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/bug.h>
  33 #include <linux/delay.h>
  34 #include <linux/device.h>
  35 #include <linux/dma-mapping.h>
  36 #include <linux/kernel.h>
  37 #include <linux/mod_devicetable.h>
  38 #include <linux/module.h>
  39 #include <linux/moduleparam.h>
  40 #include <linux/scatterlist.h>
  41 #include <linux/string.h>
  42 #include <linux/stringify.h>
  43 #include <linux/timer.h>
  44 #include <linux/workqueue.h>
  45 #include <asm/system.h>
  46
  47 #include <scsi/scsi.h>
  48 #include <scsi/scsi_cmnd.h>
  49 #include <scsi/scsi_device.h>
  50 #include <scsi/scsi_host.h>
  51
  52 #include "fw-device.h"
  53 #include "fw-topology.h"
  54 #include "fw-transaction.h"
  55
  56 /*
  57  * So far only bridges from Oxford Semiconductor are known to support
  58  * concurrent logins. Depending on firmware, four or two concurrent logins
  59  * are possible on OXFW911 and newer Oxsemi bridges.
  60  *
  61  * Concurrent logins are useful together with cluster filesystems.
  62  */
  63 static int sbp2_param_exclusive_login = 1;
  64 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  65 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  66                  "(default = Y, use N for concurrent initiators)");
  67
  68 /*
  69  * Flags for firmware oddities
  70  *
  71  * - 128kB max transfer
  72  *   Limit transfer size. Necessary for some old bridges.
  73  *
  74  * - 36 byte inquiry
  75  *   When scsi_mod probes the device, let the inquiry command look like that
  76  *   from MS Windows.
  77  *
  78  * - skip mode page 8
  79  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  80  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  81  *
  82  * - fix capacity
  83  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  84  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  85  *   Don't use this with devices which don't have this bug.
  86  *
  87  * - delay inquiry
  88  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  89  *
  90  * - power condition
  91  *   Set the power condition field in the START STOP UNIT commands sent by
  92  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  93  *   Some disks need this to spin down or to resume properly.
  94  *
  95  * - override internal blacklist
  96  *   Instead of adding to the built-in blacklist, use only the workarounds
  97  *   specified in the module load parameter.
  98  *   Useful if a blacklist entry interfered with a non-broken device.
  99  */
 100 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 101 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 102 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 103 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 104 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 105 #define SBP2_INQUIRY_DELAY              12
 106 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 107 #define SBP2_WORKAROUND_OVERRIDE        0x100
 108
 109 static int sbp2_param_workarounds;
 110 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 111 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 112         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 113         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 114         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 115         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 116         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 117         ", set power condition in start stop unit = "
 118                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 119         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 120         ", or a combination)");
 121
 122 /* I don't know why the SCSI stack doesn't define something like this... */
 123 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
 124
 125 static const char sbp2_driver_name[] = "sbp2";
 126
 127 /*
 128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 129  * and one struct scsi_device per sbp2_logical_unit.
 130  */
 131 struct sbp2_logical_unit {
 132         struct sbp2_target *tgt;
 133         struct list_head link;
 134         struct fw_address_handler address_handler;
 135         struct list_head orb_list;
 136
 137         u64 command_block_agent_address;
 138         u16 lun;
 139         int login_id;
 140
 141         /*
 142          * The generation is updated once we've logged in or reconnected
 143          * to the logical unit.  Thus, I/O to the device will automatically
 144          * fail and get retried if it happens in a window where the device
 145          * is not ready, e.g. after a bus reset but before we reconnect.
 146          */
 147         int generation;
 148         int retries;
 149         struct delayed_work work;
 150         bool has_sdev;
 151         bool blocked;
 152 };
 153
 154 /*
 155  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 156  * and one struct Scsi_Host per sbp2_target.
 157  */
 158 struct sbp2_target {
 159         struct kref kref;
 160         struct fw_unit *unit;
 161         const char *bus_id;
 162         struct list_head lu_list;
 163
 164         u64 management_agent_address;
 165         u64 guid;
 166         int directory_id;
 167         int node_id;
 168         int address_high;
 169         unsigned int workarounds;
 170         unsigned int mgt_orb_timeout;
 171
 172         int dont_block; /* counter for each logical unit */
 173         int blocked;    /* ditto */
 174 };
 175
 176 /* Impossible login_id, to detect logout attempt before successful login */
 177 #define INVALID_LOGIN_ID 0x10000
 178
 179 /*
 180  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
 181  * provided in the config rom. Most devices do provide a value, which
 182  * we'll use for login management orbs, but with some sane limits.
 183  */
 184 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
 185 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
 186 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
 187 #define SBP2_ORB_NULL                   0x80000000
 188 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 189 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 190
 191 /*
 192  * The default maximum s/g segment size of a FireWire controller is
 193  * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
 194  * be quadlet-aligned, we set the length limit to 0xffff & ~3.
