1 /* 2 * iSCSI Initiator over iSER Data-Path 3 * 4 * Copyright (C) 2004 Dmitry Yusupov 5 * Copyright (C) 2004 Alex Aizman 6 * Copyright (C) 2005 Mike Christie 7 * Copyright (c) 2005, 2006 Voltaire, Inc. All rights reserved. 8 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved. 9 * maintained by openib-general@openib.org 10 * 11 * This software is available to you under a choice of one of two 12 * licenses. You may choose to be licensed under the terms of the GNU 13 * General Public License (GPL) Version 2, available from the file 14 * COPYING in the main directory of this source tree, or the 15 * OpenIB.org BSD license below: 16 * 17 * Redistribution and use in source and binary forms, with or 18 * without modification, are permitted provided that the following 19 * conditions are met: 20 * 21 * - Redistributions of source code must retain the above 22 * copyright notice, this list of conditions and the following 23 * disclaimer. 24 * 25 * - Redistributions in binary form must reproduce the above 26 * copyright notice, this list of conditions and the following 27 * disclaimer in the documentation and/or other materials 28 * provided with the distribution. 29 * 30 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 31 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 32 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 33 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 34 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 35 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 36 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 37 * SOFTWARE. 38 * 39 * Credits: 40 * Christoph Hellwig 41 * FUJITA Tomonori 42 * Arne Redlich 43 * Zhenyu Wang 44 * Modified by: 45 * Erez Zilber 46 */ 47 48 #include <linux/types.h> 49 #include <linux/list.h> 50 #include <linux/hardirq.h> 51 #include <linux/kfifo.h> 52 #include <linux/blkdev.h> 53 #include <linux/init.h> 54 #include <linux/ioctl.h> 55 #include <linux/cdev.h> 56 #include <linux/in.h> 57 #include <linux/net.h> 58 #include <linux/scatterlist.h> 59 #include <linux/delay.h> 60 #include <linux/slab.h> 61 #include <linux/module.h> 62 63 #include <net/sock.h> 64 65 #include <linux/uaccess.h> 66 67 #include <scsi/scsi_cmnd.h> 68 #include <scsi/scsi_device.h> 69 #include <scsi/scsi_eh.h> 70 #include <scsi/scsi_tcq.h> 71 #include <scsi/scsi_host.h> 72 #include <scsi/scsi.h> 73 #include <scsi/scsi_transport_iscsi.h> 74 75 #include "iscsi_iser.h" 76 77 MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover"); 78 MODULE_LICENSE("Dual BSD/GPL"); 79 MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz"); 80 81 static struct scsi_host_template iscsi_iser_sht; 82 static struct iscsi_transport iscsi_iser_transport; 83 static struct scsi_transport_template *iscsi_iser_scsi_transport; 84 static struct workqueue_struct *release_wq; 85 static DEFINE_MUTEX(unbind_iser_conn_mutex); 86 struct iser_global ig; 87 88 int iser_debug_level = 0; 89 module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR); 90 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)"); 91 92 static unsigned int iscsi_max_lun = 512; 93 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO); 94 MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session (default:512"); 95 96 unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS; 97 module_param_named(max_sectors, iser_max_sectors, uint, S_IRUGO | S_IWUSR); 98 MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command (default:1024"); 99 100 bool iser_always_reg = true; 101 module_param_named(always_register, iser_always_reg, bool, S_IRUGO); 102 MODULE_PARM_DESC(always_register, 103 "Always register memory, even for continuous memory regions (default:true)"); 104 105 bool iser_pi_enable = false; 106 module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO); 107 MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)"); 108 109 int iser_pi_guard; 110 module_param_named(pi_guard, iser_pi_guard, int, S_IRUGO); 111 MODULE_PARM_DESC(pi_guard, "T10-PI guard_type [deprecated]"); 112 113 /* 114 * iscsi_iser_recv() - Process a successful recv completion 115 * @conn: iscsi connection 116 * @hdr: iscsi header 117 * @rx_data: buffer containing receive data payload 118 * @rx_data_len: length of rx_data 119 * 120 * Notes: In case of data length errors or iscsi PDU completion failures 121 * this routine will signal iscsi layer of connection failure. 