drivers/firewire/sbp2.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * SBP2 driver (SCSI over IEEE1394)
   4  *
   5  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   6  */
   7
   8 /*
   9  * The basic structure of this driver is based on the old storage driver,
  10  * drivers/ieee1394/sbp2.c, originally written by
  11  *     James Goodwin <jamesg@filanet.com>
  12  * with later contributions and ongoing maintenance from
  13  *     Ben Collins <bcollins@debian.org>,
  14  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  15  * and many others.
  16  */
  17
  18 #include <linux/blkdev.h>
  19 #include <linux/bug.h>
  20 #include <linux/completion.h>
  21 #include <linux/delay.h>
  22 #include <linux/device.h>
  23 #include <linux/dma-mapping.h>
  24 #include <linux/firewire.h>
  25 #include <linux/firewire-constants.h>
  26 #include <linux/init.h>
  27 #include <linux/jiffies.h>
  28 #include <linux/kernel.h>
  29 #include <linux/kref.h>
  30 #include <linux/list.h>
  31 #include <linux/mod_devicetable.h>
  32 #include <linux/module.h>
  33 #include <linux/moduleparam.h>
  34 #include <linux/scatterlist.h>
  35 #include <linux/slab.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/string.h>
  38 #include <linux/stringify.h>
  39 #include <linux/workqueue.h>
  40
  41 #include <asm/byteorder.h>
  42
  43 #include <scsi/scsi.h>
  44 #include <scsi/scsi_cmnd.h>
  45 #include <scsi/scsi_device.h>
  46 #include <scsi/scsi_host.h>
  47
  48 /*
  49  * So far only bridges from Oxford Semiconductor are known to support
  50  * concurrent logins. Depending on firmware, four or two concurrent logins
  51  * are possible on OXFW911 and newer Oxsemi bridges.
  52  *
  53  * Concurrent logins are useful together with cluster filesystems.
  54  */
  55 static bool sbp2_param_exclusive_login = 1;
  56 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  57 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  58                  "(default = Y, use N for concurrent initiators)");
  59
  60 /*
  61  * Flags for firmware oddities
  62  *
  63  * - 128kB max transfer
  64  *   Limit transfer size. Necessary for some old bridges.
  65  *
  66  * - 36 byte inquiry
  67  *   When scsi_mod probes the device, let the inquiry command look like that
  68  *   from MS Windows.
  69  *
  70  * - skip mode page 8
  71  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  72  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  73  *
  74  * - fix capacity
  75  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  76  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  77  *   Don't use this with devices which don't have this bug.
  78  *
  79  * - delay inquiry
  80  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  81  *
  82  * - power condition
  83  *   Set the power condition field in the START STOP UNIT commands sent by
  84  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  85  *   Some disks need this to spin down or to resume properly.
  86  *
  87  * - override internal blacklist
  88  *   Instead of adding to the built-in blacklist, use only the workarounds
  89  *   specified in the module load parameter.
  90  *   Useful if a blacklist entry interfered with a non-broken device.
  91  */
  92 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
  93 #define SBP2_WORKAROUND_INQUIRY_36      0x2
  94 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
  95 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
  96 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
  97 #define SBP2_INQUIRY_DELAY              12
  98 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
  99 #define SBP2_WORKAROUND_OVERRIDE        0x100
 100
 101 static int sbp2_param_workarounds;
 102 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 103 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 104         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 105         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 106         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 107         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 108         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 109         ", set power condition in start stop unit = "
 110                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 111         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 112         ", or a combination)");
 113
 114 /*
 115  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 116  * and one struct scsi_device per sbp2_logical_unit.
 117  */
 118 struct sbp2_logical_unit {
 119         struct sbp2_target *tgt;
 120         struct list_head link;
 121         struct fw_address_handler address_handler;
 122         struct list_head orb_list;
 123
 124         u64 command_block_agent_address;
 125         u16 lun;
 126         int login_id;
 127
 128         /*
 129          * The generation is updated once we've logged in or reconnected
 130          * to the logical unit.  Thus, I/O to the device will automatically
 131          * fail and get retried if it happens in a window where the device
 132          * is not ready, e.g. after a bus reset but before we reconnect.
 133          */
 134         int generation;
 135         int retries;
 136         work_func_t workfn;
 137         struct delayed_work work;
 138         bool has_sdev;
 139         bool blocked;
 140 };
 141
 142 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 143 {
 144         queue_delayed_work(fw_workqueue, &lu->work, delay);
 145 }
 146
 147 /*
 148  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 149  * and one struct Scsi_Host per sbp2_target.
 150  */
 151 struct sbp2_target {
 152         struct fw_unit *unit;
 153         struct list_head lu_list;
 154
 155         u64 management_agent_address;
 156         u64 guid;
 157         int directory_id;
 158         int node_id;
 159         int address_high;
 160         unsigned int workarounds;
 161         unsigned int mgt_orb_timeout;
 162         unsigned int max_payload;
 163
 164         spinlock_t lock;
 165         int dont_block; /* counter for each logical unit */
 166         int blocked;    /* ditto */
 167 };
 168
 169 static struct fw_device *target_parent_device(struct sbp2_target *tgt)
 170 {
 171         return fw_parent_device(tgt->unit);
 172 }
 173
 174 static const struct device *tgt_dev(const struct sbp2_target *tgt)
 175 {
 176         return &tgt->unit->device;
 177 }
 178
 179 static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
 180 {
 181         return &lu->tgt->unit->device;
 182 }
 183
 184 /* Impossible login_id, to detect logout attempt before successful login */
 185 #define INVALID_LOGIN_ID 0x10000
 186
 187 #define SBP2_ORB_TIMEOUT                2000U           /* Timeout in ms */
 188 #define SBP2_ORB_NULL                   0x80000000
 189 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 190 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 191
 192 /*
 193  * There is no transport protocol limit to the CDB length,  but we implement
 194  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
 195  */
 196 #define SBP2_MAX_CDB_SIZE               16
 197
 198 /*
 199  * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
 200  * for compatibility with earlier versions of this driver.
