0a9c64e9ce8b57fd712ccb69e5eeb3ee86ec5c0a
[safe/jmp/linux-2.6] / 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 <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 #define INVALID_SN_DELTA        0xffff
50
51 int
52 iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
53 {
54         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
55         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
56
57         if (max_cmdsn < exp_cmdsn -1 &&
58             max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
59                 return ISCSI_ERR_MAX_CMDSN;
60         if (max_cmdsn > session->max_cmdsn ||
61             max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
62                 session->max_cmdsn = max_cmdsn;
63         if (exp_cmdsn > session->exp_cmdsn ||
64             exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
65                 session->exp_cmdsn = exp_cmdsn;
66
67         return 0;
68 }
69 EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
70
71 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
72                                    struct iscsi_data *hdr)
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         hdr->offset = cpu_to_be32(ctask->unsol_offset);
86
87         if (ctask->unsol_count > conn->max_xmit_dlength) {
88                 hton24(hdr->dlength, conn->max_xmit_dlength);
89                 ctask->data_count = conn->max_xmit_dlength;
90                 ctask->unsol_offset += ctask->data_count;
91                 hdr->flags = 0;
92         } else {
93                 hton24(hdr->dlength, ctask->unsol_count);
94                 ctask->data_count = ctask->unsol_count;
95                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
96         }
97 }
98 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
99
100 /**
101  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
102  * @ctask: iscsi cmd task
103  *
104  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
105  * fields like dlength or final based on how much data it sends
106  */
107 static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
108 {
109         struct iscsi_conn *conn = ctask->conn;
110         struct iscsi_session *session = conn->session;
111         struct iscsi_cmd *hdr = ctask->hdr;
112         struct scsi_cmnd *sc = ctask->sc;
113
114         hdr->opcode = ISCSI_OP_SCSI_CMD;
115         hdr->flags = ISCSI_ATTR_SIMPLE;
116         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
117         hdr->itt = build_itt(ctask->itt, conn->id, session->age);
118         hdr->data_length = cpu_to_be32(sc->request_bufflen);
119         hdr->cmdsn = cpu_to_be32(session->cmdsn);
120         session->cmdsn++;
121         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
122         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
123         if (sc->cmd_len < MAX_COMMAND_SIZE)
124                 memset(&hdr->cdb[sc->cmd_len], 0,
125                         MAX_COMMAND_SIZE - sc->cmd_len);
126
127         ctask->data_count = 0;
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_offset = 0;
147                 ctask->unsol_datasn = 0;
148
149                 if (session->imm_data_en) {
150                         if (sc->request_bufflen >= session->first_burst)
151                                 ctask->imm_count = min(session->first_burst,
152                                                         conn->max_xmit_dlength);
153                         else
154                                 ctask->imm_count = min(sc->request_bufflen,
155                                                         conn->max_xmit_dlength);
156                         hton24(ctask->hdr->dlength, ctask->imm_count);
157                 } else
158                         zero_data(ctask->hdr->dlength);
159
160                 if (!session->initial_r2t_en) {
161                         ctask->unsol_count = min((session->first_burst),
162                                 (sc->request_bufflen)) - ctask->imm_count;
163                         ctask->unsol_offset = ctask->imm_count;
164                 }
165
166                 if (!ctask->unsol_count)
167                         /* No unsolicit Data-Out's */
168                         ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
169         } else {
170                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
171                 zero_data(hdr->dlength);
172
173                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
174                         hdr->flags |= ISCSI_FLAG_CMD_READ;
175         }
176
177         conn->scsicmd_pdus_cnt++;
178 }
179 EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
180
181 /**
182  * iscsi_complete_command - return command back to scsi-ml
183  * @ctask: iscsi cmd task
184  *
185  * Must be called with session lock.
186  * This function returns the scsi command to scsi-ml and returns
187  * the cmd task to the pool of available cmd tasks.
188  */
189 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
190 {
191         struct iscsi_session *session = ctask->conn->session;
192         struct scsi_cmnd *sc = ctask->sc;
193
194         ctask->state = ISCSI_TASK_COMPLETED;
195         ctask->sc = NULL;
196         /* SCSI eh reuses commands to verify us */
197         sc->SCp.ptr = NULL;
198         list_del_init(&ctask->running);
199         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
200         sc->scsi_done(sc);
201 }
202
203 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
204 {
205         atomic_inc(&ctask->refcount);
206 }
207
208 static void iscsi_get_ctask(struct iscsi_cmd_task *ctask)
209 {
210         spin_lock_bh(&ctask->conn->session->lock);
211         __iscsi_get_ctask(ctask);
212         spin_unlock_bh(&ctask->conn->session->lock);
213 }
214
215 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
216 {
217         if (atomic_dec_and_test(&ctask->refcount))
218                 iscsi_complete_command(ctask);
219 }
220
221 static void iscsi_put_ctask(struct iscsi_cmd_task *ctask)
222 {
223         spin_lock_bh(&ctask->conn->session->lock);
224         __iscsi_put_ctask(ctask);
225         spin_unlock_bh(&ctask->conn->session->lock);
226 }
227
228 /**
229  * iscsi_cmd_rsp - SCSI Command Response processing
230  * @conn: iscsi connection
231  * @hdr: iscsi header
232  * @ctask: scsi command task
233  * @data: cmd data buffer
234  * @datalen: len of buffer
235  *
236  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
237  * then completes the command and task.
238  **/
239 static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
240                               struct iscsi_cmd_task *ctask, char *data,
241                               int datalen)
242 {
243         int rc;
244         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
245         struct iscsi_session *session = conn->session;
246         struct scsi_cmnd *sc = ctask->sc;
247
248         rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
249         if (rc) {
250                 sc->result = DID_ERROR << 16;
251                 goto out;
252         }
253
254         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
255
256         sc->result = (DID_OK << 16) | rhdr->cmd_status;
257
258         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
259                 sc->result = DID_ERROR << 16;
260                 goto out;
261         }
262
263         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
264                 uint16_t senselen;
265
266                 if (datalen < 2) {
267 invalid_datalen:
268                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
269                                "invalid data buffer size of %d\n", datalen);
270                         sc->result = DID_BAD_TARGET << 16;
271                         goto out;
272                 }
273
274                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
275                 if (datalen < senselen)
276                         goto invalid_datalen;
277
278                 memcpy(sc->sense_buffer, data + 2,
279                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
280                 debug_scsi("copied %d bytes of sense\n",
281                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
282         }
283
284         if (sc->sc_data_direction == DMA_TO_DEVICE)
285                 goto out;
286
287         if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
288                 int res_count = be32_to_cpu(rhdr->residual_count);
289
290                 if (res_count > 0 && res_count <= sc->request_bufflen)
291                         sc->resid = res_count;
292                 else
293                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
294         } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
295                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
296         else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
297                 sc->resid = be32_to_cpu(rhdr->residual_count);
298
299 out:
300         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
301                    (long)sc, sc->result, ctask->itt);
302         conn->scsirsp_pdus_cnt++;
303
304         __iscsi_put_ctask(ctask);
305         return rc;
306 }
307
308 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
309 {
310         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
311
312         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
313         conn->tmfrsp_pdus_cnt++;
314
315         if (conn->tmabort_state != TMABORT_INITIAL)
316                 return;
317
318         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
319                 conn->tmabort_state = TMABORT_SUCCESS;
320         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
321                 conn->tmabort_state = TMABORT_NOT_FOUND;
322         else
323                 conn->tmabort_state = TMABORT_FAILED;
324         wake_up(&conn->ehwait);
325 }
326
327 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
328                                char *data, int datalen)
329 {
330         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
331         struct iscsi_hdr rejected_pdu;
332         uint32_t itt;
333
334         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
335
336         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
337                 if (ntoh24(reject->dlength) > datalen)
338                         return ISCSI_ERR_PROTO;
339
340                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
341                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
342                         itt = get_itt(rejected_pdu.itt);
343                         printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
344                                 "due to DataDigest error.\n", itt,
345                                 rejected_pdu.opcode);
346                 }
347         }
348         return 0;
349 }
350
351 /**
352  * __iscsi_complete_pdu - complete pdu
353  * @conn: iscsi conn
354  * @hdr: iscsi header
355  * @data: data buffer
356  * @datalen: len of data buffer
357  *
358  * Completes pdu processing by freeing any resources allocated at
359  * queuecommand or send generic. session lock must be held and verify
360  * itt must have been called.
