target_core_base.h

#ifndef TARGET_CORE_BASE_H
#define TARGET_CORE_BASE_H

#include <linux/in.h>
#include <linux/configfs.h>
#include <linux/dma-mapping.h>
#include <linux/blkdev.h>
#include <scsi/scsi_cmnd.h>
#include <net/sock.h>
#include <net/tcp.h>

#define TARGET_CORE_MOD_VERSION		"v4.1.0-rc1-ml"
#define TARGET_CORE_VERSION		TARGET_CORE_MOD_VERSION

/* Maximum Number of LUNs per Target Portal Group */
/* Don't raise above 511 or REPORT_LUNS needs to handle >1 page */
#define TRANSPORT_MAX_LUNS_PER_TPG		256
/*
 * By default we use 32-byte CDBs in TCM Core and subsystem plugin code.
 *
 * Note that both include/scsi/scsi_cmnd.h:MAX_COMMAND_SIZE and
 * include/linux/blkdev.h:BLOCK_MAX_CDB as of v2.6.36-rc4 still use
 * 16-byte CDBs by default and require an extra allocation for
 * 32-byte CDBs to because of legacy issues.
 *
 * Within TCM Core there are no such legacy limitiations, so we go ahead
 * use 32-byte CDBs by default and use include/scsi/scsi.h:scsi_command_size()
 * within all TCM Core and subsystem plugin code.
 */
#define TCM_MAX_COMMAND_SIZE			32
/*
 * From include/scsi/scsi_cmnd.h:SCSI_SENSE_BUFFERSIZE, currently
 * defined 96, but the real limit is 252 (or 260 including the header)
 */
#define TRANSPORT_SENSE_BUFFER			SCSI_SENSE_BUFFERSIZE
/* Used by transport_send_check_condition_and_sense() */
#define SPC_SENSE_KEY_OFFSET			2
#define SPC_ADD_SENSE_LEN_OFFSET		7
#define SPC_ASC_KEY_OFFSET			12
#define SPC_ASCQ_KEY_OFFSET			13
#define TRANSPORT_IQN_LEN			224
/* Used by target_core_store_alua_lu_gp() and target_core_alua_lu_gp_show_attr_members() */
#define LU_GROUP_NAME_BUF			256
/* Used by core_alua_store_tg_pt_gp_info() and target_core_alua_tg_pt_gp_show_attr_members() */
#define TG_PT_GROUP_NAME_BUF			256
/* Used to parse VPD into struct t10_vpd */
#define VPD_TMP_BUF_SIZE			128
/* Used by transport_generic_cmd_sequencer() */
#define READ_BLOCK_LEN          		6
#define READ_CAP_LEN            		8
#define READ_POSITION_LEN       		20
#define INQUIRY_LEN				36
/* Used by transport_get_inquiry_vpd_serial() */
#define INQUIRY_VPD_SERIAL_LEN			254
/* Used by transport_get_inquiry_vpd_device_ident() */
#define INQUIRY_VPD_DEVICE_IDENTIFIER_LEN	254

/* Attempts before moving from SHORT to LONG */
#define PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD	3
#define PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT	3  /* In milliseconds */
#define PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG	10 /* In milliseconds */

#define PYX_TRANSPORT_STATUS_INTERVAL		5 /* In seconds */

/*
 * struct se_subsystem_dev->su_dev_flags
*/
#define SDF_FIRMWARE_VPD_UNIT_SERIAL		0x00000001
#define SDF_EMULATED_VPD_UNIT_SERIAL		0x00000002
#define SDF_USING_UDEV_PATH			0x00000004
#define SDF_USING_ALIAS				0x00000008

/*
 * struct se_device->dev_flags
 */
#define DF_READ_ONLY				0x00000001
#define DF_SPC2_RESERVATIONS			0x00000002
#define DF_SPC2_RESERVATIONS_WITH_ISID		0x00000004

