1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * SBP2 driver (SCSI over IEEE1394)
   4 *
   5 * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   6 */
   7
   8/*
   9 * The basic structure of this driver is based on the old storage driver,
  10 * drivers/ieee1394/sbp2.c, originally written by
  11 *     James Goodwin <jamesg@filanet.com>
  12 * with later contributions and ongoing maintenance from
  13 *     Ben Collins <bcollins@debian.org>,
  14 *     Stefan Richter <stefanr@s5r6.in-berlin.de>
  15 * and many others.
  16 */
  17
  18#include <linux/blkdev.h>
  19#include <linux/bug.h>
  20#include <linux/completion.h>
  21#include <linux/delay.h>
  22#include <linux/device.h>
  23#include <linux/dma-mapping.h>
  24#include <linux/firewire.h>
  25#include <linux/firewire-constants.h>
  26#include <linux/init.h>
  27#include <linux/jiffies.h>
  28#include <linux/kernel.h>
  29#include <linux/kref.h>
  30#include <linux/list.h>
  31#include <linux/mod_devicetable.h>
  32#include <linux/module.h>
  33#include <linux/moduleparam.h>
  34#include <linux/scatterlist.h>
  35#include <linux/slab.h>
  36#include <linux/spinlock.h>
  37#include <linux/string.h>
  38#include <linux/stringify.h>
  39#include <linux/workqueue.h>
  40
  41#include <asm/byteorder.h>
  42
  43#include <scsi/scsi.h>
  44#include <scsi/scsi_cmnd.h>
  45#include <scsi/scsi_device.h>
  46#include <scsi/scsi_host.h>
  47
  48/*
  49 * So far only bridges from Oxford Semiconductor are known to support
  50 * concurrent logins. Depending on firmware, four or two concurrent logins
  51 * are possible on OXFW911 and newer Oxsemi bridges.
  52 *
  53 * Concurrent logins are useful together with cluster filesystems.
  54 */
  55static bool sbp2_param_exclusive_login = 1;
  56module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
  57MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
  58		 "(default = Y, use N for concurrent initiators)");
  59
  60/*
  61 * Flags for firmware oddities
  62 *
  63 * - 128kB max transfer
  64 *   Limit transfer size. Necessary for some old bridges.
  65 *
  66 * - 36 byte inquiry
  67 *   When scsi_mod probes the device, let the inquiry command look like that
  68 *   from MS Windows.
  69 *
  70 * - skip mode page 8
  71 *   Suppress sending of mode_sense for mode page 8 if the device pretends to
  72 *   support the SCSI Primary Block commands instead of Reduced Block Commands.
  73 *
  74 * - fix capacity
  75 *   Tell sd_mod to correct the last sector number reported by read_capacity.
  76 *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
  77 *   Don't use this with devices which don't have this bug.
  78 *
  79 * - delay inquiry
  80 *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
  81 *
  82 * - power condition
  83 *   Set the power condition field in the START STOP UNIT commands sent by
  84 *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
  85 *   Some disks need this to spin down or to resume properly.
  86 *
  87 * - override internal blacklist
  88 *   Instead of adding to the built-in blacklist, use only the workarounds
  89 *   specified in the module load parameter.
  90 *   Useful if a blacklist entry interfered with a non-broken device.
  91 */
  92#define SBP2_WORKAROUND_128K_MAX_TRANS	0x1
  93#define SBP2_WORKAROUND_INQUIRY_36	0x2
  94#define SBP2_WORKAROUND_MODE_SENSE_8	0x4
  95#define SBP2_WORKAROUND_FIX_CAPACITY	0x8
  96#define SBP2_WORKAROUND_DELAY_INQUIRY	0x10
  97#define SBP2_INQUIRY_DELAY		12
  98#define SBP2_WORKAROUND_POWER_CONDITION	0x20
  99#define SBP2_WORKAROUND_OVERRIDE	0x100
 100
 101static int sbp2_param_workarounds;
 102module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
 103MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
 104	", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
 105	", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
 106	", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
 107	", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
 108	", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
 109	", set power condition in start stop unit = "
 110				  __stringify(SBP2_WORKAROUND_POWER_CONDITION)
 111	", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
 112	", or a combination)");
 113
 114/*
 115 * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
 116 * and one struct scsi_device per sbp2_logical_unit.
 117 */
 118struct sbp2_logical_unit {
 119	struct sbp2_target *tgt;
 120	struct list_head link;
 121	struct fw_address_handler address_handler;
 122	struct list_head orb_list;
 123
 124	u64 command_block_agent_address;
 125	u16 lun;
 126	int login_id;
 127
 128	/*
 129	 * The generation is updated once we've logged in or reconnected
 130	 * to the logical unit.  Thus, I/O to the device will automatically
 131	 * fail and get retried if it happens in a window where the device
 132	 * is not ready, e.g. after a bus reset but before we reconnect.
 133	 */
 134	int generation;
 135	int retries;
 136	work_func_t workfn;
 137	struct delayed_work work;
 138	bool has_sdev;
 139	bool blocked;
 140};
 141
 142static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
 143{
 144	queue_delayed_work(fw_workqueue, &lu->work, delay);
 145}
 146
 147/*
 148 * We create one struct sbp2_target per IEEE 1212 Unit Directory
 149 * and one struct Scsi_Host per sbp2_target.
 150 */
 151struct sbp2_target {
 152	struct fw_unit *unit;
 153	struct list_head lu_list;
 154
 155	u64 management_agent_address;
 156	u64 guid;
 157	int directory_id;
 158	int node_id;
 159	int address_high;
 160	unsigned int workarounds;
 161	unsigned int mgt_orb_timeout;
 162	unsigned int max_payload;
 163
 164	spinlock_t lock;
 165	int dont_block;	/* counter for each logical unit */
 166	int blocked;	/* ditto */
 167};
 168
 169static struct fw_device *target_parent_device(struct sbp2_target *tgt)
 170{
 171	return fw_parent_device(tgt->unit);
 172}
 173
 174static const struct device *tgt_dev(const struct sbp2_target *tgt)
 175{
 176	return &tgt->unit->device;
 177}
 178
 179static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
 180{
 181	return &lu->tgt->unit->device;
 182}
 183
 184/* Impossible login_id, to detect logout attempt before successful login */
 185#define INVALID_LOGIN_ID 0x10000
 186
 187#define SBP2_ORB_TIMEOUT		2000U		/* Timeout in ms */
 188#define SBP2_ORB_NULL			0x80000000
 189#define SBP2_RETRY_LIMIT		0xf		/* 15 retries */
 190#define SBP2_CYCLE_LIMIT		(0xc8 << 12)	/* 200 125us cycles */
 191
 192/*
 193 * There is no transport protocol limit to the CDB length,  but we implement
 194 * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
 195 */
 196#define SBP2_MAX_CDB_SIZE		16
 197
 198/*
 199 * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
 200 * for compatibility with earlier versions of this driver.