361  */
362 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
363                          char *data, int datalen)
364 {
365         struct iscsi_session *session = conn->session;
366         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
367         struct iscsi_cmd_task *ctask;
368         struct iscsi_mgmt_task *mtask;
369         uint32_t itt;
370
371         if (hdr->itt != RESERVED_ITT)
372                 itt = get_itt(hdr->itt);
373         else
374                 itt = ~0U;
375
376         if (itt < session->cmds_max) {
377                 ctask = session->cmds[itt];
378
379                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
380                            opcode, conn->id, ctask->itt, datalen);
381
382                 switch(opcode) {
383                 case ISCSI_OP_SCSI_CMD_RSP:
384                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
385                         rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
386                                                 datalen);
387                         break;
388                 case ISCSI_OP_SCSI_DATA_IN:
389                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
390                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
391                                 conn->scsirsp_pdus_cnt++;
392                                 __iscsi_put_ctask(ctask);
393                         }
394                         break;
395                 case ISCSI_OP_R2T:
396                         /* LLD handles this for now */
397                         break;
398                 default:
399                         rc = ISCSI_ERR_BAD_OPCODE;
400                         break;
401                 }
402         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
403                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
404                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
405
406                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
407                            opcode, conn->id, mtask->itt, datalen);
408
409                 rc = iscsi_check_assign_cmdsn(session,
410                                               (struct iscsi_nopin*)hdr);
411                 if (rc)
412                         goto done;
413
414                 switch(opcode) {
415                 case ISCSI_OP_LOGOUT_RSP:
416                         if (datalen) {
417                                 rc = ISCSI_ERR_PROTO;
418                                 break;
419                         }
420                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
421                         /* fall through */
422                 case ISCSI_OP_LOGIN_RSP:
423                 case ISCSI_OP_TEXT_RSP:
424                         /*
425                          * login related PDU's exp_statsn is handled in
426                          * userspace
427                          */
428                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
429                                 rc = ISCSI_ERR_CONN_FAILED;
430                         list_del(&mtask->running);
431                         if (conn->login_mtask != mtask)
432                                 __kfifo_put(session->mgmtpool.queue,
433                                             (void*)&mtask, sizeof(void*));
434                         break;
435                 case ISCSI_OP_SCSI_TMFUNC_RSP:
436                         if (datalen) {
437                                 rc = ISCSI_ERR_PROTO;
438                                 break;
439                         }
440
441                         iscsi_tmf_rsp(conn, hdr);
442                         break;
443                 case ISCSI_OP_NOOP_IN:
444                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
445                                 rc = ISCSI_ERR_PROTO;
446                                 break;
447                         }
448                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
449
450                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
451                                 rc = ISCSI_ERR_CONN_FAILED;
452                         list_del(&mtask->running);
453                         if (conn->login_mtask != mtask)
454                                 __kfifo_put(session->mgmtpool.queue,
455                                             (void*)&mtask, sizeof(void*));
456                         break;
457                 default:
458                         rc = ISCSI_ERR_BAD_OPCODE;
459                         break;
460                 }
461         } else if (itt == ~0U) {
462                 rc = iscsi_check_assign_cmdsn(session,
463                                              (struct iscsi_nopin*)hdr);
464                 if (rc)
465                         goto done;
466
467                 switch(opcode) {
468                 case ISCSI_OP_NOOP_IN:
469                         if (datalen) {
470                                 rc = ISCSI_ERR_PROTO;
471                                 break;
472                         }
473
474                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
475                                 break;
476
477                         if (iscsi_recv_pdu(conn->cls_conn, hdr, NULL, 0))
478                                 rc = ISCSI_ERR_CONN_FAILED;
479                         break;
480                 case ISCSI_OP_REJECT:
481                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
482                         break;
483                 case ISCSI_OP_ASYNC_EVENT:
484                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
485                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
486                                 rc = ISCSI_ERR_CONN_FAILED;
487                         break;
488                 default:
489                         rc = ISCSI_ERR_BAD_OPCODE;
490                         break;
491                 }
492         } else
493                 rc = ISCSI_ERR_BAD_ITT;
494
495 done:
496         return rc;
497 }
498 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
499
500 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
501                        char *data, int datalen)
502 {
503         int rc;
504
505         spin_lock(&conn->session->lock);
506         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
507         spin_unlock(&conn->session->lock);
508         return rc;
509 }
510 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
511
512 /* verify itt (itt encoding: age+cid+itt) */
513 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
514                      uint32_t *ret_itt)
515 {
516         struct iscsi_session *session = conn->session;
517         struct iscsi_cmd_task *ctask;
518         uint32_t itt;
519
520         if (hdr->itt != RESERVED_ITT) {
521                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
522                     (session->age << ISCSI_AGE_SHIFT)) {
523                         printk(KERN_ERR "iscsi: received itt %x expected "
524                                 "session age (%x)\n", (__force u32)hdr->itt,
525                                 session->age & ISCSI_AGE_MASK);
526                         return ISCSI_ERR_BAD_ITT;
527                 }
528
529                 if (((__force u32)hdr->itt & ISCSI_CID_MASK) !=
530                     (conn->id << ISCSI_CID_SHIFT)) {
531                         printk(KERN_ERR "iscsi: received itt %x, expected "
532                                 "CID (%x)\n", (__force u32)hdr->itt, conn->id);
533                         return ISCSI_ERR_BAD_ITT;
534                 }
535                 itt = get_itt(hdr->itt);
536         } else
537                 itt = ~0U;
538
539         if (itt < session->cmds_max) {
540                 ctask = session->cmds[itt];
541
542                 if (!ctask->sc) {
543                         printk(KERN_INFO "iscsi: dropping ctask with "
544                                "itt 0x%x\n", ctask->itt);
545                         /* force drop */
546                         return ISCSI_ERR_NO_SCSI_CMD;
547                 }
548
549                 if (ctask->sc->SCp.phase != session->age) {
550                         printk(KERN_ERR "iscsi: ctask's session age %d, "
551                                 "expected %d\n", ctask->sc->SCp.phase,
552                                 session->age);
553                         return ISCSI_ERR_SESSION_FAILED;
554                 }
555         }
556
557         *ret_itt = itt;
558         return 0;
559 }
560 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
561
562 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
563 {
564         struct iscsi_session *session = conn->session;
565         unsigned long flags;
566
567         spin_lock_irqsave(&session->lock, flags);
568         if (session->state == ISCSI_STATE_FAILED) {
569                 spin_unlock_irqrestore(&session->lock, flags);
570                 return;
571         }
572
573         if (conn->stop_stage == 0)
574                 session->state = ISCSI_STATE_FAILED;
575         spin_unlock_irqrestore(&session->lock, flags);
576         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
577         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
578         iscsi_conn_error(conn->cls_conn, err);
579 }
580 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
581
582 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
583 {
584         struct iscsi_hdr *hdr = conn->mtask->hdr;
585         int rc, was_logout = 0;
586
587         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT) {
588                 conn->session->state = ISCSI_STATE_IN_RECOVERY;
589                 iscsi_block_session(session_to_cls(conn->session));
590                 was_logout = 1;
591         }
592         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
593         if (rc)
594                 return rc;
595
596         /* done with this in-progress mtask */
597         conn->mtask = NULL;
598
599         if (was_logout) {
600                 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
601                 return -ENODATA;
602         }
603         return 0;
604 }
605
606 /**
607  * iscsi_data_xmit - xmit any command into the scheduled connection
608  * @conn: iscsi connection
609  *
610  * Notes:
611  *      The function can return -EAGAIN in which case the caller must
612  *      re-schedule it again later or recover. '0' return code means
613  *      successful xmit.