/* struct se_dev_attrib sanity values */
/* Default max_unmap_lba_count */
#define DA_MAX_UNMAP_LBA_COUNT			0
/* Default max_unmap_block_desc_count */
#define DA_MAX_UNMAP_BLOCK_DESC_COUNT		0
/* Default unmap_granularity */
#define DA_UNMAP_GRANULARITY_DEFAULT		0
/* Default unmap_granularity_alignment */
#define DA_UNMAP_GRANULARITY_ALIGNMENT_DEFAULT	0
/* Emulation for Direct Page Out */
#define DA_EMULATE_DPO				0
/* Emulation for Forced Unit Access WRITEs */
#define DA_EMULATE_FUA_WRITE			1
/* Emulation for Forced Unit Access READs */
#define DA_EMULATE_FUA_READ			0
/* Emulation for WriteCache and SYNCHRONIZE_CACHE */
#define DA_EMULATE_WRITE_CACHE			0
/* Emulation for UNIT ATTENTION Interlock Control */
#define DA_EMULATE_UA_INTLLCK_CTRL		0
/* Emulation for TASK_ABORTED status (TAS) by default */
#define DA_EMULATE_TAS				1
/* Emulation for Thin Provisioning UNMAP using block/blk-lib.c:blkdev_issue_discard() */
#define DA_EMULATE_TPU				0
/*
 * Emulation for Thin Provisioning WRITE_SAME w/ UNMAP=1 bit using
 * block/blk-lib.c:blkdev_issue_discard()
 */
#define DA_EMULATE_TPWS				0
/* No Emulation for PSCSI by default */
#define DA_EMULATE_RESERVATIONS			0
/* No Emulation for PSCSI by default */
#define DA_EMULATE_ALUA				0
/* Enforce SCSI Initiator Port TransportID with 'ISID' for PR */
#define DA_ENFORCE_PR_ISIDS			1
#define DA_STATUS_MAX_SECTORS_MIN		16
#define DA_STATUS_MAX_SECTORS_MAX		8192
/* By default don't report non-rotating (solid state) medium */
#define DA_IS_NONROT				0
/* Queue Algorithm Modifier default for restricted reordering in control mode page */
#define DA_EMULATE_REST_REORD			0

#define SE_MODE_PAGE_BUF			512


/* struct se_hba->hba_flags */
enum hba_flags_table {
	HBA_FLAGS_INTERNAL_USE	= 0x01,
	HBA_FLAGS_PSCSI_MODE	= 0x02,
};

/* struct se_lun->lun_status */
enum transport_lun_status_table {
	TRANSPORT_LUN_STATUS_FREE = 0,
	TRANSPORT_LUN_STATUS_ACTIVE = 1,
};

/* struct se_portal_group->se_tpg_type */
enum transport_tpg_type_table {
	TRANSPORT_TPG_TYPE_NORMAL = 0,
	TRANSPORT_TPG_TYPE_DISCOVERY = 1,
};

/* struct se_task->task_flags */
enum se_task_flags {
	TF_ACTIVE		= (1 << 0),
	TF_SENT			= (1 << 1),
	TF_REQUEST_STOP		= (1 << 2),
	TF_HAS_SENSE		= (1 << 3),
};

/* Special transport agnostic struct se_cmd->t_states */
enum transport_state_table {
	TRANSPORT_NO_STATE	= 0,
	TRANSPORT_NEW_CMD	= 1,
	TRANSPORT_WRITE_PENDING	= 3,
	TRANSPORT_PROCESS_WRITE	= 4,
	TRANSPORT_PROCESSING	= 5,
	TRANSPORT_COMPLETE	= 6,
	TRANSPORT_PROCESS_TMR	= 9,
	TRANSPORT_ISTATE_PROCESSING = 11,
	TRANSPORT_NEW_CMD_MAP	= 16,
	TRANSPORT_COMPLETE_QF_WP = 18,
	TRANSPORT_COMPLETE_QF_OK = 19,
};

/* Used for struct se_cmd->se_cmd_flags */
enum se_cmd_flags_table {
	SCF_SUPPORTED_SAM_OPCODE	= 0x00000001,
	SCF_TRANSPORT_TASK_SENSE	= 0x00000002,
	SCF_EMULATED_TASK_SENSE		= 0x00000004,
	SCF_SCSI_DATA_SG_IO_CDB		= 0x00000008,
	SCF_SCSI_CONTROL_SG_IO_CDB	= 0x00000010,
	SCF_SCSI_NON_DATA_CDB		= 0x00000040,
	SCF_SCSI_CDB_EXCEPTION		= 0x00000080,
	SCF_SCSI_RESERVATION_CONFLICT	= 0x00000100,
	SCF_FUA				= 0x00000200,
	SCF_SE_LUN_CMD			= 0x00000800,
	SCF_SE_ALLOW_EOO		= 0x00001000,
	SCF_BIDI			= 0x00002000,
	SCF_SENT_CHECK_CONDITION	= 0x00004000,
	SCF_OVERFLOW_BIT		= 0x00008000,
	SCF_UNDERFLOW_BIT		= 0x00010000,
	SCF_SENT_DELAYED_TAS		= 0x00020000,
	SCF_ALUA_NON_OPTIMIZED		= 0x00040000,
	SCF_DELAYED_CMD_FROM_SAM_ATTR	= 0x00080000,
	SCF_UNUSED			= 0x00100000,
	SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC = 0x00400000,
};

/* struct se_dev_entry->lun_flags and struct se_lun->lun_access */
enum transport_lunflags_table {
	TRANSPORT_LUNFLAGS_NO_ACCESS		= 0x00,
	TRANSPORT_LUNFLAGS_INITIATOR_ACCESS	= 0x01,
	TRANSPORT_LUNFLAGS_READ_ONLY		= 0x02,
	TRANSPORT_LUNFLAGS_READ_WRITE		= 0x04,
};