 201  */
 202 #define SBP2_MAX_SEG_SIZE               0xfffc
 203
 204 /* Unit directory keys */
 205 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 206 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 207 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 208 #define SBP2_CSR_UNIT_UNIQUE_ID         0x8d
 209 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 210
 211 /* Management orb opcodes */
 212 #define SBP2_LOGIN_REQUEST              0x0
 213 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 214 #define SBP2_RECONNECT_REQUEST          0x3
 215 #define SBP2_SET_PASSWORD_REQUEST       0x4
 216 #define SBP2_LOGOUT_REQUEST             0x7
 217 #define SBP2_ABORT_TASK_REQUEST         0xb
 218 #define SBP2_ABORT_TASK_SET             0xc
 219 #define SBP2_LOGICAL_UNIT_RESET         0xe
 220 #define SBP2_TARGET_RESET_REQUEST       0xf
 221
 222 /* Offsets for command block agent registers */
 223 #define SBP2_AGENT_STATE                0x00
 224 #define SBP2_AGENT_RESET                0x04
 225 #define SBP2_ORB_POINTER                0x08
 226 #define SBP2_DOORBELL                   0x10
 227 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 228
 229 /* Status write response codes */
 230 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 231 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 232 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 233 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 234
 235 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 236 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 237 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 238 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 239 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 240 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 241 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 242 #define STATUS_GET_DATA(v)              ((v).data)
 243
 244 struct sbp2_status {
 245         u32 status;
 246         u32 orb_low;
 247         u8 data[24];
 248 };
 249
 250 struct sbp2_pointer {
 251         __be32 high;
 252         __be32 low;
 253 };
 254
 255 struct sbp2_orb {
 256         struct fw_transaction t;
 257         struct kref kref;
 258         dma_addr_t request_bus;
 259         int rcode;
 260         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 261         struct sbp2_logical_unit *lu;
 262         struct list_head link;
 263 };
 264
 265 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 266 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 267 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 268 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 269 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 270 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 271
 272 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 273 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 274
 275 struct sbp2_management_orb {
 276         struct sbp2_orb base;
 277         struct {
 278                 struct sbp2_pointer password;
 279                 struct sbp2_pointer response;
 280                 __be32 misc;
 281                 __be32 length;
 282                 struct sbp2_pointer status_fifo;
 283         } request;
 284         __be32 response[4];
 285         dma_addr_t response_bus;
 286         struct completion done;
 287         struct sbp2_status status;
 288 };
 289
 290 struct sbp2_login_response {
 291         __be32 misc;
 292         struct sbp2_pointer command_block_agent;
 293         __be32 reconnect_hold;
 294 };
 295 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 296 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 297 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 298 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 299 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 300 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 301 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 302 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 303
 304 struct sbp2_command_orb {
 305         struct sbp2_orb base;
 306         struct {
 307                 struct sbp2_pointer next;
 308                 struct sbp2_pointer data_descriptor;
 309                 __be32 misc;
 310                 u8 command_block[SBP2_MAX_CDB_SIZE];
 311         } request;
 312         struct scsi_cmnd *cmd;
 313
 314         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 315         dma_addr_t page_table_bus;
 316 };
 317
 318 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 319 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 320
 321 /*
 322  * List of devices with known bugs.
 323  *
 324  * The firmware_revision field, masked with 0xffff00, is the best
 325  * indicator for the type of bridge chip of a device.  It yields a few
 326  * false positives but this did not break correctly behaving devices
 327  * so far.
 328  */
 329 static const struct {
 330         u32 firmware_revision;
 331         u32 model;
 332         unsigned int workarounds;
 333 } sbp2_workarounds_table[] = {
 334         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 335                 .firmware_revision      = 0x002800,
 336                 .model                  = 0x001010,
 337                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 338                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 339                                           SBP2_WORKAROUND_POWER_CONDITION,
 340         },
 341         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 342                 .firmware_revision      = 0x002800,
 343                 .model                  = 0x000000,
 344                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 345         },
 346         /* Initio bridges, actually only needed for some older ones */ {
 347                 .firmware_revision      = 0x000200,
 348                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 349                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 350         },
 351         /* PL-3507 bridge with Prolific firmware */ {
 352                 .firmware_revision      = 0x012800,
 353                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 354                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 355         },
 356         /* Symbios bridge */ {
 357                 .firmware_revision      = 0xa0b800,
 358                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 359                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 360         },
 361         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 362                 .firmware_revision      = 0x002600,
 363                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 364                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 365         },
 366         /*
 367          * iPod 2nd generation: needs 128k max transfer size workaround
 368          * iPod 3rd generation: needs fix capacity workaround
 369          */
 370         {
 371                 .firmware_revision      = 0x0a2700,
 372                 .model                  = 0x000000,
 373                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 374                                           SBP2_WORKAROUND_FIX_CAPACITY,
 375         },
 376         /* iPod 4th generation */ {
 377                 .firmware_revision      = 0x0a2700,
 378                 .model                  = 0x000021,
 379                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 380         },
 381         /* iPod mini */ {
 382                 .firmware_revision      = 0x0a2700,
 383                 .model                  = 0x000022,
 384                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 385         },
 386         /* iPod mini */ {
 387                 .firmware_revision      = 0x0a2700,
 388                 .model                  = 0x000023,
 389                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 390         },
 391         /* iPod Photo */ {
 392                 .firmware_revision      = 0x0a2700,
 393                 .model                  = 0x00007e,
 394                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 395         }
 396 };
 397
 398 static void free_orb(struct kref *kref)
 399 {
 400         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 401
 402         kfree(orb);
 403 }
 404
 405 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 406                               int tcode, int destination, int source,
 407                               int generation, unsigned long long offset,
 408                               void *payload, size_t length, void *callback_data)
 409 {
 410         struct sbp2_logical_unit *lu = callback_data;
 411         struct sbp2_orb *orb = NULL, *iter;
 412         struct sbp2_status status;
 413         unsigned long flags;
 414
 415         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 416             length < 8 || length > sizeof(status)) {
 417                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 418                 return;
 419         }
 420
 421         status.status  = be32_to_cpup(payload);
 422         status.orb_low = be32_to_cpup(payload + 4);
 423         memset(status.data, 0, sizeof(status.data));
 424         if (length > 8)
 425                 memcpy(status.data, payload + 8, length - 8);
 426
 427         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 428                 dev_notice(lu_dev(lu),
 429                            "non-ORB related status write, not handled\n");
 430                 fw_send_response(card, request, RCODE_COMPLETE);
 431                 return;
 432         }
 433
 434         /* Lookup the orb corresponding to this status write. */
 435         spin_lock_irqsave(&lu->tgt->lock, flags);
 436         list_for_each_entry(iter, &lu->orb_list, link) {
 437                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 438                     STATUS_GET_ORB_LOW(status) == iter->request_bus) {
 439                         iter->rcode = RCODE_COMPLETE;
 440                         list_del(&iter->link);
 441                         orb = iter;
 442                         break;
 443                 }
 444         }
 445         spin_unlock_irqrestore(&lu->tgt->lock, flags);
 446
 447         if (orb) {
 448                 orb->callback(orb, &status);
 449                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 450         } else {
 451                 dev_err(lu_dev(lu), "status write for unknown ORB\n");
 452         }
 453
 454         fw_send_response(card, request, RCODE_COMPLETE);
 455 }
 456
 457 static void complete_transaction(struct fw_card *card, int rcode,
 458                                  void *payload, size_t length, void *data)
 459 {
 460         struct sbp2_orb *orb = data;
 461         unsigned long flags;
 462
 463         /*
 464          * This is a little tricky.  We can get the status write for
 465          * the orb before we get this callback.  The status write
 466          * handler above will assume the orb pointer transaction was
 467          * successful and set the rcode to RCODE_COMPLETE for the orb.
