drivers/firewire/fw-sbp2.c

   1 /*
   2  * SBP2 driver (SCSI over IEEE1394)
   3  *
   4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22  * The basic structure of this driver is based on the old storage driver,
  23  * drivers/ieee1394/sbp2.c, originally written by
  24  *     James Goodwin <jamesg@filanet.com>
  25  * with later contributions and ongoing maintenance from
  26  *     Ben Collins <bcollins@debian.org>,
  27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  28  * and many others.
  29  */
  30
  31 #include <linux/blkdev.h>
  32 #include <linux/bug.h>
  33 #include <linux/delay.h>
  34 #include <linux/device.h>
  35 #include <linux/dma-mapping.h>
  36 #include <linux/kernel.h>
  37 #include <linux/mod_devicetable.h>
  38 #include <linux/module.h>
  39 #include <linux/moduleparam.h>
  40 #include <linux/scatterlist.h>
  41 #include <linux/string.h>
  42 #include <linux/stringify.h>
  43 #include <linux/timer.h>
  44 #include <linux/workqueue.h>
  45 #include <asm/system.h>
  46
  47 #include <scsi/scsi.h>
  48 #include <scsi/scsi_cmnd.h>
  49 #include <scsi/scsi_device.h>
  50 #include <scsi/scsi_host.h>
  51
  52 #include "fw-device.h"
  53 #include "fw-topology.h"
  54 #include "fw-transaction.h"
  55
  56 /*
  57  * So far only bridges from Oxford Semiconductor are known to support
  58  * concurrent logins. Depending on firmware, four or two concurrent logins
  59  * are possible on OXFW911 and newer Oxsemi bridges.
  60  *
  61  * Concurrent logins are useful together with cluster filesystems.
  62  */
  63 static int sbp2_param_exclusive_login = 1;
  64 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  65 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  66                  "(default = Y, use N for concurrent initiators)");
  67
  68 /*
  69  * Flags for firmware oddities
  70  *
  71  * - 128kB max transfer
  72  *   Limit transfer size. Necessary for some old bridges.
  73  *
  74  * - 36 byte inquiry
  75  *   When scsi_mod probes the device, let the inquiry command look like that
  76  *   from MS Windows.
  77  *
  78  * - skip mode page 8
  79  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  80  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  81  *
  82  * - fix capacity
  83  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  84  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  85  *   Don't use this with devices which don't have this bug.
  86  *
  87  * - delay inquiry
  88  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  89  *
  90  * - power condition
  91  *   Set the power condition field in the START STOP UNIT commands sent by
  92  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  93  *   Some disks need this to spin down or to resume properly.
  94  *
  95  * - override internal blacklist
  96  *   Instead of adding to the built-in blacklist, use only the workarounds
  97  *   specified in the module load parameter.
  98  *   Useful if a blacklist entry interfered with a non-broken device.
  99  */
 100 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 101 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 102 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 103 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 104 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 105 #define SBP2_INQUIRY_DELAY              12
 106 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 107 #define SBP2_WORKAROUND_OVERRIDE        0x100
 108
 109 static int sbp2_param_workarounds;
 110 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 111 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 112         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 113         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 114         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 115         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 116         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 117         ", set power condition in start stop unit = "
 118                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 119         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 120         ", or a combination)");
 121
 122 /* I don't know why the SCSI stack doesn't define something like this... */
 123 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
 124
 125 static const char sbp2_driver_name[] = "sbp2";
 126
 127 /*
 128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 129  * and one struct scsi_device per sbp2_logical_unit.
 130  */
 131 struct sbp2_logical_unit {
 132         struct sbp2_target *tgt;
 133         struct list_head link;
 134         struct fw_address_handler address_handler;
 135         struct list_head orb_list;
 136
 137         u64 command_block_agent_address;
 138         u16 lun;
 139         int login_id;
 140
 141         /*
 142          * The generation is updated once we've logged in or reconnected
 143          * to the logical unit.  Thus, I/O to the device will automatically
 144          * fail and get retried if it happens in a window where the device
 145          * is not ready, e.g. after a bus reset but before we reconnect.
 146          */
 147         int generation;
 148         int retries;
 149         struct delayed_work work;
 150         bool has_sdev;
 151         bool blocked;
 152 };
 153
 154 /*
 155  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 156  * and one struct Scsi_Host per sbp2_target.
 157  */
 158 struct sbp2_target {
 159         struct kref kref;
 160         struct fw_unit *unit;
 161         const char *bus_id;
 162         struct list_head lu_list;
 163
 164         u64 management_agent_address;
 165         u64 guid;
 166         int directory_id;
 167         int node_id;
 168         int address_high;
 169         unsigned int workarounds;
 170         unsigned int mgt_orb_timeout;
 171         unsigned int max_payload;
 172
 173         int dont_block; /* counter for each logical unit */
 174         int blocked;    /* ditto */
 175 };
 176
 177 /* Impossible login_id, to detect logout attempt before successful login */
 178 #define INVALID_LOGIN_ID 0x10000
 179
 180 /*
 181  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
 182  * provided in the config rom. Most devices do provide a value, which
 183  * we'll use for login management orbs, but with some sane limits.
 184  */
 185 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
 186 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
 187 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
 188 #define SBP2_ORB_NULL                   0x80000000
 189 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 190 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 191
 192 /*
 193  * The default maximum s/g segment size of a FireWire controller is
 194  * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
 195  * be quadlet-aligned, we set the length limit to 0xffff & ~3.