 195  */
 196 #define SBP2_MAX_SEG_SIZE               0xfffc
 197
 198 /* Unit directory keys */
 199 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 200 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 201 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 202 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 203
 204 /* Management orb opcodes */
 205 #define SBP2_LOGIN_REQUEST              0x0
 206 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 207 #define SBP2_RECONNECT_REQUEST          0x3
 208 #define SBP2_SET_PASSWORD_REQUEST       0x4
 209 #define SBP2_LOGOUT_REQUEST             0x7
 210 #define SBP2_ABORT_TASK_REQUEST         0xb
 211 #define SBP2_ABORT_TASK_SET             0xc
 212 #define SBP2_LOGICAL_UNIT_RESET         0xe
 213 #define SBP2_TARGET_RESET_REQUEST       0xf
 214
 215 /* Offsets for command block agent registers */
 216 #define SBP2_AGENT_STATE                0x00
 217 #define SBP2_AGENT_RESET                0x04
 218 #define SBP2_ORB_POINTER                0x08
 219 #define SBP2_DOORBELL                   0x10
 220 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 221
 222 /* Status write response codes */
 223 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 224 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 225 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 226 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 227
 228 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 229 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 230 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 231 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 232 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 233 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 234 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 235 #define STATUS_GET_DATA(v)              ((v).data)
 236
 237 struct sbp2_status {
 238         u32 status;
 239         u32 orb_low;
 240         u8 data[24];
 241 };
 242
 243 struct sbp2_pointer {
 244         __be32 high;
 245         __be32 low;
 246 };
 247
 248 struct sbp2_orb {
 249         struct fw_transaction t;
 250         struct kref kref;
 251         dma_addr_t request_bus;
 252         int rcode;
 253         struct sbp2_pointer pointer;
 254         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 255         struct list_head link;
 256 };
 257
 258 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 259 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 260 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 261 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 262 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 263 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 264
 265 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 266 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 267
 268 struct sbp2_management_orb {
 269         struct sbp2_orb base;
 270         struct {
 271                 struct sbp2_pointer password;
 272                 struct sbp2_pointer response;
 273                 __be32 misc;
 274                 __be32 length;
 275                 struct sbp2_pointer status_fifo;
 276         } request;
 277         __be32 response[4];
 278         dma_addr_t response_bus;
 279         struct completion done;
 280         struct sbp2_status status;
 281 };
 282
 283 struct sbp2_login_response {
 284         __be32 misc;
 285         struct sbp2_pointer command_block_agent;
 286         __be32 reconnect_hold;
 287 };
 288 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 289 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 290 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 291 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 292 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 293 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 294 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 295 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 296
 297 struct sbp2_command_orb {
 298         struct sbp2_orb base;
 299         struct {
 300                 struct sbp2_pointer next;
 301                 struct sbp2_pointer data_descriptor;
 302                 __be32 misc;
 303                 u8 command_block[12];
 304         } request;
 305         struct scsi_cmnd *cmd;
 306         scsi_done_fn_t done;
 307         struct sbp2_logical_unit *lu;
 308
 309         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 310         dma_addr_t page_table_bus;
 311 };
 312
 313 /*
 314  * List of devices with known bugs.
 315  *
 316  * The firmware_revision field, masked with 0xffff00, is the best
 317  * indicator for the type of bridge chip of a device.  It yields a few
 318  * false positives but this did not break correctly behaving devices
 319  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
 320  * from the config rom can never match that.
 321  */
 322 static const struct {
 323         u32 firmware_revision;
 324         u32 model;
 325         unsigned int workarounds;
 326 } sbp2_workarounds_table[] = {
 327         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 328                 .firmware_revision      = 0x002800,
 329                 .model                  = 0x001010,
 330                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 331                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 332                                           SBP2_WORKAROUND_POWER_CONDITION,
 333         },
 334         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 335                 .firmware_revision      = 0x002800,
 336                 .model                  = 0x000000,
 337                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
 338                                           SBP2_WORKAROUND_POWER_CONDITION,
 339         },
 340         /* Initio bridges, actually only needed for some older ones */ {
 341                 .firmware_revision      = 0x000200,
 342                 .model                  = ~0,
 343                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 344         },
 345         /* PL-3507 bridge with Prolific firmware */ {
 346                 .firmware_revision      = 0x012800,
 347                 .model                  = ~0,
 348                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 349         },
 350         /* Symbios bridge */ {
 351                 .firmware_revision      = 0xa0b800,
 352                 .model                  = ~0,
 353                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 354         },
 355         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 356                 .firmware_revision      = 0x002600,
 357                 .model                  = ~0,
 358                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 359         },
 360
 361         /*
 362          * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
 363          * these iPods do not feature the read_capacity bug according
 364          * to one report.  Read_capacity behaviour as well as model_id
 365          * could change due to Apple-supplied firmware updates though.
 366          */
 367
 368         /* iPod 4th generation. */ {
 369                 .firmware_revision      = 0x0a2700,
 370                 .model                  = 0x000021,
 371                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 372         },
 373         /* iPod mini */ {
 374                 .firmware_revision      = 0x0a2700,
 375                 .model                  = 0x000022,
 376                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 377         },
 378         /* iPod mini */ {
 379                 .firmware_revision      = 0x0a2700,
 380                 .model                  = 0x000023,
 381                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 382         },
 383         /* iPod Photo */ {
 384                 .firmware_revision      = 0x0a2700,
 385                 .model                  = 0x00007e,
 386                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 387         }
 388 };
 389
 390 static void
 391 free_orb(struct kref *kref)
 392 {
 393         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 394
 395         kfree(orb);
 396 }
 397
 398 static void
 399 sbp2_status_write(struct fw_card *card, struct fw_request *request,
 400                   int tcode, int destination, int source,
 401                   int generation, int speed,
 402                   unsigned long long offset,
 403                   void *payload, size_t length, void *callback_data)
 404 {
 405         struct sbp2_logical_unit *lu = callback_data;
 406         struct sbp2_orb *orb;
 407         struct sbp2_status status;
 408         size_t header_size;
 409         unsigned long flags;
 410
 411         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 412             length == 0 || length > sizeof(status)) {
 413                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 414                 return;
 415         }
 416
 417         header_size = min(length, 2 * sizeof(u32));
 418         fw_memcpy_from_be32(&status, payload, header_size);
 419         if (length > header_size)
 420                 memcpy(status.data, payload + 8, length - header_size);
 421         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 422                 fw_notify("non-orb related status write, not handled\n");
 423                 fw_send_response(card, request, RCODE_COMPLETE);
 424                 return;
 425         }
 426
 427         /* Lookup the orb corresponding to this status write. */
 428         spin_lock_irqsave(&card->lock, flags);
 429         list_for_each_entry(orb, &lu->orb_list, link) {
 430                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 431                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 432                         orb->rcode = RCODE_COMPLETE;
 433                         list_del(&orb->link);
 434                         break;
 435                 }
 436         }
 437         spin_unlock_irqrestore(&card->lock, flags);
 438
 439         if (&orb->link != &lu->orb_list)
 440                 orb->callback(orb, &status);
 441         else
 442                 fw_error("status write for unknown orb\n");
 443
 444         kref_put(&orb->kref, free_orb);
 445
 446         fw_send_response(card, request, RCODE_COMPLETE);
 447 }
 448
 449 static void
 450 complete_transaction(struct fw_card *card, int rcode,
 451                      void *payload, size_t length, void *data)
 452 {
 453         struct sbp2_orb *orb = data;
 454         unsigned long flags;
 455
 456         /*
 457          * This is a little tricky.  We can get the status write for
 458          * the orb before we get this callback.  The status write
 459          * handler above will assume the orb pointer transaction was
 460          * successful and set the rcode to RCODE_COMPLETE for the orb.
