1 /******************************************************************************* 2 * This file contains error recovery level one used by the iSCSI Target driver. 3 * 4 * (c) Copyright 2007-2013 Datera, Inc. 5 * 6 * Author: Nicholas A. Bellinger <nab@linux-iscsi.org> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 ******************************************************************************/ 18 19 #include <linux/list.h> 20 #include <linux/slab.h> 21 #include <scsi/iscsi_proto.h> 22 #include <target/target_core_base.h> 23 #include <target/target_core_fabric.h> 24 #include <target/iscsi/iscsi_transport.h> 25 26 #include <target/iscsi/iscsi_target_core.h> 27 #include "iscsi_target_seq_pdu_list.h" 28 #include "iscsi_target_datain_values.h" 29 #include "iscsi_target_device.h" 30 #include "iscsi_target_tpg.h" 31 #include "iscsi_target_util.h" 32 #include "iscsi_target_erl0.h" 33 #include "iscsi_target_erl1.h" 34 #include "iscsi_target_erl2.h" 35 #include "iscsi_target.h" 36 37 #define OFFLOAD_BUF_SIZE 32768U 38 39 /* 40 * Used to dump excess datain payload for certain error recovery 41 * situations. Receive in OFFLOAD_BUF_SIZE max of datain per rx_data(). 42 * 43 * dump_padding_digest denotes if padding and data digests need 44 * to be dumped. 45 */ 46 int iscsit_dump_data_payload( 47 struct iscsi_conn *conn, 48 u32 buf_len, 49 int dump_padding_digest) 50 { 51 char *buf, pad_bytes[4]; 52 int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got; 53 u32 length, padding, offset = 0, size; 54 struct kvec iov; 55 56 if (conn->sess->sess_ops->RDMAExtensions) 57 return 0; 58 59 length = min(buf_len, OFFLOAD_BUF_SIZE); 60 61 buf = kzalloc(length, GFP_ATOMIC); 62 if (!buf) { 63 pr_err("Unable to allocate %u bytes for offload" 64 " buffer.\n", length); 65 return -1; 66 } 67 memset(&iov, 0, sizeof(struct kvec)); 68 69 while (offset < buf_len) { 70 size = min(buf_len - offset, length); 71 72 iov.iov_len = size; 73 iov.iov_base = buf; 74 75 rx_got = rx_data(conn, &iov, 1, size); 76 if (rx_got != size) { 77 ret = DATAOUT_CANNOT_RECOVER; 78 goto out; 79 } 80 81 offset += size; 82 } 83 84 if (!dump_padding_digest) 85 goto out; 86 87 padding = ((-buf_len) & 3); 88 if (padding != 0) { 89 iov.iov_len = padding; 90 iov.iov_base = pad_bytes; 91 92 rx_got = rx_data(conn, &iov, 1, padding); 93 if (rx_got != padding) { 94 ret = DATAOUT_CANNOT_RECOVER; 95 goto out; 96 } 97 } 98 99 if (conn->conn_ops->DataDigest) { 100 u32 data_crc; 101 102 iov.iov_len = ISCSI_CRC_LEN; 103 iov.iov_base = &data_crc; 104 105 rx_got = rx_data(conn, &iov, 1, ISCSI_CRC_LEN); 106 if (rx_got != ISCSI_CRC_LEN) { 107 ret = DATAOUT_CANNOT_RECOVER; 108 goto out; 109 } 110 } 111 112 out: 113 kfree(buf); 114 return ret; 115 } 116 117 /* 118 * Used for retransmitting R2Ts from a R2T SNACK request. 119 */ 120 static int iscsit_send_recovery_r2t_for_snack( 121 struct iscsi_cmd *cmd, 122 struct iscsi_r2t *r2t) 123 { 124 /* 125 * If the struct iscsi_r2t has not been sent yet, we can safely 126 * ignore retransmission 127 * of the R2TSN in question. 128 */ 129 spin_lock_bh(&cmd->r2t_lock); 130 if (!r2t->sent_r2t) { 131 spin_unlock_bh(&cmd->r2t_lock); 132 return 0; 133 } 134 r2t->sent_r2t = 0; 135 spin_unlock_bh(&cmd->r2t_lock); 136 137 iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T); 138 139 return 0; 140 } 141 142 static int iscsit_handle_r2t_snack( 143 struct iscsi_cmd *cmd, 144 unsigned char *buf, 145 u32 begrun, 146 u32 runlength) 147 { 148 u32 last_r2tsn; 149 struct iscsi_r2t *r2t; 150 151 /* 152 * Make sure the initiator is not requesting retransmission 153 * of R2TSNs already acknowledged by a TMR TASK_REASSIGN. 154 */ 155 if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) && 156 (begrun <= cmd->acked_data_sn)) { 157 pr_err("ITT: 0x%08x, R2T SNACK requesting" 158 " retransmission of R2TSN: 0x%08x to 0x%08x but already" 159 " acked to R2TSN: 0x%08x by TMR TASK_REASSIGN," 160 " protocol error.\n", cmd->init_task_tag, begrun, 161 (begrun + runlength), cmd->acked_data_sn); 162 163 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf); 164 } 165 166 if (runlength) { 167 if ((begrun + runlength) > cmd->r2t_sn) { 168 pr_err("Command ITT: 0x%08x received R2T SNACK" 169 " with BegRun: 0x%08x, RunLength: 0x%08x, exceeds" 170 " current R2TSN: 0x%08x, protocol error.