614  **/
615 static int iscsi_data_xmit(struct iscsi_conn *conn)
616 {
617         struct iscsi_transport *tt;
618         int rc = 0;
619
620         if (unlikely(conn->suspend_tx)) {
621                 debug_scsi("conn %d Tx suspended!\n", conn->id);
622                 return -ENODATA;
623         }
624         tt = conn->session->tt;
625
626         /*
627          * Transmit in the following order:
628          *
629          * 1) un-finished xmit (ctask or mtask)
630          * 2) immediate control PDUs
631          * 3) write data
632          * 4) SCSI commands
633          * 5) non-immediate control PDUs
634          *
635          * No need to lock around __kfifo_get as long as
636          * there's one producer and one consumer.
637          */
638
639         BUG_ON(conn->ctask && conn->mtask);
640
641         if (conn->ctask) {
642                 iscsi_get_ctask(conn->ctask);
643                 rc = tt->xmit_cmd_task(conn, conn->ctask);
644                 iscsi_put_ctask(conn->ctask);
645                 if (rc)
646                         goto again;
647                 /* done with this in-progress ctask */
648                 conn->ctask = NULL;
649         }
650         if (conn->mtask) {
651                 rc = iscsi_xmit_mtask(conn);
652                 if (rc)
653                         goto again;
654         }
655
656         /* process immediate first */
657         if (unlikely(__kfifo_len(conn->immqueue))) {
658                 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
659                                    sizeof(void*))) {
660                         spin_lock_bh(&conn->session->lock);
661                         list_add_tail(&conn->mtask->running,
662                                       &conn->mgmt_run_list);
663                         spin_unlock_bh(&conn->session->lock);
664                         rc = iscsi_xmit_mtask(conn);
665                         if (rc)
666                                 goto again;
667                 }
668         }
669
670         /* process command queue */
671         spin_lock_bh(&conn->session->lock);
672         while (!list_empty(&conn->xmitqueue)) {
673                 /*
674                  * iscsi tcp may readd the task to the xmitqueue to send
675                  * write data
676                  */
677                 conn->ctask = list_entry(conn->xmitqueue.next,
678                                          struct iscsi_cmd_task, running);
679                 conn->ctask->state = ISCSI_TASK_RUNNING;
680                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
681                 __iscsi_get_ctask(conn->ctask);
682                 spin_unlock_bh(&conn->session->lock);
683
684                 rc = tt->xmit_cmd_task(conn, conn->ctask);
685
686                 spin_lock_bh(&conn->session->lock);
687                 __iscsi_put_ctask(conn->ctask);
688                 if (rc) {
689                         spin_unlock_bh(&conn->session->lock);
690                         goto again;
691                 }
692         }
693         spin_unlock_bh(&conn->session->lock);
694         /* done with this ctask */
695         conn->ctask = NULL;
696
697         /* process the rest control plane PDUs, if any */
698         if (unlikely(__kfifo_len(conn->mgmtqueue))) {
699                 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
700                                    sizeof(void*))) {
701                         spin_lock_bh(&conn->session->lock);
702                         list_add_tail(&conn->mtask->running,
703                                       &conn->mgmt_run_list);
704                         spin_unlock_bh(&conn->session->lock);
705                         rc = iscsi_xmit_mtask(conn);
706                         if (rc)
707                                 goto again;
708                 }
709         }
710
711         return -ENODATA;
712
713 again:
714         if (unlikely(conn->suspend_tx))
715                 return -ENODATA;
716
717         return rc;
718 }
719
720 static void iscsi_xmitworker(struct work_struct *work)
721 {
722         struct iscsi_conn *conn =
723                 container_of(work, struct iscsi_conn, xmitwork);
724         int rc;
725         /*
726          * serialize Xmit worker on a per-connection basis.
727          */
728         mutex_lock(&conn->xmitmutex);
729         do {
730                 rc = iscsi_data_xmit(conn);
731         } while (rc >= 0 || rc == -EAGAIN);
732         mutex_unlock(&conn->xmitmutex);
733 }
734
735 enum {
736         FAILURE_BAD_HOST = 1,
737         FAILURE_SESSION_FAILED,
738         FAILURE_SESSION_FREED,
739         FAILURE_WINDOW_CLOSED,
740         FAILURE_OOM,
741         FAILURE_SESSION_TERMINATE,
742         FAILURE_SESSION_IN_RECOVERY,
743         FAILURE_SESSION_RECOVERY_TIMEOUT,
744 };
745
746 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
747 {
748         struct Scsi_Host *host;
749         int reason = 0;
750         struct iscsi_session *session;
751         struct iscsi_conn *conn;
752         struct iscsi_cmd_task *ctask = NULL;
753
754         sc->scsi_done = done;
755         sc->result = 0;
756         sc->SCp.ptr = NULL;
757
758         host = sc->device->host;
759         session = iscsi_hostdata(host->hostdata);
760
761         spin_lock(&session->lock);
762
763         /*
764          * ISCSI_STATE_FAILED is a temp. state. The recovery
765          * code will decide what is best to do with command queued
766          * during this time
767          */
768         if (session->state != ISCSI_STATE_LOGGED_IN &&
769             session->state != ISCSI_STATE_FAILED) {
770                 /*
771                  * to handle the race between when we set the recovery state
772                  * and block the session we requeue here (commands could
773                  * be entering our queuecommand while a block is starting
774                  * up because the block code is not locked)
775                  */
776                 if (session->state == ISCSI_STATE_IN_RECOVERY) {
777                         reason = FAILURE_SESSION_IN_RECOVERY;
778                         goto reject;
779                 }
780
781                 if (session->state == ISCSI_STATE_RECOVERY_FAILED)
782                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
783                 else if (session->state == ISCSI_STATE_TERMINATE)
784                         reason = FAILURE_SESSION_TERMINATE;
785                 else
786                         reason = FAILURE_SESSION_FREED;
787                 goto fault;
788         }
789
790         /*
791          * Check for iSCSI window and take care of CmdSN wrap-around
792          */
793         if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
794                 reason = FAILURE_WINDOW_CLOSED;
795                 goto reject;
796         }
797
798         conn = session->leadconn;
799         if (!conn) {
800                 reason = FAILURE_SESSION_FREED;
801                 goto fault;
802         }
803
804         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
805                          sizeof(void*))) {
806                 reason = FAILURE_OOM;
807                 goto reject;
808         }
809         sc->SCp.phase = session->age;
810         sc->SCp.ptr = (char *)ctask;
811
812         atomic_set(&ctask->refcount, 1);
813         ctask->state = ISCSI_TASK_PENDING;
814         ctask->mtask = NULL;
815         ctask->conn = conn;
816         ctask->sc = sc;
817         INIT_LIST_HEAD(&ctask->running);
818         iscsi_prep_scsi_cmd_pdu(ctask);
819
820         session->tt->init_cmd_task(ctask);
821
822         list_add_tail(&ctask->running, &conn->xmitqueue);
823         debug_scsi(
824                "ctask enq [%s cid %d sc %p cdb 0x%x itt 0x%x len %d cmdsn %d "
825                 "win %d]\n",
826                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
827                 conn->id, sc, sc->cmnd[0], ctask->itt, sc->request_bufflen,
828                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
829         spin_unlock(&session->lock);
830
831         scsi_queue_work(host, &conn->xmitwork);
832         return 0;
833
834 reject:
835         spin_unlock(&session->lock);
836         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
837         return SCSI_MLQUEUE_HOST_BUSY;
838
839 fault:
840         spin_unlock(&session->lock);
841         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
842                sc->cmnd[0], reason);
843         sc->result = (DID_NO_CONNECT << 16);
844         sc->resid = sc->request_bufflen;
845         sc->scsi_done(sc);
846         return 0;
847 }
848 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
849
850 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
851 {
852         if (depth > ISCSI_MAX_CMD_PER_LUN)
853                 depth = ISCSI_MAX_CMD_PER_LUN;
854         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
855         return sdev->queue_depth;
856 }
857 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
858
859 static int
860 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
861                         char *data, uint32_t data_size)
862 {
863         struct iscsi_session *session = conn->session;
864         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
865         struct iscsi_mgmt_task *mtask;
866
867         spin_lock_bh(&session->lock);
868         if (session->state == ISCSI_STATE_TERMINATE) {
869                 spin_unlock_bh(&session->lock);
870                 return -EPERM;
871         }
872         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
873             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
874                 /*
875                  * Login and Text are sent serially, in
876                  * request-followed-by-response sequence.
