drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c

   1 /*******************************************************************************
   2  * IBM Virtual SCSI Target Driver
   3  * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
   4  *                         Santiago Leon (santil@us.ibm.com) IBM Corp.
   5  *                         Linda Xie (lxie@us.ibm.com) IBM Corp.
   6  *
   7  * Copyright (C) 2005-2011 FUJITA Tomonori <tomof@acm.org>
   8  * Copyright (C) 2010 Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * Authors: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
  11  * Authors: Michael Cyr <mikecyr@linux.vnet.ibm.com>
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  ****************************************************************************/
  24
  25 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  26
  27 #include <linux/module.h>
  28 #include <linux/kernel.h>
  29 #include <linux/slab.h>
  30 #include <linux/types.h>
  31 #include <linux/list.h>
  32 #include <linux/string.h>
  33 #include <linux/delay.h>
  34
  35 #include <target/target_core_base.h>
  36 #include <target/target_core_fabric.h>
  37
  38 #include <asm/hvcall.h>
  39 #include <asm/vio.h>
  40
  41 #include <scsi/viosrp.h>
  42
  43 #include "ibmvscsi_tgt.h"
  44
  45 #define IBMVSCSIS_VERSION       "v0.2"
  46
  47 #define INITIAL_SRP_LIMIT       800
  48 #define DEFAULT_MAX_SECTORS     256
  49 #define MAX_TXU                 1024 * 1024
  50
  51 static uint max_vdma_size = MAX_H_COPY_RDMA;
  52
  53 static char system_id[SYS_ID_NAME_LEN] = "";
  54 static char partition_name[PARTITION_NAMELEN] = "UNKNOWN";
  55 static uint partition_number = -1;
  56
  57 /* Adapter list and lock to control it */
  58 static DEFINE_SPINLOCK(ibmvscsis_dev_lock);
  59 static LIST_HEAD(ibmvscsis_dev_list);
  60
  61 static long ibmvscsis_parse_command(struct scsi_info *vscsi,
  62                                     struct viosrp_crq *crq);
  63
  64 static void ibmvscsis_adapter_idle(struct scsi_info *vscsi);
  65
  66 static void ibmvscsis_determine_resid(struct se_cmd *se_cmd,
  67                                       struct srp_rsp *rsp)
  68 {
  69         u32 residual_count = se_cmd->residual_count;
  70
  71         if (!residual_count)
  72                 return;
  73
  74         if (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
  75                 if (se_cmd->data_direction == DMA_TO_DEVICE) {
  76                         /* residual data from an underflow write */
  77                         rsp->flags = SRP_RSP_FLAG_DOUNDER;
  78                         rsp->data_out_res_cnt = cpu_to_be32(residual_count);
  79                 } else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
  80                         /* residual data from an underflow read */
  81                         rsp->flags = SRP_RSP_FLAG_DIUNDER;
  82                         rsp->data_in_res_cnt = cpu_to_be32(residual_count);
  83                 }
  84         } else if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
  85                 if (se_cmd->data_direction == DMA_TO_DEVICE) {
  86                         /* residual data from an overflow write */
  87                         rsp->flags = SRP_RSP_FLAG_DOOVER;
  88                         rsp->data_out_res_cnt = cpu_to_be32(residual_count);
  89                 } else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
  90                         /* residual data from an overflow read */
  91                         rsp->flags = SRP_RSP_FLAG_DIOVER;
  92                         rsp->data_in_res_cnt = cpu_to_be32(residual_count);
  93                 }
  94         }
  95 }
  96
  97 /**
  98  * connection_broken() - Determine if the connection to the client is good
  99  * @vscsi:      Pointer to our adapter structure
 100  *
 101  * This function attempts to send a ping MAD to the client. If the call to
 102  * queue the request returns H_CLOSED then the connection has been broken
 103  * and the function returns TRUE.
 104  *
 105  * EXECUTION ENVIRONMENT:
 106  *      Interrupt or Process environment
 107  */
 108 static bool connection_broken(struct scsi_info *vscsi)
 109 {
 110         struct viosrp_crq *crq;
 111         u64 buffer[2] = { 0, 0 };
 112         long h_return_code;
 113         bool rc = false;
 114
 115         /* create a PING crq */
 116         crq = (struct viosrp_crq *)&buffer;
 117         crq->valid = VALID_CMD_RESP_EL;
 118         crq->format = MESSAGE_IN_CRQ;
 119         crq->status = PING;
 120
 121         h_return_code = h_send_crq(vscsi->dds.unit_id,
 122                                    cpu_to_be64(buffer[MSG_HI]),
 123                                    cpu_to_be64(buffer[MSG_LOW]));
 124
 125         pr_debug("connection_broken: rc %ld\n", h_return_code);
 126
 127         if (h_return_code == H_CLOSED)
 128                 rc = true;
 129
 130         return rc;
 131 }
 132
 133 /**
 134  * ibmvscsis_unregister_command_q() - Helper Function-Unregister Command Queue
 135  * @vscsi:      Pointer to our adapter structure
 136  *
 137  * This function calls h_free_q then frees the interrupt bit etc.
 138  * It must release the lock before doing so because of the time it can take
 139  * for h_free_crq in PHYP
 140  * NOTE: the caller must make sure that state and or flags will prevent
 141  *       interrupt handler from scheduling work.
 142  * NOTE: anyone calling this function may need to set the CRQ_CLOSED flag
 143  *       we can't do it here, because we don't have the lock
 144  *
 145  * EXECUTION ENVIRONMENT:
 146  *      Process level
 147  */
 148 static long ibmvscsis_unregister_command_q(struct scsi_info *vscsi)
 149 {
 150         long qrc;
 151         long rc = ADAPT_SUCCESS;
 152         int ticks = 0;
 153
 154         do {
 155                 qrc = h_free_crq(vscsi->dds.unit_id);
 156                 switch (qrc) {
 157                 case H_SUCCESS:
 158                         break;
 159
 160                 case H_HARDWARE:
 161                 case H_PARAMETER:
 162                         dev_err(&vscsi->dev, "unregister_command_q: error from h_free_crq %ld\n",
 163                                 qrc);
 164                         rc = ERROR;
 165                         break;
 166
 167                 case H_BUSY:
 168                 case H_LONG_BUSY_ORDER_1_MSEC:
 169                         /* msleep not good for small values */
 170                         usleep_range(1000, 2000);
 171                         ticks += 1;
 172                         break;
 173                 case H_LONG_BUSY_ORDER_10_MSEC:
 174                         usleep_range(10000, 20000);
 175                         ticks += 10;
 176                         break;
 177                 case H_LONG_BUSY_ORDER_100_MSEC:
 178                         msleep(100);
 179                         ticks += 100;
 180                         break;
 181                 case H_LONG_BUSY_ORDER_1_SEC:
 182                         ssleep(1);
 183                         ticks += 1000;
 184                         break;
 185                 case H_LONG_BUSY_ORDER_10_SEC:
 186                         ssleep(10);
 187                         ticks += 10000;
 188                         break;
 189                 case H_LONG_BUSY_ORDER_100_SEC:
 190                         ssleep(100);
 191                         ticks += 100000;
 192                         break;
 193                 default:
 194                         dev_err(&vscsi->dev, "unregister_command_q: unknown error %ld from h_free_crq\n",
 195                                 qrc);
 196                         rc = ERROR;
 197                         break;
 198                 }
 199
 200                 /*
 201                  * dont wait more then 300 seconds
 202                  * ticks are in milliseconds more or less
 203                  */
 204                 if (ticks > 300000 && qrc != H_SUCCESS) {
 205                         rc = ERROR;
 206                         dev_err(&vscsi->dev, "Excessive wait for h_free_crq\n");
 207                 }
 208         } while (qrc != H_SUCCESS && rc == ADAPT_SUCCESS);
 209
 210         pr_debug("Freeing CRQ: phyp rc %ld, rc %ld\n", qrc, rc);
 211
 212         return rc;
 213 }
 214
 215 /**
 216  * ibmvscsis_delete_client_info() - Helper function to Delete Client Info
 217  * @vscsi:      Pointer to our adapter structure
 218  * @client_closed:      True if client closed its queue
 219  *
 220  * Deletes information specific to the client when the client goes away
 221  *
 222  * EXECUTION ENVIRONMENT:
 223  *      Interrupt or Process
 224  */
 225 static void ibmvscsis_delete_client_info(struct scsi_info *vscsi,
 226                                          bool client_closed)
 227 {
 228         vscsi->client_cap = 0;
 229
 230         /*
 231          * Some things we don't want to clear if we're closing the queue,
 232          * because some clients don't resend the host handshake when they
 233          * get a transport event.
 234          */
 235         if (client_closed)
 236                 vscsi->client_data.os_type = 0;
 237 }
 238
 239 /**
 240  * ibmvscsis_free_command_q() - Free Command Queue
 241  * @vscsi:      Pointer to our adapter structure
 242  *
 243  * This function calls unregister_command_q, then clears interrupts and
 244  * any pending interrupt acknowledgments associated with the command q.
 245  * It also clears memory if there is no error.
 246  *
 247  * PHYP did not meet the PAPR architecture so that we must give up the
 248  * lock. This causes a timing hole regarding state change.  To close the
 249  * hole this routine does accounting on any change that occurred during
 250  * the time the lock is not held.
 251  * NOTE: must give up and then acquire the interrupt lock, the caller must
 252  *       make sure that state and or flags will prevent interrupt handler from
 253  *       scheduling work.
 254  *
 255  * EXECUTION ENVIRONMENT:
 256  *      Process level, interrupt lock is held
 257  */
 258 static long ibmvscsis_free_command_q(struct scsi_info *vscsi)
 259 {
 260         int bytes;
 261         u32 flags_under_lock;
 262         u16 state_under_lock;
 263         long rc = ADAPT_SUCCESS;
 264
 265         if (!(vscsi->flags & CRQ_CLOSED)) {
 266                 vio_disable_interrupts(vscsi->dma_dev);
 267
 268                 state_under_lock = vscsi->new_state;
 269                 flags_under_lock = vscsi->flags;
 270                 vscsi->phyp_acr_state = 0;
 271                 vscsi->phyp_acr_flags = 0;
 272
 273                 spin_unlock_bh(&vscsi->intr_lock);
 274                 rc = ibmvscsis_unregister_command_q(vscsi);
 275                 spin_lock_bh(&vscsi->intr_lock);
 276
 277                 if (state_under_lock != vscsi->new_state)
 278                         vscsi->phyp_acr_state = vscsi->new_state;
 279
 280                 vscsi->phyp_acr_flags = ((~flags_under_lock) & vscsi->flags);
 281
 282                 if (rc == ADAPT_SUCCESS) {
 283                         bytes = vscsi->cmd_q.size * PAGE_SIZE;
 284                         memset(vscsi->cmd_q.base_addr, 0, bytes);
 285                         vscsi->cmd_q.index = 0;
 286                         vscsi->flags |= CRQ_CLOSED;
 287
 288                         ibmvscsis_delete_client_info(vscsi, false);
 289                 }
 290
 291                 pr_debug("free_command_q: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
 292                          vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
 293                          vscsi->phyp_acr_state);
 294         }
 295         return rc;
 296 }
 297
 298 /**
 299  * ibmvscsis_cmd_q_dequeue() - Get valid Command element
 300  * @mask:       Mask to use in case index wraps
 301  * @current_index:      Current index into command queue
 302  * @base_addr:  Pointer to start of command queue
 303  *
 304  * Returns a pointer to a valid command element or NULL, if the command
 305  * queue is empty
 306  *
 307  * EXECUTION ENVIRONMENT:
 308  *      Interrupt environment, interrupt lock held
 309  */
 310 static struct viosrp_crq *ibmvscsis_cmd_q_dequeue(uint mask,
 311                                                   uint *current_index,
 312                                                   struct viosrp_crq *base_addr)
 313 {
 314         struct viosrp_crq *ptr;
 315
 316         ptr = base_addr + *current_index;
 317
 318         if (ptr->valid) {
 319                 *current_index = (*current_index + 1) & mask;
 320                 dma_rmb();
 321         } else {
 322                 ptr = NULL;
 323         }
 324
 325         return ptr;
 326 }
 327
 328 /**
 329  * ibmvscsis_send_init_message() - send initialize message to the client
 330  * @vscsi:      Pointer to our adapter structure
 331  * @format:     Which Init Message format to send
 332  *
 333  * EXECUTION ENVIRONMENT:
 334  *      Interrupt environment interrupt lock held
 335  */
 336 static long ibmvscsis_send_init_message(struct scsi_info *vscsi, u8 format)
 337 {
 338         struct viosrp_crq *crq;
 339         u64 buffer[2] = { 0, 0 };
 340         long rc;
 341
 342         crq = (struct viosrp_crq *)&buffer;
 343         crq->valid = VALID_INIT_MSG;
 344         crq->format = format;
 345         rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
 346                         cpu_to_be64(buffer[MSG_LOW]));
 347
 348         return rc;
 349 }
 350
 351 /**
 352  * ibmvscsis_check_init_msg() - Check init message valid
 353  * @vscsi:      Pointer to our adapter structure
 354  * @format:     Pointer to return format of Init Message, if any.
 355  *              Set to UNUSED_FORMAT if no Init Message in queue.
 356  *
 357  * Checks if an initialize message was queued by the initiatior
 358  * after the queue was created and before the interrupt was enabled.
 359  *
 360  * EXECUTION ENVIRONMENT:
 361  *      Process level only, interrupt lock held
 362  */
 363 static long ibmvscsis_check_init_msg(struct scsi_info *vscsi, uint *format)
 364 {
 365         struct viosrp_crq *crq;
 366         long rc = ADAPT_SUCCESS;
 367
 368         crq = ibmvscsis_cmd_q_dequeue(vscsi->cmd_q.mask, &vscsi->cmd_q.index,
 369                                       vscsi->cmd_q.base_addr);
 370         if (!crq) {
 371                 *format = (uint)UNUSED_FORMAT;
 372         } else if (crq->valid == VALID_INIT_MSG && crq->format == INIT_MSG) {
 373                 *format = (uint)INIT_MSG;
 374                 crq->valid = INVALIDATE_CMD_RESP_EL;
 375                 dma_rmb();
 376
 377                 /*
 378                  * the caller has ensured no initialize message was
 379                  * sent after the queue was
 380                  * created so there should be no other message on the queue.
 381                  */
 382                 crq = ibmvscsis_cmd_q_dequeue(vscsi->cmd_q.mask,
 383                                               &vscsi->cmd_q.index,
 384                                               vscsi->cmd_q.base_addr);
 385                 if (crq) {
 386                         *format = (uint)(crq->format);
 387                         rc = ERROR;
 388                         crq->valid = INVALIDATE_CMD_RESP_EL;
 389                         dma_rmb();
 390                 }
 391         } else {
 392                 *format = (uint)(crq->format);
 393                 rc = ERROR;
 394                 crq->valid = INVALIDATE_CMD_RESP_EL;
 395                 dma_rmb();
 396         }
 397
 398         return rc;
 399 }
 400
 401 /**
 402  * ibmvscsis_disconnect() - Helper function to disconnect
 403  * @work:       Pointer to work_struct, gives access to our adapter structure
 404  *
 405  * An error has occurred or the driver received a Transport event,
 406  * and the driver is requesting that the command queue be de-registered
 407  * in a safe manner. If there is no outstanding I/O then we can stop the
 408  * queue. If we are restarting the queue it will be reflected in the
 409  * the state of the adapter.
 410  *
 411  * EXECUTION ENVIRONMENT:
 412  *      Process environment
 413  */
 414 static void ibmvscsis_disconnect(struct work_struct *work)
 415 {
 416         struct scsi_info *vscsi = container_of(work, struct scsi_info,
 417                                                proc_work);
 418         u16 new_state;
 419         bool wait_idle = false;
 420
 421         spin_lock_bh(&vscsi->intr_lock);
 422         new_state = vscsi->new_state;
 423         vscsi->new_state = 0;
 424
 425         pr_debug("disconnect: flags 0x%x, state 0x%hx\n", vscsi->flags,
 426                  vscsi->state);
 427
 428         /*
 429          * check which state we are in and see if we
 430          * should transitition to the new state
 431          */
 432         switch (vscsi->state) {
 433         /* Should never be called while in this state. */
 434         case NO_QUEUE:
 435         /*
 436          * Can never transition from this state;
 437          * igonore errors and logout.
 438          */
 439         case UNCONFIGURING:
 440                 break;
 441
 442         /* can transition from this state to UNCONFIGURING */
 443         case ERR_DISCONNECT:
 444                 if (new_state == UNCONFIGURING)
 445                         vscsi->state = new_state;
 446                 break;
 447
 448         /*
 449          * Can transition from this state to to unconfiguring
 450          * or err disconnect.
 451          */
 452         case ERR_DISCONNECT_RECONNECT:
 453                 switch (new_state) {
 454                 case UNCONFIGURING:
 455                 case ERR_DISCONNECT:
 456                         vscsi->state = new_state;
 457                         break;
 458
 459                 case WAIT_IDLE:
 460                         break;
 461                 default:
 462                         break;
 463                 }
 464                 break;
 465
 466         /* can transition from this state to UNCONFIGURING */
 467         case ERR_DISCONNECTED:
 468                 if (new_state == UNCONFIGURING)
 469                         vscsi->state = new_state;
 470                 break;
 471
 472         case WAIT_ENABLED:
 473                 switch (new_state) {
 474                 case UNCONFIGURING:
 475                         vscsi->state = new_state;
 476                         vscsi->flags |= RESPONSE_Q_DOWN;
 477                         vscsi->flags &= ~(SCHEDULE_DISCONNECT |
 478                                           DISCONNECT_SCHEDULED);
 479                         dma_rmb();
 480                         if (vscsi->flags & CFG_SLEEPING) {
 481                                 vscsi->flags &= ~CFG_SLEEPING;
 482                                 complete(&vscsi->unconfig);
 483                         }
 484                         break;
 485
 486                 /* should never happen */
 487                 case ERR_DISCONNECT:
 488                 case ERR_DISCONNECT_RECONNECT:
 489                 case WAIT_IDLE:
 490                         dev_err(&vscsi->dev, "disconnect: invalid state %d for WAIT_IDLE\n",
 491                                 vscsi->state);
 492                         break;
 493                 }
 494                 break;
 495
 496         case WAIT_IDLE:
 497                 switch (new_state) {
 498                 case UNCONFIGURING:
 499                         vscsi->flags |= RESPONSE_Q_DOWN;
 500                         vscsi->state = new_state;
 501                         vscsi->flags &= ~(SCHEDULE_DISCONNECT |
 502                                           DISCONNECT_SCHEDULED);
 503                         ibmvscsis_free_command_q(vscsi);
 504                         break;
 505                 case ERR_DISCONNECT:
 506                 case ERR_DISCONNECT_RECONNECT:
 507                         vscsi->state = new_state;
 508                         break;
 509                 }
 510                 break;
 511
 512         /*
 513          * Initiator has not done a successful srp login
 514          * or has done a successful srp logout ( adapter was not
 515          * busy). In the first case there can be responses queued
 516          * waiting for space on the initiators response queue (MAD)
 517          * The second case the adapter is idle. Assume the worse case,
 518          * i.e. the second case.
