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[PATCH] USB: ub 3/3: death to ub_bd_rq_fn_1
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / block / ub.c
blob692553270401028c954aa73baf2b804ac40d9120
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 * -- Kill first_open (Al Viro fixed the block layer now)
12 * -- Do resets with usb_device_reset (needs a thread context, use khubd)
13 * -- set readonly flag for CDs, set removable flag for CF readers
14 * -- do inquiry and verify we got a disk and not a tape (for LUN mismatch)
15 * -- special case some senses, e.g. 3a/0 -> no media present, reduce retries
16 * -- verify the 13 conditions and do bulk resets
17 * -- kill last_pipe and simply do two-state clearing on both pipes
18 * -- verify protocol (bulk) from USB descriptors (maybe...)
19 * -- highmem
20 * -- move top_sense and work_bcs into separate allocations (if they survive)
21 * for cache purists and esoteric architectures.
22 * -- Allocate structure for LUN 0 before the first ub_sync_tur, avoid NULL. ?
23 * -- prune comments, they are too volumnous
24 * -- Exterminate P3 printks
25 * -- Resove XXX's
26 * -- Redo "benh's retries", perhaps have spin-up code to handle them. V:D=?
27 * -- CLEAR, CLR2STS, CLRRS seem to be ripe for refactoring.
28 */
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/usb.h>
32 #include <linux/blkdev.h>
33 #include <linux/devfs_fs_kernel.h>
34 #include <linux/timer.h>
35 #include <scsi/scsi.h>
36
37 #define DRV_NAME "ub"
38 #define DEVFS_NAME DRV_NAME
39
40 #define UB_MAJOR 180
41
42 /*
43 * The command state machine is the key model for understanding of this driver.
44 *
45 * The general rule is that all transitions are done towards the bottom
46 * of the diagram, thus preventing any loops.
47 *
48 * An exception to that is how the STAT state is handled. A counter allows it
49 * to be re-entered along the path marked with [C].
50 *
51 * +--------+
52 * ! INIT !
53 * +--------+
54 * !
55 * ub_scsi_cmd_start fails ->--------------------------------------\
56 * ! !
57 * V !
58 * +--------+ !
59 * ! CMD ! !
60 * +--------+ !
61 * ! +--------+ !
62 * was -EPIPE -->-------------------------------->! CLEAR ! !
63 * ! +--------+ !
64 * ! ! !
65 * was error -->------------------------------------- ! --------->\
66 * ! ! !
67 * /--<-- cmd->dir == NONE ? ! !
68 * ! ! ! !
69 * ! V ! !
70 * ! +--------+ ! !
71 * ! ! DATA ! ! !
72 * ! +--------+ ! !
73 * ! ! +---------+ ! !
74 * ! was -EPIPE -->--------------->! CLR2STS ! ! !
75 * ! ! +---------+ ! !
76 * ! ! ! ! !
77 * ! ! was error -->---- ! --------->\
78 * ! was error -->--------------------- ! ------------- ! --------->\
79 * ! ! ! ! !
80 * ! V ! ! !
81 * \--->+--------+ ! ! !
82 * ! STAT !<--------------------------/ ! !
83 * /--->+--------+ ! !
84 * ! ! ! !
85 * [C] was -EPIPE -->-----------\ ! !
86 * ! ! ! ! !
87 * +<---- len == 0 ! ! !
88 * ! ! ! ! !
89 * ! was error -->--------------------------------------!---------->\
90 * ! ! ! ! !
91 * +<---- bad CSW ! ! !
92 * +<---- bad tag ! ! !
93 * ! ! V ! !
94 * ! ! +--------+ ! !
95 * ! ! ! CLRRS ! ! !
96 * ! ! +--------+ ! !
97 * ! ! ! ! !
98 * \------- ! --------------------[C]--------\ ! !
99 * ! ! ! !
100 * cmd->error---\ +--------+ ! !
101 * ! +--------------->! SENSE !<----------/ !
102 * STAT_FAIL----/ +--------+ !
103 * ! ! V
104 * ! V +--------+
105 * \--------------------------------\--------------------->! DONE !
106 * +--------+
107 */
108
109 /*
110 * Definitions which have to be scattered once we understand the layout better.
111 */
112
113 /* Transport (despite PR in the name) */
114 #define US_PR_BULK 0x50 /* bulk only */
115
116 /* Protocol */
117 #define US_SC_SCSI 0x06 /* Transparent */
118
119 /*
120 * This many LUNs per USB device.
121 * Every one of them takes a host, see UB_MAX_HOSTS.
122 */
123 #define UB_MAX_LUNS 9
124
125 /*
126 */
127
128 #define UB_MINORS_PER_MAJOR 8
129
130 #define UB_MAX_CDB_SIZE 16 /* Corresponds to Bulk */
131
132 #define UB_SENSE_SIZE 18
133
134 /*
135 */
136
137 /* command block wrapper */
138 struct bulk_cb_wrap {
139 __le32 Signature; /* contains 'USBC' */
140 u32 Tag; /* unique per command id */
141 __le32 DataTransferLength; /* size of data */
142 u8 Flags; /* direction in bit 0 */
143 u8 Lun; /* LUN */
144 u8 Length; /* of of the CDB */
145 u8 CDB[UB_MAX_CDB_SIZE]; /* max command */
146 };
147
148 #define US_BULK_CB_WRAP_LEN 31
149 #define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */
150 #define US_BULK_FLAG_IN 1
151 #define US_BULK_FLAG_OUT 0
152
153 /* command status wrapper */
154 struct bulk_cs_wrap {
155 __le32 Signature; /* should = 'USBS' */
156 u32 Tag; /* same as original command */
157 __le32 Residue; /* amount not transferred */
158 u8 Status; /* see below */
159 };
160
161 #define US_BULK_CS_WRAP_LEN 13
162 #define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
163 #define US_BULK_STAT_OK 0
164 #define US_BULK_STAT_FAIL 1
165 #define US_BULK_STAT_PHASE 2
166
167 /* bulk-only class specific requests */
168 #define US_BULK_RESET_REQUEST 0xff
169 #define US_BULK_GET_MAX_LUN 0xfe
170
171 /*
172 */
173 struct ub_dev;
174
175 #define UB_MAX_REQ_SG 4
176 #define UB_MAX_SECTORS 64
177
178 /*
179 * A second is more than enough for a 32K transfer (UB_MAX_SECTORS)
180 * even if a webcam hogs the bus, but some devices need time to spin up.
181 */
182 #define UB_URB_TIMEOUT (HZ*2)
183 #define UB_DATA_TIMEOUT (HZ*5) /* ZIP does spin-ups in the data phase */
184 #define UB_STAT_TIMEOUT (HZ*5) /* Same spinups and eject for a dataless cmd. */
185 #define UB_CTRL_TIMEOUT (HZ/2) /* 500ms ought to be enough to clear a stall */
186
187 /*
188 * An instance of a SCSI command in transit.
189 */
190 #define UB_DIR_NONE 0
191 #define UB_DIR_READ 1
192 #define UB_DIR_ILLEGAL2 2
193 #define UB_DIR_WRITE 3
194
195 #define UB_DIR_CHAR(c) (((c)==UB_DIR_WRITE)? 'w': \
196 (((c)==UB_DIR_READ)? 'r': 'n'))
197
198 enum ub_scsi_cmd_state {
199 UB_CMDST_INIT, /* Initial state */
200 UB_CMDST_CMD, /* Command submitted */
201 UB_CMDST_DATA, /* Data phase */
202 UB_CMDST_CLR2STS, /* Clearing before requesting status */
203 UB_CMDST_STAT, /* Status phase */
204 UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */
205 UB_CMDST_CLRRS, /* Clearing before retrying status */
206 UB_CMDST_SENSE, /* Sending Request Sense */
207 UB_CMDST_DONE /* Final state */
208 };
209
210 static char *ub_scsi_cmd_stname[] = {
211 ". ",
212 "Cmd",
213 "dat",
214 "c2s",
215 "sts",
216 "clr",
217 "crs",
218 "Sen",
219 "fin"
220 };
221
222 struct ub_scsi_cmd {
223 unsigned char cdb[UB_MAX_CDB_SIZE];
224 unsigned char cdb_len;
225
226 unsigned char dir; /* 0 - none, 1 - read, 3 - write. */
227 unsigned char trace_index;
228 enum ub_scsi_cmd_state state;
229 unsigned int tag;
230 struct ub_scsi_cmd *next;
231
232 int error; /* Return code - valid upon done */
233 unsigned int act_len; /* Return size */
234 unsigned char key, asc, ascq; /* May be valid if error==-EIO */
235
236 int stat_count; /* Retries getting status. */
237
238 /*
239 * We do not support transfers from highmem pages
240 * because the underlying USB framework does not do what we need.
241 */
242 char *data; /* Requested buffer */
243 unsigned int len; /* Requested length */
244
245 struct ub_lun *lun;
246 void (*done)(struct ub_dev *, struct ub_scsi_cmd *);
247 void *back;
248 };
249
250 struct ub_request {
251 struct request *rq;
252 unsigned char dir;
253 unsigned int current_block;
254 unsigned int current_sg;
255 unsigned int nsg; /* sgv[nsg] */
256 struct scatterlist sgv[UB_MAX_REQ_SG];
257 };
258
259 /*
260 */
261 struct ub_capacity {
262 unsigned long nsec; /* Linux size - 512 byte sectors */
263 unsigned int bsize; /* Linux hardsect_size */
264 unsigned int bshift; /* Shift between 512 and hard sects */
265 };
266
267 /*
268 * The SCSI command tracing structure.
269 */
270
271 #define SCMD_ST_HIST_SZ 8
272 #define SCMD_TRACE_SZ 63 /* Less than 4KB of 61-byte lines */
273
274 struct ub_scsi_cmd_trace {
275 int hcur;
276 unsigned int tag;
277 unsigned int req_size, act_size;
278 unsigned char op;
279 unsigned char dir;
280 unsigned char key, asc, ascq;
281 char st_hst[SCMD_ST_HIST_SZ];
282 };
283
284 struct ub_scsi_trace {
285 int cur;
286 struct ub_scsi_cmd_trace vec[SCMD_TRACE_SZ];
287 };
288
289 /*
290 * This is a direct take-off from linux/include/completion.h
291 * The difference is that I do not wait on this thing, just poll.
292 * When I want to wait (ub_probe), I just use the stock completion.
293 *
294 * Note that INIT_COMPLETION takes no lock. It is correct. But why
295 * in the bloody hell that thing takes struct instead of pointer to struct
296 * is quite beyond me. I just copied it from the stock completion.