/* struct se_device->dev_status */
enum transport_device_status_table {
	TRANSPORT_DEVICE_ACTIVATED		= 0x01,
	TRANSPORT_DEVICE_DEACTIVATED		= 0x02,
	TRANSPORT_DEVICE_QUEUE_FULL		= 0x04,
	TRANSPORT_DEVICE_SHUTDOWN		= 0x08,
	TRANSPORT_DEVICE_OFFLINE_ACTIVATED	= 0x10,
	TRANSPORT_DEVICE_OFFLINE_DEACTIVATED	= 0x20,
};

/*
 * Used by transport_send_check_condition_and_sense() and se_cmd->scsi_sense_reason
 * to signal which ASC/ASCQ sense payload should be built.
 */
enum tcm_sense_reason_table {
	TCM_NON_EXISTENT_LUN			= 0x01,
	TCM_UNSUPPORTED_SCSI_OPCODE		= 0x02,
	TCM_INCORRECT_AMOUNT_OF_DATA		= 0x03,
	TCM_UNEXPECTED_UNSOLICITED_DATA		= 0x04,
	TCM_SERVICE_CRC_ERROR			= 0x05,
	TCM_SNACK_REJECTED			= 0x06,
	TCM_SECTOR_COUNT_TOO_MANY		= 0x07,
	TCM_INVALID_CDB_FIELD			= 0x08,
	TCM_INVALID_PARAMETER_LIST		= 0x09,
	TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE	= 0x0a,
	TCM_UNKNOWN_MODE_PAGE			= 0x0b,
	TCM_WRITE_PROTECTED			= 0x0c,
	TCM_CHECK_CONDITION_ABORT_CMD		= 0x0d,
	TCM_CHECK_CONDITION_UNIT_ATTENTION	= 0x0e,
	TCM_CHECK_CONDITION_NOT_READY		= 0x0f,
	TCM_RESERVATION_CONFLICT		= 0x10,
};

enum target_sc_flags_table {
	TARGET_SCF_BIDI_OP		= 0x01,
	TARGET_SCF_ACK_KREF		= 0x02,
};

/* fabric independent task management function values */
enum tcm_tmreq_table {
	TMR_ABORT_TASK		= 1,
	TMR_ABORT_TASK_SET	= 2,
	TMR_CLEAR_ACA		= 3,
	TMR_CLEAR_TASK_SET	= 4,
	TMR_LUN_RESET		= 5,
	TMR_TARGET_WARM_RESET	= 6,
	TMR_TARGET_COLD_RESET	= 7,
	TMR_FABRIC_TMR		= 255,
};

/* fabric independent task management response values */
enum tcm_tmrsp_table {
	TMR_FUNCTION_COMPLETE		= 0,
	TMR_TASK_DOES_NOT_EXIST		= 1,
	TMR_LUN_DOES_NOT_EXIST		= 2,
	TMR_TASK_STILL_ALLEGIANT	= 3,
	TMR_TASK_FAILOVER_NOT_SUPPORTED	= 4,
	TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED	= 5,
	TMR_FUNCTION_AUTHORIZATION_FAILED = 6,
	TMR_FUNCTION_REJECTED		= 255,
};

struct se_obj {
	atomic_t obj_access_count;
};

/*
 * Used by TCM Core internally to signal if ALUA emulation is enabled or
 * disabled, or running in with TCM/pSCSI passthrough mode
 */
typedef enum {
	SPC_ALUA_PASSTHROUGH,
	SPC2_ALUA_DISABLED,
	SPC3_ALUA_EMULATED
} t10_alua_index_t;

/*
 * Used by TCM Core internally to signal if SAM Task Attribute emulation
 * is enabled or disabled, or running in with TCM/pSCSI passthrough mode
 */
typedef enum {
	SAM_TASK_ATTR_PASSTHROUGH,
	SAM_TASK_ATTR_UNTAGGED,
	SAM_TASK_ATTR_EMULATED
} t10_task_attr_index_t;

/*
 * Used for target SCSI statistics
 */
typedef enum {
	SCSI_INST_INDEX,
	SCSI_DEVICE_INDEX,
	SCSI_AUTH_INTR_INDEX,
	SCSI_INDEX_TYPE_MAX
} scsi_index_t;

struct se_cmd;

struct t10_alua {
	t10_alua_index_t alua_type;
	/* ALUA Target Port Group ID */
	u16	alua_tg_pt_gps_counter;
	u32	alua_tg_pt_gps_count;
	spinlock_t tg_pt_gps_lock;
	struct se_subsystem_dev *t10_sub_dev;
	/* Used for default ALUA Target Port Group */
	struct t10_alua_tg_pt_gp *default_tg_pt_gp;
	/* Used for default ALUA Target Port Group ConfigFS group */
	struct config_group alua_tg_pt_gps_group;
	int (*alua_state_check)(struct se_cmd *, unsigned char *, u8 *);
	struct list_head tg_pt_gps_list;
};