 196  */
 197 #define SBP2_MAX_SEG_SIZE               0xfffc
 198
 199 /* Unit directory keys */
 200 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 201 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 202 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 203 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 204
 205 /* Management orb opcodes */
 206 #define SBP2_LOGIN_REQUEST              0x0
 207 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 208 #define SBP2_RECONNECT_REQUEST          0x3
 209 #define SBP2_SET_PASSWORD_REQUEST       0x4
 210 #define SBP2_LOGOUT_REQUEST             0x7
 211 #define SBP2_ABORT_TASK_REQUEST         0xb
 212 #define SBP2_ABORT_TASK_SET             0xc
 213 #define SBP2_LOGICAL_UNIT_RESET         0xe
 214 #define SBP2_TARGET_RESET_REQUEST       0xf
 215
 216 /* Offsets for command block agent registers */
 217 #define SBP2_AGENT_STATE                0x00
 218 #define SBP2_AGENT_RESET                0x04
 219 #define SBP2_ORB_POINTER                0x08
 220 #define SBP2_DOORBELL                   0x10
 221 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 222
 223 /* Status write response codes */
 224 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 225 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 226 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 227 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 228
 229 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 230 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 231 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 232 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 233 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 234 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 235 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 236 #define STATUS_GET_DATA(v)              ((v).data)
 237
 238 struct sbp2_status {
 239         u32 status;
 240         u32 orb_low;
 241         u8 data[24];
 242 };
 243
 244 struct sbp2_pointer {
 245         __be32 high;
 246         __be32 low;
 247 };
 248
 249 struct sbp2_orb {
 250         struct fw_transaction t;
 251         struct kref kref;
 252         dma_addr_t request_bus;
 253         int rcode;
 254         struct sbp2_pointer pointer;
 255         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 256         struct list_head link;
 257 };
 258
 259 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 260 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 261 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 262 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 263 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 264 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 265
 266 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 267 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 268
 269 struct sbp2_management_orb {
 270         struct sbp2_orb base;
 271         struct {
 272                 struct sbp2_pointer password;
 273                 struct sbp2_pointer response;
 274                 __be32 misc;
 275                 __be32 length;
 276                 struct sbp2_pointer status_fifo;
 277         } request;
 278         __be32 response[4];
 279         dma_addr_t response_bus;
 280         struct completion done;
 281         struct sbp2_status status;
 282 };
 283
 284 struct sbp2_login_response {
 285         __be32 misc;
 286         struct sbp2_pointer command_block_agent;
 287         __be32 reconnect_hold;
 288 };
 289 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 290 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 291 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 292 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 293 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 294 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 295 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 296 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 297
 298 struct sbp2_command_orb {
 299         struct sbp2_orb base;
 300         struct {
 301                 struct sbp2_pointer next;
 302                 struct sbp2_pointer data_descriptor;
 303                 __be32 misc;
 304                 u8 command_block[12];
 305         } request;
 306         struct scsi_cmnd *cmd;
 307         scsi_done_fn_t done;
 308         struct sbp2_logical_unit *lu;
 309
 310         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 311         dma_addr_t page_table_bus;
 312 };
 313
 314 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 315 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 316
 317 /*
 318  * List of devices with known bugs.
 319  *
 320  * The firmware_revision field, masked with 0xffff00, is the best
 321  * indicator for the type of bridge chip of a device.  It yields a few
 322  * false positives but this did not break correctly behaving devices
 323  * so far.
 324  */
 325 static const struct {
 326         u32 firmware_revision;
 327         u32 model;
 328         unsigned int workarounds;
 329 } sbp2_workarounds_table[] = {
 330         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 331                 .firmware_revision      = 0x002800,
 332                 .model                  = 0x001010,
 333                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 334                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 335                                           SBP2_WORKAROUND_POWER_CONDITION,
 336         },
 337         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 338                 .firmware_revision      = 0x002800,
 339                 .model                  = 0x000000,
 340                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
 341                                           SBP2_WORKAROUND_POWER_CONDITION,
 342         },
 343         /* Initio bridges, actually only needed for some older ones */ {
 344                 .firmware_revision      = 0x000200,
 345                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 346                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 347         },
 348         /* PL-3507 bridge with Prolific firmware */ {
 349                 .firmware_revision      = 0x012800,
 350                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 351                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 352         },
 353         /* Symbios bridge */ {
 354                 .firmware_revision      = 0xa0b800,
 355                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 356                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 357         },
 358         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 359                 .firmware_revision      = 0x002600,
 360                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 361                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 362         },
 363         /*
 364          * iPod 2nd generation: needs 128k max transfer size workaround
 365          * iPod 3rd generation: needs fix capacity workaround
 366          */
 367         {
 368                 .firmware_revision      = 0x0a2700,
 369                 .model                  = 0x000000,
 370                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 371                                           SBP2_WORKAROUND_FIX_CAPACITY,
 372         },
 373         /* iPod 4th generation */ {
 374                 .firmware_revision      = 0x0a2700,
 375                 .model                  = 0x000021,
 376                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 377         },
 378         /* iPod mini */ {
 379                 .firmware_revision      = 0x0a2700,
 380                 .model                  = 0x000022,
 381                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 382         },
 383         /* iPod mini */ {
 384                 .firmware_revision      = 0x0a2700,
 385                 .model                  = 0x000023,
 386                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 387         },
 388         /* iPod Photo */ {
 389                 .firmware_revision      = 0x0a2700,
 390                 .model                  = 0x00007e,
 391                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 392         }
 393 };
 394
 395 static void
 396 free_orb(struct kref *kref)
 397 {
 398         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 399
 400         kfree(orb);
 401 }
 402
 403 static void
 404 sbp2_status_write(struct fw_card *card, struct fw_request *request,
 405                   int tcode, int destination, int source,
 406                   int generation, int speed,
 407                   unsigned long long offset,
 408                   void *payload, size_t length, void *callback_data)
 409 {
 410         struct sbp2_logical_unit *lu = callback_data;
 411         struct sbp2_orb *orb;
 412         struct sbp2_status status;
 413         size_t header_size;
 414         unsigned long flags;
 415
 416         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 417             length == 0 || length > sizeof(status)) {
 418                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 419                 return;
 420         }
 421
 422         header_size = min(length, 2 * sizeof(u32));
 423         fw_memcpy_from_be32(&status, payload, header_size);
 424         if (length > header_size)
 425                 memcpy(status.data, payload + 8, length - header_size);
 426         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 427                 fw_notify("non-orb related status write, not handled\n");
 428                 fw_send_response(card, request, RCODE_COMPLETE);
 429                 return;
 430         }
 431
 432         /* Lookup the orb corresponding to this status write. */
 433         spin_lock_irqsave(&card->lock, flags);
 434         list_for_each_entry(orb, &lu->orb_list, link) {
 435                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 436                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 437                         orb->rcode = RCODE_COMPLETE;
 438                         list_del(&orb->link);
 439                         break;
 440                 }
 441         }
 442         spin_unlock_irqrestore(&card->lock, flags);
 443
 444         if (&orb->link != &lu->orb_list)
 445                 orb->callback(orb, &status);
 446         else
 447                 fw_error("status write for unknown orb\n");
 448
 449         kref_put(&orb->kref, free_orb);
 450
 451         fw_send_response(card, request, RCODE_COMPLETE);
 452 }
 453
 454 static void
 455 complete_transaction(struct fw_card *card, int rcode,
 456                      void *payload, size_t length, void *data)
 457 {
 458         struct sbp2_orb *orb = data;
 459         unsigned long flags;
 460
 461         /*
 462          * This is a little tricky.  We can get the status write for
 463          * the orb before we get this callback.  The status write
 464          * handler above will assume the orb pointer transaction was
 465          * successful and set the rcode to RCODE_COMPLETE for the orb.
