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         ioctx->sg = sg = sg_orig = cmd->t_data_sg;
1103         ioctx->sg_cnt = sg_cnt = cmd->t_data_nents;
1104
1105         count = ib_dma_map_sg(ch->sport->sdev->device, sg, sg_cnt,
1106                               opposite_dma_dir(dir));
1107         if (unlikely(!count))
1108                 return -EAGAIN;
1109
1110         ioctx->mapped_sg_count = count;
1111
1112         if (ioctx->rdma_ius && ioctx->n_rdma_ius)
1113                 nrdma = ioctx->n_rdma_ius;
1114         else {
1115                 nrdma = (count + SRPT_DEF_SG_PER_WQE - 1) / SRPT_DEF_SG_PER_WQE
1116                         + ioctx->n_rbuf;
1117
1118                 ioctx->rdma_ius = kzalloc(nrdma * sizeof *riu, GFP_KERNEL);
1119                 if (!ioctx->rdma_ius)
1120                         goto free_mem;
1121
1122                 ioctx->n_rdma_ius = nrdma;
1123         }
1124
1125         db = ioctx->rbufs;
1126         tsize = cmd->data_length;
1127         dma_len = sg_dma_len(&sg[0]);
1128         riu = ioctx->rdma_ius;
1129
1130         /*
1131          * For each remote desc - calculate the #ib_sge.
1132          * If #ib_sge < SRPT_DEF_SG_PER_WQE per rdma operation then
1133          *      each remote desc rdma_iu is required a rdma wr;
1134          * else
1135          *      we need to allocate extra rdma_iu to carry extra #ib_sge in
1136          *      another rdma wr
1137          */
1138         for (i = 0, j = 0;
1139              j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) {
1140                 rsize = be32_to_cpu(db->len);
1141                 raddr = be64_to_cpu(db->va);
1142                 riu->raddr = raddr;
1143                 riu->rkey = be32_to_cpu(db->key);
1144                 riu->sge_cnt = 0;
1145
1146                 /* calculate how many sge required for this remote_buf */
1147                 while (rsize > 0 && tsize > 0) {
1148
1149                         if (rsize >= dma_len) {
1150                                 tsize -= dma_len;
1151                                 rsize -= dma_len;
1152                                 raddr += dma_len;
1153
1154                                 if (tsize > 0) {
1155                                         ++j;
1156                                         if (j < count) {
1157                                                 sg = sg_next(sg);
1158                                                 dma_len = sg_dma_len(sg);
1159                                         }
1160                                 }
1161                         } else {
1162                                 tsize -= rsize;
1163                                 dma_len -= rsize;
1164                                 rsize = 0;
1165                         }
1166
1167                         ++riu->sge_cnt;
1168
1169                         if (rsize > 0 && riu->sge_cnt == SRPT_DEF_SG_PER_WQE) {
1170                                 ++ioctx->n_rdma;
1171                                 riu->sge =
1172                                     kmalloc(riu->sge_cnt * sizeof *riu->sge,
1173                                             GFP_KERNEL);
1174                                 if (!riu->sge)
1175                                         goto free_mem;
1176
1177                                 ++riu;
1178                                 riu->sge_cnt = 0;
1179                                 riu->raddr = raddr;
1180                                 riu->rkey = be32_to_cpu(db->key);
1181                         }
1182                 }
1183
1184                 ++ioctx->n_rdma;
1185                 riu->sge = kmalloc(riu->sge_cnt * sizeof *riu->sge,
1186                                    GFP_KERNEL);
1187                 if (!riu->sge)
1188                         goto free_mem;
1189         }
1190
1191         db = ioctx->rbufs;
1192         tsize = cmd->data_length;
1193         riu = ioctx->rdma_ius;
1194         sg = sg_orig;
1195         dma_len = sg_dma_len(&sg[0]);
1196         dma_addr = sg_dma_address(&sg[0]);
1197
1198         /* this second loop is really mapped sg_addres to rdma_iu->ib_sge */
1199         for (i = 0, j = 0;
1200              j < count && i < ioctx->n_rbuf && tsize > 0; ++i, ++riu, ++db) {
1201                 rsize = be32_to_cpu(db->len);
1202                 sge = riu->sge;
1203                 k = 0;
1204
1205                 while (rsize > 0 && tsize > 0) {
1206                         sge->addr = dma_addr;
1207                         sge->lkey = ch->sport->sdev->mr->lkey;
1208
1209                         if (rsize >= dma_len) {
1210                                 sge->length =
1211                                         (tsize < dma_len) ? tsize : dma_len;
1212                                 tsize -= dma_len;
1213                                 rsize -= dma_len;
1214
1215                                 if (tsize > 0) {
1216                                         ++j;
1217                                         if (j < count) {
1218                                                 sg = sg_next(sg);
1219                                                 dma_len = sg_dma_len(sg);
1220                                                 dma_addr = sg_dma_address(sg);
1221                                         }
1222                                 }
1223                         } else {
1224                                 sge->length = (tsize < rsize) ? tsize : rsize;
1225                                 tsize -= rsize;
1226                                 dma_len -= rsize;
1227                                 dma_addr += rsize;
1228                                 rsize = 0;
1229                         }
1230
1231                         ++k;
1232                         if (k == riu->sge_cnt && rsize > 0 && tsize > 0) {
1233                                 ++riu;
1234                                 sge = riu->sge;
1235                                 k = 0;
1236                         } else if (rsize > 0 && tsize > 0)
1237                                 ++sge;
1238                 }
1239         }
1240
1241         return 0;
1242
1243 free_mem:
1244         srpt_unmap_sg_to_ib_sge(ch, ioctx);
1245
1246         return -ENOMEM;
1247 }
1248
1249 /**
1250  * srpt_get_send_ioctx() - Obtain an I/O context for sending to the initiator.
1251  */
1252 static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)
1253 {
1254         struct srpt_send_ioctx *ioctx;
1255         unsigned long flags;
1256
1257         BUG_ON(!ch);
1258
1259         ioctx = NULL;
1260         spin_lock_irqsave(&ch->spinlock, flags);
1261         if (!list_empty(&ch->free_list)) {
1262                 ioctx = list_first_entry(&ch->free_list,
1263                                          struct srpt_send_ioctx, free_list);
1264                 list_del(&ioctx->free_list);
1265         }
1266         spin_unlock_irqrestore(&ch->spinlock, flags);
1267
1268         if (!ioctx)
1269                 return ioctx;
1270
1271         BUG_ON(ioctx->ch != ch);
1272         kref_init(&ioctx->kref);
1273         spin_lock_init(&ioctx->spinlock);
1274         ioctx->state = SRPT_STATE_NEW;
1275         ioctx->n_rbuf = 0;
1276         ioctx->rbufs = NULL;
1277         ioctx->n_rdma = 0;
1278         ioctx->n_rdma_ius = 0;
1279         ioctx->rdma_ius = NULL;
1280         ioctx->mapped_sg_count = 0;
1281         init_completion(&ioctx->tx_done);
1282         ioctx->queue_status_only = false;
1283         /*
1284          * transport_init_se_cmd() does not initialize all fields, so do it
1285          * here.
1286          */
1287         memset(&ioctx->cmd, 0, sizeof(ioctx->cmd));
1288         memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data));
1289
1290         return ioctx;
1291 }
1292
1293 /**
1294  * srpt_put_send_ioctx() - Free up resources.
1295  */
1296 static void srpt_put_send_ioctx(struct srpt_send_ioctx *ioctx)
1297 {
1298         struct srpt_rdma_ch *ch;
1299         unsigned long flags;
1300
1301         BUG_ON(!ioctx);
1302         ch = ioctx->ch;
1303         BUG_ON(!ch);
1304
1305         WARN_ON(srpt_get_cmd_state(ioctx) != SRPT_STATE_DONE);
1306
1307         srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx);
1308         transport_generic_free_cmd(&ioctx->cmd, 0);
1309
1310         if (ioctx->n_rbuf > 1) {
1311                 kfree(ioctx->rbufs);
1312                 ioctx->rbufs = NULL;
1313                 ioctx->n_rbuf = 0;
1314         }
1315
1316         spin_lock_irqsave(&ch->spinlock, flags);
1317         list_add(&ioctx->free_list, &ch->free_list);
1318         spin_unlock_irqrestore(&ch->spinlock, flags);
1319 }
1320
1321 static void srpt_put_send_ioctx_kref(struct kref *kref)
1322 {
1323         srpt_put_send_ioctx(container_of(kref, struct srpt_send_ioctx, kref));
1324 }
1325
1326 /**
1327  * srpt_abort_cmd() - Abort a SCSI command.
1328  * @ioctx:   I/O context associated with the SCSI command.
1329  * @context: Preferred execution context.
1330  */
1331 static int srpt_abort_cmd(struct srpt_send_ioctx *ioctx)
1332 {
1333         enum srpt_command_state state;
1334         unsigned long flags;
1335
1336         BUG_ON(!ioctx);
1337
1338         /*
1339          * If the command is in a state where the target core is waiting for
1340          * the ib_srpt driver, change the state to the next state. Changing
1341          * the state of the command from SRPT_STATE_NEED_DATA to
1342          * SRPT_STATE_DATA_IN ensures that srpt_xmit_response() will call this
1343          * function a second time.
1344          */
1345
1346         spin_lock_irqsave(&ioctx->spinlock, flags);
1347         state = ioctx->state;
1348         switch (state) {
1349         case SRPT_STATE_NEED_DATA:
1350                 ioctx->state = SRPT_STATE_DATA_IN;
1351                 break;
1352         case SRPT_STATE_DATA_IN:
1353         case SRPT_STATE_CMD_RSP_SENT:
1354         case SRPT_STATE_MGMT_RSP_SENT:
1355                 ioctx->state = SRPT_STATE_DONE;
1356                 break;
1357         default:
1358                 break;
1359         }
1360         spin_unlock_irqrestore(&ioctx->spinlock, flags);
1361
1362         if (state == SRPT_STATE_DONE)
1363                 goto out;
1364
1365         pr_debug("Aborting cmd with state %d and tag %lld\n", state,
1366                  ioctx->tag);
1367
1368         switch (state) {
1369         case SRPT_STATE_NEW:
1370         case SRPT_STATE_DATA_IN:
1371         case SRPT_STATE_MGMT:
1372                 /*
1373                  * Do nothing - defer abort processing until
1374                  * srpt_queue_response() is invoked.
1375                  */
1376                 WARN_ON(!transport_check_aborted_status(&ioctx->cmd, false));
1377                 break;
1378         case SRPT_STATE_NEED_DATA:
1379                 /* DMA_TO_DEVICE (write) - RDMA read error. */
1380                 spin_lock_irqsave(&ioctx->cmd.t_state_lock, flags);
1381                 ioctx->cmd.transport_state |= CMD_T_LUN_STOP;
1382                 spin_unlock_irqrestore(&ioctx->cmd.t_state_lock, flags);
1383                 transport_generic_handle_data(&ioctx->cmd);
1384                 break;
1385         case SRPT_STATE_CMD_RSP_SENT:
1386                 /*
1387                  * SRP_RSP sending failed or the SRP_RSP send completion has
1388                  * not been received in time.
1389                  */
1390                 srpt_unmap_sg_to_ib_sge(ioctx->ch, ioctx);
1391                 spin_lock_irqsave(&ioctx->cmd.t_state_lock, flags);
1392                 ioctx->cmd.transport_state |= CMD_T_LUN_STOP;
1393                 spin_unlock_irqrestore(&ioctx->cmd.t_state_lock, flags);
1394                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1395                 break;
1396         case SRPT_STATE_MGMT_RSP_SENT:
1397                 srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
1398                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1399                 break;
1400         default:
1401                 WARN_ON("ERROR: unexpected command state");
1402                 break;
1403         }
1404
1405 out:
1406         return state;
1407 }
1408
1409 /**
1410  * srpt_handle_send_err_comp() - Process an IB_WC_SEND error completion.
1411  */
1412 static void srpt_handle_send_err_comp(struct srpt_rdma_ch *ch, u64 wr_id)
1413 {
1414         struct srpt_send_ioctx *ioctx;
1415         enum srpt_command_state state;
1416         struct se_cmd *cmd;
1417         u32 index;
1418
1419         atomic_inc(&ch->sq_wr_avail);
1420
1421         index = idx_from_wr_id(wr_id);
1422         ioctx = ch->ioctx_ring[index];
1423         state = srpt_get_cmd_state(ioctx);
1424         cmd = &ioctx->cmd;
1425
1426         WARN_ON(state != SRPT_STATE_CMD_RSP_SENT
1427                 && state != SRPT_STATE_MGMT_RSP_SENT
1428                 && state != SRPT_STATE_NEED_DATA
1429                 && state != SRPT_STATE_DONE);
1430
1431         /* If SRP_RSP sending failed, undo the ch->req_lim change. */
1432         if (state == SRPT_STATE_CMD_RSP_SENT
1433             || state == SRPT_STATE_MGMT_RSP_SENT)
1434                 atomic_dec(&ch->req_lim);
1435
1436         srpt_abort_cmd(ioctx);
1437 }
1438
1439 /**
1440  * srpt_handle_send_comp() - Process an IB send completion notification.
1441  */
1442 static void srpt_handle_send_comp(struct srpt_rdma_ch *ch,
1443                                   struct srpt_send_ioctx *ioctx)
1444 {
1445         enum srpt_command_state state;
1446
1447         atomic_inc(&ch->sq_wr_avail);
1448
1449         state = srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
1450
1451         if (WARN_ON(state != SRPT_STATE_CMD_RSP_SENT
1452                     && state != SRPT_STATE_MGMT_RSP_SENT
1453                     && state != SRPT_STATE_DONE))
1454                 pr_debug("state = %d\n", state);
1455
1456         if (state != SRPT_STATE_DONE)
1457                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1458         else
1459                 printk(KERN_ERR "IB completion has been received too late for"
1460                        " wr_id = %u.\n", ioctx->ioctx.index);
1461 }
1462
1463 /**
1464  * srpt_handle_rdma_comp() - Process an IB RDMA completion notification.
1465  *
1466  * Note: transport_generic_handle_data() is asynchronous so unmapping the
1467  * data that has been transferred via IB RDMA must be postponed until the
1468  * check_stop_free() callback.
