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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * iSCSI lib functions
  3  *
  4  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
  5  * Copyright (C) 2004 - 2006 Mike Christie
  6  * Copyright (C) 2004 - 2005 Dmitry Yusupov
  7  * Copyright (C) 2004 - 2005 Alex Aizman
  8  * maintained by open-iscsi@googlegroups.com
  9  *
 10  * This program is free software; you can redistribute it and/or modify
 11  * it under the terms of the GNU General Public License as published by
 12  * the Free Software Foundation; either version 2 of the License, or
 13  * (at your option) any later version.
 14  *
 15  * This program is distributed in the hope that it will be useful,
 16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 18  * GNU General Public License for more details.
 19  *
 20  * You should have received a copy of the GNU General Public License
 21  * along with this program; if not, write to the Free Software
 22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 23  */
 24 #include <linux/types.h>
 25 #include <linux/kfifo.h>
 26 #include <linux/delay.h>
 27 #include <linux/log2.h>
 28 #include <asm/unaligned.h>
 29 #include <net/tcp.h>
 30 #include <scsi/scsi_cmnd.h>
 31 #include <scsi/scsi_device.h>
 32 #include <scsi/scsi_eh.h>
 33 #include <scsi/scsi_tcq.h>
 34 #include <scsi/scsi_host.h>
 35 #include <scsi/scsi.h>
 36 #include <scsi/iscsi_proto.h>
 37 #include <scsi/scsi_transport.h>
 38 #include <scsi/scsi_transport_iscsi.h>
 39 #include <scsi/libiscsi.h>
 40 
 41 struct iscsi_session *
 42 class_to_transport_session(struct iscsi_cls_session *cls_session)
 43 {
 44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 45         return iscsi_hostdata(shost->hostdata);
 46 }
 47 EXPORT_SYMBOL_GPL(class_to_transport_session);
 48 
 49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
 50 #define SNA32_CHECK 2147483648UL
 51 
 52 static int iscsi_sna_lt(u32 n1, u32 n2)
 53 {
 54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
 55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
 56 }
 57 
 58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
 59 static int iscsi_sna_lte(u32 n1, u32 n2)
 60 {
 61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
 62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
 63 }
 64 
 65 void
 66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
 67 {
 68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
 69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
 70 
 71         /*
 72          * standard specifies this check for when to update expected and
 73          * max sequence numbers
 74          */
 75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
 76                 return;
 77 
 78         if (exp_cmdsn != session->exp_cmdsn &&
 79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
 80                 session->exp_cmdsn = exp_cmdsn;
 81 
 82         if (max_cmdsn != session->max_cmdsn &&
 83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
 84                 session->max_cmdsn = max_cmdsn;
 85                 /*
 86                  * if the window closed with IO queued, then kick the
 87                  * xmit thread
 88                  */
 89                 if (!list_empty(&session->leadconn->xmitqueue) ||
 90                     !list_empty(&session->leadconn->mgmtqueue))
 91                         scsi_queue_work(session->host,
 92                                         &session->leadconn->xmitwork);
 93         }
 94 }
 95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
 96 
 97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
 98                                    struct iscsi_data *hdr)
 99 {
100         struct iscsi_conn *conn = ctask->conn;
101 
102         memset(hdr, 0, sizeof(struct iscsi_data));
103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
105         ctask->unsol_datasn++;
106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
108 
109         hdr->itt = ctask->hdr->itt;
110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
112 
113         if (ctask->unsol_count > conn->max_xmit_dlength) {
114                 hton24(hdr->dlength, conn->max_xmit_dlength);
115                 ctask->data_count = conn->max_xmit_dlength;
116                 ctask->unsol_offset += ctask->data_count;
117                 hdr->flags = 0;
118         } else {
119                 hton24(hdr->dlength, ctask->unsol_count);
120                 ctask->data_count = ctask->unsol_count;
121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
122         }
123 }
124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
125 
126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
127 {
128         unsigned exp_len = ctask->hdr_len + len;
129 
130         if (exp_len > ctask->hdr_max) {
131                 WARN_ON(1);
132                 return -EINVAL;
133         }
134 
135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
136         ctask->hdr_len = exp_len;
137         return 0;
138 }
139 
140 /**
141  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
142  * @ctask: iscsi cmd task
143  *
144  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
145  * fields like dlength or final based on how much data it sends
146  */
147 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
148 {
149         struct iscsi_conn *conn = ctask->conn;
150         struct iscsi_session *session = conn->session;
151         struct iscsi_cmd *hdr = ctask->hdr;
152         struct scsi_cmnd *sc = ctask->sc;
153         unsigned hdrlength;
154         int rc;
155 
156         ctask->hdr_len = 0;
157         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
158         if (rc)
159                 return rc;
160         hdr->opcode = ISCSI_OP_SCSI_CMD;
161         hdr->flags = ISCSI_ATTR_SIMPLE;
162         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
163         hdr->itt = build_itt(ctask->itt, session->age);
164         hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
165         hdr->cmdsn = cpu_to_be32(session->cmdsn);
166         session->cmdsn++;
167         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
168         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
169         if (sc->cmd_len < MAX_COMMAND_SIZE)
170                 memset(&hdr->cdb[sc->cmd_len], 0,
171                         MAX_COMMAND_SIZE - sc->cmd_len);
172 
173         ctask->imm_count = 0;
174         if (sc->sc_data_direction == DMA_TO_DEVICE) {
175                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
176                 /*
177                  * Write counters:
178                  *
179                  *      imm_count       bytes to be sent right after
180                  *                      SCSI PDU Header
181                  *
182                  *      unsol_count     bytes(as Data-Out) to be sent
183                  *                      without R2T ack right after
184                  *                      immediate data
185                  *
186                  *      r2t_data_count  bytes to be sent via R2T ack's
187                  *
188                  *      pad_count       bytes to be sent as zero-padding
189                  */
190                 ctask->unsol_count = 0;
191                 ctask->unsol_offset = 0;
192                 ctask->unsol_datasn = 0;
193 
194                 if (session->imm_data_en) {
195                         if (scsi_bufflen(sc) >= session->first_burst)
196                                 ctask->imm_count = min(session->first_burst,
197                                                         conn->max_xmit_dlength);
198                         else
199                                 ctask->imm_count = min(scsi_bufflen(sc),
200                                                         conn->max_xmit_dlength);
201                         hton24(hdr->dlength, ctask->imm_count);
202                 } else
203                         zero_data(hdr->dlength);
204 
205                 if (!session->initial_r2t_en) {
206                         ctask->unsol_count = min((session->first_burst),
207                                 (scsi_bufflen(sc))) - ctask->imm_count;
208                         ctask->unsol_offset = ctask->imm_count;
209                 }
210 
211                 if (!ctask->unsol_count)
212                         /* No unsolicit Data-Out's */
213                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
214         } else {
215                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
216                 zero_data(hdr->dlength);
217 
218                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
219                         hdr->flags |= ISCSI_FLAG_CMD_READ;
220         }
221 
222         /* calculate size of additional header segments (AHSs) */
223         hdrlength = ctask->hdr_len - sizeof(*hdr);
224 
225         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
226         hdrlength /= ISCSI_PAD_LEN;
227 
228         WARN_ON(hdrlength >= 256);
229         hdr->hlength = hdrlength & 0xFF;
230 
231         if (conn->session->tt->init_cmd_task(conn->ctask))
232                 return EIO;
233 
234         conn->scsicmd_pdus_cnt++;
235         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
236                 "cmdsn %d win %d]\n",
237                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
238                 conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
239                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
240         return 0;
241 }
242 
243 /**
244  * iscsi_complete_command - return command back to scsi-ml
245  * @ctask: iscsi cmd task
246  *
247  * Must be called with session lock.
248  * This function returns the scsi command to scsi-ml and returns
249  * the cmd task to the pool of available cmd tasks.
250  */
251 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
252 {
253         struct iscsi_conn *conn = ctask->conn;
254         struct iscsi_session *session = conn->session;
255         struct scsi_cmnd *sc = ctask->sc;
256 
257         ctask->state = ISCSI_TASK_COMPLETED;
258         ctask->sc = NULL;
259         /* SCSI eh reuses commands to verify us */
260         sc->SCp.ptr = NULL;
261         if (conn->ctask == ctask)
262                 conn->ctask = NULL;
263         list_del_init(&ctask->running);
264         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
265         sc->scsi_done(sc);
266 }
267 
268 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
269 {
270         atomic_inc(&ctask->refcount);
271 }
272 
273 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
274 {
275         if (atomic_dec_and_test(&ctask->refcount))
276                 iscsi_complete_command(ctask);
277 }
278 
279 /*
280  * session lock must be held
281  */
282 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
283                          int err)
284 {
285         struct scsi_cmnd *sc;
286 
287         sc = ctask->sc;
288         if (!sc)
289                 return;
290 
291         if (ctask->state == ISCSI_TASK_PENDING)
292                 /*
293                  * cmd never made it to the xmit thread, so we should not count
294                  * the cmd in the sequencing
295                  */
296                 conn->session->queued_cmdsn--;
297         else
298                 conn->session->tt->cleanup_cmd_task(conn, ctask);
299 
300         sc->result = err;
301         scsi_set_resid(sc, scsi_bufflen(sc));
302         if (conn->ctask == ctask)
303                 conn->ctask = NULL;
304         /* release ref from queuecommand */
305         __iscsi_put_ctask(ctask);
306 }
307 
308 /**
309  * iscsi_free_mgmt_task - return mgmt task back to pool
310  * @conn: iscsi connection
311  * @mtask: mtask
312  *
313  * Must be called with session lock.
