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