| /* |
| * 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 <linux/kernel.h> |
| #include <net/sock.h> |
| #include <linux/in.h> |
| |
| #include "rds.h" |
| #include "rdma.h" |
| |
| void rds_inc_init(struct rds_incoming *inc, struct rds_connection *conn, |
| __be32 saddr) |
| { |
| atomic_set(&inc->i_refcount, 1); |
| INIT_LIST_HEAD(&inc->i_item); |
| inc->i_conn = conn; |
| inc->i_saddr = saddr; |
| inc->i_rdma_cookie = 0; |
| } |
| EXPORT_SYMBOL_GPL(rds_inc_init); |
| |
| void rds_inc_addref(struct rds_incoming *inc) |
| { |
| rdsdebug("addref inc %p ref %d\n", inc, atomic_read(&inc->i_refcount)); |
| atomic_inc(&inc->i_refcount); |
| } |
| EXPORT_SYMBOL_GPL(rds_inc_addref); |
| |
| void rds_inc_put(struct rds_incoming *inc) |
| { |
| rdsdebug("put inc %p ref %d\n", inc, atomic_read(&inc->i_refcount)); |
| if (atomic_dec_and_test(&inc->i_refcount)) { |
| BUG_ON(!list_empty(&inc->i_item)); |
| |
| inc->i_conn->c_trans->inc_free(inc); |
| } |
| } |
| EXPORT_SYMBOL_GPL(rds_inc_put); |
| |
| static void rds_recv_rcvbuf_delta(struct rds_sock *rs, struct sock *sk, |
| struct rds_cong_map *map, |
| int delta, __be16 port) |
| { |
| int now_congested; |
| |
| if (delta == 0) |
| return; |
| |
| rs->rs_rcv_bytes += delta; |
| now_congested = rs->rs_rcv_bytes > rds_sk_rcvbuf(rs); |
| |
| rdsdebug("rs %p (%pI4:%u) recv bytes %d buf %d " |
| "now_cong %d delta %d\n", |
| rs, &rs->rs_bound_addr, |
| ntohs(rs->rs_bound_port), rs->rs_rcv_bytes, |
| rds_sk_rcvbuf(rs), now_congested, delta); |
| |
| /* wasn't -> am congested */ |
| if (!rs->rs_congested && now_congested) { |
| rs->rs_congested = 1; |
| rds_cong_set_bit(map, port); |
| rds_cong_queue_updates(map); |
| } |
| /* was -> aren't congested */ |
| /* Require more free space before reporting uncongested to prevent |
| bouncing cong/uncong state too often */ |
| else if (rs->rs_congested && (rs->rs_rcv_bytes < (rds_sk_rcvbuf(rs)/2))) { |
| rs->rs_congested = 0; |
| rds_cong_clear_bit(map, port); |
| rds_cong_queue_updates(map); |
| } |
| |
| /* do nothing if no change in cong state */ |
| } |
| |
| /* |
| * Process all extension headers that come with this message. |
| */ |
| static void rds_recv_incoming_exthdrs(struct rds_incoming *inc, struct rds_sock *rs) |
| { |
| struct rds_header *hdr = &inc->i_hdr; |
| unsigned int pos = 0, type, len; |
| union { |
| struct rds_ext_header_version version; |
| struct rds_ext_header_rdma rdma; |
| struct rds_ext_header_rdma_dest rdma_dest; |
| } buffer; |
| |
| while (1) { |
| len = sizeof(buffer); |
| type = rds_message_next_extension(hdr, &pos, &buffer, &len); |
| if (type == RDS_EXTHDR_NONE) |
| break; |
| /* Process extension header here */ |
| switch (type) { |
| case RDS_EXTHDR_RDMA: |
| rds_rdma_unuse(rs, be32_to_cpu(buffer.rdma.h_rdma_rkey), 0); |
| break; |
| |
| case RDS_EXTHDR_RDMA_DEST: |
| /* We ignore the size for now. We could stash it |
| * somewhere and use it for error checking. */ |
| inc->i_rdma_cookie = rds_rdma_make_cookie( |
| be32_to_cpu(buffer.rdma_dest.h_rdma_rkey), |
| be32_to_cpu(buffer.rdma_dest.h_rdma_offset)); |
