1// SPDX-License-Identifier: GPL-2.0-or-later
2/*******************************************************************************
3 * This file contains error recovery level one used by the iSCSI Target driver.
4 *
5 * (c) Copyright 2007-2013 Datera, Inc.
6 *
7 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
8 *
9 ******************************************************************************/
10
11#include <linux/list.h>
12#include <linux/slab.h>
13#include <scsi/iscsi_proto.h>
14#include <target/target_core_base.h>
15#include <target/target_core_fabric.h>
16#include <target/iscsi/iscsi_transport.h>
17
18#include <target/iscsi/iscsi_target_core.h>
19#include "iscsi_target_seq_pdu_list.h"
20#include "iscsi_target_datain_values.h"
21#include "iscsi_target_device.h"
22#include "iscsi_target_tpg.h"
23#include "iscsi_target_util.h"
24#include "iscsi_target_erl0.h"
25#include "iscsi_target_erl1.h"
26#include "iscsi_target_erl2.h"
27#include "iscsi_target.h"
28
29#define OFFLOAD_BUF_SIZE 32768U
30
31/*
32 * Used to dump excess datain payload for certain error recovery
33 * situations. Receive in OFFLOAD_BUF_SIZE max of datain per rx_data().
34 *
35 * dump_padding_digest denotes if padding and data digests need
36 * to be dumped.
37 */
38int iscsit_dump_data_payload(
39 struct iscsit_conn *conn,
40 u32 buf_len,
41 int dump_padding_digest)
42{
43 char *buf;
44 int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got;
45 u32 length, offset = 0, size;
46 struct kvec iov;
47
48 if (conn->sess->sess_ops->RDMAExtensions)
49 return 0;
50
51 if (dump_padding_digest) {
52 buf_len = ALIGN(buf_len, 4);
53 if (conn->conn_ops->DataDigest)
54 buf_len += ISCSI_CRC_LEN;
55 }
56
57 length = min(buf_len, OFFLOAD_BUF_SIZE);
58
59 buf = kzalloc(size: length, GFP_ATOMIC);
60 if (!buf) {
61 pr_err("Unable to allocate %u bytes for offload"
62 " buffer.\n", length);
63 return -1;
64 }
65 memset(&iov, 0, sizeof(struct kvec));
66
67 while (offset < buf_len) {
68 size = min(buf_len - offset, length);
69
70 iov.iov_len = size;
71 iov.iov_base = buf;
72
73 rx_got = rx_data(conn, &iov, 1, size);
74 if (rx_got != size) {
75 ret = DATAOUT_CANNOT_RECOVER;
76 break;
77 }
78
79 offset += size;
80 }
81
82 kfree(objp: buf);
83 return ret;
84}
85
86/*
87 * Used for retransmitting R2Ts from a R2T SNACK request.
88 */
89static int iscsit_send_recovery_r2t_for_snack(
90 struct iscsit_cmd *cmd,
91 struct iscsi_r2t *r2t)
92{
93 /*
94 * If the struct iscsi_r2t has not been sent yet, we can safely
95 * ignore retransmission
96 * of the R2TSN in question.
97 */
98 spin_lock_bh(lock: &cmd->r2t_lock);
99 if (!r2t->sent_r2t) {
100 spin_unlock_bh(lock: &cmd->r2t_lock);
101 return 0;
102 }
103 r2t->sent_r2t = 0;
104 spin_unlock_bh(lock: &cmd->r2t_lock);
105
106 iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
107
108 return 0;
109}
110
111static int iscsit_handle_r2t_snack(
112 struct iscsit_cmd *cmd,
113 unsigned char *buf,
114 u32 begrun,
115 u32 runlength)
116{
117 u32 last_r2tsn;
118 struct iscsi_r2t *r2t;
119
120 /*
121 * Make sure the initiator is not requesting retransmission
122 * of R2TSNs already acknowledged by a TMR TASK_REASSIGN.
123 */
124 if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
125 (begrun <= cmd->acked_data_sn)) {
126 pr_err("ITT: 0x%08x, R2T SNACK requesting"
127 " retransmission of R2TSN: 0x%08x to 0x%08x but already"
128 " acked to R2TSN: 0x%08x by TMR TASK_REASSIGN,"
129 " protocol error.\n", cmd->init_task_tag, begrun,
130 (begrun + runlength), cmd->acked_data_sn);
131
132 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
133 }
134
135 if (runlength) {
136 if ((begrun + runlength) > cmd->r2t_sn) {
137 pr_err("Command ITT: 0x%08x received R2T SNACK"
138 " with BegRun: 0x%08x, RunLength: 0x%08x, exceeds"
139 " current R2TSN: 0x%08x, protocol error.\n",
140 cmd->init_task_tag, begrun, runlength, cmd->r2t_sn);
141 return iscsit_reject_cmd(cmd,
142 ISCSI_REASON_BOOKMARK_INVALID, buf);
143 }
144 last_r2tsn = (begrun + runlength);
145 } else
146 last_r2tsn = cmd->r2t_sn;
147
148 while (begrun < last_r2tsn) {
149 r2t = iscsit_get_holder_for_r2tsn(cmd, begrun);
150 if (!r2t)
151 return -1;
152 if (iscsit_send_recovery_r2t_for_snack(cmd, r2t) < 0)
153 return -1;
154
155 begrun++;
156 }
157
158 return 0;
159}
160
161/*
162 * Generates Offsets and NextBurstLength based on Begrun and Runlength
163 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
164 *
165 * For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only.
166 *
167 * FIXME: How is this handled for a RData SNACK?
