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_system_start_stop or
85 *   manage_runtime_start_stop is on).
86 *   Some disks need this to spin down or to resume properly.
87 *
88 * - override internal blacklist
89 *   Instead of adding to the built-in blacklist, use only the workarounds
90 *   specified in the module load parameter.
91 *   Useful if a blacklist entry interfered with a non-broken device.
92 */
93#define SBP2_WORKAROUND_128K_MAX_TRANS	0x1
94#define SBP2_WORKAROUND_INQUIRY_36	0x2
95#define SBP2_WORKAROUND_MODE_SENSE_8	0x4
96#define SBP2_WORKAROUND_FIX_CAPACITY	0x8
97#define SBP2_WORKAROUND_DELAY_INQUIRY	0x10
98#define SBP2_INQUIRY_DELAY		12
99#define SBP2_WORKAROUND_POWER_CONDITION	0x20
100#define SBP2_WORKAROUND_OVERRIDE	0x100
101
102static int sbp2_param_workarounds;
103module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
104MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
105	", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
106	", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
107	", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
108	", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
109	", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
110	", set power condition in start stop unit = "
111				  __stringify(SBP2_WORKAROUND_POWER_CONDITION)
112	", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
113	", or a combination)");
114
115/*
116 * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
117 * and one struct scsi_device per sbp2_logical_unit.
118 */
119struct sbp2_logical_unit {
120	struct sbp2_target *tgt;
121	struct list_head link;
122	struct fw_address_handler address_handler;
123	struct list_head orb_list;
124
125	u64 command_block_agent_address;
126	u16 lun;
127	int login_id;
128
129	/*
130	 * The generation is updated once we've logged in or reconnected
131	 * to the logical unit.  Thus, I/O to the device will automatically
132	 * fail and get retried if it happens in a window where the device
133	 * is not ready, e.g. after a bus reset but before we reconnect.
134	 */
135	int generation;
136	int retries;
137	work_func_t workfn;
138	struct delayed_work work;
139	bool has_sdev;
140	bool blocked;
141};
142
143static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
144{
145	queue_delayed_work(fw_workqueue, &lu->work, delay);
146}
147
148/*
149 * We create one struct sbp2_target per IEEE 1212 Unit Directory
150 * and one struct Scsi_Host per sbp2_target.
151 */
152struct sbp2_target {
153	struct fw_unit *unit;
154	struct list_head lu_list;
155
156	u64 management_agent_address;
157	u64 guid;
158	int directory_id;
159	int node_id;
160	int address_high;
161	unsigned int workarounds;
162	unsigned int mgt_orb_timeout;
163	unsigned int max_payload;
164
165	spinlock_t lock;
166	int dont_block;	/* counter for each logical unit */
167	int blocked;	/* ditto */
168};
169
170static struct fw_device *target_parent_device(struct sbp2_target *tgt)
171{
172	return fw_parent_device(tgt->unit);
173}
174
175static const struct device *tgt_dev(const struct sbp2_target *tgt)
176{
177	return &tgt->unit->device;
178}
179
180static const struct device *lu_dev(const struct sbp2_logical_unit *lu)
181{
182	return &lu->tgt->unit->device;
183}
184
185/* Impossible login_id, to detect logout attempt before successful login */
186#define INVALID_LOGIN_ID 0x10000
187
188#define SBP2_ORB_TIMEOUT		2000U		/* Timeout in ms */
189#define SBP2_ORB_NULL			0x80000000
190#define SBP2_RETRY_LIMIT		0xf		/* 15 retries */
191#define SBP2_CYCLE_LIMIT		(0xc8 << 12)	/* 200 125us cycles */
192
193/*
194 * There is no transport protocol limit to the CDB length,  but we implement
195 * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
196 */
197#define SBP2_MAX_CDB_SIZE		16
198
199/*
200 * The maximum SBP-2 data buffer size is 0xffff.  We quadlet-align this
201 * for compatibility with earlier versions of this driver.
202 */
203#define SBP2_MAX_SEG_SIZE		0xfffc
204
205/* Unit directory keys */
206#define SBP2_CSR_UNIT_CHARACTERISTICS	0x3a
207#define SBP2_CSR_FIRMWARE_REVISION	0x3c
208#define SBP2_CSR_LOGICAL_UNIT_NUMBER	0x14
209#define SBP2_CSR_UNIT_UNIQUE_ID		0x8d
210#define SBP2_CSR_LOGICAL_UNIT_DIRECTORY	0xd4
211
212/* Management orb opcodes */
213#define SBP2_LOGIN_REQUEST		0x0
214#define SBP2_QUERY_LOGINS_REQUEST	0x1
215#define SBP2_RECONNECT_REQUEST		0x3
216#define SBP2_SET_PASSWORD_REQUEST	0x4
217#define SBP2_LOGOUT_REQUEST		0x7
218#define SBP2_ABORT_TASK_REQUEST		0xb
219#define SBP2_ABORT_TASK_SET		0xc
220#define SBP2_LOGICAL_UNIT_RESET		0xe
221#define SBP2_TARGET_RESET_REQUEST	0xf
222
223/* Offsets for command block agent registers */
224#define SBP2_AGENT_STATE		0x00
225#define SBP2_AGENT_RESET		0x04
226#define SBP2_ORB_POINTER		0x08
227#define SBP2_DOORBELL			0x10
228#define SBP2_UNSOLICITED_STATUS_ENABLE	0x14
229
230/* Status write response codes */
231#define SBP2_STATUS_REQUEST_COMPLETE	0x0
232#define SBP2_STATUS_TRANSPORT_FAILURE	0x1
233#define SBP2_STATUS_ILLEGAL_REQUEST	0x2
234#define SBP2_STATUS_VENDOR_DEPENDENT	0x3
235
236#define STATUS_GET_ORB_HIGH(v)		((v).status & 0xffff)
237#define STATUS_GET_SBP_STATUS(v)	(((v).status >> 16) & 0xff)
238#define STATUS_GET_LEN(v)		(((v).status >> 24) & 0x07)
239#define STATUS_GET_DEAD(v)		(((v).status >> 27) & 0x01)
240#define STATUS_GET_RESPONSE(v)		(((v).status >> 28) & 0x03)
241#define STATUS_GET_SOURCE(v)		(((v).status >> 30) & 0x03)
242#define STATUS_GET_ORB_LOW(v)		((v).orb_low)
243#define STATUS_GET_DATA(v)		((v).data)
244
245struct sbp2_status {
246	u32 status;
247	u32 orb_low;
248	u8 data[24];
249};
250
251struct sbp2_pointer {
252	__be32 high;
253	__be32 low;
254};
255
256struct sbp2_orb {
257	struct fw_transaction t;
258	struct kref kref;
259	dma_addr_t request_bus;
260	int rcode;
261	void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
262	struct sbp2_logical_unit *lu;
263	struct list_head link;
264};
265
266#define MANAGEMENT_ORB_LUN(v)			((v))
267#define MANAGEMENT_ORB_FUNCTION(v)		((v) << 16)
268#define MANAGEMENT_ORB_RECONNECT(v)		((v) << 20)
269#define MANAGEMENT_ORB_EXCLUSIVE(v)		((v) ? 1 << 28 : 0)
270#define MANAGEMENT_ORB_REQUEST_FORMAT(v)	((v) << 29)
271#define MANAGEMENT_ORB_NOTIFY			((1) << 31)
272
273#define MANAGEMENT_ORB_RESPONSE_LENGTH(v)	((v))
