Merge branch 'r6040-next'
[linux/fpc-iii.git] / drivers / target / iscsi / iscsi_target_erl1.c
blob9214c9dafa2be56082b792eaccd31ca87420b59e
1 /*******************************************************************************
2 * This file contains error recovery level one used by the iSCSI Target driver.
4 * (c) Copyright 2007-2013 Datera, Inc.
6 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
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.
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 ******************************************************************************/
19 #include <linux/list.h>
20 #include <scsi/iscsi_proto.h>
21 #include <target/target_core_base.h>
22 #include <target/target_core_fabric.h>
23 #include <target/iscsi/iscsi_transport.h>
25 #include <target/iscsi/iscsi_target_core.h>
26 #include "iscsi_target_seq_pdu_list.h"
27 #include "iscsi_target_datain_values.h"
28 #include "iscsi_target_device.h"
29 #include "iscsi_target_tpg.h"
30 #include "iscsi_target_util.h"
31 #include "iscsi_target_erl0.h"
32 #include "iscsi_target_erl1.h"
33 #include "iscsi_target_erl2.h"
34 #include "iscsi_target.h"
36 #define OFFLOAD_BUF_SIZE 32768
39 * Used to dump excess datain payload for certain error recovery
40 * situations. Receive in OFFLOAD_BUF_SIZE max of datain per rx_data().
42 * dump_padding_digest denotes if padding and data digests need
43 * to be dumped.
45 int iscsit_dump_data_payload(
46 struct iscsi_conn *conn,
47 u32 buf_len,
48 int dump_padding_digest)
50 char *buf, pad_bytes[4];
51 int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got;
52 u32 length, padding, offset = 0, size;
53 struct kvec iov;
55 if (conn->sess->sess_ops->RDMAExtensions)
56 return 0;
58 length = (buf_len > OFFLOAD_BUF_SIZE) ? OFFLOAD_BUF_SIZE : buf_len;
60 buf = kzalloc(length, GFP_ATOMIC);
61 if (!buf) {
62 pr_err("Unable to allocate %u bytes for offload"
63 " buffer.\n", length);
64 return -1;
66 memset(&iov, 0, sizeof(struct kvec));
68 while (offset < buf_len) {
69 size = ((offset + length) > buf_len) ?
70 (buf_len - offset) : length;
72 iov.iov_len = size;
73 iov.iov_base = buf;
75 rx_got = rx_data(conn, &iov, 1, size);
76 if (rx_got != size) {
77 ret = DATAOUT_CANNOT_RECOVER;
78 goto out;
81 offset += size;
84 if (!dump_padding_digest)
85 goto out;
87 padding = ((-buf_len) & 3);
88 if (padding != 0) {
89 iov.iov_len = padding;
90 iov.iov_base = pad_bytes;
92 rx_got = rx_data(conn, &iov, 1, padding);
93 if (rx_got != padding) {
94 ret = DATAOUT_CANNOT_RECOVER;
95 goto out;
99 if (conn->conn_ops->DataDigest) {
100 u32 data_crc;
102 iov.iov_len = ISCSI_CRC_LEN;
103 iov.iov_base = &data_crc;
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;
112 out:
113 kfree(buf);
114 return ret;
118 * Used for retransmitting R2Ts from a R2T SNACK request.
120 static int iscsit_send_recovery_r2t_for_snack(
121 struct iscsi_cmd *cmd,
122 struct iscsi_r2t *r2t)
125 * If the struct iscsi_r2t has not been sent yet, we can safely
126 * ignore retransmission
127 * of the R2TSN in question.
129 spin_lock_bh(&cmd->r2t_lock);
130 if (!r2t->sent_r2t) {
131 spin_unlock_bh(&cmd->r2t_lock);
132 return 0;
134 r2t->sent_r2t = 0;
135 spin_unlock_bh(&cmd->r2t_lock);
137 iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
139 return 0;
142 static int iscsit_handle_r2t_snack(
143 struct iscsi_cmd *cmd,
144 unsigned char *buf,
145 u32 begrun,
146 u32 runlength)
148 u32 last_r2tsn;
149 struct iscsi_r2t *r2t;
152 * Make sure the initiator is not requesting retransmission
153 * of R2TSNs already acknowledged by a TMR TASK_REASSIGN.
