X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=net%2Fkcm%2Fkcmsock.c;h=b7f869a85ab7dadae7874bd1e3339b20c391d58f;hb=b20b378d49926b82c0a131492fa8842156e0e8a9;hp=cb39e05b166cf5eaa0729b775f3ee0b8a140398a;hpb=0cbbc422d56668528f6efd1234fe908010284082;p=cascardo%2Flinux.git diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index cb39e05b166c..b7f869a85ab7 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1,3 +1,13 @@ +/* + * Kernel Connection Multiplexor + * + * Copyright (c) 2016 Tom Herbert + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + */ + #include #include #include @@ -13,10 +23,10 @@ #include #include #include +#include #include #include #include -#include #include unsigned int kcm_net_id; @@ -35,38 +45,12 @@ static inline struct kcm_tx_msg *kcm_tx_msg(struct sk_buff *skb) return (struct kcm_tx_msg *)skb->cb; } -static inline struct kcm_rx_msg *kcm_rx_msg(struct sk_buff *skb) -{ - return (struct kcm_rx_msg *)((void *)skb->cb + - offsetof(struct qdisc_skb_cb, data)); -} - static void report_csk_error(struct sock *csk, int err) { csk->sk_err = EPIPE; csk->sk_error_report(csk); } -/* Callback lock held */ -static void kcm_abort_rx_psock(struct kcm_psock *psock, int err, - struct sk_buff *skb) -{ - struct sock *csk = psock->sk; - - /* Unrecoverable error in receive */ - - del_timer(&psock->rx_msg_timer); - - if (psock->rx_stopped) - return; - - psock->rx_stopped = 1; - KCM_STATS_INCR(psock->stats.rx_aborts); - - /* Report an error on the lower socket */ - report_csk_error(csk, err); -} - static void kcm_abort_tx_psock(struct kcm_psock *psock, int err, bool wakeup_kcm) { @@ -109,12 +93,13 @@ static void kcm_abort_tx_psock(struct kcm_psock *psock, int err, static void kcm_update_rx_mux_stats(struct kcm_mux *mux, struct kcm_psock *psock) { - KCM_STATS_ADD(mux->stats.rx_bytes, - psock->stats.rx_bytes - psock->saved_rx_bytes); + STRP_STATS_ADD(mux->stats.rx_bytes, + psock->strp.stats.rx_bytes - + psock->saved_rx_bytes); mux->stats.rx_msgs += - psock->stats.rx_msgs - psock->saved_rx_msgs; - psock->saved_rx_msgs = psock->stats.rx_msgs; - psock->saved_rx_bytes = psock->stats.rx_bytes; + psock->strp.stats.rx_msgs - psock->saved_rx_msgs; + psock->saved_rx_msgs = psock->strp.stats.rx_msgs; + psock->saved_rx_bytes = psock->strp.stats.rx_bytes; } static void kcm_update_tx_mux_stats(struct kcm_mux *mux, @@ -167,11 +152,11 @@ static void kcm_rcv_ready(struct kcm_sock *kcm) */ list_del(&psock->psock_ready_list); psock->ready_rx_msg = NULL; - /* Commit clearing of ready_rx_msg for queuing work */ smp_mb(); - queue_work(kcm_wq, &psock->rx_work); + strp_unpause(&psock->strp); + strp_check_rcv(&psock->strp); } /* Buffer limit is okay now, add to ready list */ @@ -285,6 +270,7 @@ static struct kcm_sock *reserve_rx_kcm(struct kcm_psock *psock, if (list_empty(&mux->kcm_rx_waiters)) { psock->ready_rx_msg = head; + strp_pause(&psock->strp); list_add_tail(&psock->psock_ready_list, &mux->psocks_ready); spin_unlock_bh(&mux->rx_lock); @@ -353,346 +339,60 @@ static void unreserve_rx_kcm(struct kcm_psock *psock, spin_unlock_bh(&mux->rx_lock); } -static void kcm_start_rx_timer(struct kcm_psock *psock) -{ - if (psock->sk->sk_rcvtimeo) - mod_timer(&psock->rx_msg_timer, psock->sk->sk_rcvtimeo); -} - -/* Macro to invoke filter function. */ -#define KCM_RUN_FILTER(prog, ctx) \ - (*prog->bpf_func)(ctx, prog->insnsi) - -/* Lower socket lock held */ -static int kcm_tcp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb, - unsigned int orig_offset, size_t orig_len) -{ - struct kcm_psock *psock = (struct kcm_psock *)desc->arg.data; - struct kcm_rx_msg *rxm; - struct kcm_sock *kcm; - struct sk_buff *head, *skb; - size_t eaten = 0, cand_len; - ssize_t extra; - int err; - bool cloned_orig = false; - - if (psock->ready_rx_msg) - return 0; - - head = psock->rx_skb_head; - if (head) { - /* Message already in progress */ - - rxm = kcm_rx_msg(head); - if (unlikely(rxm->early_eaten)) { - /* Already some number of bytes on the receive sock - * data saved in rx_skb_head, just indicate they - * are consumed. - */ - eaten = orig_len <= rxm->early_eaten ? - orig_len : rxm->early_eaten; - rxm->early_eaten -= eaten; - - return eaten; - } - - if (unlikely(orig_offset)) { - /* Getting data with a non-zero offset when a message is - * in progress is not expected. If it does happen, we - * need to clone and pull since we can't deal with - * offsets in the skbs for a message expect in the head. - */ - orig_skb = skb_clone(orig_skb, GFP_ATOMIC); - if (!orig_skb) { - KCM_STATS_INCR(psock->stats.rx_mem_fail); - desc->error = -ENOMEM; - return 0; - } - if (!pskb_pull(orig_skb, orig_offset)) { - KCM_STATS_INCR(psock->stats.rx_mem_fail); - kfree_skb(orig_skb); - desc->error = -ENOMEM; - return 0; - } - cloned_orig = true; - orig_offset = 0; - } - - if (!psock->rx_skb_nextp) { - /* We are going to append to the frags_list of head. - * Need to unshare the frag_list. - */ - err = skb_unclone(head, GFP_ATOMIC); - if (err) { - KCM_STATS_INCR(psock->stats.rx_mem_fail); - desc->error = err; - return 0; - } - - if (unlikely(skb_shinfo(head)->frag_list)) { - /* We can't append to an sk_buff that already - * has a frag_list. We create a new head, point - * the frag_list of that to the old head, and - * then are able to use the old head->next for - * appending to the message. - */ - if (WARN_ON(head->next)) { - desc->error = -EINVAL; - return 0; - } - - skb = alloc_skb(0, GFP_ATOMIC); - if (!skb) { - KCM_STATS_INCR(psock->stats.rx_mem_fail); - desc->error = -ENOMEM; - return 0; - } - skb->len = head->len; - skb->data_len = head->len; - skb->truesize = head->truesize; - *kcm_rx_msg(skb) = *kcm_rx_msg(head); - psock->rx_skb_nextp = &head->next; - skb_shinfo(skb)->frag_list = head; - psock->rx_skb_head = skb; - head = skb; - } else { - psock->rx_skb_nextp = - &skb_shinfo(head)->frag_list; - } - } - } - - while (eaten < orig_len) { - /* Always clone since we will consume something */ - skb = skb_clone(orig_skb, GFP_ATOMIC); - if (!skb) { - KCM_STATS_INCR(psock->stats.rx_mem_fail); - desc->error = -ENOMEM; - break; - } - - cand_len = orig_len - eaten; - - head = psock->rx_skb_head; - if (!head) { - head = skb; - psock->rx_skb_head = head; - /* Will set rx_skb_nextp on next packet if needed */ - psock->rx_skb_nextp = NULL; - rxm = kcm_rx_msg(head); - memset(rxm, 0, sizeof(*rxm)); - rxm->offset = orig_offset + eaten; - } else { - /* Unclone since we may be appending to an skb that we - * already share a frag_list with. - */ - err = skb_unclone(skb, GFP_ATOMIC); - if (err) { - KCM_STATS_INCR(psock->stats.rx_mem_fail); - desc->error = err; - break; - } - - rxm = kcm_rx_msg(head); - *psock->rx_skb_nextp = skb; - psock->rx_skb_nextp = &skb->next; - head->data_len += skb->len; - head->len += skb->len; - head->truesize += skb->truesize; - } - - if (!rxm->full_len) { - ssize_t len; - - len = KCM_RUN_FILTER(psock->bpf_prog, head); - - if (!len) { - /* Need more header to determine length */ - if (!rxm->accum_len) { - /* Start RX timer for new message */ - kcm_start_rx_timer(psock); - } - rxm->accum_len += cand_len; - eaten += cand_len; - KCM_STATS_INCR(psock->stats.rx_need_more_hdr); - WARN_ON(eaten != orig_len); - break; - } else if (len > psock->sk->sk_rcvbuf) { - /* Message length exceeds maximum allowed */ - KCM_STATS_INCR(psock->stats.rx_msg_too_big); - desc->error = -EMSGSIZE; - psock->rx_skb_head = NULL; - kcm_abort_rx_psock(psock, EMSGSIZE, head); - break; - } else if (len <= (ssize_t)head->len - - skb->len - rxm->offset) { - /* Length must be into new skb (and also - * greater than zero) - */ - KCM_STATS_INCR(psock->stats.rx_bad_hdr_len); - desc->error = -EPROTO; - psock->rx_skb_head = NULL; - kcm_abort_rx_psock(psock, EPROTO, head); - break; - } - - rxm->full_len = len; - } - - extra = (ssize_t)(rxm->accum_len + cand_len) - rxm->full_len; - - if (extra < 0) { - /* Message not complete yet. */ - if (rxm->full_len - rxm->accum_len > - tcp_inq(psock->sk)) { - /* Don't have the whole messages in the socket - * buffer. Set psock->rx_need_bytes to wait for - * the rest of the message. Also, set "early - * eaten" since we've already buffered the skb - * but don't consume yet per tcp_read_sock. - */ - - if (!rxm->accum_len) { - /* Start RX timer for new message */ - kcm_start_rx_timer(psock); - } - - psock->rx_need_bytes = rxm->full_len - - rxm->accum_len; - rxm->accum_len += cand_len; - rxm->early_eaten = cand_len; - KCM_STATS_ADD(psock->stats.rx_bytes, cand_len); - desc->count = 0; /* Stop reading socket */ - break; - } - rxm->accum_len += cand_len; - eaten += cand_len; - WARN_ON(eaten != orig_len); - break; - } - - /* Positive extra indicates ore bytes than needed for the - * message - */ - - WARN_ON(extra > cand_len); - - eaten += (cand_len - extra); - - /* Hurray, we have a new message! */ - del_timer(&psock->rx_msg_timer); - psock->rx_skb_head = NULL; - KCM_STATS_INCR(psock->stats.rx_msgs); - -try_queue: - kcm = reserve_rx_kcm(psock, head); - if (!kcm) { - /* Unable to reserve a KCM, message is held in psock. */ - break; - } - - if (kcm_queue_rcv_skb(&kcm->sk, head)) { - /* Should mean socket buffer full */ - unreserve_rx_kcm(psock, false); - goto try_queue; - } - } - - if (cloned_orig) - kfree_skb(orig_skb); - - KCM_STATS_ADD(psock->stats.rx_bytes, eaten); - - return eaten; -} - -/* Called with lock held on lower socket */ -static int psock_tcp_read_sock(struct kcm_psock *psock) -{ - read_descriptor_t desc; - - desc.arg.data = psock; - desc.error = 0; - desc.count = 1; /* give more than one skb per call */ - - /* sk should be locked here, so