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 "1.5.9"
 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 && evt->crq.format != VIOSRP_MAD_FORMAT &&
 494                            evt->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
 495                         evt->done(evt);
 496                 free_event_struct(&evt->hostdata->pool, evt);
 497                 spin_lock_irqsave(hostdata->host->host_lock, flags);
 498         }
 499         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 500 }
 501
 502 /**
 503  * ibmvscsi_reset_host - Reset the connection to the server
 504  * @hostdata:   struct ibmvscsi_host_data to reset
 505 */
 506 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
 507 {
 508         scsi_block_requests(hostdata->host);
 509         atomic_set(&hostdata->request_limit, 0);
 510
 511         purge_requests(hostdata, DID_ERROR);
 512         hostdata->reset_crq = 1;
 513         wake_up(&hostdata->work_wait_q);
 514 }
 515
 516 /**
 517  * ibmvscsi_timeout - Internal command timeout handler
 518  * @evt_struct: struct srp_event_struct that timed out
 519  *
 520  * Called when an internally generated command times out
 521 */
 522 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
 523 {
 524         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 525
 526         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
 527                 evt_struct->iu.srp.cmd.opcode);
 528
 529         ibmvscsi_reset_host(hostdata);
 530 }
 531
 532
 533 /* ------------------------------------------------------------
 534  * Routines for sending and receiving SRPs
 535  */
 536 /**
 537  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 538  * @evt_struct: evt_struct to be sent
 539  * @hostdata:   ibmvscsi_host_data of host
 540  * @timeout:    timeout in seconds - 0 means do not time command
 541  *
 542  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 543  * Note that this routine assumes that host_lock is held for synchronization
 544 */
 545 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 546                                    struct ibmvscsi_host_data *hostdata,
 547                                    unsigned long timeout)
 548 {
 549         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 550         int request_status = 0;
 551         int rc;
 552         int srp_req = 0;
 553
 554         /* If we have exhausted our request limit, just fail this request,
 555          * unless it is for a reset or abort.
 556          * Note that there are rare cases involving driver generated requests
 557          * (such as task management requests) that the mid layer may think we
 558          * can handle more requests (can_queue) when we actually can't
 559          */
 560         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
 561                 srp_req = 1;
 562                 request_status =
 563                         atomic_dec_if_positive(&hostdata->request_limit);
 564                 /* If request limit was -1 when we started, it is now even
 565                  * less than that
 566                  */
 567                 if (request_status < -1)
 568                         goto send_error;
 569                 /* Otherwise, we may have run out of requests. */
 570                 /* If request limit was 0 when we started the adapter is in the
 571                  * process of performing a login with the server adapter, or
 572                  * we may have run out of requests.
 573                  */
 574                 else if (request_status == -1 &&
 575                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
 576                         goto send_busy;
 577                 /* Abort and reset calls should make it through.
 578                  * Nothing except abort and reset should use the last two
 579                  * slots unless we had two or less to begin with.
 580                  */
 581                 else if (request_status < 2 &&
 582                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
 583                         /* In the case that we have less than two requests
 584                          * available, check the server limit as a combination
 585                          * of the request limit and the number of requests
 586                          * in-flight (the size of the send list).  If the
 587                          * server limit is greater than 2, return busy so
 588                          * that the last two are reserved for reset and abort.
 589                          */
 590                         int server_limit = request_status;
 591                         struct srp_event_struct *tmp_evt;
 592
 593                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 594                                 server_limit++;
 595                         }
 596
 597                         if (server_limit > 2)
 598                                 goto send_busy;
 599                 }
 600         }
 601
 602         /* Copy the IU into the transfer area */
 603         *evt_struct->xfer_iu = evt_struct->iu;
 604         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 605
 606         /* Add this to the sent list.  We need to do this
 607          * before we actually send
 608          * in case it comes back REALLY fast
 609          */
 610         list_add_tail(&evt_struct->list, &hostdata->sent);
 611
 612         init_timer(&evt_struct->timer);
 613         if (timeout) {
 614                 evt_struct->timer.data = (unsigned long) evt_struct;
 615                 evt_struct->timer.expires = jiffies + (timeout * HZ);
 616                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
 617                 add_timer(&evt_struct->timer);
 618         }
 619
 620         if ((rc =
 621              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 622                 list_del(&evt_struct->list);
 623                 del_timer(&evt_struct->timer);
 624
 625                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
 626                  * Firmware will send a CRQ with a transport event (0xFF) to
 627                  * tell this client what has happened to the transport.  This
 628                  * will be handled in ibmvscsi_handle_crq()
 629                  */
 630                 if (rc == H_CLOSED) {
 631                         dev_warn(hostdata->dev, "send warning. "
 632                                  "Receive queue closed, will retry.\n");
 633                         goto send_busy;
 634                 }
 635                 dev_err(hostdata->dev, "send error %d\n", rc);
 636                 if (srp_req)
 637                         atomic_inc(&hostdata->request_limit);
 638                 goto send_error;
 639         }
 640
 641         return 0;
 642
 643  send_busy:
 644         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 645
 646         free_event_struct(&hostdata->pool, evt_struct);
 647         if (srp_req && request_status != -1)
 648                 atomic_inc(&hostdata->request_limit);
 649         return SCSI_MLQUEUE_HOST_BUSY;
 650
 651  send_error:
 652         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 653
 654         if (evt_struct->cmnd != NULL) {
 655                 evt_struct->cmnd->result = DID_ERROR << 16;
 656                 evt_struct->cmnd_done(evt_struct->cmnd);
 657         } else if (evt_struct->done)
 658                 evt_struct->done(evt_struct);
 659
 660         free_event_struct(&hostdata->pool, evt_struct);
 661         return 0;
 662 }
 663
 664 /**
 665  * handle_cmd_rsp: -  Handle responses from commands
 666  * @evt_struct: srp_event_struct to be handled
 667  *
 668  * Used as a callback by when sending scsi cmds.
