drivers/firewire/fw-sbp2.c

   1 /*
   2  * SBP2 driver (SCSI over IEEE1394)
   3  *
   4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22  * The basic structure of this driver is based on the old storage driver,
  23  * drivers/ieee1394/sbp2.c, originally written by
  24  *     James Goodwin <jamesg@filanet.com>
  25  * with later contributions and ongoing maintenance from
  26  *     Ben Collins <bcollins@debian.org>,
  27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  28  * and many others.
  29  */
  30
  31 #include <linux/blkdev.h>
  32 #include <linux/delay.h>
  33 #include <linux/device.h>
  34 #include <linux/dma-mapping.h>
  35 #include <linux/kernel.h>
  36 #include <linux/mod_devicetable.h>
  37 #include <linux/module.h>
  38 #include <linux/moduleparam.h>
  39 #include <linux/scatterlist.h>
  40 #include <linux/string.h>
  41 #include <linux/stringify.h>
  42 #include <linux/timer.h>
  43 #include <linux/workqueue.h>
  44 #include <asm/system.h>
  45
  46 #include <scsi/scsi.h>
  47 #include <scsi/scsi_cmnd.h>
  48 #include <scsi/scsi_device.h>
  49 #include <scsi/scsi_host.h>
  50
  51 #include "fw-device.h"
  52 #include "fw-topology.h"
  53 #include "fw-transaction.h"
  54
  55 /*
  56  * So far only bridges from Oxford Semiconductor are known to support
  57  * concurrent logins. Depending on firmware, four or two concurrent logins
  58  * are possible on OXFW911 and newer Oxsemi bridges.
  59  *
  60  * Concurrent logins are useful together with cluster filesystems.
  61  */
  62 static int sbp2_param_exclusive_login = 1;
  63 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  64 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  65                  "(default = Y, use N for concurrent initiators)");
  66
  67 /*
  68  * Flags for firmware oddities
  69  *
  70  * - 128kB max transfer
  71  *   Limit transfer size. Necessary for some old bridges.
  72  *
  73  * - 36 byte inquiry
  74  *   When scsi_mod probes the device, let the inquiry command look like that
  75  *   from MS Windows.
  76  *
  77  * - skip mode page 8
  78  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  79  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  80  *
  81  * - fix capacity
  82  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  83  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  84  *   Don't use this with devices which don't have this bug.
  85  *
  86  * - delay inquiry
  87  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  88  *
  89  * - power condition
  90  *   Set the power condition field in the START STOP UNIT commands sent by
  91  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  92  *   Some disks need this to spin down or to resume properly.
  93  *
  94  * - override internal blacklist
  95  *   Instead of adding to the built-in blacklist, use only the workarounds
  96  *   specified in the module load parameter.
  97  *   Useful if a blacklist entry interfered with a non-broken device.
  98  */
  99 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 100 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 101 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 102 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 103 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 104 #define SBP2_INQUIRY_DELAY              12
 105 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 106 #define SBP2_WORKAROUND_OVERRIDE        0x100
 107
 108 static int sbp2_param_workarounds;
 109 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 110 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 111         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 112         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 113         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 114         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 115         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 116         ", set power condition in start stop unit = "
 117                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 118         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 119         ", or a combination)");
 120
 121 /* I don't know why the SCSI stack doesn't define something like this... */
 122 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
 123
 124 static const char sbp2_driver_name[] = "sbp2";
 125
 126 /*
 127  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 128  * and one struct scsi_device per sbp2_logical_unit.
 129  */
 130 struct sbp2_logical_unit {
 131         struct sbp2_target *tgt;
 132         struct list_head link;
 133         struct fw_address_handler address_handler;
 134         struct list_head orb_list;
 135
 136         u64 command_block_agent_address;
 137         u16 lun;
 138         int login_id;
 139
 140         /*
 141          * The generation is updated once we've logged in or reconnected
 142          * to the logical unit.  Thus, I/O to the device will automatically
 143          * fail and get retried if it happens in a window where the device
 144          * is not ready, e.g. after a bus reset but before we reconnect.
 145          */
 146         int generation;
 147         int retries;
 148         struct delayed_work work;
 149         bool has_sdev;
 150         bool blocked;
 151 };
 152
 153 /*
 154  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 155  * and one struct Scsi_Host per sbp2_target.
 156  */
 157 struct sbp2_target {
 158         struct kref kref;
 159         struct fw_unit *unit;
 160         const char *bus_id;
 161         struct list_head lu_list;
 162
 163         u64 management_agent_address;
 164         u64 guid;
 165         int directory_id;
 166         int node_id;
 167         int address_high;
 168         unsigned int workarounds;
 169         unsigned int mgt_orb_timeout;
 170
 171         int dont_block; /* counter for each logical unit */
 172         int blocked;    /* ditto */
 173 };
 174
 175 /*
 176  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
 177  * provided in the config rom. Most devices do provide a value, which
 178  * we'll use for login management orbs, but with some sane limits.
