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 77MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover"); 78MODULE_LICENSE("Dual BSD/GPL"); 79MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz"); 80 81static const struct scsi_host_template iscsi_iser_sht; 82static struct iscsi_transport iscsi_iser_transport; 83static struct scsi_transport_template *iscsi_iser_scsi_transport; 84static struct workqueue_struct *release_wq; 85static DEFINE_MUTEX(unbind_iser_conn_mutex); 86struct iser_global ig; 87 88int iser_debug_level = 0; 89module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR); 90MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)"); 91 92static int iscsi_iser_set(const char *val, const struct kernel_param *kp); 93static const struct kernel_param_ops iscsi_iser_size_ops = { 94 .set = iscsi_iser_set, 95 .get = param_get_uint, 96}; 97 98static unsigned int iscsi_max_lun = 512; 99module_param_cb(max_lun, &iscsi_iser_size_ops, &iscsi_max_lun, S_IRUGO); 100MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session, should > 0 (default:512)"); 101 102unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS; 103module_param_cb(max_sectors, &iscsi_iser_size_ops, &iser_max_sectors, 104 S_IRUGO | S_IWUSR); 105MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command, should > 0 (default:1024)"); 106 107bool iser_always_reg = true; 108module_param_named(always_register, iser_always_reg, bool, S_IRUGO); 109MODULE_PARM_DESC(always_register, 110 "Always register memory, even for continuous memory regions (default:true)"); 111 112bool iser_pi_enable = false; 113module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO); 114MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)"); 115 116static int iscsi_iser_set(const char *val, const struct kernel_param *kp) 117{ 118 int ret; 119 unsigned int n = 0; 120 121 ret = kstrtouint(val, 10, &n); 122 if (ret != 0 || n == 0) 123 return -EINVAL; 124 125 return param_set_uint(val, kp); 126} 127 128/* 129 * iscsi_iser_recv() - Process a successful recv completion 130 * @conn: iscsi connection 131 * @hdr: iscsi header 132 * @rx_data: buffer containing receive data payload 133 * @rx_data_len: length of rx_data 134 * 135 * Notes: In case of data length errors or iscsi PDU completion failures 136 * this routine will signal iscsi layer of connection failure. 137 */ 138void iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr, 139 char *rx_data, int rx_data_len) 140{ 141 int rc = 0; 142 int datalen; 143 144 /* verify PDU length */ 145 datalen = ntoh24(hdr->dlength); 146 if (datalen > rx_data_len || (datalen + 4) < rx_data_len) { 147 iser_err("wrong datalen %d (hdr), %d (IB)\n", 148 datalen, rx_data_len); 149 rc = ISCSI_ERR_DATALEN; 150 goto error; 151 } 152 153 if (datalen != rx_data_len) 154 iser_dbg("aligned datalen (%d) hdr, %d (IB)\n", 155 datalen, rx_data_len); 156 157 rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len); 158 if (rc && rc != ISCSI_ERR_NO_SCSI_CMD) 159 goto error; 160 161 return; 162error: 163 iscsi_conn_failure(conn, rc); 164} 165 166/** 167 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU 168 * @task: iscsi task 169 * @opcode: iscsi command opcode 170 * 171 * Netes: This routine can't fail, just assign iscsi task 172 * hdr and max hdr size. 173 */ 174static int iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 175{ 176 struct iscsi_iser_task *iser_task = task->dd_data; 177 178 task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header; 179 task->hdr_max = sizeof(iser_task->desc.iscsi_header); 180 181 return 0; 182} 183 184/** 185 * iser_initialize_task_headers() - Initialize task headers 186 * @task: iscsi task 187 * @tx_desc: iser tx descriptor 188 * 189 * Notes: 190 * This routine may race with iser teardown flow for scsi 191 * error handling TMFs. So for TMF we should acquire the 192 * state mutex to avoid dereferencing the IB device which 193 * may have already been terminated. 