drivers/infiniband/ulp/iser/iscsi

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This source file includes following definitions.
iscsi_iser_recv
iscsi_iser_pdu_alloc
iser_initialize_task_headers
iscsi_iser_task_init
iscsi_iser_mtask_xmit
iscsi_iser_task_xmit_unsol_data
iscsi_iser_task_xmit
iscsi_iser_cleanup_task
iscsi_iser_check_protection
iscsi_iser_conn_create
iscsi_iser_conn_bind
iscsi_iser_conn_start
iscsi_iser_conn_stop
iscsi_iser_session_destroy
iser_dif_prot_caps
iscsi_iser_session_create
iscsi_iser_set_param
iscsi_iser_conn_get_stats
iscsi_iser_get_ep_param
iscsi_iser_ep_connect
iscsi_iser_ep_poll
iscsi_iser_ep_disconnect
iser_attr_is_visible
iser_init
iser_exit
   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->inv_wr.next = NULL;
 209         tx_desc->reg_wr.wr.next = NULL;
 210         tx_desc->mapped = true;
 211         tx_desc->dma_addr = dma_addr;
 212         tx_desc->tx_sg[0].addr   = tx_desc->dma_addr;
 213         tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
 214         tx_desc->tx_sg[0].lkey   = device->pd->local_dma_lkey;
 215 
 216         iser_task->iser_conn = iser_conn;
 217 out:
 218         if (unlikely(mgmt_task))
 219                 mutex_unlock(&iser_conn->state_mutex);
 220 
 221         return ret;
 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  */
 233 static int
 234 iscsi_iser_task_init(struct iscsi_task *task)
 235 {
 236         struct iscsi_iser_task *iser_task = task->dd_data;
 237         int ret;
 238 
 239         ret = iser_initialize_task_headers(task, &iser_task->desc);
 240         if (ret) {
 241                 iser_err("Failed to init task %p, err = %d\n",
 242                          iser_task, ret);
 243                 return ret;
 244         }
 245 
 246         /* mgmt task */
 247         if (!task->sc)
 248                 return 0;
 249 
 250         iser_task->command_sent = 0;
 251         iser_task_rdma_init(iser_task);
 252         iser_task->sc = task->sc;
 253 
 254         return 0;
 255 }
 256 
 257 /**
 258  * iscsi_iser_mtask_xmit() - xmit management (immediate) task
 259  * @conn: iscsi connection
 260  * @task: task management task
 261  *
 262  * Notes:
 263  *      The function can return -EAGAIN in which case caller must
 264  *      call it again later, or recover. '0' return code means successful
 265  *      xmit.
 266  *
 267  **/
 268 static int
 269 iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task)
 270 {
 271         int error = 0;
 272 
 273         iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
 274 
 275         error = iser_send_control(conn, task);
 276 
 277         /* since iser xmits control with zero copy, tasks can not be recycled
 278          * right after sending them.
 279          * The recycling scheme is based on whether a response is expected
 280          * - if yes, the task is recycled at iscsi_complete_pdu
 281          * - if no,  the task is recycled at iser_snd_completion
 282          */
 283         return error;
 284 }
 285 
 286 static int
 287 iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
 288                                  struct iscsi_task *task)
 289 {
 290         struct iscsi_r2t_info *r2t = &task->unsol_r2t;
 291         struct iscsi_data hdr;
 292         int error = 0;
 293 
 294         /* Send data-out PDUs while there's still unsolicited data to send */
 295         while (iscsi_task_has_unsol_data(task)) {
 296                 iscsi_prep_data_out_pdu(task, r2t, &hdr);
 297                 iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
 298                            hdr.itt, r2t->data_count);
 299 
 300                 /* the buffer description has been passed with the command */
 301                 /* Send the command */
 302                 error = iser_send_data_out(conn, task, &hdr);
 303                 if (error) {
 304                         r2t->datasn--;
 305                         goto iscsi_iser_task_xmit_unsol_data_exit;
 306                 }
 307                 r2t->sent += r2t->data_count;
 308                 iser_dbg("Need to send %d more as data-out PDUs\n",
 309                            r2t->data_length - r2t->sent);
 310         }
 311 
 312 iscsi_iser_task_xmit_unsol_data_exit:
 313         return error;
 314 }
 315 
 316 /**
 317  * iscsi_iser_task_xmit() - xmit iscsi-iser task
 318  * @task: iscsi task
 319  *
 320  * Return: zero on success or escalates $error on failure.
