drivers/firewire/sbp2.c

   1 /*
   2  * SBP2 driver (SCSI over IEEE1394)
   3  *
   4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22  * The basic structure of this driver is based on the old storage driver,
  23  * drivers/ieee1394/sbp2.c, originally written by
  24  *     James Goodwin <jamesg@filanet.com>
  25  * with later contributions and ongoing maintenance from
  26  *     Ben Collins <bcollins@debian.org>,
  27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  28  * and many others.
  29  */
  30
  31 #include <linux/blkdev.h>
  32 #include <linux/bug.h>
  33 #include <linux/completion.h>
  34 #include <linux/delay.h>
  35 #include <linux/device.h>
  36 #include <linux/dma-mapping.h>
  37 #include <linux/firewire.h>
  38 #include <linux/firewire-constants.h>
  39 #include <linux/init.h>
  40 #include <linux/jiffies.h>
  41 #include <linux/kernel.h>
  42 #include <linux/kref.h>
  43 #include <linux/list.h>
  44 #include <linux/mod_devicetable.h>
  45 #include <linux/module.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/scatterlist.h>
  48 #include <linux/slab.h>
  49 #include <linux/spinlock.h>
  50 #include <linux/string.h>
  51 #include <linux/stringify.h>
  52 #include <linux/workqueue.h>
  53
  54 #include <asm/byteorder.h>
  55
  56 #include <scsi/scsi.h>
  57 #include <scsi/scsi_cmnd.h>
  58 #include <scsi/scsi_device.h>
  59 #include <scsi/scsi_host.h>
  60
  61 /*
  62  * So far only bridges from Oxford Semiconductor are known to support
  63  * concurrent logins. Depending on firmware, four or two concurrent logins
  64  * are possible on OXFW911 and newer Oxsemi bridges.
  65  *
  66  * Concurrent logins are useful together with cluster filesystems.
  67  */
  68 static bool sbp2_param_exclusive_login = 1;
  69 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  70 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  71                  "(default = Y, use N for concurrent initiators)");
  72
  73 /*
  74  * Flags for firmware oddities
  75  *
  76  * - 128kB max transfer
  77  *   Limit transfer size. Necessary for some old bridges.
  78  *
  79  * - 36 byte inquiry
  80  *   When scsi_mod probes the device, let the inquiry command look like that
  81  *   from MS Windows.
  82  *
  83  * - skip mode page 8
  84  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  85  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  86  *
  87  * - fix capacity
  88  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  89  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  90  *   Don't use this with devices which don't have this bug.
  91  *
  92  * - delay inquiry
  93  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  94  *
  95  * - power condition
  96  *   Set the power condition field in the START STOP UNIT commands sent by
  97  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  98  *   Some disks need this to spin down or to resume properly.
  99  *
 100  * - override internal blacklist
 101  *   Instead of adding to the built-in blacklist, use only the workarounds
 102  *   specified in the module load parameter.
 103  *   Useful if a blacklist entry interfered with a non-broken device.
 104  */
 105 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 106 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 107 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 108 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 109 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 110 #define SBP2_INQUIRY_DELAY              12
 111 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 112 #define SBP2_WORKAROUND_OVERRIDE        0x100
 113
 114 static int sbp2_param_workarounds;
 115 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 116 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 117         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 118         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 119         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 120         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 121         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 122         ", set power condition in start stop unit = "
 123                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 124         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 125         ", or a combination)");
 126
 127 /*
 128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 129  * and one struct scsi_device per sbp2_logical_unit.
 130  */
 131 struct sbp2_logical_unit {
 132         struct sbp2_target *tgt;
 133         struct list_head link;
 134         struct fw_address_handler address_handler;
 135         struct list_head orb_list;
 136
 137         u64 command_block_agent_address;
 138         u16 lun;
 139         int login_id;
 140
 141         /*
 142          * The generation is updated once we've logged in or reconnected
 143          * to the logical unit.  Thus, I/O to the device will automatically
 144          * fail and get retried if it happens in a window where the device
 145          * is not ready, e.g. after a bus reset but before we reconnect.
 146          */
 147         int generation;
 148         int retries;
 149         struct delayed_work work;
 150         bool has_sdev;
 151         bool blocked;
 152 };
 153
 154 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 155 {
 156         queue_delayed_work(fw_workqueue, &lu->work, delay);
 157 }
 158
 159 /*
 160  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 161  * and one struct Scsi_Host per sbp2_target.
 162  */
 163 struct sbp2_target {
 164         struct fw_unit *unit;
 165         struct list_head lu_list;
 166
 167         u64 management_agent_address;
 168         u64 guid;
 169         int directory_id;
 170         int node_id;
 171         int address_high;
 172         unsigned int workarounds;
 173         unsigned int mgt_orb_timeout;
 174         unsigned int max_payload;
 175
 176         int dont_block; /* counter for each logical unit */
 177         int blocked;    /* ditto */
 178 };
 179
 180 static struct fw_device *target_parent_device(struct sbp2_target *tgt)
 181 {
 182         return fw_parent_device(tgt->unit);
 183 }
 184
 185 static const struct device *tgt_dev(const struct sbp2_target *tgt)
 186 {
 187         return &tgt->unit->device;
 188 }
 189
 190 static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
 191 {
 192         return &lu->tgt->unit->device;
 193 }
 194
 195 /* Impossible login_id, to detect logout attempt before successful login */
 196 #define INVALID_LOGIN_ID 0x10000
 197
 198 #define SBP2_ORB_TIMEOUT                2000U           /* Timeout in ms */
 199 #define SBP2_ORB_NULL                   0x80000000
 200 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 201 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 202
 203 /*
 204  * There is no transport protocol limit to the CDB length,  but we implement
 205  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
 206  */
 207 #define SBP2_MAX_CDB_SIZE               16
 208
 209 /*
 210  * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
 211  * for compatibility with earlier versions of this driver.
