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                         list_del(&cmd->list);
1174                         cmd->iue = iue;
1175                         cmd->type = UNSET_TYPE;
1176                         memset(&cmd->se_cmd, 0, sizeof(cmd->se_cmd));
1177                 } else {
1178                         srp_iu_put(iue);
1179                 }
1180         }
1181
1182         return cmd;
1183 }
1184
1185 /**
1186  * ibmvscsis_adapter_idle() - Helper function to handle idle adapter
1187  * @vscsi:      Pointer to our adapter structure
1188  *
1189  * This function is called when the adapter is idle when the driver
1190  * is attempting to clear an error condition.
1191  * The adapter is considered busy if any of its cmd queues
1192  * are non-empty. This function can be invoked
1193  * from the off level disconnect function.
1194  *
1195  * EXECUTION ENVIRONMENT:
1196  *      Process environment called with interrupt lock held
1197  */
1198 static void ibmvscsis_adapter_idle(struct scsi_info *vscsi)
1199 {
1200         int free_qs = false;
1201
1202         pr_debug("adapter_idle: flags 0x%x, state 0x%hx\n", vscsi->flags,
1203                  vscsi->state);
1204
1205         /* Only need to free qs if we're disconnecting from client */
1206         if (vscsi->state != WAIT_CONNECTION || vscsi->flags & TRANS_EVENT)
1207                 free_qs = true;
1208
1209         switch (vscsi->state) {
1210         case UNCONFIGURING:
1211                 ibmvscsis_free_command_q(vscsi);
1212                 dma_rmb();
1213                 isync();
1214                 if (vscsi->flags & CFG_SLEEPING) {
1215                         vscsi->flags &= ~CFG_SLEEPING;
1216                         complete(&vscsi->unconfig);
1217                 }
1218                 break;
1219         case ERR_DISCONNECT_RECONNECT:
1220                 ibmvscsis_reset_queue(vscsi);
1221                 pr_debug("adapter_idle, disc_rec: flags 0x%x\n", vscsi->flags);
1222                 break;
1223
1224         case ERR_DISCONNECT:
1225                 ibmvscsis_free_command_q(vscsi);
1226                 vscsi->flags &= ~(SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED);
1227                 vscsi->flags |= RESPONSE_Q_DOWN;
1228                 if (vscsi->tport.enabled)
1229                         vscsi->state = ERR_DISCONNECTED;
1230                 else
1231                         vscsi->state = WAIT_ENABLED;
1232                 pr_debug("adapter_idle, disc: flags 0x%x, state 0x%hx\n",
1233                          vscsi->flags, vscsi->state);
1234                 break;
1235
1236         case WAIT_IDLE:
1237                 vscsi->rsp_q_timer.timer_pops = 0;
1238                 vscsi->debit = 0;
1239                 vscsi->credit = 0;
1240                 if (vscsi->flags & TRANS_EVENT) {
1241                         vscsi->state = WAIT_CONNECTION;
1242                         vscsi->flags &= PRESERVE_FLAG_FIELDS;
1243                 } else {
1244                         vscsi->state = CONNECTED;
1245                         vscsi->flags &= ~DISCONNECT_SCHEDULED;
1246                 }
1247
1248                 pr_debug("adapter_idle, wait: flags 0x%x, state 0x%hx\n",
1249                          vscsi->flags, vscsi->state);
1250                 ibmvscsis_poll_cmd_q(vscsi);
1251                 break;
1252
1253         case ERR_DISCONNECTED:
1254                 vscsi->flags &= ~DISCONNECT_SCHEDULED;
1255                 pr_debug("adapter_idle, disconnected: flags 0x%x, state 0x%hx\n",
1256                          vscsi->flags, vscsi->state);
1257                 break;
1258
1259         default:
1260                 dev_err(&vscsi->dev, "adapter_idle: in invalid state %d\n",
1261                         vscsi->state);
1262                 break;
1263         }
1264
1265         if (free_qs)
1266                 ibmvscsis_free_cmd_qs(vscsi);
1267
1268         /*
1269          * There is a timing window where we could lose a disconnect request.
1270          * The known path to this window occurs during the DISCONNECT_RECONNECT
1271          * case above: reset_queue calls free_command_q, which will release the
1272          * interrupt lock.  During that time, a new post_disconnect call can be
1273          * made with a "more severe" state (DISCONNECT or UNCONFIGURING).
1274          * Because the DISCONNECT_SCHEDULED flag is already set, post_disconnect
1275          * will only set the new_state.  Now free_command_q reacquires the intr
1276          * lock and clears the DISCONNECT_SCHEDULED flag (using PRESERVE_FLAG_
1277          * FIELDS), and the disconnect is lost.  This is particularly bad when
1278          * the new disconnect was for UNCONFIGURING, since the unconfigure hangs
1279          * forever.
1280          * Fix is that free command queue sets acr state and acr flags if there
1281          * is a change under the lock
1282          * note free command queue writes to this state it clears it
1283          * before releasing the lock, different drivers call the free command
1284          * queue different times so dont initialize above
1285          */
1286         if (vscsi->phyp_acr_state != 0) {
1287                 /*
1288                  * set any bits in flags that may have been cleared by
1289                  * a call to free command queue in switch statement
1290                  * or reset queue
1291                  */
1292                 vscsi->flags |= vscsi->phyp_acr_flags;
1293                 ibmvscsis_post_disconnect(vscsi, vscsi->phyp_acr_state, 0);
1294                 vscsi->phyp_acr_state = 0;
1295                 vscsi->phyp_acr_flags = 0;
1296
1297                 pr_debug("adapter_idle: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
1298                          vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
1299                          vscsi->phyp_acr_state);
1300         }
1301
1302         pr_debug("Leaving adapter_idle: flags 0x%x, state 0x%hx, new_state 0x%x\n",
1303                  vscsi->flags, vscsi->state, vscsi->new_state);
1304 }
1305
1306 /**
1307  * ibmvscsis_copy_crq_packet() - Copy CRQ Packet
1308  * @vscsi:      Pointer to our adapter structure
1309  * @cmd:        Pointer to command element to use to process the request
1310  * @crq:        Pointer to CRQ entry containing the request
1311  *
1312  * Copy the srp information unit from the hosted
1313  * partition using remote dma
1314  *
1315  * EXECUTION ENVIRONMENT:
1316  *      Interrupt, interrupt lock held
1317  */
1318 static long ibmvscsis_copy_crq_packet(struct scsi_info *vscsi,
1319                                       struct ibmvscsis_cmd *cmd,
1320                                       struct viosrp_crq *crq)
1321 {
1322         struct iu_entry *iue = cmd->iue;
1323         long rc = 0;
1324         u16 len;
1325
1326         len = be16_to_cpu(crq->IU_length);
1327         if ((len > SRP_MAX_IU_LEN) || (len == 0)) {
1328                 dev_err(&vscsi->dev, "copy_crq: Invalid len %d passed", len);
1329                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1330                 return SRP_VIOLATION;
1331         }
1332
1333         rc = h_copy_rdma(len, vscsi->dds.window[REMOTE].liobn,
1334                          be64_to_cpu(crq->IU_data_ptr),
1335                          vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma);
1336
1337         switch (rc) {
1338         case H_SUCCESS:
1339                 cmd->init_time = mftb();
1340                 iue->remote_token = crq->IU_data_ptr;
1341                 iue->iu_len = len;
1342                 pr_debug("copy_crq: ioba 0x%llx, init_time 0x%llx\n",
1343                          be64_to_cpu(crq->IU_data_ptr), cmd->init_time);
1344                 break;
1345         case H_PERMISSION:
1346                 if (connection_broken(vscsi))
1347                         ibmvscsis_post_disconnect(vscsi,
1348                                                   ERR_DISCONNECT_RECONNECT,
1349                                                   (RESPONSE_Q_DOWN |
1350                                                    CLIENT_FAILED));
1351                 else
1352                         ibmvscsis_post_disconnect(vscsi,
1353                                                   ERR_DISCONNECT_RECONNECT, 0);
1354
1355                 dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
1356                         rc);
1357                 break;
1358         case H_DEST_PARM:
1359         case H_SOURCE_PARM:
1360         default:
1361                 dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
1362                         rc);
1363                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1364                 break;
1365         }
1366
1367         return rc;
1368 }
1369
1370 /**
1371  * ibmvscsis_adapter_info - Service an Adapter Info MAnagement Data gram
1372  * @vscsi:      Pointer to our adapter structure
1373  * @iue:        Information Unit containing the Adapter Info MAD request
1374  *
1375  * EXECUTION ENVIRONMENT:
1376  *      Interrupt adapter lock is held
1377  */
1378 static long ibmvscsis_adapter_info(struct scsi_info *vscsi,
1379                                    struct iu_entry *iue)
1380 {
1381         struct viosrp_adapter_info *mad = &vio_iu(iue)->mad.adapter_info;
1382         struct mad_adapter_info_data *info;
1383         uint flag_bits = 0;
1384         dma_addr_t token;
1385         long rc;
1386
1387         mad->common.status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1388
1389         if (be16_to_cpu(mad->common.length) > sizeof(*info)) {
1390                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1391                 return 0;
1392         }
1393
1394         info = dma_alloc_coherent(&vscsi->dma_dev->dev, sizeof(*info), &token,
1395                                   GFP_ATOMIC);
1396         if (!info) {
1397                 dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
1398                         iue->target);
1399                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1400                 return 0;
1401         }
1402
1403         /* Get remote info */
1404         rc = h_copy_rdma(be16_to_cpu(mad->common.length),
1405                          vscsi->dds.window[REMOTE].liobn,
1406                          be64_to_cpu(mad->buffer),
1407                          vscsi->dds.window[LOCAL].liobn, token);
1408
1409         if (rc != H_SUCCESS) {
1410                 if (rc == H_PERMISSION) {
1411                         if (connection_broken(vscsi))
1412                                 flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1413                 }
1414                 pr_warn("adapter_info: h_copy_rdma from client failed, rc %ld\n",
1415                         rc);
1416                 pr_debug("adapter_info: ioba 0x%llx, flags 0x%x, flag_bits 0x%x\n",
1417                          be64_to_cpu(mad->buffer), vscsi->flags, flag_bits);
1418                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1419                                           flag_bits);
1420                 goto free_dma;
1421         }
1422
1423         /*
1424          * Copy client info, but ignore partition number, which we
1425          * already got from phyp - unless we failed to get it from
1426          * phyp (e.g. if we're running on a p5 system).
1427          */
1428         if (vscsi->client_data.partition_number == 0)
1429                 vscsi->client_data.partition_number =
1430                         be32_to_cpu(info->partition_number);
1431         strncpy(vscsi->client_data.srp_version, info->srp_version,
1432                 sizeof(vscsi->client_data.srp_version));
1433         strncpy(vscsi->client_data.partition_name, info->partition_name,
1434                 sizeof(vscsi->client_data.partition_name));
1435         vscsi->client_data.mad_version = be32_to_cpu(info->mad_version);
1436         vscsi->client_data.os_type = be32_to_cpu(info->os_type);
1437
1438         /* Copy our info */
1439         strncpy(info->srp_version, SRP_VERSION,
1440                 sizeof(info->srp_version));
1441         strncpy(info->partition_name, vscsi->dds.partition_name,
1442                 sizeof(info->partition_name));
1443         info->partition_number = cpu_to_be32(vscsi->dds.partition_num);
1444         info->mad_version = cpu_to_be32(MAD_VERSION_1);
1445         info->os_type = cpu_to_be32(LINUX);
1446         memset(&info->port_max_txu[0], 0, sizeof(info->port_max_txu));
1447         info->port_max_txu[0] = cpu_to_be32(MAX_TXU);
1448
1449         dma_wmb();
1450         rc = h_copy_rdma(sizeof(*info), vscsi->dds.window[LOCAL].liobn,
1451                          token, vscsi->dds.window[REMOTE].liobn,
1452                          be64_to_cpu(mad->buffer));
1453         switch (rc) {
1454         case H_SUCCESS:
1455                 break;
1456
1457         case H_SOURCE_PARM:
1458         case H_DEST_PARM:
1459         case H_PERMISSION:
1460                 if (connection_broken(vscsi))
1461                         flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1462         default:
1463                 dev_err(&vscsi->dev, "adapter_info: h_copy_rdma to client failed, rc %ld\n",
1464                         rc);
1465                 ibmvscsis_post_disconnect(vscsi,
1466                                           ERR_DISCONNECT_RECONNECT,
1467                                           flag_bits);
1468                 break;
1469         }
1470
1471 free_dma:
1472         dma_free_coherent(&vscsi->dma_dev->dev, sizeof(*info), info, token);
1473         pr_debug("Leaving adapter_info, rc %ld\n", rc);
1474
1475         return rc;
1476 }
1477
1478 /**
1479  * ibmvscsis_cap_mad() - Service a Capabilities MAnagement Data gram
1480  * @vscsi:      Pointer to our adapter structure
1481  * @iue:        Information Unit containing the Capabilities MAD request
1482  *
1483  * NOTE: if you return an error from this routine you must be
1484  * disconnecting or you will cause a hang
1485  *
1486  * EXECUTION ENVIRONMENT:
1487  *      Interrupt called with adapter lock held
1488  */
1489 static int ibmvscsis_cap_mad(struct scsi_info *vscsi, struct iu_entry *iue)
1490 {
1491         struct viosrp_capabilities *mad = &vio_iu(iue)->mad.capabilities;
1492         struct capabilities *cap;
1493         struct mad_capability_common *common;
1494         dma_addr_t token;
1495         u16 olen, len, status, min_len, cap_len;
1496         u32 flag;
1497         uint flag_bits = 0;
1498         long rc = 0;
1499
1500         olen = be16_to_cpu(mad->common.length);
1501         /*
1502          * struct capabilities hardcodes a couple capabilities after the
1503          * header, but the capabilities can actually be in any order.