168 */
169int iscsit_create_recovery_datain_values_datasequenceinorder_yes(
170 struct iscsit_cmd *cmd,
171 struct iscsi_datain_req *dr)
172{
173 u32 data_sn = 0, data_sn_count = 0;
174 u32 pdu_start = 0, seq_no = 0;
175 u32 begrun = dr->begrun;
176 struct iscsit_conn *conn = cmd->conn;
177
178 while (begrun > data_sn++) {
179 data_sn_count++;
180 if ((dr->next_burst_len +
181 conn->conn_ops->MaxRecvDataSegmentLength) <
182 conn->sess->sess_ops->MaxBurstLength) {
183 dr->read_data_done +=
184 conn->conn_ops->MaxRecvDataSegmentLength;
185 dr->next_burst_len +=
186 conn->conn_ops->MaxRecvDataSegmentLength;
187 } else {
188 dr->read_data_done +=
189 (conn->sess->sess_ops->MaxBurstLength -
190 dr->next_burst_len);
191 dr->next_burst_len = 0;
192 pdu_start += data_sn_count;
193 data_sn_count = 0;
194 seq_no++;
195 }
196 }
197
198 if (!conn->sess->sess_ops->DataPDUInOrder) {
199 cmd->seq_no = seq_no;
200 cmd->pdu_start = pdu_start;
201 cmd->pdu_send_order = data_sn_count;
202 }
203
204 return 0;
205}
206
207/*
208 * Generates Offsets and NextBurstLength based on Begrun and Runlength
209 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
210 *
211 * For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only.
212 *
213 * FIXME: How is this handled for a RData SNACK?
214 */
215int iscsit_create_recovery_datain_values_datasequenceinorder_no(
216 struct iscsit_cmd *cmd,
217 struct iscsi_datain_req *dr)
218{
219 int found_seq = 0, i;
220 u32 data_sn, read_data_done = 0, seq_send_order = 0;
221 u32 begrun = dr->begrun;
222 u32 runlength = dr->runlength;
223 struct iscsit_conn *conn = cmd->conn;
224 struct iscsi_seq *first_seq = NULL, *seq = NULL;
225
226 if (!cmd->seq_list) {
227 pr_err("struct iscsit_cmd->seq_list is NULL!\n");
228 return -1;
229 }
230
231 /*
232 * Calculate read_data_done for all sequences containing a
233 * first_datasn and last_datasn less than the BegRun.
234 *
235 * Locate the struct iscsi_seq the BegRun lies within and calculate
236 * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength.
237 *
238 * Also use struct iscsi_seq->seq_send_order to determine where to start.
239 */
240 for (i = 0; i < cmd->seq_count; i++) {
241 seq = &cmd->seq_list[i];
242
243 if (!seq->seq_send_order)
244 first_seq = seq;
245
246 /*
247 * No data has been transferred for this DataIN sequence, so the
248 * seq->first_datasn and seq->last_datasn have not been set.
249 */
250 if (!seq->sent) {
251 pr_err("Ignoring non-sent sequence 0x%08x ->"
252 " 0x%08x\n\n", seq->first_datasn,
253 seq->last_datasn);
254 continue;
255 }
256
257 /*
258 * This DataIN sequence is precedes the received BegRun, add the
259 * total xfer_len of the sequence to read_data_done and reset
260 * seq->pdu_send_order.
261 */
262 if ((seq->first_datasn < begrun) &&
263 (seq->last_datasn < begrun)) {
264 pr_err("Pre BegRun sequence 0x%08x ->"
265 " 0x%08x\n", seq->first_datasn,
266 seq->last_datasn);
267
268 read_data_done += cmd->seq_list[i].xfer_len;
269 seq->next_burst_len = seq->pdu_send_order = 0;
270 continue;
271 }
272
273 /*
274 * The BegRun lies within this DataIN sequence.
275 */
276 if ((seq->first_datasn <= begrun) &&
277 (seq->last_datasn >= begrun)) {
278 pr_err("Found sequence begrun: 0x%08x in"
279 " 0x%08x -> 0x%08x\n", begrun,
280 seq->first_datasn, seq->last_datasn);
281
282 seq_send_order = seq->seq_send_order;
283 data_sn = seq->first_datasn;
284 seq->next_burst_len = seq->pdu_send_order = 0;
285 found_seq = 1;
286
287 /*
288 * For DataPDUInOrder=Yes, while the first DataSN of
289 * the sequence is less than the received BegRun, add
290 * the MaxRecvDataSegmentLength to read_data_done and
291 * to the sequence's next_burst_len;
292 *
293 * For DataPDUInOrder=No, while the first DataSN of the
294 * sequence is less than the received BegRun, find the
295 * struct iscsi_pdu of the DataSN in question and add the
296 * MaxRecvDataSegmentLength to read_data_done and to the
297 * sequence's next_burst_len;
298 */
299 if (conn->sess->sess_ops->DataPDUInOrder) {
300 while (data_sn < begrun) {
301 seq->pdu_send_order++;
302 read_data_done +=
303 conn->conn_ops->MaxRecvDataSegmentLength;
304 seq->next_burst_len +=
305 conn->conn_ops->MaxRecvDataSegmentLength;
306 data_sn++;
307 }
308 } else {
309 int j;
310 struct iscsi_pdu *pdu;
311
312 while (data_sn < begrun) {
313 seq->pdu_send_order++;
314
315 for (j = 0; j < seq->pdu_count; j++) {
316 pdu = &cmd->pdu_list[
317 seq->pdu_start + j];
318 if (pdu->data_sn == data_sn) {
319 read_data_done +=
320 pdu->length;
321 seq->next_burst_len +=
322 pdu->length;
323 }
324 }
325 data_sn++;
326 }
327 }
328 continue;
329 }
330
331 /*
332 * This DataIN sequence is larger than the received BegRun,
333 * reset seq->pdu_send_order and continue.
