Pileus Git - ~andy/linux/blob - drivers/infiniband/ulp/iser/iser_verbs.c

   1 /*
   2  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
   3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
   4  * Copyright (c) 2013 Mellanox Technologies. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  */
  34 #include <linux/kernel.h>
  35 #include <linux/module.h>
  36 #include <linux/slab.h>
  37 #include <linux/delay.h>
  38
  39 #include "iscsi_iser.h"
  40
  41 #define ISCSI_ISER_MAX_CONN     8
  42 #define ISER_MAX_RX_CQ_LEN      (ISER_QP_MAX_RECV_DTOS * ISCSI_ISER_MAX_CONN)
  43 #define ISER_MAX_TX_CQ_LEN      (ISER_QP_MAX_REQ_DTOS  * ISCSI_ISER_MAX_CONN)
  44
  45 static void iser_cq_tasklet_fn(unsigned long data);
  46 static void iser_cq_callback(struct ib_cq *cq, void *cq_context);
  47
  48 static void iser_cq_event_callback(struct ib_event *cause, void *context)
  49 {
  50         iser_err("got cq event %d \n", cause->event);
  51 }
  52
  53 static void iser_qp_event_callback(struct ib_event *cause, void *context)
  54 {
  55         iser_err("got qp event %d\n",cause->event);
  56 }
  57
  58 static void iser_event_handler(struct ib_event_handler *handler,
  59                                 struct ib_event *event)
  60 {
  61         iser_err("async event %d on device %s port %d\n", event->event,
  62                 event->device->name, event->element.port_num);
  63 }
  64
  65 /**
  66  * iser_create_device_ib_res - creates Protection Domain (PD), Completion
  67  * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with
  68  * the adapator.
  69  *
  70  * returns 0 on success, -1 on failure
  71  */
  72 static int iser_create_device_ib_res(struct iser_device *device)
  73 {
  74         int i, j;
  75         struct iser_cq_desc *cq_desc;
  76
  77         device->cqs_used = min(ISER_MAX_CQ, device->ib_device->num_comp_vectors);
  78         iser_info("using %d CQs, device %s supports %d vectors\n",
  79                   device->cqs_used, device->ib_device->name,
  80                   device->ib_device->num_comp_vectors);
  81
  82         device->cq_desc = kmalloc(sizeof(struct iser_cq_desc) * device->cqs_used,
  83                                   GFP_KERNEL);
  84         if (device->cq_desc == NULL)
  85                 goto cq_desc_err;
  86         cq_desc = device->cq_desc;
  87
  88         device->pd = ib_alloc_pd(device->ib_device);
  89         if (IS_ERR(device->pd))
  90                 goto pd_err;
  91
  92         for (i = 0; i < device->cqs_used; i++) {
  93                 cq_desc[i].device   = device;
  94                 cq_desc[i].cq_index = i;
  95
  96                 device->rx_cq[i] = ib_create_cq(device->ib_device,
  97                                           iser_cq_callback,
  98                                           iser_cq_event_callback,
  99                                           (void *)&cq_desc[i],
 100                                           ISER_MAX_RX_CQ_LEN, i);
 101                 if (IS_ERR(device->rx_cq[i]))
 102                         goto cq_err;
 103
 104                 device->tx_cq[i] = ib_create_cq(device->ib_device,
 105                                           NULL, iser_cq_event_callback,
 106                                           (void *)&cq_desc[i],
 107                                           ISER_MAX_TX_CQ_LEN, i);
 108
 109                 if (IS_ERR(device->tx_cq[i]))
 110                         goto cq_err;
 111
 112                 if (ib_req_notify_cq(device->rx_cq[i], IB_CQ_NEXT_COMP))
 113                         goto cq_err;
 114
 115                 tasklet_init(&device->cq_tasklet[i],
 116                              iser_cq_tasklet_fn,
 117                         (unsigned long)&cq_desc[i]);
 118         }
 119
 120         device->mr = ib_get_dma_mr(device->pd, IB_ACCESS_LOCAL_WRITE |
 121                                    IB_ACCESS_REMOTE_WRITE |
 122                                    IB_ACCESS_REMOTE_READ);
 123         if (IS_ERR(device->mr))
 124                 goto dma_mr_err;
 125
 126         INIT_IB_EVENT_HANDLER(&device->event_handler, device->ib_device,
 127                                 iser_event_handler);
 128         if (ib_register_event_handler(&device->event_handler))
 129                 goto handler_err;
 130
 131         return 0;
 132
 133 handler_err:
 134         ib_dereg_mr(device->mr);
 135 dma_mr_err:
 136         for (j = 0; j < device->cqs_used; j++)
 137                 tasklet_kill(&device->cq_tasklet[j]);
 138 cq_err:
 139         for (j = 0; j < i; j++) {
 140                 if (device->tx_cq[j])
 141                         ib_destroy_cq(device->tx_cq[j]);
 142                 if (device->rx_cq[j])
 143                         ib_destroy_cq(device->rx_cq[j]);
 144         }
 145         ib_dealloc_pd(device->pd);
 146 pd_err:
 147         kfree(device->cq_desc);
 148 cq_desc_err:
 149         iser_err("failed to allocate an IB resource\n");
 150         return -1;
 151 }
 152
 153 /**
 154  * iser_free_device_ib_res - destroy/dealloc/dereg the DMA MR,
 155  * CQ and PD created with the device associated with the adapator.
