firewire: cdev: extend transaction payload size check
[linux-2.6.git] / drivers / firewire / fw-sbp2.c
1 /*
2  * SBP2 driver (SCSI over IEEE1394)
3  *
4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 /*
22  * The basic structure of this driver is based on the old storage driver,
23  * drivers/ieee1394/sbp2.c, originally written by
24  *     James Goodwin <jamesg@filanet.com>
25  * with later contributions and ongoing maintenance from
26  *     Ben Collins <bcollins@debian.org>,
27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
28  * and many others.
29  */
30
31 #include <linux/blkdev.h>
32 #include <linux/bug.h>
33 #include <linux/delay.h>
34 #include <linux/device.h>
35 #include <linux/dma-mapping.h>
36 #include <linux/kernel.h>
37 #include <linux/mod_devicetable.h>
38 #include <linux/module.h>
39 #include <linux/moduleparam.h>
40 #include <linux/scatterlist.h>
41 #include <linux/string.h>
42 #include <linux/stringify.h>
43 #include <linux/timer.h>
44 #include <linux/workqueue.h>
45 #include <asm/system.h>
46
47 #include <scsi/scsi.h>
48 #include <scsi/scsi_cmnd.h>
49 #include <scsi/scsi_device.h>
50 #include <scsi/scsi_host.h>
51
52 #include "fw-device.h"
53 #include "fw-topology.h"
54 #include "fw-transaction.h"
55
56 /*
57  * So far only bridges from Oxford Semiconductor are known to support
58  * concurrent logins. Depending on firmware, four or two concurrent logins
59  * are possible on OXFW911 and newer Oxsemi bridges.
60  *
61  * Concurrent logins are useful together with cluster filesystems.
62  */
63 static int sbp2_param_exclusive_login = 1;
64 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
65 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
66                  "(default = Y, use N for concurrent initiators)");
67
68 /*
69  * Flags for firmware oddities
70  *
71  * - 128kB max transfer
72  *   Limit transfer size. Necessary for some old bridges.
73  *
74  * - 36 byte inquiry
75  *   When scsi_mod probes the device, let the inquiry command look like that
76  *   from MS Windows.
77  *
78  * - skip mode page 8
79  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
80  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
81  *
82  * - fix capacity
83  *   Tell sd_mod to correct the last sector number reported by read_capacity.
84  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
85  *   Don't use this with devices which don't have this bug.
86  *
87  * - delay inquiry
88  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
89  *
90  * - power condition
91  *   Set the power condition field in the START STOP UNIT commands sent by
92  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
93  *   Some disks need this to spin down or to resume properly.
94  *
95  * - override internal blacklist
96  *   Instead of adding to the built-in blacklist, use only the workarounds
97  *   specified in the module load parameter.
98  *   Useful if a blacklist entry interfered with a non-broken device.
99  */
100 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
101 #define SBP2_WORKAROUND_INQUIRY_36      0x2
102 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
103 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
104 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
105 #define SBP2_INQUIRY_DELAY              12
106 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
107 #define SBP2_WORKAROUND_OVERRIDE        0x100
108
109 static int sbp2_param_workarounds;
110 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
111 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
112         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
113         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
114         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
115         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
116         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
117         ", set power condition in start stop unit = "
118                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
119         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
120         ", or a combination)");
121
122 /* I don't know why the SCSI stack doesn't define something like this... */
123 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
124
125 static const char sbp2_driver_name[] = "sbp2";
126
127 /*
128  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
129  * and one struct scsi_device per sbp2_logical_unit.
130  */
131 struct sbp2_logical_unit {
132         struct sbp2_target *tgt;
133         struct list_head link;
134         struct fw_address_handler address_handler;
135         struct list_head orb_list;
136
137         u64 command_block_agent_address;
138         u16 lun;
139         int login_id;
140
141         /*
142          * The generation is updated once we've logged in or reconnected
143          * to the logical unit.  Thus, I/O to the device will automatically
144          * fail and get retried if it happens in a window where the device
145          * is not ready, e.g. after a bus reset but before we reconnect.
146          */
147         int generation;
148         int retries;
149         struct delayed_work work;
150         bool has_sdev;
151         bool blocked;
152 };
153
154 /*
155  * We create one struct sbp2_target per IEEE 1212 Unit Directory
156  * and one struct Scsi_Host per sbp2_target.
157  */
158 struct sbp2_target {
159         struct kref kref;
160         struct fw_unit *unit;
161         const char *bus_id;
162         struct list_head lu_list;
163
164         u64 management_agent_address;
165         u64 guid;
166         int directory_id;
167         int node_id;
168         int address_high;
169         unsigned int workarounds;
170         unsigned int mgt_orb_timeout;
171         unsigned int max_payload;
172
173         int dont_block; /* counter for each logical unit */
174         int blocked;    /* ditto */
175 };
176
177 /* Impossible login_id, to detect logout attempt before successful login */
178 #define INVALID_LOGIN_ID 0x10000
179
180 /*
181  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
182  * provided in the config rom. Most devices do provide a value, which
183  * we'll use for login management orbs, but with some sane limits.
184  */
185 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
186 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
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  * The default maximum s/g segment size of a FireWire controller is
194  * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
195  * be quadlet-aligned, we set the length limit to 0xffff & ~3.
