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_system_start_stop or
  85  *   manage_runtime_start_stop is on).
  86  *   Some disks need this to spin down or to resume properly.
  87  *
  88  * - override internal blacklist
  89  *   Instead of adding to the built-in blacklist, use only the workarounds
  90  *   specified in the module load parameter.
  91  *   Useful if a blacklist entry interfered with a non-broken device.
  92  */
  93 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
  94 #define SBP2_WORKAROUND_INQUIRY_36      0x2
  95 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
  96 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
  97 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
  98 #define SBP2_INQUIRY_DELAY              12
  99 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 100 #define SBP2_WORKAROUND_OVERRIDE        0x100
 101
 102 static int sbp2_param_workarounds;
 103 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 104 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 105         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 106         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 107         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 108         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 109         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 110         ", set power condition in start stop unit = "
 111                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 112         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 113         ", or a combination)");
 114
 115 /*
 116  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 117  * and one struct scsi_device per sbp2_logical_unit.
 118  */
 119 struct sbp2_logical_unit {
 120         struct sbp2_target *tgt;
 121         struct list_head link;
 122         struct fw_address_handler address_handler;
 123         struct list_head orb_list;
 124
 125         u64 command_block_agent_address;
 126         u16 lun;
 127         int login_id;
 128
 129         /*
 130          * The generation is updated once we've logged in or reconnected
 131          * to the logical unit.  Thus, I/O to the device will automatically
 132          * fail and get retried if it happens in a window where the device
 133          * is not ready, e.g. after a bus reset but before we reconnect.
 134          */
 135         int generation;
 136         int retries;
 137         work_func_t workfn;
 138         struct delayed_work work;
 139         bool has_sdev;
 140         bool blocked;
 141 };
 142
 143 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 144 {
 145         queue_delayed_work(fw_workqueue, &lu->work, delay);
 146 }
 147
 148 /*
 149  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 150  * and one struct Scsi_Host per sbp2_target.
 151  */
 152 struct sbp2_target {
 153         struct fw_unit *unit;
 154         struct list_head lu_list;
 155
 156         u64 management_agent_address;
 157         u64 guid;
 158         int directory_id;
 159         int node_id;
 160         int address_high;
 161         unsigned int workarounds;
 162         unsigned int mgt_orb_timeout;
 163         unsigned int max_payload;
 164
 165         spinlock_t lock;
 166         int dont_block; /* counter for each logical unit */
 167         int blocked;    /* ditto */
 168 };
 169
 170 static struct fw_device *target_parent_device(struct sbp2_target *tgt)
 171 {
 172         return fw_parent_device(tgt->unit);
 173 }
 174
 175 static const struct device *tgt_dev(const struct sbp2_target *tgt)
 176 {
 177         return &tgt->unit->device;
 178 }
 179
 180 static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
 181 {
 182         return &lu->tgt->unit->device;
 183 }
 184
 185 /* Impossible login_id, to detect logout attempt before successful login */
 186 #define INVALID_LOGIN_ID 0x10000
 187
 188 #define SBP2_ORB_TIMEOUT                2000U           /* Timeout in ms */
 189 #define SBP2_ORB_NULL                   0x80000000
 190 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 191 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 192
 193 /*
 194  * There is no transport protocol limit to the CDB length,  but we implement
 195  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
 196  */
 197 #define SBP2_MAX_CDB_SIZE               16
 198
 199 /*
 200  * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
 201  * for compatibility with earlier versions of this driver.
 202  */
 203 #define SBP2_MAX_SEG_SIZE               0xfffc
 204
 205 /* Unit directory keys */
 206 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 207 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 208 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 209 #define SBP2_CSR_UNIT_UNIQUE_ID         0x8d
 210 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 211
 212 /* Management orb opcodes */
 213 #define SBP2_LOGIN_REQUEST              0x0
 214 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 215 #define SBP2_RECONNECT_REQUEST          0x3
 216 #define SBP2_SET_PASSWORD_REQUEST       0x4
 217 #define SBP2_LOGOUT_REQUEST             0x7
 218 #define SBP2_ABORT_TASK_REQUEST         0xb
 219 #define SBP2_ABORT_TASK_SET             0xc
 220 #define SBP2_LOGICAL_UNIT_RESET         0xe
 221 #define SBP2_TARGET_RESET_REQUEST       0xf
 222
 223 /* Offsets for command block agent registers */
 224 #define SBP2_AGENT_STATE                0x00
 225 #define SBP2_AGENT_RESET                0x04
 226 #define SBP2_ORB_POINTER                0x08
 227 #define SBP2_DOORBELL                   0x10
 228 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 229
 230 /* Status write response codes */
 231 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 232 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 233 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 234 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 235
 236 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 237 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 238 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 239 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 240 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 241 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 242 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 243 #define STATUS_GET_DATA(v)              ((v).data)
 244
 245 struct sbp2_status {
 246         u32 status;
 247         u32 orb_low;
 248         u8 data[24];
 249 };
 250
 251 struct sbp2_pointer {
 252         __be32 high;
 253         __be32 low;
 254 };
 255
 256 struct sbp2_orb {
 257         struct fw_transaction t;
 258         struct kref kref;
 259         dma_addr_t request_bus;
 260         int rcode;
 261         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 262         struct sbp2_logical_unit *lu;
 263         struct list_head link;
 264 };
 265
 266 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 267 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 268 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 269 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 270 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 271 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 272
 273 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 274 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 275
 276 struct sbp2_management_orb {
 277         struct sbp2_orb base;
 278         struct {
 279                 struct sbp2_pointer password;
 280                 struct sbp2_pointer response;
 281                 __be32 misc;
 282                 __be32 length;
 283                 struct sbp2_pointer status_fifo;
 284         } request;
 285         __be32 response[4];
 286         dma_addr_t response_bus;
 287         struct completion done;
 288         struct sbp2_status status;
 289 };
 290
 291 struct sbp2_login_response {
 292         __be32 misc;
 293         struct sbp2_pointer command_block_agent;
 294         __be32 reconnect_hold;
 295 };
 296 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 297 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 298 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 299 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 300 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 301 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 302 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 303 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 304
 305 struct sbp2_command_orb {
 306         struct sbp2_orb base;
 307         struct {
 308                 struct sbp2_pointer next;
 309                 struct sbp2_pointer data_descriptor;
 310                 __be32 misc;
 311                 u8 command_block[SBP2_MAX_CDB_SIZE];
 312         } request;
 313         struct scsi_cmnd *cmd;
 314
 315         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 316         dma_addr_t page_table_bus;
 317 };
 318
 319 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 320 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 321
 322 /*
 323  * List of devices with known bugs.
