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-robbin fashion,
  44  * turns on the high order bit of the message (the valid bit), and
  45  * generates an interrupt to the receiver (if interrupts are turned on.)
  46  * The receiver just turns off the valid bit when they have copied out
  47  * the message.
  48  *
  49  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
  50  * (IU) (as defined in the T10 standard available at www.t10.org), gets
  51  * a DMA address for the message, and sends it to the server as the
  52  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
  53  * including doing any additional data transfers.  When it is done, it
  54  * DMAs the SRP response back to the same address as the request came from,
  55  * and sends a CRQ message back to inform the client that the request has
  56  * completed.
  57  *
  58  * Note that some of the underlying infrastructure is different between
  59  * machines conforming to the "RS/6000 Platform Architecture" (RPA) and
  60  * the older iSeries hypervisor models.  To support both, some low level
  61  * routines have been broken out into rpa_vscsi.c and iseries_vscsi.c.
  62  * The Makefile should pick one, not two, not zero, of these.
  63  *
  64  * TODO: This is currently pretty tied to the IBM i/pSeries hypervisor
  65  * interfaces.  It would be really nice to abstract this above an RDMA
  66  * layer.
  67  */
  68
  69 #include <linux/module.h>
  70 #include <linux/moduleparam.h>
  71 #include <linux/dma-mapping.h>
  72 #include <linux/delay.h>
  73 #include <asm/vio.h>
  74 #include <scsi/scsi.h>
  75 #include <scsi/scsi_cmnd.h>
  76 #include <scsi/scsi_host.h>
  77 #include <scsi/scsi_device.h>
  78 #include "ibmvscsi.h"
  79
  80 /* The values below are somewhat arbitrary default values, but
  81  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
  82  * Note that there are 3 bits of channel value, 6 bits of id, and
  83  * 5 bits of LUN.
  84  */
  85 static int max_id = 64;
  86 static int max_channel = 3;
  87 static int init_timeout = 5;
  88 static int max_requests = 50;
  89
  90 #define IBMVSCSI_VERSION "1.5.8"
  91
  92 MODULE_DESCRIPTION("IBM Virtual SCSI");
  93 MODULE_AUTHOR("Dave Boutcher");
  94 MODULE_LICENSE("GPL");
  95 MODULE_VERSION(IBMVSCSI_VERSION);
  96
  97 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
  98 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
  99 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
 100 MODULE_PARM_DESC(max_channel, "Largest channel value");
 101 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
 102 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
 103 module_param_named(max_requests, max_requests, int, S_IRUGO | S_IWUSR);
 104 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
 105
 106 /* ------------------------------------------------------------
 107  * Routines for the event pool and event structs
 108  */
 109 /**
 110  * initialize_event_pool: - Allocates and initializes the event pool for a host
 111  * @pool:       event_pool to be initialized
 112  * @size:       Number of events in pool
 113  * @hostdata:   ibmvscsi_host_data who owns the event pool
 114  *
 115  * Returns zero on success.
 116 */
 117 static int initialize_event_pool(struct event_pool *pool,
 118                                  int size, struct ibmvscsi_host_data *hostdata)
 119 {
 120         int i;
 121
 122         pool->size = size;
 123         pool->next = 0;
 124         pool->events = kmalloc(pool->size * sizeof(*pool->events), GFP_KERNEL);
 125         if (!pool->events)
 126                 return -ENOMEM;
 127         memset(pool->events, 0x00, pool->size * sizeof(*pool->events));
 128
 129         pool->iu_storage =
 130             dma_alloc_coherent(hostdata->dev,
 131                                pool->size * sizeof(*pool->iu_storage),
 132                                &pool->iu_token, 0);
 133         if (!pool->iu_storage) {
 134                 kfree(pool->events);
 135                 return -ENOMEM;
 136         }
 137
 138         for (i = 0; i < pool->size; ++i) {
 139                 struct srp_event_struct *evt = &pool->events[i];
 140                 memset(&evt->crq, 0x00, sizeof(evt->crq));
 141                 atomic_set(&evt->free, 1);
 142                 evt->crq.valid = 0x80;
 143                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
 144                 evt->crq.IU_data_ptr = pool->iu_token +
 145                         sizeof(*evt->xfer_iu) * i;
 146                 evt->xfer_iu = pool->iu_storage + i;
 147                 evt->hostdata = hostdata;
 148                 evt->ext_list = NULL;
 149                 evt->ext_list_token = 0;
 150         }
 151
 152         return 0;
 153 }
 154
 155 /**
 156  * release_event_pool: - Frees memory of an event pool of a host
 157  * @pool:       event_pool to be released
 158  * @hostdata:   ibmvscsi_host_data who owns the even pool
 159  *
 160  * Returns zero on success.
 161 */
 162 static void release_event_pool(struct event_pool *pool,
 163                                struct ibmvscsi_host_data *hostdata)
 164 {
 165         int i, in_use = 0;
 166         for (i = 0; i < pool->size; ++i) {
 167                 if (atomic_read(&pool->events[i].free) != 1)
 168                         ++in_use;
 169                 if (pool->events[i].ext_list) {
 170                         dma_free_coherent(hostdata->dev,
 171                                   SG_ALL * sizeof(struct srp_direct_buf),
 172                                   pool->events[i].ext_list,
 173                                   pool->events[i].ext_list_token);
 174                 }
 175         }
 176         if (in_use)
 177                 printk(KERN_WARNING
 178                        "ibmvscsi: releasing event pool with %d "
 179                        "events still in use?\n", in_use);
 180         kfree(pool->events);
 181         dma_free_coherent(hostdata->dev,
 182                           pool->size * sizeof(*pool->iu_storage),
 183                           pool->iu_storage, pool->iu_token);
 184 }
 185
 186 /**
 187  * valid_event_struct: - Determines if event is valid.
 188  * @pool:       event_pool that contains the event
 189  * @evt:        srp_event_struct to be checked for validity
 190  *
 191  * Returns zero if event is invalid, one otherwise.
 192 */
 193 static int valid_event_struct(struct event_pool *pool,
 194                                 struct srp_event_struct *evt)
 195 {
 196         int index = evt - pool->events;
 197         if (index < 0 || index >= pool->size)   /* outside of bounds */
 198                 return 0;
 199         if (evt != pool->events + index)        /* unaligned */
 200                 return 0;
 201         return 1;
 202 }
 203
 204 /**
 205  * ibmvscsi_free-event_struct: - Changes status of event to "free"
 206  * @pool:       event_pool that contains the event
 207  * @evt:        srp_event_struct to be modified
 208  *
 209 */
 210 static void free_event_struct(struct event_pool *pool,
 211                                        struct srp_event_struct *evt)
 212 {
 213         if (!valid_event_struct(pool, evt)) {
 214                 printk(KERN_ERR
 215                        "ibmvscsi: Freeing invalid event_struct %p "
 216                        "(not in pool %p)\n", evt, pool->events);
 217                 return;
 218         }
 219         if (atomic_inc_return(&evt->free) != 1) {
 220                 printk(KERN_ERR
 221                        "ibmvscsi: Freeing event_struct %p "
 222                        "which is not in use!\n", evt);
 223                 return;
 224         }
 225 }
 226
 227 /**
 228  * get_evt_struct: - Gets the next free event in pool
 229  * @pool:       event_pool that contains the events to be searched
 230  *
 231  * Returns the next event in "free" state, and NULL if none are free.