297 */
298 struct ub_completion {
299 unsigned int done;
300 spinlock_t lock;
301 };
302
303 static inline void ub_init_completion(struct ub_completion *x)
304 {
305 x->done = 0;
306 spin_lock_init(&x->lock);
307 }
308
309 #define UB_INIT_COMPLETION(x) ((x).done = 0)
310
311 static void ub_complete(struct ub_completion *x)
312 {
313 unsigned long flags;
314
315 spin_lock_irqsave(&x->lock, flags);
316 x->done++;
317 spin_unlock_irqrestore(&x->lock, flags);
318 }
319
320 static int ub_is_completed(struct ub_completion *x)
321 {
322 unsigned long flags;
323 int ret;
324
325 spin_lock_irqsave(&x->lock, flags);
326 ret = x->done;
327 spin_unlock_irqrestore(&x->lock, flags);
328 return ret;
329 }
330
331 /*
332 */
333 struct ub_scsi_cmd_queue {
334 int qlen, qmax;
335 struct ub_scsi_cmd *head, *tail;
336 };
337
338 /*
339 * The block device instance (one per LUN).
340 */
341 struct ub_lun {
342 struct ub_dev *udev;
343 struct list_head link;
344 struct gendisk *disk;
345 int id; /* Host index */
346 int num; /* LUN number */
347 char name[16];
348
349 int changed; /* Media was changed */
350 int removable;
351 int readonly;
352 int first_open; /* Kludge. See ub_bd_open. */
353
354 struct ub_request urq;
355
356 /* Use Ingo's mempool if or when we have more than one command. */
357 /*
358 * Currently we never need more than one command for the whole device.
359 * However, giving every LUN a command is a cheap and automatic way
360 * to enforce fairness between them.
361 */
362 int cmda[1];
363 struct ub_scsi_cmd cmdv[1];
364
365 struct ub_capacity capacity;
366 };
367
368 /*
369 * The USB device instance.
370 */
371 struct ub_dev {
372 spinlock_t lock;
373 atomic_t poison; /* The USB device is disconnected */
374 int openc; /* protected by ub_lock! */
375 /* kref is too implicit for our taste */
376 unsigned int tagcnt;
377 char name[12];
378 struct usb_device *dev;
379 struct usb_interface *intf;
380
381 struct list_head luns;
382
383 unsigned int send_bulk_pipe; /* cached pipe values */
384 unsigned int recv_bulk_pipe;
385 unsigned int send_ctrl_pipe;
386 unsigned int recv_ctrl_pipe;
387
388 struct tasklet_struct tasklet;
389
390 struct ub_scsi_cmd_queue cmd_queue;
391 struct ub_scsi_cmd top_rqs_cmd; /* REQUEST SENSE */
392 unsigned char top_sense[UB_SENSE_SIZE];
393
394 struct ub_completion work_done;
395 struct urb work_urb;
396 struct timer_list work_timer;
397 int last_pipe; /* What might need clearing */
398 __le32 signature; /* Learned signature */
399 struct bulk_cb_wrap work_bcb;
400 struct bulk_cs_wrap work_bcs;
401 struct usb_ctrlrequest work_cr;
402
403 int sg_stat[UB_MAX_REQ_SG+1];
404 struct ub_scsi_trace tr;
405 };
406
407 /*
408 */
409 static void ub_cleanup(struct ub_dev *sc);
410 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq);
411 static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
412 struct ub_scsi_cmd *cmd, struct request *rq);
413 static void ub_scsi_build_block(struct ub_lun *lun,
414 struct ub_scsi_cmd *cmd, struct ub_request *urq);
415 static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
416 struct ub_scsi_cmd *cmd, struct request *rq);
417 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
418 static void ub_end_rq(struct request *rq, int uptodate);
419 static int ub_request_advance(struct ub_dev *sc, struct ub_lun *lun,
420 struct ub_request *urq, struct ub_scsi_cmd *cmd);
421 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
422 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt);
423 static void ub_scsi_action(unsigned long _dev);
424 static void ub_scsi_dispatch(struct ub_dev *sc);
425 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
426 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc);
427 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
428 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
429 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
430 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
431 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
432 int stalled_pipe);
433 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd);
434 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun);
435 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
436 struct ub_capacity *ret);
437 static int ub_probe_lun(struct ub_dev *sc, int lnum);
438
439 /*
440 */
441 static struct usb_device_id ub_usb_ids[] = {
442 // { USB_DEVICE_VER(0x0781, 0x0002, 0x0009, 0x0009) }, /* SDDR-31 */
443 { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, US_SC_SCSI, US_PR_BULK) },
444 { }
445 };
446
447 MODULE_DEVICE_TABLE(usb, ub_usb_ids);
448
449 /*
450 * Find me a way to identify "next free minor" for add_disk(),
451 * and the array disappears the next day. However, the number of
452 * hosts has something to do with the naming and /proc/partitions.
453 * This has to be thought out in detail before changing.
454 * If UB_MAX_HOST was 1000, we'd use a bitmap. Or a better data structure.
455 */
456 #define UB_MAX_HOSTS 26
457 static char ub_hostv[UB_MAX_HOSTS];
458
459 static DEFINE_SPINLOCK(ub_lock); /* Locks globals and ->openc */
460
461 /*
462 * The SCSI command tracing procedures.
463 */
464
465 static void ub_cmdtr_new(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
466 {
467 int n;
468 struct ub_scsi_cmd_trace *t;
469
470 if ((n = sc->tr.cur + 1) == SCMD_TRACE_SZ) n = 0;
471 t = &sc->tr.vec[n];
472
473 memset(t, 0, sizeof(struct ub_scsi_cmd_trace));
474 t->tag = cmd->tag;
475 t->op = cmd->cdb[0];
476 t->dir = cmd->dir;
477 t->req_size = cmd->len;
478 t->st_hst[0] = cmd->state;
479
480 sc->tr.cur = n;
481 cmd->trace_index = n;
482 }
483
484 static void ub_cmdtr_state(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
485 {
486 int n;
487 struct ub_scsi_cmd_trace *t;
488
489 t = &sc->tr.vec[cmd->trace_index];
490 if (t->tag == cmd->tag) {
491 if ((n = t->hcur + 1) == SCMD_ST_HIST_SZ) n = 0;
492 t->st_hst[n] = cmd->state;
493 t->hcur = n;
494 }
495 }
496
497 static void ub_cmdtr_act_len(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
498 {
499 struct ub_scsi_cmd_trace *t;
500
501 t = &sc->tr.vec[cmd->trace_index];
502 if (t->tag == cmd->tag)
503 t->act_size = cmd->act_len;
504 }
505
506 static void ub_cmdtr_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
507 unsigned char *sense)
508 {
509 struct ub_scsi_cmd_trace *t;
510
511 t = &sc->tr.vec[cmd->trace_index];
512 if (t->tag == cmd->tag) {
513 t->key = sense[2] & 0x0F;
514 t->asc = sense[12];
515 t->ascq = sense[13];
516 }
517 }
518
519 static ssize_t ub_diag_show(struct device *dev, struct device_attribute *attr,
520 char *page)
521 {
522 struct usb_interface *intf;
523 struct ub_dev *sc;
524 struct list_head *p;
525 struct ub_lun *lun;
526 int cnt;
527 unsigned long flags;
528 int nc, nh;
529 int i, j;
530 struct ub_scsi_cmd_trace *t;
531
532 intf = to_usb_interface(dev);
533 sc = usb_get_intfdata(intf);
534 if (sc == NULL)
535 return 0;
536
537 cnt = 0;
538 spin_lock_irqsave(&sc->lock, flags);
539
540 cnt += sprintf(page + cnt,
541 "qlen %d qmax %d\n",
542 sc->cmd_queue.qlen, sc->cmd_queue.qmax);
543 cnt += sprintf(page + cnt,
544 "sg %d %d %d %d %d\n",
545 sc->sg_stat[0],
546 sc->sg_stat[1],
547 sc->sg_stat[2],
548 sc->sg_stat[3],
549 sc->sg_stat[4]);
550
551 list_for_each (p, &sc->luns) {
552 lun = list_entry(p, struct ub_lun, link);
553 cnt += sprintf(page + cnt,
554 "lun %u changed %d removable %d readonly %d\n",
555 lun->num, lun->changed, lun->removable, lun->readonly);
556 }
557
558 if ((nc = sc->tr.cur + 1) == SCMD_TRACE_SZ) nc = 0;
559 for (j = 0; j < SCMD_TRACE_SZ; j++) {
560 t = &sc->tr.vec[nc];
561
562 cnt += sprintf(page + cnt, "%08x %02x", t->tag, t->op);
563 if (t->op == REQUEST_SENSE) {
564 cnt += sprintf(page + cnt, " [sense %x %02x %02x]",
565 t->key, t->asc, t->ascq);
566 } else {
567 cnt += sprintf(page + cnt, " %c", UB_DIR_CHAR(t->dir));
568 cnt += sprintf(page + cnt, " [%5d %5d]",
569 t->req_size, t->act_size);
570 }
571 if ((nh = t->hcur + 1) == SCMD_ST_HIST_SZ) nh = 0;
572 for (i = 0; i < SCMD_ST_HIST_SZ; i++) {
573 cnt += sprintf(page + cnt, " %s",
574 ub_scsi_cmd_stname[(int)t->st_hst[nh]]);
575 if (++nh == SCMD_ST_HIST_SZ) nh = 0;
576 }
577 cnt += sprintf(page + cnt, "\n");
578
579 if (++nc == SCMD_TRACE_SZ) nc = 0;
580 }
581
582 spin_unlock_irqrestore(&sc->lock, flags);
583 return cnt;
584 }
585
586 static DEVICE_ATTR(diag, S_IRUGO, ub_diag_show, NULL); /* N.B. World readable */
587
588 /*
589 * The id allocator.
590 *
591 * This also stores the host for indexing by minor, which is somewhat dirty.
592 */
593 static int ub_id_get(void)
594 {
595 unsigned long flags;
596 int i;
597
598 spin_lock_irqsave(&ub_lock, flags);
599 for (i = 0; i < UB_MAX_HOSTS; i++) {
600 if (ub_hostv[i] == 0) {
601 ub_hostv[i] = 1;
602 spin_unlock_irqrestore(&ub_lock, flags);
603 return i;
604 }
605 }
606 spin_unlock_irqrestore(&ub_lock, flags);
607 return -1;
608 }
609
610 static void ub_id_put(int id)
611 {
612 unsigned long flags;
613
614 if (id < 0 || id >= UB_MAX_HOSTS) {
615 printk(KERN_ERR DRV_NAME ": bad host ID %d\n", id);
616 return;
617 }
618
619 spin_lock_irqsave(&ub_lock, flags);
620 if (ub_hostv[id] == 0) {
621 spin_unlock_irqrestore(&ub_lock, flags);
622 printk(KERN_ERR DRV_NAME ": freeing free host ID %d\n", id);
623 return;
624 }
625 ub_hostv[id] = 0;
626 spin_unlock_irqrestore(&ub_lock, flags);
627 }
628
629 /*
630 * Downcount for deallocation. This rides on two assumptions:
631 * - once something is poisoned, its refcount cannot grow
632 * - opens cannot happen at this time (del_gendisk was done)
633 * If the above is true, we can drop the lock, which we need for
634 * blk_cleanup_queue(): the silly thing may attempt to sleep.
