drivers/message/i2o/i2o_scsi.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify it
   3  * under the terms of the GNU General Public License as published by the
   4  * Free Software Foundation; either version 2, or (at your option) any
   5  * later version.
   6  *
   7  * This program is distributed in the hope that it will be useful, but
   8  * WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  10  * General Public License for more details.
  11  *
  12  * For the avoidance of doubt the "preferred form" of this code is one which
  13  * is in an open non patent encumbered format. Where cryptographic key signing
  14  * forms part of the process of creating an executable the information
  15  * including keys needed to generate an equivalently functional executable
  16  * are deemed to be part of the source code.
  17  *
  18  *  Complications for I2O scsi
  19  *
  20  *      o       Each (bus,lun) is a logical device in I2O. We keep a map
  21  *              table. We spoof failed selection for unmapped units
  22  *      o       Request sense buffers can come back for free.
  23  *      o       Scatter gather is a bit dynamic. We have to investigate at
  24  *              setup time.
  25  *      o       Some of our resources are dynamically shared. The i2o core
  26  *              needs a message reservation protocol to avoid swap v net
  27  *              deadlocking. We need to back off queue requests.
  28  *
  29  *      In general the firmware wants to help. Where its help isn't performance
  30  *      useful we just ignore the aid. Its not worth the code in truth.
  31  *
  32  * Fixes/additions:
  33  *      Steve Ralston:
  34  *              Scatter gather now works
  35  *      Markus Lidel <Markus.Lidel@shadowconnect.com>:
  36  *              Minor fixes for 2.6.
  37  *
  38  * To Do:
  39  *      64bit cleanups
  40  *      Fix the resource management problems.
  41  */
  42
  43 #include <linux/module.h>
  44 #include <linux/kernel.h>
  45 #include <linux/types.h>
  46 #include <linux/string.h>
  47 #include <linux/ioport.h>
  48 #include <linux/jiffies.h>
  49 #include <linux/interrupt.h>
  50 #include <linux/timer.h>
  51 #include <linux/delay.h>
  52 #include <linux/proc_fs.h>
  53 #include <linux/prefetch.h>
  54 #include <linux/pci.h>
  55 #include <linux/blkdev.h>
  56 #include <linux/i2o.h>
  57 #include <linux/scatterlist.h>
  58
  59 #include <asm/dma.h>
  60 #include <asm/io.h>
  61 #include <linux/atomic.h>
  62
  63 #include <scsi/scsi.h>
  64 #include <scsi/scsi_host.h>
  65 #include <scsi/scsi_device.h>
  66 #include <scsi/scsi_cmnd.h>
  67 #include <scsi/sg.h>
  68
  69 #define OSM_NAME        "scsi-osm"
  70 #define OSM_VERSION     "1.316"
  71 #define OSM_DESCRIPTION "I2O SCSI Peripheral OSM"
  72
  73 static struct i2o_driver i2o_scsi_driver;
  74
  75 static unsigned int i2o_scsi_max_id = 16;
  76 static unsigned int i2o_scsi_max_lun = 255;
  77
  78 struct i2o_scsi_host {
  79         struct Scsi_Host *scsi_host;    /* pointer to the SCSI host */
  80         struct i2o_controller *iop;     /* pointer to the I2O controller */
  81         u64 lun;        /* lun's used for block devices */
  82         struct i2o_device *channel[0];  /* channel->i2o_dev mapping table */
  83 };
  84
  85 static struct scsi_host_template i2o_scsi_host_template;
  86
  87 #define I2O_SCSI_CAN_QUEUE      4
  88
  89 /* SCSI OSM class handling definition */
  90 static struct i2o_class_id i2o_scsi_class_id[] = {
  91         {I2O_CLASS_SCSI_PERIPHERAL},
  92         {I2O_CLASS_END}
  93 };
  94
  95 static struct i2o_scsi_host *i2o_scsi_host_alloc(struct i2o_controller *c)
  96 {
  97         struct i2o_scsi_host *i2o_shost;
  98         struct i2o_device *i2o_dev;
  99         struct Scsi_Host *scsi_host;
 100         int max_channel = 0;
 101         u8 type;
 102         int i;
 103         size_t size;
