Merge branch 'x86/setup' into x86/devel
[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/kfifo.h>
26 #include <linux/delay.h>
27 #include <linux/log2.h>
28 #include <asm/unaligned.h>
29 #include <net/tcp.h>
30 #include <scsi/scsi_cmnd.h>
31 #include <scsi/scsi_device.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_tcq.h>
34 #include <scsi/scsi_host.h>
35 #include <scsi/scsi.h>
36 #include <scsi/iscsi_proto.h>
37 #include <scsi/scsi_transport.h>
38 #include <scsi/scsi_transport_iscsi.h>
39 #include <scsi/libiscsi.h>
40
41 struct iscsi_session *
42 class_to_transport_session(struct iscsi_cls_session *cls_session)
43 {
44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
45         return iscsi_hostdata(shost->hostdata);
46 }
47 EXPORT_SYMBOL_GPL(class_to_transport_session);
48
49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
50 #define SNA32_CHECK 2147483648UL
51
52 static int iscsi_sna_lt(u32 n1, u32 n2)
53 {
54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
56 }
57
58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
59 static int iscsi_sna_lte(u32 n1, u32 n2)
60 {
61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
63 }
64
65 void
66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
67 {
68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
70
71         /*
72          * standard specifies this check for when to update expected and
73          * max sequence numbers
74          */
75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
76                 return;
77
78         if (exp_cmdsn != session->exp_cmdsn &&
79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
80                 session->exp_cmdsn = exp_cmdsn;
81
82         if (max_cmdsn != session->max_cmdsn &&
83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
84                 session->max_cmdsn = max_cmdsn;
85                 /*
86                  * if the window closed with IO queued, then kick the
87                  * xmit thread
88                  */
89                 if (!list_empty(&session->leadconn->xmitqueue) ||
90                     !list_empty(&session->leadconn->mgmtqueue))
91                         scsi_queue_work(session->host,
92                                         &session->leadconn->xmitwork);
93         }
94 }
95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
96
97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
98                                    struct iscsi_data *hdr)
99 {
100         struct iscsi_conn *conn = ctask->conn;
101
102         memset(hdr, 0, sizeof(struct iscsi_data));
103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
105         ctask->unsol_datasn++;
106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
108
109         hdr->itt = ctask->hdr->itt;
110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
112
113         if (ctask->unsol_count > conn->max_xmit_dlength) {
114                 hton24(hdr->dlength, conn->max_xmit_dlength);
115                 ctask->data_count = conn->max_xmit_dlength;
116                 ctask->unsol_offset += ctask->data_count;
117                 hdr->flags = 0;
118         } else {
119                 hton24(hdr->dlength, ctask->unsol_count);
120                 ctask->data_count = ctask->unsol_count;
121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
122         }
123 }
124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
125
126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
127 {
128         unsigned exp_len = ctask->hdr_len + len;
129
130         if (exp_len > ctask->hdr_max) {
131                 WARN_ON(1);
132                 return -EINVAL;
133         }
134
135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
136         ctask->hdr_len = exp_len;
137         return 0;
138 }
139
140 /*
141  * make an extended cdb AHS
142  */
143 static int iscsi_prep_ecdb_ahs(struct iscsi_cmd_task *ctask)
144 {
145         struct scsi_cmnd *cmd = ctask->sc;
146         unsigned rlen, pad_len;
147         unsigned short ahslength;
148         struct iscsi_ecdb_ahdr *ecdb_ahdr;
149         int rc;
150
151         ecdb_ahdr = iscsi_next_hdr(ctask);
152         rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
153
154         BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
155         ahslength = rlen + sizeof(ecdb_ahdr->reserved);
156
157         pad_len = iscsi_padding(rlen);
158
159         rc = iscsi_add_hdr(ctask, sizeof(ecdb_ahdr->ahslength) +
160                            sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
161         if (rc)
162                 return rc;
163
164         if (pad_len)
165                 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
166
167         ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
168         ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
169         ecdb_ahdr->reserved = 0;
170         memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
171
172         debug_scsi("iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
173                    "rlen %d pad_len %d ahs_length %d iscsi_headers_size %u\n",
174                    cmd->cmd_len, rlen, pad_len, ahslength, ctask->hdr_len);
175
176         return 0;
177 }
178
179 static int iscsi_prep_bidi_ahs(struct iscsi_cmd_task *ctask)
180 {
181         struct scsi_cmnd *sc = ctask->sc;
182         struct iscsi_rlength_ahdr *rlen_ahdr;
183         int rc;
184
185         rlen_ahdr = iscsi_next_hdr(ctask);
186         rc = iscsi_add_hdr(ctask, sizeof(*rlen_ahdr));
187         if (rc)
188                 return rc;
189
190         rlen_ahdr->ahslength =
191                 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
192                                                   sizeof(rlen_ahdr->reserved));
193         rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
194         rlen_ahdr->reserved = 0;
195         rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
196
197         debug_scsi("bidi-in rlen_ahdr->read_length(%d) "
198                    "rlen_ahdr->ahslength(%d)\n",
199                    be32_to_cpu(rlen_ahdr->read_length),
200                    be16_to_cpu(rlen_ahdr->ahslength));
201         return 0;
202 }
203
204 /**
205  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
206  * @ctask: iscsi cmd task
207  *
208  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
209  * fields like dlength or final based on how much data it sends
210  */
211 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
212 {
213         struct iscsi_conn *conn = ctask->conn;
214         struct iscsi_session *session = conn->session;
215         struct iscsi_cmd *hdr = ctask->hdr;
216         struct scsi_cmnd *sc = ctask->sc;
217         unsigned hdrlength, cmd_len;
218         int rc;
219
220         ctask->hdr_len = 0;
221         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
222         if (rc)
223                 return rc;
224         hdr->opcode = ISCSI_OP_SCSI_CMD;
225         hdr->flags = ISCSI_ATTR_SIMPLE;
226         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
227         hdr->itt = build_itt(ctask->itt, session->age);
228         hdr->cmdsn = cpu_to_be32(session->cmdsn);
229         session->cmdsn++;
230         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
231         cmd_len = sc->cmd_len;
232         if (cmd_len < ISCSI_CDB_SIZE)
233                 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
234         else if (cmd_len > ISCSI_CDB_SIZE) {
235                 rc = iscsi_prep_ecdb_ahs(ctask);
236                 if (rc)
237                         return rc;
238                 cmd_len = ISCSI_CDB_SIZE;
239         }
240         memcpy(hdr->cdb, sc->cmnd, cmd_len);
241
242         ctask->imm_count = 0;
243         if (scsi_bidi_cmnd(sc)) {
244                 hdr->flags |= ISCSI_FLAG_CMD_READ;
245                 rc = iscsi_prep_bidi_ahs(ctask);
246                 if (rc)
247                         return rc;
248         }
249         if (sc->sc_data_direction == DMA_TO_DEVICE) {
250                 unsigned out_len = scsi_out(sc)->length;
251                 hdr->data_length = cpu_to_be32(out_len);
252                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
253                 /*
254                  * Write counters:
255                  *
256                  *      imm_count       bytes to be sent right after
257                  *                      SCSI PDU Header
258                  *
259                  *      unsol_count     bytes(as Data-Out) to be sent
260                  *                      without R2T ack right after
261                  *                      immediate data
262                  *
263                  *      r2t_data_count  bytes to be sent via R2T ack's
264                  *
265                  *      pad_count       bytes to be sent as zero-padding
266                  */
267                 ctask->unsol_count = 0;
268                 ctask->unsol_offset = 0;
269                 ctask->unsol_datasn = 0;
270
271                 if (session->imm_data_en) {
272                         if (out_len >= session->first_burst)
273                                 ctask->imm_count = min(session->first_burst,
274                                                         conn->max_xmit_dlength);
275                         else
276                                 ctask->imm_count = min(out_len,
277                                                         conn->max_xmit_dlength);
278                         hton24(hdr->dlength, ctask->imm_count);
279                 } else
280                         zero_data(hdr->dlength);
281
282                 if (!session->initial_r2t_en) {
283                         ctask->unsol_count = min(session->first_burst, out_len)
284                                                              - ctask->imm_count;
285                         ctask->unsol_offset = ctask->imm_count;
286                 }
287
288                 if (!ctask->unsol_count)
289                         /* No unsolicit Data-Out's */
290                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
291         } else {
292                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
293                 zero_data(hdr->dlength);
294                 hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
295
296                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
297                         hdr->flags |= ISCSI_FLAG_CMD_READ;
298         }
299
300         /* calculate size of additional header segments (AHSs) */
301         hdrlength = ctask->hdr_len - sizeof(*hdr);
302
303         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
304         hdrlength /= ISCSI_PAD_LEN;
305
306         WARN_ON(hdrlength >= 256);
307         hdr->hlength = hdrlength & 0xFF;
308
309         if (conn->session->tt->init_cmd_task(conn->ctask))
310                 return EIO;
311
312         conn->scsicmd_pdus_cnt++;
313         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x "
314                 "len %d bidi_len %d cmdsn %d win %d]\n",
315                 scsi_bidi_cmnd(sc) ? "bidirectional" :
316                      sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
317                 conn->id, sc, sc->cmnd[0], ctask->itt,
318                 scsi_bufflen(sc), scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
319                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
320         return 0;
321 }
322
323 /**
324  * iscsi_complete_command - return command back to scsi-ml
325  * @ctask: iscsi cmd task
326  *
327  * Must be called with session lock.
328  * This function returns the scsi command to scsi-ml and returns
329  * the cmd task to the pool of available cmd tasks.
