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
  56 #include <scsi/scsi.h>
  57 #include <scsi/scsi_cmnd.h>
  58 #include <scsi/scsi_device.h>
  59 #include <scsi/scsi_host.h>
  60
  61 /*
  62  * So far only bridges from Oxford Semiconductor are known to support
  63  * concurrent logins. Depending on firmware, four or two concurrent logins
  64  * are possible on OXFW911 and newer Oxsemi bridges.
  65  *
  66  * Concurrent logins are useful together with cluster filesystems.
  67  */
  68 static bool sbp2_param_exclusive_login = 1;
  69 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  70 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  71                  "(default = Y, use N for concurrent initiators)");
  72
  73 /*
  74  * Flags for firmware oddities
  75  *
  76  * - 128kB max transfer
  77  *   Limit transfer size. Necessary for some old bridges.
  78  *
  79  * - 36 byte inquiry
  80  *   When scsi_mod probes the device, let the inquiry command look like that
  81  *   from MS Windows.
  82  *
  83  * - skip mode page 8
  84  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  85  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  86  *
  87  * - fix capacity
  88  *   Tell sd_mod to correct the last sector number reported by read_capacity.
  89  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  90  *   Don't use this with devices which don't have this bug.
  91  *
  92  * - delay inquiry
  93  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  94  *
  95  * - power condition
  96  *   Set the power condition field in the START STOP UNIT commands sent by
  97  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  98  *   Some disks need this to spin down or to resume properly.
  99  *
 100  * - override internal blacklist
 101  *   Instead of adding to the built-in blacklist, use only the workarounds
 102  *   specified in the module load parameter.
 103  *   Useful if a blacklist entry interfered with a non-broken device.
 104  */
 105 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
 106 #define SBP2_WORKAROUND_INQUIRY_36      0x2
 107 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
 108 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
 109 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
 110 #define SBP2_INQUIRY_DELAY              12
 111 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
 112 #define SBP2_WORKAROUND_OVERRIDE        0x100
 113
 114 static int sbp2_param_workarounds;
 115 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 116 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 117         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 118         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 119         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 120         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 121         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 122         ", set power condition in start stop unit = "
 123                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 124         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 125         ", or a combination)");
 126
 127 /*
 128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 129  * and one struct scsi_device per sbp2_logical_unit.
 130  */
 131 struct sbp2_logical_unit {
 132         struct sbp2_target *tgt;
 133         struct list_head link;
 134         struct fw_address_handler address_handler;
 135         struct list_head orb_list;
 136
 137         u64 command_block_agent_address;
 138         u16 lun;
 139         int login_id;
 140
 141         /*
 142          * The generation is updated once we've logged in or reconnected
 143          * to the logical unit.  Thus, I/O to the device will automatically
 144          * fail and get retried if it happens in a window where the device
 145          * is not ready, e.g. after a bus reset but before we reconnect.
 146          */
 147         int generation;
 148         int retries;
 149         work_func_t workfn;
 150         struct delayed_work work;
 151         bool has_sdev;
 152         bool blocked;
 153 };
 154
 155 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 156 {
 157         queue_delayed_work(fw_workqueue, &lu->work, delay);
 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 fw_unit *unit;
 166         struct list_head lu_list;
 167
 168         u64 management_agent_address;
 169         u64 guid;
 170         int directory_id;
 171         int node_id;
 172         int address_high;
 173         unsigned int workarounds;
 174         unsigned int mgt_orb_timeout;
 175         unsigned int max_payload;
 176
 177         spinlock_t lock;
 178         int dont_block; /* counter for each logical unit */
 179         int blocked;    /* ditto */
 180 };
 181
 182 static struct fw_device *target_parent_device(struct sbp2_target *tgt)
 183 {
 184         return fw_parent_device(tgt->unit);
 185 }
 186
 187 static const struct device *tgt_dev(const struct sbp2_target *tgt)
 188 {
 189         return &tgt->unit->device;
 190 }
 191
 192 static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
 193 {
 194         return &lu->tgt->unit->device;
 195 }
 196
 197 /* Impossible login_id, to detect logout attempt before successful login */
 198 #define INVALID_LOGIN_ID 0x10000
 199
 200 #define SBP2_ORB_TIMEOUT                2000U           /* Timeout in ms */
 201 #define SBP2_ORB_NULL                   0x80000000
 202 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 203 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 204
 205 /*
 206  * There is no transport protocol limit to the CDB length,  but we implement
 207  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
 208  */
 209 #define SBP2_MAX_CDB_SIZE               16
 210
 211 /*
 212  * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
 213  * for compatibility with earlier versions of this driver.
