err.no Git - linux-2.6/blob - 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/delay.h>
  33 #include <linux/device.h>
  34 #include <linux/dma-mapping.h>
  35 #include <linux/kernel.h>
  36 #include <linux/mod_devicetable.h>
  37 #include <linux/module.h>
  38 #include <linux/moduleparam.h>
  39 #include <linux/scatterlist.h>
  40 #include <linux/string.h>
  41 #include <linux/stringify.h>
  42 #include <linux/timer.h>
  43 #include <linux/workqueue.h>
  44 #include <asm/system.h>
  45
  46 #include <scsi/scsi.h>
  47 #include <scsi/scsi_cmnd.h>
  48 #include <scsi/scsi_device.h>
  49 #include <scsi/scsi_host.h>
  50
  51 #include "fw-device.h"
  52 #include "fw-topology.h"
  53 #include "fw-transaction.h"
  54
  55 /*
  56  * So far only bridges from Oxford Semiconductor are known to support
  57  * concurrent logins. Depending on firmware, four or two concurrent logins
  58  * are possible on OXFW911 and newer Oxsemi bridges.
  59  *
  60  * Concurrent logins are useful together with cluster filesystems.
  61  */
  62 static int sbp2_param_exclusive_login = 1;
  63 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  64 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  65                  "(default = Y, use N for concurrent initiators)");
  66
  67 /*
  68  * Flags for firmware oddities
  69  *
  70  * - 128kB max transfer
  71  *   Limit transfer size. Necessary for some old bridges.
  72  *
  73  * - 36 byte inquiry
  74  *   When scsi_mod probes the device, let the inquiry command look like that
  75  *   from MS Windows.
  76  *
  77  * - skip mode page 8
  78  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  79  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  80  *
  81  * - fix capacity
  82  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  83  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  84  *   Don't use this with devices which don't have this bug.
  85  *
  86  * - delay inquiry
  87  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  88  *
  89  * - override internal blacklist
  90  *   Instead of adding to the built-in blacklist, use only the workarounds
  91  *   specified in the module load parameter.
  92  *   Useful if a blacklist entry interfered with a non-broken device.
  93  */
  94 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
  95 #define SBP2_WORKAROUND_INQUIRY_36      0x2
  96 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
  97 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
  98 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
  99 #define SBP2_INQUIRY_DELAY              12
 100 #define SBP2_WORKAROUND_OVERRIDE        0x100
 101
 102 static int sbp2_param_workarounds;
 103 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 104 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 105         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 106         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 107         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 108         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 109         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 110         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 111         ", or a combination)");
 112
 113 /* I don't know why the SCSI stack doesn't define something like this... */
 114 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
 115
 116 static const char sbp2_driver_name[] = "sbp2";
 117
 118 /*
 119  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 120  * and one struct scsi_device per sbp2_logical_unit.
 121  */
 122 struct sbp2_logical_unit {
 123         struct sbp2_target *tgt;
 124         struct list_head link;
 125         struct fw_address_handler address_handler;
 126         struct list_head orb_list;
 127
 128         u64 command_block_agent_address;
 129         u16 lun;
 130         int login_id;
 131
 132         /*
 133          * The generation is updated once we've logged in or reconnected
 134          * to the logical unit.  Thus, I/O to the device will automatically
 135          * fail and get retried if it happens in a window where the device
 136          * is not ready, e.g. after a bus reset but before we reconnect.
 137          */
 138         int generation;
 139         int retries;
 140         struct delayed_work work;
 141         bool has_sdev;
 142         bool blocked;
 143 };
 144
 145 /*
 146  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 147  * and one struct Scsi_Host per sbp2_target.
 148  */
 149 struct sbp2_target {
 150         struct kref kref;
 151         struct fw_unit *unit;
 152         const char *bus_id;
 153         struct list_head lu_list;
 154
 155         u64 management_agent_address;
 156         int directory_id;
 157         int node_id;
 158         int address_high;
 159         unsigned int workarounds;
 160         unsigned int mgt_orb_timeout;
 161
 162         int dont_block; /* counter for each logical unit */
 163         int blocked;    /* ditto */
 164 };
 165
 166 /*
 167  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
 168  * provided in the config rom. Most devices do provide a value, which
 169  * we'll use for login management orbs, but with some sane limits.
 170  */
 171 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
 172 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
 173 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
 174 #define SBP2_ORB_NULL                   0x80000000
 175 #define SBP2_MAX_SG_ELEMENT_LENGTH      0xf000
 176 #define SBP2_RETRY_LIMIT                0xf     /* 15 retries */
 177
 178 #define SBP2_DIRECTION_TO_MEDIA         0x0
 179 #define SBP2_DIRECTION_FROM_MEDIA       0x1
 180
 181 /* Unit directory keys */
 182 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 183 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 184 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 185 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 186
 187 /* Management orb opcodes */
 188 #define SBP2_LOGIN_REQUEST              0x0
 189 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 190 #define SBP2_RECONNECT_REQUEST          0x3
 191 #define SBP2_SET_PASSWORD_REQUEST       0x4
 192 #define SBP2_LOGOUT_REQUEST             0x7
 193 #define SBP2_ABORT_TASK_REQUEST         0xb
 194 #define SBP2_ABORT_TASK_SET             0xc
 195 #define SBP2_LOGICAL_UNIT_RESET         0xe
 196 #define SBP2_TARGET_RESET_REQUEST       0xf
 197
 198 /* Offsets for command block agent registers */
 199 #define SBP2_AGENT_STATE                0x00
 200 #define SBP2_AGENT_RESET                0x04
 201 #define SBP2_ORB_POINTER                0x08
 202 #define SBP2_DOORBELL                   0x10
 203 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 204
 205 /* Status write response codes */
 206 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 207 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 208 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 209 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 210
 211 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 212 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 213 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 214 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 215 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 216 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 217 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 218 #define STATUS_GET_DATA(v)              ((v).data)
 219
 220 struct sbp2_status {
 221         u32 status;
 222         u32 orb_low;
 223         u8 data[24];
 224 };
 225
 226 struct sbp2_pointer {
 227         u32 high;
 228         u32 low;
 229 };
 230
 231 struct sbp2_orb {
 232         struct fw_transaction t;
 233         struct kref kref;
 234         dma_addr_t request_bus;
 235         int rcode;
 236         struct sbp2_pointer pointer;
 237         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 238         struct list_head link;
 239 };
 240
 241 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 242 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 243 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 244 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 245 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 246 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 247
 248 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 249 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 250
 251 struct sbp2_management_orb {
 252         struct sbp2_orb base;
 253         struct {
 254                 struct sbp2_pointer password;
 255                 struct sbp2_pointer response;
 256                 u32 misc;
 257                 u32 length;
 258                 struct sbp2_pointer status_fifo;
 259         } request;
 260         __be32 response[4];
 261         dma_addr_t response_bus;
 262         struct completion done;
 263         struct sbp2_status status;
 264 };
 265
 266 #define LOGIN_RESPONSE_GET_LOGIN_ID(v)  ((v).misc & 0xffff)
 267 #define LOGIN_RESPONSE_GET_LENGTH(v)    (((v).misc >> 16) & 0xffff)
 268
 269 struct sbp2_login_response {
 270         u32 misc;
 271         struct sbp2_pointer command_block_agent;
 272         u32 reconnect_hold;
 273 };
 274 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 275 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 276 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 277 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 278 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 279 #define COMMAND_ORB_DIRECTION(v)        ((v) << 27)
 280 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 281 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 282
 283 struct sbp2_command_orb {
 284         struct sbp2_orb base;
 285         struct {
 286                 struct sbp2_pointer next;
 287                 struct sbp2_pointer data_descriptor;
 288                 u32 misc;
 289                 u8 command_block[12];
 290         } request;
 291         struct scsi_cmnd *cmd;
 292         scsi_done_fn_t done;
 293         struct sbp2_logical_unit *lu;
 294
 295         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 296         dma_addr_t page_table_bus;
 297 };
 298
 299 /*
 300  * List of devices with known bugs.
