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 /* Unit directory keys */
 179 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 180 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 181 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 182 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 183
 184 /* Management orb opcodes */
 185 #define SBP2_LOGIN_REQUEST              0x0
 186 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 187 #define SBP2_RECONNECT_REQUEST          0x3
 188 #define SBP2_SET_PASSWORD_REQUEST       0x4
 189 #define SBP2_LOGOUT_REQUEST             0x7
 190 #define SBP2_ABORT_TASK_REQUEST         0xb
 191 #define SBP2_ABORT_TASK_SET             0xc
 192 #define SBP2_LOGICAL_UNIT_RESET         0xe
 193 #define SBP2_TARGET_RESET_REQUEST       0xf
 194
 195 /* Offsets for command block agent registers */
 196 #define SBP2_AGENT_STATE                0x00
 197 #define SBP2_AGENT_RESET                0x04
 198 #define SBP2_ORB_POINTER                0x08
 199 #define SBP2_DOORBELL                   0x10
 200 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 201
 202 /* Status write response codes */
 203 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 204 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 205 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 206 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 207
 208 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 209 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 210 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 211 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 212 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 213 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 214 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 215 #define STATUS_GET_DATA(v)              ((v).data)
 216
 217 struct sbp2_status {
 218         u32 status;
 219         u32 orb_low;
 220         u8 data[24];
 221 };
 222
 223 struct sbp2_pointer {
 224         __be32 high;
 225         __be32 low;
 226 };
 227
 228 struct sbp2_orb {
 229         struct fw_transaction t;
 230         struct kref kref;
 231         dma_addr_t request_bus;
 232         int rcode;
 233         struct sbp2_pointer pointer;
 234         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 235         struct list_head link;
 236 };
 237
 238 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 239 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 240 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 241 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 242 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 243 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 244
 245 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 246 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 247
 248 struct sbp2_management_orb {
 249         struct sbp2_orb base;
 250         struct {
 251                 struct sbp2_pointer password;
 252                 struct sbp2_pointer response;
 253                 __be32 misc;
 254                 __be32 length;
 255                 struct sbp2_pointer status_fifo;
 256         } request;
 257         __be32 response[4];
 258         dma_addr_t response_bus;
 259         struct completion done;
 260         struct sbp2_status status;
 261 };
 262
 263 struct sbp2_login_response {
 264         __be32 misc;
 265         struct sbp2_pointer command_block_agent;
 266         __be32 reconnect_hold;
 267 };
 268 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 269 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 270 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 271 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 272 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 273 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 274 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 275 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 276
 277 struct sbp2_command_orb {
 278         struct sbp2_orb base;
 279         struct {
 280                 struct sbp2_pointer next;
 281                 struct sbp2_pointer data_descriptor;
 282                 __be32 misc;
 283                 u8 command_block[12];
 284         } request;
 285         struct scsi_cmnd *cmd;
 286         scsi_done_fn_t done;
 287         struct sbp2_logical_unit *lu;
 288
 289         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 290         dma_addr_t page_table_bus;
 291 };
 292
 293 /*
 294  * List of devices with known bugs.
 295  *
 296  * The firmware_revision field, masked with 0xffff00, is the best
 297  * indicator for the type of bridge chip of a device.  It yields a few
 298  * false positives but this did not break correctly behaving devices
 299  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
 300  * from the config rom can never match that.
 301  */
 302 static const struct {
 303         u32 firmware_revision;
 304         u32 model;
 305         unsigned int workarounds;
 306 } sbp2_workarounds_table[] = {
 307         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 308                 .firmware_revision      = 0x002800,
 309                 .model                  = 0x001010,
 310                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 311                                           SBP2_WORKAROUND_MODE_SENSE_8,
 312         },
 313         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 314                 .firmware_revision      = 0x002800,
 315                 .model                  = 0x000000,
 316                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY,
 317         },
 318         /* Initio bridges, actually only needed for some older ones */ {
 319                 .firmware_revision      = 0x000200,
 320                 .model                  = ~0,
 321                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 322         },
 323         /* Symbios bridge */ {
 324                 .firmware_revision      = 0xa0b800,
 325                 .model                  = ~0,
 326                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 327         },
 328         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 329                 .firmware_revision      = 0x002600,
 330                 .model                  = ~0,
 331                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 332         },
 333
 334         /*
 335          * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
 336          * these iPods do not feature the read_capacity bug according
 337          * to one report.  Read_capacity behaviour as well as model_id
 338          * could change due to Apple-supplied firmware updates though.
