drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * IBM Virtual SCSI Target Driver
   4  * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
   5  *                         Santiago Leon (santil@us.ibm.com) IBM Corp.
   6  *                         Linda Xie (lxie@us.ibm.com) IBM Corp.
   7  *
   8  * Copyright (C) 2005-2011 FUJITA Tomonori <tomof@acm.org>
   9  * Copyright (C) 2010 Nicholas A. Bellinger <nab@kernel.org>
  10  *
  11  * Authors: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
  12  * Authors: Michael Cyr <mikecyr@linux.vnet.ibm.com>
  13  *
  14  ****************************************************************************/
  15
  16 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/slab.h>
  21 #include <linux/types.h>
  22 #include <linux/list.h>
  23 #include <linux/string.h>
  24 #include <linux/delay.h>
  25 #include <linux/of.h>
  26
  27 #include <target/target_core_base.h>
  28 #include <target/target_core_fabric.h>
  29
  30 #include <asm/hvcall.h>
  31 #include <asm/vio.h>
  32
  33 #include <scsi/viosrp.h>
  34
  35 #include "ibmvscsi_tgt.h"
  36
  37 #define IBMVSCSIS_VERSION       "v0.2"
  38
  39 #define INITIAL_SRP_LIMIT       1024
  40 #define DEFAULT_MAX_SECTORS     256
  41 #define MAX_TXU                 1024 * 1024
  42
  43 static uint max_vdma_size = MAX_H_COPY_RDMA;
  44
  45 static char system_id[SYS_ID_NAME_LEN] = "";
  46 static char partition_name[PARTITION_NAMELEN] = "UNKNOWN";
  47 static uint partition_number = -1;
  48
  49 /* Adapter list and lock to control it */
  50 static DEFINE_SPINLOCK(ibmvscsis_dev_lock);
  51 static LIST_HEAD(ibmvscsis_dev_list);
  52
  53 static long ibmvscsis_parse_command(struct scsi_info *vscsi,
  54                                     struct viosrp_crq *crq);
  55
  56 static void ibmvscsis_adapter_idle(struct scsi_info *vscsi);
  57
  58 static void ibmvscsis_determine_resid(struct se_cmd *se_cmd,
  59                                       struct srp_rsp *rsp)
  60 {
  61         u32 residual_count = se_cmd->residual_count;
  62
  63         if (!residual_count)
  64                 return;
  65
  66         if (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
  67                 if (se_cmd->data_direction == DMA_TO_DEVICE) {
  68                         /* residual data from an underflow write */
  69                         rsp->flags = SRP_RSP_FLAG_DOUNDER;
  70                         rsp->data_out_res_cnt = cpu_to_be32(residual_count);
  71                 } else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
  72                         /* residual data from an underflow read */
  73                         rsp->flags = SRP_RSP_FLAG_DIUNDER;
  74                         rsp->data_in_res_cnt = cpu_to_be32(residual_count);
  75                 }
  76         } else if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
  77                 if (se_cmd->data_direction == DMA_TO_DEVICE) {
  78                         /* residual data from an overflow write */
  79                         rsp->flags = SRP_RSP_FLAG_DOOVER;
  80                         rsp->data_out_res_cnt = cpu_to_be32(residual_count);
  81                 } else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
  82                         /* residual data from an overflow read */
  83                         rsp->flags = SRP_RSP_FLAG_DIOVER;
  84                         rsp->data_in_res_cnt = cpu_to_be32(residual_count);
  85                 }
  86         }
  87 }
  88
  89 /**
  90  * connection_broken() - Determine if the connection to the client is good
  91  * @vscsi:      Pointer to our adapter structure
  92  *
  93  * This function attempts to send a ping MAD to the client. If the call to
  94  * queue the request returns H_CLOSED then the connection has been broken
  95  * and the function returns TRUE.
  96  *
  97  * EXECUTION ENVIRONMENT:
  98  *      Interrupt or Process environment
  99  */
 100 static bool connection_broken(struct scsi_info *vscsi)
 101 {
 102         struct viosrp_crq *crq;
 103         u64 buffer[2] = { 0, 0 };
 104         long h_return_code;
 105         bool rc = false;
 106
 107         /* create a PING crq */
 108         crq = (struct viosrp_crq *)&buffer;
 109         crq->valid = VALID_CMD_RESP_EL;
 110         crq->format = MESSAGE_IN_CRQ;
 111         crq->status = PING;
 112
 113         h_return_code = h_send_crq(vscsi->dds.unit_id,
 114                                    cpu_to_be64(buffer[MSG_HI]),
 115                                    cpu_to_be64(buffer[MSG_LOW]));
 116
 117         dev_dbg(&vscsi->dev, "Connection_broken: rc %ld\n", h_return_code);
 118
 119         if (h_return_code == H_CLOSED)
 120                 rc = true;
 121
 122         return rc;
 123 }
 124
 125 /**
 126  * ibmvscsis_unregister_command_q() - Helper Function-Unregister Command Queue
 127  * @vscsi:      Pointer to our adapter structure
 128  *
 129  * This function calls h_free_q then frees the interrupt bit etc.
 130  * It must release the lock before doing so because of the time it can take
 131  * for h_free_crq in PHYP
 132  * NOTE: * the caller must make sure that state and or flags will prevent
 133  *         interrupt handler from scheduling work.
 134  *       * anyone calling this function may need to set the CRQ_CLOSED flag
 135  *         we can't do it here, because we don't have the lock
 136  *
 137  * EXECUTION ENVIRONMENT:
 138  *      Process level
 139  */
 140 static long ibmvscsis_unregister_command_q(struct scsi_info *vscsi)
 141 {
 142         long qrc;
 143         long rc = ADAPT_SUCCESS;
 144         int ticks = 0;
 145
 146         do {
 147                 qrc = h_free_crq(vscsi->dds.unit_id);
 148                 switch (qrc) {
 149                 case H_SUCCESS:
 150                         spin_lock_bh(&vscsi->intr_lock);
 151                         vscsi->flags &= ~PREP_FOR_SUSPEND_FLAGS;
 152                         spin_unlock_bh(&vscsi->intr_lock);
 153                         break;
 154
 155                 case H_HARDWARE:
 156                 case H_PARAMETER:
 157                         dev_err(&vscsi->dev, "unregister_command_q: error from h_free_crq %ld\n",
 158                                 qrc);
 159                         rc = ERROR;
 160                         break;
 161
 162                 case H_BUSY:
 163                 case H_LONG_BUSY_ORDER_1_MSEC:
 164                         /* msleep not good for small values */
 165                         usleep_range(1000, 2000);
 166                         ticks += 1;
 167                         break;
 168                 case H_LONG_BUSY_ORDER_10_MSEC:
 169                         usleep_range(10000, 20000);
 170                         ticks += 10;
 171                         break;
 172                 case H_LONG_BUSY_ORDER_100_MSEC:
 173                         msleep(100);
 174                         ticks += 100;
 175                         break;
 176                 case H_LONG_BUSY_ORDER_1_SEC:
 177                         ssleep(1);
 178                         ticks += 1000;
 179                         break;
 180                 case H_LONG_BUSY_ORDER_10_SEC:
 181                         ssleep(10);
 182                         ticks += 10000;
 183                         break;
 184                 case H_LONG_BUSY_ORDER_100_SEC:
 185                         ssleep(100);
 186                         ticks += 100000;
 187                         break;
 188                 default:
 189                         dev_err(&vscsi->dev, "unregister_command_q: unknown error %ld from h_free_crq\n",
 190                                 qrc);
 191                         rc = ERROR;
 192                         break;
 193                 }
 194
 195                 /*
 196                  * dont wait more then 300 seconds
 197                  * ticks are in milliseconds more or less
 198                  */
 199                 if (ticks > 300000 && qrc != H_SUCCESS) {
 200                         rc = ERROR;
 201                         dev_err(&vscsi->dev, "Excessive wait for h_free_crq\n");
 202                 }
 203         } while (qrc != H_SUCCESS && rc == ADAPT_SUCCESS);
 204
 205         dev_dbg(&vscsi->dev, "Freeing CRQ: phyp rc %ld, rc %ld\n", qrc, rc);
 206
 207         return rc;
 208 }
 209
 210 /**
 211  * ibmvscsis_delete_client_info() - Helper function to Delete Client Info
 212  * @vscsi:      Pointer to our adapter structure
 213  * @client_closed:      True if client closed its queue
 214  *
 215  * Deletes information specific to the client when the client goes away
 216  *
 217  * EXECUTION ENVIRONMENT:
 218  *      Interrupt or Process
 219  */
 220 static void ibmvscsis_delete_client_info(struct scsi_info *vscsi,
 221                                          bool client_closed)
 222 {
 223         vscsi->client_cap = 0;
 224
 225         /*
 226          * Some things we don't want to clear if we're closing the queue,
 227          * because some clients don't resend the host handshake when they
 228          * get a transport event.
 229          */
 230         if (client_closed)
 231                 vscsi->client_data.os_type = 0;
 232 }
 233
 234 /**
 235  * ibmvscsis_free_command_q() - Free Command Queue
 236  * @vscsi:      Pointer to our adapter structure
 237  *
 238  * This function calls unregister_command_q, then clears interrupts and
 239  * any pending interrupt acknowledgments associated with the command q.
 240  * It also clears memory if there is no error.
 241  *
 242  * PHYP did not meet the PAPR architecture so that we must give up the
 243  * lock. This causes a timing hole regarding state change.  To close the
 244  * hole this routine does accounting on any change that occurred during
 245  * the time the lock is not held.
 246  * NOTE: must give up and then acquire the interrupt lock, the caller must
 247  *       make sure that state and or flags will prevent interrupt handler from
 248  *       scheduling work.
 249  *
 250  * EXECUTION ENVIRONMENT:
 251  *      Process level, interrupt lock is held
 252  */
 253 static long ibmvscsis_free_command_q(struct scsi_info *vscsi)
 254 {
 255         int bytes;
 256         u32 flags_under_lock;
 257         u16 state_under_lock;
 258         long rc = ADAPT_SUCCESS;
 259
 260         if (!(vscsi->flags & CRQ_CLOSED)) {
 261                 vio_disable_interrupts(vscsi->dma_dev);
 262
 263                 state_under_lock = vscsi->new_state;
 264                 flags_under_lock = vscsi->flags;
 265                 vscsi->phyp_acr_state = 0;
 266                 vscsi->phyp_acr_flags = 0;
 267
 268                 spin_unlock_bh(&vscsi->intr_lock);
 269                 rc = ibmvscsis_unregister_command_q(vscsi);
 270                 spin_lock_bh(&vscsi->intr_lock);
 271
 272                 if (state_under_lock != vscsi->new_state)
 273                         vscsi->phyp_acr_state = vscsi->new_state;
 274
 275                 vscsi->phyp_acr_flags = ((~flags_under_lock) & vscsi->flags);
 276
 277                 if (rc == ADAPT_SUCCESS) {
 278                         bytes = vscsi->cmd_q.size * PAGE_SIZE;
 279                         memset(vscsi->cmd_q.base_addr, 0, bytes);
 280                         vscsi->cmd_q.index = 0;
 281                         vscsi->flags |= CRQ_CLOSED;
 282
 283                         ibmvscsis_delete_client_info(vscsi, false);
 284                 }
 285
 286                 dev_dbg(&vscsi->dev, "free_command_q: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
 287                         vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
 288                         vscsi->phyp_acr_state);
 289         }
 290         return rc;
 291 }
 292
 293 /**
 294  * ibmvscsis_cmd_q_dequeue() - Get valid Command element
 295  * @mask:       Mask to use in case index wraps
 296  * @current_index:      Current index into command queue
 297  * @base_addr:  Pointer to start of command queue
 298  *
 299  * Returns a pointer to a valid command element or NULL, if the command
 300  * queue is empty
 301  *
 302  * EXECUTION ENVIRONMENT:
 303  *      Interrupt environment, interrupt lock held
 304  */
 305 static struct viosrp_crq *ibmvscsis_cmd_q_dequeue(uint mask,
 306                                                   uint *current_index,
 307                                                   struct viosrp_crq *base_addr)
 308 {
 309         struct viosrp_crq *ptr;
 310
 311         ptr = base_addr + *current_index;
 312
 313         if (ptr->valid) {
 314                 *current_index = (*current_index + 1) & mask;
 315                 dma_rmb();
 316         } else {
 317                 ptr = NULL;
 318         }
 319
 320         return ptr;
 321 }
 322
 323 /**
 324  * ibmvscsis_send_init_message() - send initialize message to the client
 325  * @vscsi:      Pointer to our adapter structure
 326  * @format:     Which Init Message format to send
 327  *
 328  * EXECUTION ENVIRONMENT:
 329  *      Interrupt environment interrupt lock held
 330  */
 331 static long ibmvscsis_send_init_message(struct scsi_info *vscsi, u8 format)
 332 {
 333         struct viosrp_crq *crq;
 334         u64 buffer[2] = { 0, 0 };
 335         long rc;
 336
 337         crq = (struct viosrp_crq *)&buffer;
 338         crq->valid = VALID_INIT_MSG;
 339         crq->format = format;
 340         rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
 341                         cpu_to_be64(buffer[MSG_LOW]));
 342
 343         return rc;
 344 }
 345
 346 /**
 347  * ibmvscsis_check_init_msg() - Check init message valid
 348  * @vscsi:      Pointer to our adapter structure
 349  * @format:     Pointer to return format of Init Message, if any.
 350  *              Set to UNUSED_FORMAT if no Init Message in queue.
 351  *
 352  * Checks if an initialize message was queued by the initiatior
 353  * after the queue was created and before the interrupt was enabled.
 354  *
 355  * EXECUTION ENVIRONMENT:
 356  *      Process level only, interrupt lock held
 357  */
 358 static long ibmvscsis_check_init_msg(struct scsi_info *vscsi, uint *format)
 359 {
 360         struct viosrp_crq *crq;
 361         long rc = ADAPT_SUCCESS;
 362
 363         crq = ibmvscsis_cmd_q_dequeue(vscsi->cmd_q.mask, &vscsi->cmd_q.index,
 364                                       vscsi->cmd_q.base_addr);
 365         if (!crq) {
 366                 *format = (uint)UNUSED_FORMAT;
 367         } else if (crq->valid == VALID_INIT_MSG && crq->format == INIT_MSG) {
 368                 *format = (uint)INIT_MSG;
 369                 crq->valid = INVALIDATE_CMD_RESP_EL;
 370                 dma_rmb();
 371
 372                 /*
 373                  * the caller has ensured no initialize message was
 374                  * sent after the queue was
 375                  * created so there should be no other message on the queue.
 376                  */
 377                 crq = ibmvscsis_cmd_q_dequeue(vscsi->cmd_q.mask,
 378                                               &vscsi->cmd_q.index,
 379                                               vscsi->cmd_q.base_addr);
 380                 if (crq) {
 381                         *format = (uint)(crq->format);
 382                         rc = ERROR;
 383                         crq->valid = INVALIDATE_CMD_RESP_EL;
 384                         dma_rmb();
 385                 }
 386         } else {
 387                 *format = (uint)(crq->format);
 388                 rc = ERROR;
 389                 crq->valid = INVALIDATE_CMD_RESP_EL;
 390                 dma_rmb();
 391         }
 392
 393         return rc;
 394 }
 395
 396 /**
 397  * ibmvscsis_disconnect() - Helper function to disconnect
 398  * @work:       Pointer to work_struct, gives access to our adapter structure
 399  *
 400  * An error has occurred or the driver received a Transport event,
 401  * and the driver is requesting that the command queue be de-registered
 402  * in a safe manner. If there is no outstanding I/O then we can stop the
 403  * queue. If we are restarting the queue it will be reflected in the
 404  * the state of the adapter.
 405  *
 406  * EXECUTION ENVIRONMENT:
 407  *      Process environment
 408  */
 409 static void ibmvscsis_disconnect(struct work_struct *work)
 410 {
 411         struct scsi_info *vscsi = container_of(work, struct scsi_info,
 412                                                proc_work);
 413         u16 new_state;
 414         bool wait_idle = false;
 415
 416         spin_lock_bh(&vscsi->intr_lock);
 417         new_state = vscsi->new_state;
 418         vscsi->new_state = 0;
 419
 420         vscsi->flags |= DISCONNECT_SCHEDULED;
 421         vscsi->flags &= ~SCHEDULE_DISCONNECT;
 422
 423         dev_dbg(&vscsi->dev, "disconnect: flags 0x%x, state 0x%hx\n",
 424                 vscsi->flags, vscsi->state);
 425
 426         /*
 427          * check which state we are in and see if we
 428          * should transitition to the new state
 429          */
 430         switch (vscsi->state) {
 431         /* Should never be called while in this state. */
 432         case NO_QUEUE:
 433         /*
 434          * Can never transition from this state;
 435          * igonore errors and logout.
 436          */
 437         case UNCONFIGURING:
 438                 break;
 439
 440         /* can transition from this state to UNCONFIGURING */
 441         case ERR_DISCONNECT:
 442                 if (new_state == UNCONFIGURING)
 443                         vscsi->state = new_state;
 444                 break;
 445
 446         /*
 447          * Can transition from this state to to unconfiguring
 448          * or err disconnect.
 449          */
 450         case ERR_DISCONNECT_RECONNECT:
 451                 switch (new_state) {
 452                 case UNCONFIGURING:
 453                 case ERR_DISCONNECT:
 454                         vscsi->state = new_state;
 455                         break;
 456
 457                 case WAIT_IDLE:
 458                         break;
 459                 default:
 460                         break;
 461                 }
 462                 break;
 463
 464         /* can transition from this state to UNCONFIGURING */
 465         case ERR_DISCONNECTED:
 466                 if (new_state == UNCONFIGURING)
 467                         vscsi->state = new_state;
 468                 break;
 469
 470         case WAIT_ENABLED:
 471                 switch (new_state) {
 472                 case UNCONFIGURING:
 473                         vscsi->state = new_state;
 474                         vscsi->flags |= RESPONSE_Q_DOWN;
 475                         vscsi->flags &= ~(SCHEDULE_DISCONNECT |
 476                                           DISCONNECT_SCHEDULED);
 477                         dma_rmb();
 478                         if (vscsi->flags & CFG_SLEEPING) {
 479                                 vscsi->flags &= ~CFG_SLEEPING;
 480                                 complete(&vscsi->unconfig);
 481                         }
 482                         break;
 483
 484                 /* should never happen */
 485                 case ERR_DISCONNECT:
 486                 case ERR_DISCONNECT_RECONNECT:
 487                 case WAIT_IDLE:
 488                         dev_err(&vscsi->dev, "disconnect: invalid state %d for WAIT_IDLE\n",
 489                                 vscsi->state);
 490                         break;
 491                 }
 492                 break;
 493
 494         case WAIT_IDLE:
 495                 switch (new_state) {
 496                 case UNCONFIGURING:
 497                         vscsi->flags |= RESPONSE_Q_DOWN;
 498                         vscsi->state = new_state;
 499                         vscsi->flags &= ~(SCHEDULE_DISCONNECT |
 500                                           DISCONNECT_SCHEDULED);
 501                         ibmvscsis_free_command_q(vscsi);
 502                         break;
 503                 case ERR_DISCONNECT:
 504                 case ERR_DISCONNECT_RECONNECT:
 505                         vscsi->state = new_state;
 506                         break;
 507                 }
 508                 break;
 509
 510         /*
 511          * Initiator has not done a successful srp login
 512          * or has done a successful srp logout ( adapter was not
 513          * busy). In the first case there can be responses queued
 514          * waiting for space on the initiators response queue (MAD)
 515          * The second case the adapter is idle. Assume the worse case,
 516          * i.e. the second case.