1504          */
1505         min_len = offsetof(struct capabilities, migration);
1506         if ((olen < min_len) || (olen > PAGE_SIZE)) {
1507                 pr_warn("cap_mad: invalid len %d\n", olen);
1508                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1509                 return 0;
1510         }
1511
1512         cap = dma_alloc_coherent(&vscsi->dma_dev->dev, olen, &token,
1513                                  GFP_ATOMIC);
1514         if (!cap) {
1515                 dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
1516                         iue->target);
1517                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1518                 return 0;
1519         }
1520         rc = h_copy_rdma(olen, vscsi->dds.window[REMOTE].liobn,
1521                          be64_to_cpu(mad->buffer),
1522                          vscsi->dds.window[LOCAL].liobn, token);
1523         if (rc == H_SUCCESS) {
1524                 strncpy(cap->name, dev_name(&vscsi->dma_dev->dev),
1525                         SRP_MAX_LOC_LEN);
1526
1527                 len = olen - min_len;
1528                 status = VIOSRP_MAD_SUCCESS;
1529                 common = (struct mad_capability_common *)&cap->migration;
1530
1531                 while ((len > 0) && (status == VIOSRP_MAD_SUCCESS) && !rc) {
1532                         pr_debug("cap_mad: len left %hd, cap type %d, cap len %hd\n",
1533                                  len, be32_to_cpu(common->cap_type),
1534                                  be16_to_cpu(common->length));
1535
1536                         cap_len = be16_to_cpu(common->length);
1537                         if (cap_len > len) {
1538                                 dev_err(&vscsi->dev, "cap_mad: cap len mismatch with total len\n");
1539                                 status = VIOSRP_MAD_FAILED;
1540                                 break;
1541                         }
1542
1543                         if (cap_len == 0) {
1544                                 dev_err(&vscsi->dev, "cap_mad: cap len is 0\n");
1545                                 status = VIOSRP_MAD_FAILED;
1546                                 break;
1547                         }
1548
1549                         switch (common->cap_type) {
1550                         default:
1551                                 pr_debug("cap_mad: unsupported capability\n");
1552                                 common->server_support = 0;
1553                                 flag = cpu_to_be32((u32)CAP_LIST_SUPPORTED);
1554                                 cap->flags &= ~flag;
1555                                 break;
1556                         }
1557
1558                         len = len - cap_len;
1559                         common = (struct mad_capability_common *)
1560                                 ((char *)common + cap_len);
1561                 }
1562
1563                 mad->common.status = cpu_to_be16(status);
1564
1565                 dma_wmb();
1566                 rc = h_copy_rdma(olen, vscsi->dds.window[LOCAL].liobn, token,
1567                                  vscsi->dds.window[REMOTE].liobn,
1568                                  be64_to_cpu(mad->buffer));
1569
1570                 if (rc != H_SUCCESS) {
1571                         pr_debug("cap_mad: failed to copy to client, rc %ld\n",
1572                                  rc);
1573
1574                         if (rc == H_PERMISSION) {
1575                                 if (connection_broken(vscsi))
1576                                         flag_bits = (RESPONSE_Q_DOWN |
1577                                                      CLIENT_FAILED);
1578                         }
1579
1580                         pr_warn("cap_mad: error copying data to client, rc %ld\n",
1581                                 rc);
1582                         ibmvscsis_post_disconnect(vscsi,
1583                                                   ERR_DISCONNECT_RECONNECT,
1584                                                   flag_bits);
1585                 }
1586         }
1587
1588         dma_free_coherent(&vscsi->dma_dev->dev, olen, cap, token);
1589
1590         pr_debug("Leaving cap_mad, rc %ld, client_cap 0x%x\n",
1591                  rc, vscsi->client_cap);
1592
1593         return rc;
1594 }
1595
1596 /**
1597  * ibmvscsis_process_mad() - Service a MAnagement Data gram
1598  * @vscsi:      Pointer to our adapter structure
1599  * @iue:        Information Unit containing the MAD request
1600  *
1601  * Must be called with interrupt lock held.
1602  */
1603 static long ibmvscsis_process_mad(struct scsi_info *vscsi, struct iu_entry *iue)
1604 {
1605         struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
1606         struct viosrp_empty_iu *empty;
1607         long rc = ADAPT_SUCCESS;
1608
1609         switch (be32_to_cpu(mad->type)) {
1610         case VIOSRP_EMPTY_IU_TYPE:
1611                 empty = &vio_iu(iue)->mad.empty_iu;
1612                 vscsi->empty_iu_id = be64_to_cpu(empty->buffer);
1613                 vscsi->empty_iu_tag = be64_to_cpu(empty->common.tag);
1614                 mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1615                 break;
1616         case VIOSRP_ADAPTER_INFO_TYPE:
1617                 rc = ibmvscsis_adapter_info(vscsi, iue);
1618                 break;
1619         case VIOSRP_CAPABILITIES_TYPE:
1620                 rc = ibmvscsis_cap_mad(vscsi, iue);
1621                 break;
1622         case VIOSRP_ENABLE_FAST_FAIL:
1623                 if (vscsi->state == CONNECTED) {
1624                         vscsi->fast_fail = true;
1625                         mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1626                 } else {
1627                         pr_warn("fast fail mad sent after login\n");
1628                         mad->status = cpu_to_be16(VIOSRP_MAD_FAILED);
1629                 }
1630                 break;
1631         default:
1632                 mad->status = cpu_to_be16(VIOSRP_MAD_NOT_SUPPORTED);
1633                 break;
1634         }
1635
1636         return rc;
1637 }
1638
1639 /**
1640  * srp_snd_msg_failed() - Handle an error when sending a response
1641  * @vscsi:      Pointer to our adapter structure
1642  * @rc:         The return code from the h_send_crq command
1643  *
1644  * Must be called with interrupt lock held.
1645  */
1646 static void srp_snd_msg_failed(struct scsi_info *vscsi, long rc)
1647 {
1648         ktime_t kt;
1649
1650         if (rc != H_DROPPED) {
1651                 ibmvscsis_free_cmd_qs(vscsi);
1652
1653                 if (rc == H_CLOSED)
1654                         vscsi->flags |= CLIENT_FAILED;
1655
1656                 /* don't flag the same problem multiple times */
1657                 if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
1658                         vscsi->flags |= RESPONSE_Q_DOWN;
1659                         if (!(vscsi->state & (ERR_DISCONNECT |
1660                                               ERR_DISCONNECT_RECONNECT |
1661                                               ERR_DISCONNECTED | UNDEFINED))) {
1662                                 dev_err(&vscsi->dev, "snd_msg_failed: setting RESPONSE_Q_DOWN, state 0x%hx, flags 0x%x, rc %ld\n",
1663                                         vscsi->state, vscsi->flags, rc);
1664                         }
1665                         ibmvscsis_post_disconnect(vscsi,
1666                                                   ERR_DISCONNECT_RECONNECT, 0);
1667                 }
1668                 return;
1669         }
1670
1671         /*
1672          * The response queue is full.
1673          * If the server is processing SRP requests, i.e.
1674          * the client has successfully done an
1675          * SRP_LOGIN, then it will wait forever for room in
1676          * the queue.  However if the system admin
1677          * is attempting to unconfigure the server then one
1678          * or more children will be in a state where
1679          * they are being removed. So if there is even one
1680          * child being removed then the driver assumes
1681          * the system admin is attempting to break the
1682          * connection with the client and MAX_TIMER_POPS
1683          * is honored.
1684          */
1685         if ((vscsi->rsp_q_timer.timer_pops < MAX_TIMER_POPS) ||
1686             (vscsi->state == SRP_PROCESSING)) {
1687                 pr_debug("snd_msg_failed: response queue full, flags 0x%x, timer started %d, pops %d\n",
1688                          vscsi->flags, (int)vscsi->rsp_q_timer.started,
1689                          vscsi->rsp_q_timer.timer_pops);
1690
1691                 /*
1692                  * Check if the timer is running; if it
1693                  * is not then start it up.
1694                  */
1695                 if (!vscsi->rsp_q_timer.started) {
1696                         if (vscsi->rsp_q_timer.timer_pops <
1697                             MAX_TIMER_POPS) {
1698                                 kt = WAIT_NANO_SECONDS;
1699                         } else {
1700                                 /*
1701                                  * slide the timeslice if the maximum
1702                                  * timer pops have already happened
1703                                  */
1704                                 kt = ktime_set(WAIT_SECONDS, 0);
1705                         }
1706
1707                         vscsi->rsp_q_timer.started = true;
1708                         hrtimer_start(&vscsi->rsp_q_timer.timer, kt,
1709                                       HRTIMER_MODE_REL);
1710                 }
1711         } else {
1712                 /*
1713                  * TBD: Do we need to worry about this? Need to get
1714                  *      remove working.
1715                  */
1716                 /*
1717                  * waited a long time and it appears the system admin
1718                  * is bring this driver down
1719                  */
1720                 vscsi->flags |= RESPONSE_Q_DOWN;
1721                 ibmvscsis_free_cmd_qs(vscsi);
1722                 /*
1723                  * if the driver is already attempting to disconnect
1724                  * from the client and has already logged an error
1725                  * trace this event but don't put it in the error log
1726                  */
1727                 if (!(vscsi->state & (ERR_DISCONNECT |
1728                                       ERR_DISCONNECT_RECONNECT |
1729                                       ERR_DISCONNECTED | UNDEFINED))) {
1730                         dev_err(&vscsi->dev, "client crq full too long\n");
1731                         ibmvscsis_post_disconnect(vscsi,
1732                                                   ERR_DISCONNECT_RECONNECT,
1733                                                   0);
1734                 }
1735         }
1736 }
1737
1738 /**
1739  * ibmvscsis_send_messages() - Send a Response
1740  * @vscsi:      Pointer to our adapter structure
1741  *
1742  * Send a response, first checking the waiting queue. Responses are
1743  * sent in order they are received. If the response cannot be sent,
1744  * because the client queue is full, it stays on the waiting queue.
1745  *
1746  * PRECONDITION:
1747  *      Called with interrupt lock held
1748  */
1749 static void ibmvscsis_send_messages(struct scsi_info *vscsi)
1750 {
1751         u64 msg_hi = 0;
1752         /* note do not attmempt to access the IU_data_ptr with this pointer
1753          * it is not valid
1754          */
1755         struct viosrp_crq *crq = (struct viosrp_crq *)&msg_hi;
1756         struct ibmvscsis_cmd *cmd, *nxt;
1757         struct iu_entry *iue;
1758         long rc = ADAPT_SUCCESS;
1759
1760         if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
1761                 list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp, list) {
1762                         iue = cmd->iue;
1763
1764                         crq->valid = VALID_CMD_RESP_EL;
1765                         crq->format = cmd->rsp.format;
1766
1767                         if (cmd->flags & CMD_FAST_FAIL)
1768                                 crq->status = VIOSRP_ADAPTER_FAIL;
1769
1770                         crq->IU_length = cpu_to_be16(cmd->rsp.len);
1771
1772                         rc = h_send_crq(vscsi->dma_dev->unit_address,
1773                                         be64_to_cpu(msg_hi),
1774                                         be64_to_cpu(cmd->rsp.tag));
1775
1776                         pr_debug("send_messages: cmd %p, tag 0x%llx, rc %ld\n",
1777                                  cmd, be64_to_cpu(cmd->rsp.tag), rc);
1778
1779                         /* if all ok free up the command element resources */
1780                         if (rc == H_SUCCESS) {
1781                                 /* some movement has occurred */
1782                                 vscsi->rsp_q_timer.timer_pops = 0;
1783                                 list_del(&cmd->list);
1784
1785                                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1786                         } else {
1787                                 srp_snd_msg_failed(vscsi, rc);
1788                                 break;
1789                         }
1790                 }
1791
1792                 if (!rc) {
1793                         /*
1794                          * The timer could pop with the queue empty.  If
1795                          * this happens, rc will always indicate a
1796                          * success; clear the pop count.
1797                          */
1798                         vscsi->rsp_q_timer.timer_pops = 0;
1799                 }
1800         } else {
1801                 ibmvscsis_free_cmd_qs(vscsi);
1802         }
1803 }
1804
1805 /* Called with intr lock held */
1806 static void ibmvscsis_send_mad_resp(struct scsi_info *vscsi,
1807                                     struct ibmvscsis_cmd *cmd,
1808                                     struct viosrp_crq *crq)
1809 {
1810         struct iu_entry *iue = cmd->iue;
1811         struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
1812         uint flag_bits = 0;
1813         long rc;
1814
1815         dma_wmb();
1816         rc = h_copy_rdma(sizeof(struct mad_common),
1817                          vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
1818                          vscsi->dds.window[REMOTE].liobn,
1819                          be64_to_cpu(crq->IU_data_ptr));
1820         if (!rc) {
1821                 cmd->rsp.format = VIOSRP_MAD_FORMAT;
1822                 cmd->rsp.len = sizeof(struct mad_common);
1823                 cmd->rsp.tag = mad->tag;
1824                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
1825                 ibmvscsis_send_messages(vscsi);
1826         } else {
1827                 pr_debug("Error sending mad response, rc %ld\n", rc);
1828                 if (rc == H_PERMISSION) {
1829                         if (connection_broken(vscsi))
1830                                 flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1831                 }
1832                 dev_err(&vscsi->dev, "mad: failed to copy to client, rc %ld\n",
1833                         rc);
1834
1835                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1836                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1837                                           flag_bits);
1838         }
1839 }
1840
1841 /**
1842  * ibmvscsis_mad() - Service a MAnagement Data gram.