 339          */
 340
 341         /* iPod 4th generation. */ {
 342                 .firmware_revision      = 0x0a2700,
 343                 .model                  = 0x000021,
 344                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 345         },
 346         /* iPod mini */ {
 347                 .firmware_revision      = 0x0a2700,
 348                 .model                  = 0x000023,
 349                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 350         },
 351         /* iPod Photo */ {
 352                 .firmware_revision      = 0x0a2700,
 353                 .model                  = 0x00007e,
 354                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 355         }
 356 };
 357
 358 static void
 359 free_orb(struct kref *kref)
 360 {
 361         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 362
 363         kfree(orb);
 364 }
 365
 366 static void
 367 sbp2_status_write(struct fw_card *card, struct fw_request *request,
 368                   int tcode, int destination, int source,
 369                   int generation, int speed,
 370                   unsigned long long offset,
 371                   void *payload, size_t length, void *callback_data)
 372 {
 373         struct sbp2_logical_unit *lu = callback_data;
 374         struct sbp2_orb *orb;
 375         struct sbp2_status status;
 376         size_t header_size;
 377         unsigned long flags;
 378
 379         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 380             length == 0 || length > sizeof(status)) {
 381                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 382                 return;
 383         }
 384
 385         header_size = min(length, 2 * sizeof(u32));
 386         fw_memcpy_from_be32(&status, payload, header_size);
 387         if (length > header_size)
 388                 memcpy(status.data, payload + 8, length - header_size);
 389         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 390                 fw_notify("non-orb related status write, not handled\n");
 391                 fw_send_response(card, request, RCODE_COMPLETE);
 392                 return;
 393         }
 394
 395         /* Lookup the orb corresponding to this status write. */
 396         spin_lock_irqsave(&card->lock, flags);
 397         list_for_each_entry(orb, &lu->orb_list, link) {
 398                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 399                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 400                         orb->rcode = RCODE_COMPLETE;
 401                         list_del(&orb->link);
 402                         break;
 403                 }
 404         }
 405         spin_unlock_irqrestore(&card->lock, flags);
 406
 407         if (&orb->link != &lu->orb_list)
 408                 orb->callback(orb, &status);
 409         else
 410                 fw_error("status write for unknown orb\n");
 411
 412         kref_put(&orb->kref, free_orb);
 413
 414         fw_send_response(card, request, RCODE_COMPLETE);
 415 }
 416
 417 static void
 418 complete_transaction(struct fw_card *card, int rcode,
 419                      void *payload, size_t length, void *data)
 420 {
 421         struct sbp2_orb *orb = data;
 422         unsigned long flags;
 423
 424         /*
 425          * This is a little tricky.  We can get the status write for
 426          * the orb before we get this callback.  The status write
 427          * handler above will assume the orb pointer transaction was
 428          * successful and set the rcode to RCODE_COMPLETE for the orb.
 429          * So this callback only sets the rcode if it hasn't already
 430          * been set and only does the cleanup if the transaction
 431          * failed and we didn't already get a status write.
 432          */
 433         spin_lock_irqsave(&card->lock, flags);
 434
 435         if (orb->rcode == -1)
 436                 orb->rcode = rcode;
 437         if (orb->rcode != RCODE_COMPLETE) {
 438                 list_del(&orb->link);
 439                 spin_unlock_irqrestore(&card->lock, flags);
 440                 orb->callback(orb, NULL);
 441         } else {
 442                 spin_unlock_irqrestore(&card->lock, flags);
 443         }
 444
 445         kref_put(&orb->kref, free_orb);
 446 }
 447
 448 static void
 449 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 450               int node_id, int generation, u64 offset)
 451 {
 452         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 453         unsigned long flags;
 454
 455         orb->pointer.high = 0;
 456         orb->pointer.low = cpu_to_be32(orb->request_bus);
 457
 458         spin_lock_irqsave(&device->card->lock, flags);
 459         list_add_tail(&orb->link, &lu->orb_list);
 460         spin_unlock_irqrestore(&device->card->lock, flags);
 461
 462         /* Take a ref for the orb list and for the transaction callback. */
 463         kref_get(&orb->kref);
 464         kref_get(&orb->kref);
 465
 466         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 467                         node_id, generation, device->max_speed, offset,
 468                         &orb->pointer, sizeof(orb->pointer),
 469                         complete_transaction, orb);
 470 }
 471
 472 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 473 {
 474         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 475         struct sbp2_orb *orb, *next;
 476         struct list_head list;
 477         unsigned long flags;
 478         int retval = -ENOENT;
 479
 480         INIT_LIST_HEAD(&list);
 481         spin_lock_irqsave(&device->card->lock, flags);
 482         list_splice_init(&lu->orb_list, &list);
 483         spin_unlock_irqrestore(&device->card->lock, flags);
 484
 485         list_for_each_entry_safe(orb, next, &list, link) {
 486                 retval = 0;
 487                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 488                         continue;
 489
 490                 orb->rcode = RCODE_CANCELLED;
 491                 orb->callback(orb, NULL);
 492         }
 493
 494         return retval;
 495 }
 496
 497 static void
 498 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 499 {
 500         struct sbp2_management_orb *orb =
 501                 container_of(base_orb, struct sbp2_management_orb, base);
 502
 503         if (status)
 504                 memcpy(&orb->status, status, sizeof(*status));
 505         complete(&orb->done);
 506 }
 507
 508 static int
 509 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 510                          int generation, int function, int lun_or_login_id,
 511                          void *response)
 512 {
 513         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 514         struct sbp2_management_orb *orb;
 515         unsigned int timeout;
 516         int retval = -ENOMEM;
 517
 518         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 519                 return 0;
 520
 521         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 522         if (orb == NULL)
 523                 return -ENOMEM;
 524
 525         kref_init(&orb->base.kref);
 526         orb->response_bus =
 527                 dma_map_single(device->card->device, &orb->response,
 528                                sizeof(orb->response), DMA_FROM_DEVICE);
 529         if (dma_mapping_error(orb->response_bus))
 530                 goto fail_mapping_response;
 531
 532         orb->request.response.high = 0;
 533         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 534
 535         orb->request.misc = cpu_to_be32(
 536                 MANAGEMENT_ORB_NOTIFY |
 537                 MANAGEMENT_ORB_FUNCTION(function) |
 538                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 539         orb->request.length = cpu_to_be32(