 324  *
 325  * The firmware_revision field, masked with 0xffff00, is the best
 326  * indicator for the type of bridge chip of a device.  It yields a few
 327  * false positives but this did not break correctly behaving devices
 328  * so far.
 329  */
 330 static const struct {
 331         u32 firmware_revision;
 332         u32 model;
 333         unsigned int workarounds;
 334 } sbp2_workarounds_table[] = {
 335         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 336                 .firmware_revision      = 0x002800,
 337                 .model                  = 0x001010,
 338                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 339                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 340                                           SBP2_WORKAROUND_POWER_CONDITION,
 341         },
 342         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 343                 .firmware_revision      = 0x002800,
 344                 .model                  = 0x000000,
 345                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 346         },
 347         /* Initio bridges, actually only needed for some older ones */ {
 348                 .firmware_revision      = 0x000200,
 349                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 350                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 351         },
 352         /* PL-3507 bridge with Prolific firmware */ {
 353                 .firmware_revision      = 0x012800,
 354                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 355                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 356         },
 357         /* Symbios bridge */ {
 358                 .firmware_revision      = 0xa0b800,
 359                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 360                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 361         },
 362         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 363                 .firmware_revision      = 0x002600,
 364                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 365                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 366         },
 367         /*
 368          * iPod 2nd generation: needs 128k max transfer size workaround
 369          * iPod 3rd generation: needs fix capacity workaround
 370          */
 371         {
 372                 .firmware_revision      = 0x0a2700,
 373                 .model                  = 0x000000,
 374                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 375                                           SBP2_WORKAROUND_FIX_CAPACITY,
 376         },
 377         /* iPod 4th generation */ {
 378                 .firmware_revision      = 0x0a2700,
 379                 .model                  = 0x000021,
 380                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 381         },
 382         /* iPod mini */ {
 383                 .firmware_revision      = 0x0a2700,
 384                 .model                  = 0x000022,
 385                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 386         },
 387         /* iPod mini */ {
 388                 .firmware_revision      = 0x0a2700,
 389                 .model                  = 0x000023,
 390                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 391         },
 392         /* iPod Photo */ {
 393                 .firmware_revision      = 0x0a2700,
 394                 .model                  = 0x00007e,
 395                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 396         }
 397 };
 398
 399 static void free_orb(struct kref *kref)
 400 {
 401         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 402
 403         kfree(orb);
 404 }
 405
 406 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 407                               int tcode, int destination, int source,
 408                               int generation, unsigned long long offset,
 409                               void *payload, size_t length, void *callback_data)
 410 {
 411         struct sbp2_logical_unit *lu = callback_data;
 412         struct sbp2_orb *orb = NULL, *iter;
 413         struct sbp2_status status;
 414         unsigned long flags;
 415
 416         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 417             length < 8 || length > sizeof(status)) {
 418                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 419                 return;
 420         }
 421
 422         status.status  = be32_to_cpup(payload);
 423         status.orb_low = be32_to_cpup(payload + 4);
 424         memset(status.data, 0, sizeof(status.data));
 425         if (length > 8)
 426                 memcpy(status.data, payload + 8, length - 8);
 427
 428         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 429                 dev_notice(lu_dev(lu),
 430                            "non-ORB related status write, not handled\n");
 431                 fw_send_response(card, request, RCODE_COMPLETE);
 432                 return;
 433         }
 434
 435         /* Lookup the orb corresponding to this status write. */
 436         spin_lock_irqsave(&lu->tgt->lock, flags);
 437         list_for_each_entry(iter, &lu->orb_list, link) {
 438                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 439                     STATUS_GET_ORB_LOW(status) == iter->request_bus) {
 440                         iter->rcode = RCODE_COMPLETE;
 441                         list_del(&iter->link);
 442                         orb = iter;
 443                         break;
 444                 }
 445         }
 446         spin_unlock_irqrestore(&lu->tgt->lock, flags);
 447
 448         if (orb) {
 449                 orb->callback(orb, &status);
 450                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 451         } else {
 452                 dev_err(lu_dev(lu), "status write for unknown ORB\n");
 453         }
 454
 455         fw_send_response(card, request, RCODE_COMPLETE);
 456 }
 457
 458 static void complete_transaction(struct fw_card *card, int rcode,
 459                                  void *payload, size_t length, void *data)
 460 {
 461         struct sbp2_orb *orb = data;
 462         unsigned long flags;
 463
 464         /*
 465          * This is a little tricky.  We can get the status write for
 466          * the orb before we get this callback.  The status write
 467          * handler above will assume the orb pointer transaction was
 468          * successful and set the rcode to RCODE_COMPLETE for the orb.
 469          * So this callback only sets the rcode if it hasn't already
 470          * been set and only does the cleanup if the transaction
 471          * failed and we didn't already get a status write.
