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663 lines
19 KiB
663 lines
19 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Shared Memory Communications over RDMA (SMC-R) and RoCE |
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* |
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* Manage send buffer. |
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* Producer: |
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* Copy user space data into send buffer, if send buffer space available. |
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* Consumer: |
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* Trigger RDMA write into RMBE of peer and send CDC, if RMBE space available. |
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* |
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* Copyright IBM Corp. 2016 |
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* |
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* Author(s): Ursula Braun <[email protected]> |
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*/ |
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#include <linux/net.h> |
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#include <linux/rcupdate.h> |
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#include <linux/workqueue.h> |
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#include <linux/sched/signal.h> |
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#include <net/sock.h> |
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#include <net/tcp.h> |
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#include "smc.h" |
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#include "smc_wr.h" |
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#include "smc_cdc.h" |
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#include "smc_close.h" |
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#include "smc_ism.h" |
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#include "smc_tx.h" |
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#include "smc_stats.h" |
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#define SMC_TX_WORK_DELAY 0 |
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#define SMC_TX_CORK_DELAY (HZ >> 2) /* 250 ms */ |
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|
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/***************************** sndbuf producer *******************************/ |
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|
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/* callback implementation for sk.sk_write_space() |
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* to wakeup sndbuf producers that blocked with smc_tx_wait(). |
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* called under sk_socket lock. |
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*/ |
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static void smc_tx_write_space(struct sock *sk) |
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{ |
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struct socket *sock = sk->sk_socket; |
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struct smc_sock *smc = smc_sk(sk); |
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struct socket_wq *wq; |
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|
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/* similar to sk_stream_write_space */ |
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if (atomic_read(&smc->conn.sndbuf_space) && sock) { |
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if (test_bit(SOCK_NOSPACE, &sock->flags)) |
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SMC_STAT_RMB_TX_FULL(smc, !smc->conn.lnk); |
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clear_bit(SOCK_NOSPACE, &sock->flags); |
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rcu_read_lock(); |
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wq = rcu_dereference(sk->sk_wq); |
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if (skwq_has_sleeper(wq)) |
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wake_up_interruptible_poll(&wq->wait, |
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EPOLLOUT | EPOLLWRNORM | |
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EPOLLWRBAND); |
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if (wq && wq->fasync_list && !(sk->sk_shutdown & SEND_SHUTDOWN)) |
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sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT); |
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rcu_read_unlock(); |
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} |
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} |
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|
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/* Wakeup sndbuf producers that blocked with smc_tx_wait(). |
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* Cf. tcp_data_snd_check()=>tcp_check_space()=>tcp_new_space(). |
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*/ |
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void smc_tx_sndbuf_nonfull(struct smc_sock *smc) |
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{ |
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if (smc->sk.sk_socket && |
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test_bit(SOCK_NOSPACE, &smc->sk.sk_socket->flags)) |
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smc->sk.sk_write_space(&smc->sk); |
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} |
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|
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/* blocks sndbuf producer until at least one byte of free space available |
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* or urgent Byte was consumed |
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*/ |
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static int smc_tx_wait(struct smc_sock *smc, int flags) |
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{ |
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DEFINE_WAIT_FUNC(wait, woken_wake_function); |
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struct smc_connection *conn = &smc->conn; |
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struct sock *sk = &smc->sk; |
