drivers/firewire/fw-sbp2.c

   1 /*
   2  * SBP2 driver (SCSI over IEEE1394)
   3  *
   4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22  * The basic structure of this driver is based on the old storage driver,
  23  * drivers/ieee1394/sbp2.c, originally written by
  24  *     James Goodwin <jamesg@filanet.com>
  25  * with later contributions and ongoing maintenance from
  26  *     Ben Collins <bcollins@debian.org>,
  27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  28  * and many others.
  29  */
  30
  31 #include <linux/blkdev.h>
  32 #include <linux/bug.h>
  33 #include <linux/delay.h>
  34 #include <linux/device.h>
  35 #include <linux/dma-mapping.h>
  36 #include <linux/kernel.h>
  37 #include <linux/mod_devicetable.h>
  38 #include <linux/module.h>
  39 #include <linux/moduleparam.h>
  40 #include <linux/scatterlist.h>
  41 #include <linux/string.h>
  42 #include <linux/stringify.h>
  43 #include <linux/timer.h>
  44 #include <linux/workqueue.h>
  45 #include <asm/system.h>
  46
  47 #include <scsi/scsi.h>
  48 #include <scsi/scsi_cmnd.h>
  49 #include <scsi/scsi_device.h>
  50 #include <scsi/scsi_host.h>
  51
  52 #include "fw-device.h"
  53 #include "fw-topology.h"
  54 #include "fw-transaction.h"
  55
  56 /*
  57  * So far only bridges from Oxford Semiconductor are known to support
  58  * concurrent logins. Depending on firmware, four or two concurrent logins
  59  * are possible on OXFW911 and newer Oxsemi bridges.
  60  *
  61  * Concurrent logins are useful together with cluster filesystems.
  62  */
  63 static int sbp2_param_exclusive_login = 1;
  64 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  65 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  66                  "(default = Y, use N for concurrent initiators)");
  67
  68 /*
  69  * Flags for firmware oddities
  70  *
  71  * - 128kB max transfer
  72  *   Limit transfer size. Necessary for some old bridges.
  73  *
  74  * - 36 byte inquiry
  75  *   When scsi_mod probes the device, let the inquiry command look like that
  76  *   from MS Windows.
  77  *
  78  * - skip mode page 8
  79  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  80  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  81  *
  82  * - fix capacity
  83  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  84  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  85  *   Don't use this with devices which don't have this bug.
  86  *
  87  * - delay inquiry
  88  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  89  *
  90  * - power condition
  91  *   Set the power condition field in the START STOP UNIT commands sent by
  92  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  93  *   Some disks need this to spin down or to resume properly.
  94  *
  95  * - override internal blacklist
  96  *   Instead of adding to the built-in blacklist, use only the workarounds
  97  *   specified in the module load parameter.
  98  *   Useful if a blacklist entry interfered with a non-broken device.
  99  */
 100 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 101 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 102 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 103 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 104 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 105 #define SBP2_INQUIRY_DELAY              12
 106 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 107 #define SBP2_WORKAROUND_OVERRIDE        0x100
 108
 109 static int sbp2_param_workarounds;
 110 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 111 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 112         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 113         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 114         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 115         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 116         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 117         ", set power condition in start stop unit = "
 118                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 119         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 120         ", or a combination)");
 121
 122 /* I don't know why the SCSI stack doesn't define something like this... */
 123 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
 124
 125 static const char sbp2_driver_name[] = "sbp2";
 126
 127 /*
 128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 129  * and one struct scsi_device per sbp2_logical_unit.
 130  */
 131 struct sbp2_logical_unit {
 132         struct sbp2_target *tgt;
 133         struct list_head link;
 134         struct fw_address_handler address_handler;
 135         struct list_head orb_list;
 136
 137         u64 command_block_agent_address;
 138         u16 lun;
 139         int login_id;
 140
 141         /*
 142          * The generation is updated once we've logged in or reconnected
 143          * to the logical unit.  Thus, I/O to the device will automatically
 144          * fail and get retried if it happens in a window where the device
 145          * is not ready, e.g. after a bus reset but before we reconnect.
 146          */
 147         int generation;
 148         int retries;
 149         struct delayed_work work;
 150         bool has_sdev;
 151         bool blocked;
 152 };
 153
 154 /*
 155  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 156  * and one struct Scsi_Host per sbp2_target.
 157  */
 158 struct sbp2_target {
 159         struct kref kref;
 160         struct fw_unit *unit;
 161         const char *bus_id;
 162         struct list_head lu_list;
 163
 164         u64 management_agent_address;
 165         u64 guid;
 166         int directory_id;
 167         int node_id;
 168         int address_high;
 169         unsigned int workarounds;
 170         unsigned int mgt_orb_timeout;
 171
 172         int dont_block; /* counter for each logical unit */
 173         int blocked;    /* ditto */
 174 };
 175
 176 /* Impossible login_id, to detect logout attempt before successful login */
 177 #define INVALID_LOGIN_ID 0x10000
 178
 179 /*
 180  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
 181  * provided in the config rom. Most devices do provide a value, which
 182  * we'll use for login management orbs, but with some sane limits.
 183  */
 184 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
 185 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
 186 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
 187 #define SBP2_ORB_NULL                   0x80000000
 188 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 189 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 190
 191 /*
 192  * The default maximum s/g segment size of a FireWire controller is
 193  * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
 194  * be quadlet-aligned, we set the length limit to 0xffff & ~3.
