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 int iscsi_iser_set(const char *val, const struct kernel_param *kp); 93 static const struct kernel_param_ops iscsi_iser_size_ops = { 94 .set = iscsi_iser_set, 95 .get = param_get_uint, 96 }; 97 98 static unsigned int iscsi_max_lun = 512; 99 module_param_cb(max_lun, &iscsi_iser_size_ops, &iscsi_max_lun, S_IRUGO); 100 MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session, should > 0 (default:512)"); 101 102 unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS; 103 module_param_cb(max_sectors, &iscsi_iser_size_ops, &iser_max_sectors, 104 S_IRUGO | S_IWUSR); 105 MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command, should > 0 (default:1024)"); 106 107 bool iser_always_reg = true; 108 module_param_named(always_register, iser_always_reg, bool, S_IRUGO); 109 MODULE_PARM_DESC(always_register, 110 "Always register memory, even for continuous memory regions (default:true)"); 111 112 bool iser_pi_enable = false; 113 module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO); 114 MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)"); 115 116 int iser_pi_guard; 117 module_param_named(pi_guard, iser_pi_guard, int, S_IRUGO); 118 MODULE_PARM_DESC(pi_guard, "T10-PI guard_type [deprecated]"); 119 120 static int iscsi_iser_set(const char *val, const struct kernel_param *kp) 121 { 122 int ret; 123 unsigned int n = 0; 124 125 ret = kstrtouint(val, 10, &n); 126 if (ret != 0 || n == 0) 127 return -EINVAL; 128 129 return param_set_uint(val, kp); 130 } 131 132 /* 133 * iscsi_iser_recv() - Process a successful recv completion 134 * @conn: iscsi connection 135 * @hdr: iscsi header 136 * @rx_data: buffer containing receive data payload 137 * @rx_data_len: length of rx_data 138 * 139 * Notes: In case of data length errors or iscsi PDU completion failures 140 * this routine will signal iscsi layer of connection failure. 141 */ 142 void 143 iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr, 144 char *rx_data, int rx_data_len) 145 { 146 int rc = 0; 147 int datalen; 148 149 /* verify PDU length */ 150 datalen = ntoh24(hdr->dlength); 151 if (datalen > rx_data_len || (datalen + 4) < rx_data_len) { 152 iser_err("wrong datalen %d (hdr), %d (IB)\n", 153 datalen, rx_data_len); 154 rc = ISCSI_ERR_DATALEN; 155 goto error; 156 } 157 158 if (datalen != rx_data_len) 159 iser_dbg("aligned datalen (%d) hdr, %d (IB)\n", 160 datalen, rx_data_len); 161 162 rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len); 163 if (rc && rc != ISCSI_ERR_NO_SCSI_CMD) 164 goto error; 165 166 return; 167 error: 168 iscsi_conn_failure(conn, rc); 169 } 170 171 /** 172 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU 173 * @task: iscsi task 174 * @opcode: iscsi command opcode 175 * 176 * Netes: This routine can't fail, just assign iscsi task 177 * hdr and max hdr size. 178 */ 179 static int 180 iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 181 { 182 struct iscsi_iser_task *iser_task = task->dd_data; 183 184 task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header; 185 task->hdr_max = sizeof(iser_task->desc.iscsi_header); 186 187 return 0; 188 } 189 190 /** 191 * iser_initialize_task_headers() - Initialize task headers 192 * @task: iscsi task 193 * @tx_desc: iser tx descriptor 194 * 195 * Notes: 196 * This routine may race with iser teardown flow for scsi 197 * error handling TMFs. So for TMF we should acquire the 198 * state mutex to avoid dereferencing the IB device which 199 * may have already been terminated. 