 540                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 541
 542         orb->request.status_fifo.high =
 543                 cpu_to_be32(lu->address_handler.offset >> 32);
 544         orb->request.status_fifo.low  =
 545                 cpu_to_be32(lu->address_handler.offset);
 546
 547         if (function == SBP2_LOGIN_REQUEST) {
 548                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 549                 orb->request.misc |= cpu_to_be32(
 550                         MANAGEMENT_ORB_RECONNECT(2) |
 551                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 552                 timeout = lu->tgt->mgt_orb_timeout;
 553         } else {
 554                 timeout = SBP2_ORB_TIMEOUT;
 555         }
 556
 557         init_completion(&orb->done);
 558         orb->base.callback = complete_management_orb;
 559
 560         orb->base.request_bus =
 561                 dma_map_single(device->card->device, &orb->request,
 562                                sizeof(orb->request), DMA_TO_DEVICE);
 563         if (dma_mapping_error(orb->base.request_bus))
 564                 goto fail_mapping_request;
 565
 566         sbp2_send_orb(&orb->base, lu, node_id, generation,
 567                       lu->tgt->management_agent_address);
 568
 569         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 570
 571         retval = -EIO;
 572         if (sbp2_cancel_orbs(lu) == 0) {
 573                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 574                          lu->tgt->bus_id, orb->base.rcode);
 575                 goto out;
 576         }
 577
 578         if (orb->base.rcode != RCODE_COMPLETE) {
 579                 fw_error("%s: management write failed, rcode 0x%02x\n",
 580                          lu->tgt->bus_id, orb->base.rcode);
 581                 goto out;
 582         }
 583
 584         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 585             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 586                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 587                          STATUS_GET_RESPONSE(orb->status),
 588                          STATUS_GET_SBP_STATUS(orb->status));
 589                 goto out;
 590         }
 591
 592         retval = 0;
 593  out:
 594         dma_unmap_single(device->card->device, orb->base.request_bus,
 595                          sizeof(orb->request), DMA_TO_DEVICE);
 596  fail_mapping_request:
 597         dma_unmap_single(device->card->device, orb->response_bus,
 598                          sizeof(orb->response), DMA_FROM_DEVICE);
 599  fail_mapping_response:
 600         if (response)
 601                 memcpy(response, orb->response, sizeof(orb->response));
 602         kref_put(&orb->base.kref, free_orb);
 603
 604         return retval;
 605 }
 606
 607 static void
 608 complete_agent_reset_write(struct fw_card *card, int rcode,
 609                            void *payload, size_t length, void *done)
 610 {
 611         complete(done);
 612 }
 613
 614 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 615 {
 616         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 617         DECLARE_COMPLETION_ONSTACK(done);
 618         struct fw_transaction t;
 619         static u32 z;
 620
 621         fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
 622                         lu->tgt->node_id, lu->generation, device->max_speed,
 623                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 624                         &z, sizeof(z), complete_agent_reset_write, &done);
 625         wait_for_completion(&done);
 626 }
 627
 628 static void
 629 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 630                                    void *payload, size_t length, void *data)
 631 {
 632         kfree(data);
 633 }
 634
 635 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 636 {
 637         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 638         struct fw_transaction *t;
 639         static u32 z;
 640
 641         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 642         if (t == NULL)
 643                 return;
 644
 645         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 646                         lu->tgt->node_id, lu->generation, device->max_speed,
 647                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 648                         &z, sizeof(z), complete_agent_reset_write_no_wait, t);
 649 }
 650
 651 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
 652 {
 653         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
 654         unsigned long flags;
 655
 656         /* serialize with comparisons of lu->generation and card->generation */
 657         spin_lock_irqsave(&card->lock, flags);
 658         lu->generation = generation;
 659         spin_unlock_irqrestore(&card->lock, flags);
 660 }
 661
 662 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 663 {
 664         /*
 665          * We may access dont_block without taking card->lock here:
 666          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 667          * are currently serialized against each other.
 668          * And a wrong result in sbp2_conditionally_block()'s access of
 669          * dont_block is rather harmless, it simply misses its first chance.
 670          */
 671         --lu->tgt->dont_block;
 672 }
 673
 674 /*
 675  * Blocks lu->tgt if all of the following conditions are met:
 676  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 677  *     logical units have been finished (indicated by dont_block == 0).
 678  *   - lu->generation is stale.
 679  *
 680  * Note, scsi_block_requests() must be called while holding card->lock,
 681  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 682  * unblock the target.
 683  */
 684 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 685 {
 686         struct sbp2_target *tgt = lu->tgt;
 687         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 688         struct Scsi_Host *shost =
 689                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 690         unsigned long flags;
 691
 692         spin_lock_irqsave(&card->lock, flags);
 693         if (!tgt->dont_block && !lu->blocked &&
 694             lu->generation != card->generation) {
 695                 lu->blocked = true;
 696                 if (++tgt->blocked == 1)
 697                         scsi_block_requests(shost);
 698         }
 699         spin_unlock_irqrestore(&card->lock, flags);
 700 }
 701
 702 /*
 703  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 704  * Note, it is harmless to run scsi_unblock_requests() outside the
 705  * card->lock protected section.  On the other hand, running it inside
 706  * the section might clash with shost->host_lock.
 707  */
 708 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 709 {
 710         struct sbp2_target *tgt = lu->tgt;
 711         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 712         struct Scsi_Host *shost =
 713                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 714         unsigned long flags;
 715         bool unblock = false;
 716
 717         spin_lock_irqsave(&card->lock, flags);
 718         if (lu->blocked && lu->generation == card->generation) {
 719                 lu->blocked = false;
 720                 unblock = --tgt->blocked == 0;
 721         }
 722         spin_unlock_irqrestore(&card->lock, flags);
 723
 724         if (unblock)
 725                 scsi_unblock_requests(shost);
 726 }
 727
 728 /*
 729  * Prevents future blocking of tgt and unblocks it.
 730  * Note, it is harmless to run scsi_unblock_requests() outside the
 731  * card->lock protected section.  On the other hand, running it inside
 732  * the section might clash with shost->host_lock.