 466          * So this callback only sets the rcode if it hasn't already
 467          * been set and only does the cleanup if the transaction
 468          * failed and we didn't already get a status write.
 469          */
 470         spin_lock_irqsave(&card->lock, flags);
 471
 472         if (orb->rcode == -1)
 473                 orb->rcode = rcode;
 474         if (orb->rcode != RCODE_COMPLETE) {
 475                 list_del(&orb->link);
 476                 spin_unlock_irqrestore(&card->lock, flags);
 477                 orb->callback(orb, NULL);
 478         } else {
 479                 spin_unlock_irqrestore(&card->lock, flags);
 480         }
 481
 482         kref_put(&orb->kref, free_orb);
 483 }
 484
 485 static void
 486 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 487               int node_id, int generation, u64 offset)
 488 {
 489         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 490         unsigned long flags;
 491
 492         orb->pointer.high = 0;
 493         orb->pointer.low = cpu_to_be32(orb->request_bus);
 494
 495         spin_lock_irqsave(&device->card->lock, flags);
 496         list_add_tail(&orb->link, &lu->orb_list);
 497         spin_unlock_irqrestore(&device->card->lock, flags);
 498
 499         /* Take a ref for the orb list and for the transaction callback. */
 500         kref_get(&orb->kref);
 501         kref_get(&orb->kref);
 502
 503         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 504                         node_id, generation, device->max_speed, offset,
 505                         &orb->pointer, sizeof(orb->pointer),
 506                         complete_transaction, orb);
 507 }
 508
 509 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 510 {
 511         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 512         struct sbp2_orb *orb, *next;
 513         struct list_head list;
 514         unsigned long flags;
 515         int retval = -ENOENT;
 516
 517         INIT_LIST_HEAD(&list);
 518         spin_lock_irqsave(&device->card->lock, flags);
 519         list_splice_init(&lu->orb_list, &list);
 520         spin_unlock_irqrestore(&device->card->lock, flags);
 521
 522         list_for_each_entry_safe(orb, next, &list, link) {
 523                 retval = 0;
 524                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 525                         continue;
 526
 527                 orb->rcode = RCODE_CANCELLED;
 528                 orb->callback(orb, NULL);
 529         }
 530
 531         return retval;
 532 }
 533
 534 static void
 535 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 536 {
 537         struct sbp2_management_orb *orb =
 538                 container_of(base_orb, struct sbp2_management_orb, base);
 539
 540         if (status)
 541                 memcpy(&orb->status, status, sizeof(*status));
 542         complete(&orb->done);
 543 }
 544
 545 static int
 546 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 547                          int generation, int function, int lun_or_login_id,
 548                          void *response)
 549 {
 550         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 551         struct sbp2_management_orb *orb;
 552         unsigned int timeout;
 553         int retval = -ENOMEM;
 554
 555         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 556                 return 0;
 557
 558         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 559         if (orb == NULL)
 560                 return -ENOMEM;
 561
 562         kref_init(&orb->base.kref);
 563         orb->response_bus =
 564                 dma_map_single(device->card->device, &orb->response,
 565                                sizeof(orb->response), DMA_FROM_DEVICE);
 566         if (dma_mapping_error(device->card->device, orb->response_bus))
 567                 goto fail_mapping_response;
 568
 569         orb->request.response.high = 0;
 570         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 571
 572         orb->request.misc = cpu_to_be32(
 573                 MANAGEMENT_ORB_NOTIFY |
 574                 MANAGEMENT_ORB_FUNCTION(function) |
 575                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 576         orb->request.length = cpu_to_be32(
 577                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 578
 579         orb->request.status_fifo.high =
 580                 cpu_to_be32(lu->address_handler.offset >> 32);
 581         orb->request.status_fifo.low  =
 582                 cpu_to_be32(lu->address_handler.offset);
 583
 584         if (function == SBP2_LOGIN_REQUEST) {
 585                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 586                 orb->request.misc |= cpu_to_be32(
 587                         MANAGEMENT_ORB_RECONNECT(2) |
 588                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 589                 timeout = lu->tgt->mgt_orb_timeout;
 590         } else {
 591                 timeout = SBP2_ORB_TIMEOUT;
 592         }
 593
 594         init_completion(&orb->done);
 595         orb->base.callback = complete_management_orb;
 596
 597         orb->base.request_bus =
 598                 dma_map_single(device->card->device, &orb->request,
 599                                sizeof(orb->request), DMA_TO_DEVICE);
 600         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 601                 goto fail_mapping_request;
 602
 603         sbp2_send_orb(&orb->base, lu, node_id, generation,
 604                       lu->tgt->management_agent_address);
 605
 606         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 607
 608         retval = -EIO;
 609         if (sbp2_cancel_orbs(lu) == 0) {
 610                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 611                          lu->tgt->bus_id, orb->base.rcode);
 612                 goto out;
 613         }
 614
 615         if (orb->base.rcode != RCODE_COMPLETE) {
 616                 fw_error("%s: management write failed, rcode 0x%02x\n",
 617                          lu->tgt->bus_id, orb->base.rcode);
 618                 goto out;
 619         }
 620
 621         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 622             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 623                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 624                          STATUS_GET_RESPONSE(orb->status),
 625                          STATUS_GET_SBP_STATUS(orb->status));
 626                 goto out;
 627         }
 628
 629         retval = 0;
 630  out:
 631         dma_unmap_single(device->card->device, orb->base.request_bus,
 632                          sizeof(orb->request), DMA_TO_DEVICE);
 633  fail_mapping_request:
 634         dma_unmap_single(device->card->device, orb->response_bus,
 635                          sizeof(orb->response), DMA_FROM_DEVICE);
 636  fail_mapping_response:
 637         if (response)
 638                 memcpy(response, orb->response, sizeof(orb->response));
 639         kref_put(&orb->base.kref, free_orb);
 640
 641         return retval;
 642 }
 643
 644 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 645 {
 646         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 647         __be32 d = 0;
 648
 649         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 650                            lu->tgt->node_id, lu->generation, device->max_speed,
 651                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 652                            &d, sizeof(d));
 653 }
 654
 655 static void
 656 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 657                                    void *payload, size_t length, void *data)
 658 {
 659         kfree(data);
 660 }
 661
 662 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 663 {
 664         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 665         struct fw_transaction *t;
 666         static __be32 d;
 667
 668         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 669         if (t == NULL)
 670                 return;
 671
 672         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 673                         lu->tgt->node_id, lu->generation, device->max_speed,
 674                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 675                         &d, sizeof(d), complete_agent_reset_write_no_wait, t);
 676 }
 677
 678 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 679 {
 680         /*
 681          * We may access dont_block without taking card->lock here:
 682          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 683          * are currently serialized against each other.
