GNU Linux-libre 4.19.263-gnu1
[releases.git] / drivers / target / iscsi / iscsi_target_erl1.c
1 /*******************************************************************************
2  * This file contains error recovery level one used by the iSCSI Target driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18
19 #include <linux/list.h>
20 #include <linux/slab.h>
21 #include <scsi/iscsi_proto.h>
22 #include <target/target_core_base.h>
23 #include <target/target_core_fabric.h>
24 #include <target/iscsi/iscsi_transport.h>
25
26 #include <target/iscsi/iscsi_target_core.h>
27 #include "iscsi_target_seq_pdu_list.h"
28 #include "iscsi_target_datain_values.h"
29 #include "iscsi_target_device.h"
30 #include "iscsi_target_tpg.h"
31 #include "iscsi_target_util.h"
32 #include "iscsi_target_erl0.h"
33 #include "iscsi_target_erl1.h"
34 #include "iscsi_target_erl2.h"
35 #include "iscsi_target.h"
36
37 #define OFFLOAD_BUF_SIZE        32768U
38
39 /*
40  *      Used to dump excess datain payload for certain error recovery
41  *      situations.  Receive in OFFLOAD_BUF_SIZE max of datain per rx_data().
42  *
43  *      dump_padding_digest denotes if padding and data digests need
44  *      to be dumped.
45  */
46 int iscsit_dump_data_payload(
47         struct iscsi_conn *conn,
48         u32 buf_len,
49         int dump_padding_digest)
50 {
51         char *buf, pad_bytes[4];
52         int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got;
53         u32 length, padding, offset = 0, size;
54         struct kvec iov;
55
56         if (conn->sess->sess_ops->RDMAExtensions)
57                 return 0;
58
59         length = min(buf_len, OFFLOAD_BUF_SIZE);
60
61         buf = kzalloc(length, GFP_ATOMIC);
62         if (!buf) {
63                 pr_err("Unable to allocate %u bytes for offload"
64                                 " buffer.\n", length);
65                 return -1;
66         }
67         memset(&iov, 0, sizeof(struct kvec));
68
69         while (offset < buf_len) {
70                 size = min(buf_len - offset, length);
71
72                 iov.iov_len = size;
73                 iov.iov_base = buf;
74
75                 rx_got = rx_data(conn, &iov, 1, size);
76                 if (rx_got != size) {
77                         ret = DATAOUT_CANNOT_RECOVER;
78                         goto out;
79                 }
80
81                 offset += size;
82         }
83
84         if (!dump_padding_digest)
85                 goto out;
86
87         padding = ((-buf_len) & 3);
88         if (padding != 0) {
89                 iov.iov_len = padding;
90                 iov.iov_base = pad_bytes;
91
92                 rx_got = rx_data(conn, &iov, 1, padding);
93                 if (rx_got != padding) {
94                         ret = DATAOUT_CANNOT_RECOVER;
95                         goto out;
96                 }
97         }
98
99         if (conn->conn_ops->DataDigest) {
100                 u32 data_crc;
101
102                 iov.iov_len = ISCSI_CRC_LEN;
103                 iov.iov_base = &data_crc;
104
105                 rx_got = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
106                 if (rx_got != ISCSI_CRC_LEN) {
107                         ret = DATAOUT_CANNOT_RECOVER;
108                         goto out;
109                 }
110         }
111
112 out:
113         kfree(buf);
114         return ret;
115 }
116
117 /*
118  *      Used for retransmitting R2Ts from a R2T SNACK request.
119  */
120 static int iscsit_send_recovery_r2t_for_snack(
121         struct iscsi_cmd *cmd,
122         struct iscsi_r2t *r2t)
123 {
124         /*
125          * If the struct iscsi_r2t has not been sent yet, we can safely
126          * ignore retransmission
127          * of the R2TSN in question.
128          */
129         spin_lock_bh(&cmd->r2t_lock);
130         if (!r2t->sent_r2t) {
131                 spin_unlock_bh(&cmd->r2t_lock);
132                 return 0;
133         }
134         r2t->sent_r2t = 0;
135         spin_unlock_bh(&cmd->r2t_lock);
136
137         iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
138
139         return 0;
140 }
141
142 static int iscsit_handle_r2t_snack(
143         struct iscsi_cmd *cmd,
144         unsigned char *buf,
145         u32 begrun,
146         u32 runlength)
147 {
148         u32 last_r2tsn;
149         struct iscsi_r2t *r2t;
150
151         /*
152          * Make sure the initiator is not requesting retransmission
153          * of R2TSNs already acknowledged by a TMR TASK_REASSIGN.
154          */
155         if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
156             (begrun <= cmd->acked_data_sn)) {
157                 pr_err("ITT: 0x%08x, R2T SNACK requesting"
158                         " retransmission of R2TSN: 0x%08x to 0x%08x but already"
159                         " acked to  R2TSN: 0x%08x by TMR TASK_REASSIGN,"
160                         " protocol error.\n", cmd->init_task_tag, begrun,
161                         (begrun + runlength), cmd->acked_data_sn);
162
163                 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
164         }
165
166         if (runlength) {
167                 if ((begrun + runlength) > cmd->r2t_sn) {
168                         pr_err("Command ITT: 0x%08x received R2T SNACK"
169                         " with BegRun: 0x%08x, RunLength: 0x%08x, exceeds"
170                         " current R2TSN: 0x%08x, protocol error.\n",
171                         cmd->init_task_tag, begrun, runlength, cmd->r2t_sn);
172                         return iscsit_reject_cmd(cmd,
173                                         ISCSI_REASON_BOOKMARK_INVALID, buf);
174                 }
175                 last_r2tsn = (begrun + runlength);
176         } else
177                 last_r2tsn = cmd->r2t_sn;
178
179         while (begrun < last_r2tsn) {
180                 r2t = iscsit_get_holder_for_r2tsn(cmd, begrun);
181                 if (!r2t)
182                         return -1;
183                 if (iscsit_send_recovery_r2t_for_snack(cmd, r2t) < 0)
184                         return -1;
185
186                 begrun++;
187         }
188
189         return 0;
190 }
191
192 /*
193  *      Generates Offsets and NextBurstLength based on Begrun and Runlength
194  *      carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
195  *
196  *      For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only.
