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 scsi_device *sdev;
 126         struct fw_address_handler address_handler;
 127         struct list_head orb_list;
 128
 129         u64 command_block_agent_address;
 130         u16 lun;
 131         int login_id;
 132
 133         /*
 134          * The generation is updated once we've logged in or reconnected
 135          * to the logical unit.  Thus, I/O to the device will automatically
 136          * fail and get retried if it happens in a window where the device
 137          * is not ready, e.g. after a bus reset but before we reconnect.
 138          */
 139         int generation;
 140         int retries;
 141         struct delayed_work work;
 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
 177 #define SBP2_DIRECTION_TO_MEDIA         0x0
 178 #define SBP2_DIRECTION_FROM_MEDIA       0x1
 179
 180 /* Unit directory keys */
 181 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 182 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 183 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 184 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 185
 186 /* Management orb opcodes */
 187 #define SBP2_LOGIN_REQUEST              0x0
 188 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 189 #define SBP2_RECONNECT_REQUEST          0x3
 190 #define SBP2_SET_PASSWORD_REQUEST       0x4
 191 #define SBP2_LOGOUT_REQUEST             0x7
 192 #define SBP2_ABORT_TASK_REQUEST         0xb
 193 #define SBP2_ABORT_TASK_SET             0xc
 194 #define SBP2_LOGICAL_UNIT_RESET         0xe
 195 #define SBP2_TARGET_RESET_REQUEST       0xf
 196
 197 /* Offsets for command block agent registers */
 198 #define SBP2_AGENT_STATE                0x00
 199 #define SBP2_AGENT_RESET                0x04
 200 #define SBP2_ORB_POINTER                0x08
 201 #define SBP2_DOORBELL                   0x10
 202 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 203
 204 /* Status write response codes */
 205 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 206 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 207 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 208 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 209
 210 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 211 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 212 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 213 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 214 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 215 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 216 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 217 #define STATUS_GET_DATA(v)              ((v).data)
 218
 219 struct sbp2_status {
 220         u32 status;
 221         u32 orb_low;
 222         u8 data[24];
 223 };
 224
 225 struct sbp2_pointer {
 226         u32 high;
 227         u32 low;
 228 };
 229
 230 struct sbp2_orb {
 231         struct fw_transaction t;
 232         struct kref kref;
 233         dma_addr_t request_bus;
 234         int rcode;
 235         struct sbp2_pointer pointer;
 236         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 237         struct list_head link;
 238 };
 239
 240 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 241 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 242 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 243 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 244 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 245 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 246
 247 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 248 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 249
 250 struct sbp2_management_orb {
 251         struct sbp2_orb base;
 252         struct {
 253                 struct sbp2_pointer password;
 254                 struct sbp2_pointer response;
 255                 u32 misc;
 256                 u32 length;
 257                 struct sbp2_pointer status_fifo;
 258         } request;
 259         __be32 response[4];
 260         dma_addr_t response_bus;
 261         struct completion done;
 262         struct sbp2_status status;
 263 };
 264
 265 #define LOGIN_RESPONSE_GET_LOGIN_ID(v)  ((v).misc & 0xffff)
 266 #define LOGIN_RESPONSE_GET_LENGTH(v)    (((v).misc >> 16) & 0xffff)
 267
 268 struct sbp2_login_response {
 269         u32 misc;
 270         struct sbp2_pointer command_block_agent;
 271         u32 reconnect_hold;
 272 };
 273 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 274 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 275 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 276 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 277 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 278 #define COMMAND_ORB_DIRECTION(v)        ((v) << 27)
 279 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 280 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 281
 282 struct sbp2_command_orb {
 283         struct sbp2_orb base;
 284         struct {
 285                 struct sbp2_pointer next;
 286                 struct sbp2_pointer data_descriptor;
 287                 u32 misc;
 288                 u8 command_block[12];
 289         } request;
 290         struct scsi_cmnd *cmd;
 291         scsi_done_fn_t done;
 292         struct sbp2_logical_unit *lu;
 293
 294         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 295         dma_addr_t page_table_bus;
 296 };
 297
 298 /*
 299  * List of devices with known bugs.
 300  *
 301  * The firmware_revision field, masked with 0xffff00, is the best
 302  * indicator for the type of bridge chip of a device.  It yields a few
 303  * false positives but this did not break correctly behaving devices
 304  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
 305  * from the config rom can never match that.