 517          */
 518         case WAIT_CONNECTION:
 519         case CONNECTED:
 520         case SRP_PROCESSING:
 521                 wait_idle = true;
 522                 vscsi->state = new_state;
 523                 break;
 524
 525         /* can transition from this state to UNCONFIGURING */
 526         case UNDEFINED:
 527                 if (new_state == UNCONFIGURING)
 528                         vscsi->state = new_state;
 529                 break;
 530         default:
 531                 break;
 532         }
 533
 534         if (wait_idle) {
 535                 dev_dbg(&vscsi->dev, "disconnect start wait, active %d, sched %d\n",
 536                         (int)list_empty(&vscsi->active_q),
 537                         (int)list_empty(&vscsi->schedule_q));
 538                 if (!list_empty(&vscsi->active_q) ||
 539                     !list_empty(&vscsi->schedule_q)) {
 540                         vscsi->flags |= WAIT_FOR_IDLE;
 541                         dev_dbg(&vscsi->dev, "disconnect flags 0x%x\n",
 542                                 vscsi->flags);
 543                         /*
 544                          * This routine is can not be called with the interrupt
 545                          * lock held.
 546                          */
 547                         spin_unlock_bh(&vscsi->intr_lock);
 548                         wait_for_completion(&vscsi->wait_idle);
 549                         spin_lock_bh(&vscsi->intr_lock);
 550                 }
 551                 dev_dbg(&vscsi->dev, "disconnect stop wait\n");
 552
 553                 ibmvscsis_adapter_idle(vscsi);
 554         }
 555
 556         spin_unlock_bh(&vscsi->intr_lock);
 557 }
 558
 559 /**
 560  * ibmvscsis_post_disconnect() - Schedule the disconnect
 561  * @vscsi:      Pointer to our adapter structure
 562  * @new_state:  State to move to after disconnecting
 563  * @flag_bits:  Flags to turn on in adapter structure
 564  *
 565  * If it's already been scheduled, then see if we need to "upgrade"
 566  * the new state (if the one passed in is more "severe" than the
 567  * previous one).
 568  *
 569  * PRECONDITION:
 570  *      interrupt lock is held
 571  */
 572 static void ibmvscsis_post_disconnect(struct scsi_info *vscsi, uint new_state,
 573                                       uint flag_bits)
 574 {
 575         uint state;
 576
 577         /* check the validity of the new state */
 578         switch (new_state) {
 579         case UNCONFIGURING:
 580         case ERR_DISCONNECT:
 581         case ERR_DISCONNECT_RECONNECT:
 582         case WAIT_IDLE:
 583                 break;
 584
 585         default:
 586                 dev_err(&vscsi->dev, "post_disconnect: Invalid new state %d\n",
 587                         new_state);
 588                 return;
 589         }
 590
 591         vscsi->flags |= flag_bits;
 592
 593         dev_dbg(&vscsi->dev, "post_disconnect: new_state 0x%x, flag_bits 0x%x, vscsi->flags 0x%x, state %hx\n",
 594                 new_state, flag_bits, vscsi->flags, vscsi->state);
 595
 596         if (!(vscsi->flags & (DISCONNECT_SCHEDULED | SCHEDULE_DISCONNECT))) {
 597                 vscsi->flags |= SCHEDULE_DISCONNECT;
 598                 vscsi->new_state = new_state;
 599
 600                 INIT_WORK(&vscsi->proc_work, ibmvscsis_disconnect);
 601                 (void)queue_work(vscsi->work_q, &vscsi->proc_work);
 602         } else {
 603                 if (vscsi->new_state)
 604                         state = vscsi->new_state;
 605                 else
 606                         state = vscsi->state;
 607
 608                 switch (state) {
 609                 case NO_QUEUE:
 610                 case UNCONFIGURING:
 611                         break;
 612
 613                 case ERR_DISCONNECTED:
 614                 case ERR_DISCONNECT:
 615                 case UNDEFINED:
 616                         if (new_state == UNCONFIGURING)
 617                                 vscsi->new_state = new_state;
 618                         break;
 619
 620                 case ERR_DISCONNECT_RECONNECT:
 621                         switch (new_state) {
 622                         case UNCONFIGURING:
 623                         case ERR_DISCONNECT:
 624                                 vscsi->new_state = new_state;
 625                                 break;
 626                         default:
 627                                 break;
 628                         }
 629                         break;
 630
 631                 case WAIT_ENABLED:
 632                 case WAIT_IDLE:
 633                 case WAIT_CONNECTION:
 634                 case CONNECTED:
 635                 case SRP_PROCESSING:
 636                         vscsi->new_state = new_state;
 637                         break;
 638
 639                 default:
 640                         break;
 641                 }
 642         }
 643
 644         dev_dbg(&vscsi->dev, "Leaving post_disconnect: flags 0x%x, new_state 0x%x\n",
 645                 vscsi->flags, vscsi->new_state);
 646 }
 647
 648 /**
 649  * ibmvscsis_handle_init_compl_msg() - Respond to an Init Complete Message
 650  * @vscsi:      Pointer to our adapter structure
 651  *
 652  * Must be called with interrupt lock held.
 653  */
 654 static long ibmvscsis_handle_init_compl_msg(struct scsi_info *vscsi)
 655 {
 656         long rc = ADAPT_SUCCESS;
 657
 658         switch (vscsi->state) {
 659         case NO_QUEUE:
 660         case ERR_DISCONNECT:
 661         case ERR_DISCONNECT_RECONNECT:
 662         case ERR_DISCONNECTED:
 663         case UNCONFIGURING:
 664         case UNDEFINED:
 665                 rc = ERROR;
 666                 break;
 667
 668         case WAIT_CONNECTION:
 669                 vscsi->state = CONNECTED;
 670                 break;
 671
 672         case WAIT_IDLE:
 673         case SRP_PROCESSING:
 674         case CONNECTED:
 675         case WAIT_ENABLED:
 676         default:
 677                 rc = ERROR;
 678                 dev_err(&vscsi->dev, "init_msg: invalid state %d to get init compl msg\n",
 679                         vscsi->state);
 680                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
 681                 break;
 682         }
 683
 684         return rc;
 685 }
 686
 687 /**
 688  * ibmvscsis_handle_init_msg() - Respond to an Init Message
 689  * @vscsi:      Pointer to our adapter structure
 690  *
 691  * Must be called with interrupt lock held.
 692  */
 693 static long ibmvscsis_handle_init_msg(struct scsi_info *vscsi)
 694 {
 695         long rc = ADAPT_SUCCESS;
 696
 697         switch (vscsi->state) {
 698         case WAIT_CONNECTION:
 699                 rc = ibmvscsis_send_init_message(vscsi, INIT_COMPLETE_MSG);
 700                 switch (rc) {
 701                 case H_SUCCESS:
 702                         vscsi->state = CONNECTED;
 703                         break;
 704
 705                 case H_PARAMETER:
 706                         dev_err(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
 707                                 rc);
 708                         ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
 709                         break;
 710
 711                 case H_DROPPED:
 712                         dev_err(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
 713                                 rc);
 714                         rc = ERROR;
 715                         ibmvscsis_post_disconnect(vscsi,
 716                                                   ERR_DISCONNECT_RECONNECT, 0);
 717                         break;
 718
 719                 case H_CLOSED:
 720                         dev_warn(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
 721                                  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         dev_dbg(&vscsi->dev, "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                 dev_dbg(&vscsi->dev, "init_msg, part num %d\n",
 774                         vscsi->client_data.partition_number);
 775         } else {
 776                 dev_dbg(&vscsi->dev, "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         rc = h_vioctl(vscsi->dds.unit_id, H_ENABLE_PREPARE_FOR_SUSPEND, 30000,
 806                       0, 0, 0, 0);
 807         if (rc == H_SUCCESS)
 808                 vscsi->flags |= PREP_FOR_SUSPEND_ENABLED;
 809         else if (rc != H_NOT_FOUND)
 810                 dev_err(&vscsi->dev, "Error from Enable Prepare for Suspend: %ld\n",
 811                         rc);
 812
 813         vscsi->flags &= PRESERVE_FLAG_FIELDS;
 814         vscsi->rsp_q_timer.timer_pops = 0;
 815         vscsi->debit = 0;
 816         vscsi->credit = 0;
 817
 818         rc = vio_enable_interrupts(vscsi->dma_dev);
 819         if (rc) {
 820                 dev_warn(&vscsi->dev, "establish_new_q: failed to enable interrupts, rc %ld\n",
 821                          rc);
 822                 return rc;
 823         }
 824
 825         rc = ibmvscsis_check_init_msg(vscsi, &format);
 826         if (rc) {
 827                 dev_err(&vscsi->dev, "establish_new_q: check_init_msg failed, rc %ld\n",
 828                         rc);
 829                 return rc;
 830         }
 831
 832         if (format == UNUSED_FORMAT) {
 833                 rc = ibmvscsis_send_init_message(vscsi, INIT_MSG);
 834                 switch (rc) {
 835                 case H_SUCCESS:
 836                 case H_DROPPED:
 837                 case H_CLOSED:
 838                         rc = ADAPT_SUCCESS;
 839                         break;
 840
 841                 case H_PARAMETER:
 842                 case H_HARDWARE:
 843                         break;
 844
 845                 default:
 846                         vscsi->state = UNDEFINED;
 847                         rc = H_HARDWARE;
 848                         break;
 849                 }
 850         } else if (format == INIT_MSG) {
 851                 rc = ibmvscsis_handle_init_msg(vscsi);
 852         }
 853
 854         return rc;
 855 }
 856
 857 /**
 858  * ibmvscsis_reset_queue() - Reset CRQ Queue
 859  * @vscsi:      Pointer to our adapter structure
 860  *
 861  * This function calls h_free_q and then calls h_reg_q and does all
 862  * of the bookkeeping to get us back to where we can communicate.
 863  *
 864  * Actually, we don't always call h_free_crq.  A problem was discovered
 865  * where one partition would close and reopen his queue, which would
 866  * cause his partner to get a transport event, which would cause him to
 867  * close and reopen his queue, which would cause the original partition
 868  * to get a transport event, etc., etc.  To prevent this, we don't
 869  * actually close our queue if the client initiated the reset, (i.e.
 870  * either we got a transport event or we have detected that the client's
 871  * queue is gone)
 872  *
 873  * EXECUTION ENVIRONMENT:
 874  *      Process environment, called with interrupt lock held
 875  */
 876 static void ibmvscsis_reset_queue(struct scsi_info *vscsi)
 877 {
 878         int bytes;
 879         long rc = ADAPT_SUCCESS;
 880
 881         dev_dbg(&vscsi->dev, "reset_queue: flags 0x%x\n", vscsi->flags);
 882
 883         /* don't reset, the client did it for us */
 884         if (vscsi->flags & (CLIENT_FAILED | TRANS_EVENT)) {
 885                 vscsi->flags &= PRESERVE_FLAG_FIELDS;
 886                 vscsi->rsp_q_timer.timer_pops = 0;
 887                 vscsi->debit = 0;
 888                 vscsi->credit = 0;
 889                 vscsi->state = WAIT_CONNECTION;
 890                 vio_enable_interrupts(vscsi->dma_dev);
 891         } else {
 892                 rc = ibmvscsis_free_command_q(vscsi);
 893                 if (rc == ADAPT_SUCCESS) {
 894                         vscsi->state = WAIT_CONNECTION;
 895
 896                         bytes = vscsi->cmd_q.size * PAGE_SIZE;
 897                         rc = h_reg_crq(vscsi->dds.unit_id,
 898                                        vscsi->cmd_q.crq_token, bytes);
 899                         if (rc == H_CLOSED || rc == H_SUCCESS) {
 900                                 rc = ibmvscsis_establish_new_q(vscsi);
 901                         }
 902
 903                         if (rc != ADAPT_SUCCESS) {
 904                                 dev_dbg(&vscsi->dev, "reset_queue: reg_crq rc %ld\n",
 905                                         rc);
 906
 907                                 vscsi->state = ERR_DISCONNECTED;
 908                                 vscsi->flags |= RESPONSE_Q_DOWN;
 909                                 ibmvscsis_free_command_q(vscsi);
 910                         }
 911                 } else {
 912                         vscsi->state = ERR_DISCONNECTED;
 913                         vscsi->flags |= RESPONSE_Q_DOWN;
 914                 }
 915         }
 916 }
 917
 918 /**
 919  * ibmvscsis_free_cmd_resources() - Free command resources
 920  * @vscsi:      Pointer to our adapter structure
 921  * @cmd:        Command which is not longer in use
 922  *
 923  * Must be called with interrupt lock held.
 924  */
 925 static void ibmvscsis_free_cmd_resources(struct scsi_info *vscsi,
 926                                          struct ibmvscsis_cmd *cmd)
 927 {
 928         struct iu_entry *iue = cmd->iue;
 929
 930         switch (cmd->type) {
 931         case TASK_MANAGEMENT:
 932         case SCSI_CDB:
 933                 /*
 934                  * When the queue goes down this value is cleared, so it
 935                  * cannot be cleared in this general purpose function.
 936                  */
 937                 if (vscsi->debit)
 938                         vscsi->debit -= 1;
 939                 break;
 940         case ADAPTER_MAD:
 941                 vscsi->flags &= ~PROCESSING_MAD;
 942                 break;
 943         case UNSET_TYPE:
 944                 break;
 945         default:
 946                 dev_err(&vscsi->dev, "free_cmd_resources unknown type %d\n",
 947                         cmd->type);
 948                 break;
 949         }
 950
 951         cmd->iue = NULL;
 952         list_add_tail(&cmd->list, &vscsi->free_cmd);
 953         srp_iu_put(iue);
 954
 955         if (list_empty(&vscsi->active_q) && list_empty(&vscsi->schedule_q) &&
 956             list_empty(&vscsi->waiting_rsp) && (vscsi->flags & WAIT_FOR_IDLE)) {
 957                 vscsi->flags &= ~WAIT_FOR_IDLE;
 958                 complete(&vscsi->wait_idle);
 959         }
 960 }
 961
 962 /**
 963  * ibmvscsis_ready_for_suspend() - Helper function to call VIOCTL
 964  * @vscsi:      Pointer to our adapter structure
 965  * @idle:       Indicates whether we were called from adapter_idle.  This
 966  *              is important to know if we need to do a disconnect, since if
 967  *              we're called from adapter_idle, we're still processing the
 968  *              current disconnect, so we can't just call post_disconnect.
 969  *
 970  * This function is called when the adapter is idle when phyp has sent
 971  * us a Prepare for Suspend Transport Event.
 972  *
 973  * EXECUTION ENVIRONMENT:
 974  *      Process or interrupt environment called with interrupt lock held
 975  */
 976 static long ibmvscsis_ready_for_suspend(struct scsi_info *vscsi, bool idle)
 977 {
 978         long rc = 0;
 979         struct viosrp_crq *crq;
 980
 981         /* See if there is a Resume event in the queue */
 982         crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
 983
 984         dev_dbg(&vscsi->dev, "ready_suspend: flags 0x%x, state 0x%hx crq_valid:%x\n",
 985                 vscsi->flags, vscsi->state, (int)crq->valid);
 986
 987         if (!(vscsi->flags & PREP_FOR_SUSPEND_ABORTED) && !(crq->valid)) {
 988                 rc = h_vioctl(vscsi->dds.unit_id, H_READY_FOR_SUSPEND, 0, 0, 0,
 989                               0, 0);
 990                 if (rc) {
 991                         dev_err(&vscsi->dev, "Ready for Suspend Vioctl failed: %ld\n",
 992                                 rc);
 993                         rc = 0;
 994                 }
 995         } else if (((vscsi->flags & PREP_FOR_SUSPEND_OVERWRITE) &&
 996                     (vscsi->flags & PREP_FOR_SUSPEND_ABORTED)) ||
 997                    ((crq->valid) && ((crq->valid != VALID_TRANS_EVENT) ||
 998                                      (crq->format != RESUME_FROM_SUSP)))) {
 999                 if (idle) {
1000                         vscsi->state = ERR_DISCONNECT_RECONNECT;
1001                         ibmvscsis_reset_queue(vscsi);
1002                         rc = -1;
1003                 } else if (vscsi->state == CONNECTED) {
1004                         ibmvscsis_post_disconnect(vscsi,
1005                                                   ERR_DISCONNECT_RECONNECT, 0);
1006                 }
1007
1008                 vscsi->flags &= ~PREP_FOR_SUSPEND_OVERWRITE;
1009
1010                 if ((crq->valid) && ((crq->valid != VALID_TRANS_EVENT) ||
1011                                      (crq->format != RESUME_FROM_SUSP)))
1012                         dev_err(&vscsi->dev, "Invalid element in CRQ after Prepare for Suspend");
1013         }
1014
1015         vscsi->flags &= ~(PREP_FOR_SUSPEND_PENDING | PREP_FOR_SUSPEND_ABORTED);
1016
1017         return rc;
1018 }
1019
1020 /**
1021  * ibmvscsis_trans_event() - Handle a Transport Event
1022  * @vscsi:      Pointer to our adapter structure
1023  * @crq:        Pointer to CRQ entry containing the Transport Event
1024  *
1025  * Do the logic to close the I_T nexus.  This function may not
1026  * behave to specification.