314  */
315 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
316                           struct iscsi_mgmt_task *mtask)
317 {
318         list_del_init(&mtask->running);
319         if (conn->login_mtask == mtask)
320                 return;
321 
322         if (conn->ping_mtask == mtask)
323                 conn->ping_mtask = NULL;
324         __kfifo_put(conn->session->mgmtpool.queue,
325                     (void*)&mtask, sizeof(void*));
326 }
327 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
328 
329 static struct iscsi_mgmt_task *
330 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
331                       char *data, uint32_t data_size)
332 {
333         struct iscsi_session *session = conn->session;
334         struct iscsi_mgmt_task *mtask;
335 
336         if (session->state == ISCSI_STATE_TERMINATE)
337                 return NULL;
338 
339         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
340             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
341                 /*
342                  * Login and Text are sent serially, in
343                  * request-followed-by-response sequence.
344                  * Same mtask can be used. Same ITT must be used.
345                  * Note that login_mtask is preallocated at conn_create().
346                  */
347                 mtask = conn->login_mtask;
348         else {
349                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
350                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
351 
352                 if (!__kfifo_get(session->mgmtpool.queue,
353                                  (void*)&mtask, sizeof(void*)))
354                         return NULL;
355         }
356 
357         if (data_size) {
358                 memcpy(mtask->data, data, data_size);
359                 mtask->data_count = data_size;
360         } else
361                 mtask->data_count = 0;
362 
363         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
364         INIT_LIST_HEAD(&mtask->running);
365         list_add_tail(&mtask->running, &conn->mgmtqueue);
366         return mtask;
367 }
368 
369 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
370                         char *data, uint32_t data_size)
371 {
372         struct iscsi_conn *conn = cls_conn->dd_data;
373         struct iscsi_session *session = conn->session;
374         int err = 0;
375 
376         spin_lock_bh(&session->lock);
377         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
378                 err = -EPERM;
379         spin_unlock_bh(&session->lock);
380         scsi_queue_work(session->host, &conn->xmitwork);
381         return err;
382 }
383 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
384 
385 /**
386  * iscsi_cmd_rsp - SCSI Command Response processing
387  * @conn: iscsi connection
388  * @hdr: iscsi header
389  * @ctask: scsi command task
390  * @data: cmd data buffer
391  * @datalen: len of buffer
392  *
393  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
394  * then completes the command and task.
395  **/
396 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
397                                struct iscsi_cmd_task *ctask, char *data,
398                                int datalen)
399 {
400         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
401         struct iscsi_session *session = conn->session;
402         struct scsi_cmnd *sc = ctask->sc;
403 
404         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
405         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
406 
407         sc->result = (DID_OK << 16) | rhdr->cmd_status;
408 
409         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
410                 sc->result = DID_ERROR << 16;
411                 goto out;
412         }
413 
414         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
415                 uint16_t senselen;
416 
417                 if (datalen < 2) {
418 invalid_datalen:
419                         iscsi_conn_printk(KERN_ERR,  conn,
420                                          "Got CHECK_CONDITION but invalid data "
421                                          "buffer size of %d\n", datalen);
422                         sc->result = DID_BAD_TARGET << 16;
423                         goto out;
424                 }
425 
426                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
427                 if (datalen < senselen)
428                         goto invalid_datalen;
429 
430                 memcpy(sc->sense_buffer, data + 2,
431                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
432                 debug_scsi("copied %d bytes of sense\n",
433                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
434         }
435 
436         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
437                            ISCSI_FLAG_CMD_OVERFLOW)) {
438                 int res_count = be32_to_cpu(rhdr->residual_count);
439 
440                 if (res_count > 0 &&
441                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
442                      res_count <= scsi_bufflen(sc)))
443                         scsi_set_resid(sc, res_count);
444                 else
445                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
446         } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
447                                   ISCSI_FLAG_CMD_BIDI_OVERFLOW))
448                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
449 
450 out:
451         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
452                    (long)sc, sc->result, ctask->itt);
453         conn->scsirsp_pdus_cnt++;
454 
455         __iscsi_put_ctask(ctask);
456 }
457 
458 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
459 {
460         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
461 
462         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
463         conn->tmfrsp_pdus_cnt++;
464 
465         if (conn->tmf_state != TMF_QUEUED)
466                 return;
467 
468         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
469                 conn->tmf_state = TMF_SUCCESS;
470         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
471                 conn->tmf_state = TMF_NOT_FOUND;
472         else
473                 conn->tmf_state = TMF_FAILED;
474         wake_up(&conn->ehwait);
475 }
476 
477 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
478 {
479         struct iscsi_nopout hdr;
480         struct iscsi_mgmt_task *mtask;
481 
482         if (!rhdr && conn->ping_mtask)
483                 return;
484 
485         memset(&hdr, 0, sizeof(struct iscsi_nopout));
486         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
487         hdr.flags = ISCSI_FLAG_CMD_FINAL;
488 
489         if (rhdr) {
490                 memcpy(hdr.lun, rhdr->lun, 8);
491                 hdr.ttt = rhdr->ttt;
492                 hdr.itt = RESERVED_ITT;
493         } else
494                 hdr.ttt = RESERVED_ITT;
495 
496         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
497         if (!mtask) {
498                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
499                 return;
500         }
501 
502         /* only track our nops */
503         if (!rhdr) {
504                 conn->ping_mtask = mtask;
505                 conn->last_ping = jiffies;
506         }
507         scsi_queue_work(conn->session->host, &conn->xmitwork);
508 }
509 
510 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
511                                char *data, int datalen)
512 {
513         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
514         struct iscsi_hdr rejected_pdu;
515         uint32_t itt;
516 
517         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
518 
519         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
520                 if (ntoh24(reject->dlength) > datalen)
521                         return ISCSI_ERR_PROTO;
522 
523                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
524                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
525                         itt = get_itt(rejected_pdu.itt);
526                         iscsi_conn_printk(KERN_ERR, conn,
527                                           "itt 0x%x had pdu (op 0x%x) rejected "
528                                           "due to DataDigest error.\n", itt,
529                                           rejected_pdu.opcode);
530                 }
531         }
532         return 0;
533 }
534 
535 /**
536  * __iscsi_complete_pdu - complete pdu
537  * @conn: iscsi conn
538  * @hdr: iscsi header
539  * @data: data buffer
540  * @datalen: len of data buffer
541  *
542  * Completes pdu processing by freeing any resources allocated at
543  * queuecommand or send generic. session lock must be held and verify
544  * itt must have been called.
545  */
546 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
547                                 char *data, int datalen)
548 {
549         struct iscsi_session *session = conn->session;
550         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
551         struct iscsi_cmd_task *ctask;
552         struct iscsi_mgmt_task *mtask;
553         uint32_t itt;
554 
555         conn->last_recv = jiffies;
556         if (hdr->itt != RESERVED_ITT)
557                 itt = get_itt(hdr->itt);
558         else
559                 itt = ~0U;
560 
561         if (itt < session->cmds_max) {
562                 ctask = session->cmds[itt];
563 
564                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
565                            opcode, conn->id, ctask->itt, datalen);
566 
567                 switch(opcode) {
568                 case ISCSI_OP_SCSI_CMD_RSP:
569                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
570                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
571                                            datalen);
572                         break;
573                 case ISCSI_OP_SCSI_DATA_IN:
574                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
575                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
576                                 conn->scsirsp_pdus_cnt++;
577                                 __iscsi_put_ctask(ctask);
578                         }
579                         break;
580                 case ISCSI_OP_R2T:
581                         /* LLD handles this for now */
582                         break;
583                 default:
584                         rc = ISCSI_ERR_BAD_OPCODE;
585                         break;
586                 }
587         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
588                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
589                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
590 
591                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
592                            opcode, conn->id, mtask->itt, datalen);
593 
594                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
595                 switch(opcode) {
596                 case ISCSI_OP_LOGOUT_RSP:
597                         if (datalen) {
598                                 rc = ISCSI_ERR_PROTO;
599                                 break;
600                         }
601                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
602                         /* fall through */
603                 case ISCSI_OP_LOGIN_RSP:
604                 case ISCSI_OP_TEXT_RSP:
605                         /*
606                          * login related PDU's exp_statsn is handled in
607                          * userspace
608                          */
609                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
610                                 rc = ISCSI_ERR_CONN_FAILED;
611                         iscsi_free_mgmt_task(conn, mtask);
612                         break;
613                 case ISCSI_OP_SCSI_TMFUNC_RSP:
614                         if (datalen) {
615                                 rc = ISCSI_ERR_PROTO;
616                                 break;
617                         }
618 
619                         iscsi_tmf_rsp(conn, hdr);
620                         iscsi_free_mgmt_task(conn, mtask);
621                         break;
622                 case ISCSI_OP_NOOP_IN:
623                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
624                             datalen) {
625                                 rc = ISCSI_ERR_PROTO;
626                                 break;
627                         }
628                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
629 
630                         if (conn->ping_mtask != mtask) {
631                                 /*
632                                  * If this is not in response to one of our
633                                  * nops then it must be from userspace.