1469  */
1470 static void srpt_handle_rdma_comp(struct srpt_rdma_ch *ch,
1471                                   struct srpt_send_ioctx *ioctx,
1472                                   enum srpt_opcode opcode)
1473 {
1474         WARN_ON(ioctx->n_rdma <= 0);
1475         atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);
1476
1477         if (opcode == SRPT_RDMA_READ_LAST) {
1478                 if (srpt_test_and_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA,
1479                                                 SRPT_STATE_DATA_IN))
1480                         transport_generic_handle_data(&ioctx->cmd);
1481                 else
1482                         printk(KERN_ERR "%s[%d]: wrong state = %d\n", __func__,
1483                                __LINE__, srpt_get_cmd_state(ioctx));
1484         } else if (opcode == SRPT_RDMA_ABORT) {
1485                 ioctx->rdma_aborted = true;
1486         } else {
1487                 WARN(true, "unexpected opcode %d\n", opcode);
1488         }
1489 }
1490
1491 /**
1492  * srpt_handle_rdma_err_comp() - Process an IB RDMA error completion.
1493  */
1494 static void srpt_handle_rdma_err_comp(struct srpt_rdma_ch *ch,
1495                                       struct srpt_send_ioctx *ioctx,
1496                                       enum srpt_opcode opcode)
1497 {
1498         struct se_cmd *cmd;
1499         enum srpt_command_state state;
1500         unsigned long flags;
1501
1502         cmd = &ioctx->cmd;
1503         state = srpt_get_cmd_state(ioctx);
1504         switch (opcode) {
1505         case SRPT_RDMA_READ_LAST:
1506                 if (ioctx->n_rdma <= 0) {
1507                         printk(KERN_ERR "Received invalid RDMA read"
1508                                " error completion with idx %d\n",
1509                                ioctx->ioctx.index);
1510                         break;
1511                 }
1512                 atomic_add(ioctx->n_rdma, &ch->sq_wr_avail);
1513                 if (state == SRPT_STATE_NEED_DATA)
1514                         srpt_abort_cmd(ioctx);
1515                 else
1516                         printk(KERN_ERR "%s[%d]: wrong state = %d\n",
1517                                __func__, __LINE__, state);
1518                 break;
1519         case SRPT_RDMA_WRITE_LAST:
1520                 spin_lock_irqsave(&ioctx->cmd.t_state_lock, flags);
1521                 ioctx->cmd.transport_state |= CMD_T_LUN_STOP;
1522                 spin_unlock_irqrestore(&ioctx->cmd.t_state_lock, flags);
1523                 break;
1524         default:
1525                 printk(KERN_ERR "%s[%d]: opcode = %u\n", __func__,
1526                        __LINE__, opcode);
1527                 break;
1528         }
1529 }
1530
1531 /**
1532  * srpt_build_cmd_rsp() - Build an SRP_RSP response.
1533  * @ch: RDMA channel through which the request has been received.
1534  * @ioctx: I/O context associated with the SRP_CMD request. The response will
1535  *   be built in the buffer ioctx->buf points at and hence this function will
1536  *   overwrite the request data.
1537  * @tag: tag of the request for which this response is being generated.
1538  * @status: value for the STATUS field of the SRP_RSP information unit.
1539  *
1540  * Returns the size in bytes of the SRP_RSP response.
1541  *
1542  * An SRP_RSP response contains a SCSI status or service response. See also
1543  * section 6.9 in the SRP r16a document for the format of an SRP_RSP
1544  * response. See also SPC-2 for more information about sense data.
1545  */
1546 static int srpt_build_cmd_rsp(struct srpt_rdma_ch *ch,
1547                               struct srpt_send_ioctx *ioctx, u64 tag,
1548                               int status)
1549 {
1550         struct srp_rsp *srp_rsp;
1551         const u8 *sense_data;
1552         int sense_data_len, max_sense_len;
1553
1554         /*
1555          * The lowest bit of all SAM-3 status codes is zero (see also
1556          * paragraph 5.3 in SAM-3).
1557          */
1558         WARN_ON(status & 1);
1559
1560         srp_rsp = ioctx->ioctx.buf;
1561         BUG_ON(!srp_rsp);
1562
1563         sense_data = ioctx->sense_data;
1564         sense_data_len = ioctx->cmd.scsi_sense_length;
1565         WARN_ON(sense_data_len > sizeof(ioctx->sense_data));
1566
1567         memset(srp_rsp, 0, sizeof *srp_rsp);
1568         srp_rsp->opcode = SRP_RSP;
1569         srp_rsp->req_lim_delta =
1570                 __constant_cpu_to_be32(1 + atomic_xchg(&ch->req_lim_delta, 0));
1571         srp_rsp->tag = tag;
1572         srp_rsp->status = status;
1573
1574         if (sense_data_len) {
1575                 BUILD_BUG_ON(MIN_MAX_RSP_SIZE <= sizeof(*srp_rsp));
1576                 max_sense_len = ch->max_ti_iu_len - sizeof(*srp_rsp);
1577                 if (sense_data_len > max_sense_len) {
1578                         printk(KERN_WARNING "truncated sense data from %d to %d"
1579                                " bytes\n", sense_data_len, max_sense_len);
1580                         sense_data_len = max_sense_len;
1581                 }
1582
1583                 srp_rsp->flags |= SRP_RSP_FLAG_SNSVALID;
1584                 srp_rsp->sense_data_len = cpu_to_be32(sense_data_len);
1585                 memcpy(srp_rsp + 1, sense_data, sense_data_len);
1586         }
1587
1588         return sizeof(*srp_rsp) + sense_data_len;
1589 }
1590
1591 /**
1592  * srpt_build_tskmgmt_rsp() - Build a task management response.
1593  * @ch:       RDMA channel through which the request has been received.
1594  * @ioctx:    I/O context in which the SRP_RSP response will be built.
1595  * @rsp_code: RSP_CODE that will be stored in the response.
1596  * @tag:      Tag of the request for which this response is being generated.
1597  *
1598  * Returns the size in bytes of the SRP_RSP response.
1599  *
1600  * An SRP_RSP response contains a SCSI status or service response. See also
1601  * section 6.9 in the SRP r16a document for the format of an SRP_RSP
1602  * response.
1603  */
1604 static int srpt_build_tskmgmt_rsp(struct srpt_rdma_ch *ch,
1605                                   struct srpt_send_ioctx *ioctx,
1606                                   u8 rsp_code, u64 tag)
1607 {
1608         struct srp_rsp *srp_rsp;
1609         int resp_data_len;
1610         int resp_len;
1611
1612         resp_data_len = (rsp_code == SRP_TSK_MGMT_SUCCESS) ? 0 : 4;
1613         resp_len = sizeof(*srp_rsp) + resp_data_len;
1614
1615         srp_rsp = ioctx->ioctx.buf;
1616         BUG_ON(!srp_rsp);
1617         memset(srp_rsp, 0, sizeof *srp_rsp);
1618
1619         srp_rsp->opcode = SRP_RSP;
1620         srp_rsp->req_lim_delta = __constant_cpu_to_be32(1
1621                                     + atomic_xchg(&ch->req_lim_delta, 0));
1622         srp_rsp->tag = tag;
1623
1624         if (rsp_code != SRP_TSK_MGMT_SUCCESS) {
1625                 srp_rsp->flags |= SRP_RSP_FLAG_RSPVALID;
1626                 srp_rsp->resp_data_len = cpu_to_be32(resp_data_len);
1627                 srp_rsp->data[3] = rsp_code;
1628         }
1629
1630         return resp_len;
1631 }
1632
1633 #define NO_SUCH_LUN ((uint64_t)-1LL)
1634
1635 /*
1636  * SCSI LUN addressing method. See also SAM-2 and the section about
1637  * eight byte LUNs.
1638  */
1639 enum scsi_lun_addr_method {
1640         SCSI_LUN_ADDR_METHOD_PERIPHERAL   = 0,
1641         SCSI_LUN_ADDR_METHOD_FLAT         = 1,
1642         SCSI_LUN_ADDR_METHOD_LUN          = 2,
1643         SCSI_LUN_ADDR_METHOD_EXTENDED_LUN = 3,
1644 };
1645
1646 /*
1647  * srpt_unpack_lun() - Convert from network LUN to linear LUN.
1648  *
1649  * Convert an 2-byte, 4-byte, 6-byte or 8-byte LUN structure in network byte
1650  * order (big endian) to a linear LUN. Supports three LUN addressing methods:
1651  * peripheral, flat and logical unit. See also SAM-2, section 4.9.4 (page 40).
1652  */
1653 static uint64_t srpt_unpack_lun(const uint8_t *lun, int len)
1654 {
1655         uint64_t res = NO_SUCH_LUN;
1656         int addressing_method;
1657
1658         if (unlikely(len < 2)) {
1659                 printk(KERN_ERR "Illegal LUN length %d, expected 2 bytes or "
1660                        "more", len);
1661                 goto out;
1662         }
1663
1664         switch (len) {
1665         case 8:
1666                 if ((*((__be64 *)lun) &
1667                      __constant_cpu_to_be64(0x0000FFFFFFFFFFFFLL)) != 0)
1668                         goto out_err;
1669                 break;
1670         case 4:
1671                 if (*((__be16 *)&lun[2]) != 0)
1672                         goto out_err;
1673                 break;
1674         case 6:
1675                 if (*((__be32 *)&lun[2]) != 0)
1676                         goto out_err;
1677                 break;
1678         case 2:
1679                 break;
1680         default:
1681                 goto out_err;
1682         }
1683
1684         addressing_method = (*lun) >> 6; /* highest two bits of byte 0 */
1685         switch (addressing_method) {
1686         case SCSI_LUN_ADDR_METHOD_PERIPHERAL:
1687         case SCSI_LUN_ADDR_METHOD_FLAT:
1688         case SCSI_LUN_ADDR_METHOD_LUN:
1689                 res = *(lun + 1) | (((*lun) & 0x3f) << 8);
1690                 break;
1691
1692         case SCSI_LUN_ADDR_METHOD_EXTENDED_LUN:
1693         default:
1694                 printk(KERN_ERR "Unimplemented LUN addressing method %u",
1695                        addressing_method);
1696                 break;
1697         }
1698
1699 out:
1700         return res;
1701
1702 out_err:
1703         printk(KERN_ERR "Support for multi-level LUNs has not yet been"
1704                " implemented");
1705         goto out;
1706 }
1707
1708 static int srpt_check_stop_free(struct se_cmd *cmd)
1709 {
1710         struct srpt_send_ioctx *ioctx;
1711
1712         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
1713         return kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
1714 }
1715
1716 /**
1717  * srpt_handle_cmd() - Process SRP_CMD.
1718  */
1719 static int srpt_handle_cmd(struct srpt_rdma_ch *ch,
1720                            struct srpt_recv_ioctx *recv_ioctx,
1721                            struct srpt_send_ioctx *send_ioctx)
1722 {
1723         struct se_cmd *cmd;
1724         struct srp_cmd *srp_cmd;
1725         uint64_t unpacked_lun;
1726         u64 data_len;
1727         enum dma_data_direction dir;
1728         int ret;
1729
1730         BUG_ON(!send_ioctx);
1731
1732         srp_cmd = recv_ioctx->ioctx.buf;
1733         kref_get(&send_ioctx->kref);
1734         cmd = &send_ioctx->cmd;
1735         send_ioctx->tag = srp_cmd->tag;
1736
1737         switch (srp_cmd->task_attr) {
1738         case SRP_CMD_SIMPLE_Q:
1739                 cmd->sam_task_attr = MSG_SIMPLE_TAG;
1740                 break;
1741         case SRP_CMD_ORDERED_Q:
1742         default:
1743                 cmd->sam_task_attr = MSG_ORDERED_TAG;
1744                 break;
1745         case SRP_CMD_HEAD_OF_Q:
1746                 cmd->sam_task_attr = MSG_HEAD_TAG;
1747                 break;
1748         case SRP_CMD_ACA:
1749                 cmd->sam_task_attr = MSG_ACA_TAG;
1750                 break;
1751         }
1752
1753         ret = srpt_get_desc_tbl(send_ioctx, srp_cmd, &dir, &data_len);
1754         if (ret) {
1755                 printk(KERN_ERR "0x%llx: parsing SRP descriptor table failed.\n",
1756                        srp_cmd->tag);
1757                 cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1758                 cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1759                 kref_put(&send_ioctx->kref, srpt_put_send_ioctx_kref);
1760                 goto send_sense;
1761         }
1762
1763         cmd->data_length = data_len;
1764         cmd->data_direction = dir;
1765         unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_cmd->lun,
1766                                        sizeof(srp_cmd->lun));
1767         if (transport_lookup_cmd_lun(cmd, unpacked_lun) < 0) {
1768                 kref_put(&send_ioctx->kref, srpt_put_send_ioctx_kref);
1769                 goto send_sense;
1770         }
1771         ret = target_setup_cmd_from_cdb(cmd, srp_cmd->cdb);
1772         if (ret < 0) {
1773                 kref_put(&send_ioctx->kref, srpt_put_send_ioctx_kref);
1774                 if (cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT) {
1775                         srpt_queue_status(cmd);
1776                         return 0;
1777                 } else
1778                         goto send_sense;
1779         }
1780
1781         transport_handle_cdb_direct(cmd);
1782         return 0;
1783
1784 send_sense:
1785         transport_send_check_condition_and_sense(cmd, cmd->scsi_sense_reason,
1786                                                  0);
1787         return -1;
1788 }
1789
1790 /**
1791  * srpt_rx_mgmt_fn_tag() - Process a task management function by tag.
1792  * @ch: RDMA channel of the task management request.
1793  * @fn: Task management function to perform.
1794  * @req_tag: Tag of the SRP task management request.
1795  * @mgmt_ioctx: I/O context of the task management request.
1796  *
1797  * Returns zero if the target core will process the task management
1798  * request asynchronously.
1799  *
1800  * Note: It is assumed that the initiator serializes tag-based task management
1801  * requests.
1802  */
1803 static int srpt_rx_mgmt_fn_tag(struct srpt_send_ioctx *ioctx, u64 tag)
1804 {
1805         struct srpt_device *sdev;
1806         struct srpt_rdma_ch *ch;
1807         struct srpt_send_ioctx *target;
1808         int ret, i;
1809
1810         ret = -EINVAL;
1811         ch = ioctx->ch;
1812         BUG_ON(!ch);
1813         BUG_ON(!ch->sport);
1814         sdev = ch->sport->sdev;
1815         BUG_ON(!sdev);
1816         spin_lock_irq(&sdev->spinlock);
1817         for (i = 0; i < ch->rq_size; ++i) {
1818                 target = ch->ioctx_ring[i];
1819                 if (target->cmd.se_lun == ioctx->cmd.se_lun &&
1820                     target->tag == tag &&
1821                     srpt_get_cmd_state(target) != SRPT_STATE_DONE) {
1822                         ret = 0;
1823                         /* now let the target core abort &target->cmd; */
1824                         break;
1825                 }
1826         }
1827         spin_unlock_irq(&sdev->spinlock);
1828         return ret;
1829 }
1830
1831 static int srp_tmr_to_tcm(int fn)
1832 {
1833         switch (fn) {
1834         case SRP_TSK_ABORT_TASK:
1835                 return TMR_ABORT_TASK;
1836         case SRP_TSK_ABORT_TASK_SET:
1837                 return TMR_ABORT_TASK_SET;
1838         case SRP_TSK_CLEAR_TASK_SET:
1839                 return TMR_CLEAR_TASK_SET;
1840         case SRP_TSK_LUN_RESET:
1841                 return TMR_LUN_RESET;
1842         case SRP_TSK_CLEAR_ACA:
1843                 return TMR_CLEAR_ACA;
1844         default:
1845                 return -1;
1846         }
1847 }
1848
1849 /**
1850  * srpt_handle_tsk_mgmt() - Process an SRP_TSK_MGMT information unit.