| |
| break; |
| } |
| } |
| } |
| |
| /* |
| * The transport must make sure that this is serialized against other |
| * rx and conn reset on this specific conn. |
| * |
| * We currently assert that only one fragmented message will be sent |
| * down a connection at a time. This lets us reassemble in the conn |
| * instead of per-flow which means that we don't have to go digging through |
| * flows to tear down partial reassembly progress on conn failure and |
| * we save flow lookup and locking for each frag arrival. It does mean |
| * that small messages will wait behind large ones. Fragmenting at all |
| * is only to reduce the memory consumption of pre-posted buffers. |
| * |
| * The caller passes in saddr and daddr instead of us getting it from the |
| * conn. This lets loopback, who only has one conn for both directions, |
| * tell us which roles the addrs in the conn are playing for this message. |
| */ |
| void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr, |
| struct rds_incoming *inc, gfp_t gfp, enum km_type km) |
| { |
| struct rds_sock *rs = NULL; |
| struct sock *sk; |
| unsigned long flags; |
| |
| inc->i_conn = conn; |
| inc->i_rx_jiffies = jiffies; |
| |
| rdsdebug("conn %p next %llu inc %p seq %llu len %u sport %u dport %u " |
| "flags 0x%x rx_jiffies %lu\n", conn, |
| (unsigned long long)conn->c_next_rx_seq, |
| inc, |
| (unsigned long long)be64_to_cpu(inc->i_hdr.h_sequence), |
| be32_to_cpu(inc->i_hdr.h_len), |
| be16_to_cpu(inc->i_hdr.h_sport), |
| be16_to_cpu(inc->i_hdr.h_dport), |
| inc->i_hdr.h_flags, |
| inc->i_rx_jiffies); |
| |
| /* |
| * Sequence numbers should only increase. Messages get their |
| * sequence number as they're queued in a sending conn. They |
| * can be dropped, though, if the sending socket is closed before |
| * they hit the wire. So sequence numbers can skip forward |
| * under normal operation. They can also drop back in the conn |
| * failover case as previously sent messages are resent down the |
| * new instance of a conn. We drop those, otherwise we have |
| * to assume that the next valid seq does not come after a |
| * hole in the fragment stream. |
| * |
| * The headers don't give us a way to realize if fragments of |
| * a message have been dropped. We assume that frags that arrive |
| * to a flow are part of the current message on the flow that is |
| * being reassembled. This means that senders can't drop messages |
| * from the sending conn until all their frags are sent. |
| * |
| * XXX we could spend more on the wire to get more robust failure |
| * detection, arguably worth it to avoid data corruption. |
| */ |
| if (be64_to_cpu(inc->i_hdr.h_sequence) < conn->c_next_rx_seq |
| && (inc->i_hdr.h_flags & RDS_FLAG_RETRANSMITTED)) { |
| rds_stats_inc(s_recv_drop_old_seq); |
| goto out; |
| } |
| conn->c_next_rx_seq = be64_to_cpu(inc->i_hdr.h_sequence) + 1; |
| |
| if (rds_sysctl_ping_enable && inc->i_hdr.h_dport == 0) { |
| rds_stats_inc(s_recv_ping); |
| rds_send_pong(conn, inc->i_hdr.h_sport); |
| goto out; |
| } |
| |
| rs = rds_find_bound(daddr, inc->i_hdr.h_dport); |
