iscsi_target.h

iscsi源代码 UNH的progect 有initiator端和target端的源码

/*	target/iscsi_target.h

	vi: set autoindent tabstop=8 shiftwidth=8 :

	header file for the iSCSI Target

*/
/*
	Copyright (C) 2001-2003 InterOperability Lab (IOL)
					University of New Hampshier (UNH)
					Durham, NH 03824

	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, 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.

	The name of IOL and/or UNH may not be used to endorse or promote products
	derived from this software without specific prior written permission.
*/

#ifndef	_ISCSI_TARGET_H
#define	_ISCSI_TARGET_H

#include "scsi_target.h"
#include <linux/proc_fs.h>

#include "../common/iscsi_common.h"
#include "../common/debug.h"
#include "../common/my_memory.h"
#include "../common/range.h"
#include "../common/crc.h"
#include "../common/tcp_utilities.h"

/* chap and srp support - CHONG */
#include "../security/misc/misc_func.h"
#include "../security/chap/chap.h"
#include "../security/srp/srp.h"

#include "../common/text_param.h"
#include "../common/target_negotiate.h"
#include "iscsi_portal_group.h"


struct data_list
{
	__u32 offset;
	__u32 length;
	char *buffer;
	struct data_list *next;
};

/* values for "state" in struct iscsi_cmnd */
#define ISCSI_CMND_RECEIVED			1
#define ISCSI_NEW_CMND				2
#define ISCSI_BUFFER_RDY			3
#define ISCSI_DONE				4
#define ISCSI_SENT				5
#define ISCSI_DEQUEUE				6
#define ISCSI_ALL_R2TS_SENT			7
#define ISCSI_IMMEDIATE_DATA_IN			8
#define ISCSI_UNSOLICITED_DATA_IN		9
#define ISCSI_DATA_IN				10
#define ISCSI_MGT_FN_DONE			11
#define ISCSI_SEND_TEXT_RESPONSE		12
#define ISCSI_LOGOUT				13
#define ISCSI_PING				14
#define ISCSI_QUEUE_CMND			15
#define ISCSI_QUEUE_CMND_RDY			16
#define ISCSI_QUEUE_OTHER			17
#define ISCSI_NOPIN_SENT			18
#define ISCSI_RESEND_STATUS			19
#define ISCSI_ASK_FOR_MORE_TEXT			20
#define ISCSI_AWAIT_MORE_TEXT			21
#define ISCSI_BLOCKED_SENDING_TEXT		22

/* stores everything related to a SCSI command received */
struct iscsi_cmnd
{
  /* next: pointer to the next command in the list */
  struct iscsi_cmnd	*next;

  /* conn: connection on which this command was received */
  struct iscsi_conn	*conn;

  /* session: session on which this command was received */
  struct iscsi_session	*session;

  /* unsolicited_data_sem: to control receiving immediate data */
  struct semaphore    	unsolicited_data_sem;

  /* state: execution state of the command */
  __u8			state;

  /* response: task_mgt_function response */
  __u8			response;

  /* flag for errorRecovery of r2t */
  __u8 			recovery_r2t;

  /* flags from command pdu */
  __u8			command_flags;

  /* ping_data: data get from nopout and send for nopin */
  char			*ping_data;

  /* in_progress_buffer: accumulated data during text negotiations */
  char			*in_progress_buffer;

  /* cmnd: cmnd corresponding to this struct */
  Target_Scsi_Cmnd	*cmnd;

  /* message: message corresponding to this struct */
  Target_Scsi_Message 	*message;

  /* immediate_data_present: */
  __u8    		immediate_data_present;

  /* unsolicited_data_present: */
  __u8    		unsolicited_data_present;

  /* Data PDU re-transmission on Data SNACK - SAI */
  __u8                  retransmit_flg;

  /* opcode_byte: command's opcode byte (including I bit) */
  __u8                  opcode_byte;

  /* data_length: total number of bytes of data to be transferred by command */
  __u32			data_length;

  /* first_burst_size: data associated with the command */
  __u32			first_burst_len;

  /* max_burst_size: data associated with one R2T */
  __u32			next_burst_len;

  /* data_done: number of bytes of data transferred so far in a command */
  __u32			data_done;

  /* r2t_data_total: total amount of data to be solicited by r2ts */
  int			r2t_data_total;

  /* r2t_data: data_length_left for the next r2t -- can go negative! */
  int			r2t_data;

  /* scatter_list_offset:when processing a WRITE command, is byte offset in
   *			 current sg list item of where to start storing next
   *			 data byte from a DataOut pdu if pdus, seqs are in order
   *			 when processing a READ command, is byte offset in
   *			 current sg list iemt of where to start sending next
   *			 data byte in a DataOut pdu if pdus, seqs are in order
   */
  __u32           	scatter_list_offset;

  /* scatter_entry_count:when processing a WRITE command, is index into
   *			 current sg list of item of where to start storing next
   *			 data byte from a DataOut pdu if pdus, seqs are in order
   *			 when processing a READ command, is byte offset in
   *			 current sg list item of where to start sending next
   *			 data byte in a DataOut pdu if pdus, seqs are in order
   */
  __u32           	scatter_list_count;

  /* init_task_tag: Initiator Tag */
  __u32			init_task_tag;

  /* target_xfer_tag: Target Assigned Tag */
  __u32			target_xfer_tag;

