Esempi in C++ (Cpp) per xpc_allocate_msg_slot_uv

Esempio n. 1

File: xpc_uv.c Progetto: 020gzh/linux

static enum xp_retval
xpc_send_payload_uv(struct xpc_channel *ch, u32 flags, void *payload,
		    u16 payload_size, u8 notify_type, xpc_notify_func func,
		    void *key)
{
	enum xp_retval ret = xpSuccess;
	struct xpc_send_msg_slot_uv *msg_slot = NULL;
	struct xpc_notify_mq_msg_uv *msg;
	u8 msg_buffer[XPC_NOTIFY_MSG_SIZE_UV];
	size_t msg_size;

	DBUG_ON(notify_type != XPC_N_CALL);

	msg_size = sizeof(struct xpc_notify_mq_msghdr_uv) + payload_size;
	if (msg_size > ch->entry_size)
		return xpPayloadTooBig;

	xpc_msgqueue_ref(ch);

	if (ch->flags & XPC_C_DISCONNECTING) {
		ret = ch->reason;
		goto out_1;
	}
	if (!(ch->flags & XPC_C_CONNECTED)) {
		ret = xpNotConnected;
		goto out_1;
	}

	ret = xpc_allocate_msg_slot_uv(ch, flags, &msg_slot);
	if (ret != xpSuccess)
		goto out_1;

	if (func != NULL) {
		atomic_inc(&ch->n_to_notify);

		msg_slot->key = key;
		smp_wmb(); /* a non-NULL func must hit memory after the key */
		msg_slot->func = func;

		if (ch->flags & XPC_C_DISCONNECTING) {
			ret = ch->reason;
			goto out_2;
		}
	}

	msg = (struct xpc_notify_mq_msg_uv *)&msg_buffer;
	msg->hdr.partid = xp_partition_id;
	msg->hdr.ch_number = ch->number;
	msg->hdr.size = msg_size;
	msg->hdr.msg_slot_number = msg_slot->msg_slot_number;
	memcpy(&msg->payload, payload, payload_size);

	ret = xpc_send_gru_msg(ch->sn.uv.cached_notify_gru_mq_desc, msg,
			       msg_size);
	if (ret == xpSuccess)
		goto out_1;

	XPC_DEACTIVATE_PARTITION(&xpc_partitions[ch->partid], ret);
out_2:
	if (func != NULL) {
		/*
		 * Try to NULL the msg_slot's func field. If we fail, then
		 * xpc_notify_senders_of_disconnect_uv() beat us to it, in which
		 * case we need to pretend we succeeded to send the message
		 * since the user will get a callout for the disconnect error
		 * by xpc_notify_senders_of_disconnect_uv(), and to also get an
		 * error returned here will confuse them. Additionally, since
		 * in this case the channel is being disconnected we don't need
		 * to put the the msg_slot back on the free list.
		 */
		if (cmpxchg(&msg_slot->func, func, NULL) != func) {
			ret = xpSuccess;
			goto out_1;
		}

		msg_slot->key = NULL;
		atomic_dec(&ch->n_to_notify);
	}
	xpc_free_msg_slot_uv(ch, msg_slot);
out_1:
	xpc_msgqueue_deref(ch);
	return ret;
}

Esempio n. 2

static enum xp_retval
xpc_send_payload_uv(struct xpc_channel *ch, u32 flags, void *payload,
		    u16 payload_size, u8 notify_type, xpc_notify_func func,
		    void *key)
{
	enum xp_retval ret = xpSuccess;
	struct xpc_send_msg_slot_uv *msg_slot = NULL;
	struct xpc_notify_mq_msg_uv *msg;
	u8 msg_buffer[XPC_NOTIFY_MSG_SIZE_UV];
	size_t msg_size;

	DBUG_ON(notify_type != XPC_N_CALL);

	msg_size = sizeof(struct xpc_notify_mq_msghdr_uv) + payload_size;
	if (msg_size > ch->entry_size)
		return xpPayloadTooBig;

	xpc_msgqueue_ref(ch);

	if (ch->flags & XPC_C_DISCONNECTING) {
		ret = ch->reason;
		goto out_1;
	}
	if (!(ch->flags & XPC_C_CONNECTED)) {
		ret = xpNotConnected;
		goto out_1;
	}

	ret = xpc_allocate_msg_slot_uv(ch, flags, &msg_slot);
	if (ret != xpSuccess)
		goto out_1;

	if (func != NULL) {
		atomic_inc(&ch->n_to_notify);

		msg_slot->key = key;
		smp_wmb(); 
		msg_slot->func = func;

		if (ch->flags & XPC_C_DISCONNECTING) {
			ret = ch->reason;
			goto out_2;
		}
	}

	msg = (struct xpc_notify_mq_msg_uv *)&msg_buffer;
	msg->hdr.partid = xp_partition_id;
	msg->hdr.ch_number = ch->number;
	msg->hdr.size = msg_size;
	msg->hdr.msg_slot_number = msg_slot->msg_slot_number;
	memcpy(&msg->payload, payload, payload_size);

	ret = xpc_send_gru_msg(ch->sn.uv.cached_notify_gru_mq_desc, msg,
			       msg_size);
	if (ret == xpSuccess)
		goto out_1;

	XPC_DEACTIVATE_PARTITION(&xpc_partitions[ch->partid], ret);
out_2:
	if (func != NULL) {
		
		if (cmpxchg(&msg_slot->func, func, NULL) != func) {
			ret = xpSuccess;
			goto out_1;
		}

		msg_slot->key = NULL;
		atomic_dec(&ch->n_to_notify);
	}
	xpc_free_msg_slot_uv(ch, msg_slot);
out_1:
	xpc_msgqueue_deref(ch);
	return ret;
}