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-robin 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/slab.h>
  74 #include <linux/of.h>
  75 #include <linux/pm.h>
  76 #include <linux/kthread.h>
  77 #include <asm/firmware.h>
  78 #include <asm/vio.h>
  79 #include <scsi/scsi.h>
  80 #include <scsi/scsi_cmnd.h>
  81 #include <scsi/scsi_host.h>
  82 #include <scsi/scsi_device.h>
  83 #include <scsi/scsi_transport_srp.h>
  84 #include "ibmvscsi.h"
  85
  86 /* The values below are somewhat arbitrary default values, but
  87  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
  88  * Note that there are 3 bits of channel value, 6 bits of id, and
  89  * 5 bits of LUN.
  90  */
  91 static int max_id = 64;
  92 static int max_channel = 3;
  93 static int init_timeout = 300;
  94 static int login_timeout = 60;
  95 static int info_timeout = 30;
  96 static int abort_timeout = 60;
  97 static int reset_timeout = 60;
  98 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
  99 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
 100 static int fast_fail = 1;
 101 static int client_reserve = 1;
 102
 103 static struct scsi_transport_template *ibmvscsi_transport_template;
 104
 105 #define IBMVSCSI_VERSION "1.5.8"
 106
 107 static struct ibmvscsi_ops *ibmvscsi_ops;
 108
 109 MODULE_DESCRIPTION("IBM Virtual SCSI");
 110 MODULE_AUTHOR("Dave Boutcher");
 111 MODULE_LICENSE("GPL");
 112 MODULE_VERSION(IBMVSCSI_VERSION);
 113
 114 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
 115 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
 116 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
 117 MODULE_PARM_DESC(max_channel, "Largest channel value");
 118 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
 119 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
 120 module_param_named(max_requests, max_requests, int, S_IRUGO);
 121 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
 122 module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR);
 123 MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]");
 124 module_param_named(client_reserve, client_reserve, int, S_IRUGO );
 125 MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release");
 126
 127 /* ------------------------------------------------------------
 128  * Routines for the event pool and event structs
 129  */
 130 /**
 131  * initialize_event_pool: - Allocates and initializes the event pool for a host
 132  * @pool:       event_pool to be initialized
 133  * @size:       Number of events in pool
 134  * @hostdata:   ibmvscsi_host_data who owns the event pool
 135  *
 136  * Returns zero on success.
 137 */
 138 static int initialize_event_pool(struct event_pool *pool,
 139                                  int size, struct ibmvscsi_host_data *hostdata)
 140 {
 141         int i;
 142
 143         pool->size = size;
 144         pool->next = 0;
 145         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
 146         if (!pool->events)
 147                 return -ENOMEM;
 148
 149         pool->iu_storage =
 150             dma_alloc_coherent(hostdata->dev,
 151                                pool->size * sizeof(*pool->iu_storage),
 152                                &pool->iu_token, 0);
 153         if (!pool->iu_storage) {
 154                 kfree(pool->events);
 155                 return -ENOMEM;
 156         }
 157
 158         for (i = 0; i < pool->size; ++i) {
 159                 struct srp_event_struct *evt = &pool->events[i];
 160                 memset(&evt->crq, 0x00, sizeof(evt->crq));
 161                 atomic_set(&evt->free, 1);
 162                 evt->crq.valid = 0x80;
 163                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
 164                 evt->crq.IU_data_ptr = pool->iu_token +
 165                         sizeof(*evt->xfer_iu) * i;
 166                 evt->xfer_iu = pool->iu_storage + i;
 167                 evt->hostdata = hostdata;
 168                 evt->ext_list = NULL;
 169                 evt->ext_list_token = 0;
 170         }
 171
 172         return 0;
 173 }
 174
 175 /**
 176  * release_event_pool: - Frees memory of an event pool of a host
 177  * @pool:       event_pool to be released
 178  * @hostdata:   ibmvscsi_host_data who owns the even pool
 179  *
 180  * Returns zero on success.
 181 */
 182 static void release_event_pool(struct event_pool *pool,
 183                                struct ibmvscsi_host_data *hostdata)
 184 {
 185         int i, in_use = 0;
 186         for (i = 0; i < pool->size; ++i) {
 187                 if (atomic_read(&pool->events[i].free) != 1)
 188                         ++in_use;
 189                 if (pool->events[i].ext_list) {
 190                         dma_free_coherent(hostdata->dev,
 191                                   SG_ALL * sizeof(struct srp_direct_buf),
 192                                   pool->events[i].ext_list,
 193                                   pool->events[i].ext_list_token);
 194                 }
 195         }
 196         if (in_use)
 197                 dev_warn(hostdata->dev, "releasing event pool with %d "
 198                          "events still in use?\n", in_use);
 199         kfree(pool->events);
 200         dma_free_coherent(hostdata->dev,
 201                           pool->size * sizeof(*pool->iu_storage),
 202                           pool->iu_storage, pool->iu_token);
 203 }
 204
 205 /**
 206  * valid_event_struct: - Determines if event is valid.
 207  * @pool:       event_pool that contains the event
 208  * @evt:        srp_event_struct to be checked for validity
 209  *
 210  * Returns zero if event is invalid, one otherwise.
 211 */
 212 static int valid_event_struct(struct event_pool *pool,
 213                                 struct srp_event_struct *evt)
 214 {
 215         int index = evt - pool->events;
 216         if (index < 0 || index >= pool->size)   /* outside of bounds */
 217                 return 0;
 218         if (evt != pool->events + index)        /* unaligned */
 219                 return 0;
 220         return 1;
 221 }
 222
 223 /**
 224  * ibmvscsi_free-event_struct: - Changes status of event to "free"
 225  * @pool:       event_pool that contains the event
 226  * @evt:        srp_event_struct to be modified
 227  *
 228 */
 229 static void free_event_struct(struct event_pool *pool,
 230                                        struct srp_event_struct *evt)
 231 {
 232         if (!valid_event_struct(pool, evt)) {
 233                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
 234                         "(not in pool %p)\n", evt, pool->events);
 235                 return;
 236         }
 237         if (atomic_inc_return(&evt->free) != 1) {
 238                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
 239                         "which is not in use!\n", evt);
 240                 return;
 241         }
 242 }
 243
 244 /**
 245  * get_evt_struct: - Gets the next free event in pool
 246  * @pool:       event_pool that contains the events to be searched
 247  *
 248  * Returns the next event in "free" state, and NULL if none are free.
 249  * Note that no synchronization is done here, we assume the host_lock
 250  * will syncrhonze things.
 251 */
 252 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
 253 {
 254         int i;
 255         int poolsize = pool->size;
 256         int offset = pool->next;
 257
 258         for (i = 0; i < poolsize; i++) {
 259                 offset = (offset + 1) % poolsize;
 260                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
 261                         pool->next = offset;
 262                         return &pool->events[offset];
 263                 }
 264         }
 265
 266         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
 267         return NULL;
 268 }
 269
 270 /**
 271  * init_event_struct: Initialize fields in an event struct that are always
 272  *                    required.