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);
163 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
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);
175 last_r2tsn = (begrun + runlength);
176 } else
177 last_r2tsn = cmd->r2t_sn;
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;
186 begrun++;
189 return 0;
193 * Generates Offsets and NextBurstLength based on Begrun and Runlength
194 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
196 * For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only.
198 * FIXME: How is this handled for a RData SNACK?
200 int iscsit_create_recovery_datain_values_datasequenceinorder_yes(
201 struct iscsi_cmd *cmd,
202 struct iscsi_datain_req *dr)
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;
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++;
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;
235 return 0;
239 * Generates Offsets and NextBurstLength based on Begrun and Runlength
240 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
242 * For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only.
244 * FIXME: How is this handled for a RData SNACK?
246 int iscsit_create_recovery_datain_values_datasequenceinorder_no(
247 struct iscsi_cmd *cmd,
248 struct iscsi_datain_req *dr)
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;
257 if (!cmd->seq_list) {
258 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
259 return -1;
263 * Calculate read_data_done for all sequences containing a
264 * first_datasn and last_datasn less than the BegRun.
266 * Locate the struct iscsi_seq the BegRun lies within and calculate
267 * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength.
269 * Also use struct iscsi_seq->seq_send_order to determine where to start.
271 for (i = 0; i < cmd->seq_count; i++) {
272 seq = &cmd->seq_list[i];
274 if (!seq->seq_send_order)
275 first_seq = seq;
278 * No data has been transferred for this DataIN sequence, so the
279 * seq->first_datasn and seq->last_datasn have not been set.
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;
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.
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);
299 read_data_done += cmd->seq_list[i].xfer_len;
300 seq->next_burst_len = seq->pdu_send_order = 0;
301 continue;
305 * The BegRun lies within this DataIN sequence.
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);
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;
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;
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;
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++;
339 } else {
340 int j;
341 struct iscsi_pdu *pdu;
343 while (data_sn < begrun) {
344 seq->pdu_send_order++;
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;
356 data_sn++;
359 continue;
363 * This DataIN sequence is larger than the received BegRun,
364 * reset seq->pdu_send_order and continue.
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);
371 seq->next_burst_len = seq->pdu_send_order = 0;
372 continue;
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;
384 seq_send_order = first_seq->seq_send_order;
385 seq->next_burst_len = seq->pdu_send_order = 0;
386 goto done;
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;
397 done:
398 dr->read_data_done = read_data_done;
399 dr->seq_send_order = seq_send_order;
401 return 0;
404 static int iscsit_handle_recovery_datain(
405 struct iscsi_cmd *cmd,
406 unsigned char *buf,
407 u32 begrun,
408 u32 runlength)
410 struct iscsi_conn *conn = cmd->conn;
411 struct iscsi_datain_req *dr;
412 struct se_cmd *se_cmd = &cmd->se_cmd;
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;
421 * Make sure the initiator is not requesting retransmission
422 * of DataSNs already acknowledged by a Data ACK SNACK.
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);
432 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
436 * Make sure BegRun and RunLength in the Data SNACK are sane.
437 * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent.
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);
447 dr = iscsit_allocate_datain_req();
448 if (!dr)
449 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
450 buf);
452 dr->data_sn = dr->begrun = begrun;
453 dr->runlength = runlength;
454 dr->generate_recovery_values = 1;
455 dr->recovery = DATAIN_WITHIN_COMMAND_RECOVERY;
457 iscsit_attach_datain_req(cmd, dr);
459 cmd->i_state = ISTATE_SEND_DATAIN;
460 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
462 return 0;
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)
473 struct iscsi_cmd *cmd;
475 cmd = iscsit_find_cmd_from_itt(conn, init_task_tag);
476 if (!cmd)
477 return 0;
480 * FIXME: This will not work for bidi commands.
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;
494 return 0;
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)
505 struct iscsi_cmd *cmd = NULL;
506 u32 last_statsn;
507 int found_cmd;
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;
519 last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength);
521 while (begrun < last_statsn) {
522 found_cmd = 0;
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;
531 spin_unlock_bh(&conn->cmd_lock);
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;
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;
552 spin_unlock_bh(&cmd->istate_lock);
554 cmd->i_state = ISTATE_SEND_STATUS_RECOVERY;
555 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
556 begrun++;
559 return 0;
562 int iscsit_handle_data_ack(
563 struct iscsi_conn *conn,
564 u32 targ_xfer_tag,
565 u32 begrun,
566 u32 runlength)
568 struct iscsi_cmd *cmd = NULL;
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;
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;
585 * For Data ACK SNACK, BegRun is the next expected DataSN.