\n", 171 cmd->init_task_tag, begrun, runlength, cmd->r2t_sn); 172 return iscsit_reject_cmd(cmd, 173 ISCSI_REASON_BOOKMARK_INVALID, buf); 174 } 175 last_r2tsn = (begrun + runlength); 176 } else 177 last_r2tsn = cmd->r2t_sn; 178 179 while (begrun < last_r2tsn) { 180 r2t = iscsit_get_holder_for_r2tsn(cmd, begrun); 181 if (!r2t) 182 return -1; 183 if (iscsit_send_recovery_r2t_for_snack(cmd, r2t) < 0) 184 return -1; 185 186 begrun++; 187 } 188 189 return 0; 190 } 191 192 /* 193 * Generates Offsets and NextBurstLength based on Begrun and Runlength 194 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN. 195 * 196 * For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only. 197 * 198 * FIXME: How is this handled for a RData SNACK? 199 */ 200 int iscsit_create_recovery_datain_values_datasequenceinorder_yes( 201 struct iscsi_cmd *cmd, 202 struct iscsi_datain_req *dr) 203 { 204 u32 data_sn = 0, data_sn_count = 0; 205 u32 pdu_start = 0, seq_no = 0; 206 u32 begrun = dr->begrun; 207 struct iscsi_conn *conn = cmd->conn; 208 209 while (begrun > data_sn++) { 210 data_sn_count++; 211 if ((dr->next_burst_len + 212 conn->conn_ops->MaxRecvDataSegmentLength) < 213 conn->sess->sess_ops->MaxBurstLength) { 214 dr->read_data_done += 215 conn->conn_ops->MaxRecvDataSegmentLength; 216 dr->next_burst_len += 217 conn->conn_ops->MaxRecvDataSegmentLength; 218 } else { 219 dr->read_data_done += 220 (conn->sess->sess_ops->MaxBurstLength - 221 dr->next_burst_len); 222 dr->next_burst_len = 0; 223 pdu_start += data_sn_count; 224 data_sn_count = 0; 225 seq_no++; 226 } 227 } 228 229 if (!conn->sess->sess_ops->DataPDUInOrder) { 230 cmd->seq_no = seq_no; 231 cmd->pdu_start = pdu_start; 232 cmd->pdu_send_order = data_sn_count; 233 } 234 235 return 0; 236 } 237 238 /* 239 * Generates Offsets and NextBurstLength based on Begrun and Runlength 240 * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN. 241 * 242 * For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only. 243 * 244 * FIXME: How is this handled for a RData SNACK? 245 */ 246 int iscsit_create_recovery_datain_values_datasequenceinorder_no( 247 struct iscsi_cmd *cmd, 248 struct iscsi_datain_req *dr) 249 { 250 int found_seq = 0, i; 251 u32 data_sn, read_data_done = 0, seq_send_order = 0; 252 u32 begrun = dr->begrun; 253 u32 runlength = dr->runlength; 254 struct iscsi_conn *conn = cmd->conn; 255 struct iscsi_seq *first_seq = NULL, *seq = NULL; 256 257 if (!cmd->seq_list) { 258 pr_err("struct iscsi_cmd->seq_list is NULL!\n"); 259 return -1; 260 } 261 262 /* 263 * Calculate read_data_done for all sequences containing a 264 * first_datasn and last_datasn less than the BegRun. 265 * 266 * Locate the struct iscsi_seq the BegRun lies within and calculate 267 * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength. 268 * 269 * Also use struct iscsi_seq->seq_send_order to determine where to start. 270 */ 271 for (i = 0; i < cmd->seq_count; i++) { 272 seq = &cmd->seq_list[i]; 273 274 if (!seq->seq_send_order) 275 first_seq = seq; 276 277 /* 278 * No data has been transferred for this DataIN sequence, so the 279 * seq->first_datasn and seq->last_datasn have not been set. 280 */ 281 if (!seq->sent) { 282 pr_err("Ignoring non-sent sequence 0x%08x ->" 283 " 0x%08x\n\n", seq->first_datasn, 284 seq->last_datasn); 285 continue; 286 } 287 288 /* 289 * This DataIN sequence is precedes the received BegRun, add the 290 * total xfer_len of the sequence to read_data_done and reset 291 * seq->pdu_send_order. 292 */ 293 if ((seq->first_datasn < begrun) && 294 (seq->last_datasn < begrun)) { 295 pr_err("Pre BegRun sequence 0x%08x ->" 296 " 0x%08x\n", seq->first_datasn, 297 seq->last_datasn); 298 299 read_data_done += cmd->seq_list[i].xfer_len; 300 seq->next_burst_len = seq->pdu_send_order = 0; 301 continue; 302 } 303 304 /* 305 * The BegRun lies within this DataIN sequence. 306 */ 307 if ((seq->first_datasn <= begrun) && 308 (seq->last_datasn >= begrun)) { 309 pr_err("Found sequence begrun: 0x%08x in" 310 " 0x%08x -> 0x%08x\n", begrun, 311 seq->first_datasn, seq->last_datasn); 312 313 seq_send_order = seq->seq_send_order; 314 data_sn = seq->first_datasn; 315 seq->next_burst_len = seq->pdu_send_order = 0; 316 found_seq = 1; 317 318 /* 319 * For DataPDUInOrder=Yes, while the first DataSN of 320 * the sequence is less than the received BegRun, add 321 * the MaxRecvDataSegmentLength to read_data_done and 322 * to the sequence's next_burst_len; 323 * 324 * For DataPDUInOrder=No, while the first DataSN of the 325 * sequence is less than the received BegRun, find the 326 * struct iscsi_pdu of the DataSN in question and add the 327 * MaxRecvDataSegmentLength to read_data_done and to the 328 * sequence's