| /* |
| * 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 <linux/moduleparam.h> |
| #include <linux/gfp.h> |
| #include <net/sock.h> |
| #include <linux/in.h> |
| #include <linux/list.h> |
| #include <linux/ratelimit.h> |
| #include <linux/export.h> |
| #include <linux/sizes.h> |
| |
| #include "rds.h" |
| |
| /* When transmitting messages in rds_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 = SZ_1K; |
| module_param(send_batch_count, int, 0444); |
| MODULE_PARM_DESC(send_batch_count, " batch factor when working the send queue"); |
| |
| static void rds_send_remove_from_sock(struct list_head *messages, int status); |
| |
| /* |
| * Reset the send state. Callers must ensure that this doesn't race with |
| * rds_send_xmit(). |
| */ |
| void rds_send_path_reset(struct rds_conn_path *cp) |
| { |
| struct rds_message *rm, *tmp; |
| unsigned long flags; |
| |
| if (cp->cp_xmit_rm) { |
| rm = cp->cp_xmit_rm; |
| cp->cp_xmit_rm = NULL; |
| /* 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 */ |
| rds_message_unmapped(rm); |
| rds_message_put(rm); |
| } |
| |
| cp->cp_xmit_sg = 0; |
| cp->cp_xmit_hdr_off = 0; |
| cp->cp_xmit_data_off = 0; |
| cp->cp_xmit_atomic_sent = 0; |
| cp->cp_xmit_rdma_sent = 0; |
| cp->cp_xmit_data_sent = 0; |
| |
| cp->cp_conn->c_map_queued = 0; |
| |
| cp->cp_unacked_packets = rds_sysctl_max_unacked_packets; |
| cp->cp_unacked_bytes = rds_sysctl_max_unacked_bytes; |
| |
| /* Mark messages as retransmissions, and move them to the send q */ |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| list_for_each_entry_safe(rm, tmp, &cp->cp_retrans, m_conn_item) { |
| set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); |
| set_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags); |
| } |
| list_splice_init(&cp->cp_retrans, &cp->cp_send_queue); |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| } |
| EXPORT_SYMBOL_GPL(rds_send_path_reset); |
| |
| static int acquire_in_xmit(struct rds_conn_path *cp) |
| { |
| return test_and_set_bit(RDS_IN_XMIT, &cp->cp_flags) == 0; |
| } |
| |
| static void release_in_xmit(struct rds_conn_path *cp) |
| { |
| clear_bit(RDS_IN_XMIT, &cp->cp_flags); |
| smp_mb__after_atomic(); |
| /* |
| * We don't use wait_on_bit()/wake_up_bit() because our waking is in a |
| * hot path and finding waiters is very rare. We don't want to walk |
| * the system-wide hashed waitqueue buckets in the fast path only to |
| * almost never find waiters. |
| */ |
| if (waitqueue_active(&cp->cp_waitq)) |
| wake_up_all(&cp->cp_waitq); |
| } |
| |
| /* |
| * We're making the conscious 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 rds_send_xmit(struct rds_conn_path *cp) |
| { |
| struct rds_connection *conn = cp->cp_conn; |
| struct rds_message *rm; |
| unsigned long flags; |
| unsigned int tmp; |
| struct scatterlist *sg; |
| int ret = 0; |
| LIST_HEAD(to_be_dropped); |
| int batch_count; |
| unsigned long send_gen = 0; |
| |
| restart: |
| batch_count = 0; |
| |
| /* |
| * 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. |
| */ |
| if (!acquire_in_xmit(cp)) { |
| rds_stats_inc(s_send_lock_contention); |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (rds_destroy_pending(cp->cp_conn)) { |
| release_in_xmit(cp); |
| ret = -ENETUNREACH; /* dont requeue send work */ |
| goto out; |
| } |
| |
| /* |
| * we record the send generation after doing the xmit acquire. |
| * if someone else manages to jump in and do some work, we'll use |
| * this to avoid a goto restart farther down. |
| * |
| * The acquire_in_xmit() check above ensures that only one |
| * caller can increment c_send_gen at any time. |
| */ |
| send_gen = READ_ONCE(cp->cp_send_gen) + 1; |
| WRITE_ONCE(cp->cp_send_gen, send_gen); |
| |
| /* |
| * rds_conn_shutdown() sets the conn state and then tests RDS_IN_XMIT, |
| * we do the opposite to avoid races. |
| */ |
| if (!rds_conn_path_up(cp)) { |
| release_in_xmit(cp); |
| ret = 0; |
| goto out; |
| } |
| |
| if (conn->c_trans->xmit_path_prepare) |
| conn->c_trans->xmit_path_prepare(cp); |
| |
| /* |
| * spin trying to push headers and data down the connection until |
| * the connection doesn't make forward progress. |
| */ |
| while (1) { |
| |
| rm = cp->cp_xmit_rm; |
| |
| /* |