122 */ 123 void 124 iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr, 125 char *rx_data, int rx_data_len) 126 { 127 int rc = 0; 128 int datalen; 129 130 /* verify PDU length */ 131 datalen = ntoh24(hdr->dlength); 132 if (datalen > rx_data_len || (datalen + 4) < rx_data_len) { 133 iser_err("wrong datalen %d (hdr), %d (IB)\n", 134 datalen, rx_data_len); 135 rc = ISCSI_ERR_DATALEN; 136 goto error; 137 } 138 139 if (datalen != rx_data_len) 140 iser_dbg("aligned datalen (%d) hdr, %d (IB)\n", 141 datalen, rx_data_len); 142 143 rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len); 144 if (rc && rc != ISCSI_ERR_NO_SCSI_CMD) 145 goto error; 146 147 return; 148 error: 149 iscsi_conn_failure(conn, rc); 150 } 151 152 /** 153 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU 154 * @task: iscsi task 155 * @opcode: iscsi command opcode 156 * 157 * Netes: This routine can't fail, just assign iscsi task 158 * hdr and max hdr size. 159 */ 160 static int 161 iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 162 { 163 struct iscsi_iser_task *iser_task = task->dd_data; 164 165 task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header; 166 task->hdr_max = sizeof(iser_task->desc.iscsi_header); 167 168 return 0; 169 } 170 171 /** 172 * iser_initialize_task_headers() - Initialize task headers 173 * @task: iscsi task 174 * @tx_desc: iser tx descriptor 175 * 176 * Notes: 177 * This routine may race with iser teardown flow for scsi 178 * error handling TMFs. So for TMF we should acquire the 179 * state mutex to avoid dereferencing the IB device which 180 * may have already been terminated. 181 */ 182 int 183 iser_initialize_task_headers(struct iscsi_task *task, 184 struct iser_tx_desc *tx_desc) 185 { 186 struct iser_conn *iser_conn = task->conn->dd_data; 187 struct iser_device *device = iser_conn->ib_conn.device; 188 struct iscsi_iser_task *iser_task = task->dd_data; 189 u64 dma_addr; 190 const bool mgmt_task = !task->sc && !in_interrupt(); 191 int ret = 0; 192 193 if (unlikely(mgmt_task)) 194 mutex_lock(&iser_conn->state_mutex); 195 196 if (unlikely(iser_conn->state != ISER_CONN_UP)) { 197 ret = -ENODEV; 198 goto out; 199 } 200 201 dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc, 202 ISER_HEADERS_LEN, DMA_TO_DEVICE); 203 if (ib_dma_mapping_error(device->ib_device, dma_addr)) { 204 ret = -ENOMEM; 205 goto out; 206 } 207 208 tx_desc->wr_idx = 0; 209 tx_desc->mapped = true; 210 tx_desc->dma_addr = dma_addr; 211 tx_desc->tx_sg[0].addr = tx_desc->dma_addr; 212 tx_desc->tx_sg[0].length = ISER_HEADERS_LEN; 213 tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey; 214 215 iser_task->iser_conn = iser_conn; 216 out: 217 if (unlikely(mgmt_task)) 218 mutex_unlock(&iser_conn->state_mutex); 219 220 return ret; 221 } 222 223 /** 224 * iscsi_iser_task_init() - Initialize iscsi-iser task 225 * @task: iscsi task 226 * 227 * Initialize the task for the scsi command or mgmt command. 228 * 229 * Return: Returns zero on success or -ENOMEM when failing 230 * to init task headers (dma mapping error). 231 */ 232 static int 233 iscsi_iser_task_init(struct iscsi_task *task) 234 { 235 struct iscsi_iser_task *iser_task = task->dd_data; 236 int ret; 237 238 ret = iser_initialize_task_headers(task, &iser_task->desc); 239 if (ret) { 240 iser_err("Failed to init task %p, err = %d\n", 241 iser_task, ret); 242 return ret; 243 } 244 245 /* mgmt task */ 246 if (!task->sc) 247 return 0; 248 249 iser_task->command_sent = 0; 250 iser_task_rdma_init(iser_task); 251 iser_task->sc = task->sc; 252 253 return 0; 254 } 255 256 /** 257 * iscsi_iser_mtask_xmit() - xmit management (immediate) task 258 * @conn: iscsi connection 259 * @task: task management task 260 * 261 * Notes: 262 * The function can return -EAGAIN in which case caller must 263 * call it again later, or recover. '0' return code means successful 264 * xmit. 265 * 266 **/ 267 static int 268 iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task) 269 { 270 int error = 0; 271 272 iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt); 273 274 error = iser_send_control(conn, task); 