 214  */
 215 #define SBP2_MAX_SEG_SIZE               0xfffc
 216
 217 /* Unit directory keys */
 218 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 219 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 220 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 221 #define SBP2_CSR_UNIT_UNIQUE_ID         0x8d
 222 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 223
 224 /* Management orb opcodes */
 225 #define SBP2_LOGIN_REQUEST              0x0
 226 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 227 #define SBP2_RECONNECT_REQUEST          0x3
 228 #define SBP2_SET_PASSWORD_REQUEST       0x4
 229 #define SBP2_LOGOUT_REQUEST             0x7
 230 #define SBP2_ABORT_TASK_REQUEST         0xb
 231 #define SBP2_ABORT_TASK_SET             0xc
 232 #define SBP2_LOGICAL_UNIT_RESET         0xe
 233 #define SBP2_TARGET_RESET_REQUEST       0xf
 234
 235 /* Offsets for command block agent registers */
 236 #define SBP2_AGENT_STATE                0x00
 237 #define SBP2_AGENT_RESET                0x04
 238 #define SBP2_ORB_POINTER                0x08
 239 #define SBP2_DOORBELL                   0x10
 240 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 241
 242 /* Status write response codes */
 243 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 244 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 245 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 246 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 247
 248 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 249 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 250 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 251 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 252 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 253 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 254 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 255 #define STATUS_GET_DATA(v)              ((v).data)
 256
 257 struct sbp2_status {
 258         u32 status;
 259         u32 orb_low;
 260         u8 data[24];
 261 };
 262
 263 struct sbp2_pointer {
 264         __be32 high;
 265         __be32 low;
 266 };
 267
 268 struct sbp2_orb {
 269         struct fw_transaction t;
 270         struct kref kref;
 271         dma_addr_t request_bus;
 272         int rcode;
 273         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 274         struct sbp2_logical_unit *lu;
 275         struct list_head link;
 276 };
 277
 278 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 279 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 280 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 281 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 282 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 283 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 284
 285 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 286 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 287
 288 struct sbp2_management_orb {
 289         struct sbp2_orb base;
 290         struct {
 291                 struct sbp2_pointer password;
 292                 struct sbp2_pointer response;
 293                 __be32 misc;
 294                 __be32 length;
 295                 struct sbp2_pointer status_fifo;
 296         } request;
 297         __be32 response[4];
 298         dma_addr_t response_bus;
 299         struct completion done;
 300         struct sbp2_status status;
 301 };
 302
 303 struct sbp2_login_response {
 304         __be32 misc;
 305         struct sbp2_pointer command_block_agent;
 306         __be32 reconnect_hold;
 307 };
 308 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 309 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 310 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 311 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 312 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 313 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 314 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 315 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 316
 317 struct sbp2_command_orb {
 318         struct sbp2_orb base;
 319         struct {
 320                 struct sbp2_pointer next;
 321                 struct sbp2_pointer data_descriptor;
 322                 __be32 misc;
 323                 u8 command_block[SBP2_MAX_CDB_SIZE];
 324         } request;
 325         struct scsi_cmnd *cmd;
 326
 327         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 328         dma_addr_t page_table_bus;
 329 };
 330
 331 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 332 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 333
 334 /*
 335  * List of devices with known bugs.
 336  *
 337  * The firmware_revision field, masked with 0xffff00, is the best
 338  * indicator for the type of bridge chip of a device.  It yields a few
 339  * false positives but this did not break correctly behaving devices
 340  * so far.
 341  */
 342 static const struct {
 343         u32 firmware_revision;
 344         u32 model;
 345         unsigned int workarounds;
 346 } sbp2_workarounds_table[] = {
 347         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 348                 .firmware_revision      = 0x002800,
 349                 .model                  = 0x001010,
 350                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 351                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 352                                           SBP2_WORKAROUND_POWER_CONDITION,
 353         },
 354         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 355                 .firmware_revision      = 0x002800,
 356                 .model                  = 0x000000,
 357                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 358         },
 359         /* Initio bridges, actually only needed for some older ones */ {
 360                 .firmware_revision      = 0x000200,
 361                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 362                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 363         },
 364         /* PL-3507 bridge with Prolific firmware */ {
 365                 .firmware_revision      = 0x012800,
 366                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 367                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 368         },
 369         /* Symbios bridge */ {
 370                 .firmware_revision      = 0xa0b800,
 371                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 372                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 373         },
 374         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 375                 .firmware_revision      = 0x002600,
 376                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 377                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 378         },
 379         /*
 380          * iPod 2nd generation: needs 128k max transfer size workaround
 381          * iPod 3rd generation: needs fix capacity workaround
 382          */
 383         {
 384                 .firmware_revision      = 0x0a2700,
 385                 .model                  = 0x000000,
 386                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 387                                           SBP2_WORKAROUND_FIX_CAPACITY,
 388         },
 389         /* iPod 4th generation */ {
 390                 .firmware_revision      = 0x0a2700,
 391                 .model                  = 0x000021,
 392                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 393         },
 394         /* iPod mini */ {
 395                 .firmware_revision      = 0x0a2700,
 396                 .model                  = 0x000022,
 397                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 398         },
 399         /* iPod mini */ {
 400                 .firmware_revision      = 0x0a2700,
 401                 .model                  = 0x000023,
 402                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 403         },
 404         /* iPod Photo */ {
 405                 .firmware_revision      = 0x0a2700,
 406                 .model                  = 0x00007e,
 407                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 408         }
 409 };
 410
 411 static void free_orb(struct kref *kref)
 412 {
 413         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 414
 415         kfree(orb);
 416 }
 417
 418 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 419                               int tcode, int destination, int source,
 420                               int generation, unsigned long long offset,
 421                               void *payload, size_t length, void *callback_data)
 422 {
 423         struct sbp2_logical_unit *lu = callback_data;
 424         struct sbp2_orb *orb;
 425         struct sbp2_status status;
 426         unsigned long flags;
 427
 428         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 429             length < 8 || length > sizeof(status)) {
 430                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 431                 return;
 432         }
 433
 434         status.status  = be32_to_cpup(payload);
 435         status.orb_low = be32_to_cpup(payload + 4);
 436         memset(status.data, 0, sizeof(status.data));
 437         if (length > 8)
 438                 memcpy(status.data, payload + 8, length - 8);
 439
 440         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 441                 dev_notice(lu_dev(lu),
 442                            "non-ORB related status write, not handled\n");
 443                 fw_send_response(card, request, RCODE_COMPLETE);
 444                 return;
 445         }
 446
 447         /* Lookup the orb corresponding to this status write. */
 448         spin_lock_irqsave(&lu->tgt->lock, flags);
 449         list_for_each_entry(orb, &lu->orb_list, link) {
 450                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 451                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 452                         orb->rcode = RCODE_COMPLETE;
 453                         list_del(&orb->link);
 454                         break;
 455                 }
 456         }
 457         spin_unlock_irqrestore(&lu->tgt->lock, flags);
 458
 459         if (&orb->link != &lu->orb_list) {
 460                 orb->callback(orb, &status);
 461                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 462         } else {
 463                 dev_err(lu_dev(lu), "status write for unknown ORB\n");
 464         }
 465
 466         fw_send_response(card, request, RCODE_COMPLETE);
 467 }
 468
 469 static void complete_transaction(struct fw_card *card, int rcode,
 470                                  void *payload, size_t length, void *data)
 471 {
 472         struct sbp2_orb *orb = data;
 473         unsigned long flags;
 474
 475         /*
 476          * This is a little tricky.  We can get the status write for
 477          * the orb before we get this callback.  The status write
 478          * handler above will assume the orb pointer transaction was
 479          * successful and set the rcode to RCODE_COMPLETE for the orb.