 519          */
 520         case WAIT_CONNECTION:
 521         case CONNECTED:
 522         case SRP_PROCESSING:
 523                 wait_idle = true;
 524                 vscsi->state = new_state;
 525                 break;
 526
 527         /* can transition from this state to UNCONFIGURING */
 528         case UNDEFINED:
 529                 if (new_state == UNCONFIGURING)
 530                         vscsi->state = new_state;
 531                 break;
 532         default:
 533                 break;
 534         }
 535
 536         if (wait_idle) {
 537                 pr_debug("disconnect start wait, active %d, sched %d\n",
 538                          (int)list_empty(&vscsi->active_q),
 539                          (int)list_empty(&vscsi->schedule_q));
 540                 if (!list_empty(&vscsi->active_q) ||
 541                     !list_empty(&vscsi->schedule_q)) {
 542                         vscsi->flags |= WAIT_FOR_IDLE;
 543                         pr_debug("disconnect flags 0x%x\n", vscsi->flags);
 544                         /*
 545                          * This routine is can not be called with the interrupt
 546                          * lock held.
 547                          */
 548                         spin_unlock_bh(&vscsi->intr_lock);
 549                         wait_for_completion(&vscsi->wait_idle);
 550                         spin_lock_bh(&vscsi->intr_lock);
 551                 }
 552                 pr_debug("disconnect stop wait\n");
 553
 554                 ibmvscsis_adapter_idle(vscsi);
 555         }
 556
 557         spin_unlock_bh(&vscsi->intr_lock);
 558 }
 559
 560 /**
 561  * ibmvscsis_post_disconnect() - Schedule the disconnect
 562  * @vscsi:      Pointer to our adapter structure
 563  * @new_state:  State to move to after disconnecting
 564  * @flag_bits:  Flags to turn on in adapter structure
 565  *
 566  * If it's already been scheduled, then see if we need to "upgrade"
 567  * the new state (if the one passed in is more "severe" than the
 568  * previous one).
 569  *
 570  * PRECONDITION:
 571  *      interrupt lock is held
 572  */
 573 static void ibmvscsis_post_disconnect(struct scsi_info *vscsi, uint new_state,
 574                                       uint flag_bits)
 575 {
 576         uint state;
 577
 578         /* check the validity of the new state */
 579         switch (new_state) {
 580         case UNCONFIGURING:
 581         case ERR_DISCONNECT:
 582         case ERR_DISCONNECT_RECONNECT:
 583         case WAIT_IDLE:
 584                 break;
 585
 586         default:
 587                 dev_err(&vscsi->dev, "post_disconnect: Invalid new state %d\n",
 588                         new_state);
 589                 return;
 590         }
 591
 592         vscsi->flags |= flag_bits;
 593
 594         pr_debug("post_disconnect: new_state 0x%x, flag_bits 0x%x, vscsi->flags 0x%x, state %hx\n",
 595                  new_state, flag_bits, vscsi->flags, vscsi->state);
 596
 597         if (!(vscsi->flags & (DISCONNECT_SCHEDULED | SCHEDULE_DISCONNECT))) {
 598                 vscsi->flags |= SCHEDULE_DISCONNECT;
 599                 vscsi->new_state = new_state;
 600
 601                 INIT_WORK(&vscsi->proc_work, ibmvscsis_disconnect);
 602                 (void)queue_work(vscsi->work_q, &vscsi->proc_work);
 603         } else {
 604                 if (vscsi->new_state)
 605                         state = vscsi->new_state;
 606                 else
 607                         state = vscsi->state;
 608
 609                 switch (state) {
 610                 case NO_QUEUE:
 611                 case UNCONFIGURING:
 612                         break;
 613
 614                 case ERR_DISCONNECTED:
 615                 case ERR_DISCONNECT:
 616                 case UNDEFINED:
 617                         if (new_state == UNCONFIGURING)
 618                                 vscsi->new_state = new_state;
 619                         break;
 620
 621                 case ERR_DISCONNECT_RECONNECT:
 622                         switch (new_state) {
 623                         case UNCONFIGURING:
 624                         case ERR_DISCONNECT:
 625                                 vscsi->new_state = new_state;
 626                                 break;
 627                         default:
 628                                 break;
 629                         }
 630                         break;
 631
 632                 case WAIT_ENABLED:
 633                 case WAIT_IDLE:
 634                 case WAIT_CONNECTION:
 635                 case CONNECTED:
 636                 case SRP_PROCESSING:
 637                         vscsi->new_state = new_state;
 638                         break;
 639
 640                 default:
 641                         break;
 642                 }
 643         }
 644
 645         pr_debug("Leaving post_disconnect: flags 0x%x, new_state 0x%x\n",
 646                  vscsi->flags, vscsi->new_state);
 647 }
 648
 649 /**
 650  * ibmvscsis_handle_init_compl_msg() - Respond to an Init Complete Message
 651  * @vscsi:      Pointer to our adapter structure
 652  *
 653  * Must be called with interrupt lock held.
 654  */
 655 static long ibmvscsis_handle_init_compl_msg(struct scsi_info *vscsi)
 656 {
 657         long rc = ADAPT_SUCCESS;
 658
 659         switch (vscsi->state) {
 660         case NO_QUEUE:
 661         case ERR_DISCONNECT:
 662         case ERR_DISCONNECT_RECONNECT:
 663         case ERR_DISCONNECTED:
 664         case UNCONFIGURING:
 665         case UNDEFINED:
 666                 rc = ERROR;
 667                 break;
 668
 669         case WAIT_CONNECTION:
 670                 vscsi->state = CONNECTED;
 671                 break;
 672
 673         case WAIT_IDLE:
 674         case SRP_PROCESSING:
 675         case CONNECTED:
 676         case WAIT_ENABLED:
 677         default:
 678                 rc = ERROR;
 679                 dev_err(&vscsi->dev, "init_msg: invalid state %d to get init compl msg\n",
 680                         vscsi->state);
 681                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
 682                 break;
 683         }
 684
 685         return rc;
 686 }
 687
 688 /**
 689  * ibmvscsis_handle_init_msg() - Respond to an Init Message
 690  * @vscsi:      Pointer to our adapter structure
 691  *
 692  * Must be called with interrupt lock held.
 693  */
 694 static long ibmvscsis_handle_init_msg(struct scsi_info *vscsi)
 695 {
 696         long rc = ADAPT_SUCCESS;
 697
 698         switch (vscsi->state) {
 699         case WAIT_CONNECTION:
 700                 rc = ibmvscsis_send_init_message(vscsi, INIT_COMPLETE_MSG);
 701                 switch (rc) {
 702                 case H_SUCCESS:
 703                         vscsi->state = CONNECTED;
 704                         break;
 705
 706                 case H_PARAMETER:
 707                         dev_err(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
 708                                 rc);
 709                         ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
 710                         break;
 711
 712                 case H_DROPPED:
 713                         dev_err(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
 714                                 rc);
 715                         rc = ERROR;
 716                         ibmvscsis_post_disconnect(vscsi,
 717                                                   ERR_DISCONNECT_RECONNECT, 0);
 718                         break;
 719
 720                 case H_CLOSED:
 721                         pr_warn("init_msg: failed to send, rc %ld\n", rc);
 722                         rc = 0;
 723                         break;
 724                 }
 725                 break;
 726
 727         case UNDEFINED:
 728                 rc = ERROR;
 729                 break;
 730
 731         case UNCONFIGURING:
 732                 break;
 733
 734         case WAIT_ENABLED:
 735         case CONNECTED:
 736         case SRP_PROCESSING:
 737         case WAIT_IDLE:
 738         case NO_QUEUE:
 739         case ERR_DISCONNECT:
 740         case ERR_DISCONNECT_RECONNECT:
 741         case ERR_DISCONNECTED:
 742         default:
 743                 rc = ERROR;
 744                 dev_err(&vscsi->dev, "init_msg: invalid state %d to get init msg\n",
 745                         vscsi->state);
 746                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
 747                 break;
 748         }
 749
 750         return rc;
 751 }
 752
 753 /**
 754  * ibmvscsis_init_msg() - Respond to an init message
 755  * @vscsi:      Pointer to our adapter structure
 756  * @crq:        Pointer to CRQ element containing the Init Message
 757  *
 758  * EXECUTION ENVIRONMENT:
 759  *      Interrupt, interrupt lock held
 760  */
 761 static long ibmvscsis_init_msg(struct scsi_info *vscsi, struct viosrp_crq *crq)
 762 {
 763         long rc = ADAPT_SUCCESS;
 764
 765         pr_debug("init_msg: state 0x%hx\n", vscsi->state);
 766
 767         rc = h_vioctl(vscsi->dds.unit_id, H_GET_PARTNER_INFO,
 768                       (u64)vscsi->map_ioba | ((u64)PAGE_SIZE << 32), 0, 0, 0,
 769                       0);
 770         if (rc == H_SUCCESS) {
 771                 vscsi->client_data.partition_number =
 772                         be64_to_cpu(*(u64 *)vscsi->map_buf);
 773                 pr_debug("init_msg, part num %d\n",
 774                          vscsi->client_data.partition_number);
 775         } else {
 776                 pr_debug("init_msg h_vioctl rc %ld\n", rc);
 777                 rc = ADAPT_SUCCESS;
 778         }
 779
 780         if (crq->format == INIT_MSG) {
 781                 rc = ibmvscsis_handle_init_msg(vscsi);
 782         } else if (crq->format == INIT_COMPLETE_MSG) {
 783                 rc = ibmvscsis_handle_init_compl_msg(vscsi);
 784         } else {
 785                 rc = ERROR;
 786                 dev_err(&vscsi->dev, "init_msg: invalid format %d\n",
 787                         (uint)crq->format);
 788                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
 789         }
 790
 791         return rc;
 792 }
 793
 794 /**
 795  * ibmvscsis_establish_new_q() - Establish new CRQ queue
 796  * @vscsi:      Pointer to our adapter structure
 797  *
 798  * Must be called with interrupt lock held.
 799  */
 800 static long ibmvscsis_establish_new_q(struct scsi_info *vscsi)
 801 {
 802         long rc = ADAPT_SUCCESS;
 803         uint format;
 804
 805         vscsi->flags &= PRESERVE_FLAG_FIELDS;
 806         vscsi->rsp_q_timer.timer_pops = 0;
 807         vscsi->debit = 0;
 808         vscsi->credit = 0;
 809
 810         rc = vio_enable_interrupts(vscsi->dma_dev);
 811         if (rc) {
 812                 pr_warn("establish_new_q: failed to enable interrupts, rc %ld\n",
 813                         rc);
 814                 return rc;
 815         }
 816
 817         rc = ibmvscsis_check_init_msg(vscsi, &format);
 818         if (rc) {
 819                 dev_err(&vscsi->dev, "establish_new_q: check_init_msg failed, rc %ld\n",
 820                         rc);
 821                 return rc;
 822         }
 823
 824         if (format == UNUSED_FORMAT) {
 825                 rc = ibmvscsis_send_init_message(vscsi, INIT_MSG);
 826                 switch (rc) {
 827                 case H_SUCCESS:
 828                 case H_DROPPED:
 829                 case H_CLOSED:
 830                         rc = ADAPT_SUCCESS;
 831                         break;
 832
 833                 case H_PARAMETER:
 834                 case H_HARDWARE:
 835                         break;
 836
 837                 default:
 838                         vscsi->state = UNDEFINED;
 839                         rc = H_HARDWARE;
 840                         break;
 841                 }
 842         } else if (format == INIT_MSG) {
 843                 rc = ibmvscsis_handle_init_msg(vscsi);
 844         }
 845
 846         return rc;
 847 }
 848
 849 /**
 850  * ibmvscsis_reset_queue() - Reset CRQ Queue
 851  * @vscsi:      Pointer to our adapter structure
 852  *
 853  * This function calls h_free_q and then calls h_reg_q and does all
 854  * of the bookkeeping to get us back to where we can communicate.
 855  *
 856  * Actually, we don't always call h_free_crq.  A problem was discovered
 857  * where one partition would close and reopen his queue, which would
 858  * cause his partner to get a transport event, which would cause him to
 859  * close and reopen his queue, which would cause the original partition
 860  * to get a transport event, etc., etc.  To prevent this, we don't
 861  * actually close our queue if the client initiated the reset, (i.e.
 862  * either we got a transport event or we have detected that the client's
 863  * queue is gone)
 864  *
 865  * EXECUTION ENVIRONMENT:
 866  *      Process environment, called with interrupt lock held
 867  */
 868 static void ibmvscsis_reset_queue(struct scsi_info *vscsi)
 869 {
 870         int bytes;
 871         long rc = ADAPT_SUCCESS;
 872
 873         pr_debug("reset_queue: flags 0x%x\n", vscsi->flags);
 874
 875         /* don't reset, the client did it for us */
 876         if (vscsi->flags & (CLIENT_FAILED | TRANS_EVENT)) {
 877                 vscsi->flags &= PRESERVE_FLAG_FIELDS;
 878                 vscsi->rsp_q_timer.timer_pops = 0;
 879                 vscsi->debit = 0;
 880                 vscsi->credit = 0;
 881                 vscsi->state = WAIT_CONNECTION;
 882                 vio_enable_interrupts(vscsi->dma_dev);
 883         } else {
 884                 rc = ibmvscsis_free_command_q(vscsi);
 885                 if (rc == ADAPT_SUCCESS) {
 886                         vscsi->state = WAIT_CONNECTION;
 887
 888                         bytes = vscsi->cmd_q.size * PAGE_SIZE;
 889                         rc = h_reg_crq(vscsi->dds.unit_id,
 890                                        vscsi->cmd_q.crq_token, bytes);
 891                         if (rc == H_CLOSED || rc == H_SUCCESS) {
 892                                 rc = ibmvscsis_establish_new_q(vscsi);
 893                         }
 894
 895                         if (rc != ADAPT_SUCCESS) {
 896                                 pr_debug("reset_queue: reg_crq rc %ld\n", rc);
 897
 898                                 vscsi->state = ERR_DISCONNECTED;
 899                                 vscsi->flags |= RESPONSE_Q_DOWN;
 900                                 ibmvscsis_free_command_q(vscsi);
 901                         }
 902                 } else {
 903                         vscsi->state = ERR_DISCONNECTED;
 904                         vscsi->flags |= RESPONSE_Q_DOWN;
 905                 }
 906         }
 907 }
 908
 909 /**
 910  * ibmvscsis_free_cmd_resources() - Free command resources
 911  * @vscsi:      Pointer to our adapter structure
 912  * @cmd:        Command which is not longer in use
 913  *
 914  * Must be called with interrupt lock held.
 915  */
 916 static void ibmvscsis_free_cmd_resources(struct scsi_info *vscsi,
 917                                          struct ibmvscsis_cmd *cmd)
 918 {
 919         struct iu_entry *iue = cmd->iue;
 920
 921         switch (cmd->type) {
 922         case TASK_MANAGEMENT:
 923         case SCSI_CDB:
 924                 /*
 925                  * When the queue goes down this value is cleared, so it
 926                  * cannot be cleared in this general purpose function.
 927                  */
 928                 if (vscsi->debit)
 929                         vscsi->debit -= 1;
 930                 break;
 931         case ADAPTER_MAD:
 932                 vscsi->flags &= ~PROCESSING_MAD;
 933                 break;
 934         case UNSET_TYPE:
 935                 break;
 936         default:
 937                 dev_err(&vscsi->dev, "free_cmd_resources unknown type %d\n",
 938                         cmd->type);
 939                 break;
 940         }
 941
 942         cmd->iue = NULL;
 943         list_add_tail(&cmd->list, &vscsi->free_cmd);
 944         srp_iu_put(iue);
 945
 946         if (list_empty(&vscsi->active_q) && list_empty(&vscsi->schedule_q) &&
 947             list_empty(&vscsi->waiting_rsp) && (vscsi->flags & WAIT_FOR_IDLE)) {
 948                 vscsi->flags &= ~WAIT_FOR_IDLE;
 949                 complete(&vscsi->wait_idle);
 950         }
 951 }
 952
 953 /**
 954  * ibmvscsis_trans_event() - Handle a Transport Event
 955  * @vscsi:      Pointer to our adapter structure
 956  * @crq:        Pointer to CRQ entry containing the Transport Event
 957  *
 958  * Do the logic to close the I_T nexus.  This function may not
 959  * behave to specification.
 960  *
 961  * EXECUTION ENVIRONMENT:
 962  *      Interrupt, interrupt lock held
 963  */
 964 static long ibmvscsis_trans_event(struct scsi_info *vscsi,
 965                                   struct viosrp_crq *crq)
 966 {
 967         long rc = ADAPT_SUCCESS;
 968
 969         pr_debug("trans_event: format %d, flags 0x%x, state 0x%hx\n",
 970                  (int)crq->format, vscsi->flags, vscsi->state);
 971
 972         switch (crq->format) {
 973         case MIGRATED:
 974         case PARTNER_FAILED:
 975         case PARTNER_DEREGISTER:
 976                 ibmvscsis_delete_client_info(vscsi, true);
 977                 break;
 978
 979         default:
 980                 rc = ERROR;
 981                 dev_err(&vscsi->dev, "trans_event: invalid format %d\n",
 982                         (uint)crq->format);
 983                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT,
 984                                           RESPONSE_Q_DOWN);
 985                 break;
 986         }
 987
 988         if (rc == ADAPT_SUCCESS) {
 989                 switch (vscsi->state) {
 990                 case NO_QUEUE:
 991                 case ERR_DISCONNECTED:
 992                 case UNDEFINED:
 993                         break;
 994
 995                 case UNCONFIGURING:
 996                         vscsi->flags |= (RESPONSE_Q_DOWN | TRANS_EVENT);
 997                         break;
 998
 999                 case WAIT_ENABLED:
1000                         break;
1001
1002                 case WAIT_CONNECTION:
1003                         break;
1004
1005                 case CONNECTED:
1006                         ibmvscsis_post_disconnect(vscsi, WAIT_IDLE,
1007                                                   (RESPONSE_Q_DOWN |
1008                                                    TRANS_EVENT));
1009                         break;
1010
1011                 case SRP_PROCESSING:
1012                         if ((vscsi->debit > 0) ||
1013                             !list_empty(&vscsi->schedule_q) ||
1014                             !list_empty(&vscsi->waiting_rsp) ||
1015                             !list_empty(&vscsi->active_q)) {
1016                                 pr_debug("debit %d, sched %d, wait %d, active %d\n",
1017                                          vscsi->debit,
1018                                          (int)list_empty(&vscsi->schedule_q),
1019                                          (int)list_empty(&vscsi->waiting_rsp),
1020                                          (int)list_empty(&vscsi->active_q));
1021                                 pr_warn("connection lost with outstanding work\n");
1022                         } else {
1023                                 pr_debug("trans_event: SRP Processing, but no outstanding work\n");
1024                         }
1025
1026                         ibmvscsis_post_disconnect(vscsi, WAIT_IDLE,
1027                                                   (RESPONSE_Q_DOWN |
1028                                                    TRANS_EVENT));
1029                         break;
1030
1031                 case ERR_DISCONNECT:
1032                 case ERR_DISCONNECT_RECONNECT:
1033                 case WAIT_IDLE:
1034                         vscsi->flags |= (RESPONSE_Q_DOWN | TRANS_EVENT);
1035                         break;
1036                 }
1037         }
1038
1039         rc = vscsi->flags & SCHEDULE_DISCONNECT;
1040
1041         pr_debug("Leaving trans_event: flags 0x%x, state 0x%hx, rc %ld\n",
1042                  vscsi->flags, vscsi->state, rc);
1043
1044         return rc;
1045 }
1046
1047 /**
1048  * ibmvscsis_poll_cmd_q() - Poll Command Queue
1049  * @vscsi:      Pointer to our adapter structure
1050  *
1051  * Called to handle command elements that may have arrived while
1052  * interrupts were disabled.
