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 iscsi_session *session; 614 struct Scsi_Host *shost; 615 struct iser_conn *iser_conn = NULL; 616 struct ib_conn *ib_conn; 617 u32 max_fr_sectors; 618 u16 max_cmds; 619 620 shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0); 621 if (!shost) 622 return NULL; 623 shost->transportt = iscsi_iser_scsi_transport; 624 shost->cmd_per_lun = qdepth; 625 shost->max_lun = iscsi_max_lun; 626 shost->max_id = 0; 627 shost->max_channel = 0; 628 shost->max_cmd_len = 16; 629 630 /* 631 * older userspace tools (before 2.0-870) did not pass us 632 * the leading conn's ep so this will be NULL; 633 */ 634 if (ep) { 635 iser_conn = ep->dd_data; 636 max_cmds = iser_conn->max_cmds; 637 shost->sg_tablesize = iser_conn->scsi_sg_tablesize; 638 639 mutex_lock(&iser_conn->state_mutex); 640 if (iser_conn->state != ISER_CONN_UP) { 641 iser_err("iser conn %p already started teardown\n", 642 iser_conn); 643 mutex_unlock(&iser_conn->state_mutex); 644 goto free_host; 645 } 646 647 ib_conn = &iser_conn->ib_conn; 648 if (ib_conn->pi_support) { 649 u32 sig_caps = ib_conn->device->ib_device->attrs.sig_prot_cap; 650 651 scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps)); 652 scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP | 653 SHOST_DIX_GUARD_CRC); 654 } 655 656 if (iscsi_host_add(shost, 657 ib_conn->device->ib_device->dev.parent)) { 658 mutex_unlock(&iser_conn->state_mutex); 659 goto free_host; 660 } 661 mutex_unlock(&iser_conn->state_mutex); 662 } else { 663 max_cmds = ISER_DEF_XMIT_CMDS_MAX; 664 if (iscsi_host_add(shost, NULL)) 665 goto free_host; 666 } 667 668 /* 669 * FRs or FMRs can only map up to a (device) page per entry, but if the 670 * first entry is misaligned we'll end up using using two entries 671 * (head and tail) for a single page worth data, so we have to drop 672 * one segment from the calculation. 673 */ 674 max_fr_sectors = ((shost->sg_tablesize - 1) * PAGE_SIZE) >> 9; 675 shost->max_sectors = min(iser_max_sectors, max_fr_sectors); 676 677 iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n", 678 iser_conn, shost->sg_tablesize, 679 shost->max_sectors); 680 681 if (cmds_max > max_cmds) { 682 iser_info("cmds_max changed from %u to %u\n", 683 cmds_max, max_cmds); 684 cmds_max = max_cmds; 685 } 686 687 cls_session = iscsi_session_setup(&iscsi_iser_transport, shost, 688 cmds_max, 0, 689 sizeof(struct iscsi_iser_task), 690 initial_cmdsn, 0); 691 if (!cls_session) 692 goto remove_host; 693 session = cls_session->dd_data; 694 695 shost->can_queue = session->scsi_cmds_max; 696 return cls_session; 697 698 remove_host: 699 iscsi_host_remove(shost); 700 free_host: 701 iscsi_host_free(shost); 702 return NULL; 703 } 704 705 static int 706 iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn, 707 enum iscsi_param param, char *buf, int buflen) 708 { 709 int value; 710 711 switch (param) { 712 case ISCSI_PARAM_MAX_RECV_DLENGTH: 713 /* TBD */ 714 break; 715 case ISCSI_PARAM_HDRDGST_EN: 716 sscanf(buf, "%d", &value); 717 if (value) { 718 iser_err("DataDigest wasn't negotiated to None\n"); 719 return -EPROTO; 720 } 721 break; 722 case ISCSI_PARAM_DATADGST_EN: 723 sscanf(buf, "%d", &value); 724 if (value) { 725 iser_err("DataDigest wasn't negotiated to None\n"); 726 return -EPROTO; 727 } 728 break; 729 case ISCSI_PARAM_IFMARKER_EN: 730 sscanf(buf, "%d", &value); 731 if (value) { 732 iser_err("IFMarker wasn't negotiated to No\n"); 733 return -EPROTO; 734 } 735 break; 736 case ISCSI_PARAM_OFMARKER_EN: 737 sscanf(buf, "%d", &value); 738 if (value) { 739 iser_err("OFMarker wasn't negotiated to No\n"); 740 return -EPROTO; 741 } 742 break; 743 default: 744 return iscsi_set_param(cls_conn, param, buf, buflen); 745 } 746 747 return 0; 748 } 749 750 /** 751 * iscsi_iser_set_param() - set class connection parameter 752 * @cls_conn: iscsi class connection 753 * @stats: iscsi stats to output 754 * 755 * Output connection statistics. 