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                 /* Refresh port data asynchronously. */
 202                 if (event->element.port_num <= sdev->device->phys_port_cnt) {
 203                         sport = &sdev->port[event->element.port_num - 1];
 204                         if (!sport->lid && !sport->sm_lid)
 205                                 schedule_work(&sport->work);
 206                 }
 207                 break;
 208         default:
 209                 printk(KERN_ERR "received unrecognized IB event %d\n",
 210                        event->event);
 211                 break;
 212         }
 213 }
 214
 215 /**
 216  * srpt_srq_event() - SRQ event callback function.
 217  */
 218 static void srpt_srq_event(struct ib_event *event, void *ctx)
 219 {
 220         printk(KERN_INFO "SRQ event %d\n", event->event);
 221 }
 222
 223 /**
 224  * srpt_qp_event() - QP event callback function.
 225  */
 226 static void srpt_qp_event(struct ib_event *event, struct srpt_rdma_ch *ch)
 227 {
 228         pr_debug("QP event %d on cm_id=%p sess_name=%s state=%d\n",
 229                  event->event, ch->cm_id, ch->sess_name, srpt_get_ch_state(ch));
 230
 231         switch (event->event) {
 232         case IB_EVENT_COMM_EST:
 233                 ib_cm_notify(ch->cm_id, event->event);
 234                 break;
 235         case IB_EVENT_QP_LAST_WQE_REACHED:
 236                 if (srpt_test_and_set_ch_state(ch, CH_DRAINING,
 237                                                CH_RELEASING))
 238                         srpt_release_channel(ch);
 239                 else
 240                         pr_debug("%s: state %d - ignored LAST_WQE.\n",
 241                                  ch->sess_name, srpt_get_ch_state(ch));
 242                 break;
 243         default:
 244                 printk(KERN_ERR "received unrecognized IB QP event %d\n",
 245                        event->event);
 246                 break;
 247         }
 248 }
 249
 250 /**
 251  * srpt_set_ioc() - Helper function for initializing an IOUnitInfo structure.
 252  *
 253  * @slot: one-based slot number.
 254  * @value: four-bit value.
 255  *
 256  * Copies the lowest four bits of value in element slot of the array of four
 257  * bit elements called c_list (controller list). The index slot is one-based.
 258  */
 259 static void srpt_set_ioc(u8 *c_list, u32 slot, u8 value)
 260 {
 261         u16 id;
 262         u8 tmp;
 263
 264         id = (slot - 1) / 2;
 265         if (slot & 0x1) {
 266                 tmp = c_list[id] & 0xf;
 267                 c_list[id] = (value << 4) | tmp;
 268         } else {
 269                 tmp = c_list[id] & 0xf0;
 270                 c_list[id] = (value & 0xf) | tmp;
 271         }
 272 }
 273
 274 /**
 275  * srpt_get_class_port_info() - Copy ClassPortInfo to a management datagram.
 276  *
 277  * See also section 16.3.3.1 ClassPortInfo in the InfiniBand Architecture
 278  * Specification.
 279  */
 280 static void srpt_get_class_port_info(struct ib_dm_mad *mad)
 281 {
 282         struct ib_class_port_info *cif;
 283
 284         cif = (struct ib_class_port_info *)mad->data;
 285         memset(cif, 0, sizeof *cif);
 286         cif->base_version = 1;
 287         cif->class_version = 1;
 288         cif->resp_time_value = 20;
 289
 290         mad->mad_hdr.status = 0;
 291 }
 292
 293 /**
 294  * srpt_get_iou() - Write IOUnitInfo to a management datagram.
 295  *
 296  * See also section 16.3.3.3 IOUnitInfo in the InfiniBand Architecture
 297  * Specification. See also section B.7, table B.6 in the SRP r16a document.
 298  */
 299 static void srpt_get_iou(struct ib_dm_mad *mad)
 300 {
 301         struct ib_dm_iou_info *ioui;
 302         u8 slot;
 303         int i;
 304
 305         ioui = (struct ib_dm_iou_info *)mad->data;
 306         ioui->change_id = __constant_cpu_to_be16(1);
 307         ioui->max_controllers = 16;
 308
 309         /* set present for slot 1 and empty for the rest */
 310         srpt_set_ioc(ioui->controller_list, 1, 1);
 311         for (i = 1, slot = 2; i < 16; i++, slot++)
 312                 srpt_set_ioc(ioui->controller_list, slot, 0);
 313
 314         mad->mad_hdr.status = 0;
 315 }
 316
 317 /**
 318  * srpt_get_ioc() - Write IOControllerprofile to a management datagram.
 319  *
 320  * See also section 16.3.3.4 IOControllerProfile in the InfiniBand
 321  * Architecture Specification. See also section B.7, table B.7 in the SRP
 322  * r16a document.
 323  */
 324 static void srpt_get_ioc(struct srpt_port *sport, u32 slot,
 325                          struct ib_dm_mad *mad)
 326 {
 327         struct srpt_device *sdev = sport->sdev;
 328         struct ib_dm_ioc_profile *iocp;
 329
 330         iocp = (struct ib_dm_ioc_profile *)mad->data;
 331
 332         if (!slot || slot > 16) {
 333                 mad->mad_hdr.status
 334                         = __constant_cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);
 335                 return;
 336         }
 337
 338         if (slot > 2) {
 339                 mad->mad_hdr.status
 340                         = __constant_cpu_to_be16(DM_MAD_STATUS_NO_IOC);
 341                 return;
 342         }
 343
 344         memset(iocp, 0, sizeof *iocp);
 345         strcpy(iocp->id_string, SRPT_ID_STRING);
 346         iocp->guid = cpu_to_be64(srpt_service_guid);
 347         iocp->vendor_id = cpu_to_be32(sdev->dev_attr.vendor_id);
 348         iocp->device_id = cpu_to_be32(sdev->dev_attr.vendor_part_id);
 349         iocp->device_version = cpu_to_be16(sdev->dev_attr.hw_ver);
 350         iocp->subsys_vendor_id = cpu_to_be32(sdev->dev_attr.vendor_id);
 351         iocp->subsys_device_id = 0x0;
 352         iocp->io_class = __constant_cpu_to_be16(SRP_REV16A_IB_IO_CLASS);
 353         iocp->io_subclass = __constant_cpu_to_be16(SRP_IO_SUBCLASS);
 354         iocp->protocol = __constant_cpu_to_be16(SRP_PROTOCOL);
 355         iocp->protocol_version = __constant_cpu_to_be16(SRP_PROTOCOL_VERSION);
 356         iocp->send_queue_depth = cpu_to_be16(sdev->srq_size);
 357         iocp->rdma_read_depth = 4;
 358         iocp->send_size = cpu_to_be32(srp_max_req_size);
 359         iocp->rdma_size = cpu_to_be32(min(sport->port_attrib.srp_max_rdma_size,
 360                                           1U << 24));
 361         iocp->num_svc_entries = 1;
 362         iocp->op_cap_mask = SRP_SEND_TO_IOC | SRP_SEND_FROM_IOC |
 363                 SRP_RDMA_READ_FROM_IOC | SRP_RDMA_WRITE_FROM_IOC;
 364
 365         mad->mad_hdr.status = 0;
 366 }
 367
 368 /**
 369  * srpt_get_svc_entries() - Write ServiceEntries to a management datagram.
 370  *
 371  * See also section 16.3.3.5 ServiceEntries in the InfiniBand Architecture
 372  * Specification. See also section B.7, table B.8 in the SRP r16a document.
 373  */
 374 static void srpt_get_svc_entries(u64 ioc_guid,
 375                                  u16 slot, u8 hi, u8 lo, struct ib_dm_mad *mad)
 376 {
 377         struct ib_dm_svc_entries *svc_entries;
 378
 379         WARN_ON(!ioc_guid);
 380
 381         if (!slot || slot > 16) {
 382                 mad->mad_hdr.status
 383                         = __constant_cpu_to_be16(DM_MAD_STATUS_INVALID_FIELD);
 384                 return;
 385         }
 386
 387         if (slot > 2 || lo > hi || hi > 1) {
 388                 mad->mad_hdr.status
 389                         = __constant_cpu_to_be16(DM_MAD_STATUS_NO_IOC);
 390                 return;
 391         }
 392
 393         svc_entries = (struct ib_dm_svc_entries *)mad->data;
 394         memset(svc_entries, 0, sizeof *svc_entries);
 395         svc_entries->service_entries[0].id = cpu_to_be64(ioc_guid);
 396         snprintf(svc_entries->service_entries[0].name,
 397                  sizeof(svc_entries->service_entries[0].name),
 398                  "%s%016llx",
 399                  SRP_SERVICE_NAME_PREFIX,
 400                  ioc_guid);
 401
 402         mad->mad_hdr.status = 0;
 403 }
 404
 405 /**
 406  * srpt_mgmt_method_get() - Process a received management datagram.
 407  * @sp:      source port through which the MAD has been received.
 408  * @rq_mad:  received MAD.
 409  * @rsp_mad: response MAD.
 410  */
 411 static void srpt_mgmt_method_get(struct srpt_port *sp, struct ib_mad *rq_mad,
 412                                  struct ib_dm_mad *rsp_mad)
 413 {
 414         u16 attr_id;
 415         u32 slot;
 416         u8 hi, lo;
 417
 418         attr_id = be16_to_cpu(rq_mad->mad_hdr.attr_id);
 419         switch (attr_id) {
 420         case DM_ATTR_CLASS_PORT_INFO:
 421                 srpt_get_class_port_info(rsp_mad);
 422                 break;
 423         case DM_ATTR_IOU_INFO:
 424                 srpt_get_iou(rsp_mad);
 425                 break;
 426         case DM_ATTR_IOC_PROFILE:
 427                 slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);
 428                 srpt_get_ioc(sp, slot, rsp_mad);
 429                 break;
 430         case DM_ATTR_SVC_ENTRIES:
 431                 slot = be32_to_cpu(rq_mad->mad_hdr.attr_mod);
 432                 hi = (u8) ((slot >> 8) & 0xff);
 433                 lo = (u8) (slot & 0xff);
 434                 slot = (u16) ((slot >> 16) & 0xffff);
 435                 srpt_get_svc_entries(srpt_service_guid,
 436                                      slot, hi, lo, rsp_mad);
 437                 break;
 438         default:
 439                 rsp_mad->mad_hdr.status =
 440                     __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);
 441                 break;
 442         }
 443 }
 444
 445 /**
 446  * srpt_mad_send_handler() - Post MAD-send callback function.
 447  */
 448 static void srpt_mad_send_handler(struct ib_mad_agent *mad_agent,
 449                                   struct ib_mad_send_wc *mad_wc)
 450 {
 451         ib_destroy_ah(mad_wc->send_buf->ah);
 452         ib_free_send_mad(mad_wc->send_buf);
 453 }
 454
 455 /**
 456  * srpt_mad_recv_handler() - MAD reception callback function.
 457  */
 458 static void srpt_mad_recv_handler(struct ib_mad_agent *mad_agent,
 459                                   struct ib_mad_recv_wc *mad_wc)
 460 {
 461         struct srpt_port *sport = (struct srpt_port *)mad_agent->context;
 462         struct ib_ah *ah;
 463         struct ib_mad_send_buf *rsp;
 464         struct ib_dm_mad *dm_mad;
 465
 466         if (!mad_wc || !mad_wc->recv_buf.mad)
 467                 return;
 468
 469         ah = ib_create_ah_from_wc(mad_agent->qp->pd, mad_wc->wc,
 470                                   mad_wc->recv_buf.grh, mad_agent->port_num);
 471         if (IS_ERR(ah))
 472                 goto err;
 473
 474         BUILD_BUG_ON(offsetof(struct ib_dm_mad, data) != IB_MGMT_DEVICE_HDR);
 475
 476         rsp = ib_create_send_mad(mad_agent, mad_wc->wc->src_qp,
 477                                  mad_wc->wc->pkey_index, 0,
 478                                  IB_MGMT_DEVICE_HDR, IB_MGMT_DEVICE_DATA,
 479                                  GFP_KERNEL);
 480         if (IS_ERR(rsp))
 481                 goto err_rsp;
 482
 483         rsp->ah = ah;
 484
 485         dm_mad = rsp->mad;
 486         memcpy(dm_mad, mad_wc->recv_buf.mad, sizeof *dm_mad);
 487         dm_mad->mad_hdr.method = IB_MGMT_METHOD_GET_RESP;
 488         dm_mad->mad_hdr.status = 0;
 489
 490         switch (mad_wc->recv_buf.mad->mad_hdr.method) {
 491         case IB_MGMT_METHOD_GET:
 492                 srpt_mgmt_method_get(sport, mad_wc->recv_buf.mad, dm_mad);
 493                 break;
 494         case IB_MGMT_METHOD_SET:
 495                 dm_mad->mad_hdr.status =
 496                     __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD_ATTR);
 497                 break;
 498         default:
 499                 dm_mad->mad_hdr.status =
 500                     __constant_cpu_to_be16(DM_MAD_STATUS_UNSUP_METHOD);
 501                 break;
 502         }
 503
 504         if (!ib_post_send_mad(rsp, NULL)) {
 505                 ib_free_recv_mad(mad_wc);
 506                 /* will destroy_ah & free_send_mad in send completion */
 507                 return;
 508         }
 509
 510         ib_free_send_mad(rsp);
 511
 512 err_rsp:
 513         ib_destroy_ah(ah);
 514 err:
 515         ib_free_recv_mad(mad_wc);
 516 }
 517
 518 /**
 519  * srpt_refresh_port() - Configure a HCA port.
 520  *
 521  * Enable InfiniBand management datagram processing, update the cached sm_lid,
 522  * lid and gid values, and register a callback function for processing MADs
 523  * on the specified port.
 524  *
 525  * Note: It is safe to call this function more than once for the same port.
 526  */
 527 static int srpt_refresh_port(struct srpt_port *sport)
 528 {
 529         struct ib_mad_reg_req reg_req;
 530         struct ib_port_modify port_modify;
 531         struct ib_port_attr port_attr;
 532         int ret;
 533
 534         memset(&port_modify, 0, sizeof port_modify);
 535         port_modify.set_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;
 536         port_modify.clr_port_cap_mask = 0;
 537
 538         ret = ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify);
 539         if (ret)
 540                 goto err_mod_port;
 541
 542         ret = ib_query_port(sport->sdev->device, sport->port, &port_attr);
 543         if (ret)
 544                 goto err_query_port;
 545
 546         sport->sm_lid = port_attr.sm_lid;
 547         sport->lid = port_attr.lid;
 548
 549         ret = ib_query_gid(sport->sdev->device, sport->port, 0, &sport->gid);
 550         if (ret)
 551                 goto err_query_port;
 552
 553         if (!sport->mad_agent) {
 554                 memset(&reg_req, 0, sizeof reg_req);
 555                 reg_req.mgmt_class = IB_MGMT_CLASS_DEVICE_MGMT;
 556                 reg_req.mgmt_class_version = IB_MGMT_BASE_VERSION;
 557                 set_bit(IB_MGMT_METHOD_GET, reg_req.method_mask);
 558                 set_bit(IB_MGMT_METHOD_SET, reg_req.method_mask);
 559
 560                 sport->mad_agent = ib_register_mad_agent(sport->sdev->device,
 561                                                          sport->port,
 562                                                          IB_QPT_GSI,
 563                                                          &reg_req, 0,
 564                                                          srpt_mad_send_handler,
 565                                                          srpt_mad_recv_handler,
 566                                                          sport);
 567                 if (IS_ERR(sport->mad_agent)) {
 568                         ret = PTR_ERR(sport->mad_agent);
 569                         sport->mad_agent = NULL;
 570                         goto err_query_port;
 571                 }
 572         }
 573
 574         return 0;
 575
 576 err_query_port:
 577
 578         port_modify.set_port_cap_mask = 0;
 579         port_modify.clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP;
 580         ib_modify_port(sport->sdev->device, sport->port, 0, &port_modify);
 581
 582 err_mod_port:
 583
 584         return ret;
 585 }
 586
 587 /**
 588  * srpt_unregister_mad_agent() - Unregister MAD callback functions.
 589  *
 590  * Note: It is safe to call this function more than once for the same device.
 591  */
 592 static void srpt_unregister_mad_agent(struct srpt_device *sdev)
 593 {
 594         struct ib_port_modify port_modify = {
 595                 .clr_port_cap_mask = IB_PORT_DEVICE_MGMT_SUP,
 596         };
 597         struct srpt_port *sport;
 598         int i;
 599
 600         for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
 601                 sport = &sdev->port[i - 1];
 602                 WARN_ON(sport->port != i);
 603                 if (ib_modify_port(sdev->device, i, 0, &port_modify) < 0)
 604                         printk(KERN_ERR "disabling MAD processing failed.\n");
 605                 if (sport->mad_agent) {
 606                         ib_unregister_mad_agent(sport->mad_agent);
 607                         sport->mad_agent = NULL;
 608                 }
 609         }
 610 }
 611
 612 /**
 613  * srpt_alloc_ioctx() - Allocate an SRPT I/O context structure.
 614  */
 615 static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev,
 616                                            int ioctx_size, int dma_size,
 617                                            enum dma_data_direction dir)
 618 {
 619         struct srpt_ioctx *ioctx;
 620
 621         ioctx = kmalloc(ioctx_size, GFP_KERNEL);
 622         if (!ioctx)
 623                 goto err;
 624
 625         ioctx->buf = kmalloc(dma_size, GFP_KERNEL);
 626         if (!ioctx->buf)
 627                 goto err_free_ioctx;
 628
 629         ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf, dma_size, dir);
 630         if (ib_dma_mapping_error(sdev->device, ioctx->dma))
 631                 goto err_free_buf;
 632
 633         return ioctx;
 634
 635 err_free_buf:
 636         kfree(ioctx->buf);
 637 err_free_ioctx:
 638         kfree(ioctx);
 639 err:
 640         return NULL;
 641 }
 642
 643 /**
 644  * srpt_free_ioctx() - Free an SRPT I/O context structure.
 645  */
 646 static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx,
 647                             int dma_size, enum dma_data_direction dir)
 648 {
 649         if (!ioctx)
 650                 return;
 651
 652         ib_dma_unmap_single(sdev->device, ioctx->dma, dma_size, dir);
 653         kfree(ioctx->buf);
 654         kfree(ioctx);
 655 }
 656
 657 /**
 658  * srpt_alloc_ioctx_ring() - Allocate a ring of SRPT I/O context structures.
 659  * @sdev:       Device to allocate the I/O context ring for.
 660  * @ring_size:  Number of elements in the I/O context ring.
 661  * @ioctx_size: I/O context size.
 662  * @dma_size:   DMA buffer size.
 663  * @dir:        DMA data direction.