 301  *
 302  * The firmware_revision field, masked with 0xffff00, is the best
 303  * indicator for the type of bridge chip of a device.  It yields a few
 304  * false positives but this did not break correctly behaving devices
 305  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
 306  * from the config rom can never match that.
 307  */
 308 static const struct {
 309         u32 firmware_revision;
 310         u32 model;
 311         unsigned int workarounds;
 312 } sbp2_workarounds_table[] = {
 313         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 314                 .firmware_revision      = 0x002800,
 315                 .model                  = 0x001010,
 316                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 317                                           SBP2_WORKAROUND_MODE_SENSE_8,
 318         },
 319         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 320                 .firmware_revision      = 0x002800,
 321                 .model                  = 0x000000,
 322                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY,
 323         },
 324         /* Initio bridges, actually only needed for some older ones */ {
 325                 .firmware_revision      = 0x000200,
 326                 .model                  = ~0,
 327                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 328         },
 329         /* Symbios bridge */ {
 330                 .firmware_revision      = 0xa0b800,
 331                 .model                  = ~0,
 332                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 333         },
 334         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 335                 .firmware_revision      = 0x002600,
 336                 .model                  = ~0,
 337                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 338         },
 339
 340         /*
 341          * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
 342          * these iPods do not feature the read_capacity bug according
 343          * to one report.  Read_capacity behaviour as well as model_id
 344          * could change due to Apple-supplied firmware updates though.
 345          */
 346
 347         /* iPod 4th generation. */ {
 348                 .firmware_revision      = 0x0a2700,
 349                 .model                  = 0x000021,
 350                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 351         },
 352         /* iPod mini */ {
 353                 .firmware_revision      = 0x0a2700,
 354                 .model                  = 0x000023,
 355                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 356         },
 357         /* iPod Photo */ {
 358                 .firmware_revision      = 0x0a2700,
 359                 .model                  = 0x00007e,
 360                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 361         }
 362 };
 363
 364 static void
 365 free_orb(struct kref *kref)
 366 {
 367         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 368
 369         kfree(orb);
 370 }
 371
 372 static void
 373 sbp2_status_write(struct fw_card *card, struct fw_request *request,
 374                   int tcode, int destination, int source,
 375                   int generation, int speed,
 376                   unsigned long long offset,
 377                   void *payload, size_t length, void *callback_data)
 378 {
 379         struct sbp2_logical_unit *lu = callback_data;
 380         struct sbp2_orb *orb;
 381         struct sbp2_status status;
 382         size_t header_size;
 383         unsigned long flags;
 384
 385         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 386             length == 0 || length > sizeof(status)) {
 387                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 388                 return;
 389         }
 390
 391         header_size = min(length, 2 * sizeof(u32));
 392         fw_memcpy_from_be32(&status, payload, header_size);
 393         if (length > header_size)
 394                 memcpy(status.data, payload + 8, length - header_size);
 395         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 396                 fw_notify("non-orb related status write, not handled\n");
 397                 fw_send_response(card, request, RCODE_COMPLETE);
 398                 return;
 399         }
 400
 401         /* Lookup the orb corresponding to this status write. */
 402         spin_lock_irqsave(&card->lock, flags);
 403         list_for_each_entry(orb, &lu->orb_list, link) {
 404                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 405                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 406                         orb->rcode = RCODE_COMPLETE;
 407                         list_del(&orb->link);
 408                         break;
 409                 }
 410         }
 411         spin_unlock_irqrestore(&card->lock, flags);
 412
 413         if (&orb->link != &lu->orb_list)
 414                 orb->callback(orb, &status);
 415         else
 416                 fw_error("status write for unknown orb\n");
 417
 418         kref_put(&orb->kref, free_orb);
 419
 420         fw_send_response(card, request, RCODE_COMPLETE);
 421 }
 422
 423 static void
 424 complete_transaction(struct fw_card *card, int rcode,
 425                      void *payload, size_t length, void *data)
 426 {
 427         struct sbp2_orb *orb = data;
 428         unsigned long flags;
 429
 430         /*
 431          * This is a little tricky.  We can get the status write for
 432          * the orb before we get this callback.  The status write
 433          * handler above will assume the orb pointer transaction was
 434          * successful and set the rcode to RCODE_COMPLETE for the orb.
 435          * So this callback only sets the rcode if it hasn't already
 436          * been set and only does the cleanup if the transaction
 437          * failed and we didn't already get a status write.
