Pileus Git - ~andy/linux/blob - 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         int dont_block; /* counter for each logical unit */
 178         int blocked;    /* ditto */
 179 };
 180
 181 static struct fw_device *target_parent_device(struct sbp2_target *tgt)
 182 {
 183         return fw_parent_device(tgt->unit);
 184 }
 185
 186 static const struct device *tgt_dev(const struct sbp2_target *tgt)
 187 {
 188         return &tgt->unit->device;
 189 }
 190
 191 static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
 192 {
 193         return &lu->tgt->unit->device;
 194 }
 195
 196 /* Impossible login_id, to detect logout attempt before successful login */
 197 #define INVALID_LOGIN_ID 0x10000
 198
 199 #define SBP2_ORB_TIMEOUT                2000U           /* Timeout in ms */
 200 #define SBP2_ORB_NULL                   0x80000000
 201 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
 202 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
 203
 204 /*
 205  * There is no transport protocol limit to the CDB length,  but we implement
 206  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
 207  */
 208 #define SBP2_MAX_CDB_SIZE               16
 209
 210 /*
 211  * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
 212  * for compatibility with earlier versions of this driver.
 213  */
 214 #define SBP2_MAX_SEG_SIZE               0xfffc
 215
 216 /* Unit directory keys */
 217 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
 218 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
 219 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
 220 #define SBP2_CSR_UNIT_UNIQUE_ID         0x8d
 221 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
 222
 223 /* Management orb opcodes */
 224 #define SBP2_LOGIN_REQUEST              0x0
 225 #define SBP2_QUERY_LOGINS_REQUEST       0x1
 226 #define SBP2_RECONNECT_REQUEST          0x3
 227 #define SBP2_SET_PASSWORD_REQUEST       0x4
 228 #define SBP2_LOGOUT_REQUEST             0x7
 229 #define SBP2_ABORT_TASK_REQUEST         0xb
 230 #define SBP2_ABORT_TASK_SET             0xc
 231 #define SBP2_LOGICAL_UNIT_RESET         0xe
 232 #define SBP2_TARGET_RESET_REQUEST       0xf
 233
 234 /* Offsets for command block agent registers */
 235 #define SBP2_AGENT_STATE                0x00
 236 #define SBP2_AGENT_RESET                0x04
 237 #define SBP2_ORB_POINTER                0x08
 238 #define SBP2_DOORBELL                   0x10
 239 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
 240
 241 /* Status write response codes */
 242 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
 243 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
 244 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
 245 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
 246
 247 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
 248 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
 249 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
 250 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
 251 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
 252 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
 253 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
 254 #define STATUS_GET_DATA(v)              ((v).data)
 255
 256 struct sbp2_status {
 257         u32 status;
 258         u32 orb_low;
 259         u8 data[24];
 260 };
 261
 262 struct sbp2_pointer {
 263         __be32 high;
 264         __be32 low;
 265 };
 266
 267 struct sbp2_orb {
 268         struct fw_transaction t;
 269         struct kref kref;
 270         dma_addr_t request_bus;
 271         int rcode;
 272         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 273         struct list_head link;
 274 };
 275
 276 #define MANAGEMENT_ORB_LUN(v)                   ((v))
 277 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
 278 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
 279 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
 280 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
 281 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
 282
 283 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
 284 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
 285
 286 struct sbp2_management_orb {
 287         struct sbp2_orb base;
 288         struct {
 289                 struct sbp2_pointer password;
 290                 struct sbp2_pointer response;
 291                 __be32 misc;
 292                 __be32 length;
 293                 struct sbp2_pointer status_fifo;
 294         } request;
 295         __be32 response[4];
 296         dma_addr_t response_bus;
 297         struct completion done;
 298         struct sbp2_status status;
 299 };
 300
 301 struct sbp2_login_response {
 302         __be32 misc;
 303         struct sbp2_pointer command_block_agent;
 304         __be32 reconnect_hold;
 305 };
 306 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
 307 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
 308 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
 309 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
 310 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
 311 #define COMMAND_ORB_DIRECTION           ((1) << 27)
 312 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
 313 #define COMMAND_ORB_NOTIFY              ((1) << 31)
 314
 315 struct sbp2_command_orb {
 316         struct sbp2_orb base;
 317         struct {
 318                 struct sbp2_pointer next;
 319                 struct sbp2_pointer data_descriptor;
 320                 __be32 misc;
 321                 u8 command_block[SBP2_MAX_CDB_SIZE];
 322         } request;
 323         struct scsi_cmnd *cmd;
 324         struct sbp2_logical_unit *lu;
 325
 326         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 327         dma_addr_t page_table_bus;
 328 };
 329
 330 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 331 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 332
 333 /*
 334  * List of devices with known bugs.
 335  *
 336  * The firmware_revision field, masked with 0xffff00, is the best
 337  * indicator for the type of bridge chip of a device.  It yields a few
 338  * false positives but this did not break correctly behaving devices
 339  * so far.