 664  */
 665 static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev,
 666                                 int ring_size, int ioctx_size,
 667                                 int dma_size, enum dma_data_direction dir)
 668 {
 669         struct srpt_ioctx **ring;
 670         int i;
 671
 672         WARN_ON(ioctx_size != sizeof(struct srpt_recv_ioctx)
 673                 && ioctx_size != sizeof(struct srpt_send_ioctx));
 674
 675         ring = kmalloc(ring_size * sizeof(ring[0]), GFP_KERNEL);
 676         if (!ring)
 677                 goto out;
 678         for (i = 0; i < ring_size; ++i) {
 679                 ring[i] = srpt_alloc_ioctx(sdev, ioctx_size, dma_size, dir);
 680                 if (!ring[i])
 681                         goto err;
 682                 ring[i]->index = i;
 683         }
 684         goto out;
 685
 686 err:
 687         while (--i >= 0)
 688                 srpt_free_ioctx(sdev, ring[i], dma_size, dir);
 689         kfree(ring);
 690         ring = NULL;
 691 out:
 692         return ring;
 693 }
 694
 695 /**
 696  * srpt_free_ioctx_ring() - Free the ring of SRPT I/O context structures.
 697  */
 698 static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring,
 699                                  struct srpt_device *sdev, int ring_size,
 700                                  int dma_size, enum dma_data_direction dir)
 701 {
 702         int i;
 703
 704         for (i = 0; i < ring_size; ++i)
 705                 srpt_free_ioctx(sdev, ioctx_ring[i], dma_size, dir);
 706         kfree(ioctx_ring);
 707 }
 708
 709 /**
 710  * srpt_get_cmd_state() - Get the state of a SCSI command.
 711  */
 712 static enum srpt_command_state srpt_get_cmd_state(struct srpt_send_ioctx *ioctx)
 713 {
 714         enum srpt_command_state state;
 715         unsigned long flags;
 716
 717         BUG_ON(!ioctx);
 718
 719         spin_lock_irqsave(&ioctx->spinlock, flags);
 720         state = ioctx->state;
 721         spin_unlock_irqrestore(&ioctx->spinlock, flags);
 722         return state;
 723 }
 724
 725 /**
 726  * srpt_set_cmd_state() - Set the state of a SCSI command.
 727  *
 728  * Does not modify the state of aborted commands. Returns the previous command
 729  * state.
 730  */
 731 static enum srpt_command_state srpt_set_cmd_state(struct srpt_send_ioctx *ioctx,
 732                                                   enum srpt_command_state new)
 733 {
 734         enum srpt_command_state previous;
 735         unsigned long flags;
 736
 737         BUG_ON(!ioctx);
 738
 739         spin_lock_irqsave(&ioctx->spinlock, flags);
 740         previous = ioctx->state;
 741         if (previous != SRPT_STATE_DONE)
 742                 ioctx->state = new;
 743         spin_unlock_irqrestore(&ioctx->spinlock, flags);
 744
 745         return previous;
 746 }
 747
 748 /**
 749  * srpt_test_and_set_cmd_state() - Test and set the state of a command.
 750  *
 751  * Returns true if and only if the previous command state was equal to 'old'.
 752  */
 753 static bool srpt_test_and_set_cmd_state(struct srpt_send_ioctx *ioctx,
 754                                         enum srpt_command_state old,
 755                                         enum srpt_command_state new)
 756 {
 757         enum srpt_command_state previous;
 758         unsigned long flags;
 759
 760         WARN_ON(!ioctx);
 761         WARN_ON(old == SRPT_STATE_DONE);
 762         WARN_ON(new == SRPT_STATE_NEW);
 763
 764         spin_lock_irqsave(&ioctx->spinlock, flags);
 765         previous = ioctx->state;
 766         if (previous == old)
 767                 ioctx->state = new;
 768         spin_unlock_irqrestore(&ioctx->spinlock, flags);
 769         return previous == old;
 770 }
 771
 772 /**
 773  * srpt_post_recv() - Post an IB receive request.
 774  */
 775 static int srpt_post_recv(struct srpt_device *sdev,
 776                           struct srpt_recv_ioctx *ioctx)
 777 {
 778         struct ib_sge list;
 779         struct ib_recv_wr wr, *bad_wr;
 780
 781         BUG_ON(!sdev);
 782         wr.wr_id = encode_wr_id(SRPT_RECV, ioctx->ioctx.index);
 783
 784         list.addr = ioctx->ioctx.dma;
 785         list.length = srp_max_req_size;
 786         list.lkey = sdev->mr->lkey;
 787
 788         wr.next = NULL;
 789         wr.sg_list = &list;
 790         wr.num_sge = 1;
 791
 792         return ib_post_srq_recv(sdev->srq, &wr, &bad_wr);
 793 }
 794
 795 /**
 796  * srpt_post_send() - Post an IB send request.
 797  *
 798  * Returns zero upon success and a non-zero value upon failure.
 799  */
 800 static int srpt_post_send(struct srpt_rdma_ch *ch,
 801                           struct srpt_send_ioctx *ioctx, int len)
 802 {
 803         struct ib_sge list;
 804         struct ib_send_wr wr, *bad_wr;
 805         struct srpt_device *sdev = ch->sport->sdev;
 806         int ret;
 807
 808         atomic_inc(&ch->req_lim);
 809
 810         ret = -ENOMEM;
 811         if (unlikely(atomic_dec_return(&ch->sq_wr_avail) < 0)) {
 812                 printk(KERN_WARNING "IB send queue full (needed 1)\n");
 813                 goto out;
 814         }
 815
 816         ib_dma_sync_single_for_device(sdev->device, ioctx->ioctx.dma, len,
 817                                       DMA_TO_DEVICE);
 818
 819         list.addr = ioctx->ioctx.dma;
 820         list.length = len;
 821         list.lkey = sdev->mr->lkey;
 822
 823         wr.next = NULL;
 824         wr.wr_id = encode_wr_id(SRPT_SEND, ioctx->ioctx.index);
 825         wr.sg_list = &list;
 826         wr.num_sge = 1;
 827         wr.opcode = IB_WR_SEND;
 828         wr.send_flags = IB_SEND_SIGNALED;
 829
 830         ret = ib_post_send(ch->qp, &wr, &bad_wr);
 831
 832 out:
 833         if (ret < 0) {
 834                 atomic_inc(&ch->sq_wr_avail);
 835                 atomic_dec(&ch->req_lim);
 836         }
 837         return ret;
 838 }
 839
 840 /**
 841  * srpt_get_desc_tbl() - Parse the data descriptors of an SRP_CMD request.
 842  * @ioctx: Pointer to the I/O context associated with the request.
 843  * @srp_cmd: Pointer to the SRP_CMD request data.
 844  * @dir: Pointer to the variable to which the transfer direction will be
 845  *   written.
 846  * @data_len: Pointer to the variable to which the total data length of all
 847  *   descriptors in the SRP_CMD request will be written.
 848  *
 849  * This function initializes ioctx->nrbuf and ioctx->r_bufs.
 850  *
 851  * Returns -EINVAL when the SRP_CMD request contains inconsistent descriptors;
 852  * -ENOMEM when memory allocation fails and zero upon success.
 853  */
 854 static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
 855                              struct srp_cmd *srp_cmd,
 856                              enum dma_data_direction *dir, u64 *data_len)
 857 {
 858         struct srp_indirect_buf *idb;
 859         struct srp_direct_buf *db;
 860         unsigned add_cdb_offset;
 861         int ret;
 862
 863         /*
 864          * The pointer computations below will only be compiled correctly
 865          * if srp_cmd::add_data is declared as s8*, u8*, s8[] or u8[], so check
 866          * whether srp_cmd::add_data has been declared as a byte pointer.
 867          */
 868         BUILD_BUG_ON(!__same_type(srp_cmd->add_data[0], (s8)0)
 869                      && !__same_type(srp_cmd->add_data[0], (u8)0));
 870
 871         BUG_ON(!dir);
 872         BUG_ON(!data_len);
 873
 874         ret = 0;
 875         *data_len = 0;
 876
 877         /*
 878          * The lower four bits of the buffer format field contain the DATA-IN
 879          * buffer descriptor format, and the highest four bits contain the
 880          * DATA-OUT buffer descriptor format.
 881          */
 882         *dir = DMA_NONE;
 883         if (srp_cmd->buf_fmt & 0xf)
 884                 /* DATA-IN: transfer data from target to initiator (read). */
 885                 *dir = DMA_FROM_DEVICE;
 886         else if (srp_cmd->buf_fmt >> 4)
 887                 /* DATA-OUT: transfer data from initiator to target (write). */
 888                 *dir = DMA_TO_DEVICE;
 889
 890         /*
 891          * According to the SRP spec, the lower two bits of the 'ADDITIONAL
 892          * CDB LENGTH' field are reserved and the size in bytes of this field
 893          * is four times the value specified in bits 3..7. Hence the "& ~3".
 894          */
 895         add_cdb_offset = srp_cmd->add_cdb_len & ~3;
 896         if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) ||
 897             ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) {
 898                 ioctx->n_rbuf = 1;
 899                 ioctx->rbufs = &ioctx->single_rbuf;
 900
 901                 db = (struct srp_direct_buf *)(srp_cmd->add_data
 902                                                + add_cdb_offset);
 903                 memcpy(ioctx->rbufs, db, sizeof *db);
 904                 *data_len = be32_to_cpu(db->len);
 905         } else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) ||
 906                    ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) {
 907                 idb = (struct srp_indirect_buf *)(srp_cmd->add_data
 908                                                   + add_cdb_offset);
 909
 910                 ioctx->n_rbuf = be32_to_cpu(idb->table_desc.len) / sizeof *db;
 911
 912                 if (ioctx->n_rbuf >
 913                     (srp_cmd->data_out_desc_cnt + srp_cmd->data_in_desc_cnt)) {
 914                         printk(KERN_ERR "received unsupported SRP_CMD request"
 915                                " type (%u out + %u in != %u / %zu)\n",
 916                                srp_cmd->data_out_desc_cnt,
 917                                srp_cmd->data_in_desc_cnt,
 918                                be32_to_cpu(idb->table_desc.len),
 919                                sizeof(*db));
 920                         ioctx->n_rbuf = 0;
 921                         ret = -EINVAL;
 922                         goto out;
 923                 }
 924
 925                 if (ioctx->n_rbuf == 1)
 926                         ioctx->rbufs = &ioctx->single_rbuf;
 927                 else {
 928                         ioctx->rbufs =
 929                                 kmalloc(ioctx->n_rbuf * sizeof *db, GFP_ATOMIC);
 930                         if (!ioctx->rbufs) {
 931                                 ioctx->n_rbuf = 0;
 932                                 ret = -ENOMEM;
 933                                 goto out;
 934                         }
 935                 }
 936
 937                 db = idb->desc_list;
 938                 memcpy(ioctx->rbufs, db, ioctx->n_rbuf * sizeof *db);
 939                 *data_len = be32_to_cpu(idb->len);
 940         }
 941 out:
 942         return ret;
 943 }
 944
 945 /**
 946  * srpt_init_ch_qp() - Initialize queue pair attributes.
 947  *
 948  * Initialized the attributes of queue pair 'qp' by allowing local write,
 949  * remote read and remote write. Also transitions 'qp' to state IB_QPS_INIT.
 950  */
 951 static int srpt_init_ch_qp(struct srpt_rdma_ch *ch, struct ib_qp *qp)
 952 {
 953         struct ib_qp_attr *attr;
 954         int ret;
 955
 956         attr = kzalloc(sizeof *attr, GFP_KERNEL);
 957         if (!attr)
 958                 return -ENOMEM;
 959
 960         attr->qp_state = IB_QPS_INIT;
 961         attr->qp_access_flags = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_READ |
 962             IB_ACCESS_REMOTE_WRITE;
 963         attr->port_num = ch->sport->port;
 964         attr->pkey_index = 0;
 965
 966         ret = ib_modify_qp(qp, attr,
 967                            IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PORT |
 968                            IB_QP_PKEY_INDEX);
 969
 970         kfree(attr);
 971         return ret;
 972 }
 973
 974 /**
 975  * srpt_ch_qp_rtr() - Change the state of a channel to 'ready to receive' (RTR).
 976  * @ch: channel of the queue pair.
 977  * @qp: queue pair to change the state of.
 978  *
 979  * Returns zero upon success and a negative value upon failure.
 980  *
 981  * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system.
 982  * If this structure ever becomes larger, it might be necessary to allocate
 983  * it dynamically instead of on the stack.
 984  */
 985 static int srpt_ch_qp_rtr(struct srpt_rdma_ch *ch, struct ib_qp *qp)
 986 {
 987         struct ib_qp_attr qp_attr;
 988         int attr_mask;
 989         int ret;
 990
 991         qp_attr.qp_state = IB_QPS_RTR;
 992         ret = ib_cm_init_qp_attr(ch->cm_id, &qp_attr, &attr_mask);
 993         if (ret)
 994                 goto out;
 995
 996         qp_attr.max_dest_rd_atomic = 4;
 997
 998         ret = ib_modify_qp(qp, &qp_attr, attr_mask);
 999
1000 out:
1001         return ret;
1002 }
1003
1004 /**
1005  * srpt_ch_qp_rts() - Change the state of a channel to 'ready to send' (RTS).
1006  * @ch: channel of the queue pair.
1007  * @qp: queue pair to change the state of.
1008  *
1009  * Returns zero upon success and a negative value upon failure.
1010  *
1011  * Note: currently a struct ib_qp_attr takes 136 bytes on a 64-bit system.
1012  * If this structure ever becomes larger, it might be necessary to allocate
1013  * it dynamically instead of on the stack.
1014  */
1015 static int srpt_ch_qp_rts(struct srpt_rdma_ch *ch, struct ib_qp *qp)
1016 {
1017         struct ib_qp_attr qp_attr;
1018         int attr_mask;
1019         int ret;
1020
1021         qp_attr.qp_state = IB_QPS_RTS;
1022         ret = ib_cm_init_qp_attr(ch->cm_id, &qp_attr, &attr_mask);
1023         if (ret)
1024                 goto out;
1025
1026         qp_attr.max_rd_atomic = 4;
1027
1028         ret = ib_modify_qp(qp, &qp_attr, attr_mask);
1029
1030 out:
1031         return ret;
1032 }
1033
1034 /**
1035  * srpt_ch_qp_err() - Set the channel queue pair state to 'error'.
1036  */
1037 static int srpt_ch_qp_err(struct srpt_rdma_ch *ch)
1038 {
1039         struct ib_qp_attr qp_attr;
1040
1041         qp_attr.qp_state = IB_QPS_ERR;
1042         return ib_modify_qp(ch->qp, &qp_attr, IB_QP_STATE);
1043 }
1044
1045 /**
1046  * srpt_unmap_sg_to_ib_sge() - Unmap an IB SGE list.
1047  */
1048 static void srpt_unmap_sg_to_ib_sge(struct srpt_rdma_ch *ch,
1049                                     struct srpt_send_ioctx *ioctx)
1050 {
1051         struct scatterlist *sg;
1052         enum dma_data_direction dir;
1053
1054         BUG_ON(!ch);
1055         BUG_ON(!ioctx);
1056         BUG_ON(ioctx->n_rdma && !ioctx->rdma_ius);
1057
1058         while (ioctx->n_rdma)
1059                 kfree(ioctx->rdma_ius[--ioctx->n_rdma].sge);
1060
1061         kfree(ioctx->rdma_ius);
1062         ioctx->rdma_ius = NULL;
1063
1064         if (ioctx->mapped_sg_count) {
1065                 sg = ioctx->sg;
1066                 WARN_ON(!sg);
1067                 dir = ioctx->cmd.data_direction;
1068                 BUG_ON(dir == DMA_NONE);
1069                 ib_dma_unmap_sg(ch->sport->sdev->device, sg, ioctx->sg_cnt,
1070                                 opposite_dma_dir(dir));
1071                 ioctx->mapped_sg_count = 0;
1072         }
1073 }
1074
1075 /**
1076  * srpt_map_sg_to_ib_sge() - Map an SG list to an IB SGE list.
1077  */
1078 static int srpt_map_sg_to_ib_sge(struct srpt_rdma_ch *ch,
1079                                  struct srpt_send_ioctx *ioctx)
1080 {
1081         struct se_cmd *cmd;
1082         struct scatterlist *sg, *sg_orig;
1083         int sg_cnt;
1084         enum dma_data_direction dir;
1085         struct rdma_iu *riu;
1086         struct srp_direct_buf *db;
1087         dma_addr_t dma_addr;
1088         struct ib_sge *sge;
1089         u64 raddr;
1090         u32 rsize;
1091         u32 tsize;
1092         u32 dma_len;
1093         int count, nrdma;
1094         int i, j, k;
1095
1096         BUG_ON(!ch);
1097         BUG_ON(!ioctx);
1098         cmd = &ioctx->cmd;
1099         dir = cmd->data_direction;
1100         BUG_ON(dir == DMA_NONE);
1101
1102         transport_do_task_sg_chain(cmd);
1103         ioctx->sg = sg = sg_orig = cmd->t_tasks_sg_chained;
1104         ioctx->sg_cnt = sg_cnt = cmd->t_tasks_sg_chained_no;
1105
1106         count = ib_dma_map_sg(ch->sport->sdev->device, sg, sg_cnt,
1107                               opposite_dma_dir(dir));
1108         if (unlikely(!count))
1109                 return -EAGAIN;
1110
1111         ioctx->mapped_sg_count = count;
1112
1113         if (ioctx->rdma_ius && ioctx->n_rdma_ius)
1114                 nrdma = ioctx->n_rdma_ius;
1115         else {
1116                 nrdma = (count + SRPT_DEF_SG_PER_WQE - 1) / SRPT_DEF_SG_PER_WQE
1117                         + ioctx->n_rbuf;
1118
1119                 ioctx->rdma_ius = kzalloc(nrdma * sizeof *riu, GFP_KERNEL);
1120                 if (!ioctx->rdma_ius)
1121                         goto free_mem;
1122
1123                 ioctx->n_rdma_ius = nrdma;
1124         }
1125
1126         db = ioctx->rbufs;
1127         tsize = cmd->data_length;
1128         dma_len = sg_dma_len(&sg[0]);
1129         riu = ioctx->rdma_ius;
1130
1131         /*
1132          * For each remote desc - calculate the #ib_sge.