 669  * Gets called by ibmvscsi_handle_crq()
 670 */
 671 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 672 {
 673         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 674         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 675
 676         if (unlikely(rsp->opcode != SRP_RSP)) {
 677                 if (printk_ratelimit())
 678                         dev_warn(evt_struct->hostdata->dev,
 679                                  "bad SRP RSP type %d\n", rsp->opcode);
 680         }
 681
 682         if (cmnd) {
 683                 cmnd->result |= rsp->status;
 684                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 685                         memcpy(cmnd->sense_buffer,
 686                                rsp->data,
 687                                rsp->sense_data_len);
 688                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 689                                evt_struct,
 690                                evt_struct->hostdata->dev);
 691
 692                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 693                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
 694                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 695                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
 696         }
 697
 698         if (evt_struct->cmnd_done)
 699                 evt_struct->cmnd_done(cmnd);
 700 }
 701
 702 /**
 703  * lun_from_dev: - Returns the lun of the scsi device
 704  * @dev:        struct scsi_device
 705  *
 706 */
 707 static inline u16 lun_from_dev(struct scsi_device *dev)
 708 {
 709         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 710 }
 711
 712 /**
 713  * ibmvscsi_queue: - The queuecommand function of the scsi template
 714  * @cmd:        struct scsi_cmnd to be executed
 715  * @done:       Callback function to be called when cmd is completed
 716 */
 717 static int ibmvscsi_queuecommand_lck(struct scsi_cmnd *cmnd,
 718                                  void (*done) (struct scsi_cmnd *))
 719 {
 720         struct srp_cmd *srp_cmd;
 721         struct srp_event_struct *evt_struct;
 722         struct srp_indirect_buf *indirect;
 723         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
 724         u16 lun = lun_from_dev(cmnd->device);
 725         u8 out_fmt, in_fmt;
 726
 727         cmnd->result = (DID_OK << 16);
 728         evt_struct = get_event_struct(&hostdata->pool);
 729         if (!evt_struct)
 730                 return SCSI_MLQUEUE_HOST_BUSY;
 731
 732         /* Set up the actual SRP IU */
 733         srp_cmd = &evt_struct->iu.srp.cmd;
 734         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 735         srp_cmd->opcode = SRP_CMD;
 736         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
 737         srp_cmd->lun = ((u64) lun) << 48;
 738
 739         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 740                 if (!firmware_has_feature(FW_FEATURE_CMO))
 741                         sdev_printk(KERN_ERR, cmnd->device,
 742                                     "couldn't convert cmd to srp_cmd\n");
 743                 free_event_struct(&hostdata->pool, evt_struct);
 744                 return SCSI_MLQUEUE_HOST_BUSY;
 745         }
 746
 747         init_event_struct(evt_struct,
 748                           handle_cmd_rsp,
 749                           VIOSRP_SRP_FORMAT,
 750                           cmnd->request->timeout/HZ);
 751
 752         evt_struct->cmnd = cmnd;
 753         evt_struct->cmnd_done = done;
 754
 755         /* Fix up dma address of the buffer itself */
 756         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 757         out_fmt = srp_cmd->buf_fmt >> 4;
 758         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 759         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 760              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 761             indirect->table_desc.va == 0) {
 762                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 763                         offsetof(struct srp_cmd, add_data) +
 764                         offsetof(struct srp_indirect_buf, desc_list);
 765         }
 766
 767         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
 768 }
 769
 770 static DEF_SCSI_QCMD(ibmvscsi_queuecommand)
 771
 772 /* ------------------------------------------------------------
 773  * Routines for driver initialization
 774  */
 775
 776 /**
 777  * map_persist_bufs: - Pre-map persistent data for adapter logins
 778  * @hostdata:   ibmvscsi_host_data of host
 779  *
 780  * Map the capabilities and adapter info DMA buffers to avoid runtime failures.
 781  * Return 1 on error, 0 on success.
 782  */
 783 static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
 784 {
 785
 786         hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
 787                                              sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 788
 789         if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
 790                 dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
 791                 return 1;
 792         }
 793
 794         hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
 795                                                      &hostdata->madapter_info,
 796                                                      sizeof(hostdata->madapter_info),
 797                                                      DMA_BIDIRECTIONAL);
 798         if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
 799                 dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
 800                 dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 801                                  sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 802                 return 1;
 803         }
 804
 805         return 0;
 806 }
 807
 808 /**
 809  * unmap_persist_bufs: - Unmap persistent data needed for adapter logins
 810  * @hostdata:   ibmvscsi_host_data of host
 811  *
 812  * Unmap the capabilities and adapter info DMA buffers
 813  */
 814 static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
 815 {
 816         dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 817                          sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 818
 819         dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
 820                          sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
 821 }
 822
 823 /**
 824  * login_rsp: - Handle response to SRP login request
 825  * @evt_struct: srp_event_struct with the response
 826  *
 827  * Used as a "done" callback by when sending srp_login. Gets called
 828  * by ibmvscsi_handle_crq()
 829 */
 830 static void login_rsp(struct srp_event_struct *evt_struct)
 831 {
 832         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 833         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 834         case SRP_LOGIN_RSP:     /* it worked! */
 835                 break;
 836         case SRP_LOGIN_REJ:     /* refused! */
 837                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
 838                          evt_struct->xfer_iu->srp.login_rej.reason);
 839                 /* Login failed.  */
 840                 atomic_set(&hostdata->request_limit, -1);
 841                 return;
 842         default:
 843                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
 844                         evt_struct->xfer_iu->srp.login_rsp.opcode);
 845                 /* Login failed.  */
 846                 atomic_set(&hostdata->request_limit, -1);
 847                 return;
 848         }
 849
 850         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
 851         hostdata->client_migrated = 0;
 852
 853         /* Now we know what the real request-limit is.
 854          * This value is set rather than added to request_limit because
 855          * request_limit could have been set to -1 by this client.
 856          */
 857         atomic_set(&hostdata->request_limit,
 858                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 859
 860         /* If we had any pending I/Os, kick them */
 861         scsi_unblock_requests(hostdata->host);
 862 }
 863
 864 /**
 865  * send_srp_login: - Sends the srp login
 866  * @hostdata:   ibmvscsi_host_data of host
 867  *
 868  * Returns zero if successful.
 869 */
 870 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 871 {
 872         int rc;
 873         unsigned long flags;
 874         struct srp_login_req *login;
 875         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 876
 877         BUG_ON(!evt_struct);
 878         init_event_struct(evt_struct, login_rsp,
 879                           VIOSRP_SRP_FORMAT, login_timeout);
 880
 881         login = &evt_struct->iu.srp.login_req;
 882         memset(login, 0, sizeof(*login));
 883         login->opcode = SRP_LOGIN_REQ;
 884         login->req_it_iu_len = sizeof(union srp_iu);
 885         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 886
 887         spin_lock_irqsave(hostdata->host->host_lock, flags);
 888         /* Start out with a request limit of 0, since this is negotiated in
 889          * the login request we are just sending and login requests always
 890          * get sent by the driver regardless of request_limit.