1851  *
1852  * Returns 0 if and only if the request will be processed by the target core.
1853  *
1854  * For more information about SRP_TSK_MGMT information units, see also section
1855  * 6.7 in the SRP r16a document.
1856  */
1857 static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,
1858                                  struct srpt_recv_ioctx *recv_ioctx,
1859                                  struct srpt_send_ioctx *send_ioctx)
1860 {
1861         struct srp_tsk_mgmt *srp_tsk;
1862         struct se_cmd *cmd;
1863         uint64_t unpacked_lun;
1864         int tcm_tmr;
1865         int res;
1866
1867         BUG_ON(!send_ioctx);
1868
1869         srp_tsk = recv_ioctx->ioctx.buf;
1870         cmd = &send_ioctx->cmd;
1871
1872         pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld"
1873                  " cm_id %p sess %p\n", srp_tsk->tsk_mgmt_func,
1874                  srp_tsk->task_tag, srp_tsk->tag, ch->cm_id, ch->sess);
1875
1876         srpt_set_cmd_state(send_ioctx, SRPT_STATE_MGMT);
1877         send_ioctx->tag = srp_tsk->tag;
1878         tcm_tmr = srp_tmr_to_tcm(srp_tsk->tsk_mgmt_func);
1879         if (tcm_tmr < 0) {
1880                 send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1881                 send_ioctx->cmd.se_tmr_req->response =
1882                         TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
1883                 goto process_tmr;
1884         }
1885         res = core_tmr_alloc_req(cmd, NULL, tcm_tmr, GFP_KERNEL);
1886         if (res < 0) {
1887                 send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1888                 send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED;
1889                 goto process_tmr;
1890         }
1891
1892         unpacked_lun = srpt_unpack_lun((uint8_t *)&srp_tsk->lun,
1893                                        sizeof(srp_tsk->lun));
1894         res = transport_lookup_tmr_lun(&send_ioctx->cmd, unpacked_lun);
1895         if (res) {
1896                 pr_debug("rejecting TMR for LUN %lld\n", unpacked_lun);
1897                 send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1898                 send_ioctx->cmd.se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1899                 goto process_tmr;
1900         }
1901
1902         if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK)
1903                 srpt_rx_mgmt_fn_tag(send_ioctx, srp_tsk->task_tag);
1904
1905 process_tmr:
1906         kref_get(&send_ioctx->kref);
1907         if (!(send_ioctx->cmd.se_cmd_flags & SCF_SCSI_CDB_EXCEPTION))
1908                 transport_generic_handle_tmr(&send_ioctx->cmd);
1909         else
1910                 transport_send_check_condition_and_sense(cmd,
1911                                                 cmd->scsi_sense_reason, 0);
1912
1913 }
1914
1915 /**
1916  * srpt_handle_new_iu() - Process a newly received information unit.
1917  * @ch:    RDMA channel through which the information unit has been received.
1918  * @ioctx: SRPT I/O context associated with the information unit.
1919  */
1920 static void srpt_handle_new_iu(struct srpt_rdma_ch *ch,
1921                                struct srpt_recv_ioctx *recv_ioctx,
1922                                struct srpt_send_ioctx *send_ioctx)
1923 {
1924         struct srp_cmd *srp_cmd;
1925         enum rdma_ch_state ch_state;
1926
1927         BUG_ON(!ch);
1928         BUG_ON(!recv_ioctx);
1929
1930         ib_dma_sync_single_for_cpu(ch->sport->sdev->device,
1931                                    recv_ioctx->ioctx.dma, srp_max_req_size,
1932                                    DMA_FROM_DEVICE);
1933
1934         ch_state = srpt_get_ch_state(ch);
1935         if (unlikely(ch_state == CH_CONNECTING)) {
1936                 list_add_tail(&recv_ioctx->wait_list, &ch->cmd_wait_list);
1937                 goto out;
1938         }
1939
1940         if (unlikely(ch_state != CH_LIVE))
1941                 goto out;
1942
1943         srp_cmd = recv_ioctx->ioctx.buf;
1944         if (srp_cmd->opcode == SRP_CMD || srp_cmd->opcode == SRP_TSK_MGMT) {
1945                 if (!send_ioctx)
1946                         send_ioctx = srpt_get_send_ioctx(ch);
1947                 if (unlikely(!send_ioctx)) {
1948                         list_add_tail(&recv_ioctx->wait_list,
1949                                       &ch->cmd_wait_list);
1950                         goto out;
1951                 }
1952         }
1953
1954         transport_init_se_cmd(&send_ioctx->cmd, &srpt_target->tf_ops, ch->sess,
1955                               0, DMA_NONE, MSG_SIMPLE_TAG,
1956                               send_ioctx->sense_data);
1957
1958         switch (srp_cmd->opcode) {
1959         case SRP_CMD:
1960                 srpt_handle_cmd(ch, recv_ioctx, send_ioctx);
1961                 break;
1962         case SRP_TSK_MGMT:
1963                 srpt_handle_tsk_mgmt(ch, recv_ioctx, send_ioctx);
1964                 break;
1965         case SRP_I_LOGOUT:
1966                 printk(KERN_ERR "Not yet implemented: SRP_I_LOGOUT\n");
1967                 break;
1968         case SRP_CRED_RSP:
1969                 pr_debug("received SRP_CRED_RSP\n");
1970                 break;
1971         case SRP_AER_RSP:
1972                 pr_debug("received SRP_AER_RSP\n");
1973                 break;
1974         case SRP_RSP:
1975                 printk(KERN_ERR "Received SRP_RSP\n");
1976                 break;
1977         default:
1978                 printk(KERN_ERR "received IU with unknown opcode 0x%x\n",
1979                        srp_cmd->opcode);
1980                 break;
1981         }
1982
1983         srpt_post_recv(ch->sport->sdev, recv_ioctx);
1984 out:
1985         return;
1986 }
1987
1988 static void srpt_process_rcv_completion(struct ib_cq *cq,
1989                                         struct srpt_rdma_ch *ch,
1990                                         struct ib_wc *wc)
1991 {
1992         struct srpt_device *sdev = ch->sport->sdev;
1993         struct srpt_recv_ioctx *ioctx;
1994         u32 index;
1995
1996         index = idx_from_wr_id(wc->wr_id);
1997         if (wc->status == IB_WC_SUCCESS) {
1998                 int req_lim;
1999
2000                 req_lim = atomic_dec_return(&ch->req_lim);
2001                 if (unlikely(req_lim < 0))
2002                         printk(KERN_ERR "req_lim = %d < 0\n", req_lim);
2003                 ioctx = sdev->ioctx_ring[index];
2004                 srpt_handle_new_iu(ch, ioctx, NULL);
2005         } else {
2006                 printk(KERN_INFO "receiving failed for idx %u with status %d\n",
2007                        index, wc->status);
2008         }
2009 }
2010
2011 /**
2012  * srpt_process_send_completion() - Process an IB send completion.
2013  *
2014  * Note: Although this has not yet been observed during tests, at least in
2015  * theory it is possible that the srpt_get_send_ioctx() call invoked by
2016  * srpt_handle_new_iu() fails. This is possible because the req_lim_delta
2017  * value in each response is set to one, and it is possible that this response
2018  * makes the initiator send a new request before the send completion for that
2019  * response has been processed. This could e.g. happen if the call to
2020  * srpt_put_send_iotcx() is delayed because of a higher priority interrupt or
2021  * if IB retransmission causes generation of the send completion to be
2022  * delayed. Incoming information units for which srpt_get_send_ioctx() fails
2023  * are queued on cmd_wait_list. The code below processes these delayed
2024  * requests one at a time.
2025  */
2026 static void srpt_process_send_completion(struct ib_cq *cq,
2027                                          struct srpt_rdma_ch *ch,
2028                                          struct ib_wc *wc)
2029 {
2030         struct srpt_send_ioctx *send_ioctx;
2031         uint32_t index;
2032         enum srpt_opcode opcode;
2033
2034         index = idx_from_wr_id(wc->wr_id);
2035         opcode = opcode_from_wr_id(wc->wr_id);
2036         send_ioctx = ch->ioctx_ring[index];
2037         if (wc->status == IB_WC_SUCCESS) {
2038                 if (opcode == SRPT_SEND)
2039                         srpt_handle_send_comp(ch, send_ioctx);
2040                 else {
2041                         WARN_ON(opcode != SRPT_RDMA_ABORT &&
2042                                 wc->opcode != IB_WC_RDMA_READ);
2043                         srpt_handle_rdma_comp(ch, send_ioctx, opcode);
2044                 }
2045         } else {
2046                 if (opcode == SRPT_SEND) {
2047                         printk(KERN_INFO "sending response for idx %u failed"
2048                                " with status %d\n", index, wc->status);
2049                         srpt_handle_send_err_comp(ch, wc->wr_id);
2050                 } else if (opcode != SRPT_RDMA_MID) {
2051                         printk(KERN_INFO "RDMA t %d for idx %u failed with"
2052                                 " status %d", opcode, index, wc->status);
2053                         srpt_handle_rdma_err_comp(ch, send_ioctx, opcode);
2054                 }
2055         }
2056
2057         while (unlikely(opcode == SRPT_SEND
2058                         && !list_empty(&ch->cmd_wait_list)
2059                         && srpt_get_ch_state(ch) == CH_LIVE
2060                         && (send_ioctx = srpt_get_send_ioctx(ch)) != NULL)) {
2061                 struct srpt_recv_ioctx *recv_ioctx;
2062
2063                 recv_ioctx = list_first_entry(&ch->cmd_wait_list,
2064                                               struct srpt_recv_ioctx,
2065                                               wait_list);
2066                 list_del(&recv_ioctx->wait_list);
2067                 srpt_handle_new_iu(ch, recv_ioctx, send_ioctx);
2068         }
2069 }
2070
2071 static void srpt_process_completion(struct ib_cq *cq, struct srpt_rdma_ch *ch)
2072 {
2073         struct ib_wc *const wc = ch->wc;
2074         int i, n;
2075
2076         WARN_ON(cq != ch->cq);
2077
2078         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
2079         while ((n = ib_poll_cq(cq, ARRAY_SIZE(ch->wc), wc)) > 0) {
2080                 for (i = 0; i < n; i++) {
2081                         if (opcode_from_wr_id(wc[i].wr_id) == SRPT_RECV)
2082                                 srpt_process_rcv_completion(cq, ch, &wc[i]);
2083                         else
2084                                 srpt_process_send_completion(cq, ch, &wc[i]);
2085                 }
2086         }
2087 }
2088
2089 /**
2090  * srpt_completion() - IB completion queue callback function.
2091  *
2092  * Notes:
2093  * - It is guaranteed that a completion handler will never be invoked
2094  *   concurrently on two different CPUs for the same completion queue. See also
2095  *   Documentation/infiniband/core_locking.txt and the implementation of
2096  *   handle_edge_irq() in kernel/irq/chip.c.
2097  * - When threaded IRQs are enabled, completion handlers are invoked in thread
2098  *   context instead of interrupt context.
2099  */
2100 static void srpt_completion(struct ib_cq *cq, void *ctx)
2101 {
2102         struct srpt_rdma_ch *ch = ctx;
2103
2104         wake_up_interruptible(&ch->wait_queue);
2105 }
2106
2107 static int srpt_compl_thread(void *arg)
2108 {
2109         struct srpt_rdma_ch *ch;
2110
2111         /* Hibernation / freezing of the SRPT kernel thread is not supported. */
2112         current->flags |= PF_NOFREEZE;
2113
2114         ch = arg;
2115         BUG_ON(!ch);
2116         printk(KERN_INFO "Session %s: kernel thread %s (PID %d) started\n",
2117                ch->sess_name, ch->thread->comm, current->pid);
2118         while (!kthread_should_stop()) {
2119                 wait_event_interruptible(ch->wait_queue,
2120                         (srpt_process_completion(ch->cq, ch),
2121                          kthread_should_stop()));
2122         }
2123         printk(KERN_INFO "Session %s: kernel thread %s (PID %d) stopped\n",
2124                ch->sess_name, ch->thread->comm, current->pid);
2125         return 0;
2126 }
2127
2128 /**
2129  * srpt_create_ch_ib() - Create receive and send completion queues.
2130  */
2131 static int srpt_create_ch_ib(struct srpt_rdma_ch *ch)
2132 {
2133         struct ib_qp_init_attr *qp_init;
2134         struct srpt_port *sport = ch->sport;
2135         struct srpt_device *sdev = sport->sdev;
2136         u32 srp_sq_size = sport->port_attrib.srp_sq_size;
2137         int ret;
2138
2139         WARN_ON(ch->rq_size < 1);
2140
2141         ret = -ENOMEM;
2142         qp_init = kzalloc(sizeof *qp_init, GFP_KERNEL);
2143         if (!qp_init)
2144                 goto out;
2145
2146         ch->cq = ib_create_cq(sdev->device, srpt_completion, NULL, ch,
2147                               ch->rq_size + srp_sq_size, 0);
2148         if (IS_ERR(ch->cq)) {
2149                 ret = PTR_ERR(ch->cq);
2150                 printk(KERN_ERR "failed to create CQ cqe= %d ret= %d\n",
2151                        ch->rq_size + srp_sq_size, ret);
2152                 goto out;
2153         }
2154
2155         qp_init->qp_context = (void *)ch;
2156         qp_init->event_handler
2157                 = (void(*)(struct ib_event *, void*))srpt_qp_event;
2158         qp_init->send_cq = ch->cq;
2159         qp_init->recv_cq = ch->cq;
2160         qp_init->srq = sdev->srq;
2161         qp_init->sq_sig_type = IB_SIGNAL_REQ_WR;
2162         qp_init->qp_type = IB_QPT_RC;
2163         qp_init->cap.max_send_wr = srp_sq_size;
2164         qp_init->cap.max_send_sge = SRPT_DEF_SG_PER_WQE;
2165
2166         ch->qp = ib_create_qp(sdev->pd, qp_init);
2167         if (IS_ERR(ch->qp)) {
2168                 ret = PTR_ERR(ch->qp);
2169                 printk(KERN_ERR "failed to create_qp ret= %d\n", ret);
2170                 goto err_destroy_cq;
2171         }
2172
2173         atomic_set(&ch->sq_wr_avail, qp_init->cap.max_send_wr);
2174
2175         pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n",
2176                  __func__, ch->cq->cqe, qp_init->cap.max_send_sge,
2177                  qp_init->cap.max_send_wr, ch->cm_id);
2178
2179         ret = srpt_init_ch_qp(ch, ch->qp);
2180         if (ret)
2181                 goto err_destroy_qp;
2182
2183         init_waitqueue_head(&ch->wait_queue);
2184
2185         pr_debug("creating thread for session %s\n", ch->sess_name);
2186
2187         ch->thread = kthread_run(srpt_compl_thread, ch, "ib_srpt_compl");
2188         if (IS_ERR(ch->thread)) {
2189                 printk(KERN_ERR "failed to create kernel thread %ld\n",
2190                        PTR_ERR(ch->thread));
2191                 ch->thread = NULL;
2192                 goto err_destroy_qp;
2193         }
2194
2195 out:
2196         kfree(qp_init);
2197         return ret;
2198
2199 err_destroy_qp:
2200         ib_destroy_qp(ch->qp);
2201 err_destroy_cq:
2202         ib_destroy_cq(ch->cq);
2203         goto out;
2204 }
2205
2206 static void srpt_destroy_ch_ib(struct srpt_rdma_ch *ch)
2207 {
2208         if (ch->thread)
2209                 kthread_stop(ch->thread);
2210
2211         ib_destroy_qp(ch->qp);
2212         ib_destroy_cq(ch->cq);
2213 }
2214
2215 /**
2216  * __srpt_close_ch() - Close an RDMA channel by setting the QP error state.
