Linux 3.11-rc3
[cris-mirror.git] / drivers / target / iscsi / iscsi_target_erl1.c
blob586c268679a450aa9b382d9d42b23ca5dfe0cf35
1 /*******************************************************************************
2 * This file contains error recovery level one used by the iSCSI Target driver.
4 * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
6 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
8 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 ******************************************************************************/
21 #include <linux/list.h>
22 #include <scsi/iscsi_proto.h>
23 #include <target/target_core_base.h>
24 #include <target/target_core_fabric.h>
25 #include <target/iscsi/iscsi_transport.h>
27 #include "iscsi_target_core.h"
28 #include "iscsi_target_seq_pdu_list.h"
29 #include "iscsi_target_datain_values.h"
30 #include "iscsi_target_device.h"
31 #include "iscsi_target_tpg.h"
32 #include "iscsi_target_util.h"
33 #include "iscsi_target_erl0.h"
34 #include "iscsi_target_erl1.h"
35 #include "iscsi_target_erl2.h"
36 #include "iscsi_target.h"
38 #define OFFLOAD_BUF_SIZE 32768
41 * Used to dump excess datain payload for certain error recovery
42 * situations. Receive in OFFLOAD_BUF_SIZE max of datain per rx_data().
44 * dump_padding_digest denotes if padding and data digests need
45 * to be dumped.
47 int iscsit_dump_data_payload(
48 struct iscsi_conn *conn,
49 u32 buf_len,
50 int dump_padding_digest)
52 char *buf, pad_bytes[4];
53 int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got;
54 u32 length, padding, offset = 0, size;
55 struct kvec iov;
57 if (conn->sess->sess_ops->RDMAExtensions)
58 return 0;
60 length = (buf_len > OFFLOAD_BUF_SIZE) ? OFFLOAD_BUF_SIZE : buf_len;
62 buf = kzalloc(length, GFP_ATOMIC);
63 if (!buf) {
64 pr_err("Unable to allocate %u bytes for offload"
65 " buffer.\n", length);
66 return -1;
68 memset(&iov, 0, sizeof(struct kvec));
70 while (offset < buf_len) {
71 size = ((offset + length) > buf_len) ?
72 (buf_len - offset) : length;
74 iov.iov_len = size;
75 iov.iov_base = buf;
77 rx_got = rx_data(conn, &iov, 1, size);
78 if (rx_got != size) {
79 ret = DATAOUT_CANNOT_RECOVER;
80 goto out;
83 offset += size;
86 if (!dump_padding_digest)
87 goto out;
89 padding = ((-buf_len) & 3);
90 if (padding != 0) {
91 iov.iov_len = padding;
92 iov.iov_base = pad_bytes;
94 rx_got = rx_data(conn, &iov, 1, padding);
95 if (rx_got != padding) {
96 ret = DATAOUT_CANNOT_RECOVER;
97 goto out;
101 if (conn->conn_ops->DataDigest) {
102 u32 data_crc;
104 iov.iov_len = ISCSI_CRC_LEN;
105 iov.iov_base = &data_crc;
107 rx_got = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
108 if (rx_got != ISCSI_CRC_LEN) {
109 ret = DATAOUT_CANNOT_RECOVER;
110 goto out;
114 out:
115 kfree(buf);
116 return ret;
120 * Used for retransmitting R2Ts from a R2T SNACK request.
122 static int iscsit_send_recovery_r2t_for_snack(
123 struct iscsi_cmd *cmd,
124 struct iscsi_r2t *r2t)
127 * If the struct iscsi_r2t has not been sent yet, we can safely
128 * ignore retransmission
129 * of the R2TSN in question.
131 spin_lock_bh(&cmd->r2t_lock);
132 if (!r2t->sent_r2t) {
133 spin_unlock_bh(&cmd->r2t_lock);
134 return 0;
136 r2t->sent_r2t = 0;
137 spin_unlock_bh(&cmd->r2t_lock);
139 iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
141 return 0;
144 static int iscsit_handle_r2t_snack(
145 struct iscsi_cmd *cmd,
146 unsigned char *buf,
147 u32 begrun,
148 u32 runlength)
150 u32 last_r2tsn;
151 struct iscsi_r2t *r2t;
154 * Make sure the initiator is not requesting retransmission
155 * of R2TSNs already acknowledged by a TMR TASK_REASSIGN.
157 if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
158 (begrun <= cmd->acked_data_sn)) {
159 pr_err("ITT: 0x%08x, R2T SNACK requesting"
160 " retransmission of R2TSN: 0x%08x to 0x%08x but already"
161 " acked to R2TSN: 0x%08x by TMR TASK_REASSIGN,"
162 " protocol error.\n", cmd->init_task_tag, begrun,
163 (begrun + runlength), cmd->acked_data_sn);
165 return iscsit_reject_cmd(cmd,
166 ISCSI_REASON_PROTOCOL_ERROR, buf);
169 if (runlength) {
170 if ((begrun + runlength) > cmd->r2t_sn) {
171 pr_err("Command ITT: 0x%08x received R2T SNACK"
172 " with BegRun: 0x%08x, RunLength: 0x%08x, exceeds"
173 " current R2TSN: 0x%08x, protocol error.\n",
174 cmd->init_task_tag, begrun, runlength, cmd->r2t_sn);
175 return iscsit_reject_cmd(cmd,
176 ISCSI_REASON_BOOKMARK_INVALID, buf);
178 last_r2tsn = (begrun + runlength);
179 } else
180 last_r2tsn = cmd->r2t_sn;
182 while (begrun < last_r2tsn) {
183 r2t = iscsit_get_holder_for_r2tsn(cmd, begrun);
184 if (!r2t)
185 return -1;
186 if (iscsit_send_recovery_r2t_for_snack(cmd, r2t) < 0)
187 return -1;
189 begrun++;
192 return 0;
196 * Generates Offsets and NextBurstLength based on Begrun and Runlength
197 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
199 * For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only.