 273  * @evt:        The event
 274  * @done:       Routine to call when the event is responded to
 275  * @format:     SRP or MAD format
 276  * @timeout:    timeout value set in the CRQ
 277  */
 278 static void init_event_struct(struct srp_event_struct *evt_struct,
 279                               void (*done) (struct srp_event_struct *),
 280                               u8 format,
 281                               int timeout)
 282 {
 283         evt_struct->cmnd = NULL;
 284         evt_struct->cmnd_done = NULL;
 285         evt_struct->sync_srp = NULL;
 286         evt_struct->crq.format = format;
 287         evt_struct->crq.timeout = timeout;
 288         evt_struct->done = done;
 289 }
 290
 291 /* ------------------------------------------------------------
 292  * Routines for receiving SCSI responses from the hosting partition
 293  */
 294
 295 /**
 296  * set_srp_direction: Set the fields in the srp related to data
 297  *     direction and number of buffers based on the direction in
 298  *     the scsi_cmnd and the number of buffers
 299  */
 300 static void set_srp_direction(struct scsi_cmnd *cmd,
 301                               struct srp_cmd *srp_cmd,
 302                               int numbuf)
 303 {
 304         u8 fmt;
 305
 306         if (numbuf == 0)
 307                 return;
 308
 309         if (numbuf == 1)
 310                 fmt = SRP_DATA_DESC_DIRECT;
 311         else {
 312                 fmt = SRP_DATA_DESC_INDIRECT;
 313                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
 314
 315                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
 316                         srp_cmd->data_out_desc_cnt = numbuf;
 317                 else
 318                         srp_cmd->data_in_desc_cnt = numbuf;
 319         }
 320
 321         if (cmd->sc_data_direction == DMA_TO_DEVICE)
 322                 srp_cmd->buf_fmt = fmt << 4;
 323         else
 324                 srp_cmd->buf_fmt = fmt;
 325 }
 326
 327 /**
 328  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
 329  * @cmd:        srp_cmd whose additional_data member will be unmapped
 330  * @dev:        device for which the memory is mapped
 331  *
 332 */
 333 static void unmap_cmd_data(struct srp_cmd *cmd,
 334                            struct srp_event_struct *evt_struct,
 335                            struct device *dev)
 336 {
 337         u8 out_fmt, in_fmt;
 338
 339         out_fmt = cmd->buf_fmt >> 4;
 340         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
 341
 342         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
 343                 return;
 344
 345         if (evt_struct->cmnd)
 346                 scsi_dma_unmap(evt_struct->cmnd);
 347 }
 348
 349 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
 350                        struct srp_direct_buf *md)
 351 {
 352         int i;
 353         struct scatterlist *sg;
 354         u64 total_length = 0;
 355
 356         scsi_for_each_sg(cmd, sg, nseg, i) {
 357                 struct srp_direct_buf *descr = md + i;
 358                 descr->va = sg_dma_address(sg);
 359                 descr->len = sg_dma_len(sg);
 360                 descr->key = 0;
 361                 total_length += sg_dma_len(sg);
 362         }
 363         return total_length;
 364 }
 365
 366 /**
 367  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
 368  * @cmd:        Scsi_Cmnd with the scatterlist
 369  * @srp_cmd:    srp_cmd that contains the memory descriptor
 370  * @dev:        device for which to map dma memory
 371  *
 372  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 373  * Returns 1 on success.
 374 */
 375 static int map_sg_data(struct scsi_cmnd *cmd,
 376                        struct srp_event_struct *evt_struct,
 377                        struct srp_cmd *srp_cmd, struct device *dev)
 378 {
 379
 380         int sg_mapped;
 381         u64 total_length = 0;
 382         struct srp_direct_buf *data =
 383                 (struct srp_direct_buf *) srp_cmd->add_data;
 384         struct srp_indirect_buf *indirect =
 385                 (struct srp_indirect_buf *) data;
 386
 387         sg_mapped = scsi_dma_map(cmd);
 388         if (!sg_mapped)
 389                 return 1;
 390         else if (sg_mapped < 0)
 391                 return 0;
 392
 393         set_srp_direction(cmd, srp_cmd, sg_mapped);
 394
 395         /* special case; we can use a single direct descriptor */
 396         if (sg_mapped == 1) {
 397                 map_sg_list(cmd, sg_mapped, data);
 398                 return 1;
 399         }
 400
 401         indirect->table_desc.va = 0;
 402         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
 403         indirect->table_desc.key = 0;
 404
 405         if (sg_mapped <= MAX_INDIRECT_BUFS) {
 406                 total_length = map_sg_list(cmd, sg_mapped,
 407                                            &indirect->desc_list[0]);
 408                 indirect->len = total_length;
 409                 return 1;
 410         }
 411
 412         /* get indirect table */
 413         if (!evt_struct->ext_list) {
 414                 evt_struct->ext_list = (struct srp_direct_buf *)
 415                         dma_alloc_coherent(dev,
 416                                            SG_ALL * sizeof(struct srp_direct_buf),
 417                                            &evt_struct->ext_list_token, 0);
 418                 if (!evt_struct->ext_list) {
 419                         if (!firmware_has_feature(FW_FEATURE_CMO))
 420                                 sdev_printk(KERN_ERR, cmd->device,
 421                                             "Can't allocate memory "
 422                                             "for indirect table\n");
 423                         scsi_dma_unmap(cmd);
 424                         return 0;
 425                 }
 426         }
 427
 428         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
 429
 430         indirect->len = total_length;
 431         indirect->table_desc.va = evt_struct->ext_list_token;
 432         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
 433         memcpy(indirect->desc_list, evt_struct->ext_list,
 434                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
 435         return 1;
 436 }
 437
 438 /**
 439  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
 440  * @cmd:        struct scsi_cmnd with the memory to be mapped
 441  * @srp_cmd:    srp_cmd that contains the memory descriptor
 442  * @dev:        dma device for which to map dma memory
 443  *
 444  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
 445  * Returns 1 on success.
 446 */
 447 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
 448                                 struct srp_event_struct *evt_struct,
 449                                 struct srp_cmd *srp_cmd, struct device *dev)
 450 {
 451         switch (cmd->sc_data_direction) {
 452         case DMA_FROM_DEVICE:
 453         case DMA_TO_DEVICE:
 454                 break;
 455         case DMA_NONE:
 456                 return 1;
 457         case DMA_BIDIRECTIONAL:
 458                 sdev_printk(KERN_ERR, cmd->device,
 459                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
 460                 return 0;
 461         default:
 462                 sdev_printk(KERN_ERR, cmd->device,
 463                             "Unknown data direction 0x%02x; can't map!\n",
 464                             cmd->sc_data_direction);
 465                 return 0;
 466         }
 467
 468         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
 469 }
 470
 471 /**
 472  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
 473  * @hostdata:    the adapter
 474  */
 475 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
 476 {
 477         struct srp_event_struct *evt;
 478         unsigned long flags;
 479
 480         spin_lock_irqsave(hostdata->host->host_lock, flags);
 481         while (!list_empty(&hostdata->sent)) {
 482                 evt = list_first_entry(&hostdata->sent, struct srp_event_struct, list);
 483                 list_del(&evt->list);
 484                 del_timer(&evt->timer);
 485
 486                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 487                 if (evt->cmnd) {
 488                         evt->cmnd->result = (error_code << 16);
 489                         unmap_cmd_data(&evt->iu.srp.cmd, evt,
 490                                        evt->hostdata->dev);
 491                         if (evt->cmnd_done)
 492                                 evt->cmnd_done(evt->cmnd);
 493                 } else if (evt->done)
 494                         evt->done(evt);
 495                 free_event_struct(&evt->hostdata->pool, evt);
 496                 spin_lock_irqsave(hostdata->host->host_lock, flags);
 497         }
 498         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 499 }
 500
 501 /**
 502  * ibmvscsi_reset_host - Reset the connection to the server
 503  * @hostdata:   struct ibmvscsi_host_data to reset
 504 */
 505 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
 506 {
 507         scsi_block_requests(hostdata->host);
 508         atomic_set(&hostdata->request_limit, 0);
 509
 510         purge_requests(hostdata, DID_ERROR);
 511         hostdata->reset_crq = 1;
 512         wake_up(&hostdata->work_wait_q);
 513 }
 514
 515 /**
 516  * ibmvscsi_timeout - Internal command timeout handler
 517  * @evt_struct: struct srp_event_struct that timed out
 518  *
 519  * Called when an internally generated command times out
 520 */
 521 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
 522 {
 523         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 524
 525         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
 526                 evt_struct->iu.srp.cmd.opcode);
 527
 528         ibmvscsi_reset_host(hostdata);
 529 }
 530
 531
 532 /* ------------------------------------------------------------
 533  * Routines for sending and receiving SRPs
 534  */
 535 /**
 536  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 537  * @evt_struct: evt_struct to be sent
 538  * @hostdata:   ibmvscsi_host_data of host
 539  * @timeout:    timeout in seconds - 0 means do not time command
 540  *
 541  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 542  * Note that this routine assumes that host_lock is held for synchronization
 543 */
 544 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 545                                    struct ibmvscsi_host_data *hostdata,
 546                                    unsigned long timeout)
 547 {
 548         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 549         int request_status = 0;
 550         int rc;
 551
 552         /* If we have exhausted our request limit, just fail this request,
 553          * unless it is for a reset or abort.