| * If between sending messages, we can send a pending congestion |
| * map update. |
| */ |
| if (!rm && test_and_clear_bit(0, &conn->c_map_queued)) { |
| rm = rds_cong_update_alloc(conn); |
| if (IS_ERR(rm)) { |
| ret = PTR_ERR(rm); |
| break; |
| } |
| rm->data.op_active = 1; |
| rm->m_inc.i_conn_path = cp; |
| rm->m_inc.i_conn = cp->cp_conn; |
| |
| cp->cp_xmit_rm = rm; |
| } |
| |
| /* |
| * If not already working on one, grab the next message. |
| * |
| * cp_xmit_rm holds a ref while we're sending this message down |
| * the connction. We can use this ref while holding the |
| * send_sem.. rds_send_reset() is serialized with it. |
| */ |
| if (!rm) { |
| unsigned int len; |
| |
| batch_count++; |
| |
| /* we want to process as big a batch as we can, but |
| * we also want to avoid softlockups. If we've been |
| * through a lot of messages, lets back off and see |
| * if anyone else jumps in |
| */ |
| if (batch_count >= send_batch_count) |
| goto over_batch; |
| |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| |
| if (!list_empty(&cp->cp_send_queue)) { |
| rm = list_entry(cp->cp_send_queue.next, |
| struct rds_message, |
| m_conn_item); |
| rds_message_addref(rm); |
| |
| /* |
| * Move the message from the send queue to the retransmit |
| * list right away. |
| */ |
| list_move_tail(&rm->m_conn_item, |
| &cp->cp_retrans); |
| } |
| |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| |
| if (!rm) |
| 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 (test_bit(RDS_MSG_FLUSH, &rm->m_flags) || |
| (rm->rdma.op_active && |
| test_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags))) { |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| if (test_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags)) |
| list_move(&rm->m_conn_item, &to_be_dropped); |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| continue; |
| } |
| |
| /* Require an ACK every once in a while */ |
| len = ntohl(rm->m_inc.i_hdr.h_len); |
| if (cp->cp_unacked_packets == 0 || |
| cp->cp_unacked_bytes < len) { |
| set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); |
| |
| cp->cp_unacked_packets = |
| rds_sysctl_max_unacked_packets; |
| cp->cp_unacked_bytes = |
| rds_sysctl_max_unacked_bytes; |
| rds_stats_inc(s_send_ack_required); |
| } else { |
| cp->cp_unacked_bytes -= len; |
| cp->cp_unacked_packets--; |
| } |
| |
| cp->cp_xmit_rm = rm; |
| } |
| |
| /* The transport either sends the whole rdma or none of it */ |
| if (rm->rdma.op_active && !cp->cp_xmit_rdma_sent) { |
| rm->m_final_op = &rm->rdma; |
| /* The transport owns the mapped memory for now. |
| * You can't unmap it while it's on the send queue |
| */ |
| set_bit(RDS_MSG_MAPPED, &rm->m_flags); |
| ret = conn->c_trans->xmit_rdma(conn, &rm->rdma); |
| if (ret) { |
| clear_bit(RDS_MSG_MAPPED, &rm->m_flags); |
| wake_up_interruptible(&rm->m_flush_wait); |
| break; |
| } |
| cp->cp_xmit_rdma_sent = 1; |
| |
| } |
| |
| if (rm->atomic.op_active && !cp->cp_xmit_atomic_sent) { |
| rm->m_final_op = &rm->atomic; |
| /* The transport owns the mapped memory for now. |
| * You can't unmap it while it's on the send queue |
| */ |
| set_bit(RDS_MSG_MAPPED, &rm->m_flags); |
| ret = conn->c_trans->xmit_atomic(conn, &rm->atomic); |
| if (ret) { |
| clear_bit(RDS_MSG_MAPPED, &rm->m_flags); |
| wake_up_interruptible(&rm->m_flush_wait); |
| break; |
| } |
| cp->cp_xmit_atomic_sent = 1; |
| |
| } |
| |
| /* |
| * A number of cases require an RDS header to be sent |
| * even if there is no data. |
| * We permit 0-byte sends; rds-ping depends on this. |
| * However, if there are exclusively attached silent ops, |
| * we skip the hdr/data send, to enable silent operation. |
| */ |
| if (rm->data.op_nents == 0) { |
| int ops_present; |
| int all_ops_are_silent = 1; |
| |
| ops_present = (rm->atomic.op_active || rm->rdma.op_active); |
| if (rm->atomic.op_active && !rm->atomic.op_silent) |
| all_ops_are_silent = 0; |
| if (rm->rdma.op_active && !rm->rdma.op_silent) |
| all_ops_are_silent = 0; |
| |
| if (ops_present && all_ops_are_silent |
| && !rm->m_rdma_cookie) |
| rm->data.op_active = 0; |
| } |
| |
| if (rm->data.op_active && !cp->cp_xmit_data_sent) { |
| rm->m_final_op = &rm->data; |
| |
| ret = conn->c_trans->xmit(conn, rm, |