| if (rs == NULL) { |
| rds_stats_inc(s_recv_drop_no_sock); |
| goto out; |
| } |
| |
| /* Process extension headers */ |
| rds_recv_incoming_exthdrs(inc, rs); |
| |
| /* We can be racing with rds_release() which marks the socket dead. */ |
| sk = rds_rs_to_sk(rs); |
| |
| /* serialize with rds_release -> sock_orphan */ |
| write_lock_irqsave(&rs->rs_recv_lock, flags); |
| if (!sock_flag(sk, SOCK_DEAD)) { |
| rdsdebug("adding inc %p to rs %p's recv queue\n", inc, rs); |
| rds_stats_inc(s_recv_queued); |
| rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong, |
| be32_to_cpu(inc->i_hdr.h_len), |
| inc->i_hdr.h_dport); |
| rds_inc_addref(inc); |
| list_add_tail(&inc->i_item, &rs->rs_recv_queue); |
| __rds_wake_sk_sleep(sk); |
| } else { |
| rds_stats_inc(s_recv_drop_dead_sock); |
| } |
| write_unlock_irqrestore(&rs->rs_recv_lock, flags); |
| |
| out: |
| if (rs) |
| rds_sock_put(rs); |
| } |
| EXPORT_SYMBOL_GPL(rds_recv_incoming); |
| |
| /* |
| * be very careful here. This is being called as the condition in |
| * wait_event_*() needs to cope with being called many times. |
| */ |
| static int rds_next_incoming(struct rds_sock *rs, struct rds_incoming **inc) |
| { |
| unsigned long flags; |
| |
| if (*inc == NULL) { |
| read_lock_irqsave(&rs->rs_recv_lock, flags); |
| if (!list_empty(&rs->rs_recv_queue)) { |
| *inc = list_entry(rs->rs_recv_queue.next, |
| struct rds_incoming, |
| i_item); |
| rds_inc_addref(*inc); |
| } |
| read_unlock_irqrestore(&rs->rs_recv_lock, flags); |
| } |
| |
| return *inc != NULL; |
| } |
| |
| static int rds_still_queued(struct rds_sock *rs, struct rds_incoming *inc, |
| int drop) |
| { |
| struct sock *sk = rds_rs_to_sk(rs); |
| int ret = 0; |
| unsigned long flags; |
| |
| write_lock_irqsave(&rs->rs_recv_lock, flags); |
| if (!list_empty(&inc->i_item)) { |
| ret = 1; |
| if (drop) { |
| /* XXX make sure this i_conn is reliable */ |
| rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong, |
| -be32_to_cpu(inc->i_hdr.h_len), |
| inc->i_hdr.h_dport); |
| list_del_init(&inc->i_item); |
| rds_inc_put(inc); |
| } |
| } |
| write_unlock_irqrestore(&rs->rs_recv_lock, flags); |
| |
| rdsdebug("inc %p rs %p still %d dropped %d\n", inc, rs, ret, drop); |
| return ret; |
| } |
| |
| /* |
| * Pull errors off the error queue. |
| * If msghdr is NULL, we will just purge the error queue. |
| */ |
| int rds_notify_queue_get(struct rds_sock *rs, struct msghdr *msghdr) |
| { |
| struct rds_notifier *notifier; |
| struct rds_rdma_notify cmsg = { 0 }; /* fill holes with zero */ |
| unsigned int count = 0, max_messages = ~0U; |
| unsigned long flags; |
| LIST_HEAD(copy); |
| int err = 0; |
| |
| |
| /* put_cmsg copies to user space and thus may sleep. We can't do this |
| * with rs_lock held, so first grab as many notifications as we can stuff |
| * in the user provided cmsg buffer. We don't try to copy more, to avoid |
| * losing notifications - except when the buffer is so small that it wouldn't |
| * even hold a single notification. Then we give him as much of this single |