 554          * Note that there are rare cases involving driver generated requests
 555          * (such as task management requests) that the mid layer may think we
 556          * can handle more requests (can_queue) when we actually can't
 557          */
 558         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
 559                 request_status =
 560                         atomic_dec_if_positive(&hostdata->request_limit);
 561                 /* If request limit was -1 when we started, it is now even
 562                  * less than that
 563                  */
 564                 if (request_status < -1)
 565                         goto send_error;
 566                 /* Otherwise, we may have run out of requests. */
 567                 /* If request limit was 0 when we started the adapter is in the
 568                  * process of performing a login with the server adapter, or
 569                  * we may have run out of requests.
 570                  */
 571                 else if (request_status == -1 &&
 572                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
 573                         goto send_busy;
 574                 /* Abort and reset calls should make it through.
 575                  * Nothing except abort and reset should use the last two
 576                  * slots unless we had two or less to begin with.
 577                  */
 578                 else if (request_status < 2 &&
 579                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
 580                         /* In the case that we have less than two requests
 581                          * available, check the server limit as a combination
 582                          * of the request limit and the number of requests
 583                          * in-flight (the size of the send list).  If the
 584                          * server limit is greater than 2, return busy so
 585                          * that the last two are reserved for reset and abort.
 586                          */
 587                         int server_limit = request_status;
 588                         struct srp_event_struct *tmp_evt;
 589
 590                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 591                                 server_limit++;
 592                         }
 593
 594                         if (server_limit > 2)
 595                                 goto send_busy;
 596                 }
 597         }
 598
 599         /* Copy the IU into the transfer area */
 600         *evt_struct->xfer_iu = evt_struct->iu;
 601         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 602
 603         /* Add this to the sent list.  We need to do this
 604          * before we actually send
 605          * in case it comes back REALLY fast
 606          */
 607         list_add_tail(&evt_struct->list, &hostdata->sent);
 608
 609         init_timer(&evt_struct->timer);
 610         if (timeout) {
 611                 evt_struct->timer.data = (unsigned long) evt_struct;
 612                 evt_struct->timer.expires = jiffies + (timeout * HZ);
 613                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
 614                 add_timer(&evt_struct->timer);
 615         }
 616
 617         if ((rc =
 618              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 619                 list_del(&evt_struct->list);
 620                 del_timer(&evt_struct->timer);
 621
 622                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
 623                  * Firmware will send a CRQ with a transport event (0xFF) to
 624                  * tell this client what has happened to the transport.  This
 625                  * will be handled in ibmvscsi_handle_crq()
 626                  */
 627                 if (rc == H_CLOSED) {
 628                         dev_warn(hostdata->dev, "send warning. "
 629                                  "Receive queue closed, will retry.\n");
 630                         goto send_busy;
 631                 }
 632                 dev_err(hostdata->dev, "send error %d\n", rc);
 633                 atomic_inc(&hostdata->request_limit);
 634                 goto send_error;
 635         }
 636
 637         return 0;
 638
 639  send_busy:
 640         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 641
 642         free_event_struct(&hostdata->pool, evt_struct);
 643         if (request_status != -1)
 644                 atomic_inc(&hostdata->request_limit);
 645         return SCSI_MLQUEUE_HOST_BUSY;
 646
 647  send_error:
 648         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 649
 650         if (evt_struct->cmnd != NULL) {
 651                 evt_struct->cmnd->result = DID_ERROR << 16;
 652                 evt_struct->cmnd_done(evt_struct->cmnd);
 653         } else if (evt_struct->done)
 654                 evt_struct->done(evt_struct);
 655
 656         free_event_struct(&hostdata->pool, evt_struct);
 657         return 0;
 658 }
 659
 660 /**
 661  * handle_cmd_rsp: -  Handle responses from commands
 662  * @evt_struct: srp_event_struct to be handled
 663  *
 664  * Used as a callback by when sending scsi cmds.
 665  * Gets called by ibmvscsi_handle_crq()
 666 */
 667 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 668 {
 669         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 670         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 671
 672         if (unlikely(rsp->opcode != SRP_RSP)) {
 673                 if (printk_ratelimit())
 674                         dev_warn(evt_struct->hostdata->dev,
 675                                  "bad SRP RSP type %d\n", rsp->opcode);
 676         }
 677
 678         if (cmnd) {
 679                 cmnd->result |= rsp->status;
 680                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 681                         memcpy(cmnd->sense_buffer,
 682                                rsp->data,
 683                                rsp->sense_data_len);
 684                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 685                                evt_struct,
 686                                evt_struct->hostdata->dev);
 687
 688                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 689                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
 690                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 691                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
 692         }
 693
 694         if (evt_struct->cmnd_done)
 695                 evt_struct->cmnd_done(cmnd);
 696 }
 697
 698 /**
 699  * lun_from_dev: - Returns the lun of the scsi device
 700  * @dev:        struct scsi_device
 701  *
 702 */
 703 static inline u16 lun_from_dev(struct scsi_device *dev)
 704 {
 705         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 706 }
 707
 708 /**
 709  * ibmvscsi_queue: - The queuecommand function of the scsi template
 710  * @cmd:        struct scsi_cmnd to be executed
 711  * @done:       Callback function to be called when cmd is completed
 712 */
 713 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
 714                                  void (*done) (struct scsi_cmnd *))
 715 {
 716         struct srp_cmd *srp_cmd;
 717         struct srp_event_struct *evt_struct;
 718         struct srp_indirect_buf *indirect;
 719         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
 720         u16 lun = lun_from_dev(cmnd->device);
 721         u8 out_fmt, in_fmt;
 722
 723         cmnd->result = (DID_OK << 16);
 724         evt_struct = get_event_struct(&hostdata->pool);
 725         if (!evt_struct)
 726                 return SCSI_MLQUEUE_HOST_BUSY;
 727
 728         /* Set up the actual SRP IU */
 729         srp_cmd = &evt_struct->iu.srp.cmd;
 730         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 731         srp_cmd->opcode = SRP_CMD;
 732         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
 733         srp_cmd->lun = ((u64) lun) << 48;
 734
 735         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 736                 if (!firmware_has_feature(FW_FEATURE_CMO))
 737                         sdev_printk(KERN_ERR, cmnd->device,
 738                                     "couldn't convert cmd to srp_cmd\n");
 739                 free_event_struct(&hostdata->pool, evt_struct);
 740                 return SCSI_MLQUEUE_HOST_BUSY;
 741         }
 742
 743         init_event_struct(evt_struct,
 744                           handle_cmd_rsp,
 745                           VIOSRP_SRP_FORMAT,
 746                           cmnd->request->timeout/HZ);
 747
 748         evt_struct->cmnd = cmnd;
 749         evt_struct->cmnd_done = done;
 750
 751         /* Fix up dma address of the buffer itself */
 752         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 753         out_fmt = srp_cmd->buf_fmt >> 4;
 754         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 755         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 756              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 757             indirect->table_desc.va == 0) {
 758                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 759                         offsetof(struct srp_cmd, add_data) +
 760                         offsetof(struct srp_indirect_buf, desc_list);
 761         }
 762
 763         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
 764 }
 765
 766 /* ------------------------------------------------------------
 767  * Routines for driver initialization
 768  */
 769
 770 /**
 771  * map_persist_bufs: - Pre-map persistent data for adapter logins
 772  * @hostdata:   ibmvscsi_host_data of host
 773  *
 774  * Map the capabilities and adapter info DMA buffers to avoid runtime failures.
 775  * Return 1 on error, 0 on success.