| cp->cp_xmit_hdr_off, |
| cp->cp_xmit_sg, |
| cp->cp_xmit_data_off); |
| if (ret <= 0) |
| break; |
| |
| if (cp->cp_xmit_hdr_off < sizeof(struct rds_header)) { |
| tmp = min_t(int, ret, |
| sizeof(struct rds_header) - |
| cp->cp_xmit_hdr_off); |
| cp->cp_xmit_hdr_off += tmp; |
| ret -= tmp; |
| } |
| |
| sg = &rm->data.op_sg[cp->cp_xmit_sg]; |
| while (ret) { |
| tmp = min_t(int, ret, sg->length - |
| cp->cp_xmit_data_off); |
| cp->cp_xmit_data_off += tmp; |
| ret -= tmp; |
| if (cp->cp_xmit_data_off == sg->length) { |
| cp->cp_xmit_data_off = 0; |
| sg++; |
| cp->cp_xmit_sg++; |
| BUG_ON(ret != 0 && cp->cp_xmit_sg == |
| rm->data.op_nents); |
| } |
| } |
| |
| if (cp->cp_xmit_hdr_off == sizeof(struct rds_header) && |
| (cp->cp_xmit_sg == rm->data.op_nents)) |
| cp->cp_xmit_data_sent = 1; |
| } |
| |
| /* |
| * A rm will only take multiple times through this loop |
| * if there is a data op. Thus, if the data is sent (or there was |
| * none), then we're done with the rm. |
| */ |
| if (!rm->data.op_active || cp->cp_xmit_data_sent) { |
| cp->cp_xmit_rm = NULL; |
| cp->cp_xmit_sg = 0; |
| cp->cp_xmit_hdr_off = 0; |
| cp->cp_xmit_data_off = 0; |
| cp->cp_xmit_rdma_sent = 0; |
| cp->cp_xmit_atomic_sent = 0; |
| cp->cp_xmit_data_sent = 0; |
| |
| rds_message_put(rm); |
| } |
| } |
| |
| over_batch: |
| if (conn->c_trans->xmit_path_complete) |
| conn->c_trans->xmit_path_complete(cp); |
| release_in_xmit(cp); |
| |
| /* Nuke any messages we decided not to retransmit. */ |
| if (!list_empty(&to_be_dropped)) { |
| /* irqs on here, so we can put(), unlike above */ |
| list_for_each_entry(rm, &to_be_dropped, m_conn_item) |
| rds_message_put(rm); |
| rds_send_remove_from_sock(&to_be_dropped, RDS_RDMA_DROPPED); |
| } |
| |
| /* |
| * Other senders can queue a message after we last test the send queue |
| * but before we clear RDS_IN_XMIT. In that case they'd back off and |
| * not try and send their newly queued message. We need to check the |
| * send queue after having cleared RDS_IN_XMIT so that their message |
| * doesn't get stuck on the send queue. |
| * |
| * If the transport cannot continue (i.e ret != 0), then it must |
| * call us when more room is available, such as from the tx |
| * completion handler. |
| * |
| * We have an extra generation check here so that if someone manages |
| * to jump in after our release_in_xmit, we'll see that they have done |
| * some work and we will skip our goto |
| */ |
| if (ret == 0) { |
| bool raced; |
| |
| smp_mb(); |
| raced = send_gen != READ_ONCE(cp->cp_send_gen); |
| |
| if ((test_bit(0, &conn->c_map_queued) || |
| !list_empty(&cp->cp_send_queue)) && !raced) { |
| if (batch_count < send_batch_count) |
| goto restart; |
| rcu_read_lock(); |
| if (rds_destroy_pending(cp->cp_conn)) |
| ret = -ENETUNREACH; |
| else |
| queue_delayed_work(rds_wq, &cp->cp_send_w, 1); |
| rcu_read_unlock(); |
| } else if (raced) { |
| rds_stats_inc(s_send_lock_queue_raced); |
| } |
| } |
| out: |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(rds_send_xmit); |
| |
| static void rds_send_sndbuf_remove(struct rds_sock *rs, struct rds_message *rm) |
| { |
| u32 len = be32_to_cpu(rm->m_inc.i_hdr.h_len); |
| |
| assert_spin_locked(&rs->rs_lock); |
| |
| BUG_ON(rs->rs_snd_bytes < len); |
| rs->rs_snd_bytes -= len; |
| |
| if (rs->rs_snd_bytes == 0) |
| rds_stats_inc(s_send_queue_empty); |
| } |
| |
| static inline int rds_send_is_acked(struct rds_message *rm, u64 ack, |
| is_acked_func is_acked) |
| { |
| if (is_acked) |
| return is_acked(rm, ack); |
| return be64_to_cpu(rm->m_inc.i_hdr.h_sequence) <= ack; |
| } |
| |
| /* |
| * 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 rds_rdma_send_complete(struct rds_message *rm, int status) |
| { |
| struct rds_sock *rs = NULL; |
| struct rm_rdma_op *ro; |
| struct rds_notifier *notifier; |
| unsigned long flags; |
| unsigned int notify = 0; |
| |
| spin_lock_irqsave(&rm->m_rs_lock, flags); |
| |
| notify = rm->rdma.op_notify | rm->data.op_notify; |
| ro = &rm->rdma; |
| if (test_bit(RDS_MSG_ON_SOCK, &rm->m_flags) && |
| ro->op_active && notify && ro->op_notifier) { |
| notifier = ro->op_notifier; |
| rs = rm->m_rs; |
| sock_hold(rds_rs_to_sk(rs)); |
| |
| notifier->n_status = status; |
