firewire: fix crash in automatic module unloading
[linux-2.6] / 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/delay.h>
33 #include <linux/device.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/kernel.h>
36 #include <linux/mod_devicetable.h>
37 #include <linux/module.h>
38 #include <linux/moduleparam.h>
39 #include <linux/scatterlist.h>
40 #include <linux/string.h>
41 #include <linux/stringify.h>
42 #include <linux/timer.h>
43 #include <linux/workqueue.h>
44 #include <asm/system.h>
45
46 #include <scsi/scsi.h>
47 #include <scsi/scsi_cmnd.h>
48 #include <scsi/scsi_device.h>
49 #include <scsi/scsi_host.h>
50
51 #include "fw-device.h"
52 #include "fw-topology.h"
53 #include "fw-transaction.h"
54
55 /*
56  * So far only bridges from Oxford Semiconductor are known to support
57  * concurrent logins. Depending on firmware, four or two concurrent logins
58  * are possible on OXFW911 and newer Oxsemi bridges.
59  *
60  * Concurrent logins are useful together with cluster filesystems.
61  */
62 static int sbp2_param_exclusive_login = 1;
63 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
64 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
65                  "(default = Y, use N for concurrent initiators)");
66
67 /*
68  * Flags for firmware oddities
69  *
70  * - 128kB max transfer
71  *   Limit transfer size. Necessary for some old bridges.
72  *
73  * - 36 byte inquiry
74  *   When scsi_mod probes the device, let the inquiry command look like that
75  *   from MS Windows.
76  *
77  * - skip mode page 8
78  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
79  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
80  *
81  * - fix capacity
82  *   Tell sd_mod to correct the last sector number reported by read_capacity.
83  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
84  *   Don't use this with devices which don't have this bug.
85  *
86  * - delay inquiry
87  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
88  *
89  * - override internal blacklist
90  *   Instead of adding to the built-in blacklist, use only the workarounds
91  *   specified in the module load parameter.
92  *   Useful if a blacklist entry interfered with a non-broken device.
93  */
94 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
95 #define SBP2_WORKAROUND_INQUIRY_36      0x2
96 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
97 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
98 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
99 #define SBP2_INQUIRY_DELAY              12
100 #define SBP2_WORKAROUND_OVERRIDE        0x100
101
102 static int sbp2_param_workarounds;
103 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
104 MODULE_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         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
111         ", or a combination)");
112
113 /* I don't know why the SCSI stack doesn't define something like this... */
114 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
115
116 static const char sbp2_driver_name[] = "sbp2";
117
118 /*
119  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
120  * and one struct scsi_device per sbp2_logical_unit.
121  */
122 struct sbp2_logical_unit {
123         struct sbp2_target *tgt;
124         struct list_head link;
125         struct fw_address_handler address_handler;
126         struct list_head orb_list;
127
128         u64 command_block_agent_address;
129         u16 lun;
130         int login_id;
131
132         /*
133          * The generation is updated once we've logged in or reconnected
134          * to the logical unit.  Thus, I/O to the device will automatically
135          * fail and get retried if it happens in a window where the device
136          * is not ready, e.g. after a bus reset but before we reconnect.
137          */
138         int generation;
139         int retries;
140         struct delayed_work work;
141         bool has_sdev;
142         bool blocked;
143 };
144
145 /*
146  * We create one struct sbp2_target per IEEE 1212 Unit Directory
147  * and one struct Scsi_Host per sbp2_target.
148  */
149 struct sbp2_target {
150         struct kref kref;
151         struct fw_unit *unit;
152         const char *bus_id;
153         struct list_head lu_list;
154
155         u64 management_agent_address;
156         int directory_id;
157         int node_id;
158         int address_high;
159         unsigned int workarounds;
160         unsigned int mgt_orb_timeout;
161
162         int dont_block; /* counter for each logical unit */
163         int blocked;    /* ditto */
164 };
165
166 /*
167  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
168  * provided in the config rom. Most devices do provide a value, which
169  * we'll use for login management orbs, but with some sane limits.
170  */
171 #define SBP2_MIN_LOGIN_ORB_TIMEOUT      5000U   /* Timeout in ms */
172 #define SBP2_MAX_LOGIN_ORB_TIMEOUT      40000U  /* Timeout in ms */
173 #define SBP2_ORB_TIMEOUT                2000U   /* Timeout in ms */
174 #define SBP2_ORB_NULL                   0x80000000
175 #define SBP2_MAX_SG_ELEMENT_LENGTH      0xf000
176
177 #define SBP2_DIRECTION_TO_MEDIA         0x0
178 #define SBP2_DIRECTION_FROM_MEDIA       0x1
179
180 /* Unit directory keys */
181 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
182 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
183 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
184 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
185
186 /* Management orb opcodes */
187 #define SBP2_LOGIN_REQUEST              0x0
188 #define SBP2_QUERY_LOGINS_REQUEST       0x1
189 #define SBP2_RECONNECT_REQUEST          0x3
190 #define SBP2_SET_PASSWORD_REQUEST       0x4
191 #define SBP2_LOGOUT_REQUEST             0x7
192 #define SBP2_ABORT_TASK_REQUEST         0xb
193 #define SBP2_ABORT_TASK_SET             0xc
194 #define SBP2_LOGICAL_UNIT_RESET         0xe
195 #define SBP2_TARGET_RESET_REQUEST       0xf
196
197 /* Offsets for command block agent registers */
198 #define SBP2_AGENT_STATE                0x00
199 #define SBP2_AGENT_RESET                0x04
200 #define SBP2_ORB_POINTER                0x08
201 #define SBP2_DOORBELL                   0x10
202 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
203
204 /* Status write response codes */
205 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
206 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
207 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
208 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
209
210 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
211 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
212 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
213 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
214 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
215 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
216 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
217 #define STATUS_GET_DATA(v)              ((v).data)
218
219 struct sbp2_status {
220         u32 status;
221         u32 orb_low;
222         u8 data[24];
223 };
224
225 struct sbp2_pointer {
226         u32 high;
227         u32 low;
228 };
229
230 struct sbp2_orb {
231         struct fw_transaction t;
232         struct kref kref;
233         dma_addr_t request_bus;
234         int rcode;
235         struct sbp2_pointer pointer;
236         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
237         struct list_head link;
238 };
239
240 #define MANAGEMENT_ORB_LUN(v)                   ((v))
241 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
242 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
243 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
244 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
245 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
246
247 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
248 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
249
250 struct sbp2_management_orb {
251         struct sbp2_orb base;
252         struct {
253                 struct sbp2_pointer password;
254                 struct sbp2_pointer response;
255                 u32 misc;
256                 u32 length;
257                 struct sbp2_pointer status_fifo;
258         } request;
259         __be32 response[4];
260         dma_addr_t response_bus;
261         struct completion done;
262         struct sbp2_status status;
263 };
264
265 #define LOGIN_RESPONSE_GET_LOGIN_ID(v)  ((v).misc & 0xffff)
266 #define LOGIN_RESPONSE_GET_LENGTH(v)    (((v).misc >> 16) & 0xffff)
267
268 struct sbp2_login_response {
269         u32 misc;
270         struct sbp2_pointer command_block_agent;
271         u32 reconnect_hold;
272 };
273 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
274 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
275 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
276 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
277 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
278 #define COMMAND_ORB_DIRECTION(v)        ((v) << 27)
279 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
280 #define COMMAND_ORB_NOTIFY              ((1) << 31)
281
282 struct sbp2_command_orb {
283         struct sbp2_orb base;
284         struct {
285                 struct sbp2_pointer next;
286                 struct sbp2_pointer data_descriptor;
287                 u32 misc;
288                 u8 command_block[12];
289         } request;
290         struct scsi_cmnd *cmd;
291         scsi_done_fn_t done;
292         struct sbp2_logical_unit *lu;
293
294         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
295         dma_addr_t page_table_bus;
296 };
297
298 /*
299  * List of devices with known bugs.
