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   1 /*
   2  * Copyright (c) 2005 Cisco Systems.  All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  *
  32  * $Id: ib_srp.c 3932 2005-11-01 17:19:29Z roland $
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/init.h>
  37 #include <linux/slab.h>
  38 #include <linux/err.h>
  39 #include <linux/string.h>
  40 #include <linux/parser.h>
  41 #include <linux/random.h>
  42
  43 #include <asm/atomic.h>
  44
  45 #include <scsi/scsi.h>
  46 #include <scsi/scsi_device.h>
  47 #include <scsi/scsi_dbg.h>
  48 #include <scsi/srp.h>
  49
  50 #include <rdma/ib_cache.h>
  51
  52 #include "ib_srp.h"
  53
  54 #define DRV_NAME        "ib_srp"
  55 #define PFX             DRV_NAME ": "
  56 #define DRV_VERSION     "0.2"
  57 #define DRV_RELDATE     "November 1, 2005"
  58
  59 MODULE_AUTHOR("Roland Dreier");
  60 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
  61                    "v" DRV_VERSION " (" DRV_RELDATE ")");
  62 MODULE_LICENSE("Dual BSD/GPL");
  63
  64 static int topspin_workarounds = 1;
  65
  66 module_param(topspin_workarounds, int, 0444);
  67 MODULE_PARM_DESC(topspin_workarounds,
  68                  "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
  69
  70 static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
  71
  72 static void srp_add_one(struct ib_device *device);
  73 static void srp_remove_one(struct ib_device *device);
  74 static void srp_completion(struct ib_cq *cq, void *target_ptr);
  75 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
  76
  77 static struct ib_client srp_client = {
  78         .name   = "srp",
  79         .add    = srp_add_one,
  80         .remove = srp_remove_one
  81 };
  82
  83 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
  84 {
  85         return (struct srp_target_port *) host->hostdata;
  86 }
  87
  88 static const char *srp_target_info(struct Scsi_Host *host)
  89 {
  90         return host_to_target(host)->target_name;
  91 }
  92
  93 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
  94                                    gfp_t gfp_mask,
  95                                    enum dma_data_direction direction)
  96 {
  97         struct srp_iu *iu;
  98
  99         iu = kmalloc(sizeof *iu, gfp_mask);
 100         if (!iu)
 101                 goto out;
 102
 103         iu->buf = kzalloc(size, gfp_mask);
 104         if (!iu->buf)
 105                 goto out_free_iu;
 106
 107         iu->dma = dma_map_single(host->dev->dma_device, iu->buf, size, direction);
 108         if (dma_mapping_error(iu->dma))
 109                 goto out_free_buf;
 110
 111         iu->size      = size;
 112         iu->direction = direction;
 113
 114         return iu;
 115
 116 out_free_buf:
 117         kfree(iu->buf);
 118 out_free_iu:
 119         kfree(iu);
 120 out:
 121         return NULL;
 122 }
 123
 124 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
 125 {
 126         if (!iu)
 127                 return;
 128
 129         dma_unmap_single(host->dev->dma_device, iu->dma, iu->size, iu->direction);
 130         kfree(iu->buf);
 131         kfree(iu);
 132 }
 133
 134 static void srp_qp_event(struct ib_event *event, void *context)
 135 {
 136         printk(KERN_ERR PFX "QP event %d\n", event->event);
 137 }
 138
 139 static int srp_init_qp(struct srp_target_port *target,
 140                        struct ib_qp *qp)
 141 {
 142         struct ib_qp_attr *attr;
 143         int ret;
 144
 145         attr = kmalloc(sizeof *attr, GFP_KERNEL);
 146         if (!attr)
 147                 return -ENOMEM;
 148
 149         ret = ib_find_cached_pkey(target->srp_host->dev,
 150                                   target->srp_host->port,
 151                                   be16_to_cpu(target->path.pkey),
 152                                   &attr->pkey_index);
 153         if (ret)
 154                 goto out;
 155
 156         attr->qp_state        = IB_QPS_INIT;
 157         attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
 158                                     IB_ACCESS_REMOTE_WRITE);
 159         attr->port_num        = target->srp_host->port;
 160
 161         ret = ib_modify_qp(qp, attr,
 162                            IB_QP_STATE          |
 163                            IB_QP_PKEY_INDEX     |
 164                            IB_QP_ACCESS_FLAGS   |
 165                            IB_QP_PORT);
 166
 167 out:
 168         kfree(attr);
 169         return ret;
 170 }
 171
 172 static int srp_create_target_ib(struct srp_target_port *target)
 173 {
 174         struct ib_qp_init_attr *init_attr;
 175         int ret;
 176
 177         init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
 178         if (!init_attr)
 179                 return -ENOMEM;
 180
 181         target->cq = ib_create_cq(target->srp_host->dev, srp_completion,
 182                                   NULL, target, SRP_CQ_SIZE);
 183         if (IS_ERR(target->cq)) {
 184                 ret = PTR_ERR(target->cq);
 185                 goto out;
 186         }
 187
 188         ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
 189
 190         init_attr->event_handler       = srp_qp_event;
 191         init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
 192         init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
 193         init_attr->cap.max_recv_sge    = 1;
 194         init_attr->cap.max_send_sge    = 1;
 195         init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
 196         init_attr->qp_type             = IB_QPT_RC;
 197         init_attr->send_cq             = target->cq;
 198         init_attr->recv_cq             = target->cq;
 199
 200         target->qp = ib_create_qp(target->srp_host->pd, init_attr);
 201         if (IS_ERR(target->qp)) {
 202                 ret = PTR_ERR(target->qp);
 203                 ib_destroy_cq(target->cq);
 204                 goto out;
 205         }
 206
 207         ret = srp_init_qp(target, target->qp);
 208         if (ret) {
 209                 ib_destroy_qp(target->qp);
 210                 ib_destroy_cq(target->cq);
 211                 goto out;
 212         }
 213
 214 out:
 215         kfree(init_attr);
 216         return ret;
 217 }
 218
 219 static void srp_free_target_ib(struct srp_target_port *target)
 220 {
 221         int i;
 222
 223         ib_destroy_qp(target->qp);
 224         ib_destroy_cq(target->cq);
 225
 226         for (i = 0; i < SRP_RQ_SIZE; ++i)
 227                 srp_free_iu(target->srp_host, target->rx_ring[i]);
 228         for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
 229                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 230 }
 231
 232 static void srp_path_rec_completion(int status,
 233                                     struct ib_sa_path_rec *pathrec,
 234                                     void *target_ptr)
 235 {
 236         struct srp_target_port *target = target_ptr;
 237
 238         target->status = status;
 239         if (status)
 240                 printk(KERN_ERR PFX "Got failed path rec status %d\n", status);
 241         else
 242                 target->path = *pathrec;
 243         complete(&target->done);
 244 }
 245
 246 static int srp_lookup_path(struct srp_target_port *target)
 247 {
 248         target->path.numb_path = 1;
 249
 250         init_completion(&target->done);
 251
 252         target->path_query_id = ib_sa_path_rec_get(target->srp_host->dev,