275 276 /* since iser xmits control with zero copy, tasks can not be recycled 277 * right after sending them. 278 * The recycling scheme is based on whether a response is expected 279 * - if yes, the task is recycled at iscsi_complete_pdu 280 * - if no, the task is recycled at iser_snd_completion 281 */ 282 return error; 283 } 284 285 static int 286 iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn, 287 struct iscsi_task *task) 288 { 289 struct iscsi_r2t_info *r2t = &task->unsol_r2t; 290 struct iscsi_data hdr; 291 int error = 0; 292 293 /* Send data-out PDUs while there's still unsolicited data to send */ 294 while (iscsi_task_has_unsol_data(task)) { 295 iscsi_prep_data_out_pdu(task, r2t, &hdr); 296 iser_dbg("Sending data-out: itt 0x%x, data count %d\n", 297 hdr.itt, r2t->data_count); 298 299 /* the buffer description has been passed with the command */ 300 /* Send the command */ 301 error = iser_send_data_out(conn, task, &hdr); 302 if (error) { 303 r2t->datasn--; 304 goto iscsi_iser_task_xmit_unsol_data_exit; 305 } 306 r2t->sent += r2t->data_count; 307 iser_dbg("Need to send %d more as data-out PDUs\n", 308 r2t->data_length - r2t->sent); 309 } 310 311 iscsi_iser_task_xmit_unsol_data_exit: 312 return error; 313 } 314 315 /** 316 * iscsi_iser_task_xmit() - xmit iscsi-iser task 317 * @task: iscsi task 318 * 319 * Return: zero on success or escalates $error on failure. 320 */ 321 static int 322 iscsi_iser_task_xmit(struct iscsi_task *task) 323 { 324 struct iscsi_conn *conn = task->conn; 325 struct iscsi_iser_task *iser_task = task->dd_data; 326 int error = 0; 327 328 if (!task->sc) 329 return iscsi_iser_mtask_xmit(conn, task); 330 331 if (task->sc->sc_data_direction == DMA_TO_DEVICE) { 332 BUG_ON(scsi_bufflen(task->sc) == 0); 333 334 iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n", 335 task->itt, scsi_bufflen(task->sc), 336 task->imm_count, task->unsol_r2t.data_length); 337 } 338 339 iser_dbg("ctask xmit [cid %d itt 0x%x]\n", 340 conn->id, task->itt); 341 342 /* Send the cmd PDU */ 343 if (!iser_task->command_sent) { 344 error = iser_send_command(conn, task); 345 if (error) 346 goto iscsi_iser_task_xmit_exit; 347 iser_task->command_sent = 1; 348 } 349 350 /* Send unsolicited data-out PDU(s) if necessary */ 351 if (iscsi_task_has_unsol_data(task)) 352 error = iscsi_iser_task_xmit_unsol_data(conn, task); 353 354 iscsi_iser_task_xmit_exit: 355 return error; 356 } 357 358 /** 359 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task 360 * @task: iscsi task 361 * 362 * Notes: In case the RDMA device is already NULL (might have 363 * been removed in DEVICE_REMOVAL CM event it will bail-out 364 * without doing dma unmapping. 365 */ 366 static void iscsi_iser_cleanup_task(struct iscsi_task *task) 367 { 368 struct iscsi_iser_task *iser_task = task->dd_data; 369 struct iser_tx_desc *tx_desc = &iser_task->desc; 370 struct iser_conn *iser_conn = task->conn->dd_data; 371 struct iser_device *device = iser_conn->ib_conn.device; 372 373 /* DEVICE_REMOVAL event might have already released the device */ 374 if (!device) 375 return; 376 377 if (likely(tx_desc->mapped)) { 378 ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr, 379 ISER_HEADERS_LEN, DMA_TO_DEVICE); 380 tx_desc->mapped = false; 381 } 382 383 /* mgmt tasks do not need special cleanup */ 384 if (!task->sc) 385 return; 386 387 if (iser_task->status == ISER_TASK_STATUS_STARTED) { 388 iser_task->status = ISER_TASK_STATUS_COMPLETED; 389 iser_task_rdma_finalize(iser_task); 390 } 391 } 392 393 /** 394 * iscsi_iser_check_protection() - check protection information status of task. 395 * @task: iscsi task 396 * @sector: error sector if exsists (output) 397 * 398 * Return: zero if no data-integrity errors have occured 399 * 0x1: data-integrity error occured in the guard-block 400 * 0x2: data-integrity error occured in the reference tag 401 * 0x3: data-integrity error occured in the application tag 402 * 403 * In addition the error sector is marked. 