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   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 <linux/of.h>
  74 #include <asm/firmware.h>
  75 #include <asm/vio.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 = 300;
  91 static int login_timeout = 60;
  92 static int info_timeout = 30;
  93 static int abort_timeout = 60;
  94 static int reset_timeout = 60;
  95 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
  96 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
  97 static int fast_fail = 1;
  98 static int client_reserve = 1;
  99
 100 static struct scsi_transport_template *ibmvscsi_transport_template;
 101
 102 #define IBMVSCSI_VERSION "1.5.8"
 103
 104 static struct ibmvscsi_ops *ibmvscsi_ops;
 105
 106 MODULE_DESCRIPTION("IBM Virtual SCSI");
 107 MODULE_AUTHOR("Dave Boutcher");
 108 MODULE_LICENSE("GPL");
 109 MODULE_VERSION(IBMVSCSI_VERSION);
 110
 111 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
 112 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
 113 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
 114 MODULE_PARM_DESC(max_channel, "Largest channel value");
 115 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
 116 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
 117 module_param_named(max_requests, max_requests, int, S_IRUGO);
 118 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
 119 module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR);
 120 MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]");
 121 module_param_named(client_reserve, client_reserve, int, S_IRUGO );
 122 MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release");
 123
 124 /* ------------------------------------------------------------
 125  * Routines for the event pool and event structs
 126  */
 127 /**
 128  * initialize_event_pool: - Allocates and initializes the event pool for a host
 129  * @pool:       event_pool to be initialized
 130  * @size:       Number of events in pool
 131  * @hostdata:   ibmvscsi_host_data who owns the event pool
 132  *
 133  * Returns zero on success.
 134 */
 135 static int initialize_event_pool(struct event_pool *pool,
 136                                  int size, struct ibmvscsi_host_data *hostdata)
 137 {
 138         int i;
 139
 140         pool->size = size;
 141         pool->next = 0;
 142         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
 143         if (!pool->events)
 144                 return -ENOMEM;
 145
 146         pool->iu_storage =
 147             dma_alloc_coherent(hostdata->dev,
 148                                pool->size * sizeof(*pool->iu_storage),
 149                                &pool->iu_token, 0);
 150         if (!pool->iu_storage) {
 151                 kfree(pool->events);
 152                 return -ENOMEM;
 153         }
 154
 155         for (i = 0; i < pool->size; ++i) {
 156                 struct srp_event_struct *evt = &pool->events[i];
 157                 memset(&evt->crq, 0x00, sizeof(evt->crq));
 158                 atomic_set(&evt->free, 1);
 159                 evt->crq.valid = 0x80;
 160                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
 161                 evt->crq.IU_data_ptr = pool->iu_token +
 162                         sizeof(*evt->xfer_iu) * i;
 163                 evt->xfer_iu = pool->iu_storage + i;
 164                 evt->hostdata = hostdata;
 165                 evt->ext_list = NULL;
 166                 evt->ext_list_token = 0;
 167         }
 168
 169         return 0;
 170 }
 171
 172 /**
 173  * release_event_pool: - Frees memory of an event pool of a host
 174  * @pool:       event_pool to be released
 175  * @hostdata:   ibmvscsi_host_data who owns the even pool
 176  *
 177  * Returns zero on success.
 178 */
 179 static void release_event_pool(struct event_pool *pool,
 180                                struct ibmvscsi_host_data *hostdata)
 181 {
 182         int i, in_use = 0;
 183         for (i = 0; i < pool->size; ++i) {
 184                 if (atomic_read(&pool->events[i].free) != 1)
 185                         ++in_use;
 186                 if (pool->events[i].ext_list) {
 187                         dma_free_coherent(hostdata->dev,
 188                                   SG_ALL * sizeof(struct srp_direct_buf),
 189                                   pool->events[i].ext_list,
 190                                   pool->events[i].ext_list_token);
 191                 }
 192         }
 193         if (in_use)
 194                 dev_warn(hostdata->dev, "releasing event pool with %d "
 195                          "events still in use?\n", in_use);
 196         kfree(pool->events);
 197         dma_free_coherent(hostdata->dev,
 198                           pool->size * sizeof(*pool->iu_storage),
 199                           pool->iu_storage, pool->iu_token);
 200 }
 201
 202 /**
 203  * valid_event_struct: - Determines if event is valid.
 204  * @pool:       event_pool that contains the event
 205  * @evt:        srp_event_struct to be checked for validity
 206  *
 207  * Returns zero if event is invalid, one otherwise.
 208 */
 209 static int valid_event_struct(struct event_pool *pool,
 210                                 struct srp_event_struct *evt)
 211 {
 212         int index = evt - pool->events;
 213         if (index < 0 || index >= pool->size)   /* outside of bounds */
 214                 return 0;
 215         if (evt != pool->events + index)        /* unaligned */
 216                 return 0;
 217         return 1;
 218 }
 219
 220 /**
 221  * ibmvscsi_free-event_struct: - Changes status of event to "free"
 222  * @pool:       event_pool that contains the event
 223  * @evt:        srp_event_struct to be modified
 224  *
 225 */
 226 static void free_event_struct(struct event_pool *pool,
 227                                        struct srp_event_struct *evt)
 228 {
 229         if (!valid_event_struct(pool, evt)) {
 230                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
 231                         "(not in pool %p)\n", evt, pool->events);
 232                 return;
 233         }
 234         if (atomic_inc_return(&evt->free) != 1) {
 235                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
 236                         "which is not in use!\n", evt);
 237                 return;
 238         }
 239 }
 240
 241 /**
 242  * get_evt_struct: - Gets the next free event in pool
 243  * @pool:       event_pool that contains the events to be searched
 244  *
 245  * Returns the next event in "free" state, and NULL if none are free.
 246  * Note that no synchronization is done here, we assume the host_lock
 247  * will syncrhonze things.
 248 */
 249 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
 250 {
 251         int i;
 252         int poolsize = pool->size;
 253         int offset = pool->next;
 254
 255         for (i = 0; i < poolsize; i++) {
 256                 offset = (offset + 1) % poolsize;
 257                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
 258                         pool->next = offset;
 259                         return &pool->events[offset];
 260                 }
 261         }
 262
 263         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
 264         return NULL;
 265 }
 266
 267 /**
 268  * init_event_struct: Initialize fields in an event struct that are always
 269  *                    required.