 306  */
 307 static const struct {
 308         u32 firmware_revision;
 309         u32 model;
 310         unsigned int workarounds;
 311 } sbp2_workarounds_table[] = {
 312         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 313                 .firmware_revision      = 0x002800,
 314                 .model                  = 0x001010,
 315                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 316                                           SBP2_WORKAROUND_MODE_SENSE_8,
 317         },
 318         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 319                 .firmware_revision      = 0x002800,
 320                 .model                  = 0x000000,
 321                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY,
 322         },
 323         /* Initio bridges, actually only needed for some older ones */ {
 324                 .firmware_revision      = 0x000200,
 325                 .model                  = ~0,
 326                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 327         },
 328         /* Symbios bridge */ {
 329                 .firmware_revision      = 0xa0b800,
 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 = orb->request_bus;
 457         fw_memcpy_to_be32(&orb->pointer, &orb->pointer, sizeof(orb->pointer));
 458
 459         spin_lock_irqsave(&device->card->lock, flags);
 460         list_add_tail(&orb->link, &lu->orb_list);
 461         spin_unlock_irqrestore(&device->card->lock, flags);
 462
 463         /* Take a ref for the orb list and for the transaction callback. */
 464         kref_get(&orb->kref);
 465         kref_get(&orb->kref);
 466
 467         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 468                         node_id, generation, device->max_speed, offset,
 469                         &orb->pointer, sizeof(orb->pointer),
 470                         complete_transaction, orb);
 471 }
 472
 473 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 474 {
 475         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 476         struct sbp2_orb *orb, *next;
 477         struct list_head list;
 478         unsigned long flags;
 479         int retval = -ENOENT;
 480
 481         INIT_LIST_HEAD(&list);
 482         spin_lock_irqsave(&device->card->lock, flags);
 483         list_splice_init(&lu->orb_list, &list);
 484         spin_unlock_irqrestore(&device->card->lock, flags);
 485
 486         list_for_each_entry_safe(orb, next, &list, link) {
 487                 retval = 0;
 488                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 489                         continue;
 490
 491                 orb->rcode = RCODE_CANCELLED;
 492                 orb->callback(orb, NULL);
 493         }
 494
 495         return retval;
 496 }
 497
 498 static void
 499 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
 500 {
 501         struct sbp2_management_orb *orb =
 502                 container_of(base_orb, struct sbp2_management_orb, base);
 503
 504         if (status)
 505                 memcpy(&orb->status, status, sizeof(*status));
 506         complete(&orb->done);
 507 }
 508
 509 static int
 510 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 511                          int generation, int function, int lun_or_login_id,
 512                          void *response)
 513 {
 514         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 515         struct sbp2_management_orb *orb;
 516         unsigned int timeout;
 517         int retval = -ENOMEM;
 518
 519         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 520                 return 0;
 521
 522         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 523         if (orb == NULL)
 524                 return -ENOMEM;
 525
 526         kref_init(&orb->base.kref);
 527         orb->response_bus =
 528                 dma_map_single(device->card->device, &orb->response,
 529                                sizeof(orb->response), DMA_FROM_DEVICE);
 530         if (dma_mapping_error(orb->response_bus))
 531                 goto fail_mapping_response;
 532
 533         orb->request.response.high    = 0;
 534         orb->request.response.low     = orb->response_bus;
 535
 536         orb->request.misc =
 537                 MANAGEMENT_ORB_NOTIFY |
 538                 MANAGEMENT_ORB_FUNCTION(function) |
 539                 MANAGEMENT_ORB_LUN(lun_or_login_id);
 540         orb->request.length =
 541                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response));
 542
 543         orb->request.status_fifo.high = lu->address_handler.offset >> 32;
 544         orb->request.status_fifo.low  = lu->address_handler.offset;
 545
 546         if (function == SBP2_LOGIN_REQUEST) {
 547                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 548                 orb->request.misc |=
 549                         MANAGEMENT_ORB_RECONNECT(2) |
 550                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login);
 551                 timeout = lu->tgt->mgt_orb_timeout;
 552         } else {
 553                 timeout = SBP2_ORB_TIMEOUT;
 554         }
 555
 556         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
 557
 558         init_completion(&orb->done);
 559         orb->base.callback = complete_management_orb;
 560
 561         orb->base.request_bus =
 562                 dma_map_single(device->card->device, &orb->request,
 563                                sizeof(orb->request), DMA_TO_DEVICE);
 564         if (dma_mapping_error(orb->base.request_bus))
 565                 goto fail_mapping_request;
 566
 567         sbp2_send_orb(&orb->base, lu, node_id, generation,
 568                       lu->tgt->management_agent_address);
 569
 570         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 571
 572         retval = -EIO;
 573         if (sbp2_cancel_orbs(lu) == 0) {
 574                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 575                          lu->tgt->bus_id, orb->base.rcode);
 576                 goto out;
 577         }
 578
 579         if (orb->base.rcode != RCODE_COMPLETE) {
 580                 fw_error("%s: management write failed, rcode 0x%02x\n",
 581                          lu->tgt->bus_id, orb->base.rcode);
 582                 goto out;
 583         }
 584
 585         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 586             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 587                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 588                          STATUS_GET_RESPONSE(orb->status),
 589                          STATUS_GET_SBP_STATUS(orb->status));
 590                 goto out;
 591         }
 592
 593         retval = 0;
 594  out:
 595         dma_unmap_single(device->card->device, orb->base.request_bus,
 596                          sizeof(orb->request), DMA_TO_DEVICE);
 597  fail_mapping_request:
 598         dma_unmap_single(device->card->device, orb->response_bus,
 599                          sizeof(orb->response), DMA_FROM_DEVICE);
 600  fail_mapping_response:
 601         if (response)
 602                 fw_memcpy_from_be32(response,
 603                                     orb->response, sizeof(orb->response));
 604         kref_put(&orb->base.kref, free_orb);
 605
 606         return retval;
 607 }
 608
 609 static void
 610 complete_agent_reset_write(struct fw_card *card, int rcode,
 611                            void *payload, size_t length, void *done)
 612 {
 613         complete(done);
 614 }
 615
 616 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 617 {
 618         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 619         DECLARE_COMPLETION_ONSTACK(done);
 620         struct fw_transaction t;
 621         static u32 z;
 622
 623         fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
 624                         lu->tgt->node_id, lu->generation, device->max_speed,
 625                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 626                         &z, sizeof(z), complete_agent_reset_write, &done);
 627         wait_for_completion(&done);
 628 }
 629
 630 static void
 631 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
 632                                    void *payload, size_t length, void *data)
 633 {
 634         kfree(data);
 635 }
 636
 637 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 638 {
 639         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 640         struct fw_transaction *t;
 641         static u32 z;
 642
 643         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 644         if (t == NULL)
 645                 return;
 646
 647         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 648                         lu->tgt->node_id, lu->generation, device->max_speed,
 649                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 650                         &z, sizeof(z), complete_agent_reset_write_no_wait, t);
 651 }
 652
 653 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
 654 {
 655         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
 656         unsigned long flags;
 657
 658         /* serialize with comparisons of lu->generation and card->generation */
 659         spin_lock_irqsave(&card->lock, flags);
 660         lu->generation = generation;
 661         spin_unlock_irqrestore(&card->lock, flags);
 662 }
 663
 664 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 665 {
 666         /*
 667          * We may access dont_block without taking card->lock here:
 668          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 669          * are currently serialized against each other.