| spin_lock(&rs->rs_lock); |
| list_add_tail(¬ifier->n_list, &rs->rs_notify_queue); |
| spin_unlock(&rs->rs_lock); |
| |
| ro->op_notifier = NULL; |
| } |
| |
| spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
| |
| if (rs) { |
| rds_wake_sk_sleep(rs); |
| sock_put(rds_rs_to_sk(rs)); |
| } |
| } |
| EXPORT_SYMBOL_GPL(rds_rdma_send_complete); |
| |
| /* |
| * Just like above, except looks at atomic op |
| */ |
| void rds_atomic_send_complete(struct rds_message *rm, int status) |
| { |
| struct rds_sock *rs = NULL; |
| struct rm_atomic_op *ao; |
| struct rds_notifier *notifier; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&rm->m_rs_lock, flags); |
| |
| ao = &rm->atomic; |
| if (test_bit(RDS_MSG_ON_SOCK, &rm->m_flags) |
| && ao->op_active && ao->op_notify && ao->op_notifier) { |
| notifier = ao->op_notifier; |
| rs = rm->m_rs; |
| sock_hold(rds_rs_to_sk(rs)); |
| |
| notifier->n_status = status; |
| spin_lock(&rs->rs_lock); |
| list_add_tail(¬ifier->n_list, &rs->rs_notify_queue); |
| spin_unlock(&rs->rs_lock); |
| |
| ao->op_notifier = NULL; |
| } |
| |
| spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
| |
| if (rs) { |
| rds_wake_sk_sleep(rs); |
| sock_put(rds_rs_to_sk(rs)); |
| } |
| } |
| EXPORT_SYMBOL_GPL(rds_atomic_send_complete); |
| |
| /* |
| * This is the same as rds_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 |
| __rds_send_complete(struct rds_sock *rs, struct rds_message *rm, int status) |
| { |
| struct rm_rdma_op *ro; |
| struct rm_atomic_op *ao; |
| |
| ro = &rm->rdma; |
| if (ro->op_active && ro->op_notify && ro->op_notifier) { |
| ro->op_notifier->n_status = status; |
| list_add_tail(&ro->op_notifier->n_list, &rs->rs_notify_queue); |
| ro->op_notifier = NULL; |
| } |
| |
| ao = &rm->atomic; |
| if (ao->op_active && ao->op_notify && ao->op_notifier) { |
| ao->op_notifier->n_status = status; |
| list_add_tail(&ao->op_notifier->n_list, &rs->rs_notify_queue); |
| ao->op_notifier = NULL; |
| } |
| |
| /* No need to wake the app - caller does this */ |
| } |
| |
| /* |
| * 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. |
| */ |
| static void rds_send_remove_from_sock(struct list_head *messages, int status) |
| { |
| unsigned long flags; |
| struct rds_sock *rs = NULL; |
| struct rds_message *rm; |
| |
| while (!list_empty(messages)) { |
| int was_on_sock = 0; |
| |
| rm = list_entry(messages->next, struct rds_message, |
| m_conn_item); |
| list_del_init(&rm->m_conn_item); |
| |
| /* |
| * 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. |
| */ |
| spin_lock_irqsave(&rm->m_rs_lock, flags); |
| if (!test_bit(RDS_MSG_ON_SOCK, &rm->m_flags)) |
| goto unlock_and_drop; |
| |
| if (rs != rm->m_rs) { |
| if (rs) { |
| rds_wake_sk_sleep(rs); |
| sock_put(rds_rs_to_sk(rs)); |
| } |
| rs = rm->m_rs; |
| if (rs) |
| sock_hold(rds_rs_to_sk(rs)); |
| } |
| if (!rs) |
| goto unlock_and_drop; |
| spin_lock(&rs->rs_lock); |
| |
| if (test_and_clear_bit(RDS_MSG_ON_SOCK, &rm->m_flags)) { |
| struct rm_rdma_op *ro = &rm->rdma; |
| struct rds_notifier *notifier; |
| |
| list_del_init(&rm->m_sock_item); |
| rds_send_sndbuf_remove(rs, rm); |
| |
| if (ro->op_active && ro->op_notifier && |
| (ro->op_notify || (ro->op_recverr && status))) { |
| notifier = ro->op_notifier; |
| list_add_tail(¬ifier->n_list, |
| &rs->rs_notify_queue); |
| if (!notifier->n_status) |
| notifier->n_status = status; |
| rm->rdma.op_notifier = NULL; |
| } |
| was_on_sock = 1; |
| } |
| spin_unlock(&rs->rs_lock); |
| |
| unlock_and_drop: |
| spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
| rds_message_put(rm); |
| if (was_on_sock) |
| rds_message_put(rm); |
| } |
| |
| if (rs) { |
| rds_wake_sk_sleep(rs); |
| sock_put(rds_rs_to_sk(rs)); |
| } |
| } |
| |
| /* |
| * 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 rds_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 RDS_MSG_HAS_ACK_SEQ bit. |
| */ |
| void rds_send_path_drop_acked(struct rds_conn_path *cp, u64 ack, |
| is_acked_func is_acked) |
| { |
| struct rds_message *rm, *tmp; |
| unsigned long flags; |
| LIST_HEAD(list); |
| |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| |
| list_for_each_entry_safe(rm, tmp, &cp->cp_retrans, m_conn_item) { |
| if (!rds_send_is_acked(rm, ack, is_acked)) |