next_burst_len; 329 */ 330 if (conn->sess->sess_ops->DataPDUInOrder) { 331 while (data_sn < begrun) { 332 seq->pdu_send_order++; 333 read_data_done += 334 conn->conn_ops->MaxRecvDataSegmentLength; 335 seq->next_burst_len += 336 conn->conn_ops->MaxRecvDataSegmentLength; 337 data_sn++; 338 } 339 } else { 340 int j; 341 struct iscsi_pdu *pdu; 342 343 while (data_sn < begrun) { 344 seq->pdu_send_order++; 345 346 for (j = 0; j < seq->pdu_count; j++) { 347 pdu = &cmd->pdu_list[ 348 seq->pdu_start + j]; 349 if (pdu->data_sn == data_sn) { 350 read_data_done += 351 pdu->length; 352 seq->next_burst_len += 353 pdu->length; 354 } 355 } 356 data_sn++; 357 } 358 } 359 continue; 360 } 361 362 /* 363 * This DataIN sequence is larger than the received BegRun, 364 * reset seq->pdu_send_order and continue. 365 */ 366 if ((seq->first_datasn > begrun) || 367 (seq->last_datasn > begrun)) { 368 pr_err("Post BegRun sequence 0x%08x -> 0x%08x\n", 369 seq->first_datasn, seq->last_datasn); 370 371 seq->next_burst_len = seq->pdu_send_order = 0; 372 continue; 373 } 374 } 375 376 if (!found_seq) { 377 if (!begrun) { 378 if (!first_seq) { 379 pr_err("ITT: 0x%08x, Begrun: 0x%08x" 380 " but first_seq is NULL\n", 381 cmd->init_task_tag, begrun); 382 return -1; 383 } 384 seq_send_order = first_seq->seq_send_order; 385 seq->next_burst_len = seq->pdu_send_order = 0; 386 goto done; 387 } 388 389 pr_err("Unable to locate struct iscsi_seq for ITT: 0x%08x," 390 " BegRun: 0x%08x, RunLength: 0x%08x while" 391 " DataSequenceInOrder=No and DataPDUInOrder=%s.\n", 392 cmd->init_task_tag, begrun, runlength, 393 (conn->sess->sess_ops->DataPDUInOrder) ? "Yes" : "No"); 394 return -1; 395 } 396 397 done: 398 dr->read_data_done = read_data_done; 399 dr->seq_send_order = seq_send_order; 400 401 return 0; 402 } 403 404 static int iscsit_handle_recovery_datain( 405 struct iscsi_cmd *cmd, 406 unsigned char *buf, 407 u32 begrun, 408 u32 runlength) 409 { 410 struct iscsi_conn *conn = cmd->conn; 411 struct iscsi_datain_req *dr; 412 struct se_cmd *se_cmd = &cmd->se_cmd; 413 414 if (!(se_cmd->transport_state & CMD_T_COMPLETE)) { 415 pr_err("Ignoring ITT: 0x%08x Data SNACK\n", 416 cmd->init_task_tag); 417 return 0; 418 } 419 420 /* 421 * Make sure the initiator is not requesting retransmission 422 * of DataSNs already acknowledged by a Data ACK SNACK. 423 */ 424 if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) && 425 (begrun <= cmd->acked_data_sn)) { 426 pr_err("ITT: 0x%08x, Data SNACK requesting" 427 " retransmission of DataSN: 0x%08x to 0x%08x but" 428 " already acked to DataSN: 0x%08x by Data ACK SNACK," 429 " protocol error.\n", cmd->init_task_tag, begrun, 430 (begrun + runlength), cmd->acked_data_sn); 431 432 return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf); 433 } 434 435 /* 436 * Make sure BegRun and RunLength in the Data SNACK are sane. 437 * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent. 438 */ 439 if ((begrun + runlength) > (cmd->data_sn - 1)) { 440 pr_err("Initiator requesting BegRun: 0x%08x, RunLength" 441 ": 0x%08x greater than maximum DataSN: 0x%08x.\n", 442 begrun, runlength, (cmd->data_sn - 1)); 443 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, 444 buf); 445 } 446 447 dr = iscsit_allocate_datain_req(); 448 if (!dr) 449 return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES, 450 buf); 451 452 dr->data_sn = dr->begrun = begrun; 453 dr->runlength = runlength; 454 dr->generate_recovery_values = 1; 455 dr->recovery = DATAIN_WITHIN_COMMAND_RECOVERY; 456 457 iscsit_attach_datain_req(cmd, dr); 458 459 cmd->i_state = ISTATE_SEND_DATAIN; 460 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); 461 462 return 0; 463 } 464 465 int iscsit_handle_recovery_datain_or_r2t( 466 struct iscsi_conn *conn, 467 unsigned char *buf, 468 itt_t init_task_tag, 469 u32 targ_xfer_tag, 470 u32 begrun, 471 u32 runlength) 472 { 473 struct iscsi_cmd *cmd; 474 475 cmd = iscsit_find_cmd_from_itt(conn, init_task_tag); 476 if (!cmd) 477 return 0; 478 479 /* 480 * FIXME: This will not work for bidi commands. 