586 * (see iSCSI v19: 10.16.6)
588 cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
589 cmd->acked_data_sn = (begrun - 1);
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);
595 return 0;
598 static int iscsit_send_recovery_r2t(
599 struct iscsi_cmd *cmd,
600 u32 offset,
601 u32 xfer_len)
603 int ret;
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);
609 return ret;
612 int iscsit_dataout_datapduinorder_no_fbit(
613 struct iscsi_cmd *cmd,
614 struct iscsi_pdu *pdu)
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;
622 * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count
623 * of the DataOUT sequence.
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;
635 } else {
636 struct iscsi_seq *seq = cmd->seq_ptr;
638 first_pdu = &cmd->pdu_list[seq->pdu_start];
639 pdu_count = seq->pdu_count;
642 if (!first_pdu || !pdu_count)
643 return DATAOUT_CANNOT_RECOVER;
646 * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu.
647 * The following ugly logic does batching of not received PDUs.
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;
654 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
655 return DATAOUT_CANNOT_RECOVER;
657 send_recovery_r2t = length = offset = 0;
658 continue;
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.
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.
669 recovery = 1;
671 if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED)
672 continue;
674 if (!offset)
675 offset = first_pdu[i].offset;
676 length += first_pdu[i].length;
678 send_recovery_r2t = 1;
681 if (send_recovery_r2t)
682 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
683 return DATAOUT_CANNOT_RECOVER;
685 return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY;
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)
695 int i;
696 struct iscsi_conn *conn = cmd->conn;
697 struct iscsi_pdu *pdu = NULL;
699 if (conn->sess->sess_ops->DataSequenceInOrder) {
700 cmd->data_sn = 0;
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;
709 *r2t_offset = cmd->seq_start_offset;
710 *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset);
712 for (i = 0; i < cmd->pdu_count; i++) {
713 pdu = &cmd->pdu_list[i];
715 if (pdu->status != ISCSI_PDU_RECEIVED_OK)
716 continue;
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;
726 cmd->write_data_done -= pdu->length;
727 pdu->status = ISCSI_PDU_NOT_RECEIVED;
730 } else {
731 struct iscsi_seq *seq = NULL;
733 seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length);
734 if (!seq)
735 return -1;
737 *r2t_offset = seq->orig_offset;
738 *r2t_length = seq->xfer_len;
740 cmd->write_data_done -= (seq->offset - seq->orig_offset);
741 if (cmd->immediate_data)
742 cmd->first_burst_len = cmd->write_data_done;
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;
749 if (conn->sess->sess_ops->DataPDUInOrder)
750 return 0;
752 for (i = 0; i < seq->pdu_count; i++) {
753 pdu = &cmd->pdu_list[i+seq->pdu_start];
755 if (pdu->status != ISCSI_PDU_RECEIVED_OK)
756 continue;
758 pdu->status = ISCSI_PDU_NOT_RECEIVED;
762 return 0;
765 int iscsit_recover_dataout_sequence(
766 struct iscsi_cmd *cmd,
767 u32 pdu_offset,
768 u32 pdu_length)
770 u32 r2t_length = 0, r2t_offset = 0;
772 spin_lock_bh(&cmd->istate_lock);
773 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
774 spin_unlock_bh(&cmd->istate_lock);
776 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
777 &r2t_offset, &r2t_length) < 0)
778 return DATAOUT_CANNOT_RECOVER;
780 iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length);
782 return DATAOUT_WITHIN_COMMAND_RECOVERY;
785 static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void)
787 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL;
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;
795 INIT_LIST_HEAD(&ooo_cmdsn->ooo_list);
797 return ooo_cmdsn;
801 * Called with sess->cmdsn_mutex held.
803 static int iscsit_attach_ooo_cmdsn(
804 struct iscsi_session *sess,
805 struct iscsi_ooo_cmdsn *ooo_cmdsn)
807 struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp;
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.
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);
821 * CmdSN is greater than the tail of the list.
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 {
828 * CmdSN is either lower than the head, or somewhere
829 * in the middle.