404 */ 405 static u8 406 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector) 407 { 408 struct iscsi_iser_task *iser_task = task->dd_data; 409 410 if (iser_task->dir[ISER_DIR_IN]) 411 return iser_check_task_pi_status(iser_task, ISER_DIR_IN, 412 sector); 413 else 414 return iser_check_task_pi_status(iser_task, ISER_DIR_OUT, 415 sector); 416 } 417 418 /** 419 * iscsi_iser_conn_create() - create a new iscsi-iser connection 420 * @cls_session: iscsi class connection 421 * @conn_idx: connection index within the session (for MCS) 422 * 423 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL 424 * otherwise. 425 */ 426 static struct iscsi_cls_conn * 427 iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, 428 uint32_t conn_idx) 429 { 430 struct iscsi_conn *conn; 431 struct iscsi_cls_conn *cls_conn; 432 433 cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx); 434 if (!cls_conn) 435 return NULL; 436 conn = cls_conn->dd_data; 437 438 /* 439 * due to issues with the login code re iser sematics 440 * this not set in iscsi_conn_setup - FIXME 441 */ 442 conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN; 443 444 return cls_conn; 445 } 446 447 /** 448 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures 449 * @cls_session: iscsi class session 450 * @cls_conn: iscsi class connection 451 * @transport_eph: transport end-point handle 452 * @is_leading: indicate if this is the session leading connection (MCS) 453 * 454 * Return: zero on success, $error if iscsi_conn_bind fails and 455 * -EINVAL in case end-point doesn't exsits anymore or iser connection 456 * state is not UP (teardown already started). 457 */ 458 static int 459 iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session, 460 struct iscsi_cls_conn *cls_conn, 461 uint64_t transport_eph, 462 int is_leading) 463 { 464 struct iscsi_conn *conn = cls_conn->dd_data; 465 struct iser_conn *iser_conn; 466 struct iscsi_endpoint *ep; 467 int error; 468 469 error = iscsi_conn_bind(cls_session, cls_conn, is_leading); 470 if (error) 471 return error; 472 473 /* the transport ep handle comes from user space so it must be 474 * verified against the global ib connections list */ 475 ep = iscsi_lookup_endpoint(transport_eph); 476 if (!ep) { 477 iser_err("can't bind eph %llx\n", 478 (unsigned long long)transport_eph); 479 return -EINVAL; 480 } 481 iser_conn = ep->dd_data; 482 483 mutex_lock(&iser_conn->state_mutex); 484 if (iser_conn->state != ISER_CONN_UP) { 485 error = -EINVAL; 486 iser_err("iser_conn %p state is %d, teardown started\n", 487 iser_conn, iser_conn->state); 488 goto out; 489 } 490 491 error = iser_alloc_rx_descriptors(iser_conn, conn->session); 492 if (error) 493 goto out; 494 495 /* binds the iSER connection retrieved from the previously 496 * connected ep_handle to the iSCSI layer connection. exchanges 497 * connection pointers */ 498 iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn); 499 500 conn->dd_data = iser_conn; 501 iser_conn->iscsi_conn = conn; 502 503 out: 504 mutex_unlock(&iser_conn->state_mutex); 505 return error; 506 } 507 508 /** 509 * iscsi_iser_conn_start() - start iscsi-iser connection 510 * @cls_conn: iscsi class connection 511 * 512 * Notes: Here iser intialize (or re-initialize) stop_completion as 513 * from this point iscsi must call conn_stop in session/connection 514 * teardown so iser transport must wait for it. 515 */ 516 static int 517 iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn) 518 { 519 struct iscsi_conn *iscsi_conn; 520 struct iser_conn *iser_conn; 521 522 iscsi_conn = cls_conn->dd_data; 523 iser_conn = iscsi_conn->dd_data; 524 reinit_completion(&iser_conn->stop_completion); 525 526 return iscsi_conn_start(cls_conn); 527 } 528 529 /** 530 * iscsi_iser_conn_stop() - stop iscsi-iser connection 531 * @cls_conn: iscsi class connection 532 * @flag: indicate if recover or terminate (passed as is) 533 * 534 * Notes: Calling iscsi_conn_stop might theoretically race with 535 * DEVICE_REMOVAL event and dereference a previously freed RDMA device 536 * handle, so we call it under iser the state lock to protect against 537 * this kind of race. 538 */ 539 static void 540 iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 541 { 542 struct iscsi_conn *conn = cls_conn->dd_data; 543 struct iser_conn *iser_conn = conn->dd_data; 544 545 iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn); 546 547 /* 548 * Userspace may have goofed up and not bound the connection or 549 * might have only partially setup the connection. 