877                  * Same mtask can be used. Same ITT must be used.
878                  * Note that login_mtask is preallocated at conn_create().
879                  */
880                 mtask = conn->login_mtask;
881         else {
882                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
883                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
884
885                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
886                 if (!__kfifo_get(session->mgmtpool.queue,
887                                  (void*)&mtask, sizeof(void*))) {
888                         spin_unlock_bh(&session->lock);
889                         return -ENOSPC;
890                 }
891         }
892
893         /*
894          * pre-format CmdSN for outgoing PDU.
895          */
896         if (hdr->itt != RESERVED_ITT) {
897                 hdr->itt = build_itt(mtask->itt, conn->id, session->age);
898                 nop->cmdsn = cpu_to_be32(session->cmdsn);
899                 if (conn->c_stage == ISCSI_CONN_STARTED &&
900                     !(hdr->opcode & ISCSI_OP_IMMEDIATE))
901                         session->cmdsn++;
902         } else
903                 /* do not advance CmdSN */
904                 nop->cmdsn = cpu_to_be32(session->cmdsn);
905
906         if (data_size) {
907                 memcpy(mtask->data, data, data_size);
908                 mtask->data_count = data_size;
909         } else
910                 mtask->data_count = 0;
911
912         INIT_LIST_HEAD(&mtask->running);
913         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
914         if (session->tt->init_mgmt_task)
915                 session->tt->init_mgmt_task(conn, mtask, data, data_size);
916         spin_unlock_bh(&session->lock);
917
918         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
919                    hdr->opcode, hdr->itt, data_size);
920
921         /*
922          * since send_pdu() could be called at least from two contexts,
923          * we need to serialize __kfifo_put, so we don't have to take
924          * additional lock on fast data-path
925          */
926         if (hdr->opcode & ISCSI_OP_IMMEDIATE)
927                 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
928         else
929                 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
930
931         scsi_queue_work(session->host, &conn->xmitwork);
932         return 0;
933 }
934
935 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
936                         char *data, uint32_t data_size)
937 {
938         struct iscsi_conn *conn = cls_conn->dd_data;
939         int rc;
940
941         mutex_lock(&conn->xmitmutex);
942         rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
943         mutex_unlock(&conn->xmitmutex);
944
945         return rc;
946 }
947 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
948
949 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
950 {
951         struct iscsi_session *session = class_to_transport_session(cls_session);
952         struct iscsi_conn *conn = session->leadconn;
953
954         spin_lock_bh(&session->lock);
955         if (session->state != ISCSI_STATE_LOGGED_IN) {
956                 session->state = ISCSI_STATE_RECOVERY_FAILED;
957                 if (conn)
958                         wake_up(&conn->ehwait);
959         }
960         spin_unlock_bh(&session->lock);
961 }
962 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
963
964 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
965 {
966         struct Scsi_Host *host = sc->device->host;
967         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
968         struct iscsi_conn *conn = session->leadconn;
969         int fail_session = 0;
970
971         spin_lock_bh(&session->lock);
972         if (session->state == ISCSI_STATE_TERMINATE) {
973 failed:
974                 debug_scsi("failing host reset: session terminated "
975                            "[CID %d age %d]\n", conn->id, session->age);
976                 spin_unlock_bh(&session->lock);
977                 return FAILED;
978         }
979
980         if (sc->SCp.phase == session->age) {
981                 debug_scsi("failing connection CID %d due to SCSI host reset\n",
982                            conn->id);
983                 fail_session = 1;
984         }
985         spin_unlock_bh(&session->lock);
986
987         /*
988          * we drop the lock here but the leadconn cannot be destoyed while
989          * we are in the scsi eh
990          */
991         if (fail_session)
992                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
993
994         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
995         wait_event_interruptible(conn->ehwait,
996                                  session->state == ISCSI_STATE_TERMINATE ||
997                                  session->state == ISCSI_STATE_LOGGED_IN ||
998                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
999         if (signal_pending(current))
1000                 flush_signals(current);
1001
1002         spin_lock_bh(&session->lock);
1003         if (session->state == ISCSI_STATE_LOGGED_IN)
1004                 printk(KERN_INFO "iscsi: host reset succeeded\n");
1005         else
1006                 goto failed;
1007         spin_unlock_bh(&session->lock);
1008
1009         return SUCCESS;
1010 }
1011 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1012
1013 static void iscsi_tmabort_timedout(unsigned long data)
1014 {
1015         struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
1016         struct iscsi_conn *conn = ctask->conn;
1017         struct iscsi_session *session = conn->session;
1018
1019         spin_lock(&session->lock);
1020         if (conn->tmabort_state == TMABORT_INITIAL) {
1021                 conn->tmabort_state = TMABORT_TIMEDOUT;
1022                 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
1023                         ctask->sc, ctask->itt);
1024                 /* unblock eh_abort() */
1025                 wake_up(&conn->ehwait);
1026         }
1027         spin_unlock(&session->lock);
1028 }
1029
1030 /* must be called with the mutex lock */
1031 static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
1032                                  struct iscsi_cmd_task *ctask)
1033 {
1034         struct iscsi_conn *conn = ctask->conn;
1035         struct iscsi_session *session = conn->session;
1036         struct iscsi_tm *hdr = &conn->tmhdr;
1037         int rc;
1038
1039         /*
1040          * ctask timed out but session is OK requests must be serialized.
