![Stefan Raspl](/assets/img/avatar_default.png)
Add support for out of band data send and receive. Signed-off-by: Stefan Raspl <raspl@linux.ibm.com> Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
335 lines
9.5 KiB
C
335 lines
9.5 KiB
C
// 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 *************************************/
|
|
|
|
struct smc_cdc_tx_pend {
|
|
struct smc_connection *conn; /* socket connection */
|
|
union smc_host_cursor cursor; /* tx sndbuf cursor sent */
|
|
union smc_host_cursor p_cursor; /* rx RMBE cursor produced */
|
|
u16 ctrl_seq; /* conn. tx sequence # */
|
|
};
|
|
|
|
/* 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_sock *smc;
|
|
int diff;
|
|
|
|
if (!cdcpend->conn)
|
|
/* already dismissed */
|
|
return;
|
|
|
|
smc = container_of(cdcpend->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_write(&cdcpend->conn->tx_curs_fin,
|
|
smc_curs_read(&cdcpend->cursor, cdcpend->conn),
|
|
cdcpend->conn);
|
|
}
|
|
smc_tx_sndbuf_nonfull(smc);
|
|
bh_unlock_sock(&smc->sk);
|
|
}
|
|
|
|
int smc_cdc_get_free_slot(struct smc_connection *conn,
|
|
struct smc_wr_buf **wr_buf,
|
|
struct smc_cdc_tx_pend **pend)
|
|
{
|
|
struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];
|
|
int rc;
|
|
|
|
rc = smc_wr_tx_get_free_slot(link, smc_cdc_tx_handler, wr_buf,
|
|
(struct smc_wr_tx_pend_priv **)pend);
|
|
if (!conn->alert_token_local)
|
|
/* abnormal termination */
|
|
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(
|
|
sizeof(struct smc_cdc_msg) != 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;
|
|
int rc;
|
|
|
|
link = &conn->lgr->lnk[SMC_SINGLE_LINK];
|
|
|
|
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->local_tx_ctrl, conn);
|
|
rc = smc_wr_tx_send(link, (struct smc_wr_tx_pend_priv *)pend);
|
|
if (!rc)
|
|
smc_curs_write(&conn->rx_curs_confirmed,
|
|
smc_curs_read(&conn->local_tx_ctrl.cons, conn),
|
|
conn);
|
|
|
|
return rc;
|
|
}
|
|
|
|
int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
|
|
{
|
|
struct smc_cdc_tx_pend *pend;
|
|
struct smc_wr_buf *wr_buf;
|
|
int rc;
|
|
|
|
rc = smc_cdc_get_free_slot(conn, &wr_buf, &pend);
|
|
if (rc)
|
|
return rc;
|
|
|
|
return smc_cdc_msg_send(conn, wr_buf, pend);
|
|
}
|
|
|
|
static bool smc_cdc_tx_filter(struct smc_wr_tx_pend_priv *tx_pend,
|
|
unsigned long data)
|
|
{
|
|
struct smc_connection *conn = (struct smc_connection *)data;
|
|
struct smc_cdc_tx_pend *cdc_pend =
|
|
(struct smc_cdc_tx_pend *)tx_pend;
|
|
|
|
return cdc_pend->conn == conn;
|
|
}
|
|
|
|
static void smc_cdc_tx_dismisser(struct smc_wr_tx_pend_priv *tx_pend)
|
|
{
|
|
struct smc_cdc_tx_pend *cdc_pend =
|
|
(struct smc_cdc_tx_pend *)tx_pend;
|
|
|
|
cdc_pend->conn = NULL;
|
|
}
|
|
|
|
void smc_cdc_tx_dismiss_slots(struct smc_connection *conn)
|
|
{
|
|
struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];
|
|
|
|
smc_wr_tx_dismiss_slots(link, SMC_CDC_MSG_TYPE,
|
|
smc_cdc_tx_filter, smc_cdc_tx_dismisser,
|
|
(unsigned long)conn);
|
|
}
|
|
|
|
/********************************* 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_write(&conn->urg_curs,
|
|
smc_curs_read(&conn->local_rx_ctrl.prod, conn),
|
|
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;
|
|
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_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_write(&prod_old,
|
|
smc_curs_read(&conn->local_rx_ctrl.prod, conn),
|
|
conn);
|
|
smc_curs_write(&cons_old,
|
|
smc_curs_read(&conn->local_rx_ctrl.cons, conn),
|
|
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 ||
|
|
conn->local_rx_ctrl.prod_flags.cons_curs_upd_req ||
|
|
conn->local_rx_ctrl.prod_flags.urg_data_pending) {
|
|
if (conn->local_rx_ctrl.prod_flags.urg_data_pending)
|
|
conn->urg_state = SMC_URG_NOTYET;
|
|
/* force immediate tx of current consumer cursor, but
|
|
* under send_lock to guarantee arrival in seqno-order
|
|
*/
|
|
smc_tx_sndbuf_nonempty(conn);
|
|
}
|
|
}
|
|
|
|
/* piggy backed tx info */
|
|
/* trigger sndbuf consumer: RDMA write into peer RMBE and CDC */
|
|
if (diff_cons && smc_tx_prepared_sends(conn)) {
|
|
smc_tx_sndbuf_nonempty(conn);
|
|
/* trigger socket release if connection closed */
|
|
smc_close_wake_tx_prepared(smc);
|
|
}
|
|
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 (!schedule_work(&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 */
|
|
}
|
|
|
|
/***************************** 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 = container_of(link, struct smc_link_group, lnk[SMC_SINGLE_LINK]);
|
|
read_lock_bh(&lgr->conns_lock);
|
|
conn = smc_lgr_find_conn(ntohl(cdc->token), lgr);
|
|
read_unlock_bh(&lgr->conns_lock);
|
|
if (!conn)
|
|
return;
|
|
smc = container_of(conn, struct smc_sock, conn);
|
|
|
|
if (!cdc->prod_flags.failover_validation) {
|
|
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;
|
|
}
|