634                                  */
635                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
636                                                    datalen))
637                                         rc = ISCSI_ERR_CONN_FAILED;
638                         } else
639                                 mod_timer(&conn->transport_timer,
640                                           jiffies + conn->recv_timeout);
641                         iscsi_free_mgmt_task(conn, mtask);
642                         break;
643                 default:
644                         rc = ISCSI_ERR_BAD_OPCODE;
645                         break;
646                 }
647         } else if (itt == ~0U) {
648                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
649 
650                 switch(opcode) {
651                 case ISCSI_OP_NOOP_IN:
652                         if (datalen) {
653                                 rc = ISCSI_ERR_PROTO;
654                                 break;
655                         }
656 
657                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
658                                 break;
659 
660                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
661                         break;
662                 case ISCSI_OP_REJECT:
663                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
664                         break;
665                 case ISCSI_OP_ASYNC_EVENT:
666                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
667                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
668                                 rc = ISCSI_ERR_CONN_FAILED;
669                         break;
670                 default:
671                         rc = ISCSI_ERR_BAD_OPCODE;
672                         break;
673                 }
674         } else
675                 rc = ISCSI_ERR_BAD_ITT;
676 
677         return rc;
678 }
679 
680 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
681                        char *data, int datalen)
682 {
683         int rc;
684 
685         spin_lock(&conn->session->lock);
686         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
687         spin_unlock(&conn->session->lock);
688         return rc;
689 }
690 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
691 
692 /* verify itt (itt encoding: age+cid+itt) */
693 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
694                      uint32_t *ret_itt)
695 {
696         struct iscsi_session *session = conn->session;
697         struct iscsi_cmd_task *ctask;
698         uint32_t itt;
699 
700         if (hdr->itt != RESERVED_ITT) {
701                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
702                     (session->age << ISCSI_AGE_SHIFT)) {
703                         iscsi_conn_printk(KERN_ERR, conn,
704                                           "received itt %x expected session "
705                                           "age (%x)\n", (__force u32)hdr->itt,
706                                           session->age & ISCSI_AGE_MASK);
707                         return ISCSI_ERR_BAD_ITT;
708                 }
709 
710                 itt = get_itt(hdr->itt);
711         } else
712                 itt = ~0U;
713 
714         if (itt < session->cmds_max) {
715                 ctask = session->cmds[itt];
716 
717                 if (!ctask->sc) {
718                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
719                                           "with itt 0x%x\n", ctask->itt);
720                         /* force drop */
721                         return ISCSI_ERR_NO_SCSI_CMD;
722                 }
723 
724                 if (ctask->sc->SCp.phase != session->age) {
725                         iscsi_conn_printk(KERN_ERR, conn,
726                                           "iscsi: ctask's session age %d, "
727                                           "expected %d\n", ctask->sc->SCp.phase,
728                                           session->age);
729                         return ISCSI_ERR_SESSION_FAILED;
730                 }
731         }
732 
733         *ret_itt = itt;
734         return 0;
735 }
736 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
737 
738 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
739 {
740         struct iscsi_session *session = conn->session;
741         unsigned long flags;
742 
743         spin_lock_irqsave(&session->lock, flags);
744         if (session->state == ISCSI_STATE_FAILED) {
745                 spin_unlock_irqrestore(&session->lock, flags);
746                 return;
747         }
748 
749         if (conn->stop_stage == 0)
750                 session->state = ISCSI_STATE_FAILED;
751         spin_unlock_irqrestore(&session->lock, flags);
752         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
753         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
754         iscsi_conn_error(conn->cls_conn, err);
755 }
756 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
757 
758 static void iscsi_prep_mtask(struct iscsi_conn *conn,
759                              struct iscsi_mgmt_task *mtask)
760 {
761         struct iscsi_session *session = conn->session;
762         struct iscsi_hdr *hdr = mtask->hdr;
763         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
764 
765         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
766             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
767                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
768         /*
769          * pre-format CmdSN for outgoing PDU.
770          */
771         nop->cmdsn = cpu_to_be32(session->cmdsn);
772         if (hdr->itt != RESERVED_ITT) {
773                 hdr->itt = build_itt(mtask->itt, session->age);
774                 /*
775                  * TODO: We always use immediate, so we never hit this.
776                  * If we start to send tmfs or nops as non-immediate then
777                  * we should start checking the cmdsn numbers for mgmt tasks.
778                  */
779                 if (conn->c_stage == ISCSI_CONN_STARTED &&
780                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
781                         session->queued_cmdsn++;
782                         session->cmdsn++;
783                 }
784         }
785 
786         if (session->tt->init_mgmt_task)
787                 session->tt->init_mgmt_task(conn, mtask);
788 
789         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
790                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
791                    mtask->data_count);
792 }
793 
794 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
795 {
796         struct iscsi_hdr *hdr = conn->mtask->hdr;
797         int rc;
798 
799         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
800                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
801         spin_unlock_bh(&conn->session->lock);
802 
803         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
804         spin_lock_bh(&conn->session->lock);
805         if (rc)
806                 return rc;
807 
808         /* done with this in-progress mtask */
809         conn->mtask = NULL;
810         return 0;
811 }
812 
813 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
814 {
815         struct iscsi_session *session = conn->session;
816 
817         /*
818          * Check for iSCSI window and take care of CmdSN wrap-around
819          */
820         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
821                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
822                            "CmdSN %u/%u\n", session->exp_cmdsn,
823                            session->max_cmdsn, session->cmdsn,
824                            session->queued_cmdsn);
825                 return -ENOSPC;
826         }
827         return 0;
828 }
829 
830 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
831 {
832         struct iscsi_cmd_task *ctask = conn->ctask;
833         int rc;
834 
835         __iscsi_get_ctask(ctask);
836         spin_unlock_bh(&conn->session->lock);
837         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
838         spin_lock_bh(&conn->session->lock);
839         __iscsi_put_ctask(ctask);
840         if (!rc)
841                 /* done with this ctask */
842                 conn->ctask = NULL;
843         return rc;
844 }
845 
846 /**
847  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
848  * @ctask: ctask to requeue
849  *
850  * LLDs that need to run a ctask from the session workqueue should call
851  * this. The session lock must be held.
852  */
853 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
854 {
855         struct iscsi_conn *conn = ctask->conn;
856 
857         list_move_tail(&ctask->running, &conn->requeue);
858         scsi_queue_work(conn->session->host, &conn->xmitwork);
859 }
860 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
861 
862 /**
863  * iscsi_data_xmit - xmit any command into the scheduled connection
864  * @conn: iscsi connection
865  *
866  * Notes:
867  *      The function can return -EAGAIN in which case the caller must
868  *      re-schedule it again later or recover. '' return code means
869  *      successful xmit.
870  **/
871 static int iscsi_data_xmit(struct iscsi_conn *conn)
872 {
873         int rc = 0;
874 
875         spin_lock_bh(&conn->session->lock);
876         if (unlikely(conn->suspend_tx)) {
877                 debug_scsi("conn %d Tx suspended!\n", conn->id);
878                 spin_unlock_bh(&conn->session->lock);
879                 return -ENODATA;
880         }
881 
882         if (conn->ctask) {
883                 rc = iscsi_xmit_ctask(conn);
884                 if (rc)
885                         goto again;
886         }
887 
888         if (conn->mtask) {
889                 rc = iscsi_xmit_mtask(conn);
890                 if (rc)
891                         goto again;
892         }
893 
894         /*
895          * process mgmt pdus like nops before commands since we should
896          * only have one nop-out as a ping from us and targets should not
897          * overflow us with nop-ins
898          */
899 check_mgmt:
900         while (!list_empty(&conn->mgmtqueue)) {
901                 conn->mtask = list_entry(conn->mgmtqueue.next,
902                                          struct iscsi_mgmt_task, running);
903                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
904                         iscsi_free_mgmt_task(conn, conn->mtask);
905                         conn->mtask = NULL;
906                         continue;
907                 }
908 
909                 iscsi_prep_mtask(conn, conn->mtask);
910                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
911                 rc = iscsi_xmit_mtask(conn);
912                 if (rc)
913                         goto again;
914         }
915 
916         /* process pending command queue */
917         while (!list_empty(&conn->xmitqueue)) {
918                 if (conn->tmf_state == TMF_QUEUED)
919                         break;
920 
921                 conn->ctask = list_entry(conn->xmitqueue.next,
922                                          struct iscsi_cmd_task, running);
923                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
924                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
925                         continue;
926                 }
927                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
928                         fail_command(conn, conn->ctask, DID_ABORT << 16);
929                         continue;
930                 }
931 
932                 conn->ctask->state = ISCSI_TASK_RUNNING;
933                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
934                 rc = iscsi_xmit_ctask(conn);
935                 if (rc)
936                         goto again;
937                 /*
938                  * we could continuously get new ctask requests so
939                  * we need to check the mgmt queue for nops that need to
940                  * be sent to aviod starvation
941                  */
942                 if (!list_empty(&conn->mgmtqueue))
943                         goto check_mgmt;
944         }
945 
946         while (!list_empty(&conn->requeue)) {
947                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
948                         break;
949 
950                 /*
951                  * we always do fastlogout - conn stop code will clean up.
952                  */
953                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
954                         break;
955 
956                 conn->ctask = list_entry(conn->requeue.next,
957                                          struct iscsi_cmd_task, running);
958                 conn->ctask->state = ISCSI_TASK_RUNNING;
959                 list_move_tail(conn->requeue.next, &conn->run_list);
960                 rc = iscsi_xmit_ctask(conn);
961                 if (rc)
962                         goto again;
963                 if (!list_empty(&conn->mgmtqueue))
964                         goto check_mgmt;
965         }
966         spin_unlock_bh(&conn->session->lock);
967         return -ENODATA;
968 
969 again:
970         if (unlikely(conn->suspend_tx))
971                 rc = -ENODATA;
972         spin_unlock_bh(&conn->session->lock);
973         return rc;
974 }
975 
976 static void iscsi_xmitworker(struct work_struct *work)
977 {
978         struct iscsi_conn *conn =
979                 container_of(work, struct iscsi_conn, xmitwork);
980         int rc;
981         /*
982          * serialize Xmit worker on a per-connection basis.