330  */
331 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
332 {
333         struct iscsi_conn *conn = ctask->conn;
334         struct iscsi_session *session = conn->session;
335         struct scsi_cmnd *sc = ctask->sc;
336
337         ctask->state = ISCSI_TASK_COMPLETED;
338         ctask->sc = NULL;
339         /* SCSI eh reuses commands to verify us */
340         sc->SCp.ptr = NULL;
341         if (conn->ctask == ctask)
342                 conn->ctask = NULL;
343         list_del_init(&ctask->running);
344         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
345         sc->scsi_done(sc);
346 }
347
348 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
349 {
350         atomic_inc(&ctask->refcount);
351 }
352
353 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
354 {
355         if (atomic_dec_and_test(&ctask->refcount))
356                 iscsi_complete_command(ctask);
357 }
358
359 /*
360  * session lock must be held
361  */
362 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
363                          int err)
364 {
365         struct scsi_cmnd *sc;
366
367         sc = ctask->sc;
368         if (!sc)
369                 return;
370
371         if (ctask->state == ISCSI_TASK_PENDING)
372                 /*
373                  * cmd never made it to the xmit thread, so we should not count
374                  * the cmd in the sequencing
375                  */
376                 conn->session->queued_cmdsn--;
377         else
378                 conn->session->tt->cleanup_cmd_task(conn, ctask);
379
380         sc->result = err;
381         if (!scsi_bidi_cmnd(sc))
382                 scsi_set_resid(sc, scsi_bufflen(sc));
383         else {
384                 scsi_out(sc)->resid = scsi_out(sc)->length;
385                 scsi_in(sc)->resid = scsi_in(sc)->length;
386         }
387         if (conn->ctask == ctask)
388                 conn->ctask = NULL;
389         /* release ref from queuecommand */
390         __iscsi_put_ctask(ctask);
391 }
392
393 /**
394  * iscsi_free_mgmt_task - return mgmt task back to pool
395  * @conn: iscsi connection
396  * @mtask: mtask
397  *
398  * Must be called with session lock.
399  */
400 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
401                           struct iscsi_mgmt_task *mtask)
402 {
403         list_del_init(&mtask->running);
404         if (conn->login_mtask == mtask)
405                 return;
406
407         if (conn->ping_mtask == mtask)
408                 conn->ping_mtask = NULL;
409         __kfifo_put(conn->session->mgmtpool.queue,
410                     (void*)&mtask, sizeof(void*));
411 }
412 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
413
414 static struct iscsi_mgmt_task *
415 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
416                       char *data, uint32_t data_size)
417 {
418         struct iscsi_session *session = conn->session;
419         struct iscsi_mgmt_task *mtask;
420
421         if (session->state == ISCSI_STATE_TERMINATE)
422                 return NULL;
423
424         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
425             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
426                 /*
427                  * Login and Text are sent serially, in
428                  * request-followed-by-response sequence.
429                  * Same mtask can be used. Same ITT must be used.
430                  * Note that login_mtask is preallocated at conn_create().
431                  */
432                 mtask = conn->login_mtask;
433         else {
434                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
435                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
436
437                 if (!__kfifo_get(session->mgmtpool.queue,
438                                  (void*)&mtask, sizeof(void*)))
439                         return NULL;
440         }
441
442         if (data_size) {
443                 memcpy(mtask->data, data, data_size);
444                 mtask->data_count = data_size;
445         } else
446                 mtask->data_count = 0;
447
448         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
449         INIT_LIST_HEAD(&mtask->running);
450         list_add_tail(&mtask->running, &conn->mgmtqueue);
451         return mtask;
452 }
453
454 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
455                         char *data, uint32_t data_size)
456 {
457         struct iscsi_conn *conn = cls_conn->dd_data;
458         struct iscsi_session *session = conn->session;
459         int err = 0;
460
461         spin_lock_bh(&session->lock);
462         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
463                 err = -EPERM;
464         spin_unlock_bh(&session->lock);
465         scsi_queue_work(session->host, &conn->xmitwork);
466         return err;
467 }
468 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
469
470 /**
471  * iscsi_cmd_rsp - SCSI Command Response processing
472  * @conn: iscsi connection
473  * @hdr: iscsi header
474  * @ctask: scsi command task
475  * @data: cmd data buffer
476  * @datalen: len of buffer
477  *
478  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
479  * then completes the command and task.
480  **/
481 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
482                                struct iscsi_cmd_task *ctask, char *data,
483                                int datalen)
484 {
485         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
486         struct iscsi_session *session = conn->session;
487         struct scsi_cmnd *sc = ctask->sc;
488
489         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
490         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
491
492         sc->result = (DID_OK << 16) | rhdr->cmd_status;
493
494         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
495                 sc->result = DID_ERROR << 16;
496                 goto out;
497         }
498
499         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
500                 uint16_t senselen;
501
502                 if (datalen < 2) {
503 invalid_datalen:
504                         iscsi_conn_printk(KERN_ERR,  conn,
505                                          "Got CHECK_CONDITION but invalid data "
506                                          "buffer size of %d\n", datalen);
507                         sc->result = DID_BAD_TARGET << 16;
508                         goto out;
509                 }
510
511                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
512                 if (datalen < senselen)
513                         goto invalid_datalen;
514
515                 memcpy(sc->sense_buffer, data + 2,
516                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
517                 debug_scsi("copied %d bytes of sense\n",
518                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
519         }
520
521         if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
522                            ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
523                 int res_count = be32_to_cpu(rhdr->bi_residual_count);
524
525                 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
526                                 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
527                                  res_count <= scsi_in(sc)->length))
528                         scsi_in(sc)->resid = res_count;
529                 else
530                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
531         }
532
533         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
534                            ISCSI_FLAG_CMD_OVERFLOW)) {
535                 int res_count = be32_to_cpu(rhdr->residual_count);
536
537                 if (res_count > 0 &&
538                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
539                      res_count <= scsi_bufflen(sc)))
540                         /* write side for bidi or uni-io set_resid */
541                         scsi_set_resid(sc, res_count);
542                 else
543                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
544         }
545 out:
546         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
547                    (long)sc, sc->result, ctask->itt);
548         conn->scsirsp_pdus_cnt++;
549
550         __iscsi_put_ctask(ctask);
551 }
552
553 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
554 {
555         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
556
557         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
558         conn->tmfrsp_pdus_cnt++;
559
560         if (conn->tmf_state != TMF_QUEUED)
561                 return;
562
563         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
564                 conn->tmf_state = TMF_SUCCESS;
565         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
566                 conn->tmf_state = TMF_NOT_FOUND;
567         else
568                 conn->tmf_state = TMF_FAILED;
569         wake_up(&conn->ehwait);
570 }
571
572 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
573 {
574         struct iscsi_nopout hdr;
575         struct iscsi_mgmt_task *mtask;
576
577         if (!rhdr && conn->ping_mtask)
578                 return;
579
580         memset(&hdr, 0, sizeof(struct iscsi_nopout));
581         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
582         hdr.flags = ISCSI_FLAG_CMD_FINAL;
583
584         if (rhdr) {
585                 memcpy(hdr.lun, rhdr->lun, 8);
586                 hdr.ttt = rhdr->ttt;
587                 hdr.itt = RESERVED_ITT;
588         } else
589                 hdr.ttt = RESERVED_ITT;
590
591         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
592         if (!mtask) {
593                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
594                 return;
595         }
596
597         /* only track our nops */
598         if (!rhdr) {
599                 conn->ping_mtask = mtask;
600                 conn->last_ping = jiffies;
601         }
602         scsi_queue_work(conn->session->host, &conn->xmitwork);
603 }
604
605 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
606                                char *data, int datalen)
607 {
608         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
609         struct iscsi_hdr rejected_pdu;
610         uint32_t itt;
611
612         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
613
614         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
615                 if (ntoh24(reject->dlength) > datalen)
616                         return ISCSI_ERR_PROTO;
617
618                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
619                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
620                         itt = get_itt(rejected_pdu.itt);
621                         iscsi_conn_printk(KERN_ERR, conn,
622                                           "itt 0x%x had pdu (op 0x%x) rejected "
623                                           "due to DataDigest error.\n", itt,
624                                           rejected_pdu.opcode);
625                 }
626         }
627         return 0;
628 }
629
630 /**
631  * __iscsi_complete_pdu - complete pdu
632  * @conn: iscsi conn
633  * @hdr: iscsi header
634  * @data: data buffer
635  * @datalen: len of data buffer
636  *
637  * Completes pdu processing by freeing any resources allocated at
638  * queuecommand or send generic. session lock must be held and verify
639  * itt must have been called.
640  */
641 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
642                                 char *data, int datalen)
643 {
644         struct iscsi_session *session = conn->session;
645         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
646         struct iscsi_cmd_task *ctask;
647         struct iscsi_mgmt_task *mtask;
648         uint32_t itt;
649
650         conn->last_recv = jiffies;
651         if (hdr->itt != RESERVED_ITT)
652                 itt = get_itt(hdr->itt);
653         else
654                 itt = ~0U;
655
656         if (itt < session->cmds_max) {
657                 ctask = session->cmds[itt];
658
659                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
660                            opcode, conn->id, ctask->itt, datalen);
661
662                 switch(opcode) {
663                 case ISCSI_OP_SCSI_CMD_RSP:
664                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
665                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
666                                            datalen);
667                         break;
668                 case ISCSI_OP_SCSI_DATA_IN:
669                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
670                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
671                                 conn->scsirsp_pdus_cnt++;
672                                 __iscsi_put_ctask(ctask);
673                         }
674                         break;
675                 case ISCSI_OP_R2T:
676                         /* LLD handles this for now */
677                         break;
678                 default:
679                         rc = ISCSI_ERR_BAD_OPCODE;
680                         break;
681                 }
682         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
683                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
684                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
685
686                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
687                            opcode, conn->id, mtask->itt, datalen);
688
689                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
690                 switch(opcode) {
691                 case ISCSI_OP_LOGOUT_RSP:
692                         if (datalen) {
693                                 rc = ISCSI_ERR_PROTO;
694                                 break;
695                         }
696                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
697                         /* fall through */
698                 case ISCSI_OP_LOGIN_RSP:
699                 case ISCSI_OP_TEXT_RSP:
700                         /*
701                          * login related PDU's exp_statsn is handled in
702                          * userspace
703                          */
704                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
705                                 rc = ISCSI_ERR_CONN_FAILED;
706                         iscsi_free_mgmt_task(conn, mtask);
707                         break;
708                 case ISCSI_OP_SCSI_TMFUNC_RSP:
709                         if (datalen) {
710                                 rc = ISCSI_ERR_PROTO;
711                                 break;
712                         }
713
714                         iscsi_tmf_rsp(conn, hdr);
715                         iscsi_free_mgmt_task(conn, mtask);
716                         break;
717                 case ISCSI_OP_NOOP_IN:
718                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
719                             datalen) {
720                                 rc = ISCSI_ERR_PROTO;
721                                 break;
722                         }
723                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
724
725                         if (conn->ping_mtask != mtask) {
726                                 /*
727                                  * If this is not in response to one of our
728                                  * nops then it must be from userspace.