481 */ 482 switch (cmd->data_direction) { 483 case DMA_TO_DEVICE: 484 return iscsit_handle_r2t_snack(cmd, buf, begrun, runlength); 485 case DMA_FROM_DEVICE: 486 return iscsit_handle_recovery_datain(cmd, buf, begrun, 487 runlength); 488 default: 489 pr_err("Unknown cmd->data_direction: 0x%02x\n", 490 cmd->data_direction); 491 return -1; 492 } 493 494 return 0; 495 } 496 497 /* #warning FIXME: Status SNACK needs to be dependent on OPCODE!!! */ 498 int iscsit_handle_status_snack( 499 struct iscsi_conn *conn, 500 itt_t init_task_tag, 501 u32 targ_xfer_tag, 502 u32 begrun, 503 u32 runlength) 504 { 505 struct iscsi_cmd *cmd = NULL; 506 u32 last_statsn; 507 int found_cmd; 508 509 if (!begrun) { 510 begrun = conn->exp_statsn; 511 } else if (conn->exp_statsn > begrun) { 512 pr_err("Got Status SNACK Begrun: 0x%08x, RunLength:" 513 " 0x%08x but already got ExpStatSN: 0x%08x on CID:" 514 " %hu.\n", begrun, runlength, conn->exp_statsn, 515 conn->cid); 516 return 0; 517 } 518 519 last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength); 520 521 while (begrun < last_statsn) { 522 found_cmd = 0; 523 524 spin_lock_bh(&conn->cmd_lock); 525 list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) { 526 if (cmd->stat_sn == begrun) { 527 found_cmd = 1; 528 break; 529 } 530 } 531 spin_unlock_bh(&conn->cmd_lock); 532 533 if (!found_cmd) { 534 pr_err("Unable to find StatSN: 0x%08x for" 535 " a Status SNACK, assuming this was a" 536 " protactic SNACK for an untransmitted" 537 " StatSN, ignoring.\n", begrun); 538 begrun++; 539 continue; 540 } 541 542 spin_lock_bh(&cmd->istate_lock); 543 if (cmd->i_state == ISTATE_SEND_DATAIN) { 544 spin_unlock_bh(&cmd->istate_lock); 545 pr_err("Ignoring Status SNACK for BegRun:" 546 " 0x%08x, RunLength: 0x%08x, assuming this was" 547 " a protactic SNACK for an untransmitted" 548 " StatSN\n", begrun, runlength); 549 begrun++; 550 continue; 551 } 552 spin_unlock_bh(&cmd->istate_lock); 553 554 cmd->i_state = ISTATE_SEND_STATUS_RECOVERY; 555 iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); 556 begrun++; 557 } 558 559 return 0; 560 } 561 562 int iscsit_handle_data_ack( 563 struct iscsi_conn *conn, 564 u32 targ_xfer_tag, 565 u32 begrun, 566 u32 runlength) 567 { 568 struct iscsi_cmd *cmd = NULL; 569 570 cmd = iscsit_find_cmd_from_ttt(conn, targ_xfer_tag); 571 if (!cmd) { 572 pr_err("Data ACK SNACK for TTT: 0x%08x is" 573 " invalid.\n", targ_xfer_tag); 574 return -1; 575 } 576 577 if (begrun <= cmd->acked_data_sn) { 578 pr_err("ITT: 0x%08x Data ACK SNACK BegRUN: 0x%08x is" 579 " less than the already acked DataSN: 0x%08x.\n", 580 cmd->init_task_tag, begrun, cmd->acked_data_sn); 581 return -1; 582 } 583 584 /* 585 * For Data ACK SNACK, BegRun is the next expected DataSN. 586 * (see iSCSI v19: 10.16.6) 587 */ 588 cmd->cmd_flags |= ICF_GOT_DATACK_SNACK; 589 cmd->acked_data_sn = (begrun - 1); 590 591 pr_debug("Received Data ACK SNACK for ITT: 0x%08x," 592 " updated acked DataSN to 0x%08x.\n", 593 cmd->init_task_tag, cmd->acked_data_sn); 594 595 return 0; 596 } 597 598 static int iscsit_send_recovery_r2t( 599 struct iscsi_cmd *cmd, 600 u32 offset, 601 u32 xfer_len) 602 { 603 int ret; 604 605 spin_lock_bh(&cmd->r2t_lock); 606 ret = iscsit_add_r2t_to_list(cmd, offset, xfer_len, 1, 0); 607 spin_unlock_bh(&cmd->r2t_lock); 608 609 return ret; 610 } 611 612 int iscsit_dataout_datapduinorder_no_fbit( 613 struct iscsi_cmd *cmd, 614 struct iscsi_pdu *pdu) 615 { 616 int i, send_recovery_r2t = 0, recovery = 0; 617 u32 length = 0, offset = 0, pdu_count = 0, xfer_len = 0; 618 struct iscsi_conn *conn = cmd->conn; 619 struct iscsi_pdu *first_pdu = NULL; 620 621 /* 622 * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count 623 * of the DataOUT sequence. 624 */ 625 if (conn->sess->sess_ops->DataSequenceInOrder) { 626 for (i = 0; i < cmd->pdu_count; i++) { 627 if (cmd->pdu_list[i].seq_no == pdu->seq_no) { 628 if (!first_pdu) 629 first_pdu = &cmd->pdu_list[i]; 630 xfer_len += cmd->pdu_list[i].length; 631 pdu_count++; 632 } else if (pdu_count) 633 break; 634 } 635 } else { 636 struct iscsi_seq *seq = cmd->seq_ptr; 637 638 first_pdu = &cmd->pdu_list[seq->pdu_start]; 639 pdu_count = seq->pdu_count; 640 } 641 642 if (!first_pdu || !pdu_count) 643 return DATAOUT_CANNOT_RECOVER; 644 645 /* 646 * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu. 647 * The following ugly logic does batching of not received PDUs. 648 */ 649 for (i = 0; i < pdu_count; i++) { 650 if (first_pdu[i].status == ISCSI_PDU_RECEIVED_OK) { 651 if (!send_recovery_r2t) 652 continue; 653 654 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0) 655 return DATAOUT_CANNOT_RECOVER; 656 657 send_recovery_r2t = length = offset = 0; 658 continue; 659 } 660 /* 661 * Set recovery = 1 for any missing, CRC failed, or timed 662 * out PDUs to let the DataOUT logic know that this sequence 663 * has not been completed yet. 664 * 665 * Also, only send a Recovery R2T for ISCSI_PDU_NOT_RECEIVED. 