1053  *
1054  * EXECUTION ENVIRONMENT:
1055  *      intr_lock must be held
1056  */
1057 static void ibmvscsis_poll_cmd_q(struct scsi_info *vscsi)
1058 {
1059         struct viosrp_crq *crq;
1060         long rc;
1061         bool ack = true;
1062         volatile u8 valid;
1063
1064         pr_debug("poll_cmd_q: flags 0x%x, state 0x%hx, q index %ud\n",
1065                  vscsi->flags, vscsi->state, vscsi->cmd_q.index);
1066
1067         rc = vscsi->flags & SCHEDULE_DISCONNECT;
1068         crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
1069         valid = crq->valid;
1070         dma_rmb();
1071
1072         while (valid) {
1073 poll_work:
1074                 vscsi->cmd_q.index =
1075                         (vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
1076
1077                 if (!rc) {
1078                         rc = ibmvscsis_parse_command(vscsi, crq);
1079                 } else {
1080                         if ((uint)crq->valid == VALID_TRANS_EVENT) {
1081                                 /*
1082                                  * must service the transport layer events even
1083                                  * in an error state, dont break out until all
1084                                  * the consecutive transport events have been
1085                                  * processed
1086                                  */
1087                                 rc = ibmvscsis_trans_event(vscsi, crq);
1088                         } else if (vscsi->flags & TRANS_EVENT) {
1089                                 /*
1090                                  * if a tranport event has occurred leave
1091                                  * everything but transport events on the queue
1092                                  */
1093                                 pr_debug("poll_cmd_q, ignoring\n");
1094
1095                                 /*
1096                                  * need to decrement the queue index so we can
1097                                  * look at the elment again
1098                                  */
1099                                 if (vscsi->cmd_q.index)
1100                                         vscsi->cmd_q.index -= 1;
1101                                 else
1102                                         /*
1103                                          * index is at 0 it just wrapped.
1104                                          * have it index last element in q
1105                                          */
1106                                         vscsi->cmd_q.index = vscsi->cmd_q.mask;
1107                                 break;
1108                         }
1109                 }
1110
1111                 crq->valid = INVALIDATE_CMD_RESP_EL;
1112
1113                 crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
1114                 valid = crq->valid;
1115                 dma_rmb();
1116         }
1117
1118         if (!rc) {
1119                 if (ack) {
1120                         vio_enable_interrupts(vscsi->dma_dev);
1121                         ack = false;
1122                         pr_debug("poll_cmd_q, reenabling interrupts\n");
1123                 }
1124                 valid = crq->valid;
1125                 dma_rmb();
1126                 if (valid)
1127                         goto poll_work;
1128         }
1129
1130         pr_debug("Leaving poll_cmd_q: rc %ld\n", rc);
1131 }
1132
1133 /**
1134  * ibmvscsis_free_cmd_qs() - Free elements in queue
1135  * @vscsi:      Pointer to our adapter structure
1136  *
1137  * Free all of the elements on all queues that are waiting for
1138  * whatever reason.
1139  *
1140  * PRECONDITION:
1141  *      Called with interrupt lock held
1142  */
1143 static void ibmvscsis_free_cmd_qs(struct scsi_info *vscsi)
1144 {
1145         struct ibmvscsis_cmd *cmd, *nxt;
1146
1147         pr_debug("free_cmd_qs: waiting_rsp empty %d, timer starter %d\n",
1148                  (int)list_empty(&vscsi->waiting_rsp),
1149                  vscsi->rsp_q_timer.started);
1150
1151         list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp, list) {
1152                 list_del(&cmd->list);
1153                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1154         }
1155 }
1156
1157 /**
1158  * ibmvscsis_get_free_cmd() - Get free command from list
1159  * @vscsi:      Pointer to our adapter structure
1160  *
1161  * Must be called with interrupt lock held.
1162  */
1163 static struct ibmvscsis_cmd *ibmvscsis_get_free_cmd(struct scsi_info *vscsi)
1164 {
1165         struct ibmvscsis_cmd *cmd = NULL;
1166         struct iu_entry *iue;
1167
1168         iue = srp_iu_get(&vscsi->target);
1169         if (iue) {
1170                 cmd = list_first_entry_or_null(&vscsi->free_cmd,
1171                                                struct ibmvscsis_cmd, list);
1172                 if (cmd) {
1173                         cmd->flags &= ~(DELAY_SEND);
1174                         list_del(&cmd->list);
1175                         cmd->iue = iue;
1176                         cmd->type = UNSET_TYPE;
1177                         memset(&cmd->se_cmd, 0, sizeof(cmd->se_cmd));
1178                 } else {
1179                         srp_iu_put(iue);
1180                 }
1181         }
1182
1183         return cmd;
1184 }
1185
1186 /**
1187  * ibmvscsis_adapter_idle() - Helper function to handle idle adapter
1188  * @vscsi:      Pointer to our adapter structure
1189  *
1190  * This function is called when the adapter is idle when the driver
1191  * is attempting to clear an error condition.
1192  * The adapter is considered busy if any of its cmd queues
1193  * are non-empty. This function can be invoked
1194  * from the off level disconnect function.
1195  *
1196  * EXECUTION ENVIRONMENT:
1197  *      Process environment called with interrupt lock held
1198  */
1199 static void ibmvscsis_adapter_idle(struct scsi_info *vscsi)
1200 {
1201         int free_qs = false;
1202
1203         pr_debug("adapter_idle: flags 0x%x, state 0x%hx\n", vscsi->flags,
1204                  vscsi->state);
1205
1206         /* Only need to free qs if we're disconnecting from client */
1207         if (vscsi->state != WAIT_CONNECTION || vscsi->flags & TRANS_EVENT)
1208                 free_qs = true;
1209
1210         switch (vscsi->state) {
1211         case UNCONFIGURING:
1212                 ibmvscsis_free_command_q(vscsi);
1213                 dma_rmb();
1214                 isync();
1215                 if (vscsi->flags & CFG_SLEEPING) {
1216                         vscsi->flags &= ~CFG_SLEEPING;
1217                         complete(&vscsi->unconfig);
1218                 }
1219                 break;
1220         case ERR_DISCONNECT_RECONNECT:
1221                 ibmvscsis_reset_queue(vscsi);
1222                 pr_debug("adapter_idle, disc_rec: flags 0x%x\n", vscsi->flags);
1223                 break;
1224
1225         case ERR_DISCONNECT:
1226                 ibmvscsis_free_command_q(vscsi);
1227                 vscsi->flags &= ~(SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED);
1228                 vscsi->flags |= RESPONSE_Q_DOWN;
1229                 if (vscsi->tport.enabled)
1230                         vscsi->state = ERR_DISCONNECTED;
1231                 else
1232                         vscsi->state = WAIT_ENABLED;
1233                 pr_debug("adapter_idle, disc: flags 0x%x, state 0x%hx\n",
1234                          vscsi->flags, vscsi->state);
1235                 break;
1236
1237         case WAIT_IDLE:
1238                 vscsi->rsp_q_timer.timer_pops = 0;
1239                 vscsi->debit = 0;
1240                 vscsi->credit = 0;
1241                 if (vscsi->flags & TRANS_EVENT) {
1242                         vscsi->state = WAIT_CONNECTION;
1243                         vscsi->flags &= PRESERVE_FLAG_FIELDS;
1244                 } else {
1245                         vscsi->state = CONNECTED;
1246                         vscsi->flags &= ~DISCONNECT_SCHEDULED;
1247                 }
1248
1249                 pr_debug("adapter_idle, wait: flags 0x%x, state 0x%hx\n",
1250                          vscsi->flags, vscsi->state);
1251                 ibmvscsis_poll_cmd_q(vscsi);
1252                 break;
1253
1254         case ERR_DISCONNECTED:
1255                 vscsi->flags &= ~DISCONNECT_SCHEDULED;
1256                 pr_debug("adapter_idle, disconnected: flags 0x%x, state 0x%hx\n",
1257                          vscsi->flags, vscsi->state);
1258                 break;
1259
1260         default:
1261                 dev_err(&vscsi->dev, "adapter_idle: in invalid state %d\n",
1262                         vscsi->state);
1263                 break;
1264         }
1265
1266         if (free_qs)
1267                 ibmvscsis_free_cmd_qs(vscsi);
1268
1269         /*
1270          * There is a timing window where we could lose a disconnect request.
1271          * The known path to this window occurs during the DISCONNECT_RECONNECT
1272          * case above: reset_queue calls free_command_q, which will release the
1273          * interrupt lock.  During that time, a new post_disconnect call can be
1274          * made with a "more severe" state (DISCONNECT or UNCONFIGURING).
1275          * Because the DISCONNECT_SCHEDULED flag is already set, post_disconnect
1276          * will only set the new_state.  Now free_command_q reacquires the intr
1277          * lock and clears the DISCONNECT_SCHEDULED flag (using PRESERVE_FLAG_
1278          * FIELDS), and the disconnect is lost.  This is particularly bad when
1279          * the new disconnect was for UNCONFIGURING, since the unconfigure hangs
1280          * forever.
1281          * Fix is that free command queue sets acr state and acr flags if there
1282          * is a change under the lock
1283          * note free command queue writes to this state it clears it
1284          * before releasing the lock, different drivers call the free command
1285          * queue different times so dont initialize above
1286          */
1287         if (vscsi->phyp_acr_state != 0) {
1288                 /*
1289                  * set any bits in flags that may have been cleared by
1290                  * a call to free command queue in switch statement
1291                  * or reset queue
1292                  */
1293                 vscsi->flags |= vscsi->phyp_acr_flags;
1294                 ibmvscsis_post_disconnect(vscsi, vscsi->phyp_acr_state, 0);
1295                 vscsi->phyp_acr_state = 0;
1296                 vscsi->phyp_acr_flags = 0;
1297
1298                 pr_debug("adapter_idle: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
1299                          vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
1300                          vscsi->phyp_acr_state);
1301         }
1302
1303         pr_debug("Leaving adapter_idle: flags 0x%x, state 0x%hx, new_state 0x%x\n",
1304                  vscsi->flags, vscsi->state, vscsi->new_state);
1305 }
1306
1307 /**
1308  * ibmvscsis_copy_crq_packet() - Copy CRQ Packet
1309  * @vscsi:      Pointer to our adapter structure
1310  * @cmd:        Pointer to command element to use to process the request
1311  * @crq:        Pointer to CRQ entry containing the request
1312  *
1313  * Copy the srp information unit from the hosted
1314  * partition using remote dma
1315  *
1316  * EXECUTION ENVIRONMENT:
1317  *      Interrupt, interrupt lock held
1318  */
1319 static long ibmvscsis_copy_crq_packet(struct scsi_info *vscsi,
1320                                       struct ibmvscsis_cmd *cmd,
1321                                       struct viosrp_crq *crq)
1322 {
1323         struct iu_entry *iue = cmd->iue;
1324         long rc = 0;
1325         u16 len;
1326
1327         len = be16_to_cpu(crq->IU_length);
1328         if ((len > SRP_MAX_IU_LEN) || (len == 0)) {
1329                 dev_err(&vscsi->dev, "copy_crq: Invalid len %d passed", len);
1330                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1331                 return SRP_VIOLATION;
1332         }
1333
1334         rc = h_copy_rdma(len, vscsi->dds.window[REMOTE].liobn,
1335                          be64_to_cpu(crq->IU_data_ptr),
1336                          vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma);
1337
1338         switch (rc) {
1339         case H_SUCCESS:
1340                 cmd->init_time = mftb();
1341                 iue->remote_token = crq->IU_data_ptr;
1342                 iue->iu_len = len;
1343                 pr_debug("copy_crq: ioba 0x%llx, init_time 0x%llx\n",
1344                          be64_to_cpu(crq->IU_data_ptr), cmd->init_time);
1345                 break;
1346         case H_PERMISSION:
1347                 if (connection_broken(vscsi))
1348                         ibmvscsis_post_disconnect(vscsi,
1349                                                   ERR_DISCONNECT_RECONNECT,
1350                                                   (RESPONSE_Q_DOWN |
1351                                                    CLIENT_FAILED));
1352                 else
1353                         ibmvscsis_post_disconnect(vscsi,
1354                                                   ERR_DISCONNECT_RECONNECT, 0);
1355
1356                 dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
1357                         rc);
1358                 break;
1359         case H_DEST_PARM:
1360         case H_SOURCE_PARM:
1361         default:
1362                 dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
1363                         rc);
1364                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1365                 break;
1366         }
1367
1368         return rc;
1369 }
1370
1371 /**
1372  * ibmvscsis_adapter_info - Service an Adapter Info MAnagement Data gram
1373  * @vscsi:      Pointer to our adapter structure
1374  * @iue:        Information Unit containing the Adapter Info MAD request
1375  *
1376  * EXECUTION ENVIRONMENT:
1377  *      Interrupt adapter lock is held
1378  */
1379 static long ibmvscsis_adapter_info(struct scsi_info *vscsi,
1380                                    struct iu_entry *iue)
1381 {
1382         struct viosrp_adapter_info *mad = &vio_iu(iue)->mad.adapter_info;
1383         struct mad_adapter_info_data *info;
1384         uint flag_bits = 0;
1385         dma_addr_t token;
1386         long rc;
1387
1388         mad->common.status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1389
1390         if (be16_to_cpu(mad->common.length) > sizeof(*info)) {
1391                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1392                 return 0;
1393         }
1394
1395         info = dma_alloc_coherent(&vscsi->dma_dev->dev, sizeof(*info), &token,
1396                                   GFP_ATOMIC);
1397         if (!info) {
1398                 dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
1399                         iue->target);
1400                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1401                 return 0;
1402         }
1403
1404         /* Get remote info */
1405         rc = h_copy_rdma(be16_to_cpu(mad->common.length),
1406                          vscsi->dds.window[REMOTE].liobn,
1407                          be64_to_cpu(mad->buffer),
1408                          vscsi->dds.window[LOCAL].liobn, token);
1409
1410         if (rc != H_SUCCESS) {
1411                 if (rc == H_PERMISSION) {
1412                         if (connection_broken(vscsi))
1413                                 flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1414                 }
1415                 pr_warn("adapter_info: h_copy_rdma from client failed, rc %ld\n",
1416                         rc);
1417                 pr_debug("adapter_info: ioba 0x%llx, flags 0x%x, flag_bits 0x%x\n",
1418                          be64_to_cpu(mad->buffer), vscsi->flags, flag_bits);
1419                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1420                                           flag_bits);
1421                 goto free_dma;
1422         }
1423
1424         /*
1425          * Copy client info, but ignore partition number, which we
1426          * already got from phyp - unless we failed to get it from
1427          * phyp (e.g. if we're running on a p5 system).
1428          */
1429         if (vscsi->client_data.partition_number == 0)
1430                 vscsi->client_data.partition_number =
1431                         be32_to_cpu(info->partition_number);
1432         strncpy(vscsi->client_data.srp_version, info->srp_version,
1433                 sizeof(vscsi->client_data.srp_version));
1434         strncpy(vscsi->client_data.partition_name, info->partition_name,
1435                 sizeof(vscsi->client_data.partition_name));
1436         vscsi->client_data.mad_version = be32_to_cpu(info->mad_version);
1437         vscsi->client_data.os_type = be32_to_cpu(info->os_type);
1438
1439         /* Copy our info */
1440         strncpy(info->srp_version, SRP_VERSION,
1441                 sizeof(info->srp_version));
1442         strncpy(info->partition_name, vscsi->dds.partition_name,
1443                 sizeof(info->partition_name));
1444         info->partition_number = cpu_to_be32(vscsi->dds.partition_num);
1445         info->mad_version = cpu_to_be32(MAD_VERSION_1);
1446         info->os_type = cpu_to_be32(LINUX);
1447         memset(&info->port_max_txu[0], 0, sizeof(info->port_max_txu));
1448         info->port_max_txu[0] = cpu_to_be32(MAX_TXU);
1449
1450         dma_wmb();
1451         rc = h_copy_rdma(sizeof(*info), vscsi->dds.window[LOCAL].liobn,
1452                          token, vscsi->dds.window[REMOTE].liobn,
1453                          be64_to_cpu(mad->buffer));
1454         switch (rc) {
1455         case H_SUCCESS:
1456                 break;
1457
1458         case H_SOURCE_PARM:
1459         case H_DEST_PARM:
1460         case H_PERMISSION:
1461                 if (connection_broken(vscsi))
1462                         flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1463         default:
1464                 dev_err(&vscsi->dev, "adapter_info: h_copy_rdma to client failed, rc %ld\n",
1465                         rc);
1466                 ibmvscsis_post_disconnect(vscsi,
1467                                           ERR_DISCONNECT_RECONNECT,
1468                                           flag_bits);
1469                 break;
1470         }
1471
1472 free_dma:
1473         dma_free_coherent(&vscsi->dma_dev->dev, sizeof(*info), info, token);
1474         pr_debug("Leaving adapter_info, rc %ld\n", rc);
1475
1476         return rc;
1477 }
1478
1479 /**
1480  * ibmvscsis_cap_mad() - Service a Capabilities MAnagement Data gram
1481  * @vscsi:      Pointer to our adapter structure
1482  * @iue:        Information Unit containing the Capabilities MAD request
1483  *
1484  * NOTE: if you return an error from this routine you must be
1485  * disconnecting or you will cause a hang
1486  *
1487  * EXECUTION ENVIRONMENT:
1488  *      Interrupt called with adapter lock held
1489  */
1490 static int ibmvscsis_cap_mad(struct scsi_info *vscsi, struct iu_entry *iue)
1491 {
1492         struct viosrp_capabilities *mad = &vio_iu(iue)->mad.capabilities;
1493         struct capabilities *cap;
1494         struct mad_capability_common *common;
1495         dma_addr_t token;
1496         u16 olen, len, status, min_len, cap_len;
1497         u32 flag;
1498         uint flag_bits = 0;
1499         long rc = 0;
1500
1501         olen = be16_to_cpu(mad->common.length);
1502         /*
1503          * struct capabilities hardcodes a couple capabilities after the
1504          * header, but the capabilities can actually be in any order.