729                                  */
730                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
731                                                    datalen))
732                                         rc = ISCSI_ERR_CONN_FAILED;
733                         } else
734                                 mod_timer(&conn->transport_timer,
735                                           jiffies + conn->recv_timeout);
736                         iscsi_free_mgmt_task(conn, mtask);
737                         break;
738                 default:
739                         rc = ISCSI_ERR_BAD_OPCODE;
740                         break;
741                 }
742         } else if (itt == ~0U) {
743                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
744
745                 switch(opcode) {
746                 case ISCSI_OP_NOOP_IN:
747                         if (datalen) {
748                                 rc = ISCSI_ERR_PROTO;
749                                 break;
750                         }
751
752                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
753                                 break;
754
755                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
756                         break;
757                 case ISCSI_OP_REJECT:
758                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
759                         break;
760                 case ISCSI_OP_ASYNC_EVENT:
761                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
762                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
763                                 rc = ISCSI_ERR_CONN_FAILED;
764                         break;
765                 default:
766                         rc = ISCSI_ERR_BAD_OPCODE;
767                         break;
768                 }
769         } else
770                 rc = ISCSI_ERR_BAD_ITT;
771
772         return rc;
773 }
774
775 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
776                        char *data, int datalen)
777 {
778         int rc;
779
780         spin_lock(&conn->session->lock);
781         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
782         spin_unlock(&conn->session->lock);
783         return rc;
784 }
785 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
786
787 /* verify itt (itt encoding: age+cid+itt) */
788 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
789                      uint32_t *ret_itt)
790 {
791         struct iscsi_session *session = conn->session;
792         struct iscsi_cmd_task *ctask;
793         uint32_t itt;
794
795         if (hdr->itt != RESERVED_ITT) {
796                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
797                     (session->age << ISCSI_AGE_SHIFT)) {
798                         iscsi_conn_printk(KERN_ERR, conn,
799                                           "received itt %x expected session "
800                                           "age (%x)\n", (__force u32)hdr->itt,
801                                           session->age & ISCSI_AGE_MASK);
802                         return ISCSI_ERR_BAD_ITT;
803                 }
804
805                 itt = get_itt(hdr->itt);
806         } else
807                 itt = ~0U;
808
809         if (itt < session->cmds_max) {
810                 ctask = session->cmds[itt];
811
812                 if (!ctask->sc) {
813                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
814                                           "with itt 0x%x\n", ctask->itt);
815                         /* force drop */
816                         return ISCSI_ERR_NO_SCSI_CMD;
817                 }
818
819                 if (ctask->sc->SCp.phase != session->age) {
820                         iscsi_conn_printk(KERN_ERR, conn,
821                                           "iscsi: ctask's session age %d, "
822                                           "expected %d\n", ctask->sc->SCp.phase,
823                                           session->age);
824                         return ISCSI_ERR_SESSION_FAILED;
825                 }
826         }
827
828         *ret_itt = itt;
829         return 0;
830 }
831 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
832
833 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
834 {
835         struct iscsi_session *session = conn->session;
836         unsigned long flags;
837
838         spin_lock_irqsave(&session->lock, flags);
839         if (session->state == ISCSI_STATE_FAILED) {
840                 spin_unlock_irqrestore(&session->lock, flags);
841                 return;
842         }
843
844         if (conn->stop_stage == 0)
845                 session->state = ISCSI_STATE_FAILED;
846         spin_unlock_irqrestore(&session->lock, flags);
847         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
848         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
849         iscsi_conn_error(conn->cls_conn, err);
850 }
851 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
852
853 static void iscsi_prep_mtask(struct iscsi_conn *conn,
854                              struct iscsi_mgmt_task *mtask)
855 {
856         struct iscsi_session *session = conn->session;
857         struct iscsi_hdr *hdr = mtask->hdr;
858         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
859
860         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
861             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
862                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
863         /*
864          * pre-format CmdSN for outgoing PDU.
865          */
866         nop->cmdsn = cpu_to_be32(session->cmdsn);
867         if (hdr->itt != RESERVED_ITT) {
868                 hdr->itt = build_itt(mtask->itt, session->age);
869                 /*
870                  * TODO: We always use immediate, so we never hit this.
871                  * If we start to send tmfs or nops as non-immediate then
872                  * we should start checking the cmdsn numbers for mgmt tasks.
873                  */
874                 if (conn->c_stage == ISCSI_CONN_STARTED &&
875                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
876                         session->queued_cmdsn++;
877                         session->cmdsn++;
878                 }
879         }
880
881         if (session->tt->init_mgmt_task)
882                 session->tt->init_mgmt_task(conn, mtask);
883
884         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
885                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
886                    mtask->data_count);
887 }
888
889 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
890 {
891         struct iscsi_hdr *hdr = conn->mtask->hdr;
892         int rc;
893
894         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
895                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
896         spin_unlock_bh(&conn->session->lock);
897
898         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
899         spin_lock_bh(&conn->session->lock);
900         if (rc)
901                 return rc;
902
903         /* done with this in-progress mtask */
904         conn->mtask = NULL;
905         return 0;
906 }
907
908 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
909 {
910         struct iscsi_session *session = conn->session;
911
912         /*
913          * Check for iSCSI window and take care of CmdSN wrap-around
914          */
915         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
916                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
917                            "CmdSN %u/%u\n", session->exp_cmdsn,
918                            session->max_cmdsn, session->cmdsn,
919                            session->queued_cmdsn);
920                 return -ENOSPC;
921         }
922         return 0;
923 }
924
925 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
926 {
927         struct iscsi_cmd_task *ctask = conn->ctask;
928         int rc;
929
930         __iscsi_get_ctask(ctask);
931         spin_unlock_bh(&conn->session->lock);
932         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
933         spin_lock_bh(&conn->session->lock);
934         __iscsi_put_ctask(ctask);
935         if (!rc)
936                 /* done with this ctask */
937                 conn->ctask = NULL;
938         return rc;
939 }
940
941 /**
942  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
943  * @ctask: ctask to requeue
944  *
945  * LLDs that need to run a ctask from the session workqueue should call
946  * this. The session lock must be held.
947  */
948 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
949 {
950         struct iscsi_conn *conn = ctask->conn;
951
952         list_move_tail(&ctask->running, &conn->requeue);
953         scsi_queue_work(conn->session->host, &conn->xmitwork);
954 }
955 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
956
957 /**
958  * iscsi_data_xmit - xmit any command into the scheduled connection
959  * @conn: iscsi connection
960  *
961  * Notes:
962  *      The function can return -EAGAIN in which case the caller must
963  *      re-schedule it again later or recover. '0' return code means
964  *      successful xmit.
965  **/
966 static int iscsi_data_xmit(struct iscsi_conn *conn)
967 {
968         int rc = 0;
969
970         spin_lock_bh(&conn->session->lock);
971         if (unlikely(conn->suspend_tx)) {
972                 debug_scsi("conn %d Tx suspended!\n", conn->id);
973                 spin_unlock_bh(&conn->session->lock);
974                 return -ENODATA;
975         }
976
977         if (conn->ctask) {
978                 rc = iscsi_xmit_ctask(conn);
979                 if (rc)
980                         goto again;
981         }
982
983         if (conn->mtask) {
984                 rc = iscsi_xmit_mtask(conn);
985                 if (rc)
986                         goto again;
987         }
988
989         /*
990          * process mgmt pdus like nops before commands since we should
991          * only have one nop-out as a ping from us and targets should not
992          * overflow us with nop-ins
993          */
994 check_mgmt:
995         while (!list_empty(&conn->mgmtqueue)) {
996                 conn->mtask = list_entry(conn->mgmtqueue.next,
997                                          struct iscsi_mgmt_task, running);
998                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
999                         iscsi_free_mgmt_task(conn, conn->mtask);
1000                         conn->mtask = NULL;
1001                         continue;
1002                 }
1003
1004                 iscsi_prep_mtask(conn, conn->mtask);
1005                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
1006                 rc = iscsi_xmit_mtask(conn);
1007                 if (rc)
1008                         goto again;
1009         }
1010
1011         /* process pending command queue */
1012         while (!list_empty(&conn->xmitqueue)) {
1013                 if (conn->tmf_state == TMF_QUEUED)
1014                         break;
1015
1016                 conn->ctask = list_entry(conn->xmitqueue.next,
1017                                          struct iscsi_cmd_task, running);
1018                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1019                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
1020                         continue;
1021                 }
1022                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
1023                         fail_command(conn, conn->ctask, DID_ABORT << 16);
1024                         continue;
1025                 }
1026
1027                 conn->ctask->state = ISCSI_TASK_RUNNING;
1028                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
1029                 rc = iscsi_xmit_ctask(conn);
1030                 if (rc)
1031                         goto again;
1032                 /*
1033                  * we could continuously get new ctask requests so
1034                  * we need to check the mgmt queue for nops that need to
1035                  * be sent to aviod starvation
1036                  */
1037                 if (!list_empty(&conn->mgmtqueue))
1038                         goto check_mgmt;
1039         }
1040
1041         while (!list_empty(&conn->requeue)) {
1042                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
1043                         break;
1044
1045                 /*
1046                  * we always do fastlogout - conn stop code will clean up.
