drivers/scsi/ibmvscsi/ibmvscsi.c

   1 /* ------------------------------------------------------------
   2  * ibmvscsi.c
   3  * (C) Copyright IBM Corporation 1994, 2004
   4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
   5  *          Santiago Leon (santil@us.ibm.com)
   6  *          Dave Boutcher (sleddog@us.ibm.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  21  * USA
  22  *
  23  * ------------------------------------------------------------
  24  * Emulation of a SCSI host adapter for Virtual I/O devices
  25  *
  26  * This driver supports the SCSI adapter implemented by the IBM
  27  * Power5 firmware.  That SCSI adapter is not a physical adapter,
  28  * but allows Linux SCSI peripheral drivers to directly
  29  * access devices in another logical partition on the physical system.
  30  *
  31  * The virtual adapter(s) are present in the open firmware device
  32  * tree just like real adapters.
  33  *
  34  * One of the capabilities provided on these systems is the ability
  35  * to DMA between partitions.  The architecture states that for VSCSI,
  36  * the server side is allowed to DMA to and from the client.  The client
  37  * is never trusted to DMA to or from the server directly.
  38  *
  39  * Messages are sent between partitions on a "Command/Response Queue"
  40  * (CRQ), which is just a buffer of 16 byte entries in the receiver's
  41  * Senders cannot access the buffer directly, but send messages by
  42  * making a hypervisor call and passing in the 16 bytes.  The hypervisor
  43  * puts the message in the next 16 byte space in round-robbin fashion,
  44  * turns on the high order bit of the message (the valid bit), and
  45  * generates an interrupt to the receiver (if interrupts are turned on.)
  46  * The receiver just turns off the valid bit when they have copied out
  47  * the message.
  48  *
  49  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
  50  * (IU) (as defined in the T10 standard available at www.t10.org), gets
  51  * a DMA address for the message, and sends it to the server as the
  52  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
  53  * including doing any additional data transfers.  When it is done, it
  54  * DMAs the SRP response back to the same address as the request came from,
  55  * and sends a CRQ message back to inform the client that the request has
  56  * completed.
  57  *
  58  * Note that some of the underlying infrastructure is different between
  59  * machines conforming to the "RS/6000 Platform Architecture" (RPA) and
  60  * the older iSeries hypervisor models.  To support both, some low level
  61  * routines have been broken out into rpa_vscsi.c and iseries_vscsi.c.
  62  * The Makefile should pick one, not two, not zero, of these.
  63  *
  64  * TODO: This is currently pretty tied to the IBM i/pSeries hypervisor
  65  * interfaces.  It would be really nice to abstract this above an RDMA
  66  * layer.
  67  */
  68
  69 #include <linux/module.h>
  70 #include <linux/moduleparam.h>
  71 #include <linux/dma-mapping.h>
  72 #include <linux/delay.h>
  73 #include <asm/firmware.h>
  74 #include <asm/vio.h>
  75 #include <asm/firmware.h>
  76 #include <scsi/scsi.h>
  77 #include <scsi/scsi_cmnd.h>
  78 #include <scsi/scsi_host.h>
  79 #include <scsi/scsi_device.h>
  80 #include <scsi/scsi_transport_srp.h>
  81 #include "ibmvscsi.h"
  82
  83 /* The values below are somewhat arbitrary default values, but
  84  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
  85  * Note that there are 3 bits of channel value, 6 bits of id, and
  86  * 5 bits of LUN.
  87  */
  88 static int max_id = 64;
  89 static int max_channel = 3;
  90 static int init_timeout = 5;
  91 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
  92
  93 static struct scsi_transport_template *ibmvscsi_transport_template;
  94
  95 #define IBMVSCSI_VERSION "1.5.8"
  96
  97 static struct ibmvscsi_ops *ibmvscsi_ops;
  98
  99 MODULE_DESCRIPTION("IBM Virtual SCSI");
 100 MODULE_AUTHOR("Dave Boutcher");
 101 MODULE_LICENSE("GPL");
 102 MODULE_VERSION(IBMVSCSI_VERSION);
 103
 104 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
 105 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
 106 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
 107 MODULE_PARM_DESC(max_channel, "Largest channel value");
 108 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
 109 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
 110 module_param_named(max_requests, max_requests, int, S_IRUGO | S_IWUSR);
 111 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
 112
 113 /* ------------------------------------------------------------
 114  * Routines for the event pool and event structs
 115  */
 116 /**
 117  * initialize_event_pool: - Allocates and initializes the event pool for a host
 118  * @pool:       event_pool to be initialized
 119  * @size:       Number of events in pool
 120  * @hostdata:   ibmvscsi_host_data who owns the event pool
 121  *
 122  * Returns zero on success.
 123 */
 124 static int initialize_event_pool(struct event_pool *pool,
 125                                  int size, struct ibmvscsi_host_data *hostdata)
 126 {
 127         int i;
 128
 129         pool->size = size;
 130         pool->next = 0;
 131         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
 132         if (!pool->events)
 133                 return -ENOMEM;
 134
 135         pool->iu_storage =
 136             dma_alloc_coherent(hostdata->dev,
 137                                pool->size * sizeof(*pool->iu_storage),
 138                                &pool->iu_token, 0);
 139         if (!pool->iu_storage) {
 140                 kfree(pool->events);
 141                 return -ENOMEM;
 142         }
 143
 144         for (i = 0; i < pool->size; ++i) {
 145                 struct srp_event_struct *evt = &pool->events[i];
 146                 memset(&evt->crq, 0x00, sizeof(evt->crq));
 147                 atomic_set(&evt->free, 1);
 148                 evt->crq.valid = 0x80;
 149                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
 150                 evt->crq.IU_data_ptr = pool->iu_token +
 151                         sizeof(*evt->xfer_iu) * i;
 152                 evt->xfer_iu = pool->iu_storage + i;
 153                 evt->hostdata = hostdata;
 154                 evt->ext_list = NULL;
 155                 evt->ext_list_token = 0;
 156         }
 157
 158         return 0;
 159 }
 160
 161 /**
 162  * release_event_pool: - Frees memory of an event pool of a host
 163  * @pool:       event_pool to be released
 164  * @hostdata:   ibmvscsi_host_data who owns the even pool
 165  *
 166  * Returns zero on success.
 167 */
 168 static void release_event_pool(struct event_pool *pool,
 169                                struct ibmvscsi_host_data *hostdata)
 170 {
 171         int i, in_use = 0;
 172         for (i = 0; i < pool->size; ++i) {
 173                 if (atomic_read(&pool->events[i].free) != 1)
 174                         ++in_use;
 175                 if (pool->events[i].ext_list) {
 176                         dma_free_coherent(hostdata->dev,
 177                                   SG_ALL * sizeof(struct srp_direct_buf),
 178                                   pool->events[i].ext_list,
 179                                   pool->events[i].ext_list_token);
 180                 }
 181         }
 182         if (in_use)
 183                 dev_warn(hostdata->dev, "releasing event pool with %d "
 184                          "events still in use?\n", in_use);
 185         kfree(pool->events);
 186         dma_free_coherent(hostdata->dev,
 187                           pool->size * sizeof(*pool->iu_storage),
 188                           pool->iu_storage, pool->iu_token);
 189 }
 190
 191 /**
 192  * valid_event_struct: - Determines if event is valid.
 193  * @pool:       event_pool that contains the event
 194  * @evt:        srp_event_struct to be checked for validity
 195  *
 196  * Returns zero if event is invalid, one otherwise.