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long timeo; |
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int rc = 0; |
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|
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/* similar to sk_stream_wait_memory */ |
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timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); |
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add_wait_queue(sk_sleep(sk), &wait); |
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while (1) { |
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sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); |
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if (sk->sk_err || |
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(sk->sk_shutdown & SEND_SHUTDOWN) || |
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conn->killed || |
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conn->local_tx_ctrl.conn_state_flags.peer_done_writing) { |
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rc = -EPIPE; |
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break; |
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} |
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if (smc_cdc_rxed_any_close(conn)) { |
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rc = -ECONNRESET; |
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break; |
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} |
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if (!timeo) { |
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/* ensure EPOLLOUT is subsequently generated */ |
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set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); |
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rc = -EAGAIN; |
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break; |
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} |
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if (signal_pending(current)) { |
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rc = sock_intr_errno(timeo); |
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break; |
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} |
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sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); |
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if (atomic_read(&conn->sndbuf_space) && !conn->urg_tx_pend) |
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break; /* at least 1 byte of free & no urgent data */ |
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set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); |
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sk_wait_event(sk, &timeo, |
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sk->sk_err || |
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(sk->sk_shutdown & SEND_SHUTDOWN) || |
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smc_cdc_rxed_any_close(conn) || |
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(atomic_read(&conn->sndbuf_space) && |
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!conn->urg_tx_pend), |
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&wait); |
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} |
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remove_wait_queue(sk_sleep(sk), &wait); |
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return rc; |
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} |
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static bool smc_tx_is_corked(struct smc_sock *smc) |
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{ |
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struct tcp_sock *tp = tcp_sk(smc->clcsock->sk); |
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return (tp->nonagle & TCP_NAGLE_CORK) ? true : false; |
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} |
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/* sndbuf producer: main API called by socket layer. |
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* called under sock lock. |
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*/ |
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int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len) |
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{ |
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size_t copylen, send_done = 0, send_remaining = len; |
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size_t chunk_len, chunk_off, chunk_len_sum; |
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struct smc_connection *conn = &smc->conn; |
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union smc_host_cursor prep; |
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struct sock *sk = &smc->sk; |
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char *sndbuf_base; |
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int tx_cnt_prep; |
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int writespace; |
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int rc, chunk; |
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/* This should be in poll */ |
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sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); |
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if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) { |
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rc = -EPIPE; |
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goto out_err; |
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} |
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if (sk->sk_state == SMC_INIT) |
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return -ENOTCONN; |
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if (len > conn->sndbuf_desc->len) |
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SMC_STAT_RMB_TX_SIZE_SMALL(smc, !conn->lnk); |
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if (len > conn->peer_rmbe_size) |
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SMC_STAT_RMB_TX_PEER_SIZE_SMALL(smc, !conn->lnk); |
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if (msg->msg_flags & MSG_OOB) |
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SMC_STAT_INC(smc, urg_data_cnt); |