 468          * So this callback only sets the rcode if it hasn't already
 469          * been set and only does the cleanup if the transaction
 470          * failed and we didn't already get a status write.
 471          */
 472         spin_lock_irqsave(&orb->lu->tgt->lock, flags);
 473
 474         if (orb->rcode == -1)
 475                 orb->rcode = rcode;
 476         if (orb->rcode != RCODE_COMPLETE) {
 477                 list_del(&orb->link);
 478                 spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 479
 480                 orb->callback(orb, NULL);
 481                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 482         } else {
 483                 spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 484         }
 485
 486         kref_put(&orb->kref, free_orb); /* transaction callback reference */
 487 }
 488
 489 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 490                           int node_id, int generation, u64 offset)
 491 {
 492         struct fw_device *device = target_parent_device(lu->tgt);
 493         struct sbp2_pointer orb_pointer;
 494         unsigned long flags;
 495
 496         orb_pointer.high = 0;
 497         orb_pointer.low = cpu_to_be32(orb->request_bus);
 498
 499         orb->lu = lu;
 500         spin_lock_irqsave(&lu->tgt->lock, flags);
 501         list_add_tail(&orb->link, &lu->orb_list);
 502         spin_unlock_irqrestore(&lu->tgt->lock, flags);
 503
 504         kref_get(&orb->kref); /* transaction callback reference */
 505         kref_get(&orb->kref); /* orb callback reference */
 506
 507         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 508                         node_id, generation, device->max_speed, offset,
 509                         &orb_pointer, 8, complete_transaction, orb);
 510 }
 511
 512 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 513 {
 514         struct fw_device *device = target_parent_device(lu->tgt);
 515         struct sbp2_orb *orb, *next;
 516         struct list_head list;
 517         int retval = -ENOENT;
 518
 519         INIT_LIST_HEAD(&list);
 520         spin_lock_irq(&lu->tgt->lock);
 521         list_splice_init(&lu->orb_list, &list);
 522         spin_unlock_irq(&lu->tgt->lock);
 523
 524         list_for_each_entry_safe(orb, next, &list, link) {
 525                 retval = 0;
 526                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 527                         continue;
 528
 529                 orb->rcode = RCODE_CANCELLED;
 530                 orb->callback(orb, NULL);
 531                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 532         }
 533
 534         return retval;
 535 }
 536
 537 static void complete_management_orb(struct sbp2_orb *base_orb,
 538                                     struct sbp2_status *status)
 539 {
 540         struct sbp2_management_orb *orb =
 541                 container_of(base_orb, struct sbp2_management_orb, base);
 542
 543         if (status)
 544                 memcpy(&orb->status, status, sizeof(*status));
 545         complete(&orb->done);
 546 }
 547
 548 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 549                                     int generation, int function,
 550                                     int lun_or_login_id, void *response)
 551 {
 552         struct fw_device *device = target_parent_device(lu->tgt);
 553         struct sbp2_management_orb *orb;
 554         unsigned int timeout;
 555         int retval = -ENOMEM;
 556
 557         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 558                 return 0;
 559
 560         orb = kzalloc(sizeof(*orb), GFP_NOIO);
 561         if (orb == NULL)
 562                 return -ENOMEM;
 563
 564         kref_init(&orb->base.kref);
 565         orb->response_bus =
 566                 dma_map_single(device->card->device, &orb->response,
 567                                sizeof(orb->response), DMA_FROM_DEVICE);
 568         if (dma_mapping_error(device->card->device, orb->response_bus))
 569                 goto fail_mapping_response;
 570
 571         orb->request.response.high = 0;
 572         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 573
 574         orb->request.misc = cpu_to_be32(
 575                 MANAGEMENT_ORB_NOTIFY |
 576                 MANAGEMENT_ORB_FUNCTION(function) |
 577                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 578         orb->request.length = cpu_to_be32(
 579                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 580
 581         orb->request.status_fifo.high =
 582                 cpu_to_be32(lu->address_handler.offset >> 32);
 583         orb->request.status_fifo.low  =
 584                 cpu_to_be32(lu->address_handler.offset);
 585
 586         if (function == SBP2_LOGIN_REQUEST) {
 587                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 588                 orb->request.misc |= cpu_to_be32(
 589                         MANAGEMENT_ORB_RECONNECT(2) |
 590                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 591                 timeout = lu->tgt->mgt_orb_timeout;
 592         } else {
 593                 timeout = SBP2_ORB_TIMEOUT;
 594         }
 595
 596         init_completion(&orb->done);
 597         orb->base.callback = complete_management_orb;
 598
 599         orb->base.request_bus =
 600                 dma_map_single(device->card->device, &orb->request,
 601                                sizeof(orb->request), DMA_TO_DEVICE);
 602         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 603                 goto fail_mapping_request;
 604
 605         sbp2_send_orb(&orb->base, lu, node_id, generation,
 606                       lu->tgt->management_agent_address);
 607
 608         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 609
 610         retval = -EIO;
 611         if (sbp2_cancel_orbs(lu) == 0) {
 612                 dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
 613                         orb->base.rcode);
 614                 goto out;
 615         }
 616
 617         if (orb->base.rcode != RCODE_COMPLETE) {
 618                 dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
 619                         orb->base.rcode);
 620                 goto out;
 621         }
 622