1047                  */
1048                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1049                         break;
1050
1051                 conn->ctask = list_entry(conn->requeue.next,
1052                                          struct iscsi_cmd_task, running);
1053                 conn->ctask->state = ISCSI_TASK_RUNNING;
1054                 list_move_tail(conn->requeue.next, &conn->run_list);
1055                 rc = iscsi_xmit_ctask(conn);
1056                 if (rc)
1057                         goto again;
1058                 if (!list_empty(&conn->mgmtqueue))
1059                         goto check_mgmt;
1060         }
1061         spin_unlock_bh(&conn->session->lock);
1062         return -ENODATA;
1063
1064 again:
1065         if (unlikely(conn->suspend_tx))
1066                 rc = -ENODATA;
1067         spin_unlock_bh(&conn->session->lock);
1068         return rc;
1069 }
1070
1071 static void iscsi_xmitworker(struct work_struct *work)
1072 {
1073         struct iscsi_conn *conn =
1074                 container_of(work, struct iscsi_conn, xmitwork);
1075         int rc;
1076         /*
1077          * serialize Xmit worker on a per-connection basis.
1078          */
1079         do {
1080                 rc = iscsi_data_xmit(conn);
1081         } while (rc >= 0 || rc == -EAGAIN);
1082 }
1083
1084 enum {
1085         FAILURE_BAD_HOST = 1,
1086         FAILURE_SESSION_FAILED,
1087         FAILURE_SESSION_FREED,
1088         FAILURE_WINDOW_CLOSED,
1089         FAILURE_OOM,
1090         FAILURE_SESSION_TERMINATE,
1091         FAILURE_SESSION_IN_RECOVERY,
1092         FAILURE_SESSION_RECOVERY_TIMEOUT,
1093         FAILURE_SESSION_LOGGING_OUT,
1094         FAILURE_SESSION_NOT_READY,
1095 };
1096
1097 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1098 {
1099         struct Scsi_Host *host;
1100         int reason = 0;
1101         struct iscsi_session *session;
1102         struct iscsi_conn *conn;
1103         struct iscsi_cmd_task *ctask = NULL;
1104
1105         sc->scsi_done = done;
1106         sc->result = 0;
1107         sc->SCp.ptr = NULL;
1108
1109         host = sc->device->host;
1110         spin_unlock(host->host_lock);
1111
1112         session = iscsi_hostdata(host->hostdata);
1113         spin_lock(&session->lock);
1114
1115         reason = iscsi_session_chkready(session_to_cls(session));
1116         if (reason) {
1117                 sc->result = reason;
1118                 goto fault;
1119         }
1120
1121         /*
1122          * ISCSI_STATE_FAILED is a temp. state. The recovery
1123          * code will decide what is best to do with command queued
1124          * during this time
1125          */
1126         if (session->state != ISCSI_STATE_LOGGED_IN &&
1127             session->state != ISCSI_STATE_FAILED) {
1128                 /*
1129                  * to handle the race between when we set the recovery state
1130                  * and block the session we requeue here (commands could
1131                  * be entering our queuecommand while a block is starting
1132                  * up because the block code is not locked)
1133                  */
1134                 switch (session->state) {
1135                 case ISCSI_STATE_IN_RECOVERY:
1136                         reason = FAILURE_SESSION_IN_RECOVERY;
1137                         sc->result = DID_IMM_RETRY << 16;
1138                         break;
1139                 case ISCSI_STATE_LOGGING_OUT:
1140                         reason = FAILURE_SESSION_LOGGING_OUT;
1141                         sc->result = DID_IMM_RETRY << 16;
1142                         break;
1143                 case ISCSI_STATE_RECOVERY_FAILED:
1144                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1145                         sc->result = DID_NO_CONNECT << 16;
1146                         break;
1147                 case ISCSI_STATE_TERMINATE:
1148                         reason = FAILURE_SESSION_TERMINATE;
1149                         sc->result = DID_NO_CONNECT << 16;
1150                         break;
1151                 default:
1152                         reason = FAILURE_SESSION_FREED;
1153                         sc->result = DID_NO_CONNECT << 16;
1154                 }
1155                 goto fault;
1156         }
1157
1158         conn = session->leadconn;
1159         if (!conn) {
1160                 reason = FAILURE_SESSION_FREED;
1161                 sc->result = DID_NO_CONNECT << 16;
1162                 goto fault;
1163         }
1164
1165         if (iscsi_check_cmdsn_window_closed(conn)) {
1166                 reason = FAILURE_WINDOW_CLOSED;
1167                 goto reject;
1168         }
1169
1170         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1171                          sizeof(void*))) {
1172                 reason = FAILURE_OOM;
1173                 goto reject;
1174         }
1175         session->queued_cmdsn++;
1176
1177         sc->SCp.phase = session->age;
1178         sc->SCp.ptr = (char *)ctask;
1179
1180         atomic_set(&ctask->refcount, 1);
1181         ctask->state = ISCSI_TASK_PENDING;
1182         ctask->conn = conn;
1183         ctask->sc = sc;
1184         INIT_LIST_HEAD(&ctask->running);
1185
1186         list_add_tail(&ctask->running, &conn->xmitqueue);
1187         spin_unlock(&session->lock);
1188
1189         scsi_queue_work(host, &conn->xmitwork);
1190         spin_lock(host->host_lock);
1191         return 0;
1192
1193 reject:
1194         spin_unlock(&session->lock);
1195         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1196         spin_lock(host->host_lock);
1197         return SCSI_MLQUEUE_HOST_BUSY;
1198
1199 fault:
1200         spin_unlock(&session->lock);
1201         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1202         if (!scsi_bidi_cmnd(sc))
1203                 scsi_set_resid(sc, scsi_bufflen(sc));
1204         else {
1205                 scsi_out(sc)->resid = scsi_out(sc)->length;
1206                 scsi_in(sc)->resid = scsi_in(sc)->length;
1207         }
1208         sc->scsi_done(sc);
1209         spin_lock(host->host_lock);
1210         return 0;
1211 }
1212 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1213
1214 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1215 {
1216         if (depth > ISCSI_MAX_CMD_PER_LUN)
1217                 depth = ISCSI_MAX_CMD_PER_LUN;
1218         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1219         return sdev->queue_depth;
1220 }
1221 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1222
1223 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1224 {
1225         struct iscsi_session *session = class_to_transport_session(cls_session);
1226
1227         spin_lock_bh(&session->lock);
1228         if (session->state != ISCSI_STATE_LOGGED_IN) {
1229                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1230                 if (session->leadconn)
1231                         wake_up(&session->leadconn->ehwait);
1232         }
1233         spin_unlock_bh(&session->lock);
1234 }
1235 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1236
1237 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1238 {
1239         struct Scsi_Host *host = sc->device->host;
1240         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1241         struct iscsi_conn *conn = session->leadconn;
1242
1243         mutex_lock(&session->eh_mutex);
1244         spin_lock_bh(&session->lock);
1245         if (session->state == ISCSI_STATE_TERMINATE) {
1246 failed:
1247                 debug_scsi("failing host reset: session terminated "
1248                            "[CID %d age %d]\n", conn->id, session->age);
1249                 spin_unlock_bh(&session->lock);
1250                 mutex_unlock(&session->eh_mutex);
1251                 return FAILED;
1252         }
1253
1254         spin_unlock_bh(&session->lock);
1255         mutex_unlock(&session->eh_mutex);
1256         /*
1257          * we drop the lock here but the leadconn cannot be destoyed while
1258          * we are in the scsi eh
1259          */
1260         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1261
1262         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1263         wait_event_interruptible(conn->ehwait,
1264                                  session->state == ISCSI_STATE_TERMINATE ||
1265                                  session->state == ISCSI_STATE_LOGGED_IN ||
1266                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1267         if (signal_pending(current))
1268                 flush_signals(current);
1269
1270         mutex_lock(&session->eh_mutex);
1271         spin_lock_bh(&session->lock);
1272         if (session->state == ISCSI_STATE_LOGGED_IN)
1273                 iscsi_session_printk(KERN_INFO, session,
1274                                      "host reset succeeded\n");
1275         else
1276                 goto failed;
1277         spin_unlock_bh(&session->lock);
1278         mutex_unlock(&session->eh_mutex);
1279         return SUCCESS;
1280 }
1281 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1282
1283 static void iscsi_tmf_timedout(unsigned long data)
1284 {
1285         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1286         struct iscsi_session *session = conn->session;
1287
1288         spin_lock(&session->lock);
1289         if (conn->tmf_state == TMF_QUEUED) {
1290                 conn->tmf_state = TMF_TIMEDOUT;
1291                 debug_scsi("tmf timedout\n");
1292                 /* unblock eh_abort() */
1293                 wake_up(&conn->ehwait);
1294         }
1295         spin_unlock(&session->lock);
1296 }
1297
1298 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1299                                    struct iscsi_tm *hdr, int age,
1300                                    int timeout)
1301 {
1302         struct iscsi_session *session = conn->session;
1303         struct iscsi_mgmt_task *mtask;
1304
1305         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1306                                       NULL, 0);
1307         if (!mtask) {
1308                 spin_unlock_bh(&session->lock);
1309                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1310                 spin_lock_bh(&session->lock);
1311                 debug_scsi("tmf exec failure\n");
1312                 return -EPERM;
1313         }
1314         conn->tmfcmd_pdus_cnt++;
1315         conn->tmf_timer.expires = timeout * HZ + jiffies;
1316         conn->tmf_timer.function = iscsi_tmf_timedout;
1317         conn->tmf_timer.data = (unsigned long)conn;
1318         add_timer(&conn->tmf_timer);
1319         debug_scsi("tmf set timeout\n");
1320
1321         spin_unlock_bh(&session->lock);
1322         mutex_unlock(&session->eh_mutex);
1323         scsi_queue_work(session->host, &conn->xmitwork);
1324
1325         /*
1326          * block eh thread until:
1327          *
1328          * 1) tmf response
1329          * 2) tmf timeout
1330          * 3) session is terminated or restarted or userspace has
1331          * given up on recovery
1332          */
1333         wait_event_interruptible(conn->ehwait, age != session->age ||
1334                                  session->state != ISCSI_STATE_LOGGED_IN ||
1335                                  conn->tmf_state != TMF_QUEUED);
1336         if (signal_pending(current))
1337                 flush_signals(current);
1338         del_timer_sync(&conn->tmf_timer);
1339
1340         mutex_lock(&session->eh_mutex);
1341         spin_lock_bh(&session->lock);
1342         /* if the session drops it will clean up the mtask */
1343         if (age != session->age ||
1344             session->state != ISCSI_STATE_LOGGED_IN)
1345                 return -ENOTCONN;
1346         return 0;
1347 }
1348
1349 /*
1350  * Fail commands. session lock held and recv side suspended and xmit
1351  * thread flushed
1352  */
1353 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1354                               int error)
1355 {
1356         struct iscsi_cmd_task *ctask, *tmp;
1357
1358         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1359                 conn->ctask = NULL;
1360
1361         /* flush pending */
1362         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1363                 if (lun == ctask->sc->device->lun || lun == -1) {
1364                         debug_scsi("failing pending sc %p itt 0x%x\n",
1365                                    ctask->sc, ctask->itt);
1366                         fail_command(conn, ctask, error << 16);
1367                 }
1368         }
1369
1370         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1371                 if (lun == ctask->sc->device->lun || lun == -1) {
1372                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1373                                    ctask->sc, ctask->itt);
1374                         fail_command(conn, ctask, error << 16);
1375                 }
1376         }
1377
1378         /* fail all other running */
1379         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1380                 if (lun == ctask->sc->device->lun || lun == -1) {
1381                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1382                                    ctask->sc, ctask->itt);
1383                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1384                 }
1385         }
1386 }
1387
1388 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1389 {
1390         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1391         scsi_flush_work(conn->session->host);
1392 }
1393
1394 static void iscsi_start_tx(struct iscsi_conn *conn)
1395 {
1396         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1397         scsi_queue_work(conn->session->host, &conn->xmitwork);
1398 }
1399
1400 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1401 {
1402         struct iscsi_cls_session *cls_session;
1403         struct iscsi_session *session;
1404         struct iscsi_conn *conn;
1405         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1406
1407         cls_session = starget_to_session(scsi_target(scmd->device));
1408         session = class_to_transport_session(cls_session);
1409
1410         debug_scsi("scsi cmd %p timedout\n", scmd);
1411
1412         spin_lock(&session->lock);
1413         if (session->state != ISCSI_STATE_LOGGED_IN) {
1414                 /*
1415                  * We are probably in the middle of iscsi recovery so let
1416                  * that complete and handle the error.