 321  */
 322 static int
 323 iscsi_iser_task_xmit(struct iscsi_task *task)
 324 {
 325         struct iscsi_conn *conn = task->conn;
 326         struct iscsi_iser_task *iser_task = task->dd_data;
 327         int error = 0;
 328 
 329         if (!task->sc)
 330                 return iscsi_iser_mtask_xmit(conn, task);
 331 
 332         if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
 333                 BUG_ON(scsi_bufflen(task->sc) == 0);
 334 
 335                 iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
 336                            task->itt, scsi_bufflen(task->sc),
 337                            task->imm_count, task->unsol_r2t.data_length);
 338         }
 339 
 340         iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
 341                    conn->id, task->itt);
 342 
 343         /* Send the cmd PDU */
 344         if (!iser_task->command_sent) {
 345                 error = iser_send_command(conn, task);
 346                 if (error)
 347                         goto iscsi_iser_task_xmit_exit;
 348                 iser_task->command_sent = 1;
 349         }
 350 
 351         /* Send unsolicited data-out PDU(s) if necessary */
 352         if (iscsi_task_has_unsol_data(task))
 353                 error = iscsi_iser_task_xmit_unsol_data(conn, task);
 354 
 355  iscsi_iser_task_xmit_exit:
 356         return error;
 357 }
 358 
 359 /**
 360  * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task
 361  * @task: iscsi task
 362  *
 363  * Notes: In case the RDMA device is already NULL (might have
 364  *        been removed in DEVICE_REMOVAL CM event it will bail-out
 365  *        without doing dma unmapping.
 366  */
 367 static void iscsi_iser_cleanup_task(struct iscsi_task *task)
 368 {
 369         struct iscsi_iser_task *iser_task = task->dd_data;
 370         struct iser_tx_desc *tx_desc = &iser_task->desc;
 371         struct iser_conn *iser_conn = task->conn->dd_data;
 372         struct iser_device *device = iser_conn->ib_conn.device;
 373 
 374         /* DEVICE_REMOVAL event might have already released the device */
 375         if (!device)
 376                 return;
 377 
 378         if (likely(tx_desc->mapped)) {
 379                 ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
 380                                     ISER_HEADERS_LEN, DMA_TO_DEVICE);
 381                 tx_desc->mapped = false;
 382         }
 383 
 384         /* mgmt tasks do not need special cleanup */
 385         if (!task->sc)
 386                 return;
 387 
 388         if (iser_task->status == ISER_TASK_STATUS_STARTED) {
 389                 iser_task->status = ISER_TASK_STATUS_COMPLETED;
 390                 iser_task_rdma_finalize(iser_task);
 391         }
 392 }
 393 
 394 /**
 395  * iscsi_iser_check_protection() - check protection information status of task.
 396  * @task:     iscsi task
 397  * @sector:   error sector if exsists (output)
 398  *
 399  * Return: zero if no data-integrity errors have occured
 400  *         0x1: data-integrity error occured in the guard-block
 401  *         0x2: data-integrity error occured in the reference tag
 402  *         0x3: data-integrity error occured in the application tag
 403  *
 404  *         In addition the error sector is marked.
 405  */
 406 static u8
 407 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector)
 408 {
 409         struct iscsi_iser_task *iser_task = task->dd_data;
 410         enum iser_data_dir dir = iser_task->dir[ISER_DIR_IN] ?
 411                                         ISER_DIR_IN : ISER_DIR_OUT;
 412 
 413         return iser_check_task_pi_status(iser_task, dir, sector);
 414 }
 415 
 416 /**
 417  * iscsi_iser_conn_create() - create a new iscsi-iser connection
 418  * @cls_session: iscsi class connection
 419  * @conn_idx:    connection index within the session (for MCS)
 420  *
 421  * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL
 422  *         otherwise.