 156  */
 157 static void iser_free_device_ib_res(struct iser_device *device)
 158 {
 159         int i;
 160         BUG_ON(device->mr == NULL);
 161
 162         for (i = 0; i < device->cqs_used; i++) {
 163                 tasklet_kill(&device->cq_tasklet[i]);
 164                 (void)ib_destroy_cq(device->tx_cq[i]);
 165                 (void)ib_destroy_cq(device->rx_cq[i]);
 166                 device->tx_cq[i] = NULL;
 167                 device->rx_cq[i] = NULL;
 168         }
 169
 170         (void)ib_unregister_event_handler(&device->event_handler);
 171         (void)ib_dereg_mr(device->mr);
 172         (void)ib_dealloc_pd(device->pd);
 173
 174         kfree(device->cq_desc);
 175
 176         device->mr = NULL;
 177         device->pd = NULL;
 178 }
 179
 180 /**
 181  * iser_create_ib_conn_res - Creates FMR pool and Queue-Pair (QP)
 182  *
 183  * returns 0 on success, -1 on failure
 184  */
 185 static int iser_create_ib_conn_res(struct iser_conn *ib_conn)
 186 {
 187         struct iser_device      *device;
 188         struct ib_qp_init_attr  init_attr;
 189         int                     req_err, resp_err, ret = -ENOMEM;
 190         struct ib_fmr_pool_param params;
 191         int index, min_index = 0;
 192
 193         BUG_ON(ib_conn->device == NULL);
 194
 195         device = ib_conn->device;
 196
 197         ib_conn->login_buf = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN +
 198                                         ISER_RX_LOGIN_SIZE, GFP_KERNEL);
 199         if (!ib_conn->login_buf)
 200                 goto out_err;
 201
 202         ib_conn->login_req_buf  = ib_conn->login_buf;
 203         ib_conn->login_resp_buf = ib_conn->login_buf + ISCSI_DEF_MAX_RECV_SEG_LEN;
 204
 205         ib_conn->login_req_dma = ib_dma_map_single(ib_conn->device->ib_device,
 206                                 (void *)ib_conn->login_req_buf,
 207                                 ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);
 208
 209         ib_conn->login_resp_dma = ib_dma_map_single(ib_conn->device->ib_device,
 210                                 (void *)ib_conn->login_resp_buf,
 211                                 ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);
 212
 213         req_err  = ib_dma_mapping_error(device->ib_device, ib_conn->login_req_dma);
 214         resp_err = ib_dma_mapping_error(device->ib_device, ib_conn->login_resp_dma);
 215
 216         if (req_err || resp_err) {
 217                 if (req_err)
 218                         ib_conn->login_req_dma = 0;
 219                 if (resp_err)
 220                         ib_conn->login_resp_dma = 0;
 221                 goto out_err;
 222         }
 223
 224         ib_conn->page_vec = kmalloc(sizeof(struct iser_page_vec) +
 225                                     (sizeof(u64) * (ISCSI_ISER_SG_TABLESIZE +1)),
 226                                     GFP_KERNEL);
 227         if (!ib_conn->page_vec)
 228                 goto out_err;
 229
 230         ib_conn->page_vec->pages = (u64 *) (ib_conn->page_vec + 1);
 231
 232         params.page_shift        = SHIFT_4K;
 233         /* when the first/last SG element are not start/end *
 234          * page aligned, the map whould be of N+1 pages     */
 235         params.max_pages_per_fmr = ISCSI_ISER_SG_TABLESIZE + 1;
 236         /* make the pool size twice the max number of SCSI commands *
 237          * the ML is expected to queue, watermark for unmap at 50%  */
 238         params.pool_size         = ISCSI_DEF_XMIT_CMDS_MAX * 2;
 239         params.dirty_watermark   = ISCSI_DEF_XMIT_CMDS_MAX;
 240         params.cache             = 0;
 241         params.flush_function    = NULL;
 242         params.access            = (IB_ACCESS_LOCAL_WRITE  |
 243                                     IB_ACCESS_REMOTE_WRITE |
 244                                     IB_ACCESS_REMOTE_READ);
 245
 246         ib_conn->fmr_pool = ib_create_fmr_pool(device->pd, &params);