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while (msg_data_left(msg)) { |
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if (smc->sk.sk_shutdown & SEND_SHUTDOWN || |
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(smc->sk.sk_err == ECONNABORTED) || |
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conn->killed) |
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return -EPIPE; |
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if (smc_cdc_rxed_any_close(conn)) |
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return send_done ?: -ECONNRESET; |
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if (msg->msg_flags & MSG_OOB) |
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conn->local_tx_ctrl.prod_flags.urg_data_pending = 1; |
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if (!atomic_read(&conn->sndbuf_space) || conn->urg_tx_pend) { |
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if (send_done) |
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return send_done; |
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rc = smc_tx_wait(smc, msg->msg_flags); |
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if (rc) |
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goto out_err; |
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continue; |
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} |
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/* initialize variables for 1st iteration of subsequent loop */ |
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/* could be just 1 byte, even after smc_tx_wait above */ |
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writespace = atomic_read(&conn->sndbuf_space); |
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/* not more than what user space asked for */ |
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copylen = min_t(size_t, send_remaining, writespace); |
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/* determine start of sndbuf */ |
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sndbuf_base = conn->sndbuf_desc->cpu_addr; |
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smc_curs_copy(&prep, &conn->tx_curs_prep, conn); |
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tx_cnt_prep = prep.count; |
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/* determine chunks where to write into sndbuf */ |
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/* either unwrapped case, or 1st chunk of wrapped case */ |
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chunk_len = min_t(size_t, copylen, conn->sndbuf_desc->len - |
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tx_cnt_prep); |
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chunk_len_sum = chunk_len; |
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chunk_off = tx_cnt_prep; |
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smc_sndbuf_sync_sg_for_cpu(conn); |
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for (chunk = 0; chunk < 2; chunk++) { |
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rc = memcpy_from_msg(sndbuf_base + chunk_off, |
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msg, chunk_len); |
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if (rc) { |
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smc_sndbuf_sync_sg_for_device(conn); |
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if (send_done) |
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return send_done; |
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goto out_err; |
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} |
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send_done += chunk_len; |
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send_remaining -= chunk_len; |
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if (chunk_len_sum == copylen) |
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break; /* either on 1st or 2nd iteration */ |
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/* prepare next (== 2nd) iteration */ |
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chunk_len = copylen - chunk_len; /* remainder */ |
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chunk_len_sum += chunk_len; |
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chunk_off = 0; /* modulo offset in send ring buffer */ |
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} |
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smc_sndbuf_sync_sg_for_device(conn); |
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/* update cursors */ |
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smc_curs_add(conn->sndbuf_desc->len, &prep, copylen); |
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smc_curs_copy(&conn->tx_curs_prep, &prep, conn); |
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/* increased in send tasklet smc_cdc_tx_handler() */ |
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smp_mb__before_atomic(); |
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atomic_sub(copylen, &conn->sndbuf_space); |
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/* guarantee 0 <= sndbuf_space <= sndbuf_desc->len */ |
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smp_mb__after_atomic(); |
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/* since we just produced more new data into sndbuf, |
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* trigger sndbuf consumer: RDMA write into peer RMBE and CDC |
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*/ |
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if ((msg->msg_flags & MSG_OOB) && !send_remaining) |
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conn->urg_tx_pend = true; |
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if ((msg->msg_flags & MSG_MORE || smc_tx_is_corked(smc)) && |
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(atomic_read(&conn->sndbuf_space) > |
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(conn->sndbuf_desc->len >> 1))) |
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/* for a corked socket defer the RDMA writes if there |
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* is still sufficient sndbuf_space available |
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*/ |
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queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, |