550 */ 551 if (iser_conn) { 552 mutex_lock(&iser_conn->state_mutex); 553 mutex_lock(&unbind_iser_conn_mutex); 554 iser_conn_terminate(iser_conn); 555 iscsi_conn_stop(cls_conn, flag); 556 557 /* unbind */ 558 iser_conn->iscsi_conn = NULL; 559 conn->dd_data = NULL; 560 mutex_unlock(&unbind_iser_conn_mutex); 561 562 complete(&iser_conn->stop_completion); 563 mutex_unlock(&iser_conn->state_mutex); 564 } else { 565 iscsi_conn_stop(cls_conn, flag); 566 } 567 } 568 569 /** 570 * iscsi_iser_session_destroy() - destroy iscsi-iser session 571 * @cls_session: iscsi class session 572 * 573 * Removes and free iscsi host. 574 */ 575 static void 576 iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session) 577 { 578 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 579 580 iscsi_session_teardown(cls_session); 581 iscsi_host_remove(shost); 582 iscsi_host_free(shost); 583 } 584 585 static inline unsigned int 586 iser_dif_prot_caps(int prot_caps) 587 { 588 return ((prot_caps & IB_PROT_T10DIF_TYPE_1) ? 589 SHOST_DIF_TYPE1_PROTECTION | SHOST_DIX_TYPE0_PROTECTION | 590 SHOST_DIX_TYPE1_PROTECTION : 0) | 591 ((prot_caps & IB_PROT_T10DIF_TYPE_2) ? 592 SHOST_DIF_TYPE2_PROTECTION | SHOST_DIX_TYPE2_PROTECTION : 0) | 593 ((prot_caps & IB_PROT_T10DIF_TYPE_3) ? 594 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE3_PROTECTION : 0); 595 } 596 597 /** 598 * iscsi_iser_session_create() - create an iscsi-iser session 599 * @ep: iscsi end-point handle 600 * @cmds_max: maximum commands in this session 601 * @qdepth: session command queue depth 602 * @initial_cmdsn: initiator command sequnce number 603 * 604 * Allocates and adds a scsi host, expose DIF supprot if 605 * exists, and sets up an iscsi session. 606 */ 607 static struct iscsi_cls_session * 608 iscsi_iser_session_create(struct iscsi_endpoint *ep, 609 uint16_t cmds_max, uint16_t qdepth, 610 uint32_t initial_cmdsn) 611 { 612 struct iscsi_cls_session *cls_session; 613 struct Scsi_Host *shost; 614 struct iser_conn *iser_conn = NULL; 615 struct ib_conn *ib_conn; 616 u32 max_fr_sectors; 617 618 shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0); 619 if (!shost) 620 return NULL; 621 shost->transportt = iscsi_iser_scsi_transport; 622 shost->cmd_per_lun = qdepth; 623 shost->max_lun = iscsi_max_lun; 624 shost->max_id = 0; 625 shost->max_channel = 0; 626 shost->max_cmd_len = 16; 627 628 /* 629 * older userspace tools (before 2.0-870) did not pass us 630 * the leading conn's ep so this will be NULL; 631 */ 632 if (ep) { 633 iser_conn = ep->dd_data; 634 shost->sg_tablesize = iser_conn->scsi_sg_tablesize; 635 shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds); 636 637 mutex_lock(&iser_conn->state_mutex); 638 if (iser_conn->state != ISER_CONN_UP) { 639 iser_err("iser conn %p already started teardown\n", 640 iser_conn); 641 mutex_unlock(&iser_conn->state_mutex); 642 goto free_host; 643 } 644 645 ib_conn = &iser_conn->ib_conn; 646 if (ib_conn->pi_support) { 647 u32 sig_caps = ib_conn->device->ib_device->attrs.sig_prot_cap; 648 649 scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps)); 650 scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP | 651 SHOST_DIX_GUARD_CRC); 652 } 653 654 if (iscsi_host_add(shost, 655 ib_conn->device->ib_device->dev.parent)) { 656 mutex_unlock(&iser_conn->state_mutex); 657 goto free_host; 658 } 659 mutex_unlock(&iser_conn->state_mutex); 660 } else { 661 shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX); 662 if (iscsi_host_add(shost, NULL)) 663 goto free_host; 664 } 665 666 max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9; 667 shost->max_sectors = min(iser_max_sectors, max_fr_sectors); 668 669 iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n", 670 iser_conn, shost->sg_tablesize, 671 shost->max_sectors); 672 673 if (shost->max_sectors < iser_max_sectors) 674 iser_warn("max_sectors was reduced from %u to %u\n", 675 iser_max_sectors, shost->max_sectors); 676 677 cls_session = iscsi_session_setup(&iscsi_iser_transport, shost, 678 shost->can_queue, 0, 679 sizeof(struct iscsi_iser_task), 680 initial_cmdsn, 0); 681 if (!cls_session) 682 goto remove_host; 683 684 return cls_session; 685 686 remove_host: 687 iscsi_host_remove(shost); 688 free_host: 689 iscsi_host_free(shost); 