 270  * @evt:        The event
 271  * @done:       Routine to call when the event is responded to
 272  * @format:     SRP or MAD format
 273  * @timeout:    timeout value set in the CRQ
 274  */
 275 static void init_event_struct(struct srp_event_struct *evt_struct,
 276                               void (*done) (struct srp_event_struct *),
 277                               u8 format,
 278                               int timeout)
 279 {
 280         evt_struct->cmnd = NULL;
 281         evt_struct->cmnd_done = NULL;
 282         evt_struct->sync_srp = NULL;
 283         evt_struct->crq.format = format;
 284         evt_struct->crq.timeout = timeout;
 285         evt_struct->done = done;
 286 }
 287
 288 /* ------------------------------------------------------------
 289  * Routines for receiving SCSI responses from the hosting partition
 290  */
 291
 292 /**
 293  * set_srp_direction: Set the fields in the srp related to data
 294  *     direction and number of buffers based on the direction in
 295  *     the scsi_cmnd and the number of buffers
 296  */
 297 static void set_srp_direction(struct scsi_cmnd *cmd,
 298                               struct srp_cmd *srp_cmd,
 299                               int numbuf)
 300 {
 301         u8 fmt;
 302
 303         if (numbuf == 0)
 304                 return;
 305
 306         if (numbuf == 1)
 307                 fmt = SRP_DATA_DESC_DIRECT;
 308         else {
 309                 fmt = SRP_DATA_DESC_INDIRECT;
 310                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
 311
 312                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
 313                         srp_cmd->data_out_desc_cnt = numbuf;
 314                 else
 315                         srp_cmd->data_in_desc_cnt = numbuf;
 316         }
 317
 318         if (cmd->sc_data_direction == DMA_TO_DEVICE)
 319                 srp_cmd->buf_fmt = fmt << 4;
 320         else
 321                 srp_cmd->buf_fmt = fmt;
 322 }
 323
 324 static void unmap_sg_list(int num_entries,
 325                 struct device *dev,
 326                 struct srp_direct_buf *md)
 327 {
 328         int i;
 329
 330         for (i = 0; i < num_entries; ++i)
 331                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
 332 }
 333
 334 /**
 335  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
 336  * @cmd:        srp_cmd whose additional_data member will be unmapped
 337  * @dev:        device for which the memory is mapped
 338  *
 339 */
 340 static void unmap_cmd_data(struct srp_cmd *cmd,
 341                            struct srp_event_struct *evt_struct,
 342                            struct device *dev)
 343 {
 344         u8 out_fmt, in_fmt;
 345
 346         out_fmt = cmd->buf_fmt >> 4;
 347         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
 348
 349         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
 350                 return;
 351         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
 352                  in_fmt == SRP_DATA_DESC_DIRECT) {
 353                 struct srp_direct_buf *data =
 354                         (struct srp_direct_buf *) cmd->add_data;
 355                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
 356         } else {
 357                 struct srp_indirect_buf *indirect =
 358                         (struct srp_indirect_buf *) cmd->add_data;
 359                 int num_mapped = indirect->table_desc.len /
 360                         sizeof(struct srp_direct_buf);
 361
 362                 if (num_mapped <= MAX_INDIRECT_BUFS) {
 363                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
 364                         return;
 365                 }
 366
 367                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
 368         }
 369 }
 370
 371 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
 372                        struct srp_direct_buf *md)
 373 {
 374         int i;
 375         struct scatterlist *sg;
 376         u64 total_length = 0;
 377
 378         scsi_for_each_sg(cmd, sg, nseg, i) {
 379                 struct srp_direct_buf *descr = md + i;
 380                 descr->va = sg_dma_address(sg);
 381                 descr->len = sg_dma_len(sg);
 382                 descr->key = 0;
 383                 total_length += sg_dma_len(sg);
 384         }
 385         return total_length;
 386 }
 387
 388 /**
 389  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
 390  * @cmd:        Scsi_Cmnd with the scatterlist
 391  * @srp_cmd:    srp_cmd that contains the memory descriptor
 392  * @dev:        device for which to map dma memory
 393  *
 394  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 395  * Returns 1 on success.
 396 */
 397 static int map_sg_data(struct scsi_cmnd *cmd,
 398                        struct srp_event_struct *evt_struct,
 399                        struct srp_cmd *srp_cmd, struct device *dev)
 400 {
 401
 402         int sg_mapped;
 403         u64 total_length = 0;
 404         struct srp_direct_buf *data =
 405                 (struct srp_direct_buf *) srp_cmd->add_data;
 406         struct srp_indirect_buf *indirect =
 407                 (struct srp_indirect_buf *) data;
 408
 409         sg_mapped = scsi_dma_map(cmd);
 410         if (!sg_mapped)
 411                 return 1;
 412         else if (sg_mapped < 0)
 413                 return 0;
 414
 415         set_srp_direction(cmd, srp_cmd, sg_mapped);
 416
 417         /* special case; we can use a single direct descriptor */
 418         if (sg_mapped == 1) {
 419                 map_sg_list(cmd, sg_mapped, data);
 420                 return 1;
 421         }
 422
 423         indirect->table_desc.va = 0;
 424         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
 425         indirect->table_desc.key = 0;
 426
 427         if (sg_mapped <= MAX_INDIRECT_BUFS) {
 428                 total_length = map_sg_list(cmd, sg_mapped,
 429                                            &indirect->desc_list[0]);
 430                 indirect->len = total_length;
 431                 return 1;
 432         }
 433
 434         /* get indirect table */
 435         if (!evt_struct->ext_list) {
 436                 evt_struct->ext_list = (struct srp_direct_buf *)
 437                         dma_alloc_coherent(dev,
 438                                            SG_ALL * sizeof(struct srp_direct_buf),
 439                                            &evt_struct->ext_list_token, 0);
 440                 if (!evt_struct->ext_list) {
 441                         if (!firmware_has_feature(FW_FEATURE_CMO))
 442                                 sdev_printk(KERN_ERR, cmd->device,
 443                                             "Can't allocate memory "
 444                                             "for indirect table\n");
 445                         scsi_dma_unmap(cmd);
 446                         return 0;
 447                 }
 448         }
 449
 450         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
 451
 452         indirect->len = total_length;
 453         indirect->table_desc.va = evt_struct->ext_list_token;
 454         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
 455         memcpy(indirect->desc_list, evt_struct->ext_list,
 456                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
 457         return 1;
 458 }
 459
 460 /**
 461  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
 462  * @cmd:        struct scsi_cmnd with the memory to be mapped
 463  * @srp_cmd:    srp_cmd that contains the memory descriptor
 464  * @dev:        dma device for which to map dma memory
 465  *
 466  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
 467  * Returns 1 on success.
 468 */
 469 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
 470                                 struct srp_event_struct *evt_struct,
 471                                 struct srp_cmd *srp_cmd, struct device *dev)
 472 {
 473         switch (cmd->sc_data_direction) {
 474         case DMA_FROM_DEVICE:
 475         case DMA_TO_DEVICE:
 476                 break;
 477         case DMA_NONE:
 478                 return 1;
 479         case DMA_BIDIRECTIONAL:
 480                 sdev_printk(KERN_ERR, cmd->device,
 481                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
 482                 return 0;
 483         default:
 484                 sdev_printk(KERN_ERR, cmd->device,
 485                             "Unknown data direction 0x%02x; can't map!\n",
 486                             cmd->sc_data_direction);
 487                 return 0;
 488         }
 489
 490         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
 491 }
 492
 493 /**
 494  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
 495  * @hostdata:    the adapter
 496  */
 497 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
 498 {
 499         struct srp_event_struct *tmp_evt, *pos;
 500         unsigned long flags;
 501
 502         spin_lock_irqsave(hostdata->host->host_lock, flags);
 503         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
 504                 list_del(&tmp_evt->list);
 505                 del_timer(&tmp_evt->timer);
 506                 if (tmp_evt->cmnd) {
 507                         tmp_evt->cmnd->result = (error_code << 16);
 508                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
 509                                        tmp_evt,
 510                                        tmp_evt->hostdata->dev);
 511                         if (tmp_evt->cmnd_done)
 512                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
 513                 } else if (tmp_evt->done)
 514                         tmp_evt->done(tmp_evt);
 515                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
 516         }
 517         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 518 }
 519
 520 /**
 521  * ibmvscsi_reset_host - Reset the connection to the server
 522  * @hostdata:   struct ibmvscsi_host_data to reset
 523 */
 524 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
 525 {
 526         scsi_block_requests(hostdata->host);
 527         atomic_set(&hostdata->request_limit, 0);
 528
 529         purge_requests(hostdata, DID_ERROR);
 530         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata)) ||
 531             (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0)) ||
 532             (vio_enable_interrupts(to_vio_dev(hostdata->dev)))) {
 533                 atomic_set(&hostdata->request_limit, -1);
 534                 dev_err(hostdata->dev, "error after reset\n");
 535         }
 536
 537         scsi_unblock_requests(hostdata->host);
 538 }
 539
 540 /**
 541  * ibmvscsi_timeout - Internal command timeout handler
 542  * @evt_struct: struct srp_event_struct that timed out
 543  *
 544  * Called when an internally generated command times out
 545 */
 546 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
 547 {
 548         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 549
 550         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
 551                 evt_struct->iu.srp.cmd.opcode);
 552
 553         ibmvscsi_reset_host(hostdata);
 554 }
 555
 556
 557 /* ------------------------------------------------------------
 558  * Routines for sending and receiving SRPs
 559  */
 560 /**
 561  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 562  * @evt_struct: evt_struct to be sent
 563  * @hostdata:   ibmvscsi_host_data of host
 564  * @timeout:    timeout in seconds - 0 means do not time command
 565  *
 566  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 567  * Note that this routine assumes that host_lock is held for synchronization
 568 */
 569 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 570                                    struct ibmvscsi_host_data *hostdata,
 571                                    unsigned long timeout)
 572 {
 573         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 574         int request_status = 0;
 575         int rc;
 576
 577         /* If we have exhausted our request limit, just fail this request,
 578          * unless it is for a reset or abort.