1133          * If #ib_sge < SRPT_DEF_SG_PER_WQE per rdma operation then
1134          *      each remote desc rdma_iu is required a rdma wr;
1135          * else
1136          *      we need to allocate extra rdma_iu to carry extra #ib_sge in
1137          *      another rdma wr
1138          */
1139         for (i = 0, j = 0;
1140              j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) {
1141                 rsize = be32_to_cpu(db->len);
1142                 raddr = be64_to_cpu(db->va);
1143                 riu->raddr = raddr;
1144                 riu->rkey = be32_to_cpu(db->key);
1145                 riu->sge_cnt = 0;
1146
1147                 /* calculate how many sge required for this remote_buf */
1148                 while (rsize > 0 && tsize > 0) {
1149
1150                         if (rsize >= dma_len) {
1151                                 tsize -= dma_len;
1152                                 rsize -= dma_len;
1153                                 raddr += dma_len;
1154
1155                                 if (tsize > 0) {
1156                                         ++j;
1157                                         if (j < count) {
1158                                                 sg = sg_next(sg);
1159                                                 dma_len = sg_dma_len(sg);
1160                                         }
1161                                 }
1162                         } else {
1163                                 tsize -= rsize;
1164                                 dma_len -= rsize;
1165                                 rsize = 0;
1166                         }
1167
1168                         ++riu->sge_cnt;
1169
1170                         if (rsize > 0 && riu->sge_cnt == SRPT_DEF_SG_PER_WQE) {
1171                                 ++ioctx->n_rdma;
1172                                 riu->sge =
1173                                     kmalloc(riu->sge_cnt * sizeof *riu->sge,
1174                                             GFP_KERNEL);
1175                                 if (!riu->sge)
1176                                         goto free_mem;
1177
1178                                 ++riu;
1179                                 riu->sge_cnt = 0;
1180                                 riu->raddr = raddr;
1181                                 riu->rkey = be32_to_cpu(db->key);
1182                         }
1183                 }
1184
1185                 ++ioctx->n_rdma;
1186                 riu->sge = kmalloc(riu->sge_cnt * sizeof *riu->sge,
1187                                    GFP_KERNEL);
1188                 if (!riu->sge)
1189                         goto free_mem;
1190         }
1191
1192         db = ioctx->rbufs;
1193         tsize = cmd->data_length;
1194         riu = ioctx->rdma_ius;
1195         sg = sg_orig;
1196         dma_len = sg_dma_len(&sg[0]);
1197         dma_addr = sg_dma_address(&sg[0]);
1198
1199         /* this second loop is really mapped sg_addres to rdma_iu->ib_sge */
1200         for (i = 0, j = 0;
1201              j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) {
1202                 rsize = be32_to_cpu(db->len);
1203                 sge = riu->sge;
1204                 k = 0;
1205
1206                 while (rsize > 0 && tsize > 0) {
1207                         sge->addr = dma_addr;
1208                         sge->lkey = ch->sport->sdev->mr->lkey;
1209
1210                         if (rsize >= dma_len) {
1211                                 sge->length =
1212                                         (tsize < dma_len) ? tsize : dma_len;
1213                                 tsize -= dma_len;
1214                                 rsize -= dma_len;
1215
1216                                 if (tsize > 0) {
1217                                         ++j;
1218                                         if (j < count) {
1219                                                 sg = sg_next(sg);
1220                                                 dma_len = sg_dma_len(sg);
1221                                                 dma_addr = sg_dma_address(sg);
1222                                         }
1223                                 }
1224                         } else {
1225                                 sge->length = (tsize < rsize) ? tsize : rsize;
1226                                 tsize -= rsize;
1227                                 dma_len -= rsize;
1228                                 dma_addr += rsize;
1229                                 rsize = 0;
1230                         }
1231
1232                         ++k;
1233                         if (k == riu->sge_cnt && rsize > 0 && tsize > 0) {
1234                                 ++riu;
1235                                 sge = riu->sge;
1236                                 k = 0;
1237                         } else if (rsize > 0 && tsize > 0)
1238                                 ++sge;
1239                 }
1240         }
1241
1242         return 0;
1243
1244 free_mem:
1245         srpt_unmap_sg_to_ib_sge(ch, ioctx);
1246
1247         return -ENOMEM;
1248 }
1249
1250 /**
1251  * srpt_get_send_ioctx() - Obtain an I/O context for sending to the initiator.
1252  */
1253 static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)
1254 {
1255         struct srpt_send_ioctx *ioctx;
1256         unsigned long flags;
1257
1258         BUG_ON(!ch);
1259
1260         ioctx = NULL;
1261         spin_lock_irqsave(&ch->spinlock, flags);
1262         if (!list_empty(&ch->free_list)) {
1263                 ioctx = list_first_entry(&ch->free_list,
1264                                          struct srpt_send_ioctx, free_list);
1265                 list_del(&ioctx->free_list);
1266         }
1267         spin_unlock_irqrestore(&ch->spinlock, flags);
1268
1269         if (!ioctx)
1270                 return ioctx;
1271
1272         BUG_ON(ioctx->ch != ch);
1273         kref_init(&ioctx->kref);
1274         spin_lock_init(&ioctx->spinlock);
1275         ioctx->state = SRPT_STATE_NEW;
1276         ioctx->n_rbuf = 0;
1277         ioctx->rbufs = NULL;
1278         ioctx->n_rdma = 0;
1279         ioctx->n_rdma_ius = 0;
1280         ioctx->rdma_ius = NULL;
1281         ioctx->mapped_sg_count = 0;
1282         init_completion(&ioctx->tx_done);
1283         ioctx->queue_status_only = false;
1284         /*
1285          * transport_init_se_cmd() does not initialize all fields, so do it
1286          * here.
1287          */
1288         memset(&ioctx->cmd, 0, sizeof(ioctx->cmd));
1289         memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data));
1290
1291         return ioctx;
1292 }
1293
1294 /**
1295  * srpt_put_send_ioctx() - Free up resources.
1296  */
1297 static void srpt_put_send_ioctx(struct srpt_send_ioctx *ioctx)
1298 {
1299         struct srpt_rdma_ch *ch;
1300         unsigned long flags;
1301
1302         BUG_ON(!ioctx);
1303         ch = ioctx->ch;
1304         BUG_ON(!ch);
1305
1306         WARN_ON(srpt_get_cmd_state(ioctx) != SRPT_STATE_DONE);
1307
1308         srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx);
1309         transport_generic_free_cmd(&ioctx->cmd, 0);
1310
1311         if (ioctx->n_rbuf > 1) {
1312                 kfree(ioctx->rbufs);
1313                 ioctx->rbufs = NULL;
1314                 ioctx->n_rbuf = 0;
1315         }
1316
1317         spin_lock_irqsave(&ch->spinlock, flags);
1318         list_add(&ioctx->free_list, &ch->free_list);
1319         spin_unlock_irqrestore(&ch->spinlock, flags);
1320 }
1321
1322 static void srpt_put_send_ioctx_kref(struct kref *kref)
1323 {
1324         srpt_put_send_ioctx(container_of(kref, struct srpt_send_ioctx, kref));
1325 }
1326
1327 /**
1328  * srpt_abort_cmd() - Abort a SCSI command.
1329  * @ioctx:   I/O context associated with the SCSI command.
1330  * @context: Preferred execution context.
1331  */
1332 static int srpt_abort_cmd(struct srpt_send_ioctx *ioctx)
1333 {
1334         enum srpt_command_state state;
1335         unsigned long flags;
1336
1337         BUG_ON(!ioctx);
1338
1339         /*
1340          * If the command is in a state where the target core is waiting for
1341          * the ib_srpt driver, change the state to the next state. Changing
1342          * the state of the command from SRPT_STATE_NEED_DATA to
1343          * SRPT_STATE_DATA_IN ensures that srpt_xmit_response() will call this
1344          * function a second time.
1345          */
1346
1347         spin_lock_irqsave(&ioctx->spinlock, flags);
1348         state = ioctx->state;
1349         switch (state) {
1350         case SRPT_STATE_NEED_DATA:
1351                 ioctx->state = SRPT_STATE_DATA_IN;
1352                 break;
1353         case SRPT_STATE_DATA_IN:
1354         case SRPT_STATE_CMD_RSP_SENT:
1355         case SRPT_STATE_MGMT_RSP_SENT:
1356                 ioctx->state = SRPT_STATE_DONE;
1357                 break;
1358         default:
1359                 break;
1360         }
1361         spin_unlock_irqrestore(&ioctx->spinlock, flags);
1362
1363         if (state == SRPT_STATE_DONE)
1364                 goto out;
1365
1366         pr_debug("Aborting cmd with state %d and tag %lld\n", state,
1367                  ioctx->tag);
1368
1369         switch (state) {
1370         case SRPT_STATE_NEW:
1371         case SRPT_STATE_DATA_IN:
1372         case SRPT_STATE_MGMT:
1373                 /*
1374                  * Do nothing - defer abort processing until
1375                  * srpt_queue_response() is invoked.
1376                  */
1377                 WARN_ON(!transport_check_aborted_status(&ioctx->cmd, false));
1378                 break;
1379         case SRPT_STATE_NEED_DATA:
1380                 /* DMA_TO_DEVICE (write) - RDMA read error. */
1381                 atomic_set(&ioctx->cmd.transport_lun_stop, 1);
1382                 transport_generic_handle_data(&ioctx->cmd);
1383                 break;
1384         case SRPT_STATE_CMD_RSP_SENT:
1385                 /*
1386                  * SRP_RSP sending failed or the SRP_RSP send completion has
1387                  * not been received in time.
1388                  */
1389                 srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx);
1390                 atomic_set(&ioctx->cmd.transport_lun_stop, 1);
1391                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1392                 break;
1393         case SRPT_STATE_MGMT_RSP_SENT:
1394                 srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
1395                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1396                 break;
1397         default:
1398                 WARN_ON("ERROR: unexpected command state");
1399                 break;
1400         }
1401
1402 out:
1403         return state;
1404 }
1405
1406 /**
1407  * srpt_handle_send_err_comp() - Process an IB_WC_SEND error completion.
1408  */
1409 static void srpt_handle_send_err_comp(struct srpt_rdma_ch *ch, u64 wr_id)
1410 {
1411         struct srpt_send_ioctx *ioctx;
1412         enum srpt_command_state state;
1413         struct se_cmd *cmd;
1414         u32 index;
1415
1416         atomic_inc(&ch->sq_wr_avail);
1417
1418         index = idx_from_wr_id(wr_id);
1419         ioctx = ch->ioctx_ring[index];
1420         state = srpt_get_cmd_state(ioctx);
1421         cmd = &ioctx->cmd;
1422
1423         WARN_ON(state != SRPT_STATE_CMD_RSP_SENT
1424                 && state != SRPT_STATE_MGMT_RSP_SENT
1425                 && state != SRPT_STATE_NEED_DATA
1426                 && state != SRPT_STATE_DONE);
1427
1428         /* If SRP_RSP sending failed, undo the ch->req_lim change. */
1429         if (state == SRPT_STATE_CMD_RSP_SENT
1430             || state == SRPT_STATE_MGMT_RSP_SENT)
1431                 atomic_dec(&ch->req_lim);
1432
1433         srpt_abort_cmd(ioctx);
1434 }
1435
1436 /**
1437  * srpt_handle_send_comp() - Process an IB send completion notification.
1438  */
1439 static void srpt_handle_send_comp(struct srpt_rdma_ch *ch,
1440                                   struct srpt_send_ioctx *ioctx)
1441 {
1442         enum srpt_command_state state;
1443
1444         atomic_inc(&ch->sq_wr_avail);
1445
1446         state = srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
1447
1448         if (WARN_ON(state != SRPT_STATE_CMD_RSP_SENT
1449                     && state != SRPT_STATE_MGMT_RSP_SENT
1450                     && state != SRPT_STATE_DONE))
1451                 pr_debug("state = %d\n", state);
1452
1453         if (state != SRPT_STATE_DONE)
1454                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1455         else
1456                 printk(KERN_ERR "IB completion has been received too late for"
1457                        " wr_id = %u.\n", ioctx->ioctx.index);
1458 }
1459
1460 /**
1461  * srpt_handle_rdma_comp() - Process an IB RDMA completion notification.
1462  *
1463  * Note: transport_generic_handle_data() is asynchronous so unmapping the
1464  * data that has been transferred via IB RDMA must be postponed until the
1465  * check_stop_free() callback.
1466  */
1467 static void srpt_handle_rdma_comp(struct srpt_rdma_ch *ch,
1468                                   struct srpt_send_ioctx *ioctx,
1469                                   enum srpt_opcode opcode)
1470 {
1471         WARN_ON(ioctx->n_rdma <= 0);
1472         atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);
1473
1474         if (opcode == SRPT_RDMA_READ_LAST) {
1475                 if (srpt_test_and_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA,
1476                                                 SRPT_STATE_DATA_IN))
1477                         transport_generic_handle_data(&ioctx->cmd);
1478                 else
1479                         printk(KERN_ERR "%s[%d]: wrong state = %d\n", __func__,
1480                                __LINE__, srpt_get_cmd_state(ioctx));
1481         } else if (opcode == SRPT_RDMA_ABORT) {
1482                 ioctx->rdma_aborted = true;
1483         } else {
1484                 WARN(true, "unexpected opcode %d\n", opcode);
1485         }
1486 }
1487
1488 /**
1489  * srpt_handle_rdma_err_comp() - Process an IB RDMA error completion.
1490  */
1491 static void srpt_handle_rdma_err_comp(struct srpt_rdma_ch *ch,
1492                                       struct srpt_send_ioctx *ioctx,
1493                                       enum srpt_opcode opcode)
1494 {
1495         struct se_cmd *cmd;
1496         enum srpt_command_state state;
1497
1498         cmd = &ioctx->cmd;
1499         state = srpt_get_cmd_state(ioctx);
1500         switch (opcode) {
1501         case SRPT_RDMA_READ_LAST:
1502                 if (ioctx->n_rdma <= 0) {
1503                         printk(KERN_ERR "Received invalid RDMA read"
1504                                " error completion with idx %d\n",
1505                                ioctx->ioctx.index);
1506                         break;
1507                 }
1508                 atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);
1509                 if (state == SRPT_STATE_NEED_DATA)
1510                         srpt_abort_cmd(ioctx);
1511                 else
1512                         printk(KERN_ERR "%s[%d]: wrong state = %d\n",
1513                                __func__, __LINE__, state);
1514                 break;
1515         case SRPT_RDMA_WRITE_LAST:
1516                 atomic_set(&ioctx->cmd.transport_lun_stop, 1);
1517                 break;
1518         default:
1519                 printk(KERN_ERR "%s[%d]: opcode = %u\n", __func__,
1520                        __LINE__, opcode);
1521                 break;
1522         }
1523 }
1524
1525 /**
1526  * srpt_build_cmd_rsp() - Build an SRP_RSP response.
1527  * @ch: RDMA channel through which the request has been received.
1528  * @ioctx: I/O context associated with the SRP_CMD request. The response will
1529  *   be built in the buffer ioctx->buf points at and hence this function will
1530  *   overwrite the request data.
1531  * @tag: tag of the request for which this response is being generated.
1532  * @status: value for the STATUS field of the SRP_RSP information unit.
1533  *
1534  * Returns the size in bytes of the SRP_RSP response.
1535  *
1536  * An SRP_RSP response contains a SCSI status or service response. See also
1537  * section 6.9 in the SRP r16a document for the format of an SRP_RSP
1538  * response. See also SPC-2 for more information about sense data.
1539  */
1540 static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,
1541                               struct srpt_send_ioctx *ioctx, u64 tag,
1542                               int status)
1543 {
1544         struct srp_rsp *srp_rsp;
1545         const u8 *sense_data;
1546         int sense_data_len, max_sense_len;
1547
1548         /*
1549          * The lowest bit of all SAM-3 status codes is zero (see also
1550          * paragraph 5.3 in SAM-3).
1551          */
1552         WARN_ON(status & 1);
1553
1554         srp_rsp = ioctx->ioctx.buf;
1555         BUG_ON(!srp_rsp);
1556
1557         sense_data = ioctx->sense_data;
1558         sense_data_len = ioctx->cmd.scsi_sense_length;
1559         WARN_ON(sense_data_len > sizeof(ioctx->sense_data));
1560
1561         memset(srp_rsp, 0, sizeof *srp_rsp);
1562         srp_rsp->opcode = SRP_RSP;
1563         srp_rsp->req_lim_delta =
1564                 __constant_cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0));
1565         srp_rsp->tag = tag;
1566         srp_rsp->status = status;
1567
1568         if (sense_data_len) {
1569                 BUILD_BUG_ON(MIN_MAX_RSP_SIZE <= sizeof(*srp_rsp));
1570                 max_sense_len = ch->max_ti_iu_len - sizeof(*srp_rsp);
1571                 if (sense_data_len > max_sense_len) {
1572                         printk(KERN_WARNING "truncated sense data from %d to %d"
1573                                " bytes\n", sense_data_len, max_sense_len);
1574                         sense_data_len = max_sense_len;
1575                 }
1576
1577                 srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;
1578                 srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);
1579                 memcpy(srp_rsp + 1, sense_data, sense_data_len);
1580         }
1581
1582         return sizeof(*srp_rsp) + sense_data_len;
1583 }
1584
1585 /**
1586  * srpt_build_tskmgmt_rsp() - Build a task management response.
1587  * @ch:       RDMA channel through which the request has been received.
1588  * @ioctx:    I/O context in which the SRP_RSP response will be built.
1589  * @rsp_code: RSP_CODE that will be stored in the response.
1590  * @tag:      Tag of the request for which this response is being generated.
1591  *
1592  * Returns the size in bytes of the SRP_RSP response.
1593  *
1594  * An SRP_RSP response contains a SCSI status or service response. See also
1595  * section 6.9 in the SRP r16a document for the format of an SRP_RSP
1596  * response.
1597  */
1598 static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,
1599                                   struct srpt_send_ioctx *ioctx,
1600                                   u8 rsp_code, u64 tag)
1601 {
1602         struct srp_rsp *srp_rsp;
1603         int resp_data_len;
1604         int resp_len;
1605
1606         resp_data_len = (rsp_code == SRP_TSK_MGMT_SUCCESS) ? 0 : 4;
1607         resp_len = sizeof(*srp_rsp) + resp_data_len;
1608
1609         srp_rsp = ioctx->ioctx.buf;
1610         BUG_ON(!srp_rsp);
1611         memset(srp_rsp, 0, sizeof *srp_rsp);
1612
1613         srp_rsp->opcode = SRP_RSP;
1614         srp_rsp->req_lim_delta = __constant_cpu_to_be32(1
1615                                     + atomic_xchg(&ch->req_lim_delta, 0));
1616         srp_rsp->tag = tag;
1617
1618         if (rsp_code != SRP_TSK_MGMT_SUCCESS) {
1619                 srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID;
1620                 srp_rsp->resp_data_len = cpu_to_be32(resp_data_len);
1621                 srp_rsp->data[3] = rsp_code;
1622         }
1623
1624         return resp_len;
1625 }
1626
1627 #define NO_SUCH_LUN ((uint64_t)-1LL)
1628
1629 /*
1630  * SCSI LUN addressing method. See also SAM-2 and the section about
1631  * eight byte LUNs.