 472          */
 473         spin_lock_irqsave(&orb->lu->tgt->lock, flags);
 474
 475         if (orb->rcode == -1)
 476                 orb->rcode = rcode;
 477         if (orb->rcode != RCODE_COMPLETE) {
 478                 list_del(&orb->link);
 479                 spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 480
 481                 orb->callback(orb, NULL);
 482                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 483         } else {
 484                 spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 485         }
 486
 487         kref_put(&orb->kref, free_orb); /* transaction callback reference */
 488 }
 489
 490 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 491                           int node_id, int generation, u64 offset)
 492 {
 493         struct fw_device *device = target_parent_device(lu->tgt);
 494         struct sbp2_pointer orb_pointer;
 495         unsigned long flags;
 496
 497         orb_pointer.high = 0;
 498         orb_pointer.low = cpu_to_be32(orb->request_bus);
 499
 500         orb->lu = lu;
 501         spin_lock_irqsave(&lu->tgt->lock, flags);
 502         list_add_tail(&orb->link, &lu->orb_list);
 503         spin_unlock_irqrestore(&lu->tgt->lock, flags);
 504
 505         kref_get(&orb->kref); /* transaction callback reference */
 506         kref_get(&orb->kref); /* orb callback reference */
 507
 508         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 509                         node_id, generation, device->max_speed, offset,
 510                         &orb_pointer, 8, complete_transaction, orb);
 511 }
 512
 513 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 514 {
 515         struct fw_device *device = target_parent_device(lu->tgt);
 516         struct sbp2_orb *orb, *next;
 517         struct list_head list;
 518         int retval = -ENOENT;
 519
 520         INIT_LIST_HEAD(&list);
 521         spin_lock_irq(&lu->tgt->lock);
 522         list_splice_init(&lu->orb_list, &list);
 523         spin_unlock_irq(&lu->tgt->lock);
 524
 525         list_for_each_entry_safe(orb, next, &list, link) {
 526                 retval = 0;
 527                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 528                         continue;
 529
 530                 orb->rcode = RCODE_CANCELLED;
 531                 orb->callback(orb, NULL);
 532                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 533         }
 534
 535         return retval;
 536 }
 537
 538 static void complete_management_orb(struct sbp2_orb *base_orb,
 539                                     struct sbp2_status *status)
 540 {
 541         struct sbp2_management_orb *orb =
 542                 container_of(base_orb, struct sbp2_management_orb, base);
 543
 544         if (status)
 545                 memcpy(&orb->status, status, sizeof(*status));
 546         complete(&orb->done);
 547 }
 548
 549 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 550                                     int generation, int function,
 551                                     int lun_or_login_id, void *response)
 552 {
 553         struct fw_device *device = target_parent_device(lu->tgt);
 554         struct sbp2_management_orb *orb;
 555         unsigned int timeout;
 556         int retval = -ENOMEM;
 557
 558         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 559                 return 0;
 560
 561         orb = kzalloc(sizeof(*orb), GFP_NOIO);
 562         if (orb == NULL)
 563                 return -ENOMEM;
 564
 565         kref_init(&orb->base.kref);
 566         orb->response_bus =
 567                 dma_map_single(device->card->device, &orb->response,
 568                                sizeof(orb->response), DMA_FROM_DEVICE);
 569         if (dma_mapping_error(device->card->device, orb->response_bus))
 570                 goto fail_mapping_response;
 571
 572         orb->request.response.high = 0;
 573         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 574
 575         orb->request.misc = cpu_to_be32(
 576                 MANAGEMENT_ORB_NOTIFY |
 577                 MANAGEMENT_ORB_FUNCTION(function) |
 578                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 579         orb->request.length = cpu_to_be32(
 580                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 581
 582         orb->request.status_fifo.high =
 583                 cpu_to_be32(lu->address_handler.offset >> 32);
 584         orb->request.status_fifo.low  =
 585                 cpu_to_be32(lu->address_handler.offset);
 586
 587         if (function == SBP2_LOGIN_REQUEST) {
 588                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 589                 orb->request.misc |= cpu_to_be32(
 590                         MANAGEMENT_ORB_RECONNECT(2) |
 591                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 592                 timeout = lu->tgt->mgt_orb_timeout;
 593         } else {
 594                 timeout = SBP2_ORB_TIMEOUT;
 595         }
 596
 597         init_completion(&orb->done);
 598         orb->base.callback = complete_management_orb;
 599
 600         orb->base.request_bus =
 601                 dma_map_single(device->card->device, &orb->request,
 602                                sizeof(orb->request), DMA_TO_DEVICE);
 603         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 604                 goto fail_mapping_request;
 605
 606         sbp2_send_orb(&orb->base, lu, node_id, generation,
 607                       lu->tgt->management_agent_address);
 608
 609         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 610
 611         retval = -EIO;
 612         if (sbp2_cancel_orbs(lu) == 0) {
 613                 dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
 614                         orb->base.rcode);
 615                 goto out;
 616         }
 617
 618         if (orb->base.rcode != RCODE_COMPLETE) {
 619                 dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
 620                         orb->base.rcode);
 621                 goto out;
 622         }
 623
 624         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 625             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 626                 dev_err(lu_dev(lu), "error status: %d:%d\n",
 627                          STATUS_GET_RESPONSE(orb->status),
 628                          STATUS_GET_SBP_STATUS(orb->status));
 629                 goto out;
 630         }
 631
 632         retval = 0;
 633  out:
 634         dma_unmap_single(device->card->device, orb->base.request_bus,
 635                          sizeof(orb->request), DMA_TO_DEVICE);
 636  fail_mapping_request:
 637         dma_unmap_single(device->card->device, orb->response_bus,
 638                          sizeof(orb->response), DMA_FROM_DEVICE);
 639  fail_mapping_response:
 640         if (response)
 641                 memcpy(response, orb->response, sizeof(orb->response));
 642         kref_put(&orb->base.kref, free_orb);
 643
 644         return retval;
 645 }
 646
 647 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 648 {
 649         struct fw_device *device = target_parent_device(lu->tgt);
 650         __be32 d = 0;
 651
 652         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 653                            lu->tgt->node_id, lu->generation, device->max_speed,
 654                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 655                            &d, 4);
 656 }
 657
 658 static void complete_agent_reset_write_no_wait(struct fw_card *card,
 659                 int rcode, void *payload, size_t length, void *data)
 660 {
 661         kfree(data);
 662 }
 663
 664 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 665 {
 666         struct fw_device *device = target_parent_device(lu->tgt);
 667         struct fw_transaction *t;
 668         static __be32 d;
 669
 670         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 671         if (t == NULL)
 672                 return;
 673
 674         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 675                         lu->tgt->node_id, lu->generation, device->max_speed,
 676                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 677                         &d, 4, complete_agent_reset_write_no_wait, t);
 678 }
 679
 680 static inline void sbp2_allow_block(struct sbp2_target *tgt)
 681 {
 682         spin_lock_irq(&tgt->lock);
 683         --tgt->dont_block;
 684         spin_unlock_irq(&tgt->lock);
 685 }
 686
 687 /*
 688  * Blocks lu->tgt if all of the following conditions are met:
 689  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 690  *     logical units have been finished (indicated by dont_block == 0).