 212  */
 213 #define SBP2_MAX_SEG_SIZE               0xfffc
 214
 215 /* Unit directory keys */
 216 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 217 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 218 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 219 #define SBP2_CSR_UNIT_UNIQUE_ID         0x8d
 220 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 221
 222 /* Management orb opcodes */
 223 #define SBP2_LOGIN_REQUEST              0x0
 224 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 225 #define SBP2_RECONNECT_REQUEST          0x3
 226 #define SBP2_SET_PASSWORD_REQUEST       0x4
 227 #define SBP2_LOGOUT_REQUEST             0x7
 228 #define SBP2_ABORT_TASK_REQUEST         0xb
 229 #define SBP2_ABORT_TASK_SET             0xc
 230 #define SBP2_LOGICAL_UNIT_RESET         0xe
 231 #define SBP2_TARGET_RESET_REQUEST       0xf
 232
 233 /* Offsets for command block agent registers */
 234 #define SBP2_AGENT_STATE                0x00
 235 #define SBP2_AGENT_RESET                0x04
 236 #define SBP2_ORB_POINTER                0x08
 237 #define SBP2_DOORBELL                   0x10
 238 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 239
 240 /* Status write response codes */
 241 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 242 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 243 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 244 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 245
 246 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 247 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 248 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 249 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 250 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 251 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 252 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 253 #define STATUS_GET_DATA(v)              ((v).data)
 254
 255 struct sbp2_status {
 256         u32 status;
 257         u32 orb_low;
 258         u8 data[24];
 259 };
 260
 261 struct sbp2_pointer {
 262         __be32 high;
 263         __be32 low;
 264 };
 265
 266 struct sbp2_orb {
 267         struct fw_transaction t;
 268         struct kref kref;
 269         dma_addr_t request_bus;
 270         int rcode;
 271         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 272         struct list_head link;
 273 };
 274
 275 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 276 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 277 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 278 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 279 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 280 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 281
 282 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 283 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 284
 285 struct sbp2_management_orb {
 286         struct sbp2_orb base;
 287         struct {
 288                 struct sbp2_pointer password;
 289                 struct sbp2_pointer response;
 290                 __be32 misc;
 291                 __be32 length;
 292                 struct sbp2_pointer status_fifo;
 293         } request;
 294         __be32 response[4];
 295         dma_addr_t response_bus;
 296         struct completion done;
 297         struct sbp2_status status;
 298 };
 299
 300 struct sbp2_login_response {
 301         __be32 misc;
 302         struct sbp2_pointer command_block_agent;
 303         __be32 reconnect_hold;
 304 };
 305 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 306 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 307 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 308 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 309 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 310 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 311 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 312 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 313
 314 struct sbp2_command_orb {
 315         struct sbp2_orb base;
 316         struct {
 317                 struct sbp2_pointer next;
 318                 struct sbp2_pointer data_descriptor;
 319                 __be32 misc;
 320                 u8 command_block[SBP2_MAX_CDB_SIZE];
 321         } request;
 322         struct scsi_cmnd *cmd;
 323         struct sbp2_logical_unit *lu;
 324
 325         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 326         dma_addr_t page_table_bus;
 327 };
 328
 329 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 330 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 331
 332 /*
 333  * List of devices with known bugs.
 334  *
 335  * The firmware_revision field, masked with 0xffff00, is the best
 336  * indicator for the type of bridge chip of a device.  It yields a few
 337  * false positives but this did not break correctly behaving devices
 338  * so far.
 339  */
 340 static const struct {
 341         u32 firmware_revision;
 342         u32 model;
 343         unsigned int workarounds;
 344 } sbp2_workarounds_table[] = {
 345         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 346                 .firmware_revision      = 0x002800,
 347                 .model                  = 0x001010,
 348                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 349                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 350                                           SBP2_WORKAROUND_POWER_CONDITION,
 351         },
 352         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 353                 .firmware_revision      = 0x002800,
 354                 .model                  = 0x000000,
 355                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 356         },
 357         /* Initio bridges, actually only needed for some older ones */ {
 358                 .firmware_revision      = 0x000200,
 359                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 360                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 361         },
 362         /* PL-3507 bridge with Prolific firmware */ {
 363                 .firmware_revision      = 0x012800,
 364                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 365                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 366         },
 367         /* Symbios bridge */ {
 368                 .firmware_revision      = 0xa0b800,
 369                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 370                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 371         },
 372         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 373                 .firmware_revision      = 0x002600,
 374                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 375                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 376         },
 377         /*
 378          * iPod 2nd generation: needs 128k max transfer size workaround
 379          * iPod 3rd generation: needs fix capacity workaround
 380          */
 381         {
 382                 .firmware_revision      = 0x0a2700,
 383                 .model                  = 0x000000,
 384                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 385                                           SBP2_WORKAROUND_FIX_CAPACITY,
 386         },
 387         /* iPod 4th generation */ {
 388                 .firmware_revision      = 0x0a2700,
 389                 .model                  = 0x000021,
 390                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 391         },
 392         /* iPod mini */ {
 393                 .firmware_revision      = 0x0a2700,
 394                 .model                  = 0x000022,
 395                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 396         },
 397         /* iPod mini */ {
 398                 .firmware_revision      = 0x0a2700,
 399                 .model                  = 0x000023,
 400                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 401         },
 402         /* iPod Photo */ {
 403                 .firmware_revision      = 0x0a2700,
 404                 .model                  = 0x00007e,
 405                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 406         }
 407 };
 408
 409 static void free_orb(struct kref *kref)
 410 {
 411         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 412
 413         kfree(orb);
 414 }
 415
 416 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 417                               int tcode, int destination, int source,
 418                               int generation, unsigned long long offset,
 419                               void *payload, size_t length, void *callback_data)
 420 {
 421         struct sbp2_logical_unit *lu = callback_data;
 422         struct sbp2_orb *orb;
 423         struct sbp2_status status;
 424         unsigned long flags;
 425
 426         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 427             length < 8 || length > sizeof(status)) {
 428                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 429                 return;
 430         }
 431
 432         status.status  = be32_to_cpup(payload);
 433         status.orb_low = be32_to_cpup(payload + 4);
 434         memset(status.data, 0, sizeof(status.data));
 435         if (length > 8)
 436                 memcpy(status.data, payload + 8, length - 8);
 437
 438         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 439                 dev_notice(lu_dev(lu),
 440                            "non-ORB related status write, not handled\n");
 441                 fw_send_response(card, request, RCODE_COMPLETE);
 442                 return;
 443         }
 444
 445         /* Lookup the orb corresponding to this status write. */
 446         spin_lock_irqsave(&card->lock, flags);
 447         list_for_each_entry(orb, &lu->orb_list, link) {
 448                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 449                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 450                         orb->rcode = RCODE_COMPLETE;
 451                         list_del(&orb->link);
 452                         break;
 453                 }
 454         }
 455         spin_unlock_irqrestore(&card->lock, flags);
 456
 457         if (&orb->link != &lu->orb_list) {
 458                 orb->callback(orb, &status);
 459                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 460         } else {
 461                 dev_err(lu_dev(lu), "status write for unknown ORB\n");
 462         }
 463
 464         fw_send_response(card, request, RCODE_COMPLETE);
 465 }
 466
 467 static void complete_transaction(struct fw_card *card, int rcode,
 468                                  void *payload, size_t length, void *data)
 469 {
 470         struct sbp2_orb *orb = data;
 471         unsigned long flags;
 472
 473         /*
 474          * This is a little tricky.  We can get the status write for
 475          * the orb before we get this callback.  The status write
 476          * handler above will assume the orb pointer transaction was
 477          * successful and set the rcode to RCODE_COMPLETE for the orb.
