linux/include/scsi/libiscsi.h
Jayamohan Kallickal b8b9e1b812 [SCSI] libiscsi: iscsi_session_setup to allow for private space
This patch contains changes that allow iscsi_session_setup
to allocate private space for LLD's

Signed-off-by: Jayamohan Kallickal <jayamohank@serverengines.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-10-02 14:01:39 -05:00

447 lines
13 KiB
C

/*
* iSCSI lib definitions
*
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* Copyright (C) 2004 - 2006 Mike Christie
* Copyright (C) 2004 - 2005 Dmitry Yusupov
* Copyright (C) 2004 - 2005 Alex Aizman
*
* 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.
*/
#ifndef LIBISCSI_H
#define LIBISCSI_H
#include <linux/types.h>
#include <linux/wait.h>
#include <linux/mutex.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <scsi/iscsi_proto.h>
#include <scsi/iscsi_if.h>
#include <scsi/scsi_transport_iscsi.h>
struct scsi_transport_template;
struct scsi_host_template;
struct scsi_device;
struct Scsi_Host;
struct scsi_target;
struct scsi_cmnd;
struct socket;
struct iscsi_transport;
struct iscsi_cls_session;
struct iscsi_cls_conn;
struct iscsi_session;
struct iscsi_nopin;
struct device;
#define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
#define ISCSI_MGMT_CMDS_MAX 15
#define ISCSI_DEF_CMD_PER_LUN 32
/* Task Mgmt states */
enum {
TMF_INITIAL,
TMF_QUEUED,
TMF_SUCCESS,
TMF_FAILED,
TMF_TIMEDOUT,
TMF_NOT_FOUND,
};
/* Connection suspend "bit" */
#define ISCSI_SUSPEND_BIT 1
#define ISCSI_ITT_MASK 0x1fff
#define ISCSI_TOTAL_CMDS_MAX 4096
/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
#define ISCSI_TOTAL_CMDS_MIN 16
#define ISCSI_AGE_SHIFT 28
#define ISCSI_AGE_MASK 0xf
#define ISCSI_ADDRESS_BUF_LEN 64
enum {
/* this is the maximum possible storage for AHSs */
ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
sizeof(struct iscsi_rlength_ahdr),
ISCSI_DIGEST_SIZE = sizeof(__u32),
};
enum {
ISCSI_TASK_FREE,
ISCSI_TASK_COMPLETED,
ISCSI_TASK_PENDING,
ISCSI_TASK_RUNNING,
ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
};
struct iscsi_r2t_info {
__be32 ttt; /* copied from R2T */
__be32 exp_statsn; /* copied from R2T */
uint32_t data_length; /* copied from R2T */
uint32_t data_offset; /* copied from R2T */
int data_count; /* DATA-Out payload progress */
int datasn;
/* LLDs should set/update these values */
int sent; /* R2T sequence progress */
};
struct iscsi_task {
/*
* Because LLDs allocate their hdr differently, this is a pointer
* and length to that storage. It must be setup at session
* creation time.