690 return NULL; 691 } 692 693 static int 694 iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn, 695 enum iscsi_param param, char *buf, int buflen) 696 { 697 int value; 698 699 switch (param) { 700 case ISCSI_PARAM_MAX_RECV_DLENGTH: 701 /* TBD */ 702 break; 703 case ISCSI_PARAM_HDRDGST_EN: 704 sscanf(buf, "%d", &value); 705 if (value) { 706 iser_err("DataDigest wasn't negotiated to None\n"); 707 return -EPROTO; 708 } 709 break; 710 case ISCSI_PARAM_DATADGST_EN: 711 sscanf(buf, "%d", &value); 712 if (value) { 713 iser_err("DataDigest wasn't negotiated to None\n"); 714 return -EPROTO; 715 } 716 break; 717 case ISCSI_PARAM_IFMARKER_EN: 718 sscanf(buf, "%d", &value); 719 if (value) { 720 iser_err("IFMarker wasn't negotiated to No\n"); 721 return -EPROTO; 722 } 723 break; 724 case ISCSI_PARAM_OFMARKER_EN: 725 sscanf(buf, "%d", &value); 726 if (value) { 727 iser_err("OFMarker wasn't negotiated to No\n"); 728 return -EPROTO; 729 } 730 break; 731 default: 732 return iscsi_set_param(cls_conn, param, buf, buflen); 733 } 734 735 return 0; 736 } 737 738 /** 739 * iscsi_iser_set_param() - set class connection parameter 740 * @cls_conn: iscsi class connection 741 * @stats: iscsi stats to output 742 * 743 * Output connection statistics. 744 */ 745 static void 746 iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats) 747 { 748 struct iscsi_conn *conn = cls_conn->dd_data; 749 750 stats->txdata_octets = conn->txdata_octets; 751 stats->rxdata_octets = conn->rxdata_octets; 752 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt; 753 stats->dataout_pdus = conn->dataout_pdus_cnt; 754 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt; 755 stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */ 756 stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */ 757 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt; 758 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt; 759 stats->custom_length = 0; 760 } 761 762 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep, 763 enum iscsi_param param, char *buf) 764 { 765 struct iser_conn *iser_conn = ep->dd_data; 766 767 switch (param) { 768 case ISCSI_PARAM_CONN_PORT: 769 case ISCSI_PARAM_CONN_ADDRESS: 770 if (!iser_conn || !iser_conn->ib_conn.cma_id) 771 return -ENOTCONN; 772 773 return iscsi_conn_get_addr_param((struct sockaddr_storage *) 774 &iser_conn->ib_conn.cma_id->route.addr.dst_addr, 775 param, buf); 776 default: 777 break; 778 } 779 return -ENOSYS; 780 } 781 782 /** 783 * iscsi_iser_ep_connect() - Initiate iSER connection establishment 784 * @shost: scsi_host 785 * @dst_addr: destination address 786 * @non-blocking: indicate if routine can block 787 * 788 * Allocate an iscsi endpoint, an iser_conn structure and bind them. 789 * After that start RDMA connection establishment via rdma_cm. We 790 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown 791 * the endpoint will be destroyed at ep_disconnect while iser_conn will 792 * cleanup its resources asynchronuously. 793 * 794 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error) 795 * if fails. 796 */ 797 static struct iscsi_endpoint * 798 iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr, 799 int non_blocking) 800 { 801 int err; 802 struct iser_conn *iser_conn; 803 struct iscsi_endpoint *ep; 804 805 ep = iscsi_create_endpoint(0); 806 if (!ep) 807 return ERR_PTR(-ENOMEM); 808 809 iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL); 810 if (!iser_conn) { 811 err = -ENOMEM; 812 goto failure; 813 } 814 815 ep->dd_data = iser_conn; 816 iser_conn->ep = ep; 817 iser_conn_init(iser_conn); 818 819 err = iser_connect(iser_conn, NULL, dst_addr, non_blocking); 820 if (err) 821 goto failure; 822 823 return ep; 824 failure: 825 iscsi_destroy_endpoint(ep); 826 return ERR_PTR(err); 827 } 828 829 /** 830 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete 831 * @ep: iscsi endpoint (created at ep_connect) 832 * @timeout_ms: polling timeout allowed in ms. 833 * 834 * This routine boils down to waiting for up_completion signaling 835 * that cma_id got CONNECTED event. 836 * 837 * Return: 1 if succeeded in connection establishment, 0 if timeout expired 838 * (libiscsi will retry will kick in) or -1 if interrupted by signal 839 * or more likely iser connection state transitioned to TEMINATING or 840 * DOWN during the wait period. 