| break; |
| |
| list_move(&rm->m_conn_item, &list); |
| clear_bit(RDS_MSG_ON_CONN, &rm->m_flags); |
| } |
| |
| /* order flag updates with spin locks */ |
| if (!list_empty(&list)) |
| smp_mb__after_atomic(); |
| |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| |
| /* now remove the messages from the sock list as needed */ |
| rds_send_remove_from_sock(&list, RDS_RDMA_SUCCESS); |
| } |
| EXPORT_SYMBOL_GPL(rds_send_path_drop_acked); |
| |
| void rds_send_drop_acked(struct rds_connection *conn, u64 ack, |
| is_acked_func is_acked) |
| { |
| WARN_ON(conn->c_trans->t_mp_capable); |
| rds_send_path_drop_acked(&conn->c_path[0], ack, is_acked); |
| } |
| EXPORT_SYMBOL_GPL(rds_send_drop_acked); |
| |
| void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest) |
| { |
| struct rds_message *rm, *tmp; |
| struct rds_connection *conn; |
| struct rds_conn_path *cp; |
| unsigned long flags; |
| LIST_HEAD(list); |
| |
| /* get all the messages we're dropping under the rs lock */ |
| spin_lock_irqsave(&rs->rs_lock, flags); |
| |
| list_for_each_entry_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; |
| |
| list_move(&rm->m_sock_item, &list); |
| rds_send_sndbuf_remove(rs, rm); |
| clear_bit(RDS_MSG_ON_SOCK, &rm->m_flags); |
| } |
| |
| /* order flag updates with the rs lock */ |
| smp_mb__after_atomic(); |
| |
| spin_unlock_irqrestore(&rs->rs_lock, flags); |
| |
| if (list_empty(&list)) |
| return; |
| |
| /* Remove the messages from the conn */ |
| list_for_each_entry(rm, &list, m_sock_item) { |
| |
| conn = rm->m_inc.i_conn; |
| if (conn->c_trans->t_mp_capable) |
| cp = rm->m_inc.i_conn_path; |
| else |
| cp = &conn->c_path[0]; |
| |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| /* |
| * Maybe someone else beat us to removing rm 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_and_clear_bit(RDS_MSG_ON_CONN, &rm->m_flags)) { |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| continue; |
| } |
| list_del_init(&rm->m_conn_item); |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| |
| /* |
| * Couldn't grab m_rs_lock in top loop (lock ordering), |
| * but we can now. |
| */ |
| spin_lock_irqsave(&rm->m_rs_lock, flags); |
| |
| spin_lock(&rs->rs_lock); |
| __rds_send_complete(rs, rm, RDS_RDMA_CANCELED); |
| spin_unlock(&rs->rs_lock); |
| |
| spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
| |
| rds_message_put(rm); |
| } |
| |
| rds_wake_sk_sleep(rs); |
| |
| while (!list_empty(&list)) { |
| rm = list_entry(list.next, struct rds_message, m_sock_item); |
| list_del_init(&rm->m_sock_item); |
| rds_message_wait(rm); |
| |
| /* just in case the code above skipped this message |
| * because RDS_MSG_ON_CONN wasn't set, run it again here |
| * taking m_rs_lock is the only thing that keeps us |
| * from racing with ack processing. |
| */ |
| spin_lock_irqsave(&rm->m_rs_lock, flags); |
| |
| spin_lock(&rs->rs_lock); |
| __rds_send_complete(rs, rm, RDS_RDMA_CANCELED); |
| spin_unlock(&rs->rs_lock); |
| |
| spin_unlock_irqrestore(&rm->m_rs_lock, flags); |
| |
| rds_message_put(rm); |
| } |
| } |
| |
| /* |
| * 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 RDS_CANCEL_SENT_TO. |
| */ |
| static int rds_send_queue_rm(struct rds_sock *rs, struct rds_connection *conn, |
| struct rds_conn_path *cp, |
| struct rds_message *rm, __be16 sport, |
| __be16 dport, int *queued) |
| { |
| unsigned long flags; |
| u32 len; |
| |
| if (*queued) |
| goto out; |
| |
| len = be32_to_cpu(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 */ |
| spin_lock_irqsave(&rs->rs_lock, flags); |
| |
| /* |
| * 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 < rds_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 >= rds_sk_sndbuf(rs) / 2) |
| set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); |
| |
| list_add_tail(&rm->m_sock_item, &rs->rs_send_queue); |
| set_bit(RDS_MSG_ON_SOCK, &rm->m_flags); |
| rds_message_addref(rm); |
| sock_hold(rds_rs_to_sk(rs)); |
| rm->m_rs = rs; |
| |
| /* The code ordering is a little weird, but we're |
| trying to minimize the time we hold c_lock */ |
| rds_message_populate_header(&rm->m_inc.i_hdr, sport, dport, 0); |
| rm->m_inc.i_conn = conn; |
| rm->m_inc.i_conn_path = cp; |
| rds_message_addref(rm); |
| |
| spin_lock(&cp->cp_lock); |