197  *
198  *      FIXME: How is this handled for a RData SNACK?
199  */
200 int iscsit_create_recovery_datain_values_datasequenceinorder_yes(
201         struct iscsi_cmd *cmd,
202         struct iscsi_datain_req *dr)
203 {
204         u32 data_sn = 0, data_sn_count = 0;
205         u32 pdu_start = 0, seq_no = 0;
206         u32 begrun = dr->begrun;
207         struct iscsi_conn *conn = cmd->conn;
208
209         while (begrun > data_sn++) {
210                 data_sn_count++;
211                 if ((dr->next_burst_len +
212                      conn->conn_ops->MaxRecvDataSegmentLength) <
213                      conn->sess->sess_ops->MaxBurstLength) {
214                         dr->read_data_done +=
215                                 conn->conn_ops->MaxRecvDataSegmentLength;
216                         dr->next_burst_len +=
217                                 conn->conn_ops->MaxRecvDataSegmentLength;
218                 } else {
219                         dr->read_data_done +=
220                                 (conn->sess->sess_ops->MaxBurstLength -
221                                  dr->next_burst_len);
222                         dr->next_burst_len = 0;
223                         pdu_start += data_sn_count;
224                         data_sn_count = 0;
225                         seq_no++;
226                 }
227         }
228
229         if (!conn->sess->sess_ops->DataPDUInOrder) {
230                 cmd->seq_no = seq_no;
231                 cmd->pdu_start = pdu_start;
232                 cmd->pdu_send_order = data_sn_count;
233         }
234
235         return 0;
236 }
237
238 /*
239  *      Generates Offsets and NextBurstLength based on Begrun and Runlength
240  *      carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
241  *
242  *      For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only.
243  *
244  *      FIXME: How is this handled for a RData SNACK?
245  */
246 int iscsit_create_recovery_datain_values_datasequenceinorder_no(
247         struct iscsi_cmd *cmd,
248         struct iscsi_datain_req *dr)
249 {
250         int found_seq = 0, i;
251         u32 data_sn, read_data_done = 0, seq_send_order = 0;
252         u32 begrun = dr->begrun;
253         u32 runlength = dr->runlength;
254         struct iscsi_conn *conn = cmd->conn;
255         struct iscsi_seq *first_seq = NULL, *seq = NULL;
256
257         if (!cmd->seq_list) {
258                 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
259                 return -1;
260         }
261
262         /*
263          * Calculate read_data_done for all sequences containing a
264          * first_datasn and last_datasn less than the BegRun.
265          *
266          * Locate the struct iscsi_seq the BegRun lies within and calculate
267          * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength.
268          *
269          * Also use struct iscsi_seq->seq_send_order to determine where to start.
270          */
271         for (i = 0; i < cmd->seq_count; i++) {
272                 seq = &cmd->seq_list[i];
273
274                 if (!seq->seq_send_order)
275                         first_seq = seq;
276
277                 /*
278                  * No data has been transferred for this DataIN sequence, so the
279                  * seq->first_datasn and seq->last_datasn have not been set.
280                  */
281                 if (!seq->sent) {
282                         pr_err("Ignoring non-sent sequence 0x%08x ->"
283                                 " 0x%08x\n\n", seq->first_datasn,
284                                 seq->last_datasn);
285                         continue;
286                 }
287
288                 /*
289                  * This DataIN sequence is precedes the received BegRun, add the
290                  * total xfer_len of the sequence to read_data_done and reset
291                  * seq->pdu_send_order.
292                  */
293                 if ((seq->first_datasn < begrun) &&
294                                 (seq->last_datasn < begrun)) {
295                         pr_err("Pre BegRun sequence 0x%08x ->"
296                                 " 0x%08x\n", seq->first_datasn,
297                                 seq->last_datasn);
298
299                         read_data_done += cmd->seq_list[i].xfer_len;
300                         seq->next_burst_len = seq->pdu_send_order = 0;
301                         continue;
302                 }
303
304                 /*
305                  * The BegRun lies within this DataIN sequence.
306                  */
307                 if ((seq->first_datasn <= begrun) &&
308                                 (seq->last_datasn >= begrun)) {
309                         pr_err("Found sequence begrun: 0x%08x in"
310                                 " 0x%08x -> 0x%08x\n", begrun,
311                                 seq->first_datasn, seq->last_datasn);
312
313                         seq_send_order = seq->seq_send_order;
314                         data_sn = seq->first_datasn;
315                         seq->next_burst_len = seq->pdu_send_order = 0;
316                         found_seq = 1;
317
318                         /*
319                          * For DataPDUInOrder=Yes, while the first DataSN of
320                          * the sequence is less than the received BegRun, add
321                          * the MaxRecvDataSegmentLength to read_data_done and
322                          * to the sequence's next_burst_len;
323                          *
324                          * For DataPDUInOrder=No, while the first DataSN of the
325                          * sequence is less than the received BegRun, find the
326                          * struct iscsi_pdu of the DataSN in question and add the
327                          * MaxRecvDataSegmentLength to read_data_done and to the
328                          * sequence's next_burst_len;
329                          */
330                         if (conn->sess->sess_ops->DataPDUInOrder) {
331                                 while (data_sn < begrun) {
332                                         seq->pdu_send_order++;
333                                         read_data_done +=
334                                                 conn->conn_ops->MaxRecvDataSegmentLength;
335                                         seq->next_burst_len +=
336                                                 conn->conn_ops->MaxRecvDataSegmentLength;
337                                         data_sn++;
338                                 }
339                         } else {
340                                 int j;
341                                 struct iscsi_pdu *pdu;
342
343                                 while (data_sn < begrun) {
344                                         seq->pdu_send_order++;
345
346                                         for (j = 0; j < seq->pdu_count; j++) {
347                                                 pdu = &cmd->pdu_list[
348                                                         seq->pdu_start + j];
349                                                 if (pdu->data_sn == data_sn) {
350                                                         read_data_done +=
351                                                                 pdu->length;
352                                                         seq->next_burst_len +=
353                                                                 pdu->length;
354                                                 }
355                                         }
356                                         data_sn++;
357                                 }
358                         }
359                         continue;
360                 }
361
362                 /*
363                  * This DataIN sequence is larger than the received BegRun,
364                  * reset seq->pdu_send_order and continue.