1027  *
1028  * EXECUTION ENVIRONMENT:
1029  *      Interrupt, interrupt lock held
1030  */
1031 static long ibmvscsis_trans_event(struct scsi_info *vscsi,
1032                                   struct viosrp_crq *crq)
1033 {
1034         long rc = ADAPT_SUCCESS;
1035
1036         dev_dbg(&vscsi->dev, "trans_event: format %d, flags 0x%x, state 0x%hx\n",
1037                 (int)crq->format, vscsi->flags, vscsi->state);
1038
1039         switch (crq->format) {
1040         case MIGRATED:
1041         case PARTNER_FAILED:
1042         case PARTNER_DEREGISTER:
1043                 ibmvscsis_delete_client_info(vscsi, true);
1044                 if (crq->format == MIGRATED)
1045                         vscsi->flags &= ~PREP_FOR_SUSPEND_OVERWRITE;
1046                 switch (vscsi->state) {
1047                 case NO_QUEUE:
1048                 case ERR_DISCONNECTED:
1049                 case UNDEFINED:
1050                         break;
1051
1052                 case UNCONFIGURING:
1053                         vscsi->flags |= (RESPONSE_Q_DOWN | TRANS_EVENT);
1054                         break;
1055
1056                 case WAIT_ENABLED:
1057                         break;
1058
1059                 case WAIT_CONNECTION:
1060                         break;
1061
1062                 case CONNECTED:
1063                         ibmvscsis_post_disconnect(vscsi, WAIT_IDLE,
1064                                                   (RESPONSE_Q_DOWN |
1065                                                    TRANS_EVENT));
1066                         break;
1067
1068                 case SRP_PROCESSING:
1069                         if ((vscsi->debit > 0) ||
1070                             !list_empty(&vscsi->schedule_q) ||
1071                             !list_empty(&vscsi->waiting_rsp) ||
1072                             !list_empty(&vscsi->active_q)) {
1073                                 dev_dbg(&vscsi->dev, "debit %d, sched %d, wait %d, active %d\n",
1074                                         vscsi->debit,
1075                                         (int)list_empty(&vscsi->schedule_q),
1076                                         (int)list_empty(&vscsi->waiting_rsp),
1077                                         (int)list_empty(&vscsi->active_q));
1078                                 dev_warn(&vscsi->dev, "connection lost with outstanding work\n");
1079                         } else {
1080                                 dev_dbg(&vscsi->dev, "trans_event: SRP Processing, but no outstanding work\n");
1081                         }
1082
1083                         ibmvscsis_post_disconnect(vscsi, WAIT_IDLE,
1084                                                   (RESPONSE_Q_DOWN |
1085                                                    TRANS_EVENT));
1086                         break;
1087
1088                 case ERR_DISCONNECT:
1089                 case ERR_DISCONNECT_RECONNECT:
1090                 case WAIT_IDLE:
1091                         vscsi->flags |= (RESPONSE_Q_DOWN | TRANS_EVENT);
1092                         break;
1093                 }
1094                 break;
1095
1096         case PREPARE_FOR_SUSPEND:
1097                 dev_dbg(&vscsi->dev, "Prep for Suspend, crq status = 0x%x\n",
1098                         (int)crq->status);
1099                 switch (vscsi->state) {
1100                 case ERR_DISCONNECTED:
1101                 case WAIT_CONNECTION:
1102                 case CONNECTED:
1103                         ibmvscsis_ready_for_suspend(vscsi, false);
1104                         break;
1105                 case SRP_PROCESSING:
1106                         vscsi->resume_state = vscsi->state;
1107                         vscsi->flags |= PREP_FOR_SUSPEND_PENDING;
1108                         if (crq->status == CRQ_ENTRY_OVERWRITTEN)
1109                                 vscsi->flags |= PREP_FOR_SUSPEND_OVERWRITE;
1110                         ibmvscsis_post_disconnect(vscsi, WAIT_IDLE, 0);
1111                         break;
1112                 case NO_QUEUE:
1113                 case UNDEFINED:
1114                 case UNCONFIGURING:
1115                 case WAIT_ENABLED:
1116                 case ERR_DISCONNECT:
1117                 case ERR_DISCONNECT_RECONNECT:
1118                 case WAIT_IDLE:
1119                         dev_err(&vscsi->dev, "Invalid state for Prepare for Suspend Trans Event: 0x%x\n",
1120                                 vscsi->state);
1121                         break;
1122                 }
1123                 break;
1124
1125         case RESUME_FROM_SUSP:
1126                 dev_dbg(&vscsi->dev, "Resume from Suspend, crq status = 0x%x\n",
1127                         (int)crq->status);
1128                 if (vscsi->flags & PREP_FOR_SUSPEND_PENDING) {
1129                         vscsi->flags |= PREP_FOR_SUSPEND_ABORTED;
1130                 } else {
1131                         if ((crq->status == CRQ_ENTRY_OVERWRITTEN) ||
1132                             (vscsi->flags & PREP_FOR_SUSPEND_OVERWRITE)) {
1133                                 ibmvscsis_post_disconnect(vscsi,
1134                                                           ERR_DISCONNECT_RECONNECT,
1135                                                           0);
1136                                 vscsi->flags &= ~PREP_FOR_SUSPEND_OVERWRITE;
1137                         }
1138                 }
1139                 break;
1140
1141         default:
1142                 rc = ERROR;
1143                 dev_err(&vscsi->dev, "trans_event: invalid format %d\n",
1144                         (uint)crq->format);
1145                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT,
1146                                           RESPONSE_Q_DOWN);
1147                 break;
1148         }
1149
1150         rc = vscsi->flags & SCHEDULE_DISCONNECT;
1151
1152         dev_dbg(&vscsi->dev, "Leaving trans_event: flags 0x%x, state 0x%hx, rc %ld\n",
1153                 vscsi->flags, vscsi->state, rc);
1154
1155         return rc;
1156 }
1157
1158 /**
1159  * ibmvscsis_poll_cmd_q() - Poll Command Queue
1160  * @vscsi:      Pointer to our adapter structure
1161  *
1162  * Called to handle command elements that may have arrived while
1163  * interrupts were disabled.
1164  *
1165  * EXECUTION ENVIRONMENT:
1166  *      intr_lock must be held
1167  */
1168 static void ibmvscsis_poll_cmd_q(struct scsi_info *vscsi)
1169 {
1170         struct viosrp_crq *crq;
1171         long rc;
1172         bool ack = true;
1173         volatile u8 valid;
1174
1175         dev_dbg(&vscsi->dev, "poll_cmd_q: flags 0x%x, state 0x%hx, q index %ud\n",
1176                 vscsi->flags, vscsi->state, vscsi->cmd_q.index);
1177
1178         rc = vscsi->flags & SCHEDULE_DISCONNECT;
1179         crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
1180         valid = crq->valid;
1181         dma_rmb();
1182
1183         while (valid) {
1184 poll_work:
1185                 vscsi->cmd_q.index =
1186                         (vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
1187
1188                 if (!rc) {
1189                         rc = ibmvscsis_parse_command(vscsi, crq);
1190                 } else {
1191                         if ((uint)crq->valid == VALID_TRANS_EVENT) {
1192                                 /*
1193                                  * must service the transport layer events even
1194                                  * in an error state, dont break out until all
1195                                  * the consecutive transport events have been
1196                                  * processed
1197                                  */
1198                                 rc = ibmvscsis_trans_event(vscsi, crq);
1199                         } else if (vscsi->flags & TRANS_EVENT) {
1200                                 /*
1201                                  * if a tranport event has occurred leave
1202                                  * everything but transport events on the queue
1203                                  */
1204                                 dev_dbg(&vscsi->dev, "poll_cmd_q, ignoring\n");
1205
1206                                 /*
1207                                  * need to decrement the queue index so we can
1208                                  * look at the elment again
1209                                  */
1210                                 if (vscsi->cmd_q.index)
1211                                         vscsi->cmd_q.index -= 1;
1212                                 else
1213                                         /*
1214                                          * index is at 0 it just wrapped.
1215                                          * have it index last element in q
1216                                          */
1217                                         vscsi->cmd_q.index = vscsi->cmd_q.mask;
1218                                 break;
1219                         }
1220                 }
1221
1222                 crq->valid = INVALIDATE_CMD_RESP_EL;
1223
1224                 crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
1225                 valid = crq->valid;
1226                 dma_rmb();
1227         }
1228
1229         if (!rc) {
1230                 if (ack) {
1231                         vio_enable_interrupts(vscsi->dma_dev);
1232                         ack = false;
1233                         dev_dbg(&vscsi->dev, "poll_cmd_q, reenabling interrupts\n");
1234                 }
1235                 valid = crq->valid;
1236                 dma_rmb();
1237                 if (valid)
1238                         goto poll_work;
1239         }
1240
1241         dev_dbg(&vscsi->dev, "Leaving poll_cmd_q: rc %ld\n", rc);
1242 }
1243
1244 /**
1245  * ibmvscsis_free_cmd_qs() - Free elements in queue
1246  * @vscsi:      Pointer to our adapter structure
1247  *
1248  * Free all of the elements on all queues that are waiting for
1249  * whatever reason.
1250  *
1251  * PRECONDITION:
1252  *      Called with interrupt lock held
1253  */
1254 static void ibmvscsis_free_cmd_qs(struct scsi_info *vscsi)
1255 {
1256         struct ibmvscsis_cmd *cmd, *nxt;
1257
1258         dev_dbg(&vscsi->dev, "free_cmd_qs: waiting_rsp empty %d, timer starter %d\n",
1259                 (int)list_empty(&vscsi->waiting_rsp),
1260                 vscsi->rsp_q_timer.started);
1261
1262         list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp, list) {
1263                 list_del(&cmd->list);
1264                 ibmvscsis_free_cmd_resources(vscsi, cmd);
1265         }
1266 }
1267
1268 /**
1269  * ibmvscsis_get_free_cmd() - Get free command from list
1270  * @vscsi:      Pointer to our adapter structure
1271  *
1272  * Must be called with interrupt lock held.
1273  */
1274 static struct ibmvscsis_cmd *ibmvscsis_get_free_cmd(struct scsi_info *vscsi)
1275 {
1276         struct ibmvscsis_cmd *cmd = NULL;
1277         struct iu_entry *iue;
1278
1279         iue = srp_iu_get(&vscsi->target);
1280         if (iue) {
1281                 cmd = list_first_entry_or_null(&vscsi->free_cmd,
1282                                                struct ibmvscsis_cmd, list);
1283                 if (cmd) {
1284                         if (cmd->abort_cmd)
1285                                 cmd->abort_cmd = NULL;
1286                         cmd->flags &= ~(DELAY_SEND);
1287                         list_del(&cmd->list);
1288                         cmd->iue = iue;
1289                         cmd->type = UNSET_TYPE;
1290                         memset(&cmd->se_cmd, 0, sizeof(cmd->se_cmd));
1291                 } else {
1292                         srp_iu_put(iue);
1293                 }
1294         }
1295
1296         return cmd;
1297 }
1298
1299 /**
1300  * ibmvscsis_adapter_idle() - Helper function to handle idle adapter
1301  * @vscsi:      Pointer to our adapter structure
1302  *
1303  * This function is called when the adapter is idle when the driver
1304  * is attempting to clear an error condition.
1305  * The adapter is considered busy if any of its cmd queues
1306  * are non-empty. This function can be invoked
1307  * from the off level disconnect function.
1308  *
1309  * EXECUTION ENVIRONMENT:
1310  *      Process environment called with interrupt lock held
1311  */
1312 static void ibmvscsis_adapter_idle(struct scsi_info *vscsi)
1313 {
1314         int free_qs = false;
1315         long rc = 0;
1316
1317         dev_dbg(&vscsi->dev, "adapter_idle: flags 0x%x, state 0x%hx\n",
1318                 vscsi->flags, vscsi->state);
1319
1320         /* Only need to free qs if we're disconnecting from client */
1321         if (vscsi->state != WAIT_CONNECTION || vscsi->flags & TRANS_EVENT)
1322                 free_qs = true;
1323
1324         switch (vscsi->state) {
1325         case UNCONFIGURING:
1326                 ibmvscsis_free_command_q(vscsi);
1327                 dma_rmb();
1328                 isync();
1329                 if (vscsi->flags & CFG_SLEEPING) {
1330                         vscsi->flags &= ~CFG_SLEEPING;
1331                         complete(&vscsi->unconfig);
1332                 }
1333                 break;
1334         case ERR_DISCONNECT_RECONNECT:
1335                 ibmvscsis_reset_queue(vscsi);
1336                 dev_dbg(&vscsi->dev, "adapter_idle, disc_rec: flags 0x%x\n",
1337                         vscsi->flags);
1338                 break;
1339
1340         case ERR_DISCONNECT:
1341                 ibmvscsis_free_command_q(vscsi);
1342                 vscsi->flags &= ~(SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED);
1343                 vscsi->flags |= RESPONSE_Q_DOWN;
1344                 if (vscsi->tport.enabled)
1345                         vscsi->state = ERR_DISCONNECTED;
1346                 else
1347                         vscsi->state = WAIT_ENABLED;
1348                 dev_dbg(&vscsi->dev, "adapter_idle, disc: flags 0x%x, state 0x%hx\n",
1349                         vscsi->flags, vscsi->state);
1350                 break;
1351
1352         case WAIT_IDLE:
1353                 vscsi->rsp_q_timer.timer_pops = 0;
1354                 vscsi->debit = 0;
1355                 vscsi->credit = 0;
1356                 if (vscsi->flags & PREP_FOR_SUSPEND_PENDING) {
1357                         vscsi->state = vscsi->resume_state;
1358                         vscsi->resume_state = 0;
1359                         rc = ibmvscsis_ready_for_suspend(vscsi, true);
1360                         vscsi->flags &= ~DISCONNECT_SCHEDULED;
1361                         if (rc)
1362                                 break;
1363                 } else if (vscsi->flags & TRANS_EVENT) {
1364                         vscsi->state = WAIT_CONNECTION;
1365                         vscsi->flags &= PRESERVE_FLAG_FIELDS;
1366                 } else {
1367                         vscsi->state = CONNECTED;
1368                         vscsi->flags &= ~DISCONNECT_SCHEDULED;
1369                 }
1370
1371                 dev_dbg(&vscsi->dev, "adapter_idle, wait: flags 0x%x, state 0x%hx\n",
1372                         vscsi->flags, vscsi->state);
1373                 ibmvscsis_poll_cmd_q(vscsi);
1374                 break;
1375
1376         case ERR_DISCONNECTED:
1377                 vscsi->flags &= ~DISCONNECT_SCHEDULED;
1378                 dev_dbg(&vscsi->dev, "adapter_idle, disconnected: flags 0x%x, state 0x%hx\n",
1379                         vscsi->flags, vscsi->state);
1380                 break;
1381
1382         default:
1383                 dev_err(&vscsi->dev, "adapter_idle: in invalid state %d\n",
1384                         vscsi->state);
1385                 break;
1386         }
1387
1388         if (free_qs)
1389                 ibmvscsis_free_cmd_qs(vscsi);
1390
1391         /*
1392          * There is a timing window where we could lose a disconnect request.
1393          * The known path to this window occurs during the DISCONNECT_RECONNECT
1394          * case above: reset_queue calls free_command_q, which will release the
1395          * interrupt lock.  During that time, a new post_disconnect call can be
1396          * made with a "more severe" state (DISCONNECT or UNCONFIGURING).
1397          * Because the DISCONNECT_SCHEDULED flag is already set, post_disconnect
1398          * will only set the new_state.  Now free_command_q reacquires the intr
1399          * lock and clears the DISCONNECT_SCHEDULED flag (using PRESERVE_FLAG_
1400          * FIELDS), and the disconnect is lost.  This is particularly bad when
1401          * the new disconnect was for UNCONFIGURING, since the unconfigure hangs
1402          * forever.
1403          * Fix is that free command queue sets acr state and acr flags if there
1404          * is a change under the lock
1405          * note free command queue writes to this state it clears it
1406          * before releasing the lock, different drivers call the free command
1407          * queue different times so dont initialize above
1408          */
1409         if (vscsi->phyp_acr_state != 0) {
1410                 /*
1411                  * set any bits in flags that may have been cleared by
1412                  * a call to free command queue in switch statement
1413                  * or reset queue
1414                  */
1415                 vscsi->flags |= vscsi->phyp_acr_flags;
1416                 ibmvscsis_post_disconnect(vscsi, vscsi->phyp_acr_state, 0);
1417                 vscsi->phyp_acr_state = 0;
1418                 vscsi->phyp_acr_flags = 0;
1419
1420                 dev_dbg(&vscsi->dev, "adapter_idle: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
1421                         vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
1422                         vscsi->phyp_acr_state);
1423         }
1424
1425         dev_dbg(&vscsi->dev, "Leaving adapter_idle: flags 0x%x, state 0x%hx, new_state 0x%x\n",
1426                 vscsi->flags, vscsi->state, vscsi->new_state);
1427 }
1428
1429 /**
1430  * ibmvscsis_copy_crq_packet() - Copy CRQ Packet
1431  * @vscsi:      Pointer to our adapter structure
1432  * @cmd:        Pointer to command element to use to process the request
1433  * @crq:        Pointer to CRQ entry containing the request
1434  *
1435  * Copy the srp information unit from the hosted
1436  * partition using remote dma
1437  *
1438  * EXECUTION ENVIRONMENT:
1439  *      Interrupt, interrupt lock held
1440  */
1441 static long ibmvscsis_copy_crq_packet(struct scsi_info *vscsi,
1442                                       struct ibmvscsis_cmd *cmd,
1443                                       struct viosrp_crq *crq)
1444 {
1445         struct iu_entry *iue = cmd->iue;
1446         long rc = 0;
1447         u16 len;
1448
1449         len = be16_to_cpu(crq->IU_length);
1450         if ((len > SRP_MAX_IU_LEN) || (len == 0)) {
1451                 dev_err(&vscsi->dev, "copy_crq: Invalid len %d passed", len);
1452                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1453                 return SRP_VIOLATION;
1454         }
1455
1456         rc = h_copy_rdma(len, vscsi->dds.window[REMOTE].liobn,
1457                          be64_to_cpu(crq->IU_data_ptr),
1458                          vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma);
1459
1460         switch (rc) {
1461         case H_SUCCESS:
1462                 cmd->init_time = mftb();
1463                 iue->remote_token = crq->IU_data_ptr;
1464                 iue->iu_len = len;
1465                 dev_dbg(&vscsi->dev, "copy_crq: ioba 0x%llx, init_time 0x%llx\n",
1466                         be64_to_cpu(crq->IU_data_ptr), cmd->init_time);
1467                 break;
1468         case H_PERMISSION:
1469                 if (connection_broken(vscsi))
1470                         ibmvscsis_post_disconnect(vscsi,
1471                                                   ERR_DISCONNECT_RECONNECT,
1472                                                   (RESPONSE_Q_DOWN |
1473                                                    CLIENT_FAILED));
1474                 else
1475                         ibmvscsis_post_disconnect(vscsi,
1476                                                   ERR_DISCONNECT_RECONNECT, 0);
1477
1478                 dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
1479                         rc);
1480                 break;
1481         case H_DEST_PARM:
1482         case H_SOURCE_PARM:
1483         default:
1484                 dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
1485                         rc);
1486                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
1487                 break;
1488         }
1489
1490         return rc;
1491 }
1492
1493 /**
1494  * ibmvscsis_adapter_info - Service an Adapter Info MAnagement Data gram
1495  * @vscsi:      Pointer to our adapter structure
1496  * @iue:        Information Unit containing the Adapter Info MAD request
1497  *
1498  * EXECUTION ENVIRONMENT:
1499  *      Interrupt adapter lock is held
1500  */
1501 static long ibmvscsis_adapter_info(struct scsi_info *vscsi,
1502                                    struct iu_entry *iue)
1503 {
1504         struct viosrp_adapter_info *mad = &vio_iu(iue)->mad.adapter_info;
1505         struct mad_adapter_info_data *info;
1506         uint flag_bits = 0;
1507         dma_addr_t token;
1508         long rc;
1509
1510         mad->common.status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1511
1512         if (be16_to_cpu(mad->common.length) > sizeof(*info)) {
1513                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1514                 return 0;
1515         }
1516
1517         info = dma_alloc_coherent(&vscsi->dma_dev->dev, sizeof(*info), &token,
1518                                   GFP_ATOMIC);
1519         if (!info) {
1520                 dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
1521                         iue->target);
1522                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1523                 return 0;
1524         }
1525
1526         /* Get remote info */
1527         rc = h_copy_rdma(be16_to_cpu(mad->common.length),
1528                          vscsi->dds.window[REMOTE].liobn,
1529                          be64_to_cpu(mad->buffer),
1530                          vscsi->dds.window[LOCAL].liobn, token);
1531
1532         if (rc != H_SUCCESS) {
1533                 if (rc == H_PERMISSION) {
1534                         if (connection_broken(vscsi))
1535                                 flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1536                 }
1537                 dev_warn(&vscsi->dev, "adapter_info: h_copy_rdma from client failed, rc %ld\n",
1538                          rc);
1539                 dev_dbg(&vscsi->dev, "adapter_info: ioba 0x%llx, flags 0x%x, flag_bits 0x%x\n",
1540                         be64_to_cpu(mad->buffer), vscsi->flags, flag_bits);
1541                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
1542                                           flag_bits);
1543                 goto free_dma;
1544         }
1545
1546         /*
1547          * Copy client info, but ignore partition number, which we
1548          * already got from phyp - unless we failed to get it from
1549          * phyp (e.g. if we're running on a p5 system).