 104         u16 body_size = 6;
 105
 106 #ifdef CONFIG_I2O_EXT_ADAPTEC
 107         if (c->adaptec)
 108                 body_size = 8;
 109 #endif
 110
 111         list_for_each_entry(i2o_dev, &c->devices, list)
 112             if (i2o_dev->lct_data.class_id == I2O_CLASS_BUS_ADAPTER) {
 113                 if (!i2o_parm_field_get(i2o_dev, 0x0000, 0, &type, 1)
 114                     && (type == 0x01))  /* SCSI bus */
 115                         max_channel++;
 116         }
 117
 118         if (!max_channel) {
 119                 osm_warn("no channels found on %s\n", c->name);
 120                 return ERR_PTR(-EFAULT);
 121         }
 122
 123         size = max_channel * sizeof(struct i2o_device *)
 124             + sizeof(struct i2o_scsi_host);
 125
 126         scsi_host = scsi_host_alloc(&i2o_scsi_host_template, size);
 127         if (!scsi_host) {
 128                 osm_warn("Could not allocate SCSI host\n");
 129                 return ERR_PTR(-ENOMEM);
 130         }
 131
 132         scsi_host->max_channel = max_channel - 1;
 133         scsi_host->max_id = i2o_scsi_max_id;
 134         scsi_host->max_lun = i2o_scsi_max_lun;
 135         scsi_host->this_id = c->unit;
 136         scsi_host->sg_tablesize = i2o_sg_tablesize(c, body_size);
 137
 138         i2o_shost = (struct i2o_scsi_host *)scsi_host->hostdata;
 139         i2o_shost->scsi_host = scsi_host;
 140         i2o_shost->iop = c;
 141         i2o_shost->lun = 1;
 142
 143         i = 0;
 144         list_for_each_entry(i2o_dev, &c->devices, list)
 145             if (i2o_dev->lct_data.class_id == I2O_CLASS_BUS_ADAPTER) {
 146                 if (!i2o_parm_field_get(i2o_dev, 0x0000, 0, &type, 1)
 147                     && (type == 0x01))  /* only SCSI bus */
 148                         i2o_shost->channel[i++] = i2o_dev;
 149
 150                 if (i >= max_channel)
 151                         break;
 152         }
 153
 154         return i2o_shost;
 155 };
 156
 157 /**
 158  *      i2o_scsi_get_host - Get an I2O SCSI host
 159  *      @c: I2O controller to for which to get the SCSI host
 160  *
 161  *      If the I2O controller already exists as SCSI host, the SCSI host
 162  *      is returned, otherwise the I2O controller is added to the SCSI
 163  *      core.
 164  *
 165  *      Returns pointer to the I2O SCSI host on success or NULL on failure.
 166  */
 167 static struct i2o_scsi_host *i2o_scsi_get_host(struct i2o_controller *c)
 168 {
 169         return c->driver_data[i2o_scsi_driver.context];
 170 };
 171
 172 /**
 173  *      i2o_scsi_remove - Remove I2O device from SCSI core
 174  *      @dev: device which should be removed
 175  *
 176  *      Removes the I2O device from the SCSI core again.
 177  *
 178  *      Returns 0 on success.
 179  */
 180 static int i2o_scsi_remove(struct device *dev)
 181 {
 182         struct i2o_device *i2o_dev = to_i2o_device(dev);
 183         struct i2o_controller *c = i2o_dev->iop;
 184         struct i2o_scsi_host *i2o_shost;
 185         struct scsi_device *scsi_dev;
 186
 187         osm_info("device removed (TID: %03x)\n", i2o_dev->lct_data.tid);
 188
 189         i2o_shost = i2o_scsi_get_host(c);
 190
 191         shost_for_each_device(scsi_dev, i2o_shost->scsi_host)
 192             if (scsi_dev->hostdata == i2o_dev) {
 193                 sysfs_remove_link(&i2o_dev->device.kobj, "scsi");
 194                 scsi_remove_device(scsi_dev);
 195                 scsi_device_put(scsi_dev);
 196                 break;
 197         }
 198
 199         return 0;
 200 };
 201
 202 /**
 203  *      i2o_scsi_probe - verify if dev is a I2O SCSI device and install it
 204  *      @dev: device to verify if it is a I2O SCSI device
 205  *
 206  *      Retrieve channel, id and lun for I2O device. If everything goes well
 207  *      register the I2O device as SCSI device on the I2O SCSI controller.