 579          * Note that there are rare cases involving driver generated requests
 580          * (such as task management requests) that the mid layer may think we
 581          * can handle more requests (can_queue) when we actually can't
 582          */
 583         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
 584                 request_status =
 585                         atomic_dec_if_positive(&hostdata->request_limit);
 586                 /* If request limit was -1 when we started, it is now even
 587                  * less than that
 588                  */
 589                 if (request_status < -1)
 590                         goto send_error;
 591                 /* Otherwise, we may have run out of requests. */
 592                 /* If request limit was 0 when we started the adapter is in the
 593                  * process of performing a login with the server adapter, or
 594                  * we may have run out of requests.
 595                  */
 596                 else if (request_status == -1 &&
 597                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
 598                         goto send_busy;
 599                 /* Abort and reset calls should make it through.
 600                  * Nothing except abort and reset should use the last two
 601                  * slots unless we had two or less to begin with.
 602                  */
 603                 else if (request_status < 2 &&
 604                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
 605                         /* In the case that we have less than two requests
 606                          * available, check the server limit as a combination
 607                          * of the request limit and the number of requests
 608                          * in-flight (the size of the send list).  If the
 609                          * server limit is greater than 2, return busy so
 610                          * that the last two are reserved for reset and abort.
 611                          */
 612                         int server_limit = request_status;
 613                         struct srp_event_struct *tmp_evt;
 614
 615                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 616                                 server_limit++;
 617                         }
 618
 619                         if (server_limit > 2)
 620                                 goto send_busy;
 621                 }
 622         }
 623
 624         /* Copy the IU into the transfer area */
 625         *evt_struct->xfer_iu = evt_struct->iu;
 626         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 627
 628         /* Add this to the sent list.  We need to do this
 629          * before we actually send
 630          * in case it comes back REALLY fast
 631          */
 632         list_add_tail(&evt_struct->list, &hostdata->sent);
 633
 634         init_timer(&evt_struct->timer);
 635         if (timeout) {
 636                 evt_struct->timer.data = (unsigned long) evt_struct;
 637                 evt_struct->timer.expires = jiffies + (timeout * HZ);
 638                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
 639                 add_timer(&evt_struct->timer);
 640         }
 641
 642         if ((rc =
 643              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 644                 list_del(&evt_struct->list);
 645                 del_timer(&evt_struct->timer);
 646
 647                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
 648                  * Firmware will send a CRQ with a transport event (0xFF) to
 649                  * tell this client what has happened to the transport.  This
 650                  * will be handled in ibmvscsi_handle_crq()
 651                  */
 652                 if (rc == H_CLOSED) {
 653                         dev_warn(hostdata->dev, "send warning. "
 654                                  "Receive queue closed, will retry.\n");
 655                         goto send_busy;
 656                 }
 657                 dev_err(hostdata->dev, "send error %d\n", rc);
 658                 atomic_inc(&hostdata->request_limit);
 659                 goto send_error;
 660         }
 661
 662         return 0;
 663
 664  send_busy:
 665         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 666
 667         free_event_struct(&hostdata->pool, evt_struct);
 668         if (request_status != -1)
 669                 atomic_inc(&hostdata->request_limit);
 670         return SCSI_MLQUEUE_HOST_BUSY;
 671
 672  send_error:
 673         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 674
 675         if (evt_struct->cmnd != NULL) {
 676                 evt_struct->cmnd->result = DID_ERROR << 16;
 677                 evt_struct->cmnd_done(evt_struct->cmnd);
 678         } else if (evt_struct->done)
 679                 evt_struct->done(evt_struct);
 680
 681         free_event_struct(&hostdata->pool, evt_struct);
 682         return 0;
 683 }
 684
 685 /**
 686  * handle_cmd_rsp: -  Handle responses from commands
 687  * @evt_struct: srp_event_struct to be handled
 688  *
 689  * Used as a callback by when sending scsi cmds.
 690  * Gets called by ibmvscsi_handle_crq()
 691 */
 692 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 693 {
 694         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 695         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 696
 697         if (unlikely(rsp->opcode != SRP_RSP)) {
 698                 if (printk_ratelimit())
 699                         dev_warn(evt_struct->hostdata->dev,
 700                                  "bad SRP RSP type %d\n", rsp->opcode);
 701         }
 702
 703         if (cmnd) {
 704                 cmnd->result |= rsp->status;
 705                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 706                         memcpy(cmnd->sense_buffer,
 707                                rsp->data,
 708                                rsp->sense_data_len);
 709                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 710                                evt_struct,
 711                                evt_struct->hostdata->dev);
 712
 713                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 714                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
 715                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 716                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
 717         }
 718
 719         if (evt_struct->cmnd_done)
 720                 evt_struct->cmnd_done(cmnd);
 721 }
 722
 723 /**
 724  * lun_from_dev: - Returns the lun of the scsi device
 725  * @dev:        struct scsi_device
 726  *
 727 */
 728 static inline u16 lun_from_dev(struct scsi_device *dev)
 729 {
 730         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 731 }
 732
 733 /**
 734  * ibmvscsi_queue: - The queuecommand function of the scsi template
 735  * @cmd:        struct scsi_cmnd to be executed
 736  * @done:       Callback function to be called when cmd is completed
 737 */
 738 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
 739                                  void (*done) (struct scsi_cmnd *))
 740 {
 741         struct srp_cmd *srp_cmd;
 742         struct srp_event_struct *evt_struct;
 743         struct srp_indirect_buf *indirect;
 744         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
 745         u16 lun = lun_from_dev(cmnd->device);
 746         u8 out_fmt, in_fmt;
 747
 748         cmnd->result = (DID_OK << 16);
 749         evt_struct = get_event_struct(&hostdata->pool);
 750         if (!evt_struct)
 751                 return SCSI_MLQUEUE_HOST_BUSY;
 752
 753         /* Set up the actual SRP IU */
 754         srp_cmd = &evt_struct->iu.srp.cmd;
 755         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 756         srp_cmd->opcode = SRP_CMD;
 757         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
 758         srp_cmd->lun = ((u64) lun) << 48;
 759
 760         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 761                 if (!firmware_has_feature(FW_FEATURE_CMO))
 762                         sdev_printk(KERN_ERR, cmnd->device,
 763                                     "couldn't convert cmd to srp_cmd\n");
 764                 free_event_struct(&hostdata->pool, evt_struct);
 765                 return SCSI_MLQUEUE_HOST_BUSY;
 766         }
 767
 768         init_event_struct(evt_struct,
 769                           handle_cmd_rsp,
 770                           VIOSRP_SRP_FORMAT,
 771                           cmnd->request->timeout/HZ);
 772
 773         evt_struct->cmnd = cmnd;
 774         evt_struct->cmnd_done = done;
 775
 776         /* Fix up dma address of the buffer itself */
 777         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 778         out_fmt = srp_cmd->buf_fmt >> 4;
 779         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 780         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 781              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 782             indirect->table_desc.va == 0) {
 783                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 784                         offsetof(struct srp_cmd, add_data) +
 785                         offsetof(struct srp_indirect_buf, desc_list);
 786         }
 787
 788         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
 789 }
 790
 791 /* ------------------------------------------------------------
 792  * Routines for driver initialization
 793  */
 794
 795 /**
 796  * map_persist_bufs: - Pre-map persistent data for adapter logins
 797  * @hostdata:   ibmvscsi_host_data of host
 798  *
 799  * Map the capabilities and adapter info DMA buffers to avoid runtime failures.