1843  * @vscsi:      Pointer to our adapter structure
1844  * @crq:        Pointer to the CRQ entry containing the MAD request
1845  *
1846  * EXECUTION ENVIRONMENT:
1847  *      Interrupt, called with adapter lock held
1848  */
1849 static long ibmvscsis_mad(struct scsi_info *vscsi, struct viosrp_crq *crq)
1850 {
1851         struct iu_entry *iue;
1852         struct ibmvscsis_cmd *cmd;
1853         struct mad_common *mad;
1854         long rc = ADAPT_SUCCESS;
1855
1856         switch (vscsi->state) {
1857                 /*
1858                  * We have not exchanged Init Msgs yet, so this MAD was sent
1859                  * before the last Transport Event; client will not be
1860                  * expecting a response.
1861                  */
1862         case WAIT_CONNECTION:
1863                 pr_debug("mad: in Wait Connection state, ignoring MAD, flags %d\n",
1864                          vscsi->flags);
1865                 return ADAPT_SUCCESS;
1866
1867         case SRP_PROCESSING:
1868         case CONNECTED:
1869                 break;
1870
1871                 /*
1872                  * We should never get here while we're in these states.
1873                  * Just log an error and get out.
1874                  */
1875         case UNCONFIGURING:
1876         case WAIT_IDLE:
1877         case ERR_DISCONNECT:
1878         case ERR_DISCONNECT_RECONNECT:
1879         default:
1880                 dev_err(&vscsi->dev, "mad: invalid adapter state %d for mad\n",
1881                         vscsi->state);
1882                 return ADAPT_SUCCESS;
1883         }
1884
1885         cmd = ibmvscsis_get_free_cmd(vscsi);
1886         if (!cmd) {
1887                 dev_err(&vscsi->dev, "mad: failed to get cmd, debit %d\n",
1888                         vscsi->debit);
1889                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1890                 return ERROR;
1891         }
1892         iue = cmd->iue;
1893         cmd->type = ADAPTER_MAD;
1894
1895         rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
1896         if (!rc) {
1897                 mad = (struct mad_common *)&vio_iu(iue)->mad;
1898
1899                 pr_debug("mad: type %d\n", be32_to_cpu(mad->type));
1900
1901                 rc = ibmvscsis_process_mad(vscsi, iue);
1902
1903                 pr_debug("mad: status %hd, rc %ld\n", be16_to_cpu(mad->status),
1904                          rc);
1905
1906                 if (!rc)
1907                         ibmvscsis_send_mad_resp(vscsi, cmd, crq);
1908         } else {
1909                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1910         }
1911
1912         pr_debug("Leaving mad, rc %ld\n", rc);
1913         return rc;
1914 }
1915
1916 /**
1917  * ibmvscsis_login_rsp() - Create/copy a login response notice to the client
1918  * @vscsi:      Pointer to our adapter structure
1919  * @cmd:        Pointer to the command for the SRP Login request
1920  *
1921  * EXECUTION ENVIRONMENT:
1922  *      Interrupt, interrupt lock held
1923  */
1924 static long ibmvscsis_login_rsp(struct scsi_info *vscsi,
1925                                 struct ibmvscsis_cmd *cmd)
1926 {
1927         struct iu_entry *iue = cmd->iue;
1928         struct srp_login_rsp *rsp = &vio_iu(iue)->srp.login_rsp;
1929         struct format_code *fmt;
1930         uint flag_bits = 0;
1931         long rc = ADAPT_SUCCESS;
1932
1933         memset(rsp, 0, sizeof(struct srp_login_rsp));
1934
1935         rsp->opcode = SRP_LOGIN_RSP;
1936         rsp->req_lim_delta = cpu_to_be32(vscsi->request_limit);
1937         rsp->tag = cmd->rsp.tag;
1938         rsp->max_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
1939         rsp->max_ti_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
1940         fmt = (struct format_code *)&rsp->buf_fmt;
1941         fmt->buffers = SUPPORTED_FORMATS;
1942         vscsi->credit = 0;
1943
1944         cmd->rsp.len = sizeof(struct srp_login_rsp);
1945
1946         dma_wmb();
1947         rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
1948                          iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
1949                          be64_to_cpu(iue->remote_token));
1950
1951         switch (rc) {
1952         case H_SUCCESS:
1953                 break;
1954
1955         case H_PERMISSION:
1956                 if (connection_broken(vscsi))
1957                         flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
1958                 dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
1959                         rc);
1960                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1961                                           flag_bits);
1962                 break;
1963         case H_SOURCE_PARM:
1964         case H_DEST_PARM:
1965         default:
1966                 dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
1967                         rc);
1968                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1969                 break;
1970         }
1971
1972         return rc;
1973 }
1974
1975 /**
1976  * ibmvscsis_srp_login_rej() - Create/copy a login rejection notice to client
1977  * @vscsi:      Pointer to our adapter structure
1978  * @cmd:        Pointer to the command for the SRP Login request
1979  * @reason:     The reason the SRP Login is being rejected, per SRP protocol
1980  *
1981  * EXECUTION ENVIRONMENT:
1982  *      Interrupt, interrupt lock held
1983  */
1984 static long ibmvscsis_srp_login_rej(struct scsi_info *vscsi,
1985                                     struct ibmvscsis_cmd *cmd, u32 reason)
1986 {
1987         struct iu_entry *iue = cmd->iue;
1988         struct srp_login_rej *rej = &vio_iu(iue)->srp.login_rej;
1989         struct format_code *fmt;
1990         uint flag_bits = 0;
1991         long rc = ADAPT_SUCCESS;
1992
1993         memset(rej, 0, sizeof(*rej));
1994
1995         rej->opcode = SRP_LOGIN_REJ;
1996         rej->reason = cpu_to_be32(reason);
1997         rej->tag = cmd->rsp.tag;
1998         fmt = (struct format_code *)&rej->buf_fmt;
1999         fmt->buffers = SUPPORTED_FORMATS;
2000
2001         cmd->rsp.len = sizeof(*rej);
2002
2003         dma_wmb();
2004         rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
2005                          iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
2006                          be64_to_cpu(iue->remote_token));
2007
2008         switch (rc) {
2009         case H_SUCCESS:
2010                 break;
2011         case H_PERMISSION:
2012                 if (connection_broken(vscsi))
2013                         flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
2014                 dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
2015                         rc);
2016                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
2017                                           flag_bits);
2018                 break;
2019         case H_SOURCE_PARM:
2020         case H_DEST_PARM:
2021         default:
2022                 dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
2023                         rc);
2024                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2025                 break;
2026         }
2027
2028         return rc;
2029 }
2030
2031 static int ibmvscsis_make_nexus(struct ibmvscsis_tport *tport)
2032 {
2033         char *name = tport->tport_name;
2034         struct ibmvscsis_nexus *nexus;
2035         int rc;
2036
2037         if (tport->ibmv_nexus) {
2038                 pr_debug("tport->ibmv_nexus already exists\n");
2039                 return 0;
2040         }
2041
2042         nexus = kzalloc(sizeof(*nexus), GFP_KERNEL);
2043         if (!nexus) {
2044                 pr_err("Unable to allocate struct ibmvscsis_nexus\n");
2045                 return -ENOMEM;
2046         }
2047
2048         nexus->se_sess = target_alloc_session(&tport->se_tpg, 0, 0,
2049                                               TARGET_PROT_NORMAL, name, nexus,
2050                                               NULL);
2051         if (IS_ERR(nexus->se_sess)) {
2052                 rc = PTR_ERR(nexus->se_sess);
2053                 goto transport_init_fail;
2054         }
2055
2056         tport->ibmv_nexus = nexus;
2057
2058         return 0;
2059
2060 transport_init_fail:
2061         kfree(nexus);
2062         return rc;
2063 }
2064
2065 static int ibmvscsis_drop_nexus(struct ibmvscsis_tport *tport)
2066 {
2067         struct se_session *se_sess;
2068         struct ibmvscsis_nexus *nexus;
2069
2070         nexus = tport->ibmv_nexus;
2071         if (!nexus)
2072                 return -ENODEV;
2073
2074         se_sess = nexus->se_sess;
2075         if (!se_sess)
2076                 return -ENODEV;
2077
2078         /*
2079          * Release the SCSI I_T Nexus to the emulated ibmvscsis Target Port
2080          */
2081         target_wait_for_sess_cmds(se_sess);
2082         transport_deregister_session_configfs(se_sess);
2083         transport_deregister_session(se_sess);
2084         tport->ibmv_nexus = NULL;
2085         kfree(nexus);
2086
2087         return 0;
2088 }
2089
2090 /**
2091  * ibmvscsis_srp_login() - Process an SRP Login Request
2092  * @vscsi:      Pointer to our adapter structure
2093  * @cmd:        Command element to use to process the SRP Login request
2094  * @crq:        Pointer to CRQ entry containing the SRP Login request
2095  *
2096  * EXECUTION ENVIRONMENT:
2097  *      Interrupt, called with interrupt lock held
2098  */
2099 static long ibmvscsis_srp_login(struct scsi_info *vscsi,
2100                                 struct ibmvscsis_cmd *cmd,
2101                                 struct viosrp_crq *crq)
2102 {
2103         struct iu_entry *iue = cmd->iue;
2104         struct srp_login_req *req = &vio_iu(iue)->srp.login_req;
2105         struct port_id {
2106                 __be64 id_extension;
2107                 __be64 io_guid;
2108         } *iport, *tport;
2109         struct format_code *fmt;
2110         u32 reason = 0x0;
2111         long rc = ADAPT_SUCCESS;
2112
2113         iport = (struct port_id *)req->initiator_port_id;
2114         tport = (struct port_id *)req->target_port_id;
2115         fmt = (struct format_code *)&req->req_buf_fmt;
2116         if (be32_to_cpu(req->req_it_iu_len) > SRP_MAX_IU_LEN)
2117                 reason = SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE;
2118         else if (be32_to_cpu(req->req_it_iu_len) < 64)
2119                 reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
2120         else if ((be64_to_cpu(iport->id_extension) > (MAX_NUM_PORTS - 1)) ||
2121                  (be64_to_cpu(tport->id_extension) > (MAX_NUM_PORTS - 1)))
2122                 reason = SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL;
2123         else if (req->req_flags & SRP_MULTICHAN_MULTI)
2124                 reason = SRP_LOGIN_REJ_MULTI_CHANNEL_UNSUPPORTED;
2125         else if (fmt->buffers & (~SUPPORTED_FORMATS))
2126                 reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
2127         else if ((fmt->buffers & SUPPORTED_FORMATS) == 0)
2128                 reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
2129
2130         if (vscsi->state == SRP_PROCESSING)
2131                 reason = SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED;
2132
2133         rc = ibmvscsis_make_nexus(&vscsi->tport);
2134         if (rc)
2135                 reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
2136
2137         cmd->rsp.format = VIOSRP_SRP_FORMAT;
2138         cmd->rsp.tag = req->tag;
2139
2140         pr_debug("srp_login: reason 0x%x\n", reason);
2141
2142         if (reason)
2143                 rc = ibmvscsis_srp_login_rej(vscsi, cmd, reason);
2144         else
2145                 rc = ibmvscsis_login_rsp(vscsi, cmd);
2146
2147         if (!rc) {
2148                 if (!reason)
2149                         vscsi->state = SRP_PROCESSING;
2150
2151                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
2152                 ibmvscsis_send_messages(vscsi);
2153         } else {
2154                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2155         }
2156
2157         pr_debug("Leaving srp_login, rc %ld\n", rc);
2158         return rc;
2159 }
2160
2161 /**
2162  * ibmvscsis_srp_i_logout() - Helper Function to close I_T Nexus
2163  * @vscsi:      Pointer to our adapter structure
2164  * @cmd:        Command element to use to process the Implicit Logout request
2165  * @crq:        Pointer to CRQ entry containing the Implicit Logout request
2166  *
2167  * Do the logic to close the I_T nexus.  This function may not
2168  * behave to specification.
