drivers/infiniband/ulp/srpt/ib_srpt.c

   1 /*
   2  * Copyright (c) 2006 - 2009 Mellanox Technology Inc.  All rights reserved.
   3  * Copyright (C) 2008 - 2011 Bart Van Assche <bvanassche@acm.org>.
   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  */
  34
  35 #include <linux/module.h>
  36 #include <linux/init.h>
  37 #include <linux/slab.h>
  38 #include <linux/err.h>
  39 #include <linux/ctype.h>
  40 #include <linux/kthread.h>
  41 #include <linux/string.h>
  42 #include <linux/delay.h>
  43 #include <linux/atomic.h>
  44 #include <scsi/scsi_tcq.h>
  45 #include <target/configfs_macros.h>
  46 #include <target/target_core_base.h>
  47 #include <target/target_core_fabric_configfs.h>
  48 #include <target/target_core_fabric.h>
  49 #include <target/target_core_configfs.h>
  50 #include "ib_srpt.h"
  51
  52 /* Name of this kernel module. */
  53 #define DRV_NAME                "ib_srpt"
  54 #define DRV_VERSION             "2.0.0"
  55 #define DRV_RELDATE             "2011-02-14"
  56
  57 #define SRPT_ID_STRING  "Linux SRP target"
  58
  59 #undef pr_fmt
  60 #define pr_fmt(fmt) DRV_NAME " " fmt
  61
  62 MODULE_AUTHOR("Vu Pham and Bart Van Assche");
  63 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol target "
  64                    "v" DRV_VERSION " (" DRV_RELDATE ")");
  65 MODULE_LICENSE("Dual BSD/GPL");
  66
  67 /*
  68  * Global Variables
  69  */
  70
  71 static u64 srpt_service_guid;
  72 static DEFINE_SPINLOCK(srpt_dev_lock);  /* Protects srpt_dev_list. */
  73 static LIST_HEAD(srpt_dev_list);        /* List of srpt_device structures. */
  74
  75 static unsigned srp_max_req_size = DEFAULT_MAX_REQ_SIZE;
  76 module_param(srp_max_req_size, int, 0444);
  77 MODULE_PARM_DESC(srp_max_req_size,
  78                  "Maximum size of SRP request messages in bytes.");
  79
  80 static int srpt_srq_size = DEFAULT_SRPT_SRQ_SIZE;
  81 module_param(srpt_srq_size, int, 0444);
  82 MODULE_PARM_DESC(srpt_srq_size,
  83                  "Shared receive queue (SRQ) size.");
  84
  85 static int srpt_get_u64_x(char *buffer, struct kernel_param *kp)
  86 {
  87         return sprintf(buffer, "0x%016llx", *(u64 *)kp->arg);
  88 }
  89 module_param_call(srpt_service_guid, NULL, srpt_get_u64_x, &srpt_service_guid,
  90                   0444);
  91 MODULE_PARM_DESC(srpt_service_guid,
  92                  "Using this value for ioc_guid, id_ext, and cm_listen_id"
  93                  " instead of using the node_guid of the first HCA.");
  94
  95 static struct ib_client srpt_client;
  96 static struct target_fabric_configfs *srpt_target;
  97 static void srpt_release_channel(struct srpt_rdma_ch *ch);
  98 static int srpt_queue_status(struct se_cmd *cmd);
  99
 100 /**
 101  * opposite_dma_dir() - Swap DMA_TO_DEVICE and DMA_FROM_DEVICE.
 102  */
 103 static inline
 104 enum dma_data_direction opposite_dma_dir(enum dma_data_direction dir)
 105 {
 106         switch (dir) {
 107         case DMA_TO_DEVICE:     return DMA_FROM_DEVICE;
 108         case DMA_FROM_DEVICE:   return DMA_TO_DEVICE;
 109         default:                return dir;
 110         }
 111 }
 112
 113 /**
 114  * srpt_sdev_name() - Return the name associated with the HCA.
 115  *
 116  * Examples are ib0, ib1, ...
 117  */
 118 static inline const char *srpt_sdev_name(struct srpt_device *sdev)
 119 {
 120         return sdev->device->name;
 121 }
 122
 123 static enum rdma_ch_state srpt_get_ch_state(struct srpt_rdma_ch *ch)
 124 {
 125         unsigned long flags;
 126         enum rdma_ch_state state;
 127
 128         spin_lock_irqsave(&ch->spinlock, flags);
 129         state = ch->state;
 130         spin_unlock_irqrestore(&ch->spinlock, flags);
 131         return state;
 132 }
 133
 134 static enum rdma_ch_state
 135 srpt_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state new_state)
 136 {
 137         unsigned long flags;
 138         enum rdma_ch_state prev;
 139
 140         spin_lock_irqsave(&ch->spinlock, flags);
 141         prev = ch->state;
 142         ch->state = new_state;
 143         spin_unlock_irqrestore(&ch->spinlock, flags);
 144         return prev;
 145 }
 146
 147 /**
 148  * srpt_test_and_set_ch_state() - Test and set the channel state.
 149  *
 150  * Returns true if and only if the channel state has been set to the new state.
 151  */
 152 static bool
 153 srpt_test_and_set_ch_state(struct srpt_rdma_ch *ch, enum rdma_ch_state old,
 154                            enum rdma_ch_state new)
 155 {
 156         unsigned long flags;
 157         enum rdma_ch_state prev;
 158
 159         spin_lock_irqsave(&ch->spinlock, flags);
 160         prev = ch->state;
 161         if (prev == old)
 162                 ch->state = new;
 163         spin_unlock_irqrestore(&ch->spinlock, flags);
 164         return prev == old;
 165 }
 166
 167 /**
 168  * srpt_event_handler() - Asynchronous IB event callback function.
 169  *
 170  * Callback function called by the InfiniBand core when an asynchronous IB
 171  * event occurs. This callback may occur in interrupt context. See also
 172  * section 11.5.2, Set Asynchronous Event Handler in the InfiniBand
 173  * Architecture Specification.
 174  */
 175 static void srpt_event_handler(struct ib_event_handler *handler,
 176                                struct ib_event *event)
 177 {
 178         struct srpt_device *sdev;
 179         struct srpt_port *sport;
 180
 181         sdev = ib_get_client_data(event->device, &srpt_client);
 182         if (!sdev || sdev->device != event->device)
 183                 return;
 184
 185         pr_debug("ASYNC event= %d on device= %s\n", event->event,
 186                  srpt_sdev_name(sdev));
 187
 188         switch (event->event) {
 189         case IB_EVENT_PORT_ERR:
 190                 if (event->element.port_num <= sdev->device->phys_port_cnt) {
 191                         sport = &sdev->port[event->element.port_num - 1];
 192                         sport->lid = 0;
 193                         sport->sm_lid = 0;
 194                 }
 195                 break;
 196         case IB_EVENT_PORT_ACTIVE:
 197         case IB_EVENT_LID_CHANGE:
 198         case IB_EVENT_PKEY_CHANGE:
 199         case IB_EVENT_SM_CHANGE:
 200         case IB_EVENT_CLIENT_REREGISTER:
 201         case IB_EVENT_GID_CHANGE:
 202                 /* Refresh port data asynchronously. */
 203                 if (event->element.port_num <= sdev->device->phys_port_cnt) {
 204                         sport = &sdev->port[event->element.port_num - 1];
 205                         if (!sport->lid && !sport->sm_lid)
 206                                 schedule_work(&sport->work);
 207                 }
 208                 break;
 209         default:
 210                 printk(KERN_ERR "received unrecognized IB event %d\n",
 211                        event->event);
 212                 break;
 213         }
 214 }
 215
 216 /**
 217  * srpt_srq_event() - SRQ event callback function.
 218  */
 219 static void srpt_srq_event(struct ib_event *event, void *ctx)
 220 {
 221         printk(KERN_INFO "SRQ event %d\n", event->event);
 222 }
 223
 224 /**
 225  * srpt_qp_event() - QP event callback function.
 226  */
 227 static void srpt_qp_event(struct ib_event *event, struct srpt_rdma_ch *ch)
 228 {
 229         pr_debug("QP event %d on cm_id=%p sess_name=%s state=%d\n",
 230                  event->event, ch->cm_id, ch->sess_name, srpt_get_ch_state(ch));
 231
 232         switch (event->event) {
 233         case IB_EVENT_COMM_EST:
 234                 ib_cm_notify(ch->cm_id, event->event);
 235                 break;
 236         case IB_EVENT_QP_LAST_WQE_REACHED:
 237                 if (srpt_test_and_set_ch_state(ch, CH_DRAINING,
 238                                                CH_RELEASING))
 239                         srpt_release_channel(ch);
 240                 else
 241                         pr_debug("%s: state %d - ignored LAST_WQE.\n",
 242                                  ch->sess_name, srpt_get_ch_state(ch));
 243                 break;
 244         default:
 245                 printk(KERN_ERR "received unrecognized IB QP event %d\n",
 246                        event->event);
 247                 break;
 248         }
 249 }
 250
 251 /**
 252  * srpt_set_ioc() - Helper function for initializing an IOUnitInfo structure.
 253  *
 254  * @slot: one-based slot number.
 255  * @value: four-bit value.
 256  *
 257  * Copies the lowest four bits of value in element slot of the array of four
 258  * bit elements called c_list (controller list). The index slot is one-based.
 259  */
 260 static void srpt_set_ioc(u8 *c_list, u32 slot, u8 value)
 261 {
 262         u16 id;
 263         u8 tmp;
 264
 265         id = (slot - 1) / 2;
 266         if (slot & 0x1) {
 267                 tmp = c_list[id] & 0xf;
 268                 c_list[id] = (value << 4) | tmp;
 269         } else {
 270                 tmp = c_list[id] & 0xf0;
 271                 c_list[id] = (value & 0xf) | tmp;
 272         }
 273 }
 274
 275 /**
 276  * srpt_get_class_port_info() - Copy ClassPortInfo to a management datagram.
 277  *
 278  * See also section 16.3.3.1 ClassPortInfo in the InfiniBand Architecture
 279  * Specification.
 280  */
 281 static void srpt_get_class_port_info(struct ib_dm_mad *mad)
 282 {
 283         struct ib_class_port_info *cif;
 284
 285         cif = (struct ib_class_port_info *)mad->data;
 286         memset(cif, 0, sizeof *cif);
 287         cif->base_version = 1;
 288         cif->class_version = 1;
 289         cif->resp_time_value = 20;
 290
 291         mad->mad_hdr.status = 0;
 292 }
 293
 294 /**
 295  * srpt_get_iou() - Write IOUnitInfo to a management datagram.
 296  *
 297  * See also section 16.3.3.3 IOUnitInfo in the InfiniBand Architecture
 298  * Specification. See also section B.7, table B.6 in the SRP r16a document.
 299  */
 300 static void srpt_get_iou(struct ib_dm_mad *mad)
 301 {
 302         struct ib_dm_iou_info *ioui;
 303         u8 slot;
 304         int i;
 305
 306         ioui = (struct ib_dm_iou_info *)mad->data;
 307         ioui->change_id = __constant_cpu_to_be16(1);
 308         ioui->max_controllers = 16;
 309
 310         /* set present for slot 1 and empty for the rest */
 311         srpt_set_ioc(ioui->controller_list, 1, 1);
 312         for (i = 1, slot = 2; i < 16; i++, slot++)
 313                 srpt_set_ioc(ioui->controller_list, slot, 0);
 314
 315         mad->mad_hdr.status = 0;
 316 }
 317
 318 /**
 319  * srpt_get_ioc() - Write IOControllerprofile to a management datagram.
 320  *
 321  * See also section 16.3.3.4 IOControllerProfile in the InfiniBand
 322  * Architecture Specification. See also section B.7, table B.7 in the SRP
 323  * r16a document.
 324  */
 325 static void srpt_get_ioc(struct srpt_port *sport, u32 slot,
 326                          struct ib_dm_mad *mad)
 327 {
 328         struct srpt_device *sdev = sport->sdev;
 329         struct ib_dm_ioc_profile *iocp;
 330
 331         iocp = (struct ib_dm_ioc_profile *)mad->data;
 332
 333         if (!slot || slot > 16) {
 334                 mad->mad_hdr.status
 335                         = __constant_cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);
 336                 return;
 337         }
 338
 339         if (slot > 2) {
 340                 mad->mad_hdr.status
 341                         = __constant_cpu_to_be16(DM_MAD_STATUS_NO_IOC);
 342                 return;
 343         }
 344
 345         memset(iocp, 0, sizeof *iocp);
 346         strcpy(iocp->id_string, SRPT_ID_STRING);
 347         iocp->guid = cpu_to_be64(srpt_service_guid);
 348         iocp->vendor_id = cpu_to_be32(sdev->dev_attr.vendor_id);
 349         iocp->device_id = cpu_to_be32(sdev->dev_attr.vendor_part_id);
 350         iocp->device_version = cpu_to_be16(sdev->dev_attr.hw_ver);
 351         iocp->subsys_vendor_id = cpu_to_be32(sdev->dev_attr.vendor_id);
 352         iocp->subsys_device_id = 0x0;
 353         iocp->io_class = __constant_cpu_to_be16(SRP_REV16A_IB_IO_CLASS);
 354         iocp->io_subclass = __constant_cpu_to_be16(SRP_IO_SUBCLASS);
 355         iocp->protocol = __constant_cpu_to_be16(SRP_PROTOCOL);
 356         iocp->protocol_version = __constant_cpu_to_be16(SRP_PROTOCOL_VERSION);
 357         iocp->send_queue_depth = cpu_to_be16(sdev->srq_size);
 358         iocp->rdma_read_depth = 4;
 359         iocp->send_size = cpu_to_be32(srp_max_req_size);
 360         iocp->rdma_size = cpu_to_be32(min(sport->port_attrib.srp_max_rdma_size,
 361                                           1U << 24));
 362         iocp->num_svc_entries = 1;
 363         iocp->op_cap_mask = SRP_SEND_TO_IOC | SRP_SEND_FROM_IOC |
 364                 SRP_RDMA_READ_FROM_IOC | SRP_RDMA_WRITE_FROM_IOC;
 365
 366         mad->mad_hdr.status = 0;
 367 }
 368
 369 /**
 370  * srpt_get_svc_entries() - Write ServiceEntries to a management datagram.
 371  *
 372  * See also section 16.3.3.5 ServiceEntries in the InfiniBand Architecture
 373  * Specification. See also section B.7, table B.8 in the SRP r16a document.
 374  */
 375 static void srpt_get_svc_entries(u64 ioc_guid,
 376                                  u16 slot, u8 hi, u8 lo, struct ib_dm_mad *mad)
 377 {
 378         struct ib_dm_svc_entries *svc_entries;
 379
 380         WARN_ON(!ioc_guid);
 381
 382         if (!slot || slot > 16) {
 383                 mad->mad_hdr.status
 384                         = __constant_cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);
 385                 return;
 386         }
 387
 388         if (slot > 2 || lo > hi || hi > 1) {
 389                 mad->mad_hdr.status
 390                         = __constant_cpu_to_be16(DM_MAD_STATUS_NO_IOC);
 391                 return;
 392         }
 393
 394         svc_entries = (struct ib_dm_svc_entries *)mad->data;
 395         memset(svc_entries, 0, sizeof *svc_entries);
 396         svc_entries->service_entries[0].id = cpu_to_be64(ioc_guid);
 397         snprintf(svc_entries->service_entries[0].name,
 398                  sizeof(svc_entries->service_entries[0].name),
 399                  "%s%016llx",
 400                  SRP_SERVICE_NAME_PREFIX,
 401                  ioc_guid);
 402
 403         mad->mad_hdr.status = 0;
 404 }
 405
 406 /**
 407  * srpt_mgmt_method_get() - Process a received management datagram.
 408  * @sp:      source port through which the MAD has been received.
 409  * @rq_mad:  received MAD.
 410  * @rsp_mad: response MAD.
 411  */
 412 static void srpt_mgmt_method_get(struct srpt_port *sp, struct ib_mad *rq_mad,
 413                                  struct ib_dm_mad *rsp_mad)
 414 {
 415         u16 attr_id;
 416         u32 slot;
 417         u8 hi, lo;
 418
 419         attr_id = be16_to_cpu(rq_mad->mad_hdr.attr_id);
 420         switch (attr_id) {
 421         case DM_ATTR_CLASS_PORT_INFO:
 422                 srpt_get_class_port_info(rsp_mad);
 423                 break;
 424         case DM_ATTR_IOU_INFO:
 425                 srpt_get_iou(rsp_mad);
 426                 break;
 427         case DM_ATTR_IOC_PROFILE:
 428                 slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);
 429                 srpt_get_ioc(sp, slot, rsp_mad);
 430                 break;
 431         case DM_ATTR_SVC_ENTRIES:
 432                 slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);
 433                 hi = (u8) ((slot >> 8) & 0xff);
 434                 lo = (u8) (slot & 0xff);
 435                 slot = (u16) ((slot >> 16) & 0xffff);
 436                 srpt_get_svc_entries(srpt_service_guid,
 437                                      slot, hi, lo, rsp_mad);
 438                 break;
 439         default:
 440                 rsp_mad->mad_hdr.status =
 441                     __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);
 442                 break;
 443         }
 444 }
 445
 446 /**
 447  * srpt_mad_send_handler() - Post MAD-send callback function.
 448  */
 449 static void srpt_mad_send_handler(struct ib_mad_agent *mad_agent,
 450                                   struct ib_mad_send_wc *mad_wc)
 451 {
 452         ib_destroy_ah(mad_wc->send_buf->ah);
 453         ib_free_send_mad(mad_wc->send_buf);
 454 }
 455
 456 /**
 457  * srpt_mad_recv_handler() - MAD reception callback function.
 458  */
 459 static void srpt_mad_recv_handler(struct ib_mad_agent *mad_agent,
 460                                   struct ib_mad_recv_wc *mad_wc)
 461 {
 462         struct srpt_port *sport = (struct srpt_port *)mad_agent->context;
 463         struct ib_ah *ah;
 464         struct ib_mad_send_buf *rsp;
 465         struct ib_dm_mad *dm_mad;
 466
 467         if (!mad_wc || !mad_wc->recv_buf.mad)
 468                 return;
 469
 470         ah = ib_create_ah_from_wc(mad_agent->qp->pd, mad_wc->wc,
 471                                   mad_wc->recv_buf.grh, mad_agent->port_num);
 472         if (IS_ERR(ah))
 473                 goto err;
 474
 475         BUILD_BUG_ON(offsetof(struct ib_dm_mad, data) != IB_MGMT_DEVICE_HDR);
 476
 477         rsp = ib_create_send_mad(mad_agent, mad_wc->wc->src_qp,
 478                                  mad_wc->wc->pkey_index, 0,
 479                                  IB_MGMT_DEVICE_HDR, IB_MGMT_DEVICE_DATA,
 480                                  GFP_KERNEL);
 481         if (IS_ERR(rsp))
 482                 goto err_rsp;
 483
 484         rsp->ah = ah;
 485
 486         dm_mad = rsp->mad;
 487         memcpy(dm_mad, mad_wc->recv_buf.mad, sizeof *dm_mad);
 488         dm_mad->mad_hdr.method = IB_MGMT_METHOD_GET_RESP;
 489         dm_mad->mad_hdr.status = 0;
 490
 491         switch (mad_wc->recv_buf.mad->mad_hdr.method) {
 492         case IB_MGMT_METHOD_GET:
 493                 srpt_mgmt_method_get(sport, mad_wc->recv_buf.mad, dm_mad);
 494                 break;
 495         case IB_MGMT_METHOD_SET:
 496                 dm_mad->mad_hdr.status =
 497                     __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);
 498                 break;
 499         default:
 500                 dm_mad->mad_hdr.status =
 501                     __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD);
 502                 break;
 503         }
 504
 505         if (!ib_post_send_mad(rsp, NULL)) {
 506                 ib_free_recv_mad(mad_wc);
 507                 /* will destroy_ah & free_send_mad in send completion */
 508                 return;
 509         }
 510
 511         ib_free_send_mad(rsp);
 512
 513 err_rsp:
 514         ib_destroy_ah(ah);
 515 err:
 516         ib_free_recv_mad(mad_wc);
 517 }
 518
 519 /**
 520  * srpt_refresh_port() - Configure a HCA port.