 691  *   - lu->generation is stale.
 692  *
 693  * Note, scsi_block_requests() must be called while holding tgt->lock,
 694  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 695  * unblock the target.
 696  */
 697 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 698 {
 699         struct sbp2_target *tgt = lu->tgt;
 700         struct fw_card *card = target_parent_device(tgt)->card;
 701         struct Scsi_Host *shost =
 702                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 703         unsigned long flags;
 704
 705         spin_lock_irqsave(&tgt->lock, flags);
 706         if (!tgt->dont_block && !lu->blocked &&
 707             lu->generation != card->generation) {
 708                 lu->blocked = true;
 709                 if (++tgt->blocked == 1)
 710                         scsi_block_requests(shost);
 711         }
 712         spin_unlock_irqrestore(&tgt->lock, flags);
 713 }
 714
 715 /*
 716  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 717  * Note, it is harmless to run scsi_unblock_requests() outside the
 718  * tgt->lock protected section.  On the other hand, running it inside
 719  * the section might clash with shost->host_lock.
 720  */
 721 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 722 {
 723         struct sbp2_target *tgt = lu->tgt;
 724         struct fw_card *card = target_parent_device(tgt)->card;
 725         struct Scsi_Host *shost =
 726                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 727         bool unblock = false;
 728
 729         spin_lock_irq(&tgt->lock);
 730         if (lu->blocked && lu->generation == card->generation) {
 731                 lu->blocked = false;
 732                 unblock = --tgt->blocked == 0;
 733         }
 734         spin_unlock_irq(&tgt->lock);
 735
 736         if (unblock)
 737                 scsi_unblock_requests(shost);
 738 }
 739
 740 /*
 741  * Prevents future blocking of tgt and unblocks it.
 742  * Note, it is harmless to run scsi_unblock_requests() outside the
 743  * tgt->lock protected section.  On the other hand, running it inside
 744  * the section might clash with shost->host_lock.
 745  */
 746 static void sbp2_unblock(struct sbp2_target *tgt)
 747 {
 748         struct Scsi_Host *shost =
 749                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 750
 751         spin_lock_irq(&tgt->lock);
 752         ++tgt->dont_block;
 753         spin_unlock_irq(&tgt->lock);
 754
 755         scsi_unblock_requests(shost);
 756 }
 757
 758 static int sbp2_lun2int(u16 lun)
 759 {
 760         struct scsi_lun eight_bytes_lun;
 761
 762         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 763         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 764         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 765
 766         return scsilun_to_int(&eight_bytes_lun);
 767 }
 768
 769 /*
 770  * Write retransmit retry values into the BUSY_TIMEOUT register.
 771  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 772  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 773  *   saner value after logging into the device.
 774  * - The dual-phase retry protocol is optional to implement, and if not
 775  *   supported, writes to the dual-phase portion of the register will be
 776  *   ignored. We try to write the original 1394-1995 default here.
 777  * - In the case of devices that are also SBP-3-compliant, all writes are
 778  *   ignored, as the register is read-only, but contains single-phase retry of
 779  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 780  *   write attempt is safe and yields more consistent behavior for all devices.
 781  *
 782  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 783  * and section 6.4 of the SBP-3 spec for further details.
 784  */
 785 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 786 {
 787         struct fw_device *device = target_parent_device(lu->tgt);
 788         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 789
 790         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 791                            lu->tgt->node_id, lu->generation, device->max_speed,
 792                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
 793 }
 794
 795 static void sbp2_reconnect(struct work_struct *work);
 796
 797 static void sbp2_login(struct work_struct *work)
 798 {
 799         struct sbp2_logical_unit *lu =
 800                 container_of(work, struct sbp2_logical_unit, work.work);
 801         struct sbp2_target *tgt = lu->tgt;
 802         struct fw_device *device = target_parent_device(tgt);
 803         struct Scsi_Host *shost;
 804         struct scsi_device *sdev;
 805         struct sbp2_login_response response;
 806         int generation, node_id, local_node_id;
 807
 808         if (fw_device_is_shutdown(device))
 809                 return;
 810
 811         generation    = device->generation;
 812         smp_rmb();    /* node IDs must not be older than generation */
 813         node_id       = device->node_id;
 814         local_node_id = device->card->node_id;
 815
 816         /* If this is a re-login attempt, log out, or we might be rejected. */
 817         if (lu->has_sdev)
 818                 sbp2_send_management_orb(lu, device->node_id, generation,
 819                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 820
 821         if (sbp2_send_management_orb(lu, node_id, generation,
 822                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 823                 if (lu->retries++ < 5) {
 824                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 825                 } else {
 826                         dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
 827                                 lu->lun);
 828                         /* Let any waiting I/O fail from now on. */
 829                         sbp2_unblock(lu->tgt);
 830                 }
 831                 return;
 832         }
 833
 834         tgt->node_id      = node_id;
 835         tgt->address_high = local_node_id << 16;
 836         smp_wmb();        /* node IDs must not be older than generation */
 837         lu->generation    = generation;
 838
 839         lu->command_block_agent_address =
 840                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 841                       << 32) | be32_to_cpu(response.command_block_agent.low);
 842         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 843
 844         dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
 845                    lu->lun, lu->retries);
 846
 847         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 848         sbp2_set_busy_timeout(lu);
 849
 850         lu->workfn = sbp2_reconnect;
 851         sbp2_agent_reset(lu);
 852
 853         /* This was a re-login. */
 854         if (lu->has_sdev) {
 855                 sbp2_cancel_orbs(lu);
 856                 sbp2_conditionally_unblock(lu);
 857
 858                 return;
 859         }
 860
 861         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 862                 ssleep(SBP2_INQUIRY_DELAY);
 863
 864         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 865         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 866         /*
 867          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 868          * Therefore __scsi_add_device() will get into trouble if a bus reset
 869          * happens in parallel.  It will either fail or leave us with an
 870          * unusable sdev.  As a workaround we check for this and retry the
 871          * whole login and SCSI probing.
