]> Pileus Git - ~andy/linux/blob - drivers/scsi/libiscsi.c
[SCSI] libiscsi: fix setting of nop timer
[~andy/linux] / drivers / scsi / libiscsi.c
1 /*
2  * iSCSI lib functions
3  *
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
8  * maintained by open-iscsi@googlegroups.com
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  */
24 #include <linux/types.h>
25 #include <linux/kfifo.h>
26 #include <linux/delay.h>
27 #include <linux/log2.h>
28 #include <asm/unaligned.h>
29 #include <net/tcp.h>
30 #include <scsi/scsi_cmnd.h>
31 #include <scsi/scsi_device.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_tcq.h>
34 #include <scsi/scsi_host.h>
35 #include <scsi/scsi.h>
36 #include <scsi/iscsi_proto.h>
37 #include <scsi/scsi_transport.h>
38 #include <scsi/scsi_transport_iscsi.h>
39 #include <scsi/libiscsi.h>
40
41 struct iscsi_session *
42 class_to_transport_session(struct iscsi_cls_session *cls_session)
43 {
44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
45         return iscsi_hostdata(shost->hostdata);
46 }
47 EXPORT_SYMBOL_GPL(class_to_transport_session);
48
49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
50 #define SNA32_CHECK 2147483648UL
51
52 static int iscsi_sna_lt(u32 n1, u32 n2)
53 {
54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
56 }
57
58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
59 static int iscsi_sna_lte(u32 n1, u32 n2)
60 {
61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
63 }
64
65 void
66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
67 {
68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
70
71         /*
72          * standard specifies this check for when to update expected and
73          * max sequence numbers
74          */
75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
76                 return;
77
78         if (exp_cmdsn != session->exp_cmdsn &&
79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
80                 session->exp_cmdsn = exp_cmdsn;
81
82         if (max_cmdsn != session->max_cmdsn &&
83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
84                 session->max_cmdsn = max_cmdsn;
85                 /*
86                  * if the window closed with IO queued, then kick the
87                  * xmit thread
88                  */
89                 if (!list_empty(&session->leadconn->xmitqueue) ||
90                     !list_empty(&session->leadconn->mgmtqueue))
91                         scsi_queue_work(session->host,
92                                         &session->leadconn->xmitwork);
93         }
94 }
95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
96
97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
98                                    struct iscsi_data *hdr)
99 {
100         struct iscsi_conn *conn = ctask->conn;
101
102         memset(hdr, 0, sizeof(struct iscsi_data));
103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
105         ctask->unsol_datasn++;
106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
108
109         hdr->itt = ctask->hdr->itt;
110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
112
113         if (ctask->unsol_count > conn->max_xmit_dlength) {
114                 hton24(hdr->dlength, conn->max_xmit_dlength);
115                 ctask->data_count = conn->max_xmit_dlength;
116                 ctask->unsol_offset += ctask->data_count;
117                 hdr->flags = 0;
118         } else {
119                 hton24(hdr->dlength, ctask->unsol_count);
120                 ctask->data_count = ctask->unsol_count;
121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
122         }
123 }
124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
125
126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
127 {
128         unsigned exp_len = ctask->hdr_len + len;
129
130         if (exp_len > ctask->hdr_max) {
131                 WARN_ON(1);
132                 return -EINVAL;
133         }
134
135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
136         ctask->hdr_len = exp_len;
137         return 0;
138 }
139
140 /**
141  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
142  * @ctask: iscsi cmd task
143  *
144  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
145  * fields like dlength or final based on how much data it sends
146  */
147 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
148 {
149         struct iscsi_conn *conn = ctask->conn;
150         struct iscsi_session *session = conn->session;
151         struct iscsi_cmd *hdr = ctask->hdr;
152         struct scsi_cmnd *sc = ctask->sc;
153         unsigned hdrlength;
154         int rc;
155
156         ctask->hdr_len = 0;
157         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
158         if (rc)
159                 return rc;
160         hdr->opcode = ISCSI_OP_SCSI_CMD;
161         hdr->flags = ISCSI_ATTR_SIMPLE;
162         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
163         hdr->itt = build_itt(ctask->itt, conn->id, session->age);
164         hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
165         hdr->cmdsn = cpu_to_be32(session->cmdsn);
166         session->cmdsn++;
167         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
168         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
169         if (sc->cmd_len < MAX_COMMAND_SIZE)
170                 memset(&hdr->cdb[sc->cmd_len], 0,
171                         MAX_COMMAND_SIZE - sc->cmd_len);
172
173         ctask->imm_count = 0;
174         if (sc->sc_data_direction == DMA_TO_DEVICE) {
175                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
176                 /*
177                  * Write counters:
178                  *
179                  *      imm_count       bytes to be sent right after
180                  *                      SCSI PDU Header
181                  *
182                  *      unsol_count     bytes(as Data-Out) to be sent
183                  *                      without R2T ack right after
184                  *                      immediate data
185                  *
186                  *      r2t_data_count  bytes to be sent via R2T ack's
187                  *
188                  *      pad_count       bytes to be sent as zero-padding
189                  */
190                 ctask->unsol_count = 0;
191                 ctask->unsol_offset = 0;
192                 ctask->unsol_datasn = 0;
193
194                 if (session->imm_data_en) {
195                         if (scsi_bufflen(sc) >= session->first_burst)
196                                 ctask->imm_count = min(session->first_burst,
197                                                         conn->max_xmit_dlength);
198                         else
199                                 ctask->imm_count = min(scsi_bufflen(sc),
200                                                         conn->max_xmit_dlength);
201                         hton24(hdr->dlength, ctask->imm_count);
202                 } else
203                         zero_data(hdr->dlength);
204
205                 if (!session->initial_r2t_en) {
206                         ctask->unsol_count = min((session->first_burst),
207                                 (scsi_bufflen(sc))) - ctask->imm_count;
208                         ctask->unsol_offset = ctask->imm_count;
209                 }
210
211                 if (!ctask->unsol_count)
212                         /* No unsolicit Data-Out's */
213                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
214         } else {
215                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
216                 zero_data(hdr->dlength);
217
218                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
219                         hdr->flags |= ISCSI_FLAG_CMD_READ;
220         }
221
222         /* calculate size of additional header segments (AHSs) */
223         hdrlength = ctask->hdr_len - sizeof(*hdr);
224
225         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
226         hdrlength /= ISCSI_PAD_LEN;
227
228         WARN_ON(hdrlength >= 256);
229         hdr->hlength = hdrlength & 0xFF;
230
231         if (conn->session->tt->init_cmd_task(conn->ctask))
232                 return EIO;
233
234         conn->scsicmd_pdus_cnt++;
235         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
236                 "cmdsn %d win %d]\n",
237                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
238                 conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
239                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
240         return 0;
241 }
242
243 /**
244  * iscsi_complete_command - return command back to scsi-ml
245  * @ctask: iscsi cmd task
246  *
247  * Must be called with session lock.
248  * This function returns the scsi command to scsi-ml and returns
249  * the cmd task to the pool of available cmd tasks.
250  */
251 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
252 {
253         struct iscsi_conn *conn = ctask->conn;
254         struct iscsi_session *session = conn->session;
255         struct scsi_cmnd *sc = ctask->sc;
256
257         ctask->state = ISCSI_TASK_COMPLETED;
258         ctask->sc = NULL;
259         /* SCSI eh reuses commands to verify us */
260         sc->SCp.ptr = NULL;
261         if (conn->ctask == ctask)
262                 conn->ctask = NULL;
263         list_del_init(&ctask->running);
264         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
265         sc->scsi_done(sc);
266 }
267
268 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
269 {
270         atomic_inc(&ctask->refcount);
271 }
272
273 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
274 {
275         if (atomic_dec_and_test(&ctask->refcount))
276                 iscsi_complete_command(ctask);
277 }
278
279 /*
280  * session lock must be held
281  */
282 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
283                          int err)
284 {
285         struct scsi_cmnd *sc;
286
287         sc = ctask->sc;
288         if (!sc)
289                 return;
290
291         if (ctask->state == ISCSI_TASK_PENDING)
292                 /*
293                  * cmd never made it to the xmit thread, so we should not count
294                  * the cmd in the sequencing
295                  */
296                 conn->session->queued_cmdsn--;
297         else
298                 conn->session->tt->cleanup_cmd_task(conn, ctask);
299
300         sc->result = err;
301         scsi_set_resid(sc, scsi_bufflen(sc));
302         if (conn->ctask == ctask)
303                 conn->ctask = NULL;
304         /* release ref from queuecommand */
305         __iscsi_put_ctask(ctask);
306 }
307
308 /**
309  * iscsi_free_mgmt_task - return mgmt task back to pool
310  * @conn: iscsi connection
311  * @mtask: mtask
312  *
313  * Must be called with session lock.
314  */
315 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
316                           struct iscsi_mgmt_task *mtask)
317 {
318         list_del_init(&mtask->running);
319         if (conn->login_mtask == mtask)
320                 return;
321
322         if (conn->ping_mtask == mtask)
323                 conn->ping_mtask = NULL;
324         __kfifo_put(conn->session->mgmtpool.queue,
325                     (void*)&mtask, sizeof(void*));
326 }
327 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
328
329 static struct iscsi_mgmt_task *
330 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
331                       char *data, uint32_t data_size)
332 {
333         struct iscsi_session *session = conn->session;
334         struct iscsi_mgmt_task *mtask;
335
336         if (session->state == ISCSI_STATE_TERMINATE)
337                 return NULL;
338
339         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
340             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
341                 /*
342                  * Login and Text are sent serially, in
343                  * request-followed-by-response sequence.
