path: root/drivers/scsi/be2iscsi/be_iscsi.c

/**
 * Copyright (C) 2005 - 2011 Emulex
 * All rights reserved.
 *
 * 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.  The full GNU General
 * Public License is included in this distribution in the file called COPYING.
 *
 * Written by: Jayamohan Kallickal (jayamohan.kallickal@emulex.com)
 *
 * Contact Information:
 * linux-drivers@emulex.com
 *
 * Emulex
 * 3333 Susan Street
 * Costa Mesa, CA 92626
 */

#include <scsi/libiscsi.h>
#include <scsi/scsi_transport_iscsi.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_netlink.h>
#include <net/netlink.h>
#include <scsi/scsi.h>

#include "be_iscsi.h"

extern struct iscsi_transport beiscsi_iscsi_transport;

/**
 * beiscsi_session_create - creates a new iscsi session
 * @cmds_max: max commands supported
 * @qdepth: max queue depth supported
 * @initial_cmdsn: initial iscsi CMDSN
 */
struct iscsi_cls_session *beiscsi_session_create(struct iscsi_endpoint *ep,
						 u16 cmds_max,
						 u16 qdepth,
						 u32 initial_cmdsn)
{
	struct Scsi_Host *shost;
	struct beiscsi_endpoint *beiscsi_ep;
	struct iscsi_cls_session *cls_session;
	struct beiscsi_hba *phba;
	struct iscsi_session *sess;
	struct beiscsi_session *beiscsi_sess;
	struct beiscsi_io_task *io_task;

	SE_DEBUG(DBG_LVL_8, "In beiscsi_session_create\n");

	if (!ep) {
		SE_DEBUG(DBG_LVL_1, "beiscsi_session_create: invalid ep\n");
		return NULL;
	}
	beiscsi_ep = ep->dd_data;
	phba = beiscsi_ep->phba;
	shost = phba->shost;
	if (cmds_max > beiscsi_ep->phba->params.wrbs_per_cxn) {
		shost_printk(KERN_ERR, shost, "Cannot handle %d cmds."
			     "Max cmds per session supported is %d. Using %d. "
			     "\n", cmds_max,
			      beiscsi_ep->phba->params.wrbs_per_cxn,
			      beiscsi_ep->phba->params.wrbs_per_cxn);
		cmds_max = beiscsi_ep->phba->params.wrbs_per_cxn;
	}

	cls_session = iscsi_session_setup(&beiscsi_iscsi_transport,
					  shost, cmds_max,
					  sizeof(*beiscsi_sess),
					  sizeof(*io_task),
					  initial_cmdsn, ISCSI_MAX_TARGET);
	if (!cls_session)
		return NULL;
	sess = cls_session->dd_data;
	beiscsi_sess = sess->dd_data;
	beiscsi_sess->bhs_pool =  pci_pool_create("beiscsi_bhs_pool",
						   phba->pcidev,
						   sizeof(struct be_cmd_bhs),
						   64, 0);
	if (!beiscsi_sess->bhs_pool)
		goto destroy_sess;

	return cls_session;
destroy_sess:
	iscsi_session_teardown(cls_session);
	return NULL;
}

/**
 * beiscsi_session_destroy - destroys iscsi session
 * @cls_session:	pointer to iscsi cls session
 *
 * Destroys iSCSI session instance and releases
 * resources allocated for it.
 */
void beiscsi_session_destroy(struct iscsi_cls_session *cls_session)
{
	struct iscsi_session *sess = cls_session->dd_data;
	struct beiscsi_session *beiscsi_sess = sess->dd_data;

	SE_DEBUG(DBG_LVL_8, "In beiscsi_session_destroy\n");
	pci_pool_destroy(beiscsi_sess->bhs_pool);
	iscsi_session_teardown(cls_session);
}

/**
 * beiscsi_conn_create - create an instance of iscsi connection
 * @cls_session: ptr to iscsi_cls_session
 * @cid: iscsi cid
 */
struct iscsi_cls_conn *
beiscsi_conn_create(struct iscsi_cls_session *cls_session, u32 cid)
{
	struct beiscsi_hba *phba;
	struct Scsi_Host *shost;
	struct iscsi_cls_conn *cls_conn;
	struct beiscsi_conn *beiscsi_conn;
	struct iscsi_conn *conn;
	struct iscsi_session *sess;
	struct beiscsi_session *beiscsi_sess;

	SE_DEBUG(DBG_LVL_8, "In beiscsi_conn_create ,cid"
		 "from iscsi layer=%d\n", cid);
	shost = iscsi_session_to_shost(cls_session);
	phba = iscsi_host_priv(shost);

	cls_conn = iscsi_conn_setup(cls_session, sizeof(*beiscsi_conn), cid);
	if (!cls_conn)
		return NULL;

	conn = cls_conn->dd_data;
	beiscsi_conn = conn->dd_data;
	beiscsi_conn->ep = NULL;
	beiscsi_conn->phba = phba;
	beiscsi_conn->conn = conn;
	sess = cls_session->dd_data;
	beiscsi_sess = sess->dd_data;
	beiscsi_conn->beiscsi_sess = beiscsi_sess;
	return cls_conn;
}

/**
 * beiscsi_bindconn_cid - Bind the beiscsi_conn with phba connection table
 * @beiscsi_conn: The pointer to  beiscsi_conn structure
 * @phba: The phba instance
 * @cid: The cid to free
 */
static int beiscsi_bindconn_cid(struct beiscsi_hba *phba,
				struct beiscsi_conn *beiscsi_conn,
				unsigned int cid)
{
	if (phba->conn_table[cid]) {
		SE_DEBUG(DBG_LVL_1,
			 "Connection table already occupied. Detected clash\n");
		return -EINVAL;
	} else {
		SE_DEBUG(DBG_LVL_8, "phba->conn_table[%d]=%p(beiscsi_conn)\n",
			 cid, beiscsi_conn);
		phba->conn_table[cid] = beiscsi_conn;
	}
	return 0;
}

/**
 * beiscsi_conn_bind - Binds iscsi session/connection with TCP connection
 * @cls_session: pointer to iscsi cls session
 * @cls_conn: pointer to iscsi cls conn
 * @transport_fd: EP handle(64 bit)
 *
 * This function binds the TCP Conn with iSCSI Connection and Session.
 */
int beiscsi_conn_bind(struct iscsi_cls_session *cls_session,
		      struct iscsi_cls_conn *cls_conn,
		      u64 transport_fd, int is_leading)
{
	struct iscsi_conn *conn = cls_conn->dd_data;
	struct beiscsi_conn *beiscsi_conn = conn->dd_data;
	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
	struct beiscsi_hba *phba = iscsi_host_priv(shost);
	struct beiscsi_endpoint *beiscsi_ep;
	struct iscsi_endpoint *ep;

	SE_DEBUG(DBG_LVL_8, "In beiscsi_conn_bind\n");
	ep = iscsi_lookup_endpoint(transport_fd);
	if (!ep)
		return -EINVAL;

	beiscsi_ep = ep->dd_data;

	if (iscsi_conn_bind(cls_session, cls_conn, is_leading))
		return -EINVAL;

	if (beiscsi_ep->phba != phba) {
		SE_DEBUG(DBG_LVL_8,
			 "beiscsi_ep->hba=%p not equal to phba=%p\n