 461          * So this callback only sets the rcode if it hasn't already
 462          * been set and only does the cleanup if the transaction
 463          * failed and we didn't already get a status write.
 464          */
 465         spin_lock_irqsave(&card->lock, flags);
 466
 467         if (orb->rcode == -1)
 468                 orb->rcode = rcode;
 469         if (orb->rcode != RCODE_COMPLETE) {
 470                 list_del(&orb->link);
 471                 spin_unlock_irqrestore(&card->lock, flags);
 472                 orb->callback(orb, NULL);
 473         } else {
 474                 spin_unlock_irqrestore(&card->lock, flags);
 475         }
 476
 477         kref_put(&orb->kref, free_orb);
 478 }
 479
 480 static void
 481 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 482               int node_id, int generation, u64 offset)
 483 {
 484         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 485         unsigned long flags;
 486
 487         orb->pointer.high = 0;
 488         orb->pointer.low = cpu_to_be32(orb->request_bus);
 489
 490         spin_lock_irqsave(&device->card->lock, flags);
 491         list_add_tail(&orb->link, &lu->orb_list);
 492         spin_unlock_irqrestore(&device->card->lock, flags);
 493
 494         /* Take a ref for the orb list and for the transaction callback. */
 495         kref_get(&orb->kref);
 496         kref_get(&orb->kref);
 497
 498         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 499                         node_id, generation, device->max_speed, offset,
 500                         &orb->pointer, sizeof(orb->pointer),
 501                         complete_transaction, orb);
 502 }
 503
 504 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 505 {
 506         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 507         struct sbp2_orb *orb, *next;
 508         struct list_head list;
 509         unsigned long flags;
 510         int retval = -ENOENT;
 511
 512         INIT_LIST_HEAD(&list);
 513         spin_lock_irqsave(&device->card->lock, flags);
 514         list_splice_init(&lu->orb_list, &list);
 515         spin_unlock_irqrestore(&device->card->lock, flags);
 516
 517         list_for_each_entry_safe(orb, next, &list, link) {
 518                 retval = 0;
 519                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 520                         continue;
 521
 522                 orb->rcode = RCODE_CANCELLED;
 523                 orb->callback(orb, NULL);
 524         }
 525
 526         return retval;
 527 }
 528
 529 static void
 530 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 531 {
 532         struct sbp2_management_orb *orb =
 533                 container_of(base_orb, struct sbp2_management_orb, base);
 534
 535         if (status)
 536                 memcpy(&orb->status, status, sizeof(*status));
 537         complete(&orb->done);
 538 }
 539
 540 static int
 541 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 542                          int generation, int function, int lun_or_login_id,
 543                          void *response)
 544 {
 545         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 546         struct sbp2_management_orb *orb;
 547         unsigned int timeout;
 548         int retval = -ENOMEM;
 549
 550         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 551                 return 0;
 552
 553         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 554         if (orb == NULL)
 555                 return -ENOMEM;
 556
 557         kref_init(&orb->base.kref);
 558         orb->response_bus =
 559                 dma_map_single(device->card->device, &orb->response,
 560                                sizeof(orb->response), DMA_FROM_DEVICE);
 561         if (dma_mapping_error(device->card->device, orb->response_bus))
 562                 goto fail_mapping_response;
 563
 564         orb->request.response.high = 0;
 565         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 566
 567         orb->request.misc = cpu_to_be32(
 568                 MANAGEMENT_ORB_NOTIFY |
 569                 MANAGEMENT_ORB_FUNCTION(function) |
 570                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 571         orb->request.length = cpu_to_be32(
 572                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 573
 574         orb->request.status_fifo.high =
 575                 cpu_to_be32(lu->address_handler.offset >> 32);
 576         orb->request.status_fifo.low  =
 577                 cpu_to_be32(lu->address_handler.offset);
 578
 579         if (function == SBP2_LOGIN_REQUEST) {
 580                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 581                 orb->request.misc |= cpu_to_be32(
 582                         MANAGEMENT_ORB_RECONNECT(2) |
 583                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 584                 timeout = lu->tgt->mgt_orb_timeout;
 585         } else {
 586                 timeout = SBP2_ORB_TIMEOUT;
 587         }
 588
 589         init_completion(&orb->done);
 590         orb->base.callback = complete_management_orb;
 591
 592         orb->base.request_bus =
 593                 dma_map_single(device->card->device, &orb->request,
 594                                sizeof(orb->request), DMA_TO_DEVICE);
 595         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 596                 goto fail_mapping_request;
 597
 598         sbp2_send_orb(&orb->base, lu, node_id, generation,
 599                       lu->tgt->management_agent_address);
 600
 601         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 602
 603         retval = -EIO;
 604         if (sbp2_cancel_orbs(lu) == 0) {
 605                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 606                          lu->tgt->bus_id, orb->base.rcode);
 607                 goto out;
 608         }
 609
 610         if (orb->base.rcode != RCODE_COMPLETE) {
 611                 fw_error("%s: management write failed, rcode 0x%02x\n",
 612                          lu->tgt->bus_id, orb->base.rcode);
 613                 goto out;
 614         }
 615
 616         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 617             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 618                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 619                          STATUS_GET_RESPONSE(orb->status),
 620                          STATUS_GET_SBP_STATUS(orb->status));
 621                 goto out;
 622         }
 623
 624         retval = 0;
 625  out:
 626         dma_unmap_single(device->card->device, orb->base.request_bus,
 627                          sizeof(orb->request), DMA_TO_DEVICE);
 628  fail_mapping_request:
 629         dma_unmap_single(device->card->device, orb->response_bus,
 630                          sizeof(orb->response), DMA_FROM_DEVICE);
 631  fail_mapping_response:
 632         if (response)
 633                 memcpy(response, orb->response, sizeof(orb->response));
 634         kref_put(&orb->base.kref, free_orb);
 635
 636         return retval;
 637 }
 638
 639 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 640 {
 641         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 642         __be32 d = 0;
 643
 644         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 645                            lu->tgt->node_id, lu->generation, device->max_speed,
 646                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 647                            &d, sizeof(d));
 648 }
 649
 650 static void
 651 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 652                                    void *payload, size_t length, void *data)
 653 {
 654         kfree(data);
 655 }
 656
 657 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 658 {
 659         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 660         struct fw_transaction *t;
 661         static __be32 d;
 662
 663         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 664         if (t == NULL)
 665                 return;
 666
 667         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 668                         lu->tgt->node_id, lu->generation, device->max_speed,
 669                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 670                         &d, sizeof(d), complete_agent_reset_write_no_wait, t);
 671 }
 672
 673 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
 674 {
 675         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
 676         unsigned long flags;
 677
 678         /* serialize with comparisons of lu->generation and card->generation */
 679         spin_lock_irqsave(&card->lock, flags);
 680         lu->generation = generation;
 681         spin_unlock_irqrestore(&card->lock, flags);
 682 }
 683
 684 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 685 {
 686         /*
 687          * We may access dont_block without taking card->lock here:
 688          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 689          * are currently serialized against each other.