 195  */
 196 #define SBP2_MAX_SEG_SIZE               0xfffc
 197
 198 /* Unit directory keys */
 199 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 200 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 201 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 202 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 203
 204 /* Management orb opcodes */
 205 #define SBP2_LOGIN_REQUEST              0x0
 206 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 207 #define SBP2_RECONNECT_REQUEST          0x3
 208 #define SBP2_SET_PASSWORD_REQUEST       0x4
 209 #define SBP2_LOGOUT_REQUEST             0x7
 210 #define SBP2_ABORT_TASK_REQUEST         0xb
 211 #define SBP2_ABORT_TASK_SET             0xc
 212 #define SBP2_LOGICAL_UNIT_RESET         0xe
 213 #define SBP2_TARGET_RESET_REQUEST       0xf
 214
 215 /* Offsets for command block agent registers */
 216 #define SBP2_AGENT_STATE                0x00
 217 #define SBP2_AGENT_RESET                0x04
 218 #define SBP2_ORB_POINTER                0x08
 219 #define SBP2_DOORBELL                   0x10
 220 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 221
 222 /* Status write response codes */
 223 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 224 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 225 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 226 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 227
 228 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 229 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 230 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 231 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 232 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 233 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 234 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 235 #define STATUS_GET_DATA(v)              ((v).data)
 236
 237 struct sbp2_status {
 238         u32 status;
 239         u32 orb_low;
 240         u8 data[24];
 241 };
 242
 243 struct sbp2_pointer {
 244         __be32 high;
 245         __be32 low;
 246 };
 247
 248 struct sbp2_orb {
 249         struct fw_transaction t;
 250         struct kref kref;
 251         dma_addr_t request_bus;
 252         int rcode;
 253         struct sbp2_pointer pointer;
 254         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 255         struct list_head link;
 256 };
 257
 258 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 259 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 260 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 261 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 262 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 263 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 264
 265 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 266 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 267
 268 struct sbp2_management_orb {
 269         struct sbp2_orb base;
 270         struct {
 271                 struct sbp2_pointer password;
 272                 struct sbp2_pointer response;
 273                 __be32 misc;
 274                 __be32 length;
 275                 struct sbp2_pointer status_fifo;
 276         } request;
 277         __be32 response[4];
 278         dma_addr_t response_bus;
 279         struct completion done;
 280         struct sbp2_status status;
 281 };
 282
 283 struct sbp2_login_response {
 284         __be32 misc;
 285         struct sbp2_pointer command_block_agent;
 286         __be32 reconnect_hold;
 287 };
 288 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 289 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 290 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 291 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 292 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 293 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 294 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 295 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 296
 297 struct sbp2_command_orb {
 298         struct sbp2_orb base;
 299         struct {
 300                 struct sbp2_pointer next;
 301                 struct sbp2_pointer data_descriptor;
 302                 __be32 misc;
 303                 u8 command_block[12];
 304         } request;
 305         struct scsi_cmnd *cmd;
 306         scsi_done_fn_t done;
 307         struct sbp2_logical_unit *lu;
 308
 309         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 310         dma_addr_t page_table_bus;
 311 };
 312
 313 /*
 314  * List of devices with known bugs.
 315  *
 316  * The firmware_revision field, masked with 0xffff00, is the best
 317  * indicator for the type of bridge chip of a device.  It yields a few
 318  * false positives but this did not break correctly behaving devices
 319  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
 320  * from the config rom can never match that.
 321  */
 322 static const struct {
 323         u32 firmware_revision;
 324         u32 model;
 325         unsigned int workarounds;
 326 } sbp2_workarounds_table[] = {
 327         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 328                 .firmware_revision      = 0x002800,
 329                 .model                  = 0x001010,
 330                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 331                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 332                                           SBP2_WORKAROUND_POWER_CONDITION,
 333         },
 334         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 335                 .firmware_revision      = 0x002800,
 336                 .model                  = 0x000000,
 337                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
 338                                           SBP2_WORKAROUND_POWER_CONDITION,
 339         },
 340         /* Initio bridges, actually only needed for some older ones */ {
 341                 .firmware_revision      = 0x000200,
 342                 .model                  = ~0,
 343                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 344         },
 345         /* PL-3507 bridge with Prolific firmware */ {
 346                 .firmware_revision      = 0x012800,
 347                 .model                  = ~0,
 348                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 349         },
 350         /* Symbios bridge */ {
 351                 .firmware_revision      = 0xa0b800,
 352                 .model                  = ~0,
 353                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 354         },
 355         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 356                 .firmware_revision      = 0x002600,
 357                 .model                  = ~0,
 358                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 359         },
 360
 361         /*
 362          * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
 363          * these iPods do not feature the read_capacity bug according
 364          * to one report.  Read_capacity behaviour as well as model_id
 365          * could change due to Apple-supplied firmware updates though.
