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>
34 struct scsi_transport_template;
35 struct scsi_host_template;
40 struct iscsi_transport;
41 struct iscsi_cls_session;
42 struct iscsi_cls_conn;
47 /* #define DEBUG_SCSI */
49 #define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
51 #define debug_scsi(fmt...)
54 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
55 #define ISCSI_MGMT_CMDS_MAX 15
57 #define ISCSI_DEF_CMD_PER_LUN 32
58 #define ISCSI_MAX_CMD_PER_LUN 128
60 /* Task Mgmt states */
70 /* Connection suspend "bit" */
71 #define ISCSI_SUSPEND_BIT 1
73 #define ISCSI_ITT_MASK (0x1fff)
74 #define ISCSI_TOTAL_CMDS_MAX 4096
75 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
76 #define ISCSI_TOTAL_CMDS_MIN 16
77 #define ISCSI_AGE_SHIFT 28
78 #define ISCSI_AGE_MASK (0xf << ISCSI_AGE_SHIFT)
80 #define ISCSI_ADDRESS_BUF_LEN 64
83 /* this is the maximum possible storage for AHSs */
84 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
85 sizeof(struct iscsi_rlength_ahdr),
86 ISCSI_DIGEST_SIZE = sizeof(__u32),
96 struct iscsi_r2t_info {
97 __be32 ttt; /* copied from R2T */
98 __be32 exp_statsn; /* copied from R2T */
99 uint32_t data_length; /* copied from R2T */
100 uint32_t data_offset; /* copied from R2T */
101 int data_count; /* DATA-Out payload progress */
103 /* LLDs should set/update these values */
104 int sent; /* R2T sequence progress */
109 * Because LLDs allocate their hdr differently, this is a pointer
110 * and length to that storage. It must be setup at session
113 struct iscsi_hdr *hdr;
114 unsigned short hdr_max;
115 unsigned short hdr_len; /* accumulated size of hdr used */
116 /* copied values in case we need to send tmfs */
121 int itt; /* this ITT */
123 unsigned imm_count; /* imm-data (bytes) */
124 /* offset in unsolicited stream (bytes); */
125 struct iscsi_r2t_info unsol_r2t;
126 char *data; /* mgmt payload */
128 struct scsi_cmnd *sc; /* associated SCSI cmd*/
129 struct iscsi_conn *conn; /* used connection */
131 /* state set/tested under session->lock */
134 struct list_head running; /* running cmd list */
135 void *dd_data; /* driver/transport data */
138 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
140 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
143 static inline void* iscsi_next_hdr(struct iscsi_task *task)
145 return (void*)task->hdr + task->hdr_len;
148 /* Connection's states */
150 ISCSI_CONN_INITIAL_STAGE,
153 ISCSI_CONN_CLEANUP_WAIT,
157 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
158 void *dd_data; /* iscsi_transport data */
159 struct iscsi_session *session; /* parent session */
161 * conn_stop() flag: stop to recover, stop to terminate
164 struct timer_list transport_timer;
165 unsigned long last_recv;
166 unsigned long last_ping;
169 struct iscsi_task *ping_task;
171 /* iSCSI connection-wide sequencing */
176 int c_stage; /* connection state */
178 * Preallocated buffer for pdus that have data but do not
179 * originate from scsi-ml. We never have two pdus using the
180 * buffer at the same time. It is only allocated to
181 * the default max recv size because the pdus we support
182 * should always fit in this buffer
185 struct iscsi_task *login_task; /* mtask used for login/text */
186 struct iscsi_task *task; /* xmit task in progress */
189 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
190 struct list_head mgmt_run_list; /* list of control tasks */
191 struct list_head xmitqueue; /* data-path cmd queue */
192 struct list_head run_list; /* list of cmds in progress */
193 struct list_head requeue; /* tasks needing another run */
194 struct work_struct xmitwork; /* per-conn. xmit workqueue */
195 unsigned long suspend_tx; /* suspend Tx */
196 unsigned long suspend_rx; /* suspend Rx */
199 wait_queue_head_t ehwait; /* used in eh_abort() */
200 struct iscsi_tm tmhdr;
201 struct timer_list tmf_timer;
202 int tmf_state; /* see TMF_INITIAL, etc.*/
204 /* negotiated params */
205 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
206 unsigned max_xmit_dlength; /* target_max_recv_dsl */
211 /* values userspace uses to id a conn */
213 char *persistent_address;
214 /* remote portal currently connected to */
216 char portal_address[ISCSI_ADDRESS_BUF_LEN];
219 uint64_t txdata_octets;
220 uint64_t rxdata_octets;
221 uint32_t scsicmd_pdus_cnt;
222 uint32_t dataout_pdus_cnt;
223 uint32_t scsirsp_pdus_cnt;
224 uint32_t datain_pdus_cnt;