 423  */
 424 static struct iscsi_cls_conn *
 425 iscsi_iser_conn_create(struct iscsi_cls_session *cls_session,
 426                        uint32_t conn_idx)
 427 {
 428         struct iscsi_conn *conn;
 429         struct iscsi_cls_conn *cls_conn;
 430 
 431         cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx);
 432         if (!cls_conn)
 433                 return NULL;
 434         conn = cls_conn->dd_data;
 435 
 436         /*
 437          * due to issues with the login code re iser sematics
 438          * this not set in iscsi_conn_setup - FIXME
 439          */
 440         conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
 441 
 442         return cls_conn;
 443 }
 444 
 445 /**
 446  * iscsi_iser_conn_bind() - bind iscsi and iser connection structures
 447  * @cls_session:     iscsi class session
 448  * @cls_conn:        iscsi class connection
 449  * @transport_eph:   transport end-point handle
 450  * @is_leading:      indicate if this is the session leading connection (MCS)
 451  *
 452  * Return: zero on success, $error if iscsi_conn_bind fails and
 453  *         -EINVAL in case end-point doesn't exsits anymore or iser connection
 454  *         state is not UP (teardown already started).
 455  */
 456 static int
 457 iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
 458                      struct iscsi_cls_conn *cls_conn,
 459                      uint64_t transport_eph,
 460                      int is_leading)
 461 {
 462         struct iscsi_conn *conn = cls_conn->dd_data;
 463         struct iser_conn *iser_conn;
 464         struct iscsi_endpoint *ep;
 465         int error;
 466 
 467         error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
 468         if (error)
 469                 return error;
 470 
 471         /* the transport ep handle comes from user space so it must be
 472          * verified against the global ib connections list */
 473         ep = iscsi_lookup_endpoint(transport_eph);
 474         if (!ep) {
 475                 iser_err("can't bind eph %llx\n",
 476                          (unsigned long long)transport_eph);
 477                 return -EINVAL;
 478         }
 479         iser_conn = ep->dd_data;
 480 
 481         mutex_lock(&iser_conn->state_mutex);
 482         if (iser_conn->state != ISER_CONN_UP) {
 483                 error = -EINVAL;
 484                 iser_err("iser_conn %p state is %d, teardown started\n",
 485                          iser_conn, iser_conn->state);
 486                 goto out;
 487         }
 488 
 489         error = iser_alloc_rx_descriptors(iser_conn, conn->session);
 490         if (error)
 491                 goto out;
 492 
 493         /* binds the iSER connection retrieved from the previously
 494          * connected ep_handle to the iSCSI layer connection. exchanges
 495          * connection pointers */
 496         iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn);
 497 
 498         conn->dd_data = iser_conn;
 499         iser_conn->iscsi_conn = conn;
 500 
 501 out:
 502         mutex_unlock(&iser_conn->state_mutex);
 503         return error;
 504 }
 505 
 506 /**
 507  * iscsi_iser_conn_start() - start iscsi-iser connection
 508  * @cls_conn: iscsi class connection
 509  *
 510  * Notes: Here iser intialize (or re-initialize) stop_completion as
 511  *        from this point iscsi must call conn_stop in session/connection
 512  *        teardown so iser transport must wait for it.
 513  */
 514 static int
 515 iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
 516 {
 517         struct iscsi_conn *iscsi_conn;
 518         struct iser_conn *iser_conn;
 519 
 520         iscsi_conn = cls_conn->dd_data;
 521         iser_conn = iscsi_conn->dd_data;
 522         reinit_completion(&iser_conn->stop_completion);
 523 
 524         return iscsi_conn_start(cls_conn);
 525 }
 526 
 527 /**
 528  * iscsi_iser_conn_stop() - stop iscsi-iser connection
 529  * @cls_conn:  iscsi class connection
 530  * @flag:      indicate if recover or terminate (passed as is)
 531  *
 532  * Notes: Calling iscsi_conn_stop might theoretically race with
 533  *        DEVICE_REMOVAL event and dereference a previously freed RDMA device
 534  *        handle, so we call it under iser the state lock to protect against
 535  *        this kind of race.
 536  */
 537 static void
 538 iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 539 {
 540         struct iscsi_conn *conn = cls_conn->dd_data;
 541         struct iser_conn *iser_conn = conn->dd_data;
 542 
 543         iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn);
 544 
 545         /*
 546          * Userspace may have goofed up and not bound the connection or
 547          * might have only partially setup the connection.
