Merge branch 'fixes' of git://git.linux-nfs.org/pub/linux/nfs-2.6
[linux-2.6.git] / 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/mutex.h>
26 #include <linux/kfifo.h>
27 #include <linux/delay.h>
28 #include <net/tcp.h>
29 #include <scsi/scsi_cmnd.h>
30 #include <scsi/scsi_device.h>
31 #include <scsi/scsi_eh.h>
32 #include <scsi/scsi_tcq.h>
33 #include <scsi/scsi_host.h>
34 #include <scsi/scsi.h>
35 #include <scsi/iscsi_proto.h>
36 #include <scsi/scsi_transport.h>
37 #include <scsi/scsi_transport_iscsi.h>
38 #include <scsi/libiscsi.h>
39
40 struct iscsi_session *
41 class_to_transport_session(struct iscsi_cls_session *cls_session)
42 {
43         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
44         return iscsi_hostdata(shost->hostdata);
45 }
46 EXPORT_SYMBOL_GPL(class_to_transport_session);
47
48 #define INVALID_SN_DELTA        0xffff
49
50 int
51 iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
52 {
53         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
54         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
55
56         if (max_cmdsn < exp_cmdsn -1 &&
57             max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
58                 return ISCSI_ERR_MAX_CMDSN;
59         if (max_cmdsn > session->max_cmdsn ||
60             max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
61                 session->max_cmdsn = max_cmdsn;
62         if (exp_cmdsn > session->exp_cmdsn ||
63             exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
64                 session->exp_cmdsn = exp_cmdsn;
65
66         return 0;
67 }
68 EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
69
70 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
71                                    struct iscsi_data *hdr,
72                                    int transport_data_cnt)
73 {
74         struct iscsi_conn *conn = ctask->conn;
75
76         memset(hdr, 0, sizeof(struct iscsi_data));
77         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
78         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
79         ctask->unsol_datasn++;
80         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
81         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
82
83         hdr->itt = ctask->hdr->itt;
84         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
85
86         hdr->offset = cpu_to_be32(ctask->total_length -
87                                   transport_data_cnt -
88                                   ctask->unsol_count);
89
90         if (ctask->unsol_count > conn->max_xmit_dlength) {
91                 hton24(hdr->dlength, conn->max_xmit_dlength);
92                 ctask->data_count = conn->max_xmit_dlength;
93                 hdr->flags = 0;
94         } else {
95                 hton24(hdr->dlength, ctask->unsol_count);
96                 ctask->data_count = ctask->unsol_count;
97                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
98         }
99 }
100 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
101
102 /**
103  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
104  * @ctask: iscsi cmd task
105  *
106  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
107  * fields like dlength or final based on how much data it sends
108  */
109 static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
110 {
111         struct iscsi_conn *conn = ctask->conn;
112         struct iscsi_session *session = conn->session;
113         struct iscsi_cmd *hdr = ctask->hdr;
114         struct scsi_cmnd *sc = ctask->sc;
115
116         hdr->opcode = ISCSI_OP_SCSI_CMD;
117         hdr->flags = ISCSI_ATTR_SIMPLE;
118         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
119         hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
120                          (session->age << ISCSI_AGE_SHIFT);
121         hdr->data_length = cpu_to_be32(sc->request_bufflen);
122         hdr->cmdsn = cpu_to_be32(session->cmdsn);
123         session->cmdsn++;
124         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
125         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
126         memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
127
128         if (sc->sc_data_direction == DMA_TO_DEVICE) {
129                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
130                 /*
131                  * Write counters:
132                  *
133                  *      imm_count       bytes to be sent right after
134                  *                      SCSI PDU Header
135                  *
136                  *      unsol_count     bytes(as Data-Out) to be sent
137                  *                      without R2T ack right after
138                  *                      immediate data
139                  *
140                  *      r2t_data_count  bytes to be sent via R2T ack's
141                  *
142                  *      pad_count       bytes to be sent as zero-padding
143                  */
144                 ctask->imm_count = 0;
145                 ctask->unsol_count = 0;
146                 ctask->unsol_datasn = 0;
147
148                 if (session->imm_data_en) {
149                         if (ctask->total_length >= session->first_burst)
150                                 ctask->imm_count = min(session->first_burst,
151                                                         conn->max_xmit_dlength);
152                         else
153                                 ctask->imm_count = min(ctask->total_length,
154                                                         conn->max_xmit_dlength);
155                         hton24(ctask->hdr->dlength, ctask->imm_count);
156                 } else
157                         zero_data(ctask->hdr->dlength);
158
159                 if (!session->initial_r2t_en)
160                         ctask->unsol_count = min(session->first_burst,
161                                 ctask->total_length) - ctask->imm_count;
162                 if (!ctask->unsol_count)
163                         /* No unsolicit Data-Out's */
164                         ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
165         } else {
166                 ctask->datasn = 0;
167                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
168                 zero_data(hdr->dlength);
169
170                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
171                         hdr->flags |= ISCSI_FLAG_CMD_READ;
172         }
173
174         conn->scsicmd_pdus_cnt++;
175 }
176 EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
177
178 /**
179  * iscsi_complete_command - return command back to scsi-ml
180  * @session: iscsi session
181  * @ctask: iscsi cmd task
182  *
183  * Must be called with session lock.
184  * This function returns the scsi command to scsi-ml and returns
185  * the cmd task to the pool of available cmd tasks.
186  */
187 static void iscsi_complete_command(struct iscsi_session *session,
188                                    struct iscsi_cmd_task *ctask)
189 {
190         struct scsi_cmnd *sc = ctask->sc;
191
192         ctask->sc = NULL;
193         list_del_init(&ctask->running);
194         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
195         sc->scsi_done(sc);
196 }
197
198 /**
199  * iscsi_cmd_rsp - SCSI Command Response processing
200  * @conn: iscsi connection
201  * @hdr: iscsi header
202  * @ctask: scsi command task
203  * @data: cmd data buffer
204  * @datalen: len of buffer
205  *
206  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
207  * then completes the command and task.
208  **/
209 static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
210                               struct iscsi_cmd_task *ctask, char *data,
211                               int datalen)
212 {
213         int rc;
214         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
215         struct iscsi_session *session = conn->session;
216         struct scsi_cmnd *sc = ctask->sc;
217
218         rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
219         if (rc) {
220                 sc->result = DID_ERROR << 16;
221                 goto out;
222         }
223
224         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
225
226         sc->result = (DID_OK << 16) | rhdr->cmd_status;
227
228         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
229                 sc->result = DID_ERROR << 16;
230                 goto out;
231         }
232
233         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
234                 int senselen;
235
236                 if (datalen < 2) {
237 invalid_datalen:
238                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
239                                "invalid data buffer size of %d\n", datalen);
240                         sc->result = DID_BAD_TARGET << 16;
241                         goto out;
242                 }
243
244                 senselen = (data[0] << 8) | data[1];
245                 if (datalen < senselen)
246                         goto invalid_datalen;
247
248                 memcpy(sc->sense_buffer, data + 2,
249                        min(senselen, SCSI_SENSE_BUFFERSIZE));
250                 debug_scsi("copied %d bytes of sense\n",
251                            min(senselen, SCSI_SENSE_BUFFERSIZE));
252         }
253
254         if (sc->sc_data_direction == DMA_TO_DEVICE)
255                 goto out;
256
257         if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
258                 int res_count = be32_to_cpu(rhdr->residual_count);
259
260                 if (res_count > 0 && res_count <= sc->request_bufflen)
261                         sc->resid = res_count;
262                 else
263                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
264         } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
265                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
266         else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
267                 sc->resid = be32_to_cpu(rhdr->residual_count);
268
269 out:
270         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
271                    (long)sc, sc->result, ctask->itt);
272         conn->scsirsp_pdus_cnt++;
273
274         iscsi_complete_command(conn->session, ctask);
275         return rc;
276 }
277
278 /**
279  * __iscsi_complete_pdu - complete pdu
280  * @conn: iscsi conn
281  * @hdr: iscsi header
282  * @data: data buffer
283  * @datalen: len of data buffer
284  *
285  * Completes pdu processing by freeing any resources allocated at
286  * queuecommand or send generic. session lock must be held and verify
287  * itt must have been called.