 247         ret = PTR_ERR(ib_conn->fmr_pool);
 248         if (IS_ERR(ib_conn->fmr_pool) && ret != -ENOSYS) {
 249                 ib_conn->fmr_pool = NULL;
 250                 goto out_err;
 251         } else if (ret == -ENOSYS) {
 252                 ib_conn->fmr_pool = NULL;
 253                 iser_warn("FMRs are not supported, using unaligned mode\n");
 254                 ret = 0;
 255         }
 256
 257         memset(&init_attr, 0, sizeof init_attr);
 258
 259         mutex_lock(&ig.connlist_mutex);
 260         /* select the CQ with the minimal number of usages */
 261         for (index = 0; index < device->cqs_used; index++)
 262                 if (device->cq_active_qps[index] <
 263                     device->cq_active_qps[min_index])
 264                         min_index = index;
 265         device->cq_active_qps[min_index]++;
 266         mutex_unlock(&ig.connlist_mutex);
 267         iser_info("cq index %d used for ib_conn %p\n", min_index, ib_conn);
 268
 269         init_attr.event_handler = iser_qp_event_callback;
 270         init_attr.qp_context    = (void *)ib_conn;
 271         init_attr.send_cq       = device->tx_cq[min_index];
 272         init_attr.recv_cq       = device->rx_cq[min_index];
 273         init_attr.cap.max_send_wr  = ISER_QP_MAX_REQ_DTOS;
 274         init_attr.cap.max_recv_wr  = ISER_QP_MAX_RECV_DTOS;
 275         init_attr.cap.max_send_sge = 2;
 276         init_attr.cap.max_recv_sge = 1;
 277         init_attr.sq_sig_type   = IB_SIGNAL_REQ_WR;
 278         init_attr.qp_type       = IB_QPT_RC;
 279
 280         ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr);
 281         if (ret)
 282                 goto out_err;
 283
 284         ib_conn->qp = ib_conn->cma_id->qp;
 285         iser_info("setting conn %p cma_id %p: fmr_pool %p qp %p\n",
 286                   ib_conn, ib_conn->cma_id,
 287                   ib_conn->fmr_pool, ib_conn->cma_id->qp);
 288         return ret;
 289
 290 out_err:
 291         iser_err("unable to alloc mem or create resource, err %d\n", ret);
 292         return ret;
 293 }
 294
 295 /**
 296  * releases the FMR pool and QP objects, returns 0 on success,
 297  * -1 on failure
 298  */
 299 static int iser_free_ib_conn_res(struct iser_conn *ib_conn)
 300 {
 301         int cq_index;
 302         BUG_ON(ib_conn == NULL);
 303
 304         iser_info("freeing conn %p cma_id %p fmr pool %p qp %p\n",
 305                   ib_conn, ib_conn->cma_id,
 306                   ib_conn->fmr_pool, ib_conn->qp);
 307
 308         /* qp is created only once both addr & route are resolved */
 309         if (ib_conn->fmr_pool != NULL)
 310                 ib_destroy_fmr_pool(ib_conn->fmr_pool);
 311
 312         if (ib_conn->qp != NULL) {
 313                 cq_index = ((struct iser_cq_desc *)ib_conn->qp->recv_cq->cq_context)->cq_index;
 314                 ib_conn->device->cq_active_qps[cq_index]--;
 315
 316                 rdma_destroy_qp(ib_conn->cma_id);
 317         }
 318
 319         ib_conn->fmr_pool = NULL;
 320         ib_conn->qp       = NULL;
 321         kfree(ib_conn->page_vec);
 322
 323         if (ib_conn->login_buf) {
 324                 if (ib_conn->login_req_dma)
 325                         ib_dma_unmap_single(ib_conn->device->ib_device,
 326                                 ib_conn->login_req_dma,
 327                                 ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);
 328                 if (ib_conn->login_resp_dma)
 329                         ib_dma_unmap_single(ib_conn->device->ib_device,
 330                                 ib_conn->login_resp_dma,
 331                                 ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);
 332                 kfree(ib_conn->login_buf);
 333         }
 334
 335         return 0;
 336 }
 337
 338 /**
 339  * based on the resolved device node GUID see if there already allocated
 340  * device for this device. If there's no such, create one.