200 */ 201 int 202 iser_initialize_task_headers(struct iscsi_task *task, 203 struct iser_tx_desc *tx_desc) 204 { 205 struct iser_conn *iser_conn = task->conn->dd_data; 206 struct iser_device *device = iser_conn->ib_conn.device; 207 struct iscsi_iser_task *iser_task = task->dd_data; 208 u64 dma_addr; 209 210 if (unlikely(iser_conn->state != ISER_CONN_UP)) 211 return -ENODEV; 212 213 dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc, 214 ISER_HEADERS_LEN, DMA_TO_DEVICE); 215 if (ib_dma_mapping_error(device->ib_device, dma_addr)) 216 return -ENOMEM; 217 218 tx_desc->inv_wr.next = NULL; 219 tx_desc->reg_wr.wr.next = NULL; 220 tx_desc->mapped = true; 221 tx_desc->dma_addr = dma_addr; 222 tx_desc->tx_sg[0].addr = tx_desc->dma_addr; 223 tx_desc->tx_sg[0].length = ISER_HEADERS_LEN; 224 tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey; 225 226 iser_task->iser_conn = iser_conn; 227 228 return 0; 229 } 230 231 /** 232 * iscsi_iser_task_init() - Initialize iscsi-iser task 233 * @task: iscsi task 234 * 235 * Initialize the task for the scsi command or mgmt command. 236 * 237 * Return: Returns zero on success or -ENOMEM when failing 238 * to init task headers (dma mapping error). 239 */ 240 static int 241 iscsi_iser_task_init(struct iscsi_task *task) 242 { 243 struct iscsi_iser_task *iser_task = task->dd_data; 244 int ret; 245 246 ret = iser_initialize_task_headers(task, &iser_task->desc); 247 if (ret) { 248 iser_err("Failed to init task %p, err = %d\n", 249 iser_task, ret); 250 return ret; 251 } 252 253 /* mgmt task */ 254 if (!task->sc) 255 return 0; 256 257 iser_task->command_sent = 0; 258 iser_task_rdma_init(iser_task); 259 iser_task->sc = task->sc; 260 261 return 0; 262 } 263 264 /** 265 * iscsi_iser_mtask_xmit() - xmit management (immediate) task 266 * @conn: iscsi connection 267 * @task: task management task 268 * 269 * Notes: 270 * The function can return -EAGAIN in which case caller must 271 * call it again later, or recover. '0' return code means successful 272 * xmit. 273 * 274 **/ 275 static int 276 iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task) 277 { 278 int error = 0; 279 280 iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt); 281 282 error = iser_send_control(conn, task); 283 284 /* since iser xmits control with zero copy, tasks can not be recycled 285 * right after sending them. 286 * The recycling scheme is based on whether a response is expected 287 * - if yes, the task is recycled at iscsi_complete_pdu 288 * - if no, the task is recycled at iser_snd_completion 289 */ 290 return error; 291 } 292 293 static int 294 iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn, 295 struct iscsi_task *task) 296 { 297 struct iscsi_r2t_info *r2t = &task->unsol_r2t; 298 struct iscsi_data hdr; 299 int error = 0; 300 301 /* Send data-out PDUs while there's still unsolicited data to send */ 302 while (iscsi_task_has_unsol_data(task)) { 303 iscsi_prep_data_out_pdu(task, r2t, &hdr); 304 iser_dbg("Sending data-out: itt 0x%x, data count %d\n", 305 hdr.itt, r2t->data_count); 306 307 /* the buffer description has been passed with the command */ 308 /* Send the command */ 309 error = iser_send_data_out(conn, task, &hdr); 310 if (error) { 311 r2t->datasn--; 312 goto iscsi_iser_task_xmit_unsol_data_exit; 313 } 314 r2t->sent += r2t->data_count; 315 iser_dbg("Need to send %d more as data-out PDUs\n", 316 r2t->data_length - r2t->sent); 317 } 318 319 iscsi_iser_task_xmit_unsol_data_exit: 320 return error; 321 } 322 323 /** 324 * iscsi_iser_task_xmit() - xmit iscsi-iser task 325 * @task: iscsi task 326 * 327 * Return: zero on success or escalates $error on failure. 