 197 */
 198 static int valid_event_struct(struct event_pool *pool,
 199                                 struct srp_event_struct *evt)
 200 {
 201         int index = evt - pool->events;
 202         if (index < 0 || index >= pool->size)   /* outside of bounds */
 203                 return 0;
 204         if (evt != pool->events + index)        /* unaligned */
 205                 return 0;
 206         return 1;
 207 }
 208
 209 /**
 210  * ibmvscsi_free-event_struct: - Changes status of event to "free"
 211  * @pool:       event_pool that contains the event
 212  * @evt:        srp_event_struct to be modified
 213  *
 214 */
 215 static void free_event_struct(struct event_pool *pool,
 216                                        struct srp_event_struct *evt)
 217 {
 218         if (!valid_event_struct(pool, evt)) {
 219                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
 220                         "(not in pool %p)\n", evt, pool->events);
 221                 return;
 222         }
 223         if (atomic_inc_return(&evt->free) != 1) {
 224                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
 225                         "which is not in use!\n", evt);
 226                 return;
 227         }
 228 }
 229
 230 /**
 231  * get_evt_struct: - Gets the next free event in pool
 232  * @pool:       event_pool that contains the events to be searched
 233  *
 234  * Returns the next event in "free" state, and NULL if none are free.
 235  * Note that no synchronization is done here, we assume the host_lock
 236  * will syncrhonze things.
 237 */
 238 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
 239 {
 240         int i;
 241         int poolsize = pool->size;
 242         int offset = pool->next;
 243
 244         for (i = 0; i < poolsize; i++) {
 245                 offset = (offset + 1) % poolsize;
 246                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
 247                         pool->next = offset;
 248                         return &pool->events[offset];
 249                 }
 250         }
 251
 252         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
 253         return NULL;
 254 }
 255
 256 /**
 257  * init_event_struct: Initialize fields in an event struct that are always
 258  *                    required.
 259  * @evt:        The event
 260  * @done:       Routine to call when the event is responded to
 261  * @format:     SRP or MAD format
 262  * @timeout:    timeout value set in the CRQ
 263  */
 264 static void init_event_struct(struct srp_event_struct *evt_struct,
 265                               void (*done) (struct srp_event_struct *),
 266                               u8 format,
 267                               int timeout)
 268 {
 269         evt_struct->cmnd = NULL;
 270         evt_struct->cmnd_done = NULL;
 271         evt_struct->sync_srp = NULL;
 272         evt_struct->crq.format = format;
 273         evt_struct->crq.timeout = timeout;
 274         evt_struct->done = done;
 275 }
 276
 277 /* ------------------------------------------------------------
 278  * Routines for receiving SCSI responses from the hosting partition
 279  */
 280
 281 /**
 282  * set_srp_direction: Set the fields in the srp related to data
 283  *     direction and number of buffers based on the direction in
 284  *     the scsi_cmnd and the number of buffers
 285  */
 286 static void set_srp_direction(struct scsi_cmnd *cmd,
 287                               struct srp_cmd *srp_cmd,
 288                               int numbuf)
 289 {
 290         u8 fmt;
 291
 292         if (numbuf == 0)
 293                 return;
 294
 295         if (numbuf == 1)
 296                 fmt = SRP_DATA_DESC_DIRECT;
 297         else {
 298                 fmt = SRP_DATA_DESC_INDIRECT;
 299                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
 300
 301                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
 302                         srp_cmd->data_out_desc_cnt = numbuf;
 303                 else
 304                         srp_cmd->data_in_desc_cnt = numbuf;
 305         }
 306
 307         if (cmd->sc_data_direction == DMA_TO_DEVICE)
 308                 srp_cmd->buf_fmt = fmt << 4;
 309         else
 310                 srp_cmd->buf_fmt = fmt;
 311 }
 312
 313 static void unmap_sg_list(int num_entries,
 314                 struct device *dev,
 315                 struct srp_direct_buf *md)
 316 {
 317         int i;
 318
 319         for (i = 0; i < num_entries; ++i)
 320                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
 321 }
 322
 323 /**
 324  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
 325  * @cmd:        srp_cmd whose additional_data member will be unmapped
 326  * @dev:        device for which the memory is mapped
 327  *
 328 */
 329 static void unmap_cmd_data(struct srp_cmd *cmd,
 330                            struct srp_event_struct *evt_struct,
 331                            struct device *dev)
 332 {
 333         u8 out_fmt, in_fmt;
 334
 335         out_fmt = cmd->buf_fmt >> 4;
 336         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
 337
 338         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
 339                 return;
 340         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
 341                  in_fmt == SRP_DATA_DESC_DIRECT) {
 342                 struct srp_direct_buf *data =
 343                         (struct srp_direct_buf *) cmd->add_data;
 344                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
 345         } else {
 346                 struct srp_indirect_buf *indirect =
 347                         (struct srp_indirect_buf *) cmd->add_data;
 348                 int num_mapped = indirect->table_desc.len /
 349                         sizeof(struct srp_direct_buf);
 350
 351                 if (num_mapped <= MAX_INDIRECT_BUFS) {
 352                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
 353                         return;
 354                 }
 355
 356                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
 357         }
 358 }
 359
 360 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
 361                        struct srp_direct_buf *md)
 362 {
 363         int i;
 364         struct scatterlist *sg;
 365         u64 total_length = 0;
 366
 367         scsi_for_each_sg(cmd, sg, nseg, i) {
 368                 struct srp_direct_buf *descr = md + i;
 369                 descr->va = sg_dma_address(sg);
 370                 descr->len = sg_dma_len(sg);
 371                 descr->key = 0;
 372                 total_length += sg_dma_len(sg);
 373         }
 374         return total_length;
 375 }
 376
 377 /**
 378  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
 379  * @cmd:        Scsi_Cmnd with the scatterlist
 380  * @srp_cmd:    srp_cmd that contains the memory descriptor
 381  * @dev:        device for which to map dma memory
 382  *
 383  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 384  * Returns 1 on success.
 385 */
 386 static int map_sg_data(struct scsi_cmnd *cmd,
 387                        struct srp_event_struct *evt_struct,
 388                        struct srp_cmd *srp_cmd, struct device *dev)
 389 {
 390
 391         int sg_mapped;
 392         u64 total_length = 0;
 393         struct srp_direct_buf *data =
 394                 (struct srp_direct_buf *) srp_cmd->add_data;
 395         struct srp_indirect_buf *indirect =
 396                 (struct srp_indirect_buf *) data;
 397
 398         sg_mapped = scsi_dma_map(cmd);
 399         if (!sg_mapped)
 400                 return 1;
 401         else if (sg_mapped < 0)
 402                 return 0;
 403
 404         set_srp_direction(cmd, srp_cmd, sg_mapped);
 405
 406         /* special case; we can use a single direct descriptor */
 407         if (sg_mapped == 1) {
 408                 map_sg_list(cmd, sg_mapped, data);
 409                 return 1;
 410         }
 411
 412         indirect->table_desc.va = 0;
 413         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
 414         indirect->table_desc.key = 0;
 415
 416         if (sg_mapped <= MAX_INDIRECT_BUFS) {
 417                 total_length = map_sg_list(cmd, sg_mapped,
 418                                            &indirect->desc_list[0]);
 419                 indirect->len = total_length;
 420                 return 1;
 421         }
 422
 423         /* get indirect table */
 424         if (!evt_struct->ext_list) {
 425                 evt_struct->ext_list = (struct srp_direct_buf *)
 426                         dma_alloc_coherent(dev,
 427                                            SG_ALL * sizeof(struct srp_direct_buf),
 428                                            &evt_struct->ext_list_token, 0);
 429                 if (!evt_struct->ext_list) {
 430                         if (!firmware_has_feature(FW_FEATURE_CMO))
 431                                 sdev_printk(KERN_ERR, cmd->device,
 432                                             "Can't allocate memory "
 433                                             "for indirect table\n");
 434                         return 0;
 435                 }
 436         }
 437
 438         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
 439
 440         indirect->len = total_length;
 441         indirect->table_desc.va = evt_struct->ext_list_token;
 442         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
 443         memcpy(indirect->desc_list, evt_struct->ext_list,
 444                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
 445         return 1;
 446 }
 447
 448 /**
 449  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
 450  * @cmd:        struct scsi_cmnd with the memory to be mapped
 451  * @srp_cmd:    srp_cmd that contains the memory descriptor
 452  * @dev:        dma device for which to map dma memory
 453  *
 454  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
 455  * Returns 1 on success.