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;
836 /* Insert before this entry */
837 list_add(&ooo_cmdsn->ooo_list,
838 ooo_tmp->ooo_list.prev);
839 break;
844 return 0;
848 * Removes an struct iscsi_ooo_cmdsn from a session's list,
849 * called with struct iscsi_session->cmdsn_mutex held.
851 void iscsit_remove_ooo_cmdsn(
852 struct iscsi_session *sess,
853 struct iscsi_ooo_cmdsn *ooo_cmdsn)
855 list_del(&ooo_cmdsn->ooo_list);
856 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
859 void iscsit_clear_ooo_cmdsns_for_conn(struct iscsi_conn *conn)
861 struct iscsi_ooo_cmdsn *ooo_cmdsn;
862 struct iscsi_session *sess = conn->sess;
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;
869 ooo_cmdsn->cmd = NULL;
871 mutex_unlock(&sess->cmdsn_mutex);
875 * Called with sess->cmdsn_mutex held.
877 int iscsit_execute_ooo_cmdsns(struct iscsi_session *sess)
879 int ooo_count = 0;
880 struct iscsi_cmd *cmd = NULL;
881 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
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;
888 if (!ooo_cmdsn->cmd) {
889 sess->exp_cmd_sn++;
890 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
891 continue;
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);
902 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
904 if (iscsit_execute_cmd(cmd, 1) < 0)
905 return -1;
907 continue;
910 return ooo_count;
914 * Called either:
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.
921 int iscsit_execute_cmd(struct iscsi_cmd *cmd, int ooo)
923 struct se_cmd *se_cmd = &cmd->se_cmd;
924 struct iscsi_conn *conn = cmd->conn;
925 int lr = 0;
927 spin_lock_bh(&cmd->istate_lock);
928 if (ooo)
929 cmd->cmd_flags &= ~ICF_OOO_CMDSN;
931 switch (cmd->iscsi_opcode) {
932 case ISCSI_OP_SCSI_CMD:
934 * Go ahead and send the CHECK_CONDITION status for
935 * any SCSI CDB exceptions that may have occurred.
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;
945 spin_unlock_bh(&cmd->istate_lock);
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()
953 if (transport_check_aborted_status(se_cmd,
954 (cmd->unsolicited_data == 0)) != 0)
955 return 0;
957 * Otherwise send CHECK_CONDITION and sense for
958 * exception
960 return transport_send_check_condition_and_sense(se_cmd,
961 cmd->sense_reason, 0);
964 * Special case for delayed CmdSN with Immediate
965 * Data and/or Unsolicited Data Out attached.
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;
973 spin_unlock_bh(&cmd->istate_lock);
975 if (!(cmd->cmd_flags &
976 ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
978 * Send the delayed TASK_ABORTED status for
979 * WRITEs if no more unsolicitied data is
980 * expected.
982 if (transport_check_aborted_status(se_cmd, 1)
983 != 0)
984 return 0;
986 iscsit_set_dataout_sequence_values(cmd);
987 conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
989 return 0;
992 * The default handler.
994 spin_unlock_bh(&cmd->istate_lock);
996 if ((cmd->data_direction == DMA_TO_DEVICE) &&
997 !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
999 * Send the delayed TASK_ABORTED status for WRITEs if
1000 * no more nsolicitied data is expected.
1002 if (transport_check_aborted_status(se_cmd, 1) != 0)
1003 return 0;
1005 iscsit_set_unsoliticed_dataout(cmd);
1007 return transport_handle_cdb_direct(&cmd->se_cmd);
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;
1021 spin_unlock_bh(&cmd->istate_lock);
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;
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;
1050 return 0;
1053 void iscsit_free_all_ooo_cmdsns(struct iscsi_session *sess)
1055 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
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) {
1061 list_del(&ooo_cmdsn->ooo_list);
1062 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1064 mutex_unlock(&sess->cmdsn_mutex);
1067 int iscsit_handle_ooo_cmdsn(
1068 struct iscsi_session *sess,
1069 struct iscsi_cmd *cmd,
1070 u32 cmdsn)
1072 int batch = 0;
1073 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL;
1075 cmd->deferred_i_state = cmd->i_state;
1076 cmd->i_state = ISTATE_DEFERRED_CMD;
1077 cmd->cmd_flags |= ICF_OOO_CMDSN;
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;
1088 ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
1089 if (!ooo_cmdsn)
1090 return -ENOMEM;
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;
1099 if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
1100 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1101 return -ENOMEM;
1104 return 0;
1107 static int iscsit_set_dataout_timeout_values(
1108 struct iscsi_cmd *cmd,
1109 u32 *offset,
1110 u32 *length)
1112 struct iscsi_conn *conn = cmd->conn;
1113 struct iscsi_r2t *r2t;
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;
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;
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;
1139 spin_unlock_bh(&cmd->r2t_lock);
1141 pr_err("Unable to locate any incomplete DataOUT"
1142 " sequences for ITT: 0x%08x.\n", cmd->init_task_tag);
1144 return -1;
1148 * NOTE: Called from interrupt (timer) context.
