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