 179  */
 180 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
 181 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
 182 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
 183 #define SBP2_ORB_NULL                   0x80000000
 184 #define SBP2_MAX_SG_ELEMENT_LENGTH      0xf000
 185 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 186 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 187
 188 /* Unit directory keys */
 189 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 190 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 191 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 192 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 193
 194 /* Management orb opcodes */
 195 #define SBP2_LOGIN_REQUEST              0x0
 196 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 197 #define SBP2_RECONNECT_REQUEST          0x3
 198 #define SBP2_SET_PASSWORD_REQUEST       0x4
 199 #define SBP2_LOGOUT_REQUEST             0x7
 200 #define SBP2_ABORT_TASK_REQUEST         0xb
 201 #define SBP2_ABORT_TASK_SET             0xc
 202 #define SBP2_LOGICAL_UNIT_RESET         0xe
 203 #define SBP2_TARGET_RESET_REQUEST       0xf
 204
 205 /* Offsets for command block agent registers */
 206 #define SBP2_AGENT_STATE                0x00
 207 #define SBP2_AGENT_RESET                0x04
 208 #define SBP2_ORB_POINTER                0x08
 209 #define SBP2_DOORBELL                   0x10
 210 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 211
 212 /* Status write response codes */
 213 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 214 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 215 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 216 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 217
 218 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 219 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 220 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 221 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 222 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 223 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 224 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 225 #define STATUS_GET_DATA(v)              ((v).data)
 226
 227 struct sbp2_status {
 228         u32 status;
 229         u32 orb_low;
 230         u8 data[24];
 231 };
 232
 233 struct sbp2_pointer {
 234         __be32 high;
 235         __be32 low;
 236 };
 237
 238 struct sbp2_orb {
 239         struct fw_transaction t;
 240         struct kref kref;
 241         dma_addr_t request_bus;
 242         int rcode;
 243         struct sbp2_pointer pointer;
 244         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 245         struct list_head link;
 246 };
 247
 248 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 249 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 250 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 251 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 252 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 253 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 254
 255 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 256 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 257
 258 struct sbp2_management_orb {
 259         struct sbp2_orb base;
 260         struct {
 261                 struct sbp2_pointer password;
 262                 struct sbp2_pointer response;
 263                 __be32 misc;
 264                 __be32 length;
 265                 struct sbp2_pointer status_fifo;
 266         } request;
 267         __be32 response[4];
 268         dma_addr_t response_bus;
 269         struct completion done;
 270         struct sbp2_status status;
 271 };
 272
 273 struct sbp2_login_response {
 274         __be32 misc;
 275         struct sbp2_pointer command_block_agent;
 276         __be32 reconnect_hold;
 277 };
 278 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 279 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 280 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 281 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 282 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 283 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 284 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 285 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 286
 287 struct sbp2_command_orb {
 288         struct sbp2_orb base;
 289         struct {
 290                 struct sbp2_pointer next;
 291                 struct sbp2_pointer data_descriptor;
 292                 __be32 misc;
 293                 u8 command_block[12];
 294         } request;
 295         struct scsi_cmnd *cmd;
 296         scsi_done_fn_t done;
 297         struct sbp2_logical_unit *lu;
 298
 299         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 300         dma_addr_t page_table_bus;
 301 };
 302
 303 /*
 304  * List of devices with known bugs.
 305  *
 306  * The firmware_revision field, masked with 0xffff00, is the best
 307  * indicator for the type of bridge chip of a device.  It yields a few
 308  * false positives but this did not break correctly behaving devices
 309  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
 310  * from the config rom can never match that.
 311  */
 312 static const struct {
 313         u32 firmware_revision;
 314         u32 model;
 315         unsigned int workarounds;
 316 } sbp2_workarounds_table[] = {
 317         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 318                 .firmware_revision      = 0x002800,
 319                 .model                  = 0x001010,
 320                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 321                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 322                                           SBP2_WORKAROUND_POWER_CONDITION,
 323         },
 324         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 325                 .firmware_revision      = 0x002800,
 326                 .model                  = 0x000000,
 327                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
 328                                           SBP2_WORKAROUND_POWER_CONDITION,
 329         },
 330         /* Initio bridges, actually only needed for some older ones */ {
 331                 .firmware_revision      = 0x000200,
 332                 .model                  = ~0,
 333                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 334         },
 335         /* PL-3507 bridge with Prolific firmware */ {
 336                 .firmware_revision      = 0x012800,
 337                 .model                  = ~0,
 338                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 339         },
 340         /* Symbios bridge */ {
 341                 .firmware_revision      = 0xa0b800,
 342                 .model                  = ~0,
 343                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 344         },
 345         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 346                 .firmware_revision      = 0x002600,
 347                 .model                  = ~0,
 348                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 349         },
 350
 351         /*
 352          * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
 353          * these iPods do not feature the read_capacity bug according
 354          * to one report.  Read_capacity behaviour as well as model_id
 355          * could change due to Apple-supplied firmware updates though.
 356          */
 357
 358         /* iPod 4th generation. */ {
 359                 .firmware_revision      = 0x0a2700,
 360                 .model                  = 0x000021,
 361                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 362         },
 363         /* iPod mini */ {
 364                 .firmware_revision      = 0x0a2700,
 365                 .model                  = 0x000023,
 366                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 367         },
 368         /* iPod Photo */ {
 369                 .firmware_revision      = 0x0a2700,
 370                 .model                  = 0x00007e,
 371                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 372         }
 373 };
 374
 375 static void
 376 free_orb(struct kref *kref)
 377 {
 378         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 379
 380         kfree(orb);
 381 }
 382
 383 static void
 384 sbp2_status_write(struct fw_card *card, struct fw_request *request,
 385                   int tcode, int destination, int source,
 386                   int generation, int speed,
 387                   unsigned long long offset,
 388                   void *payload, size_t length, void *callback_data)
 389 {
 390         struct sbp2_logical_unit *lu = callback_data;
 391         struct sbp2_orb *orb;
 392         struct sbp2_status status;
 393         size_t header_size;
 394         unsigned long flags;
 395
 396         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 397             length == 0 || length > sizeof(status)) {
 398                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 399                 return;
 400         }
 401
 402         header_size = min(length, 2 * sizeof(u32));
 403         fw_memcpy_from_be32(&status, payload, header_size);
 404         if (length > header_size)
 405                 memcpy(status.data, payload + 8, length - header_size);
 406         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 407                 fw_notify("non-orb related status write, not handled\n");
 408                 fw_send_response(card, request, RCODE_COMPLETE);
 409                 return;
 410         }
 411
 412         /* Lookup the orb corresponding to this status write. */
 413         spin_lock_irqsave(&card->lock, flags);
 414         list_for_each_entry(orb, &lu->orb_list, link) {
 415                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 416                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 417                         orb->rcode = RCODE_COMPLETE;
 418                         list_del(&orb->link);
 419                         break;
 420                 }
 421         }
 422         spin_unlock_irqrestore(&card->lock, flags);
 423
 424         if (&orb->link != &lu->orb_list)
 425                 orb->callback(orb, &status);
 426         else
 427                 fw_error("status write for unknown orb\n");
 428
 429         kref_put(&orb->kref, free_orb);
 430
 431         fw_send_response(card, request, RCODE_COMPLETE);
 432 }
 433
 434 static void
 435 complete_transaction(struct fw_card *card, int rcode,
 436                      void *payload, size_t length, void *data)
 437 {
 438         struct sbp2_orb *orb = data;
 439         unsigned long flags;
 440
 441         /*
 442          * This is a little tricky.  We can get the status write for
 443          * the orb before we get this callback.  The status write
 444          * handler above will assume the orb pointer transaction was
 445          * successful and set the rcode to RCODE_COMPLETE for the orb.