 872          */
 873
 874         /* Reported error during __scsi_add_device() */
 875         if (IS_ERR(sdev))
 876                 goto out_logout_login;
 877
 878         /* Unreported error during __scsi_add_device() */
 879         smp_rmb(); /* get current card generation */
 880         if (generation != device->card->generation) {
 881                 scsi_remove_device(sdev);
 882                 scsi_device_put(sdev);
 883                 goto out_logout_login;
 884         }
 885
 886         /* No error during __scsi_add_device() */
 887         lu->has_sdev = true;
 888         scsi_device_put(sdev);
 889         sbp2_allow_block(tgt);
 890
 891         return;
 892
 893  out_logout_login:
 894         smp_rmb(); /* generation may have changed */
 895         generation = device->generation;
 896         smp_rmb(); /* node_id must not be older than generation */
 897
 898         sbp2_send_management_orb(lu, device->node_id, generation,
 899                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 900         /*
 901          * If a bus reset happened, sbp2_update will have requeued
 902          * lu->work already.  Reset the work from reconnect to login.
 903          */
 904         lu->workfn = sbp2_login;
 905 }
 906
 907 static void sbp2_reconnect(struct work_struct *work)
 908 {
 909         struct sbp2_logical_unit *lu =
 910                 container_of(work, struct sbp2_logical_unit, work.work);
 911         struct sbp2_target *tgt = lu->tgt;
 912         struct fw_device *device = target_parent_device(tgt);
 913         int generation, node_id, local_node_id;
 914
 915         if (fw_device_is_shutdown(device))
 916                 return;
 917
 918         generation    = device->generation;
 919         smp_rmb();    /* node IDs must not be older than generation */
 920         node_id       = device->node_id;
 921         local_node_id = device->card->node_id;
 922
 923         if (sbp2_send_management_orb(lu, node_id, generation,
 924                                      SBP2_RECONNECT_REQUEST,
 925                                      lu->login_id, NULL) < 0) {
 926                 /*
 927                  * If reconnect was impossible even though we are in the
 928                  * current generation, fall back and try to log in again.
 929                  *
 930                  * We could check for "Function rejected" status, but
 931                  * looking at the bus generation as simpler and more general.
 932                  */
 933                 smp_rmb(); /* get current card generation */
 934                 if (generation == device->card->generation ||
 935                     lu->retries++ >= 5) {
 936                         dev_err(tgt_dev(tgt), "failed to reconnect\n");
 937                         lu->retries = 0;
 938                         lu->workfn = sbp2_login;
 939                 }
 940                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 941
 942                 return;
 943         }
 944
 945         tgt->node_id      = node_id;
 946         tgt->address_high = local_node_id << 16;
 947         smp_wmb();        /* node IDs must not be older than generation */
 948         lu->generation    = generation;
 949
 950         dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
 951                    lu->lun, lu->retries);
 952
 953         sbp2_agent_reset(lu);
 954         sbp2_cancel_orbs(lu);
 955         sbp2_conditionally_unblock(lu);
 956 }
 957
 958 static void sbp2_lu_workfn(struct work_struct *work)
 959 {
 960         struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
 961                                                 struct sbp2_logical_unit, work);
 962         lu->workfn(work);
 963 }
 964
 965 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 966 {
 967         struct sbp2_logical_unit *lu;
 968
 969         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 970         if (!lu)
 971                 return -ENOMEM;
 972
 973         lu->address_handler.length           = 0x100;
 974         lu->address_handler.address_callback = sbp2_status_write;
 975         lu->address_handler.callback_data    = lu;
 976
 977         if (fw_core_add_address_handler(&lu->address_handler,
 978                                         &fw_high_memory_region) < 0) {
 979                 kfree(lu);
 980                 return -ENOMEM;
 981         }
 982
 983         lu->tgt      = tgt;
 984         lu->lun      = lun_entry & 0xffff;
 985         lu->login_id = INVALID_LOGIN_ID;
 986         lu->retries  = 0;
 987         lu->has_sdev = false;
 988         lu->blocked  = false;
 989         ++tgt->dont_block;
 990         INIT_LIST_HEAD(&lu->orb_list);
 991         lu->workfn = sbp2_login;
 992         INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
 993
 994         list_add_tail(&lu->link, &tgt->lu_list);
 995         return 0;
 996 }
 997
 998 static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
 999                                     const u32 *leaf)
1000 {
1001         if ((leaf[0] & 0xffff0000) == 0x00020000)
1002                 tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1003 }
1004
1005 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1006                                       const u32 *directory)
1007 {
1008         struct fw_csr_iterator ci;
1009         int key, value;
1010
1011         fw_csr_iterator_init(&ci, directory);
1012         while (fw_csr_iterator_next(&ci, &key, &value))
1013                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1014                     sbp2_add_logical_unit(tgt, value) < 0)
1015                         return -ENOMEM;
1016         return 0;
1017 }
1018
1019 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1020                               u32 *model, u32 *firmware_revision)
1021 {
1022         struct fw_csr_iterator ci;
1023         int key, value;
1024
1025         fw_csr_iterator_init(&ci, directory);
1026         while (fw_csr_iterator_next(&ci, &key, &value)) {
1027                 switch (key) {
1028
1029                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1030                         tgt->management_agent_address =
1031                                         CSR_REGISTER_BASE + 4 * value;
1032                         break;
1033
1034                 case CSR_DIRECTORY_ID:
1035                         tgt->directory_id = value;
1036                         break;
1037
1038                 case CSR_MODEL:
1039                         *model = value;
1040                         break;
1041
1042                 case SBP2_CSR_FIRMWARE_REVISION:
1043                         *firmware_revision = value;
1044                         break;
1045
1046                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1047                         /* the timeout value is stored in 500ms units */
1048                         tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1049                         break;
1050
1051                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1052                         if (sbp2_add_logical_unit(tgt, value) < 0)
1053                                 return -ENOMEM;
1054                         break;
1055
1056                 case SBP2_CSR_UNIT_UNIQUE_ID:
1057                         sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1058                         break;
1059
1060                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1061                         /* Adjust for the increment in the iterator */
1062                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1063                                 return -ENOMEM;
1064                         break;
1065                 }
1066         }
1067         return 0;
1068 }
1069
1070 /*
1071  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1072  * provided in the config rom. Most devices do provide a value, which
1073  * we'll use for login management orbs, but with some sane limits.
