutex_unlock(&cluster_mtx); return(0); } /* * Random number sub-sort value to add to SPAN rnss fields on relay. * This allows us to differentiate spans with the same field * for relaying purposes. We must normally limit the number of relays * for any given SPAN origination but we must also guarantee that a * symmetric reverse path exists, so we use the rnss field as a sub-sort * (since there can be thousands or millions if we only match on ), * and if there STILL too many spans we go past the limit. */ static uint32_t dmsg_rnss(void) { if (DMsgRNSS == 0) { pthread_mutex_lock(&cluster_mtx); while (DMsgRNSS == 0) { srandomdev(); DMsgRNSS = random(); } pthread_mutex_unlock(&cluster_mtx); } return(DMsgRNSS); }