344                  * Same mtask can be used. Same ITT must be used.
345                  * Note that login_mtask is preallocated at conn_create().
346                  */
347                 mtask = conn->login_mtask;
348         else {
349                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
350                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
351
352                 if (!__kfifo_get(session->mgmtpool.queue,
353                                  (void*)&mtask, sizeof(void*)))
354                         return NULL;
355         }
356
357         if (data_size) {
358                 memcpy(mtask->data, data, data_size);
359                 mtask->data_count = data_size;
360         } else
361                 mtask->data_count = 0;
362
363         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
364         INIT_LIST_HEAD(&mtask->running);
365         list_add_tail(&mtask->running, &conn->mgmtqueue);
366         return mtask;
367 }
368
369 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
370                         char *data, uint32_t data_size)
371 {
372         struct iscsi_conn *conn = cls_conn->dd_data;
373         struct iscsi_session *session = conn->session;
374         int err = 0;
375
376         spin_lock_bh(&session->lock);
377         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
378                 err = -EPERM;
379         spin_unlock_bh(&session->lock);
380         scsi_queue_work(session->host, &conn->xmitwork);
381         return err;
382 }
383 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
384
385 /**
386  * iscsi_cmd_rsp - SCSI Command Response processing
387  * @conn: iscsi connection
388  * @hdr: iscsi header
389  * @ctask: scsi command task
390  * @data: cmd data buffer
391  * @datalen: len of buffer
392  *
393  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
394  * then completes the command and task.
395  **/
396 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
397                                struct iscsi_cmd_task *ctask, char *data,
398                                int datalen)
399 {
400         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
401         struct iscsi_session *session = conn->session;
402         struct scsi_cmnd *sc = ctask->sc;
403
404         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
405         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
406
407         sc->result = (DID_OK << 16) | rhdr->cmd_status;
408
409         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
410                 sc->result = DID_ERROR << 16;
411                 goto out;
412         }
413
414         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
415                 uint16_t senselen;
416
417                 if (datalen < 2) {
418 invalid_datalen:
419                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
420                                "invalid data buffer size of %d\n", datalen);
421                         sc->result = DID_BAD_TARGET << 16;
422                         goto out;
423                 }
424
425                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
426                 if (datalen < senselen)
427                         goto invalid_datalen;
428
429                 memcpy(sc->sense_buffer, data + 2,
430                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
431                 debug_scsi("copied %d bytes of sense\n",
432                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
433         }
434
435         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
436                            ISCSI_FLAG_CMD_OVERFLOW)) {
437                 int res_count = be32_to_cpu(rhdr->residual_count);
438
439                 if (res_count > 0 &&
440                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
441                      res_count <= scsi_bufflen(sc)))
442                         scsi_set_resid(sc, res_count);
443                 else
444                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
445         } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
446                                   ISCSI_FLAG_CMD_BIDI_OVERFLOW))
447                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
448
449 out:
450         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
451                    (long)sc, sc->result, ctask->itt);
452         conn->scsirsp_pdus_cnt++;
453
454         __iscsi_put_ctask(ctask);
455 }
456
457 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
458 {
459         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
460
461         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
462         conn->tmfrsp_pdus_cnt++;
463
464         if (conn->tmf_state != TMF_QUEUED)
465                 return;
466
467         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
468                 conn->tmf_state = TMF_SUCCESS;
469         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
470                 conn->tmf_state = TMF_NOT_FOUND;
471         else
472                 conn->tmf_state = TMF_FAILED;
473         wake_up(&conn->ehwait);
474 }
475
476 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
477 {
478         struct iscsi_nopout hdr;
479         struct iscsi_mgmt_task *mtask;
480
481         if (!rhdr && conn->ping_mtask)
482                 return;
483
484         memset(&hdr, 0, sizeof(struct iscsi_nopout));
485         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
486         hdr.flags = ISCSI_FLAG_CMD_FINAL;
487
488         if (rhdr) {
489                 memcpy(hdr.lun, rhdr->lun, 8);
490                 hdr.ttt = rhdr->ttt;
491                 hdr.itt = RESERVED_ITT;
492         } else
493                 hdr.ttt = RESERVED_ITT;
494
495         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
496         if (!mtask) {
497                 printk(KERN_ERR "Could not send nopout\n");
498                 return;
499         }
500
501         /* only track our nops */
502         if (!rhdr) {
503                 conn->ping_mtask = mtask;
504                 conn->last_ping = jiffies;
505         }
506         scsi_queue_work(conn->session->host, &conn->xmitwork);
507 }
508
509 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
510                                char *data, int datalen)
511 {
512         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
513         struct iscsi_hdr rejected_pdu;
514         uint32_t itt;
515
516         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
517
518         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
519                 if (ntoh24(reject->dlength) > datalen)
520                         return ISCSI_ERR_PROTO;
521
522                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
523                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
524                         itt = get_itt(rejected_pdu.itt);
525                         printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
526                                 "due to DataDigest error.\n", itt,
527                                 rejected_pdu.opcode);
528                 }
529         }
530         return 0;
531 }
532
533 /**
534  * __iscsi_complete_pdu - complete pdu
535  * @conn: iscsi conn
536  * @hdr: iscsi header
537  * @data: data buffer
538  * @datalen: len of data buffer
539  *
540  * Completes pdu processing by freeing any resources allocated at
541  * queuecommand or send generic. session lock must be held and verify
542  * itt must have been called.
543  */
544 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
545                                 char *data, int datalen)
546 {
547         struct iscsi_session *session = conn->session;
548         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
549         struct iscsi_cmd_task *ctask;
550         struct iscsi_mgmt_task *mtask;
551         uint32_t itt;
552
553         conn->last_recv = jiffies;
554         if (hdr->itt != RESERVED_ITT)
555                 itt = get_itt(hdr->itt);
556         else
557                 itt = ~0U;
558
559         if (itt < session->cmds_max) {
560                 ctask = session->cmds[itt];
561
562                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
563                            opcode, conn->id, ctask->itt, datalen);
564
565                 switch(opcode) {
566                 case ISCSI_OP_SCSI_CMD_RSP:
567                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
568                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
569                                            datalen);
570                         break;
571                 case ISCSI_OP_SCSI_DATA_IN:
572                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
573                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
574                                 conn->scsirsp_pdus_cnt++;
575                                 __iscsi_put_ctask(ctask);
576                         }
577                         break;
578                 case ISCSI_OP_R2T:
579                         /* LLD handles this for now */
580                         break;
581                 default:
582                         rc = ISCSI_ERR_BAD_OPCODE;
583                         break;
584                 }
585         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
586                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
587                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
588
589                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
590                            opcode, conn->id, mtask->itt, datalen);
591
592                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
593                 switch(opcode) {
594                 case ISCSI_OP_LOGOUT_RSP:
595                         if (datalen) {
596                                 rc = ISCSI_ERR_PROTO;
597                                 break;
598                         }
599                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
600                         /* fall through */
601                 case ISCSI_OP_LOGIN_RSP:
602                 case ISCSI_OP_TEXT_RSP:
603                         /*
604                          * login related PDU's exp_statsn is handled in
605                          * userspace
606                          */
607                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
608                                 rc = ISCSI_ERR_CONN_FAILED;
609                         iscsi_free_mgmt_task(conn, mtask);
610                         break;
611                 case ISCSI_OP_SCSI_TMFUNC_RSP:
612                         if (datalen) {
613                                 rc = ISCSI_ERR_PROTO;
614                                 break;
615                         }
616
617                         iscsi_tmf_rsp(conn, hdr);
618                         iscsi_free_mgmt_task(conn, mtask);
619                         break;
620                 case ISCSI_OP_NOOP_IN:
621                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
622                             datalen) {
623                                 rc = ISCSI_ERR_PROTO;
624                                 break;
625                         }
626                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
627
628                         if (conn->ping_mtask != mtask) {
629                                 /*
630                                  * If this is not in response to one of our
631                                  * nops then it must be from userspace.