 670          * And a wrong result in sbp2_conditionally_block()'s access of
 671          * dont_block is rather harmless, it simply misses its first chance.
 672          */
 673         --lu->tgt->dont_block;
 674 }
 675
 676 /*
 677  * Blocks lu->tgt if all of the following conditions are met:
 678  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 679  *     logical units have been finished (indicated by dont_block == 0).
 680  *   - lu->generation is stale.
 681  *
 682  * Note, scsi_block_requests() must be called while holding card->lock,
 683  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 684  * unblock the target.
 685  */
 686 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 687 {
 688         struct sbp2_target *tgt = lu->tgt;
 689         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 690         struct Scsi_Host *shost =
 691                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 692         unsigned long flags;
 693
 694         spin_lock_irqsave(&card->lock, flags);
 695         if (!tgt->dont_block && !lu->blocked &&
 696             lu->generation != card->generation) {
 697                 lu->blocked = true;
 698                 if (++tgt->blocked == 1) {
 699                         scsi_block_requests(shost);
 700                         fw_notify("blocked %s\n", lu->tgt->bus_id);
 701                 }
 702         }
 703         spin_unlock_irqrestore(&card->lock, flags);
 704 }
 705
 706 /*
 707  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 708  * Note, it is harmless to run scsi_unblock_requests() outside the
 709  * card->lock protected section.  On the other hand, running it inside
 710  * the section might clash with shost->host_lock.
 711  */
 712 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 713 {
 714         struct sbp2_target *tgt = lu->tgt;
 715         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 716         struct Scsi_Host *shost =
 717                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 718         unsigned long flags;
 719         bool unblock = false;
 720
 721         spin_lock_irqsave(&card->lock, flags);
 722         if (lu->blocked && lu->generation == card->generation) {
 723                 lu->blocked = false;
 724                 unblock = --tgt->blocked == 0;
 725         }
 726         spin_unlock_irqrestore(&card->lock, flags);
 727
 728         if (unblock) {
 729                 scsi_unblock_requests(shost);
 730                 fw_notify("unblocked %s\n", lu->tgt->bus_id);
 731         }
 732 }
 733
 734 /*
 735  * Prevents future blocking of tgt and unblocks it.
 736  * Note, it is harmless to run scsi_unblock_requests() outside the
 737  * card->lock protected section.  On the other hand, running it inside
 738  * the section might clash with shost->host_lock.
 739  */
 740 static void sbp2_unblock(struct sbp2_target *tgt)
 741 {
 742         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
 743         struct Scsi_Host *shost =
 744                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 745         unsigned long flags;
 746
 747         spin_lock_irqsave(&card->lock, flags);
 748         ++tgt->dont_block;
 749         spin_unlock_irqrestore(&card->lock, flags);
 750
 751         scsi_unblock_requests(shost);
 752 }
 753
 754 static void sbp2_release_target(struct kref *kref)
 755 {
 756         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 757         struct sbp2_logical_unit *lu, *next;
 758         struct Scsi_Host *shost =
 759                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 760
 761         /* prevent deadlocks */
 762         sbp2_unblock(tgt);
 763
 764         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 765                 if (lu->sdev) {
 766                         scsi_remove_device(lu->sdev);
 767                         scsi_device_put(lu->sdev);
 768                 }
 769                 sbp2_send_management_orb(lu, tgt->node_id, lu->generation,
 770                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 771
 772                 fw_core_remove_address_handler(&lu->address_handler);
 773                 list_del(&lu->link);
 774                 kfree(lu);
 775         }
 776         scsi_remove_host(shost);
 777         fw_notify("released %s\n", tgt->bus_id);
 778
 779         put_device(&tgt->unit->device);
 780         scsi_host_put(shost);
 781 }
 782
 783 static struct workqueue_struct *sbp2_wq;
 784
 785 /*
 786  * Always get the target's kref when scheduling work on one its units.