1074  */
1075 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1076 {
1077         unsigned int timeout = tgt->mgt_orb_timeout;
1078
1079         if (timeout > 40000)
1080                 dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1081                            timeout / 1000);
1082
1083         tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1084 }
1085
1086 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1087                                   u32 firmware_revision)
1088 {
1089         int i;
1090         unsigned int w = sbp2_param_workarounds;
1091
1092         if (w)
1093                 dev_notice(tgt_dev(tgt),
1094                            "Please notify linux1394-devel@lists.sf.net "
1095                            "if you need the workarounds parameter\n");
1096
1097         if (w & SBP2_WORKAROUND_OVERRIDE)
1098                 goto out;
1099
1100         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1101
1102                 if (sbp2_workarounds_table[i].firmware_revision !=
1103                     (firmware_revision & 0xffffff00))
1104                         continue;
1105
1106                 if (sbp2_workarounds_table[i].model != model &&
1107                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1108                         continue;
1109
1110                 w |= sbp2_workarounds_table[i].workarounds;
1111                 break;
1112         }
1113  out:
1114         if (w)
1115                 dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1116                            "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1117                            w, firmware_revision, model);
1118         tgt->workarounds = w;
1119 }
1120
1121 static const struct scsi_host_template scsi_driver_template;
1122 static void sbp2_remove(struct fw_unit *unit);
1123
1124 static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1125 {
1126         struct fw_device *device = fw_parent_device(unit);
1127         struct sbp2_target *tgt;
1128         struct sbp2_logical_unit *lu;
1129         struct Scsi_Host *shost;
1130         u32 model, firmware_revision;
1131
1132         /* cannot (or should not) handle targets on the local node */
1133         if (device->is_local)
1134                 return -ENODEV;
1135
1136         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1137         if (shost == NULL)
1138                 return -ENOMEM;
1139
1140         tgt = (struct sbp2_target *)shost->hostdata;
1141         dev_set_drvdata(&unit->device, tgt);
1142         tgt->unit = unit;
1143         INIT_LIST_HEAD(&tgt->lu_list);
1144         spin_lock_init(&tgt->lock);
1145         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1146
1147         if (fw_device_enable_phys_dma(device) < 0)
1148                 goto fail_shost_put;
1149
1150         shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1151
1152         if (scsi_add_host_with_dma(shost, &unit->device,
1153                                    device->card->device) < 0)
1154                 goto fail_shost_put;
1155
1156         /* implicit directory ID */
1157         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1158                              + CSR_CONFIG_ROM) & 0xffffff;
1159
1160         firmware_revision = SBP2_ROM_VALUE_MISSING;
1161         model             = SBP2_ROM_VALUE_MISSING;
1162
1163         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1164                                &firmware_revision) < 0)
1165                 goto fail_remove;
1166
1167         sbp2_clamp_management_orb_timeout(tgt);
1168         sbp2_init_workarounds(tgt, model, firmware_revision);
1169
1170         /*
1171          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1172          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1173          * specifies the max payload size as 2 ^ (max_payload + 2), so
1174          * if we set this to max_speed + 7, we get the right value.
1175          */
1176         tgt->max_payload = min3(device->max_speed + 7, 10U,
1177                                 device->card->max_receive - 1);
1178
1179         /* Do the login in a workqueue so we can easily reschedule retries. */
1180         list_for_each_entry(lu, &tgt->lu_list, link)
1181                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1182
1183         return 0;
1184
1185  fail_remove:
1186         sbp2_remove(unit);
1187         return -ENOMEM;
1188
1189  fail_shost_put:
1190         scsi_host_put(shost);
1191         return -ENOMEM;
1192 }
1193
1194 static void sbp2_update(struct fw_unit *unit)
1195 {
1196         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1197         struct sbp2_logical_unit *lu;
1198
1199         fw_device_enable_phys_dma(fw_parent_device(unit));
1200
1201         /*
1202          * Fw-core serializes sbp2_update() against sbp2_remove().
1203          * Iteration over tgt->lu_list is therefore safe here.
1204          */
1205         list_for_each_entry(lu, &tgt->lu_list, link) {
1206                 sbp2_conditionally_block(lu);
1207                 lu->retries = 0;
1208                 sbp2_queue_work(lu, 0);
1209         }
1210 }
1211
1212 static void sbp2_remove(struct fw_unit *unit)
1213 {
1214         struct fw_device *device = fw_parent_device(unit);
1215         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1216         struct sbp2_logical_unit *lu, *next;
1217         struct Scsi_Host *shost =
1218                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1219         struct scsi_device *sdev;
1220
1221         /* prevent deadlocks */
1222         sbp2_unblock(tgt);
1223
1224         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1225                 cancel_delayed_work_sync(&lu->work);
1226                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1227                 if (sdev) {
1228                         scsi_remove_device(sdev);
1229                         scsi_device_put(sdev);
1230                 }
1231                 if (lu->login_id != INVALID_LOGIN_ID) {
1232                         int generation, node_id;
1233                         /*
1234                          * tgt->node_id may be obsolete here if we failed
1235                          * during initial login or after a bus reset where
1236                          * the topology changed.