334 */
335 if ((seq->first_datasn > begrun) ||
336 (seq->last_datasn > begrun)) {
337 pr_err("Post BegRun sequence 0x%08x -> 0x%08x\n",
338 seq->first_datasn, seq->last_datasn);
339
340 seq->next_burst_len = seq->pdu_send_order = 0;
341 continue;
342 }
343 }
344
345 if (!found_seq) {
346 if (!begrun) {
347 if (!first_seq) {
348 pr_err("ITT: 0x%08x, Begrun: 0x%08x"
349 " but first_seq is NULL\n",
350 cmd->init_task_tag, begrun);
351 return -1;
352 }
353 seq_send_order = first_seq->seq_send_order;
354 seq->next_burst_len = seq->pdu_send_order = 0;
355 goto done;
356 }
357
358 pr_err("Unable to locate struct iscsi_seq for ITT: 0x%08x,"
359 " BegRun: 0x%08x, RunLength: 0x%08x while"
360 " DataSequenceInOrder=No and DataPDUInOrder=%s.\n",
361 cmd->init_task_tag, begrun, runlength,
362 (conn->sess->sess_ops->DataPDUInOrder) ? "Yes" : "No");
363 return -1;
364 }
365
366done:
367 dr->read_data_done = read_data_done;
368 dr->seq_send_order = seq_send_order;
369
370 return 0;
371}
372
373static int iscsit_handle_recovery_datain(
374 struct iscsit_cmd *cmd,
375 unsigned char *buf,
376 u32 begrun,
377 u32 runlength)
378{
379 struct iscsit_conn *conn = cmd->conn;
380 struct iscsi_datain_req *dr;
381 struct se_cmd *se_cmd = &cmd->se_cmd;
382
383 if (!(se_cmd->transport_state & CMD_T_COMPLETE)) {
384 pr_err("Ignoring ITT: 0x%08x Data SNACK\n",
385 cmd->init_task_tag);
386 return 0;
387 }
388
389 /*
390 * Make sure the initiator is not requesting retransmission
391 * of DataSNs already acknowledged by a Data ACK SNACK.
392 */
393 if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
394 (begrun <= cmd->acked_data_sn)) {
395 pr_err("ITT: 0x%08x, Data SNACK requesting"
396 " retransmission of DataSN: 0x%08x to 0x%08x but"
397 " already acked to DataSN: 0x%08x by Data ACK SNACK,"
398 " protocol error.\n", cmd->init_task_tag, begrun,
399 (begrun + runlength), cmd->acked_data_sn);
400
401 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
402 }
403
404 /*
405 * Make sure BegRun and RunLength in the Data SNACK are sane.
406 * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent.
407 */
408 if ((begrun + runlength) > (cmd->data_sn - 1)) {
409 pr_err("Initiator requesting BegRun: 0x%08x, RunLength"
410 ": 0x%08x greater than maximum DataSN: 0x%08x.\n",
411 begrun, runlength, (cmd->data_sn - 1));
412 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID,
413 buf);
414 }
415
416 dr = iscsit_allocate_datain_req();
417 if (!dr)
418 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
419 buf);
420
421 dr->data_sn = dr->begrun = begrun;
422 dr->runlength = runlength;
423 dr->generate_recovery_values = 1;
424 dr->recovery = DATAIN_WITHIN_COMMAND_RECOVERY;
425
426 iscsit_attach_datain_req(cmd, dr);
427
428 cmd->i_state = ISTATE_SEND_DATAIN;
429 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
430
431 return 0;
432}
433
434int iscsit_handle_recovery_datain_or_r2t(
435 struct iscsit_conn *conn,
436 unsigned char *buf,
437 itt_t init_task_tag,
438 u32 targ_xfer_tag,
439 u32 begrun,
440 u32 runlength)
441{
442 struct iscsit_cmd *cmd;
443
444 cmd = iscsit_find_cmd_from_itt(conn, init_task_tag);
445 if (!cmd)
446 return 0;
447
448 /*
449 * FIXME: This will not work for bidi commands.
