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