| rm->m_inc.i_hdr.h_sequence = cpu_to_be64(cp->cp_next_tx_seq++); |
| list_add_tail(&rm->m_conn_item, &cp->cp_send_queue); |
| set_bit(RDS_MSG_ON_CONN, &rm->m_flags); |
| spin_unlock(&cp->cp_lock); |
| |
| rdsdebug("queued msg %p len %d, rs %p bytes %d seq %llu\n", |
| rm, len, rs, rs->rs_snd_bytes, |
| (unsigned long long)be64_to_cpu(rm->m_inc.i_hdr.h_sequence)); |
| |
| *queued = 1; |
| } |
| |
| spin_unlock_irqrestore(&rs->rs_lock, flags); |
| out: |
| return *queued; |
| } |
| |
| /* |
| * rds_message is getting to be quite complicated, and we'd like to allocate |
| * it all in one go. This figures out how big it needs to be up front. |
| */ |
| static int rds_rm_size(struct msghdr *msg, int num_sgs) |
| { |
| struct cmsghdr *cmsg; |
| int size = 0; |
| int cmsg_groups = 0; |
| int retval; |
| bool zcopy_cookie = false; |
| |
| for_each_cmsghdr(cmsg, msg) { |
| if (!CMSG_OK(msg, cmsg)) |
| return -EINVAL; |
| |
| if (cmsg->cmsg_level != SOL_RDS) |
| continue; |
| |
| switch (cmsg->cmsg_type) { |
| case RDS_CMSG_RDMA_ARGS: |
| cmsg_groups |= 1; |
| retval = rds_rdma_extra_size(CMSG_DATA(cmsg)); |
| if (retval < 0) |
| return retval; |
| size += retval; |
| |
| break; |
| |
| case RDS_CMSG_ZCOPY_COOKIE: |
| zcopy_cookie = true; |
| case RDS_CMSG_RDMA_DEST: |
| case RDS_CMSG_RDMA_MAP: |
| cmsg_groups |= 2; |
| /* these are valid but do no add any size */ |
| break; |
| |
| case RDS_CMSG_ATOMIC_CSWP: |
| case RDS_CMSG_ATOMIC_FADD: |
| case RDS_CMSG_MASKED_ATOMIC_CSWP: |
| case RDS_CMSG_MASKED_ATOMIC_FADD: |
| cmsg_groups |= 1; |
| size += sizeof(struct scatterlist); |
| break; |
| |
| default: |
| return -EINVAL; |
| } |
| |
| } |
| |
| if ((msg->msg_flags & MSG_ZEROCOPY) && !zcopy_cookie) |
| return -EINVAL; |
| |
| size += num_sgs * sizeof(struct scatterlist); |
| |
| /* Ensure (DEST, MAP) are never used with (ARGS, ATOMIC) */ |
| if (cmsg_groups == 3) |
| return -EINVAL; |
| |
| return size; |
| } |
| |
| static int rds_cmsg_zcopy(struct rds_sock *rs, struct rds_message *rm, |
| struct cmsghdr *cmsg) |
| { |
| u32 *cookie; |
| |
| if (cmsg->cmsg_len < CMSG_LEN(sizeof(*cookie))) |
| return -EINVAL; |
| cookie = CMSG_DATA(cmsg); |
| rm->data.op_mmp_znotifier->z_cookie = *cookie; |
| return 0; |
| } |
| |
| static int rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm, |
| struct msghdr *msg, int *allocated_mr) |
| { |
| struct cmsghdr *cmsg; |
| int ret = 0; |
| |
| for_each_cmsghdr(cmsg, msg) { |
| if (!CMSG_OK(msg, cmsg)) |
| return -EINVAL; |
| |
| if (cmsg->cmsg_level != SOL_RDS) |
| continue; |
| |
| /* As a side effect, RDMA_DEST and RDMA_MAP will set |
| * rm->rdma.m_rdma_cookie and rm->rdma.m_rdma_mr. |
| */ |
| switch (cmsg->cmsg_type) { |
| case RDS_CMSG_RDMA_ARGS: |
| ret = rds_cmsg_rdma_args(rs, rm, cmsg); |
| break; |
| |
| case RDS_CMSG_RDMA_DEST: |
| ret = rds_cmsg_rdma_dest(rs, rm, cmsg); |
| break; |
| |
| case RDS_CMSG_RDMA_MAP: |
| ret = rds_cmsg_rdma_map(rs, rm, cmsg); |
| if (!ret) |
| *allocated_mr = 1; |
| else if (ret == -ENODEV) |
| /* Accommodate the get_mr() case which can fail |
| * if connection isn't established yet. |
| */ |
| ret = -EAGAIN; |
| break; |
| case RDS_CMSG_ATOMIC_CSWP: |
| case RDS_CMSG_ATOMIC_FADD: |
| case RDS_CMSG_MASKED_ATOMIC_CSWP: |
| case RDS_CMSG_MASKED_ATOMIC_FADD: |
| ret = rds_cmsg_atomic(rs, rm, cmsg); |
| break; |
| |
| case RDS_CMSG_ZCOPY_COOKIE: |
| ret = rds_cmsg_zcopy(rs, rm, cmsg); |
| break; |
| |
| default: |
| return -EINVAL; |
| } |
| |
| if (ret) |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static int rds_send_mprds_hash(struct rds_sock *rs, struct rds_connection *conn) |
| { |
| int hash; |
| |
| if (conn->c_npaths == 0) |
| hash = RDS_MPATH_HASH(rs, RDS_MPATH_WORKERS); |
| else |
| hash = RDS_MPATH_HASH(rs, conn->c_npaths); |
| if (conn->c_npaths == 0 && hash != 0) { |
| rds_send_ping(conn, 0); |
| |
| if (conn->c_npaths == 0) { |
| wait_event_interruptible(conn->c_hs_waitq, |
| (conn->c_npaths != 0)); |
| } |
| if (conn->c_npaths == 1) |
| hash = 0; |
| } |
| return hash; |
| } |
| |
| static int rds_rdma_bytes(struct msghdr *msg, size_t *rdma_bytes) |
| { |
| struct rds_rdma_args *args; |
| struct cmsghdr *cmsg; |
| |
| for_each_cmsghdr(cmsg, msg) { |
