Merge "soc: qcom: qmi: Fix race during service event notification" (1095c86e) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/soc/qcom/qmi_interface.c

+142 −53

Original line number	Diff line number	Diff line
		@@ -1756,14 +1756,54 @@ int qmi_connect_to_service(struct qmi_handle *handle,
		}
		EXPORT_SYMBOL(qmi_connect_to_service);

		/**
		* svc_event_add_svc_addr() - Add a specific service address to the list
		* @event_nb: Reference to the service event structure.
		* @node_id: Node id of the service address.
		* @port_id: Port id of the service address.
		*
		* Return: 0 on success, standard error code otheriwse.
		*
		* This function should be called with svc_addr_list_lock locked.
		*/
		static int svc_event_add_svc_addr(struct svc_event_nb *event_nb,
		uint32_t node_id, uint32_t port_id)
		{

		struct svc_addr *addr;

		if (!event_nb)
		return -EINVAL;
		addr = kmalloc(sizeof(*addr), GFP_KERNEL);
		if (!addr) {
		pr_err("%s: Memory allocation failed for address list\n",
		__func__);
		return -ENOMEM;
		}
		addr->port_addr.node_id = node_id;
		addr->port_addr.port_id = port_id;
		list_add_tail(&addr->list_node, &event_nb->svc_addr_list);
		return 0;
		}

		/**
		* qmi_notify_svc_event_arrive() - Notify the clients about service arrival
		* @service: Service id for the specific service.
		* @instance: Instance id for the specific service.
		* @node_id: Node id of the processor where the service is hosted.
		* @port_id: Port id of the service port created by IPC Router.
		*
		* Return: 0 on Success or standard error code.
		*/
		static int qmi_notify_svc_event_arrive(uint32_t service,
		uint32_t instance)
		uint32_t instance,
		uint32_t node_id,
		uint32_t port_id)
		{
		struct svc_event_nb *temp;
		unsigned long flags;
		struct msm_ipc_port_name svc_name;
		struct msm_ipc_server_info svc_info;
		int ret;
		struct svc_addr *addr;
		bool already_notified = false;

		mutex_lock(&svc_event_nb_list_lock);
		temp = find_svc_event_nb(service, instance);
		@@ -1771,33 +1811,47 @@ static int qmi_notify_svc_event_arrive(uint32_t service,
		mutex_unlock(&svc_event_nb_list_lock);
		return -EINVAL;
		}
		svc_name.service = service;
		svc_name.instance = instance;
		ret = msm_ipc_router_lookup_server_name(&svc_name, &svc_info,
		1, LOOKUP_MASK);
		spin_lock_irqsave(&temp->nb_lock, flags);
		if (temp->svc_avail < ret) {
		mutex_unlock(&svc_event_nb_list_lock);

		mutex_lock(&temp->svc_addr_list_lock);
		list_for_each_entry(addr, &temp->svc_addr_list, list_node)
		if (addr->port_addr.node_id == node_id &&
		addr->port_addr.port_id == port_id)
		already_notified = true;
		if (!already_notified) {
		/*
		* Notify only if the clients are not notified about the
		* service during registration.
		*/
		temp->svc_avail = ret;
		svc_event_add_svc_addr(temp, node_id, port_id);
		spin_lock_irqsave(&temp->nb_lock, flags);
		raw_notifier_call_chain(&temp->svc_event_rcvr_list,
		QMI_SERVER_ARRIVE, NULL);
		}
		spin_unlock_irqrestore(&temp->nb_lock, flags);
		mutex_unlock(&svc_event_nb_list_lock);
		}
		mutex_unlock(&temp->svc_addr_list_lock);

		return 0;
		}

		/**
		* qmi_notify_svc_event_exit() - Notify the clients about service exit
		* @service: Service id for the specific service.
		* @instance: Instance id for the specific service.
		* @node_id: Node id of the processor where the service is hosted.
		* @port_id: Port id of the service port created by IPC Router.
		*
		* Return: 0 on Success or standard error code.
		*/
		static int qmi_notify_svc_event_exit(uint32_t service,
		uint32_t instance)
		uint32_t instance,
		uint32_t node_id,
		uint32_t port_id)
		{
		struct svc_event_nb *temp;
		unsigned long flags;
		struct msm_ipc_port_name svc_name;
		struct msm_ipc_server_info svc_info;
		int ret;
		struct svc_addr *addr;
		struct svc_addr *temp_addr;