 253                                                    target->srp_host->port,
 254                                                    &target->path,
 255                                                    IB_SA_PATH_REC_DGID          |
 256                                                    IB_SA_PATH_REC_SGID          |
 257                                                    IB_SA_PATH_REC_NUMB_PATH     |
 258                                                    IB_SA_PATH_REC_PKEY,
 259                                                    SRP_PATH_REC_TIMEOUT_MS,
 260                                                    GFP_KERNEL,
 261                                                    srp_path_rec_completion,
 262                                                    target, &target->path_query);
 263         if (target->path_query_id < 0)
 264                 return target->path_query_id;
 265
 266         wait_for_completion(&target->done);
 267
 268         if (target->status < 0)
 269                 printk(KERN_WARNING PFX "Path record query failed\n");
 270
 271         return target->status;
 272 }
 273
 274 static int srp_send_req(struct srp_target_port *target)
 275 {
 276         struct {
 277                 struct ib_cm_req_param param;
 278                 struct srp_login_req   priv;
 279         } *req = NULL;
 280         int status;
 281
 282         req = kzalloc(sizeof *req, GFP_KERNEL);
 283         if (!req)
 284                 return -ENOMEM;
 285
 286         req->param.primary_path               = &target->path;
 287         req->param.alternate_path             = NULL;
 288         req->param.service_id                 = target->service_id;
 289         req->param.qp_num                     = target->qp->qp_num;
 290         req->param.qp_type                    = target->qp->qp_type;
 291         req->param.private_data               = &req->priv;
 292         req->param.private_data_len           = sizeof req->priv;
 293         req->param.flow_control               = 1;
 294
 295         get_random_bytes(&req->param.starting_psn, 4);
 296         req->param.starting_psn              &= 0xffffff;
 297
 298         /*
 299          * Pick some arbitrary defaults here; we could make these
 300          * module parameters if anyone cared about setting them.
 301          */
 302         req->param.responder_resources        = 4;
 303         req->param.remote_cm_response_timeout = 20;
 304         req->param.local_cm_response_timeout  = 20;
 305         req->param.retry_count                = 7;
 306         req->param.rnr_retry_count            = 7;
 307         req->param.max_cm_retries             = 15;
 308
 309         req->priv.opcode        = SRP_LOGIN_REQ;
 310         req->priv.tag           = 0;
 311         req->priv.req_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
 312         req->priv.req_buf_fmt   = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
 313                                               SRP_BUF_FORMAT_INDIRECT);
 314         memcpy(req->priv.initiator_port_id, target->srp_host->initiator_port_id, 16);
 315         /*
 316          * Topspin/Cisco SRP targets will reject our login unless we
 317          * zero out the first 8 bytes of our initiator port ID.  The
 318          * second 8 bytes must be our local node GUID, but we always
 319          * use that anyway.
 320          */
 321         if (topspin_workarounds && !memcmp(&target->ioc_guid, topspin_oui, 3)) {
 322                 printk(KERN_DEBUG PFX "Topspin/Cisco initiator port ID workaround "
 323                        "activated for target GUID %016llx\n",
 324                        (unsigned long long) be64_to_cpu(target->ioc_guid));
 325                 memset(req->priv.initiator_port_id, 0, 8);
 326         }
 327         memcpy(req->priv.target_port_id,     &target->id_ext, 8);
 328         memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
 329
 330         status = ib_send_cm_req(target->cm_id, &req->param);
 331
 332         kfree(req);
 333
 334         return status;
 335 }
 336
 337 static void srp_disconnect_target(struct srp_target_port *target)
 338 {
 339         /* XXX should send SRP_I_LOGOUT request */
 340
 341         init_completion(&target->done);
 342         ib_send_cm_dreq(target->cm_id, NULL, 0);
 343         wait_for_completion(&target->done);
 344 }
 345
 346 static void srp_remove_work(void *target_ptr)
 347 {
 348         struct srp_target_port *target = target_ptr;
 349
 350         spin_lock_irq(target->scsi_host->host_lock);
 351         if (target->state != SRP_TARGET_DEAD) {
 352                 spin_unlock_irq(target->scsi_host->host_lock);
 353                 scsi_host_put(target->scsi_host);
 354                 return;
 355         }
 356         target->state = SRP_TARGET_REMOVED;
 357         spin_unlock_irq(target->scsi_host->host_lock);
 358
 359         down(&target->srp_host->target_mutex);
 360         list_del(&target->list);
 361         up(&target->srp_host->target_mutex);
 362
 363         scsi_remove_host(target->scsi_host);
 364         ib_destroy_cm_id(target->cm_id);
 365         srp_free_target_ib(target);
 366         scsi_host_put(target->scsi_host);
 367         /* And another put to really free the target port... */
 368         scsi_host_put(target->scsi_host);
 369 }
 370
 371 static int srp_connect_target(struct srp_target_port *target)
 372 {
 373         int ret;
 374
 375         ret = srp_lookup_path(target);
 376         if (ret)
 377                 return ret;
 378
 379         while (1) {
 380                 init_completion(&target->done);
 381                 ret = srp_send_req(target);
 382                 if (ret)
 383                         return ret;
 384                 wait_for_completion(&target->done);
 385
 386                 /*
 387                  * The CM event handling code will set status to
 388                  * SRP_PORT_REDIRECT if we get a port redirect REJ
 389                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
 390                  * redirect REJ back.
 391                  */
 392                 switch (target->status) {
 393                 case 0:
 394                         return 0;
 395
 396                 case SRP_PORT_REDIRECT:
 397                         ret = srp_lookup_path(target);
 398                         if (ret)
 399                                 return ret;
 400                         break;
 401
 402                 case SRP_DLID_REDIRECT:
 403                         break;
 404
 405                 default:
 406                         return target->status;
 407                 }
 408         }
 409 }
 410
 411 static int srp_reconnect_target(struct srp_target_port *target)
 412 {
 413         struct ib_cm_id *new_cm_id;
 414         struct ib_qp_attr qp_attr;
 415         struct srp_request *req;
 416         struct ib_wc wc;
 417         int ret;
 418         int i;
 419
 420         spin_lock_irq(target->scsi_host->host_lock);
 421         if (target->state != SRP_TARGET_LIVE) {
 422                 spin_unlock_irq(target->scsi_host->host_lock);
 423                 return -EAGAIN;
 424         }
 425         target->state = SRP_TARGET_CONNECTING;
 426         spin_unlock_irq(target->scsi_host->host_lock);
 427
 428         srp_disconnect_target(target);
 429         /*
 430          * Now get a new local CM ID so that we avoid confusing the
 431          * target in case things are really fouled up.