 456 */
 457 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
 458                                 struct srp_event_struct *evt_struct,
 459                                 struct srp_cmd *srp_cmd, struct device *dev)
 460 {
 461         switch (cmd->sc_data_direction) {
 462         case DMA_FROM_DEVICE:
 463         case DMA_TO_DEVICE:
 464                 break;
 465         case DMA_NONE:
 466                 return 1;
 467         case DMA_BIDIRECTIONAL:
 468                 sdev_printk(KERN_ERR, cmd->device,
 469                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
 470                 return 0;
 471         default:
 472                 sdev_printk(KERN_ERR, cmd->device,
 473                             "Unknown data direction 0x%02x; can't map!\n",
 474                             cmd->sc_data_direction);
 475                 return 0;
 476         }
 477
 478         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
 479 }
 480
 481 /**
 482  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
 483  * @hostdata:    the adapter
 484  */
 485 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
 486 {
 487         struct srp_event_struct *tmp_evt, *pos;
 488         unsigned long flags;
 489
 490         spin_lock_irqsave(hostdata->host->host_lock, flags);
 491         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
 492                 list_del(&tmp_evt->list);
 493                 del_timer(&tmp_evt->timer);
 494                 if (tmp_evt->cmnd) {
 495                         tmp_evt->cmnd->result = (error_code << 16);
 496                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
 497                                        tmp_evt,
 498                                        tmp_evt->hostdata->dev);
 499                         if (tmp_evt->cmnd_done)
 500                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
 501                 } else if (tmp_evt->done)
 502                         tmp_evt->done(tmp_evt);
 503                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
 504         }
 505         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 506 }
 507
 508 /**
 509  * ibmvscsi_reset_host - Reset the connection to the server
 510  * @hostdata:   struct ibmvscsi_host_data to reset
 511 */
 512 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
 513 {
 514         scsi_block_requests(hostdata->host);
 515         atomic_set(&hostdata->request_limit, 0);
 516
 517         purge_requests(hostdata, DID_ERROR);
 518         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata)) ||
 519             (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0)) ||
 520             (vio_enable_interrupts(to_vio_dev(hostdata->dev)))) {
 521                 atomic_set(&hostdata->request_limit, -1);
 522                 dev_err(hostdata->dev, "error after reset\n");
 523         }
 524
 525         scsi_unblock_requests(hostdata->host);
 526 }
 527
 528 /**
 529  * ibmvscsi_timeout - Internal command timeout handler
 530  * @evt_struct: struct srp_event_struct that timed out
 531  *
 532  * Called when an internally generated command times out
 533 */
 534 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
 535 {
 536         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 537
 538         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
 539                 evt_struct->iu.srp.cmd.opcode);
 540
 541         ibmvscsi_reset_host(hostdata);
 542 }
 543
 544
 545 /* ------------------------------------------------------------
 546  * Routines for sending and receiving SRPs
 547  */
 548 /**
 549  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 550  * @evt_struct: evt_struct to be sent
 551  * @hostdata:   ibmvscsi_host_data of host
 552  * @timeout:    timeout in seconds - 0 means do not time command
 553  *
 554  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 555  * Note that this routine assumes that host_lock is held for synchronization
 556 */
 557 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 558                                    struct ibmvscsi_host_data *hostdata,
 559                                    unsigned long timeout)
 560 {
 561         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 562         int request_status = 0;
 563         int rc;
 564
 565         /* If we have exhausted our request limit, just fail this request,
 566          * unless it is for a reset or abort.
 567          * Note that there are rare cases involving driver generated requests
 568          * (such as task management requests) that the mid layer may think we
 569          * can handle more requests (can_queue) when we actually can't
 570          */
 571         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
 572                 request_status =
 573                         atomic_dec_if_positive(&hostdata->request_limit);
 574                 /* If request limit was -1 when we started, it is now even
 575                  * less than that
 576                  */
 577                 if (request_status < -1)
 578                         goto send_error;
 579                 /* Otherwise, we may have run out of requests. */
 580                 /* If request limit was 0 when we started the adapter is in the
 581                  * process of performing a login with the server adapter, or
 582                  * we may have run out of requests.
 583                  */
 584                 else if (request_status == -1 &&
 585                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
 586                         goto send_busy;
 587                 /* Abort and reset calls should make it through.
 588                  * Nothing except abort and reset should use the last two
 589                  * slots unless we had two or less to begin with.
 590                  */
 591                 else if (request_status < 2 &&
 592                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
 593                         /* In the case that we have less than two requests
 594                          * available, check the server limit as a combination
 595                          * of the request limit and the number of requests
 596                          * in-flight (the size of the send list).  If the
 597                          * server limit is greater than 2, return busy so
 598                          * that the last two are reserved for reset and abort.
 599                          */
 600                         int server_limit = request_status;
 601                         struct srp_event_struct *tmp_evt;
 602
 603                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 604                                 server_limit++;
 605                         }
 606
 607                         if (server_limit > 2)
 608                                 goto send_busy;
 609                 }
 610         }
 611
 612         /* Copy the IU into the transfer area */
 613         *evt_struct->xfer_iu = evt_struct->iu;
 614         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 615
 616         /* Add this to the sent list.  We need to do this
 617          * before we actually send
 618          * in case it comes back REALLY fast
 619          */
 620         list_add_tail(&evt_struct->list, &hostdata->sent);
 621
 622         init_timer(&evt_struct->timer);
 623         if (timeout) {
 624                 evt_struct->timer.data = (unsigned long) evt_struct;
 625                 evt_struct->timer.expires = jiffies + (timeout * HZ);
 626                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
 627                 add_timer(&evt_struct->timer);
 628         }
 629
 630         if ((rc =
 631              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 632                 list_del(&evt_struct->list);
 633                 del_timer(&evt_struct->timer);
 634
 635                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
 636                  * Firmware will send a CRQ with a transport event (0xFF) to
 637                  * tell this client what has happened to the transport.  This
 638                  * will be handled in ibmvscsi_handle_crq()
 639                  */
 640                 if (rc == H_CLOSED) {
 641                         dev_warn(hostdata->dev, "send warning. "
 642                                  "Receive queue closed, will retry.\n");
 643                         goto send_busy;
 644                 }
 645                 dev_err(hostdata->dev, "send error %d\n", rc);
 646                 atomic_inc(&hostdata->request_limit);
 647                 goto send_error;
 648         }
 649
 650         return 0;
 651
 652  send_busy:
 653         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 654
 655         free_event_struct(&hostdata->pool, evt_struct);
 656         if (request_status != -1)
 657                 atomic_inc(&hostdata->request_limit);
 658         return SCSI_MLQUEUE_HOST_BUSY;
 659
 660  send_error:
 661         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 662
 663         if (evt_struct->cmnd != NULL) {
 664                 evt_struct->cmnd->result = DID_ERROR << 16;
 665                 evt_struct->cmnd_done(evt_struct->cmnd);
 666         } else if (evt_struct->done)
 667                 evt_struct->done(evt_struct);
 668
 669         free_event_struct(&hostdata->pool, evt_struct);
 670         return 0;
 671 }
 672
 673 /**
 674  * handle_cmd_rsp: -  Handle responses from commands
 675  * @evt_struct: srp_event_struct to be handled
 676  *
 677  * Used as a callback by when sending scsi cmds.