 623         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 624             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 625                 dev_err(lu_dev(lu), "error status: %d:%d\n",
 626                          STATUS_GET_RESPONSE(orb->status),
 627                          STATUS_GET_SBP_STATUS(orb->status));
 628                 goto out;
 629         }
 630
 631         retval = 0;
 632  out:
 633         dma_unmap_single(device->card->device, orb->base.request_bus,
 634                          sizeof(orb->request), DMA_TO_DEVICE);
 635  fail_mapping_request:
 636         dma_unmap_single(device->card->device, orb->response_bus,
 637                          sizeof(orb->response), DMA_FROM_DEVICE);
 638  fail_mapping_response:
 639         if (response)
 640                 memcpy(response, orb->response, sizeof(orb->response));
 641         kref_put(&orb->base.kref, free_orb);
 642
 643         return retval;
 644 }
 645
 646 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 647 {
 648         struct fw_device *device = target_parent_device(lu->tgt);
 649         __be32 d = 0;
 650
 651         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 652                            lu->tgt->node_id, lu->generation, device->max_speed,
 653                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 654                            &d, 4);
 655 }
 656
 657 static void complete_agent_reset_write_no_wait(struct fw_card *card,
 658                 int rcode, void *payload, size_t length, void *data)
 659 {
 660         kfree(data);
 661 }
 662
 663 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 664 {
 665         struct fw_device *device = target_parent_device(lu->tgt);
 666         struct fw_transaction *t;
 667         static __be32 d;
 668
 669         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 670         if (t == NULL)
 671                 return;
 672
 673         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 674                         lu->tgt->node_id, lu->generation, device->max_speed,
 675                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 676                         &d, 4, complete_agent_reset_write_no_wait, t);
 677 }
 678
 679 static inline void sbp2_allow_block(struct sbp2_target *tgt)
 680 {
 681         spin_lock_irq(&tgt->lock);
 682         --tgt->dont_block;
 683         spin_unlock_irq(&tgt->lock);
 684 }
 685
 686 /*
 687  * Blocks lu->tgt if all of the following conditions are met:
 688  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 689  *     logical units have been finished (indicated by dont_block == 0).
 690  *   - lu->generation is stale.
 691  *
 692  * Note, scsi_block_requests() must be called while holding tgt->lock,
 693  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 694  * unblock the target.
 695  */
 696 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 697 {
 698         struct sbp2_target *tgt = lu->tgt;
 699         struct fw_card *card = target_parent_device(tgt)->card;
 700         struct Scsi_Host *shost =
 701                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 702         unsigned long flags;
 703
 704         spin_lock_irqsave(&tgt->lock, flags);
 705         if (!tgt->dont_block && !lu->blocked &&
 706             lu->generation != card->generation) {
 707                 lu->blocked = true;
 708                 if (++tgt->blocked == 1)
 709                         scsi_block_requests(shost);
 710         }
 711         spin_unlock_irqrestore(&tgt->lock, flags);
 712 }
 713
 714 /*
 715  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 716  * Note, it is harmless to run scsi_unblock_requests() outside the
 717  * tgt->lock protected section.  On the other hand, running it inside
 718  * the section might clash with shost->host_lock.
 719  */
 720 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 721 {
 722         struct sbp2_target *tgt = lu->tgt;
 723         struct fw_card *card = target_parent_device(tgt)->card;
 724         struct Scsi_Host *shost =
 725                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 726         bool unblock = false;
 727
 728         spin_lock_irq(&tgt->lock);
 729         if (lu->blocked && lu->generation == card->generation) {
 730                 lu->blocked = false;
 731                 unblock = --tgt->blocked == 0;
 732         }
 733         spin_unlock_irq(&tgt->lock);
 734
 735         if (unblock)
 736                 scsi_unblock_requests(shost);
 737 }
 738
 739 /*
 740  * Prevents future blocking of tgt and unblocks it.
 741  * Note, it is harmless to run scsi_unblock_requests() outside the
 742  * tgt->lock protected section.  On the other hand, running it inside
 743  * the section might clash with shost->host_lock.
 744  */
 745 static void sbp2_unblock(struct sbp2_target *tgt)
 746 {
 747         struct Scsi_Host *shost =
 748                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 749
 750         spin_lock_irq(&tgt->lock);
 751         ++tgt->dont_block;
 752         spin_unlock_irq(&tgt->lock);
 753
 754         scsi_unblock_requests(shost);
 755 }
 756
 757 static int sbp2_lun2int(u16 lun)
 758 {
 759         struct scsi_lun eight_bytes_lun;
 760
 761         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 762         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 763         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 764
 765         return scsilun_to_int(&eight_bytes_lun);
 766 }
 767
 768 /*
 769  * Write retransmit retry values into the BUSY_TIMEOUT register.
 770  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 771  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 772  *   saner value after logging into the device.
 773  * - The dual-phase retry protocol is optional to implement, and if not
 774  *   supported, writes to the dual-phase portion of the register will be
 775  *   ignored. We try to write the original 1394-1995 default here.
 776  * - In the case of devices that are also SBP-3-compliant, all writes are
 777  *   ignored, as the register is read-only, but contains single-phase retry of
 778  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 779  *   write attempt is safe and yields more consistent behavior for all devices.
 780  *
 781  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 782  * and section 6.4 of the SBP-3 spec for further details.