 480          * So this callback only sets the rcode if it hasn't already
 481          * been set and only does the cleanup if the transaction
 482          * failed and we didn't already get a status write.
 483          */
 484         spin_lock_irqsave(&orb->lu->tgt->lock, flags);
 485
 486         if (orb->rcode == -1)
 487                 orb->rcode = rcode;
 488         if (orb->rcode != RCODE_COMPLETE) {
 489                 list_del(&orb->link);
 490                 spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 491
 492                 orb->callback(orb, NULL);
 493                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 494         } else {
 495                 spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 496         }
 497
 498         kref_put(&orb->kref, free_orb); /* transaction callback reference */
 499 }
 500
 501 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 502                           int node_id, int generation, u64 offset)
 503 {
 504         struct fw_device *device = target_parent_device(lu->tgt);
 505         struct sbp2_pointer orb_pointer;
 506         unsigned long flags;
 507
 508         orb_pointer.high = 0;
 509         orb_pointer.low = cpu_to_be32(orb->request_bus);
 510
 511         orb->lu = lu;
 512         spin_lock_irqsave(&lu->tgt->lock, flags);
 513         list_add_tail(&orb->link, &lu->orb_list);
 514         spin_unlock_irqrestore(&lu->tgt->lock, flags);
 515
 516         kref_get(&orb->kref); /* transaction callback reference */
 517         kref_get(&orb->kref); /* orb callback reference */
 518
 519         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 520                         node_id, generation, device->max_speed, offset,
 521                         &orb_pointer, 8, complete_transaction, orb);
 522 }
 523
 524 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 525 {
 526         struct fw_device *device = target_parent_device(lu->tgt);
 527         struct sbp2_orb *orb, *next;
 528         struct list_head list;
 529         int retval = -ENOENT;
 530
 531         INIT_LIST_HEAD(&list);
 532         spin_lock_irq(&lu->tgt->lock);
 533         list_splice_init(&lu->orb_list, &list);
 534         spin_unlock_irq(&lu->tgt->lock);
 535
 536         list_for_each_entry_safe(orb, next, &list, link) {
 537                 retval = 0;
 538                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 539                         continue;
 540
 541                 orb->rcode = RCODE_CANCELLED;
 542                 orb->callback(orb, NULL);
 543                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 544         }
 545
 546         return retval;
 547 }
 548
 549 static void complete_management_orb(struct sbp2_orb *base_orb,
 550                                     struct sbp2_status *status)
 551 {
 552         struct sbp2_management_orb *orb =
 553                 container_of(base_orb, struct sbp2_management_orb, base);
 554
 555         if (status)
 556                 memcpy(&orb->status, status, sizeof(*status));
 557         complete(&orb->done);
 558 }
 559
 560 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 561                                     int generation, int function,
 562                                     int lun_or_login_id, void *response)
 563 {
 564         struct fw_device *device = target_parent_device(lu->tgt);
 565         struct sbp2_management_orb *orb;
 566         unsigned int timeout;
 567         int retval = -ENOMEM;
 568
 569         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 570                 return 0;
 571
 572         orb = kzalloc(sizeof(*orb), GFP_NOIO);
 573         if (orb == NULL)
 574                 return -ENOMEM;
 575
 576         kref_init(&orb->base.kref);
 577         orb->response_bus =
 578                 dma_map_single(device->card->device, &orb->response,
 579                                sizeof(orb->response), DMA_FROM_DEVICE);
 580         if (dma_mapping_error(device->card->device, orb->response_bus))
 581                 goto fail_mapping_response;
 582
 583         orb->request.response.high = 0;
 584         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 585
 586         orb->request.misc = cpu_to_be32(
 587                 MANAGEMENT_ORB_NOTIFY |
 588                 MANAGEMENT_ORB_FUNCTION(function) |
 589                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 590         orb->request.length = cpu_to_be32(
 591                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 592
 593         orb->request.status_fifo.high =
 594                 cpu_to_be32(lu->address_handler.offset >> 32);
 595         orb->request.status_fifo.low  =
 596                 cpu_to_be32(lu->address_handler.offset);
 597
 598         if (function == SBP2_LOGIN_REQUEST) {
 599                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 600                 orb->request.misc |= cpu_to_be32(
 601                         MANAGEMENT_ORB_RECONNECT(2) |
 602                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 603                 timeout = lu->tgt->mgt_orb_timeout;
 604         } else {
 605                 timeout = SBP2_ORB_TIMEOUT;
 606         }
 607
 608         init_completion(&orb->done);
 609         orb->base.callback = complete_management_orb;
 610
 611         orb->base.request_bus =
 612                 dma_map_single(device->card->device, &orb->request,
 613                                sizeof(orb->request), DMA_TO_DEVICE);
 614         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 615                 goto fail_mapping_request;
 616
 617         sbp2_send_orb(&orb->base, lu, node_id, generation,
 618                       lu->tgt->management_agent_address);
 619
 620         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 621
 622         retval = -EIO;
 623         if (sbp2_cancel_orbs(lu) == 0) {
 624                 dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
 625                         orb->base.rcode);
 626                 goto out;
 627         }
 628
 629         if (orb->base.rcode != RCODE_COMPLETE) {
 630                 dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
 631                         orb->base.rcode);
 632                 goto out;
 633         }
 634
 635         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 636             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 637                 dev_err(lu_dev(lu), "error status: %d:%d\n",
 638                          STATUS_GET_RESPONSE(orb->status),
 639                          STATUS_GET_SBP_STATUS(orb->status));
 640                 goto out;
 641         }
 642
 643         retval = 0;
 644  out:
 645         dma_unmap_single(device->card->device, orb->base.request_bus,
 646                          sizeof(orb->request), DMA_TO_DEVICE);
 647  fail_mapping_request:
 648         dma_unmap_single(device->card->device, orb->response_bus,
 649                          sizeof(orb->response), DMA_FROM_DEVICE);
 650  fail_mapping_response:
 651         if (response)
 652                 memcpy(response, orb->response, sizeof(orb->response));
 653         kref_put(&orb->base.kref, free_orb);
 654
 655         return retval;
 656 }
 657
 658 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 659 {
 660         struct fw_device *device = target_parent_device(lu->tgt);
 661         __be32 d = 0;
 662
 663         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 664                            lu->tgt->node_id, lu->generation, device->max_speed,
 665                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 666                            &d, 4);
 667 }
 668
 669 static void complete_agent_reset_write_no_wait(struct fw_card *card,
 670                 int rcode, void *payload, size_t length, void *data)
 671 {
 672         kfree(data);
 673 }
 674
 675 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 676 {
 677         struct fw_device *device = target_parent_device(lu->tgt);
 678         struct fw_transaction *t;
 679         static __be32 d;
 680
 681         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 682         if (t == NULL)
 683                 return;
 684
 685         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 686                         lu->tgt->node_id, lu->generation, device->max_speed,
 687                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 688                         &d, 4, complete_agent_reset_write_no_wait, t);
 689 }
 690
 691 static inline void sbp2_allow_block(struct sbp2_target *tgt)
 692 {
 693         spin_lock_irq(&tgt->lock);
 694         --tgt->dont_block;
 695         spin_unlock_irq(&tgt->lock);
 696 }
 697
 698 /*
 699  * Blocks lu->tgt if all of the following conditions are met:
 700  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 701  *     logical units have been finished (indicated by dont_block == 0).