756 */ 757 static void 758 iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats) 759 { 760 struct iscsi_conn *conn = cls_conn->dd_data; 761 762 stats->txdata_octets = conn->txdata_octets; 763 stats->rxdata_octets = conn->rxdata_octets; 764 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt; 765 stats->dataout_pdus = conn->dataout_pdus_cnt; 766 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt; 767 stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */ 768 stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */ 769 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt; 770 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt; 771 stats->custom_length = 0; 772 } 773 774 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep, 775 enum iscsi_param param, char *buf) 776 { 777 struct iser_conn *iser_conn = ep->dd_data; 778 int len; 779 780 switch (param) { 781 case ISCSI_PARAM_CONN_PORT: 782 case ISCSI_PARAM_CONN_ADDRESS: 783 if (!iser_conn || !iser_conn->ib_conn.cma_id) 784 return -ENOTCONN; 785 786 return iscsi_conn_get_addr_param((struct sockaddr_storage *) 787 &iser_conn->ib_conn.cma_id->route.addr.dst_addr, 788 param, buf); 789 break; 790 default: 791 return -ENOSYS; 792 } 793 794 return len; 795 } 796 797 /** 798 * iscsi_iser_ep_connect() - Initiate iSER connection establishment 799 * @shost: scsi_host 800 * @dst_addr: destination address 801 * @non-blocking: indicate if routine can block 802 * 803 * Allocate an iscsi endpoint, an iser_conn structure and bind them. 804 * After that start RDMA connection establishment via rdma_cm. We 805 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown 806 * the endpoint will be destroyed at ep_disconnect while iser_conn will 807 * cleanup its resources asynchronuously. 808 * 809 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error) 810 * if fails. 811 */ 812 static struct iscsi_endpoint * 813 iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr, 814 int non_blocking) 815 { 816 int err; 817 struct iser_conn *iser_conn; 818 struct iscsi_endpoint *ep; 819 820 ep = iscsi_create_endpoint(0); 821 if (!ep) 822 return ERR_PTR(-ENOMEM); 823 824 iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL); 825 if (!iser_conn) { 826 err = -ENOMEM; 827 goto failure; 828 } 829 830 ep->dd_data = iser_conn; 831 iser_conn->ep = ep; 832 iser_conn_init(iser_conn); 833 834 err = iser_connect(iser_conn, NULL, dst_addr, non_blocking); 835 if (err) 836 goto failure; 837 838 return ep; 839 failure: 840 iscsi_destroy_endpoint(ep); 841 return ERR_PTR(err); 842 } 843 844 /** 845 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete 846 * @ep: iscsi endpoint (created at ep_connect) 847 * @timeout_ms: polling timeout allowed in ms. 848 * 849 * This routine boils down to waiting for up_completion signaling 850 * that cma_id got CONNECTED event. 851 * 852 * Return: 1 if succeeded in connection establishment, 0 if timeout expired 853 * (libiscsi will retry will kick in) or -1 if interrupted by signal 854 * or more likely iser connection state transitioned to TEMINATING or 855 * DOWN during the wait period. 856 */ 857 static int 858 iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms) 859 { 860 struct iser_conn *iser_conn = ep->dd_data; 861 int rc; 862 863 rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion, 864 msecs_to_jiffies(timeout_ms)); 865 /* if conn establishment failed, return error code to iscsi */ 866 if (rc == 0) { 867 mutex_lock(&iser_conn->state_mutex); 868 if (iser_conn->state == ISER_CONN_TERMINATING || 869 iser_conn->state == ISER_CONN_DOWN) 870 rc = -1; 871 mutex_unlock(&iser_conn->state_mutex); 872 } 873 874 iser_info("iser conn %p rc = %d\n", iser_conn, rc); 875 876 if (rc > 0) 877 return 1; /* success, this is the equivalent of POLLOUT */ 878 else if (!rc) 879 return 0; /* timeout */ 880 else 881 return rc; /* signal */ 882 } 883 884 /** 885 * iscsi_iser_ep_disconnect() - Initiate connection teardown process 886 * @ep: iscsi endpoint handle 887 * 888 * This routine is not blocked by iser and RDMA termination process 889 * completion as we queue a deffered work for iser/RDMA destruction 890 * and cleanup or actually call it immediately in case we didn't pass 891 * iscsi conn bind/start stage, thus it is safe. 892 */ 893 static void 894 iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep) 895 { 896 struct iser_conn *iser_conn = ep->dd_data; 897 898 iser_info("ep %p iser conn %p\n", ep, iser_conn); 899 900 mutex_lock(&iser_conn->state_mutex); 901 iser_conn_terminate(iser_conn); 902 903 /* 904 * if iser_conn and iscsi_conn are bound, we must wait for 905 * iscsi_conn_stop and flush errors completion before freeing 906 * the iser resources. Otherwise we are safe to free resources 907 * immediately. 908 */ 909 if (iser_conn->iscsi_conn) { 910 INIT_WORK(&iser_conn->release_work, iser_release_work); 911 queue_work(release_wq, &iser_conn->release_work); 912 mutex_unlock(&iser_conn->state_mutex); 913 } else { 914 iser_conn->state = ISER_CONN_DOWN; 915 mutex_unlock(&iser_conn->state_mutex); 916 iser_conn_release(iser_conn); 917 } 918 919 iscsi_destroy_endpoint(ep); 920 } 921 922 static umode_t iser_attr_is_visible(int param_type, int param) 923 { 924 switch (param_type) { 925 case ISCSI_HOST_PARAM: 926 switch (param) { 927 case ISCSI_HOST_PARAM_NETDEV_NAME: 928 case ISCSI_HOST_PARAM_HWADDRESS: 929 case ISCSI_HOST_PARAM_INITIATOR_NAME: 930 return S_IRUGO; 931 default: 932 return 0; 933 } 934 case ISCSI_PARAM: 935 switch (param) { 936 case ISCSI_PARAM_MAX_RECV_DLENGTH: 937 case ISCSI_PARAM_MAX_XMIT_DLENGTH: 938 case ISCSI_PARAM_HDRDGST_EN: 939 case ISCSI_PARAM_DATADGST_EN: 940 case ISCSI_PARAM_CONN_ADDRESS: 941 case ISCSI_PARAM_CONN_PORT: 942 case ISCSI_PARAM_EXP_STATSN: 943 case ISCSI_PARAM_PERSISTENT_ADDRESS: 944 case ISCSI_PARAM_PERSISTENT_PORT: 945 case ISCSI_PARAM_PING_TMO: 946 case ISCSI_PARAM_RECV_TMO: 947 case ISCSI_PARAM_INITIAL_R2T_EN: 948 case ISCSI_PARAM_MAX_R2T: 949 case ISCSI_PARAM_IMM_DATA_EN: 950 case ISCSI_PARAM_FIRST_BURST: 951 case ISCSI_PARAM_MAX_BURST: 952 case ISCSI_PARAM_PDU_INORDER_EN: 953 case ISCSI_PARAM_DATASEQ_INORDER_EN: 954 case ISCSI_PARAM_TARGET_NAME: 955 case ISCSI_PARAM_TPGT: 956 case ISCSI_PARAM_USERNAME: 957 case ISCSI_PARAM_PASSWORD: 958 case ISCSI_PARAM_USERNAME_IN: 959 case ISCSI_PARAM_PASSWORD_IN: 960 case ISCSI_PARAM_FAST_ABORT: 961 case ISCSI_PARAM_ABORT_TMO: 962 case ISCSI_PARAM_LU_RESET_TMO: 963 case ISCSI_PARAM_TGT_RESET_TMO: 964 case ISCSI_PARAM_IFACE_NAME: 965 case ISCSI_PARAM_INITIATOR_NAME: 966 case ISCSI_PARAM_DISCOVERY_SESS: 967 return S_IRUGO; 968 default: 969 return 0; 970 } 971 } 972 973 return 0; 974 } 975 976 static int iscsi_iser_slave_alloc(struct scsi_device *sdev) 977 { 978 struct iscsi_session *session; 979 struct iser_conn *iser_conn; 980 struct ib_device *ib_dev; 981 982 mutex_lock(&unbind_iser_conn_mutex); 983 984 session = starget_to_session(scsi_target(sdev))->dd_data; 985 iser_conn = session->leadconn->dd_data; 986 if (!iser_conn) { 987 mutex_unlock(&unbind_iser_conn_mutex); 988 return -ENOTCONN; 989 } 990 ib_dev = iser_conn->ib_conn.device->ib_device; 991 992 if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)) 993 blk_queue_virt_boundary(sdev->request_queue, ~MASK_4K); 994 995 mutex_unlock(&unbind_iser_conn_mutex); 996 997 return 0; 998 } 999 1000 static struct scsi_host_template iscsi_iser_sht = { 1001 .module = THIS_MODULE, 1002 .name = "iSCSI Initiator over iSER", 1003 .queuecommand = iscsi_queuecommand, 1004 .change_queue_depth = scsi_change_queue_depth, 1005 .sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE, 1006 .cmd_per_lun = ISER_DEF_CMD_PER_LUN, 1007 .eh_timed_out = iscsi_eh_cmd_timed_out, 1008 .eh_abort_handler = iscsi_eh_abort, 1009 .eh_device_reset_handler= iscsi_eh_device_reset, 1010 .eh_target_reset_handler = iscsi_eh_recover_target, 1011 .target_alloc = iscsi_target_alloc, 1012 .use_clustering = ENABLE_CLUSTERING, 1013 .slave_alloc = iscsi_iser_slave_alloc, 1014 .proc_name = "iscsi_iser", 1015 .this_id = -1, 1016 .track_queue_depth = 1, 1017 }; 1018 1019 static struct iscsi_transport iscsi_iser_transport = { 1020 .owner = THIS_MODULE, 1021 .name = "iser", 1022 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO, 1023 /* session management */ 1024 .create_session = iscsi_iser_session_create, 1025 .destroy_session = iscsi_iser_session_destroy, 1026 /* connection management */ 1027 .create_conn = iscsi_iser_conn_create, 1028 .bind_conn = iscsi_iser_conn_bind, 1029 .destroy_conn = iscsi_conn_teardown, 1030 .attr_is_visible = iser_attr_is_visible, 1031 .set_param = iscsi_iser_set_param, 1032 .get_conn_param = iscsi_conn_get_param, 1033 .get_ep_param = iscsi_iser_get_ep_param, 1034 .get_session_param = iscsi_session_get_param, 1035 .start_conn = iscsi_iser_conn_start, 1036 .stop_conn = iscsi_iser_conn_stop, 1037 /* iscsi host params */ 1038 .get_host_param = iscsi_host_get_param, 1039 .set_host_param = iscsi_host_set_param, 1040 /* IO */ 1041 .send_pdu = iscsi_conn_send_pdu, 1042 .get_stats = iscsi_iser_conn_get_stats, 1043 .init_task = iscsi_iser_task_init, 1044 .xmit_task = iscsi_iser_task_xmit, 1045 .cleanup_task = iscsi_iser_cleanup_task, 1046 .alloc_pdu = iscsi_iser_pdu_alloc, 1047 .check_protection = iscsi_iser_check_protection, 1048 /* recovery */ 1049 .session_recovery_timedout = iscsi_session_recovery_timedout, 1050 1051 .ep_connect = iscsi_iser_ep_connect, 1052 .ep_poll = iscsi_iser_ep_poll, 1053 .ep_disconnect = iscsi_iser_ep_disconnect 1054 }; 1055 1056 static int __init iser_init(void) 1057 { 1058 int err; 1059 1060 iser_dbg("Starting iSER datamover...\n"); 1061 1062 if (iscsi_max_lun < 1) { 1063 iser_err("Invalid max_lun value of %u\n", iscsi_max_lun); 1064 return -EINVAL; 1065 } 1066 1067 memset(&ig, 0, sizeof(struct iser_global)); 1068 1069 ig.desc_cache = kmem_cache_create("iser_descriptors", 1070 sizeof(struct iser_tx_desc), 1071 0, SLAB_HWCACHE_ALIGN, 1072 NULL); 1073 if (ig.desc_cache == NULL) 1074 return -ENOMEM; 1075 1076 /* device init is called only after the first addr resolution */ 1077 mutex_init(&ig.device_list_mutex); 1078 INIT_LIST_HEAD(&ig.device_list); 1079 mutex_init(&ig.connlist_mutex); 1080 INIT_LIST_HEAD(&ig.connlist); 1081 1082 release_wq = alloc_workqueue("release workqueue", 0, 0); 1083 if (!release_wq) { 1084 iser_err("failed to allocate release workqueue\n"); 1085 err = -ENOMEM; 1086 goto err_alloc_wq; 1087 } 1088 1089 iscsi_iser_scsi_transport = iscsi_register_transport( 1090 &iscsi_iser_transport); 1091 if (!iscsi_iser_scsi_transport) { 1092 iser_err("iscsi_register_transport failed\n"); 1093 err = -EINVAL; 1094 goto err_reg; 1095 } 1096 1097 return 0; 1098 1099 err_reg: 1100 destroy_workqueue(release_wq); 1101 err_alloc_wq: 1102 kmem_cache_destroy(ig.desc_cache); 1103 1104 return err; 1105 } 1106 1107 static void __exit iser_exit(void) 1108 { 1109 struct iser_conn *iser_conn, *n; 1110 int connlist_empty; 1111 1112 iser_dbg("Removing iSER datamover...\n"); 1113 destroy_workqueue(release_wq); 1114 1115 mutex_lock(&ig.connlist_mutex); 1116 connlist_empty = list_empty(&ig.connlist); 1117 mutex_unlock(&ig.connlist_mutex); 1118 1119 if (!connlist_empty) { 1120 iser_err("Error cleanup stage completed but we still have iser " 1121 "connections, destroying them anyway\n"); 1122 list_for_each_entry_safe(iser_conn, n, &ig.connlist, 1123 conn_list) { 1124 iser_conn_release(iser_conn); 1125 } 1126 } 1127 1128 iscsi_unregister_transport(&iscsi_iser_transport); 1129 kmem_cache_destroy(ig.desc_cache); 1130 } 1131 1132 module_init(iser_init); 1133 module_exit(iser_exit); 1134