 690          * And a wrong result in sbp2_conditionally_block()'s access of
 691          * dont_block is rather harmless, it simply misses its first chance.
 692          */
 693         --lu->tgt->dont_block;
 694 }
 695
 696 /*
 697  * Blocks lu->tgt if all of the following conditions are met:
 698  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 699  *     logical units have been finished (indicated by dont_block == 0).
 700  *   - lu->generation is stale.
 701  *
 702  * Note, scsi_block_requests() must be called while holding card->lock,
 703  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 704  * unblock the target.
 705  */
 706 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 707 {
 708         struct sbp2_target *tgt = lu->tgt;
 709         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 710         struct Scsi_Host *shost =
 711                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 712         unsigned long flags;
 713
 714         spin_lock_irqsave(&card->lock, flags);
 715         if (!tgt->dont_block && !lu->blocked &&
 716             lu->generation != card->generation) {
 717                 lu->blocked = true;
 718                 if (++tgt->blocked == 1)
 719                         scsi_block_requests(shost);
 720         }
 721         spin_unlock_irqrestore(&card->lock, flags);
 722 }
 723
 724 /*
 725  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 726  * Note, it is harmless to run scsi_unblock_requests() outside the
 727  * card->lock protected section.  On the other hand, running it inside
 728  * the section might clash with shost->host_lock.
 729  */
 730 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 731 {
 732         struct sbp2_target *tgt = lu->tgt;
 733         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 734         struct Scsi_Host *shost =
 735                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 736         unsigned long flags;
 737         bool unblock = false;
 738
 739         spin_lock_irqsave(&card->lock, flags);
 740         if (lu->blocked && lu->generation == card->generation) {
 741                 lu->blocked = false;
 742                 unblock = --tgt->blocked == 0;
 743         }
 744         spin_unlock_irqrestore(&card->lock, flags);
 745
 746         if (unblock)
 747                 scsi_unblock_requests(shost);
 748 }
 749
 750 /*
 751  * Prevents future blocking of tgt and unblocks it.
 752  * Note, it is harmless to run scsi_unblock_requests() outside the
 753  * card->lock protected section.  On the other hand, running it inside
 754  * the section might clash with shost->host_lock.
 755  */
 756 static void sbp2_unblock(struct sbp2_target *tgt)
 757 {
 758         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 759         struct Scsi_Host *shost =
 760                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 761         unsigned long flags;
 762
 763         spin_lock_irqsave(&card->lock, flags);
 764         ++tgt->dont_block;
 765         spin_unlock_irqrestore(&card->lock, flags);
 766
 767         scsi_unblock_requests(shost);
 768 }
 769
 770 static int sbp2_lun2int(u16 lun)
 771 {
 772         struct scsi_lun eight_bytes_lun;
 773
 774         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 775         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 776         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 777
 778         return scsilun_to_int(&eight_bytes_lun);
 779 }
 780
 781 static void sbp2_release_target(struct kref *kref)
 782 {
 783         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 784         struct sbp2_logical_unit *lu, *next;
 785         struct Scsi_Host *shost =
 786                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 787         struct scsi_device *sdev;
 788         struct fw_device *device = fw_device(tgt->unit->device.parent);
 789
 790         /* prevent deadlocks */
 791         sbp2_unblock(tgt);
 792
 793         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 794                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 795                 if (sdev) {
 796                         scsi_remove_device(sdev);
 797                         scsi_device_put(sdev);
 798                 }
 799                 if (lu->login_id != INVALID_LOGIN_ID) {
 800                         int generation, node_id;
 801                         /*
 802                          * tgt->node_id may be obsolete here if we failed
 803                          * during initial login or after a bus reset where
 804                          * the topology changed.
 805                          */
 806                         generation = device->generation;
 807                         smp_rmb(); /* node_id vs. generation */
 808                         node_id    = device->node_id;
 809                         sbp2_send_management_orb(lu, node_id, generation,
 810                                                  SBP2_LOGOUT_REQUEST,
 811                                                  lu->login_id, NULL);
 812                 }
 813                 fw_core_remove_address_handler(&lu->address_handler);
 814                 list_del(&lu->link);
 815                 kfree(lu);
 816         }
 817         scsi_remove_host(shost);
 818         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
 819
 820         fw_unit_put(tgt->unit);
 821         scsi_host_put(shost);
 822         fw_device_put(device);
 823 }
 824
 825 static struct workqueue_struct *sbp2_wq;
 826
 827 static void sbp2_target_put(struct sbp2_target *tgt)
 828 {
 829         kref_put(&tgt->kref, sbp2_release_target);
 830 }
 831
 832 /*
 833  * Always get the target's kref when scheduling work on one its units.
 834  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 835  */
 836 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 837 {
 838         kref_get(&lu->tgt->kref);
 839         if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
 840                 sbp2_target_put(lu->tgt);
 841 }
 842
 843 /*
 844  * Write retransmit retry values into the BUSY_TIMEOUT register.
 845  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 846  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 847  *   saner value after logging into the device.
 848  * - The dual-phase retry protocol is optional to implement, and if not
 849  *   supported, writes to the dual-phase portion of the register will be
 850  *   ignored. We try to write the original 1394-1995 default here.
 851  * - In the case of devices that are also SBP-3-compliant, all writes are
 852  *   ignored, as the register is read-only, but contains single-phase retry of
 853  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 854  *   write attempt is safe and yields more consistent behavior for all devices.