  /* ref_task_tag: Referenced Task Tag used when aborting tasks*/
  __u32           	ref_task_tag;

  /* ref_cmd_sn: Referenced command sn used when aborting command*/
  __u32           	ref_cmd_sn;

  /* ref_function: Referenced function for task management */
  __u32			ref_function;

  /* ref_task_lun: Referenced Task lun used when aborting luns*/
  __u64           	ref_task_lun;

  /* lun and cdb: as their name mean */
  __u64   lun;
  __u8    cdb[16];	

  /* cmd_sn of this command and stat_sn of this command response */
  __u32			cmd_sn;
  __u32			stat_sn;
  __u32			cmd_sn_increment;   /* used by SCSI Command pdus only */

  /* Command WIDE COUNTERS: data_sn and r2t_sn */
  __u32			data_sn;
  __u32			r2t_sn;
  __u32			outstanding_r2t;

  /* for out-of-order sequence and DataOut PDUs */
  struct order_range      seq_range_list;
  struct order_range      pdu_range_list;
      
  /* for out-of-order command */
  __u8			 hdr[ISCSI_HDR_LEN];
  struct data_list	*unsolicited_data_head;
  struct data_list	*unsolicited_data_tail;

  /* Added r2t cookie details - SAI */
  struct iscsi_cookie	*first_r2t_cookie;
  struct iscsi_cookie	*last_r2t_cookie;

  /* queue out-of-order data pdus - SAI */
  struct iscsi_cookie	*first_data_q;
  struct iscsi_cookie	*last_data_q;

  /* Added timestamp for r2t retransmissions - SAI */
  int		timestamp;

  /* Store the previously sent data_sn, used when retransmit_flg set */
  __u32		prev_data_sn;

  /* Store the retransmission limits for data_sn set by a SNACK,
   * used when retransmit_flg set */
  __u32		startsn, endsn;

};


extern struct iscsi_global *devdata;

int	iscsi_detect		(Scsi_Target_Template*);
int	iscsi_release		(Scsi_Target_Device*);
int	iscsi_xmit_response	(Target_Scsi_Cmnd*);
int	iscsi_rdy_to_xfer	(Target_Scsi_Cmnd*);
int 	iscsi_proc_info		(char *, char **, off_t, int, int, int);
void 	iscsi_task_mgt_fn_done 	(Target_Scsi_Message *msg);

int	iscsi_server_thread (void*);
int	iscsi_rx_thread	(void*);
int	iscsi_tx_thread (void*);

    
#define PDU_SENSE_LENGTH_SIZE 2
#define SENSE_STRUCTURE_SIZE 18


/*
 * executed only by the rx thread, in spite of the tx in the name!
 * iscsi_tx_reject: this function transmits a reject to the Initiator
 * the attached 48-byte data segment is the header of the rejected PDU
 * OUTPUT: 0 if everything is okay, < 0 if there is trouble
 */
int
iscsi_tx_rjt(struct iscsi_conn *conn, __u8 *bad_hdr, __u8 reason);

/*
 * executed only by the rx thread.
 * Allocates new reject item, fills it in with header of rejected pdu,
 * and enqueues it for tx thread on reject_list of this connection.
 */
int
enqueue_reject(struct iscsi_conn *conn, __u8 reason);


/*
 * find_iovec_needed: this function returns the number of iovecs that
 * are needed to receive some data
 * INPUT: amount of data needed, pointer to scattergather list (from the
 * 	  point where the data is to start for this round, offset within
 * 	  the first scattergather element - in case it was not used up
 * 	  completely
 * OUTPUT: number of iovectors needed, else < 0 if there is trouble
 */
int __attribute__ ((no_instrument_function))
find_iovec_needed (__u32 data_len, 
	struct scatterlist *st_list, __u32 offset);


/*
 * fill_iovec: This function fills in a given iovec structure so as to
 * reflect a given scattergather list upto the length that is required
 * No checks are made on the length on the iovec given except that it
 * needs to be greater than the size needed. Also, the scatterlist is
 * also not checked. The integer offset upon return reflects the posn of
 * the offset in the last scatterlist that was used for this function
 * INPUT: struct iovec, no. of iovecs, scatterlist, ptr to offset within
 * 	  the first element, and the total length required
 * OUTPUT: how many st_list elements are used, < 0 if there is trouble
 */
int __attribute__ ((no_instrument_function))
fill_iovec (struct iovec *iov, int i, int niov, 
       struct scatterlist *st_list, int *offset, __u32 data);


/*
 * iscsi_rx_data: will receive a fixed amount of data.
 * INPUT: struct iscsi_conn (what connection), struct iovec, number of iovecs,
 * total amount of data in bytes
 * OUTPUT: int total bytes read if everything is okay
 * 	       < 0 if trouble
 */
int iscsi_rx_data (struct iscsi_conn *conn, struct iovec *iov, int niov, int data);


/*
 * iscsi_tx_data: will transmit a fixed amount of data.
 * INPUT: struct iscsi_conn (what connection), struct iovec, number of iovecs,
 * total amount of data in bytes,
 * OUTPUT: int total bytes read if everything is okay
 * 	       < 0 if trouble
 */
int iscsi_tx_data (struct iscsi_conn *conn, struct iovec *iov, int niov, int data);
				
#endif