 232  * Note that no synchronization is done here, we assume the host_lock
 233  * will syncrhonze things.
 234 */
 235 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
 236 {
 237         int i;
 238         int poolsize = pool->size;
 239         int offset = pool->next;
 240
 241         for (i = 0; i < poolsize; i++) {
 242                 offset = (offset + 1) % poolsize;
 243                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
 244                         pool->next = offset;
 245                         return &pool->events[offset];
 246                 }
 247         }
 248
 249         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
 250         return NULL;
 251 }
 252
 253 /**
 254  * init_event_struct: Initialize fields in an event struct that are always
 255  *                    required.
 256  * @evt:        The event
 257  * @done:       Routine to call when the event is responded to
 258  * @format:     SRP or MAD format
 259  * @timeout:    timeout value set in the CRQ
 260  */
 261 static void init_event_struct(struct srp_event_struct *evt_struct,
 262                               void (*done) (struct srp_event_struct *),
 263                               u8 format,
 264                               int timeout)
 265 {
 266         evt_struct->cmnd = NULL;
 267         evt_struct->cmnd_done = NULL;
 268         evt_struct->sync_srp = NULL;
 269         evt_struct->crq.format = format;
 270         evt_struct->crq.timeout = timeout;
 271         evt_struct->done = done;
 272 }
 273
 274 /* ------------------------------------------------------------
 275  * Routines for receiving SCSI responses from the hosting partition
 276  */
 277
 278 /**
 279  * set_srp_direction: Set the fields in the srp related to data
 280  *     direction and number of buffers based on the direction in
 281  *     the scsi_cmnd and the number of buffers
 282  */
 283 static void set_srp_direction(struct scsi_cmnd *cmd,
 284                               struct srp_cmd *srp_cmd,
 285                               int numbuf)
 286 {
 287         u8 fmt;
 288
 289         if (numbuf == 0)
 290                 return;
 291
 292         if (numbuf == 1)
 293                 fmt = SRP_DATA_DESC_DIRECT;
 294         else {
 295                 fmt = SRP_DATA_DESC_INDIRECT;
 296                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
 297
 298                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
 299                         srp_cmd->data_out_desc_cnt = numbuf;
 300                 else
 301                         srp_cmd->data_in_desc_cnt = numbuf;
 302         }
 303
 304         if (cmd->sc_data_direction == DMA_TO_DEVICE)
 305                 srp_cmd->buf_fmt = fmt << 4;
 306         else
 307                 srp_cmd->buf_fmt = fmt;
 308 }
 309
 310 static void unmap_sg_list(int num_entries,
 311                 struct device *dev,
 312                 struct srp_direct_buf *md)
 313 {
 314         int i;
 315
 316         for (i = 0; i < num_entries; ++i)
 317                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
 318 }
 319
 320 /**
 321  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
 322  * @cmd:        srp_cmd whose additional_data member will be unmapped
 323  * @dev:        device for which the memory is mapped
 324  *
 325 */
 326 static void unmap_cmd_data(struct srp_cmd *cmd,
 327                            struct srp_event_struct *evt_struct,
 328                            struct device *dev)
 329 {
 330         u8 out_fmt, in_fmt;
 331
 332         out_fmt = cmd->buf_fmt >> 4;
 333         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
 334
 335         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
 336                 return;
 337         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
 338                  in_fmt == SRP_DATA_DESC_DIRECT) {
 339                 struct srp_direct_buf *data =
 340                         (struct srp_direct_buf *) cmd->add_data;
 341                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
 342         } else {
 343                 struct srp_indirect_buf *indirect =
 344                         (struct srp_indirect_buf *) cmd->add_data;
 345                 int num_mapped = indirect->table_desc.len /
 346                         sizeof(struct srp_direct_buf);
 347
 348                 if (num_mapped <= MAX_INDIRECT_BUFS) {
 349                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
 350                         return;
 351                 }
 352
 353                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
 354         }
 355 }
 356
 357 static int map_sg_list(int num_entries,
 358                        struct scatterlist *sg,
 359                        struct srp_direct_buf *md)
 360 {
 361         int i;
 362         u64 total_length = 0;
 363
 364         for (i = 0; i < num_entries; ++i) {
 365                 struct srp_direct_buf *descr = md + i;
 366                 struct scatterlist *sg_entry = &sg[i];
 367                 descr->va = sg_dma_address(sg_entry);
 368                 descr->len = sg_dma_len(sg_entry);
 369                 descr->key = 0;
 370                 total_length += sg_dma_len(sg_entry);
 371         }
 372         return total_length;
 373 }
 374
 375 /**
 376  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
 377  * @cmd:        Scsi_Cmnd with the scatterlist
 378  * @srp_cmd:    srp_cmd that contains the memory descriptor
 379  * @dev:        device for which to map dma memory
 380  *
 381  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 382  * Returns 1 on success.
 383 */
 384 static int map_sg_data(struct scsi_cmnd *cmd,
 385                        struct srp_event_struct *evt_struct,
 386                        struct srp_cmd *srp_cmd, struct device *dev)
 387 {
 388
 389         int sg_mapped;
 390         u64 total_length = 0;
 391         struct scatterlist *sg = cmd->request_buffer;
 392         struct srp_direct_buf *data =
 393                 (struct srp_direct_buf *) srp_cmd->add_data;
 394         struct srp_indirect_buf *indirect =
 395                 (struct srp_indirect_buf *) data;
 396
 397         sg_mapped = dma_map_sg(dev, sg, cmd->use_sg, DMA_BIDIRECTIONAL);
 398
 399         if (sg_mapped == 0)
 400                 return 0;
 401
 402         set_srp_direction(cmd, srp_cmd, sg_mapped);
 403
 404         /* special case; we can use a single direct descriptor */
 405         if (sg_mapped == 1) {
 406                 data->va = sg_dma_address(&sg[0]);
 407                 data->len = sg_dma_len(&sg[0]);
 408                 data->key = 0;
 409                 return 1;
 410         }
 411
 412         if (sg_mapped > SG_ALL) {
 413                 printk(KERN_ERR
 414                        "ibmvscsi: More than %d mapped sg entries, got %d\n",
 415                        SG_ALL, sg_mapped);
 416                 return 0;
 417         }
 418
 419         indirect->table_desc.va = 0;
 420         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
 421         indirect->table_desc.key = 0;
 422
 423         if (sg_mapped <= MAX_INDIRECT_BUFS) {
 424                 total_length = map_sg_list(sg_mapped, sg,
 425                                            &indirect->desc_list[0]);
 426                 indirect->len = total_length;
 427                 return 1;
 428         }
 429
 430         /* get indirect table */
 431         if (!evt_struct->ext_list) {
 432                 evt_struct->ext_list = (struct srp_direct_buf *)
 433                         dma_alloc_coherent(dev,
 434                                            SG_ALL * sizeof(struct srp_direct_buf),
 435                                            &evt_struct->ext_list_token, 0);
 436                 if (!evt_struct->ext_list) {
 437                         printk(KERN_ERR
 438                                "ibmvscsi: Can't allocate memory for indirect table\n");
 439                         return 0;
 440
 441                 }
 442         }
 443
 444         total_length = map_sg_list(sg_mapped, sg, evt_struct->ext_list);
 445
 446         indirect->len = total_length;
 447         indirect->table_desc.va = evt_struct->ext_list_token;
 448         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
 449         memcpy(indirect->desc_list, evt_struct->ext_list,
 450                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
 451
 452         return 1;
 453 }
 454
 455 /**
 456  * map_single_data: - Maps memory and initializes memory decriptor fields
 457  * @cmd:        struct scsi_cmnd with the memory to be mapped
 458  * @srp_cmd:    srp_cmd that contains the memory descriptor
 459  * @dev:        device for which to map dma memory
 460  *
 461  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 462  * Returns 1 on success.