1550          */
1551         if (vscsi->client_data.partition_number == 0)
1552                 vscsi->client_data.partition_number =
1553                         be32_to_cpu(info->partition_number);
1554         strncpy(vscsi->client_data.srp_version, info->srp_version,
1555                 sizeof(vscsi->client_data.srp_version));
1556         strncpy(vscsi->client_data.partition_name, info->partition_name,
1557                 sizeof(vscsi->client_data.partition_name));
1558         vscsi->client_data.mad_version = be32_to_cpu(info->mad_version);
1559         vscsi->client_data.os_type = be32_to_cpu(info->os_type);
1560
1561         /* Copy our info */
1562         strncpy(info->srp_version, SRP_VERSION,
1563                 sizeof(info->srp_version));
1564         strncpy(info->partition_name, vscsi->dds.partition_name,
1565                 sizeof(info->partition_name));
1566         info->partition_number = cpu_to_be32(vscsi->dds.partition_num);
1567         info->mad_version = cpu_to_be32(MAD_VERSION_1);
1568         info->os_type = cpu_to_be32(LINUX);
1569         memset(&info->port_max_txu[0], 0, sizeof(info->port_max_txu));
1570         info->port_max_txu[0] = cpu_to_be32(MAX_TXU);
1571
1572         dma_wmb();
1573         rc = h_copy_rdma(sizeof(*info), vscsi->dds.window[LOCAL].liobn,
1574                          token, vscsi->dds.window[REMOTE].liobn,
1575                          be64_to_cpu(mad->buffer));
1576         switch (rc) {
1577         case H_SUCCESS:
1578                 break;
1579
1580         case H_SOURCE_PARM:
1581         case H_DEST_PARM:
1582         case H_PERMISSION:
1583                 if (connection_broken(vscsi))
1584                         flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
1585                 fallthrough;
1586         default:
1587                 dev_err(&vscsi->dev, "adapter_info: h_copy_rdma to client failed, rc %ld\n",
1588                         rc);
1589                 ibmvscsis_post_disconnect(vscsi,
1590                                           ERR_DISCONNECT_RECONNECT,
1591                                           flag_bits);
1592                 break;
1593         }
1594
1595 free_dma:
1596         dma_free_coherent(&vscsi->dma_dev->dev, sizeof(*info), info, token);
1597         dev_dbg(&vscsi->dev, "Leaving adapter_info, rc %ld\n", rc);
1598
1599         return rc;
1600 }
1601
1602 /**
1603  * ibmvscsis_cap_mad() - Service a Capabilities MAnagement Data gram
1604  * @vscsi:      Pointer to our adapter structure
1605  * @iue:        Information Unit containing the Capabilities MAD request
1606  *
1607  * NOTE: if you return an error from this routine you must be
1608  * disconnecting or you will cause a hang
1609  *
1610  * EXECUTION ENVIRONMENT:
1611  *      Interrupt called with adapter lock held
1612  */
1613 static int ibmvscsis_cap_mad(struct scsi_info *vscsi, struct iu_entry *iue)
1614 {
1615         struct viosrp_capabilities *mad = &vio_iu(iue)->mad.capabilities;
1616         struct capabilities *cap;
1617         struct mad_capability_common *common;
1618         dma_addr_t token;
1619         u16 olen, len, status, min_len, cap_len;
1620         u32 flag;
1621         uint flag_bits = 0;
1622         long rc = 0;
1623
1624         olen = be16_to_cpu(mad->common.length);
1625         /*
1626          * struct capabilities hardcodes a couple capabilities after the
1627          * header, but the capabilities can actually be in any order.
1628          */
1629         min_len = offsetof(struct capabilities, migration);
1630         if ((olen < min_len) || (olen > PAGE_SIZE)) {
1631                 dev_warn(&vscsi->dev, "cap_mad: invalid len %d\n", olen);
1632                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1633                 return 0;
1634         }
1635
1636         cap = dma_alloc_coherent(&vscsi->dma_dev->dev, olen, &token,
1637                                  GFP_ATOMIC);
1638         if (!cap) {
1639                 dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
1640                         iue->target);
1641                 mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
1642                 return 0;
1643         }
1644         rc = h_copy_rdma(olen, vscsi->dds.window[REMOTE].liobn,
1645                          be64_to_cpu(mad->buffer),
1646                          vscsi->dds.window[LOCAL].liobn, token);
1647         if (rc == H_SUCCESS) {
1648                 strncpy(cap->name, dev_name(&vscsi->dma_dev->dev),
1649                         SRP_MAX_LOC_LEN);
1650
1651                 len = olen - min_len;
1652                 status = VIOSRP_MAD_SUCCESS;
1653                 common = (struct mad_capability_common *)&cap->migration;
1654
1655                 while ((len > 0) && (status == VIOSRP_MAD_SUCCESS) && !rc) {
1656                         dev_dbg(&vscsi->dev, "cap_mad: len left %hd, cap type %d, cap len %hd\n",
1657                                 len, be32_to_cpu(common->cap_type),
1658                                 be16_to_cpu(common->length));
1659
1660                         cap_len = be16_to_cpu(common->length);
1661                         if (cap_len > len) {
1662                                 dev_err(&vscsi->dev, "cap_mad: cap len mismatch with total len\n");
1663                                 status = VIOSRP_MAD_FAILED;
1664                                 break;
1665                         }
1666
1667                         if (cap_len == 0) {
1668                                 dev_err(&vscsi->dev, "cap_mad: cap len is 0\n");
1669                                 status = VIOSRP_MAD_FAILED;
1670                                 break;
1671                         }
1672
1673                         switch (common->cap_type) {
1674                         default:
1675                                 dev_dbg(&vscsi->dev, "cap_mad: unsupported capability\n");
1676                                 common->server_support = 0;
1677                                 flag = cpu_to_be32((u32)CAP_LIST_SUPPORTED);
1678                                 cap->flags &= ~flag;
1679                                 break;
1680                         }
1681
1682                         len = len - cap_len;
1683                         common = (struct mad_capability_common *)
1684                                 ((char *)common + cap_len);
1685                 }
1686
1687                 mad->common.status = cpu_to_be16(status);
1688
1689                 dma_wmb();
1690                 rc = h_copy_rdma(olen, vscsi->dds.window[LOCAL].liobn, token,
1691                                  vscsi->dds.window[REMOTE].liobn,
1692                                  be64_to_cpu(mad->buffer));
1693
1694                 if (rc != H_SUCCESS) {
1695                         dev_dbg(&vscsi->dev, "cap_mad: failed to copy to client, rc %ld\n",
1696                                 rc);
1697
1698                         if (rc == H_PERMISSION) {
1699                                 if (connection_broken(vscsi))
1700                                         flag_bits = (RESPONSE_Q_DOWN |
1701                                                      CLIENT_FAILED);
1702                         }
1703
1704                         dev_warn(&vscsi->dev, "cap_mad: error copying data to client, rc %ld\n",
1705                                  rc);
1706                         ibmvscsis_post_disconnect(vscsi,
1707                                                   ERR_DISCONNECT_RECONNECT,
1708                                                   flag_bits);
1709                 }
1710         }
1711
1712         dma_free_coherent(&vscsi->dma_dev->dev, olen, cap, token);
1713
1714         dev_dbg(&vscsi->dev, "Leaving cap_mad, rc %ld, client_cap 0x%x\n",
1715                 rc, vscsi->client_cap);
1716
1717         return rc;
1718 }
1719
1720 /**
1721  * ibmvscsis_process_mad() - Service a MAnagement Data gram
1722  * @vscsi:      Pointer to our adapter structure
1723  * @iue:        Information Unit containing the MAD request
1724  *
1725  * Must be called with interrupt lock held.
1726  */
1727 static long ibmvscsis_process_mad(struct scsi_info *vscsi, struct iu_entry *iue)
1728 {
1729         struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
1730         struct viosrp_empty_iu *empty;
1731         long rc = ADAPT_SUCCESS;
1732
1733         switch (be32_to_cpu(mad->type)) {
1734         case VIOSRP_EMPTY_IU_TYPE:
1735                 empty = &vio_iu(iue)->mad.empty_iu;
1736                 vscsi->empty_iu_id = be64_to_cpu(empty->buffer);
1737                 vscsi->empty_iu_tag = be64_to_cpu(empty->common.tag);
1738                 mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1739                 break;
1740         case VIOSRP_ADAPTER_INFO_TYPE:
1741                 rc = ibmvscsis_adapter_info(vscsi, iue);
1742                 break;
1743         case VIOSRP_CAPABILITIES_TYPE:
1744                 rc = ibmvscsis_cap_mad(vscsi, iue);
1745                 break;
1746         case VIOSRP_ENABLE_FAST_FAIL:
1747                 if (vscsi->state == CONNECTED) {
1748                         vscsi->fast_fail = true;
1749                         mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
1750                 } else {
1751                         dev_warn(&vscsi->dev, "fast fail mad sent after login\n");
1752                         mad->status = cpu_to_be16(VIOSRP_MAD_FAILED);
1753                 }
1754                 break;
1755         default:
1756                 mad->status = cpu_to_be16(VIOSRP_MAD_NOT_SUPPORTED);
1757                 break;
1758         }
1759
1760         return rc;
1761 }
1762
1763 /**
1764  * srp_snd_msg_failed() - Handle an error when sending a response
1765  * @vscsi:      Pointer to our adapter structure
1766  * @rc:         The return code from the h_send_crq command
1767  *
1768  * Must be called with interrupt lock held.
1769  */
1770 static void srp_snd_msg_failed(struct scsi_info *vscsi, long rc)
1771 {
1772         ktime_t kt;
1773
1774         if (rc != H_DROPPED) {
1775                 ibmvscsis_free_cmd_qs(vscsi);
1776
1777                 if (rc == H_CLOSED)
1778                         vscsi->flags |= CLIENT_FAILED;
1779
1780                 /* don't flag the same problem multiple times */
1781                 if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
1782                         vscsi->flags |= RESPONSE_Q_DOWN;
1783                         if (!(vscsi->state & (ERR_DISCONNECT |
1784                                               ERR_DISCONNECT_RECONNECT |
1785                                               ERR_DISCONNECTED | UNDEFINED))) {
1786                                 dev_err(&vscsi->dev, "snd_msg_failed: setting RESPONSE_Q_DOWN, state 0x%hx, flags 0x%x, rc %ld\n",
1787                                         vscsi->state, vscsi->flags, rc);
1788                         }
1789                         ibmvscsis_post_disconnect(vscsi,
1790                                                   ERR_DISCONNECT_RECONNECT, 0);
1791                 }
1792                 return;
1793         }
1794
1795         /*
1796          * The response queue is full.
1797          * If the server is processing SRP requests, i.e.
1798          * the client has successfully done an
1799          * SRP_LOGIN, then it will wait forever for room in
1800          * the queue.  However if the system admin
1801          * is attempting to unconfigure the server then one
1802          * or more children will be in a state where
1803          * they are being removed. So if there is even one
1804          * child being removed then the driver assumes
1805          * the system admin is attempting to break the
1806          * connection with the client and MAX_TIMER_POPS
1807          * is honored.
1808          */
1809         if ((vscsi->rsp_q_timer.timer_pops < MAX_TIMER_POPS) ||
1810             (vscsi->state == SRP_PROCESSING)) {
1811                 dev_dbg(&vscsi->dev, "snd_msg_failed: response queue full, flags 0x%x, timer started %d, pops %d\n",
1812                         vscsi->flags, (int)vscsi->rsp_q_timer.started,
1813                         vscsi->rsp_q_timer.timer_pops);
1814
1815                 /*
1816                  * Check if the timer is running; if it
1817                  * is not then start it up.
1818                  */
1819                 if (!vscsi->rsp_q_timer.started) {
1820                         if (vscsi->rsp_q_timer.timer_pops <
1821                             MAX_TIMER_POPS) {
1822                                 kt = WAIT_NANO_SECONDS;
1823                         } else {
1824                                 /*
1825                                  * slide the timeslice if the maximum
1826                                  * timer pops have already happened
1827                                  */
1828                                 kt = ktime_set(WAIT_SECONDS, 0);
1829                         }
1830
1831                         vscsi->rsp_q_timer.started = true;
1832                         hrtimer_start(&vscsi->rsp_q_timer.timer, kt,
1833                                       HRTIMER_MODE_REL);
1834                 }
1835         } else {
1836                 /*
1837                  * TBD: Do we need to worry about this? Need to get
1838                  *      remove working.
1839                  */
1840                 /*
1841                  * waited a long time and it appears the system admin
1842                  * is bring this driver down
1843                  */
1844                 vscsi->flags |= RESPONSE_Q_DOWN;
1845                 ibmvscsis_free_cmd_qs(vscsi);
1846                 /*
1847                  * if the driver is already attempting to disconnect
1848                  * from the client and has already logged an error
1849                  * trace this event but don't put it in the error log
1850                  */
1851                 if (!(vscsi->state & (ERR_DISCONNECT |
1852                                       ERR_DISCONNECT_RECONNECT |
1853                                       ERR_DISCONNECTED | UNDEFINED))) {
1854                         dev_err(&vscsi->dev, "client crq full too long\n");
1855                         ibmvscsis_post_disconnect(vscsi,
1856                                                   ERR_DISCONNECT_RECONNECT,
1857                                                   0);
1858                 }
1859         }
1860 }
1861
1862 /**
1863  * ibmvscsis_send_messages() - Send a Response
1864  * @vscsi:      Pointer to our adapter structure
1865  *
1866  * Send a response, first checking the waiting queue. Responses are
1867  * sent in order they are received. If the response cannot be sent,
1868  * because the client queue is full, it stays on the waiting queue.
1869  *
1870  * PRECONDITION:
1871  *      Called with interrupt lock held
1872  */
1873 static void ibmvscsis_send_messages(struct scsi_info *vscsi)
1874 {
1875         struct viosrp_crq empty_crq = { };
1876         struct viosrp_crq *crq = &empty_crq;
1877         struct ibmvscsis_cmd *cmd, *nxt;
1878         long rc = ADAPT_SUCCESS;
1879         bool retry = false;
1880
1881         if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
1882                 do {
1883                         retry = false;
1884                         list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp,
1885                                                  list) {
1886                                 /*
1887                                  * Check to make sure abort cmd gets processed
1888                                  * prior to the abort tmr cmd
1889                                  */
1890                                 if (cmd->flags & DELAY_SEND)
1891                                         continue;
1892
1893                                 if (cmd->abort_cmd) {
1894                                         retry = true;
1895                                         cmd->abort_cmd->flags &= ~(DELAY_SEND);
1896                                         cmd->abort_cmd = NULL;
1897                                 }
1898
1899                                 /*
1900                                  * If CMD_T_ABORTED w/o CMD_T_TAS scenarios and
1901                                  * the case where LIO issued a
1902                                  * ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST
1903                                  * case then we dont send a response, since it
1904                                  * was already done.
1905                                  */
1906                                 if (cmd->se_cmd.transport_state & CMD_T_ABORTED &&
1907                                     !(cmd->se_cmd.transport_state & CMD_T_TAS)) {
1908                                         list_del(&cmd->list);
1909                                         ibmvscsis_free_cmd_resources(vscsi,
1910                                                                      cmd);
1911                                         /*
1912                                          * With a successfully aborted op
1913                                          * through LIO we want to increment the
1914                                          * the vscsi credit so that when we dont
1915                                          * send a rsp to the original scsi abort
1916                                          * op (h_send_crq), but the tm rsp to
1917                                          * the abort is sent, the credit is
1918                                          * correctly sent with the abort tm rsp.
1919                                          * We would need 1 for the abort tm rsp
1920                                          * and 1 credit for the aborted scsi op.
1921                                          * Thus we need to increment here.
1922                                          * Also we want to increment the credit
1923                                          * here because we want to make sure
1924                                          * cmd is actually released first
1925                                          * otherwise the client will think it
1926                                          * it can send a new cmd, and we could
1927                                          * find ourselves short of cmd elements.
1928                                          */
1929                                         vscsi->credit += 1;
1930                                 } else {
1931                                         crq->valid = VALID_CMD_RESP_EL;
1932                                         crq->format = cmd->rsp.format;
1933
1934                                         if (cmd->flags & CMD_FAST_FAIL)
1935                                                 crq->status = VIOSRP_ADAPTER_FAIL;
1936
1937                                         crq->IU_length = cpu_to_be16(cmd->rsp.len);
1938
1939                                         rc = h_send_crq(vscsi->dma_dev->unit_address,
1940                                                         be64_to_cpu(crq->high),
1941                                                         be64_to_cpu(cmd->rsp.tag));
1942
1943                                         dev_dbg(&vscsi->dev, "send_messages: cmd %p, tag 0x%llx, rc %ld\n",
1944                                                 cmd, be64_to_cpu(cmd->rsp.tag),
1945                                                 rc);
1946
1947                                         /* if all ok free up the command
1948                                          * element resources
1949                                          */
1950                                         if (rc == H_SUCCESS) {
1951                                                 /* some movement has occurred */
1952                                                 vscsi->rsp_q_timer.timer_pops = 0;
1953                                                 list_del(&cmd->list);
1954
1955                                                 ibmvscsis_free_cmd_resources(vscsi,
1956                                                                              cmd);
1957                                         } else {
1958                                                 srp_snd_msg_failed(vscsi, rc);
1959                                                 break;
1960                                         }
1961                                 }
1962                         }
1963                 } while (retry);
1964
1965                 if (!rc) {
1966                         /*
1967                          * The timer could pop with the queue empty.  If
1968                          * this happens, rc will always indicate a
1969                          * success; clear the pop count.
1970                          */
1971                         vscsi->rsp_q_timer.timer_pops = 0;
1972                 }
1973         } else {
1974                 ibmvscsis_free_cmd_qs(vscsi);
1975         }
1976 }
1977
1978 /* Called with intr lock held */
1979 static void ibmvscsis_send_mad_resp(struct scsi_info *vscsi,
1980                                     struct ibmvscsis_cmd *cmd,
1981                                     struct viosrp_crq *crq)
1982 {
1983         struct iu_entry *iue = cmd->iue;
1984         struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
1985         uint flag_bits = 0;
1986         long rc;
1987
1988         dma_wmb();
1989         rc = h_copy_rdma(sizeof(struct mad_common),
1990                          vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
1991                          vscsi->dds.window[REMOTE].liobn,
1992                          be64_to_cpu(crq->IU_data_ptr));
1993         if (!rc) {
1994                 cmd->rsp.format = VIOSRP_MAD_FORMAT;
1995                 cmd->rsp.len = sizeof(struct mad_common);
1996                 cmd->rsp.tag = mad->tag;
1997                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
1998                 ibmvscsis_send_messages(vscsi);
1999         } else {
2000                 dev_dbg(&vscsi->dev, "Error sending mad response, rc %ld\n",
2001                         rc);
2002                 if (rc == H_PERMISSION) {
2003                         if (connection_broken(vscsi))
2004                                 flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
2005                 }
2006                 dev_err(&vscsi->dev, "mad: failed to copy to client, rc %ld\n",
2007                         rc);
2008
2009                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2010                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
2011                                           flag_bits);
2012         }
2013 }
2014
2015 /**
2016  * ibmvscsis_mad() - Service a MAnagement Data gram.
2017  * @vscsi:      Pointer to our adapter structure
2018  * @crq:        Pointer to the CRQ entry containing the MAD request
2019  *
2020  * EXECUTION ENVIRONMENT:
2021  *      Interrupt, called with adapter lock held
2022  */
2023 static long ibmvscsis_mad(struct scsi_info *vscsi, struct viosrp_crq *crq)
2024 {
2025         struct iu_entry *iue;
2026         struct ibmvscsis_cmd *cmd;
2027         struct mad_common *mad;
2028         long rc = ADAPT_SUCCESS;
2029
2030         switch (vscsi->state) {
2031                 /*
2032                  * We have not exchanged Init Msgs yet, so this MAD was sent
2033                  * before the last Transport Event; client will not be
2034                  * expecting a response.
2035                  */
2036         case WAIT_CONNECTION:
2037                 dev_dbg(&vscsi->dev, "mad: in Wait Connection state, ignoring MAD, flags %d\n",
2038                         vscsi->flags);
2039                 return ADAPT_SUCCESS;
2040
2041         case SRP_PROCESSING:
2042         case CONNECTED:
2043                 break;
2044
2045                 /*
2046                  * We should never get here while we're in these states.
2047                  * Just log an error and get out.