450 */
451 switch (cmd->data_direction) {
452 case DMA_TO_DEVICE:
453 return iscsit_handle_r2t_snack(cmd, buf, begrun, runlength);
454 case DMA_FROM_DEVICE:
455 return iscsit_handle_recovery_datain(cmd, buf, begrun,
456 runlength);
457 default:
458 pr_err("Unknown cmd->data_direction: 0x%02x\n",
459 cmd->data_direction);
460 return -1;
461 }
462
463 return 0;
464}
465
466/* #warning FIXME: Status SNACK needs to be dependent on OPCODE!!! */
467int iscsit_handle_status_snack(
468 struct iscsit_conn *conn,
469 itt_t init_task_tag,
470 u32 targ_xfer_tag,
471 u32 begrun,
472 u32 runlength)
473{
474 struct iscsit_cmd *cmd = NULL;
475 u32 last_statsn;
476 int found_cmd;
477
478 if (!begrun) {
479 begrun = conn->exp_statsn;
480 } else if (conn->exp_statsn > begrun) {
481 pr_err("Got Status SNACK Begrun: 0x%08x, RunLength:"
482 " 0x%08x but already got ExpStatSN: 0x%08x on CID:"
483 " %hu.\n", begrun, runlength, conn->exp_statsn,
484 conn->cid);
485 return 0;
486 }
487
488 last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength);
489
490 while (begrun < last_statsn) {
491 found_cmd = 0;
492
493 spin_lock_bh(lock: &conn->cmd_lock);
494 list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
495 if (cmd->stat_sn == begrun) {
496 found_cmd = 1;
497 break;
498 }
499 }
500 spin_unlock_bh(lock: &conn->cmd_lock);
501
502 if (!found_cmd) {
503 pr_err("Unable to find StatSN: 0x%08x for"
504 " a Status SNACK, assuming this was a"
505 " protactic SNACK for an untransmitted"
506 " StatSN, ignoring.\n", begrun);
507 begrun++;
508 continue;
509 }
510
511 spin_lock_bh(lock: &cmd->istate_lock);
512 if (cmd->i_state == ISTATE_SEND_DATAIN) {
513 spin_unlock_bh(lock: &cmd->istate_lock);
514 pr_err("Ignoring Status SNACK for BegRun:"
515 " 0x%08x, RunLength: 0x%08x, assuming this was"
516 " a protactic SNACK for an untransmitted"
517 " StatSN\n", begrun, runlength);
518 begrun++;
519 continue;
520 }
521 spin_unlock_bh(lock: &cmd->istate_lock);
522
523 cmd->i_state = ISTATE_SEND_STATUS_RECOVERY;
524 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
525 begrun++;
526 }
527
528 return 0;
529}
530
531int iscsit_handle_data_ack(
532 struct iscsit_conn *conn,
533 u32 targ_xfer_tag,
534 u32 begrun,
535 u32 runlength)
536{
537 struct iscsit_cmd *cmd = NULL;
538
539 cmd = iscsit_find_cmd_from_ttt(conn, targ_xfer_tag);
540 if (!cmd) {
541 pr_err("Data ACK SNACK for TTT: 0x%08x is"
542 " invalid.\n", targ_xfer_tag);
543 return -1;
544 }
545
546 if (begrun <= cmd->acked_data_sn) {
547 pr_err("ITT: 0x%08x Data ACK SNACK BegRUN: 0x%08x is"
548 " less than the already acked DataSN: 0x%08x.\n",
549 cmd->init_task_tag, begrun, cmd->acked_data_sn);
550 return -1;
551 }
552
553 /*
554 * For Data ACK SNACK, BegRun is the next expected DataSN.
555 * (see iSCSI v19: 10.16.6)
556 */
557 cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
558 cmd->acked_data_sn = (begrun - 1);
559
560 pr_debug("Received Data ACK SNACK for ITT: 0x%08x,"
561 " updated acked DataSN to 0x%08x.\n",
562 cmd->init_task_tag, cmd->acked_data_sn);
563
564 return 0;
565}
566
567static int iscsit_send_recovery_r2t(
568 struct iscsit_cmd *cmd,
569 u32 offset,
570 u32 xfer_len)
571{
572 int ret;
573
574 spin_lock_bh(lock: &cmd->r2t_lock);
575 ret = iscsit_add_r2t_to_list(cmd, offset, xfer_len, 1, 0);
576 spin_unlock_bh(lock: &cmd->r2t_lock);
577
578 return ret;
579}
580
581int iscsit_dataout_datapduinorder_no_fbit(
582 struct iscsit_cmd *cmd,
583 struct iscsi_pdu *pdu)
584{
585 int i, send_recovery_r2t = 0, recovery = 0;
586 u32 length = 0, offset = 0, pdu_count = 0, xfer_len = 0;
587 struct iscsit_conn *conn = cmd->conn;
588 struct iscsi_pdu *first_pdu = NULL;
589
590 /*
591 * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count
592 * of the DataOUT sequence.
593 */
594 if (conn->sess->sess_ops->DataSequenceInOrder) {
595 for (i = 0; i < cmd->pdu_count; i++) {
596 if (cmd->pdu_list[i].seq_no == pdu->seq_no) {
597 if (!first_pdu)
598 first_pdu = &cmd->pdu_list[i];
599 xfer_len += cmd->pdu_list[i].length;
600 pdu_count++;
601 } else if (pdu_count)
602 break;
603 }
604 } else {
605 struct iscsi_seq *seq = cmd->seq_ptr;
606
607 first_pdu = &cmd->pdu_list[seq->pdu_start];
608 pdu_count = seq->pdu_count;
609 }
610
611 if (!first_pdu || !pdu_count)
612 return DATAOUT_CANNOT_RECOVER;
613
614 /*
615 * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu.
616 * The following ugly logic does batching of not received PDUs.
617 */
618 for (i = 0; i < pdu_count; i++) {
619 if (first_pdu[i].status == ISCSI_PDU_RECEIVED_OK) {
620 if (!send_recovery_r2t)
621 continue;
622
623 if (iscsit_send_recovery_r2t(cmd, offset, xfer_len: length) < 0)
624 return DATAOUT_CANNOT_RECOVER;
625
626 send_recovery_r2t = length = offset = 0;
627 continue;
628 }
629 /*
630 * Set recovery = 1 for any missing, CRC failed, or timed
631 * out PDUs to let the DataOUT logic know that this sequence
632 * has not been completed yet.
633 *
634 * Also, only send a Recovery R2T for ISCSI_PDU_NOT_RECEIVED.
635 * We assume if the PDU either failed CRC or timed out
636 * that a Recovery R2T has already been sent.