 208  *
 209  *      Returns 0 on success or negative error code on failure.
 210  */
 211 static int i2o_scsi_probe(struct device *dev)
 212 {
 213         struct i2o_device *i2o_dev = to_i2o_device(dev);
 214         struct i2o_controller *c = i2o_dev->iop;
 215         struct i2o_scsi_host *i2o_shost;
 216         struct Scsi_Host *scsi_host;
 217         struct i2o_device *parent;
 218         struct scsi_device *scsi_dev;
 219         u32 id = -1;
 220         u64 lun = -1;
 221         int channel = -1;
 222         int i, rc;
 223
 224         i2o_shost = i2o_scsi_get_host(c);
 225         if (!i2o_shost)
 226                 return -EFAULT;
 227
 228         scsi_host = i2o_shost->scsi_host;
 229
 230         switch (i2o_dev->lct_data.class_id) {
 231         case I2O_CLASS_RANDOM_BLOCK_STORAGE:
 232         case I2O_CLASS_EXECUTIVE:
 233 #ifdef CONFIG_I2O_EXT_ADAPTEC
 234                 if (c->adaptec) {
 235                         u8 type;
 236                         struct i2o_device *d = i2o_shost->channel[0];
 237
 238                         if (!i2o_parm_field_get(d, 0x0000, 0, &type, 1)
 239                             && (type == 0x01))  /* SCSI bus */
 240                                 if (!i2o_parm_field_get(d, 0x0200, 4, &id, 4)) {
 241                                         channel = 0;
 242                                         if (i2o_dev->lct_data.class_id ==
 243                                             I2O_CLASS_RANDOM_BLOCK_STORAGE)
 244                                                 lun =
 245                                                     cpu_to_le64(i2o_shost->
 246                                                                 lun++);
 247                                         else
 248                                                 lun = 0;
 249                                 }
 250                 }
 251 #endif
 252                 break;
 253
 254         case I2O_CLASS_SCSI_PERIPHERAL:
 255                 if (i2o_parm_field_get(i2o_dev, 0x0000, 3, &id, 4))
 256                         return -EFAULT;
 257
 258                 if (i2o_parm_field_get(i2o_dev, 0x0000, 4, &lun, 8))
 259                         return -EFAULT;
 260
 261                 parent = i2o_iop_find_device(c, i2o_dev->lct_data.parent_tid);
 262                 if (!parent) {
 263                         osm_warn("can not find parent of device %03x\n",
 264                                  i2o_dev->lct_data.tid);
 265                         return -EFAULT;
 266                 }
 267
 268                 for (i = 0; i <= i2o_shost->scsi_host->max_channel; i++)
 269                         if (i2o_shost->channel[i] == parent)
 270                                 channel = i;
 271                 break;
 272
 273         default:
 274                 return -EFAULT;
 275         }
 276
 277         if (channel == -1) {
 278                 osm_warn("can not find channel of device %03x\n",
 279                          i2o_dev->lct_data.tid);
 280                 return -EFAULT;
 281         }
 282
 283         if (le32_to_cpu(id) >= scsi_host->max_id) {
 284                 osm_warn("SCSI device id (%d) >= max_id of I2O host (%d)",
 285                          le32_to_cpu(id), scsi_host->max_id);
 286                 return -EFAULT;
 287         }
 288
 289         if (le64_to_cpu(lun) >= scsi_host->max_lun) {
 290                 osm_warn("SCSI device lun (%llu) >= max_lun of I2O host (%llu)",
 291                          le64_to_cpu(lun), scsi_host->max_lun);
 292                 return -EFAULT;
 293         }
 294
 295         scsi_dev =