 438          */
 439         spin_lock_irqsave(&card->lock, flags);
 440
 441         if (orb->rcode == -1)
 442                 orb->rcode = rcode;
 443         if (orb->rcode != RCODE_COMPLETE) {
 444                 list_del(&orb->link);
 445                 spin_unlock_irqrestore(&card->lock, flags);
 446                 orb->callback(orb, NULL);
 447         } else {
 448                 spin_unlock_irqrestore(&card->lock, flags);
 449         }
 450
 451         kref_put(&orb->kref, free_orb);
 452 }
 453
 454 static void
 455 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 456               int node_id, int generation, u64 offset)
 457 {
 458         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 459         unsigned long flags;
 460
 461         orb->pointer.high = 0;
 462         orb->pointer.low = orb->request_bus;
 463         fw_memcpy_to_be32(&orb->pointer, &orb->pointer, sizeof(orb->pointer));
 464
 465         spin_lock_irqsave(&device->card->lock, flags);
 466         list_add_tail(&orb->link, &lu->orb_list);
 467         spin_unlock_irqrestore(&device->card->lock, flags);
 468
 469         /* Take a ref for the orb list and for the transaction callback. */
 470         kref_get(&orb->kref);
 471         kref_get(&orb->kref);
 472
 473         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 474                         node_id, generation, device->max_speed, offset,
 475                         &orb->pointer, sizeof(orb->pointer),
 476                         complete_transaction, orb);
 477 }
 478
 479 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 480 {
 481         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 482         struct sbp2_orb *orb, *next;
 483         struct list_head list;
 484         unsigned long flags;
 485         int retval = -ENOENT;
 486
 487         INIT_LIST_HEAD(&list);
 488         spin_lock_irqsave(&device->card->lock, flags);
 489         list_splice_init(&lu->orb_list, &list);
 490         spin_unlock_irqrestore(&device->card->lock, flags);
 491
 492         list_for_each_entry_safe(orb, next, &list, link) {
 493                 retval = 0;
 494                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 495                         continue;
 496
 497                 orb->rcode = RCODE_CANCELLED;
 498                 orb->callback(orb, NULL);
 499         }
 500
 501         return retval;
 502 }
 503
 504 static void
 505 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 506 {
 507         struct sbp2_management_orb *orb =
 508                 container_of(base_orb, struct sbp2_management_orb, base);
 509
 510         if (status)
 511                 memcpy(&orb->status, status, sizeof(*status));
 512         complete(&orb->done);
 513 }
 514
 515 static int
 516 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 517                          int generation, int function, int lun_or_login_id,
 518                          void *response)
 519 {
 520         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 521         struct sbp2_management_orb *orb;
 522         unsigned int timeout;
 523         int retval = -ENOMEM;
 524
 525         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 526                 return 0;
 527
 528         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 529         if (orb == NULL)
 530                 return -ENOMEM;
 531
 532         kref_init(&orb->base.kref);
 533         orb->response_bus =
 534                 dma_map_single(device->card->device, &orb->response,
 535                                sizeof(orb->response), DMA_FROM_DEVICE);
 536         if (dma_mapping_error(orb->response_bus))
 537                 goto fail_mapping_response;
 538
 539         orb->request.response.high    = 0;
 540         orb->request.response.low     = orb->response_bus;
 541
 542         orb->request.misc =
 543                 MANAGEMENT_ORB_NOTIFY |
 544                 MANAGEMENT_ORB_FUNCTION(function) |
 545                 MANAGEMENT_ORB_LUN(lun_or_login_id);
 546         orb->request.length =
 547                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response));
 548
 549         orb->request.status_fifo.high = lu->address_handler.offset >> 32;
 550         orb->request.status_fifo.low  = lu->address_handler.offset;
 551
 552         if (function == SBP2_LOGIN_REQUEST) {
 553                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 554                 orb->request.misc |=
 555                         MANAGEMENT_ORB_RECONNECT(2) |
 556                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login);
 557                 timeout = lu->tgt->mgt_orb_timeout;
 558         } else {
 559                 timeout = SBP2_ORB_TIMEOUT;
 560         }
 561
 562         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
 563
 564         init_completion(&orb->done);
 565         orb->base.callback = complete_management_orb;
 566
 567         orb->base.request_bus =
 568                 dma_map_single(device->card->device, &orb->request,
 569                                sizeof(orb->request), DMA_TO_DEVICE);
 570         if (dma_mapping_error(orb->base.request_bus))
 571                 goto fail_mapping_request;
 572
 573         sbp2_send_orb(&orb->base, lu, node_id, generation,
 574                       lu->tgt->management_agent_address);
 575
 576         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 577
 578         retval = -EIO;
 579         if (sbp2_cancel_orbs(lu) == 0) {
 580                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 581                          lu->tgt->bus_id, orb->base.rcode);
 582                 goto out;
 583         }
 584
 585         if (orb->base.rcode != RCODE_COMPLETE) {
 586                 fw_error("%s: management write failed, rcode 0x%02x\n",
 587                          lu->tgt->bus_id, orb->base.rcode);
 588                 goto out;
 589         }
 590
 591         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 592             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 593                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 594                          STATUS_GET_RESPONSE(orb->status),
 595                          STATUS_GET_SBP_STATUS(orb->status));
 596                 goto out;
 597         }
 598
 599         retval = 0;
 600  out:
 601         dma_unmap_single(device->card->device, orb->base.request_bus,
 602                          sizeof(orb->request), DMA_TO_DEVICE);
 603  fail_mapping_request:
 604         dma_unmap_single(device->card->device, orb->response_bus,
 605                          sizeof(orb->response), DMA_FROM_DEVICE);
 606  fail_mapping_response:
 607         if (response)
 608                 fw_memcpy_from_be32(response,
 609                                     orb->response, sizeof(orb->response));
 610         kref_put(&orb->base.kref, free_orb);
 611
 612         return retval;
 613 }
 614
 615 static void
 616 complete_agent_reset_write(struct fw_card *card, int rcode,
 617                            void *payload, size_t length, void *done)
 618 {
 619         complete(done);
 620 }
 621
 622 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 623 {
 624         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 625         DECLARE_COMPLETION_ONSTACK(done);
 626         struct fw_transaction t;
 627         static u32 z;
 628
 629         fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
 630                         lu->tgt->node_id, lu->generation, device->max_speed,
 631                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 632                         &z, sizeof(z), complete_agent_reset_write, &done);
 633         wait_for_completion(&done);
 634 }
 635
 636 static void
 637 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 638                                    void *payload, size_t length, void *data)
 639 {
 640         kfree(data);
 641 }
 642
 643 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 644 {
 645         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 646         struct fw_transaction *t;
 647         static u32 z;
 648
 649         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 650         if (t == NULL)
 651                 return;
 652
 653         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 654                         lu->tgt->node_id, lu->generation, device->max_speed,
 655                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 656                         &z, sizeof(z), complete_agent_reset_write_no_wait, t);
 657 }
 658
 659 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
 660 {
 661         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
 662         unsigned long flags;
 663
 664         /* serialize with comparisons of lu->generation and card->generation */
 665         spin_lock_irqsave(&card->lock, flags);
 666         lu->generation = generation;
 667         spin_unlock_irqrestore(&card->lock, flags);
 668 }
 669
 670 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 671 {
 672         /*
 673          * We may access dont_block without taking card->lock here:
 674          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 675          * are currently serialized against each other.