288  */
289 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
290                          char *data, int datalen)
291 {
292         struct iscsi_session *session = conn->session;
293         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
294         struct iscsi_cmd_task *ctask;
295         struct iscsi_mgmt_task *mtask;
296         uint32_t itt;
297
298         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
299                 itt = hdr->itt & ISCSI_ITT_MASK;
300         else
301                 itt = hdr->itt;
302
303         if (itt < session->cmds_max) {
304                 ctask = session->cmds[itt];
305
306                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
307                            opcode, conn->id, ctask->itt, datalen);
308
309                 switch(opcode) {
310                 case ISCSI_OP_SCSI_CMD_RSP:
311                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
312                         rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
313                                                 datalen);
314                         break;
315                 case ISCSI_OP_SCSI_DATA_IN:
316                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
317                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
318                                 conn->scsirsp_pdus_cnt++;
319                                 iscsi_complete_command(session, ctask);
320                         }
321                         break;
322                 case ISCSI_OP_R2T:
323                         /* LLD handles this for now */
324                         break;
325                 default:
326                         rc = ISCSI_ERR_BAD_OPCODE;
327                         break;
328                 }
329         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
330                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
331                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
332
333                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
334                            opcode, conn->id, mtask->itt, datalen);
335
336                 rc = iscsi_check_assign_cmdsn(session,
337                                               (struct iscsi_nopin*)hdr);
338                 if (rc)
339                         goto done;
340
341                 switch(opcode) {
342                 case ISCSI_OP_LOGOUT_RSP:
343                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
344                         /* fall through */
345                 case ISCSI_OP_LOGIN_RSP:
346                 case ISCSI_OP_TEXT_RSP:
347                         /*
348                          * login related PDU's exp_statsn is handled in
349                          * userspace
350                          */
351                         rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
352                         list_del(&mtask->running);
353                         if (conn->login_mtask != mtask)
354                                 __kfifo_put(session->mgmtpool.queue,
355                                             (void*)&mtask, sizeof(void*));
356                         break;
357                 case ISCSI_OP_SCSI_TMFUNC_RSP:
358                         if (datalen) {
359                                 rc = ISCSI_ERR_PROTO;
360                                 break;
361                         }
362
363                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
364                         conn->tmfrsp_pdus_cnt++;
365                         if (conn->tmabort_state == TMABORT_INITIAL) {
366                                 conn->tmabort_state =
367                                         ((struct iscsi_tm_rsp *)hdr)->
368                                         response == ISCSI_TMF_RSP_COMPLETE ?
369                                                 TMABORT_SUCCESS:TMABORT_FAILED;
370                                 /* unblock eh_abort() */
371                                 wake_up(&conn->ehwait);
372                         }
373                         break;
374                 case ISCSI_OP_NOOP_IN:
375                         if (hdr->ttt != ISCSI_RESERVED_TAG) {
376                                 rc = ISCSI_ERR_PROTO;
377                                 break;
378                         }
379                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
380
381                         rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
382                         list_del(&mtask->running);
383                         if (conn->login_mtask != mtask)
384                                 __kfifo_put(session->mgmtpool.queue,
385                                             (void*)&mtask, sizeof(void*));
386                         break;
387                 default:
388                         rc = ISCSI_ERR_BAD_OPCODE;
389                         break;
390                 }
391         } else if (itt == ISCSI_RESERVED_TAG) {
392                 switch(opcode) {
393                 case ISCSI_OP_NOOP_IN:
394                         if (!datalen) {
395                                 rc = iscsi_check_assign_cmdsn(session,
396                                                  (struct iscsi_nopin*)hdr);
397                                 if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
398                                         rc = iscsi_recv_pdu(conn->cls_conn,
399                                                             hdr, NULL, 0);
400                         } else
401                                 rc = ISCSI_ERR_PROTO;
402                         break;
403                 case ISCSI_OP_REJECT:
404                         /* we need sth like iscsi_reject_rsp()*/
405                 case ISCSI_OP_ASYNC_EVENT:
406                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
407                         /* we need sth like iscsi_async_event_rsp() */
408                         rc = ISCSI_ERR_BAD_OPCODE;
409                         break;
410                 default:
411                         rc = ISCSI_ERR_BAD_OPCODE;
412                         break;
413                 }
414         } else
415                 rc = ISCSI_ERR_BAD_ITT;
416
417 done:
418         return rc;
419 }
420 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
421
422 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
423                        char *data, int datalen)
424 {
425         int rc;
426
427         spin_lock(&conn->session->lock);
428         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
429         spin_unlock(&conn->session->lock);
430         return rc;
431 }
432 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
433
434 /* verify itt (itt encoding: age+cid+itt) */
435 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
436                      uint32_t *ret_itt)
437 {
438         struct iscsi_session *session = conn->session;
439         struct iscsi_cmd_task *ctask;
440         uint32_t itt;
441
442         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
443                 if ((hdr->itt & ISCSI_AGE_MASK) !=
444                     (session->age << ISCSI_AGE_SHIFT)) {
445                         printk(KERN_ERR "iscsi: received itt %x expected "
446                                 "session age (%x)\n", hdr->itt,
447                                 session->age & ISCSI_AGE_MASK);
448                         return ISCSI_ERR_BAD_ITT;
449                 }
450
451                 if ((hdr->itt & ISCSI_CID_MASK) !=
452                     (conn->id << ISCSI_CID_SHIFT)) {
453                         printk(KERN_ERR "iscsi: received itt %x, expected "
454                                 "CID (%x)\n", hdr->itt, conn->id);
455                         return ISCSI_ERR_BAD_ITT;
456                 }
457                 itt = hdr->itt & ISCSI_ITT_MASK;
458         } else
459                 itt = hdr->itt;
460
461         if (itt < session->cmds_max) {
462                 ctask = session->cmds[itt];
463
464                 if (!ctask->sc) {
465                         printk(KERN_INFO "iscsi: dropping ctask with "
466                                "itt 0x%x\n", ctask->itt);
467                         /* force drop */
468                         return ISCSI_ERR_NO_SCSI_CMD;
469                 }
470
471                 if (ctask->sc->SCp.phase != session->age) {
472                         printk(KERN_ERR "iscsi: ctask's session age %d, "
473                                 "expected %d\n", ctask->sc->SCp.phase,
474                                 session->age);
475                         return ISCSI_ERR_SESSION_FAILED;
476                 }
477         }
478
479         *ret_itt = itt;
480         return 0;
481 }
482 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
483
484 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
485 {
486         struct iscsi_session *session = conn->session;
487         unsigned long flags;
488
489         spin_lock_irqsave(&session->lock, flags);
490         if (session->state == ISCSI_STATE_FAILED) {
491                 spin_unlock_irqrestore(&session->lock, flags);
492                 return;
493         }
494
495         if (conn->stop_stage == 0)
496                 session->state = ISCSI_STATE_FAILED;
497         spin_unlock_irqrestore(&session->lock, flags);
498         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
499         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
500         iscsi_conn_error(conn->cls_conn, err);
501 }
502 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
503
504 /**
505  * iscsi_data_xmit - xmit any command into the scheduled connection
506  * @conn: iscsi connection
507  *
508  * Notes:
509  *      The function can return -EAGAIN in which case the caller must
510  *      re-schedule it again later or recover. '0' return code means
511  *      successful xmit.
