drivers/firewire/sbp2.c

   1 /*
   2  * SBP2 driver (SCSI over IEEE1394)
   3  *
   4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22  * The basic structure of this driver is based on the old storage driver,
  23  * drivers/ieee1394/sbp2.c, originally written by
  24  *     James Goodwin <jamesg@filanet.com>
  25  * with later contributions and ongoing maintenance from
  26  *     Ben Collins <bcollins@debian.org>,
  27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  28  * and many others.
  29  */
  30
  31 #include <linux/blkdev.h>
  32 #include <linux/bug.h>
  33 #include <linux/completion.h>
  34 #include <linux/delay.h>
  35 #include <linux/device.h>
  36 #include <linux/dma-mapping.h>
  37 #include <linux/firewire.h>
  38 #include <linux/firewire-constants.h>
  39 #include <linux/init.h>
  40 #include <linux/jiffies.h>
  41 #include <linux/kernel.h>
  42 #include <linux/kref.h>
  43 #include <linux/list.h>
  44 #include <linux/mod_devicetable.h>
  45 #include <linux/module.h>
  46 #include <linux/moduleparam.h>
  47 #include <linux/scatterlist.h>
  48 #include <linux/slab.h>
  49 #include <linux/spinlock.h>
  50 #include <linux/string.h>
  51 #include <linux/stringify.h>
  52 #include <linux/workqueue.h>
  53
  54 #include <asm/byteorder.h>
  55 #include <asm/system.h>
  56
  57 #include <scsi/scsi.h>
  58 #include <scsi/scsi_cmnd.h>
  59 #include <scsi/scsi_device.h>
  60 #include <scsi/scsi_host.h>
  61
  62 /*
  63  * So far only bridges from Oxford Semiconductor are known to support
  64  * concurrent logins. Depending on firmware, four or two concurrent logins
  65  * are possible on OXFW911 and newer Oxsemi bridges.
  66  *
  67  * Concurrent logins are useful together with cluster filesystems.
  68  */
  69 static int sbp2_param_exclusive_login = 1;
  70 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  71 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  72                  "(default = Y, use N for concurrent initiators)");
  73
  74 /*
  75  * Flags for firmware oddities
  76  *
  77  * - 128kB max transfer
  78  *   Limit transfer size. Necessary for some old bridges.
  79  *
  80  * - 36 byte inquiry
  81  *   When scsi_mod probes the device, let the inquiry command look like that
  82  *   from MS Windows.
  83  *
  84  * - skip mode page 8
  85  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  86  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  87  *
  88  * - fix capacity
  89  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  90  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  91  *   Don't use this with devices which don't have this bug.
  92  *
  93  * - delay inquiry
  94  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  95  *
  96  * - power condition
  97  *   Set the power condition field in the START STOP UNIT commands sent by
  98  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  99  *   Some disks need this to spin down or to resume properly.
 100  *
 101  * - override internal blacklist
 102  *   Instead of adding to the built-in blacklist, use only the workarounds
 103  *   specified in the module load parameter.
 104  *   Useful if a blacklist entry interfered with a non-broken device.
 105  */
 106 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 107 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 108 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 109 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 110 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 111 #define SBP2_INQUIRY_DELAY              12
 112 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 113 #define SBP2_WORKAROUND_OVERRIDE        0x100
 114
 115 static int sbp2_param_workarounds;
 116 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 117 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 118         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 119         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 120         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 121         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 122         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 123         ", set power condition in start stop unit = "
 124                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 125         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 126         ", or a combination)");
 127
 128 /* I don't know why the SCSI stack doesn't define something like this... */
 129 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
 130
 131 static const char sbp2_driver_name[] = "sbp2";
 132
 133 /*
 134  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 135  * and one struct scsi_device per sbp2_logical_unit.
 136  */
 137 struct sbp2_logical_unit {
 138         struct sbp2_target *tgt;
 139         struct list_head link;
 140         struct fw_address_handler address_handler;
 141         struct list_head orb_list;
 142
 143         u64 command_block_agent_address;
 144         u16 lun;
 145         int login_id;
 146
 147         /*
 148          * The generation is updated once we've logged in or reconnected
 149          * to the logical unit.  Thus, I/O to the device will automatically
 150          * fail and get retried if it happens in a window where the device
 151          * is not ready, e.g. after a bus reset but before we reconnect.
 152          */
 153         int generation;
 154         int retries;
 155         struct delayed_work work;
 156         bool has_sdev;
 157         bool blocked;
 158 };
 159
 160 /*
 161  * We create one struct sbp2_target per IEEE 1212 Unit Directory
 162  * and one struct Scsi_Host per sbp2_target.
 163  */
 164 struct sbp2_target {
 165         struct kref kref;
 166         struct fw_unit *unit;
 167         const char *bus_id;
 168         struct list_head lu_list;
 169
 170         u64 management_agent_address;
 171         u64 guid;
 172         int directory_id;
 173         int node_id;
 174         int address_high;
 175         unsigned int workarounds;
 176         unsigned int mgt_orb_timeout;
 177         unsigned int max_payload;
 178
 179         int dont_block; /* counter for each logical unit */
 180         int blocked;    /* ditto */
 181 };
 182
 183 static struct fw_device *target_device(struct sbp2_target *tgt)
 184 {
 185         return fw_parent_device(tgt->unit);
 186 }
 187
 188 /* Impossible login_id, to detect logout attempt before successful login */
 189 #define INVALID_LOGIN_ID 0x10000
 190
 191 /*
 192  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
 193  * provided in the config rom. Most devices do provide a value, which
 194  * we'll use for login management orbs, but with some sane limits.
 195  */
 196 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
 197 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
 198 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
 199 #define SBP2_ORB_NULL                   0x80000000
 200 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 201 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 202
 203 /*
 204  * The default maximum s/g segment size of a FireWire controller is
 205  * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
 206  * be quadlet-aligned, we set the length limit to 0xffff & ~3.