201 * FIXME: How is this handled for a RData SNACK?
203 int iscsit_create_recovery_datain_values_datasequenceinorder_yes(
204 struct iscsi_cmd *cmd,
205 struct iscsi_datain_req *dr)
207 u32 data_sn = 0, data_sn_count = 0;
208 u32 pdu_start = 0, seq_no = 0;
209 u32 begrun = dr->begrun;
210 struct iscsi_conn *conn = cmd->conn;
212 while (begrun > data_sn++) {
213 data_sn_count++;
214 if ((dr->next_burst_len +
215 conn->conn_ops->MaxRecvDataSegmentLength) <
216 conn->sess->sess_ops->MaxBurstLength) {
217 dr->read_data_done +=
218 conn->conn_ops->MaxRecvDataSegmentLength;
219 dr->next_burst_len +=
220 conn->conn_ops->MaxRecvDataSegmentLength;
221 } else {
222 dr->read_data_done +=
223 (conn->sess->sess_ops->MaxBurstLength -
224 dr->next_burst_len);
225 dr->next_burst_len = 0;
226 pdu_start += data_sn_count;
227 data_sn_count = 0;
228 seq_no++;
232 if (!conn->sess->sess_ops->DataPDUInOrder) {
233 cmd->seq_no = seq_no;
234 cmd->pdu_start = pdu_start;
235 cmd->pdu_send_order = data_sn_count;
238 return 0;
242 * Generates Offsets and NextBurstLength based on Begrun and Runlength
243 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
245 * For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only.
247 * FIXME: How is this handled for a RData SNACK?
249 int iscsit_create_recovery_datain_values_datasequenceinorder_no(
250 struct iscsi_cmd *cmd,
251 struct iscsi_datain_req *dr)
253 int found_seq = 0, i;
254 u32 data_sn, read_data_done = 0, seq_send_order = 0;
255 u32 begrun = dr->begrun;
256 u32 runlength = dr->runlength;
257 struct iscsi_conn *conn = cmd->conn;
258 struct iscsi_seq *first_seq = NULL, *seq = NULL;
260 if (!cmd->seq_list) {
261 pr_err("struct iscsi_cmd->seq_list is NULL!\n");
262 return -1;
266 * Calculate read_data_done for all sequences containing a
267 * first_datasn and last_datasn less than the BegRun.
269 * Locate the struct iscsi_seq the BegRun lies within and calculate
270 * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength.
272 * Also use struct iscsi_seq->seq_send_order to determine where to start.
274 for (i = 0; i < cmd->seq_count; i++) {
275 seq = &cmd->seq_list[i];
277 if (!seq->seq_send_order)
278 first_seq = seq;
281 * No data has been transferred for this DataIN sequence, so the
282 * seq->first_datasn and seq->last_datasn have not been set.
284 if (!seq->sent) {
285 pr_err("Ignoring non-sent sequence 0x%08x ->"
286 " 0x%08x\n\n", seq->first_datasn,
287 seq->last_datasn);
288 continue;
292 * This DataIN sequence is precedes the received BegRun, add the
293 * total xfer_len of the sequence to read_data_done and reset
294 * seq->pdu_send_order.
296 if ((seq->first_datasn < begrun) &&
297 (seq->last_datasn < begrun)) {
298 pr_err("Pre BegRun sequence 0x%08x ->"
299 " 0x%08x\n", seq->first_datasn,
300 seq->last_datasn);
302 read_data_done += cmd->seq_list[i].xfer_len;
303 seq->next_burst_len = seq->pdu_send_order = 0;
304 continue;
308 * The BegRun lies within this DataIN sequence.
310 if ((seq->first_datasn <= begrun) &&
311 (seq->last_datasn >= begrun)) {
312 pr_err("Found sequence begrun: 0x%08x in"
313 " 0x%08x -> 0x%08x\n", begrun,
314 seq->first_datasn, seq->last_datasn);
316 seq_send_order = seq->seq_send_order;
317 data_sn = seq->first_datasn;
318 seq->next_burst_len = seq->pdu_send_order = 0;
319 found_seq = 1;
322 * For DataPDUInOrder=Yes, while the first DataSN of
323 * the sequence is less than the received BegRun, add
324 * the MaxRecvDataSegmentLength to read_data_done and
325 * to the sequence's next_burst_len;
327 * For DataPDUInOrder=No, while the first DataSN of the
328 * sequence is less than the received BegRun, find the
329 * struct iscsi_pdu of the DataSN in question and add the
330 * MaxRecvDataSegmentLength to read_data_done and to the
331 * sequence's next_burst_len;
333 if (conn->sess->sess_ops->DataPDUInOrder) {
334 while (data_sn < begrun) {
335 seq->pdu_send_order++;
336 read_data_done +=
337 conn->conn_ops->MaxRecvDataSegmentLength;
338 seq->next_burst_len +=
339 conn->conn_ops->MaxRecvDataSegmentLength;
340 data_sn++;
342 } else {
343 int j;
344 struct iscsi_pdu *pdu;
346 while (data_sn < begrun) {
347 seq->pdu_send_order++;
349 for (j = 0; j < seq->pdu_count; j++) {
350 pdu = &cmd->pdu_list[
351 seq->pdu_start + j];
352 if (pdu->data_sn == data_sn) {
353 read_data_done +=
354 pdu->length;
355 seq->next_burst_len +=
356 pdu->length;
359 data_sn++;
362 continue;
366 * This DataIN sequence is larger than the received BegRun,
367 * reset seq->pdu_send_order and continue.