841 */ 842 static int 843 iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms) 844 { 845 struct iser_conn *iser_conn = ep->dd_data; 846 int rc; 847 848 rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion, 849 msecs_to_jiffies(timeout_ms)); 850 /* if conn establishment failed, return error code to iscsi */ 851 if (rc == 0) { 852 mutex_lock(&iser_conn->state_mutex); 853 if (iser_conn->state == ISER_CONN_TERMINATING || 854 iser_conn->state == ISER_CONN_DOWN) 855 rc = -1; 856 mutex_unlock(&iser_conn->state_mutex); 857 } 858 859 iser_info("iser conn %p rc = %d\n", iser_conn, rc); 860 861 if (rc > 0) 862 return 1; /* success, this is the equivalent of EPOLLOUT */ 863 else if (!rc) 864 return 0; /* timeout */ 865 else 866 return rc; /* signal */ 867 } 868 869 /** 870 * iscsi_iser_ep_disconnect() - Initiate connection teardown process 871 * @ep: iscsi endpoint handle 872 * 873 * This routine is not blocked by iser and RDMA termination process 874 * completion as we queue a deffered work for iser/RDMA destruction 875 * and cleanup or actually call it immediately in case we didn't pass 876 * iscsi conn bind/start stage, thus it is safe. 877 */ 878 static void 879 iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep) 880 { 881 struct iser_conn *iser_conn = ep->dd_data; 882 883 iser_info("ep %p iser conn %p\n", ep, iser_conn); 884 885 mutex_lock(&iser_conn->state_mutex); 886 iser_conn_terminate(iser_conn); 887 888 /* 889 * if iser_conn and iscsi_conn are bound, we must wait for 890 * iscsi_conn_stop and flush errors completion before freeing 891 * the iser resources. Otherwise we are safe to free resources 892 * immediately. 893 */ 894 if (iser_conn->iscsi_conn) { 895 INIT_WORK(&iser_conn->release_work, iser_release_work); 896 queue_work(release_wq, &iser_conn->release_work); 897 mutex_unlock(&iser_conn->state_mutex); 898 } else { 899 iser_conn->state = ISER_CONN_DOWN; 900 mutex_unlock(&iser_conn->state_mutex); 901 iser_conn_release(iser_conn); 902 } 903 904 iscsi_destroy_endpoint(ep); 905 } 906 907 static umode_t iser_attr_is_visible(int param_type, int param) 908 { 909 switch (param_type) { 910 case ISCSI_HOST_PARAM: 911 switch (param) { 912 case ISCSI_HOST_PARAM_NETDEV_NAME: 913 case ISCSI_HOST_PARAM_HWADDRESS: 914 case ISCSI_HOST_PARAM_INITIATOR_NAME: 915 return S_IRUGO; 916 default: 917 return 0; 918 } 919 case ISCSI_PARAM: 920 switch (param) { 921 case ISCSI_PARAM_MAX_RECV_DLENGTH: 922 case ISCSI_PARAM_MAX_XMIT_DLENGTH: 923 case ISCSI_PARAM_HDRDGST_EN: 924 case ISCSI_PARAM_DATADGST_EN: 925 case ISCSI_PARAM_CONN_ADDRESS: 926 case ISCSI_PARAM_CONN_PORT: 927 case ISCSI_PARAM_EXP_STATSN: 928 case ISCSI_PARAM_PERSISTENT_ADDRESS: 929 case ISCSI_PARAM_PERSISTENT_PORT: 930 case ISCSI_PARAM_PING_TMO: 931 case ISCSI_PARAM_RECV_TMO: 932 case ISCSI_PARAM_INITIAL_R2T_EN: 933 case ISCSI_PARAM_MAX_R2T: 934 case ISCSI_PARAM_IMM_DATA_EN: 935 case ISCSI_PARAM_FIRST_BURST: 936 case ISCSI_PARAM_MAX_BURST: 937 case ISCSI_PARAM_PDU_INORDER_EN: 938 case ISCSI_PARAM_DATASEQ_INORDER_EN: 939 case ISCSI_PARAM_TARGET_NAME: 940 case ISCSI_PARAM_TPGT: 941 case ISCSI_PARAM_USERNAME: 942 case ISCSI_PARAM_PASSWORD: 943 case ISCSI_PARAM_USERNAME_IN: 944 case ISCSI_PARAM_PASSWORD_IN: 945 case ISCSI_PARAM_FAST_ABORT: 946 case ISCSI_PARAM_ABORT_TMO: 947 case ISCSI_PARAM_LU_RESET_TMO: 948 case ISCSI_PARAM_TGT_RESET_TMO: 949 case ISCSI_PARAM_IFACE_NAME: 950 case ISCSI_PARAM_INITIATOR_NAME: 951 case ISCSI_PARAM_DISCOVERY_SESS: 952 return S_IRUGO; 953 default: 954 return 0; 955 } 956 } 957 958 return 0; 959 } 960 961 static int iscsi_iser_slave_alloc(struct scsi_device *sdev) 962 { 963 struct iscsi_session *session; 964 struct iser_conn *iser_conn; 965 struct ib_device *ib_dev; 966 967 mutex_lock(&unbind_iser_conn_mutex); 968 969 session = starget_to_session(scsi_target(sdev))->dd_data; 970 iser_conn = session->leadconn->dd_data; 971 if (!iser_conn) { 972 mutex_unlock(&unbind_iser_conn_mutex); 973 return -ENOTCONN; 974 } 975 ib_dev = iser_conn->ib_conn.device->ib_device; 976 977 if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)) 978 blk_queue_virt_boundary(sdev->request_queue, ~MASK_4K); 979 980 mutex_unlock(&unbind_iser_conn_mutex); 