| * msg as we can squeeze in, and set MSG_CTRUNC. |
| */ |
| if (msghdr) { |
| max_messages = msghdr->msg_controllen / CMSG_SPACE(sizeof(cmsg)); |
| if (!max_messages) |
| max_messages = 1; |
| } |
| |
| spin_lock_irqsave(&rs->rs_lock, flags); |
| while (!list_empty(&rs->rs_notify_queue) && count < max_messages) { |
| notifier = list_entry(rs->rs_notify_queue.next, |
| struct rds_notifier, n_list); |
| list_move(¬ifier->n_list, ©); |
| count++; |
| } |
| spin_unlock_irqrestore(&rs->rs_lock, flags); |
| |
| if (!count) |
| return 0; |
| |
| while (!list_empty(©)) { |
| notifier = list_entry(copy.next, struct rds_notifier, n_list); |
| |
| if (msghdr) { |
| cmsg.user_token = notifier->n_user_token; |
| cmsg.status = notifier->n_status; |
| |
| err = put_cmsg(msghdr, SOL_RDS, RDS_CMSG_RDMA_STATUS, |
| sizeof(cmsg), &cmsg); |
| if (err) |
| break; |
| } |
| |
| list_del_init(¬ifier->n_list); |
| kfree(notifier); |
| } |
| |
| /* If we bailed out because of an error in put_cmsg, |
| * we may be left with one or more notifications that we |
| * didn't process. Return them to the head of the list. */ |
| if (!list_empty(©)) { |
| spin_lock_irqsave(&rs->rs_lock, flags); |
| list_splice(©, &rs->rs_notify_queue); |
| spin_unlock_irqrestore(&rs->rs_lock, flags); |
| } |
| |
| return err; |
| } |
| |
| /* |
| * Queue a congestion notification |
| */ |
| static int rds_notify_cong(struct rds_sock *rs, struct msghdr *msghdr) |
| { |
| uint64_t notify = rs->rs_cong_notify; |
| unsigned long flags; |
| int err; |
| |
| err = put_cmsg(msghdr, SOL_RDS, RDS_CMSG_CONG_UPDATE, |
| sizeof(notify), ¬ify); |
| if (err) |
| return err; |
| |
| spin_lock_irqsave(&rs->rs_lock, flags); |
| rs->rs_cong_notify &= ~notify; |
| spin_unlock_irqrestore(&rs->rs_lock, flags); |
| |
| return 0; |
| } |
| |
| /* |
| * Receive any control messages. |
| */ |
| static int rds_cmsg_recv(struct rds_incoming *inc, struct msghdr *msg) |
| { |
| int ret = 0; |
| |
| if (inc->i_rdma_cookie) { |
| ret = put_cmsg(msg, SOL_RDS, RDS_CMSG_RDMA_DEST, |
| sizeof(inc->i_rdma_cookie), &inc->i_rdma_cookie); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| int rds_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, |
| size_t size, int msg_flags) |
| { |
| struct sock *sk = sock->sk; |
| struct rds_sock *rs = rds_sk_to_rs(sk); |
| long timeo; |
| int ret = 0, nonblock = msg_flags & MSG_DONTWAIT; |
| struct sockaddr_in *sin; |
| struct rds_incoming *inc = NULL; |
| |
| /* udp_recvmsg()->sock_recvtimeo() gets away without locking too.. */ |
| timeo = sock_rcvtimeo(sk, nonblock); |
| |
| rdsdebug("size %zu flags 0x%x timeo %ld\n", size, msg_flags, timeo); |
| |
| if (msg_flags & MSG_OOB) |
| goto out; |
| |
| while (1) { |
| /* If there are pending notifications, do those - and nothing else */ |
| if (!list_empty(&rs->rs_notify_queue)) { |
| ret = rds_notify_queue_get(rs, msg); |
| break; |
| } |
| |
| if (rs->rs_cong_notify) { |
| ret = rds_notify_cong(rs, msg); |
| break; |
| } |
| |
| if (!rds_next_incoming(rs, &inc)) { |
| if (nonblock) { |
| ret = -EAGAIN; |
| break; |
| } |
| |