512  **/
513 static int iscsi_data_xmit(struct iscsi_conn *conn)
514 {
515         struct iscsi_transport *tt;
516         int rc = 0;
517
518         if (unlikely(conn->suspend_tx)) {
519                 debug_scsi("conn %d Tx suspended!\n", conn->id);
520                 return -ENODATA;
521         }
522         tt = conn->session->tt;
523
524         /*
525          * Transmit in the following order:
526          *
527          * 1) un-finished xmit (ctask or mtask)
528          * 2) immediate control PDUs
529          * 3) write data
530          * 4) SCSI commands
531          * 5) non-immediate control PDUs
532          *
533          * No need to lock around __kfifo_get as long as
534          * there's one producer and one consumer.
535          */
536
537         BUG_ON(conn->ctask && conn->mtask);
538
539         if (conn->ctask) {
540                 rc = tt->xmit_cmd_task(conn, conn->ctask);
541                 if (rc)
542                         goto again;
543                 /* done with this in-progress ctask */
544                 conn->ctask = NULL;
545         }
546         if (conn->mtask) {
547                 rc = tt->xmit_mgmt_task(conn, conn->mtask);
548                 if (rc)
549                         goto again;
550                 /* done with this in-progress mtask */
551                 conn->mtask = NULL;
552         }
553
554         /* process immediate first */
555         if (unlikely(__kfifo_len(conn->immqueue))) {
556                 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
557                                    sizeof(void*))) {
558                         spin_lock_bh(&conn->session->lock);
559                         list_add_tail(&conn->mtask->running,
560                                       &conn->mgmt_run_list);
561                         spin_unlock_bh(&conn->session->lock);
562                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
563                         if (rc)
564                                 goto again;
565                 }
566                 /* done with this mtask */
567                 conn->mtask = NULL;
568         }
569
570         /* process command queue */
571         while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
572                            sizeof(void*))) {
573                 /*
574                  * iscsi tcp may readd the task to the xmitqueue to send
575                  * write data
576                  */
577                 spin_lock_bh(&conn->session->lock);
578                 if (list_empty(&conn->ctask->running))
579                         list_add_tail(&conn->ctask->running, &conn->run_list);
580                 spin_unlock_bh(&conn->session->lock);
581                 rc = tt->xmit_cmd_task(conn, conn->ctask);
582                 if (rc)
583                         goto again;
584         }
585         /* done with this ctask */
586         conn->ctask = NULL;
587
588         /* process the rest control plane PDUs, if any */
589         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
590                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
591                                    sizeof(void*))) {
592                         spin_lock_bh(&conn->session->lock);
593                         list_add_tail(&conn->mtask->running,
594                                       &conn->mgmt_run_list);
595                         spin_unlock_bh(&conn->session->lock);
596                         rc = tt->xmit_mgmt_task(conn, conn->mtask);
597                         if (rc)
598                                 goto again;
599                 }
600                 /* done with this mtask */
601                 conn->mtask = NULL;
602         }
603
604         return -ENODATA;
605
606 again:
607         if (unlikely(conn->suspend_tx))
608                 return -ENODATA;
609
610         return rc;
611 }
612
613 static void iscsi_xmitworker(void *data)
614 {
615         struct iscsi_conn *conn = data;
616         int rc;
617         /*
618          * serialize Xmit worker on a per-connection basis.
619          */
620         mutex_lock(&conn->xmitmutex);
621         do {
622                 rc = iscsi_data_xmit(conn);
623         } while (rc >= 0 || rc == -EAGAIN);
624         mutex_unlock(&conn->xmitmutex);
625 }
626
627 enum {
628         FAILURE_BAD_HOST = 1,
629         FAILURE_SESSION_FAILED,
630         FAILURE_SESSION_FREED,
631         FAILURE_WINDOW_CLOSED,
632         FAILURE_SESSION_TERMINATE,
633         FAILURE_SESSION_IN_RECOVERY,
634         FAILURE_SESSION_RECOVERY_TIMEOUT,
635 };
636
637 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
638 {
639         struct Scsi_Host *host;
640         int reason = 0;
641         struct iscsi_session *session;
642         struct iscsi_conn *conn;
643         struct iscsi_cmd_task *ctask = NULL;
644
645         sc->scsi_done = done;
646         sc->result = 0;
647
648         host = sc->device->host;
649         session = iscsi_hostdata(host->hostdata);
650
651         spin_lock(&session->lock);
652
653         /*
654          * ISCSI_STATE_FAILED is a temp. state. The recovery
655          * code will decide what is best to do with command queued
656          * during this time
657          */
658         if (session->state != ISCSI_STATE_LOGGED_IN &&
659             session->state != ISCSI_STATE_FAILED) {
660                 /*
661                  * to handle the race between when we set the recovery state
662                  * and block the session we requeue here (commands could
663                  * be entering our queuecommand while a block is starting
664                  * up because the block code is not locked)
665                  */
666                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
667                         reason = FAILURE_SESSION_IN_RECOVERY;
668                         goto reject;
669                 }
670
671                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
672                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
673                 else if (session->state == ISCSI_STATE_TERMINATE)
674                         reason = FAILURE_SESSION_TERMINATE;
675                 else
676                         reason = FAILURE_SESSION_FREED;
677                 goto fault;
678         }
679
680         /*
681          * Check for iSCSI window and take care of CmdSN wrap-around
682          */
683         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
684                 reason = FAILURE_WINDOW_CLOSED;
685                 goto reject;
686         }
687
688         conn = session->leadconn;
689
690         __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
691         sc->SCp.phase = session->age;
692         sc->SCp.ptr = (char *)ctask;
693
694         ctask->mtask = NULL;
695         ctask->conn = conn;
696         ctask->sc = sc;
697         INIT_LIST_HEAD(&ctask->running);
698         ctask->total_length = sc->request_bufflen;
699         iscsi_prep_scsi_cmd_pdu(ctask);
700
701         session->tt->init_cmd_task(ctask);
702
703         __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
704         debug_scsi(
705                "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
706                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
707                 conn->id, (long)sc, ctask->itt, sc->request_bufflen,
708                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
709         spin_unlock(&session->lock);
710
711         scsi_queue_work(host, &conn->xmitwork);
712         return 0;
713
714 reject:
715         spin_unlock(&session->lock);
716         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
717         return SCSI_MLQUEUE_HOST_BUSY;
718
719 fault:
720         spin_unlock(&session->lock);
721         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
722                sc->cmnd[0], reason);
723         sc->result = (DID_NO_CONNECT << 16);
724         sc->resid = sc->request_bufflen;
725         sc->scsi_done(sc);
726         return 0;
727 }
728 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
729
730 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
731 {
732         if (depth > ISCSI_MAX_CMD_PER_LUN)
733                 depth = ISCSI_MAX_CMD_PER_LUN;
734         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
735         return sdev->queue_depth;
736 }
737 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
738
739 static int
740 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
741                         char *data, uint32_t data_size)
742 {
743         struct iscsi_session *session = conn->session;
744         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
745         struct iscsi_mgmt_task *mtask;
746
747         spin_lock_bh(&session->lock);
748         if (session->state == ISCSI_STATE_TERMINATE) {
749                 spin_unlock_bh(&session->lock);
750                 return -EPERM;
751         }
752         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
753             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
754                 /*
755                  * Login and Text are sent serially, in
756                  * request-followed-by-response sequence.