 733  */
 734 static void sbp2_unblock(struct sbp2_target *tgt)
 735 {
 736         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 737         struct Scsi_Host *shost =
 738                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 739         unsigned long flags;
 740
 741         spin_lock_irqsave(&card->lock, flags);
 742         ++tgt->dont_block;
 743         spin_unlock_irqrestore(&card->lock, flags);
 744
 745         scsi_unblock_requests(shost);
 746 }
 747
 748 static int sbp2_lun2int(u16 lun)
 749 {
 750         struct scsi_lun eight_bytes_lun;
 751
 752         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 753         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 754         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 755
 756         return scsilun_to_int(&eight_bytes_lun);
 757 }
 758
 759 static void sbp2_release_target(struct kref *kref)
 760 {
 761         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 762         struct sbp2_logical_unit *lu, *next;
 763         struct Scsi_Host *shost =
 764                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 765         struct scsi_device *sdev;
 766         struct fw_device *device = fw_device(tgt->unit->device.parent);
 767
 768         /* prevent deadlocks */
 769         sbp2_unblock(tgt);
 770
 771         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 772                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 773                 if (sdev) {
 774                         scsi_remove_device(sdev);
 775                         scsi_device_put(sdev);
 776                 }
 777                 sbp2_send_management_orb(lu, tgt->node_id, lu->generation,
 778                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 779
 780                 fw_core_remove_address_handler(&lu->address_handler);
 781                 list_del(&lu->link);
 782                 kfree(lu);
 783         }
 784         scsi_remove_host(shost);
 785         fw_notify("released %s\n", tgt->bus_id);
 786
 787         fw_unit_put(tgt->unit);
 788         scsi_host_put(shost);
 789         fw_device_put(device);
 790 }
 791
 792 static struct workqueue_struct *sbp2_wq;
 793
 794 /*
 795  * Always get the target's kref when scheduling work on one its units.
 796  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 797  */
 798 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 799 {
 800         if (queue_delayed_work(sbp2_wq, &lu->work, delay))
 801                 kref_get(&lu->tgt->kref);
 802 }
 803
 804 static void sbp2_target_put(struct sbp2_target *tgt)
 805 {
 806         kref_put(&tgt->kref, sbp2_release_target);
 807 }
 808
 809 static void
 810 complete_set_busy_timeout(struct fw_card *card, int rcode,
 811                           void *payload, size_t length, void *done)
 812 {
 813         complete(done);
 814 }
 815
 816 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 817 {
 818         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 819         DECLARE_COMPLETION_ONSTACK(done);
 820         struct fw_transaction t;
 821         static __be32 busy_timeout;
 822
 823         /* FIXME: we should try to set dual-phase cycle_limit too */
 824         busy_timeout = cpu_to_be32(SBP2_RETRY_LIMIT);
 825
 826         fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
 827                         lu->tgt->node_id, lu->generation, device->max_speed,
 828                         CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &busy_timeout,
 829                         sizeof(busy_timeout), complete_set_busy_timeout, &done);
 830         wait_for_completion(&done);
 831 }
 832
 833 static void sbp2_reconnect(struct work_struct *work);
 834
 835 static void sbp2_login(struct work_struct *work)
 836 {
 837         struct sbp2_logical_unit *lu =
 838                 container_of(work, struct sbp2_logical_unit, work.work);
 839         struct sbp2_target *tgt = lu->tgt;
 840         struct fw_device *device = fw_device(tgt->unit->device.parent);
 841         struct Scsi_Host *shost;
 842         struct scsi_device *sdev;
 843         struct sbp2_login_response response;
 844         int generation, node_id, local_node_id;
 845
 846         if (fw_device_is_shutdown(device))
 847                 goto out;
 848
 849         generation    = device->generation;
 850         smp_rmb();    /* node_id must not be older than generation */
 851         node_id       = device->node_id;
 852         local_node_id = device->card->node_id;
 853
 854         /* If this is a re-login attempt, log out, or we might be rejected. */
 855         if (lu->has_sdev)
 856                 sbp2_send_management_orb(lu, device->node_id, generation,
 857                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 858
 859         if (sbp2_send_management_orb(lu, node_id, generation,
 860                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 861                 if (lu->retries++ < 5) {
 862                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 863                 } else {
 864                         fw_error("%s: failed to login to LUN %04x\n",
 865                                  tgt->bus_id, lu->lun);
 866                         /* Let any waiting I/O fail from now on. */
 867                         sbp2_unblock(lu->tgt);
 868                 }
 869                 goto out;
 870         }
 871
 872         tgt->node_id      = node_id;
 873         tgt->address_high = local_node_id << 16;
 874         sbp2_set_generation(lu, generation);
 875
 876         lu->command_block_agent_address =
 877                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 878                       << 32) | be32_to_cpu(response.command_block_agent.low);
 879         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 880
 881         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 882                   tgt->bus_id, lu->lun, lu->retries);
 883
 884         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 885         sbp2_set_busy_timeout(lu);
 886
 887         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 888         sbp2_agent_reset(lu);
 889
 890         /* This was a re-login. */
 891         if (lu->has_sdev) {
 892                 sbp2_cancel_orbs(lu);
 893                 sbp2_conditionally_unblock(lu);
 894                 goto out;
 895         }
 896
 897         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 898                 ssleep(SBP2_INQUIRY_DELAY);
 899
 900         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 901         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 902         /*
 903          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 904          * Therefore __scsi_add_device() will get into trouble if a bus reset
 905          * happens in parallel.  It will either fail or leave us with an
 906          * unusable sdev.  As a workaround we check for this and retry the
 907          * whole login and SCSI probing.