 521  *
 522  * Enable InfiniBand management datagram processing, update the cached sm_lid,
 523  * lid and gid values, and register a callback function for processing MADs
 524  * on the specified port.
 525  *
 526  * Note: It is safe to call this function more than once for the same port.
 527  */
 528 static int srpt_refresh_port(struct srpt_port *sport)
 529 {
 530         struct ib_mad_reg_req reg_req;
 531         struct ib_port_modify port_modify;
 532         struct ib_port_attr port_attr;
 533         int ret;
 534
 535         memset(&port_modify, 0, sizeof port_modify);
 536         port_modify.set_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;
 537         port_modify.clr_port_cap_mask = 0;
 538
 539         ret = ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify);
 540         if (ret)
 541                 goto err_mod_port;
 542
 543         ret = ib_query_port(sport->sdev->device, sport->port, &port_attr);
 544         if (ret)
 545                 goto err_query_port;
 546
 547         sport->sm_lid = port_attr.sm_lid;
 548         sport->lid = port_attr.lid;
 549
 550         ret = ib_query_gid(sport->sdev->device, sport->port, 0, &sport->gid);
 551         if (ret)
 552                 goto err_query_port;
 553
 554         if (!sport->mad_agent) {
 555                 memset(&reg_req, 0, sizeof reg_req);
 556                 reg_req.mgmt_class = IB_MGMT_CLASS_DEVICE_MGMT;
 557                 reg_req.mgmt_class_version = IB_MGMT_BASE_VERSION;
 558                 set_bit(IB_MGMT_METHOD_GET, reg_req.method_mask);
 559                 set_bit(IB_MGMT_METHOD_SET, reg_req.method_mask);
 560
 561                 sport->mad_agent = ib_register_mad_agent(sport->sdev->device,
 562                                                          sport->port,
 563                                                          IB_QPT_GSI,
 564                                                          &reg_req, 0,
 565                                                          srpt_mad_send_handler,
 566                                                          srpt_mad_recv_handler,
 567                                                          sport, 0);
 568                 if (IS_ERR(sport->mad_agent)) {
 569                         ret = PTR_ERR(sport->mad_agent);
 570                         sport->mad_agent = NULL;
 571                         goto err_query_port;
 572                 }
 573         }
 574
 575         return 0;
 576
 577 err_query_port:
 578
 579         port_modify.set_port_cap_mask = 0;
 580         port_modify.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;
 581         ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify);
 582
 583 err_mod_port:
 584
 585         return ret;
 586 }
 587
 588 /**
 589  * srpt_unregister_mad_agent() - Unregister MAD callback functions.
 590  *
 591  * Note: It is safe to call this function more than once for the same device.
 592  */
 593 static void srpt_unregister_mad_agent(struct srpt_device *sdev)
 594 {
 595         struct ib_port_modify port_modify = {
 596                 .clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP,
 597         };
 598         struct srpt_port *sport;
 599         int i;
 600
 601         for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
 602                 sport = &sdev->port[i - 1];
 603                 WARN_ON(sport->port != i);
 604                 if (ib_modify_port(sdev->device, i, 0, &port_modify) < 0)
 605                         printk(KERN_ERR "disabling MAD processing failed.\n");
 606                 if (sport->mad_agent) {
 607                         ib_unregister_mad_agent(sport->mad_agent);
 608                         sport->mad_agent = NULL;
 609                 }
 610         }
 611 }
 612
 613 /**
 614  * srpt_alloc_ioctx() - Allocate an SRPT I/O context structure.
 615  */
 616 static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev,
 617                                            int ioctx_size, int dma_size,
 618                                            enum dma_data_direction dir)
 619 {
 620         struct srpt_ioctx *ioctx;
 621
 622         ioctx = kmalloc(ioctx_size, GFP_KERNEL);
 623         if (!ioctx)
 624                 goto err;
 625
 626         ioctx->buf = kmalloc(dma_size, GFP_KERNEL);
 627         if (!ioctx->buf)
 628                 goto err_free_ioctx;
 629
 630         ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf, dma_size, dir);
 631         if (ib_dma_mapping_error(sdev->device, ioctx->dma))
 632                 goto err_free_buf;
 633
 634         return ioctx;
 635
 636 err_free_buf:
 637         kfree(ioctx->buf);
 638 err_free_ioctx:
 639         kfree(ioctx);
 640 err:
 641         return NULL;
 642 }
 643
 644 /**
 645  * srpt_free_ioctx() - Free an SRPT I/O context structure.
 646  */
 647 static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx,
 648                             int dma_size, enum dma_data_direction dir)
 649 {
 650         if (!ioctx)
 651                 return;
 652
 653         ib_dma_unmap_single(sdev->device, ioctx->dma, dma_size, dir);
 654         kfree(ioctx->buf);
 655         kfree(ioctx);
 656 }
 657
 658 /**
 659  * srpt_alloc_ioctx_ring() - Allocate a ring of SRPT I/O context structures.
 660  * @sdev:       Device to allocate the I/O context ring for.
 661  * @ring_size:  Number of elements in the I/O context ring.
 662  * @ioctx_size: I/O context size.
 663  * @dma_size:   DMA buffer size.
 664  * @dir:        DMA data direction.
 665  */
 666 static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev,
 667                                 int ring_size, int ioctx_size,
 668                                 int dma_size, enum dma_data_direction dir)
 669 {
 670         struct srpt_ioctx **ring;
 671         int i;
 672
 673         WARN_ON(ioctx_size != sizeof(struct srpt_recv_ioctx)
 674                 && ioctx_size != sizeof(struct srpt_send_ioctx));
 675
 676         ring = kmalloc(ring_size * sizeof(ring[0]), GFP_KERNEL);
 677         if (!ring)
 678                 goto out;
 679         for (i = 0; i < ring_size; ++i) {
 680                 ring[i] = srpt_alloc_ioctx(sdev, ioctx_size, dma_size, dir);
 681                 if (!ring[i])
 682                         goto err;
 683                 ring[i]->index = i;
 684         }
 685         goto out;
 686
 687 err:
 688         while (--i >= 0)
 689                 srpt_free_ioctx(sdev, ring[i], dma_size, dir);
 690         kfree(ring);
 691         ring = NULL;
 692 out:
 693         return ring;
 694 }
 695
 696 /**
 697  * srpt_free_ioctx_ring() - Free the ring of SRPT I/O context structures.
 698  */
 699 static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring,
 700                                  struct srpt_device *sdev, int ring_size,
 701                                  int dma_size, enum dma_data_direction dir)
 702 {
 703         int i;
 704
 705         for (i = 0; i < ring_size; ++i)
 706                 srpt_free_ioctx(sdev, ioctx_ring[i], dma_size, dir);
 707         kfree(ioctx_ring);
 708 }
 709
 710 /**
 711  * srpt_get_cmd_state() - Get the state of a SCSI command.
 712  */
 713 static enum srpt_command_state srpt_get_cmd_state(struct srpt_send_ioctx *ioctx)
 714 {
 715         enum srpt_command_state state;
 716         unsigned long flags;
 717
 718         BUG_ON(!ioctx);
 719
 720         spin_lock_irqsave(&ioctx->spinlock, flags);
 721         state = ioctx->state;
 722         spin_unlock_irqrestore(&ioctx->spinlock, flags);
 723         return state;
 724 }
 725
 726 /**
 727  * srpt_set_cmd_state() - Set the state of a SCSI command.
 728  *
 729  * Does not modify the state of aborted commands. Returns the previous command
 730  * state.
 731  */
 732 static enum srpt_command_state srpt_set_cmd_state(struct srpt_send_ioctx *ioctx,
 733                                                   enum srpt_command_state new)
 734 {
 735         enum srpt_command_state previous;
 736         unsigned long flags;
 737
 738         BUG_ON(!ioctx);
 739
 740         spin_lock_irqsave(&ioctx->spinlock, flags);
 741         previous = ioctx->state;
 742         if (previous != SRPT_STATE_DONE)
 743                 ioctx->state = new;
 744         spin_unlock_irqrestore(&ioctx->spinlock, flags);
 745
 746         return previous;
 747 }
 748
 749 /**
 750  * srpt_test_and_set_cmd_state() - Test and set the state of a command.
 751  *
 752  * Returns true if and only if the previous command state was equal to 'old'.
 753  */
 754 static bool srpt_test_and_set_cmd_state(struct srpt_send_ioctx *ioctx,
 755                                         enum srpt_command_state old,
 756                                         enum srpt_command_state new)
 757 {
 758         enum srpt_command_state previous;
 759         unsigned long flags;
 760
 761         WARN_ON(!ioctx);
 762         WARN_ON(old == SRPT_STATE_DONE);
 763         WARN_ON(new == SRPT_STATE_NEW);
 764
 765         spin_lock_irqsave(&ioctx->spinlock, flags);
 766         previous = ioctx->state;
 767         if (previous == old)
 768                 ioctx->state = new;
 769         spin_unlock_irqrestore(&ioctx->spinlock, flags);
 770         return previous == old;
 771 }
 772
 773 /**
 774  * srpt_post_recv() - Post an IB receive request.
 775  */
 776 static int srpt_post_recv(struct srpt_device *sdev,
 777                           struct srpt_recv_ioctx *ioctx)
 778 {
 779         struct ib_sge list;
 780         struct ib_recv_wr wr, *bad_wr;
 781
 782         BUG_ON(!sdev);
 783         wr.wr_id = encode_wr_id(SRPT_RECV, ioctx->ioctx.index);
 784
 785         list.addr = ioctx->ioctx.dma;
 786         list.length = srp_max_req_size;
 787         list.lkey = sdev->mr->lkey;
 788
 789         wr.next = NULL;
 790         wr.sg_list = &list;
 791         wr.num_sge = 1;
 792
 793         return ib_post_srq_recv(sdev->srq, &wr, &bad_wr);
 794 }
 795
 796 /**
 797  * srpt_post_send() - Post an IB send request.
 798  *
 799  * Returns zero upon success and a non-zero value upon failure.
 800  */
 801 static int srpt_post_send(struct srpt_rdma_ch *ch,
 802                           struct srpt_send_ioctx *ioctx, int len)
 803 {
 804         struct ib_sge list;
 805         struct ib_send_wr wr, *bad_wr;
 806         struct srpt_device *sdev = ch->sport->sdev;
 807         int ret;
 808
 809         atomic_inc(&ch->req_lim);
 810
 811         ret = -ENOMEM;
 812         if (unlikely(atomic_dec_return(&ch->sq_wr_avail) < 0)) {
 813                 printk(KERN_WARNING "IB send queue full (needed 1)\n");
 814                 goto out;
 815         }
 816
 817         ib_dma_sync_single_for_device(sdev->device, ioctx->ioctx.dma, len,
 818                                       DMA_TO_DEVICE);
 819
 820         list.addr = ioctx->ioctx.dma;
 821         list.length = len;
 822         list.lkey = sdev->mr->lkey;
 823
 824         wr.next = NULL;
 825         wr.wr_id = encode_wr_id(SRPT_SEND, ioctx->ioctx.index);
 826         wr.sg_list = &list;
 827         wr.num_sge = 1;
 828         wr.opcode = IB_WR_SEND;
 829         wr.send_flags = IB_SEND_SIGNALED;
 830
 831         ret = ib_post_send(ch->qp, &wr, &bad_wr);
 832
 833 out:
 834         if (ret < 0) {
 835                 atomic_inc(&ch->sq_wr_avail);
 836                 atomic_dec(&ch->req_lim);
 837         }
 838         return ret;
 839 }
 840
 841 /**
 842  * srpt_get_desc_tbl() - Parse the data descriptors of an SRP_CMD request.
 843  * @ioctx: Pointer to the I/O context associated with the request.
 844  * @srp_cmd: Pointer to the SRP_CMD request data.
 845  * @dir: Pointer to the variable to which the transfer direction will be
 846  *   written.
 847  * @data_len: Pointer to the variable to which the total data length of all
 848  *   descriptors in the SRP_CMD request will be written.
 849  *
 850  * This function initializes ioctx->nrbuf and ioctx->r_bufs.
 851  *
 852  * Returns -EINVAL when the SRP_CMD request contains inconsistent descriptors;
 853  * -ENOMEM when memory allocation fails and zero upon success.
 854  */
 855 static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
 856                              struct srp_cmd *srp_cmd,
 857                              enum dma_data_direction *dir, u64 *data_len)
 858 {
 859         struct srp_indirect_buf *idb;
 860         struct srp_direct_buf *db;
 861         unsigned add_cdb_offset;
 862         int ret;
 863
 864         /*
 865          * The pointer computations below will only be compiled correctly
 866          * if srp_cmd::add_data is declared as s8*, u8*, s8[] or u8[], so check
 867          * whether srp_cmd::add_data has been declared as a byte pointer.
 868          */
 869         BUILD_BUG_ON(!__same_type(srp_cmd->add_data[0], (s8)0)
 870                      && !__same_type(srp_cmd->add_data[0], (u8)0));
 871
 872         BUG_ON(!dir);
 873         BUG_ON(!data_len);
 874
 875         ret = 0;
 876         *data_len = 0;
 877
 878         /*
 879          * The lower four bits of the buffer format field contain the DATA-IN
 880          * buffer descriptor format, and the highest four bits contain the
 881          * DATA-OUT buffer descriptor format.
 882          */
 883         *dir = DMA_NONE;
 884         if (srp_cmd->buf_fmt & 0xf)
 885                 /* DATA-IN: transfer data from target to initiator (read). */
 886                 *dir = DMA_FROM_DEVICE;
 887         else if (srp_cmd->buf_fmt >> 4)
 888                 /* DATA-OUT: transfer data from initiator to target (write). */
 889                 *dir = DMA_TO_DEVICE;
 890
 891         /*
 892          * According to the SRP spec, the lower two bits of the 'ADDITIONAL
 893          * CDB LENGTH' field are reserved and the size in bytes of this field
 894          * is four times the value specified in bits 3..7. Hence the "& ~3".
 895          */
 896         add_cdb_offset = srp_cmd->add_cdb_len & ~3;
 897         if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) ||
 898             ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) {
 899                 ioctx->n_rbuf = 1;
 900                 ioctx->rbufs = &ioctx->single_rbuf;
 901
 902                 db = (struct srp_direct_buf *)(srp_cmd->add_data
 903                                                + add_cdb_offset);
 904                 memcpy(ioctx->rbufs, db, sizeof *db);
 905                 *data_len = be32_to_cpu(db->len);
 906         } else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) ||
 907                    ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) {
 908                 idb = (struct srp_indirect_buf *)(srp_cmd->add_data
 909                                                   + add_cdb_offset);
 910
 911                 ioctx->n_rbuf = be32_to_cpu(idb->table_desc.len) / sizeof *db;
 912
 913                 if (ioctx->n_rbuf >
 914                     (srp_cmd->data_out_desc_cnt + srp_cmd->data_in_desc_cnt)) {
 915                         printk(KERN_ERR "received unsupported SRP_CMD request"
 916                                " type (%u out + %u in != %u / %zu)\n",
 917                                srp_cmd->data_out_desc_cnt,
 918                                srp_cmd->data_in_desc_cnt,
 919                                be32_to_cpu(idb->table_desc.len),
 920                                sizeof(*db));
 921                         ioctx->n_rbuf = 0;
 922                         ret = -EINVAL;
 923                         goto out;
 924                 }
 925
 926                 if (ioctx->n_rbuf == 1)
 927                         ioctx->rbufs = &ioctx->single_rbuf;
 928                 else {
 929                         ioctx->rbufs =
 930                                 kmalloc(ioctx->n_rbuf * sizeof *db, GFP_ATOMIC);
 931                         if (!ioctx->rbufs) {
 932                                 ioctx->n_rbuf = 0;
 933                                 ret = -ENOMEM;
 934                                 goto out;
 935                         }
 936                 }
 937
 938                 db = idb->desc_list;
 939                 memcpy(ioctx->rbufs, db, ioctx->n_rbuf * sizeof *db);
 940                 *data_len = be32_to_cpu(idb->len);
 941         }
 942 out:
 943         return ret;
 944 }
 945
 946 /**
 947  * srpt_init_ch_qp() - Initialize queue pair attributes.
 948  *
 949  * Initialized the attributes of queue pair 'qp' by allowing local write,
 950  * remote read and remote write. Also transitions 'qp' to state IB_QPS_INIT.
 951  */
 952 static int srpt_init_ch_qp(struct srpt_rdma_ch *ch, struct ib_qp *qp)
 953 {
 954         struct ib_qp_attr *attr;
 955         int ret;
 956
 957         attr = kzalloc(sizeof *attr, GFP_KERNEL);
 958         if (!attr)
 959                 return -ENOMEM;
 960
 961         attr->qp_state = IB_QPS_INIT;
 962         attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_READ |
 963             IB_ACCESS_REMOTE_WRITE;
 964         attr->port_num = ch->sport->port;
 965         attr->pkey_index = 0;
 966
 967         ret = ib_modify_qp(qp, attr,
 968                            IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PORT |
 969                            IB_QP_PKEY_INDEX);
 970
 971         kfree(attr);
 972         return ret;
 973 }
 974
 975 /**
 976  * srpt_ch_qp_rtr() - Change the state of a channel to 'ready to receive' (RTR).
 977  * @ch: channel of the queue pair.
 978  * @qp: queue pair to change the state of.
 979  *
 980  * Returns zero upon success and a negative value upon failure.
 981  *
 982  * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system.
 983  * If this structure ever becomes larger, it might be necessary to allocate
 984  * it dynamically instead of on the stack.
 985  */
 986 static int srpt_ch_qp_rtr(struct srpt_rdma_ch *ch, struct ib_qp *qp)
 987 {
 988         struct ib_qp_attr qp_attr;
 989         int attr_mask;
 990         int ret;
 991
 992         qp_attr.qp_state = IB_QPS_RTR;
 993         ret = ib_cm_init_qp_attr(ch->cm_id, &qp_attr, &attr_mask);
 994         if (ret)
 995                 goto out;
 996
 997         qp_attr.max_dest_rd_atomic = 4;
 998
 999         ret = ib_modify_qp(qp, &qp_attr, attr_mask);
1000
1001 out:
1002         return ret;
1003 }
1004
1005 /**
1006  * srpt_ch_qp_rts() - Change the state of a channel to 'ready to send' (RTS).
1007  * @ch: channel of the queue pair.
1008  * @qp: queue pair to change the state of.
1009  *
1010  * Returns zero upon success and a negative value upon failure.
1011  *
1012  * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system.
1013  * If this structure ever becomes larger, it might be necessary to allocate
1014  * it dynamically instead of on the stack.
1015  */
1016 static int srpt_ch_qp_rts(struct srpt_rdma_ch *ch, struct ib_qp *qp)
1017 {
1018         struct ib_qp_attr qp_attr;
1019         int attr_mask;
1020         int ret;
1021
1022         qp_attr.qp_state = IB_QPS_RTS;
1023         ret = ib_cm_init_qp_attr(ch->cm_id, &qp_attr, &attr_mask);
1024         if (ret)
1025                 goto out;
1026
1027         qp_attr.max_rd_atomic = 4;
1028
1029         ret = ib_modify_qp(qp, &qp_attr, attr_mask);
1030
1031 out:
1032         return ret;
1033 }
1034
1035 /**
1036  * srpt_ch_qp_err() - Set the channel queue pair state to 'error'.