225 uint32_t r2t_pdus_cnt;
226 uint32_t tmfcmd_pdus_cnt;
227 int32_t tmfrsp_pdus_cnt;
229 /* custom statistics */
230 uint32_t eh_abort_cnt;
231 uint32_t fmr_unalign_cnt;
235 struct kfifo *queue; /* FIFO Queue */
236 void **pool; /* Pool of elements */
237 int max; /* Max number of elements */
240 /* Session's states */
242 ISCSI_STATE_FREE = 1,
243 ISCSI_STATE_LOGGED_IN,
245 ISCSI_STATE_TERMINATE,
246 ISCSI_STATE_IN_RECOVERY,
247 ISCSI_STATE_RECOVERY_FAILED,
248 ISCSI_STATE_LOGGING_OUT,
251 struct iscsi_session {
252 struct iscsi_cls_session *cls_session;
254 * Syncs up the scsi eh thread with the iscsi eh thread when sending
255 * task management functions. This must be taken before the session
258 struct mutex eh_mutex;
260 /* iSCSI session-wide sequencing */
265 /* This tracks the reqs queued into the initiator */
266 uint32_t queued_cmdsn;
270 int lu_reset_timeout;
274 unsigned first_burst;
279 int dataseq_inorder_en;
291 struct iscsi_transport *tt;
292 struct Scsi_Host *host;
293 struct iscsi_conn *leadconn; /* leading connection */
294 spinlock_t lock; /* protects session state, *
295 * sequence numbers, *
296 * session resources: *
300 int state; /* session state */
301 int age; /* counts session re-opens */
303 int scsi_cmds_max; /* max scsi commands */
304 int cmds_max; /* size of cmds array */
305 struct iscsi_task **cmds; /* Original Cmds arr */
306 struct iscsi_pool cmdpool; /* PDU's pool */
316 /* hw address or netdev iscsi connection is bound to */
321 char local_address[ISCSI_ADDRESS_BUF_LEN];
323 wait_queue_head_t session_removal_wq;
324 /* protects sessions and state */
333 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
334 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
335 extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
336 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
337 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
338 void (*done)(struct scsi_cmnd *));
341 * iSCSI host helpers.
343 #define iscsi_host_priv(_shost) \
344 (shost_priv(_shost) + sizeof(struct iscsi_host))
346 extern int iscsi_host_set_param(struct Scsi_Host *shost,
347 enum iscsi_host_param param, char *buf,
349 extern int iscsi_host_get_param(struct Scsi_Host *shost,
350 enum iscsi_host_param param, char *buf);
351 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
352 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
353 int dd_data_size, uint16_t qdepth);
354 extern void iscsi_host_remove(struct Scsi_Host *shost);
355 extern void iscsi_host_free(struct Scsi_Host *shost);
360 extern struct iscsi_cls_session *
361 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
362 uint16_t, int, uint32_t, unsigned int);
363 extern void iscsi_session_teardown(struct iscsi_cls_session *);
364 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
365 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
366 enum iscsi_param param, char *buf, int buflen);
367 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
368 enum iscsi_param param, char *buf);
370 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
371 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
374 * connection management
376 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
378 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
379 extern int iscsi_conn_start(struct iscsi_cls_conn *);
380 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
381 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
383 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
384 extern void iscsi_session_failure(struct iscsi_cls_session *cls_session,
386 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
387 enum iscsi_param param, char *buf);
388 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
390 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
391 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
395 * pdu and task processing
397 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
398 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
399 struct iscsi_r2t_info *r2t,
400 struct iscsi_data *hdr);
401 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
403 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
405 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
407 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
408 extern struct iscsi_task *iscsi_itt_to_ctask(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;