2217  *
2218  * Reset the QP and make sure all resources associated with the channel will
2219  * be deallocated at an appropriate time.
2220  *
2221  * Note: The caller must hold ch->sport->sdev->spinlock.
2222  */
2223 static void __srpt_close_ch(struct srpt_rdma_ch *ch)
2224 {
2225         struct srpt_device *sdev;
2226         enum rdma_ch_state prev_state;
2227         unsigned long flags;
2228
2229         sdev = ch->sport->sdev;
2230
2231         spin_lock_irqsave(&ch->spinlock, flags);
2232         prev_state = ch->state;
2233         switch (prev_state) {
2234         case CH_CONNECTING:
2235         case CH_LIVE:
2236                 ch->state = CH_DISCONNECTING;
2237                 break;
2238         default:
2239                 break;
2240         }
2241         spin_unlock_irqrestore(&ch->spinlock, flags);
2242
2243         switch (prev_state) {
2244         case CH_CONNECTING:
2245                 ib_send_cm_rej(ch->cm_id, IB_CM_REJ_NO_RESOURCES, NULL, 0,
2246                                NULL, 0);
2247                 /* fall through */
2248         case CH_LIVE:
2249                 if (ib_send_cm_dreq(ch->cm_id, NULL, 0) < 0)
2250                         printk(KERN_ERR "sending CM DREQ failed.\n");
2251                 break;
2252         case CH_DISCONNECTING:
2253                 break;
2254         case CH_DRAINING:
2255         case CH_RELEASING:
2256                 break;
2257         }
2258 }
2259
2260 /**
2261  * srpt_close_ch() - Close an RDMA channel.
2262  */
2263 static void srpt_close_ch(struct srpt_rdma_ch *ch)
2264 {
2265         struct srpt_device *sdev;
2266
2267         sdev = ch->sport->sdev;
2268         spin_lock_irq(&sdev->spinlock);
2269         __srpt_close_ch(ch);
2270         spin_unlock_irq(&sdev->spinlock);
2271 }
2272
2273 /**
2274  * srpt_drain_channel() - Drain a channel by resetting the IB queue pair.
2275  * @cm_id: Pointer to the CM ID of the channel to be drained.
2276  *
2277  * Note: Must be called from inside srpt_cm_handler to avoid a race between
2278  * accessing sdev->spinlock and the call to kfree(sdev) in srpt_remove_one()
2279  * (the caller of srpt_cm_handler holds the cm_id spinlock; srpt_remove_one()
2280  * waits until all target sessions for the associated IB device have been
2281  * unregistered and target session registration involves a call to
2282  * ib_destroy_cm_id(), which locks the cm_id spinlock and hence waits until
2283  * this function has finished).
2284  */
2285 static void srpt_drain_channel(struct ib_cm_id *cm_id)
2286 {
2287         struct srpt_device *sdev;
2288         struct srpt_rdma_ch *ch;
2289         int ret;
2290         bool do_reset = false;
2291
2292         WARN_ON_ONCE(irqs_disabled());
2293
2294         sdev = cm_id->context;
2295         BUG_ON(!sdev);
2296         spin_lock_irq(&sdev->spinlock);
2297         list_for_each_entry(ch, &sdev->rch_list, list) {
2298                 if (ch->cm_id == cm_id) {
2299                         do_reset = srpt_test_and_set_ch_state(ch,
2300                                         CH_CONNECTING, CH_DRAINING) ||
2301                                    srpt_test_and_set_ch_state(ch,
2302                                         CH_LIVE, CH_DRAINING) ||
2303                                    srpt_test_and_set_ch_state(ch,
2304                                         CH_DISCONNECTING, CH_DRAINING);
2305                         break;
2306                 }
2307         }
2308         spin_unlock_irq(&sdev->spinlock);
2309
2310         if (do_reset) {
2311                 ret = srpt_ch_qp_err(ch);
2312                 if (ret < 0)
2313                         printk(KERN_ERR "Setting queue pair in error state"
2314                                " failed: %d\n", ret);
2315         }
2316 }
2317
2318 /**
2319  * srpt_find_channel() - Look up an RDMA channel.
2320  * @cm_id: Pointer to the CM ID of the channel to be looked up.
2321  *
2322  * Return NULL if no matching RDMA channel has been found.
2323  */
2324 static struct srpt_rdma_ch *srpt_find_channel(struct srpt_device *sdev,
2325                                               struct ib_cm_id *cm_id)
2326 {
2327         struct srpt_rdma_ch *ch;
2328         bool found;
2329
2330         WARN_ON_ONCE(irqs_disabled());
2331         BUG_ON(!sdev);
2332
2333         found = false;
2334         spin_lock_irq(&sdev->spinlock);
2335         list_for_each_entry(ch, &sdev->rch_list, list) {
2336                 if (ch->cm_id == cm_id) {
2337                         found = true;
2338                         break;
2339                 }
2340         }
2341         spin_unlock_irq(&sdev->spinlock);
2342
2343         return found ? ch : NULL;
2344 }
2345
2346 /**
2347  * srpt_release_channel() - Release channel resources.
2348  *
2349  * Schedules the actual release because:
2350  * - Calling the ib_destroy_cm_id() call from inside an IB CM callback would
2351  *   trigger a deadlock.
2352  * - It is not safe to call TCM transport_* functions from interrupt context.
2353  */
2354 static void srpt_release_channel(struct srpt_rdma_ch *ch)
2355 {
2356         schedule_work(&ch->release_work);
2357 }
2358
2359 static void srpt_release_channel_work(struct work_struct *w)
2360 {
2361         struct srpt_rdma_ch *ch;
2362         struct srpt_device *sdev;
2363
2364         ch = container_of(w, struct srpt_rdma_ch, release_work);
2365         pr_debug("ch = %p; ch->sess = %p; release_done = %p\n", ch, ch->sess,
2366                  ch->release_done);
2367
2368         sdev = ch->sport->sdev;
2369         BUG_ON(!sdev);
2370
2371         transport_deregister_session_configfs(ch->sess);
2372         transport_deregister_session(ch->sess);
2373         ch->sess = NULL;
2374
2375         srpt_destroy_ch_ib(ch);
2376
2377         srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
2378                              ch->sport->sdev, ch->rq_size,
2379                              ch->rsp_size, DMA_TO_DEVICE);
2380
2381         spin_lock_irq(&sdev->spinlock);
2382         list_del(&ch->list);
2383         spin_unlock_irq(&sdev->spinlock);
2384
2385         ib_destroy_cm_id(ch->cm_id);
2386
2387         if (ch->release_done)
2388                 complete(ch->release_done);
2389
2390         wake_up(&sdev->ch_releaseQ);
2391
2392         kfree(ch);
2393 }
2394
2395 static struct srpt_node_acl *__srpt_lookup_acl(struct srpt_port *sport,
2396                                                u8 i_port_id[16])
2397 {
2398         struct srpt_node_acl *nacl;
2399
2400         list_for_each_entry(nacl, &sport->port_acl_list, list)
2401                 if (memcmp(nacl->i_port_id, i_port_id,
2402                            sizeof(nacl->i_port_id)) == 0)
2403                         return nacl;
2404
2405         return NULL;
2406 }
2407
2408 static struct srpt_node_acl *srpt_lookup_acl(struct srpt_port *sport,
2409                                              u8 i_port_id[16])
2410 {
2411         struct srpt_node_acl *nacl;
2412
2413         spin_lock_irq(&sport->port_acl_lock);
2414         nacl = __srpt_lookup_acl(sport, i_port_id);
2415         spin_unlock_irq(&sport->port_acl_lock);
2416
2417         return nacl;
2418 }
2419
2420 /**
2421  * srpt_cm_req_recv() - Process the event IB_CM_REQ_RECEIVED.
2422  *
2423  * Ownership of the cm_id is transferred to the target session if this
2424  * functions returns zero. Otherwise the caller remains the owner of cm_id.
2425  */
2426 static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
2427                             struct ib_cm_req_event_param *param,
2428                             void *private_data)
2429 {
2430         struct srpt_device *sdev = cm_id->context;
2431         struct srpt_port *sport = &sdev->port[param->port - 1];
2432         struct srp_login_req *req;
2433         struct srp_login_rsp *rsp;
2434         struct srp_login_rej *rej;
2435         struct ib_cm_rep_param *rep_param;
2436         struct srpt_rdma_ch *ch, *tmp_ch;
2437         struct srpt_node_acl *nacl;
2438         u32 it_iu_len;
2439         int i;
2440         int ret = 0;
2441
2442         WARN_ON_ONCE(irqs_disabled());
2443
2444         if (WARN_ON(!sdev || !private_data))
2445                 return -EINVAL;
2446
2447         req = (struct srp_login_req *)private_data;
2448
2449         it_iu_len = be32_to_cpu(req->req_it_iu_len);
2450
2451         printk(KERN_INFO "Received SRP_LOGIN_REQ with i_port_id 0x%llx:0x%llx,"
2452                " t_port_id 0x%llx:0x%llx and it_iu_len %d on port %d"
2453                " (guid=0x%llx:0x%llx)\n",
2454                be64_to_cpu(*(__be64 *)&req->initiator_port_id[0]),
2455                be64_to_cpu(*(__be64 *)&req->initiator_port_id[8]),
2456                be64_to_cpu(*(__be64 *)&req->target_port_id[0]),
2457                be64_to_cpu(*(__be64 *)&req->target_port_id[8]),
2458                it_iu_len,
2459                param->port,
2460                be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[0]),
2461                be64_to_cpu(*(__be64 *)&sdev->port[param->port - 1].gid.raw[8]));
2462
2463         rsp = kzalloc(sizeof *rsp, GFP_KERNEL);
2464         rej = kzalloc(sizeof *rej, GFP_KERNEL);
2465         rep_param = kzalloc(sizeof *rep_param, GFP_KERNEL);
2466
2467         if (!rsp || !rej || !rep_param) {
2468                 ret = -ENOMEM;
2469                 goto out;
2470         }
2471
2472         if (it_iu_len > srp_max_req_size || it_iu_len < 64) {
2473                 rej->reason = __constant_cpu_to_be32(
2474                                 SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE);
2475                 ret = -EINVAL;
2476                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because its"
2477                        " length (%d bytes) is out of range (%d .. %d)\n",
2478                        it_iu_len, 64, srp_max_req_size);
2479                 goto reject;
2480         }
2481
2482         if (!sport->enabled) {
2483                 rej->reason = __constant_cpu_to_be32(
2484                              SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2485                 ret = -EINVAL;
2486                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because the target port"
2487                        " has not yet been enabled\n");
2488                 goto reject;
2489         }
2490
2491         if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {
2492                 rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN;
2493
2494                 spin_lock_irq(&sdev->spinlock);
2495
2496                 list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list) {
2497                         if (!memcmp(ch->i_port_id, req->initiator_port_id, 16)
2498                             && !memcmp(ch->t_port_id, req->target_port_id, 16)
2499                             && param->port == ch->sport->port
2500                             && param->listen_id == ch->sport->sdev->cm_id
2501                             && ch->cm_id) {
2502                                 enum rdma_ch_state ch_state;
2503
2504                                 ch_state = srpt_get_ch_state(ch);
2505                                 if (ch_state != CH_CONNECTING
2506                                     && ch_state != CH_LIVE)
2507                                         continue;
2508
2509                                 /* found an existing channel */
2510                                 pr_debug("Found existing channel %s"
2511                                          " cm_id= %p state= %d\n",
2512                                          ch->sess_name, ch->cm_id, ch_state);
2513
2514                                 __srpt_close_ch(ch);
2515
2516                                 rsp->rsp_flags =
2517                                         SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
2518                         }
2519                 }
2520
2521                 spin_unlock_irq(&sdev->spinlock);
2522
2523         } else
2524                 rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
2525
2526         if (*(__be64 *)req->target_port_id != cpu_to_be64(srpt_service_guid)
2527             || *(__be64 *)(req->target_port_id + 8) !=
2528                cpu_to_be64(srpt_service_guid)) {
2529                 rej->reason = __constant_cpu_to_be32(
2530                                 SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL);
2531                 ret = -ENOMEM;
2532                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because it"
2533                        " has an invalid target port identifier.\n");
2534                 goto reject;
2535         }
2536
2537         ch = kzalloc(sizeof *ch, GFP_KERNEL);
2538         if (!ch) {
2539                 rej->reason = __constant_cpu_to_be32(
2540                                         SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2541                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because no memory.\n");
2542                 ret = -ENOMEM;
2543                 goto reject;
2544         }
2545
2546         INIT_WORK(&ch->release_work, srpt_release_channel_work);
2547         memcpy(ch->i_port_id, req->initiator_port_id, 16);
2548         memcpy(ch->t_port_id, req->target_port_id, 16);
2549         ch->sport = &sdev->port[param->port - 1];
2550         ch->cm_id = cm_id;
2551         /*
2552          * Avoid QUEUE_FULL conditions by limiting the number of buffers used
2553          * for the SRP protocol to the command queue size.
