projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blob
? search:


87ec6458bd1d90531cb0226d0177d0cd0677efe0
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / block / ub.c
1 /*
2 * The low performance USB storage driver (ub).
3 *
4 * Copyright (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
5 * Copyright (C) 2004 Pete Zaitcev (zaitcev@yahoo.com)
6 *
7 * This work is a part of Linux kernel, is derived from it,
8 * and is not licensed separately. See file COPYING for details.
9 *
10 * TODO (sorted by decreasing priority)
11 * -- set readonly flag for CDs, set removable flag for CF readers
12 * -- do inquiry and verify we got a disk and not a tape (for LUN mismatch)
13 * -- verify the 13 conditions and do bulk resets
14 * -- highmem
15 * -- move top_sense and work_bcs into separate allocations (if they survive)
16 * for cache purists and esoteric architectures.
17 * -- Allocate structure for LUN 0 before the first ub_sync_tur, avoid NULL. ?
18 * -- prune comments, they are too volumnous
19 * -- Resove XXX's
20 * -- CLEAR, CLR2STS, CLRRS seem to be ripe for refactoring.
21 */
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/usb.h>
25 #include <linux/usb_usual.h>
26 #include <linux/blkdev.h>
27 #include <linux/timer.h>
28 #include <scsi/scsi.h>
29
30 #define DRV_NAME "ub"
31 #define DEVFS_NAME DRV_NAME
32
33 #define UB_MAJOR 180
34
35 /*
36 * The command state machine is the key model for understanding of this driver.
37 *
38 * The general rule is that all transitions are done towards the bottom
39 * of the diagram, thus preventing any loops.
40 *
41 * An exception to that is how the STAT state is handled. A counter allows it
42 * to be re-entered along the path marked with [C].
43 *
44 * +--------+
45 * ! INIT !
46 * +--------+
47 * !
48 * ub_scsi_cmd_start fails ->--------------------------------------\
49 * ! !
50 * V !
51 * +--------+ !
52 * ! CMD ! !
53 * +--------+ !
54 * ! +--------+ !
55 * was -EPIPE -->-------------------------------->! CLEAR ! !
56 * ! +--------+ !
57 * ! ! !
58 * was error -->------------------------------------- ! --------->\
59 * ! ! !
60 * /--<-- cmd->dir == NONE ? ! !
61 * ! ! ! !
62 * ! V ! !
63 * ! +--------+ ! !
64 * ! ! DATA ! ! !
65 * ! +--------+ ! !
66 * ! ! +---------+ ! !
67 * ! was -EPIPE -->--------------->! CLR2STS ! ! !
68 * ! ! +---------+ ! !
69 * ! ! ! ! !
70 * ! ! was error -->---- ! --------->\
71 * ! was error -->--------------------- ! ------------- ! --------->\
72 * ! ! ! ! !
73 * ! V ! ! !
74 * \--->+--------+ ! ! !
75 * ! STAT !<--------------------------/ ! !
76 * /--->+--------+ ! !
77 * ! ! ! !
78 * [C] was -EPIPE -->-----------\ ! !
79 * ! ! ! ! !
80 * +<---- len == 0 ! ! !
81 * ! ! ! ! !
82 * ! was error -->--------------------------------------!---------->\
83 * ! ! ! ! !
84 * +<---- bad CSW ! ! !
85 * +<---- bad tag ! ! !
86 * ! ! V ! !
87 * ! ! +--------+ ! !
88 * ! ! ! CLRRS ! ! !
89 * ! ! +--------+ ! !
90 * ! ! ! ! !
91 * \------- ! --------------------[C]--------\ ! !
92 * ! ! ! !
93 * cmd->error---\ +--------+ ! !
94 * ! +--------------->! SENSE !<----------/ !
95 * STAT_FAIL----/ +--------+ !
96 * ! ! V
97 * ! V +--------+
98 * \--------------------------------\--------------------->! DONE !
99 * +--------+
100 */
101
102 /*
103 * This many LUNs per USB device.
104 * Every one of them takes a host, see UB_MAX_HOSTS.
105 */
106 #define UB_MAX_LUNS 9
107
108 /*
109 */
110
111 #define UB_PARTS_PER_LUN 8
112
113 #define UB_MAX_CDB_SIZE 16 /* Corresponds to Bulk */
114
115 #define UB_SENSE_SIZE 18
116
117 /*
118 */
119
120 /* command block wrapper */
121 struct bulk_cb_wrap {
122 __le32 Signature; /* contains 'USBC' */
123 u32 Tag; /* unique per command id */
124 __le32 DataTransferLength; /* size of data */
125 u8 Flags; /* direction in bit 0 */
126 u8 Lun; /* LUN */
127 u8 Length; /* of of the CDB */
128 u8 CDB[UB_MAX_CDB_SIZE]; /* max command */
129 };
130
131 #define US_BULK_CB_WRAP_LEN 31
132 #define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */
133 #define US_BULK_FLAG_IN 1
134 #define US_BULK_FLAG_OUT 0
135
136 /* command status wrapper */
137 struct bulk_cs_wrap {
138 __le32 Signature; /* should = 'USBS' */
139 u32 Tag; /* same as original command */
140 __le32 Residue; /* amount not transferred */
141 u8 Status; /* see below */
142 };
143
144 #define US_BULK_CS_WRAP_LEN 13
145 #define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
146 #define US_BULK_STAT_OK 0
147 #define US_BULK_STAT_FAIL 1
148 #define US_BULK_STAT_PHASE 2
149
150 /* bulk-only class specific requests */
151 #define US_BULK_RESET_REQUEST 0xff
152 #define US_BULK_GET_MAX_LUN 0xfe
153
154 /*
155 */
156 struct ub_dev;
157
158 #define UB_MAX_REQ_SG 9 /* cdrecord requires 32KB and maybe a header */
159 #define UB_MAX_SECTORS 64
160
161 /*
162 * A second is more than enough for a 32K transfer (UB_MAX_SECTORS)
163 * even if a webcam hogs the bus, but some devices need time to spin up.
164 */
165 #define UB_URB_TIMEOUT (HZ*2)
166 #define UB_DATA_TIMEOUT (HZ*5) /* ZIP does spin-ups in the data phase */
167 #define UB_STAT_TIMEOUT (HZ*5) /* Same spinups and eject for a dataless cmd. */
168 #define UB_CTRL_TIMEOUT (HZ/2) /* 500ms ought to be enough to clear a stall */
169
170 /*
171 * An instance of a SCSI command in transit.
172 */
173 #define UB_DIR_NONE 0
174 #define UB_DIR_READ 1
175 #define UB_DIR_ILLEGAL2 2
176 #define UB_DIR_WRITE 3
177
178 #define UB_DIR_CHAR(c) (((c)==UB_DIR_WRITE)? 'w': \
179 (((c)==UB_DIR_READ)? 'r': 'n'))
180
181 enum ub_scsi_cmd_state {
182 UB_CMDST_INIT, /* Initial state */
183 UB_CMDST_CMD, /* Command submitted */
184 UB_CMDST_DATA, /* Data phase */
185 UB_CMDST_CLR2STS, /* Clearing before requesting status */
186 UB_CMDST_STAT, /* Status phase */
187 UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */
188 UB_CMDST_CLRRS, /* Clearing before retrying status */
189 UB_CMDST_SENSE, /* Sending Request Sense */
190 UB_CMDST_DONE /* Final state */
191 };
192
193 struct ub_scsi_cmd {
194 unsigned char cdb[UB_MAX_CDB_SIZE];
195 unsigned char cdb_len;
196
197 unsigned char dir; /* 0 - none, 1 - read, 3 - write. */
198 enum ub_scsi_cmd_state state;
199 unsigned int tag;
200 struct ub_scsi_cmd *next;
201
202 int error; /* Return code - valid upon done */
203 unsigned int act_len; /* Return size */
204 unsigned char key, asc, ascq; /* May be valid if error==-EIO */
205
206 int stat_count; /* Retries getting status. */
207
208 unsigned int len; /* Requested length */
209 unsigned int current_sg;
210 unsigned int nsg; /* sgv[nsg] */
211 struct scatterlist sgv[UB_MAX_REQ_SG];
212
213 struct ub_lun *lun;
214 void (*done)(struct ub_dev *, struct ub_scsi_cmd *);
215 void *back;
216 };
217
218 struct ub_request {
219 struct request *rq;
220 unsigned int current_try;
221 unsigned int nsg; /* sgv[nsg] */
222 struct scatterlist sgv[UB_MAX_REQ_SG];
223 };
224
225 /*
226 */
227 struct ub_capacity {
228 unsigned long nsec; /* Linux size - 512 byte sectors */
229 unsigned int bsize; /* Linux hardsect_size */
230 unsigned int bshift; /* Shift between 512 and hard sects */
231 };
232
233 /*
234 * This is a direct take-off from linux/include/completion.h
235 * The difference is that I do not wait on this thing, just poll.
236 * When I want to wait (ub_probe), I just use the stock completion.
237 *
238 * Note that INIT_COMPLETION takes no lock. It is correct. But why
239 * in the bloody hell that thing takes struct instead of pointer to struct
240 * is quite beyond me. I just copied it from the stock completion.
241 */
242 struct ub_completion {
243 unsigned int done;
244 spinlock_t lock;
245 };
246
247 static inline void ub_init_completion(struct ub_completion *x)
248 {
249 x->done = 0;
250 spin_lock_init(&x->lock);
251 }
252
253 #define UB_INIT_COMPLETION(x) ((x).done = 0)
254
255 static void ub_complete(struct ub_completion *x)
256 {
257 unsigned long flags;
258
259 spin_lock_irqsave(&x->lock, flags);
260 x->done++;
261 spin_unlock_irqrestore(&x->lock, flags);
262 }
263
264 static int ub_is_completed(struct ub_completion *x)
265 {
266 unsigned long flags;
267 int ret;
268
269 spin_lock_irqsave(&x->lock, flags);
270 ret = x->done;
271 spin_unlock_irqrestore(&x->lock, flags);
272 return ret;
273 }
274
275 /*
276 */
277 struct ub_scsi_cmd_queue {
278 int qlen, qmax;
279 struct ub_scsi_cmd *head, *tail;
280 };
281
282 /*
283 * The block device instance (one per LUN).