274#define MANAGEMENT_ORB_PASSWORD_LENGTH(v)	((v) << 16)
275
276struct sbp2_management_orb {
277	struct sbp2_orb base;
278	struct {
279		struct sbp2_pointer password;
280		struct sbp2_pointer response;
281		__be32 misc;
282		__be32 length;
283		struct sbp2_pointer status_fifo;
284	} request;
285	__be32 response[4];
286	dma_addr_t response_bus;
287	struct completion done;
288	struct sbp2_status status;
289};
290
291struct sbp2_login_response {
292	__be32 misc;
293	struct sbp2_pointer command_block_agent;
294	__be32 reconnect_hold;
295};
296#define COMMAND_ORB_DATA_SIZE(v)	((v))
297#define COMMAND_ORB_PAGE_SIZE(v)	((v) << 16)
298#define COMMAND_ORB_PAGE_TABLE_PRESENT	((1) << 19)
299#define COMMAND_ORB_MAX_PAYLOAD(v)	((v) << 20)
300#define COMMAND_ORB_SPEED(v)		((v) << 24)
301#define COMMAND_ORB_DIRECTION		((1) << 27)
302#define COMMAND_ORB_REQUEST_FORMAT(v)	((v) << 29)
303#define COMMAND_ORB_NOTIFY		((1) << 31)
304
305struct sbp2_command_orb {
306	struct sbp2_orb base;
307	struct {
308		struct sbp2_pointer next;
309		struct sbp2_pointer data_descriptor;
310		__be32 misc;
311		u8 command_block[SBP2_MAX_CDB_SIZE];
312	} request;
313	struct scsi_cmnd *cmd;
314
315	struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
316	dma_addr_t page_table_bus;
317};
318
319#define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
320#define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
321
322/*
323 * List of devices with known bugs.
324 *
325 * The firmware_revision field, masked with 0xffff00, is the best
326 * indicator for the type of bridge chip of a device.  It yields a few
327 * false positives but this did not break correctly behaving devices
328 * so far.
329 */
330static const struct {
331	u32 firmware_revision;
332	u32 model;
333	unsigned int workarounds;
334} sbp2_workarounds_table[] = {
335	/* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
336		.firmware_revision	= 0x002800,
337		.model			= 0x001010,
338		.workarounds		= SBP2_WORKAROUND_INQUIRY_36 |
339					  SBP2_WORKAROUND_MODE_SENSE_8 |
340					  SBP2_WORKAROUND_POWER_CONDITION,
341	},
342	/* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
343		.firmware_revision	= 0x002800,
344		.model			= 0x000000,
345		.workarounds		= SBP2_WORKAROUND_POWER_CONDITION,
346	},
347	/* Initio bridges, actually only needed for some older ones */ {
348		.firmware_revision	= 0x000200,
349		.model			= SBP2_ROM_VALUE_WILDCARD,
350		.workarounds		= SBP2_WORKAROUND_INQUIRY_36,
351	},
352	/* PL-3507 bridge with Prolific firmware */ {
353		.firmware_revision	= 0x012800,
354		.model			= SBP2_ROM_VALUE_WILDCARD,
355		.workarounds		= SBP2_WORKAROUND_POWER_CONDITION,
356	},
357	/* Symbios bridge */ {
358		.firmware_revision	= 0xa0b800,
359		.model			= SBP2_ROM_VALUE_WILDCARD,
360		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS,
361	},
362	/* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
363		.firmware_revision	= 0x002600,
364		.model			= SBP2_ROM_VALUE_WILDCARD,
365		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS,
366	},
367	/*
368	 * iPod 2nd generation: needs 128k max transfer size workaround
369	 * iPod 3rd generation: needs fix capacity workaround
370	 */
371	{
372		.firmware_revision	= 0x0a2700,
373		.model			= 0x000000,
374		.workarounds		= SBP2_WORKAROUND_128K_MAX_TRANS |
375					  SBP2_WORKAROUND_FIX_CAPACITY,
376	},
377	/* iPod 4th generation */ {
378		.firmware_revision	= 0x0a2700,
379		.model			= 0x000021,
380		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
381	},
382	/* iPod mini */ {
383		.firmware_revision	= 0x0a2700,
384		.model			= 0x000022,
385		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
386	},
387	/* iPod mini */ {
388		.firmware_revision	= 0x0a2700,
389		.model			= 0x000023,
390		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
391	},
392	/* iPod Photo */ {
393		.firmware_revision	= 0x0a2700,
394		.model			= 0x00007e,
395		.workarounds		= SBP2_WORKAROUND_FIX_CAPACITY,
396	}
397};
398
399static void free_orb(struct kref *kref)
400{
401	struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
402
403	kfree(orb);
404}
405
406static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
407			      int tcode, int destination, int source,
408			      int generation, unsigned long long offset,
409			      void *payload, size_t length, void *callback_data)
410{
411	struct sbp2_logical_unit *lu = callback_data;
412	struct sbp2_orb *orb = NULL, *iter;
413	struct sbp2_status status;
414	unsigned long flags;
415
416	if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
417	    length < 8 || length > sizeof(status)) {
418		fw_send_response(card, request, RCODE_TYPE_ERROR);
419		return;
420	}
421
422	status.status  = be32_to_cpup(payload);
423	status.orb_low = be32_to_cpup(payload + 4);
424	memset(status.data, 0, sizeof(status.data));
425	if (length > 8)
426		memcpy(status.data, payload + 8, length - 8);
427
428	if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
429		dev_notice(lu_dev(lu),
430			   "non-ORB related status write, not handled\n");
431		fw_send_response(card, request, RCODE_COMPLETE);
432		return;
433	}
434
435	/* Lookup the orb corresponding to this status write. */
436	spin_lock_irqsave(&lu->tgt->lock, flags);
437	list_for_each_entry(iter, &lu->orb_list, link) {
438		if (STATUS_GET_ORB_HIGH(status) == 0 &&
439		    STATUS_GET_ORB_LOW(status) == iter->request_bus) {
440			iter->rcode = RCODE_COMPLETE;
441			list_del(&iter->link);
442			orb = iter;
443			break;
444		}
445	}
446	spin_unlock_irqrestore(&lu->tgt->lock, flags);
447
448	if (orb) {
449		orb->callback(orb, &status);
450		kref_put(&orb->kref, free_orb); /* orb callback reference */
451	} else {
452		dev_err(lu_dev(lu), "status write for unknown ORB\n");
453	}
454
455	fw_send_response(card, request, RCODE_COMPLETE);
456}
457
458static void complete_transaction(struct fw_card *card, int rcode,
459				 void *payload, size_t length, void *data)
460{
461	struct sbp2_orb *orb = data;
462	unsigned long flags;
463
464	/*
465	 * This is a little tricky.  We can get the status write for
466	 * the orb before we get this callback.  The status write
467	 * handler above will assume the orb pointer transaction was
468	 * successful and set the rcode to RCODE_COMPLETE for the orb.