 676          * And a wrong result in sbp2_conditionally_block()'s access of
 677          * dont_block is rather harmless, it simply misses its first chance.
 678          */
 679         --lu->tgt->dont_block;
 680 }
 681
 682 /*
 683  * Blocks lu->tgt if all of the following conditions are met:
 684  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 685  *     logical units have been finished (indicated by dont_block == 0).
 686  *   - lu->generation is stale.
 687  *
 688  * Note, scsi_block_requests() must be called while holding card->lock,
 689  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 690  * unblock the target.
 691  */
 692 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 693 {
 694         struct sbp2_target *tgt = lu->tgt;
 695         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 696         struct Scsi_Host *shost =
 697                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 698         unsigned long flags;
 699
 700         spin_lock_irqsave(&card->lock, flags);
 701         if (!tgt->dont_block && !lu->blocked &&
 702             lu->generation != card->generation) {
 703                 lu->blocked = true;
 704                 if (++tgt->blocked == 1) {
 705                         scsi_block_requests(shost);
 706                         fw_notify("blocked %s\n", lu->tgt->bus_id);
 707                 }
 708         }
 709         spin_unlock_irqrestore(&card->lock, flags);
 710 }
 711
 712 /*
 713  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 714  * Note, it is harmless to run scsi_unblock_requests() outside the
 715  * card->lock protected section.  On the other hand, running it inside
 716  * the section might clash with shost->host_lock.
 717  */
 718 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 719 {
 720         struct sbp2_target *tgt = lu->tgt;
 721         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 722         struct Scsi_Host *shost =
 723                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 724         unsigned long flags;
 725         bool unblock = false;
 726
 727         spin_lock_irqsave(&card->lock, flags);
 728         if (lu->blocked && lu->generation == card->generation) {
 729                 lu->blocked = false;
 730                 unblock = --tgt->blocked == 0;
 731         }
 732         spin_unlock_irqrestore(&card->lock, flags);
 733
 734         if (unblock) {
 735                 scsi_unblock_requests(shost);
 736                 fw_notify("unblocked %s\n", lu->tgt->bus_id);
 737         }
 738 }
 739
 740 /*
 741  * Prevents future blocking of tgt and unblocks it.
 742  * Note, it is harmless to run scsi_unblock_requests() outside the
 743  * card->lock protected section.  On the other hand, running it inside
 744  * the section might clash with shost->host_lock.
 745  */
 746 static void sbp2_unblock(struct sbp2_target *tgt)
 747 {
 748         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 749         struct Scsi_Host *shost =
 750                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 751         unsigned long flags;
 752
 753         spin_lock_irqsave(&card->lock, flags);
 754         ++tgt->dont_block;
 755         spin_unlock_irqrestore(&card->lock, flags);
 756
 757         scsi_unblock_requests(shost);
 758 }
 759
 760 static int sbp2_lun2int(u16 lun)
 761 {
 762         struct scsi_lun eight_bytes_lun;
 763
 764         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 765         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 766         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 767
 768         return scsilun_to_int(&eight_bytes_lun);
 769 }
 770
 771 static void sbp2_release_target(struct kref *kref)
 772 {
 773         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 774         struct sbp2_logical_unit *lu, *next;
 775         struct Scsi_Host *shost =
 776                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 777         struct scsi_device *sdev;
 778         struct fw_device *device = fw_device(tgt->unit->device.parent);
 779
 780         /* prevent deadlocks */
 781         sbp2_unblock(tgt);
 782
 783         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 784                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 785                 if (sdev) {
 786                         scsi_remove_device(sdev);
 787                         scsi_device_put(sdev);
 788                 }
 789                 sbp2_send_management_orb(lu, tgt->node_id, lu->generation,
 790                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 791
 792                 fw_core_remove_address_handler(&lu->address_handler);
 793                 list_del(&lu->link);
 794                 kfree(lu);
 795         }
 796         scsi_remove_host(shost);
 797         fw_notify("released %s\n", tgt->bus_id);
 798
 799         put_device(&tgt->unit->device);
 800         scsi_host_put(shost);
 801         fw_device_put(device);
 802 }
 803
 804 static struct workqueue_struct *sbp2_wq;
 805
 806 /*
 807  * Always get the target's kref when scheduling work on one its units.