 855  *
 856  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 857  * and section 6.4 of the SBP-3 spec for further details.
 858  */
 859 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 860 {
 861         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 862         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 863
 864         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 865                            lu->tgt->node_id, lu->generation, device->max_speed,
 866                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
 867                            &d, sizeof(d));
 868 }
 869
 870 static void sbp2_reconnect(struct work_struct *work);
 871
 872 static void sbp2_login(struct work_struct *work)
 873 {
 874         struct sbp2_logical_unit *lu =
 875                 container_of(work, struct sbp2_logical_unit, work.work);
 876         struct sbp2_target *tgt = lu->tgt;
 877         struct fw_device *device = fw_device(tgt->unit->device.parent);
 878         struct Scsi_Host *shost;
 879         struct scsi_device *sdev;
 880         struct sbp2_login_response response;
 881         int generation, node_id, local_node_id;
 882
 883         if (fw_device_is_shutdown(device))
 884                 goto out;
 885
 886         generation    = device->generation;
 887         smp_rmb();    /* node_id must not be older than generation */
 888         node_id       = device->node_id;
 889         local_node_id = device->card->node_id;
 890
 891         /* If this is a re-login attempt, log out, or we might be rejected. */
 892         if (lu->has_sdev)
 893                 sbp2_send_management_orb(lu, device->node_id, generation,
 894                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 895
 896         if (sbp2_send_management_orb(lu, node_id, generation,
 897                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 898                 if (lu->retries++ < 5) {
 899                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 900                 } else {
 901                         fw_error("%s: failed to login to LUN %04x\n",
 902                                  tgt->bus_id, lu->lun);
 903                         /* Let any waiting I/O fail from now on. */
 904                         sbp2_unblock(lu->tgt);
 905                 }
 906                 goto out;
 907         }
 908
 909         tgt->node_id      = node_id;
 910         tgt->address_high = local_node_id << 16;
 911         sbp2_set_generation(lu, generation);
 912
 913         lu->command_block_agent_address =
 914                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 915                       << 32) | be32_to_cpu(response.command_block_agent.low);
 916         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 917
 918         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 919                   tgt->bus_id, lu->lun, lu->retries);
 920
 921         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 922         sbp2_set_busy_timeout(lu);
 923
 924         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 925         sbp2_agent_reset(lu);
 926
 927         /* This was a re-login. */
 928         if (lu->has_sdev) {
 929                 sbp2_cancel_orbs(lu);
 930                 sbp2_conditionally_unblock(lu);
 931                 goto out;
 932         }
 933
 934         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 935                 ssleep(SBP2_INQUIRY_DELAY);
 936
 937         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 938         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 939         /*
 940          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 941          * Therefore __scsi_add_device() will get into trouble if a bus reset
 942          * happens in parallel.  It will either fail or leave us with an
 943          * unusable sdev.  As a workaround we check for this and retry the
 944          * whole login and SCSI probing.
 945          */
 946
 947         /* Reported error during __scsi_add_device() */
 948         if (IS_ERR(sdev))
 949                 goto out_logout_login;
 950
 951         /* Unreported error during __scsi_add_device() */
 952         smp_rmb(); /* get current card generation */
 953         if (generation != device->card->generation) {
 954                 scsi_remove_device(sdev);
 955                 scsi_device_put(sdev);
 956                 goto out_logout_login;
 957         }
 958
 959         /* No error during __scsi_add_device() */
 960         lu->has_sdev = true;
 961         scsi_device_put(sdev);
 962         sbp2_allow_block(lu);
 963         goto out;
 964
 965  out_logout_login:
 966         smp_rmb(); /* generation may have changed */
 967         generation = device->generation;
 968         smp_rmb(); /* node_id must not be older than generation */
 969
 970         sbp2_send_management_orb(lu, device->node_id, generation,
 971                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 972         /*
 973          * If a bus reset happened, sbp2_update will have requeued
 974          * lu->work already.  Reset the work from reconnect to login.
 975          */
 976         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 977  out:
 978         sbp2_target_put(tgt);
 979 }
 980
 981 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 982 {
 983         struct sbp2_logical_unit *lu;
 984
 985         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 986         if (!lu)
 987                 return -ENOMEM;
 988
 989         lu->address_handler.length           = 0x100;
 990         lu->address_handler.address_callback = sbp2_status_write;
 991         lu->address_handler.callback_data    = lu;
 992
 993         if (fw_core_add_address_handler(&lu->address_handler,
 994                                         &fw_high_memory_region) < 0) {
 995                 kfree(lu);
 996                 return -ENOMEM;
 997         }
 998
 999         lu->tgt      = tgt;
1000         lu->lun      = lun_entry & 0xffff;
1001         lu->login_id = INVALID_LOGIN_ID;
1002         lu->retries  = 0;
1003         lu->has_sdev = false;
1004         lu->blocked  = false;
1005         ++tgt->dont_block;
1006         INIT_LIST_HEAD(&lu->orb_list);
1007         INIT_DELAYED_WORK(&lu->work, sbp2_login);
1008
1009         list_add_tail(&lu->link, &tgt->lu_list);
1010         return 0;
1011 }
1012
1013 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
1014 {
1015         struct fw_csr_iterator ci;
1016         int key, value;
1017
1018         fw_csr_iterator_init(&ci, directory);
1019         while (fw_csr_iterator_next(&ci, &key, &value))
1020                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1021                     sbp2_add_logical_unit(tgt, value) < 0)
1022                         return -ENOMEM;
1023         return 0;
1024 }
1025
1026 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
1027                               u32 *model, u32 *firmware_revision)
1028 {
1029         struct fw_csr_iterator ci;
1030         int key, value;
1031         unsigned int timeout;
1032
1033         fw_csr_iterator_init(&ci, directory);
1034         while (fw_csr_iterator_next(&ci, &key, &value)) {
1035                 switch (key) {
1036
1037                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1038                         tgt->management_agent_address =
1039                                         CSR_REGISTER_BASE + 4 * value;
1040                         break;
1041
1042                 case CSR_DIRECTORY_ID:
1043                         tgt->directory_id = value;
1044                         break;
1045
1046                 case CSR_MODEL:
1047                         *model = value;
1048                         break;
1049
1050                 case SBP2_CSR_FIRMWARE_REVISION:
1051                         *firmware_revision = value;
1052                         break;
1053