2048                  */
2049         case UNCONFIGURING:
2050         case WAIT_IDLE:
2051         case ERR_DISCONNECT:
2052         case ERR_DISCONNECT_RECONNECT:
2053         default:
2054                 dev_err(&vscsi->dev, "mad: invalid adapter state %d for mad\n",
2055                         vscsi->state);
2056                 return ADAPT_SUCCESS;
2057         }
2058
2059         cmd = ibmvscsis_get_free_cmd(vscsi);
2060         if (!cmd) {
2061                 dev_err(&vscsi->dev, "mad: failed to get cmd, debit %d\n",
2062                         vscsi->debit);
2063                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2064                 return ERROR;
2065         }
2066         iue = cmd->iue;
2067         cmd->type = ADAPTER_MAD;
2068
2069         rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
2070         if (!rc) {
2071                 mad = (struct mad_common *)&vio_iu(iue)->mad;
2072
2073                 dev_dbg(&vscsi->dev, "mad: type %d\n", be32_to_cpu(mad->type));
2074
2075                 rc = ibmvscsis_process_mad(vscsi, iue);
2076
2077                 dev_dbg(&vscsi->dev, "mad: status %hd, rc %ld\n",
2078                         be16_to_cpu(mad->status), rc);
2079
2080                 if (!rc)
2081                         ibmvscsis_send_mad_resp(vscsi, cmd, crq);
2082         } else {
2083                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2084         }
2085
2086         dev_dbg(&vscsi->dev, "Leaving mad, rc %ld\n", rc);
2087         return rc;
2088 }
2089
2090 /**
2091  * ibmvscsis_login_rsp() - Create/copy a login response notice to the client
2092  * @vscsi:      Pointer to our adapter structure
2093  * @cmd:        Pointer to the command for the SRP Login request
2094  *
2095  * EXECUTION ENVIRONMENT:
2096  *      Interrupt, interrupt lock held
2097  */
2098 static long ibmvscsis_login_rsp(struct scsi_info *vscsi,
2099                                 struct ibmvscsis_cmd *cmd)
2100 {
2101         struct iu_entry *iue = cmd->iue;
2102         struct srp_login_rsp *rsp = &vio_iu(iue)->srp.login_rsp;
2103         struct format_code *fmt;
2104         uint flag_bits = 0;
2105         long rc = ADAPT_SUCCESS;
2106
2107         memset(rsp, 0, sizeof(struct srp_login_rsp));
2108
2109         rsp->opcode = SRP_LOGIN_RSP;
2110         rsp->req_lim_delta = cpu_to_be32(vscsi->request_limit);
2111         rsp->tag = cmd->rsp.tag;
2112         rsp->max_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
2113         rsp->max_ti_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
2114         fmt = (struct format_code *)&rsp->buf_fmt;
2115         fmt->buffers = SUPPORTED_FORMATS;
2116         vscsi->credit = 0;
2117
2118         cmd->rsp.len = sizeof(struct srp_login_rsp);
2119
2120         dma_wmb();
2121         rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
2122                          iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
2123                          be64_to_cpu(iue->remote_token));
2124
2125         switch (rc) {
2126         case H_SUCCESS:
2127                 break;
2128
2129         case H_PERMISSION:
2130                 if (connection_broken(vscsi))
2131                         flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
2132                 dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
2133                         rc);
2134                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
2135                                           flag_bits);
2136                 break;
2137         case H_SOURCE_PARM:
2138         case H_DEST_PARM:
2139         default:
2140                 dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
2141                         rc);
2142                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2143                 break;
2144         }
2145
2146         return rc;
2147 }
2148
2149 /**
2150  * ibmvscsis_srp_login_rej() - Create/copy a login rejection notice to client
2151  * @vscsi:      Pointer to our adapter structure
2152  * @cmd:        Pointer to the command for the SRP Login request
2153  * @reason:     The reason the SRP Login is being rejected, per SRP protocol
2154  *
2155  * EXECUTION ENVIRONMENT:
2156  *      Interrupt, interrupt lock held
2157  */
2158 static long ibmvscsis_srp_login_rej(struct scsi_info *vscsi,
2159                                     struct ibmvscsis_cmd *cmd, u32 reason)
2160 {
2161         struct iu_entry *iue = cmd->iue;
2162         struct srp_login_rej *rej = &vio_iu(iue)->srp.login_rej;
2163         struct format_code *fmt;
2164         uint flag_bits = 0;
2165         long rc = ADAPT_SUCCESS;
2166
2167         memset(rej, 0, sizeof(*rej));
2168
2169         rej->opcode = SRP_LOGIN_REJ;
2170         rej->reason = cpu_to_be32(reason);
2171         rej->tag = cmd->rsp.tag;
2172         fmt = (struct format_code *)&rej->buf_fmt;
2173         fmt->buffers = SUPPORTED_FORMATS;
2174
2175         cmd->rsp.len = sizeof(*rej);
2176
2177         dma_wmb();
2178         rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
2179                          iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
2180                          be64_to_cpu(iue->remote_token));
2181
2182         switch (rc) {
2183         case H_SUCCESS:
2184                 break;
2185         case H_PERMISSION:
2186                 if (connection_broken(vscsi))
2187                         flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
2188                 dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
2189                         rc);
2190                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
2191                                           flag_bits);
2192                 break;
2193         case H_SOURCE_PARM:
2194         case H_DEST_PARM:
2195         default:
2196                 dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
2197                         rc);
2198                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2199                 break;
2200         }
2201
2202         return rc;
2203 }
2204
2205 static int ibmvscsis_make_nexus(struct ibmvscsis_tport *tport)
2206 {
2207         char *name = tport->tport_name;
2208         struct ibmvscsis_nexus *nexus;
2209         struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
2210         int rc;
2211
2212         if (tport->ibmv_nexus) {
2213                 dev_dbg(&vscsi->dev, "tport->ibmv_nexus already exists\n");
2214                 return 0;
2215         }
2216
2217         nexus = kzalloc(sizeof(*nexus), GFP_KERNEL);
2218         if (!nexus) {
2219                 dev_err(&vscsi->dev, "Unable to allocate struct ibmvscsis_nexus\n");
2220                 return -ENOMEM;
2221         }
2222
2223         nexus->se_sess = target_setup_session(&tport->se_tpg, 0, 0,
2224                                               TARGET_PROT_NORMAL, name, nexus,
2225                                               NULL);
2226         if (IS_ERR(nexus->se_sess)) {
2227                 rc = PTR_ERR(nexus->se_sess);
2228                 goto transport_init_fail;
2229         }
2230
2231         tport->ibmv_nexus = nexus;
2232
2233         return 0;
2234
2235 transport_init_fail:
2236         kfree(nexus);
2237         return rc;
2238 }
2239
2240 static int ibmvscsis_drop_nexus(struct ibmvscsis_tport *tport)
2241 {
2242         struct se_session *se_sess;
2243         struct ibmvscsis_nexus *nexus;
2244
2245         nexus = tport->ibmv_nexus;
2246         if (!nexus)
2247                 return -ENODEV;
2248
2249         se_sess = nexus->se_sess;
2250         if (!se_sess)
2251                 return -ENODEV;
2252
2253         /*
2254          * Release the SCSI I_T Nexus to the emulated ibmvscsis Target Port
2255          */
2256         target_remove_session(se_sess);
2257         tport->ibmv_nexus = NULL;
2258         kfree(nexus);
2259
2260         return 0;
2261 }
2262
2263 /**
2264  * ibmvscsis_srp_login() - Process an SRP Login Request
2265  * @vscsi:      Pointer to our adapter structure
2266  * @cmd:        Command element to use to process the SRP Login request
2267  * @crq:        Pointer to CRQ entry containing the SRP Login request
2268  *
2269  * EXECUTION ENVIRONMENT:
2270  *      Interrupt, called with interrupt lock held
2271  */
2272 static long ibmvscsis_srp_login(struct scsi_info *vscsi,
2273                                 struct ibmvscsis_cmd *cmd,
2274                                 struct viosrp_crq *crq)
2275 {
2276         struct iu_entry *iue = cmd->iue;
2277         struct srp_login_req *req = &vio_iu(iue)->srp.login_req;
2278         struct port_id {
2279                 __be64 id_extension;
2280                 __be64 io_guid;
2281         } *iport, *tport;
2282         struct format_code *fmt;
2283         u32 reason = 0x0;
2284         long rc = ADAPT_SUCCESS;
2285
2286         iport = (struct port_id *)req->initiator_port_id;
2287         tport = (struct port_id *)req->target_port_id;
2288         fmt = (struct format_code *)&req->req_buf_fmt;
2289         if (be32_to_cpu(req->req_it_iu_len) > SRP_MAX_IU_LEN)
2290                 reason = SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE;
2291         else if (be32_to_cpu(req->req_it_iu_len) < 64)
2292                 reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
2293         else if ((be64_to_cpu(iport->id_extension) > (MAX_NUM_PORTS - 1)) ||
2294                  (be64_to_cpu(tport->id_extension) > (MAX_NUM_PORTS - 1)))
2295                 reason = SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL;
2296         else if (req->req_flags & SRP_MULTICHAN_MULTI)
2297                 reason = SRP_LOGIN_REJ_MULTI_CHANNEL_UNSUPPORTED;
2298         else if (fmt->buffers & (~SUPPORTED_FORMATS))
2299                 reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
2300         else if ((fmt->buffers & SUPPORTED_FORMATS) == 0)
2301                 reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
2302
2303         if (vscsi->state == SRP_PROCESSING)
2304                 reason = SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED;
2305
2306         rc = ibmvscsis_make_nexus(&vscsi->tport);
2307         if (rc)
2308                 reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
2309
2310         cmd->rsp.format = VIOSRP_SRP_FORMAT;
2311         cmd->rsp.tag = req->tag;
2312
2313         dev_dbg(&vscsi->dev, "srp_login: reason 0x%x\n", reason);
2314
2315         if (reason)
2316                 rc = ibmvscsis_srp_login_rej(vscsi, cmd, reason);
2317         else
2318                 rc = ibmvscsis_login_rsp(vscsi, cmd);
2319
2320         if (!rc) {
2321                 if (!reason)
2322                         vscsi->state = SRP_PROCESSING;
2323
2324                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
2325                 ibmvscsis_send_messages(vscsi);
2326         } else {
2327                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2328         }
2329
2330         dev_dbg(&vscsi->dev, "Leaving srp_login, rc %ld\n", rc);
2331         return rc;
2332 }
2333
2334 /**
2335  * ibmvscsis_srp_i_logout() - Helper Function to close I_T Nexus
2336  * @vscsi:      Pointer to our adapter structure
2337  * @cmd:        Command element to use to process the Implicit Logout request
2338  * @crq:        Pointer to CRQ entry containing the Implicit Logout request
2339  *
2340  * Do the logic to close the I_T nexus.  This function may not
2341  * behave to specification.
2342  *
2343  * EXECUTION ENVIRONMENT:
2344  *      Interrupt, interrupt lock held
2345  */
2346 static long ibmvscsis_srp_i_logout(struct scsi_info *vscsi,
2347                                    struct ibmvscsis_cmd *cmd,
2348                                    struct viosrp_crq *crq)
2349 {
2350         struct iu_entry *iue = cmd->iue;
2351         struct srp_i_logout *log_out = &vio_iu(iue)->srp.i_logout;
2352
2353         if ((vscsi->debit > 0) || !list_empty(&vscsi->schedule_q) ||
2354             !list_empty(&vscsi->waiting_rsp)) {
2355                 dev_err(&vscsi->dev, "i_logout: outstanding work\n");
2356                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
2357         } else {
2358                 cmd->rsp.format = SRP_FORMAT;
2359                 cmd->rsp.tag = log_out->tag;
2360                 cmd->rsp.len = sizeof(struct mad_common);
2361                 list_add_tail(&cmd->list, &vscsi->waiting_rsp);
2362                 ibmvscsis_send_messages(vscsi);
2363
2364                 ibmvscsis_post_disconnect(vscsi, WAIT_IDLE, 0);
2365         }
2366
2367         return ADAPT_SUCCESS;
2368 }
2369
2370 /* Called with intr lock held */
2371 static void ibmvscsis_srp_cmd(struct scsi_info *vscsi, struct viosrp_crq *crq)
2372 {
2373         struct ibmvscsis_cmd *cmd;
2374         struct iu_entry *iue;
2375         struct srp_cmd *srp;
2376         struct srp_tsk_mgmt *tsk;
2377         long rc;
2378
2379         if (vscsi->request_limit - vscsi->debit <= 0) {
2380                 /* Client has exceeded request limit */
2381                 dev_err(&vscsi->dev, "Client exceeded the request limit (%d), debit %d\n",
2382                         vscsi->request_limit, vscsi->debit);
2383                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2384                 return;
2385         }
2386
2387         cmd = ibmvscsis_get_free_cmd(vscsi);
2388         if (!cmd) {
2389                 dev_err(&vscsi->dev, "srp_cmd failed to get cmd, debit %d\n",
2390                         vscsi->debit);
2391                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2392                 return;
2393         }
2394         iue = cmd->iue;
2395         srp = &vio_iu(iue)->srp.cmd;
2396
2397         rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
2398         if (rc) {
2399                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2400                 return;
2401         }
2402
2403         if (vscsi->state == SRP_PROCESSING) {
2404                 switch (srp->opcode) {
2405                 case SRP_LOGIN_REQ:
2406                         rc = ibmvscsis_srp_login(vscsi, cmd, crq);
2407                         break;
2408
2409                 case SRP_TSK_MGMT:
2410                         tsk = &vio_iu(iue)->srp.tsk_mgmt;
2411                         dev_dbg(&vscsi->dev, "tsk_mgmt tag: %llu (0x%llx)\n",
2412                                 tsk->tag, tsk->tag);
2413                         cmd->rsp.tag = tsk->tag;
2414                         vscsi->debit += 1;
2415                         cmd->type = TASK_MANAGEMENT;
2416                         list_add_tail(&cmd->list, &vscsi->schedule_q);
2417                         queue_work(vscsi->work_q, &cmd->work);
2418                         break;
2419
2420                 case SRP_CMD:
2421                         dev_dbg(&vscsi->dev, "srp_cmd tag: %llu (0x%llx)\n",
2422                                 srp->tag, srp->tag);
2423                         cmd->rsp.tag = srp->tag;
2424                         vscsi->debit += 1;
2425                         cmd->type = SCSI_CDB;
2426                         /*
2427                          * We want to keep track of work waiting for
2428                          * the workqueue.
2429                          */
2430                         list_add_tail(&cmd->list, &vscsi->schedule_q);
2431                         queue_work(vscsi->work_q, &cmd->work);
2432                         break;
2433
2434                 case SRP_I_LOGOUT:
2435                         rc = ibmvscsis_srp_i_logout(vscsi, cmd, crq);
2436                         break;
2437
2438                 case SRP_CRED_RSP:
2439                 case SRP_AER_RSP:
2440                 default:
2441                         ibmvscsis_free_cmd_resources(vscsi, cmd);
2442                         dev_err(&vscsi->dev, "invalid srp cmd, opcode %d\n",
2443                                 (uint)srp->opcode);
2444                         ibmvscsis_post_disconnect(vscsi,
2445                                                   ERR_DISCONNECT_RECONNECT, 0);
2446                         break;
2447                 }
2448         } else if (srp->opcode == SRP_LOGIN_REQ && vscsi->state == CONNECTED) {
2449                 rc = ibmvscsis_srp_login(vscsi, cmd, crq);
2450         } else {
2451                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2452                 dev_err(&vscsi->dev, "Invalid state %d to handle srp cmd\n",
2453                         vscsi->state);
2454                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2455         }
2456 }
2457
2458 /**
2459  * ibmvscsis_ping_response() - Respond to a ping request
2460  * @vscsi:      Pointer to our adapter structure
2461  *
2462  * Let the client know that the server is alive and waiting on
2463  * its native I/O stack.
2464  * If any type of error occurs from the call to queue a ping
2465  * response then the client is either not accepting or receiving
2466  * interrupts.  Disconnect with an error.
2467  *
2468  * EXECUTION ENVIRONMENT:
2469  *      Interrupt, interrupt lock held
2470  */
2471 static long ibmvscsis_ping_response(struct scsi_info *vscsi)
2472 {
2473         struct viosrp_crq *crq;
2474         u64 buffer[2] = { 0, 0 };
2475         long rc;
2476
2477         crq = (struct viosrp_crq *)&buffer;
2478         crq->valid = VALID_CMD_RESP_EL;
2479         crq->format = (u8)MESSAGE_IN_CRQ;
2480         crq->status = PING_RESPONSE;
2481
2482         rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
2483                         cpu_to_be64(buffer[MSG_LOW]));
2484
2485         switch (rc) {
2486         case H_SUCCESS:
2487                 break;
2488         case H_CLOSED:
2489                 vscsi->flags |= CLIENT_FAILED;
2490                 fallthrough;
2491         case H_DROPPED:
2492                 vscsi->flags |= RESPONSE_Q_DOWN;
2493                 fallthrough;
2494         case H_REMOTE_PARM:
2495                 dev_err(&vscsi->dev, "ping_response: h_send_crq failed, rc %ld\n",
2496                         rc);
2497                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2498                 break;
2499         default:
2500                 dev_err(&vscsi->dev, "ping_response: h_send_crq returned unknown rc %ld\n",
2501                         rc);
2502                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
2503                 break;
2504         }
2505
2506         return rc;
2507 }
2508
2509 /**
2510  * ibmvscsis_parse_command() - Parse an element taken from the cmd rsp queue.
2511  * @vscsi:      Pointer to our adapter structure
2512  * @crq:        Pointer to CRQ element containing the SRP request
2513  *
2514  * This function will return success if the command queue element is valid
2515  * and the srp iu or MAD request it pointed to was also valid.  That does
2516  * not mean that an error was not returned to the client.
2517  *
2518  * EXECUTION ENVIRONMENT:
2519  *      Interrupt, intr lock held
2520  */
2521 static long ibmvscsis_parse_command(struct scsi_info *vscsi,
2522                                     struct viosrp_crq *crq)
2523 {
2524         long rc = ADAPT_SUCCESS;
2525
2526         switch (crq->valid) {
2527         case VALID_CMD_RESP_EL:
2528                 switch (crq->format) {
2529                 case OS400_FORMAT:
2530                 case AIX_FORMAT:
2531                 case LINUX_FORMAT:
2532                 case MAD_FORMAT:
2533                         if (vscsi->flags & PROCESSING_MAD) {
2534                                 rc = ERROR;
2535                                 dev_err(&vscsi->dev, "parse_command: already processing mad\n");
2536                                 ibmvscsis_post_disconnect(vscsi,
2537                                                        ERR_DISCONNECT_RECONNECT,
2538                                                        0);
2539                         } else {
2540                                 vscsi->flags |= PROCESSING_MAD;
2541                                 rc = ibmvscsis_mad(vscsi, crq);
2542                         }
2543                         break;
2544
2545                 case SRP_FORMAT:
2546                         ibmvscsis_srp_cmd(vscsi, crq);
2547                         break;
2548
2549                 case MESSAGE_IN_CRQ:
2550                         if (crq->status == PING)
2551                                 ibmvscsis_ping_response(vscsi);
2552                         break;
2553
2554                 default:
2555                         dev_err(&vscsi->dev, "parse_command: invalid format %d\n",
2556                                 (uint)crq->format);
2557                         ibmvscsis_post_disconnect(vscsi,
2558                                                   ERR_DISCONNECT_RECONNECT, 0);
2559                         break;
2560                 }
2561                 break;
2562
2563         case VALID_TRANS_EVENT:
2564                 rc = ibmvscsis_trans_event(vscsi, crq);
2565                 break;
2566
2567         case VALID_INIT_MSG:
2568                 rc = ibmvscsis_init_msg(vscsi, crq);
2569                 break;
2570
2571         default:
2572                 dev_err(&vscsi->dev, "parse_command: invalid valid field %d\n",
2573                         (uint)crq->valid);
2574                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2575                 break;
2576         }
2577
2578         /*
2579          * Return only what the interrupt handler cares
2580          * about. Most errors we keep right on trucking.
2581          */
2582         rc = vscsi->flags & SCHEDULE_DISCONNECT;
2583
2584         return rc;
2585 }
2586
2587 static int read_dma_window(struct scsi_info *vscsi)
2588 {
2589         struct vio_dev *vdev = vscsi->dma_dev;
2590         const __be32 *dma_window;
2591         const __be32 *prop;
2592
2593         /* TODO Using of_parse_dma_window would be better, but it doesn't give
2594          * a way to read multiple windows without already knowing the size of
2595          * a window or the number of windows.