 800  * Return 1 on error, 0 on success.
 801  */
 802 static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
 803 {
 804
 805         hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
 806                                              sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 807
 808         if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
 809                 dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
 810                 return 1;
 811         }
 812
 813         hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
 814                                                      &hostdata->madapter_info,
 815                                                      sizeof(hostdata->madapter_info),
 816                                                      DMA_BIDIRECTIONAL);
 817         if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
 818                 dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
 819                 dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 820                                  sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 821                 return 1;
 822         }
 823
 824         return 0;
 825 }
 826
 827 /**
 828  * unmap_persist_bufs: - Unmap persistent data needed for adapter logins
 829  * @hostdata:   ibmvscsi_host_data of host
 830  *
 831  * Unmap the capabilities and adapter info DMA buffers
 832  */
 833 static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
 834 {
 835         dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 836                          sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 837
 838         dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
 839                          sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
 840 }
 841
 842 /**
 843  * login_rsp: - Handle response to SRP login request
 844  * @evt_struct: srp_event_struct with the response
 845  *
 846  * Used as a "done" callback by when sending srp_login. Gets called
 847  * by ibmvscsi_handle_crq()
 848 */
 849 static void login_rsp(struct srp_event_struct *evt_struct)
 850 {
 851         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 852         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 853         case SRP_LOGIN_RSP:     /* it worked! */
 854                 break;
 855         case SRP_LOGIN_REJ:     /* refused! */
 856                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
 857                          evt_struct->xfer_iu->srp.login_rej.reason);
 858                 /* Login failed.  */
 859                 atomic_set(&hostdata->request_limit, -1);
 860                 return;
 861         default:
 862                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
 863                         evt_struct->xfer_iu->srp.login_rsp.opcode);
 864                 /* Login failed.  */
 865                 atomic_set(&hostdata->request_limit, -1);
 866                 return;
 867         }
 868
 869         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
 870         hostdata->client_migrated = 0;
 871
 872         /* Now we know what the real request-limit is.
 873          * This value is set rather than added to request_limit because
 874          * request_limit could have been set to -1 by this client.
 875          */
 876         atomic_set(&hostdata->request_limit,
 877                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 878
 879         /* If we had any pending I/Os, kick them */
 880         scsi_unblock_requests(hostdata->host);
 881 }
 882
 883 /**
 884  * send_srp_login: - Sends the srp login
 885  * @hostdata:   ibmvscsi_host_data of host
 886  *
 887  * Returns zero if successful.
 888 */
 889 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 890 {
 891         int rc;
 892         unsigned long flags;
 893         struct srp_login_req *login;
 894         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 895
 896         BUG_ON(!evt_struct);
 897         init_event_struct(evt_struct, login_rsp,
 898                           VIOSRP_SRP_FORMAT, login_timeout);
 899
 900         login = &evt_struct->iu.srp.login_req;
 901         memset(login, 0, sizeof(*login));
 902         login->opcode = SRP_LOGIN_REQ;
 903         login->req_it_iu_len = sizeof(union srp_iu);
 904         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 905
 906         spin_lock_irqsave(hostdata->host->host_lock, flags);
 907         /* Start out with a request limit of 0, since this is negotiated in
 908          * the login request we are just sending and login requests always
 909          * get sent by the driver regardless of request_limit.
 910          */
 911         atomic_set(&hostdata->request_limit, 0);
 912
 913         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
 914         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 915         dev_info(hostdata->dev, "sent SRP login\n");
 916         return rc;
 917 };
 918
 919 /**
 920  * capabilities_rsp: - Handle response to MAD adapter capabilities request
 921  * @evt_struct: srp_event_struct with the response
 922  *
 923  * Used as a "done" callback by when sending adapter_info.
 924  */
 925 static void capabilities_rsp(struct srp_event_struct *evt_struct)
 926 {
 927         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 928
 929         if (evt_struct->xfer_iu->mad.capabilities.common.status) {
 930                 dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
 931                         evt_struct->xfer_iu->mad.capabilities.common.status);
 932         } else {
 933                 if (hostdata->caps.migration.common.server_support != SERVER_SUPPORTS_CAP)
 934                         dev_info(hostdata->dev, "Partition migration not supported\n");
 935
 936                 if (client_reserve) {
 937                         if (hostdata->caps.reserve.common.server_support ==
 938                             SERVER_SUPPORTS_CAP)
 939                                 dev_info(hostdata->dev, "Client reserve enabled\n");
 940                         else
 941                                 dev_info(hostdata->dev, "Client reserve not supported\n");
 942                 }
 943         }
 944
 945         send_srp_login(hostdata);
 946 }
 947
 948 /**
 949  * send_mad_capabilities: - Sends the mad capabilities request
 950  *      and stores the result so it can be retrieved with
 951  * @hostdata:   ibmvscsi_host_data of host
 952  */
 953 static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
 954 {
 955         struct viosrp_capabilities *req;
 956         struct srp_event_struct *evt_struct;
 957         unsigned long flags;
 958         struct device_node *of_node = hostdata->dev->archdata.of_node;
 959         const char *location;
 960
 961         evt_struct = get_event_struct(&hostdata->pool);
 962         BUG_ON(!evt_struct);
 963
 964         init_event_struct(evt_struct, capabilities_rsp,
 965                           VIOSRP_MAD_FORMAT, info_timeout);
 966
 967         req = &evt_struct->iu.mad.capabilities;
 968         memset(req, 0, sizeof(*req));
 969
 970         hostdata->caps.flags = CAP_LIST_SUPPORTED;
 971         if (hostdata->client_migrated)
 972                 hostdata->caps.flags |= CLIENT_MIGRATED;
 973
 974         strncpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
 975                 sizeof(hostdata->caps.name));
 976         hostdata->caps.name[sizeof(hostdata->caps.name) - 1] = '\0';
 977
 978         location = of_get_property(of_node, "ibm,loc-code", NULL);
 979         location = location ? location : dev_name(hostdata->dev);
 980         strncpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
 981         hostdata->caps.loc[sizeof(hostdata->caps.loc) - 1] = '\0';
 982
 983         req->common.type = VIOSRP_CAPABILITIES_TYPE;
 984         req->buffer = hostdata->caps_addr;
 985
 986         hostdata->caps.migration.common.cap_type = MIGRATION_CAPABILITIES;
 987         hostdata->caps.migration.common.length = sizeof(hostdata->caps.migration);
 988         hostdata->caps.migration.common.server_support = SERVER_SUPPORTS_CAP;
 989         hostdata->caps.migration.ecl = 1;
 990
 991         if (client_reserve) {
 992                 hostdata->caps.reserve.common.cap_type = RESERVATION_CAPABILITIES;
 993                 hostdata->caps.reserve.common.length = sizeof(hostdata->caps.reserve);
 994                 hostdata->caps.reserve.common.server_support = SERVER_SUPPORTS_CAP;
 995                 hostdata->caps.reserve.type = CLIENT_RESERVE_SCSI_2;
 996                 req->common.length = sizeof(hostdata->caps);
 997         } else
 998                 req->common.length = sizeof(hostdata->caps) - sizeof(hostdata->caps.reserve);
 999
1000         spin_lock_irqsave(hostdata->host->host_lock, flags);
1001         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1002                 dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
1003         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1004 };
1005
1006 /**
1007  * fast_fail_rsp: - Handle response to MAD enable fast fail
1008  * @evt_struct: srp_event_struct with the response
1009  *
1010  * Used as a "done" callback by when sending enable fast fail. Gets called
1011  * by ibmvscsi_handle_crq()
1012  */
1013 static void fast_fail_rsp(struct srp_event_struct *evt_struct)
1014 {
1015         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1016         u8 status = evt_struct->xfer_iu->mad.fast_fail.common.status;
1017
1018         if (status == VIOSRP_MAD_NOT_SUPPORTED)
1019                 dev_err(hostdata->dev, "fast_fail not supported in server\n");
1020         else if (status == VIOSRP_MAD_FAILED)
1021                 dev_err(hostdata->dev, "fast_fail request failed\n");
1022         else if (status != VIOSRP_MAD_SUCCESS)
1023                 dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
1024
1025         send_mad_capabilities(hostdata);
1026 }
1027
1028 /**
1029  * init_host - Start host initialization
1030  * @hostdata:   ibmvscsi_host_data of host
1031  *
1032  * Returns zero if successful.
