iscsi_iser.c

linux内核源码

	 * verified against the global ib connections list */
	ib_conn = iscsi_iser_ib_conn_lookup(transport_eph);
	if (!ib_conn) {
		iser_err("can't bind eph %llx\n",
			 (unsigned long long)transport_eph);
		return -EINVAL;
	}
	/* binds the iSER connection retrieved from the previously
	 * connected ep_handle to the iSCSI layer connection. exchanges
	 * connection pointers */
	iser_err("binding iscsi conn %p to iser_conn %p\n",conn,ib_conn);
	iser_conn = conn->dd_data;
	ib_conn->iser_conn = iser_conn;
	iser_conn->ib_conn  = ib_conn;

	conn->recv_lock = &iser_conn->lock;

	return 0;
}

static int
iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
{
	struct iscsi_conn *conn = cls_conn->dd_data;
	int err;

	err = iser_conn_set_full_featured_mode(conn);
	if (err)
		return err;

	return iscsi_conn_start(cls_conn);
}

static struct iscsi_transport iscsi_iser_transport;

static struct iscsi_cls_session *
iscsi_iser_session_create(struct iscsi_transport *iscsit,
			 struct scsi_transport_template *scsit,
			 uint16_t cmds_max, uint16_t qdepth,
			 uint32_t initial_cmdsn, uint32_t *hostno)
{
	struct iscsi_cls_session *cls_session;
	struct iscsi_session *session;
	int i;
	uint32_t hn;
	struct iscsi_cmd_task  *ctask;
	struct iscsi_mgmt_task *mtask;
	struct iscsi_iser_cmd_task *iser_ctask;
	struct iser_desc *desc;

	/*
	 * we do not support setting can_queue cmd_per_lun from userspace yet
	 * because we preallocate so many resources
	 */
	cls_session = iscsi_session_setup(iscsit, scsit,
					  ISCSI_DEF_XMIT_CMDS_MAX,
					  ISCSI_MAX_CMD_PER_LUN,
					  sizeof(struct iscsi_iser_cmd_task),
					  sizeof(struct iser_desc),
					  initial_cmdsn, &hn);
	if (!cls_session)
	return NULL;

	*hostno = hn;
	session = class_to_transport_session(cls_session);

	/* libiscsi setup itts, data and pool so just set desc fields */
	for (i = 0; i < session->cmds_max; i++) {
		ctask      = session->cmds[i];
		iser_ctask = ctask->dd_data;
		ctask->hdr = (struct iscsi_cmd *)&iser_ctask->desc.iscsi_header;
	}

	for (i = 0; i < session->mgmtpool_max; i++) {
		mtask      = session->mgmt_cmds[i];
		desc       = mtask->dd_data;
		mtask->hdr = &desc->iscsi_header;
		desc->data = mtask->data;
	}

	return cls_session;
}

static int
iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
		     enum iscsi_param param, char *buf, int buflen)
{
	int value;

	switch (param) {
	case ISCSI_PARAM_MAX_RECV_DLENGTH:
		/* TBD */
		break;
	case ISCSI_PARAM_HDRDGST_EN:
		sscanf(buf, "%d", &value);
		if (value) {
			printk(KERN_ERR "DataDigest wasn't negotiated to None");
			return -EPROTO;
		}
		break;
	case ISCSI_PARAM_DATADGST_EN:
		sscanf(buf, "%d", &value);
		if (value) {
			printk(KERN_ERR "DataDigest wasn't negotiated to None");
			return -EPROTO;
		}
		break;
	case ISCSI_PARAM_IFMARKER_EN:
		sscanf(buf, "%d", &value);
		if (value) {
			printk(KERN_ERR "IFMarker wasn't negotiated to No");
			return -EPROTO;
		}
		break;
	case ISCSI_PARAM_OFMARKER_EN:
		sscanf(buf, "%d", &value);
		if (value) {
			printk(KERN_ERR "OFMarker wasn't negotiated to No");
			return -EPROTO;
		}
		break;
	default:
		return iscsi_set_param(cls_conn, param, buf, buflen);
	}