369 if ((seq->first_datasn > begrun) ||
370 (seq->last_datasn > begrun)) {
371 pr_err("Post BegRun sequence 0x%08x -> 0x%08x\n",
372 seq->first_datasn, seq->last_datasn);
374 seq->next_burst_len = seq->pdu_send_order = 0;
375 continue;
379 if (!found_seq) {
380 if (!begrun) {
381 if (!first_seq) {
382 pr_err("ITT: 0x%08x, Begrun: 0x%08x"
383 " but first_seq is NULL\n",
384 cmd->init_task_tag, begrun);
385 return -1;
387 seq_send_order = first_seq->seq_send_order;
388 seq->next_burst_len = seq->pdu_send_order = 0;
389 goto done;
392 pr_err("Unable to locate struct iscsi_seq for ITT: 0x%08x,"
393 " BegRun: 0x%08x, RunLength: 0x%08x while"
394 " DataSequenceInOrder=No and DataPDUInOrder=%s.\n",
395 cmd->init_task_tag, begrun, runlength,
396 (conn->sess->sess_ops->DataPDUInOrder) ? "Yes" : "No");
397 return -1;
400 done:
401 dr->read_data_done = read_data_done;
402 dr->seq_send_order = seq_send_order;
404 return 0;
407 static int iscsit_handle_recovery_datain(
408 struct iscsi_cmd *cmd,
409 unsigned char *buf,
410 u32 begrun,
411 u32 runlength)
413 struct iscsi_conn *conn = cmd->conn;
414 struct iscsi_datain_req *dr;
415 struct se_cmd *se_cmd = &cmd->se_cmd;
417 if (!(se_cmd->transport_state & CMD_T_COMPLETE)) {
418 pr_err("Ignoring ITT: 0x%08x Data SNACK\n",
419 cmd->init_task_tag);
420 return 0;
424 * Make sure the initiator is not requesting retransmission
425 * of DataSNs already acknowledged by a Data ACK SNACK.
427 if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
428 (begrun <= cmd->acked_data_sn)) {
429 pr_err("ITT: 0x%08x, Data SNACK requesting"
430 " retransmission of DataSN: 0x%08x to 0x%08x but"
431 " already acked to DataSN: 0x%08x by Data ACK SNACK,"
432 " protocol error.\n", cmd->init_task_tag, begrun,
433 (begrun + runlength), cmd->acked_data_sn);
435 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
439 * Make sure BegRun and RunLength in the Data SNACK are sane.
440 * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent.
442 if ((begrun + runlength) > (cmd->data_sn - 1)) {
443 pr_err("Initiator requesting BegRun: 0x%08x, RunLength"
444 ": 0x%08x greater than maximum DataSN: 0x%08x.\n",
445 begrun, runlength, (cmd->data_sn - 1));
446 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID,
447 buf);
450 dr = iscsit_allocate_datain_req();
451 if (!dr)
452 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
453 buf);
455 dr->data_sn = dr->begrun = begrun;
456 dr->runlength = runlength;
457 dr->generate_recovery_values = 1;
458 dr->recovery = DATAIN_WITHIN_COMMAND_RECOVERY;
460 iscsit_attach_datain_req(cmd, dr);
462 cmd->i_state = ISTATE_SEND_DATAIN;
463 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
465 return 0;
468 int iscsit_handle_recovery_datain_or_r2t(
469 struct iscsi_conn *conn,
470 unsigned char *buf,
471 itt_t init_task_tag,
472 u32 targ_xfer_tag,
473 u32 begrun,
474 u32 runlength)
476 struct iscsi_cmd *cmd;
478 cmd = iscsit_find_cmd_from_itt(conn, init_task_tag);
479 if (!cmd)
480 return 0;
483 * FIXME: This will not work for bidi commands.