 891          */
 892         atomic_set(&hostdata->request_limit, 0);
 893
 894         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
 895         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 896         dev_info(hostdata->dev, "sent SRP login\n");
 897         return rc;
 898 };
 899
 900 /**
 901  * capabilities_rsp: - Handle response to MAD adapter capabilities request
 902  * @evt_struct: srp_event_struct with the response
 903  *
 904  * Used as a "done" callback by when sending adapter_info.
 905  */
 906 static void capabilities_rsp(struct srp_event_struct *evt_struct)
 907 {
 908         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 909
 910         if (evt_struct->xfer_iu->mad.capabilities.common.status) {
 911                 dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
 912                         evt_struct->xfer_iu->mad.capabilities.common.status);
 913         } else {
 914                 if (hostdata->caps.migration.common.server_support != SERVER_SUPPORTS_CAP)
 915                         dev_info(hostdata->dev, "Partition migration not supported\n");
 916
 917                 if (client_reserve) {
 918                         if (hostdata->caps.reserve.common.server_support ==
 919                             SERVER_SUPPORTS_CAP)
 920                                 dev_info(hostdata->dev, "Client reserve enabled\n");
 921                         else
 922                                 dev_info(hostdata->dev, "Client reserve not supported\n");
 923                 }
 924         }
 925
 926         send_srp_login(hostdata);
 927 }
 928
 929 /**
 930  * send_mad_capabilities: - Sends the mad capabilities request
 931  *      and stores the result so it can be retrieved with
 932  * @hostdata:   ibmvscsi_host_data of host
 933  */
 934 static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
 935 {
 936         struct viosrp_capabilities *req;
 937         struct srp_event_struct *evt_struct;
 938         unsigned long flags;
 939         struct device_node *of_node = hostdata->dev->of_node;
 940         const char *location;
 941
 942         evt_struct = get_event_struct(&hostdata->pool);
 943         BUG_ON(!evt_struct);
 944
 945         init_event_struct(evt_struct, capabilities_rsp,
 946                           VIOSRP_MAD_FORMAT, info_timeout);
 947
 948         req = &evt_struct->iu.mad.capabilities;
 949         memset(req, 0, sizeof(*req));
 950
 951         hostdata->caps.flags = CAP_LIST_SUPPORTED;
 952         if (hostdata->client_migrated)
 953                 hostdata->caps.flags |= CLIENT_MIGRATED;
 954
 955         strncpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
 956                 sizeof(hostdata->caps.name));
 957         hostdata->caps.name[sizeof(hostdata->caps.name) - 1] = '\0';
 958
 959         location = of_get_property(of_node, "ibm,loc-code", NULL);
 960         location = location ? location : dev_name(hostdata->dev);
 961         strncpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
 962         hostdata->caps.loc[sizeof(hostdata->caps.loc) - 1] = '\0';
 963
 964         req->common.type = VIOSRP_CAPABILITIES_TYPE;
 965         req->buffer = hostdata->caps_addr;
 966
 967         hostdata->caps.migration.common.cap_type = MIGRATION_CAPABILITIES;
 968         hostdata->caps.migration.common.length = sizeof(hostdata->caps.migration);
 969         hostdata->caps.migration.common.server_support = SERVER_SUPPORTS_CAP;
 970         hostdata->caps.migration.ecl = 1;
 971
 972         if (client_reserve) {
 973                 hostdata->caps.reserve.common.cap_type = RESERVATION_CAPABILITIES;
 974                 hostdata->caps.reserve.common.length = sizeof(hostdata->caps.reserve);
 975                 hostdata->caps.reserve.common.server_support = SERVER_SUPPORTS_CAP;
 976                 hostdata->caps.reserve.type = CLIENT_RESERVE_SCSI_2;
 977                 req->common.length = sizeof(hostdata->caps);
 978         } else
 979                 req->common.length = sizeof(hostdata->caps) - sizeof(hostdata->caps.reserve);
 980
 981         spin_lock_irqsave(hostdata->host->host_lock, flags);
 982         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
 983                 dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
 984         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 985 };
 986
 987 /**
 988  * fast_fail_rsp: - Handle response to MAD enable fast fail
 989  * @evt_struct: srp_event_struct with the response
 990  *
 991  * Used as a "done" callback by when sending enable fast fail. Gets called
 992  * by ibmvscsi_handle_crq()
 993  */
 994 static void fast_fail_rsp(struct srp_event_struct *evt_struct)
 995 {
 996         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 997         u8 status = evt_struct->xfer_iu->mad.fast_fail.common.status;
 998
 999         if (status == VIOSRP_MAD_NOT_SUPPORTED)
1000                 dev_err(hostdata->dev, "fast_fail not supported in server\n");
1001         else if (status == VIOSRP_MAD_FAILED)
1002                 dev_err(hostdata->dev, "fast_fail request failed\n");
1003         else if (status != VIOSRP_MAD_SUCCESS)
1004                 dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
1005
1006         send_mad_capabilities(hostdata);
1007 }
1008
1009 /**
1010  * init_host - Start host initialization
1011  * @hostdata:   ibmvscsi_host_data of host
1012  *
1013  * Returns zero if successful.
1014  */
1015 static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
1016 {
1017         int rc;
1018         unsigned long flags;
1019         struct viosrp_fast_fail *fast_fail_mad;
1020         struct srp_event_struct *evt_struct;
1021
1022         if (!fast_fail) {
1023                 send_mad_capabilities(hostdata);
1024                 return 0;
1025         }
1026
1027         evt_struct = get_event_struct(&hostdata->pool);
1028         BUG_ON(!evt_struct);
1029
1030         init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
1031
1032         fast_fail_mad = &evt_struct->iu.mad.fast_fail;
1033         memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
1034         fast_fail_mad->common.type = VIOSRP_ENABLE_FAST_FAIL;
1035         fast_fail_mad->common.length = sizeof(*fast_fail_mad);
1036
1037         spin_lock_irqsave(hostdata->host->host_lock, flags);
1038         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1039         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1040         return rc;
1041 }
1042
1043 /**
1044  * adapter_info_rsp: - Handle response to MAD adapter info request
1045  * @evt_struct: srp_event_struct with the response
1046  *
1047  * Used as a "done" callback by when sending adapter_info. Gets called
1048  * by ibmvscsi_handle_crq()
1049 */
1050 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
1051 {
1052         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1053
1054         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
1055                 dev_err(hostdata->dev, "error %d getting adapter info\n",
1056                         evt_struct->xfer_iu->mad.adapter_info.common.status);
1057         } else {
1058                 dev_info(hostdata->dev, "host srp version: %s, "
1059                          "host partition %s (%d), OS %d, max io %u\n",
1060                          hostdata->madapter_info.srp_version,
1061                          hostdata->madapter_info.partition_name,
1062                          hostdata->madapter_info.partition_number,
1063                          hostdata->madapter_info.os_type,
1064                          hostdata->madapter_info.port_max_txu[0]);
1065
1066                 if (hostdata->madapter_info.port_max_txu[0])
1067                         hostdata->host->max_sectors =
1068                                 hostdata->madapter_info.port_max_txu[0] >> 9;
1069
1070                 if (hostdata->madapter_info.os_type == 3 &&
1071                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
1072                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
1073                                 hostdata->madapter_info.srp_version);
1074                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
1075                                 MAX_INDIRECT_BUFS);
1076                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
1077                 }
1078
1079                 if (hostdata->madapter_info.os_type == 3) {
1080                         enable_fast_fail(hostdata);
1081                         return;
1082                 }
1083         }
1084
1085         send_srp_login(hostdata);
1086 }
1087
1088 /**
1089  * send_mad_adapter_info: - Sends the mad adapter info request
1090  *      and stores the result so it can be retrieved with
1091  *      sysfs.  We COULD consider causing a failure if the
1092  *      returned SRP version doesn't match ours.