 432          */
 433         new_cm_id = ib_create_cm_id(target->srp_host->dev,
 434                                     srp_cm_handler, target);
 435         if (IS_ERR(new_cm_id)) {
 436                 ret = PTR_ERR(new_cm_id);
 437                 goto err;
 438         }
 439         ib_destroy_cm_id(target->cm_id);
 440         target->cm_id = new_cm_id;
 441
 442         qp_attr.qp_state = IB_QPS_RESET;
 443         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
 444         if (ret)
 445                 goto err;
 446
 447         ret = srp_init_qp(target, target->qp);
 448         if (ret)
 449                 goto err;
 450
 451         while (ib_poll_cq(target->cq, 1, &wc) > 0)
 452                 ; /* nothing */
 453
 454         list_for_each_entry(req, &target->req_queue, list) {
 455                 req->scmnd->result = DID_RESET << 16;
 456                 req->scmnd->scsi_done(req->scmnd);
 457         }
 458
 459         target->rx_head  = 0;
 460         target->tx_head  = 0;
 461         target->tx_tail  = 0;
 462         target->req_head = 0;
 463         for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
 464                 target->req_ring[i].next = i + 1;
 465         target->req_ring[SRP_SQ_SIZE - 1].next = -1;
 466         INIT_LIST_HEAD(&target->req_queue);
 467
 468         ret = srp_connect_target(target);
 469         if (ret)
 470                 goto err;
 471
 472         spin_lock_irq(target->scsi_host->host_lock);
 473         if (target->state == SRP_TARGET_CONNECTING) {
 474                 ret = 0;
 475                 target->state = SRP_TARGET_LIVE;
 476         } else
 477                 ret = -EAGAIN;
 478         spin_unlock_irq(target->scsi_host->host_lock);
 479
 480         return ret;
 481
 482 err:
 483         printk(KERN_ERR PFX "reconnect failed (%d), removing target port.\n", ret);
 484
 485         /*
 486          * We couldn't reconnect, so kill our target port off.
 487          * However, we have to defer the real removal because we might
 488          * be in the context of the SCSI error handler now, which
 489          * would deadlock if we call scsi_remove_host().
 490          */
 491         spin_lock_irq(target->scsi_host->host_lock);
 492         if (target->state == SRP_TARGET_CONNECTING) {
 493                 target->state = SRP_TARGET_DEAD;
 494                 INIT_WORK(&target->work, srp_remove_work, target);
 495                 schedule_work(&target->work);
 496         }
 497         spin_unlock_irq(target->scsi_host->host_lock);
 498
 499         return ret;
 500 }
 501
 502 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
 503                         struct srp_request *req)
 504 {
 505         struct srp_cmd *cmd = req->cmd->buf;
 506         int len;
 507         u8 fmt;
 508
 509         if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
 510                 return sizeof (struct srp_cmd);
 511
 512         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
 513             scmnd->sc_data_direction != DMA_TO_DEVICE) {
 514                 printk(KERN_WARNING PFX "Unhandled data direction %d\n",
 515                        scmnd->sc_data_direction);
 516                 return -EINVAL;
 517         }
 518
 519         if (scmnd->use_sg) {
 520                 struct scatterlist *scat = scmnd->request_buffer;
 521                 int n;
 522                 int i;
 523
 524                 n = dma_map_sg(target->srp_host->dev->dma_device,
 525                                scat, scmnd->use_sg, scmnd->sc_data_direction);
 526
 527                 if (n == 1) {
 528                         struct srp_direct_buf *buf = (void *) cmd->add_data;
 529
 530                         fmt = SRP_DATA_DESC_DIRECT;
 531
 532                         buf->va  = cpu_to_be64(sg_dma_address(scat));
 533                         buf->key = cpu_to_be32(target->srp_host->mr->rkey);
 534                         buf->len = cpu_to_be32(sg_dma_len(scat));
 535
 536                         len = sizeof (struct srp_cmd) +
 537                                 sizeof (struct srp_direct_buf);
 538                 } else {
 539                         struct srp_indirect_buf *buf = (void *) cmd->add_data;
 540                         u32 datalen = 0;
 541
 542                         fmt = SRP_DATA_DESC_INDIRECT;
 543
 544                         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 545                                 cmd->data_out_desc_cnt = n;
 546                         else
 547                                 cmd->data_in_desc_cnt = n;
 548
 549                         buf->table_desc.va  = cpu_to_be64(req->cmd->dma +
 550                                                           sizeof *cmd +
 551                                                           sizeof *buf);
 552                         buf->table_desc.key =
 553                                 cpu_to_be32(target->srp_host->mr->rkey);
 554                         buf->table_desc.len =
 555                                 cpu_to_be32(n * sizeof (struct srp_direct_buf));
 556
 557                         for (i = 0; i < n; ++i) {
 558                                 buf->desc_list[i].va  = cpu_to_be64(sg_dma_address(&scat[i]));
 559                                 buf->desc_list[i].key =
 560                                         cpu_to_be32(target->srp_host->mr->rkey);
 561                                 buf->desc_list[i].len = cpu_to_be32(sg_dma_len(&scat[i]));
 562
 563                                 datalen += sg_dma_len(&scat[i]);
 564                         }
 565
 566                         buf->len = cpu_to_be32(datalen);
 567
 568                         len = sizeof (struct srp_cmd) +
 569                                 sizeof (struct srp_indirect_buf) +
 570                                 n * sizeof (struct srp_direct_buf);
 571                 }
 572         } else {
 573                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 574                 dma_addr_t dma;
 575
 576                 dma = dma_map_single(target->srp_host->dev->dma_device,
 577                                      scmnd->request_buffer, scmnd->request_bufflen,
 578                                      scmnd->sc_data_direction);
 579                 if (dma_mapping_error(dma)) {
 580                         printk(KERN_WARNING PFX "unable to map %p/%d (dir %d)\n",
 581                                scmnd->request_buffer, (int) scmnd->request_bufflen,
 582                                scmnd->sc_data_direction);
 583                         return -EINVAL;
 584                 }
 585
 586                 pci_unmap_addr_set(req, direct_mapping, dma);
 587
 588                 buf->va  = cpu_to_be64(dma);
 589                 buf->key = cpu_to_be32(target->srp_host->mr->rkey);
 590                 buf->len = cpu_to_be32(scmnd->request_bufflen);
 591
 592                 fmt = SRP_DATA_DESC_DIRECT;
 593
 594                 len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
 595         }
 596
 597         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 598                 cmd->buf_fmt = fmt << 4;
 599         else
 600                 cmd->buf_fmt = fmt;
 601
 602
 603         return len;
 604 }
 605
 606 static void srp_unmap_data(struct scsi_cmnd *scmnd,
 607                            struct srp_target_port *target,
 608                            struct srp_request *req)
 609 {
 610         if (!scmnd->request_buffer ||
 611             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
 612              scmnd->sc_data_direction != DMA_FROM_DEVICE))
 613             return;
 614
 615         if (scmnd->use_sg)
 616                 dma_unmap_sg(target->srp_host->dev->dma_device,