1632  */
1633 enum scsi_lun_addr_method {
1634         SCSI_LUN_ADDR_METHOD_PERIPHERAL   = 0,
1635         SCSI_LUN_ADDR_METHOD_FLAT         = 1,
1636         SCSI_LUN_ADDR_METHOD_LUN          = 2,
1637         SCSI_LUN_ADDR_METHOD_EXTENDED_LUN = 3,
1638 };
1639
1640 /*
1641  * srpt_unpack_lun() - Convert from network LUN to linear LUN.
1642  *
1643  * Convert an 2-byte, 4-byte, 6-byte or 8-byte LUN structure in network byte
1644  * order (big endian) to a linear LUN. Supports three LUN addressing methods:
1645  * peripheral, flat and logical unit. See also SAM-2, section 4.9.4 (page 40).
1646  */
1647 static uint64_t srpt_unpack_lun(const uint8_t *lun, int len)
1648 {
1649         uint64_t res = NO_SUCH_LUN;
1650         int addressing_method;
1651
1652         if (unlikely(len < 2)) {
1653                 printk(KERN_ERR "Illegal LUN length %d, expected 2 bytes or "
1654                        "more", len);
1655                 goto out;
1656         }
1657
1658         switch (len) {
1659         case 8:
1660                 if ((*((__be64 *)lun) &
1661                      __constant_cpu_to_be64(0x0000FFFFFFFFFFFFLL)) != 0)
1662                         goto out_err;
1663                 break;
1664         case 4:
1665                 if (*((__be16 *)&lun[2]) != 0)
1666                         goto out_err;
1667                 break;
1668         case 6:
1669                 if (*((__be32 *)&lun[2]) != 0)
1670                         goto out_err;
1671                 break;
1672         case 2:
1673                 break;
1674         default:
1675                 goto out_err;
1676         }
1677
1678         addressing_method = (*lun) >> 6; /* highest two bits of byte 0 */
1679         switch (addressing_method) {
1680         case SCSI_LUN_ADDR_METHOD_PERIPHERAL:
1681         case SCSI_LUN_ADDR_METHOD_FLAT:
1682         case SCSI_LUN_ADDR_METHOD_LUN:
1683                 res = *(lun + 1) | (((*lun) & 0x3f) << 8);
1684                 break;
1685
1686         case SCSI_LUN_ADDR_METHOD_EXTENDED_LUN:
1687         default:
1688                 printk(KERN_ERR "Unimplemented LUN addressing method %u",
1689                        addressing_method);
1690                 break;
1691         }
1692
1693 out:
1694         return res;
1695
1696 out_err:
1697         printk(KERN_ERR "Support for multi-level LUNs has not yet been"
1698                " implemented");
1699         goto out;
1700 }
1701
1702 static int srpt_check_stop_free(struct se_cmd *cmd)
1703 {
1704         struct srpt_send_ioctx *ioctx;
1705
1706         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
1707         return kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1708 }
1709
1710 /**
1711  * srpt_handle_cmd() - Process SRP_CMD.
1712  */
1713 static int srpt_handle_cmd(struct srpt_rdma_ch *ch,
1714                            struct srpt_recv_ioctx *recv_ioctx,
1715                            struct srpt_send_ioctx *send_ioctx)
1716 {
1717         struct se_cmd *cmd;
1718         struct srp_cmd *srp_cmd;
1719         uint64_t unpacked_lun;
1720         u64 data_len;
1721         enum dma_data_direction dir;
1722         int ret;
1723
1724         BUG_ON(!send_ioctx);
1725
1726         srp_cmd = recv_ioctx->ioctx.buf;
1727         kref_get(&send_ioctx->kref);
1728         cmd = &send_ioctx->cmd;
1729         send_ioctx->tag = srp_cmd->tag;
1730
1731         switch (srp_cmd->task_attr) {
1732         case SRP_CMD_SIMPLE_Q:
1733                 cmd->sam_task_attr = MSG_SIMPLE_TAG;
1734                 break;
1735         case SRP_CMD_ORDERED_Q:
1736         default:
1737                 cmd->sam_task_attr = MSG_ORDERED_TAG;
1738                 break;
1739         case SRP_CMD_HEAD_OF_Q:
1740                 cmd->sam_task_attr = MSG_HEAD_TAG;
1741                 break;
1742         case SRP_CMD_ACA:
1743                 cmd->sam_task_attr = MSG_ACA_TAG;
1744                 break;
1745         }
1746
1747         ret = srpt_get_desc_tbl(send_ioctx, srp_cmd, &dir, &data_len);
1748         if (ret) {
1749                 printk(KERN_ERR "0x%llx: parsing SRP descriptor table failed.\n",
1750                        srp_cmd->tag);
1751                 cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1752                 cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1753                 goto send_sense;
1754         }
1755
1756         cmd->data_length = data_len;
1757         cmd->data_direction = dir;
1758         unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_cmd->lun,
1759                                        sizeof(srp_cmd->lun));
1760         if (transport_lookup_cmd_lun(cmd, unpacked_lun) < 0)
1761                 goto send_sense;
1762         ret = transport_generic_allocate_tasks(cmd, srp_cmd->cdb);
1763         if (cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
1764                 srpt_queue_status(cmd);
1765         else if (cmd->se_cmd_flags & SCF_SCSI_CDB_EXCEPTION)
1766                 goto send_sense;
1767         else
1768                 WARN_ON_ONCE(ret);
1769
1770         transport_handle_cdb_direct(cmd);
1771         return 0;
1772
1773 send_sense:
1774         transport_send_check_condition_and_sense(cmd, cmd->scsi_sense_reason,
1775                                                  0);
1776         return -1;
1777 }
1778
1779 /**
1780  * srpt_rx_mgmt_fn_tag() - Process a task management function by tag.
1781  * @ch: RDMA channel of the task management request.
1782  * @fn: Task management function to perform.
1783  * @req_tag: Tag of the SRP task management request.
1784  * @mgmt_ioctx: I/O context of the task management request.
1785  *
1786  * Returns zero if the target core will process the task management
1787  * request asynchronously.
1788  *
1789  * Note: It is assumed that the initiator serializes tag-based task management
1790  * requests.
1791  */
1792 static int srpt_rx_mgmt_fn_tag(struct srpt_send_ioctx *ioctx, u64 tag)
1793 {
1794         struct srpt_device *sdev;
1795         struct srpt_rdma_ch *ch;
1796         struct srpt_send_ioctx *target;
1797         int ret, i;
1798
1799         ret = -EINVAL;
1800         ch = ioctx->ch;
1801         BUG_ON(!ch);
1802         BUG_ON(!ch->sport);
1803         sdev = ch->sport->sdev;
1804         BUG_ON(!sdev);
1805         spin_lock_irq(&sdev->spinlock);
1806         for (i = 0; i < ch->rq_size; ++i) {
1807                 target = ch->ioctx_ring[i];
1808                 if (target->cmd.se_lun == ioctx->cmd.se_lun &&
1809                     target->tag == tag &&
1810                     srpt_get_cmd_state(target) != SRPT_STATE_DONE) {
1811                         ret = 0;
1812                         /* now let the target core abort &target->cmd; */
1813                         break;
1814                 }
1815         }
1816         spin_unlock_irq(&sdev->spinlock);
1817         return ret;
1818 }
1819
1820 static int srp_tmr_to_tcm(int fn)
1821 {
1822         switch (fn) {
1823         case SRP_TSK_ABORT_TASK:
1824                 return TMR_ABORT_TASK;
1825         case SRP_TSK_ABORT_TASK_SET:
1826                 return TMR_ABORT_TASK_SET;
1827         case SRP_TSK_CLEAR_TASK_SET:
1828                 return TMR_CLEAR_TASK_SET;
1829         case SRP_TSK_LUN_RESET:
1830                 return TMR_LUN_RESET;
1831         case SRP_TSK_CLEAR_ACA:
1832                 return TMR_CLEAR_ACA;
1833         default:
1834                 return -1;
1835         }
1836 }
1837
1838 /**
1839  * srpt_handle_tsk_mgmt() - Process an SRP_TSK_MGMT information unit.
1840  *
1841  * Returns 0 if and only if the request will be processed by the target core.
1842  *
1843  * For more information about SRP_TSK_MGMT information units, see also section
1844  * 6.7 in the SRP r16a document.
1845  */
1846 static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,
1847                                  struct srpt_recv_ioctx *recv_ioctx,
1848                                  struct srpt_send_ioctx *send_ioctx)
1849 {
1850         struct srp_tsk_mgmt *srp_tsk;
1851         struct se_cmd *cmd;
1852         uint64_t unpacked_lun;
1853         int tcm_tmr;
1854         int res;
1855
1856         BUG_ON(!send_ioctx);
1857
1858         srp_tsk = recv_ioctx->ioctx.buf;
1859         cmd = &send_ioctx->cmd;
1860
1861         pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld"
1862                  " cm_id %p sess %p\n", srp_tsk->tsk_mgmt_func,
1863                  srp_tsk->task_tag, srp_tsk->tag, ch->cm_id, ch->sess);
1864
1865         srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT);
1866         send_ioctx->tag = srp_tsk->tag;
1867         tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func);
1868         if (tcm_tmr < 0) {
1869                 send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1870                 send_ioctx->cmd.se_tmr_req->response =
1871                         TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
1872                 goto process_tmr;
1873         }
1874         cmd->se_tmr_req = core_tmr_alloc_req(cmd, NULL, tcm_tmr, GFP_KERNEL);
1875         if (!cmd->se_tmr_req) {
1876                 send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1877                 send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED;
1878                 goto process_tmr;
1879         }
1880
1881         unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_tsk->lun,
1882                                        sizeof(srp_tsk->lun));
1883         res = transport_lookup_tmr_lun(&send_ioctx->cmd, unpacked_lun);
1884         if (res) {
1885                 pr_debug("rejecting TMR for LUN %lld\n", unpacked_lun);
1886                 send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1887                 send_ioctx->cmd.se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1888                 goto process_tmr;
1889         }
1890
1891         if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK)
1892                 srpt_rx_mgmt_fn_tag(send_ioctx, srp_tsk->task_tag);
1893
1894 process_tmr:
1895         kref_get(&send_ioctx->kref);
1896         if (!(send_ioctx->cmd.se_cmd_flags & SCF_SCSI_CDB_EXCEPTION))
1897                 transport_generic_handle_tmr(&send_ioctx->cmd);
1898         else
1899                 transport_send_check_condition_and_sense(cmd,
1900                                                 cmd->scsi_sense_reason, 0);
1901
1902 }
1903
1904 /**
1905  * srpt_handle_new_iu() - Process a newly received information unit.
1906  * @ch:    RDMA channel through which the information unit has been received.
1907  * @ioctx: SRPT I/O context associated with the information unit.
1908  */
1909 static void srpt_handle_new_iu(struct srpt_rdma_ch *ch,
1910                                struct srpt_recv_ioctx *recv_ioctx,
1911                                struct srpt_send_ioctx *send_ioctx)
1912 {
1913         struct srp_cmd *srp_cmd;
1914         enum rdma_ch_state ch_state;
1915
1916         BUG_ON(!ch);
1917         BUG_ON(!recv_ioctx);
1918
1919         ib_dma_sync_single_for_cpu(ch->sport->sdev->device,
1920                                    recv_ioctx->ioctx.dma, srp_max_req_size,
1921                                    DMA_FROM_DEVICE);
1922
1923         ch_state = srpt_get_ch_state(ch);
1924         if (unlikely(ch_state == CH_CONNECTING)) {
1925                 list_add_tail(&recv_ioctx->wait_list, &ch->cmd_wait_list);
1926                 goto out;
1927         }
1928
1929         if (unlikely(ch_state != CH_LIVE))
1930                 goto out;
1931
1932         srp_cmd = recv_ioctx->ioctx.buf;
1933         if (srp_cmd->opcode == SRP_CMD || srp_cmd->opcode == SRP_TSK_MGMT) {
1934                 if (!send_ioctx)
1935                         send_ioctx = srpt_get_send_ioctx(ch);
1936                 if (unlikely(!send_ioctx)) {
1937                         list_add_tail(&recv_ioctx->wait_list,
1938                                       &ch->cmd_wait_list);
1939                         goto out;
1940                 }
1941         }
1942
1943         transport_init_se_cmd(&send_ioctx->cmd, &srpt_target->tf_ops, ch->sess,
1944                               0, DMA_NONE, MSG_SIMPLE_TAG,
1945                               send_ioctx->sense_data);
1946
1947         switch (srp_cmd->opcode) {
1948         case SRP_CMD:
1949                 srpt_handle_cmd(ch, recv_ioctx, send_ioctx);
1950                 break;
1951         case SRP_TSK_MGMT:
1952                 srpt_handle_tsk_mgmt(ch, recv_ioctx, send_ioctx);
1953                 break;
1954         case SRP_I_LOGOUT:
1955                 printk(KERN_ERR "Not yet implemented: SRP_I_LOGOUT\n");
1956                 break;
1957         case SRP_CRED_RSP:
1958                 pr_debug("received SRP_CRED_RSP\n");
1959                 break;
1960         case SRP_AER_RSP:
1961                 pr_debug("received SRP_AER_RSP\n");
1962                 break;
1963         case SRP_RSP:
1964                 printk(KERN_ERR "Received SRP_RSP\n");
1965                 break;
1966         default:
1967                 printk(KERN_ERR "received IU with unknown opcode 0x%x\n",
1968                        srp_cmd->opcode);
1969                 break;
1970         }
1971
1972         srpt_post_recv(ch->sport->sdev, recv_ioctx);
1973 out:
1974         return;
1975 }
1976
1977 static void srpt_process_rcv_completion(struct ib_cq *cq,
1978                                         struct srpt_rdma_ch *ch,
1979                                         struct ib_wc *wc)
1980 {
1981         struct srpt_device *sdev = ch->sport->sdev;
1982         struct srpt_recv_ioctx *ioctx;
1983         u32 index;
1984
1985         index = idx_from_wr_id(wc->wr_id);
1986         if (wc->status == IB_WC_SUCCESS) {
1987                 int req_lim;
1988
1989                 req_lim = atomic_dec_return(&ch->req_lim);
1990                 if (unlikely(req_lim < 0))
1991                         printk(KERN_ERR "req_lim = %d < 0\n", req_lim);
1992                 ioctx = sdev->ioctx_ring[index];
1993                 srpt_handle_new_iu(ch, ioctx, NULL);
1994         } else {
1995                 printk(KERN_INFO "receiving failed for idx %u with status %d\n",
1996                        index, wc->status);
1997         }
1998 }
1999
2000 /**
2001  * srpt_process_send_completion() - Process an IB send completion.
2002  *
2003  * Note: Although this has not yet been observed during tests, at least in
2004  * theory it is possible that the srpt_get_send_ioctx() call invoked by
2005  * srpt_handle_new_iu() fails. This is possible because the req_lim_delta
2006  * value in each response is set to one, and it is possible that this response
2007  * makes the initiator send a new request before the send completion for that
2008  * response has been processed. This could e.g. happen if the call to
2009  * srpt_put_send_iotcx() is delayed because of a higher priority interrupt or
2010  * if IB retransmission causes generation of the send completion to be
2011  * delayed. Incoming information units for which srpt_get_send_ioctx() fails
2012  * are queued on cmd_wait_list. The code below processes these delayed
2013  * requests one at a time.
2014  */
2015 static void srpt_process_send_completion(struct ib_cq *cq,
2016                                          struct srpt_rdma_ch *ch,
2017                                          struct ib_wc *wc)
2018 {
2019         struct srpt_send_ioctx *send_ioctx;
2020         uint32_t index;
2021         enum srpt_opcode opcode;
2022
2023         index = idx_from_wr_id(wc->wr_id);
2024         opcode = opcode_from_wr_id(wc->wr_id);
2025         send_ioctx = ch->ioctx_ring[index];
2026         if (wc->status == IB_WC_SUCCESS) {
2027                 if (opcode == SRPT_SEND)
2028                         srpt_handle_send_comp(ch, send_ioctx);
2029                 else {
2030                         WARN_ON(opcode != SRPT_RDMA_ABORT &&
2031                                 wc->opcode != IB_WC_RDMA_READ);
2032                         srpt_handle_rdma_comp(ch, send_ioctx, opcode);
2033                 }
2034         } else {
2035                 if (opcode == SRPT_SEND) {
2036                         printk(KERN_INFO "sending response for idx %u failed"
2037                                " with status %d\n", index, wc->status);
2038                         srpt_handle_send_err_comp(ch, wc->wr_id);
2039                 } else if (opcode != SRPT_RDMA_MID) {
2040                         printk(KERN_INFO "RDMA t %d for idx %u failed with"
2041                                 " status %d", opcode, index, wc->status);
2042                         srpt_handle_rdma_err_comp(ch, send_ioctx, opcode);
2043                 }
2044         }
2045
2046         while (unlikely(opcode == SRPT_SEND
2047                         && !list_empty(&ch->cmd_wait_list)
2048                         && srpt_get_ch_state(ch) == CH_LIVE
2049                         && (send_ioctx = srpt_get_send_ioctx(ch)) != NULL)) {
2050                 struct srpt_recv_ioctx *recv_ioctx;
2051
2052                 recv_ioctx = list_first_entry(&ch->cmd_wait_list,
2053                                               struct srpt_recv_ioctx,
2054                                               wait_list);
2055                 list_del(&recv_ioctx->wait_list);
2056                 srpt_handle_new_iu(ch, recv_ioctx, send_ioctx);
2057         }
2058 }
2059
2060 static void srpt_process_completion(struct ib_cq *cq, struct srpt_rdma_ch *ch)
2061 {
2062         struct ib_wc *const wc = ch->wc;
2063         int i, n;
2064
2065         WARN_ON(cq != ch->cq);
2066
2067         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
2068         while ((n = ib_poll_cq(cq, ARRAY_SIZE(ch->wc), wc)) > 0) {
2069                 for (i = 0; i < n; i++) {
2070                         if (opcode_from_wr_id(wc[i].wr_id) == SRPT_RECV)
2071                                 srpt_process_rcv_completion(cq, ch, &wc[i]);
2072                         else
2073                                 srpt_process_send_completion(cq, ch, &wc[i]);
2074                 }
2075         }
2076 }
2077
2078 /**
2079  * srpt_completion() - IB completion queue callback function.
2080  *
2081  * Notes:
2082  * - It is guaranteed that a completion handler will never be invoked
2083  *   concurrently on two different CPUs for the same completion queue. See also
2084  *   Documentation/infiniband/core_locking.txt and the implementation of
2085  *   handle_edge_irq() in kernel/irq/chip.c.
2086  * - When threaded IRQs are enabled, completion handlers are invoked in thread
2087  *   context instead of interrupt context.