*/
struct iscsi_hdr *hdr;
unsigned short hdr_max;
unsigned short hdr_len; /* accumulated size of hdr used */
/* copied values in case we need to send tmfs */
itt_t hdr_itt;
__be32 cmdsn;
uint8_t lun[8];
int itt; /* this ITT */
unsigned imm_count; /* imm-data (bytes) */
/* offset in unsolicited stream (bytes); */
struct iscsi_r2t_info unsol_r2t;
char *data; /* mgmt payload */
unsigned data_count;
struct scsi_cmnd *sc; /* associated SCSI cmd*/
struct iscsi_conn *conn; /* used connection */
/* data processing tracking */
unsigned long last_xfer;
unsigned long last_timeout;
bool have_checked_conn;
/* state set/tested under session->lock */
int state;
atomic_t refcount;
struct list_head running; /* running cmd list */
void *dd_data; /* driver/transport data */
};
static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
{
return task->unsol_r2t.data_length > task->unsol_r2t.sent;
}
static inline void* iscsi_next_hdr(struct iscsi_task *task)
{
return (void*)task->hdr + task->hdr_len;
}
/* Connection's states */
enum {
ISCSI_CONN_INITIAL_STAGE,
ISCSI_CONN_STARTED,
ISCSI_CONN_STOPPED,
ISCSI_CONN_CLEANUP_WAIT,
};
struct iscsi_conn {
struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
void *dd_data; /* iscsi_transport data */
struct iscsi_session *session; /* parent session */
/*
* conn_stop() flag: stop to recover, stop to terminate
*/
int stop_stage;
struct timer_list transport_timer;
unsigned long last_recv;
unsigned long last_ping;
int ping_timeout;
int recv_timeout;
struct iscsi_task *ping_task;
/* iSCSI connection-wide sequencing */
uint32_t exp_statsn;
/* control data */
int id; /* CID */
int c_stage; /* connection state */
/*
* Preallocated buffer for pdus that have data but do not
* originate from scsi-ml. We never have two pdus using the
* buffer at the same time. It is only allocated to
* the default max recv size because the pdus we support
* should always fit in this buffer
*/
char *data;
struct iscsi_task *login_task; /* mtask used for login/text */
struct iscsi_task *task; /* xmit task in progress */
/* xmit */
struct list_head mgmtqueue; /* mgmt (control) xmit queue */
struct list_head cmdqueue; /* data-path cmd queue */
struct list_head requeue; /* tasks needing another run */
struct work_struct xmitwork; /* per-conn. xmit workqueue */
unsigned long suspend_tx; /* suspend Tx */
unsigned long suspend_rx; /* suspend Rx */
/* abort */
wait_queue_head_t ehwait; /* used in eh_abort() */
struct iscsi_tm tmhdr;
struct timer_list tmf_timer;
int tmf_state; /* see TMF_INITIAL, etc.*/
/* negotiated params */
unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
unsigned max_xmit_dlength; /* target_max_recv_dsl */
int hdrdgst_en;
int datadgst_en;
int ifmarker_en;
int ofmarker_en;
/* values userspace uses to id a conn */
int persistent_port;
char *persistent_address;
/* remote portal currently connected to */
int portal_port;
char portal_address[ISCSI_ADDRESS_BUF_LEN];
/* MIB-statistics */
uint64_t txdata_octets;
uint64_t rxdata_octets;
uint32_t scsicmd_pdus_cnt;
uint32_t dataout_pdus_cnt;
uint32_t scsirsp_pdus_cnt;
uint32_t datain_pdus_cnt;
uint32_t r2t_pdus_cnt;
uint32_t tmfcmd_pdus_cnt;
int32_t tmfrsp_pdus_cnt;
/* custom statistics */
uint32_t eh_abort_cnt;
uint32_t fmr_unalign_cnt;
};
struct iscsi_pool {
struct kfifo *queue; /* FIFO Queue */
void **pool; /* Pool of elements */
int max; /* Max number of elements */
};
/* Session's states */
enum {
ISCSI_STATE_FREE = 1,
ISCSI_STATE_LOGGED_IN,
ISCSI_STATE_FAILED,
ISCSI_STATE_TERMINATE,
ISCSI_STATE_IN_RECOVERY,
ISCSI_STATE_RECOVERY_FAILED,
ISCSI_STATE_LOGGING_OUT,
};
struct iscsi_session {
struct iscsi_cls_session *cls_session;
/*
* Syncs up the scsi eh thread with the iscsi eh thread when sending
* task management functions. This must be taken before the session
* and recv lock.