757                  * Same mtask can be used. Same ITT must be used.
758                  * Note that login_mtask is preallocated at conn_create().
759                  */
760                 mtask = conn->login_mtask;
761         else {
762                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
763                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
764
765                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
766                 if (!__kfifo_get(session->mgmtpool.queue,
767                                  (void*)&mtask, sizeof(void*))) {
768                         spin_unlock_bh(&session->lock);
769                         return -ENOSPC;
770                 }
771         }
772
773         /*
774          * pre-format CmdSN for outgoing PDU.
775          */
776         if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
777                 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
778                            (session->age << ISCSI_AGE_SHIFT);
779                 nop->cmdsn = cpu_to_be32(session->cmdsn);
780                 if (conn->c_stage == ISCSI_CONN_STARTED &&
781                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
782                         session->cmdsn++;
783         } else
784                 /* do not advance CmdSN */
785                 nop->cmdsn = cpu_to_be32(session->cmdsn);
786
787         if (data_size) {
788                 memcpy(mtask->data, data, data_size);
789                 mtask->data_count = data_size;
790         } else
791                 mtask->data_count = 0;
792
793         INIT_LIST_HEAD(&mtask->running);
794         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
795         if (session->tt->init_mgmt_task)
796                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
797         spin_unlock_bh(&session->lock);
798
799         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
800                    hdr->opcode, hdr->itt, data_size);
801
802         /*
803          * since send_pdu() could be called at least from two contexts,
804          * we need to serialize __kfifo_put, so we don't have to take
805          * additional lock on fast data-path
806          */
807         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
808                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
809         else
810                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
811
812         scsi_queue_work(session->host, &conn->xmitwork);
813         return 0;
814 }
815
816 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
817                         char *data, uint32_t data_size)
818 {
819         struct iscsi_conn *conn = cls_conn->dd_data;
820         int rc;
821
822         mutex_lock(&conn->xmitmutex);
823         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
824         mutex_unlock(&conn->xmitmutex);
825
826         return rc;
827 }
828 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
829
830 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
831 {
832         struct iscsi_session *session = class_to_transport_session(cls_session);
833         struct iscsi_conn *conn = session->leadconn;
834
835         spin_lock_bh(&session->lock);
836         if (session->state != ISCSI_STATE_LOGGED_IN) {
837                 session->state = ISCSI_STATE_RECOVERY_FAILED;
838                 if (conn)
839                         wake_up(&conn->ehwait);
840         }
841         spin_unlock_bh(&session->lock);
842 }
843 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
844
845 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
846 {
847         struct Scsi_Host *host = sc->device->host;
848         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
849         struct iscsi_conn *conn = session->leadconn;
850         int fail_session = 0;
851
852         spin_lock_bh(&session->lock);
853         if (session->state == ISCSI_STATE_TERMINATE) {
854 failed:
855                 debug_scsi("failing host reset: session terminated "
856                            "[CID %d age %d]", conn->id, session->age);
857                 spin_unlock_bh(&session->lock);
858                 return FAILED;
859         }
860
861         if (sc->SCp.phase == session->age) {
862                 debug_scsi("failing connection CID %d due to SCSI host reset",
863                            conn->id);
864                 fail_session = 1;
865         }
866         spin_unlock_bh(&session->lock);
867
868         /*
869          * we drop the lock here but the leadconn cannot be destoyed while
870          * we are in the scsi eh
871          */
872         if (fail_session)
873                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
874
875         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
876         wait_event_interruptible(conn->ehwait,
877                                  session->state == ISCSI_STATE_TERMINATE ||
878                                  session->state == ISCSI_STATE_LOGGED_IN ||
879                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
880         if (signal_pending(current))
881                 flush_signals(current);
882
883         spin_lock_bh(&session->lock);
884         if (session->state == ISCSI_STATE_LOGGED_IN)
885                 printk(KERN_INFO "iscsi: host reset succeeded\n");
886         else
887                 goto failed;
888         spin_unlock_bh(&session->lock);
889
890         return SUCCESS;
891 }
892 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
893
894 static void iscsi_tmabort_timedout(unsigned long data)
895 {
896         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
897         struct iscsi_conn *conn = ctask->conn;
898         struct iscsi_session *session = conn->session;
899
900         spin_lock(&session->lock);
901         if (conn->tmabort_state == TMABORT_INITIAL) {
902                 conn->tmabort_state = TMABORT_TIMEDOUT;
903                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
904                         ctask->sc, ctask->itt);
905                 /* unblock eh_abort() */
906                 wake_up(&conn->ehwait);
907         }
908         spin_unlock(&session->lock);
909 }
910
911 /* must be called with the mutex lock */
912 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
913                                  struct iscsi_cmd_task *ctask)
914 {
915         struct iscsi_conn *conn = ctask->conn;
916         struct iscsi_session *session = conn->session;
917         struct iscsi_tm *hdr = &conn->tmhdr;
918         int rc;
919
920         /*
921          * ctask timed out but session is OK requests must be serialized.