1505          */
1506         min_len = offsetof(struct capabilities, migration);
1507         if ((olen < min_len) || (olen > PAGE_SIZE)) {
1508                 pr_warn("cap_mad: invalid len %d\n", olen);
1509                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1510                 return 0;
1511         }
1512
1513         cap = dma_alloc_coherent(&vscsi->dma_dev->dev, olen, &token,
1514                                  GFP_ATOMIC);
1515         if (!cap) {
1516                 dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
1517                         iue->target);
1518                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1519                 return 0;
1520         }
1521         rc = h_copy_rdma(olen, vscsi->dds.window[REMOTE].liobn,
1522                          be64_to_cpu(mad->buffer),
1523                          vscsi->dds.window[LOCAL].liobn, token);
1524         if (rc == H_SUCCESS) {
1525                 strncpy(cap->name, dev_name(&vscsi->dma_dev->dev),
1526                         SRP_MAX_LOC_LEN);
1527
1528                 len = olen - min_len;
1529                 status = VIOSRP_MAD_SUCCESS;
1530                 common = (struct mad_capability_common *)&cap->migration;
1531
1532                 while ((len > 0) && (status == VIOSRP_MAD_SUCCESS) && !rc) {
1533                         pr_debug("cap_mad: len left %hd, cap type %d, cap len %hd\n",
1534                                  len, be32_to_cpu(common->cap_type),
1535                                  be16_to_cpu(common->length));
1536
1537                         cap_len = be16_to_cpu(common->length);
1538                         if (cap_len > len) {
1539                                 dev_err(&vscsi->dev, "cap_mad: cap len mismatch with total len\n");
1540                                 status = VIOSRP_MAD_FAILED;
1541                                 break;
1542                         }
1543
1544                         if (cap_len == 0) {
1545                                 dev_err(&vscsi->dev, "cap_mad: cap len is 0\n");
1546                                 status = VIOSRP_MAD_FAILED;
1547                                 break;
1548                         }
1549
1550                         switch (common->cap_type) {
1551                         default:
1552                                 pr_debug("cap_mad: unsupported capability\n");
1553                                 common->server_support = 0;
1554                                 flag = cpu_to_be32((u32)CAP_LIST_SUPPORTED);
1555                                 cap->flags &= ~flag;
1556                                 break;
1557                         }
1558
1559                         len = len - cap_len;
1560                         common = (struct mad_capability_common *)
1561                                 ((char *)common + cap_len);
1562                 }
1563
1564                 mad->common.status = cpu_to_be16(status);
1565
1566                 dma_wmb();
1567                 rc = h_copy_rdma(olen, vscsi->dds.window[LOCAL].liobn, token,
1568                                  vscsi->dds.window[REMOTE].liobn,
1569                                  be64_to_cpu(mad->buffer));
1570
1571                 if (rc != H_SUCCESS) {
1572                         pr_debug("cap_mad: failed to copy to client, rc %ld\n",
1573                                  rc);
1574
1575                         if (rc == H_PERMISSION) {
1576                                 if (connection_broken(vscsi))
1577                                         flag_bits = (RESPONSE_Q_DOWN |
1578                                                      CLIENT_FAILED);
1579                         }
1580
1581                         pr_warn("cap_mad: error copying data to client, rc %ld\n",
1582                                 rc);
1583                         ibmvscsis_post_disconnect(vscsi,
1584                                                   ERR_DISCONNECT_RECONNECT,
1585                                                   flag_bits);
1586                 }
1587         }
1588
1589         dma_free_coherent(&vscsi->dma_dev->dev, olen, cap, token);
1590
1591         pr_debug("Leaving cap_mad, rc %ld, client_cap 0x%x\n",
1592                  rc, vscsi->client_cap);
1593
1594         return rc;
1595 }
1596
1597 /**
1598  * ibmvscsis_process_mad() - Service a MAnagement Data gram
1599  * @vscsi:      Pointer to our adapter structure
1600  * @iue:        Information Unit containing the MAD request
1601  *
1602  * Must be called with interrupt lock held.
1603  */
1604 static long ibmvscsis_process_mad(struct scsi_info *vscsi, struct iu_entry *iue)
1605 {
1606         struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
1607         struct viosrp_empty_iu *empty;
1608         long rc = ADAPT_SUCCESS;
1609
1610         switch (be32_to_cpu(mad->type)) {
1611         case VIOSRP_EMPTY_IU_TYPE:
1612                 empty = &vio_iu(iue)->mad.empty_iu;
1613                 vscsi->empty_iu_id = be64_to_cpu(empty->buffer);
1614                 vscsi->empty_iu_tag = be64_to_cpu(empty->common.tag);
1615                 mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1616                 break;
1617         case VIOSRP_ADAPTER_INFO_TYPE:
1618                 rc = ibmvscsis_adapter_info(vscsi, iue);
1619                 break;
1620         case VIOSRP_CAPABILITIES_TYPE:
1621                 rc = ibmvscsis_cap_mad(vscsi, iue);
1622                 break;
1623         case VIOSRP_ENABLE_FAST_FAIL:
1624                 if (vscsi->state == CONNECTED) {
1625                         vscsi->fast_fail = true;
1626                         mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1627                 } else {
1628                         pr_warn("fast fail mad sent after login\n");
1629                         mad->status = cpu_to_be16(VIOSRP_MAD_FAILED);
1630                 }
1631                 break;
1632         default:
1633                 mad->status = cpu_to_be16(VIOSRP_MAD_NOT_SUPPORTED);
1634                 break;
1635         }
1636
1637         return rc;
1638 }
1639
1640 /**
1641  * srp_snd_msg_failed() - Handle an error when sending a response
1642  * @vscsi:      Pointer to our adapter structure
1643  * @rc:         The return code from the h_send_crq command
1644  *
1645  * Must be called with interrupt lock held.
1646  */
1647 static void srp_snd_msg_failed(struct scsi_info *vscsi, long rc)
1648 {
1649         ktime_t kt;
1650
1651         if (rc != H_DROPPED) {
1652                 ibmvscsis_free_cmd_qs(vscsi);
1653
1654                 if (rc == H_CLOSED)
1655                         vscsi->flags |= CLIENT_FAILED;
1656
1657                 /* don't flag the same problem multiple times */
1658                 if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
1659                         vscsi->flags |= RESPONSE_Q_DOWN;
1660                         if (!(vscsi->state & (ERR_DISCONNECT |
1661                                               ERR_DISCONNECT_RECONNECT |
1662                                               ERR_DISCONNECTED | UNDEFINED))) {
1663                                 dev_err(&vscsi->dev, "snd_msg_failed: setting RESPONSE_Q_DOWN, state 0x%hx, flags 0x%x, rc %ld\n",
1664                                         vscsi->state, vscsi->flags, rc);
1665                         }
1666                         ibmvscsis_post_disconnect(vscsi,
1667                                                   ERR_DISCONNECT_RECONNECT, 0);
1668                 }
1669                 return;
1670         }
1671
1672         /*
1673          * The response queue is full.
1674          * If the server is processing SRP requests, i.e.
1675          * the client has successfully done an
1676          * SRP_LOGIN, then it will wait forever for room in
1677          * the queue.  However if the system admin
1678          * is attempting to unconfigure the server then one
1679          * or more children will be in a state where
1680          * they are being removed. So if there is even one
1681          * child being removed then the driver assumes
1682          * the system admin is attempting to break the
1683          * connection with the client and MAX_TIMER_POPS
1684          * is honored.
1685          */
1686         if ((vscsi->rsp_q_timer.timer_pops < MAX_TIMER_POPS) ||
1687             (vscsi->state == SRP_PROCESSING)) {
1688                 pr_debug("snd_msg_failed: response queue full, flags 0x%x, timer started %d, pops %d\n",
1689                          vscsi->flags, (int)vscsi->rsp_q_timer.started,
1690                          vscsi->rsp_q_timer.timer_pops);
1691
1692                 /*
1693                  * Check if the timer is running; if it
1694                  * is not then start it up.
1695                  */
1696                 if (!vscsi->rsp_q_timer.started) {
1697                         if (vscsi->rsp_q_timer.timer_pops <
1698                             MAX_TIMER_POPS) {
1699                                 kt = WAIT_NANO_SECONDS;
1700                         } else {
1701                                 /*
1702                                  * slide the timeslice if the maximum
1703                                  * timer pops have already happened
1704                                  */
1705                                 kt = ktime_set(WAIT_SECONDS, 0);
1706                         }
1707
1708                         vscsi->rsp_q_timer.started = true;
1709                         hrtimer_start(&vscsi->rsp_q_timer.timer, kt,
1710                                       HRTIMER_MODE_REL);
1711                 }
1712         } else {
1713                 /*
1714                  * TBD: Do we need to worry about this? Need to get
1715                  *      remove working.
1716                  */
1717                 /*
1718                  * waited a long time and it appears the system admin
1719                  * is bring this driver down
1720                  */
1721                 vscsi->flags |= RESPONSE_Q_DOWN;
1722                 ibmvscsis_free_cmd_qs(vscsi);
1723                 /*
1724                  * if the driver is already attempting to disconnect
1725                  * from the client and has already logged an error
1726                  * trace this event but don't put it in the error log
1727                  */
1728                 if (!(vscsi->state & (ERR_DISCONNECT |
1729                                       ERR_DISCONNECT_RECONNECT |
1730                                       ERR_DISCONNECTED | UNDEFINED))) {
1731                         dev_err(&vscsi->dev, "client crq full too long\n");
1732                         ibmvscsis_post_disconnect(vscsi,
1733                                                   ERR_DISCONNECT_RECONNECT,
1734                                                   0);
1735                 }
1736         }
1737 }
1738
1739 /**
1740  * ibmvscsis_send_messages() - Send a Response
1741  * @vscsi:      Pointer to our adapter structure
1742  *
1743  * Send a response, first checking the waiting queue. Responses are
1744  * sent in order they are received. If the response cannot be sent,
1745  * because the client queue is full, it stays on the waiting queue.
1746  *
1747  * PRECONDITION:
1748  *      Called with interrupt lock held
1749  */
1750 static void ibmvscsis_send_messages(struct scsi_info *vscsi)
1751 {
1752         u64 msg_hi = 0;
1753         /* note do not attempt to access the IU_data_ptr with this pointer
1754          * it is not valid
1755          */
1756         struct viosrp_crq *crq = (struct viosrp_crq *)&msg_hi;
1757         struct ibmvscsis_cmd *cmd, *nxt;
1758         struct iu_entry *iue;
1759         long rc = ADAPT_SUCCESS;
1760         bool retry = false;
1761
1762         if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
1763                 do {
1764                         retry = false;
1765                         list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp,
1766                                                  list) {
1767                                 /*
1768                                  * Check to make sure abort cmd gets processed
1769                                  * prior to the abort tmr cmd
1770                                  */
1771                                 if (cmd->flags & DELAY_SEND)
1772                                         continue;
1773
1774                                 if (cmd->abort_cmd) {
1775                                         retry = true;
1776                                         cmd->abort_cmd->flags &= ~(DELAY_SEND);
1777                                 }
1778
1779                                 /*
1780                                  * If CMD_T_ABORTED w/o CMD_T_TAS scenarios and
1781                                  * the case where LIO issued a
1782                                  * ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST
1783                                  * case then we dont send a response, since it
1784                                  * was already done.
1785                                  */
1786                                 if (cmd->se_cmd.transport_state & CMD_T_ABORTED &&
1787                                     !(cmd->se_cmd.transport_state & CMD_T_TAS)) {
1788                                         list_del(&cmd->list);
1789                                         ibmvscsis_free_cmd_resources(vscsi,
1790                                                                      cmd);
1791                                 } else {
1792                                         iue = cmd->iue;
1793
1794                                         crq->valid = VALID_CMD_RESP_EL;
1795                                         crq->format = cmd->rsp.format;
1796
1797                                         if (cmd->flags & CMD_FAST_FAIL)
1798                                                 crq->status = VIOSRP_ADAPTER_FAIL;
1799
1800                                         crq->IU_length = cpu_to_be16(cmd->rsp.len);
1801
1802                                         rc = h_send_crq(vscsi->dma_dev->unit_address,
1803                                                         be64_to_cpu(msg_hi),
1804                                                         be64_to_cpu(cmd->rsp.tag));
1805
1806                                         pr_debug("send_messages: cmd %p, tag 0x%llx, rc %ld\n",
1807                                                  cmd, be64_to_cpu(cmd->rsp.tag), rc);
1808
1809                                         /* if all ok free up the command
1810                                          * element resources
1811                                          */
1812                                         if (rc == H_SUCCESS) {
1813                                                 /* some movement has occurred */
1814                                                 vscsi->rsp_q_timer.timer_pops = 0;
1815                                                 list_del(&cmd->list);
1816
1817                                                 ibmvscsis_free_cmd_resources(vscsi,
1818                                                                              cmd);
1819                                         } else {
1820                                                 srp_snd_msg_failed(vscsi, rc);
1821                                                 break;
1822                                         }
1823                                 }
1824                         }
1825                 } while (retry);
1826
1827                 if (!rc) {
1828                         /*
1829                          * The timer could pop with the queue empty.  If
1830                          * this happens, rc will always indicate a
1831                          * success; clear the pop count.
1832                          */
1833                         vscsi->rsp_q_timer.timer_pops = 0;
1834                 }
1835         } else {
1836                 ibmvscsis_free_cmd_qs(vscsi);
1837         }
1838 }
1839
1840 /* Called with intr lock held */
1841 static void ibmvscsis_send_mad_resp(struct scsi_info *vscsi,
1842                                     struct ibmvscsis_cmd *cmd,
1843                                     struct viosrp_crq *crq)
1844 {
1845         struct iu_entry *iue = cmd->iue;
1846         struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
1847         uint flag_bits = 0;
1848         long rc;
1849
1850         dma_wmb();
1851         rc = h_copy_rdma(sizeof(struct mad_common),
1852                          vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
1853                          vscsi->dds.window[REMOTE].liobn,
1854                          be64_to_cpu(crq->IU_data_ptr));
1855         if (!rc) {
1856                 cmd->rsp.format = VIOSRP_MAD_FORMAT;
1857                 cmd->rsp.len = sizeof(struct mad_common);
1858                 cmd->rsp.tag = mad->tag;
1859                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
1860                 ibmvscsis_send_messages(vscsi);
1861         } else {
1862                 pr_debug("Error sending mad response, rc %ld\n", rc);
1863                 if (rc == H_PERMISSION) {
1864                         if (connection_broken(vscsi))
1865                                 flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1866                 }
1867                 dev_err(&vscsi->dev, "mad: failed to copy to client, rc %ld\n",
1868                         rc);
1869
1870                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1871                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1872                                           flag_bits);
1873         }
1874 }
1875
1876 /**
1877  * ibmvscsis_mad() - Service a MAnagement Data gram.
1878  * @vscsi:      Pointer to our adapter structure
1879  * @crq:        Pointer to the CRQ entry containing the MAD request
1880  *
1881  * EXECUTION ENVIRONMENT:
1882  *      Interrupt, called with adapter lock held
1883  */
1884 static long ibmvscsis_mad(struct scsi_info *vscsi, struct viosrp_crq *crq)
1885 {
1886         struct iu_entry *iue;
1887         struct ibmvscsis_cmd *cmd;
1888         struct mad_common *mad;
1889         long rc = ADAPT_SUCCESS;
1890
1891         switch (vscsi->state) {
1892                 /*
1893                  * We have not exchanged Init Msgs yet, so this MAD was sent
1894                  * before the last Transport Event; client will not be
1895                  * expecting a response.
1896                  */
1897         case WAIT_CONNECTION:
1898                 pr_debug("mad: in Wait Connection state, ignoring MAD, flags %d\n",
1899                          vscsi->flags);
1900                 return ADAPT_SUCCESS;
1901
1902         case SRP_PROCESSING:
1903         case CONNECTED:
1904                 break;
1905
1906                 /*
1907                  * We should never get here while we're in these states.
1908                  * Just log an error and get out.