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SMC_TX_CORK_DELAY); |
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else |
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smc_tx_sndbuf_nonempty(conn); |
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} /* while (msg_data_left(msg)) */ |
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return send_done; |
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out_err: |
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rc = sk_stream_error(sk, msg->msg_flags, rc); |
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/* make sure we wake any epoll edge trigger waiter */ |
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if (unlikely(rc == -EAGAIN)) |
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sk->sk_write_space(sk); |
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return rc; |
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} |
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/***************************** sndbuf consumer *******************************/ |
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/* sndbuf consumer: actual data transfer of one target chunk with ISM write */ |
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int smcd_tx_ism_write(struct smc_connection *conn, void *data, size_t len, |
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u32 offset, int signal) |
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{ |
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struct smc_ism_position pos; |
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int rc; |
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memset(&pos, 0, sizeof(pos)); |
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pos.token = conn->peer_token; |
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pos.index = conn->peer_rmbe_idx; |
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pos.offset = conn->tx_off + offset; |
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pos.signal = signal; |
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rc = smc_ism_write(conn->lgr->smcd, &pos, data, len); |
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if (rc) |
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conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1; |
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return rc; |
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} |
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/* sndbuf consumer: actual data transfer of one target chunk with RDMA write */ |
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static int smc_tx_rdma_write(struct smc_connection *conn, int peer_rmbe_offset, |
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int num_sges, struct ib_rdma_wr *rdma_wr) |
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{ |
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struct smc_link_group *lgr = conn->lgr; |
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struct smc_link *link = conn->lnk; |
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int rc; |
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rdma_wr->wr.wr_id = smc_wr_tx_get_next_wr_id(link); |
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rdma_wr->wr.num_sge = num_sges; |
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rdma_wr->remote_addr = |
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lgr->rtokens[conn->rtoken_idx][link->link_idx].dma_addr + |
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/* RMBE within RMB */ |
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conn->tx_off + |
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/* offset within RMBE */ |
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peer_rmbe_offset; |
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rdma_wr->rkey = lgr->rtokens[conn->rtoken_idx][link->link_idx].rkey; |
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rc = ib_post_send(link->roce_qp, &rdma_wr->wr, NULL); |
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if (rc) |
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smcr_link_down_cond_sched(link); |
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return rc; |
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} |
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/* sndbuf consumer */ |
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static inline void smc_tx_advance_cursors(struct smc_connection *conn, |
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union smc_host_cursor *prod, |
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union smc_host_cursor *sent, |
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size_t len) |
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{ |
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smc_curs_add(conn->peer_rmbe_size, prod, len); |
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/* increased in recv tasklet smc_cdc_msg_rcv() */ |
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smp_mb__before_atomic(); |
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/* data in flight reduces usable snd_wnd */ |
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atomic_sub(len, &conn->peer_rmbe_space); |
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/* guarantee 0 <= peer_rmbe_space <= peer_rmbe_size */ |
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smp_mb__after_atomic(); |
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smc_curs_add(conn->sndbuf_desc->len, sent, len); |
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} |
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/* SMC-R helper for smc_tx_rdma_writes() */ |
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static int smcr_tx_rdma_writes(struct smc_connection *conn, size_t len, |
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size_t src_off, size_t src_len, |
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size_t dst_off, size_t dst_len, |
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struct smc_rdma_wr *wr_rdma_buf) |
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{ |
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struct smc_link *link = conn->lnk; |
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dma_addr_t dma_addr = |