922          */
923         memset(hdr, 0, sizeof(struct iscsi_tm));
924         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
925         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
926         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
927         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
928         hdr->rtt = ctask->hdr->itt;
929         hdr->refcmdsn = ctask->hdr->cmdsn;
930
931         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
932                                      NULL, 0);
933         if (rc) {
934                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
935                 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
936                 return rc;
937         }
938
939         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
940
941         spin_lock_bh(&session->lock);
942         ctask->mtask = (struct iscsi_mgmt_task *)
943                         session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
944                                         ISCSI_MGMT_ITT_OFFSET];
945
946         if (conn->tmabort_state == TMABORT_INITIAL) {
947                 conn->tmfcmd_pdus_cnt++;
948                 conn->tmabort_timer.expires = 10*HZ + jiffies;
949                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
950                 conn->tmabort_timer.data = (unsigned long)ctask;
951                 add_timer(&conn->tmabort_timer);
952                 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
953         }
954         spin_unlock_bh(&session->lock);
955         mutex_unlock(&conn->xmitmutex);
956
957         /*
958          * block eh thread until:
959          *
960          * 1) abort response
961          * 2) abort timeout
962          * 3) session is terminated or restarted or userspace has
963          * given up on recovery
964          */
965         wait_event_interruptible(conn->ehwait,
966                                  sc->SCp.phase != session->age ||
967                                  session->state != ISCSI_STATE_LOGGED_IN ||
968                                  conn->tmabort_state != TMABORT_INITIAL);
969         if (signal_pending(current))
970                 flush_signals(current);
971         del_timer_sync(&conn->tmabort_timer);
972
973         mutex_lock(&conn->xmitmutex);
974         return 0;
975 }
976
977 /*
978  * xmit mutex and session lock must be held
979  */
980 #define iscsi_remove_task(tasktype)                                     \
981 static struct iscsi_##tasktype *                                        \
982 iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt)               \
983 {                                                                       \
984         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);            \
985         struct iscsi_##tasktype *task;                                  \
986                                                                         \
987         debug_scsi("searching %d tasks\n", nr_tasks);                   \
988                                                                         \
989         for (i = 0; i < nr_tasks; i++) {                                \
990                 __kfifo_get(fifo, (void*)&task, sizeof(void*));         \
991                 debug_scsi("check task %u\n", task->itt);               \
992                                                                         \
993                 if (task->itt == itt) {                                 \
994                         debug_scsi("matched task\n");                   \
995                         return task;                                    \
996                 }                                                       \
997                                                                         \
998                 __kfifo_put(fifo, (void*)&task, sizeof(void*));         \
999         }                                                               \
1000         return NULL;                                                    \
1001 }
1002
1003 iscsi_remove_task(mgmt_task);
1004 iscsi_remove_task(cmd_task);
1005
1006 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1007 {
1008         struct iscsi_conn *conn = ctask->conn;
1009         struct iscsi_session *session = conn->session;
1010
1011         if (!ctask->mtask)
1012                 return -EINVAL;
1013
1014         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1015                 list_del(&ctask->mtask->running);
1016         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1017                     sizeof(void*));
1018         ctask->mtask = NULL;
1019         return 0;
1020 }
1021
1022 /*
1023  * session lock and xmitmutex must be held
1024  */
1025 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1026                          int err)
1027 {
1028         struct scsi_cmnd *sc;
1029
1030         conn->session->tt->cleanup_cmd_task(conn, ctask);
1031         iscsi_ctask_mtask_cleanup(ctask);
1032
1033         sc = ctask->sc;
1034         if (!sc)
1035                 return;
1036         sc->result = err;
1037         sc->resid = sc->request_bufflen;
1038         iscsi_complete_command(conn->session, ctask);
1039 }
1040
1041 int iscsi_eh_abort(struct scsi_cmnd *sc)
1042 {
1043         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1044         struct iscsi_conn *conn = ctask->conn;
1045         struct iscsi_session *session = conn->session;
1046         struct iscsi_cmd_task *pending_ctask;
1047         int rc;
1048
1049         conn->eh_abort_cnt++;
1050         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1051
1052         mutex_lock(&conn->xmitmutex);
1053         spin_lock_bh(&session->lock);
1054
1055         /*
1056          * If we are not logged in or we have started a new session
1057          * then let the host reset code handle this
1058          */
1059         if (session->state != ISCSI_STATE_LOGGED_IN ||
1060             sc->SCp.phase != session->age)
1061                 goto failed;
1062
1063         /* ctask completed before time out */
1064         if (!ctask->sc)
1065                 goto success;
1066
1067         /* what should we do here ? */
1068         if (conn->ctask == ctask) {
1069                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1070                        "Failing abort\n", sc, ctask->itt);
1071                 goto failed;
1072         }
1073
1074         /* check for the easy pending cmd abort */
1075         pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt);
1076         if (pending_ctask) {
1077                 /* iscsi_tcp queues write transfers on the xmitqueue */
1078                 if (list_empty(&pending_ctask->running)) {
1079                         debug_scsi("found pending task\n");
1080                         goto success;
1081                 } else
1082                         __kfifo_put(conn->xmitqueue, (void*)&pending_ctask,
1083                                     sizeof(void*));
1084         }
1085
1086         conn->tmabort_state = TMABORT_INITIAL;
1087
1088         spin_unlock_bh(&session->lock);
1089         rc = iscsi_exec_abort_task(sc, ctask);
1090         spin_lock_bh(&session->lock);
1091
1092         iscsi_ctask_mtask_cleanup(ctask);
1093         if (rc || sc->SCp.phase != session->age ||
1094             session->state != ISCSI_STATE_LOGGED_IN)
1095                 goto failed;
1096
1097         /* ctask completed before tmf abort response */
1098         if (!ctask->sc) {
1099                 debug_scsi("sc completed while abort in progress\n");
1100                 goto success;
1101         }
1102
1103         if (conn->tmabort_state != TMABORT_SUCCESS) {
1104                 spin_unlock_bh(&session->lock);
1105                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1106                 spin_lock_bh(&session->lock);
1107                 goto failed;
1108         }
1109
1110 success:
1111         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1112         spin_unlock_bh(&session->lock);
1113
1114         /*
1115          * clean up task if aborted. we have the xmitmutex so grab
1116          * the recv lock as a writer
1117          */
1118         write_lock_bh(conn->recv_lock);
1119         spin_lock(&session->lock);
1120         fail_command(conn, ctask, DID_ABORT << 16);
1121         spin_unlock(&session->lock);
1122         write_unlock_bh(conn->recv_lock);
1123
1124         mutex_unlock(&conn->xmitmutex);
1125         return SUCCESS;
1126
1127 failed:
1128         spin_unlock_bh(&session->lock);
1129         mutex_unlock(&conn->xmitmutex);
1130
1131         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1132         return FAILED;
1133 }
1134 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1135
1136 int
1137 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1138 {
1139         int i;
1140
1141         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1142         if (*items == NULL)
1143                 return -ENOMEM;
1144
1145         q->max = max;
1146         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1147         if (q->pool == NULL) {
1148                 kfree(*items);
1149                 return -ENOMEM;
1150         }
1151
1152         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1153                               GFP_KERNEL, NULL);
1154         if (q->queue == ERR_PTR(-ENOMEM)) {
1155                 kfree(q->pool);
1156                 kfree(*items);
1157                 return -ENOMEM;
1158         }
1159
1160         for (i = 0; i < max; i++) {
1161                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1162                 if (q->pool[i] == NULL) {
1163                         int j;
1164
1165                         for (j = 0; j < i; j++)
1166                                 kfree(q->pool[j]);
1167
1168                         kfifo_free(q->queue);
1169                         kfree(q->pool);
1170                         kfree(*items);
1171                         return -ENOMEM;
1172                 }
1173                 memset(q->pool[i], 0, item_size);
1174                 (*items)[i] = q->pool[i];
1175                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1176         }
1177         return 0;
1178 }
1179 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1180
1181 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1182 {
1183         int i;
1184
1185         for (i = 0; i < q->max; i++)
1186                 kfree(items[i]);
1187         kfree(q->pool);
1188         kfree(items);
1189 }
1190 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1191
1192 /*
1193  * iSCSI Session's hostdata organization:
1194  *
1195  *    *------------------* <== hostdata_session(host->hostdata)
1196  *    | ptr to class sess|
1197  *    |------------------| <== iscsi_hostdata(host->hostdata)
1198  *    | iscsi_session    |
1199  *    *------------------*
1200  */
1201
1202 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1203                                  _sz % sizeof(unsigned long))
1204
1205 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1206
1207 /**
1208  * iscsi_session_setup - create iscsi cls session and host and session
1209  * @scsit: scsi transport template
1210  * @iscsit: iscsi transport template
1211  * @initial_cmdsn: initial CmdSN
1212  * @hostno: host no allocated
1213  *
1214  * This can be used by software iscsi_transports that allocate
1215  * a session per scsi host.