1093  * @hostdata:   ibmvscsi_host_data of host
1094  *
1095  * Returns zero if successful.
1096 */
1097 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
1098 {
1099         struct viosrp_adapter_info *req;
1100         struct srp_event_struct *evt_struct;
1101         unsigned long flags;
1102
1103         evt_struct = get_event_struct(&hostdata->pool);
1104         BUG_ON(!evt_struct);
1105
1106         init_event_struct(evt_struct,
1107                           adapter_info_rsp,
1108                           VIOSRP_MAD_FORMAT,
1109                           info_timeout);
1110
1111         req = &evt_struct->iu.mad.adapter_info;
1112         memset(req, 0x00, sizeof(*req));
1113
1114         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
1115         req->common.length = sizeof(hostdata->madapter_info);
1116         req->buffer = hostdata->adapter_info_addr;
1117
1118         spin_lock_irqsave(hostdata->host->host_lock, flags);
1119         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1120                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
1121         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1122 };
1123
1124 /**
1125  * init_adapter: Start virtual adapter initialization sequence
1126  *
1127  */
1128 static void init_adapter(struct ibmvscsi_host_data *hostdata)
1129 {
1130         send_mad_adapter_info(hostdata);
1131 }
1132
1133 /**
1134  * sync_completion: Signal that a synchronous command has completed
1135  * Note that after returning from this call, the evt_struct is freed.
1136  * the caller waiting on this completion shouldn't touch the evt_struct
1137  * again.
1138  */
1139 static void sync_completion(struct srp_event_struct *evt_struct)
1140 {
1141         /* copy the response back */
1142         if (evt_struct->sync_srp)
1143                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
1144
1145         complete(&evt_struct->comp);
1146 }
1147
1148 /**
1149  * ibmvscsi_abort: Abort a command...from scsi host template
1150  * send this over to the server and wait synchronously for the response
1151  */
1152 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
1153 {
1154         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1155         struct srp_tsk_mgmt *tsk_mgmt;
1156         struct srp_event_struct *evt;
1157         struct srp_event_struct *tmp_evt, *found_evt;
1158         union viosrp_iu srp_rsp;
1159         int rsp_rc;
1160         unsigned long flags;
1161         u16 lun = lun_from_dev(cmd->device);
1162         unsigned long wait_switch = 0;
1163
1164         /* First, find this command in our sent list so we can figure
1165          * out the correct tag
1166          */
1167         spin_lock_irqsave(hostdata->host->host_lock, flags);
1168         wait_switch = jiffies + (init_timeout * HZ);
1169         do {
1170                 found_evt = NULL;
1171                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1172                         if (tmp_evt->cmnd == cmd) {
1173                                 found_evt = tmp_evt;
1174                                 break;
1175                         }
1176                 }
1177
1178                 if (!found_evt) {
1179                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1180                         return SUCCESS;
1181                 }
1182
1183                 evt = get_event_struct(&hostdata->pool);
1184                 if (evt == NULL) {
1185                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1186                         sdev_printk(KERN_ERR, cmd->device,
1187                                 "failed to allocate abort event\n");
1188                         return FAILED;
1189                 }
1190
1191                 init_event_struct(evt,
1192                                   sync_completion,
1193                                   VIOSRP_SRP_FORMAT,
1194                                   abort_timeout);
1195
1196                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1197
1198                 /* Set up an abort SRP command */
1199                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1200                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1201                 tsk_mgmt->lun = ((u64) lun) << 48;
1202                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1203                 tsk_mgmt->task_tag = (u64) found_evt;
1204
1205                 evt->sync_srp = &srp_rsp;
1206
1207                 init_completion(&evt->comp);
1208                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1209
1210                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1211                         break;
1212
1213                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1214                 msleep(10);
1215                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1216         } while (time_before(jiffies, wait_switch));
1217
1218         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1219
1220         if (rsp_rc != 0) {
1221                 sdev_printk(KERN_ERR, cmd->device,
1222                             "failed to send abort() event. rc=%d\n", rsp_rc);
1223                 return FAILED;
1224         }
1225
1226         sdev_printk(KERN_INFO, cmd->device,
1227                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1228                     (((u64) lun) << 48), (u64) found_evt);
1229
1230         wait_for_completion(&evt->comp);
1231
1232         /* make sure we got a good response */
1233         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1234                 if (printk_ratelimit())
1235                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1236                                     srp_rsp.srp.rsp.opcode);
1237                 return FAILED;
1238         }
1239
1240         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1241                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1242         else
1243                 rsp_rc = srp_rsp.srp.rsp.status;
1244
1245         if (rsp_rc) {
1246                 if (printk_ratelimit())
1247                         sdev_printk(KERN_WARNING, cmd->device,
1248                                     "abort code %d for task tag 0x%llx\n",
1249                                     rsp_rc, tsk_mgmt->task_tag);
1250                 return FAILED;
1251         }
1252
1253         /* Because we dropped the spinlock above, it's possible
1254          * The event is no longer in our list.  Make sure it didn't
1255          * complete while we were aborting
1256          */
1257         spin_lock_irqsave(hostdata->host->host_lock, flags);
1258         found_evt = NULL;
1259         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1260                 if (tmp_evt->cmnd == cmd) {
1261                         found_evt = tmp_evt;
1262                         break;
1263                 }
1264         }
1265
1266         if (found_evt == NULL) {
1267                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1268                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1269                             tsk_mgmt->task_tag);
1270                 return SUCCESS;
1271         }
1272
1273         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1274                     tsk_mgmt->task_tag);
1275
1276         cmd->result = (DID_ABORT << 16);
1277         list_del(&found_evt->list);
1278         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1279                        found_evt->hostdata->dev);
1280         free_event_struct(&found_evt->hostdata->pool, found_evt);
1281         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1282         atomic_inc(&hostdata->request_limit);
1283         return SUCCESS;
1284 }
1285
1286 /**
1287  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1288  * template send this over to the server and wait synchronously for the
1289  * response
1290  */
1291 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1292 {
1293         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1294         struct srp_tsk_mgmt *tsk_mgmt;
1295         struct srp_event_struct *evt;
1296         struct srp_event_struct *tmp_evt, *pos;
1297         union viosrp_iu srp_rsp;
1298         int rsp_rc;
1299         unsigned long flags;
1300         u16 lun = lun_from_dev(cmd->device);
1301         unsigned long wait_switch = 0;
1302
1303         spin_lock_irqsave(hostdata->host->host_lock, flags);
1304         wait_switch = jiffies + (init_timeout * HZ);
1305         do {
1306                 evt = get_event_struct(&hostdata->pool);
1307                 if (evt == NULL) {
1308                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1309                         sdev_printk(KERN_ERR, cmd->device,
1310                                 "failed to allocate reset event\n");
1311                         return FAILED;
1312                 }
1313
1314                 init_event_struct(evt,
1315                                   sync_completion,
1316                                   VIOSRP_SRP_FORMAT,