 548          */
 549         if (iser_conn) {
 550                 mutex_lock(&iser_conn->state_mutex);
 551                 mutex_lock(&unbind_iser_conn_mutex);
 552                 iser_conn_terminate(iser_conn);
 553                 iscsi_conn_stop(cls_conn, flag);
 554 
 555                 /* unbind */
 556                 iser_conn->iscsi_conn = NULL;
 557                 conn->dd_data = NULL;
 558                 mutex_unlock(&unbind_iser_conn_mutex);
 559 
 560                 complete(&iser_conn->stop_completion);
 561                 mutex_unlock(&iser_conn->state_mutex);
 562         } else {
 563                 iscsi_conn_stop(cls_conn, flag);
 564         }
 565 }
 566 
 567 /**
 568  * iscsi_iser_session_destroy() - destroy iscsi-iser session
 569  * @cls_session: iscsi class session
 570  *
 571  * Removes and free iscsi host.
 572  */
 573 static void
 574 iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
 575 {
 576         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 577 
 578         iscsi_session_teardown(cls_session);
 579         iscsi_host_remove(shost);
 580         iscsi_host_free(shost);
 581 }
 582 
 583 static inline unsigned int
 584 iser_dif_prot_caps(int prot_caps)
 585 {
 586         return ((prot_caps & IB_PROT_T10DIF_TYPE_1) ?
 587                 SHOST_DIF_TYPE1_PROTECTION | SHOST_DIX_TYPE0_PROTECTION |
 588                 SHOST_DIX_TYPE1_PROTECTION : 0) |
 589                ((prot_caps & IB_PROT_T10DIF_TYPE_2) ?
 590                 SHOST_DIF_TYPE2_PROTECTION | SHOST_DIX_TYPE2_PROTECTION : 0) |
 591                ((prot_caps & IB_PROT_T10DIF_TYPE_3) ?
 592                 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE3_PROTECTION : 0);
 593 }
 594 
 595 /**
 596  * iscsi_iser_session_create() - create an iscsi-iser session
 597  * @ep:             iscsi end-point handle
 598  * @cmds_max:       maximum commands in this session
 599  * @qdepth:         session command queue depth
 600  * @initial_cmdsn:  initiator command sequnce number
 601  *
 602  * Allocates and adds a scsi host, expose DIF supprot if
 603  * exists, and sets up an iscsi session.
 604  */
 605 static struct iscsi_cls_session *
 606 iscsi_iser_session_create(struct iscsi_endpoint *ep,
 607                           uint16_t cmds_max, uint16_t qdepth,
 608                           uint32_t initial_cmdsn)
 609 {
 610         struct iscsi_cls_session *cls_session;
 611         struct Scsi_Host *shost;
 612         struct iser_conn *iser_conn = NULL;
 613         struct ib_conn *ib_conn;
 614         struct ib_device *ib_dev;
 615         u32 max_fr_sectors;
 616 
 617         shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
 618         if (!shost)
 619                 return NULL;
 620         shost->transportt = iscsi_iser_scsi_transport;
 621         shost->cmd_per_lun = qdepth;
 622         shost->max_lun = iscsi_max_lun;
 623         shost->max_id = 0;
 624         shost->max_channel = 0;
 625         shost->max_cmd_len = 16;
 626 
 627         /*
 628          * older userspace tools (before 2.0-870) did not pass us
 629          * the leading conn's ep so this will be NULL;
 630          */
 631         if (ep) {
 632                 iser_conn = ep->dd_data;
 633                 shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
 634                 shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds);
 635 
 636                 mutex_lock(&iser_conn->state_mutex);
 637                 if (iser_conn->state != ISER_CONN_UP) {
 638                         iser_err("iser conn %p already started teardown\n",
 639                                  iser_conn);
 640                         mutex_unlock(&iser_conn->state_mutex);
 641                         goto free_host;
 642                 }
 643 
 644                 ib_conn = &iser_conn->ib_conn;
 645                 ib_dev = ib_conn->device->ib_device;
 646                 if (ib_conn->pi_support) {
 647                         u32 sig_caps = ib_dev->attrs.sig_prot_cap;
 648 
 649                         shost->sg_prot_tablesize = shost->sg_tablesize;
 650                         scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
 651                         scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
 652                                                    SHOST_DIX_GUARD_CRC);
 653                 }
 654 
 655                 if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG))
 656                         shost->virt_boundary_mask = ~MASK_4K;
 657 
 658                 if (iscsi_host_add(shost, ib_dev->dev.parent)) {
 659                         mutex_unlock(&iser_conn->state_mutex);
 660                         goto free_host;
 661                 }
 662                 mutex_unlock(&iser_conn->state_mutex);
 663         } else {
 664                 shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX);