 463 */
 464 static int map_single_data(struct scsi_cmnd *cmd,
 465                            struct srp_cmd *srp_cmd, struct device *dev)
 466 {
 467         struct srp_direct_buf *data =
 468                 (struct srp_direct_buf *) srp_cmd->add_data;
 469
 470         data->va =
 471                 dma_map_single(dev, cmd->request_buffer,
 472                                cmd->request_bufflen,
 473                                DMA_BIDIRECTIONAL);
 474         if (dma_mapping_error(data->va)) {
 475                 printk(KERN_ERR
 476                        "ibmvscsi: Unable to map request_buffer for command!\n");
 477                 return 0;
 478         }
 479         data->len = cmd->request_bufflen;
 480         data->key = 0;
 481
 482         set_srp_direction(cmd, srp_cmd, 1);
 483
 484         return 1;
 485 }
 486
 487 /**
 488  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
 489  * @cmd:        struct scsi_cmnd with the memory to be mapped
 490  * @srp_cmd:    srp_cmd that contains the memory descriptor
 491  * @dev:        dma device for which to map dma memory
 492  *
 493  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
 494  * Returns 1 on success.
 495 */
 496 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
 497                                 struct srp_event_struct *evt_struct,
 498                                 struct srp_cmd *srp_cmd, struct device *dev)
 499 {
 500         switch (cmd->sc_data_direction) {
 501         case DMA_FROM_DEVICE:
 502         case DMA_TO_DEVICE:
 503                 break;
 504         case DMA_NONE:
 505                 return 1;
 506         case DMA_BIDIRECTIONAL:
 507                 printk(KERN_ERR
 508                        "ibmvscsi: Can't map DMA_BIDIRECTIONAL to read/write\n");
 509                 return 0;
 510         default:
 511                 printk(KERN_ERR
 512                        "ibmvscsi: Unknown data direction 0x%02x; can't map!\n",
 513                        cmd->sc_data_direction);
 514                 return 0;
 515         }
 516
 517         if (!cmd->request_buffer)
 518                 return 1;
 519         if (cmd->use_sg)
 520                 return map_sg_data(cmd, evt_struct, srp_cmd, dev);
 521         return map_single_data(cmd, srp_cmd, dev);
 522 }
 523
 524 /* ------------------------------------------------------------
 525  * Routines for sending and receiving SRPs
 526  */
 527 /**
 528  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 529  * @evt_struct: evt_struct to be sent
 530  * @hostdata:   ibmvscsi_host_data of host
 531  *
 532  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 533  * Note that this routine assumes that host_lock is held for synchronization
 534 */
 535 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 536                                    struct ibmvscsi_host_data *hostdata)
 537 {
 538         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 539         int rc;
 540
 541         /* If we have exhausted our request limit, just fail this request.
 542          * Note that there are rare cases involving driver generated requests
 543          * (such as task management requests) that the mid layer may think we
 544          * can handle more requests (can_queue) when we actually can't
 545          */
 546         if ((evt_struct->crq.format == VIOSRP_SRP_FORMAT) &&
 547             (atomic_dec_if_positive(&hostdata->request_limit) < 0))
 548                 goto send_error;
 549
 550         /* Copy the IU into the transfer area */
 551         *evt_struct->xfer_iu = evt_struct->iu;
 552         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 553
 554         /* Add this to the sent list.  We need to do this
 555          * before we actually send
 556          * in case it comes back REALLY fast
 557          */
 558         list_add_tail(&evt_struct->list, &hostdata->sent);
 559
 560         if ((rc =
 561              ibmvscsi_send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 562                 list_del(&evt_struct->list);
 563
 564                 printk(KERN_ERR "ibmvscsi: send error %d\n",
 565                        rc);
 566                 goto send_error;
 567         }
 568
 569         return 0;
 570
 571  send_error:
 572         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 573
 574         free_event_struct(&hostdata->pool, evt_struct);
 575         return SCSI_MLQUEUE_HOST_BUSY;
 576 }
 577
 578 /**
 579  * handle_cmd_rsp: -  Handle responses from commands
 580  * @evt_struct: srp_event_struct to be handled
 581  *
 582  * Used as a callback by when sending scsi cmds.