 366          */
 367
 368         /* iPod 4th generation. */ {
 369                 .firmware_revision      = 0x0a2700,
 370                 .model                  = 0x000021,
 371                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 372         },
 373         /* iPod mini */ {
 374                 .firmware_revision      = 0x0a2700,
 375                 .model                  = 0x000023,
 376                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 377         },
 378         /* iPod Photo */ {
 379                 .firmware_revision      = 0x0a2700,
 380                 .model                  = 0x00007e,
 381                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 382         }
 383 };
 384
 385 static void
 386 free_orb(struct kref *kref)
 387 {
 388         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 389
 390         kfree(orb);
 391 }
 392
 393 static void
 394 sbp2_status_write(struct fw_card *card, struct fw_request *request,
 395                   int tcode, int destination, int source,
 396                   int generation, int speed,
 397                   unsigned long long offset,
 398                   void *payload, size_t length, void *callback_data)
 399 {
 400         struct sbp2_logical_unit *lu = callback_data;
 401         struct sbp2_orb *orb;
 402         struct sbp2_status status;
 403         size_t header_size;
 404         unsigned long flags;
 405
 406         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 407             length == 0 || length > sizeof(status)) {
 408                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 409                 return;
 410         }
 411
 412         header_size = min(length, 2 * sizeof(u32));
 413         fw_memcpy_from_be32(&status, payload, header_size);
 414         if (length > header_size)
 415                 memcpy(status.data, payload + 8, length - header_size);
 416         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 417                 fw_notify("non-orb related status write, not handled\n");
 418                 fw_send_response(card, request, RCODE_COMPLETE);
 419                 return;
 420         }
 421
 422         /* Lookup the orb corresponding to this status write. */
 423         spin_lock_irqsave(&card->lock, flags);
 424         list_for_each_entry(orb, &lu->orb_list, link) {
 425                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 426                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 427                         orb->rcode = RCODE_COMPLETE;
 428                         list_del(&orb->link);
 429                         break;
 430                 }
 431         }
 432         spin_unlock_irqrestore(&card->lock, flags);
 433
 434         if (&orb->link != &lu->orb_list)
 435                 orb->callback(orb, &status);
 436         else
 437                 fw_error("status write for unknown orb\n");
 438
 439         kref_put(&orb->kref, free_orb);
 440
 441         fw_send_response(card, request, RCODE_COMPLETE);
 442 }
 443
 444 static void
 445 complete_transaction(struct fw_card *card, int rcode,
 446                      void *payload, size_t length, void *data)
 447 {
 448         struct sbp2_orb *orb = data;
 449         unsigned long flags;
 450
 451         /*
 452          * This is a little tricky.  We can get the status write for
 453          * the orb before we get this callback.  The status write
 454          * handler above will assume the orb pointer transaction was
 455          * successful and set the rcode to RCODE_COMPLETE for the orb.
 456          * So this callback only sets the rcode if it hasn't already
 457          * been set and only does the cleanup if the transaction
 458          * failed and we didn't already get a status write.
 459          */
 460         spin_lock_irqsave(&card->lock, flags);
 461
 462         if (orb->rcode == -1)
 463                 orb->rcode = rcode;
 464         if (orb->rcode != RCODE_COMPLETE) {
 465                 list_del(&orb->link);
 466                 spin_unlock_irqrestore(&card->lock, flags);
 467                 orb->callback(orb, NULL);
 468         } else {
 469                 spin_unlock_irqrestore(&card->lock, flags);
 470         }
 471
 472         kref_put(&orb->kref, free_orb);
 473 }
 474
 475 static void
 476 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 477               int node_id, int generation, u64 offset)
 478 {
 479         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 480         unsigned long flags;
 481
 482         orb->pointer.high = 0;
 483         orb->pointer.low = cpu_to_be32(orb->request_bus);
 484
 485         spin_lock_irqsave(&device->card->lock, flags);
 486         list_add_tail(&orb->link, &lu->orb_list);
 487         spin_unlock_irqrestore(&device->card->lock, flags);
 488
 489         /* Take a ref for the orb list and for the transaction callback. */
 490         kref_get(&orb->kref);
 491         kref_get(&orb->kref);
 492
 493         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 494                         node_id, generation, device->max_speed, offset,
 495                         &orb->pointer, sizeof(orb->pointer),
 496                         complete_transaction, orb);
 497 }
 498
 499 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 500 {
 501         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 502         struct sbp2_orb *orb, *next;
 503         struct list_head list;
 504         unsigned long flags;
 505         int retval = -ENOENT;
 506
 507         INIT_LIST_HEAD(&list);
 508         spin_lock_irqsave(&device->card->lock, flags);
 509         list_splice_init(&lu->orb_list, &list);
 510         spin_unlock_irqrestore(&device->card->lock, flags);
 511
 512         list_for_each_entry_safe(orb, next, &list, link) {
 513                 retval = 0;
 514                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 515                         continue;
 516
 517                 orb->rcode = RCODE_CANCELLED;
 518                 orb->callback(orb, NULL);
 519         }
 520
 521         return retval;
 522 }
 523
 524 static void
 525 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 526 {
 527         struct sbp2_management_orb *orb =
 528                 container_of(base_orb, struct sbp2_management_orb, base);
 529
 530         if (status)
 531                 memcpy(&orb->status, status, sizeof(*status));
 532         complete(&orb->done);
 533 }
 534
 535 static int
 536 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 537                          int generation, int function, int lun_or_login_id,
 538                          void *response)
 539 {
 540         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 541         struct sbp2_management_orb *orb;
 542         unsigned int timeout;
 543         int retval = -ENOMEM;
 544
 545         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 546                 return 0;
 547
 548         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 549         if (orb == NULL)
 550                 return -ENOMEM;
 551
 552         kref_init(&orb->base.kref);