 783  */
 784 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 785 {
 786         struct fw_device *device = target_parent_device(lu->tgt);
 787         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 788
 789         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 790                            lu->tgt->node_id, lu->generation, device->max_speed,
 791                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
 792 }
 793
 794 static void sbp2_reconnect(struct work_struct *work);
 795
 796 static void sbp2_login(struct work_struct *work)
 797 {
 798         struct sbp2_logical_unit *lu =
 799                 container_of(work, struct sbp2_logical_unit, work.work);
 800         struct sbp2_target *tgt = lu->tgt;
 801         struct fw_device *device = target_parent_device(tgt);
 802         struct Scsi_Host *shost;
 803         struct scsi_device *sdev;
 804         struct sbp2_login_response response;
 805         int generation, node_id, local_node_id;
 806
 807         if (fw_device_is_shutdown(device))
 808                 return;
 809
 810         generation    = device->generation;
 811         smp_rmb();    /* node IDs must not be older than generation */
 812         node_id       = device->node_id;
 813         local_node_id = device->card->node_id;
 814
 815         /* If this is a re-login attempt, log out, or we might be rejected. */
 816         if (lu->has_sdev)
 817                 sbp2_send_management_orb(lu, device->node_id, generation,
 818                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 819
 820         if (sbp2_send_management_orb(lu, node_id, generation,
 821                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 822                 if (lu->retries++ < 5) {
 823                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 824                 } else {
 825                         dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
 826                                 lu->lun);
 827                         /* Let any waiting I/O fail from now on. */
 828                         sbp2_unblock(lu->tgt);
 829                 }
 830                 return;
 831         }
 832
 833         tgt->node_id      = node_id;
 834         tgt->address_high = local_node_id << 16;
 835         smp_wmb();        /* node IDs must not be older than generation */
 836         lu->generation    = generation;
 837
 838         lu->command_block_agent_address =
 839                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 840                       << 32) | be32_to_cpu(response.command_block_agent.low);
 841         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 842
 843         dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
 844                    lu->lun, lu->retries);
 845
 846         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 847         sbp2_set_busy_timeout(lu);
 848
 849         lu->workfn = sbp2_reconnect;
 850         sbp2_agent_reset(lu);
 851
 852         /* This was a re-login. */
 853         if (lu->has_sdev) {
 854                 sbp2_cancel_orbs(lu);
 855                 sbp2_conditionally_unblock(lu);
 856
 857                 return;
 858         }
 859
 860         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 861                 ssleep(SBP2_INQUIRY_DELAY);
 862
 863         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 864         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 865         /*
 866          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 867          * Therefore __scsi_add_device() will get into trouble if a bus reset
 868          * happens in parallel.  It will either fail or leave us with an
 869          * unusable sdev.  As a workaround we check for this and retry the
 870          * whole login and SCSI probing.
 871          */
 872
 873         /* Reported error during __scsi_add_device() */
 874         if (IS_ERR(sdev))
 875                 goto out_logout_login;
 876
 877         /* Unreported error during __scsi_add_device() */
 878         smp_rmb(); /* get current card generation */
 879         if (generation != device->card->generation) {
 880                 scsi_remove_device(sdev);
 881                 scsi_device_put(sdev);
 882                 goto out_logout_login;
 883         }
 884
 885         /* No error during __scsi_add_device() */
 886         lu->has_sdev = true;
 887         scsi_device_put(sdev);
 888         sbp2_allow_block(tgt);
 889
 890         return;
 891
 892  out_logout_login:
 893         smp_rmb(); /* generation may have changed */
 894         generation = device->generation;
 895         smp_rmb(); /* node_id must not be older than generation */
 896
 897         sbp2_send_management_orb(lu, device->node_id, generation,
 898                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 899         /*
 900          * If a bus reset happened, sbp2_update will have requeued
 901          * lu->work already.  Reset the work from reconnect to login.
 902          */
 903         lu->workfn = sbp2_login;
 904 }
 905
 906 static void sbp2_reconnect(struct work_struct *work)
 907 {
 908         struct sbp2_logical_unit *lu =
 909                 container_of(work, struct sbp2_logical_unit, work.work);
 910         struct sbp2_target *tgt = lu->tgt;
 911         struct fw_device *device = target_parent_device(tgt);
 912         int generation, node_id, local_node_id;
 913
 914         if (fw_device_is_shutdown(device))
 915                 return;
 916
 917         generation    = device->generation;
 918         smp_rmb();    /* node IDs must not be older than generation */
 919         node_id       = device->node_id;
 920         local_node_id = device->card->node_id;
 921
 922         if (sbp2_send_management_orb(lu, node_id, generation,
 923                                      SBP2_RECONNECT_REQUEST,
 924                                      lu->login_id, NULL) < 0) {
 925                 /*
 926                  * If reconnect was impossible even though we are in the
 927                  * current generation, fall back and try to log in again.
 928                  *
 929                  * We could check for "Function rejected" status, but
 930                  * looking at the bus generation as simpler and more general.
 931                  */
 932                 smp_rmb(); /* get current card generation */
 933                 if (generation == device->card->generation ||
 934                     lu->retries++ >= 5) {
 935                         dev_err(tgt_dev(tgt), "failed to reconnect\n");
 936                         lu->retries = 0;
 937                         lu->workfn = sbp2_login;
 938                 }
 939                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 940
 941                 return;
 942         }
 943
 944         tgt->node_id      = node_id;
 945         tgt->address_high = local_node_id << 16;
 946         smp_wmb();        /* node IDs must not be older than generation */
 947         lu->generation    = generation;
 948
 949         dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
 950                    lu->lun, lu->retries);
 951
 952         sbp2_agent_reset(lu);
 953         sbp2_cancel_orbs(lu);
 954         sbp2_conditionally_unblock(lu);
 955 }
 956
 957 static void sbp2_lu_workfn(struct work_struct *work)
 958 {
 959         struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
 960                                                 struct sbp2_logical_unit, work);
 961         lu->workfn(work);
 962 }
 963
 964 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 965 {
 966         struct sbp2_logical_unit *lu;
 967
 968         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 969         if (!lu)
 970                 return -ENOMEM;
 971
 972         lu->address_handler.length           = 0x100;
 973         lu->address_handler.address_callback = sbp2_status_write;
 974         lu->address_handler.callback_data    = lu;
 975
 976         if (fw_core_add_address_handler(&lu->address_handler,
 977                                         &fw_high_memory_region) < 0) {
 978                 kfree(lu);
 979                 return -ENOMEM;
 980         }
 981
 982         lu->tgt      = tgt;
 983         lu->lun      = lun_entry & 0xffff;
 984         lu->login_id = INVALID_LOGIN_ID;
 985         lu->retries  = 0;
 986         lu->has_sdev = false;
 987         lu->blocked  = false;
 988         ++tgt->dont_block;
 989         INIT_LIST_HEAD(&lu->orb_list);
 990         lu->workfn = sbp2_login;
 991         INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
 992
 993         list_add_tail(&lu->link, &tgt->lu_list);
 994         return 0;
 995 }
 996
 997 static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
 998                                     const u32 *leaf)
 999 {
1000         if ((leaf[0] & 0xffff0000) == 0x00020000)
1001                 tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1002 }
1003
1004 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1005                                       const u32 *directory)
1006 {
1007         struct fw_csr_iterator ci;
1008         int key, value;
1009
1010         fw_csr_iterator_init(&ci, directory);
1011         while (fw_csr_iterator_next(&ci, &key, &value))
1012                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1013                     sbp2_add_logical_unit(tgt, value) < 0)
1014                         return -ENOMEM;
1015         return 0;
1016 }
1017
1018 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1019                               u32 *model, u32 *firmware_revision)
1020 {
1021         struct fw_csr_iterator ci;
1022         int key, value;
1023
1024         fw_csr_iterator_init(&ci, directory);
1025         while (fw_csr_iterator_next(&ci, &key, &value)) {
1026                 switch (key) {
1027
1028                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1029                         tgt->management_agent_address =
1030                                         CSR_REGISTER_BASE + 4 * value;
1031                         break;
1032
1033                 case CSR_DIRECTORY_ID:
1034                         tgt->directory_id = value;
1035                         break;
1036
1037                 case CSR_MODEL:
1038                         *model = value;
1039                         break;
1040
1041                 case SBP2_CSR_FIRMWARE_REVISION:
1042                         *firmware_revision = value;
1043                         break;
1044
1045                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1046                         /* the timeout value is stored in 500ms units */
1047                         tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1048                         break;
1049
1050                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1051                         if (sbp2_add_logical_unit(tgt, value) < 0)
1052                                 return -ENOMEM;
1053                         break;
1054
1055                 case SBP2_CSR_UNIT_UNIQUE_ID:
1056                         sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1057                         break;
1058
1059                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1060                         /* Adjust for the increment in the iterator */
1061                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1062                                 return -ENOMEM;
1063                         break;
1064                 }
1065         }
1066         return 0;
1067 }
1068
1069 /*
1070  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1071  * provided in the config rom. Most devices do provide a value, which
1072  * we'll use for login management orbs, but with some sane limits.