 583  * Gets called by ibmvscsi_handle_crq()
 584 */
 585 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 586 {
 587         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 588         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 589
 590         if (unlikely(rsp->opcode != SRP_RSP)) {
 591                 if (printk_ratelimit())
 592                         printk(KERN_WARNING
 593                                "ibmvscsi: bad SRP RSP type %d\n",
 594                                rsp->opcode);
 595         }
 596
 597         if (cmnd) {
 598                 cmnd->result = rsp->status;
 599                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 600                         memcpy(cmnd->sense_buffer,
 601                                rsp->data,
 602                                rsp->sense_data_len);
 603                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 604                                evt_struct,
 605                                evt_struct->hostdata->dev);
 606
 607                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 608                         cmnd->resid = rsp->data_out_res_cnt;
 609                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 610                         cmnd->resid = rsp->data_in_res_cnt;
 611         }
 612
 613         if (evt_struct->cmnd_done)
 614                 evt_struct->cmnd_done(cmnd);
 615 }
 616
 617 /**
 618  * lun_from_dev: - Returns the lun of the scsi device
 619  * @dev:        struct scsi_device
 620  *
 621 */
 622 static inline u16 lun_from_dev(struct scsi_device *dev)
 623 {
 624         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 625 }
 626
 627 /**
 628  * ibmvscsi_queue: - The queuecommand function of the scsi template
 629  * @cmd:        struct scsi_cmnd to be executed
 630  * @done:       Callback function to be called when cmd is completed
 631 */
 632 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
 633                                  void (*done) (struct scsi_cmnd *))
 634 {
 635         struct srp_cmd *srp_cmd;
 636         struct srp_event_struct *evt_struct;
 637         struct srp_indirect_buf *indirect;
 638         struct ibmvscsi_host_data *hostdata =
 639                 (struct ibmvscsi_host_data *)&cmnd->device->host->hostdata;
 640         u16 lun = lun_from_dev(cmnd->device);
 641         u8 out_fmt, in_fmt;
 642
 643         evt_struct = get_event_struct(&hostdata->pool);
 644         if (!evt_struct)
 645                 return SCSI_MLQUEUE_HOST_BUSY;
 646
 647         /* Set up the actual SRP IU */
 648         srp_cmd = &evt_struct->iu.srp.cmd;
 649         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 650         srp_cmd->opcode = SRP_CMD;
 651         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(cmnd->cmnd));
 652         srp_cmd->lun = ((u64) lun) << 48;
 653
 654         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 655                 printk(KERN_ERR "ibmvscsi: couldn't convert cmd to srp_cmd\n");
 656                 free_event_struct(&hostdata->pool, evt_struct);
 657                 return SCSI_MLQUEUE_HOST_BUSY;
 658         }
 659
 660         init_event_struct(evt_struct,
 661                           handle_cmd_rsp,
 662                           VIOSRP_SRP_FORMAT,
 663                           cmnd->timeout_per_command/HZ);
 664
 665         evt_struct->cmnd = cmnd;
 666         evt_struct->cmnd_done = done;
 667
 668         /* Fix up dma address of the buffer itself */
 669         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 670         out_fmt = srp_cmd->buf_fmt >> 4;
 671         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 672         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 673              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 674             indirect->table_desc.va == 0) {
 675                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 676                         offsetof(struct srp_cmd, add_data) +
 677                         offsetof(struct srp_indirect_buf, desc_list);
 678         }
 679
 680         return ibmvscsi_send_srp_event(evt_struct, hostdata);
 681 }
 682
 683 /* ------------------------------------------------------------
 684  * Routines for driver initialization
 685  */
 686 /**
 687  * adapter_info_rsp: - Handle response to MAD adapter info request
 688  * @evt_struct: srp_event_struct with the response
 689  *
 690  * Used as a "done" callback by when sending adapter_info. Gets called
 691  * by ibmvscsi_handle_crq()
 692 */
 693 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
 694 {
 695         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 696         dma_unmap_single(hostdata->dev,
 697                          evt_struct->iu.mad.adapter_info.buffer,
 698                          evt_struct->iu.mad.adapter_info.common.length,
 699                          DMA_BIDIRECTIONAL);
 700
 701         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
 702                 printk("ibmvscsi: error %d getting adapter info\n",
 703                        evt_struct->xfer_iu->mad.adapter_info.common.status);
 704         } else {
 705                 printk("ibmvscsi: host srp version: %s, "
 706                        "host partition %s (%d), OS %d, max io %u\n",
 707                        hostdata->madapter_info.srp_version,
 708                        hostdata->madapter_info.partition_name,
 709                        hostdata->madapter_info.partition_number,
 710                        hostdata->madapter_info.os_type,
 711                        hostdata->madapter_info.port_max_txu[0]);
 712
 713                 if (hostdata->madapter_info.port_max_txu[0])
 714                         hostdata->host->max_sectors =
 715                                 hostdata->madapter_info.port_max_txu[0] >> 9;
 716
 717                 if (hostdata->madapter_info.os_type == 3 &&
 718                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
 719                         printk("ibmvscsi: host (Ver. %s) doesn't support large"
 720                                "transfers\n",
 721                                hostdata->madapter_info.srp_version);
 722                         printk("ibmvscsi: limiting scatterlists to %d\n",
 723                                MAX_INDIRECT_BUFS);
 724                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
 725                 }
 726         }
 727 }
 728
 729 /**
 730  * send_mad_adapter_info: - Sends the mad adapter info request
 731  *      and stores the result so it can be retrieved with
 732  *      sysfs.  We COULD consider causing a failure if the
 733  *      returned SRP version doesn't match ours.
 734  * @hostdata:   ibmvscsi_host_data of host
 735  *
 736  * Returns zero if successful.
 737 */
 738 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
 739 {
 740         struct viosrp_adapter_info *req;
 741         struct srp_event_struct *evt_struct;
 742         dma_addr_t addr;
 743
 744         evt_struct = get_event_struct(&hostdata->pool);
 745         if (!evt_struct) {
 746                 printk(KERN_ERR "ibmvscsi: couldn't allocate an event "
 747                        "for ADAPTER_INFO_REQ!\n");
 748                 return;
 749         }
 750
 751         init_event_struct(evt_struct,
 752                           adapter_info_rsp,
 753                           VIOSRP_MAD_FORMAT,
 754                           init_timeout * HZ);
 755
 756         req = &evt_struct->iu.mad.adapter_info;
 757         memset(req, 0x00, sizeof(*req));
 758
 759         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
 760         req->common.length = sizeof(hostdata->madapter_info);
 761         req->buffer = addr = dma_map_single(hostdata->dev,
 762                                             &hostdata->madapter_info,
 763                                             sizeof(hostdata->madapter_info),
 764                                             DMA_BIDIRECTIONAL);
 765
 766         if (dma_mapping_error(req->buffer)) {
 767                 printk(KERN_ERR
 768                        "ibmvscsi: Unable to map request_buffer "
 769                        "for adapter_info!\n");
 770                 free_event_struct(&hostdata->pool, evt_struct);
 771                 return;
 772         }
 773
 774         if (ibmvscsi_send_srp_event(evt_struct, hostdata)) {
 775                 printk(KERN_ERR "ibmvscsi: couldn't send ADAPTER_INFO_REQ!\n");
 776                 dma_unmap_single(hostdata->dev,
 777                                  addr,
 778                                  sizeof(hostdata->madapter_info),
 779                                  DMA_BIDIRECTIONAL);
 780         }
 781 };
 782
 783 /**
 784  * login_rsp: - Handle response to SRP login request
 785  * @evt_struct: srp_event_struct with the response
 786  *
 787  * Used as a "done" callback by when sending srp_login. Gets called
 788  * by ibmvscsi_handle_crq()
 789 */
 790 static void login_rsp(struct srp_event_struct *evt_struct)
 791 {
 792         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 793         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 794         case SRP_LOGIN_RSP:     /* it worked! */
 795                 break;
 796         case SRP_LOGIN_REJ:     /* refused! */
 797                 printk(KERN_INFO "ibmvscsi: SRP_LOGIN_REJ reason %u\n",
 798                        evt_struct->xfer_iu->srp.login_rej.reason);
 799                 /* Login failed.  */
 800                 atomic_set(&hostdata->request_limit, -1);
 801                 return;
 802         default:
 803                 printk(KERN_ERR
 804                        "ibmvscsi: Invalid login response typecode 0x%02x!\n",
 805                        evt_struct->xfer_iu->srp.login_rsp.opcode);
 806                 /* Login failed.  */
 807                 atomic_set(&hostdata->request_limit, -1);
 808                 return;
 809         }
 810
 811         printk(KERN_INFO "ibmvscsi: SRP_LOGIN succeeded\n");
 812
 813         if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta >
 814             (max_requests - 2))
 815                 evt_struct->xfer_iu->srp.login_rsp.req_lim_delta =
 816                     max_requests - 2;
 817
 818         /* Now we know what the real request-limit is */
 819         atomic_set(&hostdata->request_limit,
 820                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 821
 822         hostdata->host->can_queue =
 823             evt_struct->xfer_iu->srp.login_rsp.req_lim_delta - 2;
 824
 825         if (hostdata->host->can_queue < 1) {
 826                 printk(KERN_ERR "ibmvscsi: Invalid request_limit_delta\n");
 827                 return;
 828         }
 829
 830         /* If we had any pending I/Os, kick them */
 831         scsi_unblock_requests(hostdata->host);
 832
 833         send_mad_adapter_info(hostdata);
 834         return;
 835 }
 836
 837 /**
 838  * send_srp_login: - Sends the srp login
 839  * @hostdata:   ibmvscsi_host_data of host
 840  *
 841  * Returns zero if successful.