469	 * So this callback only sets the rcode if it hasn't already
470	 * been set and only does the cleanup if the transaction
471	 * failed and we didn't already get a status write.
472	 */
473	spin_lock_irqsave(&orb->lu->tgt->lock, flags);
474
475	if (orb->rcode == -1)
476		orb->rcode = rcode;
477	if (orb->rcode != RCODE_COMPLETE) {
478		list_del(&orb->link);
479		spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
480
481		orb->callback(orb, NULL);
482		kref_put(&orb->kref, free_orb); /* orb callback reference */
483	} else {
484		spin_unlock_irqrestore(&orb->lu->tgt->lock, flags);
485	}
486
487	kref_put(&orb->kref, free_orb); /* transaction callback reference */
488}
489
490static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
491			  int node_id, int generation, u64 offset)
492{
493	struct fw_device *device = target_parent_device(lu->tgt);
494	struct sbp2_pointer orb_pointer;
495	unsigned long flags;
496
497	orb_pointer.high = 0;
498	orb_pointer.low = cpu_to_be32(orb->request_bus);
499
500	orb->lu = lu;
501	spin_lock_irqsave(&lu->tgt->lock, flags);
502	list_add_tail(&orb->link, &lu->orb_list);
503	spin_unlock_irqrestore(&lu->tgt->lock, flags);
504
505	kref_get(&orb->kref); /* transaction callback reference */
506	kref_get(&orb->kref); /* orb callback reference */
507
508	fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
509			node_id, generation, device->max_speed, offset,
510			&orb_pointer, 8, complete_transaction, orb);
511}
512
513static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
514{
515	struct fw_device *device = target_parent_device(lu->tgt);
516	struct sbp2_orb *orb, *next;
517	struct list_head list;
518	int retval = -ENOENT;
519
520	INIT_LIST_HEAD(&list);
521	spin_lock_irq(&lu->tgt->lock);
522	list_splice_init(&lu->orb_list, &list);
523	spin_unlock_irq(&lu->tgt->lock);
524
525	list_for_each_entry_safe(orb, next, &list, link) {
526		retval = 0;
527		if (fw_cancel_transaction(device->card, &orb->t) == 0)
528			continue;
529
530		orb->rcode = RCODE_CANCELLED;
531		orb->callback(orb, NULL);
532		kref_put(&orb->kref, free_orb); /* orb callback reference */
533	}
534
535	return retval;
536}
537
538static void complete_management_orb(struct sbp2_orb *base_orb,
539				    struct sbp2_status *status)
540{
541	struct sbp2_management_orb *orb =
542		container_of(base_orb, struct sbp2_management_orb, base);
543
544	if (status)
545		memcpy(&orb->status, status, sizeof(*status));
546	complete(&orb->done);
547}
548
549static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
550				    int generation, int function,
551				    int lun_or_login_id, void *response)
552{
553	struct fw_device *device = target_parent_device(lu->tgt);
554	struct sbp2_management_orb *orb;
555	unsigned int timeout;
556	int retval = -ENOMEM;
557
558	if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
559		return 0;
560
561	orb = kzalloc(sizeof(*orb), GFP_NOIO);
562	if (orb == NULL)
563		return -ENOMEM;
564
565	kref_init(&orb->base.kref);
566	orb->response_bus =
567		dma_map_single(device->card->device, &orb->response,
568			       sizeof(orb->response), DMA_FROM_DEVICE);
569	if (dma_mapping_error(device->card->device, orb->response_bus))
570		goto fail_mapping_response;
571
572	orb->request.response.high = 0;
573	orb->request.response.low  = cpu_to_be32(orb->response_bus);
574
575	orb->request.misc = cpu_to_be32(
576		MANAGEMENT_ORB_NOTIFY |
577		MANAGEMENT_ORB_FUNCTION(function) |
578		MANAGEMENT_ORB_LUN(lun_or_login_id));
579	orb->request.length = cpu_to_be32(
580		MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
581
582	orb->request.status_fifo.high =
583		cpu_to_be32(lu->address_handler.offset >> 32);
584	orb->request.status_fifo.low  =
585		cpu_to_be32(lu->address_handler.offset);
586
587	if (function == SBP2_LOGIN_REQUEST) {
588		/* Ask for 2^2 == 4 seconds reconnect grace period */
589		orb->request.misc |= cpu_to_be32(
590			MANAGEMENT_ORB_RECONNECT(2) |
591			MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
592		timeout = lu->tgt->mgt_orb_timeout;
593	} else {
594		timeout = SBP2_ORB_TIMEOUT;
595	}
596
597	init_completion(&orb->done);
598	orb->base.callback = complete_management_orb;
599
600	orb->base.request_bus =
601		dma_map_single(device->card->device, &orb->request,
602			       sizeof(orb->request), DMA_TO_DEVICE);
603	if (dma_mapping_error(device->card->device, orb->base.request_bus))
604		goto fail_mapping_request;
605
606	sbp2_send_orb(&orb->base, lu, node_id, generation,
607		      lu->tgt->management_agent_address);
608
609	wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
610
611	retval = -EIO;
612	if (sbp2_cancel_orbs(lu) == 0) {
613		dev_err(lu_dev(lu), "ORB reply timed out, rcode 0x%02x\n",
614			orb->base.rcode);
615		goto out;
616	}
617
618	if (orb->base.rcode != RCODE_COMPLETE) {
619		dev_err(lu_dev(lu), "management write failed, rcode 0x%02x\n",
620			orb->base.rcode);
621		goto out;
622	}
623
624	if (STATUS_GET_RESPONSE(orb->status) != 0 ||
625	    STATUS_GET_SBP_STATUS(orb->status) != 0) {
626		dev_err(lu_dev(lu), "error status: %d:%d\n",
627			 STATUS_GET_RESPONSE(orb->status),
628			 STATUS_GET_SBP_STATUS(orb->status));
629		goto out;
630	}
631
632	retval = 0;
633 out:
634	dma_unmap_single(device->card->device, orb->base.request_bus,
635			 sizeof(orb->request), DMA_TO_DEVICE);
636 fail_mapping_request:
637	dma_unmap_single(device->card->device, orb->response_bus,
638			 sizeof(orb->response), DMA_FROM_DEVICE);
639 fail_mapping_response:
640	if (response)
641		memcpy(response, orb->response, sizeof(orb->response));
642	kref_put(&orb->base.kref, free_orb);
643
644	return retval;
645}
646
647static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
648{
649	struct fw_device *device = target_parent_device(lu->tgt);
650	__be32 d = 0;
651
652	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
653			   lu->tgt->node_id, lu->generation, device->max_speed,
654			   lu->command_block_agent_address + SBP2_AGENT_RESET,
655			   &d, 4);
656}
657
658static void complete_agent_reset_write_no_wait(struct fw_card *card,
659		int rcode, void *payload, size_t length, void *data)
660{
661	kfree(data);
662}
663
664static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
665{
666	struct fw_device *device = target_parent_device(lu->tgt);
667	struct fw_transaction *t;
668	static __be32 d;
669
670	t = kmalloc(sizeof(*t), GFP_ATOMIC);
671	if (t == NULL)
672		return;
673
674	fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
675			lu->tgt->node_id, lu->generation, device->max_speed,
676			lu->command_block_agent_address + SBP2_AGENT_RESET,
677			&d, 4, complete_agent_reset_write_no_wait, t);
678}
679
680static inline void sbp2_allow_block(struct sbp2_target *tgt)
681{
682	spin_lock_irq(&tgt->lock);
683	--tgt->dont_block;
684	spin_unlock_irq(&tgt->lock);
685}
686
687/*
688 * Blocks lu->tgt if all of the following conditions are met:
689 *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
690 *     logical units have been finished (indicated by dont_block == 0).
691 *   - lu->generation is stale.
692 *
693 * Note, scsi_block_requests() must be called while holding tgt->lock,
694 * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
695 * unblock the target.
696 */
697static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
698{
699	struct sbp2_target *tgt = lu->tgt;
700	struct fw_card *card = target_parent_device(tgt)->card;
701	struct Scsi_Host *shost =
702		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
703	unsigned long flags;
704
705	spin_lock_irqsave(&tgt->lock, flags);
706	if (!tgt->dont_block && !lu->blocked &&
707	    lu->generation != card->generation) {
708		lu->blocked = true;
709		if (++tgt->blocked == 1)
710			scsi_block_requests(shost);
711	}
712	spin_unlock_irqrestore(&tgt->lock, flags);
713}
714
715/*
716 * Unblocks lu->tgt as soon as all its logical units can be unblocked.
717 * Note, it is harmless to run scsi_unblock_requests() outside the
718 * tgt->lock protected section.  On the other hand, running it inside
719 * the section might clash with shost->host_lock.
720 */
721static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
722{
723	struct sbp2_target *tgt = lu->tgt;
724	struct fw_card *card = target_parent_device(tgt)->card;
725	struct Scsi_Host *shost =
726		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
727	bool unblock = false;
728
729	spin_lock_irq(&tgt->lock);
730	if (lu->blocked && lu->generation == card->generation) {
731		lu->blocked = false;
732		unblock = --tgt->blocked == 0;
733	}
734	spin_unlock_irq(&tgt->lock);
735
736	if (unblock)
737		scsi_unblock_requests(shost);
738}
739
740/*
741 * Prevents future blocking of tgt and unblocks it.
742 * Note, it is harmless to run scsi_unblock_requests() outside the
743 * tgt->lock protected section.  On the other hand, running it inside
744 * the section might clash with shost->host_lock.
745 */
746static void sbp2_unblock(struct sbp2_target *tgt)
747{
748	struct Scsi_Host *shost =
749		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
750
751	spin_lock_irq(&tgt->lock);
752	++tgt->dont_block;
753	spin_unlock_irq(&tgt->lock);
754
755	scsi_unblock_requests(shost);
756}
757
758static int sbp2_lun2int(u16 lun)
759{
760	struct scsi_lun eight_bytes_lun;
761
762	memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
763	eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
764	eight_bytes_lun.scsi_lun[1] = lun & 0xff;
765
766	return scsilun_to_int(&eight_bytes_lun);
767}
768
769/*
770 * Write retransmit retry values into the BUSY_TIMEOUT register.
771 * - The single-phase retry protocol is supported by all SBP-2 devices, but the
772 *   default retry_limit value is 0 (i.e. never retry transmission). We write a
773 *   saner value after logging into the device.
774 * - The dual-phase retry protocol is optional to implement, and if not
775 *   supported, writes to the dual-phase portion of the register will be
776 *   ignored. We try to write the original 1394-1995 default here.
777 * - In the case of devices that are also SBP-3-compliant, all writes are
778 *   ignored, as the register is read-only, but contains single-phase retry of
779 *   15, which is what we're trying to set for all SBP-2 device anyway, so this
780 *   write attempt is safe and yields more consistent behavior for all devices.
781 *
782 * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
783 * and section 6.4 of the SBP-3 spec for further details.