 340  */
 341 static const struct {
 342         u32 firmware_revision;
 343         u32 model;
 344         unsigned int workarounds;
 345 } sbp2_workarounds_table[] = {
 346         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 347                 .firmware_revision      = 0x002800,
 348                 .model                  = 0x001010,
 349                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
 350                                           SBP2_WORKAROUND_MODE_SENSE_8 |
 351                                           SBP2_WORKAROUND_POWER_CONDITION,
 352         },
 353         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 354                 .firmware_revision      = 0x002800,
 355                 .model                  = 0x000000,
 356                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 357         },
 358         /* Initio bridges, actually only needed for some older ones */ {
 359                 .firmware_revision      = 0x000200,
 360                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 361                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
 362         },
 363         /* PL-3507 bridge with Prolific firmware */ {
 364                 .firmware_revision      = 0x012800,
 365                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 366                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
 367         },
 368         /* Symbios bridge */ {
 369                 .firmware_revision      = 0xa0b800,
 370                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 371                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 372         },
 373         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 374                 .firmware_revision      = 0x002600,
 375                 .model                  = SBP2_ROM_VALUE_WILDCARD,
 376                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
 377         },
 378         /*
 379          * iPod 2nd generation: needs 128k max transfer size workaround
 380          * iPod 3rd generation: needs fix capacity workaround
 381          */
 382         {
 383                 .firmware_revision      = 0x0a2700,
 384                 .model                  = 0x000000,
 385                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
 386                                           SBP2_WORKAROUND_FIX_CAPACITY,
 387         },
 388         /* iPod 4th generation */ {
 389                 .firmware_revision      = 0x0a2700,
 390                 .model                  = 0x000021,
 391                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 392         },
 393         /* iPod mini */ {
 394                 .firmware_revision      = 0x0a2700,
 395                 .model                  = 0x000022,
 396                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 397         },
 398         /* iPod mini */ {
 399                 .firmware_revision      = 0x0a2700,
 400                 .model                  = 0x000023,
 401                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 402         },
 403         /* iPod Photo */ {
 404                 .firmware_revision      = 0x0a2700,
 405                 .model                  = 0x00007e,
 406                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
 407         }
 408 };
 409
 410 static void free_orb(struct kref *kref)
 411 {
 412         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 413
 414         kfree(orb);
 415 }
 416
 417 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 418                               int tcode, int destination, int source,
 419                               int generation, unsigned long long offset,
 420                               void *payload, size_t length, void *callback_data)
 421 {
 422         struct sbp2_logical_unit *lu = callback_data;
 423         struct sbp2_orb *orb;
 424         struct sbp2_status status;
 425         unsigned long flags;
 426
 427         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 428             length < 8 || length > sizeof(status)) {
 429                 fw_send_response(card, request, RCODE_TYPE_ERROR);
 430                 return;
 431         }
 432
 433         status.status  = be32_to_cpup(payload);
 434         status.orb_low = be32_to_cpup(payload + 4);
 435         memset(status.data, 0, sizeof(status.data));
 436         if (length > 8)
 437                 memcpy(status.data, payload + 8, length - 8);
 438
 439         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 440                 dev_notice(lu_dev(lu),
 441                            "non-ORB related status write, not handled\n");
 442                 fw_send_response(card, request, RCODE_COMPLETE);
 443                 return;
 444         }
 445
 446         /* Lookup the orb corresponding to this status write. */
 447         spin_lock_irqsave(&card->lock, flags);
 448         list_for_each_entry(orb, &lu->orb_list, link) {
 449                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
 450                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
 451                         orb->rcode = RCODE_COMPLETE;
 452                         list_del(&orb->link);
 453                         break;
 454                 }
 455         }
 456         spin_unlock_irqrestore(&card->lock, flags);
 457
 458         if (&orb->link != &lu->orb_list) {
 459                 orb->callback(orb, &status);
 460                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 461         } else {
 462                 dev_err(lu_dev(lu), "status write for unknown ORB\n");
 463         }
 464
 465         fw_send_response(card, request, RCODE_COMPLETE);
 466 }
 467
 468 static void complete_transaction(struct fw_card *card, int rcode,
 469                                  void *payload, size_t length, void *data)
 470 {
 471         struct sbp2_orb *orb = data;
 472         unsigned long flags;
 473
 474         /*
 475          * This is a little tricky.  We can get the status write for
 476          * the orb before we get this callback.  The status write
 477          * handler above will assume the orb pointer transaction was
 478          * successful and set the rcode to RCODE_COMPLETE for the orb.
 479          * So this callback only sets the rcode if it hasn't already
 480          * been set and only does the cleanup if the transaction
 481          * failed and we didn't already get a status write.
 482          */
 483         spin_lock_irqsave(&card->lock, flags);
 484
 485         if (orb->rcode == -1)
 486                 orb->rcode = rcode;
 487         if (orb->rcode != RCODE_COMPLETE) {
 488                 list_del(&orb->link);
 489                 spin_unlock_irqrestore(&card->lock, flags);
 490
 491                 orb->callback(orb, NULL);
 492                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 493         } else {
 494                 spin_unlock_irqrestore(&card->lock, flags);
 495         }
 496
 497         kref_put(&orb->kref, free_orb); /* transaction callback reference */
 498 }
 499
 500 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 501                           int node_id, int generation, u64 offset)
 502 {
 503         struct fw_device *device = target_parent_device(lu->tgt);
 504         struct sbp2_pointer orb_pointer;
 505         unsigned long flags;
 506
 507         orb_pointer.high = 0;
 508         orb_pointer.low = cpu_to_be32(orb->request_bus);
 509
 510         spin_lock_irqsave(&device->card->lock, flags);
 511         list_add_tail(&orb->link, &lu->orb_list);
 512         spin_unlock_irqrestore(&device->card->lock, flags);
 513
 514         kref_get(&orb->kref); /* transaction callback reference */
 515         kref_get(&orb->kref); /* orb callback reference */
 516