2169  *
2170  * EXECUTION ENVIRONMENT:
2171  *      Interrupt, interrupt lock held
2172  */
2173 static long ibmvscsis_srp_i_logout(struct scsi_info *vscsi,
2174                                    struct ibmvscsis_cmd *cmd,
2175                                    struct viosrp_crq *crq)
2176 {
2177         struct iu_entry *iue = cmd->iue;
2178         struct srp_i_logout *log_out = &vio_iu(iue)->srp.i_logout;
2179         long rc = ADAPT_SUCCESS;
2180
2181         if ((vscsi->debit > 0) || !list_empty(&vscsi->schedule_q) ||
2182             !list_empty(&vscsi->waiting_rsp)) {
2183                 dev_err(&vscsi->dev, "i_logout: outstanding work\n");
2184                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
2185         } else {
2186                 cmd->rsp.format = SRP_FORMAT;
2187                 cmd->rsp.tag = log_out->tag;
2188                 cmd->rsp.len = sizeof(struct mad_common);
2189                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
2190                 ibmvscsis_send_messages(vscsi);
2191
2192                 ibmvscsis_post_disconnect(vscsi, WAIT_IDLE, 0);
2193         }
2194
2195         return rc;
2196 }
2197
2198 /* Called with intr lock held */
2199 static void ibmvscsis_srp_cmd(struct scsi_info *vscsi, struct viosrp_crq *crq)
2200 {
2201         struct ibmvscsis_cmd *cmd;
2202         struct iu_entry *iue;
2203         struct srp_cmd *srp;
2204         struct srp_tsk_mgmt *tsk;
2205         long rc;
2206
2207         if (vscsi->request_limit - vscsi->debit <= 0) {
2208                 /* Client has exceeded request limit */
2209                 dev_err(&vscsi->dev, "Client exceeded the request limit (%d), debit %d\n",
2210                         vscsi->request_limit, vscsi->debit);
2211                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2212                 return;
2213         }
2214
2215         cmd = ibmvscsis_get_free_cmd(vscsi);
2216         if (!cmd) {
2217                 dev_err(&vscsi->dev, "srp_cmd failed to get cmd, debit %d\n",
2218                         vscsi->debit);
2219                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2220                 return;
2221         }
2222         iue = cmd->iue;
2223         srp = &vio_iu(iue)->srp.cmd;
2224
2225         rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
2226         if (rc) {
2227                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2228                 return;
2229         }
2230
2231         if (vscsi->state == SRP_PROCESSING) {
2232                 switch (srp->opcode) {
2233                 case SRP_LOGIN_REQ:
2234                         rc = ibmvscsis_srp_login(vscsi, cmd, crq);
2235                         break;
2236
2237                 case SRP_TSK_MGMT:
2238                         tsk = &vio_iu(iue)->srp.tsk_mgmt;
2239                         pr_debug("tsk_mgmt tag: %llu (0x%llx)\n", tsk->tag,
2240                                  tsk->tag);
2241                         cmd->rsp.tag = tsk->tag;
2242                         vscsi->debit += 1;
2243                         cmd->type = TASK_MANAGEMENT;
2244                         list_add_tail(&cmd->list, &vscsi->schedule_q);
2245                         queue_work(vscsi->work_q, &cmd->work);
2246                         break;
2247
2248                 case SRP_CMD:
2249                         pr_debug("srp_cmd tag: %llu (0x%llx)\n", srp->tag,
2250                                  srp->tag);
2251                         cmd->rsp.tag = srp->tag;
2252                         vscsi->debit += 1;
2253                         cmd->type = SCSI_CDB;
2254                         /*
2255                          * We want to keep track of work waiting for
2256                          * the workqueue.
2257                          */
2258                         list_add_tail(&cmd->list, &vscsi->schedule_q);
2259                         queue_work(vscsi->work_q, &cmd->work);
2260                         break;
2261
2262                 case SRP_I_LOGOUT:
2263                         rc = ibmvscsis_srp_i_logout(vscsi, cmd, crq);
2264                         break;
2265
2266                 case SRP_CRED_RSP:
2267                 case SRP_AER_RSP:
2268                 default:
2269                         ibmvscsis_free_cmd_resources(vscsi, cmd);
2270                         dev_err(&vscsi->dev, "invalid srp cmd, opcode %d\n",
2271                                 (uint)srp->opcode);
2272                         ibmvscsis_post_disconnect(vscsi,
2273                                                   ERR_DISCONNECT_RECONNECT, 0);
2274                         break;
2275                 }
2276         } else if (srp->opcode == SRP_LOGIN_REQ && vscsi->state == CONNECTED) {
2277                 rc = ibmvscsis_srp_login(vscsi, cmd, crq);
2278         } else {
2279                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2280                 dev_err(&vscsi->dev, "Invalid state %d to handle srp cmd\n",
2281                         vscsi->state);
2282                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2283         }
2284 }
2285
2286 /**
2287  * ibmvscsis_ping_response() - Respond to a ping request
2288  * @vscsi:      Pointer to our adapter structure
2289  *
2290  * Let the client know that the server is alive and waiting on
2291  * its native I/O stack.
2292  * If any type of error occurs from the call to queue a ping
2293  * response then the client is either not accepting or receiving
2294  * interrupts.  Disconnect with an error.
2295  *
2296  * EXECUTION ENVIRONMENT:
2297  *      Interrupt, interrupt lock held
2298  */
2299 static long ibmvscsis_ping_response(struct scsi_info *vscsi)
2300 {
2301         struct viosrp_crq *crq;
2302         u64 buffer[2] = { 0, 0 };
2303         long rc;
2304
2305         crq = (struct viosrp_crq *)&buffer;
2306         crq->valid = VALID_CMD_RESP_EL;
2307         crq->format = (u8)MESSAGE_IN_CRQ;
2308         crq->status = PING_RESPONSE;
2309
2310         rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
2311                         cpu_to_be64(buffer[MSG_LOW]));
2312
2313         switch (rc) {
2314         case H_SUCCESS:
2315                 break;
2316         case H_CLOSED:
2317                 vscsi->flags |= CLIENT_FAILED;
2318         case H_DROPPED:
2319                 vscsi->flags |= RESPONSE_Q_DOWN;
2320         case H_REMOTE_PARM:
2321                 dev_err(&vscsi->dev, "ping_response: h_send_crq failed, rc %ld\n",
2322                         rc);
2323                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2324                 break;
2325         default:
2326                 dev_err(&vscsi->dev, "ping_response: h_send_crq returned unknown rc %ld\n",
2327                         rc);
2328                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
2329                 break;
2330         }
2331
2332         return rc;
2333 }
2334
2335 /**
2336  * ibmvscsis_parse_command() - Parse an element taken from the cmd rsp queue.
2337  * @vscsi:      Pointer to our adapter structure
2338  * @crq:        Pointer to CRQ element containing the SRP request
2339  *
2340  * This function will return success if the command queue element is valid
2341  * and the srp iu or MAD request it pointed to was also valid.  That does
2342  * not mean that an error was not returned to the client.
2343  *
2344  * EXECUTION ENVIRONMENT:
2345  *      Interrupt, intr lock held
2346  */
2347 static long ibmvscsis_parse_command(struct scsi_info *vscsi,
2348                                     struct viosrp_crq *crq)
2349 {
2350         long rc = ADAPT_SUCCESS;
2351
2352         switch (crq->valid) {
2353         case VALID_CMD_RESP_EL:
2354                 switch (crq->format) {
2355                 case OS400_FORMAT:
2356                 case AIX_FORMAT:
2357                 case LINUX_FORMAT:
2358                 case MAD_FORMAT:
2359                         if (vscsi->flags & PROCESSING_MAD) {
2360                                 rc = ERROR;
2361                                 dev_err(&vscsi->dev, "parse_command: already processing mad\n");
2362                                 ibmvscsis_post_disconnect(vscsi,
2363                                                        ERR_DISCONNECT_RECONNECT,
2364                                                        0);
2365                         } else {
2366                                 vscsi->flags |= PROCESSING_MAD;
2367                                 rc = ibmvscsis_mad(vscsi, crq);
2368                         }
2369                         break;
2370
2371                 case SRP_FORMAT:
2372                         ibmvscsis_srp_cmd(vscsi, crq);
2373                         break;
2374
2375                 case MESSAGE_IN_CRQ:
2376                         if (crq->status == PING)
2377                                 ibmvscsis_ping_response(vscsi);
2378                         break;
2379
2380                 default:
2381                         dev_err(&vscsi->dev, "parse_command: invalid format %d\n",
2382                                 (uint)crq->format);
2383                         ibmvscsis_post_disconnect(vscsi,
2384                                                   ERR_DISCONNECT_RECONNECT, 0);
2385                         break;
2386                 }
2387                 break;
2388
2389         case VALID_TRANS_EVENT:
2390                 rc = ibmvscsis_trans_event(vscsi, crq);
2391                 break;
2392
2393         case VALID_INIT_MSG:
2394                 rc = ibmvscsis_init_msg(vscsi, crq);
2395                 break;
2396
2397         default:
2398                 dev_err(&vscsi->dev, "parse_command: invalid valid field %d\n",
2399                         (uint)crq->valid);
2400                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2401                 break;
2402         }
2403
2404         /*
2405          * Return only what the interrupt handler cares
2406          * about. Most errors we keep right on trucking.
2407          */
2408         rc = vscsi->flags & SCHEDULE_DISCONNECT;
2409
2410         return rc;
2411 }
2412
2413 static int read_dma_window(struct scsi_info *vscsi)
2414 {
2415         struct vio_dev *vdev = vscsi->dma_dev;
2416         const __be32 *dma_window;
2417         const __be32 *prop;
2418
2419         /* TODO Using of_parse_dma_window would be better, but it doesn't give
2420          * a way to read multiple windows without already knowing the size of
2421          * a window or the number of windows.
2422          */
2423         dma_window = (const __be32 *)vio_get_attribute(vdev,
2424                                                        "ibm,my-dma-window",
2425                                                        NULL);
2426         if (!dma_window) {
2427                 pr_err("Couldn't find ibm,my-dma-window property\n");
2428                 return -1;
2429         }
2430
2431         vscsi->dds.window[LOCAL].liobn = be32_to_cpu(*dma_window);
2432         dma_window++;
2433
2434         prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-address-cells",
2435                                                  NULL);
2436         if (!prop) {
2437                 pr_warn("Couldn't find ibm,#dma-address-cells property\n");
2438                 dma_window++;
2439         } else {
2440                 dma_window += be32_to_cpu(*prop);
2441         }
2442
2443         prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-size-cells",
2444                                                  NULL);
2445         if (!prop) {
2446                 pr_warn("Couldn't find ibm,#dma-size-cells property\n");
2447                 dma_window++;
2448         } else {
2449                 dma_window += be32_to_cpu(*prop);
2450         }
2451
2452         /* dma_window should point to the second window now */
2453         vscsi->dds.window[REMOTE].liobn = be32_to_cpu(*dma_window);
2454
2455         return 0;
2456 }
2457
2458 static struct ibmvscsis_tport *ibmvscsis_lookup_port(const char *name)
2459 {
2460         struct ibmvscsis_tport *tport = NULL;
2461         struct vio_dev *vdev;
2462         struct scsi_info *vscsi;
2463
2464         spin_lock_bh(&ibmvscsis_dev_lock);
2465         list_for_each_entry(vscsi, &ibmvscsis_dev_list, list) {
2466                 vdev = vscsi->dma_dev;
2467                 if (!strcmp(dev_name(&vdev->dev), name)) {
2468                         tport = &vscsi->tport;
2469                         break;
2470                 }
2471         }
2472         spin_unlock_bh(&ibmvscsis_dev_lock);
2473
2474         return tport;
2475 }
2476
2477 /**
2478  * ibmvscsis_parse_cmd() - Parse SRP Command
2479  * @vscsi:      Pointer to our adapter structure
2480  * @cmd:        Pointer to command element with SRP command
2481  *
2482  * Parse the srp command; if it is valid then submit it to tcm.
2483  * Note: The return code does not reflect the status of the SCSI CDB.
2484  *
2485  * EXECUTION ENVIRONMENT:
2486  *      Process level
2487  */
2488 static void ibmvscsis_parse_cmd(struct scsi_info *vscsi,
2489                                 struct ibmvscsis_cmd *cmd)
2490 {
2491         struct iu_entry *iue = cmd->iue;
2492         struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
2493         struct ibmvscsis_nexus *nexus;
2494         u64 data_len = 0;
2495         enum dma_data_direction dir;
2496         int attr = 0;
2497         int rc = 0;
2498
2499         nexus = vscsi->tport.ibmv_nexus;
2500         /*
2501          * additional length in bytes.  Note that the SRP spec says that
2502          * additional length is in 4-byte words, but technically the
2503          * additional length field is only the upper 6 bits of the byte.
2504          * The lower 2 bits are reserved.  If the lower 2 bits are 0 (as
2505          * all reserved fields should be), then interpreting the byte as
2506          * an int will yield the length in bytes.
2507          */
2508         if (srp->add_cdb_len & 0x03) {
2509                 dev_err(&vscsi->dev, "parse_cmd: reserved bits set in IU\n");
2510                 spin_lock_bh(&vscsi->intr_lock);
2511                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2512                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2513                 spin_unlock_bh(&vscsi->intr_lock);
2514                 return;
2515         }
2516
2517         if (srp_get_desc_table(srp, &dir, &data_len)) {
2518                 dev_err(&vscsi->dev, "0x%llx: parsing SRP descriptor table failed.\n",
2519                         srp->tag);
2520                 goto fail;
2521         }
2522
2523         cmd->rsp.sol_not = srp->sol_not;
2524
2525         switch (srp->task_attr) {
2526         case SRP_SIMPLE_TASK:
2527                 attr = TCM_SIMPLE_TAG;
2528                 break;
2529         case SRP_ORDERED_TASK:
2530                 attr = TCM_ORDERED_TAG;
2531                 break;
2532         case SRP_HEAD_TASK:
2533                 attr = TCM_HEAD_TAG;
2534                 break;
2535         case SRP_ACA_TASK:
2536                 attr = TCM_ACA_TAG;
2537                 break;
2538         default:
2539                 dev_err(&vscsi->dev, "Invalid task attribute %d\n",
2540                         srp->task_attr);
2541                 goto fail;
2542         }
2543
2544         cmd->se_cmd.tag = be64_to_cpu(srp->tag);
2545
2546         spin_lock_bh(&vscsi->intr_lock);
2547         list_add_tail(&cmd->list, &vscsi->active_q);
2548         spin_unlock_bh(&vscsi->intr_lock);
2549
2550         srp->lun.scsi_lun[0] &= 0x3f;
2551
2552         rc = target_submit_cmd(&cmd->se_cmd, nexus->se_sess, srp->cdb,
2553                                cmd->sense_buf, scsilun_to_int(&srp->lun),
2554                                data_len, attr, dir, 0);
2555         if (rc) {
2556                 dev_err(&vscsi->dev, "target_submit_cmd failed, rc %d\n", rc);
2557                 spin_lock_bh(&vscsi->intr_lock);
2558                 list_del(&cmd->list);
2559                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2560                 spin_unlock_bh(&vscsi->intr_lock);
2561                 goto fail;
2562         }
2563         return;
2564
2565 fail:
2566         spin_lock_bh(&vscsi->intr_lock);
2567         ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2568         spin_unlock_bh(&vscsi->intr_lock);
2569 }
2570
2571 /**
2572  * ibmvscsis_parse_task() - Parse SRP Task Management Request
2573  * @vscsi:      Pointer to our adapter structure
2574  * @cmd:        Pointer to command element with SRP task management request
2575  *
2576  * Parse the srp task management request; if it is valid then submit it to tcm.