2554          */
2555         ch->rq_size = SRPT_RQ_SIZE;
2556         spin_lock_init(&ch->spinlock);
2557         ch->state = CH_CONNECTING;
2558         INIT_LIST_HEAD(&ch->cmd_wait_list);
2559         ch->rsp_size = ch->sport->port_attrib.srp_max_rsp_size;
2560
2561         ch->ioctx_ring = (struct srpt_send_ioctx **)
2562                 srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,
2563                                       sizeof(*ch->ioctx_ring[0]),
2564                                       ch->rsp_size, DMA_TO_DEVICE);
2565         if (!ch->ioctx_ring)
2566                 goto free_ch;
2567
2568         INIT_LIST_HEAD(&ch->free_list);
2569         for (i = 0; i < ch->rq_size; i++) {
2570                 ch->ioctx_ring[i]->ch = ch;
2571                 list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
2572         }
2573
2574         ret = srpt_create_ch_ib(ch);
2575         if (ret) {
2576                 rej->reason = __constant_cpu_to_be32(
2577                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2578                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because creating"
2579                        " a new RDMA channel failed.\n");
2580                 goto free_ring;
2581         }
2582
2583         ret = srpt_ch_qp_rtr(ch, ch->qp);
2584         if (ret) {
2585                 rej->reason = __constant_cpu_to_be32(
2586                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2587                 printk(KERN_ERR "rejected SRP_LOGIN_REQ because enabling"
2588                        " RTR failed (error code = %d)\n", ret);
2589                 goto destroy_ib;
2590         }
2591         /*
2592          * Use the initator port identifier as the session name.
2593          */
2594         snprintf(ch->sess_name, sizeof(ch->sess_name), "0x%016llx%016llx",
2595                         be64_to_cpu(*(__be64 *)ch->i_port_id),
2596                         be64_to_cpu(*(__be64 *)(ch->i_port_id + 8)));
2597
2598         pr_debug("registering session %s\n", ch->sess_name);
2599
2600         nacl = srpt_lookup_acl(sport, ch->i_port_id);
2601         if (!nacl) {
2602                 printk(KERN_INFO "Rejected login because no ACL has been"
2603                        " configured yet for initiator %s.\n", ch->sess_name);
2604                 rej->reason = __constant_cpu_to_be32(
2605                                 SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED);
2606                 goto destroy_ib;
2607         }
2608
2609         ch->sess = transport_init_session();
2610         if (IS_ERR(ch->sess)) {
2611                 rej->reason = __constant_cpu_to_be32(
2612                                 SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
2613                 pr_debug("Failed to create session\n");
2614                 goto deregister_session;
2615         }
2616         ch->sess->se_node_acl = &nacl->nacl;
2617         transport_register_session(&sport->port_tpg_1, &nacl->nacl, ch->sess, ch);
2618
2619         pr_debug("Establish connection sess=%p name=%s cm_id=%p\n", ch->sess,
2620                  ch->sess_name, ch->cm_id);
2621
2622         /* create srp_login_response */
2623         rsp->opcode = SRP_LOGIN_RSP;
2624         rsp->tag = req->tag;
2625         rsp->max_it_iu_len = req->req_it_iu_len;
2626         rsp->max_ti_iu_len = req->req_it_iu_len;
2627         ch->max_ti_iu_len = it_iu_len;
2628         rsp->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT
2629                                               | SRP_BUF_FORMAT_INDIRECT);
2630         rsp->req_lim_delta = cpu_to_be32(ch->rq_size);
2631         atomic_set(&ch->req_lim, ch->rq_size);
2632         atomic_set(&ch->req_lim_delta, 0);
2633
2634         /* create cm reply */
2635         rep_param->qp_num = ch->qp->qp_num;
2636         rep_param->private_data = (void *)rsp;
2637         rep_param->private_data_len = sizeof *rsp;
2638         rep_param->rnr_retry_count = 7;
2639         rep_param->flow_control = 1;
2640         rep_param->failover_accepted = 0;
2641         rep_param->srq = 1;
2642         rep_param->responder_resources = 4;
2643         rep_param->initiator_depth = 4;
2644
2645         ret = ib_send_cm_rep(cm_id, rep_param);
2646         if (ret) {
2647                 printk(KERN_ERR "sending SRP_LOGIN_REQ response failed"
2648                        " (error code = %d)\n", ret);
2649                 goto release_channel;
2650         }
2651
2652         spin_lock_irq(&sdev->spinlock);
2653         list_add_tail(&ch->list, &sdev->rch_list);
2654         spin_unlock_irq(&sdev->spinlock);
2655
2656         goto out;
2657
2658 release_channel:
2659         srpt_set_ch_state(ch, CH_RELEASING);
2660         transport_deregister_session_configfs(ch->sess);
2661
2662 deregister_session:
2663         transport_deregister_session(ch->sess);
2664         ch->sess = NULL;
2665
2666 destroy_ib:
2667         srpt_destroy_ch_ib(ch);
2668
2669 free_ring:
2670         srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
2671                              ch->sport->sdev, ch->rq_size,
2672                              ch->rsp_size, DMA_TO_DEVICE);
2673 free_ch:
2674         kfree(ch);
2675
2676 reject:
2677         rej->opcode = SRP_LOGIN_REJ;
2678         rej->tag = req->tag;
2679         rej->buf_fmt = __constant_cpu_to_be16(SRP_BUF_FORMAT_DIRECT
2680                                               | SRP_BUF_FORMAT_INDIRECT);
2681
2682         ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED, NULL, 0,
2683                              (void *)rej, sizeof *rej);
2684
2685 out:
2686         kfree(rep_param);
2687         kfree(rsp);
2688         kfree(rej);
2689
2690         return ret;
2691 }
2692
2693 static void srpt_cm_rej_recv(struct ib_cm_id *cm_id)
2694 {
2695         printk(KERN_INFO "Received IB REJ for cm_id %p.\n", cm_id);
2696         srpt_drain_channel(cm_id);
2697 }
2698
2699 /**
2700  * srpt_cm_rtu_recv() - Process an IB_CM_RTU_RECEIVED or USER_ESTABLISHED event.
2701  *
2702  * An IB_CM_RTU_RECEIVED message indicates that the connection is established
2703  * and that the recipient may begin transmitting (RTU = ready to use).
2704  */
2705 static void srpt_cm_rtu_recv(struct ib_cm_id *cm_id)
2706 {
2707         struct srpt_rdma_ch *ch;
2708         int ret;
2709
2710         ch = srpt_find_channel(cm_id->context, cm_id);
2711         BUG_ON(!ch);
2712
2713         if (srpt_test_and_set_ch_state(ch, CH_CONNECTING, CH_LIVE)) {
2714                 struct srpt_recv_ioctx *ioctx, *ioctx_tmp;
2715
2716                 ret = srpt_ch_qp_rts(ch, ch->qp);
2717
2718                 list_for_each_entry_safe(ioctx, ioctx_tmp, &ch->cmd_wait_list,
2719                                          wait_list) {
2720                         list_del(&ioctx->wait_list);
2721                         srpt_handle_new_iu(ch, ioctx, NULL);
2722                 }
2723                 if (ret)
2724                         srpt_close_ch(ch);
2725         }
2726 }
2727
2728 static void srpt_cm_timewait_exit(struct ib_cm_id *cm_id)
2729 {
2730         printk(KERN_INFO "Received IB TimeWait exit for cm_id %p.\n", cm_id);
2731         srpt_drain_channel(cm_id);
2732 }
2733
2734 static void srpt_cm_rep_error(struct ib_cm_id *cm_id)
2735 {
2736         printk(KERN_INFO "Received IB REP error for cm_id %p.\n", cm_id);
2737         srpt_drain_channel(cm_id);
2738 }
2739
2740 /**
2741  * srpt_cm_dreq_recv() - Process reception of a DREQ message.
2742  */
2743 static void srpt_cm_dreq_recv(struct ib_cm_id *cm_id)
2744 {
2745         struct srpt_rdma_ch *ch;
2746         unsigned long flags;
2747         bool send_drep = false;
2748
2749         ch = srpt_find_channel(cm_id->context, cm_id);
2750         BUG_ON(!ch);
2751
2752         pr_debug("cm_id= %p ch->state= %d\n", cm_id, srpt_get_ch_state(ch));
2753
2754         spin_lock_irqsave(&ch->spinlock, flags);
2755         switch (ch->state) {
2756         case CH_CONNECTING:
2757         case CH_LIVE:
2758                 send_drep = true;
2759                 ch->state = CH_DISCONNECTING;
2760                 break;
2761         case CH_DISCONNECTING:
2762         case CH_DRAINING:
2763         case CH_RELEASING:
2764                 WARN(true, "unexpected channel state %d\n", ch->state);
2765                 break;
2766         }
2767         spin_unlock_irqrestore(&ch->spinlock, flags);
2768
2769         if (send_drep) {
2770                 if (ib_send_cm_drep(ch->cm_id, NULL, 0) < 0)
2771                         printk(KERN_ERR "Sending IB DREP failed.\n");
2772                 printk(KERN_INFO "Received DREQ and sent DREP for session %s.\n",
2773                        ch->sess_name);
2774         }
2775 }
2776
2777 /**
2778  * srpt_cm_drep_recv() - Process reception of a DREP message.
2779  */
2780 static void srpt_cm_drep_recv(struct ib_cm_id *cm_id)
2781 {
2782         printk(KERN_INFO "Received InfiniBand DREP message for cm_id %p.\n",
2783                cm_id);
2784         srpt_drain_channel(cm_id);
2785 }
2786
2787 /**
2788  * srpt_cm_handler() - IB connection manager callback function.
2789  *
2790  * A non-zero return value will cause the caller destroy the CM ID.
2791  *
2792  * Note: srpt_cm_handler() must only return a non-zero value when transferring
2793  * ownership of the cm_id to a channel by srpt_cm_req_recv() failed. Returning
2794  * a non-zero value in any other case will trigger a race with the
2795  * ib_destroy_cm_id() call in srpt_release_channel().
2796  */
2797 static int srpt_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
2798 {
2799         int ret;
2800
2801         ret = 0;
2802         switch (event->event) {
2803         case IB_CM_REQ_RECEIVED:
2804                 ret = srpt_cm_req_recv(cm_id, &event->param.req_rcvd,
2805                                        event->private_data);
2806                 break;
2807         case IB_CM_REJ_RECEIVED:
2808                 srpt_cm_rej_recv(cm_id);
2809                 break;
2810         case IB_CM_RTU_RECEIVED:
2811         case IB_CM_USER_ESTABLISHED:
2812                 srpt_cm_rtu_recv(cm_id);
2813                 break;
2814         case IB_CM_DREQ_RECEIVED:
2815                 srpt_cm_dreq_recv(cm_id);
2816                 break;
2817         case IB_CM_DREP_RECEIVED:
2818                 srpt_cm_drep_recv(cm_id);
2819                 break;
2820         case IB_CM_TIMEWAIT_EXIT:
2821                 srpt_cm_timewait_exit(cm_id);
2822                 break;
2823         case IB_CM_REP_ERROR:
2824                 srpt_cm_rep_error(cm_id);
2825                 break;
2826         case IB_CM_DREQ_ERROR:
2827                 printk(KERN_INFO "Received IB DREQ ERROR event.\n");
2828                 break;
2829         case IB_CM_MRA_RECEIVED:
2830                 printk(KERN_INFO "Received IB MRA event\n");
2831                 break;
2832         default:
2833                 printk(KERN_ERR "received unrecognized IB CM event %d\n",
2834                        event->event);
2835                 break;
2836         }
2837
2838         return ret;
2839 }
2840
2841 /**
2842  * srpt_perform_rdmas() - Perform IB RDMA.
2843  *
2844  * Returns zero upon success or a negative number upon failure.
2845  */
2846 static int srpt_perform_rdmas(struct srpt_rdma_ch *ch,
2847                               struct srpt_send_ioctx *ioctx)
2848 {
2849         struct ib_send_wr wr;
2850         struct ib_send_wr *bad_wr;
2851         struct rdma_iu *riu;
2852         int i;
2853         int ret;
2854         int sq_wr_avail;
2855         enum dma_data_direction dir;
2856         const int n_rdma = ioctx->n_rdma;
2857
2858         dir = ioctx->cmd.data_direction;
2859         if (dir == DMA_TO_DEVICE) {
2860                 /* write */
2861                 ret = -ENOMEM;
2862                 sq_wr_avail = atomic_sub_return(n_rdma, &ch->sq_wr_avail);
2863                 if (sq_wr_avail < 0) {
2864                         printk(KERN_WARNING "IB send queue full (needed %d)\n",
2865                                n_rdma);
2866                         goto out;
2867                 }
2868         }
2869
2870         ioctx->rdma_aborted = false;
2871         ret = 0;
2872         riu = ioctx->rdma_ius;
2873         memset(&wr, 0, sizeof wr);
2874
2875         for (i = 0; i < n_rdma; ++i, ++riu) {
2876                 if (dir == DMA_FROM_DEVICE) {
2877                         wr.opcode = IB_WR_RDMA_WRITE;
2878                         wr.wr_id = encode_wr_id(i == n_rdma - 1 ?
2879                                                 SRPT_RDMA_WRITE_LAST :
2880                                                 SRPT_RDMA_MID,
2881                                                 ioctx->ioctx.index);
2882                 } else {
2883                         wr.opcode = IB_WR_RDMA_READ;
2884                         wr.wr_id = encode_wr_id(i == n_rdma - 1 ?
2885                                                 SRPT_RDMA_READ_LAST :
2886                                                 SRPT_RDMA_MID,
2887                                                 ioctx->ioctx.index);
2888                 }
2889                 wr.next = NULL;
2890                 wr.wr.rdma.remote_addr = riu->raddr;
2891                 wr.wr.rdma.rkey = riu->rkey;
2892                 wr.num_sge = riu->sge_cnt;
2893                 wr.sg_list = riu->sge;
2894
2895                 /* only get completion event for the last rdma write */
2896                 if (i == (n_rdma - 1) && dir == DMA_TO_DEVICE)
2897                         wr.send_flags = IB_SEND_SIGNALED;
2898
2899                 ret = ib_post_send(ch->qp, &wr, &bad_wr);
2900                 if (ret)
2901                         break;
2902         }
2903
2904         if (ret)
2905                 printk(KERN_ERR "%s[%d]: ib_post_send() returned %d for %d/%d",
2906                                  __func__, __LINE__, ret, i, n_rdma);
2907         if (ret && i > 0) {
2908                 wr.num_sge = 0;
2909                 wr.wr_id = encode_wr_id(SRPT_RDMA_ABORT, ioctx->ioctx.index);
2910                 wr.send_flags = IB_SEND_SIGNALED;
2911                 while (ch->state == CH_LIVE &&
2912                         ib_post_send(ch->qp, &wr, &bad_wr) != 0) {
2913                         printk(KERN_INFO "Trying to abort failed RDMA transfer [%d]",
2914                                 ioctx->ioctx.index);
2915                         msleep(1000);
2916                 }
2917                 while (ch->state != CH_RELEASING && !ioctx->rdma_aborted) {
2918                         printk(KERN_INFO "Waiting until RDMA abort finished [%d]",
2919                                 ioctx->ioctx.index);
2920                         msleep(1000);
2921                 }
2922         }
2923 out:
2924         if (unlikely(dir == DMA_TO_DEVICE && ret < 0))
2925                 atomic_add(n_rdma, &ch->sq_wr_avail);
2926         return ret;
2927 }
2928
2929 /**
2930  * srpt_xfer_data() - Start data transfer from initiator to target.