 908          */
 909
 910         /* Reported error during __scsi_add_device() */
 911         if (IS_ERR(sdev))
 912                 goto out_logout_login;
 913
 914         /* Unreported error during __scsi_add_device() */
 915         smp_rmb(); /* get current card generation */
 916         if (generation != device->card->generation) {
 917                 scsi_remove_device(sdev);
 918                 scsi_device_put(sdev);
 919                 goto out_logout_login;
 920         }
 921
 922         /* No error during __scsi_add_device() */
 923         lu->has_sdev = true;
 924         scsi_device_put(sdev);
 925         sbp2_allow_block(lu);
 926         goto out;
 927
 928  out_logout_login:
 929         smp_rmb(); /* generation may have changed */
 930         generation = device->generation;
 931         smp_rmb(); /* node_id must not be older than generation */
 932
 933         sbp2_send_management_orb(lu, device->node_id, generation,
 934                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 935         /*
 936          * If a bus reset happened, sbp2_update will have requeued
 937          * lu->work already.  Reset the work from reconnect to login.
 938          */
 939         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 940  out:
 941         sbp2_target_put(tgt);
 942 }
 943
 944 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 945 {
 946         struct sbp2_logical_unit *lu;
 947
 948         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 949         if (!lu)
 950                 return -ENOMEM;
 951
 952         lu->address_handler.length           = 0x100;
 953         lu->address_handler.address_callback = sbp2_status_write;
 954         lu->address_handler.callback_data    = lu;
 955
 956         if (fw_core_add_address_handler(&lu->address_handler,
 957                                         &fw_high_memory_region) < 0) {
 958                 kfree(lu);
 959                 return -ENOMEM;
 960         }
 961
 962         lu->tgt      = tgt;
 963         lu->lun      = lun_entry & 0xffff;
 964         lu->retries  = 0;
 965         lu->has_sdev = false;
 966         lu->blocked  = false;
 967         ++tgt->dont_block;
 968         INIT_LIST_HEAD(&lu->orb_list);
 969         INIT_DELAYED_WORK(&lu->work, sbp2_login);
 970
 971         list_add_tail(&lu->link, &tgt->lu_list);
 972         return 0;
 973 }
 974
 975 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
 976 {
 977         struct fw_csr_iterator ci;
 978         int key, value;
 979
 980         fw_csr_iterator_init(&ci, directory);
 981         while (fw_csr_iterator_next(&ci, &key, &value))
 982                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
 983                     sbp2_add_logical_unit(tgt, value) < 0)
 984                         return -ENOMEM;
 985         return 0;
 986 }
 987
 988 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
 989                               u32 *model, u32 *firmware_revision)
 990 {
 991         struct fw_csr_iterator ci;
 992         int key, value;
 993         unsigned int timeout;
 994
 995         fw_csr_iterator_init(&ci, directory);
 996         while (fw_csr_iterator_next(&ci, &key, &value)) {
 997                 switch (key) {
 998
 999                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1000                         tgt->management_agent_address =
1001                                         CSR_REGISTER_BASE + 4 * value;
1002                         break;
1003
1004                 case CSR_DIRECTORY_ID:
1005                         tgt->directory_id = value;
1006                         break;
1007
1008                 case CSR_MODEL:
1009                         *model = value;
1010                         break;
1011
1012                 case SBP2_CSR_FIRMWARE_REVISION:
1013                         *firmware_revision = value;
1014                         break;
1015
1016                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1017                         /* the timeout value is stored in 500ms units */
1018                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1019                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1020                         tgt->mgt_orb_timeout =
1021                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1022
1023                         if (timeout > tgt->mgt_orb_timeout)
1024                                 fw_notify("%s: config rom contains %ds "
1025                                           "management ORB timeout, limiting "
1026                                           "to %ds\n", tgt->bus_id,
1027                                           timeout / 1000,
1028                                           tgt->mgt_orb_timeout / 1000);
1029                         break;
1030
1031                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1032                         if (sbp2_add_logical_unit(tgt, value) < 0)
1033                                 return -ENOMEM;
1034                         break;
1035
1036                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1037                         if (sbp2_scan_logical_unit_dir(tgt, ci.p + value) < 0)
1038                                 return -ENOMEM;
1039                         break;
1040                 }
1041         }
1042         return 0;
1043 }
1044
1045 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1046                                   u32 firmware_revision)
1047 {
1048         int i;
1049         unsigned int w = sbp2_param_workarounds;
1050
1051         if (w)
1052                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1053                           "if you need the workarounds parameter for %s\n",
1054                           tgt->bus_id);
1055
1056         if (w & SBP2_WORKAROUND_OVERRIDE)
1057                 goto out;
1058
1059         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1060
1061                 if (sbp2_workarounds_table[i].firmware_revision !=
1062                     (firmware_revision & 0xffffff00))
1063                         continue;
1064
1065                 if (sbp2_workarounds_table[i].model != model &&
1066                     sbp2_workarounds_table[i].model != ~0)
1067                         continue;
1068
1069                 w |= sbp2_workarounds_table[i].workarounds;
1070                 break;
1071         }
1072  out:
1073         if (w)
1074                 fw_notify("Workarounds for %s: 0x%x "
1075                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1076                           tgt->bus_id, w, firmware_revision, model);
1077         tgt->workarounds = w;
1078 }
1079
1080 static struct scsi_host_template scsi_driver_template;
1081
1082 static int sbp2_probe(struct device *dev)
1083 {
1084         struct fw_unit *unit = fw_unit(dev);
1085         struct fw_device *device = fw_device(unit->device.parent);
