/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. */ /* * Copyright (c) 2006 Oracle. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - 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. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * */ #include #include #include #include #include #include #include #include /* * When transmitting messages in rdsv3_send_xmit, we need to emerge from * time to time and briefly release the CPU. Otherwise the softlock watchdog * will kick our shin. * Also, it seems fairer to not let one busy connection stall all the * others. * * send_batch_count is the number of times we'll loop in send_xmit. Setting * it to 0 will restore the old behavior (where we looped until we had * drained the queue). */ static int send_batch_count = 64; extern void rdsv3_ib_send_unmap_rdma(void *ic, struct rdsv3_rdma_op *op); /* * Reset the send state. Caller must hold c_send_lock when calling here. */ void rdsv3_send_reset(struct rdsv3_connection *conn) { struct rdsv3_message *rm, *tmp; struct rdsv3_rdma_op *ro; RDSV3_DPRINTF4("rdsv3_send_reset", "Enter(conn: %p)", conn); if (conn->c_xmit_rm) { rm = conn->c_xmit_rm; ro = rm->m_rdma_op; if (ro && ro->r_mapped) { RDSV3_DPRINTF2("rdsv3_send_reset", "rm %p mflg 0x%x map %d mihdl %p sgl %p", rm, rm->m_flags, ro->r_mapped, ro->r_rdma_sg[0].mihdl, ro->r_rdma_sg[0].swr.wr_sgl); rdsv3_ib_send_unmap_rdma(conn->c_transport_data, ro); } /* * Tell the user the RDMA op is no longer mapped by the * transport. This isn't entirely true (it's flushed out * independently) but as the connection is down, there's * no ongoing RDMA to/from that memory */ rdsv3_message_unmapped(conn->c_xmit_rm); rdsv3_message_put(conn->c_xmit_rm); conn->c_xmit_rm = NULL; } conn->c_xmit_sg = 0; conn->c_xmit_hdr_off = 0; conn->c_xmit_data_off = 0; conn->c_xmit_rdma_sent = 0; conn->c_map_queued = 0; conn->c_unacked_packets = rdsv3_sysctl_max_unacked_packets; conn->c_unacked_bytes = rdsv3_sysctl_max_unacked_bytes; /* Mark messages as retransmissions, and move them to the send q */ mutex_enter(&conn->c_lock); RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_retrans, m_conn_item) { set_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags); set_bit(RDSV3_MSG_RETRANSMITTED, &rm->m_flags); if (rm->m_rdma_op && rm->m_rdma_op->r_mapped) { RDSV3_DPRINTF4("_send_reset", "RT rm %p mflg 0x%x sgl %p", rm, rm->m_flags, rm->m_rdma_op->r_rdma_sg[0].swr.wr_sgl); } } list_move_tail(&conn->c_send_queue, &conn->c_retrans); mutex_exit(&conn->c_lock); RDSV3_DPRINTF4("rdsv3_send_reset", "Return(conn: %p)", conn); } /* * We're making the concious trade-off here to only send one message * down the connection at a time. * Pro: * - tx queueing is a simple fifo list * - reassembly is optional and easily done by transports per conn * - no per flow rx lookup at all, straight to the socket * - less per-frag memory and wire overhead * Con: * - queued acks can be delayed behind large messages * Depends: * - small message latency is higher behind queued large messages * - large message latency isn't starved by intervening small sends */ int rdsv3_send_xmit(struct rdsv3_connection *conn) { struct rdsv3_message *rm; unsigned int tmp; unsigned int send_quota = send_batch_count; struct rdsv3_scatterlist *sg; int ret = 0; int was_empty = 0; list_t to_be_dropped; RDSV3_DPRINTF4("rdsv3_send_xmit", "Enter(conn: %p)", conn); list_create(&to_be_dropped, sizeof (struct rdsv3_message), offsetof(struct rdsv3_message, m_conn_item)); /* * sendmsg calls here after having queued its message on the send * queue. We only