784 */
785static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
786{
787	struct fw_device *device = target_parent_device(lu->tgt);
788	__be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
789
790	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
791			   lu->tgt->node_id, lu->generation, device->max_speed,
792			   CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
793}
794
795static void sbp2_reconnect(struct work_struct *work);
796
797static void sbp2_login(struct work_struct *work)
798{
799	struct sbp2_logical_unit *lu =
800		container_of(work, struct sbp2_logical_unit, work.work);
801	struct sbp2_target *tgt = lu->tgt;
802	struct fw_device *device = target_parent_device(tgt);
803	struct Scsi_Host *shost;
804	struct scsi_device *sdev;
805	struct sbp2_login_response response;
806	int generation, node_id, local_node_id;
807
808	if (fw_device_is_shutdown(device))
809		return;
810
811	generation    = device->generation;
812	smp_rmb();    /* node IDs must not be older than generation */
813	node_id       = device->node_id;
814	local_node_id = device->card->node_id;
815
816	/* If this is a re-login attempt, log out, or we might be rejected. */
817	if (lu->has_sdev)
818		sbp2_send_management_orb(lu, device->node_id, generation,
819				SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
820
821	if (sbp2_send_management_orb(lu, node_id, generation,
822				SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
823		if (lu->retries++ < 5) {
824			sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
825		} else {
826			dev_err(tgt_dev(tgt), "failed to login to LUN %04x\n",
827				lu->lun);
828			/* Let any waiting I/O fail from now on. */
829			sbp2_unblock(lu->tgt);
830		}
831		return;
832	}
833
834	tgt->node_id	  = node_id;
835	tgt->address_high = local_node_id << 16;
836	smp_wmb();	  /* node IDs must not be older than generation */
837	lu->generation	  = generation;
838
839	lu->command_block_agent_address =
840		((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
841		      << 32) | be32_to_cpu(response.command_block_agent.low);
842	lu->login_id = be32_to_cpu(response.misc) & 0xffff;
843
844	dev_notice(tgt_dev(tgt), "logged in to LUN %04x (%d retries)\n",
845		   lu->lun, lu->retries);
846
847	/* set appropriate retry limit(s) in BUSY_TIMEOUT register */
848	sbp2_set_busy_timeout(lu);
849
850	lu->workfn = sbp2_reconnect;
851	sbp2_agent_reset(lu);
852
853	/* This was a re-login. */
854	if (lu->has_sdev) {
855		sbp2_cancel_orbs(lu);
856		sbp2_conditionally_unblock(lu);
857
858		return;
859	}
860
861	if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
862		ssleep(SBP2_INQUIRY_DELAY);
863
864	shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
865	sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
866	/*
867	 * FIXME:  We are unable to perform reconnects while in sbp2_login().
868	 * Therefore __scsi_add_device() will get into trouble if a bus reset
869	 * happens in parallel.  It will either fail or leave us with an
870	 * unusable sdev.  As a workaround we check for this and retry the
871	 * whole login and SCSI probing.
872	 */
873
874	/* Reported error during __scsi_add_device() */
875	if (IS_ERR(sdev))
876		goto out_logout_login;
877
878	/* Unreported error during __scsi_add_device() */
879	smp_rmb(); /* get current card generation */
880	if (generation != device->card->generation) {
881		scsi_remove_device(sdev);
882		scsi_device_put(sdev);
883		goto out_logout_login;
884	}
885
886	/* No error during __scsi_add_device() */
887	lu->has_sdev = true;
888	scsi_device_put(sdev);
889	sbp2_allow_block(tgt);
890
891	return;
892
893 out_logout_login:
894	smp_rmb(); /* generation may have changed */
895	generation = device->generation;
896	smp_rmb(); /* node_id must not be older than generation */
897
898	sbp2_send_management_orb(lu, device->node_id, generation,
899				 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
900	/*
901	 * If a bus reset happened, sbp2_update will have requeued
902	 * lu->work already.  Reset the work from reconnect to login.
903	 */
904	lu->workfn = sbp2_login;
905}
906
907static void sbp2_reconnect(struct work_struct *work)
908{
909	struct sbp2_logical_unit *lu =
910		container_of(work, struct sbp2_logical_unit, work.work);
911	struct sbp2_target *tgt = lu->tgt;
912	struct fw_device *device = target_parent_device(tgt);
913	int generation, node_id, local_node_id;
914
915	if (fw_device_is_shutdown(device))
916		return;
917
918	generation    = device->generation;
919	smp_rmb();    /* node IDs must not be older than generation */
920	node_id       = device->node_id;
921	local_node_id = device->card->node_id;
922
923	if (sbp2_send_management_orb(lu, node_id, generation,
924				     SBP2_RECONNECT_REQUEST,
925				     lu->login_id, NULL) < 0) {
926		/*
927		 * If reconnect was impossible even though we are in the
928		 * current generation, fall back and try to log in again.
929		 *
930		 * We could check for "Function rejected" status, but
931		 * looking at the bus generation as simpler and more general.
932		 */
933		smp_rmb(); /* get current card generation */
934		if (generation == device->card->generation ||
935		    lu->retries++ >= 5) {
936			dev_err(tgt_dev(tgt), "failed to reconnect\n");
937			lu->retries = 0;
938			lu->workfn = sbp2_login;
939		}
940		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
941
942		return;
943	}
944
945	tgt->node_id      = node_id;
946	tgt->address_high = local_node_id << 16;
947	smp_wmb();	  /* node IDs must not be older than generation */
948	lu->generation	  = generation;
949
950	dev_notice(tgt_dev(tgt), "reconnected to LUN %04x (%d retries)\n",
951		   lu->lun, lu->retries);
952
953	sbp2_agent_reset(lu);
954	sbp2_cancel_orbs(lu);
955	sbp2_conditionally_unblock(lu);
956}
957
958static void sbp2_lu_workfn(struct work_struct *work)
959{
960	struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
961						struct sbp2_logical_unit, work);
962	lu->workfn(work);
963}
964
965static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
966{
967	struct sbp2_logical_unit *lu;
968
969	lu = kmalloc(sizeof(*lu), GFP_KERNEL);
970	if (!lu)
971		return -ENOMEM;
972
973	lu->address_handler.length           = 0x100;
974	lu->address_handler.address_callback = sbp2_status_write;
975	lu->address_handler.callback_data    = lu;
976
977	if (fw_core_add_address_handler(&lu->address_handler,
978					&fw_high_memory_region) < 0) {
979		kfree(lu);
980		return -ENOMEM;
981	}
982
983	lu->tgt      = tgt;
984	lu->lun      = lun_entry & 0xffff;
985	lu->login_id = INVALID_LOGIN_ID;
986	lu->retries  = 0;
987	lu->has_sdev = false;
988	lu->blocked  = false;
989	++tgt->dont_block;
990	INIT_LIST_HEAD(&lu->orb_list);
991	lu->workfn = sbp2_login;
992	INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
993
994	list_add_tail(&lu->link, &tgt->lu_list);
995	return 0;
996}
997
998static void sbp2_get_unit_unique_id(struct sbp2_target *tgt,
999				    const u32 *leaf)
1000{
1001	if ((leaf[0] & 0xffff0000) == 0x00020000)
1002		tgt->guid = (u64)leaf[1] << 32 | leaf[2];
1003}
1004
1005static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1006				      const u32 *directory)
1007{
1008	struct fw_csr_iterator ci;
1009	int key, value;
1010
1011	fw_csr_iterator_init(&ci, directory);
1012	while (fw_csr_iterator_next(&ci, &key, &value))
1013		if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1014		    sbp2_add_logical_unit(tgt, value) < 0)
1015			return -ENOMEM;
1016	return 0;
1017}
1018
1019static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1020			      u32 *model, u32 *firmware_revision)
1021{
1022	struct fw_csr_iterator ci;
1023	int key, value;
1024
1025	fw_csr_iterator_init(&ci, directory);
1026	while (fw_csr_iterator_next(&ci, &key, &value)) {
1027		switch (key) {
1028
1029		case CSR_DEPENDENT_INFO | CSR_OFFSET:
1030			tgt->management_agent_address =
1031					CSR_REGISTER_BASE + 4 * value;
1032			break;
1033
1034		case CSR_DIRECTORY_ID:
1035			tgt->directory_id = value;
1036			break;
1037
1038		case CSR_MODEL:
1039			*model = value;
1040			break;
1041
1042		case SBP2_CSR_FIRMWARE_REVISION:
1043			*firmware_revision = value;
1044			break;
1045
1046		case SBP2_CSR_UNIT_CHARACTERISTICS:
1047			/* the timeout value is stored in 500ms units */
1048			tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1049			break;
1050
1051		case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1052			if (sbp2_add_logical_unit(tgt, value) < 0)
1053				return -ENOMEM;
1054			break;
1055
1056		case SBP2_CSR_UNIT_UNIQUE_ID:
1057			sbp2_get_unit_unique_id(tgt, ci.p - 1 + value);
1058			break;
1059
1060		case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1061			/* Adjust for the increment in the iterator */
1062			if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1063				return -ENOMEM;
1064			break;
1065		}
1066	}
1067	return 0;
1068}
1069
1070/*
1071 * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1072 * provided in the config rom. Most devices do provide a value, which
1073 * we'll use for login management orbs, but with some sane limits.