637 */
638 recovery = 1;
639
640 if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED)
641 continue;
642
643 if (!offset)
644 offset = first_pdu[i].offset;
645 length += first_pdu[i].length;
646
647 send_recovery_r2t = 1;
648 }
649
650 if (send_recovery_r2t)
651 if (iscsit_send_recovery_r2t(cmd, offset, xfer_len: length) < 0)
652 return DATAOUT_CANNOT_RECOVER;
653
654 return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY;
655}
656
657static int iscsit_recalculate_dataout_values(
658 struct iscsit_cmd *cmd,
659 u32 pdu_offset,
660 u32 pdu_length,
661 u32 *r2t_offset,
662 u32 *r2t_length)
663{
664 int i;
665 struct iscsit_conn *conn = cmd->conn;
666 struct iscsi_pdu *pdu = NULL;
667
668 if (conn->sess->sess_ops->DataSequenceInOrder) {
669 cmd->data_sn = 0;
670
671 if (conn->sess->sess_ops->DataPDUInOrder) {
672 *r2t_offset = cmd->write_data_done;
673 *r2t_length = (cmd->seq_end_offset -
674 cmd->write_data_done);
675 return 0;
676 }
677
678 *r2t_offset = cmd->seq_start_offset;
679 *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset);
680
681 for (i = 0; i < cmd->pdu_count; i++) {
682 pdu = &cmd->pdu_list[i];
683
684 if (pdu->status != ISCSI_PDU_RECEIVED_OK)
685 continue;
686
687 if ((pdu->offset >= cmd->seq_start_offset) &&
688 ((pdu->offset + pdu->length) <=
689 cmd->seq_end_offset)) {
690 if (!cmd->unsolicited_data)
691 cmd->next_burst_len -= pdu->length;
692 else
693 cmd->first_burst_len -= pdu->length;
694
695 cmd->write_data_done -= pdu->length;
696 pdu->status = ISCSI_PDU_NOT_RECEIVED;
697 }
698 }
699 } else {
700 struct iscsi_seq *seq = NULL;
701
702 seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length);
703 if (!seq)
704 return -1;
705
706 *r2t_offset = seq->orig_offset;
707 *r2t_length = seq->xfer_len;
708
709 cmd->write_data_done -= (seq->offset - seq->orig_offset);
710 if (cmd->immediate_data)
711 cmd->first_burst_len = cmd->write_data_done;
712
713 seq->data_sn = 0;
714 seq->offset = seq->orig_offset;
715 seq->next_burst_len = 0;
716 seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY;
717
718 if (conn->sess->sess_ops->DataPDUInOrder)
719 return 0;
720
721 for (i = 0; i < seq->pdu_count; i++) {
722 pdu = &cmd->pdu_list[i+seq->pdu_start];
723
724 if (pdu->status != ISCSI_PDU_RECEIVED_OK)
725 continue;
726
727 pdu->status = ISCSI_PDU_NOT_RECEIVED;
728 }
729 }
730
731 return 0;
732}
733
734int iscsit_recover_dataout_sequence(
735 struct iscsit_cmd *cmd,
736 u32 pdu_offset,
737 u32 pdu_length)
738{
739 u32 r2t_length = 0, r2t_offset = 0;
740
741 spin_lock_bh(lock: &cmd->istate_lock);
742 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
743 spin_unlock_bh(lock: &cmd->istate_lock);
744
745 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
746 r2t_offset: &r2t_offset, r2t_length: &r2t_length) < 0)
747 return DATAOUT_CANNOT_RECOVER;
748
749 iscsit_send_recovery_r2t(cmd, offset: r2t_offset, xfer_len: r2t_length);
750
751 return DATAOUT_WITHIN_COMMAND_RECOVERY;
752}
753
754static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void)
755{
756 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL;
757
758 ooo_cmdsn = kmem_cache_zalloc(k: lio_ooo_cache, GFP_ATOMIC);
759 if (!ooo_cmdsn) {
760 pr_err("Unable to allocate memory for"
761 " struct iscsi_ooo_cmdsn.\n");
762 return NULL;
763 }
764 INIT_LIST_HEAD(list: &ooo_cmdsn->ooo_list);
765
766 return ooo_cmdsn;
767}
768
769static int iscsit_attach_ooo_cmdsn(
770 struct iscsit_session *sess,
771 struct iscsi_ooo_cmdsn *ooo_cmdsn)
772{
773 struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp;
774
775 lockdep_assert_held(&sess->cmdsn_mutex);
776
777 /*
778 * We attach the struct iscsi_ooo_cmdsn entry to the out of order
779 * list in increasing CmdSN order.
780 * This allows iscsi_execute_ooo_cmdsns() to detect any
781 * additional CmdSN holes while performing delayed execution.
782 */
783 if (list_empty(head: &sess->sess_ooo_cmdsn_list))
784 list_add_tail(new: &ooo_cmdsn->ooo_list,
785 head: &sess->sess_ooo_cmdsn_list);
786 else {
787 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
788 typeof(*ooo_tail), ooo_list);
789 /*
790 * CmdSN is greater than the tail of the list.
791 */
792 if (iscsi_sna_lt(n1: ooo_tail->cmdsn, n2: ooo_cmdsn->cmdsn))
793 list_add_tail(new: &ooo_cmdsn->ooo_list,
794 head: &sess->sess_ooo_cmdsn_list);
795 else {
796 /*
797 * CmdSN is either lower than the head, or somewhere
798 * in the middle.