 296             __scsi_add_device(i2o_shost->scsi_host, channel, le32_to_cpu(id),
 297                               le64_to_cpu(lun), i2o_dev);
 298
 299         if (IS_ERR(scsi_dev)) {
 300                 osm_warn("can not add SCSI device %03x\n",
 301                          i2o_dev->lct_data.tid);
 302                 return PTR_ERR(scsi_dev);
 303         }
 304
 305         rc = sysfs_create_link(&i2o_dev->device.kobj,
 306                                &scsi_dev->sdev_gendev.kobj, "scsi");
 307         if (rc)
 308                 goto err;
 309
 310         osm_info("device added (TID: %03x) channel: %d, id: %d, lun: %llu\n",
 311                  i2o_dev->lct_data.tid, channel, le32_to_cpu(id),
 312                  le64_to_cpu(lun));
 313
 314         return 0;
 315
 316 err:
 317         scsi_remove_device(scsi_dev);
 318         return rc;
 319 };
 320
 321 static const char *i2o_scsi_info(struct Scsi_Host *SChost)
 322 {
 323         struct i2o_scsi_host *hostdata;
 324         hostdata = (struct i2o_scsi_host *)SChost->hostdata;
 325         return hostdata->iop->name;
 326 }
 327
 328 /**
 329  *      i2o_scsi_reply - SCSI OSM message reply handler
 330  *      @c: controller issuing the reply
 331  *      @m: message id for flushing
 332  *      @msg: the message from the controller
 333  *
 334  *      Process reply messages (interrupts in normal scsi controller think).
 335  *      We can get a variety of messages to process. The normal path is
 336  *      scsi command completions. We must also deal with IOP failures,
 337  *      the reply to a bus reset and the reply to a LUN query.
 338  *
 339  *      Returns 0 on success and if the reply should not be flushed or > 0
 340  *      on success and if the reply should be flushed. Returns negative error
 341  *      code on failure and if the reply should be flushed.
 342  */
 343 static int i2o_scsi_reply(struct i2o_controller *c, u32 m,
 344                           struct i2o_message *msg)
 345 {
 346         struct scsi_cmnd *cmd;
 347         u32 error;
 348         struct device *dev;
 349
 350         cmd = i2o_cntxt_list_get(c, le32_to_cpu(msg->u.s.tcntxt));
 351         if (unlikely(!cmd)) {
 352                 osm_err("NULL reply received!\n");
 353                 return -1;
 354         }
 355
 356         /*
 357          *      Low byte is device status, next is adapter status,
 358          *      (then one byte reserved), then request status.
 359          */
 360         error = le32_to_cpu(msg->body[0]);
 361
 362         osm_debug("Completed %0x%p\n", cmd);
 363
 364         cmd->result = error & 0xff;
 365         /*
 366          * if DeviceStatus is not SCSI_SUCCESS copy over the sense data and let
 367          * the SCSI layer handle the error
 368          */
 369         if (cmd->result)
 370                 memcpy(cmd->sense_buffer, &msg->body[3],
 371                        min(SCSI_SENSE_BUFFERSIZE, 40));
 372
 373         /* only output error code if AdapterStatus is not HBA_SUCCESS */
 374         if ((error >> 8) & 0xff)
 375                 osm_err("SCSI error %08x\n", error);
 376
 377         dev = &c->pdev->dev;
 378
 379         scsi_dma_unmap(cmd);
 380
 381         cmd->scsi_done(cmd);
 382
 383         return 1;
 384 };
 385
 386 /**
 387  *      i2o_scsi_notify_device_add - Retrieve notifications of added devices
 388  *      @i2o_dev: the I2O device which was added
 389  *
 390  *      If a I2O device is added we catch the notification, because I2O classes
 391  *      other than SCSI peripheral will not be received through
 392  *      i2o_scsi_probe().