2931  */
2932 static int srpt_xfer_data(struct srpt_rdma_ch *ch,
2933                           struct srpt_send_ioctx *ioctx)
2934 {
2935         int ret;
2936
2937         ret = srpt_map_sg_to_ib_sge(ch, ioctx);
2938         if (ret) {
2939                 printk(KERN_ERR "%s[%d] ret=%d\n", __func__, __LINE__, ret);
2940                 goto out;
2941         }
2942
2943         ret = srpt_perform_rdmas(ch, ioctx);
2944         if (ret) {
2945                 if (ret == -EAGAIN || ret == -ENOMEM)
2946                         printk(KERN_INFO "%s[%d] queue full -- ret=%d\n",
2947                                    __func__, __LINE__, ret);
2948                 else
2949                         printk(KERN_ERR "%s[%d] fatal error -- ret=%d\n",
2950                                __func__, __LINE__, ret);
2951                 goto out_unmap;
2952         }
2953
2954 out:
2955         return ret;
2956 out_unmap:
2957         srpt_unmap_sg_to_ib_sge(ch, ioctx);
2958         goto out;
2959 }
2960
2961 static int srpt_write_pending_status(struct se_cmd *se_cmd)
2962 {
2963         struct srpt_send_ioctx *ioctx;
2964
2965         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
2966         return srpt_get_cmd_state(ioctx) == SRPT_STATE_NEED_DATA;
2967 }
2968
2969 /*
2970  * srpt_write_pending() - Start data transfer from initiator to target (write).
2971  */
2972 static int srpt_write_pending(struct se_cmd *se_cmd)
2973 {
2974         struct srpt_rdma_ch *ch;
2975         struct srpt_send_ioctx *ioctx;
2976         enum srpt_command_state new_state;
2977         enum rdma_ch_state ch_state;
2978         int ret;
2979
2980         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
2981
2982         new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA);
2983         WARN_ON(new_state == SRPT_STATE_DONE);
2984
2985         ch = ioctx->ch;
2986         BUG_ON(!ch);
2987
2988         ch_state = srpt_get_ch_state(ch);
2989         switch (ch_state) {
2990         case CH_CONNECTING:
2991                 WARN(true, "unexpected channel state %d\n", ch_state);
2992                 ret = -EINVAL;
2993                 goto out;
2994         case CH_LIVE:
2995                 break;
2996         case CH_DISCONNECTING:
2997         case CH_DRAINING:
2998         case CH_RELEASING:
2999                 pr_debug("cmd with tag %lld: channel disconnecting\n",
3000                          ioctx->tag);
3001                 srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN);
3002                 ret = -EINVAL;
3003                 goto out;
3004         }
3005         ret = srpt_xfer_data(ch, ioctx);
3006
3007 out:
3008         return ret;
3009 }
3010
3011 static u8 tcm_to_srp_tsk_mgmt_status(const int tcm_mgmt_status)
3012 {
3013         switch (tcm_mgmt_status) {
3014         case TMR_FUNCTION_COMPLETE:
3015                 return SRP_TSK_MGMT_SUCCESS;
3016         case TMR_FUNCTION_REJECTED:
3017                 return SRP_TSK_MGMT_FUNC_NOT_SUPP;
3018         }
3019         return SRP_TSK_MGMT_FAILED;
3020 }
3021
3022 /**
3023  * srpt_queue_response() - Transmits the response to a SCSI command.
3024  *
3025  * Callback function called by the TCM core. Must not block since it can be
3026  * invoked on the context of the IB completion handler.
3027  */
3028 static int srpt_queue_response(struct se_cmd *cmd)
3029 {
3030         struct srpt_rdma_ch *ch;
3031         struct srpt_send_ioctx *ioctx;
3032         enum srpt_command_state state;
3033         unsigned long flags;
3034         int ret;
3035         enum dma_data_direction dir;
3036         int resp_len;
3037         u8 srp_tm_status;
3038
3039         ret = 0;
3040
3041         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
3042         ch = ioctx->ch;
3043         BUG_ON(!ch);
3044
3045         spin_lock_irqsave(&ioctx->spinlock, flags);
3046         state = ioctx->state;
3047         switch (state) {
3048         case SRPT_STATE_NEW:
3049         case SRPT_STATE_DATA_IN:
3050                 ioctx->state = SRPT_STATE_CMD_RSP_SENT;
3051                 break;
3052         case SRPT_STATE_MGMT:
3053                 ioctx->state = SRPT_STATE_MGMT_RSP_SENT;
3054                 break;
3055         default:
3056                 WARN(true, "ch %p; cmd %d: unexpected command state %d\n",
3057                         ch, ioctx->ioctx.index, ioctx->state);
3058                 break;
3059         }
3060         spin_unlock_irqrestore(&ioctx->spinlock, flags);
3061
3062         if (unlikely(transport_check_aborted_status(&ioctx->cmd, false)
3063                      || WARN_ON_ONCE(state == SRPT_STATE_CMD_RSP_SENT))) {
3064                 atomic_inc(&ch->req_lim_delta);
3065                 srpt_abort_cmd(ioctx);
3066                 goto out;
3067         }
3068
3069         dir = ioctx->cmd.data_direction;
3070
3071         /* For read commands, transfer the data to the initiator. */
3072         if (dir == DMA_FROM_DEVICE && ioctx->cmd.data_length &&
3073             !ioctx->queue_status_only) {
3074                 ret = srpt_xfer_data(ch, ioctx);
3075                 if (ret) {
3076                         printk(KERN_ERR "xfer_data failed for tag %llu\n",
3077                                ioctx->tag);
3078                         goto out;
3079                 }
3080         }
3081
3082         if (state != SRPT_STATE_MGMT)
3083                 resp_len = srpt_build_cmd_rsp(ch, ioctx, ioctx->tag,
3084                                               cmd->scsi_status);
3085         else {
3086                 srp_tm_status
3087                         = tcm_to_srp_tsk_mgmt_status(cmd->se_tmr_req->response);
3088                 resp_len = srpt_build_tskmgmt_rsp(ch, ioctx, srp_tm_status,
3089                                                  ioctx->tag);
3090         }
3091         ret = srpt_post_send(ch, ioctx, resp_len);
3092         if (ret) {
3093                 printk(KERN_ERR "sending cmd response failed for tag %llu\n",
3094                        ioctx->tag);
3095                 srpt_unmap_sg_to_ib_sge(ch, ioctx);
3096                 srpt_set_cmd_state(ioctx, SRPT_STATE_DONE);
3097                 kref_put(&ioctx->kref, srpt_put_send_ioctx_kref);
3098         }
3099
3100 out:
3101         return ret;
3102 }
3103
3104 static int srpt_queue_status(struct se_cmd *cmd)
3105 {
3106         struct srpt_send_ioctx *ioctx;
3107
3108         ioctx = container_of(cmd, struct srpt_send_ioctx, cmd);
3109         BUG_ON(ioctx->sense_data != cmd->sense_buffer);
3110         if (cmd->se_cmd_flags &
3111             (SCF_TRANSPORT_TASK_SENSE | SCF_EMULATED_TASK_SENSE))
3112                 WARN_ON(cmd->scsi_status != SAM_STAT_CHECK_CONDITION);
3113         ioctx->queue_status_only = true;
3114         return srpt_queue_response(cmd);
3115 }
3116
3117 static void srpt_refresh_port_work(struct work_struct *work)
3118 {
3119         struct srpt_port *sport = container_of(work, struct srpt_port, work);
3120
3121         srpt_refresh_port(sport);
3122 }
3123
3124 static int srpt_ch_list_empty(struct srpt_device *sdev)
3125 {
3126         int res;
3127
3128         spin_lock_irq(&sdev->spinlock);
3129         res = list_empty(&sdev->rch_list);
3130         spin_unlock_irq(&sdev->spinlock);
3131
3132         return res;
3133 }
3134
3135 /**
3136  * srpt_release_sdev() - Free the channel resources associated with a target.
3137  */
3138 static int srpt_release_sdev(struct srpt_device *sdev)
3139 {
3140         struct srpt_rdma_ch *ch, *tmp_ch;
3141         int res;
3142
3143         WARN_ON_ONCE(irqs_disabled());
3144
3145         BUG_ON(!sdev);
3146
3147         spin_lock_irq(&sdev->spinlock);
3148         list_for_each_entry_safe(ch, tmp_ch, &sdev->rch_list, list)
3149                 __srpt_close_ch(ch);
3150         spin_unlock_irq(&sdev->spinlock);
3151
3152         res = wait_event_interruptible(sdev->ch_releaseQ,
3153                                        srpt_ch_list_empty(sdev));
3154         if (res)
3155                 printk(KERN_ERR "%s: interrupted.\n", __func__);
3156
3157         return 0;
3158 }
3159
3160 static struct srpt_port *__srpt_lookup_port(const char *name)
3161 {
3162         struct ib_device *dev;
3163         struct srpt_device *sdev;
3164         struct srpt_port *sport;
3165         int i;
3166
3167         list_for_each_entry(sdev, &srpt_dev_list, list) {
3168                 dev = sdev->device;
3169                 if (!dev)
3170                         continue;
3171
3172                 for (i = 0; i < dev->phys_port_cnt; i++) {
3173                         sport = &sdev->port[i];
3174
3175                         if (!strcmp(sport->port_guid, name))
3176                                 return sport;
3177                 }
3178         }
3179
3180         return NULL;
3181 }
3182
3183 static struct srpt_port *srpt_lookup_port(const char *name)
3184 {
3185         struct srpt_port *sport;
3186
3187         spin_lock(&srpt_dev_lock);
3188         sport = __srpt_lookup_port(name);
3189         spin_unlock(&srpt_dev_lock);
3190
3191         return sport;
3192 }
3193
3194 /**
3195  * srpt_add_one() - Infiniband device addition callback function.
3196  */
3197 static void srpt_add_one(struct ib_device *device)
3198 {
3199         struct srpt_device *sdev;
3200         struct srpt_port *sport;
3201         struct ib_srq_init_attr srq_attr;
3202         int i;
3203
3204         pr_debug("device = %p, device->dma_ops = %p\n", device,
3205                  device->dma_ops);
3206
3207         sdev = kzalloc(sizeof *sdev, GFP_KERNEL);
3208         if (!sdev)
3209                 goto err;
3210
3211         sdev->device = device;
3212         INIT_LIST_HEAD(&sdev->rch_list);
3213         init_waitqueue_head(&sdev->ch_releaseQ);
3214         spin_lock_init(&sdev->spinlock);
3215
3216         if (ib_query_device(device, &sdev->dev_attr))
3217                 goto free_dev;
3218
3219         sdev->pd = ib_alloc_pd(device);
3220         if (IS_ERR(sdev->pd))
3221                 goto free_dev;
3222
3223         sdev->mr = ib_get_dma_mr(sdev->pd, IB_ACCESS_LOCAL_WRITE);
3224         if (IS_ERR(sdev->mr))
3225                 goto err_pd;
3226
3227         sdev->srq_size = min(srpt_srq_size, sdev->dev_attr.max_srq_wr);
3228
3229         srq_attr.event_handler = srpt_srq_event;
3230         srq_attr.srq_context = (void *)sdev;
3231         srq_attr.attr.max_wr = sdev->srq_size;
3232         srq_attr.attr.max_sge = 1;
3233         srq_attr.attr.srq_limit = 0;
3234         srq_attr.srq_type = IB_SRQT_BASIC;
3235
3236         sdev->srq = ib_create_srq(sdev->pd, &srq_attr);
3237         if (IS_ERR(sdev->srq))
3238                 goto err_mr;
3239
3240         pr_debug("%s: create SRQ #wr= %d max_allow=%d dev= %s\n",
3241                  __func__, sdev->srq_size, sdev->dev_attr.max_srq_wr,
3242                  device->name);
3243
3244         if (!srpt_service_guid)
3245                 srpt_service_guid = be64_to_cpu(device->node_guid);
3246
3247         sdev->cm_id = ib_create_cm_id(device, srpt_cm_handler, sdev);
3248         if (IS_ERR(sdev->cm_id))
3249                 goto err_srq;
3250
3251         /* print out target login information */
3252         pr_debug("Target login info: id_ext=%016llx,ioc_guid=%016llx,"
3253                  "pkey=ffff,service_id=%016llx\n", srpt_service_guid,
3254                  srpt_service_guid, srpt_service_guid);
3255
3256         /*
3257          * We do not have a consistent service_id (ie. also id_ext of target_id)
3258          * to identify this target. We currently use the guid of the first HCA
3259          * in the system as service_id; therefore, the target_id will change
3260          * if this HCA is gone bad and replaced by different HCA
3261          */
3262         if (ib_cm_listen(sdev->cm_id, cpu_to_be64(srpt_service_guid), 0, NULL))
3263                 goto err_cm;
3264
3265         INIT_IB_EVENT_HANDLER(&sdev->event_handler, sdev->device,
3266                               srpt_event_handler);
3267         if (ib_register_event_handler(&sdev->event_handler))
3268                 goto err_cm;
3269
3270         sdev->ioctx_ring = (struct srpt_recv_ioctx **)
3271                 srpt_alloc_ioctx_ring(sdev, sdev->srq_size,
3272                                       sizeof(*sdev->ioctx_ring[0]),
3273                                       srp_max_req_size, DMA_FROM_DEVICE);
3274         if (!sdev->ioctx_ring)
3275                 goto err_event;
3276
3277         for (i = 0; i < sdev->srq_size; ++i)
3278                 srpt_post_recv(sdev, sdev->ioctx_ring[i]);
3279
3280         WARN_ON(sdev->device->phys_port_cnt > ARRAY_SIZE(sdev->port));
3281
3282         for (i = 1; i <= sdev->device->phys_port_cnt; i++) {
3283                 sport = &sdev->port[i - 1];
3284                 sport->sdev = sdev;
3285                 sport->port = i;
3286                 sport->port_attrib.srp_max_rdma_size = DEFAULT_MAX_RDMA_SIZE;
3287                 sport->port_attrib.srp_max_rsp_size = DEFAULT_MAX_RSP_SIZE;
3288                 sport->port_attrib.srp_sq_size = DEF_SRPT_SQ_SIZE;
3289                 INIT_WORK(&sport->work, srpt_refresh_port_work);
3290                 INIT_LIST_HEAD(&sport->port_acl_list);
3291                 spin_lock_init(&sport->port_acl_lock);
3292
3293                 if (srpt_refresh_port(sport)) {
3294                         printk(KERN_ERR "MAD registration failed for %s-%d.\n",
3295                                srpt_sdev_name(sdev), i);
3296                         goto err_ring;
3297                 }
3298                 snprintf(sport->port_guid, sizeof(sport->port_guid),
3299                         "0x%016llx%016llx",
3300                         be64_to_cpu(sport->gid.global.subnet_prefix),
3301                         be64_to_cpu(sport->gid.global.interface_id));
3302         }
3303
3304         spin_lock(&srpt_dev_lock);
3305         list_add_tail(&sdev->list, &srpt_dev_list);
3306         spin_unlock(&srpt_dev_lock);
3307
3308 out:
3309         ib_set_client_data(device, &srpt_client, sdev);
3310         pr_debug("added %s.\n", device->name);
3311         return;
3312
3313 err_ring:
3314         srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
3315                              sdev->srq_size, srp_max_req_size,
3316                              DMA_FROM_DEVICE);
3317 err_event:
3318         ib_unregister_event_handler(&sdev->event_handler);
3319 err_cm:
3320         ib_destroy_cm_id(sdev->cm_id);
3321 err_srq:
3322         ib_destroy_srq(sdev->srq);
3323 err_mr:
3324         ib_dereg_mr(sdev->mr);
3325 err_pd:
3326         ib_dealloc_pd(sdev->pd);
3327 free_dev:
3328         kfree(sdev);
3329 err:
3330         sdev = NULL;
3331         printk(KERN_INFO "%s(%s) failed.\n", __func__, device->name);
3332         goto out;
3333 }
3334
3335 /**
3336  * srpt_remove_one() - InfiniBand device removal callback function.