1909                  */
1910         case UNCONFIGURING:
1911         case WAIT_IDLE:
1912         case ERR_DISCONNECT:
1913         case ERR_DISCONNECT_RECONNECT:
1914         default:
1915                 dev_err(&vscsi->dev, "mad: invalid adapter state %d for mad\n",
1916                         vscsi->state);
1917                 return ADAPT_SUCCESS;
1918         }
1919
1920         cmd = ibmvscsis_get_free_cmd(vscsi);
1921         if (!cmd) {
1922                 dev_err(&vscsi->dev, "mad: failed to get cmd, debit %d\n",
1923                         vscsi->debit);
1924                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1925                 return ERROR;
1926         }
1927         iue = cmd->iue;
1928         cmd->type = ADAPTER_MAD;
1929
1930         rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
1931         if (!rc) {
1932                 mad = (struct mad_common *)&vio_iu(iue)->mad;
1933
1934                 pr_debug("mad: type %d\n", be32_to_cpu(mad->type));
1935
1936                 rc = ibmvscsis_process_mad(vscsi, iue);
1937
1938                 pr_debug("mad: status %hd, rc %ld\n", be16_to_cpu(mad->status),
1939                          rc);
1940
1941                 if (!rc)
1942                         ibmvscsis_send_mad_resp(vscsi, cmd, crq);
1943         } else {
1944                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1945         }
1946
1947         pr_debug("Leaving mad, rc %ld\n", rc);
1948         return rc;
1949 }
1950
1951 /**
1952  * ibmvscsis_login_rsp() - Create/copy a login response notice to the client
1953  * @vscsi:      Pointer to our adapter structure
1954  * @cmd:        Pointer to the command for the SRP Login request
1955  *
1956  * EXECUTION ENVIRONMENT:
1957  *      Interrupt, interrupt lock held
1958  */
1959 static long ibmvscsis_login_rsp(struct scsi_info *vscsi,
1960                                 struct ibmvscsis_cmd *cmd)
1961 {
1962         struct iu_entry *iue = cmd->iue;
1963         struct srp_login_rsp *rsp = &vio_iu(iue)->srp.login_rsp;
1964         struct format_code *fmt;
1965         uint flag_bits = 0;
1966         long rc = ADAPT_SUCCESS;
1967
1968         memset(rsp, 0, sizeof(struct srp_login_rsp));
1969
1970         rsp->opcode = SRP_LOGIN_RSP;
1971         rsp->req_lim_delta = cpu_to_be32(vscsi->request_limit);
1972         rsp->tag = cmd->rsp.tag;
1973         rsp->max_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
1974         rsp->max_ti_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
1975         fmt = (struct format_code *)&rsp->buf_fmt;
1976         fmt->buffers = SUPPORTED_FORMATS;
1977         vscsi->credit = 0;
1978
1979         cmd->rsp.len = sizeof(struct srp_login_rsp);
1980
1981         dma_wmb();
1982         rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
1983                          iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
1984                          be64_to_cpu(iue->remote_token));
1985
1986         switch (rc) {
1987         case H_SUCCESS:
1988                 break;
1989
1990         case H_PERMISSION:
1991                 if (connection_broken(vscsi))
1992                         flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
1993                 dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
1994                         rc);
1995                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1996                                           flag_bits);
1997                 break;
1998         case H_SOURCE_PARM:
1999         case H_DEST_PARM:
2000         default:
2001                 dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
2002                         rc);
2003                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2004                 break;
2005         }
2006
2007         return rc;
2008 }
2009
2010 /**
2011  * ibmvscsis_srp_login_rej() - Create/copy a login rejection notice to client
2012  * @vscsi:      Pointer to our adapter structure
2013  * @cmd:        Pointer to the command for the SRP Login request
2014  * @reason:     The reason the SRP Login is being rejected, per SRP protocol
2015  *
2016  * EXECUTION ENVIRONMENT:
2017  *      Interrupt, interrupt lock held
2018  */
2019 static long ibmvscsis_srp_login_rej(struct scsi_info *vscsi,
2020                                     struct ibmvscsis_cmd *cmd, u32 reason)
2021 {
2022         struct iu_entry *iue = cmd->iue;
2023         struct srp_login_rej *rej = &vio_iu(iue)->srp.login_rej;
2024         struct format_code *fmt;
2025         uint flag_bits = 0;
2026         long rc = ADAPT_SUCCESS;
2027
2028         memset(rej, 0, sizeof(*rej));
2029
2030         rej->opcode = SRP_LOGIN_REJ;
2031         rej->reason = cpu_to_be32(reason);
2032         rej->tag = cmd->rsp.tag;
2033         fmt = (struct format_code *)&rej->buf_fmt;
2034         fmt->buffers = SUPPORTED_FORMATS;
2035
2036         cmd->rsp.len = sizeof(*rej);
2037
2038         dma_wmb();
2039         rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
2040                          iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
2041                          be64_to_cpu(iue->remote_token));
2042
2043         switch (rc) {
2044         case H_SUCCESS:
2045                 break;
2046         case H_PERMISSION:
2047                 if (connection_broken(vscsi))
2048                         flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
2049                 dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
2050                         rc);
2051                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
2052                                           flag_bits);
2053                 break;
2054         case H_SOURCE_PARM:
2055         case H_DEST_PARM:
2056         default:
2057                 dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
2058                         rc);
2059                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2060                 break;
2061         }
2062
2063         return rc;
2064 }
2065
2066 static int ibmvscsis_make_nexus(struct ibmvscsis_tport *tport)
2067 {
2068         char *name = tport->tport_name;
2069         struct ibmvscsis_nexus *nexus;
2070         int rc;
2071
2072         if (tport->ibmv_nexus) {
2073                 pr_debug("tport->ibmv_nexus already exists\n");
2074                 return 0;
2075         }
2076
2077         nexus = kzalloc(sizeof(*nexus), GFP_KERNEL);
2078         if (!nexus) {
2079                 pr_err("Unable to allocate struct ibmvscsis_nexus\n");
2080                 return -ENOMEM;
2081         }
2082
2083         nexus->se_sess = target_alloc_session(&tport->se_tpg, 0, 0,
2084                                               TARGET_PROT_NORMAL, name, nexus,
2085                                               NULL);
2086         if (IS_ERR(nexus->se_sess)) {
2087                 rc = PTR_ERR(nexus->se_sess);
2088                 goto transport_init_fail;
2089         }
2090
2091         tport->ibmv_nexus = nexus;
2092
2093         return 0;
2094
2095 transport_init_fail:
2096         kfree(nexus);
2097         return rc;
2098 }
2099
2100 static int ibmvscsis_drop_nexus(struct ibmvscsis_tport *tport)
2101 {
2102         struct se_session *se_sess;
2103         struct ibmvscsis_nexus *nexus;
2104
2105         nexus = tport->ibmv_nexus;
2106         if (!nexus)
2107                 return -ENODEV;
2108
2109         se_sess = nexus->se_sess;
2110         if (!se_sess)
2111                 return -ENODEV;
2112
2113         /*
2114          * Release the SCSI I_T Nexus to the emulated ibmvscsis Target Port
2115          */
2116         target_wait_for_sess_cmds(se_sess);
2117         transport_deregister_session_configfs(se_sess);
2118         transport_deregister_session(se_sess);
2119         tport->ibmv_nexus = NULL;
2120         kfree(nexus);
2121
2122         return 0;
2123 }
2124
2125 /**
2126  * ibmvscsis_srp_login() - Process an SRP Login Request
2127  * @vscsi:      Pointer to our adapter structure
2128  * @cmd:        Command element to use to process the SRP Login request
2129  * @crq:        Pointer to CRQ entry containing the SRP Login request
2130  *
2131  * EXECUTION ENVIRONMENT:
2132  *      Interrupt, called with interrupt lock held
2133  */
2134 static long ibmvscsis_srp_login(struct scsi_info *vscsi,
2135                                 struct ibmvscsis_cmd *cmd,
2136                                 struct viosrp_crq *crq)
2137 {
2138         struct iu_entry *iue = cmd->iue;
2139         struct srp_login_req *req = &vio_iu(iue)->srp.login_req;
2140         struct port_id {
2141                 __be64 id_extension;
2142                 __be64 io_guid;
2143         } *iport, *tport;
2144         struct format_code *fmt;
2145         u32 reason = 0x0;
2146         long rc = ADAPT_SUCCESS;
2147
2148         iport = (struct port_id *)req->initiator_port_id;
2149         tport = (struct port_id *)req->target_port_id;
2150         fmt = (struct format_code *)&req->req_buf_fmt;
2151         if (be32_to_cpu(req->req_it_iu_len) > SRP_MAX_IU_LEN)
2152                 reason = SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE;
2153         else if (be32_to_cpu(req->req_it_iu_len) < 64)
2154                 reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
2155         else if ((be64_to_cpu(iport->id_extension) > (MAX_NUM_PORTS - 1)) ||
2156                  (be64_to_cpu(tport->id_extension) > (MAX_NUM_PORTS - 1)))
2157                 reason = SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL;
2158         else if (req->req_flags & SRP_MULTICHAN_MULTI)
2159                 reason = SRP_LOGIN_REJ_MULTI_CHANNEL_UNSUPPORTED;
2160         else if (fmt->buffers & (~SUPPORTED_FORMATS))
2161                 reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
2162         else if ((fmt->buffers & SUPPORTED_FORMATS) == 0)
2163                 reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
2164
2165         if (vscsi->state == SRP_PROCESSING)
2166                 reason = SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED;
2167
2168         rc = ibmvscsis_make_nexus(&vscsi->tport);
2169         if (rc)
2170                 reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
2171
2172         cmd->rsp.format = VIOSRP_SRP_FORMAT;
2173         cmd->rsp.tag = req->tag;
2174
2175         pr_debug("srp_login: reason 0x%x\n", reason);
2176
2177         if (reason)
2178                 rc = ibmvscsis_srp_login_rej(vscsi, cmd, reason);
2179         else
2180                 rc = ibmvscsis_login_rsp(vscsi, cmd);
2181
2182         if (!rc) {
2183                 if (!reason)
2184                         vscsi->state = SRP_PROCESSING;
2185
2186                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
2187                 ibmvscsis_send_messages(vscsi);
2188         } else {
2189                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2190         }
2191
2192         pr_debug("Leaving srp_login, rc %ld\n", rc);
2193         return rc;
2194 }
2195
2196 /**
2197  * ibmvscsis_srp_i_logout() - Helper Function to close I_T Nexus
2198  * @vscsi:      Pointer to our adapter structure
2199  * @cmd:        Command element to use to process the Implicit Logout request
2200  * @crq:        Pointer to CRQ entry containing the Implicit Logout request
2201  *
2202  * Do the logic to close the I_T nexus.  This function may not
2203  * behave to specification.
2204  *
2205  * EXECUTION ENVIRONMENT:
2206  *      Interrupt, interrupt lock held
2207  */
2208 static long ibmvscsis_srp_i_logout(struct scsi_info *vscsi,
2209                                    struct ibmvscsis_cmd *cmd,
2210                                    struct viosrp_crq *crq)
2211 {
2212         struct iu_entry *iue = cmd->iue;
2213         struct srp_i_logout *log_out = &vio_iu(iue)->srp.i_logout;
2214         long rc = ADAPT_SUCCESS;
2215
2216         if ((vscsi->debit > 0) || !list_empty(&vscsi->schedule_q) ||
2217             !list_empty(&vscsi->waiting_rsp)) {
2218                 dev_err(&vscsi->dev, "i_logout: outstanding work\n");
2219                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
2220         } else {
2221                 cmd->rsp.format = SRP_FORMAT;
2222                 cmd->rsp.tag = log_out->tag;
2223                 cmd->rsp.len = sizeof(struct mad_common);
2224                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
2225                 ibmvscsis_send_messages(vscsi);
2226
2227                 ibmvscsis_post_disconnect(vscsi, WAIT_IDLE, 0);
2228         }
2229
2230         return rc;
2231 }
2232
2233 /* Called with intr lock held */
2234 static void ibmvscsis_srp_cmd(struct scsi_info *vscsi, struct viosrp_crq *crq)
2235 {
2236         struct ibmvscsis_cmd *cmd;
2237         struct iu_entry *iue;
2238         struct srp_cmd *srp;
2239         struct srp_tsk_mgmt *tsk;
2240         long rc;
2241
2242         if (vscsi->request_limit - vscsi->debit <= 0) {
2243                 /* Client has exceeded request limit */
2244                 dev_err(&vscsi->dev, "Client exceeded the request limit (%d), debit %d\n",
2245                         vscsi->request_limit, vscsi->debit);
2246                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2247                 return;
2248         }
2249
2250         cmd = ibmvscsis_get_free_cmd(vscsi);
2251         if (!cmd) {
2252                 dev_err(&vscsi->dev, "srp_cmd failed to get cmd, debit %d\n",
2253                         vscsi->debit);
2254                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2255                 return;
2256         }
2257         iue = cmd->iue;
2258         srp = &vio_iu(iue)->srp.cmd;
2259
2260         rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
2261         if (rc) {
2262                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2263                 return;
2264         }
2265
2266         if (vscsi->state == SRP_PROCESSING) {
2267                 switch (srp->opcode) {
2268                 case SRP_LOGIN_REQ:
2269                         rc = ibmvscsis_srp_login(vscsi, cmd, crq);
2270                         break;
2271
2272                 case SRP_TSK_MGMT:
2273                         tsk = &vio_iu(iue)->srp.tsk_mgmt;
2274                         pr_debug("tsk_mgmt tag: %llu (0x%llx)\n", tsk->tag,
2275                                  tsk->tag);
2276                         cmd->rsp.tag = tsk->tag;
2277                         vscsi->debit += 1;
2278                         cmd->type = TASK_MANAGEMENT;
2279                         list_add_tail(&cmd->list, &vscsi->schedule_q);
2280                         queue_work(vscsi->work_q, &cmd->work);
2281                         break;
2282
2283                 case SRP_CMD:
2284                         pr_debug("srp_cmd tag: %llu (0x%llx)\n", srp->tag,
2285                                  srp->tag);
2286                         cmd->rsp.tag = srp->tag;
2287                         vscsi->debit += 1;
2288                         cmd->type = SCSI_CDB;
2289                         /*
2290                          * We want to keep track of work waiting for
2291                          * the workqueue.
2292                          */
2293                         list_add_tail(&cmd->list, &vscsi->schedule_q);
2294                         queue_work(vscsi->work_q, &cmd->work);
2295                         break;
2296
2297                 case SRP_I_LOGOUT:
2298                         rc = ibmvscsis_srp_i_logout(vscsi, cmd, crq);
2299                         break;
2300
2301                 case SRP_CRED_RSP:
2302                 case SRP_AER_RSP:
2303                 default:
2304                         ibmvscsis_free_cmd_resources(vscsi, cmd);
2305                         dev_err(&vscsi->dev, "invalid srp cmd, opcode %d\n",
2306                                 (uint)srp->opcode);
2307                         ibmvscsis_post_disconnect(vscsi,
2308                                                   ERR_DISCONNECT_RECONNECT, 0);
2309                         break;
2310                 }
2311         } else if (srp->opcode == SRP_LOGIN_REQ && vscsi->state == CONNECTED) {
2312                 rc = ibmvscsis_srp_login(vscsi, cmd, crq);
2313         } else {
2314                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2315                 dev_err(&vscsi->dev, "Invalid state %d to handle srp cmd\n",
2316                         vscsi->state);
2317                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2318         }
2319 }
2320
2321 /**
2322  * ibmvscsis_ping_response() - Respond to a ping request
2323  * @vscsi:      Pointer to our adapter structure
2324  *
2325  * Let the client know that the server is alive and waiting on
2326  * its native I/O stack.
2327  * If any type of error occurs from the call to queue a ping
2328  * response then the client is either not accepting or receiving
2329  * interrupts.  Disconnect with an error.
2330  *
2331  * EXECUTION ENVIRONMENT:
2332  *      Interrupt, interrupt lock held
2333  */
2334 static long ibmvscsis_ping_response(struct scsi_info *vscsi)
2335 {
2336         struct viosrp_crq *crq;
2337         u64 buffer[2] = { 0, 0 };
2338         long rc;
2339
2340         crq = (struct viosrp_crq *)&buffer;
2341         crq->valid = VALID_CMD_RESP_EL;
2342         crq->format = (u8)MESSAGE_IN_CRQ;
2343         crq->status = PING_RESPONSE;
2344
2345         rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
2346                         cpu_to_be64(buffer[MSG_LOW]));
2347
2348         switch (rc) {
2349         case H_SUCCESS:
2350                 break;
2351         case H_CLOSED:
2352                 vscsi->flags |= CLIENT_FAILED;
2353         case H_DROPPED:
2354                 vscsi->flags |= RESPONSE_Q_DOWN;
2355         case H_REMOTE_PARM:
2356                 dev_err(&vscsi->dev, "ping_response: h_send_crq failed, rc %ld\n",
2357                         rc);
2358                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2359                 break;
2360         default:
2361                 dev_err(&vscsi->dev, "ping_response: h_send_crq returned unknown rc %ld\n",
2362                         rc);
2363                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
2364                 break;
2365         }
2366
2367         return rc;
2368 }
2369
2370 /**
2371  * ibmvscsis_parse_command() - Parse an element taken from the cmd rsp queue.
2372  * @vscsi:      Pointer to our adapter structure
2373  * @crq:        Pointer to CRQ element containing the SRP request
2374  *
2375  * This function will return success if the command queue element is valid
2376  * and the srp iu or MAD request it pointed to was also valid.  That does
2377  * not mean that an error was not returned to the client.
2378  *
2379  * EXECUTION ENVIRONMENT:
2380  *      Interrupt, intr lock held
2381  */
2382 static long ibmvscsis_parse_command(struct scsi_info *vscsi,
2383                                     struct viosrp_crq *crq)
2384 {
2385         long rc = ADAPT_SUCCESS;
2386
2387         switch (crq->valid) {
2388         case VALID_CMD_RESP_EL:
2389                 switch (crq->format) {
2390                 case OS400_FORMAT:
2391                 case AIX_FORMAT:
2392                 case LINUX_FORMAT:
2393                 case MAD_FORMAT:
2394                         if (vscsi->flags & PROCESSING_MAD) {
2395                                 rc = ERROR;
2396                                 dev_err(&vscsi->dev, "parse_command: already processing mad\n");
2397                                 ibmvscsis_post_disconnect(vscsi,
2398                                                        ERR_DISCONNECT_RECONNECT,
2399                                                        0);
2400                         } else {
2401                                 vscsi->flags |= PROCESSING_MAD;
2402                                 rc = ibmvscsis_mad(vscsi, crq);
2403                         }
2404                         break;
2405
2406                 case SRP_FORMAT:
2407                         ibmvscsis_srp_cmd(vscsi, crq);
2408                         break;
2409
2410                 case MESSAGE_IN_CRQ:
2411                         if (crq->status == PING)
2412                                 ibmvscsis_ping_response(vscsi);
2413                         break;
2414
2415                 default:
2416                         dev_err(&vscsi->dev, "parse_command: invalid format %d\n",
2417                                 (uint)crq->format);
2418                         ibmvscsis_post_disconnect(vscsi,
2419                                                   ERR_DISCONNECT_RECONNECT, 0);
2420                         break;
2421                 }
2422                 break;
2423
2424         case VALID_TRANS_EVENT:
2425                 rc = ibmvscsis_trans_event(vscsi, crq);
2426                 break;
2427
2428         case VALID_INIT_MSG:
2429                 rc = ibmvscsis_init_msg(vscsi, crq);
2430                 break;
2431
2432         default:
2433                 dev_err(&vscsi->dev, "parse_command: invalid valid field %d\n",
2434                         (uint)crq->valid);
2435                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2436                 break;
2437         }
2438
2439         /*
2440          * Return only what the interrupt handler cares
2441          * about. Most errors we keep right on trucking.
2442          */
2443         rc = vscsi->flags & SCHEDULE_DISCONNECT;
2444
2445         return rc;
2446 }
2447
2448 static int read_dma_window(struct scsi_info *vscsi)
2449 {
2450         struct vio_dev *vdev = vscsi->dma_dev;
2451         const __be32 *dma_window;
2452         const __be32 *prop;
2453
2454         /* TODO Using of_parse_dma_window would be better, but it doesn't give
2455          * a way to read multiple windows without already knowing the size of
2456          * a window or the number of windows.
2457          */
2458         dma_window = (const __be32 *)vio_get_attribute(vdev,
2459                                                        "ibm,my-dma-window",
2460                                                        NULL);
2461         if (!dma_window) {
2462                 pr_err("Couldn't find ibm,my-dma-window property\n");
2463                 return -1;
2464         }
2465
2466         vscsi->dds.window[LOCAL].liobn = be32_to_cpu(*dma_window);
2467         dma_window++;
2468
2469         prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-address-cells",
2470                                                  NULL);
2471         if (!prop) {
2472                 pr_warn("Couldn't find ibm,#dma-address-cells property\n");
2473                 dma_window++;
2474         } else {
2475                 dma_window += be32_to_cpu(*prop);
2476         }
2477
2478         prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-size-cells",
2479                                                  NULL);
2480         if (!prop) {
2481                 pr_warn("Couldn't find ibm,#dma-size-cells property\n");
2482                 dma_window++;
2483         } else {
2484                 dma_window += be32_to_cpu(*prop);
2485         }
2486
2487         /* dma_window should point to the second window now */
2488         vscsi->dds.window[REMOTE].liobn = be32_to_cpu(*dma_window);
2489
2490         return 0;
2491 }
2492
2493 static struct ibmvscsis_tport *ibmvscsis_lookup_port(const char *name)
2494 {
2495         struct ibmvscsis_tport *tport = NULL;
2496         struct vio_dev *vdev;
2497         struct scsi_info *vscsi;
2498
2499         spin_lock_bh(&ibmvscsis_dev_lock);
2500         list_for_each_entry(vscsi, &ibmvscsis_dev_list, list) {
2501                 vdev = vscsi->dma_dev;
2502                 if (!strcmp(dev_name(&vdev->dev), name)) {
2503                         tport = &vscsi->tport;
2504                         break;
2505                 }
2506         }
2507         spin_unlock_bh(&ibmvscsis_dev_lock);
2508
2509         return tport;
2510 }
2511
2512 /**
2513  * ibmvscsis_parse_cmd() - Parse SRP Command
2514  * @vscsi:      Pointer to our adapter structure
2515  * @cmd:        Pointer to command element with SRP command
2516  *
2517  * Parse the srp command; if it is valid then submit it to tcm.
2518  * Note: The return code does not reflect the status of the SCSI CDB.
2519  *
2520  * EXECUTION ENVIRONMENT:
2521  *      Process level
2522  */
2523 static void ibmvscsis_parse_cmd(struct scsi_info *vscsi,
2524                                 struct ibmvscsis_cmd *cmd)
2525 {
2526         struct iu_entry *iue = cmd->iue;
2527         struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
2528         struct ibmvscsis_nexus *nexus;
2529         u64 data_len = 0;
2530         enum dma_data_direction dir;
2531         int attr = 0;
2532         int rc = 0;
2533
2534         nexus = vscsi->tport.ibmv_nexus;
2535         /*
2536          * additional length in bytes.  Note that the SRP spec says that
2537          * additional length is in 4-byte words, but technically the
2538          * additional length field is only the upper 6 bits of the byte.