 702  *   - lu->generation is stale.
 703  *
 704  * Note, scsi_block_requests() must be called while holding tgt->lock,
 705  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 706  * unblock the target.
 707  */
 708 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 709 {
 710         struct sbp2_target *tgt = lu->tgt;
 711         struct fw_card *card = target_parent_device(tgt)->card;
 712         struct Scsi_Host *shost =
 713                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 714         unsigned long flags;
 715
 716         spin_lock_irqsave(&tgt->lock, flags);
 717         if (!tgt->dont_block && !lu->blocked &&
 718             lu->generation != card->generation) {
 719                 lu->blocked = true;
 720                 if (++tgt->blocked == 1)
 721                         scsi_block_requests(shost);
 722         }
 723         spin_unlock_irqrestore(&tgt->lock, flags);
 724 }
 725
 726 /*
 727  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 728  * Note, it is harmless to run scsi_unblock_requests() outside the
 729  * tgt->lock protected section.  On the other hand, running it inside
 730  * the section might clash with shost->host_lock.
 731  */
 732 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 733 {
 734         struct sbp2_target *tgt = lu->tgt;
 735         struct fw_card *card = target_parent_device(tgt)->card;
 736         struct Scsi_Host *shost =
 737                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 738         bool unblock = false;
 739
 740         spin_lock_irq(&tgt->lock);
 741         if (lu->blocked && lu->generation == card->generation) {
 742                 lu->blocked = false;
 743                 unblock = --tgt->blocked == 0;
 744         }
 745         spin_unlock_irq(&tgt->lock);
 746
 747         if (unblock)
 748                 scsi_unblock_requests(shost);
 749 }
 750
 751 /*
 752  * Prevents future blocking of tgt and unblocks it.
 753  * Note, it is harmless to run scsi_unblock_requests() outside the
 754  * tgt->lock protected section.  On the other hand, running it inside
 755  * the section might clash with shost->host_lock.
 756  */
 757 static void sbp2_unblock(struct sbp2_target *tgt)
 758 {
 759         struct Scsi_Host *shost =
 760                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 761
 762         spin_lock_irq(&tgt->lock);
 763         ++tgt->dont_block;
 764         spin_unlock_irq(&tgt->lock);
 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 /*
 781  * Write retransmit retry values into the BUSY_TIMEOUT register.
 782  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 783  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 784  *   saner value after logging into the device.
 785  * - The dual-phase retry protocol is optional to implement, and if not
 786  *   supported, writes to the dual-phase portion of the register will be
 787  *   ignored. We try to write the original 1394-1995 default here.
 788  * - In the case of devices that are also SBP-3-compliant, all writes are
 789  *   ignored, as the register is read-only, but contains single-phase retry of
 790  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 791  *   write attempt is safe and yields more consistent behavior for all devices.
 792  *
 793  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 794  * and section 6.4 of the SBP-3 spec for further details.
 795  */
 796 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 797 {
 798         struct fw_device *device = target_parent_device(lu->tgt);
 799         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 800
 801         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 802                            lu->tgt->node_id, lu->generation, device->max_speed,
 803                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
 804 }
 805
 806 static void sbp2_reconnect(struct work_struct *work);
 807
 808 static void sbp2_login(struct work_struct *work)
 809 {
 810         struct sbp2_logical_unit *lu =
 811                 container_of(work, struct sbp2_logical_unit, work.work);
 812         struct sbp2_target *tgt = lu->tgt;
 813         struct fw_device *device = target_parent_device(tgt);
 814         struct Scsi_Host *shost;
 815         struct scsi_device *sdev;
 816         struct sbp2_login_response response;
 817         int generation, node_id, local_node_id;
 818
 819         if (fw_device_is_shutdown(device))
 820                 return;
 821
 822         generation    = device->generation;
 823         smp_rmb();    /* node IDs must not be older than generation */
 824         node_id       = device->node_id;
 825         local_node_id = device->card->node_id;
 826
 827         /* If this is a re-login attempt, log out, or we might be rejected. */
 828         if (lu->has_sdev)
 829                 sbp2_send_management_orb(lu, device->node_id, generation,
 830                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 831
 832         if (sbp2_send_management_orb(lu, node_id, generation,
 833                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 834                 if (lu->retries++ < 5) {
 835                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 836                 } else {
 837                         dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
 838                                 lu->lun);
 839                         /* Let any waiting I/O fail from now on. */
 840                         sbp2_unblock(lu->tgt);
 841                 }
 842                 return;
 843         }
 844
 845         tgt->node_id      = node_id;
 846         tgt->address_high = local_node_id << 16;
 847         smp_wmb();        /* node IDs must not be older than generation */
 848         lu->generation    = generation;
 849
 850         lu->command_block_agent_address =
 851                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 852                       << 32) | be32_to_cpu(response.command_block_agent.low);
 853         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 854
 855         dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
 856                    lu->lun, lu->retries);
 857
 858         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 859         sbp2_set_busy_timeout(lu);
 860
 861         lu->workfn = sbp2_reconnect;
 862         sbp2_agent_reset(lu);
 863
 864         /* This was a re-login. */
 865         if (lu->has_sdev) {
 866                 sbp2_cancel_orbs(lu);
 867                 sbp2_conditionally_unblock(lu);
 868
 869                 return;
 870         }
 871
 872         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 873                 ssleep(SBP2_INQUIRY_DELAY);
 874
 875         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 876         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 877         /*
 878          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 879          * Therefore __scsi_add_device() will get into trouble if a bus reset
 880          * happens in parallel.  It will either fail or leave us with an
 881          * unusable sdev.  As a workaround we check for this and retry the
 882          * whole login and SCSI probing.