 553         orb->response_bus =
 554                 dma_map_single(device->card->device, &orb->response,
 555                                sizeof(orb->response), DMA_FROM_DEVICE);
 556         if (dma_mapping_error(device->card->device, orb->response_bus))
 557                 goto fail_mapping_response;
 558
 559         orb->request.response.high = 0;
 560         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 561
 562         orb->request.misc = cpu_to_be32(
 563                 MANAGEMENT_ORB_NOTIFY |
 564                 MANAGEMENT_ORB_FUNCTION(function) |
 565                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 566         orb->request.length = cpu_to_be32(
 567                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 568
 569         orb->request.status_fifo.high =
 570                 cpu_to_be32(lu->address_handler.offset >> 32);
 571         orb->request.status_fifo.low  =
 572                 cpu_to_be32(lu->address_handler.offset);
 573
 574         if (function == SBP2_LOGIN_REQUEST) {
 575                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 576                 orb->request.misc |= cpu_to_be32(
 577                         MANAGEMENT_ORB_RECONNECT(2) |
 578                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 579                 timeout = lu->tgt->mgt_orb_timeout;
 580         } else {
 581                 timeout = SBP2_ORB_TIMEOUT;
 582         }
 583
 584         init_completion(&orb->done);
 585         orb->base.callback = complete_management_orb;
 586
 587         orb->base.request_bus =
 588                 dma_map_single(device->card->device, &orb->request,
 589                                sizeof(orb->request), DMA_TO_DEVICE);
 590         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 591                 goto fail_mapping_request;
 592
 593         sbp2_send_orb(&orb->base, lu, node_id, generation,
 594                       lu->tgt->management_agent_address);
 595
 596         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 597
 598         retval = -EIO;
 599         if (sbp2_cancel_orbs(lu) == 0) {
 600                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 601                          lu->tgt->bus_id, orb->base.rcode);
 602                 goto out;
 603         }
 604
 605         if (orb->base.rcode != RCODE_COMPLETE) {
 606                 fw_error("%s: management write failed, rcode 0x%02x\n",
 607                          lu->tgt->bus_id, orb->base.rcode);
 608                 goto out;
 609         }
 610
 611         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 612             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 613                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 614                          STATUS_GET_RESPONSE(orb->status),
 615                          STATUS_GET_SBP_STATUS(orb->status));
 616                 goto out;
 617         }
 618
 619         retval = 0;
 620  out:
 621         dma_unmap_single(device->card->device, orb->base.request_bus,
 622                          sizeof(orb->request), DMA_TO_DEVICE);
 623  fail_mapping_request:
 624         dma_unmap_single(device->card->device, orb->response_bus,
 625                          sizeof(orb->response), DMA_FROM_DEVICE);
 626  fail_mapping_response:
 627         if (response)
 628                 memcpy(response, orb->response, sizeof(orb->response));
 629         kref_put(&orb->base.kref, free_orb);
 630
 631         return retval;
 632 }
 633
 634 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 635 {
 636         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 637         __be32 d = 0;
 638
 639         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 640                            lu->tgt->node_id, lu->generation, device->max_speed,
 641                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 642                            &d, sizeof(d));
 643 }
 644
 645 static void
 646 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 647                                    void *payload, size_t length, void *data)
 648 {
 649         kfree(data);
 650 }
 651
 652 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 653 {
 654         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 655         struct fw_transaction *t;
 656         static __be32 d;
 657
 658         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 659         if (t == NULL)
 660                 return;
 661
 662         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 663                         lu->tgt->node_id, lu->generation, device->max_speed,
 664                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 665                         &d, sizeof(d), complete_agent_reset_write_no_wait, t);
 666 }
 667
 668 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
 669 {
 670         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
 671         unsigned long flags;
 672
 673         /* serialize with comparisons of lu->generation and card->generation */
 674         spin_lock_irqsave(&card->lock, flags);
 675         lu->generation = generation;
 676         spin_unlock_irqrestore(&card->lock, flags);
 677 }
 678
 679 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 680 {
 681         /*
 682          * We may access dont_block without taking card->lock here:
 683          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 684          * are currently serialized against each other.
 685          * And a wrong result in sbp2_conditionally_block()'s access of
 686          * dont_block is rather harmless, it simply misses its first chance.
 687          */
 688         --lu->tgt->dont_block;
 689 }
 690
 691 /*
 692  * Blocks lu->tgt if all of the following conditions are met:
 693  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 694  *     logical units have been finished (indicated by dont_block == 0).
 695  *   - lu->generation is stale.
 696  *
 697  * Note, scsi_block_requests() must be called while holding card->lock,
 698  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 699  * unblock the target.
 700  */
 701 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 702 {
 703         struct sbp2_target *tgt = lu->tgt;
 704         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 705         struct Scsi_Host *shost =
 706                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 707         unsigned long flags;
 708
 709         spin_lock_irqsave(&card->lock, flags);
 710         if (!tgt->dont_block && !lu->blocked &&
 711             lu->generation != card->generation) {
 712                 lu->blocked = true;
 713                 if (++tgt->blocked == 1)
 714                         scsi_block_requests(shost);
 715         }
 716         spin_unlock_irqrestore(&card->lock, flags);
 717 }
 718
 719 /*
 720  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 721  * Note, it is harmless to run scsi_unblock_requests() outside the
 722  * card->lock protected section.  On the other hand, running it inside
 723  * the section might clash with shost->host_lock.