 478          * So this callback only sets the rcode if it hasn't already
 479          * been set and only does the cleanup if the transaction
 480          * failed and we didn't already get a status write.
 481          */
 482         spin_lock_irqsave(&card->lock, flags);
 483
 484         if (orb->rcode == -1)
 485                 orb->rcode = rcode;
 486         if (orb->rcode != RCODE_COMPLETE) {
 487                 list_del(&orb->link);
 488                 spin_unlock_irqrestore(&card->lock, flags);
 489
 490                 orb->callback(orb, NULL);
 491                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 492         } else {
 493                 spin_unlock_irqrestore(&card->lock, flags);
 494         }
 495
 496         kref_put(&orb->kref, free_orb); /* transaction callback reference */
 497 }
 498
 499 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 500                           int node_id, int generation, u64 offset)
 501 {
 502         struct fw_device *device = target_parent_device(lu->tgt);
 503         struct sbp2_pointer orb_pointer;
 504         unsigned long flags;
 505
 506         orb_pointer.high = 0;
 507         orb_pointer.low = cpu_to_be32(orb->request_bus);
 508
 509         spin_lock_irqsave(&device->card->lock, flags);
 510         list_add_tail(&orb->link, &lu->orb_list);
 511         spin_unlock_irqrestore(&device->card->lock, flags);
 512
 513         kref_get(&orb->kref); /* transaction callback reference */
 514         kref_get(&orb->kref); /* orb callback reference */
 515
 516         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 517                         node_id, generation, device->max_speed, offset,
 518                         &orb_pointer, 8, complete_transaction, orb);
 519 }
 520
 521 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 522 {
 523         struct fw_device *device = target_parent_device(lu->tgt);
 524         struct sbp2_orb *orb, *next;
 525         struct list_head list;
 526         unsigned long flags;
 527         int retval = -ENOENT;
 528
 529         INIT_LIST_HEAD(&list);
 530         spin_lock_irqsave(&device->card->lock, flags);
 531         list_splice_init(&lu->orb_list, &list);
 532         spin_unlock_irqrestore(&device->card->lock, flags);
 533
 534         list_for_each_entry_safe(orb, next, &list, link) {
 535                 retval = 0;
 536                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 537                         continue;
 538
 539                 orb->rcode = RCODE_CANCELLED;
 540                 orb->callback(orb, NULL);
 541                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 542         }
 543
 544         return retval;
 545 }
 546
 547 static void complete_management_orb(struct sbp2_orb *base_orb,
 548                                     struct sbp2_status *status)
 549 {
 550         struct sbp2_management_orb *orb =
 551                 container_of(base_orb, struct sbp2_management_orb, base);
 552
 553         if (status)
 554                 memcpy(&orb->status, status, sizeof(*status));
 555         complete(&orb->done);
 556 }
 557
 558 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 559                                     int generation, int function,
 560                                     int lun_or_login_id, void *response)
 561 {
 562         struct fw_device *device = target_parent_device(lu->tgt);
 563         struct sbp2_management_orb *orb;
 564         unsigned int timeout;
 565         int retval = -ENOMEM;
 566
 567         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 568                 return 0;
 569
 570         orb = kzalloc(sizeof(*orb), GFP_NOIO);
 571         if (orb == NULL)
 572                 return -ENOMEM;
 573
 574         kref_init(&orb->base.kref);
 575         orb->response_bus =
 576                 dma_map_single(device->card->device, &orb->response,
 577                                sizeof(orb->response), DMA_FROM_DEVICE);
 578         if (dma_mapping_error(device->card->device, orb->response_bus))
 579                 goto fail_mapping_response;
 580
 581         orb->request.response.high = 0;
 582         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 583
 584         orb->request.misc = cpu_to_be32(
 585                 MANAGEMENT_ORB_NOTIFY |
 586                 MANAGEMENT_ORB_FUNCTION(function) |
 587                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 588         orb->request.length = cpu_to_be32(
 589                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 590
 591         orb->request.status_fifo.high =
 592                 cpu_to_be32(lu->address_handler.offset >> 32);
 593         orb->request.status_fifo.low  =
 594                 cpu_to_be32(lu->address_handler.offset);
 595
 596         if (function == SBP2_LOGIN_REQUEST) {
 597                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 598                 orb->request.misc |= cpu_to_be32(
 599                         MANAGEMENT_ORB_RECONNECT(2) |
 600                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 601                 timeout = lu->tgt->mgt_orb_timeout;
 602         } else {
 603                 timeout = SBP2_ORB_TIMEOUT;
 604         }
 605
 606         init_completion(&orb->done);
 607         orb->base.callback = complete_management_orb;
 608
 609         orb->base.request_bus =
 610                 dma_map_single(device->card->device, &orb->request,
 611                                sizeof(orb->request), DMA_TO_DEVICE);
 612         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 613                 goto fail_mapping_request;
 614
 615         sbp2_send_orb(&orb->base, lu, node_id, generation,
 616                       lu->tgt->management_agent_address);
 617
 618         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 619
 620         retval = -EIO;
 621         if (sbp2_cancel_orbs(lu) == 0) {
 622                 dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
 623                         orb->base.rcode);
 624                 goto out;
 625         }
 626
 627         if (orb->base.rcode != RCODE_COMPLETE) {
 628                 dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
 629                         orb->base.rcode);
 630                 goto out;
 631         }
 632
 633         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 634             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 635                 dev_err(lu_dev(lu), "error status: %d:%d\n",
 636                          STATUS_GET_RESPONSE(orb->status),
 637                          STATUS_GET_SBP_STATUS(orb->status));
 638                 goto out;
 639         }
 640
 641         retval = 0;
 642  out:
 643         dma_unmap_single(device->card->device, orb->base.request_bus,
 644                          sizeof(orb->request), DMA_TO_DEVICE);
 645  fail_mapping_request:
 646         dma_unmap_single(device->card->device, orb->response_bus,
 647                          sizeof(orb->response), DMA_FROM_DEVICE);
 648  fail_mapping_response:
 649         if (response)
 650                 memcpy(response, orb->response, sizeof(orb->response));
 651         kref_put(&orb->base.kref, free_orb);
 652
 653         return retval;
 654 }
 655
 656 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 657 {
 658         struct fw_device *device = target_parent_device(lu->tgt);
 659         __be32 d = 0;
 660
 661         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 662                            lu->tgt->node_id, lu->generation, device->max_speed,
 663                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 664                            &d, 4);
 665 }
 666
 667 static void complete_agent_reset_write_no_wait(struct fw_card *card,
 668                 int rcode, void *payload, size_t length, void *data)
 669 {
 670         kfree(data);
 671 }
 672
 673 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 674 {
 675         struct fw_device *device = target_parent_device(lu->tgt);
 676         struct fw_transaction *t;
 677         static __be32 d;
 678
 679         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 680         if (t == NULL)
 681                 return;
 682
 683         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 684                         lu->tgt->node_id, lu->generation, device->max_speed,
 685                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 686                         &d, 4, complete_agent_reset_write_no_wait, t);
 687 }
 688
 689 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 690 {
 691         /*
 692          * We may access dont_block without taking card->lock here:
 693          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 694          * are currently serialized against each other.