2577  * Note: The return code does not reflect the status of the task management
2578  * request.
2579  *
2580  * EXECUTION ENVIRONMENT:
2581  *      Processor level
2582  */
2583 static void ibmvscsis_parse_task(struct scsi_info *vscsi,
2584                                  struct ibmvscsis_cmd *cmd)
2585 {
2586         struct iu_entry *iue = cmd->iue;
2587         struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
2588         int tcm_type;
2589         u64 tag_to_abort = 0;
2590         int rc = 0;
2591         struct ibmvscsis_nexus *nexus;
2592
2593         nexus = vscsi->tport.ibmv_nexus;
2594
2595         cmd->rsp.sol_not = srp_tsk->sol_not;
2596
2597         switch (srp_tsk->tsk_mgmt_func) {
2598         case SRP_TSK_ABORT_TASK:
2599                 tcm_type = TMR_ABORT_TASK;
2600                 tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
2601                 break;
2602         case SRP_TSK_ABORT_TASK_SET:
2603                 tcm_type = TMR_ABORT_TASK_SET;
2604                 break;
2605         case SRP_TSK_CLEAR_TASK_SET:
2606                 tcm_type = TMR_CLEAR_TASK_SET;
2607                 break;
2608         case SRP_TSK_LUN_RESET:
2609                 tcm_type = TMR_LUN_RESET;
2610                 break;
2611         case SRP_TSK_CLEAR_ACA:
2612                 tcm_type = TMR_CLEAR_ACA;
2613                 break;
2614         default:
2615                 dev_err(&vscsi->dev, "unknown task mgmt func %d\n",
2616                         srp_tsk->tsk_mgmt_func);
2617                 cmd->se_cmd.se_tmr_req->response =
2618                         TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2619                 rc = -1;
2620                 break;
2621         }
2622
2623         if (!rc) {
2624                 cmd->se_cmd.tag = be64_to_cpu(srp_tsk->tag);
2625
2626                 spin_lock_bh(&vscsi->intr_lock);
2627                 list_add_tail(&cmd->list, &vscsi->active_q);
2628                 spin_unlock_bh(&vscsi->intr_lock);
2629
2630                 srp_tsk->lun.scsi_lun[0] &= 0x3f;
2631
2632                 pr_debug("calling submit_tmr, func %d\n",
2633                          srp_tsk->tsk_mgmt_func);
2634                 rc = target_submit_tmr(&cmd->se_cmd, nexus->se_sess, NULL,
2635                                        scsilun_to_int(&srp_tsk->lun), srp_tsk,
2636                                        tcm_type, GFP_KERNEL, tag_to_abort, 0);
2637                 if (rc) {
2638                         dev_err(&vscsi->dev, "target_submit_tmr failed, rc %d\n",
2639                                 rc);
2640                         spin_lock_bh(&vscsi->intr_lock);
2641                         list_del(&cmd->list);
2642                         spin_unlock_bh(&vscsi->intr_lock);
2643                         cmd->se_cmd.se_tmr_req->response =
2644                                 TMR_FUNCTION_REJECTED;
2645                 }
2646         }
2647
2648         if (rc)
2649                 transport_send_check_condition_and_sense(&cmd->se_cmd, 0, 0);
2650 }
2651
2652 static void ibmvscsis_scheduler(struct work_struct *work)
2653 {
2654         struct ibmvscsis_cmd *cmd = container_of(work, struct ibmvscsis_cmd,
2655                                                  work);
2656         struct scsi_info *vscsi = cmd->adapter;
2657
2658         spin_lock_bh(&vscsi->intr_lock);
2659
2660         /* Remove from schedule_q */
2661         list_del(&cmd->list);
2662
2663         /* Don't submit cmd if we're disconnecting */
2664         if (vscsi->flags & (SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED)) {
2665                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2666
2667                 /* ibmvscsis_disconnect might be waiting for us */
2668                 if (list_empty(&vscsi->active_q) &&
2669                     list_empty(&vscsi->schedule_q) &&
2670                     (vscsi->flags & WAIT_FOR_IDLE)) {
2671                         vscsi->flags &= ~WAIT_FOR_IDLE;
2672                         complete(&vscsi->wait_idle);
2673                 }
2674
2675                 spin_unlock_bh(&vscsi->intr_lock);
2676                 return;
2677         }
2678
2679         spin_unlock_bh(&vscsi->intr_lock);
2680
2681         switch (cmd->type) {
2682         case SCSI_CDB:
2683                 ibmvscsis_parse_cmd(vscsi, cmd);
2684                 break;
2685         case TASK_MANAGEMENT:
2686                 ibmvscsis_parse_task(vscsi, cmd);
2687                 break;
2688         default:
2689                 dev_err(&vscsi->dev, "scheduler, invalid cmd type %d\n",
2690                         cmd->type);
2691                 spin_lock_bh(&vscsi->intr_lock);
2692                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2693                 spin_unlock_bh(&vscsi->intr_lock);
2694                 break;
2695         }
2696 }
2697
2698 static int ibmvscsis_alloc_cmds(struct scsi_info *vscsi, int num)
2699 {
2700         struct ibmvscsis_cmd *cmd;
2701         int i;
2702
2703         INIT_LIST_HEAD(&vscsi->free_cmd);
2704         vscsi->cmd_pool = kcalloc(num, sizeof(struct ibmvscsis_cmd),
2705                                   GFP_KERNEL);
2706         if (!vscsi->cmd_pool)
2707                 return -ENOMEM;
2708
2709         for (i = 0, cmd = (struct ibmvscsis_cmd *)vscsi->cmd_pool; i < num;
2710              i++, cmd++) {
2711                 cmd->adapter = vscsi;
2712                 INIT_WORK(&cmd->work, ibmvscsis_scheduler);
2713                 list_add_tail(&cmd->list, &vscsi->free_cmd);
2714         }
2715
2716         return 0;
2717 }
2718
2719 static void ibmvscsis_free_cmds(struct scsi_info *vscsi)
2720 {
2721         kfree(vscsi->cmd_pool);
2722         vscsi->cmd_pool = NULL;
2723         INIT_LIST_HEAD(&vscsi->free_cmd);
2724 }
2725
2726 /**
2727  * ibmvscsis_service_wait_q() - Service Waiting Queue
2728  * @timer:      Pointer to timer which has expired
2729  *
2730  * This routine is called when the timer pops to service the waiting
2731  * queue. Elements on the queue have completed, their responses have been
2732  * copied to the client, but the client's response queue was full so
2733  * the queue message could not be sent. The routine grabs the proper locks
2734  * and calls send messages.
2735  *
2736  * EXECUTION ENVIRONMENT:
2737  *      called at interrupt level
2738  */
2739 static enum hrtimer_restart ibmvscsis_service_wait_q(struct hrtimer *timer)
2740 {
2741         struct timer_cb *p_timer = container_of(timer, struct timer_cb, timer);
2742         struct scsi_info *vscsi = container_of(p_timer, struct scsi_info,
2743                                                rsp_q_timer);
2744
2745         spin_lock_bh(&vscsi->intr_lock);
2746         p_timer->timer_pops += 1;
2747         p_timer->started = false;
2748         ibmvscsis_send_messages(vscsi);
2749         spin_unlock_bh(&vscsi->intr_lock);
2750
2751         return HRTIMER_NORESTART;
2752 }
2753
2754 static long ibmvscsis_alloctimer(struct scsi_info *vscsi)
2755 {
2756         struct timer_cb *p_timer;
2757
2758         p_timer = &vscsi->rsp_q_timer;
2759         hrtimer_init(&p_timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
2760
2761         p_timer->timer.function = ibmvscsis_service_wait_q;
2762         p_timer->started = false;
2763         p_timer->timer_pops = 0;
2764
2765         return ADAPT_SUCCESS;
2766 }
2767
2768 static void ibmvscsis_freetimer(struct scsi_info *vscsi)
2769 {
2770         struct timer_cb *p_timer;
2771
2772         p_timer = &vscsi->rsp_q_timer;
2773
2774         (void)hrtimer_cancel(&p_timer->timer);
2775
2776         p_timer->started = false;
2777         p_timer->timer_pops = 0;
2778 }
2779
2780 static irqreturn_t ibmvscsis_interrupt(int dummy, void *data)
2781 {
2782         struct scsi_info *vscsi = data;
2783
2784         vio_disable_interrupts(vscsi->dma_dev);
2785         tasklet_schedule(&vscsi->work_task);
2786
2787         return IRQ_HANDLED;
2788 }
2789
2790 /**
2791  * ibmvscsis_enable_change_state() - Set new state based on enabled status
2792  * @vscsi:      Pointer to our adapter structure
2793  *
2794  * This function determines our new state now that we are enabled.  This
2795  * may involve sending an Init Complete message to the client.
2796  *
2797  * Must be called with interrupt lock held.
2798  */
2799 static long ibmvscsis_enable_change_state(struct scsi_info *vscsi)
2800 {
2801         int bytes;
2802         long rc = ADAPT_SUCCESS;
2803
2804         bytes = vscsi->cmd_q.size * PAGE_SIZE;
2805         rc = h_reg_crq(vscsi->dds.unit_id, vscsi->cmd_q.crq_token, bytes);
2806         if (rc == H_CLOSED || rc == H_SUCCESS) {
2807                 vscsi->state = WAIT_CONNECTION;
2808                 rc = ibmvscsis_establish_new_q(vscsi);
2809         }
2810
2811         if (rc != ADAPT_SUCCESS) {
2812                 vscsi->state = ERR_DISCONNECTED;
2813                 vscsi->flags |= RESPONSE_Q_DOWN;
2814         }
2815
2816         return rc;
2817 }
2818
2819 /**
2820  * ibmvscsis_create_command_q() - Create Command Queue
2821  * @vscsi:      Pointer to our adapter structure
2822  * @num_cmds:   Currently unused.  In the future, may be used to determine
2823  *              the size of the CRQ.
2824  *
2825  * Allocates memory for command queue maps remote memory into an ioba
2826  * initializes the command response queue
2827  *
2828  * EXECUTION ENVIRONMENT:
2829  *      Process level only
2830  */
2831 static long ibmvscsis_create_command_q(struct scsi_info *vscsi, int num_cmds)
2832 {
2833         int pages;
2834         struct vio_dev *vdev = vscsi->dma_dev;
2835
2836         /* We might support multiple pages in the future, but just 1 for now */
2837         pages = 1;
2838
2839         vscsi->cmd_q.size = pages;
2840
2841         vscsi->cmd_q.base_addr =
2842                 (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
2843         if (!vscsi->cmd_q.base_addr)
2844                 return -ENOMEM;
2845
2846         vscsi->cmd_q.mask = ((uint)pages * CRQ_PER_PAGE) - 1;
2847
2848         vscsi->cmd_q.crq_token = dma_map_single(&vdev->dev,
2849                                                 vscsi->cmd_q.base_addr,
2850                                                 PAGE_SIZE, DMA_BIDIRECTIONAL);
2851         if (dma_mapping_error(&vdev->dev, vscsi->cmd_q.crq_token)) {
2852                 free_page((unsigned long)vscsi->cmd_q.base_addr);
2853                 return -ENOMEM;
2854         }
2855
2856         return 0;
2857 }
2858
2859 /**
2860  * ibmvscsis_destroy_command_q - Destroy Command Queue
2861  * @vscsi:      Pointer to our adapter structure
2862  *
2863  * Releases memory for command queue and unmaps mapped remote memory.
2864  *
2865  * EXECUTION ENVIRONMENT:
2866  *      Process level only
2867  */
2868 static void ibmvscsis_destroy_command_q(struct scsi_info *vscsi)
2869 {
2870         dma_unmap_single(&vscsi->dma_dev->dev, vscsi->cmd_q.crq_token,
2871                          PAGE_SIZE, DMA_BIDIRECTIONAL);
2872         free_page((unsigned long)vscsi->cmd_q.base_addr);
2873         vscsi->cmd_q.base_addr = NULL;
2874         vscsi->state = NO_QUEUE;
2875 }
2876
2877 static u8 ibmvscsis_fast_fail(struct scsi_info *vscsi,
2878                               struct ibmvscsis_cmd *cmd)
2879 {
2880         struct iu_entry *iue = cmd->iue;
2881         struct se_cmd *se_cmd = &cmd->se_cmd;
2882         struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
2883         struct scsi_sense_hdr sshdr;
2884         u8 rc = se_cmd->scsi_status;
2885
2886         if (vscsi->fast_fail && (READ_CMD(srp->cdb) || WRITE_CMD(srp->cdb)))
2887                 if (scsi_normalize_sense(se_cmd->sense_buffer,
2888                                          se_cmd->scsi_sense_length, &sshdr))
2889                         if (sshdr.sense_key == HARDWARE_ERROR &&
2890                             (se_cmd->residual_count == 0 ||
2891                              se_cmd->residual_count == se_cmd->data_length)) {
2892                                 rc = NO_SENSE;
2893                                 cmd->flags |= CMD_FAST_FAIL;
2894                         }
2895
2896         return rc;
2897 }
2898
2899 /**
2900  * srp_build_response() - Build an SRP response buffer
2901  * @vscsi:      Pointer to our adapter structure
2902  * @cmd:        Pointer to command for which to send the response
2903  * @len_p:      Where to return the length of the IU response sent.  This
2904  *              is needed to construct the CRQ response.