 724  */
 725 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 726 {
 727         struct sbp2_target *tgt = lu->tgt;
 728         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 729         struct Scsi_Host *shost =
 730                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 731         unsigned long flags;
 732         bool unblock = false;
 733
 734         spin_lock_irqsave(&card->lock, flags);
 735         if (lu->blocked && lu->generation == card->generation) {
 736                 lu->blocked = false;
 737                 unblock = --tgt->blocked == 0;
 738         }
 739         spin_unlock_irqrestore(&card->lock, flags);
 740
 741         if (unblock)
 742                 scsi_unblock_requests(shost);
 743 }
 744
 745 /*
 746  * Prevents future blocking of tgt and unblocks it.
 747  * Note, it is harmless to run scsi_unblock_requests() outside the
 748  * card->lock protected section.  On the other hand, running it inside
 749  * the section might clash with shost->host_lock.
 750  */
 751 static void sbp2_unblock(struct sbp2_target *tgt)
 752 {
 753         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 754         struct Scsi_Host *shost =
 755                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 756         unsigned long flags;
 757
 758         spin_lock_irqsave(&card->lock, flags);
 759         ++tgt->dont_block;
 760         spin_unlock_irqrestore(&card->lock, flags);
 761
 762         scsi_unblock_requests(shost);
 763 }
 764
 765 static int sbp2_lun2int(u16 lun)
 766 {
 767         struct scsi_lun eight_bytes_lun;
 768
 769         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 770         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 771         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 772
 773         return scsilun_to_int(&eight_bytes_lun);
 774 }
 775
 776 static void sbp2_release_target(struct kref *kref)
 777 {
 778         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 779         struct sbp2_logical_unit *lu, *next;
 780         struct Scsi_Host *shost =
 781                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 782         struct scsi_device *sdev;
 783         struct fw_device *device = fw_device(tgt->unit->device.parent);
 784
 785         /* prevent deadlocks */
 786         sbp2_unblock(tgt);
 787
 788         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 789                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 790                 if (sdev) {
 791                         scsi_remove_device(sdev);
 792                         scsi_device_put(sdev);
 793                 }
 794                 if (lu->login_id != INVALID_LOGIN_ID) {
 795                         int generation, node_id;
 796                         /*
 797                          * tgt->node_id may be obsolete here if we failed
 798                          * during initial login or after a bus reset where
 799                          * the topology changed.
 800                          */
 801                         generation = device->generation;
 802                         smp_rmb(); /* node_id vs. generation */
 803                         node_id    = device->node_id;
 804                         sbp2_send_management_orb(lu, node_id, generation,
 805                                                  SBP2_LOGOUT_REQUEST,
 806                                                  lu->login_id, NULL);
 807                 }
 808                 fw_core_remove_address_handler(&lu->address_handler);
 809                 list_del(&lu->link);
 810                 kfree(lu);
 811         }
 812         scsi_remove_host(shost);
 813         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
 814
 815         fw_unit_put(tgt->unit);
 816         scsi_host_put(shost);
 817         fw_device_put(device);
 818 }
 819
 820 static struct workqueue_struct *sbp2_wq;
 821
 822 static void sbp2_target_put(struct sbp2_target *tgt)
 823 {
 824         kref_put(&tgt->kref, sbp2_release_target);
 825 }
 826
 827 /*
 828  * Always get the target's kref when scheduling work on one its units.
 829  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 830  */
 831 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 832 {
 833         kref_get(&lu->tgt->kref);
 834         if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
 835                 sbp2_target_put(lu->tgt);
 836 }
 837
 838 /*
 839  * Write retransmit retry values into the BUSY_TIMEOUT register.
 840  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 841  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 842  *   saner value after logging into the device.
 843  * - The dual-phase retry protocol is optional to implement, and if not
 844  *   supported, writes to the dual-phase portion of the register will be
 845  *   ignored. We try to write the original 1394-1995 default here.
 846  * - In the case of devices that are also SBP-3-compliant, all writes are
 847  *   ignored, as the register is read-only, but contains single-phase retry of
 848  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 849  *   write attempt is safe and yields more consistent behavior for all devices.
 850  *
 851  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 852  * and section 6.4 of the SBP-3 spec for further details.