struct t10_alua_lu_gp {
	u16	lu_gp_id;
	int	lu_gp_valid_id;
	u32	lu_gp_members;
	atomic_t lu_gp_ref_cnt;
	spinlock_t lu_gp_lock;
	struct config_group lu_gp_group;
	struct list_head lu_gp_node;
	struct list_head lu_gp_mem_list;
};

struct t10_alua_lu_gp_member {
	bool lu_gp_assoc;
	atomic_t lu_gp_mem_ref_cnt;
	spinlock_t lu_gp_mem_lock;
	struct t10_alua_lu_gp *lu_gp;
	struct se_device *lu_gp_mem_dev;
	struct list_head lu_gp_mem_list;
};

struct t10_alua_tg_pt_gp {
	u16	tg_pt_gp_id;
	int	tg_pt_gp_valid_id;
	int	tg_pt_gp_alua_access_status;
	int	tg_pt_gp_alua_access_type;
	int	tg_pt_gp_nonop_delay_msecs;
	int	tg_pt_gp_trans_delay_msecs;
	int	tg_pt_gp_pref;
	int	tg_pt_gp_write_metadata;
	/* Used by struct t10_alua_tg_pt_gp->tg_pt_gp_md_buf_len */
#define ALUA_MD_BUF_LEN				1024
	u32	tg_pt_gp_md_buf_len;
	u32	tg_pt_gp_members;
	atomic_t tg_pt_gp_alua_access_state;
	atomic_t tg_pt_gp_ref_cnt;
	spinlock_t tg_pt_gp_lock;
	struct mutex tg_pt_gp_md_mutex;
	struct se_subsystem_dev *tg_pt_gp_su_dev;
	struct config_group tg_pt_gp_group;
	struct list_head tg_pt_gp_list;
	struct list_head tg_pt_gp_mem_list;
};

struct t10_alua_tg_pt_gp_member {
	bool tg_pt_gp_assoc;
	atomic_t tg_pt_gp_mem_ref_cnt;
	spinlock_t tg_pt_gp_mem_lock;
	struct t10_alua_tg_pt_gp *tg_pt_gp;
	struct se_port *tg_pt;
	struct list_head tg_pt_gp_mem_list;
};

struct t10_vpd {
	unsigned char device_identifier[INQUIRY_VPD_DEVICE_IDENTIFIER_LEN];
	int protocol_identifier_set;
	u32 protocol_identifier;
	u32 device_identifier_code_set;
	u32 association;
	u32 device_identifier_type;
	struct list_head vpd_list;
};

struct t10_wwn {
	char vendor[8];
	char model[16];
	char revision[4];
	char unit_serial[INQUIRY_VPD_SERIAL_LEN];
	spinlock_t t10_vpd_lock;
	struct se_subsystem_dev *t10_sub_dev;
	struct config_group t10_wwn_group;
	struct list_head t10_vpd_list;
};


/*
 * Used by TCM Core internally to signal if >= SPC-3 persistent reservations
 * emulation is enabled or disabled, or running in with TCM/pSCSI passthrough
 * mode
 */
typedef enum {
	SPC_PASSTHROUGH,
	SPC2_RESERVATIONS,
	SPC3_PERSISTENT_RESERVATIONS
} t10_reservations_index_t;

struct t10_pr_registration {
	/* Used for fabrics that contain WWN+ISID */
#define PR_REG_ISID_LEN				16
	/* PR_REG_ISID_LEN + ',i,0x' */
#define PR_REG_ISID_ID_LEN			(PR_REG_ISID_LEN + 5)
	char pr_reg_isid[PR_REG_ISID_LEN];
	/* Used during APTPL metadata reading */
#define PR_APTPL_MAX_IPORT_LEN			256
	unsigned char pr_iport[PR_APTPL_MAX_IPORT_LEN];
	/* Used during APTPL metadata reading */
#define PR_APTPL_MAX_TPORT_LEN			256
	unsigned char pr_tport[PR_APTPL_MAX_TPORT_LEN];
	/* For writing out live meta data */
	unsigned char *pr_aptpl_buf;
	u16 pr_aptpl_rpti;
	u16 pr_reg_tpgt;
	/* Reservation effects all target ports */
	int pr_reg_all_tg_pt;
	/* Activate Persistence across Target Power Loss */
	int pr_reg_aptpl;
	int pr_res_holder;
	int pr_res_type;
	int pr_res_scope;
	/* Used for fabric initiator WWPNs using a ISID */
	bool isid_present_at_reg;
	u32 pr_res_mapped_lun;
	u32 pr_aptpl_target_lun;
	u32 pr_res_generation;
	u64 pr_reg_bin_isid;
	u64 pr_res_key;
	atomic_t pr_res_holders;
	struct se_node_acl *pr_reg_nacl;
	struct se_dev_entry *pr_reg_deve;
	struct se_lun *pr_reg_tg_pt_lun;
	struct list_head pr_reg_list;
	struct list_head pr_reg_abort_list;
	struct list_head pr_reg_aptpl_list;
	struct list_head pr_reg_atp_list;
	struct list_head pr_reg_atp_mem_list;
};