 201 */
 202#define SBP2_MAX_SEG_SIZE		0xfffc
 203
 204/* Unit directory keys */
 205#define SBP2_CSR_UNIT_CHARACTERISTICS	0x3a
 206#define SBP2_CSR_FIRMWARE_REVISION	0x3c
 207#define SBP2_CSR_LOGICAL_UNIT_NUMBER	0x14
 208#define SBP2_CSR_UNIT_UNIQUE_ID		0x8d
 209#define SBP2_CSR_LOGICAL_UNIT_DIRECTORY	0xd4
 210
 211/* Management orb opcodes */
 212#define SBP2_LOGIN_REQUEST		0x0
 213#define SBP2_QUERY_LOGINS_REQUEST	0x1
 214#define SBP2_RECONNECT_REQUEST		0x3
 215#define SBP2_SET_PASSWORD_REQUEST	0x4
 216#define SBP2_LOGOUT_REQUEST		0x7
 217#define SBP2_ABORT_TASK_REQUEST		0xb
 218#define SBP2_ABORT_TASK_SET		0xc
 219#define SBP2_LOGICAL_UNIT_RESET		0xe
 220#define SBP2_TARGET_RESET_REQUEST	0xf
 221
 222/* Offsets for command block agent registers */
 223#define SBP2_AGENT_STATE		0x00
 224#define SBP2_AGENT_RESET		0x04
 225#define SBP2_ORB_POINTER		0x08
 226#define SBP2_DOORBELL			0x10
 227#define SBP2_UNSOLICITED_STATUS_ENABLE	0x14
 228
 229/* Status write response codes */
 230#define SBP2_STATUS_REQUEST_COMPLETE	0x0
 231#define SBP2_STATUS_TRANSPORT_FAILURE	0x1
 232#define SBP2_STATUS_ILLEGAL_REQUEST	0x2
 233#define SBP2_STATUS_VENDOR_DEPENDENT	0x3
 234
 235#define STATUS_GET_ORB_HIGH(v)		((v).status & 0xffff)
 236#define STATUS_GET_SBP_STATUS(v)	(((v).status >> 16) & 0xff)
 237#define STATUS_GET_LEN(v)		(((v).status >> 24) & 0x07)
 238#define STATUS_GET_DEAD(v)		(((v).status >> 27) & 0x01)
 239#define STATUS_GET_RESPONSE(v)		(((v).status >> 28) & 0x03)
 240#define STATUS_GET_SOURCE(v)		(((v).status >> 30) & 0x03)
 241#define STATUS_GET_ORB_LOW(v)		((v).orb_low)
 242#define STATUS_GET_DATA(v)		((v).data)
 243
 244struct sbp2_status {
 245	u32 status;
 246	u32 orb_low;
 247	u8 data[24];
 248};
 249
 250struct sbp2_pointer {
 251	__be32 high;
 252	__be32 low;
 253};
 254
 255struct sbp2_orb {
 256	struct fw_transaction t;
 257	struct kref kref;
 258	dma_addr_t request_bus;
 259	int rcode;
 260	void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
 261	struct sbp2_logical_unit *lu;
 262	struct list_head link;
 263};
 264
 265#define MANAGEMENT_ORB_LUN(v)			((v))
 266#define MANAGEMENT_ORB_FUNCTION(v)		((v) << 16)
 267#define MANAGEMENT_ORB_RECONNECT(v)		((v) << 20)
 268#define MANAGEMENT_ORB_EXCLUSIVE(v)		((v) ? 1 << 28 : 0)
 269#define MANAGEMENT_ORB_REQUEST_FORMAT(v)	((v) << 29)
 270#define MANAGEMENT_ORB_NOTIFY			((1) << 31)
 271
 272#define MANAGEMENT_ORB_RESPONSE_LENGTH(v)	((v))
 273#define MANAGEMENT_ORB_PASSWORD_LENGTH(v)	((v) << 16)
 274
 275struct sbp2_management_orb {
 276	struct sbp2_orb base;
 277	struct {
 278		struct sbp2_pointer password;
 279		struct sbp2_pointer response;
 280		__be32 misc;
 281		__be32 length;
 282		struct sbp2_pointer status_fifo;
 283	} request;
 284	__be32 response[4];
 285	dma_addr_t response_bus;
 286	struct completion done;
 287	struct sbp2_status status;
 288};
 289
 290struct sbp2_login_response {
 291	__be32 misc;
 292	struct sbp2_pointer command_block_agent;
 293	__be32 reconnect_hold;
 294};
 295#define COMMAND_ORB_DATA_SIZE(v)	((v))
 296#define COMMAND_ORB_PAGE_SIZE(v)	((v) << 16)
 297#define COMMAND_ORB_PAGE_TABLE_PRESENT	((1) << 19)
 298#define COMMAND_ORB_MAX_PAYLOAD(v)	((v) << 20)
 299#define COMMAND_ORB_SPEED(v)		((v) << 24)
 300#define COMMAND_ORB_DIRECTION		((1) << 27)
 301#define COMMAND_ORB_REQUEST_FORMAT(v)	((v) << 29)
 302#define COMMAND_ORB_NOTIFY		((1) << 31)
 303
 304struct sbp2_command_orb {
 305	struct sbp2_orb base;
 306	struct {
 307		struct sbp2_pointer next;
 308		struct sbp2_pointer data_descriptor;
 309		__be32 misc;
 310		u8 command_block[SBP2_MAX_CDB_SIZE];
 311	} request;
 312	struct scsi_cmnd *cmd;
 313
 314	struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
 315	dma_addr_t page_table_bus;
 316};
 317
 318#define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
 319#define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
 320
 321/*
 322 * List of devices with known bugs.
 323 *
 324 * The firmware_revision field, masked with 0xffff00, is the best
 325 * indicator for the type of bridge chip of a device.  It yields a few
 326 * false positives but this did not break correctly behaving devices
 327 * so far.