365                  */
366                 if ((seq->first_datasn > begrun) ||
367                                 (seq->last_datasn > begrun)) {
368                         pr_err("Post BegRun sequence 0x%08x -> 0x%08x\n",
369                                         seq->first_datasn, seq->last_datasn);
370
371                         seq->next_burst_len = seq->pdu_send_order = 0;
372                         continue;
373                 }
374         }
375
376         if (!found_seq) {
377                 if (!begrun) {
378                         if (!first_seq) {
379                                 pr_err("ITT: 0x%08x, Begrun: 0x%08x"
380                                         " but first_seq is NULL\n",
381                                         cmd->init_task_tag, begrun);
382                                 return -1;
383                         }
384                         seq_send_order = first_seq->seq_send_order;
385                         seq->next_burst_len = seq->pdu_send_order = 0;
386                         goto done;
387                 }
388
389                 pr_err("Unable to locate struct iscsi_seq for ITT: 0x%08x,"
390                         " BegRun: 0x%08x, RunLength: 0x%08x while"
391                         " DataSequenceInOrder=No and DataPDUInOrder=%s.\n",
392                                 cmd->init_task_tag, begrun, runlength,
393                         (conn->sess->sess_ops->DataPDUInOrder) ? "Yes" : "No");
394                 return -1;
395         }
396
397 done:
398         dr->read_data_done = read_data_done;
399         dr->seq_send_order = seq_send_order;
400
401         return 0;
402 }
403
404 static int iscsit_handle_recovery_datain(
405         struct iscsi_cmd *cmd,
406         unsigned char *buf,
407         u32 begrun,
408         u32 runlength)
409 {
410         struct iscsi_conn *conn = cmd->conn;
411         struct iscsi_datain_req *dr;
412         struct se_cmd *se_cmd = &cmd->se_cmd;
413
414         if (!(se_cmd->transport_state & CMD_T_COMPLETE)) {
415                 pr_err("Ignoring ITT: 0x%08x Data SNACK\n",
416                                 cmd->init_task_tag);
417                 return 0;
418         }
419
420         /*
421          * Make sure the initiator is not requesting retransmission
422          * of DataSNs already acknowledged by a Data ACK SNACK.
423          */
424         if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
425             (begrun <= cmd->acked_data_sn)) {
426                 pr_err("ITT: 0x%08x, Data SNACK requesting"
427                         " retransmission of DataSN: 0x%08x to 0x%08x but"
428                         " already acked to DataSN: 0x%08x by Data ACK SNACK,"
429                         " protocol error.\n", cmd->init_task_tag, begrun,
430                         (begrun + runlength), cmd->acked_data_sn);
431
432                 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
433         }
434
435         /*
436          * Make sure BegRun and RunLength in the Data SNACK are sane.
437          * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent.
438          */
439         if ((begrun + runlength) > (cmd->data_sn - 1)) {
440                 pr_err("Initiator requesting BegRun: 0x%08x, RunLength"
441                         ": 0x%08x greater than maximum DataSN: 0x%08x.\n",
442                                 begrun, runlength, (cmd->data_sn - 1));
443                 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID,
444                                          buf);
445         }
446
447         dr = iscsit_allocate_datain_req();
448         if (!dr)
449                 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
450                                          buf);
451
452         dr->data_sn = dr->begrun = begrun;
453         dr->runlength = runlength;
454         dr->generate_recovery_values = 1;
455         dr->recovery = DATAIN_WITHIN_COMMAND_RECOVERY;
456
457         iscsit_attach_datain_req(cmd, dr);
458
459         cmd->i_state = ISTATE_SEND_DATAIN;
460         iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
461
462         return 0;
463 }
464
465 int iscsit_handle_recovery_datain_or_r2t(
466         struct iscsi_conn *conn,
467         unsigned char *buf,
468         itt_t init_task_tag,
469         u32 targ_xfer_tag,
470         u32 begrun,
471         u32 runlength)
472 {
473         struct iscsi_cmd *cmd;
474
475         cmd = iscsit_find_cmd_from_itt(conn, init_task_tag);
476         if (!cmd)
477                 return 0;
478
479         /*
480          * FIXME: This will not work for bidi commands.