194 */ 195int iser_initialize_task_headers(struct iscsi_task *task, 196 struct iser_tx_desc *tx_desc) 197{ 198 struct iser_conn *iser_conn = task->conn->dd_data; 199 struct iser_device *device = iser_conn->ib_conn.device; 200 struct iscsi_iser_task *iser_task = task->dd_data; 201 u64 dma_addr; 202 203 if (unlikely(iser_conn->state != ISER_CONN_UP)) 204 return -ENODEV; 205 206 dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc, 207 ISER_HEADERS_LEN, DMA_TO_DEVICE); 208 if (ib_dma_mapping_error(device->ib_device, dma_addr)) 209 return -ENOMEM; 210 211 tx_desc->inv_wr.next = NULL; 212 tx_desc->reg_wr.wr.next = NULL; 213 tx_desc->mapped = true; 214 tx_desc->dma_addr = dma_addr; 215 tx_desc->tx_sg[0].addr = tx_desc->dma_addr; 216 tx_desc->tx_sg[0].length = ISER_HEADERS_LEN; 217 tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey; 218 219 iser_task->iser_conn = iser_conn; 220 221 return 0; 222} 223 224/** 225 * iscsi_iser_task_init() - Initialize iscsi-iser task 226 * @task: iscsi task 227 * 228 * Initialize the task for the scsi command or mgmt command. 229 * 230 * Return: Returns zero on success or -ENOMEM when failing 231 * to init task headers (dma mapping error). 232 */ 233static int 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 **/ 267static int iscsi_iser_mtask_xmit(struct iscsi_conn *conn, 268 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 285static int iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn, 286 struct iscsi_task *task) 287{ 288 struct iscsi_r2t_info *r2t = &task->unsol_r2t; 289 struct iscsi_data hdr; 290 int error = 0; 291 292 /* Send data-out PDUs while there's still unsolicited data to send */ 293 while (iscsi_task_has_unsol_data(task)) { 294 iscsi_prep_data_out_pdu(task, r2t, &hdr); 295 iser_dbg("Sending data-out: itt 0x%x, data count %d\n", 296 hdr.itt, r2t->data_count); 297 298 /* the buffer description has been passed with the command */ 299 /* Send the command */ 300 error = iser_send_data_out(conn, task, &hdr); 301 if (error) { 302 r2t->datasn--; 303 goto iscsi_iser_task_xmit_unsol_data_exit; 304 } 305 r2t->sent += r2t->data_count; 306 iser_dbg("Need to send %d more as data-out PDUs\n", 307 r2t->data_length - r2t->sent); 308 } 309 310iscsi_iser_task_xmit_unsol_data_exit: 311 return error; 312} 313 314/** 315 * iscsi_iser_task_xmit() - xmit iscsi-iser task 316 * @task: iscsi task 317 * 318 * Return: zero on success or escalates $error on failure. 319 */ 320static int iscsi_iser_task_xmit(struct iscsi_task *task) 321{ 322 struct iscsi_conn *conn = task->conn; 323 struct iscsi_iser_task *iser_task = task->dd_data; 324 int error = 0; 325 326 if (!task->sc) 327 return iscsi_iser_mtask_xmit(conn, task); 328 329 if (task->sc->sc_data_direction == DMA_TO_DEVICE) { 330 BUG_ON(scsi_bufflen(task->sc) == 0); 331 332 iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n", 333 task->itt, scsi_bufflen(task->sc), 334 task->imm_count, task->unsol_r2t.data_length); 335 } 336 337 iser_dbg("ctask xmit [cid %d itt 0x%x]\n", 338 conn->id, task->itt); 339 340 /* Send the cmd PDU */ 341 if (!iser_task->command_sent) { 342 error = iser_send_command(conn, task); 343 if (error) 344 goto iscsi_iser_task_xmit_exit; 345 iser_task->command_sent = 1; 346 } 347 348 /* Send unsolicited data-out PDU(s) if necessary */ 349 if (iscsi_task_has_unsol_data(task)) 350 error = iscsi_iser_task_xmit_unsol_data(conn, task); 351 352 iscsi_iser_task_xmit_exit: 353 return error; 354} 355 356/** 357 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task 358 * @task: iscsi task 359 * 360 * Notes: In case the RDMA device is already NULL (might have 361 * been removed in DEVICE_REMOVAL CM event it will bail-out 362 * without doing dma unmapping. 