 776  */
 777 static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
 778 {
 779
 780         hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
 781                                              sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 782
 783         if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
 784                 dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
 785                 return 1;
 786         }
 787
 788         hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
 789                                                      &hostdata->madapter_info,
 790                                                      sizeof(hostdata->madapter_info),
 791                                                      DMA_BIDIRECTIONAL);
 792         if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
 793                 dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
 794                 dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 795                                  sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 796                 return 1;
 797         }
 798
 799         return 0;
 800 }
 801
 802 /**
 803  * unmap_persist_bufs: - Unmap persistent data needed for adapter logins
 804  * @hostdata:   ibmvscsi_host_data of host
 805  *
 806  * Unmap the capabilities and adapter info DMA buffers
 807  */
 808 static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
 809 {
 810         dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 811                          sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 812
 813         dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
 814                          sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
 815 }
 816
 817 /**
 818  * login_rsp: - Handle response to SRP login request
 819  * @evt_struct: srp_event_struct with the response
 820  *
 821  * Used as a "done" callback by when sending srp_login. Gets called
 822  * by ibmvscsi_handle_crq()
 823 */
 824 static void login_rsp(struct srp_event_struct *evt_struct)
 825 {
 826         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 827         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 828         case SRP_LOGIN_RSP:     /* it worked! */
 829                 break;
 830         case SRP_LOGIN_REJ:     /* refused! */
 831                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
 832                          evt_struct->xfer_iu->srp.login_rej.reason);
 833                 /* Login failed.  */
 834                 atomic_set(&hostdata->request_limit, -1);
 835                 return;
 836         default:
 837                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
 838                         evt_struct->xfer_iu->srp.login_rsp.opcode);
 839                 /* Login failed.  */
 840                 atomic_set(&hostdata->request_limit, -1);
 841                 return;
 842         }
 843
 844         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
 845         hostdata->client_migrated = 0;
 846
 847         /* Now we know what the real request-limit is.
 848          * This value is set rather than added to request_limit because
 849          * request_limit could have been set to -1 by this client.
 850          */
 851         atomic_set(&hostdata->request_limit,
 852                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 853
 854         /* If we had any pending I/Os, kick them */
 855         scsi_unblock_requests(hostdata->host);
 856 }
 857
 858 /**
 859  * send_srp_login: - Sends the srp login
 860  * @hostdata:   ibmvscsi_host_data of host
 861  *
 862  * Returns zero if successful.
 863 */
 864 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 865 {
 866         int rc;
 867         unsigned long flags;
 868         struct srp_login_req *login;
 869         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 870
 871         BUG_ON(!evt_struct);
 872         init_event_struct(evt_struct, login_rsp,
 873                           VIOSRP_SRP_FORMAT, login_timeout);
 874
 875         login = &evt_struct->iu.srp.login_req;
 876         memset(login, 0, sizeof(*login));
 877         login->opcode = SRP_LOGIN_REQ;
 878         login->req_it_iu_len = sizeof(union srp_iu);
 879         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 880
 881         spin_lock_irqsave(hostdata->host->host_lock, flags);
 882         /* Start out with a request limit of 0, since this is negotiated in
 883          * the login request we are just sending and login requests always
 884          * get sent by the driver regardless of request_limit.
 885          */
 886         atomic_set(&hostdata->request_limit, 0);
 887
 888         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
 889         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 890         dev_info(hostdata->dev, "sent SRP login\n");
 891         return rc;
 892 };
 893
 894 /**
 895  * capabilities_rsp: - Handle response to MAD adapter capabilities request
 896  * @evt_struct: srp_event_struct with the response
 897  *
 898  * Used as a "done" callback by when sending adapter_info.
 899  */
 900 static void capabilities_rsp(struct srp_event_struct *evt_struct)
 901 {
 902         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 903
 904         if (evt_struct->xfer_iu->mad.capabilities.common.status) {
 905                 dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
 906                         evt_struct->xfer_iu->mad.capabilities.common.status);
 907         } else {
 908                 if (hostdata->caps.migration.common.server_support != SERVER_SUPPORTS_CAP)
 909                         dev_info(hostdata->dev, "Partition migration not supported\n");
 910
 911                 if (client_reserve) {
 912                         if (hostdata->caps.reserve.common.server_support ==
 913                             SERVER_SUPPORTS_CAP)
 914                                 dev_info(hostdata->dev, "Client reserve enabled\n");
 915                         else
 916                                 dev_info(hostdata->dev, "Client reserve not supported\n");
 917                 }
 918         }
 919
 920         send_srp_login(hostdata);
 921 }
 922
 923 /**
 924  * send_mad_capabilities: - Sends the mad capabilities request
 925  *      and stores the result so it can be retrieved with
 926  * @hostdata:   ibmvscsi_host_data of host
 927  */
 928 static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
 929 {
 930         struct viosrp_capabilities *req;
 931         struct srp_event_struct *evt_struct;
 932         unsigned long flags;
 933         struct device_node *of_node = hostdata->dev->of_node;
 934         const char *location;
 935
 936         evt_struct = get_event_struct(&hostdata->pool);
 937         BUG_ON(!evt_struct);
 938
 939         init_event_struct(evt_struct, capabilities_rsp,
 940                           VIOSRP_MAD_FORMAT, info_timeout);
 941
 942         req = &evt_struct->iu.mad.capabilities;
 943         memset(req, 0, sizeof(*req));
 944
 945         hostdata->caps.flags = CAP_LIST_SUPPORTED;
 946         if (hostdata->client_migrated)
 947                 hostdata->caps.flags |= CLIENT_MIGRATED;
 948
 949         strncpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
 950                 sizeof(hostdata->caps.name));
 951         hostdata->caps.name[sizeof(hostdata->caps.name) - 1] = '\0';
 952
 953         location = of_get_property(of_node, "ibm,loc-code", NULL);
 954         location = location ? location : dev_name(hostdata->dev);
 955         strncpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
 956         hostdata->caps.loc[sizeof(hostdata->caps.loc) - 1] = '\0';
 957
 958         req->common.type = VIOSRP_CAPABILITIES_TYPE;
 959         req->buffer = hostdata->caps_addr;
 960
 961         hostdata->caps.migration.common.cap_type = MIGRATION_CAPABILITIES;
 962         hostdata->caps.migration.common.length = sizeof(hostdata->caps.migration);
 963         hostdata->caps.migration.common.server_support = SERVER_SUPPORTS_CAP;
 964         hostdata->caps.migration.ecl = 1;
 965
 966         if (client_reserve) {
 967                 hostdata->caps.reserve.common.cap_type = RESERVATION_CAPABILITIES;
 968                 hostdata->caps.reserve.common.length = sizeof(hostdata->caps.reserve);
 969                 hostdata->caps.reserve.common.server_support = SERVER_SUPPORTS_CAP;
 970                 hostdata->caps.reserve.type = CLIENT_RESERVE_SCSI_2;
 971                 req->common.length = sizeof(hostdata->caps);
 972         } else
 973                 req->common.length = sizeof(hostdata->caps) - sizeof(hostdata->caps.reserve);
 974
 975         spin_lock_irqsave(hostdata->host->host_lock, flags);
 976         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
 977                 dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
 978         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 979 };
 980
 981 /**
 982  * fast_fail_rsp: - Handle response to MAD enable fast fail
 983  * @evt_struct: srp_event_struct with the response
 984  *
 985  * Used as a "done" callback by when sending enable fast fail. Gets called
 986  * by ibmvscsi_handle_crq()
 987  */
 988 static void fast_fail_rsp(struct srp_event_struct *evt_struct)
 989 {
 990         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 991         u8 status = evt_struct->xfer_iu->mad.fast_fail.common.status;
 992
 993         if (status == VIOSRP_MAD_NOT_SUPPORTED)
 994                 dev_err(hostdata->dev, "fast_fail not supported in server\n");
 995         else if (status == VIOSRP_MAD_FAILED)
 996                 dev_err(hostdata->dev, "fast_fail request failed\n");
 997         else if (status != VIOSRP_MAD_SUCCESS)
 998                 dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
 999
1000         send_mad_capabilities(hostdata);
1001 }
1002
1003 /**
1004  * init_host - Start host initialization
1005  * @hostdata:   ibmvscsi_host_data of host
1006  *
1007  * Returns zero if successful.