1216  **/
1217 struct iscsi_cls_session *
1218 iscsi_session_setup(struct iscsi_transport *iscsit,
1219                     struct scsi_transport_template *scsit,
1220                     int cmd_task_size, int mgmt_task_size,
1221                     uint32_t initial_cmdsn, uint32_t *hostno)
1222 {
1223         struct Scsi_Host *shost;
1224         struct iscsi_session *session;
1225         struct iscsi_cls_session *cls_session;
1226         int cmd_i;
1227
1228         shost = scsi_host_alloc(iscsit->host_template,
1229                                 hostdata_privsize(sizeof(*session)));
1230         if (!shost)
1231                 return NULL;
1232
1233         shost->max_id = 1;
1234         shost->max_channel = 0;
1235         shost->max_lun = iscsit->max_lun;
1236         shost->max_cmd_len = iscsit->max_cmd_len;
1237         shost->transportt = scsit;
1238         shost->transportt->create_work_queue = 1;
1239         *hostno = shost->host_no;
1240
1241         session = iscsi_hostdata(shost->hostdata);
1242         memset(session, 0, sizeof(struct iscsi_session));
1243         session->host = shost;
1244         session->state = ISCSI_STATE_FREE;
1245         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1246         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1247         session->cmdsn = initial_cmdsn;
1248         session->exp_cmdsn = initial_cmdsn + 1;
1249         session->max_cmdsn = initial_cmdsn + 1;
1250         session->max_r2t = 1;
1251         session->tt = iscsit;
1252
1253         /* initialize SCSI PDU commands pool */
1254         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1255                             (void***)&session->cmds,
1256                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1257                 goto cmdpool_alloc_fail;
1258
1259         /* pre-format cmds pool with ITT */
1260         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1261                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1262
1263                 if (cmd_task_size)
1264                         ctask->dd_data = &ctask[1];
1265                 ctask->itt = cmd_i;
1266         }
1267
1268         spin_lock_init(&session->lock);
1269         INIT_LIST_HEAD(&session->connections);
1270
1271         /* initialize immediate command pool */
1272         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1273                            (void***)&session->mgmt_cmds,
1274                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1275                 goto mgmtpool_alloc_fail;
1276
1277
1278         /* pre-format immediate cmds pool with ITT */
1279         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1280                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1281
1282                 if (mgmt_task_size)
1283                         mtask->dd_data = &mtask[1];
1284                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1285         }
1286
1287         if (scsi_add_host(shost, NULL))
1288                 goto add_host_fail;
1289
1290         if (!try_module_get(iscsit->owner))
1291                 goto cls_session_fail;
1292
1293         cls_session = iscsi_create_session(shost, iscsit, 0);
1294         if (!cls_session)
1295                 goto module_put;
1296         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1297
1298         return cls_session;
1299
1300 module_put:
1301         module_put(iscsit->owner);
1302 cls_session_fail:
1303         scsi_remove_host(shost);
1304 add_host_fail:
1305         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1306 mgmtpool_alloc_fail:
1307         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1308 cmdpool_alloc_fail:
1309         scsi_host_put(shost);
1310         return NULL;
1311 }
1312 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1313
1314 /**
1315  * iscsi_session_teardown - destroy session, host, and cls_session
1316  * shost: scsi host
1317  *
1318  * This can be used by software iscsi_transports that allocate
1319  * a session per scsi host.
1320  **/
1321 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1322 {
1323         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1324         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1325
1326         scsi_remove_host(shost);
1327
1328         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1329         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1330
1331         iscsi_destroy_session(cls_session);
1332         scsi_host_put(shost);
1333         module_put(cls_session->transport->owner);
1334 }
1335 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1336
1337 /**
1338  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1339  * @cls_session: iscsi_cls_session
1340  * @conn_idx: cid
1341  **/
1342 struct iscsi_cls_conn *
1343 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1344 {
1345         struct iscsi_session *session = class_to_transport_session(cls_session);
1346         struct iscsi_conn *conn;
1347         struct iscsi_cls_conn *cls_conn;
1348         char *data;
1349
1350         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1351         if (!cls_conn)
1352                 return NULL;
1353         conn = cls_conn->dd_data;
1354         memset(conn, 0, sizeof(*conn));
1355
1356         conn->session = session;
1357         conn->cls_conn = cls_conn;
1358         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1359         conn->id = conn_idx;
1360         conn->exp_statsn = 0;
1361         conn->tmabort_state = TMABORT_INITIAL;
1362         INIT_LIST_HEAD(&conn->run_list);
1363         INIT_LIST_HEAD(&conn->mgmt_run_list);
1364
1365         /* initialize general xmit PDU commands queue */
1366         conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
1367                                         GFP_KERNEL, NULL);
1368         if (conn->xmitqueue == ERR_PTR(-ENOMEM))
1369                 goto xmitqueue_alloc_fail;
1370
1371         /* initialize general immediate & non-immediate PDU commands queue */
1372         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1373                                         GFP_KERNEL, NULL);
1374         if (conn->immqueue == ERR_PTR(-ENOMEM))
1375                 goto immqueue_alloc_fail;
1376
1377         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1378                                         GFP_KERNEL, NULL);
1379         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1380                 goto mgmtqueue_alloc_fail;
1381
1382         INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1383
1384         /* allocate login_mtask used for the login/text sequences */
1385         spin_lock_bh(&session->lock);
1386         if (!__kfifo_get(session->mgmtpool.queue,
1387                          (void*)&conn->login_mtask,
1388                          sizeof(void*))) {
1389                 spin_unlock_bh(&session->lock);
1390                 goto login_mtask_alloc_fail;
1391         }
1392         spin_unlock_bh(&session->lock);
1393
1394         data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
1395         if (!data)
1396                 goto login_mtask_data_alloc_fail;
1397         conn->login_mtask->data = data;
1398
1399         init_timer(&conn->tmabort_timer);
1400         mutex_init(&conn->xmitmutex);
1401         init_waitqueue_head(&conn->ehwait);
1402
1403         return cls_conn;
1404
1405 login_mtask_data_alloc_fail:
1406         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1407                     sizeof(void*));
1408 login_mtask_alloc_fail:
1409         kfifo_free(conn->mgmtqueue);
1410 mgmtqueue_alloc_fail:
1411         kfifo_free(conn->immqueue);
1412 immqueue_alloc_fail:
1413         kfifo_free(conn->xmitqueue);
1414 xmitqueue_alloc_fail:
1415         iscsi_destroy_conn(cls_conn);
1416         return NULL;
1417 }
1418 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1419
1420 /**
1421  * iscsi_conn_teardown - teardown iscsi connection
1422  * cls_conn: iscsi class connection
1423  *
1424  * TODO: we may need to make this into a two step process
1425  * like scsi-mls remove + put host
1426  */
1427 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1428 {
1429         struct iscsi_conn *conn = cls_conn->dd_data;
1430         struct iscsi_session *session = conn->session;
1431         unsigned long flags;
1432
1433         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1434         mutex_lock(&conn->xmitmutex);
1435         if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE) {
1436                 if (session->tt->suspend_conn_recv)
1437                         session->tt->suspend_conn_recv(conn);
1438
1439                 session->tt->terminate_conn(conn);
1440         }
1441
1442         spin_lock_bh(&session->lock);
1443         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1444         if (session->leadconn == conn) {
1445                 /*
1446                  * leading connection? then give up on recovery.