1037  */
1038 static int srpt_ch_qp_err(struct srpt_rdma_ch *ch)
1039 {
1040         struct ib_qp_attr qp_attr;
1041
1042         qp_attr.qp_state = IB_QPS_ERR;
1043         return ib_modify_qp(ch->qp, &qp_attr, IB_QP_STATE);
1044 }
1045
1046 /**
1047  * srpt_unmap_sg_to_ib_sge() - Unmap an IB SGE list.
1048  */
1049 static void srpt_unmap_sg_to_ib_sge(struct srpt_rdma_ch *ch,
1050                                     struct srpt_send_ioctx *ioctx)
1051 {
1052         struct scatterlist *sg;
1053         enum dma_data_direction dir;
1054
1055         BUG_ON(!ch);
1056         BUG_ON(!ioctx);
1057         BUG_ON(ioctx->n_rdma && !ioctx->rdma_ius);
1058
1059         while (ioctx->n_rdma)
1060                 kfree(ioctx->rdma_ius[--ioctx->n_rdma].sge);
1061
1062         kfree(ioctx->rdma_ius);
1063         ioctx->rdma_ius = NULL;
1064
1065         if (ioctx->mapped_sg_count) {
1066                 sg = ioctx->sg;
1067                 WARN_ON(!sg);
1068                 dir = ioctx->cmd.data_direction;
1069                 BUG_ON(dir == DMA_NONE);
1070                 ib_dma_unmap_sg(ch->sport->sdev->device, sg, ioctx->sg_cnt,
1071                                 opposite_dma_dir(dir));
1072                 ioctx->mapped_sg_count = 0;
1073         }
1074 }
1075
1076 /**
1077  * srpt_map_sg_to_ib_sge() - Map an SG list to an IB SGE list.
1078  */
1079 static int srpt_map_sg_to_ib_sge(struct srpt_rdma_ch *ch,
1080                                  struct srpt_send_ioctx *ioctx)
1081 {
1082         struct ib_device *dev = ch->sport->sdev->device;
1083         struct se_cmd *cmd;
1084         struct scatterlist *sg, *sg_orig;
1085         int sg_cnt;
1086         enum dma_data_direction dir;
1087         struct rdma_iu *riu;
1088         struct srp_direct_buf *db;
1089         dma_addr_t dma_addr;
1090         struct ib_sge *sge;
1091         u64 raddr;
1092         u32 rsize;
1093         u32 tsize;
1094         u32 dma_len;
1095         int count, nrdma;
1096         int i, j, k;
1097
1098         BUG_ON(!ch);
1099         BUG_ON(!ioctx);
1100         cmd = &ioctx->cmd;
1101         dir = cmd->data_direction;
1102         BUG_ON(dir == DMA_NONE);
1103
1104         ioctx->sg = sg = sg_orig = cmd->t_data_sg;
1105         ioctx->sg_cnt = sg_cnt = cmd->t_data_nents;
1106
1107         count = ib_dma_map_sg(ch->sport->sdev->device, sg, sg_cnt,
1108                               opposite_dma_dir(dir));
1109         if (unlikely(!count))
1110                 return -EAGAIN;
1111
1112         ioctx->mapped_sg_count = count;
1113
1114         if (ioctx->rdma_ius && ioctx->n_rdma_ius)
1115                 nrdma = ioctx->n_rdma_ius;
1116         else {
1117                 nrdma = (count + SRPT_DEF_SG_PER_WQE - 1) / SRPT_DEF_SG_PER_WQE
1118                         + ioctx->n_rbuf;
1119
1120                 ioctx->rdma_ius = kzalloc(nrdma * sizeof *riu, GFP_KERNEL);
1121                 if (!ioctx->rdma_ius)
1122                         goto free_mem;
1123
1124                 ioctx->n_rdma_ius = nrdma;
1125         }
1126
1127         db = ioctx->rbufs;
1128         tsize = cmd->data_length;
1129         dma_len = ib_sg_dma_len(dev, &sg[0]);
1130         riu = ioctx->rdma_ius;
1131
1132         /*
1133          * For each remote desc - calculate the #ib_sge.
1134          * If #ib_sge < SRPT_DEF_SG_PER_WQE per rdma operation then
1135          *      each remote desc rdma_iu is required a rdma wr;
1136          * else
1137          *      we need to allocate extra rdma_iu to carry extra #ib_sge in
1138          *      another rdma wr
1139          */
1140         for (i = 0, j = 0;
1141              j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) {
1142                 rsize = be32_to_cpu(db->len);
1143                 raddr = be64_to_cpu(db->va);
1144                 riu->raddr = raddr;
1145                 riu->rkey = be32_to_cpu(db->key);
1146                 riu->sge_cnt = 0;
1147
1148                 /* calculate how many sge required for this remote_buf */
1149                 while (rsize > 0 && tsize > 0) {
1150
1151                         if (rsize >= dma_len) {
1152                                 tsize -= dma_len;
1153                                 rsize -= dma_len;
1154                                 raddr += dma_len;
1155
1156                                 if (tsize > 0) {
1157                                         ++j;
1158                                         if (j < count) {
1159                                                 sg = sg_next(sg);
1160                                                 dma_len = ib_sg_dma_len(
1161                                                                 dev, sg);
1162                                         }
1163                                 }
1164                         } else {
1165                                 tsize -= rsize;
1166                                 dma_len -= rsize;
1167                                 rsize = 0;
1168                         }
1169
1170                         ++riu->sge_cnt;
1171
1172                         if (rsize > 0 && riu->sge_cnt == SRPT_DEF_SG_PER_WQE) {
1173                                 ++ioctx->n_rdma;
1174                                 riu->sge =
1175                                     kmalloc(riu->sge_cnt * sizeof *riu->sge,
1176                                             GFP_KERNEL);
1177                                 if (!riu->sge)
1178                                         goto free_mem;
1179
1180                                 ++riu;
1181                                 riu->sge_cnt = 0;
1182                                 riu->raddr = raddr;
1183                                 riu->rkey = be32_to_cpu(db->key);
1184                         }
1185                 }
1186
1187                 ++ioctx->n_rdma;
1188                 riu->sge = kmalloc(riu->sge_cnt * sizeof *riu->sge,
1189                                    GFP_KERNEL);
1190                 if (!riu->sge)
1191                         goto free_mem;
1192         }
1193
1194         db = ioctx->rbufs;
1195         tsize = cmd->data_length;
1196         riu = ioctx->rdma_ius;
1197         sg = sg_orig;
1198         dma_len = ib_sg_dma_len(dev, &sg[0]);
1199         dma_addr = ib_sg_dma_address(dev, &sg[0]);
1200
1201         /* this second loop is really mapped sg_addres to rdma_iu->ib_sge */
1202         for (i = 0, j = 0;
1203              j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) {
1204                 rsize = be32_to_cpu(db->len);
1205                 sge = riu->sge;
1206                 k = 0;
1207
1208                 while (rsize > 0 && tsize > 0) {
1209                         sge->addr = dma_addr;
1210                         sge->lkey = ch->sport->sdev->mr->lkey;
1211
1212                         if (rsize >= dma_len) {
1213                                 sge->length =
1214                                         (tsize < dma_len) ? tsize : dma_len;
1215                                 tsize -= dma_len;
1216                                 rsize -= dma_len;
1217
1218                                 if (tsize > 0) {
1219                                         ++j;
1220                                         if (j < count) {
1221                                                 sg = sg_next(sg);
1222                                                 dma_len = ib_sg_dma_len(
1223                                                                 dev, sg);
1224                                                 dma_addr = ib_sg_dma_address(
1225                                                                 dev, sg);
1226                                         }
1227                                 }
1228                         } else {
1229                                 sge->length = (tsize < rsize) ? tsize : rsize;
1230                                 tsize -= rsize;
1231                                 dma_len -= rsize;
1232                                 dma_addr += rsize;
1233                                 rsize = 0;
1234                         }
1235
1236                         ++k;
1237                         if (k == riu->sge_cnt && rsize > 0 && tsize > 0) {
1238                                 ++riu;
1239                                 sge = riu->sge;
1240                                 k = 0;
1241                         } else if (rsize > 0 && tsize > 0)
1242                                 ++sge;
1243                 }
1244         }
1245
1246         return 0;
1247
1248 free_mem:
1249         srpt_unmap_sg_to_ib_sge(ch, ioctx);
1250
1251         return -ENOMEM;
1252 }
1253
1254 /**
1255  * srpt_get_send_ioctx() - Obtain an I/O context for sending to the initiator.
1256  */
1257 static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)
1258 {
1259         struct srpt_send_ioctx *ioctx;
1260         unsigned long flags;
1261
1262         BUG_ON(!ch);
1263
1264         ioctx = NULL;
1265         spin_lock_irqsave(&ch->spinlock, flags);
1266         if (!list_empty(&ch->free_list)) {
1267                 ioctx = list_first_entry(&ch->free_list,
1268                                          struct srpt_send_ioctx, free_list);
1269                 list_del(&ioctx->free_list);
1270         }
1271         spin_unlock_irqrestore(&ch->spinlock, flags);
1272
1273         if (!ioctx)
1274                 return ioctx;
1275
1276         BUG_ON(ioctx->ch != ch);
1277         spin_lock_init(&ioctx->spinlock);
1278         ioctx->state = SRPT_STATE_NEW;
1279         ioctx->n_rbuf = 0;
1280         ioctx->rbufs = NULL;
1281         ioctx->n_rdma = 0;
1282         ioctx->n_rdma_ius = 0;
1283         ioctx->rdma_ius = NULL;
1284         ioctx->mapped_sg_count = 0;
1285         init_completion(&ioctx->tx_done);
1286         ioctx->queue_status_only = false;
1287         /*
1288          * transport_init_se_cmd() does not initialize all fields, so do it
1289          * here.
1290          */
1291         memset(&ioctx->cmd, 0, sizeof(ioctx->cmd));
1292         memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data));
1293
1294         return ioctx;
1295 }
1296
1297 /**
1298  * srpt_abort_cmd() - Abort a SCSI command.
1299  * @ioctx:   I/O context associated with the SCSI command.
1300  * @context: Preferred execution context.
1301  */
1302 static int srpt_abort_cmd(struct srpt_send_ioctx *ioctx)
1303 {
1304         enum srpt_command_state state;
1305         unsigned long flags;
1306
1307         BUG_ON(!ioctx);
1308
1309         /*
1310          * If the command is in a state where the target core is waiting for
1311          * the ib_srpt driver, change the state to the next state. Changing
1312          * the state of the command from SRPT_STATE_NEED_DATA to
1313          * SRPT_STATE_DATA_IN ensures that srpt_xmit_response() will call this
1314          * function a second time.
1315          */
1316
1317         spin_lock_irqsave(&ioctx->spinlock, flags);
1318         state = ioctx->state;
1319         switch (state) {
1320         case SRPT_STATE_NEED_DATA:
1321                 ioctx->state = SRPT_STATE_DATA_IN;
1322                 break;
1323         case SRPT_STATE_DATA_IN:
1324         case SRPT_STATE_CMD_RSP_SENT:
1325         case SRPT_STATE_MGMT_RSP_SENT:
1326                 ioctx->state = SRPT_STATE_DONE;
1327                 break;
1328         default:
1329                 break;
1330         }
1331         spin_unlock_irqrestore(&ioctx->spinlock, flags);
1332
1333         if (state == SRPT_STATE_DONE) {
1334                 struct srpt_rdma_ch *ch = ioctx->ch;
1335
1336                 BUG_ON(ch->sess == NULL);
1337
1338                 target_put_sess_cmd(ch->sess, &ioctx->cmd);
1339                 goto out;
1340         }
1341
1342         pr_debug("Aborting cmd with state %d and tag %lld\n", state,
1343                  ioctx->tag);
1344
1345         switch (state) {
1346         case SRPT_STATE_NEW:
1347         case SRPT_STATE_DATA_IN:
1348         case SRPT_STATE_MGMT:
1349                 /*
1350                  * Do nothing - defer abort processing until
1351                  * srpt_queue_response() is invoked.
1352                  */
1353                 WARN_ON(!transport_check_aborted_status(&ioctx->cmd, false));
1354                 break;
1355         case SRPT_STATE_NEED_DATA:
1356                 /* DMA_TO_DEVICE (write) - RDMA read error. */
1357
1358                 /* XXX(hch): this is a horrible layering violation.. */
1359                 spin_lock_irqsave(&ioctx->cmd.t_state_lock, flags);
1360                 ioctx->cmd.transport_state &= ~CMD_T_ACTIVE;
1361                 spin_unlock_irqrestore(&ioctx->cmd.t_state_lock, flags);
1362                 break;
1363         case SRPT_STATE_CMD_RSP_SENT:
1364                 /*
1365                  * SRP_RSP sending failed or the SRP_RSP send completion has
1366                  * not been received in time.
1367                  */
1368                 srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx);
1369                 target_put_sess_cmd(ioctx->ch->sess, &ioctx->cmd);
1370                 break;
1371         case SRPT_STATE_MGMT_RSP_SENT:
1372                 srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
1373                 target_put_sess_cmd(ioctx->ch->sess, &ioctx->cmd);
1374                 break;
1375         default:
1376                 WARN(1, "Unexpected command state (%d)", state);
1377                 break;
1378         }
1379
1380 out:
1381         return state;
1382 }
1383
1384 /**
1385  * srpt_handle_send_err_comp() - Process an IB_WC_SEND error completion.
1386  */
1387 static void srpt_handle_send_err_comp(struct srpt_rdma_ch *ch, u64 wr_id)
1388 {
1389         struct srpt_send_ioctx *ioctx;
1390         enum srpt_command_state state;
1391         struct se_cmd *cmd;
1392         u32 index;
1393
1394         atomic_inc(&ch->sq_wr_avail);
1395
1396         index = idx_from_wr_id(wr_id);
1397         ioctx = ch->ioctx_ring[index];
1398         state = srpt_get_cmd_state(ioctx);
1399         cmd = &ioctx->cmd;
1400
1401         WARN_ON(state != SRPT_STATE_CMD_RSP_SENT
1402                 && state != SRPT_STATE_MGMT_RSP_SENT
1403                 && state != SRPT_STATE_NEED_DATA
1404                 && state != SRPT_STATE_DONE);
1405
1406         /* If SRP_RSP sending failed, undo the ch->req_lim change. */
1407         if (state == SRPT_STATE_CMD_RSP_SENT
1408             || state == SRPT_STATE_MGMT_RSP_SENT)
1409                 atomic_dec(&ch->req_lim);
1410
1411         srpt_abort_cmd(ioctx);
1412 }
1413
1414 /**
1415  * srpt_handle_send_comp() - Process an IB send completion notification.
1416  */
1417 static void srpt_handle_send_comp(struct srpt_rdma_ch *ch,
1418                                   struct srpt_send_ioctx *ioctx)
1419 {
1420         enum srpt_command_state state;
1421
1422         atomic_inc(&ch->sq_wr_avail);
1423
1424         state = srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
1425
1426         if (WARN_ON(state != SRPT_STATE_CMD_RSP_SENT
1427                     && state != SRPT_STATE_MGMT_RSP_SENT
1428                     && state != SRPT_STATE_DONE))
1429                 pr_debug("state = %d\n", state);
1430
1431         if (state != SRPT_STATE_DONE) {
1432                 srpt_unmap_sg_to_ib_sge(ch, ioctx);
1433                 transport_generic_free_cmd(&ioctx->cmd, 0);
1434         } else {
1435                 printk(KERN_ERR "IB completion has been received too late for"
1436                        " wr_id = %u.\n", ioctx->ioctx.index);
1437         }
1438 }
1439
1440 /**
1441  * srpt_handle_rdma_comp() - Process an IB RDMA completion notification.
1442  *
1443  * XXX: what is now target_execute_cmd used to be asynchronous, and unmapping
1444  * the data that has been transferred via IB RDMA had to be postponed until the
1445  * check_stop_free() callback.  None of this is necessary anymore and needs to
1446  * be cleaned up.
1447  */
1448 static void srpt_handle_rdma_comp(struct srpt_rdma_ch *ch,
1449                                   struct srpt_send_ioctx *ioctx,
1450                                   enum srpt_opcode opcode)
1451 {
1452         WARN_ON(ioctx->n_rdma <= 0);
1453         atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);
1454
1455         if (opcode == SRPT_RDMA_READ_LAST) {
1456                 if (srpt_test_and_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA,
1457                                                 SRPT_STATE_DATA_IN))
1458                         target_execute_cmd(&ioctx->cmd);
1459                 else
1460                         printk(KERN_ERR "%s[%d]: wrong state = %d\n", __func__,
1461                                __LINE__, srpt_get_cmd_state(ioctx));
1462         } else if (opcode == SRPT_RDMA_ABORT) {
1463                 ioctx->rdma_aborted = true;
1464         } else {
1465                 WARN(true, "unexpected opcode %d\n", opcode);
1466         }
1467 }
1468
1469 /**
1470  * srpt_handle_rdma_err_comp() - Process an IB RDMA error completion.
1471  */
1472 static void srpt_handle_rdma_err_comp(struct srpt_rdma_ch *ch,
1473                                       struct srpt_send_ioctx *ioctx,
1474                                       enum srpt_opcode opcode)
1475 {
1476         struct se_cmd *cmd;
1477         enum srpt_command_state state;
1478
1479         cmd = &ioctx->cmd;
1480         state = srpt_get_cmd_state(ioctx);
1481         switch (opcode) {
1482         case SRPT_RDMA_READ_LAST:
1483                 if (ioctx->n_rdma <= 0) {
1484                         printk(KERN_ERR "Received invalid RDMA read"
1485                                " error completion with idx %d\n",
1486                                ioctx->ioctx.index);
1487                         break;
1488                 }
1489                 atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);
1490                 if (state == SRPT_STATE_NEED_DATA)
1491                         srpt_abort_cmd(ioctx);
1492                 else
1493                         printk(KERN_ERR "%s[%d]: wrong state = %d\n",
1494                                __func__, __LINE__, state);
1495                 break;
1496         case SRPT_RDMA_WRITE_LAST:
1497                 break;
1498         default:
1499                 printk(KERN_ERR "%s[%d]: opcode = %u\n", __func__,
1500                        __LINE__, opcode);
1501                 break;
1502         }
1503 }
1504
1505 /**
1506  * srpt_build_cmd_rsp() - Build an SRP_RSP response.
1507  * @ch: RDMA channel through which the request has been received.
1508  * @ioctx: I/O context associated with the SRP_CMD request. The response will
1509  *   be built in the buffer ioctx->buf points at and hence this function will
1510  *   overwrite the request data.
1511  * @tag: tag of the request for which this response is being generated.
1512  * @status: value for the STATUS field of the SRP_RSP information unit.
1513  *
1514  * Returns the size in bytes of the SRP_RSP response.
1515  *
1516  * An SRP_RSP response contains a SCSI status or service response. See also
1517  * section 6.9 in the SRP r16a document for the format of an SRP_RSP
1518  * response. See also SPC-2 for more information about sense data.
1519  */
1520 static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,
1521                               struct srpt_send_ioctx *ioctx, u64 tag,
1522                               int status)
1523 {
1524         struct srp_rsp *srp_rsp;
1525         const u8 *sense_data;
1526         int sense_data_len, max_sense_len;
1527
1528         /*
1529          * The lowest bit of all SAM-3 status codes is zero (see also
1530          * paragraph 5.3 in SAM-3).