 665                 if (iscsi_host_add(shost, NULL))
 666                         goto free_host;
 667         }
 668 
 669         max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9;
 670         shost->max_sectors = min(iser_max_sectors, max_fr_sectors);
 671 
 672         iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n",
 673                  iser_conn, shost->sg_tablesize,
 674                  shost->max_sectors);
 675 
 676         if (shost->max_sectors < iser_max_sectors)
 677                 iser_warn("max_sectors was reduced from %u to %u\n",
 678                           iser_max_sectors, shost->max_sectors);
 679 
 680         cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
 681                                           shost->can_queue, 0,
 682                                           sizeof(struct iscsi_iser_task),
 683                                           initial_cmdsn, 0);
 684         if (!cls_session)
 685                 goto remove_host;
 686 
 687         return cls_session;
 688 
 689 remove_host:
 690         iscsi_host_remove(shost);
 691 free_host:
 692         iscsi_host_free(shost);
 693         return NULL;
 694 }
 695 
 696 static int
 697 iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
 698                      enum iscsi_param param, char *buf, int buflen)
 699 {
 700         int value;
 701 
 702         switch (param) {
 703         case ISCSI_PARAM_MAX_RECV_DLENGTH:
 704                 /* TBD */
 705                 break;
 706         case ISCSI_PARAM_HDRDGST_EN:
 707                 sscanf(buf, "%d", &value);
 708                 if (value) {
 709                         iser_err("DataDigest wasn't negotiated to None\n");
 710                         return -EPROTO;
 711                 }
 712                 break;
 713         case ISCSI_PARAM_DATADGST_EN:
 714                 sscanf(buf, "%d", &value);
 715                 if (value) {
 716                         iser_err("DataDigest wasn't negotiated to None\n");
 717                         return -EPROTO;
 718                 }
 719                 break;
 720         case ISCSI_PARAM_IFMARKER_EN:
 721                 sscanf(buf, "%d", &value);
 722                 if (value) {
 723                         iser_err("IFMarker wasn't negotiated to No\n");
 724                         return -EPROTO;
 725                 }
 726                 break;
 727         case ISCSI_PARAM_OFMARKER_EN:
 728                 sscanf(buf, "%d", &value);
 729                 if (value) {
 730                         iser_err("OFMarker wasn't negotiated to No\n");
 731                         return -EPROTO;
 732                 }
 733                 break;
 734         default:
 735                 return iscsi_set_param(cls_conn, param, buf, buflen);
 736         }
 737 
 738         return 0;
 739 }
 740 
 741 /**
 742  * iscsi_iser_set_param() - set class connection parameter
 743  * @cls_conn:    iscsi class connection
 744  * @stats:       iscsi stats to output
 745  *
 746  * Output connection statistics.
 747  */
 748 static void
 749 iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
 750 {
 751         struct iscsi_conn *conn = cls_conn->dd_data;
 752 
 753         stats->txdata_octets = conn->txdata_octets;
 754         stats->rxdata_octets = conn->rxdata_octets;
 755         stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
 756         stats->dataout_pdus = conn->dataout_pdus_cnt;
 757         stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
 758         stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
 759         stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
 760         stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
 761         stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
 762         stats->custom_length = 0;
 763 }
 764 
 765 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
 766                                    enum iscsi_param param, char *buf)
 767 {
 768         struct iser_conn *iser_conn = ep->dd_data;
 769 
 770         switch (param) {
 771         case ISCSI_PARAM_CONN_PORT:
 772         case ISCSI_PARAM_CONN_ADDRESS:
 773                 if (!iser_conn || !iser_conn->ib_conn.cma_id)
 774                         return -ENOTCONN;
 775 
 776                 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
 777                                 &iser_conn->ib_conn.cma_id->route.addr.dst_addr,
 778                                 param, buf);
 779         default:
 780                 break;
 781         }
 782         return -ENOSYS;
 783 }
 784 
 785 /**
 786  * iscsi_iser_ep_connect() - Initiate iSER connection establishment
 787  * @shost:          scsi_host
 788  * @dst_addr:       destination address
 789  * @non-blocking:   indicate if routine can block
 790  *
 791  * Allocate an iscsi endpoint, an iser_conn structure and bind them.