2905  *
2906  * Build the SRP response buffer and copy it to the client's memory space.
2907  */
2908 static long srp_build_response(struct scsi_info *vscsi,
2909                                struct ibmvscsis_cmd *cmd, uint *len_p)
2910 {
2911         struct iu_entry *iue = cmd->iue;
2912         struct se_cmd *se_cmd = &cmd->se_cmd;
2913         struct srp_rsp *rsp;
2914         uint len;
2915         u32 rsp_code;
2916         char *data;
2917         u32 *tsk_status;
2918         long rc = ADAPT_SUCCESS;
2919
2920         spin_lock_bh(&vscsi->intr_lock);
2921
2922         rsp = &vio_iu(iue)->srp.rsp;
2923         len = sizeof(*rsp);
2924         memset(rsp, 0, len);
2925         data = rsp->data;
2926
2927         rsp->opcode = SRP_RSP;
2928
2929         if (vscsi->credit > 0 && vscsi->state == SRP_PROCESSING)
2930                 rsp->req_lim_delta = cpu_to_be32(vscsi->credit);
2931         else
2932                 rsp->req_lim_delta = cpu_to_be32(1 + vscsi->credit);
2933         rsp->tag = cmd->rsp.tag;
2934         rsp->flags = 0;
2935
2936         if (cmd->type == SCSI_CDB) {
2937                 rsp->status = ibmvscsis_fast_fail(vscsi, cmd);
2938                 if (rsp->status) {
2939                         pr_debug("build_resp: cmd %p, scsi status %d\n", cmd,
2940                                  (int)rsp->status);
2941                         ibmvscsis_determine_resid(se_cmd, rsp);
2942                         if (se_cmd->scsi_sense_length && se_cmd->sense_buffer) {
2943                                 rsp->sense_data_len =
2944                                         cpu_to_be32(se_cmd->scsi_sense_length);
2945                                 rsp->flags |= SRP_RSP_FLAG_SNSVALID;
2946                                 len += se_cmd->scsi_sense_length;
2947                                 memcpy(data, se_cmd->sense_buffer,
2948                                        se_cmd->scsi_sense_length);
2949                         }
2950                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
2951                                 UCSOLNT_RESP_SHIFT;
2952                 } else if (cmd->flags & CMD_FAST_FAIL) {
2953                         pr_debug("build_resp: cmd %p, fast fail\n", cmd);
2954                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
2955                                 UCSOLNT_RESP_SHIFT;
2956                 } else {
2957                         rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
2958                                 SCSOLNT_RESP_SHIFT;
2959                 }
2960         } else {
2961                 /* this is task management */
2962                 rsp->status = 0;
2963                 rsp->resp_data_len = cpu_to_be32(4);
2964                 rsp->flags |= SRP_RSP_FLAG_RSPVALID;
2965
2966                 switch (se_cmd->se_tmr_req->response) {
2967                 case TMR_FUNCTION_COMPLETE:
2968                 case TMR_TASK_DOES_NOT_EXIST:
2969                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_COMPLETE;
2970                         rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
2971                                 SCSOLNT_RESP_SHIFT;
2972                         break;
2973                 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
2974                 case TMR_LUN_DOES_NOT_EXIST:
2975                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_NOT_SUPPORTED;
2976                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
2977                                 UCSOLNT_RESP_SHIFT;
2978                         break;
2979                 case TMR_FUNCTION_FAILED:
2980                 case TMR_FUNCTION_REJECTED:
2981                 default:
2982                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_FAILED;
2983                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
2984                                 UCSOLNT_RESP_SHIFT;
2985                         break;
2986                 }
2987
2988                 tsk_status = (u32 *)data;
2989                 *tsk_status = cpu_to_be32(rsp_code);
2990                 data = (char *)(tsk_status + 1);
2991                 len += 4;
2992         }
2993
2994         dma_wmb();
2995         rc = h_copy_rdma(len, vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
2996                          vscsi->dds.window[REMOTE].liobn,
2997                          be64_to_cpu(iue->remote_token));
2998
2999         switch (rc) {
3000         case H_SUCCESS:
3001                 vscsi->credit = 0;
3002                 *len_p = len;
3003                 break;
3004         case H_PERMISSION:
3005                 if (connection_broken(vscsi))
3006                         vscsi->flags |= RESPONSE_Q_DOWN | CLIENT_FAILED;
3007
3008                 dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld, flags 0x%x, state 0x%hx\n",
3009                         rc, vscsi->flags, vscsi->state);
3010                 break;
3011         case H_SOURCE_PARM:
3012         case H_DEST_PARM:
3013         default:
3014                 dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld\n",
3015                         rc);
3016                 break;
3017         }
3018
3019         spin_unlock_bh(&vscsi->intr_lock);
3020
3021         return rc;
3022 }
3023
3024 static int ibmvscsis_rdma(struct ibmvscsis_cmd *cmd, struct scatterlist *sg,
3025                           int nsg, struct srp_direct_buf *md, int nmd,
3026                           enum dma_data_direction dir, unsigned int bytes)
3027 {
3028         struct iu_entry *iue = cmd->iue;
3029         struct srp_target *target = iue->target;
3030         struct scsi_info *vscsi = target->ldata;
3031         struct scatterlist *sgp;
3032         dma_addr_t client_ioba, server_ioba;
3033         ulong buf_len;
3034         ulong client_len, server_len;
3035         int md_idx;
3036         long tx_len;
3037         long rc = 0;
3038
3039         if (bytes == 0)
3040                 return 0;
3041
3042         sgp = sg;
3043         client_len = 0;
3044         server_len = 0;
3045         md_idx = 0;
3046         tx_len = bytes;
3047
3048         do {
3049                 if (client_len == 0) {
3050                         if (md_idx >= nmd) {
3051                                 dev_err(&vscsi->dev, "rdma: ran out of client memory descriptors\n");
3052                                 rc = -EIO;
3053                                 break;
3054                         }
3055                         client_ioba = be64_to_cpu(md[md_idx].va);
3056                         client_len = be32_to_cpu(md[md_idx].len);
3057                 }
3058                 if (server_len == 0) {
3059                         if (!sgp) {
3060                                 dev_err(&vscsi->dev, "rdma: ran out of scatter/gather list\n");
3061                                 rc = -EIO;
3062                                 break;
3063                         }
3064                         server_ioba = sg_dma_address(sgp);
3065                         server_len = sg_dma_len(sgp);
3066                 }
3067
3068                 buf_len = tx_len;
3069
3070                 if (buf_len > client_len)
3071                         buf_len = client_len;
3072
3073                 if (buf_len > server_len)
3074                         buf_len = server_len;
3075
3076                 if (buf_len > max_vdma_size)
3077                         buf_len = max_vdma_size;
3078
3079                 if (dir == DMA_TO_DEVICE) {
3080                         /* read from client */
3081                         rc = h_copy_rdma(buf_len,
3082                                          vscsi->dds.window[REMOTE].liobn,
3083                                          client_ioba,
3084                                          vscsi->dds.window[LOCAL].liobn,
3085                                          server_ioba);
3086                 } else {
3087                         /* The h_copy_rdma will cause phyp, running in another
3088                          * partition, to read memory, so we need to make sure
3089                          * the data has been written out, hence these syncs.
3090                          */
3091                         /* ensure that everything is in memory */
3092                         isync();
3093                         /* ensure that memory has been made visible */
3094                         dma_wmb();
3095                         rc = h_copy_rdma(buf_len,
3096                                          vscsi->dds.window[LOCAL].liobn,
3097                                          server_ioba,
3098                                          vscsi->dds.window[REMOTE].liobn,
3099                                          client_ioba);
3100                 }
3101                 switch (rc) {
3102                 case H_SUCCESS:
3103                         break;
3104                 case H_PERMISSION:
3105                 case H_SOURCE_PARM:
3106                 case H_DEST_PARM:
3107                         if (connection_broken(vscsi)) {
3108                                 spin_lock_bh(&vscsi->intr_lock);
3109                                 vscsi->flags |=
3110                                         (RESPONSE_Q_DOWN | CLIENT_FAILED);
3111                                 spin_unlock_bh(&vscsi->intr_lock);
3112                         }
3113                         dev_err(&vscsi->dev, "rdma: h_copy_rdma failed, rc %ld\n",
3114                                 rc);
3115                         break;
3116
3117                 default:
3118                         dev_err(&vscsi->dev, "rdma: unknown error %ld from h_copy_rdma\n",
3119                                 rc);
3120                         break;
3121                 }
3122
3123                 if (!rc) {
3124                         tx_len -= buf_len;
3125                         if (tx_len) {
3126                                 client_len -= buf_len;
3127                                 if (client_len == 0)
3128                                         md_idx++;
3129                                 else
3130                                         client_ioba += buf_len;
3131
3132                                 server_len -= buf_len;
3133                                 if (server_len == 0)
3134                                         sgp = sg_next(sgp);
3135                                 else
3136                                         server_ioba += buf_len;
3137                         } else {
3138                                 break;
3139                         }
3140                 }
3141         } while (!rc);
3142
3143         return rc;
3144 }
3145
3146 /**
3147  * ibmvscsis_handle_crq() - Handle CRQ
3148  * @data:       Pointer to our adapter structure
3149  *
3150  * Read the command elements from the command queue and copy the payloads
3151  * associated with the command elements to local memory and execute the
3152  * SRP requests.
3153  *
3154  * Note: this is an edge triggered interrupt. It can not be shared.
3155  */
3156 static void ibmvscsis_handle_crq(unsigned long data)
3157 {
3158         struct scsi_info *vscsi = (struct scsi_info *)data;
3159         struct viosrp_crq *crq;
3160         long rc;
3161         bool ack = true;
3162         volatile u8 valid;
3163
3164         spin_lock_bh(&vscsi->intr_lock);
3165
3166         pr_debug("got interrupt\n");
3167
3168         /*
3169          * if we are in a path where we are waiting for all pending commands
3170          * to complete because we received a transport event and anything in
3171          * the command queue is for a new connection, do nothing
3172          */
3173         if (TARGET_STOP(vscsi)) {
3174                 vio_enable_interrupts(vscsi->dma_dev);
3175
3176                 pr_debug("handle_crq, don't process: flags 0x%x, state 0x%hx\n",
3177                          vscsi->flags, vscsi->state);
3178                 spin_unlock_bh(&vscsi->intr_lock);
3179                 return;
3180         }
3181
3182         rc = vscsi->flags & SCHEDULE_DISCONNECT;
3183         crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
3184         valid = crq->valid;
3185         dma_rmb();
3186
3187         while (valid) {
3188                 /*
3189                  * These are edege triggered interrupts. After dropping out of
3190                  * the while loop, the code must check for work since an
3191                  * interrupt could be lost, and an elment be left on the queue,
3192                  * hence the label.
3193                  */
3194 cmd_work:
3195                 vscsi->cmd_q.index =
3196                         (vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
3197
3198                 if (!rc) {
3199                         rc = ibmvscsis_parse_command(vscsi, crq);
3200                 } else {
3201                         if ((uint)crq->valid == VALID_TRANS_EVENT) {
3202                                 /*
3203                                  * must service the transport layer events even
3204                                  * in an error state, dont break out until all
3205                                  * the consecutive transport events have been
3206                                  * processed
3207                                  */
3208                                 rc = ibmvscsis_trans_event(vscsi, crq);
3209                         } else if (vscsi->flags & TRANS_EVENT) {
3210                                 /*
3211                                  * if a transport event has occurred leave
3212                                  * everything but transport events on the queue
3213                                  *
3214                                  * need to decrement the queue index so we can
3215                                  * look at the element again
3216                                  */
3217                                 if (vscsi->cmd_q.index)
3218                                         vscsi->cmd_q.index -= 1;
3219                                 else
3220                                         /*
3221                                          * index is at 0 it just wrapped.