485 switch (cmd->data_direction) {
486 case DMA_TO_DEVICE:
487 return iscsit_handle_r2t_snack(cmd, buf, begrun, runlength);
488 case DMA_FROM_DEVICE:
489 return iscsit_handle_recovery_datain(cmd, buf, begrun,
490 runlength);
491 default:
492 pr_err("Unknown cmd->data_direction: 0x%02x\n",
493 cmd->data_direction);
494 return -1;
497 return 0;
500 /* #warning FIXME: Status SNACK needs to be dependent on OPCODE!!! */
501 int iscsit_handle_status_snack(
502 struct iscsi_conn *conn,
503 itt_t init_task_tag,
504 u32 targ_xfer_tag,
505 u32 begrun,
506 u32 runlength)
508 struct iscsi_cmd *cmd = NULL;
509 u32 last_statsn;
510 int found_cmd;
512 if (conn->exp_statsn > begrun) {
513 pr_err("Got Status SNACK Begrun: 0x%08x, RunLength:"
514 " 0x%08x but already got ExpStatSN: 0x%08x on CID:"
515 " %hu.\n", begrun, runlength, conn->exp_statsn,
516 conn->cid);
517 return 0;
520 last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength);
522 while (begrun < last_statsn) {
523 found_cmd = 0;
525 spin_lock_bh(&conn->cmd_lock);
526 list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
527 if (cmd->stat_sn == begrun) {
528 found_cmd = 1;
529 break;
532 spin_unlock_bh(&conn->cmd_lock);
534 if (!found_cmd) {
535 pr_err("Unable to find StatSN: 0x%08x for"
536 " a Status SNACK, assuming this was a"
537 " protactic SNACK for an untransmitted"
538 " StatSN, ignoring.\n", begrun);
539 begrun++;
540 continue;
543 spin_lock_bh(&cmd->istate_lock);
544 if (cmd->i_state == ISTATE_SEND_DATAIN) {
545 spin_unlock_bh(&cmd->istate_lock);
546 pr_err("Ignoring Status SNACK for BegRun:"
547 " 0x%08x, RunLength: 0x%08x, assuming this was"
548 " a protactic SNACK for an untransmitted"
549 " StatSN\n", begrun, runlength);
550 begrun++;
551 continue;
553 spin_unlock_bh(&cmd->istate_lock);
555 cmd->i_state = ISTATE_SEND_STATUS_RECOVERY;
556 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
557 begrun++;
560 return 0;
563 int iscsit_handle_data_ack(
564 struct iscsi_conn *conn,
565 u32 targ_xfer_tag,
566 u32 begrun,
567 u32 runlength)
569 struct iscsi_cmd *cmd = NULL;
571 cmd = iscsit_find_cmd_from_ttt(conn, targ_xfer_tag);
572 if (!cmd) {
573 pr_err("Data ACK SNACK for TTT: 0x%08x is"
574 " invalid.\n", targ_xfer_tag);
575 return -1;
578 if (begrun <= cmd->acked_data_sn) {
579 pr_err("ITT: 0x%08x Data ACK SNACK BegRUN: 0x%08x is"
580 " less than the already acked DataSN: 0x%08x.\n",
581 cmd->init_task_tag, begrun, cmd->acked_data_sn);
582 return -1;
586 * For Data ACK SNACK, BegRun is the next expected DataSN.
587 * (see iSCSI v19: 10.16.6)
589 cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
590 cmd->acked_data_sn = (begrun - 1);
592 pr_debug("Received Data ACK SNACK for ITT: 0x%08x,"
593 " updated acked DataSN to 0x%08x.\n",
594 cmd->init_task_tag, cmd->acked_data_sn);
596 return 0;
599 static int iscsit_send_recovery_r2t(
600 struct iscsi_cmd *cmd,
601 u32 offset,
602 u32 xfer_len)
604 int ret;
606 spin_lock_bh(&cmd->r2t_lock);
607 ret = iscsit_add_r2t_to_list(cmd, offset, xfer_len, 1, 0);
608 spin_unlock_bh(&cmd->r2t_lock);
610 return ret;
613 int iscsit_dataout_datapduinorder_no_fbit(
614 struct iscsi_cmd *cmd,
615 struct iscsi_pdu *pdu)
617 int i, send_recovery_r2t = 0, recovery = 0;
618 u32 length = 0, offset = 0, pdu_count = 0, xfer_len = 0;
619 struct iscsi_conn *conn = cmd->conn;
620 struct iscsi_pdu *first_pdu = NULL;
623 * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count
624 * of the DataOUT sequence.
626 if (conn->sess->sess_ops->DataSequenceInOrder) {
627 for (i = 0; i < cmd->pdu_count; i++) {
628 if (cmd->pdu_list[i].seq_no == pdu->seq_no) {
629 if (!first_pdu)
630 first_pdu = &cmd->pdu_list[i];
631 xfer_len += cmd->pdu_list[i].length;
632 pdu_count++;
633 } else if (pdu_count)
634 break;
636 } else {
637 struct iscsi_seq *seq = cmd->seq_ptr;
639 first_pdu = &cmd->pdu_list[seq->pdu_start];
640 pdu_count = seq->pdu_count;
643 if (!first_pdu || !pdu_count)
644 return DATAOUT_CANNOT_RECOVER;
647 * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu.
648 * The following ugly logic does batching of not received PDUs.
650 for (i = 0; i < pdu_count; i++) {
651 if (first_pdu[i].status == ISCSI_PDU_RECEIVED_OK) {
652 if (!send_recovery_r2t)
653 continue;
655 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
656 return DATAOUT_CANNOT_RECOVER;
658 send_recovery_r2t = length = offset = 0;
659 continue;
662 * Set recovery = 1 for any missing, CRC failed, or timed
663 * out PDUs to let the DataOUT logic know that this sequence
664 * has not been completed yet.