300  *
301  * The firmware_revision field, masked with 0xffff00, is the best
302  * indicator for the type of bridge chip of a device.  It yields a few
303  * false positives but this did not break correctly behaving devices
304  * so far.  We use ~0 as a wildcard, since the 24 bit values we get
305  * from the config rom can never match that.
306  */
307 static const struct {
308         u32 firmware_revision;
309         u32 model;
310         unsigned int workarounds;
311 } sbp2_workarounds_table[] = {
312         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
313                 .firmware_revision      = 0x002800,
314                 .model                  = 0x001010,
315                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
316                                           SBP2_WORKAROUND_MODE_SENSE_8,
317         },
318         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
319                 .firmware_revision      = 0x002800,
320                 .model                  = 0x000000,
321                 .workarounds            = SBP2_WORKAROUND_DELAY_INQUIRY,
322         },
323         /* Initio bridges, actually only needed for some older ones */ {
324                 .firmware_revision      = 0x000200,
325                 .model                  = ~0,
326                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
327         },
328         /* Symbios bridge */ {
329                 .firmware_revision      = 0xa0b800,
330                 .model                  = ~0,
331                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
332         },
333
334         /*
335          * There are iPods (2nd gen, 3rd gen) with model_id == 0, but
336          * these iPods do not feature the read_capacity bug according
337          * to one report.  Read_capacity behaviour as well as model_id
338          * could change due to Apple-supplied firmware updates though.
339          */
340
341         /* iPod 4th generation. */ {
342                 .firmware_revision      = 0x0a2700,
343                 .model                  = 0x000021,
344                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
345         },
346         /* iPod mini */ {
347                 .firmware_revision      = 0x0a2700,
348                 .model                  = 0x000023,
349                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
350         },
351         /* iPod Photo */ {
352                 .firmware_revision      = 0x0a2700,
353                 .model                  = 0x00007e,
354                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
355         }
356 };
357
358 static void
359 free_orb(struct kref *kref)
360 {
361         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
362
363         kfree(orb);
364 }
365
366 static void
367 sbp2_status_write(struct fw_card *card, struct fw_request *request,
368                   int tcode, int destination, int source,
369                   int generation, int speed,
370                   unsigned long long offset,
371                   void *payload, size_t length, void *callback_data)
372 {
373         struct sbp2_logical_unit *lu = callback_data;
374         struct sbp2_orb *orb;
375         struct sbp2_status status;
376         size_t header_size;
377         unsigned long flags;
378
379         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
380             length == 0 || length > sizeof(status)) {
381                 fw_send_response(card, request, RCODE_TYPE_ERROR);
382                 return;
383         }
384
385         header_size = min(length, 2 * sizeof(u32));
386         fw_memcpy_from_be32(&status, payload, header_size);
387         if (length > header_size)
388                 memcpy(status.data, payload + 8, length - header_size);
389         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
390                 fw_notify("non-orb related status write, not handled\n");
391                 fw_send_response(card, request, RCODE_COMPLETE);
392                 return;
393         }
394
395         /* Lookup the orb corresponding to this status write. */
396         spin_lock_irqsave(&card->lock, flags);
397         list_for_each_entry(orb, &lu->orb_list, link) {
398                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
399                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
400                         orb->rcode = RCODE_COMPLETE;
401                         list_del(&orb->link);
402                         break;
403                 }
404         }
405         spin_unlock_irqrestore(&card->lock, flags);
406
407         if (&orb->link != &lu->orb_list)
408                 orb->callback(orb, &status);
409         else
410                 fw_error("status write for unknown orb\n");
411
412         kref_put(&orb->kref, free_orb);
413
414         fw_send_response(card, request, RCODE_COMPLETE);
415 }
416
417 static void
418 complete_transaction(struct fw_card *card, int rcode,
419                      void *payload, size_t length, void *data)
420 {
421         struct sbp2_orb *orb = data;
422         unsigned long flags;
423
424         /*
425          * This is a little tricky.  We can get the status write for
426          * the orb before we get this callback.  The status write
427          * handler above will assume the orb pointer transaction was
428          * successful and set the rcode to RCODE_COMPLETE for the orb.
429          * So this callback only sets the rcode if it hasn't already
430          * been set and only does the cleanup if the transaction
431          * failed and we didn't already get a status write.