3222                                          * have it index last element in q
3223                                          */
3224                                         vscsi->cmd_q.index = vscsi->cmd_q.mask;
3225                                 break;
3226                         }
3227                 }
3228
3229                 crq->valid = INVALIDATE_CMD_RESP_EL;
3230
3231                 crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
3232                 valid = crq->valid;
3233                 dma_rmb();
3234         }
3235
3236         if (!rc) {
3237                 if (ack) {
3238                         vio_enable_interrupts(vscsi->dma_dev);
3239                         ack = false;
3240                         pr_debug("handle_crq, reenabling interrupts\n");
3241                 }
3242                 valid = crq->valid;
3243                 dma_rmb();
3244                 if (valid)
3245                         goto cmd_work;
3246         } else {
3247                 pr_debug("handle_crq, error: flags 0x%x, state 0x%hx, crq index 0x%x\n",
3248                          vscsi->flags, vscsi->state, vscsi->cmd_q.index);
3249         }
3250
3251         pr_debug("Leaving handle_crq: schedule_q empty %d, flags 0x%x, state 0x%hx\n",
3252                  (int)list_empty(&vscsi->schedule_q), vscsi->flags,
3253                  vscsi->state);
3254
3255         spin_unlock_bh(&vscsi->intr_lock);
3256 }
3257
3258 static int ibmvscsis_probe(struct vio_dev *vdev,
3259                            const struct vio_device_id *id)
3260 {
3261         struct scsi_info *vscsi;
3262         int rc = 0;
3263         long hrc = 0;
3264         char wq_name[24];
3265
3266         vscsi = kzalloc(sizeof(*vscsi), GFP_KERNEL);
3267         if (!vscsi) {
3268                 rc = -ENOMEM;
3269                 pr_err("probe: allocation of adapter failed\n");
3270                 return rc;
3271         }
3272
3273         vscsi->dma_dev = vdev;
3274         vscsi->dev = vdev->dev;
3275         INIT_LIST_HEAD(&vscsi->schedule_q);
3276         INIT_LIST_HEAD(&vscsi->waiting_rsp);
3277         INIT_LIST_HEAD(&vscsi->active_q);
3278
3279         snprintf(vscsi->tport.tport_name, IBMVSCSIS_NAMELEN, "%s",
3280                  dev_name(&vdev->dev));
3281
3282         pr_debug("probe tport_name: %s\n", vscsi->tport.tport_name);
3283
3284         rc = read_dma_window(vscsi);
3285         if (rc)
3286                 goto free_adapter;
3287         pr_debug("Probe: liobn 0x%x, riobn 0x%x\n",
3288                  vscsi->dds.window[LOCAL].liobn,
3289                  vscsi->dds.window[REMOTE].liobn);
3290
3291         strcpy(vscsi->eye, "VSCSI ");
3292         strncat(vscsi->eye, vdev->name, MAX_EYE);
3293
3294         vscsi->dds.unit_id = vdev->unit_address;
3295         strncpy(vscsi->dds.partition_name, partition_name,
3296                 sizeof(vscsi->dds.partition_name));
3297         vscsi->dds.partition_num = partition_number;
3298
3299         spin_lock_bh(&ibmvscsis_dev_lock);
3300         list_add_tail(&vscsi->list, &ibmvscsis_dev_list);
3301         spin_unlock_bh(&ibmvscsis_dev_lock);
3302
3303         /*
3304          * TBD: How do we determine # of cmds to request?  Do we know how
3305          * many "children" we have?
3306          */
3307         vscsi->request_limit = INITIAL_SRP_LIMIT;
3308         rc = srp_target_alloc(&vscsi->target, &vdev->dev, vscsi->request_limit,
3309                               SRP_MAX_IU_LEN);
3310         if (rc)
3311                 goto rem_list;
3312
3313         vscsi->target.ldata = vscsi;
3314
3315         rc = ibmvscsis_alloc_cmds(vscsi, vscsi->request_limit);
3316         if (rc) {
3317                 dev_err(&vscsi->dev, "alloc_cmds failed, rc %d, num %d\n",
3318                         rc, vscsi->request_limit);
3319                 goto free_target;
3320         }
3321
3322         /*
3323          * Note: the lock is used in freeing timers, so must initialize
3324          * first so that ordering in case of error is correct.
3325          */
3326         spin_lock_init(&vscsi->intr_lock);
3327
3328         rc = ibmvscsis_alloctimer(vscsi);
3329         if (rc) {
3330                 dev_err(&vscsi->dev, "probe: alloctimer failed, rc %d\n", rc);
3331                 goto free_cmds;
3332         }
3333
3334         rc = ibmvscsis_create_command_q(vscsi, 256);
3335         if (rc) {
3336                 dev_err(&vscsi->dev, "probe: create_command_q failed, rc %d\n",
3337                         rc);
3338                 goto free_timer;
3339         }
3340
3341         vscsi->map_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
3342         if (!vscsi->map_buf) {
3343                 rc = -ENOMEM;
3344                 dev_err(&vscsi->dev, "probe: allocating cmd buffer failed\n");
3345                 goto destroy_queue;
3346         }
3347
3348         vscsi->map_ioba = dma_map_single(&vdev->dev, vscsi->map_buf, PAGE_SIZE,
3349                                          DMA_BIDIRECTIONAL);
3350         if (dma_mapping_error(&vdev->dev, vscsi->map_ioba)) {
3351                 rc = -ENOMEM;
3352                 dev_err(&vscsi->dev, "probe: error mapping command buffer\n");
3353                 goto free_buf;
3354         }
3355
3356         hrc = h_vioctl(vscsi->dds.unit_id, H_GET_PARTNER_INFO,
3357                        (u64)vscsi->map_ioba | ((u64)PAGE_SIZE << 32), 0, 0, 0,
3358                        0);
3359         if (hrc == H_SUCCESS)
3360                 vscsi->client_data.partition_number =
3361                         be64_to_cpu(*(u64 *)vscsi->map_buf);
3362         /*
3363          * We expect the VIOCTL to fail if we're configured as "any
3364          * client can connect" and the client isn't activated yet.
3365          * We'll make the call again when he sends an init msg.
3366          */
3367         pr_debug("probe hrc %ld, client partition num %d\n",
3368                  hrc, vscsi->client_data.partition_number);
3369
3370         tasklet_init(&vscsi->work_task, ibmvscsis_handle_crq,
3371                      (unsigned long)vscsi);
3372
3373         init_completion(&vscsi->wait_idle);
3374         init_completion(&vscsi->unconfig);
3375
3376         snprintf(wq_name, 24, "ibmvscsis%s", dev_name(&vdev->dev));
3377         vscsi->work_q = create_workqueue(wq_name);
3378         if (!vscsi->work_q) {
3379                 rc = -ENOMEM;
3380                 dev_err(&vscsi->dev, "create_workqueue failed\n");
3381                 goto unmap_buf;
3382         }
3383
3384         rc = request_irq(vdev->irq, ibmvscsis_interrupt, 0, "ibmvscsis", vscsi);
3385         if (rc) {
3386                 rc = -EPERM;
3387                 dev_err(&vscsi->dev, "probe: request_irq failed, rc %d\n", rc);
3388                 goto destroy_WQ;
3389         }
3390
3391         vscsi->state = WAIT_ENABLED;
3392
3393         dev_set_drvdata(&vdev->dev, vscsi);
3394
3395         return 0;
3396
3397 destroy_WQ:
3398         destroy_workqueue(vscsi->work_q);
3399 unmap_buf:
3400         dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
3401                          DMA_BIDIRECTIONAL);
3402 free_buf:
3403         kfree(vscsi->map_buf);
3404 destroy_queue:
3405         tasklet_kill(&vscsi->work_task);
3406         ibmvscsis_unregister_command_q(vscsi);
3407         ibmvscsis_destroy_command_q(vscsi);
3408 free_timer:
3409         ibmvscsis_freetimer(vscsi);
3410 free_cmds:
3411         ibmvscsis_free_cmds(vscsi);
3412 free_target:
3413         srp_target_free(&vscsi->target);
3414 rem_list:
3415         spin_lock_bh(&ibmvscsis_dev_lock);
3416         list_del(&vscsi->list);
3417         spin_unlock_bh(&ibmvscsis_dev_lock);
3418 free_adapter:
3419         kfree(vscsi);
3420
3421         return rc;
3422 }
3423
3424 static int ibmvscsis_remove(struct vio_dev *vdev)
3425 {
3426         struct scsi_info *vscsi = dev_get_drvdata(&vdev->dev);
3427
3428         pr_debug("remove (%s)\n", dev_name(&vscsi->dma_dev->dev));
3429
3430         spin_lock_bh(&vscsi->intr_lock);
3431         ibmvscsis_post_disconnect(vscsi, UNCONFIGURING, 0);
3432         vscsi->flags |= CFG_SLEEPING;
3433         spin_unlock_bh(&vscsi->intr_lock);
3434         wait_for_completion(&vscsi->unconfig);
3435
3436         vio_disable_interrupts(vdev);
3437         free_irq(vdev->irq, vscsi);
3438         destroy_workqueue(vscsi->work_q);
3439         dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
3440                          DMA_BIDIRECTIONAL);
3441         kfree(vscsi->map_buf);
3442         tasklet_kill(&vscsi->work_task);
3443         ibmvscsis_destroy_command_q(vscsi);
3444         ibmvscsis_freetimer(vscsi);
3445         ibmvscsis_free_cmds(vscsi);
3446         srp_target_free(&vscsi->target);
3447         spin_lock_bh(&ibmvscsis_dev_lock);
3448         list_del(&vscsi->list);
3449         spin_unlock_bh(&ibmvscsis_dev_lock);
3450         kfree(vscsi);
3451
3452         return 0;
3453 }
3454
3455 static ssize_t system_id_show(struct device *dev,
3456                               struct device_attribute *attr, char *buf)
3457 {
3458         return snprintf(buf, PAGE_SIZE, "%s\n", system_id);
3459 }
3460
3461 static ssize_t partition_number_show(struct device *dev,
3462                                      struct device_attribute *attr, char *buf)
3463 {
3464         return snprintf(buf, PAGE_SIZE, "%x\n", partition_number);
3465 }
3466
3467 static ssize_t unit_address_show(struct device *dev,
3468                                  struct device_attribute *attr, char *buf)
3469 {
3470         struct scsi_info *vscsi = container_of(dev, struct scsi_info, dev);
3471
3472         return snprintf(buf, PAGE_SIZE, "%x\n", vscsi->dma_dev->unit_address);
3473 }
3474
3475 static int ibmvscsis_get_system_info(void)
3476 {
3477         struct device_node *rootdn, *vdevdn;
3478         const char *id, *model, *name;
3479         const uint *num;
3480
3481         rootdn = of_find_node_by_path("/");
3482         if (!rootdn)
3483                 return -ENOENT;
3484
3485         model = of_get_property(rootdn, "model", NULL);
3486         id = of_get_property(rootdn, "system-id", NULL);
3487         if (model && id)
3488                 snprintf(system_id, sizeof(system_id), "%s-%s", model, id);
3489
3490         name = of_get_property(rootdn, "ibm,partition-name", NULL);
3491         if (name)
3492                 strncpy(partition_name, name, sizeof(partition_name));
3493
3494         num = of_get_property(rootdn, "ibm,partition-no", NULL);
3495         if (num)
3496                 partition_number = of_read_number(num, 1);
3497
3498         of_node_put(rootdn);
3499
3500         vdevdn = of_find_node_by_path("/vdevice");
3501         if (vdevdn) {
3502                 const uint *mvds;
3503
3504                 mvds = of_get_property(vdevdn, "ibm,max-virtual-dma-size",
3505                                        NULL);
3506                 if (mvds)
3507                         max_vdma_size = *mvds;
3508                 of_node_put(vdevdn);
3509         }
3510
3511         return 0;
3512 }
3513
3514 static char *ibmvscsis_get_fabric_name(void)
3515 {
3516         return "ibmvscsis";
3517 }
3518
3519 static char *ibmvscsis_get_fabric_wwn(struct se_portal_group *se_tpg)
3520 {
3521         struct ibmvscsis_tport *tport =
3522                 container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
3523
3524         return tport->tport_name;
3525 }
3526
3527 static u16 ibmvscsis_get_tag(struct se_portal_group *se_tpg)
3528 {
3529         struct ibmvscsis_tport *tport =
3530                 container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
3531
3532         return tport->tport_tpgt;
3533 }
3534
3535 static u32 ibmvscsis_get_default_depth(struct se_portal_group *se_tpg)
3536 {
3537         return 1;
3538 }
3539
3540 static int ibmvscsis_check_true(struct se_portal_group *se_tpg)
3541 {
3542         return 1;
3543 }
3544
3545 static int ibmvscsis_check_false(struct se_portal_group *se_tpg)
3546 {
3547         return 0;
3548 }
3549
3550 static u32 ibmvscsis_tpg_get_inst_index(struct se_portal_group *se_tpg)
3551 {
3552         return 1;
3553 }
3554
3555 static int ibmvscsis_check_stop_free(struct se_cmd *se_cmd)
3556 {
3557         return target_put_sess_cmd(se_cmd);
3558 }
3559
3560 static void ibmvscsis_release_cmd(struct se_cmd *se_cmd)
3561 {
3562         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3563                                                  se_cmd);
3564         struct scsi_info *vscsi = cmd->adapter;
3565
3566         spin_lock_bh(&vscsi->intr_lock);
3567         /* Remove from active_q */
3568         list_move_tail(&cmd->list, &vscsi->waiting_rsp);
3569         ibmvscsis_send_messages(vscsi);
3570         spin_unlock_bh(&vscsi->intr_lock);
3571 }
3572
3573 static u32 ibmvscsis_sess_get_index(struct se_session *se_sess)
3574 {
3575         return 0;
3576 }
3577
3578 static int ibmvscsis_write_pending(struct se_cmd *se_cmd)
3579 {
3580         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3581                                                  se_cmd);
3582         struct iu_entry *iue = cmd->iue;
3583         int rc;
3584
3585         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma,
3586                                1, 1);
3587         if (rc) {
3588                 pr_err("srp_transfer_data() failed: %d\n", rc);
3589                 return -EIO;
3590         }
3591         /*
3592          * We now tell TCM to add this WRITE CDB directly into the TCM storage
3593          * object execution queue.