 678  * Gets called by ibmvscsi_handle_crq()
 679 */
 680 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 681 {
 682         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 683         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 684
 685         if (unlikely(rsp->opcode != SRP_RSP)) {
 686                 if (printk_ratelimit())
 687                         dev_warn(evt_struct->hostdata->dev,
 688                                  "bad SRP RSP type %d\n", rsp->opcode);
 689         }
 690
 691         if (cmnd) {
 692                 cmnd->result |= rsp->status;
 693                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 694                         memcpy(cmnd->sense_buffer,
 695                                rsp->data,
 696                                rsp->sense_data_len);
 697                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 698                                evt_struct,
 699                                evt_struct->hostdata->dev);
 700
 701                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 702                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
 703                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 704                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
 705         }
 706
 707         if (evt_struct->cmnd_done)
 708                 evt_struct->cmnd_done(cmnd);
 709 }
 710
 711 /**
 712  * lun_from_dev: - Returns the lun of the scsi device
 713  * @dev:        struct scsi_device
 714  *
 715 */
 716 static inline u16 lun_from_dev(struct scsi_device *dev)
 717 {
 718         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 719 }
 720
 721 /**
 722  * ibmvscsi_queue: - The queuecommand function of the scsi template
 723  * @cmd:        struct scsi_cmnd to be executed
 724  * @done:       Callback function to be called when cmd is completed
 725 */
 726 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
 727                                  void (*done) (struct scsi_cmnd *))
 728 {
 729         struct srp_cmd *srp_cmd;
 730         struct srp_event_struct *evt_struct;
 731         struct srp_indirect_buf *indirect;
 732         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
 733         u16 lun = lun_from_dev(cmnd->device);
 734         u8 out_fmt, in_fmt;
 735
 736         cmnd->result = (DID_OK << 16);
 737         evt_struct = get_event_struct(&hostdata->pool);
 738         if (!evt_struct)
 739                 return SCSI_MLQUEUE_HOST_BUSY;
 740
 741         /* Set up the actual SRP IU */
 742         srp_cmd = &evt_struct->iu.srp.cmd;
 743         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 744         srp_cmd->opcode = SRP_CMD;
 745         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
 746         srp_cmd->lun = ((u64) lun) << 48;
 747
 748         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 749                 if (!firmware_has_feature(FW_FEATURE_CMO))
 750                         sdev_printk(KERN_ERR, cmnd->device,
 751                                     "couldn't convert cmd to srp_cmd\n");
 752                 free_event_struct(&hostdata->pool, evt_struct);
 753                 return SCSI_MLQUEUE_HOST_BUSY;
 754         }
 755
 756         init_event_struct(evt_struct,
 757                           handle_cmd_rsp,
 758                           VIOSRP_SRP_FORMAT,
 759                           cmnd->request->timeout/HZ);
 760
 761         evt_struct->cmnd = cmnd;
 762         evt_struct->cmnd_done = done;
 763
 764         /* Fix up dma address of the buffer itself */
 765         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 766         out_fmt = srp_cmd->buf_fmt >> 4;
 767         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 768         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 769              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 770             indirect->table_desc.va == 0) {
 771                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 772                         offsetof(struct srp_cmd, add_data) +
 773                         offsetof(struct srp_indirect_buf, desc_list);
 774         }
 775
 776         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
 777 }
 778
 779 /* ------------------------------------------------------------
 780  * Routines for driver initialization
 781  */
 782 /**
 783  * adapter_info_rsp: - Handle response to MAD adapter info request
 784  * @evt_struct: srp_event_struct with the response
 785  *
 786  * Used as a "done" callback by when sending adapter_info. Gets called
 787  * by ibmvscsi_handle_crq()
 788 */
 789 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
 790 {
 791         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 792         dma_unmap_single(hostdata->dev,
 793                          evt_struct->iu.mad.adapter_info.buffer,
 794                          evt_struct->iu.mad.adapter_info.common.length,
 795                          DMA_BIDIRECTIONAL);
 796
 797         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
 798                 dev_err(hostdata->dev, "error %d getting adapter info\n",
 799                         evt_struct->xfer_iu->mad.adapter_info.common.status);
 800         } else {
 801                 dev_info(hostdata->dev, "host srp version: %s, "
 802                          "host partition %s (%d), OS %d, max io %u\n",
 803                          hostdata->madapter_info.srp_version,
 804                          hostdata->madapter_info.partition_name,
 805                          hostdata->madapter_info.partition_number,
 806                          hostdata->madapter_info.os_type,
 807                          hostdata->madapter_info.port_max_txu[0]);
 808
 809                 if (hostdata->madapter_info.port_max_txu[0])
 810                         hostdata->host->max_sectors =
 811                                 hostdata->madapter_info.port_max_txu[0] >> 9;
 812
 813                 if (hostdata->madapter_info.os_type == 3 &&
 814                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
 815                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
 816                                 hostdata->madapter_info.srp_version);
 817                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
 818                                 MAX_INDIRECT_BUFS);
 819                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
 820                 }
 821         }
 822 }
 823
 824 /**
 825  * send_mad_adapter_info: - Sends the mad adapter info request
 826  *      and stores the result so it can be retrieved with
 827  *      sysfs.  We COULD consider causing a failure if the
 828  *      returned SRP version doesn't match ours.
 829  * @hostdata:   ibmvscsi_host_data of host
 830  *
 831  * Returns zero if successful.