2088  */
2089 static void srpt_completion(struct ib_cq *cq, void *ctx)
2090 {
2091         struct srpt_rdma_ch *ch = ctx;
2092
2093         wake_up_interruptible(&ch->wait_queue);
2094 }
2095
2096 static int srpt_compl_thread(void *arg)
2097 {
2098         struct srpt_rdma_ch *ch;
2099
2100         /* Hibernation / freezing of the SRPT kernel thread is not supported. */
2101         current->flags |= PF_NOFREEZE;
2102
2103         ch = arg;
2104         BUG_ON(!ch);
2105         printk(KERN_INFO "Session %s: kernel thread %s (PID %d) started\n",
2106                ch->sess_name, ch->thread->comm, current->pid);
2107         while (!kthread_should_stop()) {
2108                 wait_event_interruptible(ch->wait_queue,
2109                         (srpt_process_completion(ch->cq, ch),
2110                          kthread_should_stop()));
2111         }
2112         printk(KERN_INFO "Session %s: kernel thread %s (PID %d) stopped\n",
2113                ch->sess_name, ch->thread->comm, current->pid);
2114         return 0;
2115 }
2116
2117 /**
2118  * srpt_create_ch_ib() - Create receive and send completion queues.
2119  */
2120 static int srpt_create_ch_ib(struct srpt_rdma_ch *ch)
2121 {
2122         struct ib_qp_init_attr *qp_init;
2123         struct srpt_port *sport = ch->sport;
2124         struct srpt_device *sdev = sport->sdev;
2125         u32 srp_sq_size = sport->port_attrib.srp_sq_size;
2126         int ret;
2127
2128         WARN_ON(ch->rq_size < 1);
2129
2130         ret = -ENOMEM;
2131         qp_init = kzalloc(sizeof *qp_init, GFP_KERNEL);
2132         if (!qp_init)
2133                 goto out;
2134
2135         ch->cq = ib_create_cq(sdev->device, srpt_completion, NULL, ch,
2136                               ch->rq_size + srp_sq_size, 0);
2137         if (IS_ERR(ch->cq)) {
2138                 ret = PTR_ERR(ch->cq);
2139                 printk(KERN_ERR "failed to create CQ cqe= %d ret= %d\n",
2140                        ch->rq_size + srp_sq_size, ret);
2141                 goto out;
2142         }
2143
2144         qp_init->qp_context = (void *)ch;
2145         qp_init->event_handler
2146                 = (void(*)(struct ib_event *, void*))srpt_qp_event;
2147         qp_init->send_cq = ch->cq;
2148         qp_init->recv_cq = ch->cq;
2149         qp_init->srq = sdev->srq;
2150         qp_init->sq_sig_type = IB_SIGNAL_REQ_WR;
2151         qp_init->qp_type = IB_QPT_RC;
2152         qp_init->cap.max_send_wr = srp_sq_size;
2153         qp_init->cap.max_send_sge = SRPT_DEF_SG_PER_WQE;
2154
2155         ch->qp = ib_create_qp(sdev->pd, qp_init);
2156         if (IS_ERR(ch->qp)) {
2157                 ret = PTR_ERR(ch->qp);
2158                 printk(KERN_ERR "failed to create_qp ret= %d\n", ret);
2159                 goto err_destroy_cq;
2160         }
2161
2162         atomic_set(&ch->sq_wr_avail, qp_init->cap.max_send_wr);
2163
2164         pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n",
2165                  __func__, ch->cq->cqe, qp_init->cap.max_send_sge,
2166                  qp_init->cap.max_send_wr, ch->cm_id);
2167
2168         ret = srpt_init_ch_qp(ch, ch->qp);
2169         if (ret)
2170                 goto err_destroy_qp;
2171
2172         init_waitqueue_head(&ch->wait_queue);
2173
2174         pr_debug("creating thread for session %s\n", ch->sess_name);
2175
2176         ch->thread = kthread_run(srpt_compl_thread, ch, "ib_srpt_compl");
2177         if (IS_ERR(ch->thread)) {
2178                 printk(KERN_ERR "failed to create kernel thread %ld\n",
2179                        PTR_ERR(ch->thread));
2180                 ch->thread = NULL;
2181                 goto err_destroy_qp;
2182         }
2183
2184 out:
2185         kfree(qp_init);
2186         return ret;
2187
2188 err_destroy_qp:
2189         ib_destroy_qp(ch->qp);
2190 err_destroy_cq:
2191         ib_destroy_cq(ch->cq);
2192         goto out;
2193 }
2194
2195 static void srpt_destroy_ch_ib(struct srpt_rdma_ch *ch)
2196 {
2197         if (ch->thread)
2198                 kthread_stop(ch->thread);
2199
2200         ib_destroy_qp(ch->qp);
2201         ib_destroy_cq(ch->cq);
2202 }
2203
2204 /**
2205  * __srpt_close_ch() - Close an RDMA channel by setting the QP error state.
2206  *
2207  * Reset the QP and make sure all resources associated with the channel will
2208  * be deallocated at an appropriate time.
2209  *
2210  * Note: The caller must hold ch->sport->sdev->spinlock.
2211  */
2212 static void __srpt_close_ch(struct srpt_rdma_ch *ch)
2213 {
2214         struct srpt_device *sdev;
2215         enum rdma_ch_state prev_state;
2216         unsigned long flags;
2217
2218         sdev = ch->sport->sdev;
2219
2220         spin_lock_irqsave(&ch->spinlock, flags);
2221         prev_state = ch->state;
2222         switch (prev_state) {
2223         case CH_CONNECTING:
2224         case CH_LIVE:
2225                 ch->state = CH_DISCONNECTING;
2226                 break;
2227         default:
2228                 break;
2229         }
2230         spin_unlock_irqrestore(&ch->spinlock, flags);
2231
2232         switch (prev_state) {
2233         case CH_CONNECTING:
2234                 ib_send_cm_rej(ch->cm_id, IB_CM_REJ_NO_RESOURCES, NULL, 0,
2235                                NULL, 0);
2236                 /* fall through */
2237         case CH_LIVE:
2238                 if (ib_send_cm_dreq(ch->cm_id, NULL, 0) < 0)
2239                         printk(KERN_ERR "sending CM DREQ failed.\n");
2240                 break;
2241         case CH_DISCONNECTING:
2242                 break;
2243         case CH_DRAINING:
2244         case CH_RELEASING:
2245                 break;
2246         }
2247 }
2248
2249 /**
2250  * srpt_close_ch() - Close an RDMA channel.
2251  */
2252 static void srpt_close_ch(struct srpt_rdma_ch *ch)
2253 {
2254         struct srpt_device *sdev;
2255
2256         sdev = ch->sport->sdev;
2257         spin_lock_irq(&sdev->spinlock);
2258         __srpt_close_ch(ch);
2259         spin_unlock_irq(&sdev->spinlock);
2260 }
2261
2262 /**
2263  * srpt_drain_channel() - Drain a channel by resetting the IB queue pair.
2264  * @cm_id: Pointer to the CM ID of the channel to be drained.
2265  *
2266  * Note: Must be called from inside srpt_cm_handler to avoid a race between
2267  * accessing sdev->spinlock and the call to kfree(sdev) in srpt_remove_one()
2268  * (the caller of srpt_cm_handler holds the cm_id spinlock; srpt_remove_one()
2269  * waits until all target sessions for the associated IB device have been
2270  * unregistered and target session registration involves a call to
2271  * ib_destroy_cm_id(), which locks the cm_id spinlock and hence waits until
2272  * this function has finished).
2273  */
2274 static void srpt_drain_channel(struct ib_cm_id *cm_id)
2275 {
2276         struct srpt_device *sdev;
2277         struct srpt_rdma_ch *ch;
2278         int ret;
2279         bool do_reset = false;
2280
2281         WARN_ON_ONCE(irqs_disabled());
2282
2283         sdev = cm_id->context;
2284         BUG_ON(!sdev);
2285         spin_lock_irq(&sdev->spinlock);
2286         list_for_each_entry(ch, &sdev->rch_list, list) {
2287                 if (ch->cm_id == cm_id) {
2288                         do_reset = srpt_test_and_set_ch_state(ch,
2289                                         CH_CONNECTING, CH_DRAINING) ||
2290                                    srpt_test_and_set_ch_state(ch,
2291                                         CH_LIVE, CH_DRAINING) ||
2292                                    srpt_test_and_set_ch_state(ch,
2293                                         CH_DISCONNECTING, CH_DRAINING);
2294                         break;
2295                 }
2296         }
2297         spin_unlock_irq(&sdev->spinlock);
2298
2299         if (do_reset) {
2300                 ret = srpt_ch_qp_err(ch);
2301                 if (ret < 0)
2302                         printk(KERN_ERR "Setting queue pair in error state"
2303                                " failed: %d\n", ret);
2304         }
2305 }
2306
2307 /**
2308  * srpt_find_channel() - Look up an RDMA channel.
2309  * @cm_id: Pointer to the CM ID of the channel to be looked up.
2310  *
2311  * Return NULL if no matching RDMA channel has been found.
2312  */
2313 static struct srpt_rdma_ch *srpt_find_channel(struct srpt_device *sdev,
2314                                               struct ib_cm_id *cm_id)
2315 {
2316         struct srpt_rdma_ch *ch;
2317         bool found;
2318
2319         WARN_ON_ONCE(irqs_disabled());
2320         BUG_ON(!sdev);
2321
2322         found = false;
2323         spin_lock_irq(&sdev->spinlock);
2324         list_for_each_entry(ch, &sdev->rch_list, list) {
2325                 if (ch->cm_id == cm_id) {
2326                         found = true;
2327                         break;
2328                 }
2329         }
2330         spin_unlock_irq(&sdev->spinlock);
2331
2332         return found ? ch : NULL;
2333 }
2334
2335 /**
2336  * srpt_release_channel() - Release channel resources.
2337  *
2338  * Schedules the actual release because:
2339  * - Calling the ib_destroy_cm_id() call from inside an IB CM callback would
2340  *   trigger a deadlock.
2341  * - It is not safe to call TCM transport_* functions from interrupt context.
2342  */
2343 static void srpt_release_channel(struct srpt_rdma_ch *ch)
2344 {
2345         schedule_work(&ch->release_work);
2346 }
2347
2348 static void srpt_release_channel_work(struct work_struct *w)
2349 {
2350         struct srpt_rdma_ch *ch;
2351         struct srpt_device *sdev;
2352
2353         ch = container_of(w, struct srpt_rdma_ch, release_work);
2354         pr_debug("ch = %p; ch->sess = %p; release_done = %p\n", ch, ch->sess,
2355                  ch->release_done);
2356
2357         sdev = ch->sport->sdev;
2358         BUG_ON(!sdev);
2359
2360         transport_deregister_session_configfs(ch->sess);
2361         transport_deregister_session(ch->sess);
2362         ch->sess = NULL;
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         ib_destroy_cm_id(ch->cm_id);
2375
2376         if (ch->release_done)
2377                 complete(ch->release_done);
2378
2379         wake_up(&sdev->ch_releaseQ);
2380
2381         kfree(ch);
2382 }
2383
2384 static struct srpt_node_acl *__srpt_lookup_acl(struct srpt_port *sport,
2385                                                u8 i_port_id[16])
2386 {
2387         struct srpt_node_acl *nacl;
2388
2389         list_for_each_entry(nacl, &sport->port_acl_list, list)
2390                 if (memcmp(nacl->i_port_id, i_port_id,
2391                            sizeof(nacl->i_port_id)) == 0)
2392                         return nacl;
2393
2394         return NULL;
2395 }
2396
2397 static struct srpt_node_acl *srpt_lookup_acl(struct srpt_port *sport,
2398                                              u8 i_port_id[16])
2399 {
2400         struct srpt_node_acl *nacl;
2401
2402         spin_lock_irq(&sport->port_acl_lock);
2403         nacl = __srpt_lookup_acl(sport, i_port_id);
2404         spin_unlock_irq(&sport->port_acl_lock);
2405
2406         return nacl;
2407 }
2408
2409 /**
2410  * srpt_cm_req_recv() - Process the event IB_CM_REQ_RECEIVED.
2411  *
2412  * Ownership of the cm_id is transferred to the target session if this
2413  * functions returns zero. Otherwise the caller remains the owner of cm_id.
2414  */
2415 static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
2416                             struct ib_cm_req_event_param *param,
2417                             void *private_data)
2418 {
2419         struct srpt_device *sdev = cm_id->context;
2420         struct srpt_port *sport = &sdev->port[param->port - 1];
2421         struct srp_login_req *req;
2422         struct srp_login_rsp *rsp;
2423         struct srp_login_rej *rej;
2424         struct ib_cm_rep_param *rep_param;
2425         struct srpt_rdma_ch *ch, *tmp_ch;
2426         struct srpt_node_acl *nacl;
2427         u32 it_iu_len;
2428         int i;
2429         int ret = 0;
2430
2431         WARN_ON_ONCE(irqs_disabled());
2432
2433         if (WARN_ON(!sdev || !private_data))
2434                 return -EINVAL;
2435
2436         req = (struct srp_login_req *)private_data;
2437
2438         it_iu_len = be32_to_cpu(req->req_it_iu_len);
2439
2440         printk(KERN_INFO "Received SRP_LOGIN_REQ with i_port_id 0x%llx:0x%llx,"
2441                " t_port_id 0x%llx:0x%llx and it_iu_len %d on port %d"
2442                " (guid=0x%llx:0x%llx)\n",
2443                be64_to_cpu(*(__be64 *)&req->initiator_port_id[0]),
2444                be64_to_cpu(*(__be64 *)&req->initiator_port_id[8]),
2445                be64_to_cpu(*(__be64 *)&req->target_port_id[0]),
2446                be64_to_cpu(*(__be64 *)&req->target_port_id[8]),
2447                it_iu_len,
2448                param->port,
2449                be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[0]),
2450                be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[8]));
2451
2452         rsp = kzalloc(sizeof *rsp, GFP_KERNEL);
2453         rej = kzalloc(sizeof *rej, GFP_KERNEL);
2454         rep_param = kzalloc(sizeof *rep_param, GFP_KERNEL);
2455
2456         if (!rsp || !rej || !rep_param) {
2457                 ret = -ENOMEM;
2458                 goto out;
2459         }
2460
2461         if (it_iu_len > srp_max_req_size || it_iu_len < 64) {
2462                 rej->reason = __constant_cpu_to_be32(
2463                                 SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE);
2464                 ret = -EINVAL;
2465                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because its"
2466                        " length (%d bytes) is out of range (%d .. %d)\n",
2467                        it_iu_len, 64, srp_max_req_size);
2468                 goto reject;
2469         }
2470
2471         if (!sport->enabled) {
2472                 rej->reason = __constant_cpu_to_be32(
2473                              SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2474                 ret = -EINVAL;
2475                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because the target port"
2476                        " has not yet been enabled\n");
2477                 goto reject;
2478         }
2479
2480         if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {
2481                 rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN;
2482
2483                 spin_lock_irq(&sdev->spinlock);
2484
2485                 list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) {
2486                         if (!memcmp(ch->i_port_id, req->initiator_port_id, 16)
2487                             && !memcmp(ch->t_port_id, req->target_port_id, 16)
2488                             && param->port == ch->sport->port
2489                             && param->listen_id == ch->sport->sdev->cm_id
2490                             && ch->cm_id) {
2491                                 enum rdma_ch_state ch_state;
2492
2493                                 ch_state = srpt_get_ch_state(ch);
2494                                 if (ch_state != CH_CONNECTING
2495                                     && ch_state != CH_LIVE)
2496                                         continue;
2497
2498                                 /* found an existing channel */
2499                                 pr_debug("Found existing channel %s"
2500                                          " cm_id= %p state= %d\n",
2501                                          ch->sess_name, ch->cm_id, ch_state);
2502
2503                                 __srpt_close_ch(ch);
2504
2505                                 rsp->rsp_flags =
2506                                         SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
2507                         }
2508                 }
2509
2510                 spin_unlock_irq(&sdev->spinlock);
2511
2512         } else
2513                 rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
2514
2515         if (*(__be64 *)req->target_port_id != cpu_to_be64(srpt_service_guid)
2516             || *(__be64 *)(req->target_port_id + 8) !=
2517                cpu_to_be64(srpt_service_guid)) {
2518                 rej->reason = __constant_cpu_to_be32(
2519                                 SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL);
2520                 ret = -ENOMEM;
2521                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because it"
2522                        " has an invalid target port identifier.\n");
2523                 goto reject;
2524         }
2525
2526         ch = kzalloc(sizeof *ch, GFP_KERNEL);
2527         if (!ch) {
2528                 rej->reason = __constant_cpu_to_be32(
2529                                         SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2530                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because no memory.\n");
2531                 ret = -ENOMEM;
2532                 goto reject;
2533         }
2534
2535         INIT_WORK(&ch->release_work, srpt_release_channel_work);
2536         memcpy(ch->i_port_id, req->initiator_port_id, 16);
2537         memcpy(ch->t_port_id, req->target_port_id, 16);
2538         ch->sport = &sdev->port[param->port - 1];
2539         ch->cm_id = cm_id;
2540         /*
2541          * Avoid QUEUE_FULL conditions by limiting the number of buffers used
2542          * for the SRP protocol to the command queue size.
2543          */
2544         ch->rq_size = SRPT_RQ_SIZE;
2545         spin_lock_init(&ch->spinlock);
2546         ch->state = CH_CONNECTING;
2547         INIT_LIST_HEAD(&ch->cmd_wait_list);
2548         ch->rsp_size = ch->sport->port_attrib.srp_max_rsp_size;
2549
2550         ch->ioctx_ring = (struct srpt_send_ioctx **)
2551                 srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,
2552                                       sizeof(*ch->ioctx_ring[0]),
2553                                       ch->rsp_size, DMA_TO_DEVICE);
2554         if (!ch->ioctx_ring)
2555                 goto free_ch;
2556
2557         INIT_LIST_HEAD(&ch->free_list);
2558         for (i = 0; i < ch->rq_size; i++) {
2559                 ch->ioctx_ring[i]->ch = ch;
2560                 list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
2561         }
2562
2563         ret = srpt_create_ch_ib(ch);
2564         if (ret) {
2565                 rej->reason = __constant_cpu_to_be32(
2566                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2567                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because creating"
2568                        " a new RDMA channel failed.\n");
2569                 goto free_ring;
2570         }
2571
2572         ret = srpt_ch_qp_rtr(ch, ch->qp);
2573         if (ret) {
2574                 rej->reason = __constant_cpu_to_be32(
2575                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2576                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because enabling"
2577                        " RTR failed (error code = %d)\n", ret);
2578                 goto destroy_ib;
2579         }
2580         /*
2581          * Use the initator port identifier as the session name.