1041          */
1042         memset(hdr, 0, sizeof(struct iscsi_tm));
1043         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1044         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
1045         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1046         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1047         hdr->rtt = ctask->hdr->itt;
1048         hdr->refcmdsn = ctask->hdr->cmdsn;
1049
1050         rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
1051                                      NULL, 0);
1052         if (rc) {
1053                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1054                 debug_scsi("abort sent failure [itt 0x%x] %d\n", ctask->itt,
1055                            rc);
1056                 return rc;
1057         }
1058
1059         debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
1060
1061         spin_lock_bh(&session->lock);
1062         ctask->mtask = (struct iscsi_mgmt_task *)
1063                         session->mgmt_cmds[get_itt(hdr->itt) -
1064                                         ISCSI_MGMT_ITT_OFFSET];
1065
1066         if (conn->tmabort_state == TMABORT_INITIAL) {
1067                 conn->tmfcmd_pdus_cnt++;
1068                 conn->tmabort_timer.expires = 10*HZ + jiffies;
1069                 conn->tmabort_timer.function = iscsi_tmabort_timedout;
1070                 conn->tmabort_timer.data = (unsigned long)ctask;
1071                 add_timer(&conn->tmabort_timer);
1072                 debug_scsi("abort set timeout [itt 0x%x]\n", ctask->itt);
1073         }
1074         spin_unlock_bh(&session->lock);
1075         mutex_unlock(&conn->xmitmutex);
1076
1077         /*
1078          * block eh thread until:
1079          *
1080          * 1) abort response
1081          * 2) abort timeout
1082          * 3) session is terminated or restarted or userspace has
1083          * given up on recovery
1084          */
1085         wait_event_interruptible(conn->ehwait,
1086                                  sc->SCp.phase != session->age ||
1087                                  session->state != ISCSI_STATE_LOGGED_IN ||
1088                                  conn->tmabort_state != TMABORT_INITIAL);
1089         if (signal_pending(current))
1090                 flush_signals(current);
1091         del_timer_sync(&conn->tmabort_timer);
1092
1093         mutex_lock(&conn->xmitmutex);
1094         return 0;
1095 }
1096
1097 /*
1098  * xmit mutex and session lock must be held
1099  */
1100 static struct iscsi_mgmt_task *
1101 iscsi_remove_mgmt_task(struct kfifo *fifo, uint32_t itt)
1102 {
1103         int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*);
1104         struct iscsi_mgmt_task *task;
1105
1106         debug_scsi("searching %d tasks\n", nr_tasks);
1107
1108         for (i = 0; i < nr_tasks; i++) {
1109                 __kfifo_get(fifo, (void*)&task, sizeof(void*));
1110                 debug_scsi("check task %u\n", task->itt);
1111
1112                 if (task->itt == itt) {
1113                         debug_scsi("matched task\n");
1114                         return task;
1115                 }
1116
1117                 __kfifo_put(fifo, (void*)&task, sizeof(void*));
1118         }
1119         return NULL;
1120 }
1121
1122 static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
1123 {
1124         struct iscsi_conn *conn = ctask->conn;
1125         struct iscsi_session *session = conn->session;
1126
1127         if (!ctask->mtask)
1128                 return -EINVAL;
1129
1130         if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
1131                 list_del(&ctask->mtask->running);
1132         __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
1133                     sizeof(void*));
1134         ctask->mtask = NULL;
1135         return 0;
1136 }
1137
1138 /*
1139  * session lock and xmitmutex must be held
1140  */
1141 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1142                          int err)
1143 {
1144         struct scsi_cmnd *sc;
1145
1146         sc = ctask->sc;
1147         if (!sc)
1148                 return;
1149
1150         conn->session->tt->cleanup_cmd_task(conn, ctask);
1151         iscsi_ctask_mtask_cleanup(ctask);
1152
1153         sc->result = err;
1154         sc->resid = sc->request_bufflen;
1155         /* release ref from queuecommand */
1156         __iscsi_put_ctask(ctask);
1157 }
1158
1159 int iscsi_eh_abort(struct scsi_cmnd *sc)
1160 {
1161         struct iscsi_cmd_task *ctask;
1162         struct iscsi_conn *conn;
1163         struct iscsi_session *session;
1164         int rc;
1165
1166         /*
1167          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1168          * got the command.
1169          */
1170         if (!sc->SCp.ptr) {
1171                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1172                 return SUCCESS;
1173         }
1174
1175         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1176         conn = ctask->conn;
1177         session = conn->session;
1178
1179         conn->eh_abort_cnt++;
1180         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1181
1182         mutex_lock(&conn->xmitmutex);
1183         spin_lock_bh(&session->lock);
1184
1185         /*
1186          * If we are not logged in or we have started a new session
1187          * then let the host reset code handle this
1188          */
1189         if (session->state != ISCSI_STATE_LOGGED_IN ||
1190             sc->SCp.phase != session->age)
1191                 goto failed;
1192
1193         /* ctask completed before time out */
1194         if (!ctask->sc) {
1195                 spin_unlock_bh(&session->lock);
1196                 debug_scsi("sc completed while abort in progress\n");
1197                 goto success_rel_mutex;
1198         }
1199
1200         /* what should we do here ? */
1201         if (conn->ctask == ctask) {
1202                 printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
1203                        "Failing abort\n", sc, ctask->itt);
1204                 goto failed;
1205         }
1206
1207         if (ctask->state == ISCSI_TASK_PENDING)
1208                 goto success_cleanup;
1209
1210         conn->tmabort_state = TMABORT_INITIAL;
1211
1212         spin_unlock_bh(&session->lock);
1213         rc = iscsi_exec_abort_task(sc, ctask);
1214         spin_lock_bh(&session->lock);
1215
1216         if (rc || sc->SCp.phase != session->age ||
1217             session->state != ISCSI_STATE_LOGGED_IN)
1218                 goto failed;
1219         iscsi_ctask_mtask_cleanup(ctask);
1220
1221         switch (conn->tmabort_state) {
1222         case TMABORT_SUCCESS:
1223                 goto success_cleanup;
1224         case TMABORT_NOT_FOUND:
1225                 if (!ctask->sc) {
1226                         /* ctask completed before tmf abort response */
1227                         spin_unlock_bh(&session->lock);
1228                         debug_scsi("sc completed while abort in progress\n");
1229                         goto success_rel_mutex;
1230                 }
1231                 /* fall through */
1232         default:
1233                 /* timedout or failed */
1234                 spin_unlock_bh(&session->lock);
1235                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1236                 spin_lock_bh(&session->lock);
1237                 goto failed;
1238         }
1239
1240 success_cleanup:
1241         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1242         spin_unlock_bh(&session->lock);
1243
1244         /*
1245          * clean up task if aborted. we have the xmitmutex so grab
1246          * the recv lock as a writer
1247          */
1248         write_lock_bh(conn->recv_lock);
1249         spin_lock(&session->lock);
1250         fail_command(conn, ctask, DID_ABORT << 16);
1251         spin_unlock(&session->lock);
1252         write_unlock_bh(conn->recv_lock);
1253
1254 success_rel_mutex:
1255         mutex_unlock(&conn->xmitmutex);
1256         return SUCCESS;
1257
1258 failed:
1259         spin_unlock_bh(&session->lock);
1260         mutex_unlock(&conn->xmitmutex);
1261
1262         debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1263         return FAILED;
1264 }
1265 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1266
1267 int
1268 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1269 {
1270         int i;
1271
1272         *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1273         if (*items == NULL)
1274                 return -ENOMEM;
1275
1276         q->max = max;
1277         q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1278         if (q->pool == NULL) {
1279                 kfree(*items);
1280                 return -ENOMEM;
1281         }
1282
1283         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1284                               GFP_KERNEL, NULL);
1285         if (q->queue == ERR_PTR(-ENOMEM)) {
1286                 kfree(q->pool);
1287                 kfree(*items);
1288                 return -ENOMEM;
1289         }
1290
1291         for (i = 0; i < max; i++) {
1292                 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1293                 if (q->pool[i] == NULL) {
1294                         int j;
1295
1296                         for (j = 0; j < i; j++)
1297                                 kfree(q->pool[j]);
1298
1299                         kfifo_free(q->queue);
1300                         kfree(q->pool);
1301                         kfree(*items);
1302                         return -ENOMEM;
1303                 }
1304                 memset(q->pool[i], 0, item_size);
1305                 (*items)[i] = q->pool[i];
1306                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1307         }
1308         return 0;
1309 }
1310 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1311
1312 void iscsi_pool_free(struct iscsi_queue *q, void **items)
1313 {
1314         int i;
1315
1316         for (i = 0; i < q->max; i++)
1317                 kfree(items[i]);
1318         kfree(q->pool);
1319         kfree(items);
1320 }
1321 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1322
1323 /*
1324  * iSCSI Session's hostdata organization:
1325  *
1326  *    *------------------* <== hostdata_session(host->hostdata)
1327  *    | ptr to class sess|
1328  *    |------------------| <== iscsi_hostdata(host->hostdata)
1329  *    | iscsi_session    |
1330  *    *------------------*
1331  */
1332
1333 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1334                                  _sz % sizeof(unsigned long))
1335
1336 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1337
1338 /**
1339  * iscsi_session_setup - create iscsi cls session and host and session
1340  * @scsit: scsi transport template
1341  * @iscsit: iscsi transport template
1342  * @initial_cmdsn: initial CmdSN
1343  * @hostno: host no allocated
1344  *
1345  * This can be used by software iscsi_transports that allocate
1346  * a session per scsi host.