/*
 * This set of function pointer ops is set based upon SPC3_PERSISTENT_RESERVATIONS,
 * SPC2_RESERVATIONS or SPC_PASSTHROUGH in drivers/target/target_core_pr.c:
 * core_setup_reservations()
 */
struct t10_reservation_ops {
	int (*t10_reservation_check)(struct se_cmd *, u32 *);
	int (*t10_seq_non_holder)(struct se_cmd *, unsigned char *, u32);
	int (*t10_pr_register)(struct se_cmd *);
	int (*t10_pr_clear)(struct se_cmd *);
};

struct t10_reservation {
	/* Reservation effects all target ports */
	int pr_all_tg_pt;
	/* Activate Persistence across Target Power Loss enabled
	 * for SCSI device */
	int pr_aptpl_active;
	/* Used by struct t10_reservation->pr_aptpl_buf_len */
#define PR_APTPL_BUF_LEN			8192
	u32 pr_aptpl_buf_len;
	u32 pr_generation;
	t10_reservations_index_t res_type;
	spinlock_t registration_lock;
	spinlock_t aptpl_reg_lock;
	/*
	 * This will always be set by one individual I_T Nexus.
	 * However with all_tg_pt=1, other I_T Nexus from the
	 * same initiator can access PR reg/res info on a different
	 * target port.
	 *
	 * There is also the 'All Registrants' case, where there is
	 * a single *pr_res_holder of the reservation, but all
	 * registrations are considered reservation holders.
	 */
	struct se_node_acl *pr_res_holder;
	struct list_head registration_list;
	struct list_head aptpl_reg_list;
	struct t10_reservation_ops pr_ops;
};

struct se_queue_req {
	int			state;
	struct se_cmd		*cmd;
	struct list_head	qr_list;
};

struct se_queue_obj {
	atomic_t		queue_cnt;
	spinlock_t		cmd_queue_lock;
	struct list_head	qobj_list;
	wait_queue_head_t	thread_wq;
};

struct se_task {
	unsigned long long	task_lba;
	u32			task_sectors;
	u32			task_size;
	struct se_cmd		*task_se_cmd;
	struct scatterlist	*task_sg;
	u32			task_sg_nents;
	u16			task_flags;
	u8			task_scsi_status;
	enum dma_data_direction	task_data_direction;
	struct list_head	t_list;
	struct list_head	t_execute_list;
	struct list_head	t_state_list;
	bool			t_state_active;
	struct completion	task_stop_comp;
};

struct se_cmd {
	/* SAM response code being sent to initiator */
	u8			scsi_status;
	u8			scsi_asc;
	u8			scsi_ascq;
	u8			scsi_sense_reason;
	u16			scsi_sense_length;
	/* Delay for ALUA Active/NonOptimized state access in milliseconds */
	int			alua_nonop_delay;
	/* See include/linux/dma-mapping.h */
	enum dma_data_direction	data_direction;
	/* For SAM Task Attribute */
	int			sam_task_attr;
	/* Transport protocol dependent state, see transport_state_table */
	enum transport_state_table t_state;
	/* Used to signal cmd->se_tfo->check_release_cmd() usage per cmd */
	unsigned		check_release:1;
	unsigned		cmd_wait_set:1;
	/* See se_cmd_flags_table */
	u32			se_cmd_flags;
	u32			se_ordered_id;
	/* Total size in bytes associated with command */
	u32			data_length;
	/* SCSI Presented Data Transfer Length */
	u32			cmd_spdtl;
	u32			residual_count;
	u32			orig_fe_lun;
	/* Persistent Reservation key */
	u64			pr_res_key;
	/* Used for sense data */
	void			*sense_buffer;
	struct list_head	se_delayed_node;
	struct list_head	se_lun_node;
	struct list_head	se_qf_node;
	struct se_device      *se_dev;
	struct se_dev_entry   *se_deve;
	struct se_lun		*se_lun;
	/* Only used for internal passthrough and legacy TCM fabric modules */
	struct se_session	*se_sess;
	struct se_tmr_req	*se_tmr_req;
	struct list_head	se_queue_node;
	struct list_head	se_cmd_list;
	struct completion	cmd_wait_comp;
	struct kref		cmd_kref;
	struct target_core_fabric_ops *se_tfo;
	int (*execute_task)(struct se_task *);
	void (*transport_complete_callback)(struct se_cmd *);