666 * We assume if the PDU either failed CRC or timed out 667 * that a Recovery R2T has already been sent. 668 */ 669 recovery = 1; 670 671 if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED) 672 continue; 673 674 if (!offset) 675 offset = first_pdu[i].offset; 676 length += first_pdu[i].length; 677 678 send_recovery_r2t = 1; 679 } 680 681 if (send_recovery_r2t) 682 if (iscsit_send_recovery_r2t(cmd, offset, length) < 0) 683 return DATAOUT_CANNOT_RECOVER; 684 685 return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY; 686 } 687 688 static int iscsit_recalculate_dataout_values( 689 struct iscsi_cmd *cmd, 690 u32 pdu_offset, 691 u32 pdu_length, 692 u32 *r2t_offset, 693 u32 *r2t_length) 694 { 695 int i; 696 struct iscsi_conn *conn = cmd->conn; 697 struct iscsi_pdu *pdu = NULL; 698 699 if (conn->sess->sess_ops->DataSequenceInOrder) { 700 cmd->data_sn = 0; 701 702 if (conn->sess->sess_ops->DataPDUInOrder) { 703 *r2t_offset = cmd->write_data_done; 704 *r2t_length = (cmd->seq_end_offset - 705 cmd->write_data_done); 706 return 0; 707 } 708 709 *r2t_offset = cmd->seq_start_offset; 710 *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset); 711 712 for (i = 0; i < cmd->pdu_count; i++) { 713 pdu = &cmd->pdu_list[i]; 714 715 if (pdu->status != ISCSI_PDU_RECEIVED_OK) 716 continue; 717 718 if ((pdu->offset >= cmd->seq_start_offset) && 719 ((pdu->offset + pdu->length) <= 720 cmd->seq_end_offset)) { 721 if (!cmd->unsolicited_data) 722 cmd->next_burst_len -= pdu->length; 723 else 724 cmd->first_burst_len -= pdu->length; 725 726 cmd->write_data_done -= pdu->length; 727 pdu->status = ISCSI_PDU_NOT_RECEIVED; 728 } 729 } 730 } else { 731 struct iscsi_seq *seq = NULL; 732 733 seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length); 734 if (!seq) 735 return -1; 736 737 *r2t_offset = seq->orig_offset; 738 *r2t_length = seq->xfer_len; 739 740 cmd->write_data_done -= (seq->offset - seq->orig_offset); 741 if (cmd->immediate_data) 742 cmd->first_burst_len = cmd->write_data_done; 743 744 seq->data_sn = 0; 745 seq->offset = seq->orig_offset; 746 seq->next_burst_len = 0; 747 seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY; 748 749 if (conn->sess->sess_ops->DataPDUInOrder) 750 return 0; 751 752 for (i = 0; i < seq->pdu_count; i++) { 753 pdu = &cmd->pdu_list[i+seq->pdu_start]; 754 755 if (pdu->status != ISCSI_PDU_RECEIVED_OK) 756 continue; 757 758 pdu->status = ISCSI_PDU_NOT_RECEIVED; 759 } 760 } 761 762 return 0; 763 } 764 765 int iscsit_recover_dataout_sequence( 766 struct iscsi_cmd *cmd, 767 u32 pdu_offset, 768 u32 pdu_length) 769 { 770 u32 r2t_length = 0, r2t_offset = 0; 771 772 spin_lock_bh(&cmd->istate_lock); 773 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY; 774 spin_unlock_bh(&cmd->istate_lock); 775 776 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length, 777 &r2t_offset, &r2t_length) < 0) 778 return DATAOUT_CANNOT_RECOVER; 779 780 iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length); 781 782 return DATAOUT_WITHIN_COMMAND_RECOVERY; 783 } 784 785 static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void) 786 { 787 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL; 788 789 ooo_cmdsn = kmem_cache_zalloc(lio_ooo_cache, GFP_ATOMIC); 790 if (!ooo_cmdsn) { 791 pr_err("Unable to allocate memory for" 792 " struct iscsi_ooo_cmdsn.\n"); 793 return NULL; 794 } 795 INIT_LIST_HEAD(&ooo_cmdsn->ooo_list); 796 797 return ooo_cmdsn; 798 } 799 800 /* 801 * Called with sess->cmdsn_mutex held. 802 */ 803 static int iscsit_attach_ooo_cmdsn( 804 struct iscsi_session *sess, 805 struct iscsi_ooo_cmdsn *ooo_cmdsn) 806 { 807 struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp; 808 /* 809 * We attach the struct iscsi_ooo_cmdsn entry to the out of order 810 * list in increasing CmdSN order. 811 * This allows iscsi_execute_ooo_cmdsns() to detect any 812 * additional CmdSN holes while performing delayed execution. 813 */ 814 if (list_empty(&sess->sess_ooo_cmdsn_list)) 815 list_add_tail(&ooo_cmdsn->ooo_list, 816 &sess->sess_ooo_cmdsn_list); 817 else { 818 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev, 819 typeof(*ooo_tail), ooo_list); 820 /* 821 * CmdSN is greater than the tail of the list. 822 */ 823 if (iscsi_sna_lt(ooo_tail->cmdsn, ooo_cmdsn->cmdsn)) 824 list_add_tail(&ooo_cmdsn->ooo_list, 825 &sess->sess_ooo_cmdsn_list); 826 else { 827 /* 828 * CmdSN is either lower than the head, or somewhere 829 * in the middle. 