1417                  */
1418                 rc = EH_RESET_TIMER;
1419                 goto done;
1420         }
1421
1422         conn = session->leadconn;
1423         if (!conn) {
1424                 /* In the middle of shuting down */
1425                 rc = EH_RESET_TIMER;
1426                 goto done;
1427         }
1428
1429         if (!conn->recv_timeout && !conn->ping_timeout)
1430                 goto done;
1431         /*
1432          * if the ping timedout then we are in the middle of cleaning up
1433          * and can let the iscsi eh handle it
1434          */
1435         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1436                             (conn->ping_timeout * HZ), jiffies))
1437                 rc = EH_RESET_TIMER;
1438         /*
1439          * if we are about to check the transport then give the command
1440          * more time
1441          */
1442         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1443                            jiffies))
1444                 rc = EH_RESET_TIMER;
1445         /* if in the middle of checking the transport then give us more time */
1446         if (conn->ping_mtask)
1447                 rc = EH_RESET_TIMER;
1448 done:
1449         spin_unlock(&session->lock);
1450         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1451         return rc;
1452 }
1453
1454 static void iscsi_check_transport_timeouts(unsigned long data)
1455 {
1456         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1457         struct iscsi_session *session = conn->session;
1458         unsigned long recv_timeout, next_timeout = 0, last_recv;
1459
1460         spin_lock(&session->lock);
1461         if (session->state != ISCSI_STATE_LOGGED_IN)
1462                 goto done;
1463
1464         recv_timeout = conn->recv_timeout;
1465         if (!recv_timeout)
1466                 goto done;
1467
1468         recv_timeout *= HZ;
1469         last_recv = conn->last_recv;
1470         if (conn->ping_mtask &&
1471             time_before_eq(conn->last_ping + (conn->ping_timeout * HZ),
1472                            jiffies)) {
1473                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1474                                   "expired, last rx %lu, last ping %lu, "
1475                                   "now %lu\n", conn->ping_timeout, last_recv,
1476                                   conn->last_ping, jiffies);
1477                 spin_unlock(&session->lock);
1478                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1479                 return;
1480         }
1481
1482         if (time_before_eq(last_recv + recv_timeout, jiffies)) {
1483                 /* send a ping to try to provoke some traffic */
1484                 debug_scsi("Sending nopout as ping on conn %p\n", conn);
1485                 iscsi_send_nopout(conn, NULL);
1486                 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
1487         } else
1488                 next_timeout = last_recv + recv_timeout;
1489
1490         debug_scsi("Setting next tmo %lu\n", next_timeout);
1491         mod_timer(&conn->transport_timer, next_timeout);
1492 done:
1493         spin_unlock(&session->lock);
1494 }
1495
1496 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1497                                       struct iscsi_tm *hdr)
1498 {
1499         memset(hdr, 0, sizeof(*hdr));
1500         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1501         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1502         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1503         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1504         hdr->rtt = ctask->hdr->itt;
1505         hdr->refcmdsn = ctask->hdr->cmdsn;
1506 }
1507
1508 int iscsi_eh_abort(struct scsi_cmnd *sc)
1509 {
1510         struct Scsi_Host *host = sc->device->host;
1511         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1512         struct iscsi_conn *conn;
1513         struct iscsi_cmd_task *ctask;
1514         struct iscsi_tm *hdr;
1515         int rc, age;
1516
1517         mutex_lock(&session->eh_mutex);
1518         spin_lock_bh(&session->lock);
1519         /*
1520          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1521          * got the command.
1522          */
1523         if (!sc->SCp.ptr) {
1524                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1525                 spin_unlock_bh(&session->lock);
1526                 mutex_unlock(&session->eh_mutex);
1527                 return SUCCESS;
1528         }
1529
1530         /*
1531          * If we are not logged in or we have started a new session
1532          * then let the host reset code handle this
1533          */
1534         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1535             sc->SCp.phase != session->age) {
1536                 spin_unlock_bh(&session->lock);
1537                 mutex_unlock(&session->eh_mutex);
1538                 return FAILED;
1539         }
1540
1541         conn = session->leadconn;
1542         conn->eh_abort_cnt++;
1543         age = session->age;
1544
1545         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1546         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1547
1548         /* ctask completed before time out */
1549         if (!ctask->sc) {
1550                 debug_scsi("sc completed while abort in progress\n");
1551                 goto success;
1552         }
1553
1554         if (ctask->state == ISCSI_TASK_PENDING) {
1555                 fail_command(conn, ctask, DID_ABORT << 16);
1556                 goto success;
1557         }
1558
1559         /* only have one tmf outstanding at a time */
1560         if (conn->tmf_state != TMF_INITIAL)
1561                 goto failed;
1562         conn->tmf_state = TMF_QUEUED;
1563
1564         hdr = &conn->tmhdr;
1565         iscsi_prep_abort_task_pdu(ctask, hdr);
1566
1567         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1568                 rc = FAILED;
1569                 goto failed;
1570         }
1571
1572         switch (conn->tmf_state) {
1573         case TMF_SUCCESS:
1574                 spin_unlock_bh(&session->lock);
1575                 iscsi_suspend_tx(conn);
1576                 /*
1577                  * clean up task if aborted. grab the recv lock as a writer
1578                  */
1579                 write_lock_bh(conn->recv_lock);
1580                 spin_lock(&session->lock);
1581                 fail_command(conn, ctask, DID_ABORT << 16);
1582                 conn->tmf_state = TMF_INITIAL;
1583                 spin_unlock(&session->lock);
1584                 write_unlock_bh(conn->recv_lock);
1585                 iscsi_start_tx(conn);
1586                 goto success_unlocked;
1587         case TMF_TIMEDOUT:
1588                 spin_unlock_bh(&session->lock);
1589                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1590                 goto failed_unlocked;
1591         case TMF_NOT_FOUND:
1592                 if (!sc->SCp.ptr) {
1593                         conn->tmf_state = TMF_INITIAL;
1594                         /* ctask completed before tmf abort response */
1595                         debug_scsi("sc completed while abort in progress\n");
1596                         goto success;
1597                 }
1598                 /* fall through */
1599         default:
1600                 conn->tmf_state = TMF_INITIAL;
1601                 goto failed;
1602         }
1603
1604 success:
1605         spin_unlock_bh(&session->lock);
1606 success_unlocked:
1607         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1608         mutex_unlock(&session->eh_mutex);
1609         return SUCCESS;
1610
1611 failed:
1612         spin_unlock_bh(&session->lock);
1613 failed_unlocked:
1614         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1615                     ctask ? ctask->itt : 0);
1616         mutex_unlock(&session->eh_mutex);
1617         return FAILED;
1618 }
1619 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1620
1621 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1622 {
1623         memset(hdr, 0, sizeof(*hdr));
1624         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1625         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1626         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1627         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1628         hdr->rtt = RESERVED_ITT;
1629 }
1630
1631 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1632 {
1633         struct Scsi_Host *host = sc->device->host;
1634         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1635         struct iscsi_conn *conn;
1636         struct iscsi_tm *hdr;
1637         int rc = FAILED;
1638
1639         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1640
1641         mutex_lock(&session->eh_mutex);
1642         spin_lock_bh(&session->lock);
1643         /*
1644          * Just check if we are not logged in. We cannot check for
1645          * the phase because the reset could come from a ioctl.