1317                                   reset_timeout);
1318
1319                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1320
1321                 /* Set up a lun reset SRP command */
1322                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1323                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1324                 tsk_mgmt->lun = ((u64) lun) << 48;
1325                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1326
1327                 evt->sync_srp = &srp_rsp;
1328
1329                 init_completion(&evt->comp);
1330                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1331
1332                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1333                         break;
1334
1335                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1336                 msleep(10);
1337                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1338         } while (time_before(jiffies, wait_switch));
1339
1340         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1341
1342         if (rsp_rc != 0) {
1343                 sdev_printk(KERN_ERR, cmd->device,
1344                             "failed to send reset event. rc=%d\n", rsp_rc);
1345                 return FAILED;
1346         }
1347
1348         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1349                     (((u64) lun) << 48));
1350
1351         wait_for_completion(&evt->comp);
1352
1353         /* make sure we got a good response */
1354         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1355                 if (printk_ratelimit())
1356                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1357                                     srp_rsp.srp.rsp.opcode);
1358                 return FAILED;
1359         }
1360
1361         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1362                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1363         else
1364                 rsp_rc = srp_rsp.srp.rsp.status;
1365
1366         if (rsp_rc) {
1367                 if (printk_ratelimit())
1368                         sdev_printk(KERN_WARNING, cmd->device,
1369                                     "reset code %d for task tag 0x%llx\n",
1370                                     rsp_rc, tsk_mgmt->task_tag);
1371                 return FAILED;
1372         }
1373
1374         /* We need to find all commands for this LUN that have not yet been
1375          * responded to, and fail them with DID_RESET
1376          */
1377         spin_lock_irqsave(hostdata->host->host_lock, flags);
1378         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1379                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1380                         if (tmp_evt->cmnd)
1381                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1382                         list_del(&tmp_evt->list);
1383                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1384                                        tmp_evt->hostdata->dev);
1385                         free_event_struct(&tmp_evt->hostdata->pool,
1386                                                    tmp_evt);
1387                         atomic_inc(&hostdata->request_limit);
1388                         if (tmp_evt->cmnd_done)
1389                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1390                         else if (tmp_evt->done)
1391                                 tmp_evt->done(tmp_evt);
1392                 }
1393         }
1394         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1395         return SUCCESS;
1396 }
1397
1398 /**
1399  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1400  * @cmd:        struct scsi_cmnd having problems
1401 */
1402 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1403 {
1404         unsigned long wait_switch = 0;
1405         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1406
1407         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1408
1409         ibmvscsi_reset_host(hostdata);
1410
1411         for (wait_switch = jiffies + (init_timeout * HZ);
1412              time_before(jiffies, wait_switch) &&
1413                      atomic_read(&hostdata->request_limit) < 2;) {
1414
1415                 msleep(10);
1416         }
1417
1418         if (atomic_read(&hostdata->request_limit) <= 0)
1419                 return FAILED;
1420
1421         return SUCCESS;
1422 }
1423
1424 /**
1425  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1426  * @crq:        Command/Response queue
1427  * @hostdata:   ibmvscsi_host_data of host
1428  *
1429 */
1430 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1431                          struct ibmvscsi_host_data *hostdata)
1432 {
1433         long rc;
1434         unsigned long flags;
1435         struct srp_event_struct *evt_struct =
1436             (struct srp_event_struct *)crq->IU_data_ptr;
1437         switch (crq->valid) {
1438         case 0xC0:              /* initialization */
1439                 switch (crq->format) {
1440                 case 0x01:      /* Initialization message */
1441                         dev_info(hostdata->dev, "partner initialized\n");
1442                         /* Send back a response */
1443                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1444                                                          0xC002000000000000LL, 0)) == 0) {
1445                                 /* Now login */
1446                                 init_adapter(hostdata);
1447                         } else {
1448                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1449                         }
1450
1451                         break;
1452                 case 0x02:      /* Initialization response */
1453                         dev_info(hostdata->dev, "partner initialization complete\n");
1454
1455                         /* Now login */
1456                         init_adapter(hostdata);
1457                         break;
1458                 default:
1459                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1460                 }
1461                 return;
1462         case 0xFF:      /* Hypervisor telling us the connection is closed */
1463                 scsi_block_requests(hostdata->host);
1464                 atomic_set(&hostdata->request_limit, 0);
1465                 if (crq->format == 0x06) {
1466                         /* We need to re-setup the interpartition connection */
1467                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1468                         hostdata->client_migrated = 1;
1469                         hostdata->reenable_crq = 1;
1470                         purge_requests(hostdata, DID_REQUEUE);
1471                         wake_up(&hostdata->work_wait_q);
1472                 } else {
1473                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1474                                 crq->format);
1475                         ibmvscsi_reset_host(hostdata);
1476                 }
1477                 return;
1478         case 0x80:              /* real payload */
1479                 break;
1480         default:
1481                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1482                         crq->valid);
1483                 return;
1484         }
1485
1486         /* The only kind of payload CRQs we should get are responses to
1487          * things we send. Make sure this response is to something we
1488          * actually sent
1489          */
1490         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1491                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1492                        (void *)crq->IU_data_ptr);
1493                 return;
1494         }
1495
1496         if (atomic_read(&evt_struct->free)) {
1497                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1498                         (void *)crq->IU_data_ptr);
1499                 return;
1500         }
1501
1502         if (crq->format == VIOSRP_SRP_FORMAT)
1503                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1504                            &hostdata->request_limit);
1505
1506         del_timer(&evt_struct->timer);
1507
1508         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1509                 evt_struct->cmnd->result = DID_ERROR << 16;
1510         if (evt_struct->done)
1511                 evt_struct->done(evt_struct);
1512         else
1513                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1514
1515         /*
1516          * Lock the host_lock before messing with these structures, since we
1517          * are running in a task context
1518          */
1519         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1520         list_del(&evt_struct->list);
1521         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1522         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1523 }
1524
1525 /**
1526  * ibmvscsi_get_host_config: Send the command to the server to get host
1527  * configuration data.  The data is opaque to us.