 787  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 788  */
 789 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 790 {
 791         if (queue_delayed_work(sbp2_wq, &lu->work, delay))
 792                 kref_get(&lu->tgt->kref);
 793 }
 794
 795 static void sbp2_target_put(struct sbp2_target *tgt)
 796 {
 797         kref_put(&tgt->kref, sbp2_release_target);
 798 }
 799
 800 static void sbp2_reconnect(struct work_struct *work);
 801
 802 static void sbp2_login(struct work_struct *work)
 803 {
 804         struct sbp2_logical_unit *lu =
 805                 container_of(work, struct sbp2_logical_unit, work.work);
 806         struct sbp2_target *tgt = lu->tgt;
 807         struct fw_device *device = fw_device(tgt->unit->device.parent);
 808         struct Scsi_Host *shost;
 809         struct scsi_device *sdev;
 810         struct scsi_lun eight_bytes_lun;
 811         struct sbp2_login_response response;
 812         int generation, node_id, local_node_id;
 813
 814         if (fw_device_is_shutdown(device))
 815                 goto out;
 816
 817         generation    = device->generation;
 818         smp_rmb();    /* node_id must not be older than generation */
 819         node_id       = device->node_id;
 820         local_node_id = device->card->node_id;
 821
 822         /* If this is a re-login attempt, log out, or we might be rejected. */
 823         if (lu->sdev)
 824                 sbp2_send_management_orb(lu, device->node_id, generation,
 825                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 826
 827         if (sbp2_send_management_orb(lu, node_id, generation,
 828                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 829                 if (lu->retries++ < 5) {
 830                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 831                 } else {
 832                         fw_error("%s: failed to login to LUN %04x\n",
 833                                  tgt->bus_id, lu->lun);
 834                         /* Let any waiting I/O fail from now on. */
 835                         sbp2_unblock(lu->tgt);
 836                 }
 837                 goto out;
 838         }
 839
 840         tgt->node_id      = node_id;
 841         tgt->address_high = local_node_id << 16;
 842         sbp2_set_generation(lu, generation);
 843
 844         /* Get command block agent offset and login id. */
 845         lu->command_block_agent_address =
 846                 ((u64) (response.command_block_agent.high & 0xffff) << 32) |
 847                 response.command_block_agent.low;
 848         lu->login_id = LOGIN_RESPONSE_GET_LOGIN_ID(response);
 849
 850         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 851                   tgt->bus_id, lu->lun, lu->retries);
 852
 853 #if 0
 854         /* FIXME: The linux1394 sbp2 does this last step. */
 855         sbp2_set_busy_timeout(scsi_id);
 856 #endif
 857
 858         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 859         sbp2_agent_reset(lu);
 860
 861         /* This was a re-login. */
 862         if (lu->sdev) {
 863                 sbp2_cancel_orbs(lu);
 864                 sbp2_conditionally_unblock(lu);
 865                 goto out;
 866         }
 867
 868         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 869                 ssleep(SBP2_INQUIRY_DELAY);
 870
 871         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 872         eight_bytes_lun.scsi_lun[0] = (lu->lun >> 8) & 0xff;
 873         eight_bytes_lun.scsi_lun[1] = lu->lun & 0xff;
 874         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 875
 876         sdev = __scsi_add_device(shost, 0, 0,
 877                                  scsilun_to_int(&eight_bytes_lun), lu);
 878         /*
 879          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 880          * Therefore __scsi_add_device() will get into trouble if a bus reset
 881          * happens in parallel.  It will either fail or leave us with an
 882          * unusable sdev.  As a workaround we check for this and retry the
 883          * whole login and SCSI probing.
 884          */
 885
 886         /* Reported error during __scsi_add_device() */
 887         if (IS_ERR(sdev))
 888                 goto out_logout_login;
 889
 890         /* Unreported error during __scsi_add_device() */
 891         smp_rmb(); /* get current card generation */
 892         if (generation != device->card->generation) {
 893                 scsi_remove_device(sdev);
 894                 scsi_device_put(sdev);
 895                 goto out_logout_login;
 896         }
 897
 898         /* No error during __scsi_add_device() */
 899         lu->sdev = sdev;
 900         sbp2_allow_block(lu);
 901         goto out;
 902
 903  out_logout_login:
 904         smp_rmb(); /* generation may have changed */
 905         generation = device->generation;
 906         smp_rmb(); /* node_id must not be older than generation */
 907
 908         sbp2_send_management_orb(lu, device->node_id, generation,
 909                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 910         /*
 911          * If a bus reset happened, sbp2_update will have requeued
 912          * lu->work already.  Reset the work from reconnect to login.