632                                  */
633                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
634                                                    datalen))
635                                         rc = ISCSI_ERR_CONN_FAILED;
636                         }
637                         iscsi_free_mgmt_task(conn, mtask);
638                         break;
639                 default:
640                         rc = ISCSI_ERR_BAD_OPCODE;
641                         break;
642                 }
643         } else if (itt == ~0U) {
644                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
645
646                 switch(opcode) {
647                 case ISCSI_OP_NOOP_IN:
648                         if (datalen) {
649                                 rc = ISCSI_ERR_PROTO;
650                                 break;
651                         }
652
653                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
654                                 break;
655
656                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
657                         break;
658                 case ISCSI_OP_REJECT:
659                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
660                         break;
661                 case ISCSI_OP_ASYNC_EVENT:
662                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
663                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
664                                 rc = ISCSI_ERR_CONN_FAILED;
665                         break;
666                 default:
667                         rc = ISCSI_ERR_BAD_OPCODE;
668                         break;
669                 }
670         } else
671                 rc = ISCSI_ERR_BAD_ITT;
672
673         return rc;
674 }
675
676 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
677                        char *data, int datalen)
678 {
679         int rc;
680
681         spin_lock(&conn->session->lock);
682         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
683         spin_unlock(&conn->session->lock);
684         return rc;
685 }
686 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
687
688 /* verify itt (itt encoding: age+cid+itt) */
689 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
690                      uint32_t *ret_itt)
691 {
692         struct iscsi_session *session = conn->session;
693         struct iscsi_cmd_task *ctask;
694         uint32_t itt;
695
696         if (hdr->itt != RESERVED_ITT) {
697                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
698                     (session->age << ISCSI_AGE_SHIFT)) {
699                         printk(KERN_ERR "iscsi: received itt %x expected "
700                                 "session age (%x)\n", (__force u32)hdr->itt,
701                                 session->age & ISCSI_AGE_MASK);
702                         return ISCSI_ERR_BAD_ITT;
703                 }
704
705                 if (((__force u32)hdr->itt & ISCSI_CID_MASK) !=
706                     (conn->id << ISCSI_CID_SHIFT)) {
707                         printk(KERN_ERR "iscsi: received itt %x, expected "
708                                 "CID (%x)\n", (__force u32)hdr->itt, conn->id);
709                         return ISCSI_ERR_BAD_ITT;
710                 }
711                 itt = get_itt(hdr->itt);
712         } else
713                 itt = ~0U;
714
715         if (itt < session->cmds_max) {
716                 ctask = session->cmds[itt];
717
718                 if (!ctask->sc) {
719                         printk(KERN_INFO "iscsi: dropping ctask with "
720                                "itt 0x%x\n", ctask->itt);
721                         /* force drop */
722                         return ISCSI_ERR_NO_SCSI_CMD;
723                 }
724
725                 if (ctask->sc->SCp.phase != session->age) {
726                         printk(KERN_ERR "iscsi: ctask's session age %d, "
727                                 "expected %d\n", ctask->sc->SCp.phase,
728                                 session->age);
729                         return ISCSI_ERR_SESSION_FAILED;
730                 }
731         }
732
733         *ret_itt = itt;
734         return 0;
735 }
736 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
737
738 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
739 {
740         struct iscsi_session *session = conn->session;
741         unsigned long flags;
742
743         spin_lock_irqsave(&session->lock, flags);
744         if (session->state == ISCSI_STATE_FAILED) {
745                 spin_unlock_irqrestore(&session->lock, flags);
746                 return;
747         }
748
749         if (conn->stop_stage == 0)
750                 session->state = ISCSI_STATE_FAILED;
751         spin_unlock_irqrestore(&session->lock, flags);
752         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
753         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
754         iscsi_conn_error(conn->cls_conn, err);
755 }
756 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
757
758 static void iscsi_prep_mtask(struct iscsi_conn *conn,
759                              struct iscsi_mgmt_task *mtask)
760 {
761         struct iscsi_session *session = conn->session;
762         struct iscsi_hdr *hdr = mtask->hdr;
763         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
764
765         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
766             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
767                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
768         /*
769          * pre-format CmdSN for outgoing PDU.
770          */
771         nop->cmdsn = cpu_to_be32(session->cmdsn);
772         if (hdr->itt != RESERVED_ITT) {
773                 hdr->itt = build_itt(mtask->itt, conn->id, session->age);
774                 /*
775                  * TODO: We always use immediate, so we never hit this.
776                  * If we start to send tmfs or nops as non-immediate then
777                  * we should start checking the cmdsn numbers for mgmt tasks.
778                  */
779                 if (conn->c_stage == ISCSI_CONN_STARTED &&
780                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
781                         session->queued_cmdsn++;
782                         session->cmdsn++;
783                 }
784         }
785
786         if (session->tt->init_mgmt_task)
787                 session->tt->init_mgmt_task(conn, mtask);
788
789         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
790                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
791                    mtask->data_count);
792 }
793
794 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
795 {
796         struct iscsi_hdr *hdr = conn->mtask->hdr;
797         int rc;
798
799         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
800                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
801         spin_unlock_bh(&conn->session->lock);
802
803         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
804         spin_lock_bh(&conn->session->lock);
805         if (rc)
806                 return rc;
807
808         /* done with this in-progress mtask */
809         conn->mtask = NULL;
810         return 0;
811 }
812
813 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
814 {
815         struct iscsi_session *session = conn->session;
816
817         /*
818          * Check for iSCSI window and take care of CmdSN wrap-around
819          */
820         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
821                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
822                            "CmdSN %u/%u\n", session->exp_cmdsn,
823                            session->max_cmdsn, session->cmdsn,
824                            session->queued_cmdsn);
825                 return -ENOSPC;
826         }
827         return 0;
828 }
829
830 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
831 {
832         struct iscsi_cmd_task *ctask = conn->ctask;
833         int rc;
834
835         __iscsi_get_ctask(ctask);
836         spin_unlock_bh(&conn->session->lock);
837         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
838         spin_lock_bh(&conn->session->lock);
839         __iscsi_put_ctask(ctask);
840         if (!rc)
841                 /* done with this ctask */
842                 conn->ctask = NULL;
843         return rc;
844 }
845
846 /**
847  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
848  * @ctask: ctask to requeue
849  *
850  * LLDs that need to run a ctask from the session workqueue should call
851  * this. The session lock must be held.
852  */
853 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
854 {
855         struct iscsi_conn *conn = ctask->conn;
856
857         list_move_tail(&ctask->running, &conn->requeue);
858         scsi_queue_work(conn->session->host, &conn->xmitwork);
859 }
860 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
861
862 /**
863  * iscsi_data_xmit - xmit any command into the scheduled connection
864  * @conn: iscsi connection
865  *
866  * Notes:
867  *      The function can return -EAGAIN in which case the caller must
868  *      re-schedule it again later or recover. '0' return code means
869  *      successful xmit.
870  **/
871 static int iscsi_data_xmit(struct iscsi_conn *conn)
872 {
873         int rc = 0;
874
875         spin_lock_bh(&conn->session->lock);
876         if (unlikely(conn->suspend_tx)) {
877                 debug_scsi("conn %d Tx suspended!\n", conn->id);
878                 spin_unlock_bh(&conn->session->lock);
879                 return -ENODATA;
880         }
881
882         if (conn->ctask) {
883                 rc = iscsi_xmit_ctask(conn);
884                 if (rc)
885                         goto again;
886         }
887
888         if (conn->mtask) {
889                 rc = iscsi_xmit_mtask(conn);
890                 if (rc)
891                         goto again;
892         }
893
894         /*
895          * process mgmt pdus like nops before commands since we should
896          * only have one nop-out as a ping from us and targets should not
897          * overflow us with nop-ins
898          */
899 check_mgmt:
900         while (!list_empty(&conn->mgmtqueue)) {
901                 conn->mtask = list_entry(conn->mgmtqueue.next,
902                                          struct iscsi_mgmt_task, running);
903                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
904                         iscsi_free_mgmt_task(conn, conn->mtask);
905                         conn->mtask = NULL;
906                         continue;
907                 }
908
909                 iscsi_prep_mtask(conn, conn->mtask);
910                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
911                 rc = iscsi_xmit_mtask(conn);
912                 if (rc)
913                         goto again;
914         }
915
916         /* process pending command queue */
917         while (!list_empty(&conn->xmitqueue)) {
918                 if (conn->tmf_state == TMF_QUEUED)
919                         break;
920
921                 conn->ctask = list_entry(conn->xmitqueue.next,
922                                          struct iscsi_cmd_task, running);
923                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
924                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
925                         continue;
926                 }
927                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
928                         fail_command(conn, conn->ctask, DID_ABORT << 16);
929                         continue;
930                 }
931
932                 conn->ctask->state = ISCSI_TASK_RUNNING;
933                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
934                 rc = iscsi_xmit_ctask(conn);
935                 if (rc)
936                         goto again;
937                 /*
938                  * we could continuously get new ctask requests so
939                  * we need to check the mgmt queue for nops that need to
940                  * be sent to aviod starvation
941                  */
942                 if (!list_empty(&conn->mgmtqueue))
943                         goto check_mgmt;
944         }
945
946         while (!list_empty(&conn->requeue)) {
947                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
948                         break;
949
950                 /*
951                  * we always do fastlogout - conn stop code will clean up.
952                  */
953                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
954                         break;
955
956                 conn->ctask = list_entry(conn->requeue.next,
957                                          struct iscsi_cmd_task, running);
958                 conn->ctask->state = ISCSI_TASK_RUNNING;
959                 list_move_tail(conn->requeue.next, &conn->run_list);
960                 rc = iscsi_xmit_ctask(conn);
961                 if (rc)
962                         goto again;
963                 if (!list_empty(&conn->mgmtqueue))
964                         goto check_mgmt;
965         }
966         spin_unlock_bh(&conn->session->lock);
967         return -ENODATA;
968
969 again:
970         if (unlikely(conn->suspend_tx))
971                 rc = -ENODATA;
972         spin_unlock_bh(&conn->session->lock);
973         return rc;
974 }
975
976 static void iscsi_xmitworker(struct work_struct *work)
977 {
978         struct iscsi_conn *conn =
979                 container_of(work, struct iscsi_conn, xmitwork);
980         int rc;
981         /*
982          * serialize Xmit worker on a per-connection basis.