 832 */
 833 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
 834 {
 835         struct viosrp_adapter_info *req;
 836         struct srp_event_struct *evt_struct;
 837         unsigned long flags;
 838         dma_addr_t addr;
 839
 840         evt_struct = get_event_struct(&hostdata->pool);
 841         if (!evt_struct) {
 842                 dev_err(hostdata->dev,
 843                         "couldn't allocate an event for ADAPTER_INFO_REQ!\n");
 844                 return;
 845         }
 846
 847         init_event_struct(evt_struct,
 848                           adapter_info_rsp,
 849                           VIOSRP_MAD_FORMAT,
 850                           init_timeout);
 851
 852         req = &evt_struct->iu.mad.adapter_info;
 853         memset(req, 0x00, sizeof(*req));
 854
 855         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
 856         req->common.length = sizeof(hostdata->madapter_info);
 857         req->buffer = addr = dma_map_single(hostdata->dev,
 858                                             &hostdata->madapter_info,
 859                                             sizeof(hostdata->madapter_info),
 860                                             DMA_BIDIRECTIONAL);
 861
 862         if (dma_mapping_error(hostdata->dev, req->buffer)) {
 863                 if (!firmware_has_feature(FW_FEATURE_CMO))
 864                         dev_err(hostdata->dev,
 865                                 "Unable to map request_buffer for "
 866                                 "adapter_info!\n");
 867                 free_event_struct(&hostdata->pool, evt_struct);
 868                 return;
 869         }
 870
 871         spin_lock_irqsave(hostdata->host->host_lock, flags);
 872         if (ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2)) {
 873                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
 874                 dma_unmap_single(hostdata->dev,
 875                                  addr,
 876                                  sizeof(hostdata->madapter_info),
 877                                  DMA_BIDIRECTIONAL);
 878         }
 879         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 880 };
 881
 882 /**
 883  * login_rsp: - Handle response to SRP login request
 884  * @evt_struct: srp_event_struct with the response
 885  *
 886  * Used as a "done" callback by when sending srp_login. Gets called
 887  * by ibmvscsi_handle_crq()
 888 */
 889 static void login_rsp(struct srp_event_struct *evt_struct)
 890 {
 891         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 892         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 893         case SRP_LOGIN_RSP:     /* it worked! */
 894                 break;
 895         case SRP_LOGIN_REJ:     /* refused! */
 896                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
 897                          evt_struct->xfer_iu->srp.login_rej.reason);
 898                 /* Login failed.  */
 899                 atomic_set(&hostdata->request_limit, -1);
 900                 return;
 901         default:
 902                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
 903                         evt_struct->xfer_iu->srp.login_rsp.opcode);
 904                 /* Login failed.  */
 905                 atomic_set(&hostdata->request_limit, -1);
 906                 return;
 907         }
 908
 909         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
 910
 911         if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta < 0)
 912                 dev_err(hostdata->dev, "Invalid request_limit.\n");
 913
 914         /* Now we know what the real request-limit is.
 915          * This value is set rather than added to request_limit because
 916          * request_limit could have been set to -1 by this client.
 917          */
 918         atomic_set(&hostdata->request_limit,
 919                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 920
 921         /* If we had any pending I/Os, kick them */
 922         scsi_unblock_requests(hostdata->host);
 923
 924         send_mad_adapter_info(hostdata);
 925         return;
 926 }
 927
 928 /**
 929  * send_srp_login: - Sends the srp login
 930  * @hostdata:   ibmvscsi_host_data of host
 931  *
 932  * Returns zero if successful.
 933 */
 934 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 935 {
 936         int rc;
 937         unsigned long flags;
 938         struct srp_login_req *login;
 939         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 940         if (!evt_struct) {
 941                 dev_err(hostdata->dev, "couldn't allocate an event for login req!\n");
 942                 return FAILED;
 943         }
 944
 945         init_event_struct(evt_struct,
 946                           login_rsp,
 947                           VIOSRP_SRP_FORMAT,
 948                           init_timeout);
 949
 950         login = &evt_struct->iu.srp.login_req;
 951         memset(login, 0x00, sizeof(struct srp_login_req));
 952         login->opcode = SRP_LOGIN_REQ;
 953         login->req_it_iu_len = sizeof(union srp_iu);
 954         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 955
 956         spin_lock_irqsave(hostdata->host->host_lock, flags);
 957         /* Start out with a request limit of 0, since this is negotiated in
 958          * the login request we are just sending and login requests always
 959          * get sent by the driver regardless of request_limit.
 960          */
 961         atomic_set(&hostdata->request_limit, 0);
 962
 963         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2);
 964         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 965         dev_info(hostdata->dev, "sent SRP login\n");
 966         return rc;
 967 };
 968
 969 /**
 970  * sync_completion: Signal that a synchronous command has completed
 971  * Note that after returning from this call, the evt_struct is freed.
 972  * the caller waiting on this completion shouldn't touch the evt_struct
 973  * again.
 974  */
 975 static void sync_completion(struct srp_event_struct *evt_struct)
 976 {
 977         /* copy the response back */
 978         if (evt_struct->sync_srp)
 979                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
 980
 981         complete(&evt_struct->comp);
 982 }
 983
 984 /**
 985  * ibmvscsi_abort: Abort a command...from scsi host template
 986  * send this over to the server and wait synchronously for the response
 987  */
 988 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
 989 {
 990         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
 991         struct srp_tsk_mgmt *tsk_mgmt;
 992         struct srp_event_struct *evt;
 993         struct srp_event_struct *tmp_evt, *found_evt;
 994         union viosrp_iu srp_rsp;
 995         int rsp_rc;
 996         unsigned long flags;
 997         u16 lun = lun_from_dev(cmd->device);
 998         unsigned long wait_switch = 0;
 999
1000         /* First, find this command in our sent list so we can figure
1001          * out the correct tag
1002          */
1003         spin_lock_irqsave(hostdata->host->host_lock, flags);
1004         wait_switch = jiffies + (init_timeout * HZ);
1005         do {
1006                 found_evt = NULL;
1007                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1008                         if (tmp_evt->cmnd == cmd) {
1009                                 found_evt = tmp_evt;
1010                                 break;
1011                         }
1012                 }
1013
1014                 if (!found_evt) {
1015                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1016                         return SUCCESS;
1017                 }
1018
1019                 evt = get_event_struct(&hostdata->pool);
1020                 if (evt == NULL) {
1021                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1022                         sdev_printk(KERN_ERR, cmd->device,
1023                                 "failed to allocate abort event\n");
1024                         return FAILED;
1025                 }
1026
1027                 init_event_struct(evt,
1028                                   sync_completion,
1029                                   VIOSRP_SRP_FORMAT,
1030                                   init_timeout);
1031
1032                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1033
1034                 /* Set up an abort SRP command */
1035                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1036                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1037                 tsk_mgmt->lun = ((u64) lun) << 48;
1038                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1039                 tsk_mgmt->task_tag = (u64) found_evt;
1040
1041                 evt->sync_srp = &srp_rsp;
1042
1043                 init_completion(&evt->comp);
1044                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, init_timeout * 2);
1045
1046                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1047                         break;
1048
1049                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1050                 msleep(10);
1051                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1052         } while (time_before(jiffies, wait_switch));
1053
1054         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1055
1056         if (rsp_rc != 0) {
1057                 sdev_printk(KERN_ERR, cmd->device,
1058                             "failed to send abort() event. rc=%d\n", rsp_rc);
1059                 return FAILED;
1060         }
1061
1062         sdev_printk(KERN_INFO, cmd->device,
1063                     "aborting command. lun 0x%lx, tag 0x%lx\n",
1064                     (((u64) lun) << 48), (u64) found_evt);
1065
1066         wait_for_completion(&evt->comp);
1067
1068         /* make sure we got a good response */
1069         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1070                 if (printk_ratelimit())
1071                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1072                                     srp_rsp.srp.rsp.opcode);
1073                 return FAILED;
1074         }
1075
1076         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1077                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1078         else
1079                 rsp_rc = srp_rsp.srp.rsp.status;
1080
1081         if (rsp_rc) {
1082                 if (printk_ratelimit())
1083                         sdev_printk(KERN_WARNING, cmd->device,
1084                                     "abort code %d for task tag 0x%lx\n",
1085                                     rsp_rc, tsk_mgmt->task_tag);
1086                 return FAILED;
1087         }
1088
1089         /* Because we dropped the spinlock above, it's possible
1090          * The event is no longer in our list.  Make sure it didn't
1091          * complete while we were aborting
1092          */
1093         spin_lock_irqsave(hostdata->host->host_lock, flags);
1094         found_evt = NULL;
1095         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1096                 if (tmp_evt->cmnd == cmd) {
1097                         found_evt = tmp_evt;
1098                         break;
1099                 }
1100         }
1101
1102         if (found_evt == NULL) {
1103                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1104                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%lx completed\n",
1105                             tsk_mgmt->task_tag);
1106                 return SUCCESS;
1107         }
1108
1109         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%lx\n",
1110                     tsk_mgmt->task_tag);
1111
1112         cmd->result = (DID_ABORT << 16);
1113         list_del(&found_evt->list);