635 * [Actually, it never needs to sleep for us, but it calls might_sleep()]
636 */
637 static void ub_put(struct ub_dev *sc)
638 {
639 unsigned long flags;
640
641 spin_lock_irqsave(&ub_lock, flags);
642 --sc->openc;
643 if (sc->openc == 0 && atomic_read(&sc->poison)) {
644 spin_unlock_irqrestore(&ub_lock, flags);
645 ub_cleanup(sc);
646 } else {
647 spin_unlock_irqrestore(&ub_lock, flags);
648 }
649 }
650
651 /*
652 * Final cleanup and deallocation.
653 */
654 static void ub_cleanup(struct ub_dev *sc)
655 {
656 struct list_head *p;
657 struct ub_lun *lun;
658 request_queue_t *q;
659
660 while (!list_empty(&sc->luns)) {
661 p = sc->luns.next;
662 lun = list_entry(p, struct ub_lun, link);
663 list_del(p);
664
665 /* I don't think queue can be NULL. But... Stolen from sx8.c */
666 if ((q = lun->disk->queue) != NULL)
667 blk_cleanup_queue(q);
668 /*
669 * If we zero disk->private_data BEFORE put_disk, we have
670 * to check for NULL all over the place in open, release,
671 * check_media and revalidate, because the block level
672 * semaphore is well inside the put_disk.
673 * But we cannot zero after the call, because *disk is gone.
674 * The sd.c is blatantly racy in this area.
675 */
676 /* disk->private_data = NULL; */
677 put_disk(lun->disk);
678 lun->disk = NULL;
679
680 ub_id_put(lun->id);
681 kfree(lun);
682 }
683
684 kfree(sc);
685 }
686
687 /*
688 * The "command allocator".
689 */
690 static struct ub_scsi_cmd *ub_get_cmd(struct ub_lun *lun)
691 {
692 struct ub_scsi_cmd *ret;
693
694 if (lun->cmda[0])
695 return NULL;
696 ret = &lun->cmdv[0];
697 lun->cmda[0] = 1;
698 return ret;
699 }
700
701 static void ub_put_cmd(struct ub_lun *lun, struct ub_scsi_cmd *cmd)
702 {
703 if (cmd != &lun->cmdv[0]) {
704 printk(KERN_WARNING "%s: releasing a foreign cmd %p\n",
705 lun->name, cmd);
706 return;
707 }
708 if (!lun->cmda[0]) {
709 printk(KERN_WARNING "%s: releasing a free cmd\n", lun->name);
710 return;
711 }
712 lun->cmda[0] = 0;
713 }
714
715 /*
716 * The command queue.
717 */
718 static void ub_cmdq_add(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
719 {
720 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
721
722 if (t->qlen++ == 0) {
723 t->head = cmd;
724 t->tail = cmd;
725 } else {
726 t->tail->next = cmd;
727 t->tail = cmd;
728 }
729
730 if (t->qlen > t->qmax)
731 t->qmax = t->qlen;
732 }
733
734 static void ub_cmdq_insert(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
735 {
736 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
737
738 if (t->qlen++ == 0) {
739 t->head = cmd;
740 t->tail = cmd;
741 } else {
742 cmd->next = t->head;
743 t->head = cmd;
744 }
745
746 if (t->qlen > t->qmax)
747 t->qmax = t->qlen;
748 }
749
750 static struct ub_scsi_cmd *ub_cmdq_pop(struct ub_dev *sc)
751 {
752 struct ub_scsi_cmd_queue *t = &sc->cmd_queue;
753 struct ub_scsi_cmd *cmd;
754
755 if (t->qlen == 0)
756 return NULL;
757 if (--t->qlen == 0)
758 t->tail = NULL;
759 cmd = t->head;
760 t->head = cmd->next;
761 cmd->next = NULL;
762 return cmd;
763 }
764
765 #define ub_cmdq_peek(sc) ((sc)->cmd_queue.head)
766
767 /*
768 * The request function is our main entry point
769 */
770
771 static void ub_request_fn(request_queue_t *q)
772 {
773 struct ub_lun *lun = q->queuedata;
774 struct request *rq;
775
776 while ((rq = elv_next_request(q)) != NULL) {
777 if (ub_request_fn_1(lun, rq) != 0) {
778 blk_stop_queue(q);
779 break;
780 }
781 }
782 }
783
784 static int ub_request_fn_1(struct ub_lun *lun, struct request *rq)
785 {
786 struct ub_dev *sc = lun->udev;
787 struct ub_scsi_cmd *cmd;
788 int rc;
789
790 if (atomic_read(&sc->poison) || lun->changed) {
791 blkdev_dequeue_request(rq);
792 ub_end_rq(rq, 0);
793 return 0;
794 }
795
796 if (lun->urq.rq != NULL)
797 return -1;
798 if ((cmd = ub_get_cmd(lun)) == NULL)
799 return -1;
800 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
801
802 blkdev_dequeue_request(rq);
803 if (blk_pc_request(rq)) {
804 rc = ub_cmd_build_packet(sc, lun, cmd, rq);
805 } else {
806 rc = ub_cmd_build_block(sc, lun, cmd, rq);
807 }
808 if (rc != 0) {
809 ub_put_cmd(lun, cmd);
810 ub_end_rq(rq, 0);
811 return 0;
812 }
813 cmd->state = UB_CMDST_INIT;
814 cmd->lun = lun;
815 cmd->done = ub_rw_cmd_done;
816 cmd->back = &lun->urq;
817
818 cmd->tag = sc->tagcnt++;
819 if (ub_submit_scsi(sc, cmd) != 0) {
820 ub_put_cmd(lun, cmd);
821 ub_end_rq(rq, 0);
822 return 0;
823 }
824
825 return 0;
826 }
827
828 static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
829 struct ub_scsi_cmd *cmd, struct request *rq)
830 {
831 struct ub_request *urq;
832 int ub_dir;
833 int n_elem;
834
835 urq = &lun->urq;
836 memset(urq, 0, sizeof(struct ub_request));
837
838 if (rq_data_dir(rq) == WRITE)
839 ub_dir = UB_DIR_WRITE;
840 else
841 ub_dir = UB_DIR_READ;
842
843 /*
844 * get scatterlist from block layer
845 */
846 n_elem = blk_rq_map_sg(lun->disk->queue, rq, &urq->sgv[0]);
847 if (n_elem <= 0) {
848 printk(KERN_INFO "%s: failed request map (%d)\n",
849 sc->name, n_elem); /* P3 */
850 return -1; /* request with no s/g entries? */
851 }
852 if (n_elem > UB_MAX_REQ_SG) { /* Paranoia */
853 printk(KERN_WARNING "%s: request with %d segments\n",
854 sc->name, n_elem);
855 return -1;
856 }
857 urq->nsg = n_elem;
858 sc->sg_stat[n_elem]++;
859
860 /*
861 * build the command
862 *
863 * The call to blk_queue_hardsect_size() guarantees that request
864 * is aligned, but it is given in terms of 512 byte units, always.
865 */
866 urq->current_block = rq->sector >> lun->capacity.bshift;
867 // nblks = rq->nr_sectors >> lun->capacity.bshift;
868
869 urq->rq = rq;
870 urq->current_sg = 0;
871 urq->dir = ub_dir;
872
873 ub_scsi_build_block(lun, cmd, urq);
874 return 0;
875 }
876
877 static void ub_scsi_build_block(struct ub_lun *lun,
878 struct ub_scsi_cmd *cmd, struct ub_request *urq)
879 {
880 struct scatterlist *sg;
881 unsigned int block, nblks;
882
883 sg = &urq->sgv[urq->current_sg];
884
885 block = urq->current_block;
886 nblks = sg->length >> (lun->capacity.bshift + 9);
887
888 cmd->cdb[0] = (urq->dir == UB_DIR_READ)? READ_10: WRITE_10;
889 /* 10-byte uses 4 bytes of LBA: 2147483648KB, 2097152MB, 2048GB */
890 cmd->cdb[2] = block >> 24;
891 cmd->cdb[3] = block >> 16;
892 cmd->cdb[4] = block >> 8;
893 cmd->cdb[5] = block;
894 cmd->cdb[7] = nblks >> 8;
895 cmd->cdb[8] = nblks;
896 cmd->cdb_len = 10;
897
898 cmd->dir = urq->dir;
899 cmd->data = page_address(sg->page) + sg->offset;
900 cmd->len = sg->length;
901 }
902
903 static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
904 struct ub_scsi_cmd *cmd, struct request *rq)
905 {
906 struct ub_request *urq;
907
908 urq = &lun->urq;
909 memset(urq, 0, sizeof(struct ub_request));
910 urq->rq = rq;
911 sc->sg_stat[0]++;
912
913 if (rq->data_len != 0 && rq->data == NULL) {
914 static int do_print = 1;
915 if (do_print) {
916 printk(KERN_WARNING "%s: unmapped packet request"
917 " flags 0x%lx length %d\n",
918 sc->name, rq->flags, rq->data_len);
919 do_print = 0;
920 }
921 return -1;
922 }
923
924 memcpy(&cmd->cdb, rq->cmd, rq->cmd_len);
925 cmd->cdb_len = rq->cmd_len;
926
927 if (rq->data_len == 0) {
928 cmd->dir = UB_DIR_NONE;
929 } else {
930 if (rq_data_dir(rq) == WRITE)
931 cmd->dir = UB_DIR_WRITE;
932 else
933 cmd->dir = UB_DIR_READ;
934 }
935 cmd->data = rq->data;
936 cmd->len = rq->data_len;
937
938 return 0;
939 }
940
941 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
942 {
943 struct ub_lun *lun = cmd->lun;
944 struct ub_request *urq = cmd->back;
945 struct request *rq;
946 int uptodate;
947
948 rq = urq->rq;
949
950 if (blk_pc_request(rq)) {
951 /* UB_SENSE_SIZE is smaller than SCSI_SENSE_BUFFERSIZE */
952 memcpy(rq->sense, sc->top_sense, UB_SENSE_SIZE);
953 rq->sense_len = UB_SENSE_SIZE;
954 }
955
956 if (cmd->error == 0)
957 uptodate = 1;
958 else
959 uptodate = 0;
960
961 if (cmd->error == 0 && urq->current_sg+1 < urq->nsg) {
962 if (ub_request_advance(sc, lun, urq, cmd) == 0) {
963 /* Stay on target... */
964 return;
965 }
966 uptodate = 0;
967 }
968
969 urq->rq = NULL;
970
971 ub_put_cmd(lun, cmd);
972 ub_end_rq(rq, uptodate);
973 blk_start_queue(lun->disk->queue);
974 }
975
976 static void ub_end_rq(struct request *rq, int uptodate)
977 {
978 int rc;
979
980 rc = end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
981 // assert(rc == 0);
982 end_that_request_last(rq);
983 }
984
985 static int ub_request_advance(struct ub_dev *sc, struct ub_lun *lun,
986 struct ub_request *urq, struct ub_scsi_cmd *cmd)
987 {
988 struct scatterlist *sg;
989 unsigned int nblks;
990
991 /* XXX This is temporary, until we sort out S/G in packet requests. */
992 if (blk_pc_request(urq->rq)) {
993 printk(KERN_WARNING
994 "2-segment packet request completed\n"); /* P3 */
995 return -1;
996 }
997
998 sg = &urq->sgv[urq->current_sg];
999 nblks = sg->length >> (lun->capacity.bshift + 9);
1000 urq->current_block += nblks;
1001 urq->current_sg++;
1002 sg++;
1003
1004 memset(cmd, 0, sizeof(struct ub_scsi_cmd));
1005 ub_scsi_build_block(lun, cmd, urq);
1006 cmd->state = UB_CMDST_INIT;
1007 cmd->lun = lun;
1008 cmd->done = ub_rw_cmd_done;
1009 cmd->back = &lun->urq;
1010
1011 cmd->tag = sc->tagcnt++;
1012 if (ub_submit_scsi(sc, cmd) != 0) {
1013 return -1;
1014 }
1015
1016 return 0;
1017 }
1018
1019 /*
1020 * Submit a regular SCSI operation (not an auto-sense).