666 * Also, only send a Recovery R2T for ISCSI_PDU_NOT_RECEIVED.
667 * We assume if the PDU either failed CRC or timed out
668 * that a Recovery R2T has already been sent.
670 recovery = 1;
672 if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED)
673 continue;
675 if (!offset)
676 offset = first_pdu[i].offset;
677 length += first_pdu[i].length;
679 send_recovery_r2t = 1;
682 if (send_recovery_r2t)
683 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
684 return DATAOUT_CANNOT_RECOVER;
686 return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY;
689 static int iscsit_recalculate_dataout_values(
690 struct iscsi_cmd *cmd,
691 u32 pdu_offset,
692 u32 pdu_length,
693 u32 *r2t_offset,
694 u32 *r2t_length)
696 int i;
697 struct iscsi_conn *conn = cmd->conn;
698 struct iscsi_pdu *pdu = NULL;
700 if (conn->sess->sess_ops->DataSequenceInOrder) {
701 cmd->data_sn = 0;
703 if (conn->sess->sess_ops->DataPDUInOrder) {
704 *r2t_offset = cmd->write_data_done;
705 *r2t_length = (cmd->seq_end_offset -
706 cmd->write_data_done);
707 return 0;
710 *r2t_offset = cmd->seq_start_offset;
711 *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset);
713 for (i = 0; i < cmd->pdu_count; i++) {
714 pdu = &cmd->pdu_list[i];
716 if (pdu->status != ISCSI_PDU_RECEIVED_OK)
717 continue;
719 if ((pdu->offset >= cmd->seq_start_offset) &&
720 ((pdu->offset + pdu->length) <=
721 cmd->seq_end_offset)) {
722 if (!cmd->unsolicited_data)
723 cmd->next_burst_len -= pdu->length;
724 else
725 cmd->first_burst_len -= pdu->length;
727 cmd->write_data_done -= pdu->length;
728 pdu->status = ISCSI_PDU_NOT_RECEIVED;
731 } else {
732 struct iscsi_seq *seq = NULL;
734 seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length);
735 if (!seq)
736 return -1;
738 *r2t_offset = seq->orig_offset;
739 *r2t_length = seq->xfer_len;
741 cmd->write_data_done -= (seq->offset - seq->orig_offset);
742 if (cmd->immediate_data)
743 cmd->first_burst_len = cmd->write_data_done;
745 seq->data_sn = 0;
746 seq->offset = seq->orig_offset;
747 seq->next_burst_len = 0;
748 seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY;
750 if (conn->sess->sess_ops->DataPDUInOrder)
751 return 0;
753 for (i = 0; i < seq->pdu_count; i++) {
754 pdu = &cmd->pdu_list[i+seq->pdu_start];
756 if (pdu->status != ISCSI_PDU_RECEIVED_OK)
757 continue;
759 pdu->status = ISCSI_PDU_NOT_RECEIVED;
763 return 0;
766 int iscsit_recover_dataout_sequence(
767 struct iscsi_cmd *cmd,
768 u32 pdu_offset,
769 u32 pdu_length)
771 u32 r2t_length = 0, r2t_offset = 0;
773 spin_lock_bh(&cmd->istate_lock);
774 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
775 spin_unlock_bh(&cmd->istate_lock);
777 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
778 &r2t_offset, &r2t_length) < 0)
779 return DATAOUT_CANNOT_RECOVER;
781 iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length);
783 return DATAOUT_WITHIN_COMMAND_RECOVERY;
786 static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void)
788 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL;
790 ooo_cmdsn = kmem_cache_zalloc(lio_ooo_cache, GFP_ATOMIC);
791 if (!ooo_cmdsn) {
792 pr_err("Unable to allocate memory for"
793 " struct iscsi_ooo_cmdsn.\n");
794 return NULL;
796 INIT_LIST_HEAD(&ooo_cmdsn->ooo_list);
798 return ooo_cmdsn;
802 * Called with sess->cmdsn_mutex held.
804 static int iscsit_attach_ooo_cmdsn(
805 struct iscsi_session *sess,
806 struct iscsi_ooo_cmdsn *ooo_cmdsn)
808 struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp;
810 * We attach the struct iscsi_ooo_cmdsn entry to the out of order
811 * list in increasing CmdSN order.
812 * This allows iscsi_execute_ooo_cmdsns() to detect any
813 * additional CmdSN holes while performing delayed execution.
815 if (list_empty(&sess->sess_ooo_cmdsn_list))
816 list_add_tail(&ooo_cmdsn->ooo_list,
817 &sess->sess_ooo_cmdsn_list);
818 else {
819 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
820 typeof(*ooo_tail), ooo_list);
822 * CmdSN is greater than the tail of the list.
824 if (iscsi_sna_lt(ooo_tail->cmdsn, ooo_cmdsn->cmdsn))
825 list_add_tail(&ooo_cmdsn->ooo_list,
826 &sess->sess_ooo_cmdsn_list);
827 else {
829 * CmdSN is either lower than the head, or somewhere
830 * in the middle.