 808  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 809  */
 810 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 811 {
 812         if (queue_delayed_work(sbp2_wq, &lu->work, delay))
 813                 kref_get(&lu->tgt->kref);
 814 }
 815
 816 static void sbp2_target_put(struct sbp2_target *tgt)
 817 {
 818         kref_put(&tgt->kref, sbp2_release_target);
 819 }
 820
 821 static void
 822 complete_set_busy_timeout(struct fw_card *card, int rcode,
 823                           void *payload, size_t length, void *done)
 824 {
 825         complete(done);
 826 }
 827
 828 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 829 {
 830         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 831         DECLARE_COMPLETION_ONSTACK(done);
 832         struct fw_transaction t;
 833         static __be32 busy_timeout;
 834
 835         /* FIXME: we should try to set dual-phase cycle_limit too */
 836         busy_timeout = cpu_to_be32(SBP2_RETRY_LIMIT);
 837
 838         fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
 839                         lu->tgt->node_id, lu->generation, device->max_speed,
 840                         CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &busy_timeout,
 841                         sizeof(busy_timeout), complete_set_busy_timeout, &done);
 842         wait_for_completion(&done);
 843 }
 844
 845 static void sbp2_reconnect(struct work_struct *work);
 846
 847 static void sbp2_login(struct work_struct *work)
 848 {
 849         struct sbp2_logical_unit *lu =
 850                 container_of(work, struct sbp2_logical_unit, work.work);
 851         struct sbp2_target *tgt = lu->tgt;
 852         struct fw_device *device = fw_device(tgt->unit->device.parent);
 853         struct Scsi_Host *shost;
 854         struct scsi_device *sdev;
 855         struct sbp2_login_response response;
 856         int generation, node_id, local_node_id;
 857
 858         if (fw_device_is_shutdown(device))
 859                 goto out;
 860
 861         generation    = device->generation;
 862         smp_rmb();    /* node_id must not be older than generation */
 863         node_id       = device->node_id;
 864         local_node_id = device->card->node_id;
 865
 866         /* If this is a re-login attempt, log out, or we might be rejected. */
 867         if (lu->has_sdev)
 868                 sbp2_send_management_orb(lu, device->node_id, generation,
 869                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 870
 871         if (sbp2_send_management_orb(lu, node_id, generation,
 872                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 873                 if (lu->retries++ < 5) {
 874                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 875                 } else {
 876                         fw_error("%s: failed to login to LUN %04x\n",
 877                                  tgt->bus_id, lu->lun);
 878                         /* Let any waiting I/O fail from now on. */
 879                         sbp2_unblock(lu->tgt);
 880                 }
 881                 goto out;
 882         }
 883
 884         tgt->node_id      = node_id;
 885         tgt->address_high = local_node_id << 16;
 886         sbp2_set_generation(lu, generation);
 887
 888         /* Get command block agent offset and login id. */
 889         lu->command_block_agent_address =
 890                 ((u64) (response.command_block_agent.high & 0xffff) << 32) |
 891                 response.command_block_agent.low;
 892         lu->login_id = LOGIN_RESPONSE_GET_LOGIN_ID(response);
 893
 894         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 895                   tgt->bus_id, lu->lun, lu->retries);
 896
 897         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 898         sbp2_set_busy_timeout(lu);
 899
 900         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 901         sbp2_agent_reset(lu);
 902
 903         /* This was a re-login. */
 904         if (lu->has_sdev) {
 905                 sbp2_cancel_orbs(lu);
 906                 sbp2_conditionally_unblock(lu);
 907                 goto out;
 908         }
 909
 910         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 911                 ssleep(SBP2_INQUIRY_DELAY);
 912
 913         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 914         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 915         /*
 916          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 917          * Therefore __scsi_add_device() will get into trouble if a bus reset
 918          * happens in parallel.  It will either fail or leave us with an
 919          * unusable sdev.  As a workaround we check for this and retry the
 920          * whole login and SCSI probing.
 921          */
 922
 923         /* Reported error during __scsi_add_device() */
 924         if (IS_ERR(sdev))
 925                 goto out_logout_login;
 926
 927         /* Unreported error during __scsi_add_device() */
 928         smp_rmb(); /* get current card generation */
 929         if (generation != device->card->generation) {
 930                 scsi_remove_device(sdev);
 931                 scsi_device_put(sdev);
 932                 goto out_logout_login;
 933         }
 934
 935         /* No error during __scsi_add_device() */
 936         lu->has_sdev = true;
 937         scsi_device_put(sdev);
 938         sbp2_allow_block(lu);
 939         goto out;
 940
 941  out_logout_login:
 942         smp_rmb(); /* generation may have changed */
 943         generation = device->generation;
 944         smp_rmb(); /* node_id must not be older than generation */
 945
 946         sbp2_send_management_orb(lu, device->node_id, generation,
 947                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 948         /*
 949          * If a bus reset happened, sbp2_update will have requeued
 950          * lu->work already.  Reset the work from reconnect to login.
 951          */
 952         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 953  out:
 954         sbp2_target_put(tgt);
 955 }
 956
 957 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 958 {
 959         struct sbp2_logical_unit *lu;
 960
 961         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 962         if (!lu)
 963                 return -ENOMEM;
 964
 965         lu->address_handler.length           = 0x100;
 966         lu->address_handler.address_callback = sbp2_status_write;
 967         lu->address_handler.callback_data    = lu;
 968
 969         if (fw_core_add_address_handler(&lu->address_handler,
 970                                         &fw_high_memory_region) < 0) {
 971                 kfree(lu);
 972                 return -ENOMEM;
 973         }
 974
 975         lu->tgt      = tgt;
 976         lu->lun      = lun_entry & 0xffff;
 977         lu->retries  = 0;
 978         lu->has_sdev = false;
 979         lu->blocked  = false;
 980         ++tgt->dont_block;
 981         INIT_LIST_HEAD(&lu->orb_list);
 982         INIT_DELAYED_WORK(&lu->work, sbp2_login);
 983
 984         list_add_tail(&lu->link, &tgt->lu_list);
 985         return 0;
 986 }
 987
 988 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
 989 {
 990         struct fw_csr_iterator ci;
 991         int key, value;
 992
 993         fw_csr_iterator_init(&ci, directory);
 994         while (fw_csr_iterator_next(&ci, &key, &value))
 995                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
 996                     sbp2_add_logical_unit(tgt, value) < 0)
 997                         return -ENOMEM;
 998         return 0;
 999 }
1000
1001 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
1002                               u32 *model, u32 *firmware_revision)
1003 {
1004         struct fw_csr_iterator ci;
1005         int key, value;
1006         unsigned int timeout;
1007
1008         fw_csr_iterator_init(&ci, directory);
1009         while (fw_csr_iterator_next(&ci, &key, &value)) {
1010                 switch (key) {
1011
1012                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1013                         tgt->management_agent_address =