1347  **/
1348 struct iscsi_cls_session *
1349 iscsi_session_setup(struct iscsi_transport *iscsit,
1350                     struct scsi_transport_template *scsit,
1351                     int cmd_task_size, int mgmt_task_size,
1352                     uint32_t initial_cmdsn, uint32_t *hostno)
1353 {
1354         struct Scsi_Host *shost;
1355         struct iscsi_session *session;
1356         struct iscsi_cls_session *cls_session;
1357         int cmd_i;
1358
1359         shost = scsi_host_alloc(iscsit->host_template,
1360                                 hostdata_privsize(sizeof(*session)));
1361         if (!shost)
1362                 return NULL;
1363
1364         shost->max_id = 1;
1365         shost->max_channel = 0;
1366         shost->max_lun = iscsit->max_lun;
1367         shost->max_cmd_len = iscsit->max_cmd_len;
1368         shost->transportt = scsit;
1369         shost->transportt->create_work_queue = 1;
1370         *hostno = shost->host_no;
1371
1372         session = iscsi_hostdata(shost->hostdata);
1373         memset(session, 0, sizeof(struct iscsi_session));
1374         session->host = shost;
1375         session->state = ISCSI_STATE_FREE;
1376         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1377         session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1378         session->cmdsn = initial_cmdsn;
1379         session->exp_cmdsn = initial_cmdsn + 1;
1380         session->max_cmdsn = initial_cmdsn + 1;
1381         session->max_r2t = 1;
1382         session->tt = iscsit;
1383
1384         /* initialize SCSI PDU commands pool */
1385         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1386                             (void***)&session->cmds,
1387                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1388                 goto cmdpool_alloc_fail;
1389
1390         /* pre-format cmds pool with ITT */
1391         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1392                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1393
1394                 if (cmd_task_size)
1395                         ctask->dd_data = &ctask[1];
1396                 ctask->itt = cmd_i;
1397                 INIT_LIST_HEAD(&ctask->running);
1398         }
1399
1400         spin_lock_init(&session->lock);
1401
1402         /* initialize immediate command pool */
1403         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1404                            (void***)&session->mgmt_cmds,
1405                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1406                 goto mgmtpool_alloc_fail;
1407
1408
1409         /* pre-format immediate cmds pool with ITT */
1410         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1411                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1412
1413                 if (mgmt_task_size)
1414                         mtask->dd_data = &mtask[1];
1415                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1416                 INIT_LIST_HEAD(&mtask->running);
1417         }
1418
1419         if (scsi_add_host(shost, NULL))
1420                 goto add_host_fail;
1421
1422         if (!try_module_get(iscsit->owner))
1423                 goto cls_session_fail;
1424
1425         cls_session = iscsi_create_session(shost, iscsit, 0);
1426         if (!cls_session)
1427                 goto module_put;
1428         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1429
1430         return cls_session;
1431
1432 module_put:
1433         module_put(iscsit->owner);
1434 cls_session_fail:
1435         scsi_remove_host(shost);
1436 add_host_fail:
1437         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1438 mgmtpool_alloc_fail:
1439         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1440 cmdpool_alloc_fail:
1441         scsi_host_put(shost);
1442         return NULL;
1443 }
1444 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1445
1446 /**
1447  * iscsi_session_teardown - destroy session, host, and cls_session
1448  * shost: scsi host
1449  *
1450  * This can be used by software iscsi_transports that allocate
1451  * a session per scsi host.
1452  **/
1453 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1454 {
1455         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1456         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1457         struct module *owner = cls_session->transport->owner;
1458
1459         scsi_remove_host(shost);
1460
1461         iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1462         iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1463
1464         kfree(session->targetname);
1465         kfree(session->hwaddress);
1466         kfree(session->initiatorname);
1467
1468         iscsi_destroy_session(cls_session);
1469         scsi_host_put(shost);
1470         module_put(owner);
1471 }
1472 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1473
1474 /**
1475  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1476  * @cls_session: iscsi_cls_session
1477  * @conn_idx: cid
1478  **/
1479 struct iscsi_cls_conn *
1480 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1481 {
1482         struct iscsi_session *session = class_to_transport_session(cls_session);
1483         struct iscsi_conn *conn;
1484         struct iscsi_cls_conn *cls_conn;
1485         char *data;
1486
1487         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1488         if (!cls_conn)
1489                 return NULL;
1490         conn = cls_conn->dd_data;
1491         memset(conn, 0, sizeof(*conn));
1492
1493         conn->session = session;
1494         conn->cls_conn = cls_conn;
1495         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1496         conn->id = conn_idx;
1497         conn->exp_statsn = 0;
1498         conn->tmabort_state = TMABORT_INITIAL;
1499         INIT_LIST_HEAD(&conn->run_list);
1500         INIT_LIST_HEAD(&conn->mgmt_run_list);
1501         INIT_LIST_HEAD(&conn->xmitqueue);
1502
1503         /* initialize general immediate & non-immediate PDU commands queue */
1504         conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1505                                         GFP_KERNEL, NULL);
1506         if (conn->immqueue == ERR_PTR(-ENOMEM))
1507                 goto immqueue_alloc_fail;
1508
1509         conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1510                                         GFP_KERNEL, NULL);
1511         if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1512                 goto mgmtqueue_alloc_fail;
1513
1514         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1515
1516         /* allocate login_mtask used for the login/text sequences */
1517         spin_lock_bh(&session->lock);
1518         if (!__kfifo_get(session->mgmtpool.queue,
1519                          (void*)&conn->login_mtask,
1520                          sizeof(void*))) {
1521                 spin_unlock_bh(&session->lock);
1522                 goto login_mtask_alloc_fail;
1523         }
1524         spin_unlock_bh(&session->lock);
1525
1526         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1527         if (!data)
1528                 goto login_mtask_data_alloc_fail;
1529         conn->login_mtask->data = conn->data = data;
1530
1531         init_timer(&conn->tmabort_timer);
1532         mutex_init(&conn->xmitmutex);
1533         init_waitqueue_head(&conn->ehwait);
1534
1535         return cls_conn;
1536
1537 login_mtask_data_alloc_fail:
1538         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1539                     sizeof(void*));
1540 login_mtask_alloc_fail:
1541         kfifo_free(conn->mgmtqueue);
1542 mgmtqueue_alloc_fail:
1543         kfifo_free(conn->immqueue);
1544 immqueue_alloc_fail:
1545         iscsi_destroy_conn(cls_conn);
1546         return NULL;
1547 }
1548 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1549
1550 /**
1551  * iscsi_conn_teardown - teardown iscsi connection
1552  * cls_conn: iscsi class connection
1553  *
1554  * TODO: we may need to make this into a two step process
1555  * like scsi-mls remove + put host
1556  */
1557 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1558 {
1559         struct iscsi_conn *conn = cls_conn->dd_data;
1560         struct iscsi_session *session = conn->session;
1561         unsigned long flags;
1562
1563         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1564         mutex_lock(&conn->xmitmutex);
1565
1566         spin_lock_bh(&session->lock);
1567         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1568         if (session->leadconn == conn) {
1569                 /*
1570                  * leading connection? then give up on recovery.