 695          * And a wrong result in sbp2_conditionally_block()'s access of
 696          * dont_block is rather harmless, it simply misses its first chance.
 697          */
 698         --lu->tgt->dont_block;
 699 }
 700
 701 /*
 702  * Blocks lu->tgt if all of the following conditions are met:
 703  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 704  *     logical units have been finished (indicated by dont_block == 0).
 705  *   - lu->generation is stale.
 706  *
 707  * Note, scsi_block_requests() must be called while holding card->lock,
 708  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 709  * unblock the target.
 710  */
 711 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 712 {
 713         struct sbp2_target *tgt = lu->tgt;
 714         struct fw_card *card = target_parent_device(tgt)->card;
 715         struct Scsi_Host *shost =
 716                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 717         unsigned long flags;
 718
 719         spin_lock_irqsave(&card->lock, flags);
 720         if (!tgt->dont_block && !lu->blocked &&
 721             lu->generation != card->generation) {
 722                 lu->blocked = true;
 723                 if (++tgt->blocked == 1)
 724                         scsi_block_requests(shost);
 725         }
 726         spin_unlock_irqrestore(&card->lock, flags);
 727 }
 728
 729 /*
 730  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 731  * Note, it is harmless to run scsi_unblock_requests() outside the
 732  * card->lock protected section.  On the other hand, running it inside
 733  * the section might clash with shost->host_lock.
 734  */
 735 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 736 {
 737         struct sbp2_target *tgt = lu->tgt;
 738         struct fw_card *card = target_parent_device(tgt)->card;
 739         struct Scsi_Host *shost =
 740                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 741         unsigned long flags;
 742         bool unblock = false;
 743
 744         spin_lock_irqsave(&card->lock, flags);
 745         if (lu->blocked && lu->generation == card->generation) {
 746                 lu->blocked = false;
 747                 unblock = --tgt->blocked == 0;
 748         }
 749         spin_unlock_irqrestore(&card->lock, flags);
 750
 751         if (unblock)
 752                 scsi_unblock_requests(shost);
 753 }
 754
 755 /*
 756  * Prevents future blocking of tgt and unblocks it.
 757  * Note, it is harmless to run scsi_unblock_requests() outside the
 758  * card->lock protected section.  On the other hand, running it inside
 759  * the section might clash with shost->host_lock.
 760  */
 761 static void sbp2_unblock(struct sbp2_target *tgt)
 762 {
 763         struct fw_card *card = target_parent_device(tgt)->card;
 764         struct Scsi_Host *shost =
 765                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 766         unsigned long flags;
 767
 768         spin_lock_irqsave(&card->lock, flags);
 769         ++tgt->dont_block;
 770         spin_unlock_irqrestore(&card->lock, flags);
 771
 772         scsi_unblock_requests(shost);
 773 }
 774
 775 static int sbp2_lun2int(u16 lun)
 776 {
 777         struct scsi_lun eight_bytes_lun;
 778
 779         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 780         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 781         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 782
 783         return scsilun_to_int(&eight_bytes_lun);
 784 }
 785
 786 /*
 787  * Write retransmit retry values into the BUSY_TIMEOUT register.
 788  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 789  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 790  *   saner value after logging into the device.
 791  * - The dual-phase retry protocol is optional to implement, and if not
 792  *   supported, writes to the dual-phase portion of the register will be
 793  *   ignored. We try to write the original 1394-1995 default here.
 794  * - In the case of devices that are also SBP-3-compliant, all writes are
 795  *   ignored, as the register is read-only, but contains single-phase retry of
 796  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 797  *   write attempt is safe and yields more consistent behavior for all devices.
 798  *
 799  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 800  * and section 6.4 of the SBP-3 spec for further details.