 792  * After that start RDMA connection establishment via rdma_cm. We
 793  * don't allocate iser_conn embedded in iscsi_endpoint since in teardown
 794  * the endpoint will be destroyed at ep_disconnect while iser_conn will
 795  * cleanup its resources asynchronuously.
 796  *
 797  * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error)
 798  *         if fails.
 799  */
 800 static struct iscsi_endpoint *
 801 iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr,
 802                       int non_blocking)
 803 {
 804         int err;
 805         struct iser_conn *iser_conn;
 806         struct iscsi_endpoint *ep;
 807 
 808         ep = iscsi_create_endpoint(0);
 809         if (!ep)
 810                 return ERR_PTR(-ENOMEM);
 811 
 812         iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
 813         if (!iser_conn) {
 814                 err = -ENOMEM;
 815                 goto failure;
 816         }
 817 
 818         ep->dd_data = iser_conn;
 819         iser_conn->ep = ep;
 820         iser_conn_init(iser_conn);
 821 
 822         err = iser_connect(iser_conn, NULL, dst_addr, non_blocking);
 823         if (err)
 824                 goto failure;
 825 
 826         return ep;
 827 failure:
 828         iscsi_destroy_endpoint(ep);
 829         return ERR_PTR(err);
 830 }
 831 
 832 /**
 833  * iscsi_iser_ep_poll() - poll for iser connection establishment to complete
 834  * @ep:            iscsi endpoint (created at ep_connect)
 835  * @timeout_ms:    polling timeout allowed in ms.
 836  *
 837  * This routine boils down to waiting for up_completion signaling
 838  * that cma_id got CONNECTED event.
 839  *
 840  * Return: 1 if succeeded in connection establishment, 0 if timeout expired
 841  *         (libiscsi will retry will kick in) or -1 if interrupted by signal
 842  *         or more likely iser connection state transitioned to TEMINATING or
 843  *         DOWN during the wait period.
 844  */
 845 static int
 846 iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
 847 {
 848         struct iser_conn *iser_conn = ep->dd_data;
 849         int rc;
 850 
 851         rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion,
 852                                                        msecs_to_jiffies(timeout_ms));
 853         /* if conn establishment failed, return error code to iscsi */
 854         if (rc == 0) {
 855                 mutex_lock(&iser_conn->state_mutex);
 856                 if (iser_conn->state == ISER_CONN_TERMINATING ||
 857                     iser_conn->state == ISER_CONN_DOWN)
 858                         rc = -1;
 859                 mutex_unlock(&iser_conn->state_mutex);
 860         }
 861 
 862         iser_info("iser conn %p rc = %d\n", iser_conn, rc);
 863 
 864         if (rc > 0)
 865                 return 1; /* success, this is the equivalent of EPOLLOUT */
 866         else if (!rc)
 867                 return 0; /* timeout */
 868         else
 869                 return rc; /* signal */
 870 }
 871 
 872 /**
 873  * iscsi_iser_ep_disconnect() - Initiate connection teardown process
 874  * @ep:    iscsi endpoint handle
 875  *
 876  * This routine is not blocked by iser and RDMA termination process
 877  * completion as we queue a deffered work for iser/RDMA destruction
 878  * and cleanup or actually call it immediately in case we didn't pass
 879  * iscsi conn bind/start stage, thus it is safe.
 880  */
 881 static void
 882 iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
 883 {
 884         struct iser_conn *iser_conn = ep->dd_data;
 885 
 886         iser_info("ep %p iser conn %p\n", ep, iser_conn);
 887 
 888         mutex_lock(&iser_conn->state_mutex);
 889         iser_conn_terminate(iser_conn);
 890 
 891         /*
 892          * if iser_conn and iscsi_conn are bound, we must wait for
 893          * iscsi_conn_stop and flush errors completion before freeing
 894          * the iser resources. Otherwise we are safe to free resources
 895          * immediately.