284 */
285 struct ub_lun {
286 struct ub_dev *udev;
287 struct list_head link;
288 struct gendisk *disk;
289 int id; /* Host index */
290 int num; /* LUN number */
291 char name[16];
292
293 int changed; /* Media was changed */
294 int removable;
295 int readonly;
296
297 struct ub_request urq;
298
299 /* Use Ingo's mempool if or when we have more than one command. */
300 /*
301 * Currently we never need more than one command for the whole device.
302 * However, giving every LUN a command is a cheap and automatic way
303 * to enforce fairness between them.
304 */
305 int cmda[1];
306 struct ub_scsi_cmd cmdv[1];
307
308 struct ub_capacity capacity;
309 };
310
311 /*
312 * The USB device instance.
313 */
314 struct ub_dev {
315 spinlock_t *lock;
316 atomic_t poison; /* The USB device is disconnected */
317 int openc; /* protected by ub_lock! */
318 /* kref is too implicit for our taste */
319 int reset; /* Reset is running */
320 unsigned int tagcnt;
321 char name[12];
322 struct usb_device *dev;
323 struct usb_interface *intf;
324
325 struct list_head luns;
326
327 unsigned int send_bulk_pipe; /* cached pipe values */
328 unsigned int recv_bulk_pipe;
329 unsigned int send_ctrl_pipe;
330 unsigned int recv_ctrl_pipe;
331
332 struct tasklet_struct tasklet;
333
334 struct ub_scsi_cmd_queue cmd_queue;
335 struct ub_scsi_cmd top_rqs_cmd; /* REQUEST SENSE */
336 unsigned char top_sense[UB_SENSE_SIZE];
337
338 struct ub_completion work_done;
339 struct urb work_urb;
340 struct timer_list work_timer;
341 int last_pipe; /* What might need clearing */
342 __le32 signature; /* Learned signature */
343 struct bulk_cb_wrap work_bcb;
344 struct bulk_cs_wrap work_bcs;
345 struct usb_ctrlrequest work_cr;
346
347 struct work_struct reset_work;
348 wait_queue_head_t reset_wait;
349
350 int sg_stat[6];
351 };
352
353 /*
354 */
355 static void ub_cleanup(struct ub_dev *sc);
356 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq);
357 static void ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
358 struct ub_scsi_cmd *cmd, struct ub_request *urq);
359 static void ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
360 struct ub_scsi_cmd *cmd, struct ub_request *urq);
361 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
362 static void ub_end_rq(struct request *rq, int uptodate);
363 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
364 struct ub_request *urq, struct ub_scsi_cmd *cmd);
365 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
366 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt);
367 static void ub_scsi_action(unsigned long _dev);
368 static void ub_scsi_dispatch(struct ub_dev *sc);
369 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
370 static void ub_data_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
371 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc);
372 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
373 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
374 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
375 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
376 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
377 int stalled_pipe);
378 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd);
379 static void ub_reset_enter(struct ub_dev *sc, int try);
380 static void ub_reset_task(void *arg);
381 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun);
382 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
383 struct ub_capacity *ret);
384 static int ub_sync_reset(struct ub_dev *sc);
385 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe);
386 static int ub_probe_lun(struct ub_dev *sc, int lnum);
387
388 /*
389 */
390 #ifdef CONFIG_USB_LIBUSUAL
391
392 #define ub_usb_ids storage_usb_ids
393 #else
394
395 static struct usb_device_id ub_usb_ids[] = {
396 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
397 { }
398 };
399
400 MODULE_DEVICE_TABLE(usb, ub_usb_ids);
401 #endif /* CONFIG_USB_LIBUSUAL */
402
403 /*
404 * Find me a way to identify "next free minor" for add_disk(),
405 * and the array disappears the next day. However, the number of
406 * hosts has something to do with the naming and /proc/partitions.
407 * This has to be thought out in detail before changing.
408 * If UB_MAX_HOST was 1000, we'd use a bitmap. Or a better data structure.
409 */
410 #define UB_MAX_HOSTS 26
411 static char ub_hostv[UB_MAX_HOSTS];
412
413 #define UB_QLOCK_NUM 5
414 static spinlock_t ub_qlockv[UB_QLOCK_NUM];
415 static int ub_qlock_next = 0;
416
417 static DEFINE_SPINLOCK(ub_lock); /* Locks globals and ->openc */
418
419 /*
420 * The id allocator.
421 *
422 * This also stores the host for indexing by minor, which is somewhat dirty.
423 */
424 static int ub_id_get(void)
425 {
426 unsigned long flags;
427 int i;
428
429 spin_lock_irqsave(&ub_lock, flags);
430 for (i = 0; i < UB_MAX_HOSTS; i++) {
431 if (ub_hostv[i] == 0) {
432 ub_hostv[i] = 1;
433 spin_unlock_irqrestore(&ub_lock, flags);
434 return i;
435 }
436 }
437 spin_unlock_irqrestore(&ub_lock, flags);
438 return -1;
439 }
440
441 static void ub_id_put(int id)
442 {
443 unsigned long flags;
444
445 if (id < 0 || id >= UB_MAX_HOSTS) {
446 printk(KERN_ERR DRV_NAME ": bad host ID %d\n", id);
447 return;
448 }
449
450 spin_lock_irqsave(&ub_lock, flags);
451 if (ub_hostv[id] == 0) {
452 spin_unlock_irqrestore(&ub_lock, flags);
453 printk(KERN_ERR DRV_NAME ": freeing free host ID %d\n", id);
454 return;
455 }
456 ub_hostv[id] = 0;
457 spin_unlock_irqrestore(&ub_lock, flags);
458 }
459
460 /*
461 * This is necessitated by the fact that blk_cleanup_queue does not
462 * necesserily destroy the queue. Instead, it may merely decrease q->refcnt.
463 * Since our blk_init_queue() passes a spinlock common with ub_dev,
464 * we have life time issues when ub_cleanup frees ub_dev.
465 */
466 static spinlock_t *ub_next_lock(void)
467 {
468 unsigned long flags;
469 spinlock_t *ret;
470
471 spin_lock_irqsave(&ub_lock, flags);
472 ret = &ub_qlockv[ub_qlock_next];
473 ub_qlock_next = (ub_qlock_next + 1) % UB_QLOCK_NUM;
474 spin_unlock_irqrestore(&ub_lock, flags);
475 return ret;
476 }
477
478 /*
479 * Downcount for deallocation. This rides on two assumptions:
480 * - once something is poisoned, its refcount cannot grow
481 * - opens cannot happen at this time (del_gendisk was done)
482 * If the above is true, we can drop the lock, which we need for
483 * blk_cleanup_queue(): the silly thing may attempt to sleep.
484 * [Actually, it never needs to sleep for us, but it calls might_sleep()]
485 */
486 static void ub_put(struct ub_dev *sc)
487 {
488 unsigned long flags;
489
490 spin_lock_irqsave(&ub_lock, flags);
491 --sc->openc;
492 if (sc->openc == 0 && atomic_read(&sc->poison)) {
493 spin_unlock_irqrestore(&ub_lock, flags);
494 ub_cleanup(sc);
495 } else {
496 spin_unlock_irqrestore(&ub_lock, flags);
497 }
498 }
499
500 /*
501 * Final cleanup and deallocation.
502 */
503 static void ub_cleanup(struct ub_dev *sc)
504 {
505 struct list_head *p;
506 struct ub_lun *lun;
507 request_queue_t *q;
508
509 while (!list_empty(&sc->luns)) {
510 p = sc->luns.next;
511 lun = list_entry(p, struct ub_lun, link);
512 list_del(p);
513
514 /* I don't think queue can be NULL. But... Stolen from sx8.c */
515 if ((q = lun->disk->queue) != NULL)
516 blk_cleanup_queue(q);
517 /*
518 * If we zero disk->private_data BEFORE put_disk, we have
519 * to check for NULL all over the place in open, release,
520 * check_media and revalidate, because the block level
521 * semaphore is well inside the put_disk.
522 * But we cannot zero after the call, because *disk is gone.
523 * The sd.c is blatantly racy in this area.
524 */
525 /* disk->private_data = NULL; */
526 put_disk(lun->disk);
527 lun->disk = NULL;
528
529 ub_id_put(lun->id);
530 kfree(lun);
531 }
532
533 usb_set_intfdata(sc->intf, NULL);
534 usb_put_intf(sc->intf);
535 usb_put_dev(sc->dev);
536 kfree(sc);
537 }
538
539 /*
540 * The "command allocator".
541 */
542 static struct ub_scsi_cmd *ub_get_cmd(struct ub_lun *lun)
543 {
544 struct ub_scsi_cmd *ret;
545
546 if (lun->cmda[0])
547 return NULL;
548 ret = &lun->cmdv[0];
549 lun->cmda[0] = 1;
550 return ret;
551 }
552
553 static void ub_put_cmd(struct ub_lun *lun, struct ub_scsi_cmd *cmd)
554 {
555 if (cmd != &lun->cmdv[0]) {
556 printk(KERN_WARNING "%s: releasing a foreign cmd %p\n",
557 lun->name, cmd);
558 return;
559 }
560 if (!lun->cmda[0]) {
561 printk(KERN_WARNING "%s: releasing a free cmd\n", lun->name);
562 return;
563 }
564 lun->cmda[0] = 0;
565 }
566
567 /*
568 * The command queue.