 617                              (struct scatterlist *) scmnd->request_buffer,
 618                              scmnd->use_sg, scmnd->sc_data_direction);
 619         else
 620                 dma_unmap_single(target->srp_host->dev->dma_device,
 621                                  pci_unmap_addr(req, direct_mapping),
 622                                  scmnd->request_bufflen,
 623                                  scmnd->sc_data_direction);
 624 }
 625
 626 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
 627 {
 628         struct srp_request *req;
 629         struct scsi_cmnd *scmnd;
 630         unsigned long flags;
 631         s32 delta;
 632
 633         delta = (s32) be32_to_cpu(rsp->req_lim_delta);
 634
 635         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 636
 637         target->req_lim += delta;
 638
 639         req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
 640
 641         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
 642                 if (be32_to_cpu(rsp->resp_data_len) < 4)
 643                         req->tsk_status = -1;
 644                 else
 645                         req->tsk_status = rsp->data[3];
 646                 complete(&req->done);
 647         } else {
 648                 scmnd         = req->scmnd;
 649                 if (!scmnd)
 650                         printk(KERN_ERR "Null scmnd for RSP w/tag %016llx\n",
 651                                (unsigned long long) rsp->tag);
 652                 scmnd->result = rsp->status;
 653
 654                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
 655                         memcpy(scmnd->sense_buffer, rsp->data +
 656                                be32_to_cpu(rsp->resp_data_len),
 657                                min_t(int, be32_to_cpu(rsp->sense_data_len),
 658                                      SCSI_SENSE_BUFFERSIZE));
 659                 }
 660
 661                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
 662                         scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
 663                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
 664                         scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
 665
 666                 srp_unmap_data(scmnd, target, req);
 667
 668                 if (!req->tsk_mgmt) {
 669                         req->scmnd = NULL;
 670                         scmnd->host_scribble = (void *) -1L;
 671                         scmnd->scsi_done(scmnd);
 672
 673                         list_del(&req->list);
 674                         req->next = target->req_head;
 675                         target->req_head = rsp->tag & ~SRP_TAG_TSK_MGMT;
 676                 } else
 677                         req->cmd_done = 1;
 678         }
 679
 680         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 681 }
 682
 683 static void srp_reconnect_work(void *target_ptr)
 684 {
 685         struct srp_target_port *target = target_ptr;
 686
 687         srp_reconnect_target(target);
 688 }
 689
 690 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 691 {
 692         struct srp_iu *iu;
 693         u8 opcode;
 694
 695         iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
 696
 697         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 698                                 target->max_ti_iu_len, DMA_FROM_DEVICE);
 699
 700         opcode = *(u8 *) iu->buf;
 701
 702         if (0) {
 703                 int i;
 704
 705                 printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
 706
 707                 for (i = 0; i < wc->byte_len; ++i) {
 708                         if (i % 8 == 0)
 709                                 printk(KERN_ERR "  [%02x] ", i);
 710                         printk(" %02x", ((u8 *) iu->buf)[i]);
 711                         if ((i + 1) % 8 == 0)
 712                                 printk("\n");
 713                 }
 714
 715                 if (wc->byte_len % 8)
 716                         printk("\n");
 717         }
 718
 719         switch (opcode) {
 720         case SRP_RSP:
 721                 srp_process_rsp(target, iu->buf);
 722                 break;
 723
 724         case SRP_T_LOGOUT:
 725                 /* XXX Handle target logout */
 726                 printk(KERN_WARNING PFX "Got target logout request\n");
 727                 break;
 728
 729         default:
 730                 printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
 731                 break;
 732         }
 733
 734         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 735                                    target->max_ti_iu_len, DMA_FROM_DEVICE);
 736 }
 737
 738 static void srp_completion(struct ib_cq *cq, void *target_ptr)
 739 {
 740         struct srp_target_port *target = target_ptr;
 741         struct ib_wc wc;
 742         unsigned long flags;
 743
 744         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
 745         while (ib_poll_cq(cq, 1, &wc) > 0) {
 746                 if (wc.status) {
 747                         printk(KERN_ERR PFX "failed %s status %d\n",
 748                                wc.wr_id & SRP_OP_RECV ? "receive" : "send",
 749                                wc.status);
 750                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 751                         if (target->state == SRP_TARGET_LIVE)
 752                                 schedule_work(&target->work);
 753                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 754                         break;
 755                 }
 756
 757                 if (wc.wr_id & SRP_OP_RECV)
 758                         srp_handle_recv(target, &wc);
 759                 else
 760                         ++target->tx_tail;
 761         }
 762 }
 763
 764 static int __srp_post_recv(struct srp_target_port *target)
 765 {
 766         struct srp_iu *iu;
 767         struct ib_sge list;
 768         struct ib_recv_wr wr, *bad_wr;
 769         unsigned int next;
 770         int ret;
 771
 772         next     = target->rx_head & (SRP_RQ_SIZE - 1);
 773         wr.wr_id = next | SRP_OP_RECV;
 774         iu       = target->rx_ring[next];
 775
 776         list.addr   = iu->dma;
 777         list.length = iu->size;
 778         list.lkey   = target->srp_host->mr->lkey;
 779
 780         wr.next     = NULL;
 781         wr.sg_list  = &list;
 782         wr.num_sge  = 1;
 783
 784         ret = ib_post_recv(target->qp, &wr, &bad_wr);
 785         if (!ret)
 786                 ++target->rx_head;
 787
 788         return ret;
 789 }
 790
 791 static int srp_post_recv(struct srp_target_port *target)
 792 {
 793         unsigned long flags;
 794         int ret;
 795
 796         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 797         ret = __srp_post_recv(target);
 798         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 799
 800         return ret;
 801 }
 802
 803 /*
 804  * Must be called with target->scsi_host->host_lock held to protect
 805  * req_lim and tx_head.  Lock cannot be dropped between call here and
 806  * call to __srp_post_send().
 807  */
 808 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
 809 {
 810         if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
 811                 return NULL;
 812
 813         if (unlikely(target->req_lim < 1)) {
 814                 if (printk_ratelimit())
 815                         printk(KERN_DEBUG PFX "Target has req_lim %d\n",
 816                                target->req_lim);
 817                 return NULL;
 818         }
 819
 820         return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
 821 }
 822
 823 /*
 824  * Must be called with target->scsi_host->host_lock held to protect
 825  * req_lim and tx_head.