 853  */
 854 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 855 {
 856         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 857         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 858
 859         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 860                            lu->tgt->node_id, lu->generation, device->max_speed,
 861                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
 862                            &d, sizeof(d));
 863 }
 864
 865 static void sbp2_reconnect(struct work_struct *work);
 866
 867 static void sbp2_login(struct work_struct *work)
 868 {
 869         struct sbp2_logical_unit *lu =
 870                 container_of(work, struct sbp2_logical_unit, work.work);
 871         struct sbp2_target *tgt = lu->tgt;
 872         struct fw_device *device = fw_device(tgt->unit->device.parent);
 873         struct Scsi_Host *shost;
 874         struct scsi_device *sdev;
 875         struct sbp2_login_response response;
 876         int generation, node_id, local_node_id;
 877
 878         if (fw_device_is_shutdown(device))
 879                 goto out;
 880
 881         generation    = device->generation;
 882         smp_rmb();    /* node_id must not be older than generation */
 883         node_id       = device->node_id;
 884         local_node_id = device->card->node_id;
 885
 886         /* If this is a re-login attempt, log out, or we might be rejected. */
 887         if (lu->has_sdev)
 888                 sbp2_send_management_orb(lu, device->node_id, generation,
 889                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 890
 891         if (sbp2_send_management_orb(lu, node_id, generation,
 892                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 893                 if (lu->retries++ < 5) {
 894                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 895                 } else {
 896                         fw_error("%s: failed to login to LUN %04x\n",
 897                                  tgt->bus_id, lu->lun);
 898                         /* Let any waiting I/O fail from now on. */
 899                         sbp2_unblock(lu->tgt);
 900                 }
 901                 goto out;
 902         }
 903
 904         tgt->node_id      = node_id;
 905         tgt->address_high = local_node_id << 16;
 906         sbp2_set_generation(lu, 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 != ~0)
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         /* Initialize to values that won't match anything in our table. */
1151         firmware_revision = 0xff000000;
1152         model = 0xff000000;
1153
1154         /* implicit directory ID */
1155         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1156                              + CSR_CONFIG_ROM) & 0xffffff;
1157
1158         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1159                                &firmware_revision) < 0)
1160                 goto fail_tgt_put;
1161
1162         sbp2_init_workarounds(tgt, model, firmware_revision);
1163
1164         /* Do the login in a workqueue so we can easily reschedule retries. */
1165         list_for_each_entry(lu, &tgt->lu_list, link)
1166                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1167         return 0;
1168
1169  fail_tgt_put:
1170         sbp2_target_put(tgt);
1171         return -ENOMEM;
1172
1173  fail_shost_put:
1174         scsi_host_put(shost);
1175         return -ENOMEM;
1176 }
1177
1178 static int sbp2_remove(struct device *dev)
1179 {
1180         struct fw_unit *unit = fw_unit(dev);
1181         struct sbp2_target *tgt = unit->device.driver_data;
1182
1183         sbp2_target_put(tgt);
1184         return 0;
1185 }
1186
1187 static void sbp2_reconnect(struct work_struct *work)
1188 {
1189         struct sbp2_logical_unit *lu =
1190                 container_of(work, struct sbp2_logical_unit, work.work);
1191         struct sbp2_target *tgt = lu->tgt;
1192         struct fw_device *device = fw_device(tgt->unit->device.parent);
1193         int generation, node_id, local_node_id;
1194
1195         if (fw_device_is_shutdown(device))
1196                 goto out;
1197
1198         generation    = device->generation;
1199         smp_rmb();    /* node_id must not be older than generation */
1200         node_id       = device->node_id;
1201         local_node_id = device->card->node_id;
1202
1203         if (sbp2_send_management_orb(lu, node_id, generation,
1204                                      SBP2_RECONNECT_REQUEST,
1205                                      lu->login_id, NULL) < 0) {
1206                 /*
1207                  * If reconnect was impossible even though we are in the
1208                  * current generation, fall back and try to log in again.
1209                  *
1210                  * We could check for "Function rejected" status, but
1211                  * looking at the bus generation as simpler and more general.
1212                  */
1213                 smp_rmb(); /* get current card generation */
1214                 if (generation == device->card->generation ||
1215                     lu->retries++ >= 5) {
1216                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1217                         lu->retries = 0;
1218                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1219                 }
1220                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1221                 goto out;
1222         }
1223
1224         tgt->node_id      = node_id;
1225         tgt->address_high = local_node_id << 16;
1226         sbp2_set_generation(lu, generation);
1227
1228         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1229                   tgt->bus_id, lu->lun, lu->retries);
1230
1231         sbp2_agent_reset(lu);
1232         sbp2_cancel_orbs(lu);
1233         sbp2_conditionally_unblock(lu);
1234  out:
1235         sbp2_target_put(tgt);
1236 }
1237
1238 static void sbp2_update(struct fw_unit *unit)
1239 {
1240         struct sbp2_target *tgt = unit->device.driver_data;
1241         struct sbp2_logical_unit *lu;
1242
1243         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1244
1245         /*
1246          * Fw-core serializes sbp2_update() against sbp2_remove().
1247          * Iteration over tgt->lu_list is therefore safe here.