432          */
433         spin_lock_irqsave(&card->lock, flags);
434
435         if (orb->rcode == -1)
436                 orb->rcode = rcode;
437         if (orb->rcode != RCODE_COMPLETE) {
438                 list_del(&orb->link);
439                 spin_unlock_irqrestore(&card->lock, flags);
440                 orb->callback(orb, NULL);
441         } else {
442                 spin_unlock_irqrestore(&card->lock, flags);
443         }
444
445         kref_put(&orb->kref, free_orb);
446 }
447
448 static void
449 sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
450               int node_id, int generation, u64 offset)
451 {
452         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
453         unsigned long flags;
454
455         orb->pointer.high = 0;
456         orb->pointer.low = orb->request_bus;
457         fw_memcpy_to_be32(&orb->pointer, &orb->pointer, sizeof(orb->pointer));
458
459         spin_lock_irqsave(&device->card->lock, flags);
460         list_add_tail(&orb->link, &lu->orb_list);
461         spin_unlock_irqrestore(&device->card->lock, flags);
462
463         /* Take a ref for the orb list and for the transaction callback. */
464         kref_get(&orb->kref);
465         kref_get(&orb->kref);
466
467         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
468                         node_id, generation, device->max_speed, offset,
469                         &orb->pointer, sizeof(orb->pointer),
470                         complete_transaction, orb);
471 }
472
473 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
474 {
475         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
476         struct sbp2_orb *orb, *next;
477         struct list_head list;
478         unsigned long flags;
479         int retval = -ENOENT;
480
481         INIT_LIST_HEAD(&list);
482         spin_lock_irqsave(&device->card->lock, flags);
483         list_splice_init(&lu->orb_list, &list);
484         spin_unlock_irqrestore(&device->card->lock, flags);
485
486         list_for_each_entry_safe(orb, next, &list, link) {
487                 retval = 0;
488                 if (fw_cancel_transaction(device->card, &orb->t) == 0)
489                         continue;
490
491                 orb->rcode = RCODE_CANCELLED;
492                 orb->callback(orb, NULL);
493         }
494
495         return retval;
496 }
497
498 static void
499 complete_management_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
500 {
501         struct sbp2_management_orb *orb =
502                 container_of(base_orb, struct sbp2_management_orb, base);
503
504         if (status)
505                 memcpy(&orb->status, status, sizeof(*status));
506         complete(&orb->done);
507 }
508
509 static int
510 sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
511                          int generation, int function, int lun_or_login_id,
512                          void *response)
513 {
514         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
515         struct sbp2_management_orb *orb;
516         unsigned int timeout;
517         int retval = -ENOMEM;
518
519         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
520                 return 0;
521
522         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
523         if (orb == NULL)
524                 return -ENOMEM;
525
526         kref_init(&orb->base.kref);
527         orb->response_bus =
528                 dma_map_single(device->card->device, &orb->response,
529                                sizeof(orb->response), DMA_FROM_DEVICE);
530         if (dma_mapping_error(orb->response_bus))
531                 goto fail_mapping_response;
532
533         orb->request.response.high    = 0;
534         orb->request.response.low     = orb->response_bus;
535
536         orb->request.misc =
537                 MANAGEMENT_ORB_NOTIFY |
538                 MANAGEMENT_ORB_FUNCTION(function) |
539                 MANAGEMENT_ORB_LUN(lun_or_login_id);
540         orb->request.length =
541                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response));
542
543         orb->request.status_fifo.high = lu->address_handler.offset >> 32;
544         orb->request.status_fifo.low  = lu->address_handler.offset;
545
546         if (function == SBP2_LOGIN_REQUEST) {
547                 /* Ask for 2^2 == 4 seconds reconnect grace period */
548                 orb->request.misc |=
549                         MANAGEMENT_ORB_RECONNECT(2) |
550                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login);
551                 timeout = lu->tgt->mgt_orb_timeout;
552         } else {
553                 timeout = SBP2_ORB_TIMEOUT;
554         }
555
556         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
557
558         init_completion(&orb->done);
559         orb->base.callback = complete_management_orb;
560
561         orb->base.request_bus =
562                 dma_map_single(device->card->device, &orb->request,
563                                sizeof(orb->request), DMA_TO_DEVICE);
564         if (dma_mapping_error(orb->base.request_bus))
565                 goto fail_mapping_request;
566
567         sbp2_send_orb(&orb->base, lu, node_id, generation,
568                       lu->tgt->management_agent_address);
569
570         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
571
572         retval = -EIO;
573         if (sbp2_cancel_orbs(lu) == 0) {
574                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
575                          lu->tgt->bus_id, orb->base.rcode);
576                 goto out;
577         }
578
579         if (orb->base.rcode != RCODE_COMPLETE) {
580                 fw_error("%s: management write failed, rcode 0x%02x\n",
581                          lu->tgt->bus_id, orb->base.rcode);
582                 goto out;
583         }
584
585         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
586             STATUS_GET_SBP_STATUS(orb->status) != 0) {
587                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
588                          STATUS_GET_RESPONSE(orb->status),
589                          STATUS_GET_SBP_STATUS(orb->status));
590                 goto out;
591         }
592
593         retval = 0;
594  out:
595         dma_unmap_single(device->card->device, orb->base.request_bus,
596                          sizeof(orb->request), DMA_TO_DEVICE);
597  fail_mapping_request:
598         dma_unmap_single(device->card->device, orb->response_bus,
599                          sizeof(orb->response), DMA_FROM_DEVICE);
600  fail_mapping_response:
601         if (response)
602                 fw_memcpy_from_be32(response,
603                                     orb->response, sizeof(orb->response));
604         kref_put(&orb->base.kref, free_orb);
605
606         return retval;
607 }
608
609 static void
610 complete_agent_reset_write(struct fw_card *card, int rcode,
611                            void *payload, size_t length, void *done)
612 {
613         complete(done);
614 }
615
616 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
617 {
618         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
619         DECLARE_COMPLETION_ONSTACK(done);
620         struct fw_transaction t;
621         static u32 z;
622
623         fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
624                         lu->tgt->node_id, lu->generation, device->max_speed,
625                         lu->command_block_agent_address + SBP2_AGENT_RESET,
626                         &z, sizeof(z), complete_agent_reset_write, &done);
627         wait_for_completion(&done);
628 }
629
630 static void
631 complete_agent_reset_write_no_wait(struct fw_card *card, int rcode,
632                                    void *payload, size_t length, void *data)
633 {
634         kfree(data);
635 }
636
637 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
638 {
639         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
640         struct fw_transaction *t;
641         static u32 z;
642
643         t = kmalloc(sizeof(*t), GFP_ATOMIC);
644         if (t == NULL)
645                 return;
646
647         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
648                         lu->tgt->node_id, lu->generation, device->max_speed,
649                         lu->command_block_agent_address + SBP2_AGENT_RESET,
650                         &z, sizeof(z), complete_agent_reset_write_no_wait, t);
651 }
652
653 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
654 {
655         struct fw_card *card = fw_device(lu->tgt->unit->device.parent)->card;
656         unsigned long flags;
657
658         /* serialize with comparisons of lu->generation and card->generation */
659         spin_lock_irqsave(&card->lock, flags);
660         lu->generation = generation;
661         spin_unlock_irqrestore(&card->lock, flags);
662 }
663
664 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
665 {
666         /*
667          * We may access dont_block without taking card->lock here:
668          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
669          * are currently serialized against each other.