 393  */
 394 static void i2o_scsi_notify_device_add(struct i2o_device *i2o_dev)
 395 {
 396         switch (i2o_dev->lct_data.class_id) {
 397         case I2O_CLASS_EXECUTIVE:
 398         case I2O_CLASS_RANDOM_BLOCK_STORAGE:
 399                 i2o_scsi_probe(&i2o_dev->device);
 400                 break;
 401
 402         default:
 403                 break;
 404         }
 405 };
 406
 407 /**
 408  *      i2o_scsi_notify_device_remove - Retrieve notifications of removed devices
 409  *      @i2o_dev: the I2O device which was removed
 410  *
 411  *      If a I2O device is removed, we catch the notification to remove the
 412  *      corresponding SCSI device.
 413  */
 414 static void i2o_scsi_notify_device_remove(struct i2o_device *i2o_dev)
 415 {
 416         switch (i2o_dev->lct_data.class_id) {
 417         case I2O_CLASS_EXECUTIVE:
 418         case I2O_CLASS_RANDOM_BLOCK_STORAGE:
 419                 i2o_scsi_remove(&i2o_dev->device);
 420                 break;
 421
 422         default:
 423                 break;
 424         }
 425 };
 426
 427 /**
 428  *      i2o_scsi_notify_controller_add - Retrieve notifications of added controllers
 429  *      @c: the controller which was added
 430  *
 431  *      If a I2O controller is added, we catch the notification to add a
 432  *      corresponding Scsi_Host.
 433  */
 434 static void i2o_scsi_notify_controller_add(struct i2o_controller *c)
 435 {
 436         struct i2o_scsi_host *i2o_shost;
 437         int rc;
 438
 439         i2o_shost = i2o_scsi_host_alloc(c);
 440         if (IS_ERR(i2o_shost)) {
 441                 osm_err("Could not initialize SCSI host\n");
 442                 return;
 443         }
 444
 445         rc = scsi_add_host(i2o_shost->scsi_host, &c->device);
 446         if (rc) {
 447                 osm_err("Could not add SCSI host\n");
 448                 scsi_host_put(i2o_shost->scsi_host);
 449                 return;
 450         }
 451
 452         c->driver_data[i2o_scsi_driver.context] = i2o_shost;
 453
 454         osm_debug("new I2O SCSI host added\n");
 455 };
 456
 457 /**
 458  *      i2o_scsi_notify_controller_remove - Retrieve notifications of removed controllers
 459  *      @c: the controller which was removed
 460  *
 461  *      If a I2O controller is removed, we catch the notification to remove the
 462  *      corresponding Scsi_Host.
 463  */
 464 static void i2o_scsi_notify_controller_remove(struct i2o_controller *c)
 465 {
 466         struct i2o_scsi_host *i2o_shost;
 467         i2o_shost = i2o_scsi_get_host(c);
 468         if (!i2o_shost)
 469                 return;
 470
 471         c->driver_data[i2o_scsi_driver.context] = NULL;
 472
 473         scsi_remove_host(i2o_shost->scsi_host);
 474         scsi_host_put(i2o_shost->scsi_host);
 475         osm_debug("I2O SCSI host removed\n");
 476 };
 477
 478 /* SCSI OSM driver struct */
 479 static struct i2o_driver i2o_scsi_driver = {
 480         .name = OSM_NAME,
 481         .reply = i2o_scsi_reply,
 482         .classes = i2o_scsi_class_id,
 483         .notify_device_add = i2o_scsi_notify_device_add,
 484         .notify_device_remove = i2o_scsi_notify_device_remove,
 485         .notify_controller_add = i2o_scsi_notify_controller_add,
 486         .notify_controller_remove = i2o_scsi_notify_controller_remove,
 487         .driver = {
 488                    .probe = i2o_scsi_probe,
 489                    .remove = i2o_scsi_remove,
 490                    },
 491 };
 492
 493 /**
 494  *      i2o_scsi_queuecommand - queue a SCSI command
 495  *      @SCpnt: scsi command pointer
 496  *      @done: callback for completion
 497  *
 498  *      Issue a scsi command asynchronously. Return 0 on success or 1 if
 499  *      we hit an error (normally message queue congestion). The only
 500  *      minor complication here is that I2O deals with the device addressing
 501  *      so we have to map the bus/dev/lun back to an I2O handle as well
 502  *      as faking absent devices ourself.