481          */
482         switch (cmd->data_direction) {
483         case DMA_TO_DEVICE:
484                 return iscsit_handle_r2t_snack(cmd, buf, begrun, runlength);
485         case DMA_FROM_DEVICE:
486                 return iscsit_handle_recovery_datain(cmd, buf, begrun,
487                                 runlength);
488         default:
489                 pr_err("Unknown cmd->data_direction: 0x%02x\n",
490                                 cmd->data_direction);
491                 return -1;
492         }
493
494         return 0;
495 }
496
497 /* #warning FIXME: Status SNACK needs to be dependent on OPCODE!!! */
498 int iscsit_handle_status_snack(
499         struct iscsi_conn *conn,
500         itt_t init_task_tag,
501         u32 targ_xfer_tag,
502         u32 begrun,
503         u32 runlength)
504 {
505         struct iscsi_cmd *cmd = NULL;
506         u32 last_statsn;
507         int found_cmd;
508
509         if (!begrun) {
510                 begrun = conn->exp_statsn;
511         } else if (conn->exp_statsn > begrun) {
512                 pr_err("Got Status SNACK Begrun: 0x%08x, RunLength:"
513                         " 0x%08x but already got ExpStatSN: 0x%08x on CID:"
514                         " %hu.\n", begrun, runlength, conn->exp_statsn,
515                         conn->cid);
516                 return 0;
517         }
518
519         last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength);
520
521         while (begrun < last_statsn) {
522                 found_cmd = 0;
523
524                 spin_lock_bh(&conn->cmd_lock);
525                 list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
526                         if (cmd->stat_sn == begrun) {
527                                 found_cmd = 1;
528                                 break;
529                         }
530                 }
531                 spin_unlock_bh(&conn->cmd_lock);
532
533                 if (!found_cmd) {
534                         pr_err("Unable to find StatSN: 0x%08x for"
535                                 " a Status SNACK, assuming this was a"
536                                 " protactic SNACK for an untransmitted"
537                                 " StatSN, ignoring.\n", begrun);
538                         begrun++;
539                         continue;
540                 }
541
542                 spin_lock_bh(&cmd->istate_lock);
543                 if (cmd->i_state == ISTATE_SEND_DATAIN) {
544                         spin_unlock_bh(&cmd->istate_lock);
545                         pr_err("Ignoring Status SNACK for BegRun:"
546                                 " 0x%08x, RunLength: 0x%08x, assuming this was"
547                                 " a protactic SNACK for an untransmitted"
548                                 " StatSN\n", begrun, runlength);
549                         begrun++;
550                         continue;
551                 }
552                 spin_unlock_bh(&cmd->istate_lock);
553
554                 cmd->i_state = ISTATE_SEND_STATUS_RECOVERY;
555                 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
556                 begrun++;
557         }
558
559         return 0;
560 }
561
562 int iscsit_handle_data_ack(
563         struct iscsi_conn *conn,
564         u32 targ_xfer_tag,
565         u32 begrun,
566         u32 runlength)
567 {
568         struct iscsi_cmd *cmd = NULL;
569
570         cmd = iscsit_find_cmd_from_ttt(conn, targ_xfer_tag);
571         if (!cmd) {
572                 pr_err("Data ACK SNACK for TTT: 0x%08x is"
573                         " invalid.\n", targ_xfer_tag);
574                 return -1;
575         }
576
577         if (begrun <= cmd->acked_data_sn) {
578                 pr_err("ITT: 0x%08x Data ACK SNACK BegRUN: 0x%08x is"
579                         " less than the already acked DataSN: 0x%08x.\n",
580                         cmd->init_task_tag, begrun, cmd->acked_data_sn);
581                 return -1;
582         }
583
584         /*
585          * For Data ACK SNACK, BegRun is the next expected DataSN.
586          * (see iSCSI v19: 10.16.6)
587          */
588         cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
589         cmd->acked_data_sn = (begrun - 1);
590
591         pr_debug("Received Data ACK SNACK for ITT: 0x%08x,"
592                 " updated acked DataSN to 0x%08x.\n",
593                         cmd->init_task_tag, cmd->acked_data_sn);
594
595         return 0;
596 }
597
598 static int iscsit_send_recovery_r2t(
599         struct iscsi_cmd *cmd,
600         u32 offset,
601         u32 xfer_len)
602 {
603         int ret;
604
605         spin_lock_bh(&cmd->r2t_lock);
606         ret = iscsit_add_r2t_to_list(cmd, offset, xfer_len, 1, 0);
607         spin_unlock_bh(&cmd->r2t_lock);
608
609         return ret;
610 }
611
612 int iscsit_dataout_datapduinorder_no_fbit(
613         struct iscsi_cmd *cmd,
614         struct iscsi_pdu *pdu)
615 {
616         int i, send_recovery_r2t = 0, recovery = 0;
617         u32 length = 0, offset = 0, pdu_count = 0, xfer_len = 0;
618         struct iscsi_conn *conn = cmd->conn;
619         struct iscsi_pdu *first_pdu = NULL;
620
621         /*
622          * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count
623          * of the DataOUT sequence.
624          */
625         if (conn->sess->sess_ops->DataSequenceInOrder) {
626                 for (i = 0; i < cmd->pdu_count; i++) {
627                         if (cmd->pdu_list[i].seq_no == pdu->seq_no) {
628                                 if (!first_pdu)
629                                         first_pdu = &cmd->pdu_list[i];
630                                 xfer_len += cmd->pdu_list[i].length;
631                                 pdu_count++;
632                         } else if (pdu_count)
633                                 break;
634                 }
635         } else {
636                 struct iscsi_seq *seq = cmd->seq_ptr;
637
638                 first_pdu = &cmd->pdu_list[seq->pdu_start];
639                 pdu_count = seq->pdu_count;
640         }
641
642         if (!first_pdu || !pdu_count)
643                 return DATAOUT_CANNOT_RECOVER;
644
645         /*
646          * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu.
647          * The following ugly logic does batching of not received PDUs.
648          */
649         for (i = 0; i < pdu_count; i++) {
650                 if (first_pdu[i].status == ISCSI_PDU_RECEIVED_OK) {
651                         if (!send_recovery_r2t)
652                                 continue;
653
654                         if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
655                                 return DATAOUT_CANNOT_RECOVER;
656
657                         send_recovery_r2t = length = offset = 0;
658                         continue;
659                 }
660                 /*
661                  * Set recovery = 1 for any missing, CRC failed, or timed
662                  * out PDUs to let the DataOUT logic know that this sequence
663                  * has not been completed yet.
664                  *
665                  * Also, only send a Recovery R2T for ISCSI_PDU_NOT_RECEIVED.