1531          */
1532         WARN_ON(status & 1);
1533
1534         srp_rsp = ioctx->ioctx.buf;
1535         BUG_ON(!srp_rsp);
1536
1537         sense_data = ioctx->sense_data;
1538         sense_data_len = ioctx->cmd.scsi_sense_length;
1539         WARN_ON(sense_data_len > sizeof(ioctx->sense_data));
1540
1541         memset(srp_rsp, 0, sizeof *srp_rsp);
1542         srp_rsp->opcode = SRP_RSP;
1543         srp_rsp->req_lim_delta =
1544                 __constant_cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0));
1545         srp_rsp->tag = tag;
1546         srp_rsp->status = status;
1547
1548         if (sense_data_len) {
1549                 BUILD_BUG_ON(MIN_MAX_RSP_SIZE <= sizeof(*srp_rsp));
1550                 max_sense_len = ch->max_ti_iu_len - sizeof(*srp_rsp);
1551                 if (sense_data_len > max_sense_len) {
1552                         printk(KERN_WARNING "truncated sense data from %d to %d"
1553                                " bytes\n", sense_data_len, max_sense_len);
1554                         sense_data_len = max_sense_len;
1555                 }
1556
1557                 srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;
1558                 srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);
1559                 memcpy(srp_rsp + 1, sense_data, sense_data_len);
1560         }
1561
1562         return sizeof(*srp_rsp) + sense_data_len;
1563 }
1564
1565 /**
1566  * srpt_build_tskmgmt_rsp() - Build a task management response.
1567  * @ch:       RDMA channel through which the request has been received.
1568  * @ioctx:    I/O context in which the SRP_RSP response will be built.
1569  * @rsp_code: RSP_CODE that will be stored in the response.
1570  * @tag:      Tag of the request for which this response is being generated.
1571  *
1572  * Returns the size in bytes of the SRP_RSP response.
1573  *
1574  * An SRP_RSP response contains a SCSI status or service response. See also
1575  * section 6.9 in the SRP r16a document for the format of an SRP_RSP
1576  * response.
1577  */
1578 static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,
1579                                   struct srpt_send_ioctx *ioctx,
1580                                   u8 rsp_code, u64 tag)
1581 {
1582         struct srp_rsp *srp_rsp;
1583         int resp_data_len;
1584         int resp_len;
1585
1586         resp_data_len = 4;
1587         resp_len = sizeof(*srp_rsp) + resp_data_len;
1588
1589         srp_rsp = ioctx->ioctx.buf;
1590         BUG_ON(!srp_rsp);
1591         memset(srp_rsp, 0, sizeof *srp_rsp);
1592
1593         srp_rsp->opcode = SRP_RSP;
1594         srp_rsp->req_lim_delta = __constant_cpu_to_be32(1
1595                                     + atomic_xchg(&ch->req_lim_delta, 0));
1596         srp_rsp->tag = tag;
1597
1598         srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID;
1599         srp_rsp->resp_data_len = cpu_to_be32(resp_data_len);
1600         srp_rsp->data[3] = rsp_code;
1601
1602         return resp_len;
1603 }
1604
1605 #define NO_SUCH_LUN ((uint64_t)-1LL)
1606
1607 /*
1608  * SCSI LUN addressing method. See also SAM-2 and the section about
1609  * eight byte LUNs.
1610  */
1611 enum scsi_lun_addr_method {
1612         SCSI_LUN_ADDR_METHOD_PERIPHERAL   = 0,
1613         SCSI_LUN_ADDR_METHOD_FLAT         = 1,
1614         SCSI_LUN_ADDR_METHOD_LUN          = 2,
1615         SCSI_LUN_ADDR_METHOD_EXTENDED_LUN = 3,
1616 };
1617
1618 /*
1619  * srpt_unpack_lun() - Convert from network LUN to linear LUN.
1620  *
1621  * Convert an 2-byte, 4-byte, 6-byte or 8-byte LUN structure in network byte
1622  * order (big endian) to a linear LUN. Supports three LUN addressing methods:
1623  * peripheral, flat and logical unit. See also SAM-2, section 4.9.4 (page 40).
1624  */
1625 static uint64_t srpt_unpack_lun(const uint8_t *lun, int len)
1626 {
1627         uint64_t res = NO_SUCH_LUN;
1628         int addressing_method;
1629
1630         if (unlikely(len < 2)) {
1631                 printk(KERN_ERR "Illegal LUN length %d, expected 2 bytes or "
1632                        "more", len);
1633                 goto out;
1634         }
1635
1636         switch (len) {
1637         case 8:
1638                 if ((*((__be64 *)lun) &
1639                      __constant_cpu_to_be64(0x0000FFFFFFFFFFFFLL)) != 0)
1640                         goto out_err;
1641                 break;
1642         case 4:
1643                 if (*((__be16 *)&lun[2]) != 0)
1644                         goto out_err;
1645                 break;
1646         case 6:
1647                 if (*((__be32 *)&lun[2]) != 0)
1648                         goto out_err;
1649                 break;
1650         case 2:
1651                 break;
1652         default:
1653                 goto out_err;
1654         }
1655
1656         addressing_method = (*lun) >> 6; /* highest two bits of byte 0 */
1657         switch (addressing_method) {
1658         case SCSI_LUN_ADDR_METHOD_PERIPHERAL:
1659         case SCSI_LUN_ADDR_METHOD_FLAT:
1660         case SCSI_LUN_ADDR_METHOD_LUN:
1661                 res = *(lun + 1) | (((*lun) & 0x3f) << 8);
1662                 break;
1663
1664         case SCSI_LUN_ADDR_METHOD_EXTENDED_LUN:
1665         default:
1666                 printk(KERN_ERR "Unimplemented LUN addressing method %u",
1667                        addressing_method);
1668                 break;
1669         }
1670
1671 out:
1672         return res;
1673
1674 out_err:
1675         printk(KERN_ERR "Support for multi-level LUNs has not yet been"
1676                " implemented");
1677         goto out;
1678 }
1679
1680 static int srpt_check_stop_free(struct se_cmd *cmd)
1681 {
1682         struct srpt_send_ioctx *ioctx = container_of(cmd,
1683                                 struct srpt_send_ioctx, cmd);
1684
1685         return target_put_sess_cmd(ioctx->ch->sess, &ioctx->cmd);
1686 }
1687
1688 /**
1689  * srpt_handle_cmd() - Process SRP_CMD.
1690  */
1691 static int srpt_handle_cmd(struct srpt_rdma_ch *ch,
1692                            struct srpt_recv_ioctx *recv_ioctx,
1693                            struct srpt_send_ioctx *send_ioctx)
1694 {
1695         struct se_cmd *cmd;
1696         struct srp_cmd *srp_cmd;
1697         uint64_t unpacked_lun;
1698         u64 data_len;
1699         enum dma_data_direction dir;
1700         sense_reason_t ret;
1701         int rc;
1702
1703         BUG_ON(!send_ioctx);
1704
1705         srp_cmd = recv_ioctx->ioctx.buf;
1706         cmd = &send_ioctx->cmd;
1707         send_ioctx->tag = srp_cmd->tag;
1708
1709         switch (srp_cmd->task_attr) {
1710         case SRP_CMD_SIMPLE_Q:
1711                 cmd->sam_task_attr = MSG_SIMPLE_TAG;
1712                 break;
1713         case SRP_CMD_ORDERED_Q:
1714         default:
1715                 cmd->sam_task_attr = MSG_ORDERED_TAG;
1716                 break;
1717         case SRP_CMD_HEAD_OF_Q:
1718                 cmd->sam_task_attr = MSG_HEAD_TAG;
1719                 break;
1720         case SRP_CMD_ACA:
1721                 cmd->sam_task_attr = MSG_ACA_TAG;
1722                 break;
1723         }
1724
1725         if (srpt_get_desc_tbl(send_ioctx, srp_cmd, &dir, &data_len)) {
1726                 printk(KERN_ERR "0x%llx: parsing SRP descriptor table failed.\n",
1727                        srp_cmd->tag);
1728                 ret = TCM_INVALID_CDB_FIELD;
1729                 goto send_sense;
1730         }
1731
1732         unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_cmd->lun,
1733                                        sizeof(srp_cmd->lun));
1734         rc = target_submit_cmd(cmd, ch->sess, srp_cmd->cdb,
1735                         &send_ioctx->sense_data[0], unpacked_lun, data_len,
1736                         MSG_SIMPLE_TAG, dir, TARGET_SCF_ACK_KREF);
1737         if (rc != 0) {
1738                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1739                 goto send_sense;
1740         }
1741         return 0;
1742
1743 send_sense:
1744         transport_send_check_condition_and_sense(cmd, ret, 0);
1745         return -1;
1746 }
1747
1748 /**
1749  * srpt_rx_mgmt_fn_tag() - Process a task management function by tag.
1750  * @ch: RDMA channel of the task management request.
1751  * @fn: Task management function to perform.
1752  * @req_tag: Tag of the SRP task management request.
1753  * @mgmt_ioctx: I/O context of the task management request.
1754  *
1755  * Returns zero if the target core will process the task management
1756  * request asynchronously.
1757  *
1758  * Note: It is assumed that the initiator serializes tag-based task management
1759  * requests.
1760  */
1761 static int srpt_rx_mgmt_fn_tag(struct srpt_send_ioctx *ioctx, u64 tag)
1762 {
1763         struct srpt_device *sdev;
1764         struct srpt_rdma_ch *ch;
1765         struct srpt_send_ioctx *target;
1766         int ret, i;
1767
1768         ret = -EINVAL;
1769         ch = ioctx->ch;
1770         BUG_ON(!ch);
1771         BUG_ON(!ch->sport);
1772         sdev = ch->sport->sdev;
1773         BUG_ON(!sdev);
1774         spin_lock_irq(&sdev->spinlock);
1775         for (i = 0; i < ch->rq_size; ++i) {
1776                 target = ch->ioctx_ring[i];
1777                 if (target->cmd.se_lun == ioctx->cmd.se_lun &&
1778                     target->tag == tag &&
1779                     srpt_get_cmd_state(target) != SRPT_STATE_DONE) {
1780                         ret = 0;
1781                         /* now let the target core abort &target->cmd; */
1782                         break;
1783                 }
1784         }
1785         spin_unlock_irq(&sdev->spinlock);
1786         return ret;
1787 }
1788
1789 static int srp_tmr_to_tcm(int fn)
1790 {
1791         switch (fn) {
1792         case SRP_TSK_ABORT_TASK:
1793                 return TMR_ABORT_TASK;
1794         case SRP_TSK_ABORT_TASK_SET:
1795                 return TMR_ABORT_TASK_SET;
1796         case SRP_TSK_CLEAR_TASK_SET:
1797                 return TMR_CLEAR_TASK_SET;
1798         case SRP_TSK_LUN_RESET:
1799                 return TMR_LUN_RESET;
1800         case SRP_TSK_CLEAR_ACA:
1801                 return TMR_CLEAR_ACA;
1802         default:
1803                 return -1;
1804         }
1805 }
1806
1807 /**
1808  * srpt_handle_tsk_mgmt() - Process an SRP_TSK_MGMT information unit.
1809  *
1810  * Returns 0 if and only if the request will be processed by the target core.
1811  *
1812  * For more information about SRP_TSK_MGMT information units, see also section
1813  * 6.7 in the SRP r16a document.
1814  */
1815 static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,
1816                                  struct srpt_recv_ioctx *recv_ioctx,
1817                                  struct srpt_send_ioctx *send_ioctx)
1818 {
1819         struct srp_tsk_mgmt *srp_tsk;
1820         struct se_cmd *cmd;
1821         struct se_session *sess = ch->sess;
1822         uint64_t unpacked_lun;
1823         uint32_t tag = 0;
1824         int tcm_tmr;
1825         int rc;
1826
1827         BUG_ON(!send_ioctx);
1828
1829         srp_tsk = recv_ioctx->ioctx.buf;
1830         cmd = &send_ioctx->cmd;
1831
1832         pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld"
1833                  " cm_id %p sess %p\n", srp_tsk->tsk_mgmt_func,
1834                  srp_tsk->task_tag, srp_tsk->tag, ch->cm_id, ch->sess);
1835
1836         srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT);
1837         send_ioctx->tag = srp_tsk->tag;
1838         tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func);
1839         if (tcm_tmr < 0) {
1840                 send_ioctx->cmd.se_tmr_req->response =
1841                         TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
1842                 goto fail;
1843         }
1844         unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_tsk->lun,
1845                                        sizeof(srp_tsk->lun));
1846
1847         if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK) {
1848                 rc = srpt_rx_mgmt_fn_tag(send_ioctx, srp_tsk->task_tag);
1849                 if (rc < 0) {
1850                         send_ioctx->cmd.se_tmr_req->response =
1851                                         TMR_TASK_DOES_NOT_EXIST;
1852                         goto fail;
1853                 }
1854                 tag = srp_tsk->task_tag;
1855         }
1856         rc = target_submit_tmr(&send_ioctx->cmd, sess, NULL, unpacked_lun,
1857                                 srp_tsk, tcm_tmr, GFP_KERNEL, tag,
1858                                 TARGET_SCF_ACK_KREF);
1859         if (rc != 0) {
1860                 send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED;
1861                 goto fail;
1862         }
1863         return;
1864 fail:
1865         transport_send_check_condition_and_sense(cmd, 0, 0); // XXX:
1866 }
1867
1868 /**
1869  * srpt_handle_new_iu() - Process a newly received information unit.
1870  * @ch:    RDMA channel through which the information unit has been received.
1871  * @ioctx: SRPT I/O context associated with the information unit.
1872  */
1873 static void srpt_handle_new_iu(struct srpt_rdma_ch *ch,
1874                                struct srpt_recv_ioctx *recv_ioctx,
1875                                struct srpt_send_ioctx *send_ioctx)
1876 {
1877         struct srp_cmd *srp_cmd;
1878         enum rdma_ch_state ch_state;
1879
1880         BUG_ON(!ch);
1881         BUG_ON(!recv_ioctx);
1882
1883         ib_dma_sync_single_for_cpu(ch->sport->sdev->device,
1884                                    recv_ioctx->ioctx.dma, srp_max_req_size,
1885                                    DMA_FROM_DEVICE);
1886
1887         ch_state = srpt_get_ch_state(ch);
1888         if (unlikely(ch_state == CH_CONNECTING)) {
1889                 list_add_tail(&recv_ioctx->wait_list, &ch->cmd_wait_list);
1890                 goto out;
1891         }
1892
1893         if (unlikely(ch_state != CH_LIVE))
1894                 goto out;
1895
1896         srp_cmd = recv_ioctx->ioctx.buf;
1897         if (srp_cmd->opcode == SRP_CMD || srp_cmd->opcode == SRP_TSK_MGMT) {
1898                 if (!send_ioctx)
1899                         send_ioctx = srpt_get_send_ioctx(ch);
1900                 if (unlikely(!send_ioctx)) {
1901                         list_add_tail(&recv_ioctx->wait_list,
1902                                       &ch->cmd_wait_list);
1903                         goto out;
1904                 }
1905         }
1906
1907         switch (srp_cmd->opcode) {
1908         case SRP_CMD:
1909                 srpt_handle_cmd(ch, recv_ioctx, send_ioctx);
1910                 break;
1911         case SRP_TSK_MGMT:
1912                 srpt_handle_tsk_mgmt(ch, recv_ioctx, send_ioctx);
1913                 break;
1914         case SRP_I_LOGOUT:
1915                 printk(KERN_ERR "Not yet implemented: SRP_I_LOGOUT\n");
1916                 break;
1917         case SRP_CRED_RSP:
1918                 pr_debug("received SRP_CRED_RSP\n");
1919                 break;
1920         case SRP_AER_RSP:
1921                 pr_debug("received SRP_AER_RSP\n");
1922                 break;
1923         case SRP_RSP:
1924                 printk(KERN_ERR "Received SRP_RSP\n");
1925                 break;
1926         default:
1927                 printk(KERN_ERR "received IU with unknown opcode 0x%x\n",
1928                        srp_cmd->opcode);
1929                 break;
1930         }
1931
1932         srpt_post_recv(ch->sport->sdev, recv_ioctx);
1933 out:
1934         return;
1935 }
1936
1937 static void srpt_process_rcv_completion(struct ib_cq *cq,
1938                                         struct srpt_rdma_ch *ch,
1939                                         struct ib_wc *wc)
1940 {
1941         struct srpt_device *sdev = ch->sport->sdev;
1942         struct srpt_recv_ioctx *ioctx;
1943         u32 index;
1944
1945         index = idx_from_wr_id(wc->wr_id);
1946         if (wc->status == IB_WC_SUCCESS) {
1947                 int req_lim;
1948
1949                 req_lim = atomic_dec_return(&ch->req_lim);
1950                 if (unlikely(req_lim < 0))
1951                         printk(KERN_ERR "req_lim = %d < 0\n", req_lim);
1952                 ioctx = sdev->ioctx_ring[index];
1953                 srpt_handle_new_iu(ch, ioctx, NULL);
1954         } else {
1955                 printk(KERN_INFO "receiving failed for idx %u with status %d\n",
1956                        index, wc->status);
1957         }
1958 }
1959
1960 /**
1961  * srpt_process_send_completion() - Process an IB send completion.
1962  *
1963  * Note: Although this has not yet been observed during tests, at least in
1964  * theory it is possible that the srpt_get_send_ioctx() call invoked by
1965  * srpt_handle_new_iu() fails. This is possible because the req_lim_delta
1966  * value in each response is set to one, and it is possible that this response
1967  * makes the initiator send a new request before the send completion for that
1968  * response has been processed. This could e.g. happen if the call to
1969  * srpt_put_send_iotcx() is delayed because of a higher priority interrupt or
1970  * if IB retransmission causes generation of the send completion to be
1971  * delayed. Incoming information units for which srpt_get_send_ioctx() fails
1972  * are queued on cmd_wait_list. The code below processes these delayed
1973  * requests one at a time.
1974  */
1975 static void srpt_process_send_completion(struct ib_cq *cq,
1976                                          struct srpt_rdma_ch *ch,
1977                                          struct ib_wc *wc)
1978 {
1979         struct srpt_send_ioctx *send_ioctx;
1980         uint32_t index;
1981         enum srpt_opcode opcode;
1982
1983         index = idx_from_wr_id(wc->wr_id);
1984         opcode = opcode_from_wr_id(wc->wr_id);
1985         send_ioctx = ch->ioctx_ring[index];
1986         if (wc->status == IB_WC_SUCCESS) {
1987                 if (opcode == SRPT_SEND)
1988                         srpt_handle_send_comp(ch, send_ioctx);
1989                 else {
1990                         WARN_ON(opcode != SRPT_RDMA_ABORT &&
1991                                 wc->opcode != IB_WC_RDMA_READ);
1992                         srpt_handle_rdma_comp(ch, send_ioctx, opcode);
1993                 }
1994         } else {
1995                 if (opcode == SRPT_SEND) {
1996                         printk(KERN_INFO "sending response for idx %u failed"
1997                                " with status %d\n", index, wc->status);
1998                         srpt_handle_send_err_comp(ch, wc->wr_id);
1999                 } else if (opcode != SRPT_RDMA_MID) {
2000                         printk(KERN_INFO "RDMA t %d for idx %u failed with"
2001                                 " status %d", opcode, index, wc->status);
2002                         srpt_handle_rdma_err_comp(ch, send_ioctx, opcode);
2003                 }
2004         }
2005
2006         while (unlikely(opcode == SRPT_SEND
2007                         && !list_empty(&ch->cmd_wait_list)
2008                         && srpt_get_ch_state(ch) == CH_LIVE
2009                         && (send_ioctx = srpt_get_send_ioctx(ch)) != NULL)) {
2010                 struct srpt_recv_ioctx *recv_ioctx;
2011
2012                 recv_ioctx = list_first_entry(&ch->cmd_wait_list,
2013                                               struct srpt_recv_ioctx,
2014                                               wait_list);
2015                 list_del(&recv_ioctx->wait_list);
2016                 srpt_handle_new_iu(ch, recv_ioctx, send_ioctx);
2017         }
2018 }
2019
2020 static void srpt_process_completion(struct ib_cq *cq, struct srpt_rdma_ch *ch)
2021 {
2022         struct ib_wc *const wc = ch->wc;
2023         int i, n;
2024
2025         WARN_ON(cq != ch->cq);
2026
2027         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
2028         while ((n = ib_poll_cq(cq, ARRAY_SIZE(ch->wc), wc)) > 0) {
2029                 for (i = 0; i < n; i++) {
2030                         if (opcode_from_wr_id(wc[i].wr_id) == SRPT_RECV)
2031                                 srpt_process_rcv_completion(cq, ch, &wc[i]);
2032                         else
2033                                 srpt_process_send_completion(cq, ch, &wc[i]);
2034                 }
2035         }
2036 }
2037
2038 /**
2039  * srpt_completion() - IB completion queue callback function.