 503  *
 504  *      Locks: takes the controller lock on error path only
 505  */
 506
 507 static int i2o_scsi_queuecommand_lck(struct scsi_cmnd *SCpnt,
 508                                  void (*done) (struct scsi_cmnd *))
 509 {
 510         struct i2o_controller *c;
 511         struct i2o_device *i2o_dev;
 512         int tid;
 513         struct i2o_message *msg;
 514         /*
 515          * ENABLE_DISCONNECT
 516          * SIMPLE_TAG
 517          * RETURN_SENSE_DATA_IN_REPLY_MESSAGE_FRAME
 518          */
 519         u32 scsi_flags = 0x20a00000;
 520         u32 sgl_offset;
 521         u32 *mptr;
 522         u32 cmd = I2O_CMD_SCSI_EXEC << 24;
 523         int rc = 0;
 524
 525         /*
 526          *      Do the incoming paperwork
 527          */
 528         i2o_dev = SCpnt->device->hostdata;
 529
 530         SCpnt->scsi_done = done;
 531
 532         if (unlikely(!i2o_dev)) {
 533                 osm_warn("no I2O device in request\n");
 534                 SCpnt->result = DID_NO_CONNECT << 16;
 535                 done(SCpnt);
 536                 goto exit;
 537         }
 538         c = i2o_dev->iop;
 539         tid = i2o_dev->lct_data.tid;
 540
 541         osm_debug("qcmd: Tid = %03x\n", tid);
 542         osm_debug("Real scsi messages.\n");
 543
 544         /*
 545          *      Put together a scsi execscb message
 546          */
 547         switch (SCpnt->sc_data_direction) {
 548         case PCI_DMA_NONE:
 549                 /* DATA NO XFER */
 550                 sgl_offset = SGL_OFFSET_0;
 551                 break;
 552
 553         case PCI_DMA_TODEVICE:
 554                 /* DATA OUT (iop-->dev) */
 555                 scsi_flags |= 0x80000000;
 556                 sgl_offset = SGL_OFFSET_10;
 557                 break;
 558
 559         case PCI_DMA_FROMDEVICE:
 560                 /* DATA IN  (iop<--dev) */
 561                 scsi_flags |= 0x40000000;
 562                 sgl_offset = SGL_OFFSET_10;
 563                 break;
 564
 565         default:
 566                 /* Unknown - kill the command */
 567                 SCpnt->result = DID_NO_CONNECT << 16;
 568                 done(SCpnt);
 569                 goto exit;
 570         }
 571
 572         /*
 573          *      Obtain an I2O message. If there are none free then
 574          *      throw it back to the scsi layer
 575          */
 576
 577         msg = i2o_msg_get(c);
 578         if (IS_ERR(msg)) {
 579                 rc = SCSI_MLQUEUE_HOST_BUSY;
 580                 goto exit;
 581         }
 582
 583         mptr = &msg->body[0];
 584
 585 #if 0 /* this code can't work */
 586 #ifdef CONFIG_I2O_EXT_ADAPTEC
 587         if (c->adaptec) {
 588                 u32 adpt_flags = 0;
 589
 590                 if (SCpnt->sc_request && SCpnt->sc_request->upper_private_data) {
 591                         i2o_sg_io_hdr_t __user *usr_ptr =
 592                             ((Sg_request *) (SCpnt->sc_request->
 593                                              upper_private_data))->header.
 594                             usr_ptr;
 595
 596                         if (usr_ptr)
 597                                 get_user(adpt_flags, &usr_ptr->flags);
 598                 }
 599
 600                 switch (i2o_dev->lct_data.class_id) {
 601                 case I2O_CLASS_EXECUTIVE:
 602                 case I2O_CLASS_RANDOM_BLOCK_STORAGE:
 603                         /* interpret flag has to be set for executive */
 604                         adpt_flags ^= I2O_DPT_SG_FLAG_INTERPRET;
 605                         break;
 606
 607                 default:
 608                         break;
 609                 }
 610
 611                 /*
 612                  * for Adaptec controllers we use the PRIVATE command, because
 613                  * the normal SCSI EXEC doesn't support all SCSI commands on
 614                  * all controllers (for example READ CAPACITY).