328 */ 329 static int 330 iscsi_iser_task_xmit(struct iscsi_task *task) 331 { 332 struct iscsi_conn *conn = task->conn; 333 struct iscsi_iser_task *iser_task = task->dd_data; 334 int error = 0; 335 336 if (!task->sc) 337 return iscsi_iser_mtask_xmit(conn, task); 338 339 if (task->sc->sc_data_direction == DMA_TO_DEVICE) { 340 BUG_ON(scsi_bufflen(task->sc) == 0); 341 342 iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n", 343 task->itt, scsi_bufflen(task->sc), 344 task->imm_count, task->unsol_r2t.data_length); 345 } 346 347 iser_dbg("ctask xmit [cid %d itt 0x%x]\n", 348 conn->id, task->itt); 349 350 /* Send the cmd PDU */ 351 if (!iser_task->command_sent) { 352 error = iser_send_command(conn, task); 353 if (error) 354 goto iscsi_iser_task_xmit_exit; 355 iser_task->command_sent = 1; 356 } 357 358 /* Send unsolicited data-out PDU(s) if necessary */ 359 if (iscsi_task_has_unsol_data(task)) 360 error = iscsi_iser_task_xmit_unsol_data(conn, task); 361 362 iscsi_iser_task_xmit_exit: 363 return error; 364 } 365 366 /** 367 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task 368 * @task: iscsi task 369 * 370 * Notes: In case the RDMA device is already NULL (might have 371 * been removed in DEVICE_REMOVAL CM event it will bail-out 372 * without doing dma unmapping. 373 */ 374 static void iscsi_iser_cleanup_task(struct iscsi_task *task) 375 { 376 struct iscsi_iser_task *iser_task = task->dd_data; 377 struct iser_tx_desc *tx_desc = &iser_task->desc; 378 struct iser_conn *iser_conn = task->conn->dd_data; 379 struct iser_device *device = iser_conn->ib_conn.device; 380 381 /* DEVICE_REMOVAL event might have already released the device */ 382 if (!device) 383 return; 384 385 if (likely(tx_desc->mapped)) { 386 ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr, 387 ISER_HEADERS_LEN, DMA_TO_DEVICE); 388 tx_desc->mapped = false; 389 } 390 391 /* mgmt tasks do not need special cleanup */ 392 if (!task->sc) 393 return; 394 395 if (iser_task->status == ISER_TASK_STATUS_STARTED) { 396 iser_task->status = ISER_TASK_STATUS_COMPLETED; 397 iser_task_rdma_finalize(iser_task); 398 } 399 } 400 401 /** 402 * iscsi_iser_check_protection() - check protection information status of task. 403 * @task: iscsi task 404 * @sector: error sector if exsists (output) 405 * 406 * Return: zero if no data-integrity errors have occured 407 * 0x1: data-integrity error occured in the guard-block 408 * 0x2: data-integrity error occured in the reference tag 409 * 0x3: data-integrity error occured in the application tag 410 * 411 * In addition the error sector is marked. 412 */ 413 static u8 414 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector) 415 { 416 struct iscsi_iser_task *iser_task = task->dd_data; 417 enum iser_data_dir dir = iser_task->dir[ISER_DIR_IN] ? 418 ISER_DIR_IN : ISER_DIR_OUT; 419 420 return iser_check_task_pi_status(iser_task, dir, sector); 421 } 422 423 /** 424 * iscsi_iser_conn_create() - create a new iscsi-iser connection 425 * @cls_session: iscsi class connection 426 * @conn_idx: connection index within the session (for MCS) 427 * 428 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL 429 * otherwise. 430 */ 431 static struct iscsi_cls_conn * 432 iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, 433 uint32_t conn_idx) 434 { 435 struct iscsi_conn *conn; 436 struct iscsi_cls_conn *cls_conn; 437 438 cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx); 439 if (!cls_conn) 440 return NULL; 441 conn = cls_conn->dd_data; 442 443 /* 444 * due to issues with the login code re iser sematics 445 * this not set in iscsi_conn_setup - FIXME 446 */ 447 conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN; 448 449 return cls_conn; 450 } 451 452 /** 453 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures 454 * @cls_session: iscsi class session 455 * @cls_conn: iscsi class connection 456 * @transport_eph: transport end-point handle 457 * @is_leading: indicate if this is the session leading connection (MCS) 458 * 459 * Return: zero on success, $error if iscsi_conn_bind fails and 460 * -EINVAL in case end-point doesn't exsits anymore or iser connection 461 * state is not UP (teardown already started). 