1646          */
1647         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1648                 goto unlock;
1649         conn = session->leadconn;
1650
1651         /* only have one tmf outstanding at a time */
1652         if (conn->tmf_state != TMF_INITIAL)
1653                 goto unlock;
1654         conn->tmf_state = TMF_QUEUED;
1655
1656         hdr = &conn->tmhdr;
1657         iscsi_prep_lun_reset_pdu(sc, hdr);
1658
1659         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1660                                     session->lu_reset_timeout)) {
1661                 rc = FAILED;
1662                 goto unlock;
1663         }
1664
1665         switch (conn->tmf_state) {
1666         case TMF_SUCCESS:
1667                 break;
1668         case TMF_TIMEDOUT:
1669                 spin_unlock_bh(&session->lock);
1670                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1671                 goto done;
1672         default:
1673                 conn->tmf_state = TMF_INITIAL;
1674                 goto unlock;
1675         }
1676
1677         rc = SUCCESS;
1678         spin_unlock_bh(&session->lock);
1679
1680         iscsi_suspend_tx(conn);
1681         /* need to grab the recv lock then session lock */
1682         write_lock_bh(conn->recv_lock);
1683         spin_lock(&session->lock);
1684         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1685         conn->tmf_state = TMF_INITIAL;
1686         spin_unlock(&session->lock);
1687         write_unlock_bh(conn->recv_lock);
1688
1689         iscsi_start_tx(conn);
1690         goto done;
1691
1692 unlock:
1693         spin_unlock_bh(&session->lock);
1694 done:
1695         debug_scsi("iscsi_eh_device_reset %s\n",
1696                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1697         mutex_unlock(&session->eh_mutex);
1698         return rc;
1699 }
1700 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1701
1702 /*
1703  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1704  * should be accessed via kfifo_{get,put} on q->queue.
1705  * Optionally, the caller can obtain the array of object pointers
1706  * by passing in a non-NULL @items pointer
1707  */
1708 int
1709 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1710 {
1711         int i, num_arrays = 1;
1712
1713         memset(q, 0, sizeof(*q));
1714
1715         q->max = max;
1716
1717         /* If the user passed an items pointer, he wants a copy of
1718          * the array. */
1719         if (items)
1720                 num_arrays++;
1721         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1722         if (q->pool == NULL)
1723                 goto enomem;
1724
1725         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1726                               GFP_KERNEL, NULL);
1727         if (q->queue == ERR_PTR(-ENOMEM))
1728                 goto enomem;
1729
1730         for (i = 0; i < max; i++) {
1731                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1732                 if (q->pool[i] == NULL) {
1733                         q->max = i;
1734                         goto enomem;
1735                 }
1736                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1737         }
1738
1739         if (items) {
1740                 *items = q->pool + max;
1741                 memcpy(*items, q->pool, max * sizeof(void *));
1742         }
1743
1744         return 0;
1745
1746 enomem:
1747         iscsi_pool_free(q);
1748         return -ENOMEM;
1749 }
1750 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1751
1752 void iscsi_pool_free(struct iscsi_pool *q)
1753 {
1754         int i;
1755
1756         for (i = 0; i < q->max; i++)
1757                 kfree(q->pool[i]);
1758         if (q->pool)
1759                 kfree(q->pool);
1760 }
1761 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1762
1763 /*
1764  * iSCSI Session's hostdata organization:
1765  *
1766  *    *------------------* <== hostdata_session(host->hostdata)
1767  *    | ptr to class sess|
1768  *    |------------------| <== iscsi_hostdata(host->hostdata)
1769  *    | iscsi_session    |
1770  *    *------------------*
1771  */
1772
1773 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1774                                  _sz % sizeof(unsigned long))
1775
1776 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1777
1778 /**
1779  * iscsi_session_setup - create iscsi cls session and host and session
1780  * @scsit: scsi transport template
1781  * @iscsit: iscsi transport template
1782  * @cmds_max: scsi host can queue
1783  * @qdepth: scsi host cmds per lun
1784  * @cmd_task_size: LLD ctask private data size
1785  * @mgmt_task_size: LLD mtask private data size
1786  * @initial_cmdsn: initial CmdSN
1787  * @hostno: host no allocated
1788  *
1789  * This can be used by software iscsi_transports that allocate
1790  * a session per scsi host.
1791  **/
1792 struct iscsi_cls_session *
1793 iscsi_session_setup(struct iscsi_transport *iscsit,
1794                     struct scsi_transport_template *scsit,
1795                     uint16_t cmds_max, uint16_t qdepth,
1796                     int cmd_task_size, int mgmt_task_size,
1797                     uint32_t initial_cmdsn, uint32_t *hostno)
1798 {
1799         struct Scsi_Host *shost;
1800         struct iscsi_session *session;
1801         struct iscsi_cls_session *cls_session;
1802         int cmd_i;
1803
1804         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1805                 if (qdepth != 0)
1806                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1807                               "Queue depth must be between 1 and %d.\n",
1808                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1809                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1810         }
1811
1812         if (!is_power_of_2(cmds_max) || cmds_max >= ISCSI_MGMT_ITT_OFFSET ||
1813             cmds_max < 2) {
1814                 if (cmds_max != 0)
1815                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1816                                "can_queue must be a power of 2 and between "
1817                                "2 and %d - setting to %d.\n", cmds_max,
1818                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1819                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1820         }
1821
1822         shost = scsi_host_alloc(iscsit->host_template,
1823                                 hostdata_privsize(sizeof(*session)));
1824         if (!shost)
1825                 return NULL;
1826
1827         /* the iscsi layer takes one task for reserve */
1828         shost->can_queue = cmds_max - 1;
1829         shost->cmd_per_lun = qdepth;
1830         shost->max_id = 1;
1831         shost->max_channel = 0;
1832         shost->max_lun = iscsit->max_lun;
1833         shost->max_cmd_len = iscsit->max_cmd_len;
1834         shost->transportt = scsit;
1835         shost->transportt->create_work_queue = 1;
1836         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1837         *hostno = shost->host_no;
1838
1839         session = iscsi_hostdata(shost->hostdata);
1840         memset(session, 0, sizeof(struct iscsi_session));
1841         session->host = shost;
1842         session->state = ISCSI_STATE_FREE;
1843         session->fast_abort = 1;
1844         session->lu_reset_timeout = 15;
1845         session->abort_timeout = 10;
1846         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1847         session->cmds_max = cmds_max;
1848         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1849         session->exp_cmdsn = initial_cmdsn + 1;
1850         session->max_cmdsn = initial_cmdsn + 1;
1851         session->max_r2t = 1;
1852         session->tt = iscsit;
1853         mutex_init(&session->eh_mutex);
1854
1855         /* initialize SCSI PDU commands pool */
1856         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1857                             (void***)&session->cmds,
1858                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1859                 goto cmdpool_alloc_fail;
1860
1861         /* pre-format cmds pool with ITT */
1862         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1863                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1864
1865                 if (cmd_task_size)
1866                         ctask->dd_data = &ctask[1];
1867                 ctask->itt = cmd_i;
1868                 INIT_LIST_HEAD(&ctask->running);
1869         }
1870
1871         spin_lock_init(&session->lock);
1872
1873         /* initialize immediate command pool */
1874         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1875                            (void***)&session->mgmt_cmds,
1876                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1877                 goto mgmtpool_alloc_fail;
1878
1879
1880         /* pre-format immediate cmds pool with ITT */
1881         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1882                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1883
1884                 if (mgmt_task_size)
1885                         mtask->dd_data = &mtask[1];
1886                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1887                 INIT_LIST_HEAD(&mtask->running);
1888         }
1889
1890         if (scsi_add_host(shost, NULL))
1891                 goto add_host_fail;
1892
1893         if (!try_module_get(iscsit->owner))
1894                 goto cls_session_fail;
1895
1896         cls_session = iscsi_create_session(shost, iscsit, 0);
1897         if (!cls_session)
1898                 goto module_put;
1899         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1900
1901         return cls_session;
1902
1903 module_put:
1904         module_put(iscsit->owner);
1905 cls_session_fail:
1906         scsi_remove_host(shost);
1907 add_host_fail:
1908         iscsi_pool_free(&session->mgmtpool);
1909 mgmtpool_alloc_fail:
1910         iscsi_pool_free(&session->cmdpool);
1911 cmdpool_alloc_fail:
1912         scsi_host_put(shost);
1913         return NULL;
1914 }
1915 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1916
1917 /**
1918  * iscsi_session_teardown - destroy session, host, and cls_session
1919  * shost: scsi host
1920  *
1921  * This can be used by software iscsi_transports that allocate
1922  * a session per scsi host.
1923  **/
1924 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1925 {
1926         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1927         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1928         struct module *owner = cls_session->transport->owner;
1929
1930         iscsi_remove_session(cls_session);
1931         scsi_remove_host(shost);
1932
1933         iscsi_pool_free(&session->mgmtpool);
1934         iscsi_pool_free(&session->cmdpool);
1935
1936         kfree(session->password);
1937         kfree(session->password_in);
1938         kfree(session->username);
1939         kfree(session->username_in);
1940         kfree(session->targetname);
1941         kfree(session->netdev);
1942         kfree(session->hwaddress);
1943         kfree(session->initiatorname);
1944
1945         iscsi_free_session(cls_session);
1946         scsi_host_put(shost);
1947         module_put(owner);
1948 }
1949 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1950
1951 /**
1952  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1953  * @cls_session: iscsi_cls_session
1954  * @conn_idx: cid
1955  **/
1956 struct iscsi_cls_conn *
1957 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1958 {
1959         struct iscsi_session *session = class_to_transport_session(cls_session);
1960         struct iscsi_conn *conn;
1961         struct iscsi_cls_conn *cls_conn;
1962         char *data;
1963
1964         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1965         if (!cls_conn)
1966                 return NULL;
1967         conn = cls_conn->dd_data;
1968         memset(conn, 0, sizeof(*conn));
1969
1970         conn->session = session;
1971         conn->cls_conn = cls_conn;
1972         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1973         conn->id = conn_idx;
1974         conn->exp_statsn = 0;
1975         conn->tmf_state = TMF_INITIAL;
1976
1977         init_timer(&conn->transport_timer);
1978         conn->transport_timer.data = (unsigned long)conn;
1979         conn->transport_timer.function = iscsi_check_transport_timeouts;
1980
1981         INIT_LIST_HEAD(&conn->run_list);
1982         INIT_LIST_HEAD(&conn->mgmt_run_list);
1983         INIT_LIST_HEAD(&conn->mgmtqueue);
1984         INIT_LIST_HEAD(&conn->xmitqueue);
1985         INIT_LIST_HEAD(&conn->requeue);
1986         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1987
1988         /* allocate login_mtask used for the login/text sequences */
1989         spin_lock_bh(&session->lock);
1990         if (!__kfifo_get(session->mgmtpool.queue,
1991                          (void*)&conn->login_mtask,
1992                          sizeof(void*))) {
1993                 spin_unlock_bh(&session->lock);
1994                 goto login_mtask_alloc_fail;
1995         }
1996         spin_unlock_bh(&session->lock);
1997
1998         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1999         if (!data)
2000                 goto login_mtask_data_alloc_fail;
2001         conn->login_mtask->data = conn->data = data;
2002
2003         init_timer(&conn->tmf_timer);
2004         init_waitqueue_head(&conn->ehwait);
2005
2006         return cls_conn;
2007
2008 login_mtask_data_alloc_fail:
2009         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2010                     sizeof(void*));
2011 login_mtask_alloc_fail:
2012         iscsi_destroy_conn(cls_conn);
2013         return NULL;
2014 }
2015 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2016
2017 /**
2018  * iscsi_conn_teardown - teardown iscsi connection
2019  * cls_conn: iscsi class connection
2020  *
2021  * TODO: we may need to make this into a two step process
2022  * like scsi-mls remove + put host
2023  */
2024 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2025 {
2026         struct iscsi_conn *conn = cls_conn->dd_data;
2027         struct iscsi_session *session = conn->session;
2028         unsigned long flags;
2029
2030         del_timer_sync(&conn->transport_timer);
2031
2032         spin_lock_bh(&session->lock);
2033         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2034         if (session->leadconn == conn) {
2035                 /*
2036                  * leading connection? then give up on recovery.