 207  */
 208 #define SBP2_MAX_SEG_SIZE               0xfffc
 209
 210 /* Unit directory keys */
 211 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 212 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 213 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 214 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 215
 216 /* Management orb opcodes */
 217 #define SBP2_LOGIN_REQUEST              0x0
 218 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 219 #define SBP2_RECONNECT_REQUEST          0x3
 220 #define SBP2_SET_PASSWORD_REQUEST       0x4
 221 #define SBP2_LOGOUT_REQUEST             0x7
 222 #define SBP2_ABORT_TASK_REQUEST         0xb
 223 #define SBP2_ABORT_TASK_SET             0xc
 224 #define SBP2_LOGICAL_UNIT_RESET         0xe
 225 #define SBP2_TARGET_RESET_REQUEST       0xf
 226
 227 /* Offsets for command block agent registers */
 228 #define SBP2_AGENT_STATE                0x00
 229 #define SBP2_AGENT_RESET                0x04
 230 #define SBP2_ORB_POINTER                0x08
 231 #define SBP2_DOORBELL                   0x10
 232 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 233
 234 /* Status write response codes */
 235 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 236 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 237 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 238 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 239
 240 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 241 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 242 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 243 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 244 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 245 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 246 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 247 #define STATUS_GET_DATA(v)              ((v).data)
 248
 249 struct sbp2_status {
 250         u32 status;
 251         u32 orb_low;
 252         u8 data[24];
 253 };
 254
 255 struct sbp2_pointer {
 256         __be32 high;
 257         __be32 low;
 258 };
 259
 260 struct sbp2_orb {
 261         struct fw_transaction t;
 262         struct kref kref;
 263         dma_addr_t request_bus;
 264         int rcode;
 265         struct sbp2_pointer pointer;
 266         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 267         struct list_head link;
 268 };
 269
 270 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 271 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 272 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 273 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 274 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 275 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 276
 277 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 278 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 279
 280 struct sbp2_management_orb {
 281         struct sbp2_orb base;
 282         struct {
 283                 struct sbp2_pointer password;
 284                 struct sbp2_pointer response;
 285                 __be32 misc;
 286                 __be32 length;
 287                 struct sbp2_pointer status_fifo;
 288         } request;
 289         __be32 response[4];
 290         dma_addr_t response_bus;
 291         struct completion done;
 292         struct sbp2_status status;
 293 };
 294
 295 struct sbp2_login_response {
 296         __be32 misc;
 297         struct sbp2_pointer command_block_agent;
 298         __be32 reconnect_hold;
 299 };
 300 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 301 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 302 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 303 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 304 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 305 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 306 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 307 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 308
 309 struct sbp2_command_orb {
 310         struct sbp2_orb base;
 311         struct {
 312                 struct sbp2_pointer next;
 313                 struct sbp2_pointer data_descriptor;
 314                 __be32 misc;
 315                 u8 command_block[12];
 316         } request;
 317         struct scsi_cmnd *cmd;
 318         scsi_done_fn_t done;
 319         struct sbp2_logical_unit *lu;
 320
 321         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 322         dma_addr_t page_table_bus;
 323 };
 324
 325 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 326 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 327
 328 /*
 329  * List of devices with known bugs.
 330  *
 331  * The firmware_revision field, masked with 0xffff00, is the best
 332  * indicator for the type of bridge chip of a device.  It yields a few
 333  * false positives but this did not break correctly behaving devices
 334  * so far.
 335  */
 336 static const struct {
 337         u32 firmware_revision;
 338         u32 model;
 339         unsigned int workarounds;
 340 } sbp2_workarounds_table[] = {
 341         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 342                 .firmware_revision      = 0x002800,
 343                 .model                  = 0x001010,
 344                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 345                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 346                                           SBP2_WORKAROUND_POWER_CONDITION,
 347         },
 348         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 349                 .firmware_revision      = 0x002800,
 350                 .model                  = 0x000000,
 351                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
 352                                           SBP2_WORKAROUND_POWER_CONDITION,
 353         },
 354         /* Initio bridges, actually only needed for some older ones */ {
 355                 .firmware_revision      = 0x000200,
 356                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 357                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 358         },
 359         /* PL-3507 bridge with Prolific firmware */ {
 360                 .firmware_revision      = 0x012800,
 361                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 362                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 363         },
 364         /* Symbios bridge */ {
 365                 .firmware_revision      = 0xa0b800,
 366                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 367                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 368         },
 369         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 370                 .firmware_revision      = 0x002600,
 371                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 372                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 373         },
 374         /*
 375          * iPod 2nd generation: needs 128k max transfer size workaround
 376          * iPod 3rd generation: needs fix capacity workaround
 377          */
 378         {
 379                 .firmware_revision      = 0x0a2700,
 380                 .model                  = 0x000000,
 381                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 382                                           SBP2_WORKAROUND_FIX_CAPACITY,
 383         },
 384         /* iPod 4th generation */ {
 385                 .firmware_revision      = 0x0a2700,
 386                 .model                  = 0x000021,
 387                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 388         },
 389         /* iPod mini */ {
 390                 .firmware_revision      = 0x0a2700,
 391                 .model                  = 0x000022,
 392                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 393         },
 394         /* iPod mini */ {
 395                 .firmware_revision      = 0x0a2700,
 396                 .model                  = 0x000023,
 397                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 398         },
 399         /* iPod Photo */ {
 400                 .firmware_revision      = 0x0a2700,
 401                 .model                  = 0x00007e,
 402                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 403         }
 404 };
 405
 406 static void free_orb(struct kref *kref)
 407 {
 408         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 409
 410         kfree(orb);
 411 }
 412
 413 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 414                               int tcode, int destination, int source,
 415                               int generation, int speed,
 416                               unsigned long long offset,
 417                               void *payload, size_t length, void *callback_data)
 418 {
 419         struct sbp2_logical_unit *lu = callback_data;
 420         struct sbp2_orb *orb;
 421         struct sbp2_status status;
 422         size_t header_size;
 423         unsigned long flags;
 424
 425         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 426             length == 0 || length > sizeof(status)) {
 427                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 428                 return;
 429         }
 430
 431         header_size = min(length, 2 * sizeof(u32));
 432         fw_memcpy_from_be32(&status, payload, header_size);
 433         if (length > header_size)
 434                 memcpy(status.data, payload + 8, length - header_size);
 435         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 436                 fw_notify("non-orb related status write, not handled\n");
 437                 fw_send_response(card, request, RCODE_COMPLETE);
 438                 return;
 439         }
 440
 441         /* Lookup the orb corresponding to this status write. */
 442         spin_lock_irqsave(&card->lock, flags);
 443         list_for_each_entry(orb, &lu->orb_list, link) {
 444                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 445                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 446                         orb->rcode = RCODE_COMPLETE;
 447                         list_del(&orb->link);
 448                         break;
 449                 }
 450         }
 451         spin_unlock_irqrestore(&card->lock, flags);
 452
 453         if (&orb->link != &lu->orb_list)
 454                 orb->callback(orb, &status);
 455         else
 456                 fw_error("status write for unknown orb\n");
 457
 458         kref_put(&orb->kref, free_orb);
 459
 460         fw_send_response(card, request, RCODE_COMPLETE);
 461 }
 462
 463 static void complete_transaction(struct fw_card *card, int rcode,
 464                                  void *payload, size_t length, void *data)
 465 {
 466         struct sbp2_orb *orb = data;
 467         unsigned long flags;
 468
 469         /*
 470          * This is a little tricky.  We can get the status write for
 471          * the orb before we get this callback.  The status write
 472          * handler above will assume the orb pointer transaction was
 473          * successful and set the rcode to RCODE_COMPLETE for the orb.