1021 *
1022 * The Iron Law of Good Submit Routine is:
1023 * Zero return - callback is done, Nonzero return - callback is not done.
1024 * No exceptions.
1025 *
1026 * Host is assumed locked.
1027 *
1028 * XXX We only support Bulk for the moment.
1029 */
1030 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1031 {
1032
1033 if (cmd->state != UB_CMDST_INIT ||
1034 (cmd->dir != UB_DIR_NONE && cmd->len == 0)) {
1035 return -EINVAL;
1036 }
1037
1038 ub_cmdq_add(sc, cmd);
1039 /*
1040 * We can call ub_scsi_dispatch(sc) right away here, but it's a little
1041 * safer to jump to a tasklet, in case upper layers do something silly.
1042 */
1043 tasklet_schedule(&sc->tasklet);
1044 return 0;
1045 }
1046
1047 /*
1048 * Submit the first URB for the queued command.
1049 * This function does not deal with queueing in any way.
1050 */
1051 static int ub_scsi_cmd_start(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1052 {
1053 struct bulk_cb_wrap *bcb;
1054 int rc;
1055
1056 bcb = &sc->work_bcb;
1057
1058 /*
1059 * ``If the allocation length is eighteen or greater, and a device
1060 * server returns less than eithteen bytes of data, the application
1061 * client should assume that the bytes not transferred would have been
1062 * zeroes had the device server returned those bytes.''
1063 *
1064 * We zero sense for all commands so that when a packet request
1065 * fails it does not return a stale sense.
1066 */
1067 memset(&sc->top_sense, 0, UB_SENSE_SIZE);
1068
1069 /* set up the command wrapper */
1070 bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
1071 bcb->Tag = cmd->tag; /* Endianness is not important */
1072 bcb->DataTransferLength = cpu_to_le32(cmd->len);
1073 bcb->Flags = (cmd->dir == UB_DIR_READ) ? 0x80 : 0;
1074 bcb->Lun = (cmd->lun != NULL) ? cmd->lun->num : 0;
1075 bcb->Length = cmd->cdb_len;
1076
1077 /* copy the command payload */
1078 memcpy(bcb->CDB, cmd->cdb, UB_MAX_CDB_SIZE);
1079
1080 UB_INIT_COMPLETION(sc->work_done);
1081
1082 sc->last_pipe = sc->send_bulk_pipe;
1083 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->send_bulk_pipe,
1084 bcb, US_BULK_CB_WRAP_LEN, ub_urb_complete, sc);
1085 sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
1086
1087 /* Fill what we shouldn't be filling, because usb-storage did so. */
1088 sc->work_urb.actual_length = 0;
1089 sc->work_urb.error_count = 0;
1090 sc->work_urb.status = 0;
1091
1092 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1093 /* XXX Clear stalls */
1094 printk("ub: cmd #%d start failed (%d)\n", cmd->tag, rc); /* P3 */
1095 ub_complete(&sc->work_done);
1096 return rc;
1097 }
1098
1099 sc->work_timer.expires = jiffies + UB_URB_TIMEOUT;
1100 add_timer(&sc->work_timer);
1101
1102 cmd->state = UB_CMDST_CMD;
1103 ub_cmdtr_state(sc, cmd);
1104 return 0;
1105 }
1106
1107 /*
1108 * Timeout handler.
1109 */
1110 static void ub_urb_timeout(unsigned long arg)
1111 {
1112 struct ub_dev *sc = (struct ub_dev *) arg;
1113 unsigned long flags;
1114
1115 spin_lock_irqsave(&sc->lock, flags);
1116 usb_unlink_urb(&sc->work_urb);
1117 spin_unlock_irqrestore(&sc->lock, flags);
1118 }
1119
1120 /*
1121 * Completion routine for the work URB.
1122 *
1123 * This can be called directly from usb_submit_urb (while we have
1124 * the sc->lock taken) and from an interrupt (while we do NOT have
1125 * the sc->lock taken). Therefore, bounce this off to a tasklet.
1126 */
1127 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt)
1128 {
1129 struct ub_dev *sc = urb->context;
1130
1131 ub_complete(&sc->work_done);
1132 tasklet_schedule(&sc->tasklet);
1133 }
1134
1135 static void ub_scsi_action(unsigned long _dev)
1136 {
1137 struct ub_dev *sc = (struct ub_dev *) _dev;
1138 unsigned long flags;
1139
1140 spin_lock_irqsave(&sc->lock, flags);
1141 del_timer(&sc->work_timer);
1142 ub_scsi_dispatch(sc);
1143 spin_unlock_irqrestore(&sc->lock, flags);
1144 }
1145
1146 static void ub_scsi_dispatch(struct ub_dev *sc)
1147 {
1148 struct ub_scsi_cmd *cmd;
1149 int rc;
1150
1151 while ((cmd = ub_cmdq_peek(sc)) != NULL) {
1152 if (cmd->state == UB_CMDST_DONE) {
1153 ub_cmdq_pop(sc);
1154 (*cmd->done)(sc, cmd);
1155 } else if (cmd->state == UB_CMDST_INIT) {
1156 ub_cmdtr_new(sc, cmd);
1157 if ((rc = ub_scsi_cmd_start(sc, cmd)) == 0)
1158 break;
1159 cmd->error = rc;
1160 cmd->state = UB_CMDST_DONE;
1161 ub_cmdtr_state(sc, cmd);
1162 } else {
1163 if (!ub_is_completed(&sc->work_done))
1164 break;
1165 ub_scsi_urb_compl(sc, cmd);
1166 }
1167 }
1168 }
1169
1170 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1171 {
1172 struct urb *urb = &sc->work_urb;
1173 struct bulk_cs_wrap *bcs;
1174 int pipe;
1175 int rc;
1176
1177 if (atomic_read(&sc->poison)) {
1178 /* A little too simplistic, I feel... */
1179 goto Bad_End;
1180 }
1181
1182 if (cmd->state == UB_CMDST_CLEAR) {
1183 if (urb->status == -EPIPE) {
1184 /*
1185 * STALL while clearning STALL.
1186 * The control pipe clears itself - nothing to do.
1187 * XXX Might try to reset the device here and retry.
1188 */
1189 printk(KERN_NOTICE "%s: stall on control pipe\n",
1190 sc->name);
1191 goto Bad_End;
1192 }
1193
1194 /*
1195 * We ignore the result for the halt clear.
1196 */
1197
1198 /* reset the endpoint toggle */
1199 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1200 usb_pipeout(sc->last_pipe), 0);
1201
1202 ub_state_sense(sc, cmd);
1203
1204 } else if (cmd->state == UB_CMDST_CLR2STS) {
1205 if (urb->status == -EPIPE) {
1206 /*
1207 * STALL while clearning STALL.
1208 * The control pipe clears itself - nothing to do.
1209 * XXX Might try to reset the device here and retry.
1210 */
1211 printk(KERN_NOTICE "%s: stall on control pipe\n",
1212 sc->name);
1213 goto Bad_End;
1214 }
1215
1216 /*
1217 * We ignore the result for the halt clear.
1218 */
1219
1220 /* reset the endpoint toggle */
1221 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1222 usb_pipeout(sc->last_pipe), 0);
1223
1224 ub_state_stat(sc, cmd);
1225
1226 } else if (cmd->state == UB_CMDST_CLRRS) {
1227 if (urb->status == -EPIPE) {
1228 /*
1229 * STALL while clearning STALL.
1230 * The control pipe clears itself - nothing to do.
1231 * XXX Might try to reset the device here and retry.
1232 */
1233 printk(KERN_NOTICE "%s: stall on control pipe\n",
1234 sc->name);
1235 goto Bad_End;
1236 }
1237
1238 /*
1239 * We ignore the result for the halt clear.
1240 */
1241
1242 /* reset the endpoint toggle */
1243 usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
1244 usb_pipeout(sc->last_pipe), 0);
1245
1246 ub_state_stat_counted(sc, cmd);
1247
1248 } else if (cmd->state == UB_CMDST_CMD) {
1249 if (urb->status == -EPIPE) {
1250 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1251 if (rc != 0) {
1252 printk(KERN_NOTICE "%s: "
1253 "unable to submit clear (%d)\n",
1254 sc->name, rc);
1255 /*
1256 * This is typically ENOMEM or some other such shit.
1257 * Retrying is pointless. Just do Bad End on it...
1258 */
1259 goto Bad_End;
1260 }
1261 cmd->state = UB_CMDST_CLEAR;
1262 ub_cmdtr_state(sc, cmd);
1263 return;
1264 }
1265 if (urb->status != 0) {
1266 printk("ub: cmd #%d cmd status (%d)\n", cmd->tag, urb->status); /* P3 */
1267 goto Bad_End;
1268 }
1269 if (urb->actual_length != US_BULK_CB_WRAP_LEN) {
1270 printk("ub: cmd #%d xferred %d\n", cmd->tag, urb->actual_length); /* P3 */
1271 /* XXX Must do reset here to unconfuse the device */
1272 goto Bad_End;
1273 }
1274
1275 if (cmd->dir == UB_DIR_NONE) {
1276 ub_state_stat(sc, cmd);
1277 return;
1278 }
1279
1280 UB_INIT_COMPLETION(sc->work_done);
1281
1282 if (cmd->dir == UB_DIR_READ)
1283 pipe = sc->recv_bulk_pipe;
1284 else
1285 pipe = sc->send_bulk_pipe;
1286 sc->last_pipe = pipe;
1287 usb_fill_bulk_urb(&sc->work_urb, sc->dev, pipe,
1288 cmd->data, cmd->len, ub_urb_complete, sc);
1289 sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
1290 sc->work_urb.actual_length = 0;
1291 sc->work_urb.error_count = 0;
1292 sc->work_urb.status = 0;
1293
1294 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1295 /* XXX Clear stalls */
1296 printk("ub: data #%d submit failed (%d)\n", cmd->tag, rc); /* P3 */
1297 ub_complete(&sc->work_done);
1298 ub_state_done(sc, cmd, rc);
1299 return;
1300 }
1301
1302 sc->work_timer.expires = jiffies + UB_DATA_TIMEOUT;
1303 add_timer(&sc->work_timer);
1304
1305 cmd->state = UB_CMDST_DATA;
1306 ub_cmdtr_state(sc, cmd);
1307
1308 } else if (cmd->state == UB_CMDST_DATA) {
1309 if (urb->status == -EPIPE) {
1310 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1311 if (rc != 0) {
1312 printk(KERN_NOTICE "%s: "
1313 "unable to submit clear (%d)\n",
1314 sc->name, rc);
1315 /*
1316 * This is typically ENOMEM or some other such shit.