 446          * So this callback only sets the rcode if it hasn't already
 447          * been set and only does the cleanup if the transaction
 448          * failed and we didn't already get a status write.
 449          */
 450         spin_lock_irqsave(&card->lock, flags);
 451
 452         if (orb->rcode == -1)
 453                 orb->rcode = rcode;
 454         if (orb->rcode != RCODE_COMPLETE) {
 455                 list_del(&orb->link);
 456                 spin_unlock_irqrestore(&card->lock, flags);
 457                 orb->callback(orb, NULL);
 458         } else {
 459                 spin_unlock_irqrestore(&card->lock, flags);
 460         }
 461
 462         kref_put(&orb->kref, free_orb);
 463 }
 464
 465 static void
 466 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 467               int node_id, int generation, u64 offset)
 468 {
 469         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 470         unsigned long flags;
 471
 472         orb->pointer.high = 0;
 473         orb->pointer.low = cpu_to_be32(orb->request_bus);
 474
 475         spin_lock_irqsave(&device->card->lock, flags);
 476         list_add_tail(&orb->link, &lu->orb_list);
 477         spin_unlock_irqrestore(&device->card->lock, flags);
 478
 479         /* Take a ref for the orb list and for the transaction callback. */
 480         kref_get(&orb->kref);
 481         kref_get(&orb->kref);
 482
 483         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 484                         node_id, generation, device->max_speed, offset,
 485                         &orb->pointer, sizeof(orb->pointer),
 486                         complete_transaction, orb);
 487 }
 488
 489 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 490 {
 491         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 492         struct sbp2_orb *orb, *next;
 493         struct list_head list;
 494         unsigned long flags;
 495         int retval = -ENOENT;
 496
 497         INIT_LIST_HEAD(&list);
 498         spin_lock_irqsave(&device->card->lock, flags);
 499         list_splice_init(&lu->orb_list, &list);
 500         spin_unlock_irqrestore(&device->card->lock, flags);
 501
 502         list_for_each_entry_safe(orb, next, &list, link) {
 503                 retval = 0;
 504                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 505                         continue;
 506
 507                 orb->rcode = RCODE_CANCELLED;
 508                 orb->callback(orb, NULL);
 509         }
 510
 511         return retval;
 512 }
 513
 514 static void
 515 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 516 {
 517         struct sbp2_management_orb *orb =
 518                 container_of(base_orb, struct sbp2_management_orb, base);
 519
 520         if (status)
 521                 memcpy(&orb->status, status, sizeof(*status));
 522         complete(&orb->done);
 523 }
 524
 525 static int
 526 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 527                          int generation, int function, int lun_or_login_id,
 528                          void *response)
 529 {
 530         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 531         struct sbp2_management_orb *orb;
 532         unsigned int timeout;
 533         int retval = -ENOMEM;
 534
 535         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 536                 return 0;
 537
 538         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 539         if (orb == NULL)
 540                 return -ENOMEM;
 541
 542         kref_init(&orb->base.kref);
 543         orb->response_bus =
 544                 dma_map_single(device->card->device, &orb->response,
 545                                sizeof(orb->response), DMA_FROM_DEVICE);
 546         if (dma_mapping_error(device->card->device, orb->response_bus))
 547                 goto fail_mapping_response;
 548
 549         orb->request.response.high = 0;
 550         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 551
 552         orb->request.misc = cpu_to_be32(
 553                 MANAGEMENT_ORB_NOTIFY |
 554                 MANAGEMENT_ORB_FUNCTION(function) |
 555                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 556         orb->request.length = cpu_to_be32(
 557                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 558
 559         orb->request.status_fifo.high =
 560                 cpu_to_be32(lu->address_handler.offset >> 32);
 561         orb->request.status_fifo.low  =
 562                 cpu_to_be32(lu->address_handler.offset);
 563
 564         if (function == SBP2_LOGIN_REQUEST) {
 565                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 566                 orb->request.misc |= cpu_to_be32(
 567                         MANAGEMENT_ORB_RECONNECT(2) |
 568                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 569                 timeout = lu->tgt->mgt_orb_timeout;
 570         } else {
 571                 timeout = SBP2_ORB_TIMEOUT;
 572         }
 573
 574         init_completion(&orb->done);
 575         orb->base.callback = complete_management_orb;
 576
 577         orb->base.request_bus =
 578                 dma_map_single(device->card->device, &orb->request,
 579                                sizeof(orb->request), DMA_TO_DEVICE);
 580         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 581                 goto fail_mapping_request;
 582
 583         sbp2_send_orb(&orb->base, lu, node_id, generation,
 584                       lu->tgt->management_agent_address);
 585
 586         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 587
 588         retval = -EIO;
 589         if (sbp2_cancel_orbs(lu) == 0) {
 590                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 591                          lu->tgt->bus_id, orb->base.rcode);
 592                 goto out;
 593         }
 594
 595         if (orb->base.rcode != RCODE_COMPLETE) {
 596                 fw_error("%s: management write failed, rcode 0x%02x\n",
 597                          lu->tgt->bus_id, orb->base.rcode);
 598                 goto out;
 599         }
 600
 601         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 602             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 603                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 604                          STATUS_GET_RESPONSE(orb->status),
 605                          STATUS_GET_SBP_STATUS(orb->status));
 606                 goto out;
 607         }
 608
 609         retval = 0;
 610  out:
 611         dma_unmap_single(device->card->device, orb->base.request_bus,
 612                          sizeof(orb->request), DMA_TO_DEVICE);
 613  fail_mapping_request:
 614         dma_unmap_single(device->card->device, orb->response_bus,
 615                          sizeof(orb->response), DMA_FROM_DEVICE);
 616  fail_mapping_response:
 617         if (response)
 618                 memcpy(response, orb->response, sizeof(orb->response));
 619         kref_put(&orb->base.kref, free_orb);
 620
 621         return retval;
 622 }
 623
 624 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 625 {
 626         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 627         __be32 d = 0;
 628
 629         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 630                            lu->tgt->node_id, lu->generation, device->max_speed,
 631                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 632                            &d, sizeof(d));
 633 }
 634
 635 static void
 636 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 637                                    void *payload, size_t length, void *data)
 638 {
 639         kfree(data);
 640 }
 641
 642 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 643 {
 644         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 645         struct fw_transaction *t;
 646         static __be32 d;
 647
 648         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 649         if (t == NULL)
 650                 return;
 651
 652         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 653                         lu->tgt->node_id, lu->generation, device->max_speed,
 654                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 655                         &d, sizeof(d), complete_agent_reset_write_no_wait, t);
 656 }
 657
 658 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
 659 {
 660         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
 661         unsigned long flags;
 662
 663         /* serialize with comparisons of lu->generation and card->generation */
 664         spin_lock_irqsave(&card->lock, flags);
 665         lu->generation = generation;
 666         spin_unlock_irqrestore(&card->lock, flags);
 667 }
 668
 669 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 670 {
 671         /*
 672          * We may access dont_block without taking card->lock here:
 673          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 674          * are currently serialized against each other.