 913          */
 914         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 915  out:
 916         sbp2_target_put(tgt);
 917 }
 918
 919 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 920 {
 921         struct sbp2_logical_unit *lu;
 922
 923         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 924         if (!lu)
 925                 return -ENOMEM;
 926
 927         lu->address_handler.length           = 0x100;
 928         lu->address_handler.address_callback = sbp2_status_write;
 929         lu->address_handler.callback_data    = lu;
 930
 931         if (fw_core_add_address_handler(&lu->address_handler,
 932                                         &fw_high_memory_region) < 0) {
 933                 kfree(lu);
 934                 return -ENOMEM;
 935         }
 936
 937         lu->tgt  = tgt;
 938         lu->sdev = NULL;
 939         lu->lun  = lun_entry & 0xffff;
 940         lu->retries = 0;
 941         lu->blocked = false;
 942         ++tgt->dont_block;
 943         INIT_LIST_HEAD(&lu->orb_list);
 944         INIT_DELAYED_WORK(&lu->work, sbp2_login);
 945
 946         list_add_tail(&lu->link, &tgt->lu_list);
 947         return 0;
 948 }
 949
 950 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
 951 {
 952         struct fw_csr_iterator ci;
 953         int key, value;
 954
 955         fw_csr_iterator_init(&ci, directory);
 956         while (fw_csr_iterator_next(&ci, &key, &value))
 957                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
 958                     sbp2_add_logical_unit(tgt, value) < 0)
 959                         return -ENOMEM;
 960         return 0;
 961 }
 962
 963 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
 964                               u32 *model, u32 *firmware_revision)
 965 {
 966         struct fw_csr_iterator ci;
 967         int key, value;
 968         unsigned int timeout;
 969
 970         fw_csr_iterator_init(&ci, directory);
 971         while (fw_csr_iterator_next(&ci, &key, &value)) {
 972                 switch (key) {
 973
 974                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
 975                         tgt->management_agent_address =
 976                                         CSR_REGISTER_BASE + 4 * value;
 977                         break;
 978
 979                 case CSR_DIRECTORY_ID:
 980                         tgt->directory_id = value;
 981                         break;
 982
 983                 case CSR_MODEL:
 984                         *model = value;
 985                         break;
 986
 987                 case SBP2_CSR_FIRMWARE_REVISION:
 988                         *firmware_revision = value;
 989                         break;
 990
 991                 case SBP2_CSR_UNIT_CHARACTERISTICS:
 992                         /* the timeout value is stored in 500ms units */
 993                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
 994                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
 995                         tgt->mgt_orb_timeout =
 996                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
 997
 998                         if (timeout > tgt->mgt_orb_timeout)
 999                                 fw_notify("%s: config rom contains %ds "
1000                                           "management ORB timeout, limiting "
1001                                           "to %ds\n", tgt->bus_id,
1002                                           timeout / 1000,
1003                                           tgt->mgt_orb_timeout / 1000);
1004                         break;
1005
1006                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1007                         if (sbp2_add_logical_unit(tgt, value) < 0)
1008                                 return -ENOMEM;
1009                         break;
1010
1011                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1012                         if (sbp2_scan_logical_unit_dir(tgt, ci.p + value) < 0)
1013                                 return -ENOMEM;
1014                         break;
1015                 }
1016         }
1017         return 0;
1018 }
1019
1020 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1021                                   u32 firmware_revision)
1022 {
1023         int i;
1024         unsigned int w = sbp2_param_workarounds;
1025
1026         if (w)
1027                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1028                           "if you need the workarounds parameter for %s\n",
1029                           tgt->bus_id);
1030
1031         if (w & SBP2_WORKAROUND_OVERRIDE)
1032                 goto out;
1033
1034         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1035
1036                 if (sbp2_workarounds_table[i].firmware_revision !=
1037                     (firmware_revision & 0xffffff00))
1038                         continue;
1039
1040                 if (sbp2_workarounds_table[i].model != model &&
1041                     sbp2_workarounds_table[i].model != ~0)
1042                         continue;
1043
1044                 w |= sbp2_workarounds_table[i].workarounds;
1045                 break;
1046         }
1047  out:
1048         if (w)
1049                 fw_notify("Workarounds for %s: 0x%x "
1050                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1051                           tgt->bus_id, w, firmware_revision, model);
1052         tgt->workarounds = w;
1053 }
1054
1055 static struct scsi_host_template scsi_driver_template;
1056
1057 static int sbp2_probe(struct device *dev)
1058 {
1059         struct fw_unit *unit = fw_unit(dev);
1060         struct fw_device *device = fw_device(unit->device.parent);
1061         struct sbp2_target *tgt;
1062         struct sbp2_logical_unit *lu;
1063         struct Scsi_Host *shost;
1064         u32 model, firmware_revision;
1065
1066         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1067         if (shost == NULL)
1068                 return -ENOMEM;
1069
1070         tgt = (struct sbp2_target *)shost->hostdata;
1071         unit->device.driver_data = tgt;
1072         tgt->unit = unit;
1073         kref_init(&tgt->kref);
1074         INIT_LIST_HEAD(&tgt->lu_list);
1075         tgt->bus_id = unit->device.bus_id;
1076
1077         if (fw_device_enable_phys_dma(device) < 0)
1078                 goto fail_shost_put;
1079
1080         if (scsi_add_host(shost, &unit->device) < 0)
1081                 goto fail_shost_put;
1082
1083         /* Initialize to values that won't match anything in our table. */
1084         firmware_revision = 0xff000000;
1085         model = 0xff000000;
1086
1087         /* implicit directory ID */
1088         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1089                              + CSR_CONFIG_ROM) & 0xffffff;
1090
1091         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1092                                &firmware_revision) < 0)
1093                 goto fail_tgt_put;
1094
1095         sbp2_init_workarounds(tgt, model, firmware_revision);
1096
1097         get_device(&unit->device);
1098
1099         /* Do the login in a workqueue so we can easily reschedule retries. */
1100         list_for_each_entry(lu, &tgt->lu_list, link)
1101                 sbp2_queue_work(lu, 0);
1102         return 0;
1103
1104  fail_tgt_put:
1105         sbp2_target_put(tgt);
1106         return -ENOMEM;
1107
1108  fail_shost_put:
1109         scsi_host_put(shost);
1110         return -ENOMEM;
1111 }
1112
1113 static int sbp2_remove(struct device *dev)
1114 {
1115         struct fw_unit *unit = fw_unit(dev);
1116         struct sbp2_target *tgt = unit->device.driver_data;
1117
1118         sbp2_target_put(tgt);
1119         return 0;
1120 }
1121
1122 static void sbp2_reconnect(struct work_struct *work)
1123 {
1124         struct sbp2_logical_unit *lu =
1125                 container_of(work, struct sbp2_logical_unit, work.work);
1126         struct sbp2_target *tgt = lu->tgt;
1127         struct fw_device *device = fw_device(tgt->unit->device.parent);
1128         int generation, node_id, local_node_id;
1129
1130         if (fw_device_is_shutdown(device))
1131                 goto out;
1132
1133         generation    = device->generation;
1134         smp_rmb();    /* node_id must not be older than generation */
1135         node_id       = device->node_id;
1136         local_node_id = device->card->node_id;
1137
1138         if (sbp2_send_management_orb(lu, node_id, generation,
1139                                      SBP2_RECONNECT_REQUEST,
1140                                      lu->login_id, NULL) < 0) {
1141                 /*
1142                  * If reconnect was impossible even though we are in the
1143                  * current generation, fall back and try to log in again.