2040  *
2041  * Notes:
2042  * - It is guaranteed that a completion handler will never be invoked
2043  *   concurrently on two different CPUs for the same completion queue. See also
2044  *   Documentation/infiniband/core_locking.txt and the implementation of
2045  *   handle_edge_irq() in kernel/irq/chip.c.
2046  * - When threaded IRQs are enabled, completion handlers are invoked in thread
2047  *   context instead of interrupt context.
2048  */
2049 static void srpt_completion(struct ib_cq *cq, void *ctx)
2050 {
2051         struct srpt_rdma_ch *ch = ctx;
2052
2053         wake_up_interruptible(&ch->wait_queue);
2054 }
2055
2056 static int srpt_compl_thread(void *arg)
2057 {
2058         struct srpt_rdma_ch *ch;
2059
2060         /* Hibernation / freezing of the SRPT kernel thread is not supported. */
2061         current->flags |= PF_NOFREEZE;
2062
2063         ch = arg;
2064         BUG_ON(!ch);
2065         printk(KERN_INFO "Session %s: kernel thread %s (PID %d) started\n",
2066                ch->sess_name, ch->thread->comm, current->pid);
2067         while (!kthread_should_stop()) {
2068                 wait_event_interruptible(ch->wait_queue,
2069                         (srpt_process_completion(ch->cq, ch),
2070                          kthread_should_stop()));
2071         }
2072         printk(KERN_INFO "Session %s: kernel thread %s (PID %d) stopped\n",
2073                ch->sess_name, ch->thread->comm, current->pid);
2074         return 0;
2075 }
2076
2077 /**
2078  * srpt_create_ch_ib() - Create receive and send completion queues.
2079  */
2080 static int srpt_create_ch_ib(struct srpt_rdma_ch *ch)
2081 {
2082         struct ib_qp_init_attr *qp_init;
2083         struct srpt_port *sport = ch->sport;
2084         struct srpt_device *sdev = sport->sdev;
2085         u32 srp_sq_size = sport->port_attrib.srp_sq_size;
2086         int ret;
2087
2088         WARN_ON(ch->rq_size < 1);
2089
2090         ret = -ENOMEM;
2091         qp_init = kzalloc(sizeof *qp_init, GFP_KERNEL);
2092         if (!qp_init)
2093                 goto out;
2094
2095 retry:
2096         ch->cq = ib_create_cq(sdev->device, srpt_completion, NULL, ch,
2097                               ch->rq_size + srp_sq_size, 0);
2098         if (IS_ERR(ch->cq)) {
2099                 ret = PTR_ERR(ch->cq);
2100                 printk(KERN_ERR "failed to create CQ cqe= %d ret= %d\n",
2101                        ch->rq_size + srp_sq_size, ret);
2102                 goto out;
2103         }
2104
2105         qp_init->qp_context = (void *)ch;
2106         qp_init->event_handler
2107                 = (void(*)(struct ib_event *, void*))srpt_qp_event;
2108         qp_init->send_cq = ch->cq;
2109         qp_init->recv_cq = ch->cq;
2110         qp_init->srq = sdev->srq;
2111         qp_init->sq_sig_type = IB_SIGNAL_REQ_WR;
2112         qp_init->qp_type = IB_QPT_RC;
2113         qp_init->cap.max_send_wr = srp_sq_size;
2114         qp_init->cap.max_send_sge = SRPT_DEF_SG_PER_WQE;
2115
2116         ch->qp = ib_create_qp(sdev->pd, qp_init);
2117         if (IS_ERR(ch->qp)) {
2118                 ret = PTR_ERR(ch->qp);
2119                 if (ret == -ENOMEM) {
2120                         srp_sq_size /= 2;
2121                         if (srp_sq_size >= MIN_SRPT_SQ_SIZE) {
2122                                 ib_destroy_cq(ch->cq);
2123                                 goto retry;
2124                         }
2125                 }
2126                 printk(KERN_ERR "failed to create_qp ret= %d\n", ret);
2127                 goto err_destroy_cq;
2128         }
2129
2130         atomic_set(&ch->sq_wr_avail, qp_init->cap.max_send_wr);
2131
2132         pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n",
2133                  __func__, ch->cq->cqe, qp_init->cap.max_send_sge,
2134                  qp_init->cap.max_send_wr, ch->cm_id);
2135
2136         ret = srpt_init_ch_qp(ch, ch->qp);
2137         if (ret)
2138                 goto err_destroy_qp;
2139
2140         init_waitqueue_head(&ch->wait_queue);
2141
2142         pr_debug("creating thread for session %s\n", ch->sess_name);
2143
2144         ch->thread = kthread_run(srpt_compl_thread, ch, "ib_srpt_compl");
2145         if (IS_ERR(ch->thread)) {
2146                 printk(KERN_ERR "failed to create kernel thread %ld\n",
2147                        PTR_ERR(ch->thread));
2148                 ch->thread = NULL;
2149                 goto err_destroy_qp;
2150         }
2151
2152 out:
2153         kfree(qp_init);
2154         return ret;
2155
2156 err_destroy_qp:
2157         ib_destroy_qp(ch->qp);
2158 err_destroy_cq:
2159         ib_destroy_cq(ch->cq);
2160         goto out;
2161 }
2162
2163 static void srpt_destroy_ch_ib(struct srpt_rdma_ch *ch)
2164 {
2165         if (ch->thread)
2166                 kthread_stop(ch->thread);
2167
2168         ib_destroy_qp(ch->qp);
2169         ib_destroy_cq(ch->cq);
2170 }
2171
2172 /**
2173  * __srpt_close_ch() - Close an RDMA channel by setting the QP error state.
2174  *
2175  * Reset the QP and make sure all resources associated with the channel will
2176  * be deallocated at an appropriate time.
2177  *
2178  * Note: The caller must hold ch->sport->sdev->spinlock.
2179  */
2180 static void __srpt_close_ch(struct srpt_rdma_ch *ch)
2181 {
2182         struct srpt_device *sdev;
2183         enum rdma_ch_state prev_state;
2184         unsigned long flags;
2185
2186         sdev = ch->sport->sdev;
2187
2188         spin_lock_irqsave(&ch->spinlock, flags);
2189         prev_state = ch->state;
2190         switch (prev_state) {
2191         case CH_CONNECTING:
2192         case CH_LIVE:
2193                 ch->state = CH_DISCONNECTING;
2194                 break;
2195         default:
2196                 break;
2197         }
2198         spin_unlock_irqrestore(&ch->spinlock, flags);
2199
2200         switch (prev_state) {
2201         case CH_CONNECTING:
2202                 ib_send_cm_rej(ch->cm_id, IB_CM_REJ_NO_RESOURCES, NULL, 0,
2203                                NULL, 0);
2204                 /* fall through */
2205         case CH_LIVE:
2206                 if (ib_send_cm_dreq(ch->cm_id, NULL, 0) < 0)
2207                         printk(KERN_ERR "sending CM DREQ failed.\n");
2208                 break;
2209         case CH_DISCONNECTING:
2210                 break;
2211         case CH_DRAINING:
2212         case CH_RELEASING:
2213                 break;
2214         }
2215 }
2216
2217 /**
2218  * srpt_close_ch() - Close an RDMA channel.
2219  */
2220 static void srpt_close_ch(struct srpt_rdma_ch *ch)
2221 {
2222         struct srpt_device *sdev;
2223
2224         sdev = ch->sport->sdev;
2225         spin_lock_irq(&sdev->spinlock);
2226         __srpt_close_ch(ch);
2227         spin_unlock_irq(&sdev->spinlock);
2228 }
2229
2230 /**
2231  * srpt_shutdown_session() - Whether or not a session may be shut down.
2232  */
2233 static int srpt_shutdown_session(struct se_session *se_sess)
2234 {
2235         struct srpt_rdma_ch *ch = se_sess->fabric_sess_ptr;
2236         unsigned long flags;
2237
2238         spin_lock_irqsave(&ch->spinlock, flags);
2239         if (ch->in_shutdown) {
2240                 spin_unlock_irqrestore(&ch->spinlock, flags);
2241                 return true;
2242         }
2243
2244         ch->in_shutdown = true;
2245         target_sess_cmd_list_set_waiting(se_sess);
2246         spin_unlock_irqrestore(&ch->spinlock, flags);
2247
2248         return true;
2249 }
2250
2251 /**
2252  * srpt_drain_channel() - Drain a channel by resetting the IB queue pair.
2253  * @cm_id: Pointer to the CM ID of the channel to be drained.
2254  *
2255  * Note: Must be called from inside srpt_cm_handler to avoid a race between
2256  * accessing sdev->spinlock and the call to kfree(sdev) in srpt_remove_one()
2257  * (the caller of srpt_cm_handler holds the cm_id spinlock; srpt_remove_one()
2258  * waits until all target sessions for the associated IB device have been
2259  * unregistered and target session registration involves a call to
2260  * ib_destroy_cm_id(), which locks the cm_id spinlock and hence waits until
2261  * this function has finished).
2262  */
2263 static void srpt_drain_channel(struct ib_cm_id *cm_id)
2264 {
2265         struct srpt_device *sdev;
2266         struct srpt_rdma_ch *ch;
2267         int ret;
2268         bool do_reset = false;
2269
2270         WARN_ON_ONCE(irqs_disabled());
2271
2272         sdev = cm_id->context;
2273         BUG_ON(!sdev);
2274         spin_lock_irq(&sdev->spinlock);
2275         list_for_each_entry(ch, &sdev->rch_list, list) {
2276                 if (ch->cm_id == cm_id) {
2277                         do_reset = srpt_test_and_set_ch_state(ch,
2278                                         CH_CONNECTING, CH_DRAINING) ||
2279                                    srpt_test_and_set_ch_state(ch,
2280                                         CH_LIVE, CH_DRAINING) ||
2281                                    srpt_test_and_set_ch_state(ch,
2282                                         CH_DISCONNECTING, CH_DRAINING);
2283                         break;
2284                 }
2285         }
2286         spin_unlock_irq(&sdev->spinlock);
2287
2288         if (do_reset) {
2289                 if (ch->sess)
2290                         srpt_shutdown_session(ch->sess);
2291
2292                 ret = srpt_ch_qp_err(ch);
2293                 if (ret < 0)
2294                         printk(KERN_ERR "Setting queue pair in error state"
2295                                " failed: %d\n", ret);
2296         }
2297 }
2298
2299 /**
2300  * srpt_find_channel() - Look up an RDMA channel.
2301  * @cm_id: Pointer to the CM ID of the channel to be looked up.
2302  *
2303  * Return NULL if no matching RDMA channel has been found.
2304  */
2305 static struct srpt_rdma_ch *srpt_find_channel(struct srpt_device *sdev,
2306                                               struct ib_cm_id *cm_id)
2307 {
2308         struct srpt_rdma_ch *ch;
2309         bool found;
2310
2311         WARN_ON_ONCE(irqs_disabled());
2312         BUG_ON(!sdev);
2313
2314         found = false;
2315         spin_lock_irq(&sdev->spinlock);
2316         list_for_each_entry(ch, &sdev->rch_list, list) {
2317                 if (ch->cm_id == cm_id) {
2318                         found = true;
2319                         break;
2320                 }
2321         }
2322         spin_unlock_irq(&sdev->spinlock);
2323
2324         return found ? ch : NULL;
2325 }
2326
2327 /**
2328  * srpt_release_channel() - Release channel resources.
2329  *
2330  * Schedules the actual release because:
2331  * - Calling the ib_destroy_cm_id() call from inside an IB CM callback would
2332  *   trigger a deadlock.
2333  * - It is not safe to call TCM transport_* functions from interrupt context.
2334  */
2335 static void srpt_release_channel(struct srpt_rdma_ch *ch)
2336 {
2337         schedule_work(&ch->release_work);
2338 }
2339
2340 static void srpt_release_channel_work(struct work_struct *w)
2341 {
2342         struct srpt_rdma_ch *ch;
2343         struct srpt_device *sdev;
2344         struct se_session *se_sess;
2345
2346         ch = container_of(w, struct srpt_rdma_ch, release_work);
2347         pr_debug("ch = %p; ch->sess = %p; release_done = %p\n", ch, ch->sess,
2348                  ch->release_done);
2349
2350         sdev = ch->sport->sdev;
2351         BUG_ON(!sdev);
2352
2353         se_sess = ch->sess;
2354         BUG_ON(!se_sess);
2355
2356         target_wait_for_sess_cmds(se_sess);
2357
2358         transport_deregister_session_configfs(se_sess);
2359         transport_deregister_session(se_sess);
2360         ch->sess = NULL;
2361
2362         ib_destroy_cm_id(ch->cm_id);
2363
2364         srpt_destroy_ch_ib(ch);
2365
2366         srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
2367                              ch->sport->sdev, ch->rq_size,
2368                              ch->rsp_size, DMA_TO_DEVICE);
2369
2370         spin_lock_irq(&sdev->spinlock);
2371         list_del(&ch->list);
2372         spin_unlock_irq(&sdev->spinlock);
2373
2374         if (ch->release_done)
2375                 complete(ch->release_done);
2376
2377         wake_up(&sdev->ch_releaseQ);
2378
2379         kfree(ch);
2380 }
2381
2382 static struct srpt_node_acl *__srpt_lookup_acl(struct srpt_port *sport,
2383                                                u8 i_port_id[16])
2384 {
2385         struct srpt_node_acl *nacl;
2386
2387         list_for_each_entry(nacl, &sport->port_acl_list, list)
2388                 if (memcmp(nacl->i_port_id, i_port_id,
2389                            sizeof(nacl->i_port_id)) == 0)
2390                         return nacl;
2391
2392         return NULL;
2393 }
2394
2395 static struct srpt_node_acl *srpt_lookup_acl(struct srpt_port *sport,
2396                                              u8 i_port_id[16])
2397 {
2398         struct srpt_node_acl *nacl;
2399
2400         spin_lock_irq(&sport->port_acl_lock);
2401         nacl = __srpt_lookup_acl(sport, i_port_id);
2402         spin_unlock_irq(&sport->port_acl_lock);
2403
2404         return nacl;
2405 }
2406
2407 /**
2408  * srpt_cm_req_recv() - Process the event IB_CM_REQ_RECEIVED.
2409  *
2410  * Ownership of the cm_id is transferred to the target session if this
2411  * functions returns zero. Otherwise the caller remains the owner of cm_id.
2412  */
2413 static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
2414                             struct ib_cm_req_event_param *param,
2415                             void *private_data)
2416 {
2417         struct srpt_device *sdev = cm_id->context;
2418         struct srpt_port *sport = &sdev->port[param->port - 1];
2419         struct srp_login_req *req;
2420         struct srp_login_rsp *rsp;
2421         struct srp_login_rej *rej;
2422         struct ib_cm_rep_param *rep_param;
2423         struct srpt_rdma_ch *ch, *tmp_ch;
2424         struct srpt_node_acl *nacl;
2425         u32 it_iu_len;
2426         int i;
2427         int ret = 0;
2428
2429         WARN_ON_ONCE(irqs_disabled());
2430
2431         if (WARN_ON(!sdev || !private_data))
2432                 return -EINVAL;
2433
2434         req = (struct srp_login_req *)private_data;
2435
2436         it_iu_len = be32_to_cpu(req->req_it_iu_len);
2437
2438         printk(KERN_INFO "Received SRP_LOGIN_REQ with i_port_id 0x%llx:0x%llx,"
2439                " t_port_id 0x%llx:0x%llx and it_iu_len %d on port %d"
2440                " (guid=0x%llx:0x%llx)\n",
2441                be64_to_cpu(*(__be64 *)&req->initiator_port_id[0]),
2442                be64_to_cpu(*(__be64 *)&req->initiator_port_id[8]),
2443                be64_to_cpu(*(__be64 *)&req->target_port_id[0]),
2444                be64_to_cpu(*(__be64 *)&req->target_port_id[8]),
2445                it_iu_len,
2446                param->port,
2447                be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[0]),
2448                be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[8]));
2449
2450         rsp = kzalloc(sizeof *rsp, GFP_KERNEL);
2451         rej = kzalloc(sizeof *rej, GFP_KERNEL);
2452         rep_param = kzalloc(sizeof *rep_param, GFP_KERNEL);
2453
2454         if (!rsp || !rej || !rep_param) {
2455                 ret = -ENOMEM;
2456                 goto out;
2457         }
2458
2459         if (it_iu_len > srp_max_req_size || it_iu_len < 64) {
2460                 rej->reason = __constant_cpu_to_be32(
2461                                 SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE);
2462                 ret = -EINVAL;
2463                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because its"
2464                        " length (%d bytes) is out of range (%d .. %d)\n",
2465                        it_iu_len, 64, srp_max_req_size);
2466                 goto reject;
2467         }
2468
2469         if (!sport->enabled) {
2470                 rej->reason = __constant_cpu_to_be32(
2471                              SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2472                 ret = -EINVAL;
2473                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because the target port"
2474                        " has not yet been enabled\n");
2475                 goto reject;
2476         }
2477
2478         if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {
2479                 rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN;
2480
2481                 spin_lock_irq(&sdev->spinlock);
2482
2483                 list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) {
2484                         if (!memcmp(ch->i_port_id, req->initiator_port_id, 16)
2485                             && !memcmp(ch->t_port_id, req->target_port_id, 16)
2486                             && param->port == ch->sport->port
2487                             && param->listen_id == ch->sport->sdev->cm_id
2488                             && ch->cm_id) {
2489                                 enum rdma_ch_state ch_state;
2490
2491                                 ch_state = srpt_get_ch_state(ch);
2492                                 if (ch_state != CH_CONNECTING
2493                                     && ch_state != CH_LIVE)
2494                                         continue;
2495
2496                                 /* found an existing channel */
2497                                 pr_debug("Found existing channel %s"
2498                                          " cm_id= %p state= %d\n",
2499                                          ch->sess_name, ch->cm_id, ch_state);
2500
2501                                 __srpt_close_ch(ch);
2502
2503                                 rsp->rsp_flags =
2504                                         SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
2505                         }
2506                 }
2507
2508                 spin_unlock_irq(&sdev->spinlock);
2509
2510         } else
2511                 rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
2512
2513         if (*(__be64 *)req->target_port_id != cpu_to_be64(srpt_service_guid)
2514             || *(__be64 *)(req->target_port_id + 8) !=
2515                cpu_to_be64(srpt_service_guid)) {
2516                 rej->reason = __constant_cpu_to_be32(
2517                                 SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL);
2518                 ret = -ENOMEM;
2519                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because it"
2520                        " has an invalid target port identifier.\n");
2521                 goto reject;
2522         }
2523
2524         ch = kzalloc(sizeof *ch, GFP_KERNEL);
2525         if (!ch) {
2526                 rej->reason = __constant_cpu_to_be32(
2527                                         SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2528                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because no memory.\n");
2529                 ret = -ENOMEM;
2530                 goto reject;
2531         }
2532
2533         INIT_WORK(&ch->release_work, srpt_release_channel_work);
2534         memcpy(ch->i_port_id, req->initiator_port_id, 16);
2535         memcpy(ch->t_port_id, req->target_port_id, 16);
2536         ch->sport = &sdev->port[param->port - 1];
2537         ch->cm_id = cm_id;
2538         /*
2539          * Avoid QUEUE_FULL conditions by limiting the number of buffers used
2540          * for the SRP protocol to the command queue size.