1317 * Retrying is pointless. Just do Bad End on it...
1318 */
1319 goto Bad_End;
1320 }
1321 cmd->state = UB_CMDST_CLR2STS;
1322 ub_cmdtr_state(sc, cmd);
1323 return;
1324 }
1325 if (urb->status == -EOVERFLOW) {
1326 /*
1327 * A babble? Failure, but we must transfer CSW now.
1328 */
1329 cmd->error = -EOVERFLOW; /* A cheap trick... */
1330 } else {
1331 if (urb->status != 0)
1332 goto Bad_End;
1333 }
1334
1335 cmd->act_len = urb->actual_length;
1336 ub_cmdtr_act_len(sc, cmd);
1337
1338 ub_state_stat(sc, cmd);
1339
1340 } else if (cmd->state == UB_CMDST_STAT) {
1341 if (urb->status == -EPIPE) {
1342 rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
1343 if (rc != 0) {
1344 printk(KERN_NOTICE "%s: "
1345 "unable to submit clear (%d)\n",
1346 sc->name, rc);
1347 /*
1348 * This is typically ENOMEM or some other such shit.
1349 * Retrying is pointless. Just do Bad End on it...
1350 */
1351 goto Bad_End;
1352 }
1353
1354 /*
1355 * Having a stall when getting CSW is an error, so
1356 * make sure uppper levels are not oblivious to it.
1357 */
1358 cmd->error = -EIO; /* A cheap trick... */
1359
1360 cmd->state = UB_CMDST_CLRRS;
1361 ub_cmdtr_state(sc, cmd);
1362 return;
1363 }
1364 if (urb->status == -EOVERFLOW) {
1365 /*
1366 * XXX We are screwed here. Retrying is pointless,
1367 * because the pipelined data will not get in until
1368 * we read with a big enough buffer. We must reset XXX.
1369 */
1370 goto Bad_End;
1371 }
1372 if (urb->status != 0)
1373 goto Bad_End;
1374
1375 if (urb->actual_length == 0) {
1376 ub_state_stat_counted(sc, cmd);
1377 return;
1378 }
1379
1380 /*
1381 * Check the returned Bulk protocol status.
1382 * The status block has to be validated first.
1383 */
1384
1385 bcs = &sc->work_bcs;
1386
1387 if (sc->signature == cpu_to_le32(0)) {
1388 /*
1389 * This is the first reply, so do not perform the check.
1390 * Instead, remember the signature the device uses
1391 * for future checks. But do not allow a nul.
1392 */
1393 sc->signature = bcs->Signature;
1394 if (sc->signature == cpu_to_le32(0)) {
1395 ub_state_stat_counted(sc, cmd);
1396 return;
1397 }
1398 } else {
1399 if (bcs->Signature != sc->signature) {
1400 ub_state_stat_counted(sc, cmd);
1401 return;
1402 }
1403 }
1404
1405 if (bcs->Tag != cmd->tag) {
1406 /*
1407 * This usually happens when we disagree with the
1408 * device's microcode about something. For instance,
1409 * a few of them throw this after timeouts. They buffer
1410 * commands and reply at commands we timed out before.
1411 * Without flushing these replies we loop forever.
1412 */
1413 ub_state_stat_counted(sc, cmd);
1414 return;
1415 }
1416
1417 rc = le32_to_cpu(bcs->Residue);
1418 if (rc != cmd->len - cmd->act_len) {
1419 /*
1420 * It is all right to transfer less, the caller has
1421 * to check. But it's not all right if the device
1422 * counts disagree with our counts.
1423 */
1424 /* P3 */ printk("%s: resid %d len %d act %d\n",
1425 sc->name, rc, cmd->len, cmd->act_len);
1426 goto Bad_End;
1427 }
1428
1429 switch (bcs->Status) {
1430 case US_BULK_STAT_OK:
1431 break;
1432 case US_BULK_STAT_FAIL:
1433 ub_state_sense(sc, cmd);
1434 return;
1435 case US_BULK_STAT_PHASE:
1436 /* XXX We must reset the transport here */
1437 /* P3 */ printk("%s: status PHASE\n", sc->name);
1438 goto Bad_End;
1439 default:
1440 printk(KERN_INFO "%s: unknown CSW status 0x%x\n",
1441 sc->name, bcs->Status);
1442 goto Bad_End;
1443 }
1444
1445 /* Not zeroing error to preserve a babble indicator */
1446 if (cmd->error != 0) {
1447 ub_state_sense(sc, cmd);
1448 return;
1449 }
1450 cmd->state = UB_CMDST_DONE;
1451 ub_cmdtr_state(sc, cmd);
1452 ub_cmdq_pop(sc);
1453 (*cmd->done)(sc, cmd);
1454
1455 } else if (cmd->state == UB_CMDST_SENSE) {
1456 ub_state_done(sc, cmd, -EIO);
1457
1458 } else {
1459 printk(KERN_WARNING "%s: "
1460 "wrong command state %d\n",
1461 sc->name, cmd->state);
1462 goto Bad_End;
1463 }
1464 return;
1465
1466 Bad_End: /* Little Excel is dead */
1467 ub_state_done(sc, cmd, -EIO);
1468 }
1469
1470 /*
1471 * Factorization helper for the command state machine:
1472 * Finish the command.
1473 */
1474 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc)
1475 {
1476
1477 cmd->error = rc;
1478 cmd->state = UB_CMDST_DONE;
1479 ub_cmdtr_state(sc, cmd);
1480 ub_cmdq_pop(sc);
1481 (*cmd->done)(sc, cmd);
1482 }
1483
1484 /*
1485 * Factorization helper for the command state machine:
1486 * Submit a CSW read.
1487 */
1488 static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1489 {
1490 int rc;
1491
1492 UB_INIT_COMPLETION(sc->work_done);
1493
1494 sc->last_pipe = sc->recv_bulk_pipe;
1495 usb_fill_bulk_urb(&sc->work_urb, sc->dev, sc->recv_bulk_pipe,
1496 &sc->work_bcs, US_BULK_CS_WRAP_LEN, ub_urb_complete, sc);
1497 sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
1498 sc->work_urb.actual_length = 0;
1499 sc->work_urb.error_count = 0;
1500 sc->work_urb.status = 0;
1501
1502 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1503 /* XXX Clear stalls */
1504 ub_complete(&sc->work_done);
1505 ub_state_done(sc, cmd, rc);
1506 return -1;
1507 }
1508
1509 sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
1510 add_timer(&sc->work_timer);
1511 return 0;
1512 }
1513
1514 /*
1515 * Factorization helper for the command state machine:
1516 * Submit a CSW read and go to STAT state.
1517 */
1518 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1519 {
1520
1521 if (__ub_state_stat(sc, cmd) != 0)
1522 return;
1523
1524 cmd->stat_count = 0;
1525 cmd->state = UB_CMDST_STAT;
1526 ub_cmdtr_state(sc, cmd);
1527 }
1528
1529 /*
1530 * Factorization helper for the command state machine:
1531 * Submit a CSW read and go to STAT state with counter (along [C] path).
1532 */
1533 static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1534 {
1535
1536 if (++cmd->stat_count >= 4) {
1537 ub_state_sense(sc, cmd);
1538 return;
1539 }
1540
1541 if (__ub_state_stat(sc, cmd) != 0)
1542 return;
1543
1544 cmd->state = UB_CMDST_STAT;
1545 ub_cmdtr_state(sc, cmd);
1546 }
1547
1548 /*
1549 * Factorization helper for the command state machine:
1550 * Submit a REQUEST SENSE and go to SENSE state.
1551 */
1552 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1553 {
1554 struct ub_scsi_cmd *scmd;
1555 int rc;
1556
1557 if (cmd->cdb[0] == REQUEST_SENSE) {
1558 rc = -EPIPE;
1559 goto error;
1560 }
1561
1562 scmd = &sc->top_rqs_cmd;
1563 scmd->cdb[0] = REQUEST_SENSE;
1564 scmd->cdb[4] = UB_SENSE_SIZE;
1565 scmd->cdb_len = 6;
1566 scmd->dir = UB_DIR_READ;
1567 scmd->state = UB_CMDST_INIT;
1568 scmd->data = sc->top_sense;
1569 scmd->len = UB_SENSE_SIZE;
1570 scmd->lun = cmd->lun;
1571 scmd->done = ub_top_sense_done;
1572 scmd->back = cmd;
1573
1574 scmd->tag = sc->tagcnt++;
1575
1576 cmd->state = UB_CMDST_SENSE;
1577 ub_cmdtr_state(sc, cmd);
1578
1579 ub_cmdq_insert(sc, scmd);
1580 return;
1581
1582 error:
1583 ub_state_done(sc, cmd, rc);
1584 }
1585
1586 /*
1587 * A helper for the command's state machine:
1588 * Submit a stall clear.
1589 */
1590 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
1591 int stalled_pipe)
1592 {
1593 int endp;
1594 struct usb_ctrlrequest *cr;
1595 int rc;
1596
1597 endp = usb_pipeendpoint(stalled_pipe);
1598 if (usb_pipein (stalled_pipe))
1599 endp |= USB_DIR_IN;
1600
1601 cr = &sc->work_cr;
1602 cr->bRequestType = USB_RECIP_ENDPOINT;
1603 cr->bRequest = USB_REQ_CLEAR_FEATURE;
1604 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
1605 cr->wIndex = cpu_to_le16(endp);
1606 cr->wLength = cpu_to_le16(0);
1607
1608 UB_INIT_COMPLETION(sc->work_done);
1609
1610 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
1611 (unsigned char*) cr, NULL, 0, ub_urb_complete, sc);
1612 sc->work_urb.transfer_flags = URB_ASYNC_UNLINK;
1613 sc->work_urb.actual_length = 0;
1614 sc->work_urb.error_count = 0;
1615 sc->work_urb.status = 0;
1616
1617 if ((rc = usb_submit_urb(&sc->work_urb, GFP_ATOMIC)) != 0) {
1618 ub_complete(&sc->work_done);
1619 return rc;
1620 }
1621
1622 sc->work_timer.expires = jiffies + UB_CTRL_TIMEOUT;
1623 add_timer(&sc->work_timer);
1624 return 0;
1625 }
1626
1627 /*
1628 */
1629 static void ub_top_sense_done(struct ub_dev *sc, struct ub_scsi_cmd *scmd)
1630 {
1631 unsigned char *sense = scmd->data;
1632 struct ub_scsi_cmd *cmd;
1633
1634 /*
1635 * Ignoring scmd->act_len, because the buffer was pre-zeroed.