| if (!CMSG_OK(msg, cmsg)) |
| return -EINVAL; |
| |
| if (cmsg->cmsg_level != SOL_RDS) |
| continue; |
| |
| if (cmsg->cmsg_type == RDS_CMSG_RDMA_ARGS) { |
| if (cmsg->cmsg_len < |
| CMSG_LEN(sizeof(struct rds_rdma_args))) |
| return -EINVAL; |
| args = CMSG_DATA(cmsg); |
| *rdma_bytes += args->remote_vec.bytes; |
| } |
| } |
| return 0; |
| } |
| |
| int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len) |
| { |
| struct sock *sk = sock->sk; |
| struct rds_sock *rs = rds_sk_to_rs(sk); |
| DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name); |
| __be32 daddr; |
| __be16 dport; |
| struct rds_message *rm = NULL; |
| struct rds_connection *conn; |
| int ret = 0; |
| int queued = 0, allocated_mr = 0; |
| int nonblock = msg->msg_flags & MSG_DONTWAIT; |
| long timeo = sock_sndtimeo(sk, nonblock); |
| struct rds_conn_path *cpath; |
| size_t total_payload_len = payload_len, rdma_payload_len = 0; |
| bool zcopy = ((msg->msg_flags & MSG_ZEROCOPY) && |
| sock_flag(rds_rs_to_sk(rs), SOCK_ZEROCOPY)); |
| int num_sgs = ceil(payload_len, PAGE_SIZE); |
| |
| /* Mirror Linux UDP mirror of BSD error message compatibility */ |
| /* XXX: Perhaps MSG_MORE someday */ |
| if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_CMSG_COMPAT | MSG_ZEROCOPY)) { |
| ret = -EOPNOTSUPP; |
| goto out; |
| } |
| |
| if (msg->msg_namelen) { |
| /* XXX fail non-unicast destination IPs? */ |
| if (msg->msg_namelen < sizeof(*usin) || usin->sin_family != AF_INET) { |
| ret = -EINVAL; |
| goto out; |
| } |
| daddr = usin->sin_addr.s_addr; |
| dport = usin->sin_port; |
| } else { |
| /* We only care about consistency with ->connect() */ |
| lock_sock(sk); |
| daddr = rs->rs_conn_addr; |
| dport = rs->rs_conn_port; |
| release_sock(sk); |
| } |
| |
| lock_sock(sk); |
| if (daddr == 0 || rs->rs_bound_addr == 0) { |
| release_sock(sk); |
| ret = -ENOTCONN; /* XXX not a great errno */ |
| goto out; |
| } |
| release_sock(sk); |
| |
| ret = rds_rdma_bytes(msg, &rdma_payload_len); |
| if (ret) |
| goto out; |
| |
| total_payload_len += rdma_payload_len; |
| if (max_t(size_t, payload_len, rdma_payload_len) > RDS_MAX_MSG_SIZE) { |
| ret = -EMSGSIZE; |
| goto out; |
| } |
| |
| if (payload_len > rds_sk_sndbuf(rs)) { |
| ret = -EMSGSIZE; |
| goto out; |
| } |
| |
| if (zcopy) { |
| if (rs->rs_transport->t_type != RDS_TRANS_TCP) { |
| ret = -EOPNOTSUPP; |
| goto out; |
| } |
| num_sgs = iov_iter_npages(&msg->msg_iter, INT_MAX); |
| } |
| /* size of rm including all sgs */ |
| ret = rds_rm_size(msg, num_sgs); |
| if (ret < 0) |
| goto out; |
| |
| rm = rds_message_alloc(ret, GFP_KERNEL); |
| if (!rm) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| /* Attach data to the rm */ |
| if (payload_len) { |
| rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs); |
| if (!rm->data.op_sg) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| ret = rds_message_copy_from_user(rm, &msg->msg_iter, zcopy); |
| if (ret) |
| goto out; |
| } |
| rm->data.op_active = 1; |
| |
| rm->m_daddr = daddr; |
| |
| /* rds_conn_create has a spinlock that runs with IRQ off. |
| * Caching the conn in the socket helps a lot. */ |
| if (rs->rs_conn && rs->rs_conn->c_faddr == daddr) |
| conn = rs->rs_conn; |
| else { |
| conn = rds_conn_create_outgoing(sock_net(sock->sk), |
| rs->rs_bound_addr, daddr, |
| rs->rs_transport, |
| sock->sk->sk_allocation); |
| if (IS_ERR(conn)) { |
| ret = PTR_ERR(conn); |
| goto out; |
| } |
| rs->rs_conn = conn; |
| } |
| |
| /* Parse any control messages the user may have included. */ |
| ret = rds_cmsg_send(rs, rm, msg, &allocated_mr); |
| if (ret) { |
| /* Trigger connection so that its ready for the next retry */ |
| if (ret == -EAGAIN) |
| rds_conn_connect_if_down(conn); |
| goto out; |
| } |
| |
| if (rm->rdma.op_active && !conn->c_trans->xmit_rdma) { |
| printk_ratelimited(KERN_NOTICE "rdma_op %p conn xmit_rdma %p\n", |
| &rm->rdma, conn->c_trans->xmit_rdma); |
| ret = -EOPNOTSUPP; |
| goto out; |
| } |
| |
| if (rm->atomic.op_active && !conn->c_trans->xmit_atomic) { |
| printk_ratelimited(KERN_NOTICE "atomic_op %p conn xmit_atomic %p\n", |
| &rm->atomic, conn->c_trans->xmit_atomic); |
| ret = -EOPNOTSUPP; |
| goto out; |
| } |
| |
| if (conn->c_trans->t_mp_capable) |
| cpath = &conn->c_path[rds_send_mprds_hash(rs, conn)]; |