1074 */
1075static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1076{
1077	unsigned int timeout = tgt->mgt_orb_timeout;
1078
1079	if (timeout > 40000)
1080		dev_notice(tgt_dev(tgt), "%ds mgt_ORB_timeout limited to 40s\n",
1081			   timeout / 1000);
1082
1083	tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1084}
1085
1086static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1087				  u32 firmware_revision)
1088{
1089	int i;
1090	unsigned int w = sbp2_param_workarounds;
1091
1092	if (w)
1093		dev_notice(tgt_dev(tgt),
1094			   "Please notify linux1394-devel@lists.sf.net "
1095			   "if you need the workarounds parameter\n");
1096
1097	if (w & SBP2_WORKAROUND_OVERRIDE)
1098		goto out;
1099
1100	for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1101
1102		if (sbp2_workarounds_table[i].firmware_revision !=
1103		    (firmware_revision & 0xffffff00))
1104			continue;
1105
1106		if (sbp2_workarounds_table[i].model != model &&
1107		    sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1108			continue;
1109
1110		w |= sbp2_workarounds_table[i].workarounds;
1111		break;
1112	}
1113 out:
1114	if (w)
1115		dev_notice(tgt_dev(tgt), "workarounds 0x%x "
1116			   "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1117			   w, firmware_revision, model);
1118	tgt->workarounds = w;
1119}
1120
1121static const struct scsi_host_template scsi_driver_template;
1122static void sbp2_remove(struct fw_unit *unit);
1123
1124static int sbp2_probe(struct fw_unit *unit, const struct ieee1394_device_id *id)
1125{
1126	struct fw_device *device = fw_parent_device(unit);
1127	struct sbp2_target *tgt;
1128	struct sbp2_logical_unit *lu;
1129	struct Scsi_Host *shost;
1130	u32 model, firmware_revision;
1131
1132	/* cannot (or should not) handle targets on the local node */
1133	if (device->is_local)
1134		return -ENODEV;
1135
1136	shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1137	if (shost == NULL)
1138		return -ENOMEM;
1139
1140	tgt = (struct sbp2_target *)shost->hostdata;
1141	dev_set_drvdata(&unit->device, tgt);
1142	tgt->unit = unit;
1143	INIT_LIST_HEAD(&tgt->lu_list);
1144	spin_lock_init(&tgt->lock);
1145	tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1146
1147	if (fw_device_enable_phys_dma(device) < 0)
1148		goto fail_shost_put;
1149
1150	shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1151
1152	if (scsi_add_host_with_dma(shost, &unit->device,
1153				   device->card->device) < 0)
1154		goto fail_shost_put;
1155
1156	/* implicit directory ID */
1157	tgt->directory_id = ((unit->directory - device->config_rom) * 4
1158			     + CSR_CONFIG_ROM) & 0xffffff;
1159
1160	firmware_revision = SBP2_ROM_VALUE_MISSING;
1161	model		  = SBP2_ROM_VALUE_MISSING;
1162
1163	if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1164			       &firmware_revision) < 0)
1165		goto fail_remove;
1166
1167	sbp2_clamp_management_orb_timeout(tgt);
1168	sbp2_init_workarounds(tgt, model, firmware_revision);
1169
1170	/*
1171	 * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1172	 * and so on up to 4096 bytes.  The SBP-2 max_payload field
1173	 * specifies the max payload size as 2 ^ (max_payload + 2), so
1174	 * if we set this to max_speed + 7, we get the right value.
1175	 */
1176	tgt->max_payload = min3(device->max_speed + 7, 10U,
1177				device->card->max_receive - 1);
1178
1179	/* Do the login in a workqueue so we can easily reschedule retries. */
1180	list_for_each_entry(lu, &tgt->lu_list, link)
1181		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1182
1183	return 0;
1184
1185 fail_remove:
1186	sbp2_remove(unit);
1187	return -ENOMEM;
1188
1189 fail_shost_put:
1190	scsi_host_put(shost);
1191	return -ENOMEM;
1192}
1193
1194static void sbp2_update(struct fw_unit *unit)
1195{
1196	struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1197	struct sbp2_logical_unit *lu;
1198
1199	fw_device_enable_phys_dma(fw_parent_device(unit));
1200
1201	/*
1202	 * Fw-core serializes sbp2_update() against sbp2_remove().
1203	 * Iteration over tgt->lu_list is therefore safe here.
1204	 */
1205	list_for_each_entry(lu, &tgt->lu_list, link) {
1206		sbp2_conditionally_block(lu);
1207		lu->retries = 0;
1208		sbp2_queue_work(lu, 0);
1209	}
1210}
1211
1212static void sbp2_remove(struct fw_unit *unit)
1213{
1214	struct fw_device *device = fw_parent_device(unit);
1215	struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1216	struct sbp2_logical_unit *lu, *next;
1217	struct Scsi_Host *shost =
1218		container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
1219	struct scsi_device *sdev;
1220
1221	/* prevent deadlocks */
1222	sbp2_unblock(tgt);
1223
1224	list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
1225		cancel_delayed_work_sync(&lu->work);
1226		sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
1227		if (sdev) {
1228			scsi_remove_device(sdev);
1229			scsi_device_put(sdev);
1230		}
1231		if (lu->login_id != INVALID_LOGIN_ID) {
1232			int generation, node_id;
1233			/*
1234			 * tgt->node_id may be obsolete here if we failed
1235			 * during initial login or after a bus reset where
1236			 * the topology changed.