3337  */
3338 static void srpt_remove_one(struct ib_device *device)
3339 {
3340         struct srpt_device *sdev;
3341         int i;
3342
3343         sdev = ib_get_client_data(device, &srpt_client);
3344         if (!sdev) {
3345                 printk(KERN_INFO "%s(%s): nothing to do.\n", __func__,
3346                        device->name);
3347                 return;
3348         }
3349
3350         srpt_unregister_mad_agent(sdev);
3351
3352         ib_unregister_event_handler(&sdev->event_handler);
3353
3354         /* Cancel any work queued by the just unregistered IB event handler. */
3355         for (i = 0; i < sdev->device->phys_port_cnt; i++)
3356                 cancel_work_sync(&sdev->port[i].work);
3357
3358         ib_destroy_cm_id(sdev->cm_id);
3359
3360         /*
3361          * Unregistering a target must happen after destroying sdev->cm_id
3362          * such that no new SRP_LOGIN_REQ information units can arrive while
3363          * destroying the target.
3364          */
3365         spin_lock(&srpt_dev_lock);
3366         list_del(&sdev->list);
3367         spin_unlock(&srpt_dev_lock);
3368         srpt_release_sdev(sdev);
3369
3370         ib_destroy_srq(sdev->srq);
3371         ib_dereg_mr(sdev->mr);
3372         ib_dealloc_pd(sdev->pd);
3373
3374         srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
3375                              sdev->srq_size, srp_max_req_size, DMA_FROM_DEVICE);
3376         sdev->ioctx_ring = NULL;
3377         kfree(sdev);
3378 }
3379
3380 static struct ib_client srpt_client = {
3381         .name = DRV_NAME,
3382         .add = srpt_add_one,
3383         .remove = srpt_remove_one
3384 };
3385
3386 static int srpt_check_true(struct se_portal_group *se_tpg)
3387 {
3388         return 1;
3389 }
3390
3391 static int srpt_check_false(struct se_portal_group *se_tpg)
3392 {
3393         return 0;
3394 }
3395
3396 static char *srpt_get_fabric_name(void)
3397 {
3398         return "srpt";
3399 }
3400
3401 static u8 srpt_get_fabric_proto_ident(struct se_portal_group *se_tpg)
3402 {
3403         return SCSI_TRANSPORTID_PROTOCOLID_SRP;
3404 }
3405
3406 static char *srpt_get_fabric_wwn(struct se_portal_group *tpg)
3407 {
3408         struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1);
3409
3410         return sport->port_guid;
3411 }
3412
3413 static u16 srpt_get_tag(struct se_portal_group *tpg)
3414 {
3415         return 1;
3416 }
3417
3418 static u32 srpt_get_default_depth(struct se_portal_group *se_tpg)
3419 {
3420         return 1;
3421 }
3422
3423 static u32 srpt_get_pr_transport_id(struct se_portal_group *se_tpg,
3424                                     struct se_node_acl *se_nacl,
3425                                     struct t10_pr_registration *pr_reg,
3426                                     int *format_code, unsigned char *buf)
3427 {
3428         struct srpt_node_acl *nacl;
3429         struct spc_rdma_transport_id *tr_id;
3430
3431         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3432         tr_id = (void *)buf;
3433         tr_id->protocol_identifier = SCSI_TRANSPORTID_PROTOCOLID_SRP;
3434         memcpy(tr_id->i_port_id, nacl->i_port_id, sizeof(tr_id->i_port_id));
3435         return sizeof(*tr_id);
3436 }
3437
3438 static u32 srpt_get_pr_transport_id_len(struct se_portal_group *se_tpg,
3439                                         struct se_node_acl *se_nacl,
3440                                         struct t10_pr_registration *pr_reg,
3441                                         int *format_code)
3442 {
3443         *format_code = 0;
3444         return sizeof(struct spc_rdma_transport_id);
3445 }
3446
3447 static char *srpt_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
3448                                             const char *buf, u32 *out_tid_len,
3449                                             char **port_nexus_ptr)
3450 {
3451         struct spc_rdma_transport_id *tr_id;
3452
3453         *port_nexus_ptr = NULL;
3454         *out_tid_len = sizeof(struct spc_rdma_transport_id);
3455         tr_id = (void *)buf;
3456         return (char *)tr_id->i_port_id;
3457 }
3458
3459 static struct se_node_acl *srpt_alloc_fabric_acl(struct se_portal_group *se_tpg)
3460 {
3461         struct srpt_node_acl *nacl;
3462
3463         nacl = kzalloc(sizeof(struct srpt_node_acl), GFP_KERNEL);
3464         if (!nacl) {
3465                 printk(KERN_ERR "Unable to allocate struct srpt_node_acl\n");
3466                 return NULL;
3467         }
3468
3469         return &nacl->nacl;
3470 }
3471
3472 static void srpt_release_fabric_acl(struct se_portal_group *se_tpg,
3473                                     struct se_node_acl *se_nacl)
3474 {
3475         struct srpt_node_acl *nacl;
3476
3477         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3478         kfree(nacl);
3479 }
3480
3481 static u32 srpt_tpg_get_inst_index(struct se_portal_group *se_tpg)
3482 {
3483         return 1;
3484 }
3485
3486 static void srpt_release_cmd(struct se_cmd *se_cmd)
3487 {
3488 }
3489
3490 /**
3491  * srpt_shutdown_session() - Whether or not a session may be shut down.
3492  */
3493 static int srpt_shutdown_session(struct se_session *se_sess)
3494 {
3495         return true;
3496 }
3497
3498 /**
3499  * srpt_close_session() - Forcibly close a session.
3500  *
3501  * Callback function invoked by the TCM core to clean up sessions associated
3502  * with a node ACL when the user invokes
3503  * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3504  */
3505 static void srpt_close_session(struct se_session *se_sess)
3506 {
3507         DECLARE_COMPLETION_ONSTACK(release_done);
3508         struct srpt_rdma_ch *ch;
3509         struct srpt_device *sdev;
3510         int res;
3511
3512         ch = se_sess->fabric_sess_ptr;
3513         WARN_ON(ch->sess != se_sess);
3514
3515         pr_debug("ch %p state %d\n", ch, srpt_get_ch_state(ch));
3516
3517         sdev = ch->sport->sdev;
3518         spin_lock_irq(&sdev->spinlock);
3519         BUG_ON(ch->release_done);
3520         ch->release_done = &release_done;
3521         __srpt_close_ch(ch);
3522         spin_unlock_irq(&sdev->spinlock);
3523
3524         res = wait_for_completion_timeout(&release_done, 60 * HZ);
3525         WARN_ON(res <= 0);
3526 }
3527
3528 /**
3529  * srpt_sess_get_index() - Return the value of scsiAttIntrPortIndex (SCSI-MIB).
3530  *
3531  * A quote from RFC 4455 (SCSI-MIB) about this MIB object:
3532  * This object represents an arbitrary integer used to uniquely identify a
3533  * particular attached remote initiator port to a particular SCSI target port
3534  * within a particular SCSI target device within a particular SCSI instance.
3535  */
3536 static u32 srpt_sess_get_index(struct se_session *se_sess)
3537 {
3538         return 0;
3539 }
3540
3541 static void srpt_set_default_node_attrs(struct se_node_acl *nacl)
3542 {
3543 }
3544
3545 static u32 srpt_get_task_tag(struct se_cmd *se_cmd)
3546 {
3547         struct srpt_send_ioctx *ioctx;
3548
3549         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
3550         return ioctx->tag;
3551 }
3552
3553 /* Note: only used from inside debug printk's by the TCM core. */
3554 static int srpt_get_tcm_cmd_state(struct se_cmd *se_cmd)
3555 {
3556         struct srpt_send_ioctx *ioctx;
3557
3558         ioctx = container_of(se_cmd, struct srpt_send_ioctx, cmd);
3559         return srpt_get_cmd_state(ioctx);
3560 }
3561
3562 static u16 srpt_set_fabric_sense_len(struct se_cmd *cmd, u32 sense_length)
3563 {
3564         return 0;
3565 }
3566
3567 static u16 srpt_get_fabric_sense_len(void)
3568 {
3569         return 0;
3570 }
3571
3572 /**
3573  * srpt_parse_i_port_id() - Parse an initiator port ID.
3574  * @name: ASCII representation of a 128-bit initiator port ID.
3575  * @i_port_id: Binary 128-bit port ID.