1086         struct sbp2_target *tgt;
1087         struct sbp2_logical_unit *lu;
1088         struct Scsi_Host *shost;
1089         u32 model, firmware_revision;
1090
1091         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1092         if (shost == NULL)
1093                 return -ENOMEM;
1094
1095         tgt = (struct sbp2_target *)shost->hostdata;
1096         unit->device.driver_data = tgt;
1097         tgt->unit = unit;
1098         kref_init(&tgt->kref);
1099         INIT_LIST_HEAD(&tgt->lu_list);
1100         tgt->bus_id = unit->device.bus_id;
1101
1102         if (fw_device_enable_phys_dma(device) < 0)
1103                 goto fail_shost_put;
1104
1105         if (scsi_add_host(shost, &unit->device) < 0)
1106                 goto fail_shost_put;
1107
1108         fw_device_get(device);
1109         fw_unit_get(unit);
1110
1111         /* Initialize to values that won't match anything in our table. */
1112         firmware_revision = 0xff000000;
1113         model = 0xff000000;
1114
1115         /* implicit directory ID */
1116         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1117                              + CSR_CONFIG_ROM) & 0xffffff;
1118
1119         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1120                                &firmware_revision) < 0)
1121                 goto fail_tgt_put;
1122
1123         sbp2_init_workarounds(tgt, model, firmware_revision);
1124
1125         /* Do the login in a workqueue so we can easily reschedule retries. */
1126         list_for_each_entry(lu, &tgt->lu_list, link)
1127                 sbp2_queue_work(lu, 0);
1128         return 0;
1129
1130  fail_tgt_put:
1131         sbp2_target_put(tgt);
1132         return -ENOMEM;
1133
1134  fail_shost_put:
1135         scsi_host_put(shost);
1136         return -ENOMEM;
1137 }
1138
1139 static int sbp2_remove(struct device *dev)
1140 {
1141         struct fw_unit *unit = fw_unit(dev);
1142         struct sbp2_target *tgt = unit->device.driver_data;
1143
1144         sbp2_target_put(tgt);
1145         return 0;
1146 }
1147
1148 static void sbp2_reconnect(struct work_struct *work)
1149 {
1150         struct sbp2_logical_unit *lu =
1151                 container_of(work, struct sbp2_logical_unit, work.work);
1152         struct sbp2_target *tgt = lu->tgt;
1153         struct fw_device *device = fw_device(tgt->unit->device.parent);
1154         int generation, node_id, local_node_id;
1155
1156         if (fw_device_is_shutdown(device))
1157                 goto out;
1158
1159         generation    = device->generation;
1160         smp_rmb();    /* node_id must not be older than generation */
1161         node_id       = device->node_id;
1162         local_node_id = device->card->node_id;
1163
1164         if (sbp2_send_management_orb(lu, node_id, generation,
1165                                      SBP2_RECONNECT_REQUEST,
1166                                      lu->login_id, NULL) < 0) {
1167                 /*
1168                  * If reconnect was impossible even though we are in the
1169                  * current generation, fall back and try to log in again.
1170                  *
1171                  * We could check for "Function rejected" status, but
1172                  * looking at the bus generation as simpler and more general.
1173                  */
1174                 smp_rmb(); /* get current card generation */
1175                 if (generation == device->card->generation ||
1176                     lu->retries++ >= 5) {
1177                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1178                         lu->retries = 0;
1179                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1180                 }
1181                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1182                 goto out;
1183         }
1184
1185         tgt->node_id      = node_id;
1186         tgt->address_high = local_node_id << 16;
1187         sbp2_set_generation(lu, generation);
1188
1189         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1190                   tgt->bus_id, lu->lun, lu->retries);
1191
1192         sbp2_agent_reset(lu);
1193         sbp2_cancel_orbs(lu);
1194         sbp2_conditionally_unblock(lu);
1195  out:
1196         sbp2_target_put(tgt);
1197 }
1198
1199 static void sbp2_update(struct fw_unit *unit)
1200 {
1201         struct sbp2_target *tgt = unit->device.driver_data;
1202         struct sbp2_logical_unit *lu;
1203
1204         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1205
1206         /*
1207          * Fw-core serializes sbp2_update() against sbp2_remove().
1208          * Iteration over tgt->lu_list is therefore safe here.
1209          */
1210         list_for_each_entry(lu, &tgt->lu_list, link) {
1211                 sbp2_conditionally_block(lu);
1212                 lu->retries = 0;
1213                 sbp2_queue_work(lu, 0);
1214         }
1215 }
1216
1217 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1218 #define SBP2_SW_VERSION_ENTRY   0x00010483
1219
1220 static const struct fw_device_id sbp2_id_table[] = {
1221         {
1222                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1223                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1224                 .version      = SBP2_SW_VERSION_ENTRY,
1225         },
1226         { }
1227 };
1228
1229 static struct fw_driver sbp2_driver = {
1230         .driver   = {
1231                 .owner  = THIS_MODULE,
1232                 .name   = sbp2_driver_name,
1233                 .bus    = &fw_bus_type,
1234                 .probe  = sbp2_probe,
1235                 .remove = sbp2_remove,
1236         },
1237         .update   = sbp2_update,
1238         .id_table = sbp2_id_table,
1239 };
1240
1241 static unsigned int
1242 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1243 {
1244         int sam_status;
1245
1246         sense_data[0] = 0x70;
1247         sense_data[1] = 0x0;
1248         sense_data[2] = sbp2_status[1];
1249         sense_data[3] = sbp2_status[4];
1250         sense_data[4] = sbp2_status[5];
1251         sense_data[5] = sbp2_status[6];
1252         sense_data[6] = sbp2_status[7];
1253         sense_data[7] = 10;
1254         sense_data[8] = sbp2_status[8];
1255         sense_data[9] = sbp2_status[9];
1256         sense_data[10] = sbp2_status[10];
1257         sense_data[11] = sbp2_status[11];
1258         sense_data[12] = sbp2_status[2];
1259         sense_data[13] = sbp2_status[3];
1260         sense_data[14] = sbp2_status[12];
1261         sense_data[15] = sbp2_status[13];
1262
1263         sam_status = sbp2_status[0] & 0x3f;
1264
1265         switch (sam_status) {
1266         case SAM_STAT_GOOD:
1267         case SAM_STAT_CHECK_CONDITION:
1268         case SAM_STAT_CONDITION_MET:
1269         case SAM_STAT_BUSY:
1270         case SAM_STAT_RESERVATION_CONFLICT:
1271         case SAM_STAT_COMMAND_TERMINATED:
1272                 return DID_OK << 16 | sam_status;
1273
1274         default:
1275                 return DID_ERROR << 16;
1276         }
1277 }
1278
1279 static void
1280 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1281 {
1282         struct sbp2_command_orb *orb =
1283                 container_of(base_orb, struct sbp2_command_orb, base);
1284         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1285         int result;
1286
1287         if (status != NULL) {
1288                 if (STATUS_GET_DEAD(*status))
1289                         sbp2_agent_reset_no_wait(orb->lu);
1290
1291                 switch (STATUS_GET_RESPONSE(*status)) {
1292                 case SBP2_STATUS_REQUEST_COMPLETE:
1293                         result = DID_OK << 16;
1294                         break;
1295                 case SBP2_STATUS_TRANSPORT_FAILURE:
1296                         result = DID_BUS_BUSY << 16;
1297                         break;
1298                 case SBP2_STATUS_ILLEGAL_REQUEST:
1299                 case SBP2_STATUS_VENDOR_DEPENDENT:
1300                 default:
1301                         result = DID_ERROR << 16;
1302                         break;
1303                 }
1304
1305                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1306                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1307                                                            orb->cmd->sense_buffer);
1308         } else {
1309                 /*
1310                  * If the orb completes with status == NULL, something
1311                  * went wrong, typically a bus reset happened mid-orb
1312                  * or when sending the write (less likely).
1313                  */
1314                 result = DID_BUS_BUSY << 16;
1315                 sbp2_conditionally_block(orb->lu);
1316         }
1317
1318         dma_unmap_single(device->card->device, orb->base.request_bus,
1319                          sizeof(orb->request), DMA_TO_DEVICE);
1320
1321         if (scsi_sg_count(orb->cmd) > 0)
1322                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1323                              scsi_sg_count(orb->cmd),
1324                              orb->cmd->sc_data_direction);
1325
1326         if (orb->page_table_bus != 0)
1327                 dma_unmap_single(device->card->device, orb->page_table_bus,
1328                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1329
1330         orb->cmd->result = result;
1331         orb->done(orb->cmd);
1332 }
1333
1334 static int
1335 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1336                      struct sbp2_logical_unit *lu)
1337 {
1338         struct scatterlist *sg;
1339         int sg_len, l, i, j, count;
1340         dma_addr_t sg_addr;
1341
1342         sg = scsi_sglist(orb->cmd);
1343         count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1344                            orb->cmd->sc_data_direction);
1345         if (count == 0)
1346                 goto fail;
1347
1348         /*
1349          * Handle the special case where there is only one element in
1350          * the scatter list by converting it to an immediate block
1351          * request. This is also a workaround for broken devices such
1352          * as the second generation iPod which doesn't support page
1353          * tables.
1354          */
1355         if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) {
1356                 orb->request.data_descriptor.high =
1357                         cpu_to_be32(lu->tgt->address_high);
1358                 orb->request.data_descriptor.low  =
1359                         cpu_to_be32(sg_dma_address(sg));
1360                 orb->request.misc |=
1361                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1362                 return 0;
1363         }
1364
1365         /*
1366          * Convert the scatterlist to an sbp2 page table.  If any
1367          * scatterlist entries are too big for sbp2, we split them as we
1368          * go.  Even if we ask the block I/O layer to not give us sg
1369          * elements larger than 65535 bytes, some IOMMUs may merge sg elements
1370          * during DMA mapping, and Linux currently doesn't prevent this.
1371          */
1372         for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) {
1373                 sg_len = sg_dma_len(sg);
1374                 sg_addr = sg_dma_address(sg);
1375                 while (sg_len) {
1376                         /* FIXME: This won't get us out of the pinch. */
1377                         if (unlikely(j >= ARRAY_SIZE(orb->page_table))) {
1378                                 fw_error("page table overflow\n");
1379                                 goto fail_page_table;
1380                         }
1381                         l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH);
1382                         orb->page_table[j].low = cpu_to_be32(sg_addr);
1383                         orb->page_table[j].high = cpu_to_be32(l << 16);
1384                         sg_addr += l;
1385                         sg_len -= l;
1386                         j++;
1387                 }
1388         }
1389
1390         orb->page_table_bus =
1391                 dma_map_single(device->card->device, orb->page_table,
1392                                sizeof(orb->page_table), DMA_TO_DEVICE);
1393         if (dma_mapping_error(orb->page_table_bus))
1394                 goto fail_page_table;
1395
1396         /*
1397          * The data_descriptor pointer is the one case where we need
1398          * to fill in the node ID part of the address.  All other
1399          * pointers assume that the data referenced reside on the
1400          * initiator (i.e. us), but data_descriptor can refer to data
1401          * on other nodes so we need to put our ID in descriptor.high.
1402          */
1403         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1404         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1405         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1406                                          COMMAND_ORB_DATA_SIZE(j));
1407
1408         return 0;
1409
1410  fail_page_table:
1411         dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1412                      orb->cmd->sc_data_direction);
1413  fail:
1414         return -ENOMEM;
1415 }
1416
1417 /* SCSI stack integration */
1418
1419 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1420 {
1421         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1422         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1423         struct sbp2_command_orb *orb;
1424         unsigned int max_payload;
1425         int retval = SCSI_MLQUEUE_HOST_BUSY;
1426
1427         /*
1428          * Bidirectional commands are not yet implemented, and unknown
1429          * transfer direction not handled.