569 */
570 static void ub_cmdq_add(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
571 {
572 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
573
574 if (t->qlen++ == 0) {
575 t->head = cmd;
576 t->tail = cmd;
577 } else {
578 t->tail->next = cmd;
579 t->tail = cmd;
580 }
581
582 if (t->qlen > t->qmax)
583 t->qmax = t->qlen;
584 }
585
586 static void ub_cmdq_insert(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
587 {
588 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
589
590 if (t->qlen++ == 0) {
591 t->head = cmd;
592 t->tail = cmd;
593 } else {
594 cmd->next = t->head;
595 t->head = cmd;
596 }
597
598 if (t->qlen > t->qmax)
599 t->qmax = t->qlen;
600 }
601
602 static struct ub_scsi_cmd *ub_cmdq_pop(struct ub_dev *sc)
603 {
604 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
605 struct ub_scsi_cmd *cmd;
606
607 if (t->qlen == 0)
608 return NULL;
609 if (--t->qlen == 0)
610 t->tail = NULL;
611 cmd = t->head;
612 t->head = cmd->next;
613 cmd->next = NULL;
614 return cmd;
615 }
616
617 #define ub_cmdq_peek(sc) ((sc)->cmd_queue.head)
618
619 /*
620 * The request function is our main entry point
621 */
622
623 static void ub_request_fn(request_queue_t *q)
624 {
625 struct ub_lun *lun = q->queuedata;
626 struct request *rq;
627
628 while ((rq = elv_next_request(q)) != NULL) {
629 if (ub_request_fn_1(lun, rq) != 0) {
630 blk_stop_queue(q);
631 break;
632 }
633 }
634 }
635
636 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq)
637 {
638 struct ub_dev *sc = lun->udev;
639 struct ub_scsi_cmd *cmd;
640 struct ub_request *urq;
641 int n_elem;
642
643 if (atomic_read(&sc->poison) || lun->changed) {
644 blkdev_dequeue_request(rq);
645 ub_end_rq(rq, 0);
646 return 0;
647 }
648
649 if (lun->urq.rq != NULL)
650 return -1;
651 if ((cmd = ub_get_cmd(lun)) == NULL)
652 return -1;
653 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
654
655 blkdev_dequeue_request(rq);
656
657 urq = &lun->urq;
658 memset(urq, 0, sizeof(struct ub_request));
659 urq->rq = rq;
660
661 /*
662 * get scatterlist from block layer
663 */
664 n_elem = blk_rq_map_sg(lun->disk->queue, rq, &urq->sgv[0]);
665 if (n_elem < 0) {
666 /* Impossible, because blk_rq_map_sg should not hit ENOMEM. */
667 printk(KERN_INFO "%s: failed request map (%d)\n",
668 lun->name, n_elem);
669 goto drop;
670 }
671 if (n_elem > UB_MAX_REQ_SG) { /* Paranoia */
672 printk(KERN_WARNING "%s: request with %d segments\n",
673 lun->name, n_elem);
674 goto drop;
675 }
676 urq->nsg = n_elem;
677 sc->sg_stat[n_elem < 5 ? n_elem : 5]++;
678
679 if (blk_pc_request(rq)) {
680 ub_cmd_build_packet(sc, lun, cmd, urq);
681 } else {
682 ub_cmd_build_block(sc, lun, cmd, urq);
683 }
684 cmd->state = UB_CMDST_INIT;
685 cmd->lun = lun;
686 cmd->done = ub_rw_cmd_done;
687 cmd->back = urq;
688
689 cmd->tag = sc->tagcnt++;
690 if (ub_submit_scsi(sc, cmd) != 0)
691 goto drop;
692
693 return 0;
694
695 drop:
696 ub_put_cmd(lun, cmd);
697 ub_end_rq(rq, 0);
698 return 0;
699 }
700
701 static void ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
702 struct ub_scsi_cmd *cmd, struct ub_request *urq)
703 {
704 struct request *rq = urq->rq;
705 unsigned int block, nblks;
706
707 if (rq_data_dir(rq) == WRITE)
708 cmd->dir = UB_DIR_WRITE;
709 else
710 cmd->dir = UB_DIR_READ;
711
712 cmd->nsg = urq->nsg;
713 memcpy(cmd->sgv, urq->sgv, sizeof(struct scatterlist) * cmd->nsg);
714
715 /*
716 * build the command
717 *
718 * The call to blk_queue_hardsect_size() guarantees that request
719 * is aligned, but it is given in terms of 512 byte units, always.
720 */
721 block = rq->sector >> lun->capacity.bshift;
722 nblks = rq->nr_sectors >> lun->capacity.bshift;
723
724 cmd->cdb[0] = (cmd->dir == UB_DIR_READ)? READ_10: WRITE_10;
725 /* 10-byte uses 4 bytes of LBA: 2147483648KB, 2097152MB, 2048GB */
726 cmd->cdb[2] = block >> 24;
727 cmd->cdb[3] = block >> 16;
728 cmd->cdb[4] = block >> 8;
729 cmd->cdb[5] = block;
730 cmd->cdb[7] = nblks >> 8;
731 cmd->cdb[8] = nblks;
732 cmd->cdb_len = 10;
733
734 cmd->len = rq->nr_sectors * 512;
735 }
736
737 static void ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
738 struct ub_scsi_cmd *cmd, struct ub_request *urq)
739 {
740 struct request *rq = urq->rq;
741
742 if (rq->data_len == 0) {
743 cmd->dir = UB_DIR_NONE;
744 } else {
745 if (rq_data_dir(rq) == WRITE)
746 cmd->dir = UB_DIR_WRITE;
747 else
748 cmd->dir = UB_DIR_READ;
749 }
750
751 cmd->nsg = urq->nsg;
752 memcpy(cmd->sgv, urq->sgv, sizeof(struct scatterlist) * cmd->nsg);
753
754 memcpy(&cmd->cdb, rq->cmd, rq->cmd_len);
755 cmd->cdb_len = rq->cmd_len;
756
757 cmd->len = rq->data_len;
758 }
759
760 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
761 {
762 struct ub_lun *lun = cmd->lun;
763 struct ub_request *urq = cmd->back;
764 struct request *rq;
765 int uptodate;
766
767 rq = urq->rq;
768
769 if (cmd->error == 0) {
770 uptodate = 1;
771
772 if (blk_pc_request(rq)) {
773 if (cmd->act_len >= rq->data_len)
774 rq->data_len = 0;
775 else
776 rq->data_len -= cmd->act_len;
777 }
778 } else {
779 uptodate = 0;
780
781 if (blk_pc_request(rq)) {
782 /* UB_SENSE_SIZE is smaller than SCSI_SENSE_BUFFERSIZE */
783 memcpy(rq->sense, sc->top_sense, UB_SENSE_SIZE);
784 rq->sense_len = UB_SENSE_SIZE;
785 if (sc->top_sense[0] != 0)
786 rq->errors = SAM_STAT_CHECK_CONDITION;
787 else
788 rq->errors = DID_ERROR << 16;
789 } else {
790 if (cmd->error == -EIO) {
791 if (ub_rw_cmd_retry(sc, lun, urq, cmd) == 0)
792 return;
793 }
794 }
795 }
796
797 urq->rq = NULL;
798
799 ub_put_cmd(lun, cmd);
800 ub_end_rq(rq, uptodate);
801 blk_start_queue(lun->disk->queue);
802 }
803
804 static void ub_end_rq(struct request *rq, int uptodate)
805 {
806 end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
807 end_that_request_last(rq, uptodate);
808 }
809
810 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,
811 struct ub_request *urq, struct ub_scsi_cmd *cmd)
812 {
813
814 if (atomic_read(&sc->poison))
815 return -ENXIO;
816
817 ub_reset_enter(sc, urq->current_try);
818
819 if (urq->current_try >= 3)
820 return -EIO;
821 urq->current_try++;
822
823 /* Remove this if anyone complains of flooding. */
824 printk(KERN_DEBUG "%s: dir %c len/act %d/%d "
825 "[sense %x %02x %02x] retry %d\n",
826 sc->name, UB_DIR_CHAR(cmd->dir), cmd->len, cmd->act_len,
827 cmd->key, cmd->asc, cmd->ascq, urq->current_try);
828
829 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
830 ub_cmd_build_block(sc, lun, cmd, urq);
831
832 cmd->state = UB_CMDST_INIT;
833 cmd->lun = lun;
834 cmd->done = ub_rw_cmd_done;
835 cmd->back = urq;
836
837 cmd->tag = sc->tagcnt++;
838
839 #if 0 /* Wasteful */
840 return ub_submit_scsi(sc, cmd);
841 #else
842 ub_cmdq_add(sc, cmd);
843 return 0;
844 #endif
845 }
846
847 /*
848 * Submit a regular SCSI operation (not an auto-sense).
849 *
850 * The Iron Law of Good Submit Routine is:
851 * Zero return - callback is done, Nonzero return - callback is not done.
852 * No exceptions.
853 *
854 * Host is assumed locked.
855 */
856 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
857 {
858
859 if (cmd->state != UB_CMDST_INIT ||
860 (cmd->dir != UB_DIR_NONE && cmd->len == 0)) {
861 return -EINVAL;
862 }
863
864 ub_cmdq_add(sc, cmd);
865 /*
866 * We can call ub_scsi_dispatch(sc) right away here, but it's a little
867 * safer to jump to a tasklet, in case upper layers do something silly.
868 */
869 tasklet_schedule(&sc->tasklet);
870 return 0;
871 }
872
873 /*
874 * Submit the first URB for the queued command.
875 * This function does not deal with queueing in any way.
876 */
877 static int ub_scsi_cmd_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
878 {
879 struct bulk_cb_wrap *bcb;
880 int rc;
881
882 bcb = &sc->work_bcb;
883
884 /*
885 * ``If the allocation length is eighteen or greater, and a device
886 * server returns less than eithteen bytes of data, the application
887 * client should assume that the bytes not transferred would have been
888 * zeroes had the device server returned those bytes.''
889 *
890 * We zero sense for all commands so that when a packet request
891 * fails it does not return a stale sense.
892 */
893 memset(&sc->top_sense, 0, UB_SENSE_SIZE);
894
895 /* set up the command wrapper */
896 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
897 bcb->Tag = cmd->tag; /* Endianness is not important */
898 bcb->DataTransferLength = cpu_to_le32(cmd->len);
899 bcb->Flags = (cmd->dir == UB_DIR_READ) ? 0x80 : 0;
900 bcb->Lun = (cmd->lun != NULL) ? cmd->lun->num : 0;
901 bcb->Length = cmd->cdb_len;
902
903 /* copy the command payload */
904 memcpy(bcb->CDB, cmd->cdb, UB_MAX_CDB_SIZE);
905
906 UB_INIT_COMPLETION(sc->work_done);
907
908 sc->last_pipe = sc->send_bulk_pipe;
909 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->send_bulk_pipe,
910 bcb, US_BULK_CB_WRAP_LEN, ub_urb_complete, sc);
911
912 /* Fill what we shouldn't be filling, because usb-storage did so. */
913 sc->work_urb.actual_length = 0;
914 sc->work_urb.error_count = 0;
915 sc->work_urb.status = 0;
916
917 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
918 /* XXX Clear stalls */
919 ub_complete(&sc->work_done);
920 return rc;
921 }
922
923 sc->work_timer.expires = jiffies + UB_URB_TIMEOUT;
924 add_timer(&sc->work_timer);
925
926 cmd->state = UB_CMDST_CMD;
927 return 0;
928 }
929
930 /*
931 * Timeout handler.