832 list_for_each_entry(ooo_tmp, &sess->sess_ooo_cmdsn_list,
833 ooo_list) {
834 if (iscsi_sna_lt(ooo_tmp->cmdsn, ooo_cmdsn->cmdsn))
835 continue;
837 /* Insert before this entry */
838 list_add(&ooo_cmdsn->ooo_list,
839 ooo_tmp->ooo_list.prev);
840 break;
845 return 0;
849 * Removes an struct iscsi_ooo_cmdsn from a session's list,
850 * called with struct iscsi_session->cmdsn_mutex held.
852 void iscsit_remove_ooo_cmdsn(
853 struct iscsi_session *sess,
854 struct iscsi_ooo_cmdsn *ooo_cmdsn)
856 list_del(&ooo_cmdsn->ooo_list);
857 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
860 void iscsit_clear_ooo_cmdsns_for_conn(struct iscsi_conn *conn)
862 struct iscsi_ooo_cmdsn *ooo_cmdsn;
863 struct iscsi_session *sess = conn->sess;
865 mutex_lock(&sess->cmdsn_mutex);
866 list_for_each_entry(ooo_cmdsn, &sess->sess_ooo_cmdsn_list, ooo_list) {
867 if (ooo_cmdsn->cid != conn->cid)
868 continue;
870 ooo_cmdsn->cmd = NULL;
872 mutex_unlock(&sess->cmdsn_mutex);
876 * Called with sess->cmdsn_mutex held.
878 int iscsit_execute_ooo_cmdsns(struct iscsi_session *sess)
880 int ooo_count = 0;
881 struct iscsi_cmd *cmd = NULL;
882 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
884 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
885 &sess->sess_ooo_cmdsn_list, ooo_list) {
886 if (ooo_cmdsn->cmdsn != sess->exp_cmd_sn)
887 continue;
889 if (!ooo_cmdsn->cmd) {
890 sess->exp_cmd_sn++;
891 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
892 continue;
895 cmd = ooo_cmdsn->cmd;
896 cmd->i_state = cmd->deferred_i_state;
897 ooo_count++;
898 sess->exp_cmd_sn++;
899 pr_debug("Executing out of order CmdSN: 0x%08x,"
900 " incremented ExpCmdSN to 0x%08x.\n",
901 cmd->cmd_sn, sess->exp_cmd_sn);
903 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
905 if (iscsit_execute_cmd(cmd, 1) < 0)
906 return -1;
908 continue;
911 return ooo_count;
915 * Called either:
917 * 1. With sess->cmdsn_mutex held from iscsi_execute_ooo_cmdsns()
918 * or iscsi_check_received_cmdsn().
919 * 2. With no locks held directly from iscsi_handle_XXX_pdu() functions
920 * for immediate commands.
922 int iscsit_execute_cmd(struct iscsi_cmd *cmd, int ooo)
924 struct se_cmd *se_cmd = &cmd->se_cmd;
925 struct iscsi_conn *conn = cmd->conn;
926 int lr = 0;
928 spin_lock_bh(&cmd->istate_lock);
929 if (ooo)
930 cmd->cmd_flags &= ~ICF_OOO_CMDSN;
932 switch (cmd->iscsi_opcode) {
933 case ISCSI_OP_SCSI_CMD:
935 * Go ahead and send the CHECK_CONDITION status for
936 * any SCSI CDB exceptions that may have occurred.
938 if (cmd->sense_reason) {
939 if (cmd->sense_reason == TCM_RESERVATION_CONFLICT) {
940 cmd->i_state = ISTATE_SEND_STATUS;
941 spin_unlock_bh(&cmd->istate_lock);
942 iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
943 cmd->i_state);
944 return 0;
946 spin_unlock_bh(&cmd->istate_lock);
948 * Determine if delayed TASK_ABORTED status for WRITEs
949 * should be sent now if no unsolicited data out
950 * payloads are expected, or if the delayed status
951 * should be sent after unsolicited data out with
952 * ISCSI_FLAG_CMD_FINAL set in iscsi_handle_data_out()
954 if (transport_check_aborted_status(se_cmd,
955 (cmd->unsolicited_data == 0)) != 0)
956 return 0;
958 * Otherwise send CHECK_CONDITION and sense for
959 * exception
961 return transport_send_check_condition_and_sense(se_cmd,
962 cmd->sense_reason, 0);
965 * Special case for delayed CmdSN with Immediate
966 * Data and/or Unsolicited Data Out attached.
968 if (cmd->immediate_data) {
969 if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
970 spin_unlock_bh(&cmd->istate_lock);
971 target_execute_cmd(&cmd->se_cmd);
972 return 0;
974 spin_unlock_bh(&cmd->istate_lock);
976 if (!(cmd->cmd_flags &
977 ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
979 * Send the delayed TASK_ABORTED status for
980 * WRITEs if no more unsolicitied data is
981 * expected.
983 if (transport_check_aborted_status(se_cmd, 1)
984 != 0)
985 return 0;
987 iscsit_set_dataout_sequence_values(cmd);
988 conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
990 return 0;
993 * The default handler.
995 spin_unlock_bh(&cmd->istate_lock);
997 if ((cmd->data_direction == DMA_TO_DEVICE) &&
998 !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
1000 * Send the delayed TASK_ABORTED status for WRITEs if
1001 * no more nsolicitied data is expected.