 328 */
 329static const struct {
 330	u32 firmware_revision;
 331	u32 model;
 332	unsigned int workarounds;
 333} sbp2_workarounds_table[] = {
 334	/* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
 335		.firmware_revision	= 0x002800,
 336		.model			= 0x001010,
 337		.workarounds		= SBP2_WORKAROUND_INQUIRY_36 |
 338					  SBP2_WORKAROUND_MODE_SENSE_8 |
 339					  SBP2_WORKAROUND_POWER_CONDITION,
 340	},
 341	/* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
 342		.firmware_revision	= 0x002800,
 343		.model			= 0x000000,
 344		.workarounds		= SBP2_WORKAROUND_POWER_CONDITION,
 345	},
 346	/* Initio bridges, actually only needed for some older ones */ {
 347		.firmware_revision	= 0x000200,
 348		.model			= SBP2_ROM_VALUE_WILDCARD,
 349		.workarounds		= SBP2_WORKAROUND_INQUIRY_36,
 350	},
 351	/* PL-3507 bridge with Prolific firmware */ {
 352		.firmware_revision	= 0x012800,
 353		.model			= SBP2_ROM_VALUE_WILDCARD,
 354		.workarounds		= SBP2_WORKAROUND_POWER_CONDITION,
 355	},
 356	/* Symbios bridge */ {
 357		.firmware_revision	= 0xa0b800,
 358		.model			= SBP2_ROM_VALUE_WILDCARD,
 359		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS,
 360	},
 361	/* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
 362		.firmware_revision	= 0x002600,
 363		.model			= SBP2_ROM_VALUE_WILDCARD,
 364		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS,
 365	},
 366	/*
 367	 * iPod 2nd generation: needs 128k max transfer size workaround
 368	 * iPod 3rd generation: needs fix capacity workaround
 369	 */
 370	{
 371		.firmware_revision	= 0x0a2700,
 372		.model			= 0x000000,
 373		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS |
 374					  SBP2_WORKAROUND_FIX_CAPACITY,
 375	},
 376	/* iPod 4th generation */ {
 377		.firmware_revision	= 0x0a2700,
 378		.model			= 0x000021,
 379		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
 380	},
 381	/* iPod mini */ {
 382		.firmware_revision	= 0x0a2700,
 383		.model			= 0x000022,
 384		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
 385	},
 386	/* iPod mini */ {
 387		.firmware_revision	= 0x0a2700,
 388		.model			= 0x000023,
 389		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
 390	},
 391	/* iPod Photo */ {
 392		.firmware_revision	= 0x0a2700,
 393		.model			= 0x00007e,
 394		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
 395	}
 396};
 397
 398static void free_orb(struct kref *kref)
 399{
 400	struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
 401
 402	kfree(orb);
 403}
 404
 405static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
 406			      int tcode, int destination, int source,
 407			      int generation, unsigned long long offset,
 408			      void *payload, size_t length, void *callback_data)
 409{
 410	struct sbp2_logical_unit *lu = callback_data;
 411	struct sbp2_orb *orb = NULL, *iter;
 412	struct sbp2_status status;
 413	unsigned long flags;
 414
 415	if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
 416	    length < 8 || length > sizeof(status)) {
 417		fw_send_response(card, request, RCODE_TYPE_ERROR);
 418		return;
 419	}
 420
 421	status.status  = be32_to_cpup(payload);
 422	status.orb_low = be32_to_cpup(payload + 4);
 423	memset(status.data, 0, sizeof(status.data));
 424	if (length > 8)
 425		memcpy(status.data, payload + 8, length - 8);
 426
 427	if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
 428		dev_notice(lu_dev(lu),
 429			   "non-ORB related status write, not handled\n");
 430		fw_send_response(card, request, RCODE_COMPLETE);
 431		return;
 432	}
 433
 434	/* Lookup the orb corresponding to this status write. */
 435	spin_lock_irqsave(&lu->tgt->lock, flags);
 436	list_for_each_entry(iter, &lu->orb_list, link) {
 437		if (STATUS_GET_ORB_HIGH(status) == 0 &&
 438		    STATUS_GET_ORB_LOW(status) == iter->request_bus) {
 439			iter->rcode = RCODE_COMPLETE;
 440			list_del(&iter->link);
 441			orb = iter;
 442			break;
 443		}
 444	}
 445	spin_unlock_irqrestore(&lu->tgt->lock, flags);
 446
 447	if (orb) {
 448		orb->callback(orb, &status);
 449		kref_put(&orb->kref, free_orb); /* orb callback reference */
 450	} else {
 451		dev_err(lu_dev(lu), "status write for unknown ORB\n");
 452	}
 453
 454	fw_send_response(card, request, RCODE_COMPLETE);
 455}
 456
 457static void complete_transaction(struct fw_card *card, int rcode,
 458				 void *payload, size_t length, void *data)
 459{
 460	struct sbp2_orb *orb = data;
 461	unsigned long flags;
 462
 463	/*
 464	 * This is a little tricky.  We can get the status write for
 465	 * the orb before we get this callback.  The status write
 466	 * handler above will assume the orb pointer transaction was
 467	 * successful and set the rcode to RCODE_COMPLETE for the orb.
 468	 * So this callback only sets the rcode if it hasn't already
 469	 * been set and only does the cleanup if the transaction
 470	 * failed and we didn't already get a status write.
 471	 */
 472	spin_lock_irqsave(&orb->lu->tgt->lock, flags);
 473
 474	if (orb->rcode == -1)
 475		orb->rcode = rcode;
 476	if (orb->rcode != RCODE_COMPLETE) {
 477		list_del(&orb->link);
 478		spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 479
 480		orb->callback(orb, NULL);
 481		kref_put(&orb->kref, free_orb); /* orb callback reference */
 482	} else {
 483		spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
 484	}
 485
 486	kref_put(&orb->kref, free_orb); /* transaction callback reference */
 487}
 488
 489static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
 490			  int node_id, int generation, u64 offset)
 491{
 492	struct fw_device *device = target_parent_device(lu->tgt);
 493	struct sbp2_pointer orb_pointer;
 494	unsigned long flags;
 495
 496	orb_pointer.high = 0;
 497	orb_pointer.low = cpu_to_be32(orb->request_bus);
 498
 499	orb->lu = lu;
 500	spin_lock_irqsave(&lu->tgt->lock, flags);
 501	list_add_tail(&orb->link, &lu->orb_list);
 502	spin_unlock_irqrestore(&lu->tgt->lock, flags);
 503
 504	kref_get(&orb->kref); /* transaction callback reference */
 505	kref_get(&orb->kref); /* orb callback reference */
 506
 507	fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
 508			node_id, generation, device->max_speed, offset,
 509			&orb_pointer, 8, complete_transaction, orb);
 510}
 511
 512static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
 513{
 514	struct fw_device *device = target_parent_device(lu->tgt);
 515	struct sbp2_orb *orb, *next;
 516	struct list_head list;
 517	int retval = -ENOENT;
 518
 519	INIT_LIST_HEAD(&list);
 520	spin_lock_irq(&lu->tgt->lock);
 521	list_splice_init(&lu->orb_list, &list);
 522	spin_unlock_irq(&lu->tgt->lock);
 523
 524	list_for_each_entry_safe(orb, next, &list, link) {
 525		retval = 0;
 526		if (fw_cancel_transaction(device->card, &orb->t) == 0)
 527			continue;
 528
 529		orb->rcode = RCODE_CANCELLED;
 530		orb->callback(orb, NULL);
 531		kref_put(&orb->kref, free_orb); /* orb callback reference */
 532	}
 533
 534	return retval;
 535}
 536
 537static void complete_management_orb(struct sbp2_orb *base_orb,
 538				    struct sbp2_status *status)
 539{
 540	struct sbp2_management_orb *orb =
 541		container_of(base_orb, struct sbp2_management_orb, base);
 542
 543	if (status)
 544		memcpy(&orb->status, status, sizeof(*status));
 545	complete(&orb->done);
 546}
 547