1248          */
1249         list_for_each_entry(lu, &tgt->lu_list, link) {
1250                 sbp2_conditionally_block(lu);
1251                 lu->retries = 0;
1252                 sbp2_queue_work(lu, 0);
1253         }
1254 }
1255
1256 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1257 #define SBP2_SW_VERSION_ENTRY   0x00010483
1258
1259 static const struct fw_device_id sbp2_id_table[] = {
1260         {
1261                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1262                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1263                 .version      = SBP2_SW_VERSION_ENTRY,
1264         },
1265         { }
1266 };
1267
1268 static struct fw_driver sbp2_driver = {
1269         .driver   = {
1270                 .owner  = THIS_MODULE,
1271                 .name   = sbp2_driver_name,
1272                 .bus    = &fw_bus_type,
1273                 .probe  = sbp2_probe,
1274                 .remove = sbp2_remove,
1275         },
1276         .update   = sbp2_update,
1277         .id_table = sbp2_id_table,
1278 };
1279
1280 static unsigned int
1281 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1282 {
1283         int sam_status;
1284
1285         sense_data[0] = 0x70;
1286         sense_data[1] = 0x0;
1287         sense_data[2] = sbp2_status[1];
1288         sense_data[3] = sbp2_status[4];
1289         sense_data[4] = sbp2_status[5];
1290         sense_data[5] = sbp2_status[6];
1291         sense_data[6] = sbp2_status[7];
1292         sense_data[7] = 10;
1293         sense_data[8] = sbp2_status[8];
1294         sense_data[9] = sbp2_status[9];
1295         sense_data[10] = sbp2_status[10];
1296         sense_data[11] = sbp2_status[11];
1297         sense_data[12] = sbp2_status[2];
1298         sense_data[13] = sbp2_status[3];
1299         sense_data[14] = sbp2_status[12];
1300         sense_data[15] = sbp2_status[13];
1301
1302         sam_status = sbp2_status[0] & 0x3f;
1303
1304         switch (sam_status) {
1305         case SAM_STAT_GOOD:
1306         case SAM_STAT_CHECK_CONDITION:
1307         case SAM_STAT_CONDITION_MET:
1308         case SAM_STAT_BUSY:
1309         case SAM_STAT_RESERVATION_CONFLICT:
1310         case SAM_STAT_COMMAND_TERMINATED:
1311                 return DID_OK << 16 | sam_status;
1312
1313         default:
1314                 return DID_ERROR << 16;
1315         }
1316 }
1317
1318 static void
1319 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1320 {
1321         struct sbp2_command_orb *orb =
1322                 container_of(base_orb, struct sbp2_command_orb, base);
1323         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1324         int result;
1325
1326         if (status != NULL) {
1327                 if (STATUS_GET_DEAD(*status))
1328                         sbp2_agent_reset_no_wait(orb->lu);
1329
1330                 switch (STATUS_GET_RESPONSE(*status)) {
1331                 case SBP2_STATUS_REQUEST_COMPLETE:
1332                         result = DID_OK << 16;
1333                         break;
1334                 case SBP2_STATUS_TRANSPORT_FAILURE:
1335                         result = DID_BUS_BUSY << 16;
1336                         break;
1337                 case SBP2_STATUS_ILLEGAL_REQUEST:
1338                 case SBP2_STATUS_VENDOR_DEPENDENT:
1339                 default:
1340                         result = DID_ERROR << 16;
1341                         break;
1342                 }
1343
1344                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1345                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1346                                                            orb->cmd->sense_buffer);
1347         } else {
1348                 /*
1349                  * If the orb completes with status == NULL, something
1350                  * went wrong, typically a bus reset happened mid-orb
1351                  * or when sending the write (less likely).
1352                  */
1353                 result = DID_BUS_BUSY << 16;
1354                 sbp2_conditionally_block(orb->lu);
1355         }
1356
1357         dma_unmap_single(device->card->device, orb->base.request_bus,
1358                          sizeof(orb->request), DMA_TO_DEVICE);
1359
1360         if (scsi_sg_count(orb->cmd) > 0)
1361                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1362                              scsi_sg_count(orb->cmd),
1363                              orb->cmd->sc_data_direction);
1364
1365         if (orb->page_table_bus != 0)
1366                 dma_unmap_single(device->card->device, orb->page_table_bus,
1367                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1368
1369         orb->cmd->result = result;
1370         orb->done(orb->cmd);
1371 }
1372
1373 static int
1374 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1375                      struct sbp2_logical_unit *lu)
1376 {
1377         struct scatterlist *sg = scsi_sglist(orb->cmd);
1378         int i, n;
1379
1380         n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1381                        orb->cmd->sc_data_direction);
1382         if (n == 0)
1383                 goto fail;
1384
1385         /*
1386          * Handle the special case where there is only one element in
1387          * the scatter list by converting it to an immediate block
1388          * request. This is also a workaround for broken devices such
1389          * as the second generation iPod which doesn't support page
1390          * tables.
1391          */
1392         if (n == 1) {
1393                 orb->request.data_descriptor.high =
1394                         cpu_to_be32(lu->tgt->address_high);
1395                 orb->request.data_descriptor.low  =
1396                         cpu_to_be32(sg_dma_address(sg));
1397                 orb->request.misc |=
1398                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1399                 return 0;
1400         }
1401
1402         for_each_sg(sg, sg, n, i) {
1403                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1404                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1405         }
1406
1407         orb->page_table_bus =
1408                 dma_map_single(device->card->device, orb->page_table,
1409                                sizeof(orb->page_table), DMA_TO_DEVICE);
1410         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1411                 goto fail_page_table;
1412
1413         /*
1414          * The data_descriptor pointer is the one case where we need
1415          * to fill in the node ID part of the address.  All other
1416          * pointers assume that the data referenced reside on the
1417          * initiator (i.e. us), but data_descriptor can refer to data
1418          * on other nodes so we need to put our ID in descriptor.high.
1419          */
1420         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1421         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1422         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1423                                          COMMAND_ORB_DATA_SIZE(n));
1424
1425         return 0;
1426
1427  fail_page_table:
1428         dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1429                      scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
1430  fail:
1431         return -ENOMEM;
1432 }
1433
1434 /* SCSI stack integration */
1435
1436 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1437 {
1438         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1439         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1440         struct sbp2_command_orb *orb;
1441         unsigned int max_payload;
1442         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1443
1444         /*
1445          * Bidirectional commands are not yet implemented, and unknown
1446          * transfer direction not handled.