okay to do tcp_read_sock */ - tcp_read_sock(psock->sk, &desc, kcm_tcp_recv); - - unreserve_rx_kcm(psock, true); - - return desc.error; -} - /* Lower sock lock held */ -static void psock_tcp_data_ready(struct sock *sk) +static void psock_data_ready(struct sock *sk) { struct kcm_psock *psock; read_lock_bh(&sk->sk_callback_lock); psock = (struct kcm_psock *)sk->sk_user_data; - if (unlikely(!psock || psock->rx_stopped)) - goto out; + if (likely(psock)) + strp_data_ready(&psock->strp); - if (psock->ready_rx_msg) - goto out; - - if (psock->rx_need_bytes) { - if (tcp_inq(sk) >= psock->rx_need_bytes) - psock->rx_need_bytes = 0; - else - goto out; - } - - if (psock_tcp_read_sock(psock) == -ENOMEM) - queue_delayed_work(kcm_wq, &psock->rx_delayed_work, 0); - -out: read_unlock_bh(&sk->sk_callback_lock); } -static void do_psock_rx_work(struct kcm_psock *psock) +/* Called with lower sock held */ +static void kcm_rcv_strparser(struct strparser *strp, struct sk_buff *skb) { - read_descriptor_t rd_desc; - struct sock *csk = psock->sk; - - /* We need the read lock to synchronize with psock_tcp_data_ready. We - * need the socket lock for calling tcp_read_sock. - */ - lock_sock(csk); - read_lock_bh(&csk->sk_callback_lock); - - if (unlikely(csk->sk_user_data != psock)) - goto out; - - if (unlikely(psock->rx_stopped)) - goto out; - - if (psock->ready_rx_msg) - goto out; - - rd_desc.arg.data = psock; + struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp); + struct kcm_sock *kcm; - if (psock_tcp_read_sock(psock) == -ENOMEM) - queue_delayed_work(kcm_wq, &psock->rx_delayed_work, 0); +try_queue: + kcm = reserve_rx_kcm(psock, skb); + if (!kcm) { + /* Unable to reserve a KCM, message is held in psock and strp + * is paused. + */ + return; + } -out: - read_unlock_bh(&csk->sk_callback_lock); - release_sock(csk); + if (kcm_queue_rcv_skb(&kcm->sk, skb)) { + /* Should mean socket buffer full */ + unreserve_rx_kcm(psock, false); + goto try_queue; + } } -static void psock_rx_work(struct work_struct *w) +static int kcm_parse_func_strparser(struct strparser *strp, struct sk_buff *skb) { - do_psock_rx_work(container_of(w, struct kcm_psock, rx_work)); + struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp); + struct bpf_prog *prog = psock->bpf_prog; + + return (*prog->bpf_func)(skb, prog->insnsi); } -static void psock_rx_delayed_work(struct work_struct *w) +static int kcm_read_sock_done(struct strparser *strp, int err) { - do_psock_rx_work(container_of(w, struct kcm_psock, - rx_delayed_work.work)); + struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp); + + unreserve_rx_kcm(psock, true); + + return err; } -static void psock_tcp_state_change(struct sock *sk) +static void psock_state_change(struct sock *sk) { /* TCP only does a POLLIN for a half close. Do a POLLHUP here * since application will normally not poll with POLLIN @@ -702,7 +402,7 @@ static void psock_tcp_state_change(struct sock *sk) report_csk_error(sk, EPIPE); } -static void psock_tcp_write_space(struct sock *sk) +static void psock_write_space(struct sock *sk) { struct kcm_psock *psock; struct kcm_mux *mux; @@ -713,14 +413,13 @@ static void psock_tcp_write_space(struct sock *sk) psock = (struct