Initial commit: OpenHarmony-v4.0-ReleaseOpenHarmony-v4.0-Release

1 files changed, 476 insertions, 0 deletions

diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c
new file mode 100644
index 000000000..94503f36b
--- /dev/null
+++ b/net/smc/smc_cdc.c
@@ -0,0 +1,476 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Shared Memory Communications over RDMA (SMC-R) and RoCE
+ *
+ * Connection Data Control (CDC)
+ * handles flow control
+ *
+ * Copyright IBM Corp. 2016
+ *
+ * Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
+ */
+
+#include <linux/spinlock.h>
+
+#include "smc.h"
+#include "smc_wr.h"
+#include "smc_cdc.h"
+#include "smc_tx.h"
+#include "smc_rx.h"
+#include "smc_close.h"
+
+/********************************** send *************************************/
+
+/* handler for send/transmission completion of a CDC msg */
+static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd,
+                               struct smc_link *link,
+                               enum ib_wc_status wc_status)
+{
+        struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend *)pnd_snd;
+        struct smc_connection *conn = cdcpend->conn;
+        struct smc_sock *smc;
+        int diff;
+
+        smc = container_of(conn, struct smc_sock, conn);
+        bh_lock_sock(&smc->sk);
+        if (!wc_status) {
+                diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len,
+                                     &cdcpend->conn->tx_curs_fin,
+                                     &cdcpend->cursor);
+                /* sndbuf_space is decreased in smc_sendmsg */
+                smp_mb__before_atomic();
+                atomic_add(diff, &cdcpend->conn->sndbuf_space);
+                /* guarantee 0 <= sndbuf_space <= sndbuf_desc->len */
+                smp_mb__after_atomic();
+                smc_curs_copy(&conn->tx_curs_fin, &cdcpend->cursor, conn);
+                smc_curs_copy(&conn->local_tx_ctrl_fin, &cdcpend->p_cursor,
+                              conn);
+                conn->tx_cdc_seq_fin = cdcpend->ctrl_seq;
+        }
+
+        if (atomic_dec_and_test(&conn->cdc_pend_tx_wr) &&
+            unlikely(wq_has_sleeper(&conn->cdc_pend_tx_wq)))
+                wake_up(&conn->cdc_pend_tx_wq);
+        WARN_ON(atomic_read(&conn->cdc_pend_tx_wr) < 0);
+
+        smc_tx_sndbuf_nonfull(smc);
+        bh_unlock_sock(&smc->sk);
+}
+
+int smc_cdc_get_free_slot(struct smc_connection *conn,
+                          struct smc_link *link,
+                          struct smc_wr_buf **wr_buf,
+                          struct smc_rdma_wr **wr_rdma_buf,
+                          struct smc_cdc_tx_pend **pend)
+{
+        int rc;
+
+        rc = smc_wr_tx_get_free_slot(link, smc_cdc_tx_handler, wr_buf,
+                                     wr_rdma_buf,
+                                     (struct smc_wr_tx_pend_priv **)pend);
+        if (conn->killed) {
+                /* abnormal termination */
+                if (!rc)
+                        smc_wr_tx_put_slot(link,
+                                           (struct smc_wr_tx_pend_priv *)(*pend));
+                rc = -EPIPE;
+        }
+        return rc;
+}
+
+static inline void smc_cdc_add_pending_send(struct smc_connection *conn,
+                                            struct smc_cdc_tx_pend *pend)
+{
+        BUILD_BUG_ON_MSG(
+                sizeof(struct smc_cdc_msg) > SMC_WR_BUF_SIZE,
+                "must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_cdc_msg)");
+        BUILD_BUG_ON_MSG(
+                offsetofend(struct smc_cdc_msg, reserved) > SMC_WR_TX_SIZE,
+                "must adapt SMC_WR_TX_SIZE to sizeof(struct smc_cdc_msg); if not all smc_wr upper layer protocols use the same message size any more, must start to set link->wr_tx_sges[i].length on each individual smc_wr_tx_send()");
+        BUILD_BUG_ON_MSG(
+                sizeof(struct smc_cdc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE,
+                "must increase SMC_WR_TX_PEND_PRIV_SIZE to at least sizeof(struct smc_cdc_tx_pend)");