 474          * So this callback only sets the rcode if it hasn't already
 475          * been set and only does the cleanup if the transaction
 476          * failed and we didn't already get a status write.
 477          */
 478         spin_lock_irqsave(&card->lock, flags);
 479
 480         if (orb->rcode == -1)
 481                 orb->rcode = rcode;
 482         if (orb->rcode != RCODE_COMPLETE) {
 483                 list_del(&orb->link);
 484                 spin_unlock_irqrestore(&card->lock, flags);
 485                 orb->callback(orb, NULL);
 486         } else {
 487                 spin_unlock_irqrestore(&card->lock, flags);
 488         }
 489
 490         kref_put(&orb->kref, free_orb);
 491 }
 492
 493 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 494                           int node_id, int generation, u64 offset)
 495 {
 496         struct fw_device *device = target_device(lu->tgt);
 497         unsigned long flags;
 498
 499         orb->pointer.high = 0;
 500         orb->pointer.low = cpu_to_be32(orb->request_bus);
 501
 502         spin_lock_irqsave(&device->card->lock, flags);
 503         list_add_tail(&orb->link, &lu->orb_list);
 504         spin_unlock_irqrestore(&device->card->lock, flags);
 505
 506         /* Take a ref for the orb list and for the transaction callback. */
 507         kref_get(&orb->kref);
 508         kref_get(&orb->kref);
 509
 510         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 511                         node_id, generation, device->max_speed, offset,
 512                         &orb->pointer, sizeof(orb->pointer),
 513                         complete_transaction, orb);
 514 }
 515
 516 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 517 {
 518         struct fw_device *device = target_device(lu->tgt);
 519         struct sbp2_orb *orb, *next;
 520         struct list_head list;
 521         unsigned long flags;
 522         int retval = -ENOENT;
 523
 524         INIT_LIST_HEAD(&list);
 525         spin_lock_irqsave(&device->card->lock, flags);
 526         list_splice_init(&lu->orb_list, &list);
 527         spin_unlock_irqrestore(&device->card->lock, flags);
 528
 529         list_for_each_entry_safe(orb, next, &list, link) {
 530                 retval = 0;
 531                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 532                         continue;
 533
 534                 orb->rcode = RCODE_CANCELLED;
 535                 orb->callback(orb, NULL);
 536         }
 537
 538         return retval;
 539 }
 540
 541 static void complete_management_orb(struct sbp2_orb *base_orb,
 542                                     struct sbp2_status *status)
 543 {
 544         struct sbp2_management_orb *orb =
 545                 container_of(base_orb, struct sbp2_management_orb, base);
 546
 547         if (status)
 548                 memcpy(&orb->status, status, sizeof(*status));
 549         complete(&orb->done);
 550 }
 551
 552 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 553                                     int generation, int function,
 554                                     int lun_or_login_id, void *response)
 555 {
 556         struct fw_device *device = target_device(lu->tgt);
 557         struct sbp2_management_orb *orb;
 558         unsigned int timeout;
 559         int retval = -ENOMEM;
 560
 561         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 562                 return 0;
 563
 564         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
 565         if (orb == NULL)
 566                 return -ENOMEM;
 567
 568         kref_init(&orb->base.kref);
 569         orb->response_bus =
 570                 dma_map_single(device->card->device, &orb->response,
 571                                sizeof(orb->response), DMA_FROM_DEVICE);
 572         if (dma_mapping_error(device->card->device, orb->response_bus))
 573                 goto fail_mapping_response;
 574
 575         orb->request.response.high = 0;
 576         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 577
 578         orb->request.misc = cpu_to_be32(
 579                 MANAGEMENT_ORB_NOTIFY |
 580                 MANAGEMENT_ORB_FUNCTION(function) |
 581                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 582         orb->request.length = cpu_to_be32(
 583                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 584
 585         orb->request.status_fifo.high =
 586                 cpu_to_be32(lu->address_handler.offset >> 32);
 587         orb->request.status_fifo.low  =
 588                 cpu_to_be32(lu->address_handler.offset);
 589
 590         if (function == SBP2_LOGIN_REQUEST) {
 591                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 592                 orb->request.misc |= cpu_to_be32(
 593                         MANAGEMENT_ORB_RECONNECT(2) |
 594                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 595                 timeout = lu->tgt->mgt_orb_timeout;
 596         } else {
 597                 timeout = SBP2_ORB_TIMEOUT;
 598         }
 599
 600         init_completion(&orb->done);
 601         orb->base.callback = complete_management_orb;
 602
 603         orb->base.request_bus =
 604                 dma_map_single(device->card->device, &orb->request,
 605                                sizeof(orb->request), DMA_TO_DEVICE);
 606         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 607                 goto fail_mapping_request;
 608
 609         sbp2_send_orb(&orb->base, lu, node_id, generation,
 610                       lu->tgt->management_agent_address);
 611
 612         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 613
 614         retval = -EIO;
 615         if (sbp2_cancel_orbs(lu) == 0) {
 616                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
 617                          lu->tgt->bus_id, orb->base.rcode);
 618                 goto out;
 619         }
 620
 621         if (orb->base.rcode != RCODE_COMPLETE) {
 622                 fw_error("%s: management write failed, rcode 0x%02x\n",
 623                          lu->tgt->bus_id, orb->base.rcode);
 624                 goto out;
 625         }
 626
 627         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 628             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 629                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
 630                          STATUS_GET_RESPONSE(orb->status),
 631                          STATUS_GET_SBP_STATUS(orb->status));
 632                 goto out;
 633         }
 634
 635         retval = 0;
 636  out:
 637         dma_unmap_single(device->card->device, orb->base.request_bus,
 638                          sizeof(orb->request), DMA_TO_DEVICE);
 639  fail_mapping_request:
 640         dma_unmap_single(device->card->device, orb->response_bus,
 641                          sizeof(orb->response), DMA_FROM_DEVICE);
 642  fail_mapping_response:
 643         if (response)
 644                 memcpy(response, orb->response, sizeof(orb->response));
 645         kref_put(&orb->base.kref, free_orb);
 646
 647         return retval;
 648 }
 649
 650 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 651 {
 652         struct fw_device *device = target_device(lu->tgt);
 653         __be32 d = 0;
 654
 655         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 656                            lu->tgt->node_id, lu->generation, device->max_speed,
 657                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 658                            &d, sizeof(d));
 659 }
 660
 661 static void complete_agent_reset_write_no_wait(struct fw_card *card,
 662                 int rcode, void *payload, size_t length, void *data)
 663 {
 664         kfree(data);
 665 }
 666
 667 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 668 {
 669         struct fw_device *device = target_device(lu->tgt);
 670         struct fw_transaction *t;
 671         static __be32 d;
 672
 673         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 674         if (t == NULL)
 675                 return;
 676
 677         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 678                         lu->tgt->node_id, lu->generation, device->max_speed,
 679                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 680                         &d, sizeof(d), complete_agent_reset_write_no_wait, t);
 681 }
 682
 683 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 684 {
 685         /*
 686          * We may access dont_block without taking card->lock here:
 687          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 688          * are currently serialized against each other.