 675          * And a wrong result in sbp2_conditionally_block()'s access of
 676          * dont_block is rather harmless, it simply misses its first chance.
 677          */
 678         --lu->tgt->dont_block;
 679 }
 680
 681 /*
 682  * Blocks lu->tgt if all of the following conditions are met:
 683  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 684  *     logical units have been finished (indicated by dont_block == 0).
 685  *   - lu->generation is stale.
 686  *
 687  * Note, scsi_block_requests() must be called while holding card->lock,
 688  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 689  * unblock the target.
 690  */
 691 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 692 {
 693         struct sbp2_target *tgt = lu->tgt;
 694         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 695         struct Scsi_Host *shost =
 696                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 697         unsigned long flags;
 698
 699         spin_lock_irqsave(&card->lock, flags);
 700         if (!tgt->dont_block && !lu->blocked &&
 701             lu->generation != card->generation) {
 702                 lu->blocked = true;
 703                 if (++tgt->blocked == 1)
 704                         scsi_block_requests(shost);
 705         }
 706         spin_unlock_irqrestore(&card->lock, flags);
 707 }
 708
 709 /*
 710  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 711  * Note, it is harmless to run scsi_unblock_requests() outside the
 712  * card->lock protected section.  On the other hand, running it inside
 713  * the section might clash with shost->host_lock.
 714  */
 715 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 716 {
 717         struct sbp2_target *tgt = lu->tgt;
 718         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 719         struct Scsi_Host *shost =
 720                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 721         unsigned long flags;
 722         bool unblock = false;
 723
 724         spin_lock_irqsave(&card->lock, flags);
 725         if (lu->blocked && lu->generation == card->generation) {
 726                 lu->blocked = false;
 727                 unblock = --tgt->blocked == 0;
 728         }
 729         spin_unlock_irqrestore(&card->lock, flags);
 730
 731         if (unblock)
 732                 scsi_unblock_requests(shost);
 733 }
 734
 735 /*
 736  * Prevents future blocking of tgt and unblocks it.
 737  * Note, it is harmless to run scsi_unblock_requests() outside the
 738  * card->lock protected section.  On the other hand, running it inside
 739  * the section might clash with shost->host_lock.
 740  */
 741 static void sbp2_unblock(struct sbp2_target *tgt)
 742 {
 743         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 744         struct Scsi_Host *shost =
 745                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 746         unsigned long flags;
 747
 748         spin_lock_irqsave(&card->lock, flags);
 749         ++tgt->dont_block;
 750         spin_unlock_irqrestore(&card->lock, flags);
 751
 752         scsi_unblock_requests(shost);
 753 }
 754
 755 static int sbp2_lun2int(u16 lun)
 756 {
 757         struct scsi_lun eight_bytes_lun;
 758
 759         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 760         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 761         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 762
 763         return scsilun_to_int(&eight_bytes_lun);
 764 }
 765
 766 static void sbp2_release_target(struct kref *kref)
 767 {
 768         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 769         struct sbp2_logical_unit *lu, *next;
 770         struct Scsi_Host *shost =
 771                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 772         struct scsi_device *sdev;
 773         struct fw_device *device = fw_device(tgt->unit->device.parent);
 774
 775         /* prevent deadlocks */
 776         sbp2_unblock(tgt);
 777
 778         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 779                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 780                 if (sdev) {
 781                         scsi_remove_device(sdev);
 782                         scsi_device_put(sdev);
 783                 }
 784                 sbp2_send_management_orb(lu, tgt->node_id, lu->generation,
 785                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 786
 787                 fw_core_remove_address_handler(&lu->address_handler);
 788                 list_del(&lu->link);
 789                 kfree(lu);
 790         }
 791         scsi_remove_host(shost);
 792         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
 793
 794         fw_unit_put(tgt->unit);
 795         scsi_host_put(shost);
 796         fw_device_put(device);
 797 }
 798
 799 static struct workqueue_struct *sbp2_wq;
 800
 801 /*
 802  * Always get the target's kref when scheduling work on one its units.
 803  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 804  */
 805 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 806 {
 807         if (queue_delayed_work(sbp2_wq, &lu->work, delay))
 808                 kref_get(&lu->tgt->kref);
 809 }
 810
 811 static void sbp2_target_put(struct sbp2_target *tgt)
 812 {
 813         kref_put(&tgt->kref, sbp2_release_target);
 814 }
 815
 816 /*
 817  * Write retransmit retry values into the BUSY_TIMEOUT register.
 818  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 819  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 820  *   saner value after logging into the device.
 821  * - The dual-phase retry protocol is optional to implement, and if not
 822  *   supported, writes to the dual-phase portion of the register will be
 823  *   ignored. We try to write the original 1394-1995 default here.
 824  * - In the case of devices that are also SBP-3-compliant, all writes are
 825  *   ignored, as the register is read-only, but contains single-phase retry of
 826  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 827  *   write attempt is safe and yields more consistent behavior for all devices.
 828  *
 829  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 830  * and section 6.4 of the SBP-3 spec for further details.