1528  */
1529 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1530                                    unsigned char *buffer, int length)
1531 {
1532         struct viosrp_host_config *host_config;
1533         struct srp_event_struct *evt_struct;
1534         unsigned long flags;
1535         dma_addr_t addr;
1536         int rc;
1537
1538         evt_struct = get_event_struct(&hostdata->pool);
1539         if (!evt_struct) {
1540                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1541                 return -1;
1542         }
1543
1544         init_event_struct(evt_struct,
1545                           sync_completion,
1546                           VIOSRP_MAD_FORMAT,
1547                           info_timeout);
1548
1549         host_config = &evt_struct->iu.mad.host_config;
1550
1551         /* The transport length field is only 16-bit */
1552         length = min(0xffff, length);
1553
1554         /* Set up a lun reset SRP command */
1555         memset(host_config, 0x00, sizeof(*host_config));
1556         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1557         host_config->common.length = length;
1558         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1559                                                     length,
1560                                                     DMA_BIDIRECTIONAL);
1561
1562         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1563                 if (!firmware_has_feature(FW_FEATURE_CMO))
1564                         dev_err(hostdata->dev,
1565                                 "dma_mapping error getting host config\n");
1566                 free_event_struct(&hostdata->pool, evt_struct);
1567                 return -1;
1568         }
1569
1570         init_completion(&evt_struct->comp);
1571         spin_lock_irqsave(hostdata->host->host_lock, flags);
1572         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1573         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1574         if (rc == 0)
1575                 wait_for_completion(&evt_struct->comp);
1576         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1577
1578         return rc;
1579 }
1580
1581 /**
1582  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1583  * @sdev:       struct scsi_device device to configure
1584  *
1585  * Enable allow_restart for a device if it is a disk.  Adjust the
1586  * queue_depth here also as is required by the documentation for
1587  * struct scsi_host_template.
1588  */
1589 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1590 {
1591         struct Scsi_Host *shost = sdev->host;
1592         unsigned long lock_flags = 0;
1593
1594         spin_lock_irqsave(shost->host_lock, lock_flags);
1595         if (sdev->type == TYPE_DISK) {
1596                 sdev->allow_restart = 1;
1597                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1598         }
1599         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1600         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1601         return 0;
1602 }
1603
1604 /**
1605  * ibmvscsi_change_queue_depth - Change the device's queue depth
1606  * @sdev:       scsi device struct
1607  * @qdepth:     depth to set
1608  * @reason:     calling context
1609  *
1610  * Return value:
1611  *      actual depth set
1612  **/
1613 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth,
1614                                        int reason)
1615 {
1616         if (reason != SCSI_QDEPTH_DEFAULT)
1617                 return -EOPNOTSUPP;
1618
1619         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1620                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1621
1622         scsi_adjust_queue_depth(sdev, 0, qdepth);
1623         return sdev->queue_depth;
1624 }
1625
1626 /* ------------------------------------------------------------
1627  * sysfs attributes
1628  */
1629 static ssize_t show_host_vhost_loc(struct device *dev,
1630                                    struct device_attribute *attr, char *buf)
1631 {
1632         struct Scsi_Host *shost = class_to_shost(dev);
1633         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1634         int len;
1635
1636         len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
1637                        hostdata->caps.loc);
1638         return len;
1639 }
1640
1641 static struct device_attribute ibmvscsi_host_vhost_loc = {
1642         .attr = {
1643                  .name = "vhost_loc",
1644                  .mode = S_IRUGO,
1645                  },
1646         .show = show_host_vhost_loc,
1647 };
1648
1649 static ssize_t show_host_vhost_name(struct device *dev,
1650                                     struct device_attribute *attr, char *buf)
1651 {
1652         struct Scsi_Host *shost = class_to_shost(dev);
1653         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1654         int len;
1655
1656         len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
1657                        hostdata->caps.name);
1658         return len;
1659 }
1660
1661 static struct device_attribute ibmvscsi_host_vhost_name = {
1662         .attr = {
1663                  .name = "vhost_name",
1664                  .mode = S_IRUGO,
1665                  },
1666         .show = show_host_vhost_name,
1667 };
1668
1669 static ssize_t show_host_srp_version(struct device *dev,
1670                                      struct device_attribute *attr, char *buf)
1671 {
1672         struct Scsi_Host *shost = class_to_shost(dev);
1673         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1674         int len;
1675
1676         len = snprintf(buf, PAGE_SIZE, "%s\n",
1677                        hostdata->madapter_info.srp_version);
1678         return len;
1679 }
1680
1681 static struct device_attribute ibmvscsi_host_srp_version = {
1682         .attr = {
1683                  .name = "srp_version",
1684                  .mode = S_IRUGO,
1685                  },
1686         .show = show_host_srp_version,
1687 };
1688
1689 static ssize_t show_host_partition_name(struct device *dev,
1690                                         struct device_attribute *attr,
1691                                         char *buf)
1692 {
1693         struct Scsi_Host *shost = class_to_shost(dev);
1694         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1695         int len;
1696
1697         len = snprintf(buf, PAGE_SIZE, "%s\n",
1698                        hostdata->madapter_info.partition_name);
1699         return len;
1700 }
1701
1702 static struct device_attribute ibmvscsi_host_partition_name = {
1703         .attr = {
1704                  .name = "partition_name",
1705                  .mode = S_IRUGO,
1706                  },
1707         .show = show_host_partition_name,
1708 };
1709
1710 static ssize_t show_host_partition_number(struct device *dev,
1711                                           struct device_attribute *attr,
1712                                           char *buf)
1713 {
1714         struct Scsi_Host *shost = class_to_shost(dev);
1715         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1716         int len;
1717
1718         len = snprintf(buf, PAGE_SIZE, "%d\n",
