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