196  */
197 #define SBP2_MAX_SEG_SIZE               0xfffc
198
199 /* Unit directory keys */
200 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
201 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
202 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
203 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
204
205 /* Management orb opcodes */
206 #define SBP2_LOGIN_REQUEST              0x0
207 #define SBP2_QUERY_LOGINS_REQUEST       0x1
208 #define SBP2_RECONNECT_REQUEST          0x3
209 #define SBP2_SET_PASSWORD_REQUEST       0x4
210 #define SBP2_LOGOUT_REQUEST             0x7
211 #define SBP2_ABORT_TASK_REQUEST         0xb
212 #define SBP2_ABORT_TASK_SET             0xc
213 #define SBP2_LOGICAL_UNIT_RESET         0xe
214 #define SBP2_TARGET_RESET_REQUEST       0xf
215
216 /* Offsets for command block agent registers */
217 #define SBP2_AGENT_STATE                0x00
218 #define SBP2_AGENT_RESET                0x04
219 #define SBP2_ORB_POINTER                0x08
220 #define SBP2_DOORBELL                   0x10
221 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
222
223 /* Status write response codes */
224 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
225 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
226 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
227 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
228
229 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
230 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
231 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
232 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
233 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
234 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
235 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
236 #define STATUS_GET_DATA(v)              ((v).data)
237
238 struct sbp2_status {
239         u32 status;
240         u32 orb_low;
241         u8 data[24];
242 };
243
244 struct sbp2_pointer {
245         __be32 high;
246         __be32 low;
247 };
248
249 struct sbp2_orb {
250         struct fw_transaction t;
251         struct kref kref;
252         dma_addr_t request_bus;
253         int rcode;
254         struct sbp2_pointer pointer;
255         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
256         struct list_head link;
257 };
258
259 #define MANAGEMENT_ORB_LUN(v)                   ((v))
260 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
261 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
262 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
263 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
264 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
265
266 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
267 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
268
269 struct sbp2_management_orb {
270         struct sbp2_orb base;
271         struct {
272                 struct sbp2_pointer password;
273                 struct sbp2_pointer response;
274                 __be32 misc;
275                 __be32 length;
276                 struct sbp2_pointer status_fifo;
277         } request;
278         __be32 response[4];
279         dma_addr_t response_bus;
280         struct completion done;
281         struct sbp2_status status;
282 };
283
284 struct sbp2_login_response {
285         __be32 misc;
286         struct sbp2_pointer command_block_agent;
287         __be32 reconnect_hold;
288 };
289 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
290 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
291 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
292 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
293 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
294 #define COMMAND_ORB_DIRECTION           ((1) << 27)
295 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
296 #define COMMAND_ORB_NOTIFY              ((1) << 31)
297
298 struct sbp2_command_orb {
299         struct sbp2_orb base;
300         struct {
301                 struct sbp2_pointer next;
302                 struct sbp2_pointer data_descriptor;
303                 __be32 misc;
304                 u8 command_block[12];
305         } request;
306         struct scsi_cmnd *cmd;
307         scsi_done_fn_t done;
308         struct sbp2_logical_unit *lu;
309
310         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
311         dma_addr_t page_table_bus;
312 };
313
314 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
315 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
316
317 /*
318  * List of devices with known bugs.
319  *
320  * The firmware_revision field, masked with 0xffff00, is the best
321  * indicator for the type of bridge chip of a device.  It yields a few
322  * false positives but this did not break correctly behaving devices
323  * so far.
324  */
325 static const struct {
326         u32 firmware_revision;
327         u32 model;
328         unsigned int workarounds;
329 } sbp2_workarounds_table[] = {
330         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
331                 .firmware_revision      = 0x002800,
332                 .model                  = 0x001010,
333                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
334                                           SBP2_WORKAROUND_MODE_SENSE_8 |
335                                           SBP2_WORKAROUND_POWER_CONDITION,
336         },
337         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
338                 .firmware_revision      = 0x002800,
339                 .model                  = 0x000000,
340                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY |
341                                           SBP2_WORKAROUND_POWER_CONDITION,
342         },
343         /* Initio bridges, actually only needed for some older ones */ {
344                 .firmware_revision      = 0x000200,
345                 .model                  = SBP2_ROM_VALUE_WILDCARD,
346                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
347         },
348         /* PL-3507 bridge with Prolific firmware */ {
349                 .firmware_revision      = 0x012800,
350                 .model                  = SBP2_ROM_VALUE_WILDCARD,
351                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
352         },
353         /* Symbios bridge */ {
354                 .firmware_revision      = 0xa0b800,
355                 .model                  = SBP2_ROM_VALUE_WILDCARD,
356                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
357         },
358         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
359                 .firmware_revision      = 0x002600,
360                 .model                  = SBP2_ROM_VALUE_WILDCARD,
361                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
362         },
363         /*
364          * iPod 2nd generation: needs 128k max transfer size workaround
365          * iPod 3rd generation: needs fix capacity workaround
366          */
367         {
368                 .firmware_revision      = 0x0a2700,
369                 .model                  = 0x000000,
370                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
371                                           SBP2_WORKAROUND_FIX_CAPACITY,
372         },
373         /* iPod 4th generation */ {
374                 .firmware_revision      = 0x0a2700,
375                 .model                  = 0x000021,
376                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
377         },
378         /* iPod mini */ {
379                 .firmware_revision      = 0x0a2700,
380                 .model                  = 0x000022,
381                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
382         },
383         /* iPod mini */ {
384                 .firmware_revision      = 0x0a2700,
385                 .model                  = 0x000023,
386                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
387         },
388         /* iPod Photo */ {
389                 .firmware_revision      = 0x0a2700,
390                 .model                  = 0x00007e,
391                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
392         }
393 };
394
395 static void free_orb(struct kref *kref)
396 {
397         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
398
399         kfree(orb);
400 }
401
402 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
403                               int tcode, int destination, int source,
404                               int generation, int speed,
405                               unsigned long long offset,
406                               void *payload, size_t length, void *callback_data)
407 {
408         struct sbp2_logical_unit *lu = callback_data;
409         struct sbp2_orb *orb;
410         struct sbp2_status status;
411         size_t header_size;
412         unsigned long flags;
413
414         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
415             length == 0 || length > sizeof(status)) {
416                 fw_send_response(card, request, RCODE_TYPE_ERROR);
417                 return;
418         }
419
420         header_size = min(length, 2 * sizeof(u32));
421         fw_memcpy_from_be32(&status, payload, header_size);
422         if (length > header_size)
423                 memcpy(status.data, payload + 8, length - header_size);
424         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
425                 fw_notify("non-orb related status write, not handled\n");
426                 fw_send_response(card, request, RCODE_COMPLETE);
427                 return;
428         }
429
430         /* Lookup the orb corresponding to this status write. */
431         spin_lock_irqsave(&card->lock, flags);
432         list_for_each_entry(orb, &lu->orb_list, link) {
433                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
434                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
435                         orb->rcode = RCODE_COMPLETE;
436                         list_del(&orb->link);
437                         break;
438                 }
439         }
440         spin_unlock_irqrestore(&card->lock, flags);
441
442         if (&orb->link != &lu->orb_list)
443                 orb->callback(orb, &status);
444         else
445                 fw_error("status write for unknown orb\n");
446
447         kref_put(&orb->kref, free_orb);
448
449         fw_send_response(card, request, RCODE_COMPLETE);
450 }
451
452 static void complete_transaction(struct fw_card *card, int rcode,
453                                  void *payload, size_t length, void *data)
454 {
455         struct sbp2_orb *orb = data;
456         unsigned long flags;
457
458         /*
459          * This is a little tricky.  We can get the status write for
460          * the orb before we get this callback.  The status write
461          * handler above will assume the orb pointer transaction was
462          * successful and set the rcode to RCODE_COMPLETE for the orb.