 548static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 549				    int generation, int function,
 550				    int lun_or_login_id, void *response)
 551{
 552	struct fw_device *device = target_parent_device(lu->tgt);
 553	struct sbp2_management_orb *orb;
 554	unsigned int timeout;
 555	int retval = -ENOMEM;
 556
 557	if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
 558		return 0;
 559
 560	orb = kzalloc(sizeof(*orb), GFP_NOIO);
 561	if (orb == NULL)
 562		return -ENOMEM;
 563
 564	kref_init(&orb->base.kref);
 565	orb->response_bus =
 566		dma_map_single(device->card->device, &orb->response,
 567			       sizeof(orb->response), DMA_FROM_DEVICE);
 568	if (dma_mapping_error(device->card->device, orb->response_bus))
 569		goto fail_mapping_response;
 570
 571	orb->request.response.high = 0;
 572	orb->request.response.low  = cpu_to_be32(orb->response_bus);
 573
 574	orb->request.misc = cpu_to_be32(
 575		MANAGEMENT_ORB_NOTIFY |
 576		MANAGEMENT_ORB_FUNCTION(function) |
 577		MANAGEMENT_ORB_LUN(lun_or_login_id));
 578	orb->request.length = cpu_to_be32(
 579		MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
 580
 581	orb->request.status_fifo.high =
 582		cpu_to_be32(lu->address_handler.offset >> 32);
 583	orb->request.status_fifo.low  =
 584		cpu_to_be32(lu->address_handler.offset);
 585
 586	if (function == SBP2_LOGIN_REQUEST) {
 587		/* Ask for 2^2 == 4 seconds reconnect grace period */
 588		orb->request.misc |= cpu_to_be32(
 589			MANAGEMENT_ORB_RECONNECT(2) |
 590			MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
 591		timeout = lu->tgt->mgt_orb_timeout;
 592	} else {
 593		timeout = SBP2_ORB_TIMEOUT;
 594	}
 595
 596	init_completion(&orb->done);
 597	orb->base.callback = complete_management_orb;
 598
 599	orb->base.request_bus =
 600		dma_map_single(device->card->device, &orb->request,
 601			       sizeof(orb->request), DMA_TO_DEVICE);
 602	if (dma_mapping_error(device->card->device, orb->base.request_bus))
 603		goto fail_mapping_request;
 604
 605	sbp2_send_orb(&orb->base, lu, node_id, generation,
 606		      lu->tgt->management_agent_address);
 607
 608	wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
 609
 610	retval = -EIO;
 611	if (sbp2_cancel_orbs(lu) == 0) {
 612		dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
 613			orb->base.rcode);
 614		goto out;
 615	}
 616
 617	if (orb->base.rcode != RCODE_COMPLETE) {
 618		dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
 619			orb->base.rcode);
 620		goto out;
 621	}
 622
 623	if (STATUS_GET_RESPONSE(orb->status) != 0 ||
 624	    STATUS_GET_SBP_STATUS(orb->status) != 0) {
 625		dev_err(lu_dev(lu), "error status: %d:%d\n",
 626			 STATUS_GET_RESPONSE(orb->status),
 627			 STATUS_GET_SBP_STATUS(orb->status));
 628		goto out;
 629	}
 630
 631	retval = 0;
 632 out:
 633	dma_unmap_single(device->card->device, orb->base.request_bus,
 634			 sizeof(orb->request), DMA_TO_DEVICE);
 635 fail_mapping_request:
 636	dma_unmap_single(device->card->device, orb->response_bus,
 637			 sizeof(orb->response), DMA_FROM_DEVICE);
 638 fail_mapping_response:
 639	if (response)
 640		memcpy(response, orb->response, sizeof(orb->response));
 641	kref_put(&orb->base.kref, free_orb);
 642
 643	return retval;
 644}
 645
 646static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 647{
 648	struct fw_device *device = target_parent_device(lu->tgt);
 649	__be32 d = 0;
 650
 651	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 652			   lu->tgt->node_id, lu->generation, device->max_speed,
 653			   lu->command_block_agent_address + SBP2_AGENT_RESET,
 654			   &d, 4);
 655}
 656
 657static void complete_agent_reset_write_no_wait(struct fw_card *card,
 658		int rcode, void *payload, size_t length, void *data)
 659{
 660	kfree(data);
 661}
 662
 663static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 664{
 665	struct fw_device *device = target_parent_device(lu->tgt);
 666	struct fw_transaction *t;
 667	static __be32 d;
 668
 669	t = kmalloc(sizeof(*t), GFP_ATOMIC);
 670	if (t == NULL)
 671		return;
 672
 673	fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 674			lu->tgt->node_id, lu->generation, device->max_speed,
 675			lu->command_block_agent_address + SBP2_AGENT_RESET,
 676			&d, 4, complete_agent_reset_write_no_wait, t);
 677}
 678
 679static inline void sbp2_allow_block(struct sbp2_target *tgt)
 680{
 681	spin_lock_irq(&tgt->lock);
 682	--tgt->dont_block;
 683	spin_unlock_irq(&tgt->lock);
 684}
 685
 686/*
 687 * Blocks lu->tgt if all of the following conditions are met:
 688 *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
 689 *     logical units have been finished (indicated by dont_block == 0).
 690 *   - lu->generation is stale.
 691 *
 692 * Note, scsi_block_requests() must be called while holding tgt->lock,
 693 * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
 694 * unblock the target.
 695 */
 696static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
 697{
 698	struct sbp2_target *tgt = lu->tgt;
 699	struct fw_card *card = target_parent_device(tgt)->card;
 700	struct Scsi_Host *shost =
 701		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 702	unsigned long flags;
 703
 704	spin_lock_irqsave(&tgt->lock, flags);
 705	if (!tgt->dont_block && !lu->blocked &&
 706	    lu->generation != card->generation) {
 707		lu->blocked = true;
 708		if (++tgt->blocked == 1)
 709			scsi_block_requests(shost);
 710	}
 711	spin_unlock_irqrestore(&tgt->lock, flags);
 712}
 713
 714/*
 715 * Unblocks lu->tgt as soon as all its logical units can be unblocked.
 716 * Note, it is harmless to run scsi_unblock_requests() outside the
 717 * tgt->lock protected section.  On the other hand, running it inside
 718 * the section might clash with shost->host_lock.
 719 */
 720static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
 721{
 722	struct sbp2_target *tgt = lu->tgt;
 723	struct fw_card *card = target_parent_device(tgt)->card;
 724	struct Scsi_Host *shost =
 725		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 726	bool unblock = false;
 727
 728	spin_lock_irq(&tgt->lock);
 729	if (lu->blocked && lu->generation == card->generation) {
 730		lu->blocked = false;
 731		unblock = --tgt->blocked == 0;
 732	}
 733	spin_unlock_irq(&tgt->lock);
 734
 735	if (unblock)
 736		scsi_unblock_requests(shost);
 737}
 738
 739/*
 740 * Prevents future blocking of tgt and unblocks it.
 741 * Note, it is harmless to run scsi_unblock_requests() outside the
 742 * tgt->lock protected section.  On the other hand, running it inside
 743 * the section might clash with shost->host_lock.
 744 */
 745static void sbp2_unblock(struct sbp2_target *tgt)
 746{
 747	struct Scsi_Host *shost =
 748		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 749
 750	spin_lock_irq(&tgt->lock);
 751	++tgt->dont_block;
 752	spin_unlock_irq(&tgt->lock);
 753
 754	scsi_unblock_requests(shost);
 755}
 756
 757static int sbp2_lun2int(u16 lun)
 758{
 759	struct scsi_lun eight_bytes_lun;
 760
 761	memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
 762	eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
 763	eight_bytes_lun.scsi_lun[1] = lun & 0xff;
 764
 765	return scsilun_to_int(&eight_bytes_lun);
 766}
 767
 768/*
 769 * Write retransmit retry values into the BUSY_TIMEOUT register.