| timeo = wait_event_interruptible_timeout(*sk->sk_sleep, |
| (!list_empty(&rs->rs_notify_queue) |
| || rs->rs_cong_notify |
| || rds_next_incoming(rs, &inc)), |
| timeo); |
| rdsdebug("recvmsg woke inc %p timeo %ld\n", inc, |
| timeo); |
| if (timeo > 0 || timeo == MAX_SCHEDULE_TIMEOUT) |
| continue; |
| |
| ret = timeo; |
| if (ret == 0) |
| ret = -ETIMEDOUT; |
| break; |
| } |
| |
| rdsdebug("copying inc %p from %pI4:%u to user\n", inc, |
| &inc->i_conn->c_faddr, |
| ntohs(inc->i_hdr.h_sport)); |
| ret = inc->i_conn->c_trans->inc_copy_to_user(inc, msg->msg_iov, |
| size); |
| if (ret < 0) |
| break; |
| |
| /* |
| * if the message we just copied isn't at the head of the |
| * recv queue then someone else raced us to return it, try |
| * to get the next message. |
| */ |
| if (!rds_still_queued(rs, inc, !(msg_flags & MSG_PEEK))) { |
| rds_inc_put(inc); |
| inc = NULL; |
| rds_stats_inc(s_recv_deliver_raced); |
| continue; |
| } |
| |
| if (ret < be32_to_cpu(inc->i_hdr.h_len)) { |
| if (msg_flags & MSG_TRUNC) |
| ret = be32_to_cpu(inc->i_hdr.h_len); |
| msg->msg_flags |= MSG_TRUNC; |
| } |
| |
| if (rds_cmsg_recv(inc, msg)) { |
| ret = -EFAULT; |
| goto out; |
| } |
| |
| rds_stats_inc(s_recv_delivered); |
| |
| sin = (struct sockaddr_in *)msg->msg_name; |
| if (sin) { |
| sin->sin_family = AF_INET; |
| sin->sin_port = inc->i_hdr.h_sport; |
| sin->sin_addr.s_addr = inc->i_saddr; |
| memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); |
| msg->msg_namelen = sizeof(*sin); |
| } |
| break; |
| } |
| |
| if (inc) |
| rds_inc_put(inc); |
| |
| out: |
| return ret; |
| } |
| |
| /* |
| * The socket is being shut down and we're asked to drop messages that were |
| * queued for recvmsg. The caller has unbound the socket so the receive path |
| * won't queue any more incoming fragments or messages on the socket. |
| */ |
| void rds_clear_recv_queue(struct rds_sock *rs) |
| { |
| struct sock *sk = rds_rs_to_sk(rs); |
| struct rds_incoming *inc, *tmp; |
| unsigned long flags; |
| |
| write_lock_irqsave(&rs->rs_recv_lock, flags); |
| list_for_each_entry_safe(inc, tmp, &rs->rs_recv_queue, i_item) { |
| rds_recv_rcvbuf_delta(rs, sk, inc->i_conn->c_lcong, |
| -be32_to_cpu(inc->i_hdr.h_len), |
| inc->i_hdr.h_dport); |
| list_del_init(&inc->i_item); |
| rds_inc_put(inc); |
| } |
| write_unlock_irqrestore(&rs->rs_recv_lock, flags); |
| } |
| |
| /* |
| * inc->i_saddr isn't used here because it is only set in the receive |
| * path. |
| */ |
| void rds_inc_info_copy(struct rds_incoming *inc, |
| struct rds_info_iterator *iter, |
| __be32 saddr, __be32 daddr, int flip) |
| { |
| struct rds_info_message minfo; |
| |
| minfo.seq = be64_to_cpu(inc->i_hdr.h_sequence); |
| minfo.len = be32_to_cpu(inc->i_hdr.h_len); |
| |
| if (flip) { |
| minfo.laddr = daddr; |
| minfo.faddr = saddr; |
| minfo.lport = inc->i_hdr.h_dport; |
| minfo.fport = inc->i_hdr.h_sport; |
| } else { |
| minfo.laddr = saddr; |
| minfo.faddr = daddr; |
| minfo.lport = inc->i_hdr.h_sport; |
| minfo.fport = inc->i_hdr.h_dport; |
| } |
| |
| rds_info_copy(iter, &minfo, sizeof(minfo)); |
| } |