 341  */
 342 static
 343 struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id)
 344 {
 345         struct iser_device *device;
 346
 347         mutex_lock(&ig.device_list_mutex);
 348
 349         list_for_each_entry(device, &ig.device_list, ig_list)
 350                 /* find if there's a match using the node GUID */
 351                 if (device->ib_device->node_guid == cma_id->device->node_guid)
 352                         goto inc_refcnt;
 353
 354         device = kzalloc(sizeof *device, GFP_KERNEL);
 355         if (device == NULL)
 356                 goto out;
 357
 358         /* assign this device to the device */
 359         device->ib_device = cma_id->device;
 360         /* init the device and link it into ig device list */
 361         if (iser_create_device_ib_res(device)) {
 362                 kfree(device);
 363                 device = NULL;
 364                 goto out;
 365         }
 366         list_add(&device->ig_list, &ig.device_list);
 367
 368 inc_refcnt:
 369         device->refcount++;
 370 out:
 371         mutex_unlock(&ig.device_list_mutex);
 372         return device;
 373 }
 374
 375 /* if there's no demand for this device, release it */
 376 static void iser_device_try_release(struct iser_device *device)
 377 {
 378         mutex_lock(&ig.device_list_mutex);
 379         device->refcount--;
 380         iser_info("device %p refcount %d\n", device, device->refcount);
 381         if (!device->refcount) {
 382                 iser_free_device_ib_res(device);
 383                 list_del(&device->ig_list);
 384                 kfree(device);
 385         }
 386         mutex_unlock(&ig.device_list_mutex);
 387 }
 388
 389 static int iser_conn_state_comp_exch(struct iser_conn *ib_conn,
 390                                      enum iser_ib_conn_state comp,
 391                                      enum iser_ib_conn_state exch)
 392 {
 393         int ret;
 394
 395         spin_lock_bh(&ib_conn->lock);
 396         if ((ret = (ib_conn->state == comp)))
 397                 ib_conn->state = exch;
 398         spin_unlock_bh(&ib_conn->lock);
 399         return ret;
 400 }
 401
 402 /**
 403  * Frees all conn objects and deallocs conn descriptor
 404  */
 405 static void iser_conn_release(struct iser_conn *ib_conn, int can_destroy_id)
 406 {
 407         struct iser_device  *device = ib_conn->device;
 408
 409         BUG_ON(ib_conn->state != ISER_CONN_DOWN);
 410
 411         mutex_lock(&ig.connlist_mutex);
 412         list_del(&ib_conn->conn_list);
 413         mutex_unlock(&ig.connlist_mutex);
 414         iser_free_rx_descriptors(ib_conn);
 415         iser_free_ib_conn_res(ib_conn);
 416         ib_conn->device = NULL;
 417         /* on EVENT_ADDR_ERROR there's no device yet for this conn */
 418         if (device != NULL)
 419                 iser_device_try_release(device);
 420         /* if cma handler context, the caller actually destroy the id */
 421         if (ib_conn->cma_id != NULL && can_destroy_id) {
 422                 rdma_destroy_id(ib_conn->cma_id);
 423                 ib_conn->cma_id = NULL;
 424         }
 425         iscsi_destroy_endpoint(ib_conn->ep);
 426 }
 427
 428 void iser_conn_get(struct iser_conn *ib_conn)
 429 {
 430         atomic_inc(&ib_conn->refcount);
 431 }
 432
 433 int iser_conn_put(struct iser_conn *ib_conn, int can_destroy_id)
 434 {
 435         if (atomic_dec_and_test(&ib_conn->refcount)) {
 436                 iser_conn_release(ib_conn, can_destroy_id);
 437                 return 1;
 438         }
 439         return 0;
 440 }
 441
 442 /**
 443  * triggers start of the disconnect procedures and wait for them to be done
 444  */
 445 void iser_conn_terminate(struct iser_conn *ib_conn)
 446 {
 447         int err = 0;
 448
 449         /* change the ib conn state only if the conn is UP, however always call
 450          * rdma_disconnect since this is the only way to cause the CMA to change
 451          * the QP state to ERROR
 452          */
 453
 454         iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, ISER_CONN_TERMINATING);
 455         err = rdma_disconnect(ib_conn->cma_id);
 456         if (err)
 457                 iser_err("Failed to disconnect, conn: 0x%p err %d\n",
 458                          ib_conn,err);
 459
 460         wait_event_interruptible(ib_conn->wait,
 461                                  ib_conn->state == ISER_CONN_DOWN);
 462
 463         iser_conn_put(ib_conn, 1); /* deref ib conn deallocate */
 464 }
 465
 466 static int iser_connect_error(struct rdma_cm_id *cma_id)
 467 {
 468         struct iser_conn *ib_conn;
 469         ib_conn = (struct iser_conn *)cma_id->context;
 470
 471         ib_conn->state = ISER_CONN_DOWN;
 472         wake_up_interruptible(&ib_conn->wait);
 473         return iser_conn_put(ib_conn, 0); /* deref ib conn's cma id */