2582          */
2583         snprintf(ch->sess_name, sizeof(ch->sess_name), "0x%016llx%016llx",
2584                         be64_to_cpu(*(__be64 *)ch->i_port_id),
2585                         be64_to_cpu(*(__be64 *)(ch->i_port_id + 8)));
2586
2587         pr_debug("registering session %s\n", ch->sess_name);
2588
2589         nacl = srpt_lookup_acl(sport, ch->i_port_id);
2590         if (!nacl) {
2591                 printk(KERN_INFO "Rejected login because no ACL has been"
2592                        " configured yet for initiator %s.\n", ch->sess_name);
2593                 rej->reason = __constant_cpu_to_be32(
2594                                 SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED);
2595                 goto destroy_ib;
2596         }
2597
2598         ch->sess = transport_init_session();
2599         if (IS_ERR(ch->sess)) {
2600                 rej->reason = __constant_cpu_to_be32(
2601                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2602                 pr_debug("Failed to create session\n");
2603                 goto deregister_session;
2604         }
2605         ch->sess->se_node_acl = &nacl->nacl;
2606         transport_register_session(&sport->port_tpg_1, &nacl->nacl, ch->sess, ch);
2607
2608         pr_debug("Establish connection sess=%p name=%s cm_id=%p\n", ch->sess,
2609                  ch->sess_name, ch->cm_id);
2610
2611         /* create srp_login_response */
2612         rsp->opcode = SRP_LOGIN_RSP;
2613         rsp->tag = req->tag;
2614         rsp->max_it_iu_len = req->req_it_iu_len;
2615         rsp->max_ti_iu_len = req->req_it_iu_len;
2616         ch->max_ti_iu_len = it_iu_len;
2617         rsp->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT
2618                                               | SRP_BUF_FORMAT_INDIRECT);
2619         rsp->req_lim_delta = cpu_to_be32(ch->rq_size);
2620         atomic_set(&ch->req_lim, ch->rq_size);
2621         atomic_set(&ch->req_lim_delta, 0);
2622
2623         /* create cm reply */
2624         rep_param->qp_num = ch->qp->qp_num;
2625         rep_param->private_data = (void *)rsp;
2626         rep_param->private_data_len = sizeof *rsp;
2627         rep_param->rnr_retry_count = 7;
2628         rep_param->flow_control = 1;
2629         rep_param->failover_accepted = 0;
2630         rep_param->srq = 1;
2631         rep_param->responder_resources = 4;
2632         rep_param->initiator_depth = 4;
2633
2634         ret = ib_send_cm_rep(cm_id, rep_param);
2635         if (ret) {
2636                 printk(KERN_ERR "sending SRP_LOGIN_REQ response failed"
2637                        " (error code = %d)\n", ret);
2638                 goto release_channel;
2639         }
2640
2641         spin_lock_irq(&sdev->spinlock);
2642         list_add_tail(&ch->list, &sdev->rch_list);
2643         spin_unlock_irq(&sdev->spinlock);
2644
2645         goto out;
2646
2647 release_channel:
2648         srpt_set_ch_state(ch, CH_RELEASING);
2649         transport_deregister_session_configfs(ch->sess);
2650
2651 deregister_session:
2652         transport_deregister_session(ch->sess);
2653         ch->sess = NULL;
2654
2655 destroy_ib:
2656         srpt_destroy_ch_ib(ch);
2657
2658 free_ring:
2659         srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
2660                              ch->sport->sdev, ch->rq_size,
2661                              ch->rsp_size, DMA_TO_DEVICE);
2662 free_ch:
2663         kfree(ch);
2664
2665 reject:
2666         rej->opcode = SRP_LOGIN_REJ;
2667         rej->tag = req->tag;
2668         rej->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT
2669                                               | SRP_BUF_FORMAT_INDIRECT);
2670
2671         ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED, NULL, 0,
2672                              (void *)rej, sizeof *rej);
2673
2674 out:
2675         kfree(rep_param);
2676         kfree(rsp);
2677         kfree(rej);
2678
2679         return ret;
2680 }
2681
2682 static void srpt_cm_rej_recv(struct ib_cm_id *cm_id)
2683 {
2684         printk(KERN_INFO "Received IB REJ for cm_id %p.\n", cm_id);
2685         srpt_drain_channel(cm_id);
2686 }
2687
2688 /**
2689  * srpt_cm_rtu_recv() - Process an IB_CM_RTU_RECEIVED or USER_ESTABLISHED event.
2690  *
2691  * An IB_CM_RTU_RECEIVED message indicates that the connection is established
2692  * and that the recipient may begin transmitting (RTU = ready to use).
2693  */
2694 static void srpt_cm_rtu_recv(struct ib_cm_id *cm_id)
2695 {
2696         struct srpt_rdma_ch *ch;
2697         int ret;
2698
2699         ch = srpt_find_channel(cm_id->context, cm_id);
2700         BUG_ON(!ch);
2701
2702         if (srpt_test_and_set_ch_state(ch, CH_CONNECTING, CH_LIVE)) {
2703                 struct srpt_recv_ioctx *ioctx, *ioctx_tmp;
2704
2705                 ret = srpt_ch_qp_rts(ch, ch->qp);
2706
2707                 list_for_each_entry_safe(ioctx, ioctx_tmp, &ch->cmd_wait_list,
2708                                          wait_list) {
2709                         list_del(&ioctx->wait_list);
2710                         srpt_handle_new_iu(ch, ioctx, NULL);
2711                 }
2712                 if (ret)
2713                         srpt_close_ch(ch);
2714         }
2715 }
2716
2717 static void srpt_cm_timewait_exit(struct ib_cm_id *cm_id)
2718 {
2719         printk(KERN_INFO "Received IB TimeWait exit for cm_id %p.\n", cm_id);
2720         srpt_drain_channel(cm_id);
2721 }
2722
2723 static void srpt_cm_rep_error(struct ib_cm_id *cm_id)
2724 {
2725         printk(KERN_INFO "Received IB REP error for cm_id %p.\n", cm_id);
2726         srpt_drain_channel(cm_id);
2727 }
2728
2729 /**
2730  * srpt_cm_dreq_recv() - Process reception of a DREQ message.
2731  */
2732 static void srpt_cm_dreq_recv(struct ib_cm_id *cm_id)
2733 {
2734         struct srpt_rdma_ch *ch;
2735         unsigned long flags;
2736         bool send_drep = false;
2737
2738         ch = srpt_find_channel(cm_id->context, cm_id);
2739         BUG_ON(!ch);
2740
2741         pr_debug("cm_id= %p ch->state= %d\n", cm_id, srpt_get_ch_state(ch));
2742
2743         spin_lock_irqsave(&ch->spinlock, flags);
2744         switch (ch->state) {
2745         case CH_CONNECTING:
2746         case CH_LIVE:
2747                 send_drep = true;
2748                 ch->state = CH_DISCONNECTING;
2749                 break;
2750         case CH_DISCONNECTING:
2751         case CH_DRAINING:
2752         case CH_RELEASING:
2753                 WARN(true, "unexpected channel state %d\n", ch->state);
2754                 break;
2755         }
2756         spin_unlock_irqrestore(&ch->spinlock, flags);
2757
2758         if (send_drep) {
2759                 if (ib_send_cm_drep(ch->cm_id, NULL, 0) < 0)
2760                         printk(KERN_ERR "Sending IB DREP failed.\n");
2761                 printk(KERN_INFO "Received DREQ and sent DREP for session %s.\n",
2762                        ch->sess_name);
2763         }
2764 }
2765
2766 /**
2767  * srpt_cm_drep_recv() - Process reception of a DREP message.
2768  */
2769 static void srpt_cm_drep_recv(struct ib_cm_id *cm_id)
2770 {
2771         printk(KERN_INFO "Received InfiniBand DREP message for cm_id %p.\n",
2772                cm_id);
2773         srpt_drain_channel(cm_id);
2774 }
2775
2776 /**
2777  * srpt_cm_handler() - IB connection manager callback function.
2778  *
2779  * A non-zero return value will cause the caller destroy the CM ID.
2780  *
2781  * Note: srpt_cm_handler() must only return a non-zero value when transferring
2782  * ownership of the cm_id to a channel by srpt_cm_req_recv() failed. Returning
2783  * a non-zero value in any other case will trigger a race with the
2784  * ib_destroy_cm_id() call in srpt_release_channel().
2785  */
2786 static int srpt_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
2787 {
2788         int ret;
2789
2790         ret = 0;
2791         switch (event->event) {
2792         case IB_CM_REQ_RECEIVED:
2793                 ret = srpt_cm_req_recv(cm_id, &event->param.req_rcvd,
2794                                        event->private_data);
2795                 break;
2796         case IB_CM_REJ_RECEIVED:
2797                 srpt_cm_rej_recv(cm_id);
2798                 break;
2799         case IB_CM_RTU_RECEIVED:
2800         case IB_CM_USER_ESTABLISHED:
2801                 srpt_cm_rtu_recv(cm_id);
2802                 break;
2803         case IB_CM_DREQ_RECEIVED:
2804                 srpt_cm_dreq_recv(cm_id);
2805                 break;
2806         case IB_CM_DREP_RECEIVED:
2807                 srpt_cm_drep_recv(cm_id);
2808                 break;
2809         case IB_CM_TIMEWAIT_EXIT:
2810                 srpt_cm_timewait_exit(cm_id);
2811                 break;
2812         case IB_CM_REP_ERROR:
2813                 srpt_cm_rep_error(cm_id);
2814                 break;
2815         case IB_CM_DREQ_ERROR:
2816                 printk(KERN_INFO "Received IB DREQ ERROR event.\n");
2817                 break;
2818         case IB_CM_MRA_RECEIVED:
2819                 printk(KERN_INFO "Received IB MRA event\n");
2820                 break;
2821         default:
2822                 printk(KERN_ERR "received unrecognized IB CM event %d\n",
2823                        event->event);
2824                 break;
2825         }
2826
2827         return ret;
2828 }
2829
2830 /**
2831  * srpt_perform_rdmas() - Perform IB RDMA.
2832  *
2833  * Returns zero upon success or a negative number upon failure.
2834  */
2835 static int srpt_perform_rdmas(struct srpt_rdma_ch *ch,
2836                               struct srpt_send_ioctx *ioctx)
2837 {
2838         struct ib_send_wr wr;
2839         struct ib_send_wr *bad_wr;
2840         struct rdma_iu *riu;
2841         int i;
2842         int ret;
2843         int sq_wr_avail;
2844         enum dma_data_direction dir;
2845         const int n_rdma = ioctx->n_rdma;
2846
2847         dir = ioctx->cmd.data_direction;
2848         if (dir == DMA_TO_DEVICE) {
2849                 /* write */
2850                 ret = -ENOMEM;
2851                 sq_wr_avail = atomic_sub_return(n_rdma, &ch->sq_wr_avail);
2852                 if (sq_wr_avail < 0) {
2853                         printk(KERN_WARNING "IB send queue full (needed %d)\n",
2854                                n_rdma);
2855                         goto out;
2856                 }
2857         }
2858
2859         ioctx->rdma_aborted = false;
2860         ret = 0;
2861         riu = ioctx->rdma_ius;
2862         memset(&wr, 0, sizeof wr);
2863
2864         for (i = 0; i < n_rdma; ++i, ++riu) {
2865                 if (dir == DMA_FROM_DEVICE) {
2866                         wr.opcode = IB_WR_RDMA_WRITE;
2867                         wr.wr_id = encode_wr_id(i == n_rdma - 1 ?
2868                                                 SRPT_RDMA_WRITE_LAST :
2869                                                 SRPT_RDMA_MID,
2870                                                 ioctx->ioctx.index);
2871                 } else {
2872                         wr.opcode = IB_WR_RDMA_READ;
2873                         wr.wr_id = encode_wr_id(i == n_rdma - 1 ?
2874                                                 SRPT_RDMA_READ_LAST :
2875                                                 SRPT_RDMA_MID,
2876                                                 ioctx->ioctx.index);
2877                 }
2878                 wr.next = NULL;
2879                 wr.wr.rdma.remote_addr = riu->raddr;
2880                 wr.wr.rdma.rkey = riu->rkey;
2881                 wr.num_sge = riu->sge_cnt;
2882                 wr.sg_list = riu->sge;
2883
2884                 /* only get completion event for the last rdma write */
2885                 if (i == (n_rdma - 1) && dir == DMA_TO_DEVICE)
2886                         wr.send_flags = IB_SEND_SIGNALED;
2887
2888                 ret = ib_post_send(ch->qp, &wr, &bad_wr);
2889                 if (ret)
2890                         break;
2891         }
2892
2893         if (ret)
2894                 printk(KERN_ERR "%s[%d]: ib_post_send() returned %d for %d/%d",
2895                                  __func__, __LINE__, ret, i, n_rdma);
2896         if (ret && i > 0) {
2897                 wr.num_sge = 0;
2898                 wr.wr_id = encode_wr_id(SRPT_RDMA_ABORT, ioctx->ioctx.index);
2899                 wr.send_flags = IB_SEND_SIGNALED;
2900                 while (ch->state == CH_LIVE &&
2901                         ib_post_send(ch->qp, &wr, &bad_wr) != 0) {
2902                         printk(KERN_INFO "Trying to abort failed RDMA transfer [%d]",
2903                                 ioctx->ioctx.index);
2904                         msleep(1000);
2905                 }
2906                 while (ch->state != CH_RELEASING && !ioctx->rdma_aborted) {
2907                         printk(KERN_INFO "Waiting until RDMA abort finished [%d]",
2908                                 ioctx->ioctx.index);
2909                         msleep(1000);
2910                 }
2911         }
2912 out:
2913         if (unlikely(dir == DMA_TO_DEVICE && ret < 0))
2914                 atomic_add(n_rdma, &ch->sq_wr_avail);
2915         return ret;
2916 }
2917
2918 /**
2919  * srpt_xfer_data() - Start data transfer from initiator to target.
2920  */
2921 static int srpt_xfer_data(struct srpt_rdma_ch *ch,
2922                           struct srpt_send_ioctx *ioctx)
2923 {
2924         int ret;
2925
2926         ret = srpt_map_sg_to_ib_sge(ch, ioctx);
2927         if (ret) {
2928                 printk(KERN_ERR "%s[%d] ret=%d\n", __func__, __LINE__, ret);
2929                 goto out;
2930         }
2931
2932         ret = srpt_perform_rdmas(ch, ioctx);
2933         if (ret) {
2934                 if (ret == -EAGAIN || ret == -ENOMEM)
2935                         printk(KERN_INFO "%s[%d] queue full -- ret=%d\n",
2936                                    __func__, __LINE__, ret);
2937                 else
2938                         printk(KERN_ERR "%s[%d] fatal error -- ret=%d\n",
2939                                __func__, __LINE__, ret);
2940                 goto out_unmap;
2941         }
2942
2943 out:
2944         return ret;
2945 out_unmap:
2946         srpt_unmap_sg_to_ib_sge(ch, ioctx);
2947         goto out;
2948 }
2949
2950 static int srpt_write_pending_status(struct se_cmd *se_cmd)
2951 {
2952         struct srpt_send_ioctx *ioctx;
2953
2954         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
2955         return srpt_get_cmd_state(ioctx) == SRPT_STATE_NEED_DATA;
2956 }
2957
2958 /*
2959  * srpt_write_pending() - Start data transfer from initiator to target (write).
2960  */
2961 static int srpt_write_pending(struct se_cmd *se_cmd)
2962 {
2963         struct srpt_rdma_ch *ch;
2964         struct srpt_send_ioctx *ioctx;
2965         enum srpt_command_state new_state;
2966         enum rdma_ch_state ch_state;
2967         int ret;
2968
2969         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
2970
2971         new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA);
2972         WARN_ON(new_state == SRPT_STATE_DONE);
2973
2974         ch = ioctx->ch;
2975         BUG_ON(!ch);
2976
2977         ch_state = srpt_get_ch_state(ch);
2978         switch (ch_state) {
2979         case CH_CONNECTING:
2980                 WARN(true, "unexpected channel state %d\n", ch_state);
2981                 ret = -EINVAL;
2982                 goto out;
2983         case CH_LIVE:
2984                 break;
2985         case CH_DISCONNECTING:
2986         case CH_DRAINING:
2987         case CH_RELEASING:
2988                 pr_debug("cmd with tag %lld: channel disconnecting\n",
2989                          ioctx->tag);
2990                 srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN);
2991                 ret = -EINVAL;
2992                 goto out;
2993         }
2994         ret = srpt_xfer_data(ch, ioctx);
2995
2996 out:
2997         return ret;
2998 }
2999
3000 static u8 tcm_to_srp_tsk_mgmt_status(const int tcm_mgmt_status)
3001 {
3002         switch (tcm_mgmt_status) {
3003         case TMR_FUNCTION_COMPLETE:
3004                 return SRP_TSK_MGMT_SUCCESS;
3005         case TMR_FUNCTION_REJECTED:
3006                 return SRP_TSK_MGMT_FUNC_NOT_SUPP;
3007         }
3008         return SRP_TSK_MGMT_FAILED;
3009 }
3010
3011 /**
3012  * srpt_queue_response() - Transmits the response to a SCSI command.
3013  *
3014  * Callback function called by the TCM core. Must not block since it can be
3015  * invoked on the context of the IB completion handler.