462 */ 463 static int 464 iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session, 465 struct iscsi_cls_conn *cls_conn, 466 uint64_t transport_eph, 467 int is_leading) 468 { 469 struct iscsi_conn *conn = cls_conn->dd_data; 470 struct iser_conn *iser_conn; 471 struct iscsi_endpoint *ep; 472 int error; 473 474 error = iscsi_conn_bind(cls_session, cls_conn, is_leading); 475 if (error) 476 return error; 477 478 /* the transport ep handle comes from user space so it must be 479 * verified against the global ib connections list */ 480 ep = iscsi_lookup_endpoint(transport_eph); 481 if (!ep) { 482 iser_err("can't bind eph %llx\n", 483 (unsigned long long)transport_eph); 484 return -EINVAL; 485 } 486 iser_conn = ep->dd_data; 487 488 mutex_lock(&iser_conn->state_mutex); 489 if (iser_conn->state != ISER_CONN_UP) { 490 error = -EINVAL; 491 iser_err("iser_conn %p state is %d, teardown started\n", 492 iser_conn, iser_conn->state); 493 goto out; 494 } 495 496 error = iser_alloc_rx_descriptors(iser_conn, conn->session); 497 if (error) 498 goto out; 499 500 /* binds the iSER connection retrieved from the previously 501 * connected ep_handle to the iSCSI layer connection. exchanges 502 * connection pointers */ 503 iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn); 504 505 conn->dd_data = iser_conn; 506 iser_conn->iscsi_conn = conn; 507 508 out: 509 iscsi_put_endpoint(ep); 510 mutex_unlock(&iser_conn->state_mutex); 511 return error; 512 } 513 514 /** 515 * iscsi_iser_conn_start() - start iscsi-iser connection 516 * @cls_conn: iscsi class connection 517 * 518 * Notes: Here iser intialize (or re-initialize) stop_completion as 519 * from this point iscsi must call conn_stop in session/connection 520 * teardown so iser transport must wait for it. 521 */ 522 static int 523 iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn) 524 { 525 struct iscsi_conn *iscsi_conn; 526 struct iser_conn *iser_conn; 527 528 iscsi_conn = cls_conn->dd_data; 529 iser_conn = iscsi_conn->dd_data; 530 reinit_completion(&iser_conn->stop_completion); 531 532 return iscsi_conn_start(cls_conn); 533 } 534 535 /** 536 * iscsi_iser_conn_stop() - stop iscsi-iser connection 537 * @cls_conn: iscsi class connection 538 * @flag: indicate if recover or terminate (passed as is) 539 * 540 * Notes: Calling iscsi_conn_stop might theoretically race with 541 * DEVICE_REMOVAL event and dereference a previously freed RDMA device 542 * handle, so we call it under iser the state lock to protect against 543 * this kind of race. 544 */ 545 static void 546 iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 547 { 548 struct iscsi_conn *conn = cls_conn->dd_data; 549 struct iser_conn *iser_conn = conn->dd_data; 550 551 iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn); 552 553 /* 554 * Userspace may have goofed up and not bound the connection or 555 * might have only partially setup the connection. 556 */ 557 if (iser_conn) { 558 mutex_lock(&iser_conn->state_mutex); 559 mutex_lock(&unbind_iser_conn_mutex); 560 iser_conn_terminate(iser_conn); 561 iscsi_conn_stop(cls_conn, flag); 562 563 /* unbind */ 564 iser_conn->iscsi_conn = NULL; 565 conn->dd_data = NULL; 566 mutex_unlock(&unbind_iser_conn_mutex); 567 568 complete(&iser_conn->stop_completion); 569 mutex_unlock(&iser_conn->state_mutex); 570 } else { 571 iscsi_conn_stop(cls_conn, flag); 572 } 573 } 574 575 /** 576 * iscsi_iser_session_destroy() - destroy iscsi-iser session 577 * @cls_session: iscsi class session 578 * 579 * Removes and free iscsi host. 580 */ 581 static void 582 iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session) 583 { 584 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 585 586 iscsi_session_teardown(cls_session); 587 iscsi_host_remove(shost); 588 iscsi_host_free(shost); 589 } 590 591 static inline unsigned int 592 iser_dif_prot_caps(int prot_caps) 593 { 594 int ret = 0; 595 596 if (prot_caps & IB_PROT_T10DIF_TYPE_1) 597 ret |= SHOST_DIF_TYPE1_PROTECTION | 598 SHOST_DIX_TYPE0_PROTECTION | 599 SHOST_DIX_TYPE1_PROTECTION; 600 if (prot_caps & IB_PROT_T10DIF_TYPE_2) 601 ret |= SHOST_DIF_TYPE2_PROTECTION | 602 SHOST_DIX_TYPE2_PROTECTION; 603 if (prot_caps & IB_PROT_T10DIF_TYPE_3) 604 ret |= SHOST_DIF_TYPE3_PROTECTION | 605 SHOST_DIX_TYPE3_PROTECTION; 606 607 return ret; 608 } 609 610 /** 611 * iscsi_iser_session_create() - create an iscsi-iser session 612 * @ep: iscsi end-point handle 613 * @cmds_max: maximum commands in this session 614 * @qdepth: session command queue depth 615 * @initial_cmdsn: initiator command sequnce number 616 * 617 * Allocates and adds a scsi host, expose DIF supprot if 618 * exists, and sets up an iscsi session. 619 */ 620 static struct iscsi_cls_session * 621 iscsi_iser_session_create(struct iscsi_endpoint *ep, 622 uint16_t cmds_max, uint16_t qdepth, 623 uint32_t initial_cmdsn) 624 { 625 struct iscsi_cls_session *cls_session; 626 struct Scsi_Host *shost; 627 struct iser_conn *iser_conn = NULL; 628 struct ib_conn *ib_conn; 629 struct ib_device *ib_dev; 630 u32 max_fr_sectors; 631 632 shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0); 633 if (!shost) 634 return NULL; 635 shost->transportt = iscsi_iser_scsi_transport; 636 shost->cmd_per_lun = qdepth; 637 shost->max_lun = iscsi_max_lun; 638 shost->max_id = 0; 639 shost->max_channel = 0; 640 shost->max_cmd_len = 16; 641 642 /* 643 * older userspace tools (before 2.0-870) did not pass us 644 * the leading conn's ep so this will be NULL; 645 */ 646 if (ep) { 647 iser_conn = ep->dd_data; 648 shost->sg_tablesize = iser_conn->scsi_sg_tablesize; 649 shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds); 650 651 mutex_lock(&iser_conn->state_mutex); 652 if (iser_conn->state != ISER_CONN_UP) { 653 iser_err("iser conn %p already started teardown\n", 654 iser_conn); 655 mutex_unlock(&iser_conn->state_mutex); 656 goto free_host; 657 } 658 659 ib_conn = &iser_conn->ib_conn; 660 ib_dev = ib_conn->device->ib_device; 661 if (ib_conn->pi_support) { 662 u32 sig_caps = ib_dev->attrs.sig_prot_cap; 663 664 shost->sg_prot_tablesize = shost->sg_tablesize; 665 scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps)); 666 scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP | 667 SHOST_DIX_GUARD_CRC); 668 } 669 670 if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)) 671 shost->virt_boundary_mask = SZ_4K - 1; 672 673 if (iscsi_host_add(shost, ib_dev->dev.parent)) { 674 mutex_unlock(&iser_conn->state_mutex); 675 goto free_host; 676 } 677 mutex_unlock(&iser_conn->state_mutex); 678 } else { 679 shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX); 680 if (iscsi_host_add(shost, NULL)) 681 goto free_host; 682 } 683 684 max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9; 685 shost->max_sectors = min(iser_max_sectors, max_fr_sectors); 686 687 iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n", 688 iser_conn, shost->sg_tablesize, 689 shost->max_sectors); 690 691 if (shost->max_sectors < iser_max_sectors) 692 iser_warn("max_sectors was reduced from %u to %u\n", 693 iser_max_sectors, shost->max_sectors); 694 695 cls_session = iscsi_session_setup(&iscsi_iser_transport, shost, 696 shost->can_queue, 0, 697 sizeof(struct iscsi_iser_task), 698 initial_cmdsn, 0); 699 if (!cls_session) 700 goto remove_host; 701 702 return cls_session; 703 704 remove_host: 705 iscsi_host_remove(shost); 706 free_host: 707 iscsi_host_free(shost); 708 return NULL; 709 } 710 711 static int 712 iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn, 713 enum iscsi_param param, char *buf, int buflen) 714 { 715 int value; 716 717 switch (param) { 718 case ISCSI_PARAM_MAX_RECV_DLENGTH: 719 /* TBD */ 720 break; 721 case ISCSI_PARAM_HDRDGST_EN: 722 sscanf(buf, "%d", &value); 723 if (value) { 724 iser_err("DataDigest wasn't negotiated to None\n"); 725 return -EPROTO; 726 } 727 break; 728 case