1054                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1055                         /* the timeout value is stored in 500ms units */
1056                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1057                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1058                         tgt->mgt_orb_timeout =
1059                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1060
1061                         if (timeout > tgt->mgt_orb_timeout)
1062                                 fw_notify("%s: config rom contains %ds "
1063                                           "management ORB timeout, limiting "
1064                                           "to %ds\n", tgt->bus_id,
1065                                           timeout / 1000,
1066                                           tgt->mgt_orb_timeout / 1000);
1067                         break;
1068
1069                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1070                         if (sbp2_add_logical_unit(tgt, value) < 0)
1071                                 return -ENOMEM;
1072                         break;
1073
1074                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1075                         /* Adjust for the increment in the iterator */
1076                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1077                                 return -ENOMEM;
1078                         break;
1079                 }
1080         }
1081         return 0;
1082 }
1083
1084 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1085                                   u32 firmware_revision)
1086 {
1087         int i;
1088         unsigned int w = sbp2_param_workarounds;
1089
1090         if (w)
1091                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1092                           "if you need the workarounds parameter for %s\n",
1093                           tgt->bus_id);
1094
1095         if (w & SBP2_WORKAROUND_OVERRIDE)
1096                 goto out;
1097
1098         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1099
1100                 if (sbp2_workarounds_table[i].firmware_revision !=
1101                     (firmware_revision & 0xffffff00))
1102                         continue;
1103
1104                 if (sbp2_workarounds_table[i].model != model &&
1105                     sbp2_workarounds_table[i].model != ~0)
1106                         continue;
1107
1108                 w |= sbp2_workarounds_table[i].workarounds;
1109                 break;
1110         }
1111  out:
1112         if (w)
1113                 fw_notify("Workarounds for %s: 0x%x "
1114                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1115                           tgt->bus_id, w, firmware_revision, model);
1116         tgt->workarounds = w;
1117 }
1118
1119 static struct scsi_host_template scsi_driver_template;
1120
1121 static int sbp2_probe(struct device *dev)
1122 {
1123         struct fw_unit *unit = fw_unit(dev);
1124         struct fw_device *device = fw_device(unit->device.parent);
1125         struct sbp2_target *tgt;
1126         struct sbp2_logical_unit *lu;
1127         struct Scsi_Host *shost;
1128         u32 model, firmware_revision;
1129
1130         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1131                 BUG_ON(dma_set_max_seg_size(device->card->device,
1132                                             SBP2_MAX_SEG_SIZE));
1133
1134         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1135         if (shost == NULL)
1136                 return -ENOMEM;
1137
1138         tgt = (struct sbp2_target *)shost->hostdata;
1139         unit->device.driver_data = tgt;
1140         tgt->unit = unit;
1141         kref_init(&tgt->kref);
1142         INIT_LIST_HEAD(&tgt->lu_list);
1143         tgt->bus_id = dev_name(&unit->device);
1144         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1145
1146         if (fw_device_enable_phys_dma(device) < 0)
1147                 goto fail_shost_put;
1148
1149         if (scsi_add_host(shost, &unit->device) < 0)
1150                 goto fail_shost_put;
1151
1152         fw_device_get(device);
1153         fw_unit_get(unit);
1154
1155         /* Initialize to values that won't match anything in our table. */
1156         firmware_revision = 0xff000000;
1157         model = 0xff000000;
1158
1159         /* implicit directory ID */
1160         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1161                              + CSR_CONFIG_ROM) & 0xffffff;
1162
1163         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1164                                &firmware_revision) < 0)
1165                 goto fail_tgt_put;
1166
1167         sbp2_init_workarounds(tgt, model, firmware_revision);
1168
1169         /* Do the login in a workqueue so we can easily reschedule retries. */
1170         list_for_each_entry(lu, &tgt->lu_list, link)
1171                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1172         return 0;
1173
1174  fail_tgt_put:
1175         sbp2_target_put(tgt);
1176         return -ENOMEM;
1177
1178  fail_shost_put:
1179         scsi_host_put(shost);
1180         return -ENOMEM;
1181 }
1182
1183 static int sbp2_remove(struct device *dev)
1184 {
1185         struct fw_unit *unit = fw_unit(dev);
1186         struct sbp2_target *tgt = unit->device.driver_data;
1187
1188         sbp2_target_put(tgt);
1189         return 0;
1190 }
1191
1192 static void sbp2_reconnect(struct work_struct *work)
1193 {
1194         struct sbp2_logical_unit *lu =
1195                 container_of(work, struct sbp2_logical_unit, work.work);
1196         struct sbp2_target *tgt = lu->tgt;
1197         struct fw_device *device = fw_device(tgt->unit->device.parent);
1198         int generation, node_id, local_node_id;
1199
1200         if (fw_device_is_shutdown(device))
1201                 goto out;
1202
1203         generation    = device->generation;
1204         smp_rmb();    /* node_id must not be older than generation */
1205         node_id       = device->node_id;
1206         local_node_id = device->card->node_id;
1207
1208         if (sbp2_send_management_orb(lu, node_id, generation,
1209                                      SBP2_RECONNECT_REQUEST,
1210                                      lu->login_id, NULL) < 0) {
1211                 /*
1212                  * If reconnect was impossible even though we are in the
1213                  * current generation, fall back and try to log in again.
1214                  *
1215                  * We could check for "Function rejected" status, but
1216                  * looking at the bus generation as simpler and more general.
1217                  */
1218                 smp_rmb(); /* get current card generation */
1219                 if (generation == device->card->generation ||
1220                     lu->retries++ >= 5) {
1221                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1222                         lu->retries = 0;
1223                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1224                 }
1225                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1226                 goto out;
1227         }
1228
1229         tgt->node_id      = node_id;
1230         tgt->address_high = local_node_id << 16;
1231         sbp2_set_generation(lu, generation);
1232
1233         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1234                   tgt->bus_id, lu->lun, lu->retries);
1235
1236         sbp2_agent_reset(lu);
1237         sbp2_cancel_orbs(lu);
1238         sbp2_conditionally_unblock(lu);
1239  out:
1240         sbp2_target_put(tgt);
1241 }
1242
1243 static void sbp2_update(struct fw_unit *unit)
1244 {
1245         struct sbp2_target *tgt = unit->device.driver_data;
1246         struct sbp2_logical_unit *lu;
1247
1248         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1249
1250         /*
1251          * Fw-core serializes sbp2_update() against sbp2_remove().