2541          */
2542         ch->rq_size = SRPT_RQ_SIZE;
2543         spin_lock_init(&ch->spinlock);
2544         ch->state = CH_CONNECTING;
2545         INIT_LIST_HEAD(&ch->cmd_wait_list);
2546         ch->rsp_size = ch->sport->port_attrib.srp_max_rsp_size;
2547
2548         ch->ioctx_ring = (struct srpt_send_ioctx **)
2549                 srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,
2550                                       sizeof(*ch->ioctx_ring[0]),
2551                                       ch->rsp_size, DMA_TO_DEVICE);
2552         if (!ch->ioctx_ring)
2553                 goto free_ch;
2554
2555         INIT_LIST_HEAD(&ch->free_list);
2556         for (i = 0; i < ch->rq_size; i++) {
2557                 ch->ioctx_ring[i]->ch = ch;
2558                 list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
2559         }
2560
2561         ret = srpt_create_ch_ib(ch);
2562         if (ret) {
2563                 rej->reason = __constant_cpu_to_be32(
2564                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2565                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because creating"
2566                        " a new RDMA channel failed.\n");
2567                 goto free_ring;
2568         }
2569
2570         ret = srpt_ch_qp_rtr(ch, ch->qp);
2571         if (ret) {
2572                 rej->reason = __constant_cpu_to_be32(
2573                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2574                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because enabling"
2575                        " RTR failed (error code = %d)\n", ret);
2576                 goto destroy_ib;
2577         }
2578         /*
2579          * Use the initator port identifier as the session name.
2580          */
2581         snprintf(ch->sess_name, sizeof(ch->sess_name), "0x%016llx%016llx",
2582                         be64_to_cpu(*(__be64 *)ch->i_port_id),
2583                         be64_to_cpu(*(__be64 *)(ch->i_port_id + 8)));
2584
2585         pr_debug("registering session %s\n", ch->sess_name);
2586
2587         nacl = srpt_lookup_acl(sport, ch->i_port_id);
2588         if (!nacl) {
2589                 printk(KERN_INFO "Rejected login because no ACL has been"
2590                        " configured yet for initiator %s.\n", ch->sess_name);
2591                 rej->reason = __constant_cpu_to_be32(
2592                                 SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED);
2593                 goto destroy_ib;
2594         }
2595
2596         ch->sess = transport_init_session(TARGET_PROT_NORMAL);
2597         if (IS_ERR(ch->sess)) {
2598                 rej->reason = __constant_cpu_to_be32(
2599                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2600                 pr_debug("Failed to create session\n");
2601                 goto deregister_session;
2602         }
2603         ch->sess->se_node_acl = &nacl->nacl;
2604         transport_register_session(&sport->port_tpg_1, &nacl->nacl, ch->sess, ch);
2605
2606         pr_debug("Establish connection sess=%p name=%s cm_id=%p\n", ch->sess,
2607                  ch->sess_name, ch->cm_id);
2608
2609         /* create srp_login_response */
2610         rsp->opcode = SRP_LOGIN_RSP;
2611         rsp->tag = req->tag;
2612         rsp->max_it_iu_len = req->req_it_iu_len;
2613         rsp->max_ti_iu_len = req->req_it_iu_len;
2614         ch->max_ti_iu_len = it_iu_len;
2615         rsp->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT
2616                                               | SRP_BUF_FORMAT_INDIRECT);
2617         rsp->req_lim_delta = cpu_to_be32(ch->rq_size);
2618         atomic_set(&ch->req_lim, ch->rq_size);
2619         atomic_set(&ch->req_lim_delta, 0);
2620
2621         /* create cm reply */
2622         rep_param->qp_num = ch->qp->qp_num;
2623         rep_param->private_data = (void *)rsp;
2624         rep_param->private_data_len = sizeof *rsp;
2625         rep_param->rnr_retry_count = 7;
2626         rep_param->flow_control = 1;
2627         rep_param->failover_accepted = 0;
2628         rep_param->srq = 1;
2629         rep_param->responder_resources = 4;
2630         rep_param->initiator_depth = 4;
2631
2632         ret = ib_send_cm_rep(cm_id, rep_param);
2633         if (ret) {
2634                 printk(KERN_ERR "sending SRP_LOGIN_REQ response failed"
2635                        " (error code = %d)\n", ret);
2636                 goto release_channel;
2637         }
2638
2639         spin_lock_irq(&sdev->spinlock);
2640         list_add_tail(&ch->list, &sdev->rch_list);
2641         spin_unlock_irq(&sdev->spinlock);
2642
2643         goto out;
2644
2645 release_channel:
2646         srpt_set_ch_state(ch, CH_RELEASING);
2647         transport_deregister_session_configfs(ch->sess);
2648
2649 deregister_session:
2650         transport_deregister_session(ch->sess);
2651         ch->sess = NULL;
2652
2653 destroy_ib:
2654         srpt_destroy_ch_ib(ch);
2655
2656 free_ring:
2657         srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
2658                              ch->sport->sdev, ch->rq_size,
2659                              ch->rsp_size, DMA_TO_DEVICE);
2660 free_ch:
2661         kfree(ch);
2662
2663 reject:
2664         rej->opcode = SRP_LOGIN_REJ;
2665         rej->tag = req->tag;
2666         rej->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT
2667                                               | SRP_BUF_FORMAT_INDIRECT);
2668
2669         ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED, NULL, 0,
2670                              (void *)rej, sizeof *rej);
2671
2672 out:
2673         kfree(rep_param);
2674         kfree(rsp);
2675         kfree(rej);
2676
2677         return ret;
2678 }
2679
2680 static void srpt_cm_rej_recv(struct ib_cm_id *cm_id)
2681 {
2682         printk(KERN_INFO "Received IB REJ for cm_id %p.\n", cm_id);
2683         srpt_drain_channel(cm_id);
2684 }
2685
2686 /**
2687  * srpt_cm_rtu_recv() - Process an IB_CM_RTU_RECEIVED or USER_ESTABLISHED event.
2688  *
2689  * An IB_CM_RTU_RECEIVED message indicates that the connection is established
2690  * and that the recipient may begin transmitting (RTU = ready to use).
2691  */
2692 static void srpt_cm_rtu_recv(struct ib_cm_id *cm_id)
2693 {
2694         struct srpt_rdma_ch *ch;
2695         int ret;
2696
2697         ch = srpt_find_channel(cm_id->context, cm_id);
2698         BUG_ON(!ch);
2699
2700         if (srpt_test_and_set_ch_state(ch, CH_CONNECTING, CH_LIVE)) {
2701                 struct srpt_recv_ioctx *ioctx, *ioctx_tmp;
2702
2703                 ret = srpt_ch_qp_rts(ch, ch->qp);
2704
2705                 list_for_each_entry_safe(ioctx, ioctx_tmp, &ch->cmd_wait_list,
2706                                          wait_list) {
2707                         list_del(&ioctx->wait_list);
2708                         srpt_handle_new_iu(ch, ioctx, NULL);
2709                 }
2710                 if (ret)
2711                         srpt_close_ch(ch);
2712         }
2713 }
2714
2715 static void srpt_cm_timewait_exit(struct ib_cm_id *cm_id)
2716 {
2717         printk(KERN_INFO "Received IB TimeWait exit for cm_id %p.\n", cm_id);
2718         srpt_drain_channel(cm_id);
2719 }
2720
2721 static void srpt_cm_rep_error(struct ib_cm_id *cm_id)
2722 {
2723         printk(KERN_INFO "Received IB REP error for cm_id %p.\n", cm_id);
2724         srpt_drain_channel(cm_id);
2725 }
2726
2727 /**
2728  * srpt_cm_dreq_recv() - Process reception of a DREQ message.
2729  */
2730 static void srpt_cm_dreq_recv(struct ib_cm_id *cm_id)
2731 {
2732         struct srpt_rdma_ch *ch;
2733         unsigned long flags;
2734         bool send_drep = false;
2735
2736         ch = srpt_find_channel(cm_id->context, cm_id);
2737         BUG_ON(!ch);
2738
2739         pr_debug("cm_id= %p ch->state= %d\n", cm_id, srpt_get_ch_state(ch));
2740
2741         spin_lock_irqsave(&ch->spinlock, flags);
2742         switch (ch->state) {
2743         case CH_CONNECTING:
2744         case CH_LIVE:
2745                 send_drep = true;
2746                 ch->state = CH_DISCONNECTING;
2747                 break;
2748         case CH_DISCONNECTING:
2749         case CH_DRAINING:
2750         case CH_RELEASING:
2751                 WARN(true, "unexpected channel state %d\n", ch->state);
2752                 break;
2753         }
2754         spin_unlock_irqrestore(&ch->spinlock, flags);
2755
2756         if (send_drep) {
2757                 if (ib_send_cm_drep(ch->cm_id, NULL, 0) < 0)
2758                         printk(KERN_ERR "Sending IB DREP failed.\n");
2759                 printk(KERN_INFO "Received DREQ and sent DREP for session %s.\n",
2760                        ch->sess_name);
2761         }
2762 }
2763
2764 /**
2765  * srpt_cm_drep_recv() - Process reception of a DREP message.
2766  */
2767 static void srpt_cm_drep_recv(struct ib_cm_id *cm_id)
2768 {
2769         printk(KERN_INFO "Received InfiniBand DREP message for cm_id %p.\n",
2770                cm_id);
2771         srpt_drain_channel(cm_id);
2772 }
2773
2774 /**
2775  * srpt_cm_handler() - IB connection manager callback function.
2776  *
2777  * A non-zero return value will cause the caller destroy the CM ID.
2778  *
2779  * Note: srpt_cm_handler() must only return a non-zero value when transferring
2780  * ownership of the cm_id to a channel by srpt_cm_req_recv() failed. Returning
2781  * a non-zero value in any other case will trigger a race with the
2782  * ib_destroy_cm_id() call in srpt_release_channel().
2783  */
2784 static int srpt_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
2785 {
2786         int ret;
2787
2788         ret = 0;
2789         switch (event->event) {
2790         case IB_CM_REQ_RECEIVED:
2791                 ret = srpt_cm_req_recv(cm_id, &event->param.req_rcvd,
2792                                        event->private_data);
2793                 break;
2794         case IB_CM_REJ_RECEIVED:
2795                 srpt_cm_rej_recv(cm_id);
2796                 break;
2797         case IB_CM_RTU_RECEIVED:
2798         case IB_CM_USER_ESTABLISHED:
2799                 srpt_cm_rtu_recv(cm_id);
2800                 break;
2801         case IB_CM_DREQ_RECEIVED:
2802                 srpt_cm_dreq_recv(cm_id);
2803                 break;
2804         case IB_CM_DREP_RECEIVED:
2805                 srpt_cm_drep_recv(cm_id);
2806                 break;
2807         case IB_CM_TIMEWAIT_EXIT:
2808                 srpt_cm_timewait_exit(cm_id);
2809                 break;
2810         case IB_CM_REP_ERROR:
2811                 srpt_cm_rep_error(cm_id);
2812                 break;
2813         case IB_CM_DREQ_ERROR:
2814                 printk(KERN_INFO "Received IB DREQ ERROR event.\n");
2815                 break;
2816         case IB_CM_MRA_RECEIVED:
2817                 printk(KERN_INFO "Received IB MRA event\n");
2818                 break;
2819         default:
2820                 printk(KERN_ERR "received unrecognized IB CM event %d\n",
2821                        event->event);
2822                 break;
2823         }
2824
2825         return ret;
2826 }
2827
2828 /**
2829  * srpt_perform_rdmas() - Perform IB RDMA.
2830  *
2831  * Returns zero upon success or a negative number upon failure.
2832  */
2833 static int srpt_perform_rdmas(struct srpt_rdma_ch *ch,
2834                               struct srpt_send_ioctx *ioctx)
2835 {
2836         struct ib_send_wr wr;
2837         struct ib_send_wr *bad_wr;
2838         struct rdma_iu *riu;
2839         int i;
2840         int ret;
2841         int sq_wr_avail;
2842         enum dma_data_direction dir;
2843         const int n_rdma = ioctx->n_rdma;
2844
2845         dir = ioctx->cmd.data_direction;
2846         if (dir == DMA_TO_DEVICE) {
2847                 /* write */
2848                 ret = -ENOMEM;
2849                 sq_wr_avail = atomic_sub_return(n_rdma, &ch->sq_wr_avail);
2850                 if (sq_wr_avail < 0) {
2851                         printk(KERN_WARNING "IB send queue full (needed %d)\n",
2852                                n_rdma);
2853                         goto out;
2854                 }
2855         }
2856
2857         ioctx->rdma_aborted = false;
2858         ret = 0;
2859         riu = ioctx->rdma_ius;
2860         memset(&wr, 0, sizeof wr);
2861
2862         for (i = 0; i < n_rdma; ++i, ++riu) {
2863                 if (dir == DMA_FROM_DEVICE) {
2864                         wr.opcode = IB_WR_RDMA_WRITE;
2865                         wr.wr_id = encode_wr_id(i == n_rdma - 1 ?
2866                                                 SRPT_RDMA_WRITE_LAST :
2867                                                 SRPT_RDMA_MID,
2868                                                 ioctx->ioctx.index);
2869                 } else {
2870                         wr.opcode = IB_WR_RDMA_READ;
2871                         wr.wr_id = encode_wr_id(i == n_rdma - 1 ?
2872                                                 SRPT_RDMA_READ_LAST :
2873                                                 SRPT_RDMA_MID,
2874                                                 ioctx->ioctx.index);
2875                 }
2876                 wr.next = NULL;
2877                 wr.wr.rdma.remote_addr = riu->raddr;
2878                 wr.wr.rdma.rkey = riu->rkey;
2879                 wr.num_sge = riu->sge_cnt;
2880                 wr.sg_list = riu->sge;
2881
2882                 /* only get completion event for the last rdma write */
2883                 if (i == (n_rdma - 1) && dir == DMA_TO_DEVICE)
2884                         wr.send_flags = IB_SEND_SIGNALED;
2885
2886                 ret = ib_post_send(ch->qp, &wr, &bad_wr);
2887                 if (ret)
2888                         break;
2889         }
2890
2891         if (ret)
2892                 printk(KERN_ERR "%s[%d]: ib_post_send() returned %d for %d/%d",
2893                                  __func__, __LINE__, ret, i, n_rdma);
2894         if (ret && i > 0) {
2895                 wr.num_sge = 0;
2896                 wr.wr_id = encode_wr_id(SRPT_RDMA_ABORT, ioctx->ioctx.index);
2897                 wr.send_flags = IB_SEND_SIGNALED;
2898                 while (ch->state == CH_LIVE &&
2899                         ib_post_send(ch->qp, &wr, &bad_wr) != 0) {
2900                         printk(KERN_INFO "Trying to abort failed RDMA transfer [%d]",
2901                                 ioctx->ioctx.index);
2902                         msleep(1000);
2903                 }
2904                 while (ch->state != CH_RELEASING && !ioctx->rdma_aborted) {
2905                         printk(KERN_INFO "Waiting until RDMA abort finished [%d]",
2906                                 ioctx->ioctx.index);
2907                         msleep(1000);
2908                 }
2909         }
2910 out:
2911         if (unlikely(dir == DMA_TO_DEVICE && ret < 0))
2912                 atomic_add(n_rdma, &ch->sq_wr_avail);
2913         return ret;
2914 }
2915
2916 /**
2917  * srpt_xfer_data() - Start data transfer from initiator to target.
2918  */
2919 static int srpt_xfer_data(struct srpt_rdma_ch *ch,
2920                           struct srpt_send_ioctx *ioctx)
2921 {
2922         int ret;
2923
2924         ret = srpt_map_sg_to_ib_sge(ch, ioctx);
2925         if (ret) {
2926                 printk(KERN_ERR "%s[%d] ret=%d\n", __func__, __LINE__, ret);
2927                 goto out;
2928         }
2929
2930         ret = srpt_perform_rdmas(ch, ioctx);
2931         if (ret) {
2932                 if (ret == -EAGAIN || ret == -ENOMEM)
2933                         printk(KERN_INFO "%s[%d] queue full -- ret=%d\n",
2934                                    __func__, __LINE__, ret);
2935                 else
2936                         printk(KERN_ERR "%s[%d] fatal error -- ret=%d\n",
2937                                __func__, __LINE__, ret);
2938                 goto out_unmap;
2939         }
2940
2941 out:
2942         return ret;
2943 out_unmap:
2944         srpt_unmap_sg_to_ib_sge(ch, ioctx);
2945         goto out;
2946 }
2947
2948 static int srpt_write_pending_status(struct se_cmd *se_cmd)
2949 {
2950         struct srpt_send_ioctx *ioctx;
2951
2952         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
2953         return srpt_get_cmd_state(ioctx) == SRPT_STATE_NEED_DATA;
2954 }
2955
2956 /*
2957  * srpt_write_pending() - Start data transfer from initiator to target (write).
2958  */
2959 static int srpt_write_pending(struct se_cmd *se_cmd)
2960 {
2961         struct srpt_rdma_ch *ch;
2962         struct srpt_send_ioctx *ioctx;
2963         enum srpt_command_state new_state;
2964         enum rdma_ch_state ch_state;
2965         int ret;
2966
2967         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
2968
2969         new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA);
2970         WARN_ON(new_state == SRPT_STATE_DONE);
2971
2972         ch = ioctx->ch;
2973         BUG_ON(!ch);
2974
2975         ch_state = srpt_get_ch_state(ch);
2976         switch (ch_state) {
2977         case CH_CONNECTING:
2978                 WARN(true, "unexpected channel state %d\n", ch_state);
2979                 ret = -EINVAL;
2980                 goto out;
2981         case CH_LIVE:
2982                 break;
2983         case CH_DISCONNECTING:
2984         case CH_DRAINING:
2985         case CH_RELEASING:
2986                 pr_debug("cmd with tag %lld: channel disconnecting\n",
2987                          ioctx->tag);
2988                 srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN);
2989                 ret = -EINVAL;
2990                 goto out;
2991         }
2992         ret = srpt_xfer_data(ch, ioctx);
2993
2994 out:
2995         return ret;
2996 }
2997
2998 static u8 tcm_to_srp_tsk_mgmt_status(const int tcm_mgmt_status)
2999 {
3000         switch (tcm_mgmt_status) {
3001         case TMR_FUNCTION_COMPLETE:
3002                 return SRP_TSK_MGMT_SUCCESS;
3003         case TMR_FUNCTION_REJECTED:
3004                 return SRP_TSK_MGMT_FUNC_NOT_SUPP;
3005         }
3006         return SRP_TSK_MGMT_FAILED;
3007 }
3008
3009 /**
3010  * srpt_queue_response() - Transmits the response to a SCSI command.
3011  *
3012  * Callback function called by the TCM core. Must not block since it can be
3013  * invoked on the context of the IB completion handler.