830 */ 831 list_for_each_entry(ooo_tmp, &sess->sess_ooo_cmdsn_list, 832 ooo_list) { 833 if (iscsi_sna_lt(ooo_tmp->cmdsn, ooo_cmdsn->cmdsn)) 834 continue; 835 836 /* Insert before this entry */ 837 list_add(&ooo_cmdsn->ooo_list, 838 ooo_tmp->ooo_list.prev); 839 break; 840 } 841 } 842 } 843 844 return 0; 845 } 846 847 /* 848 * Removes an struct iscsi_ooo_cmdsn from a session's list, 849 * called with struct iscsi_session->cmdsn_mutex held. 850 */ 851 void iscsit_remove_ooo_cmdsn( 852 struct iscsi_session *sess, 853 struct iscsi_ooo_cmdsn *ooo_cmdsn) 854 { 855 list_del(&ooo_cmdsn->ooo_list); 856 kmem_cache_free(lio_ooo_cache, ooo_cmdsn); 857 } 858 859 void iscsit_clear_ooo_cmdsns_for_conn(struct iscsi_conn *conn) 860 { 861 struct iscsi_ooo_cmdsn *ooo_cmdsn; 862 struct iscsi_session *sess = conn->sess; 863 864 mutex_lock(&sess->cmdsn_mutex); 865 list_for_each_entry(ooo_cmdsn, &sess->sess_ooo_cmdsn_list, ooo_list) { 866 if (ooo_cmdsn->cid != conn->cid) 867 continue; 868 869 ooo_cmdsn->cmd = NULL; 870 } 871 mutex_unlock(&sess->cmdsn_mutex); 872 } 873 874 /* 875 * Called with sess->cmdsn_mutex held. 876 */ 877 int iscsit_execute_ooo_cmdsns(struct iscsi_session *sess) 878 { 879 int ooo_count = 0; 880 struct iscsi_cmd *cmd = NULL; 881 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp; 882 883 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp, 884 &sess->sess_ooo_cmdsn_list, ooo_list) { 885 if (ooo_cmdsn->cmdsn != sess->exp_cmd_sn) 886 continue; 887 888 if (!ooo_cmdsn->cmd) { 889 sess->exp_cmd_sn++; 890 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn); 891 continue; 892 } 893 894 cmd = ooo_cmdsn->cmd; 895 cmd->i_state = cmd->deferred_i_state; 896 ooo_count++; 897 sess->exp_cmd_sn++; 898 pr_debug("Executing out of order CmdSN: 0x%08x," 899 " incremented ExpCmdSN to 0x%08x.\n", 900 cmd->cmd_sn, sess->exp_cmd_sn); 901 902 iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn); 903 904 if (iscsit_execute_cmd(cmd, 1) < 0) 905 return -1; 906 907 continue; 908 } 909 910 return ooo_count; 911 } 912 913 /* 914 * Called either: 915 * 916 * 1. With sess->cmdsn_mutex held from iscsi_execute_ooo_cmdsns() 917 * or iscsi_check_received_cmdsn(). 918 * 2. With no locks held directly from iscsi_handle_XXX_pdu() functions 919 * for immediate commands. 920 */ 921 int iscsit_execute_cmd(struct iscsi_cmd *cmd, int ooo) 922 { 923 struct se_cmd *se_cmd = &cmd->se_cmd; 924 struct iscsi_conn *conn = cmd->conn; 925 int lr = 0; 926 927 spin_lock_bh(&cmd->istate_lock); 928 if (ooo) 929 cmd->cmd_flags &= ~ICF_OOO_CMDSN; 930 931 switch (cmd->iscsi_opcode) { 932 case ISCSI_OP_SCSI_CMD: 933 /* 934 * Go ahead and send the CHECK_CONDITION status for 935 * any SCSI CDB exceptions that may have occurred. 936 */ 937 if (cmd->sense_reason) { 938 if (cmd->sense_reason == TCM_RESERVATION_CONFLICT) { 939 cmd->i_state = ISTATE_SEND_STATUS; 940 spin_unlock_bh(&cmd->istate_lock); 941 iscsit_add_cmd_to_response_queue(cmd, cmd->conn, 942 cmd->i_state); 943 return 0; 944 } 945 spin_unlock_bh(&cmd->istate_lock); 946 /* 947 * Determine if delayed TASK_ABORTED status for WRITEs 948 * should be sent now if no unsolicited data out 949 * payloads are expected, or if the delayed status 950 * should be sent after unsolicited data out with 951 * ISCSI_FLAG_CMD_FINAL set in iscsi_handle_data_out() 952 */ 953 if (transport_check_aborted_status(se_cmd, 954 (cmd->unsolicited_data == 0)) != 0) 955 return 0; 956 /* 957 * Otherwise send CHECK_CONDITION and sense for 958 * exception 959 */ 960 return transport_send_check_condition_and_sense(se_cmd, 961 cmd->sense_reason, 0); 962 } 963 /* 964 * Special case for delayed CmdSN with Immediate 965 * Data and/or Unsolicited Data Out attached. 966 */ 967 if (cmd->immediate_data) { 968 if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) { 969 spin_unlock_bh(&cmd->istate_lock); 970 target_execute_cmd(&cmd->se_cmd); 971 return 0; 972 } 973 spin_unlock_bh(&cmd->istate_lock); 974 975 if (!(cmd->cmd_flags & 976 ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) { 977 /* 978 * Send the delayed TASK_ABORTED status for 979 * WRITEs if no more unsolicitied data is 980 * expected. 981 */ 982 if (transport_check_aborted_status(se_cmd, 1) 983 != 0) 984 return 0; 985 986 iscsit_set_dataout_sequence_values(cmd); 987 conn->conn_transport->iscsit_get_dataout(conn, cmd, false); 988 } 989 return 0; 990 } 991 /* 992 * The default handler. 993 */ 994 spin_unlock_bh(&cmd->istate_lock); 995 996 if ((cmd->data_direction == DMA_TO_DEVICE) && 997 !