 826  */
 827 static int __srp_post_send(struct srp_target_port *target,
 828                            struct srp_iu *iu, int len)
 829 {
 830         struct ib_sge list;
 831         struct ib_send_wr wr, *bad_wr;
 832         int ret = 0;
 833
 834         list.addr   = iu->dma;
 835         list.length = len;
 836         list.lkey   = target->srp_host->mr->lkey;
 837
 838         wr.next       = NULL;
 839         wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
 840         wr.sg_list    = &list;
 841         wr.num_sge    = 1;
 842         wr.opcode     = IB_WR_SEND;
 843         wr.send_flags = IB_SEND_SIGNALED;
 844
 845         ret = ib_post_send(target->qp, &wr, &bad_wr);
 846
 847         if (!ret) {
 848                 ++target->tx_head;
 849                 --target->req_lim;
 850         }
 851
 852         return ret;
 853 }
 854
 855 static int srp_queuecommand(struct scsi_cmnd *scmnd,
 856                             void (*done)(struct scsi_cmnd *))
 857 {
 858         struct srp_target_port *target = host_to_target(scmnd->device->host);
 859         struct srp_request *req;
 860         struct srp_iu *iu;
 861         struct srp_cmd *cmd;
 862         long req_index;
 863         int len;
 864
 865         if (target->state == SRP_TARGET_CONNECTING)
 866                 goto err;
 867
 868         if (target->state == SRP_TARGET_DEAD ||
 869             target->state == SRP_TARGET_REMOVED) {
 870                 scmnd->result = DID_BAD_TARGET << 16;
 871                 done(scmnd);
 872                 return 0;
 873         }
 874
 875         iu = __srp_get_tx_iu(target);
 876         if (!iu)
 877                 goto err;
 878
 879         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 880                                 SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 881
 882         req_index = target->req_head;
 883
 884         scmnd->scsi_done     = done;
 885         scmnd->result        = 0;
 886         scmnd->host_scribble = (void *) req_index;
 887
 888         cmd = iu->buf;
 889         memset(cmd, 0, sizeof *cmd);
 890
 891         cmd->opcode = SRP_CMD;
 892         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
 893         cmd->tag    = req_index;
 894         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
 895
 896         req = &target->req_ring[req_index];
 897
 898         req->scmnd    = scmnd;
 899         req->cmd      = iu;
 900         req->cmd_done = 0;
 901         req->tsk_mgmt = NULL;
 902
 903         len = srp_map_data(scmnd, target, req);
 904         if (len < 0) {
 905                 printk(KERN_ERR PFX "Failed to map data\n");
 906                 goto err;
 907         }
 908
 909         if (__srp_post_recv(target)) {
 910                 printk(KERN_ERR PFX "Recv failed\n");
 911                 goto err_unmap;
 912         }
 913
 914         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 915                                    SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 916
 917         if (__srp_post_send(target, iu, len)) {
 918                 printk(KERN_ERR PFX "Send failed\n");
 919                 goto err_unmap;
 920         }
 921
 922         target->req_head = req->next;
 923         list_add_tail(&req->list, &target->req_queue);
 924
 925         return 0;
 926
 927 err_unmap:
 928         srp_unmap_data(scmnd, target, req);
 929
 930 err:
 931         return SCSI_MLQUEUE_HOST_BUSY;
 932 }
 933
 934 static int srp_alloc_iu_bufs(struct srp_target_port *target)
 935 {
 936         int i;
 937
 938         for (i = 0; i < SRP_RQ_SIZE; ++i) {
 939                 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
 940                                                   target->max_ti_iu_len,
 941                                                   GFP_KERNEL, DMA_FROM_DEVICE);
 942                 if (!target->rx_ring[i])
 943                         goto err;
 944         }
 945
 946         for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
 947                 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
 948                                                   SRP_MAX_IU_LEN,
 949                                                   GFP_KERNEL, DMA_TO_DEVICE);
 950                 if (!target->tx_ring[i])
 951                         goto err;
 952         }
 953
 954         return 0;
 955
 956 err:
 957         for (i = 0; i < SRP_RQ_SIZE; ++i) {
 958                 srp_free_iu(target->srp_host, target->rx_ring[i]);
 959                 target->rx_ring[i] = NULL;
 960         }
 961
 962         for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
 963                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 964                 target->tx_ring[i] = NULL;
 965         }
 966
 967         return -ENOMEM;
 968 }
 969
 970 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
 971                                struct ib_cm_event *event,
 972                                struct srp_target_port *target)
 973 {
 974         struct ib_class_port_info *cpi;
 975         int opcode;
 976
 977         switch (event->param.rej_rcvd.reason) {
 978         case IB_CM_REJ_PORT_CM_REDIRECT:
 979                 cpi = event->param.rej_rcvd.ari;
 980                 target->path.dlid = cpi->redirect_lid;
 981                 target->path.pkey = cpi->redirect_pkey;
 982                 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
 983                 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
 984
 985                 target->status = target->path.dlid ?
 986                         SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
 987                 break;
 988
 989         case IB_CM_REJ_PORT_REDIRECT:
 990                 if (topspin_workarounds &&
 991                     !memcmp(&target->ioc_guid, topspin_oui, 3)) {
 992                         /*
 993                          * Topspin/Cisco SRP gateways incorrectly send
 994                          * reject reason code 25 when they mean 24
 995                          * (port redirect).