2037                  */
2038                 session->state = ISCSI_STATE_TERMINATE;
2039                 wake_up(&conn->ehwait);
2040         }
2041         spin_unlock_bh(&session->lock);
2042
2043         /*
2044          * Block until all in-progress commands for this connection
2045          * time out or fail.
2046          */
2047         for (;;) {
2048                 spin_lock_irqsave(session->host->host_lock, flags);
2049                 if (!session->host->host_busy) { /* OK for ERL == 0 */
2050                         spin_unlock_irqrestore(session->host->host_lock, flags);
2051                         break;
2052                 }
2053                 spin_unlock_irqrestore(session->host->host_lock, flags);
2054                 msleep_interruptible(500);
2055                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2056                                   "host_busy %d host_failed %d\n",
2057                                   session->host->host_busy,
2058                                   session->host->host_failed);
2059                 /*
2060                  * force eh_abort() to unblock
2061                  */
2062                 wake_up(&conn->ehwait);
2063         }
2064
2065         /* flush queued up work because we free the connection below */
2066         iscsi_suspend_tx(conn);
2067
2068         spin_lock_bh(&session->lock);
2069         kfree(conn->data);
2070         kfree(conn->persistent_address);
2071         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2072                     sizeof(void*));
2073         if (session->leadconn == conn)
2074                 session->leadconn = NULL;
2075         spin_unlock_bh(&session->lock);
2076
2077         iscsi_destroy_conn(cls_conn);
2078 }
2079 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2080
2081 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2082 {
2083         struct iscsi_conn *conn = cls_conn->dd_data;
2084         struct iscsi_session *session = conn->session;
2085
2086         if (!session) {
2087                 iscsi_conn_printk(KERN_ERR, conn,
2088                                   "can't start unbound connection\n");
2089                 return -EPERM;
2090         }
2091
2092         if ((session->imm_data_en || !session->initial_r2t_en) &&
2093              session->first_burst > session->max_burst) {
2094                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2095                                   "first_burst %d max_burst %d\n",
2096                                   session->first_burst, session->max_burst);
2097                 return -EINVAL;
2098         }
2099
2100         if (conn->ping_timeout && !conn->recv_timeout) {
2101                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2102                                   "zero. Using 5 seconds\n.");
2103                 conn->recv_timeout = 5;
2104         }
2105
2106         if (conn->recv_timeout && !conn->ping_timeout) {
2107                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2108                                   "zero. Using 5 seconds.\n");
2109                 conn->ping_timeout = 5;
2110         }
2111
2112         spin_lock_bh(&session->lock);
2113         conn->c_stage = ISCSI_CONN_STARTED;
2114         session->state = ISCSI_STATE_LOGGED_IN;
2115         session->queued_cmdsn = session->cmdsn;
2116
2117         conn->last_recv = jiffies;
2118         conn->last_ping = jiffies;
2119         if (conn->recv_timeout && conn->ping_timeout)
2120                 mod_timer(&conn->transport_timer,
2121                           jiffies + (conn->recv_timeout * HZ));
2122
2123         switch(conn->stop_stage) {
2124         case STOP_CONN_RECOVER:
2125                 /*
2126                  * unblock eh_abort() if it is blocked. re-try all
2127                  * commands after successful recovery
2128                  */
2129                 conn->stop_stage = 0;
2130                 conn->tmf_state = TMF_INITIAL;
2131                 session->age++;
2132                 if (session->age == 16)
2133                         session->age = 0;
2134                 break;
2135         case STOP_CONN_TERM:
2136                 conn->stop_stage = 0;
2137                 break;
2138         default:
2139                 break;
2140         }
2141         spin_unlock_bh(&session->lock);
2142
2143         iscsi_unblock_session(session_to_cls(session));
2144         wake_up(&conn->ehwait);
2145         return 0;
2146 }
2147 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2148
2149 static void
2150 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2151 {
2152         struct iscsi_mgmt_task *mtask, *tmp;
2153
2154         /* handle pending */
2155         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2156                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2157                 iscsi_free_mgmt_task(conn, mtask);
2158         }
2159
2160         /* handle running */
2161         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2162                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2163                 iscsi_free_mgmt_task(conn, mtask);
2164         }
2165
2166         conn->mtask = NULL;
2167 }
2168
2169 static void iscsi_start_session_recovery(struct iscsi_session *session,
2170                                          struct iscsi_conn *conn, int flag)
2171 {
2172         int old_stop_stage;
2173
2174         del_timer_sync(&conn->transport_timer);
2175
2176         mutex_lock(&session->eh_mutex);
2177         spin_lock_bh(&session->lock);
2178         if (conn->stop_stage == STOP_CONN_TERM) {
2179                 spin_unlock_bh(&session->lock);
2180                 mutex_unlock(&session->eh_mutex);
2181                 return;
2182         }
2183
2184         /*
2185          * The LLD either freed/unset the lock on us, or userspace called
2186          * stop but did not create a proper connection (connection was never
2187          * bound or it was unbound then stop was called).
2188          */
2189         if (!conn->recv_lock) {
2190                 spin_unlock_bh(&session->lock);
2191                 mutex_unlock(&session->eh_mutex);
2192                 return;
2193         }
2194
2195         /*
2196          * When this is called for the in_login state, we only want to clean
2197          * up the login task and connection. We do not need to block and set
2198          * the recovery state again
2199          */
2200         if (flag == STOP_CONN_TERM)
2201                 session->state = ISCSI_STATE_TERMINATE;
2202         else if (conn->stop_stage != STOP_CONN_RECOVER)
2203                 session->state = ISCSI_STATE_IN_RECOVERY;
2204
2205         old_stop_stage = conn->stop_stage;
2206         conn->stop_stage = flag;
2207         conn->c_stage = ISCSI_CONN_STOPPED;
2208         spin_unlock_bh(&session->lock);
2209
2210         iscsi_suspend_tx(conn);
2211
2212         write_lock_bh(conn->recv_lock);
2213         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2214         write_unlock_bh(conn->recv_lock);
2215
2216         /*
2217          * for connection level recovery we should not calculate
2218          * header digest. conn->hdr_size used for optimization
2219          * in hdr_extract() and will be re-negotiated at
2220          * set_param() time.
2221          */
2222         if (flag == STOP_CONN_RECOVER) {
2223                 conn->hdrdgst_en = 0;
2224                 conn->datadgst_en = 0;
2225                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2226                     old_stop_stage != STOP_CONN_RECOVER) {
2227                         debug_scsi("blocking session\n");
2228                         iscsi_block_session(session_to_cls(session));
2229                 }
2230         }
2231
2232         /*
2233          * flush queues.
2234          */
2235         spin_lock_bh(&session->lock);
2236         fail_all_commands(conn, -1,
2237                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2238         flush_control_queues(session, conn);
2239         spin_unlock_bh(&session->lock);
2240         mutex_unlock(&session->eh_mutex);
2241 }
2242
2243 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2244 {
2245         struct iscsi_conn *conn = cls_conn->dd_data;
2246         struct iscsi_session *session = conn->session;
2247
2248         switch (flag) {
2249         case STOP_CONN_RECOVER:
2250         case STOP_CONN_TERM:
2251                 iscsi_start_session_recovery(session, conn, flag);
2252                 break;
2253         default:
2254                 iscsi_conn_printk(KERN_ERR, conn,
2255                                   "invalid stop flag %d\n", flag);
2256         }
2257 }
2258 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2259
2260 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2261                     struct iscsi_cls_conn *cls_conn, int is_leading)
2262 {
2263         struct iscsi_session *session = class_to_transport_session(cls_session);
2264         struct iscsi_conn *conn = cls_conn->dd_data;
2265
2266         spin_lock_bh(&session->lock);
2267         if (is_leading)
2268                 session->leadconn = conn;
2269         spin_unlock_bh(&session->lock);
2270
2271         /*
2272          * Unblock xmitworker(), Login Phase will pass through.
