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