666                  * We assume if the PDU either failed CRC or timed out
667                  * that a Recovery R2T has already been sent.
668                  */
669                 recovery = 1;
670
671                 if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED)
672                         continue;
673
674                 if (!offset)
675                         offset = first_pdu[i].offset;
676                 length += first_pdu[i].length;
677
678                 send_recovery_r2t = 1;
679         }
680
681         if (send_recovery_r2t)
682                 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
683                         return DATAOUT_CANNOT_RECOVER;
684
685         return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY;
686 }
687
688 static int iscsit_recalculate_dataout_values(
689         struct iscsi_cmd *cmd,
690         u32 pdu_offset,
691         u32 pdu_length,
692         u32 *r2t_offset,
693         u32 *r2t_length)
694 {
695         int i;
696         struct iscsi_conn *conn = cmd->conn;
697         struct iscsi_pdu *pdu = NULL;
698
699         if (conn->sess->sess_ops->DataSequenceInOrder) {
700                 cmd->data_sn = 0;
701
702                 if (conn->sess->sess_ops->DataPDUInOrder) {
703                         *r2t_offset = cmd->write_data_done;
704                         *r2t_length = (cmd->seq_end_offset -
705                                         cmd->write_data_done);
706                         return 0;
707                 }
708
709                 *r2t_offset = cmd->seq_start_offset;
710                 *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset);
711
712                 for (i = 0; i < cmd->pdu_count; i++) {
713                         pdu = &cmd->pdu_list[i];
714
715                         if (pdu->status != ISCSI_PDU_RECEIVED_OK)
716                                 continue;
717
718                         if ((pdu->offset >= cmd->seq_start_offset) &&
719                            ((pdu->offset + pdu->length) <=
720                              cmd->seq_end_offset)) {
721                                 if (!cmd->unsolicited_data)
722                                         cmd->next_burst_len -= pdu->length;
723                                 else
724                                         cmd->first_burst_len -= pdu->length;
725
726                                 cmd->write_data_done -= pdu->length;
727                                 pdu->status = ISCSI_PDU_NOT_RECEIVED;
728                         }
729                 }
730         } else {
731                 struct iscsi_seq *seq = NULL;
732
733                 seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length);
734                 if (!seq)
735                         return -1;
736
737                 *r2t_offset = seq->orig_offset;
738                 *r2t_length = seq->xfer_len;
739
740                 cmd->write_data_done -= (seq->offset - seq->orig_offset);
741                 if (cmd->immediate_data)
742                         cmd->first_burst_len = cmd->write_data_done;
743
744                 seq->data_sn = 0;
745                 seq->offset = seq->orig_offset;
746                 seq->next_burst_len = 0;
747                 seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY;
748
749                 if (conn->sess->sess_ops->DataPDUInOrder)
750                         return 0;
751
752                 for (i = 0; i < seq->pdu_count; i++) {
753                         pdu = &cmd->pdu_list[i+seq->pdu_start];
754
755                         if (pdu->status != ISCSI_PDU_RECEIVED_OK)
756                                 continue;
757
758                         pdu->status = ISCSI_PDU_NOT_RECEIVED;
759                 }
760         }
761
762         return 0;
763 }
764
765 int iscsit_recover_dataout_sequence(
766         struct iscsi_cmd *cmd,
767         u32 pdu_offset,
768         u32 pdu_length)
769 {
770         u32 r2t_length = 0, r2t_offset = 0;
771
772         spin_lock_bh(&cmd->istate_lock);
773         cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
774         spin_unlock_bh(&cmd->istate_lock);
775
776         if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
777                         &r2t_offset, &r2t_length) < 0)
778                 return DATAOUT_CANNOT_RECOVER;
779
780         iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length);
781
782         return DATAOUT_WITHIN_COMMAND_RECOVERY;
783 }
784
785 static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void)
786 {
787         struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL;
788
789         ooo_cmdsn = kmem_cache_zalloc(lio_ooo_cache, GFP_ATOMIC);
790         if (!ooo_cmdsn) {
791                 pr_err("Unable to allocate memory for"
792                         " struct iscsi_ooo_cmdsn.\n");
793                 return NULL;
794         }
795         INIT_LIST_HEAD(&ooo_cmdsn->ooo_list);
796
797         return ooo_cmdsn;
798 }
799
800 /*
801  *      Called with sess->cmdsn_mutex held.
802  */
803 static int iscsit_attach_ooo_cmdsn(
804         struct iscsi_session *sess,
805         struct iscsi_ooo_cmdsn *ooo_cmdsn)
806 {
807         struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp;
808         /*
809          * We attach the struct iscsi_ooo_cmdsn entry to the out of order
810          * list in increasing CmdSN order.
811          * This allows iscsi_execute_ooo_cmdsns() to detect any
812          * additional CmdSN holes while performing delayed execution.
813          */
814         if (list_empty(&sess->sess_ooo_cmdsn_list))
815                 list_add_tail(&ooo_cmdsn->ooo_list,
816                                 &sess->sess_ooo_cmdsn_list);
817         else {
818                 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
819                                 typeof(*ooo_tail), ooo_list);
820                 /*
821                  * CmdSN is greater than the tail of the list.
822                  */
823                 if (iscsi_sna_lt(ooo_tail->cmdsn, ooo_cmdsn->cmdsn))
824                         list_add_tail(&ooo_cmdsn->ooo_list,
825                                         &sess->sess_ooo_cmdsn_list);
826                 else {
827                         /*
828                          * CmdSN is either lower than the head,  or somewhere
829                          * in the middle.