1447                  */
1448                 session->state = ISCSI_STATE_TERMINATE;
1449                 wake_up(&conn->ehwait);
1450         }
1451         spin_unlock_bh(&session->lock);
1452
1453         mutex_unlock(&conn->xmitmutex);
1454
1455         /*
1456          * Block until all in-progress commands for this connection
1457          * time out or fail.
1458          */
1459         for (;;) {
1460                 spin_lock_irqsave(session->host->host_lock, flags);
1461                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1462                         spin_unlock_irqrestore(session->host->host_lock, flags);
1463                         break;
1464                 }
1465                 spin_unlock_irqrestore(session->host->host_lock, flags);
1466                 msleep_interruptible(500);
1467                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1468                        "host_failed %d\n", session->host->host_busy,
1469                        session->host->host_failed);
1470                 /*
1471                  * force eh_abort() to unblock
1472                  */
1473                 wake_up(&conn->ehwait);
1474         }
1475
1476         spin_lock_bh(&session->lock);
1477         kfree(conn->login_mtask->data);
1478         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1479                     sizeof(void*));
1480         list_del(&conn->item);
1481         if (list_empty(&session->connections))
1482                 session->leadconn = NULL;
1483         if (session->leadconn && session->leadconn == conn)
1484                 session->leadconn = container_of(session->connections.next,
1485                         struct iscsi_conn, item);
1486
1487         if (session->leadconn == NULL)
1488                 /* no connections exits.. reset sequencing */
1489                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1490         spin_unlock_bh(&session->lock);
1491
1492         kfifo_free(conn->xmitqueue);
1493         kfifo_free(conn->immqueue);
1494         kfifo_free(conn->mgmtqueue);
1495
1496         iscsi_destroy_conn(cls_conn);
1497 }
1498 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1499
1500 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1501 {
1502         struct iscsi_conn *conn = cls_conn->dd_data;
1503         struct iscsi_session *session = conn->session;
1504
1505         if (session == NULL) {
1506                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1507                 return -EPERM;
1508         }
1509
1510         spin_lock_bh(&session->lock);
1511         conn->c_stage = ISCSI_CONN_STARTED;
1512         session->state = ISCSI_STATE_LOGGED_IN;
1513
1514         switch(conn->stop_stage) {
1515         case STOP_CONN_RECOVER:
1516                 /*
1517                  * unblock eh_abort() if it is blocked. re-try all
1518                  * commands after successful recovery
1519                  */
1520                 conn->stop_stage = 0;
1521                 conn->tmabort_state = TMABORT_INITIAL;
1522                 session->age++;
1523                 spin_unlock_bh(&session->lock);
1524
1525                 iscsi_unblock_session(session_to_cls(session));
1526                 wake_up(&conn->ehwait);
1527                 return 0;
1528         case STOP_CONN_TERM:
1529                 conn->stop_stage = 0;
1530                 break;
1531         default:
1532                 break;
1533         }
1534         spin_unlock_bh(&session->lock);
1535
1536         return 0;
1537 }
1538 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1539
1540 static void
1541 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1542 {
1543         struct iscsi_mgmt_task *mtask, *tmp;
1544
1545         /* handle pending */
1546         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1547                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1548                 if (mtask == conn->login_mtask)
1549                         continue;
1550                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1551                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1552                             sizeof(void*));
1553         }
1554
1555         /* handle running */
1556         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1557                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1558                 list_del(&mtask->running);
1559
1560                 if (mtask == conn->login_mtask)
1561                         continue;
1562                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1563                            sizeof(void*));
1564         }
1565
1566         conn->mtask = NULL;
1567 }
1568
1569 /* Fail commands. Mutex and session lock held and recv side suspended */
1570 static void fail_all_commands(struct iscsi_conn *conn)
1571 {
1572         struct iscsi_cmd_task *ctask, *tmp;
1573
1574         /* flush pending */
1575         while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) {
1576                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1577                            ctask->itt);
1578                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1579         }
1580
1581         /* fail all other running */
1582         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1583                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1584                            ctask->sc, ctask->itt);
1585                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1586         }
1587
1588         conn->ctask = NULL;
1589 }
1590
1591 static void iscsi_start_session_recovery(struct iscsi_session *session,
1592                                          struct iscsi_conn *conn, int flag)
1593 {
1594         int old_stop_stage;
1595
1596         spin_lock_bh(&session->lock);
1597         if (conn->stop_stage == STOP_CONN_TERM) {
1598                 spin_unlock_bh(&session->lock);
1599                 return;
1600         }
1601
1602         /*
1603          * When this is called for the in_login state, we only want to clean
1604          * up the login task and connection. We do not need to block and set
1605          * the recovery state again
1606          */
1607         if (flag == STOP_CONN_TERM)
1608                 session->state = ISCSI_STATE_TERMINATE;
1609         else if (conn->stop_stage != STOP_CONN_RECOVER)
1610                 session->state = ISCSI_STATE_IN_RECOVERY;
1611
1612         old_stop_stage = conn->stop_stage;
1613         conn->stop_stage = flag;
1614         conn->c_stage = ISCSI_CONN_STOPPED;
1615         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1616         spin_unlock_bh(&session->lock);
1617
1618         if (session->tt->suspend_conn_recv)
1619                 session->tt->suspend_conn_recv(conn);
1620
1621         mutex_lock(&conn->xmitmutex);
1622         /*
1623          * for connection level recovery we should not calculate
1624          * header digest. conn->hdr_size used for optimization
1625          * in hdr_extract() and will be re-negotiated at
1626          * set_param() time.
1627          */
1628         if (flag == STOP_CONN_RECOVER) {
1629                 conn->hdrdgst_en = 0;
1630                 conn->datadgst_en = 0;
1631                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1632                     old_stop_stage != STOP_CONN_RECOVER) {
1633                         debug_scsi("blocking session\n");
1634                         iscsi_block_session(session_to_cls(session));
1635                 }
1636         }
1637
1638         session->tt->terminate_conn(conn);
1639         /*
1640          * flush queues.