	return 0;
}

static void
iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
{
	struct iscsi_conn *conn = cls_conn->dd_data;

	stats->txdata_octets = conn->txdata_octets;
	stats->rxdata_octets = conn->rxdata_octets;
	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
	stats->dataout_pdus = conn->dataout_pdus_cnt;
	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
	stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
	stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
	stats->custom_length = 3;
	strcpy(stats->custom[0].desc, "qp_tx_queue_full");
	stats->custom[0].value = 0; /* TB iser_conn->qp_tx_queue_full; */
	strcpy(stats->custom[1].desc, "fmr_map_not_avail");
	stats->custom[1].value = 0; /* TB iser_conn->fmr_map_not_avail */;
	strcpy(stats->custom[2].desc, "eh_abort_cnt");
	stats->custom[2].value = conn->eh_abort_cnt;
}

static int
iscsi_iser_ep_connect(struct sockaddr *dst_addr, int non_blocking,
		      __u64 *ep_handle)
{
	int err;
	struct iser_conn *ib_conn;

	err = iser_conn_init(&ib_conn);
	if (err)
		goto out;

	err = iser_connect(ib_conn, NULL, (struct sockaddr_in *)dst_addr, non_blocking);
	if (!err)
		*ep_handle = (__u64)(unsigned long)ib_conn;

out:
	return err;
}

static int
iscsi_iser_ep_poll(__u64 ep_handle, int timeout_ms)
{
	struct iser_conn *ib_conn = iscsi_iser_ib_conn_lookup(ep_handle);
	int rc;

	if (!ib_conn)
		return -EINVAL;

	rc = wait_event_interruptible_timeout(ib_conn->wait,
			     ib_conn->state == ISER_CONN_UP,
			     msecs_to_jiffies(timeout_ms));

	/* if conn establishment failed, return error code to iscsi */
	if (!rc &&
	    (ib_conn->state == ISER_CONN_TERMINATING ||
	     ib_conn->state == ISER_CONN_DOWN))
		rc = -1;

	iser_err("ib conn %p rc = %d\n", ib_conn, rc);

	if (rc > 0)
		return 1; /* success, this is the equivalent of POLLOUT */
	else if (!rc)
		return 0; /* timeout */
	else
		return rc; /* signal */
}

static void
iscsi_iser_ep_disconnect(__u64 ep_handle)
{
	struct iser_conn *ib_conn;

	ib_conn = iscsi_iser_ib_conn_lookup(ep_handle);
	if (!ib_conn)
		return;

	iser_err("ib conn %p state %d\n",ib_conn, ib_conn->state);
	iser_conn_terminate(ib_conn);
}

static struct scsi_host_template iscsi_iser_sht = {
	.module                 = THIS_MODULE,
	.name                   = "iSCSI Initiator over iSER, v." DRV_VER,
	.queuecommand           = iscsi_queuecommand,
	.can_queue		= ISCSI_DEF_XMIT_CMDS_MAX - 1,
	.sg_tablesize           = ISCSI_ISER_SG_TABLESIZE,
	.max_sectors		= 1024,
	.cmd_per_lun            = ISCSI_MAX_CMD_PER_LUN,
	.eh_abort_handler       = iscsi_eh_abort,
	.eh_host_reset_handler	= iscsi_eh_host_reset,
	.use_clustering         = DISABLE_CLUSTERING,
	.proc_name              = "iscsi_iser",
	.this_id                = -1,
};