1237                          */
1238                         generation = device->generation;
1239                         smp_rmb(); /* node_id vs. generation */
1240                         node_id    = device->node_id;
1241                         sbp2_send_management_orb(lu, node_id, generation,
1242                                                  SBP2_LOGOUT_REQUEST,
1243                                                  lu->login_id, NULL);
1244                 }
1245                 fw_core_remove_address_handler(&lu->address_handler);
1246                 list_del(&lu->link);
1247                 kfree(lu);
1248         }
1249         scsi_remove_host(shost);
1250         dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1251
1252         scsi_host_put(shost);
1253 }
1254
1255 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1256 #define SBP2_SW_VERSION_ENTRY   0x00010483
1257
1258 static const struct ieee1394_device_id sbp2_id_table[] = {
1259         {
1260                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1261                                 IEEE1394_MATCH_VERSION,
1262                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1263                 .version      = SBP2_SW_VERSION_ENTRY,
1264         },
1265         { }
1266 };
1267
1268 static struct fw_driver sbp2_driver = {
1269         .driver   = {
1270                 .owner  = THIS_MODULE,
1271                 .name   = KBUILD_MODNAME,
1272                 .bus    = &fw_bus_type,
1273         },
1274         .probe    = sbp2_probe,
1275         .update   = sbp2_update,
1276         .remove   = sbp2_remove,
1277         .id_table = sbp2_id_table,
1278 };
1279
1280 static void sbp2_unmap_scatterlist(struct device *card_device,
1281                                    struct sbp2_command_orb *orb)
1282 {
1283         scsi_dma_unmap(orb->cmd);
1284
1285         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1286                 dma_unmap_single(card_device, orb->page_table_bus,
1287                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1288 }
1289
1290 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1291 {
1292         int sam_status;
1293         int sfmt = (sbp2_status[0] >> 6) & 0x03;
1294
1295         if (sfmt == 2 || sfmt == 3) {
1296                 /*
1297                  * Reserved for future standardization (2) or
1298                  * Status block format vendor-dependent (3)
1299                  */
1300                 return DID_ERROR << 16;
1301         }
1302
1303         sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1304         sense_data[1] = 0x0;
1305         sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1306         sense_data[3] = sbp2_status[4];
1307         sense_data[4] = sbp2_status[5];
1308         sense_data[5] = sbp2_status[6];
1309         sense_data[6] = sbp2_status[7];
1310         sense_data[7] = 10;
1311         sense_data[8] = sbp2_status[8];
1312         sense_data[9] = sbp2_status[9];
1313         sense_data[10] = sbp2_status[10];
1314         sense_data[11] = sbp2_status[11];
1315         sense_data[12] = sbp2_status[2];
1316         sense_data[13] = sbp2_status[3];
1317         sense_data[14] = sbp2_status[12];
1318         sense_data[15] = sbp2_status[13];
1319
1320         sam_status = sbp2_status[0] & 0x3f;
1321
1322         switch (sam_status) {
1323         case SAM_STAT_GOOD:
1324         case SAM_STAT_CHECK_CONDITION:
1325         case SAM_STAT_CONDITION_MET:
1326         case SAM_STAT_BUSY:
1327         case SAM_STAT_RESERVATION_CONFLICT:
1328         case SAM_STAT_COMMAND_TERMINATED:
1329                 return DID_OK << 16 | sam_status;
1330
1331         default:
1332                 return DID_ERROR << 16;
1333         }
1334 }
1335
1336 static void complete_command_orb(struct sbp2_orb *base_orb,
1337                                  struct sbp2_status *status)
1338 {
1339         struct sbp2_command_orb *orb =
1340                 container_of(base_orb, struct sbp2_command_orb, base);
1341         struct fw_device *device = target_parent_device(base_orb->lu->tgt);
1342         int result;
1343
1344         if (status != NULL) {
1345                 if (STATUS_GET_DEAD(*status))
1346                         sbp2_agent_reset_no_wait(base_orb->lu);
1347
1348                 switch (STATUS_GET_RESPONSE(*status)) {
1349                 case SBP2_STATUS_REQUEST_COMPLETE:
1350                         result = DID_OK << 16;
1351                         break;
1352                 case SBP2_STATUS_TRANSPORT_FAILURE:
1353                         result = DID_BUS_BUSY << 16;
1354                         break;
1355                 case SBP2_STATUS_ILLEGAL_REQUEST:
1356                 case SBP2_STATUS_VENDOR_DEPENDENT:
1357                 default:
1358                         result = DID_ERROR << 16;
1359                         break;
1360                 }
1361
1362                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1363                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1364                                                            orb->cmd->sense_buffer);
1365         } else {
1366                 /*
1367                  * If the orb completes with status == NULL, something
1368                  * went wrong, typically a bus reset happened mid-orb
1369                  * or when sending the write (less likely).
1370                  */
1371                 result = DID_BUS_BUSY << 16;
1372                 sbp2_conditionally_block(base_orb->lu);
1373         }
1374
1375         dma_unmap_single(device->card->device, orb->base.request_bus,
1376                          sizeof(orb->request), DMA_TO_DEVICE);
1377         sbp2_unmap_scatterlist(device->card->device, orb);
1378
1379         orb->cmd->result = result;
1380         scsi_done(orb->cmd);
1381 }
1382
1383 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1384                 struct fw_device *device, struct sbp2_logical_unit *lu)
1385 {
1386         struct scatterlist *sg = scsi_sglist(orb->cmd);
1387         int i, n;
1388
1389         n = scsi_dma_map(orb->cmd);
1390         if (n <= 0)
1391                 goto fail;
1392
1393         /*
1394          * Handle the special case where there is only one element in
1395          * the scatter list by converting it to an immediate block
1396          * request. This is also a workaround for broken devices such
1397          * as the second generation iPod which doesn't support page
1398          * tables.
1399          */
1400         if (n == 1) {
1401                 orb->request.data_descriptor.high =
1402                         cpu_to_be32(lu->tgt->address_high);
1403                 orb->request.data_descriptor.low  =
1404                         cpu_to_be32(sg_dma_address(sg));
1405                 orb->request.misc |=
1406                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1407                 return 0;
1408         }
1409
1410         for_each_sg(sg, sg, n, i) {
1411                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1412                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1413         }
1414
1415         orb->page_table_bus =
1416                 dma_map_single(device->card->device, orb->page_table,
1417                                sizeof(orb->page_table), DMA_TO_DEVICE);
1418         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1419                 goto fail_page_table;
1420
1421         /*
1422          * The data_descriptor pointer is the one case where we need
1423          * to fill in the node ID part of the address.  All other
1424          * pointers assume that the data referenced reside on the
1425          * initiator (i.e. us), but data_descriptor can refer to data
1426          * on other nodes so we need to put our ID in descriptor.high.