1719                        hostdata->madapter_info.partition_number);
1720         return len;
1721 }
1722
1723 static struct device_attribute ibmvscsi_host_partition_number = {
1724         .attr = {
1725                  .name = "partition_number",
1726                  .mode = S_IRUGO,
1727                  },
1728         .show = show_host_partition_number,
1729 };
1730
1731 static ssize_t show_host_mad_version(struct device *dev,
1732                                      struct device_attribute *attr, char *buf)
1733 {
1734         struct Scsi_Host *shost = class_to_shost(dev);
1735         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1736         int len;
1737
1738         len = snprintf(buf, PAGE_SIZE, "%d\n",
1739                        hostdata->madapter_info.mad_version);
1740         return len;
1741 }
1742
1743 static struct device_attribute ibmvscsi_host_mad_version = {
1744         .attr = {
1745                  .name = "mad_version",
1746                  .mode = S_IRUGO,
1747                  },
1748         .show = show_host_mad_version,
1749 };
1750
1751 static ssize_t show_host_os_type(struct device *dev,
1752                                  struct device_attribute *attr, char *buf)
1753 {
1754         struct Scsi_Host *shost = class_to_shost(dev);
1755         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1756         int len;
1757
1758         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1759         return len;
1760 }
1761
1762 static struct device_attribute ibmvscsi_host_os_type = {
1763         .attr = {
1764                  .name = "os_type",
1765                  .mode = S_IRUGO,
1766                  },
1767         .show = show_host_os_type,
1768 };
1769
1770 static ssize_t show_host_config(struct device *dev,
1771                                 struct device_attribute *attr, char *buf)
1772 {
1773         struct Scsi_Host *shost = class_to_shost(dev);
1774         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1775
1776         /* returns null-terminated host config data */
1777         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1778                 return strlen(buf);
1779         else
1780                 return 0;
1781 }
1782
1783 static struct device_attribute ibmvscsi_host_config = {
1784         .attr = {
1785                  .name = "config",
1786                  .mode = S_IRUGO,
1787                  },
1788         .show = show_host_config,
1789 };
1790
1791 static struct device_attribute *ibmvscsi_attrs[] = {
1792         &ibmvscsi_host_vhost_loc,
1793         &ibmvscsi_host_vhost_name,
1794         &ibmvscsi_host_srp_version,
1795         &ibmvscsi_host_partition_name,
1796         &ibmvscsi_host_partition_number,
1797         &ibmvscsi_host_mad_version,
1798         &ibmvscsi_host_os_type,
1799         &ibmvscsi_host_config,
1800         NULL
1801 };
1802
1803 /* ------------------------------------------------------------
1804  * SCSI driver registration
1805  */
1806 static struct scsi_host_template driver_template = {
1807         .module = THIS_MODULE,
1808         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1809         .proc_name = "ibmvscsi",
1810         .queuecommand = ibmvscsi_queuecommand,
1811         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1812         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1813         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1814         .slave_configure = ibmvscsi_slave_configure,
1815         .change_queue_depth = ibmvscsi_change_queue_depth,
1816         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1817         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1818         .this_id = -1,
1819         .sg_tablesize = SG_ALL,
1820         .use_clustering = ENABLE_CLUSTERING,
1821         .shost_attrs = ibmvscsi_attrs,
1822 };
1823
1824 /**
1825  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1826  *
1827  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1828  *
1829  * Return value:
1830  *      Number of bytes of IO data the driver will need to perform well.
1831  */
1832 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1833 {
1834         /* iu_storage data allocated in initialize_event_pool */
1835         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
1836
1837         /* add io space for sg data */
1838         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1839                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1840
1841         return desired_io;
1842 }
1843
1844 static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata)
1845 {
1846         int rc;
1847         char *action = "reset";
1848
1849         if (hostdata->reset_crq) {
1850                 smp_rmb();
1851                 hostdata->reset_crq = 0;
1852
1853                 rc = ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata);
1854                 if (!rc)
1855                         rc = ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0);
1856                 vio_enable_interrupts(to_vio_dev(hostdata->dev));
1857         } else if (hostdata->reenable_crq) {
1858                 smp_rmb();
1859                 action = "enable";
1860                 rc = ibmvscsi_ops->reenable_crq_queue(&hostdata->queue, hostdata);
1861                 hostdata->reenable_crq = 0;
1862                 if (!rc)
1863                         rc = ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0);
1864         } else
1865                 return;
1866
1867         if (rc) {
1868                 atomic_set(&hostdata->request_limit, -1);
1869                 dev_err(hostdata->dev, "error after %s\n", action);
1870         }
1871
1872         scsi_unblock_requests(hostdata->host);
1873 }
1874
1875 static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata)
1876 {
1877         if (kthread_should_stop())
1878                 return 1;
1879         else if (hostdata->reset_crq) {
1880                 smp_rmb();
1881                 return 1;
1882         } else if (hostdata->reenable_crq) {
1883                 smp_rmb();
1884                 return 1;
1885         }
1886
1887         return 0;
1888 }
1889
1890 static int ibmvscsi_work(void *data)
1891 {
1892         struct ibmvscsi_host_data *hostdata = data;
1893         int rc;
1894
1895         set_user_nice(current, -20);
1896
1897         while (1) {
1898                 rc = wait_event_interruptible(hostdata->work_wait_q,
1899                                               ibmvscsi_work_to_do(hostdata));
1900
1901                 BUG_ON(rc);
1902
1903                 if (kthread_should_stop())
1904                         break;
1905
1906                 ibmvscsi_do_work(hostdata);
1907         }
1908
1909         return 0;
1910 }
1911
1912 /**
1913  * Called by bus code for each adapter
1914  */
1915 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1916 {
1917         struct ibmvscsi_host_data *hostdata;
1918         struct Scsi_Host *host;
1919         struct device *dev = &vdev->dev;
1920         struct srp_rport_identifiers ids;
1921         struct srp_rport *rport;
1922         unsigned long wait_switch = 0;
1923         int rc;
1924
1925         dev_set_drvdata(&vdev->dev, NULL);
1926