2539          * The lower 2 bits are reserved.  If the lower 2 bits are 0 (as
2540          * all reserved fields should be), then interpreting the byte as
2541          * an int will yield the length in bytes.
2542          */
2543         if (srp->add_cdb_len & 0x03) {
2544                 dev_err(&vscsi->dev, "parse_cmd: reserved bits set in IU\n");
2545                 spin_lock_bh(&vscsi->intr_lock);
2546                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2547                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2548                 spin_unlock_bh(&vscsi->intr_lock);
2549                 return;
2550         }
2551
2552         if (srp_get_desc_table(srp, &dir, &data_len)) {
2553                 dev_err(&vscsi->dev, "0x%llx: parsing SRP descriptor table failed.\n",
2554                         srp->tag);
2555                 goto fail;
2556         }
2557
2558         cmd->rsp.sol_not = srp->sol_not;
2559
2560         switch (srp->task_attr) {
2561         case SRP_SIMPLE_TASK:
2562                 attr = TCM_SIMPLE_TAG;
2563                 break;
2564         case SRP_ORDERED_TASK:
2565                 attr = TCM_ORDERED_TAG;
2566                 break;
2567         case SRP_HEAD_TASK:
2568                 attr = TCM_HEAD_TAG;
2569                 break;
2570         case SRP_ACA_TASK:
2571                 attr = TCM_ACA_TAG;
2572                 break;
2573         default:
2574                 dev_err(&vscsi->dev, "Invalid task attribute %d\n",
2575                         srp->task_attr);
2576                 goto fail;
2577         }
2578
2579         cmd->se_cmd.tag = be64_to_cpu(srp->tag);
2580
2581         spin_lock_bh(&vscsi->intr_lock);
2582         list_add_tail(&cmd->list, &vscsi->active_q);
2583         spin_unlock_bh(&vscsi->intr_lock);
2584
2585         srp->lun.scsi_lun[0] &= 0x3f;
2586
2587         rc = target_submit_cmd(&cmd->se_cmd, nexus->se_sess, srp->cdb,
2588                                cmd->sense_buf, scsilun_to_int(&srp->lun),
2589                                data_len, attr, dir, 0);
2590         if (rc) {
2591                 dev_err(&vscsi->dev, "target_submit_cmd failed, rc %d\n", rc);
2592                 spin_lock_bh(&vscsi->intr_lock);
2593                 list_del(&cmd->list);
2594                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2595                 spin_unlock_bh(&vscsi->intr_lock);
2596                 goto fail;
2597         }
2598         return;
2599
2600 fail:
2601         spin_lock_bh(&vscsi->intr_lock);
2602         ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2603         spin_unlock_bh(&vscsi->intr_lock);
2604 }
2605
2606 /**
2607  * ibmvscsis_parse_task() - Parse SRP Task Management Request
2608  * @vscsi:      Pointer to our adapter structure
2609  * @cmd:        Pointer to command element with SRP task management request
2610  *
2611  * Parse the srp task management request; if it is valid then submit it to tcm.
2612  * Note: The return code does not reflect the status of the task management
2613  * request.
2614  *
2615  * EXECUTION ENVIRONMENT:
2616  *      Processor level
2617  */
2618 static void ibmvscsis_parse_task(struct scsi_info *vscsi,
2619                                  struct ibmvscsis_cmd *cmd)
2620 {
2621         struct iu_entry *iue = cmd->iue;
2622         struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
2623         int tcm_type;
2624         u64 tag_to_abort = 0;
2625         int rc = 0;
2626         struct ibmvscsis_nexus *nexus;
2627
2628         nexus = vscsi->tport.ibmv_nexus;
2629
2630         cmd->rsp.sol_not = srp_tsk->sol_not;
2631
2632         switch (srp_tsk->tsk_mgmt_func) {
2633         case SRP_TSK_ABORT_TASK:
2634                 tcm_type = TMR_ABORT_TASK;
2635                 tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
2636                 break;
2637         case SRP_TSK_ABORT_TASK_SET:
2638                 tcm_type = TMR_ABORT_TASK_SET;
2639                 break;
2640         case SRP_TSK_CLEAR_TASK_SET:
2641                 tcm_type = TMR_CLEAR_TASK_SET;
2642                 break;
2643         case SRP_TSK_LUN_RESET:
2644                 tcm_type = TMR_LUN_RESET;
2645                 break;
2646         case SRP_TSK_CLEAR_ACA:
2647                 tcm_type = TMR_CLEAR_ACA;
2648                 break;
2649         default:
2650                 dev_err(&vscsi->dev, "unknown task mgmt func %d\n",
2651                         srp_tsk->tsk_mgmt_func);
2652                 cmd->se_cmd.se_tmr_req->response =
2653                         TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2654                 rc = -1;
2655                 break;
2656         }
2657
2658         if (!rc) {
2659                 cmd->se_cmd.tag = be64_to_cpu(srp_tsk->tag);
2660
2661                 spin_lock_bh(&vscsi->intr_lock);
2662                 list_add_tail(&cmd->list, &vscsi->active_q);
2663                 spin_unlock_bh(&vscsi->intr_lock);
2664
2665                 srp_tsk->lun.scsi_lun[0] &= 0x3f;
2666
2667                 pr_debug("calling submit_tmr, func %d\n",
2668                          srp_tsk->tsk_mgmt_func);
2669                 rc = target_submit_tmr(&cmd->se_cmd, nexus->se_sess, NULL,
2670                                        scsilun_to_int(&srp_tsk->lun), srp_tsk,
2671                                        tcm_type, GFP_KERNEL, tag_to_abort, 0);
2672                 if (rc) {
2673                         dev_err(&vscsi->dev, "target_submit_tmr failed, rc %d\n",
2674                                 rc);
2675                         spin_lock_bh(&vscsi->intr_lock);
2676                         list_del(&cmd->list);
2677                         spin_unlock_bh(&vscsi->intr_lock);
2678                         cmd->se_cmd.se_tmr_req->response =
2679                                 TMR_FUNCTION_REJECTED;
2680                 }
2681         }
2682
2683         if (rc)
2684                 transport_send_check_condition_and_sense(&cmd->se_cmd, 0, 0);
2685 }
2686
2687 static void ibmvscsis_scheduler(struct work_struct *work)
2688 {
2689         struct ibmvscsis_cmd *cmd = container_of(work, struct ibmvscsis_cmd,
2690                                                  work);
2691         struct scsi_info *vscsi = cmd->adapter;
2692
2693         spin_lock_bh(&vscsi->intr_lock);
2694
2695         /* Remove from schedule_q */
2696         list_del(&cmd->list);
2697
2698         /* Don't submit cmd if we're disconnecting */
2699         if (vscsi->flags & (SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED)) {
2700                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2701
2702                 /* ibmvscsis_disconnect might be waiting for us */
2703                 if (list_empty(&vscsi->active_q) &&
2704                     list_empty(&vscsi->schedule_q) &&
2705                     (vscsi->flags & WAIT_FOR_IDLE)) {
2706                         vscsi->flags &= ~WAIT_FOR_IDLE;
2707                         complete(&vscsi->wait_idle);
2708                 }
2709
2710                 spin_unlock_bh(&vscsi->intr_lock);
2711                 return;
2712         }
2713
2714         spin_unlock_bh(&vscsi->intr_lock);
2715
2716         switch (cmd->type) {
2717         case SCSI_CDB:
2718                 ibmvscsis_parse_cmd(vscsi, cmd);
2719                 break;
2720         case TASK_MANAGEMENT:
2721                 ibmvscsis_parse_task(vscsi, cmd);
2722                 break;
2723         default:
2724                 dev_err(&vscsi->dev, "scheduler, invalid cmd type %d\n",
2725                         cmd->type);
2726                 spin_lock_bh(&vscsi->intr_lock);
2727                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2728                 spin_unlock_bh(&vscsi->intr_lock);
2729                 break;
2730         }
2731 }
2732
2733 static int ibmvscsis_alloc_cmds(struct scsi_info *vscsi, int num)
2734 {
2735         struct ibmvscsis_cmd *cmd;
2736         int i;
2737
2738         INIT_LIST_HEAD(&vscsi->free_cmd);
2739         vscsi->cmd_pool = kcalloc(num, sizeof(struct ibmvscsis_cmd),
2740                                   GFP_KERNEL);
2741         if (!vscsi->cmd_pool)
2742                 return -ENOMEM;
2743
2744         for (i = 0, cmd = (struct ibmvscsis_cmd *)vscsi->cmd_pool; i < num;
2745              i++, cmd++) {
2746                 cmd->abort_cmd = NULL;
2747                 cmd->adapter = vscsi;
2748                 INIT_WORK(&cmd->work, ibmvscsis_scheduler);
2749                 list_add_tail(&cmd->list, &vscsi->free_cmd);
2750         }
2751
2752         return 0;
2753 }
2754
2755 static void ibmvscsis_free_cmds(struct scsi_info *vscsi)
2756 {
2757         kfree(vscsi->cmd_pool);
2758         vscsi->cmd_pool = NULL;
2759         INIT_LIST_HEAD(&vscsi->free_cmd);
2760 }
2761
2762 /**
2763  * ibmvscsis_service_wait_q() - Service Waiting Queue
2764  * @timer:      Pointer to timer which has expired
2765  *
2766  * This routine is called when the timer pops to service the waiting
2767  * queue. Elements on the queue have completed, their responses have been
2768  * copied to the client, but the client's response queue was full so
2769  * the queue message could not be sent. The routine grabs the proper locks
2770  * and calls send messages.
2771  *
2772  * EXECUTION ENVIRONMENT:
2773  *      called at interrupt level
2774  */
2775 static enum hrtimer_restart ibmvscsis_service_wait_q(struct hrtimer *timer)
2776 {
2777         struct timer_cb *p_timer = container_of(timer, struct timer_cb, timer);
2778         struct scsi_info *vscsi = container_of(p_timer, struct scsi_info,
2779                                                rsp_q_timer);
2780
2781         spin_lock_bh(&vscsi->intr_lock);
2782         p_timer->timer_pops += 1;
2783         p_timer->started = false;
2784         ibmvscsis_send_messages(vscsi);
2785         spin_unlock_bh(&vscsi->intr_lock);
2786
2787         return HRTIMER_NORESTART;
2788 }
2789
2790 static long ibmvscsis_alloctimer(struct scsi_info *vscsi)
2791 {
2792         struct timer_cb *p_timer;
2793
2794         p_timer = &vscsi->rsp_q_timer;
2795         hrtimer_init(&p_timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
2796
2797         p_timer->timer.function = ibmvscsis_service_wait_q;
2798         p_timer->started = false;
2799         p_timer->timer_pops = 0;
2800
2801         return ADAPT_SUCCESS;
2802 }
2803
2804 static void ibmvscsis_freetimer(struct scsi_info *vscsi)
2805 {
2806         struct timer_cb *p_timer;
2807
2808         p_timer = &vscsi->rsp_q_timer;
2809
2810         (void)hrtimer_cancel(&p_timer->timer);
2811
2812         p_timer->started = false;
2813         p_timer->timer_pops = 0;
2814 }
2815
2816 static irqreturn_t ibmvscsis_interrupt(int dummy, void *data)
2817 {
2818         struct scsi_info *vscsi = data;
2819
2820         vio_disable_interrupts(vscsi->dma_dev);
2821         tasklet_schedule(&vscsi->work_task);
2822
2823         return IRQ_HANDLED;
2824 }
2825
2826 /**
2827  * ibmvscsis_enable_change_state() - Set new state based on enabled status
2828  * @vscsi:      Pointer to our adapter structure
2829  *
2830  * This function determines our new state now that we are enabled.  This
2831  * may involve sending an Init Complete message to the client.
2832  *
2833  * Must be called with interrupt lock held.
2834  */
2835 static long ibmvscsis_enable_change_state(struct scsi_info *vscsi)
2836 {
2837         int bytes;
2838         long rc = ADAPT_SUCCESS;
2839
2840         bytes = vscsi->cmd_q.size * PAGE_SIZE;
2841         rc = h_reg_crq(vscsi->dds.unit_id, vscsi->cmd_q.crq_token, bytes);
2842         if (rc == H_CLOSED || rc == H_SUCCESS) {
2843                 vscsi->state = WAIT_CONNECTION;
2844                 rc = ibmvscsis_establish_new_q(vscsi);
2845         }
2846
2847         if (rc != ADAPT_SUCCESS) {
2848                 vscsi->state = ERR_DISCONNECTED;
2849                 vscsi->flags |= RESPONSE_Q_DOWN;
2850         }
2851
2852         return rc;
2853 }
2854
2855 /**
2856  * ibmvscsis_create_command_q() - Create Command Queue
2857  * @vscsi:      Pointer to our adapter structure
2858  * @num_cmds:   Currently unused.  In the future, may be used to determine
2859  *              the size of the CRQ.
2860  *
2861  * Allocates memory for command queue maps remote memory into an ioba
2862  * initializes the command response queue
2863  *
2864  * EXECUTION ENVIRONMENT:
2865  *      Process level only
2866  */
2867 static long ibmvscsis_create_command_q(struct scsi_info *vscsi, int num_cmds)
2868 {
2869         int pages;
2870         struct vio_dev *vdev = vscsi->dma_dev;
2871
2872         /* We might support multiple pages in the future, but just 1 for now */
2873         pages = 1;
2874
2875         vscsi->cmd_q.size = pages;
2876
2877         vscsi->cmd_q.base_addr =
2878                 (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
2879         if (!vscsi->cmd_q.base_addr)
2880                 return -ENOMEM;
2881
2882         vscsi->cmd_q.mask = ((uint)pages * CRQ_PER_PAGE) - 1;
2883
2884         vscsi->cmd_q.crq_token = dma_map_single(&vdev->dev,
2885                                                 vscsi->cmd_q.base_addr,
2886                                                 PAGE_SIZE, DMA_BIDIRECTIONAL);
2887         if (dma_mapping_error(&vdev->dev, vscsi->cmd_q.crq_token)) {
2888                 free_page((unsigned long)vscsi->cmd_q.base_addr);
2889                 return -ENOMEM;
2890         }
2891
2892         return 0;
2893 }
2894
2895 /**
2896  * ibmvscsis_destroy_command_q - Destroy Command Queue
2897  * @vscsi:      Pointer to our adapter structure
2898  *
2899  * Releases memory for command queue and unmaps mapped remote memory.
2900  *
2901  * EXECUTION ENVIRONMENT:
2902  *      Process level only
2903  */
2904 static void ibmvscsis_destroy_command_q(struct scsi_info *vscsi)
2905 {
2906         dma_unmap_single(&vscsi->dma_dev->dev, vscsi->cmd_q.crq_token,
2907                          PAGE_SIZE, DMA_BIDIRECTIONAL);
2908         free_page((unsigned long)vscsi->cmd_q.base_addr);
2909         vscsi->cmd_q.base_addr = NULL;
2910         vscsi->state = NO_QUEUE;
2911 }
2912
2913 static u8 ibmvscsis_fast_fail(struct scsi_info *vscsi,
2914                               struct ibmvscsis_cmd *cmd)
2915 {
2916         struct iu_entry *iue = cmd->iue;
2917         struct se_cmd *se_cmd = &cmd->se_cmd;
2918         struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
2919         struct scsi_sense_hdr sshdr;
2920         u8 rc = se_cmd->scsi_status;
2921
2922         if (vscsi->fast_fail && (READ_CMD(srp->cdb) || WRITE_CMD(srp->cdb)))
2923                 if (scsi_normalize_sense(se_cmd->sense_buffer,
2924                                          se_cmd->scsi_sense_length, &sshdr))
2925                         if (sshdr.sense_key == HARDWARE_ERROR &&
2926                             (se_cmd->residual_count == 0 ||
2927                              se_cmd->residual_count == se_cmd->data_length)) {
2928                                 rc = NO_SENSE;
2929                                 cmd->flags |= CMD_FAST_FAIL;
2930                         }
2931
2932         return rc;
2933 }
2934
2935 /**
2936  * srp_build_response() - Build an SRP response buffer
2937  * @vscsi:      Pointer to our adapter structure
2938  * @cmd:        Pointer to command for which to send the response
2939  * @len_p:      Where to return the length of the IU response sent.  This
2940  *              is needed to construct the CRQ response.
2941  *
2942  * Build the SRP response buffer and copy it to the client's memory space.