 842 */
 843 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 844 {
 845         int rc;
 846         unsigned long flags;
 847         struct srp_login_req *login;
 848         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 849         if (!evt_struct) {
 850                 printk(KERN_ERR
 851                        "ibmvscsi: couldn't allocate an event for login req!\n");
 852                 return FAILED;
 853         }
 854
 855         init_event_struct(evt_struct,
 856                           login_rsp,
 857                           VIOSRP_SRP_FORMAT,
 858                           init_timeout * HZ);
 859
 860         login = &evt_struct->iu.srp.login_req;
 861         memset(login, 0x00, sizeof(struct srp_login_req));
 862         login->opcode = SRP_LOGIN_REQ;
 863         login->req_it_iu_len = sizeof(union srp_iu);
 864         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 865
 866         spin_lock_irqsave(hostdata->host->host_lock, flags);
 867         /* Start out with a request limit of 1, since this is negotiated in
 868          * the login request we are just sending
 869          */
 870         atomic_set(&hostdata->request_limit, 1);
 871
 872         rc = ibmvscsi_send_srp_event(evt_struct, hostdata);
 873         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 874         printk("ibmvscsic: sent SRP login\n");
 875         return rc;
 876 };
 877
 878 /**
 879  * sync_completion: Signal that a synchronous command has completed
 880  * Note that after returning from this call, the evt_struct is freed.
 881  * the caller waiting on this completion shouldn't touch the evt_struct
 882  * again.
 883  */
 884 static void sync_completion(struct srp_event_struct *evt_struct)
 885 {
 886         /* copy the response back */
 887         if (evt_struct->sync_srp)
 888                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
 889
 890         complete(&evt_struct->comp);
 891 }
 892
 893 /**
 894  * ibmvscsi_abort: Abort a command...from scsi host template
 895  * send this over to the server and wait synchronously for the response
 896  */
 897 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
 898 {
 899         struct ibmvscsi_host_data *hostdata =
 900             (struct ibmvscsi_host_data *)cmd->device->host->hostdata;
 901         struct srp_tsk_mgmt *tsk_mgmt;
 902         struct srp_event_struct *evt;
 903         struct srp_event_struct *tmp_evt, *found_evt;
 904         union viosrp_iu srp_rsp;
 905         int rsp_rc;
 906         unsigned long flags;
 907         u16 lun = lun_from_dev(cmd->device);
 908
 909         /* First, find this command in our sent list so we can figure
 910          * out the correct tag
 911          */
 912         spin_lock_irqsave(hostdata->host->host_lock, flags);
 913         found_evt = NULL;
 914         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 915                 if (tmp_evt->cmnd == cmd) {
 916                         found_evt = tmp_evt;
 917                         break;
 918                 }
 919         }
 920
 921         if (!found_evt) {
 922                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 923                 return FAILED;
 924         }
 925
 926         evt = get_event_struct(&hostdata->pool);
 927         if (evt == NULL) {
 928                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 929                 printk(KERN_ERR "ibmvscsi: failed to allocate abort event\n");
 930                 return FAILED;
 931         }
 932
 933         init_event_struct(evt,
 934                           sync_completion,
 935                           VIOSRP_SRP_FORMAT,
 936                           init_timeout * HZ);
 937
 938         tsk_mgmt = &evt->iu.srp.tsk_mgmt;
 939
 940         /* Set up an abort SRP command */
 941         memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
 942         tsk_mgmt->opcode = SRP_TSK_MGMT;
 943         tsk_mgmt->lun = ((u64) lun) << 48;
 944         tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
 945         tsk_mgmt->task_tag = (u64) found_evt;
 946
 947         printk(KERN_INFO "ibmvscsi: aborting command. lun 0x%lx, tag 0x%lx\n",
 948                tsk_mgmt->lun, tsk_mgmt->task_tag);
 949
 950         evt->sync_srp = &srp_rsp;
 951         init_completion(&evt->comp);
 952         rsp_rc = ibmvscsi_send_srp_event(evt, hostdata);
 953         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 954         if (rsp_rc != 0) {
 955                 printk(KERN_ERR "ibmvscsi: failed to send abort() event\n");
 956                 return FAILED;
 957         }
 958
 959         wait_for_completion(&evt->comp);
 960
 961         /* make sure we got a good response */
 962         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
 963                 if (printk_ratelimit())
 964                         printk(KERN_WARNING
 965                                "ibmvscsi: abort bad SRP RSP type %d\n",
 966                                srp_rsp.srp.rsp.opcode);
 967                 return FAILED;
 968         }
 969
 970         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
 971                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
 972         else
 973                 rsp_rc = srp_rsp.srp.rsp.status;
 974
 975         if (rsp_rc) {
 976                 if (printk_ratelimit())
 977                         printk(KERN_WARNING
 978                                "ibmvscsi: abort code %d for task tag 0x%lx\n",
 979                                rsp_rc,
 980                                tsk_mgmt->task_tag);
 981                 return FAILED;
 982         }
 983
 984         /* Because we dropped the spinlock above, it's possible
 985          * The event is no longer in our list.  Make sure it didn't
 986          * complete while we were aborting
 987          */
 988         spin_lock_irqsave(hostdata->host->host_lock, flags);
 989         found_evt = NULL;
 990         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 991                 if (tmp_evt->cmnd == cmd) {
 992                         found_evt = tmp_evt;
 993                         break;
 994                 }
 995         }
 996
 997         if (found_evt == NULL) {
 998                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 999                 printk(KERN_INFO
1000                        "ibmvscsi: aborted task tag 0x%lx completed\n",
1001                        tsk_mgmt->task_tag);
1002                 return SUCCESS;
1003         }
1004
1005         printk(KERN_INFO
1006                "ibmvscsi: successfully aborted task tag 0x%lx\n",
1007                tsk_mgmt->task_tag);
1008
1009         cmd->result = (DID_ABORT << 16);
1010         list_del(&found_evt->list);
1011         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1012                        found_evt->hostdata->dev);
1013         free_event_struct(&found_evt->hostdata->pool, found_evt);
1014         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1015         atomic_inc(&hostdata->request_limit);
1016         return SUCCESS;
1017 }
1018
1019 /**
1020  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1021  * template send this over to the server and wait synchronously for the
1022  * response
1023  */
1024 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1025 {
1026         struct ibmvscsi_host_data *hostdata =
1027             (struct ibmvscsi_host_data *)cmd->device->host->hostdata;
1028
1029         struct srp_tsk_mgmt *tsk_mgmt;