 684          * And a wrong result in sbp2_conditionally_block()'s access of
 685          * dont_block is rather harmless, it simply misses its first chance.
 686          */
 687         --lu->tgt->dont_block;
 688 }
 689
 690 /*
 691  * Blocks lu->tgt if all of the following conditions are met:
 692  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 693  *     logical units have been finished (indicated by dont_block == 0).
 694  *   - lu->generation is stale.
 695  *
 696  * Note, scsi_block_requests() must be called while holding card->lock,
 697  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 698  * unblock the target.
 699  */
 700 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 701 {
 702         struct sbp2_target *tgt = lu->tgt;
 703         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 704         struct Scsi_Host *shost =
 705                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 706         unsigned long flags;
 707
 708         spin_lock_irqsave(&card->lock, flags);
 709         if (!tgt->dont_block && !lu->blocked &&
 710             lu->generation != card->generation) {
 711                 lu->blocked = true;
 712                 if (++tgt->blocked == 1)
 713                         scsi_block_requests(shost);
 714         }
 715         spin_unlock_irqrestore(&card->lock, flags);
 716 }
 717
 718 /*
 719  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 720  * Note, it is harmless to run scsi_unblock_requests() outside the
 721  * card->lock protected section.  On the other hand, running it inside
 722  * the section might clash with shost->host_lock.
 723  */
 724 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 725 {
 726         struct sbp2_target *tgt = lu->tgt;
 727         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 728         struct Scsi_Host *shost =
 729                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 730         unsigned long flags;
 731         bool unblock = false;
 732
 733         spin_lock_irqsave(&card->lock, flags);
 734         if (lu->blocked && lu->generation == card->generation) {
 735                 lu->blocked = false;
 736                 unblock = --tgt->blocked == 0;
 737         }
 738         spin_unlock_irqrestore(&card->lock, flags);
 739
 740         if (unblock)
 741                 scsi_unblock_requests(shost);
 742 }
 743
 744 /*
 745  * Prevents future blocking of tgt and unblocks it.
 746  * Note, it is harmless to run scsi_unblock_requests() outside the
 747  * card->lock protected section.  On the other hand, running it inside
 748  * the section might clash with shost->host_lock.
 749  */
 750 static void sbp2_unblock(struct sbp2_target *tgt)
 751 {
 752         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 753         struct Scsi_Host *shost =
 754                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 755         unsigned long flags;
 756
 757         spin_lock_irqsave(&card->lock, flags);
 758         ++tgt->dont_block;
 759         spin_unlock_irqrestore(&card->lock, flags);
 760
 761         scsi_unblock_requests(shost);
 762 }
 763
 764 static int sbp2_lun2int(u16 lun)
 765 {
 766         struct scsi_lun eight_bytes_lun;
 767
 768         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 769         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 770         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 771
 772         return scsilun_to_int(&eight_bytes_lun);
 773 }
 774
 775 static void sbp2_release_target(struct kref *kref)
 776 {
 777         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 778         struct sbp2_logical_unit *lu, *next;
 779         struct Scsi_Host *shost =
 780                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 781         struct scsi_device *sdev;
 782         struct fw_device *device = fw_device(tgt->unit->device.parent);
 783
 784         /* prevent deadlocks */
 785         sbp2_unblock(tgt);
 786
 787         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 788                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 789                 if (sdev) {
 790                         scsi_remove_device(sdev);
 791                         scsi_device_put(sdev);
 792                 }
 793                 if (lu->login_id != INVALID_LOGIN_ID) {
 794                         int generation, node_id;
 795                         /*
 796                          * tgt->node_id may be obsolete here if we failed
 797                          * during initial login or after a bus reset where
 798                          * the topology changed.
 799                          */
 800                         generation = device->generation;
 801                         smp_rmb(); /* node_id vs. generation */
 802                         node_id    = device->node_id;
 803                         sbp2_send_management_orb(lu, node_id, generation,
 804                                                  SBP2_LOGOUT_REQUEST,
 805                                                  lu->login_id, NULL);
 806                 }
 807                 fw_core_remove_address_handler(&lu->address_handler);
 808                 list_del(&lu->link);
 809                 kfree(lu);
 810         }
 811         scsi_remove_host(shost);
 812         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
 813
 814         fw_unit_put(tgt->unit);
 815         scsi_host_put(shost);
 816         fw_device_put(device);
 817 }
 818
 819 static struct workqueue_struct *sbp2_wq;
 820
 821 static void sbp2_target_put(struct sbp2_target *tgt)
 822 {
 823         kref_put(&tgt->kref, sbp2_release_target);
 824 }
 825
 826 /*
 827  * Always get the target's kref when scheduling work on one its units.
 828  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 829  */
 830 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 831 {
 832         kref_get(&lu->tgt->kref);
 833         if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
 834                 sbp2_target_put(lu->tgt);
 835 }
 836
 837 /*
 838  * Write retransmit retry values into the BUSY_TIMEOUT register.
 839  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 840  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 841  *   saner value after logging into the device.
 842  * - The dual-phase retry protocol is optional to implement, and if not
 843  *   supported, writes to the dual-phase portion of the register will be
 844  *   ignored. We try to write the original 1394-1995 default here.