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sg_dma_address(conn->sndbuf_desc->sgt[link->link_idx].sgl); |
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int src_len_sum = src_len, dst_len_sum = dst_len; |
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int sent_count = src_off; |
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int srcchunk, dstchunk; |
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int num_sges; |
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int rc; |
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for (dstchunk = 0; dstchunk < 2; dstchunk++) { |
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struct ib_sge *sge = |
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wr_rdma_buf->wr_tx_rdma[dstchunk].wr.sg_list; |
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num_sges = 0; |
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for (srcchunk = 0; srcchunk < 2; srcchunk++) { |
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sge[srcchunk].addr = dma_addr + src_off; |
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sge[srcchunk].length = src_len; |
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num_sges++; |
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src_off += src_len; |
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if (src_off >= conn->sndbuf_desc->len) |
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src_off -= conn->sndbuf_desc->len; |
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/* modulo in send ring */ |
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if (src_len_sum == dst_len) |
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break; /* either on 1st or 2nd iteration */ |
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/* prepare next (== 2nd) iteration */ |
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src_len = dst_len - src_len; /* remainder */ |
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src_len_sum += src_len; |
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} |
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rc = smc_tx_rdma_write(conn, dst_off, num_sges, |
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&wr_rdma_buf->wr_tx_rdma[dstchunk]); |
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if (rc) |
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return rc; |
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if (dst_len_sum == len) |
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break; /* either on 1st or 2nd iteration */ |
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/* prepare next (== 2nd) iteration */ |
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dst_off = 0; /* modulo offset in RMBE ring buffer */ |
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dst_len = len - dst_len; /* remainder */ |
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dst_len_sum += dst_len; |
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src_len = min_t(int, dst_len, conn->sndbuf_desc->len - |
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sent_count); |
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src_len_sum = src_len; |
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} |
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return 0; |
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} |
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/* SMC-D helper for smc_tx_rdma_writes() */ |
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static int smcd_tx_rdma_writes(struct smc_connection *conn, size_t len, |
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size_t src_off, size_t src_len, |
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size_t dst_off, size_t dst_len) |
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{ |
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int src_len_sum = src_len, dst_len_sum = dst_len; |
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int srcchunk, dstchunk; |
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int rc; |
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for (dstchunk = 0; dstchunk < 2; dstchunk++) { |
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for (srcchunk = 0; srcchunk < 2; srcchunk++) { |
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void *data = conn->sndbuf_desc->cpu_addr + src_off; |
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rc = smcd_tx_ism_write(conn, data, src_len, dst_off + |
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sizeof(struct smcd_cdc_msg), 0); |
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if (rc) |
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return rc; |
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dst_off += src_len; |
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src_off += src_len; |
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if (src_off >= conn->sndbuf_desc->len) |
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src_off -= conn->sndbuf_desc->len; |
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/* modulo in send ring */ |
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if (src_len_sum == dst_len) |
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break; /* either on 1st or 2nd iteration */ |
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/* prepare next (== 2nd) iteration */ |
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src_len = dst_len - src_len; /* remainder */ |
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src_len_sum += src_len; |
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} |
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if (dst_len_sum == len) |
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break; /* either on 1st or 2nd iteration */ |
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/* prepare next (== 2nd) iteration */ |
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dst_off = 0; /* modulo offset in RMBE ring buffer */ |
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dst_len = len - dst_len; /* remainder */ |
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dst_len_sum += dst_len; |
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src_len = min_t(int, dst_len, conn->sndbuf_desc->len - src_off); |
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src_len_sum = src_len; |