 689          * And a wrong result in sbp2_conditionally_block()'s access of
 690          * dont_block is rather harmless, it simply misses its first chance.
 691          */
 692         --lu->tgt->dont_block;
 693 }
 694
 695 /*
 696  * Blocks lu->tgt if all of the following conditions are met:
 697  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 698  *     logical units have been finished (indicated by dont_block == 0).
 699  *   - lu->generation is stale.
 700  *
 701  * Note, scsi_block_requests() must be called while holding card->lock,
 702  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 703  * unblock the target.
 704  */
 705 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 706 {
 707         struct sbp2_target *tgt = lu->tgt;
 708         struct fw_card *card = target_device(tgt)->card;
 709         struct Scsi_Host *shost =
 710                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 711         unsigned long flags;
 712
 713         spin_lock_irqsave(&card->lock, flags);
 714         if (!tgt->dont_block && !lu->blocked &&
 715             lu->generation != card->generation) {
 716                 lu->blocked = true;
 717                 if (++tgt->blocked == 1)
 718                         scsi_block_requests(shost);
 719         }
 720         spin_unlock_irqrestore(&card->lock, flags);
 721 }
 722
 723 /*
 724  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 725  * Note, it is harmless to run scsi_unblock_requests() outside the
 726  * card->lock protected section.  On the other hand, running it inside
 727  * the section might clash with shost->host_lock.
 728  */
 729 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 730 {
 731         struct sbp2_target *tgt = lu->tgt;
 732         struct fw_card *card = target_device(tgt)->card;
 733         struct Scsi_Host *shost =
 734                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 735         unsigned long flags;
 736         bool unblock = false;
 737
 738         spin_lock_irqsave(&card->lock, flags);
 739         if (lu->blocked && lu->generation == card->generation) {
 740                 lu->blocked = false;
 741                 unblock = --tgt->blocked == 0;
 742         }
 743         spin_unlock_irqrestore(&card->lock, flags);
 744
 745         if (unblock)
 746                 scsi_unblock_requests(shost);
 747 }
 748
 749 /*
 750  * Prevents future blocking of tgt and unblocks it.
 751  * Note, it is harmless to run scsi_unblock_requests() outside the
 752  * card->lock protected section.  On the other hand, running it inside
 753  * the section might clash with shost->host_lock.
 754  */
 755 static void sbp2_unblock(struct sbp2_target *tgt)
 756 {
 757         struct fw_card *card = target_device(tgt)->card;
 758         struct Scsi_Host *shost =
 759                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 760         unsigned long flags;
 761
 762         spin_lock_irqsave(&card->lock, flags);
 763         ++tgt->dont_block;
 764         spin_unlock_irqrestore(&card->lock, flags);
 765
 766         scsi_unblock_requests(shost);
 767 }
 768
 769 static int sbp2_lun2int(u16 lun)
 770 {
 771         struct scsi_lun eight_bytes_lun;
 772
 773         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 774         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 775         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 776
 777         return scsilun_to_int(&eight_bytes_lun);
 778 }
 779
 780 static void sbp2_release_target(struct kref *kref)
 781 {
 782         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
 783         struct sbp2_logical_unit *lu, *next;
 784         struct Scsi_Host *shost =
 785                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 786         struct scsi_device *sdev;
 787         struct fw_device *device = target_device(tgt);
 788
 789         /* prevent deadlocks */
 790         sbp2_unblock(tgt);
 791
 792         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
 793                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
 794                 if (sdev) {
 795                         scsi_remove_device(sdev);
 796                         scsi_device_put(sdev);
 797                 }
 798                 if (lu->login_id != INVALID_LOGIN_ID) {
 799                         int generation, node_id;
 800                         /*
 801                          * tgt->node_id may be obsolete here if we failed
 802                          * during initial login or after a bus reset where
 803                          * the topology changed.
 804                          */
 805                         generation = device->generation;
 806                         smp_rmb(); /* node_id vs. generation */
 807                         node_id    = device->node_id;
 808                         sbp2_send_management_orb(lu, node_id, generation,
 809                                                  SBP2_LOGOUT_REQUEST,
 810                                                  lu->login_id, NULL);
 811                 }
 812                 fw_core_remove_address_handler(&lu->address_handler);
 813                 list_del(&lu->link);
 814                 kfree(lu);
 815         }
 816         scsi_remove_host(shost);
 817         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
 818
 819         fw_unit_put(tgt->unit);
 820         scsi_host_put(shost);
 821         fw_device_put(device);
 822 }
 823
 824 static struct workqueue_struct *sbp2_wq;
 825
 826 static void sbp2_target_put(struct sbp2_target *tgt)
 827 {
 828         kref_put(&tgt->kref, sbp2_release_target);
 829 }
 830
 831 /*
 832  * Always get the target's kref when scheduling work on one its units.
 833  * Each workqueue job is responsible to call sbp2_target_put() upon return.
 834  */
 835 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 836 {
 837         kref_get(&lu->tgt->kref);
 838         if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
 839                 sbp2_target_put(lu->tgt);
 840 }
 841
 842 /*
 843  * Write retransmit retry values into the BUSY_TIMEOUT register.