932 */
933 static void ub_urb_timeout(unsigned long arg)
934 {
935 struct ub_dev *sc = (struct ub_dev *) arg;
936 unsigned long flags;
937
938 spin_lock_irqsave(sc->lock, flags);
939 if (!ub_is_completed(&sc->work_done))
940 usb_unlink_urb(&sc->work_urb);
941 spin_unlock_irqrestore(sc->lock, flags);
942 }
943
944 /*
945 * Completion routine for the work URB.
946 *
947 * This can be called directly from usb_submit_urb (while we have
948 * the sc->lock taken) and from an interrupt (while we do NOT have
949 * the sc->lock taken). Therefore, bounce this off to a tasklet.
950 */
951 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt)
952 {
953 struct ub_dev *sc = urb->context;
954
955 ub_complete(&sc->work_done);
956 tasklet_schedule(&sc->tasklet);
957 }
958
959 static void ub_scsi_action(unsigned long _dev)
960 {
961 struct ub_dev *sc = (struct ub_dev *) _dev;
962 unsigned long flags;
963
964 spin_lock_irqsave(sc->lock, flags);
965 ub_scsi_dispatch(sc);
966 spin_unlock_irqrestore(sc->lock, flags);
967 }
968
969 static void ub_scsi_dispatch(struct ub_dev *sc)
970 {
971 struct ub_scsi_cmd *cmd;
972 int rc;
973
974 while (!sc->reset && (cmd = ub_cmdq_peek(sc)) != NULL) {
975 if (cmd->state == UB_CMDST_DONE) {
976 ub_cmdq_pop(sc);
977 (*cmd->done)(sc, cmd);
978 } else if (cmd->state == UB_CMDST_INIT) {
979 if ((rc = ub_scsi_cmd_start(sc, cmd)) == 0)
980 break;
981 cmd->error = rc;
982 cmd->state = UB_CMDST_DONE;
983 } else {
984 if (!ub_is_completed(&sc->work_done))
985 break;
986 del_timer(&sc->work_timer);
987 ub_scsi_urb_compl(sc, cmd);
988 }
989 }
990 }
991
992 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
993 {
994 struct urb *urb = &sc->work_urb;
995 struct bulk_cs_wrap *bcs;
996 int len;
997 int rc;
998
999 if (atomic_read(&sc->poison)) {
1000 ub_state_done(sc, cmd, -ENODEV);
1001 return;
1002 }
1003
1004 if (cmd->state == UB_CMDST_CLEAR) {
1005 if (urb->status == -EPIPE) {
1006 /*
1007 * STALL while clearning STALL.
1008 * The control pipe clears itself - nothing to do.
1009 */
1010 printk(KERN_NOTICE "%s: stall on control pipe\n",
1011 sc->name);
1012 goto Bad_End;
1013 }
1014
1015 /*
1016 * We ignore the result for the halt clear.
1017 */
1018
1019 /* reset the endpoint toggle */
1020 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1021 usb_pipeout(sc->last_pipe), 0);
1022
1023 ub_state_sense(sc, cmd);
1024
1025 } else if (cmd->state == UB_CMDST_CLR2STS) {
1026 if (urb->status == -EPIPE) {
1027 printk(KERN_NOTICE "%s: stall on control pipe\n",
1028 sc->name);
1029 goto Bad_End;
1030 }
1031
1032 /*
1033 * We ignore the result for the halt clear.
1034 */
1035
1036 /* reset the endpoint toggle */
1037 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1038 usb_pipeout(sc->last_pipe), 0);
1039
1040 ub_state_stat(sc, cmd);
1041
1042 } else if (cmd->state == UB_CMDST_CLRRS) {
1043 if (urb->status == -EPIPE) {
1044 printk(KERN_NOTICE "%s: stall on control pipe\n",
1045 sc->name);
1046 goto Bad_End;
1047 }
1048
1049 /*
1050 * We ignore the result for the halt clear.
1051 */
1052
1053 /* reset the endpoint toggle */
1054 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1055 usb_pipeout(sc->last_pipe), 0);
1056
1057 ub_state_stat_counted(sc, cmd);
1058
1059 } else if (cmd->state == UB_CMDST_CMD) {
1060 switch (urb->status) {
1061 case 0:
1062 break;
1063 case -EOVERFLOW:
1064 goto Bad_End;
1065 case -EPIPE:
1066 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1067 if (rc != 0) {
1068 printk(KERN_NOTICE "%s: "
1069 "unable to submit clear (%d)\n",
1070 sc->name, rc);
1071 /*
1072 * This is typically ENOMEM or some other such shit.
1073 * Retrying is pointless. Just do Bad End on it...
1074 */
1075 ub_state_done(sc, cmd, rc);
1076 return;
1077 }
1078 cmd->state = UB_CMDST_CLEAR;
1079 return;
1080 case -ESHUTDOWN: /* unplug */
1081 case -EILSEQ: /* unplug timeout on uhci */
1082 ub_state_done(sc, cmd, -ENODEV);
1083 return;
1084 default:
1085 goto Bad_End;
1086 }
1087 if (urb->actual_length != US_BULK_CB_WRAP_LEN) {
1088 goto Bad_End;
1089 }
1090
1091 if (cmd->dir == UB_DIR_NONE || cmd->nsg < 1) {
1092 ub_state_stat(sc, cmd);
1093 return;
1094 }
1095
1096 // udelay(125); // usb-storage has this
1097 ub_data_start(sc, cmd);
1098
1099 } else if (cmd->state == UB_CMDST_DATA) {
1100 if (urb->status == -EPIPE) {
1101 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1102 if (rc != 0) {
1103 printk(KERN_NOTICE "%s: "
1104 "unable to submit clear (%d)\n",
1105 sc->name, rc);
1106 ub_state_done(sc, cmd, rc);
1107 return;
1108 }
1109 cmd->state = UB_CMDST_CLR2STS;
1110 return;
1111 }
1112 if (urb->status == -EOVERFLOW) {
1113 /*
1114 * A babble? Failure, but we must transfer CSW now.
1115 */
1116 cmd->error = -EOVERFLOW; /* A cheap trick... */
1117 ub_state_stat(sc, cmd);
1118 return;
1119 }
1120
1121 if (cmd->dir == UB_DIR_WRITE) {
1122 /*
1123 * Do not continue writes in case of a failure.
1124 * Doing so would cause sectors to be mixed up,
1125 * which is worse than sectors lost.
1126 *
1127 * We must try to read the CSW, or many devices
1128 * get confused.
1129 */
1130 len = urb->actual_length;
1131 if (urb->status != 0 ||
1132 len != cmd->sgv[cmd->current_sg].length) {
1133 cmd->act_len += len;
1134
1135 cmd->error = -EIO;
1136 ub_state_stat(sc, cmd);
1137 return;
1138 }
1139
1140 } else {
1141 /*
1142 * If an error occurs on read, we record it, and
1143 * continue to fetch data in order to avoid bubble.
1144 *
1145 * As a small shortcut, we stop if we detect that
1146 * a CSW mixed into data.
1147 */
1148 if (urb->status != 0)
1149 cmd->error = -EIO;
1150
1151 len = urb->actual_length;
1152 if (urb->status != 0 ||
1153 len != cmd->sgv[cmd->current_sg].length) {
1154 if ((len & 0x1FF) == US_BULK_CS_WRAP_LEN)
1155 goto Bad_End;
1156 }
1157 }
1158
1159 cmd->act_len += urb->actual_length;
1160
1161 if (++cmd->current_sg < cmd->nsg) {
1162 ub_data_start(sc, cmd);
1163 return;
1164 }
1165 ub_state_stat(sc, cmd);
1166
1167 } else if (cmd->state == UB_CMDST_STAT) {
1168 if (urb->status == -EPIPE) {
1169 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1170 if (rc != 0) {
1171 printk(KERN_NOTICE "%s: "
1172 "unable to submit clear (%d)\n",
1173 sc->name, rc);
1174 ub_state_done(sc, cmd, rc);
1175 return;
1176 }
1177
1178 /*
1179 * Having a stall when getting CSW is an error, so
1180 * make sure uppper levels are not oblivious to it.
1181 */
1182 cmd->error = -EIO; /* A cheap trick... */
1183
1184 cmd->state = UB_CMDST_CLRRS;
1185 return;
1186 }
1187
1188 /* Catch everything, including -EOVERFLOW and other nasties. */
1189 if (urb->status != 0)
1190 goto Bad_End;
1191
1192 if (urb->actual_length == 0) {
1193 ub_state_stat_counted(sc, cmd);
1194 return;
1195 }
1196
1197 /*
1198 * Check the returned Bulk protocol status.
1199 * The status block has to be validated first.
1200 */
1201
1202 bcs = &sc->work_bcs;
1203
1204 if (sc->signature == cpu_to_le32(0)) {
1205 /*
1206 * This is the first reply, so do not perform the check.
1207 * Instead, remember the signature the device uses
1208 * for future checks. But do not allow a nul.
1209 */
1210 sc->signature = bcs->Signature;
1211 if (sc->signature == cpu_to_le32(0)) {
1212 ub_state_stat_counted(sc, cmd);
1213 return;
1214 }
1215 } else {
1216 if (bcs->Signature != sc->signature) {
1217 ub_state_stat_counted(sc, cmd);
1218 return;
1219 }
1220 }
1221
1222 if (bcs->Tag != cmd->tag) {
1223 /*
1224 * This usually happens when we disagree with the
1225 * device's microcode about something. For instance,
1226 * a few of them throw this after timeouts. They buffer
1227 * commands and reply at commands we timed out before.
1228 * Without flushing these replies we loop forever.
1229 */
1230 ub_state_stat_counted(sc, cmd);
1231 return;
1232 }
1233
1234 len = le32_to_cpu(bcs->Residue);
1235 if (len != cmd->len - cmd->act_len) {
1236 /*
1237 * It is all right to transfer less, the caller has
1238 * to check. But it's not all right if the device
1239 * counts disagree with our counts.