463          * So this callback only sets the rcode if it hasn't already
464          * been set and only does the cleanup if the transaction
465          * failed and we didn't already get a status write.
466          */
467         spin_lock_irqsave(&card->lock, flags);
468
469         if (orb->rcode == -1)
470                 orb->rcode = rcode;
471         if (orb->rcode != RCODE_COMPLETE) {
472                 list_del(&orb->link);
473                 spin_unlock_irqrestore(&card->lock, flags);
474                 orb->callback(orb, NULL);
475         } else {
476                 spin_unlock_irqrestore(&card->lock, flags);
477         }
478
479         kref_put(&orb->kref, free_orb);
480 }
481
482 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
483                           int node_id, int generation, u64 offset)
484 {
485         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
486         unsigned long flags;
487
488         orb->pointer.high = 0;
489         orb->pointer.low = cpu_to_be32(orb->request_bus);
490
491         spin_lock_irqsave(&device->card->lock, flags);
492         list_add_tail(&orb->link, &lu->orb_list);
493         spin_unlock_irqrestore(&device->card->lock, flags);
494
495         /* Take a ref for the orb list and for the transaction callback. */
496         kref_get(&orb->kref);
497         kref_get(&orb->kref);
498
499         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
500                         node_id, generation, device->max_speed, offset,
501                         &orb->pointer, sizeof(orb->pointer),
502                         complete_transaction, orb);
503 }
504
505 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
506 {
507         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
508         struct sbp2_orb *orb, *next;
509         struct list_head list;
510         unsigned long flags;
511         int retval = -ENOENT;
512
513         INIT_LIST_HEAD(&list);
514         spin_lock_irqsave(&device->card->lock, flags);
515         list_splice_init(&lu->orb_list, &list);
516         spin_unlock_irqrestore(&device->card->lock, flags);
517
518         list_for_each_entry_safe(orb, next, &list, link) {
519                 retval = 0;
520                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
521                         continue;
522
523                 orb->rcode = RCODE_CANCELLED;
524                 orb->callback(orb, NULL);
525         }
526
527         return retval;
528 }
529
530 static void complete_management_orb(struct sbp2_orb *base_orb,
531                                     struct sbp2_status *status)
532 {
533         struct sbp2_management_orb *orb =
534                 container_of(base_orb, struct sbp2_management_orb, base);
535
536         if (status)
537                 memcpy(&orb->status, status, sizeof(*status));
538         complete(&orb->done);
539 }
540
541 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
542                                     int generation, int function,
543                                     int lun_or_login_id, void *response)
544 {
545         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
546         struct sbp2_management_orb *orb;
547         unsigned int timeout;
548         int retval = -ENOMEM;
549
550         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
551                 return 0;
552
553         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
554         if (orb == NULL)
555                 return -ENOMEM;
556
557         kref_init(&orb->base.kref);
558         orb->response_bus =
559                 dma_map_single(device->card->device, &orb->response,
560                                sizeof(orb->response), DMA_FROM_DEVICE);
561         if (dma_mapping_error(device->card->device, orb->response_bus))
562                 goto fail_mapping_response;
563
564         orb->request.response.high = 0;
565         orb->request.response.low  = cpu_to_be32(orb->response_bus);
566
567         orb->request.misc = cpu_to_be32(
568                 MANAGEMENT_ORB_NOTIFY |
569                 MANAGEMENT_ORB_FUNCTION(function) |
570                 MANAGEMENT_ORB_LUN(lun_or_login_id));
571         orb->request.length = cpu_to_be32(
572                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
573
574         orb->request.status_fifo.high =
575                 cpu_to_be32(lu->address_handler.offset >> 32);
576         orb->request.status_fifo.low  =
577                 cpu_to_be32(lu->address_handler.offset);
578
579         if (function == SBP2_LOGIN_REQUEST) {
580                 /* Ask for 2^2 == 4 seconds reconnect grace period */
581                 orb->request.misc |= cpu_to_be32(
582                         MANAGEMENT_ORB_RECONNECT(2) |
583                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
584                 timeout = lu->tgt->mgt_orb_timeout;
585         } else {
586                 timeout = SBP2_ORB_TIMEOUT;
587         }
588
589         init_completion(&orb->done);
590         orb->base.callback = complete_management_orb;
591
592         orb->base.request_bus =
593                 dma_map_single(device->card->device, &orb->request,
594                                sizeof(orb->request), DMA_TO_DEVICE);
595         if (dma_mapping_error(device->card->device, orb->base.request_bus))
596                 goto fail_mapping_request;
597
598         sbp2_send_orb(&orb->base, lu, node_id, generation,
599                       lu->tgt->management_agent_address);
600
601         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
602
603         retval = -EIO;
604         if (sbp2_cancel_orbs(lu) == 0) {
605                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
606                          lu->tgt->bus_id, orb->base.rcode);
607                 goto out;
608         }
609
610         if (orb->base.rcode != RCODE_COMPLETE) {
611                 fw_error("%s: management write failed, rcode 0x%02x\n",
612                          lu->tgt->bus_id, orb->base.rcode);
613                 goto out;
614         }
615
616         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
617             STATUS_GET_SBP_STATUS(orb->status) != 0) {
618                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
619                          STATUS_GET_RESPONSE(orb->status),
620                          STATUS_GET_SBP_STATUS(orb->status));
621                 goto out;
622         }
623
624         retval = 0;
625  out:
626         dma_unmap_single(device->card->device, orb->base.request_bus,
627                          sizeof(orb->request), DMA_TO_DEVICE);
628  fail_mapping_request:
629         dma_unmap_single(device->card->device, orb->response_bus,
630                          sizeof(orb->response), DMA_FROM_DEVICE);
631  fail_mapping_response:
632         if (response)
633                 memcpy(response, orb->response, sizeof(orb->response));
634         kref_put(&orb->base.kref, free_orb);
635
636         return retval;
637 }
638
639 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
640 {
641         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
642         __be32 d = 0;
643
644         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
645                            lu->tgt->node_id, lu->generation, device->max_speed,
646                            lu->command_block_agent_address + SBP2_AGENT_RESET,
647                            &d, sizeof(d));
648 }
649
650 static void complete_agent_reset_write_no_wait(struct fw_card *card,
651                 int rcode, void *payload, size_t length, void *data)
652 {
653         kfree(data);
654 }
655
656 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
657 {
658         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
659         struct fw_transaction *t;
660         static __be32 d;
661
662         t = kmalloc(sizeof(*t), GFP_ATOMIC);
663         if (t == NULL)
664                 return;
665
666         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
667                         lu->tgt->node_id, lu->generation, device->max_speed,
668                         lu->command_block_agent_address + SBP2_AGENT_RESET,
669                         &d, sizeof(d), complete_agent_reset_write_no_wait, t);
670 }
671
672 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
673 {
674         /*
675          * We may access dont_block without taking card->lock here:
676          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
677          * are currently serialized against each other.