670          * And a wrong result in sbp2_conditionally_block()'s access of
671          * dont_block is rather harmless, it simply misses its first chance.
672          */
673         --lu->tgt->dont_block;
674 }
675
676 /*
677  * Blocks lu->tgt if all of the following conditions are met:
678  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
679  *     logical units have been finished (indicated by dont_block == 0).
680  *   - lu->generation is stale.
681  *
682  * Note, scsi_block_requests() must be called while holding card->lock,
683  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
684  * unblock the target.
685  */
686 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
687 {
688         struct sbp2_target *tgt = lu->tgt;
689         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
690         struct Scsi_Host *shost =
691                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
692         unsigned long flags;
693
694         spin_lock_irqsave(&card->lock, flags);
695         if (!tgt->dont_block && !lu->blocked &&
696             lu->generation != card->generation) {
697                 lu->blocked = true;
698                 if (++tgt->blocked == 1) {
699                         scsi_block_requests(shost);
700                         fw_notify("blocked %s\n", lu->tgt->bus_id);
701                 }
702         }
703         spin_unlock_irqrestore(&card->lock, flags);
704 }
705
706 /*
707  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
708  * Note, it is harmless to run scsi_unblock_requests() outside the
709  * card->lock protected section.  On the other hand, running it inside
710  * the section might clash with shost->host_lock.
711  */
712 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
713 {
714         struct sbp2_target *tgt = lu->tgt;
715         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
716         struct Scsi_Host *shost =
717                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
718         unsigned long flags;
719         bool unblock = false;
720
721         spin_lock_irqsave(&card->lock, flags);
722         if (lu->blocked && lu->generation == card->generation) {
723                 lu->blocked = false;
724                 unblock = --tgt->blocked == 0;
725         }
726         spin_unlock_irqrestore(&card->lock, flags);
727
728         if (unblock) {
729                 scsi_unblock_requests(shost);
730                 fw_notify("unblocked %s\n", lu->tgt->bus_id);
731         }
732 }
733
734 /*
735  * Prevents future blocking of tgt and unblocks it.
736  * Note, it is harmless to run scsi_unblock_requests() outside the
737  * card->lock protected section.  On the other hand, running it inside
738  * the section might clash with shost->host_lock.
739  */
740 static void sbp2_unblock(struct sbp2_target *tgt)
741 {
742         struct fw_card *card = fw_device(tgt->unit->device.parent)->card;
743         struct Scsi_Host *shost =
744                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
745         unsigned long flags;
746
747         spin_lock_irqsave(&card->lock, flags);
748         ++tgt->dont_block;
749         spin_unlock_irqrestore(&card->lock, flags);
750
751         scsi_unblock_requests(shost);
752 }
753
754 static int sbp2_lun2int(u16 lun)
755 {
756         struct scsi_lun eight_bytes_lun;
757
758         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
759         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
760         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
761
762         return scsilun_to_int(&eight_bytes_lun);
763 }
764
765 static void sbp2_release_target(struct kref *kref)
766 {
767         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
768         struct sbp2_logical_unit *lu, *next;
769         struct Scsi_Host *shost =
770                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
771         struct scsi_device *sdev;
772         struct fw_device *device = fw_device(tgt->unit->device.parent);
773
774         /* prevent deadlocks */
775         sbp2_unblock(tgt);
776
777         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
778                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
779                 if (sdev) {
780                         scsi_remove_device(sdev);
781                         scsi_device_put(sdev);
782                 }
783                 sbp2_send_management_orb(lu, tgt->node_id, lu->generation,
784                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
785
786                 fw_core_remove_address_handler(&lu->address_handler);
787                 list_del(&lu->link);
788                 kfree(lu);
789         }
790         scsi_remove_host(shost);
791         fw_notify("released %s\n", tgt->bus_id);
792
793         put_device(&tgt->unit->device);
794         scsi_host_put(shost);
795         fw_device_put(device);
796 }
797
798 static struct workqueue_struct *sbp2_wq;
799
800 /*
801  * Always get the target's kref when scheduling work on one its units.
802  * Each workqueue job is responsible to call sbp2_target_put() upon return.
803  */
804 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
805 {
806         if (queue_delayed_work(sbp2_wq, &lu->work, delay))
807                 kref_get(&lu->tgt->kref);
808 }
809
810 static void sbp2_target_put(struct sbp2_target *tgt)
811 {
812         kref_put(&tgt->kref, sbp2_release_target);
813 }
814
815 static void sbp2_reconnect(struct work_struct *work);
816
817 static void sbp2_login(struct work_struct *work)
818 {
819         struct sbp2_logical_unit *lu =
820                 container_of(work, struct sbp2_logical_unit, work.work);
821         struct sbp2_target *tgt = lu->tgt;
822         struct fw_device *device = fw_device(tgt->unit->device.parent);
823         struct Scsi_Host *shost;
824         struct scsi_device *sdev;
825         struct sbp2_login_response response;
826         int generation, node_id, local_node_id;
827
828         if (fw_device_is_shutdown(device))
829                 goto out;
830
831         generation    = device->generation;
832         smp_rmb();    /* node_id must not be older than generation */
833         node_id       = device->node_id;
834         local_node_id = device->card->node_id;
835
836         /* If this is a re-login attempt, log out, or we might be rejected. */
837         if (lu->has_sdev)
838                 sbp2_send_management_orb(lu, device->node_id, generation,
839                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
840
841         if (sbp2_send_management_orb(lu, node_id, generation,
842                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
843                 if (lu->retries++ < 5) {
844                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
845                 } else {
846                         fw_error("%s: failed to login to LUN %04x\n",
847                                  tgt->bus_id, lu->lun);
848                         /* Let any waiting I/O fail from now on. */
849                         sbp2_unblock(lu->tgt);
850                 }
851                 goto out;
852         }
853
854         tgt->node_id      = node_id;
855         tgt->address_high = local_node_id << 16;
856         sbp2_set_generation(lu, generation);
857
858         /* Get command block agent offset and login id. */
859         lu->command_block_agent_address =
860                 ((u64) (response.command_block_agent.high & 0xffff) << 32) |
861                 response.command_block_agent.low;
862         lu->login_id = LOGIN_RESPONSE_GET_LOGIN_ID(response);
863
864         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
865                   tgt->bus_id, lu->lun, lu->retries);
866
867 #if 0
868         /* FIXME: The linux1394 sbp2 does this last step. */
869         sbp2_set_busy_timeout(scsi_id);
870 #endif
871
872         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
873         sbp2_agent_reset(lu);
874
875         /* This was a re-login. */
876         if (lu->has_sdev) {
877                 sbp2_cancel_orbs(lu);
878                 sbp2_conditionally_unblock(lu);
879                 goto out;
880         }
881
882         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
883                 ssleep(SBP2_INQUIRY_DELAY);
884
885         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
886         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
887         /*
888          * FIXME:  We are unable to perform reconnects while in sbp2_login().