static struct iscsi_transport iscsi_iser_transport = {
	.owner                  = THIS_MODULE,
	.name                   = "iser",
	.caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T,
	.param_mask		= ISCSI_MAX_RECV_DLENGTH |
				  ISCSI_MAX_XMIT_DLENGTH |
				  ISCSI_HDRDGST_EN |
				  ISCSI_DATADGST_EN |
				  ISCSI_INITIAL_R2T_EN |
				  ISCSI_MAX_R2T |
				  ISCSI_IMM_DATA_EN |
				  ISCSI_FIRST_BURST |
				  ISCSI_MAX_BURST |
				  ISCSI_PDU_INORDER_EN |
				  ISCSI_DATASEQ_INORDER_EN |
				  ISCSI_EXP_STATSN |
				  ISCSI_PERSISTENT_PORT |
				  ISCSI_PERSISTENT_ADDRESS |
				  ISCSI_TARGET_NAME | ISCSI_TPGT |
				  ISCSI_USERNAME | ISCSI_PASSWORD |
				  ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN,
	.host_param_mask	= ISCSI_HOST_HWADDRESS |
				  ISCSI_HOST_NETDEV_NAME |
				  ISCSI_HOST_INITIATOR_NAME,
	.host_template          = &iscsi_iser_sht,
	.conndata_size		= sizeof(struct iscsi_conn),
	.max_lun                = ISCSI_ISER_MAX_LUN,
	.max_cmd_len            = ISCSI_ISER_MAX_CMD_LEN,
	/* session management */
	.create_session         = iscsi_iser_session_create,
	.destroy_session        = iscsi_session_teardown,
	/* connection management */
	.create_conn            = iscsi_iser_conn_create,
	.bind_conn              = iscsi_iser_conn_bind,
	.destroy_conn           = iscsi_iser_conn_destroy,
	.set_param              = iscsi_iser_set_param,
	.get_conn_param		= iscsi_conn_get_param,
	.get_session_param	= iscsi_session_get_param,
	.start_conn             = iscsi_iser_conn_start,
	.stop_conn              = iscsi_conn_stop,
	/* iscsi host params */
	.get_host_param		= iscsi_host_get_param,
	.set_host_param		= iscsi_host_set_param,
	/* IO */
	.send_pdu		= iscsi_conn_send_pdu,
	.get_stats		= iscsi_iser_conn_get_stats,
	.init_cmd_task		= iscsi_iser_cmd_init,
	.xmit_cmd_task		= iscsi_iser_ctask_xmit,
	.xmit_mgmt_task		= iscsi_iser_mtask_xmit,
	.cleanup_cmd_task	= iscsi_iser_cleanup_ctask,
	/* recovery */
	.session_recovery_timedout = iscsi_session_recovery_timedout,

	.ep_connect             = iscsi_iser_ep_connect,
	.ep_poll                = iscsi_iser_ep_poll,
	.ep_disconnect          = iscsi_iser_ep_disconnect
};

static int __init iser_init(void)
{
	int err;

	iser_dbg("Starting iSER datamover...\n");

	if (iscsi_max_lun < 1) {
		printk(KERN_ERR "Invalid max_lun value of %u\n", iscsi_max_lun);
		return -EINVAL;
	}

	iscsi_iser_transport.max_lun = iscsi_max_lun;

	memset(&ig, 0, sizeof(struct iser_global));

	ig.desc_cache = kmem_cache_create("iser_descriptors",
					  sizeof (struct iser_desc),
					  0, SLAB_HWCACHE_ALIGN,
					  NULL);
	if (ig.desc_cache == NULL)
		return -ENOMEM;

	/* device init is called only after the first addr resolution */
	mutex_init(&ig.device_list_mutex);
	INIT_LIST_HEAD(&ig.device_list);
	mutex_init(&ig.connlist_mutex);
	INIT_LIST_HEAD(&ig.connlist);

	if (!iscsi_register_transport(&iscsi_iser_transport)) {
		iser_err("iscsi_register_transport failed\n");
		err = -EINVAL;
		goto register_transport_failure;
	}

	return 0;

register_transport_failure:
	kmem_cache_destroy(ig.desc_cache);

	return err;
}

static void __exit iser_exit(void)
{
	iser_dbg("Removing iSER datamover...\n");
	iscsi_unregister_transport(&iscsi_iser_transport);
	kmem_cache_destroy(ig.desc_cache);
}

module_init(iser_init);
module_exit(iser_exit);