2 * iSCSI lib definitions
4 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2004 - 2006 Mike Christie
6 * Copyright (C) 2004 - 2005 Dmitry Yusupov
7 * Copyright (C) 2004 - 2005 Alex Aizman
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 #include <linux/types.h>
27 #include <linux/wait.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/workqueue.h>
31 #include <linux/kfifo.h>
32 #include <scsi/iscsi_proto.h>
33 #include <scsi/iscsi_if.h>
34 #include <scsi/scsi_transport_iscsi.h>
36 struct scsi_transport_template;
37 struct scsi_host_template;
43 struct iscsi_transport;
44 struct iscsi_cls_session;
45 struct iscsi_cls_conn;
50 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
51 #define ISCSI_MGMT_CMDS_MAX 15
53 #define ISCSI_DEF_CMD_PER_LUN 32
55 /* Task Mgmt states */
67 /* Connection suspend "bit" */
68 #define ISCSI_SUSPEND_BIT 1
70 #define ISCSI_ITT_MASK 0x1fff
71 #define ISCSI_TOTAL_CMDS_MAX 4096
72 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
73 #define ISCSI_TOTAL_CMDS_MIN 16
74 #define ISCSI_AGE_SHIFT 28
75 #define ISCSI_AGE_MASK 0xf
77 #define ISCSI_ADDRESS_BUF_LEN 64
80 /* this is the maximum possible storage for AHSs */
81 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
82 sizeof(struct iscsi_rlength_ahdr),
83 ISCSI_DIGEST_SIZE = sizeof(__u32),
92 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
93 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
94 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
97 struct iscsi_r2t_info {
98 __be32 ttt; /* copied from R2T */
99 __be32 exp_statsn; /* copied from R2T */
100 uint32_t data_length; /* copied from R2T */
101 uint32_t data_offset; /* copied from R2T */
102 int data_count; /* DATA-Out payload progress */
104 /* LLDs should set/update these values */
105 int sent; /* R2T sequence progress */
110 * Because LLDs allocate their hdr differently, this is a pointer
111 * and length to that storage. It must be setup at session
114 struct iscsi_hdr *hdr;
115 unsigned short hdr_max;
116 unsigned short hdr_len; /* accumulated size of hdr used */
117 /* copied values in case we need to send tmfs */
122 int itt; /* this ITT */
124 unsigned imm_count; /* imm-data (bytes) */
125 /* offset in unsolicited stream (bytes); */
126 struct iscsi_r2t_info unsol_r2t;
127 char *data; /* mgmt payload */
129 struct scsi_cmnd *sc; /* associated SCSI cmd*/
130 struct iscsi_conn *conn; /* used connection */
132 /* data processing tracking */
133 unsigned long last_xfer;
134 unsigned long last_timeout;
135 bool have_checked_conn;
137 /* T10 protection information */
140 /* state set/tested under session->lock */
143 struct list_head running; /* running cmd list */
144 void *dd_data; /* driver/transport data */
147 /* invalid scsi_task pointer */
148 #define INVALID_SCSI_TASK (struct iscsi_task *)-1l
150 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
152 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
155 static inline void* iscsi_next_hdr(struct iscsi_task *task)
157 return (void*)task->hdr + task->hdr_len;
160 /* Connection's states */
162 ISCSI_CONN_INITIAL_STAGE,
165 ISCSI_CONN_CLEANUP_WAIT,
169 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
170 void *dd_data; /* iscsi_transport data */
171 struct iscsi_session *session; /* parent session */
173 * conn_stop() flag: stop to recover, stop to terminate
176 struct timer_list transport_timer;
177 unsigned long last_recv;
178 unsigned long last_ping;
181 struct iscsi_task *ping_task;
183 /* iSCSI connection-wide sequencing */
189 int c_stage; /* connection state */
191 * Preallocated buffer for pdus that have data but do not
192 * originate from scsi-ml. We never have two pdus using the
193 * buffer at the same time. It is only allocated to
194 * the default max recv size because the pdus we support
195 * should always fit in this buffer
198 struct iscsi_task *login_task; /* mtask used for login/text */
199 struct iscsi_task *task; /* xmit task in progress */
202 spinlock_t taskqueuelock; /* protects the next three lists */
203 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
204 struct list_head cmdqueue; /* data-path cmd queue */
205 struct list_head requeue; /* tasks needing another run */
206 struct work_struct xmitwork; /* per-conn. xmit workqueue */
207 unsigned long suspend_tx; /* suspend Tx */
208 unsigned long suspend_rx; /* suspend Rx */
211 wait_queue_head_t ehwait; /* used in eh_abort() */
212 struct iscsi_tm tmhdr;
213 struct timer_list tmf_timer;
214 int tmf_state; /* see TMF_INITIAL, etc.*/
216 /* negotiated params */
217 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
218 unsigned max_xmit_dlength; /* target_max_recv_dsl */
223 /* values userspace uses to id a conn */
225 char *persistent_address;
227 unsigned max_segment_size;
228 unsigned tcp_xmit_wsf;
229 unsigned tcp_recv_wsf;
230 uint16_t keepalive_tmo;
232 uint8_t tcp_timestamp_stat;
233 uint8_t tcp_nagle_disable;
234 uint8_t tcp_wsf_disable;
235 uint8_t tcp_timer_scale;
236 uint8_t tcp_timestamp_en;
237 uint8_t fragment_disable;
239 uint8_t ipv6_traffic_class;
240 uint8_t ipv6_flow_label;
241 uint8_t is_fw_assigned_ipv6;
245 uint64_t txdata_octets;
246 uint64_t rxdata_octets;
247 uint32_t scsicmd_pdus_cnt;
248 uint32_t dataout_pdus_cnt;
249 uint32_t scsirsp_pdus_cnt;
250 uint32_t datain_pdus_cnt;
251 uint32_t r2t_pdus_cnt;
252 uint32_t tmfcmd_pdus_cnt;
253 int32_t tmfrsp_pdus_cnt;
255 /* custom statistics */
256 uint32_t eh_abort_cnt;
257 uint32_t fmr_unalign_cnt;
261 struct kfifo queue; /* FIFO Queue */
262 void **pool; /* Pool of elements */
263 int max; /* Max number of elements */
266 /* Session's states */
268 ISCSI_STATE_FREE = 1,
269 ISCSI_STATE_LOGGED_IN,
271 ISCSI_STATE_TERMINATE,
272 ISCSI_STATE_IN_RECOVERY,