 845  * - In the case of devices that are also SBP-3-compliant, all writes are
 846  *   ignored, as the register is read-only, but contains single-phase retry of
 847  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 848  *   write attempt is safe and yields more consistent behavior for all devices.
 849  *
 850  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 851  * and section 6.4 of the SBP-3 spec for further details.
 852  */
 853 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 854 {
 855         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 856         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 857
 858         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 859                            lu->tgt->node_id, lu->generation, device->max_speed,
 860                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
 861                            &d, sizeof(d));
 862 }
 863
 864 static void sbp2_reconnect(struct work_struct *work);
 865
 866 static void sbp2_login(struct work_struct *work)
 867 {
 868         struct sbp2_logical_unit *lu =
 869                 container_of(work, struct sbp2_logical_unit, work.work);
 870         struct sbp2_target *tgt = lu->tgt;
 871         struct fw_device *device = fw_device(tgt->unit->device.parent);
 872         struct Scsi_Host *shost;
 873         struct scsi_device *sdev;
 874         struct sbp2_login_response response;
 875         int generation, node_id, local_node_id;
 876
 877         if (fw_device_is_shutdown(device))
 878                 goto out;
 879
 880         generation    = device->generation;
 881         smp_rmb();    /* node IDs must not be older than generation */
 882         node_id       = device->node_id;
 883         local_node_id = device->card->node_id;
 884
 885         /* If this is a re-login attempt, log out, or we might be rejected. */
 886         if (lu->has_sdev)
 887                 sbp2_send_management_orb(lu, device->node_id, generation,
 888                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 889
 890         if (sbp2_send_management_orb(lu, node_id, generation,
 891                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 892                 if (lu->retries++ < 5) {
 893                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 894                 } else {
 895                         fw_error("%s: failed to login to LUN %04x\n",
 896                                  tgt->bus_id, lu->lun);
 897                         /* Let any waiting I/O fail from now on. */
 898                         sbp2_unblock(lu->tgt);
 899                 }
 900                 goto out;
 901         }
 902
 903         tgt->node_id      = node_id;
 904         tgt->address_high = local_node_id << 16;
 905         smp_wmb();        /* node IDs must not be older than generation */
 906         lu->generation    = generation;
 907
 908         lu->command_block_agent_address =
 909                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 910                       << 32) | be32_to_cpu(response.command_block_agent.low);
 911         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 912
 913         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 914                   tgt->bus_id, lu->lun, lu->retries);
 915
 916         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 917         sbp2_set_busy_timeout(lu);
 918
 919         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 920         sbp2_agent_reset(lu);
 921
 922         /* This was a re-login. */
 923         if (lu->has_sdev) {
 924                 sbp2_cancel_orbs(lu);
 925                 sbp2_conditionally_unblock(lu);
 926                 goto out;
 927         }
 928
 929         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 930                 ssleep(SBP2_INQUIRY_DELAY);
 931
 932         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 933         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 934         /*
 935          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 936          * Therefore __scsi_add_device() will get into trouble if a bus reset
 937          * happens in parallel.  It will either fail or leave us with an
 938          * unusable sdev.  As a workaround we check for this and retry the
 939          * whole login and SCSI probing.
 940          */
 941
 942         /* Reported error during __scsi_add_device() */
 943         if (IS_ERR(sdev))
 944                 goto out_logout_login;
 945
 946         /* Unreported error during __scsi_add_device() */
 947         smp_rmb(); /* get current card generation */
 948         if (generation != device->card->generation) {
 949                 scsi_remove_device(sdev);
 950                 scsi_device_put(sdev);
 951                 goto out_logout_login;
 952         }
 953
 954         /* No error during __scsi_add_device() */
 955         lu->has_sdev = true;
 956         scsi_device_put(sdev);
 957         sbp2_allow_block(lu);
 958         goto out;
 959
 960  out_logout_login:
 961         smp_rmb(); /* generation may have changed */
 962         generation = device->generation;
 963         smp_rmb(); /* node_id must not be older than generation */
 964
 965         sbp2_send_management_orb(lu, device->node_id, generation,
 966                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 967         /*
 968          * If a bus reset happened, sbp2_update will have requeued
 969          * lu->work already.  Reset the work from reconnect to login.
 970          */
 971         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 972  out:
 973         sbp2_target_put(tgt);
 974 }
 975
 976 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 977 {
 978         struct sbp2_logical_unit *lu;
 979
 980         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 981         if (!lu)
 982                 return -ENOMEM;
 983
 984         lu->address_handler.length           = 0x100;
 985         lu->address_handler.address_callback = sbp2_status_write;
 986         lu->address_handler.callback_data    = lu;
 987
 988         if (fw_core_add_address_handler(&lu->address_handler,
 989                                         &fw_high_memory_region) < 0) {
 990                 kfree(lu);
 991                 return -ENOMEM;
 992         }
 993
 994         lu->tgt      = tgt;
 995         lu->lun      = lun_entry & 0xffff;
 996         lu->login_id = INVALID_LOGIN_ID;
 997         lu->retries  = 0;
 998         lu->has_sdev = false;
 999         lu->blocked  = false;
1000         ++tgt->dont_block;
1001         INIT_LIST_HEAD(&lu->orb_list);
1002         INIT_DELAYED_WORK(&lu->work, sbp2_login);
1003
1004         list_add_tail(&lu->link, &tgt->lu_list);
1005         return 0;
1006 }
1007
1008 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
1009 {
1010         struct fw_csr_iterator ci;
1011         int key, value;
1012
1013         fw_csr_iterator_init(&ci, directory);
1014         while (fw_csr_iterator_next(&ci, &key, &value))
1015                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1016                     sbp2_add_logical_unit(tgt, value) < 0)
1017                         return -ENOMEM;
1018         return 0;
1019 }
1020
1021 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
1022                               u32 *model, u32 *firmware_revision)
1023 {
1024         struct fw_csr_iterator ci;
1025         int key, value;
1026         unsigned int timeout;
1027
1028         fw_csr_iterator_init(&ci, directory);