1014                                         CSR_REGISTER_BASE + 4 * value;
1015                         break;
1016
1017                 case CSR_DIRECTORY_ID:
1018                         tgt->directory_id = value;
1019                         break;
1020
1021                 case CSR_MODEL:
1022                         *model = value;
1023                         break;
1024
1025                 case SBP2_CSR_FIRMWARE_REVISION:
1026                         *firmware_revision = value;
1027                         break;
1028
1029                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1030                         /* the timeout value is stored in 500ms units */
1031                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1032                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1033                         tgt->mgt_orb_timeout =
1034                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1035
1036                         if (timeout > tgt->mgt_orb_timeout)
1037                                 fw_notify("%s: config rom contains %ds "
1038                                           "management ORB timeout, limiting "
1039                                           "to %ds\n", tgt->bus_id,
1040                                           timeout / 1000,
1041                                           tgt->mgt_orb_timeout / 1000);
1042                         break;
1043
1044                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1045                         if (sbp2_add_logical_unit(tgt, value) < 0)
1046                                 return -ENOMEM;
1047                         break;
1048
1049                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1050                         if (sbp2_scan_logical_unit_dir(tgt, ci.p + value) < 0)
1051                                 return -ENOMEM;
1052                         break;
1053                 }
1054         }
1055         return 0;
1056 }
1057
1058 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1059                                   u32 firmware_revision)
1060 {
1061         int i;
1062         unsigned int w = sbp2_param_workarounds;
1063
1064         if (w)
1065                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1066                           "if you need the workarounds parameter for %s\n",
1067                           tgt->bus_id);
1068
1069         if (w & SBP2_WORKAROUND_OVERRIDE)
1070                 goto out;
1071
1072         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1073
1074                 if (sbp2_workarounds_table[i].firmware_revision !=
1075                     (firmware_revision & 0xffffff00))
1076                         continue;
1077
1078                 if (sbp2_workarounds_table[i].model != model &&
1079                     sbp2_workarounds_table[i].model != ~0)
1080                         continue;
1081
1082                 w |= sbp2_workarounds_table[i].workarounds;
1083                 break;
1084         }
1085  out:
1086         if (w)
1087                 fw_notify("Workarounds for %s: 0x%x "
1088                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1089                           tgt->bus_id, w, firmware_revision, model);
1090         tgt->workarounds = w;
1091 }
1092
1093 static struct scsi_host_template scsi_driver_template;
1094
1095 static int sbp2_probe(struct device *dev)
1096 {
1097         struct fw_unit *unit = fw_unit(dev);
1098         struct fw_device *device = fw_device(unit->device.parent);
1099         struct sbp2_target *tgt;
1100         struct sbp2_logical_unit *lu;
1101         struct Scsi_Host *shost;
1102         u32 model, firmware_revision;
1103
1104         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1105         if (shost == NULL)
1106                 return -ENOMEM;
1107
1108         tgt = (struct sbp2_target *)shost->hostdata;
1109         unit->device.driver_data = tgt;
1110         tgt->unit = unit;
1111         kref_init(&tgt->kref);
1112         INIT_LIST_HEAD(&tgt->lu_list);
1113         tgt->bus_id = unit->device.bus_id;
1114
1115         if (fw_device_enable_phys_dma(device) < 0)
1116                 goto fail_shost_put;
1117
1118         if (scsi_add_host(shost, &unit->device) < 0)
1119                 goto fail_shost_put;
1120
1121         fw_device_get(device);
1122
1123         /* Initialize to values that won't match anything in our table. */
1124         firmware_revision = 0xff000000;
1125         model = 0xff000000;
1126
1127         /* implicit directory ID */
1128         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1129                              + CSR_CONFIG_ROM) & 0xffffff;
1130
1131         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1132                                &firmware_revision) < 0)
1133                 goto fail_tgt_put;
1134
1135         sbp2_init_workarounds(tgt, model, firmware_revision);
1136
1137         get_device(&unit->device);
1138
1139         /* Do the login in a workqueue so we can easily reschedule retries. */
1140         list_for_each_entry(lu, &tgt->lu_list, link)
1141                 sbp2_queue_work(lu, 0);
1142         return 0;
1143
1144  fail_tgt_put:
1145         sbp2_target_put(tgt);
1146         return -ENOMEM;
1147
1148  fail_shost_put:
1149         scsi_host_put(shost);
1150         return -ENOMEM;
1151 }
1152
1153 static int sbp2_remove(struct device *dev)
1154 {
1155         struct fw_unit *unit = fw_unit(dev);
1156         struct sbp2_target *tgt = unit->device.driver_data;
1157
1158         sbp2_target_put(tgt);
1159         return 0;
1160 }
1161
1162 static void sbp2_reconnect(struct work_struct *work)
1163 {
1164         struct sbp2_logical_unit *lu =
1165                 container_of(work, struct sbp2_logical_unit, work.work);
1166         struct sbp2_target *tgt = lu->tgt;
1167         struct fw_device *device = fw_device(tgt->unit->device.parent);
1168         int generation, node_id, local_node_id;
1169
1170         if (fw_device_is_shutdown(device))
1171                 goto out;
1172
1173         generation    = device->generation;
1174         smp_rmb();    /* node_id must not be older than generation */
1175         node_id       = device->node_id;
1176         local_node_id = device->card->node_id;
1177
1178         if (sbp2_send_management_orb(lu, node_id, generation,
1179                                      SBP2_RECONNECT_REQUEST,
1180                                      lu->login_id, NULL) < 0) {
1181                 /*
1182                  * If reconnect was impossible even though we are in the
1183                  * current generation, fall back and try to log in again.
1184                  *
1185                  * We could check for "Function rejected" status, but
1186                  * looking at the bus generation as simpler and more general.
1187                  */
1188                 smp_rmb(); /* get current card generation */
1189                 if (generation == device->card->generation ||
1190                     lu->retries++ >= 5) {
1191                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1192                         lu->retries = 0;
1193                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1194                 }
1195                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1196                 goto out;
1197         }
1198
1199         tgt->node_id      = node_id;
1200         tgt->address_high = local_node_id << 16;
1201         sbp2_set_generation(lu, generation);
1202
1203         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1204                   tgt->bus_id, lu->lun, lu->retries);
1205
1206         sbp2_agent_reset(lu);
1207         sbp2_cancel_orbs(lu);
1208         sbp2_conditionally_unblock(lu);
1209  out:
1210         sbp2_target_put(tgt);
1211 }
1212
1213 static void sbp2_update(struct fw_unit *unit)
1214 {
1215         struct sbp2_target *tgt = unit->device.driver_data;
1216         struct sbp2_logical_unit *lu;
1217
1218         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1219
1220         /*
1221          * Fw-core serializes sbp2_update() against sbp2_remove().