3016  */
3017 static int srpt_queue_response(struct se_cmd *cmd)
3018 {
3019         struct srpt_rdma_ch *ch;
3020         struct srpt_send_ioctx *ioctx;
3021         enum srpt_command_state state;
3022         unsigned long flags;
3023         int ret;
3024         enum dma_data_direction dir;
3025         int resp_len;
3026         u8 srp_tm_status;
3027
3028         ret = 0;
3029
3030         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
3031         ch = ioctx->ch;
3032         BUG_ON(!ch);
3033
3034         spin_lock_irqsave(&ioctx->spinlock, flags);
3035         state = ioctx->state;
3036         switch (state) {
3037         case SRPT_STATE_NEW:
3038         case SRPT_STATE_DATA_IN:
3039                 ioctx->state = SRPT_STATE_CMD_RSP_SENT;
3040                 break;
3041         case SRPT_STATE_MGMT:
3042                 ioctx->state = SRPT_STATE_MGMT_RSP_SENT;
3043                 break;
3044         default:
3045                 WARN(true, "ch %p; cmd %d: unexpected command state %d\n",
3046                         ch, ioctx->ioctx.index, ioctx->state);
3047                 break;
3048         }
3049         spin_unlock_irqrestore(&ioctx->spinlock, flags);
3050
3051         if (unlikely(transport_check_aborted_status(&ioctx->cmd, false)
3052                      || WARN_ON_ONCE(state == SRPT_STATE_CMD_RSP_SENT))) {
3053                 atomic_inc(&ch->req_lim_delta);
3054                 srpt_abort_cmd(ioctx);
3055                 goto out;
3056         }
3057
3058         dir = ioctx->cmd.data_direction;
3059
3060         /* For read commands, transfer the data to the initiator. */
3061         if (dir == DMA_FROM_DEVICE && ioctx->cmd.data_length &&
3062             !ioctx->queue_status_only) {
3063                 ret = srpt_xfer_data(ch, ioctx);
3064                 if (ret) {
3065                         printk(KERN_ERR "xfer_data failed for tag %llu\n",
3066                                ioctx->tag);
3067                         goto out;
3068                 }
3069         }
3070
3071         if (state != SRPT_STATE_MGMT)
3072                 resp_len = srpt_build_cmd_rsp(ch, ioctx, ioctx->tag,
3073                                               cmd->scsi_status);
3074         else {
3075                 srp_tm_status
3076                         = tcm_to_srp_tsk_mgmt_status(cmd->se_tmr_req->response);
3077                 resp_len = srpt_build_tskmgmt_rsp(ch, ioctx, srp_tm_status,
3078                                                  ioctx->tag);
3079         }
3080         ret = srpt_post_send(ch, ioctx, resp_len);
3081         if (ret) {
3082                 printk(KERN_ERR "sending cmd response failed for tag %llu\n",
3083                        ioctx->tag);
3084                 srpt_unmap_sg_to_ib_sge(ch, ioctx);
3085                 srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
3086                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
3087         }
3088
3089 out:
3090         return ret;
3091 }
3092
3093 static int srpt_queue_status(struct se_cmd *cmd)
3094 {
3095         struct srpt_send_ioctx *ioctx;
3096
3097         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
3098         BUG_ON(ioctx->sense_data != cmd->sense_buffer);
3099         if (cmd->se_cmd_flags &
3100             (SCF_TRANSPORT_TASK_SENSE | SCF_EMULATED_TASK_SENSE))
3101                 WARN_ON(cmd->scsi_status != SAM_STAT_CHECK_CONDITION);
3102         ioctx->queue_status_only = true;
3103         return srpt_queue_response(cmd);
3104 }
3105
3106 static void srpt_refresh_port_work(struct work_struct *work)
3107 {
3108         struct srpt_port *sport = container_of(work, struct srpt_port, work);
3109
3110         srpt_refresh_port(sport);
3111 }
3112
3113 static int srpt_ch_list_empty(struct srpt_device *sdev)
3114 {
3115         int res;
3116
3117         spin_lock_irq(&sdev->spinlock);
3118         res = list_empty(&sdev->rch_list);
3119         spin_unlock_irq(&sdev->spinlock);
3120
3121         return res;
3122 }
3123
3124 /**
3125  * srpt_release_sdev() - Free the channel resources associated with a target.
3126  */
3127 static int srpt_release_sdev(struct srpt_device *sdev)
3128 {
3129         struct srpt_rdma_ch *ch, *tmp_ch;
3130         int res;
3131
3132         WARN_ON_ONCE(irqs_disabled());
3133
3134         BUG_ON(!sdev);
3135
3136         spin_lock_irq(&sdev->spinlock);
3137         list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list)
3138                 __srpt_close_ch(ch);
3139         spin_unlock_irq(&sdev->spinlock);
3140
3141         res = wait_event_interruptible(sdev->ch_releaseQ,
3142                                        srpt_ch_list_empty(sdev));
3143         if (res)
3144                 printk(KERN_ERR "%s: interrupted.\n", __func__);
3145
3146         return 0;
3147 }
3148
3149 static struct srpt_port *__srpt_lookup_port(const char *name)
3150 {
3151         struct ib_device *dev;
3152         struct srpt_device *sdev;
3153         struct srpt_port *sport;
3154         int i;
3155
3156         list_for_each_entry(sdev, &srpt_dev_list, list) {
3157                 dev = sdev->device;
3158                 if (!dev)
3159                         continue;
3160
3161                 for (i = 0; i < dev->phys_port_cnt; i++) {
3162                         sport = &sdev->port[i];
3163
3164                         if (!strcmp(sport->port_guid, name))
3165                                 return sport;
3166                 }
3167         }
3168
3169         return NULL;
3170 }
3171
3172 static struct srpt_port *srpt_lookup_port(const char *name)
3173 {
3174         struct srpt_port *sport;
3175
3176         spin_lock(&srpt_dev_lock);
3177         sport = __srpt_lookup_port(name);
3178         spin_unlock(&srpt_dev_lock);
3179
3180         return sport;
3181 }
3182
3183 /**
3184  * srpt_add_one() - Infiniband device addition callback function.
3185  */
3186 static void srpt_add_one(struct ib_device *device)
3187 {
3188         struct srpt_device *sdev;
3189         struct srpt_port *sport;
3190         struct ib_srq_init_attr srq_attr;
3191         int i;
3192
3193         pr_debug("device = %p, device->dma_ops = %p\n", device,
3194                  device->dma_ops);
3195
3196         sdev = kzalloc(sizeof *sdev, GFP_KERNEL);
3197         if (!sdev)
3198                 goto err;
3199
3200         sdev->device = device;
3201         INIT_LIST_HEAD(&sdev->rch_list);
3202         init_waitqueue_head(&sdev->ch_releaseQ);
3203         spin_lock_init(&sdev->spinlock);
3204
3205         if (ib_query_device(device, &sdev->dev_attr))
3206                 goto free_dev;
3207
3208         sdev->pd = ib_alloc_pd(device);
3209         if (IS_ERR(sdev->pd))
3210                 goto free_dev;
3211
3212         sdev->mr = ib_get_dma_mr(sdev->pd, IB_ACCESS_LOCAL_WRITE);
3213         if (IS_ERR(sdev->mr))
3214                 goto err_pd;
3215
3216         sdev->srq_size = min(srpt_srq_size, sdev->dev_attr.max_srq_wr);
3217
3218         srq_attr.event_handler = srpt_srq_event;
3219         srq_attr.srq_context = (void *)sdev;
3220         srq_attr.attr.max_wr = sdev->srq_size;
3221         srq_attr.attr.max_sge = 1;
3222         srq_attr.attr.srq_limit = 0;
3223
3224         sdev->srq = ib_create_srq(sdev->pd, &srq_attr);
3225         if (IS_ERR(sdev->srq))
3226                 goto err_mr;
3227
3228         pr_debug("%s: create SRQ #wr= %d max_allow=%d dev= %s\n",
3229                  __func__, sdev->srq_size, sdev->dev_attr.max_srq_wr,
3230                  device->name);
3231
3232         if (!srpt_service_guid)
3233                 srpt_service_guid = be64_to_cpu(device->node_guid);
3234
3235         sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev);
3236         if (IS_ERR(sdev->cm_id))
3237                 goto err_srq;
3238
3239         /* print out target login information */
3240         pr_debug("Target login info: id_ext=%016llx,ioc_guid=%016llx,"
3241                  "pkey=ffff,service_id=%016llx\n", srpt_service_guid,
3242                  srpt_service_guid, srpt_service_guid);
3243
3244         /*
3245          * We do not have a consistent service_id (ie. also id_ext of target_id)
3246          * to identify this target. We currently use the guid of the first HCA
3247          * in the system as service_id; therefore, the target_id will change
3248          * if this HCA is gone bad and replaced by different HCA
3249          */
3250         if (ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid), 0, NULL))
3251                 goto err_cm;
3252
3253         INIT_IB_EVENT_HANDLER(&sdev->event_handler, sdev->device,
3254                               srpt_event_handler);
3255         if (ib_register_event_handler(&sdev->event_handler))
3256                 goto err_cm;
3257
3258         sdev->ioctx_ring = (struct srpt_recv_ioctx **)
3259                 srpt_alloc_ioctx_ring(sdev, sdev->srq_size,
3260                                       sizeof(*sdev->ioctx_ring[0]),
3261                                       srp_max_req_size, DMA_FROM_DEVICE);
3262         if (!sdev->ioctx_ring)
3263                 goto err_event;
3264
3265         for (i = 0; i < sdev->srq_size; ++i)
3266                 srpt_post_recv(sdev, sdev->ioctx_ring[i]);
3267
3268         WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));
3269
3270         for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
3271                 sport = &sdev->port[i - 1];
3272                 sport->sdev = sdev;
3273                 sport->port = i;
3274                 sport->port_attrib.srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE;
3275                 sport->port_attrib.srp_max_rsp_size = DEFAULT_MAX_RSP_SIZE;
3276                 sport->port_attrib.srp_sq_size = DEF_SRPT_SQ_SIZE;
3277                 INIT_WORK(&sport->work, srpt_refresh_port_work);
3278                 INIT_LIST_HEAD(&sport->port_acl_list);
3279                 spin_lock_init(&sport->port_acl_lock);
3280
3281                 if (srpt_refresh_port(sport)) {
3282                         printk(KERN_ERR "MAD registration failed for %s-%d.\n",
3283                                srpt_sdev_name(sdev), i);
3284                         goto err_ring;
3285                 }
3286                 snprintf(sport->port_guid, sizeof(sport->port_guid),
3287                         "0x%016llx%016llx",
3288                         be64_to_cpu(sport->gid.global.subnet_prefix),
3289                         be64_to_cpu(sport->gid.global.interface_id));
3290         }
3291
3292         spin_lock(&srpt_dev_lock);
3293         list_add_tail(&sdev->list, &srpt_dev_list);
3294         spin_unlock(&srpt_dev_lock);
3295
3296 out:
3297         ib_set_client_data(device, &srpt_client, sdev);
3298         pr_debug("added %s.\n", device->name);
3299         return;
3300
3301 err_ring:
3302         srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
3303                              sdev->srq_size, srp_max_req_size,
3304                              DMA_FROM_DEVICE);
3305 err_event:
3306         ib_unregister_event_handler(&sdev->event_handler);
3307 err_cm:
3308         ib_destroy_cm_id(sdev->cm_id);
3309 err_srq:
3310         ib_destroy_srq(sdev->srq);
3311 err_mr:
3312         ib_dereg_mr(sdev->mr);
3313 err_pd:
3314         ib_dealloc_pd(sdev->pd);
3315 free_dev:
3316         kfree(sdev);
3317 err:
3318         sdev = NULL;
3319         printk(KERN_INFO "%s(%s) failed.\n", __func__, device->name);
3320         goto out;
3321 }
3322
3323 /**
3324  * srpt_remove_one() - InfiniBand device removal callback function.
3325  */
3326 static void srpt_remove_one(struct ib_device *device)
3327 {
3328         struct srpt_device *sdev;
3329         int i;
3330
3331         sdev = ib_get_client_data(device, &srpt_client);
3332         if (!sdev) {
3333                 printk(KERN_INFO "%s(%s): nothing to do.\n", __func__,
3334                        device->name);
3335                 return;
3336         }
3337
3338         srpt_unregister_mad_agent(sdev);
3339
3340         ib_unregister_event_handler(&sdev->event_handler);
3341
3342         /* Cancel any work queued by the just unregistered IB event handler. */
3343         for (i = 0; i < sdev->device->phys_port_cnt; i++)
3344                 cancel_work_sync(&sdev->port[i].work);
3345
3346         ib_destroy_cm_id(sdev->cm_id);
3347
3348         /*
3349          * Unregistering a target must happen after destroying sdev->cm_id
3350          * such that no new SRP_LOGIN_REQ information units can arrive while
3351          * destroying the target.
3352          */
3353         spin_lock(&srpt_dev_lock);
3354         list_del(&sdev->list);
3355         spin_unlock(&srpt_dev_lock);
3356         srpt_release_sdev(sdev);
3357
3358         ib_destroy_srq(sdev->srq);
3359         ib_dereg_mr(sdev->mr);
3360         ib_dealloc_pd(sdev->pd);
3361
3362         srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
3363                              sdev->srq_size, srp_max_req_size, DMA_FROM_DEVICE);
3364         sdev->ioctx_ring = NULL;
3365         kfree(sdev);
3366 }
3367
3368 static struct ib_client srpt_client = {
3369         .name = DRV_NAME,
3370         .add = srpt_add_one,
3371         .remove = srpt_remove_one
3372 };
3373
3374 static int srpt_check_true(struct se_portal_group *se_tpg)
3375 {
3376         return 1;
3377 }
3378
3379 static int srpt_check_false(struct se_portal_group *se_tpg)
3380 {
3381         return 0;
3382 }
3383
3384 static char *srpt_get_fabric_name(void)
3385 {
3386         return "srpt";
3387 }
3388
3389 static u8 srpt_get_fabric_proto_ident(struct se_portal_group *se_tpg)
3390 {
3391         return SCSI_TRANSPORTID_PROTOCOLID_SRP;
3392 }
3393
3394 static char *srpt_get_fabric_wwn(struct se_portal_group *tpg)
3395 {
3396         struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1);
3397
3398         return sport->port_guid;
3399 }
3400
3401 static u16 srpt_get_tag(struct se_portal_group *tpg)
3402 {
3403         return 1;
3404 }
3405
3406 static u32 srpt_get_default_depth(struct se_portal_group *se_tpg)
3407 {
3408         return 1;
3409 }
3410
3411 static u32 srpt_get_pr_transport_id(struct se_portal_group *se_tpg,
3412                                     struct se_node_acl *se_nacl,
3413                                     struct t10_pr_registration *pr_reg,
3414                                     int *format_code, unsigned char *buf)
3415 {
3416         struct srpt_node_acl *nacl;
3417         struct spc_rdma_transport_id *tr_id;
3418
3419         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3420         tr_id = (void *)buf;
3421         tr_id->protocol_identifier = SCSI_TRANSPORTID_PROTOCOLID_SRP;
3422         memcpy(tr_id->i_port_id, nacl->i_port_id, sizeof(tr_id->i_port_id));
3423         return sizeof(*tr_id);
3424 }
3425
3426 static u32 srpt_get_pr_transport_id_len(struct se_portal_group *se_tpg,
3427                                         struct se_node_acl *se_nacl,
3428                                         struct t10_pr_registration *pr_reg,
3429                                         int *format_code)
3430 {
3431         *format_code = 0;
3432         return sizeof(struct spc_rdma_transport_id);
3433 }
3434
3435 static char *srpt_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
3436                                             const char *buf, u32 *out_tid_len,
3437                                             char **port_nexus_ptr)
3438 {
3439         struct spc_rdma_transport_id *tr_id;
3440
3441         *port_nexus_ptr = NULL;
3442         *out_tid_len = sizeof(struct spc_rdma_transport_id);
3443         tr_id = (void *)buf;
3444         return (char *)tr_id->i_port_id;
3445 }
3446
3447 static struct se_node_acl *srpt_alloc_fabric_acl(struct se_portal_group *se_tpg)
3448 {
3449         struct srpt_node_acl *nacl;
3450
3451         nacl = kzalloc(sizeof(struct srpt_node_acl), GFP_KERNEL);
3452         if (!nacl) {
3453                 printk(KERN_ERR "Unable to alocate struct srpt_node_acl\n");
3454                 return NULL;
3455         }
3456
3457         return &nacl->nacl;
3458 }
3459
3460 static void srpt_release_fabric_acl(struct se_portal_group *se_tpg,
3461                                     struct se_node_acl *se_nacl)
3462 {
3463         struct srpt_node_acl *nacl;
3464
3465         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3466         kfree(nacl);
3467 }
3468
3469 static u32 srpt_tpg_get_inst_index(struct se_portal_group *se_tpg)
3470 {
3471         return 1;
3472 }
3473
3474 static void srpt_release_cmd(struct se_cmd *se_cmd)
3475 {
3476 }
3477
3478 /**
3479  * srpt_shutdown_session() - Whether or not a session may be shut down.
3480  */
3481 static int srpt_shutdown_session(struct se_session *se_sess)
3482 {
3483         return true;
3484 }
3485
3486 /**
3487  * srpt_close_session() - Forcibly close a session.
3488  *
3489  * Callback function invoked by the TCM core to clean up sessions associated
3490  * with a node ACL when the user invokes
3491  * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3492  */
3493 static void srpt_close_session(struct se_session *se_sess)
3494 {
3495         DECLARE_COMPLETION_ONSTACK(release_done);
3496         struct srpt_rdma_ch *ch;
3497         struct srpt_device *sdev;
3498         int res;
3499
3500         ch = se_sess->fabric_sess_ptr;
3501         WARN_ON(ch->sess != se_sess);
3502
3503         pr_debug("ch %p state %d\n", ch, srpt_get_ch_state(ch));
3504
3505         sdev = ch->sport->sdev;
3506         spin_lock_irq(&sdev->spinlock);
3507         BUG_ON(ch->release_done);
3508         ch->release_done = &release_done;
3509         __srpt_close_ch(ch);
3510         spin_unlock_irq(&sdev->spinlock);
3511
3512         res = wait_for_completion_timeout(&release_done, 60 * HZ);
3513         WARN_ON(res <= 0);
3514 }
3515
3516 /**
3517  * To do: Find out whether stop_session() has a meaning for transports
3518  * other than iSCSI.
3519  */
3520 static void srpt_stop_session(struct se_session *se_sess, int sess_sleep,
3521                               int conn_sleep)
3522 {
3523 }
3524
3525 static void srpt_reset_nexus(struct se_session *sess)
3526 {
3527         printk(KERN_ERR "This is the SRP protocol, not iSCSI\n");
3528 }
3529
3530 static int srpt_sess_logged_in(struct se_session *se_sess)
3531 {
3532         return true;
3533 }
3534
3535 /**
3536  * srpt_sess_get_index() - Return the value of scsiAttIntrPortIndex (SCSI-MIB).
3537  *
3538  * A quote from RFC 4455 (SCSI-MIB) about this MIB object:
3539  * This object represents an arbitrary integer used to uniquely identify a
3540  * particular attached remote initiator port to a particular SCSI target port
3541  * within a particular SCSI target device within a particular SCSI instance.
3542  */
3543 static u32 srpt_sess_get_index(struct se_session *se_sess)
3544 {
3545         return 0;
3546 }
3547
3548 static void srpt_set_default_node_attrs(struct se_node_acl *nacl)
3549 {
3550 }
3551
3552 static u32 srpt_get_task_tag(struct se_cmd *se_cmd)
3553 {
3554         struct srpt_send_ioctx *ioctx;
3555
3556         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
3557         return ioctx->tag;
3558 }
3559
3560 /* Note: only used from inside debug printk's by the TCM core. */
3561 static int srpt_get_tcm_cmd_state(struct se_cmd *se_cmd)
3562 {
3563         struct srpt_send_ioctx *ioctx;
3564
3565         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
3566         return srpt_get_cmd_state(ioctx);
3567 }
3568
3569 static u16 srpt_set_fabric_sense_len(struct se_cmd *cmd, u32 sense_length)
3570 {
3571         return 0;
3572 }
3573
3574 static u16 srpt_get_fabric_sense_len(void)
3575 {
3576         return 0;
3577 }
3578
3579 static int srpt_is_state_remove(struct se_cmd *se_cmd)
3580 {
3581         return 0;
3582 }
3583
3584 /**
3585  * srpt_parse_i_port_id() - Parse an initiator port ID.
3586  * @name: ASCII representation of a 128-bit initiator port ID.