2943  */
2944 static long srp_build_response(struct scsi_info *vscsi,
2945                                struct ibmvscsis_cmd *cmd, uint *len_p)
2946 {
2947         struct iu_entry *iue = cmd->iue;
2948         struct se_cmd *se_cmd = &cmd->se_cmd;
2949         struct srp_rsp *rsp;
2950         uint len;
2951         u32 rsp_code;
2952         char *data;
2953         u32 *tsk_status;
2954         long rc = ADAPT_SUCCESS;
2955
2956         spin_lock_bh(&vscsi->intr_lock);
2957
2958         rsp = &vio_iu(iue)->srp.rsp;
2959         len = sizeof(*rsp);
2960         memset(rsp, 0, len);
2961         data = rsp->data;
2962
2963         rsp->opcode = SRP_RSP;
2964
2965         if (vscsi->credit > 0 && vscsi->state == SRP_PROCESSING)
2966                 rsp->req_lim_delta = cpu_to_be32(vscsi->credit);
2967         else
2968                 rsp->req_lim_delta = cpu_to_be32(1 + vscsi->credit);
2969         rsp->tag = cmd->rsp.tag;
2970         rsp->flags = 0;
2971
2972         if (cmd->type == SCSI_CDB) {
2973                 rsp->status = ibmvscsis_fast_fail(vscsi, cmd);
2974                 if (rsp->status) {
2975                         pr_debug("build_resp: cmd %p, scsi status %d\n", cmd,
2976                                  (int)rsp->status);
2977                         ibmvscsis_determine_resid(se_cmd, rsp);
2978                         if (se_cmd->scsi_sense_length && se_cmd->sense_buffer) {
2979                                 rsp->sense_data_len =
2980                                         cpu_to_be32(se_cmd->scsi_sense_length);
2981                                 rsp->flags |= SRP_RSP_FLAG_SNSVALID;
2982                                 len += se_cmd->scsi_sense_length;
2983                                 memcpy(data, se_cmd->sense_buffer,
2984                                        se_cmd->scsi_sense_length);
2985                         }
2986                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
2987                                 UCSOLNT_RESP_SHIFT;
2988                 } else if (cmd->flags & CMD_FAST_FAIL) {
2989                         pr_debug("build_resp: cmd %p, fast fail\n", cmd);
2990                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
2991                                 UCSOLNT_RESP_SHIFT;
2992                 } else {
2993                         rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
2994                                 SCSOLNT_RESP_SHIFT;
2995                 }
2996         } else {
2997                 /* this is task management */
2998                 rsp->status = 0;
2999                 rsp->resp_data_len = cpu_to_be32(4);
3000                 rsp->flags |= SRP_RSP_FLAG_RSPVALID;
3001
3002                 switch (se_cmd->se_tmr_req->response) {
3003                 case TMR_FUNCTION_COMPLETE:
3004                 case TMR_TASK_DOES_NOT_EXIST:
3005                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_COMPLETE;
3006                         rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
3007                                 SCSOLNT_RESP_SHIFT;
3008                         break;
3009                 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3010                 case TMR_LUN_DOES_NOT_EXIST:
3011                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_NOT_SUPPORTED;
3012                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
3013                                 UCSOLNT_RESP_SHIFT;
3014                         break;
3015                 case TMR_FUNCTION_FAILED:
3016                 case TMR_FUNCTION_REJECTED:
3017                 default:
3018                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_FAILED;
3019                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
3020                                 UCSOLNT_RESP_SHIFT;
3021                         break;
3022                 }
3023
3024                 tsk_status = (u32 *)data;
3025                 *tsk_status = cpu_to_be32(rsp_code);
3026                 data = (char *)(tsk_status + 1);
3027                 len += 4;
3028         }
3029
3030         dma_wmb();
3031         rc = h_copy_rdma(len, vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
3032                          vscsi->dds.window[REMOTE].liobn,
3033                          be64_to_cpu(iue->remote_token));
3034
3035         switch (rc) {
3036         case H_SUCCESS:
3037                 vscsi->credit = 0;
3038                 *len_p = len;
3039                 break;
3040         case H_PERMISSION:
3041                 if (connection_broken(vscsi))
3042                         vscsi->flags |= RESPONSE_Q_DOWN | CLIENT_FAILED;
3043
3044                 dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld, flags 0x%x, state 0x%hx\n",
3045                         rc, vscsi->flags, vscsi->state);
3046                 break;
3047         case H_SOURCE_PARM:
3048         case H_DEST_PARM:
3049         default:
3050                 dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld\n",
3051                         rc);
3052                 break;
3053         }
3054
3055         spin_unlock_bh(&vscsi->intr_lock);
3056
3057         return rc;
3058 }
3059
3060 static int ibmvscsis_rdma(struct ibmvscsis_cmd *cmd, struct scatterlist *sg,
3061                           int nsg, struct srp_direct_buf *md, int nmd,
3062                           enum dma_data_direction dir, unsigned int bytes)
3063 {
3064         struct iu_entry *iue = cmd->iue;
3065         struct srp_target *target = iue->target;
3066         struct scsi_info *vscsi = target->ldata;
3067         struct scatterlist *sgp;
3068         dma_addr_t client_ioba, server_ioba;
3069         ulong buf_len;
3070         ulong client_len, server_len;
3071         int md_idx;
3072         long tx_len;
3073         long rc = 0;
3074
3075         if (bytes == 0)
3076                 return 0;
3077
3078         sgp = sg;
3079         client_len = 0;
3080         server_len = 0;
3081         md_idx = 0;
3082         tx_len = bytes;
3083
3084         do {
3085                 if (client_len == 0) {
3086                         if (md_idx >= nmd) {
3087                                 dev_err(&vscsi->dev, "rdma: ran out of client memory descriptors\n");
3088                                 rc = -EIO;
3089                                 break;
3090                         }
3091                         client_ioba = be64_to_cpu(md[md_idx].va);
3092                         client_len = be32_to_cpu(md[md_idx].len);
3093                 }
3094                 if (server_len == 0) {
3095                         if (!sgp) {
3096                                 dev_err(&vscsi->dev, "rdma: ran out of scatter/gather list\n");
3097                                 rc = -EIO;
3098                                 break;
3099                         }
3100                         server_ioba = sg_dma_address(sgp);
3101                         server_len = sg_dma_len(sgp);
3102                 }
3103
3104                 buf_len = tx_len;
3105
3106                 if (buf_len > client_len)
3107                         buf_len = client_len;
3108
3109                 if (buf_len > server_len)
3110                         buf_len = server_len;
3111
3112                 if (buf_len > max_vdma_size)
3113                         buf_len = max_vdma_size;
3114
3115                 if (dir == DMA_TO_DEVICE) {
3116                         /* read from client */
3117                         rc = h_copy_rdma(buf_len,
3118                                          vscsi->dds.window[REMOTE].liobn,
3119                                          client_ioba,
3120                                          vscsi->dds.window[LOCAL].liobn,
3121                                          server_ioba);
3122                 } else {
3123                         /* The h_copy_rdma will cause phyp, running in another
3124                          * partition, to read memory, so we need to make sure
3125                          * the data has been written out, hence these syncs.
3126                          */
3127                         /* ensure that everything is in memory */
3128                         isync();
3129                         /* ensure that memory has been made visible */
3130                         dma_wmb();
3131                         rc = h_copy_rdma(buf_len,
3132                                          vscsi->dds.window[LOCAL].liobn,
3133                                          server_ioba,
3134                                          vscsi->dds.window[REMOTE].liobn,
3135                                          client_ioba);
3136                 }
3137                 switch (rc) {
3138                 case H_SUCCESS:
3139                         break;
3140                 case H_PERMISSION:
3141                 case H_SOURCE_PARM:
3142                 case H_DEST_PARM:
3143                         if (connection_broken(vscsi)) {
3144                                 spin_lock_bh(&vscsi->intr_lock);
3145                                 vscsi->flags |=
3146                                         (RESPONSE_Q_DOWN | CLIENT_FAILED);
3147                                 spin_unlock_bh(&vscsi->intr_lock);
3148                         }
3149                         dev_err(&vscsi->dev, "rdma: h_copy_rdma failed, rc %ld\n",
3150                                 rc);
3151                         break;
3152
3153                 default:
3154                         dev_err(&vscsi->dev, "rdma: unknown error %ld from h_copy_rdma\n",
3155                                 rc);
3156                         break;
3157                 }
3158
3159                 if (!rc) {
3160                         tx_len -= buf_len;
3161                         if (tx_len) {
3162                                 client_len -= buf_len;
3163                                 if (client_len == 0)
3164                                         md_idx++;
3165                                 else
3166                                         client_ioba += buf_len;
3167
3168                                 server_len -= buf_len;
3169                                 if (server_len == 0)
3170                                         sgp = sg_next(sgp);
3171                                 else
3172                                         server_ioba += buf_len;
3173                         } else {
3174                                 break;
3175                         }
3176                 }
3177         } while (!rc);
3178
3179         return rc;
3180 }
3181
3182 /**
3183  * ibmvscsis_handle_crq() - Handle CRQ
3184  * @data:       Pointer to our adapter structure
3185  *
3186  * Read the command elements from the command queue and copy the payloads
3187  * associated with the command elements to local memory and execute the
3188  * SRP requests.
3189  *
3190  * Note: this is an edge triggered interrupt. It can not be shared.
3191  */
3192 static void ibmvscsis_handle_crq(unsigned long data)
3193 {
3194         struct scsi_info *vscsi = (struct scsi_info *)data;
3195         struct viosrp_crq *crq;
3196         long rc;
3197         bool ack = true;
3198         volatile u8 valid;
3199
3200         spin_lock_bh(&vscsi->intr_lock);
3201
3202         pr_debug("got interrupt\n");
3203
3204         /*
3205          * if we are in a path where we are waiting for all pending commands
3206          * to complete because we received a transport event and anything in
3207          * the command queue is for a new connection, do nothing
3208          */
3209         if (TARGET_STOP(vscsi)) {
3210                 vio_enable_interrupts(vscsi->dma_dev);
3211
3212                 pr_debug("handle_crq, don't process: flags 0x%x, state 0x%hx\n",
3213                          vscsi->flags, vscsi->state);
3214                 spin_unlock_bh(&vscsi->intr_lock);
3215                 return;
3216         }
3217
3218         rc = vscsi->flags & SCHEDULE_DISCONNECT;
3219         crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
3220         valid = crq->valid;
3221         dma_rmb();
3222
3223         while (valid) {
3224                 /*
3225                  * These are edege triggered interrupts. After dropping out of
3226                  * the while loop, the code must check for work since an
3227                  * interrupt could be lost, and an elment be left on the queue,
3228                  * hence the label.
3229                  */
3230 cmd_work:
3231                 vscsi->cmd_q.index =
3232                         (vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
3233
3234                 if (!rc) {
3235                         rc = ibmvscsis_parse_command(vscsi, crq);
3236                 } else {
3237                         if ((uint)crq->valid == VALID_TRANS_EVENT) {
3238                                 /*
3239                                  * must service the transport layer events even
3240                                  * in an error state, dont break out until all
3241                                  * the consecutive transport events have been
3242                                  * processed
3243                                  */
3244                                 rc = ibmvscsis_trans_event(vscsi, crq);
3245                         } else if (vscsi->flags & TRANS_EVENT) {
3246                                 /*
3247                                  * if a transport event has occurred leave
3248                                  * everything but transport events on the queue
3249                                  *
3250                                  * need to decrement the queue index so we can
3251                                  * look at the element again
3252                                  */
3253                                 if (vscsi->cmd_q.index)
3254                                         vscsi->cmd_q.index -= 1;
3255                                 else
3256                                         /*
3257                                          * index is at 0 it just wrapped.
3258                                          * have it index last element in q
3259                                          */
3260                                         vscsi->cmd_q.index = vscsi->cmd_q.mask;
3261                                 break;
3262                         }
3263                 }
3264
3265                 crq->valid = INVALIDATE_CMD_RESP_EL;
3266
3267                 crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
3268                 valid = crq->valid;
3269                 dma_rmb();
3270         }
3271
3272         if (!rc) {
3273                 if (ack) {
3274                         vio_enable_interrupts(vscsi->dma_dev);
3275                         ack = false;
3276                         pr_debug("handle_crq, reenabling interrupts\n");
3277                 }
3278                 valid = crq->valid;
3279                 dma_rmb();
3280                 if (valid)
3281                         goto cmd_work;
3282         } else {
3283                 pr_debug("handle_crq, error: flags 0x%x, state 0x%hx, crq index 0x%x\n",
3284                          vscsi->flags, vscsi->state, vscsi->cmd_q.index);
3285         }
3286
3287         pr_debug("Leaving handle_crq: schedule_q empty %d, flags 0x%x, state 0x%hx\n",
3288                  (int)list_empty(&vscsi->schedule_q), vscsi->flags,
3289                  vscsi->state);
3290
3291         spin_unlock_bh(&vscsi->intr_lock);
3292 }
3293
3294 static int ibmvscsis_probe(struct vio_dev *vdev,
3295                            const struct vio_device_id *id)
3296 {
3297         struct scsi_info *vscsi;
3298         int rc = 0;
3299         long hrc = 0;
3300         char wq_name[24];
3301
3302         vscsi = kzalloc(sizeof(*vscsi), GFP_KERNEL);
3303         if (!vscsi) {
3304                 rc = -ENOMEM;
3305                 pr_err("probe: allocation of adapter failed\n");
3306                 return rc;
3307         }
3308
3309         vscsi->dma_dev = vdev;
3310         vscsi->dev = vdev->dev;
3311         INIT_LIST_HEAD(&vscsi->schedule_q);
3312         INIT_LIST_HEAD(&vscsi->waiting_rsp);
3313         INIT_LIST_HEAD(&vscsi->active_q);
3314
3315         snprintf(vscsi->tport.tport_name, IBMVSCSIS_NAMELEN, "%s",
3316                  dev_name(&vdev->dev));
3317
3318         pr_debug("probe tport_name: %s\n", vscsi->tport.tport_name);
3319
3320         rc = read_dma_window(vscsi);
3321         if (rc)
3322                 goto free_adapter;
3323         pr_debug("Probe: liobn 0x%x, riobn 0x%x\n",
3324                  vscsi->dds.window[LOCAL].liobn,
3325                  vscsi->dds.window[REMOTE].liobn);
3326
3327         strcpy(vscsi->eye, "VSCSI ");
3328         strncat(vscsi->eye, vdev->name, MAX_EYE);
3329
3330         vscsi->dds.unit_id = vdev->unit_address;
3331         strncpy(vscsi->dds.partition_name, partition_name,
3332                 sizeof(vscsi->dds.partition_name));
3333         vscsi->dds.partition_num = partition_number;
3334
3335         spin_lock_bh(&ibmvscsis_dev_lock);
3336         list_add_tail(&vscsi->list, &ibmvscsis_dev_list);
3337         spin_unlock_bh(&ibmvscsis_dev_lock);
3338
3339         /*
3340          * TBD: How do we determine # of cmds to request?  Do we know how
3341          * many "children" we have?
3342          */
3343         vscsi->request_limit = INITIAL_SRP_LIMIT;
3344         rc = srp_target_alloc(&vscsi->target, &vdev->dev, vscsi->request_limit,
3345                               SRP_MAX_IU_LEN);
3346         if (rc)
3347                 goto rem_list;
3348
3349         vscsi->target.ldata = vscsi;
3350
3351         rc = ibmvscsis_alloc_cmds(vscsi, vscsi->request_limit);
3352         if (rc) {
3353                 dev_err(&vscsi->dev, "alloc_cmds failed, rc %d, num %d\n",
3354                         rc, vscsi->request_limit);
3355                 goto free_target;
3356         }
3357
3358         /*
3359          * Note: the lock is used in freeing timers, so must initialize
3360          * first so that ordering in case of error is correct.
3361          */
3362         spin_lock_init(&vscsi->intr_lock);
3363
3364         rc = ibmvscsis_alloctimer(vscsi);
3365         if (rc) {
3366                 dev_err(&vscsi->dev, "probe: alloctimer failed, rc %d\n", rc);
3367                 goto free_cmds;
3368         }
3369
3370         rc = ibmvscsis_create_command_q(vscsi, 256);
3371         if (rc) {
3372                 dev_err(&vscsi->dev, "probe: create_command_q failed, rc %d\n",
3373                         rc);
3374                 goto free_timer;
3375         }
3376
3377         vscsi->map_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
3378         if (!vscsi->map_buf) {
3379                 rc = -ENOMEM;
3380                 dev_err(&vscsi->dev, "probe: allocating cmd buffer failed\n");
3381                 goto destroy_queue;
3382         }
3383
3384         vscsi->map_ioba = dma_map_single(&vdev->dev, vscsi->map_buf, PAGE_SIZE,
3385                                          DMA_BIDIRECTIONAL);
3386         if (dma_mapping_error(&vdev->dev, vscsi->map_ioba)) {
3387                 rc = -ENOMEM;
3388                 dev_err(&vscsi->dev, "probe: error mapping command buffer\n");
3389                 goto free_buf;
3390         }
3391
3392         hrc = h_vioctl(vscsi->dds.unit_id, H_GET_PARTNER_INFO,
3393                        (u64)vscsi->map_ioba | ((u64)PAGE_SIZE << 32), 0, 0, 0,
3394                        0);
3395         if (hrc == H_SUCCESS)
3396                 vscsi->client_data.partition_number =
3397                         be64_to_cpu(*(u64 *)vscsi->map_buf);
3398         /*
3399          * We expect the VIOCTL to fail if we're configured as "any
3400          * client can connect" and the client isn't activated yet.
3401          * We'll make the call again when he sends an init msg.
3402          */
3403         pr_debug("probe hrc %ld, client partition num %d\n",
3404                  hrc, vscsi->client_data.partition_number);
3405
3406         tasklet_init(&vscsi->work_task, ibmvscsis_handle_crq,
3407                      (unsigned long)vscsi);
3408
3409         init_completion(&vscsi->wait_idle);
3410         init_completion(&vscsi->unconfig);
3411
3412         snprintf(wq_name, 24, "ibmvscsis%s", dev_name(&vdev->dev));
3413         vscsi->work_q = create_workqueue(wq_name);
3414         if (!vscsi->work_q) {
3415                 rc = -ENOMEM;
3416                 dev_err(&vscsi->dev, "create_workqueue failed\n");
3417                 goto unmap_buf;
3418         }
3419
3420         rc = request_irq(vdev->irq, ibmvscsis_interrupt, 0, "ibmvscsis", vscsi);
3421         if (rc) {
3422                 rc = -EPERM;
3423                 dev_err(&vscsi->dev, "probe: request_irq failed, rc %d\n", rc);
3424                 goto destroy_WQ;
3425         }
3426
3427         vscsi->state = WAIT_ENABLED;
3428
3429         dev_set_drvdata(&vdev->dev, vscsi);
3430
3431         return 0;
3432
3433 destroy_WQ:
3434         destroy_workqueue(vscsi->work_q);
3435 unmap_buf:
3436         dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
3437                          DMA_BIDIRECTIONAL);
3438 free_buf:
3439         kfree(vscsi->map_buf);
3440 destroy_queue:
3441         tasklet_kill(&vscsi->work_task);
3442         ibmvscsis_unregister_command_q(vscsi);
3443         ibmvscsis_destroy_command_q(vscsi);
3444 free_timer:
3445         ibmvscsis_freetimer(vscsi);
3446 free_cmds:
3447         ibmvscsis_free_cmds(vscsi);
3448 free_target:
3449         srp_target_free(&vscsi->target);
3450 rem_list:
3451         spin_lock_bh(&ibmvscsis_dev_lock);
3452         list_del(&vscsi->list);
3453         spin_unlock_bh(&ibmvscsis_dev_lock);
3454 free_adapter:
3455         kfree(vscsi);
3456
3457         return rc;
3458 }
3459
3460 static int ibmvscsis_remove(struct vio_dev *vdev)
3461 {
3462         struct scsi_info *vscsi = dev_get_drvdata(&vdev->dev);
3463
3464         pr_debug("remove (%s)\n", dev_name(&vscsi->dma_dev->dev));
3465
3466         spin_lock_bh(&vscsi->intr_lock);
3467         ibmvscsis_post_disconnect(vscsi, UNCONFIGURING, 0);
3468         vscsi->flags |= CFG_SLEEPING;
3469         spin_unlock_bh(&vscsi->intr_lock);
3470         wait_for_completion(&vscsi->unconfig);
3471
3472         vio_disable_interrupts(vdev);
3473         free_irq(vdev->irq, vscsi);
3474         destroy_workqueue(vscsi->work_q);
3475         dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
3476                          DMA_BIDIRECTIONAL);
3477         kfree(vscsi->map_buf);
3478         tasklet_kill(&vscsi->work_task);
3479         ibmvscsis_destroy_command_q(vscsi);
3480         ibmvscsis_freetimer(vscsi);
3481         ibmvscsis_free_cmds(vscsi);
3482         srp_target_free(&vscsi->target);
3483         spin_lock_bh(&ibmvscsis_dev_lock);
3484         list_del(&vscsi->list);
3485         spin_unlock_bh(&ibmvscsis_dev_lock);
3486         kfree(vscsi);
3487
3488         return 0;
3489 }
3490
3491 static ssize_t system_id_show(struct device *dev,
3492                               struct device_attribute *attr, char *buf)
3493 {
3494         return snprintf(buf, PAGE_SIZE, "%s\n", system_id);
3495 }
3496
3497 static ssize_t partition_number_show(struct device *dev,
3498                                      struct device_attribute *attr, char *buf)
3499 {
3500         return snprintf(buf, PAGE_SIZE, "%x\n", partition_number);
3501 }
3502
3503 static ssize_t unit_address_show(struct device *dev,
3504                                  struct device_attribute *attr, char *buf)
3505 {
3506         struct scsi_info *vscsi = container_of(dev, struct scsi_info, dev);
3507
3508         return snprintf(buf, PAGE_SIZE, "%x\n", vscsi->dma_dev->unit_address);
3509 }
3510
3511 static int ibmvscsis_get_system_info(void)
3512 {
3513         struct device_node *rootdn, *vdevdn;
3514         const char *id, *model, *name;
3515         const uint *num;
3516
3517         rootdn = of_find_node_by_path("/");
3518         if (!rootdn)
3519                 return -ENOENT;
3520
3521         model = of_get_property(rootdn, "model", NULL);
3522         id = of_get_property(rootdn, "system-id", NULL);
3523         if (model && id)
3524                 snprintf(system_id, sizeof(system_id), "%s-%s", model, id);
3525
3526         name = of_get_property(rootdn, "ibm,partition-name", NULL);
3527         if (name)
3528                 strncpy(partition_name, name, sizeof(partition_name));
3529
3530         num = of_get_property(rootdn, "ibm,partition-no", NULL);
3531         if (num)
3532                 partition_number = of_read_number(num, 1);
3533
3534         of_node_put(rootdn);
3535
3536         vdevdn = of_find_node_by_path("/vdevice");
3537         if (vdevdn) {
3538                 const uint *mvds;
3539
3540                 mvds = of_get_property(vdevdn, "ibm,max-virtual-dma-size",
3541                                        NULL);
3542                 if (mvds)
3543                         max_vdma_size = *mvds;
3544                 of_node_put(vdevdn);
3545         }
3546
3547         return 0;
3548 }
3549
3550 static char *ibmvscsis_get_fabric_name(void)
3551 {
3552         return "ibmvscsis";
3553 }
3554
3555 static char *ibmvscsis_get_fabric_wwn(struct se_portal_group *se_tpg)
3556 {
3557         struct ibmvscsis_tport *tport =
3558                 container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
3559
3560         return tport->tport_name;
3561 }
3562
3563 static u16 ibmvscsis_get_tag(struct se_portal_group *se_tpg)
3564 {
3565         struct ibmvscsis_tport *tport =
3566                 container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
3567
3568         return tport->tport_tpgt;
3569 }
3570
3571 static u32 ibmvscsis_get_default_depth(struct se_portal_group *se_tpg)
3572 {
3573         return 1;
3574 }
3575
3576 static int ibmvscsis_check_true(struct se_portal_group *se_tpg)
3577 {
3578         return 1;
3579 }
3580
3581 static int ibmvscsis_check_false(struct se_portal_group *se_tpg)
3582 {
3583         return 0;
3584 }
3585
3586 static u32 ibmvscsis_tpg_get_inst_index(struct se_portal_group *se_tpg)
3587 {
3588         return 1;
3589 }
3590
3591 static int ibmvscsis_check_stop_free(struct se_cmd *se_cmd)
3592 {
3593         return target_put_sess_cmd(se_cmd);
3594 }
3595
3596 static void ibmvscsis_release_cmd(struct se_cmd *se_cmd)
3597 {
3598         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3599                                                  se_cmd);
3600         struct scsi_info *vscsi = cmd->adapter;
3601
3602         spin_lock_bh(&vscsi->intr_lock);
3603         /* Remove from active_q */
3604         list_move_tail(&cmd->list, &vscsi->waiting_rsp);
3605         ibmvscsis_send_messages(vscsi);
3606         spin_unlock_bh(&vscsi->intr_lock);
3607 }
3608
3609 static u32 ibmvscsis_sess_get_index(struct se_session *se_sess)
3610 {
3611         return 0;
3612 }
3613
3614 static int ibmvscsis_write_pending(struct se_cmd *se_cmd)
3615 {
3616         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3617                                                  se_cmd);
3618         struct scsi_info *vscsi = cmd->adapter;
3619         struct iu_entry *iue = cmd->iue;
3620         int rc;
3621
3622         /*
3623          * If CLIENT_FAILED OR RESPONSE_Q_DOWN, then just return success
3624          * since LIO can't do anything about it, and we dont want to
3625          * attempt an srp_transfer_data.