 517         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 518                         node_id, generation, device->max_speed, offset,
 519                         &orb_pointer, 8, complete_transaction, orb);
 520 }
 521
 522 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 523 {
 524         struct fw_device *device = target_parent_device(lu->tgt);
 525         struct sbp2_orb *orb, *next;
 526         struct list_head list;
 527         unsigned long flags;
 528         int retval = -ENOENT;
 529
 530         INIT_LIST_HEAD(&list);
 531         spin_lock_irqsave(&device->card->lock, flags);
 532         list_splice_init(&lu->orb_list, &list);
 533         spin_unlock_irqrestore(&device->card->lock, flags);
 534
 535         list_for_each_entry_safe(orb, next, &list, link) {
 536                 retval = 0;
 537                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
 538                         continue;
 539
 540                 orb->rcode = RCODE_CANCELLED;
 541                 orb->callback(orb, NULL);
 542                 kref_put(&orb->kref, free_orb); /* orb callback reference */
 543         }
 544
 545         return retval;
 546 }
 547
 548 static void complete_management_orb(struct sbp2_orb *base_orb,
 549                                     struct sbp2_status *status)
 550 {
 551         struct sbp2_management_orb *orb =
 552                 container_of(base_orb, struct sbp2_management_orb, base);
 553
 554         if (status)
 555                 memcpy(&orb->status, status, sizeof(*status));
 556         complete(&orb->done);
 557 }
 558
 559 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 560                                     int generation, int function,
 561                                     int lun_or_login_id, void *response)
 562 {
 563         struct fw_device *device = target_parent_device(lu->tgt);
 564         struct sbp2_management_orb *orb;
 565         unsigned int timeout;
 566         int retval = -ENOMEM;
 567
 568         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 569                 return 0;
 570
 571         orb = kzalloc(sizeof(*orb), GFP_NOIO);
 572         if (orb == NULL)
 573                 return -ENOMEM;
 574
 575         kref_init(&orb->base.kref);
 576         orb->response_bus =
 577                 dma_map_single(device->card->device, &orb->response,
 578                                sizeof(orb->response), DMA_FROM_DEVICE);
 579         if (dma_mapping_error(device->card->device, orb->response_bus))
 580                 goto fail_mapping_response;
 581
 582         orb->request.response.high = 0;
 583         orb->request.response.low  = cpu_to_be32(orb->response_bus);
 584
 585         orb->request.misc = cpu_to_be32(
 586                 MANAGEMENT_ORB_NOTIFY |
 587                 MANAGEMENT_ORB_FUNCTION(function) |
 588                 MANAGEMENT_ORB_LUN(lun_or_login_id));
 589         orb->request.length = cpu_to_be32(
 590                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 591
 592         orb->request.status_fifo.high =
 593                 cpu_to_be32(lu->address_handler.offset >> 32);
 594         orb->request.status_fifo.low  =
 595                 cpu_to_be32(lu->address_handler.offset);
 596
 597         if (function == SBP2_LOGIN_REQUEST) {
 598                 /* Ask for 2^2 == 4 seconds reconnect grace period */
 599                 orb->request.misc |= cpu_to_be32(
 600                         MANAGEMENT_ORB_RECONNECT(2) |
 601                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 602                 timeout = lu->tgt->mgt_orb_timeout;
 603         } else {
 604                 timeout = SBP2_ORB_TIMEOUT;
 605         }
 606
 607         init_completion(&orb->done);
 608         orb->base.callback = complete_management_orb;
 609
 610         orb->base.request_bus =
 611                 dma_map_single(device->card->device, &orb->request,
 612                                sizeof(orb->request), DMA_TO_DEVICE);
 613         if (dma_mapping_error(device->card->device, orb->base.request_bus))
 614                 goto fail_mapping_request;
 615
 616         sbp2_send_orb(&orb->base, lu, node_id, generation,
 617                       lu->tgt->management_agent_address);
 618
 619         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 620
 621         retval = -EIO;
 622         if (sbp2_cancel_orbs(lu) == 0) {
 623                 dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
 624                         orb->base.rcode);
 625                 goto out;
 626         }
 627
 628         if (orb->base.rcode != RCODE_COMPLETE) {
 629                 dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
 630                         orb->base.rcode);
 631                 goto out;
 632         }
 633
 634         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 635             STATUS_GET_SBP_STATUS(orb->status) != 0) {
 636                 dev_err(lu_dev(lu), "error status: %d:%d\n",
 637                          STATUS_GET_RESPONSE(orb->status),
 638                          STATUS_GET_SBP_STATUS(orb->status));
 639                 goto out;
 640         }
 641
 642         retval = 0;
 643  out:
 644         dma_unmap_single(device->card->device, orb->base.request_bus,
 645                          sizeof(orb->request), DMA_TO_DEVICE);
 646  fail_mapping_request:
 647         dma_unmap_single(device->card->device, orb->response_bus,
 648                          sizeof(orb->response), DMA_FROM_DEVICE);
 649  fail_mapping_response:
 650         if (response)
 651                 memcpy(response, orb->response, sizeof(orb->response));
 652         kref_put(&orb->base.kref, free_orb);
 653
 654         return retval;
 655 }
 656
 657 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 658 {
 659         struct fw_device *device = target_parent_device(lu->tgt);
 660         __be32 d = 0;
 661
 662         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 663                            lu->tgt->node_id, lu->generation, device->max_speed,
 664                            lu->command_block_agent_address + SBP2_AGENT_RESET,
 665                            &d, 4);
 666 }
 667
 668 static void complete_agent_reset_write_no_wait(struct fw_card *card,
 669                 int rcode, void *payload, size_t length, void *data)
 670 {
 671         kfree(data);
 672 }
 673
 674 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 675 {
 676         struct fw_device *device = target_parent_device(lu->tgt);
 677         struct fw_transaction *t;
 678         static __be32 d;
 679
 680         t = kmalloc(sizeof(*t), GFP_ATOMIC);
 681         if (t == NULL)
 682                 return;
 683
 684         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 685                         lu->tgt->node_id, lu->generation, device->max_speed,
 686                         lu->command_block_agent_address + SBP2_AGENT_RESET,
 687                         &d, 4, complete_agent_reset_write_no_wait, t);
 688 }
 689
 690 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
 691 {
 692         /*
 693          * We may access dont_block without taking card->lock here:
 694          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
 695          * are currently serialized against each other.
 696          * And a wrong result in sbp2_conditionally_block()'s access of
 697          * dont_block is rather harmless, it simply misses its first chance.
 698          */
 699         --lu->tgt->dont_block;
 700 }
 701
 702 /*
 703  * Blocks lu->tgt if all of the following conditions are met:
 704  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 705  *     logical units have been finished (indicated by dont_block == 0).
 706  *   - lu->generation is stale.
 707  *
 708  * Note, scsi_block_requests() must be called while holding card->lock,
 709  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 710  * unblock the target.