981 982 return 0; 983 } 984 985 static struct scsi_host_template iscsi_iser_sht = { 986 .module = THIS_MODULE, 987 .name = "iSCSI Initiator over iSER", 988 .queuecommand = iscsi_queuecommand, 989 .change_queue_depth = scsi_change_queue_depth, 990 .sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE, 991 .cmd_per_lun = ISER_DEF_CMD_PER_LUN, 992 .eh_timed_out = iscsi_eh_cmd_timed_out, 993 .eh_abort_handler = iscsi_eh_abort, 994 .eh_device_reset_handler= iscsi_eh_device_reset, 995 .eh_target_reset_handler = iscsi_eh_recover_target, 996 .target_alloc = iscsi_target_alloc, 997 .slave_alloc = iscsi_iser_slave_alloc, 998 .proc_name = "iscsi_iser", 999 .this_id = -1, 1000 .track_queue_depth = 1, 1001 }; 1002 1003 static struct iscsi_transport iscsi_iser_transport = { 1004 .owner = THIS_MODULE, 1005 .name = "iser", 1006 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO, 1007 /* session management */ 1008 .create_session = iscsi_iser_session_create, 1009 .destroy_session = iscsi_iser_session_destroy, 1010 /* connection management */ 1011 .create_conn = iscsi_iser_conn_create, 1012 .bind_conn = iscsi_iser_conn_bind, 1013 .destroy_conn = iscsi_conn_teardown, 1014 .attr_is_visible = iser_attr_is_visible, 1015 .set_param = iscsi_iser_set_param, 1016 .get_conn_param = iscsi_conn_get_param, 1017 .get_ep_param = iscsi_iser_get_ep_param, 1018 .get_session_param = iscsi_session_get_param, 1019 .start_conn = iscsi_iser_conn_start, 1020 .stop_conn = iscsi_iser_conn_stop, 1021 /* iscsi host params */ 1022 .get_host_param = iscsi_host_get_param, 1023 .set_host_param = iscsi_host_set_param, 1024 /* IO */ 1025 .send_pdu = iscsi_conn_send_pdu, 1026 .get_stats = iscsi_iser_conn_get_stats, 1027 .init_task = iscsi_iser_task_init, 1028 .xmit_task = iscsi_iser_task_xmit, 1029 .cleanup_task = iscsi_iser_cleanup_task, 1030 .alloc_pdu = iscsi_iser_pdu_alloc, 1031 .check_protection = iscsi_iser_check_protection, 1032 /* recovery */ 1033 .session_recovery_timedout = iscsi_session_recovery_timedout, 1034 1035 .ep_connect = iscsi_iser_ep_connect, 1036 .ep_poll = iscsi_iser_ep_poll, 1037 .ep_disconnect = iscsi_iser_ep_disconnect 1038 }; 1039 1040 static int __init iser_init(void) 1041 { 1042 int err; 1043 1044 iser_dbg("Starting iSER datamover...\n"); 1045 1046 if (iscsi_max_lun < 1) { 1047 iser_err("Invalid max_lun value of %u\n", iscsi_max_lun); 1048 return -EINVAL; 1049 } 1050 1051 memset(&ig, 0, sizeof(struct iser_global)); 1052 1053 ig.desc_cache = kmem_cache_create("iser_descriptors", 1054 sizeof(struct iser_tx_desc), 1055 0, SLAB_HWCACHE_ALIGN, 1056 NULL); 1057 if (ig.desc_cache == NULL) 1058 return -ENOMEM; 1059 1060 /* device init is called only after the first addr resolution */ 1061 mutex_init(&ig.device_list_mutex); 1062 INIT_LIST_HEAD(&ig.device_list); 1063 mutex_init(&ig.connlist_mutex); 1064 INIT_LIST_HEAD(&ig.connlist); 1065 1066 release_wq = alloc_workqueue("release workqueue", 0, 0); 1067 if (!release_wq) { 1068 iser_err("failed to allocate release workqueue\n"); 1069 err = -ENOMEM; 1070 goto err_alloc_wq; 1071 } 1072 1073 iscsi_iser_scsi_transport = iscsi_register_transport( 1074 &iscsi_iser_transport); 1075 if (!iscsi_iser_scsi_transport) { 1076 iser_err("iscsi_register_transport failed\n"); 1077 err = -EINVAL; 1078 goto err_reg; 1079 } 1080 1081 return 0; 1082 1083 err_reg: 1084 destroy_workqueue(release_wq); 1085 err_alloc_wq: 1086 kmem_cache_destroy(ig.desc_cache); 1087 1088 return err; 1089 } 1090 1091 static void __exit iser_exit(void) 1092 { 1093 struct iser_conn *iser_conn, *n; 1094 int connlist_empty; 1095 1096 iser_dbg("Removing iSER datamover...\n"); 1097 destroy_workqueue(release_wq); 1098 1099 mutex_lock(&ig.connlist_mutex); 1100 connlist_empty = list_empty(&ig.connlist); 1101 mutex_unlock(&ig.connlist_mutex); 1102 1103 if (!connlist_empty) { 1104 iser_err("Error cleanup stage completed but we still have iser " 1105 "connections, destroying them anyway\n"); 1106 list_for_each_entry_safe(iser_conn, n, &ig.connlist, 1107 conn_list) { 1108 iser_conn_release(iser_conn); 1109 } 1110 } 1111 1112 iscsi_unregister_transport(&iscsi_iser_transport); 1113 kmem_cache_destroy(ig.desc_cache); 1114 } 1115 1116 module_init(iser_init); 1117 module_exit(iser_exit); 1118