 801  */
 802 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 803 {
 804         struct fw_device *device = target_parent_device(lu->tgt);
 805         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 806
 807         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 808                            lu->tgt->node_id, lu->generation, device->max_speed,
 809                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
 810 }
 811
 812 static void sbp2_reconnect(struct work_struct *work);
 813
 814 static void sbp2_login(struct work_struct *work)
 815 {
 816         struct sbp2_logical_unit *lu =
 817                 container_of(work, struct sbp2_logical_unit, work.work);
 818         struct sbp2_target *tgt = lu->tgt;
 819         struct fw_device *device = target_parent_device(tgt);
 820         struct Scsi_Host *shost;
 821         struct scsi_device *sdev;
 822         struct sbp2_login_response response;
 823         int generation, node_id, local_node_id;
 824
 825         if (fw_device_is_shutdown(device))
 826                 return;
 827
 828         generation    = device->generation;
 829         smp_rmb();    /* node IDs must not be older than generation */
 830         node_id       = device->node_id;
 831         local_node_id = device->card->node_id;
 832
 833         /* If this is a re-login attempt, log out, or we might be rejected. */
 834         if (lu->has_sdev)
 835                 sbp2_send_management_orb(lu, device->node_id, generation,
 836                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 837
 838         if (sbp2_send_management_orb(lu, node_id, generation,
 839                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 840                 if (lu->retries++ < 5) {
 841                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 842                 } else {
 843                         dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
 844                                 lu->lun);
 845                         /* Let any waiting I/O fail from now on. */
 846                         sbp2_unblock(lu->tgt);
 847                 }
 848                 return;
 849         }
 850
 851         tgt->node_id      = node_id;
 852         tgt->address_high = local_node_id << 16;
 853         smp_wmb();        /* node IDs must not be older than generation */
 854         lu->generation    = generation;
 855
 856         lu->command_block_agent_address =
 857                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 858                       << 32) | be32_to_cpu(response.command_block_agent.low);
 859         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 860
 861         dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
 862                    lu->lun, lu->retries);
 863
 864         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 865         sbp2_set_busy_timeout(lu);
 866
 867         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 868         sbp2_agent_reset(lu);
 869
 870         /* This was a re-login. */
 871         if (lu->has_sdev) {
 872                 sbp2_cancel_orbs(lu);
 873                 sbp2_conditionally_unblock(lu);
 874
 875                 return;
 876         }
 877
 878         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 879                 ssleep(SBP2_INQUIRY_DELAY);
 880
 881         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 882         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 883         /*
 884          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 885          * Therefore __scsi_add_device() will get into trouble if a bus reset
 886          * happens in parallel.  It will either fail or leave us with an
 887          * unusable sdev.  As a workaround we check for this and retry the
 888          * whole login and SCSI probing.
 889          */
 890
 891         /* Reported error during __scsi_add_device() */
 892         if (IS_ERR(sdev))
 893                 goto out_logout_login;
 894
 895         /* Unreported error during __scsi_add_device() */
 896         smp_rmb(); /* get current card generation */
 897         if (generation != device->card->generation) {
 898                 scsi_remove_device(sdev);
 899                 scsi_device_put(sdev);
 900                 goto out_logout_login;
 901         }
 902
 903         /* No error during __scsi_add_device() */
 904         lu->has_sdev = true;
 905         scsi_device_put(sdev);
 906         sbp2_allow_block(lu);
 907
 908         return;
 909
 910  out_logout_login:
 911         smp_rmb(); /* generation may have changed */
 912         generation = device->generation;
 913         smp_rmb(); /* node_id must not be older than generation */
 914
 915         sbp2_send_management_orb(lu, device->node_id, generation,
 916                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 917         /*
 918          * If a bus reset happened, sbp2_update will have requeued
 919          * lu->work already.  Reset the work from reconnect to login.
 920          */
 921         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 922 }
 923
 924 static void sbp2_reconnect(struct work_struct *work)
 925 {
 926         struct sbp2_logical_unit *lu =
 927                 container_of(work, struct sbp2_logical_unit, work.work);
 928         struct sbp2_target *tgt = lu->tgt;
 929         struct fw_device *device = target_parent_device(tgt);
 930         int generation, node_id, local_node_id;
 931
 932         if (fw_device_is_shutdown(device))
 933                 return;
 934
 935         generation    = device->generation;
 936         smp_rmb();    /* node IDs must not be older than generation */
 937         node_id       = device->node_id;
 938         local_node_id = device->card->node_id;
 939
 940         if (sbp2_send_management_orb(lu, node_id, generation,
 941                                      SBP2_RECONNECT_REQUEST,
 942                                      lu->login_id, NULL) < 0) {
 943                 /*
 944                  * If reconnect was impossible even though we are in the
 945                  * current generation, fall back and try to log in again.
 946                  *
 947                  * We could check for "Function rejected" status, but
 948                  * looking at the bus generation as simpler and more general.
 949                  */
 950                 smp_rmb(); /* get current card generation */
 951                 if (generation == device->card->generation ||
 952                     lu->retries++ >= 5) {
 953                         dev_err(tgt_dev(tgt), "failed to reconnect\n");
 954                         lu->retries = 0;
 955                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 956                 }
 957                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 958
 959                 return;
 960         }
 961
 962         tgt->node_id      = node_id;
 963         tgt->address_high = local_node_id << 16;
 964         smp_wmb();        /* node IDs must not be older than generation */
 965         lu->generation    = generation;
 966
 967         dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
 968                    lu->lun, lu->retries);
 969
 970         sbp2_agent_reset(lu);
 971         sbp2_cancel_orbs(lu);
 972         sbp2_conditionally_unblock(lu);
 973 }
 974
 975 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 976 {
 977         struct sbp2_logical_unit *lu;
 978
 979         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 980         if (!lu)
 981                 return -ENOMEM;
 982
 983         lu->address_handler.length           = 0x100;
 984         lu->address_handler.address_callback = sbp2_status_write;
 985         lu->address_handler.callback_data    = lu;
 986
 987         if (fw_core_add_address_handler(&lu->address_handler,
 988                                         &fw_high_memory_region) < 0) {
 989                 kfree(lu);
 990                 return -ENOMEM;
 991         }
 992
 993         lu->tgt      = tgt;
 994         lu->lun      = lun_entry & 0xffff;
 995         lu->login_id = INVALID_LOGIN_ID;
 996         lu->retries  = 0;
 997         lu->has_sdev = false;
 998         lu->blocked  = false;
 999         ++tgt->dont_block;
1000         INIT_LIST_HEAD(&lu->orb_list);
1001         INIT_DELAYED_WORK(&lu->work, sbp2_login);
1002
1003         list_add_tail(&lu->link, &tgt->lu_list);
1004         return 0;
1005 }
1006
1007 static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
1008                                     const u32 *leaf)
1009 {
1010         if ((leaf[0] & 0xffff0000) == 0x00020000)
1011                 tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1012 }
1013
1014 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1015                                       const u32 *directory)
1016 {
1017         struct fw_csr_iterator ci;
1018         int key, value;
1019
1020         fw_csr_iterator_init(&ci, directory);
1021         while (fw_csr_iterator_next(&ci, &key, &value))
1022                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1023                     sbp2_add_logical_unit(tgt, value) < 0)
1024                         return -ENOMEM;
1025         return 0;
1026 }
1027
1028 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1029                               u32 *model, u32 *firmware_revision)
1030 {
1031         struct fw_csr_iterator ci;
1032         int key, value;
1033
1034         fw_csr_iterator_init(&ci, directory);
1035         while (fw_csr_iterator_next(&ci, &key, &value)) {
1036                 switch (key) {
1037
1038                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1039                         tgt->management_agent_address =
1040                                         CSR_REGISTER_BASE + 4 * value;
1041                         break;
1042
1043                 case CSR_DIRECTORY_ID:
1044                         tgt->directory_id = value;
1045                         break;
1046
1047                 case CSR_MODEL:
1048                         *model = value;
1049                         break;
1050
1051                 case SBP2_CSR_FIRMWARE_REVISION:
1052                         *firmware_revision = value;
1053                         break;
1054
1055                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1056                         /* the timeout value is stored in 500ms units */
1057                         tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1058                         break;
1059
1060                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1061                         if (sbp2_add_logical_unit(tgt, value) < 0)
1062                                 return -ENOMEM;
1063                         break;
1064
1065                 case SBP2_CSR_UNIT_UNIQUE_ID:
1066                         sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1067                         break;
1068
1069                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1070                         /* Adjust for the increment in the iterator */
1071                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1072                                 return -ENOMEM;
1073                         break;
1074                 }
1075         }
1076         return 0;
1077 }
1078
1079 /*
1080  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1081  * provided in the config rom. Most devices do provide a value, which
1082  * we'll use for login management orbs, but with some sane limits.