 996                          */
 997                         memcpy(target->path.dgid.raw,
 998                                event->param.rej_rcvd.ari, 16);
 999
1000                         printk(KERN_DEBUG PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1001                                (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1002                                (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1003
1004                         target->status = SRP_PORT_REDIRECT;
1005                 } else {
1006                         printk(KERN_WARNING "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1007                         target->status = -ECONNRESET;
1008                 }
1009                 break;
1010
1011         case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1012                 printk(KERN_WARNING "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1013                 target->status = -ECONNRESET;
1014                 break;
1015
1016         case IB_CM_REJ_CONSUMER_DEFINED:
1017                 opcode = *(u8 *) event->private_data;
1018                 if (opcode == SRP_LOGIN_REJ) {
1019                         struct srp_login_rej *rej = event->private_data;
1020                         u32 reason = be32_to_cpu(rej->reason);
1021
1022                         if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1023                                 printk(KERN_WARNING PFX
1024                                        "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1025                         else
1026                                 printk(KERN_WARNING PFX
1027                                        "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1028                 } else
1029                         printk(KERN_WARNING "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1030                                " opcode 0x%02x\n", opcode);
1031                 target->status = -ECONNRESET;
1032                 break;
1033
1034         default:
1035                 printk(KERN_WARNING "  REJ reason 0x%x\n",
1036                        event->param.rej_rcvd.reason);
1037                 target->status = -ECONNRESET;
1038         }
1039 }
1040
1041 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1042 {
1043         struct srp_target_port *target = cm_id->context;
1044         struct ib_qp_attr *qp_attr = NULL;
1045         int attr_mask = 0;
1046         int comp = 0;
1047         int opcode = 0;
1048
1049         switch (event->event) {
1050         case IB_CM_REQ_ERROR:
1051                 printk(KERN_DEBUG PFX "Sending CM REQ failed\n");
1052                 comp = 1;
1053                 target->status = -ECONNRESET;
1054                 break;
1055
1056         case IB_CM_REP_RECEIVED:
1057                 comp = 1;
1058                 opcode = *(u8 *) event->private_data;
1059
1060                 if (opcode == SRP_LOGIN_RSP) {
1061                         struct srp_login_rsp *rsp = event->private_data;
1062
1063                         target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1064                         target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1065
1066                         target->scsi_host->can_queue = min(target->req_lim,
1067                                                            target->scsi_host->can_queue);
1068                 } else {
1069                         printk(KERN_WARNING PFX "Unhandled RSP opcode %#x\n", opcode);
1070                         target->status = -ECONNRESET;
1071                         break;
1072                 }
1073
1074                 target->status = srp_alloc_iu_bufs(target);
1075                 if (target->status)
1076                         break;
1077
1078                 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1079                 if (!qp_attr) {
1080                         target->status = -ENOMEM;
1081                         break;
1082                 }
1083
1084                 qp_attr->qp_state = IB_QPS_RTR;
1085                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1086                 if (target->status)
1087                         break;
1088
1089                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1090                 if (target->status)
1091                         break;
1092
1093                 target->status = srp_post_recv(target);
1094                 if (target->status)
1095                         break;
1096
1097                 qp_attr->qp_state = IB_QPS_RTS;
1098                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1099                 if (target->status)
1100                         break;
1101
1102                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1103                 if (target->status)
1104                         break;
1105
1106                 target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1107                 if (target->status)
1108                         break;
1109
1110                 break;
1111
1112         case IB_CM_REJ_RECEIVED:
1113                 printk(KERN_DEBUG PFX "REJ received\n");
1114                 comp = 1;
1115
1116                 srp_cm_rej_handler(cm_id, event, target);
1117                 break;
1118
1119         case IB_CM_MRA_RECEIVED:
1120                 printk(KERN_ERR PFX "MRA received\n");
1121                 break;
1122
1123         case IB_CM_DREP_RECEIVED:
1124                 break;
1125
1126         case IB_CM_TIMEWAIT_EXIT:
1127                 printk(KERN_ERR PFX "connection closed\n");
1128
1129                 comp = 1;
1130                 target->status = 0;
1131                 break;
1132
1133         default:
1134                 printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
1135                 break;
1136         }
1137
1138         if (comp)
1139                 complete(&target->done);
1140
1141         kfree(qp_attr);
1142
1143         return 0;
1144 }
1145
1146 static int srp_send_tsk_mgmt(struct scsi_cmnd *scmnd, u8 func)
1147 {
1148         struct srp_target_port *target = host_to_target(scmnd->device->host);
1149         struct srp_request *req;
1150         struct srp_iu *iu;
1151         struct srp_tsk_mgmt *tsk_mgmt;
1152         int req_index;
1153         int ret = FAILED;
1154
1155         spin_lock_irq(target->scsi_host->host_lock);
1156
1157         if (scmnd->host_scribble == (void *) -1L)
1158                 goto out;
1159
1160         req_index = (long) scmnd->host_scribble;
1161         printk(KERN_ERR "Abort for req_index %d\n", req_index);
1162
1163         req = &target->req_ring[req_index];
1164         init_completion(&req->done);
1165
1166         iu = __srp_get_tx_iu(target);
1167         if (!iu)
1168                 goto out;
1169
1170         tsk_mgmt = iu->buf;
1171         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1172
1173         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1174         tsk_mgmt->lun           = cpu_to_be64((u64) scmnd->device->lun << 48);
1175         tsk_mgmt->tag           = req_index | SRP_TAG_TSK_MGMT;
1176         tsk_mgmt->tsk_mgmt_func = func;
1177         tsk_mgmt->task_tag      = req_index;
1178
1179         if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1180                 goto out;
1181
1182         req->tsk_mgmt = iu;
1183
1184         spin_unlock_irq(target->scsi_host->host_lock);
1185         if (!wait_for_completion_timeout(&req->done,
1186                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1187                 return FAILED;
1188         spin_lock_irq(target->scsi_host->host_lock);
1189
1190         if (req->cmd_done) {
1191                 list_del(&req->list);
1192                 req->next = target->req_head;
1193                 target->req_head = req_index;
1194
1195                 scmnd->scsi_done(scmnd);
1196         } else if (!req->tsk_status) {
1197                 scmnd->result = DID_ABORT << 16;
1198                 ret = SUCCESS;
1199         }
1200
1201 out:
1202         spin_unlock_irq(target->scsi_host->host_lock);
1203         return ret;
1204 }
1205
1206 static int srp_abort(struct scsi_cmnd *scmnd)
1207 {
1208         printk(KERN_ERR "SRP abort called\n");
1209
1210         return srp_send_tsk_mgmt(scmnd, SRP_TSK_ABORT_TASK);
1211 }
1212
1213 static int srp_reset_device(struct scsi_cmnd *scmnd)
1214 {
1215         printk(KERN_ERR "SRP reset_device called\n");
1216
1217         return srp_send_tsk_mgmt(scmnd, SRP_TSK_LUN_RESET);
1218 }
1219
1220 static int srp_reset_host(struct scsi_cmnd *scmnd)
1221 {
1222         struct srp_target_port *target = host_to_target(scmnd->device->host);
1223         int ret = FAILED;
1224
1225         printk(KERN_ERR PFX "SRP reset_host called\n");
1226
1227         if (!srp_reconnect_target(target))
1228                 ret = SUCCESS;
1229
1230         return ret;
1231 }
1232
1233 static struct scsi_host_template srp_template = {
1234         .module                         = THIS_MODULE,
1235         .name                           = DRV_NAME,
1236         .info                           = srp_target_info,
1237         .queuecommand                   = srp_queuecommand,
1238         .eh_abort_handler               = srp_abort,
1239         .eh_device_reset_handler        = srp_reset_device,
1240         .eh_host_reset_handler          = srp_reset_host,
1241         .can_queue                      = SRP_SQ_SIZE,
1242         .this_id                        = -1,
1243         .sg_tablesize                   = SRP_MAX_INDIRECT,
1244         .cmd_per_lun                    = SRP_SQ_SIZE,
1245         .use_clustering                 = ENABLE_CLUSTERING
1246 };
1247
1248 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1249 {
1250         sprintf(target->target_name, "SRP.T10:%016llX",
1251                  (unsigned long long) be64_to_cpu(target->id_ext));
1252
1253         if (scsi_add_host(target->scsi_host, host->dev->dma_device))
1254                 return -ENODEV;
1255
1256         down(&host->target_mutex);
1257         list_add_tail(&target->list, &host->target_list);
1258         up(&host->target_mutex);
1259
1260         target->state = SRP_TARGET_LIVE;
1261
1262         /* XXX: are we supposed to have a definition of SCAN_WILD_CARD ?? */
1263         scsi_scan_target(&target->scsi_host->shost_gendev,
1264                          0, target->scsi_id, ~0, 0);
1265
1266         return 0;
1267 }
1268
1269 static void srp_release_class_dev(struct class_device *class_dev)
1270 {
1271         struct srp_host *host =
1272                 container_of(class_dev, struct srp_host, class_dev);
1273
1274         complete(&host->released);
1275 }
1276
1277 static struct class srp_class = {
1278         .name    = "infiniband_srp",
1279         .release = srp_release_class_dev
1280 };
1281
1282 /*
1283  * Target ports are added by writing
1284  *
1285  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1286  *     pkey=<P_Key>,service_id=<service ID>
1287  *
1288  * to the add_target sysfs attribute.