1641          */
1642         spin_lock_bh(&session->lock);
1643         fail_all_commands(conn);
1644         flush_control_queues(session, conn);
1645         spin_unlock_bh(&session->lock);
1646
1647         mutex_unlock(&conn->xmitmutex);
1648 }
1649
1650 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1651 {
1652         struct iscsi_conn *conn = cls_conn->dd_data;
1653         struct iscsi_session *session = conn->session;
1654
1655         switch (flag) {
1656         case STOP_CONN_RECOVER:
1657         case STOP_CONN_TERM:
1658                 iscsi_start_session_recovery(session, conn, flag);
1659                 break;
1660         default:
1661                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1662         }
1663 }
1664 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1665
1666 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1667                     struct iscsi_cls_conn *cls_conn, int is_leading)
1668 {
1669         struct iscsi_session *session = class_to_transport_session(cls_session);
1670         struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
1671
1672         /* lookup for existing connection */
1673         spin_lock_bh(&session->lock);
1674         list_for_each_entry(tmp, &session->connections, item) {
1675                 if (tmp == conn) {
1676                         if (conn->c_stage != ISCSI_CONN_STOPPED ||
1677                             conn->stop_stage == STOP_CONN_TERM) {
1678                                 printk(KERN_ERR "iscsi: can't bind "
1679                                        "non-stopped connection (%d:%d)\n",
1680                                        conn->c_stage, conn->stop_stage);
1681                                 spin_unlock_bh(&session->lock);
1682                                 return -EIO;
1683                         }
1684                         break;
1685                 }
1686         }
1687         if (tmp != conn) {
1688                 /* bind new iSCSI connection to session */
1689                 conn->session = session;
1690                 list_add(&conn->item, &session->connections);
1691         }
1692         spin_unlock_bh(&session->lock);
1693
1694         if (is_leading)
1695                 session->leadconn = conn;
1696
1697         /*
1698          * Unblock xmitworker(), Login Phase will pass through.
1699          */
1700         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1701         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1702         return 0;
1703 }
1704 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1705
1706
1707 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1708                     enum iscsi_param param, char *buf, int buflen)
1709 {
1710         struct iscsi_conn *conn = cls_conn->dd_data;
1711         struct iscsi_session *session = conn->session;
1712         uint32_t value;
1713
1714         switch(param) {
1715         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1716                 sscanf(buf, "%d", &conn->max_recv_dlength);
1717                 break;
1718         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1719                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1720                 break;
1721         case ISCSI_PARAM_HDRDGST_EN:
1722                 sscanf(buf, "%d", &conn->hdrdgst_en);
1723                 break;
1724         case ISCSI_PARAM_DATADGST_EN:
1725                 sscanf(buf, "%d", &conn->datadgst_en);
1726                 break;
1727         case ISCSI_PARAM_INITIAL_R2T_EN:
1728                 sscanf(buf, "%d", &session->initial_r2t_en);
1729                 break;
1730         case ISCSI_PARAM_MAX_R2T:
1731                 sscanf(buf, "%d", &session->max_r2t);
1732                 break;
1733         case ISCSI_PARAM_IMM_DATA_EN:
1734                 sscanf(buf, "%d", &session->imm_data_en);
1735                 break;
1736         case ISCSI_PARAM_FIRST_BURST:
1737                 sscanf(buf, "%d", &session->first_burst);
1738                 break;
1739         case ISCSI_PARAM_MAX_BURST:
1740                 sscanf(buf, "%d", &session->max_burst);
1741                 break;
1742         case ISCSI_PARAM_PDU_INORDER_EN:
1743                 sscanf(buf, "%d", &session->pdu_inorder_en);
1744                 break;
1745         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1746                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1747                 break;
1748         case ISCSI_PARAM_ERL:
1749                 sscanf(buf, "%d", &session->erl);
1750                 break;
1751         case ISCSI_PARAM_IFMARKER_EN:
1752                 sscanf(buf, "%d", &value);
1753                 BUG_ON(value);
1754                 break;
1755         case ISCSI_PARAM_OFMARKER_EN:
1756                 sscanf(buf, "%d", &value);
1757                 BUG_ON(value);
1758                 break;
1759         case ISCSI_PARAM_EXP_STATSN:
1760                 sscanf(buf, "%u", &conn->exp_statsn);
1761                 break;
1762         case ISCSI_PARAM_TARGET_NAME:
1763                 /* this should not change between logins */
1764                 if (session->targetname)
1765                         break;
1766
1767                 session->targetname = kstrdup(buf, GFP_KERNEL);
1768                 if (!session->targetname)
1769                         return -ENOMEM;
1770                 break;
1771         case ISCSI_PARAM_TPGT:
1772                 sscanf(buf, "%d", &session->tpgt);
1773                 break;
1774         case ISCSI_PARAM_PERSISTENT_PORT:
1775                 sscanf(buf, "%d", &conn->persistent_port);
1776                 break;
1777         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1778                 /*
1779                  * this is the address returned in discovery so it should
1780                  * not change between logins.
1781                  */
1782                 if (conn->persistent_address)
1783                         break;
1784
1785                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1786                 if (!conn->persistent_address)
1787                         return -ENOMEM;
1788                 break;
1789         default:
1790                 return -ENOSYS;
1791         }
1792
1793         return 0;
1794 }
1795 EXPORT_SYMBOL_GPL(iscsi_set_param);
1796
1797 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1798                             enum iscsi_param param, char *buf)
1799 {
1800         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1801         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1802         int len;
1803
1804         switch(param) {
1805         case ISCSI_PARAM_INITIAL_R2T_EN:
1806                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1807                 break;
1808         case ISCSI_PARAM_MAX_R2T:
1809                 len = sprintf(buf, "%hu\n", session->max_r2t);
1810                 break;
1811         case ISCSI_PARAM_IMM_DATA_EN:
1812                 len = sprintf(buf, "%d\n", session->imm_data_en);
1813                 break;
1814         case ISCSI_PARAM_FIRST_BURST:
1815                 len = sprintf(buf, "%u\n", session->first_burst);
1816                 break;
1817         case ISCSI_PARAM_MAX_BURST:
1818                 len = sprintf(buf, "%u\n", session->max_burst);
1819                 break;
1820         case ISCSI_PARAM_PDU_INORDER_EN:
1821                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1822                 break;
1823         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1824                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1825                 break;
1826         case ISCSI_PARAM_ERL:
1827                 len = sprintf(buf, "%d\n", session->erl);
1828                 break;
1829         case ISCSI_PARAM_TARGET_NAME:
1830                 len = sprintf(buf, "%s\n", session->targetname);
1831                 break;
1832         case ISCSI_PARAM_TPGT:
1833                 len = sprintf(buf, "%d\n", session->tpgt);
1834                 break;
1835         default:
1836                 return -ENOSYS;
1837         }
1838
1839         return len;
1840 }
1841 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1842
1843 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1844                          enum iscsi_param param, char *buf)
1845 {
1846         struct iscsi_conn *conn = cls_conn->dd_data;
1847         int len;
1848
1849         switch(param) {
1850         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1851                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1852                 break;
1853         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1854                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1855                 break;
1856         case ISCSI_PARAM_HDRDGST_EN:
1857                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1858                 break;
1859         case ISCSI_PARAM_DATADGST_EN:
1860                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1861                 break;
1862         case ISCSI_PARAM_IFMARKER_EN:
1863                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1864                 break;
1865         case ISCSI_PARAM_OFMARKER_EN:
1866                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1867                 break;
1868         case ISCSI_PARAM_EXP_STATSN:
1869                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1870                 break;
1871         case ISCSI_PARAM_PERSISTENT_PORT:
1872                 len = sprintf(buf, "%d\n", conn->persistent_port);
1873                 break;
1874         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1875                 len = sprintf(buf, "%s\n", conn->persistent_address);
1876                 break;
1877         default:
1878                 return -ENOSYS;
1879         }
1880
1881         return len;
1882 }
1883 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1884
1885 MODULE_AUTHOR("Mike Christie");
1886 MODULE_DESCRIPTION("iSCSI library functions");
1887 MODULE_LICENSE("GPL");