1114         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1115                        found_evt->hostdata->dev);
1116         free_event_struct(&found_evt->hostdata->pool, found_evt);
1117         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1118         atomic_inc(&hostdata->request_limit);
1119         return SUCCESS;
1120 }
1121
1122 /**
1123  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1124  * template send this over to the server and wait synchronously for the
1125  * response
1126  */
1127 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1128 {
1129         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1130         struct srp_tsk_mgmt *tsk_mgmt;
1131         struct srp_event_struct *evt;
1132         struct srp_event_struct *tmp_evt, *pos;
1133         union viosrp_iu srp_rsp;
1134         int rsp_rc;
1135         unsigned long flags;
1136         u16 lun = lun_from_dev(cmd->device);
1137         unsigned long wait_switch = 0;
1138
1139         spin_lock_irqsave(hostdata->host->host_lock, flags);
1140         wait_switch = jiffies + (init_timeout * HZ);
1141         do {
1142                 evt = get_event_struct(&hostdata->pool);
1143                 if (evt == NULL) {
1144                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1145                         sdev_printk(KERN_ERR, cmd->device,
1146                                 "failed to allocate reset event\n");
1147                         return FAILED;
1148                 }
1149
1150                 init_event_struct(evt,
1151                                   sync_completion,
1152                                   VIOSRP_SRP_FORMAT,
1153                                   init_timeout);
1154
1155                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1156
1157                 /* Set up a lun reset SRP command */
1158                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1159                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1160                 tsk_mgmt->lun = ((u64) lun) << 48;
1161                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1162
1163                 evt->sync_srp = &srp_rsp;
1164
1165                 init_completion(&evt->comp);
1166                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, init_timeout * 2);
1167
1168                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1169                         break;
1170
1171                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1172                 msleep(10);
1173                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1174         } while (time_before(jiffies, wait_switch));
1175
1176         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1177
1178         if (rsp_rc != 0) {
1179                 sdev_printk(KERN_ERR, cmd->device,
1180                             "failed to send reset event. rc=%d\n", rsp_rc);
1181                 return FAILED;
1182         }
1183
1184         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%lx\n",
1185                     (((u64) lun) << 48));
1186
1187         wait_for_completion(&evt->comp);
1188
1189         /* make sure we got a good response */
1190         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1191                 if (printk_ratelimit())
1192                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1193                                     srp_rsp.srp.rsp.opcode);
1194                 return FAILED;
1195         }
1196
1197         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1198                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1199         else
1200                 rsp_rc = srp_rsp.srp.rsp.status;
1201
1202         if (rsp_rc) {
1203                 if (printk_ratelimit())
1204                         sdev_printk(KERN_WARNING, cmd->device,
1205                                     "reset code %d for task tag 0x%lx\n",
1206                                     rsp_rc, tsk_mgmt->task_tag);
1207                 return FAILED;
1208         }
1209
1210         /* We need to find all commands for this LUN that have not yet been
1211          * responded to, and fail them with DID_RESET
1212          */
1213         spin_lock_irqsave(hostdata->host->host_lock, flags);
1214         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1215                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1216                         if (tmp_evt->cmnd)
1217                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1218                         list_del(&tmp_evt->list);
1219                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1220                                        tmp_evt->hostdata->dev);
1221                         free_event_struct(&tmp_evt->hostdata->pool,
1222                                                    tmp_evt);
1223                         atomic_inc(&hostdata->request_limit);
1224                         if (tmp_evt->cmnd_done)
1225                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1226                         else if (tmp_evt->done)
1227                                 tmp_evt->done(tmp_evt);
1228                 }
1229         }
1230         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1231         return SUCCESS;
1232 }
1233
1234 /**
1235  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1236  * @cmd:        struct scsi_cmnd having problems
1237 */
1238 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1239 {
1240         unsigned long wait_switch = 0;
1241         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1242
1243         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1244
1245         ibmvscsi_reset_host(hostdata);
1246
1247         for (wait_switch = jiffies + (init_timeout * HZ);
1248              time_before(jiffies, wait_switch) &&
1249                      atomic_read(&hostdata->request_limit) < 2;) {
1250
1251                 msleep(10);
1252         }
1253
1254         if (atomic_read(&hostdata->request_limit) <= 0)
1255                 return FAILED;
1256
1257         return SUCCESS;
1258 }
1259
1260 /**
1261  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1262  * @crq:        Command/Response queue
1263  * @hostdata:   ibmvscsi_host_data of host
1264  *
1265 */
1266 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1267                          struct ibmvscsi_host_data *hostdata)
1268 {
1269         long rc;
1270         unsigned long flags;
1271         struct srp_event_struct *evt_struct =
1272             (struct srp_event_struct *)crq->IU_data_ptr;
1273         switch (crq->valid) {
1274         case 0xC0:              /* initialization */
1275                 switch (crq->format) {
1276                 case 0x01:      /* Initialization message */
1277                         dev_info(hostdata->dev, "partner initialized\n");
1278                         /* Send back a response */
1279                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1280                                                          0xC002000000000000LL, 0)) == 0) {
1281                                 /* Now login */
1282                                 send_srp_login(hostdata);
1283                         } else {
1284                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1285                         }
1286
1287                         break;
1288                 case 0x02:      /* Initialization response */
1289                         dev_info(hostdata->dev, "partner initialization complete\n");
1290
1291                         /* Now login */
1292                         send_srp_login(hostdata);
1293                         break;
1294                 default:
1295                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1296                 }
1297                 return;
1298         case 0xFF:      /* Hypervisor telling us the connection is closed */
1299                 scsi_block_requests(hostdata->host);
1300                 atomic_set(&hostdata->request_limit, 0);
1301                 if (crq->format == 0x06) {
1302                         /* We need to re-setup the interpartition connection */
1303                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1304                         purge_requests(hostdata, DID_REQUEUE);
1305                         if ((ibmvscsi_ops->reenable_crq_queue(&hostdata->queue,
1306                                                               hostdata)) ||
1307                             (ibmvscsi_ops->send_crq(hostdata,
1308                                                     0xC001000000000000LL, 0))) {
1309                                         atomic_set(&hostdata->request_limit,
1310                                                    -1);
1311                                         dev_err(hostdata->dev, "error after enable\n");
1312                         }
1313                 } else {
1314                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1315                                 crq->format);
1316
1317                         purge_requests(hostdata, DID_ERROR);
1318                         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue,
1319                                                            hostdata)) ||
1320                             (ibmvscsi_ops->send_crq(hostdata,
1321                                                     0xC001000000000000LL, 0))) {
1322                                         atomic_set(&hostdata->request_limit,
1323                                                    -1);
1324                                         dev_err(hostdata->dev, "error after reset\n");
1325                         }
1326                 }
1327                 scsi_unblock_requests(hostdata->host);
1328                 return;
1329         case 0x80:              /* real payload */
1330                 break;
1331         default:
1332                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1333                         crq->valid);
1334                 return;
1335         }
1336
1337         /* The only kind of payload CRQs we should get are responses to
1338          * things we send. Make sure this response is to something we
1339          * actually sent
1340          */
1341         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1342                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1343                        (void *)crq->IU_data_ptr);
1344                 return;
1345         }
1346
1347         if (atomic_read(&evt_struct->free)) {
1348                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1349                         (void *)crq->IU_data_ptr);
1350                 return;
1351         }
1352
1353         if (crq->format == VIOSRP_SRP_FORMAT)
1354                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1355                            &hostdata->request_limit);
1356
1357         del_timer(&evt_struct->timer);
1358
1359         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1360                 evt_struct->cmnd->result = DID_ERROR << 16;
1361         if (evt_struct->done)
1362                 evt_struct->done(evt_struct);
1363         else
1364                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1365
1366         /*
1367          * Lock the host_lock before messing with these structures, since we
1368          * are running in a task context
1369          */
1370         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1371         list_del(&evt_struct->list);
1372         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1373         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1374 }
1375
1376 /**
1377  * ibmvscsi_get_host_config: Send the command to the server to get host
1378  * configuration data.  The data is opaque to us.