*/
struct mutex eh_mutex;
/* iSCSI session-wide sequencing */
uint32_t cmdsn;
uint32_t exp_cmdsn;
uint32_t max_cmdsn;
/* This tracks the reqs queued into the initiator */
uint32_t queued_cmdsn;
/* configuration */
int abort_timeout;
int lu_reset_timeout;
int initial_r2t_en;
unsigned max_r2t;
int imm_data_en;
unsigned first_burst;
unsigned max_burst;
int time2wait;
int time2retain;
int pdu_inorder_en;
int dataseq_inorder_en;
int erl;
int fast_abort;
int tpgt;
char *username;
char *username_in;
char *password;
char *password_in;
char *targetname;
char *ifacename;
char *initiatorname;
/* control data */
struct iscsi_transport *tt;
struct Scsi_Host *host;
struct iscsi_conn *leadconn; /* leading connection */
spinlock_t lock; /* protects session state, *
* sequence numbers, *
* session resources: *
* - cmdpool, *
* - mgmtpool, *
* - r2tpool */
int state; /* session state */
int age; /* counts session re-opens */
int scsi_cmds_max; /* max scsi commands */
int cmds_max; /* size of cmds array */
struct iscsi_task **cmds; /* Original Cmds arr */
struct iscsi_pool cmdpool; /* PDU's pool */
void *dd_data; /* LLD private data */
};
enum {
ISCSI_HOST_SETUP,
ISCSI_HOST_REMOVED,
};
struct iscsi_host {
char *initiatorname;
/* hw address or netdev iscsi connection is bound to */
char *hwaddress;
char *netdev;
/* local address */
int local_port;
char local_address[ISCSI_ADDRESS_BUF_LEN];
wait_queue_head_t session_removal_wq;
/* protects sessions and state */
spinlock_t lock;
int num_sessions;
int state;
struct workqueue_struct *workq;
char workq_name[20];
};
/*
* scsi host template
*/
extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
extern int iscsi_eh_abort(struct scsi_cmnd *sc);
extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
extern int iscsi_queuecommand(struct scsi_cmnd *sc,
void (*done)(struct scsi_cmnd *));
/*
* iSCSI host helpers.
*/
#define iscsi_host_priv(_shost) \
(shost_priv(_shost) + sizeof(struct iscsi_host))
extern int iscsi_host_set_param(struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf,
int buflen);
extern int iscsi_host_get_param(struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf);
extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
int dd_data_size,
bool xmit_can_sleep);
extern void iscsi_host_remove(struct Scsi_Host *shost);
extern void iscsi_host_free(struct Scsi_Host *shost);
extern int iscsi_target_alloc(struct scsi_target *starget);
/*
* session management
*/
extern struct iscsi_cls_session *
iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
uint16_t, int, int, uint32_t, unsigned int);
extern void iscsi_session_teardown(struct iscsi_cls_session *);
extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf, int buflen);
extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
enum iscsi_param param, char *buf);
#define iscsi_session_printk(prefix, _sess, fmt, a...) \
iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
/*
* connection management
*/
extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
int, uint32_t);
extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
extern int iscsi_conn_start(struct iscsi_cls_conn *);
extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
int);
extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
extern void iscsi_session_failure(struct iscsi_session *session,
enum iscsi_err err);
extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf);
extern void iscsi_suspend_tx(struct iscsi_conn *conn);
extern void iscsi_suspend_queue(struct iscsi_conn *conn);
extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
#define iscsi_conn_printk(prefix, _c, fmt, a...) \
iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
fmt, ##a)
/*
* pdu and task processing
*/
extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
struct iscsi_r2t_info *r2t,
struct iscsi_data *hdr);
extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
char *, uint32_t);
extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
char *, int);
extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
char *, int);
extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
extern void iscsi_requeue_task(struct iscsi_task *task);
extern void iscsi_put_task(struct iscsi_task *task);
extern void __iscsi_get_task(struct iscsi_task *task);
extern void iscsi_complete_scsi_task(struct iscsi_task *task,
uint32_t exp_cmdsn, uint32_t max_cmdsn);
/*
* generic helpers
*/
extern void iscsi_pool_free(struct iscsi_pool *);
extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
/*
* inline functions to deal with padding.
*/
static inline unsigned int
iscsi_padded(unsigned int len)
{
return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
}
static inline unsigned int
iscsi_padding(unsigned int len)
{
len &= (ISCSI_PAD_LEN - 1);
if (len)
len = ISCSI_PAD_LEN - len;
return len;
}
#endif