1033  */
1034 static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
1035 {
1036         int rc;
1037         unsigned long flags;
1038         struct viosrp_fast_fail *fast_fail_mad;
1039         struct srp_event_struct *evt_struct;
1040
1041         if (!fast_fail) {
1042                 send_mad_capabilities(hostdata);
1043                 return 0;
1044         }
1045
1046         evt_struct = get_event_struct(&hostdata->pool);
1047         BUG_ON(!evt_struct);
1048
1049         init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
1050
1051         fast_fail_mad = &evt_struct->iu.mad.fast_fail;
1052         memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
1053         fast_fail_mad->common.type = VIOSRP_ENABLE_FAST_FAIL;
1054         fast_fail_mad->common.length = sizeof(*fast_fail_mad);
1055
1056         spin_lock_irqsave(hostdata->host->host_lock, flags);
1057         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1058         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1059         return rc;
1060 }
1061
1062 /**
1063  * adapter_info_rsp: - Handle response to MAD adapter info request
1064  * @evt_struct: srp_event_struct with the response
1065  *
1066  * Used as a "done" callback by when sending adapter_info. Gets called
1067  * by ibmvscsi_handle_crq()
1068 */
1069 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
1070 {
1071         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1072
1073         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
1074                 dev_err(hostdata->dev, "error %d getting adapter info\n",
1075                         evt_struct->xfer_iu->mad.adapter_info.common.status);
1076         } else {
1077                 dev_info(hostdata->dev, "host srp version: %s, "
1078                          "host partition %s (%d), OS %d, max io %u\n",
1079                          hostdata->madapter_info.srp_version,
1080                          hostdata->madapter_info.partition_name,
1081                          hostdata->madapter_info.partition_number,
1082                          hostdata->madapter_info.os_type,
1083                          hostdata->madapter_info.port_max_txu[0]);
1084
1085                 if (hostdata->madapter_info.port_max_txu[0])
1086                         hostdata->host->max_sectors =
1087                                 hostdata->madapter_info.port_max_txu[0] >> 9;
1088
1089                 if (hostdata->madapter_info.os_type == 3 &&
1090                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
1091                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
1092                                 hostdata->madapter_info.srp_version);
1093                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
1094                                 MAX_INDIRECT_BUFS);
1095                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
1096                 }
1097
1098                 if (hostdata->madapter_info.os_type == 3) {
1099                         enable_fast_fail(hostdata);
1100                         return;
1101                 }
1102         }
1103
1104         send_srp_login(hostdata);
1105 }
1106
1107 /**
1108  * send_mad_adapter_info: - Sends the mad adapter info request
1109  *      and stores the result so it can be retrieved with
1110  *      sysfs.  We COULD consider causing a failure if the
1111  *      returned SRP version doesn't match ours.
1112  * @hostdata:   ibmvscsi_host_data of host
1113  *
1114  * Returns zero if successful.
1115 */
1116 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
1117 {
1118         struct viosrp_adapter_info *req;
1119         struct srp_event_struct *evt_struct;
1120         unsigned long flags;
1121
1122         evt_struct = get_event_struct(&hostdata->pool);
1123         BUG_ON(!evt_struct);
1124
1125         init_event_struct(evt_struct,
1126                           adapter_info_rsp,
1127                           VIOSRP_MAD_FORMAT,
1128                           info_timeout);
1129
1130         req = &evt_struct->iu.mad.adapter_info;
1131         memset(req, 0x00, sizeof(*req));
1132
1133         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
1134         req->common.length = sizeof(hostdata->madapter_info);
1135         req->buffer = hostdata->adapter_info_addr;
1136
1137         spin_lock_irqsave(hostdata->host->host_lock, flags);
1138         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1139                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
1140         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1141 };
1142
1143 /**
1144  * init_adapter: Start virtual adapter initialization sequence
1145  *
1146  */
1147 static void init_adapter(struct ibmvscsi_host_data *hostdata)
1148 {
1149         send_mad_adapter_info(hostdata);
1150 }
1151
1152 /**
1153  * sync_completion: Signal that a synchronous command has completed
1154  * Note that after returning from this call, the evt_struct is freed.
1155  * the caller waiting on this completion shouldn't touch the evt_struct
1156  * again.
1157  */
1158 static void sync_completion(struct srp_event_struct *evt_struct)
1159 {
1160         /* copy the response back */
1161         if (evt_struct->sync_srp)
1162                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
1163
1164         complete(&evt_struct->comp);
1165 }
1166
1167 /**
1168  * ibmvscsi_abort: Abort a command...from scsi host template
1169  * send this over to the server and wait synchronously for the response
1170  */
1171 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
1172 {
1173         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1174         struct srp_tsk_mgmt *tsk_mgmt;
1175         struct srp_event_struct *evt;
1176         struct srp_event_struct *tmp_evt, *found_evt;
1177         union viosrp_iu srp_rsp;
1178         int rsp_rc;
1179         unsigned long flags;
1180         u16 lun = lun_from_dev(cmd->device);
1181         unsigned long wait_switch = 0;
1182
1183         /* First, find this command in our sent list so we can figure
1184          * out the correct tag
1185          */
1186         spin_lock_irqsave(hostdata->host->host_lock, flags);
1187         wait_switch = jiffies + (init_timeout * HZ);
1188         do {
1189                 found_evt = NULL;
1190                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1191                         if (tmp_evt->cmnd == cmd) {
1192                                 found_evt = tmp_evt;
1193                                 break;
1194                         }
1195                 }
1196
1197                 if (!found_evt) {
1198                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1199                         return SUCCESS;
1200                 }
1201
1202                 evt = get_event_struct(&hostdata->pool);
1203                 if (evt == NULL) {
1204                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1205                         sdev_printk(KERN_ERR, cmd->device,
1206                                 "failed to allocate abort event\n");
1207                         return FAILED;
1208                 }
1209
1210                 init_event_struct(evt,
1211                                   sync_completion,
1212                                   VIOSRP_SRP_FORMAT,
1213                                   abort_timeout);
1214
1215                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1216
1217                 /* Set up an abort SRP command */
1218                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1219                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1220                 tsk_mgmt->lun = ((u64) lun) << 48;
1221                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1222                 tsk_mgmt->task_tag = (u64) found_evt;
1223
1224                 evt->sync_srp = &srp_rsp;
1225
1226                 init_completion(&evt->comp);
1227                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1228
1229                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1230                         break;
1231
1232                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1233                 msleep(10);
1234                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1235         } while (time_before(jiffies, wait_switch));
1236
1237         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1238
1239         if (rsp_rc != 0) {
1240                 sdev_printk(KERN_ERR, cmd->device,
1241                             "failed to send abort() event. rc=%d\n", rsp_rc);
1242                 return FAILED;
1243         }
1244
1245         sdev_printk(KERN_INFO, cmd->device,
1246                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1247                     (((u64) lun) << 48), (u64) found_evt);
1248
1249         wait_for_completion(&evt->comp);
1250
1251         /* make sure we got a good response */
1252         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1253                 if (printk_ratelimit())
1254                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1255                                     srp_rsp.srp.rsp.opcode);
1256                 return FAILED;
1257         }
1258
1259         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1260                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1261         else
1262                 rsp_rc = srp_rsp.srp.rsp.status;
1263
1264         if (rsp_rc) {
1265                 if (printk_ratelimit())
1266                         sdev_printk(KERN_WARNING, cmd->device,
1267                                     "abort code %d for task tag 0x%llx\n",
1268                                     rsp_rc, tsk_mgmt->task_tag);
1269                 return FAILED;
1270         }
1271
1272         /* Because we dropped the spinlock above, it's possible
1273          * The event is no longer in our list.  Make sure it didn't
1274          * complete while we were aborting
1275          */
1276         spin_lock_irqsave(hostdata->host->host_lock, flags);
1277         found_evt = NULL;
1278         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1279                 if (tmp_evt->cmnd == cmd) {
1280                         found_evt = tmp_evt;
1281                         break;
1282                 }
1283         }
1284
1285         if (found_evt == NULL) {
1286                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1287                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1288                             tsk_mgmt->task_tag);
1289                 return SUCCESS;
1290         }
1291
1292         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1293                     tsk_mgmt->task_tag);
1294
1295         cmd->result = (DID_ABORT << 16);
1296         list_del(&found_evt->list);
1297         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1298                        found_evt->hostdata->dev);
1299         free_event_struct(&found_evt->hostdata->pool, found_evt);
1300         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1301         atomic_inc(&hostdata->request_limit);
1302         return SUCCESS;
1303 }
1304
1305 /**
1306  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1307  * template send this over to the server and wait synchronously for the
1308  * response
1309  */