1030         struct srp_event_struct *evt;
1031         struct srp_event_struct *tmp_evt, *pos;
1032         union viosrp_iu srp_rsp;
1033         int rsp_rc;
1034         unsigned long flags;
1035         u16 lun = lun_from_dev(cmd->device);
1036
1037         spin_lock_irqsave(hostdata->host->host_lock, flags);
1038         evt = get_event_struct(&hostdata->pool);
1039         if (evt == NULL) {
1040                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1041                 printk(KERN_ERR "ibmvscsi: failed to allocate reset event\n");
1042                 return FAILED;
1043         }
1044
1045         init_event_struct(evt,
1046                           sync_completion,
1047                           VIOSRP_SRP_FORMAT,
1048                           init_timeout * HZ);
1049
1050         tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1051
1052         /* Set up a lun reset SRP command */
1053         memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1054         tsk_mgmt->opcode = SRP_TSK_MGMT;
1055         tsk_mgmt->lun = ((u64) lun) << 48;
1056         tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1057
1058         printk(KERN_INFO "ibmvscsi: resetting device. lun 0x%lx\n",
1059                tsk_mgmt->lun);
1060
1061         evt->sync_srp = &srp_rsp;
1062         init_completion(&evt->comp);
1063         rsp_rc = ibmvscsi_send_srp_event(evt, hostdata);
1064         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1065         if (rsp_rc != 0) {
1066                 printk(KERN_ERR "ibmvscsi: failed to send reset event\n");
1067                 return FAILED;
1068         }
1069
1070         wait_for_completion(&evt->comp);
1071
1072         /* make sure we got a good response */
1073         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1074                 if (printk_ratelimit())
1075                         printk(KERN_WARNING
1076                                "ibmvscsi: reset bad SRP RSP type %d\n",
1077                                srp_rsp.srp.rsp.opcode);
1078                 return FAILED;
1079         }
1080
1081         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1082                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1083         else
1084                 rsp_rc = srp_rsp.srp.rsp.status;
1085
1086         if (rsp_rc) {
1087                 if (printk_ratelimit())
1088                         printk(KERN_WARNING
1089                                "ibmvscsi: reset code %d for task tag 0x%lx\n",
1090                                rsp_rc, tsk_mgmt->task_tag);
1091                 return FAILED;
1092         }
1093
1094         /* We need to find all commands for this LUN that have not yet been
1095          * responded to, and fail them with DID_RESET
1096          */
1097         spin_lock_irqsave(hostdata->host->host_lock, flags);
1098         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1099                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1100                         if (tmp_evt->cmnd)
1101                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1102                         list_del(&tmp_evt->list);
1103                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1104                                        tmp_evt->hostdata->dev);
1105                         free_event_struct(&tmp_evt->hostdata->pool,
1106                                                    tmp_evt);
1107                         atomic_inc(&hostdata->request_limit);
1108                         if (tmp_evt->cmnd_done)
1109                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1110                         else if (tmp_evt->done)
1111                                 tmp_evt->done(tmp_evt);
1112                 }
1113         }
1114         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1115         return SUCCESS;
1116 }
1117
1118 /**
1119  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
1120  * @hostdata:    the adapter
1121  */
1122 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
1123 {
1124         struct srp_event_struct *tmp_evt, *pos;
1125         unsigned long flags;
1126
1127         spin_lock_irqsave(hostdata->host->host_lock, flags);
1128         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1129                 list_del(&tmp_evt->list);
1130                 if (tmp_evt->cmnd) {
1131                         tmp_evt->cmnd->result = (error_code << 16);
1132                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
1133                                        tmp_evt,
1134                                        tmp_evt->hostdata->dev);
1135                         if (tmp_evt->cmnd_done)
1136                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1137                 } else {
1138                         if (tmp_evt->done) {
1139                                 tmp_evt->done(tmp_evt);
1140                         }
1141                 }
1142                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
1143         }
1144         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1145 }
1146
1147 /**
1148  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1149  * @crq:        Command/Response queue
1150  * @hostdata:   ibmvscsi_host_data of host
1151  *
1152 */
1153 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1154                          struct ibmvscsi_host_data *hostdata)
1155 {
1156         unsigned long flags;
1157         struct srp_event_struct *evt_struct =
1158             (struct srp_event_struct *)crq->IU_data_ptr;
1159         switch (crq->valid) {
1160         case 0xC0:              /* initialization */
1161                 switch (crq->format) {
1162                 case 0x01:      /* Initialization message */
1163                         printk(KERN_INFO "ibmvscsi: partner initialized\n");
1164                         /* Send back a response */
1165                         if (ibmvscsi_send_crq(hostdata,
1166                                               0xC002000000000000LL, 0) == 0) {
1167                                 /* Now login */
1168                                 send_srp_login(hostdata);
1169                         } else {
1170                                 printk(KERN_ERR
1171                                        "ibmvscsi: Unable to send init rsp\n");
1172                         }
1173
1174                         break;
1175                 case 0x02:      /* Initialization response */
1176                         printk(KERN_INFO
1177                                "ibmvscsi: partner initialization complete\n");
1178
1179                         /* Now login */
1180                         send_srp_login(hostdata);
1181                         break;
1182                 default:
1183                         printk(KERN_ERR "ibmvscsi: unknown crq message type\n");
1184                 }
1185                 return;
1186         case 0xFF:      /* Hypervisor telling us the connection is closed */
1187                 scsi_block_requests(hostdata->host);
1188                 if (crq->format == 0x06) {
1189                         /* We need to re-setup the interpartition connection */
1190                         printk(KERN_INFO
1191                                "ibmvscsi: Re-enabling adapter!\n");
1192                         atomic_set(&hostdata->request_limit, -1);
1193                         purge_requests(hostdata, DID_REQUEUE);
1194                         if (ibmvscsi_reenable_crq_queue(&hostdata->queue,