1222          * Iteration over tgt->lu_list is therefore safe here.
1223          */
1224         list_for_each_entry(lu, &tgt->lu_list, link) {
1225                 sbp2_conditionally_block(lu);
1226                 lu->retries = 0;
1227                 sbp2_queue_work(lu, 0);
1228         }
1229 }
1230
1231 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1232 #define SBP2_SW_VERSION_ENTRY   0x00010483
1233
1234 static const struct fw_device_id sbp2_id_table[] = {
1235         {
1236                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1237                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1238                 .version      = SBP2_SW_VERSION_ENTRY,
1239         },
1240         { }
1241 };
1242
1243 static struct fw_driver sbp2_driver = {
1244         .driver   = {
1245                 .owner  = THIS_MODULE,
1246                 .name   = sbp2_driver_name,
1247                 .bus    = &fw_bus_type,
1248                 .probe  = sbp2_probe,
1249                 .remove = sbp2_remove,
1250         },
1251         .update   = sbp2_update,
1252         .id_table = sbp2_id_table,
1253 };
1254
1255 static unsigned int
1256 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1257 {
1258         int sam_status;
1259
1260         sense_data[0] = 0x70;
1261         sense_data[1] = 0x0;
1262         sense_data[2] = sbp2_status[1];
1263         sense_data[3] = sbp2_status[4];
1264         sense_data[4] = sbp2_status[5];
1265         sense_data[5] = sbp2_status[6];
1266         sense_data[6] = sbp2_status[7];
1267         sense_data[7] = 10;
1268         sense_data[8] = sbp2_status[8];
1269         sense_data[9] = sbp2_status[9];
1270         sense_data[10] = sbp2_status[10];
1271         sense_data[11] = sbp2_status[11];
1272         sense_data[12] = sbp2_status[2];
1273         sense_data[13] = sbp2_status[3];
1274         sense_data[14] = sbp2_status[12];
1275         sense_data[15] = sbp2_status[13];
1276
1277         sam_status = sbp2_status[0] & 0x3f;
1278
1279         switch (sam_status) {
1280         case SAM_STAT_GOOD:
1281         case SAM_STAT_CHECK_CONDITION:
1282         case SAM_STAT_CONDITION_MET:
1283         case SAM_STAT_BUSY:
1284         case SAM_STAT_RESERVATION_CONFLICT:
1285         case SAM_STAT_COMMAND_TERMINATED:
1286                 return DID_OK << 16 | sam_status;
1287
1288         default:
1289                 return DID_ERROR << 16;
1290         }
1291 }
1292
1293 static void
1294 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1295 {
1296         struct sbp2_command_orb *orb =
1297                 container_of(base_orb, struct sbp2_command_orb, base);
1298         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1299         int result;
1300
1301         if (status != NULL) {
1302                 if (STATUS_GET_DEAD(*status))
1303                         sbp2_agent_reset_no_wait(orb->lu);
1304
1305                 switch (STATUS_GET_RESPONSE(*status)) {
1306                 case SBP2_STATUS_REQUEST_COMPLETE:
1307                         result = DID_OK << 16;
1308                         break;
1309                 case SBP2_STATUS_TRANSPORT_FAILURE:
1310                         result = DID_BUS_BUSY << 16;
1311                         break;
1312                 case SBP2_STATUS_ILLEGAL_REQUEST:
1313                 case SBP2_STATUS_VENDOR_DEPENDENT:
1314                 default:
1315                         result = DID_ERROR << 16;
1316                         break;
1317                 }
1318
1319                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1320                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1321                                                            orb->cmd->sense_buffer);
1322         } else {
1323                 /*
1324                  * If the orb completes with status == NULL, something
1325                  * went wrong, typically a bus reset happened mid-orb
1326                  * or when sending the write (less likely).
1327                  */
1328                 result = DID_BUS_BUSY << 16;
1329                 sbp2_conditionally_block(orb->lu);
1330         }
1331
1332         dma_unmap_single(device->card->device, orb->base.request_bus,
1333                          sizeof(orb->request), DMA_TO_DEVICE);
1334
1335         if (scsi_sg_count(orb->cmd) > 0)
1336                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1337                              scsi_sg_count(orb->cmd),
1338                              orb->cmd->sc_data_direction);
1339
1340         if (orb->page_table_bus != 0)
1341                 dma_unmap_single(device->card->device, orb->page_table_bus,
1342                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1343
1344         orb->cmd->result = result;
1345         orb->done(orb->cmd);
1346 }
1347
1348 static int
1349 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1350                      struct sbp2_logical_unit *lu)
1351 {
1352         struct scatterlist *sg;
1353         int sg_len, l, i, j, count;
1354         dma_addr_t sg_addr;
1355
1356         sg = scsi_sglist(orb->cmd);
1357         count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1358                            orb->cmd->sc_data_direction);
1359         if (count == 0)
1360                 goto fail;
1361
1362         /*
1363          * Handle the special case where there is only one element in
1364          * the scatter list by converting it to an immediate block
1365          * request. This is also a workaround for broken devices such
1366          * as the second generation iPod which doesn't support page
1367          * tables.
1368          */
1369         if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) {
1370                 orb->request.data_descriptor.high = lu->tgt->address_high;
1371                 orb->request.data_descriptor.low  = sg_dma_address(sg);
1372                 orb->request.misc |= COMMAND_ORB_DATA_SIZE(sg_dma_len(sg));
1373                 return 0;
1374         }
1375
1376         /*
1377          * Convert the scatterlist to an sbp2 page table.  If any
1378          * scatterlist entries are too big for sbp2, we split them as we
1379          * go.  Even if we ask the block I/O layer to not give us sg
1380          * elements larger than 65535 bytes, some IOMMUs may merge sg elements
1381          * during DMA mapping, and Linux currently doesn't prevent this.
