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 <scsi/iscsi_proto.h>
32 #include <scsi/iscsi_if.h>
33 #include <scsi/scsi_transport_iscsi.h>
35 struct scsi_transport_template;
36 struct scsi_host_template;
42 struct iscsi_transport;
43 struct iscsi_cls_session;
44 struct iscsi_cls_conn;
49 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
50 #define ISCSI_MGMT_CMDS_MAX 15
52 #define ISCSI_DEF_CMD_PER_LUN 32
54 /* Task Mgmt states */
64 /* Connection suspend "bit" */
65 #define ISCSI_SUSPEND_BIT 1
67 #define ISCSI_ITT_MASK 0x1fff
68 #define ISCSI_TOTAL_CMDS_MAX 4096
69 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
70 #define ISCSI_TOTAL_CMDS_MIN 16
71 #define ISCSI_AGE_SHIFT 28
72 #define ISCSI_AGE_MASK 0xf
74 #define ISCSI_ADDRESS_BUF_LEN 64
77 /* this is the maximum possible storage for AHSs */
78 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
79 sizeof(struct iscsi_rlength_ahdr),
80 ISCSI_DIGEST_SIZE = sizeof(__u32),
91 struct iscsi_r2t_info {
92 __be32 ttt; /* copied from R2T */
93 __be32 exp_statsn; /* copied from R2T */
94 uint32_t data_length; /* copied from R2T */
95 uint32_t data_offset; /* copied from R2T */
96 int data_count; /* DATA-Out payload progress */
98 /* LLDs should set/update these values */
99 int sent; /* R2T sequence progress */
104 * Because LLDs allocate their hdr differently, this is a pointer
105 * and length to that storage. It must be setup at session
108 struct iscsi_hdr *hdr;
109 unsigned short hdr_max;
110 unsigned short hdr_len; /* accumulated size of hdr used */
111 /* copied values in case we need to send tmfs */
116 int itt; /* this ITT */
118 unsigned imm_count; /* imm-data (bytes) */
119 /* offset in unsolicited stream (bytes); */
120 struct iscsi_r2t_info unsol_r2t;
121 char *data; /* mgmt payload */
123 struct scsi_cmnd *sc; /* associated SCSI cmd*/
124 struct iscsi_conn *conn; /* used connection */
126 /* state set/tested under session->lock */
129 struct list_head running; /* running cmd list */
130 void *dd_data; /* driver/transport data */
133 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
135 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
138 static inline void* iscsi_next_hdr(struct iscsi_task *task)
140 return (void*)task->hdr + task->hdr_len;
143 /* Connection's states */
145 ISCSI_CONN_INITIAL_STAGE,
148 ISCSI_CONN_CLEANUP_WAIT,
152 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
153 void *dd_data; /* iscsi_transport data */
154 struct iscsi_session *session; /* parent session */
156 * conn_stop() flag: stop to recover, stop to terminate
159 struct timer_list transport_timer;
160 unsigned long last_recv;
161 unsigned long last_ping;
164 struct iscsi_task *ping_task;
166 /* iSCSI connection-wide sequencing */
171 int c_stage; /* connection state */
173 * Preallocated buffer for pdus that have data but do not
174 * originate from scsi-ml. We never have two pdus using the
175 * buffer at the same time. It is only allocated to
176 * the default max recv size because the pdus we support
177 * should always fit in this buffer
180 struct iscsi_task *login_task; /* mtask used for login/text */
181 struct iscsi_task *task; /* xmit task in progress */
184 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
185 struct list_head cmdqueue; /* data-path cmd queue */
186 struct list_head requeue; /* tasks needing another run */
187 struct work_struct xmitwork; /* per-conn. xmit workqueue */
188 unsigned long suspend_tx; /* suspend Tx */
189 unsigned long suspend_rx; /* suspend Rx */
192 wait_queue_head_t ehwait; /* used in eh_abort() */
193 struct iscsi_tm tmhdr;
194 struct timer_list tmf_timer;
195 int tmf_state; /* see TMF_INITIAL, etc.*/
197 /* negotiated params */
198 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
199 unsigned max_xmit_dlength; /* target_max_recv_dsl */
204 /* values userspace uses to id a conn */
206 char *persistent_address;
207 /* remote portal currently connected to */
209 char portal_address[ISCSI_ADDRESS_BUF_LEN];
212 uint64_t txdata_octets;
213 uint64_t rxdata_octets;
214 uint32_t scsicmd_pdus_cnt;
215 uint32_t dataout_pdus_cnt;
216 uint32_t scsirsp_pdus_cnt;
217 uint32_t datain_pdus_cnt;
218 uint32_t r2t_pdus_cnt;
219 uint32_t tmfcmd_pdus_cnt;
220 int32_t tmfrsp_pdus_cnt;
222 /* custom statistics */
223 uint32_t eh_abort_cnt;
224 uint32_t fmr_unalign_cnt;
228 struct kfifo *queue; /* FIFO Queue */
229 void **pool; /* Pool of elements */
230 int max; /* Max number of elements */
233 /* Session's states */
235 ISCSI_STATE_FREE = 1,
236 ISCSI_STATE_LOGGED_IN,
238 ISCSI_STATE_TERMINATE,
239 ISCSI_STATE_IN_RECOVERY,
240 ISCSI_STATE_RECOVERY_FAILED,
241 ISCSI_STATE_LOGGING_OUT,