1427          */
1428         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1429         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1430         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1431                                          COMMAND_ORB_DATA_SIZE(n));
1432
1433         return 0;
1434
1435  fail_page_table:
1436         scsi_dma_unmap(orb->cmd);
1437  fail:
1438         return -ENOMEM;
1439 }
1440
1441 /* SCSI stack integration */
1442
1443 static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1444                                   struct scsi_cmnd *cmd)
1445 {
1446         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1447         struct fw_device *device = target_parent_device(lu->tgt);
1448         struct sbp2_command_orb *orb;
1449         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1450
1451         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1452         if (orb == NULL)
1453                 return SCSI_MLQUEUE_HOST_BUSY;
1454
1455         /* Initialize rcode to something not RCODE_COMPLETE. */
1456         orb->base.rcode = -1;
1457         kref_init(&orb->base.kref);
1458         orb->cmd = cmd;
1459         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1460         orb->request.misc = cpu_to_be32(
1461                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1462                 COMMAND_ORB_SPEED(device->max_speed) |
1463                 COMMAND_ORB_NOTIFY);
1464
1465         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1466                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1467
1468         generation = device->generation;
1469         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1470
1471         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1472                 goto out;
1473
1474         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1475
1476         orb->base.callback = complete_command_orb;
1477         orb->base.request_bus =
1478                 dma_map_single(device->card->device, &orb->request,
1479                                sizeof(orb->request), DMA_TO_DEVICE);
1480         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1481                 sbp2_unmap_scatterlist(device->card->device, orb);
1482                 goto out;
1483         }
1484
1485         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1486                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1487         retval = 0;
1488  out:
1489         kref_put(&orb->base.kref, free_orb);
1490         return retval;
1491 }
1492
1493 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1494 {
1495         struct sbp2_logical_unit *lu = sdev->hostdata;
1496
1497         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1498         if (!lu)
1499                 return -ENOSYS;
1500
1501         sdev->allow_restart = 1;
1502
1503         /*
1504          * SBP-2 does not require any alignment, but we set it anyway
1505          * for compatibility with earlier versions of this driver.
1506          */
1507         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1508
1509         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1510                 sdev->inquiry_len = 36;
1511
1512         return 0;
1513 }
1514
1515 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1516 {
1517         struct sbp2_logical_unit *lu = sdev->hostdata;
1518
1519         sdev->use_10_for_rw = 1;
1520
1521         if (sbp2_param_exclusive_login) {
1522                 sdev->manage_system_start_stop = 1;
1523                 sdev->manage_runtime_start_stop = 1;
1524                 sdev->manage_shutdown = 1;
1525         }
1526
1527         if (sdev->type == TYPE_ROM)
1528                 sdev->use_10_for_ms = 1;
1529
1530         if (sdev->type == TYPE_DISK &&
1531             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1532                 sdev->skip_ms_page_8 = 1;
1533
1534         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1535                 sdev->fix_capacity = 1;
1536
1537         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1538                 sdev->start_stop_pwr_cond = 1;
1539
1540         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1541                 blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1542
1543         return 0;
1544 }
1545
1546 /*
1547  * Called by scsi stack when something has really gone wrong.  Usually
1548  * called when a command has timed-out for some reason.
1549  */
1550 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1551 {
1552         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1553
1554         dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1555         sbp2_agent_reset(lu);
1556         sbp2_cancel_orbs(lu);
1557
1558         return SUCCESS;
1559 }
1560
1561 /*
1562  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1563  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1564  *
1565  * This is the concatenation of target port identifier and logical unit
1566  * identifier as per SAM-2...SAM-4 annex A.
1567  */
1568 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1569                         struct device_attribute *attr, char *buf)
1570 {
1571         struct scsi_device *sdev = to_scsi_device(dev);
1572         struct sbp2_logical_unit *lu;
1573
1574         if (!sdev)
1575                 return 0;
1576
1577         lu = sdev->hostdata;
1578
1579         return sprintf(buf, "%016llx:%06x:%04x\n",
1580                         (unsigned long long)lu->tgt->guid,
1581                         lu->tgt->directory_id, lu->lun);
1582 }
1583
1584 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1585
1586 static struct attribute *sbp2_scsi_sysfs_attrs[] = {
1587         &dev_attr_ieee1394_id.attr,
1588         NULL
1589 };
1590
1591 ATTRIBUTE_GROUPS(sbp2_scsi_sysfs);
1592
1593 static const struct scsi_host_template scsi_driver_template = {
1594         .module                 = THIS_MODULE,
1595         .name                   = "SBP-2 IEEE-1394",
1596         .proc_name              = "sbp2",
1597         .queuecommand           = sbp2_scsi_queuecommand,
1598         .slave_alloc            = sbp2_scsi_slave_alloc,
1599         .slave_configure        = sbp2_scsi_slave_configure,
1600         .eh_abort_handler       = sbp2_scsi_abort,
1601         .this_id                = -1,
1602         .sg_tablesize           = SG_ALL,
1603         .max_segment_size       = SBP2_MAX_SEG_SIZE,
1604         .can_queue              = 1,
1605         .sdev_groups            = sbp2_scsi_sysfs_groups,
1606 };
1607
1608 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1609 MODULE_DESCRIPTION("SCSI over IEEE1394");
1610 MODULE_LICENSE("GPL");
1611 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1612
1613 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1614 MODULE_ALIAS("sbp2");
1615
1616 static int __init sbp2_init(void)
1617 {
1618         return driver_register(&sbp2_driver.driver);
1619 }
1620
1621 static void __exit sbp2_cleanup(void)
1622 {
1623         driver_unregister(&sbp2_driver.driver);
1624 }
1625
1626 module_init(sbp2_init);
1627 module_exit(sbp2_cleanup);