 711  */
 712 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 713 {
 714         struct sbp2_target *tgt = lu->tgt;
 715         struct fw_card *card = target_parent_device(tgt)->card;
 716         struct Scsi_Host *shost =
 717                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 718         unsigned long flags;
 719
 720         spin_lock_irqsave(&card->lock, flags);
 721         if (!tgt->dont_block && !lu->blocked &&
 722             lu->generation != card->generation) {
 723                 lu->blocked = true;
 724                 if (++tgt->blocked == 1)
 725                         scsi_block_requests(shost);
 726         }
 727         spin_unlock_irqrestore(&card->lock, flags);
 728 }
 729
 730 /*
 731  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 732  * Note, it is harmless to run scsi_unblock_requests() outside the
 733  * card->lock protected section.  On the other hand, running it inside
 734  * the section might clash with shost->host_lock.
 735  */
 736 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 737 {
 738         struct sbp2_target *tgt = lu->tgt;
 739         struct fw_card *card = target_parent_device(tgt)->card;
 740         struct Scsi_Host *shost =
 741                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 742         unsigned long flags;
 743         bool unblock = false;
 744
 745         spin_lock_irqsave(&card->lock, flags);
 746         if (lu->blocked && lu->generation == card->generation) {
 747                 lu->blocked = false;
 748                 unblock = --tgt->blocked == 0;
 749         }
 750         spin_unlock_irqrestore(&card->lock, flags);
 751
 752         if (unblock)
 753                 scsi_unblock_requests(shost);
 754 }
 755
 756 /*
 757  * Prevents future blocking of tgt and unblocks it.
 758  * Note, it is harmless to run scsi_unblock_requests() outside the
 759  * card->lock protected section.  On the other hand, running it inside
 760  * the section might clash with shost->host_lock.
 761  */
 762 static void sbp2_unblock(struct sbp2_target *tgt)
 763 {
 764         struct fw_card *card = target_parent_device(tgt)->card;
 765         struct Scsi_Host *shost =
 766                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 767         unsigned long flags;
 768
 769         spin_lock_irqsave(&card->lock, flags);
 770         ++tgt->dont_block;
 771         spin_unlock_irqrestore(&card->lock, flags);
 772
 773         scsi_unblock_requests(shost);
 774 }
 775
 776 static int sbp2_lun2int(u16 lun)
 777 {
 778         struct scsi_lun eight_bytes_lun;
 779
 780         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 781         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 782         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 783
 784         return scsilun_to_int(&eight_bytes_lun);
 785 }
 786
 787 /*
 788  * Write retransmit retry values into the BUSY_TIMEOUT register.
 789  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 790  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 791  *   saner value after logging into the device.
 792  * - The dual-phase retry protocol is optional to implement, and if not
 793  *   supported, writes to the dual-phase portion of the register will be
 794  *   ignored. We try to write the original 1394-1995 default here.
 795  * - In the case of devices that are also SBP-3-compliant, all writes are
 796  *   ignored, as the register is read-only, but contains single-phase retry of
 797  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 798  *   write attempt is safe and yields more consistent behavior for all devices.
 799  *
 800  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 801  * and section 6.4 of the SBP-3 spec for further details.
 802  */
 803 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 804 {
 805         struct fw_device *device = target_parent_device(lu->tgt);
 806         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 807
 808         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 809                            lu->tgt->node_id, lu->generation, device->max_speed,
 810                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
 811 }
 812
 813 static void sbp2_reconnect(struct work_struct *work);
 814
 815 static void sbp2_login(struct work_struct *work)
 816 {
 817         struct sbp2_logical_unit *lu =
 818                 container_of(work, struct sbp2_logical_unit, work.work);
 819         struct sbp2_target *tgt = lu->tgt;
 820         struct fw_device *device = target_parent_device(tgt);
 821         struct Scsi_Host *shost;
 822         struct scsi_device *sdev;
 823         struct sbp2_login_response response;
 824         int generation, node_id, local_node_id;
 825
 826         if (fw_device_is_shutdown(device))
 827                 return;
 828
 829         generation    = device->generation;
 830         smp_rmb();    /* node IDs must not be older than generation */
 831         node_id       = device->node_id;
 832         local_node_id = device->card->node_id;
 833
 834         /* If this is a re-login attempt, log out, or we might be rejected. */
 835         if (lu->has_sdev)
 836                 sbp2_send_management_orb(lu, device->node_id, generation,
 837                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 838
 839         if (sbp2_send_management_orb(lu, node_id, generation,
 840                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 841                 if (lu->retries++ < 5) {
 842                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 843                 } else {
 844                         dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
 845                                 lu->lun);
 846                         /* Let any waiting I/O fail from now on. */
 847                         sbp2_unblock(lu->tgt);
 848                 }
 849                 return;
 850         }
 851
 852         tgt->node_id      = node_id;
 853         tgt->address_high = local_node_id << 16;
 854         smp_wmb();        /* node IDs must not be older than generation */
 855         lu->generation    = generation;
 856
 857         lu->command_block_agent_address =
 858                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 859                       << 32) | be32_to_cpu(response.command_block_agent.low);
 860         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 861
 862         dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
 863                    lu->lun, lu->retries);
 864
 865         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 866         sbp2_set_busy_timeout(lu);
 867
 868         lu->workfn = sbp2_reconnect;
 869         sbp2_agent_reset(lu);
 870
 871         /* This was a re-login. */
 872         if (lu->has_sdev) {
 873                 sbp2_cancel_orbs(lu);
 874                 sbp2_conditionally_unblock(lu);
 875
 876                 return;
 877         }
 878
 879         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 880                 ssleep(SBP2_INQUIRY_DELAY);
 881
 882         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 883         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 884         /*
 885          * FIXME:  We are unable to perform reconnects while in sbp2_login().
 886          * Therefore __scsi_add_device() will get into trouble if a bus reset
 887          * happens in parallel.  It will either fail or leave us with an
 888          * unusable sdev.  As a workaround we check for this and retry the
 889          * whole login and SCSI probing.