889          * Therefore __scsi_add_device() will get into trouble if a bus reset
890          * happens in parallel.  It will either fail or leave us with an
891          * unusable sdev.  As a workaround we check for this and retry the
892          * whole login and SCSI probing.
893          */
894
895         /* Reported error during __scsi_add_device() */
896         if (IS_ERR(sdev))
897                 goto out_logout_login;
898
899         /* Unreported error during __scsi_add_device() */
900         smp_rmb(); /* get current card generation */
901         if (generation != device->card->generation) {
902                 scsi_remove_device(sdev);
903                 scsi_device_put(sdev);
904                 goto out_logout_login;
905         }
906
907         /* No error during __scsi_add_device() */
908         lu->has_sdev = true;
909         scsi_device_put(sdev);
910         sbp2_allow_block(lu);
911         goto out;
912
913  out_logout_login:
914         smp_rmb(); /* generation may have changed */
915         generation = device->generation;
916         smp_rmb(); /* node_id must not be older than generation */
917
918         sbp2_send_management_orb(lu, device->node_id, generation,
919                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
920         /*
921          * If a bus reset happened, sbp2_update will have requeued
922          * lu->work already.  Reset the work from reconnect to login.
923          */
924         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
925  out:
926         sbp2_target_put(tgt);
927 }
928
929 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
930 {
931         struct sbp2_logical_unit *lu;
932
933         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
934         if (!lu)
935                 return -ENOMEM;
936
937         lu->address_handler.length           = 0x100;
938         lu->address_handler.address_callback = sbp2_status_write;
939         lu->address_handler.callback_data    = lu;
940
941         if (fw_core_add_address_handler(&lu->address_handler,
942                                         &fw_high_memory_region) < 0) {
943                 kfree(lu);
944                 return -ENOMEM;
945         }
946
947         lu->tgt      = tgt;
948         lu->lun      = lun_entry & 0xffff;
949         lu->retries  = 0;
950         lu->has_sdev = false;
951         lu->blocked  = false;
952         ++tgt->dont_block;
953         INIT_LIST_HEAD(&lu->orb_list);
954         INIT_DELAYED_WORK(&lu->work, sbp2_login);
955
956         list_add_tail(&lu->link, &tgt->lu_list);
957         return 0;
958 }
959
960 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt, u32 *directory)
961 {
962         struct fw_csr_iterator ci;
963         int key, value;
964
965         fw_csr_iterator_init(&ci, directory);
966         while (fw_csr_iterator_next(&ci, &key, &value))
967                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
968                     sbp2_add_logical_unit(tgt, value) < 0)
969                         return -ENOMEM;
970         return 0;
971 }
972
973 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
974                               u32 *model, u32 *firmware_revision)
975 {
976         struct fw_csr_iterator ci;
977         int key, value;
978         unsigned int timeout;
979
980         fw_csr_iterator_init(&ci, directory);
981         while (fw_csr_iterator_next(&ci, &key, &value)) {
982                 switch (key) {
983
984                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
985                         tgt->management_agent_address =
986                                         CSR_REGISTER_BASE + 4 * value;
987                         break;
988
989                 case CSR_DIRECTORY_ID:
990                         tgt->directory_id = value;
991                         break;
992
993                 case CSR_MODEL:
994                         *model = value;
995                         break;
996
997                 case SBP2_CSR_FIRMWARE_REVISION:
998                         *firmware_revision = value;
999                         break;
1000
1001                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1002                         /* the timeout value is stored in 500ms units */
1003                         timeout = ((unsigned int) value >> 8 & 0xff) * 500;
1004                         timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT);
1005                         tgt->mgt_orb_timeout =
1006                                   min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT);
1007
1008                         if (timeout > tgt->mgt_orb_timeout)
1009                                 fw_notify("%s: config rom contains %ds "
1010                                           "management ORB timeout, limiting "
1011                                           "to %ds\n", tgt->bus_id,
1012                                           timeout / 1000,
1013                                           tgt->mgt_orb_timeout / 1000);
1014                         break;
1015
1016                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1017                         if (sbp2_add_logical_unit(tgt, value) < 0)
1018                                 return -ENOMEM;
1019                         break;
1020
1021                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1022                         if (sbp2_scan_logical_unit_dir(tgt, ci.p + value) < 0)
1023                                 return -ENOMEM;
1024                         break;
1025                 }
1026         }
1027         return 0;
1028 }
1029
1030 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1031                                   u32 firmware_revision)
1032 {
1033         int i;
1034         unsigned int w = sbp2_param_workarounds;
1035
1036         if (w)
1037                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1038                           "if you need the workarounds parameter for %s\n",
1039                           tgt->bus_id);
1040
1041         if (w & SBP2_WORKAROUND_OVERRIDE)
1042                 goto out;
1043
1044         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1045
1046                 if (sbp2_workarounds_table[i].firmware_revision !=
1047                     (firmware_revision & 0xffffff00))
1048                         continue;
1049
1050                 if (sbp2_workarounds_table[i].model != model &&
1051                     sbp2_workarounds_table[i].model != ~0)
1052                         continue;
1053
1054                 w |= sbp2_workarounds_table[i].workarounds;
1055                 break;
1056         }
1057  out:
1058         if (w)
1059                 fw_notify("Workarounds for %s: 0x%x "
1060                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1061                           tgt->bus_id, w, firmware_revision, model);
1062         tgt->workarounds = w;
1063 }
1064
1065 static struct scsi_host_template scsi_driver_template;
1066
1067 static int sbp2_probe(struct device *dev)
1068 {
1069         struct fw_unit *unit = fw_unit(dev);
1070         struct fw_device *device = fw_device(unit->device.parent);
1071         struct sbp2_target *tgt;
1072         struct sbp2_logical_unit *lu;
1073         struct Scsi_Host *shost;
1074         u32 model, firmware_revision;
1075
1076         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1077         if (shost == NULL)
1078                 return -ENOMEM;
1079
1080         tgt = (struct sbp2_target *)shost->hostdata;
1081         unit->device.driver_data = tgt;
1082         tgt->unit = unit;
1083         kref_init(&tgt->kref);
1084         INIT_LIST_HEAD(&tgt->lu_list);
1085         tgt->bus_id = unit->device.bus_id;
1086
1087         if (fw_device_enable_phys_dma(device) < 0)
1088                 goto fail_shost_put;
1089
1090         if (scsi_add_host(shost, &unit->device) < 0)
1091                 goto fail_shost_put;