273 ISCSI_STATE_RECOVERY_FAILED,
274 ISCSI_STATE_LOGGING_OUT,
277 struct iscsi_session {
278 struct iscsi_cls_session *cls_session;
280 * Syncs up the scsi eh thread with the iscsi eh thread when sending
281 * task management functions. This must be taken before the session
284 struct mutex eh_mutex;
286 /* iSCSI session-wide sequencing */
291 /* This tracks the reqs queued into the initiator */
292 uint32_t queued_cmdsn;
296 int lu_reset_timeout;
297 int tgt_reset_timeout;
299 unsigned short max_r2t;
301 unsigned first_burst;
306 int dataseq_inorder_en;
322 char *discovery_parent_type;
323 uint16_t discovery_parent_idx;
324 uint16_t def_taskmgmt_tmo;
326 uint8_t auto_snd_tgt_disable;
327 uint8_t discovery_sess;
328 uint8_t chap_auth_en;
329 uint8_t discovery_logout_en;
330 uint8_t bidi_chap_en;
331 uint8_t discovery_auth_optional;
332 uint8_t isid[ISID_SIZE];
335 struct iscsi_transport *tt;
336 struct Scsi_Host *host;
337 struct iscsi_conn *leadconn; /* leading connection */
338 /* Between the forward and the backward locks exists a strict locking
339 * hierarchy. The mutual exclusion zone protected by the forward lock
340 * can enclose the mutual exclusion zone protected by the backward lock
341 * but not vice versa.
343 spinlock_t frwd_lock; /* protects session state, *
344 * cmdsn, queued_cmdsn *
345 * session resources: *
346 * - cmdpool kfifo_out , *
348 spinlock_t back_lock; /* protects cmdsn_exp *
350 * cmdpool kfifo_in */
351 int state; /* session state */
352 int age; /* counts session re-opens */
354 int scsi_cmds_max; /* max scsi commands */
355 int cmds_max; /* size of cmds array */
356 struct iscsi_task **cmds; /* Original Cmds arr */
357 struct iscsi_pool cmdpool; /* PDU's pool */
358 void *dd_data; /* LLD private data */
368 /* hw address or netdev iscsi connection is bound to */
372 wait_queue_head_t session_removal_wq;
373 /* protects sessions and state */
378 struct workqueue_struct *workq;
385 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
386 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
387 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
388 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
389 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
392 * iSCSI host helpers.
394 #define iscsi_host_priv(_shost) \
395 (shost_priv(_shost) + sizeof(struct iscsi_host))
397 extern int iscsi_host_set_param(struct Scsi_Host *shost,
398 enum iscsi_host_param param, char *buf,
400 extern int iscsi_host_get_param(struct Scsi_Host *shost,
401 enum iscsi_host_param param, char *buf);
402 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
403 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
405 bool xmit_can_sleep);
406 extern void iscsi_host_remove(struct Scsi_Host *shost);
407 extern void iscsi_host_free(struct Scsi_Host *shost);
408 extern int iscsi_target_alloc(struct scsi_target *starget);
413 extern struct iscsi_cls_session *
414 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
415 uint16_t, int, int, uint32_t, unsigned int);
416 extern void iscsi_session_teardown(struct iscsi_cls_session *);
417 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
418 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
419 enum iscsi_param param, char *buf, int buflen);
420 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
421 enum iscsi_param param, char *buf);
423 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
424 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
427 * connection management
429 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
431 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
432 extern int iscsi_conn_start(struct iscsi_cls_conn *);
433 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
434 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
436 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
437 extern void iscsi_session_failure(struct iscsi_session *session,
439 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
440 enum iscsi_param param, char *buf);
441 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
442 enum iscsi_param param, char *buf);
443 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
444 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
445 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
447 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
448 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
452 * pdu and task processing
454 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
455 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
456 struct iscsi_r2t_info *r2t,
457 struct iscsi_data *hdr);
458 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
460 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
462 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
464 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
465 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
466 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
467 extern void iscsi_requeue_task(struct iscsi_task *task);
468 extern void iscsi_put_task(struct iscsi_task *task);
469 extern void __iscsi_put_task(struct iscsi_task *task);
470 extern void __iscsi_get_task(struct iscsi_task *task);
471 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
472 uint32_t exp_cmdsn, uint32_t max_cmdsn);
477 extern void iscsi_pool_free(struct iscsi_pool *);
478 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
479 extern int iscsi_switch_str_param(char **, char *);
482 * inline functions to deal with padding.
484 static inline unsigned int
485 iscsi_padded(unsigned int len)
487 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
490 static inline unsigned int
491 iscsi_padding(unsigned int len)
493 len &= (ISCSI_PAD_LEN - 1);
495 len = ISCSI_PAD_LEN - len;