 615                  */
 616                 if (sgl_offset == SGL_OFFSET_10)
 617                         sgl_offset = SGL_OFFSET_12;
 618                 cmd = I2O_CMD_PRIVATE << 24;
 619                 *mptr++ = cpu_to_le32(I2O_VENDOR_DPT << 16 | I2O_CMD_SCSI_EXEC);
 620                 *mptr++ = cpu_to_le32(adpt_flags | tid);
 621         }
 622 #endif
 623 #endif
 624
 625         msg->u.head[1] = cpu_to_le32(cmd | HOST_TID << 12 | tid);
 626         msg->u.s.icntxt = cpu_to_le32(i2o_scsi_driver.context);
 627
 628         /* We want the SCSI control block back */
 629         msg->u.s.tcntxt = cpu_to_le32(i2o_cntxt_list_add(c, SCpnt));
 630
 631         /* LSI_920_PCI_QUIRK
 632          *
 633          *      Intermittant observations of msg frame word data corruption
 634          *      observed on msg[4] after:
 635          *        WRITE, READ-MODIFY-WRITE
 636          *      operations.  19990606 -sralston
 637          *
 638          *      (Hence we build this word via tag. Its good practice anyway
 639          *       we don't want fetches over PCI needlessly)
 640          */
 641
 642         /* Attach tags to the devices */
 643         /* FIXME: implement
 644            if(SCpnt->device->tagged_supported) {
 645            if(SCpnt->tag == HEAD_OF_QUEUE_TAG)
 646            scsi_flags |= 0x01000000;
 647            else if(SCpnt->tag == ORDERED_QUEUE_TAG)
 648            scsi_flags |= 0x01800000;
 649            }
 650          */
 651
 652         *mptr++ = cpu_to_le32(scsi_flags | SCpnt->cmd_len);
 653
 654         /* Write SCSI command into the message - always 16 byte block */
 655         memcpy(mptr, SCpnt->cmnd, 16);
 656         mptr += 4;
 657
 658         if (sgl_offset != SGL_OFFSET_0) {
 659                 /* write size of data addressed by SGL */
 660                 *mptr++ = cpu_to_le32(scsi_bufflen(SCpnt));
 661
 662                 /* Now fill in the SGList and command */
 663
 664                 if (scsi_sg_count(SCpnt)) {
 665                         if (!i2o_dma_map_sg(c, scsi_sglist(SCpnt),
 666                                             scsi_sg_count(SCpnt),
 667                                             SCpnt->sc_data_direction, &mptr))
 668                                 goto nomem;
 669                 }
 670         }
 671
 672         /* Stick the headers on */
 673         msg->u.head[0] =
 674             cpu_to_le32(I2O_MESSAGE_SIZE(mptr - &msg->u.head[0]) | sgl_offset);
 675
 676         /* Queue the message */
 677         i2o_msg_post(c, msg);
 678
 679         osm_debug("Issued %0x%p\n", SCpnt);
 680
 681         return 0;
 682
 683       nomem:
 684         rc = -ENOMEM;
 685         i2o_msg_nop(c, msg);
 686
 687       exit:
 688         return rc;
 689 }
 690
 691 static DEF_SCSI_QCMD(i2o_scsi_queuecommand)
 692
 693 /**
 694  *      i2o_scsi_abort - abort a running command
 695  *      @SCpnt: command to abort
 696  *
 697  *      Ask the I2O controller to abort a command. This is an asynchrnous
 698  *      process and our callback handler will see the command complete with an
 699  *      aborted message if it succeeds.
 700  *
 701  *      Returns 0 if the command is successfully aborted or negative error code
 702  *      on failure.