1083  */
1084 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1085 {
1086         unsigned int timeout = tgt->mgt_orb_timeout;
1087
1088         if (timeout > 40000)
1089                 dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1090                            timeout / 1000);
1091
1092         tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1093 }
1094
1095 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1096                                   u32 firmware_revision)
1097 {
1098         int i;
1099         unsigned int w = sbp2_param_workarounds;
1100
1101         if (w)
1102                 dev_notice(tgt_dev(tgt),
1103                            "Please notify linux1394-devel@lists.sf.net "
1104                            "if you need the workarounds parameter\n");
1105
1106         if (w & SBP2_WORKAROUND_OVERRIDE)
1107                 goto out;
1108
1109         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1110
1111                 if (sbp2_workarounds_table[i].firmware_revision !=
1112                     (firmware_revision & 0xffffff00))
1113                         continue;
1114
1115                 if (sbp2_workarounds_table[i].model != model &&
1116                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1117                         continue;
1118
1119                 w |= sbp2_workarounds_table[i].workarounds;
1120                 break;
1121         }
1122  out:
1123         if (w)
1124                 dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1125                            "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1126                            w, firmware_revision, model);
1127         tgt->workarounds = w;
1128 }
1129
1130 static struct scsi_host_template scsi_driver_template;
1131 static int sbp2_remove(struct device *dev);
1132
1133 static int sbp2_probe(struct device *dev)
1134 {
1135         struct fw_unit *unit = fw_unit(dev);
1136         struct fw_device *device = fw_parent_device(unit);
1137         struct sbp2_target *tgt;
1138         struct sbp2_logical_unit *lu;
1139         struct Scsi_Host *shost;
1140         u32 model, firmware_revision;
1141
1142         /* cannot (or should not) handle targets on the local node */
1143         if (device->is_local)
1144                 return -ENODEV;
1145
1146         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1147                 BUG_ON(dma_set_max_seg_size(device->card->device,
1148                                             SBP2_MAX_SEG_SIZE));
1149
1150         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1151         if (shost == NULL)
1152                 return -ENOMEM;
1153
1154         tgt = (struct sbp2_target *)shost->hostdata;
1155         dev_set_drvdata(&unit->device, tgt);
1156         tgt->unit = unit;
1157         INIT_LIST_HEAD(&tgt->lu_list);
1158         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1159
1160         if (fw_device_enable_phys_dma(device) < 0)
1161                 goto fail_shost_put;
1162
1163         shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1164
1165         if (scsi_add_host_with_dma(shost, &unit->device,
1166                                    device->card->device) < 0)
1167                 goto fail_shost_put;
1168
1169         /* implicit directory ID */
1170         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1171                              + CSR_CONFIG_ROM) & 0xffffff;
1172
1173         firmware_revision = SBP2_ROM_VALUE_MISSING;
1174         model             = SBP2_ROM_VALUE_MISSING;
1175
1176         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1177                                &firmware_revision) < 0)
1178                 goto fail_remove;
1179
1180         sbp2_clamp_management_orb_timeout(tgt);
1181         sbp2_init_workarounds(tgt, model, firmware_revision);
1182
1183         /*
1184          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1185          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1186          * specifies the max payload size as 2 ^ (max_payload + 2), so
1187          * if we set this to max_speed + 7, we get the right value.
1188          */
1189         tgt->max_payload = min3(device->max_speed + 7, 10U,
1190                                 device->card->max_receive - 1);
1191
1192         /* Do the login in a workqueue so we can easily reschedule retries. */
1193         list_for_each_entry(lu, &tgt->lu_list, link)
1194                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1195
1196         return 0;
1197
1198  fail_remove:
1199         sbp2_remove(dev);
1200         return -ENOMEM;
1201
1202  fail_shost_put:
1203         scsi_host_put(shost);
1204         return -ENOMEM;
1205 }
1206
1207 static void sbp2_update(struct fw_unit *unit)
1208 {
1209         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1210         struct sbp2_logical_unit *lu;
1211
1212         fw_device_enable_phys_dma(fw_parent_device(unit));
1213
1214         /*
1215          * Fw-core serializes sbp2_update() against sbp2_remove().
1216          * Iteration over tgt->lu_list is therefore safe here.
1217          */
1218         list_for_each_entry(lu, &tgt->lu_list, link) {
1219                 sbp2_conditionally_block(lu);
1220                 lu->retries = 0;
1221                 sbp2_queue_work(lu, 0);
1222         }
1223 }
1224
1225 static int sbp2_remove(struct device *dev)
1226 {
1227         struct fw_unit *unit = fw_unit(dev);
1228         struct fw_device *device = fw_parent_device(unit);
1229         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1230         struct sbp2_logical_unit *lu, *next;
1231         struct Scsi_Host *shost =
1232                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1233         struct scsi_device *sdev;
1234
1235         /* prevent deadlocks */
1236         sbp2_unblock(tgt);
1237
1238         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1239                 cancel_delayed_work_sync(&lu->work);
1240                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1241                 if (sdev) {
1242                         scsi_remove_device(sdev);
1243                         scsi_device_put(sdev);
1244                 }
1245                 if (lu->login_id != INVALID_LOGIN_ID) {
1246                         int generation, node_id;
1247                         /*
1248                          * tgt->node_id may be obsolete here if we failed
1249                          * during initial login or after a bus reset where
1250                          * the topology changed.