1144                  *
1145                  * We could check for "Function rejected" status, but
1146                  * looking at the bus generation as simpler and more general.
1147                  */
1148                 smp_rmb(); /* get current card generation */
1149                 if (generation == device->card->generation ||
1150                     lu->retries++ >= 5) {
1151                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1152                         lu->retries = 0;
1153                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1154                 }
1155                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1156                 goto out;
1157         }
1158
1159         tgt->node_id      = node_id;
1160         tgt->address_high = local_node_id << 16;
1161         sbp2_set_generation(lu, generation);
1162
1163         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1164                   tgt->bus_id, lu->lun, lu->retries);
1165
1166         sbp2_agent_reset(lu);
1167         sbp2_cancel_orbs(lu);
1168         sbp2_conditionally_unblock(lu);
1169  out:
1170         sbp2_target_put(tgt);
1171 }
1172
1173 static void sbp2_update(struct fw_unit *unit)
1174 {
1175         struct sbp2_target *tgt = unit->device.driver_data;
1176         struct sbp2_logical_unit *lu;
1177
1178         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1179
1180         /*
1181          * Fw-core serializes sbp2_update() against sbp2_remove().
1182          * Iteration over tgt->lu_list is therefore safe here.
1183          */
1184         list_for_each_entry(lu, &tgt->lu_list, link) {
1185                 sbp2_conditionally_block(lu);
1186                 lu->retries = 0;
1187                 sbp2_queue_work(lu, 0);
1188         }
1189 }
1190
1191 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1192 #define SBP2_SW_VERSION_ENTRY   0x00010483
1193
1194 static const struct fw_device_id sbp2_id_table[] = {
1195         {
1196                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1197                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1198                 .version      = SBP2_SW_VERSION_ENTRY,
1199         },
1200         { }
1201 };
1202
1203 static struct fw_driver sbp2_driver = {
1204         .driver   = {
1205                 .owner  = THIS_MODULE,
1206                 .name   = sbp2_driver_name,
1207                 .bus    = &fw_bus_type,
1208                 .probe  = sbp2_probe,
1209                 .remove = sbp2_remove,
1210         },
1211         .update   = sbp2_update,
1212         .id_table = sbp2_id_table,
1213 };
1214
1215 static unsigned int
1216 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1217 {
1218         int sam_status;
1219
1220         sense_data[0] = 0x70;
1221         sense_data[1] = 0x0;
1222         sense_data[2] = sbp2_status[1];
1223         sense_data[3] = sbp2_status[4];
1224         sense_data[4] = sbp2_status[5];
1225         sense_data[5] = sbp2_status[6];
1226         sense_data[6] = sbp2_status[7];
1227         sense_data[7] = 10;
1228         sense_data[8] = sbp2_status[8];
1229         sense_data[9] = sbp2_status[9];
1230         sense_data[10] = sbp2_status[10];
1231         sense_data[11] = sbp2_status[11];
1232         sense_data[12] = sbp2_status[2];
1233         sense_data[13] = sbp2_status[3];
1234         sense_data[14] = sbp2_status[12];
1235         sense_data[15] = sbp2_status[13];
1236
1237         sam_status = sbp2_status[0] & 0x3f;
1238
1239         switch (sam_status) {
1240         case SAM_STAT_GOOD:
1241         case SAM_STAT_CHECK_CONDITION:
1242         case SAM_STAT_CONDITION_MET:
1243         case SAM_STAT_BUSY:
1244         case SAM_STAT_RESERVATION_CONFLICT:
1245         case SAM_STAT_COMMAND_TERMINATED:
1246                 return DID_OK << 16 | sam_status;
1247
1248         default:
1249                 return DID_ERROR << 16;
1250         }
1251 }
1252
1253 static void
1254 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1255 {
1256         struct sbp2_command_orb *orb =
1257                 container_of(base_orb, struct sbp2_command_orb, base);
1258         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1259         int result;
1260
1261         if (status != NULL) {
1262                 if (STATUS_GET_DEAD(*status))
1263                         sbp2_agent_reset_no_wait(orb->lu);
1264
1265                 switch (STATUS_GET_RESPONSE(*status)) {
1266                 case SBP2_STATUS_REQUEST_COMPLETE:
1267                         result = DID_OK << 16;
1268                         break;
1269                 case SBP2_STATUS_TRANSPORT_FAILURE:
1270                         result = DID_BUS_BUSY << 16;
1271                         break;
1272                 case SBP2_STATUS_ILLEGAL_REQUEST:
1273                 case SBP2_STATUS_VENDOR_DEPENDENT:
1274                 default:
1275                         result = DID_ERROR << 16;
1276                         break;
1277                 }
1278
1279                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1280                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1281                                                            orb->cmd->sense_buffer);
1282         } else {
1283                 /*
1284                  * If the orb completes with status == NULL, something
1285                  * went wrong, typically a bus reset happened mid-orb
1286                  * or when sending the write (less likely).