 844  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 845  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 846  *   saner value after logging into the device.
 847  * - The dual-phase retry protocol is optional to implement, and if not
 848  *   supported, writes to the dual-phase portion of the register will be
 849  *   ignored. We try to write the original 1394-1995 default here.
 850  * - In the case of devices that are also SBP-3-compliant, all writes are
 851  *   ignored, as the register is read-only, but contains single-phase retry of
 852  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 853  *   write attempt is safe and yields more consistent behavior for all devices.
 854  *
 855  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 856  * and section 6.4 of the SBP-3 spec for further details.
 857  */
 858 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 859 {
 860         struct fw_device *device = target_device(lu->tgt);
 861         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 862
 863         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 864                            lu->tgt->node_id, lu->generation, device->max_speed,
 865                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
 866                            &d, sizeof(d));
 867 }
 868
 869 static void sbp2_reconnect(struct work_struct *work);
 870
 871 static void sbp2_login(struct work_struct *work)
 872 {
 873         struct sbp2_logical_unit *lu =
 874                 container_of(work, struct sbp2_logical_unit, work.work);
 875         struct sbp2_target *tgt = lu->tgt;
 876         struct fw_device *device = target_device(tgt);
 877         struct Scsi_Host *shost;
 878         struct scsi_device *sdev;
 879         struct sbp2_login_response response;
 880         int generation, node_id, local_node_id;
 881
 882         if (fw_device_is_shutdown(device))
 883                 goto out;
 884
 885         generation    = device->generation;
 886         smp_rmb();    /* node IDs must not be older than generation */
 887         node_id       = device->node_id;
 888         local_node_id = device->card->node_id;
 889
 890         /* If this is a re-login attempt, log out, or we might be rejected. */
 891         if (lu->has_sdev)
 892                 sbp2_send_management_orb(lu, device->node_id, generation,
 893                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 894
 895         if (sbp2_send_management_orb(lu, node_id, generation,
 896                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 897                 if (lu->retries++ < 5) {
 898                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 899                 } else {
 900                         fw_error("%s: failed to login to LUN %04x\n",
 901                                  tgt->bus_id, lu->lun);
 902                         /* Let any waiting I/O fail from now on. */
 903                         sbp2_unblock(lu->tgt);
 904                 }
 905                 goto out;
 906         }
 907
 908         tgt->node_id      = node_id;
 909         tgt->address_high = local_node_id << 16;
 910         smp_wmb();        /* node IDs must not be older than generation */
 911         lu->generation    = generation;
 912
 913         lu->command_block_agent_address =
 914                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 915                       << 32) | be32_to_cpu(response.command_block_agent.low);
 916         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 917
 918         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
 919                   tgt->bus_id, lu->lun, lu->retries);
 920
 921         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 922         sbp2_set_busy_timeout(lu);
 923
 924         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
 925         sbp2_agent_reset(lu);
 926
 927         /* This was a re-login. */
 928         if (lu->has_sdev) {
 929                 sbp2_cancel_orbs(lu);
 930                 sbp2_conditionally_unblock(lu);
 931                 goto out;
 932         }
 933
 934         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 935                 ssleep(SBP2_INQUIRY_DELAY);
 936
 937         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 938         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 939         /*
 940          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 941          * Therefore __scsi_add_device() will get into trouble if a bus reset
 942          * happens in parallel.  It will either fail or leave us with an
 943          * unusable sdev.  As a workaround we check for this and retry the
 944          * whole login and SCSI probing.
 945          */
 946
 947         /* Reported error during __scsi_add_device() */
 948         if (IS_ERR(sdev))
 949                 goto out_logout_login;
 950
 951         /* Unreported error during __scsi_add_device() */
 952         smp_rmb(); /* get current card generation */
 953         if (generation != device->card->generation) {
 954                 scsi_remove_device(sdev);
 955                 scsi_device_put(sdev);
 956                 goto out_logout_login;
 957         }
 958
 959         /* No error during __scsi_add_device() */
 960         lu->has_sdev = true;
 961         scsi_device_put(sdev);
 962         sbp2_allow_block(lu);
 963         goto out;
 964
 965  out_logout_login:
 966         smp_rmb(); /* generation may have changed */
 967         generation = device->generation;
 968         smp_rmb(); /* node_id must not be older than generation */
 969
 970         sbp2_send_management_orb(lu, device->node_id, generation,
 971                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 972         /*
 973          * If a bus reset happened, sbp2_update will have requeued
 974          * lu->work already.  Reset the work from reconnect to login.
 975          */
 976         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
 977  out:
 978         sbp2_target_put(tgt);
 979 }
 980
 981 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 982 {
 983         struct sbp2_logical_unit *lu;
 984
 985         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 986         if (!lu)
 987                 return -ENOMEM;
 988
 989         lu->address_handler.length           = 0x100;
 990         lu->address_handler.address_callback = sbp2_status_write;
 991         lu->address_handler.callback_data    = lu;
 992
 993         if (fw_core_add_address_handler(&lu->address_handler,
 994                                         &fw_high_memory_region) < 0) {
 995                 kfree(lu);
 996                 return -ENOMEM;
 997         }
 998
 999         lu->tgt      = tgt;
1000         lu->lun      = lun_entry & 0xffff;
1001         lu->login_id = INVALID_LOGIN_ID;
1002         lu->retries  = 0;
1003         lu->has_sdev = false;
1004         lu->blocked  = false;
1005         ++tgt->dont_block;
1006         INIT_LIST_HEAD(&lu->orb_list);
1007         INIT_DELAYED_WORK(&lu->work, sbp2_login);
1008
1009         list_add_tail(&lu->link, &tgt->lu_list);
1010         return 0;
1011 }
1012
1013 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
1014 {
1015         struct fw_csr_iterator ci;
1016         int key, value;
1017
1018         fw_csr_iterator_init(&ci, directory);
1019         while (fw_csr_iterator_next(&ci, &key, &value))
1020                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1021                     sbp2_add_logical_unit(tgt, value) < 0)
1022                         return -ENOMEM;
1023         return 0;
1024 }
1025
1026 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
1027                               u32 *model, u32 *firmware_revision)
1028 {
1029         struct fw_csr_iterator ci;
1030         int key, value;
1031         unsigned int timeout;
1032