1251                          */
1252                         generation = device->generation;
1253                         smp_rmb(); /* node_id vs. generation */
1254                         node_id    = device->node_id;
1255                         sbp2_send_management_orb(lu, node_id, generation,
1256                                                  SBP2_LOGOUT_REQUEST,
1257                                                  lu->login_id, NULL);
1258                 }
1259                 fw_core_remove_address_handler(&lu->address_handler);
1260                 list_del(&lu->link);
1261                 kfree(lu);
1262         }
1263         scsi_remove_host(shost);
1264         dev_notice(dev, "released target %d:0:0\n", shost->host_no);
1265
1266         scsi_host_put(shost);
1267         return 0;
1268 }
1269
1270 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1271 #define SBP2_SW_VERSION_ENTRY   0x00010483
1272
1273 static const struct ieee1394_device_id sbp2_id_table[] = {
1274         {
1275                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1276                                 IEEE1394_MATCH_VERSION,
1277                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1278                 .version      = SBP2_SW_VERSION_ENTRY,
1279         },
1280         { }
1281 };
1282
1283 static struct fw_driver sbp2_driver = {
1284         .driver   = {
1285                 .owner  = THIS_MODULE,
1286                 .name   = KBUILD_MODNAME,
1287                 .bus    = &fw_bus_type,
1288                 .probe  = sbp2_probe,
1289                 .remove = sbp2_remove,
1290         },
1291         .update   = sbp2_update,
1292         .id_table = sbp2_id_table,
1293 };
1294
1295 static void sbp2_unmap_scatterlist(struct device *card_device,
1296                                    struct sbp2_command_orb *orb)
1297 {
1298         scsi_dma_unmap(orb->cmd);
1299
1300         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1301                 dma_unmap_single(card_device, orb->page_table_bus,
1302                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1303 }
1304
1305 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1306 {
1307         int sam_status;
1308         int sfmt = (sbp2_status[0] >> 6) & 0x03;
1309
1310         if (sfmt == 2 || sfmt == 3) {
1311                 /*
1312                  * Reserved for future standardization (2) or
1313                  * Status block format vendor-dependent (3)
1314                  */
1315                 return DID_ERROR << 16;
1316         }
1317
1318         sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1319         sense_data[1] = 0x0;
1320         sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1321         sense_data[3] = sbp2_status[4];
1322         sense_data[4] = sbp2_status[5];
1323         sense_data[5] = sbp2_status[6];
1324         sense_data[6] = sbp2_status[7];
1325         sense_data[7] = 10;
1326         sense_data[8] = sbp2_status[8];
1327         sense_data[9] = sbp2_status[9];
1328         sense_data[10] = sbp2_status[10];
1329         sense_data[11] = sbp2_status[11];
1330         sense_data[12] = sbp2_status[2];
1331         sense_data[13] = sbp2_status[3];
1332         sense_data[14] = sbp2_status[12];
1333         sense_data[15] = sbp2_status[13];
1334
1335         sam_status = sbp2_status[0] & 0x3f;
1336
1337         switch (sam_status) {
1338         case SAM_STAT_GOOD:
1339         case SAM_STAT_CHECK_CONDITION:
1340         case SAM_STAT_CONDITION_MET:
1341         case SAM_STAT_BUSY:
1342         case SAM_STAT_RESERVATION_CONFLICT:
1343         case SAM_STAT_COMMAND_TERMINATED:
1344                 return DID_OK << 16 | sam_status;
1345
1346         default:
1347                 return DID_ERROR << 16;
1348         }
1349 }
1350
1351 static void complete_command_orb(struct sbp2_orb *base_orb,
1352                                  struct sbp2_status *status)
1353 {
1354         struct sbp2_command_orb *orb =
1355                 container_of(base_orb, struct sbp2_command_orb, base);
1356         struct fw_device *device = target_parent_device(orb->lu->tgt);
1357         int result;
1358
1359         if (status != NULL) {
1360                 if (STATUS_GET_DEAD(*status))
1361                         sbp2_agent_reset_no_wait(orb->lu);
1362
1363                 switch (STATUS_GET_RESPONSE(*status)) {
1364                 case SBP2_STATUS_REQUEST_COMPLETE:
1365                         result = DID_OK << 16;
1366                         break;
1367                 case SBP2_STATUS_TRANSPORT_FAILURE:
1368                         result = DID_BUS_BUSY << 16;
1369                         break;
1370                 case SBP2_STATUS_ILLEGAL_REQUEST:
1371                 case SBP2_STATUS_VENDOR_DEPENDENT:
1372                 default:
1373                         result = DID_ERROR << 16;
1374                         break;
1375                 }
1376
1377                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1378                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1379                                                            orb->cmd->sense_buffer);
1380         } else {
1381                 /*
1382                  * If the orb completes with status == NULL, something
1383                  * went wrong, typically a bus reset happened mid-orb
1384                  * or when sending the write (less likely).
1385                  */
1386                 result = DID_BUS_BUSY << 16;
1387                 sbp2_conditionally_block(orb->lu);
1388         }
1389
1390         dma_unmap_single(device->card->device, orb->base.request_bus,
1391                          sizeof(orb->request), DMA_TO_DEVICE);
1392         sbp2_unmap_scatterlist(device->card->device, orb);
1393
1394         orb->cmd->result = result;
1395         orb->cmd->scsi_done(orb->cmd);
1396 }
1397
1398 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1399                 struct fw_device *device, struct sbp2_logical_unit *lu)
1400 {
1401         struct scatterlist *sg = scsi_sglist(orb->cmd);
1402         int i, n;
1403
1404         n = scsi_dma_map(orb->cmd);
1405         if (n <= 0)
1406                 goto fail;
1407
1408         /*
1409          * Handle the special case where there is only one element in
1410          * the scatter list by converting it to an immediate block
1411          * request. This is also a workaround for broken devices such
1412          * as the second generation iPod which doesn't support page
1413          * tables.