+        pend->conn = conn;
+        pend->cursor = conn->tx_curs_sent;
+        pend->p_cursor = conn->local_tx_ctrl.prod;
+        pend->ctrl_seq = conn->tx_cdc_seq;
+}
+
+int smc_cdc_msg_send(struct smc_connection *conn,
+                     struct smc_wr_buf *wr_buf,
+                     struct smc_cdc_tx_pend *pend)
+{
+        struct smc_link *link = conn->lnk;
+        union smc_host_cursor cfed;
+        int rc;
+
+        smc_cdc_add_pending_send(conn, pend);
+
+        conn->tx_cdc_seq++;
+        conn->local_tx_ctrl.seqno = conn->tx_cdc_seq;
+        smc_host_msg_to_cdc((struct smc_cdc_msg *)wr_buf, conn, &cfed);
+
+        atomic_inc(&conn->cdc_pend_tx_wr);
+        smp_mb__after_atomic(); /* Make sure cdc_pend_tx_wr added before post */
+
+        rc = smc_wr_tx_send(link, (struct smc_wr_tx_pend_priv *)pend);
+        if (!rc) {
+                smc_curs_copy(&conn->rx_curs_confirmed, &cfed, conn);
+                conn->local_rx_ctrl.prod_flags.cons_curs_upd_req = 0;
+        } else {
+                conn->tx_cdc_seq--;
+                conn->local_tx_ctrl.seqno = conn->tx_cdc_seq;
+                atomic_dec(&conn->cdc_pend_tx_wr);
+        }
+
+        return rc;
+}
+
+/* send a validation msg indicating the move of a conn to an other QP link */
+int smcr_cdc_msg_send_validation(struct smc_connection *conn,
+                                 struct smc_cdc_tx_pend *pend,
+                                 struct smc_wr_buf *wr_buf)
+{
+        struct smc_host_cdc_msg *local = &conn->local_tx_ctrl;
+        struct smc_link *link = conn->lnk;
+        struct smc_cdc_msg *peer;
+        int rc;
+
+        peer = (struct smc_cdc_msg *)wr_buf;
+        peer->common.type = local->common.type;
+        peer->len = local->len;
+        peer->seqno = htons(conn->tx_cdc_seq_fin); /* seqno last compl. tx */
+        peer->token = htonl(local->token);
+        peer->prod_flags.failover_validation = 1;
+
+        /* We need to set pend->conn here to make sure smc_cdc_tx_handler()
+         * can handle properly
+         */
+        smc_cdc_add_pending_send(conn, pend);
+
+        atomic_inc(&conn->cdc_pend_tx_wr);
+        smp_mb__after_atomic(); /* Make sure cdc_pend_tx_wr added before post */
+
+        rc = smc_wr_tx_send(link, (struct smc_wr_tx_pend_priv *)pend);
+        if (unlikely(rc))
+                atomic_dec(&conn->cdc_pend_tx_wr);
+
+        return rc;
+}
+
+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;
+        struct smc_link *link;
+        bool again = false;
+        int rc;
+
+again:
+        link = conn->lnk;
+        if (!smc_wr_tx_link_hold(link))
+                return -ENOLINK;
+        rc = smc_cdc_get_free_slot(conn, link, &wr_buf, NULL, &pend);
+        if (rc)
+                goto put_out;
+
+        spin_lock_bh(&conn->send_lock);
+        if (link != conn->lnk) {
+                /* link of connection changed, try again one time*/
+                spin_unlock_bh(&conn->send_lock);
+                smc_wr_tx_put_slot(link,
+                                   (struct smc_wr_tx_pend_priv *)pend);
+                smc_wr_tx_link_put(link);
+                if (again)
+                        return -ENOLINK;
+                again = true;
+                goto again;
+        }
+        rc = smc_cdc_msg_send(conn, wr_buf, pend);
+        spin_unlock_bh(&conn->send_lock);
+put_out:
+        smc_wr_tx_link_put(link);
+        return rc;
+}
+
+int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
+{
+        int rc;
+
+        if (!conn->lgr || (conn->lgr->is_smcd && conn->lgr->peer_shutdown))
+                return -EPIPE;
+
+        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;
+}
+
+void smc_cdc_wait_pend_tx_wr(struct smc_connection *conn)
+{
+        wait_event(conn->cdc_pend_tx_wq, !atomic_read(&conn->cdc_pend_tx_wr));
+}
+
+/* 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);
+        union smc_host_cursor curs;
+        struct smcd_cdc_msg cdc;
+        int rc, diff;
+
+        memset(&cdc, 0, sizeof(cdc));
+        cdc.common.type = SMC_CDC_MSG_TYPE;