1430          */
1431         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1432                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1433                 cmd->result = DID_ERROR << 16;
1434                 done(cmd);
1435                 return 0;
1436         }
1437
1438         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1439         if (orb == NULL) {
1440                 fw_notify("failed to alloc orb\n");
1441                 return SCSI_MLQUEUE_HOST_BUSY;
1442         }
1443
1444         /* Initialize rcode to something not RCODE_COMPLETE. */
1445         orb->base.rcode = -1;
1446         kref_init(&orb->base.kref);
1447
1448         orb->lu   = lu;
1449         orb->done = done;
1450         orb->cmd  = cmd;
1451
1452         orb->request.next.high   = cpu_to_be32(SBP2_ORB_NULL);
1453         /*
1454          * At speed 100 we can do 512 bytes per packet, at speed 200,
1455          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1456          * specifies the max payload size as 2 ^ (max_payload + 2), so
1457          * if we set this to max_speed + 7, we get the right value.
1458          */
1459         max_payload = min(device->max_speed + 7,
1460                           device->card->max_receive - 1);
1461         orb->request.misc = cpu_to_be32(
1462                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1463                 COMMAND_ORB_SPEED(device->max_speed) |
1464                 COMMAND_ORB_NOTIFY);
1465
1466         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1467                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1468
1469         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1470                 goto out;
1471
1472         memcpy(orb->request.command_block, cmd->cmnd, COMMAND_SIZE(*cmd->cmnd));
1473
1474         orb->base.callback = complete_command_orb;
1475         orb->base.request_bus =
1476                 dma_map_single(device->card->device, &orb->request,
1477                                sizeof(orb->request), DMA_TO_DEVICE);
1478         if (dma_mapping_error(orb->base.request_bus))
1479                 goto out;
1480
1481         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, lu->generation,
1482                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1483         retval = 0;
1484  out:
1485         kref_put(&orb->base.kref, free_orb);
1486         return retval;
1487 }
1488
1489 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1490 {
1491         struct sbp2_logical_unit *lu = sdev->hostdata;
1492
1493         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1494         if (!lu)
1495                 return -ENOSYS;
1496
1497         sdev->allow_restart = 1;
1498
1499         /* SBP-2 requires quadlet alignment of the data buffers. */
1500         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1501
1502         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1503                 sdev->inquiry_len = 36;
1504
1505         return 0;
1506 }
1507
1508 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1509 {
1510         struct sbp2_logical_unit *lu = sdev->hostdata;
1511
1512         sdev->use_10_for_rw = 1;
1513
1514         if (sdev->type == TYPE_ROM)
1515                 sdev->use_10_for_ms = 1;
1516
1517         if (sdev->type == TYPE_DISK &&
1518             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1519                 sdev->skip_ms_page_8 = 1;
1520
1521         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1522                 sdev->fix_capacity = 1;
1523
1524         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1525                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1526
1527         return 0;
1528 }
1529
1530 /*
1531  * Called by scsi stack when something has really gone wrong.  Usually
1532  * called when a command has timed-out for some reason.
1533  */
1534 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1535 {
1536         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1537
1538         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1539         sbp2_agent_reset(lu);
1540         sbp2_cancel_orbs(lu);
1541
1542         return SUCCESS;
1543 }
1544
1545 /*
1546  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1547  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1548  *
1549  * This is the concatenation of target port identifier and logical unit
1550  * identifier as per SAM-2...SAM-4 annex A.
1551  */
1552 static ssize_t
1553 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1554                             char *buf)
1555 {
1556         struct scsi_device *sdev = to_scsi_device(dev);
1557         struct sbp2_logical_unit *lu;
1558         struct fw_device *device;
1559
1560         if (!sdev)
1561                 return 0;
1562
1563         lu = sdev->hostdata;
1564         device = fw_device(lu->tgt->unit->device.parent);
1565
1566         return sprintf(buf, "%08x%08x:%06x:%04x\n",
1567                         device->config_rom[3], device->config_rom[4],
1568                         lu->tgt->directory_id, lu->lun);
1569 }
1570
1571 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1572
1573 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1574         &dev_attr_ieee1394_id,
1575         NULL
1576 };
1577
1578 static struct scsi_host_template scsi_driver_template = {
1579         .module                 = THIS_MODULE,
1580         .name                   = "SBP-2 IEEE-1394",
1581         .proc_name              = sbp2_driver_name,
1582         .queuecommand           = sbp2_scsi_queuecommand,
1583         .slave_alloc            = sbp2_scsi_slave_alloc,
1584         .slave_configure        = sbp2_scsi_slave_configure,
1585         .eh_abort_handler       = sbp2_scsi_abort,
1586         .this_id                = -1,
1587         .sg_tablesize           = SG_ALL,
1588         .use_clustering         = ENABLE_CLUSTERING,
1589         .cmd_per_lun            = 1,
1590         .can_queue              = 1,
1591         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1592 };
1593
1594 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1595 MODULE_DESCRIPTION("SCSI over IEEE1394");
1596 MODULE_LICENSE("GPL");
1597 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1598
1599 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1600 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1601 MODULE_ALIAS("sbp2");
1602 #endif
1603
1604 static int __init sbp2_init(void)
1605 {
1606         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1607         if (!sbp2_wq)
1608                 return -ENOMEM;
1609
1610         return driver_register(&sbp2_driver.driver);
1611 }
1612
1613 static void __exit sbp2_cleanup(void)
1614 {
1615         driver_unregister(&sbp2_driver.driver);
1616         destroy_workqueue(sbp2_wq);
1617 }
1618
1619 module_init(sbp2_init);
1620 module_exit(sbp2_cleanup);