3014  */
3015 static void srpt_queue_response(struct se_cmd *cmd)
3016 {
3017         struct srpt_rdma_ch *ch;
3018         struct srpt_send_ioctx *ioctx;
3019         enum srpt_command_state state;
3020         unsigned long flags;
3021         int ret;
3022         enum dma_data_direction dir;
3023         int resp_len;
3024         u8 srp_tm_status;
3025
3026         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
3027         ch = ioctx->ch;
3028         BUG_ON(!ch);
3029
3030         spin_lock_irqsave(&ioctx->spinlock, flags);
3031         state = ioctx->state;
3032         switch (state) {
3033         case SRPT_STATE_NEW:
3034         case SRPT_STATE_DATA_IN:
3035                 ioctx->state = SRPT_STATE_CMD_RSP_SENT;
3036                 break;
3037         case SRPT_STATE_MGMT:
3038                 ioctx->state = SRPT_STATE_MGMT_RSP_SENT;
3039                 break;
3040         default:
3041                 WARN(true, "ch %p; cmd %d: unexpected command state %d\n",
3042                         ch, ioctx->ioctx.index, ioctx->state);
3043                 break;
3044         }
3045         spin_unlock_irqrestore(&ioctx->spinlock, flags);
3046
3047         if (unlikely(transport_check_aborted_status(&ioctx->cmd, false)
3048                      || WARN_ON_ONCE(state == SRPT_STATE_CMD_RSP_SENT))) {
3049                 atomic_inc(&ch->req_lim_delta);
3050                 srpt_abort_cmd(ioctx);
3051                 return;
3052         }
3053
3054         dir = ioctx->cmd.data_direction;
3055
3056         /* For read commands, transfer the data to the initiator. */
3057         if (dir == DMA_FROM_DEVICE && ioctx->cmd.data_length &&
3058             !ioctx->queue_status_only) {
3059                 ret = srpt_xfer_data(ch, ioctx);
3060                 if (ret) {
3061                         printk(KERN_ERR "xfer_data failed for tag %llu\n",
3062                                ioctx->tag);
3063                         return;
3064                 }
3065         }
3066
3067         if (state != SRPT_STATE_MGMT)
3068                 resp_len = srpt_build_cmd_rsp(ch, ioctx, ioctx->tag,
3069                                               cmd->scsi_status);
3070         else {
3071                 srp_tm_status
3072                         = tcm_to_srp_tsk_mgmt_status(cmd->se_tmr_req->response);
3073                 resp_len = srpt_build_tskmgmt_rsp(ch, ioctx, srp_tm_status,
3074                                                  ioctx->tag);
3075         }
3076         ret = srpt_post_send(ch, ioctx, resp_len);
3077         if (ret) {
3078                 printk(KERN_ERR "sending cmd response failed for tag %llu\n",
3079                        ioctx->tag);
3080                 srpt_unmap_sg_to_ib_sge(ch, ioctx);
3081                 srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
3082                 target_put_sess_cmd(ioctx->ch->sess, &ioctx->cmd);
3083         }
3084 }
3085
3086 static int srpt_queue_data_in(struct se_cmd *cmd)
3087 {
3088         srpt_queue_response(cmd);
3089         return 0;
3090 }
3091
3092 static void srpt_queue_tm_rsp(struct se_cmd *cmd)
3093 {
3094         srpt_queue_response(cmd);
3095 }
3096
3097 static void srpt_aborted_task(struct se_cmd *cmd)
3098 {
3099         struct srpt_send_ioctx *ioctx = container_of(cmd,
3100                                 struct srpt_send_ioctx, cmd);
3101
3102         srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx);
3103 }
3104
3105 static int srpt_queue_status(struct se_cmd *cmd)
3106 {
3107         struct srpt_send_ioctx *ioctx;
3108
3109         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
3110         BUG_ON(ioctx->sense_data != cmd->sense_buffer);
3111         if (cmd->se_cmd_flags &
3112             (SCF_TRANSPORT_TASK_SENSE | SCF_EMULATED_TASK_SENSE))
3113                 WARN_ON(cmd->scsi_status != SAM_STAT_CHECK_CONDITION);
3114         ioctx->queue_status_only = true;
3115         srpt_queue_response(cmd);
3116         return 0;
3117 }
3118
3119 static void srpt_refresh_port_work(struct work_struct *work)
3120 {
3121         struct srpt_port *sport = container_of(work, struct srpt_port, work);
3122
3123         srpt_refresh_port(sport);
3124 }
3125
3126 static int srpt_ch_list_empty(struct srpt_device *sdev)
3127 {
3128         int res;
3129
3130         spin_lock_irq(&sdev->spinlock);
3131         res = list_empty(&sdev->rch_list);
3132         spin_unlock_irq(&sdev->spinlock);
3133
3134         return res;
3135 }
3136
3137 /**
3138  * srpt_release_sdev() - Free the channel resources associated with a target.
3139  */
3140 static int srpt_release_sdev(struct srpt_device *sdev)
3141 {
3142         struct srpt_rdma_ch *ch, *tmp_ch;
3143         int res;
3144
3145         WARN_ON_ONCE(irqs_disabled());
3146
3147         BUG_ON(!sdev);
3148
3149         spin_lock_irq(&sdev->spinlock);
3150         list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list)
3151                 __srpt_close_ch(ch);
3152         spin_unlock_irq(&sdev->spinlock);
3153
3154         res = wait_event_interruptible(sdev->ch_releaseQ,
3155                                        srpt_ch_list_empty(sdev));
3156         if (res)
3157                 printk(KERN_ERR "%s: interrupted.\n", __func__);
3158
3159         return 0;
3160 }
3161
3162 static struct srpt_port *__srpt_lookup_port(const char *name)
3163 {
3164         struct ib_device *dev;
3165         struct srpt_device *sdev;
3166         struct srpt_port *sport;
3167         int i;
3168
3169         list_for_each_entry(sdev, &srpt_dev_list, list) {
3170                 dev = sdev->device;
3171                 if (!dev)
3172                         continue;
3173
3174                 for (i = 0; i < dev->phys_port_cnt; i++) {
3175                         sport = &sdev->port[i];
3176
3177                         if (!strcmp(sport->port_guid, name))
3178                                 return sport;
3179                 }
3180         }
3181
3182         return NULL;
3183 }
3184
3185 static struct srpt_port *srpt_lookup_port(const char *name)
3186 {
3187         struct srpt_port *sport;
3188
3189         spin_lock(&srpt_dev_lock);
3190         sport = __srpt_lookup_port(name);
3191         spin_unlock(&srpt_dev_lock);
3192
3193         return sport;
3194 }
3195
3196 /**
3197  * srpt_add_one() - Infiniband device addition callback function.
3198  */
3199 static void srpt_add_one(struct ib_device *device)
3200 {
3201         struct srpt_device *sdev;
3202         struct srpt_port *sport;
3203         struct ib_srq_init_attr srq_attr;
3204         int i;
3205
3206         pr_debug("device = %p, device->dma_ops = %p\n", device,
3207                  device->dma_ops);
3208
3209         sdev = kzalloc(sizeof *sdev, GFP_KERNEL);
3210         if (!sdev)
3211                 goto err;
3212
3213         sdev->device = device;
3214         INIT_LIST_HEAD(&sdev->rch_list);
3215         init_waitqueue_head(&sdev->ch_releaseQ);
3216         spin_lock_init(&sdev->spinlock);
3217
3218         if (ib_query_device(device, &sdev->dev_attr))
3219                 goto free_dev;
3220
3221         sdev->pd = ib_alloc_pd(device);
3222         if (IS_ERR(sdev->pd))
3223                 goto free_dev;
3224
3225         sdev->mr = ib_get_dma_mr(sdev->pd, IB_ACCESS_LOCAL_WRITE);
3226         if (IS_ERR(sdev->mr))
3227                 goto err_pd;
3228
3229         sdev->srq_size = min(srpt_srq_size, sdev->dev_attr.max_srq_wr);
3230
3231         srq_attr.event_handler = srpt_srq_event;
3232         srq_attr.srq_context = (void *)sdev;
3233         srq_attr.attr.max_wr = sdev->srq_size;
3234         srq_attr.attr.max_sge = 1;
3235         srq_attr.attr.srq_limit = 0;
3236         srq_attr.srq_type = IB_SRQT_BASIC;
3237
3238         sdev->srq = ib_create_srq(sdev->pd, &srq_attr);
3239         if (IS_ERR(sdev->srq))
3240                 goto err_mr;
3241
3242         pr_debug("%s: create SRQ #wr= %d max_allow=%d dev= %s\n",
3243                  __func__, sdev->srq_size, sdev->dev_attr.max_srq_wr,
3244                  device->name);
3245
3246         if (!srpt_service_guid)
3247                 srpt_service_guid = be64_to_cpu(device->node_guid);
3248
3249         sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev);
3250         if (IS_ERR(sdev->cm_id))
3251                 goto err_srq;
3252
3253         /* print out target login information */
3254         pr_debug("Target login info: id_ext=%016llx,ioc_guid=%016llx,"
3255                  "pkey=ffff,service_id=%016llx\n", srpt_service_guid,
3256                  srpt_service_guid, srpt_service_guid);
3257
3258         /*
3259          * We do not have a consistent service_id (ie. also id_ext of target_id)
3260          * to identify this target. We currently use the guid of the first HCA
3261          * in the system as service_id; therefore, the target_id will change
3262          * if this HCA is gone bad and replaced by different HCA
3263          */
3264         if (ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid), 0, NULL))
3265                 goto err_cm;
3266
3267         INIT_IB_EVENT_HANDLER(&sdev->event_handler, sdev->device,
3268                               srpt_event_handler);
3269         if (ib_register_event_handler(&sdev->event_handler))
3270                 goto err_cm;
3271
3272         sdev->ioctx_ring = (struct srpt_recv_ioctx **)
3273                 srpt_alloc_ioctx_ring(sdev, sdev->srq_size,
3274                                       sizeof(*sdev->ioctx_ring[0]),
3275                                       srp_max_req_size, DMA_FROM_DEVICE);
3276         if (!sdev->ioctx_ring)
3277                 goto err_event;
3278
3279         for (i = 0; i < sdev->srq_size; ++i)
3280                 srpt_post_recv(sdev, sdev->ioctx_ring[i]);
3281
3282         WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));
3283
3284         for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
3285                 sport = &sdev->port[i - 1];
3286                 sport->sdev = sdev;
3287                 sport->port = i;
3288                 sport->port_attrib.srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE;
3289                 sport->port_attrib.srp_max_rsp_size = DEFAULT_MAX_RSP_SIZE;
3290                 sport->port_attrib.srp_sq_size = DEF_SRPT_SQ_SIZE;
3291                 INIT_WORK(&sport->work, srpt_refresh_port_work);
3292                 INIT_LIST_HEAD(&sport->port_acl_list);
3293                 spin_lock_init(&sport->port_acl_lock);
3294
3295                 if (srpt_refresh_port(sport)) {
3296                         printk(KERN_ERR "MAD registration failed for %s-%d.\n",
3297                                srpt_sdev_name(sdev), i);
3298                         goto err_ring;
3299                 }
3300                 snprintf(sport->port_guid, sizeof(sport->port_guid),
3301                         "0x%016llx%016llx",
3302                         be64_to_cpu(sport->gid.global.subnet_prefix),
3303                         be64_to_cpu(sport->gid.global.interface_id));
3304         }
3305
3306         spin_lock(&srpt_dev_lock);
3307         list_add_tail(&sdev->list, &srpt_dev_list);
3308         spin_unlock(&srpt_dev_lock);
3309
3310 out:
3311         ib_set_client_data(device, &srpt_client, sdev);
3312         pr_debug("added %s.\n", device->name);
3313         return;
3314
3315 err_ring:
3316         srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
3317                              sdev->srq_size, srp_max_req_size,
3318                              DMA_FROM_DEVICE);
3319 err_event:
3320         ib_unregister_event_handler(&sdev->event_handler);
3321 err_cm:
3322         ib_destroy_cm_id(sdev->cm_id);
3323 err_srq:
3324         ib_destroy_srq(sdev->srq);
3325 err_mr:
3326         ib_dereg_mr(sdev->mr);
3327 err_pd:
3328         ib_dealloc_pd(sdev->pd);
3329 free_dev:
3330         kfree(sdev);
3331 err:
3332         sdev = NULL;
3333         printk(KERN_INFO "%s(%s) failed.\n", __func__, device->name);
3334         goto out;
3335 }
3336
3337 /**
3338  * srpt_remove_one() - InfiniBand device removal callback function.
3339  */
3340 static void srpt_remove_one(struct ib_device *device)
3341 {
3342         struct srpt_device *sdev;
3343         int i;
3344
3345         sdev = ib_get_client_data(device, &srpt_client);
3346         if (!sdev) {
3347                 printk(KERN_INFO "%s(%s): nothing to do.\n", __func__,
3348                        device->name);
3349                 return;
3350         }
3351
3352         srpt_unregister_mad_agent(sdev);
3353
3354         ib_unregister_event_handler(&sdev->event_handler);
3355
3356         /* Cancel any work queued by the just unregistered IB event handler. */
3357         for (i = 0; i < sdev->device->phys_port_cnt; i++)
3358                 cancel_work_sync(&sdev->port[i].work);
3359
3360         ib_destroy_cm_id(sdev->cm_id);
3361
3362         /*
3363          * Unregistering a target must happen after destroying sdev->cm_id
3364          * such that no new SRP_LOGIN_REQ information units can arrive while
3365          * destroying the target.
3366          */
3367         spin_lock(&srpt_dev_lock);
3368         list_del(&sdev->list);
3369         spin_unlock(&srpt_dev_lock);
3370         srpt_release_sdev(sdev);
3371
3372         ib_destroy_srq(sdev->srq);
3373         ib_dereg_mr(sdev->mr);
3374         ib_dealloc_pd(sdev->pd);
3375
3376         srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
3377                              sdev->srq_size, srp_max_req_size, DMA_FROM_DEVICE);
3378         sdev->ioctx_ring = NULL;
3379         kfree(sdev);
3380 }
3381
3382 static struct ib_client srpt_client = {
3383         .name = DRV_NAME,
3384         .add = srpt_add_one,
3385         .remove = srpt_remove_one
3386 };
3387
3388 static int srpt_check_true(struct se_portal_group *se_tpg)
3389 {
3390         return 1;
3391 }
3392
3393 static int srpt_check_false(struct se_portal_group *se_tpg)
3394 {
3395         return 0;
3396 }
3397
3398 static char *srpt_get_fabric_name(void)
3399 {
3400         return "srpt";
3401 }
3402
3403 static u8 srpt_get_fabric_proto_ident(struct se_portal_group *se_tpg)
3404 {
3405         return SCSI_TRANSPORTID_PROTOCOLID_SRP;
3406 }
3407
3408 static char *srpt_get_fabric_wwn(struct se_portal_group *tpg)
3409 {
3410         struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1);
3411
3412         return sport->port_guid;
3413 }
3414
3415 static u16 srpt_get_tag(struct se_portal_group *tpg)
3416 {
3417         return 1;
3418 }
3419
3420 static u32 srpt_get_default_depth(struct se_portal_group *se_tpg)
3421 {
3422         return 1;
3423 }
3424
3425 static u32 srpt_get_pr_transport_id(struct se_portal_group *se_tpg,
3426                                     struct se_node_acl *se_nacl,
3427                                     struct t10_pr_registration *pr_reg,
3428                                     int *format_code, unsigned char *buf)
3429 {
3430         struct srpt_node_acl *nacl;
3431         struct spc_rdma_transport_id *tr_id;
3432
3433         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3434         tr_id = (void *)buf;
3435         tr_id->protocol_identifier = SCSI_TRANSPORTID_PROTOCOLID_SRP;
3436         memcpy(tr_id->i_port_id, nacl->i_port_id, sizeof(tr_id->i_port_id));
3437         return sizeof(*tr_id);
3438 }
3439
3440 static u32 srpt_get_pr_transport_id_len(struct se_portal_group *se_tpg,
3441                                         struct se_node_acl *se_nacl,
3442                                         struct t10_pr_registration *pr_reg,
3443                                         int *format_code)
3444 {
3445         *format_code = 0;
3446         return sizeof(struct spc_rdma_transport_id);
3447 }
3448
3449 static char *srpt_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
3450                                             const char *buf, u32 *out_tid_len,
3451                                             char **port_nexus_ptr)
3452 {
3453         struct spc_rdma_transport_id *tr_id;
3454
3455         *port_nexus_ptr = NULL;
3456         *out_tid_len = sizeof(struct spc_rdma_transport_id);
3457         tr_id = (void *)buf;
3458         return (char *)tr_id->i_port_id;
3459 }
3460
3461 static struct se_node_acl *srpt_alloc_fabric_acl(struct se_portal_group *se_tpg)
3462 {
3463         struct srpt_node_acl *nacl;
3464
3465         nacl = kzalloc(sizeof(struct srpt_node_acl), GFP_KERNEL);
3466         if (!nacl) {
3467                 printk(KERN_ERR "Unable to allocate struct srpt_node_acl\n");
3468                 return NULL;
3469         }
3470
3471         return &nacl->nacl;
3472 }
3473
3474 static void srpt_release_fabric_acl(struct se_portal_group *se_tpg,
3475                                     struct se_node_acl *se_nacl)
3476 {
3477         struct srpt_node_acl *nacl;
3478
3479         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3480         kfree(nacl);
3481 }
3482
3483 static u32 srpt_tpg_get_inst_index(struct se_portal_group *se_tpg)
3484 {
3485         return 1;
3486 }
3487
3488 static void srpt_release_cmd(struct se_cmd *se_cmd)
3489 {
3490         struct srpt_send_ioctx *ioctx = container_of(se_cmd,
3491                                 struct srpt_send_ioctx, cmd);
3492         struct srpt_rdma_ch *ch = ioctx->ch;
3493         unsigned long flags;
3494
3495         WARN_ON(ioctx->state != SRPT_STATE_DONE);
3496         WARN_ON(ioctx->mapped_sg_count != 0);
3497
3498         if (ioctx->n_rbuf > 1) {
3499                 kfree(ioctx->rbufs);
3500                 ioctx->rbufs = NULL;
3501                 ioctx->n_rbuf = 0;
3502         }
3503
3504         spin_lock_irqsave(&ch->spinlock, flags);
3505         list_add(&ioctx->free_list, &ch->free_list);
3506         spin_unlock_irqrestore(&ch->spinlock, flags);
3507 }
3508
3509 /**
3510  * srpt_close_session() - Forcibly close a session.
3511  *
3512  * Callback function invoked by the TCM core to clean up sessions associated
3513  * with a node ACL when the user invokes
3514  * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3515  */
3516 static void srpt_close_session(struct se_session *se_sess)
3517 {
3518         DECLARE_COMPLETION_ONSTACK(release_done);
3519         struct srpt_rdma_ch *ch;
3520         struct srpt_device *sdev;
3521         int res;
3522
3523         ch = se_sess->fabric_sess_ptr;
3524         WARN_ON(ch->sess != se_sess);
3525
3526         pr_debug("ch %p state %d\n", ch, srpt_get_ch_state(ch));
3527
3528         sdev = ch->sport->sdev;
3529         spin_lock_irq(&sdev->spinlock);
3530         BUG_ON(ch->release_done);
3531         ch->release_done = &release_done;
3532         __srpt_close_ch(ch);
3533         spin_unlock_irq(&sdev->spinlock);
3534
3535         res = wait_for_completion_timeout(&release_done, 60 * HZ);
3536         WARN_ON(res <= 0);
3537 }
3538
3539 /**
3540  * srpt_sess_get_index() - Return the value of scsiAttIntrPortIndex (SCSI-MIB).