678          * And a wrong result in sbp2_conditionally_block()'s access of
679          * dont_block is rather harmless, it simply misses its first chance.
680          */
681         --lu->tgt->dont_block;
682 }
683
684 /*
685  * Blocks lu->tgt if all of the following conditions are met:
686  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
687  *     logical units have been finished (indicated by dont_block == 0).
688  *   - lu->generation is stale.
689  *
690  * Note, scsi_block_requests() must be called while holding card->lock,
691  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
692  * unblock the target.
693  */
694 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
695 {
696         struct sbp2_target *tgt = lu->tgt;
697         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
698         struct Scsi_Host *shost =
699                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
700         unsigned long flags;
701
702         spin_lock_irqsave(&card->lock, flags);
703         if (!tgt->dont_block && !lu->blocked &&
704             lu->generation != card->generation) {
705                 lu->blocked = true;
706                 if (++tgt->blocked == 1)
707                         scsi_block_requests(shost);
708         }
709         spin_unlock_irqrestore(&card->lock, flags);
710 }
711
712 /*
713  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
714  * Note, it is harmless to run scsi_unblock_requests() outside the
715  * card->lock protected section.  On the other hand, running it inside
716  * the section might clash with shost->host_lock.
717  */
718 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
719 {
720         struct sbp2_target *tgt = lu->tgt;
721         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
722         struct Scsi_Host *shost =
723                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
724         unsigned long flags;
725         bool unblock = false;
726
727         spin_lock_irqsave(&card->lock, flags);
728         if (lu->blocked && lu->generation == card->generation) {
729                 lu->blocked = false;
730                 unblock = --tgt->blocked == 0;
731         }
732         spin_unlock_irqrestore(&card->lock, flags);
733
734         if (unblock)
735                 scsi_unblock_requests(shost);
736 }
737
738 /*
739  * Prevents future blocking of tgt and unblocks it.
740  * Note, it is harmless to run scsi_unblock_requests() outside the
741  * card->lock protected section.  On the other hand, running it inside
742  * the section might clash with shost->host_lock.
743  */
744 static void sbp2_unblock(struct sbp2_target *tgt)
745 {
746         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
747         struct Scsi_Host *shost =
748                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
749         unsigned long flags;
750
751         spin_lock_irqsave(&card->lock, flags);
752         ++tgt->dont_block;
753         spin_unlock_irqrestore(&card->lock, flags);
754
755         scsi_unblock_requests(shost);
756 }
757
758 static 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 static void sbp2_release_target(struct kref *kref)
770 {
771         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
772         struct sbp2_logical_unit *lu, *next;
773         struct Scsi_Host *shost =
774                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
775         struct scsi_device *sdev;
776         struct fw_device *device = fw_device(tgt->unit->device.parent);
777
778         /* prevent deadlocks */
779         sbp2_unblock(tgt);
780
781         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
782                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
783                 if (sdev) {
784                         scsi_remove_device(sdev);
785                         scsi_device_put(sdev);
786                 }
787                 if (lu->login_id != INVALID_LOGIN_ID) {
788                         int generation, node_id;
789                         /*
790                          * tgt->node_id may be obsolete here if we failed
791                          * during initial login or after a bus reset where
792                          * the topology changed.
793                          */
794                         generation = device->generation;
795                         smp_rmb(); /* node_id vs. generation */
796                         node_id    = device->node_id;
797                         sbp2_send_management_orb(lu, node_id, generation,
798                                                  SBP2_LOGOUT_REQUEST,
799                                                  lu->login_id, NULL);
800                 }
801                 fw_core_remove_address_handler(&lu->address_handler);
802                 list_del(&lu->link);
803                 kfree(lu);
804         }
805         scsi_remove_host(shost);
806         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
807
808         fw_unit_put(tgt->unit);
809         scsi_host_put(shost);
810         fw_device_put(device);
811 }
812
813 static struct workqueue_struct *sbp2_wq;
814
815 static void sbp2_target_put(struct sbp2_target *tgt)
816 {
817         kref_put(&tgt->kref, sbp2_release_target);
818 }
819
820 /*
821  * Always get the target's kref when scheduling work on one its units.
822  * Each workqueue job is responsible to call sbp2_target_put() upon return.
823  */
824 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
825 {
826         kref_get(&lu->tgt->kref);
827         if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
828                 sbp2_target_put(lu->tgt);
829 }
830
831 /*
832  * Write retransmit retry values into the BUSY_TIMEOUT register.
833  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
834  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
835  *   saner value after logging into the device.
836  * - The dual-phase retry protocol is optional to implement, and if not
837  *   supported, writes to the dual-phase portion of the register will be
838  *   ignored. We try to write the original 1394-1995 default here.
839  * - In the case of devices that are also SBP-3-compliant, all writes are
840  *   ignored, as the register is read-only, but contains single-phase retry of
841  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
842  *   write attempt is safe and yields more consistent behavior for all devices.