1033         fw_csr_iterator_init(&ci, directory);
1034         while (fw_csr_iterator_next(&ci, &key, &value)) {
1035                 switch (key) {
1036
1037                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1038                         tgt->management_agent_address =
1039                                         CSR_REGISTER_BASE + 4 * value;
1040                         break;
1041
1042                 case CSR_DIRECTORY_ID:
1043                         tgt->directory_id = value;
1044                         break;
1045
1046                 case CSR_MODEL:
1047                         *model = value;
1048                         break;
1049
1050                 case SBP2_CSR_FIRMWARE_REVISION:
1051                         *firmware_revision = value;
1052                         break;
1053
1054                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1055                         /* the timeout value is stored in 500ms units */
1056                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1057                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1058                         tgt->mgt_orb_timeout =
1059                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1060
1061                         if (timeout > tgt->mgt_orb_timeout)
1062                                 fw_notify("%s: config rom contains %ds "
1063                                           "management ORB timeout, limiting "
1064                                           "to %ds\n", tgt->bus_id,
1065                                           timeout / 1000,
1066                                           tgt->mgt_orb_timeout / 1000);
1067                         break;
1068
1069                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1070                         if (sbp2_add_logical_unit(tgt, value) < 0)
1071                                 return -ENOMEM;
1072                         break;
1073
1074                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1075                         /* Adjust for the increment in the iterator */
1076                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1077                                 return -ENOMEM;
1078                         break;
1079                 }
1080         }
1081         return 0;
1082 }
1083
1084 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1085                                   u32 firmware_revision)
1086 {
1087         int i;
1088         unsigned int w = sbp2_param_workarounds;
1089
1090         if (w)
1091                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1092                           "if you need the workarounds parameter for %s\n",
1093                           tgt->bus_id);
1094
1095         if (w & SBP2_WORKAROUND_OVERRIDE)
1096                 goto out;
1097
1098         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1099
1100                 if (sbp2_workarounds_table[i].firmware_revision !=
1101                     (firmware_revision & 0xffffff00))
1102                         continue;
1103
1104                 if (sbp2_workarounds_table[i].model != model &&
1105                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1106                         continue;
1107
1108                 w |= sbp2_workarounds_table[i].workarounds;
1109                 break;
1110         }
1111  out:
1112         if (w)
1113                 fw_notify("Workarounds for %s: 0x%x "
1114                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1115                           tgt->bus_id, w, firmware_revision, model);
1116         tgt->workarounds = w;
1117 }
1118
1119 static struct scsi_host_template scsi_driver_template;
1120
1121 static int sbp2_probe(struct device *dev)
1122 {
1123         struct fw_unit *unit = fw_unit(dev);
1124         struct fw_device *device = fw_parent_device(unit);
1125         struct sbp2_target *tgt;
1126         struct sbp2_logical_unit *lu;
1127         struct Scsi_Host *shost;
1128         u32 model, firmware_revision;
1129
1130         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1131                 BUG_ON(dma_set_max_seg_size(device->card->device,
1132                                             SBP2_MAX_SEG_SIZE));
1133
1134         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1135         if (shost == NULL)
1136                 return -ENOMEM;
1137
1138         tgt = (struct sbp2_target *)shost->hostdata;
1139         dev_set_drvdata(&unit->device, tgt);
1140         tgt->unit = unit;
1141         kref_init(&tgt->kref);
1142         INIT_LIST_HEAD(&tgt->lu_list);
1143         tgt->bus_id = dev_name(&unit->device);
1144         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1145
1146         if (fw_device_enable_phys_dma(device) < 0)
1147                 goto fail_shost_put;
1148
1149         if (scsi_add_host(shost, &unit->device) < 0)
1150                 goto fail_shost_put;
1151
1152         fw_device_get(device);
1153         fw_unit_get(unit);
1154
1155         /* implicit directory ID */
1156         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1157                              + CSR_CONFIG_ROM) & 0xffffff;
1158
1159         firmware_revision = SBP2_ROM_VALUE_MISSING;
1160         model             = SBP2_ROM_VALUE_MISSING;
1161
1162         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1163                                &firmware_revision) < 0)
1164                 goto fail_tgt_put;
1165
1166         sbp2_init_workarounds(tgt, model, firmware_revision);
1167
1168         /*
1169          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1170          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1171          * specifies the max payload size as 2 ^ (max_payload + 2), so
1172          * if we set this to max_speed + 7, we get the right value.
1173          */
1174         tgt->max_payload = min(device->max_speed + 7, 10U);
1175         tgt->max_payload = min(tgt->max_payload, device->card->max_receive - 1);
1176
1177         /* Do the login in a workqueue so we can easily reschedule retries. */
1178         list_for_each_entry(lu, &tgt->lu_list, link)
1179                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1180         return 0;
1181
1182  fail_tgt_put:
1183         sbp2_target_put(tgt);
1184         return -ENOMEM;
1185
1186  fail_shost_put:
1187         scsi_host_put(shost);
1188         return -ENOMEM;
1189 }
1190
1191 static int sbp2_remove(struct device *dev)
1192 {
1193         struct fw_unit *unit = fw_unit(dev);
1194         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1195
1196         sbp2_target_put(tgt);
1197         return 0;
1198 }
1199
1200 static void sbp2_reconnect(struct work_struct *work)
1201 {
1202         struct sbp2_logical_unit *lu =
1203                 container_of(work, struct sbp2_logical_unit, work.work);
1204         struct sbp2_target *tgt = lu->tgt;
1205         struct fw_device *device = target_device(tgt);
1206         int generation, node_id, local_node_id;
1207
1208         if (fw_device_is_shutdown(device))
1209                 goto out;
1210
1211         generation    = device->generation;
1212         smp_rmb();    /* node IDs must not be older than generation */
1213         node_id       = device->node_id;
1214         local_node_id = device->card->node_id;
1215
1216         if (sbp2_send_management_orb(lu, node_id, generation,
1217                                      SBP2_RECONNECT_REQUEST,
1218                                      lu->login_id, NULL) < 0) {
1219                 /*
1220                  * If reconnect was impossible even though we are in the
1221                  * current generation, fall back and try to log in again.
1222                  *
1223                  * We could check for "Function rejected" status, but
1224                  * looking at the bus generation as simpler and more general.