2596          */
2597         dma_window = (const __be32 *)vio_get_attribute(vdev,
2598                                                        "ibm,my-dma-window",
2599                                                        NULL);
2600         if (!dma_window) {
2601                 dev_err(&vscsi->dev, "Couldn't find ibm,my-dma-window property\n");
2602                 return -1;
2603         }
2604
2605         vscsi->dds.window[LOCAL].liobn = be32_to_cpu(*dma_window);
2606         dma_window++;
2607
2608         prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-address-cells",
2609                                                  NULL);
2610         if (!prop) {
2611                 dev_warn(&vscsi->dev, "Couldn't find ibm,#dma-address-cells property\n");
2612                 dma_window++;
2613         } else {
2614                 dma_window += be32_to_cpu(*prop);
2615         }
2616
2617         prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-size-cells",
2618                                                  NULL);
2619         if (!prop) {
2620                 dev_warn(&vscsi->dev, "Couldn't find ibm,#dma-size-cells property\n");
2621                 dma_window++;
2622         } else {
2623                 dma_window += be32_to_cpu(*prop);
2624         }
2625
2626         /* dma_window should point to the second window now */
2627         vscsi->dds.window[REMOTE].liobn = be32_to_cpu(*dma_window);
2628
2629         return 0;
2630 }
2631
2632 static struct ibmvscsis_tport *ibmvscsis_lookup_port(const char *name)
2633 {
2634         struct ibmvscsis_tport *tport = NULL;
2635         struct vio_dev *vdev;
2636         struct scsi_info *vscsi;
2637
2638         spin_lock_bh(&ibmvscsis_dev_lock);
2639         list_for_each_entry(vscsi, &ibmvscsis_dev_list, list) {
2640                 vdev = vscsi->dma_dev;
2641                 if (!strcmp(dev_name(&vdev->dev), name)) {
2642                         tport = &vscsi->tport;
2643                         break;
2644                 }
2645         }
2646         spin_unlock_bh(&ibmvscsis_dev_lock);
2647
2648         return tport;
2649 }
2650
2651 /**
2652  * ibmvscsis_parse_cmd() - Parse SRP Command
2653  * @vscsi:      Pointer to our adapter structure
2654  * @cmd:        Pointer to command element with SRP command
2655  *
2656  * Parse the srp command; if it is valid then submit it to tcm.
2657  * Note: The return code does not reflect the status of the SCSI CDB.
2658  *
2659  * EXECUTION ENVIRONMENT:
2660  *      Process level
2661  */
2662 static void ibmvscsis_parse_cmd(struct scsi_info *vscsi,
2663                                 struct ibmvscsis_cmd *cmd)
2664 {
2665         struct iu_entry *iue = cmd->iue;
2666         struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
2667         struct ibmvscsis_nexus *nexus;
2668         u64 data_len = 0;
2669         enum dma_data_direction dir;
2670         int attr = 0;
2671
2672         nexus = vscsi->tport.ibmv_nexus;
2673         /*
2674          * additional length in bytes.  Note that the SRP spec says that
2675          * additional length is in 4-byte words, but technically the
2676          * additional length field is only the upper 6 bits of the byte.
2677          * The lower 2 bits are reserved.  If the lower 2 bits are 0 (as
2678          * all reserved fields should be), then interpreting the byte as
2679          * an int will yield the length in bytes.
2680          */
2681         if (srp->add_cdb_len & 0x03) {
2682                 dev_err(&vscsi->dev, "parse_cmd: reserved bits set in IU\n");
2683                 spin_lock_bh(&vscsi->intr_lock);
2684                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2685                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2686                 spin_unlock_bh(&vscsi->intr_lock);
2687                 return;
2688         }
2689
2690         if (srp_get_desc_table(srp, &dir, &data_len)) {
2691                 dev_err(&vscsi->dev, "0x%llx: parsing SRP descriptor table failed.\n",
2692                         srp->tag);
2693                 goto fail;
2694         }
2695
2696         cmd->rsp.sol_not = srp->sol_not;
2697
2698         switch (srp->task_attr) {
2699         case SRP_SIMPLE_TASK:
2700                 attr = TCM_SIMPLE_TAG;
2701                 break;
2702         case SRP_ORDERED_TASK:
2703                 attr = TCM_ORDERED_TAG;
2704                 break;
2705         case SRP_HEAD_TASK:
2706                 attr = TCM_HEAD_TAG;
2707                 break;
2708         case SRP_ACA_TASK:
2709                 attr = TCM_ACA_TAG;
2710                 break;
2711         default:
2712                 dev_err(&vscsi->dev, "Invalid task attribute %d\n",
2713                         srp->task_attr);
2714                 goto fail;
2715         }
2716
2717         cmd->se_cmd.tag = be64_to_cpu(srp->tag);
2718
2719         spin_lock_bh(&vscsi->intr_lock);
2720         list_add_tail(&cmd->list, &vscsi->active_q);
2721         spin_unlock_bh(&vscsi->intr_lock);
2722
2723         srp->lun.scsi_lun[0] &= 0x3f;
2724
2725         target_submit_cmd(&cmd->se_cmd, nexus->se_sess, srp->cdb,
2726                           cmd->sense_buf, scsilun_to_int(&srp->lun),
2727                           data_len, attr, dir, 0);
2728         return;
2729
2730 fail:
2731         spin_lock_bh(&vscsi->intr_lock);
2732         ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
2733         spin_unlock_bh(&vscsi->intr_lock);
2734 }
2735
2736 /**
2737  * ibmvscsis_parse_task() - Parse SRP Task Management Request
2738  * @vscsi:      Pointer to our adapter structure
2739  * @cmd:        Pointer to command element with SRP task management request
2740  *
2741  * Parse the srp task management request; if it is valid then submit it to tcm.
2742  * Note: The return code does not reflect the status of the task management
2743  * request.
2744  *
2745  * EXECUTION ENVIRONMENT:
2746  *      Processor level
2747  */
2748 static void ibmvscsis_parse_task(struct scsi_info *vscsi,
2749                                  struct ibmvscsis_cmd *cmd)
2750 {
2751         struct iu_entry *iue = cmd->iue;
2752         struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
2753         int tcm_type;
2754         u64 tag_to_abort = 0;
2755         int rc = 0;
2756         struct ibmvscsis_nexus *nexus;
2757
2758         nexus = vscsi->tport.ibmv_nexus;
2759
2760         cmd->rsp.sol_not = srp_tsk->sol_not;
2761
2762         switch (srp_tsk->tsk_mgmt_func) {
2763         case SRP_TSK_ABORT_TASK:
2764                 tcm_type = TMR_ABORT_TASK;
2765                 tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
2766                 break;
2767         case SRP_TSK_ABORT_TASK_SET:
2768                 tcm_type = TMR_ABORT_TASK_SET;
2769                 break;
2770         case SRP_TSK_CLEAR_TASK_SET:
2771                 tcm_type = TMR_CLEAR_TASK_SET;
2772                 break;
2773         case SRP_TSK_LUN_RESET:
2774                 tcm_type = TMR_LUN_RESET;
2775                 break;
2776         case SRP_TSK_CLEAR_ACA:
2777                 tcm_type = TMR_CLEAR_ACA;
2778                 break;
2779         default:
2780                 dev_err(&vscsi->dev, "unknown task mgmt func %d\n",
2781                         srp_tsk->tsk_mgmt_func);
2782                 cmd->se_cmd.se_tmr_req->response =
2783                         TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2784                 rc = -1;
2785                 break;
2786         }
2787
2788         if (!rc) {
2789                 cmd->se_cmd.tag = be64_to_cpu(srp_tsk->tag);
2790
2791                 spin_lock_bh(&vscsi->intr_lock);
2792                 list_add_tail(&cmd->list, &vscsi->active_q);
2793                 spin_unlock_bh(&vscsi->intr_lock);
2794
2795                 srp_tsk->lun.scsi_lun[0] &= 0x3f;
2796
2797                 dev_dbg(&vscsi->dev, "calling submit_tmr, func %d\n",
2798                         srp_tsk->tsk_mgmt_func);
2799                 rc = target_submit_tmr(&cmd->se_cmd, nexus->se_sess, NULL,
2800                                        scsilun_to_int(&srp_tsk->lun), srp_tsk,
2801                                        tcm_type, GFP_KERNEL, tag_to_abort, 0);
2802                 if (rc) {
2803                         dev_err(&vscsi->dev, "target_submit_tmr failed, rc %d\n",
2804                                 rc);
2805                         spin_lock_bh(&vscsi->intr_lock);
2806                         list_del(&cmd->list);
2807                         spin_unlock_bh(&vscsi->intr_lock);
2808                         cmd->se_cmd.se_tmr_req->response =
2809                                 TMR_FUNCTION_REJECTED;
2810                 }
2811         }
2812
2813         if (rc)
2814                 transport_send_check_condition_and_sense(&cmd->se_cmd, 0, 0);
2815 }
2816
2817 static void ibmvscsis_scheduler(struct work_struct *work)
2818 {
2819         struct ibmvscsis_cmd *cmd = container_of(work, struct ibmvscsis_cmd,
2820                                                  work);
2821         struct scsi_info *vscsi = cmd->adapter;
2822
2823         spin_lock_bh(&vscsi->intr_lock);
2824
2825         /* Remove from schedule_q */
2826         list_del(&cmd->list);
2827
2828         /* Don't submit cmd if we're disconnecting */
2829         if (vscsi->flags & (SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED)) {
2830                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2831
2832                 /* ibmvscsis_disconnect might be waiting for us */
2833                 if (list_empty(&vscsi->active_q) &&
2834                     list_empty(&vscsi->schedule_q) &&
2835                     (vscsi->flags & WAIT_FOR_IDLE)) {
2836                         vscsi->flags &= ~WAIT_FOR_IDLE;
2837                         complete(&vscsi->wait_idle);
2838                 }
2839
2840                 spin_unlock_bh(&vscsi->intr_lock);
2841                 return;
2842         }
2843
2844         spin_unlock_bh(&vscsi->intr_lock);
2845
2846         switch (cmd->type) {
2847         case SCSI_CDB:
2848                 ibmvscsis_parse_cmd(vscsi, cmd);
2849                 break;
2850         case TASK_MANAGEMENT:
2851                 ibmvscsis_parse_task(vscsi, cmd);
2852                 break;
2853         default:
2854                 dev_err(&vscsi->dev, "scheduler, invalid cmd type %d\n",
2855                         cmd->type);
2856                 spin_lock_bh(&vscsi->intr_lock);
2857                 ibmvscsis_free_cmd_resources(vscsi, cmd);
2858                 spin_unlock_bh(&vscsi->intr_lock);
2859                 break;
2860         }
2861 }
2862
2863 static int ibmvscsis_alloc_cmds(struct scsi_info *vscsi, int num)
2864 {
2865         struct ibmvscsis_cmd *cmd;
2866         int i;
2867
2868         INIT_LIST_HEAD(&vscsi->free_cmd);
2869         vscsi->cmd_pool = kcalloc(num, sizeof(struct ibmvscsis_cmd),
2870                                   GFP_KERNEL);
2871         if (!vscsi->cmd_pool)
2872                 return -ENOMEM;
2873
2874         for (i = 0, cmd = (struct ibmvscsis_cmd *)vscsi->cmd_pool; i < num;
2875              i++, cmd++) {
2876                 cmd->abort_cmd = NULL;
2877                 cmd->adapter = vscsi;
2878                 INIT_WORK(&cmd->work, ibmvscsis_scheduler);
2879                 list_add_tail(&cmd->list, &vscsi->free_cmd);
2880         }
2881
2882         return 0;
2883 }
2884
2885 static void ibmvscsis_free_cmds(struct scsi_info *vscsi)
2886 {
2887         kfree(vscsi->cmd_pool);
2888         vscsi->cmd_pool = NULL;
2889         INIT_LIST_HEAD(&vscsi->free_cmd);
2890 }
2891
2892 /**
2893  * ibmvscsis_service_wait_q() - Service Waiting Queue
2894  * @timer:      Pointer to timer which has expired
2895  *
2896  * This routine is called when the timer pops to service the waiting
2897  * queue. Elements on the queue have completed, their responses have been
2898  * copied to the client, but the client's response queue was full so
2899  * the queue message could not be sent. The routine grabs the proper locks
2900  * and calls send messages.
2901  *
2902  * EXECUTION ENVIRONMENT:
2903  *      called at interrupt level
2904  */
2905 static enum hrtimer_restart ibmvscsis_service_wait_q(struct hrtimer *timer)
2906 {
2907         struct timer_cb *p_timer = container_of(timer, struct timer_cb, timer);
2908         struct scsi_info *vscsi = container_of(p_timer, struct scsi_info,
2909                                                rsp_q_timer);
2910
2911         spin_lock_bh(&vscsi->intr_lock);
2912         p_timer->timer_pops += 1;
2913         p_timer->started = false;
2914         ibmvscsis_send_messages(vscsi);
2915         spin_unlock_bh(&vscsi->intr_lock);
2916
2917         return HRTIMER_NORESTART;
2918 }
2919
2920 static long ibmvscsis_alloctimer(struct scsi_info *vscsi)
2921 {
2922         struct timer_cb *p_timer;
2923
2924         p_timer = &vscsi->rsp_q_timer;
2925         hrtimer_init(&p_timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
2926
2927         p_timer->timer.function = ibmvscsis_service_wait_q;
2928         p_timer->started = false;
2929         p_timer->timer_pops = 0;
2930
2931         return ADAPT_SUCCESS;
2932 }
2933
2934 static void ibmvscsis_freetimer(struct scsi_info *vscsi)
2935 {
2936         struct timer_cb *p_timer;
2937
2938         p_timer = &vscsi->rsp_q_timer;
2939
2940         (void)hrtimer_cancel(&p_timer->timer);
2941
2942         p_timer->started = false;
2943         p_timer->timer_pops = 0;
2944 }
2945
2946 static irqreturn_t ibmvscsis_interrupt(int dummy, void *data)
2947 {
2948         struct scsi_info *vscsi = data;
2949
2950         vio_disable_interrupts(vscsi->dma_dev);
2951         tasklet_schedule(&vscsi->work_task);
2952
2953         return IRQ_HANDLED;
2954 }
2955
2956 /**
2957  * ibmvscsis_enable_change_state() - Set new state based on enabled status
2958  * @vscsi:      Pointer to our adapter structure
2959  *
2960  * This function determines our new state now that we are enabled.  This
2961  * may involve sending an Init Complete message to the client.
2962  *
2963  * Must be called with interrupt lock held.
2964  */
2965 static long ibmvscsis_enable_change_state(struct scsi_info *vscsi)
2966 {
2967         int bytes;
2968         long rc = ADAPT_SUCCESS;
2969
2970         bytes = vscsi->cmd_q.size * PAGE_SIZE;
2971         rc = h_reg_crq(vscsi->dds.unit_id, vscsi->cmd_q.crq_token, bytes);
2972         if (rc == H_CLOSED || rc == H_SUCCESS) {
2973                 vscsi->state = WAIT_CONNECTION;
2974                 rc = ibmvscsis_establish_new_q(vscsi);
2975         }
2976
2977         if (rc != ADAPT_SUCCESS) {
2978                 vscsi->state = ERR_DISCONNECTED;
2979                 vscsi->flags |= RESPONSE_Q_DOWN;
2980         }
2981
2982         return rc;
2983 }
2984
2985 /**
2986  * ibmvscsis_create_command_q() - Create Command Queue
2987  * @vscsi:      Pointer to our adapter structure
2988  * @num_cmds:   Currently unused.  In the future, may be used to determine
2989  *              the size of the CRQ.
2990  *
2991  * Allocates memory for command queue maps remote memory into an ioba
2992  * initializes the command response queue
2993  *
2994  * EXECUTION ENVIRONMENT:
2995  *      Process level only
2996  */
2997 static long ibmvscsis_create_command_q(struct scsi_info *vscsi, int num_cmds)
2998 {
2999         int pages;
3000         struct vio_dev *vdev = vscsi->dma_dev;
3001
3002         /* We might support multiple pages in the future, but just 1 for now */
3003         pages = 1;
3004
3005         vscsi->cmd_q.size = pages;
3006
3007         vscsi->cmd_q.base_addr =
3008                 (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
3009         if (!vscsi->cmd_q.base_addr)
3010                 return -ENOMEM;
3011
3012         vscsi->cmd_q.mask = ((uint)pages * CRQ_PER_PAGE) - 1;
3013
3014         vscsi->cmd_q.crq_token = dma_map_single(&vdev->dev,
3015                                                 vscsi->cmd_q.base_addr,
3016                                                 PAGE_SIZE, DMA_BIDIRECTIONAL);
3017         if (dma_mapping_error(&vdev->dev, vscsi->cmd_q.crq_token)) {
3018                 free_page((unsigned long)vscsi->cmd_q.base_addr);
3019                 return -ENOMEM;
3020         }
3021
3022         return 0;
3023 }
3024
3025 /**
3026  * ibmvscsis_destroy_command_q - Destroy Command Queue
3027  * @vscsi:      Pointer to our adapter structure
3028  *
3029  * Releases memory for command queue and unmaps mapped remote memory.
3030  *
3031  * EXECUTION ENVIRONMENT:
3032  *      Process level only
3033  */
3034 static void ibmvscsis_destroy_command_q(struct scsi_info *vscsi)
3035 {
3036         dma_unmap_single(&vscsi->dma_dev->dev, vscsi->cmd_q.crq_token,
3037                          PAGE_SIZE, DMA_BIDIRECTIONAL);
3038         free_page((unsigned long)vscsi->cmd_q.base_addr);
3039         vscsi->cmd_q.base_addr = NULL;
3040         vscsi->state = NO_QUEUE;
3041 }
3042
3043 static u8 ibmvscsis_fast_fail(struct scsi_info *vscsi,
3044                               struct ibmvscsis_cmd *cmd)
3045 {
3046         struct iu_entry *iue = cmd->iue;
3047         struct se_cmd *se_cmd = &cmd->se_cmd;
3048         struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
3049         struct scsi_sense_hdr sshdr;
3050         u8 rc = se_cmd->scsi_status;
3051
3052         if (vscsi->fast_fail && (READ_CMD(srp->cdb) || WRITE_CMD(srp->cdb)))
3053                 if (scsi_normalize_sense(se_cmd->sense_buffer,
3054                                          se_cmd->scsi_sense_length, &sshdr))
3055                         if (sshdr.sense_key == HARDWARE_ERROR &&
3056                             (se_cmd->residual_count == 0 ||
3057                              se_cmd->residual_count == se_cmd->data_length)) {
3058                                 rc = NO_SENSE;
3059                                 cmd->flags |= CMD_FAST_FAIL;
3060                         }
3061
3062         return rc;
3063 }
3064
3065 /**
3066  * srp_build_response() - Build an SRP response buffer
3067  * @vscsi:      Pointer to our adapter structure
3068  * @cmd:        Pointer to command for which to send the response
3069  * @len_p:      Where to return the length of the IU response sent.  This
3070  *              is needed to construct the CRQ response.
3071  *
3072  * Build the SRP response buffer and copy it to the client's memory space.