1237			 */
1238			generation = device->generation;
1239			smp_rmb(); /* node_id vs. generation */
1240			node_id    = device->node_id;
1241			sbp2_send_management_orb(lu, node_id, generation,
1242						 SBP2_LOGOUT_REQUEST,
1243						 lu->login_id, NULL);
1244		}
1245		fw_core_remove_address_handler(&lu->address_handler);
1246		list_del(&lu->link);
1247		kfree(lu);
1248	}
1249	scsi_remove_host(shost);
1250	dev_notice(&unit->device, "released target %d:0:0\n", shost->host_no);
1251
1252	scsi_host_put(shost);
1253}
1254
1255#define SBP2_UNIT_SPEC_ID_ENTRY	0x0000609e
1256#define SBP2_SW_VERSION_ENTRY	0x00010483
1257
1258static const struct ieee1394_device_id sbp2_id_table[] = {
1259	{
1260		.match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1261				IEEE1394_MATCH_VERSION,
1262		.specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1263		.version      = SBP2_SW_VERSION_ENTRY,
1264	},
1265	{ }
1266};
1267
1268static struct fw_driver sbp2_driver = {
1269	.driver   = {
1270		.owner  = THIS_MODULE,
1271		.name   = KBUILD_MODNAME,
1272		.bus    = &fw_bus_type,
1273	},
1274	.probe    = sbp2_probe,
1275	.update   = sbp2_update,
1276	.remove   = sbp2_remove,
1277	.id_table = sbp2_id_table,
1278};
1279
1280static void sbp2_unmap_scatterlist(struct device *card_device,
1281				   struct sbp2_command_orb *orb)
1282{
1283	scsi_dma_unmap(orb->cmd);
1284
1285	if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1286		dma_unmap_single(card_device, orb->page_table_bus,
1287				 sizeof(orb->page_table), DMA_TO_DEVICE);
1288}
1289
1290static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1291{
1292	int sam_status;
1293	int sfmt = (sbp2_status[0] >> 6) & 0x03;
1294
1295	if (sfmt == 2 || sfmt == 3) {
1296		/*
1297		 * Reserved for future standardization (2) or
1298		 * Status block format vendor-dependent (3)
1299		 */
1300		return DID_ERROR << 16;
1301	}
1302
1303	sense_data[0] = 0x70 | sfmt | (sbp2_status[1] & 0x80);
1304	sense_data[1] = 0x0;
1305	sense_data[2] = ((sbp2_status[1] << 1) & 0xe0) | (sbp2_status[1] & 0x0f);
1306	sense_data[3] = sbp2_status[4];
1307	sense_data[4] = sbp2_status[5];
1308	sense_data[5] = sbp2_status[6];
1309	sense_data[6] = sbp2_status[7];
1310	sense_data[7] = 10;
1311	sense_data[8] = sbp2_status[8];
1312	sense_data[9] = sbp2_status[9];
1313	sense_data[10] = sbp2_status[10];
1314	sense_data[11] = sbp2_status[11];
1315	sense_data[12] = sbp2_status[2];
1316	sense_data[13] = sbp2_status[3];
1317	sense_data[14] = sbp2_status[12];
1318	sense_data[15] = sbp2_status[13];
1319
1320	sam_status = sbp2_status[0] & 0x3f;
1321
1322	switch (sam_status) {
1323	case SAM_STAT_GOOD:
1324	case SAM_STAT_CHECK_CONDITION:
1325	case SAM_STAT_CONDITION_MET:
1326	case SAM_STAT_BUSY:
1327	case SAM_STAT_RESERVATION_CONFLICT:
1328	case SAM_STAT_COMMAND_TERMINATED:
1329		return DID_OK << 16 | sam_status;
1330
1331	default:
1332		return DID_ERROR << 16;
1333	}
1334}
1335
1336static void complete_command_orb(struct sbp2_orb *base_orb,
1337				 struct sbp2_status *status)
1338{
1339	struct sbp2_command_orb *orb =
1340		container_of(base_orb, struct sbp2_command_orb, base);
1341	struct fw_device *device = target_parent_device(base_orb->lu->tgt);
1342	int result;
1343
1344	if (status != NULL) {
1345		if (STATUS_GET_DEAD(*status))
1346			sbp2_agent_reset_no_wait(base_orb->lu);
1347
1348		switch (STATUS_GET_RESPONSE(*status)) {
1349		case SBP2_STATUS_REQUEST_COMPLETE:
1350			result = DID_OK << 16;
1351			break;
1352		case SBP2_STATUS_TRANSPORT_FAILURE:
1353			result = DID_BUS_BUSY << 16;
1354			break;
1355		case SBP2_STATUS_ILLEGAL_REQUEST:
1356		case SBP2_STATUS_VENDOR_DEPENDENT:
1357		default:
1358			result = DID_ERROR << 16;
1359			break;
1360		}
1361
1362		if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1363			result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1364							   orb->cmd->sense_buffer);
1365	} else {
1366		/*
1367		 * If the orb completes with status == NULL, something
1368		 * went wrong, typically a bus reset happened mid-orb
1369		 * or when sending the write (less likely).
1370		 */
1371		result = DID_BUS_BUSY << 16;
1372		sbp2_conditionally_block(base_orb->lu);
1373	}
1374
1375	dma_unmap_single(device->card->device, orb->base.request_bus,
1376			 sizeof(orb->request), DMA_TO_DEVICE);
1377	sbp2_unmap_scatterlist(device->card->device, orb);
1378
1379	orb->cmd->result = result;
1380	scsi_done(orb->cmd);
1381}
1382
1383static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1384		struct fw_device *device, struct sbp2_logical_unit *lu)
1385{
1386	struct scatterlist *sg = scsi_sglist(orb->cmd);
1387	int i, n;
1388
1389	n = scsi_dma_map(orb->cmd);
1390	if (n <= 0)
1391		goto fail;
1392
1393	/*
1394	 * Handle the special case where there is only one element in
1395	 * the scatter list by converting it to an immediate block
1396	 * request. This is also a workaround for broken devices such
1397	 * as the second generation iPod which doesn't support page
1398	 * tables.