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} |
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return 0; |
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} |
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|
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/* sndbuf consumer: prepare all necessary (src&dst) chunks of data transmit; |
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* usable snd_wnd as max transmit |
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*/ |
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static int smc_tx_rdma_writes(struct smc_connection *conn, |
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struct smc_rdma_wr *wr_rdma_buf) |
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{ |
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size_t len, src_len, dst_off, dst_len; /* current chunk values */ |
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union smc_host_cursor sent, prep, prod, cons; |
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struct smc_cdc_producer_flags *pflags; |
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int to_send, rmbespace; |
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int rc; |
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|
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/* source: sndbuf */ |
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smc_curs_copy(&sent, &conn->tx_curs_sent, conn); |
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smc_curs_copy(&prep, &conn->tx_curs_prep, conn); |
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/* cf. wmem_alloc - (snd_max - snd_una) */ |
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to_send = smc_curs_diff(conn->sndbuf_desc->len, &sent, &prep); |
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if (to_send <= 0) |
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return 0; |
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|
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/* destination: RMBE */ |
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/* cf. snd_wnd */ |
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rmbespace = atomic_read(&conn->peer_rmbe_space); |
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if (rmbespace <= 0) { |
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struct smc_sock *smc = container_of(conn, struct smc_sock, |
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conn); |
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SMC_STAT_RMB_TX_PEER_FULL(smc, !conn->lnk); |
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return 0; |
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} |
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smc_curs_copy(&prod, &conn->local_tx_ctrl.prod, conn); |
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smc_curs_copy(&cons, &conn->local_rx_ctrl.cons, conn); |
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|
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/* if usable snd_wnd closes ask peer to advertise once it opens again */ |
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pflags = &conn->local_tx_ctrl.prod_flags; |
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pflags->write_blocked = (to_send >= rmbespace); |
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/* cf. usable snd_wnd */ |
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len = min(to_send, rmbespace); |
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|
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/* initialize variables for first iteration of subsequent nested loop */ |
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dst_off = prod.count; |
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if (prod.wrap == cons.wrap) { |
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/* the filled destination area is unwrapped, |
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* hence the available free destination space is wrapped |
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* and we need 2 destination chunks of sum len; start with 1st |
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* which is limited by what's available in sndbuf |
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*/ |
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dst_len = min_t(size_t, |
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conn->peer_rmbe_size - prod.count, len); |
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} else { |
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/* the filled destination area is wrapped, |
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* hence the available free destination space is unwrapped |
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* and we need a single destination chunk of entire len |
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*/ |
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dst_len = len; |
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} |
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/* dst_len determines the maximum src_len */ |
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if (sent.count + dst_len <= conn->sndbuf_desc->len) { |
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/* unwrapped src case: single chunk of entire dst_len */ |
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src_len = dst_len; |
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} else { |
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/* wrapped src case: 2 chunks of sum dst_len; start with 1st: */ |
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src_len = conn->sndbuf_desc->len - sent.count; |
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} |
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|
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if (conn->lgr->is_smcd) |
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rc = smcd_tx_rdma_writes(conn, len, sent.count, src_len, |
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dst_off, dst_len); |
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else |
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rc = smcr_tx_rdma_writes(conn, len, sent.count, src_len, |
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dst_off, dst_len, wr_rdma_buf); |