kcm_psock *)sk->sk_user_data; if (unlikely(!psock)) goto out; - mux = psock->mux; spin_lock_bh(&mux->lock); /* Check if the socket is reserved so someone is waiting for sending. */ kcm = psock->tx_kcm; - if (kcm) + if (kcm && !unlikely(kcm->tx_stopped)) queue_work(kcm_wq, &kcm->tx_work); spin_unlock_bh(&mux->lock); @@ -1411,7 +1110,7 @@ static int kcm_recvmsg(struct socket *sock, struct msghdr *msg, struct kcm_sock *kcm = kcm_sk(sk); int err = 0; long timeo; - struct kcm_rx_msg *rxm; + struct strp_rx_msg *rxm; int copied = 0; struct sk_buff *skb; @@ -1425,7 +1124,7 @@ static int kcm_recvmsg(struct socket *sock, struct msghdr *msg, /* Okay, have a message on the receive queue */ - rxm = kcm_rx_msg(skb); + rxm = strp_rx_msg(skb); if (len > rxm->full_len) len = rxm->full_len; @@ -1481,7 +1180,7 @@ static ssize_t kcm_splice_read(struct socket *sock, loff_t *ppos, struct sock *sk = sock->sk; struct kcm_sock *kcm = kcm_sk(sk); long timeo; - struct kcm_rx_msg *rxm; + struct strp_rx_msg *rxm; int err = 0; ssize_t copied; struct sk_buff *skb; @@ -1498,7 +1197,7 @@ static ssize_t kcm_splice_read(struct socket *sock, loff_t *ppos, /* Okay, have a message on the receive queue */ - rxm = kcm_rx_msg(skb); + rxm = strp_rx_msg(skb); if (len > rxm->full_len) len = rxm->full_len; @@ -1674,15 +1373,6 @@ static void init_kcm_sock(struct kcm_sock *kcm, struct kcm_mux *mux) spin_unlock_bh(&mux->rx_lock); } -static void kcm_rx_msg_timeout(unsigned long arg) -{ - struct kcm_psock *psock = (struct kcm_psock *)arg; - - /* Message assembly timed out */ - KCM_STATS_INCR(psock->stats.rx_msg_timeouts); - kcm_abort_rx_psock(psock, ETIMEDOUT, NULL); -} - static int kcm_attach(struct socket *sock, struct socket *csock, struct bpf_prog *prog) { @@ -1692,19 +1382,13 @@ static int kcm_attach(struct socket *sock, struct socket *csock, struct kcm_psock *psock = NULL, *tpsock; struct list_head *head; int index = 0; - - if (csock->ops->family != PF_INET && - csock->ops->family != PF_INET6) - return -EINVAL; + struct strp_callbacks cb; + int err; csk = csock->sk; if (!csk) return -EINVAL; - /* Only support TCP for now */ - if (csk->sk_protocol != IPPROTO_TCP) - return -EINVAL; - psock = kmem_cache_zalloc(kcm_psockp, GFP_KERNEL); if (!psock) return -ENOMEM; @@ -1713,11 +1397,16 @@ static int kcm_attach(struct socket *sock, struct socket *csock, psock->sk = csk; psock->bpf_prog = prog; - setup_timer(&psock->rx_msg_timer, kcm_rx_msg_timeout, - (unsigned long)psock); + cb.rcv_msg = kcm_rcv_strparser; + cb.abort_parser = NULL; + cb.parse_msg = kcm_parse_func_strparser; + cb.read_sock_done = kcm_read_sock_done; - INIT_WORK(&psock->rx_work, psock_rx_work); - INIT_DELAYED_WORK(&psock->rx_delayed_work, psock_rx_delayed_work); + err = strp_init(&psock->strp, csk, &cb); + if (err) { + kmem_cache_free(kcm_psockp, psock); + return err; + } sock_hold(csk); @@ -1726,9 +1415,9 @@ static int kcm_attach(struct socket *sock, struct socket *csock, psock->save_write_space = csk->sk_write_space; psock->save_state_change = csk->sk_state_change; csk->sk_user_data = psock; - csk->sk_data_ready = psock_tcp_data_ready; - csk->sk_write_space = psock_tcp_write_space; - csk->sk_state_change = psock_tcp_state_change; + csk->sk_data_ready = psock_data_ready; + csk->sk_write_space = psock_write_space; + csk->sk_state_change = psock_state_change; write_unlock_bh(&csk->sk_callback_lock); /* Finished initialization, now add the psock to the MUX. */ @@ -1750,7 +1439,7 @@ static int kcm_attach(struct socket *sock, struct socket *csock, spin_unlock_bh(&mux->lock); /* Schedule RX work in case there are already bytes queued */ - queue_work(kcm_wq, &psock->rx_work); + strp_check_rcv(&psock->strp); return 0; } @@ -1790,6 +1479,8 @@ static void kcm_unattach(struct kcm_psock *psock) struct sock *csk = psock->sk; struct kcm_mux *mux = psock->mux; + lock_sock(csk); + /* Stop getting callbacks from TCP socket. After this there should * be no way to reserve a kcm for this psock. */ @@ -1798,7 +1489,7 @@ static void kcm_unattach(struct kcm_psock *psock) csk->sk_data_ready = psock->save_data_ready; csk->sk_write_space = psock->save_write_space; csk->sk_state_change = psock->save_state_change; - psock->rx_stopped = 1; + strp_stop(&psock->strp); if (WARN_ON(psock->rx_kcm)) { write_unlock_bh(&csk->sk_callback_lock); @@ -1821,18 +1512,17 @@ static void kcm_unattach(struct kcm_psock *psock) write_unlock_bh(&csk->sk_callback_lock); - del_timer_sync(&psock->rx_msg_timer); - cancel_work_sync(&psock->rx_work); - cancel_delayed_work_sync(&psock->rx_delayed_work); + /* Call strp_done without sock lock */ + release_sock(csk); + strp_done(&psock->strp); + lock_sock(csk); bpf_prog_put(psock->bpf_prog); - kfree_skb(psock->rx_skb_head); - psock->rx_skb_head = NULL; - spin_lock_bh(&mux->lock); aggregate_psock_stats(&psock->stats, &mux->aggregate_psock_stats); + save_strp_stats(&psock->strp, &mux->aggregate_strp_stats); KCM_STATS_INCR(mux->stats.psock_unattach); @@ -1875,6 +1565,8 @@ no_reserved: fput(csk->sk_socket->file); kmem_cache_free(kcm_psockp, psock); } + + release_sock(csk); } static int kcm_unattach_ioctl(struct socket *sock, struct kcm_unattach *info) @@ -1915,6 +1607,7 @@ static int kcm_unattach_ioctl(struct socket *sock, struct kcm_unattach *info) spin_unlock_bh(&mux->lock); + /* Lower socket lock should already be held */ kcm_unattach(psock); err = 0; @@ -2029,7 +1722,7 @@ static int kcm_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) if (copy_to_user((void __user *)arg, &info, sizeof(info))) { err = -EFAULT; - sock_release(newsock); + sys_close(info.fd); } } @@ -2072,6 +1765,8 @@ static void release_mux(struct kcm_mux *mux) aggregate_mux_stats(&mux->stats, &knet->aggregate_mux_stats); aggregate_psock_stats(&mux->aggregate_psock_stats, &knet->aggregate_psock_stats); + aggregate_strp_stats(&mux->aggregate_strp_stats, + &knet->aggregate_strp_stats); list_del_rcu(&mux->kcm_mux_list); knet->count--; mutex_unlock(&knet->mutex); @@ -2151,6 +1846,13 @@ static int kcm_release(struct socket *sock) * it will just return. */ __skb_queue_purge(&sk->sk_write_queue); + + /* Set tx_stopped. This is checked when psock is bound to a kcm and we + * get a writespace callback. This prevents further work being queued + * from the callback (unbinding the psock occurs after canceling work. + */ + kcm->tx_stopped = 1; + release_sock(sk); spin_lock_bh(&mux->lock);