 896          */
 897         if (iser_conn->iscsi_conn) {
 898                 INIT_WORK(&iser_conn->release_work, iser_release_work);
 899                 queue_work(release_wq, &iser_conn->release_work);
 900                 mutex_unlock(&iser_conn->state_mutex);
 901         } else {
 902                 iser_conn->state = ISER_CONN_DOWN;
 903                 mutex_unlock(&iser_conn->state_mutex);
 904                 iser_conn_release(iser_conn);
 905         }
 906 
 907         iscsi_destroy_endpoint(ep);
 908 }
 909 
 910 static umode_t iser_attr_is_visible(int param_type, int param)
 911 {
 912         switch (param_type) {
 913         case ISCSI_HOST_PARAM:
 914                 switch (param) {
 915                 case ISCSI_HOST_PARAM_NETDEV_NAME:
 916                 case ISCSI_HOST_PARAM_HWADDRESS:
 917                 case ISCSI_HOST_PARAM_INITIATOR_NAME:
 918                         return S_IRUGO;
 919                 default:
 920                         return 0;
 921                 }
 922         case ISCSI_PARAM:
 923                 switch (param) {
 924                 case ISCSI_PARAM_MAX_RECV_DLENGTH:
 925                 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
 926                 case ISCSI_PARAM_HDRDGST_EN:
 927                 case ISCSI_PARAM_DATADGST_EN:
 928                 case ISCSI_PARAM_CONN_ADDRESS:
 929                 case ISCSI_PARAM_CONN_PORT:
 930                 case ISCSI_PARAM_EXP_STATSN:
 931                 case ISCSI_PARAM_PERSISTENT_ADDRESS:
 932                 case ISCSI_PARAM_PERSISTENT_PORT:
 933                 case ISCSI_PARAM_PING_TMO:
 934                 case ISCSI_PARAM_RECV_TMO:
 935                 case ISCSI_PARAM_INITIAL_R2T_EN:
 936                 case ISCSI_PARAM_MAX_R2T:
 937                 case ISCSI_PARAM_IMM_DATA_EN:
 938                 case ISCSI_PARAM_FIRST_BURST:
 939                 case ISCSI_PARAM_MAX_BURST:
 940                 case ISCSI_PARAM_PDU_INORDER_EN:
 941                 case ISCSI_PARAM_DATASEQ_INORDER_EN:
 942                 case ISCSI_PARAM_TARGET_NAME:
 943                 case ISCSI_PARAM_TPGT:
 944                 case ISCSI_PARAM_USERNAME:
 945                 case ISCSI_PARAM_PASSWORD:
 946                 case ISCSI_PARAM_USERNAME_IN:
 947                 case ISCSI_PARAM_PASSWORD_IN:
 948                 case ISCSI_PARAM_FAST_ABORT:
 949                 case ISCSI_PARAM_ABORT_TMO:
 950                 case ISCSI_PARAM_LU_RESET_TMO:
 951                 case ISCSI_PARAM_TGT_RESET_TMO:
 952                 case ISCSI_PARAM_IFACE_NAME:
 953                 case ISCSI_PARAM_INITIATOR_NAME:
 954                 case ISCSI_PARAM_DISCOVERY_SESS:
 955                         return S_IRUGO;
 956                 default:
 957                         return 0;
 958                 }
 959         }
 960 
 961         return 0;
 962 }
 963 
 964 static struct scsi_host_template iscsi_iser_sht = {
 965         .module                 = THIS_MODULE,
 966         .name                   = "iSCSI Initiator over iSER",
 967         .queuecommand           = iscsi_queuecommand,
 968         .change_queue_depth     = scsi_change_queue_depth,
 969         .sg_tablesize           = ISCSI_ISER_DEF_SG_TABLESIZE,
 970         .cmd_per_lun            = ISER_DEF_CMD_PER_LUN,
 971         .eh_timed_out           = iscsi_eh_cmd_timed_out,
 972         .eh_abort_handler       = iscsi_eh_abort,
 973         .eh_device_reset_handler= iscsi_eh_device_reset,
 974         .eh_target_reset_handler = iscsi_eh_recover_target,
 975         .target_alloc           = iscsi_target_alloc,
 976         .proc_name              = "iscsi_iser",
 977         .this_id                = -1,
 978         .track_queue_depth      = 1,
 979 };
 980 
 981 static struct iscsi_transport iscsi_iser_transport = {
 982         .owner                  = THIS_MODULE,
 983         .name                   = "iser",
 984         .caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO,
 985         /* session management */
 986         .create_session         = iscsi_iser_session_create,
 987         .destroy_session        = iscsi_iser_session_destroy,
 988         /* connection management */
 989         .create_conn            = iscsi_iser_conn_create,
 990         .bind_conn              = iscsi_iser_conn_bind,