1092
1093         fw_device_get(device);
1094
1095         /* Initialize to values that won't match anything in our table. */
1096         firmware_revision = 0xff000000;
1097         model = 0xff000000;
1098
1099         /* implicit directory ID */
1100         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1101                              + CSR_CONFIG_ROM) & 0xffffff;
1102
1103         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1104                                &firmware_revision) < 0)
1105                 goto fail_tgt_put;
1106
1107         sbp2_init_workarounds(tgt, model, firmware_revision);
1108
1109         get_device(&unit->device);
1110
1111         /* Do the login in a workqueue so we can easily reschedule retries. */
1112         list_for_each_entry(lu, &tgt->lu_list, link)
1113                 sbp2_queue_work(lu, 0);
1114         return 0;
1115
1116  fail_tgt_put:
1117         sbp2_target_put(tgt);
1118         return -ENOMEM;
1119
1120  fail_shost_put:
1121         scsi_host_put(shost);
1122         return -ENOMEM;
1123 }
1124
1125 static int sbp2_remove(struct device *dev)
1126 {
1127         struct fw_unit *unit = fw_unit(dev);
1128         struct sbp2_target *tgt = unit->device.driver_data;
1129
1130         sbp2_target_put(tgt);
1131         return 0;
1132 }
1133
1134 static void sbp2_reconnect(struct work_struct *work)
1135 {
1136         struct sbp2_logical_unit *lu =
1137                 container_of(work, struct sbp2_logical_unit, work.work);
1138         struct sbp2_target *tgt = lu->tgt;
1139         struct fw_device *device = fw_device(tgt->unit->device.parent);
1140         int generation, node_id, local_node_id;
1141
1142         if (fw_device_is_shutdown(device))
1143                 goto out;
1144
1145         generation    = device->generation;
1146         smp_rmb();    /* node_id must not be older than generation */
1147         node_id       = device->node_id;
1148         local_node_id = device->card->node_id;
1149
1150         if (sbp2_send_management_orb(lu, node_id, generation,
1151                                      SBP2_RECONNECT_REQUEST,
1152                                      lu->login_id, NULL) < 0) {
1153                 /*
1154                  * If reconnect was impossible even though we are in the
1155                  * current generation, fall back and try to log in again.
1156                  *
1157                  * We could check for "Function rejected" status, but
1158                  * looking at the bus generation as simpler and more general.
1159                  */
1160                 smp_rmb(); /* get current card generation */
1161                 if (generation == device->card->generation ||
1162                     lu->retries++ >= 5) {
1163                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1164                         lu->retries = 0;
1165                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1166                 }
1167                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1168                 goto out;
1169         }
1170
1171         tgt->node_id      = node_id;
1172         tgt->address_high = local_node_id << 16;
1173         sbp2_set_generation(lu, generation);
1174
1175         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1176                   tgt->bus_id, lu->lun, lu->retries);
1177
1178         sbp2_agent_reset(lu);
1179         sbp2_cancel_orbs(lu);
1180         sbp2_conditionally_unblock(lu);
1181  out:
1182         sbp2_target_put(tgt);
1183 }
1184
1185 static void sbp2_update(struct fw_unit *unit)
1186 {
1187         struct sbp2_target *tgt = unit->device.driver_data;
1188         struct sbp2_logical_unit *lu;
1189
1190         fw_device_enable_phys_dma(fw_device(unit->device.parent));
1191
1192         /*
1193          * Fw-core serializes sbp2_update() against sbp2_remove().
1194          * Iteration over tgt->lu_list is therefore safe here.
1195          */
1196         list_for_each_entry(lu, &tgt->lu_list, link) {
1197                 sbp2_conditionally_block(lu);
1198                 lu->retries = 0;
1199                 sbp2_queue_work(lu, 0);
1200         }
1201 }
1202
1203 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1204 #define SBP2_SW_VERSION_ENTRY   0x00010483
1205
1206 static const struct fw_device_id sbp2_id_table[] = {
1207         {
1208                 .match_flags  = FW_MATCH_SPECIFIER_ID | FW_MATCH_VERSION,
1209                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1210                 .version      = SBP2_SW_VERSION_ENTRY,
1211         },
1212         { }
1213 };
1214
1215 static struct fw_driver sbp2_driver = {
1216         .driver   = {
1217                 .owner  = THIS_MODULE,
1218                 .name   = sbp2_driver_name,
1219                 .bus    = &fw_bus_type,
1220                 .probe  = sbp2_probe,
1221                 .remove = sbp2_remove,
1222         },
1223         .update   = sbp2_update,
1224         .id_table = sbp2_id_table,
1225 };
1226
1227 static unsigned int
1228 sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1229 {
1230         int sam_status;
1231
1232         sense_data[0] = 0x70;
1233         sense_data[1] = 0x0;
1234         sense_data[2] = sbp2_status[1];
1235         sense_data[3] = sbp2_status[4];
1236         sense_data[4] = sbp2_status[5];
1237         sense_data[5] = sbp2_status[6];
1238         sense_data[6] = sbp2_status[7];
1239         sense_data[7] = 10;
1240         sense_data[8] = sbp2_status[8];
1241         sense_data[9] = sbp2_status[9];
1242         sense_data[10] = sbp2_status[10];
1243         sense_data[11] = sbp2_status[11];
1244         sense_data[12] = sbp2_status[2];
1245         sense_data[13] = sbp2_status[3];
1246         sense_data[14] = sbp2_status[12];
1247         sense_data[15] = sbp2_status[13];
1248
1249         sam_status = sbp2_status[0] & 0x3f;
1250
1251         switch (sam_status) {
1252         case SAM_STAT_GOOD:
1253         case SAM_STAT_CHECK_CONDITION:
1254         case SAM_STAT_CONDITION_MET:
1255         case SAM_STAT_BUSY:
1256         case SAM_STAT_RESERVATION_CONFLICT:
1257         case SAM_STAT_COMMAND_TERMINATED:
1258                 return DID_OK << 16 | sam_status;
1259
1260         default:
1261                 return DID_ERROR << 16;
1262         }
1263 }
1264
1265 static void
1266 complete_command_orb(struct sbp2_orb *base_orb, struct sbp2_status *status)
1267 {
1268         struct sbp2_command_orb *orb =
1269                 container_of(base_orb, struct sbp2_command_orb, base);
1270         struct fw_device *device = fw_device(orb->lu->tgt->unit->device.parent);
1271         int result;
1272
1273         if (status != NULL) {
1274                 if (STATUS_GET_DEAD(*status))
1275                         sbp2_agent_reset_no_wait(orb->lu);
1276
1277                 switch (STATUS_GET_RESPONSE(*status)) {
1278                 case SBP2_STATUS_REQUEST_COMPLETE:
1279                         result = DID_OK << 16;
1280                         break;
1281                 case SBP2_STATUS_TRANSPORT_FAILURE:
1282                         result = DID_BUS_BUSY << 16;
1283                         break;
1284                 case SBP2_STATUS_ILLEGAL_REQUEST:
1285                 case SBP2_STATUS_VENDOR_DEPENDENT:
1286                 default:
1287                         result = DID_ERROR << 16;
1288                         break;
1289                 }
1290
1291                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1292                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1293                                                            orb->cmd->sense_buffer);
1294         } else {
1295                 /*
1296                  * If the orb completes with status == NULL, something
1297                  * went wrong, typically a bus reset happened mid-orb
1298                  * or when sending the write (less likely).