1252          * Iteration over tgt->lu_list is therefore safe here.
1253          */
1254         list_for_each_entry(lu, &tgt->lu_list, link) {
1255                 sbp2_conditionally_block(lu);
1256                 lu->retries = 0;
1257                 sbp2_queue_work(lu, 0);
1258         }
1259 }
1260
1261 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1262 #define SBP2_SW_VERSION_ENTRY   0x00010483
1263
1264 static const struct fw_device_id sbp2_id_table[] = {
1265         {
1266                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1267                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1268                 .version      = SBP2_SW_VERSION_ENTRY,
1269         },
1270         { }
1271 };
1272
1273 static struct fw_driver sbp2_driver = {
1274         .driver   = {
1275                 .owner  = THIS_MODULE,
1276                 .name   = sbp2_driver_name,
1277                 .bus    = &fw_bus_type,
1278                 .probe  = sbp2_probe,
1279                 .remove = sbp2_remove,
1280         },
1281         .update   = sbp2_update,
1282         .id_table = sbp2_id_table,
1283 };
1284
1285 static unsigned int
1286 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1287 {
1288         int sam_status;
1289
1290         sense_data[0] = 0x70;
1291         sense_data[1] = 0x0;
1292         sense_data[2] = sbp2_status[1];
1293         sense_data[3] = sbp2_status[4];
1294         sense_data[4] = sbp2_status[5];
1295         sense_data[5] = sbp2_status[6];
1296         sense_data[6] = sbp2_status[7];
1297         sense_data[7] = 10;
1298         sense_data[8] = sbp2_status[8];
1299         sense_data[9] = sbp2_status[9];
1300         sense_data[10] = sbp2_status[10];
1301         sense_data[11] = sbp2_status[11];
1302         sense_data[12] = sbp2_status[2];
1303         sense_data[13] = sbp2_status[3];
1304         sense_data[14] = sbp2_status[12];
1305         sense_data[15] = sbp2_status[13];
1306
1307         sam_status = sbp2_status[0] & 0x3f;
1308
1309         switch (sam_status) {
1310         case SAM_STAT_GOOD:
1311         case SAM_STAT_CHECK_CONDITION:
1312         case SAM_STAT_CONDITION_MET:
1313         case SAM_STAT_BUSY:
1314         case SAM_STAT_RESERVATION_CONFLICT:
1315         case SAM_STAT_COMMAND_TERMINATED:
1316                 return DID_OK << 16 | sam_status;
1317
1318         default:
1319                 return DID_ERROR << 16;
1320         }
1321 }
1322
1323 static void
1324 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1325 {
1326         struct sbp2_command_orb *orb =
1327                 container_of(base_orb, struct sbp2_command_orb, base);
1328         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1329         int result;
1330
1331         if (status != NULL) {
1332                 if (STATUS_GET_DEAD(*status))
1333                         sbp2_agent_reset_no_wait(orb->lu);
1334
1335                 switch (STATUS_GET_RESPONSE(*status)) {
1336                 case SBP2_STATUS_REQUEST_COMPLETE:
1337                         result = DID_OK << 16;
1338                         break;
1339                 case SBP2_STATUS_TRANSPORT_FAILURE:
1340                         result = DID_BUS_BUSY << 16;
1341                         break;
1342                 case SBP2_STATUS_ILLEGAL_REQUEST:
1343                 case SBP2_STATUS_VENDOR_DEPENDENT:
1344                 default:
1345                         result = DID_ERROR << 16;
1346                         break;
1347                 }
1348
1349                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1350                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1351                                                            orb->cmd->sense_buffer);
1352         } else {
1353                 /*
1354                  * If the orb completes with status == NULL, something
1355                  * went wrong, typically a bus reset happened mid-orb
1356                  * or when sending the write (less likely).
1357                  */
1358                 result = DID_BUS_BUSY << 16;
1359                 sbp2_conditionally_block(orb->lu);
1360         }
1361
1362         dma_unmap_single(device->card->device, orb->base.request_bus,
1363                          sizeof(orb->request), DMA_TO_DEVICE);
1364
1365         if (scsi_sg_count(orb->cmd) > 0)
1366                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1367                              scsi_sg_count(orb->cmd),
1368                              orb->cmd->sc_data_direction);
1369
1370         if (orb->page_table_bus != 0)
1371                 dma_unmap_single(device->card->device, orb->page_table_bus,
1372                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1373
1374         orb->cmd->result = result;
1375         orb->done(orb->cmd);
1376 }
1377
1378 static int
1379 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1380                      struct sbp2_logical_unit *lu)
1381 {
1382         struct scatterlist *sg = scsi_sglist(orb->cmd);
1383         int i, n;
1384
1385         n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1386                        orb->cmd->sc_data_direction);
1387         if (n == 0)
1388                 goto fail;
1389
1390         /*
1391          * Handle the special case where there is only one element in
1392          * the scatter list by converting it to an immediate block
1393          * request. This is also a workaround for broken devices such
1394          * as the second generation iPod which doesn't support page
1395          * tables.
1396          */
1397         if (n == 1) {
1398                 orb->request.data_descriptor.high =
1399                         cpu_to_be32(lu->tgt->address_high);
1400                 orb->request.data_descriptor.low  =
1401                         cpu_to_be32(sg_dma_address(sg));
1402                 orb->request.misc |=
1403                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1404                 return 0;
1405         }
1406
1407         for_each_sg(sg, sg, n, i) {
1408                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1409                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1410         }
1411
1412         orb->page_table_bus =
1413                 dma_map_single(device->card->device, orb->page_table,
1414                                sizeof(orb->page_table), DMA_TO_DEVICE);
1415         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1416                 goto fail_page_table;
1417
1418         /*
1419          * The data_descriptor pointer is the one case where we need
1420          * to fill in the node ID part of the address.  All other
1421          * pointers assume that the data referenced reside on the
1422          * initiator (i.e. us), but data_descriptor can refer to data
1423          * on other nodes so we need to put our ID in descriptor.high.