 770 * - The single-phase retry protocol is supported by all SBP-2 devices, but the
 771 *   default retry_limit value is 0 (i.e. never retry transmission). We write a
 772 *   saner value after logging into the device.
 773 * - The dual-phase retry protocol is optional to implement, and if not
 774 *   supported, writes to the dual-phase portion of the register will be
 775 *   ignored. We try to write the original 1394-1995 default here.
 776 * - In the case of devices that are also SBP-3-compliant, all writes are
 777 *   ignored, as the register is read-only, but contains single-phase retry of
 778 *   15, which is what we're trying to set for all SBP-2 device anyway, so this
 779 *   write attempt is safe and yields more consistent behavior for all devices.
 780 *
 781 * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
 782 * and section 6.4 of the SBP-3 spec for further details.
 783 */
 784static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 785{
 786	struct fw_device *device = target_parent_device(lu->tgt);
 787	__be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 788
 789	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
 790			   lu->tgt->node_id, lu->generation, device->max_speed,
 791			   CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
 792}
 793
 794static void sbp2_reconnect(struct work_struct *work);
 795
 796static void sbp2_login(struct work_struct *work)
 797{
 798	struct sbp2_logical_unit *lu =
 799		container_of(work, struct sbp2_logical_unit, work.work);
 800	struct sbp2_target *tgt = lu->tgt;
 801	struct fw_device *device = target_parent_device(tgt);
 802	struct Scsi_Host *shost;
 803	struct scsi_device *sdev;
 804	struct sbp2_login_response response;
 805	int generation, node_id, local_node_id;
 806
 807	if (fw_device_is_shutdown(device))
 808		return;
 809
 810	generation    = device->generation;
 811	smp_rmb();    /* node IDs must not be older than generation */
 812	node_id       = device->node_id;
 813	local_node_id = device->card->node_id;
 814
 815	/* If this is a re-login attempt, log out, or we might be rejected. */
 816	if (lu->has_sdev)
 817		sbp2_send_management_orb(lu, device->node_id, generation,
 818				SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 819
 820	if (sbp2_send_management_orb(lu, node_id, generation,
 821				SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
 822		if (lu->retries++ < 5) {
 823			sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 824		} else {
 825			dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
 826				lu->lun);
 827			/* Let any waiting I/O fail from now on. */
 828			sbp2_unblock(lu->tgt);
 829		}
 830		return;
 831	}
 832
 833	tgt->node_id	  = node_id;
 834	tgt->address_high = local_node_id << 16;
 835	smp_wmb();	  /* node IDs must not be older than generation */
 836	lu->generation	  = generation;
 837
 838	lu->command_block_agent_address =
 839		((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
 840		      << 32) | be32_to_cpu(response.command_block_agent.low);
 841	lu->login_id = be32_to_cpu(response.misc) & 0xffff;
 842
 843	dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
 844		   lu->lun, lu->retries);
 845
 846	/* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 847	sbp2_set_busy_timeout(lu);
 848
 849	lu->workfn = sbp2_reconnect;
 850	sbp2_agent_reset(lu);
 851
 852	/* This was a re-login. */
 853	if (lu->has_sdev) {
 854		sbp2_cancel_orbs(lu);
 855		sbp2_conditionally_unblock(lu);
 856
 857		return;
 858	}
 859
 860	if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
 861		ssleep(SBP2_INQUIRY_DELAY);
 862
 863	shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
 864	sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
 865	/*
 866	 * FIXME:  We are unable to perform reconnects while in sbp2_login().
 867	 * Therefore __scsi_add_device() will get into trouble if a bus reset
 868	 * happens in parallel.  It will either fail or leave us with an
 869	 * unusable sdev.  As a workaround we check for this and retry the
 870	 * whole login and SCSI probing.
 871	 */
 872
 873	/* Reported error during __scsi_add_device() */
 874	if (IS_ERR(sdev))
 875		goto out_logout_login;
 876
 877	/* Unreported error during __scsi_add_device() */
 878	smp_rmb(); /* get current card generation */
 879	if (generation != device->card->generation) {
 880		scsi_remove_device(sdev);
 881		scsi_device_put(sdev);
 882		goto out_logout_login;
 883	}
 884
 885	/* No error during __scsi_add_device() */
 886	lu->has_sdev = true;
 887	scsi_device_put(sdev);
 888	sbp2_allow_block(tgt);
 889
 890	return;
 891
 892 out_logout_login:
 893	smp_rmb(); /* generation may have changed */
 894	generation = device->generation;
 895	smp_rmb(); /* node_id must not be older than generation */
 896
 897	sbp2_send_management_orb(lu, device->node_id, generation,
 898				 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
 899	/*
 900	 * If a bus reset happened, sbp2_update will have requeued
 901	 * lu->work already.  Reset the work from reconnect to login.
 902	 */
 903	lu->workfn = sbp2_login;
 904}
 905
 906static void sbp2_reconnect(struct work_struct *work)
 907{
 908	struct sbp2_logical_unit *lu =
 909		container_of(work, struct sbp2_logical_unit, work.work);
 910	struct sbp2_target *tgt = lu->tgt;
 911	struct fw_device *device = target_parent_device(tgt);
 912	int generation, node_id, local_node_id;
 913
 914	if (fw_device_is_shutdown(device))
 915		return;
 916
 917	generation    = device->generation;
 918	smp_rmb();    /* node IDs must not be older than generation */
 919	node_id       = device->node_id;
 920	local_node_id = device->card->node_id;
 921
 922	if (sbp2_send_management_orb(lu, node_id, generation,
 923				     SBP2_RECONNECT_REQUEST,
 924				     lu->login_id, NULL) < 0) {
 925		/*
 926		 * If reconnect was impossible even though we are in the
 927		 * current generation, fall back and try to log in again.
 928		 *
 929		 * We could check for "Function rejected" status, but
 930		 * looking at the bus generation as simpler and more general.