1195                                                         hostdata) == 0)
1196                                 if (ibmvscsi_send_crq(hostdata,
1197                                                       0xC001000000000000LL, 0))
1198                                         printk(KERN_ERR
1199                                                "ibmvscsi: transmit error after"
1200                                                " enable\n");
1201                 } else {
1202                         printk(KERN_INFO
1203                                "ibmvscsi: Virtual adapter failed rc %d!\n",
1204                                crq->format);
1205
1206                         atomic_set(&hostdata->request_limit, -1);
1207                         purge_requests(hostdata, DID_ERROR);
1208                         ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata);
1209                 }
1210                 scsi_unblock_requests(hostdata->host);
1211                 return;
1212         case 0x80:              /* real payload */
1213                 break;
1214         default:
1215                 printk(KERN_ERR
1216                        "ibmvscsi: got an invalid message type 0x%02x\n",
1217                        crq->valid);
1218                 return;
1219         }
1220
1221         /* The only kind of payload CRQs we should get are responses to
1222          * things we send. Make sure this response is to something we
1223          * actually sent
1224          */
1225         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1226                 printk(KERN_ERR
1227                        "ibmvscsi: returned correlation_token 0x%p is invalid!\n",
1228                        (void *)crq->IU_data_ptr);
1229                 return;
1230         }
1231
1232         if (atomic_read(&evt_struct->free)) {
1233                 printk(KERN_ERR
1234                        "ibmvscsi: received duplicate  correlation_token 0x%p!\n",
1235                        (void *)crq->IU_data_ptr);
1236                 return;
1237         }
1238
1239         if (crq->format == VIOSRP_SRP_FORMAT)
1240                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1241                            &hostdata->request_limit);
1242
1243         if (evt_struct->done)
1244                 evt_struct->done(evt_struct);
1245         else
1246                 printk(KERN_ERR
1247                        "ibmvscsi: returned done() is NULL; not running it!\n");
1248
1249         /*
1250          * Lock the host_lock before messing with these structures, since we
1251          * are running in a task context
1252          */
1253         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1254         list_del(&evt_struct->list);
1255         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1256         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1257 }
1258
1259 /**
1260  * ibmvscsi_get_host_config: Send the command to the server to get host
1261  * configuration data.  The data is opaque to us.
1262  */
1263 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1264                                    unsigned char *buffer, int length)
1265 {
1266         struct viosrp_host_config *host_config;
1267         struct srp_event_struct *evt_struct;
1268         dma_addr_t addr;
1269         int rc;
1270
1271         evt_struct = get_event_struct(&hostdata->pool);
1272         if (!evt_struct) {
1273                 printk(KERN_ERR
1274                        "ibmvscsi: could't allocate event for HOST_CONFIG!\n");
1275                 return -1;
1276         }
1277
1278         init_event_struct(evt_struct,
1279                           sync_completion,
1280                           VIOSRP_MAD_FORMAT,
1281                           init_timeout * HZ);
1282
1283         host_config = &evt_struct->iu.mad.host_config;
1284
1285         /* Set up a lun reset SRP command */
1286         memset(host_config, 0x00, sizeof(*host_config));
1287         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1288         host_config->common.length = length;
1289         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1290                                                     length,
1291                                                     DMA_BIDIRECTIONAL);
1292
1293         if (dma_mapping_error(host_config->buffer)) {
1294                 printk(KERN_ERR
1295                        "ibmvscsi: dma_mapping error " "getting host config\n");
1296                 free_event_struct(&hostdata->pool, evt_struct);
1297                 return -1;
1298         }
1299
1300         init_completion(&evt_struct->comp);
1301         rc = ibmvscsi_send_srp_event(evt_struct, hostdata);
1302         if (rc == 0)
1303                 wait_for_completion(&evt_struct->comp);
1304         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1305
1306         return rc;
1307 }
1308
1309 /* ------------------------------------------------------------
1310  * sysfs attributes
1311  */
1312 static ssize_t show_host_srp_version(struct class_device *class_dev, char *buf)
1313 {
1314         struct Scsi_Host *shost = class_to_shost(class_dev);
1315         struct ibmvscsi_host_data *hostdata =
1316             (struct ibmvscsi_host_data *)shost->hostdata;
1317         int len;
1318
1319         len = snprintf(buf, PAGE_SIZE, "%s\n",
1320                        hostdata->madapter_info.srp_version);
1321         return len;
1322 }
1323
1324 static struct class_device_attribute ibmvscsi_host_srp_version = {
1325         .attr = {
1326                  .name = "srp_version",
1327                  .mode = S_IRUGO,
1328                  },
1329         .show = show_host_srp_version,
1330 };
1331
1332 static ssize_t show_host_partition_name(struct class_device *class_dev,
1333                                         char *buf)
1334 {
1335         struct Scsi_Host *shost = class_to_shost(class_dev);
1336         struct ibmvscsi_host_data *hostdata =
1337             (struct ibmvscsi_host_data *)shost->hostdata;
1338         int len;
1339
1340         len = snprintf(buf, PAGE_SIZE, "%s\n",
1341                        hostdata->madapter_info.partition_name);
1342         return len;
1343 }
1344
1345 static struct class_device_attribute ibmvscsi_host_partition_name = {
1346         .attr = {
1347                  .name = "partition_name",
1348                  .mode = S_IRUGO,
1349                  },
1350         .show = show_host_partition_name,
1351 };
1352
1353 static ssize_t show_host_partition_number(struct class_device *class_dev,
1354                                           char *buf)
1355 {
1356         struct Scsi_Host *shost = class_to_shost(class_dev);
1357         struct ibmvscsi_host_data *hostdata =
1358             (struct ibmvscsi_host_data *)shost->hostdata;
1359         int len;
1360
1361         len = snprintf(buf, PAGE_SIZE, "%d\n",
1362                        hostdata->madapter_info.partition_number);
1363         return len;
1364 }
1365
1366 static struct class_device_attribute ibmvscsi_host_partition_number = {
1367         .attr = {
1368                  .name = "partition_number",
1369                  .mode = S_IRUGO,
1370                  },
1371         .show = show_host_partition_number,
1372 };
1373
1374 static ssize_t show_host_mad_version(struct class_device *class_dev, char *buf)
1375 {
1376         struct Scsi_Host *shost = class_to_shost(class_dev);
1377         struct ibmvscsi_host_data *hostdata =
1378             (struct ibmvscsi_host_data *)shost->hostdata;