3073  */
3074 static long srp_build_response(struct scsi_info *vscsi,
3075                                struct ibmvscsis_cmd *cmd, uint *len_p)
3076 {
3077         struct iu_entry *iue = cmd->iue;
3078         struct se_cmd *se_cmd = &cmd->se_cmd;
3079         struct srp_rsp *rsp;
3080         uint len;
3081         u32 rsp_code;
3082         char *data;
3083         u32 *tsk_status;
3084         long rc = ADAPT_SUCCESS;
3085
3086         spin_lock_bh(&vscsi->intr_lock);
3087
3088         rsp = &vio_iu(iue)->srp.rsp;
3089         len = sizeof(*rsp);
3090         memset(rsp, 0, len);
3091         data = rsp->data;
3092
3093         rsp->opcode = SRP_RSP;
3094
3095         rsp->req_lim_delta = cpu_to_be32(1 + vscsi->credit);
3096         rsp->tag = cmd->rsp.tag;
3097         rsp->flags = 0;
3098
3099         if (cmd->type == SCSI_CDB) {
3100                 rsp->status = ibmvscsis_fast_fail(vscsi, cmd);
3101                 if (rsp->status) {
3102                         dev_dbg(&vscsi->dev, "build_resp: cmd %p, scsi status %d\n",
3103                                 cmd, (int)rsp->status);
3104                         ibmvscsis_determine_resid(se_cmd, rsp);
3105                         if (se_cmd->scsi_sense_length && se_cmd->sense_buffer) {
3106                                 rsp->sense_data_len =
3107                                         cpu_to_be32(se_cmd->scsi_sense_length);
3108                                 rsp->flags |= SRP_RSP_FLAG_SNSVALID;
3109                                 len += se_cmd->scsi_sense_length;
3110                                 memcpy(data, se_cmd->sense_buffer,
3111                                        se_cmd->scsi_sense_length);
3112                         }
3113                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
3114                                 UCSOLNT_RESP_SHIFT;
3115                 } else if (cmd->flags & CMD_FAST_FAIL) {
3116                         dev_dbg(&vscsi->dev, "build_resp: cmd %p, fast fail\n",
3117                                 cmd);
3118                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
3119                                 UCSOLNT_RESP_SHIFT;
3120                 } else {
3121                         rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
3122                                 SCSOLNT_RESP_SHIFT;
3123                 }
3124         } else {
3125                 /* this is task management */
3126                 rsp->status = 0;
3127                 rsp->resp_data_len = cpu_to_be32(4);
3128                 rsp->flags |= SRP_RSP_FLAG_RSPVALID;
3129
3130                 switch (se_cmd->se_tmr_req->response) {
3131                 case TMR_FUNCTION_COMPLETE:
3132                 case TMR_TASK_DOES_NOT_EXIST:
3133                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_COMPLETE;
3134                         rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
3135                                 SCSOLNT_RESP_SHIFT;
3136                         break;
3137                 case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3138                 case TMR_LUN_DOES_NOT_EXIST:
3139                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_NOT_SUPPORTED;
3140                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
3141                                 UCSOLNT_RESP_SHIFT;
3142                         break;
3143                 case TMR_FUNCTION_FAILED:
3144                 case TMR_FUNCTION_REJECTED:
3145                 default:
3146                         rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_FAILED;
3147                         rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
3148                                 UCSOLNT_RESP_SHIFT;
3149                         break;
3150                 }
3151
3152                 tsk_status = (u32 *)data;
3153                 *tsk_status = cpu_to_be32(rsp_code);
3154                 data = (char *)(tsk_status + 1);
3155                 len += 4;
3156         }
3157
3158         dma_wmb();
3159         rc = h_copy_rdma(len, vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
3160                          vscsi->dds.window[REMOTE].liobn,
3161                          be64_to_cpu(iue->remote_token));
3162
3163         switch (rc) {
3164         case H_SUCCESS:
3165                 vscsi->credit = 0;
3166                 *len_p = len;
3167                 break;
3168         case H_PERMISSION:
3169                 if (connection_broken(vscsi))
3170                         vscsi->flags |= RESPONSE_Q_DOWN | CLIENT_FAILED;
3171
3172                 dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld, flags 0x%x, state 0x%hx\n",
3173                         rc, vscsi->flags, vscsi->state);
3174                 break;
3175         case H_SOURCE_PARM:
3176         case H_DEST_PARM:
3177         default:
3178                 dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld\n",
3179                         rc);
3180                 break;
3181         }
3182
3183         spin_unlock_bh(&vscsi->intr_lock);
3184
3185         return rc;
3186 }
3187
3188 static int ibmvscsis_rdma(struct ibmvscsis_cmd *cmd, struct scatterlist *sg,
3189                           int nsg, struct srp_direct_buf *md, int nmd,
3190                           enum dma_data_direction dir, unsigned int bytes)
3191 {
3192         struct iu_entry *iue = cmd->iue;
3193         struct srp_target *target = iue->target;
3194         struct scsi_info *vscsi = target->ldata;
3195         struct scatterlist *sgp;
3196         dma_addr_t client_ioba, server_ioba;
3197         ulong buf_len;
3198         ulong client_len, server_len;
3199         int md_idx;
3200         long tx_len;
3201         long rc = 0;
3202
3203         if (bytes == 0)
3204                 return 0;
3205
3206         sgp = sg;
3207         client_len = 0;
3208         server_len = 0;
3209         md_idx = 0;
3210         tx_len = bytes;
3211
3212         do {
3213                 if (client_len == 0) {
3214                         if (md_idx >= nmd) {
3215                                 dev_err(&vscsi->dev, "rdma: ran out of client memory descriptors\n");
3216                                 rc = -EIO;
3217                                 break;
3218                         }
3219                         client_ioba = be64_to_cpu(md[md_idx].va);
3220                         client_len = be32_to_cpu(md[md_idx].len);
3221                 }
3222                 if (server_len == 0) {
3223                         if (!sgp) {
3224                                 dev_err(&vscsi->dev, "rdma: ran out of scatter/gather list\n");
3225                                 rc = -EIO;
3226                                 break;
3227                         }
3228                         server_ioba = sg_dma_address(sgp);
3229                         server_len = sg_dma_len(sgp);
3230                 }
3231
3232                 buf_len = tx_len;
3233
3234                 if (buf_len > client_len)
3235                         buf_len = client_len;
3236
3237                 if (buf_len > server_len)
3238                         buf_len = server_len;
3239
3240                 if (buf_len > max_vdma_size)
3241                         buf_len = max_vdma_size;
3242
3243                 if (dir == DMA_TO_DEVICE) {
3244                         /* read from client */
3245                         rc = h_copy_rdma(buf_len,
3246                                          vscsi->dds.window[REMOTE].liobn,
3247                                          client_ioba,
3248                                          vscsi->dds.window[LOCAL].liobn,
3249                                          server_ioba);
3250                 } else {
3251                         /* The h_copy_rdma will cause phyp, running in another
3252                          * partition, to read memory, so we need to make sure
3253                          * the data has been written out, hence these syncs.
3254                          */
3255                         /* ensure that everything is in memory */
3256                         isync();
3257                         /* ensure that memory has been made visible */
3258                         dma_wmb();
3259                         rc = h_copy_rdma(buf_len,
3260                                          vscsi->dds.window[LOCAL].liobn,
3261                                          server_ioba,
3262                                          vscsi->dds.window[REMOTE].liobn,
3263                                          client_ioba);
3264                 }
3265                 switch (rc) {
3266                 case H_SUCCESS:
3267                         break;
3268                 case H_PERMISSION:
3269                 case H_SOURCE_PARM:
3270                 case H_DEST_PARM:
3271                         if (connection_broken(vscsi)) {
3272                                 spin_lock_bh(&vscsi->intr_lock);
3273                                 vscsi->flags |=
3274                                         (RESPONSE_Q_DOWN | CLIENT_FAILED);
3275                                 spin_unlock_bh(&vscsi->intr_lock);
3276                         }
3277                         dev_err(&vscsi->dev, "rdma: h_copy_rdma failed, rc %ld\n",
3278                                 rc);
3279                         break;
3280
3281                 default:
3282                         dev_err(&vscsi->dev, "rdma: unknown error %ld from h_copy_rdma\n",
3283                                 rc);
3284                         break;
3285                 }
3286
3287                 if (!rc) {
3288                         tx_len -= buf_len;
3289                         if (tx_len) {
3290                                 client_len -= buf_len;
3291                                 if (client_len == 0)
3292                                         md_idx++;
3293                                 else
3294                                         client_ioba += buf_len;
3295
3296                                 server_len -= buf_len;
3297                                 if (server_len == 0)
3298                                         sgp = sg_next(sgp);
3299                                 else
3300                                         server_ioba += buf_len;
3301                         } else {
3302                                 break;
3303                         }
3304                 }
3305         } while (!rc);
3306
3307         return rc;
3308 }
3309
3310 /**
3311  * ibmvscsis_handle_crq() - Handle CRQ
3312  * @data:       Pointer to our adapter structure
3313  *
3314  * Read the command elements from the command queue and copy the payloads
3315  * associated with the command elements to local memory and execute the
3316  * SRP requests.
3317  *
3318  * Note: this is an edge triggered interrupt. It can not be shared.
3319  */
3320 static void ibmvscsis_handle_crq(unsigned long data)
3321 {
3322         struct scsi_info *vscsi = (struct scsi_info *)data;
3323         struct viosrp_crq *crq;
3324         long rc;
3325         bool ack = true;
3326         volatile u8 valid;
3327
3328         spin_lock_bh(&vscsi->intr_lock);
3329
3330         dev_dbg(&vscsi->dev, "got interrupt\n");
3331
3332         /*
3333          * if we are in a path where we are waiting for all pending commands
3334          * to complete because we received a transport event and anything in
3335          * the command queue is for a new connection, do nothing
3336          */
3337         if (TARGET_STOP(vscsi)) {
3338                 vio_enable_interrupts(vscsi->dma_dev);
3339
3340                 dev_dbg(&vscsi->dev, "handle_crq, don't process: flags 0x%x, state 0x%hx\n",
3341                         vscsi->flags, vscsi->state);
3342                 spin_unlock_bh(&vscsi->intr_lock);
3343                 return;
3344         }
3345
3346         rc = vscsi->flags & SCHEDULE_DISCONNECT;
3347         crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
3348         valid = crq->valid;
3349         dma_rmb();
3350
3351         while (valid) {
3352                 /*
3353                  * These are edege triggered interrupts. After dropping out of
3354                  * the while loop, the code must check for work since an
3355                  * interrupt could be lost, and an elment be left on the queue,
3356                  * hence the label.
3357                  */
3358 cmd_work:
3359                 vscsi->cmd_q.index =
3360                         (vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
3361
3362                 if (!rc) {
3363                         rc = ibmvscsis_parse_command(vscsi, crq);
3364                 } else {
3365                         if ((uint)crq->valid == VALID_TRANS_EVENT) {
3366                                 /*
3367                                  * must service the transport layer events even
3368                                  * in an error state, dont break out until all
3369                                  * the consecutive transport events have been
3370                                  * processed
3371                                  */
3372                                 rc = ibmvscsis_trans_event(vscsi, crq);
3373                         } else if (vscsi->flags & TRANS_EVENT) {
3374                                 /*
3375                                  * if a transport event has occurred leave
3376                                  * everything but transport events on the queue
3377                                  *
3378                                  * need to decrement the queue index so we can
3379                                  * look at the element again
3380                                  */
3381                                 if (vscsi->cmd_q.index)
3382                                         vscsi->cmd_q.index -= 1;
3383                                 else
3384                                         /*
3385                                          * index is at 0 it just wrapped.
3386                                          * have it index last element in q
3387                                          */
3388                                         vscsi->cmd_q.index = vscsi->cmd_q.mask;
3389                                 break;
3390                         }
3391                 }
3392
3393                 crq->valid = INVALIDATE_CMD_RESP_EL;
3394
3395                 crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
3396                 valid = crq->valid;
3397                 dma_rmb();
3398         }
3399
3400         if (!rc) {
3401                 if (ack) {
3402                         vio_enable_interrupts(vscsi->dma_dev);
3403                         ack = false;
3404                         dev_dbg(&vscsi->dev, "handle_crq, reenabling interrupts\n");
3405                 }
3406                 valid = crq->valid;
3407                 dma_rmb();
3408                 if (valid)
3409                         goto cmd_work;
3410         } else {
3411                 dev_dbg(&vscsi->dev, "handle_crq, error: flags 0x%x, state 0x%hx, crq index 0x%x\n",
3412                         vscsi->flags, vscsi->state, vscsi->cmd_q.index);
3413         }
3414
3415         dev_dbg(&vscsi->dev, "Leaving handle_crq: schedule_q empty %d, flags 0x%x, state 0x%hx\n",
3416                 (int)list_empty(&vscsi->schedule_q), vscsi->flags,
3417                 vscsi->state);
3418
3419         spin_unlock_bh(&vscsi->intr_lock);
3420 }
3421
3422 static int ibmvscsis_probe(struct vio_dev *vdev,
3423                            const struct vio_device_id *id)
3424 {
3425         struct scsi_info *vscsi;
3426         int rc = 0;
3427         long hrc = 0;
3428         char wq_name[24];
3429
3430         vscsi = kzalloc(sizeof(*vscsi), GFP_KERNEL);
3431         if (!vscsi) {
3432                 rc = -ENOMEM;
3433                 dev_err(&vdev->dev, "probe: allocation of adapter failed\n");
3434                 return rc;
3435         }
3436
3437         vscsi->dma_dev = vdev;
3438         vscsi->dev = vdev->dev;
3439         INIT_LIST_HEAD(&vscsi->schedule_q);
3440         INIT_LIST_HEAD(&vscsi->waiting_rsp);
3441         INIT_LIST_HEAD(&vscsi->active_q);
3442
3443         snprintf(vscsi->tport.tport_name, IBMVSCSIS_NAMELEN, "%s",
3444                  dev_name(&vdev->dev));
3445
3446         dev_dbg(&vscsi->dev, "probe tport_name: %s\n", vscsi->tport.tport_name);
3447
3448         rc = read_dma_window(vscsi);
3449         if (rc)
3450                 goto free_adapter;
3451         dev_dbg(&vscsi->dev, "Probe: liobn 0x%x, riobn 0x%x\n",
3452                 vscsi->dds.window[LOCAL].liobn,
3453                 vscsi->dds.window[REMOTE].liobn);
3454
3455         snprintf(vscsi->eye, sizeof(vscsi->eye), "VSCSI %s", vdev->name);
3456
3457         vscsi->dds.unit_id = vdev->unit_address;
3458         strscpy(vscsi->dds.partition_name, partition_name,
3459                 sizeof(vscsi->dds.partition_name));
3460         vscsi->dds.partition_num = partition_number;
3461
3462         spin_lock_bh(&ibmvscsis_dev_lock);
3463         list_add_tail(&vscsi->list, &ibmvscsis_dev_list);
3464         spin_unlock_bh(&ibmvscsis_dev_lock);
3465
3466         /*
3467          * TBD: How do we determine # of cmds to request?  Do we know how
3468          * many "children" we have?
3469          */
3470         vscsi->request_limit = INITIAL_SRP_LIMIT;
3471         rc = srp_target_alloc(&vscsi->target, &vdev->dev, vscsi->request_limit,
3472                               SRP_MAX_IU_LEN);
3473         if (rc)
3474                 goto rem_list;
3475
3476         vscsi->target.ldata = vscsi;
3477
3478         rc = ibmvscsis_alloc_cmds(vscsi, vscsi->request_limit);
3479         if (rc) {
3480                 dev_err(&vscsi->dev, "alloc_cmds failed, rc %d, num %d\n",
3481                         rc, vscsi->request_limit);
3482                 goto free_target;
3483         }
3484
3485         /*
3486          * Note: the lock is used in freeing timers, so must initialize
3487          * first so that ordering in case of error is correct.
3488          */
3489         spin_lock_init(&vscsi->intr_lock);
3490
3491         rc = ibmvscsis_alloctimer(vscsi);
3492         if (rc) {
3493                 dev_err(&vscsi->dev, "probe: alloctimer failed, rc %d\n", rc);
3494                 goto free_cmds;
3495         }
3496
3497         rc = ibmvscsis_create_command_q(vscsi, 256);
3498         if (rc) {
3499                 dev_err(&vscsi->dev, "probe: create_command_q failed, rc %d\n",
3500                         rc);
3501                 goto free_timer;
3502         }
3503
3504         vscsi->map_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
3505         if (!vscsi->map_buf) {
3506                 rc = -ENOMEM;
3507                 dev_err(&vscsi->dev, "probe: allocating cmd buffer failed\n");
3508                 goto destroy_queue;
3509         }
3510
3511         vscsi->map_ioba = dma_map_single(&vdev->dev, vscsi->map_buf, PAGE_SIZE,
3512                                          DMA_BIDIRECTIONAL);
3513         if (dma_mapping_error(&vdev->dev, vscsi->map_ioba)) {
3514                 rc = -ENOMEM;
3515                 dev_err(&vscsi->dev, "probe: error mapping command buffer\n");
3516                 goto free_buf;
3517         }
3518
3519         hrc = h_vioctl(vscsi->dds.unit_id, H_GET_PARTNER_INFO,
3520                        (u64)vscsi->map_ioba | ((u64)PAGE_SIZE << 32), 0, 0, 0,
3521                        0);
3522         if (hrc == H_SUCCESS)
3523                 vscsi->client_data.partition_number =
3524                         be64_to_cpu(*(u64 *)vscsi->map_buf);
3525         /*
3526          * We expect the VIOCTL to fail if we're configured as "any
3527          * client can connect" and the client isn't activated yet.
3528          * We'll make the call again when he sends an init msg.