3541  *
3542  * A quote from RFC 4455 (SCSI-MIB) about this MIB object:
3543  * This object represents an arbitrary integer used to uniquely identify a
3544  * particular attached remote initiator port to a particular SCSI target port
3545  * within a particular SCSI target device within a particular SCSI instance.
3546  */
3547 static u32 srpt_sess_get_index(struct se_session *se_sess)
3548 {
3549         return 0;
3550 }
3551
3552 static void srpt_set_default_node_attrs(struct se_node_acl *nacl)
3553 {
3554 }
3555
3556 static u32 srpt_get_task_tag(struct se_cmd *se_cmd)
3557 {
3558         struct srpt_send_ioctx *ioctx;
3559
3560         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
3561         return ioctx->tag;
3562 }
3563
3564 /* Note: only used from inside debug printk's by the TCM core. */
3565 static int srpt_get_tcm_cmd_state(struct se_cmd *se_cmd)
3566 {
3567         struct srpt_send_ioctx *ioctx;
3568
3569         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
3570         return srpt_get_cmd_state(ioctx);
3571 }
3572
3573 /**
3574  * srpt_parse_i_port_id() - Parse an initiator port ID.
3575  * @name: ASCII representation of a 128-bit initiator port ID.
3576  * @i_port_id: Binary 128-bit port ID.
3577  */
3578 static int srpt_parse_i_port_id(u8 i_port_id[16], const char *name)
3579 {
3580         const char *p;
3581         unsigned len, count, leading_zero_bytes;
3582         int ret, rc;
3583
3584         p = name;
3585         if (strncasecmp(p, "0x", 2) == 0)
3586                 p += 2;
3587         ret = -EINVAL;
3588         len = strlen(p);
3589         if (len % 2)
3590                 goto out;
3591         count = min(len / 2, 16U);
3592         leading_zero_bytes = 16 - count;
3593         memset(i_port_id, 0, leading_zero_bytes);
3594         rc = hex2bin(i_port_id + leading_zero_bytes, p, count);
3595         if (rc < 0)
3596                 pr_debug("hex2bin failed for srpt_parse_i_port_id: %d\n", rc);
3597         ret = 0;
3598 out:
3599         return ret;
3600 }
3601
3602 /*
3603  * configfs callback function invoked for
3604  * mkdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3605  */
3606 static struct se_node_acl *srpt_make_nodeacl(struct se_portal_group *tpg,
3607                                              struct config_group *group,
3608                                              const char *name)
3609 {
3610         struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1);
3611         struct se_node_acl *se_nacl, *se_nacl_new;
3612         struct srpt_node_acl *nacl;
3613         int ret = 0;
3614         u32 nexus_depth = 1;
3615         u8 i_port_id[16];
3616
3617         if (srpt_parse_i_port_id(i_port_id, name) < 0) {
3618                 printk(KERN_ERR "invalid initiator port ID %s\n", name);
3619                 ret = -EINVAL;
3620                 goto err;
3621         }
3622
3623         se_nacl_new = srpt_alloc_fabric_acl(tpg);
3624         if (!se_nacl_new) {
3625                 ret = -ENOMEM;
3626                 goto err;
3627         }
3628         /*
3629          * nacl_new may be released by core_tpg_add_initiator_node_acl()
3630          * when converting a node ACL from demo mode to explict
3631          */
3632         se_nacl = core_tpg_add_initiator_node_acl(tpg, se_nacl_new, name,
3633                                                   nexus_depth);
3634         if (IS_ERR(se_nacl)) {
3635                 ret = PTR_ERR(se_nacl);
3636                 goto err;
3637         }
3638         /* Locate our struct srpt_node_acl and set sdev and i_port_id. */
3639         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3640         memcpy(&nacl->i_port_id[0], &i_port_id[0], 16);
3641         nacl->sport = sport;
3642
3643         spin_lock_irq(&sport->port_acl_lock);
3644         list_add_tail(&nacl->list, &sport->port_acl_list);
3645         spin_unlock_irq(&sport->port_acl_lock);
3646
3647         return se_nacl;
3648 err:
3649         return ERR_PTR(ret);
3650 }
3651
3652 /*
3653  * configfs callback function invoked for
3654  * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3655  */
3656 static void srpt_drop_nodeacl(struct se_node_acl *se_nacl)
3657 {
3658         struct srpt_node_acl *nacl;
3659         struct srpt_device *sdev;
3660         struct srpt_port *sport;
3661
3662         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3663         sport = nacl->sport;
3664         sdev = sport->sdev;
3665         spin_lock_irq(&sport->port_acl_lock);
3666         list_del(&nacl->list);
3667         spin_unlock_irq(&sport->port_acl_lock);
3668         core_tpg_del_initiator_node_acl(&sport->port_tpg_1, se_nacl, 1);
3669         srpt_release_fabric_acl(NULL, se_nacl);
3670 }
3671
3672 static ssize_t srpt_tpg_attrib_show_srp_max_rdma_size(
3673         struct se_portal_group *se_tpg,
3674         char *page)
3675 {
3676         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3677
3678         return sprintf(page, "%u\n", sport->port_attrib.srp_max_rdma_size);
3679 }
3680
3681 static ssize_t srpt_tpg_attrib_store_srp_max_rdma_size(
3682         struct se_portal_group *se_tpg,
3683         const char *page,
3684         size_t count)
3685 {
3686         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3687         unsigned long val;
3688         int ret;
3689
3690         ret = kstrtoul(page, 0, &val);
3691         if (ret < 0) {
3692                 pr_err("kstrtoul() failed with ret: %d\n", ret);
3693                 return -EINVAL;
3694         }
3695         if (val > MAX_SRPT_RDMA_SIZE) {
3696                 pr_err("val: %lu exceeds MAX_SRPT_RDMA_SIZE: %d\n", val,
3697                         MAX_SRPT_RDMA_SIZE);
3698                 return -EINVAL;
3699         }
3700         if (val < DEFAULT_MAX_RDMA_SIZE) {
3701                 pr_err("val: %lu smaller than DEFAULT_MAX_RDMA_SIZE: %d\n",
3702                         val, DEFAULT_MAX_RDMA_SIZE);
3703                 return -EINVAL;
3704         }
3705         sport->port_attrib.srp_max_rdma_size = val;
3706
3707         return count;
3708 }
3709
3710 TF_TPG_ATTRIB_ATTR(srpt, srp_max_rdma_size, S_IRUGO | S_IWUSR);
3711
3712 static ssize_t srpt_tpg_attrib_show_srp_max_rsp_size(
3713         struct se_portal_group *se_tpg,
3714         char *page)
3715 {
3716         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3717
3718         return sprintf(page, "%u\n", sport->port_attrib.srp_max_rsp_size);
3719 }
3720
3721 static ssize_t srpt_tpg_attrib_store_srp_max_rsp_size(
3722         struct se_portal_group *se_tpg,
3723         const char *page,
3724         size_t count)
3725 {
3726         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3727         unsigned long val;
3728         int ret;
3729
3730         ret = kstrtoul(page, 0, &val);
3731         if (ret < 0) {
3732                 pr_err("kstrtoul() failed with ret: %d\n", ret);
3733                 return -EINVAL;
3734         }
3735         if (val > MAX_SRPT_RSP_SIZE) {
3736                 pr_err("val: %lu exceeds MAX_SRPT_RSP_SIZE: %d\n", val,
3737                         MAX_SRPT_RSP_SIZE);
3738                 return -EINVAL;
3739         }
3740         if (val < MIN_MAX_RSP_SIZE) {
3741                 pr_err("val: %lu smaller than MIN_MAX_RSP_SIZE: %d\n", val,
3742                         MIN_MAX_RSP_SIZE);
3743                 return -EINVAL;
3744         }
3745         sport->port_attrib.srp_max_rsp_size = val;
3746
3747         return count;
3748 }
3749
3750 TF_TPG_ATTRIB_ATTR(srpt, srp_max_rsp_size, S_IRUGO | S_IWUSR);
3751
3752 static ssize_t srpt_tpg_attrib_show_srp_sq_size(
3753         struct se_portal_group *se_tpg,
3754         char *page)
3755 {
3756         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3757
3758         return sprintf(page, "%u\n", sport->port_attrib.srp_sq_size);
3759 }
3760
3761 static ssize_t srpt_tpg_attrib_store_srp_sq_size(
3762         struct se_portal_group *se_tpg,
3763         const char *page,
3764         size_t count)
3765 {
3766         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3767         unsigned long val;
3768         int ret;
3769
3770         ret = kstrtoul(page, 0, &val);
3771         if (ret < 0) {
3772                 pr_err("kstrtoul() failed with ret: %d\n", ret);
3773                 return -EINVAL;
3774         }
3775         if (val > MAX_SRPT_SRQ_SIZE) {
3776                 pr_err("val: %lu exceeds MAX_SRPT_SRQ_SIZE: %d\n", val,
3777                         MAX_SRPT_SRQ_SIZE);
3778                 return -EINVAL;
3779         }
3780         if (val < MIN_SRPT_SRQ_SIZE) {
3781                 pr_err("val: %lu smaller than MIN_SRPT_SRQ_SIZE: %d\n", val,
3782                         MIN_SRPT_SRQ_SIZE);
3783                 return -EINVAL;
3784         }
3785         sport->port_attrib.srp_sq_size = val;
3786
3787         return count;
3788 }
3789
3790 TF_TPG_ATTRIB_ATTR(srpt, srp_sq_size, S_IRUGO | S_IWUSR);
3791
3792 static struct configfs_attribute *srpt_tpg_attrib_attrs[] = {
3793         &srpt_tpg_attrib_srp_max_rdma_size.attr,
3794         &srpt_tpg_attrib_srp_max_rsp_size.attr,
3795         &srpt_tpg_attrib_srp_sq_size.attr,
3796         NULL,
3797 };
3798
3799 static ssize_t srpt_tpg_show_enable(
3800         struct se_portal_group *se_tpg,
3801         char *page)
3802 {
3803         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3804
3805         return snprintf(page, PAGE_SIZE, "%d\n", (sport->enabled) ? 1: 0);
3806 }
3807
3808 static ssize_t srpt_tpg_store_enable(
3809         struct se_portal_group *se_tpg,
3810         const char *page,
3811         size_t count)
3812 {
3813         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3814         unsigned long tmp;
3815         int ret;
3816
3817         ret = kstrtoul(page, 0, &tmp);
3818         if (ret < 0) {
3819                 printk(KERN_ERR "Unable to extract srpt_tpg_store_enable\n");
3820                 return -EINVAL;
3821         }
3822
3823         if ((tmp != 0) && (tmp != 1)) {
3824                 printk(KERN_ERR "Illegal value for srpt_tpg_store_enable: %lu\n", tmp);
3825                 return -EINVAL;
3826         }
3827         if (tmp == 1)
3828                 sport->enabled = true;
3829         else
3830                 sport->enabled = false;
3831
3832         return count;
3833 }
3834
3835 TF_TPG_BASE_ATTR(srpt, enable, S_IRUGO | S_IWUSR);
3836
3837 static struct configfs_attribute *srpt_tpg_attrs[] = {
3838         &srpt_tpg_enable.attr,
3839         NULL,
3840 };
3841
3842 /**
3843  * configfs callback invoked for
3844  * mkdir /sys/kernel/config/target/$driver/$port/$tpg
3845  */
3846 static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn,
3847                                              struct config_group *group,
3848                                              const char *name)
3849 {
3850         struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn);
3851         int res;
3852
3853         /* Initialize sport->port_wwn and sport->port_tpg_1 */
3854         res = core_tpg_register(&srpt_target->tf_ops, &sport->port_wwn,
3855                         &sport->port_tpg_1, sport, TRANSPORT_TPG_TYPE_NORMAL);
3856         if (res)
3857                 return ERR_PTR(res);
3858
3859         return &sport->port_tpg_1;
3860 }
3861
3862 /**
3863  * configfs callback invoked for
3864  * rmdir /sys/kernel/config/target/$driver/$port/$tpg
3865  */
3866 static void srpt_drop_tpg(struct se_portal_group *tpg)
3867 {
3868         struct srpt_port *sport = container_of(tpg,
3869                                 struct srpt_port, port_tpg_1);
3870
3871         sport->enabled = false;
3872         core_tpg_deregister(&sport->port_tpg_1);
3873 }
3874
3875 /**
3876  * configfs callback invoked for
3877  * mkdir /sys/kernel/config/target/$driver/$port
3878  */
3879 static struct se_wwn *srpt_make_tport(struct target_fabric_configfs *tf,
3880                                       struct config_group *group,
3881                                       const char *name)
3882 {
3883         struct srpt_port *sport;
3884         int ret;
3885
3886         sport = srpt_lookup_port(name);
3887         pr_debug("make_tport(%s)\n", name);
3888         ret = -EINVAL;
3889         if (!sport)
3890                 goto err;
3891
3892         return &sport->port_wwn;
3893
3894 err:
3895         return ERR_PTR(ret);
3896 }
3897
3898 /**
3899  * configfs callback invoked for
3900  * rmdir /sys/kernel/config/target/$driver/$port
3901  */
3902 static void srpt_drop_tport(struct se_wwn *wwn)
3903 {
3904         struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn);
3905
3906         pr_debug("drop_tport(%s\n", config_item_name(&sport->port_wwn.wwn_group.cg_item));
3907 }
3908
3909 static ssize_t srpt_wwn_show_attr_version(struct target_fabric_configfs *tf,
3910                                               char *buf)
3911 {
3912         return scnprintf(buf, PAGE_SIZE, "%s\n", DRV_VERSION);
3913 }
3914
3915 TF_WWN_ATTR_RO(srpt, version);
3916
3917 static struct configfs_attribute *srpt_wwn_attrs[] = {
3918         &srpt_wwn_version.attr,
3919         NULL,
3920 };
3921
3922 static struct target_core_fabric_ops srpt_template = {
3923         .get_fabric_name                = srpt_get_fabric_name,
3924         .get_fabric_proto_ident         = srpt_get_fabric_proto_ident,
3925         .tpg_get_wwn                    = srpt_get_fabric_wwn,
3926         .tpg_get_tag                    = srpt_get_tag,
3927         .tpg_get_default_depth          = srpt_get_default_depth,
3928         .tpg_get_pr_transport_id        = srpt_get_pr_transport_id,
3929         .tpg_get_pr_transport_id_len    = srpt_get_pr_transport_id_len,
3930         .tpg_parse_pr_out_transport_id  = srpt_parse_pr_out_transport_id,
3931         .tpg_check_demo_mode            = srpt_check_false,
3932         .tpg_check_demo_mode_cache      = srpt_check_true,
3933         .tpg_check_demo_mode_write_protect = srpt_check_true,
3934         .tpg_check_prod_mode_write_protect = srpt_check_false,
3935         .tpg_alloc_fabric_acl           = srpt_alloc_fabric_acl,
3936         .tpg_release_fabric_acl         = srpt_release_fabric_acl,
3937         .tpg_get_inst_index             = srpt_tpg_get_inst_index,
3938         .release_cmd                    = srpt_release_cmd,
3939         .check_stop_free                = srpt_check_stop_free,
3940         .shutdown_session               = srpt_shutdown_session,
3941         .close_session                  = srpt_close_session,
3942         .sess_get_index                 = srpt_sess_get_index,
3943         .sess_get_initiator_sid         = NULL,
3944         .write_pending                  = srpt_write_pending,
3945         .write_pending_status           = srpt_write_pending_status,
3946         .set_default_node_attributes    = srpt_set_default_node_attrs,
3947         .get_task_tag                   = srpt_get_task_tag,
3948         .get_cmd_state                  = srpt_get_tcm_cmd_state,
3949         .queue_data_in                  = srpt_queue_data_in,
3950         .queue_status                   = srpt_queue_status,
3951         .queue_tm_rsp                   = srpt_queue_tm_rsp,
3952         .aborted_task                   = srpt_aborted_task,
3953         /*
3954          * Setup function pointers for generic logic in
3955          * target_core_fabric_configfs.c
3956          */
3957         .fabric_make_wwn                = srpt_make_tport,
3958         .fabric_drop_wwn                = srpt_drop_tport,
3959         .fabric_make_tpg                = srpt_make_tpg,
3960         .fabric_drop_tpg                = srpt_drop_tpg,
3961         .fabric_post_link               = NULL,
3962         .fabric_pre_unlink              = NULL,
3963         .fabric_make_np                 = NULL,
3964         .fabric_drop_np                 = NULL,
3965         .fabric_make_nodeacl            = srpt_make_nodeacl,
3966         .fabric_drop_nodeacl            = srpt_drop_nodeacl,
3967 };
3968
3969 /**
3970  * srpt_init_module() - Kernel module initialization.
3971  *
3972  * Note: Since ib_register_client() registers callback functions, and since at
3973  * least one of these callback functions (srpt_add_one()) calls target core
3974  * functions, this driver must be registered with the target core before
3975  * ib_register_client() is called.
3976  */
3977 static int __init srpt_init_module(void)
3978 {
3979         int ret;
3980
3981         ret = -EINVAL;
3982         if (srp_max_req_size < MIN_MAX_REQ_SIZE) {
3983                 printk(KERN_ERR "invalid value %d for kernel module parameter"
3984                        " srp_max_req_size -- must be at least %d.\n",
3985                        srp_max_req_size, MIN_MAX_REQ_SIZE);
3986                 goto out;
3987         }
3988
3989         if (srpt_srq_size < MIN_SRPT_SRQ_SIZE
3990             || srpt_srq_size > MAX_SRPT_SRQ_SIZE) {
3991                 printk(KERN_ERR "invalid value %d for kernel module parameter"
3992                        " srpt_srq_size -- must be in the range [%d..%d].\n",
3993                        srpt_srq_size, MIN_SRPT_SRQ_SIZE, MAX_SRPT_SRQ_SIZE);
3994                 goto out;
3995         }
3996
3997         srpt_target = target_fabric_configfs_init(THIS_MODULE, "srpt");
3998         if (IS_ERR(srpt_target)) {
3999                 printk(KERN_ERR "couldn't register\n");
4000                 ret = PTR_ERR(srpt_target);
4001                 goto out;
4002         }
4003
4004         srpt_target->tf_ops = srpt_template;
4005
4006         /*
4007          * Set up default attribute lists.
4008          */
4009         srpt_target->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = srpt_wwn_attrs;
4010         srpt_target->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = srpt_tpg_attrs;
4011         srpt_target->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = srpt_tpg_attrib_attrs;
4012         srpt_target->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
4013         srpt_target->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
4014         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;
4015         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
4016         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
4017         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;
4018
4019         ret = target_fabric_configfs_register(srpt_target);
4020         if (ret < 0) {
4021                 printk(KERN_ERR "couldn't register\n");
4022                 goto out_free_target;
4023         }
4024
4025         ret = ib_register_client(&srpt_client);
4026         if (ret) {
4027                 printk(KERN_ERR "couldn't register IB client\n");
4028                 goto out_unregister_target;
4029         }
4030
4031         return 0;
4032
4033 out_unregister_target:
4034         target_fabric_configfs_deregister(srpt_target);
4035         srpt_target = NULL;
4036 out_free_target:
4037         if (srpt_target)
4038                 target_fabric_configfs_free(srpt_target);
4039 out:
4040         return ret;
4041 }
4042
4043 static void __exit srpt_cleanup_module(void)
4044 {
4045         ib_unregister_client(&srpt_client);
4046         target_fabric_configfs_deregister(srpt_target);
4047         srpt_target = NULL;
4048 }
4049
4050 module_init(srpt_init_module);
4051 module_exit(srpt_cleanup_module);