 991         .destroy_conn           = iscsi_conn_teardown,
 992         .attr_is_visible        = iser_attr_is_visible,
 993         .set_param              = iscsi_iser_set_param,
 994         .get_conn_param         = iscsi_conn_get_param,
 995         .get_ep_param           = iscsi_iser_get_ep_param,
 996         .get_session_param      = iscsi_session_get_param,
 997         .start_conn             = iscsi_iser_conn_start,
 998         .stop_conn              = iscsi_iser_conn_stop,
 999         /* iscsi host params */
1000         .get_host_param         = iscsi_host_get_param,
1001         .set_host_param         = iscsi_host_set_param,
1002         /* IO */
1003         .send_pdu               = iscsi_conn_send_pdu,
1004         .get_stats              = iscsi_iser_conn_get_stats,
1005         .init_task              = iscsi_iser_task_init,
1006         .xmit_task              = iscsi_iser_task_xmit,
1007         .cleanup_task           = iscsi_iser_cleanup_task,
1008         .alloc_pdu              = iscsi_iser_pdu_alloc,
1009         .check_protection       = iscsi_iser_check_protection,
1010         /* recovery */
1011         .session_recovery_timedout = iscsi_session_recovery_timedout,
1012 
1013         .ep_connect             = iscsi_iser_ep_connect,
1014         .ep_poll                = iscsi_iser_ep_poll,
1015         .ep_disconnect          = iscsi_iser_ep_disconnect
1016 };
1017 
1018 static int __init iser_init(void)
1019 {
1020         int err;
1021 
1022         iser_dbg("Starting iSER datamover...\n");
1023 
1024         if (iscsi_max_lun < 1) {
1025                 iser_err("Invalid max_lun value of %u\n", iscsi_max_lun);
1026                 return -EINVAL;
1027         }
1028 
1029         memset(&ig, 0, sizeof(struct iser_global));
1030 
1031         ig.desc_cache = kmem_cache_create("iser_descriptors",
1032                                           sizeof(struct iser_tx_desc),
1033                                           0, SLAB_HWCACHE_ALIGN,
1034                                           NULL);
1035         if (ig.desc_cache == NULL)
1036                 return -ENOMEM;
1037 
1038         /* device init is called only after the first addr resolution */
1039         mutex_init(&ig.device_list_mutex);
1040         INIT_LIST_HEAD(&ig.device_list);
1041         mutex_init(&ig.connlist_mutex);
1042         INIT_LIST_HEAD(&ig.connlist);
1043 
1044         release_wq = alloc_workqueue("release workqueue", 0, 0);
1045         if (!release_wq) {
1046                 iser_err("failed to allocate release workqueue\n");
1047                 err = -ENOMEM;
1048                 goto err_alloc_wq;
1049         }
1050 
1051         iscsi_iser_scsi_transport = iscsi_register_transport(
1052                                                         &iscsi_iser_transport);
1053         if (!iscsi_iser_scsi_transport) {
1054                 iser_err("iscsi_register_transport failed\n");
1055                 err = -EINVAL;
1056                 goto err_reg;
1057         }
1058 
1059         return 0;
1060 
1061 err_reg:
1062         destroy_workqueue(release_wq);
1063 err_alloc_wq:
1064         kmem_cache_destroy(ig.desc_cache);
1065 
1066         return err;
1067 }
1068 
1069 static void __exit iser_exit(void)
1070 {
1071         struct iser_conn *iser_conn, *n;
1072         int connlist_empty;
1073 
1074         iser_dbg("Removing iSER datamover...\n");
1075         destroy_workqueue(release_wq);
1076 
1077         mutex_lock(&ig.connlist_mutex);
1078         connlist_empty = list_empty(&ig.connlist);
1079         mutex_unlock(&ig.connlist_mutex);
1080 
1081         if (!connlist_empty) {
1082                 iser_err("Error cleanup stage completed but we still have iser "
1083                          "connections, destroying them anyway\n");
1084                 list_for_each_entry_safe(iser_conn, n, &ig.connlist,
1085                                          conn_list) {
1086                         iser_conn_release(iser_conn);
1087                 }
1088         }
1089 
1090         iscsi_unregister_transport(&iscsi_iser_transport);
1091         kmem_cache_destroy(ig.desc_cache);
1092 }
1093 
1094 module_init(iser_init);
1095 module_exit(iser_exit);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/infiniband/ulp/iser/iscsi_iser.c

DEFINITIONS