ISCSI_PARAM_DATADGST_EN: 729 sscanf(buf, "%d", &value); 730 if (value) { 731 iser_err("DataDigest wasn't negotiated to None\n"); 732 return -EPROTO; 733 } 734 break; 735 case ISCSI_PARAM_IFMARKER_EN: 736 sscanf(buf, "%d", &value); 737 if (value) { 738 iser_err("IFMarker wasn't negotiated to No\n"); 739 return -EPROTO; 740 } 741 break; 742 case ISCSI_PARAM_OFMARKER_EN: 743 sscanf(buf, "%d", &value); 744 if (value) { 745 iser_err("OFMarker wasn't negotiated to No\n"); 746 return -EPROTO; 747 } 748 break; 749 default: 750 return iscsi_set_param(cls_conn, param, buf, buflen); 751 } 752 753 return 0; 754 } 755 756 /** 757 * iscsi_iser_conn_get_stats() - get iscsi connection statistics 758 * @cls_conn: iscsi class connection 759 * @stats: iscsi stats to output 760 * 761 * Output connection statistics. 762 */ 763 static void 764 iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats) 765 { 766 struct iscsi_conn *conn = cls_conn->dd_data; 767 768 stats->txdata_octets = conn->txdata_octets; 769 stats->rxdata_octets = conn->rxdata_octets; 770 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt; 771 stats->dataout_pdus = conn->dataout_pdus_cnt; 772 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt; 773 stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */ 774 stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */ 775 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt; 776 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt; 777 stats->custom_length = 0; 778 } 779 780 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep, 781 enum iscsi_param param, char *buf) 782 { 783 struct iser_conn *iser_conn = ep->dd_data; 784 785 switch (param) { 786 case ISCSI_PARAM_CONN_PORT: 787 case ISCSI_PARAM_CONN_ADDRESS: 788 if (!iser_conn || !iser_conn->ib_conn.cma_id) 789 return -ENOTCONN; 790 791 return iscsi_conn_get_addr_param((struct sockaddr_storage *) 792 &iser_conn->ib_conn.cma_id->route.addr.dst_addr, 793 param, buf); 794 default: 795 break; 796 } 797 return -ENOSYS; 798 } 799 800 /** 801 * iscsi_iser_ep_connect() - Initiate iSER connection establishment 802 * @shost: scsi_host 803 * @dst_addr: destination address 804 * @non_blocking: indicate if routine can block 805 * 806 * Allocate an iscsi endpoint, an iser_conn structure and bind them. 807 * After that start RDMA connection establishment via rdma_cm. We 808 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown 809 * the endpoint will be destroyed at ep_disconnect while iser_conn will 810 * cleanup its resources asynchronuously. 811 * 812 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error) 813 * if fails. 814 */ 815 static struct iscsi_endpoint * 816 iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr, 817 int non_blocking) 818 { 819 int err; 820 struct iser_conn *iser_conn; 821 struct iscsi_endpoint *ep; 822 823 ep = iscsi_create_endpoint(0); 824 if (!ep) 825 return ERR_PTR(-ENOMEM); 826 827 iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL); 828 if (!iser_conn) { 829 err = -ENOMEM; 830 goto failure; 831 } 832 833 ep->dd_data = iser_conn; 834 iser_conn->ep = ep; 835 iser_conn_init(iser_conn); 836 837 err = iser_connect(iser_conn, NULL, dst_addr, non_blocking); 838 if (err) 839 goto failure; 840 841 return ep; 842 failure: 843 iscsi_destroy_endpoint(ep); 844 return ERR_PTR(err); 845 } 846 847 /** 848 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete 849 * @ep: iscsi endpoint (created at ep_connect) 850 * @timeout_ms: polling timeout allowed in ms. 851 * 852 * This routine boils down to waiting for up_completion signaling 853 * that cma_id got CONNECTED event. 854 * 855 * Return: 1 if succeeded in connection establishment, 0 if timeout expired 856 * (libiscsi will retry will kick in) or -1 if interrupted by signal 857 * or more likely iser connection state transitioned to TEMINATING or 858 * DOWN during the wait period. 