 474 }
 475
 476 static int iser_addr_handler(struct rdma_cm_id *cma_id)
 477 {
 478         struct iser_device *device;
 479         struct iser_conn   *ib_conn;
 480         int    ret;
 481
 482         device = iser_device_find_by_ib_device(cma_id);
 483         if (!device) {
 484                 iser_err("device lookup/creation failed\n");
 485                 return iser_connect_error(cma_id);
 486         }
 487
 488         ib_conn = (struct iser_conn *)cma_id->context;
 489         ib_conn->device = device;
 490
 491         ret = rdma_resolve_route(cma_id, 1000);
 492         if (ret) {
 493                 iser_err("resolve route failed: %d\n", ret);
 494                 return iser_connect_error(cma_id);
 495         }
 496
 497         return 0;
 498 }
 499
 500 static int iser_route_handler(struct rdma_cm_id *cma_id)
 501 {
 502         struct rdma_conn_param conn_param;
 503         int    ret;
 504         struct iser_cm_hdr req_hdr;
 505
 506         ret = iser_create_ib_conn_res((struct iser_conn *)cma_id->context);
 507         if (ret)
 508                 goto failure;
 509
 510         memset(&conn_param, 0, sizeof conn_param);
 511         conn_param.responder_resources = 4;
 512         conn_param.initiator_depth     = 1;
 513         conn_param.retry_count         = 7;
 514         conn_param.rnr_retry_count     = 6;
 515
 516         memset(&req_hdr, 0, sizeof(req_hdr));
 517         req_hdr.flags = (ISER_ZBVA_NOT_SUPPORTED |
 518                         ISER_SEND_W_INV_NOT_SUPPORTED);
 519         conn_param.private_data         = (void *)&req_hdr;
 520         conn_param.private_data_len     = sizeof(struct iser_cm_hdr);
 521
 522         ret = rdma_connect(cma_id, &conn_param);
 523         if (ret) {
 524                 iser_err("failure connecting: %d\n", ret);
 525                 goto failure;
 526         }
 527
 528         return 0;
 529 failure:
 530         return iser_connect_error(cma_id);
 531 }
 532
 533 static void iser_connected_handler(struct rdma_cm_id *cma_id)
 534 {
 535         struct iser_conn *ib_conn;
 536
 537         ib_conn = (struct iser_conn *)cma_id->context;
 538         ib_conn->state = ISER_CONN_UP;
 539         wake_up_interruptible(&ib_conn->wait);
 540 }
 541
 542 static int iser_disconnected_handler(struct rdma_cm_id *cma_id)
 543 {
 544         struct iser_conn *ib_conn;
 545         int ret;
 546
 547         ib_conn = (struct iser_conn *)cma_id->context;
 548
 549         /* getting here when the state is UP means that the conn is being *
 550          * terminated asynchronously from the iSCSI layer's perspective.  */
 551         if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
 552                                       ISER_CONN_TERMINATING))
 553                 iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
 554                                    ISCSI_ERR_CONN_FAILED);
 555
 556         /* Complete the termination process if no posts are pending */
 557         if (ib_conn->post_recv_buf_count == 0 &&
 558             (atomic_read(&ib_conn->post_send_buf_count) == 0)) {
 559                 ib_conn->state = ISER_CONN_DOWN;
 560                 wake_up_interruptible(&ib_conn->wait);
 561         }
 562
 563         ret = iser_conn_put(ib_conn, 0); /* deref ib conn's cma id */
 564         return ret;
 565 }
 566
 567 static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
 568 {
 569         int ret = 0;
 570
 571         iser_info("event %d status %d conn %p id %p\n",
 572                   event->event, event->status, cma_id->context, cma_id);
 573
 574         switch (event->event) {
 575         case RDMA_CM_EVENT_ADDR_RESOLVED:
 576                 ret = iser_addr_handler(cma_id);
 577                 break;
 578         case RDMA_CM_EVENT_ROUTE_RESOLVED:
 579                 ret = iser_route_handler(cma_id);
 580                 break;
 581         case RDMA_CM_EVENT_ESTABLISHED:
 582                 iser_connected_handler(cma_id);
 583                 break;
 584         case RDMA_CM_EVENT_ADDR_ERROR:
 585         case RDMA_CM_EVENT_ROUTE_ERROR:
 586         case RDMA_CM_EVENT_CONNECT_ERROR:
 587         case RDMA_CM_EVENT_UNREACHABLE:
 588         case RDMA_CM_EVENT_REJECTED:
 589                 ret = iser_connect_error(cma_id);
 590                 break;
 591         case RDMA_CM_EVENT_DISCONNECTED:
 592         case RDMA_CM_EVENT_DEVICE_REMOVAL:
 593         case RDMA_CM_EVENT_ADDR_CHANGE:
 594                 ret = iser_disconnected_handler(cma_id);
 595                 break;
 596         default:
 597                 iser_err("Unexpected RDMA CM event (%d)\n", event->event);
 598                 break;
 599         }
 600         return ret;
 601 }
 602
 603 void iser_conn_init(struct iser_conn *ib_conn)
 604 {
 605         ib_conn->state = ISER_CONN_INIT;
