path: root/drivers/target/target_core_device.c

/*******************************************************************************
 * Filename:  target_core_device.c (based on iscsi_target_device.c)
 *
 * This file contains the TCM Virtual Device and Disk Transport
 * agnostic related functions.
 *
 * (c) Copyright 2003-2012 RisingTide Systems LLC.
 *
 * Nicholas A. Bellinger <nab@kernel.org>
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 ******************************************************************************/

#include <linux/net.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/kthread.h>
#include <linux/in.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_device.h>

#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_fabric.h>

#include "target_core_internal.h"
#include "target_core_alua.h"
#include "target_core_pr.h"
#include "target_core_ua.h"

static struct se_hba *lun0_hba;
/* not static, needed by tpg.c */
struct se_device *g_lun0_dev;

sense_reason_t
transport_lookup_cmd_lun(struct se_cmd *se_cmd, u32 unpacked_lun)
{
	struct se_lun *se_lun = NULL;
	struct se_session *se_sess = se_cmd->se_sess;
	struct se_device *dev;
	unsigned long flags;

	if (unpacked_lun >= TRANSPORT_MAX_LUNS_PER_TPG)
		return TCM_NON_EXISTENT_LUN;

	spin_lock_irqsave(&se_sess->se_node_acl->device_list_lock, flags);
	se_cmd->se_deve = se_sess->se_node_acl->device_list[unpacked_lun];
	if (se_cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_INITIATOR_ACCESS) {
		struct se_dev_entry *deve = se_cmd->se_deve;

		deve->total_cmds++;

		if ((se_cmd->data_direction == DMA_TO_DEVICE) &&
		    (deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY)) {
			pr_err("TARGET_CORE[%s]: Detected WRITE_PROTECTED LUN"
				" Access for 0x%08x\n",
				se_cmd->se_tfo->get_fabric_name(),
				unpacked_lun);
			spin_unlock_irqrestore(&se_sess->se_node_acl->device_list_lock, flags);
			return TCM_WRITE_PROTECTED;
		}

		if (se_cmd->data_direction == DMA_TO_DEVICE)
			deve->write_bytes += se_cmd->data_length;
		else if (se_cmd->data_direction == DMA_FROM_DEVICE)
			deve->read_bytes += se_cmd->data_length;

		se_lun = deve->se_lun;
		se_cmd->se_lun = deve->se_lun;
		se_cmd->pr_res_key = deve->pr_res_key;
		se_cmd->orig_fe_lun = unpacked_lun;
		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
	}
	spin_unlock_irqrestore(&se_sess->se_node_acl->device_list_lock, flags);

	if (!se_lun) {
		/*
		 * Use the se_portal_group->tpg_virt_lun0 to allow for
		 * REPORT_LUNS, et al to be returned when no active
		 * MappedLUN=0 exists for this Initiator Port.
		 */
		if (unpacked_lun != 0) {
			pr_err("TARGET_CORE[%s]: Detected NON_EXISTENT_LUN"
				" Access for 0x%08x\n",
				se_cmd->se_tfo->get_fabric_name(),
				unpacked_lun);
			return TCM_NON_EXISTENT_LUN;
		}
		/*
		 * Force WRITE PROTECT for virtual LUN 0
		 */
		if ((se_cmd->data_direction != DMA_FROM_DEVICE) &&
		    (se_cmd->data_direction != DMA_NONE))
			return TCM_WRITE_PROTECTED;

		se_lun = &se_sess->se_tpg->tpg_virt_lun0;
		se_cmd->se_lun = &se_sess->se_tpg->tpg_virt_lun0;
		se_cmd->orig_fe_lun = 0;
		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
	}

	/* Directly associate cmd with se_dev */
	se_cmd->se_dev = se_lun->lun_se_dev;

	/* TODO: get rid of this and use atomics for stats */
	dev = se_lun->lun_se_dev;
	spin_lock_irqsave(&dev->stats_lock, flags);
	dev->num_cmds++;
	if (se_cmd->data_direction == DMA_TO_DEVICE)
		dev->write_bytes += se_cmd->data_length;
	else if (se_cmd->data_direction == DMA_FROM_DEVICE)
		dev->read_bytes += se_cmd->data_length;
	spin_unlock_irqrestore(&dev->stats_lock, flags);

	spin_lock_irqsave(&se_lun->lun_cmd_lock, flags);
	list_add_tail(&se_cmd->se_lun_node, &se_lun->lun_cmd_list);
	spin_unlock_irqrestore(&se_lun->lun_cmd_lock, flags);

	return 0;
}
EXPORT_SYMBOL(transport_lookup_cmd_lun);

int transport_lookup_tmr_lun(struct se_cmd *se_cmd, u32 unpacked_lun)
{
	struct se_dev_entry *deve;
	struct se_lun *se_lun = NULL;
	struct se_session *se_sess = se_cmd->se_sess;
	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
	unsigned long flags;

	if (unpacked_lun >= TRANSPORT_MAX_LUNS_PER_TPG)
		return -ENODEV;

	spin_lock_irqsave(&se_sess->se_node_acl->device