 931		 */
 932		smp_rmb(); /* get current card generation */
 933		if (generation == device->card->generation ||
 934		    lu->retries++ >= 5) {
 935			dev_err(tgt_dev(tgt), "failed to reconnect\n");
 936			lu->retries = 0;
 937			lu->workfn = sbp2_login;
 938		}
 939		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 940
 941		return;
 942	}
 943
 944	tgt->node_id      = node_id;
 945	tgt->address_high = local_node_id << 16;
 946	smp_wmb();	  /* node IDs must not be older than generation */
 947	lu->generation	  = generation;
 948
 949	dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
 950		   lu->lun, lu->retries);
 951
 952	sbp2_agent_reset(lu);
 953	sbp2_cancel_orbs(lu);
 954	sbp2_conditionally_unblock(lu);
 955}
 956
 957static void sbp2_lu_workfn(struct work_struct *work)
 958{
 959	struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
 960						struct sbp2_logical_unit, work);
 961	lu->workfn(work);
 962}
 963
 964static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 965{
 966	struct sbp2_logical_unit *lu;
 967
 968	lu = kmalloc(sizeof(*lu), GFP_KERNEL);
 969	if (!lu)
 970		return -ENOMEM;
 971
 972	lu->address_handler.length           = 0x100;
 973	lu->address_handler.address_callback = sbp2_status_write;
 974	lu->address_handler.callback_data    = lu;
 975
 976	if (fw_core_add_address_handler(&lu->address_handler,
 977					&fw_high_memory_region) < 0) {
 978		kfree(lu);
 979		return -ENOMEM;
 980	}
 981
 982	lu->tgt      = tgt;
 983	lu->lun      = lun_entry & 0xffff;
 984	lu->login_id = INVALID_LOGIN_ID;
 985	lu->retries  = 0;
 986	lu->has_sdev = false;
 987	lu->blocked  = false;
 988	++tgt->dont_block;
 989	INIT_LIST_HEAD(&lu->orb_list);
 990	lu->workfn = sbp2_login;
 991	INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
 992
 993	list_add_tail(&lu->link, &tgt->lu_list);
 994	return 0;
 995}
 996
 997static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
 998				    const u32 *leaf)
 999{
1000	if ((leaf[0] & 0xffff0000) == 0x00020000)
1001		tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1002}
1003
1004static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1005				      const u32 *directory)
1006{
1007	struct fw_csr_iterator ci;
1008	int key, value;
1009
1010	fw_csr_iterator_init(&ci, directory);
1011	while (fw_csr_iterator_next(&ci, &key, &value))
1012		if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1013		    sbp2_add_logical_unit(tgt, value) < 0)
1014			return -ENOMEM;
1015	return 0;
1016}
1017
1018static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1019			      u32 *model, u32 *firmware_revision)
1020{
1021	struct fw_csr_iterator ci;
1022	int key, value;
1023
1024	fw_csr_iterator_init(&ci, directory);
1025	while (fw_csr_iterator_next(&ci, &key, &value)) {
1026		switch (key) {
1027
1028		case CSR_DEPENDENT_INFO | CSR_OFFSET:
1029			tgt->management_agent_address =
1030					CSR_REGISTER_BASE + 4 * value;
1031			break;
1032
1033		case CSR_DIRECTORY_ID:
1034			tgt->directory_id = value;
1035			break;
1036
1037		case CSR_MODEL:
1038			*model = value;
1039			break;
1040
1041		case SBP2_CSR_FIRMWARE_REVISION:
1042			*firmware_revision = value;
1043			break;
1044
1045		case SBP2_CSR_UNIT_CHARACTERISTICS:
1046			/* the timeout value is stored in 500ms units */
1047			tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1048			break;
1049
1050		case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1051			if (sbp2_add_logical_unit(tgt, value) < 0)
1052				return -ENOMEM;
1053			break;
1054
1055		case SBP2_CSR_UNIT_UNIQUE_ID:
1056			sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1057			break;
1058
1059		case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1060			/* Adjust for the increment in the iterator */
1061			if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1062				return -ENOMEM;
1063			break;
1064		}
1065	}
1066	return 0;
1067}
1068
1069/*
1070 * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1071 * provided in the config rom. Most devices do provide a value, which
1072 * we'll use for login management orbs, but with some sane limits.
1073 */
1074static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1075{
1076	unsigned int timeout = tgt->mgt_orb_timeout;
1077
1078	if (timeout > 40000)
1079		dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1080			   timeout / 1000);
1081
1082	tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1083}
1084
1085static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1086				  u32 firmware_revision)
1087{
1088	int i;
1089	unsigned int w = sbp2_param_workarounds;
1090
1091	if (w)
1092		dev_notice(tgt_dev(tgt),
1093			   "Please notify linux1394-devel@lists.sf.net "
1094			   "if you need the workarounds parameter\n");
1095
1096	if (w & SBP2_WORKAROUND_OVERRIDE)
1097		goto out;
1098
1099	for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1100
1101		if (sbp2_workarounds_table[i].firmware_revision !=
1102		    (firmware_revision & 0xffffff00))
1103			continue;
1104
1105		if (sbp2_workarounds_table[i].model != model &&
1106		    sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1107			continue;
1108
1109		w |= sbp2_workarounds_table[i].workarounds;
1110		break;
1111	}
1112 out:
1113	if (w)
1114		dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1115			   "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1116			   w, firmware_revision, model);
1117	tgt->workarounds = w;
1118}
1119
1120static struct scsi_host_template scsi_driver_template;
1121static void sbp2_remove(struct fw_unit *unit);
1122
1123static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1124{
1125	struct fw_device *device = fw_parent_device(unit);
1126	struct sbp2_target *tgt;
1127	struct sbp2_logical_unit *lu;
1128	struct Scsi_Host *shost;
1129	u32 model, firmware_revision;
1130
1131	/* cannot (or should not) handle targets on the local node */
1132	if (device->is_local)
1133		return -ENODEV;
1134
1135	shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1136	if (shost == NULL)
1137		return -ENOMEM;
1138
1139	tgt = (struct sbp2_target *)shost->hostdata;
1140	dev_set_drvdata(&unit->device, tgt);
1141	tgt->unit = unit;
1142	INIT_LIST_HEAD(&tgt->lu_list);
1143	spin_lock_init(&tgt->lock);
1144	tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1145
1146	if (fw_device_enable_phys_dma(device) < 0)
1147		goto fail_shost_put;
1148
1149	shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1150
1151	if (scsi_add_host_with_dma(shost, &unit->device,
1152				   device->card->device) < 0)
1153		goto fail_shost_put;
1154
1155	/* implicit directory ID */
1156	tgt->directory_id = ((unit->directory - device->config_rom) * 4
1157			     + CSR_CONFIG_ROM) & 0xffffff;
1158
1159	firmware_revision = SBP2_ROM_VALUE_MISSING;
1160	model		  = SBP2_ROM_VALUE_MISSING;
1161
1162	if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1163			       &firmware_revision) < 0)
1164		goto fail_remove;
1165
1166	sbp2_clamp_management_orb_timeout(tgt);
1167	sbp2_init_workarounds(tgt, model, firmware_revision);
1168
1169	/*
1170	 * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1171	 * and so on up to 4096 bytes.  The SBP-2 max_payload field
1172	 * specifies the max payload size as 2 ^ (max_payload + 2), so
1173	 * if we set this to max_speed + 7, we get the right value.
1174	 */
1175	tgt->max_payload = min3(device->max_speed + 7, 10U,
1176				device->card->max_receive - 1);
1177
1178	/* Do the login in a workqueue so we can easily reschedule retries. */
1179	list_for_each_entry(lu, &tgt->lu_list, link)
1180		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1181
1182	return 0;
1183
1184 fail_remove:
1185	sbp2_remove(unit);
1186	return -ENOMEM;
1187
1188 fail_shost_put:
1189	scsi_host_put(shost);
1190	return -ENOMEM;
1191}
1192
1193static void sbp2_update(struct fw_unit *unit)
1194{
1195	struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1196	struct sbp2_logical_unit *lu;
1197
1198	fw_device_enable_phys_dma(fw_parent_device(unit));
1199
1200	/*
1201	 * Fw-core serializes sbp2_update() against sbp2_remove().