983          */
984         do {
985                 rc = iscsi_data_xmit(conn);
986         } while (rc >= 0 || rc == -EAGAIN);
987 }
988
989 enum {
990         FAILURE_BAD_HOST = 1,
991         FAILURE_SESSION_FAILED,
992         FAILURE_SESSION_FREED,
993         FAILURE_WINDOW_CLOSED,
994         FAILURE_OOM,
995         FAILURE_SESSION_TERMINATE,
996         FAILURE_SESSION_IN_RECOVERY,
997         FAILURE_SESSION_RECOVERY_TIMEOUT,
998         FAILURE_SESSION_LOGGING_OUT,
999         FAILURE_SESSION_NOT_READY,
1000 };
1001
1002 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1003 {
1004         struct Scsi_Host *host;
1005         int reason = 0;
1006         struct iscsi_session *session;
1007         struct iscsi_conn *conn;
1008         struct iscsi_cmd_task *ctask = NULL;
1009
1010         sc->scsi_done = done;
1011         sc->result = 0;
1012         sc->SCp.ptr = NULL;
1013
1014         host = sc->device->host;
1015         spin_unlock(host->host_lock);
1016
1017         session = iscsi_hostdata(host->hostdata);
1018         spin_lock(&session->lock);
1019
1020         reason = iscsi_session_chkready(session_to_cls(session));
1021         if (reason) {
1022                 sc->result = reason;
1023                 goto fault;
1024         }
1025
1026         /*
1027          * ISCSI_STATE_FAILED is a temp. state. The recovery
1028          * code will decide what is best to do with command queued
1029          * during this time
1030          */
1031         if (session->state != ISCSI_STATE_LOGGED_IN &&
1032             session->state != ISCSI_STATE_FAILED) {
1033                 /*
1034                  * to handle the race between when we set the recovery state
1035                  * and block the session we requeue here (commands could
1036                  * be entering our queuecommand while a block is starting
1037                  * up because the block code is not locked)
1038                  */
1039                 switch (session->state) {
1040                 case ISCSI_STATE_IN_RECOVERY:
1041                         reason = FAILURE_SESSION_IN_RECOVERY;
1042                         sc->result = DID_IMM_RETRY << 16;
1043                         break;
1044                 case ISCSI_STATE_LOGGING_OUT:
1045                         reason = FAILURE_SESSION_LOGGING_OUT;
1046                         sc->result = DID_IMM_RETRY << 16;
1047                         break;
1048                 case ISCSI_STATE_RECOVERY_FAILED:
1049                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1050                         sc->result = DID_NO_CONNECT << 16;
1051                         break;
1052                 case ISCSI_STATE_TERMINATE:
1053                         reason = FAILURE_SESSION_TERMINATE;
1054                         sc->result = DID_NO_CONNECT << 16;
1055                         break;
1056                 default:
1057                         reason = FAILURE_SESSION_FREED;
1058                         sc->result = DID_NO_CONNECT << 16;
1059                 }
1060                 goto fault;
1061         }
1062
1063         conn = session->leadconn;
1064         if (!conn) {
1065                 reason = FAILURE_SESSION_FREED;
1066                 sc->result = DID_NO_CONNECT << 16;
1067                 goto fault;
1068         }
1069
1070         if (iscsi_check_cmdsn_window_closed(conn)) {
1071                 reason = FAILURE_WINDOW_CLOSED;
1072                 goto reject;
1073         }
1074
1075         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1076                          sizeof(void*))) {
1077                 reason = FAILURE_OOM;
1078                 goto reject;
1079         }
1080         session->queued_cmdsn++;
1081
1082         sc->SCp.phase = session->age;
1083         sc->SCp.ptr = (char *)ctask;
1084
1085         atomic_set(&ctask->refcount, 1);
1086         ctask->state = ISCSI_TASK_PENDING;
1087         ctask->conn = conn;
1088         ctask->sc = sc;
1089         INIT_LIST_HEAD(&ctask->running);
1090
1091         list_add_tail(&ctask->running, &conn->xmitqueue);
1092         spin_unlock(&session->lock);
1093
1094         scsi_queue_work(host, &conn->xmitwork);
1095         spin_lock(host->host_lock);
1096         return 0;
1097
1098 reject:
1099         spin_unlock(&session->lock);
1100         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1101         spin_lock(host->host_lock);
1102         return SCSI_MLQUEUE_HOST_BUSY;
1103
1104 fault:
1105         spin_unlock(&session->lock);
1106         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1107         scsi_set_resid(sc, scsi_bufflen(sc));
1108         sc->scsi_done(sc);
1109         spin_lock(host->host_lock);
1110         return 0;
1111 }
1112 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1113
1114 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1115 {
1116         if (depth > ISCSI_MAX_CMD_PER_LUN)
1117                 depth = ISCSI_MAX_CMD_PER_LUN;
1118         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1119         return sdev->queue_depth;
1120 }
1121 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1122
1123 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1124 {
1125         struct iscsi_session *session = class_to_transport_session(cls_session);
1126
1127         spin_lock_bh(&session->lock);
1128         if (session->state != ISCSI_STATE_LOGGED_IN) {
1129                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1130                 if (session->leadconn)
1131                         wake_up(&session->leadconn->ehwait);
1132         }
1133         spin_unlock_bh(&session->lock);
1134 }
1135 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1136
1137 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1138 {
1139         struct Scsi_Host *host = sc->device->host;
1140         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1141         struct iscsi_conn *conn = session->leadconn;
1142
1143         mutex_lock(&session->eh_mutex);
1144         spin_lock_bh(&session->lock);
1145         if (session->state == ISCSI_STATE_TERMINATE) {
1146 failed:
1147                 debug_scsi("failing host reset: session terminated "
1148                            "[CID %d age %d]\n", conn->id, session->age);
1149                 spin_unlock_bh(&session->lock);
1150                 mutex_unlock(&session->eh_mutex);
1151                 return FAILED;
1152         }
1153
1154         spin_unlock_bh(&session->lock);
1155         mutex_unlock(&session->eh_mutex);
1156         /*
1157          * we drop the lock here but the leadconn cannot be destoyed while
1158          * we are in the scsi eh
1159          */
1160         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1161
1162         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1163         wait_event_interruptible(conn->ehwait,
1164                                  session->state == ISCSI_STATE_TERMINATE ||
1165                                  session->state == ISCSI_STATE_LOGGED_IN ||
1166                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1167         if (signal_pending(current))
1168                 flush_signals(current);
1169
1170         mutex_lock(&session->eh_mutex);
1171         spin_lock_bh(&session->lock);
1172         if (session->state == ISCSI_STATE_LOGGED_IN)
1173                 printk(KERN_INFO "iscsi: host reset succeeded\n");
1174         else
1175                 goto failed;
1176         spin_unlock_bh(&session->lock);
1177         mutex_unlock(&session->eh_mutex);
1178         return SUCCESS;
1179 }
1180 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1181
1182 static void iscsi_tmf_timedout(unsigned long data)
1183 {
1184         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1185         struct iscsi_session *session = conn->session;
1186
1187         spin_lock(&session->lock);
1188         if (conn->tmf_state == TMF_QUEUED) {
1189                 conn->tmf_state = TMF_TIMEDOUT;
1190                 debug_scsi("tmf timedout\n");
1191                 /* unblock eh_abort() */
1192                 wake_up(&conn->ehwait);
1193         }
1194         spin_unlock(&session->lock);
1195 }
1196
1197 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1198                                    struct iscsi_tm *hdr, int age,
1199                                    int timeout)
1200 {
1201         struct iscsi_session *session = conn->session;
1202         struct iscsi_mgmt_task *mtask;
1203
1204         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1205                                       NULL, 0);
1206         if (!mtask) {
1207                 spin_unlock_bh(&session->lock);
1208                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1209                 spin_lock_bh(&session->lock);
1210                 debug_scsi("tmf exec failure\n");
1211                 return -EPERM;
1212         }
1213         conn->tmfcmd_pdus_cnt++;
1214         conn->tmf_timer.expires = timeout * HZ + jiffies;
1215         conn->tmf_timer.function = iscsi_tmf_timedout;
1216         conn->tmf_timer.data = (unsigned long)conn;
1217         add_timer(&conn->tmf_timer);
1218         debug_scsi("tmf set timeout\n");
1219
1220         spin_unlock_bh(&session->lock);
1221         mutex_unlock(&session->eh_mutex);
1222         scsi_queue_work(session->host, &conn->xmitwork);
1223
1224         /*
1225          * block eh thread until:
1226          *
1227          * 1) tmf response
1228          * 2) tmf timeout
1229          * 3) session is terminated or restarted or userspace has
1230          * given up on recovery
1231          */
1232         wait_event_interruptible(conn->ehwait, age != session->age ||
1233                                  session->state != ISCSI_STATE_LOGGED_IN ||
1234                                  conn->tmf_state != TMF_QUEUED);
1235         if (signal_pending(current))
1236                 flush_signals(current);
1237         del_timer_sync(&conn->tmf_timer);
1238
1239         mutex_lock(&session->eh_mutex);
1240         spin_lock_bh(&session->lock);
1241         /* if the session drops it will clean up the mtask */
1242         if (age != session->age ||
1243             session->state != ISCSI_STATE_LOGGED_IN)
1244                 return -ENOTCONN;
1245         return 0;
1246 }
1247
1248 /*
1249  * Fail commands. session lock held and recv side suspended and xmit
1250  * thread flushed
1251  */
1252 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1253                               int error)
1254 {
1255         struct iscsi_cmd_task *ctask, *tmp;
1256
1257         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1258                 conn->ctask = NULL;
1259
1260         /* flush pending */
1261         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1262                 if (lun == ctask->sc->device->lun || lun == -1) {
1263                         debug_scsi("failing pending sc %p itt 0x%x\n",
1264                                    ctask->sc, ctask->itt);
1265                         fail_command(conn, ctask, error << 16);
1266                 }
1267         }
1268
1269         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1270                 if (lun == ctask->sc->device->lun || lun == -1) {
1271                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1272                                    ctask->sc, ctask->itt);
1273                         fail_command(conn, ctask, error << 16);
1274                 }
1275         }
1276
1277         /* fail all other running */
1278         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1279                 if (lun == ctask->sc->device->lun || lun == -1) {
1280                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1281                                    ctask->sc, ctask->itt);
1282                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1283                 }
1284         }
1285 }
1286
1287 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1288 {
1289         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1290         scsi_flush_work(conn->session->host);
1291 }
1292
1293 static void iscsi_start_tx(struct iscsi_conn *conn)
1294 {
1295         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1296         scsi_queue_work(conn->session->host, &conn->xmitwork);
1297 }
1298
1299 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1300 {
1301         struct iscsi_cls_session *cls_session;
1302         struct iscsi_session *session;
1303         struct iscsi_conn *conn;
1304         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1305
1306         cls_session = starget_to_session(scsi_target(scmd->device));
1307         session = class_to_transport_session(cls_session);
1308
1309         debug_scsi("scsi cmd %p timedout\n", scmd);
1310
1311         spin_lock(&session->lock);
1312         if (session->state != ISCSI_STATE_LOGGED_IN) {
1313                 /*
1314                  * We are probably in the middle of iscsi recovery so let
1315                  * that complete and handle the error.