1029         while (fw_csr_iterator_next(&ci, &key, &value)) {
1030                 switch (key) {
1031
1032                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1033                         tgt->management_agent_address =
1034                                         CSR_REGISTER_BASE + 4 * value;
1035                         break;
1036
1037                 case CSR_DIRECTORY_ID:
1038                         tgt->directory_id = value;
1039                         break;
1040
1041                 case CSR_MODEL:
1042                         *model = value;
1043                         break;
1044
1045                 case SBP2_CSR_FIRMWARE_REVISION:
1046                         *firmware_revision = value;
1047                         break;
1048
1049                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1050                         /* the timeout value is stored in 500ms units */
1051                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1052                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1053                         tgt->mgt_orb_timeout =
1054                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1055
1056                         if (timeout > tgt->mgt_orb_timeout)
1057                                 fw_notify("%s: config rom contains %ds "
1058                                           "management ORB timeout, limiting "
1059                                           "to %ds\n", tgt->bus_id,
1060                                           timeout / 1000,
1061                                           tgt->mgt_orb_timeout / 1000);
1062                         break;
1063
1064                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1065                         if (sbp2_add_logical_unit(tgt, value) < 0)
1066                                 return -ENOMEM;
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 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1080                                   u32 firmware_revision)
1081 {
1082         int i;
1083         unsigned int w = sbp2_param_workarounds;
1084
1085         if (w)
1086                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1087                           "if you need the workarounds parameter for %s\n",
1088                           tgt->bus_id);
1089
1090         if (w & SBP2_WORKAROUND_OVERRIDE)
1091                 goto out;
1092
1093         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1094
1095                 if (sbp2_workarounds_table[i].firmware_revision !=
1096                     (firmware_revision & 0xffffff00))
1097                         continue;
1098
1099                 if (sbp2_workarounds_table[i].model != model &&
1100                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1101                         continue;
1102
1103                 w |= sbp2_workarounds_table[i].workarounds;
1104                 break;
1105         }
1106  out:
1107         if (w)
1108                 fw_notify("Workarounds for %s: 0x%x "
1109                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1110                           tgt->bus_id, w, firmware_revision, model);
1111         tgt->workarounds = w;
1112 }
1113
1114 static struct scsi_host_template scsi_driver_template;
1115
1116 static int sbp2_probe(struct device *dev)
1117 {
1118         struct fw_unit *unit = fw_unit(dev);
1119         struct fw_device *device = fw_device(unit->device.parent);
1120         struct sbp2_target *tgt;
1121         struct sbp2_logical_unit *lu;
1122         struct Scsi_Host *shost;
1123         u32 model, firmware_revision;
1124
1125         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1126                 BUG_ON(dma_set_max_seg_size(device->card->device,
1127                                             SBP2_MAX_SEG_SIZE));
1128
1129         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1130         if (shost == NULL)
1131                 return -ENOMEM;
1132
1133         tgt = (struct sbp2_target *)shost->hostdata;
1134         unit->device.driver_data = tgt;
1135         tgt->unit = unit;
1136         kref_init(&tgt->kref);
1137         INIT_LIST_HEAD(&tgt->lu_list);
1138         tgt->bus_id = dev_name(&unit->device);
1139         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1140
1141         if (fw_device_enable_phys_dma(device) < 0)
1142                 goto fail_shost_put;
1143
1144         if (scsi_add_host(shost, &unit->device) < 0)
1145                 goto fail_shost_put;
1146
1147         fw_device_get(device);
1148         fw_unit_get(unit);
1149
1150         /* implicit directory ID */
1151         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1152                              + CSR_CONFIG_ROM) & 0xffffff;
1153
1154         firmware_revision = SBP2_ROM_VALUE_MISSING;
1155         model             = SBP2_ROM_VALUE_MISSING;
1156
1157         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1158                                &firmware_revision) < 0)
1159                 goto fail_tgt_put;
1160
1161         sbp2_init_workarounds(tgt, model, firmware_revision);
1162
1163         /*
1164          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1165          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1166          * specifies the max payload size as 2 ^ (max_payload + 2), so
1167          * if we set this to max_speed + 7, we get the right value.
1168          */
1169         tgt->max_payload = min(device->max_speed + 7, 10U);
1170         tgt->max_payload = min(tgt->max_payload, device->card->max_receive - 1);
1171
1172         /* Do the login in a workqueue so we can easily reschedule retries. */
1173         list_for_each_entry(lu, &tgt->lu_list, link)
1174                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1175         return 0;
1176
1177  fail_tgt_put:
1178         sbp2_target_put(tgt);
1179         return -ENOMEM;
1180
1181  fail_shost_put:
1182         scsi_host_put(shost);
1183         return -ENOMEM;
1184 }
1185
1186 static int sbp2_remove(struct device *dev)
1187 {
1188         struct fw_unit *unit = fw_unit(dev);
1189         struct sbp2_target *tgt = unit->device.driver_data;
1190
1191         sbp2_target_put(tgt);
1192         return 0;
1193 }
1194
1195 static void sbp2_reconnect(struct work_struct *work)
1196 {
1197         struct sbp2_logical_unit *lu =
1198                 container_of(work, struct sbp2_logical_unit, work.work);
1199         struct sbp2_target *tgt = lu->tgt;
1200         struct fw_device *device = fw_device(tgt->unit->device.parent);
1201         int generation, node_id, local_node_id;
1202
1203         if (fw_device_is_shutdown(device))
1204                 goto out;
1205
1206         generation    = device->generation;
1207         smp_rmb();    /* node IDs must not be older than generation */
1208         node_id       = device->node_id;
1209         local_node_id = device->card->node_id;
1210
1211         if (sbp2_send_management_orb(lu, node_id, generation,
1212                                      SBP2_RECONNECT_REQUEST,
1213                                      lu->login_id, NULL) < 0) {
1214                 /*
1215                  * If reconnect was impossible even though we are in the
1216                  * current generation, fall back and try to log in again.
1217                  *
1218                  * We could check for "Function rejected" status, but
1219                  * looking at the bus generation as simpler and more general.