830                          */
831                         list_for_each_entry(ooo_tmp, &sess->sess_ooo_cmdsn_list,
832                                                 ooo_list) {
833                                 if (iscsi_sna_lt(ooo_tmp->cmdsn, ooo_cmdsn->cmdsn))
834                                         continue;
835
836                                 /* Insert before this entry */
837                                 list_add(&ooo_cmdsn->ooo_list,
838                                         ooo_tmp->ooo_list.prev);
839                                 break;
840                         }
841                 }
842         }
843
844         return 0;
845 }
846
847 /*
848  *      Removes an struct iscsi_ooo_cmdsn from a session's list,
849  *      called with struct iscsi_session->cmdsn_mutex held.
850  */
851 void iscsit_remove_ooo_cmdsn(
852         struct iscsi_session *sess,
853         struct iscsi_ooo_cmdsn *ooo_cmdsn)
854 {
855         list_del(&ooo_cmdsn->ooo_list);
856         kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
857 }
858
859 void iscsit_clear_ooo_cmdsns_for_conn(struct iscsi_conn *conn)
860 {
861         struct iscsi_ooo_cmdsn *ooo_cmdsn;
862         struct iscsi_session *sess = conn->sess;
863
864         mutex_lock(&sess->cmdsn_mutex);
865         list_for_each_entry(ooo_cmdsn, &sess->sess_ooo_cmdsn_list, ooo_list) {
866                 if (ooo_cmdsn->cid != conn->cid)
867                         continue;
868
869                 ooo_cmdsn->cmd = NULL;
870         }
871         mutex_unlock(&sess->cmdsn_mutex);
872 }
873
874 /*
875  *      Called with sess->cmdsn_mutex held.
876  */
877 int iscsit_execute_ooo_cmdsns(struct iscsi_session *sess)
878 {
879         int ooo_count = 0;
880         struct iscsi_cmd *cmd = NULL;
881         struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
882
883         list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
884                                 &sess->sess_ooo_cmdsn_list, ooo_list) {
885                 if (ooo_cmdsn->cmdsn != sess->exp_cmd_sn)
886                         continue;
887
888                 if (!ooo_cmdsn->cmd) {
889                         sess->exp_cmd_sn++;
890                         iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
891                         continue;
892                 }
893
894                 cmd = ooo_cmdsn->cmd;
895                 cmd->i_state = cmd->deferred_i_state;
896                 ooo_count++;
897                 sess->exp_cmd_sn++;
898                 pr_debug("Executing out of order CmdSN: 0x%08x,"
899                         " incremented ExpCmdSN to 0x%08x.\n",
900                         cmd->cmd_sn, sess->exp_cmd_sn);
901
902                 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
903
904                 if (iscsit_execute_cmd(cmd, 1) < 0)
905                         return -1;
906
907                 continue;
908         }
909
910         return ooo_count;
911 }
912
913 /*
914  *      Called either:
915  *
916  *      1. With sess->cmdsn_mutex held from iscsi_execute_ooo_cmdsns()
917  *      or iscsi_check_received_cmdsn().
918  *      2. With no locks held directly from iscsi_handle_XXX_pdu() functions
919  *      for immediate commands.
920  */
921 int iscsit_execute_cmd(struct iscsi_cmd *cmd, int ooo)
922 {
923         struct se_cmd *se_cmd = &cmd->se_cmd;
924         struct iscsi_conn *conn = cmd->conn;
925         int lr = 0;
926
927         spin_lock_bh(&cmd->istate_lock);
928         if (ooo)
929                 cmd->cmd_flags &= ~ICF_OOO_CMDSN;
930
931         switch (cmd->iscsi_opcode) {
932         case ISCSI_OP_SCSI_CMD:
933                 /*
934                  * Go ahead and send the CHECK_CONDITION status for
935                  * any SCSI CDB exceptions that may have occurred.
936                  */
937                 if (cmd->sense_reason) {
938                         if (cmd->sense_reason == TCM_RESERVATION_CONFLICT) {
939                                 cmd->i_state = ISTATE_SEND_STATUS;
940                                 spin_unlock_bh(&cmd->istate_lock);
941                                 iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
942                                                 cmd->i_state);
943                                 return 0;
944                         }
945                         spin_unlock_bh(&cmd->istate_lock);
946                         /*
947                          * Determine if delayed TASK_ABORTED status for WRITEs
948                          * should be sent now if no unsolicited data out
949                          * payloads are expected, or if the delayed status
950                          * should be sent after unsolicited data out with
951                          * ISCSI_FLAG_CMD_FINAL set in iscsi_handle_data_out()
952                          */
953                         if (transport_check_aborted_status(se_cmd,
954                                         (cmd->unsolicited_data == 0)) != 0)
955                                 return 0;
956                         /*
957                          * Otherwise send CHECK_CONDITION and sense for
958                          * exception
959                          */
960                         return transport_send_check_condition_and_sense(se_cmd,
961                                         cmd->sense_reason, 0);
962                 }
963                 /*
964                  * Special case for delayed CmdSN with Immediate
965                  * Data and/or Unsolicited Data Out attached.
966                  */
967                 if (cmd->immediate_data) {
968                         if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
969                                 spin_unlock_bh(&cmd->istate_lock);
970                                 target_execute_cmd(&cmd->se_cmd);
971                                 return 0;
972                         }
973                         spin_unlock_bh(&cmd->istate_lock);
974
975                         if (!(cmd->cmd_flags &
976                                         ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
977                                 /*
978                                  * Send the delayed TASK_ABORTED status for
979                                  * WRITEs if no more unsolicitied data is
980                                  * expected.
981                                  */
982                                 if (transport_check_aborted_status(se_cmd, 1)
983                                                 != 0)
984                                         return 0;
985
986                                 iscsit_set_dataout_sequence_values(cmd);
987                                 conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
988                         }
989                         return 0;
990                 }
991                 /*
992                  * The default handler.
993                  */
994                 spin_unlock_bh(&cmd->istate_lock);
995
996                 if ((cmd->data_direction == DMA_TO_DEVICE) &&
997                     !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
998                         /*
999                          * Send the delayed TASK_ABORTED status for WRITEs if
1000                          * no more nsolicitied data is expected.