1008  */
1009 static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
1010 {
1011         int rc;
1012         unsigned long flags;
1013         struct viosrp_fast_fail *fast_fail_mad;
1014         struct srp_event_struct *evt_struct;
1015
1016         if (!fast_fail) {
1017                 send_mad_capabilities(hostdata);
1018                 return 0;
1019         }
1020
1021         evt_struct = get_event_struct(&hostdata->pool);
1022         BUG_ON(!evt_struct);
1023
1024         init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
1025
1026         fast_fail_mad = &evt_struct->iu.mad.fast_fail;
1027         memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
1028         fast_fail_mad->common.type = VIOSRP_ENABLE_FAST_FAIL;
1029         fast_fail_mad->common.length = sizeof(*fast_fail_mad);
1030
1031         spin_lock_irqsave(hostdata->host->host_lock, flags);
1032         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1033         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1034         return rc;
1035 }
1036
1037 /**
1038  * adapter_info_rsp: - Handle response to MAD adapter info request
1039  * @evt_struct: srp_event_struct with the response
1040  *
1041  * Used as a "done" callback by when sending adapter_info. Gets called
1042  * by ibmvscsi_handle_crq()
1043 */
1044 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
1045 {
1046         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1047
1048         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
1049                 dev_err(hostdata->dev, "error %d getting adapter info\n",
1050                         evt_struct->xfer_iu->mad.adapter_info.common.status);
1051         } else {
1052                 dev_info(hostdata->dev, "host srp version: %s, "
1053                          "host partition %s (%d), OS %d, max io %u\n",
1054                          hostdata->madapter_info.srp_version,
1055                          hostdata->madapter_info.partition_name,
1056                          hostdata->madapter_info.partition_number,
1057                          hostdata->madapter_info.os_type,
1058                          hostdata->madapter_info.port_max_txu[0]);
1059
1060                 if (hostdata->madapter_info.port_max_txu[0])
1061                         hostdata->host->max_sectors =
1062                                 hostdata->madapter_info.port_max_txu[0] >> 9;
1063
1064                 if (hostdata->madapter_info.os_type == 3 &&
1065                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
1066                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
1067                                 hostdata->madapter_info.srp_version);
1068                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
1069                                 MAX_INDIRECT_BUFS);
1070                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
1071                 }
1072
1073                 if (hostdata->madapter_info.os_type == 3) {
1074                         enable_fast_fail(hostdata);
1075                         return;
1076                 }
1077         }
1078
1079         send_srp_login(hostdata);
1080 }
1081
1082 /**
1083  * send_mad_adapter_info: - Sends the mad adapter info request
1084  *      and stores the result so it can be retrieved with
1085  *      sysfs.  We COULD consider causing a failure if the
1086  *      returned SRP version doesn't match ours.
1087  * @hostdata:   ibmvscsi_host_data of host
1088  *
1089  * Returns zero if successful.
1090 */
1091 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
1092 {
1093         struct viosrp_adapter_info *req;
1094         struct srp_event_struct *evt_struct;
1095         unsigned long flags;
1096
1097         evt_struct = get_event_struct(&hostdata->pool);
1098         BUG_ON(!evt_struct);
1099
1100         init_event_struct(evt_struct,
1101                           adapter_info_rsp,
1102                           VIOSRP_MAD_FORMAT,
1103                           info_timeout);
1104
1105         req = &evt_struct->iu.mad.adapter_info;
1106         memset(req, 0x00, sizeof(*req));
1107
1108         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
1109         req->common.length = sizeof(hostdata->madapter_info);
1110         req->buffer = hostdata->adapter_info_addr;
1111
1112         spin_lock_irqsave(hostdata->host->host_lock, flags);
1113         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1114                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
1115         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1116 };
1117
1118 /**
1119  * init_adapter: Start virtual adapter initialization sequence
1120  *
1121  */
1122 static void init_adapter(struct ibmvscsi_host_data *hostdata)
1123 {
1124         send_mad_adapter_info(hostdata);
1125 }
1126
1127 /**
1128  * sync_completion: Signal that a synchronous command has completed
1129  * Note that after returning from this call, the evt_struct is freed.
1130  * the caller waiting on this completion shouldn't touch the evt_struct
1131  * again.
1132  */
1133 static void sync_completion(struct srp_event_struct *evt_struct)
1134 {
1135         /* copy the response back */
1136         if (evt_struct->sync_srp)
1137                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
1138
1139         complete(&evt_struct->comp);
1140 }
1141
1142 /**
1143  * ibmvscsi_abort: Abort a command...from scsi host template
1144  * send this over to the server and wait synchronously for the response
1145  */
1146 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
1147 {
1148         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1149         struct srp_tsk_mgmt *tsk_mgmt;
1150         struct srp_event_struct *evt;
1151         struct srp_event_struct *tmp_evt, *found_evt;
1152         union viosrp_iu srp_rsp;
1153         int rsp_rc;
1154         unsigned long flags;
1155         u16 lun = lun_from_dev(cmd->device);
1156         unsigned long wait_switch = 0;
1157
1158         /* First, find this command in our sent list so we can figure
1159          * out the correct tag
1160          */
1161         spin_lock_irqsave(hostdata->host->host_lock, flags);
1162         wait_switch = jiffies + (init_timeout * HZ);
1163         do {
1164                 found_evt = NULL;
1165                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1166                         if (tmp_evt->cmnd == cmd) {
1167                                 found_evt = tmp_evt;
1168                                 break;
1169                         }
1170                 }
1171
1172                 if (!found_evt) {
1173                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1174                         return SUCCESS;
1175                 }
1176
1177                 evt = get_event_struct(&hostdata->pool);
1178                 if (evt == NULL) {
1179                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1180                         sdev_printk(KERN_ERR, cmd->device,
1181                                 "failed to allocate abort event\n");
1182                         return FAILED;
1183                 }
1184
1185                 init_event_struct(evt,
1186                                   sync_completion,
1187                                   VIOSRP_SRP_FORMAT,
1188                                   abort_timeout);
1189
1190                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1191
1192                 /* Set up an abort SRP command */
1193                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1194                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1195                 tsk_mgmt->lun = ((u64) lun) << 48;
1196                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1197                 tsk_mgmt->task_tag = (u64) found_evt;
1198
1199                 evt->sync_srp = &srp_rsp;
1200
1201                 init_completion(&evt->comp);
1202                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1203
1204                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1205                         break;
1206
1207                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1208                 msleep(10);
1209                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1210         } while (time_before(jiffies, wait_switch));
1211
1212         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1213
1214         if (rsp_rc != 0) {
1215                 sdev_printk(KERN_ERR, cmd->device,
1216                             "failed to send abort() event. rc=%d\n", rsp_rc);
1217                 return FAILED;
1218         }
1219
1220         sdev_printk(KERN_INFO, cmd->device,
1221                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1222                     (((u64) lun) << 48), (u64) found_evt);
1223
1224         wait_for_completion(&evt->comp);
1225
1226         /* make sure we got a good response */
1227         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1228                 if (printk_ratelimit())
1229                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1230                                     srp_rsp.srp.rsp.opcode);
1231                 return FAILED;
1232         }
1233
1234         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1235                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1236         else
1237                 rsp_rc = srp_rsp.srp.rsp.status;
1238
1239         if (rsp_rc) {
1240                 if (printk_ratelimit())
1241                         sdev_printk(KERN_WARNING, cmd->device,
1242                                     "abort code %d for task tag 0x%llx\n",
1243                                     rsp_rc, tsk_mgmt->task_tag);
1244                 return FAILED;
1245         }
1246
1247         /* Because we dropped the spinlock above, it's possible
1248          * The event is no longer in our list.  Make sure it didn't
1249          * complete while we were aborting
1250          */
1251         spin_lock_irqsave(hostdata->host->host_lock, flags);
1252         found_evt = NULL;
1253         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1254                 if (tmp_evt->cmnd == cmd) {
1255                         found_evt = tmp_evt;
1256                         break;
1257                 }
1258         }
1259
1260         if (found_evt == NULL) {
1261                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1262                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1263                             tsk_mgmt->task_tag);
1264                 return SUCCESS;
1265         }
1266
1267         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1268                     tsk_mgmt->task_tag);
1269
1270         cmd->result = (DID_ABORT << 16);
1271         list_del(&found_evt->list);
1272         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1273                        found_evt->hostdata->dev);
1274         free_event_struct(&found_evt->hostdata->pool, found_evt);
1275         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1276         atomic_inc(&hostdata->request_limit);
1277         return SUCCESS;
1278 }
1279
1280 /**
1281  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1282  * template send this over to the server and wait synchronously for the
1283  * response
1284  */
1285 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1286 {
1287         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1288         struct srp_tsk_mgmt *tsk_mgmt;
1289         struct srp_event_struct *evt;
1290         struct srp_event_struct *tmp_evt, *pos;
1291         union viosrp_iu srp_rsp;
1292         int rsp_rc;
1293         unsigned long flags;
1294         u16 lun = lun_from_dev(cmd->device);
1295         unsigned long wait_switch = 0;
1296
1297         spin_lock_irqsave(hostdata->host->host_lock, flags);
1298         wait_switch = jiffies + (init_timeout * HZ);
1299         do {