3576  */
3577 static int srpt_parse_i_port_id(u8 i_port_id[16], const char *name)
3578 {
3579         const char *p;
3580         unsigned len, count, leading_zero_bytes;
3581         int ret, rc;
3582
3583         p = name;
3584         if (strnicmp(p, "0x", 2) == 0)
3585                 p += 2;
3586         ret = -EINVAL;
3587         len = strlen(p);
3588         if (len % 2)
3589                 goto out;
3590         count = min(len / 2, 16U);
3591         leading_zero_bytes = 16 - count;
3592         memset(i_port_id, 0, leading_zero_bytes);
3593         rc = hex2bin(i_port_id + leading_zero_bytes, p, count);
3594         if (rc < 0)
3595                 pr_debug("hex2bin failed for srpt_parse_i_port_id: %d\n", rc);
3596         ret = 0;
3597 out:
3598         return ret;
3599 }
3600
3601 /*
3602  * configfs callback function invoked for
3603  * mkdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3604  */
3605 static struct se_node_acl *srpt_make_nodeacl(struct se_portal_group *tpg,
3606                                              struct config_group *group,
3607                                              const char *name)
3608 {
3609         struct srpt_port *sport = container_of(tpg, struct srpt_port, port_tpg_1);
3610         struct se_node_acl *se_nacl, *se_nacl_new;
3611         struct srpt_node_acl *nacl;
3612         int ret = 0;
3613         u32 nexus_depth = 1;
3614         u8 i_port_id[16];
3615
3616         if (srpt_parse_i_port_id(i_port_id, name) < 0) {
3617                 printk(KERN_ERR "invalid initiator port ID %s\n", name);
3618                 ret = -EINVAL;
3619                 goto err;
3620         }
3621
3622         se_nacl_new = srpt_alloc_fabric_acl(tpg);
3623         if (!se_nacl_new) {
3624                 ret = -ENOMEM;
3625                 goto err;
3626         }
3627         /*
3628          * nacl_new may be released by core_tpg_add_initiator_node_acl()
3629          * when converting a node ACL from demo mode to explict
3630          */
3631         se_nacl = core_tpg_add_initiator_node_acl(tpg, se_nacl_new, name,
3632                                                   nexus_depth);
3633         if (IS_ERR(se_nacl)) {
3634                 ret = PTR_ERR(se_nacl);
3635                 goto err;
3636         }
3637         /* Locate our struct srpt_node_acl and set sdev and i_port_id. */
3638         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3639         memcpy(&nacl->i_port_id[0], &i_port_id[0], 16);
3640         nacl->sport = sport;
3641
3642         spin_lock_irq(&sport->port_acl_lock);
3643         list_add_tail(&nacl->list, &sport->port_acl_list);
3644         spin_unlock_irq(&sport->port_acl_lock);
3645
3646         return se_nacl;
3647 err:
3648         return ERR_PTR(ret);
3649 }
3650
3651 /*
3652  * configfs callback function invoked for
3653  * rmdir /sys/kernel/config/target/$driver/$port/$tpg/acls/$i_port_id
3654  */
3655 static void srpt_drop_nodeacl(struct se_node_acl *se_nacl)
3656 {
3657         struct srpt_node_acl *nacl;
3658         struct srpt_device *sdev;
3659         struct srpt_port *sport;
3660
3661         nacl = container_of(se_nacl, struct srpt_node_acl, nacl);
3662         sport = nacl->sport;
3663         sdev = sport->sdev;
3664         spin_lock_irq(&sport->port_acl_lock);
3665         list_del(&nacl->list);
3666         spin_unlock_irq(&sport->port_acl_lock);
3667         core_tpg_del_initiator_node_acl(&sport->port_tpg_1, se_nacl, 1);
3668         srpt_release_fabric_acl(NULL, se_nacl);
3669 }
3670
3671 static ssize_t srpt_tpg_attrib_show_srp_max_rdma_size(
3672         struct se_portal_group *se_tpg,
3673         char *page)
3674 {
3675         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3676
3677         return sprintf(page, "%u\n", sport->port_attrib.srp_max_rdma_size);
3678 }
3679
3680 static ssize_t srpt_tpg_attrib_store_srp_max_rdma_size(
3681         struct se_portal_group *se_tpg,
3682         const char *page,
3683         size_t count)
3684 {
3685         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3686         unsigned long val;
3687         int ret;
3688
3689         ret = strict_strtoul(page, 0, &val);
3690         if (ret < 0) {
3691                 pr_err("strict_strtoul() failed with ret: %d\n", ret);
3692                 return -EINVAL;
3693         }
3694         if (val > MAX_SRPT_RDMA_SIZE) {
3695                 pr_err("val: %lu exceeds MAX_SRPT_RDMA_SIZE: %d\n", val,
3696                         MAX_SRPT_RDMA_SIZE);
3697                 return -EINVAL;
3698         }
3699         if (val < DEFAULT_MAX_RDMA_SIZE) {
3700                 pr_err("val: %lu smaller than DEFAULT_MAX_RDMA_SIZE: %d\n",
3701                         val, DEFAULT_MAX_RDMA_SIZE);
3702                 return -EINVAL;
3703         }
3704         sport->port_attrib.srp_max_rdma_size = val;
3705
3706         return count;
3707 }
3708
3709 TF_TPG_ATTRIB_ATTR(srpt, srp_max_rdma_size, S_IRUGO | S_IWUSR);
3710
3711 static ssize_t srpt_tpg_attrib_show_srp_max_rsp_size(
3712         struct se_portal_group *se_tpg,
3713         char *page)
3714 {
3715         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3716
3717         return sprintf(page, "%u\n", sport->port_attrib.srp_max_rsp_size);
3718 }
3719
3720 static ssize_t srpt_tpg_attrib_store_srp_max_rsp_size(
3721         struct se_portal_group *se_tpg,
3722         const char *page,
3723         size_t count)
3724 {
3725         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3726         unsigned long val;
3727         int ret;
3728
3729         ret = strict_strtoul(page, 0, &val);
3730         if (ret < 0) {
3731                 pr_err("strict_strtoul() failed with ret: %d\n", ret);
3732                 return -EINVAL;
3733         }
3734         if (val > MAX_SRPT_RSP_SIZE) {
3735                 pr_err("val: %lu exceeds MAX_SRPT_RSP_SIZE: %d\n", val,
3736                         MAX_SRPT_RSP_SIZE);
3737                 return -EINVAL;
3738         }
3739         if (val < MIN_MAX_RSP_SIZE) {
3740                 pr_err("val: %lu smaller than MIN_MAX_RSP_SIZE: %d\n", val,
3741                         MIN_MAX_RSP_SIZE);
3742                 return -EINVAL;
3743         }
3744         sport->port_attrib.srp_max_rsp_size = val;
3745
3746         return count;
3747 }
3748
3749 TF_TPG_ATTRIB_ATTR(srpt, srp_max_rsp_size, S_IRUGO | S_IWUSR);
3750
3751 static ssize_t srpt_tpg_attrib_show_srp_sq_size(
3752         struct se_portal_group *se_tpg,
3753         char *page)
3754 {
3755         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3756
3757         return sprintf(page, "%u\n", sport->port_attrib.srp_sq_size);
3758 }
3759
3760 static ssize_t srpt_tpg_attrib_store_srp_sq_size(
3761         struct se_portal_group *se_tpg,
3762         const char *page,
3763         size_t count)
3764 {
3765         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3766         unsigned long val;
3767         int ret;
3768
3769         ret = strict_strtoul(page, 0, &val);
3770         if (ret < 0) {
3771                 pr_err("strict_strtoul() failed with ret: %d\n", ret);
3772                 return -EINVAL;
3773         }
3774         if (val > MAX_SRPT_SRQ_SIZE) {
3775                 pr_err("val: %lu exceeds MAX_SRPT_SRQ_SIZE: %d\n", val,
3776                         MAX_SRPT_SRQ_SIZE);
3777                 return -EINVAL;
3778         }
3779         if (val < MIN_SRPT_SRQ_SIZE) {
3780                 pr_err("val: %lu smaller than MIN_SRPT_SRQ_SIZE: %d\n", val,
3781                         MIN_SRPT_SRQ_SIZE);
3782                 return -EINVAL;
3783         }
3784         sport->port_attrib.srp_sq_size = val;
3785
3786         return count;
3787 }
3788
3789 TF_TPG_ATTRIB_ATTR(srpt, srp_sq_size, S_IRUGO | S_IWUSR);
3790
3791 static struct configfs_attribute *srpt_tpg_attrib_attrs[] = {
3792         &srpt_tpg_attrib_srp_max_rdma_size.attr,
3793         &srpt_tpg_attrib_srp_max_rsp_size.attr,
3794         &srpt_tpg_attrib_srp_sq_size.attr,
3795         NULL,
3796 };
3797
3798 static ssize_t srpt_tpg_show_enable(
3799         struct se_portal_group *se_tpg,
3800         char *page)
3801 {
3802         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3803
3804         return snprintf(page, PAGE_SIZE, "%d\n", (sport->enabled) ? 1: 0);
3805 }
3806
3807 static ssize_t srpt_tpg_store_enable(
3808         struct se_portal_group *se_tpg,
3809         const char *page,
3810         size_t count)
3811 {
3812         struct srpt_port *sport = container_of(se_tpg, struct srpt_port, port_tpg_1);
3813         unsigned long tmp;
3814         int ret;
3815
3816         ret = strict_strtoul(page, 0, &tmp);
3817         if (ret < 0) {
3818                 printk(KERN_ERR "Unable to extract srpt_tpg_store_enable\n");
3819                 return -EINVAL;
3820         }
3821
3822         if ((tmp != 0) && (tmp != 1)) {
3823                 printk(KERN_ERR "Illegal value for srpt_tpg_store_enable: %lu\n", tmp);
3824                 return -EINVAL;
3825         }
3826         if (tmp == 1)
3827                 sport->enabled = true;
3828         else
3829                 sport->enabled = false;
3830
3831         return count;
3832 }
3833
3834 TF_TPG_BASE_ATTR(srpt, enable, S_IRUGO | S_IWUSR);
3835
3836 static struct configfs_attribute *srpt_tpg_attrs[] = {
3837         &srpt_tpg_enable.attr,
3838         NULL,
3839 };
3840
3841 /**
3842  * configfs callback invoked for
3843  * mkdir /sys/kernel/config/target/$driver/$port/$tpg
3844  */
3845 static struct se_portal_group *srpt_make_tpg(struct se_wwn *wwn,
3846                                              struct config_group *group,
3847                                              const char *name)
3848 {
3849         struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn);
3850         int res;
3851
3852         /* Initialize sport->port_wwn and sport->port_tpg_1 */
3853         res = core_tpg_register(&srpt_target->tf_ops, &sport->port_wwn,
3854                         &sport->port_tpg_1, sport, TRANSPORT_TPG_TYPE_NORMAL);
3855         if (res)
3856                 return ERR_PTR(res);
3857
3858         return &sport->port_tpg_1;
3859 }
3860
3861 /**
3862  * configfs callback invoked for
3863  * rmdir /sys/kernel/config/target/$driver/$port/$tpg
3864  */
3865 static void srpt_drop_tpg(struct se_portal_group *tpg)
3866 {
3867         struct srpt_port *sport = container_of(tpg,
3868                                 struct srpt_port, port_tpg_1);
3869
3870         sport->enabled = false;
3871         core_tpg_deregister(&sport->port_tpg_1);
3872 }
3873
3874 /**
3875  * configfs callback invoked for
3876  * mkdir /sys/kernel/config/target/$driver/$port
3877  */
3878 static struct se_wwn *srpt_make_tport(struct target_fabric_configfs *tf,
3879                                       struct config_group *group,
3880                                       const char *name)
3881 {
3882         struct srpt_port *sport;
3883         int ret;
3884
3885         sport = srpt_lookup_port(name);
3886         pr_debug("make_tport(%s)\n", name);
3887         ret = -EINVAL;
3888         if (!sport)
3889                 goto err;
3890
3891         return &sport->port_wwn;
3892
3893 err:
3894         return ERR_PTR(ret);
3895 }
3896
3897 /**
3898  * configfs callback invoked for
3899  * rmdir /sys/kernel/config/target/$driver/$port
3900  */
3901 static void srpt_drop_tport(struct se_wwn *wwn)
3902 {
3903         struct srpt_port *sport = container_of(wwn, struct srpt_port, port_wwn);
3904
3905         pr_debug("drop_tport(%s\n", config_item_name(&sport->port_wwn.wwn_group.cg_item));
3906 }
3907
3908 static ssize_t srpt_wwn_show_attr_version(struct target_fabric_configfs *tf,
3909                                               char *buf)
3910 {
3911         return scnprintf(buf, PAGE_SIZE, "%s\n", DRV_VERSION);
3912 }
3913
3914 TF_WWN_ATTR_RO(srpt, version);
3915
3916 static struct configfs_attribute *srpt_wwn_attrs[] = {
3917         &srpt_wwn_version.attr,
3918         NULL,
3919 };
3920
3921 static struct target_core_fabric_ops srpt_template = {
3922         .get_fabric_name                = srpt_get_fabric_name,
3923         .get_fabric_proto_ident         = srpt_get_fabric_proto_ident,
3924         .tpg_get_wwn                    = srpt_get_fabric_wwn,
3925         .tpg_get_tag                    = srpt_get_tag,
3926         .tpg_get_default_depth          = srpt_get_default_depth,
3927         .tpg_get_pr_transport_id        = srpt_get_pr_transport_id,
3928         .tpg_get_pr_transport_id_len    = srpt_get_pr_transport_id_len,
3929         .tpg_parse_pr_out_transport_id  = srpt_parse_pr_out_transport_id,
3930         .tpg_check_demo_mode            = srpt_check_false,
3931         .tpg_check_demo_mode_cache      = srpt_check_true,
3932         .tpg_check_demo_mode_write_protect = srpt_check_true,
3933         .tpg_check_prod_mode_write_protect = srpt_check_false,
3934         .tpg_alloc_fabric_acl           = srpt_alloc_fabric_acl,
3935         .tpg_release_fabric_acl         = srpt_release_fabric_acl,
3936         .tpg_get_inst_index             = srpt_tpg_get_inst_index,
3937         .release_cmd                    = srpt_release_cmd,
3938         .check_stop_free                = srpt_check_stop_free,
3939         .shutdown_session               = srpt_shutdown_session,
3940         .close_session                  = srpt_close_session,
3941         .sess_get_index                 = srpt_sess_get_index,
3942         .sess_get_initiator_sid         = NULL,
3943         .write_pending                  = srpt_write_pending,
3944         .write_pending_status           = srpt_write_pending_status,
3945         .set_default_node_attributes    = srpt_set_default_node_attrs,
3946         .get_task_tag                   = srpt_get_task_tag,
3947         .get_cmd_state                  = srpt_get_tcm_cmd_state,
3948         .queue_data_in                  = srpt_queue_response,
3949         .queue_status                   = srpt_queue_status,
3950         .queue_tm_rsp                   = srpt_queue_response,
3951         .get_fabric_sense_len           = srpt_get_fabric_sense_len,
3952         .set_fabric_sense_len           = srpt_set_fabric_sense_len,
3953         /*
3954          * Setup function pointers for generic logic in
3955          * target_core_fabric_configfs.c
3956          */
3957         .fabric_make_wwn                = srpt_make_tport,
3958         .fabric_drop_wwn                = srpt_drop_tport,
3959         .fabric_make_tpg                = srpt_make_tpg,
3960         .fabric_drop_tpg                = srpt_drop_tpg,
3961         .fabric_post_link               = NULL,
3962         .fabric_pre_unlink              = NULL,
3963         .fabric_make_np                 = NULL,
3964         .fabric_drop_np                 = NULL,
3965         .fabric_make_nodeacl            = srpt_make_nodeacl,
3966         .fabric_drop_nodeacl            = srpt_drop_nodeacl,
3967 };
3968
3969 /**
3970  * srpt_init_module() - Kernel module initialization.
3971  *
3972  * Note: Since ib_register_client() registers callback functions, and since at
3973  * least one of these callback functions (srpt_add_one()) calls target core
3974  * functions, this driver must be registered with the target core before
3975  * ib_register_client() is called.
3976  */
3977 static int __init srpt_init_module(void)
3978 {
3979         int ret;
3980
3981         ret = -EINVAL;
3982         if (srp_max_req_size < MIN_MAX_REQ_SIZE) {
3983                 printk(KERN_ERR "invalid value %d for kernel module parameter"
3984                        " srp_max_req_size -- must be at least %d.\n",
3985                        srp_max_req_size, MIN_MAX_REQ_SIZE);
3986                 goto out;
3987         }
3988
3989         if (srpt_srq_size < MIN_SRPT_SRQ_SIZE
3990             || srpt_srq_size > MAX_SRPT_SRQ_SIZE) {
3991                 printk(KERN_ERR "invalid value %d for kernel module parameter"
3992                        " srpt_srq_size -- must be in the range [%d..%d].\n",
3993                        srpt_srq_size, MIN_SRPT_SRQ_SIZE, MAX_SRPT_SRQ_SIZE);
3994                 goto out;
3995         }
3996
3997         srpt_target = target_fabric_configfs_init(THIS_MODULE, "srpt");
3998         if (IS_ERR(srpt_target)) {
3999                 printk(KERN_ERR "couldn't register\n");
4000                 ret = PTR_ERR(srpt_target);
4001                 goto out;
4002         }
4003
4004         srpt_target->tf_ops = srpt_template;
4005
4006         /*
4007          * Set up default attribute lists.
4008          */
4009         srpt_target->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = srpt_wwn_attrs;
4010         srpt_target->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = srpt_tpg_attrs;
4011         srpt_target->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = srpt_tpg_attrib_attrs;
4012         srpt_target->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
4013         srpt_target->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
4014         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;
4015         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
4016         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
4017         srpt_target->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;
4018
4019         ret = target_fabric_configfs_register(srpt_target);
4020         if (ret < 0) {
4021                 printk(KERN_ERR "couldn't register\n");
4022                 goto out_free_target;
4023         }
4024
4025         ret = ib_register_client(&srpt_client);
4026         if (ret) {
4027                 printk(KERN_ERR "couldn't register IB client\n");
4028                 goto out_unregister_target;
4029         }
4030
4031         return 0;
4032
4033 out_unregister_target:
4034         target_fabric_configfs_deregister(srpt_target);
4035         srpt_target = NULL;
4036 out_free_target:
4037         if (srpt_target)
4038                 target_fabric_configfs_free(srpt_target);
4039 out:
4040         return ret;
4041 }
4042
4043 static void __exit srpt_cleanup_module(void)
4044 {
4045         ib_unregister_client(&srpt_client);
4046         target_fabric_configfs_deregister(srpt_target);
4047         srpt_target = NULL;
4048 }
4049
4050 module_init(srpt_init_module);
4051 module_exit(srpt_cleanup_module);