1382          */
1383         for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) {
1384                 sg_len = sg_dma_len(sg);
1385                 sg_addr = sg_dma_address(sg);
1386                 while (sg_len) {
1387                         /* FIXME: This won't get us out of the pinch. */
1388                         if (unlikely(j >= ARRAY_SIZE(orb->page_table))) {
1389                                 fw_error("page table overflow\n");
1390                                 goto fail_page_table;
1391                         }
1392                         l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH);
1393                         orb->page_table[j].low = sg_addr;
1394                         orb->page_table[j].high = (l << 16);
1395                         sg_addr += l;
1396                         sg_len -= l;
1397                         j++;
1398                 }
1399         }
1400
1401         fw_memcpy_to_be32(orb->page_table, orb->page_table,
1402                           sizeof(orb->page_table[0]) * j);
1403         orb->page_table_bus =
1404                 dma_map_single(device->card->device, orb->page_table,
1405                                sizeof(orb->page_table), DMA_TO_DEVICE);
1406         if (dma_mapping_error(orb->page_table_bus))
1407                 goto fail_page_table;
1408
1409         /*
1410          * The data_descriptor pointer is the one case where we need
1411          * to fill in the node ID part of the address.  All other
1412          * pointers assume that the data referenced reside on the
1413          * initiator (i.e. us), but data_descriptor can refer to data
1414          * on other nodes so we need to put our ID in descriptor.high.
1415          */
1416         orb->request.data_descriptor.high = lu->tgt->address_high;
1417         orb->request.data_descriptor.low  = orb->page_table_bus;
1418         orb->request.misc |=
1419                 COMMAND_ORB_PAGE_TABLE_PRESENT |
1420                 COMMAND_ORB_DATA_SIZE(j);
1421
1422         return 0;
1423
1424  fail_page_table:
1425         dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1426                      orb->cmd->sc_data_direction);
1427  fail:
1428         return -ENOMEM;
1429 }
1430
1431 /* SCSI stack integration */
1432
1433 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1434 {
1435         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1436         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1437         struct sbp2_command_orb *orb;
1438         unsigned int max_payload;
1439         int retval = SCSI_MLQUEUE_HOST_BUSY;
1440
1441         /*
1442          * Bidirectional commands are not yet implemented, and unknown
1443          * transfer direction not handled.
1444          */
1445         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1446                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1447                 cmd->result = DID_ERROR << 16;
1448                 done(cmd);
1449                 return 0;
1450         }
1451
1452         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1453         if (orb == NULL) {
1454                 fw_notify("failed to alloc orb\n");
1455                 return SCSI_MLQUEUE_HOST_BUSY;
1456         }
1457
1458         /* Initialize rcode to something not RCODE_COMPLETE. */
1459         orb->base.rcode = -1;
1460         kref_init(&orb->base.kref);
1461
1462         orb->lu   = lu;
1463         orb->done = done;
1464         orb->cmd  = cmd;
1465
1466         orb->request.next.high   = SBP2_ORB_NULL;
1467         orb->request.next.low    = 0x0;
1468         /*
1469          * At speed 100 we can do 512 bytes per packet, at speed 200,
1470          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1471          * specifies the max payload size as 2 ^ (max_payload + 2), so
1472          * if we set this to max_speed + 7, we get the right value.
1473          */
1474         max_payload = min(device->max_speed + 7,
1475                           device->card->max_receive - 1);
1476         orb->request.misc =
1477                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1478                 COMMAND_ORB_SPEED(device->max_speed) |
1479                 COMMAND_ORB_NOTIFY;
1480
1481         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1482                 orb->request.misc |=
1483                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_FROM_MEDIA);
1484         else if (cmd->sc_data_direction == DMA_TO_DEVICE)
1485                 orb->request.misc |=
1486                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_TO_MEDIA);
1487
1488         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1489                 goto out;
1490
1491         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
1492
1493         memset(orb->request.command_block,
1494                0, sizeof(orb->request.command_block));
1495         memcpy(orb->request.command_block, cmd->cmnd, COMMAND_SIZE(*cmd->cmnd));
1496
1497         orb->base.callback = complete_command_orb;
1498         orb->base.request_bus =
1499                 dma_map_single(device->card->device, &orb->request,
1500                                sizeof(orb->request), DMA_TO_DEVICE);
1501         if (dma_mapping_error(orb->base.request_bus))
1502                 goto out;
1503
1504         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, lu->generation,
1505                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1506         retval = 0;
1507  out:
1508         kref_put(&orb->base.kref, free_orb);
1509         return retval;
1510 }
1511
1512 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1513 {
1514         struct sbp2_logical_unit *lu = sdev->hostdata;
1515
1516         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1517         if (!lu)
1518                 return -ENOSYS;
1519
1520         sdev->allow_restart = 1;
1521
1522         /*
1523          * Update the dma alignment (minimum alignment requirements for
1524          * start and end of DMA transfers) to be a sector
1525          */
1526         blk_queue_update_dma_alignment(sdev->request_queue, 511);
1527
1528         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1529                 sdev->inquiry_len = 36;
1530
1531         return 0;
1532 }
1533
1534 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1535 {
1536         struct sbp2_logical_unit *lu = sdev->hostdata;
1537
1538         sdev->use_10_for_rw = 1;
1539
1540         if (sdev->type == TYPE_ROM)
1541                 sdev->use_10_for_ms = 1;
1542
1543         if (sdev->type == TYPE_DISK &&
1544             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1545                 sdev->skip_ms_page_8 = 1;
1546
1547         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1548                 sdev->fix_capacity = 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         return 0;
1554 }
1555
1556 /*
1557  * Called by scsi stack when something has really gone wrong.  Usually
1558  * called when a command has timed-out for some reason.
1559  */
1560 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1561 {
1562         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1563
1564         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1565         sbp2_agent_reset(lu);
1566         sbp2_cancel_orbs(lu);
1567
1568         return SUCCESS;
1569 }
1570
1571 /*
1572  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1573  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1574  *
1575  * This is the concatenation of target port identifier and logical unit
1576  * identifier as per SAM-2...SAM-4 annex A.
1577  */
1578 static ssize_t
1579 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1580                             char *buf)
1581 {
1582         struct scsi_device *sdev = to_scsi_device(dev);
1583         struct sbp2_logical_unit *lu;
1584         struct fw_device *device;
1585
1586         if (!sdev)
1587                 return 0;
1588
1589         lu = sdev->hostdata;
1590         device = fw_device(lu->tgt->unit->device.parent);
1591
1592         return sprintf(buf, "%08x%08x:%06x:%04x\n",
1593                         device->config_rom[3], device->config_rom[4],
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);