 883          */
 884
 885         /* Reported error during __scsi_add_device() */
 886         if (IS_ERR(sdev))
 887                 goto out_logout_login;
 888
 889         /* Unreported error during __scsi_add_device() */
 890         smp_rmb(); /* get current card generation */
 891         if (generation != device->card->generation) {
 892                 scsi_remove_device(sdev);
 893                 scsi_device_put(sdev);
 894                 goto out_logout_login;
 895         }
 896
 897         /* No error during __scsi_add_device() */
 898         lu->has_sdev = true;
 899         scsi_device_put(sdev);
 900         sbp2_allow_block(tgt);
 901
 902         return;
 903
 904  out_logout_login:
 905         smp_rmb(); /* generation may have changed */
 906         generation = device->generation;
 907         smp_rmb(); /* node_id must not be older than generation */
 908
 909         sbp2_send_management_orb(lu, device->node_id, generation,
 910                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 911         /*
 912          * If a bus reset happened, sbp2_update will have requeued
 913          * lu->work already.  Reset the work from reconnect to login.
 914          */
 915         lu->workfn = sbp2_login;
 916 }
 917
 918 static void sbp2_reconnect(struct work_struct *work)
 919 {
 920         struct sbp2_logical_unit *lu =
 921                 container_of(work, struct sbp2_logical_unit, work.work);
 922         struct sbp2_target *tgt = lu->tgt;
 923         struct fw_device *device = target_parent_device(tgt);
 924         int generation, node_id, local_node_id;
 925
 926         if (fw_device_is_shutdown(device))
 927                 return;
 928
 929         generation    = device->generation;
 930         smp_rmb();    /* node IDs must not be older than generation */
 931         node_id       = device->node_id;
 932         local_node_id = device->card->node_id;
 933
 934         if (sbp2_send_management_orb(lu, node_id, generation,
 935                                      SBP2_RECONNECT_REQUEST,
 936                                      lu->login_id, NULL) < 0) {
 937                 /*
 938                  * If reconnect was impossible even though we are in the
 939                  * current generation, fall back and try to log in again.
 940                  *
 941                  * We could check for "Function rejected" status, but
 942                  * looking at the bus generation as simpler and more general.
 943                  */
 944                 smp_rmb(); /* get current card generation */
 945                 if (generation == device->card->generation ||
 946                     lu->retries++ >= 5) {
 947                         dev_err(tgt_dev(tgt), "failed to reconnect\n");
 948                         lu->retries = 0;
 949                         lu->workfn = sbp2_login;
 950                 }
 951                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 952
 953                 return;
 954         }
 955
 956         tgt->node_id      = node_id;
 957         tgt->address_high = local_node_id << 16;
 958         smp_wmb();        /* node IDs must not be older than generation */
 959         lu->generation    = generation;
 960
 961         dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
 962                    lu->lun, lu->retries);
 963
 964         sbp2_agent_reset(lu);
 965         sbp2_cancel_orbs(lu);
 966         sbp2_conditionally_unblock(lu);
 967 }
 968
 969 static void sbp2_lu_workfn(struct work_struct *work)
 970 {
 971         struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
 972                                                 struct sbp2_logical_unit, work);
 973         lu->workfn(work);
 974 }
 975
 976 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 977 {
 978         struct sbp2_logical_unit *lu;
 979
 980         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 981         if (!lu)
 982                 return -ENOMEM;
 983
 984         lu->address_handler.length           = 0x100;
 985         lu->address_handler.address_callback = sbp2_status_write;
 986         lu->address_handler.callback_data    = lu;
 987
 988         if (fw_core_add_address_handler(&lu->address_handler,
 989                                         &fw_high_memory_region) < 0) {
 990                 kfree(lu);
 991                 return -ENOMEM;
 992         }
 993
 994         lu->tgt      = tgt;
 995         lu->lun      = lun_entry & 0xffff;
 996         lu->login_id = INVALID_LOGIN_ID;
 997         lu->retries  = 0;
 998         lu->has_sdev = false;
 999         lu->blocked  = false;
1000         ++tgt->dont_block;
1001         INIT_LIST_HEAD(&lu->orb_list);
1002         lu->workfn = sbp2_login;
1003         INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
1004
1005         list_add_tail(&lu->link, &tgt->lu_list);
1006         return 0;
1007 }
1008
1009 static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
1010                                     const u32 *leaf)
1011 {
1012         if ((leaf[0] & 0xffff0000) == 0x00020000)
1013                 tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1014 }
1015
1016 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1017                                       const u32 *directory)
1018 {
1019         struct fw_csr_iterator ci;
1020         int key, value;
1021
1022         fw_csr_iterator_init(&ci, directory);
1023         while (fw_csr_iterator_next(&ci, &key, &value))
1024                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1025                     sbp2_add_logical_unit(tgt, value) < 0)
1026                         return -ENOMEM;
1027         return 0;
1028 }
1029
1030 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1031                               u32 *model, u32 *firmware_revision)
1032 {
1033         struct fw_csr_iterator ci;
1034         int key, value;
1035
1036         fw_csr_iterator_init(&ci, directory);
1037         while (fw_csr_iterator_next(&ci, &key, &value)) {
1038                 switch (key) {
1039
1040                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1041                         tgt->management_agent_address =
1042                                         CSR_REGISTER_BASE + 4 * value;
1043                         break;
1044
1045                 case CSR_DIRECTORY_ID:
1046                         tgt->directory_id = value;
1047                         break;
1048
1049                 case CSR_MODEL:
1050                         *model = value;
1051                         break;
1052
1053                 case SBP2_CSR_FIRMWARE_REVISION:
1054                         *firmware_revision = value;
1055                         break;
1056
1057                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1058                         /* the timeout value is stored in 500ms units */
1059                         tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1060                         break;
1061
1062                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1063                         if (sbp2_add_logical_unit(tgt, value) < 0)
1064                                 return -ENOMEM;
1065                         break;
1066
1067                 case SBP2_CSR_UNIT_UNIQUE_ID:
1068                         sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1069                         break;
1070
1071                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1072                         /* Adjust for the increment in the iterator */
1073                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1074                                 return -ENOMEM;
1075                         break;
1076                 }
1077         }
1078         return 0;
1079 }
1080
1081 /*
1082  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1083  * provided in the config rom. Most devices do provide a value, which
1084  * we'll use for login management orbs, but with some sane limits.