1073  */
1074 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1075 {
1076         unsigned int timeout = tgt->mgt_orb_timeout;
1077
1078         if (timeout > 40000)
1079                 dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1080                            timeout / 1000);
1081
1082         tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1083 }
1084
1085 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1086                                   u32 firmware_revision)
1087 {
1088         int i;
1089         unsigned int w = sbp2_param_workarounds;
1090
1091         if (w)
1092                 dev_notice(tgt_dev(tgt),
1093                            "Please notify linux1394-devel@lists.sf.net "
1094                            "if you need the workarounds parameter\n");
1095
1096         if (w & SBP2_WORKAROUND_OVERRIDE)
1097                 goto out;
1098
1099         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1100
1101                 if (sbp2_workarounds_table[i].firmware_revision !=
1102                     (firmware_revision & 0xffffff00))
1103                         continue;
1104
1105                 if (sbp2_workarounds_table[i].model != model &&
1106                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1107                         continue;
1108
1109                 w |= sbp2_workarounds_table[i].workarounds;
1110                 break;
1111         }
1112  out:
1113         if (w)
1114                 dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1115                            "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1116                            w, firmware_revision, model);
1117         tgt->workarounds = w;
1118 }
1119
1120 static const struct scsi_host_template scsi_driver_template;
1121 static void sbp2_remove(struct fw_unit *unit);
1122
1123 static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1124 {
1125         struct fw_device *device = fw_parent_device(unit);
1126         struct sbp2_target *tgt;
1127         struct sbp2_logical_unit *lu;
1128         struct Scsi_Host *shost;
1129         u32 model, firmware_revision;
1130
1131         /* cannot (or should not) handle targets on the local node */
1132         if (device->is_local)
1133                 return -ENODEV;
1134
1135         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1136         if (shost == NULL)
1137                 return -ENOMEM;
1138
1139         tgt = (struct sbp2_target *)shost->hostdata;
1140         dev_set_drvdata(&unit->device, tgt);
1141         tgt->unit = unit;
1142         INIT_LIST_HEAD(&tgt->lu_list);
1143         spin_lock_init(&tgt->lock);
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         shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1150
1151         if (scsi_add_host_with_dma(shost, &unit->device,
1152                                    device->card->device) < 0)
1153                 goto fail_shost_put;
1154
1155         /* implicit directory ID */
1156         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1157                              + CSR_CONFIG_ROM) & 0xffffff;
1158
1159         firmware_revision = SBP2_ROM_VALUE_MISSING;
1160         model             = SBP2_ROM_VALUE_MISSING;
1161
1162         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1163                                &firmware_revision) < 0)
1164                 goto fail_remove;
1165
1166         sbp2_clamp_management_orb_timeout(tgt);
1167         sbp2_init_workarounds(tgt, model, firmware_revision);
1168
1169         /*
1170          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1171          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1172          * specifies the max payload size as 2 ^ (max_payload + 2), so
1173          * if we set this to max_speed + 7, we get the right value.
1174          */
1175         tgt->max_payload = min3(device->max_speed + 7, 10U,
1176                                 device->card->max_receive - 1);
1177
1178         /* Do the login in a workqueue so we can easily reschedule retries. */
1179         list_for_each_entry(lu, &tgt->lu_list, link)
1180                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1181
1182         return 0;
1183
1184  fail_remove:
1185         sbp2_remove(unit);
1186         return -ENOMEM;
1187
1188  fail_shost_put:
1189         scsi_host_put(shost);
1190         return -ENOMEM;
1191 }
1192
1193 static void sbp2_update(struct fw_unit *unit)
1194 {
1195         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1196         struct sbp2_logical_unit *lu;
1197
1198         fw_device_enable_phys_dma(fw_parent_device(unit));
1199
1200         /*
1201          * Fw-core serializes sbp2_update() against sbp2_remove().
1202          * Iteration over tgt->lu_list is therefore safe here.
1203          */
1204         list_for_each_entry(lu, &tgt->lu_list, link) {
1205                 sbp2_conditionally_block(lu);
1206                 lu->retries = 0;
1207                 sbp2_queue_work(lu, 0);
1208         }
1209 }
1210
1211 static void sbp2_remove(struct fw_unit *unit)
1212 {
1213         struct fw_device *device = fw_parent_device(unit);
1214         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1215         struct sbp2_logical_unit *lu, *next;
1216         struct Scsi_Host *shost =
1217                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1218         struct scsi_device *sdev;
1219
1220         /* prevent deadlocks */
1221         sbp2_unblock(tgt);
1222
1223         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1224                 cancel_delayed_work_sync(&lu->work);
1225                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1226                 if (sdev) {
1227                         scsi_remove_device(sdev);
1228                         scsi_device_put(sdev);
1229                 }
1230                 if (lu->login_id != INVALID_LOGIN_ID) {
1231                         int generation, node_id;
1232                         /*
1233                          * tgt->node_id may be obsolete here if we failed
1234                          * during initial login or after a bus reset where
1235                          * the topology changed.