		mutex_lock(&svc_event_nb_list_lock);
		temp = find_svc_event_nb(service, instance);
		@@ -1805,20 +1859,28 @@ static int qmi_notify_svc_event_exit(uint32_t service,
		mutex_unlock(&svc_event_nb_list_lock);
		return -EINVAL;
		}
		mutex_unlock(&svc_event_nb_list_lock);

		svc_name.service = service;
		svc_name.instance = instance;
		ret = msm_ipc_router_lookup_server_name(&svc_name, &svc_info,
		1, LOOKUP_MASK);
		mutex_lock(&temp->svc_addr_list_lock);
		list_for_each_entry_safe(addr, temp_addr, &temp->svc_addr_list,
		list_node) {
		if (addr->port_addr.node_id == node_id &&
		addr->port_addr.port_id == port_id) {
		/*
		* Notify only if an already notified service has
		* gone down.
		*/
		spin_lock_irqsave(&temp->nb_lock, flags);
		if (temp->svc_avail > ret) {
		/* Notify only if an already notified service has gone down */
		temp->svc_avail = ret;
		raw_notifier_call_chain(&temp->svc_event_rcvr_list,
		QMI_SERVER_EXIT, NULL);
		}
		spin_unlock_irqrestore(&temp->nb_lock, flags);
		mutex_unlock(&svc_event_nb_list_lock);
		list_del(&addr->list_node);
		kfree(addr);
		}
		}

		mutex_unlock(&temp->svc_addr_list_lock);

		return 0;
		}

		@@ -1863,8 +1925,9 @@ static struct svc_event_nb *find_and_add_svc_event_nb(uint32_t service_id,
		temp->service_id = service_id;
		temp->instance_id = instance_id;
		INIT_LIST_HEAD(&temp->list);
		INIT_LIST_HEAD(&temp->svc_addr_list);
		RAW_INIT_NOTIFIER_HEAD(&temp->svc_event_rcvr_list);

		mutex_init(&temp->svc_addr_list_lock);
		list_add_tail(&temp->list, &svc_event_nb_list);

		return temp;
		@@ -1877,10 +1940,12 @@ int qmi_svc_event_notifier_register(uint32_t service_id,
		{
		struct svc_event_nb *temp;
		unsigned long flags;
		int ret, num_servers;
		int ret;
		int i;
		int num_servers;
		uint32_t instance_id;
		struct msm_ipc_port_name svc_name;
		struct msm_ipc_server_info svc_info;
		struct msm_ipc_server_info *svc_info_arr = NULL;

		mutex_lock(&qmi_svc_event_notifier_lock);
		if (!qmi_svc_event_notifier_port && !qmi_svc_event_notifier_wq)
		@@ -1894,31 +1959,51 @@ int qmi_svc_event_notifier_register(uint32_t service_id,
		mutex_unlock(&svc_event_nb_list_lock);
		return -EFAULT;
		}
		svc_name.service = service_id;
		svc_name.instance = instance_id;
		num_servers = msm_ipc_router_lookup_server_name(&svc_name, &svc_info,
		1, LOOKUP_MASK);
		mutex_unlock(&svc_event_nb_list_lock);