1289  */
1290 enum {
1291         SRP_OPT_ERR             = 0,
1292         SRP_OPT_ID_EXT          = 1 << 0,
1293         SRP_OPT_IOC_GUID        = 1 << 1,
1294         SRP_OPT_DGID            = 1 << 2,
1295         SRP_OPT_PKEY            = 1 << 3,
1296         SRP_OPT_SERVICE_ID      = 1 << 4,
1297         SRP_OPT_MAX_SECT        = 1 << 5,
1298         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1299                                    SRP_OPT_IOC_GUID     |
1300                                    SRP_OPT_DGID         |
1301                                    SRP_OPT_PKEY         |
1302                                    SRP_OPT_SERVICE_ID),
1303 };
1304
1305 static match_table_t srp_opt_tokens = {
1306         { SRP_OPT_ID_EXT,       "id_ext=%s"     },
1307         { SRP_OPT_IOC_GUID,     "ioc_guid=%s"   },
1308         { SRP_OPT_DGID,         "dgid=%s"       },
1309         { SRP_OPT_PKEY,         "pkey=%x"       },
1310         { SRP_OPT_SERVICE_ID,   "service_id=%s" },
1311         { SRP_OPT_MAX_SECT,     "max_sect=%d"   },
1312         { SRP_OPT_ERR,          NULL            }
1313 };
1314
1315 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1316 {
1317         char *options, *sep_opt;
1318         char *p;
1319         char dgid[3];
1320         substring_t args[MAX_OPT_ARGS];
1321         int opt_mask = 0;
1322         int token;
1323         int ret = -EINVAL;
1324         int i;
1325
1326         options = kstrdup(buf, GFP_KERNEL);
1327         if (!options)
1328                 return -ENOMEM;
1329
1330         sep_opt = options;
1331         while ((p = strsep(&sep_opt, ",")) != NULL) {
1332                 if (!*p)
1333                         continue;
1334
1335                 token = match_token(p, srp_opt_tokens, args);
1336                 opt_mask |= token;
1337
1338                 switch (token) {
1339                 case SRP_OPT_ID_EXT:
1340                         p = match_strdup(args);
1341                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1342                         kfree(p);
1343                         break;
1344
1345                 case SRP_OPT_IOC_GUID:
1346                         p = match_strdup(args);
1347                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1348                         kfree(p);
1349                         break;
1350
1351                 case SRP_OPT_DGID:
1352                         p = match_strdup(args);
1353                         if (strlen(p) != 32) {
1354                                 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1355                                 goto out;
1356                         }
1357
1358                         for (i = 0; i < 16; ++i) {
1359                                 strlcpy(dgid, p + i * 2, 3);
1360                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1361                         }
1362                         break;
1363
1364                 case SRP_OPT_PKEY:
1365                         if (match_hex(args, &token)) {
1366                                 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1367                                 goto out;
1368                         }
1369                         target->path.pkey = cpu_to_be16(token);
1370                         break;
1371
1372                 case SRP_OPT_SERVICE_ID:
1373                         p = match_strdup(args);
1374                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1375                         kfree(p);
1376                         break;
1377
1378                 case SRP_OPT_MAX_SECT:
1379                         if (match_int(args, &token)) {
1380                                 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1381                                 goto out;
1382                         }
1383                         target->scsi_host->max_sectors = token;
1384                         break;
1385
1386                 default:
1387                         printk(KERN_WARNING PFX "unknown parameter or missing value "
1388                                "'%s' in target creation request\n", p);
1389                         goto out;
1390                 }
1391         }
1392
1393         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1394                 ret = 0;
1395         else
1396                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1397                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1398                             !(srp_opt_tokens[i].token & opt_mask))
1399                                 printk(KERN_WARNING PFX "target creation request is "
1400                                        "missing parameter '%s'\n",
1401                                        srp_opt_tokens[i].pattern);
1402
1403 out:
1404         kfree(options);
1405         return ret;
1406 }
1407
1408 static ssize_t srp_create_target(struct class_device *class_dev,
1409                                  const char *buf, size_t count)
1410 {
1411         struct srp_host *host =
1412                 container_of(class_dev, struct srp_host, class_dev);
1413         struct Scsi_Host *target_host;
1414         struct srp_target_port *target;
1415         int ret;
1416         int i;
1417
1418         target_host = scsi_host_alloc(&srp_template,
1419                                       sizeof (struct srp_target_port));
1420         if (!target_host)
1421                 return -ENOMEM;
1422
1423         target_host->max_lun = SRP_MAX_LUN;
1424
1425         target = host_to_target(target_host);
1426         memset(target, 0, sizeof *target);
1427
1428         target->scsi_host  = target_host;
1429         target->srp_host   = host;
1430
1431         INIT_WORK(&target->work, srp_reconnect_work, target);
1432
1433         for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
1434                 target->req_ring[i].next = i + 1;
1435         target->req_ring[SRP_SQ_SIZE - 1].next = -1;
1436         INIT_LIST_HEAD(&target->req_queue);
1437
1438         ret = srp_parse_options(buf, target);
1439         if (ret)
1440                 goto err;
1441
1442         ib_get_cached_gid(host->dev, host->port, 0, &target->path.sgid);
1443
1444         printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1445                "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1446                (unsigned long long) be64_to_cpu(target->id_ext),
1447                (unsigned long long) be64_to_cpu(target->ioc_guid),
1448                be16_to_cpu(target->path.pkey),
1449                (unsigned long long) be64_to_cpu(target->service_id),
1450                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
1451                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
1452                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
1453                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
1454                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
1455                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
1456                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
1457                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
1458
1459         ret = srp_create_target_ib(target);
1460         if (ret)
1461                 goto err;
1462
1463         target->cm_id = ib_create_cm_id(host->dev, srp_cm_handler, target);
1464         if (IS_ERR(target->cm_id)) {
1465                 ret = PTR_ERR(target->cm_id);
1466                 goto err_free;
1467         }
1468
1469         ret = srp_connect_target(target);
1470         if (ret) {
1471                 printk(KERN_ERR PFX "Connection failed\n");
1472                 goto err_cm_id;
1473         }