1571                  */
1572                 session->state = ISCSI_STATE_TERMINATE;
1573                 wake_up(&conn->ehwait);
1574         }
1575         spin_unlock_bh(&session->lock);
1576
1577         mutex_unlock(&conn->xmitmutex);
1578
1579         /*
1580          * Block until all in-progress commands for this connection
1581          * time out or fail.
1582          */
1583         for (;;) {
1584                 spin_lock_irqsave(session->host->host_lock, flags);
1585                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1586                         spin_unlock_irqrestore(session->host->host_lock, flags);
1587                         break;
1588                 }
1589                 spin_unlock_irqrestore(session->host->host_lock, flags);
1590                 msleep_interruptible(500);
1591                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1592                        "host_failed %d\n", session->host->host_busy,
1593                        session->host->host_failed);
1594                 /*
1595                  * force eh_abort() to unblock
1596                  */
1597                 wake_up(&conn->ehwait);
1598         }
1599
1600         /* flush queued up work because we free the connection below */
1601         scsi_flush_work(session->host);
1602
1603         spin_lock_bh(&session->lock);
1604         kfree(conn->data);
1605         kfree(conn->persistent_address);
1606         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1607                     sizeof(void*));
1608         if (session->leadconn == conn) {
1609                 session->leadconn = NULL;
1610                 /* no connections exits.. reset sequencing */
1611                 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1612         }
1613         spin_unlock_bh(&session->lock);
1614
1615         kfifo_free(conn->immqueue);
1616         kfifo_free(conn->mgmtqueue);
1617
1618         iscsi_destroy_conn(cls_conn);
1619 }
1620 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1621
1622 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1623 {
1624         struct iscsi_conn *conn = cls_conn->dd_data;
1625         struct iscsi_session *session = conn->session;
1626
1627         if (!session) {
1628                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1629                 return -EPERM;
1630         }
1631
1632         if ((session->imm_data_en || !session->initial_r2t_en) &&
1633              session->first_burst > session->max_burst) {
1634                 printk("iscsi: invalid burst lengths: "
1635                        "first_burst %d max_burst %d\n",
1636                        session->first_burst, session->max_burst);
1637                 return -EINVAL;
1638         }
1639
1640         spin_lock_bh(&session->lock);
1641         conn->c_stage = ISCSI_CONN_STARTED;
1642         session->state = ISCSI_STATE_LOGGED_IN;
1643
1644         switch(conn->stop_stage) {
1645         case STOP_CONN_RECOVER:
1646                 /*
1647                  * unblock eh_abort() if it is blocked. re-try all
1648                  * commands after successful recovery
1649                  */
1650                 conn->stop_stage = 0;
1651                 conn->tmabort_state = TMABORT_INITIAL;
1652                 session->age++;
1653                 spin_unlock_bh(&session->lock);
1654
1655                 iscsi_unblock_session(session_to_cls(session));
1656                 wake_up(&conn->ehwait);
1657                 return 0;
1658         case STOP_CONN_TERM:
1659                 conn->stop_stage = 0;
1660                 break;
1661         default:
1662                 break;
1663         }
1664         spin_unlock_bh(&session->lock);
1665
1666         return 0;
1667 }
1668 EXPORT_SYMBOL_GPL(iscsi_conn_start);
1669
1670 static void
1671 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1672 {
1673         struct iscsi_mgmt_task *mtask, *tmp;
1674
1675         /* handle pending */
1676         while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1677                __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1678                 if (mtask == conn->login_mtask)
1679                         continue;
1680                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1681                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1682                             sizeof(void*));
1683         }
1684
1685         /* handle running */
1686         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1687                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1688                 list_del(&mtask->running);
1689
1690                 if (mtask == conn->login_mtask)
1691                         continue;
1692                 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1693                            sizeof(void*));
1694         }
1695
1696         conn->mtask = NULL;
1697 }
1698
1699 /* Fail commands. Mutex and session lock held and recv side suspended */
1700 static void fail_all_commands(struct iscsi_conn *conn)
1701 {
1702         struct iscsi_cmd_task *ctask, *tmp;
1703
1704         /* flush pending */
1705         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1706                 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1707                            ctask->itt);
1708                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1709         }
1710
1711         /* fail all other running */
1712         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1713                 debug_scsi("failing in progress sc %p itt 0x%x\n",
1714                            ctask->sc, ctask->itt);
1715                 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1716         }
1717
1718         conn->ctask = NULL;
1719 }
1720
1721 static void iscsi_start_session_recovery(struct iscsi_session *session,
1722                                          struct iscsi_conn *conn, int flag)
1723 {
1724         int old_stop_stage;
1725
1726         spin_lock_bh(&session->lock);
1727         if (conn->stop_stage == STOP_CONN_TERM) {
1728                 spin_unlock_bh(&session->lock);
1729                 return;
1730         }
1731
1732         /*
1733          * When this is called for the in_login state, we only want to clean
1734          * up the login task and connection. We do not need to block and set
1735          * the recovery state again
1736          */
1737         if (flag == STOP_CONN_TERM)
1738                 session->state = ISCSI_STATE_TERMINATE;
1739         else if (conn->stop_stage != STOP_CONN_RECOVER)
1740                 session->state = ISCSI_STATE_IN_RECOVERY;
1741
1742         old_stop_stage = conn->stop_stage;
1743         conn->stop_stage = flag;
1744         conn->c_stage = ISCSI_CONN_STOPPED;
1745         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1746         spin_unlock_bh(&session->lock);
1747
1748         write_lock_bh(conn->recv_lock);
1749         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1750         write_unlock_bh(conn->recv_lock);
1751
1752         mutex_lock(&conn->xmitmutex);
1753         /*
1754          * for connection level recovery we should not calculate
1755          * header digest. conn->hdr_size used for optimization
1756          * in hdr_extract() and will be re-negotiated at
1757          * set_param() time.
1758          */
1759         if (flag == STOP_CONN_RECOVER) {
1760                 conn->hdrdgst_en = 0;
1761                 conn->datadgst_en = 0;
1762                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
1763                     old_stop_stage != STOP_CONN_RECOVER) {
1764                         debug_scsi("blocking session\n");
1765                         iscsi_block_session(session_to_cls(session));
1766                 }
1767         }
1768
1769         /*
1770          * flush queues.
1771          */
1772         spin_lock_bh(&session->lock);
1773         fail_all_commands(conn);
1774         flush_control_queues(session, conn);
1775         spin_unlock_bh(&session->lock);
1776
1777         mutex_unlock(&conn->xmitmutex);
1778 }
1779
1780 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1781 {
1782         struct iscsi_conn *conn = cls_conn->dd_data;
1783         struct iscsi_session *session = conn->session;
1784
1785         switch (flag) {
1786         case STOP_CONN_RECOVER:
1787         case STOP_CONN_TERM:
1788                 iscsi_start_session_recovery(session, conn, flag);
1789                 break;
1790         default:
1791                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
1792         }
1793 }
1794 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1795
1796 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1797                     struct iscsi_cls_conn *cls_conn, int is_leading)
1798 {
1799         struct iscsi_session *session = class_to_transport_session(cls_session);
1800         struct iscsi_conn *conn = cls_conn->dd_data;
1801
1802         spin_lock_bh(&session->lock);
1803         if (is_leading)
1804                 session->leadconn = conn;
1805         spin_unlock_bh(&session->lock);
1806
1807         /*
1808          * Unblock xmitworker(), Login Phase will pass through.