have one task feeding the connection at a time. If * another thread is already feeding the queue then we back off. This * avoids blocking the caller and trading per-connection data between * caches per message. * * The sem holder will issue a retry if they notice that someone queued * a message after they stopped walking the send queue but before they * dropped the sem. */ if (!mutex_tryenter(&conn->c_send_lock)) { RDSV3_DPRINTF4("rdsv3_send_xmit", "Another thread running(conn: %p)", conn); rdsv3_stats_inc(s_send_sem_contention); ret = -ENOMEM; goto out; } if (conn->c_trans->xmit_prepare) conn->c_trans->xmit_prepare(conn); /* * spin trying to push headers and data down the connection until * the connection doens't make forward progress. */ while (--send_quota) { /* * See if need to send a congestion map update if we're * between sending messages. The send_sem protects our sole * use of c_map_offset and _bytes. * Note this is used only by transports that define a special * xmit_cong_map function. For all others, we create allocate * a cong_map message and treat it just like any other send. */ if (conn->c_map_bytes) { ret = conn->c_trans->xmit_cong_map(conn, conn->c_lcong, conn->c_map_offset); if (ret <= 0) break; conn->c_map_offset += ret; conn->c_map_bytes -= ret; if (conn->c_map_bytes) continue; } /* * If we're done sending the current message, clear the * offset and S/G temporaries. */ rm = conn->c_xmit_rm; if (rm != NULL && conn->c_xmit_hdr_off == sizeof (struct rdsv3_header) && conn->c_xmit_sg == rm->m_nents) { conn->c_xmit_rm = NULL; conn->c_xmit_sg = 0; conn->c_xmit_hdr_off = 0; conn->c_xmit_data_off = 0; conn->c_xmit_rdma_sent = 0; /* Release the reference to the previous message. */ rdsv3_message_put(rm); rm = NULL; } /* If we're asked to send a cong map update, do so. */ if (rm == NULL && test_and_clear_bit(0, &conn->c_map_queued)) { if (conn->c_trans->xmit_cong_map != NULL) { conn->c_map_offset = 0; conn->c_map_bytes = sizeof (struct rdsv3_header) + RDSV3_CONG_MAP_BYTES; continue; } rm = rdsv3_cong_update_alloc(conn); if (IS_ERR(rm)) { ret = PTR_ERR(rm); break; } conn->c_xmit_rm = rm; } /* * Grab the next message from the send queue, if there is one. * * c_xmit_rm holds a ref while we're sending this message down * the connction. We can use this ref while holding the * send_sem.. rdsv3_send_reset() is serialized with it. */ if (rm == NULL) { unsigned int len; mutex_enter(&conn->c_lock); if (!list_is_empty(&conn->c_send_queue)) { rm = list_remove_head(&conn->c_send_queue); rdsv3_message_addref(rm); /* * Move the message from the send queue to * the retransmit * list right away. */ list_insert_tail(&conn->c_retrans, rm); } mutex_exit(&conn->c_lock); if (rm == NULL) { was_empty = 1; break; } /* * Unfortunately, the way Infiniband deals with * RDMA to a bad MR key is by moving the entire * queue pair to error state. We cold possibly * recover from that, but right now we drop the * connection. * Therefore, we never retransmit messages with * RDMA ops. */ if (rm->m_rdma_op && test_bit(RDSV3_MSG_RETRANSMITTED, &rm->m_flags)) { mutex_enter(&conn->c_lock); if (test_and_clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags)) list_remove_node(&rm->m_conn_item); list_insert_tail(&to_be_dropped, rm); mutex_exit(&conn->c_lock); rdsv3_message_put(rm); continue; } /* Require an ACK every once in a while */ len = ntohl(rm->m_inc.i_hdr.h_len); if (conn->c_unacked_packets == 0 || conn->c_unacked_bytes < len) { set_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags); conn->c_unacked_packets = rdsv3_sysctl_max_unacked_packets; conn->c_unacked_bytes = rdsv3_sysctl_max_unacked_bytes; rdsv3_stats_inc(s_send_ack_required); } else { conn->c_unacked_bytes -= len; conn->c_unacked_packets--; } conn->c_xmit_rm = rm; } /* * Try and send an rdma message. Let's see if we can * keep this simple and require that the transport either * send the whole rdma or none of it. */ if (rm->m_rdma_op && !conn->c_xmit_rdma_sent) { ret = conn->c_trans->xmit_rdma(conn, rm->m_rdma_op); if (ret) break; conn->c_xmit_rdma_sent = 1; /* * The transport owns the mapped memory for now. * You can't unmap it while it's on the send queue */ set_bit(RDSV3_MSG_MAPPED, &rm->m_flags); } if (conn->c_xmit_hdr_off < sizeof (struct rdsv3_header) || conn->c_xmit_sg < rm->m_nents) { ret = conn->c_trans->xmit(conn, rm, conn->c_xmit_hdr_off, conn->c_xmit_sg, conn->c_xmit_data_off); if (ret <= 0) break; if (conn->c_xmit_hdr_off < sizeof (struct rdsv3_header)) { tmp = min(ret, sizeof (struct rdsv3_header) - conn->c_xmit_hdr_off); conn->c_xmit_hdr_off += tmp; ret -= tmp; } sg = &rm->m_sg[conn->c_xmit_sg]; while (ret) { tmp = min(ret, rdsv3_sg_len(sg) - conn->c_xmit_data_off); conn->c_xmit_data_off += tmp; ret -= tmp; if (conn->c_xmit_data_off == rdsv3_sg_len(sg)) { conn->c_xmit_data_off = 0; sg++; conn->c_xmit_sg++; ASSERT(!(ret != 0 && conn->c_xmit_sg == rm->m_nents)); } } } } /* Nuke any messages we decided not to retransmit. */ if (!list_is_empty(&to_be_dropped)) rdsv3_send_remove_from_sock(&to_be_dropped, RDSV3_RDMA_DROPPED); if (conn->c_trans->xmit_complete) conn->c_trans->xmit_complete(conn); /* * We might be racing with another sender who queued a message but * backed off on noticing that we held the c_send_lock. If we check * for queued messages after dropping the sem then either we'll * see the queued message or the queuer will get the sem. If we * notice the queued message then we trigger an immediate retry. * * We need to be careful only to do this when we stopped processing * the send queue because it was empty. It's the only way we * stop processing the loop when the transport hasn't taken * responsibility for forward progress. */ mutex_exit(&conn->c_send_lock); if (conn->c_map_bytes || (send_quota == 0 && !was_empty)) { /* * We exhausted the send quota, but there's work left to * do. Return and (re-)schedule the send worker. */ ret = -EAGAIN; } if (ret == 0 && was_empty) { /* * A simple bit test would be way faster than taking the * spin lock */ mutex_enter(&conn->c_lock); if (!list_is_empty(&conn->c_send_queue)) { rdsv3_stats_inc(s_send_sem_queue_raced); ret = -EAGAIN; } mutex_exit(&conn->c_lock); } out: RDSV3_DPRINTF4("rdsv3_send_xmit", "Return(conn: %p, ret: %d)", conn, ret); return (ret); } static void rdsv3_send_sndbuf_remove(struct rdsv3_sock *rs, struct rdsv3_message *rm) { uint32_t len = ntohl(rm->m_inc.i_hdr.h_len); ASSERT(mutex_owned(&rs->rs_lock)); ASSERT(rs->rs_snd_bytes >= len); rs->rs_snd_bytes -= len; if (rs->rs_snd_bytes == 0) rdsv3_stats_inc(s_send_queue_empty); } static inline int rdsv3_send_is_acked(struct rdsv3_message *rm, uint64_t ack, is_acked_func is_acked) { if (is_acked) return (is_acked(rm, ack)); return (ntohll(rm->m_inc.i_hdr.h_sequence) <= ack); } /* * Returns true if there are no messages on the send and retransmit queues * which have a sequence number greater than or equal to the given sequence * number. */ int rdsv3_send_acked_before(struct rdsv3_connection *conn, uint64_t seq) { struct rdsv3_message *rm; int ret = 1; RDSV3_DPRINTF4("rdsv3_send_acked_before", "Enter(conn: %p)", conn); mutex_enter(&conn->c_lock); /* XXX - original code spits out warning */ rm = list_head(&conn->c_retrans); if (ntohll(rm->m_inc.i_hdr.h_sequence) < seq) ret = 0; /* XXX - original code spits out warning */ rm = list_head(&conn->c_send_queue); if (ntohll(rm->m_inc.i_hdr.h_sequence) < seq) ret = 0; mutex_exit(&conn->c_lock); RDSV3_DPRINTF4("rdsv3_send_acked_before", "Return(conn: %p)", conn); return (ret); } /* * This is pretty similar to what happens below in the ACK * handling code - except that we call here as soon as we get * the IB send completion on the RDMA op and the accompanying * message. */ void rdsv3_rdma_send_complete(struct rdsv3_message *rm, int status) { struct rdsv3_sock *rs = NULL; struct rdsv3_rdma_op *ro; struct rdsv3_notifier *notifier; RDSV3_DPRINTF4("rdsv3_rdma_send_complete", "Enter(rm: %p)", rm); mutex_enter(&rm->m_rs_lock); ro = rm->m_rdma_op; if (test_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags) && ro && ro->r_notify && ro->r_notifier) { notifier = ro->r_notifier; rs = rm->m_rs; rdsv3_sk_sock_hold(rdsv3_rs_to_sk(rs)); notifier->n_status = status; mutex_enter(&rs->rs_lock); list_insert_tail(&rs->rs_notify_queue, notifier); mutex_exit(&rs->rs_lock); ro->r_notifier = NULL; } mutex_exit(&rm->m_rs_lock); if (rs) { rdsv3_wake_sk_sleep(rs); rdsv3_sk_sock_put(rdsv3_rs_to_sk(rs)); } RDSV3_DPRINTF4("rdsv3_rdma_send_complete", "Return(rm: %p)", rm); } /* * This is the same as rdsv3_rdma_send_complete except we * don't do any locking - we have all the ingredients (message, * socket, socket lock) and can just move the notifier. */ static inline void __rdsv3_rdma_send_complete(struct rdsv3_sock *rs, struct rdsv3_message *rm, int status) { struct rdsv3_rdma_op *ro; void *ic; RDSV3_DPRINTF4("__rdsv3_rdma_send_complete", "Enter(rs: %p, rm: %p)", rs, rm); ro = rm->m_rdma_op; if (ro && ro->r_notify && ro->r_notifier) { ro->r_notifier->n_status = status; list_insert_tail(&rs->rs_notify_queue, ro->r_notifier); ro->r_notifier = NULL; } /* No need to wake the app - caller does this */ } /* * This is called from the IB send completion when we detect * a RDMA operation that failed with remote access error. * So speed is not an issue here. */ struct rdsv3_message * rdsv3_send_get_message(struct rdsv3_connection *conn, struct rdsv3_rdma_op *op) { struct rdsv3_message *rm, *tmp, *found = NULL; RDSV3_DPRINTF4("rdsv3_send_get_message", "Enter(conn: %p)", conn); mutex_enter(&conn->c_lock); RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_retrans, m_conn_item) { if (rm->m_rdma_op == op) { atomic_add_32(&rm->m_refcount, 1); found = rm; goto out; } } RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_send_queue, m_conn_item) { if (rm->m_rdma_op == op) { atomic_add_32(&rm->m_refcount, 1); found = rm; break; } } out: mutex_exit(&conn->c_lock); return (found); } /* * This removes messages from the socket's list if they're on it. The list * argument must be private to the caller, we must be able to modify it * without locks. The messages must have a reference held for their * position on the list. This function will drop that reference after * removing the messages from the 'messages' list regardless of if it found * the messages on the socket list or not. */ void rdsv3_send_remove_from_sock(struct list *messages, int status) { struct rdsv3_sock *rs = NULL; struct rdsv3_message *rm; RDSV3_DPRINTF4("rdsv3_send_remove_from_sock", "Enter"); while (!list_is_empty(messages)) { int was_on_sock = 0; rm = list_remove_head(messages); /* * If we see this flag cleared then we're *sure* that someone * else beat us to removing it from the sock. If