1316                  */
1317                 rc = EH_RESET_TIMER;
1318                 goto done;
1319         }
1320
1321         conn = session->leadconn;
1322         if (!conn) {
1323                 /* In the middle of shuting down */
1324                 rc = EH_RESET_TIMER;
1325                 goto done;
1326         }
1327
1328         if (!conn->recv_timeout && !conn->ping_timeout)
1329                 goto done;
1330         /*
1331          * if the ping timedout then we are in the middle of cleaning up
1332          * and can let the iscsi eh handle it
1333          */
1334         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1335                             (conn->ping_timeout * HZ), jiffies))
1336                 rc = EH_RESET_TIMER;
1337         /*
1338          * if we are about to check the transport then give the command
1339          * more time
1340          */
1341         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1342                            jiffies))
1343                 rc = EH_RESET_TIMER;
1344         /* if in the middle of checking the transport then give us more time */
1345         if (conn->ping_mtask)
1346                 rc = EH_RESET_TIMER;
1347 done:
1348         spin_unlock(&session->lock);
1349         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1350         return rc;
1351 }
1352
1353 static void iscsi_check_transport_timeouts(unsigned long data)
1354 {
1355         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1356         struct iscsi_session *session = conn->session;
1357         unsigned long timeout, next_timeout = 0, last_recv;
1358
1359         spin_lock(&session->lock);
1360         if (session->state != ISCSI_STATE_LOGGED_IN)
1361                 goto done;
1362
1363         timeout = conn->recv_timeout;
1364         if (!timeout)
1365                 goto done;
1366
1367         timeout *= HZ;
1368         last_recv = conn->last_recv;
1369         if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
1370                            jiffies)) {
1371                 printk(KERN_ERR "ping timeout of %d secs expired, "
1372                        "last rx %lu, last ping %lu, now %lu\n",
1373                        conn->ping_timeout, last_recv,
1374                        conn->last_ping, jiffies);
1375                 spin_unlock(&session->lock);
1376                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1377                 return;
1378         }
1379
1380         if (time_before_eq(last_recv + timeout, jiffies)) {
1381                 if (time_before_eq(conn->last_ping, last_recv)) {
1382                         /* send a ping to try to provoke some traffic */
1383                         debug_scsi("Sending nopout as ping on conn %p\n", conn);
1384                         iscsi_send_nopout(conn, NULL);
1385                 }
1386                 next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
1387         } else
1388                 next_timeout = last_recv + timeout;
1389
1390         debug_scsi("Setting next tmo %lu\n", next_timeout);
1391         mod_timer(&conn->transport_timer, next_timeout);
1392 done:
1393         spin_unlock(&session->lock);
1394 }
1395
1396 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1397                                       struct iscsi_tm *hdr)
1398 {
1399         memset(hdr, 0, sizeof(*hdr));
1400         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1401         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1402         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1403         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1404         hdr->rtt = ctask->hdr->itt;
1405         hdr->refcmdsn = ctask->hdr->cmdsn;
1406 }
1407
1408 int iscsi_eh_abort(struct scsi_cmnd *sc)
1409 {
1410         struct Scsi_Host *host = sc->device->host;
1411         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1412         struct iscsi_conn *conn;
1413         struct iscsi_cmd_task *ctask;
1414         struct iscsi_tm *hdr;
1415         int rc, age;
1416
1417         mutex_lock(&session->eh_mutex);
1418         spin_lock_bh(&session->lock);
1419         /*
1420          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1421          * got the command.
1422          */
1423         if (!sc->SCp.ptr) {
1424                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1425                 spin_unlock_bh(&session->lock);
1426                 mutex_unlock(&session->eh_mutex);
1427                 return SUCCESS;
1428         }
1429
1430         /*
1431          * If we are not logged in or we have started a new session
1432          * then let the host reset code handle this
1433          */
1434         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1435             sc->SCp.phase != session->age) {
1436                 spin_unlock_bh(&session->lock);
1437                 mutex_unlock(&session->eh_mutex);
1438                 return FAILED;
1439         }
1440
1441         conn = session->leadconn;
1442         conn->eh_abort_cnt++;
1443         age = session->age;
1444
1445         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1446         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1447
1448         /* ctask completed before time out */
1449         if (!ctask->sc) {
1450                 debug_scsi("sc completed while abort in progress\n");
1451                 goto success;
1452         }
1453
1454         if (ctask->state == ISCSI_TASK_PENDING) {
1455                 fail_command(conn, ctask, DID_ABORT << 16);
1456                 goto success;
1457         }
1458
1459         /* only have one tmf outstanding at a time */
1460         if (conn->tmf_state != TMF_INITIAL)
1461                 goto failed;
1462         conn->tmf_state = TMF_QUEUED;
1463
1464         hdr = &conn->tmhdr;
1465         iscsi_prep_abort_task_pdu(ctask, hdr);
1466
1467         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1468                 rc = FAILED;
1469                 goto failed;
1470         }
1471
1472         switch (conn->tmf_state) {
1473         case TMF_SUCCESS:
1474                 spin_unlock_bh(&session->lock);
1475                 iscsi_suspend_tx(conn);
1476                 /*
1477                  * clean up task if aborted. grab the recv lock as a writer
1478                  */
1479                 write_lock_bh(conn->recv_lock);
1480                 spin_lock(&session->lock);
1481                 fail_command(conn, ctask, DID_ABORT << 16);
1482                 conn->tmf_state = TMF_INITIAL;
1483                 spin_unlock(&session->lock);
1484                 write_unlock_bh(conn->recv_lock);
1485                 iscsi_start_tx(conn);
1486                 goto success_unlocked;
1487         case TMF_TIMEDOUT:
1488                 spin_unlock_bh(&session->lock);
1489                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1490                 goto failed_unlocked;
1491         case TMF_NOT_FOUND:
1492                 if (!sc->SCp.ptr) {
1493                         conn->tmf_state = TMF_INITIAL;
1494                         /* ctask completed before tmf abort response */
1495                         debug_scsi("sc completed while abort in progress\n");
1496                         goto success;
1497                 }
1498                 /* fall through */
1499         default:
1500                 conn->tmf_state = TMF_INITIAL;
1501                 goto failed;
1502         }
1503
1504 success:
1505         spin_unlock_bh(&session->lock);
1506 success_unlocked:
1507         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1508         mutex_unlock(&session->eh_mutex);
1509         return SUCCESS;
1510
1511 failed:
1512         spin_unlock_bh(&session->lock);
1513 failed_unlocked:
1514         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1515                     ctask ? ctask->itt : 0);
1516         mutex_unlock(&session->eh_mutex);
1517         return FAILED;
1518 }
1519 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1520
1521 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1522 {
1523         memset(hdr, 0, sizeof(*hdr));
1524         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1525         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1526         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1527         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1528         hdr->rtt = RESERVED_ITT;
1529 }
1530
1531 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1532 {
1533         struct Scsi_Host *host = sc->device->host;
1534         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1535         struct iscsi_conn *conn;
1536         struct iscsi_tm *hdr;
1537         int rc = FAILED;
1538
1539         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1540
1541         mutex_lock(&session->eh_mutex);
1542         spin_lock_bh(&session->lock);
1543         /*
1544          * Just check if we are not logged in. We cannot check for
1545          * the phase because the reset could come from a ioctl.
1546          */
1547         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1548                 goto unlock;
1549         conn = session->leadconn;
1550
1551         /* only have one tmf outstanding at a time */
1552         if (conn->tmf_state != TMF_INITIAL)
1553                 goto unlock;
1554         conn->tmf_state = TMF_QUEUED;
1555
1556         hdr = &conn->tmhdr;
1557         iscsi_prep_lun_reset_pdu(sc, hdr);
1558
1559         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1560                                     session->lu_reset_timeout)) {
1561                 rc = FAILED;
1562                 goto unlock;
1563         }
1564
1565         switch (conn->tmf_state) {
1566         case TMF_SUCCESS:
1567                 break;
1568         case TMF_TIMEDOUT:
1569                 spin_unlock_bh(&session->lock);
1570                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1571                 goto done;
1572         default:
1573                 conn->tmf_state = TMF_INITIAL;
1574                 goto unlock;
1575         }
1576
1577         rc = SUCCESS;
1578         spin_unlock_bh(&session->lock);
1579
1580         iscsi_suspend_tx(conn);
1581         /* need to grab the recv lock then session lock */
1582         write_lock_bh(conn->recv_lock);
1583         spin_lock(&session->lock);
1584         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1585         conn->tmf_state = TMF_INITIAL;
1586         spin_unlock(&session->lock);
1587         write_unlock_bh(conn->recv_lock);
1588
1589         iscsi_start_tx(conn);
1590         goto done;
1591
1592 unlock:
1593         spin_unlock_bh(&session->lock);
1594 done:
1595         debug_scsi("iscsi_eh_device_reset %s\n",
1596                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1597         mutex_unlock(&session->eh_mutex);
1598         return rc;
1599 }
1600 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1601
1602 /*
1603  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1604  * should be accessed via kfifo_{get,put} on q->queue.