3587  * @i_port_id: Binary 128-bit port ID.
3588  */
3589 static int srpt_parse_i_port_id(u8 i_port_id[16], const char *name)
3590 {
3591         const char *p;
3592         unsigned len, count, leading_zero_bytes;
3593         int ret, rc;
3594
3595         p = name;
3596         if (strnicmp(p, "0x", 2) == 0)
3597                 p += 2;
3598         ret = -EINVAL;
3599         len = strlen(p);
3600         if (len % 2)
3601                 goto out;
3602         count = min(len / 2, 16U);
3603         leading_zero_bytes = 16 - count;
3604         memset(i_port_id, 0, leading_zero_bytes);
3605         rc = hex2bin(i_port_id + leading_zero_bytes, p, count);
3606         if (rc < 0)
3607                 pr_debug("hex2bin failed for srpt_parse_i_port_id: %d\n", rc);
3608         ret = 0;
3609 out:
3610         return ret;
3611 }
3612
3613 /*
3614  * configfs callback function invoked for
3615  * mkdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3616  */
3617 static struct se_node_acl *srpt_make_nodeacl(struct se_portal_group *tpg,
3618                                              struct config_group *group,
3619                                              const char *name)
3620 {
3621         struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1);
3622         struct se_node_acl *se_nacl, *se_nacl_new;
3623         struct srpt_node_acl *nacl;
3624         int ret = 0;
3625         u32 nexus_depth = 1;
3626         u8 i_port_id[16];
3627
3628         if (srpt_parse_i_port_id(i_port_id, name) < 0) {
3629                 printk(KERN_ERR "invalid initiator port ID %s\n", name);
3630                 ret = -EINVAL;
3631                 goto err;
3632         }
3633
3634         se_nacl_new = srpt_alloc_fabric_acl(tpg);
3635         if (!se_nacl_new) {
3636                 ret = -ENOMEM;
3637                 goto err;
3638         }
3639         /*
3640          * nacl_new may be released by core_tpg_add_initiator_node_acl()
3641          * when converting a node ACL from demo mode to explict
3642          */
3643         se_nacl = core_tpg_add_initiator_node_acl(tpg, se_nacl_new, name,
3644                                                   nexus_depth);
3645         if (IS_ERR(se_nacl)) {
3646                 ret = PTR_ERR(se_nacl);
3647                 goto err;
3648         }
3649         /* Locate our struct srpt_node_acl and set sdev and i_port_id. */
3650         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3651         memcpy(&nacl->i_port_id[0], &i_port_id[0], 16);
3652         nacl->sport = sport;
3653
3654         spin_lock_irq(&sport->port_acl_lock);
3655         list_add_tail(&nacl->list, &sport->port_acl_list);
3656         spin_unlock_irq(&sport->port_acl_lock);
3657
3658         return se_nacl;
3659 err:
3660         return ERR_PTR(ret);
3661 }
3662
3663 /*
3664  * configfs callback function invoked for
3665  * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3666  */
3667 static void srpt_drop_nodeacl(struct se_node_acl *se_nacl)
3668 {
3669         struct srpt_node_acl *nacl;
3670         struct srpt_device *sdev;
3671         struct srpt_port *sport;
3672
3673         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3674         sport = nacl->sport;
3675         sdev = sport->sdev;
3676         spin_lock_irq(&sport->port_acl_lock);
3677         list_del(&nacl->list);
3678         spin_unlock_irq(&sport->port_acl_lock);
3679         core_tpg_del_initiator_node_acl(&sport->port_tpg_1, se_nacl, 1);
3680         srpt_release_fabric_acl(NULL, se_nacl);
3681 }
3682
3683 static ssize_t srpt_tpg_attrib_show_srp_max_rdma_size(
3684         struct se_portal_group *se_tpg,
3685         char *page)
3686 {
3687         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3688
3689         return sprintf(page, "%u\n", sport->port_attrib.srp_max_rdma_size);
3690 }
3691
3692 static ssize_t srpt_tpg_attrib_store_srp_max_rdma_size(
3693         struct se_portal_group *se_tpg,
3694         const char *page,
3695         size_t count)
3696 {
3697         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3698         unsigned long val;
3699         int ret;
3700
3701         ret = strict_strtoul(page, 0, &val);
3702         if (ret < 0) {
3703                 pr_err("strict_strtoul() failed with ret: %d\n", ret);
3704                 return -EINVAL;
3705         }
3706         if (val > MAX_SRPT_RDMA_SIZE) {
3707                 pr_err("val: %lu exceeds MAX_SRPT_RDMA_SIZE: %d\n", val,
3708                         MAX_SRPT_RDMA_SIZE);
3709                 return -EINVAL;
3710         }
3711         if (val < DEFAULT_MAX_RDMA_SIZE) {
3712                 pr_err("val: %lu smaller than DEFAULT_MAX_RDMA_SIZE: %d\n",
3713                         val, DEFAULT_MAX_RDMA_SIZE);
3714                 return -EINVAL;
3715         }
3716         sport->port_attrib.srp_max_rdma_size = val;
3717
3718         return count;
3719 }
3720
3721 TF_TPG_ATTRIB_ATTR(srpt, srp_max_rdma_size, S_IRUGO | S_IWUSR);
3722
3723 static ssize_t srpt_tpg_attrib_show_srp_max_rsp_size(
3724         struct se_portal_group *se_tpg,
3725         char *page)
3726 {
3727         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3728
3729         return sprintf(page, "%u\n", sport->port_attrib.srp_max_rsp_size);
3730 }
3731
3732 static ssize_t srpt_tpg_attrib_store_srp_max_rsp_size(
3733         struct se_portal_group *se_tpg,
3734         const char *page,
3735         size_t count)
3736 {
3737         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3738         unsigned long val;
3739         int ret;
3740
3741         ret = strict_strtoul(page, 0, &val);
3742         if (ret < 0) {
3743                 pr_err("strict_strtoul() failed with ret: %d\n", ret);
3744                 return -EINVAL;
3745         }
3746         if (val > MAX_SRPT_RSP_SIZE) {
3747                 pr_err("val: %lu exceeds MAX_SRPT_RSP_SIZE: %d\n", val,
3748                         MAX_SRPT_RSP_SIZE);
3749                 return -EINVAL;
3750         }
3751         if (val < MIN_MAX_RSP_SIZE) {
3752                 pr_err("val: %lu smaller than MIN_MAX_RSP_SIZE: %d\n", val,
3753                         MIN_MAX_RSP_SIZE);
3754                 return -EINVAL;
3755         }
3756         sport->port_attrib.srp_max_rsp_size = val;
3757
3758         return count;
3759 }
3760
3761 TF_TPG_ATTRIB_ATTR(srpt, srp_max_rsp_size, S_IRUGO | S_IWUSR);
3762
3763 static ssize_t srpt_tpg_attrib_show_srp_sq_size(
3764         struct se_portal_group *se_tpg,
3765         char *page)
3766 {
3767         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3768
3769         return sprintf(page, "%u\n", sport->port_attrib.srp_sq_size);
3770 }
3771
3772 static ssize_t srpt_tpg_attrib_store_srp_sq_size(
3773         struct se_portal_group *se_tpg,
3774         const char *page,
3775         size_t count)
3776 {
3777         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3778         unsigned long val;
3779         int ret;
3780
3781         ret = strict_strtoul(page, 0, &val);
3782         if (ret < 0) {
3783                 pr_err("strict_strtoul() failed with ret: %d\n", ret);
3784                 return -EINVAL;
3785         }
3786         if (val > MAX_SRPT_SRQ_SIZE) {
3787                 pr_err("val: %lu exceeds MAX_SRPT_SRQ_SIZE: %d\n", val,
3788                         MAX_SRPT_SRQ_SIZE);
3789                 return -EINVAL;
3790         }
3791         if (val < MIN_SRPT_SRQ_SIZE) {
3792                 pr_err("val: %lu smaller than MIN_SRPT_SRQ_SIZE: %d\n", val,
3793                         MIN_SRPT_SRQ_SIZE);
3794                 return -EINVAL;
3795         }
3796         sport->port_attrib.srp_sq_size = val;
3797
3798         return count;
3799 }
3800
3801 TF_TPG_ATTRIB_ATTR(srpt, srp_sq_size, S_IRUGO | S_IWUSR);
3802
3803 static struct configfs_attribute *srpt_tpg_attrib_attrs[] = {
3804         &srpt_tpg_attrib_srp_max_rdma_size.attr,
3805         &srpt_tpg_attrib_srp_max_rsp_size.attr,
3806         &srpt_tpg_attrib_srp_sq_size.attr,
3807         NULL,
3808 };
3809
3810 static ssize_t srpt_tpg_show_enable(
3811         struct se_portal_group *se_tpg,
3812         char *page)
3813 {
3814         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3815
3816         return snprintf(page, PAGE_SIZE, "%d\n", (sport->enabled) ? 1: 0);
3817 }
3818
3819 static ssize_t srpt_tpg_store_enable(
3820         struct se_portal_group *se_tpg,
3821         const char *page,
3822         size_t count)
3823 {
3824         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3825         unsigned long tmp;
3826         int ret;
3827
3828         ret = strict_strtoul(page, 0, &tmp);
3829         if (ret < 0) {
3830                 printk(KERN_ERR "Unable to extract srpt_tpg_store_enable\n");
3831                 return -EINVAL;
3832         }
3833
3834         if ((tmp != 0) && (tmp != 1)) {
3835                 printk(KERN_ERR "Illegal value for srpt_tpg_store_enable: %lu\n", tmp);
3836                 return -EINVAL;
3837         }
3838         if (tmp == 1)
3839                 sport->enabled = true;
3840         else
3841                 sport->enabled = false;
3842
3843         return count;
3844 }
3845
3846 TF_TPG_BASE_ATTR(srpt, enable, S_IRUGO | S_IWUSR);
3847
3848 static struct configfs_attribute *srpt_tpg_attrs[] = {
3849         &srpt_tpg_enable.attr,
3850         NULL,
3851 };
3852
3853 /**
3854  * configfs callback invoked for
3855  * mkdir /sys/kernel/config/target/$driver/$port/$tpg
3856  */
3857 static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn,
3858                                              struct config_group *group,
3859                                              const char *name)
3860 {
3861         struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn);
3862         int res;
3863
3864         /* Initialize sport->port_wwn and sport->port_tpg_1 */
3865         res = core_tpg_register(&srpt_target->tf_ops, &sport->port_wwn,
3866                         &sport->port_tpg_1, sport, TRANSPORT_TPG_TYPE_NORMAL);
3867         if (res)
3868                 return ERR_PTR(res);
3869
3870         return &sport->port_tpg_1;
3871 }
3872
3873 /**
3874  * configfs callback invoked for
3875  * rmdir /sys/kernel/config/target/$driver/$port/$tpg
3876  */
3877 static void srpt_drop_tpg(struct se_portal_group *tpg)
3878 {
3879         struct srpt_port *sport = container_of(tpg,
3880                                 struct srpt_port, port_tpg_1);
3881
3882         sport->enabled = false;
3883         core_tpg_deregister(&sport->port_tpg_1);
3884 }
3885
3886 /**
3887  * configfs callback invoked for
3888  * mkdir /sys/kernel/config/target/$driver/$port
3889  */
3890 static struct se_wwn *srpt_make_tport(struct target_fabric_configfs *tf,
3891                                       struct config_group *group,
3892                                       const char *name)
3893 {
3894         struct srpt_port *sport;
3895         int ret;
3896
3897         sport = srpt_lookup_port(name);
3898         pr_debug("make_tport(%s)\n", name);
3899         ret = -EINVAL;
3900         if (!sport)
3901                 goto err;
3902
3903         return &sport->port_wwn;
3904
3905 err:
3906         return ERR_PTR(ret);
3907 }
3908
3909 /**
3910  * configfs callback invoked for
3911  * rmdir /sys/kernel/config/target/$driver/$port
3912  */
3913 static void srpt_drop_tport(struct se_wwn *wwn)
3914 {
3915         struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn);
3916
3917         pr_debug("drop_tport(%s\n", config_item_name(&sport->port_wwn.wwn_group.cg_item));
3918 }
3919
3920 static ssize_t srpt_wwn_show_attr_version(struct target_fabric_configfs *tf,
3921                                               char *buf)
3922 {
3923         return scnprintf(buf, PAGE_SIZE, "%s\n", DRV_VERSION);
3924 }
3925
3926 TF_WWN_ATTR_RO(srpt, version);
3927
3928 static struct configfs_attribute *srpt_wwn_attrs[] = {
3929         &srpt_wwn_version.attr,
3930         NULL,
3931 };
3932
3933 static struct target_core_fabric_ops srpt_template = {
3934         .get_fabric_name                = srpt_get_fabric_name,
3935         .get_fabric_proto_ident         = srpt_get_fabric_proto_ident,
3936         .tpg_get_wwn                    = srpt_get_fabric_wwn,
3937         .tpg_get_tag                    = srpt_get_tag,
3938         .tpg_get_default_depth          = srpt_get_default_depth,
3939         .tpg_get_pr_transport_id        = srpt_get_pr_transport_id,
3940         .tpg_get_pr_transport_id_len    = srpt_get_pr_transport_id_len,
3941         .tpg_parse_pr_out_transport_id  = srpt_parse_pr_out_transport_id,
3942         .tpg_check_demo_mode            = srpt_check_false,
3943         .tpg_check_demo_mode_cache      = srpt_check_true,
3944         .tpg_check_demo_mode_write_protect = srpt_check_true,
3945         .tpg_check_prod_mode_write_protect = srpt_check_false,
3946         .tpg_alloc_fabric_acl           = srpt_alloc_fabric_acl,
3947         .tpg_release_fabric_acl         = srpt_release_fabric_acl,
3948         .tpg_get_inst_index             = srpt_tpg_get_inst_index,
3949         .release_cmd                    = srpt_release_cmd,
3950         .check_stop_free                = srpt_check_stop_free,
3951         .shutdown_session               = srpt_shutdown_session,
3952         .close_session                  = srpt_close_session,
3953         .stop_session                   = srpt_stop_session,
3954         .fall_back_to_erl0              = srpt_reset_nexus,
3955         .sess_logged_in                 = srpt_sess_logged_in,
3956         .sess_get_index                 = srpt_sess_get_index,
3957         .sess_get_initiator_sid         = NULL,
3958         .write_pending                  = srpt_write_pending,
3959         .write_pending_status           = srpt_write_pending_status,
3960         .set_default_node_attributes    = srpt_set_default_node_attrs,
3961         .get_task_tag                   = srpt_get_task_tag,
3962         .get_cmd_state                  = srpt_get_tcm_cmd_state,
3963         .queue_data_in                  = srpt_queue_response,
3964         .queue_status                   = srpt_queue_status,
3965         .queue_tm_rsp                   = srpt_queue_response,
3966         .get_fabric_sense_len           = srpt_get_fabric_sense_len,
3967         .set_fabric_sense_len           = srpt_set_fabric_sense_len,
3968         .is_state_remove                = srpt_is_state_remove,
3969         /*
3970          * Setup function pointers for generic logic in
3971          * target_core_fabric_configfs.c
3972          */
3973         .fabric_make_wwn                = srpt_make_tport,
3974         .fabric_drop_wwn                = srpt_drop_tport,
3975         .fabric_make_tpg                = srpt_make_tpg,
3976         .fabric_drop_tpg                = srpt_drop_tpg,
3977         .fabric_post_link               = NULL,
3978         .fabric_pre_unlink              = NULL,
3979         .fabric_make_np                 = NULL,
3980         .fabric_drop_np                 = NULL,
3981         .fabric_make_nodeacl            = srpt_make_nodeacl,
3982         .fabric_drop_nodeacl            = srpt_drop_nodeacl,
3983 };
3984
3985 /**
3986  * srpt_init_module() - Kernel module initialization.
3987  *
3988  * Note: Since ib_register_client() registers callback functions, and since at
3989  * least one of these callback functions (srpt_add_one()) calls target core
3990  * functions, this driver must be registered with the target core before
3991  * ib_register_client() is called.
3992  */
3993 static int __init srpt_init_module(void)
3994 {
3995         int ret;
3996
3997         ret = -EINVAL;
3998         if (srp_max_req_size < MIN_MAX_REQ_SIZE) {
3999                 printk(KERN_ERR "invalid value %d for kernel module parameter"
4000                        " srp_max_req_size -- must be at least %d.\n",
4001                        srp_max_req_size, MIN_MAX_REQ_SIZE);
4002                 goto out;
4003         }
4004
4005         if (srpt_srq_size < MIN_SRPT_SRQ_SIZE
4006             || srpt_srq_size > MAX_SRPT_SRQ_SIZE) {
4007                 printk(KERN_ERR "invalid value %d for kernel module parameter"
4008                        " srpt_srq_size -- must be in the range [%d..%d].\n",
4009                        srpt_srq_size, MIN_SRPT_SRQ_SIZE, MAX_SRPT_SRQ_SIZE);
4010                 goto out;
4011         }
4012
4013         srpt_target = target_fabric_configfs_init(THIS_MODULE, "srpt");
4014         if (IS_ERR(srpt_target)) {
4015                 printk(KERN_ERR "couldn't register\n");
4016                 ret = PTR_ERR(srpt_target);
4017                 goto out;
4018         }
4019
4020         srpt_target->tf_ops = srpt_template;
4021
4022         /* Enable SG chaining */
4023         srpt_target->tf_ops.task_sg_chaining = true;
4024
4025         /*
4026          * Set up default attribute lists.
4027          */
4028         srpt_target->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = srpt_wwn_attrs;
4029         srpt_target->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = srpt_tpg_attrs;
4030         srpt_target->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = srpt_tpg_attrib_attrs;
4031         srpt_target->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
4032         srpt_target->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
4033         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;
4034         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
4035         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
4036         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;
4037
4038         ret = target_fabric_configfs_register(srpt_target);
4039         if (ret < 0) {
4040                 printk(KERN_ERR "couldn't register\n");
4041                 goto out_free_target;
4042         }
4043
4044         ret = ib_register_client(&srpt_client);
4045         if (ret) {
4046                 printk(KERN_ERR "couldn't register IB client\n");
4047                 goto out_unregister_target;
4048         }
4049
4050         return 0;
4051
4052 out_unregister_target:
4053         target_fabric_configfs_deregister(srpt_target);
4054         srpt_target = NULL;
4055 out_free_target:
4056         if (srpt_target)
4057                 target_fabric_configfs_free(srpt_target);
4058 out:
4059         return ret;
4060 }
4061
4062 static void __exit srpt_cleanup_module(void)
4063 {
4064         ib_unregister_client(&srpt_client);
4065         target_fabric_configfs_deregister(srpt_target);
4066         srpt_target = NULL;
4067 }
4068
4069 module_init(srpt_init_module);
4070 module_exit(srpt_cleanup_module);