363 */ 364static void iscsi_iser_cleanup_task(struct iscsi_task *task) 365{ 366 struct iscsi_iser_task *iser_task = task->dd_data; 367 struct iser_tx_desc *tx_desc = &iser_task->desc; 368 struct iser_conn *iser_conn = task->conn->dd_data; 369 struct iser_device *device = iser_conn->ib_conn.device; 370 371 /* DEVICE_REMOVAL event might have already released the device */ 372 if (!device) 373 return; 374 375 if (likely(tx_desc->mapped)) { 376 ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr, 377 ISER_HEADERS_LEN, DMA_TO_DEVICE); 378 tx_desc->mapped = false; 379 } 380 381 /* mgmt tasks do not need special cleanup */ 382 if (!task->sc) 383 return; 384 385 if (iser_task->status == ISER_TASK_STATUS_STARTED) { 386 iser_task->status = ISER_TASK_STATUS_COMPLETED; 387 iser_task_rdma_finalize(iser_task); 388 } 389} 390 391/** 392 * iscsi_iser_check_protection() - check protection information status of task. 393 * @task: iscsi task 394 * @sector: error sector if exsists (output) 395 * 396 * Return: zero if no data-integrity errors have occured 397 * 0x1: data-integrity error occured in the guard-block 398 * 0x2: data-integrity error occured in the reference tag 399 * 0x3: data-integrity error occured in the application tag 400 * 401 * In addition the error sector is marked. 402 */ 403static u8 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector) 404{ 405 struct iscsi_iser_task *iser_task = task->dd_data; 406 enum iser_data_dir dir = iser_task->dir[ISER_DIR_IN] ? 407 ISER_DIR_IN : ISER_DIR_OUT; 408 409 return iser_check_task_pi_status(iser_task, dir, sector); 410} 411 412/** 413 * iscsi_iser_conn_create() - create a new iscsi-iser connection 414 * @cls_session: iscsi class connection 415 * @conn_idx: connection index within the session (for MCS) 416 * 417 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL 418 * otherwise. 419 */ 420static struct iscsi_cls_conn * 421iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, 422 uint32_t conn_idx) 423{ 424 struct iscsi_conn *conn; 425 struct iscsi_cls_conn *cls_conn; 426 427 cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx); 428 if (!cls_conn) 429 return NULL; 430 conn = cls_conn->dd_data; 431 432 /* 433 * due to issues with the login code re iser sematics 434 * this not set in iscsi_conn_setup - FIXME 435 */ 436 conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN; 437 438 return cls_conn; 439} 440 441/** 442 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures 443 * @cls_session: iscsi class session 444 * @cls_conn: iscsi class connection 445 * @transport_eph: transport end-point handle 446 * @is_leading: indicate if this is the session leading connection (MCS) 447 * 448 * Return: zero on success, $error if iscsi_conn_bind fails and 449 * -EINVAL in case end-point doesn't exists anymore or iser connection 450 * state is not UP (teardown already started). 451 */ 452static int iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session, 453 struct iscsi_cls_conn *cls_conn, 454 uint64_t transport_eph, int is_leading) 455{ 456 struct iscsi_conn *conn = cls_conn->dd_data; 457 struct iser_conn *iser_conn; 458 struct iscsi_endpoint *ep; 459 int error; 460 461 error = iscsi_conn_bind(cls_session, cls_conn, is_leading); 462 if (error) 463 return error; 464 465 /* the transport ep handle comes from user space so it must be 466 * verified against the global ib connections list */ 467 ep = iscsi_lookup_endpoint(transport_eph); 468 if (!ep) { 469 iser_err("can't bind eph %llx\n", 470 (unsigned long long)transport_eph); 