3594          */
3595         target_execute_cmd(se_cmd);
3596         return 0;
3597 }
3598
3599 static int ibmvscsis_write_pending_status(struct se_cmd *se_cmd)
3600 {
3601         return 0;
3602 }
3603
3604 static void ibmvscsis_set_default_node_attrs(struct se_node_acl *nacl)
3605 {
3606 }
3607
3608 static int ibmvscsis_get_cmd_state(struct se_cmd *se_cmd)
3609 {
3610         return 0;
3611 }
3612
3613 static int ibmvscsis_queue_data_in(struct se_cmd *se_cmd)
3614 {
3615         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3616                                                  se_cmd);
3617         struct iu_entry *iue = cmd->iue;
3618         struct scsi_info *vscsi = cmd->adapter;
3619         char *sd;
3620         uint len = 0;
3621         int rc;
3622
3623         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma, 1,
3624                                1);
3625         if (rc) {
3626                 pr_err("srp_transfer_data failed: %d\n", rc);
3627                 sd = se_cmd->sense_buffer;
3628                 se_cmd->scsi_sense_length = 18;
3629                 memset(se_cmd->sense_buffer, 0, se_cmd->scsi_sense_length);
3630                 /* Logical Unit Communication Time-out asc/ascq = 0x0801 */
3631                 scsi_build_sense_buffer(0, se_cmd->sense_buffer, MEDIUM_ERROR,
3632                                         0x08, 0x01);
3633         }
3634
3635         srp_build_response(vscsi, cmd, &len);
3636         cmd->rsp.format = SRP_FORMAT;
3637         cmd->rsp.len = len;
3638
3639         return 0;
3640 }
3641
3642 static int ibmvscsis_queue_status(struct se_cmd *se_cmd)
3643 {
3644         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3645                                                  se_cmd);
3646         struct scsi_info *vscsi = cmd->adapter;
3647         uint len;
3648
3649         pr_debug("queue_status %p\n", se_cmd);
3650
3651         srp_build_response(vscsi, cmd, &len);
3652         cmd->rsp.format = SRP_FORMAT;
3653         cmd->rsp.len = len;
3654
3655         return 0;
3656 }
3657
3658 static void ibmvscsis_queue_tm_rsp(struct se_cmd *se_cmd)
3659 {
3660         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3661                                                  se_cmd);
3662         struct scsi_info *vscsi = cmd->adapter;
3663         uint len;
3664
3665         pr_debug("queue_tm_rsp %p, status %d\n",
3666                  se_cmd, (int)se_cmd->se_tmr_req->response);
3667
3668         srp_build_response(vscsi, cmd, &len);
3669         cmd->rsp.format = SRP_FORMAT;
3670         cmd->rsp.len = len;
3671 }
3672
3673 static void ibmvscsis_aborted_task(struct se_cmd *se_cmd)
3674 {
3675         /* TBD: What (if anything) should we do here? */
3676         pr_debug("ibmvscsis_aborted_task %p\n", se_cmd);
3677 }
3678
3679 static struct se_wwn *ibmvscsis_make_tport(struct target_fabric_configfs *tf,
3680                                            struct config_group *group,
3681                                            const char *name)
3682 {
3683         struct ibmvscsis_tport *tport;
3684
3685         tport = ibmvscsis_lookup_port(name);
3686         if (tport) {
3687                 tport->tport_proto_id = SCSI_PROTOCOL_SRP;
3688                 pr_debug("make_tport(%s), pointer:%p, tport_id:%x\n",
3689                          name, tport, tport->tport_proto_id);
3690                 return &tport->tport_wwn;
3691         }
3692
3693         return ERR_PTR(-EINVAL);
3694 }
3695
3696 static void ibmvscsis_drop_tport(struct se_wwn *wwn)
3697 {
3698         struct ibmvscsis_tport *tport = container_of(wwn,
3699                                                      struct ibmvscsis_tport,
3700                                                      tport_wwn);
3701
3702         pr_debug("drop_tport(%s)\n",
3703                  config_item_name(&tport->tport_wwn.wwn_group.cg_item));
3704 }
3705
3706 static struct se_portal_group *ibmvscsis_make_tpg(struct se_wwn *wwn,
3707                                                   struct config_group *group,
3708                                                   const char *name)
3709 {
3710         struct ibmvscsis_tport *tport =
3711                 container_of(wwn, struct ibmvscsis_tport, tport_wwn);
3712         int rc;
3713
3714         tport->releasing = false;
3715
3716         rc = core_tpg_register(&tport->tport_wwn, &tport->se_tpg,
3717                                tport->tport_proto_id);
3718         if (rc)
3719                 return ERR_PTR(rc);
3720
3721         return &tport->se_tpg;
3722 }
3723
3724 static void ibmvscsis_drop_tpg(struct se_portal_group *se_tpg)
3725 {
3726         struct ibmvscsis_tport *tport = container_of(se_tpg,
3727                                                      struct ibmvscsis_tport,
3728                                                      se_tpg);
3729
3730         tport->releasing = true;
3731         tport->enabled = false;
3732
3733         /*
3734          * Release the virtual I_T Nexus for this ibmvscsis TPG
3735          */
3736         ibmvscsis_drop_nexus(tport);
3737         /*
3738          * Deregister the se_tpg from TCM..
3739          */
3740         core_tpg_deregister(se_tpg);
3741 }
3742
3743 static ssize_t ibmvscsis_wwn_version_show(struct config_item *item,
3744                                           char *page)
3745 {
3746         return scnprintf(page, PAGE_SIZE, "%s\n", IBMVSCSIS_VERSION);
3747 }
3748 CONFIGFS_ATTR_RO(ibmvscsis_wwn_, version);
3749
3750 static struct configfs_attribute *ibmvscsis_wwn_attrs[] = {
3751         &ibmvscsis_wwn_attr_version,
3752         NULL,
3753 };
3754
3755 static ssize_t ibmvscsis_tpg_enable_show(struct config_item *item,
3756                                          char *page)
3757 {
3758         struct se_portal_group *se_tpg = to_tpg(item);
3759         struct ibmvscsis_tport *tport = container_of(se_tpg,
3760                                                      struct ibmvscsis_tport,
3761                                                      se_tpg);
3762
3763         return snprintf(page, PAGE_SIZE, "%d\n", (tport->enabled) ? 1 : 0);
3764 }
3765
3766 static ssize_t ibmvscsis_tpg_enable_store(struct config_item *item,
3767                                           const char *page, size_t count)
3768 {
3769         struct se_portal_group *se_tpg = to_tpg(item);
3770         struct ibmvscsis_tport *tport = container_of(se_tpg,
3771                                                      struct ibmvscsis_tport,
3772                                                      se_tpg);
3773         struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
3774         unsigned long tmp;
3775         int rc;
3776         long lrc;
3777
3778         rc = kstrtoul(page, 0, &tmp);
3779         if (rc < 0) {
3780                 pr_err("Unable to extract srpt_tpg_store_enable\n");
3781                 return -EINVAL;
3782         }
3783
3784         if ((tmp != 0) && (tmp != 1)) {
3785                 pr_err("Illegal value for srpt_tpg_store_enable\n");
3786                 return -EINVAL;
3787         }
3788
3789         if (tmp) {
3790                 spin_lock_bh(&vscsi->intr_lock);
3791                 tport->enabled = true;
3792                 lrc = ibmvscsis_enable_change_state(vscsi);
3793                 if (lrc)
3794                         pr_err("enable_change_state failed, rc %ld state %d\n",
3795                                lrc, vscsi->state);
3796                 spin_unlock_bh(&vscsi->intr_lock);
3797         } else {
3798                 spin_lock_bh(&vscsi->intr_lock);
3799                 tport->enabled = false;
3800                 /* This simulates the server going down */
3801                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
3802                 spin_unlock_bh(&vscsi->intr_lock);
3803         }
3804
3805         pr_debug("tpg_enable_store, tmp %ld, state %d\n", tmp, vscsi->state);
3806
3807         return count;
3808 }
3809 CONFIGFS_ATTR(ibmvscsis_tpg_, enable);
3810
3811 static struct configfs_attribute *ibmvscsis_tpg_attrs[] = {
3812         &ibmvscsis_tpg_attr_enable,
3813         NULL,
3814 };
3815
3816 static const struct target_core_fabric_ops ibmvscsis_ops = {
3817         .module                         = THIS_MODULE,
3818         .name                           = "ibmvscsis",
3819         .max_data_sg_nents              = MAX_TXU / PAGE_SIZE,
3820         .get_fabric_name                = ibmvscsis_get_fabric_name,
3821         .tpg_get_wwn                    = ibmvscsis_get_fabric_wwn,
3822         .tpg_get_tag                    = ibmvscsis_get_tag,
3823         .tpg_get_default_depth          = ibmvscsis_get_default_depth,
3824         .tpg_check_demo_mode            = ibmvscsis_check_true,
3825         .tpg_check_demo_mode_cache      = ibmvscsis_check_true,
3826         .tpg_check_demo_mode_write_protect = ibmvscsis_check_false,
3827         .tpg_check_prod_mode_write_protect = ibmvscsis_check_false,
3828         .tpg_get_inst_index             = ibmvscsis_tpg_get_inst_index,
3829         .check_stop_free                = ibmvscsis_check_stop_free,
3830         .release_cmd                    = ibmvscsis_release_cmd,
3831         .sess_get_index                 = ibmvscsis_sess_get_index,
3832         .write_pending                  = ibmvscsis_write_pending,
3833         .write_pending_status           = ibmvscsis_write_pending_status,
3834         .set_default_node_attributes    = ibmvscsis_set_default_node_attrs,
3835         .get_cmd_state                  = ibmvscsis_get_cmd_state,
3836         .queue_data_in                  = ibmvscsis_queue_data_in,
3837         .queue_status                   = ibmvscsis_queue_status,
3838         .queue_tm_rsp                   = ibmvscsis_queue_tm_rsp,
3839         .aborted_task                   = ibmvscsis_aborted_task,
3840         /*
3841          * Setup function pointers for logic in target_core_fabric_configfs.c
3842          */
3843         .fabric_make_wwn                = ibmvscsis_make_tport,
3844         .fabric_drop_wwn                = ibmvscsis_drop_tport,
3845         .fabric_make_tpg                = ibmvscsis_make_tpg,
3846         .fabric_drop_tpg                = ibmvscsis_drop_tpg,
3847
3848         .tfc_wwn_attrs                  = ibmvscsis_wwn_attrs,
3849         .tfc_tpg_base_attrs             = ibmvscsis_tpg_attrs,
3850 };
3851
3852 static void ibmvscsis_dev_release(struct device *dev) {};
3853
3854 static struct class_attribute ibmvscsis_class_attrs[] = {
3855         __ATTR_NULL,
3856 };
3857
3858 static struct device_attribute dev_attr_system_id =
3859         __ATTR(system_id, S_IRUGO, system_id_show, NULL);
3860
3861 static struct device_attribute dev_attr_partition_number =
3862         __ATTR(partition_number, S_IRUGO, partition_number_show, NULL);
3863
3864 static struct device_attribute dev_attr_unit_address =
3865         __ATTR(unit_address, S_IRUGO, unit_address_show, NULL);
3866
3867 static struct attribute *ibmvscsis_dev_attrs[] = {
3868         &dev_attr_system_id.attr,
3869         &dev_attr_partition_number.attr,
3870         &dev_attr_unit_address.attr,
3871 };
3872 ATTRIBUTE_GROUPS(ibmvscsis_dev);
3873
3874 static struct class ibmvscsis_class = {
3875         .name           = "ibmvscsis",
3876         .dev_release    = ibmvscsis_dev_release,
3877         .class_attrs    = ibmvscsis_class_attrs,
3878         .dev_groups     = ibmvscsis_dev_groups,
3879 };
3880
3881 static struct vio_device_id ibmvscsis_device_table[] = {
3882         { "v-scsi-host", "IBM,v-scsi-host" },
3883         { "", "" }
3884 };
3885 MODULE_DEVICE_TABLE(vio, ibmvscsis_device_table);
3886
3887 static struct vio_driver ibmvscsis_driver = {
3888         .name = "ibmvscsis",
3889         .id_table = ibmvscsis_device_table,
3890         .probe = ibmvscsis_probe,
3891         .remove = ibmvscsis_remove,
3892 };
3893
3894 /*
3895  * ibmvscsis_init() - Kernel Module initialization
3896  *
3897  * Note: vio_register_driver() registers callback functions, and at least one
3898  * of those callback functions calls TCM - Linux IO Target Subsystem, thus
3899  * the SCSI Target template must be registered before vio_register_driver()
3900  * is called.
3901  */
3902 static int __init ibmvscsis_init(void)
3903 {
3904         int rc = 0;
3905
3906         rc = ibmvscsis_get_system_info();
3907         if (rc) {
3908                 pr_err("rc %d from get_system_info\n", rc);
3909                 goto out;
3910         }
3911
3912         rc = class_register(&ibmvscsis_class);
3913         if (rc) {
3914                 pr_err("failed class register\n");
3915                 goto out;
3916         }
3917
3918         rc = target_register_template(&ibmvscsis_ops);
3919         if (rc) {
3920                 pr_err("rc %d from target_register_template\n", rc);
3921                 goto unregister_class;
3922         }
3923
3924         rc = vio_register_driver(&ibmvscsis_driver);
3925         if (rc) {
3926                 pr_err("rc %d from vio_register_driver\n", rc);
3927                 goto unregister_target;
3928         }
3929
3930         return 0;
3931
3932 unregister_target:
3933         target_unregister_template(&ibmvscsis_ops);
3934 unregister_class:
3935         class_unregister(&ibmvscsis_class);
3936 out:
3937         return rc;
3938 }
3939
3940 static void __exit ibmvscsis_exit(void)
3941 {
3942         pr_info("Unregister IBM virtual SCSI host driver\n");
3943         vio_unregister_driver(&ibmvscsis_driver);
3944         target_unregister_template(&ibmvscsis_ops);
3945         class_unregister(&ibmvscsis_class);
3946 }
3947
3948 MODULE_DESCRIPTION("IBMVSCSIS fabric driver");
3949 MODULE_AUTHOR("Bryant G. Ly and Michael Cyr");
3950 MODULE_LICENSE("GPL");
3951 MODULE_VERSION(IBMVSCSIS_VERSION);
3952 module_init(ibmvscsis_init);
3953 module_exit(ibmvscsis_exit);