799 */
800 list_for_each_entry(ooo_tmp, &sess->sess_ooo_cmdsn_list,
801 ooo_list) {
802 if (iscsi_sna_lt(n1: ooo_tmp->cmdsn, n2: ooo_cmdsn->cmdsn))
803 continue;
804
805 /* Insert before this entry */
806 list_add(new: &ooo_cmdsn->ooo_list,
807 head: ooo_tmp->ooo_list.prev);
808 break;
809 }
810 }
811 }
812
813 return 0;
814}
815
816/*
817 * Removes an struct iscsi_ooo_cmdsn from a session's list,
818 * called with struct iscsit_session->cmdsn_mutex held.
819 */
820void iscsit_remove_ooo_cmdsn(
821 struct iscsit_session *sess,
822 struct iscsi_ooo_cmdsn *ooo_cmdsn)
823{
824 list_del(entry: &ooo_cmdsn->ooo_list);
825 kmem_cache_free(s: lio_ooo_cache, objp: ooo_cmdsn);
826}
827
828void iscsit_clear_ooo_cmdsns_for_conn(struct iscsit_conn *conn)
829{
830 struct iscsi_ooo_cmdsn *ooo_cmdsn;
831 struct iscsit_session *sess = conn->sess;
832
833 mutex_lock(&sess->cmdsn_mutex);
834 list_for_each_entry(ooo_cmdsn, &sess->sess_ooo_cmdsn_list, ooo_list) {
835 if (ooo_cmdsn->cid != conn->cid)
836 continue;
837
838 ooo_cmdsn->cmd = NULL;
839 }
840 mutex_unlock(lock: &sess->cmdsn_mutex);
841}
842
843int iscsit_execute_ooo_cmdsns(struct iscsit_session *sess)
844{
845 int ooo_count = 0;
846 struct iscsit_cmd *cmd = NULL;
847 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
848
849 lockdep_assert_held(&sess->cmdsn_mutex);
850
851 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
852 &sess->sess_ooo_cmdsn_list, ooo_list) {
853 if (ooo_cmdsn->cmdsn != sess->exp_cmd_sn)
854 continue;
855
856 if (!ooo_cmdsn->cmd) {
857 sess->exp_cmd_sn++;
858 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
859 continue;
860 }
861
862 cmd = ooo_cmdsn->cmd;
863 cmd->i_state = cmd->deferred_i_state;
864 ooo_count++;
865 sess->exp_cmd_sn++;
866 pr_debug("Executing out of order CmdSN: 0x%08x,"
867 " incremented ExpCmdSN to 0x%08x.\n",
868 cmd->cmd_sn, sess->exp_cmd_sn);
869
870 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
871
872 if (iscsit_execute_cmd(cmd, 1) < 0)
873 return -1;
874 }
875
876 return ooo_count;
877}
878
879/*
880 * Called either:
881 *
882 * 1. With sess->cmdsn_mutex held from iscsi_execute_ooo_cmdsns()
883 * or iscsi_check_received_cmdsn().
884 * 2. With no locks held directly from iscsi_handle_XXX_pdu() functions
885 * for immediate commands.
886 */
887int iscsit_execute_cmd(struct iscsit_cmd *cmd, int ooo)
888{
889 struct se_cmd *se_cmd = &cmd->se_cmd;
890 struct iscsit_conn *conn = cmd->conn;
891 int lr = 0;
892
893 spin_lock_bh(lock: &cmd->istate_lock);
894 if (ooo)
895 cmd->cmd_flags &= ~ICF_OOO_CMDSN;
896
897 switch (cmd->iscsi_opcode) {
898 case ISCSI_OP_SCSI_CMD:
899 /*
900 * Go ahead and send the CHECK_CONDITION status for
901 * any SCSI CDB exceptions that may have occurred.
902 */
903 if (cmd->sense_reason) {
904 if (cmd->sense_reason == TCM_RESERVATION_CONFLICT) {
905 cmd->i_state = ISTATE_SEND_STATUS;
906 spin_unlock_bh(lock: &cmd->istate_lock);
907 iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
908 cmd->i_state);
909 return 0;
910 }
911 spin_unlock_bh(lock: &cmd->istate_lock);
912 if (cmd->se_cmd.transport_state & CMD_T_ABORTED)
913 return 0;
914 return transport_send_check_condition_and_sense(se_cmd,
915 cmd->sense_reason, 0);
916 }
917 /*
918 * Special case for delayed CmdSN with Immediate
919 * Data and/or Unsolicited Data Out attached.
920 */
921 if (cmd->immediate_data) {
922 if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
923 spin_unlock_bh(lock: &cmd->istate_lock);
924 target_execute_cmd(cmd: &cmd->se_cmd);
925 return 0;
926 }
927 spin_unlock_bh(lock: &cmd->istate_lock);
928
929 if (!(cmd->cmd_flags &
930 ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
931 if (cmd->se_cmd.transport_state & CMD_T_ABORTED)
932 return 0;
933
934 iscsit_set_dataout_sequence_values(cmd);
935 conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
936 }
937 return 0;
938 }
939 /*
940 * The default handler.