843  *
844  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
845  * and section 6.4 of the SBP-3 spec for further details.
846  */
847 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
848 {
849         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
850         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
851
852         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
853                            lu->tgt->node_id, lu->generation, device->max_speed,
854                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
855                            &d, sizeof(d));
856 }
857
858 static void sbp2_reconnect(struct work_struct *work);
859
860 static void sbp2_login(struct work_struct *work)
861 {
862         struct sbp2_logical_unit *lu =
863                 container_of(work, struct sbp2_logical_unit, work.work);
864         struct sbp2_target *tgt = lu->tgt;
865         struct fw_device *device = fw_device(tgt->unit->device.parent);
866         struct Scsi_Host *shost;
867         struct scsi_device *sdev;
868         struct sbp2_login_response response;
869         int generation, node_id, local_node_id;
870
871         if (fw_device_is_shutdown(device))
872                 goto out;
873
874         generation    = device->generation;
875         smp_rmb();    /* node IDs must not be older than generation */
876         node_id       = device->node_id;
877         local_node_id = device->card->node_id;
878
879         /* If this is a re-login attempt, log out, or we might be rejected. */
880         if (lu->has_sdev)
881                 sbp2_send_management_orb(lu, device->node_id, generation,
882                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
883
884         if (sbp2_send_management_orb(lu, node_id, generation,
885                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
886                 if (lu->retries++ < 5) {
887                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
888                 } else {
889                         fw_error("%s: failed to login to LUN %04x\n",
890                                  tgt->bus_id, lu->lun);
891                         /* Let any waiting I/O fail from now on. */
892                         sbp2_unblock(lu->tgt);
893                 }
894                 goto out;
895         }
896
897         tgt->node_id      = node_id;
898         tgt->address_high = local_node_id << 16;
899         smp_wmb();        /* node IDs must not be older than generation */
900         lu->generation    = generation;
901
902         lu->command_block_agent_address =
903                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
904                       << 32) | be32_to_cpu(response.command_block_agent.low);
905         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
906
907         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
908                   tgt->bus_id, lu->lun, lu->retries);
909
910         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
911         sbp2_set_busy_timeout(lu);
912
913         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
914         sbp2_agent_reset(lu);
915
916         /* This was a re-login. */
917         if (lu->has_sdev) {
918                 sbp2_cancel_orbs(lu);
919                 sbp2_conditionally_unblock(lu);
920                 goto out;
921         }
922
923         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
924                 ssleep(SBP2_INQUIRY_DELAY);
925
926         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
927         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
928         /*
929          * FIXME:  We are unable to perform reconnects while in sbp2_login().
930          * Therefore __scsi_add_device() will get into trouble if a bus reset
931          * happens in parallel.  It will either fail or leave us with an
932          * unusable sdev.  As a workaround we check for this and retry the
933          * whole login and SCSI probing.
934          */
935
936         /* Reported error during __scsi_add_device() */
937         if (IS_ERR(sdev))
938                 goto out_logout_login;
939
940         /* Unreported error during __scsi_add_device() */
941         smp_rmb(); /* get current card generation */
942         if (generation != device->card->generation) {
943                 scsi_remove_device(sdev);
944                 scsi_device_put(sdev);
945                 goto out_logout_login;
946         }
947
948         /* No error during __scsi_add_device() */
949         lu->has_sdev = true;
950         scsi_device_put(sdev);
951         sbp2_allow_block(lu);
952         goto out;
953
954  out_logout_login:
955         smp_rmb(); /* generation may have changed */
956         generation = device->generation;
957         smp_rmb(); /* node_id must not be older than generation */
958
959         sbp2_send_management_orb(lu, device->node_id, generation,
960                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
961         /*
962          * If a bus reset happened, sbp2_update will have requeued
963          * lu->work already.  Reset the work from reconnect to login.
964          */
965         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
966  out:
967         sbp2_target_put(tgt);
968 }
969
970 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
971 {
972         struct sbp2_logical_unit *lu;
973
974         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
975         if (!lu)
976                 return -ENOMEM;
977
978         lu->address_handler.length           = 0x100;
979         lu->address_handler.address_callback = sbp2_status_write;
980         lu->address_handler.callback_data    = lu;
981
982         if (fw_core_add_address_handler(&lu->address_handler,
983                                         &fw_high_memory_region) < 0) {
984                 kfree(lu);
985                 return -ENOMEM;
986         }
987
988         lu->tgt      = tgt;
989         lu->lun      = lun_entry & 0xffff;
990         lu->login_id = INVALID_LOGIN_ID;
991         lu->retries  = 0;
992         lu->has_sdev = false;
993         lu->blocked  = false;
994         ++tgt->dont_block;
995         INIT_LIST_HEAD(&lu->orb_list);
996         INIT_DELAYED_WORK(&lu->work, sbp2_login);
997
998         list_add_tail(&lu->link, &tgt->lu_list);
999         return 0;
1000 }
1001
1002 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
1003 {
1004         struct fw_csr_iterator ci;
1005         int key, value;
1006
1007         fw_csr_iterator_init(&ci, directory);
1008         while (fw_csr_iterator_next(&ci, &key, &value))
1009                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1010                     sbp2_add_logical_unit(tgt, value) < 0)
1011                         return -ENOMEM;
1012         return 0;
1013 }
1014
1015 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
1016                               u32 *model, u32 *firmware_revision)
1017 {
1018         struct fw_csr_iterator ci;
1019         int key, value;
1020         unsigned int timeout;
1021
1022         fw_csr_iterator_init(&ci, directory);
1023         while (fw_csr_iterator_next(&ci, &key, &value)) {
1024                 switch (key) {
1025
1026                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1027                         tgt->management_agent_address =
1028                                         CSR_REGISTER_BASE + 4 * value;
1029                         break;
1030
1031                 case CSR_DIRECTORY_ID:
1032                         tgt->directory_id = value;
1033                         break;
1034
1035                 case CSR_MODEL:
1036                         *model = value;
1037                         break;
1038
1039                 case SBP2_CSR_FIRMWARE_REVISION:
1040                         *firmware_revision = value;
1041                         break;
1042
1043                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1044                         /* the timeout value is stored in 500ms units */
1045                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1046                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1047                         tgt->mgt_orb_timeout =