1202	 * Iteration over tgt->lu_list is therefore safe here.
1203	 */
1204	list_for_each_entry(lu, &tgt->lu_list, link) {
1205		sbp2_conditionally_block(lu);
1206		lu->retries = 0;
1207		sbp2_queue_work(lu, 0);
1208	}
1209}
1210
1211static void sbp2_remove(struct fw_unit *unit)
1212{
1213	struct fw_device *device = fw_parent_device(unit);
1214	struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1215	struct sbp2_logical_unit *lu, *next;
1216	struct Scsi_Host *shost =
1217		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1218	struct scsi_device *sdev;
1219
1220	/* prevent deadlocks */
1221	sbp2_unblock(tgt);
1222
1223	list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1224		cancel_delayed_work_sync(&lu->work);
1225		sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1226		if (sdev) {
1227			scsi_remove_device(sdev);
1228			scsi_device_put(sdev);
1229		}
1230		if (lu->login_id != INVALID_LOGIN_ID) {
1231			int generation, node_id;
1232			/*
1233			 * tgt->node_id may be obsolete here if we failed
1234			 * during initial login or after a bus reset where
1235			 * the topology changed.
1236			 */
1237			generation = device->generation;
1238			smp_rmb(); /* node_id vs. generation */
1239			node_id    = device->node_id;
1240			sbp2_send_management_orb(lu, node_id, generation,
1241						 SBP2_LOGOUT_REQUEST,
1242						 lu->login_id, NULL);
1243		}
1244		fw_core_remove_address_handler(&lu->address_handler);
1245		list_del(&lu->link);
1246		kfree(lu);
1247	}
1248	scsi_remove_host(shost);
1249	dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1250
1251	scsi_host_put(shost);
1252}
1253
1254#define SBP2_UNIT_SPEC_ID_ENTRY	0x0000609e
1255#define SBP2_SW_VERSION_ENTRY	0x00010483
1256
1257static const struct ieee1394_device_id sbp2_id_table[] = {
1258	{
1259		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1260				IEEE1394_MATCH_VERSION,
1261		.specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1262		.version      = SBP2_SW_VERSION_ENTRY,
1263	},
1264	{ }
1265};
1266
1267static struct fw_driver sbp2_driver = {
1268	.driver   = {
1269		.owner  = THIS_MODULE,
1270		.name   = KBUILD_MODNAME,
1271		.bus    = &fw_bus_type,
1272	},
1273	.probe    = sbp2_probe,
1274	.update   = sbp2_update,
1275	.remove   = sbp2_remove,
1276	.id_table = sbp2_id_table,
1277};
1278
1279static void sbp2_unmap_scatterlist(struct device *card_device,
1280				   struct sbp2_command_orb *orb)
1281{
1282	scsi_dma_unmap(orb->cmd);
1283
1284	if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1285		dma_unmap_single(card_device, orb->page_table_bus,
1286				 sizeof(orb->page_table), DMA_TO_DEVICE);
1287}
1288
1289static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1290{
1291	int sam_status;
1292	int sfmt = (sbp2_status[0] >> 6) & 0x03;
1293
1294	if (sfmt == 2 || sfmt == 3) {
1295		/*
1296		 * Reserved for future standardization (2) or
1297		 * Status block format vendor-dependent (3)
1298		 */
1299		return DID_ERROR << 16;
1300	}
1301
1302	sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1303	sense_data[1] = 0x0;
1304	sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1305	sense_data[3] = sbp2_status[4];
1306	sense_data[4] = sbp2_status[5];
1307	sense_data[5] = sbp2_status[6];
1308	sense_data[6] = sbp2_status[7];
1309	sense_data[7] = 10;
1310	sense_data[8] = sbp2_status[8];
1311	sense_data[9] = sbp2_status[9];
1312	sense_data[10] = sbp2_status[10];
1313	sense_data[11] = sbp2_status[11];
1314	sense_data[12] = sbp2_status[2];
1315	sense_data[13] = sbp2_status[3];
1316	sense_data[14] = sbp2_status[12];
1317	sense_data[15] = sbp2_status[13];
1318
1319	sam_status = sbp2_status[0] & 0x3f;
1320
1321	switch (sam_status) {
1322	case SAM_STAT_GOOD:
1323	case SAM_STAT_CHECK_CONDITION:
1324	case SAM_STAT_CONDITION_MET:
1325	case SAM_STAT_BUSY:
1326	case SAM_STAT_RESERVATION_CONFLICT:
1327	case SAM_STAT_COMMAND_TERMINATED:
1328		return DID_OK << 16 | sam_status;
1329
1330	default:
1331		return DID_ERROR << 16;
1332	}
1333}
1334
1335static void complete_command_orb(struct sbp2_orb *base_orb,
1336				 struct sbp2_status *status)
1337{
1338	struct sbp2_command_orb *orb =
1339		container_of(base_orb, struct sbp2_command_orb, base);
1340	struct fw_device *device = target_parent_device(base_orb->lu->tgt);
1341	int result;
1342
1343	if (status != NULL) {
1344		if (STATUS_GET_DEAD(*status))
1345			sbp2_agent_reset_no_wait(base_orb->lu);
1346
1347		switch (STATUS_GET_RESPONSE(*status)) {
1348		case SBP2_STATUS_REQUEST_COMPLETE:
1349			result = DID_OK << 16;
1350			break;
1351		case SBP2_STATUS_TRANSPORT_FAILURE:
1352			result = DID_BUS_BUSY << 16;
1353			break;
1354		case SBP2_STATUS_ILLEGAL_REQUEST:
1355		case SBP2_STATUS_VENDOR_DEPENDENT:
1356		default:
1357			result = DID_ERROR << 16;
1358			break;
1359		}
1360
1361		if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1362			result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1363							   orb->cmd->sense_buffer);
1364	} else {
1365		/*
1366		 * If the orb completes with status == NULL, something
1367		 * went wrong, typically a bus reset happened mid-orb
1368		 * or when sending the write (less likely).
1369		 */
1370		result = DID_BUS_BUSY << 16;
1371		sbp2_conditionally_block(base_orb->lu);
1372	}
1373
1374	dma_unmap_single(device->card->device, orb->base.request_bus,
1375			 sizeof(orb->request), DMA_TO_DEVICE);
1376	sbp2_unmap_scatterlist(device->card->device, orb);
1377
1378	orb->cmd->result = result;
1379	scsi_done(orb->cmd);
1380}
1381
1382static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1383		struct fw_device *device, struct sbp2_logical_unit *lu)
1384{
1385	struct scatterlist *sg = scsi_sglist(orb->cmd);
1386	int i, n;
1387
1388	n = scsi_dma_map(orb->cmd);
1389	if (n <= 0)
1390		goto fail;
1391
1392	/*
1393	 * Handle the special case where there is only one element in
1394	 * the scatter list by converting it to an immediate block
1395	 * request. This is also a workaround for broken devices such
1396	 * as the second generation iPod which doesn't support page
1397	 * tables.