983          */
984         do {
985                 rc = iscsi_data_xmit(conn);
986         } while (rc >= 0 || rc == -EAGAIN);
987 }
988 
989 enum {
990         FAILURE_BAD_HOST = 1,
991         FAILURE_SESSION_FAILED,
992         FAILURE_SESSION_FREED,
993         FAILURE_WINDOW_CLOSED,
994         FAILURE_OOM,
995         FAILURE_SESSION_TERMINATE,
996         FAILURE_SESSION_IN_RECOVERY,
997         FAILURE_SESSION_RECOVERY_TIMEOUT,
998         FAILURE_SESSION_LOGGING_OUT,
999         FAILURE_SESSION_NOT_READY,
1000 };
1001 
1002 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1003 {
1004         struct Scsi_Host *host;
1005         int reason = 0;
1006         struct iscsi_session *session;
1007         struct iscsi_conn *conn;
1008         struct iscsi_cmd_task *ctask = NULL;
1009 
1010         sc->scsi_done = done;
1011         sc->result = 0;
1012         sc->SCp.ptr = NULL;
1013 
1014         host = sc->device->host;
1015         spin_unlock(host->host_lock);
1016 
1017         session = iscsi_hostdata(host->hostdata);
1018         spin_lock(&session->lock);
1019 
1020         reason = iscsi_session_chkready(session_to_cls(session));
1021         if (reason) {
1022                 sc->result = reason;
1023                 goto fault;
1024         }
1025 
1026         /*
1027          * ISCSI_STATE_FAILED is a temp. state. The recovery
1028          * code will decide what is best to do with command queued
1029          * during this time
1030          */
1031         if (session->state != ISCSI_STATE_LOGGED_IN &&
1032             session->state != ISCSI_STATE_FAILED) {
1033                 /*
1034                  * to handle the race between when we set the recovery state
1035                  * and block the session we requeue here (commands could
1036                  * be entering our queuecommand while a block is starting
1037                  * up because the block code is not locked)
1038                  */
1039                 switch (session->state) {
1040                 case ISCSI_STATE_IN_RECOVERY:
1041                         reason = FAILURE_SESSION_IN_RECOVERY;
1042                         sc->result = DID_IMM_RETRY << 16;
1043                         break;
1044                 case ISCSI_STATE_LOGGING_OUT:
1045                         reason = FAILURE_SESSION_LOGGING_OUT;
1046                         sc->result = DID_IMM_RETRY << 16;
1047                         break;
1048                 case ISCSI_STATE_RECOVERY_FAILED:
1049                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1050                         sc->result = DID_NO_CONNECT << 16;
1051                         break;
1052                 case ISCSI_STATE_TERMINATE:
1053                         reason = FAILURE_SESSION_TERMINATE;
1054                         sc->result = DID_NO_CONNECT << 16;
1055                         break;
1056                 default:
1057                         reason = FAILURE_SESSION_FREED;
1058                         sc->result = DID_NO_CONNECT << 16;
1059                 }
1060                 goto fault;
1061         }
1062 
1063         conn = session->leadconn;
1064         if (!conn) {
1065                 reason = FAILURE_SESSION_FREED;
1066                 sc->result = DID_NO_CONNECT << 16;
1067                 goto fault;
1068         }
1069 
1070         if (iscsi_check_cmdsn_window_closed(conn)) {
1071                 reason = FAILURE_WINDOW_CLOSED;
1072                 goto reject;
1073         }
1074 
1075         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1076                          sizeof(void*))) {
1077                 reason = FAILURE_OOM;
1078                 goto reject;
1079         }
1080         session->queued_cmdsn++;
1081 
1082         sc->SCp.phase = session->age;
1083         sc->SCp.ptr = (char *)ctask;
1084 
1085         atomic_set(&ctask->refcount, 1);
1086         ctask->state = ISCSI_TASK_PENDING;
1087         ctask->conn = conn;
1088         ctask->sc = sc;
1089         INIT_LIST_HEAD(&ctask->running);
1090 
1091         list_add_tail(&ctask->running, &conn->xmitqueue);
1092         spin_unlock(&session->lock);
1093 
1094         scsi_queue_work(host, &conn->xmitwork);
1095         spin_lock(host->host_lock);
1096         return 0;
1097 
1098 reject:
1099         spin_unlock(&session->lock);
1100         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1101         spin_lock(host->host_lock);
1102         return SCSI_MLQUEUE_HOST_BUSY;
1103 
1104 fault:
1105         spin_unlock(&session->lock);
1106         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1107         scsi_set_resid(sc, scsi_bufflen(sc));
1108         sc->scsi_done(sc);
1109         spin_lock(host->host_lock);
1110         return 0;
1111 }
1112 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1113 
1114 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1115 {
1116         if (depth > ISCSI_MAX_CMD_PER_LUN)
1117                 depth = ISCSI_MAX_CMD_PER_LUN;
1118         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1119         return sdev->queue_depth;
1120 }
1121 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1122 
1123 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1124 {
1125         struct iscsi_session *session = class_to_transport_session(cls_session);
1126 
1127         spin_lock_bh(&session->lock);
1128         if (session->state != ISCSI_STATE_LOGGED_IN) {
1129                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1130                 if (session->leadconn)
1131                         wake_up(&session->leadconn->ehwait);
1132         }
1133         spin_unlock_bh(&session->lock);
1134 }
1135 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1136 
1137 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1138 {
1139         struct Scsi_Host *host = sc->device->host;
1140         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1141         struct iscsi_conn *conn = session->leadconn;
1142 
1143         mutex_lock(&session->eh_mutex);
1144         spin_lock_bh(&session->lock);
1145         if (session->state == ISCSI_STATE_TERMINATE) {
1146 failed:
1147                 debug_scsi("failing host reset: session terminated "
1148                            "[CID %d age %d]\n", conn->id, session->age);
1149                 spin_unlock_bh(&session->lock);
1150                 mutex_unlock(&session->eh_mutex);
1151                 return FAILED;
1152         }
1153 
1154         spin_unlock_bh(&session->lock);
1155         mutex_unlock(&session->eh_mutex);
1156         /*
1157          * we drop the lock here but the leadconn cannot be destoyed while
1158          * we are in the scsi eh
1159          */
1160         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1161 
1162         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1163         wait_event_interruptible(conn->ehwait,
1164                                  session->state == ISCSI_STATE_TERMINATE ||
1165                                  session->state == ISCSI_STATE_LOGGED_IN ||
1166                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1167         if (signal_pending(current))
1168                 flush_signals(current);
1169 
1170         mutex_lock(&session->eh_mutex);
1171         spin_lock_bh(&session->lock);
1172         if (session->state == ISCSI_STATE_LOGGED_IN)
1173                 iscsi_session_printk(KERN_INFO, session,
1174                                      "host reset succeeded\n");
1175         else
1176                 goto failed;
1177         spin_unlock_bh(&session->lock);
1178         mutex_unlock(&session->eh_mutex);
1179         return SUCCESS;
1180 }
1181 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1182 
1183 static void iscsi_tmf_timedout(unsigned long data)
1184 {
1185         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1186         struct iscsi_session *session = conn->session;
1187 
1188         spin_lock(&session->lock);
1189         if (conn->tmf_state == TMF_QUEUED) {
1190                 conn->tmf_state = TMF_TIMEDOUT;
1191                 debug_scsi("tmf timedout\n");
1192                 /* unblock eh_abort() */
1193                 wake_up(&conn->ehwait);
1194         }
1195         spin_unlock(&session->lock);
1196 }
1197 
1198 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1199                                    struct iscsi_tm *hdr, int age,
1200                                    int timeout)
1201 {
1202         struct iscsi_session *session = conn->session;
1203         struct iscsi_mgmt_task *mtask;
1204 
1205         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1206                                       NULL, 0);
1207         if (!mtask) {
1208                 spin_unlock_bh(&session->lock);
1209                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1210                 spin_lock_bh(&session->lock);
1211                 debug_scsi("tmf exec failure\n");
1212                 return -EPERM;
1213         }
1214         conn->tmfcmd_pdus_cnt++;
1215         conn->tmf_timer.expires = timeout * HZ + jiffies;
1216         conn->tmf_timer.function = iscsi_tmf_timedout;
1217         conn->tmf_timer.data = (unsigned long)conn;
1218         add_timer(&conn->tmf_timer);
1219         debug_scsi("tmf set timeout\n");
1220 
1221         spin_unlock_bh(&session->lock);
1222         mutex_unlock(&session->eh_mutex);
1223         scsi_queue_work(session->host, &conn->xmitwork);
1224 
1225         /*
1226          * block eh thread until:
1227          *
1228          * 1) tmf response
1229          * 2) tmf timeout
1230          * 3) session is terminated or restarted or userspace has
1231          * given up on recovery
1232          */
1233         wait_event_interruptible(conn->ehwait, age != session->age ||
1234                                  session->state != ISCSI_STATE_LOGGED_IN ||
1235                                  conn->tmf_state != TMF_QUEUED);
1236         if (signal_pending(current))
1237                 flush_signals(current);
1238         del_timer_sync(&conn->tmf_timer);
1239 
1240         mutex_lock(&session->eh_mutex);
1241         spin_lock_bh(&session->lock);
1242         /* if the session drops it will clean up the mtask */
1243         if (age != session->age ||
1244             session->state != ISCSI_STATE_LOGGED_IN)
1245                 return -ENOTCONN;
1246         return 0;
1247 }
1248 
1249 /*
1250  * Fail commands. session lock held and recv side suspended and xmit
1251  * thread flushed
1252  */
1253 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1254                               int error)
1255 {
1256         struct iscsi_cmd_task *ctask, *tmp;
1257 
1258         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1259                 conn->ctask = NULL;
1260 
1261         /* flush pending */
1262         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1263                 if (lun == ctask->sc->device->lun || lun == -1) {
1264                         debug_scsi("failing pending sc %p itt 0x%x\n",
1265                                    ctask->sc, ctask->itt);
1266                         fail_command(conn, ctask, error << 16);
1267                 }
1268         }
1269 
1270         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1271                 if (lun == ctask->sc->device->lun || lun == -1) {
1272                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1273                                    ctask->sc, ctask->itt);
1274                         fail_command(conn, ctask, error << 16);
1275                 }
1276         }
1277 
1278         /* fail all other running */
1279         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1280                 if (lun == ctask->sc->device->lun || lun == -1) {
1281                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1282                                    ctask->sc, ctask->itt);
1283                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1284                 }
1285         }
1286 }
1287 
1288 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1289 {
1290         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1291         scsi_flush_work(conn->session->host);
1292 }
1293 
1294 static void iscsi_start_tx(struct iscsi_conn *conn)
1295 {
1296         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1297         scsi_queue_work(conn->session->host, &conn->xmitwork);
1298 }
1299 
1300 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1301 {
1302         struct iscsi_cls_session *cls_session;
1303         struct iscsi_session *session;
1304         struct iscsi_conn *conn;
1305         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1306 
1307         cls_session = starget_to_session(scsi_target(scmd->device));
1308         session = class_to_transport_session(cls_session);
1309 
1310         debug_scsi("scsi cmd %p timedout\n", scmd);
1311 
1312         spin_lock(&session->lock);
1313         if (session->state != ISCSI_STATE_LOGGED_IN) {
1314                 /*
1315                  * We are probably in the middle of iscsi recovery so let
1316                  * that complete and handle the error.