1809          */
1810         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1811         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1812         return 0;
1813 }
1814 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1815
1816
1817 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
1818                     enum iscsi_param param, char *buf, int buflen)
1819 {
1820         struct iscsi_conn *conn = cls_conn->dd_data;
1821         struct iscsi_session *session = conn->session;
1822         uint32_t value;
1823
1824         switch(param) {
1825         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1826                 sscanf(buf, "%d", &conn->max_recv_dlength);
1827                 break;
1828         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1829                 sscanf(buf, "%d", &conn->max_xmit_dlength);
1830                 break;
1831         case ISCSI_PARAM_HDRDGST_EN:
1832                 sscanf(buf, "%d", &conn->hdrdgst_en);
1833                 break;
1834         case ISCSI_PARAM_DATADGST_EN:
1835                 sscanf(buf, "%d", &conn->datadgst_en);
1836                 break;
1837         case ISCSI_PARAM_INITIAL_R2T_EN:
1838                 sscanf(buf, "%d", &session->initial_r2t_en);
1839                 break;
1840         case ISCSI_PARAM_MAX_R2T:
1841                 sscanf(buf, "%d", &session->max_r2t);
1842                 break;
1843         case ISCSI_PARAM_IMM_DATA_EN:
1844                 sscanf(buf, "%d", &session->imm_data_en);
1845                 break;
1846         case ISCSI_PARAM_FIRST_BURST:
1847                 sscanf(buf, "%d", &session->first_burst);
1848                 break;
1849         case ISCSI_PARAM_MAX_BURST:
1850                 sscanf(buf, "%d", &session->max_burst);
1851                 break;
1852         case ISCSI_PARAM_PDU_INORDER_EN:
1853                 sscanf(buf, "%d", &session->pdu_inorder_en);
1854                 break;
1855         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1856                 sscanf(buf, "%d", &session->dataseq_inorder_en);
1857                 break;
1858         case ISCSI_PARAM_ERL:
1859                 sscanf(buf, "%d", &session->erl);
1860                 break;
1861         case ISCSI_PARAM_IFMARKER_EN:
1862                 sscanf(buf, "%d", &value);
1863                 BUG_ON(value);
1864                 break;
1865         case ISCSI_PARAM_OFMARKER_EN:
1866                 sscanf(buf, "%d", &value);
1867                 BUG_ON(value);
1868                 break;
1869         case ISCSI_PARAM_EXP_STATSN:
1870                 sscanf(buf, "%u", &conn->exp_statsn);
1871                 break;
1872         case ISCSI_PARAM_TARGET_NAME:
1873                 /* this should not change between logins */
1874                 if (session->targetname)
1875                         break;
1876
1877                 session->targetname = kstrdup(buf, GFP_KERNEL);
1878                 if (!session->targetname)
1879                         return -ENOMEM;
1880                 break;
1881         case ISCSI_PARAM_TPGT:
1882                 sscanf(buf, "%d", &session->tpgt);
1883                 break;
1884         case ISCSI_PARAM_PERSISTENT_PORT:
1885                 sscanf(buf, "%d", &conn->persistent_port);
1886                 break;
1887         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1888                 /*
1889                  * this is the address returned in discovery so it should
1890                  * not change between logins.
1891                  */
1892                 if (conn->persistent_address)
1893                         break;
1894
1895                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
1896                 if (!conn->persistent_address)
1897                         return -ENOMEM;
1898                 break;
1899         default:
1900                 return -ENOSYS;
1901         }
1902
1903         return 0;
1904 }
1905 EXPORT_SYMBOL_GPL(iscsi_set_param);
1906
1907 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
1908                             enum iscsi_param param, char *buf)
1909 {
1910         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1911         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1912         int len;
1913
1914         switch(param) {
1915         case ISCSI_PARAM_INITIAL_R2T_EN:
1916                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
1917                 break;
1918         case ISCSI_PARAM_MAX_R2T:
1919                 len = sprintf(buf, "%hu\n", session->max_r2t);
1920                 break;
1921         case ISCSI_PARAM_IMM_DATA_EN:
1922                 len = sprintf(buf, "%d\n", session->imm_data_en);
1923                 break;
1924         case ISCSI_PARAM_FIRST_BURST:
1925                 len = sprintf(buf, "%u\n", session->first_burst);
1926                 break;
1927         case ISCSI_PARAM_MAX_BURST:
1928                 len = sprintf(buf, "%u\n", session->max_burst);
1929                 break;
1930         case ISCSI_PARAM_PDU_INORDER_EN:
1931                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
1932                 break;
1933         case ISCSI_PARAM_DATASEQ_INORDER_EN:
1934                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
1935                 break;
1936         case ISCSI_PARAM_ERL:
1937                 len = sprintf(buf, "%d\n", session->erl);
1938                 break;
1939         case ISCSI_PARAM_TARGET_NAME:
1940                 len = sprintf(buf, "%s\n", session->targetname);
1941                 break;
1942         case ISCSI_PARAM_TPGT:
1943                 len = sprintf(buf, "%d\n", session->tpgt);
1944                 break;
1945         default:
1946                 return -ENOSYS;
1947         }
1948
1949         return len;
1950 }
1951 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
1952
1953 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
1954                          enum iscsi_param param, char *buf)
1955 {
1956         struct iscsi_conn *conn = cls_conn->dd_data;
1957         int len;
1958
1959         switch(param) {
1960         case ISCSI_PARAM_MAX_RECV_DLENGTH:
1961                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
1962                 break;
1963         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
1964                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
1965                 break;
1966         case ISCSI_PARAM_HDRDGST_EN:
1967                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
1968                 break;
1969         case ISCSI_PARAM_DATADGST_EN:
1970                 len = sprintf(buf, "%d\n", conn->datadgst_en);
1971                 break;
1972         case ISCSI_PARAM_IFMARKER_EN:
1973                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
1974                 break;
1975         case ISCSI_PARAM_OFMARKER_EN:
1976                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
1977                 break;
1978         case ISCSI_PARAM_EXP_STATSN:
1979                 len = sprintf(buf, "%u\n", conn->exp_statsn);
1980                 break;
1981         case ISCSI_PARAM_PERSISTENT_PORT:
1982                 len = sprintf(buf, "%d\n", conn->persistent_port);
1983                 break;
1984         case ISCSI_PARAM_PERSISTENT_ADDRESS:
1985                 len = sprintf(buf, "%s\n", conn->persistent_address);
1986                 break;
1987         default:
1988                 return -ENOSYS;
1989         }
1990
1991         return len;
1992 }
1993 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
1994
1995 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
1996                          char *buf)
1997 {
1998         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1999         int len;
2000
2001         switch (param) {
2002         case ISCSI_HOST_PARAM_HWADDRESS:
2003                 if (!session->hwaddress)
2004                         len = sprintf(buf, "%s\n", "default");
2005                 else
2006                         len = sprintf(buf, "%s\n", session->hwaddress);
2007                 break;
2008         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2009                 if (!session->initiatorname)
2010                         len = sprintf(buf, "%s\n", "unknown");
2011                 else
2012                         len = sprintf(buf, "%s\n", session->initiatorname);
2013                 break;
2014
2015         default:
2016                 return -ENOSYS;
2017         }
2018
2019         return len;
2020 }
2021 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2022
2023 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2024                          char *buf, int buflen)
2025 {
2026         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2027
2028         switch (param) {
2029         case ISCSI_HOST_PARAM_HWADDRESS:
2030                 if (!session->hwaddress)
2031                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2032                 break;
2033         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2034                 if (!session->initiatorname)
2035                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2036                 break;
2037         default:
2038                 return -ENOSYS;
2039         }
2040
2041         return 0;
2042 }
2043 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2044
2045 MODULE_AUTHOR("Mike Christie");
2046 MODULE_DESCRIPTION("iSCSI library functions");
2047 MODULE_LICENSE("GPL");