+        curs.acurs.counter = atomic64_read(&conn->local_tx_ctrl.prod.acurs);
+        cdc.prod.wrap = curs.wrap;
+        cdc.prod.count = curs.count;
+        curs.acurs.counter = atomic64_read(&conn->local_tx_ctrl.cons.acurs);
+        cdc.cons.wrap = curs.wrap;
+        cdc.cons.count = curs.count;
+        cdc.cons.prod_flags = conn->local_tx_ctrl.prod_flags;
+        cdc.cons.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_copy(&conn->rx_curs_confirmed, &curs, conn);
+        conn->local_rx_ctrl.prod_flags.cons_curs_upd_req = 0;
+        /* 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_copy(&conn->tx_curs_fin, &conn->tx_curs_sent, conn);
+
+        smc_tx_sndbuf_nonfull(smc);
+        return rc;
+}
+
+/********************************* receive ***********************************/
+
+static inline bool smc_cdc_before(u16 seq1, u16 seq2)
+{
+        return (s16)(seq1 - seq2) < 0;
+}
+
+static void smc_cdc_handle_urg_data_arrival(struct smc_sock *smc,
+                                            int *diff_prod)
+{
+        struct smc_connection *conn = &smc->conn;
+        char *base;
+
+        /* new data included urgent business */
+        smc_curs_copy(&conn->urg_curs, &conn->local_rx_ctrl.prod, conn);
+        conn->urg_state = SMC_URG_VALID;
+        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 + conn->rx_off;
+        if (conn->urg_curs.count)
+                conn->urg_rx_byte = *(base + conn->urg_curs.count - 1);
+        else
+                conn->urg_rx_byte = *(base + conn->rmb_desc->len - 1);
+        sk_send_sigurg(&smc->sk);
+}
+
+static void smc_cdc_msg_validate(struct smc_sock *smc, struct smc_cdc_msg *cdc,
+                                 struct smc_link *link)
+{
+        struct smc_connection *conn = &smc->conn;
+        u16 recv_seq = ntohs(cdc->seqno);
+        s16 diff;
+
+        /* check that seqnum was seen before */
+        diff = conn->local_rx_ctrl.seqno - recv_seq;
+        if (diff < 0) { /* diff larger than 0x7fff */
+                /* drop connection */
+                conn->out_of_sync = 1;  /* prevent any further receives */
+                spin_lock_bh(&conn->send_lock);
+                conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
+                conn->lnk = link;
+                spin_unlock_bh(&conn->send_lock);
+                sock_hold(&smc->sk); /* sock_put in abort_work */
+                if (!queue_work(smc_close_wq, &conn->abort_work))
+                        sock_put(&smc->sk);
+        }
+}
+
+static void smc_cdc_msg_recv_action(struct smc_sock *smc,
+                                    struct smc_cdc_msg *cdc)
+{
+        union smc_host_cursor cons_old, prod_old;
+        struct smc_connection *conn = &smc->conn;
+        int diff_cons, diff_prod;
+
+        smc_curs_copy(&prod_old, &conn->local_rx_ctrl.prod, conn);
+        smc_curs_copy(&cons_old, &conn->local_rx_ctrl.cons, conn);
+        smc_cdc_msg_to_host(&conn->local_rx_ctrl, cdc, conn);
+
+        diff_cons = smc_curs_diff(conn->peer_rmbe_size, &cons_old,
+                                  &conn->local_rx_ctrl.cons);
+        if (diff_cons) {
+                /* peer_rmbe_space is decreased during data transfer with RDMA
+                 * write
+                 */
+                smp_mb__before_atomic();
+                atomic_add(diff_cons, &conn->peer_rmbe_space);
+                /* guarantee 0 <= peer_rmbe_space <= peer_rmbe_size */
+                smp_mb__after_atomic();
+        }
+
+        diff_prod = smc_curs_diff(conn->rmb_desc->len, &prod_old,
+                                  &conn->local_rx_ctrl.prod);
+        if (diff_prod) {
+                if (conn->local_rx_ctrl.prod_flags.urg_data_present)
+                        smc_cdc_handle_urg_data_arrival(smc, &diff_prod);
+                /* bytes_to_rcv is decreased in smc_recvmsg */
+                smp_mb__before_atomic();
+                atomic_add(diff_prod, &conn->bytes_to_rcv);
+                /* guarantee 0 <= bytes_to_rcv <= rmb_desc->len */
+                smp_mb__after_atomic();