 831  */
 832 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 833 {
 834         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 835         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 836
 837         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 838                            lu->tgt->node_id, lu->generation, device->max_speed,
 839                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
 840                            &d, sizeof(d));
 841 }
 842
 843 static void sbp2_reconnect(struct work_struct *work);
 844
 845 static void sbp2_login(struct work_struct *work)
 846 {
 847         struct sbp2_logical_unit *lu =
 848                 container_of(work, struct sbp2_logical_unit, work.work);
 849         struct sbp2_target *tgt = lu->tgt;
 850         struct fw_device *device = fw_device(tgt->unit->device.parent);
 851         struct Scsi_Host *shost;
 852         struct scsi_device *sdev;
 853         struct sbp2_login_response response;
 854         int generation, node_id, local_node_id;
 855
 856         if (fw_device_is_shutdown(device))
 857                 goto out;
 858
 859         generation    = device->generation;
 860         smp_rmb();    /* node_id must not be older than generation */
 861         node_id       = device->node_id;
 862         local_node_id = device->card->node_id;
 863
 864         /* If this is a re-login attempt, log out, or we might be rejected. */
 865         if (lu->has_sdev)
 866                 sbp2_send_management_orb(lu, device->node_id, generation,
 867                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 868
 869         if (sbp2_send_management_orb(lu, node_id, generation,
 870                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 871                 if (lu->retries++ < 5) {
 872                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 873                 } else {
 874                         fw_error("%s: failed to login to LUN %04x\n",
 875                                  tgt->bus_id, lu->lun);
 876                         /* Let any waiting I/O fail from now on. */
 877                         sbp2_unblock(lu->tgt);
 878                 }
 879                 goto out;
 880         }
 881
 882         tgt->node_id      = node_id;
 883         tgt->address_high = local_node_id << 16;
 884         sbp2_set_generation(lu, generation);
 885
 886         lu->command_block_agent_address =
 887                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 888                       << 32) | be32_to_cpu(response.command_block_agent.low);
 889         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 890
 891         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 892                   tgt->bus_id, lu->lun, lu->retries);
 893
 894         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 895         sbp2_set_busy_timeout(lu);
 896
 897         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 898         sbp2_agent_reset(lu);
 899
 900         /* This was a re-login. */
 901         if (lu->has_sdev) {
 902                 sbp2_cancel_orbs(lu);
 903                 sbp2_conditionally_unblock(lu);
 904                 goto out;
 905         }
 906
 907         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 908                 ssleep(SBP2_INQUIRY_DELAY);
 909
 910         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 911         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 912         /*
 913          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 914          * Therefore __scsi_add_device() will get into trouble if a bus reset
 915          * happens in parallel.  It will either fail or leave us with an
 916          * unusable sdev.  As a workaround we check for this and retry the
 917          * whole login and SCSI probing.
 918          */
 919
 920         /* Reported error during __scsi_add_device() */
 921         if (IS_ERR(sdev))
 922                 goto out_logout_login;
 923
 924         /* Unreported error during __scsi_add_device() */
 925         smp_rmb(); /* get current card generation */
 926         if (generation != device->card->generation) {
 927                 scsi_remove_device(sdev);
 928                 scsi_device_put(sdev);
 929                 goto out_logout_login;
 930         }
 931
 932         /* No error during __scsi_add_device() */
 933         lu->has_sdev = true;
 934         scsi_device_put(sdev);
 935         sbp2_allow_block(lu);
 936         goto out;
 937
 938  out_logout_login:
 939         smp_rmb(); /* generation may have changed */
 940         generation = device->generation;
 941         smp_rmb(); /* node_id must not be older than generation */
 942
 943         sbp2_send_management_orb(lu, device->node_id, generation,
 944                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 945         /*
 946          * If a bus reset happened, sbp2_update will have requeued
 947          * lu->work already.  Reset the work from reconnect to login.
 948          */
 949         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 950  out:
 951         sbp2_target_put(tgt);
 952 }
 953
 954 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 955 {
 956         struct sbp2_logical_unit *lu;
 957
 958         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 959         if (!lu)
 960                 return -ENOMEM;
 961
 962         lu->address_handler.length           = 0x100;
 963         lu->address_handler.address_callback = sbp2_status_write;
 964         lu->address_handler.callback_data    = lu;
 965
 966         if (fw_core_add_address_handler(&lu->address_handler,
 967                                         &fw_high_memory_region) < 0) {
 968                 kfree(lu);
 969                 return -ENOMEM;
 970         }
 971
 972         lu->tgt      = tgt;
 973         lu->lun      = lun_entry & 0xffff;
 974         lu->retries  = 0;
 975         lu->has_sdev = false;
 976         lu->blocked  = false;
 977         ++tgt->dont_block;
 978         INIT_LIST_HEAD(&lu->orb_list);
 979         INIT_DELAYED_WORK(&lu->work, sbp2_login);
 980
 981         list_add_tail(&lu->link, &tgt->lu_list);
 982         return 0;
 983 }
 984
 985 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
 986 {
 987         struct fw_csr_iterator ci;
 988         int key, value;
 989
 990         fw_csr_iterator_init(&ci, directory);
 991         while (fw_csr_iterator_next(&ci, &key, &value))
 992                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
 993                     sbp2_add_logical_unit(tgt, value) < 0)
 994                         return -ENOMEM;
 995         return 0;
 996 }
 997
 998 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
 999                               u32 *model, u32 *firmware_revision)
1000 {
1001         struct fw_csr_iterator ci;
1002         int key, value;
1003         unsigned int timeout;
1004
1005         fw_csr_iterator_init(&ci, directory);
1006         while (fw_csr_iterator_next(&ci, &key, &value)) {
1007                 switch (key) {
1008
1009                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1010                         tgt->management_agent_address =
1011                                         CSR_REGISTER_BASE + 4 * value;
1012                         break;
1013
1014                 case CSR_DIRECTORY_ID:
1015                         tgt->directory_id = value;
1016                         break;
1017
1018                 case CSR_MODEL:
1019                         *model = value;
1020                         break;
1021
1022                 case SBP2_CSR_FIRMWARE_REVISION:
1023                         *firmware_revision = value;
1024                         break;
1025
