diff options
| -rw-r--r-- | net/smc/af_smc.c | 38 | ||||
| -rw-r--r-- | net/smc/smc.h | 3 | ||||
| -rw-r--r-- | net/smc/smc_rx.c | 163 | ||||
| -rw-r--r-- | net/smc/smc_rx.h | 6 |
4 files changed, 185 insertions, 25 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index a7495c84ae15..17688a02035b 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -1163,10 +1163,12 @@ static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, goto out; } - if (smc->use_fallback) + if (smc->use_fallback) { rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags); - else - rc = smc_rx_recvmsg(smc, msg, len, flags); + } else { + msg->msg_namelen = 0; + rc = smc_rx_recvmsg(smc, msg, NULL, len, flags); + } out: release_sock(sk); @@ -1447,9 +1449,15 @@ out: return rc; } +/* Map the affected portions of the rmbe into an spd, note the number of bytes + * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor + * updates till whenever a respective page has been fully processed. + * Note that subsequent recv() calls have to wait till all splice() processing + * completed. + */ static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, - unsigned int flags) + unsigned int flags) { struct sock *sk = sock->sk; struct smc_sock *smc; @@ -1457,16 +1465,34 @@ static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos, smc = smc_sk(sk); lock_sock(sk); - if ((sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_CLOSED)) + + if (sk->sk_state == SMC_INIT || + sk->sk_state == SMC_LISTEN || + sk->sk_state == SMC_CLOSED) + goto out; + + if (sk->sk_state == SMC_PEERFINCLOSEWAIT) { + rc = 0; goto out; + } + if (smc->use_fallback) { rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos, pipe, len, flags); } else { - rc = -EOPNOTSUPP; + if (*ppos) { + rc = -ESPIPE; + goto out; + } + if (flags & SPLICE_F_NONBLOCK) + flags = MSG_DONTWAIT; + else + flags = 0; + rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags); } out: release_sock(sk); + return rc; } diff --git a/net/smc/smc.h b/net/smc/smc.h index 2405e889b93d..ec209cd48d42 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -164,6 +164,9 @@ struct smc_connection { atomic_t bytes_to_rcv; /* arrived data, * not yet received */ + atomic_t splice_pending; /* number of spliced bytes + * pending processing + */ #ifndef KERNEL_HAS_ATOMIC64 spinlock_t acurs_lock; /* protect cursors */ #endif diff --git a/net/smc/smc_rx.c b/net/smc/smc_rx.c index 7b64bee656e8..ed45569289f5 100644 --- a/net/smc/smc_rx.c +++ b/net/smc/smc_rx.c @@ -43,6 +43,116 @@ static void smc_rx_wake_up(struct sock *sk) rcu_read_unlock(); } +/* Update consumer cursor + * @conn connection to update + * @cons consumer cursor + * @len number of Bytes consumed + */ +static void smc_rx_update_consumer(struct smc_connection *conn, + union smc_host_cursor cons, size_t len) +{ + smc_curs_add(conn->rmbe_size, &cons, len); + smc_curs_write(&conn->local_tx_ctrl.cons, smc_curs_read(&cons, conn), + conn); + /* send consumer cursor update if required */ + /* similar to advertising new TCP rcv_wnd if required */ + smc_tx_consumer_update(conn); +} + +struct smc_spd_priv { + struct smc_sock *smc; + size_t len; +}; + +static void smc_rx_pipe_buf_release(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) +{ + struct smc_spd_priv *priv = (struct smc_spd_priv *)buf->private; + struct smc_sock *smc = priv->smc; + struct smc_connection *conn; + union smc_host_cursor cons; + struct sock *sk = &smc->sk; + + if (sk->sk_state == SMC_CLOSED || + sk->sk_state == SMC_PEERFINCLOSEWAIT || + sk->sk_state == SMC_APPFINCLOSEWAIT) + goto out; + conn = &smc->conn; + lock_sock(sk); + smc_curs_write(&cons, smc_curs_read(&conn->local_tx_ctrl.cons, conn), + conn); + smc_rx_update_consumer(conn, cons, priv->len); + release_sock(sk); + if (atomic_sub_and_test(priv->len, &conn->splice_pending)) + smc_rx_wake_up(sk); +out: + kfree(priv); + put_page(buf->page); + sock_put(sk); +} + +static int smc_rx_pipe_buf_nosteal(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) +{ + return 1; +} + +static const struct pipe_buf_operations smc_pipe_ops = { + .can_merge = 0, + .confirm = generic_pipe_buf_confirm, + .release = smc_rx_pipe_buf_release, + .steal = smc_rx_pipe_buf_nosteal, + .get = generic_pipe_buf_get +}; + +static void smc_rx_spd_release(struct splice_pipe_desc *spd, + unsigned int i) +{ + put_page(spd->pages[i]); +} + +static int smc_rx_splice(struct pipe_inode_info *pipe, char *src, size_t len, + struct smc_sock *smc) +{ + struct splice_pipe_desc spd; + struct partial_page partial; + struct smc_spd_priv *priv; + struct page *page; + int bytes; + + page = virt_to_page(smc->conn.rmb_desc->cpu_addr); + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + priv->len = len; + priv->smc = smc; + partial.offset = src - (char *)smc->conn.rmb_desc->cpu_addr; + partial.len = len; + partial.private = (unsigned long)priv; + + spd.nr_pages_max = 1; + spd.nr_pages = 1; + spd.pages = &page; + spd.partial = &partial; + spd.ops = &smc_pipe_ops; + spd.spd_release = smc_rx_spd_release; + + bytes = splice_to_pipe(pipe, &spd); + if (bytes > 0) { + sock_hold(&smc->sk); + get_page(smc->conn.rmb_desc->pages); + atomic_add(bytes, &smc->conn.splice_pending); + } + + return bytes; +} + +static int smc_rx_data_available_and_no_splice_pend(struct smc_connection *conn) +{ + return atomic_read(&conn->bytes_to_rcv) && + !atomic_read(&conn->splice_pending); +} + /* blocks rcvbuf consumer until >=len bytes available or timeout or interrupted * @smc smc socket * @timeo pointer to max seconds to wait, pointer to value 0 for no timeout @@ -74,19 +184,25 @@ int smc_rx_wait(struct smc_sock *smc, long *timeo, return rc; } -/* rcvbuf consumer: main API called by socket layer. - * called under sk lock. +/* smc_rx_recvmsg - receive data from RMBE + * @msg: copy data to receive buffer + * @pipe: copy data to pipe if set - indicates splice() call + * + * rcvbuf consumer: main API called by socket layer. + * Called under sk lock. */ -int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg, size_t len, - int flags) +int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg, + struct pipe_inode_info *pipe, size_t len, int flags) { size_t copylen, read_done = 0, read_remaining = len; size_t chunk_len, chunk_off, chunk_len_sum; struct smc_connection *conn = &smc->conn; + int (*func)(struct smc_connection *conn); union smc_host_cursor cons; int readable, chunk; char *rcvbuf_base; struct sock *sk; + int splbytes; long timeo; int target; /* Read at least these many bytes */ int rc; @@ -102,12 +218,11 @@ int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg, size_t len, timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); - msg->msg_namelen = 0; /* we currently use 1 RMBE per RMB, so RMBE == RMB base addr */ rcvbuf_base = conn->rmb_desc->cpu_addr; do { /* while (read_remaining) */ - if (read_done >= target) + if (read_done >= target || (pipe && read_done)) break; if (atomic_read(&conn->bytes_to_rcv)) @@ -156,11 +271,24 @@ copy: /* initialize variables for 1st iteration of subsequent loop */ /* could be just 1 byte, even after waiting on data above */ readable = atomic_read(&conn->bytes_to_rcv); + splbytes = atomic_read(&conn->splice_pending); + if (!readable || (msg && splbytes)) { + if (splbytes) + func = smc_rx_data_available_and_no_splice_pend; + else + func = smc_rx_data_available; + smc_rx_wait(smc, &timeo, func); + continue; + } + /* not more than what user space asked for */ copylen = min_t(size_t, read_remaining, readable); smc_curs_write(&cons, smc_curs_read(&conn->local_tx_ctrl.cons, conn), conn); + /* subsequent splice() calls pick up where previous left */ + if (splbytes) + smc_curs_add(conn->rmbe_size, &cons, splbytes); /* determine chunks where to read from rcvbuf */ /* either unwrapped case, or 1st chunk of wrapped case */ chunk_len = min_t(size_t, @@ -170,9 +298,16 @@ copy: smc_rmb_sync_sg_for_cpu(conn); for (chunk = 0; chunk < 2; chunk++) { if (!(flags & MSG_TRUNC)) { - rc = memcpy_to_msg(msg, rcvbuf_base + chunk_off, - chunk_len); - if (rc) { + if (msg) { + rc = memcpy_to_msg(msg, rcvbuf_base + + chunk_off, + chunk_len); + } else { + rc = smc_rx_splice(pipe, rcvbuf_base + + chunk_off, chunk_len, + smc); + } + if (rc < 0) { if (!read_done) read_done = -EFAULT; smc_rmb_sync_sg_for_device(conn); @@ -193,18 +328,13 @@ copy: /* update cursors */ if (!(flags & MSG_PEEK)) { - smc_curs_add(conn->rmbe_size, &cons, copylen); /* increased in recv tasklet smc_cdc_msg_rcv() */ smp_mb__before_atomic(); atomic_sub(copylen, &conn->bytes_to_rcv); /* guarantee 0 <= bytes_to_rcv <= rmbe_size */ smp_mb__after_atomic(); - smc_curs_write(&conn->local_tx_ctrl.cons, - smc_curs_read(&cons, conn), - conn); - /* send consumer cursor update if required */ - /* similar to advertising new TCP rcv_wnd if required */ - smc_tx_consumer_update(conn); + if (msg) + smc_rx_update_consumer(conn, cons, copylen); } } while (read_remaining); out: @@ -215,4 +345,5 @@ out: void smc_rx_init(struct smc_sock *smc) { smc->sk.sk_data_ready = smc_rx_wake_up; + atomic_set(&smc->conn.splice_pending, 0); } diff --git a/net/smc/smc_rx.h b/net/smc/smc_rx.h index 8f9f00997641..db823c97d824 100644 --- a/net/smc/smc_rx.h +++ b/net/smc/smc_rx.h @@ -18,8 +18,9 @@ #include "smc.h" void smc_rx_init(struct smc_sock *smc); -int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg, size_t len, - int flags); + +int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg, + struct pipe_inode_info *pipe, size_t len, int flags); int smc_rx_wait(struct smc_sock *smc, long *timeo, int (*fcrit)(struct smc_connection *conn)); static inline int smc_rx_data_available(struct smc_connection *conn) @@ -27,5 +28,4 @@ static inline int smc_rx_data_available(struct smc_connection *conn) return atomic_read(&conn->bytes_to_rcv); } - #endif /* SMC_RX_H */ |