1398	 */
1399	if (n == 1) {
1400		orb->request.data_descriptor.high =
1401			cpu_to_be32(lu->tgt->address_high);
1402		orb->request.data_descriptor.low  =
1403			cpu_to_be32(sg_dma_address(sg));
1404		orb->request.misc |=
1405			cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1406		return 0;
1407	}
1408
1409	for_each_sg(sg, sg, n, i) {
1410		orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1411		orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1412	}
1413
1414	orb->page_table_bus =
1415		dma_map_single(device->card->device, orb->page_table,
1416			       sizeof(orb->page_table), DMA_TO_DEVICE);
1417	if (dma_mapping_error(device->card->device, orb->page_table_bus))
1418		goto fail_page_table;
1419
1420	/*
1421	 * The data_descriptor pointer is the one case where we need
1422	 * to fill in the node ID part of the address.  All other
1423	 * pointers assume that the data referenced reside on the
1424	 * initiator (i.e. us), but data_descriptor can refer to data
1425	 * on other nodes so we need to put our ID in descriptor.high.
1426	 */
1427	orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1428	orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1429	orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1430					 COMMAND_ORB_DATA_SIZE(n));
1431
1432	return 0;
1433
1434 fail_page_table:
1435	scsi_dma_unmap(orb->cmd);
1436 fail:
1437	return -ENOMEM;
1438}
1439
1440/* SCSI stack integration */
1441
1442static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1443				  struct scsi_cmnd *cmd)
1444{
1445	struct sbp2_logical_unit *lu = cmd->device->hostdata;
1446	struct fw_device *device = target_parent_device(lu->tgt);
1447	struct sbp2_command_orb *orb;
1448	int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1449
1450	orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1451	if (orb == NULL)
1452		return SCSI_MLQUEUE_HOST_BUSY;
1453
1454	/* Initialize rcode to something not RCODE_COMPLETE. */
1455	orb->base.rcode = -1;
1456	kref_init(&orb->base.kref);
1457	orb->cmd = cmd;
1458	orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1459	orb->request.misc = cpu_to_be32(
1460		COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1461		COMMAND_ORB_SPEED(device->max_speed) |
1462		COMMAND_ORB_NOTIFY);
1463
1464	if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1465		orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1466
1467	generation = device->generation;
1468	smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1469
1470	if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1471		goto out;
1472
1473	memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1474
1475	orb->base.callback = complete_command_orb;
1476	orb->base.request_bus =
1477		dma_map_single(device->card->device, &orb->request,
1478			       sizeof(orb->request), DMA_TO_DEVICE);
1479	if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1480		sbp2_unmap_scatterlist(device->card->device, orb);
1481		goto out;
1482	}
1483
1484	sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1485		      lu->command_block_agent_address + SBP2_ORB_POINTER);
1486	retval = 0;
1487 out:
1488	kref_put(&orb->base.kref, free_orb);
1489	return retval;
1490}
1491
1492static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1493{
1494	struct sbp2_logical_unit *lu = sdev->hostdata;
1495
1496	/* (Re-)Adding logical units via the SCSI stack is not supported. */
1497	if (!lu)
1498		return -ENOSYS;
1499
1500	sdev->allow_restart = 1;
1501
1502	/*
1503	 * SBP-2 does not require any alignment, but we set it anyway
1504	 * for compatibility with earlier versions of this driver.
1505	 */
1506	blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1507
1508	if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1509		sdev->inquiry_len = 36;
1510
1511	return 0;
1512}
1513
1514static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1515{
1516	struct sbp2_logical_unit *lu = sdev->hostdata;
1517
1518	sdev->use_10_for_rw = 1;
1519
1520	if (sbp2_param_exclusive_login)
1521		sdev->manage_start_stop = 1;
1522
1523	if (sdev->type == TYPE_ROM)
1524		sdev->use_10_for_ms = 1;
1525
1526	if (sdev->type == TYPE_DISK &&
1527	    lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1528		sdev->skip_ms_page_8 = 1;
1529
1530	if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1531		sdev->fix_capacity = 1;
1532
1533	if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1534		sdev->start_stop_pwr_cond = 1;
1535
1536	if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1537		blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1538
1539	return 0;
1540}
1541
1542/*
1543 * Called by scsi stack when something has really gone wrong.  Usually
1544 * called when a command has timed-out for some reason.
1545 */
1546static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1547{
1548	struct sbp2_logical_unit *lu = cmd->device->hostdata;
1549
1550	dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1551	sbp2_agent_reset(lu);
1552	sbp2_cancel_orbs(lu);
1553
1554	return SUCCESS;
1555}
1556
1557/*
1558 * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1559 * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1560 *
1561 * This is the concatenation of target port identifier and logical unit
1562 * identifier as per SAM-2...SAM-4 annex A.
1563 */
1564static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1565			struct device_attribute *attr, char *buf)
1566{
1567	struct scsi_device *sdev = to_scsi_device(dev);
1568	struct sbp2_logical_unit *lu;
1569
1570	if (!sdev)
1571		return 0;
1572
1573	lu = sdev->hostdata;
1574
1575	return sprintf(buf, "%016llx:%06x:%04x\n",
1576			(unsigned long long)lu->tgt->guid,
1577			lu->tgt->directory_id, lu->lun);
1578}
1579
1580static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1581
1582static struct attribute *sbp2_scsi_sysfs_attrs[] = {
1583	&dev_attr_ieee1394_id.attr,
1584	NULL
1585};
1586
1587ATTRIBUTE_GROUPS(sbp2_scsi_sysfs);
1588
1589static struct scsi_host_template scsi_driver_template = {
1590	.module			= THIS_MODULE,
1591	.name			= "SBP-2 IEEE-1394",
1592	.proc_name		= "sbp2",
1593	.queuecommand		= sbp2_scsi_queuecommand,
1594	.slave_alloc		= sbp2_scsi_slave_alloc,
1595	.slave_configure	= sbp2_scsi_slave_configure,
1596	.eh_abort_handler	= sbp2_scsi_abort,
1597	.this_id		= -1,
1598	.sg_tablesize		= SG_ALL,
1599	.max_segment_size	= SBP2_MAX_SEG_SIZE,
1600	.can_queue		= 1,
1601	.sdev_groups		= sbp2_scsi_sysfs_groups,
1602};
1603
1604MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1605MODULE_DESCRIPTION("SCSI over IEEE1394");
1606MODULE_LICENSE("GPL");
1607MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1608
1609/* Provide a module alias so root-on-sbp2 initrds don't break. */
1610MODULE_ALIAS("sbp2");
1611
1612static int __init sbp2_init(void)
1613{
1614	return driver_register(&sbp2_driver.driver);
1615}
1616
1617static void __exit sbp2_cleanup(void)
1618{
1619	driver_unregister(&sbp2_driver.driver);
1620}
1621
1622module_init(sbp2_init);
1623module_exit(sbp2_cleanup);