1240 */
1241 goto Bad_End;
1242 }
1243
1244 switch (bcs->Status) {
1245 case US_BULK_STAT_OK:
1246 break;
1247 case US_BULK_STAT_FAIL:
1248 ub_state_sense(sc, cmd);
1249 return;
1250 case US_BULK_STAT_PHASE:
1251 goto Bad_End;
1252 default:
1253 printk(KERN_INFO "%s: unknown CSW status 0x%x\n",
1254 sc->name, bcs->Status);
1255 ub_state_done(sc, cmd, -EINVAL);
1256 return;
1257 }
1258
1259 /* Not zeroing error to preserve a babble indicator */
1260 if (cmd->error != 0) {
1261 ub_state_sense(sc, cmd);
1262 return;
1263 }
1264 cmd->state = UB_CMDST_DONE;
1265 ub_cmdq_pop(sc);
1266 (*cmd->done)(sc, cmd);
1267
1268 } else if (cmd->state == UB_CMDST_SENSE) {
1269 ub_state_done(sc, cmd, -EIO);
1270
1271 } else {
1272 printk(KERN_WARNING "%s: "
1273 "wrong command state %d\n",
1274 sc->name, cmd->state);
1275 ub_state_done(sc, cmd, -EINVAL);
1276 return;
1277 }
1278 return;
1279
1280 Bad_End: /* Little Excel is dead */
1281 ub_state_done(sc, cmd, -EIO);
1282 }
1283
1284 /*
1285 * Factorization helper for the command state machine:
1286 * Initiate a data segment transfer.
1287 */
1288 static void ub_data_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1289 {
1290 struct scatterlist *sg = &cmd->sgv[cmd->current_sg];
1291 int pipe;
1292 int rc;
1293
1294 UB_INIT_COMPLETION(sc->work_done);
1295
1296 if (cmd->dir == UB_DIR_READ)
1297 pipe = sc->recv_bulk_pipe;
1298 else
1299 pipe = sc->send_bulk_pipe;
1300 sc->last_pipe = pipe;
1301 usb_fill_bulk_urb(&sc->work_urb, sc->dev, pipe,
1302 page_address(sg->page) + sg->offset, sg->length,
1303 ub_urb_complete, sc);
1304 sc->work_urb.actual_length = 0;
1305 sc->work_urb.error_count = 0;
1306 sc->work_urb.status = 0;
1307
1308 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1309 /* XXX Clear stalls */
1310 ub_complete(&sc->work_done);
1311 ub_state_done(sc, cmd, rc);
1312 return;
1313 }
1314
1315 sc->work_timer.expires = jiffies + UB_DATA_TIMEOUT;
1316 add_timer(&sc->work_timer);
1317
1318 cmd->state = UB_CMDST_DATA;
1319 }
1320
1321 /*
1322 * Factorization helper for the command state machine:
1323 * Finish the command.
1324 */
1325 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc)
1326 {
1327
1328 cmd->error = rc;
1329 cmd->state = UB_CMDST_DONE;
1330 ub_cmdq_pop(sc);
1331 (*cmd->done)(sc, cmd);
1332 }
1333
1334 /*
1335 * Factorization helper for the command state machine:
1336 * Submit a CSW read.
1337 */
1338 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1339 {
1340 int rc;
1341
1342 UB_INIT_COMPLETION(sc->work_done);
1343
1344 sc->last_pipe = sc->recv_bulk_pipe;
1345 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->recv_bulk_pipe,
1346 &sc->work_bcs, US_BULK_CS_WRAP_LEN, ub_urb_complete, sc);
1347 sc->work_urb.actual_length = 0;
1348 sc->work_urb.error_count = 0;
1349 sc->work_urb.status = 0;
1350
1351 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1352 /* XXX Clear stalls */
1353 ub_complete(&sc->work_done);
1354 ub_state_done(sc, cmd, rc);
1355 return -1;
1356 }
1357
1358 sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
1359 add_timer(&sc->work_timer);
1360 return 0;
1361 }
1362
1363 /*
1364 * Factorization helper for the command state machine:
1365 * Submit a CSW read and go to STAT state.
1366 */
1367 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1368 {
1369
1370 if (__ub_state_stat(sc, cmd) != 0)
1371 return;
1372
1373 cmd->stat_count = 0;
1374 cmd->state = UB_CMDST_STAT;
1375 }
1376
1377 /*
1378 * Factorization helper for the command state machine:
1379 * Submit a CSW read and go to STAT state with counter (along [C] path).
1380 */
1381 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1382 {
1383
1384 if (++cmd->stat_count >= 4) {
1385 ub_state_sense(sc, cmd);
1386 return;
1387 }
1388
1389 if (__ub_state_stat(sc, cmd) != 0)
1390 return;
1391
1392 cmd->state = UB_CMDST_STAT;
1393 }
1394
1395 /*
1396 * Factorization helper for the command state machine:
1397 * Submit a REQUEST SENSE and go to SENSE state.
1398 */
1399 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1400 {
1401 struct ub_scsi_cmd *scmd;
1402 struct scatterlist *sg;
1403 int rc;
1404
1405 if (cmd->cdb[0] == REQUEST_SENSE) {
1406 rc = -EPIPE;
1407 goto error;
1408 }
1409
1410 scmd = &sc->top_rqs_cmd;
1411 memset(scmd, 0, sizeof(struct ub_scsi_cmd));
1412 scmd->cdb[0] = REQUEST_SENSE;
1413 scmd->cdb[4] = UB_SENSE_SIZE;
1414 scmd->cdb_len = 6;
1415 scmd->dir = UB_DIR_READ;
1416 scmd->state = UB_CMDST_INIT;
1417 scmd->nsg = 1;
1418 sg = &scmd->sgv[0];
1419 sg->page = virt_to_page(sc->top_sense);
1420 sg->offset = (unsigned long)sc->top_sense & (PAGE_SIZE-1);
1421 sg->length = UB_SENSE_SIZE;
1422 scmd->len = UB_SENSE_SIZE;
1423 scmd->lun = cmd->lun;
1424 scmd->done = ub_top_sense_done;
1425 scmd->back = cmd;
1426
1427 scmd->tag = sc->tagcnt++;
1428
1429 cmd->state = UB_CMDST_SENSE;
1430
1431 ub_cmdq_insert(sc, scmd);
1432 return;
1433
1434 error:
1435 ub_state_done(sc, cmd, rc);
1436 }
1437
1438 /*
1439 * A helper for the command's state machine:
1440 * Submit a stall clear.
1441 */
1442 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
1443 int stalled_pipe)
1444 {
1445 int endp;
1446 struct usb_ctrlrequest *cr;
1447 int rc;
1448
1449 endp = usb_pipeendpoint(stalled_pipe);
1450 if (usb_pipein (stalled_pipe))
1451 endp |= USB_DIR_IN;
1452
1453 cr = &sc->work_cr;
1454 cr->bRequestType = USB_RECIP_ENDPOINT;
1455 cr->bRequest = USB_REQ_CLEAR_FEATURE;
1456 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
1457 cr->wIndex = cpu_to_le16(endp);
1458 cr->wLength = cpu_to_le16(0);
1459
1460 UB_INIT_COMPLETION(sc->work_done);
1461
1462 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1463 (unsigned char*) cr, NULL, 0, ub_urb_complete, sc);
1464 sc->work_urb.actual_length = 0;
1465 sc->work_urb.error_count = 0;
1466 sc->work_urb.status = 0;
1467
1468 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1469 ub_complete(&sc->work_done);
1470 return rc;
1471 }
1472
1473 sc->work_timer.expires = jiffies + UB_CTRL_TIMEOUT;
1474 add_timer(&sc->work_timer);
1475 return 0;
1476 }
1477
1478 /*
1479 */
1480 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd)
1481 {
1482 unsigned char *sense = sc->top_sense;
1483 struct ub_scsi_cmd *cmd;
1484
1485 /*
1486 * Find the command which triggered the unit attention or a check,
1487 * save the sense into it, and advance its state machine.
1488 */
1489 if ((cmd = ub_cmdq_peek(sc)) == NULL) {
1490 printk(KERN_WARNING "%s: sense done while idle\n", sc->name);
1491 return;
1492 }
1493 if (cmd != scmd->back) {
1494 printk(KERN_WARNING "%s: "
1495 "sense done for wrong command 0x%x\n",
1496 sc->name, cmd->tag);
1497 return;
1498 }
1499 if (cmd->state != UB_CMDST_SENSE) {
1500 printk(KERN_WARNING "%s: "
1501 "sense done with bad cmd state %d\n",
1502 sc->name, cmd->state);
1503 return;
1504 }
1505
1506 /*
1507 * Ignoring scmd->act_len, because the buffer was pre-zeroed.
1508 */
1509 cmd->key = sense[2] & 0x0F;
1510 cmd->asc = sense[12];
1511 cmd->ascq = sense[13];
1512
1513 ub_scsi_urb_compl(sc, cmd);
1514 }
1515
1516 /*
1517 * Reset management
1518 * XXX Move usb_reset_device to khubd. Hogging kevent is not a good thing.
1519 * XXX Make usb_sync_reset asynchronous.
1520 */
1521
1522 static void ub_reset_enter(struct ub_dev *sc, int try)
1523 {
1524
1525 if (sc->reset) {
1526 /* This happens often on multi-LUN devices. */
1527 return;
1528 }
1529 sc->reset = try + 1;
1530
1531 #if 0 /* Not needed because the disconnect waits for us. */
1532 unsigned long flags;
1533 spin_lock_irqsave(&ub_lock, flags);
1534 sc->openc++;
1535 spin_unlock_irqrestore(&ub_lock, flags);
1536 #endif
1537
1538 #if 0 /* We let them stop themselves. */
1539 struct list_head *p;
1540 struct ub_lun *lun;
1541 list_for_each(p, &sc->luns) {
1542 lun = list_entry(p, struct ub_lun, link);
1543 blk_stop_queue(lun->disk->queue);
1544 }
1545 #endif
1546
1547 schedule_work(&sc->reset_work);
1548 }
1549
1550 static void ub_reset_task(void *arg)
1551 {
1552 struct ub_dev *sc = arg;
1553 unsigned long flags;
1554 struct list_head *p;
1555 struct ub_lun *lun;
1556 int lkr, rc;
1557
1558 if (!sc->reset) {
1559 printk(KERN_WARNING "%s: Running reset unrequested\n",
1560 sc->name);
1561 return;
1562 }
1563
1564 if (atomic_read(&sc->poison)) {
1565 ;
1566 } else if ((sc->reset & 1) == 0) {
1567 ub_sync_reset(sc);
1568 msleep(700); /* usb-storage sleeps 6s (!) */
1569 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
1570 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
1571 } else if (sc->dev->actconfig->desc.bNumInterfaces != 1) {
1572 ;
1573 } else {
1574 if ((lkr = usb_lock_device_for_reset(sc->dev, sc->intf)) < 0) {
1575 printk(KERN_NOTICE
1576 "%s: usb_lock_device_for_reset failed (%d)\n",
1577 sc->name, lkr);
1578 } else {
1579 rc = usb_reset_device(sc->dev);
1580 if (rc < 0) {
1581 printk(KERN_NOTICE "%s: "
1582 "usb_lock_device_for_reset failed (%d)\n",
1583 sc->name, rc);
1584 }
1585
1586 if (lkr)
1587 usb_unlock_device(sc->dev);
1588 }
1589 }
1590
1591 /*
1592 * In theory, no commands can be running while reset is active,
1593 * so nobody can ask for another reset, and so we do not need any
1594 * queues of resets or anything. We do need a spinlock though,
1595 * to interact with block layer.
1596 */
1597 spin_lock_irqsave(sc->lock, flags);
1598 sc->reset = 0;
1599 tasklet_schedule(&sc->tasklet);
1600 list_for_each(p, &sc->luns) {
1601 lun = list_entry(p, struct ub_lun, link);
1602 blk_start_queue(lun->disk->queue);
1603 }
1604 wake_up(&sc->reset_wait);
1605 spin_unlock_irqrestore(sc->lock, flags);
1606 }
1607
1608 /*
1609 * This is called from a process context.
1610 */
1611 static void ub_revalidate(struct ub_dev *sc, struct ub_lun *lun)
1612 {
1613
1614 lun->readonly = 0; /* XXX Query this from the device */
1615
1616 lun->capacity.nsec = 0;
1617 lun->capacity.bsize = 512;
1618 lun->capacity.bshift = 0;
1619
1620 if (ub_sync_tur(sc, lun) != 0)
1621 return; /* Not ready */
1622 lun->changed = 0;
1623
1624 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1625 /*
1626 * The retry here means something is wrong, either with the
1627 * device, with the transport, or with our code.
1628 * We keep this because sd.c has retries for capacity.
1629 */
1630 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1631 lun->capacity.nsec = 0;
1632 lun->capacity.bsize = 512;
1633 lun->capacity.bshift = 0;
1634 }
1635 }
1636 }
1637
1638 /*
1639 * The open funcion.
1640 * This is mostly needed to keep refcounting, but also to support
1641 * media checks on removable media drives.
1642 */
1643 static int ub_bd_open(struct inode *inode, struct file *filp)
1644 {
1645 struct gendisk *disk = inode->i_bdev->bd_disk;
1646 struct ub_lun *lun = disk->private_data;
1647 struct ub_dev *sc = lun->udev;
1648 unsigned long flags;
1649 int rc;
1650
1651 spin_lock_irqsave(&ub_lock, flags);
1652 if (atomic_read(&sc->poison)) {
1653 spin_unlock_irqrestore(&ub_lock, flags);
1654 return -ENXIO;
1655 }
1656 sc->openc++;
1657 spin_unlock_irqrestore(&ub_lock, flags);
1658
1659 if (lun->removable || lun->readonly)
1660 check_disk_change(inode->i_bdev);
1661
1662 /*
1663 * The sd.c considers ->media_present and ->changed not equivalent,
1664 * under some pretty murky conditions (a failure of READ CAPACITY).
1665 * We may need it one day.
1666 */
1667 if (lun->removable && lun->changed && !(filp->f_flags & O_NDELAY)) {
1668 rc = -ENOMEDIUM;
1669 goto err_open;
1670 }
1671
1672 if (lun->readonly && (filp->f_mode & FMODE_WRITE)) {
1673 rc = -EROFS;
1674 goto err_open;
1675 }
1676
1677 return 0;
1678
1679 err_open:
1680 ub_put(sc);
1681 return rc;
1682 }
1683
1684 /*
1685 */
1686 static int ub_bd_release(struct inode *inode, struct file *filp)
1687 {
1688 struct gendisk *disk = inode->i_bdev->bd_disk;
1689 struct ub_lun *lun = disk->private_data;
1690 struct ub_dev *sc = lun->udev;
1691
1692 ub_put(sc);
1693 return 0;
1694 }
1695
1696 /*
1697 * The ioctl interface.
1698 */
1699 static int ub_bd_ioctl(struct inode *inode, struct file *filp,
1700 unsigned int cmd, unsigned long arg)
1701 {
1702 struct gendisk *disk = inode->i_bdev->bd_disk;
1703 void __user *usermem = (void __user *) arg;
1704
1705 return scsi_cmd_ioctl(filp, disk, cmd, usermem);
1706 }
1707
1708 /*
1709 * This is called once a new disk was seen by the block layer or by ub_probe().
1710 * The main onjective here is to discover the features of the media such as
1711 * the capacity, read-only status, etc. USB storage generally does not
1712 * need to be spun up, but if we needed it, this would be the place.
1713 *
1714 * This call can sleep.
1715 *
1716 * The return code is not used.
1717 */
1718 static int ub_bd_revalidate(struct gendisk *disk)
1719 {
1720 struct ub_lun *lun = disk->private_data;
1721
1722 ub_revalidate(lun->udev, lun);
1723
1724 /* XXX Support sector size switching like in sr.c */
1725 blk_queue_hardsect_size(disk->queue, lun->capacity.bsize);
1726 set_capacity(disk, lun->capacity.nsec);
1727 // set_disk_ro(sdkp->disk, lun->readonly);
1728
1729 return 0;
1730 }
1731
1732 /*
1733 * The check is called by the block layer to verify if the media
1734 * is still available. It is supposed to be harmless, lightweight and
1735 * non-intrusive in case the media was not changed.
1736 *
1737 * This call can sleep.
1738 *
1739 * The return code is bool!
1740 */
1741 static int ub_bd_media_changed(struct gendisk *disk)
1742 {
1743 struct ub_lun *lun = disk->private_data;
1744
1745 if (!lun->removable)
1746 return 0;
1747
1748 /*
1749 * We clean checks always after every command, so this is not
1750 * as dangerous as it looks. If the TEST_UNIT_READY fails here,
1751 * the device is actually not ready with operator or software
1752 * intervention required. One dangerous item might be a drive which
1753 * spins itself down, and come the time to write dirty pages, this
1754 * will fail, then block layer discards the data. Since we never
1755 * spin drives up, such devices simply cannot be used with ub anyway.
1756 */
1757 if (ub_sync_tur(lun->udev, lun) != 0) {
1758 lun->changed = 1;
1759 return 1;
1760 }
1761
1762 return lun->changed;
1763 }
1764
1765 static struct block_device_operations ub_bd_fops = {
1766 .owner = THIS_MODULE,
1767 .open = ub_bd_open,
1768 .release = ub_bd_release,
1769 .ioctl = ub_bd_ioctl,
1770 .media_changed = ub_bd_media_changed,
1771 .revalidate_disk = ub_bd_revalidate,
1772 };
1773
1774 /*
1775 * Common ->done routine for commands executed synchronously.
1776 */
1777 static void ub_probe_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1778 {
1779 struct completion *cop = cmd->back;
1780 complete(cop);
1781 }
1782
1783 /*
1784 * Test if the device has a check condition on it, synchronously.
1785 */
1786 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun)
1787 {
1788 struct ub_scsi_cmd *cmd;
1789 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) };
1790 unsigned long flags;
1791 struct completion compl;
1792 int rc;
1793
1794 init_completion(&compl);
1795
1796 rc = -ENOMEM;
1797 if ((cmd = kzalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1798 goto err_alloc;
1799
1800 cmd->cdb[0] = TEST_UNIT_READY;
1801 cmd->cdb_len = 6;
1802 cmd->dir = UB_DIR_NONE;
1803 cmd->state = UB_CMDST_INIT;
1804 cmd->lun = lun; /* This may be NULL, but that's ok */
1805 cmd->done = ub_probe_done;
1806 cmd->back = &compl;
1807
1808 spin_lock_irqsave(sc->lock, flags);
1809 cmd->tag = sc->tagcnt++;
1810
1811 rc = ub_submit_scsi(sc, cmd);
1812 spin_unlock_irqrestore(sc->lock, flags);
1813
1814 if (rc != 0)
1815 goto err_submit;
1816
1817 wait_for_completion(&compl);
1818
1819 rc = cmd->error;
1820
1821 if (rc == -EIO && cmd->key != 0) /* Retries for benh's key */
1822 rc = cmd->key;
1823
1824 err_submit:
1825 kfree(cmd);
1826 err_alloc:
1827 return rc;
1828 }
1829
1830 /*
1831 * Read the SCSI capacity synchronously (for probing).
1832 */
1833 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
1834 struct ub_capacity *ret)
1835 {
1836 struct ub_scsi_cmd *cmd;
1837 struct scatterlist *sg;
1838 char *p;
1839 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) + 8 };
1840 unsigned long flags;
1841 unsigned int bsize, shift;
1842 unsigned long nsec;
1843 struct completion compl;
1844 int rc;
1845
1846 init_completion(&compl);
1847
1848 rc = -ENOMEM;
1849 if ((cmd = kzalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1850 goto err_alloc;
1851 p = (char *)cmd + sizeof(struct ub_scsi_cmd);
1852
1853 cmd->cdb[0] = 0x25;
1854 cmd->cdb_len = 10;
1855 cmd->dir = UB_DIR_READ;
1856 cmd->state = UB_CMDST_INIT;
1857 cmd->nsg = 1;
1858 sg = &cmd->sgv[0];
1859 sg->page = virt_to_page(p);
1860 sg->offset = (unsigned long)p & (PAGE_SIZE-1);
1861 sg->length = 8;
1862 cmd->len = 8;
1863 cmd->lun = lun;
1864 cmd->done = ub_probe_done;
1865 cmd->back = &compl;
1866
1867 spin_lock_irqsave(sc->lock, flags);
1868 cmd->tag = sc->tagcnt++;
1869
1870 rc = ub_submit_scsi(sc, cmd);
1871 spin_unlock_irqrestore(sc->lock, flags);
1872
1873 if (rc != 0)
1874 goto err_submit;
1875
1876 wait_for_completion(&compl);
1877
1878 if (cmd->error != 0) {
1879 rc = -EIO;
1880 goto err_read;
1881 }
1882 if (cmd->act_len != 8) {
1883 rc = -EIO;
1884 goto err_read;
1885 }
1886
1887 /* sd.c special-cases sector size of 0 to mean 512. Needed? Safe? */
1888 nsec = be32_to_cpu(*(__be32 *)p) + 1;
1889 bsize = be32_to_cpu(*(__be32 *)(p + 4));
1890 switch (bsize) {
1891 case 512: shift = 0; break;
1892 case 1024: shift = 1; break;
1893 case 2048: shift = 2; break;
1894 case 4096: shift = 3; break;
1895 default:
1896 rc = -EDOM;
1897 goto err_inv_bsize;
1898 }
1899
1900 ret->bsize = bsize;
1901 ret->bshift = shift;
1902 ret->nsec = nsec << shift;
1903 rc = 0;
1904
1905 err_inv_bsize:
1906 err_read:
1907 err_submit:
1908 kfree(cmd);
1909 err_alloc:
1910 return rc;
1911 }
1912
1913 /*
1914 */
1915 static void ub_probe_urb_complete(struct urb *urb, struct pt_regs *pt)
1916 {
1917 struct completion *cop = urb->context;
1918 complete(cop);
1919 }
1920
1921 static void ub_probe_timeout(unsigned long arg)
1922 {
1923 struct completion *cop = (struct completion *) arg;
1924 complete(cop);
1925 }
1926
1927 /*
1928 * Reset with a Bulk reset.
1929 */
1930 static int ub_sync_reset(struct ub_dev *sc)
1931 {
1932 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
1933 struct usb_ctrlrequest *cr;
1934 struct completion compl;
1935 struct timer_list timer;
1936 int rc;
1937
1938 init_completion(&compl);
1939
1940 cr = &sc->work_cr;
1941 cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
1942 cr->bRequest = US_BULK_RESET_REQUEST;
1943 cr->wValue = cpu_to_le16(0);
1944 cr->wIndex = cpu_to_le16(ifnum);
1945 cr->wLength = cpu_to_le16(0);
1946
1947 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1948 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
1949 sc->work_urb.actual_length = 0;
1950 sc->work_urb.error_count = 0;
1951 sc->work_urb.status = 0;
1952
1953 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
1954 printk(KERN_WARNING
1955 "%s: Unable to submit a bulk reset (%d)\n", sc->name, rc);
1956 return rc;
1957 }
1958
1959 init_timer(&timer);
1960 timer.function = ub_probe_timeout;
1961 timer.data = (unsigned long) &compl;
1962 timer.expires = jiffies + UB_CTRL_TIMEOUT;
1963 add_timer(&timer);
1964
1965 wait_for_completion(&compl);
1966
1967 del_timer_sync(&timer);
1968 usb_kill_urb(&sc->work_urb);
1969
1970 return sc->work_urb.status;
1971 }
1972
1973 /*
1974 * Get number of LUNs by the way of Bulk GetMaxLUN command.
1975 */
1976 static int ub_sync_getmaxlun(struct ub_dev *sc)
1977 {
1978 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
1979 unsigned char *p;
1980 enum { ALLOC_SIZE = 1 };
1981 struct usb_ctrlrequest *cr;
1982 struct completion compl;
1983 struct timer_list timer;
1984 int nluns;
1985 int rc;
1986
1987 init_completion(&compl);
1988
1989 rc = -ENOMEM;
1990 if ((p = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1991 goto err_alloc;
1992 *p = 55;
1993
1994 cr = &sc->work_cr;
1995 cr->bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
1996 cr->bRequest = US_BULK_GET_MAX_LUN;
1997 cr->wValue = cpu_to_le16(0);
1998 cr->wIndex = cpu_to_le16(ifnum);
1999 cr->wLength = cpu_to_le16(1);
2000
2001 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->recv_ctrl_pipe,
2002 (unsigned char*) cr, p, 1, ub_probe_urb_complete, &compl);
2003 sc->work_urb.actual_length = 0;
2004 sc->work_urb.error_count = 0;
2005 sc->work_urb.status = 0;
2006
2007 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0)
2008 goto err_submit;
2009
2010 init_timer(&timer);
2011 timer.function = ub_probe_timeout;
2012 timer.data = (unsigned long) &compl;
2013 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2014 add_timer(&timer);
2015
2016 wait_for_completion(&compl);
2017
2018 del_timer_sync(&timer);
2019 usb_kill_urb(&sc->work_urb);
2020
2021 if ((rc = sc->work_urb.status) < 0)
2022 goto err_io;
2023
2024 if (sc->work_urb.actual_length != 1) {
2025 nluns = 0;
2026 } else {
2027 if ((nluns = *p) == 55) {
2028 nluns = 0;
2029 } else {
2030 /* GetMaxLUN returns the maximum LUN number */
2031 nluns += 1;
2032 if (nluns > UB_MAX_LUNS)
2033 nluns = UB_MAX_LUNS;
2034 }
2035 }
2036
2037 kfree(p);
2038 return nluns;
2039
2040 err_io:
2041 err_submit:
2042 kfree(p);
2043 err_alloc:
2044 return rc;
2045 }
2046
2047 /*
2048 * Clear initial stalls.
2049 */
2050 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe)
2051 {
2052 int endp;
2053 struct usb_ctrlrequest *cr;
2054 struct completion compl;
2055 struct timer_list timer;
2056 int rc;
2057
2058 init_completion(&compl);
2059
2060 endp = usb_pipeendpoint(stalled_pipe);
2061 if (usb_pipein (stalled_pipe))
2062 endp |= USB_DIR_IN;
2063
2064 cr = &sc->work_cr;
2065 cr->bRequestType = USB_RECIP_ENDPOINT;
2066 cr->bRequest = USB_REQ_CLEAR_FEATURE;
2067 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
2068 cr->wIndex = cpu_to_le16(endp);
2069 cr->wLength = cpu_to_le16(0);
2070
2071 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
2072 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
2073 sc->work_urb.actual_length = 0;
2074 sc->work_urb.error_count = 0;
2075 sc->work_urb.status = 0;
2076
2077 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
2078 printk(KERN_WARNING
2079 "%s: Unable to submit a probe clear (%d)\n", sc->name, rc);
2080 return rc;
2081 }
2082
2083 init_timer(&timer);
2084 timer.function = ub_probe_timeout;
2085 timer.data = (unsigned long) &compl;
2086 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2087 add_timer(&timer);
2088
2089 wait_for_completion(&compl);
2090
2091 del_timer_sync(&timer);
2092 usb_kill_urb(&sc->work_urb);
2093
2094 /* reset the endpoint toggle */
2095 usb_settoggle(sc->dev, endp, usb_pipeout(sc->last_pipe), 0);
2096
2097 return 0;
2098 }
2099
2100 /*
2101 * Get the pipe settings.
2102 */
2103 static int ub_get_pipes(struct ub_dev *sc, struct usb_device *dev,
2104 struct usb_interface *intf)
2105 {
2106 struct usb_host_interface *altsetting = intf->cur_altsetting;
2107 struct usb_endpoint_descriptor *ep_in = NULL;
2108 struct usb_endpoint_descriptor *ep_out = NULL;
2109 struct usb_endpoint_descriptor *ep;
2110 int i;
2111
2112 /*
2113 * Find the endpoints we need.
2114 * We are expecting a minimum of 2 endpoints - in and out (bulk).
2115 * We will ignore any others.
2116 */
2117 for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
2118 ep = &altsetting->endpoint[i].desc;
2119
2120 /* Is it a BULK endpoint? */
2121 if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
2122 == USB_ENDPOINT_XFER_BULK) {
2123 /* BULK in or out? */
2124 if (ep->bEndpointAddress & USB_DIR_IN)
2125 ep_in = ep;
2126 else
2127 ep_out = ep;
2128 }
2129 }
2130
2131 if (ep_in == NULL || ep_out == NULL) {
2132 printk(KERN_NOTICE "%s: failed endpoint check\n",
2133 sc->name);
2134 return -ENODEV;
2135 }
2136
2137 /* Calculate and store the pipe values */
2138 sc->send_ctrl_pipe = usb_sndctrlpipe(dev, 0);
2139 sc->recv_ctrl_pipe = usb_rcvctrlpipe(dev, 0);
2140 sc->send_bulk_pipe = usb_sndbulkpipe(dev,
2141 ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2142 sc->recv_bulk_pipe = usb_rcvbulkpipe(dev,
2143 ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2144
2145 return 0;
2146 }
2147
2148 /*
2149 * Probing is done in the process context, which allows us to cheat
2150 * and not to build a state machine for the discovery.
2151 */
2152 static int ub_probe(struct usb_interface *intf,
2153 const struct usb_device_id *dev_id)
2154 {
2155 struct ub_dev *sc;
2156 int nluns;
2157 int rc;
2158 int i;
2159
2160 if (usb_usual_check_type(dev_id, USB_US_TYPE_UB))
2161 return -ENXIO;
2162
2163 rc = -ENOMEM;
2164 if ((sc = kzalloc(sizeof(struct ub_dev), GFP_KERNEL)) == NULL)
2165 goto err_core;
2166 sc->lock = ub_next_lock();
2167 INIT_LIST_HEAD(&sc->luns);
2168 usb_init_urb(&sc->work_urb);
2169 tasklet_init(&sc->tasklet, ub_scsi_action, (unsigned long)sc);
2170 atomic_set(&sc->poison, 0);
2171 INIT_WORK(&sc->reset_work, ub_reset_task, sc);
2172 init_waitqueue_head(&sc->reset_wait);
2173
2174 init_timer(&sc->work_timer);
2175 sc->work_timer.data = (unsigned long) sc;
2176 sc->work_timer.function = ub_urb_timeout;
2177
2178 ub_init_completion(&sc->work_done);
2179 sc->work_done.done = 1; /* A little yuk, but oh well... */
2180
2181 sc->dev = interface_to_usbdev(intf);
2182 sc->intf = intf;
2183 // sc->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2184 usb_set_intfdata(intf, sc);
2185 usb_get_dev(sc->dev);
2186 /*
2187 * Since we give the interface struct to the block level through
2188 * disk->driverfs_dev, we have to pin it. Otherwise, block_uevent
2189 * oopses on close after a disconnect (kernels 2.6.16 and up).
2190 */
2191 usb_get_intf(sc->intf);
2192
2193 snprintf(sc->name, 12, DRV_NAME "(%d.%d)",
2194 sc->dev->bus->busnum, sc->dev->devnum);
2195
2196 /* XXX Verify that we can handle the device (from descriptors) */
2197
2198 if (ub_get_pipes(sc, sc->dev, intf) != 0)
2199 goto err_dev_desc;
2200
2201 /*
2202 * At this point, all USB initialization is done, do upper layer.
2203 * We really hate halfway initialized structures, so from the
2204 * invariants perspective, this ub_dev is fully constructed at
2205 * this point.
2206 */
2207
2208 /*
2209 * This is needed to clear toggles. It is a problem only if we do
2210 * `rmmod ub && modprobe ub` without disconnects, but we like that.
2211 */
2212 #if 0 /* iPod Mini fails if we do this (big white iPod works) */
2213 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
2214 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
2215 #endif
2216
2217 /*
2218 * The way this is used by the startup code is a little specific.
2219 * A SCSI check causes a USB stall. Our common case code sees it
2220 * and clears the check, after which the device is ready for use.
2221 * But if a check was not present, any command other than
2222 * TEST_UNIT_READY ends with a lockup (including REQUEST_SENSE).
2223 *
2224 * If we neglect to clear the SCSI check, the first real command fails
2225 * (which is the capacity readout). We clear that and retry, but why
2226 * causing spurious retries for no reason.
2227 *
2228 * Revalidation may start with its own TEST_UNIT_READY, but that one
2229 * has to succeed, so we clear checks with an additional one here.
2230 * In any case it's not our business how revaliadation is implemented.
2231 */
2232 for (i = 0; i < 3; i++) { /* Retries for the schwag key from KS'04 */
2233 if ((rc = ub_sync_tur(sc, NULL)) <= 0) break;
2234 if (rc != 0x6) break;
2235 msleep(10);
2236 }
2237
2238 nluns = 1;
2239 for (i = 0; i < 3; i++) {
2240 if ((rc = ub_sync_getmaxlun(sc)) < 0)
2241 break;
2242 if (rc != 0) {
2243 nluns = rc;
2244 break;
2245 }
2246 msleep(100);
2247 }
2248
2249 for (i = 0; i < nluns; i++) {
2250 ub_probe_lun(sc, i);
2251 }
2252 return 0;
2253
2254 err_dev_desc:
2255 usb_set_intfdata(intf, NULL);
2256 usb_put_intf(sc->intf);
2257 usb_put_dev(sc->dev);
2258 kfree(sc);
2259 err_core:
2260 return rc;
2261 }
2262
2263 static int ub_probe_lun(struct ub_dev *sc, int lnum)
2264 {
2265 struct ub_lun *lun;
2266 request_queue_t *q;
2267 struct gendisk *disk;
2268 int rc;
2269
2270 rc = -ENOMEM;
2271 if ((lun = kzalloc(sizeof(struct ub_lun), GFP_KERNEL)) == NULL)
2272 goto err_alloc;
2273 lun->num = lnum;
2274
2275 rc = -ENOSR;
2276 if ((lun->id = ub_id_get()) == -1)
2277 goto err_id;
2278
2279 lun->udev = sc;
2280
2281 snprintf(lun->name, 16, DRV_NAME "%c(%d.%d.%d)",
2282 lun->id + 'a', sc->dev->bus->busnum, sc->dev->devnum, lun->num);
2283
2284 lun->removable = 1; /* XXX Query this from the device */
2285 lun->changed = 1; /* ub_revalidate clears only */
2286 ub_revalidate(sc, lun);
2287
2288 rc = -ENOMEM;
2289 if ((disk = alloc_disk(UB_PARTS_PER_LUN)) == NULL)
2290 goto err_diskalloc;
2291
2292 sprintf(disk->disk_name, DRV_NAME "%c", lun->id + 'a');
2293 sprintf(disk->devfs_name, DEVFS_NAME "/%c", lun->id + 'a');
2294 disk->major = UB_MAJOR;
2295 disk->first_minor = lun->id * UB_PARTS_PER_LUN;
2296 disk->fops = &ub_bd_fops;
2297 disk->private_data = lun;
2298 disk->driverfs_dev = &sc->intf->dev;
2299
2300 rc = -ENOMEM;
2301 if ((q = blk_init_queue(ub_request_fn, sc->lock)) == NULL)
2302 goto err_blkqinit;
2303
2304 disk->queue = q;
2305
2306 blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
2307 blk_queue_max_hw_segments(q, UB_MAX_REQ_SG);
2308 blk_queue_max_phys_segments(q, UB_MAX_REQ_SG);
2309 blk_queue_segment_boundary(q, 0xffffffff); /* Dubious. */
2310 blk_queue_max_sectors(q, UB_MAX_SECTORS);
2311 blk_queue_hardsect_size(q, lun->capacity.bsize);
2312
2313 lun->disk = disk;
2314 q->queuedata = lun;
2315 list_add(&lun->link, &sc->luns);
2316
2317 set_capacity(disk, lun->capacity.nsec);
2318 if (lun->removable)
2319 disk->flags |= GENHD_FL_REMOVABLE;
2320
2321 add_disk(disk);
2322
2323 return 0;
2324
2325 err_blkqinit:
2326 put_disk(disk);
2327 err_diskalloc:
2328 ub_id_put(lun->id);
2329 err_id:
2330 kfree(lun);
2331 err_alloc:
2332 return rc;
2333 }
2334
2335 static void ub_disconnect(struct usb_interface *intf)
2336 {
2337 struct ub_dev *sc = usb_get_intfdata(intf);
2338 struct list_head *p;
2339 struct ub_lun *lun;
2340 unsigned long flags;
2341
2342 /*
2343 * Prevent ub_bd_release from pulling the rug from under us.
2344 * XXX This is starting to look like a kref.
2345 * XXX Why not to take this ref at probe time?
2346 */
2347 spin_lock_irqsave(&ub_lock, flags);
2348 sc->openc++;
2349 spin_unlock_irqrestore(&ub_lock, flags);
2350
2351 /*
2352 * Fence stall clearnings, operations triggered by unlinkings and so on.
2353 * We do not attempt to unlink any URBs, because we do not trust the
2354 * unlink paths in HC drivers. Also, we get -84 upon disconnect anyway.
2355 */
2356 atomic_set(&sc->poison, 1);
2357
2358 /*
2359 * Wait for reset to end, if any.
2360 */
2361 wait_event(sc->reset_wait, !sc->reset);
2362
2363 /*
2364 * Blow away queued commands.
2365 *
2366 * Actually, this never works, because before we get here
2367 * the HCD terminates outstanding URB(s). It causes our
2368 * SCSI command queue to advance, commands fail to submit,
2369 * and the whole queue drains. So, we just use this code to
2370 * print warnings.
2371 */
2372 spin_lock_irqsave(sc->lock, flags);
2373 {
2374 struct ub_scsi_cmd *cmd;
2375 int cnt = 0;
2376 while ((cmd = ub_cmdq_peek(sc)) != NULL) {
2377 cmd->error = -ENOTCONN;
2378 cmd->state = UB_CMDST_DONE;
2379 ub_cmdq_pop(sc);
2380 (*cmd->done)(sc, cmd);
2381 cnt++;
2382 }
2383 if (cnt != 0) {
2384 printk(KERN_WARNING "%s: "
2385 "%d was queued after shutdown\n", sc->name, cnt);
2386 }
2387 }
2388 spin_unlock_irqrestore(sc->lock, flags);
2389
2390 /*
2391 * Unregister the upper layer.
2392 */
2393 list_for_each (p, &sc->luns) {
2394 lun = list_entry(p, struct ub_lun, link);
2395 del_gendisk(lun->disk);
2396 /*
2397 * I wish I could do:
2398 * set_bit(QUEUE_FLAG_DEAD, &q->queue_flags);
2399 * As it is, we rely on our internal poisoning and let
2400 * the upper levels to spin furiously failing all the I/O.
2401 */
2402 }
2403
2404 /*
2405 * Testing for -EINPROGRESS is always a bug, so we are bending
2406 * the rules a little.
2407 */
2408 spin_lock_irqsave(sc->lock, flags);
2409 if (sc->work_urb.status == -EINPROGRESS) { /* janitors: ignore */
2410 printk(KERN_WARNING "%s: "
2411 "URB is active after disconnect\n", sc->name);
2412 }
2413 spin_unlock_irqrestore(sc->lock, flags);
2414
2415 /*
2416 * There is virtually no chance that other CPU runs times so long
2417 * after ub_urb_complete should have called del_timer, but only if HCD
2418 * didn't forget to deliver a callback on unlink.
2419 */
2420 del_timer_sync(&sc->work_timer);
2421
2422 /*
2423 * At this point there must be no commands coming from anyone
2424 * and no URBs left in transit.
2425 */
2426
2427 ub_put(sc);
2428 }
2429
2430 static struct usb_driver ub_driver = {
2431 .name = "ub",
2432 .probe = ub_probe,
2433 .disconnect = ub_disconnect,
2434 .id_table = ub_usb_ids,
2435 };
2436
2437 static int __init ub_init(void)
2438 {
2439 int rc;
2440 int i;
2441
2442 for (i = 0; i < UB_QLOCK_NUM; i++)
2443 spin_lock_init(&ub_qlockv[i]);
2444
2445 if ((rc = register_blkdev(UB_MAJOR, DRV_NAME)) != 0)
2446 goto err_regblkdev;
2447
2448 if ((rc = usb_register(&ub_driver)) != 0)
2449 goto err_register;
2450
2451 usb_usual_set_present(USB_US_TYPE_UB);
2452 return 0;
2453
2454 err_register:
2455 unregister_blkdev(UB_MAJOR, DRV_NAME);
2456 err_regblkdev:
2457 return rc;
2458 }
2459
2460 static void __exit ub_exit(void)
2461 {
2462 usb_deregister(&ub_driver);
2463
2464 unregister_blkdev(UB_MAJOR, DRV_NAME);
2465 usb_usual_clear_present(USB_US_TYPE_UB);
2466 }
2467
2468 module_init(ub_init);
2469 module_exit(ub_exit);
2470
2471 MODULE_LICENSE("GPL");
kernel source for telekom puls (alcatel/mediatek)