	unsigned char		*t_task_cdb;
	unsigned char		__t_task_cdb[TCM_MAX_COMMAND_SIZE];
	unsigned long long	t_task_lba;
	int			t_tasks_failed;
	u32			t_tasks_sg_chained_no;
	atomic_t		t_fe_count;
	atomic_t		t_se_count;
	atomic_t		t_task_cdbs_left;
	atomic_t		t_task_cdbs_ex_left;
	atomic_t		t_task_cdbs_sent;
	atomic_t		t_transport_aborted;
	atomic_t		t_transport_active;
	atomic_t		t_transport_complete;
	atomic_t		t_transport_queue_active;
	atomic_t		t_transport_sent;
	atomic_t		t_transport_stop;
	atomic_t		transport_dev_active;
	atomic_t		transport_lun_active;
	atomic_t		transport_lun_fe_stop;
	atomic_t		transport_lun_stop;
	spinlock_t		t_state_lock;
	struct completion	t_transport_stop_comp;
	struct completion	transport_lun_fe_stop_comp;
	struct completion	transport_lun_stop_comp;
	struct scatterlist	*t_tasks_sg_chained;

	struct work_struct	work;

	struct scatterlist	*t_data_sg;
	unsigned int		t_data_nents;
	void			*t_data_vmap;
	struct scatterlist	*t_bidi_data_sg;
	unsigned int		t_bidi_data_nents;

	/* Used for BIDI READ */
	struct list_head	t_task_list;
	u32			t_task_list_num;

};

struct se_tmr_req {
	/* Task Management function to be preformed */
	u8			function;
	/* Task Management response to send */
	u8			response;
	int			call_transport;
	/* Reference to ITT that Task Mgmt should be preformed */
	u32			ref_task_tag;
	/* 64-bit encoded SAM LUN from $FABRIC_MOD TMR header */
	u64			ref_task_lun;
	void 			*fabric_tmr_ptr;
	struct se_cmd		*task_cmd;
	struct se_cmd		*ref_cmd;
	struct se_device	*tmr_dev;
	struct se_lun		*tmr_lun;
	struct list_head	tmr_list;
};

struct se_ua {
	u8			ua_asc;
	u8			ua_ascq;
	struct se_node_acl	*ua_nacl;
	struct list_head	ua_dev_list;
	struct list_head	ua_nacl_list;
};

struct se_node_acl {
	char			initiatorname[TRANSPORT_IQN_LEN];
	/* Used to signal demo mode created ACL, disabled by default */
	bool			dynamic_node_acl;
	u32			queue_depth;
	u32			acl_index;
	u64			num_cmds;
	u64			read_bytes;
	u64			write_bytes;
	spinlock_t		stats_lock;
	/* Used for PR SPEC_I_PT=1 and REGISTER_AND_MOVE */
	atomic_t		acl_pr_ref_count;
	struct se_dev_entry	*device_list;
	struct se_session	*nacl_sess;
	struct se_portal_group *se_tpg;
	spinlock_t		device_list_lock;
	spinlock_t		nacl_sess_lock;
	struct config_group	acl_group;
	struct config_group	acl_attrib_group;
	struct config_group	acl_auth_group;
	struct config_group	acl_param_group;
	struct config_group	acl_fabric_stat_group;
	struct config_group	*acl_default_groups[5];
	struct list_head	acl_list;
	struct list_head	acl_sess_list;
};

struct se_session {
	unsigned		sess_tearing_down:1;
	u64			sess_bin_isid;
	struct se_node_acl	*se_node_acl;
	struct se_portal_group *se_tpg;
	void			*fabric_sess_ptr;
	struct list_head	sess_list;
	struct list_head	sess_acl_list;
	struct list_head	sess_cmd_list;
	struct list_head	sess_wait_list;
	spinlock_t		sess_cmd_lock;
};

struct se_device;
struct se_transform_info;
struct scatterlist;

struct se_ml_stat_grps {
	struct config_group	stat_group;
	struct config_group	scsi_auth_intr_group;
	struct config_group	scsi_att_intr_port_group;
};

struct se_lun_acl {
	char			initiatorname[TRANSPORT_IQN_LEN];
	u32			mapped_lun;
	struct se_node_acl	*se_lun_nacl;
	struct se_lun		*se_lun;
	struct list_head	lacl_list;
	struct config_group	se_lun_group;
	struct se_ml_stat_grps	ml_stat_grps;
};

struct se_dev_entry {
	bool			def_pr_registered;
	/* See transport_lunflags_table */
	u32			lun_flags;
	u32			deve_cmds;
	u32			mapped_lun;
	u32			average_bytes;
	u32			last_byte_count;
	u32			total_cmds;
	u32			total_bytes;
	u64			pr_res_key;
	u64			creation_time;
	u32			attach_count;
	u64			read_bytes;
	u64			write_bytes;
	atomic_t		ua_count;
	/* Used for PR SPEC_I_PT=1 and REGISTER_AND_MOVE */
	atomic_t		pr_ref_count;
	struct se_lun_acl	*se_lun_acl;
	spinlock_t		ua_lock;
	struct se_lun		*se_lun;
	struct list_head	alua_port_list;
	struct list_head	ua_list;
};