1636 */
1637 ub_cmdtr_sense(sc, scmd, sense);
1638
1639 /*
1640 * Find the command which triggered the unit attention or a check,
1641 * save the sense into it, and advance its state machine.
1642 */
1643 if ((cmd = ub_cmdq_peek(sc)) == NULL) {
1644 printk(KERN_WARNING "%s: sense done while idle\n", sc->name);
1645 return;
1646 }
1647 if (cmd != scmd->back) {
1648 printk(KERN_WARNING "%s: "
1649 "sense done for wrong command 0x%x\n",
1650 sc->name, cmd->tag);
1651 return;
1652 }
1653 if (cmd->state != UB_CMDST_SENSE) {
1654 printk(KERN_WARNING "%s: "
1655 "sense done with bad cmd state %d\n",
1656 sc->name, cmd->state);
1657 return;
1658 }
1659
1660 cmd->key = sense[2] & 0x0F;
1661 cmd->asc = sense[12];
1662 cmd->ascq = sense[13];
1663
1664 ub_scsi_urb_compl(sc, cmd);
1665 }
1666
1667 /*
1668 * This is called from a process context.
1669 */
1670 static void ub_revalidate(struct ub_dev *sc, struct ub_lun *lun)
1671 {
1672
1673 lun->readonly = 0; /* XXX Query this from the device */
1674
1675 lun->capacity.nsec = 0;
1676 lun->capacity.bsize = 512;
1677 lun->capacity.bshift = 0;
1678
1679 if (ub_sync_tur(sc, lun) != 0)
1680 return; /* Not ready */
1681 lun->changed = 0;
1682
1683 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1684 /*
1685 * The retry here means something is wrong, either with the
1686 * device, with the transport, or with our code.
1687 * We keep this because sd.c has retries for capacity.
1688 */
1689 if (ub_sync_read_cap(sc, lun, &lun->capacity) != 0) {
1690 lun->capacity.nsec = 0;
1691 lun->capacity.bsize = 512;
1692 lun->capacity.bshift = 0;
1693 }
1694 }
1695 }
1696
1697 /*
1698 * The open funcion.
1699 * This is mostly needed to keep refcounting, but also to support
1700 * media checks on removable media drives.
1701 */
1702 static int ub_bd_open(struct inode *inode, struct file *filp)
1703 {
1704 struct gendisk *disk = inode->i_bdev->bd_disk;
1705 struct ub_lun *lun;
1706 struct ub_dev *sc;
1707 unsigned long flags;
1708 int rc;
1709
1710 if ((lun = disk->private_data) == NULL)
1711 return -ENXIO;
1712 sc = lun->udev;
1713
1714 spin_lock_irqsave(&ub_lock, flags);
1715 if (atomic_read(&sc->poison)) {
1716 spin_unlock_irqrestore(&ub_lock, flags);
1717 return -ENXIO;
1718 }
1719 sc->openc++;
1720 spin_unlock_irqrestore(&ub_lock, flags);
1721
1722 /*
1723 * This is a workaround for a specific problem in our block layer.
1724 * In 2.6.9, register_disk duplicates the code from rescan_partitions.
1725 * However, if we do add_disk with a device which persistently reports
1726 * a changed media, add_disk calls register_disk, which does do_open,
1727 * which will call rescan_paritions for changed media. After that,
1728 * register_disk attempts to do it all again and causes double kobject
1729 * registration and a eventually an oops on module removal.
1730 *
1731 * The bottom line is, Al Viro says that we should not allow
1732 * bdev->bd_invalidated to be set when doing add_disk no matter what.
1733 */
1734 if (lun->first_open) {
1735 lun->first_open = 0;
1736 if (lun->changed) {
1737 rc = -ENOMEDIUM;
1738 goto err_open;
1739 }
1740 }
1741
1742 if (lun->removable || lun->readonly)
1743 check_disk_change(inode->i_bdev);
1744
1745 /*
1746 * The sd.c considers ->media_present and ->changed not equivalent,
1747 * under some pretty murky conditions (a failure of READ CAPACITY).
1748 * We may need it one day.
1749 */
1750 if (lun->removable && lun->changed && !(filp->f_flags & O_NDELAY)) {
1751 rc = -ENOMEDIUM;
1752 goto err_open;
1753 }
1754
1755 if (lun->readonly && (filp->f_mode & FMODE_WRITE)) {
1756 rc = -EROFS;
1757 goto err_open;
1758 }
1759
1760 return 0;
1761
1762 err_open:
1763 ub_put(sc);
1764 return rc;
1765 }
1766
1767 /*
1768 */
1769 static int ub_bd_release(struct inode *inode, struct file *filp)
1770 {
1771 struct gendisk *disk = inode->i_bdev->bd_disk;
1772 struct ub_lun *lun = disk->private_data;
1773 struct ub_dev *sc = lun->udev;
1774
1775 ub_put(sc);
1776 return 0;
1777 }
1778
1779 /*
1780 * The ioctl interface.
1781 */
1782 static int ub_bd_ioctl(struct inode *inode, struct file *filp,
1783 unsigned int cmd, unsigned long arg)
1784 {
1785 struct gendisk *disk = inode->i_bdev->bd_disk;
1786 void __user *usermem = (void __user *) arg;
1787
1788 return scsi_cmd_ioctl(filp, disk, cmd, usermem);
1789 }
1790
1791 /*
1792 * This is called once a new disk was seen by the block layer or by ub_probe().
1793 * The main onjective here is to discover the features of the media such as
1794 * the capacity, read-only status, etc. USB storage generally does not
1795 * need to be spun up, but if we needed it, this would be the place.
1796 *
1797 * This call can sleep.
1798 *
1799 * The return code is not used.
1800 */
1801 static int ub_bd_revalidate(struct gendisk *disk)
1802 {
1803 struct ub_lun *lun = disk->private_data;
1804
1805 ub_revalidate(lun->udev, lun);
1806
1807 /* XXX Support sector size switching like in sr.c */
1808 blk_queue_hardsect_size(disk->queue, lun->capacity.bsize);
1809 set_capacity(disk, lun->capacity.nsec);
1810 // set_disk_ro(sdkp->disk, lun->readonly);
1811
1812 return 0;
1813 }
1814
1815 /*
1816 * The check is called by the block layer to verify if the media
1817 * is still available. It is supposed to be harmless, lightweight and
1818 * non-intrusive in case the media was not changed.
1819 *
1820 * This call can sleep.
1821 *
1822 * The return code is bool!
1823 */
1824 static int ub_bd_media_changed(struct gendisk *disk)
1825 {
1826 struct ub_lun *lun = disk->private_data;
1827
1828 if (!lun->removable)
1829 return 0;
1830
1831 /*
1832 * We clean checks always after every command, so this is not
1833 * as dangerous as it looks. If the TEST_UNIT_READY fails here,
1834 * the device is actually not ready with operator or software
1835 * intervention required. One dangerous item might be a drive which
1836 * spins itself down, and come the time to write dirty pages, this
1837 * will fail, then block layer discards the data. Since we never
1838 * spin drives up, such devices simply cannot be used with ub anyway.
1839 */
1840 if (ub_sync_tur(lun->udev, lun) != 0) {
1841 lun->changed = 1;
1842 return 1;
1843 }
1844
1845 return lun->changed;
1846 }
1847
1848 static struct block_device_operations ub_bd_fops = {
1849 .owner = THIS_MODULE,
1850 .open = ub_bd_open,
1851 .release = ub_bd_release,
1852 .ioctl = ub_bd_ioctl,
1853 .media_changed = ub_bd_media_changed,
1854 .revalidate_disk = ub_bd_revalidate,
1855 };
1856
1857 /*
1858 * Common ->done routine for commands executed synchronously.
1859 */
1860 static void ub_probe_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
1861 {
1862 struct completion *cop = cmd->back;
1863 complete(cop);
1864 }
1865
1866 /*
1867 * Test if the device has a check condition on it, synchronously.
1868 */
1869 static int ub_sync_tur(struct ub_dev *sc, struct ub_lun *lun)
1870 {
1871 struct ub_scsi_cmd *cmd;
1872 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) };
1873 unsigned long flags;
1874 struct completion compl;
1875 int rc;
1876
1877 init_completion(&compl);
1878
1879 rc = -ENOMEM;
1880 if ((cmd = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1881 goto err_alloc;
1882 memset(cmd, 0, ALLOC_SIZE);
1883
1884 cmd->cdb[0] = TEST_UNIT_READY;
1885 cmd->cdb_len = 6;
1886 cmd->dir = UB_DIR_NONE;
1887 cmd->state = UB_CMDST_INIT;
1888 cmd->lun = lun; /* This may be NULL, but that's ok */
1889 cmd->done = ub_probe_done;
1890 cmd->back = &compl;
1891
1892 spin_lock_irqsave(&sc->lock, flags);
1893 cmd->tag = sc->tagcnt++;
1894
1895 rc = ub_submit_scsi(sc, cmd);
1896 spin_unlock_irqrestore(&sc->lock, flags);
1897
1898 if (rc != 0) {
1899 printk("ub: testing ready: submit error (%d)\n", rc); /* P3 */
1900 goto err_submit;
1901 }
1902
1903 wait_for_completion(&compl);
1904
1905 rc = cmd->error;
1906
1907 if (rc == -EIO && cmd->key != 0) /* Retries for benh's key */
1908 rc = cmd->key;
1909
1910 err_submit:
1911 kfree(cmd);
1912 err_alloc:
1913 return rc;
1914 }
1915
1916 /*
1917 * Read the SCSI capacity synchronously (for probing).