 890          */
 891
 892         /* Reported error during __scsi_add_device() */
 893         if (IS_ERR(sdev))
 894                 goto out_logout_login;
 895
 896         /* Unreported error during __scsi_add_device() */
 897         smp_rmb(); /* get current card generation */
 898         if (generation != device->card->generation) {
 899                 scsi_remove_device(sdev);
 900                 scsi_device_put(sdev);
 901                 goto out_logout_login;
 902         }
 903
 904         /* No error during __scsi_add_device() */
 905         lu->has_sdev = true;
 906         scsi_device_put(sdev);
 907         sbp2_allow_block(lu);
 908
 909         return;
 910
 911  out_logout_login:
 912         smp_rmb(); /* generation may have changed */
 913         generation = device->generation;
 914         smp_rmb(); /* node_id must not be older than generation */
 915
 916         sbp2_send_management_orb(lu, device->node_id, generation,
 917                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 918         /*
 919          * If a bus reset happened, sbp2_update will have requeued
 920          * lu->work already.  Reset the work from reconnect to login.
 921          */
 922         lu->workfn = sbp2_login;
 923 }
 924
 925 static void sbp2_reconnect(struct work_struct *work)
 926 {
 927         struct sbp2_logical_unit *lu =
 928                 container_of(work, struct sbp2_logical_unit, work.work);
 929         struct sbp2_target *tgt = lu->tgt;
 930         struct fw_device *device = target_parent_device(tgt);
 931         int generation, node_id, local_node_id;
 932
 933         if (fw_device_is_shutdown(device))
 934                 return;
 935
 936         generation    = device->generation;
 937         smp_rmb();    /* node IDs must not be older than generation */
 938         node_id       = device->node_id;
 939         local_node_id = device->card->node_id;
 940
 941         if (sbp2_send_management_orb(lu, node_id, generation,
 942                                      SBP2_RECONNECT_REQUEST,
 943                                      lu->login_id, NULL) < 0) {
 944                 /*
 945                  * If reconnect was impossible even though we are in the
 946                  * current generation, fall back and try to log in again.
 947                  *
 948                  * We could check for "Function rejected" status, but
 949                  * looking at the bus generation as simpler and more general.
 950                  */
 951                 smp_rmb(); /* get current card generation */
 952                 if (generation == device->card->generation ||
 953                     lu->retries++ >= 5) {
 954                         dev_err(tgt_dev(tgt), "failed to reconnect\n");
 955                         lu->retries = 0;
 956                         lu->workfn = sbp2_login;
 957                 }
 958                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 959
 960                 return;
 961         }
 962
 963         tgt->node_id      = node_id;
 964         tgt->address_high = local_node_id << 16;
 965         smp_wmb();        /* node IDs must not be older than generation */
 966         lu->generation    = generation;
 967
 968         dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
 969                    lu->lun, lu->retries);
 970
 971         sbp2_agent_reset(lu);
 972         sbp2_cancel_orbs(lu);
 973         sbp2_conditionally_unblock(lu);
 974 }
 975
 976 static void sbp2_lu_workfn(struct work_struct *work)
 977 {
 978         struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
 979                                                 struct sbp2_logical_unit, work);
 980         lu->workfn(work);
 981 }
 982
 983 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 984 {
 985         struct sbp2_logical_unit *lu;
 986
 987         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 988         if (!lu)
 989                 return -ENOMEM;
 990
 991         lu->address_handler.length           = 0x100;
 992         lu->address_handler.address_callback = sbp2_status_write;
 993         lu->address_handler.callback_data    = lu;
 994
 995         if (fw_core_add_address_handler(&lu->address_handler,
 996                                         &fw_high_memory_region) < 0) {
 997                 kfree(lu);
 998                 return -ENOMEM;
 999         }
1000
1001         lu->tgt      = tgt;
1002         lu->lun      = lun_entry & 0xffff;
1003         lu->login_id = INVALID_LOGIN_ID;
1004         lu->retries  = 0;
1005         lu->has_sdev = false;
1006         lu->blocked  = false;
1007         ++tgt->dont_block;
1008         INIT_LIST_HEAD(&lu->orb_list);
1009         lu->workfn = sbp2_login;
1010         INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
1011
1012         list_add_tail(&lu->link, &tgt->lu_list);
1013         return 0;
1014 }
1015
1016 static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
1017                                     const u32 *leaf)
1018 {
1019         if ((leaf[0] & 0xffff0000) == 0x00020000)
1020                 tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1021 }
1022
1023 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1024                                       const u32 *directory)
1025 {
1026         struct fw_csr_iterator ci;
1027         int key, value;
1028
1029         fw_csr_iterator_init(&ci, directory);
1030         while (fw_csr_iterator_next(&ci, &key, &value))
1031                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1032                     sbp2_add_logical_unit(tgt, value) < 0)
1033                         return -ENOMEM;
1034         return 0;
1035 }
1036
1037 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1038                               u32 *model, u32 *firmware_revision)
1039 {
1040         struct fw_csr_iterator ci;
1041         int key, value;
1042
1043         fw_csr_iterator_init(&ci, directory);
1044         while (fw_csr_iterator_next(&ci, &key, &value)) {
1045                 switch (key) {
1046
1047                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1048                         tgt->management_agent_address =
1049                                         CSR_REGISTER_BASE + 4 * value;
1050                         break;
1051
1052                 case CSR_DIRECTORY_ID:
1053                         tgt->directory_id = value;
1054                         break;
1055
1056                 case CSR_MODEL:
1057                         *model = value;
1058                         break;
1059
1060                 case SBP2_CSR_FIRMWARE_REVISION:
1061                         *firmware_revision = value;
1062                         break;
1063
1064                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1065                         /* the timeout value is stored in 500ms units */
1066                         tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
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_UNIT_UNIQUE_ID:
1075                         sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1076                         break;
1077
1078                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1079                         /* Adjust for the increment in the iterator */
1080                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1081                                 return -ENOMEM;
1082                         break;
1083                 }
1084         }
1085         return 0;
1086 }
1087
1088 /*
1089  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1090  * provided in the config rom. Most devices do provide a value, which
1091  * we'll use for login management orbs, but with some sane limits.