244 struct iscsi_session {
245 struct iscsi_cls_session *cls_session;
247 * Syncs up the scsi eh thread with the iscsi eh thread when sending
248 * task management functions. This must be taken before the session
251 struct mutex eh_mutex;
253 /* iSCSI session-wide sequencing */
258 /* This tracks the reqs queued into the initiator */
259 uint32_t queued_cmdsn;
263 int lu_reset_timeout;
267 unsigned first_burst;
272 int dataseq_inorder_en;
284 struct iscsi_transport *tt;
285 struct Scsi_Host *host;
286 struct iscsi_conn *leadconn; /* leading connection */
287 spinlock_t lock; /* protects session state, *
288 * sequence numbers, *
289 * session resources: *
293 int state; /* session state */
294 int age; /* counts session re-opens */
296 int scsi_cmds_max; /* max scsi commands */
297 int cmds_max; /* size of cmds array */
298 struct iscsi_task **cmds; /* Original Cmds arr */
299 struct iscsi_pool cmdpool; /* PDU's pool */
309 /* hw address or netdev iscsi connection is bound to */
314 char local_address[ISCSI_ADDRESS_BUF_LEN];
316 wait_queue_head_t session_removal_wq;
317 /* protects sessions and state */
322 struct workqueue_struct *workq;
329 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
330 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
331 extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
332 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
333 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
334 void (*done)(struct scsi_cmnd *));
337 * iSCSI host helpers.
339 #define iscsi_host_priv(_shost) \
340 (shost_priv(_shost) + sizeof(struct iscsi_host))
342 extern int iscsi_host_set_param(struct Scsi_Host *shost,
343 enum iscsi_host_param param, char *buf,
345 extern int iscsi_host_get_param(struct Scsi_Host *shost,
346 enum iscsi_host_param param, char *buf);
347 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
348 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
350 bool xmit_can_sleep);
351 extern void iscsi_host_remove(struct Scsi_Host *shost);
352 extern void iscsi_host_free(struct Scsi_Host *shost);
353 extern int iscsi_target_alloc(struct scsi_target *starget);
358 extern struct iscsi_cls_session *
359 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
360 uint16_t, int, uint32_t, unsigned int);
361 extern void iscsi_session_teardown(struct iscsi_cls_session *);
362 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
363 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
364 enum iscsi_param param, char *buf, int buflen);
365 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
366 enum iscsi_param param, char *buf);
368 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
369 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
372 * connection management
374 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
376 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
377 extern int iscsi_conn_start(struct iscsi_cls_conn *);
378 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
379 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
381 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
382 extern void iscsi_session_failure(struct iscsi_session *session,
384 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
385 enum iscsi_param param, char *buf);
386 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
387 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
389 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
390 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
394 * pdu and task processing
396 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
397 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
398 struct iscsi_r2t_info *r2t,
399 struct iscsi_data *hdr);
400 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
402 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
404 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
406 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
407 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
408 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
409 extern void iscsi_requeue_task(struct iscsi_task *task);
410 extern void iscsi_put_task(struct iscsi_task *task);
411 extern void __iscsi_get_task(struct iscsi_task *task);
416 extern void iscsi_pool_free(struct iscsi_pool *);
417 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
420 * inline functions to deal with padding.
422 static inline unsigned int
423 iscsi_padded(unsigned int len)
425 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
428 static inline unsigned int
429 iscsi_padding(unsigned int len)
431 len &= (ISCSI_PAD_LEN - 1);
433 len = ISCSI_PAD_LEN - len;