1605  * Optionally, the caller can obtain the array of object pointers
1606  * by passing in a non-NULL @items pointer
1607  */
1608 int
1609 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1610 {
1611         int i, num_arrays = 1;
1612
1613         memset(q, 0, sizeof(*q));
1614
1615         q->max = max;
1616
1617         /* If the user passed an items pointer, he wants a copy of
1618          * the array. */
1619         if (items)
1620                 num_arrays++;
1621         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1622         if (q->pool == NULL)
1623                 goto enomem;
1624
1625         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1626                               GFP_KERNEL, NULL);
1627         if (q->queue == ERR_PTR(-ENOMEM))
1628                 goto enomem;
1629
1630         for (i = 0; i < max; i++) {
1631                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1632                 if (q->pool[i] == NULL) {
1633                         q->max = i;
1634                         goto enomem;
1635                 }
1636                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1637         }
1638
1639         if (items) {
1640                 *items = q->pool + max;
1641                 memcpy(*items, q->pool, max * sizeof(void *));
1642         }
1643
1644         return 0;
1645
1646 enomem:
1647         iscsi_pool_free(q);
1648         return -ENOMEM;
1649 }
1650 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1651
1652 void iscsi_pool_free(struct iscsi_pool *q)
1653 {
1654         int i;
1655
1656         for (i = 0; i < q->max; i++)
1657                 kfree(q->pool[i]);
1658         if (q->pool)
1659                 kfree(q->pool);
1660 }
1661 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1662
1663 /*
1664  * iSCSI Session's hostdata organization:
1665  *
1666  *    *------------------* <== hostdata_session(host->hostdata)
1667  *    | ptr to class sess|
1668  *    |------------------| <== iscsi_hostdata(host->hostdata)
1669  *    | iscsi_session    |
1670  *    *------------------*
1671  */
1672
1673 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1674                                  _sz % sizeof(unsigned long))
1675
1676 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1677
1678 /**
1679  * iscsi_session_setup - create iscsi cls session and host and session
1680  * @scsit: scsi transport template
1681  * @iscsit: iscsi transport template
1682  * @cmds_max: scsi host can queue
1683  * @qdepth: scsi host cmds per lun
1684  * @cmd_task_size: LLD ctask private data size
1685  * @mgmt_task_size: LLD mtask private data size
1686  * @initial_cmdsn: initial CmdSN
1687  * @hostno: host no allocated
1688  *
1689  * This can be used by software iscsi_transports that allocate
1690  * a session per scsi host.
1691  **/
1692 struct iscsi_cls_session *
1693 iscsi_session_setup(struct iscsi_transport *iscsit,
1694                     struct scsi_transport_template *scsit,
1695                     uint16_t cmds_max, uint16_t qdepth,
1696                     int cmd_task_size, int mgmt_task_size,
1697                     uint32_t initial_cmdsn, uint32_t *hostno)
1698 {
1699         struct Scsi_Host *shost;
1700         struct iscsi_session *session;
1701         struct iscsi_cls_session *cls_session;
1702         int cmd_i;
1703
1704         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1705                 if (qdepth != 0)
1706                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1707                               "Queue depth must be between 1 and %d.\n",
1708                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1709                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1710         }
1711
1712         if (!is_power_of_2(cmds_max) ||
1713             cmds_max >= ISCSI_MGMT_ITT_OFFSET) {
1714                 if (cmds_max != 0)
1715                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1716                                "can_queue must be a power of 2 and between "
1717                                "2 and %d - setting to %d.\n", cmds_max,
1718                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1719                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1720         }
1721
1722         shost = scsi_host_alloc(iscsit->host_template,
1723                                 hostdata_privsize(sizeof(*session)));
1724         if (!shost)
1725                 return NULL;
1726
1727         /* the iscsi layer takes one task for reserve */
1728         shost->can_queue = cmds_max - 1;
1729         shost->cmd_per_lun = qdepth;
1730         shost->max_id = 1;
1731         shost->max_channel = 0;
1732         shost->max_lun = iscsit->max_lun;
1733         shost->max_cmd_len = iscsit->max_cmd_len;
1734         shost->transportt = scsit;
1735         shost->transportt->create_work_queue = 1;
1736         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1737         *hostno = shost->host_no;
1738
1739         session = iscsi_hostdata(shost->hostdata);
1740         memset(session, 0, sizeof(struct iscsi_session));
1741         session->host = shost;
1742         session->state = ISCSI_STATE_FREE;
1743         session->fast_abort = 1;
1744         session->lu_reset_timeout = 15;
1745         session->abort_timeout = 10;
1746         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1747         session->cmds_max = cmds_max;
1748         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1749         session->exp_cmdsn = initial_cmdsn + 1;
1750         session->max_cmdsn = initial_cmdsn + 1;
1751         session->max_r2t = 1;
1752         session->tt = iscsit;
1753         mutex_init(&session->eh_mutex);
1754
1755         /* initialize SCSI PDU commands pool */
1756         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1757                             (void***)&session->cmds,
1758                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1759                 goto cmdpool_alloc_fail;
1760
1761         /* pre-format cmds pool with ITT */
1762         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1763                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1764
1765                 if (cmd_task_size)
1766                         ctask->dd_data = &ctask[1];
1767                 ctask->itt = cmd_i;
1768                 INIT_LIST_HEAD(&ctask->running);
1769         }
1770
1771         spin_lock_init(&session->lock);
1772
1773         /* initialize immediate command pool */
1774         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1775                            (void***)&session->mgmt_cmds,
1776                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1777                 goto mgmtpool_alloc_fail;
1778
1779
1780         /* pre-format immediate cmds pool with ITT */
1781         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1782                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1783
1784                 if (mgmt_task_size)
1785                         mtask->dd_data = &mtask[1];
1786                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1787                 INIT_LIST_HEAD(&mtask->running);
1788         }
1789
1790         if (scsi_add_host(shost, NULL))
1791                 goto add_host_fail;
1792
1793         if (!try_module_get(iscsit->owner))
1794                 goto cls_session_fail;
1795
1796         cls_session = iscsi_create_session(shost, iscsit, 0);
1797         if (!cls_session)
1798                 goto module_put;
1799         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1800
1801         return cls_session;
1802
1803 module_put:
1804         module_put(iscsit->owner);
1805 cls_session_fail:
1806         scsi_remove_host(shost);
1807 add_host_fail:
1808         iscsi_pool_free(&session->mgmtpool);
1809 mgmtpool_alloc_fail:
1810         iscsi_pool_free(&session->cmdpool);
1811 cmdpool_alloc_fail:
1812         scsi_host_put(shost);
1813         return NULL;
1814 }
1815 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1816
1817 /**
1818  * iscsi_session_teardown - destroy session, host, and cls_session
1819  * shost: scsi host
1820  *
1821  * This can be used by software iscsi_transports that allocate
1822  * a session per scsi host.
1823  **/
1824 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1825 {
1826         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1827         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1828         struct module *owner = cls_session->transport->owner;
1829
1830         iscsi_remove_session(cls_session);
1831         scsi_remove_host(shost);
1832
1833         iscsi_pool_free(&session->mgmtpool);
1834         iscsi_pool_free(&session->cmdpool);
1835
1836         kfree(session->password);
1837         kfree(session->password_in);
1838         kfree(session->username);
1839         kfree(session->username_in);
1840         kfree(session->targetname);
1841         kfree(session->netdev);
1842         kfree(session->hwaddress);
1843         kfree(session->initiatorname);
1844
1845         iscsi_free_session(cls_session);
1846         scsi_host_put(shost);
1847         module_put(owner);
1848 }
1849 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1850
1851 /**
1852  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1853  * @cls_session: iscsi_cls_session
1854  * @conn_idx: cid
1855  **/
1856 struct iscsi_cls_conn *
1857 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1858 {
1859         struct iscsi_session *session = class_to_transport_session(cls_session);
1860         struct iscsi_conn *conn;
1861         struct iscsi_cls_conn *cls_conn;
1862         char *data;
1863
1864         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1865         if (!cls_conn)
1866                 return NULL;
1867         conn = cls_conn->dd_data;
1868         memset(conn, 0, sizeof(*conn));
1869
1870         conn->session = session;
1871         conn->cls_conn = cls_conn;
1872         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1873         conn->id = conn_idx;
1874         conn->exp_statsn = 0;
1875         conn->tmf_state = TMF_INITIAL;
1876
1877         init_timer(&conn->transport_timer);
1878         conn->transport_timer.data = (unsigned long)conn;
1879         conn->transport_timer.function = iscsi_check_transport_timeouts;
1880
1881         INIT_LIST_HEAD(&conn->run_list);
1882         INIT_LIST_HEAD(&conn->mgmt_run_list);
1883         INIT_LIST_HEAD(&conn->mgmtqueue);
1884         INIT_LIST_HEAD(&conn->xmitqueue);
1885         INIT_LIST_HEAD(&conn->requeue);
1886         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1887
1888         /* allocate login_mtask used for the login/text sequences */
1889         spin_lock_bh(&session->lock);
1890         if (!__kfifo_get(session->mgmtpool.queue,
1891                          (void*)&conn->login_mtask,
1892                          sizeof(void*))) {
1893                 spin_unlock_bh(&session->lock);
1894                 goto login_mtask_alloc_fail;
1895         }
1896         spin_unlock_bh(&session->lock);
1897
1898         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1899         if (!data)
1900                 goto login_mtask_data_alloc_fail;
1901         conn->login_mtask->data = conn->data = data;
1902
1903         init_timer(&conn->tmf_timer);
1904         init_waitqueue_head(&conn->ehwait);
1905
1906         return cls_conn;
1907
1908 login_mtask_data_alloc_fail:
1909         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1910                     sizeof(void*));
1911 login_mtask_alloc_fail:
1912         iscsi_destroy_conn(cls_conn);
1913         return NULL;
1914 }
1915 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1916
1917 /**
1918  * iscsi_conn_teardown - teardown iscsi connection
1919  * cls_conn: iscsi class connection
1920  *
1921  * TODO: we may need to make this into a two step process
1922  * like scsi-mls remove + put host
1923  */
1924 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1925 {
1926         struct iscsi_conn *conn = cls_conn->dd_data;
1927         struct iscsi_session *session = conn->session;
1928         unsigned long flags;
1929
1930         del_timer_sync(&conn->transport_timer);
1931
1932         spin_lock_bh(&session->lock);
1933         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1934         if (session->leadconn == conn) {
1935                 /*
1936                  * leading connection? then give up on recovery.