1379         int len;
1380
1381         len = snprintf(buf, PAGE_SIZE, "%d\n",
1382                        hostdata->madapter_info.mad_version);
1383         return len;
1384 }
1385
1386 static struct class_device_attribute ibmvscsi_host_mad_version = {
1387         .attr = {
1388                  .name = "mad_version",
1389                  .mode = S_IRUGO,
1390                  },
1391         .show = show_host_mad_version,
1392 };
1393
1394 static ssize_t show_host_os_type(struct class_device *class_dev, char *buf)
1395 {
1396         struct Scsi_Host *shost = class_to_shost(class_dev);
1397         struct ibmvscsi_host_data *hostdata =
1398             (struct ibmvscsi_host_data *)shost->hostdata;
1399         int len;
1400
1401         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1402         return len;
1403 }
1404
1405 static struct class_device_attribute ibmvscsi_host_os_type = {
1406         .attr = {
1407                  .name = "os_type",
1408                  .mode = S_IRUGO,
1409                  },
1410         .show = show_host_os_type,
1411 };
1412
1413 static ssize_t show_host_config(struct class_device *class_dev, char *buf)
1414 {
1415         struct Scsi_Host *shost = class_to_shost(class_dev);
1416         struct ibmvscsi_host_data *hostdata =
1417             (struct ibmvscsi_host_data *)shost->hostdata;
1418
1419         /* returns null-terminated host config data */
1420         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1421                 return strlen(buf);
1422         else
1423                 return 0;
1424 }
1425
1426 static struct class_device_attribute ibmvscsi_host_config = {
1427         .attr = {
1428                  .name = "config",
1429                  .mode = S_IRUGO,
1430                  },
1431         .show = show_host_config,
1432 };
1433
1434 static struct class_device_attribute *ibmvscsi_attrs[] = {
1435         &ibmvscsi_host_srp_version,
1436         &ibmvscsi_host_partition_name,
1437         &ibmvscsi_host_partition_number,
1438         &ibmvscsi_host_mad_version,
1439         &ibmvscsi_host_os_type,
1440         &ibmvscsi_host_config,
1441         NULL
1442 };
1443
1444 /* ------------------------------------------------------------
1445  * SCSI driver registration
1446  */
1447 static struct scsi_host_template driver_template = {
1448         .module = THIS_MODULE,
1449         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1450         .proc_name = "ibmvscsi",
1451         .queuecommand = ibmvscsi_queuecommand,
1452         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1453         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1454         .cmd_per_lun = 16,
1455         .can_queue = 1,         /* Updated after SRP_LOGIN */
1456         .this_id = -1,
1457         .sg_tablesize = SG_ALL,
1458         .use_clustering = ENABLE_CLUSTERING,
1459         .shost_attrs = ibmvscsi_attrs,
1460 };
1461
1462 /**
1463  * Called by bus code for each adapter
1464  */
1465 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1466 {
1467         struct ibmvscsi_host_data *hostdata;
1468         struct Scsi_Host *host;
1469         struct device *dev = &vdev->dev;
1470         unsigned long wait_switch = 0;
1471
1472         vdev->dev.driver_data = NULL;
1473
1474         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1475         if (!host) {
1476                 printk(KERN_ERR "ibmvscsi: couldn't allocate host data\n");
1477                 goto scsi_host_alloc_failed;
1478         }
1479
1480         hostdata = (struct ibmvscsi_host_data *)host->hostdata;
1481         memset(hostdata, 0x00, sizeof(*hostdata));
1482         INIT_LIST_HEAD(&hostdata->sent);
1483         hostdata->host = host;
1484         hostdata->dev = dev;
1485         atomic_set(&hostdata->request_limit, -1);
1486         hostdata->host->max_sectors = 32 * 8; /* default max I/O 32 pages */
1487
1488         if (ibmvscsi_init_crq_queue(&hostdata->queue, hostdata,
1489                                     max_requests) != 0) {
1490                 printk(KERN_ERR "ibmvscsi: couldn't initialize crq\n");
1491                 goto init_crq_failed;
1492         }
1493         if (initialize_event_pool(&hostdata->pool, max_requests, hostdata) != 0) {
1494                 printk(KERN_ERR "ibmvscsi: couldn't initialize event pool\n");
1495                 goto init_pool_failed;
1496         }
1497
1498         host->max_lun = 8;
1499         host->max_id = max_id;
1500         host->max_channel = max_channel;
1501
1502         if (scsi_add_host(hostdata->host, hostdata->dev))
1503                 goto add_host_failed;
1504
1505         /* Try to send an initialization message.  Note that this is allowed
1506          * to fail if the other end is not acive.  In that case we don't
1507          * want to scan
1508          */
1509         if (ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0) == 0) {
1510                 /*
1511                  * Wait around max init_timeout secs for the adapter to finish
1512                  * initializing. When we are done initializing, we will have a
1513                  * valid request_limit.  We don't want Linux scanning before
1514                  * we are ready.
1515                  */
1516                 for (wait_switch = jiffies + (init_timeout * HZ);
1517                      time_before(jiffies, wait_switch) &&
1518                      atomic_read(&hostdata->request_limit) < 2;) {
1519
1520                         msleep(10);
1521                 }
1522
1523                 /* if we now have a valid request_limit, initiate a scan */
1524                 if (atomic_read(&hostdata->request_limit) > 0)
1525                         scsi_scan_host(host);
1526         }
1527
1528         vdev->dev.driver_data = hostdata;
1529         return 0;
1530
1531       add_host_failed:
1532         release_event_pool(&hostdata->pool, hostdata);
1533       init_pool_failed:
1534         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata, max_requests);
1535       init_crq_failed:
1536         scsi_host_put(host);
1537       scsi_host_alloc_failed:
1538         return -1;
1539 }
1540
1541 static int ibmvscsi_remove(struct vio_dev *vdev)
1542 {
1543         struct ibmvscsi_host_data *hostdata = vdev->dev.driver_data;
1544         release_event_pool(&hostdata->pool, hostdata);
1545         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
1546                                    max_requests);
1547
1548         scsi_remove_host(hostdata->host);
1549         scsi_host_put(hostdata->host);
1550
1551         return 0;
1552 }
1553
1554 /**
1555  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
1556  * support.
1557  */
1558 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1559         {"vscsi", "IBM,v-scsi"},
1560         { "", "" }
1561 };
1562 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1563
1564 static struct vio_driver ibmvscsi_driver = {
1565         .id_table = ibmvscsi_device_table,
1566         .probe = ibmvscsi_probe,
1567         .remove = ibmvscsi_remove,
1568         .driver = {
1569                 .name = "ibmvscsi",
1570                 .owner = THIS_MODULE,
1571         }
1572 };
1573
1574 int __init ibmvscsi_module_init(void)
1575 {
1576         return vio_register_driver(&ibmvscsi_driver);
1577 }
1578
1579 void __exit ibmvscsi_module_exit(void)
1580 {
1581         vio_unregister_driver(&ibmvscsi_driver);
1582 }
1583
1584 module_init(ibmvscsi_module_init);
1585 module_exit(ibmvscsi_module_exit);