1317                  */
1318                 rc = EH_RESET_TIMER;
1319                 goto done;
1320         }
1321 
1322         conn = session->leadconn;
1323         if (!conn) {
1324                 /* In the middle of shuting down */
1325                 rc = EH_RESET_TIMER;
1326                 goto done;
1327         }
1328 
1329         if (!conn->recv_timeout && !conn->ping_timeout)
1330                 goto done;
1331         /*
1332          * if the ping timedout then we are in the middle of cleaning up
1333          * and can let the iscsi eh handle it
1334          */
1335         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1336                             (conn->ping_timeout * HZ), jiffies))
1337                 rc = EH_RESET_TIMER;
1338         /*
1339          * if we are about to check the transport then give the command
1340          * more time
1341          */
1342         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1343                            jiffies))
1344                 rc = EH_RESET_TIMER;
1345         /* if in the middle of checking the transport then give us more time */
1346         if (conn->ping_mtask)
1347                 rc = EH_RESET_TIMER;
1348 done:
1349         spin_unlock(&session->lock);
1350         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1351         return rc;
1352 }
1353 
1354 static void iscsi_check_transport_timeouts(unsigned long data)
1355 {
1356         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1357         struct iscsi_session *session = conn->session;
1358         unsigned long recv_timeout, next_timeout = 0, last_recv;
1359 
1360         spin_lock(&session->lock);
1361         if (session->state != ISCSI_STATE_LOGGED_IN)
1362                 goto done;
1363 
1364         recv_timeout = conn->recv_timeout;
1365         if (!recv_timeout)
1366                 goto done;
1367 
1368         recv_timeout *= HZ;
1369         last_recv = conn->last_recv;
1370         if (conn->ping_mtask &&
1371             time_before_eq(conn->last_ping + (conn->ping_timeout * HZ),
1372                            jiffies)) {
1373                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1374                                   "expired, last rx %lu, last ping %lu, "
1375                                   "now %lu\n", conn->ping_timeout, last_recv,
1376                                   conn->last_ping, jiffies);
1377                 spin_unlock(&session->lock);
1378                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1379                 return;
1380         }
1381 
1382         if (time_before_eq(last_recv + recv_timeout, jiffies)) {
1383                 /* send a ping to try to provoke some traffic */
1384                 debug_scsi("Sending nopout as ping on conn %p\n", conn);
1385                 iscsi_send_nopout(conn, NULL);
1386                 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
1387         } else
1388                 next_timeout = last_recv + recv_timeout;
1389 
1390         debug_scsi("Setting next tmo %lu\n", next_timeout);
1391         mod_timer(&conn->transport_timer, next_timeout);
1392 done:
1393         spin_unlock(&session->lock);
1394 }
1395 
1396 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1397                                       struct iscsi_tm *hdr)
1398 {
1399         memset(hdr, 0, sizeof(*hdr));
1400         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1401         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1402         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1403         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1404         hdr->rtt = ctask->hdr->itt;
1405         hdr->refcmdsn = ctask->hdr->cmdsn;
1406 }
1407 
1408 int iscsi_eh_abort(struct scsi_cmnd *sc)
1409 {
1410         struct Scsi_Host *host = sc->device->host;
1411         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1412         struct iscsi_conn *conn;
1413         struct iscsi_cmd_task *ctask;
1414         struct iscsi_tm *hdr;
1415         int rc, age;
1416 
1417         mutex_lock(&session->eh_mutex);
1418         spin_lock_bh(&session->lock);
1419         /*
1420          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1421          * got the command.
1422          */
1423         if (!sc->SCp.ptr) {
1424                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1425                 spin_unlock_bh(&session->lock);
1426                 mutex_unlock(&session->eh_mutex);
1427                 return SUCCESS;
1428         }
1429 
1430         /*
1431          * If we are not logged in or we have started a new session
1432          * then let the host reset code handle this
1433          */
1434         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1435             sc->SCp.phase != session->age) {
1436                 spin_unlock_bh(&session->lock);
1437                 mutex_unlock(&session->eh_mutex);
1438                 return FAILED;
1439         }
1440 
1441         conn = session->leadconn;
1442         conn->eh_abort_cnt++;
1443         age = session->age;
1444 
1445         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1446         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1447 
1448         /* ctask completed before time out */
1449         if (!ctask->sc) {
1450                 debug_scsi("sc completed while abort in progress\n");
1451                 goto success;
1452         }
1453 
1454         if (ctask->state == ISCSI_TASK_PENDING) {
1455                 fail_command(conn, ctask, DID_ABORT << 16);
1456                 goto success;
1457         }
1458 
1459         /* only have one tmf outstanding at a time */
1460         if (conn->tmf_state != TMF_INITIAL)
1461                 goto failed;
1462         conn->tmf_state = TMF_QUEUED;
1463 
1464         hdr = &conn->tmhdr;
1465         iscsi_prep_abort_task_pdu(ctask, hdr);
1466 
1467         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1468                 rc = FAILED;
1469                 goto failed;
1470         }
1471 
1472         switch (conn->tmf_state) {
1473         case TMF_SUCCESS:
1474                 spin_unlock_bh(&session->lock);
1475                 iscsi_suspend_tx(conn);
1476                 /*
1477                  * clean up task if aborted. grab the recv lock as a writer
1478                  */
1479                 write_lock_bh(conn->recv_lock);
1480                 spin_lock(&session->lock);
1481                 fail_command(conn, ctask, DID_ABORT << 16);
1482                 conn->tmf_state = TMF_INITIAL;
1483                 spin_unlock(&session->lock);
1484                 write_unlock_bh(conn->recv_lock);
1485                 iscsi_start_tx(conn);
1486                 goto success_unlocked;
1487         case TMF_TIMEDOUT:
1488                 spin_unlock_bh(&session->lock);
1489                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1490                 goto failed_unlocked;
1491         case TMF_NOT_FOUND:
1492                 if (!sc->SCp.ptr) {
1493                         conn->tmf_state = TMF_INITIAL;
1494                         /* ctask completed before tmf abort response */
1495                         debug_scsi("sc completed while abort in progress\n");
1496                         goto success;
1497                 }
1498                 /* fall through */
1499         default:
1500                 conn->tmf_state = TMF_INITIAL;
1501                 goto failed;
1502         }
1503 
1504 success:
1505         spin_unlock_bh(&session->lock);
1506 success_unlocked:
1507         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1508         mutex_unlock(&session->eh_mutex);
1509         return SUCCESS;
1510 
1511 failed:
1512         spin_unlock_bh(&session->lock);
1513 failed_unlocked:
1514         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1515                     ctask ? ctask->itt : 0);
1516         mutex_unlock(&session->eh_mutex);
1517         return FAILED;
1518 }
1519 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1520 
1521 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1522 {
1523         memset(hdr, 0, sizeof(*hdr));
1524         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1525         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1526         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1527         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1528         hdr->rtt = RESERVED_ITT;
1529 }
1530 
1531 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1532 {
1533         struct Scsi_Host *host = sc->device->host;
1534         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1535         struct iscsi_conn *conn;
1536         struct iscsi_tm *hdr;
1537         int rc = FAILED;
1538 
1539         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1540 
1541         mutex_lock(&session->eh_mutex);
1542         spin_lock_bh(&session->lock);
1543         /*
1544          * Just check if we are not logged in. We cannot check for
1545          * the phase because the reset could come from a ioctl.
1546          */
1547         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1548                 goto unlock;
1549         conn = session->leadconn;
1550 
1551         /* only have one tmf outstanding at a time */
1552         if (conn->tmf_state != TMF_INITIAL)
1553                 goto unlock;
1554         conn->tmf_state = TMF_QUEUED;
1555 
1556         hdr = &conn->tmhdr;
1557         iscsi_prep_lun_reset_pdu(sc, hdr);
1558 
1559         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1560                                     session->lu_reset_timeout)) {
1561                 rc = FAILED;
1562                 goto unlock;
1563         }
1564 
1565         switch (conn->tmf_state) {
1566         case TMF_SUCCESS:
1567                 break;
1568         case TMF_TIMEDOUT:
1569                 spin_unlock_bh(&session->lock);
1570                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1571                 goto done;
1572         default:
1573                 conn->tmf_state = TMF_INITIAL;
1574                 goto unlock;
1575         }
1576 
1577         rc = SUCCESS;
1578         spin_unlock_bh(&session->lock);
1579 
1580         iscsi_suspend_tx(conn);
1581         /* need to grab the recv lock then session lock */
1582         write_lock_bh(conn->recv_lock);
1583         spin_lock(&session->lock);
1584         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1585         conn->tmf_state = TMF_INITIAL;
1586         spin_unlock(&session->lock);
1587         write_unlock_bh(conn->recv_lock);
1588 
1589         iscsi_start_tx(conn);
1590         goto done;
1591 
1592 unlock:
1593         spin_unlock_bh(&session->lock);
1594 done:
1595         debug_scsi("iscsi_eh_device_reset %s\n",
1596                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1597         mutex_unlock(&session->eh_mutex);
1598         return rc;
1599 }
1600 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1601 
1602 /*
1603  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1604  * should be accessed via kfifo_{get,put} on q->queue.