struct se_dev_limits {
	/* Max supported HW queue depth */
	u32		hw_queue_depth;
	/* Max supported virtual queue depth */
	u32		queue_depth;
	/* From include/linux/blkdev.h for the other HW/SW limits. */
	struct queue_limits limits;
};

struct se_dev_attrib {
	int		emulate_dpo;
	int		emulate_fua_write;
	int		emulate_fua_read;
	int		emulate_write_cache;
	int		emulate_ua_intlck_ctrl;
	int		emulate_tas;
	int		emulate_tpu;
	int		emulate_tpws;
	int		emulate_reservations;
	int		emulate_alua;
	int		enforce_pr_isids;
	int		is_nonrot;
	int		emulate_rest_reord;
	u32		hw_block_size;
	u32		block_size;
	u32		hw_max_sectors;
	u32		max_sectors;
	u32		optimal_sectors;
	u32		hw_queue_depth;
	u32		queue_depth;
	u32		max_unmap_lba_count;
	u32		max_unmap_block_desc_count;
	u32		unmap_granularity;
	u32		unmap_granularity_alignment;
	struct se_subsystem_dev *da_sub_dev;
	struct config_group da_group;
};

struct se_dev_stat_grps {
	struct config_group stat_group;
	struct config_group scsi_dev_group;
	struct config_group scsi_tgt_dev_group;
	struct config_group scsi_lu_group;
};

struct se_subsystem_dev {
/* Used for struct se_subsystem_dev-->se_dev_alias, must be less than PAGE_SIZE */
#define SE_DEV_ALIAS_LEN		512
	unsigned char	se_dev_alias[SE_DEV_ALIAS_LEN];
/* Used for struct se_subsystem_dev->se_dev_udev_path[], must be less than PAGE_SIZE */
#define SE_UDEV_PATH_LEN		512
	unsigned char	se_dev_udev_path[SE_UDEV_PATH_LEN];
	u32		su_dev_flags;
	struct se_hba *se_dev_hba;
	struct se_device *se_dev_ptr;
	struct se_dev_attrib se_dev_attrib;
	/* T10 Asymmetric Logical Unit Assignment for Target Ports */
	struct t10_alua	t10_alua;
	/* T10 Inquiry and VPD WWN Information */
	struct t10_wwn	t10_wwn;
	/* T10 SPC-2 + SPC-3 Reservations */
	struct t10_reservation t10_pr;
	spinlock_t      se_dev_lock;
	void            *se_dev_su_ptr;
	struct config_group se_dev_group;
	/* For T10 Reservations */
	struct config_group se_dev_pr_group;
	/* For target_core_stat.c groups */
	struct se_dev_stat_grps dev_stat_grps;
};

struct se_device {
	/* RELATIVE TARGET PORT IDENTIFER Counter */
	u16			dev_rpti_counter;
	/* Used for SAM Task Attribute ordering */
	u32			dev_cur_ordered_id;
	u32			dev_flags;
	u32			dev_port_count;
	/* See transport_device_status_table */
	u32			dev_status;
	/* Physical device queue depth */
	u32			queue_depth;
	/* Used for SPC-2 reservations enforce of ISIDs */
	u64			dev_res_bin_isid;
	t10_task_attr_index_t	dev_task_attr_type;
	/* Pointer to transport specific device structure */
	void 			*dev_ptr;
	u32			dev_index;
	u64			creation_time;
	u32			num_resets;
	u64			num_cmds;
	u64			read_bytes;
	u64			write_bytes;
	spinlock_t		stats_lock;
	/* Active commands on this virtual SE device */
	atomic_t		simple_cmds;
	atomic_t		dev_ordered_id;
	atomic_t		execute_tasks;
	atomic_t		dev_ordered_sync;
	atomic_t		dev_qf_count;
	struct se_obj		dev_obj;
	struct se_obj		dev_access_obj;
	struct se_obj		dev_export_obj;
	struct se_queue_obj	dev_queue_obj;
	spinlock_t		delayed_cmd_lock;
	spinlock_t		execute_task_lock;
	spinlock_t		dev_reservation_lock;
	spinlock_t		dev_status_lock;
	spinlock_t		se_port_lock;
	spinlock_t		se_tmr_lock;
	spinlock_t		qf_cmd_lock;
	/* Used for legacy SPC-2 reservationsa */
	struct se_node_acl	*dev_reserved_node_acl;
	/* Used for ALUA Logical Unit Group membership */
	struct t10_alua_lu_gp_member *dev_alua_lu_gp_mem;
	/* Used for SPC-3 Persistent Reservations */
	struct t10_pr_registration *dev_pr_res_holder;
	struct list_head	dev_sep_list;
	struct list_head	dev_tmr_list;
	/* Pointer to descriptor for processing thread */
	struct task_struct	*process_thread;
	struct work_struct	qf_work_queue;
	struct list_head	delayed_cmd_list;
	struct list_head	execute_task_list;
	struct list_head	state_task_list;
	struct list_head	qf_cmd_list;
	/* Pointer to associated SE HBA */
	struct se_hba		*se_hba;
	struct se_subsystem_dev *se_sub_dev;
	/* Pointer to template of function pointers for transport */
	struct se_subsystem_api *transport;
	/* Linked list for struct se_hba struct se_device list */
	struct list_head	dev_list;
};