1003 if (transport_check_aborted_status(se_cmd, 1) != 0)
1004 return 0;
1006 iscsit_set_unsoliticed_dataout(cmd);
1008 return transport_handle_cdb_direct(&cmd->se_cmd);
1010 case ISCSI_OP_NOOP_OUT:
1011 case ISCSI_OP_TEXT:
1012 spin_unlock_bh(&cmd->istate_lock);
1013 iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
1014 break;
1015 case ISCSI_OP_SCSI_TMFUNC:
1016 if (cmd->se_cmd.se_tmr_req->response) {
1017 spin_unlock_bh(&cmd->istate_lock);
1018 iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
1019 cmd->i_state);
1020 return 0;
1022 spin_unlock_bh(&cmd->istate_lock);
1024 return transport_generic_handle_tmr(&cmd->se_cmd);
1025 case ISCSI_OP_LOGOUT:
1026 spin_unlock_bh(&cmd->istate_lock);
1027 switch (cmd->logout_reason) {
1028 case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
1029 lr = iscsit_logout_closesession(cmd, cmd->conn);
1030 break;
1031 case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
1032 lr = iscsit_logout_closeconnection(cmd, cmd->conn);
1033 break;
1034 case ISCSI_LOGOUT_REASON_RECOVERY:
1035 lr = iscsit_logout_removeconnforrecovery(cmd, cmd->conn);
1036 break;
1037 default:
1038 pr_err("Unknown iSCSI Logout Request Code:"
1039 " 0x%02x\n", cmd->logout_reason);
1040 return -1;
1043 return lr;
1044 default:
1045 spin_unlock_bh(&cmd->istate_lock);
1046 pr_err("Cannot perform out of order execution for"
1047 " unknown iSCSI Opcode: 0x%02x\n", cmd->iscsi_opcode);
1048 return -1;
1051 return 0;
1054 void iscsit_free_all_ooo_cmdsns(struct iscsi_session *sess)
1056 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
1058 mutex_lock(&sess->cmdsn_mutex);
1059 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
1060 &sess->sess_ooo_cmdsn_list, ooo_list) {
1062 list_del(&ooo_cmdsn->ooo_list);
1063 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1065 mutex_unlock(&sess->cmdsn_mutex);
1068 int iscsit_handle_ooo_cmdsn(
1069 struct iscsi_session *sess,
1070 struct iscsi_cmd *cmd,
1071 u32 cmdsn)
1073 int batch = 0;
1074 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL;
1076 cmd->deferred_i_state = cmd->i_state;
1077 cmd->i_state = ISTATE_DEFERRED_CMD;
1078 cmd->cmd_flags |= ICF_OOO_CMDSN;
1080 if (list_empty(&sess->sess_ooo_cmdsn_list))
1081 batch = 1;
1082 else {
1083 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
1084 typeof(*ooo_tail), ooo_list);
1085 if (ooo_tail->cmdsn != (cmdsn - 1))
1086 batch = 1;
1089 ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
1090 if (!ooo_cmdsn)
1091 return -ENOMEM;
1093 ooo_cmdsn->cmd = cmd;
1094 ooo_cmdsn->batch_count = (batch) ?
1095 (cmdsn - sess->exp_cmd_sn) : 1;
1096 ooo_cmdsn->cid = cmd->conn->cid;
1097 ooo_cmdsn->exp_cmdsn = sess->exp_cmd_sn;
1098 ooo_cmdsn->cmdsn = cmdsn;
1100 if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
1101 kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
1102 return -ENOMEM;
1105 return 0;
1108 static int iscsit_set_dataout_timeout_values(
1109 struct iscsi_cmd *cmd,
1110 u32 *offset,
1111 u32 *length)
1113 struct iscsi_conn *conn = cmd->conn;
1114 struct iscsi_r2t *r2t;
1116 if (cmd->unsolicited_data) {
1117 *offset = 0;
1118 *length = (conn->sess->sess_ops->FirstBurstLength >
1119 cmd->se_cmd.data_length) ?
1120 cmd->se_cmd.data_length :
1121 conn->sess->sess_ops->FirstBurstLength;
1122 return 0;
1125 spin_lock_bh(&cmd->r2t_lock);
1126 if (list_empty(&cmd->cmd_r2t_list)) {
1127 pr_err("cmd->cmd_r2t_list is empty!\n");
1128 spin_unlock_bh(&cmd->r2t_lock);
1129 return -1;
1132 list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
1133 if (r2t->sent_r2t && !r2t->recovery_r2t && !r2t->seq_complete) {
1134 *offset = r2t->offset;
1135 *length = r2t->xfer_len;
1136 spin_unlock_bh(&cmd->r2t_lock);
1137 return 0;
1140 spin_unlock_bh(&cmd->r2t_lock);
1142 pr_err("Unable to locate any incomplete DataOUT"
1143 " sequences for ITT: 0x%08x.\n", cmd->init_task_tag);
1145 return -1;
1149 * NOTE: Called from interrupt (timer) context.