1150 static void iscsit_handle_dataout_timeout(unsigned long data)
1152 u32 pdu_length = 0, pdu_offset = 0;
1153 u32 r2t_length = 0, r2t_offset = 0;
1154 struct iscsi_cmd *cmd = (struct iscsi_cmd *) data;
1155 struct iscsi_conn *conn = cmd->conn;
1156 struct iscsi_session *sess = NULL;
1157 struct iscsi_node_attrib *na;
1159 iscsit_inc_conn_usage_count(conn);
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;
1167 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1168 sess = conn->sess;
1169 na = iscsit_tpg_get_node_attrib(sess);
1171 if (!sess->sess_ops->ErrorRecoveryLevel) {
1172 pr_debug("Unable to recover from DataOut timeout while"
1173 " in ERL=0.\n");
1174 goto failure;
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;
1184 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
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);
1201 } else {
1202 if (iscsit_set_dataout_timeout_values(cmd, &pdu_offset,
1203 &pdu_length) < 0)
1204 goto failure;
1207 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
1208 &r2t_offset, &r2t_length) < 0)
1209 goto failure;
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);
1216 if (iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length) < 0)
1217 goto failure;
1219 iscsit_start_dataout_timer(cmd, conn);
1220 spin_unlock_bh(&cmd->dataout_timeout_lock);
1221 iscsit_dec_conn_usage_count(conn);
1223 return;
1225 failure:
1226 spin_unlock_bh(&cmd->dataout_timeout_lock);
1227 iscsit_cause_connection_reinstatement(conn, 0);
1228 iscsit_dec_conn_usage_count(conn);
1231 void iscsit_mod_dataout_timer(struct iscsi_cmd *cmd)
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);
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;
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);
1251 * Called with cmd->dataout_timeout_lock held.
1253 void iscsit_start_dataout_timer(
1254 struct iscsi_cmd *cmd,
1255 struct iscsi_conn *conn)
1257 struct iscsi_session *sess = conn->sess;
1258 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1260 if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING)
1261 return;
1263 pr_debug("Starting DataOUT timer for ITT: 0x%08x on"
1264 " CID: %hu.\n", cmd->init_task_tag, conn->cid);
1266 init_timer(&cmd->dataout_timer);
1267 cmd->dataout_timer.expires = (get_jiffies_64() + na->dataout_timeout * HZ);
1268 cmd->dataout_timer.data = (unsigned long)cmd;
1269 cmd->dataout_timer.function = iscsit_handle_dataout_timeout;
1270 cmd->dataout_timer_flags &= ~ISCSI_TF_STOP;
1271 cmd->dataout_timer_flags |= ISCSI_TF_RUNNING;
1272 add_timer(&cmd->dataout_timer);
1275 void iscsit_stop_dataout_timer(struct iscsi_cmd *cmd)
1277 spin_lock_bh(&cmd->dataout_timeout_lock);
1278 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1279 spin_unlock_bh(&cmd->dataout_timeout_lock);
1280 return;
1282 cmd->dataout_timer_flags |= ISCSI_TF_STOP;
1283 spin_unlock_bh(&cmd->dataout_timeout_lock);
1285 del_timer_sync(&cmd->dataout_timer);
1287 spin_lock_bh(&cmd->dataout_timeout_lock);
1288 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1289 pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n",
1290 cmd->init_task_tag);
1291 spin_unlock_bh(&cmd->dataout_timeout_lock);
1293 EXPORT_SYMBOL(iscsit_stop_dataout_timer);