diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c index 13cfa815732d..58e79e02f217 100644 --- a/sound/core/seq/seq_clientmgr.c +++ b/sound/core/seq/seq_clientmgr.c @@ -678,6 +678,9 @@ static int deliver_to_subscribers(struct snd_seq_client *client, else down_read(&grp->list_mutex); list_for_each_entry(subs, &grp->list_head, src_list) { + /* both ports ready? */ + if (atomic_read(&subs->ref_count) != 2) + continue; event->dest = subs->info.dest; if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP) /* convert time according to flag with subscription */ diff --git a/sound/core/seq/seq_ports.c b/sound/core/seq/seq_ports.c index 55170a20ae72..921fb2bd8fad 100644 --- a/sound/core/seq/seq_ports.c +++ b/sound/core/seq/seq_ports.c @@ -173,10 +173,6 @@ struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client, } /* */ -enum group_type { - SRC_LIST, DEST_LIST -}; - static int subscribe_port(struct snd_seq_client *client, struct snd_seq_client_port *port, struct snd_seq_port_subs_info *grp, @@ -203,6 +199,20 @@ static struct snd_seq_client_port *get_client_port(struct snd_seq_addr *addr, return NULL; } +static void delete_and_unsubscribe_port(struct snd_seq_client *client, + struct snd_seq_client_port *port, + struct snd_seq_subscribers *subs, + bool is_src, bool ack); + +static inline struct snd_seq_subscribers * +get_subscriber(struct list_head *p, bool is_src) +{ + if (is_src) + return list_entry(p, struct snd_seq_subscribers, src_list); + else + return list_entry(p, struct snd_seq_subscribers, dest_list); +} + /* * remove all subscribers on the list * this is called from port_delete, for each src and dest list. @@ -210,7 +220,7 @@ static struct snd_seq_client_port *get_client_port(struct snd_seq_addr *addr, static void clear_subscriber_list(struct snd_seq_client *client, struct snd_seq_client_port *port, struct snd_seq_port_subs_info *grp, - int grptype) + int is_src) { struct list_head *p, *n; @@ -219,15 +229,13 @@ static void clear_subscriber_list(struct snd_seq_client *client, struct snd_seq_client *c; struct snd_seq_client_port *aport; - if (grptype == SRC_LIST) { - subs = list_entry(p, struct snd_seq_subscribers, src_list); + subs = get_subscriber(p, is_src); + if (is_src) aport = get_client_port(&subs->info.dest, &c); - } else { - subs = list_entry(p, struct snd_seq_subscribers, dest_list); + else aport = get_client_port(&subs->info.sender, &c); - } - list_del(p); - unsubscribe_port(client, port, grp, &subs->info, 0); + delete_and_unsubscribe_port(client, port, subs, is_src, false); + if (!aport) { /* looks like the connected port is being deleted. * we decrease the counter, and when both ports are deleted @@ -235,21 +243,14 @@ static void clear_subscriber_list(struct snd_seq_client *client, */ if (atomic_dec_and_test(&subs->ref_count)) kfree(subs); - } else { - /* ok we got the connected port */ - struct snd_seq_port_subs_info *agrp; - agrp = (grptype == SRC_LIST) ? &aport->c_dest : &aport->c_src; - down_write(&agrp->list_mutex); - if (grptype == SRC_LIST) - list_del(&subs->dest_list); - else - list_del(&subs->src_list); - up_write(&agrp->list_mutex); - unsubscribe_port(c, aport, agrp, &subs->info, 1); - kfree(subs); - snd_seq_port_unlock(aport); - snd_seq_client_unlock(c); + continue; } + + /* ok we got the connected port */ + delete_and_unsubscribe_port(c, aport, subs, !is_src, true); + kfree(subs); + snd_seq_port_unlock(aport); + snd_seq_client_unlock(c); } } @@ -262,8 +263,8 @@ static int port_delete(struct snd_seq_client *client, snd_use_lock_sync(&port->use_lock); /* clear subscribers info */ - clear_subscriber_list(client, port, &port->c_src, SRC_LIST); - clear_subscriber_list(client, port, &port->c_dest, DEST_LIST); + clear_subscriber_list(client, port, &port->c_src, true); + clear_subscriber_list(client, port, &port->c_dest, false); if (port->private_free) port->private_free(port->private_data); @@ -479,6 +480,75 @@ static int match_subs_info(struct snd_seq_port_subscribe *r, return 0; } +static int check_and_subscribe_port(struct snd_seq_client *client, + struct snd_seq_client_port *port, + struct snd_seq_subscribers *subs, + bool is_src, bool exclusive, bool ack) +{ + struct snd_seq_port_subs_info *grp; + struct list_head *p; + struct snd_seq_subscribers *s; + int err; + + grp = is_src ? &port->c_src : &port->c_dest; + err = -EBUSY; + down_write(&grp->list_mutex); + if (exclusive) { + if (!list_empty(&grp->list_head)) + goto __error; + } else { + if (grp->exclusive) + goto __error; + /* check whether already exists */ + list_for_each(p, &grp->list_head) { + s = get_subscriber(p, is_src); + if (match_subs_info(&subs->info, &s->info)) + goto __error; + } + } + + err = subscribe_port(client, port, grp, &subs->info, ack); + if (err < 0) { + grp->exclusive = 0; + goto __error; + } + + /* add to list */ + write_lock_irq(&grp->list_lock); + if (is_src) + list_add_tail(&subs->src_list, &grp->list_head); + else + list_add_tail(&subs->dest_list, &grp->list_head); + grp->exclusive = exclusive; + atomic_inc(&subs->ref_count); + write_unlock_irq(&grp->list_lock); + err = 0; + + __error: + up_write(&grp->list_mutex); + return err; +} + +static void delete_and_unsubscribe_port(struct snd_seq_client *client, + struct snd_seq_client_port *port, + struct snd_seq_subscribers *subs, + bool is_src, bool ack) +{ + struct snd_seq_port_subs_info *grp; + + grp = is_src ? &port->c_src : &port->c_dest; + down_write(&grp->list_mutex); + write_lock_irq(&grp->list_lock); + if (is_src) + list_del(&subs->src_list); + else + list_del(&subs->dest_list); + grp->exclusive = 0; + write_unlock_irq(&grp->list_lock); + up_write(&grp->list_mutex); + + unsubscribe_port(client, port, grp, &subs->info, ack); +} /* connect two ports */ int snd_seq_port_connect(struct snd_seq_client *connector, @@ -488,76 +558,42 @@ int snd_seq_port_connect(struct snd_seq_client *connector, struct snd_seq_client_port *dest_port, struct snd_seq_port_subscribe *info) { - struct snd_seq_port_subs_info *src = &src_port->c_src; - struct snd_seq_port_subs_info *dest = &dest_port->c_dest; - struct snd_seq_subscribers *subs, *s; - int err, src_called = 0; - unsigned long flags; - int exclusive; + struct snd_seq_subscribers *subs; + bool exclusive; + int err; subs = kzalloc(sizeof(*subs), GFP_KERNEL); - if (! subs) + if (!subs) return -ENOMEM; subs->info = *info; - atomic_set(&subs->ref_count, 2); + atomic_set(&subs->ref_count, 0); + INIT_LIST_HEAD(&subs->src_list); + INIT_LIST_HEAD(&subs->dest_list); - down_write(&src->list_mutex); - down_write_nested(&dest->list_mutex, SINGLE_DEPTH_NESTING); + exclusive = !!(info->flags & SNDRV_SEQ_PORT_SUBS_EXCLUSIVE); - exclusive = info->flags & SNDRV_SEQ_PORT_SUBS_EXCLUSIVE ? 1 : 0; - err = -EBUSY; - if (exclusive) { - if (! list_empty(&src->list_head) || ! list_empty(&dest->list_head)) - goto __error; - } else { - if (src->exclusive || dest->exclusive) - goto __error; - /* check whether already exists */ - list_for_each_entry(s, &src->list_head, src_list) { - if (match_subs_info(info, &s->info)) - goto __error; - } - list_for_each_entry(s, &dest->list_head, dest_list) { - if (match_subs_info(info, &s->info)) - goto __error; - } - } + err = check_and_subscribe_port(src_client, src_port, subs, true, + exclusive, + connector->number != src_client->number); + if (err < 0) + goto error; + err = check_and_subscribe_port(dest_client, dest_port, subs, false, + exclusive, + connector->number != dest_client->number); + if (err < 0) + goto error_dest; - if ((err = subscribe_port(src_client, src_port, src, info, - connector->number != src_client->number)) < 0) - goto __error; - src_called = 1; - - if ((err = subscribe_port(dest_client, dest_port, dest, info, - connector->number != dest_client->number)) < 0) - goto __error; - - /* add to list */ - write_lock_irqsave(&src->list_lock, flags); - // write_lock(&dest->list_lock); // no other lock yet - list_add_tail(&subs->src_list, &src->list_head); - list_add_tail(&subs->dest_list, &dest->list_head); - // write_unlock(&dest->list_lock); // no other lock yet - write_unlock_irqrestore(&src->list_lock, flags); - - src->exclusive = dest->exclusive = exclusive; - - up_write(&dest->list_mutex); - up_write(&src->list_mutex); return 0; - __error: - if (src_called) - unsubscribe_port(src_client, src_port, src, info, - connector->number != src_client->number); + error_dest: + delete_and_unsubscribe_port(src_client, src_port, subs, true, + connector->number != src_client->number); + error: kfree(subs); - up_write(&dest->list_mutex); - up_write(&src->list_mutex); return err; } - /* remove the connection */ int snd_seq_port_disconnect(struct snd_seq_client *connector, struct snd_seq_client *src_client, @@ -567,37 +603,28 @@ int snd_seq_port_disconnect(struct snd_seq_client *connector, struct snd_seq_port_subscribe *info) { struct snd_seq_port_subs_info *src = &src_port->c_src; - struct snd_seq_port_subs_info *dest = &dest_port->c_dest; struct snd_seq_subscribers *subs; int err = -ENOENT; - unsigned long flags; down_write(&src->list_mutex); - down_write_nested(&dest->list_mutex, SINGLE_DEPTH_NESTING); - /* look for the connection */ list_for_each_entry(subs, &src->list_head, src_list) { if (match_subs_info(info, &subs->info)) { - write_lock_irqsave(&src->list_lock, flags); - // write_lock(&dest->list_lock); // no lock yet - list_del(&subs->src_list); - list_del(&subs->dest_list); - // write_unlock(&dest->list_lock); - write_unlock_irqrestore(&src->list_lock, flags); - src->exclusive = dest->exclusive = 0; - unsubscribe_port(src_client, src_port, src, info, - connector->number != src_client->number); - unsubscribe_port(dest_client, dest_port, dest, info, - connector->number != dest_client->number); - kfree(subs); + atomic_dec(&subs->ref_count); /* mark as not ready */ err = 0; break; } } - - up_write(&dest->list_mutex); up_write(&src->list_mutex); - return err; + if (err < 0) + return err; + + delete_and_unsubscribe_port(src_client, src_port, subs, true, + connector->number != src_client->number); + delete_and_unsubscribe_port(dest_client, dest_port, subs, false, + connector->number != dest_client->number); + kfree(subs); + return 0; }