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) { 998 /* 999 * Send the delayed TASK_ABORTED status for WRITEs if 1000 * no more nsolicitied data is expected. 1001 */ 1002 if (transport_check_aborted_status(se_cmd, 1) != 0) 1003 return 0; 1004 1005 iscsit_set_unsoliticed_dataout(cmd); 1006 } 1007 return transport_handle_cdb_direct(&cmd->se_cmd); 1008 1009 case ISCSI_OP_NOOP_OUT: 1010 case ISCSI_OP_TEXT: 1011 spin_unlock_bh(&cmd->istate_lock); 1012 iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state); 1013 break; 1014 case ISCSI_OP_SCSI_TMFUNC: 1015 if (cmd->se_cmd.se_tmr_req->response) { 1016 spin_unlock_bh(&cmd->istate_lock); 1017 iscsit_add_cmd_to_response_queue(cmd, cmd->conn, 1018 cmd->i_state); 1019 return 0; 1020 } 1021 spin_unlock_bh(&cmd->istate_lock); 1022 1023 return transport_generic_handle_tmr(&cmd->se_cmd); 1024 case ISCSI_OP_LOGOUT: 1025 spin_unlock_bh(&cmd->istate_lock); 1026 switch (cmd->logout_reason) { 1027 case ISCSI_LOGOUT_REASON_CLOSE_SESSION: 1028 lr = iscsit_logout_closesession(cmd, cmd->conn); 1029 break; 1030 case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION: 1031 lr = iscsit_logout_closeconnection(cmd, cmd->conn); 1032 break; 1033 case ISCSI_LOGOUT_REASON_RECOVERY: 1034 lr = iscsit_logout_removeconnforrecovery(cmd, cmd->conn); 1035 break; 1036 default: 1037 pr_err("Unknown iSCSI Logout Request Code:" 1038 " 0x%02x\n", cmd->logout_reason); 1039 return -1; 1040 } 1041 1042 return lr; 1043 default: 1044 spin_unlock_bh(&cmd->istate_lock); 1045 pr_err("Cannot perform out of order execution for" 1046 " unknown iSCSI Opcode: 0x%02x\n", cmd->iscsi_opcode); 1047 return -1; 1048 } 1049 1050 return 0; 1051 } 1052 1053 void iscsit_free_all_ooo_cmdsns(struct iscsi_session *sess) 1054 { 1055 struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp; 1056 1057 mutex_lock(&sess->cmdsn_mutex); 1058 list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp, 1059 &sess->sess_ooo_cmdsn_list, ooo_list) { 1060 1061 list_del(&ooo_cmdsn->ooo_list); 1062 kmem_cache_free(lio_ooo_cache, ooo_cmdsn); 1063 } 1064 mutex_unlock(&sess->cmdsn_mutex); 1065 } 1066 1067 int iscsit_handle_ooo_cmdsn( 1068 struct iscsi_session *sess, 1069 struct iscsi_cmd *cmd, 1070 u32 cmdsn) 1071 { 1072 int batch = 0; 1073 struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL; 1074 1075 cmd->deferred_i_state = cmd->i_state; 1076 cmd->i_state = ISTATE_DEFERRED_CMD; 1077 cmd->cmd_flags |= ICF_OOO_CMDSN; 1078 1079 if (list_empty(&sess->sess_ooo_cmdsn_list)) 1080 batch = 1; 1081 else { 1082 ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev, 1083 typeof(*ooo_tail), ooo_list); 1084 if (ooo_tail->cmdsn != (cmdsn - 1)) 1085 batch = 1; 1086 } 1087 1088 ooo_cmdsn = iscsit_allocate_ooo_cmdsn(); 1089 if (!ooo_cmdsn) 1090 return -ENOMEM; 1091 1092 ooo_cmdsn->cmd = cmd; 1093 ooo_cmdsn->batch_count = (batch) ? 1094 (cmdsn - sess->exp_cmd_sn) : 1; 1095 ooo_cmdsn->cid = cmd->conn->cid; 1096 ooo_cmdsn->exp_cmdsn = sess->exp_cmd_sn; 1097 ooo_cmdsn->cmdsn = cmdsn; 1098 1099 if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) { 1100 kmem_cache_free(lio_ooo_cache, ooo_cmdsn); 1101 return -ENOMEM; 1102 } 1103 1104 return 0; 1105 } 1106 1107 static int iscsit_set_dataout_timeout_values( 1108 struct iscsi_cmd *cmd, 1109 u32 *offset, 1110 u32 *length) 1111 { 1112 struct iscsi_conn *conn = cmd->conn; 1113 struct iscsi_r2t *r2t; 1114 1115 if (cmd->unsolicited_data) { 1116 *offset = 0; 1117 *length = (conn->sess->sess_ops->FirstBurstLength > 1118 cmd->se_cmd.data_length) ? 1119 cmd->se_cmd.data_length : 1120 conn->sess->sess_ops->FirstBurstLength; 1121 return 0; 1122 } 1123 1124 spin_lock_bh(&cmd->r2t_lock); 1125 if (list_empty(&cmd->cmd_r2t_list)) { 1126 pr_err("cmd->cmd_r2t_list is empty!\n"); 1127 spin_unlock_bh(&cmd->r2t_lock); 1128 return -1; 1129 } 1130 1131 list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) { 1132 if (r2t->sent_r2t && !r2t->recovery_r2t && !r2t->seq_complete) { 1133 *offset = r2t->offset; 1134 *length = r2t->xfer_len; 1135 spin_unlock_bh(&cmd->r2t_lock); 1136 return 0; 1137 } 1138 } 1139 spin_unlock_bh(&cmd->r2t_lock); 1140 1141 pr_err("Unable to locate any incomplete DataOUT" 1142 " sequences for ITT: 0x%08x.\n", cmd->init_task_tag); 1143 1144 return -1; 1145 } 1146 1147 /* 1148 * NOTE: Called from interrupt (timer) context. 