1085  */
1086 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1087 {
1088         unsigned int timeout = tgt->mgt_orb_timeout;
1089
1090         if (timeout > 40000)
1091                 dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1092                            timeout / 1000);
1093
1094         tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1095 }
1096
1097 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1098                                   u32 firmware_revision)
1099 {
1100         int i;
1101         unsigned int w = sbp2_param_workarounds;
1102
1103         if (w)
1104                 dev_notice(tgt_dev(tgt),
1105                            "Please notify linux1394-devel@lists.sf.net "
1106                            "if you need the workarounds parameter\n");
1107
1108         if (w & SBP2_WORKAROUND_OVERRIDE)
1109                 goto out;
1110
1111         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1112
1113                 if (sbp2_workarounds_table[i].firmware_revision !=
1114                     (firmware_revision & 0xffffff00))
1115                         continue;
1116
1117                 if (sbp2_workarounds_table[i].model != model &&
1118                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1119                         continue;
1120
1121                 w |= sbp2_workarounds_table[i].workarounds;
1122                 break;
1123         }
1124  out:
1125         if (w)
1126                 dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1127                            "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1128                            w, firmware_revision, model);
1129         tgt->workarounds = w;
1130 }
1131
1132 static struct scsi_host_template scsi_driver_template;
1133 static void sbp2_remove(struct fw_unit *unit);
1134
1135 static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1136 {
1137         struct fw_device *device = fw_parent_device(unit);
1138         struct sbp2_target *tgt;
1139         struct sbp2_logical_unit *lu;
1140         struct Scsi_Host *shost;
1141         u32 model, firmware_revision;
1142
1143         /* cannot (or should not) handle targets on the local node */
1144         if (device->is_local)
1145                 return -ENODEV;
1146
1147         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1148                 WARN_ON(dma_set_max_seg_size(device->card->device,
1149                                              SBP2_MAX_SEG_SIZE));
1150
1151         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1152         if (shost == NULL)
1153                 return -ENOMEM;
1154
1155         tgt = (struct sbp2_target *)shost->hostdata;
1156         dev_set_drvdata(&unit->device, tgt);
1157         tgt->unit = unit;
1158         INIT_LIST_HEAD(&tgt->lu_list);
1159         spin_lock_init(&tgt->lock);
1160         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1161
1162         if (fw_device_enable_phys_dma(device) < 0)
1163                 goto fail_shost_put;
1164
1165         shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1166
1167         if (scsi_add_host_with_dma(shost, &unit->device,
1168                                    device->card->device) < 0)
1169                 goto fail_shost_put;
1170
1171         /* implicit directory ID */
1172         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1173                              + CSR_CONFIG_ROM) & 0xffffff;
1174
1175         firmware_revision = SBP2_ROM_VALUE_MISSING;
1176         model             = SBP2_ROM_VALUE_MISSING;
1177
1178         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1179                                &firmware_revision) < 0)
1180                 goto fail_remove;
1181
1182         sbp2_clamp_management_orb_timeout(tgt);
1183         sbp2_init_workarounds(tgt, model, firmware_revision);
1184
1185         /*
1186          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1187          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1188          * specifies the max payload size as 2 ^ (max_payload + 2), so
1189          * if we set this to max_speed + 7, we get the right value.
1190          */
1191         tgt->max_payload = min3(device->max_speed + 7, 10U,
1192                                 device->card->max_receive - 1);
1193
1194         /* Do the login in a workqueue so we can easily reschedule retries. */
1195         list_for_each_entry(lu, &tgt->lu_list, link)
1196                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1197
1198         return 0;
1199
1200  fail_remove:
1201         sbp2_remove(unit);
1202         return -ENOMEM;
1203
1204  fail_shost_put:
1205         scsi_host_put(shost);
1206         return -ENOMEM;
1207 }
1208
1209 static void sbp2_update(struct fw_unit *unit)
1210 {
1211         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1212         struct sbp2_logical_unit *lu;
1213
1214         fw_device_enable_phys_dma(fw_parent_device(unit));
1215
1216         /*
1217          * Fw-core serializes sbp2_update() against sbp2_remove().
1218          * Iteration over tgt->lu_list is therefore safe here.