1299                  */
1300                 result = DID_BUS_BUSY << 16;
1301                 sbp2_conditionally_block(orb->lu);
1302         }
1303
1304         dma_unmap_single(device->card->device, orb->base.request_bus,
1305                          sizeof(orb->request), DMA_TO_DEVICE);
1306
1307         if (scsi_sg_count(orb->cmd) > 0)
1308                 dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1309                              scsi_sg_count(orb->cmd),
1310                              orb->cmd->sc_data_direction);
1311
1312         if (orb->page_table_bus != 0)
1313                 dma_unmap_single(device->card->device, orb->page_table_bus,
1314                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1315
1316         orb->cmd->result = result;
1317         orb->done(orb->cmd);
1318 }
1319
1320 static int
1321 sbp2_map_scatterlist(struct sbp2_command_orb *orb, struct fw_device *device,
1322                      struct sbp2_logical_unit *lu)
1323 {
1324         struct scatterlist *sg;
1325         int sg_len, l, i, j, count;
1326         dma_addr_t sg_addr;
1327
1328         sg = scsi_sglist(orb->cmd);
1329         count = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1330                            orb->cmd->sc_data_direction);
1331         if (count == 0)
1332                 goto fail;
1333
1334         /*
1335          * Handle the special case where there is only one element in
1336          * the scatter list by converting it to an immediate block
1337          * request. This is also a workaround for broken devices such
1338          * as the second generation iPod which doesn't support page
1339          * tables.
1340          */
1341         if (count == 1 && sg_dma_len(sg) < SBP2_MAX_SG_ELEMENT_LENGTH) {
1342                 orb->request.data_descriptor.high = lu->tgt->address_high;
1343                 orb->request.data_descriptor.low  = sg_dma_address(sg);
1344                 orb->request.misc |= COMMAND_ORB_DATA_SIZE(sg_dma_len(sg));
1345                 return 0;
1346         }
1347
1348         /*
1349          * Convert the scatterlist to an sbp2 page table.  If any
1350          * scatterlist entries are too big for sbp2, we split them as we
1351          * go.  Even if we ask the block I/O layer to not give us sg
1352          * elements larger than 65535 bytes, some IOMMUs may merge sg elements
1353          * during DMA mapping, and Linux currently doesn't prevent this.
1354          */
1355         for (i = 0, j = 0; i < count; i++, sg = sg_next(sg)) {
1356                 sg_len = sg_dma_len(sg);
1357                 sg_addr = sg_dma_address(sg);
1358                 while (sg_len) {
1359                         /* FIXME: This won't get us out of the pinch. */
1360                         if (unlikely(j >= ARRAY_SIZE(orb->page_table))) {
1361                                 fw_error("page table overflow\n");
1362                                 goto fail_page_table;
1363                         }
1364                         l = min(sg_len, SBP2_MAX_SG_ELEMENT_LENGTH);
1365                         orb->page_table[j].low = sg_addr;
1366                         orb->page_table[j].high = (l << 16);
1367                         sg_addr += l;
1368                         sg_len -= l;
1369                         j++;
1370                 }
1371         }
1372
1373         fw_memcpy_to_be32(orb->page_table, orb->page_table,
1374                           sizeof(orb->page_table[0]) * j);
1375         orb->page_table_bus =
1376                 dma_map_single(device->card->device, orb->page_table,
1377                                sizeof(orb->page_table), DMA_TO_DEVICE);
1378         if (dma_mapping_error(orb->page_table_bus))
1379                 goto fail_page_table;
1380
1381         /*
1382          * The data_descriptor pointer is the one case where we need
1383          * to fill in the node ID part of the address.  All other
1384          * pointers assume that the data referenced reside on the
1385          * initiator (i.e. us), but data_descriptor can refer to data
1386          * on other nodes so we need to put our ID in descriptor.high.
1387          */
1388         orb->request.data_descriptor.high = lu->tgt->address_high;
1389         orb->request.data_descriptor.low  = orb->page_table_bus;
1390         orb->request.misc |=
1391                 COMMAND_ORB_PAGE_TABLE_PRESENT |
1392                 COMMAND_ORB_DATA_SIZE(j);
1393
1394         return 0;
1395
1396  fail_page_table:
1397         dma_unmap_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1398                      orb->cmd->sc_data_direction);
1399  fail:
1400         return -ENOMEM;
1401 }
1402
1403 /* SCSI stack integration */
1404
1405 static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1406 {
1407         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1408         struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
1409         struct sbp2_command_orb *orb;
1410         unsigned int max_payload;
1411         int retval = SCSI_MLQUEUE_HOST_BUSY;
1412
1413         /*
1414          * Bidirectional commands are not yet implemented, and unknown
1415          * transfer direction not handled.