1379  */
1380 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1381                                    unsigned char *buffer, int length)
1382 {
1383         struct viosrp_host_config *host_config;
1384         struct srp_event_struct *evt_struct;
1385         unsigned long flags;
1386         dma_addr_t addr;
1387         int rc;
1388
1389         evt_struct = get_event_struct(&hostdata->pool);
1390         if (!evt_struct) {
1391                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1392                 return -1;
1393         }
1394
1395         init_event_struct(evt_struct,
1396                           sync_completion,
1397                           VIOSRP_MAD_FORMAT,
1398                           init_timeout);
1399
1400         host_config = &evt_struct->iu.mad.host_config;
1401
1402         /* Set up a lun reset SRP command */
1403         memset(host_config, 0x00, sizeof(*host_config));
1404         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1405         host_config->common.length = length;
1406         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1407                                                     length,
1408                                                     DMA_BIDIRECTIONAL);
1409
1410         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1411                 if (!firmware_has_feature(FW_FEATURE_CMO))
1412                         dev_err(hostdata->dev,
1413                                 "dma_mapping error getting host config\n");
1414                 free_event_struct(&hostdata->pool, evt_struct);
1415                 return -1;
1416         }
1417
1418         init_completion(&evt_struct->comp);
1419         spin_lock_irqsave(hostdata->host->host_lock, flags);
1420         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2);
1421         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1422         if (rc == 0)
1423                 wait_for_completion(&evt_struct->comp);
1424         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1425
1426         return rc;
1427 }
1428
1429 /**
1430  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1431  * @sdev:       struct scsi_device device to configure
1432  *
1433  * Enable allow_restart for a device if it is a disk.  Adjust the
1434  * queue_depth here also as is required by the documentation for
1435  * struct scsi_host_template.
1436  */
1437 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1438 {
1439         struct Scsi_Host *shost = sdev->host;
1440         unsigned long lock_flags = 0;
1441
1442         spin_lock_irqsave(shost->host_lock, lock_flags);
1443         if (sdev->type == TYPE_DISK) {
1444                 sdev->allow_restart = 1;
1445                 blk_queue_rq_timeout(sdev->request_queue, 60 * HZ);
1446         }
1447         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1448         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1449         return 0;
1450 }
1451
1452 /**
1453  * ibmvscsi_change_queue_depth - Change the device's queue depth
1454  * @sdev:       scsi device struct
1455  * @qdepth:     depth to set
1456  *
1457  * Return value:
1458  *      actual depth set
1459  **/
1460 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
1461 {
1462         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1463                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1464
1465         scsi_adjust_queue_depth(sdev, 0, qdepth);
1466         return sdev->queue_depth;
1467 }
1468
1469 /* ------------------------------------------------------------
1470  * sysfs attributes
1471  */
1472 static ssize_t show_host_srp_version(struct device *dev,
1473                                      struct device_attribute *attr, char *buf)
1474 {
1475         struct Scsi_Host *shost = class_to_shost(dev);
1476         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1477         int len;
1478
1479         len = snprintf(buf, PAGE_SIZE, "%s\n",
1480                        hostdata->madapter_info.srp_version);
1481         return len;
1482 }
1483
1484 static struct device_attribute ibmvscsi_host_srp_version = {
1485         .attr = {
1486                  .name = "srp_version",
1487                  .mode = S_IRUGO,
1488                  },
1489         .show = show_host_srp_version,
1490 };
1491
1492 static ssize_t show_host_partition_name(struct device *dev,
1493                                         struct device_attribute *attr,
1494                                         char *buf)
1495 {
1496         struct Scsi_Host *shost = class_to_shost(dev);
1497         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1498         int len;
1499
1500         len = snprintf(buf, PAGE_SIZE, "%s\n",
1501                        hostdata->madapter_info.partition_name);
1502         return len;
1503 }
1504
1505 static struct device_attribute ibmvscsi_host_partition_name = {
1506         .attr = {
1507                  .name = "partition_name",
1508                  .mode = S_IRUGO,
1509                  },
1510         .show = show_host_partition_name,
1511 };
1512
1513 static ssize_t show_host_partition_number(struct device *dev,
1514                                           struct device_attribute *attr,
1515                                           char *buf)
1516 {
1517         struct Scsi_Host *shost = class_to_shost(dev);
1518         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1519         int len;
1520
1521         len = snprintf(buf, PAGE_SIZE, "%d\n",
1522                        hostdata->madapter_info.partition_number);
1523         return len;
1524 }
1525
1526 static struct device_attribute ibmvscsi_host_partition_number = {
1527         .attr = {
1528                  .name = "partition_number",
1529                  .mode = S_IRUGO,
1530                  },
1531         .show = show_host_partition_number,
1532 };
1533
1534 static ssize_t show_host_mad_version(struct device *dev,
1535                                      struct device_attribute *attr, char *buf)
1536 {
1537         struct Scsi_Host *shost = class_to_shost(dev);
1538         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1539         int len;
1540
1541         len = snprintf(buf, PAGE_SIZE, "%d\n",
1542                        hostdata->madapter_info.mad_version);
1543         return len;
1544 }
1545
1546 static struct device_attribute ibmvscsi_host_mad_version = {
1547         .attr = {
1548                  .name = "mad_version",
1549                  .mode = S_IRUGO,
1550                  },
1551         .show = show_host_mad_version,
1552 };
1553
1554 static ssize_t show_host_os_type(struct device *dev,
1555                                  struct device_attribute *attr, char *buf)
1556 {
1557         struct Scsi_Host *shost = class_to_shost(dev);
1558         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1559         int len;
1560
1561         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1562         return len;
1563 }
1564
1565 static struct device_attribute ibmvscsi_host_os_type = {
1566         .attr = {
1567                  .name = "os_type",
1568                  .mode = S_IRUGO,
1569                  },
1570         .show = show_host_os_type,
1571 };
1572
1573 static ssize_t show_host_config(struct device *dev,
1574                                 struct device_attribute *attr, char *buf)
1575 {
1576         struct Scsi_Host *shost = class_to_shost(dev);
1577         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1578
1579         /* returns null-terminated host config data */
1580         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1581                 return strlen(buf);
1582         else
1583                 return 0;
1584 }
1585
1586 static struct device_attribute ibmvscsi_host_config = {
1587         .attr = {
1588                  .name = "config",
1589                  .mode = S_IRUGO,
1590                  },
1591         .show = show_host_config,
1592 };
1593
1594 static struct device_attribute *ibmvscsi_attrs[] = {
1595         &ibmvscsi_host_srp_version,
1596         &ibmvscsi_host_partition_name,
1597         &ibmvscsi_host_partition_number,
1598         &ibmvscsi_host_mad_version,
1599         &ibmvscsi_host_os_type,
1600         &ibmvscsi_host_config,
1601         NULL
1602 };
1603
1604 /* ------------------------------------------------------------
1605  * SCSI driver registration
1606  */
1607 static struct scsi_host_template driver_template = {
1608         .module = THIS_MODULE,
1609         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1610         .proc_name = "ibmvscsi",
1611         .queuecommand = ibmvscsi_queuecommand,
1612         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1613         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1614         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1615         .slave_configure = ibmvscsi_slave_configure,
1616         .change_queue_depth = ibmvscsi_change_queue_depth,
1617         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1618         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1619         .this_id = -1,
1620         .sg_tablesize = SG_ALL,
1621         .use_clustering = ENABLE_CLUSTERING,
1622         .shost_attrs = ibmvscsi_attrs,
1623 };
1624
1625 /**
1626  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1627  *
1628  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1629  *
1630  * Return value:
1631  *      Number of bytes of IO data the driver will need to perform well.