1605  * Optionally, the caller can obtain the array of object pointers
1606  * by passing in a non-NULL @items pointer
1607  */
1608 int
1609 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1610 {
1611         int i, num_arrays = 1;
1612 
1613         memset(q, 0, sizeof(*q));
1614 
1615         q->max = max;
1616 
1617         /* If the user passed an items pointer, he wants a copy of
1618          * the array. */
1619         if (items)
1620                 num_arrays++;
1621         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1622         if (q->pool == NULL)
1623                 goto enomem;
1624 
1625         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1626                               GFP_KERNEL, NULL);
1627         if (q->queue == ERR_PTR(-ENOMEM))
1628                 goto enomem;
1629 
1630         for (i = 0; i < max; i++) {
1631                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1632                 if (q->pool[i] == NULL) {
1633                         q->max = i;
1634                         goto enomem;
1635                 }
1636                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1637         }
1638 
1639         if (items) {
1640                 *items = q->pool + max;
1641                 memcpy(*items, q->pool, max * sizeof(void *));
1642         }
1643 
1644         return 0;
1645 
1646 enomem:
1647         iscsi_pool_free(q);
1648         return -ENOMEM;
1649 }
1650 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1651 
1652 void iscsi_pool_free(struct iscsi_pool *q)
1653 {
1654         int i;
1655 
1656         for (i = 0; i < q->max; i++)
1657                 kfree(q->pool[i]);
1658         if (q->pool)
1659                 kfree(q->pool);
1660 }
1661 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1662 
1663 /*
1664  * iSCSI Session's hostdata organization:
1665  *
1666  *    *------------------* <== hostdata_session(host->hostdata)
1667  *    | ptr to class sess|
1668  *    |------------------| <== iscsi_hostdata(host->hostdata)
1669  *    | iscsi_session    |
1670  *    *------------------*
1671  */
1672 
1673 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1674                                  _sz % sizeof(unsigned long))
1675 
1676 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1677 
1678 /**
1679  * iscsi_session_setup - create iscsi cls session and host and session
1680  * @scsit: scsi transport template
1681  * @iscsit: iscsi transport template
1682  * @cmds_max: scsi host can queue
1683  * @qdepth: scsi host cmds per lun
1684  * @cmd_task_size: LLD ctask private data size
1685  * @mgmt_task_size: LLD mtask private data size
1686  * @initial_cmdsn: initial CmdSN
1687  * @hostno: host no allocated
1688  *
1689  * This can be used by software iscsi_transports that allocate
1690  * a session per scsi host.
1691  **/
1692 struct iscsi_cls_session *
1693 iscsi_session_setup(struct iscsi_transport *iscsit,
1694                     struct scsi_transport_template *scsit,
1695                     uint16_t cmds_max, uint16_t qdepth,
1696                     int cmd_task_size, int mgmt_task_size,
1697                     uint32_t initial_cmdsn, uint32_t *hostno)
1698 {
1699         struct Scsi_Host *shost;
1700         struct iscsi_session *session;
1701         struct iscsi_cls_session *cls_session;
1702         int cmd_i;
1703 
1704         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1705                 if (qdepth != 0)
1706                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1707                               "Queue depth must be between 1 and %d.\n",
1708                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1709                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1710         }
1711 
1712         if (!is_power_of_2(cmds_max) || cmds_max >= ISCSI_MGMT_ITT_OFFSET ||
1713             cmds_max < 2) {
1714                 if (cmds_max != 0)
1715                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1716                                "can_queue must be a power of 2 and between "
1717                                "2 and %d - setting to %d.\n", cmds_max,
1718                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1719                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1720         }
1721 
1722         shost = scsi_host_alloc(iscsit->host_template,
1723                                 hostdata_privsize(sizeof(*session)));
1724         if (!shost)
1725                 return NULL;
1726 
1727         /* the iscsi layer takes one task for reserve */
1728         shost->can_queue = cmds_max - 1;
1729         shost->cmd_per_lun = qdepth;
1730         shost->max_id = 1;
1731         shost->max_channel = 0;
1732         shost->max_lun = iscsit->max_lun;
1733         shost->max_cmd_len = iscsit->max_cmd_len;
1734         shost->transportt = scsit;
1735         shost->transportt->create_work_queue = 1;
1736         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1737         *hostno = shost->host_no;
1738 
1739         session = iscsi_hostdata(shost->hostdata);
1740         memset(session, 0, sizeof(struct iscsi_session));
1741         session->host = shost;
1742         session->state = ISCSI_STATE_FREE;
1743         session->fast_abort = 1;
1744         session->lu_reset_timeout = 15;
1745         session->abort_timeout = 10;
1746         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1747         session->cmds_max = cmds_max;
1748         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1749         session->exp_cmdsn = initial_cmdsn + 1;
1750         session->max_cmdsn = initial_cmdsn + 1;
1751         session->max_r2t = 1;
1752         session->tt = iscsit;
1753         mutex_init(&session->eh_mutex);
1754 
1755         /* initialize SCSI PDU commands pool */
1756         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1757                             (void***)&session->cmds,
1758                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1759                 goto cmdpool_alloc_fail;
1760 
1761         /* pre-format cmds pool with ITT */
1762         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1763                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1764 
1765                 if (cmd_task_size)
1766                         ctask->dd_data = &ctask[1];
1767                 ctask->itt = cmd_i;
1768                 INIT_LIST_HEAD(&ctask->running);
1769         }
1770 
1771         spin_lock_init(&session->lock);
1772 
1773         /* initialize immediate command pool */
1774         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1775                            (void***)&session->mgmt_cmds,
1776                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1777                 goto mgmtpool_alloc_fail;
1778 
1779 
1780         /* pre-format immediate cmds pool with ITT */
1781         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1782                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1783 
1784                 if (mgmt_task_size)
1785                         mtask->dd_data = &mtask[1];
1786                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1787                 INIT_LIST_HEAD(&mtask->running);
1788         }
1789 
1790         if (scsi_add_host(shost, NULL))
1791                 goto add_host_fail;
1792 
1793         if (!try_module_get(iscsit->owner))
1794                 goto cls_session_fail;
1795 
1796         cls_session = iscsi_create_session(shost, iscsit, 0);
1797         if (!cls_session)
1798                 goto module_put;
1799         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1800 
1801         return cls_session;
1802 
1803 module_put:
1804         module_put(iscsit->owner);
1805 cls_session_fail:
1806         scsi_remove_host(shost);
1807 add_host_fail:
1808         iscsi_pool_free(&session->mgmtpool);
1809 mgmtpool_alloc_fail:
1810         iscsi_pool_free(&session->cmdpool);
1811 cmdpool_alloc_fail:
1812         scsi_host_put(shost);
1813         return NULL;
1814 }
1815 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1816 
1817 /**
1818  * iscsi_session_teardown - destroy session, host, and cls_session
1819  * shost: scsi host
1820  *
1821  * This can be used by software iscsi_transports that allocate
1822  * a session per scsi host.
1823  **/
1824 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1825 {
1826         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1827         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1828         struct module *owner = cls_session->transport->owner;
1829 
1830         iscsi_remove_session(cls_session);
1831         scsi_remove_host(shost);
1832 
1833         iscsi_pool_free(&session->mgmtpool);
1834         iscsi_pool_free(&session->cmdpool);
1835 
1836         kfree(session->password);
1837         kfree(session->password_in);
1838         kfree(session->username);
1839         kfree(session->username_in);
1840         kfree(session->targetname);
1841         kfree(session->netdev);
1842         kfree(session->hwaddress);
1843         kfree(session->initiatorname);
1844 
1845         iscsi_free_session(cls_session);
1846         scsi_host_put(shost);
1847         module_put(owner);
1848 }
1849 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1850 
1851 /**
1852  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1853  * @cls_session: iscsi_cls_session
1854  * @conn_idx: cid
1855  **/
1856 struct iscsi_cls_conn *
1857 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1858 {
1859         struct iscsi_session *session = class_to_transport_session(cls_session);
1860         struct iscsi_conn *conn;
1861         struct iscsi_cls_conn *cls_conn;
1862         char *data;
1863 
1864         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1865         if (!cls_conn)
1866                 return NULL;
1867         conn = cls_conn->dd_data;
1868         memset(conn, 0, sizeof(*conn));
1869 
1870         conn->session = session;
1871         conn->cls_conn = cls_conn;
1872         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1873         conn->id = conn_idx;
1874         conn->exp_statsn = 0;
1875         conn->tmf_state = TMF_INITIAL;
1876 
1877         init_timer(&conn->transport_timer);
1878         conn->transport_timer.data = (unsigned long)conn;
1879         conn->transport_timer.function = iscsi_check_transport_timeouts;
1880 
1881         INIT_LIST_HEAD(&conn->run_list);
1882         INIT_LIST_HEAD(&conn->mgmt_run_list);
1883         INIT_LIST_HEAD(&conn->mgmtqueue);
1884         INIT_LIST_HEAD(&conn->xmitqueue);
1885         INIT_LIST_HEAD(&conn->requeue);
1886         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1887 
1888         /* allocate login_mtask used for the login/text sequences */
1889         spin_lock_bh(&session->lock);
1890         if (!__kfifo_get(session->mgmtpool.queue,
1891                          (void*)&conn->login_mtask,
1892                          sizeof(void*))) {
1893                 spin_unlock_bh(&session->lock);
1894                 goto login_mtask_alloc_fail;
1895         }
1896         spin_unlock_bh(&session->lock);
1897 
1898         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1899         if (!data)
1900                 goto login_mtask_data_alloc_fail;
1901         conn->login_mtask->data = conn->data = data;
1902 
1903         init_timer(&conn->tmf_timer);
1904         init_waitqueue_head(&conn->ehwait);
1905 
1906         return cls_conn;
1907 
1908 login_mtask_data_alloc_fail:
1909         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1910                     sizeof(void*));
1911 login_mtask_alloc_fail:
1912         iscsi_destroy_conn(cls_conn);
1913         return NULL;
1914 }
1915 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1916 
1917 /**
1918  * iscsi_conn_teardown - teardown iscsi connection
1919  * cls_conn: iscsi class connection
1920  *
1921  * TODO: we may need to make this into a two step process
1922  * like scsi-mls remove + put host
1923  */
1924 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1925 {
1926         struct iscsi_conn *conn = cls_conn->dd_data;
1927         struct iscsi_session *session = conn->session;
1928         unsigned long flags;
1929 
1930         del_timer_sync(&conn->transport_timer);
1931 
1932         spin_lock_bh(&session->lock);
1933         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1934         if (session->leadconn == conn) {
1935                 /*
1936                  * leading connection? then give up on recovery.