1219          */
1220         list_for_each_entry(lu, &tgt->lu_list, link) {
1221                 sbp2_conditionally_block(lu);
1222                 lu->retries = 0;
1223                 sbp2_queue_work(lu, 0);
1224         }
1225 }
1226
1227 static void sbp2_remove(struct fw_unit *unit)
1228 {
1229         struct fw_device *device = fw_parent_device(unit);
1230         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1231         struct sbp2_logical_unit *lu, *next;
1232         struct Scsi_Host *shost =
1233                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1234         struct scsi_device *sdev;
1235
1236         /* prevent deadlocks */
1237         sbp2_unblock(tgt);
1238
1239         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1240                 cancel_delayed_work_sync(&lu->work);
1241                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1242                 if (sdev) {
1243                         scsi_remove_device(sdev);
1244                         scsi_device_put(sdev);
1245                 }
1246                 if (lu->login_id != INVALID_LOGIN_ID) {
1247                         int generation, node_id;
1248                         /*
1249                          * tgt->node_id may be obsolete here if we failed
1250                          * during initial login or after a bus reset where
1251                          * the topology changed.
1252                          */
1253                         generation = device->generation;
1254                         smp_rmb(); /* node_id vs. generation */
1255                         node_id    = device->node_id;
1256                         sbp2_send_management_orb(lu, node_id, generation,
1257                                                  SBP2_LOGOUT_REQUEST,
1258                                                  lu->login_id, NULL);
1259                 }
1260                 fw_core_remove_address_handler(&lu->address_handler);
1261                 list_del(&lu->link);
1262                 kfree(lu);
1263         }
1264         scsi_remove_host(shost);
1265         dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1266
1267         scsi_host_put(shost);
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   = KBUILD_MODNAME,
1287                 .bus    = &fw_bus_type,
1288         },
1289         .probe    = sbp2_probe,
1290         .update   = sbp2_update,
1291         .remove   = sbp2_remove,
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         scsi_dma_unmap(orb->cmd);
1299
1300         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1301                 dma_unmap_single(card_device, orb->page_table_bus,
1302                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1303 }
1304
1305 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1306 {
1307         int sam_status;
1308         int sfmt = (sbp2_status[0] >> 6) & 0x03;
1309
1310         if (sfmt == 2 || sfmt == 3) {
1311                 /*
1312                  * Reserved for future standardization (2) or
1313                  * Status block format vendor-dependent (3)
1314                  */
1315                 return DID_ERROR << 16;
1316         }
1317
1318         sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1319         sense_data[1] = 0x0;
1320         sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1321         sense_data[3] = sbp2_status[4];
1322         sense_data[4] = sbp2_status[5];
1323         sense_data[5] = sbp2_status[6];
1324         sense_data[6] = sbp2_status[7];
1325         sense_data[7] = 10;
1326         sense_data[8] = sbp2_status[8];
1327         sense_data[9] = sbp2_status[9];
1328         sense_data[10] = sbp2_status[10];
1329         sense_data[11] = sbp2_status[11];
1330         sense_data[12] = sbp2_status[2];
1331         sense_data[13] = sbp2_status[3];
1332         sense_data[14] = sbp2_status[12];
1333         sense_data[15] = sbp2_status[13];
1334
1335         sam_status = sbp2_status[0] & 0x3f;
1336
1337         switch (sam_status) {
1338         case SAM_STAT_GOOD:
1339         case SAM_STAT_CHECK_CONDITION:
1340         case SAM_STAT_CONDITION_MET:
1341         case SAM_STAT_BUSY:
1342         case SAM_STAT_RESERVATION_CONFLICT:
1343         case SAM_STAT_COMMAND_TERMINATED:
1344                 return DID_OK << 16 | sam_status;
1345
1346         default:
1347                 return DID_ERROR << 16;
1348         }
1349 }
1350
1351 static void complete_command_orb(struct sbp2_orb *base_orb,
1352                                  struct sbp2_status *status)
1353 {
1354         struct sbp2_command_orb *orb =
1355                 container_of(base_orb, struct sbp2_command_orb, base);
1356         struct fw_device *device = target_parent_device(base_orb->lu->tgt);
1357         int result;
1358
1359         if (status != NULL) {
1360                 if (STATUS_GET_DEAD(*status))
1361                         sbp2_agent_reset_no_wait(base_orb->lu);
1362
1363                 switch (STATUS_GET_RESPONSE(*status)) {
1364                 case SBP2_STATUS_REQUEST_COMPLETE:
1365                         result = DID_OK << 16;
1366                         break;
1367                 case SBP2_STATUS_TRANSPORT_FAILURE:
1368                         result = DID_BUS_BUSY << 16;
1369                         break;
1370                 case SBP2_STATUS_ILLEGAL_REQUEST:
1371                 case SBP2_STATUS_VENDOR_DEPENDENT:
1372                 default:
1373                         result = DID_ERROR << 16;
1374                         break;
1375                 }
1376
1377                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1378                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1379                                                            orb->cmd->sense_buffer);
1380         } else {
1381                 /*
1382                  * If the orb completes with status == NULL, something
1383                  * went wrong, typically a bus reset happened mid-orb
1384                  * or when sending the write (less likely).
1385                  */
1386                 result = DID_BUS_BUSY << 16;
1387                 sbp2_conditionally_block(base_orb->lu);
1388         }
1389
1390         dma_unmap_single(device->card->device, orb->base.request_bus,
1391                          sizeof(orb->request), DMA_TO_DEVICE);
1392         sbp2_unmap_scatterlist(device->card->device, orb);
1393
1394         orb->cmd->result = result;
1395         orb->cmd->scsi_done(orb->cmd);
1396 }
1397
1398 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1399                 struct fw_device *device, struct sbp2_logical_unit *lu)
1400 {
1401         struct scatterlist *sg = scsi_sglist(orb->cmd);
1402         int i, n;
1403
1404         n = scsi_dma_map(orb->cmd);
1405         if (n <= 0)
1406                 goto fail;
1407
1408         /*
1409          * Handle the special case where there is only one element in
1410          * the scatter list by converting it to an immediate block
1411          * request. This is also a workaround for broken devices such
1412          * as the second generation iPod which doesn't support page
1413          * tables.