1399	 */
1400	if (n == 1) {
1401		orb->request.data_descriptor.high =
1402			cpu_to_be32(lu->tgt->address_high);
1403		orb->request.data_descriptor.low  =
1404			cpu_to_be32(sg_dma_address(sg));
1405		orb->request.misc |=
1406			cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1407		return 0;
1408	}
1409
1410	for_each_sg(sg, sg, n, i) {
1411		orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1412		orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1413	}
1414
1415	orb->page_table_bus =
1416		dma_map_single(device->card->device, orb->page_table,
1417			       sizeof(orb->page_table), DMA_TO_DEVICE);
1418	if (dma_mapping_error(device->card->device, orb->page_table_bus))
1419		goto fail_page_table;
1420
1421	/*
1422	 * The data_descriptor pointer is the one case where we need
1423	 * to fill in the node ID part of the address.  All other
1424	 * pointers assume that the data referenced reside on the
1425	 * initiator (i.e. us), but data_descriptor can refer to data
1426	 * on other nodes so we need to put our ID in descriptor.high.
1427	 */
1428	orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1429	orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1430	orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1431					 COMMAND_ORB_DATA_SIZE(n));
1432
1433	return 0;
1434
1435 fail_page_table:
1436	scsi_dma_unmap(orb->cmd);
1437 fail:
1438	return -ENOMEM;
1439}
1440
1441/* SCSI stack integration */
1442
1443static int sbp2_scsi_queuecommand(struct Scsi_Host *shost,
1444				  struct scsi_cmnd *cmd)
1445{
1446	struct sbp2_logical_unit *lu = cmd->device->hostdata;
1447	struct fw_device *device = target_parent_device(lu->tgt);
1448	struct sbp2_command_orb *orb;
1449	int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1450
1451	orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1452	if (orb == NULL)
1453		return SCSI_MLQUEUE_HOST_BUSY;
1454
1455	/* Initialize rcode to something not RCODE_COMPLETE. */
1456	orb->base.rcode = -1;
1457	kref_init(&orb->base.kref);
1458	orb->cmd = cmd;
1459	orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1460	orb->request.misc = cpu_to_be32(
1461		COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1462		COMMAND_ORB_SPEED(device->max_speed) |
1463		COMMAND_ORB_NOTIFY);
1464
1465	if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1466		orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1467
1468	generation = device->generation;
1469	smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1470
1471	if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1472		goto out;
1473
1474	memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1475
1476	orb->base.callback = complete_command_orb;
1477	orb->base.request_bus =
1478		dma_map_single(device->card->device, &orb->request,
1479			       sizeof(orb->request), DMA_TO_DEVICE);
1480	if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1481		sbp2_unmap_scatterlist(device->card->device, orb);
1482		goto out;
1483	}
1484
1485	sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1486		      lu->command_block_agent_address + SBP2_ORB_POINTER);
1487	retval = 0;
1488 out:
1489	kref_put(&orb->base.kref, free_orb);
1490	return retval;
1491}
1492
1493static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1494{
1495	struct sbp2_logical_unit *lu = sdev->hostdata;
1496
1497	/* (Re-)Adding logical units via the SCSI stack is not supported. */
1498	if (!lu)
1499		return -ENOSYS;
1500
1501	sdev->allow_restart = 1;
1502
1503	/*
1504	 * SBP-2 does not require any alignment, but we set it anyway
1505	 * for compatibility with earlier versions of this driver.
1506	 */
1507	blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1508
1509	if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1510		sdev->inquiry_len = 36;
1511
1512	return 0;
1513}
1514
1515static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1516{
1517	struct sbp2_logical_unit *lu = sdev->hostdata;
1518
1519	sdev->use_10_for_rw = 1;
1520
1521	if (sbp2_param_exclusive_login) {
1522		sdev->manage_system_start_stop = 1;
1523		sdev->manage_runtime_start_stop = 1;
1524		sdev->manage_shutdown = 1;
1525	}
1526
1527	if (sdev->type == TYPE_ROM)
1528		sdev->use_10_for_ms = 1;
1529
1530	if (sdev->type == TYPE_DISK &&
1531	    lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1532		sdev->skip_ms_page_8 = 1;
1533
1534	if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1535		sdev->fix_capacity = 1;
1536
1537	if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1538		sdev->start_stop_pwr_cond = 1;
1539
1540	if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1541		blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1542
1543	return 0;
1544}
1545
1546/*
1547 * Called by scsi stack when something has really gone wrong.  Usually
1548 * called when a command has timed-out for some reason.
1549 */
1550static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1551{
1552	struct sbp2_logical_unit *lu = cmd->device->hostdata;
1553
1554	dev_notice(lu_dev(lu), "sbp2_scsi_abort\n");
1555	sbp2_agent_reset(lu);
1556	sbp2_cancel_orbs(lu);
1557
1558	return SUCCESS;
1559}
1560
1561/*
1562 * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1563 * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1564 *
1565 * This is the concatenation of target port identifier and logical unit
1566 * identifier as per SAM-2...SAM-4 annex A.
1567 */
1568static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1569			struct device_attribute *attr, char *buf)
1570{
1571	struct scsi_device *sdev = to_scsi_device(dev);
1572	struct sbp2_logical_unit *lu;
1573
1574	if (!sdev)
1575		return 0;
1576
1577	lu = sdev->hostdata;
1578
1579	return sprintf(buf, "%016llx:%06x:%04x\n",
1580			(unsigned long long)lu->tgt->guid,
1581			lu->tgt->directory_id, lu->lun);
1582}
1583
1584static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1585
1586static struct attribute *sbp2_scsi_sysfs_attrs[] = {
1587	&dev_attr_ieee1394_id.attr,
1588	NULL
1589};
1590
1591ATTRIBUTE_GROUPS(sbp2_scsi_sysfs);
1592
1593static const struct scsi_host_template scsi_driver_template = {
1594	.module			= THIS_MODULE,
1595	.name			= "SBP-2 IEEE-1394",
1596	.proc_name		= "sbp2",
1597	.queuecommand		= sbp2_scsi_queuecommand,
1598	.slave_alloc		= sbp2_scsi_slave_alloc,
1599	.slave_configure	= sbp2_scsi_slave_configure,
1600	.eh_abort_handler	= sbp2_scsi_abort,
1601	.this_id		= -1,
1602	.sg_tablesize		= SG_ALL,
1603	.max_segment_size	= SBP2_MAX_SEG_SIZE,
1604	.can_queue		= 1,
1605	.sdev_groups		= sbp2_scsi_sysfs_groups,
1606};
1607
1608MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1609MODULE_DESCRIPTION("SCSI over IEEE1394");
1610MODULE_LICENSE("GPL");
1611MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1612
1613/* Provide a module alias so root-on-sbp2 initrds don't break. */
1614MODULE_ALIAS("sbp2");
1615
1616static int __init sbp2_init(void)
1617{
1618	return driver_register(&sbp2_driver.driver);
1619}
1620
1621static void __exit sbp2_cleanup(void)
1622{
1623	driver_unregister(&sbp2_driver.driver);
1624}
1625
1626module_init(sbp2_init);
1627module_exit(sbp2_cleanup);
1628