1001                          */
1002                         if (transport_check_aborted_status(se_cmd, 1) != 0)
1003                                 return 0;
1004
1005                         iscsit_set_unsoliticed_dataout(cmd);
1006                 }
1007                 return transport_handle_cdb_direct(&cmd->se_cmd);
1008
1009         case ISCSI_OP_NOOP_OUT:
1010         case ISCSI_OP_TEXT:
1011                 spin_unlock_bh(&cmd->istate_lock);
1012                 iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
1013                 break;
1014         case ISCSI_OP_SCSI_TMFUNC:
1015                 if (cmd->se_cmd.se_tmr_req->response) {
1016                         spin_unlock_bh(&cmd->istate_lock);
1017                         iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
1018                                         cmd->i_state);
1019                         return 0;
1020                 }
1021                 spin_unlock_bh(&cmd->istate_lock);
1022
1023                 return transport_generic_handle_tmr(&cmd->se_cmd);
1024         case ISCSI_OP_LOGOUT:
1025                 spin_unlock_bh(&cmd->istate_lock);
1026                 switch (cmd->logout_reason) {
1027                 case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
1028                         lr = iscsit_logout_closesession(cmd, cmd->conn);
1029                         break;
1030                 case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
1031                         lr = iscsit_logout_closeconnection(cmd, cmd->conn);
1032                         break;
1033                 case ISCSI_LOGOUT_REASON_RECOVERY:
1034                         lr = iscsit_logout_removeconnforrecovery(cmd, cmd->conn);
1035                         break;
1036                 default:
1037                         pr_err("Unknown iSCSI Logout Request Code:"
1038                                 " 0x%02x\n", cmd->logout_reason);
1039                         return -1;
1040                 }
1041
1042                 return lr;
1043         default:
1044                 spin_unlock_bh(&cmd->istate_lock);
1045                 pr_err("Cannot perform out of order execution for"
1046                 " unknown iSCSI Opcode: 0x%02x\n", cmd->iscsi_opcode);
1047                 return -1;
1048         }
1049
1050         return 0;
1051 }
1052
1053 void iscsit_free_all_ooo_cmdsns(struct iscsi_session *sess)
1054 {
1055         struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
1056
1057         mutex_lock(&sess->cmdsn_mutex);
1058         list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
1059                         &sess->sess_ooo_cmdsn_list, ooo_list) {
1060
1061                 list_del(&ooo_cmdsn->ooo_list);
1062                 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1063         }
1064         mutex_unlock(&sess->cmdsn_mutex);
1065 }
1066
1067 int iscsit_handle_ooo_cmdsn(
1068         struct iscsi_session *sess,
1069         struct iscsi_cmd *cmd,
1070         u32 cmdsn)
1071 {
1072         int batch = 0;
1073         struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL;
1074
1075         cmd->deferred_i_state           = cmd->i_state;
1076         cmd->i_state                    = ISTATE_DEFERRED_CMD;
1077         cmd->cmd_flags                  |= ICF_OOO_CMDSN;
1078
1079         if (list_empty(&sess->sess_ooo_cmdsn_list))
1080                 batch = 1;
1081         else {
1082                 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
1083                                 typeof(*ooo_tail), ooo_list);
1084                 if (ooo_tail->cmdsn != (cmdsn - 1))
1085                         batch = 1;
1086         }
1087
1088         ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
1089         if (!ooo_cmdsn)
1090                 return -ENOMEM;
1091
1092         ooo_cmdsn->cmd                  = cmd;
1093         ooo_cmdsn->batch_count          = (batch) ?
1094                                           (cmdsn - sess->exp_cmd_sn) : 1;
1095         ooo_cmdsn->cid                  = cmd->conn->cid;
1096         ooo_cmdsn->exp_cmdsn            = sess->exp_cmd_sn;
1097         ooo_cmdsn->cmdsn                = cmdsn;
1098
1099         if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
1100                 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1101                 return -ENOMEM;
1102         }
1103
1104         return 0;
1105 }
1106
1107 static int iscsit_set_dataout_timeout_values(
1108         struct iscsi_cmd *cmd,
1109         u32 *offset,
1110         u32 *length)
1111 {
1112         struct iscsi_conn *conn = cmd->conn;
1113         struct iscsi_r2t *r2t;
1114
1115         if (cmd->unsolicited_data) {
1116                 *offset = 0;
1117                 *length = (conn->sess->sess_ops->FirstBurstLength >
1118                            cmd->se_cmd.data_length) ?
1119                            cmd->se_cmd.data_length :
1120                            conn->sess->sess_ops->FirstBurstLength;
1121                 return 0;
1122         }
1123
1124         spin_lock_bh(&cmd->r2t_lock);
1125         if (list_empty(&cmd->cmd_r2t_list)) {
1126                 pr_err("cmd->cmd_r2t_list is empty!\n");
1127                 spin_unlock_bh(&cmd->r2t_lock);
1128                 return -1;
1129         }
1130
1131         list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
1132                 if (r2t->sent_r2t && !r2t->recovery_r2t && !r2t->seq_complete) {
1133                         *offset = r2t->offset;
1134                         *length = r2t->xfer_len;
1135                         spin_unlock_bh(&cmd->r2t_lock);
1136                         return 0;
1137                 }
1138         }
1139         spin_unlock_bh(&cmd->r2t_lock);
1140
1141         pr_err("Unable to locate any incomplete DataOUT"
1142                 " sequences for ITT: 0x%08x.\n", cmd->init_task_tag);
1143
1144         return -1;
1145 }
1146
1147 /*
1148  *      NOTE: Called from interrupt (timer) context.