| else |
| cpath = &conn->c_path[0]; |
| |
| if (rds_destroy_pending(conn)) { |
| ret = -EAGAIN; |
| goto out; |
| } |
| |
| rds_conn_path_connect_if_down(cpath); |
| |
| ret = rds_cong_wait(conn->c_fcong, dport, nonblock, rs); |
| if (ret) { |
| rs->rs_seen_congestion = 1; |
| goto out; |
| } |
| while (!rds_send_queue_rm(rs, conn, cpath, rm, rs->rs_bound_port, |
| dport, &queued)) { |
| rds_stats_inc(s_send_queue_full); |
| |
| if (nonblock) { |
| ret = -EAGAIN; |
| goto out; |
| } |
| |
| timeo = wait_event_interruptible_timeout(*sk_sleep(sk), |
| rds_send_queue_rm(rs, conn, cpath, rm, |
| rs->rs_bound_port, |
| dport, |
| &queued), |
| timeo); |
| rdsdebug("sendmsg woke queued %d timeo %ld\n", queued, timeo); |
| if (timeo > 0 || timeo == MAX_SCHEDULE_TIMEOUT) |
| continue; |
| |
| ret = timeo; |
| if (ret == 0) |
| ret = -ETIMEDOUT; |
| goto out; |
| } |
| |
| /* |
| * By now we've committed to the send. We reuse rds_send_worker() |
| * to retry sends in the rds thread if the transport asks us to. |
| */ |
| rds_stats_inc(s_send_queued); |
| |
| ret = rds_send_xmit(cpath); |
| if (ret == -ENOMEM || ret == -EAGAIN) { |
| ret = 0; |
| rcu_read_lock(); |
| if (rds_destroy_pending(cpath->cp_conn)) |
| ret = -ENETUNREACH; |
| else |
| queue_delayed_work(rds_wq, &cpath->cp_send_w, 1); |
| rcu_read_unlock(); |
| } |
| if (ret) |
| goto out; |
| rds_message_put(rm); |
| 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) |
| rds_rdma_unuse(rs, rds_rdma_cookie_key(rm->m_rdma_cookie), 1); |
| |
| if (rm) |
| rds_message_put(rm); |
| return ret; |
| } |
| |
| /* |
| * send out a probe. Can be shared by rds_send_ping, |
| * rds_send_pong, rds_send_hb. |
| * rds_send_hb should use h_flags |
| * RDS_FLAG_HB_PING|RDS_FLAG_ACK_REQUIRED |
| * or |
| * RDS_FLAG_HB_PONG|RDS_FLAG_ACK_REQUIRED |
| */ |
| static int |
| rds_send_probe(struct rds_conn_path *cp, __be16 sport, |
| __be16 dport, u8 h_flags) |
| { |
| struct rds_message *rm; |
| unsigned long flags; |
| int ret = 0; |
| |
| rm = rds_message_alloc(0, GFP_ATOMIC); |
| if (!rm) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| rm->m_daddr = cp->cp_conn->c_faddr; |
| rm->data.op_active = 1; |
| |
| rds_conn_path_connect_if_down(cp); |
| |
| ret = rds_cong_wait(cp->cp_conn->c_fcong, dport, 1, NULL); |
| if (ret) |
| goto out; |
| |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| list_add_tail(&rm->m_conn_item, &cp->cp_send_queue); |
| set_bit(RDS_MSG_ON_CONN, &rm->m_flags); |
| rds_message_addref(rm); |
| rm->m_inc.i_conn = cp->cp_conn; |
| rm->m_inc.i_conn_path = cp; |
| |
| rds_message_populate_header(&rm->m_inc.i_hdr, sport, dport, |
| cp->cp_next_tx_seq); |
| rm->m_inc.i_hdr.h_flags |= h_flags; |
| cp->cp_next_tx_seq++; |
| |
| if (RDS_HS_PROBE(be16_to_cpu(sport), be16_to_cpu(dport)) && |
| cp->cp_conn->c_trans->t_mp_capable) { |
| u16 npaths = cpu_to_be16(RDS_MPATH_WORKERS); |
| u32 my_gen_num = cpu_to_be32(cp->cp_conn->c_my_gen_num); |
| |
| rds_message_add_extension(&rm->m_inc.i_hdr, |
| RDS_EXTHDR_NPATHS, &npaths, |
| sizeof(npaths)); |
| rds_message_add_extension(&rm->m_inc.i_hdr, |
| RDS_EXTHDR_GEN_NUM, |
| &my_gen_num, |
| sizeof(u32)); |
| } |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| |
| rds_stats_inc(s_send_queued); |
| rds_stats_inc(s_send_pong); |
| |
| /* schedule the send work on rds_wq */ |
| rcu_read_lock(); |
| if (!rds_destroy_pending(cp->cp_conn)) |
| queue_delayed_work(rds_wq, &cp->cp_send_w, 1); |
| rcu_read_unlock(); |
| |
| rds_message_put(rm); |
| return 0; |
| |
| out: |
| if (rm) |
| rds_message_put(rm); |
| return ret; |
| } |
| |
| int |
| rds_send_pong(struct rds_conn_path *cp, __be16 dport) |
| { |
| return rds_send_probe(cp, 0, dport, 0); |
| } |
| |
| void |
| rds_send_ping(struct rds_connection *conn, int cp_index) |
| { |
| unsigned long flags; |
| struct rds_conn_path *cp = &conn->c_path[cp_index]; |
| |
| spin_lock_irqsave(&cp->cp_lock, flags); |
| if (conn->c_ping_triggered) { |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| return; |
| } |
| conn->c_ping_triggered = 1; |
| spin_unlock_irqrestore(&cp->cp_lock, flags); |
| rds_send_probe(cp, cpu_to_be16(RDS_FLAG_PROBE_PORT), 0, 0); |
| } |
| EXPORT_SYMBOL_GPL(rds_send_ping); |