471 return -EINVAL; 472 } 473 iser_conn = ep->dd_data; 474 475 mutex_lock(&iser_conn->state_mutex); 476 if (iser_conn->state != ISER_CONN_UP) { 477 error = -EINVAL; 478 iser_err("iser_conn %p state is %d, teardown started\n", 479 iser_conn, iser_conn->state); 480 goto out; 481 } 482 483 error = iser_alloc_rx_descriptors(iser_conn, conn->session); 484 if (error) 485 goto out; 486 487 /* binds the iSER connection retrieved from the previously 488 * connected ep_handle to the iSCSI layer connection. exchanges 489 * connection pointers */ 490 iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn); 491 492 conn->dd_data = iser_conn; 493 iser_conn->iscsi_conn = conn; 494 495out: 496 iscsi_put_endpoint(ep); 497 mutex_unlock(&iser_conn->state_mutex); 498 return error; 499} 500 501/** 502 * iscsi_iser_conn_start() - start iscsi-iser connection 503 * @cls_conn: iscsi class connection 504 * 505 * Notes: Here iser intialize (or re-initialize) stop_completion as 506 * from this point iscsi must call conn_stop in session/connection 507 * teardown so iser transport must wait for it. 508 */ 509static int iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn) 510{ 511 struct iscsi_conn *iscsi_conn; 512 struct iser_conn *iser_conn; 513 514 iscsi_conn = cls_conn->dd_data; 515 iser_conn = iscsi_conn->dd_data; 516 reinit_completion(&iser_conn->stop_completion); 517 518 return iscsi_conn_start(cls_conn); 519} 520 521/** 522 * iscsi_iser_conn_stop() - stop iscsi-iser connection 523 * @cls_conn: iscsi class connection 524 * @flag: indicate if recover or terminate (passed as is) 525 * 526 * Notes: Calling iscsi_conn_stop might theoretically race with 527 * DEVICE_REMOVAL event and dereference a previously freed RDMA device 528 * handle, so we call it under iser the state lock to protect against 529 * this kind of race. 530 */ 531static void iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 532{ 533 struct iscsi_conn *conn = cls_conn->dd_data; 534 struct iser_conn *iser_conn = conn->dd_data; 535 536 iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn); 537 538 /* 539 * Userspace may have goofed up and not bound the connection or 540 * might have only partially setup the connection. 541 */ 542 if (iser_conn) { 543 mutex_lock(&iser_conn->state_mutex); 544 mutex_lock(&unbind_iser_conn_mutex); 545 iser_conn_terminate(iser_conn); 546 iscsi_conn_stop(cls_conn, flag); 547 548 /* unbind */ 549 iser_conn->iscsi_conn = NULL; 550 conn->dd_data = NULL; 551 mutex_unlock(&unbind_iser_conn_mutex); 552 553 complete(&iser_conn->stop_completion); 554 mutex_unlock(&iser_conn->state_mutex); 555 } else { 556 iscsi_conn_stop(cls_conn, flag); 557 } 558} 559 560/** 561 * iscsi_iser_session_destroy() - destroy iscsi-iser session 562 * @cls_session: iscsi class session 563 * 564 * Removes and free iscsi host. 565 */ 566static void iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session) 567{ 568 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 569 570 iscsi_session_teardown(cls_session); 571 iscsi_host_remove(shost, false); 572 iscsi_host_free(shost); 573} 574 575static inline unsigned int iser_dif_prot_caps(int prot_caps) 576{ 577 int ret = 0; 578 579 if (prot_caps & IB_PROT_T10DIF_TYPE_1) 580 ret |= SHOST_DIF_TYPE1_PROTECTION | 581 SHOST_DIX_TYPE0_PROTECTION | 582 SHOST_DIX_TYPE1_PROTECTION; 583 if (prot_caps & IB_PROT_T10DIF_TYPE_2) 584 ret |= SHOST_DIF_TYPE2_PROTECTION | 585 SHOST_DIX_TYPE2_PROTECTION; 586 if (prot_caps & IB_PROT_T10DIF_TYPE_3) 587 ret |= SHOST_DIF_TYPE3_PROTECTION | 588 SHOST_DIX_TYPE3_PROTECTION; 589 590 return ret; 591} 592 593/** 594 * iscsi_iser_session_create() - create an iscsi-iser session 595 * @ep: iscsi end-point handle 596 * @cmds_max: maximum commands in this session 597 * @qdepth: session command queue depth 598 * @initial_cmdsn: initiator command sequnce number 599 * 600 * Allocates and adds a scsi host, expose DIF supprot if 601 * exists, and sets up an iscsi session. 