 606         init_waitqueue_head(&ib_conn->wait);
 607         ib_conn->post_recv_buf_count = 0;
 608         atomic_set(&ib_conn->post_send_buf_count, 0);
 609         atomic_set(&ib_conn->refcount, 1); /* ref ib conn allocation */
 610         INIT_LIST_HEAD(&ib_conn->conn_list);
 611         spin_lock_init(&ib_conn->lock);
 612 }
 613
 614  /**
 615  * starts the process of connecting to the target
 616  * sleeps until the connection is established or rejected
 617  */
 618 int iser_connect(struct iser_conn   *ib_conn,
 619                  struct sockaddr_in *src_addr,
 620                  struct sockaddr_in *dst_addr,
 621                  int                 non_blocking)
 622 {
 623         struct sockaddr *src, *dst;
 624         int err = 0;
 625
 626         sprintf(ib_conn->name, "%pI4:%d",
 627                 &dst_addr->sin_addr.s_addr, dst_addr->sin_port);
 628
 629         /* the device is known only --after-- address resolution */
 630         ib_conn->device = NULL;
 631
 632         iser_info("connecting to: %pI4, port 0x%x\n",
 633                   &dst_addr->sin_addr, dst_addr->sin_port);
 634
 635         ib_conn->state = ISER_CONN_PENDING;
 636
 637         iser_conn_get(ib_conn); /* ref ib conn's cma id */
 638         ib_conn->cma_id = rdma_create_id(iser_cma_handler,
 639                                              (void *)ib_conn,
 640                                              RDMA_PS_TCP, IB_QPT_RC);
 641         if (IS_ERR(ib_conn->cma_id)) {
 642                 err = PTR_ERR(ib_conn->cma_id);
 643                 iser_err("rdma_create_id failed: %d\n", err);
 644                 goto id_failure;
 645         }
 646
 647         src = (struct sockaddr *)src_addr;
 648         dst = (struct sockaddr *)dst_addr;
 649         err = rdma_resolve_addr(ib_conn->cma_id, src, dst, 1000);
 650         if (err) {
 651                 iser_err("rdma_resolve_addr failed: %d\n", err);
 652                 goto addr_failure;
 653         }
 654
 655         if (!non_blocking) {
 656                 wait_event_interruptible(ib_conn->wait,
 657                                          (ib_conn->state != ISER_CONN_PENDING));
 658
 659                 if (ib_conn->state != ISER_CONN_UP) {
 660                         err =  -EIO;
 661                         goto connect_failure;
 662                 }
 663         }
 664
 665         mutex_lock(&ig.connlist_mutex);
 666         list_add(&ib_conn->conn_list, &ig.connlist);
 667         mutex_unlock(&ig.connlist_mutex);
 668         return 0;
 669
 670 id_failure:
 671         ib_conn->cma_id = NULL;
 672 addr_failure:
 673         ib_conn->state = ISER_CONN_DOWN;
 674         iser_conn_put(ib_conn, 1); /* deref ib conn's cma id */
 675 connect_failure:
 676         iser_conn_put(ib_conn, 1); /* deref ib conn deallocate */
 677         return err;
 678 }
 679
 680 /**
 681  * iser_reg_page_vec - Register physical memory
 682  *
 683  * returns: 0 on success, errno code on failure
 684  */
 685 int iser_reg_page_vec(struct iser_conn     *ib_conn,
 686                       struct iser_page_vec *page_vec,
 687                       struct iser_mem_reg  *mem_reg)
 688 {
 689         struct ib_pool_fmr *mem;
 690         u64                io_addr;
 691         u64                *page_list;
 692         int                status;
 693
 694         page_list = page_vec->pages;
 695         io_addr   = page_list[0];
 696
 697         mem  = ib_fmr_pool_map_phys(ib_conn->fmr_pool,
 698                                     page_list,
 699                                     page_vec->length,
 700                                     io_addr);
 701
 702         if (IS_ERR(mem)) {
 703                 status = (int)PTR_ERR(mem);
 704                 iser_err("ib_fmr_pool_map_phys failed: %d\n", status);
 705                 return status;
 706         }
 707
 708         mem_reg->lkey  = mem->fmr->lkey;
 709         mem_reg->rkey  = mem->fmr->rkey;
 710         mem_reg->len   = page_vec->length * SIZE_4K;
 711         mem_reg->va    = io_addr;
 712         mem_reg->is_fmr = 1;
 713         mem_reg->mem_h = (void *)mem;
 714
 715         mem_reg->va   += page_vec->offset;
 716         mem_reg->len   = page_vec->data_size;
 717
 718         iser_dbg("PHYSICAL Mem.register, [PHYS p_array: 0x%p, sz: %d, "
 719                  "entry[0]: (0x%08lx,%ld)] -> "
 720                  "[lkey: 0x%08X mem_h: 0x%p va: 0x%08lX sz: %ld]\n",
 721                  page_vec, page_vec->length,
 722                  (unsigned long)page_vec->pages[0],
 723                  (unsigned long)page_vec->data_size,
 724                  (unsigned int)mem_reg->lkey, mem_reg->mem_h,
 725                  (unsigned long)mem_reg->va, (unsigned long)mem_reg->len);
 726         return 0;
 727 }
 728
 729 /**
 730  * Unregister (previosuly registered) memory.