1225                  */
1226                 smp_rmb(); /* get current card generation */
1227                 if (generation == device->card->generation ||
1228                     lu->retries++ >= 5) {
1229                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1230                         lu->retries = 0;
1231                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1232                 }
1233                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1234                 goto out;
1235         }
1236
1237         tgt->node_id      = node_id;
1238         tgt->address_high = local_node_id << 16;
1239         smp_wmb();        /* node IDs must not be older than generation */
1240         lu->generation    = generation;
1241
1242         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1243                   tgt->bus_id, lu->lun, lu->retries);
1244
1245         sbp2_agent_reset(lu);
1246         sbp2_cancel_orbs(lu);
1247         sbp2_conditionally_unblock(lu);
1248  out:
1249         sbp2_target_put(tgt);
1250 }
1251
1252 static void sbp2_update(struct fw_unit *unit)
1253 {
1254         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1255         struct sbp2_logical_unit *lu;
1256
1257         fw_device_enable_phys_dma(fw_parent_device(unit));
1258
1259         /*
1260          * Fw-core serializes sbp2_update() against sbp2_remove().
1261          * Iteration over tgt->lu_list is therefore safe here.
1262          */
1263         list_for_each_entry(lu, &tgt->lu_list, link) {
1264                 sbp2_conditionally_block(lu);
1265                 lu->retries = 0;
1266                 sbp2_queue_work(lu, 0);
1267         }
1268 }
1269
1270 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1271 #define SBP2_SW_VERSION_ENTRY   0x00010483
1272
1273 static const struct ieee1394_device_id sbp2_id_table[] = {
1274         {
1275                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1276                                 IEEE1394_MATCH_VERSION,
1277                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1278                 .version      = SBP2_SW_VERSION_ENTRY,
1279         },
1280         { }
1281 };
1282
1283 static struct fw_driver sbp2_driver = {
1284         .driver   = {
1285                 .owner  = THIS_MODULE,
1286                 .name   = sbp2_driver_name,
1287                 .bus    = &fw_bus_type,
1288                 .probe  = sbp2_probe,
1289                 .remove = sbp2_remove,
1290         },
1291         .update   = sbp2_update,
1292         .id_table = sbp2_id_table,
1293 };
1294
1295 static void sbp2_unmap_scatterlist(struct device *card_device,
1296                                    struct sbp2_command_orb *orb)
1297 {
1298         if (scsi_sg_count(orb->cmd))
1299                 dma_unmap_sg(card_device, scsi_sglist(orb->cmd),
1300                              scsi_sg_count(orb->cmd),
1301                              orb->cmd->sc_data_direction);
1302
1303         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1304                 dma_unmap_single(card_device, orb->page_table_bus,
1305                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1306 }
1307
1308 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1309 {
1310         int sam_status;
1311
1312         sense_data[0] = 0x70;
1313         sense_data[1] = 0x0;
1314         sense_data[2] = sbp2_status[1];
1315         sense_data[3] = sbp2_status[4];
1316         sense_data[4] = sbp2_status[5];
1317         sense_data[5] = sbp2_status[6];
1318         sense_data[6] = sbp2_status[7];
1319         sense_data[7] = 10;
1320         sense_data[8] = sbp2_status[8];
1321         sense_data[9] = sbp2_status[9];
1322         sense_data[10] = sbp2_status[10];
1323         sense_data[11] = sbp2_status[11];
1324         sense_data[12] = sbp2_status[2];
1325         sense_data[13] = sbp2_status[3];
1326         sense_data[14] = sbp2_status[12];
1327         sense_data[15] = sbp2_status[13];
1328
1329         sam_status = sbp2_status[0] & 0x3f;
1330
1331         switch (sam_status) {
1332         case SAM_STAT_GOOD:
1333         case SAM_STAT_CHECK_CONDITION:
1334         case SAM_STAT_CONDITION_MET:
1335         case SAM_STAT_BUSY:
1336         case SAM_STAT_RESERVATION_CONFLICT:
1337         case SAM_STAT_COMMAND_TERMINATED:
1338                 return DID_OK << 16 | sam_status;
1339
1340         default:
1341                 return DID_ERROR << 16;
1342         }
1343 }
1344
1345 static void complete_command_orb(struct sbp2_orb *base_orb,
1346                                  struct sbp2_status *status)
1347 {
1348         struct sbp2_command_orb *orb =
1349                 container_of(base_orb, struct sbp2_command_orb, base);
1350         struct fw_device *device = target_device(orb->lu->tgt);
1351         int result;
1352
1353         if (status != NULL) {
1354                 if (STATUS_GET_DEAD(*status))
1355                         sbp2_agent_reset_no_wait(orb->lu);
1356
1357                 switch (STATUS_GET_RESPONSE(*status)) {
1358                 case SBP2_STATUS_REQUEST_COMPLETE:
1359                         result = DID_OK << 16;
1360                         break;
1361                 case SBP2_STATUS_TRANSPORT_FAILURE:
1362                         result = DID_BUS_BUSY << 16;
1363                         break;
1364                 case SBP2_STATUS_ILLEGAL_REQUEST:
1365                 case SBP2_STATUS_VENDOR_DEPENDENT:
1366                 default:
1367                         result = DID_ERROR << 16;
1368                         break;
1369                 }
1370
1371                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1372                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1373                                                            orb->cmd->sense_buffer);
1374         } else {
1375                 /*
1376                  * If the orb completes with status == NULL, something
1377                  * went wrong, typically a bus reset happened mid-orb
1378                  * or when sending the write (less likely).
1379                  */
1380                 result = DID_BUS_BUSY << 16;
1381                 sbp2_conditionally_block(orb->lu);
1382         }
1383
1384         dma_unmap_single(device->card->device, orb->base.request_bus,
1385                          sizeof(orb->request), DMA_TO_DEVICE);
1386         sbp2_unmap_scatterlist(device->card->device, orb);
1387
1388         orb->cmd->result = result;
1389         orb->done(orb->cmd);
1390 }
1391
1392 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1393                 struct fw_device *device, struct sbp2_logical_unit *lu)
1394 {
1395         struct scatterlist *sg = scsi_sglist(orb->cmd);
1396         int i, n;
1397
1398         n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1399                        orb->cmd->sc_data_direction);
1400         if (n == 0)
1401                 goto fail;
1402
1403         /*
1404          * Handle the special case where there is only one element in
1405          * the scatter list by converting it to an immediate block
1406          * request. This is also a workaround for broken devices such
1407          * as the second generation iPod which doesn't support page
1408          * tables.