1474
1475         ret = srp_add_target(host, target);
1476         if (ret)
1477                 goto err_disconnect;
1478
1479         return count;
1480
1481 err_disconnect:
1482         srp_disconnect_target(target);
1483
1484 err_cm_id:
1485         ib_destroy_cm_id(target->cm_id);
1486
1487 err_free:
1488         srp_free_target_ib(target);
1489
1490 err:
1491         scsi_host_put(target_host);
1492
1493         return ret;
1494 }
1495
1496 static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1497
1498 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
1499 {
1500         struct srp_host *host =
1501                 container_of(class_dev, struct srp_host, class_dev);
1502
1503         return sprintf(buf, "%s\n", host->dev->name);
1504 }
1505
1506 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1507
1508 static ssize_t show_port(struct class_device *class_dev, char *buf)
1509 {
1510         struct srp_host *host =
1511                 container_of(class_dev, struct srp_host, class_dev);
1512
1513         return sprintf(buf, "%d\n", host->port);
1514 }
1515
1516 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1517
1518 static struct srp_host *srp_add_port(struct ib_device *device,
1519                                      __be64 node_guid, u8 port)
1520 {
1521         struct srp_host *host;
1522
1523         host = kzalloc(sizeof *host, GFP_KERNEL);
1524         if (!host)
1525                 return NULL;
1526
1527         INIT_LIST_HEAD(&host->target_list);
1528         init_MUTEX(&host->target_mutex);
1529         init_completion(&host->released);
1530         host->dev  = device;
1531         host->port = port;
1532
1533         host->initiator_port_id[7] = port;
1534         memcpy(host->initiator_port_id + 8, &node_guid, 8);
1535
1536         host->pd   = ib_alloc_pd(device);
1537         if (IS_ERR(host->pd))
1538                 goto err_free;
1539
1540         host->mr   = ib_get_dma_mr(host->pd,
1541                                    IB_ACCESS_LOCAL_WRITE |
1542                                    IB_ACCESS_REMOTE_READ |
1543                                    IB_ACCESS_REMOTE_WRITE);
1544         if (IS_ERR(host->mr))
1545                 goto err_pd;
1546
1547         host->class_dev.class = &srp_class;
1548         host->class_dev.dev   = device->dma_device;
1549         snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
1550                  device->name, port);
1551
1552         if (class_device_register(&host->class_dev))
1553                 goto err_mr;
1554         if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
1555                 goto err_class;
1556         if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
1557                 goto err_class;
1558         if (class_device_create_file(&host->class_dev, &class_device_attr_port))
1559                 goto err_class;
1560
1561         return host;
1562
1563 err_class:
1564         class_device_unregister(&host->class_dev);
1565
1566 err_mr:
1567         ib_dereg_mr(host->mr);
1568
1569 err_pd:
1570         ib_dealloc_pd(host->pd);
1571
1572 err_free:
1573         kfree(host);
1574
1575         return NULL;
1576 }
1577
1578 static void srp_add_one(struct ib_device *device)
1579 {
1580         struct list_head *dev_list;
1581         struct srp_host *host;
1582         struct ib_device_attr *dev_attr;
1583         int s, e, p;
1584
1585         dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
1586         if (!dev_attr)
1587                 return;
1588
1589         if (ib_query_device(device, dev_attr)) {
1590                 printk(KERN_WARNING PFX "Couldn't query node GUID for %s.\n",
1591                        device->name);
1592                 goto out;
1593         }
1594
1595         dev_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
1596         if (!dev_list)
1597                 goto out;
1598
1599         INIT_LIST_HEAD(dev_list);
1600
1601         if (device->node_type == IB_NODE_SWITCH) {
1602                 s = 0;
1603                 e = 0;
1604         } else {
1605                 s = 1;
1606                 e = device->phys_port_cnt;
1607         }
1608
1609         for (p = s; p <= e; ++p) {
1610                 host = srp_add_port(device, dev_attr->node_guid, p);
1611                 if (host)
1612                         list_add_tail(&host->list, dev_list);
1613         }
1614
1615         ib_set_client_data(device, &srp_client, dev_list);
1616
1617 out:
1618         kfree(dev_attr);
1619 }
1620
1621 static void srp_remove_one(struct ib_device *device)
1622 {
1623         struct list_head *dev_list;
1624         struct srp_host *host, *tmp_host;
1625         LIST_HEAD(target_list);
1626         struct srp_target_port *target, *tmp_target;
1627         unsigned long flags;
1628
1629         dev_list = ib_get_client_data(device, &srp_client);
1630
1631         list_for_each_entry_safe(host, tmp_host, dev_list, list) {
1632                 class_device_unregister(&host->class_dev);
1633                 /*
1634                  * Wait for the sysfs entry to go away, so that no new
1635                  * target ports can be created.
1636                  */
1637                 wait_for_completion(&host->released);
1638
1639                 /*
1640                  * Mark all target ports as removed, so we stop queueing
1641                  * commands and don't try to reconnect.
1642                  */
1643                 down(&host->target_mutex);
1644                 list_for_each_entry_safe(target, tmp_target,
1645                                          &host->target_list, list) {
1646                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
1647                         if (target->state != SRP_TARGET_REMOVED)
1648                                 target->state = SRP_TARGET_REMOVED;
1649                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
1650                 }
1651                 up(&host->target_mutex);
1652
1653                 /*
1654                  * Wait for any reconnection tasks that may have
1655                  * started before we marked our target ports as
1656                  * removed, and any target port removal tasks.
1657                  */
1658                 flush_scheduled_work();
1659
1660                 list_for_each_entry_safe(target, tmp_target,
1661                                          &host->target_list, list) {
1662                         scsi_remove_host(target->scsi_host);
1663                         srp_disconnect_target(target);
1664                         ib_destroy_cm_id(target->cm_id);
1665                         srp_free_target_ib(target);
1666                         scsi_host_put(target->scsi_host);
1667                 }
1668
1669                 ib_dereg_mr(host->mr);
1670                 ib_dealloc_pd(host->pd);
1671                 kfree(host);
1672         }
1673
1674         kfree(dev_list);
1675 }
1676
1677 static int __init srp_init_module(void)
1678 {
1679         int ret;
1680
1681         ret = class_register(&srp_class);
1682         if (ret) {
1683                 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
1684                 return ret;
1685         }
1686
1687         ret = ib_register_client(&srp_client);
1688         if (ret) {
1689                 printk(KERN_ERR PFX "couldn't register IB client\n");
1690                 class_unregister(&srp_class);
1691                 return ret;
1692         }
1693
1694         return 0;
1695 }
1696
1697 static void __exit srp_cleanup_module(void)
1698 {
1699         ib_unregister_client(&srp_client);
1700         class_unregister(&srp_class);
1701 }
1702
1703 module_init(srp_init_module);
1704 module_exit(srp_cleanup_module);