1414          */
1415         if (n == 1) {
1416                 orb->request.data_descriptor.high =
1417                         cpu_to_be32(lu->tgt->address_high);
1418                 orb->request.data_descriptor.low  =
1419                         cpu_to_be32(sg_dma_address(sg));
1420                 orb->request.misc |=
1421                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1422                 return 0;
1423         }
1424
1425         for_each_sg(sg, sg, n, i) {
1426                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1427                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1428         }
1429
1430         orb->page_table_bus =
1431                 dma_map_single(device->card->device, orb->page_table,
1432                                sizeof(orb->page_table), DMA_TO_DEVICE);
1433         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1434                 goto fail_page_table;
1435
1436         /*
1437          * The data_descriptor pointer is the one case where we need
1438          * to fill in the node ID part of the address.  All other
1439          * pointers assume that the data referenced reside on the
1440          * initiator (i.e. us), but data_descriptor can refer to data
1441          * on other nodes so we need to put our ID in descriptor.high.
1442          */
1443         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1444         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1445         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1446                                          COMMAND_ORB_DATA_SIZE(n));
1447
1448         return 0;
1449
1450  fail_page_table:
1451         scsi_dma_unmap(orb->cmd);
1452  fail:
1453         return -ENOMEM;
1454 }
1455
1456 /* SCSI stack integration */
1457
1458 static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1459                                   struct scsi_cmnd *cmd)
1460 {
1461         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1462         struct fw_device *device = target_parent_device(lu->tgt);
1463         struct sbp2_command_orb *orb;
1464         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1465
1466         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1467         if (orb == NULL)
1468                 return SCSI_MLQUEUE_HOST_BUSY;
1469
1470         /* Initialize rcode to something not RCODE_COMPLETE. */
1471         orb->base.rcode = -1;
1472         kref_init(&orb->base.kref);
1473         orb->cmd = cmd;
1474         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1475         orb->request.misc = cpu_to_be32(
1476                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1477                 COMMAND_ORB_SPEED(device->max_speed) |
1478                 COMMAND_ORB_NOTIFY);
1479
1480         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1481                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1482
1483         generation = device->generation;
1484         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1485
1486         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1487                 goto out;
1488
1489         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1490
1491         orb->base.callback = complete_command_orb;
1492         orb->base.request_bus =
1493                 dma_map_single(device->card->device, &orb->request,
1494                                sizeof(orb->request), DMA_TO_DEVICE);
1495         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1496                 sbp2_unmap_scatterlist(device->card->device, orb);
1497                 goto out;
1498         }
1499
1500         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1501                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1502         retval = 0;
1503  out:
1504         kref_put(&orb->base.kref, free_orb);
1505         return retval;
1506 }
1507
1508 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1509 {
1510         struct sbp2_logical_unit *lu = sdev->hostdata;
1511
1512         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1513         if (!lu)
1514                 return -ENOSYS;
1515
1516         sdev->allow_restart = 1;
1517
1518         /*
1519          * SBP-2 does not require any alignment, but we set it anyway
1520          * for compatibility with earlier versions of this driver.
1521          */
1522         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1523
1524         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1525                 sdev->inquiry_len = 36;
1526
1527         return 0;
1528 }
1529
1530 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1531 {
1532         struct sbp2_logical_unit *lu = sdev->hostdata;
1533
1534         sdev->use_10_for_rw = 1;
1535
1536         if (sbp2_param_exclusive_login)
1537                 sdev->manage_start_stop = 1;
1538
1539         if (sdev->type == TYPE_ROM)
1540                 sdev->use_10_for_ms = 1;
1541
1542         if (sdev->type == TYPE_DISK &&
1543             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1544                 sdev->skip_ms_page_8 = 1;
1545
1546         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1547                 sdev->fix_capacity = 1;
1548
1549         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1550                 sdev->start_stop_pwr_cond = 1;
1551
1552         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1553                 blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1554
1555         return 0;
1556 }
1557
1558 /*
1559  * Called by scsi stack when something has really gone wrong.  Usually
1560  * called when a command has timed-out for some reason.
1561  */
1562 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1563 {
1564         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1565
1566         dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1567         sbp2_agent_reset(lu);
1568         sbp2_cancel_orbs(lu);
1569
1570         return SUCCESS;
1571 }
1572
1573 /*
1574  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1575  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1576  *
1577  * This is the concatenation of target port identifier and logical unit
1578  * identifier as per SAM-2...SAM-4 annex A.
1579  */
1580 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1581                         struct device_attribute *attr, char *buf)
1582 {
1583         struct scsi_device *sdev = to_scsi_device(dev);
1584         struct sbp2_logical_unit *lu;
1585
1586         if (!sdev)
1587                 return 0;
1588
1589         lu = sdev->hostdata;
1590
1591         return sprintf(buf, "%016llx:%06x:%04x\n",
1592                         (unsigned long long)lu->tgt->guid,
1593                         lu->tgt->directory_id, lu->lun);
1594 }
1595
1596 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1597
1598 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1599         &dev_attr_ieee1394_id,
1600         NULL
1601 };
1602
1603 static struct scsi_host_template scsi_driver_template = {
1604         .module                 = THIS_MODULE,
1605         .name                   = "SBP-2 IEEE-1394",
1606         .proc_name              = "sbp2",
1607         .queuecommand           = sbp2_scsi_queuecommand,
1608         .slave_alloc            = sbp2_scsi_slave_alloc,
1609         .slave_configure        = sbp2_scsi_slave_configure,
1610         .eh_abort_handler       = sbp2_scsi_abort,
1611         .this_id                = -1,
1612         .sg_tablesize           = SG_ALL,
1613         .use_clustering         = ENABLE_CLUSTERING,
1614         .can_queue              = 1,
1615         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1616 };
1617
1618 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1619 MODULE_DESCRIPTION("SCSI over IEEE1394");
1620 MODULE_LICENSE("GPL");
1621 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1622
1623 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1624 MODULE_ALIAS("sbp2");
1625
1626 static int __init sbp2_init(void)
1627 {
1628         return driver_register(&sbp2_driver.driver);
1629 }
1630
1631 static void __exit sbp2_cleanup(void)
1632 {
1633         driver_unregister(&sbp2_driver.driver);
1634 }
1635
1636 module_init(sbp2_init);
1637 module_exit(sbp2_cleanup);