1287                  */
1288                 result = DID_BUS_BUSY << 16;
1289                 sbp2_conditionally_block(orb->lu);
1290         }
1291
1292         dma_unmap_single(device->card->device, orb->base.request_bus,
1293                          sizeof(orb->request), DMA_TO_DEVICE);
1294
1295         if (scsi_sg_count(orb->cmd) > 0)
1296                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1297                              scsi_sg_count(orb->cmd),
1298                              orb->cmd->sc_data_direction);
1299
1300         if (orb->page_table_bus != 0)
1301                 dma_unmap_single(device->card->device, orb->page_table_bus,
1302                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1303
1304         orb->cmd->result = result;
1305         orb->done(orb->cmd);
1306 }
1307
1308 static int
1309 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1310                      struct sbp2_logical_unit *lu)
1311 {
1312         struct scatterlist *sg;
1313         int sg_len, l, i, j, count;
1314         dma_addr_t sg_addr;
1315
1316         sg = scsi_sglist(orb->cmd);
1317         count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1318                            orb->cmd->sc_data_direction);
1319         if (count == 0)
1320                 goto fail;
1321
1322         /*
1323          * Handle the special case where there is only one element in
1324          * the scatter list by converting it to an immediate block
1325          * request. This is also a workaround for broken devices such
1326          * as the second generation iPod which doesn't support page
1327          * tables.
1328          */
1329         if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) {
1330                 orb->request.data_descriptor.high = lu->tgt->address_high;
1331                 orb->request.data_descriptor.low  = sg_dma_address(sg);
1332                 orb->request.misc |= COMMAND_ORB_DATA_SIZE(sg_dma_len(sg));
1333                 return 0;
1334         }
1335
1336         /*
1337          * Convert the scatterlist to an sbp2 page table.  If any
1338          * scatterlist entries are too big for sbp2, we split them as we
1339          * go.  Even if we ask the block I/O layer to not give us sg
1340          * elements larger than 65535 bytes, some IOMMUs may merge sg elements
1341          * during DMA mapping, and Linux currently doesn't prevent this.
1342          */
1343         for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) {
1344                 sg_len = sg_dma_len(sg);
1345                 sg_addr = sg_dma_address(sg);
1346                 while (sg_len) {
1347                         /* FIXME: This won't get us out of the pinch. */
1348                         if (unlikely(j >= ARRAY_SIZE(orb->page_table))) {
1349                                 fw_error("page table overflow\n");
1350                                 goto fail_page_table;
1351                         }
1352                         l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH);
1353                         orb->page_table[j].low = sg_addr;
1354                         orb->page_table[j].high = (l << 16);
1355                         sg_addr += l;
1356                         sg_len -= l;
1357                         j++;
1358                 }
1359         }
1360
1361         fw_memcpy_to_be32(orb->page_table, orb->page_table,
1362                           sizeof(orb->page_table[0]) * j);
1363         orb->page_table_bus =
1364                 dma_map_single(device->card->device, orb->page_table,
1365                                sizeof(orb->page_table), DMA_TO_DEVICE);
1366         if (dma_mapping_error(orb->page_table_bus))
1367                 goto fail_page_table;
1368
1369         /*
1370          * The data_descriptor pointer is the one case where we need
1371          * to fill in the node ID part of the address.  All other
1372          * pointers assume that the data referenced reside on the
1373          * initiator (i.e. us), but data_descriptor can refer to data
1374          * on other nodes so we need to put our ID in descriptor.high.
1375          */
1376         orb->request.data_descriptor.high = lu->tgt->address_high;
1377         orb->request.data_descriptor.low  = orb->page_table_bus;
1378         orb->request.misc |=
1379                 COMMAND_ORB_PAGE_TABLE_PRESENT |
1380                 COMMAND_ORB_DATA_SIZE(j);
1381
1382         return 0;
1383
1384  fail_page_table:
1385         dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1386                      orb->cmd->sc_data_direction);
1387  fail:
1388         return -ENOMEM;
1389 }
1390
1391 /* SCSI stack integration */
1392
1393 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1394 {
1395         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1396         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1397         struct sbp2_command_orb *orb;
1398         unsigned int max_payload;
1399         int retval = SCSI_MLQUEUE_HOST_BUSY;
1400
1401         /*
1402          * Bidirectional commands are not yet implemented, and unknown
1403          * transfer direction not handled.
1404          */
1405         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1406                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1407                 cmd->result = DID_ERROR << 16;
1408                 done(cmd);
1409                 return 0;
1410         }
1411
1412         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1413         if (orb == NULL) {
1414                 fw_notify("failed to alloc orb\n");
1415                 return SCSI_MLQUEUE_HOST_BUSY;
1416         }
1417
1418         /* Initialize rcode to something not RCODE_COMPLETE. */
1419         orb->base.rcode = -1;
1420         kref_init(&orb->base.kref);
1421
1422         orb->lu   = lu;
1423         orb->done = done;
1424         orb->cmd  = cmd;
1425
1426         orb->request.next.high   = SBP2_ORB_NULL;
1427         orb->request.next.low    = 0x0;
1428         /*
1429          * At speed 100 we can do 512 bytes per packet, at speed 200,
1430          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1431          * specifies the max payload size as 2 ^ (max_payload + 2), so
1432          * if we set this to max_speed + 7, we get the right value.