1026                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1027                         /* the timeout value is stored in 500ms units */
1028                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1029                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1030                         tgt->mgt_orb_timeout =
1031                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1032
1033                         if (timeout > tgt->mgt_orb_timeout)
1034                                 fw_notify("%s: config rom contains %ds "
1035                                           "management ORB timeout, limiting "
1036                                           "to %ds\n", tgt->bus_id,
1037                                           timeout / 1000,
1038                                           tgt->mgt_orb_timeout / 1000);
1039                         break;
1040
1041                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1042                         if (sbp2_add_logical_unit(tgt, value) < 0)
1043                                 return -ENOMEM;
1044                         break;
1045
1046                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1047                         /* Adjust for the increment in the iterator */
1048                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1049                                 return -ENOMEM;
1050                         break;
1051                 }
1052         }
1053         return 0;
1054 }
1055
1056 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1057                                   u32 firmware_revision)
1058 {
1059         int i;
1060         unsigned int w = sbp2_param_workarounds;
1061
1062         if (w)
1063                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1064                           "if you need the workarounds parameter for %s\n",
1065                           tgt->bus_id);
1066
1067         if (w & SBP2_WORKAROUND_OVERRIDE)
1068                 goto out;
1069
1070         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1071
1072                 if (sbp2_workarounds_table[i].firmware_revision !=
1073                     (firmware_revision & 0xffffff00))
1074                         continue;
1075
1076                 if (sbp2_workarounds_table[i].model != model &&
1077                     sbp2_workarounds_table[i].model != ~0)
1078                         continue;
1079
1080                 w |= sbp2_workarounds_table[i].workarounds;
1081                 break;
1082         }
1083  out:
1084         if (w)
1085                 fw_notify("Workarounds for %s: 0x%x "
1086                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1087                           tgt->bus_id, w, firmware_revision, model);
1088         tgt->workarounds = w;
1089 }
1090
1091 static struct scsi_host_template scsi_driver_template;
1092
1093 static int sbp2_probe(struct device *dev)
1094 {
1095         struct fw_unit *unit = fw_unit(dev);
1096         struct fw_device *device = fw_device(unit->device.parent);
1097         struct sbp2_target *tgt;
1098         struct sbp2_logical_unit *lu;
1099         struct Scsi_Host *shost;
1100         u32 model, firmware_revision;
1101
1102         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1103         if (shost == NULL)
1104                 return -ENOMEM;
1105
1106         tgt = (struct sbp2_target *)shost->hostdata;
1107         unit->device.driver_data = tgt;
1108         tgt->unit = unit;
1109         kref_init(&tgt->kref);
1110         INIT_LIST_HEAD(&tgt->lu_list);
1111         tgt->bus_id = unit->device.bus_id;
1112         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1113
1114         if (fw_device_enable_phys_dma(device) < 0)
1115                 goto fail_shost_put;
1116
1117         if (scsi_add_host(shost, &unit->device) < 0)
1118                 goto fail_shost_put;
1119
1120         fw_device_get(device);
1121         fw_unit_get(unit);
1122
1123         /* Initialize to values that won't match anything in our table. */
1124         firmware_revision = 0xff000000;
1125         model = 0xff000000;
1126
1127         /* implicit directory ID */
1128         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1129                              + CSR_CONFIG_ROM) & 0xffffff;
1130
1131         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1132                                &firmware_revision) < 0)
1133                 goto fail_tgt_put;
1134
1135         sbp2_init_workarounds(tgt, model, firmware_revision);
1136
1137         /* Do the login in a workqueue so we can easily reschedule retries. */
1138         list_for_each_entry(lu, &tgt->lu_list, link)
1139                 sbp2_queue_work(lu, 0);
1140         return 0;
1141
1142  fail_tgt_put:
1143         sbp2_target_put(tgt);
1144         return -ENOMEM;
1145
1146  fail_shost_put:
1147         scsi_host_put(shost);
1148         return -ENOMEM;
1149 }
1150
1151 static int sbp2_remove(struct device *dev)
1152 {
1153         struct fw_unit *unit = fw_unit(dev);
1154         struct sbp2_target *tgt = unit->device.driver_data;
1155
1156         sbp2_target_put(tgt);
1157         return 0;
1158 }
1159
1160 static void sbp2_reconnect(struct work_struct *work)
1161 {
1162         struct sbp2_logical_unit *lu =
1163                 container_of(work, struct sbp2_logical_unit, work.work);
1164         struct sbp2_target *tgt = lu->tgt;
1165         struct fw_device *device = fw_device(tgt->unit->device.parent);
1166         int generation, node_id, local_node_id;
1167
1168         if (fw_device_is_shutdown(device))
1169                 goto out;
1170
1171         generation    = device->generation;
1172         smp_rmb();    /* node_id must not be older than generation */
1173         node_id       = device->node_id;
1174         local_node_id = device->card->node_id;
1175
1176         if (sbp2_send_management_orb(lu, node_id, generation,
1177                                      SBP2_RECONNECT_REQUEST,
1178                                      lu->login_id, NULL) < 0) {
1179                 /*
1180                  * If reconnect was impossible even though we are in the
1181                  * current generation, fall back and try to log in again.
1182                  *
1183                  * We could check for "Function rejected" status, but
1184                  * looking at the bus generation as simpler and more general.
1185                  */
1186                 smp_rmb(); /* get current card generation */
1187                 if (generation == device->card->generation ||
1188                     lu->retries++ >= 5) {
1189                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1190                         lu->retries = 0;
1191                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1192                 }
1193                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1194                 goto out;
1195         }
1196
1197         tgt->node_id      = node_id;
1198         tgt->address_high = local_node_id << 16;
1199         sbp2_set_generation(lu, generation);
1200
1201         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1202                   tgt->bus_id, lu->lun, lu->retries);
1203
1204         sbp2_agent_reset(lu);
1205         sbp2_cancel_orbs(lu);
1206         sbp2_conditionally_unblock(lu);
1207  out:
1208         sbp2_target_put(tgt);
1209 }
1210
1211 static void sbp2_update(struct fw_unit *unit)
1212 {
1213         struct sbp2_target *tgt = unit->device.driver_data;
1214         struct sbp2_logical_unit *lu;
1215
1216         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1217
1218         /*
1219          * Fw-core serializes sbp2_update() against sbp2_remove().
1220          * Iteration over tgt->lu_list is therefore safe here.