1149  */
1150 void iscsit_handle_dataout_timeout(struct timer_list *t)
1151 {
1152         u32 pdu_length = 0, pdu_offset = 0;
1153         u32 r2t_length = 0, r2t_offset = 0;
1154         struct iscsi_cmd *cmd = from_timer(cmd, t, dataout_timer);
1155         struct iscsi_conn *conn = cmd->conn;
1156         struct iscsi_session *sess = NULL;
1157         struct iscsi_node_attrib *na;
1158
1159         iscsit_inc_conn_usage_count(conn);
1160
1161         spin_lock_bh(&cmd->dataout_timeout_lock);
1162         if (cmd->dataout_timer_flags & ISCSI_TF_STOP) {
1163                 spin_unlock_bh(&cmd->dataout_timeout_lock);
1164                 iscsit_dec_conn_usage_count(conn);
1165                 return;
1166         }
1167         cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1168         sess = conn->sess;
1169         na = iscsit_tpg_get_node_attrib(sess);
1170
1171         if (!sess->sess_ops->ErrorRecoveryLevel) {
1172                 pr_debug("Unable to recover from DataOut timeout while"
1173                         " in ERL=0.\n");
1174                 goto failure;
1175         }
1176
1177         if (++cmd->dataout_timeout_retries == na->dataout_timeout_retries) {
1178                 pr_debug("Command ITT: 0x%08x exceeded max retries"
1179                         " for DataOUT timeout %u, closing iSCSI connection.\n",
1180                         cmd->init_task_tag, na->dataout_timeout_retries);
1181                 goto failure;
1182         }
1183
1184         cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
1185
1186         if (conn->sess->sess_ops->DataSequenceInOrder) {
1187                 if (conn->sess->sess_ops->DataPDUInOrder) {
1188                         pdu_offset = cmd->write_data_done;
1189                         if ((pdu_offset + (conn->sess->sess_ops->MaxBurstLength -
1190                              cmd->next_burst_len)) > cmd->se_cmd.data_length)
1191                                 pdu_length = (cmd->se_cmd.data_length -
1192                                         cmd->write_data_done);
1193                         else
1194                                 pdu_length = (conn->sess->sess_ops->MaxBurstLength -
1195                                                 cmd->next_burst_len);
1196                 } else {
1197                         pdu_offset = cmd->seq_start_offset;
1198                         pdu_length = (cmd->seq_end_offset -
1199                                 cmd->seq_start_offset);
1200                 }
1201         } else {
1202                 if (iscsit_set_dataout_timeout_values(cmd, &pdu_offset,
1203                                 &pdu_length) < 0)
1204                         goto failure;
1205         }
1206
1207         if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
1208                         &r2t_offset, &r2t_length) < 0)
1209                 goto failure;
1210
1211         pr_debug("Command ITT: 0x%08x timed out waiting for"
1212                 " completion of %sDataOUT Sequence Offset: %u, Length: %u\n",
1213                 cmd->init_task_tag, (cmd->unsolicited_data) ? "Unsolicited " :
1214                 "", r2t_offset, r2t_length);
1215
1216         if (iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length) < 0)
1217                 goto failure;
1218
1219         iscsit_start_dataout_timer(cmd, conn);
1220         spin_unlock_bh(&cmd->dataout_timeout_lock);
1221         iscsit_dec_conn_usage_count(conn);
1222
1223         return;
1224
1225 failure:
1226         spin_unlock_bh(&cmd->dataout_timeout_lock);
1227         iscsit_cause_connection_reinstatement(conn, 0);
1228         iscsit_dec_conn_usage_count(conn);
1229 }
1230
1231 void iscsit_mod_dataout_timer(struct iscsi_cmd *cmd)
1232 {
1233         struct iscsi_conn *conn = cmd->conn;
1234         struct iscsi_session *sess = conn->sess;
1235         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1236
1237         spin_lock_bh(&cmd->dataout_timeout_lock);
1238         if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1239                 spin_unlock_bh(&cmd->dataout_timeout_lock);
1240                 return;
1241         }
1242
1243         mod_timer(&cmd->dataout_timer,
1244                 (get_jiffies_64() + na->dataout_timeout * HZ));
1245         pr_debug("Updated DataOUT timer for ITT: 0x%08x",
1246                         cmd->init_task_tag);
1247         spin_unlock_bh(&cmd->dataout_timeout_lock);
1248 }
1249
1250 /*
1251  *      Called with cmd->dataout_timeout_lock held.
1252  */
1253 void iscsit_start_dataout_timer(
1254         struct iscsi_cmd *cmd,
1255         struct iscsi_conn *conn)
1256 {
1257         struct iscsi_session *sess = conn->sess;
1258         struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1259
1260         if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING)
1261                 return;
1262
1263         pr_debug("Starting DataOUT timer for ITT: 0x%08x on"
1264                 " CID: %hu.\n", cmd->init_task_tag, conn->cid);
1265
1266         cmd->dataout_timer_flags &= ~ISCSI_TF_STOP;
1267         cmd->dataout_timer_flags |= ISCSI_TF_RUNNING;
1268         mod_timer(&cmd->dataout_timer, jiffies + na->dataout_timeout * HZ);
1269 }
1270
1271 void iscsit_stop_dataout_timer(struct iscsi_cmd *cmd)
1272 {
1273         spin_lock_bh(&cmd->dataout_timeout_lock);
1274         if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1275                 spin_unlock_bh(&cmd->dataout_timeout_lock);
1276                 return;
1277         }
1278         cmd->dataout_timer_flags |= ISCSI_TF_STOP;
1279         spin_unlock_bh(&cmd->dataout_timeout_lock);
1280
1281         del_timer_sync(&cmd->dataout_timer);
1282
1283         spin_lock_bh(&cmd->dataout_timeout_lock);
1284         cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1285         pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n",
1286                         cmd->init_task_tag);
1287         spin_unlock_bh(&cmd->dataout_timeout_lock);
1288 }
1289 EXPORT_SYMBOL(iscsit_stop_dataout_timer);