1416          */
1417         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1418                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1419                 cmd->result = DID_ERROR << 16;
1420                 done(cmd);
1421                 return 0;
1422         }
1423
1424         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1425         if (orb == NULL) {
1426                 fw_notify("failed to alloc orb\n");
1427                 return SCSI_MLQUEUE_HOST_BUSY;
1428         }
1429
1430         /* Initialize rcode to something not RCODE_COMPLETE. */
1431         orb->base.rcode = -1;
1432         kref_init(&orb->base.kref);
1433
1434         orb->lu   = lu;
1435         orb->done = done;
1436         orb->cmd  = cmd;
1437
1438         orb->request.next.high   = SBP2_ORB_NULL;
1439         orb->request.next.low    = 0x0;
1440         /*
1441          * At speed 100 we can do 512 bytes per packet, at speed 200,
1442          * 1024 bytes per packet etc.  The SBP-2 max_payload field
1443          * specifies the max payload size as 2 ^ (max_payload + 2), so
1444          * if we set this to max_speed + 7, we get the right value.
1445          */
1446         max_payload = min(device->max_speed + 7,
1447                           device->card->max_receive - 1);
1448         orb->request.misc =
1449                 COMMAND_ORB_MAX_PAYLOAD(max_payload) |
1450                 COMMAND_ORB_SPEED(device->max_speed) |
1451                 COMMAND_ORB_NOTIFY;
1452
1453         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1454                 orb->request.misc |=
1455                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_FROM_MEDIA);
1456         else if (cmd->sc_data_direction == DMA_TO_DEVICE)
1457                 orb->request.misc |=
1458                         COMMAND_ORB_DIRECTION(SBP2_DIRECTION_TO_MEDIA);
1459
1460         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1461                 goto out;
1462
1463         fw_memcpy_to_be32(&orb->request, &orb->request, sizeof(orb->request));
1464
1465         memset(orb->request.command_block,
1466                0, sizeof(orb->request.command_block));
1467         memcpy(orb->request.command_block, cmd->cmnd, COMMAND_SIZE(*cmd->cmnd));
1468
1469         orb->base.callback = complete_command_orb;
1470         orb->base.request_bus =
1471                 dma_map_single(device->card->device, &orb->request,
1472                                sizeof(orb->request), DMA_TO_DEVICE);
1473         if (dma_mapping_error(orb->base.request_bus))
1474                 goto out;
1475
1476         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, lu->generation,
1477                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1478         retval = 0;
1479  out:
1480         kref_put(&orb->base.kref, free_orb);
1481         return retval;
1482 }
1483
1484 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1485 {
1486         struct sbp2_logical_unit *lu = sdev->hostdata;
1487
1488         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1489         if (!lu)
1490                 return -ENOSYS;
1491
1492         sdev->allow_restart = 1;
1493
1494         /*
1495          * Update the dma alignment (minimum alignment requirements for
1496          * start and end of DMA transfers) to be a sector
1497          */
1498         blk_queue_update_dma_alignment(sdev->request_queue, 511);
1499
1500         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1501                 sdev->inquiry_len = 36;
1502
1503         return 0;
1504 }
1505
1506 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1507 {
1508         struct sbp2_logical_unit *lu = sdev->hostdata;
1509
1510         sdev->use_10_for_rw = 1;
1511
1512         if (sdev->type == TYPE_ROM)
1513                 sdev->use_10_for_ms = 1;
1514
1515         if (sdev->type == TYPE_DISK &&
1516             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1517                 sdev->skip_ms_page_8 = 1;
1518
1519         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1520                 sdev->fix_capacity = 1;
1521
1522         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1523                 blk_queue_max_sectors(sdev->request_queue, 128 * 1024 / 512);
1524
1525         return 0;
1526 }
1527
1528 /*
1529  * Called by scsi stack when something has really gone wrong.  Usually
1530  * called when a command has timed-out for some reason.
1531  */
1532 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1533 {
1534         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1535
1536         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1537         sbp2_agent_reset(lu);
1538         sbp2_cancel_orbs(lu);
1539
1540         return SUCCESS;
1541 }
1542
1543 /*
1544  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1545  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1546  *
1547  * This is the concatenation of target port identifier and logical unit
1548  * identifier as per SAM-2...SAM-4 annex A.
1549  */
1550 static ssize_t
1551 sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
1552                             char *buf)
1553 {
1554         struct scsi_device *sdev = to_scsi_device(dev);
1555         struct sbp2_logical_unit *lu;
1556         struct fw_device *device;
1557
1558         if (!sdev)
1559                 return 0;
1560
1561         lu = sdev->hostdata;
1562         device = fw_device(lu->tgt->unit->device.parent);
1563
1564         return sprintf(buf, "%08x%08x:%06x:%04x\n",
1565                         device->config_rom[3], device->config_rom[4],
1566                         lu->tgt->directory_id, lu->lun);
1567 }
1568
1569 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1570
1571 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1572         &dev_attr_ieee1394_id,
1573         NULL
1574 };
1575
1576 static struct scsi_host_template scsi_driver_template = {
1577         .module                 = THIS_MODULE,
1578         .name                   = "SBP-2 IEEE-1394",
1579         .proc_name              = sbp2_driver_name,
1580         .queuecommand           = sbp2_scsi_queuecommand,
1581         .slave_alloc            = sbp2_scsi_slave_alloc,
1582         .slave_configure        = sbp2_scsi_slave_configure,
1583         .eh_abort_handler       = sbp2_scsi_abort,
1584         .this_id                = -1,
1585         .sg_tablesize           = SG_ALL,
1586         .use_clustering         = ENABLE_CLUSTERING,
1587         .cmd_per_lun            = 1,
1588         .can_queue              = 1,
1589         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1590 };
1591
1592 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1593 MODULE_DESCRIPTION("SCSI over IEEE1394");
1594 MODULE_LICENSE("GPL");
1595 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1596
1597 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1598 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1599 MODULE_ALIAS("sbp2");
1600 #endif
1601
1602 static int __init sbp2_init(void)
1603 {
1604         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1605         if (!sbp2_wq)
1606                 return -ENOMEM;
1607
1608         return driver_register(&sbp2_driver.driver);
1609 }
1610
1611 static void __exit sbp2_cleanup(void)
1612 {
1613         driver_unregister(&sbp2_driver.driver);
1614         destroy_workqueue(sbp2_wq);
1615 }
1616
1617 module_init(sbp2_init);
1618 module_exit(sbp2_cleanup);