1310 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1311 {
1312         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1313         struct srp_tsk_mgmt *tsk_mgmt;
1314         struct srp_event_struct *evt;
1315         struct srp_event_struct *tmp_evt, *pos;
1316         union viosrp_iu srp_rsp;
1317         int rsp_rc;
1318         unsigned long flags;
1319         u16 lun = lun_from_dev(cmd->device);
1320         unsigned long wait_switch = 0;
1321
1322         spin_lock_irqsave(hostdata->host->host_lock, flags);
1323         wait_switch = jiffies + (init_timeout * HZ);
1324         do {
1325                 evt = get_event_struct(&hostdata->pool);
1326                 if (evt == NULL) {
1327                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1328                         sdev_printk(KERN_ERR, cmd->device,
1329                                 "failed to allocate reset event\n");
1330                         return FAILED;
1331                 }
1332
1333                 init_event_struct(evt,
1334                                   sync_completion,
1335                                   VIOSRP_SRP_FORMAT,
1336                                   reset_timeout);
1337
1338                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1339
1340                 /* Set up a lun reset SRP command */
1341                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1342                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1343                 tsk_mgmt->lun = ((u64) lun) << 48;
1344                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1345
1346                 evt->sync_srp = &srp_rsp;
1347
1348                 init_completion(&evt->comp);
1349                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1350
1351                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1352                         break;
1353
1354                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1355                 msleep(10);
1356                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1357         } while (time_before(jiffies, wait_switch));
1358
1359         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1360
1361         if (rsp_rc != 0) {
1362                 sdev_printk(KERN_ERR, cmd->device,
1363                             "failed to send reset event. rc=%d\n", rsp_rc);
1364                 return FAILED;
1365         }
1366
1367         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1368                     (((u64) lun) << 48));
1369
1370         wait_for_completion(&evt->comp);
1371
1372         /* make sure we got a good response */
1373         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1374                 if (printk_ratelimit())
1375                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1376                                     srp_rsp.srp.rsp.opcode);
1377                 return FAILED;
1378         }
1379
1380         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1381                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1382         else
1383                 rsp_rc = srp_rsp.srp.rsp.status;
1384
1385         if (rsp_rc) {
1386                 if (printk_ratelimit())
1387                         sdev_printk(KERN_WARNING, cmd->device,
1388                                     "reset code %d for task tag 0x%llx\n",
1389                                     rsp_rc, tsk_mgmt->task_tag);
1390                 return FAILED;
1391         }
1392
1393         /* We need to find all commands for this LUN that have not yet been
1394          * responded to, and fail them with DID_RESET
1395          */
1396         spin_lock_irqsave(hostdata->host->host_lock, flags);
1397         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1398                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1399                         if (tmp_evt->cmnd)
1400                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1401                         list_del(&tmp_evt->list);
1402                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1403                                        tmp_evt->hostdata->dev);
1404                         free_event_struct(&tmp_evt->hostdata->pool,
1405                                                    tmp_evt);
1406                         atomic_inc(&hostdata->request_limit);
1407                         if (tmp_evt->cmnd_done)
1408                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1409                         else if (tmp_evt->done)
1410                                 tmp_evt->done(tmp_evt);
1411                 }
1412         }
1413         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1414         return SUCCESS;
1415 }
1416
1417 /**
1418  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1419  * @cmd:        struct scsi_cmnd having problems
1420 */
1421 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1422 {
1423         unsigned long wait_switch = 0;
1424         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1425
1426         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1427
1428         ibmvscsi_reset_host(hostdata);
1429
1430         for (wait_switch = jiffies + (init_timeout * HZ);
1431              time_before(jiffies, wait_switch) &&
1432                      atomic_read(&hostdata->request_limit) < 2;) {
1433
1434                 msleep(10);
1435         }
1436
1437         if (atomic_read(&hostdata->request_limit) <= 0)
1438                 return FAILED;
1439
1440         return SUCCESS;
1441 }
1442
1443 /**
1444  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1445  * @crq:        Command/Response queue
1446  * @hostdata:   ibmvscsi_host_data of host
1447  *
1448 */
1449 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1450                          struct ibmvscsi_host_data *hostdata)
1451 {
1452         long rc;
1453         unsigned long flags;
1454         struct srp_event_struct *evt_struct =
1455             (struct srp_event_struct *)crq->IU_data_ptr;
1456         switch (crq->valid) {
1457         case 0xC0:              /* initialization */
1458                 switch (crq->format) {
1459                 case 0x01:      /* Initialization message */
1460                         dev_info(hostdata->dev, "partner initialized\n");
1461                         /* Send back a response */
1462                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1463                                                          0xC002000000000000LL, 0)) == 0) {
1464                                 /* Now login */
1465                                 init_adapter(hostdata);
1466                         } else {
1467                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1468                         }
1469
1470                         break;
1471                 case 0x02:      /* Initialization response */
1472                         dev_info(hostdata->dev, "partner initialization complete\n");
1473
1474                         /* Now login */
1475                         init_adapter(hostdata);
1476                         break;
1477                 default:
1478                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1479                 }
1480                 return;
1481         case 0xFF:      /* Hypervisor telling us the connection is closed */
1482                 scsi_block_requests(hostdata->host);
1483                 atomic_set(&hostdata->request_limit, 0);
1484                 if (crq->format == 0x06) {
1485                         /* We need to re-setup the interpartition connection */
1486                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1487                         hostdata->client_migrated = 1;
1488                         purge_requests(hostdata, DID_REQUEUE);
1489                         if ((ibmvscsi_ops->reenable_crq_queue(&hostdata->queue,
1490                                                               hostdata)) ||
1491                             (ibmvscsi_ops->send_crq(hostdata,
1492                                                     0xC001000000000000LL, 0))) {
1493                                         atomic_set(&hostdata->request_limit,
1494                                                    -1);
1495                                         dev_err(hostdata->dev, "error after enable\n");
1496                         }
1497                 } else {
1498                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1499                                 crq->format);
1500
1501                         purge_requests(hostdata, DID_ERROR);
1502                         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue,
1503                                                            hostdata)) ||
1504                             (ibmvscsi_ops->send_crq(hostdata,
1505                                                     0xC001000000000000LL, 0))) {
1506                                         atomic_set(&hostdata->request_limit,
1507                                                    -1);
1508                                         dev_err(hostdata->dev, "error after reset\n");
1509                         }
1510                 }
1511                 scsi_unblock_requests(hostdata->host);
1512                 return;
1513         case 0x80:              /* real payload */
1514                 break;
1515         default:
1516                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1517                         crq->valid);
1518                 return;
1519         }
1520
1521         /* The only kind of payload CRQs we should get are responses to
1522          * things we send. Make sure this response is to something we
1523          * actually sent
1524          */
1525         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1526                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1527                        (void *)crq->IU_data_ptr);
1528                 return;
1529         }
1530
1531         if (atomic_read(&evt_struct->free)) {
1532                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1533                         (void *)crq->IU_data_ptr);
1534                 return;
1535         }
1536
1537         if (crq->format == VIOSRP_SRP_FORMAT)
1538                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1539                            &hostdata->request_limit);
1540
1541         del_timer(&evt_struct->timer);
1542
1543         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1544                 evt_struct->cmnd->result = DID_ERROR << 16;
1545         if (evt_struct->done)
1546                 evt_struct->done(evt_struct);
1547         else
1548                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1549
1550         /*
1551          * Lock the host_lock before messing with these structures, since we
1552          * are running in a task context
1553          */
1554         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1555         list_del(&evt_struct->list);
1556         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1557         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1558 }
1559
1560 /**
1561  * ibmvscsi_get_host_config: Send the command to the server to get host
1562  * configuration data.  The data is opaque to us.