 731  */
 732 void iser_unreg_mem(struct iser_mem_reg *reg)
 733 {
 734         int ret;
 735
 736         iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n",reg->mem_h);
 737
 738         ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h);
 739         if (ret)
 740                 iser_err("ib_fmr_pool_unmap failed %d\n", ret);
 741
 742         reg->mem_h = NULL;
 743 }
 744
 745 int iser_post_recvl(struct iser_conn *ib_conn)
 746 {
 747         struct ib_recv_wr rx_wr, *rx_wr_failed;
 748         struct ib_sge     sge;
 749         int ib_ret;
 750
 751         sge.addr   = ib_conn->login_resp_dma;
 752         sge.length = ISER_RX_LOGIN_SIZE;
 753         sge.lkey   = ib_conn->device->mr->lkey;
 754
 755         rx_wr.wr_id   = (unsigned long)ib_conn->login_resp_buf;
 756         rx_wr.sg_list = &sge;
 757         rx_wr.num_sge = 1;
 758         rx_wr.next    = NULL;
 759
 760         ib_conn->post_recv_buf_count++;
 761         ib_ret  = ib_post_recv(ib_conn->qp, &rx_wr, &rx_wr_failed);
 762         if (ib_ret) {
 763                 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
 764                 ib_conn->post_recv_buf_count--;
 765         }
 766         return ib_ret;
 767 }
 768
 769 int iser_post_recvm(struct iser_conn *ib_conn, int count)
 770 {
 771         struct ib_recv_wr *rx_wr, *rx_wr_failed;
 772         int i, ib_ret;
 773         unsigned int my_rx_head = ib_conn->rx_desc_head;
 774         struct iser_rx_desc *rx_desc;
 775
 776         for (rx_wr = ib_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
 777                 rx_desc         = &ib_conn->rx_descs[my_rx_head];
 778                 rx_wr->wr_id    = (unsigned long)rx_desc;
 779                 rx_wr->sg_list  = &rx_desc->rx_sg;
 780                 rx_wr->num_sge  = 1;
 781                 rx_wr->next     = rx_wr + 1;
 782                 my_rx_head = (my_rx_head + 1) & (ISER_QP_MAX_RECV_DTOS - 1);
 783         }
 784
 785         rx_wr--;
 786         rx_wr->next = NULL; /* mark end of work requests list */
 787
 788         ib_conn->post_recv_buf_count += count;
 789         ib_ret  = ib_post_recv(ib_conn->qp, ib_conn->rx_wr, &rx_wr_failed);
 790         if (ib_ret) {
 791                 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
 792                 ib_conn->post_recv_buf_count -= count;
 793         } else
 794                 ib_conn->rx_desc_head = my_rx_head;
 795         return ib_ret;
 796 }
 797
 798
 799 /**
 800  * iser_start_send - Initiate a Send DTO operation
 801  *
 802  * returns 0 on success, -1 on failure
 803  */
 804 int iser_post_send(struct iser_conn *ib_conn, struct iser_tx_desc *tx_desc)
 805 {
 806         int               ib_ret;
 807         struct ib_send_wr send_wr, *send_wr_failed;
 808
 809         ib_dma_sync_single_for_device(ib_conn->device->ib_device,
 810                 tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
 811
 812         send_wr.next       = NULL;
 813         send_wr.wr_id      = (unsigned long)tx_desc;
 814         send_wr.sg_list    = tx_desc->tx_sg;
 815         send_wr.num_sge    = tx_desc->num_sge;
 816         send_wr.opcode     = IB_WR_SEND;
 817         send_wr.send_flags = IB_SEND_SIGNALED;
 818
 819         atomic_inc(&ib_conn->post_send_buf_count);
 820
 821         ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed);
 822         if (ib_ret) {
 823                 iser_err("ib_post_send failed, ret:%d\n", ib_ret);
 824                 atomic_dec(&ib_conn->post_send_buf_count);
 825         }
 826         return ib_ret;
 827 }
 828
 829 static void iser_handle_comp_error(struct iser_tx_desc *desc,
 830                                 struct iser_conn *ib_conn)
 831 {
 832         if (desc && desc->type == ISCSI_TX_DATAOUT)
 833                 kmem_cache_free(ig.desc_cache, desc);
 834
 835         if (ib_conn->post_recv_buf_count == 0 &&
 836             atomic_read(&ib_conn->post_send_buf_count) == 0) {
 837                 /* getting here when the state is UP means that the conn is *
 838                  * being terminated asynchronously from the iSCSI layer's   *
 839                  * perspective.                                             */
 840                 if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
 841                     ISER_CONN_TERMINATING))
