path: root/drivers/scsi/cxgb3i/cxgb3i_iscsi.c

/* cxgb3i_iscsi.c: Chelsio S3xx iSCSI driver.
 *
 * Copyright (c) 2008 Chelsio Communications, Inc.
 * Copyright (c) 2008 Mike Christie
 * Copyright (c) 2008 Red Hat, Inc.  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 as published by
 * the Free Software Foundation.
 *
 * Written by: Karen Xie (kxie@chelsio.com)
 */

#include <linux/inet.h>
#include <linux/slab.h>
#include <linux/crypto.h>
#include <linux/if_vlan.h>
#include <net/dst.h>
#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/iscsi_proto.h>
#include <scsi/libiscsi.h>
#include <scsi/scsi_transport_iscsi.h>

#include "cxgb3i.h"
#include "cxgb3i_pdu.h"

#ifdef __DEBUG_CXGB3I_TAG__
#define cxgb3i_tag_debug	cxgb3i_log_debug
#else
#define cxgb3i_tag_debug(fmt...)
#endif

#ifdef __DEBUG_CXGB3I_API__
#define cxgb3i_api_debug	cxgb3i_log_debug
#else
#define cxgb3i_api_debug(fmt...)
#endif

/*
 * align pdu size to multiple of 512 for better performance
 */
#define align_pdu_size(n) do { n = (n) & (~511); } while (0)

static struct scsi_transport_template *cxgb3i_scsi_transport;
static struct scsi_host_template cxgb3i_host_template;
static struct iscsi_transport cxgb3i_iscsi_transport;
static unsigned char sw_tag_idx_bits;
static unsigned char sw_tag_age_bits;

static LIST_HEAD(cxgb3i_snic_list);
static DEFINE_RWLOCK(cxgb3i_snic_rwlock);

/**
 * cxgb3i_adpater_find_by_tdev - find the cxgb3i_adapter structure via t3cdev
 * @tdev: t3cdev pointer
 */
struct cxgb3i_adapter *cxgb3i_adapter_find_by_tdev(struct t3cdev *tdev)
{
	struct cxgb3i_adapter *snic;

	read_lock(&cxgb3i_snic_rwlock);
	list_for_each_entry(snic, &cxgb3i_snic_list, list_head) {
		if (snic->tdev == tdev) {
			read_unlock(&cxgb3i_snic_rwlock);
			return snic;
		}
	}
	read_unlock(&cxgb3i_snic_rwlock);
	return NULL;
}

static inline int adapter_update(struct cxgb3i_adapter *snic)
{
	cxgb3i_log_info("snic 0x%p, t3dev 0x%p, updating.\n",
			snic, snic->tdev);
	return cxgb3i_adapter_ddp_info(snic->tdev, &snic->tag_format,
					&snic->tx_max_size,
					&snic->rx_max_size);
}

static int adapter_add(struct cxgb3i_adapter *snic)
{
	struct t3cdev *t3dev = snic->tdev;
	struct adapter *adapter = tdev2adap(t3dev);
	int i, err;

	snic->pdev = adapter->pdev;
	snic->tag_format.sw_bits = sw_tag_idx_bits + sw_tag_age_bits;

	err = cxgb3i_adapter_ddp_info(t3dev, &snic->tag_format,
				    &snic->tx_max_size,
				    &snic->rx_max_size);
	if (err < 0)
		return err;

	for_each_port(adapter, i) {
		snic->hba[i] = cxgb3i_hba_host_add(snic, adapter->port[i]);
		if (!snic->hba[i])
			return -EINVAL;
	}
	snic->hba_cnt = adapter->params.nports;

	/* add to the list */
	write_lock(&cxgb3i_snic_rwlock);
	list_add_tail(&snic->list_head, &cxgb3i_snic_list);
	write_unlock(&cxgb3i_snic_rwlock);

	cxgb3i_log_info("t3dev 0x%p open, snic 0x%p, %u scsi hosts added.\n",
			t3dev, snic, snic->hba_cnt);
	return 0;
}

/**
 * cxgb3i_adapter_open - init a s3 adapter structure and any h/w settings
 * @t3dev: t3cdev adapter
 */
void cxgb3i_adapter_open(struct t3cdev *t3dev)
{
	struct cxgb3i_adapter *snic = cxgb3i_adapter_find_by_tdev(t3dev);
	int err;

	if (snic)
		err = adapter_update(snic);
	else {
		snic = kzalloc(sizeof(*snic), GFP_KERNEL);
		if (snic) {
			spin_lock_init(&snic->lock);
			snic->tdev = t3dev;
			err = adapter_add(snic);
		} else
			err = -ENOMEM;
	}

	if (err < 0) {
		cxgb3i_log_info("snic 0x%p, f 0x%x, t3dev 0x%p open, err %d.\n",
				snic, snic ? snic->flags : 0, t3dev, err);
		if (snic) {
			snic->flags &= ~CXGB3I_ADAPTER_FLAG_RESET;
			cxgb3i_adapter_close(t3dev);
		}
	}
}

/**
 * cxgb3i_adapter_close - release the resources held and cleanup h/w settings
 * @t3dev: t3cdev adapter
 */
void cxgb3i_adapter_close(struct t3cdev *t3dev)
{
	struct cxgb3i_adapter *snic = cxgb3i_adapter_find_by_tdev(t3dev);
	int i;

	if (!snic || snic->flags & CXGB3I_ADAPTER_FLAG_RESET) {
		cxgb3i_log_info("t3dev 0x%p close, snic 0x%p, f 0x%x.\n",
				t3dev, snic, snic ? snic->flags : 0);
		</