941 */
942 spin_unlock_bh(lock: &cmd->istate_lock);
943
944 if ((cmd->data_direction == DMA_TO_DEVICE) &&
945 !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
946 if (cmd->se_cmd.transport_state & CMD_T_ABORTED)
947 return 0;
948
949 iscsit_set_unsolicited_dataout(cmd);
950 }
951 return target_submit(se_cmd: &cmd->se_cmd);
952
953 case ISCSI_OP_NOOP_OUT:
954 case ISCSI_OP_TEXT:
955 spin_unlock_bh(lock: &cmd->istate_lock);
956 iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
957 break;
958 case ISCSI_OP_SCSI_TMFUNC:
959 if (cmd->se_cmd.se_tmr_req->response) {
960 spin_unlock_bh(lock: &cmd->istate_lock);
961 iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
962 cmd->i_state);
963 return 0;
964 }
965 spin_unlock_bh(lock: &cmd->istate_lock);
966
967 return transport_generic_handle_tmr(&cmd->se_cmd);
968 case ISCSI_OP_LOGOUT:
969 spin_unlock_bh(lock: &cmd->istate_lock);
970 switch (cmd->logout_reason) {
971 case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
972 lr = iscsit_logout_closesession(cmd, cmd->conn);
973 break;
974 case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
975 lr = iscsit_logout_closeconnection(cmd, cmd->conn);
976 break;
977 case ISCSI_LOGOUT_REASON_RECOVERY:
978 lr = iscsit_logout_removeconnforrecovery(cmd, cmd->conn);
979 break;
980 default:
981 pr_err("Unknown iSCSI Logout Request Code:"
982 " 0x%02x\n", cmd->logout_reason);
983 return -1;
984 }
985
986 return lr;
987 default:
988 spin_unlock_bh(lock: &cmd->istate_lock);
989 pr_err("Cannot perform out of order execution for"
990 " unknown iSCSI Opcode: 0x%02x\n", cmd->iscsi_opcode);
991 return -1;
992 }
993
994 return 0;
995}
996
997void iscsit_free_all_ooo_cmdsns(struct iscsit_session *sess)
998{
999 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
1000
1001 mutex_lock(&sess->cmdsn_mutex);
1002 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
1003 &sess->sess_ooo_cmdsn_list, ooo_list) {
1004
1005 list_del(entry: &ooo_cmdsn->ooo_list);
1006 kmem_cache_free(s: lio_ooo_cache, objp: ooo_cmdsn);
1007 }
1008 mutex_unlock(lock: &sess->cmdsn_mutex);
1009}
1010
1011int iscsit_handle_ooo_cmdsn(
1012 struct iscsit_session *sess,
1013 struct iscsit_cmd *cmd,
1014 u32 cmdsn)
1015{
1016 int batch = 0;
1017 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL;
1018
1019 cmd->deferred_i_state = cmd->i_state;
1020 cmd->i_state = ISTATE_DEFERRED_CMD;
1021 cmd->cmd_flags |= ICF_OOO_CMDSN;
1022
1023 if (list_empty(head: &sess->sess_ooo_cmdsn_list))
1024 batch = 1;
1025 else {
1026 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
1027 typeof(*ooo_tail), ooo_list);
1028 if (ooo_tail->cmdsn != (cmdsn - 1))
1029 batch = 1;
1030 }
1031
1032 ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
1033 if (!ooo_cmdsn)
1034 return -ENOMEM;
1035
1036 ooo_cmdsn->cmd = cmd;
1037 ooo_cmdsn->batch_count = (batch) ?
1038 (cmdsn - sess->exp_cmd_sn) : 1;
1039 ooo_cmdsn->cid = cmd->conn->cid;
1040 ooo_cmdsn->exp_cmdsn = sess->exp_cmd_sn;
1041 ooo_cmdsn->cmdsn = cmdsn;
1042
1043 if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
1044 kmem_cache_free(s: lio_ooo_cache, objp: ooo_cmdsn);
1045 return -ENOMEM;
1046 }
1047
1048 return 0;
1049}
1050
1051static int iscsit_set_dataout_timeout_values(
1052 struct iscsit_cmd *cmd,
1053 u32 *offset,
1054 u32 *length)
1055{
1056 struct iscsit_conn *conn = cmd->conn;
1057 struct iscsi_r2t *r2t;
1058
1059 if (cmd->unsolicited_data) {
1060 *offset = 0;
1061 *length = (conn->sess->sess_ops->FirstBurstLength >
1062 cmd->se_cmd.data_length) ?
1063 cmd->se_cmd.data_length :
1064 conn->sess->sess_ops->FirstBurstLength;
1065 return 0;
1066 }
1067
1068 spin_lock_bh(lock: &cmd->r2t_lock);
1069 if (list_empty(head: &cmd->cmd_r2t_list)) {
1070 pr_err("cmd->cmd_r2t_list is empty!\n");
1071 spin_unlock_bh(lock: &cmd->r2t_lock);
1072 return -1;
1073 }
1074
1075 list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
1076 if (r2t->sent_r2t && !r2t->recovery_r2t && !r2t->seq_complete) {
1077 *offset = r2t->offset;
1078 *length = r2t->xfer_len;
1079 spin_unlock_bh(lock: &cmd->r2t_lock);
1080 return 0;
1081 }
1082 }
1083 spin_unlock_bh(lock: &cmd->r2t_lock);
1084
1085 pr_err("Unable to locate any incomplete DataOUT"
1086 " sequences for ITT: 0x%08x.\n", cmd->init_task_tag);
1087
1088 return -1;
1089}
1090
1091/*
1092 * NOTE: Called from interrupt (timer) context.