1092  */
1093 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1094 {
1095         unsigned int timeout = tgt->mgt_orb_timeout;
1096
1097         if (timeout > 40000)
1098                 dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1099                            timeout / 1000);
1100
1101         tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1102 }
1103
1104 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1105                                   u32 firmware_revision)
1106 {
1107         int i;
1108         unsigned int w = sbp2_param_workarounds;
1109
1110         if (w)
1111                 dev_notice(tgt_dev(tgt),
1112                            "Please notify linux1394-devel@lists.sf.net "
1113                            "if you need the workarounds parameter\n");
1114
1115         if (w & SBP2_WORKAROUND_OVERRIDE)
1116                 goto out;
1117
1118         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1119
1120                 if (sbp2_workarounds_table[i].firmware_revision !=
1121                     (firmware_revision & 0xffffff00))
1122                         continue;
1123
1124                 if (sbp2_workarounds_table[i].model != model &&
1125                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1126                         continue;
1127
1128                 w |= sbp2_workarounds_table[i].workarounds;
1129                 break;
1130         }
1131  out:
1132         if (w)
1133                 dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1134                            "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1135                            w, firmware_revision, model);
1136         tgt->workarounds = w;
1137 }
1138
1139 static struct scsi_host_template scsi_driver_template;
1140 static void sbp2_remove(struct fw_unit *unit);
1141
1142 static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1143 {
1144         struct fw_device *device = fw_parent_device(unit);
1145         struct sbp2_target *tgt;
1146         struct sbp2_logical_unit *lu;
1147         struct Scsi_Host *shost;
1148         u32 model, firmware_revision;
1149
1150         /* cannot (or should not) handle targets on the local node */
1151         if (device->is_local)
1152                 return -ENODEV;
1153
1154         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1155                 WARN_ON(dma_set_max_seg_size(device->card->device,
1156                                              SBP2_MAX_SEG_SIZE));
1157
1158         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1159         if (shost == NULL)
1160                 return -ENOMEM;
1161
1162         tgt = (struct sbp2_target *)shost->hostdata;
1163         dev_set_drvdata(&unit->device, tgt);
1164         tgt->unit = unit;
1165         INIT_LIST_HEAD(&tgt->lu_list);
1166         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1167
1168         if (fw_device_enable_phys_dma(device) < 0)
1169                 goto fail_shost_put;
1170
1171         shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1172
1173         if (scsi_add_host_with_dma(shost, &unit->device,
1174                                    device->card->device) < 0)
1175                 goto fail_shost_put;
1176
1177         /* implicit directory ID */
1178         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1179                              + CSR_CONFIG_ROM) & 0xffffff;
1180
1181         firmware_revision = SBP2_ROM_VALUE_MISSING;
1182         model             = SBP2_ROM_VALUE_MISSING;
1183
1184         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1185                                &firmware_revision) < 0)
1186                 goto fail_remove;
1187
1188         sbp2_clamp_management_orb_timeout(tgt);
1189         sbp2_init_workarounds(tgt, model, firmware_revision);
1190
1191         /*
1192          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1193          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1194          * specifies the max payload size as 2 ^ (max_payload + 2), so
1195          * if we set this to max_speed + 7, we get the right value.
1196          */
1197         tgt->max_payload = min3(device->max_speed + 7, 10U,
1198                                 device->card->max_receive - 1);
1199
1200         /* Do the login in a workqueue so we can easily reschedule retries. */
1201         list_for_each_entry(lu, &tgt->lu_list, link)
1202                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1203
1204         return 0;
1205
1206  fail_remove:
1207         sbp2_remove(unit);
1208         return -ENOMEM;
1209
1210  fail_shost_put:
1211         scsi_host_put(shost);
1212         return -ENOMEM;
1213 }
1214
1215 static void sbp2_update(struct fw_unit *unit)
1216 {
1217         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1218         struct sbp2_logical_unit *lu;
1219
1220         fw_device_enable_phys_dma(fw_parent_device(unit));
1221
1222         /*
1223          * Fw-core serializes sbp2_update() against sbp2_remove().
1224          * Iteration over tgt->lu_list is therefore safe here.
1225          */
1226         list_for_each_entry(lu, &tgt->lu_list, link) {
1227                 sbp2_conditionally_block(lu);
1228                 lu->retries = 0;
1229                 sbp2_queue_work(lu, 0);
1230         }
1231 }
1232
1233 static void sbp2_remove(struct fw_unit *unit)
1234 {
1235         struct fw_device *device = fw_parent_device(unit);
1236         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1237         struct sbp2_logical_unit *lu, *next;
1238         struct Scsi_Host *shost =
1239                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1240         struct scsi_device *sdev;
1241
1242         /* prevent deadlocks */
1243         sbp2_unblock(tgt);
1244
1245         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1246                 cancel_delayed_work_sync(&lu->work);
1247                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1248                 if (sdev) {
1249                         scsi_remove_device(sdev);
1250                         scsi_device_put(sdev);
1251                 }
1252                 if (lu->login_id != INVALID_LOGIN_ID) {
1253                         int generation, node_id;
1254                         /*
1255                          * tgt->node_id may be obsolete here if we failed
1256                          * during initial login or after a bus reset where
1257                          * the topology changed.