1433          */
1434         max_payload = min(device->max_speed + 7,
1435                           device->card->max_receive - 1);
1436         orb->request.misc =
1437                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1438                 COMMAND_ORB_SPEED(device->max_speed) |
1439                 COMMAND_ORB_NOTIFY;
1440
1441         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1442                 orb->request.misc |=
1443                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_FROM_MEDIA);
1444         else if (cmd->sc_data_direction == DMA_TO_DEVICE)
1445                 orb->request.misc |=
1446                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_TO_MEDIA);
1447
1448         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1449                 goto out;
1450
1451         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
1452
1453         memset(orb->request.command_block,
1454                0, sizeof(orb->request.command_block));
1455         memcpy(orb->request.command_block, cmd->cmnd, COMMAND_SIZE(*cmd->cmnd));
1456
1457         orb->base.callback = complete_command_orb;
1458         orb->base.request_bus =
1459                 dma_map_single(device->card->device, &orb->request,
1460                                sizeof(orb->request), DMA_TO_DEVICE);
1461         if (dma_mapping_error(orb->base.request_bus))
1462                 goto out;
1463
1464         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, lu->generation,
1465                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1466         retval = 0;
1467  out:
1468         kref_put(&orb->base.kref, free_orb);
1469         return retval;
1470 }
1471
1472 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1473 {
1474         struct sbp2_logical_unit *lu = sdev->hostdata;
1475
1476         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1477         if (!lu)
1478                 return -ENOSYS;
1479
1480         sdev->allow_restart = 1;
1481
1482         /*
1483          * Update the dma alignment (minimum alignment requirements for
1484          * start and end of DMA transfers) to be a sector
1485          */
1486         blk_queue_update_dma_alignment(sdev->request_queue, 511);
1487
1488         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1489                 sdev->inquiry_len = 36;
1490
1491         return 0;
1492 }
1493
1494 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1495 {
1496         struct sbp2_logical_unit *lu = sdev->hostdata;
1497
1498         sdev->use_10_for_rw = 1;
1499
1500         if (sdev->type == TYPE_ROM)
1501                 sdev->use_10_for_ms = 1;
1502
1503         if (sdev->type == TYPE_DISK &&
1504             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1505                 sdev->skip_ms_page_8 = 1;
1506
1507         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1508                 sdev->fix_capacity = 1;
1509
1510         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1511                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1512
1513         return 0;
1514 }
1515
1516 /*
1517  * Called by scsi stack when something has really gone wrong.  Usually
1518  * called when a command has timed-out for some reason.
1519  */
1520 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1521 {
1522         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1523
1524         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1525         sbp2_agent_reset(lu);
1526         sbp2_cancel_orbs(lu);
1527
1528         return SUCCESS;
1529 }
1530
1531 /*
1532  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1533  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1534  *
1535  * This is the concatenation of target port identifier and logical unit
1536  * identifier as per SAM-2...SAM-4 annex A.
1537  */
1538 static ssize_t
1539 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1540                             char *buf)
1541 {
1542         struct scsi_device *sdev = to_scsi_device(dev);
1543         struct sbp2_logical_unit *lu;
1544         struct fw_device *device;
1545
1546         if (!sdev)
1547                 return 0;
1548
1549         lu = sdev->hostdata;
1550         device = fw_device(lu->tgt->unit->device.parent);
1551
1552         return sprintf(buf, "%08x%08x:%06x:%04x\n",
1553                         device->config_rom[3], device->config_rom[4],
1554                         lu->tgt->directory_id, lu->lun);
1555 }
1556
1557 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1558
1559 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1560         &dev_attr_ieee1394_id,
1561         NULL
1562 };
1563
1564 static struct scsi_host_template scsi_driver_template = {
1565         .module                 = THIS_MODULE,
1566         .name                   = "SBP-2 IEEE-1394",
1567         .proc_name              = sbp2_driver_name,
1568         .queuecommand           = sbp2_scsi_queuecommand,
1569         .slave_alloc            = sbp2_scsi_slave_alloc,
1570         .slave_configure        = sbp2_scsi_slave_configure,
1571         .eh_abort_handler       = sbp2_scsi_abort,
1572         .this_id                = -1,
1573         .sg_tablesize           = SG_ALL,
1574         .use_clustering         = ENABLE_CLUSTERING,
1575         .cmd_per_lun            = 1,
1576         .can_queue              = 1,
1577         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1578 };
1579
1580 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1581 MODULE_DESCRIPTION("SCSI over IEEE1394");
1582 MODULE_LICENSE("GPL");
1583 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1584
1585 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1586 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1587 MODULE_ALIAS("sbp2");
1588 #endif
1589
1590 static int __init sbp2_init(void)
1591 {
1592         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1593         if (!sbp2_wq)
1594                 return -ENOMEM;
1595
1596         return driver_register(&sbp2_driver.driver);
1597 }
1598
1599 static void __exit sbp2_cleanup(void)
1600 {
1601         driver_unregister(&sbp2_driver.driver);
1602         destroy_workqueue(sbp2_wq);
1603 }
1604
1605 module_init(sbp2_init);
1606 module_exit(sbp2_cleanup);