1300                 evt = get_event_struct(&hostdata->pool);
1301                 if (evt == NULL) {
1302                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1303                         sdev_printk(KERN_ERR, cmd->device,
1304                                 "failed to allocate reset event\n");
1305                         return FAILED;
1306                 }
1307
1308                 init_event_struct(evt,
1309                                   sync_completion,
1310                                   VIOSRP_SRP_FORMAT,
1311                                   reset_timeout);
1312
1313                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1314
1315                 /* Set up a lun reset SRP command */
1316                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1317                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1318                 tsk_mgmt->lun = ((u64) lun) << 48;
1319                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1320
1321                 evt->sync_srp = &srp_rsp;
1322
1323                 init_completion(&evt->comp);
1324                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1325
1326                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1327                         break;
1328
1329                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1330                 msleep(10);
1331                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1332         } while (time_before(jiffies, wait_switch));
1333
1334         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1335
1336         if (rsp_rc != 0) {
1337                 sdev_printk(KERN_ERR, cmd->device,
1338                             "failed to send reset event. rc=%d\n", rsp_rc);
1339                 return FAILED;
1340         }
1341
1342         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1343                     (((u64) lun) << 48));
1344
1345         wait_for_completion(&evt->comp);
1346
1347         /* make sure we got a good response */
1348         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1349                 if (printk_ratelimit())
1350                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1351                                     srp_rsp.srp.rsp.opcode);
1352                 return FAILED;
1353         }
1354
1355         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1356                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1357         else
1358                 rsp_rc = srp_rsp.srp.rsp.status;
1359
1360         if (rsp_rc) {
1361                 if (printk_ratelimit())
1362                         sdev_printk(KERN_WARNING, cmd->device,
1363                                     "reset code %d for task tag 0x%llx\n",
1364                                     rsp_rc, tsk_mgmt->task_tag);
1365                 return FAILED;
1366         }
1367
1368         /* We need to find all commands for this LUN that have not yet been
1369          * responded to, and fail them with DID_RESET
1370          */
1371         spin_lock_irqsave(hostdata->host->host_lock, flags);
1372         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1373                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1374                         if (tmp_evt->cmnd)
1375                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1376                         list_del(&tmp_evt->list);
1377                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1378                                        tmp_evt->hostdata->dev);
1379                         free_event_struct(&tmp_evt->hostdata->pool,
1380                                                    tmp_evt);
1381                         atomic_inc(&hostdata->request_limit);
1382                         if (tmp_evt->cmnd_done)
1383                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1384                         else if (tmp_evt->done)
1385                                 tmp_evt->done(tmp_evt);
1386                 }
1387         }
1388         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1389         return SUCCESS;
1390 }
1391
1392 /**
1393  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1394  * @cmd:        struct scsi_cmnd having problems
1395 */
1396 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1397 {
1398         unsigned long wait_switch = 0;
1399         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1400
1401         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1402
1403         ibmvscsi_reset_host(hostdata);
1404
1405         for (wait_switch = jiffies + (init_timeout * HZ);
1406              time_before(jiffies, wait_switch) &&
1407                      atomic_read(&hostdata->request_limit) < 2;) {
1408
1409                 msleep(10);
1410         }
1411
1412         if (atomic_read(&hostdata->request_limit) <= 0)
1413                 return FAILED;
1414
1415         return SUCCESS;
1416 }
1417
1418 /**
1419  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1420  * @crq:        Command/Response queue
1421  * @hostdata:   ibmvscsi_host_data of host
1422  *
1423 */
1424 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1425                          struct ibmvscsi_host_data *hostdata)
1426 {
1427         long rc;
1428         unsigned long flags;
1429         struct srp_event_struct *evt_struct =
1430             (struct srp_event_struct *)crq->IU_data_ptr;
1431         switch (crq->valid) {
1432         case 0xC0:              /* initialization */
1433                 switch (crq->format) {
1434                 case 0x01:      /* Initialization message */
1435                         dev_info(hostdata->dev, "partner initialized\n");
1436                         /* Send back a response */
1437                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1438                                                          0xC002000000000000LL, 0)) == 0) {
1439                                 /* Now login */
1440                                 init_adapter(hostdata);
1441                         } else {
1442                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1443                         }
1444
1445                         break;
1446                 case 0x02:      /* Initialization response */
1447                         dev_info(hostdata->dev, "partner initialization complete\n");
1448
1449                         /* Now login */
1450                         init_adapter(hostdata);
1451                         break;
1452                 default:
1453                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1454                 }
1455                 return;
1456         case 0xFF:      /* Hypervisor telling us the connection is closed */
1457                 scsi_block_requests(hostdata->host);
1458                 atomic_set(&hostdata->request_limit, 0);
1459                 if (crq->format == 0x06) {
1460                         /* We need to re-setup the interpartition connection */
1461                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1462                         hostdata->client_migrated = 1;
1463                         hostdata->reenable_crq = 1;
1464                         purge_requests(hostdata, DID_REQUEUE);
1465                         wake_up(&hostdata->work_wait_q);
1466                 } else {
1467                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1468                                 crq->format);
1469                         ibmvscsi_reset_host(hostdata);
1470                 }
1471                 return;
1472         case 0x80:              /* real payload */
1473                 break;
1474         default:
1475                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1476                         crq->valid);
1477                 return;
1478         }
1479
1480         /* The only kind of payload CRQs we should get are responses to
1481          * things we send. Make sure this response is to something we
1482          * actually sent
1483          */
1484         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1485                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1486                        (void *)crq->IU_data_ptr);
1487                 return;
1488         }
1489
1490         if (atomic_read(&evt_struct->free)) {
1491                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1492                         (void *)crq->IU_data_ptr);
1493                 return;
1494         }
1495
1496         if (crq->format == VIOSRP_SRP_FORMAT)
1497                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1498                            &hostdata->request_limit);
1499
1500         del_timer(&evt_struct->timer);
1501
1502         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1503                 evt_struct->cmnd->result = DID_ERROR << 16;
1504         if (evt_struct->done)
1505                 evt_struct->done(evt_struct);
1506         else
1507                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1508
1509         /*
1510          * Lock the host_lock before messing with these structures, since we
1511          * are running in a task context
1512          */
1513         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1514         list_del(&evt_struct->list);
1515         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1516         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1517 }
1518
1519 /**
1520  * ibmvscsi_get_host_config: Send the command to the server to get host
1521  * configuration data.  The data is opaque to us.
1522  */
1523 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1524                                    unsigned char *buffer, int length)
1525 {
1526         struct viosrp_host_config *host_config;
1527         struct srp_event_struct *evt_struct;
1528         unsigned long flags;
1529         dma_addr_t addr;
1530         int rc;
1531
1532         evt_struct = get_event_struct(&hostdata->pool);
1533         if (!evt_struct) {
1534                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1535                 return -1;
1536         }
1537
1538         init_event_struct(evt_struct,
1539                           sync_completion,
1540                           VIOSRP_MAD_FORMAT,
1541                           info_timeout);
1542
1543         host_config = &evt_struct->iu.mad.host_config;
1544
1545         /* Set up a lun reset SRP command */
1546         memset(host_config, 0x00, sizeof(*host_config));
1547         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1548         host_config->common.length = length;
1549         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1550                                                     length,
1551                                                     DMA_BIDIRECTIONAL);
1552
1553         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1554                 if (!firmware_has_feature(FW_FEATURE_CMO))
1555                         dev_err(hostdata->dev,
1556                                 "dma_mapping error getting host config\n");
1557                 free_event_struct(&hostdata->pool, evt_struct);
1558                 return -1;
1559         }
1560
1561         init_completion(&evt_struct->comp);
1562         spin_lock_irqsave(hostdata->host->host_lock, flags);
1563         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1564         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1565         if (rc == 0)
1566                 wait_for_completion(&evt_struct->comp);
1567         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1568
1569         return rc;
1570 }
1571
1572 /**
1573  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1574  * @sdev:       struct scsi_device device to configure
1575  *
1576  * Enable allow_restart for a device if it is a disk.  Adjust the
1577  * queue_depth here also as is required by the documentation for
1578  * struct scsi_host_template.