1563  */
1564 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1565                                    unsigned char *buffer, int length)
1566 {
1567         struct viosrp_host_config *host_config;
1568         struct srp_event_struct *evt_struct;
1569         unsigned long flags;
1570         dma_addr_t addr;
1571         int rc;
1572
1573         evt_struct = get_event_struct(&hostdata->pool);
1574         if (!evt_struct) {
1575                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1576                 return -1;
1577         }
1578
1579         init_event_struct(evt_struct,
1580                           sync_completion,
1581                           VIOSRP_MAD_FORMAT,
1582                           info_timeout);
1583
1584         host_config = &evt_struct->iu.mad.host_config;
1585
1586         /* Set up a lun reset SRP command */
1587         memset(host_config, 0x00, sizeof(*host_config));
1588         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1589         host_config->common.length = length;
1590         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1591                                                     length,
1592                                                     DMA_BIDIRECTIONAL);
1593
1594         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1595                 if (!firmware_has_feature(FW_FEATURE_CMO))
1596                         dev_err(hostdata->dev,
1597                                 "dma_mapping error getting host config\n");
1598                 free_event_struct(&hostdata->pool, evt_struct);
1599                 return -1;
1600         }
1601
1602         init_completion(&evt_struct->comp);
1603         spin_lock_irqsave(hostdata->host->host_lock, flags);
1604         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1605         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1606         if (rc == 0)
1607                 wait_for_completion(&evt_struct->comp);
1608         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1609
1610         return rc;
1611 }
1612
1613 /**
1614  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1615  * @sdev:       struct scsi_device device to configure
1616  *
1617  * Enable allow_restart for a device if it is a disk.  Adjust the
1618  * queue_depth here also as is required by the documentation for
1619  * struct scsi_host_template.
1620  */
1621 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1622 {
1623         struct Scsi_Host *shost = sdev->host;
1624         unsigned long lock_flags = 0;
1625
1626         spin_lock_irqsave(shost->host_lock, lock_flags);
1627         if (sdev->type == TYPE_DISK) {
1628                 sdev->allow_restart = 1;
1629                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1630         }
1631         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1632         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1633         return 0;
1634 }
1635
1636 /**
1637  * ibmvscsi_change_queue_depth - Change the device's queue depth
1638  * @sdev:       scsi device struct
1639  * @qdepth:     depth to set
1640  *
1641  * Return value:
1642  *      actual depth set
1643  **/
1644 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
1645 {
1646         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1647                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1648
1649         scsi_adjust_queue_depth(sdev, 0, qdepth);
1650         return sdev->queue_depth;
1651 }
1652
1653 /* ------------------------------------------------------------
1654  * sysfs attributes
1655  */
1656 static ssize_t show_host_vhost_loc(struct device *dev,
1657                                    struct device_attribute *attr, char *buf)
1658 {
1659         struct Scsi_Host *shost = class_to_shost(dev);
1660         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1661         int len;
1662
1663         len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
1664                        hostdata->caps.loc);
1665         return len;
1666 }
1667
1668 static struct device_attribute ibmvscsi_host_vhost_loc = {
1669         .attr = {
1670                  .name = "vhost_loc",
1671                  .mode = S_IRUGO,
1672                  },
1673         .show = show_host_vhost_loc,
1674 };
1675
1676 static ssize_t show_host_vhost_name(struct device *dev,
1677                                     struct device_attribute *attr, char *buf)
1678 {
1679         struct Scsi_Host *shost = class_to_shost(dev);
1680         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1681         int len;
1682
1683         len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
1684                        hostdata->caps.name);
1685         return len;
1686 }
1687
1688 static struct device_attribute ibmvscsi_host_vhost_name = {
1689         .attr = {
1690                  .name = "vhost_name",
1691                  .mode = S_IRUGO,
1692                  },
1693         .show = show_host_vhost_name,
1694 };
1695
1696 static ssize_t show_host_srp_version(struct device *dev,
1697                                      struct device_attribute *attr, char *buf)
1698 {
1699         struct Scsi_Host *shost = class_to_shost(dev);
1700         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1701         int len;
1702
1703         len = snprintf(buf, PAGE_SIZE, "%s\n",
1704                        hostdata->madapter_info.srp_version);
1705         return len;
1706 }
1707
1708 static struct device_attribute ibmvscsi_host_srp_version = {
1709         .attr = {
1710                  .name = "srp_version",
1711                  .mode = S_IRUGO,
1712                  },
1713         .show = show_host_srp_version,
1714 };
1715
1716 static ssize_t show_host_partition_name(struct device *dev,
1717                                         struct device_attribute *attr,
1718                                         char *buf)
1719 {
1720         struct Scsi_Host *shost = class_to_shost(dev);
1721         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1722         int len;
1723
1724         len = snprintf(buf, PAGE_SIZE, "%s\n",
1725                        hostdata->madapter_info.partition_name);
1726         return len;
1727 }
1728
1729 static struct device_attribute ibmvscsi_host_partition_name = {
1730         .attr = {
1731                  .name = "partition_name",
1732                  .mode = S_IRUGO,
1733                  },
1734         .show = show_host_partition_name,
1735 };
1736
1737 static ssize_t show_host_partition_number(struct device *dev,
1738                                           struct device_attribute *attr,
1739                                           char *buf)
1740 {
1741         struct Scsi_Host *shost = class_to_shost(dev);
1742         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1743         int len;
1744
1745         len = snprintf(buf, PAGE_SIZE, "%d\n",
1746                        hostdata->madapter_info.partition_number);
1747         return len;
1748 }
1749
1750 static struct device_attribute ibmvscsi_host_partition_number = {
1751         .attr = {
1752                  .name = "partition_number",
1753                  .mode = S_IRUGO,
1754                  },
1755         .show = show_host_partition_number,
1756 };
1757
1758 static ssize_t show_host_mad_version(struct device *dev,
1759                                      struct device_attribute *attr, char *buf)
1760 {
1761         struct Scsi_Host *shost = class_to_shost(dev);
1762         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1763         int len;
1764
1765         len = snprintf(buf, PAGE_SIZE, "%d\n",
1766                        hostdata->madapter_info.mad_version);
1767         return len;
1768 }
1769
1770 static struct device_attribute ibmvscsi_host_mad_version = {
1771         .attr = {
1772                  .name = "mad_version",
1773                  .mode = S_IRUGO,
1774                  },
1775         .show = show_host_mad_version,
1776 };
1777
1778 static ssize_t show_host_os_type(struct device *dev,
1779                                  struct device_attribute *attr, char *buf)
1780 {
1781         struct Scsi_Host *shost = class_to_shost(dev);
1782         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1783         int len;
1784
1785         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1786         return len;
1787 }
1788
1789 static struct device_attribute ibmvscsi_host_os_type = {
1790         .attr = {
1791                  .name = "os_type",
1792                  .mode = S_IRUGO,
1793                  },
1794         .show = show_host_os_type,
1795 };
1796
1797 static ssize_t show_host_config(struct device *dev,
1798                                 struct device_attribute *attr, char *buf)
1799 {
1800         struct Scsi_Host *shost = class_to_shost(dev);
1801         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1802
1803         /* returns null-terminated host config data */
1804         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1805                 return strlen(buf);
1806         else
1807                 return 0;
1808 }
1809
1810 static struct device_attribute ibmvscsi_host_config = {
1811         .attr = {
1812                  .name = "config",
1813                  .mode = S_IRUGO,
1814                  },
1815         .show = show_host_config,
1816 };
1817
1818 static struct device_attribute *ibmvscsi_attrs[] = {
1819         &ibmvscsi_host_vhost_loc,
1820         &ibmvscsi_host_vhost_name,
1821         &ibmvscsi_host_srp_version,
1822         &ibmvscsi_host_partition_name,
1823         &ibmvscsi_host_partition_number,
1824         &ibmvscsi_host_mad_version,
1825         &ibmvscsi_host_os_type,
1826         &ibmvscsi_host_config,
1827         NULL
1828 };
1829
1830 /* ------------------------------------------------------------
1831  * SCSI driver registration
1832  */
1833 static struct scsi_host_template driver_template = {
1834         .module = THIS_MODULE,
1835         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1836         .proc_name = "ibmvscsi",
1837         .queuecommand = ibmvscsi_queuecommand,
1838         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1839         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1840         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1841         .slave_configure = ibmvscsi_slave_configure,
1842         .change_queue_depth = ibmvscsi_change_queue_depth,
1843         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1844         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1845         .this_id = -1,
1846         .sg_tablesize = SG_ALL,
1847         .use_clustering = ENABLE_CLUSTERING,
1848         .shost_attrs = ibmvscsi_attrs,
1849 };
1850
1851 /**
1852  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1853  *
1854  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1855  *
1856  * Return value:
1857  *      Number of bytes of IO data the driver will need to perform well.