1409          */
1410         if (n == 1) {
1411                 orb->request.data_descriptor.high =
1412                         cpu_to_be32(lu->tgt->address_high);
1413                 orb->request.data_descriptor.low  =
1414                         cpu_to_be32(sg_dma_address(sg));
1415                 orb->request.misc |=
1416                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1417                 return 0;
1418         }
1419
1420         for_each_sg(sg, sg, n, i) {
1421                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1422                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1423         }
1424
1425         orb->page_table_bus =
1426                 dma_map_single(device->card->device, orb->page_table,
1427                                sizeof(orb->page_table), DMA_TO_DEVICE);
1428         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1429                 goto fail_page_table;
1430
1431         /*
1432          * The data_descriptor pointer is the one case where we need
1433          * to fill in the node ID part of the address.  All other
1434          * pointers assume that the data referenced reside on the
1435          * initiator (i.e. us), but data_descriptor can refer to data
1436          * on other nodes so we need to put our ID in descriptor.high.
1437          */
1438         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1439         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1440         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1441                                          COMMAND_ORB_DATA_SIZE(n));
1442
1443         return 0;
1444
1445  fail_page_table:
1446         dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1447                      scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
1448  fail:
1449         return -ENOMEM;
1450 }
1451
1452 /* SCSI stack integration */
1453
1454 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1455 {
1456         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1457         struct fw_device *device = target_device(lu->tgt);
1458         struct sbp2_command_orb *orb;
1459         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1460
1461         /*
1462          * Bidirectional commands are not yet implemented, and unknown
1463          * transfer direction not handled.
1464          */
1465         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1466                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1467                 cmd->result = DID_ERROR << 16;
1468                 done(cmd);
1469                 return 0;
1470         }
1471
1472         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1473         if (orb == NULL) {
1474                 fw_notify("failed to alloc orb\n");
1475                 return SCSI_MLQUEUE_HOST_BUSY;
1476         }
1477
1478         /* Initialize rcode to something not RCODE_COMPLETE. */
1479         orb->base.rcode = -1;
1480         kref_init(&orb->base.kref);
1481
1482         orb->lu   = lu;
1483         orb->done = done;
1484         orb->cmd  = cmd;
1485
1486         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1487         orb->request.misc = cpu_to_be32(
1488                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1489                 COMMAND_ORB_SPEED(device->max_speed) |
1490                 COMMAND_ORB_NOTIFY);
1491
1492         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1493                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1494
1495         generation = device->generation;
1496         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1497
1498         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1499                 goto out;
1500
1501         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1502
1503         orb->base.callback = complete_command_orb;
1504         orb->base.request_bus =
1505                 dma_map_single(device->card->device, &orb->request,
1506                                sizeof(orb->request), DMA_TO_DEVICE);
1507         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1508                 sbp2_unmap_scatterlist(device->card->device, orb);
1509                 goto out;
1510         }
1511
1512         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1513                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1514         retval = 0;
1515  out:
1516         kref_put(&orb->base.kref, free_orb);
1517         return retval;
1518 }
1519
1520 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1521 {
1522         struct sbp2_logical_unit *lu = sdev->hostdata;
1523
1524         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1525         if (!lu)
1526                 return -ENOSYS;
1527
1528         sdev->allow_restart = 1;
1529
1530         /* SBP-2 requires quadlet alignment of the data buffers. */
1531         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1532
1533         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1534                 sdev->inquiry_len = 36;
1535
1536         return 0;
1537 }
1538
1539 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1540 {
1541         struct sbp2_logical_unit *lu = sdev->hostdata;
1542
1543         sdev->use_10_for_rw = 1;
1544
1545         if (sbp2_param_exclusive_login)
1546                 sdev->manage_start_stop = 1;
1547
1548         if (sdev->type == TYPE_ROM)
1549                 sdev->use_10_for_ms = 1;
1550
1551         if (sdev->type == TYPE_DISK &&
1552             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1553                 sdev->skip_ms_page_8 = 1;
1554
1555         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1556                 sdev->fix_capacity = 1;
1557
1558         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1559                 sdev->start_stop_pwr_cond = 1;
1560
1561         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1562                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1563
1564         blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
1565
1566         return 0;
1567 }
1568
1569 /*
1570  * Called by scsi stack when something has really gone wrong.  Usually
1571  * called when a command has timed-out for some reason.
1572  */
1573 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1574 {
1575         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1576
1577         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1578         sbp2_agent_reset(lu);
1579         sbp2_cancel_orbs(lu);
1580
1581         return SUCCESS;
1582 }
1583
1584 /*
1585  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1586  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1587  *
1588  * This is the concatenation of target port identifier and logical unit
1589  * identifier as per SAM-2...SAM-4 annex A.
1590  */
1591 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1592                         struct device_attribute *attr, char *buf)
1593 {
1594         struct scsi_device *sdev = to_scsi_device(dev);
1595         struct sbp2_logical_unit *lu;
1596
1597         if (!sdev)
1598                 return 0;
1599
1600         lu = sdev->hostdata;
1601
1602         return sprintf(buf, "%016llx:%06x:%04x\n",
1603                         (unsigned long long)lu->tgt->guid,
1604                         lu->tgt->directory_id, lu->lun);
1605 }
1606
1607 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1608
1609 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1610         &dev_attr_ieee1394_id,
1611         NULL
1612 };
1613
1614 static struct scsi_host_template scsi_driver_template = {
1615         .module                 = THIS_MODULE,
1616         .name                   = "SBP-2 IEEE-1394",
1617         .proc_name              = sbp2_driver_name,
1618         .queuecommand           = sbp2_scsi_queuecommand,
1619         .slave_alloc            = sbp2_scsi_slave_alloc,
1620         .slave_configure        = sbp2_scsi_slave_configure,
1621         .eh_abort_handler       = sbp2_scsi_abort,
1622         .this_id                = -1,
1623         .sg_tablesize           = SG_ALL,
1624         .use_clustering         = ENABLE_CLUSTERING,
1625         .cmd_per_lun            = 1,
1626         .can_queue              = 1,
1627         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1628 };
1629
1630 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1631 MODULE_DESCRIPTION("SCSI over IEEE1394");
1632 MODULE_LICENSE("GPL");
1633 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1634
1635 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1636 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1637 MODULE_ALIAS("sbp2");
1638 #endif
1639
1640 static int __init sbp2_init(void)
1641 {
1642         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1643         if (!sbp2_wq)
1644                 return -ENOMEM;
1645
1646         return driver_register(&sbp2_driver.driver);
1647 }
1648
1649 static void __exit sbp2_cleanup(void)
1650 {
1651         driver_unregister(&sbp2_driver.driver);
1652         destroy_workqueue(sbp2_wq);
1653 }
1654
1655 module_init(sbp2_init);
1656 module_exit(sbp2_cleanup);