struct se_hba {
	u16			hba_tpgt;
	u32			hba_id;
	/* See hba_flags_table */
	u32			hba_flags;
	/* Virtual iSCSI devices attached. */
	u32			dev_count;
	u32			hba_index;
	/* Pointer to transport specific host structure. */
	void			*hba_ptr;
	/* Linked list for struct se_device */
	struct list_head	hba_dev_list;
	struct list_head	hba_node;
	spinlock_t		device_lock;
	struct config_group	hba_group;
	struct mutex		hba_access_mutex;
	struct se_subsystem_api *transport;
};

struct se_port_stat_grps {
	struct config_group stat_group;
	struct config_group scsi_port_group;
	struct config_group scsi_tgt_port_group;
	struct config_group scsi_transport_group;
};

struct se_lun {
	/* See transport_lun_status_table */
	enum transport_lun_status_table lun_status;
	u32			lun_access;
	u32			lun_flags;
	u32			unpacked_lun;
	atomic_t		lun_acl_count;
	spinlock_t		lun_acl_lock;
	spinlock_t		lun_cmd_lock;
	spinlock_t		lun_sep_lock;
	struct completion	lun_shutdown_comp;
	struct list_head	lun_cmd_list;
	struct list_head	lun_acl_list;
	struct se_device	*lun_se_dev;
	struct se_port		*lun_sep;
	struct config_group	lun_group;
	struct se_port_stat_grps port_stat_grps;
};

struct scsi_port_stats {
       u64     cmd_pdus;
       u64     tx_data_octets;
       u64     rx_data_octets;
};

struct se_port {
	/* RELATIVE TARGET PORT IDENTIFER */
	u16		sep_rtpi;
	int		sep_tg_pt_secondary_stat;
	int		sep_tg_pt_secondary_write_md;
	u32		sep_index;
	struct scsi_port_stats sep_stats;
	/* Used for ALUA Target Port Groups membership */
	atomic_t	sep_tg_pt_secondary_offline;
	/* Used for PR ALL_TG_PT=1 */
	atomic_t	sep_tg_pt_ref_cnt;
	spinlock_t	sep_alua_lock;
	struct mutex	sep_tg_pt_md_mutex;
	struct t10_alua_tg_pt_gp_member *sep_alua_tg_pt_gp_mem;
	struct se_lun *sep_lun;
	struct se_portal_group *sep_tpg;
	struct list_head sep_alua_list;
	struct list_head sep_list;
};

struct se_tpg_np {
	struct se_portal_group *tpg_np_parent;
	struct config_group	tpg_np_group;
};

struct se_portal_group {
	/* Type of target portal group, see transport_tpg_type_table */
	enum transport_tpg_type_table se_tpg_type;
	/* Number of ACLed Initiator Nodes for this TPG */
	u32			num_node_acls;
	/* Used for PR SPEC_I_PT=1 and REGISTER_AND_MOVE */
	atomic_t		tpg_pr_ref_count;
	/* Spinlock for adding/removing ACLed Nodes */
	spinlock_t		acl_node_lock;
	/* Spinlock for adding/removing sessions */
	spinlock_t		session_lock;
	spinlock_t		tpg_lun_lock;
	/* Pointer to $FABRIC_MOD portal group */
	void			*se_tpg_fabric_ptr;
	struct list_head	se_tpg_node;
	/* linked list for initiator ACL list */
	struct list_head	acl_node_list;
	struct se_lun		*tpg_lun_list;
	struct se_lun		tpg_virt_lun0;
	/* List of TCM sessions associated wth this TPG */
	struct list_head	tpg_sess_list;
	/* Pointer to $FABRIC_MOD dependent code */
	struct target_core_fabric_ops *se_tpg_tfo;
	struct se_wwn		*se_tpg_wwn;
	struct config_group	tpg_group;
	struct config_group	*tpg_default_groups[6];
	struct config_group	tpg_lun_group;
	struct config_group	tpg_np_group;
	struct config_group	tpg_acl_group;
	struct config_group	tpg_attrib_group;
	struct config_group	tpg_param_group;
};

struct se_wwn {
	struct target_fabric_configfs *wwn_tf;
	struct config_group	wwn_group;
	struct config_group	*wwn_default_groups[2];
	struct config_group	fabric_stat_group;
};

#endif /* TARGET_CORE_BASE_H */