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if (rc) |
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return rc; |
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|
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if (conn->urg_tx_pend && len == to_send) |
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pflags->urg_data_present = 1; |
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smc_tx_advance_cursors(conn, &prod, &sent, len); |
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/* update connection's cursors with advanced local cursors */ |
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smc_curs_copy(&conn->local_tx_ctrl.prod, &prod, conn); |
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/* dst: peer RMBE */ |
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smc_curs_copy(&conn->tx_curs_sent, &sent, conn);/* src: local sndbuf */ |
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|
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return 0; |
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} |
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|
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/* Wakeup sndbuf consumers from any context (IRQ or process) |
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* since there is more data to transmit; usable snd_wnd as max transmit |
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*/ |
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static int smcr_tx_sndbuf_nonempty(struct smc_connection *conn) |
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{ |
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struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags; |
|
struct smc_link *link = conn->lnk; |
|
struct smc_rdma_wr *wr_rdma_buf; |
|
struct smc_cdc_tx_pend *pend; |
|
struct smc_wr_buf *wr_buf; |
|
int rc; |
|
|
|
if (!link || !smc_wr_tx_link_hold(link)) |
|
return -ENOLINK; |
|
rc = smc_cdc_get_free_slot(conn, link, &wr_buf, &wr_rdma_buf, &pend); |
|
if (rc < 0) { |
|
smc_wr_tx_link_put(link); |
|
if (rc == -EBUSY) { |
|
struct smc_sock *smc = |
|
container_of(conn, struct smc_sock, conn); |
|
|
|
if (smc->sk.sk_err == ECONNABORTED) |
|
return sock_error(&smc->sk); |
|
if (conn->killed) |
|
return -EPIPE; |
|
rc = 0; |
|
mod_delayed_work(conn->lgr->tx_wq, &conn->tx_work, |
|
SMC_TX_WORK_DELAY); |
|
} |
|
return rc; |
|
} |
|
|
|
spin_lock_bh(&conn->send_lock); |
|
if (link != conn->lnk) { |
|
/* link of connection changed, tx_work will restart */ |
|
smc_wr_tx_put_slot(link, |
|
(struct smc_wr_tx_pend_priv *)pend); |
|
rc = -ENOLINK; |
|
goto out_unlock; |
|
} |
|
if (!pflags->urg_data_present) { |
|
rc = smc_tx_rdma_writes(conn, wr_rdma_buf); |
|
if (rc) { |
|
smc_wr_tx_put_slot(link, |
|
(struct smc_wr_tx_pend_priv *)pend); |
|
goto out_unlock; |
|
} |
|
} |
|
|
|
rc = smc_cdc_msg_send(conn, wr_buf, pend); |
|
if (!rc && pflags->urg_data_present) { |
|
pflags->urg_data_pending = 0; |
|
pflags->urg_data_present = 0; |
|
} |
|
|
|
out_unlock: |
|
spin_unlock_bh(&conn->send_lock); |
|
smc_wr_tx_link_put(link); |
|
return rc; |
|
} |
|
|
|
static int smcd_tx_sndbuf_nonempty(struct smc_connection *conn) |
|
{ |
|
struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags; |
|
int rc = 0; |
|
|
|
spin_lock_bh(&conn->send_lock); |
|
if (!pflags->urg_data_present) |
|
rc = smc_tx_rdma_writes(conn, NULL); |
|
if (!rc) |
|
rc = smcd_cdc_msg_send(conn); |
|
|
|
if (!rc && pflags->urg_data_present) { |
|
pflags->urg_data_pending = 0; |
|
pflags->urg_data_present = 0; |
|
} |
|
spin_unlock_bh(&conn->send_lock); |
|
return rc; |
|
} |
|
|
|
int smc_tx_sndbuf_nonempty(struct smc_connection *conn) |
|
{ |
|
int rc; |
|
|
|
if (conn->killed || |
|
conn->local_rx_ctrl.conn_state_flags.peer_conn_abort) |
|
return -EPIPE; /* connection being aborted */ |
|
if (conn->lgr->is_smcd) |
|
rc = smcd_tx_sndbuf_nonempty(conn); |
|
else |
|
rc = smcr_tx_sndbuf_nonempty(conn); |
|
|
|
if (!rc) { |
|
/* trigger socket release if connection is closing */ |
|
struct smc_sock *smc = container_of(conn, struct smc_sock, |
|
conn); |
|
smc_close_wake_tx_prepared(smc); |
|
} |
|
return rc; |
|
} |
|
|
|
/* Wakeup sndbuf consumers from process context |
|
* since there is more data to transmit |
|
*/ |
|
void smc_tx_work(struct work_struct *work) |
|
{ |
|
struct smc_connection *conn = container_of(to_delayed_work(work), |
|
struct smc_connection, |
|
tx_work); |
|
struct smc_sock *smc = container_of(conn, struct smc_sock, conn); |
|
int rc; |
|
|
|
lock_sock(&smc->sk); |
|
if (smc->sk.sk_err) |
|
goto out; |
|
|
|
rc = smc_tx_sndbuf_nonempty(conn); |
|
if (!rc && conn->local_rx_ctrl.prod_flags.write_blocked && |
|
!atomic_read(&conn->bytes_to_rcv)) |
|
conn->local_rx_ctrl.prod_flags.write_blocked = 0; |
|
|
|
out: |
|
release_sock(&smc->sk); |
|
} |
|
|
|
void smc_tx_consumer_update(struct smc_connection *conn, bool force) |
|
{ |
|
union smc_host_cursor cfed, cons, prod; |
|
int sender_free = conn->rmb_desc->len; |
|
int to_confirm; |
|
|
|
smc_curs_copy(&cons, &conn->local_tx_ctrl.cons, conn); |
|
smc_curs_copy(&cfed, &conn->rx_curs_confirmed, conn); |
|
to_confirm = smc_curs_diff(conn->rmb_desc->len, &cfed, &cons); |
|
if (to_confirm > conn->rmbe_update_limit) { |
|
smc_curs_copy(&prod, &conn->local_rx_ctrl.prod, conn); |
|
sender_free = conn->rmb_desc->len - |
|
smc_curs_diff_large(conn->rmb_desc->len, |
|
&cfed, &prod); |
|
} |
|
|
|
if (conn->local_rx_ctrl.prod_flags.cons_curs_upd_req || |
|
force || |
|
((to_confirm > conn->rmbe_update_limit) && |
|
((sender_free <= (conn->rmb_desc->len / 2)) || |
|
conn->local_rx_ctrl.prod_flags.write_blocked))) { |
|
if (conn->killed || |
|
conn->local_rx_ctrl.conn_state_flags.peer_conn_abort) |
|
return; |
|
if ((smc_cdc_get_slot_and_msg_send(conn) < 0) && |
|
!conn->killed) { |
|
queue_delayed_work(conn->lgr->tx_wq, &conn->tx_work, |
|
SMC_TX_WORK_DELAY); |
|
return; |
|
} |
|
} |
|
if (conn->local_rx_ctrl.prod_flags.write_blocked && |
|
!atomic_read(&conn->bytes_to_rcv)) |
|
conn->local_rx_ctrl.prod_flags.write_blocked = 0; |
|
} |
|
|
|
/***************************** send initialize *******************************/ |
|
|
|
/* Initialize send properties on connection establishment. NB: not __init! */ |
|
void smc_tx_init(struct smc_sock *smc) |
|
{ |
|
smc->sk.sk_write_space = smc_tx_write_space; |
|
}
|
|
|