1918 */
1919 static int ub_sync_read_cap(struct ub_dev *sc, struct ub_lun *lun,
1920 struct ub_capacity *ret)
1921 {
1922 struct ub_scsi_cmd *cmd;
1923 char *p;
1924 enum { ALLOC_SIZE = sizeof(struct ub_scsi_cmd) + 8 };
1925 unsigned long flags;
1926 unsigned int bsize, shift;
1927 unsigned long nsec;
1928 struct completion compl;
1929 int rc;
1930
1931 init_completion(&compl);
1932
1933 rc = -ENOMEM;
1934 if ((cmd = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
1935 goto err_alloc;
1936 memset(cmd, 0, ALLOC_SIZE);
1937 p = (char *)cmd + sizeof(struct ub_scsi_cmd);
1938
1939 cmd->cdb[0] = 0x25;
1940 cmd->cdb_len = 10;
1941 cmd->dir = UB_DIR_READ;
1942 cmd->state = UB_CMDST_INIT;
1943 cmd->data = p;
1944 cmd->len = 8;
1945 cmd->lun = lun;
1946 cmd->done = ub_probe_done;
1947 cmd->back = &compl;
1948
1949 spin_lock_irqsave(&sc->lock, flags);
1950 cmd->tag = sc->tagcnt++;
1951
1952 rc = ub_submit_scsi(sc, cmd);
1953 spin_unlock_irqrestore(&sc->lock, flags);
1954
1955 if (rc != 0) {
1956 printk("ub: reading capacity: submit error (%d)\n", rc); /* P3 */
1957 goto err_submit;
1958 }
1959
1960 wait_for_completion(&compl);
1961
1962 if (cmd->error != 0) {
1963 printk("ub: reading capacity: error %d\n", cmd->error); /* P3 */
1964 rc = -EIO;
1965 goto err_read;
1966 }
1967 if (cmd->act_len != 8) {
1968 printk("ub: reading capacity: size %d\n", cmd->act_len); /* P3 */
1969 rc = -EIO;
1970 goto err_read;
1971 }
1972
1973 /* sd.c special-cases sector size of 0 to mean 512. Needed? Safe? */
1974 nsec = be32_to_cpu(*(__be32 *)p) + 1;
1975 bsize = be32_to_cpu(*(__be32 *)(p + 4));
1976 switch (bsize) {
1977 case 512: shift = 0; break;
1978 case 1024: shift = 1; break;
1979 case 2048: shift = 2; break;
1980 case 4096: shift = 3; break;
1981 default:
1982 printk("ub: Bad sector size %u\n", bsize); /* P3 */
1983 rc = -EDOM;
1984 goto err_inv_bsize;
1985 }
1986
1987 ret->bsize = bsize;
1988 ret->bshift = shift;
1989 ret->nsec = nsec << shift;
1990 rc = 0;
1991
1992 err_inv_bsize:
1993 err_read:
1994 err_submit:
1995 kfree(cmd);
1996 err_alloc:
1997 return rc;
1998 }
1999
2000 /*
2001 */
2002 static void ub_probe_urb_complete(struct urb *urb, struct pt_regs *pt)
2003 {
2004 struct completion *cop = urb->context;
2005 complete(cop);
2006 }
2007
2008 static void ub_probe_timeout(unsigned long arg)
2009 {
2010 struct completion *cop = (struct completion *) arg;
2011 complete(cop);
2012 }
2013
2014 /*
2015 * Get number of LUNs by the way of Bulk GetMaxLUN command.
2016 */
2017 static int ub_sync_getmaxlun(struct ub_dev *sc)
2018 {
2019 int ifnum = sc->intf->cur_altsetting->desc.bInterfaceNumber;
2020 unsigned char *p;
2021 enum { ALLOC_SIZE = 1 };
2022 struct usb_ctrlrequest *cr;
2023 struct completion compl;
2024 struct timer_list timer;
2025 int nluns;
2026 int rc;
2027
2028 init_completion(&compl);
2029
2030 rc = -ENOMEM;
2031 if ((p = kmalloc(ALLOC_SIZE, GFP_KERNEL)) == NULL)
2032 goto err_alloc;
2033 *p = 55;
2034
2035 cr = &sc->work_cr;
2036 cr->bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE;
2037 cr->bRequest = US_BULK_GET_MAX_LUN;
2038 cr->wValue = cpu_to_le16(0);
2039 cr->wIndex = cpu_to_le16(ifnum);
2040 cr->wLength = cpu_to_le16(1);
2041
2042 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->recv_ctrl_pipe,
2043 (unsigned char*) cr, p, 1, ub_probe_urb_complete, &compl);
2044 sc->work_urb.transfer_flags = 0;
2045 sc->work_urb.actual_length = 0;
2046 sc->work_urb.error_count = 0;
2047 sc->work_urb.status = 0;
2048
2049 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
2050 if (rc == -EPIPE) {
2051 printk("%s: Stall at GetMaxLUN, using 1 LUN\n",
2052 sc->name); /* P3 */
2053 } else {
2054 printk(KERN_WARNING
2055 "%s: Unable to submit GetMaxLUN (%d)\n",
2056 sc->name, rc);
2057 }
2058 goto err_submit;
2059 }
2060
2061 init_timer(&timer);
2062 timer.function = ub_probe_timeout;
2063 timer.data = (unsigned long) &compl;
2064 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2065 add_timer(&timer);
2066
2067 wait_for_completion(&compl);
2068
2069 del_timer_sync(&timer);
2070 usb_kill_urb(&sc->work_urb);
2071
2072 if (sc->work_urb.actual_length != 1) {
2073 printk("%s: GetMaxLUN returned %d bytes\n", sc->name,
2074 sc->work_urb.actual_length); /* P3 */
2075 nluns = 0;
2076 } else {
2077 if ((nluns = *p) == 55) {
2078 nluns = 0;
2079 } else {
2080 /* GetMaxLUN returns the maximum LUN number */
2081 nluns += 1;
2082 if (nluns > UB_MAX_LUNS)
2083 nluns = UB_MAX_LUNS;
2084 }
2085 printk("%s: GetMaxLUN returned %d, using %d LUNs\n", sc->name,
2086 *p, nluns); /* P3 */
2087 }
2088
2089 kfree(p);
2090 return nluns;
2091
2092 err_submit:
2093 kfree(p);
2094 err_alloc:
2095 return rc;
2096 }
2097
2098 /*
2099 * Clear initial stalls.
2100 */
2101 static int ub_probe_clear_stall(struct ub_dev *sc, int stalled_pipe)
2102 {
2103 int endp;
2104 struct usb_ctrlrequest *cr;
2105 struct completion compl;
2106 struct timer_list timer;
2107 int rc;
2108
2109 init_completion(&compl);
2110
2111 endp = usb_pipeendpoint(stalled_pipe);
2112 if (usb_pipein (stalled_pipe))
2113 endp |= USB_DIR_IN;
2114
2115 cr = &sc->work_cr;
2116 cr->bRequestType = USB_RECIP_ENDPOINT;
2117 cr->bRequest = USB_REQ_CLEAR_FEATURE;
2118 cr->wValue = cpu_to_le16(USB_ENDPOINT_HALT);
2119 cr->wIndex = cpu_to_le16(endp);
2120 cr->wLength = cpu_to_le16(0);
2121
2122 usb_fill_control_urb(&sc->work_urb, sc->dev, sc->send_ctrl_pipe,
2123 (unsigned char*) cr, NULL, 0, ub_probe_urb_complete, &compl);
2124 sc->work_urb.transfer_flags = 0;
2125 sc->work_urb.actual_length = 0;
2126 sc->work_urb.error_count = 0;
2127 sc->work_urb.status = 0;
2128
2129 if ((rc = usb_submit_urb(&sc->work_urb, GFP_KERNEL)) != 0) {
2130 printk(KERN_WARNING
2131 "%s: Unable to submit a probe clear (%d)\n", sc->name, rc);
2132 return rc;
2133 }
2134
2135 init_timer(&timer);
2136 timer.function = ub_probe_timeout;
2137 timer.data = (unsigned long) &compl;
2138 timer.expires = jiffies + UB_CTRL_TIMEOUT;
2139 add_timer(&timer);
2140
2141 wait_for_completion(&compl);
2142
2143 del_timer_sync(&timer);
2144 usb_kill_urb(&sc->work_urb);
2145
2146 /* reset the endpoint toggle */
2147 usb_settoggle(sc->dev, endp, usb_pipeout(sc->last_pipe), 0);
2148
2149 return 0;
2150 }
2151
2152 /*
2153 * Get the pipe settings.
2154 */
2155 static int ub_get_pipes(struct ub_dev *sc, struct usb_device *dev,
2156 struct usb_interface *intf)
2157 {
2158 struct usb_host_interface *altsetting = intf->cur_altsetting;
2159 struct usb_endpoint_descriptor *ep_in = NULL;
2160 struct usb_endpoint_descriptor *ep_out = NULL;
2161 struct usb_endpoint_descriptor *ep;
2162 int i;
2163
2164 /*
2165 * Find the endpoints we need.
2166 * We are expecting a minimum of 2 endpoints - in and out (bulk).
2167 * We will ignore any others.
2168 */
2169 for (i = 0; i < altsetting->desc.bNumEndpoints; i++) {
2170 ep = &altsetting->endpoint[i].desc;
2171
2172 /* Is it a BULK endpoint? */
2173 if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
2174 == USB_ENDPOINT_XFER_BULK) {
2175 /* BULK in or out? */
2176 if (ep->bEndpointAddress & USB_DIR_IN)
2177 ep_in = ep;
2178 else
2179 ep_out = ep;
2180 }
2181 }
2182
2183 if (ep_in == NULL || ep_out == NULL) {
2184 printk(KERN_NOTICE "%s: failed endpoint check\n",
2185 sc->name);
2186 return -EIO;
2187 }
2188
2189 /* Calculate and store the pipe values */
2190 sc->send_ctrl_pipe = usb_sndctrlpipe(dev, 0);
2191 sc->recv_ctrl_pipe = usb_rcvctrlpipe(dev, 0);
2192 sc->send_bulk_pipe = usb_sndbulkpipe(dev,
2193 ep_out->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2194 sc->recv_bulk_pipe = usb_rcvbulkpipe(dev,
2195 ep_in->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2196
2197 return 0;
2198 }
2199
2200 /*
2201 * Probing is done in the process context, which allows us to cheat
2202 * and not to build a state machine for the discovery.
2203 */
2204 static int ub_probe(struct usb_interface *intf,
2205 const struct usb_device_id *dev_id)
2206 {
2207 struct ub_dev *sc;
2208 int nluns;
2209 int rc;
2210 int i;
2211
2212 rc = -ENOMEM;
2213 if ((sc = kmalloc(sizeof(struct ub_dev), GFP_KERNEL)) == NULL)
2214 goto err_core;
2215 memset(sc, 0, sizeof(struct ub_dev));
2216 spin_lock_init(&sc->lock);
2217 INIT_LIST_HEAD(&sc->luns);
2218 usb_init_urb(&sc->work_urb);
2219 tasklet_init(&sc->tasklet, ub_scsi_action, (unsigned long)sc);
2220 atomic_set(&sc->poison, 0);
2221
2222 init_timer(&sc->work_timer);
2223 sc->work_timer.data = (unsigned long) sc;
2224 sc->work_timer.function = ub_urb_timeout;
2225
2226 ub_init_completion(&sc->work_done);
2227 sc->work_done.done = 1; /* A little yuk, but oh well... */
2228
2229 sc->dev = interface_to_usbdev(intf);
2230 sc->intf = intf;
2231 // sc->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2232 usb_set_intfdata(intf, sc);
2233 usb_get_dev(sc->dev);
2234 // usb_get_intf(sc->intf); /* Do we need this? */
2235
2236 snprintf(sc->name, 12, DRV_NAME "(%d.%d)",
2237 sc->dev->bus->busnum, sc->dev->devnum);
2238
2239 /* XXX Verify that we can handle the device (from descriptors) */
2240
2241 ub_get_pipes(sc, sc->dev, intf);
2242
2243 if (device_create_file(&sc->intf->dev, &dev_attr_diag) != 0)
2244 goto err_diag;
2245
2246 /*
2247 * At this point, all USB initialization is done, do upper layer.
2248 * We really hate halfway initialized structures, so from the
2249 * invariants perspective, this ub_dev is fully constructed at
2250 * this point.