1937                  */
1938                 session->state = ISCSI_STATE_TERMINATE;
1939                 wake_up(&conn->ehwait);
1940         }
1941         spin_unlock_bh(&session->lock);
1942 
1943         /*
1944          * Block until all in-progress commands for this connection
1945          * time out or fail.
1946          */
1947         for (;;) {
1948                 spin_lock_irqsave(session->host->host_lock, flags);
1949                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1950                         spin_unlock_irqrestore(session->host->host_lock, flags);
1951                         break;
1952                 }
1953                 spin_unlock_irqrestore(session->host->host_lock, flags);
1954                 msleep_interruptible(500);
1955                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
1956                                   "host_busy %d host_failed %d\n",
1957                                   session->host->host_busy,
1958                                   session->host->host_failed);
1959                 /*
1960                  * force eh_abort() to unblock
1961                  */
1962                 wake_up(&conn->ehwait);
1963         }
1964 
1965         /* flush queued up work because we free the connection below */
1966         iscsi_suspend_tx(conn);
1967 
1968         spin_lock_bh(&session->lock);
1969         kfree(conn->data);
1970         kfree(conn->persistent_address);
1971         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1972                     sizeof(void*));
1973         if (session->leadconn == conn)
1974                 session->leadconn = NULL;
1975         spin_unlock_bh(&session->lock);
1976 
1977         iscsi_destroy_conn(cls_conn);
1978 }
1979 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1980 
1981 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1982 {
1983         struct iscsi_conn *conn = cls_conn->dd_data;
1984         struct iscsi_session *session = conn->session;
1985 
1986         if (!session) {
1987                 iscsi_conn_printk(KERN_ERR, conn,
1988                                   "can't start unbound connection\n");
1989                 return -EPERM;
1990         }
1991 
1992         if ((session->imm_data_en || !session->initial_r2t_en) &&
1993              session->first_burst > session->max_burst) {
1994                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
1995                                   "first_burst %d max_burst %d\n",
1996                                   session->first_burst, session->max_burst);
1997                 return -EINVAL;
1998         }
1999 
2000         if (conn->ping_timeout && !conn->recv_timeout) {
2001                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2002                                   "zero. Using 5 seconds\n.");
2003                 conn->recv_timeout = 5;
2004         }
2005 
2006         if (conn->recv_timeout && !conn->ping_timeout) {
2007                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2008                                   "zero. Using 5 seconds.\n");
2009                 conn->ping_timeout = 5;
2010         }
2011 
2012         spin_lock_bh(&session->lock);
2013         conn->c_stage = ISCSI_CONN_STARTED;
2014         session->state = ISCSI_STATE_LOGGED_IN;
2015         session->queued_cmdsn = session->cmdsn;
2016 
2017         conn->last_recv = jiffies;
2018         conn->last_ping = jiffies;
2019         if (conn->recv_timeout && conn->ping_timeout)
2020                 mod_timer(&conn->transport_timer,
2021                           jiffies + (conn->recv_timeout * HZ));
2022 
2023         switch(conn->stop_stage) {
2024         case STOP_CONN_RECOVER:
2025                 /*
2026                  * unblock eh_abort() if it is blocked. re-try all
2027                  * commands after successful recovery
2028                  */
2029                 conn->stop_stage = 0;
2030                 conn->tmf_state = TMF_INITIAL;
2031                 session->age++;
2032                 if (session->age == 16)
2033                         session->age = 0;
2034                 break;
2035         case STOP_CONN_TERM:
2036                 conn->stop_stage = 0;
2037                 break;
2038         default:
2039                 break;
2040         }
2041         spin_unlock_bh(&session->lock);
2042 
2043         iscsi_unblock_session(session_to_cls(session));
2044         wake_up(&conn->ehwait);
2045         return 0;
2046 }
2047 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2048 
2049 static void
2050 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2051 {
2052         struct iscsi_mgmt_task *mtask, *tmp;
2053 
2054         /* handle pending */
2055         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2056                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2057                 iscsi_free_mgmt_task(conn, mtask);
2058         }
2059 
2060         /* handle running */
2061         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2062                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2063                 iscsi_free_mgmt_task(conn, mtask);
2064         }
2065 
2066         conn->mtask = NULL;
2067 }
2068 
2069 static void iscsi_start_session_recovery(struct iscsi_session *session,
2070                                          struct iscsi_conn *conn, int flag)
2071 {
2072         int old_stop_stage;
2073 
2074         del_timer_sync(&conn->transport_timer);
2075 
2076         mutex_lock(&session->eh_mutex);
2077         spin_lock_bh(&session->lock);
2078         if (conn->stop_stage == STOP_CONN_TERM) {
2079                 spin_unlock_bh(&session->lock);
2080                 mutex_unlock(&session->eh_mutex);
2081                 return;
2082         }
2083 
2084         /*
2085          * The LLD either freed/unset the lock on us, or userspace called
2086          * stop but did not create a proper connection (connection was never
2087          * bound or it was unbound then stop was called).
2088          */
2089         if (!conn->recv_lock) {
2090                 spin_unlock_bh(&session->lock);
2091                 mutex_unlock(&session->eh_mutex);
2092                 return;
2093         }
2094 
2095         /*
2096          * When this is called for the in_login state, we only want to clean
2097          * up the login task and connection. We do not need to block and set
2098          * the recovery state again
2099          */
2100         if (flag == STOP_CONN_TERM)
2101                 session->state = ISCSI_STATE_TERMINATE;
2102         else if (conn->stop_stage != STOP_CONN_RECOVER)
2103                 session->state = ISCSI_STATE_IN_RECOVERY;
2104 
2105         old_stop_stage = conn->stop_stage;
2106         conn->stop_stage = flag;
2107         conn->c_stage = ISCSI_CONN_STOPPED;
2108         spin_unlock_bh(&session->lock);
2109 
2110         iscsi_suspend_tx(conn);
2111 
2112         write_lock_bh(conn->recv_lock);
2113         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2114         write_unlock_bh(conn->recv_lock);
2115 
2116         /*
2117          * for connection level recovery we should not calculate
2118          * header digest. conn->hdr_size used for optimization
2119          * in hdr_extract() and will be re-negotiated at
2120          * set_param() time.
2121          */
2122         if (flag == STOP_CONN_RECOVER) {
2123                 conn->hdrdgst_en = 0;
2124                 conn->datadgst_en = 0;
2125                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2126                     old_stop_stage != STOP_CONN_RECOVER) {
2127                         debug_scsi("blocking session\n");
2128                         iscsi_block_session(session_to_cls(session));
2129                 }
2130         }
2131 
2132         /*
2133          * flush queues.
2134          */
2135         spin_lock_bh(&session->lock);
2136         fail_all_commands(conn, -1,
2137                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2138         flush_control_queues(session, conn);
2139         spin_unlock_bh(&session->lock);
2140         mutex_unlock(&session->eh_mutex);
2141 }
2142 
2143 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2144 {
2145         struct iscsi_conn *conn = cls_conn->dd_data;
2146         struct iscsi_session *session = conn->session;
2147 
2148         switch (flag) {
2149         case STOP_CONN_RECOVER:
2150         case STOP_CONN_TERM:
2151                 iscsi_start_session_recovery(session, conn, flag);
2152                 break;
2153         default:
2154                 iscsi_conn_printk(KERN_ERR, conn,
2155                                   "invalid stop flag %d\n", flag);
2156         }
2157 }
2158 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2159 
2160 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2161                     struct iscsi_cls_conn *cls_conn, int is_leading)
2162 {
2163         struct iscsi_session *session = class_to_transport_session(cls_session);
2164         struct iscsi_conn *conn = cls_conn->dd_data;
2165 
2166         spin_lock_bh(&session->lock);
2167         if (is_leading)
2168                 session->leadconn = conn;
2169         spin_unlock_bh(&session->lock);
2170 
2171         /*
2172          * Unblock xmitworker(), Login Phase will pass through.