1927         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1928         if (!host) {
1929                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1930                 goto scsi_host_alloc_failed;
1931         }
1932
1933         host->transportt = ibmvscsi_transport_template;
1934         hostdata = shost_priv(host);
1935         memset(hostdata, 0x00, sizeof(*hostdata));
1936         INIT_LIST_HEAD(&hostdata->sent);
1937         init_waitqueue_head(&hostdata->work_wait_q);
1938         hostdata->host = host;
1939         hostdata->dev = dev;
1940         atomic_set(&hostdata->request_limit, -1);
1941         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1942
1943         if (map_persist_bufs(hostdata)) {
1944                 dev_err(&vdev->dev, "couldn't map persistent buffers\n");
1945                 goto persist_bufs_failed;
1946         }
1947
1948         hostdata->work_thread = kthread_run(ibmvscsi_work, hostdata, "%s_%d",
1949                                             "ibmvscsi", host->host_no);
1950
1951         if (IS_ERR(hostdata->work_thread)) {
1952                 dev_err(&vdev->dev, "couldn't initialize kthread. rc=%ld\n",
1953                         PTR_ERR(hostdata->work_thread));
1954                 goto init_crq_failed;
1955         }
1956
1957         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_events);
1958         if (rc != 0 && rc != H_RESOURCE) {
1959                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1960                 goto kill_kthread;
1961         }
1962         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
1963                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1964                 goto init_pool_failed;
1965         }
1966
1967         host->max_lun = 8;
1968         host->max_id = max_id;
1969         host->max_channel = max_channel;
1970         host->max_cmd_len = 16;
1971
1972         if (scsi_add_host(hostdata->host, hostdata->dev))
1973                 goto add_host_failed;
1974
1975         /* we don't have a proper target_port_id so let's use the fake one */
1976         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1977                sizeof(ids.port_id));
1978         ids.roles = SRP_RPORT_ROLE_TARGET;
1979         rport = srp_rport_add(host, &ids);
1980         if (IS_ERR(rport))
1981                 goto add_srp_port_failed;
1982
1983         /* Try to send an initialization message.  Note that this is allowed
1984          * to fail if the other end is not acive.  In that case we don't
1985          * want to scan
1986          */
1987         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1988             || rc == H_RESOURCE) {
1989                 /*
1990                  * Wait around max init_timeout secs for the adapter to finish
1991                  * initializing. When we are done initializing, we will have a
1992                  * valid request_limit.  We don't want Linux scanning before
1993                  * we are ready.
1994                  */
1995                 for (wait_switch = jiffies + (init_timeout * HZ);
1996                      time_before(jiffies, wait_switch) &&
1997                      atomic_read(&hostdata->request_limit) < 2;) {
1998
1999                         msleep(10);
2000                 }
2001
2002                 /* if we now have a valid request_limit, initiate a scan */
2003                 if (atomic_read(&hostdata->request_limit) > 0)
2004                         scsi_scan_host(host);
2005         }
2006
2007         dev_set_drvdata(&vdev->dev, hostdata);
2008         return 0;
2009
2010       add_srp_port_failed:
2011         scsi_remove_host(hostdata->host);
2012       add_host_failed:
2013         release_event_pool(&hostdata->pool, hostdata);
2014       init_pool_failed:
2015         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_events);
2016       kill_kthread:
2017       kthread_stop(hostdata->work_thread);
2018       init_crq_failed:
2019         unmap_persist_bufs(hostdata);
2020       persist_bufs_failed:
2021         scsi_host_put(host);
2022       scsi_host_alloc_failed:
2023         return -1;
2024 }
2025
2026 static int ibmvscsi_remove(struct vio_dev *vdev)
2027 {
2028         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
2029         unmap_persist_bufs(hostdata);
2030         release_event_pool(&hostdata->pool, hostdata);
2031         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
2032                                         max_events);
2033
2034         kthread_stop(hostdata->work_thread);
2035         srp_remove_host(hostdata->host);
2036         scsi_remove_host(hostdata->host);
2037         scsi_host_put(hostdata->host);
2038
2039         return 0;
2040 }
2041
2042 /**
2043  * ibmvscsi_resume: Resume from suspend
2044  * @dev:        device struct
2045  *
2046  * We may have lost an interrupt across suspend/resume, so kick the
2047  * interrupt handler
2048  */
2049 static int ibmvscsi_resume(struct device *dev)
2050 {
2051         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(dev);
2052         return ibmvscsi_ops->resume(hostdata);
2053 }
2054
2055 /**
2056  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
2057  * support.
2058  */
2059 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
2060         {"vscsi", "IBM,v-scsi"},
2061         { "", "" }
2062 };
2063 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
2064
2065 static struct dev_pm_ops ibmvscsi_pm_ops = {
2066         .resume = ibmvscsi_resume
2067 };
2068
2069 static struct vio_driver ibmvscsi_driver = {
2070         .id_table = ibmvscsi_device_table,
2071         .probe = ibmvscsi_probe,
2072         .remove = ibmvscsi_remove,
2073         .get_desired_dma = ibmvscsi_get_desired_dma,
2074         .driver = {
2075                 .name = "ibmvscsi",
2076                 .owner = THIS_MODULE,
2077                 .pm = &ibmvscsi_pm_ops,
2078         }
2079 };
2080
2081 static struct srp_function_template ibmvscsi_transport_functions = {
2082 };
2083
2084 int __init ibmvscsi_module_init(void)
2085 {
2086         int ret;
2087
2088         /* Ensure we have two requests to do error recovery */
2089         driver_template.can_queue = max_requests;
2090         max_events = max_requests + 2;
2091
2092         if (firmware_has_feature(FW_FEATURE_ISERIES))
2093                 ibmvscsi_ops = &iseriesvscsi_ops;
2094         else if (firmware_has_feature(FW_FEATURE_VIO))
2095                 ibmvscsi_ops = &rpavscsi_ops;
2096         else
2097                 return -ENODEV;
2098
2099         ibmvscsi_transport_template =
2100                 srp_attach_transport(&ibmvscsi_transport_functions);
2101         if (!ibmvscsi_transport_template)
2102                 return -ENOMEM;
2103
2104         ret = vio_register_driver(&ibmvscsi_driver);
2105         if (ret)
2106                 srp_release_transport(ibmvscsi_transport_template);
2107         return ret;
2108 }
2109
2110 void __exit ibmvscsi_module_exit(void)
2111 {
2112         vio_unregister_driver(&ibmvscsi_driver);
2113         srp_release_transport(ibmvscsi_transport_template);
2114 }
2115
2116 module_init(ibmvscsi_module_init);
2117 module_exit(ibmvscsi_module_exit);