1048                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1049
1050                         if (timeout > tgt->mgt_orb_timeout)
1051                                 fw_notify("%s: config rom contains %ds "
1052                                           "management ORB timeout, limiting "
1053                                           "to %ds\n", tgt->bus_id,
1054                                           timeout / 1000,
1055                                           tgt->mgt_orb_timeout / 1000);
1056                         break;
1057
1058                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1059                         if (sbp2_add_logical_unit(tgt, value) < 0)
1060                                 return -ENOMEM;
1061                         break;
1062
1063                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1064                         /* Adjust for the increment in the iterator */
1065                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1066                                 return -ENOMEM;
1067                         break;
1068                 }
1069         }
1070         return 0;
1071 }
1072
1073 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1074                                   u32 firmware_revision)
1075 {
1076         int i;
1077         unsigned int w = sbp2_param_workarounds;
1078
1079         if (w)
1080                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1081                           "if you need the workarounds parameter for %s\n",
1082                           tgt->bus_id);
1083
1084         if (w & SBP2_WORKAROUND_OVERRIDE)
1085                 goto out;
1086
1087         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1088
1089                 if (sbp2_workarounds_table[i].firmware_revision !=
1090                     (firmware_revision & 0xffffff00))
1091                         continue;
1092
1093                 if (sbp2_workarounds_table[i].model != model &&
1094                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1095                         continue;
1096
1097                 w |= sbp2_workarounds_table[i].workarounds;
1098                 break;
1099         }
1100  out:
1101         if (w)
1102                 fw_notify("Workarounds for %s: 0x%x "
1103                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1104                           tgt->bus_id, w, firmware_revision, model);
1105         tgt->workarounds = w;
1106 }
1107
1108 static struct scsi_host_template scsi_driver_template;
1109
1110 static int sbp2_probe(struct device *dev)
1111 {
1112         struct fw_unit *unit = fw_unit(dev);
1113         struct fw_device *device = fw_device(unit->device.parent);
1114         struct sbp2_target *tgt;
1115         struct sbp2_logical_unit *lu;
1116         struct Scsi_Host *shost;
1117         u32 model, firmware_revision;
1118
1119         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1120                 BUG_ON(dma_set_max_seg_size(device->card->device,
1121                                             SBP2_MAX_SEG_SIZE));
1122
1123         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1124         if (shost == NULL)
1125                 return -ENOMEM;
1126
1127         tgt = (struct sbp2_target *)shost->hostdata;
1128         unit->device.driver_data = tgt;
1129         tgt->unit = unit;
1130         kref_init(&tgt->kref);
1131         INIT_LIST_HEAD(&tgt->lu_list);
1132         tgt->bus_id = dev_name(&unit->device);
1133         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1134
1135         if (fw_device_enable_phys_dma(device) < 0)
1136                 goto fail_shost_put;
1137
1138         if (scsi_add_host(shost, &unit->device) < 0)
1139                 goto fail_shost_put;
1140
1141         fw_device_get(device);
1142         fw_unit_get(unit);
1143
1144         /* implicit directory ID */
1145         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1146                              + CSR_CONFIG_ROM) & 0xffffff;
1147
1148         firmware_revision = SBP2_ROM_VALUE_MISSING;
1149         model             = SBP2_ROM_VALUE_MISSING;
1150
1151         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1152                                &firmware_revision) < 0)
1153                 goto fail_tgt_put;
1154
1155         sbp2_init_workarounds(tgt, model, firmware_revision);
1156
1157         /*
1158          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1159          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1160          * specifies the max payload size as 2 ^ (max_payload + 2), so
1161          * if we set this to max_speed + 7, we get the right value.
1162          */
1163         tgt->max_payload = min(device->max_speed + 7, 10U);
1164         tgt->max_payload = min(tgt->max_payload, device->card->max_receive - 1);
1165
1166         /* Do the login in a workqueue so we can easily reschedule retries. */
1167         list_for_each_entry(lu, &tgt->lu_list, link)
1168                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1169         return 0;
1170
1171  fail_tgt_put:
1172         sbp2_target_put(tgt);
1173         return -ENOMEM;
1174
1175  fail_shost_put:
1176         scsi_host_put(shost);
1177         return -ENOMEM;
1178 }
1179
1180 static int sbp2_remove(struct device *dev)
1181 {
1182         struct fw_unit *unit = fw_unit(dev);
1183         struct sbp2_target *tgt = unit->device.driver_data;
1184
1185         sbp2_target_put(tgt);
1186         return 0;
1187 }
1188
1189 static void sbp2_reconnect(struct work_struct *work)
1190 {
1191         struct sbp2_logical_unit *lu =
1192                 container_of(work, struct sbp2_logical_unit, work.work);
1193         struct sbp2_target *tgt = lu->tgt;
1194         struct fw_device *device = fw_device(tgt->unit->device.parent);
1195         int generation, node_id, local_node_id;
1196
1197         if (fw_device_is_shutdown(device))
1198                 goto out;
1199
1200         generation    = device->generation;
1201         smp_rmb();    /* node IDs must not be older than generation */
1202         node_id       = device->node_id;
1203         local_node_id = device->card->node_id;
1204
1205         if (sbp2_send_management_orb(lu, node_id, generation,
1206                                      SBP2_RECONNECT_REQUEST,
1207                                      lu->login_id, NULL) < 0) {
1208                 /*
1209                  * If reconnect was impossible even though we are in the
1210                  * current generation, fall back and try to log in again.
1211                  *
1212                  * We could check for "Function rejected" status, but
1213                  * looking at the bus generation as simpler and more general.
1214                  */
1215                 smp_rmb(); /* get current card generation */
1216                 if (generation == device->card->generation ||
1217                     lu->retries++ >= 5) {
1218                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1219                         lu->retries = 0;
1220                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1221                 }
1222                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1223                 goto out;
1224         }
1225
1226         tgt->node_id      = node_id;
1227         tgt->address_high = local_node_id << 16;
1228         smp_wmb();        /* node IDs must not be older than generation */
1229         lu->generation    = generation;
1230
1231         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1232                   tgt->bus_id, lu->lun, lu->retries);
1233
1234         sbp2_agent_reset(lu);
1235         sbp2_cancel_orbs(lu);
1236         sbp2_conditionally_unblock(lu);
1237  out:
1238         sbp2_target_put(tgt);
1239 }
1240
1241 static void sbp2_update(struct fw_unit *unit)
1242 {
1243         struct sbp2_target *tgt = unit->device.driver_data;
1244         struct sbp2_logical_unit *lu;
1245
1246         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1247
1248         /*
1249          * Fw-core serializes sbp2_update() against sbp2_remove().