2173          */
2174         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2175         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2176         return 0;
2177 }
2178 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2179 
2180 
2181 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2182                     enum iscsi_param param, char *buf, int buflen)
2183 {
2184         struct iscsi_conn *conn = cls_conn->dd_data;
2185         struct iscsi_session *session = conn->session;
2186         uint32_t value;
2187 
2188         switch(param) {
2189         case ISCSI_PARAM_FAST_ABORT:
2190                 sscanf(buf, "%d", &session->fast_abort);
2191                 break;
2192         case ISCSI_PARAM_ABORT_TMO:
2193                 sscanf(buf, "%d", &session->abort_timeout);
2194                 break;
2195         case ISCSI_PARAM_LU_RESET_TMO:
2196                 sscanf(buf, "%d", &session->lu_reset_timeout);
2197                 break;
2198         case ISCSI_PARAM_PING_TMO:
2199                 sscanf(buf, "%d", &conn->ping_timeout);
2200                 break;
2201         case ISCSI_PARAM_RECV_TMO:
2202                 sscanf(buf, "%d", &conn->recv_timeout);
2203                 break;
2204         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2205                 sscanf(buf, "%d", &conn->max_recv_dlength);
2206                 break;
2207         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2208                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2209                 break;
2210         case ISCSI_PARAM_HDRDGST_EN:
2211                 sscanf(buf, "%d", &conn->hdrdgst_en);
2212                 break;
2213         case ISCSI_PARAM_DATADGST_EN:
2214                 sscanf(buf, "%d", &conn->datadgst_en);
2215                 break;
2216         case ISCSI_PARAM_INITIAL_R2T_EN:
2217                 sscanf(buf, "%d", &session->initial_r2t_en);
2218                 break;
2219         case ISCSI_PARAM_MAX_R2T:
2220                 sscanf(buf, "%d", &session->max_r2t);
2221                 break;
2222         case ISCSI_PARAM_IMM_DATA_EN:
2223                 sscanf(buf, "%d", &session->imm_data_en);
2224                 break;
2225         case ISCSI_PARAM_FIRST_BURST:
2226                 sscanf(buf, "%d", &session->first_burst);
2227                 break;
2228         case ISCSI_PARAM_MAX_BURST:
2229                 sscanf(buf, "%d", &session->max_burst);
2230                 break;
2231         case ISCSI_PARAM_PDU_INORDER_EN:
2232                 sscanf(buf, "%d", &session->pdu_inorder_en);
2233                 break;
2234         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2235                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2236                 break;
2237         case ISCSI_PARAM_ERL:
2238                 sscanf(buf, "%d", &session->erl);
2239                 break;
2240         case ISCSI_PARAM_IFMARKER_EN:
2241                 sscanf(buf, "%d", &value);
2242                 BUG_ON(value);
2243                 break;
2244         case ISCSI_PARAM_OFMARKER_EN:
2245                 sscanf(buf, "%d", &value);
2246                 BUG_ON(value);
2247                 break;
2248         case ISCSI_PARAM_EXP_STATSN:
2249                 sscanf(buf, "%u", &conn->exp_statsn);
2250                 break;
2251         case ISCSI_PARAM_USERNAME:
2252                 kfree(session->username);
2253                 session->username = kstrdup(buf, GFP_KERNEL);
2254                 if (!session->username)
2255                         return -ENOMEM;
2256                 break;
2257         case ISCSI_PARAM_USERNAME_IN:
2258                 kfree(session->username_in);
2259                 session->username_in = kstrdup(buf, GFP_KERNEL);
2260                 if (!session->username_in)
2261                         return -ENOMEM;
2262                 break;
2263         case ISCSI_PARAM_PASSWORD:
2264                 kfree(session->password);
2265                 session->password = kstrdup(buf, GFP_KERNEL);
2266                 if (!session->password)
2267                         return -ENOMEM;
2268                 break;
2269         case ISCSI_PARAM_PASSWORD_IN:
2270                 kfree(session->password_in);
2271                 session->password_in = kstrdup(buf, GFP_KERNEL);
2272                 if (!session->password_in)
2273                         return -ENOMEM;
2274                 break;
2275         case ISCSI_PARAM_TARGET_NAME:
2276                 /* this should not change between logins */
2277                 if (session->targetname)
2278                         break;
2279 
2280                 session->targetname = kstrdup(buf, GFP_KERNEL);
2281                 if (!session->targetname)
2282                         return -ENOMEM;
2283                 break;
2284         case ISCSI_PARAM_TPGT:
2285                 sscanf(buf, "%d", &session->tpgt);
2286                 break;
2287         case ISCSI_PARAM_PERSISTENT_PORT:
2288                 sscanf(buf, "%d", &conn->persistent_port);
2289                 break;
2290         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2291                 /*
2292                  * this is the address returned in discovery so it should
2293                  * not change between logins.
2294                  */
2295                 if (conn->persistent_address)
2296                         break;
2297 
2298                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2299                 if (!conn->persistent_address)
2300                         return -ENOMEM;
2301                 break;
2302         default:
2303                 return -ENOSYS;
2304         }
2305 
2306         return 0;
2307 }
2308 EXPORT_SYMBOL_GPL(iscsi_set_param);
2309 
2310 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2311                             enum iscsi_param param, char *buf)
2312 {
2313         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2314         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2315         int len;
2316 
2317         switch(param) {
2318         case ISCSI_PARAM_FAST_ABORT:
2319                 len = sprintf(buf, "%d\n", session->fast_abort);
2320                 break;
2321         case ISCSI_PARAM_ABORT_TMO:
2322                 len = sprintf(buf, "%d\n", session->abort_timeout);
2323                 break;
2324         case ISCSI_PARAM_LU_RESET_TMO:
2325                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2326                 break;
2327         case ISCSI_PARAM_INITIAL_R2T_EN:
2328                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2329                 break;
2330         case ISCSI_PARAM_MAX_R2T:
2331                 len = sprintf(buf, "%hu\n", session->max_r2t);
2332                 break;
2333         case ISCSI_PARAM_IMM_DATA_EN:
2334                 len = sprintf(buf, "%d\n", session->imm_data_en);
2335                 break;
2336         case ISCSI_PARAM_FIRST_BURST:
2337                 len = sprintf(buf, "%u\n", session->first_burst);
2338                 break;
2339         case ISCSI_PARAM_MAX_BURST:
2340                 len = sprintf(buf, "%u\n", session->max_burst);
2341                 break;
2342         case ISCSI_PARAM_PDU_INORDER_EN:
2343                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2344                 break;
2345         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2346                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2347                 break;
2348         case ISCSI_PARAM_ERL:
2349                 len = sprintf(buf, "%d\n", session->erl);
2350                 break;
2351         case ISCSI_PARAM_TARGET_NAME:
2352                 len = sprintf(buf, "%s\n", session->targetname);
2353                 break;
2354         case ISCSI_PARAM_TPGT:
2355                 len = sprintf(buf, "%d\n", session->tpgt);
2356                 break;
2357         case ISCSI_PARAM_USERNAME:
2358                 len = sprintf(buf, "%s\n", session->username);
2359                 break;
2360         case ISCSI_PARAM_USERNAME_IN:
2361                 len = sprintf(buf, "%s\n", session->username_in);
2362                 break;
2363         case ISCSI_PARAM_PASSWORD:
2364                 len = sprintf(buf, "%s\n", session->password);
2365                 break;
2366         case ISCSI_PARAM_PASSWORD_IN:
2367                 len = sprintf(buf, "%s\n", session->password_in);
2368                 break;
2369         default:
2370                 return -ENOSYS;
2371         }
2372 
2373         return len;
2374 }
2375 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2376 
2377 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2378                          enum iscsi_param param, char *buf)
2379 {
2380         struct iscsi_conn *conn = cls_conn->dd_data;
2381         int len;
2382 
2383         switch(param) {
2384         case ISCSI_PARAM_PING_TMO:
2385                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2386                 break;
2387         case ISCSI_PARAM_RECV_TMO:
2388                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2389                 break;
2390         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2391                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2392                 break;
2393         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2394                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2395                 break;
2396         case ISCSI_PARAM_HDRDGST_EN:
2397                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2398                 break;
2399         case ISCSI_PARAM_DATADGST_EN:
2400                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2401                 break;
2402         case ISCSI_PARAM_IFMARKER_EN:
2403                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2404                 break;
2405         case ISCSI_PARAM_OFMARKER_EN:
2406                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2407                 break;
2408         case ISCSI_PARAM_EXP_STATSN:
2409                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2410                 break;
2411         case ISCSI_PARAM_PERSISTENT_PORT:
2412                 len = sprintf(buf, "%d\n", conn->persistent_port);
2413                 break;
2414         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2415                 len = sprintf(buf, "%s\n", conn->persistent_address);
2416                 break;
2417         default:
2418                 return -ENOSYS;
2419         }
2420 
2421         return len;
2422 }
2423 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2424 
2425 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2426                          char *buf)
2427 {
2428         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2429         int len;
2430 
2431         switch (param) {
2432         case ISCSI_HOST_PARAM_NETDEV_NAME:
2433                 if (!session->netdev)
2434                         len = sprintf(buf, "%s\n", "default");
2435                 else
2436                         len = sprintf(buf, "%s\n", session->netdev);
2437                 break;
2438         case ISCSI_HOST_PARAM_HWADDRESS:
2439                 if (!session->hwaddress)
2440                         len = sprintf(buf, "%s\n", "default");
2441                 else
2442                         len = sprintf(buf, "%s\n", session->hwaddress);
2443                 break;
2444         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2445                 if (!session->initiatorname)
2446                         len = sprintf(buf, "%s\n", "unknown");
2447                 else
2448                         len = sprintf(buf, "%s\n", session->initiatorname);
2449                 break;
2450 
2451         default:
2452                 return -ENOSYS;
2453         }
2454 
2455         return len;
2456 }
2457 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2458 
2459 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2460                          char *buf, int buflen)
2461 {
2462         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2463 
2464         switch (param) {
2465         case ISCSI_HOST_PARAM_NETDEV_NAME:
2466                 if (!session->netdev)
2467                         session->netdev = kstrdup(buf, GFP_KERNEL);
2468                 break;
2469         case ISCSI_HOST_PARAM_HWADDRESS:
2470                 if (!session->hwaddress)
2471                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2472                 break;
2473         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2474                 if (!session->initiatorname)
2475                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2476                 break;
2477         default:
2478                 return -ENOSYS;
2479         }
2480 
2481         return 0;
2482 }
2483 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2484 
2485 MODULE_AUTHOR("Mike Christie");
2486 MODULE_DESCRIPTION("iSCSI library functions");
2487 MODULE_LICENSE("GPL");
2488 
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