1236                          */
1237                         generation = device->generation;
1238                         smp_rmb(); /* node_id vs. generation */
1239                         node_id    = device->node_id;
1240                         sbp2_send_management_orb(lu, node_id, generation,
1241                                                  SBP2_LOGOUT_REQUEST,
1242                                                  lu->login_id, NULL);
1243                 }
1244                 fw_core_remove_address_handler(&lu->address_handler);
1245                 list_del(&lu->link);
1246                 kfree(lu);
1247         }
1248         scsi_remove_host(shost);
1249         dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1250
1251         scsi_host_put(shost);
1252 }
1253
1254 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1255 #define SBP2_SW_VERSION_ENTRY   0x00010483
1256
1257 static const struct ieee1394_device_id sbp2_id_table[] = {
1258         {
1259                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1260                                 IEEE1394_MATCH_VERSION,
1261                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1262                 .version      = SBP2_SW_VERSION_ENTRY,
1263         },
1264         { }
1265 };
1266
1267 static struct fw_driver sbp2_driver = {
1268         .driver   = {
1269                 .owner  = THIS_MODULE,
1270                 .name   = KBUILD_MODNAME,
1271                 .bus    = &fw_bus_type,
1272         },
1273         .probe    = sbp2_probe,
1274         .update   = sbp2_update,
1275         .remove   = sbp2_remove,
1276         .id_table = sbp2_id_table,
1277 };
1278
1279 static void sbp2_unmap_scatterlist(struct device *card_device,
1280                                    struct sbp2_command_orb *orb)
1281 {
1282         scsi_dma_unmap(orb->cmd);
1283
1284         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1285                 dma_unmap_single(card_device, orb->page_table_bus,
1286                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1287 }
1288
1289 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1290 {
1291         int sam_status;
1292         int sfmt = (sbp2_status[0] >> 6) & 0x03;
1293
1294         if (sfmt == 2 || sfmt == 3) {
1295                 /*
1296                  * Reserved for future standardization (2) or
1297                  * Status block format vendor-dependent (3)
1298                  */
1299                 return DID_ERROR << 16;
1300         }
1301
1302         sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1303         sense_data[1] = 0x0;
1304         sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1305         sense_data[3] = sbp2_status[4];
1306         sense_data[4] = sbp2_status[5];
1307         sense_data[5] = sbp2_status[6];
1308         sense_data[6] = sbp2_status[7];
1309         sense_data[7] = 10;
1310         sense_data[8] = sbp2_status[8];
1311         sense_data[9] = sbp2_status[9];
1312         sense_data[10] = sbp2_status[10];
1313         sense_data[11] = sbp2_status[11];
1314         sense_data[12] = sbp2_status[2];
1315         sense_data[13] = sbp2_status[3];
1316         sense_data[14] = sbp2_status[12];
1317         sense_data[15] = sbp2_status[13];
1318
1319         sam_status = sbp2_status[0] & 0x3f;
1320
1321         switch (sam_status) {
1322         case SAM_STAT_GOOD:
1323         case SAM_STAT_CHECK_CONDITION:
1324         case SAM_STAT_CONDITION_MET:
1325         case SAM_STAT_BUSY:
1326         case SAM_STAT_RESERVATION_CONFLICT:
1327         case SAM_STAT_COMMAND_TERMINATED:
1328                 return DID_OK << 16 | sam_status;
1329
1330         default:
1331                 return DID_ERROR << 16;
1332         }
1333 }
1334
1335 static void complete_command_orb(struct sbp2_orb *base_orb,
1336                                  struct sbp2_status *status)
1337 {
1338         struct sbp2_command_orb *orb =
1339                 container_of(base_orb, struct sbp2_command_orb, base);
1340         struct fw_device *device = target_parent_device(base_orb->lu->tgt);
1341         int result;
1342
1343         if (status != NULL) {
1344                 if (STATUS_GET_DEAD(*status))
1345                         sbp2_agent_reset_no_wait(base_orb->lu);
1346
1347                 switch (STATUS_GET_RESPONSE(*status)) {
1348                 case SBP2_STATUS_REQUEST_COMPLETE:
1349                         result = DID_OK << 16;
1350                         break;
1351                 case SBP2_STATUS_TRANSPORT_FAILURE:
1352                         result = DID_BUS_BUSY << 16;
1353                         break;
1354                 case SBP2_STATUS_ILLEGAL_REQUEST:
1355                 case SBP2_STATUS_VENDOR_DEPENDENT:
1356                 default:
1357                         result = DID_ERROR << 16;
1358                         break;
1359                 }
1360
1361                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1362                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1363                                                            orb->cmd->sense_buffer);
1364         } else {
1365                 /*
1366                  * If the orb completes with status == NULL, something
1367                  * went wrong, typically a bus reset happened mid-orb
1368                  * or when sending the write (less likely).
1369                  */
1370                 result = DID_BUS_BUSY << 16;
1371                 sbp2_conditionally_block(base_orb->lu);
1372         }
1373
1374         dma_unmap_single(device->card->device, orb->base.request_bus,
1375                          sizeof(orb->request), DMA_TO_DEVICE);
1376         sbp2_unmap_scatterlist(device->card->device, orb);
1377
1378         orb->cmd->result = result;
1379         scsi_done(orb->cmd);
1380 }
1381
1382 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1383                 struct fw_device *device, struct sbp2_logical_unit *lu)
1384 {
1385         struct scatterlist *sg = scsi_sglist(orb->cmd);
1386         int i, n;
1387
1388         n = scsi_dma_map(orb->cmd);
1389         if (n <= 0)
1390                 goto fail;
1391
1392         /*
1393          * Handle the special case where there is only one element in
1394          * the scatter list by converting it to an immediate block
1395          * request. This is also a workaround for broken devices such
1396          * as the second generation iPod which doesn't support page
1397          * tables.