1221          */
1222         list_for_each_entry(lu, &tgt->lu_list, link) {
1223                 sbp2_conditionally_block(lu);
1224                 lu->retries = 0;
1225                 sbp2_queue_work(lu, 0);
1226         }
1227 }
1228
1229 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1230 #define SBP2_SW_VERSION_ENTRY   0x00010483
1231
1232 static const struct fw_device_id sbp2_id_table[] = {
1233         {
1234                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1235                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1236                 .version      = SBP2_SW_VERSION_ENTRY,
1237         },
1238         { }
1239 };
1240
1241 static struct fw_driver sbp2_driver = {
1242         .driver   = {
1243                 .owner  = THIS_MODULE,
1244                 .name   = sbp2_driver_name,
1245                 .bus    = &fw_bus_type,
1246                 .probe  = sbp2_probe,
1247                 .remove = sbp2_remove,
1248         },
1249         .update   = sbp2_update,
1250         .id_table = sbp2_id_table,
1251 };
1252
1253 static unsigned int
1254 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1255 {
1256         int sam_status;
1257
1258         sense_data[0] = 0x70;
1259         sense_data[1] = 0x0;
1260         sense_data[2] = sbp2_status[1];
1261         sense_data[3] = sbp2_status[4];
1262         sense_data[4] = sbp2_status[5];
1263         sense_data[5] = sbp2_status[6];
1264         sense_data[6] = sbp2_status[7];
1265         sense_data[7] = 10;
1266         sense_data[8] = sbp2_status[8];
1267         sense_data[9] = sbp2_status[9];
1268         sense_data[10] = sbp2_status[10];
1269         sense_data[11] = sbp2_status[11];
1270         sense_data[12] = sbp2_status[2];
1271         sense_data[13] = sbp2_status[3];
1272         sense_data[14] = sbp2_status[12];
1273         sense_data[15] = sbp2_status[13];
1274
1275         sam_status = sbp2_status[0] & 0x3f;
1276
1277         switch (sam_status) {
1278         case SAM_STAT_GOOD:
1279         case SAM_STAT_CHECK_CONDITION:
1280         case SAM_STAT_CONDITION_MET:
1281         case SAM_STAT_BUSY:
1282         case SAM_STAT_RESERVATION_CONFLICT:
1283         case SAM_STAT_COMMAND_TERMINATED:
1284                 return DID_OK << 16 | sam_status;
1285
1286         default:
1287                 return DID_ERROR << 16;
1288         }
1289 }
1290
1291 static void
1292 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1293 {
1294         struct sbp2_command_orb *orb =
1295                 container_of(base_orb, struct sbp2_command_orb, base);
1296         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1297         int result;
1298
1299         if (status != NULL) {
1300                 if (STATUS_GET_DEAD(*status))
1301                         sbp2_agent_reset_no_wait(orb->lu);
1302
1303                 switch (STATUS_GET_RESPONSE(*status)) {
1304                 case SBP2_STATUS_REQUEST_COMPLETE:
1305                         result = DID_OK << 16;
1306                         break;
1307                 case SBP2_STATUS_TRANSPORT_FAILURE:
1308                         result = DID_BUS_BUSY << 16;
1309                         break;
1310                 case SBP2_STATUS_ILLEGAL_REQUEST:
1311                 case SBP2_STATUS_VENDOR_DEPENDENT:
1312                 default:
1313                         result = DID_ERROR << 16;
1314                         break;
1315                 }
1316
1317                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1318                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1319                                                            orb->cmd->sense_buffer);
1320         } else {
1321                 /*
1322                  * If the orb completes with status == NULL, something
1323                  * went wrong, typically a bus reset happened mid-orb
1324                  * or when sending the write (less likely).
1325                  */
1326                 result = DID_BUS_BUSY << 16;
1327                 sbp2_conditionally_block(orb->lu);
1328         }
1329
1330         dma_unmap_single(device->card->device, orb->base.request_bus,
1331                          sizeof(orb->request), DMA_TO_DEVICE);
1332
1333         if (scsi_sg_count(orb->cmd) > 0)
1334                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1335                              scsi_sg_count(orb->cmd),
1336                              orb->cmd->sc_data_direction);
1337
1338         if (orb->page_table_bus != 0)
1339                 dma_unmap_single(device->card->device, orb->page_table_bus,
1340                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1341
1342         orb->cmd->result = result;
1343         orb->done(orb->cmd);
1344 }
1345
1346 static int
1347 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1348                      struct sbp2_logical_unit *lu)
1349 {
1350         struct scatterlist *sg;
1351         int sg_len, l, i, j, count;
1352         dma_addr_t sg_addr;
1353
1354         sg = scsi_sglist(orb->cmd);
1355         count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1356                            orb->cmd->sc_data_direction);
1357         if (count == 0)
1358                 goto fail;
1359
1360         /*
1361          * Handle the special case where there is only one element in
1362          * the scatter list by converting it to an immediate block
1363          * request. This is also a workaround for broken devices such
1364          * as the second generation iPod which doesn't support page
1365          * tables.
1366          */
1367         if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) {
1368                 orb->request.data_descriptor.high =
1369                         cpu_to_be32(lu->tgt->address_high);
1370                 orb->request.data_descriptor.low  =
1371                         cpu_to_be32(sg_dma_address(sg));
1372                 orb->request.misc |=
1373                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1374                 return 0;
1375         }
1376
1377         /*
1378          * Convert the scatterlist to an sbp2 page table.  If any
1379          * scatterlist entries are too big for sbp2, we split them as we
1380          * go.  Even if we ask the block I/O layer to not give us sg
1381          * elements larger than 65535 bytes, some IOMMUs may merge sg elements
1382          * during DMA mapping, and Linux currently doesn't prevent this.
1383          */
1384         for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) {
1385                 sg_len = sg_dma_len(sg);
1386                 sg_addr = sg_dma_address(sg);
1387                 while (sg_len) {
1388                         /* FIXME: This won't get us out of the pinch. */
1389                         if (unlikely(j >= ARRAY_SIZE(orb->page_table))) {
1390                                 fw_error("page table overflow\n");
1391                                 goto fail_page_table;
1392                         }
1393                         l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH);
1394                         orb->page_table[j].low = cpu_to_be32(sg_addr);
1395                         orb->page_table[j].high = cpu_to_be32(l << 16);
1396                         sg_addr += l;
1397                         sg_len -= l;
1398                         j++;
1399                 }
1400         }
1401
1402         orb->page_table_bus =
1403                 dma_map_single(device->card->device, orb->page_table,
1404                                sizeof(orb->page_table), DMA_TO_DEVICE);
1405         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1406                 goto fail_page_table;
1407
1408         /*
1409          * The data_descriptor pointer is the one case where we need
1410          * to fill in the node ID part of the address.  All other
1411          * pointers assume that the data referenced reside on the
1412          * initiator (i.e. us), but data_descriptor can refer to data
1413          * on other nodes so we need to put our ID in descriptor.high.