1149 */ 1150 void iscsit_handle_dataout_timeout(struct timer_list *t) 1151 { 1152 u32 pdu_length = 0, pdu_offset = 0; 1153 u32 r2t_length = 0, r2t_offset = 0; 1154 struct iscsi_cmd *cmd = from_timer(cmd, t, dataout_timer); 1155 struct iscsi_conn *conn = cmd->conn; 1156 struct iscsi_session *sess = NULL; 1157 struct iscsi_node_attrib *na; 1158 1159 iscsit_inc_conn_usage_count(conn); 1160 1161 spin_lock_bh(&cmd->dataout_timeout_lock); 1162 if (cmd->dataout_timer_flags & ISCSI_TF_STOP) { 1163 spin_unlock_bh(&cmd->dataout_timeout_lock); 1164 iscsit_dec_conn_usage_count(conn); 1165 return; 1166 } 1167 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING; 1168 sess = conn->sess; 1169 na = iscsit_tpg_get_node_attrib(sess); 1170 1171 if (!sess->sess_ops->ErrorRecoveryLevel) { 1172 pr_debug("Unable to recover from DataOut timeout while" 1173 " in ERL=0.\n"); 1174 goto failure; 1175 } 1176 1177 if (++cmd->dataout_timeout_retries == na->dataout_timeout_retries) { 1178 pr_debug("Command ITT: 0x%08x exceeded max retries" 1179 " for DataOUT timeout %u, closing iSCSI connection.\n", 1180 cmd->init_task_tag, na->dataout_timeout_retries); 1181 goto failure; 1182 } 1183 1184 cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY; 1185 1186 if (conn->sess->sess_ops->DataSequenceInOrder) { 1187 if (conn->sess->sess_ops->DataPDUInOrder) { 1188 pdu_offset = cmd->write_data_done; 1189 if ((pdu_offset + (conn->sess->sess_ops->MaxBurstLength - 1190 cmd->next_burst_len)) > cmd->se_cmd.data_length) 1191 pdu_length = (cmd->se_cmd.data_length - 1192 cmd->write_data_done); 1193 else 1194 pdu_length = (conn->sess->sess_ops->MaxBurstLength - 1195 cmd->next_burst_len); 1196 } else { 1197 pdu_offset = cmd->seq_start_offset; 1198 pdu_length = (cmd->seq_end_offset - 1199 cmd->seq_start_offset); 1200 } 1201 } else { 1202 if (iscsit_set_dataout_timeout_values(cmd, &pdu_offset, 1203 &pdu_length) < 0) 1204 goto failure; 1205 } 1206 1207 if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length, 1208 &r2t_offset, &r2t_length) < 0) 1209 goto failure; 1210 1211 pr_debug("Command ITT: 0x%08x timed out waiting for" 1212 " completion of %sDataOUT Sequence Offset: %u, Length: %u\n", 1213 cmd->init_task_tag, (cmd->unsolicited_data) ? "Unsolicited " : 1214 "", r2t_offset, r2t_length); 1215 1216 if (iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length) < 0) 1217 goto failure; 1218 1219 iscsit_start_dataout_timer(cmd, conn); 1220 spin_unlock_bh(&cmd->dataout_timeout_lock); 1221 iscsit_dec_conn_usage_count(conn); 1222 1223 return; 1224 1225 failure: 1226 spin_unlock_bh(&cmd->dataout_timeout_lock); 1227 iscsit_cause_connection_reinstatement(conn, 0); 1228 iscsit_dec_conn_usage_count(conn); 1229 } 1230 1231 void iscsit_mod_dataout_timer(struct iscsi_cmd *cmd) 1232 { 1233 struct iscsi_conn *conn = cmd->conn; 1234 struct iscsi_session *sess = conn->sess; 1235 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess); 1236 1237 spin_lock_bh(&cmd->dataout_timeout_lock); 1238 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) { 1239 spin_unlock_bh(&cmd->dataout_timeout_lock); 1240 return; 1241 } 1242 1243 mod_timer(&cmd->dataout_timer, 1244 (get_jiffies_64() + na->dataout_timeout * HZ)); 1245 pr_debug("Updated DataOUT timer for ITT: 0x%08x", 1246 cmd->init_task_tag); 1247 spin_unlock_bh(&cmd->dataout_timeout_lock); 1248 } 1249 1250 /* 1251 * Called with cmd->dataout_timeout_lock held. 1252 */ 1253 void iscsit_start_dataout_timer( 1254 struct iscsi_cmd *cmd, 1255 struct iscsi_conn *conn) 1256 { 1257 struct iscsi_session *sess = conn->sess; 1258 struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess); 1259 1260 if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING) 1261 return; 1262 1263 pr_debug("Starting DataOUT timer for ITT: 0x%08x on" 1264 " CID: %hu.\n", cmd->init_task_tag, conn->cid); 1265 1266 cmd->dataout_timer_flags &= ~ISCSI_TF_STOP; 1267 cmd->dataout_timer_flags |= ISCSI_TF_RUNNING; 1268 mod_timer(&cmd->dataout_timer, jiffies + na->dataout_timeout * HZ); 1269 } 1270 1271 void iscsit_stop_dataout_timer(struct iscsi_cmd *cmd) 1272 { 1273 spin_lock_bh(&cmd->dataout_timeout_lock); 1274 if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) { 1275 spin_unlock_bh(&cmd->dataout_timeout_lock); 1276 return; 1277 } 1278 cmd->dataout_timer_flags |= ISCSI_TF_STOP; 1279 spin_unlock_bh(&cmd->dataout_timeout_lock); 1280 1281 del_timer_sync(&cmd->dataout_timer); 1282 1283 spin_lock_bh(&cmd->dataout_timeout_lock); 1284 cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING; 1285 pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n", 1286 cmd->init_task_tag); 1287 spin_unlock_bh(&cmd->dataout_timeout_lock); 1288 } 1289 EXPORT_SYMBOL(iscsit_stop_dataout_timer); 1290