From 98e1b60ecc441625c91013e88f14cbd1b3c1fa08 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Fri, 14 Jun 2013 04:56:12 -0500 Subject: [PATCH] dlm: try other IPs when sctp init assoc fails Currently, if we cannot create a association to the first IP addr that is added to DLM, the SCTP init assoc code will just retry the same IP. This patch adds a simple failover schemes where we will try one of the addresses that was passed into DLM. Signed-off-by: Mike Christie Signed-off-by: David Teigland --- fs/dlm/lowcomms.c | 61 ++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 50 insertions(+), 11 deletions(-) diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c index 87e68dd01479..56015c9e8d00 100644 --- a/fs/dlm/lowcomms.c +++ b/fs/dlm/lowcomms.c @@ -126,6 +126,7 @@ struct connection { struct connection *othercon; struct work_struct rwork; /* Receive workqueue */ struct work_struct swork; /* Send workqueue */ + bool try_new_addr; }; #define sock2con(x) ((struct connection *)(x)->sk_user_data) @@ -144,6 +145,7 @@ struct dlm_node_addr { struct list_head list; int nodeid; int addr_count; + int curr_addr_index; struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT]; }; @@ -310,7 +312,7 @@ static int addr_compare(struct sockaddr_storage *x, struct sockaddr_storage *y) } static int nodeid_to_addr(int nodeid, struct sockaddr_storage *sas_out, - struct sockaddr *sa_out) + struct sockaddr *sa_out, bool try_new_addr) { struct sockaddr_storage sas; struct dlm_node_addr *na; @@ -320,8 +322,16 @@ static int nodeid_to_addr(int nodeid, struct sockaddr_storage *sas_out, spin_lock(&dlm_node_addrs_spin); na = find_node_addr(nodeid); - if (na && na->addr_count) - memcpy(&sas, na->addr[0], sizeof(struct sockaddr_storage)); + if (na && na->addr_count) { + if (try_new_addr) { + na->curr_addr_index++; + if (na->curr_addr_index == na->addr_count) + na->curr_addr_index = 0; + } + + memcpy(&sas, na->addr[na->curr_addr_index ], + sizeof(struct sockaddr_storage)); + } spin_unlock(&dlm_node_addrs_spin); if (!na) @@ -353,19 +363,22 @@ static int addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid) { struct dlm_node_addr *na; int rv = -EEXIST; + int addr_i; spin_lock(&dlm_node_addrs_spin); list_for_each_entry(na, &dlm_node_addrs, list) { if (!na->addr_count) continue; - if (!addr_compare(na->addr[0], addr)) - continue; - - *nodeid = na->nodeid; - rv = 0; - break; + for (addr_i = 0; addr_i < na->addr_count; addr_i++) { + if (addr_compare(na->addr[addr_i], addr)) { + *nodeid = na->nodeid; + rv = 0; + goto unlock; + } + } } +unlock: spin_unlock(&dlm_node_addrs_spin); return rv; } @@ -561,6 +574,21 @@ static void sctp_send_shutdown(sctp_assoc_t associd) static void sctp_init_failed_foreach(struct connection *con) { + + /* + * Don't try to recover base con and handle race where the + * other node's assoc init creates a assoc and we get that + * notification, then we get a notification that our attempt + * failed due. This happens when we are still trying the primary + * address, but the other node has already tried secondary addrs + * and found one that worked. + */ + if (!con->nodeid || con->sctp_assoc) + return; + + log_print("Retrying SCTP association init for node %d\n", con->nodeid); + + con->try_new_addr = true; con->sctp_assoc = 0; if (test_and_clear_bit(CF_INIT_PENDING, &con->flags)) { if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) @@ -663,6 +691,7 @@ static void process_sctp_notification(struct connection *con, nodeid, (int)sn->sn_assoc_change.sac_assoc_id); new_con->sctp_assoc = sn->sn_assoc_change.sac_assoc_id; + new_con->try_new_addr = false; /* Send any pending writes */ clear_bit(CF_CONNECT_PENDING, &new_con->flags); clear_bit(CF_INIT_PENDING, &new_con->flags); @@ -984,7 +1013,8 @@ static void sctp_init_assoc(struct connection *con) if (con->retries++ > MAX_CONNECT_RETRIES) return; - if (nodeid_to_addr(con->nodeid, NULL, (struct sockaddr *)&rem_addr)) { + if (nodeid_to_addr(con->nodeid, NULL, (struct sockaddr *)&rem_addr, + con->try_new_addr)) { log_print("no address for nodeid %d", con->nodeid); return; } @@ -1016,6 +1046,14 @@ static void sctp_init_assoc(struct connection *con) iov[0].iov_base = page_address(e->page)+offset; iov[0].iov_len = len; + if (rem_addr.ss_family == AF_INET) { + struct sockaddr_in *sin = (struct sockaddr_in *)&rem_addr; + log_print("Trying to connect to %pI4", &sin->sin_addr.s_addr); + } else { + struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&rem_addr; + log_print("Trying to connect to %pI6", &sin6->sin6_addr); + } + cmsg = CMSG_FIRSTHDR(&outmessage); cmsg->cmsg_level = IPPROTO_SCTP; cmsg->cmsg_type = SCTP_SNDRCV; @@ -1024,6 +1062,7 @@ static void sctp_init_assoc(struct connection *con) memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); sinfo->sinfo_ppid = cpu_to_le32(dlm_our_nodeid()); outmessage.msg_controllen = cmsg->cmsg_len; + sinfo->sinfo_flags |= SCTP_ADDR_OVER; ret = kernel_sendmsg(base_con->sock, &outmessage, iov, 1, len); if (ret < 0) { @@ -1076,7 +1115,7 @@ static void tcp_connect_to_sock(struct connection *con) goto out_err; memset(&saddr, 0, sizeof(saddr)); - result = nodeid_to_addr(con->nodeid, &saddr, NULL); + result = nodeid_to_addr(con->nodeid, &saddr, NULL, false); if (result < 0) { log_print("no address for nodeid %d", con->nodeid); goto out_err;