2251 */
2252
2253 /*
2254 * This is needed to clear toggles. It is a problem only if we do
2255 * `rmmod ub && modprobe ub` without disconnects, but we like that.
2256 */
2257 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
2258 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
2259
2260 /*
2261 * The way this is used by the startup code is a little specific.
2262 * A SCSI check causes a USB stall. Our common case code sees it
2263 * and clears the check, after which the device is ready for use.
2264 * But if a check was not present, any command other than
2265 * TEST_UNIT_READY ends with a lockup (including REQUEST_SENSE).
2266 *
2267 * If we neglect to clear the SCSI check, the first real command fails
2268 * (which is the capacity readout). We clear that and retry, but why
2269 * causing spurious retries for no reason.
2270 *
2271 * Revalidation may start with its own TEST_UNIT_READY, but that one
2272 * has to succeed, so we clear checks with an additional one here.
2273 * In any case it's not our business how revaliadation is implemented.
2274 */
2275 for (i = 0; i < 3; i++) { /* Retries for benh's key */
2276 if ((rc = ub_sync_tur(sc, NULL)) <= 0) break;
2277 if (rc != 0x6) break;
2278 msleep(10);
2279 }
2280
2281 nluns = 1;
2282 for (i = 0; i < 3; i++) {
2283 if ((rc = ub_sync_getmaxlun(sc)) < 0) {
2284 /*
2285 * Some devices (i.e. Iomega Zip100) need this --
2286 * apparently the bulk pipes get STALLed when the
2287 * GetMaxLUN request is processed.
2288 * XXX I have a ZIP-100, verify it does this.
2289 */
2290 if (rc == -EPIPE) {
2291 ub_probe_clear_stall(sc, sc->recv_bulk_pipe);
2292 ub_probe_clear_stall(sc, sc->send_bulk_pipe);
2293 }
2294 break;
2295 }
2296 if (rc != 0) {
2297 nluns = rc;
2298 break;
2299 }
2300 msleep(100);
2301 }
2302
2303 for (i = 0; i < nluns; i++) {
2304 ub_probe_lun(sc, i);
2305 }
2306 return 0;
2307
2308 /* device_remove_file(&sc->intf->dev, &dev_attr_diag); */
2309 err_diag:
2310 usb_set_intfdata(intf, NULL);
2311 // usb_put_intf(sc->intf);
2312 usb_put_dev(sc->dev);
2313 kfree(sc);
2314 err_core:
2315 return rc;
2316 }
2317
2318 static int ub_probe_lun(struct ub_dev *sc, int lnum)
2319 {
2320 struct ub_lun *lun;
2321 request_queue_t *q;
2322 struct gendisk *disk;
2323 int rc;
2324
2325 rc = -ENOMEM;
2326 if ((lun = kmalloc(sizeof(struct ub_lun), GFP_KERNEL)) == NULL)
2327 goto err_alloc;
2328 memset(lun, 0, sizeof(struct ub_lun));
2329 lun->num = lnum;
2330
2331 rc = -ENOSR;
2332 if ((lun->id = ub_id_get()) == -1)
2333 goto err_id;
2334
2335 lun->udev = sc;
2336 list_add(&lun->link, &sc->luns);
2337
2338 snprintf(lun->name, 16, DRV_NAME "%c(%d.%d.%d)",
2339 lun->id + 'a', sc->dev->bus->busnum, sc->dev->devnum, lun->num);
2340
2341 lun->removable = 1; /* XXX Query this from the device */
2342 lun->changed = 1; /* ub_revalidate clears only */
2343 lun->first_open = 1;
2344 ub_revalidate(sc, lun);
2345
2346 rc = -ENOMEM;
2347 if ((disk = alloc_disk(UB_MINORS_PER_MAJOR)) == NULL)
2348 goto err_diskalloc;
2349
2350 lun->disk = disk;
2351 sprintf(disk->disk_name, DRV_NAME "%c", lun->id + 'a');
2352 sprintf(disk->devfs_name, DEVFS_NAME "/%c", lun->id + 'a');
2353 disk->major = UB_MAJOR;
2354 disk->first_minor = lun->id * UB_MINORS_PER_MAJOR;
2355 disk->fops = &ub_bd_fops;
2356 disk->private_data = lun;
2357 disk->driverfs_dev = &sc->intf->dev; /* XXX Many to one ok? */
2358
2359 rc = -ENOMEM;
2360 if ((q = blk_init_queue(ub_request_fn, &sc->lock)) == NULL)
2361 goto err_blkqinit;
2362
2363 disk->queue = q;
2364
2365 blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
2366 blk_queue_max_hw_segments(q, UB_MAX_REQ_SG);
2367 blk_queue_max_phys_segments(q, UB_MAX_REQ_SG);
2368 blk_queue_segment_boundary(q, 0xffffffff); /* Dubious. */
2369 blk_queue_max_sectors(q, UB_MAX_SECTORS);
2370 blk_queue_hardsect_size(q, lun->capacity.bsize);
2371
2372 q->queuedata = lun;
2373
2374 set_capacity(disk, lun->capacity.nsec);
2375 if (lun->removable)
2376 disk->flags |= GENHD_FL_REMOVABLE;
2377
2378 add_disk(disk);
2379
2380 return 0;
2381
2382 err_blkqinit:
2383 put_disk(disk);
2384 err_diskalloc:
2385 list_del(&lun->link);
2386 ub_id_put(lun->id);
2387 err_id:
2388 kfree(lun);
2389 err_alloc:
2390 return rc;
2391 }
2392
2393 static void ub_disconnect(struct usb_interface *intf)
2394 {
2395 struct ub_dev *sc = usb_get_intfdata(intf);
2396 struct list_head *p;
2397 struct ub_lun *lun;
2398 struct gendisk *disk;
2399 unsigned long flags;
2400
2401 /*
2402 * Prevent ub_bd_release from pulling the rug from under us.
2403 * XXX This is starting to look like a kref.
2404 * XXX Why not to take this ref at probe time?
2405 */
2406 spin_lock_irqsave(&ub_lock, flags);
2407 sc->openc++;
2408 spin_unlock_irqrestore(&ub_lock, flags);
2409
2410 /*
2411 * Fence stall clearnings, operations triggered by unlinkings and so on.
2412 * We do not attempt to unlink any URBs, because we do not trust the
2413 * unlink paths in HC drivers. Also, we get -84 upon disconnect anyway.
2414 */
2415 atomic_set(&sc->poison, 1);
2416
2417 /*
2418 * Blow away queued commands.
2419 *
2420 * Actually, this never works, because before we get here
2421 * the HCD terminates outstanding URB(s). It causes our
2422 * SCSI command queue to advance, commands fail to submit,
2423 * and the whole queue drains. So, we just use this code to
2424 * print warnings.
2425 */
2426 spin_lock_irqsave(&sc->lock, flags);
2427 {
2428 struct ub_scsi_cmd *cmd;
2429 int cnt = 0;
2430 while ((cmd = ub_cmdq_pop(sc)) != NULL) {
2431 cmd->error = -ENOTCONN;
2432 cmd->state = UB_CMDST_DONE;
2433 ub_cmdtr_state(sc, cmd);
2434 ub_cmdq_pop(sc);
2435 (*cmd->done)(sc, cmd);
2436 cnt++;
2437 }
2438 if (cnt != 0) {
2439 printk(KERN_WARNING "%s: "
2440 "%d was queued after shutdown\n", sc->name, cnt);
2441 }
2442 }
2443 spin_unlock_irqrestore(&sc->lock, flags);
2444
2445 /*
2446 * Unregister the upper layer.
2447 */
2448 list_for_each (p, &sc->luns) {
2449 lun = list_entry(p, struct ub_lun, link);
2450 disk = lun->disk;
2451 if (disk->flags & GENHD_FL_UP)
2452 del_gendisk(disk);
2453 /*
2454 * I wish I could do:
2455 * set_bit(QUEUE_FLAG_DEAD, &q->queue_flags);
2456 * As it is, we rely on our internal poisoning and let
2457 * the upper levels to spin furiously failing all the I/O.
2458 */
2459 }
2460
2461 /*
2462 * Taking a lock on a structure which is about to be freed
2463 * is very nonsensual. Here it is largely a way to do a debug freeze,
2464 * and a bracket which shows where the nonsensual code segment ends.
2465 *
2466 * Testing for -EINPROGRESS is always a bug, so we are bending
2467 * the rules a little.
2468 */
2469 spin_lock_irqsave(&sc->lock, flags);
2470 if (sc->work_urb.status == -EINPROGRESS) { /* janitors: ignore */
2471 printk(KERN_WARNING "%s: "
2472 "URB is active after disconnect\n", sc->name);
2473 }
2474 spin_unlock_irqrestore(&sc->lock, flags);
2475
2476 /*
2477 * There is virtually no chance that other CPU runs times so long
2478 * after ub_urb_complete should have called del_timer, but only if HCD
2479 * didn't forget to deliver a callback on unlink.
2480 */
2481 del_timer_sync(&sc->work_timer);
2482
2483 /*
2484 * At this point there must be no commands coming from anyone
2485 * and no URBs left in transit.
2486 */
2487
2488 device_remove_file(&sc->intf->dev, &dev_attr_diag);
2489 usb_set_intfdata(intf, NULL);
2490 // usb_put_intf(sc->intf);
2491 sc->intf = NULL;
2492 usb_put_dev(sc->dev);
2493 sc->dev = NULL;
2494
2495 ub_put(sc);
2496 }
2497
2498 static struct usb_driver ub_driver = {
2499 .owner = THIS_MODULE,
2500 .name = "ub",
2501 .probe = ub_probe,
2502 .disconnect = ub_disconnect,
2503 .id_table = ub_usb_ids,
2504 };
2505
2506 static int __init ub_init(void)
2507 {
2508 int rc;
2509
2510 /* P3 */ printk("ub: sizeof ub_scsi_cmd %zu ub_dev %zu ub_lun %zu\n",
2511 sizeof(struct ub_scsi_cmd), sizeof(struct ub_dev), sizeof(struct ub_lun));
2512
2513 if ((rc = register_blkdev(UB_MAJOR, DRV_NAME)) != 0)
2514 goto err_regblkdev;
2515 devfs_mk_dir(DEVFS_NAME);
2516
2517 if ((rc = usb_register(&ub_driver)) != 0)
2518 goto err_register;
2519
2520 return 0;
2521
2522 err_register:
2523 devfs_remove(DEVFS_NAME);
2524 unregister_blkdev(UB_MAJOR, DRV_NAME);
2525 err_regblkdev:
2526 return rc;
2527 }
2528
2529 static void __exit ub_exit(void)
2530 {
2531 usb_deregister(&ub_driver);
2532
2533 devfs_remove(DEVFS_NAME);
2534 unregister_blkdev(UB_MAJOR, DRV_NAME);
2535 }
2536
2537 module_init(ub_init);
2538 module_exit(ub_exit);
2539
2540 MODULE_LICENSE("GPL");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree