firewire: use split transaction timeout only for split transactions
[linux-2.6.git] / drivers / firewire / sbp2.c
1 /*
2  * SBP2 driver (SCSI over IEEE1394)
3  *
4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 /*
22  * The basic structure of this driver is based on the old storage driver,
23  * drivers/ieee1394/sbp2.c, originally written by
24  *     James Goodwin <jamesg@filanet.com>
25  * with later contributions and ongoing maintenance from
26  *     Ben Collins <bcollins@debian.org>,
27  *     Stefan Richter <stefanr@s5r6.in-berlin.de>
28  * and many others.
29  */
30
31 #include <linux/blkdev.h>
32 #include <linux/bug.h>
33 #include <linux/completion.h>
34 #include <linux/delay.h>
35 #include <linux/device.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/firewire.h>
38 #include <linux/firewire-constants.h>
39 #include <linux/init.h>
40 #include <linux/jiffies.h>
41 #include <linux/kernel.h>
42 #include <linux/kref.h>
43 #include <linux/list.h>
44 #include <linux/mod_devicetable.h>
45 #include <linux/module.h>
46 #include <linux/moduleparam.h>
47 #include <linux/scatterlist.h>
48 #include <linux/slab.h>
49 #include <linux/spinlock.h>
50 #include <linux/string.h>
51 #include <linux/stringify.h>
52 #include <linux/workqueue.h>
53
54 #include <asm/byteorder.h>
55 #include <asm/system.h>
56
57 #include <scsi/scsi.h>
58 #include <scsi/scsi_cmnd.h>
59 #include <scsi/scsi_device.h>
60 #include <scsi/scsi_host.h>
61
62 /*
63  * So far only bridges from Oxford Semiconductor are known to support
64  * concurrent logins. Depending on firmware, four or two concurrent logins
65  * are possible on OXFW911 and newer Oxsemi bridges.
66  *
67  * Concurrent logins are useful together with cluster filesystems.
68  */
69 static int sbp2_param_exclusive_login = 1;
70 module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
71 MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
72                  "(default = Y, use N for concurrent initiators)");
73
74 /*
75  * Flags for firmware oddities
76  *
77  * - 128kB max transfer
78  *   Limit transfer size. Necessary for some old bridges.
79  *
80  * - 36 byte inquiry
81  *   When scsi_mod probes the device, let the inquiry command look like that
82  *   from MS Windows.
83  *
84  * - skip mode page 8
85  *   Suppress sending of mode_sense for mode page 8 if the device pretends to
86  *   support the SCSI Primary Block commands instead of Reduced Block Commands.
87  *
88  * - fix capacity
89  *   Tell sd_mod to correct the last sector number reported by read_capacity.
90  *   Avoids access beyond actual disk limits on devices with an off-by-one bug.
91  *   Don't use this with devices which don't have this bug.
92  *
93  * - delay inquiry
94  *   Wait extra SBP2_INQUIRY_DELAY seconds after login before SCSI inquiry.
95  *
96  * - power condition
97  *   Set the power condition field in the START STOP UNIT commands sent by
98  *   sd_mod on suspend, resume, and shutdown (if manage_start_stop is on).
99  *   Some disks need this to spin down or to resume properly.
100  *
101  * - override internal blacklist
102  *   Instead of adding to the built-in blacklist, use only the workarounds
103  *   specified in the module load parameter.
104  *   Useful if a blacklist entry interfered with a non-broken device.
105  */
106 #define SBP2_WORKAROUND_128K_MAX_TRANS  0x1
107 #define SBP2_WORKAROUND_INQUIRY_36      0x2
108 #define SBP2_WORKAROUND_MODE_SENSE_8    0x4
109 #define SBP2_WORKAROUND_FIX_CAPACITY    0x8
110 #define SBP2_WORKAROUND_DELAY_INQUIRY   0x10
111 #define SBP2_INQUIRY_DELAY              12
112 #define SBP2_WORKAROUND_POWER_CONDITION 0x20
113 #define SBP2_WORKAROUND_OVERRIDE        0x100
114
115 static int sbp2_param_workarounds;
116 module_param_named(workarounds, sbp2_param_workarounds, int, 0644);
117 MODULE_PARM_DESC(workarounds, "Work around device bugs (default = 0"
118         ", 128kB max transfer = " __stringify(SBP2_WORKAROUND_128K_MAX_TRANS)
119         ", 36 byte inquiry = "    __stringify(SBP2_WORKAROUND_INQUIRY_36)
120         ", skip mode page 8 = "   __stringify(SBP2_WORKAROUND_MODE_SENSE_8)
121         ", fix capacity = "       __stringify(SBP2_WORKAROUND_FIX_CAPACITY)
122         ", delay inquiry = "      __stringify(SBP2_WORKAROUND_DELAY_INQUIRY)
123         ", set power condition in start stop unit = "
124                                   __stringify(SBP2_WORKAROUND_POWER_CONDITION)
125         ", override internal blacklist = " __stringify(SBP2_WORKAROUND_OVERRIDE)
126         ", or a combination)");
127
128 /* I don't know why the SCSI stack doesn't define something like this... */
129 typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
130
131 static const char sbp2_driver_name[] = "sbp2";
132
133 /*
134  * We create one struct sbp2_logical_unit per SBP-2 Logical Unit Number Entry
135  * and one struct scsi_device per sbp2_logical_unit.
136  */
137 struct sbp2_logical_unit {
138         struct sbp2_target *tgt;
139         struct list_head link;
140         struct fw_address_handler address_handler;
141         struct list_head orb_list;
142
143         u64 command_block_agent_address;
144         u16 lun;
145         int login_id;
146
147         /*
148          * The generation is updated once we've logged in or reconnected
149          * to the logical unit.  Thus, I/O to the device will automatically
150          * fail and get retried if it happens in a window where the device
151          * is not ready, e.g. after a bus reset but before we reconnect.
152          */
153         int generation;
154         int retries;
155         struct delayed_work work;
156         bool has_sdev;
157         bool blocked;
158 };
159
160 /*
161  * We create one struct sbp2_target per IEEE 1212 Unit Directory
162  * and one struct Scsi_Host per sbp2_target.
163  */
164 struct sbp2_target {
165         struct kref kref;
166         struct fw_unit *unit;
167         const char *bus_id;
168         struct list_head lu_list;
169
170         u64 management_agent_address;
171         u64 guid;
172         int directory_id;
173         int node_id;
174         int address_high;
175         unsigned int workarounds;
176         unsigned int mgt_orb_timeout;
177         unsigned int max_payload;
178
179         int dont_block; /* counter for each logical unit */
180         int blocked;    /* ditto */
181 };
182
183 static struct fw_device *target_device(struct sbp2_target *tgt)
184 {
185         return fw_parent_device(tgt->unit);
186 }
187
188 /* Impossible login_id, to detect logout attempt before successful login */
189 #define INVALID_LOGIN_ID 0x10000
190
191 #define SBP2_ORB_TIMEOUT                2000U           /* Timeout in ms */
192 #define SBP2_ORB_NULL                   0x80000000
193 #define SBP2_RETRY_LIMIT                0xf             /* 15 retries */
194 #define SBP2_CYCLE_LIMIT                (0xc8 << 12)    /* 200 125us cycles */
195
196 /*
197  * There is no transport protocol limit to the CDB length,  but we implement
198  * a fixed length only.  16 bytes is enough for disks larger than 2 TB.
199  */
200 #define SBP2_MAX_CDB_SIZE               16
201
202 /*
203  * The default maximum s/g segment size of a FireWire controller is
204  * usually 0x10000, but SBP-2 only allows 0xffff. Since buffers have to
205  * be quadlet-aligned, we set the length limit to 0xffff & ~3.
206  */
207 #define SBP2_MAX_SEG_SIZE               0xfffc
208
209 /* Unit directory keys */
210 #define SBP2_CSR_UNIT_CHARACTERISTICS   0x3a
211 #define SBP2_CSR_FIRMWARE_REVISION      0x3c
212 #define SBP2_CSR_LOGICAL_UNIT_NUMBER    0x14
213 #define SBP2_CSR_LOGICAL_UNIT_DIRECTORY 0xd4
214
215 /* Management orb opcodes */
216 #define SBP2_LOGIN_REQUEST              0x0
217 #define SBP2_QUERY_LOGINS_REQUEST       0x1
218 #define SBP2_RECONNECT_REQUEST          0x3
219 #define SBP2_SET_PASSWORD_REQUEST       0x4
220 #define SBP2_LOGOUT_REQUEST             0x7
221 #define SBP2_ABORT_TASK_REQUEST         0xb
222 #define SBP2_ABORT_TASK_SET             0xc
223 #define SBP2_LOGICAL_UNIT_RESET         0xe
224 #define SBP2_TARGET_RESET_REQUEST       0xf
225
226 /* Offsets for command block agent registers */
227 #define SBP2_AGENT_STATE                0x00
228 #define SBP2_AGENT_RESET                0x04
229 #define SBP2_ORB_POINTER                0x08
230 #define SBP2_DOORBELL                   0x10
231 #define SBP2_UNSOLICITED_STATUS_ENABLE  0x14
232
233 /* Status write response codes */
234 #define SBP2_STATUS_REQUEST_COMPLETE    0x0
235 #define SBP2_STATUS_TRANSPORT_FAILURE   0x1
236 #define SBP2_STATUS_ILLEGAL_REQUEST     0x2
237 #define SBP2_STATUS_VENDOR_DEPENDENT    0x3
238
239 #define STATUS_GET_ORB_HIGH(v)          ((v).status & 0xffff)
240 #define STATUS_GET_SBP_STATUS(v)        (((v).status >> 16) & 0xff)
241 #define STATUS_GET_LEN(v)               (((v).status >> 24) & 0x07)
242 #define STATUS_GET_DEAD(v)              (((v).status >> 27) & 0x01)
243 #define STATUS_GET_RESPONSE(v)          (((v).status >> 28) & 0x03)
244 #define STATUS_GET_SOURCE(v)            (((v).status >> 30) & 0x03)
245 #define STATUS_GET_ORB_LOW(v)           ((v).orb_low)
246 #define STATUS_GET_DATA(v)              ((v).data)
247
248 struct sbp2_status {
249         u32 status;
250         u32 orb_low;
251         u8 data[24];
252 };
253
254 struct sbp2_pointer {
255         __be32 high;
256         __be32 low;
257 };
258
259 struct sbp2_orb {
260         struct fw_transaction t;
261         struct kref kref;
262         dma_addr_t request_bus;
263         int rcode;
264         struct sbp2_pointer pointer;
265         void (*callback)(struct sbp2_orb * orb, struct sbp2_status * status);
266         struct list_head link;
267 };
268
269 #define MANAGEMENT_ORB_LUN(v)                   ((v))
270 #define MANAGEMENT_ORB_FUNCTION(v)              ((v) << 16)
271 #define MANAGEMENT_ORB_RECONNECT(v)             ((v) << 20)
272 #define MANAGEMENT_ORB_EXCLUSIVE(v)             ((v) ? 1 << 28 : 0)
273 #define MANAGEMENT_ORB_REQUEST_FORMAT(v)        ((v) << 29)
274 #define MANAGEMENT_ORB_NOTIFY                   ((1) << 31)
275
276 #define MANAGEMENT_ORB_RESPONSE_LENGTH(v)       ((v))
277 #define MANAGEMENT_ORB_PASSWORD_LENGTH(v)       ((v) << 16)
278
279 struct sbp2_management_orb {
280         struct sbp2_orb base;
281         struct {
282                 struct sbp2_pointer password;
283                 struct sbp2_pointer response;
284                 __be32 misc;
285                 __be32 length;
286                 struct sbp2_pointer status_fifo;
287         } request;
288         __be32 response[4];
289         dma_addr_t response_bus;
290         struct completion done;
291         struct sbp2_status status;
292 };
293
294 struct sbp2_login_response {
295         __be32 misc;
296         struct sbp2_pointer command_block_agent;
297         __be32 reconnect_hold;
298 };
299 #define COMMAND_ORB_DATA_SIZE(v)        ((v))
300 #define COMMAND_ORB_PAGE_SIZE(v)        ((v) << 16)
301 #define COMMAND_ORB_PAGE_TABLE_PRESENT  ((1) << 19)
302 #define COMMAND_ORB_MAX_PAYLOAD(v)      ((v) << 20)
303 #define COMMAND_ORB_SPEED(v)            ((v) << 24)
304 #define COMMAND_ORB_DIRECTION           ((1) << 27)
305 #define COMMAND_ORB_REQUEST_FORMAT(v)   ((v) << 29)
306 #define COMMAND_ORB_NOTIFY              ((1) << 31)
307
308 struct sbp2_command_orb {
309         struct sbp2_orb base;
310         struct {
311                 struct sbp2_pointer next;
312                 struct sbp2_pointer data_descriptor;
313                 __be32 misc;
314                 u8 command_block[SBP2_MAX_CDB_SIZE];
315         } request;
316         struct scsi_cmnd *cmd;
317         scsi_done_fn_t done;
318         struct sbp2_logical_unit *lu;
319
320         struct sbp2_pointer page_table[SG_ALL] __attribute__((aligned(8)));
321         dma_addr_t page_table_bus;
322 };
323
324 #define SBP2_ROM_VALUE_WILDCARD ~0         /* match all */
325 #define SBP2_ROM_VALUE_MISSING  0xff000000 /* not present in the unit dir. */
326
327 /*
328  * List of devices with known bugs.
329  *
330  * The firmware_revision field, masked with 0xffff00, is the best
331  * indicator for the type of bridge chip of a device.  It yields a few
332  * false positives but this did not break correctly behaving devices
333  * so far.
334  */
335 static const struct {
336         u32 firmware_revision;
337         u32 model;
338         unsigned int workarounds;
339 } sbp2_workarounds_table[] = {
340         /* DViCO Momobay CX-1 with TSB42AA9 bridge */ {
341                 .firmware_revision      = 0x002800,
342                 .model                  = 0x001010,
343                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36 |
344                                           SBP2_WORKAROUND_MODE_SENSE_8 |
345                                           SBP2_WORKAROUND_POWER_CONDITION,
346         },
347         /* DViCO Momobay FX-3A with TSB42AA9A bridge */ {
348                 .firmware_revision      = 0x002800,
349                 .model                  = 0x000000,
350                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
351         },
352         /* Initio bridges, actually only needed for some older ones */ {
353                 .firmware_revision      = 0x000200,
354                 .model                  = SBP2_ROM_VALUE_WILDCARD,
355                 .workarounds            = SBP2_WORKAROUND_INQUIRY_36,
356         },
357         /* PL-3507 bridge with Prolific firmware */ {
358                 .firmware_revision      = 0x012800,
359                 .model                  = SBP2_ROM_VALUE_WILDCARD,
360                 .workarounds            = SBP2_WORKAROUND_POWER_CONDITION,
361         },
362         /* Symbios bridge */ {
363                 .firmware_revision      = 0xa0b800,
364                 .model                  = SBP2_ROM_VALUE_WILDCARD,
365                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
366         },
367         /* Datafab MD2-FW2 with Symbios/LSILogic SYM13FW500 bridge */ {
368                 .firmware_revision      = 0x002600,
369                 .model                  = SBP2_ROM_VALUE_WILDCARD,
370                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS,
371         },
372         /*
373          * iPod 2nd generation: needs 128k max transfer size workaround
374          * iPod 3rd generation: needs fix capacity workaround
375          */
376         {
377                 .firmware_revision      = 0x0a2700,
378                 .model                  = 0x000000,
379                 .workarounds            = SBP2_WORKAROUND_128K_MAX_TRANS |
380                                           SBP2_WORKAROUND_FIX_CAPACITY,
381         },
382         /* iPod 4th generation */ {
383                 .firmware_revision      = 0x0a2700,
384                 .model                  = 0x000021,
385                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
386         },
387         /* iPod mini */ {
388                 .firmware_revision      = 0x0a2700,
389                 .model                  = 0x000022,
390                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
391         },
392         /* iPod mini */ {
393                 .firmware_revision      = 0x0a2700,
394                 .model                  = 0x000023,
395                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
396         },
397         /* iPod Photo */ {
398                 .firmware_revision      = 0x0a2700,
399                 .model                  = 0x00007e,
400                 .workarounds            = SBP2_WORKAROUND_FIX_CAPACITY,
401         }
402 };
403
404 static void free_orb(struct kref *kref)
405 {
406         struct sbp2_orb *orb = container_of(kref, struct sbp2_orb, kref);
407
408         kfree(orb);
409 }
410
411 static void sbp2_status_write(struct fw_card *card, struct fw_request *request,
412                               int tcode, int destination, int source,
413                               int generation, unsigned long long offset,
414                               void *payload, size_t length, void *callback_data)
415 {
416         struct sbp2_logical_unit *lu = callback_data;
417         struct sbp2_orb *orb;
418         struct sbp2_status status;
419         unsigned long flags;
420
421         if (tcode != TCODE_WRITE_BLOCK_REQUEST ||
422             length < 8 || length > sizeof(status)) {
423                 fw_send_response(card, request, RCODE_TYPE_ERROR);
424                 return;
425         }
426
427         status.status  = be32_to_cpup(payload);
428         status.orb_low = be32_to_cpup(payload + 4);
429         memset(status.data, 0, sizeof(status.data));
430         if (length > 8)
431                 memcpy(status.data, payload + 8, length - 8);
432
433         if (STATUS_GET_SOURCE(status) == 2 || STATUS_GET_SOURCE(status) == 3) {
434                 fw_notify("non-orb related status write, not handled\n");
435                 fw_send_response(card, request, RCODE_COMPLETE);
436                 return;
437         }
438
439         /* Lookup the orb corresponding to this status write. */
440         spin_lock_irqsave(&card->lock, flags);
441         list_for_each_entry(orb, &lu->orb_list, link) {
442                 if (STATUS_GET_ORB_HIGH(status) == 0 &&
443                     STATUS_GET_ORB_LOW(status) == orb->request_bus) {
444                         orb->rcode = RCODE_COMPLETE;
445                         list_del(&orb->link);
446                         break;
447                 }
448         }
449         spin_unlock_irqrestore(&card->lock, flags);
450
451         if (&orb->link != &lu->orb_list) {
452                 orb->callback(orb, &status);
453                 kref_put(&orb->kref, free_orb); /* orb callback reference */
454         } else {
455                 fw_error("status write for unknown orb\n");
456         }
457
458         fw_send_response(card, request, RCODE_COMPLETE);
459 }
460
461 static void complete_transaction(struct fw_card *card, int rcode,
462                                  void *payload, size_t length, void *data)
463 {
464         struct sbp2_orb *orb = data;
465         unsigned long flags;
466
467         /*
468          * This is a little tricky.  We can get the status write for
469          * the orb before we get this callback.  The status write
470          * handler above will assume the orb pointer transaction was
471          * successful and set the rcode to RCODE_COMPLETE for the orb.
472          * So this callback only sets the rcode if it hasn't already
473          * been set and only does the cleanup if the transaction
474          * failed and we didn't already get a status write.
475          *
476          * Here we treat RCODE_CANCELLED like RCODE_COMPLETE because some
477          * OXUF936QSE firmwares occasionally respond after Split_Timeout and
478          * complete the ORB just fine.  Note, we also get RCODE_CANCELLED
479          * from sbp2_cancel_orbs() if fw_cancel_transaction() == 0.
480          */
481         spin_lock_irqsave(&card->lock, flags);
482
483         if (orb->rcode == -1)
484                 orb->rcode = rcode;
485
486         if (orb->rcode != RCODE_COMPLETE && orb->rcode != RCODE_CANCELLED) {
487                 list_del(&orb->link);
488                 spin_unlock_irqrestore(&card->lock, flags);
489
490                 orb->callback(orb, NULL);
491                 kref_put(&orb->kref, free_orb); /* orb callback reference */
492         } else {
493                 spin_unlock_irqrestore(&card->lock, flags);
494         }
495
496         kref_put(&orb->kref, free_orb); /* transaction callback reference */
497 }
498
499 static void sbp2_send_orb(struct sbp2_orb *orb, struct sbp2_logical_unit *lu,
500                           int node_id, int generation, u64 offset)
501 {
502         struct fw_device *device = target_device(lu->tgt);
503         unsigned long flags;
504
505         orb->pointer.high = 0;
506         orb->pointer.low = cpu_to_be32(orb->request_bus);
507
508         spin_lock_irqsave(&device->card->lock, flags);
509         list_add_tail(&orb->link, &lu->orb_list);
510         spin_unlock_irqrestore(&device->card->lock, flags);
511
512         kref_get(&orb->kref); /* transaction callback reference */
513         kref_get(&orb->kref); /* orb callback reference */
514
515         fw_send_request(device->card, &orb->t, TCODE_WRITE_BLOCK_REQUEST,
516                         node_id, generation, device->max_speed, offset,
517                         &orb->pointer, 8, complete_transaction, orb);
518 }
519
520 static int sbp2_cancel_orbs(struct sbp2_logical_unit *lu)
521 {
522         struct fw_device *device = target_device(lu->tgt);
523         struct sbp2_orb *orb, *next;
524         struct list_head list;
525         unsigned long flags;
526         int retval = -ENOENT;
527
528         INIT_LIST_HEAD(&list);
529         spin_lock_irqsave(&device->card->lock, flags);
530         list_splice_init(&lu->orb_list, &list);
531         spin_unlock_irqrestore(&device->card->lock, flags);
532
533         list_for_each_entry_safe(orb, next, &list, link) {
534                 retval = 0;
535                 fw_cancel_transaction(device->card, &orb->t);
536
537                 orb->rcode = RCODE_CANCELLED;
538                 orb->callback(orb, NULL);
539                 kref_put(&orb->kref, free_orb); /* orb callback reference */
540         }
541
542         return retval;
543 }
544
545 static void complete_management_orb(struct sbp2_orb *base_orb,
546                                     struct sbp2_status *status)
547 {
548         struct sbp2_management_orb *orb =
549                 container_of(base_orb, struct sbp2_management_orb, base);
550
551         if (status)
552                 memcpy(&orb->status, status, sizeof(*status));
553         complete(&orb->done);
554 }
555
556 static int sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
557                                     int generation, int function,
558                                     int lun_or_login_id, void *response)
559 {
560         struct fw_device *device = target_device(lu->tgt);
561         struct sbp2_management_orb *orb;
562         unsigned int timeout;
563         int retval = -ENOMEM;
564
565         if (function == SBP2_LOGOUT_REQUEST && fw_device_is_shutdown(device))
566                 return 0;
567
568         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
569         if (orb == NULL)
570                 return -ENOMEM;
571
572         kref_init(&orb->base.kref);
573         orb->response_bus =
574                 dma_map_single(device->card->device, &orb->response,
575                                sizeof(orb->response), DMA_FROM_DEVICE);
576         if (dma_mapping_error(device->card->device, orb->response_bus))
577                 goto fail_mapping_response;
578
579         orb->request.response.high = 0;
580         orb->request.response.low  = cpu_to_be32(orb->response_bus);
581
582         orb->request.misc = cpu_to_be32(
583                 MANAGEMENT_ORB_NOTIFY |
584                 MANAGEMENT_ORB_FUNCTION(function) |
585                 MANAGEMENT_ORB_LUN(lun_or_login_id));
586         orb->request.length = cpu_to_be32(
587                 MANAGEMENT_ORB_RESPONSE_LENGTH(sizeof(orb->response)));
588
589         orb->request.status_fifo.high =
590                 cpu_to_be32(lu->address_handler.offset >> 32);
591         orb->request.status_fifo.low  =
592                 cpu_to_be32(lu->address_handler.offset);
593
594         if (function == SBP2_LOGIN_REQUEST) {
595                 /* Ask for 2^2 == 4 seconds reconnect grace period */
596                 orb->request.misc |= cpu_to_be32(
597                         MANAGEMENT_ORB_RECONNECT(2) |
598                         MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login));
599                 timeout = lu->tgt->mgt_orb_timeout;
600         } else {
601                 timeout = SBP2_ORB_TIMEOUT;
602         }
603
604         init_completion(&orb->done);
605         orb->base.callback = complete_management_orb;
606
607         orb->base.request_bus =
608                 dma_map_single(device->card->device, &orb->request,
609                                sizeof(orb->request), DMA_TO_DEVICE);
610         if (dma_mapping_error(device->card->device, orb->base.request_bus))
611                 goto fail_mapping_request;
612
613         sbp2_send_orb(&orb->base, lu, node_id, generation,
614                       lu->tgt->management_agent_address);
615
616         wait_for_completion_timeout(&orb->done, msecs_to_jiffies(timeout));
617
618         retval = -EIO;
619         if (sbp2_cancel_orbs(lu) == 0) {
620                 fw_error("%s: orb reply timed out, rcode=0x%02x\n",
621                          lu->tgt->bus_id, orb->base.rcode);
622                 goto out;
623         }
624
625         if (orb->base.rcode != RCODE_COMPLETE) {
626                 fw_error("%s: management write failed, rcode 0x%02x\n",
627                          lu->tgt->bus_id, orb->base.rcode);
628                 goto out;
629         }
630
631         if (STATUS_GET_RESPONSE(orb->status) != 0 ||
632             STATUS_GET_SBP_STATUS(orb->status) != 0) {
633                 fw_error("%s: error status: %d:%d\n", lu->tgt->bus_id,
634                          STATUS_GET_RESPONSE(orb->status),
635                          STATUS_GET_SBP_STATUS(orb->status));
636                 goto out;
637         }
638
639         retval = 0;
640  out:
641         dma_unmap_single(device->card->device, orb->base.request_bus,
642                          sizeof(orb->request), DMA_TO_DEVICE);
643  fail_mapping_request:
644         dma_unmap_single(device->card->device, orb->response_bus,
645                          sizeof(orb->response), DMA_FROM_DEVICE);
646  fail_mapping_response:
647         if (response)
648                 memcpy(response, orb->response, sizeof(orb->response));
649         kref_put(&orb->base.kref, free_orb);
650
651         return retval;
652 }
653
654 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
655 {
656         struct fw_device *device = target_device(lu->tgt);
657         __be32 d = 0;
658
659         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
660                            lu->tgt->node_id, lu->generation, device->max_speed,
661                            lu->command_block_agent_address + SBP2_AGENT_RESET,
662                            &d, 4);
663 }
664
665 static void complete_agent_reset_write_no_wait(struct fw_card *card,
666                 int rcode, void *payload, size_t length, void *data)
667 {
668         kfree(data);
669 }
670
671 static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
672 {
673         struct fw_device *device = target_device(lu->tgt);
674         struct fw_transaction *t;
675         static __be32 d;
676
677         t = kmalloc(sizeof(*t), GFP_ATOMIC);
678         if (t == NULL)
679                 return;
680
681         fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
682                         lu->tgt->node_id, lu->generation, device->max_speed,
683                         lu->command_block_agent_address + SBP2_AGENT_RESET,
684                         &d, 4, complete_agent_reset_write_no_wait, t);
685 }
686
687 static inline void sbp2_allow_block(struct sbp2_logical_unit *lu)
688 {
689         /*
690          * We may access dont_block without taking card->lock here:
691          * All callers of sbp2_allow_block() and all callers of sbp2_unblock()
692          * are currently serialized against each other.
693          * And a wrong result in sbp2_conditionally_block()'s access of
694          * dont_block is rather harmless, it simply misses its first chance.
695          */
696         --lu->tgt->dont_block;
697 }
698
699 /*
700  * Blocks lu->tgt if all of the following conditions are met:
701  *   - Login, INQUIRY, and high-level SCSI setup of all of the target's
702  *     logical units have been finished (indicated by dont_block == 0).
703  *   - lu->generation is stale.
704  *
705  * Note, scsi_block_requests() must be called while holding card->lock,
706  * otherwise it might foil sbp2_[conditionally_]unblock()'s attempt to
707  * unblock the target.
708  */
709 static void sbp2_conditionally_block(struct sbp2_logical_unit *lu)
710 {
711         struct sbp2_target *tgt = lu->tgt;
712         struct fw_card *card = target_device(tgt)->card;
713         struct Scsi_Host *shost =
714                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
715         unsigned long flags;
716
717         spin_lock_irqsave(&card->lock, flags);
718         if (!tgt->dont_block && !lu->blocked &&
719             lu->generation != card->generation) {
720                 lu->blocked = true;
721                 if (++tgt->blocked == 1)
722                         scsi_block_requests(shost);
723         }
724         spin_unlock_irqrestore(&card->lock, flags);
725 }
726
727 /*
728  * Unblocks lu->tgt as soon as all its logical units can be unblocked.
729  * Note, it is harmless to run scsi_unblock_requests() outside the
730  * card->lock protected section.  On the other hand, running it inside
731  * the section might clash with shost->host_lock.
732  */
733 static void sbp2_conditionally_unblock(struct sbp2_logical_unit *lu)
734 {
735         struct sbp2_target *tgt = lu->tgt;
736         struct fw_card *card = target_device(tgt)->card;
737         struct Scsi_Host *shost =
738                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
739         unsigned long flags;
740         bool unblock = false;
741
742         spin_lock_irqsave(&card->lock, flags);
743         if (lu->blocked && lu->generation == card->generation) {
744                 lu->blocked = false;
745                 unblock = --tgt->blocked == 0;
746         }
747         spin_unlock_irqrestore(&card->lock, flags);
748
749         if (unblock)
750                 scsi_unblock_requests(shost);
751 }
752
753 /*
754  * Prevents future blocking of tgt and unblocks it.
755  * Note, it is harmless to run scsi_unblock_requests() outside the
756  * card->lock protected section.  On the other hand, running it inside
757  * the section might clash with shost->host_lock.
758  */
759 static void sbp2_unblock(struct sbp2_target *tgt)
760 {
761         struct fw_card *card = target_device(tgt)->card;
762         struct Scsi_Host *shost =
763                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
764         unsigned long flags;
765
766         spin_lock_irqsave(&card->lock, flags);
767         ++tgt->dont_block;
768         spin_unlock_irqrestore(&card->lock, flags);
769
770         scsi_unblock_requests(shost);
771 }
772
773 static int sbp2_lun2int(u16 lun)
774 {
775         struct scsi_lun eight_bytes_lun;
776
777         memset(&eight_bytes_lun, 0, sizeof(eight_bytes_lun));
778         eight_bytes_lun.scsi_lun[0] = (lun >> 8) & 0xff;
779         eight_bytes_lun.scsi_lun[1] = lun & 0xff;
780
781         return scsilun_to_int(&eight_bytes_lun);
782 }
783
784 static void sbp2_release_target(struct kref *kref)
785 {
786         struct sbp2_target *tgt = container_of(kref, struct sbp2_target, kref);
787         struct sbp2_logical_unit *lu, *next;
788         struct Scsi_Host *shost =
789                 container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
790         struct scsi_device *sdev;
791         struct fw_device *device = target_device(tgt);
792
793         /* prevent deadlocks */
794         sbp2_unblock(tgt);
795
796         list_for_each_entry_safe(lu, next, &tgt->lu_list, link) {
797                 sdev = scsi_device_lookup(shost, 0, 0, sbp2_lun2int(lu->lun));
798                 if (sdev) {
799                         scsi_remove_device(sdev);
800                         scsi_device_put(sdev);
801                 }
802                 if (lu->login_id != INVALID_LOGIN_ID) {
803                         int generation, node_id;
804                         /*
805                          * tgt->node_id may be obsolete here if we failed
806                          * during initial login or after a bus reset where
807                          * the topology changed.
808                          */
809                         generation = device->generation;
810                         smp_rmb(); /* node_id vs. generation */
811                         node_id    = device->node_id;
812                         sbp2_send_management_orb(lu, node_id, generation,
813                                                  SBP2_LOGOUT_REQUEST,
814                                                  lu->login_id, NULL);
815                 }
816                 fw_core_remove_address_handler(&lu->address_handler);
817                 list_del(&lu->link);
818                 kfree(lu);
819         }
820         scsi_remove_host(shost);
821         fw_notify("released %s, target %d:0:0\n", tgt->bus_id, shost->host_no);
822
823         fw_unit_put(tgt->unit);
824         scsi_host_put(shost);
825         fw_device_put(device);
826 }
827
828 static void sbp2_target_get(struct sbp2_target *tgt)
829 {
830         kref_get(&tgt->kref);
831 }
832
833 static void sbp2_target_put(struct sbp2_target *tgt)
834 {
835         kref_put(&tgt->kref, sbp2_release_target);
836 }
837
838 static struct workqueue_struct *sbp2_wq;
839
840 /*
841  * Always get the target's kref when scheduling work on one its units.
842  * Each workqueue job is responsible to call sbp2_target_put() upon return.
843  */
844 static void sbp2_queue_work(struct sbp2_logical_unit *lu, unsigned long delay)
845 {
846         sbp2_target_get(lu->tgt);
847         if (!queue_delayed_work(sbp2_wq, &lu->work, delay))
848                 sbp2_target_put(lu->tgt);
849 }
850
851 /*
852  * Write retransmit retry values into the BUSY_TIMEOUT register.
853  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
854  *   default retry_limit value is 0 (i.e. never retry transmission). We write a
855  *   saner value after logging into the device.
856  * - The dual-phase retry protocol is optional to implement, and if not
857  *   supported, writes to the dual-phase portion of the register will be
858  *   ignored. We try to write the original 1394-1995 default here.
859  * - In the case of devices that are also SBP-3-compliant, all writes are
860  *   ignored, as the register is read-only, but contains single-phase retry of
861  *   15, which is what we're trying to set for all SBP-2 device anyway, so this
862  *   write attempt is safe and yields more consistent behavior for all devices.
863  *
864  * See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
865  * and section 6.4 of the SBP-3 spec for further details.
866  */
867 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
868 {
869         struct fw_device *device = target_device(lu->tgt);
870         __be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
871
872         fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
873                            lu->tgt->node_id, lu->generation, device->max_speed,
874                            CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &d, 4);
875 }
876
877 static void sbp2_reconnect(struct work_struct *work);
878
879 static void sbp2_login(struct work_struct *work)
880 {
881         struct sbp2_logical_unit *lu =
882                 container_of(work, struct sbp2_logical_unit, work.work);
883         struct sbp2_target *tgt = lu->tgt;
884         struct fw_device *device = target_device(tgt);
885         struct Scsi_Host *shost;
886         struct scsi_device *sdev;
887         struct sbp2_login_response response;
888         int generation, node_id, local_node_id;
889
890         if (fw_device_is_shutdown(device))
891                 goto out;
892
893         generation    = device->generation;
894         smp_rmb();    /* node IDs must not be older than generation */
895         node_id       = device->node_id;
896         local_node_id = device->card->node_id;
897
898         /* If this is a re-login attempt, log out, or we might be rejected. */
899         if (lu->has_sdev)
900                 sbp2_send_management_orb(lu, device->node_id, generation,
901                                 SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
902
903         if (sbp2_send_management_orb(lu, node_id, generation,
904                                 SBP2_LOGIN_REQUEST, lu->lun, &response) < 0) {
905                 if (lu->retries++ < 5) {
906                         sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
907                 } else {
908                         fw_error("%s: failed to login to LUN %04x\n",
909                                  tgt->bus_id, lu->lun);
910                         /* Let any waiting I/O fail from now on. */
911                         sbp2_unblock(lu->tgt);
912                 }
913                 goto out;
914         }
915
916         tgt->node_id      = node_id;
917         tgt->address_high = local_node_id << 16;
918         smp_wmb();        /* node IDs must not be older than generation */
919         lu->generation    = generation;
920
921         lu->command_block_agent_address =
922                 ((u64)(be32_to_cpu(response.command_block_agent.high) & 0xffff)
923                       << 32) | be32_to_cpu(response.command_block_agent.low);
924         lu->login_id = be32_to_cpu(response.misc) & 0xffff;
925
926         fw_notify("%s: logged in to LUN %04x (%d retries)\n",
927                   tgt->bus_id, lu->lun, lu->retries);
928
929         /* set appropriate retry limit(s) in BUSY_TIMEOUT register */
930         sbp2_set_busy_timeout(lu);
931
932         PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
933         sbp2_agent_reset(lu);
934
935         /* This was a re-login. */
936         if (lu->has_sdev) {
937                 sbp2_cancel_orbs(lu);
938                 sbp2_conditionally_unblock(lu);
939                 goto out;
940         }
941
942         if (lu->tgt->workarounds & SBP2_WORKAROUND_DELAY_INQUIRY)
943                 ssleep(SBP2_INQUIRY_DELAY);
944
945         shost = container_of((void *)tgt, struct Scsi_Host, hostdata[0]);
946         sdev = __scsi_add_device(shost, 0, 0, sbp2_lun2int(lu->lun), lu);
947         /*
948          * FIXME:  We are unable to perform reconnects while in sbp2_login().
949          * Therefore __scsi_add_device() will get into trouble if a bus reset
950          * happens in parallel.  It will either fail or leave us with an
951          * unusable sdev.  As a workaround we check for this and retry the
952          * whole login and SCSI probing.
953          */
954
955         /* Reported error during __scsi_add_device() */
956         if (IS_ERR(sdev))
957                 goto out_logout_login;
958
959         /* Unreported error during __scsi_add_device() */
960         smp_rmb(); /* get current card generation */
961         if (generation != device->card->generation) {
962                 scsi_remove_device(sdev);
963                 scsi_device_put(sdev);
964                 goto out_logout_login;
965         }
966
967         /* No error during __scsi_add_device() */
968         lu->has_sdev = true;
969         scsi_device_put(sdev);
970         sbp2_allow_block(lu);
971         goto out;
972
973  out_logout_login:
974         smp_rmb(); /* generation may have changed */
975         generation = device->generation;
976         smp_rmb(); /* node_id must not be older than generation */
977
978         sbp2_send_management_orb(lu, device->node_id, generation,
979                                  SBP2_LOGOUT_REQUEST, lu->login_id, NULL);
980         /*
981          * If a bus reset happened, sbp2_update will have requeued
982          * lu->work already.  Reset the work from reconnect to login.
983          */
984         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
985  out:
986         sbp2_target_put(tgt);
987 }
988
989 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
990 {
991         struct sbp2_logical_unit *lu;
992
993         lu = kmalloc(sizeof(*lu), GFP_KERNEL);
994         if (!lu)
995                 return -ENOMEM;
996
997         lu->address_handler.length           = 0x100;
998         lu->address_handler.address_callback = sbp2_status_write;
999         lu->address_handler.callback_data    = lu;
1000
1001         if (fw_core_add_address_handler(&lu->address_handler,
1002                                         &fw_high_memory_region) < 0) {
1003                 kfree(lu);
1004                 return -ENOMEM;
1005         }
1006
1007         lu->tgt      = tgt;
1008         lu->lun      = lun_entry & 0xffff;
1009         lu->login_id = INVALID_LOGIN_ID;
1010         lu->retries  = 0;
1011         lu->has_sdev = false;
1012         lu->blocked  = false;
1013         ++tgt->dont_block;
1014         INIT_LIST_HEAD(&lu->orb_list);
1015         INIT_DELAYED_WORK(&lu->work, sbp2_login);
1016
1017         list_add_tail(&lu->link, &tgt->lu_list);
1018         return 0;
1019 }
1020
1021 static int sbp2_scan_logical_unit_dir(struct sbp2_target *tgt,
1022                                       const u32 *directory)
1023 {
1024         struct fw_csr_iterator ci;
1025         int key, value;
1026
1027         fw_csr_iterator_init(&ci, directory);
1028         while (fw_csr_iterator_next(&ci, &key, &value))
1029                 if (key == SBP2_CSR_LOGICAL_UNIT_NUMBER &&
1030                     sbp2_add_logical_unit(tgt, value) < 0)
1031                         return -ENOMEM;
1032         return 0;
1033 }
1034
1035 static int sbp2_scan_unit_dir(struct sbp2_target *tgt, const u32 *directory,
1036                               u32 *model, u32 *firmware_revision)
1037 {
1038         struct fw_csr_iterator ci;
1039         int key, value;
1040
1041         fw_csr_iterator_init(&ci, directory);
1042         while (fw_csr_iterator_next(&ci, &key, &value)) {
1043                 switch (key) {
1044
1045                 case CSR_DEPENDENT_INFO | CSR_OFFSET:
1046                         tgt->management_agent_address =
1047                                         CSR_REGISTER_BASE + 4 * value;
1048                         break;
1049
1050                 case CSR_DIRECTORY_ID:
1051                         tgt->directory_id = value;
1052                         break;
1053
1054                 case CSR_MODEL:
1055                         *model = value;
1056                         break;
1057
1058                 case SBP2_CSR_FIRMWARE_REVISION:
1059                         *firmware_revision = value;
1060                         break;
1061
1062                 case SBP2_CSR_UNIT_CHARACTERISTICS:
1063                         /* the timeout value is stored in 500ms units */
1064                         tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500;
1065                         break;
1066
1067                 case SBP2_CSR_LOGICAL_UNIT_NUMBER:
1068                         if (sbp2_add_logical_unit(tgt, value) < 0)
1069                                 return -ENOMEM;
1070                         break;
1071
1072                 case SBP2_CSR_LOGICAL_UNIT_DIRECTORY:
1073                         /* Adjust for the increment in the iterator */
1074                         if (sbp2_scan_logical_unit_dir(tgt, ci.p - 1 + value) < 0)
1075                                 return -ENOMEM;
1076                         break;
1077                 }
1078         }
1079         return 0;
1080 }
1081
1082 /*
1083  * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be
1084  * provided in the config rom. Most devices do provide a value, which
1085  * we'll use for login management orbs, but with some sane limits.
1086  */
1087 static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt)
1088 {
1089         unsigned int timeout = tgt->mgt_orb_timeout;
1090
1091         if (timeout > 40000)
1092                 fw_notify("%s: %ds mgt_ORB_timeout limited to 40s\n",
1093                           tgt->bus_id, timeout / 1000);
1094
1095         tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000);
1096 }
1097
1098 static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model,
1099                                   u32 firmware_revision)
1100 {
1101         int i;
1102         unsigned int w = sbp2_param_workarounds;
1103
1104         if (w)
1105                 fw_notify("Please notify linux1394-devel@lists.sourceforge.net "
1106                           "if you need the workarounds parameter for %s\n",
1107                           tgt->bus_id);
1108
1109         if (w & SBP2_WORKAROUND_OVERRIDE)
1110                 goto out;
1111
1112         for (i = 0; i < ARRAY_SIZE(sbp2_workarounds_table); i++) {
1113
1114                 if (sbp2_workarounds_table[i].firmware_revision !=
1115                     (firmware_revision & 0xffffff00))
1116                         continue;
1117
1118                 if (sbp2_workarounds_table[i].model != model &&
1119                     sbp2_workarounds_table[i].model != SBP2_ROM_VALUE_WILDCARD)
1120                         continue;
1121
1122                 w |= sbp2_workarounds_table[i].workarounds;
1123                 break;
1124         }
1125  out:
1126         if (w)
1127                 fw_notify("Workarounds for %s: 0x%x "
1128                           "(firmware_revision 0x%06x, model_id 0x%06x)\n",
1129                           tgt->bus_id, w, firmware_revision, model);
1130         tgt->workarounds = w;
1131 }
1132
1133 static struct scsi_host_template scsi_driver_template;
1134
1135 static int sbp2_probe(struct device *dev)
1136 {
1137         struct fw_unit *unit = fw_unit(dev);
1138         struct fw_device *device = fw_parent_device(unit);
1139         struct sbp2_target *tgt;
1140         struct sbp2_logical_unit *lu;
1141         struct Scsi_Host *shost;
1142         u32 model, firmware_revision;
1143
1144         if (dma_get_max_seg_size(device->card->device) > SBP2_MAX_SEG_SIZE)
1145                 BUG_ON(dma_set_max_seg_size(device->card->device,
1146                                             SBP2_MAX_SEG_SIZE));
1147
1148         shost = scsi_host_alloc(&scsi_driver_template, sizeof(*tgt));
1149         if (shost == NULL)
1150                 return -ENOMEM;
1151
1152         tgt = (struct sbp2_target *)shost->hostdata;
1153         dev_set_drvdata(&unit->device, tgt);
1154         tgt->unit = unit;
1155         kref_init(&tgt->kref);
1156         INIT_LIST_HEAD(&tgt->lu_list);
1157         tgt->bus_id = dev_name(&unit->device);
1158         tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
1159
1160         if (fw_device_enable_phys_dma(device) < 0)
1161                 goto fail_shost_put;
1162
1163         shost->max_cmd_len = SBP2_MAX_CDB_SIZE;
1164
1165         if (scsi_add_host(shost, &unit->device) < 0)
1166                 goto fail_shost_put;
1167
1168         fw_device_get(device);
1169         fw_unit_get(unit);
1170
1171         /* implicit directory ID */
1172         tgt->directory_id = ((unit->directory - device->config_rom) * 4
1173                              + CSR_CONFIG_ROM) & 0xffffff;
1174
1175         firmware_revision = SBP2_ROM_VALUE_MISSING;
1176         model             = SBP2_ROM_VALUE_MISSING;
1177
1178         if (sbp2_scan_unit_dir(tgt, unit->directory, &model,
1179                                &firmware_revision) < 0)
1180                 goto fail_tgt_put;
1181
1182         sbp2_clamp_management_orb_timeout(tgt);
1183         sbp2_init_workarounds(tgt, model, firmware_revision);
1184
1185         /*
1186          * At S100 we can do 512 bytes per packet, at S200 1024 bytes,
1187          * and so on up to 4096 bytes.  The SBP-2 max_payload field
1188          * specifies the max payload size as 2 ^ (max_payload + 2), so
1189          * if we set this to max_speed + 7, we get the right value.
1190          */
1191         tgt->max_payload = min(device->max_speed + 7, 10U);
1192         tgt->max_payload = min(tgt->max_payload, device->card->max_receive - 1);
1193
1194         /* Do the login in a workqueue so we can easily reschedule retries. */
1195         list_for_each_entry(lu, &tgt->lu_list, link)
1196                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1197         return 0;
1198
1199  fail_tgt_put:
1200         sbp2_target_put(tgt);
1201         return -ENOMEM;
1202
1203  fail_shost_put:
1204         scsi_host_put(shost);
1205         return -ENOMEM;
1206 }
1207
1208 static int sbp2_remove(struct device *dev)
1209 {
1210         struct fw_unit *unit = fw_unit(dev);
1211         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1212
1213         sbp2_target_put(tgt);
1214         return 0;
1215 }
1216
1217 static void sbp2_reconnect(struct work_struct *work)
1218 {
1219         struct sbp2_logical_unit *lu =
1220                 container_of(work, struct sbp2_logical_unit, work.work);
1221         struct sbp2_target *tgt = lu->tgt;
1222         struct fw_device *device = target_device(tgt);
1223         int generation, node_id, local_node_id;
1224
1225         if (fw_device_is_shutdown(device))
1226                 goto out;
1227
1228         generation    = device->generation;
1229         smp_rmb();    /* node IDs must not be older than generation */
1230         node_id       = device->node_id;
1231         local_node_id = device->card->node_id;
1232
1233         if (sbp2_send_management_orb(lu, node_id, generation,
1234                                      SBP2_RECONNECT_REQUEST,
1235                                      lu->login_id, NULL) < 0) {
1236                 /*
1237                  * If reconnect was impossible even though we are in the
1238                  * current generation, fall back and try to log in again.
1239                  *
1240                  * We could check for "Function rejected" status, but
1241                  * looking at the bus generation as simpler and more general.
1242                  */
1243                 smp_rmb(); /* get current card generation */
1244                 if (generation == device->card->generation ||
1245                     lu->retries++ >= 5) {
1246                         fw_error("%s: failed to reconnect\n", tgt->bus_id);
1247                         lu->retries = 0;
1248                         PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
1249                 }
1250                 sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
1251                 goto out;
1252         }
1253
1254         tgt->node_id      = node_id;
1255         tgt->address_high = local_node_id << 16;
1256         smp_wmb();        /* node IDs must not be older than generation */
1257         lu->generation    = generation;
1258
1259         fw_notify("%s: reconnected to LUN %04x (%d retries)\n",
1260                   tgt->bus_id, lu->lun, lu->retries);
1261
1262         sbp2_agent_reset(lu);
1263         sbp2_cancel_orbs(lu);
1264         sbp2_conditionally_unblock(lu);
1265  out:
1266         sbp2_target_put(tgt);
1267 }
1268
1269 static void sbp2_update(struct fw_unit *unit)
1270 {
1271         struct sbp2_target *tgt = dev_get_drvdata(&unit->device);
1272         struct sbp2_logical_unit *lu;
1273
1274         fw_device_enable_phys_dma(fw_parent_device(unit));
1275
1276         /*
1277          * Fw-core serializes sbp2_update() against sbp2_remove().
1278          * Iteration over tgt->lu_list is therefore safe here.
1279          */
1280         list_for_each_entry(lu, &tgt->lu_list, link) {
1281                 sbp2_conditionally_block(lu);
1282                 lu->retries = 0;
1283                 sbp2_queue_work(lu, 0);
1284         }
1285 }
1286
1287 #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e
1288 #define SBP2_SW_VERSION_ENTRY   0x00010483
1289
1290 static const struct ieee1394_device_id sbp2_id_table[] = {
1291         {
1292                 .match_flags  = IEEE1394_MATCH_SPECIFIER_ID |
1293                                 IEEE1394_MATCH_VERSION,
1294                 .specifier_id = SBP2_UNIT_SPEC_ID_ENTRY,
1295                 .version      = SBP2_SW_VERSION_ENTRY,
1296         },
1297         { }
1298 };
1299
1300 static struct fw_driver sbp2_driver = {
1301         .driver   = {
1302                 .owner  = THIS_MODULE,
1303                 .name   = sbp2_driver_name,
1304                 .bus    = &fw_bus_type,
1305                 .probe  = sbp2_probe,
1306                 .remove = sbp2_remove,
1307         },
1308         .update   = sbp2_update,
1309         .id_table = sbp2_id_table,
1310 };
1311
1312 static void sbp2_unmap_scatterlist(struct device *card_device,
1313                                    struct sbp2_command_orb *orb)
1314 {
1315         if (scsi_sg_count(orb->cmd))
1316                 dma_unmap_sg(card_device, scsi_sglist(orb->cmd),
1317                              scsi_sg_count(orb->cmd),
1318                              orb->cmd->sc_data_direction);
1319
1320         if (orb->request.misc & cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT))
1321                 dma_unmap_single(card_device, orb->page_table_bus,
1322                                  sizeof(orb->page_table), DMA_TO_DEVICE);
1323 }
1324
1325 static unsigned int sbp2_status_to_sense_data(u8 *sbp2_status, u8 *sense_data)
1326 {
1327         int sam_status;
1328
1329         sense_data[0] = 0x70;
1330         sense_data[1] = 0x0;
1331         sense_data[2] = sbp2_status[1];
1332         sense_data[3] = sbp2_status[4];
1333         sense_data[4] = sbp2_status[5];
1334         sense_data[5] = sbp2_status[6];
1335         sense_data[6] = sbp2_status[7];
1336         sense_data[7] = 10;
1337         sense_data[8] = sbp2_status[8];
1338         sense_data[9] = sbp2_status[9];
1339         sense_data[10] = sbp2_status[10];
1340         sense_data[11] = sbp2_status[11];
1341         sense_data[12] = sbp2_status[2];
1342         sense_data[13] = sbp2_status[3];
1343         sense_data[14] = sbp2_status[12];
1344         sense_data[15] = sbp2_status[13];
1345
1346         sam_status = sbp2_status[0] & 0x3f;
1347
1348         switch (sam_status) {
1349         case SAM_STAT_GOOD:
1350         case SAM_STAT_CHECK_CONDITION:
1351         case SAM_STAT_CONDITION_MET:
1352         case SAM_STAT_BUSY:
1353         case SAM_STAT_RESERVATION_CONFLICT:
1354         case SAM_STAT_COMMAND_TERMINATED:
1355                 return DID_OK << 16 | sam_status;
1356
1357         default:
1358                 return DID_ERROR << 16;
1359         }
1360 }
1361
1362 static void complete_command_orb(struct sbp2_orb *base_orb,
1363                                  struct sbp2_status *status)
1364 {
1365         struct sbp2_command_orb *orb =
1366                 container_of(base_orb, struct sbp2_command_orb, base);
1367         struct fw_device *device = target_device(orb->lu->tgt);
1368         int result;
1369
1370         if (status != NULL) {
1371                 if (STATUS_GET_DEAD(*status))
1372                         sbp2_agent_reset_no_wait(orb->lu);
1373
1374                 switch (STATUS_GET_RESPONSE(*status)) {
1375                 case SBP2_STATUS_REQUEST_COMPLETE:
1376                         result = DID_OK << 16;
1377                         break;
1378                 case SBP2_STATUS_TRANSPORT_FAILURE:
1379                         result = DID_BUS_BUSY << 16;
1380                         break;
1381                 case SBP2_STATUS_ILLEGAL_REQUEST:
1382                 case SBP2_STATUS_VENDOR_DEPENDENT:
1383                 default:
1384                         result = DID_ERROR << 16;
1385                         break;
1386                 }
1387
1388                 if (result == DID_OK << 16 && STATUS_GET_LEN(*status) > 1)
1389                         result = sbp2_status_to_sense_data(STATUS_GET_DATA(*status),
1390                                                            orb->cmd->sense_buffer);
1391         } else {
1392                 /*
1393                  * If the orb completes with status == NULL, something
1394                  * went wrong, typically a bus reset happened mid-orb
1395                  * or when sending the write (less likely).
1396                  */
1397                 result = DID_BUS_BUSY << 16;
1398                 sbp2_conditionally_block(orb->lu);
1399         }
1400
1401         dma_unmap_single(device->card->device, orb->base.request_bus,
1402                          sizeof(orb->request), DMA_TO_DEVICE);
1403         sbp2_unmap_scatterlist(device->card->device, orb);
1404
1405         orb->cmd->result = result;
1406         orb->done(orb->cmd);
1407 }
1408
1409 static int sbp2_map_scatterlist(struct sbp2_command_orb *orb,
1410                 struct fw_device *device, struct sbp2_logical_unit *lu)
1411 {
1412         struct scatterlist *sg = scsi_sglist(orb->cmd);
1413         int i, n;
1414
1415         n = dma_map_sg(device->card->device, sg, scsi_sg_count(orb->cmd),
1416                        orb->cmd->sc_data_direction);
1417         if (n == 0)
1418                 goto fail;
1419
1420         /*
1421          * Handle the special case where there is only one element in
1422          * the scatter list by converting it to an immediate block
1423          * request. This is also a workaround for broken devices such
1424          * as the second generation iPod which doesn't support page
1425          * tables.
1426          */
1427         if (n == 1) {
1428                 orb->request.data_descriptor.high =
1429                         cpu_to_be32(lu->tgt->address_high);
1430                 orb->request.data_descriptor.low  =
1431                         cpu_to_be32(sg_dma_address(sg));
1432                 orb->request.misc |=
1433                         cpu_to_be32(COMMAND_ORB_DATA_SIZE(sg_dma_len(sg)));
1434                 return 0;
1435         }
1436
1437         for_each_sg(sg, sg, n, i) {
1438                 orb->page_table[i].high = cpu_to_be32(sg_dma_len(sg) << 16);
1439                 orb->page_table[i].low = cpu_to_be32(sg_dma_address(sg));
1440         }
1441
1442         orb->page_table_bus =
1443                 dma_map_single(device->card->device, orb->page_table,
1444                                sizeof(orb->page_table), DMA_TO_DEVICE);
1445         if (dma_mapping_error(device->card->device, orb->page_table_bus))
1446                 goto fail_page_table;
1447
1448         /*
1449          * The data_descriptor pointer is the one case where we need
1450          * to fill in the node ID part of the address.  All other
1451          * pointers assume that the data referenced reside on the
1452          * initiator (i.e. us), but data_descriptor can refer to data
1453          * on other nodes so we need to put our ID in descriptor.high.
1454          */
1455         orb->request.data_descriptor.high = cpu_to_be32(lu->tgt->address_high);
1456         orb->request.data_descriptor.low  = cpu_to_be32(orb->page_table_bus);
1457         orb->request.misc |= cpu_to_be32(COMMAND_ORB_PAGE_TABLE_PRESENT |
1458                                          COMMAND_ORB_DATA_SIZE(n));
1459
1460         return 0;
1461
1462  fail_page_table:
1463         dma_unmap_sg(device->card->device, scsi_sglist(orb->cmd),
1464                      scsi_sg_count(orb->cmd), orb->cmd->sc_data_direction);
1465  fail:
1466         return -ENOMEM;
1467 }
1468
1469 /* SCSI stack integration */
1470
1471 static int sbp2_scsi_queuecommand_lck(struct scsi_cmnd *cmd, scsi_done_fn_t done)
1472 {
1473         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1474         struct fw_device *device = target_device(lu->tgt);
1475         struct sbp2_command_orb *orb;
1476         int generation, retval = SCSI_MLQUEUE_HOST_BUSY;
1477
1478         /*
1479          * Bidirectional commands are not yet implemented, and unknown
1480          * transfer direction not handled.
1481          */
1482         if (cmd->sc_data_direction == DMA_BIDIRECTIONAL) {
1483                 fw_error("Can't handle DMA_BIDIRECTIONAL, rejecting command\n");
1484                 cmd->result = DID_ERROR << 16;
1485                 done(cmd);
1486                 return 0;
1487         }
1488
1489         orb = kzalloc(sizeof(*orb), GFP_ATOMIC);
1490         if (orb == NULL) {
1491                 fw_notify("failed to alloc orb\n");
1492                 return SCSI_MLQUEUE_HOST_BUSY;
1493         }
1494
1495         /* Initialize rcode to something not RCODE_COMPLETE. */
1496         orb->base.rcode = -1;
1497         kref_init(&orb->base.kref);
1498
1499         orb->lu   = lu;
1500         orb->done = done;
1501         orb->cmd  = cmd;
1502
1503         orb->request.next.high = cpu_to_be32(SBP2_ORB_NULL);
1504         orb->request.misc = cpu_to_be32(
1505                 COMMAND_ORB_MAX_PAYLOAD(lu->tgt->max_payload) |
1506                 COMMAND_ORB_SPEED(device->max_speed) |
1507                 COMMAND_ORB_NOTIFY);
1508
1509         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
1510                 orb->request.misc |= cpu_to_be32(COMMAND_ORB_DIRECTION);
1511
1512         generation = device->generation;
1513         smp_rmb();    /* sbp2_map_scatterlist looks at tgt->address_high */
1514
1515         if (scsi_sg_count(cmd) && sbp2_map_scatterlist(orb, device, lu) < 0)
1516                 goto out;
1517
1518         memcpy(orb->request.command_block, cmd->cmnd, cmd->cmd_len);
1519
1520         orb->base.callback = complete_command_orb;
1521         orb->base.request_bus =
1522                 dma_map_single(device->card->device, &orb->request,
1523                                sizeof(orb->request), DMA_TO_DEVICE);
1524         if (dma_mapping_error(device->card->device, orb->base.request_bus)) {
1525                 sbp2_unmap_scatterlist(device->card->device, orb);
1526                 goto out;
1527         }
1528
1529         sbp2_send_orb(&orb->base, lu, lu->tgt->node_id, generation,
1530                       lu->command_block_agent_address + SBP2_ORB_POINTER);
1531         retval = 0;
1532  out:
1533         kref_put(&orb->base.kref, free_orb);
1534         return retval;
1535 }
1536
1537 static DEF_SCSI_QCMD(sbp2_scsi_queuecommand)
1538
1539 static int sbp2_scsi_slave_alloc(struct scsi_device *sdev)
1540 {
1541         struct sbp2_logical_unit *lu = sdev->hostdata;
1542
1543         /* (Re-)Adding logical units via the SCSI stack is not supported. */
1544         if (!lu)
1545                 return -ENOSYS;
1546
1547         sdev->allow_restart = 1;
1548
1549         /* SBP-2 requires quadlet alignment of the data buffers. */
1550         blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
1551
1552         if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
1553                 sdev->inquiry_len = 36;
1554
1555         return 0;
1556 }
1557
1558 static int sbp2_scsi_slave_configure(struct scsi_device *sdev)
1559 {
1560         struct sbp2_logical_unit *lu = sdev->hostdata;
1561
1562         sdev->use_10_for_rw = 1;
1563
1564         if (sbp2_param_exclusive_login)
1565                 sdev->manage_start_stop = 1;
1566
1567         if (sdev->type == TYPE_ROM)
1568                 sdev->use_10_for_ms = 1;
1569
1570         if (sdev->type == TYPE_DISK &&
1571             lu->tgt->workarounds & SBP2_WORKAROUND_MODE_SENSE_8)
1572                 sdev->skip_ms_page_8 = 1;
1573
1574         if (lu->tgt->workarounds & SBP2_WORKAROUND_FIX_CAPACITY)
1575                 sdev->fix_capacity = 1;
1576
1577         if (lu->tgt->workarounds & SBP2_WORKAROUND_POWER_CONDITION)
1578                 sdev->start_stop_pwr_cond = 1;
1579
1580         if (lu->tgt->workarounds & SBP2_WORKAROUND_128K_MAX_TRANS)
1581                 blk_queue_max_hw_sectors(sdev->request_queue, 128 * 1024 / 512);
1582
1583         blk_queue_max_segment_size(sdev->request_queue, SBP2_MAX_SEG_SIZE);
1584
1585         return 0;
1586 }
1587
1588 /*
1589  * Called by scsi stack when something has really gone wrong.  Usually
1590  * called when a command has timed-out for some reason.
1591  */
1592 static int sbp2_scsi_abort(struct scsi_cmnd *cmd)
1593 {
1594         struct sbp2_logical_unit *lu = cmd->device->hostdata;
1595
1596         fw_notify("%s: sbp2_scsi_abort\n", lu->tgt->bus_id);
1597         sbp2_agent_reset(lu);
1598         sbp2_cancel_orbs(lu);
1599
1600         return SUCCESS;
1601 }
1602
1603 /*
1604  * Format of /sys/bus/scsi/devices/.../ieee1394_id:
1605  * u64 EUI-64 : u24 directory_ID : u16 LUN  (all printed in hexadecimal)
1606  *
1607  * This is the concatenation of target port identifier and logical unit
1608  * identifier as per SAM-2...SAM-4 annex A.
1609  */
1610 static ssize_t sbp2_sysfs_ieee1394_id_show(struct device *dev,
1611                         struct device_attribute *attr, char *buf)
1612 {
1613         struct scsi_device *sdev = to_scsi_device(dev);
1614         struct sbp2_logical_unit *lu;
1615
1616         if (!sdev)
1617                 return 0;
1618
1619         lu = sdev->hostdata;
1620
1621         return sprintf(buf, "%016llx:%06x:%04x\n",
1622                         (unsigned long long)lu->tgt->guid,
1623                         lu->tgt->directory_id, lu->lun);
1624 }
1625
1626 static DEVICE_ATTR(ieee1394_id, S_IRUGO, sbp2_sysfs_ieee1394_id_show, NULL);
1627
1628 static struct device_attribute *sbp2_scsi_sysfs_attrs[] = {
1629         &dev_attr_ieee1394_id,
1630         NULL
1631 };
1632
1633 static struct scsi_host_template scsi_driver_template = {
1634         .module                 = THIS_MODULE,
1635         .name                   = "SBP-2 IEEE-1394",
1636         .proc_name              = sbp2_driver_name,
1637         .queuecommand           = sbp2_scsi_queuecommand,
1638         .slave_alloc            = sbp2_scsi_slave_alloc,
1639         .slave_configure        = sbp2_scsi_slave_configure,
1640         .eh_abort_handler       = sbp2_scsi_abort,
1641         .this_id                = -1,
1642         .sg_tablesize           = SG_ALL,
1643         .use_clustering         = ENABLE_CLUSTERING,
1644         .cmd_per_lun            = 1,
1645         .can_queue              = 1,
1646         .sdev_attrs             = sbp2_scsi_sysfs_attrs,
1647 };
1648
1649 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
1650 MODULE_DESCRIPTION("SCSI over IEEE1394");
1651 MODULE_LICENSE("GPL");
1652 MODULE_DEVICE_TABLE(ieee1394, sbp2_id_table);
1653
1654 /* Provide a module alias so root-on-sbp2 initrds don't break. */
1655 #ifndef CONFIG_IEEE1394_SBP2_MODULE
1656 MODULE_ALIAS("sbp2");
1657 #endif
1658
1659 static int __init sbp2_init(void)
1660 {
1661         sbp2_wq = create_singlethread_workqueue(KBUILD_MODNAME);
1662         if (!sbp2_wq)
1663                 return -ENOMEM;
1664
1665         return driver_register(&sbp2_driver.driver);
1666 }
1667
1668 static void __exit sbp2_cleanup(void)
1669 {
1670         driver_unregister(&sbp2_driver.driver);
1671         destroy_workqueue(sbp2_wq);
1672 }
1673
1674 module_init(sbp2_init);
1675 module_exit(sbp2_cleanup);