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