1398          */
1399         if (n == 1) {
1400                 orb->request.data_descriptor.high =
1401                         cpu_to_be32(lu->tgt->address_high);
1402                 orb->request.data_descriptor.low  =
1403                         cpu_to_be32(sg_dma_address(sg));
1404                 orb->request.misc |=
1405                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1406                 return 0;
1407         }
1408
1409         for_each_sg(sg, sg, n, i) {
1410                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1411                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1412         }
1413
1414         orb->page_table_bus =
1415                 dma_map_single(device->card->device, orb->page_table,
1416                                sizeof(orb->page_table), DMA_TO_DEVICE);
1417         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1418                 goto fail_page_table;
1419
1420         /*
1421          * The data_descriptor pointer is the one case where we need
1422          * to fill in the node ID part of the address.  All other
1423          * pointers assume that the data referenced reside on the
1424          * initiator (i.e. us), but data_descriptor can refer to data
1425          * on other nodes so we need to put our ID in descriptor.high.
1426          */
1427         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1428         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1429         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1430                                          COMMAND_ORB_DATA_SIZE(n));
1431
1432         return 0;
1433
1434  fail_page_table:
1435         scsi_dma_unmap(orb->cmd);
1436  fail:
1437         return -ENOMEM;
1438 }
1439
1440 /* SCSI stack integration */
1441
1442 static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1443                                   struct scsi_cmnd *cmd)
1444 {
1445         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1446         struct fw_device *device = target_parent_device(lu->tgt);
1447         struct sbp2_command_orb *orb;
1448         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1449
1450         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1451         if (orb == NULL)
1452                 return SCSI_MLQUEUE_HOST_BUSY;
1453
1454         /* Initialize rcode to something not RCODE_COMPLETE. */
1455         orb->base.rcode = -1;
1456         kref_init(&orb->base.kref);
1457         orb->cmd = cmd;
1458         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1459         orb->request.misc = cpu_to_be32(
1460                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1461                 COMMAND_ORB_SPEED(device->max_speed) |
1462                 COMMAND_ORB_NOTIFY);
1463
1464         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1465                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1466
1467         generation = device->generation;
1468         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1469
1470         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1471                 goto out;
1472
1473         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1474
1475         orb->base.callback = complete_command_orb;
1476         orb->base.request_bus =
1477                 dma_map_single(device->card->device, &orb->request,
1478                                sizeof(orb->request), DMA_TO_DEVICE);
1479         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1480                 sbp2_unmap_scatterlist(device->card->device, orb);
1481                 goto out;
1482         }
1483
1484         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1485                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1486         retval = 0;
1487  out:
1488         kref_put(&orb->base.kref, free_orb);
1489         return retval;
1490 }
1491
1492 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1493 {
1494         struct sbp2_logical_unit *lu = sdev->hostdata;
1495
1496         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1497         if (!lu)
1498                 return -ENOSYS;
1499
1500         sdev->allow_restart = 1;
1501
1502         /*
1503          * SBP-2 does not require any alignment, but we set it anyway
1504          * for compatibility with earlier versions of this driver.
1505          */
1506         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1507
1508         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1509                 sdev->inquiry_len = 36;
1510
1511         return 0;
1512 }
1513
1514 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1515 {
1516         struct sbp2_logical_unit *lu = sdev->hostdata;
1517
1518         sdev->use_10_for_rw = 1;
1519
1520         if (sbp2_param_exclusive_login)
1521                 sdev->manage_start_stop = 1;
1522
1523         if (sdev->type == TYPE_ROM)
1524                 sdev->use_10_for_ms = 1;
1525
1526         if (sdev->type == TYPE_DISK &&
1527             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1528                 sdev->skip_ms_page_8 = 1;
1529
1530         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1531                 sdev->fix_capacity = 1;
1532
1533         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1534                 sdev->start_stop_pwr_cond = 1;
1535
1536         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1537                 blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1538
1539         return 0;
1540 }
1541
1542 /*
1543  * Called by scsi stack when something has really gone wrong.  Usually
1544  * called when a command has timed-out for some reason.
1545  */
1546 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1547 {
1548         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1549
1550         dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1551         sbp2_agent_reset(lu);
1552         sbp2_cancel_orbs(lu);
1553
1554         return SUCCESS;
1555 }
1556
1557 /*
1558  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1559  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1560  *
1561  * This is the concatenation of target port identifier and logical unit
1562  * identifier as per SAM-2...SAM-4 annex A.
1563  */
1564 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1565                         struct device_attribute *attr, char *buf)
1566 {
1567         struct scsi_device *sdev = to_scsi_device(dev);
1568         struct sbp2_logical_unit *lu;
1569
1570         if (!sdev)
1571                 return 0;
1572
1573         lu = sdev->hostdata;
1574
1575         return sprintf(buf, "%016llx:%06x:%04x\n",
1576                         (unsigned long long)lu->tgt->guid,
1577                         lu->tgt->directory_id, lu->lun);
1578 }
1579
1580 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1581
1582 static struct attribute *sbp2_scsi_sysfs_attrs[] = {
1583         &dev_attr_ieee1394_id.attr,
1584         NULL
1585 };
1586
1587 ATTRIBUTE_GROUPS(sbp2_scsi_sysfs);
1588
1589 static const struct scsi_host_template scsi_driver_template = {
1590         .module                 = THIS_MODULE,
1591         .name                   = "SBP-2 IEEE-1394",
1592         .proc_name              = "sbp2",
1593         .queuecommand           = sbp2_scsi_queuecommand,
1594         .slave_alloc            = sbp2_scsi_slave_alloc,
1595         .slave_configure        = sbp2_scsi_slave_configure,
1596         .eh_abort_handler       = sbp2_scsi_abort,
1597         .this_id                = -1,
1598         .sg_tablesize           = SG_ALL,
1599         .max_segment_size       = SBP2_MAX_SEG_SIZE,
1600         .can_queue              = 1,
1601         .sdev_groups            = sbp2_scsi_sysfs_groups,
1602 };
1603
1604 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1605 MODULE_DESCRIPTION("SCSI over IEEE1394");
1606 MODULE_LICENSE("GPL");
1607 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1608
1609 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1610 MODULE_ALIAS("sbp2");
1611
1612 static int __init sbp2_init(void)
1613 {
1614         return driver_register(&sbp2_driver.driver);
1615 }
1616
1617 static void __exit sbp2_cleanup(void)
1618 {
1619         driver_unregister(&sbp2_driver.driver);
1620 }
1621
1622 module_init(sbp2_init);
1623 module_exit(sbp2_cleanup);