 703  */
 704 static int i2o_scsi_abort(struct scsi_cmnd *SCpnt)
 705 {
 706         struct i2o_device *i2o_dev;
 707         struct i2o_controller *c;
 708         struct i2o_message *msg;
 709         int tid;
 710         int status = FAILED;
 711
 712         osm_warn("Aborting command block.\n");
 713
 714         i2o_dev = SCpnt->device->hostdata;
 715         c = i2o_dev->iop;
 716         tid = i2o_dev->lct_data.tid;
 717
 718         msg = i2o_msg_get_wait(c, I2O_TIMEOUT_MESSAGE_GET);
 719         if (IS_ERR(msg))
 720                 return SCSI_MLQUEUE_HOST_BUSY;
 721
 722         msg->u.head[0] = cpu_to_le32(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0);
 723         msg->u.head[1] =
 724             cpu_to_le32(I2O_CMD_SCSI_ABORT << 24 | HOST_TID << 12 | tid);
 725         msg->body[0] = cpu_to_le32(i2o_cntxt_list_get_ptr(c, SCpnt));
 726
 727         if (!i2o_msg_post_wait(c, msg, I2O_TIMEOUT_SCSI_SCB_ABORT))
 728                 status = SUCCESS;
 729
 730         return status;
 731 }
 732
 733 /**
 734  *      i2o_scsi_bios_param     -       Invent disk geometry
 735  *      @sdev: scsi device
 736  *      @dev: block layer device
 737  *      @capacity: size in sectors
 738  *      @ip: geometry array
 739  *
 740  *      This is anyone's guess quite frankly. We use the same rules everyone
 741  *      else appears to and hope. It seems to work.
 742  */
 743
 744 static int i2o_scsi_bios_param(struct scsi_device *sdev,
 745                                struct block_device *dev, sector_t capacity,
 746                                int *ip)
 747 {
 748         int size;
 749
 750         size = capacity;
 751         ip[0] = 64;             /* heads                        */
 752         ip[1] = 32;             /* sectors                      */
 753         if ((ip[2] = size >> 11) > 1024) {      /* cylinders, test for big disk */
 754                 ip[0] = 255;    /* heads                        */
 755                 ip[1] = 63;     /* sectors                      */
 756                 ip[2] = size / (255 * 63);      /* cylinders                    */
 757         }
 758         return 0;
 759 }
 760
 761 static struct scsi_host_template i2o_scsi_host_template = {
 762         .proc_name = OSM_NAME,
 763         .name = OSM_DESCRIPTION,
 764         .info = i2o_scsi_info,
 765         .queuecommand = i2o_scsi_queuecommand,
 766         .eh_abort_handler = i2o_scsi_abort,
 767         .bios_param = i2o_scsi_bios_param,
 768         .can_queue = I2O_SCSI_CAN_QUEUE,
 769         .sg_tablesize = 8,
 770         .cmd_per_lun = 6,
 771         .use_clustering = ENABLE_CLUSTERING,
 772 };
 773
 774 /**
 775  *      i2o_scsi_init - SCSI OSM initialization function
 776  *
 777  *      Register SCSI OSM into I2O core.
 778  *
 779  *      Returns 0 on success or negative error code on failure.
 780  */
 781 static int __init i2o_scsi_init(void)
 782 {
 783         int rc;
 784
 785         printk(KERN_INFO OSM_DESCRIPTION " v" OSM_VERSION "\n");
 786
 787         /* Register SCSI OSM into I2O core */
 788         rc = i2o_driver_register(&i2o_scsi_driver);
 789         if (rc) {
 790                 osm_err("Could not register SCSI driver\n");
 791                 return rc;
 792         }
 793
 794         return 0;
 795 };
 796
 797 /**
 798  *      i2o_scsi_exit - SCSI OSM exit function
 799  *
 800  *      Unregisters SCSI OSM from I2O core.
 801  */
 802 static void __exit i2o_scsi_exit(void)
 803 {
 804         /* Unregister I2O SCSI OSM from I2O core */
 805         i2o_driver_unregister(&i2o_scsi_driver);
 806 };
 807
 808 MODULE_AUTHOR("Red Hat Software");
 809 MODULE_LICENSE("GPL");
 810 MODULE_DESCRIPTION(OSM_DESCRIPTION);
 811 MODULE_VERSION(OSM_VERSION);
 812
 813 module_init(i2o_scsi_init);
 814 module_exit(i2o_scsi_exit);