1093 */
1094void iscsit_handle_dataout_timeout(struct timer_list *t)
1095{
1096 u32 pdu_length = 0, pdu_offset = 0;
1097 u32 r2t_length = 0, r2t_offset = 0;
1098 struct iscsit_cmd *cmd = from_timer(cmd, t, dataout_timer);
1099 struct iscsit_conn *conn = cmd->conn;
1100 struct iscsit_session *sess = NULL;
1101 struct iscsi_node_attrib *na;
1102
1103 iscsit_inc_conn_usage_count(conn);
1104
1105 spin_lock_bh(lock: &cmd->dataout_timeout_lock);
1106 if (cmd->dataout_timer_flags & ISCSI_TF_STOP) {
1107 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1108 iscsit_dec_conn_usage_count(conn);
1109 return;
1110 }
1111 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1112 sess = conn->sess;
1113 na = iscsit_tpg_get_node_attrib(sess);
1114
1115 if (!sess->sess_ops->ErrorRecoveryLevel) {
1116 pr_err("Unable to recover from DataOut timeout while"
1117 " in ERL=0, closing iSCSI connection for I_T Nexus"
1118 " %s,i,0x%6phN,%s,t,0x%02x\n",
1119 sess->sess_ops->InitiatorName, sess->isid,
1120 sess->tpg->tpg_tiqn->tiqn, (u32)sess->tpg->tpgt);
1121 goto failure;
1122 }
1123
1124 if (++cmd->dataout_timeout_retries == na->dataout_timeout_retries) {
1125 pr_err("Command ITT: 0x%08x exceeded max retries"
1126 " for DataOUT timeout %u, closing iSCSI connection for"
1127 " I_T Nexus %s,i,0x%6phN,%s,t,0x%02x\n",
1128 cmd->init_task_tag, na->dataout_timeout_retries,
1129 sess->sess_ops->InitiatorName, sess->isid,
1130 sess->tpg->tpg_tiqn->tiqn, (u32)sess->tpg->tpgt);
1131 goto failure;
1132 }
1133
1134 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
1135
1136 if (conn->sess->sess_ops->DataSequenceInOrder) {
1137 if (conn->sess->sess_ops->DataPDUInOrder) {
1138 pdu_offset = cmd->write_data_done;
1139 if ((pdu_offset + (conn->sess->sess_ops->MaxBurstLength -
1140 cmd->next_burst_len)) > cmd->se_cmd.data_length)
1141 pdu_length = (cmd->se_cmd.data_length -
1142 cmd->write_data_done);
1143 else
1144 pdu_length = (conn->sess->sess_ops->MaxBurstLength -
1145 cmd->next_burst_len);
1146 } else {
1147 pdu_offset = cmd->seq_start_offset;
1148 pdu_length = (cmd->seq_end_offset -
1149 cmd->seq_start_offset);
1150 }
1151 } else {
1152 if (iscsit_set_dataout_timeout_values(cmd, offset: &pdu_offset,
1153 length: &pdu_length) < 0)
1154 goto failure;
1155 }
1156
1157 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
1158 r2t_offset: &r2t_offset, r2t_length: &r2t_length) < 0)
1159 goto failure;
1160
1161 pr_debug("Command ITT: 0x%08x timed out waiting for"
1162 " completion of %sDataOUT Sequence Offset: %u, Length: %u\n",
1163 cmd->init_task_tag, (cmd->unsolicited_data) ? "Unsolicited " :
1164 "", r2t_offset, r2t_length);
1165
1166 if (iscsit_send_recovery_r2t(cmd, offset: r2t_offset, xfer_len: r2t_length) < 0)
1167 goto failure;
1168
1169 iscsit_start_dataout_timer(cmd, conn);
1170 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1171 iscsit_dec_conn_usage_count(conn);
1172
1173 return;
1174
1175failure:
1176 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1177 iscsit_fill_cxn_timeout_err_stats(sess);
1178 iscsit_cause_connection_reinstatement(conn, 0);
1179 iscsit_dec_conn_usage_count(conn);
1180}
1181
1182void iscsit_mod_dataout_timer(struct iscsit_cmd *cmd)
1183{
1184 struct iscsit_conn *conn = cmd->conn;
1185 struct iscsit_session *sess = conn->sess;
1186 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1187
1188 spin_lock_bh(lock: &cmd->dataout_timeout_lock);
1189 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1190 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1191 return;
1192 }
1193
1194 mod_timer(timer: &cmd->dataout_timer,
1195 expires: (get_jiffies_64() + na->dataout_timeout * HZ));
1196 pr_debug("Updated DataOUT timer for ITT: 0x%08x",
1197 cmd->init_task_tag);
1198 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1199}
1200
1201void iscsit_start_dataout_timer(
1202 struct iscsit_cmd *cmd,
1203 struct iscsit_conn *conn)
1204{
1205 struct iscsit_session *sess = conn->sess;
1206 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1207
1208 lockdep_assert_held(&cmd->dataout_timeout_lock);
1209
1210 if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING)
1211 return;
1212
1213 pr_debug("Starting DataOUT timer for ITT: 0x%08x on"
1214 " CID: %hu.\n", cmd->init_task_tag, conn->cid);
1215
1216 cmd->dataout_timer_flags &= ~ISCSI_TF_STOP;
1217 cmd->dataout_timer_flags |= ISCSI_TF_RUNNING;
1218 mod_timer(timer: &cmd->dataout_timer, expires: jiffies + na->dataout_timeout * HZ);
1219}
1220
1221void iscsit_stop_dataout_timer(struct iscsit_cmd *cmd)
1222{
1223 spin_lock_bh(lock: &cmd->dataout_timeout_lock);
1224 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1225 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1226 return;
1227 }
1228 cmd->dataout_timer_flags |= ISCSI_TF_STOP;
1229 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1230
1231 del_timer_sync(timer: &cmd->dataout_timer);
1232
1233 spin_lock_bh(lock: &cmd->dataout_timeout_lock);
1234 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1235 pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n",
1236 cmd->init_task_tag);
1237 spin_unlock_bh(lock: &cmd->dataout_timeout_lock);
1238}
1239EXPORT_SYMBOL(iscsit_stop_dataout_timer);
1240

source code of linux/drivers/target/iscsi/iscsi_target_erl1.c