1250          * Iteration over tgt->lu_list is therefore safe here.
1251          */
1252         list_for_each_entry(lu, &tgt->lu_list, link) {
1253                 sbp2_conditionally_block(lu);
1254                 lu->retries = 0;
1255                 sbp2_queue_work(lu, 0);
1256         }
1257 }
1258
1259 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1260 #define SBP2_SW_VERSION_ENTRY   0x00010483
1261
1262 static const struct fw_device_id sbp2_id_table[] = {
1263         {
1264                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1265                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1266                 .version      = SBP2_SW_VERSION_ENTRY,
1267         },
1268         { }
1269 };
1270
1271 static struct fw_driver sbp2_driver = {
1272         .driver   = {
1273                 .owner  = THIS_MODULE,
1274                 .name   = sbp2_driver_name,
1275                 .bus    = &fw_bus_type,
1276                 .probe  = sbp2_probe,
1277                 .remove = sbp2_remove,
1278         },
1279         .update   = sbp2_update,
1280         .id_table = sbp2_id_table,
1281 };
1282
1283 static void sbp2_unmap_scatterlist(struct device *card_device,
1284                                    struct sbp2_command_orb *orb)
1285 {
1286         if (scsi_sg_count(orb->cmd))
1287                 dma_unmap_sg(card_device, scsi_sglist(orb->cmd),
1288                              scsi_sg_count(orb->cmd),
1289                              orb->cmd->sc_data_direction);
1290
1291         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1292                 dma_unmap_single(card_device, orb->page_table_bus,
1293                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1294 }
1295
1296 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1297 {
1298         int sam_status;
1299
1300         sense_data[0] = 0x70;
1301         sense_data[1] = 0x0;
1302         sense_data[2] = sbp2_status[1];
1303         sense_data[3] = sbp2_status[4];
1304         sense_data[4] = sbp2_status[5];
1305         sense_data[5] = sbp2_status[6];
1306         sense_data[6] = sbp2_status[7];
1307         sense_data[7] = 10;
1308         sense_data[8] = sbp2_status[8];
1309         sense_data[9] = sbp2_status[9];
1310         sense_data[10] = sbp2_status[10];
1311         sense_data[11] = sbp2_status[11];
1312         sense_data[12] = sbp2_status[2];
1313         sense_data[13] = sbp2_status[3];
1314         sense_data[14] = sbp2_status[12];
1315         sense_data[15] = sbp2_status[13];
1316
1317         sam_status = sbp2_status[0] & 0x3f;
1318
1319         switch (sam_status) {
1320         case SAM_STAT_GOOD:
1321         case SAM_STAT_CHECK_CONDITION:
1322         case SAM_STAT_CONDITION_MET:
1323         case SAM_STAT_BUSY:
1324         case SAM_STAT_RESERVATION_CONFLICT:
1325         case SAM_STAT_COMMAND_TERMINATED:
1326                 return DID_OK << 16 | sam_status;
1327
1328         default:
1329                 return DID_ERROR << 16;
1330         }
1331 }
1332
1333 static void complete_command_orb(struct sbp2_orb *base_orb,
1334                                  struct sbp2_status *status)
1335 {
1336         struct sbp2_command_orb *orb =
1337                 container_of(base_orb, struct sbp2_command_orb, base);
1338         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1339         int result;
1340
1341         if (status != NULL) {
1342                 if (STATUS_GET_DEAD(*status))
1343                         sbp2_agent_reset_no_wait(orb->lu);
1344
1345                 switch (STATUS_GET_RESPONSE(*status)) {
1346                 case SBP2_STATUS_REQUEST_COMPLETE:
1347                         result = DID_OK << 16;
1348                         break;
1349                 case SBP2_STATUS_TRANSPORT_FAILURE:
1350                         result = DID_BUS_BUSY << 16;
1351                         break;
1352                 case SBP2_STATUS_ILLEGAL_REQUEST:
1353                 case SBP2_STATUS_VENDOR_DEPENDENT:
1354                 default:
1355                         result = DID_ERROR << 16;
1356                         break;
1357                 }
1358
1359                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1360                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1361                                                            orb->cmd->sense_buffer);
1362         } else {
1363                 /*
1364                  * If the orb completes with status == NULL, something
1365                  * went wrong, typically a bus reset happened mid-orb
1366                  * or when sending the write (less likely).
1367                  */
1368                 result = DID_BUS_BUSY << 16;
1369                 sbp2_conditionally_block(orb->lu);
1370         }
1371
1372         dma_unmap_single(device->card->device, orb->base.request_bus,
1373                          sizeof(orb->request), DMA_TO_DEVICE);
1374         sbp2_unmap_scatterlist(device->card->device, orb);
1375
1376         orb->cmd->result = result;
1377         orb->done(orb->cmd);
1378 }
1379
1380 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1381                 struct fw_device *device, struct sbp2_logical_unit *lu)
1382 {
1383         struct scatterlist *sg = scsi_sglist(orb->cmd);
1384         int i, n;
1385
1386         n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1387                        orb->cmd->sc_data_direction);
1388         if (n == 0)
1389                 goto fail;
1390
1391         /*
1392          * Handle the special case where there is only one element in
1393          * the scatter list by converting it to an immediate block
1394          * request. This is also a workaround for broken devices such
1395          * as the second generation iPod which doesn't support page
1396          * tables.
1397          */
1398         if (n == 1) {
1399                 orb->request.data_descriptor.high =
1400                         cpu_to_be32(lu->tgt->address_high);
1401                 orb->request.data_descriptor.low  =
1402                         cpu_to_be32(sg_dma_address(sg));
1403                 orb->request.misc |=
1404                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1405                 return 0;
1406         }
1407
1408         for_each_sg(sg, sg, n, i) {
1409                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1410                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1411         }
1412
1413         orb->page_table_bus =
1414                 dma_map_single(device->card->device, orb->page_table,
1415                                sizeof(orb->page_table), DMA_TO_DEVICE);
1416         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1417                 goto fail_page_table;
1418
1419         /*
1420          * The data_descriptor pointer is the one case where we need
1421          * to fill in the node ID part of the address.  All other
1422          * pointers assume that the data referenced reside on the
1423          * initiator (i.e. us), but data_descriptor can refer to data
1424          * on other nodes so we need to put our ID in descriptor.high.