we race * with their flag update we'll get the lock and then really * see that the flag has been cleared. * * The message spinlock makes sure nobody clears rm->m_rs * while we're messing with it. It does not prevent the * message from being removed from the socket, though. */ mutex_enter(&rm->m_rs_lock); if (!test_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags)) goto unlock_and_drop; if (rs != rm->m_rs) { if (rs) { rdsv3_wake_sk_sleep(rs); rdsv3_sk_sock_put(rdsv3_rs_to_sk(rs)); } rs = rm->m_rs; rdsv3_sk_sock_hold(rdsv3_rs_to_sk(rs)); } mutex_enter(&rs->rs_lock); if (test_and_clear_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags)) { struct rdsv3_rdma_op *ro = rm->m_rdma_op; struct rdsv3_notifier *notifier; list_remove_node(&rm->m_sock_item); rdsv3_send_sndbuf_remove(rs, rm); if (ro && ro->r_notifier && (status || ro->r_notify)) { notifier = ro->r_notifier; list_insert_tail(&rs->rs_notify_queue, notifier); if (!notifier->n_status) notifier->n_status = status; rm->m_rdma_op->r_notifier = NULL; } was_on_sock = 1; rm->m_rs = NULL; } mutex_exit(&rs->rs_lock); unlock_and_drop: mutex_exit(&rm->m_rs_lock); rdsv3_message_put(rm); if (was_on_sock) rdsv3_message_put(rm); } if (rs) { rdsv3_wake_sk_sleep(rs); rdsv3_sk_sock_put(rdsv3_rs_to_sk(rs)); } RDSV3_DPRINTF4("rdsv3_send_remove_from_sock", "Return"); } /* * Transports call here when they've determined that the receiver queued * messages up to, and including, the given sequence number. Messages are * moved to the retrans queue when rdsv3_send_xmit picks them off the send * queue. This means that in the TCP case, the message may not have been * assigned the m_ack_seq yet - but that's fine as long as tcp_is_acked * checks the RDSV3_MSG_HAS_ACK_SEQ bit. * * XXX It's not clear to me how this is safely serialized with socket * destruction. Maybe it should bail if it sees SOCK_DEAD. */ void rdsv3_send_drop_acked(struct rdsv3_connection *conn, uint64_t ack, is_acked_func is_acked) { struct rdsv3_message *rm, *tmp; list_t list; RDSV3_DPRINTF4("rdsv3_send_drop_acked", "Enter(conn: %p)", conn); list_create(&list, sizeof (struct rdsv3_message), offsetof(struct rdsv3_message, m_conn_item)); mutex_enter(&conn->c_lock); RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &conn->c_retrans, m_conn_item) { if (!rdsv3_send_is_acked(rm, ack, is_acked)) break; list_remove_node(&rm->m_conn_item); list_insert_tail(&list, rm); clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags); } #if 0 XXX /* order flag updates with spin locks */ if (!list_is_empty(&list)) smp_mb__after_clear_bit(); #endif mutex_exit(&conn->c_lock); /* now remove the messages from the sock list as needed */ rdsv3_send_remove_from_sock(&list, RDSV3_RDMA_SUCCESS); RDSV3_DPRINTF4("rdsv3_send_drop_acked", "Return(conn: %p)", conn); } void rdsv3_send_drop_to(struct rdsv3_sock *rs, struct sockaddr_in *dest) { struct rdsv3_message *rm, *tmp; struct rdsv3_connection *conn; list_t list; int wake = 0; RDSV3_DPRINTF4("rdsv3_send_drop_to", "Enter(rs: %p)", rs); list_create(&list, sizeof (struct rdsv3_message), offsetof(struct rdsv3_message, m_sock_item)); /* get all the messages we're dropping under the rs lock */ mutex_enter(&rs->rs_lock); RDSV3_FOR_EACH_LIST_NODE_SAFE(rm, tmp, &rs->rs_send_queue, m_sock_item) { if (dest && (dest->sin_addr.s_addr != rm->m_daddr || dest->sin_port != rm->m_inc.i_hdr.h_dport)) continue; wake = 1; list_remove(&rs->rs_send_queue, rm); list_insert_tail(&list, rm); rdsv3_send_sndbuf_remove(rs, rm); clear_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags); } mutex_exit(&rs->rs_lock); conn = NULL; /* now remove the messages from the conn list as needed */ RDSV3_FOR_EACH_LIST_NODE(rm, &list, m_sock_item) { /* * We do this here rather than in the loop above, so that * we don't have to nest m_rs_lock under rs->rs_lock */ mutex_enter(&rm->m_rs_lock); /* If this is a RDMA operation, notify the app. */ __rdsv3_rdma_send_complete(rs, rm, RDSV3_RDMA_CANCELED); rm->m_rs = NULL; mutex_exit(&rm->m_rs_lock); /* * If we see this flag cleared then we're *sure* that someone * else beat us to removing it from the conn. If we race * with their flag update we'll get the lock and then really * see that the flag has been cleared. */ if (!test_bit(RDSV3_MSG_ON_CONN, &rm->m_flags)) continue; if (conn != rm->m_inc.i_conn) { if (conn) mutex_exit(&conn->c_lock); conn = rm->m_inc.i_conn; mutex_enter(&conn->c_lock); } if (test_and_clear_bit(RDSV3_MSG_ON_CONN, &rm->m_flags)) { list_remove_node(&rm->m_conn_item); rdsv3_message_put(rm); } } if (conn) mutex_exit(&conn->c_lock); if (wake) rdsv3_wake_sk_sleep(rs); while (!list_is_empty(&list)) { rm = list_remove_head(&list); rdsv3_message_wait(rm); rdsv3_message_put(rm); } RDSV3_DPRINTF4("rdsv3_send_drop_to", "Return(rs: %p)", rs); } /* * we only want this to fire once so we use the callers 'queued'. It's * possible that another thread can race with us and remove the * message from the flow with RDSV3_CANCEL_SENT_TO. */ static int rdsv3_send_queue_rm(struct rdsv3_sock *rs, struct rdsv3_connection *conn, struct rdsv3_message *rm, uint16_be_t sport, uint16_be_t dport, int *queued) { uint32_t len; RDSV3_DPRINTF4("rdsv3_send_queue_rm", "Enter(rs: %p, rm: %p)", rs, rm); if (*queued) goto out; len = ntohl(rm->m_inc.i_hdr.h_len); /* * this is the only place which holds both the socket's rs_lock * and the connection's c_lock */ mutex_enter(&rs->rs_lock); /* * If there is a little space in sndbuf, we don't queue anything, * and userspace gets -EAGAIN. But poll() indicates there's send * room. This can lead to bad behavior (spinning) if snd_bytes isn't * freed up by incoming acks. So we check the *old* value of * rs_snd_bytes here to allow the last msg to exceed the buffer, * and poll() now knows no more data can be sent. */ if (rs->rs_snd_bytes < rdsv3_sk_sndbuf(rs)) { rs->rs_snd_bytes += len; /* * let recv side know we are close to send space exhaustion. * This is probably not the optimal way to do it, as this * means we set the flag on *all* messages as soon as our * throughput hits a certain threshold. */ if (rs->rs_snd_bytes >= rdsv3_sk_sndbuf(rs) / 2) set_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags); list_insert_tail(&rs->rs_send_queue, rm); set_bit(RDSV3_MSG_ON_SOCK, &rm->m_flags); rdsv3_message_addref(rm); rm->m_rs = rs; /* * The code ordering is a little weird, but we're * trying to minimize the time we hold c_lock */ rdsv3_message_populate_header(&rm->m_inc.i_hdr, sport, dport, 0); rm->m_inc.i_conn = conn; rdsv3_message_addref(rm); /* XXX - called twice */ mutex_enter(&conn->c_lock); rm->m_inc.i_hdr.h_sequence = htonll(conn->c_next_tx_seq++); list_insert_tail(&conn->c_send_queue, rm); set_bit(RDSV3_MSG_ON_CONN, &rm->m_flags); mutex_exit(&conn->c_lock); RDSV3_DPRINTF5("rdsv3_send_queue_rm", "queued msg %p len %d, rs %p bytes %d seq %llu", rm, len, rs, rs->rs_snd_bytes, (unsigned long long)ntohll( rm->m_inc.i_hdr.h_sequence)); *queued = 1; } mutex_exit(&rs->rs_lock); RDSV3_DPRINTF4("rdsv3_send_queue_rm", "Return(rs: %p)", rs); out: return (*queued); } static int rdsv3_cmsg_send(struct rdsv3_sock *rs, struct rdsv3_message *rm, struct msghdr *msg, int *allocated_mr) { struct cmsghdr *cmsg; int ret = 0; RDSV3_DPRINTF4("rdsv3_cmsg_send", "Enter(rs: %p)", rs); for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { if (cmsg->cmsg_level != SOL_RDS) continue; RDSV3_DPRINTF4("rdsv3_cmsg_send", "cmsg(%p, %p) type %d", cmsg, rm, cmsg->cmsg_type); /* * As a side effect, RDMA_DEST and RDMA_MAP will set * rm->m_rdma_cookie and rm->m_rdma_mr. */ switch (cmsg->cmsg_type) { case RDSV3_CMSG_RDMA_ARGS: ret = rdsv3_cmsg_rdma_args(rs, rm, cmsg); break; case RDSV3_CMSG_RDMA_DEST: ret = rdsv3_cmsg_rdma_dest(rs, rm, cmsg); break; case RDSV3_CMSG_RDMA_MAP: ret = rdsv3_cmsg_rdma_map(rs, rm, cmsg); if (ret) *allocated_mr = 1; break; default: return (-EINVAL); } if (ret) break; } RDSV3_DPRINTF4("rdsv3_cmsg_send", "Return(rs: %p)", rs); return (ret); } int rdsv3_sendmsg(struct rdsv3_sock *rs, uio_t *uio, struct nmsghdr *msg, size_t payload_len) { struct rsock *sk = rdsv3_rs_to_sk(rs); struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name; uint32_be_t daddr; uint16_be_t dport; struct rdsv3_message *rm = NULL; struct rdsv3_connection *conn; int ret = 0; int queued = 0, allocated_mr = 0; int nonblock = msg->msg_flags & MSG_DONTWAIT; long timeo = rdsv3_sndtimeo(sk, nonblock); RDSV3_DPRINTF4("rdsv3_sendmsg", "Enter(rs: %p)", rs); if (msg->msg_namelen) { /* XXX fail non-unicast destination IPs? */ if (msg->msg_namelen < sizeof (*usin) || usin->sin_family != AF_INET_OFFLOAD) { ret = -EINVAL; RDSV3_DPRINTF2("rdsv3_sendmsg", "returning: %d", -ret); goto out; } daddr = usin->sin_addr.s_addr; dport = usin->sin_port; } else { /* We only care about consistency with ->connect() */ mutex_enter(&sk->sk_lock); daddr = rs->rs_conn_addr; dport = rs->rs_conn_port; mutex_exit(&sk->sk_lock); } /* racing with another thread binding seems ok here */ if (daddr == 0 || rs->rs_bound_addr == 0) { ret = -ENOTCONN; /* XXX not a great errno */ RDSV3_DPRINTF2("rdsv3_sendmsg", "returning: %d", -ret); goto out; } rm = rdsv3_message_copy_from_user(uio, payload_len); if (IS_ERR(rm)) { ret = PTR_ERR(rm); RDSV3_DPRINTF2("rdsv3_sendmsg", "rdsv3_message_copy_from_user failed %d", -ret); rm = NULL; goto out; } rm->m_daddr = daddr; /* Parse any control messages the user may have included. */ ret = rdsv3_cmsg_send(rs, rm, msg, &allocated_mr); if (ret) { RDSV3_DPRINTF2("rdsv3_sendmsg", "rdsv3_cmsg_send(rs: %p rm: %p msg: %p) returned: %d", rs, rm, msg, ret); goto out; } /* * rdsv3_conn_create has a spinlock that runs with IRQ off. * Caching the conn in the socket helps a lot. */ mutex_enter(&rs->rs_conn_lock); if (rs->rs_conn && rs->rs_conn->c_faddr == daddr) { conn = rs->rs_conn; } else { conn = rdsv3_conn_create_outgoing(rs->rs_bound_addr, daddr, rs->rs_transport, KM_NOSLEEP); if (IS_ERR(conn)) { mutex_exit(&rs->rs_conn_lock); ret = PTR_ERR(conn); RDSV3_DPRINTF2("rdsv3_sendmsg", "rdsv3_conn_create_outgoing failed %d", -ret); goto out; } rs->rs_conn = conn; } mutex_exit(&rs->rs_conn_lock); if ((rm->m_rdma_cookie || rm->m_rdma_op) && conn->c_trans->xmit_rdma == NULL) { RDSV3_DPRINTF2("rdsv3_sendmsg", "rdma_op %p conn xmit_rdma %p", rm->m_rdma_op, conn->c_trans->xmit_rdma); ret = -EOPNOTSUPP; goto out; } /* * If the connection is down, trigger a connect. We may * have scheduled a delayed reconnect however - in this case * we should not interfere. */ if (rdsv3_conn_state(conn) == RDSV3_CONN_DOWN && !test_and_set_bit(RDSV3_RECONNECT_PENDING, &conn->c_flags)) rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_conn_w, 0); ret = rdsv3_cong_wait(conn->c_fcong, dport, nonblock, rs); if (ret) { mutex_enter(&rdsv3_poll_waitq.waitq_mutex); rs->rs_seen_congestion = 1; cv_signal(&rdsv3_poll_waitq.waitq_cv); mutex_exit(&rdsv3_poll_waitq.waitq_mutex); RDSV3_DPRINTF2("rdsv3_sendmsg", "rdsv3_cong_wait (dport: %d) returned: %d", dport, ret); goto out; } (void) rdsv3_send_queue_rm(rs, conn, rm, rs->rs_bound_port, dport, &queued); if (!queued) { /* rdsv3_stats_inc(s_send_queue_full); */ /* XXX make sure this is reasonable */ if (payload_len > rdsv3_sk_sndbuf(rs)) { ret = -EMSGSIZE; RDSV3_DPRINTF2("rdsv3_sendmsg", "msgsize(%d) too big, returning: %d", payload_len, -ret); goto out; } if (nonblock) { ret = -EAGAIN; RDSV3_DPRINTF3("rdsv3_sendmsg", "send queue full (%d), returning: %d", payload_len, -ret); goto out; } #if 0 ret = rdsv3_wait_sig(sk->sk_sleep, (rdsv3_send_queue_rm(rs, conn, rm, rs->rs_bound_port, dport, &queued))); if (ret == 0) { /* signal/timeout pending */ RDSV3_DPRINTF2("rdsv3_sendmsg", "woke due to signal: %d", ret); ret = -ERESTART; goto out; } #else mutex_enter(&sk->sk_sleep->waitq_mutex); sk->sk_sleep->waitq_waiters++; while (!rdsv3_send_queue_rm(rs, conn, rm, rs->rs_bound_port, dport, &queued)) { ret = cv_wait_sig(&sk->sk_sleep->waitq_cv, &sk->sk_sleep->waitq_mutex); if (ret == 0) { /* signal/timeout pending */ RDSV3_DPRINTF2("rdsv3_sendmsg", "woke due to signal: %d", ret); ret = -ERESTART; sk->sk_sleep->waitq_waiters--; mutex_exit(&sk->sk_sleep->waitq_mutex); goto out; } } sk->sk_sleep->waitq_waiters--; mutex_exit(&sk->sk_sleep->waitq_mutex); #endif RDSV3_DPRINTF5("rdsv3_sendmsg", "sendmsg woke queued %d", queued); ASSERT(queued); ret = 0; } /* * By now we've committed to the send. We reuse rdsv3_send_worker() * to retry sends in the rds thread if the transport asks us to. */ rdsv3_stats_inc(s_send_queued); if (!test_bit(RDSV3_LL_SEND_FULL, &conn->c_flags)) rdsv3_send_worker(&conn->c_send_w.work); rdsv3_message_put(rm); RDSV3_DPRINTF4("rdsv3_sendmsg", "Return(rs: %p, len: %d)", rs, payload_len); return (payload_len); out: /* * If the user included a RDMA_MAP cmsg, we allocated a MR on the fly. * If the sendmsg goes through, we keep the MR. If it fails with EAGAIN * or in any other way, we need to destroy the MR again */ if (allocated_mr) rdsv3_rdma_unuse(rs, rdsv3_rdma_cookie_key(rm->m_rdma_cookie), 1); if (rm) rdsv3_message_put(rm); return (ret); } /* * Reply to a ping packet. */ int rdsv3_send_pong(struct rdsv3_connection *conn, uint16_be_t dport) { struct rdsv3_message *rm; int ret = 0; RDSV3_DPRINTF4("rdsv3_send_pong", "Enter(conn: %p)", conn); rm = rdsv3_message_alloc(0, KM_NOSLEEP); if (rm == NULL) { ret = -ENOMEM; goto out; } rm->m_daddr = conn->c_faddr; /* * If the connection is down, trigger a connect. We may * have scheduled a delayed reconnect however - in this case * we should not interfere. */ if (rdsv3_conn_state(conn) == RDSV3_CONN_DOWN && !test_and_set_bit(RDSV3_RECONNECT_PENDING, &conn->c_flags)) rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_conn_w, 0); ret = rdsv3_cong_wait(conn->c_fcong, dport, 1, NULL); if (ret) goto out; mutex_enter(&conn->c_lock); list_insert_tail(&conn->c_send_queue, rm); set_bit(RDSV3_MSG_ON_CONN, &rm->m_flags); rdsv3_message_addref(rm); rm->m_inc.i_conn = conn; rdsv3_message_populate_header(&rm->m_inc.i_hdr, 0, dport, conn->c_next_tx_seq); conn->c_next_tx_seq++; mutex_exit(&conn->c_lock); rdsv3_stats_inc(s_send_queued); rdsv3_stats_inc(s_send_pong); rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_send_w, 0); rdsv3_message_put(rm); RDSV3_DPRINTF4("rdsv3_send_pong", "Return(conn: %p)", conn); return (0); out: if (rm) rdsv3_message_put(rm); return (ret); }