 842                         iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
 843                                            ISCSI_ERR_CONN_FAILED);
 844
 845                 /* no more non completed posts to the QP, complete the
 846                  * termination process w.o worrying on disconnect event */
 847                 ib_conn->state = ISER_CONN_DOWN;
 848                 wake_up_interruptible(&ib_conn->wait);
 849         }
 850 }
 851
 852 static int iser_drain_tx_cq(struct iser_device  *device, int cq_index)
 853 {
 854         struct ib_cq  *cq = device->tx_cq[cq_index];
 855         struct ib_wc  wc;
 856         struct iser_tx_desc *tx_desc;
 857         struct iser_conn *ib_conn;
 858         int completed_tx = 0;
 859
 860         while (ib_poll_cq(cq, 1, &wc) == 1) {
 861                 tx_desc = (struct iser_tx_desc *) (unsigned long) wc.wr_id;
 862                 ib_conn = wc.qp->qp_context;
 863                 if (wc.status == IB_WC_SUCCESS) {
 864                         if (wc.opcode == IB_WC_SEND)
 865                                 iser_snd_completion(tx_desc, ib_conn);
 866                         else
 867                                 iser_err("expected opcode %d got %d\n",
 868                                         IB_WC_SEND, wc.opcode);
 869                 } else {
 870                         iser_err("tx id %llx status %d vend_err %x\n",
 871                                 wc.wr_id, wc.status, wc.vendor_err);
 872                         atomic_dec(&ib_conn->post_send_buf_count);
 873                         iser_handle_comp_error(tx_desc, ib_conn);
 874                 }
 875                 completed_tx++;
 876         }
 877         return completed_tx;
 878 }
 879
 880
 881 static void iser_cq_tasklet_fn(unsigned long data)
 882 {
 883         struct iser_cq_desc *cq_desc = (struct iser_cq_desc *)data;
 884         struct iser_device  *device = cq_desc->device;
 885         int cq_index = cq_desc->cq_index;
 886         struct ib_cq         *cq = device->rx_cq[cq_index];
 887          struct ib_wc        wc;
 888          struct iser_rx_desc *desc;
 889          unsigned long       xfer_len;
 890         struct iser_conn *ib_conn;
 891         int completed_tx, completed_rx;
 892         completed_tx = completed_rx = 0;
 893
 894         while (ib_poll_cq(cq, 1, &wc) == 1) {
 895                 desc     = (struct iser_rx_desc *) (unsigned long) wc.wr_id;
 896                 BUG_ON(desc == NULL);
 897                 ib_conn = wc.qp->qp_context;
 898                 if (wc.status == IB_WC_SUCCESS) {
 899                         if (wc.opcode == IB_WC_RECV) {
 900                                 xfer_len = (unsigned long)wc.byte_len;
 901                                 iser_rcv_completion(desc, xfer_len, ib_conn);
 902                         } else
 903                                 iser_err("expected opcode %d got %d\n",
 904                                         IB_WC_RECV, wc.opcode);
 905                 } else {
 906                         if (wc.status != IB_WC_WR_FLUSH_ERR)
 907                                 iser_err("rx id %llx status %d vend_err %x\n",
 908                                         wc.wr_id, wc.status, wc.vendor_err);
 909                         ib_conn->post_recv_buf_count--;
 910                         iser_handle_comp_error(NULL, ib_conn);
 911                 }
 912                 completed_rx++;
 913                 if (!(completed_rx & 63))
 914                         completed_tx += iser_drain_tx_cq(device, cq_index);
 915         }
 916         /* #warning "it is assumed here that arming CQ only once its empty" *
 917          * " would not cause interrupts to be missed"                       */
 918         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
 919
 920         completed_tx += iser_drain_tx_cq(device, cq_index);
 921         iser_dbg("got %d rx %d tx completions\n", completed_rx, completed_tx);
 922 }
 923
 924 static void iser_cq_callback(struct ib_cq *cq, void *cq_context)
 925 {
 926         struct iser_cq_desc *cq_desc = (struct iser_cq_desc *)cq_context;
 927         struct iser_device  *device = cq_desc->device;
 928         int cq_index = cq_desc->cq_index;
 929
 930         tasklet_schedule(&device->cq_tasklet[cq_index]);
 931 }