1258                          */
1259                         generation = device->generation;
1260                         smp_rmb(); /* node_id vs. generation */
1261                         node_id    = device->node_id;
1262                         sbp2_send_management_orb(lu, node_id, generation,
1263                                                  SBP2_LOGOUT_REQUEST,
1264                                                  lu->login_id, NULL);
1265                 }
1266                 fw_core_remove_address_handler(&lu->address_handler);
1267                 list_del(&lu->link);
1268                 kfree(lu);
1269         }
1270         scsi_remove_host(shost);
1271         dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1272
1273         scsi_host_put(shost);
1274 }
1275
1276 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1277 #define SBP2_SW_VERSION_ENTRY   0x00010483
1278
1279 static const struct ieee1394_device_id sbp2_id_table[] = {
1280         {
1281                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1282                                 IEEE1394_MATCH_VERSION,
1283                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1284                 .version      = SBP2_SW_VERSION_ENTRY,
1285         },
1286         { }
1287 };
1288
1289 static struct fw_driver sbp2_driver = {
1290         .driver   = {
1291                 .owner  = THIS_MODULE,
1292                 .name   = KBUILD_MODNAME,
1293                 .bus    = &fw_bus_type,
1294         },
1295         .probe    = sbp2_probe,
1296         .update   = sbp2_update,
1297         .remove   = sbp2_remove,
1298         .id_table = sbp2_id_table,
1299 };
1300
1301 static void sbp2_unmap_scatterlist(struct device *card_device,
1302                                    struct sbp2_command_orb *orb)
1303 {
1304         scsi_dma_unmap(orb->cmd);
1305
1306         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1307                 dma_unmap_single(card_device, orb->page_table_bus,
1308                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1309 }
1310
1311 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1312 {
1313         int sam_status;
1314         int sfmt = (sbp2_status[0] >> 6) & 0x03;
1315
1316         if (sfmt == 2 || sfmt == 3) {
1317                 /*
1318                  * Reserved for future standardization (2) or
1319                  * Status block format vendor-dependent (3)
1320                  */
1321                 return DID_ERROR << 16;
1322         }
1323
1324         sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1325         sense_data[1] = 0x0;
1326         sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1327         sense_data[3] = sbp2_status[4];
1328         sense_data[4] = sbp2_status[5];
1329         sense_data[5] = sbp2_status[6];
1330         sense_data[6] = sbp2_status[7];
1331         sense_data[7] = 10;
1332         sense_data[8] = sbp2_status[8];
1333         sense_data[9] = sbp2_status[9];
1334         sense_data[10] = sbp2_status[10];
1335         sense_data[11] = sbp2_status[11];
1336         sense_data[12] = sbp2_status[2];
1337         sense_data[13] = sbp2_status[3];
1338         sense_data[14] = sbp2_status[12];
1339         sense_data[15] = sbp2_status[13];
1340
1341         sam_status = sbp2_status[0] & 0x3f;
1342
1343         switch (sam_status) {
1344         case SAM_STAT_GOOD:
1345         case SAM_STAT_CHECK_CONDITION:
1346         case SAM_STAT_CONDITION_MET:
1347         case SAM_STAT_BUSY:
1348         case SAM_STAT_RESERVATION_CONFLICT:
1349         case SAM_STAT_COMMAND_TERMINATED:
1350                 return DID_OK << 16 | sam_status;
1351
1352         default:
1353                 return DID_ERROR << 16;
1354         }
1355 }
1356
1357 static void complete_command_orb(struct sbp2_orb *base_orb,
1358                                  struct sbp2_status *status)
1359 {
1360         struct sbp2_command_orb *orb =
1361                 container_of(base_orb, struct sbp2_command_orb, base);
1362         struct fw_device *device = target_parent_device(orb->lu->tgt);
1363         int result;
1364
1365         if (status != NULL) {
1366                 if (STATUS_GET_DEAD(*status))
1367                         sbp2_agent_reset_no_wait(orb->lu);
1368
1369                 switch (STATUS_GET_RESPONSE(*status)) {
1370                 case SBP2_STATUS_REQUEST_COMPLETE:
1371                         result = DID_OK << 16;
1372                         break;
1373                 case SBP2_STATUS_TRANSPORT_FAILURE:
1374                         result = DID_BUS_BUSY << 16;
1375                         break;
1376                 case SBP2_STATUS_ILLEGAL_REQUEST:
1377                 case SBP2_STATUS_VENDOR_DEPENDENT:
1378                 default:
1379                         result = DID_ERROR << 16;
1380                         break;
1381                 }
1382
1383                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1384                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1385                                                            orb->cmd->sense_buffer);
1386         } else {
1387                 /*
1388                  * If the orb completes with status == NULL, something
1389                  * went wrong, typically a bus reset happened mid-orb
1390                  * or when sending the write (less likely).
1391                  */
1392                 result = DID_BUS_BUSY << 16;
1393                 sbp2_conditionally_block(orb->lu);
1394         }
1395
1396         dma_unmap_single(device->card->device, orb->base.request_bus,
1397                          sizeof(orb->request), DMA_TO_DEVICE);
1398         sbp2_unmap_scatterlist(device->card->device, orb);
1399
1400         orb->cmd->result = result;
1401         orb->cmd->scsi_done(orb->cmd);
1402 }
1403
1404 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1405                 struct fw_device *device, struct sbp2_logical_unit *lu)
1406 {
1407         struct scatterlist *sg = scsi_sglist(orb->cmd);
1408         int i, n;
1409
1410         n = scsi_dma_map(orb->cmd);
1411         if (n <= 0)
1412                 goto fail;
1413
1414         /*
1415          * Handle the special case where there is only one element in
1416          * the scatter list by converting it to an immediate block
1417          * request. This is also a workaround for broken devices such
1418          * as the second generation iPod which doesn't support page
1419          * tables.
1420          */
1421         if (n == 1) {
1422                 orb->request.data_descriptor.high =
1423                         cpu_to_be32(lu->tgt->address_high);
1424                 orb->request.data_descriptor.low  =
1425                         cpu_to_be32(sg_dma_address(sg));
1426                 orb->request.misc |=
1427                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1428                 return 0;
1429         }
1430
1431         for_each_sg(sg, sg, n, i) {
1432                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1433                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1434         }
1435
1436         orb->page_table_bus =
1437                 dma_map_single(device->card->device, orb->page_table,
1438                                sizeof(orb->page_table), DMA_TO_DEVICE);
1439         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1440                 goto fail_page_table;
1441
1442         /*
1443          * The data_descriptor pointer is the one case where we need
1444          * to fill in the node ID part of the address.  All other
1445          * pointers assume that the data referenced reside on the
1446          * initiator (i.e. us), but data_descriptor can refer to data
1447          * on other nodes so we need to put our ID in descriptor.high.