3529          */
3530         dev_dbg(&vscsi->dev, "probe hrc %ld, client partition num %d\n",
3531                 hrc, vscsi->client_data.partition_number);
3532
3533         tasklet_init(&vscsi->work_task, ibmvscsis_handle_crq,
3534                      (unsigned long)vscsi);
3535
3536         init_completion(&vscsi->wait_idle);
3537         init_completion(&vscsi->unconfig);
3538
3539         snprintf(wq_name, 24, "ibmvscsis%s", dev_name(&vdev->dev));
3540         vscsi->work_q = create_workqueue(wq_name);
3541         if (!vscsi->work_q) {
3542                 rc = -ENOMEM;
3543                 dev_err(&vscsi->dev, "create_workqueue failed\n");
3544                 goto unmap_buf;
3545         }
3546
3547         rc = request_irq(vdev->irq, ibmvscsis_interrupt, 0, "ibmvscsis", vscsi);
3548         if (rc) {
3549                 rc = -EPERM;
3550                 dev_err(&vscsi->dev, "probe: request_irq failed, rc %d\n", rc);
3551                 goto destroy_WQ;
3552         }
3553
3554         vscsi->state = WAIT_ENABLED;
3555
3556         dev_set_drvdata(&vdev->dev, vscsi);
3557
3558         return 0;
3559
3560 destroy_WQ:
3561         destroy_workqueue(vscsi->work_q);
3562 unmap_buf:
3563         dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
3564                          DMA_BIDIRECTIONAL);
3565 free_buf:
3566         kfree(vscsi->map_buf);
3567 destroy_queue:
3568         tasklet_kill(&vscsi->work_task);
3569         ibmvscsis_unregister_command_q(vscsi);
3570         ibmvscsis_destroy_command_q(vscsi);
3571 free_timer:
3572         ibmvscsis_freetimer(vscsi);
3573 free_cmds:
3574         ibmvscsis_free_cmds(vscsi);
3575 free_target:
3576         srp_target_free(&vscsi->target);
3577 rem_list:
3578         spin_lock_bh(&ibmvscsis_dev_lock);
3579         list_del(&vscsi->list);
3580         spin_unlock_bh(&ibmvscsis_dev_lock);
3581 free_adapter:
3582         kfree(vscsi);
3583
3584         return rc;
3585 }
3586
3587 static void ibmvscsis_remove(struct vio_dev *vdev)
3588 {
3589         struct scsi_info *vscsi = dev_get_drvdata(&vdev->dev);
3590
3591         dev_dbg(&vscsi->dev, "remove (%s)\n", dev_name(&vscsi->dma_dev->dev));
3592
3593         spin_lock_bh(&vscsi->intr_lock);
3594         ibmvscsis_post_disconnect(vscsi, UNCONFIGURING, 0);
3595         vscsi->flags |= CFG_SLEEPING;
3596         spin_unlock_bh(&vscsi->intr_lock);
3597         wait_for_completion(&vscsi->unconfig);
3598
3599         vio_disable_interrupts(vdev);
3600         free_irq(vdev->irq, vscsi);
3601         destroy_workqueue(vscsi->work_q);
3602         dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
3603                          DMA_BIDIRECTIONAL);
3604         kfree(vscsi->map_buf);
3605         tasklet_kill(&vscsi->work_task);
3606         ibmvscsis_destroy_command_q(vscsi);
3607         ibmvscsis_freetimer(vscsi);
3608         ibmvscsis_free_cmds(vscsi);
3609         srp_target_free(&vscsi->target);
3610         spin_lock_bh(&ibmvscsis_dev_lock);
3611         list_del(&vscsi->list);
3612         spin_unlock_bh(&ibmvscsis_dev_lock);
3613         kfree(vscsi);
3614 }
3615
3616 static ssize_t system_id_show(struct device *dev,
3617                               struct device_attribute *attr, char *buf)
3618 {
3619         return snprintf(buf, PAGE_SIZE, "%s\n", system_id);
3620 }
3621
3622 static ssize_t partition_number_show(struct device *dev,
3623                                      struct device_attribute *attr, char *buf)
3624 {
3625         return snprintf(buf, PAGE_SIZE, "%x\n", partition_number);
3626 }
3627
3628 static ssize_t unit_address_show(struct device *dev,
3629                                  struct device_attribute *attr, char *buf)
3630 {
3631         struct scsi_info *vscsi = container_of(dev, struct scsi_info, dev);
3632
3633         return snprintf(buf, PAGE_SIZE, "%x\n", vscsi->dma_dev->unit_address);
3634 }
3635
3636 static int ibmvscsis_get_system_info(void)
3637 {
3638         struct device_node *rootdn, *vdevdn;
3639         const char *id, *model, *name;
3640         const uint *num;
3641
3642         rootdn = of_find_node_by_path("/");
3643         if (!rootdn)
3644                 return -ENOENT;
3645
3646         model = of_get_property(rootdn, "model", NULL);
3647         id = of_get_property(rootdn, "system-id", NULL);
3648         if (model && id)
3649                 snprintf(system_id, sizeof(system_id), "%s-%s", model, id);
3650
3651         name = of_get_property(rootdn, "ibm,partition-name", NULL);
3652         if (name)
3653                 strncpy(partition_name, name, sizeof(partition_name));
3654
3655         num = of_get_property(rootdn, "ibm,partition-no", NULL);
3656         if (num)
3657                 partition_number = of_read_number(num, 1);
3658
3659         of_node_put(rootdn);
3660
3661         vdevdn = of_find_node_by_path("/vdevice");
3662         if (vdevdn) {
3663                 const uint *mvds;
3664
3665                 mvds = of_get_property(vdevdn, "ibm,max-virtual-dma-size",
3666                                        NULL);
3667                 if (mvds)
3668                         max_vdma_size = *mvds;
3669                 of_node_put(vdevdn);
3670         }
3671
3672         return 0;
3673 }
3674
3675 static char *ibmvscsis_get_fabric_wwn(struct se_portal_group *se_tpg)
3676 {
3677         struct ibmvscsis_tport *tport =
3678                 container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
3679
3680         return tport->tport_name;
3681 }
3682
3683 static u16 ibmvscsis_get_tag(struct se_portal_group *se_tpg)
3684 {
3685         struct ibmvscsis_tport *tport =
3686                 container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
3687
3688         return tport->tport_tpgt;
3689 }
3690
3691 static u32 ibmvscsis_get_default_depth(struct se_portal_group *se_tpg)
3692 {
3693         return 1;
3694 }
3695
3696 static int ibmvscsis_check_true(struct se_portal_group *se_tpg)
3697 {
3698         return 1;
3699 }
3700
3701 static int ibmvscsis_check_false(struct se_portal_group *se_tpg)
3702 {
3703         return 0;
3704 }
3705
3706 static u32 ibmvscsis_tpg_get_inst_index(struct se_portal_group *se_tpg)
3707 {
3708         return 1;
3709 }
3710
3711 static int ibmvscsis_check_stop_free(struct se_cmd *se_cmd)
3712 {
3713         return target_put_sess_cmd(se_cmd);
3714 }
3715
3716 static void ibmvscsis_release_cmd(struct se_cmd *se_cmd)
3717 {
3718         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3719                                                  se_cmd);
3720         struct scsi_info *vscsi = cmd->adapter;
3721
3722         spin_lock_bh(&vscsi->intr_lock);
3723         /* Remove from active_q */
3724         list_move_tail(&cmd->list, &vscsi->waiting_rsp);
3725         ibmvscsis_send_messages(vscsi);
3726         spin_unlock_bh(&vscsi->intr_lock);
3727 }
3728
3729 static u32 ibmvscsis_sess_get_index(struct se_session *se_sess)
3730 {
3731         return 0;
3732 }
3733
3734 static int ibmvscsis_write_pending(struct se_cmd *se_cmd)
3735 {
3736         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3737                                                  se_cmd);
3738         struct scsi_info *vscsi = cmd->adapter;
3739         struct iu_entry *iue = cmd->iue;
3740         int rc;
3741
3742         /*
3743          * If CLIENT_FAILED OR RESPONSE_Q_DOWN, then just return success
3744          * since LIO can't do anything about it, and we dont want to
3745          * attempt an srp_transfer_data.
3746          */
3747         if ((vscsi->flags & (CLIENT_FAILED | RESPONSE_Q_DOWN))) {
3748                 dev_err(&vscsi->dev, "write_pending failed since: %d\n",
3749                         vscsi->flags);
3750                 return -EIO;
3751
3752         }
3753
3754         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma,
3755                                1, 1);
3756         if (rc) {
3757                 dev_err(&vscsi->dev, "srp_transfer_data() failed: %d\n", rc);
3758                 return -EIO;
3759         }
3760         /*
3761          * We now tell TCM to add this WRITE CDB directly into the TCM storage
3762          * object execution queue.
3763          */
3764         target_execute_cmd(se_cmd);
3765         return 0;
3766 }
3767
3768 static void ibmvscsis_set_default_node_attrs(struct se_node_acl *nacl)
3769 {
3770 }
3771
3772 static int ibmvscsis_get_cmd_state(struct se_cmd *se_cmd)
3773 {
3774         return 0;
3775 }
3776
3777 static int ibmvscsis_queue_data_in(struct se_cmd *se_cmd)
3778 {
3779         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3780                                                  se_cmd);
3781         struct iu_entry *iue = cmd->iue;
3782         struct scsi_info *vscsi = cmd->adapter;
3783         uint len = 0;
3784         int rc;
3785
3786         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma, 1,
3787                                1);
3788         if (rc) {
3789                 dev_err(&vscsi->dev, "srp_transfer_data failed: %d\n", rc);
3790                 se_cmd->scsi_sense_length = 18;
3791                 memset(se_cmd->sense_buffer, 0, se_cmd->scsi_sense_length);
3792                 /* Logical Unit Communication Time-out asc/ascq = 0x0801 */
3793                 scsi_build_sense_buffer(0, se_cmd->sense_buffer, MEDIUM_ERROR,
3794                                         0x08, 0x01);
3795         }
3796
3797         srp_build_response(vscsi, cmd, &len);
3798         cmd->rsp.format = SRP_FORMAT;
3799         cmd->rsp.len = len;
3800
3801         return 0;
3802 }
3803
3804 static int ibmvscsis_queue_status(struct se_cmd *se_cmd)
3805 {
3806         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3807                                                  se_cmd);
3808         struct scsi_info *vscsi = cmd->adapter;
3809         uint len;
3810
3811         dev_dbg(&vscsi->dev, "queue_status %p\n", se_cmd);
3812
3813         srp_build_response(vscsi, cmd, &len);
3814         cmd->rsp.format = SRP_FORMAT;
3815         cmd->rsp.len = len;
3816
3817         return 0;
3818 }
3819
3820 static void ibmvscsis_queue_tm_rsp(struct se_cmd *se_cmd)
3821 {
3822         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3823                                                  se_cmd);
3824         struct scsi_info *vscsi = cmd->adapter;
3825         struct ibmvscsis_cmd *cmd_itr;
3826         struct iu_entry *iue = iue = cmd->iue;
3827         struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
3828         u64 tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
3829         uint len;
3830
3831         dev_dbg(&vscsi->dev, "queue_tm_rsp %p, status %d\n",
3832                 se_cmd, (int)se_cmd->se_tmr_req->response);
3833
3834         if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK &&
3835             cmd->se_cmd.se_tmr_req->response == TMR_TASK_DOES_NOT_EXIST) {
3836                 spin_lock_bh(&vscsi->intr_lock);
3837                 list_for_each_entry(cmd_itr, &vscsi->active_q, list) {
3838                         if (tag_to_abort == cmd_itr->se_cmd.tag) {
3839                                 cmd_itr->abort_cmd = cmd;
3840                                 cmd->flags |= DELAY_SEND;
3841                                 break;
3842                         }
3843                 }
3844                 spin_unlock_bh(&vscsi->intr_lock);
3845         }
3846
3847         srp_build_response(vscsi, cmd, &len);
3848         cmd->rsp.format = SRP_FORMAT;
3849         cmd->rsp.len = len;
3850 }
3851
3852 static void ibmvscsis_aborted_task(struct se_cmd *se_cmd)
3853 {
3854         struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
3855                                                  se_cmd);
3856         struct scsi_info *vscsi = cmd->adapter;
3857
3858         dev_dbg(&vscsi->dev, "ibmvscsis_aborted_task %p task_tag: %llu\n",
3859                 se_cmd, se_cmd->tag);
3860 }
3861
3862 static struct se_wwn *ibmvscsis_make_tport(struct target_fabric_configfs *tf,
3863                                            struct config_group *group,
3864                                            const char *name)
3865 {
3866         struct ibmvscsis_tport *tport;
3867         struct scsi_info *vscsi;
3868
3869         tport = ibmvscsis_lookup_port(name);
3870         if (tport) {
3871                 vscsi = container_of(tport, struct scsi_info, tport);
3872                 tport->tport_proto_id = SCSI_PROTOCOL_SRP;
3873                 dev_dbg(&vscsi->dev, "make_tport(%s), pointer:%p, tport_id:%x\n",
3874                         name, tport, tport->tport_proto_id);
3875                 return &tport->tport_wwn;
3876         }
3877
3878         return ERR_PTR(-EINVAL);
3879 }
3880
3881 static void ibmvscsis_drop_tport(struct se_wwn *wwn)
3882 {
3883         struct ibmvscsis_tport *tport = container_of(wwn,
3884                                                      struct ibmvscsis_tport,
3885                                                      tport_wwn);
3886         struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
3887
3888         dev_dbg(&vscsi->dev, "drop_tport(%s)\n",
3889                 config_item_name(&tport->tport_wwn.wwn_group.cg_item));
3890 }
3891
3892 static struct se_portal_group *ibmvscsis_make_tpg(struct se_wwn *wwn,
3893                                                   const char *name)
3894 {
3895         struct ibmvscsis_tport *tport =
3896                 container_of(wwn, struct ibmvscsis_tport, tport_wwn);
3897         u16 tpgt;
3898         int rc;
3899
3900         if (strstr(name, "tpgt_") != name)
3901                 return ERR_PTR(-EINVAL);
3902         rc = kstrtou16(name + 5, 0, &tpgt);
3903         if (rc)
3904                 return ERR_PTR(rc);
3905         tport->tport_tpgt = tpgt;
3906
3907         tport->releasing = false;
3908
3909         rc = core_tpg_register(&tport->tport_wwn, &tport->se_tpg,
3910                                tport->tport_proto_id);
3911         if (rc)
3912                 return ERR_PTR(rc);
3913
3914         return &tport->se_tpg;
3915 }
3916
3917 static void ibmvscsis_drop_tpg(struct se_portal_group *se_tpg)
3918 {
3919         struct ibmvscsis_tport *tport = container_of(se_tpg,
3920                                                      struct ibmvscsis_tport,
3921                                                      se_tpg);
3922
3923         tport->releasing = true;
3924         tport->enabled = false;
3925
3926         /*
3927          * Release the virtual I_T Nexus for this ibmvscsis TPG
3928          */
3929         ibmvscsis_drop_nexus(tport);
3930         /*
3931          * Deregister the se_tpg from TCM..
3932          */
3933         core_tpg_deregister(se_tpg);
3934 }
3935
3936 static ssize_t ibmvscsis_wwn_version_show(struct config_item *item,
3937                                           char *page)
3938 {
3939         return scnprintf(page, PAGE_SIZE, "%s\n", IBMVSCSIS_VERSION);
3940 }
3941 CONFIGFS_ATTR_RO(ibmvscsis_wwn_, version);
3942
3943 static struct configfs_attribute *ibmvscsis_wwn_attrs[] = {
3944         &ibmvscsis_wwn_attr_version,
3945         NULL,
3946 };
3947
3948
3949 static int ibmvscsis_enable_tpg(struct se_portal_group *se_tpg, bool enable)
3950 {
3951         struct ibmvscsis_tport *tport = container_of(se_tpg,
3952                                                      struct ibmvscsis_tport,
3953                                                      se_tpg);
3954         struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
3955         long lrc;
3956
3957         if (enable) {
3958                 spin_lock_bh(&vscsi->intr_lock);
3959                 tport->enabled = true;
3960                 lrc = ibmvscsis_enable_change_state(vscsi);
3961                 if (lrc)
3962                         dev_err(&vscsi->dev, "enable_change_state failed, rc %ld state %d\n",
3963                                 lrc, vscsi->state);
3964                 spin_unlock_bh(&vscsi->intr_lock);
3965         } else {
3966                 spin_lock_bh(&vscsi->intr_lock);
3967                 tport->enabled = false;
3968                 /* This simulates the server going down */
3969                 ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
3970                 spin_unlock_bh(&vscsi->intr_lock);
3971         }
3972
3973         return 0;
3974 }
3975
3976 static const struct target_core_fabric_ops ibmvscsis_ops = {
3977         .module                         = THIS_MODULE,
3978         .fabric_name                    = "ibmvscsis",
3979         .max_data_sg_nents              = MAX_TXU / PAGE_SIZE,
3980         .tpg_get_wwn                    = ibmvscsis_get_fabric_wwn,
3981         .tpg_get_tag                    = ibmvscsis_get_tag,
3982         .tpg_get_default_depth          = ibmvscsis_get_default_depth,
3983         .tpg_check_demo_mode            = ibmvscsis_check_true,
3984         .tpg_check_demo_mode_cache      = ibmvscsis_check_true,
3985         .tpg_check_demo_mode_write_protect = ibmvscsis_check_false,
3986         .tpg_check_prod_mode_write_protect = ibmvscsis_check_false,
3987         .tpg_get_inst_index             = ibmvscsis_tpg_get_inst_index,
3988         .check_stop_free                = ibmvscsis_check_stop_free,
3989         .release_cmd                    = ibmvscsis_release_cmd,
3990         .sess_get_index                 = ibmvscsis_sess_get_index,
3991         .write_pending                  = ibmvscsis_write_pending,
3992         .set_default_node_attributes    = ibmvscsis_set_default_node_attrs,
3993         .get_cmd_state                  = ibmvscsis_get_cmd_state,
3994         .queue_data_in                  = ibmvscsis_queue_data_in,
3995         .queue_status                   = ibmvscsis_queue_status,
3996         .queue_tm_rsp                   = ibmvscsis_queue_tm_rsp,
3997         .aborted_task                   = ibmvscsis_aborted_task,
3998         /*
3999          * Setup function pointers for logic in target_core_fabric_configfs.c
4000          */
4001         .fabric_make_wwn                = ibmvscsis_make_tport,
4002         .fabric_drop_wwn                = ibmvscsis_drop_tport,
4003         .fabric_make_tpg                = ibmvscsis_make_tpg,
4004         .fabric_enable_tpg              = ibmvscsis_enable_tpg,
4005         .fabric_drop_tpg                = ibmvscsis_drop_tpg,
4006
4007         .tfc_wwn_attrs                  = ibmvscsis_wwn_attrs,
4008 };
4009
4010 static void ibmvscsis_dev_release(struct device *dev) {};
4011
4012 static struct device_attribute dev_attr_system_id =
4013         __ATTR(system_id, S_IRUGO, system_id_show, NULL);
4014
4015 static struct device_attribute dev_attr_partition_number =
4016         __ATTR(partition_number, S_IRUGO, partition_number_show, NULL);
4017
4018 static struct device_attribute dev_attr_unit_address =
4019         __ATTR(unit_address, S_IRUGO, unit_address_show, NULL);
4020
4021 static struct attribute *ibmvscsis_dev_attrs[] = {
4022         &dev_attr_system_id.attr,
4023         &dev_attr_partition_number.attr,
4024         &dev_attr_unit_address.attr,
4025 };
4026 ATTRIBUTE_GROUPS(ibmvscsis_dev);
4027
4028 static struct class ibmvscsis_class = {
4029         .name           = "ibmvscsis",
4030         .dev_release    = ibmvscsis_dev_release,
4031         .dev_groups     = ibmvscsis_dev_groups,
4032 };
4033
4034 static const struct vio_device_id ibmvscsis_device_table[] = {
4035         { "v-scsi-host", "IBM,v-scsi-host" },
4036         { "", "" }
4037 };
4038 MODULE_DEVICE_TABLE(vio, ibmvscsis_device_table);
4039
4040 static struct vio_driver ibmvscsis_driver = {
4041         .name = "ibmvscsis",
4042         .id_table = ibmvscsis_device_table,
4043         .probe = ibmvscsis_probe,
4044         .remove = ibmvscsis_remove,
4045 };
4046
4047 /*
4048  * ibmvscsis_init() - Kernel Module initialization
4049  *
4050  * Note: vio_register_driver() registers callback functions, and at least one
4051  * of those callback functions calls TCM - Linux IO Target Subsystem, thus
4052  * the SCSI Target template must be registered before vio_register_driver()
4053  * is called.
4054  */
4055 static int __init ibmvscsis_init(void)
4056 {
4057         int rc = 0;
4058
4059         rc = ibmvscsis_get_system_info();
4060         if (rc) {
4061                 pr_err("rc %d from get_system_info\n", rc);
4062                 goto out;
4063         }
4064
4065         rc = class_register(&ibmvscsis_class);
4066         if (rc) {
4067                 pr_err("failed class register\n");
4068                 goto out;
4069         }
4070
4071         rc = target_register_template(&ibmvscsis_ops);
4072         if (rc) {
4073                 pr_err("rc %d from target_register_template\n", rc);
4074                 goto unregister_class;
4075         }
4076
4077         rc = vio_register_driver(&ibmvscsis_driver);
4078         if (rc) {
4079                 pr_err("rc %d from vio_register_driver\n", rc);
4080                 goto unregister_target;
4081         }
4082
4083         return 0;
4084
4085 unregister_target:
4086         target_unregister_template(&ibmvscsis_ops);
4087 unregister_class:
4088         class_unregister(&ibmvscsis_class);
4089 out:
4090         return rc;
4091 }
4092
4093 static void __exit ibmvscsis_exit(void)
4094 {
4095         pr_info("Unregister IBM virtual SCSI host driver\n");
4096         vio_unregister_driver(&ibmvscsis_driver);
4097         target_unregister_template(&ibmvscsis_ops);
4098         class_unregister(&ibmvscsis_class);
4099 }
4100
4101 MODULE_DESCRIPTION("IBMVSCSIS fabric driver");
4102 MODULE_AUTHOR("Bryant G. Ly and Michael Cyr");
4103 MODULE_LICENSE("GPL");
4104 MODULE_VERSION(IBMVSCSIS_VERSION);
4105 module_init(ibmvscsis_init);
4106 module_exit(ibmvscsis_exit);