602 */ 603static struct iscsi_cls_session * 604iscsi_iser_session_create(struct iscsi_endpoint *ep, 605 uint16_t cmds_max, uint16_t qdepth, 606 uint32_t initial_cmdsn) 607{ 608 struct iscsi_cls_session *cls_session; 609 struct Scsi_Host *shost; 610 struct iser_conn *iser_conn = NULL; 611 struct ib_conn *ib_conn; 612 struct ib_device *ib_dev; 613 u32 max_fr_sectors; 614 615 shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0); 616 if (!shost) 617 return NULL; 618 shost->transportt = iscsi_iser_scsi_transport; 619 shost->cmd_per_lun = qdepth; 620 shost->max_lun = iscsi_max_lun; 621 shost->max_id = 0; 622 shost->max_channel = 0; 623 shost->max_cmd_len = 16; 624 625 /* 626 * older userspace tools (before 2.0-870) did not pass us 627 * the leading conn's ep so this will be NULL; 628 */ 629 if (ep) { 630 iser_conn = ep->dd_data; 631 shost->sg_tablesize = iser_conn->scsi_sg_tablesize; 632 shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds); 633 634 mutex_lock(&iser_conn->state_mutex); 635 if (iser_conn->state != ISER_CONN_UP) { 636 iser_err("iser conn %p already started teardown\n", 637 iser_conn); 638 mutex_unlock(&iser_conn->state_mutex); 639 goto free_host; 640 } 641 642 ib_conn = &iser_conn->ib_conn; 643 ib_dev = ib_conn->device->ib_device; 644 if (ib_conn->pi_support) { 645 u32 sig_caps = ib_dev->attrs.sig_prot_cap; 646 647 shost->sg_prot_tablesize = shost->sg_tablesize; 648 scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps)); 649 scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP | 650 SHOST_DIX_GUARD_CRC); 651 } 652 653 if (!(ib_dev->attrs.kernel_cap_flags & IBK_SG_GAPS_REG)) 654 shost->virt_boundary_mask = SZ_4K - 1; 655 656 if (iscsi_host_add(shost, ib_dev->dev.parent)) { 657 mutex_unlock(&iser_conn->state_mutex); 658 goto free_host; 659 } 660 mutex_unlock(&iser_conn->state_mutex); 661 } else { 662 shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX); 663 if (iscsi_host_add(shost, NULL)) 664 goto free_host; 665 } 666 667 max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9; 668 shost->max_sectors = min(iser_max_sectors, max_fr_sectors); 669 670 iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n", 671 iser_conn, shost->sg_tablesize, 672 shost->max_sectors); 673 674 if (shost->max_sectors < iser_max_sectors) 675 iser_warn("max_sectors was reduced from %u to %u\n", 676 iser_max_sectors, shost->max_sectors); 677 678 cls_session = iscsi_session_setup(&iscsi_iser_transport, shost, 679 shost->can_queue, 0, 680 sizeof(struct iscsi_iser_task), 681 initial_cmdsn, 0); 682 if (!cls_session) 683 goto remove_host; 684 685 return cls_session; 686 687remove_host: 688 iscsi_host_remove(shost, false); 689free_host: 690 iscsi_host_free(shost); 691 return NULL; 692} 693 694static int 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_conn_get_stats() - get iscsi connection statistics 740 * @cls_conn: iscsi class connection 741 * @stats: iscsi stats to output 742 * 743 * Output connection statistics. 