1414          */
1415         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1416         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1417         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1418                                          COMMAND_ORB_DATA_SIZE(j));
1419
1420         return 0;
1421
1422  fail_page_table:
1423         dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1424                      orb->cmd->sc_data_direction);
1425  fail:
1426         return -ENOMEM;
1427 }
1428
1429 /* SCSI stack integration */
1430
1431 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1432 {
1433         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1434         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1435         struct sbp2_command_orb *orb;
1436         unsigned int max_payload;
1437         int retval = SCSI_MLQUEUE_HOST_BUSY;
1438
1439         /*
1440          * Bidirectional commands are not yet implemented, and unknown
1441          * transfer direction not handled.
1442          */
1443         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1444                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1445                 cmd->result = DID_ERROR << 16;
1446                 done(cmd);
1447                 return 0;
1448         }
1449
1450         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1451         if (orb == NULL) {
1452                 fw_notify("failed to alloc orb\n");
1453                 return SCSI_MLQUEUE_HOST_BUSY;
1454         }
1455
1456         /* Initialize rcode to something not RCODE_COMPLETE. */
1457         orb->base.rcode = -1;
1458         kref_init(&orb->base.kref);
1459
1460         orb->lu   = lu;
1461         orb->done = done;
1462         orb->cmd  = cmd;
1463
1464         orb->request.next.high   = cpu_to_be32(SBP2_ORB_NULL);
1465         /*
1466          * At speed 100 we can do 512 bytes per packet, at speed 200,
1467          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1468          * specifies the max payload size as 2 ^ (max_payload + 2), so
1469          * if we set this to max_speed + 7, we get the right value.
1470          */
1471         max_payload = min(device->max_speed + 7,
1472                           device->card->max_receive - 1);
1473         orb->request.misc = cpu_to_be32(
1474                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1475                 COMMAND_ORB_SPEED(device->max_speed) |
1476                 COMMAND_ORB_NOTIFY);
1477
1478         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1479                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1480
1481         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1482                 goto out;
1483
1484         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1485
1486         orb->base.callback = complete_command_orb;
1487         orb->base.request_bus =
1488                 dma_map_single(device->card->device, &orb->request,
1489                                sizeof(orb->request), DMA_TO_DEVICE);
1490         if (dma_mapping_error(device->card->device, orb->base.request_bus))
1491                 goto out;
1492
1493         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, lu->generation,
1494                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1495         retval = 0;
1496  out:
1497         kref_put(&orb->base.kref, free_orb);
1498         return retval;
1499 }
1500
1501 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1502 {
1503         struct sbp2_logical_unit *lu = sdev->hostdata;
1504
1505         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1506         if (!lu)
1507                 return -ENOSYS;
1508
1509         sdev->allow_restart = 1;
1510
1511         /* SBP-2 requires quadlet alignment of the data buffers. */
1512         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1513
1514         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1515                 sdev->inquiry_len = 36;
1516
1517         return 0;
1518 }
1519
1520 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1521 {
1522         struct sbp2_logical_unit *lu = sdev->hostdata;
1523
1524         sdev->use_10_for_rw = 1;
1525
1526         if (sbp2_param_exclusive_login)
1527                 sdev->manage_start_stop = 1;
1528
1529         if (sdev->type == TYPE_ROM)
1530                 sdev->use_10_for_ms = 1;
1531
1532         if (sdev->type == TYPE_DISK &&
1533             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1534                 sdev->skip_ms_page_8 = 1;
1535
1536         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1537                 sdev->fix_capacity = 1;
1538
1539         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1540                 sdev->start_stop_pwr_cond = 1;
1541
1542         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1543                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1544
1545         return 0;
1546 }
1547
1548 /*
1549  * Called by scsi stack when something has really gone wrong.  Usually
1550  * called when a command has timed-out for some reason.
1551  */
1552 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1553 {
1554         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1555
1556         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1557         sbp2_agent_reset(lu);
1558         sbp2_cancel_orbs(lu);
1559
1560         return SUCCESS;
1561 }
1562
1563 /*
1564  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1565  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1566  *
1567  * This is the concatenation of target port identifier and logical unit
1568  * identifier as per SAM-2...SAM-4 annex A.
1569  */
1570 static ssize_t
1571 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1572                             char *buf)
1573 {
1574         struct scsi_device *sdev = to_scsi_device(dev);
1575         struct sbp2_logical_unit *lu;
1576
1577         if (!sdev)
1578                 return 0;
1579
1580         lu = sdev->hostdata;
1581
1582         return sprintf(buf, "%016llx:%06x:%04x\n",
1583                         (unsigned long long)lu->tgt->guid,
1584                         lu->tgt->directory_id, lu->lun);
1585 }
1586
1587 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1588
1589 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1590         &dev_attr_ieee1394_id,
1591         NULL
1592 };
1593
1594 static struct scsi_host_template scsi_driver_template = {
1595         .module                 = THIS_MODULE,
1596         .name                   = "SBP-2 IEEE-1394",
1597         .proc_name              = sbp2_driver_name,
1598         .queuecommand           = sbp2_scsi_queuecommand,
1599         .slave_alloc            = sbp2_scsi_slave_alloc,
1600         .slave_configure        = sbp2_scsi_slave_configure,
1601         .eh_abort_handler       = sbp2_scsi_abort,
1602         .this_id                = -1,
1603         .sg_tablesize           = SG_ALL,
1604         .use_clustering         = ENABLE_CLUSTERING,
1605         .cmd_per_lun            = 1,
1606         .can_queue              = 1,
1607         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1608 };
1609
1610 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1611 MODULE_DESCRIPTION("SCSI over IEEE1394");
1612 MODULE_LICENSE("GPL");
1613 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1614
1615 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1616 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1617 MODULE_ALIAS("sbp2");
1618 #endif
1619
1620 static int __init sbp2_init(void)
1621 {
1622         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1623         if (!sbp2_wq)
1624                 return -ENOMEM;
1625
1626         return driver_register(&sbp2_driver.driver);
1627 }
1628
1629 static void __exit sbp2_cleanup(void)
1630 {
1631         driver_unregister(&sbp2_driver.driver);
1632         destroy_workqueue(sbp2_wq);
1633 }
1634
1635 module_init(sbp2_init);
1636 module_exit(sbp2_cleanup);