		mutex_lock(&temp->svc_addr_list_lock);
		spin_lock_irqsave(&temp->nb_lock, flags);
		ret = raw_notifier_chain_register(&temp->svc_event_rcvr_list, nb);
		if (num_servers != 0 && temp->svc_avail >= num_servers) {
		/*
		* Either all of the existing clients have already been notified
		* or some service has just gone down but there are still some
		* services available. Notify the client now.
		*/
		temp->svc_avail = num_servers;
		spin_unlock_irqrestore(&temp->nb_lock, flags);
		if (!list_empty(&temp->svc_addr_list)) {
		/* Notify this client only if Some services already exist. */
		spin_lock_irqsave(&temp->nb_lock, flags);
		nb->notifier_call(nb, QMI_SERVER_ARRIVE, NULL);
		} else if (num_servers != 0 && temp->svc_avail < num_servers) {
		spin_unlock_irqrestore(&temp->nb_lock, flags);
		} else {
		/*
		* A new server just came up. Notify all the clients including
		* the one that has called notifier register.
		* Check if we have missed a new server event that happened
		* earlier.
		*/
		temp->svc_avail = num_servers;
		svc_name.service = service_id;
		svc_name.instance = instance_id;
		num_servers = msm_ipc_router_lookup_server_name(&svc_name,
		NULL,
		0, LOOKUP_MASK);
		if (num_servers > 0) {
		svc_info_arr = kmalloc_array(num_servers,
		sizeof(*svc_info_arr),
		GFP_KERNEL);
		if (!svc_info_arr)
		return -ENOMEM;
		num_servers = msm_ipc_router_lookup_server_name(
		&svc_name,
		svc_info_arr,
		num_servers,
		LOOKUP_MASK);
		for (i = 0; i < num_servers; i++)
		svc_event_add_svc_addr(temp,
		svc_info_arr[i].node_id,
		svc_info_arr[i].port_id);
		kfree(svc_info_arr);

		spin_lock_irqsave(&temp->nb_lock, flags);
		raw_notifier_call_chain(&temp->svc_event_rcvr_list,
		QMI_SERVER_ARRIVE, NULL);
		}
		spin_unlock_irqrestore(&temp->nb_lock, flags);
		mutex_unlock(&svc_event_nb_list_lock);
		}
		}
		mutex_unlock(&temp->svc_addr_list_lock);

		return ret;
		}
		@@ -1975,10 +2060,14 @@ static void qmi_svc_event_worker(struct work_struct *work)
		}
		if (ctl_msg->cmd == IPC_ROUTER_CTRL_CMD_NEW_SERVER)
		qmi_notify_svc_event_arrive(ctl_msg->srv.service,
		ctl_msg->srv.instance);
		ctl_msg->srv.instance,
		ctl_msg->srv.node_id,
		ctl_msg->srv.port_id);
		else if (ctl_msg->cmd == IPC_ROUTER_CTRL_CMD_REMOVE_SERVER)
		qmi_notify_svc_event_exit(ctl_msg->srv.service,
		ctl_msg->srv.instance);
		ctl_msg->srv.instance,
		ctl_msg->srv.node_id,
		ctl_msg->srv.port_id);
		kfree(ctl_msg);
		}
		}

drivers/soc/qcom/qmi_interface_priv.h

+23 −1

Original line number	Diff line number	Diff line
		@@ -55,13 +55,35 @@ struct qmi_txn {
		wait_queue_head_t wait_q;
		};

		/**
		* svc_addr - Data structure to maintain a list of service addresses.
		* @list_node: Service address list node used by "svc_addr_list"
		* @port_addr: Service address in <node_id:port_id>.
		*/
		struct svc_addr {
		struct list_head list_node;
		struct msm_ipc_port_addr port_addr;
		};

		/**
		* svc_event_nb - Service event notification structure.
		* @nb_lock: Spinlock for the notifier block lists.
		* @service_id: Service id for which list of notifier blocks are maintained.
		* @instance_id: Instance id for which list of notifier blocks are maintained.
		* @svc_event_rcvr_list: List of notifier blocks which clients have registered.
		* @list: Used to chain this structure in a global list.
		* @svc_addr_list_lock: Lock to protect @svc_addr_list.
		* @svc_addr_list: List for mantaining all the address for a specific
		* <service_id:instance_id>.
		*/
		struct svc_event_nb {
		spinlock_t nb_lock;
		uint32_t service_id;
		uint32_t instance_id;
		int svc_avail;
		struct raw_notifier_head svc_event_rcvr_list;
		struct list_head list;
		struct mutex svc_addr_list_lock;
		struct list_head svc_addr_list;
		};

		/**