1220                  */
1221                 smp_rmb(); /* get current card generation */
1222                 if (generation == device->card->generation ||
1223                     lu->retries++ >= 5) {
1224                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1225                         lu->retries = 0;
1226                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1227                 }
1228                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1229                 goto out;
1230         }
1231
1232         tgt->node_id      = node_id;
1233         tgt->address_high = local_node_id << 16;
1234         smp_wmb();        /* node IDs must not be older than generation */
1235         lu->generation    = generation;
1236
1237         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1238                   tgt->bus_id, lu->lun, lu->retries);
1239
1240         sbp2_agent_reset(lu);
1241         sbp2_cancel_orbs(lu);
1242         sbp2_conditionally_unblock(lu);
1243  out:
1244         sbp2_target_put(tgt);
1245 }
1246
1247 static void sbp2_update(struct fw_unit *unit)
1248 {
1249         struct sbp2_target *tgt = unit->device.driver_data;
1250         struct sbp2_logical_unit *lu;
1251
1252         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1253
1254         /*
1255          * Fw-core serializes sbp2_update() against sbp2_remove().
1256          * Iteration over tgt->lu_list is therefore safe here.
1257          */
1258         list_for_each_entry(lu, &tgt->lu_list, link) {
1259                 sbp2_conditionally_block(lu);
1260                 lu->retries = 0;
1261                 sbp2_queue_work(lu, 0);
1262         }
1263 }
1264
1265 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1266 #define SBP2_SW_VERSION_ENTRY   0x00010483
1267
1268 static const struct fw_device_id sbp2_id_table[] = {
1269         {
1270                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1271                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1272                 .version      = SBP2_SW_VERSION_ENTRY,
1273         },
1274         { }
1275 };
1276
1277 static struct fw_driver sbp2_driver = {
1278         .driver   = {
1279                 .owner  = THIS_MODULE,
1280                 .name   = sbp2_driver_name,
1281                 .bus    = &fw_bus_type,
1282                 .probe  = sbp2_probe,
1283                 .remove = sbp2_remove,
1284         },
1285         .update   = sbp2_update,
1286         .id_table = sbp2_id_table,
1287 };
1288
1289 static void sbp2_unmap_scatterlist(struct device *card_device,
1290                                    struct sbp2_command_orb *orb)
1291 {
1292         if (scsi_sg_count(orb->cmd))
1293                 dma_unmap_sg(card_device, scsi_sglist(orb->cmd),
1294                              scsi_sg_count(orb->cmd),
1295                              orb->cmd->sc_data_direction);
1296
1297         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1298                 dma_unmap_single(card_device, orb->page_table_bus,
1299                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1300 }
1301
1302 static unsigned int
1303 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1304 {
1305         int sam_status;
1306
1307         sense_data[0] = 0x70;
1308         sense_data[1] = 0x0;
1309         sense_data[2] = sbp2_status[1];
1310         sense_data[3] = sbp2_status[4];
1311         sense_data[4] = sbp2_status[5];
1312         sense_data[5] = sbp2_status[6];
1313         sense_data[6] = sbp2_status[7];
1314         sense_data[7] = 10;
1315         sense_data[8] = sbp2_status[8];
1316         sense_data[9] = sbp2_status[9];
1317         sense_data[10] = sbp2_status[10];
1318         sense_data[11] = sbp2_status[11];
1319         sense_data[12] = sbp2_status[2];
1320         sense_data[13] = sbp2_status[3];
1321         sense_data[14] = sbp2_status[12];
1322         sense_data[15] = sbp2_status[13];
1323
1324         sam_status = sbp2_status[0] & 0x3f;
1325
1326         switch (sam_status) {
1327         case SAM_STAT_GOOD:
1328         case SAM_STAT_CHECK_CONDITION:
1329         case SAM_STAT_CONDITION_MET:
1330         case SAM_STAT_BUSY:
1331         case SAM_STAT_RESERVATION_CONFLICT:
1332         case SAM_STAT_COMMAND_TERMINATED:
1333                 return DID_OK << 16 | sam_status;
1334
1335         default:
1336                 return DID_ERROR << 16;
1337         }
1338 }
1339
1340 static void
1341 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1342 {
1343         struct sbp2_command_orb *orb =
1344                 container_of(base_orb, struct sbp2_command_orb, base);
1345         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1346         int result;
1347
1348         if (status != NULL) {
1349                 if (STATUS_GET_DEAD(*status))
1350                         sbp2_agent_reset_no_wait(orb->lu);
1351
1352                 switch (STATUS_GET_RESPONSE(*status)) {
1353                 case SBP2_STATUS_REQUEST_COMPLETE:
1354                         result = DID_OK << 16;
1355                         break;
1356                 case SBP2_STATUS_TRANSPORT_FAILURE:
1357                         result = DID_BUS_BUSY << 16;
1358                         break;
1359                 case SBP2_STATUS_ILLEGAL_REQUEST:
1360                 case SBP2_STATUS_VENDOR_DEPENDENT:
1361                 default:
1362                         result = DID_ERROR << 16;
1363                         break;
1364                 }
1365
1366                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1367                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1368                                                            orb->cmd->sense_buffer);
1369         } else {
1370                 /*
1371                  * If the orb completes with status == NULL, something
1372                  * went wrong, typically a bus reset happened mid-orb
1373                  * or when sending the write (less likely).
1374                  */
1375                 result = DID_BUS_BUSY << 16;
1376                 sbp2_conditionally_block(orb->lu);
1377         }
1378
1379         dma_unmap_single(device->card->device, orb->base.request_bus,
1380                          sizeof(orb->request), DMA_TO_DEVICE);
1381         sbp2_unmap_scatterlist(device->card->device, orb);
1382
1383         orb->cmd->result = result;
1384         orb->done(orb->cmd);
1385 }
1386
1387 static int
1388 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1389                      struct sbp2_logical_unit *lu)
1390 {
1391         struct scatterlist *sg = scsi_sglist(orb->cmd);
1392         int i, n;
1393
1394         n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1395                        orb->cmd->sc_data_direction);
1396         if (n == 0)
1397                 goto fail;
1398
1399         /*
1400          * Handle the special case where there is only one element in
1401          * the scatter list by converting it to an immediate block
1402          * request. This is also a workaround for broken devices such
1403          * as the second generation iPod which doesn't support page
1404          * tables.