1151 static void iscsit_handle_dataout_timeout(unsigned long data)
1153 u32 pdu_length = 0, pdu_offset = 0;
1154 u32 r2t_length = 0, r2t_offset = 0;
1155 struct iscsi_cmd *cmd = (struct iscsi_cmd *) data;
1156 struct iscsi_conn *conn = cmd->conn;
1157 struct iscsi_session *sess = NULL;
1158 struct iscsi_node_attrib *na;
1160 iscsit_inc_conn_usage_count(conn);
1162 spin_lock_bh(&cmd->dataout_timeout_lock);
1163 if (cmd->dataout_timer_flags & ISCSI_TF_STOP) {
1164 spin_unlock_bh(&cmd->dataout_timeout_lock);
1165 iscsit_dec_conn_usage_count(conn);
1166 return;
1168 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1169 sess = conn->sess;
1170 na = iscsit_tpg_get_node_attrib(sess);
1172 if (!sess->sess_ops->ErrorRecoveryLevel) {
1173 pr_debug("Unable to recover from DataOut timeout while"
1174 " in ERL=0.\n");
1175 goto failure;
1178 if (++cmd->dataout_timeout_retries == na->dataout_timeout_retries) {
1179 pr_debug("Command ITT: 0x%08x exceeded max retries"
1180 " for DataOUT timeout %u, closing iSCSI connection.\n",
1181 cmd->init_task_tag, na->dataout_timeout_retries);
1182 goto failure;
1185 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
1187 if (conn->sess->sess_ops->DataSequenceInOrder) {
1188 if (conn->sess->sess_ops->DataPDUInOrder) {
1189 pdu_offset = cmd->write_data_done;
1190 if ((pdu_offset + (conn->sess->sess_ops->MaxBurstLength -
1191 cmd->next_burst_len)) > cmd->se_cmd.data_length)
1192 pdu_length = (cmd->se_cmd.data_length -
1193 cmd->write_data_done);
1194 else
1195 pdu_length = (conn->sess->sess_ops->MaxBurstLength -
1196 cmd->next_burst_len);
1197 } else {
1198 pdu_offset = cmd->seq_start_offset;
1199 pdu_length = (cmd->seq_end_offset -
1200 cmd->seq_start_offset);
1202 } else {
1203 if (iscsit_set_dataout_timeout_values(cmd, &pdu_offset,
1204 &pdu_length) < 0)
1205 goto failure;
1208 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
1209 &r2t_offset, &r2t_length) < 0)
1210 goto failure;
1212 pr_debug("Command ITT: 0x%08x timed out waiting for"
1213 " completion of %sDataOUT Sequence Offset: %u, Length: %u\n",
1214 cmd->init_task_tag, (cmd->unsolicited_data) ? "Unsolicited " :
1215 "", r2t_offset, r2t_length);
1217 if (iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length) < 0)
1218 goto failure;
1220 iscsit_start_dataout_timer(cmd, conn);
1221 spin_unlock_bh(&cmd->dataout_timeout_lock);
1222 iscsit_dec_conn_usage_count(conn);
1224 return;
1226 failure:
1227 spin_unlock_bh(&cmd->dataout_timeout_lock);
1228 iscsit_cause_connection_reinstatement(conn, 0);
1229 iscsit_dec_conn_usage_count(conn);
1232 void iscsit_mod_dataout_timer(struct iscsi_cmd *cmd)
1234 struct iscsi_conn *conn = cmd->conn;
1235 struct iscsi_session *sess = conn->sess;
1236 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1238 spin_lock_bh(&cmd->dataout_timeout_lock);
1239 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1240 spin_unlock_bh(&cmd->dataout_timeout_lock);
1241 return;
1244 mod_timer(&cmd->dataout_timer,
1245 (get_jiffies_64() + na->dataout_timeout * HZ));
1246 pr_debug("Updated DataOUT timer for ITT: 0x%08x",
1247 cmd->init_task_tag);
1248 spin_unlock_bh(&cmd->dataout_timeout_lock);
1252 * Called with cmd->dataout_timeout_lock held.
1254 void iscsit_start_dataout_timer(
1255 struct iscsi_cmd *cmd,
1256 struct iscsi_conn *conn)
1258 struct iscsi_session *sess = conn->sess;
1259 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1261 if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING)
1262 return;
1264 pr_debug("Starting DataOUT timer for ITT: 0x%08x on"
1265 " CID: %hu.\n", cmd->init_task_tag, conn->cid);
1267 init_timer(&cmd->dataout_timer);
1268 cmd->dataout_timer.expires = (get_jiffies_64() + na->dataout_timeout * HZ);
1269 cmd->dataout_timer.data = (unsigned long)cmd;
1270 cmd->dataout_timer.function = iscsit_handle_dataout_timeout;
1271 cmd->dataout_timer_flags &= ~ISCSI_TF_STOP;
1272 cmd->dataout_timer_flags |= ISCSI_TF_RUNNING;
1273 add_timer(&cmd->dataout_timer);
1276 void iscsit_stop_dataout_timer(struct iscsi_cmd *cmd)
1278 spin_lock_bh(&cmd->dataout_timeout_lock);
1279 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
1280 spin_unlock_bh(&cmd->dataout_timeout_lock);
1281 return;
1283 cmd->dataout_timer_flags |= ISCSI_TF_STOP;
1284 spin_unlock_bh(&cmd->dataout_timeout_lock);
1286 del_timer_sync(&cmd->dataout_timer);
1288 spin_lock_bh(&cmd->dataout_timeout_lock);
1289 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
1290 pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n",
1291 cmd->init_task_tag);
1292 spin_unlock_bh(&cmd->dataout_timeout_lock);
1294 EXPORT_SYMBOL(iscsit_stop_dataout_timer);