2273          */
2274         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2275         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2276         return 0;
2277 }
2278 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2279
2280
2281 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2282                     enum iscsi_param param, char *buf, int buflen)
2283 {
2284         struct iscsi_conn *conn = cls_conn->dd_data;
2285         struct iscsi_session *session = conn->session;
2286         uint32_t value;
2287
2288         switch(param) {
2289         case ISCSI_PARAM_FAST_ABORT:
2290                 sscanf(buf, "%d", &session->fast_abort);
2291                 break;
2292         case ISCSI_PARAM_ABORT_TMO:
2293                 sscanf(buf, "%d", &session->abort_timeout);
2294                 break;
2295         case ISCSI_PARAM_LU_RESET_TMO:
2296                 sscanf(buf, "%d", &session->lu_reset_timeout);
2297                 break;
2298         case ISCSI_PARAM_PING_TMO:
2299                 sscanf(buf, "%d", &conn->ping_timeout);
2300                 break;
2301         case ISCSI_PARAM_RECV_TMO:
2302                 sscanf(buf, "%d", &conn->recv_timeout);
2303                 break;
2304         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2305                 sscanf(buf, "%d", &conn->max_recv_dlength);
2306                 break;
2307         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2308                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2309                 break;
2310         case ISCSI_PARAM_HDRDGST_EN:
2311                 sscanf(buf, "%d", &conn->hdrdgst_en);
2312                 break;
2313         case ISCSI_PARAM_DATADGST_EN:
2314                 sscanf(buf, "%d", &conn->datadgst_en);
2315                 break;
2316         case ISCSI_PARAM_INITIAL_R2T_EN:
2317                 sscanf(buf, "%d", &session->initial_r2t_en);
2318                 break;
2319         case ISCSI_PARAM_MAX_R2T:
2320                 sscanf(buf, "%d", &session->max_r2t);
2321                 break;
2322         case ISCSI_PARAM_IMM_DATA_EN:
2323                 sscanf(buf, "%d", &session->imm_data_en);
2324                 break;
2325         case ISCSI_PARAM_FIRST_BURST:
2326                 sscanf(buf, "%d", &session->first_burst);
2327                 break;
2328         case ISCSI_PARAM_MAX_BURST:
2329                 sscanf(buf, "%d", &session->max_burst);
2330                 break;
2331         case ISCSI_PARAM_PDU_INORDER_EN:
2332                 sscanf(buf, "%d", &session->pdu_inorder_en);
2333                 break;
2334         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2335                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2336                 break;
2337         case ISCSI_PARAM_ERL:
2338                 sscanf(buf, "%d", &session->erl);
2339                 break;
2340         case ISCSI_PARAM_IFMARKER_EN:
2341                 sscanf(buf, "%d", &value);
2342                 BUG_ON(value);
2343                 break;
2344         case ISCSI_PARAM_OFMARKER_EN:
2345                 sscanf(buf, "%d", &value);
2346                 BUG_ON(value);
2347                 break;
2348         case ISCSI_PARAM_EXP_STATSN:
2349                 sscanf(buf, "%u", &conn->exp_statsn);
2350                 break;
2351         case ISCSI_PARAM_USERNAME:
2352                 kfree(session->username);
2353                 session->username = kstrdup(buf, GFP_KERNEL);
2354                 if (!session->username)
2355                         return -ENOMEM;
2356                 break;
2357         case ISCSI_PARAM_USERNAME_IN:
2358                 kfree(session->username_in);
2359                 session->username_in = kstrdup(buf, GFP_KERNEL);
2360                 if (!session->username_in)
2361                         return -ENOMEM;
2362                 break;
2363         case ISCSI_PARAM_PASSWORD:
2364                 kfree(session->password);
2365                 session->password = kstrdup(buf, GFP_KERNEL);
2366                 if (!session->password)
2367                         return -ENOMEM;
2368                 break;
2369         case ISCSI_PARAM_PASSWORD_IN:
2370                 kfree(session->password_in);
2371                 session->password_in = kstrdup(buf, GFP_KERNEL);
2372                 if (!session->password_in)
2373                         return -ENOMEM;
2374                 break;
2375         case ISCSI_PARAM_TARGET_NAME:
2376                 /* this should not change between logins */
2377                 if (session->targetname)
2378                         break;
2379
2380                 session->targetname = kstrdup(buf, GFP_KERNEL);
2381                 if (!session->targetname)
2382                         return -ENOMEM;
2383                 break;
2384         case ISCSI_PARAM_TPGT:
2385                 sscanf(buf, "%d", &session->tpgt);
2386                 break;
2387         case ISCSI_PARAM_PERSISTENT_PORT:
2388                 sscanf(buf, "%d", &conn->persistent_port);
2389                 break;
2390         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2391                 /*
2392                  * this is the address returned in discovery so it should
2393                  * not change between logins.
2394                  */
2395                 if (conn->persistent_address)
2396                         break;
2397
2398                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2399                 if (!conn->persistent_address)
2400                         return -ENOMEM;
2401                 break;
2402         default:
2403                 return -ENOSYS;
2404         }
2405
2406         return 0;
2407 }
2408 EXPORT_SYMBOL_GPL(iscsi_set_param);
2409
2410 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2411                             enum iscsi_param param, char *buf)
2412 {
2413         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2414         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2415         int len;
2416
2417         switch(param) {
2418         case ISCSI_PARAM_FAST_ABORT:
2419                 len = sprintf(buf, "%d\n", session->fast_abort);
2420                 break;
2421         case ISCSI_PARAM_ABORT_TMO:
2422                 len = sprintf(buf, "%d\n", session->abort_timeout);
2423                 break;
2424         case ISCSI_PARAM_LU_RESET_TMO:
2425                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2426                 break;
2427         case ISCSI_PARAM_INITIAL_R2T_EN:
2428                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2429                 break;
2430         case ISCSI_PARAM_MAX_R2T:
2431                 len = sprintf(buf, "%hu\n", session->max_r2t);
2432                 break;
2433         case ISCSI_PARAM_IMM_DATA_EN:
2434                 len = sprintf(buf, "%d\n", session->imm_data_en);
2435                 break;
2436         case ISCSI_PARAM_FIRST_BURST:
2437                 len = sprintf(buf, "%u\n", session->first_burst);
2438                 break;
2439         case ISCSI_PARAM_MAX_BURST:
2440                 len = sprintf(buf, "%u\n", session->max_burst);
2441                 break;
2442         case ISCSI_PARAM_PDU_INORDER_EN:
2443                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2444                 break;
2445         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2446                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2447                 break;
2448         case ISCSI_PARAM_ERL:
2449                 len = sprintf(buf, "%d\n", session->erl);
2450                 break;
2451         case ISCSI_PARAM_TARGET_NAME:
2452                 len = sprintf(buf, "%s\n", session->targetname);
2453                 break;
2454         case ISCSI_PARAM_TPGT:
2455                 len = sprintf(buf, "%d\n", session->tpgt);
2456                 break;
2457         case ISCSI_PARAM_USERNAME:
2458                 len = sprintf(buf, "%s\n", session->username);
2459                 break;
2460         case ISCSI_PARAM_USERNAME_IN:
2461                 len = sprintf(buf, "%s\n", session->username_in);
2462                 break;
2463         case ISCSI_PARAM_PASSWORD:
2464                 len = sprintf(buf, "%s\n", session->password);
2465                 break;
2466         case ISCSI_PARAM_PASSWORD_IN:
2467                 len = sprintf(buf, "%s\n", session->password_in);
2468                 break;
2469         default:
2470                 return -ENOSYS;
2471         }
2472
2473         return len;
2474 }
2475 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2476
2477 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2478                          enum iscsi_param param, char *buf)
2479 {
2480         struct iscsi_conn *conn = cls_conn->dd_data;
2481         int len;
2482
2483         switch(param) {
2484         case ISCSI_PARAM_PING_TMO:
2485                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2486                 break;
2487         case ISCSI_PARAM_RECV_TMO:
2488                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2489                 break;
2490         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2491                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2492                 break;
2493         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2494                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2495                 break;
2496         case ISCSI_PARAM_HDRDGST_EN:
2497                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2498                 break;
2499         case ISCSI_PARAM_DATADGST_EN:
2500                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2501                 break;
2502         case ISCSI_PARAM_IFMARKER_EN:
2503                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2504                 break;
2505         case ISCSI_PARAM_OFMARKER_EN:
2506                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2507                 break;
2508         case ISCSI_PARAM_EXP_STATSN:
2509                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2510                 break;
2511         case ISCSI_PARAM_PERSISTENT_PORT:
2512                 len = sprintf(buf, "%d\n", conn->persistent_port);
2513                 break;
2514         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2515                 len = sprintf(buf, "%s\n", conn->persistent_address);
2516                 break;
2517         default:
2518                 return -ENOSYS;
2519         }
2520
2521         return len;
2522 }
2523 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2524
2525 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2526                          char *buf)
2527 {
2528         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2529         int len;
2530
2531         switch (param) {
2532         case ISCSI_HOST_PARAM_NETDEV_NAME:
2533                 if (!session->netdev)
2534                         len = sprintf(buf, "%s\n", "default");
2535                 else
2536                         len = sprintf(buf, "%s\n", session->netdev);
2537                 break;
2538         case ISCSI_HOST_PARAM_HWADDRESS:
2539                 if (!session->hwaddress)
2540                         len = sprintf(buf, "%s\n", "default");
2541                 else
2542                         len = sprintf(buf, "%s\n", session->hwaddress);
2543                 break;
2544         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2545                 if (!session->initiatorname)
2546                         len = sprintf(buf, "%s\n", "unknown");
2547                 else
2548                         len = sprintf(buf, "%s\n", session->initiatorname);
2549                 break;
2550
2551         default:
2552                 return -ENOSYS;
2553         }
2554
2555         return len;
2556 }
2557 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2558
2559 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2560                          char *buf, int buflen)
2561 {
2562         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2563
2564         switch (param) {
2565         case ISCSI_HOST_PARAM_NETDEV_NAME:
2566                 if (!session->netdev)
2567                         session->netdev = kstrdup(buf, GFP_KERNEL);
2568                 break;
2569         case ISCSI_HOST_PARAM_HWADDRESS:
2570                 if (!session->hwaddress)
2571                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2572                 break;
2573         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2574                 if (!session->initiatorname)
2575                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2576                 break;
2577         default:
2578                 return -ENOSYS;
2579         }
2580
2581         return 0;
2582 }
2583 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2584
2585 MODULE_AUTHOR("Mike Christie");
2586 MODULE_DESCRIPTION("iSCSI library functions");
2587 MODULE_LICENSE("GPL");