3626          */
3627         if ((vscsi->flags & (CLIENT_FAILED | RESPONSE_Q_DOWN))) {
3628                 pr_err("write_pending failed since: %d\n", vscsi->flags);
3629                 return 0;
3630         }
3631
3632         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma,
3633                                1, 1);
3634         if (rc) {
3635                 pr_err("srp_transfer_data() failed: %d\n", rc);
3636                 return -EIO;
3637         }
3638         /*
3639          * We now tell TCM to add this WRITE CDB directly into the TCM storage
3640          * object execution queue.
3641          */
3642         target_execute_cmd(se_cmd);
3643         return 0;
3644 }
3645
3646 static int ibmvscsis_write_pending_status(struct se_cmd *se_cmd)
3647 {
3648         return 0;
3649 }
3650
3651 static void ibmvscsis_set_default_node_attrs(struct se_node_acl *nacl)
3652 {
3653 }
3654
3655 static int ibmvscsis_get_cmd_state(struct se_cmd *se_cmd)
3656 {
3657         return 0;
3658 }
3659
3660 static int ibmvscsis_queue_data_in(struct se_cmd *se_cmd)
3661 {
3662         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3663                                                  se_cmd);
3664         struct iu_entry *iue = cmd->iue;
3665         struct scsi_info *vscsi = cmd->adapter;
3666         char *sd;
3667         uint len = 0;
3668         int rc;
3669
3670         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma, 1,
3671                                1);
3672         if (rc) {
3673                 pr_err("srp_transfer_data failed: %d\n", rc);
3674                 sd = se_cmd->sense_buffer;
3675                 se_cmd->scsi_sense_length = 18;
3676                 memset(se_cmd->sense_buffer, 0, se_cmd->scsi_sense_length);
3677                 /* Logical Unit Communication Time-out asc/ascq = 0x0801 */
3678                 scsi_build_sense_buffer(0, se_cmd->sense_buffer, MEDIUM_ERROR,
3679                                         0x08, 0x01);
3680         }
3681
3682         srp_build_response(vscsi, cmd, &len);
3683         cmd->rsp.format = SRP_FORMAT;
3684         cmd->rsp.len = len;
3685
3686         return 0;
3687 }
3688
3689 static int ibmvscsis_queue_status(struct se_cmd *se_cmd)
3690 {
3691         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3692                                                  se_cmd);
3693         struct scsi_info *vscsi = cmd->adapter;
3694         uint len;
3695
3696         pr_debug("queue_status %p\n", se_cmd);
3697
3698         srp_build_response(vscsi, cmd, &len);
3699         cmd->rsp.format = SRP_FORMAT;
3700         cmd->rsp.len = len;
3701
3702         return 0;
3703 }
3704
3705 static void ibmvscsis_queue_tm_rsp(struct se_cmd *se_cmd)
3706 {
3707         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3708                                                  se_cmd);
3709         struct scsi_info *vscsi = cmd->adapter;
3710         struct ibmvscsis_cmd *cmd_itr;
3711         struct iu_entry *iue = iue = cmd->iue;
3712         struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
3713         u64 tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
3714         uint len;
3715
3716         pr_debug("queue_tm_rsp %p, status %d\n",
3717                  se_cmd, (int)se_cmd->se_tmr_req->response);
3718
3719         if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK &&
3720             cmd->se_cmd.se_tmr_req->response == TMR_TASK_DOES_NOT_EXIST) {
3721                 spin_lock_bh(&vscsi->intr_lock);
3722                 list_for_each_entry(cmd_itr, &vscsi->active_q, list) {
3723                         if (tag_to_abort == cmd_itr->se_cmd.tag) {
3724                                 cmd_itr->abort_cmd = cmd;
3725                                 cmd->flags |= DELAY_SEND;
3726                                 break;
3727                         }
3728                 }
3729                 spin_unlock_bh(&vscsi->intr_lock);
3730         }
3731
3732         srp_build_response(vscsi, cmd, &len);
3733         cmd->rsp.format = SRP_FORMAT;
3734         cmd->rsp.len = len;
3735 }
3736
3737 static void ibmvscsis_aborted_task(struct se_cmd *se_cmd)
3738 {
3739         pr_debug("ibmvscsis_aborted_task %p task_tag: %llu\n",
3740                  se_cmd, se_cmd->tag);
3741 }
3742
3743 static struct se_wwn *ibmvscsis_make_tport(struct target_fabric_configfs *tf,
3744                                            struct config_group *group,
3745                                            const char *name)
3746 {
3747         struct ibmvscsis_tport *tport;
3748
3749         tport = ibmvscsis_lookup_port(name);
3750         if (tport) {
3751                 tport->tport_proto_id = SCSI_PROTOCOL_SRP;
3752                 pr_debug("make_tport(%s), pointer:%p, tport_id:%x\n",
3753                          name, tport, tport->tport_proto_id);
3754                 return &tport->tport_wwn;
3755         }
3756
3757         return ERR_PTR(-EINVAL);
3758 }
3759
3760 static void ibmvscsis_drop_tport(struct se_wwn *wwn)
3761 {
3762         struct ibmvscsis_tport *tport = container_of(wwn,
3763                                                      struct ibmvscsis_tport,
3764                                                      tport_wwn);
3765
3766         pr_debug("drop_tport(%s)\n",
3767                  config_item_name(&tport->tport_wwn.wwn_group.cg_item));
3768 }
3769
3770 static struct se_portal_group *ibmvscsis_make_tpg(struct se_wwn *wwn,
3771                                                   struct config_group *group,
3772                                                   const char *name)
3773 {
3774         struct ibmvscsis_tport *tport =
3775                 container_of(wwn, struct ibmvscsis_tport, tport_wwn);
3776         int rc;
3777
3778         tport->releasing = false;
3779
3780         rc = core_tpg_register(&tport->tport_wwn, &tport->se_tpg,
3781                                tport->tport_proto_id);
3782         if (rc)
3783                 return ERR_PTR(rc);
3784
3785         return &tport->se_tpg;
3786 }
3787
3788 static void ibmvscsis_drop_tpg(struct se_portal_group *se_tpg)
3789 {
3790         struct ibmvscsis_tport *tport = container_of(se_tpg,
3791                                                      struct ibmvscsis_tport,
3792                                                      se_tpg);
3793
3794         tport->releasing = true;
3795         tport->enabled = false;
3796
3797         /*
3798          * Release the virtual I_T Nexus for this ibmvscsis TPG
3799          */
3800         ibmvscsis_drop_nexus(tport);
3801         /*
3802          * Deregister the se_tpg from TCM..
3803          */
3804         core_tpg_deregister(se_tpg);
3805 }
3806
3807 static ssize_t ibmvscsis_wwn_version_show(struct config_item *item,
3808                                           char *page)
3809 {
3810         return scnprintf(page, PAGE_SIZE, "%s\n", IBMVSCSIS_VERSION);
3811 }
3812 CONFIGFS_ATTR_RO(ibmvscsis_wwn_, version);
3813
3814 static struct configfs_attribute *ibmvscsis_wwn_attrs[] = {
3815         &ibmvscsis_wwn_attr_version,
3816         NULL,
3817 };
3818
3819 static ssize_t ibmvscsis_tpg_enable_show(struct config_item *item,
3820                                          char *page)
3821 {
3822         struct se_portal_group *se_tpg = to_tpg(item);
3823         struct ibmvscsis_tport *tport = container_of(se_tpg,
3824                                                      struct ibmvscsis_tport,
3825                                                      se_tpg);
3826
3827         return snprintf(page, PAGE_SIZE, "%d\n", (tport->enabled) ? 1 : 0);
3828 }
3829
3830 static ssize_t ibmvscsis_tpg_enable_store(struct config_item *item,
3831                                           const char *page, size_t count)
3832 {
3833         struct se_portal_group *se_tpg = to_tpg(item);
3834         struct ibmvscsis_tport *tport = container_of(se_tpg,
3835                                                      struct ibmvscsis_tport,
3836                                                      se_tpg);
3837         struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
3838         unsigned long tmp;
3839         int rc;
3840         long lrc;
3841
3842         rc = kstrtoul(page, 0, &tmp);
3843         if (rc < 0) {
3844                 pr_err("Unable to extract srpt_tpg_store_enable\n");
3845                 return -EINVAL;
3846         }
3847
3848         if ((tmp != 0) && (tmp != 1)) {
3849                 pr_err("Illegal value for srpt_tpg_store_enable\n");
3850                 return -EINVAL;
3851         }
3852
3853         if (tmp) {
3854                 spin_lock_bh(&vscsi->intr_lock);
3855                 tport->enabled = true;
3856                 lrc = ibmvscsis_enable_change_state(vscsi);
3857                 if (lrc)
3858                         pr_err("enable_change_state failed, rc %ld state %d\n",
3859                                lrc, vscsi->state);
3860                 spin_unlock_bh(&vscsi->intr_lock);
3861         } else {
3862                 spin_lock_bh(&vscsi->intr_lock);
3863                 tport->enabled = false;
3864                 /* This simulates the server going down */
3865                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
3866                 spin_unlock_bh(&vscsi->intr_lock);
3867         }
3868
3869         pr_debug("tpg_enable_store, tmp %ld, state %d\n", tmp, vscsi->state);
3870
3871         return count;
3872 }
3873 CONFIGFS_ATTR(ibmvscsis_tpg_, enable);
3874
3875 static struct configfs_attribute *ibmvscsis_tpg_attrs[] = {
3876         &ibmvscsis_tpg_attr_enable,
3877         NULL,
3878 };
3879
3880 static const struct target_core_fabric_ops ibmvscsis_ops = {
3881         .module                         = THIS_MODULE,
3882         .name                           = "ibmvscsis",
3883         .max_data_sg_nents              = MAX_TXU / PAGE_SIZE,
3884         .get_fabric_name                = ibmvscsis_get_fabric_name,
3885         .tpg_get_wwn                    = ibmvscsis_get_fabric_wwn,
3886         .tpg_get_tag                    = ibmvscsis_get_tag,
3887         .tpg_get_default_depth          = ibmvscsis_get_default_depth,
3888         .tpg_check_demo_mode            = ibmvscsis_check_true,
3889         .tpg_check_demo_mode_cache      = ibmvscsis_check_true,
3890         .tpg_check_demo_mode_write_protect = ibmvscsis_check_false,
3891         .tpg_check_prod_mode_write_protect = ibmvscsis_check_false,
3892         .tpg_get_inst_index             = ibmvscsis_tpg_get_inst_index,
3893         .check_stop_free                = ibmvscsis_check_stop_free,
3894         .release_cmd                    = ibmvscsis_release_cmd,
3895         .sess_get_index                 = ibmvscsis_sess_get_index,
3896         .write_pending                  = ibmvscsis_write_pending,
3897         .write_pending_status           = ibmvscsis_write_pending_status,
3898         .set_default_node_attributes    = ibmvscsis_set_default_node_attrs,
3899         .get_cmd_state                  = ibmvscsis_get_cmd_state,
3900         .queue_data_in                  = ibmvscsis_queue_data_in,
3901         .queue_status                   = ibmvscsis_queue_status,
3902         .queue_tm_rsp                   = ibmvscsis_queue_tm_rsp,
3903         .aborted_task                   = ibmvscsis_aborted_task,
3904         /*
3905          * Setup function pointers for logic in target_core_fabric_configfs.c
3906          */
3907         .fabric_make_wwn                = ibmvscsis_make_tport,
3908         .fabric_drop_wwn                = ibmvscsis_drop_tport,
3909         .fabric_make_tpg                = ibmvscsis_make_tpg,
3910         .fabric_drop_tpg                = ibmvscsis_drop_tpg,
3911
3912         .tfc_wwn_attrs                  = ibmvscsis_wwn_attrs,
3913         .tfc_tpg_base_attrs             = ibmvscsis_tpg_attrs,
3914 };
3915
3916 static void ibmvscsis_dev_release(struct device *dev) {};
3917
3918 static struct class_attribute ibmvscsis_class_attrs[] = {
3919         __ATTR_NULL,
3920 };
3921
3922 static struct device_attribute dev_attr_system_id =
3923         __ATTR(system_id, S_IRUGO, system_id_show, NULL);
3924
3925 static struct device_attribute dev_attr_partition_number =
3926         __ATTR(partition_number, S_IRUGO, partition_number_show, NULL);
3927
3928 static struct device_attribute dev_attr_unit_address =
3929         __ATTR(unit_address, S_IRUGO, unit_address_show, NULL);
3930
3931 static struct attribute *ibmvscsis_dev_attrs[] = {
3932         &dev_attr_system_id.attr,
3933         &dev_attr_partition_number.attr,
3934         &dev_attr_unit_address.attr,
3935 };
3936 ATTRIBUTE_GROUPS(ibmvscsis_dev);
3937
3938 static struct class ibmvscsis_class = {
3939         .name           = "ibmvscsis",
3940         .dev_release    = ibmvscsis_dev_release,
3941         .class_attrs    = ibmvscsis_class_attrs,
3942         .dev_groups     = ibmvscsis_dev_groups,
3943 };
3944
3945 static struct vio_device_id ibmvscsis_device_table[] = {
3946         { "v-scsi-host", "IBM,v-scsi-host" },
3947         { "", "" }
3948 };
3949 MODULE_DEVICE_TABLE(vio, ibmvscsis_device_table);
3950
3951 static struct vio_driver ibmvscsis_driver = {
3952         .name = "ibmvscsis",
3953         .id_table = ibmvscsis_device_table,
3954         .probe = ibmvscsis_probe,
3955         .remove = ibmvscsis_remove,
3956 };
3957
3958 /*
3959  * ibmvscsis_init() - Kernel Module initialization
3960  *
3961  * Note: vio_register_driver() registers callback functions, and at least one
3962  * of those callback functions calls TCM - Linux IO Target Subsystem, thus
3963  * the SCSI Target template must be registered before vio_register_driver()
3964  * is called.
3965  */
3966 static int __init ibmvscsis_init(void)
3967 {
3968         int rc = 0;
3969
3970         rc = ibmvscsis_get_system_info();
3971         if (rc) {
3972                 pr_err("rc %d from get_system_info\n", rc);
3973                 goto out;
3974         }
3975
3976         rc = class_register(&ibmvscsis_class);
3977         if (rc) {
3978                 pr_err("failed class register\n");
3979                 goto out;
3980         }
3981
3982         rc = target_register_template(&ibmvscsis_ops);
3983         if (rc) {
3984                 pr_err("rc %d from target_register_template\n", rc);
3985                 goto unregister_class;
3986         }
3987
3988         rc = vio_register_driver(&ibmvscsis_driver);
3989         if (rc) {
3990                 pr_err("rc %d from vio_register_driver\n", rc);
3991                 goto unregister_target;
3992         }
3993
3994         return 0;
3995
3996 unregister_target:
3997         target_unregister_template(&ibmvscsis_ops);
3998 unregister_class:
3999         class_unregister(&ibmvscsis_class);
4000 out:
4001         return rc;
4002 }
4003
4004 static void __exit ibmvscsis_exit(void)
4005 {
4006         pr_info("Unregister IBM virtual SCSI host driver\n");
4007         vio_unregister_driver(&ibmvscsis_driver);
4008         target_unregister_template(&ibmvscsis_ops);
4009         class_unregister(&ibmvscsis_class);
4010 }
4011
4012 MODULE_DESCRIPTION("IBMVSCSIS fabric driver");
4013 MODULE_AUTHOR("Bryant G. Ly and Michael Cyr");
4014 MODULE_LICENSE("GPL");
4015 MODULE_VERSION(IBMVSCSIS_VERSION);
4016 module_init(ibmvscsis_init);
4017 module_exit(ibmvscsis_exit);