1448          */
1449         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1450         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1451         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1452                                          COMMAND_ORB_DATA_SIZE(n));
1453
1454         return 0;
1455
1456  fail_page_table:
1457         scsi_dma_unmap(orb->cmd);
1458  fail:
1459         return -ENOMEM;
1460 }
1461
1462 /* SCSI stack integration */
1463
1464 static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1465                                   struct scsi_cmnd *cmd)
1466 {
1467         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1468         struct fw_device *device = target_parent_device(lu->tgt);
1469         struct sbp2_command_orb *orb;
1470         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1471
1472         /*
1473          * Bidirectional commands are not yet implemented, and unknown
1474          * transfer direction not handled.
1475          */
1476         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1477                 dev_err(lu_dev(lu), "cannot handle bidirectional command\n");
1478                 cmd->result = DID_ERROR << 16;
1479                 cmd->scsi_done(cmd);
1480                 return 0;
1481         }
1482
1483         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1484         if (orb == NULL)
1485                 return SCSI_MLQUEUE_HOST_BUSY;
1486
1487         /* Initialize rcode to something not RCODE_COMPLETE. */
1488         orb->base.rcode = -1;
1489         kref_init(&orb->base.kref);
1490         orb->lu = lu;
1491         orb->cmd = cmd;
1492         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1493         orb->request.misc = cpu_to_be32(
1494                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1495                 COMMAND_ORB_SPEED(device->max_speed) |
1496                 COMMAND_ORB_NOTIFY);
1497
1498         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1499                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1500
1501         generation = device->generation;
1502         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1503
1504         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1505                 goto out;
1506
1507         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1508
1509         orb->base.callback = complete_command_orb;
1510         orb->base.request_bus =
1511                 dma_map_single(device->card->device, &orb->request,
1512                                sizeof(orb->request), DMA_TO_DEVICE);
1513         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1514                 sbp2_unmap_scatterlist(device->card->device, orb);
1515                 goto out;
1516         }
1517
1518         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1519                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1520         retval = 0;
1521  out:
1522         kref_put(&orb->base.kref, free_orb);
1523         return retval;
1524 }
1525
1526 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1527 {
1528         struct sbp2_logical_unit *lu = sdev->hostdata;
1529
1530         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1531         if (!lu)
1532                 return -ENOSYS;
1533
1534         sdev->allow_restart = 1;
1535
1536         /*
1537          * SBP-2 does not require any alignment, but we set it anyway
1538          * for compatibility with earlier versions of this driver.
1539          */
1540         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1541
1542         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1543                 sdev->inquiry_len = 36;
1544
1545         return 0;
1546 }
1547
1548 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1549 {
1550         struct sbp2_logical_unit *lu = sdev->hostdata;
1551
1552         sdev->use_10_for_rw = 1;
1553
1554         if (sbp2_param_exclusive_login)
1555                 sdev->manage_start_stop = 1;
1556
1557         if (sdev->type == TYPE_ROM)
1558                 sdev->use_10_for_ms = 1;
1559
1560         if (sdev->type == TYPE_DISK &&
1561             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1562                 sdev->skip_ms_page_8 = 1;
1563
1564         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1565                 sdev->fix_capacity = 1;
1566
1567         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1568                 sdev->start_stop_pwr_cond = 1;
1569
1570         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1571                 blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1572
1573         return 0;
1574 }
1575
1576 /*
1577  * Called by scsi stack when something has really gone wrong.  Usually
1578  * called when a command has timed-out for some reason.
1579  */
1580 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1581 {
1582         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1583
1584         dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1585         sbp2_agent_reset(lu);
1586         sbp2_cancel_orbs(lu);
1587
1588         return SUCCESS;
1589 }
1590
1591 /*
1592  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1593  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1594  *
1595  * This is the concatenation of target port identifier and logical unit
1596  * identifier as per SAM-2...SAM-4 annex A.
1597  */
1598 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1599                         struct device_attribute *attr, char *buf)
1600 {
1601         struct scsi_device *sdev = to_scsi_device(dev);
1602         struct sbp2_logical_unit *lu;
1603
1604         if (!sdev)
1605                 return 0;
1606
1607         lu = sdev->hostdata;
1608
1609         return sprintf(buf, "%016llx:%06x:%04x\n",
1610                         (unsigned long long)lu->tgt->guid,
1611                         lu->tgt->directory_id, lu->lun);
1612 }
1613
1614 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1615
1616 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1617         &dev_attr_ieee1394_id,
1618         NULL
1619 };
1620
1621 static struct scsi_host_template scsi_driver_template = {
1622         .module                 = THIS_MODULE,
1623         .name                   = "SBP-2 IEEE-1394",
1624         .proc_name              = "sbp2",
1625         .queuecommand           = sbp2_scsi_queuecommand,
1626         .slave_alloc            = sbp2_scsi_slave_alloc,
1627         .slave_configure        = sbp2_scsi_slave_configure,
1628         .eh_abort_handler       = sbp2_scsi_abort,
1629         .this_id                = -1,
1630         .sg_tablesize           = SG_ALL,
1631         .use_clustering         = ENABLE_CLUSTERING,
1632         .cmd_per_lun            = 1,
1633         .can_queue              = 1,
1634         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1635 };
1636
1637 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1638 MODULE_DESCRIPTION("SCSI over IEEE1394");
1639 MODULE_LICENSE("GPL");
1640 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1641
1642 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1643 MODULE_ALIAS("sbp2");
1644
1645 static int __init sbp2_init(void)
1646 {
1647         return driver_register(&sbp2_driver.driver);
1648 }
1649
1650 static void __exit sbp2_cleanup(void)
1651 {
1652         driver_unregister(&sbp2_driver.driver);
1653 }
1654
1655 module_init(sbp2_init);
1656 module_exit(sbp2_cleanup);