1937                  */
1938                 session->state = ISCSI_STATE_TERMINATE;
1939                 wake_up(&conn->ehwait);
1940         }
1941         spin_unlock_bh(&session->lock);
1942
1943         /*
1944          * Block until all in-progress commands for this connection
1945          * time out or fail.
1946          */
1947         for (;;) {
1948                 spin_lock_irqsave(session->host->host_lock, flags);
1949                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1950                         spin_unlock_irqrestore(session->host->host_lock, flags);
1951                         break;
1952                 }
1953                 spin_unlock_irqrestore(session->host->host_lock, flags);
1954                 msleep_interruptible(500);
1955                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1956                        "host_failed %d\n", session->host->host_busy,
1957                        session->host->host_failed);
1958                 /*
1959                  * force eh_abort() to unblock
1960                  */
1961                 wake_up(&conn->ehwait);
1962         }
1963
1964         /* flush queued up work because we free the connection below */
1965         iscsi_suspend_tx(conn);
1966
1967         spin_lock_bh(&session->lock);
1968         kfree(conn->data);
1969         kfree(conn->persistent_address);
1970         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1971                     sizeof(void*));
1972         if (session->leadconn == conn)
1973                 session->leadconn = NULL;
1974         spin_unlock_bh(&session->lock);
1975
1976         iscsi_destroy_conn(cls_conn);
1977 }
1978 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1979
1980 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1981 {
1982         struct iscsi_conn *conn = cls_conn->dd_data;
1983         struct iscsi_session *session = conn->session;
1984
1985         if (!session) {
1986                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1987                 return -EPERM;
1988         }
1989
1990         if ((session->imm_data_en || !session->initial_r2t_en) &&
1991              session->first_burst > session->max_burst) {
1992                 printk("iscsi: invalid burst lengths: "
1993                        "first_burst %d max_burst %d\n",
1994                        session->first_burst, session->max_burst);
1995                 return -EINVAL;
1996         }
1997
1998         if (conn->ping_timeout && !conn->recv_timeout) {
1999                 printk(KERN_ERR "iscsi: invalid recv timeout of zero "
2000                       "Using 5 seconds\n.");
2001                 conn->recv_timeout = 5;
2002         }
2003
2004         if (conn->recv_timeout && !conn->ping_timeout) {
2005                 printk(KERN_ERR "iscsi: invalid ping timeout of zero "
2006                       "Using 5 seconds.\n");
2007                 conn->ping_timeout = 5;
2008         }
2009
2010         spin_lock_bh(&session->lock);
2011         conn->c_stage = ISCSI_CONN_STARTED;
2012         session->state = ISCSI_STATE_LOGGED_IN;
2013         session->queued_cmdsn = session->cmdsn;
2014
2015         conn->last_recv = jiffies;
2016         conn->last_ping = jiffies;
2017         if (conn->recv_timeout && conn->ping_timeout)
2018                 mod_timer(&conn->transport_timer,
2019                           jiffies + (conn->recv_timeout * HZ));
2020
2021         switch(conn->stop_stage) {
2022         case STOP_CONN_RECOVER:
2023                 /*
2024                  * unblock eh_abort() if it is blocked. re-try all
2025                  * commands after successful recovery
2026                  */
2027                 conn->stop_stage = 0;
2028                 conn->tmf_state = TMF_INITIAL;
2029                 session->age++;
2030                 break;
2031         case STOP_CONN_TERM:
2032                 conn->stop_stage = 0;
2033                 break;
2034         default:
2035                 break;
2036         }
2037         spin_unlock_bh(&session->lock);
2038
2039         iscsi_unblock_session(session_to_cls(session));
2040         wake_up(&conn->ehwait);
2041         return 0;
2042 }
2043 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2044
2045 static void
2046 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2047 {
2048         struct iscsi_mgmt_task *mtask, *tmp;
2049
2050         /* handle pending */
2051         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2052                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2053                 iscsi_free_mgmt_task(conn, mtask);
2054         }
2055
2056         /* handle running */
2057         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2058                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2059                 iscsi_free_mgmt_task(conn, mtask);
2060         }
2061
2062         conn->mtask = NULL;
2063 }
2064
2065 static void iscsi_start_session_recovery(struct iscsi_session *session,
2066                                          struct iscsi_conn *conn, int flag)
2067 {
2068         int old_stop_stage;
2069
2070         del_timer_sync(&conn->transport_timer);
2071
2072         mutex_lock(&session->eh_mutex);
2073         spin_lock_bh(&session->lock);
2074         if (conn->stop_stage == STOP_CONN_TERM) {
2075                 spin_unlock_bh(&session->lock);
2076                 mutex_unlock(&session->eh_mutex);
2077                 return;
2078         }
2079
2080         /*
2081          * The LLD either freed/unset the lock on us, or userspace called
2082          * stop but did not create a proper connection (connection was never
2083          * bound or it was unbound then stop was called).
2084          */
2085         if (!conn->recv_lock) {
2086                 spin_unlock_bh(&session->lock);
2087                 mutex_unlock(&session->eh_mutex);
2088                 return;
2089         }
2090
2091         /*
2092          * When this is called for the in_login state, we only want to clean
2093          * up the login task and connection. We do not need to block and set
2094          * the recovery state again
2095          */
2096         if (flag == STOP_CONN_TERM)
2097                 session->state = ISCSI_STATE_TERMINATE;
2098         else if (conn->stop_stage != STOP_CONN_RECOVER)
2099                 session->state = ISCSI_STATE_IN_RECOVERY;
2100
2101         old_stop_stage = conn->stop_stage;
2102         conn->stop_stage = flag;
2103         conn->c_stage = ISCSI_CONN_STOPPED;
2104         spin_unlock_bh(&session->lock);
2105
2106         iscsi_suspend_tx(conn);
2107
2108         write_lock_bh(conn->recv_lock);
2109         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2110         write_unlock_bh(conn->recv_lock);
2111
2112         /*
2113          * for connection level recovery we should not calculate
2114          * header digest. conn->hdr_size used for optimization
2115          * in hdr_extract() and will be re-negotiated at
2116          * set_param() time.
2117          */
2118         if (flag == STOP_CONN_RECOVER) {
2119                 conn->hdrdgst_en = 0;
2120                 conn->datadgst_en = 0;
2121                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2122                     old_stop_stage != STOP_CONN_RECOVER) {
2123                         debug_scsi("blocking session\n");
2124                         iscsi_block_session(session_to_cls(session));
2125                 }
2126         }
2127
2128         /*
2129          * flush queues.
2130          */
2131         spin_lock_bh(&session->lock);
2132         fail_all_commands(conn, -1,
2133                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2134         flush_control_queues(session, conn);
2135         spin_unlock_bh(&session->lock);
2136         mutex_unlock(&session->eh_mutex);
2137 }
2138
2139 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2140 {
2141         struct iscsi_conn *conn = cls_conn->dd_data;
2142         struct iscsi_session *session = conn->session;
2143
2144         switch (flag) {
2145         case STOP_CONN_RECOVER:
2146         case STOP_CONN_TERM:
2147                 iscsi_start_session_recovery(session, conn, flag);
2148                 break;
2149         default:
2150                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
2151         }
2152 }
2153 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2154
2155 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2156                     struct iscsi_cls_conn *cls_conn, int is_leading)
2157 {
2158         struct iscsi_session *session = class_to_transport_session(cls_session);
2159         struct iscsi_conn *conn = cls_conn->dd_data;
2160
2161         spin_lock_bh(&session->lock);
2162         if (is_leading)
2163                 session->leadconn = conn;
2164         spin_unlock_bh(&session->lock);
2165
2166         /*
2167          * Unblock xmitworker(), Login Phase will pass through.