1579  */
1580 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1581 {
1582         struct Scsi_Host *shost = sdev->host;
1583         unsigned long lock_flags = 0;
1584
1585         spin_lock_irqsave(shost->host_lock, lock_flags);
1586         if (sdev->type == TYPE_DISK) {
1587                 sdev->allow_restart = 1;
1588                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1589         }
1590         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1591         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1592         return 0;
1593 }
1594
1595 /**
1596  * ibmvscsi_change_queue_depth - Change the device's queue depth
1597  * @sdev:       scsi device struct
1598  * @qdepth:     depth to set
1599  * @reason:     calling context
1600  *
1601  * Return value:
1602  *      actual depth set
1603  **/
1604 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth,
1605                                        int reason)
1606 {
1607         if (reason != SCSI_QDEPTH_DEFAULT)
1608                 return -EOPNOTSUPP;
1609
1610         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1611                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1612
1613         scsi_adjust_queue_depth(sdev, 0, qdepth);
1614         return sdev->queue_depth;
1615 }
1616
1617 /* ------------------------------------------------------------
1618  * sysfs attributes
1619  */
1620 static ssize_t show_host_vhost_loc(struct device *dev,
1621                                    struct device_attribute *attr, char *buf)
1622 {
1623         struct Scsi_Host *shost = class_to_shost(dev);
1624         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1625         int len;
1626
1627         len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
1628                        hostdata->caps.loc);
1629         return len;
1630 }
1631
1632 static struct device_attribute ibmvscsi_host_vhost_loc = {
1633         .attr = {
1634                  .name = "vhost_loc",
1635                  .mode = S_IRUGO,
1636                  },
1637         .show = show_host_vhost_loc,
1638 };
1639
1640 static ssize_t show_host_vhost_name(struct device *dev,
1641                                     struct device_attribute *attr, char *buf)
1642 {
1643         struct Scsi_Host *shost = class_to_shost(dev);
1644         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1645         int len;
1646
1647         len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
1648                        hostdata->caps.name);
1649         return len;
1650 }
1651
1652 static struct device_attribute ibmvscsi_host_vhost_name = {
1653         .attr = {
1654                  .name = "vhost_name",
1655                  .mode = S_IRUGO,
1656                  },
1657         .show = show_host_vhost_name,
1658 };
1659
1660 static ssize_t show_host_srp_version(struct device *dev,
1661                                      struct device_attribute *attr, char *buf)
1662 {
1663         struct Scsi_Host *shost = class_to_shost(dev);
1664         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1665         int len;
1666
1667         len = snprintf(buf, PAGE_SIZE, "%s\n",
1668                        hostdata->madapter_info.srp_version);
1669         return len;
1670 }
1671
1672 static struct device_attribute ibmvscsi_host_srp_version = {
1673         .attr = {
1674                  .name = "srp_version",
1675                  .mode = S_IRUGO,
1676                  },
1677         .show = show_host_srp_version,
1678 };
1679
1680 static ssize_t show_host_partition_name(struct device *dev,
1681                                         struct device_attribute *attr,
1682                                         char *buf)
1683 {
1684         struct Scsi_Host *shost = class_to_shost(dev);
1685         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1686         int len;
1687
1688         len = snprintf(buf, PAGE_SIZE, "%s\n",
1689                        hostdata->madapter_info.partition_name);
1690         return len;
1691 }
1692
1693 static struct device_attribute ibmvscsi_host_partition_name = {
1694         .attr = {
1695                  .name = "partition_name",
1696                  .mode = S_IRUGO,
1697                  },
1698         .show = show_host_partition_name,
1699 };
1700
1701 static ssize_t show_host_partition_number(struct device *dev,
1702                                           struct device_attribute *attr,
1703                                           char *buf)
1704 {
1705         struct Scsi_Host *shost = class_to_shost(dev);
1706         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1707         int len;
1708
1709         len = snprintf(buf, PAGE_SIZE, "%d\n",
1710                        hostdata->madapter_info.partition_number);
1711         return len;
1712 }
1713
1714 static struct device_attribute ibmvscsi_host_partition_number = {
1715         .attr = {
1716                  .name = "partition_number",
1717                  .mode = S_IRUGO,
1718                  },
1719         .show = show_host_partition_number,
1720 };
1721
1722 static ssize_t show_host_mad_version(struct device *dev,
1723                                      struct device_attribute *attr, char *buf)
1724 {
1725         struct Scsi_Host *shost = class_to_shost(dev);
1726         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1727         int len;
1728
1729         len = snprintf(buf, PAGE_SIZE, "%d\n",
1730                        hostdata->madapter_info.mad_version);
1731         return len;
1732 }
1733
1734 static struct device_attribute ibmvscsi_host_mad_version = {
1735         .attr = {
1736                  .name = "mad_version",
1737                  .mode = S_IRUGO,
1738                  },
1739         .show = show_host_mad_version,
1740 };
1741
1742 static ssize_t show_host_os_type(struct device *dev,
1743                                  struct device_attribute *attr, char *buf)
1744 {
1745         struct Scsi_Host *shost = class_to_shost(dev);
1746         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1747         int len;
1748
1749         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1750         return len;
1751 }
1752
1753 static struct device_attribute ibmvscsi_host_os_type = {
1754         .attr = {
1755                  .name = "os_type",
1756                  .mode = S_IRUGO,
1757                  },
1758         .show = show_host_os_type,
1759 };
1760
1761 static ssize_t show_host_config(struct device *dev,
1762                                 struct device_attribute *attr, char *buf)
1763 {
1764         struct Scsi_Host *shost = class_to_shost(dev);
1765         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1766
1767         /* returns null-terminated host config data */
1768         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1769                 return strlen(buf);
1770         else
1771                 return 0;
1772 }
1773
1774 static struct device_attribute ibmvscsi_host_config = {
1775         .attr = {
1776                  .name = "config",
1777                  .mode = S_IRUGO,
1778                  },
1779         .show = show_host_config,
1780 };
1781
1782 static struct device_attribute *ibmvscsi_attrs[] = {
1783         &ibmvscsi_host_vhost_loc,
1784         &ibmvscsi_host_vhost_name,
1785         &ibmvscsi_host_srp_version,
1786         &ibmvscsi_host_partition_name,
1787         &ibmvscsi_host_partition_number,
1788         &ibmvscsi_host_mad_version,
1789         &ibmvscsi_host_os_type,
1790         &ibmvscsi_host_config,
1791         NULL
1792 };
1793
1794 /* ------------------------------------------------------------
1795  * SCSI driver registration
1796  */
1797 static struct scsi_host_template driver_template = {
1798         .module = THIS_MODULE,
1799         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1800         .proc_name = "ibmvscsi",
1801         .queuecommand = ibmvscsi_queuecommand,
1802         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1803         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1804         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1805         .slave_configure = ibmvscsi_slave_configure,
1806         .change_queue_depth = ibmvscsi_change_queue_depth,
1807         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1808         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1809         .this_id = -1,
1810         .sg_tablesize = SG_ALL,
1811         .use_clustering = ENABLE_CLUSTERING,
1812         .shost_attrs = ibmvscsi_attrs,
1813 };
1814
1815 /**
1816  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1817  *
1818  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1819  *
1820  * Return value:
1821  *      Number of bytes of IO data the driver will need to perform well.