859 */ 860 static int 861 iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms) 862 { 863 struct iser_conn *iser_conn = ep->dd_data; 864 int rc; 865 866 rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion, 867 msecs_to_jiffies(timeout_ms)); 868 /* if conn establishment failed, return error code to iscsi */ 869 if (rc == 0) { 870 mutex_lock(&iser_conn->state_mutex); 871 if (iser_conn->state == ISER_CONN_TERMINATING || 872 iser_conn->state == ISER_CONN_DOWN) 873 rc = -1; 874 mutex_unlock(&iser_conn->state_mutex); 875 } 876 877 iser_info("iser conn %p rc = %d\n", iser_conn, rc); 878 879 if (rc > 0) 880 return 1; /* success, this is the equivalent of EPOLLOUT */ 881 else if (!rc) 882 return 0; /* timeout */ 883 else 884 return rc; /* signal */ 885 } 886 887 /** 888 * iscsi_iser_ep_disconnect() - Initiate connection teardown process 889 * @ep: iscsi endpoint handle 890 * 891 * This routine is not blocked by iser and RDMA termination process 892 * completion as we queue a deffered work for iser/RDMA destruction 893 * and cleanup or actually call it immediately in case we didn't pass 894 * iscsi conn bind/start stage, thus it is safe. 895 */ 896 static void 897 iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep) 898 { 899 struct iser_conn *iser_conn = ep->dd_data; 900 901 iser_info("ep %p iser conn %p\n", ep, iser_conn); 902 903 mutex_lock(&iser_conn->state_mutex); 904 iser_conn_terminate(iser_conn); 905 906 /* 907 * if iser_conn and iscsi_conn are bound, we must wait for 908 * iscsi_conn_stop and flush errors completion before freeing 909 * the iser resources. Otherwise we are safe to free resources 910 * immediately. 911 */ 912 if (iser_conn->iscsi_conn) { 913 INIT_WORK(&iser_conn->release_work, iser_release_work); 914 queue_work(release_wq, &iser_conn->release_work); 915 mutex_unlock(&iser_conn->state_mutex); 916 } else { 917 iser_conn->state = ISER_CONN_DOWN; 918 mutex_unlock(&iser_conn->state_mutex); 919 iser_conn_release(iser_conn); 920 } 921 922 iscsi_destroy_endpoint(ep); 923 } 924 925 static umode_t iser_attr_is_visible(int param_type, int param) 926 { 927 switch (param_type) { 928 case ISCSI_HOST_PARAM: 929 switch (param) { 930 case ISCSI_HOST_PARAM_NETDEV_NAME: 931 case ISCSI_HOST_PARAM_HWADDRESS: 932 case ISCSI_HOST_PARAM_INITIATOR_NAME: 933 return S_IRUGO; 934 default: 935 return 0; 936 } 937 case ISCSI_PARAM: 938 switch (param) { 939 case ISCSI_PARAM_MAX_RECV_DLENGTH: 940 case ISCSI_PARAM_MAX_XMIT_DLENGTH: 941 case ISCSI_PARAM_HDRDGST_EN: 942 case ISCSI_PARAM_DATADGST_EN: 943 case ISCSI_PARAM_CONN_ADDRESS: 944 case ISCSI_PARAM_CONN_PORT: 945 case ISCSI_PARAM_EXP_STATSN: 946 case ISCSI_PARAM_PERSISTENT_ADDRESS: 947 case ISCSI_PARAM_PERSISTENT_PORT: 948 case ISCSI_PARAM_PING_TMO: 949 case ISCSI_PARAM_RECV_TMO: 950 case ISCSI_PARAM_INITIAL_R2T_EN: 951 case ISCSI_PARAM_MAX_R2T: 952 case ISCSI_PARAM_IMM_DATA_EN: 953 case ISCSI_PARAM_FIRST_BURST: 954 case ISCSI_PARAM_MAX_BURST: 955 case ISCSI_PARAM_PDU_INORDER_EN: 956 case ISCSI_PARAM_DATASEQ_INORDER_EN: 957 case ISCSI_PARAM_TARGET_NAME: 958 case ISCSI_PARAM_TPGT: 959 case ISCSI_PARAM_USERNAME: 960 case ISCSI_PARAM_PASSWORD: 961 case ISCSI_PARAM_USERNAME_IN: 962 case ISCSI_PARAM_PASSWORD_IN: 963 case ISCSI_PARAM_FAST_ABORT: 964 case ISCSI_PARAM_ABORT_TMO: 965 case ISCSI_PARAM_LU_RESET_TMO: 966 case ISCSI_PARAM_TGT_RESET_TMO: 967 case ISCSI_PARAM_IFACE_NAME: 968 case ISCSI_PARAM_INITIATOR_NAME: 969 case ISCSI_PARAM_DISCOVERY_SESS: 970 return S_IRUGO; 971 default: 972 return 0; 973 } 974 } 975 976 return 0; 977 } 978 979 static struct scsi_host_template iscsi_iser_sht = { 980 .module = THIS_MODULE, 981 .name = "iSCSI Initiator over iSER", 982 .queuecommand = iscsi_queuecommand, 983 .change_queue_depth = scsi_change_queue_depth, 984 .sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE, 985 .cmd_per_lun = ISER_DEF_CMD_PER_LUN, 986 .eh_timed_out = iscsi_eh_cmd_timed_out, 987 .eh_abort_handler = iscsi_eh_abort, 988 .eh_device_reset_handler= iscsi_eh_device_reset, 989 .eh_target_reset_handler = iscsi_eh_recover_target, 990 .target_alloc = iscsi_target_alloc, 991 .proc_name = "iscsi_iser", 992 .this_id = -1, 993 .track_queue_depth = 1, 994 }; 995 996 static struct iscsi_transport iscsi_iser_transport = { 997 .owner = THIS_MODULE, 998 .name = "iser", 999 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO, 1000 /* session management */ 1001 .create_session = iscsi_iser_session_create, 1002 .destroy_session = iscsi_iser_session_destroy, 1003 /* connection management */ 1004 .create_conn = iscsi_iser_conn_create, 1005 .bind_conn = iscsi_iser_conn_bind, 1006 .unbind_conn = iscsi_conn_unbind, 1007 .destroy_conn = iscsi_conn_teardown, 1008 .attr_is_visible = iser_attr_is_visible, 1009 .set_param = iscsi_iser_set_param, 1010 .get_conn_param = iscsi_conn_get_param, 1011 .get_ep_param = iscsi_iser_get_ep_param, 1012 .get_session_param = iscsi_session_get_param, 1013 .start_conn = iscsi_iser_conn_start, 1014 .stop_conn = iscsi_iser_conn_stop, 1015 /* iscsi host params */ 1016 .get_host_param = iscsi_host_get_param, 1017 .set_host_param = iscsi_host_set_param, 1018 /* IO */ 1019 .send_pdu = iscsi_conn_send_pdu, 1020 .get_stats = iscsi_iser_conn_get_stats, 1021 .init_task = iscsi_iser_task_init, 1022 .xmit_task = iscsi_iser_task_xmit, 1023 .cleanup_task = iscsi_iser_cleanup_task, 1024 .alloc_pdu = iscsi_iser_pdu_alloc, 1025 .check_protection = iscsi_iser_check_protection, 1026 /* recovery */ 1027 .session_recovery_timedout = iscsi_session_recovery_timedout, 1028 1029 .ep_connect = iscsi_iser_ep_connect, 1030 .ep_poll = iscsi_iser_ep_poll, 1031 .ep_disconnect = iscsi_iser_ep_disconnect 1032 }; 1033 1034 static int __init iser_init(void) 1035 { 1036 int err; 1037 1038 iser_dbg("Starting iSER datamover...\n"); 1039 1040 memset(&ig, 0, sizeof(struct iser_global)); 1041 1042 ig.desc_cache = kmem_cache_create("iser_descriptors", 1043 sizeof(struct iser_tx_desc), 1044 0, SLAB_HWCACHE_ALIGN, 1045 NULL); 1046 if (ig.desc_cache == NULL) 1047 return -ENOMEM; 1048 1049 /* device init is called only after the first addr resolution */ 1050 mutex_init(&ig.device_list_mutex); 1051 INIT_LIST_HEAD(&ig.device_list); 1052 mutex_init(&ig.connlist_mutex); 1053 INIT_LIST_HEAD(&ig.connlist); 1054 1055 release_wq = alloc_workqueue("release workqueue", 0, 0); 1056 if (!release_wq) { 1057 iser_err("failed to allocate release workqueue\n"); 1058 err = -ENOMEM; 1059 goto err_alloc_wq; 1060 } 1061 1062 iscsi_iser_scsi_transport = iscsi_register_transport( 1063 &iscsi_iser_transport); 1064 if (!iscsi_iser_scsi_transport) { 1065 iser_err("iscsi_register_transport failed\n"); 1066 err = -EINVAL; 1067 goto err_reg; 1068 } 1069 1070 return 0; 1071 1072 err_reg: 1073 destroy_workqueue(release_wq); 1074 err_alloc_wq: 1075 kmem_cache_destroy(ig.desc_cache); 1076 1077 return err; 1078 } 1079 1080 static void __exit iser_exit(void) 1081 { 1082 struct iser_conn *iser_conn, *n; 1083 int connlist_empty; 1084 1085 iser_dbg("Removing iSER datamover...\n"); 1086 destroy_workqueue(release_wq); 1087 1088 mutex_lock(&ig.connlist_mutex); 1089 connlist_empty = list_empty(&ig.connlist); 1090 mutex_unlock(&ig.connlist_mutex); 1091 1092 if (!connlist_empty) { 1093 iser_err("Error cleanup stage completed but we still have iser " 1094 "connections, destroying them anyway\n"); 1095 list_for_each_entry_safe(iser_conn, n, &ig.connlist, 1096 conn_list) { 1097 iser_conn_release(iser_conn); 1098 } 1099 } 1100 1101 iscsi_unregister_transport(&iscsi_iser_transport); 1102 kmem_cache_destroy(ig.desc_cache); 1103 } 1104 1105 module_init(iser_init); 1106 module_exit(iser_exit); 1107