1858  */
1859 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1860 {
1861         /* iu_storage data allocated in initialize_event_pool */
1862         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
1863
1864         /* add io space for sg data */
1865         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1866                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1867
1868         return desired_io;
1869 }
1870
1871 /**
1872  * Called by bus code for each adapter
1873  */
1874 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1875 {
1876         struct ibmvscsi_host_data *hostdata;
1877         struct Scsi_Host *host;
1878         struct device *dev = &vdev->dev;
1879         struct srp_rport_identifiers ids;
1880         struct srp_rport *rport;
1881         unsigned long wait_switch = 0;
1882         int rc;
1883
1884         dev_set_drvdata(&vdev->dev, NULL);
1885
1886         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1887         if (!host) {
1888                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1889                 goto scsi_host_alloc_failed;
1890         }
1891
1892         host->transportt = ibmvscsi_transport_template;
1893         hostdata = shost_priv(host);
1894         memset(hostdata, 0x00, sizeof(*hostdata));
1895         INIT_LIST_HEAD(&hostdata->sent);
1896         hostdata->host = host;
1897         hostdata->dev = dev;
1898         atomic_set(&hostdata->request_limit, -1);
1899         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1900
1901         if (map_persist_bufs(hostdata)) {
1902                 dev_err(&vdev->dev, "couldn't map persistent buffers\n");
1903                 goto persist_bufs_failed;
1904         }
1905
1906         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_events);
1907         if (rc != 0 && rc != H_RESOURCE) {
1908                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1909                 goto init_crq_failed;
1910         }
1911         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
1912                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1913                 goto init_pool_failed;
1914         }
1915
1916         host->max_lun = 8;
1917         host->max_id = max_id;
1918         host->max_channel = max_channel;
1919         host->max_cmd_len = 16;
1920
1921         if (scsi_add_host(hostdata->host, hostdata->dev))
1922                 goto add_host_failed;
1923
1924         /* we don't have a proper target_port_id so let's use the fake one */
1925         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1926                sizeof(ids.port_id));
1927         ids.roles = SRP_RPORT_ROLE_TARGET;
1928         rport = srp_rport_add(host, &ids);
1929         if (IS_ERR(rport))
1930                 goto add_srp_port_failed;
1931
1932         /* Try to send an initialization message.  Note that this is allowed
1933          * to fail if the other end is not acive.  In that case we don't
1934          * want to scan
1935          */
1936         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1937             || rc == H_RESOURCE) {
1938                 /*
1939                  * Wait around max init_timeout secs for the adapter to finish
1940                  * initializing. When we are done initializing, we will have a
1941                  * valid request_limit.  We don't want Linux scanning before
1942                  * we are ready.
1943                  */
1944                 for (wait_switch = jiffies + (init_timeout * HZ);
1945                      time_before(jiffies, wait_switch) &&
1946                      atomic_read(&hostdata->request_limit) < 2;) {
1947
1948                         msleep(10);
1949                 }
1950
1951                 /* if we now have a valid request_limit, initiate a scan */
1952                 if (atomic_read(&hostdata->request_limit) > 0)
1953                         scsi_scan_host(host);
1954         }
1955
1956         dev_set_drvdata(&vdev->dev, hostdata);
1957         return 0;
1958
1959       add_srp_port_failed:
1960         scsi_remove_host(hostdata->host);
1961       add_host_failed:
1962         release_event_pool(&hostdata->pool, hostdata);
1963       init_pool_failed:
1964         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_events);
1965       init_crq_failed:
1966         unmap_persist_bufs(hostdata);
1967       persist_bufs_failed:
1968         scsi_host_put(host);
1969       scsi_host_alloc_failed:
1970         return -1;
1971 }
1972
1973 static int ibmvscsi_remove(struct vio_dev *vdev)
1974 {
1975         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
1976         unmap_persist_bufs(hostdata);
1977         release_event_pool(&hostdata->pool, hostdata);
1978         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
1979                                         max_events);
1980
1981         srp_remove_host(hostdata->host);
1982         scsi_remove_host(hostdata->host);
1983         scsi_host_put(hostdata->host);
1984
1985         return 0;
1986 }
1987
1988 /**
1989  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
1990  * support.
1991  */
1992 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1993         {"vscsi", "IBM,v-scsi"},
1994         { "", "" }
1995 };
1996 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1997
1998 static struct vio_driver ibmvscsi_driver = {
1999         .id_table = ibmvscsi_device_table,
2000         .probe = ibmvscsi_probe,
2001         .remove = ibmvscsi_remove,
2002         .get_desired_dma = ibmvscsi_get_desired_dma,
2003         .driver = {
2004                 .name = "ibmvscsi",
2005                 .owner = THIS_MODULE,
2006         }
2007 };
2008
2009 static struct srp_function_template ibmvscsi_transport_functions = {
2010 };
2011
2012 int __init ibmvscsi_module_init(void)
2013 {
2014         int ret;
2015
2016         /* Ensure we have two requests to do error recovery */
2017         driver_template.can_queue = max_requests;
2018         max_events = max_requests + 2;
2019
2020         if (firmware_has_feature(FW_FEATURE_ISERIES))
2021                 ibmvscsi_ops = &iseriesvscsi_ops;
2022         else if (firmware_has_feature(FW_FEATURE_VIO))
2023                 ibmvscsi_ops = &rpavscsi_ops;
2024         else
2025                 return -ENODEV;
2026
2027         ibmvscsi_transport_template =
2028                 srp_attach_transport(&ibmvscsi_transport_functions);
2029         if (!ibmvscsi_transport_template)
2030                 return -ENOMEM;
2031
2032         ret = vio_register_driver(&ibmvscsi_driver);
2033         if (ret)
2034                 srp_release_transport(ibmvscsi_transport_template);
2035         return ret;
2036 }
2037
2038 void __exit ibmvscsi_module_exit(void)
2039 {
2040         vio_unregister_driver(&ibmvscsi_driver);
2041         srp_release_transport(ibmvscsi_transport_template);
2042 }
2043
2044 module_init(ibmvscsi_module_init);
2045 module_exit(ibmvscsi_module_exit);