1822  */
1823 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1824 {
1825         /* iu_storage data allocated in initialize_event_pool */
1826         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
1827
1828         /* add io space for sg data */
1829         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1830                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1831
1832         return desired_io;
1833 }
1834
1835 static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata)
1836 {
1837         int rc;
1838         char *action = "reset";
1839
1840         if (hostdata->reset_crq) {
1841                 smp_rmb();
1842                 hostdata->reset_crq = 0;
1843
1844                 rc = ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata);
1845                 if (!rc)
1846                         rc = ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0);
1847                 if (!rc)
1848                         rc = vio_enable_interrupts(to_vio_dev(hostdata->dev));
1849         } else if (hostdata->reenable_crq) {
1850                 smp_rmb();
1851                 action = "enable";
1852                 rc = ibmvscsi_ops->reenable_crq_queue(&hostdata->queue, hostdata);
1853                 hostdata->reenable_crq = 0;
1854                 if (!rc)
1855                         rc = ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0);
1856         } else
1857                 return;
1858
1859         if (rc) {
1860                 atomic_set(&hostdata->request_limit, -1);
1861                 dev_err(hostdata->dev, "error after %s\n", action);
1862         }
1863
1864         scsi_unblock_requests(hostdata->host);
1865 }
1866
1867 static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata)
1868 {
1869         if (kthread_should_stop())
1870                 return 1;
1871         else if (hostdata->reset_crq) {
1872                 smp_rmb();
1873                 return 1;
1874         } else if (hostdata->reenable_crq) {
1875                 smp_rmb();
1876                 return 1;
1877         }
1878
1879         return 0;
1880 }
1881
1882 static int ibmvscsi_work(void *data)
1883 {
1884         struct ibmvscsi_host_data *hostdata = data;
1885         int rc;
1886
1887         set_user_nice(current, -20);
1888
1889         while (1) {
1890                 rc = wait_event_interruptible(hostdata->work_wait_q,
1891                                               ibmvscsi_work_to_do(hostdata));
1892
1893                 BUG_ON(rc);
1894
1895                 if (kthread_should_stop())
1896                         break;
1897
1898                 ibmvscsi_do_work(hostdata);
1899         }
1900
1901         return 0;
1902 }
1903
1904 /**
1905  * Called by bus code for each adapter
1906  */
1907 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1908 {
1909         struct ibmvscsi_host_data *hostdata;
1910         struct Scsi_Host *host;
1911         struct device *dev = &vdev->dev;
1912         struct srp_rport_identifiers ids;
1913         struct srp_rport *rport;
1914         unsigned long wait_switch = 0;
1915         int rc;
1916
1917         dev_set_drvdata(&vdev->dev, NULL);
1918
1919         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1920         if (!host) {
1921                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1922                 goto scsi_host_alloc_failed;
1923         }
1924
1925         host->transportt = ibmvscsi_transport_template;
1926         hostdata = shost_priv(host);
1927         memset(hostdata, 0x00, sizeof(*hostdata));
1928         INIT_LIST_HEAD(&hostdata->sent);
1929         init_waitqueue_head(&hostdata->work_wait_q);
1930         hostdata->host = host;
1931         hostdata->dev = dev;
1932         atomic_set(&hostdata->request_limit, -1);
1933         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1934
1935         if (map_persist_bufs(hostdata)) {
1936                 dev_err(&vdev->dev, "couldn't map persistent buffers\n");
1937                 goto persist_bufs_failed;
1938         }
1939
1940         hostdata->work_thread = kthread_run(ibmvscsi_work, hostdata, "%s_%d",
1941                                             "ibmvscsi", host->host_no);
1942
1943         if (IS_ERR(hostdata->work_thread)) {
1944                 dev_err(&vdev->dev, "couldn't initialize kthread. rc=%ld\n",
1945                         PTR_ERR(hostdata->work_thread));
1946                 goto init_crq_failed;
1947         }
1948
1949         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_events);
1950         if (rc != 0 && rc != H_RESOURCE) {
1951                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1952                 goto kill_kthread;
1953         }
1954         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
1955                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1956                 goto init_pool_failed;
1957         }
1958
1959         host->max_lun = 8;
1960         host->max_id = max_id;
1961         host->max_channel = max_channel;
1962         host->max_cmd_len = 16;
1963
1964         if (scsi_add_host(hostdata->host, hostdata->dev))
1965                 goto add_host_failed;
1966
1967         /* we don't have a proper target_port_id so let's use the fake one */
1968         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1969                sizeof(ids.port_id));
1970         ids.roles = SRP_RPORT_ROLE_TARGET;
1971         rport = srp_rport_add(host, &ids);
1972         if (IS_ERR(rport))
1973                 goto add_srp_port_failed;
1974
1975         /* Try to send an initialization message.  Note that this is allowed
1976          * to fail if the other end is not acive.  In that case we don't
1977          * want to scan
1978          */
1979         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1980             || rc == H_RESOURCE) {
1981                 /*
1982                  * Wait around max init_timeout secs for the adapter to finish
1983                  * initializing. When we are done initializing, we will have a
1984                  * valid request_limit.  We don't want Linux scanning before
1985                  * we are ready.
1986                  */
1987                 for (wait_switch = jiffies + (init_timeout * HZ);
1988                      time_before(jiffies, wait_switch) &&
1989                      atomic_read(&hostdata->request_limit) < 2;) {
1990
1991                         msleep(10);
1992                 }
1993
1994                 /* if we now have a valid request_limit, initiate a scan */
1995                 if (atomic_read(&hostdata->request_limit) > 0)
1996                         scsi_scan_host(host);
1997         }
1998
1999         dev_set_drvdata(&vdev->dev, hostdata);
2000         return 0;
2001
2002       add_srp_port_failed:
2003         scsi_remove_host(hostdata->host);
2004       add_host_failed:
2005         release_event_pool(&hostdata->pool, hostdata);
2006       init_pool_failed:
2007         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_events);
2008       kill_kthread:
2009       kthread_stop(hostdata->work_thread);
2010       init_crq_failed:
2011         unmap_persist_bufs(hostdata);
2012       persist_bufs_failed:
2013         scsi_host_put(host);
2014       scsi_host_alloc_failed:
2015         return -1;
2016 }
2017
2018 static int ibmvscsi_remove(struct vio_dev *vdev)
2019 {
2020         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
2021         unmap_persist_bufs(hostdata);
2022         release_event_pool(&hostdata->pool, hostdata);
2023         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
2024                                         max_events);
2025
2026         kthread_stop(hostdata->work_thread);
2027         srp_remove_host(hostdata->host);
2028         scsi_remove_host(hostdata->host);
2029         scsi_host_put(hostdata->host);
2030
2031         return 0;
2032 }
2033
2034 /**
2035  * ibmvscsi_resume: Resume from suspend
2036  * @dev:        device struct
2037  *
2038  * We may have lost an interrupt across suspend/resume, so kick the
2039  * interrupt handler
2040  */
2041 static int ibmvscsi_resume(struct device *dev)
2042 {
2043         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(dev);
2044         return ibmvscsi_ops->resume(hostdata);
2045 }
2046
2047 /**
2048  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
2049  * support.
2050  */
2051 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
2052         {"vscsi", "IBM,v-scsi"},
2053         { "", "" }
2054 };
2055 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
2056
2057 static struct dev_pm_ops ibmvscsi_pm_ops = {
2058         .resume = ibmvscsi_resume
2059 };
2060
2061 static struct vio_driver ibmvscsi_driver = {
2062         .id_table = ibmvscsi_device_table,
2063         .probe = ibmvscsi_probe,
2064         .remove = ibmvscsi_remove,
2065         .get_desired_dma = ibmvscsi_get_desired_dma,
2066         .driver = {
2067                 .name = "ibmvscsi",
2068                 .owner = THIS_MODULE,
2069                 .pm = &ibmvscsi_pm_ops,
2070         }
2071 };
2072
2073 static struct srp_function_template ibmvscsi_transport_functions = {
2074 };
2075
2076 int __init ibmvscsi_module_init(void)
2077 {
2078         int ret;
2079
2080         /* Ensure we have two requests to do error recovery */
2081         driver_template.can_queue = max_requests;
2082         max_events = max_requests + 2;
2083
2084         if (firmware_has_feature(FW_FEATURE_ISERIES))
2085                 ibmvscsi_ops = &iseriesvscsi_ops;
2086         else if (firmware_has_feature(FW_FEATURE_VIO))
2087                 ibmvscsi_ops = &rpavscsi_ops;
2088         else
2089                 return -ENODEV;
2090
2091         ibmvscsi_transport_template =
2092                 srp_attach_transport(&ibmvscsi_transport_functions);
2093         if (!ibmvscsi_transport_template)
2094                 return -ENOMEM;
2095
2096         ret = vio_register_driver(&ibmvscsi_driver);
2097         if (ret)
2098                 srp_release_transport(ibmvscsi_transport_template);
2099         return ret;
2100 }
2101
2102 void __exit ibmvscsi_module_exit(void)
2103 {
2104         vio_unregister_driver(&ibmvscsi_driver);
2105         srp_release_transport(ibmvscsi_transport_template);
2106 }
2107
2108 module_init(ibmvscsi_module_init);
2109 module_exit(ibmvscsi_module_exit);