From be244f28d22f77d939ba2b973c102ad2b49d3496 Mon Sep 17 00:00:00 2001 From: Hans Wippel Date: Thu, 28 Jun 2018 19:05:10 +0200 Subject: net/smc: add SMC-D support in data transfer The data transfer and CDC message headers differ in SMC-R and SMC-D. This patch adds support for the SMC-D data transfer to the existing SMC code. It consists of the following: * SMC-D CDC support * SMC-D tx support * SMC-D rx support The CDC header is stored at the beginning of the receive buffer. Thus, a rx_offset variable is added for the CDC header offset within the buffer (0 for SMC-R). Signed-off-by: Hans Wippel Signed-off-by: Ursula Braun Suggested-by: Thomas Richter Signed-off-by: David S. Miller --- net/smc/smc_cdc.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 84 insertions(+), 2 deletions(-) (limited to 'net/smc/smc_cdc.c') diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c index a7e8d63fc8ae..621d8cca570b 100644 --- a/net/smc/smc_cdc.c +++ b/net/smc/smc_cdc.c @@ -117,7 +117,7 @@ int smc_cdc_msg_send(struct smc_connection *conn, return rc; } -int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn) +static int smcr_cdc_get_slot_and_msg_send(struct smc_connection *conn) { struct smc_cdc_tx_pend *pend; struct smc_wr_buf *wr_buf; @@ -130,6 +130,21 @@ int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn) return smc_cdc_msg_send(conn, wr_buf, pend); } +int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn) +{ + int rc; + + if (conn->lgr->is_smcd) { + spin_lock_bh(&conn->send_lock); + rc = smcd_cdc_msg_send(conn); + spin_unlock_bh(&conn->send_lock); + } else { + rc = smcr_cdc_get_slot_and_msg_send(conn); + } + + return rc; +} + static bool smc_cdc_tx_filter(struct smc_wr_tx_pend_priv *tx_pend, unsigned long data) { @@ -157,6 +172,45 @@ void smc_cdc_tx_dismiss_slots(struct smc_connection *conn) (unsigned long)conn); } +/* Send a SMC-D CDC header. + * This increments the free space available in our send buffer. + * Also update the confirmed receive buffer with what was sent to the peer. + */ +int smcd_cdc_msg_send(struct smc_connection *conn) +{ + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + struct smcd_cdc_msg cdc; + int rc, diff; + + memset(&cdc, 0, sizeof(cdc)); + cdc.common.type = SMC_CDC_MSG_TYPE; + cdc.prod_wrap = conn->local_tx_ctrl.prod.wrap; + cdc.prod_count = conn->local_tx_ctrl.prod.count; + + cdc.cons_wrap = conn->local_tx_ctrl.cons.wrap; + cdc.cons_count = conn->local_tx_ctrl.cons.count; + cdc.prod_flags = conn->local_tx_ctrl.prod_flags; + cdc.conn_state_flags = conn->local_tx_ctrl.conn_state_flags; + rc = smcd_tx_ism_write(conn, &cdc, sizeof(cdc), 0, 1); + if (rc) + return rc; + smc_curs_write(&conn->rx_curs_confirmed, + smc_curs_read(&conn->local_tx_ctrl.cons, conn), conn); + /* Calculate transmitted data and increment free send buffer space */ + diff = smc_curs_diff(conn->sndbuf_desc->len, &conn->tx_curs_fin, + &conn->tx_curs_sent); + /* increased by confirmed number of bytes */ + smp_mb__before_atomic(); + atomic_add(diff, &conn->sndbuf_space); + /* guarantee 0 <= sndbuf_space <= sndbuf_desc->len */ + smp_mb__after_atomic(); + smc_curs_write(&conn->tx_curs_fin, + smc_curs_read(&conn->tx_curs_sent, conn), conn); + + smc_tx_sndbuf_nonfull(smc); + return rc; +} + /********************************* receive ***********************************/ static inline bool smc_cdc_before(u16 seq1, u16 seq2) @@ -178,7 +232,7 @@ static void smc_cdc_handle_urg_data_arrival(struct smc_sock *smc, if (!sock_flag(&smc->sk, SOCK_URGINLINE)) /* we'll skip the urgent byte, so don't account for it */ (*diff_prod)--; - base = (char *)conn->rmb_desc->cpu_addr; + base = (char *)conn->rmb_desc->cpu_addr + conn->rx_off; if (conn->urg_curs.count) conn->urg_rx_byte = *(base + conn->urg_curs.count - 1); else @@ -276,6 +330,34 @@ static void smc_cdc_msg_recv(struct smc_sock *smc, struct smc_cdc_msg *cdc) sock_put(&smc->sk); /* no free sk in softirq-context */ } +/* Schedule a tasklet for this connection. Triggered from the ISM device IRQ + * handler to indicate update in the DMBE. + * + * Context: + * - tasklet context + */ +static void smcd_cdc_rx_tsklet(unsigned long data) +{ + struct smc_connection *conn = (struct smc_connection *)data; + struct smcd_cdc_msg cdc; + struct smc_sock *smc; + + if (!conn) + return; + + memcpy(&cdc, conn->rmb_desc->cpu_addr, sizeof(cdc)); + smc = container_of(conn, struct smc_sock, conn); + smc_cdc_msg_recv(smc, (struct smc_cdc_msg *)&cdc); +} + +/* Initialize receive tasklet. Called from ISM device IRQ handler to start + * receiver side. + */ +void smcd_cdc_rx_init(struct smc_connection *conn) +{ + tasklet_init(&conn->rx_tsklet, smcd_cdc_rx_tsklet, (unsigned long)conn); +} + /***************************** init, exit, misc ******************************/ static void smc_cdc_rx_handler(struct ib_wc *wc, void *buf) -- cgit v1.2.3