1447          */
1448         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1449                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1450                 cmd->result = DID_ERROR << 16;
1451                 done(cmd);
1452                 return 0;
1453         }
1454
1455         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1456         if (orb == NULL) {
1457                 fw_notify("failed to alloc orb\n");
1458                 return SCSI_MLQUEUE_HOST_BUSY;
1459         }
1460
1461         /* Initialize rcode to something not RCODE_COMPLETE. */
1462         orb->base.rcode = -1;
1463         kref_init(&orb->base.kref);
1464
1465         orb->lu   = lu;
1466         orb->done = done;
1467         orb->cmd  = cmd;
1468
1469         orb->request.next.high   = cpu_to_be32(SBP2_ORB_NULL);
1470         /*
1471          * At speed 100 we can do 512 bytes per packet, at speed 200,
1472          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1473          * specifies the max payload size as 2 ^ (max_payload + 2), so
1474          * if we set this to max_speed + 7, we get the right value.
1475          */
1476         max_payload = min(device->max_speed + 7,
1477                           device->card->max_receive - 1);
1478         orb->request.misc = cpu_to_be32(
1479                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1480                 COMMAND_ORB_SPEED(device->max_speed) |
1481                 COMMAND_ORB_NOTIFY);
1482
1483         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1484                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1485
1486         generation = device->generation;
1487         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1488
1489         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1490                 goto out;
1491
1492         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1493
1494         orb->base.callback = complete_command_orb;
1495         orb->base.request_bus =
1496                 dma_map_single(device->card->device, &orb->request,
1497                                sizeof(orb->request), DMA_TO_DEVICE);
1498         if (dma_mapping_error(device->card->device, orb->base.request_bus))
1499                 goto out;
1500
1501         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1502                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1503         retval = 0;
1504  out:
1505         kref_put(&orb->base.kref, free_orb);
1506         return retval;
1507 }
1508
1509 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1510 {
1511         struct sbp2_logical_unit *lu = sdev->hostdata;
1512
1513         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1514         if (!lu)
1515                 return -ENOSYS;
1516
1517         sdev->allow_restart = 1;
1518
1519         /* SBP-2 requires quadlet alignment of the data buffers. */
1520         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1521
1522         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1523                 sdev->inquiry_len = 36;
1524
1525         return 0;
1526 }
1527
1528 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1529 {
1530         struct sbp2_logical_unit *lu = sdev->hostdata;
1531
1532         sdev->use_10_for_rw = 1;
1533
1534         if (sbp2_param_exclusive_login)
1535                 sdev->manage_start_stop = 1;
1536
1537         if (sdev->type == TYPE_ROM)
1538                 sdev->use_10_for_ms = 1;
1539
1540         if (sdev->type == TYPE_DISK &&
1541             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1542                 sdev->skip_ms_page_8 = 1;
1543
1544         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1545                 sdev->fix_capacity = 1;
1546
1547         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1548                 sdev->start_stop_pwr_cond = 1;
1549
1550         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1551                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1552
1553         blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
1554
1555         return 0;
1556 }
1557
1558 /*
1559  * Called by scsi stack when something has really gone wrong.  Usually
1560  * called when a command has timed-out for some reason.
1561  */
1562 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1563 {
1564         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1565
1566         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1567         sbp2_agent_reset(lu);
1568         sbp2_cancel_orbs(lu);
1569
1570         return SUCCESS;
1571 }
1572
1573 /*
1574  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1575  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1576  *
1577  * This is the concatenation of target port identifier and logical unit
1578  * identifier as per SAM-2...SAM-4 annex A.
1579  */
1580 static ssize_t
1581 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1582                             char *buf)
1583 {
1584         struct scsi_device *sdev = to_scsi_device(dev);
1585         struct sbp2_logical_unit *lu;
1586
1587         if (!sdev)
1588                 return 0;
1589
1590         lu = sdev->hostdata;
1591
1592         return sprintf(buf, "%016llx:%06x:%04x\n",
1593                         (unsigned long long)lu->tgt->guid,
1594                         lu->tgt->directory_id, lu->lun);
1595 }
1596
1597 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1598
1599 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1600         &dev_attr_ieee1394_id,
1601         NULL
1602 };
1603
1604 static struct scsi_host_template scsi_driver_template = {
1605         .module                 = THIS_MODULE,
1606         .name                   = "SBP-2 IEEE-1394",
1607         .proc_name              = sbp2_driver_name,
1608         .queuecommand           = sbp2_scsi_queuecommand,
1609         .slave_alloc            = sbp2_scsi_slave_alloc,
1610         .slave_configure        = sbp2_scsi_slave_configure,
1611         .eh_abort_handler       = sbp2_scsi_abort,
1612         .this_id                = -1,
1613         .sg_tablesize           = SG_ALL,
1614         .use_clustering         = ENABLE_CLUSTERING,
1615         .cmd_per_lun            = 1,
1616         .can_queue              = 1,
1617         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1618 };
1619
1620 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1621 MODULE_DESCRIPTION("SCSI over IEEE1394");
1622 MODULE_LICENSE("GPL");
1623 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1624
1625 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1626 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1627 MODULE_ALIAS("sbp2");
1628 #endif
1629
1630 static int __init sbp2_init(void)
1631 {
1632         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1633         if (!sbp2_wq)
1634                 return -ENOMEM;
1635
1636         return driver_register(&sbp2_driver.driver);
1637 }
1638
1639 static void __exit sbp2_cleanup(void)
1640 {
1641         driver_unregister(&sbp2_driver.driver);
1642         destroy_workqueue(sbp2_wq);
1643 }
1644
1645 module_init(sbp2_init);
1646 module_exit(sbp2_cleanup);