1425          */
1426         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1427         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1428         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1429                                          COMMAND_ORB_DATA_SIZE(n));
1430
1431         return 0;
1432
1433  fail_page_table:
1434         dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1435                      scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
1436  fail:
1437         return -ENOMEM;
1438 }
1439
1440 /* SCSI stack integration */
1441
1442 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1443 {
1444         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1445         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1446         struct sbp2_command_orb *orb;
1447         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1448
1449         /*
1450          * Bidirectional commands are not yet implemented, and unknown
1451          * transfer direction not handled.
1452          */
1453         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1454                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1455                 cmd->result = DID_ERROR << 16;
1456                 done(cmd);
1457                 return 0;
1458         }
1459
1460         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1461         if (orb == NULL) {
1462                 fw_notify("failed to alloc orb\n");
1463                 return SCSI_MLQUEUE_HOST_BUSY;
1464         }
1465
1466         /* Initialize rcode to something not RCODE_COMPLETE. */
1467         orb->base.rcode = -1;
1468         kref_init(&orb->base.kref);
1469
1470         orb->lu   = lu;
1471         orb->done = done;
1472         orb->cmd  = cmd;
1473
1474         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1475         orb->request.misc = cpu_to_be32(
1476                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1477                 COMMAND_ORB_SPEED(device->max_speed) |
1478                 COMMAND_ORB_NOTIFY);
1479
1480         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1481                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1482
1483         generation = device->generation;
1484         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1485
1486         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1487                 goto out;
1488
1489         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1490
1491         orb->base.callback = complete_command_orb;
1492         orb->base.request_bus =
1493                 dma_map_single(device->card->device, &orb->request,
1494                                sizeof(orb->request), DMA_TO_DEVICE);
1495         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1496                 sbp2_unmap_scatterlist(device->card->device, orb);
1497                 goto out;
1498         }
1499
1500         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1501                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1502         retval = 0;
1503  out:
1504         kref_put(&orb->base.kref, free_orb);
1505         return retval;
1506 }
1507
1508 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1509 {
1510         struct sbp2_logical_unit *lu = sdev->hostdata;
1511
1512         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1513         if (!lu)
1514                 return -ENOSYS;
1515
1516         sdev->allow_restart = 1;
1517
1518         /* SBP-2 requires quadlet alignment of the data buffers. */
1519         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1520
1521         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1522                 sdev->inquiry_len = 36;
1523
1524         return 0;
1525 }
1526
1527 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1528 {
1529         struct sbp2_logical_unit *lu = sdev->hostdata;
1530
1531         sdev->use_10_for_rw = 1;
1532
1533         if (sbp2_param_exclusive_login)
1534                 sdev->manage_start_stop = 1;
1535
1536         if (sdev->type == TYPE_ROM)
1537                 sdev->use_10_for_ms = 1;
1538
1539         if (sdev->type == TYPE_DISK &&
1540             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1541                 sdev->skip_ms_page_8 = 1;
1542
1543         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1544                 sdev->fix_capacity = 1;
1545
1546         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1547                 sdev->start_stop_pwr_cond = 1;
1548
1549         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1550                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1551
1552         blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
1553
1554         return 0;
1555 }
1556
1557 /*
1558  * Called by scsi stack when something has really gone wrong.  Usually
1559  * called when a command has timed-out for some reason.
1560  */
1561 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1562 {
1563         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1564
1565         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1566         sbp2_agent_reset(lu);
1567         sbp2_cancel_orbs(lu);
1568
1569         return SUCCESS;
1570 }
1571
1572 /*
1573  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1574  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1575  *
1576  * This is the concatenation of target port identifier and logical unit
1577  * identifier as per SAM-2...SAM-4 annex A.
1578  */
1579 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1580                         struct device_attribute *attr, char *buf)
1581 {
1582         struct scsi_device *sdev = to_scsi_device(dev);
1583         struct sbp2_logical_unit *lu;
1584
1585         if (!sdev)
1586                 return 0;
1587
1588         lu = sdev->hostdata;
1589
1590         return sprintf(buf, "%016llx:%06x:%04x\n",
1591                         (unsigned long long)lu->tgt->guid,
1592                         lu->tgt->directory_id, lu->lun);
1593 }
1594
1595 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1596
1597 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1598         &dev_attr_ieee1394_id,
1599         NULL
1600 };
1601
1602 static struct scsi_host_template scsi_driver_template = {
1603         .module                 = THIS_MODULE,
1604         .name                   = "SBP-2 IEEE-1394",
1605         .proc_name              = sbp2_driver_name,
1606         .queuecommand           = sbp2_scsi_queuecommand,
1607         .slave_alloc            = sbp2_scsi_slave_alloc,
1608         .slave_configure        = sbp2_scsi_slave_configure,
1609         .eh_abort_handler       = sbp2_scsi_abort,
1610         .this_id                = -1,
1611         .sg_tablesize           = SG_ALL,
1612         .use_clustering         = ENABLE_CLUSTERING,
1613         .cmd_per_lun            = 1,
1614         .can_queue              = 1,
1615         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1616 };
1617
1618 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1619 MODULE_DESCRIPTION("SCSI over IEEE1394");
1620 MODULE_LICENSE("GPL");
1621 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1622
1623 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1624 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1625 MODULE_ALIAS("sbp2");
1626 #endif
1627
1628 static int __init sbp2_init(void)
1629 {
1630         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1631         if (!sbp2_wq)
1632                 return -ENOMEM;
1633
1634         return driver_register(&sbp2_driver.driver);
1635 }
1636
1637 static void __exit sbp2_cleanup(void)
1638 {
1639         driver_unregister(&sbp2_driver.driver);
1640         destroy_workqueue(sbp2_wq);
1641 }
1642
1643 module_init(sbp2_init);
1644 module_exit(sbp2_cleanup);