744 */ 745static void iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, 746 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 762static 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 */ 797static struct iscsi_endpoint *iscsi_iser_ep_connect(struct Scsi_Host *shost, 798 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; 824failure: 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 */ 842static int iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms) 843{ 844 struct iser_conn *iser_conn = ep->dd_data; 845 int rc; 846 847 rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion, 848 msecs_to_jiffies(timeout_ms)); 849 /* if conn establishment failed, return error code to iscsi */ 850 if (rc == 0) { 851 mutex_lock(&iser_conn->state_mutex); 852 if (iser_conn->state == ISER_CONN_TERMINATING || 853 iser_conn->state == ISER_CONN_DOWN) 854 rc = -1; 855 mutex_unlock(&iser_conn->state_mutex); 856 } 857 858 iser_info("iser conn %p rc = %d\n", iser_conn, rc); 859 860 if (rc > 0) 861 return 1; /* success, this is the equivalent of EPOLLOUT */ 862 else if (!rc) 863 return 0; /* timeout */ 864 else 865 return rc; /* signal */ 866} 867 868/** 869 * iscsi_iser_ep_disconnect() - Initiate connection teardown process 870 * @ep: iscsi endpoint handle 871 * 872 * This routine is not blocked by iser and RDMA termination process 873 * completion as we queue a deffered work for iser/RDMA destruction 874 * and cleanup or actually call it immediately in case we didn't pass 875 * iscsi conn bind/start stage, thus it is safe. 876 */ 877static void iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep) 878{ 879 struct iser_conn *iser_conn = ep->dd_data; 880 881 iser_info("ep %p iser conn %p\n", ep, iser_conn); 882 883 mutex_lock(&iser_conn->state_mutex); 884 iser_conn_terminate(iser_conn); 885 886 /* 887 * if iser_conn and iscsi_conn are bound, we must wait for 888 * iscsi_conn_stop and flush errors completion before freeing 889 * the iser resources. Otherwise we are safe to free resources 890 * immediately. 891 */ 892 if (iser_conn->iscsi_conn) { 893 INIT_WORK(&iser_conn->release_work, iser_release_work); 894 queue_work(release_wq, &iser_conn->release_work); 895 mutex_unlock(&iser_conn->state_mutex); 896 } else { 897 iser_conn->state = ISER_CONN_DOWN; 898 mutex_unlock(&iser_conn->state_mutex); 899 iser_conn_release(iser_conn); 900 } 901 902 iscsi_destroy_endpoint(ep); 903} 904 905static umode_t iser_attr_is_visible(int param_type, int param) 906{ 907 switch (param_type) { 908 case ISCSI_HOST_PARAM: 909 switch (param) { 910 case ISCSI_HOST_PARAM_NETDEV_NAME: 911 case ISCSI_HOST_PARAM_HWADDRESS: 912 case ISCSI_HOST_PARAM_INITIATOR_NAME: 913 return S_IRUGO; 914 default: 915 return 0; 916 } 917 case ISCSI_PARAM: 918 switch (param) { 919 case ISCSI_PARAM_MAX_RECV_DLENGTH: 920 case ISCSI_PARAM_MAX_XMIT_DLENGTH: 921 case ISCSI_PARAM_HDRDGST_EN: 922 case ISCSI_PARAM_DATADGST_EN: 923 case ISCSI_PARAM_CONN_ADDRESS: 924 case ISCSI_PARAM_CONN_PORT: 925 case ISCSI_PARAM_EXP_STATSN: 926 case ISCSI_PARAM_PERSISTENT_ADDRESS: 927 case ISCSI_PARAM_PERSISTENT_PORT: 928 case ISCSI_PARAM_PING_TMO: 929 case ISCSI_PARAM_RECV_TMO: 930 case ISCSI_PARAM_INITIAL_R2T_EN: 931 case ISCSI_PARAM_MAX_R2T: 932 case ISCSI_PARAM_IMM_DATA_EN: 933 case ISCSI_PARAM_FIRST_BURST: 934 case ISCSI_PARAM_MAX_BURST: 935 case ISCSI_PARAM_PDU_INORDER_EN: 936 case ISCSI_PARAM_DATASEQ_INORDER_EN: 937 case ISCSI_PARAM_TARGET_NAME: 938 case ISCSI_PARAM_TPGT: 939 case ISCSI_PARAM_USERNAME: 940 case ISCSI_PARAM_PASSWORD: 941 case ISCSI_PARAM_USERNAME_IN: 942 case ISCSI_PARAM_PASSWORD_IN: 943 case ISCSI_PARAM_FAST_ABORT: 944 case ISCSI_PARAM_ABORT_TMO: 945 case ISCSI_PARAM_LU_RESET_TMO: 946 case ISCSI_PARAM_TGT_RESET_TMO: 947 case ISCSI_PARAM_IFACE_NAME: 948 case ISCSI_PARAM_INITIATOR_NAME: 949 case ISCSI_PARAM_DISCOVERY_SESS: 950 return S_IRUGO; 951 default: 952 return 0; 953 } 954 } 955 956 return 0; 957} 958 959static const struct scsi_host_template iscsi_iser_sht = { 960 .module = THIS_MODULE, 961 .name = "iSCSI Initiator over iSER", 962 .queuecommand = iscsi_queuecommand, 963 .change_queue_depth = scsi_change_queue_depth, 964 .sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE, 965 .cmd_per_lun = ISER_DEF_CMD_PER_LUN, 966 .eh_timed_out = iscsi_eh_cmd_timed_out, 967 .eh_abort_handler = iscsi_eh_abort, 968 .eh_device_reset_handler= iscsi_eh_device_reset, 969 .eh_target_reset_handler = iscsi_eh_recover_target, 970 .target_alloc = iscsi_target_alloc, 971 .proc_name = "iscsi_iser", 972 .this_id = -1, 973 .track_queue_depth = 1, 974 .cmd_size = sizeof(struct iscsi_cmd), 975}; 976 977static struct iscsi_transport iscsi_iser_transport = { 978 .owner = THIS_MODULE, 979 .name = "iser", 980 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO, 981 /* session management */ 982 .create_session = iscsi_iser_session_create, 983 .destroy_session = iscsi_iser_session_destroy, 984 /* connection management */ 985 .create_conn = iscsi_iser_conn_create, 986 .bind_conn = iscsi_iser_conn_bind, 987 .unbind_conn = iscsi_conn_unbind, 988 .destroy_conn = iscsi_conn_teardown, 989 .attr_is_visible = iser_attr_is_visible, 990 .set_param = iscsi_iser_set_param, 991 .get_conn_param = iscsi_conn_get_param, 992 .get_ep_param = iscsi_iser_get_ep_param, 993 .get_session_param = iscsi_session_get_param, 994 .start_conn = iscsi_iser_conn_start, 995 .stop_conn = iscsi_iser_conn_stop, 996 /* iscsi host params */ 997 .get_host_param = iscsi_host_get_param, 998 .set_host_param = iscsi_host_set_param, 999 /* IO */ 1000 .send_pdu = iscsi_conn_send_pdu, 1001 .get_stats = iscsi_iser_conn_get_stats, 1002 .init_task = iscsi_iser_task_init, 1003 .xmit_task = iscsi_iser_task_xmit, 1004 .cleanup_task = iscsi_iser_cleanup_task, 1005 .alloc_pdu = iscsi_iser_pdu_alloc, 1006 .check_protection = iscsi_iser_check_protection, 1007 /* recovery */ 1008 .session_recovery_timedout = iscsi_session_recovery_timedout, 1009 1010 .ep_connect = iscsi_iser_ep_connect, 1011 .ep_poll = iscsi_iser_ep_poll, 1012 .ep_disconnect = iscsi_iser_ep_disconnect 1013}; 1014 1015static int __init iser_init(void) 1016{ 1017 int err; 1018 1019 iser_dbg("Starting iSER datamover...\n"); 1020 1021 memset(&ig, 0, sizeof(struct iser_global)); 1022 1023 ig.desc_cache = kmem_cache_create("iser_descriptors", 1024 sizeof(struct iser_tx_desc), 1025 0, SLAB_HWCACHE_ALIGN, 1026 NULL); 1027 if (ig.desc_cache == NULL) 1028 return -ENOMEM; 1029 1030 /* device init is called only after the first addr resolution */ 1031 mutex_init(&ig.device_list_mutex); 1032 INIT_LIST_HEAD(&ig.device_list); 1033 mutex_init(&ig.connlist_mutex); 1034 INIT_LIST_HEAD(&ig.connlist); 1035 1036 release_wq = alloc_workqueue("release workqueue", 0, 0); 1037 if (!release_wq) { 1038 iser_err("failed to allocate release workqueue\n"); 1039 err = -ENOMEM; 1040 goto err_alloc_wq; 1041 } 1042 1043 iscsi_iser_scsi_transport = iscsi_register_transport( 1044 &iscsi_iser_transport); 1045 if (!iscsi_iser_scsi_transport) { 1046 iser_err("iscsi_register_transport failed\n"); 1047 err = -EINVAL; 1048 goto err_reg; 1049 } 1050 1051 return 0; 1052 1053err_reg: 1054 destroy_workqueue(release_wq); 1055err_alloc_wq: 1056 kmem_cache_destroy(ig.desc_cache); 1057 1058 return err; 1059} 1060 1061static void __exit iser_exit(void) 1062{ 1063 struct iser_conn *iser_conn, *n; 1064 int connlist_empty; 1065 1066 iser_dbg("Removing iSER datamover...\n"); 1067 destroy_workqueue(release_wq); 1068 1069 mutex_lock(&ig.connlist_mutex); 1070 connlist_empty = list_empty(&ig.connlist); 1071 mutex_unlock(&ig.connlist_mutex); 1072 1073 if (!connlist_empty) { 1074 iser_err("Error cleanup stage completed but we still have iser " 1075 "connections, destroying them anyway\n"); 1076 list_for_each_entry_safe(iser_conn, n, &ig.connlist, 1077 conn_list) { 1078 iser_conn_release(iser_conn); 1079 } 1080 } 1081 1082 iscsi_unregister_transport(&iscsi_iser_transport); 1083 kmem_cache_destroy(ig.desc_cache); 1084} 1085 1086module_init(iser_init); 1087module_exit(iser_exit); 1088