1405          */
1406         if (n == 1) {
1407                 orb->request.data_descriptor.high =
1408                         cpu_to_be32(lu->tgt->address_high);
1409                 orb->request.data_descriptor.low  =
1410                         cpu_to_be32(sg_dma_address(sg));
1411                 orb->request.misc |=
1412                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1413                 return 0;
1414         }
1415
1416         for_each_sg(sg, sg, n, i) {
1417                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1418                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1419         }
1420
1421         orb->page_table_bus =
1422                 dma_map_single(device->card->device, orb->page_table,
1423                                sizeof(orb->page_table), DMA_TO_DEVICE);
1424         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1425                 goto fail_page_table;
1426
1427         /*
1428          * The data_descriptor pointer is the one case where we need
1429          * to fill in the node ID part of the address.  All other
1430          * pointers assume that the data referenced reside on the
1431          * initiator (i.e. us), but data_descriptor can refer to data
1432          * on other nodes so we need to put our ID in descriptor.high.
1433          */
1434         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1435         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1436         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1437                                          COMMAND_ORB_DATA_SIZE(n));
1438
1439         return 0;
1440
1441  fail_page_table:
1442         dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1443                      scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
1444  fail:
1445         return -ENOMEM;
1446 }
1447
1448 /* SCSI stack integration */
1449
1450 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1451 {
1452         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1453         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1454         struct sbp2_command_orb *orb;
1455         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1456
1457         /*
1458          * Bidirectional commands are not yet implemented, and unknown
1459          * transfer direction not handled.
1460          */
1461         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1462                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1463                 cmd->result = DID_ERROR << 16;
1464                 done(cmd);
1465                 return 0;
1466         }
1467
1468         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1469         if (orb == NULL) {
1470                 fw_notify("failed to alloc orb\n");
1471                 return SCSI_MLQUEUE_HOST_BUSY;
1472         }
1473
1474         /* Initialize rcode to something not RCODE_COMPLETE. */
1475         orb->base.rcode = -1;
1476         kref_init(&orb->base.kref);
1477
1478         orb->lu   = lu;
1479         orb->done = done;
1480         orb->cmd  = cmd;
1481
1482         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1483         orb->request.misc = cpu_to_be32(
1484                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1485                 COMMAND_ORB_SPEED(device->max_speed) |
1486                 COMMAND_ORB_NOTIFY);
1487
1488         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1489                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1490
1491         generation = device->generation;
1492         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1493
1494         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1495                 goto out;
1496
1497         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1498
1499         orb->base.callback = complete_command_orb;
1500         orb->base.request_bus =
1501                 dma_map_single(device->card->device, &orb->request,
1502                                sizeof(orb->request), DMA_TO_DEVICE);
1503         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1504                 sbp2_unmap_scatterlist(device->card->device, orb);
1505                 goto out;
1506         }
1507
1508         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1509                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1510         retval = 0;
1511  out:
1512         kref_put(&orb->base.kref, free_orb);
1513         return retval;
1514 }
1515
1516 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1517 {
1518         struct sbp2_logical_unit *lu = sdev->hostdata;
1519
1520         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1521         if (!lu)
1522                 return -ENOSYS;
1523
1524         sdev->allow_restart = 1;
1525
1526         /* SBP-2 requires quadlet alignment of the data buffers. */
1527         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1528
1529         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1530                 sdev->inquiry_len = 36;
1531
1532         return 0;
1533 }
1534
1535 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1536 {
1537         struct sbp2_logical_unit *lu = sdev->hostdata;
1538
1539         sdev->use_10_for_rw = 1;
1540
1541         if (sbp2_param_exclusive_login)
1542                 sdev->manage_start_stop = 1;
1543
1544         if (sdev->type == TYPE_ROM)
1545                 sdev->use_10_for_ms = 1;
1546
1547         if (sdev->type == TYPE_DISK &&
1548             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1549                 sdev->skip_ms_page_8 = 1;
1550
1551         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1552                 sdev->fix_capacity = 1;
1553
1554         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1555                 sdev->start_stop_pwr_cond = 1;
1556
1557         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1558                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1559
1560         blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
1561
1562         return 0;
1563 }
1564
1565 /*
1566  * Called by scsi stack when something has really gone wrong.  Usually
1567  * called when a command has timed-out for some reason.
1568  */
1569 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1570 {
1571         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1572
1573         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1574         sbp2_agent_reset(lu);
1575         sbp2_cancel_orbs(lu);
1576
1577         return SUCCESS;
1578 }
1579
1580 /*
1581  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1582  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1583  *
1584  * This is the concatenation of target port identifier and logical unit
1585  * identifier as per SAM-2...SAM-4 annex A.
1586  */
1587 static ssize_t
1588 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1589                             char *buf)
1590 {
1591         struct scsi_device *sdev = to_scsi_device(dev);
1592         struct sbp2_logical_unit *lu;
1593
1594         if (!sdev)
1595                 return 0;
1596
1597         lu = sdev->hostdata;
1598
1599         return sprintf(buf, "%016llx:%06x:%04x\n",
1600                         (unsigned long long)lu->tgt->guid,
1601                         lu->tgt->directory_id, lu->lun);
1602 }
1603
1604 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1605
1606 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1607         &dev_attr_ieee1394_id,
1608         NULL
1609 };
1610
1611 static struct scsi_host_template scsi_driver_template = {
1612         .module                 = THIS_MODULE,
1613         .name                   = "SBP-2 IEEE-1394",
1614         .proc_name              = sbp2_driver_name,
1615         .queuecommand           = sbp2_scsi_queuecommand,
1616         .slave_alloc            = sbp2_scsi_slave_alloc,
1617         .slave_configure        = sbp2_scsi_slave_configure,
1618         .eh_abort_handler       = sbp2_scsi_abort,
1619         .this_id                = -1,
1620         .sg_tablesize           = SG_ALL,
1621         .use_clustering         = ENABLE_CLUSTERING,
1622         .cmd_per_lun            = 1,
1623         .can_queue              = 1,
1624         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1625 };
1626
1627 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1628 MODULE_DESCRIPTION("SCSI over IEEE1394");
1629 MODULE_LICENSE("GPL");
1630 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1631
1632 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1633 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1634 MODULE_ALIAS("sbp2");
1635 #endif
1636
1637 static int __init sbp2_init(void)
1638 {
1639         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1640         if (!sbp2_wq)
1641                 return -ENOMEM;
1642
1643         return driver_register(&sbp2_driver.driver);
1644 }
1645
1646 static void __exit sbp2_cleanup(void)
1647 {
1648         driver_unregister(&sbp2_driver.driver);
1649         destroy_workqueue(sbp2_wq);
1650 }
1651
1652 module_init(sbp2_init);
1653 module_exit(sbp2_cleanup);