1424          */
1425         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1426         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1427         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1428                                          COMMAND_ORB_DATA_SIZE(n));
1429
1430         return 0;
1431
1432  fail_page_table:
1433         dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1434                      scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
1435  fail:
1436         return -ENOMEM;
1437 }
1438
1439 /* SCSI stack integration */
1440
1441 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1442 {
1443         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1444         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1445         struct sbp2_command_orb *orb;
1446         unsigned int max_payload;
1447         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1448
1449         /*
1450          * Bidirectional commands are not yet implemented, and unknown
1451          * transfer direction not handled.
1452          */
1453         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1454                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1455                 cmd->result = DID_ERROR << 16;
1456                 done(cmd);
1457                 return 0;
1458         }
1459
1460         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1461         if (orb == NULL) {
1462                 fw_notify("failed to alloc orb\n");
1463                 return SCSI_MLQUEUE_HOST_BUSY;
1464         }
1465
1466         /* Initialize rcode to something not RCODE_COMPLETE. */
1467         orb->base.rcode = -1;
1468         kref_init(&orb->base.kref);
1469
1470         orb->lu   = lu;
1471         orb->done = done;
1472         orb->cmd  = cmd;
1473
1474         orb->request.next.high   = cpu_to_be32(SBP2_ORB_NULL);
1475         /*
1476          * At speed 100 we can do 512 bytes per packet, at speed 200,
1477          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1478          * specifies the max payload size as 2 ^ (max_payload + 2), so
1479          * if we set this to max_speed + 7, we get the right value.
1480          */
1481         max_payload = min(device->max_speed + 7,
1482                           device->card->max_receive - 1);
1483         orb->request.misc = cpu_to_be32(
1484                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1485                 COMMAND_ORB_SPEED(device->max_speed) |
1486                 COMMAND_ORB_NOTIFY);
1487
1488         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1489                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1490
1491         generation = device->generation;
1492         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1493
1494         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1495                 goto out;
1496
1497         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1498
1499         orb->base.callback = complete_command_orb;
1500         orb->base.request_bus =
1501                 dma_map_single(device->card->device, &orb->request,
1502                                sizeof(orb->request), DMA_TO_DEVICE);
1503         if (dma_mapping_error(device->card->device, orb->base.request_bus))
1504                 goto out;
1505
1506         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1507                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1508         retval = 0;
1509  out:
1510         kref_put(&orb->base.kref, free_orb);
1511         return retval;
1512 }
1513
1514 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1515 {
1516         struct sbp2_logical_unit *lu = sdev->hostdata;
1517
1518         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1519         if (!lu)
1520                 return -ENOSYS;
1521
1522         sdev->allow_restart = 1;
1523
1524         /* SBP-2 requires quadlet alignment of the data buffers. */
1525         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1526
1527         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1528                 sdev->inquiry_len = 36;
1529
1530         return 0;
1531 }
1532
1533 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1534 {
1535         struct sbp2_logical_unit *lu = sdev->hostdata;
1536
1537         sdev->use_10_for_rw = 1;
1538
1539         if (sbp2_param_exclusive_login)
1540                 sdev->manage_start_stop = 1;
1541
1542         if (sdev->type == TYPE_ROM)
1543                 sdev->use_10_for_ms = 1;
1544
1545         if (sdev->type == TYPE_DISK &&
1546             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1547                 sdev->skip_ms_page_8 = 1;
1548
1549         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1550                 sdev->fix_capacity = 1;
1551
1552         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1553                 sdev->start_stop_pwr_cond = 1;
1554
1555         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1556                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1557
1558         blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
1559
1560         return 0;
1561 }
1562
1563 /*
1564  * Called by scsi stack when something has really gone wrong.  Usually
1565  * called when a command has timed-out for some reason.
1566  */
1567 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1568 {
1569         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1570
1571         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1572         sbp2_agent_reset(lu);
1573         sbp2_cancel_orbs(lu);
1574
1575         return SUCCESS;
1576 }
1577
1578 /*
1579  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1580  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1581  *
1582  * This is the concatenation of target port identifier and logical unit
1583  * identifier as per SAM-2...SAM-4 annex A.
1584  */
1585 static ssize_t
1586 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1587                             char *buf)
1588 {
1589         struct scsi_device *sdev = to_scsi_device(dev);
1590         struct sbp2_logical_unit *lu;
1591
1592         if (!sdev)
1593                 return 0;
1594
1595         lu = sdev->hostdata;
1596
1597         return sprintf(buf, "%016llx:%06x:%04x\n",
1598                         (unsigned long long)lu->tgt->guid,
1599                         lu->tgt->directory_id, lu->lun);
1600 }
1601
1602 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1603
1604 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1605         &dev_attr_ieee1394_id,
1606         NULL
1607 };
1608
1609 static struct scsi_host_template scsi_driver_template = {
1610         .module                 = THIS_MODULE,
1611         .name                   = "SBP-2 IEEE-1394",
1612         .proc_name              = sbp2_driver_name,
1613         .queuecommand           = sbp2_scsi_queuecommand,
1614         .slave_alloc            = sbp2_scsi_slave_alloc,
1615         .slave_configure        = sbp2_scsi_slave_configure,
1616         .eh_abort_handler       = sbp2_scsi_abort,
1617         .this_id                = -1,
1618         .sg_tablesize           = SG_ALL,
1619         .use_clustering         = ENABLE_CLUSTERING,
1620         .cmd_per_lun            = 1,
1621         .can_queue              = 1,
1622         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1623 };
1624
1625 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1626 MODULE_DESCRIPTION("SCSI over IEEE1394");
1627 MODULE_LICENSE("GPL");
1628 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1629
1630 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1631 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1632 MODULE_ALIAS("sbp2");
1633 #endif
1634
1635 static int __init sbp2_init(void)
1636 {
1637         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1638         if (!sbp2_wq)
1639                 return -ENOMEM;
1640
1641         return driver_register(&sbp2_driver.driver);
1642 }
1643
1644 static void __exit sbp2_cleanup(void)
1645 {
1646         driver_unregister(&sbp2_driver.driver);
1647         destroy_workqueue(sbp2_wq);
1648 }
1649
1650 module_init(sbp2_init);
1651 module_exit(sbp2_cleanup);