1632  */
1633 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1634 {
1635         /* iu_storage data allocated in initialize_event_pool */
1636         unsigned long desired_io = max_requests * sizeof(union viosrp_iu);
1637
1638         /* add io space for sg data */
1639         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1640                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1641
1642         return desired_io;
1643 }
1644
1645 /**
1646  * Called by bus code for each adapter
1647  */
1648 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1649 {
1650         struct ibmvscsi_host_data *hostdata;
1651         struct Scsi_Host *host;
1652         struct device *dev = &vdev->dev;
1653         struct srp_rport_identifiers ids;
1654         struct srp_rport *rport;
1655         unsigned long wait_switch = 0;
1656         int rc;
1657
1658         vdev->dev.driver_data = NULL;
1659
1660         driver_template.can_queue = max_requests;
1661         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1662         if (!host) {
1663                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1664                 goto scsi_host_alloc_failed;
1665         }
1666
1667         host->transportt = ibmvscsi_transport_template;
1668         hostdata = shost_priv(host);
1669         memset(hostdata, 0x00, sizeof(*hostdata));
1670         INIT_LIST_HEAD(&hostdata->sent);
1671         hostdata->host = host;
1672         hostdata->dev = dev;
1673         atomic_set(&hostdata->request_limit, -1);
1674         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1675
1676         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_requests);
1677         if (rc != 0 && rc != H_RESOURCE) {
1678                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1679                 goto init_crq_failed;
1680         }
1681         if (initialize_event_pool(&hostdata->pool, max_requests, hostdata) != 0) {
1682                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1683                 goto init_pool_failed;
1684         }
1685
1686         host->max_lun = 8;
1687         host->max_id = max_id;
1688         host->max_channel = max_channel;
1689
1690         if (scsi_add_host(hostdata->host, hostdata->dev))
1691                 goto add_host_failed;
1692
1693         /* we don't have a proper target_port_id so let's use the fake one */
1694         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1695                sizeof(ids.port_id));
1696         ids.roles = SRP_RPORT_ROLE_TARGET;
1697         rport = srp_rport_add(host, &ids);
1698         if (IS_ERR(rport))
1699                 goto add_srp_port_failed;
1700
1701         /* Try to send an initialization message.  Note that this is allowed
1702          * to fail if the other end is not acive.  In that case we don't
1703          * want to scan
1704          */
1705         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1706             || rc == H_RESOURCE) {
1707                 /*
1708                  * Wait around max init_timeout secs for the adapter to finish
1709                  * initializing. When we are done initializing, we will have a
1710                  * valid request_limit.  We don't want Linux scanning before
1711                  * we are ready.
1712                  */
1713                 for (wait_switch = jiffies + (init_timeout * HZ);
1714                      time_before(jiffies, wait_switch) &&
1715                      atomic_read(&hostdata->request_limit) < 2;) {
1716
1717                         msleep(10);
1718                 }
1719
1720                 /* if we now have a valid request_limit, initiate a scan */
1721                 if (atomic_read(&hostdata->request_limit) > 0)
1722                         scsi_scan_host(host);
1723         }
1724
1725         vdev->dev.driver_data = hostdata;
1726         return 0;
1727
1728       add_srp_port_failed:
1729         scsi_remove_host(hostdata->host);
1730       add_host_failed:
1731         release_event_pool(&hostdata->pool, hostdata);
1732       init_pool_failed:
1733         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_requests);
1734       init_crq_failed:
1735         scsi_host_put(host);
1736       scsi_host_alloc_failed:
1737         return -1;
1738 }
1739
1740 static int ibmvscsi_remove(struct vio_dev *vdev)
1741 {
1742         struct ibmvscsi_host_data *hostdata = vdev->dev.driver_data;
1743         release_event_pool(&hostdata->pool, hostdata);
1744         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
1745                                         max_requests);
1746
1747         srp_remove_host(hostdata->host);
1748         scsi_remove_host(hostdata->host);
1749         scsi_host_put(hostdata->host);
1750
1751         return 0;
1752 }
1753
1754 /**
1755  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
1756  * support.
1757  */
1758 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1759         {"vscsi", "IBM,v-scsi"},
1760         { "", "" }
1761 };
1762 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1763
1764 static struct vio_driver ibmvscsi_driver = {
1765         .id_table = ibmvscsi_device_table,
1766         .probe = ibmvscsi_probe,
1767         .remove = ibmvscsi_remove,
1768         .get_desired_dma = ibmvscsi_get_desired_dma,
1769         .driver = {
1770                 .name = "ibmvscsi",
1771                 .owner = THIS_MODULE,
1772         }
1773 };
1774
1775 static struct srp_function_template ibmvscsi_transport_functions = {
1776 };
1777
1778 int __init ibmvscsi_module_init(void)
1779 {
1780         int ret;
1781
1782         if (firmware_has_feature(FW_FEATURE_ISERIES))
1783                 ibmvscsi_ops = &iseriesvscsi_ops;
1784         else if (firmware_has_feature(FW_FEATURE_VIO))
1785                 ibmvscsi_ops = &rpavscsi_ops;
1786         else
1787                 return -ENODEV;
1788
1789         ibmvscsi_transport_template =
1790                 srp_attach_transport(&ibmvscsi_transport_functions);
1791         if (!ibmvscsi_transport_template)
1792                 return -ENOMEM;
1793
1794         ret = vio_register_driver(&ibmvscsi_driver);
1795         if (ret)
1796                 srp_release_transport(ibmvscsi_transport_template);
1797         return ret;
1798 }
1799
1800 void __exit ibmvscsi_module_exit(void)
1801 {
1802         vio_unregister_driver(&ibmvscsi_driver);
1803         srp_release_transport(ibmvscsi_transport_template);
1804 }
1805
1806 module_init(ibmvscsi_module_init);
1807 module_exit(ibmvscsi_module_exit);