+                smc->sk.sk_data_ready(&smc->sk);
+        } else {
+                if (conn->local_rx_ctrl.prod_flags.write_blocked)
+                        smc->sk.sk_data_ready(&smc->sk);
+                if (conn->local_rx_ctrl.prod_flags.urg_data_pending)
+                        conn->urg_state = SMC_URG_NOTYET;
+        }
+
+        /* trigger sndbuf consumer: RDMA write into peer RMBE and CDC */
+        if ((diff_cons && smc_tx_prepared_sends(conn)) ||
+            conn->local_rx_ctrl.prod_flags.cons_curs_upd_req ||
+            conn->local_rx_ctrl.prod_flags.urg_data_pending)
+                smc_tx_sndbuf_nonempty(conn);
+
+        if (diff_cons && conn->urg_tx_pend &&
+            atomic_read(&conn->peer_rmbe_space) == conn->peer_rmbe_size) {
+                /* urg data confirmed by peer, indicate we're ready for more */
+                conn->urg_tx_pend = false;
+                smc->sk.sk_write_space(&smc->sk);
+        }
+
+        if (conn->local_rx_ctrl.conn_state_flags.peer_conn_abort) {
+                smc->sk.sk_err = ECONNRESET;
+                conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
+        }
+        if (smc_cdc_rxed_any_close_or_senddone(conn)) {
+                smc->sk.sk_shutdown |= RCV_SHUTDOWN;
+                if (smc->clcsock && smc->clcsock->sk)
+                        smc->clcsock->sk->sk_shutdown |= RCV_SHUTDOWN;
+                sock_set_flag(&smc->sk, SOCK_DONE);
+                sock_hold(&smc->sk); /* sock_put in close_work */
+                if (!queue_work(smc_close_wq, &conn->close_work))
+                        sock_put(&smc->sk);
+        }
+}
+
+/* called under tasklet context */
+static void smc_cdc_msg_recv(struct smc_sock *smc, struct smc_cdc_msg *cdc)
+{
+        sock_hold(&smc->sk);
+        bh_lock_sock(&smc->sk);
+        smc_cdc_msg_recv_action(smc, cdc);
+        bh_unlock_sock(&smc->sk);
+        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 *data_cdc;
+        struct smcd_cdc_msg cdc;
+        struct smc_sock *smc;
+
+        if (!conn || conn->killed)
+                return;
+
+        data_cdc = (struct smcd_cdc_msg *)conn->rmb_desc->cpu_addr;
+        smcd_curs_copy(&cdc.prod, &data_cdc->prod, conn);
+        smcd_curs_copy(&cdc.cons, &data_cdc->cons, conn);
+        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)
+{
+        struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
+        struct smc_cdc_msg *cdc = buf;
+        struct smc_connection *conn;
+        struct smc_link_group *lgr;
+        struct smc_sock *smc;
+
+        if (wc->byte_len < offsetof(struct smc_cdc_msg, reserved))
+                return; /* short message */
+        if (cdc->len != SMC_WR_TX_SIZE)
+                return; /* invalid message */
+
+        /* lookup connection */
+        lgr = smc_get_lgr(link);
+        read_lock_bh(&lgr->conns_lock);
+        conn = smc_lgr_find_conn(ntohl(cdc->token), lgr);
+        read_unlock_bh(&lgr->conns_lock);
+        if (!conn || conn->out_of_sync)
+                return;
+        smc = container_of(conn, struct smc_sock, conn);
+
+        if (cdc->prod_flags.failover_validation) {
+                smc_cdc_msg_validate(smc, cdc, link);
+                return;
+        }
+        if (smc_cdc_before(ntohs(cdc->seqno),
+                           conn->local_rx_ctrl.seqno))
+                /* received seqno is old */
+                return;
+
+        smc_cdc_msg_recv(smc, cdc);
+}
+
+static struct smc_wr_rx_handler smc_cdc_rx_handlers[] = {
+        {
+                .handler        = smc_cdc_rx_handler,
+                .type           = SMC_CDC_MSG_TYPE
+        },
+        {
+                .handler        = NULL,
+        }
+};
+
+int __init smc_cdc_init(void)
+{
+        struct smc_wr_rx_handler *handler;
+        int rc = 0;
+
+        for (handler = smc_cdc_rx_handlers; handler->handler; handler++) {
+                INIT_HLIST_NODE(&handler->list);
+                rc = smc_wr_rx_register_handler(handler);
+                if (rc)
+                        break;
+        }
+        return rc;
+}