1414          */
1415         if (n == 1) {
1416                 orb->request.data_descriptor.high =
1417                         cpu_to_be32(lu->tgt->address_high);
1418                 orb->request.data_descriptor.low  =
1419                         cpu_to_be32(sg_dma_address(sg));
1420                 orb->request.misc |=
1421                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1422                 return 0;
1423         }
1424
1425         for_each_sg(sg, sg, n, i) {
1426                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1427                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1428         }
1429
1430         orb->page_table_bus =
1431                 dma_map_single(device->card->device, orb->page_table,
1432                                sizeof(orb->page_table), DMA_TO_DEVICE);
1433         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1434                 goto fail_page_table;
1435
1436         /*
1437          * The data_descriptor pointer is the one case where we need
1438          * to fill in the node ID part of the address.  All other
1439          * pointers assume that the data referenced reside on the
1440          * initiator (i.e. us), but data_descriptor can refer to data
1441          * on other nodes so we need to put our ID in descriptor.high.
1442          */
1443         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1444         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1445         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1446                                          COMMAND_ORB_DATA_SIZE(n));
1447
1448         return 0;
1449
1450  fail_page_table:
1451         scsi_dma_unmap(orb->cmd);
1452  fail:
1453         return -ENOMEM;
1454 }
1455
1456 /* SCSI stack integration */
1457
1458 static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1459                                   struct scsi_cmnd *cmd)
1460 {
1461         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1462         struct fw_device *device = target_parent_device(lu->tgt);
1463         struct sbp2_command_orb *orb;
1464         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1465
1466         /*
1467          * Bidirectional commands are not yet implemented, and unknown
1468          * transfer direction not handled.
1469          */
1470         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1471                 dev_err(lu_dev(lu), "cannot handle bidirectional command\n");
1472                 cmd->result = DID_ERROR << 16;
1473                 cmd->scsi_done(cmd);
1474                 return 0;
1475         }
1476
1477         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1478         if (orb == NULL) {
1479                 dev_notice(lu_dev(lu), "failed to alloc ORB\n");
1480                 return SCSI_MLQUEUE_HOST_BUSY;
1481         }
1482
1483         /* Initialize rcode to something not RCODE_COMPLETE. */
1484         orb->base.rcode = -1;
1485         kref_init(&orb->base.kref);
1486         orb->lu = lu;
1487         orb->cmd = cmd;
1488         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1489         orb->request.misc = cpu_to_be32(
1490                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1491                 COMMAND_ORB_SPEED(device->max_speed) |
1492                 COMMAND_ORB_NOTIFY);
1493
1494         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1495                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1496
1497         generation = device->generation;
1498         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1499
1500         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1501                 goto out;
1502
1503         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1504
1505         orb->base.callback = complete_command_orb;
1506         orb->base.request_bus =
1507                 dma_map_single(device->card->device, &orb->request,
1508                                sizeof(orb->request), DMA_TO_DEVICE);
1509         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1510                 sbp2_unmap_scatterlist(device->card->device, orb);
1511                 goto out;
1512         }
1513
1514         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1515                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1516         retval = 0;
1517  out:
1518         kref_put(&orb->base.kref, free_orb);
1519         return retval;
1520 }
1521
1522 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1523 {
1524         struct sbp2_logical_unit *lu = sdev->hostdata;
1525
1526         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1527         if (!lu)
1528                 return -ENOSYS;
1529
1530         sdev->allow_restart = 1;
1531
1532         /*
1533          * SBP-2 does not require any alignment, but we set it anyway
1534          * for compatibility with earlier versions of this driver.
1535          */
1536         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1537
1538         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1539                 sdev->inquiry_len = 36;
1540
1541         return 0;
1542 }
1543
1544 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1545 {
1546         struct sbp2_logical_unit *lu = sdev->hostdata;
1547
1548         sdev->use_10_for_rw = 1;
1549
1550         if (sbp2_param_exclusive_login)
1551                 sdev->manage_start_stop = 1;
1552
1553         if (sdev->type == TYPE_ROM)
1554                 sdev->use_10_for_ms = 1;
1555
1556         if (sdev->type == TYPE_DISK &&
1557             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1558                 sdev->skip_ms_page_8 = 1;
1559
1560         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1561                 sdev->fix_capacity = 1;
1562
1563         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1564                 sdev->start_stop_pwr_cond = 1;
1565
1566         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1567                 blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1568
1569         return 0;
1570 }
1571
1572 /*
1573  * Called by scsi stack when something has really gone wrong.  Usually
1574  * called when a command has timed-out for some reason.
1575  */
1576 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1577 {
1578         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1579
1580         dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1581         sbp2_agent_reset(lu);
1582         sbp2_cancel_orbs(lu);
1583
1584         return SUCCESS;
1585 }
1586
1587 /*
1588  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1589  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1590  *
1591  * This is the concatenation of target port identifier and logical unit
1592  * identifier as per SAM-2...SAM-4 annex A.
1593  */
1594 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1595                         struct device_attribute *attr, char *buf)
1596 {
1597         struct scsi_device *sdev = to_scsi_device(dev);
1598         struct sbp2_logical_unit *lu;
1599
1600         if (!sdev)
1601                 return 0;
1602
1603         lu = sdev->hostdata;
1604
1605         return sprintf(buf, "%016llx:%06x:%04x\n",
1606                         (unsigned long long)lu->tgt->guid,
1607                         lu->tgt->directory_id, lu->lun);
1608 }
1609
1610 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1611
1612 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1613         &dev_attr_ieee1394_id,
1614         NULL
1615 };
1616
1617 static struct scsi_host_template scsi_driver_template = {
1618         .module                 = THIS_MODULE,
1619         .name                   = "SBP-2 IEEE-1394",
1620         .proc_name              = "sbp2",
1621         .queuecommand           = sbp2_scsi_queuecommand,
1622         .slave_alloc            = sbp2_scsi_slave_alloc,
1623         .slave_configure        = sbp2_scsi_slave_configure,
1624         .eh_abort_handler       = sbp2_scsi_abort,
1625         .this_id                = -1,
1626         .sg_tablesize           = SG_ALL,
1627         .use_clustering         = ENABLE_CLUSTERING,
1628         .cmd_per_lun            = 1,
1629         .can_queue              = 1,
1630         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1631 };
1632
1633 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1634 MODULE_DESCRIPTION("SCSI over IEEE1394");
1635 MODULE_LICENSE("GPL");
1636 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1637
1638 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1639 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1640 MODULE_ALIAS("sbp2");
1641 #endif
1642
1643 static int __init sbp2_init(void)
1644 {
1645         return driver_register(&sbp2_driver.driver);
1646 }
1647
1648 static void __exit sbp2_cleanup(void)
1649 {
1650         driver_unregister(&sbp2_driver.driver);
1651 }
1652
1653 module_init(sbp2_init);
1654 module_exit(sbp2_cleanup);