2168          */
2169         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2170         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2171         return 0;
2172 }
2173 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2174
2175
2176 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2177                     enum iscsi_param param, char *buf, int buflen)
2178 {
2179         struct iscsi_conn *conn = cls_conn->dd_data;
2180         struct iscsi_session *session = conn->session;
2181         uint32_t value;
2182
2183         switch(param) {
2184         case ISCSI_PARAM_FAST_ABORT:
2185                 sscanf(buf, "%d", &session->fast_abort);
2186                 break;
2187         case ISCSI_PARAM_ABORT_TMO:
2188                 sscanf(buf, "%d", &session->abort_timeout);
2189                 break;
2190         case ISCSI_PARAM_LU_RESET_TMO:
2191                 sscanf(buf, "%d", &session->lu_reset_timeout);
2192                 break;
2193         case ISCSI_PARAM_PING_TMO:
2194                 sscanf(buf, "%d", &conn->ping_timeout);
2195                 break;
2196         case ISCSI_PARAM_RECV_TMO:
2197                 sscanf(buf, "%d", &conn->recv_timeout);
2198                 break;
2199         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2200                 sscanf(buf, "%d", &conn->max_recv_dlength);
2201                 break;
2202         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2203                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2204                 break;
2205         case ISCSI_PARAM_HDRDGST_EN:
2206                 sscanf(buf, "%d", &conn->hdrdgst_en);
2207                 break;
2208         case ISCSI_PARAM_DATADGST_EN:
2209                 sscanf(buf, "%d", &conn->datadgst_en);
2210                 break;
2211         case ISCSI_PARAM_INITIAL_R2T_EN:
2212                 sscanf(buf, "%d", &session->initial_r2t_en);
2213                 break;
2214         case ISCSI_PARAM_MAX_R2T:
2215                 sscanf(buf, "%d", &session->max_r2t);
2216                 break;
2217         case ISCSI_PARAM_IMM_DATA_EN:
2218                 sscanf(buf, "%d", &session->imm_data_en);
2219                 break;
2220         case ISCSI_PARAM_FIRST_BURST:
2221                 sscanf(buf, "%d", &session->first_burst);
2222                 break;
2223         case ISCSI_PARAM_MAX_BURST:
2224                 sscanf(buf, "%d", &session->max_burst);
2225                 break;
2226         case ISCSI_PARAM_PDU_INORDER_EN:
2227                 sscanf(buf, "%d", &session->pdu_inorder_en);
2228                 break;
2229         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2230                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2231                 break;
2232         case ISCSI_PARAM_ERL:
2233                 sscanf(buf, "%d", &session->erl);
2234                 break;
2235         case ISCSI_PARAM_IFMARKER_EN:
2236                 sscanf(buf, "%d", &value);
2237                 BUG_ON(value);
2238                 break;
2239         case ISCSI_PARAM_OFMARKER_EN:
2240                 sscanf(buf, "%d", &value);
2241                 BUG_ON(value);
2242                 break;
2243         case ISCSI_PARAM_EXP_STATSN:
2244                 sscanf(buf, "%u", &conn->exp_statsn);
2245                 break;
2246         case ISCSI_PARAM_USERNAME:
2247                 kfree(session->username);
2248                 session->username = kstrdup(buf, GFP_KERNEL);
2249                 if (!session->username)
2250                         return -ENOMEM;
2251                 break;
2252         case ISCSI_PARAM_USERNAME_IN:
2253                 kfree(session->username_in);
2254                 session->username_in = kstrdup(buf, GFP_KERNEL);
2255                 if (!session->username_in)
2256                         return -ENOMEM;
2257                 break;
2258         case ISCSI_PARAM_PASSWORD:
2259                 kfree(session->password);
2260                 session->password = kstrdup(buf, GFP_KERNEL);
2261                 if (!session->password)
2262                         return -ENOMEM;
2263                 break;
2264         case ISCSI_PARAM_PASSWORD_IN:
2265                 kfree(session->password_in);
2266                 session->password_in = kstrdup(buf, GFP_KERNEL);
2267                 if (!session->password_in)
2268                         return -ENOMEM;
2269                 break;
2270         case ISCSI_PARAM_TARGET_NAME:
2271                 /* this should not change between logins */
2272                 if (session->targetname)
2273                         break;
2274
2275                 session->targetname = kstrdup(buf, GFP_KERNEL);
2276                 if (!session->targetname)
2277                         return -ENOMEM;
2278                 break;
2279         case ISCSI_PARAM_TPGT:
2280                 sscanf(buf, "%d", &session->tpgt);
2281                 break;
2282         case ISCSI_PARAM_PERSISTENT_PORT:
2283                 sscanf(buf, "%d", &conn->persistent_port);
2284                 break;
2285         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2286                 /*
2287                  * this is the address returned in discovery so it should
2288                  * not change between logins.
2289                  */
2290                 if (conn->persistent_address)
2291                         break;
2292
2293                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2294                 if (!conn->persistent_address)
2295                         return -ENOMEM;
2296                 break;
2297         default:
2298                 return -ENOSYS;
2299         }
2300
2301         return 0;
2302 }
2303 EXPORT_SYMBOL_GPL(iscsi_set_param);
2304
2305 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2306                             enum iscsi_param param, char *buf)
2307 {
2308         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2309         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2310         int len;
2311
2312         switch(param) {
2313         case ISCSI_PARAM_FAST_ABORT:
2314                 len = sprintf(buf, "%d\n", session->fast_abort);
2315                 break;
2316         case ISCSI_PARAM_ABORT_TMO:
2317                 len = sprintf(buf, "%d\n", session->abort_timeout);
2318                 break;
2319         case ISCSI_PARAM_LU_RESET_TMO:
2320                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2321                 break;
2322         case ISCSI_PARAM_INITIAL_R2T_EN:
2323                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2324                 break;
2325         case ISCSI_PARAM_MAX_R2T:
2326                 len = sprintf(buf, "%hu\n", session->max_r2t);
2327                 break;
2328         case ISCSI_PARAM_IMM_DATA_EN:
2329                 len = sprintf(buf, "%d\n", session->imm_data_en);
2330                 break;
2331         case ISCSI_PARAM_FIRST_BURST:
2332                 len = sprintf(buf, "%u\n", session->first_burst);
2333                 break;
2334         case ISCSI_PARAM_MAX_BURST:
2335                 len = sprintf(buf, "%u\n", session->max_burst);
2336                 break;
2337         case ISCSI_PARAM_PDU_INORDER_EN:
2338                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2339                 break;
2340         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2341                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2342                 break;
2343         case ISCSI_PARAM_ERL:
2344                 len = sprintf(buf, "%d\n", session->erl);
2345                 break;
2346         case ISCSI_PARAM_TARGET_NAME:
2347                 len = sprintf(buf, "%s\n", session->targetname);
2348                 break;
2349         case ISCSI_PARAM_TPGT:
2350                 len = sprintf(buf, "%d\n", session->tpgt);
2351                 break;
2352         case ISCSI_PARAM_USERNAME:
2353                 len = sprintf(buf, "%s\n", session->username);
2354                 break;
2355         case ISCSI_PARAM_USERNAME_IN:
2356                 len = sprintf(buf, "%s\n", session->username_in);
2357                 break;
2358         case ISCSI_PARAM_PASSWORD:
2359                 len = sprintf(buf, "%s\n", session->password);
2360                 break;
2361         case ISCSI_PARAM_PASSWORD_IN:
2362                 len = sprintf(buf, "%s\n", session->password_in);
2363                 break;
2364         default:
2365                 return -ENOSYS;
2366         }
2367
2368         return len;
2369 }
2370 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2371
2372 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2373                          enum iscsi_param param, char *buf)
2374 {
2375         struct iscsi_conn *conn = cls_conn->dd_data;
2376         int len;
2377
2378         switch(param) {
2379         case ISCSI_PARAM_PING_TMO:
2380                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2381                 break;
2382         case ISCSI_PARAM_RECV_TMO:
2383                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2384                 break;
2385         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2386                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2387                 break;
2388         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2389                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2390                 break;
2391         case ISCSI_PARAM_HDRDGST_EN:
2392                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2393                 break;
2394         case ISCSI_PARAM_DATADGST_EN:
2395                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2396                 break;
2397         case ISCSI_PARAM_IFMARKER_EN:
2398                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2399                 break;
2400         case ISCSI_PARAM_OFMARKER_EN:
2401                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2402                 break;
2403         case ISCSI_PARAM_EXP_STATSN:
2404                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2405                 break;
2406         case ISCSI_PARAM_PERSISTENT_PORT:
2407                 len = sprintf(buf, "%d\n", conn->persistent_port);
2408                 break;
2409         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2410                 len = sprintf(buf, "%s\n", conn->persistent_address);
2411                 break;
2412         default:
2413                 return -ENOSYS;
2414         }
2415
2416         return len;
2417 }
2418 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2419
2420 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2421                          char *buf)
2422 {
2423         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2424         int len;
2425
2426         switch (param) {
2427         case ISCSI_HOST_PARAM_NETDEV_NAME:
2428                 if (!session->netdev)
2429                         len = sprintf(buf, "%s\n", "default");
2430                 else
2431                         len = sprintf(buf, "%s\n", session->netdev);
2432                 break;
2433         case ISCSI_HOST_PARAM_HWADDRESS:
2434                 if (!session->hwaddress)
2435                         len = sprintf(buf, "%s\n", "default");
2436                 else
2437                         len = sprintf(buf, "%s\n", session->hwaddress);
2438                 break;
2439         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2440                 if (!session->initiatorname)
2441                         len = sprintf(buf, "%s\n", "unknown");
2442                 else
2443                         len = sprintf(buf, "%s\n", session->initiatorname);
2444                 break;
2445
2446         default:
2447                 return -ENOSYS;
2448         }
2449
2450         return len;
2451 }
2452 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2453
2454 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2455                          char *buf, int buflen)
2456 {
2457         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2458
2459         switch (param) {
2460         case ISCSI_HOST_PARAM_NETDEV_NAME:
2461                 if (!session->netdev)
2462                         session->netdev = kstrdup(buf, GFP_KERNEL);
2463                 break;
2464         case ISCSI_HOST_PARAM_HWADDRESS:
2465                 if (!session->hwaddress)
2466                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2467                 break;
2468         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2469                 if (!session->initiatorname)
2470                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2471                 break;
2472         default:
2473                 return -ENOSYS;
2474         }
2475
2476         return 0;
2477 }
2478 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2479
2480 MODULE_AUTHOR("Mike Christie");
2481 MODULE_DESCRIPTION("iSCSI library functions");
2482 MODULE_LICENSE("GPL");